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Sample records for metabolism cell survival

  1. Oral cancer cells may rewire alternative metabolic pathways to survive from siRNA silencing of metabolic enzymes

    Zhang, Min; Chai, Yang D; Brumbaugh, Jeffrey; Liu, Xiaojun; Rabii, Ramin; Feng, Sizhe; Misuno, Kaori; Messadi, Diana; Hu, Shen

    2014-01-01

    Cancer cells may undergo metabolic adaptations that support their growth as well as drug resistance properties. The purpose of this study is to test if oral cancer cells can overcome the metabolic defects introduced by using small interfering RNA (siRNA) to knock down their expression of important metabolic enzymes. UM1 and UM2 oral cancer cells were transfected with siRNA to transketolase (TKT) or siRNA to adenylate kinase (AK2), and Western blotting was used to confirm the knockdown. Cellular uptake of glucose and glutamine and production of lactate were compared between the cancer cells with either TKT or AK2 knockdown and those transfected with control siRNA. Statistical analysis was performed with student T-test. Despite the defect in the pentose phosphate pathway caused by siRNA knockdown of TKT, the survived UM1 or UM2 cells utilized more glucose and glutamine and secreted a significantly higher amount of lactate than the cells transferred with control siRNA. We also demonstrated that siRNA knockdown of AK2 constrained the proliferation of UM1 and UM2 cells but similarly led to an increased uptake of glucose/glutamine and production of lactate by the UM1 or UM2 cells survived from siRNA silencing of AK2. Our results indicate that the metabolic defects introduced by siRNA silencing of metabolic enzymes TKT or AK2 may be compensated by alternative feedback metabolic mechanisms, suggesting that cancer cells may overcome single defective pathways through secondary metabolic network adaptations. The highly robust nature of oral cancer cell metabolism implies that a systematic medical approach targeting multiple metabolic pathways may be needed to accomplish the continued improvement of cancer treatment

  2. Metabolic profiling of hypoxic cells revealed a catabolic signature required for cell survival.

    Christian Frezza

    Full Text Available Hypoxia is one of the features of poorly vascularised areas of solid tumours but cancer cells can survive in these areas despite the low oxygen tension. The adaptation to hypoxia requires both biochemical and genetic responses that culminate in a metabolic rearrangement to counter-balance the decrease in energy supply from mitochondrial respiration. The understanding of metabolic adaptations under hypoxia could reveal novel pathways that, if targeted, would lead to specific death of hypoxic regions. In this study, we developed biochemical and metabolomic analyses to assess the effects of hypoxia on cellular metabolism of HCT116 cancer cell line. We utilized an oxygen fluorescent probe in anaerobic cuvettes to study oxygen consumption rates under hypoxic conditions without the need to re-oxygenate the cells and demonstrated that hypoxic cells can maintain active, though diminished, oxidative phosphorylation even at 1% oxygen. These results were further supported by in situ microscopy analysis of mitochondrial NADH oxidation under hypoxia. We then used metabolomic methodologies, utilizing liquid chromatography-mass spectrometry (LC-MS, to determine the metabolic profile of hypoxic cells. This approach revealed the importance of synchronized and regulated catabolism as a mechanism of adaptation to bioenergetic stress. We then confirmed the presence of autophagy under hypoxic conditions and demonstrated that the inhibition of this catabolic process dramatically reduced the ATP levels in hypoxic cells and stimulated hypoxia-induced cell death. These results suggest that under hypoxia, autophagy is required to support ATP production, in addition to glycolysis, and that the inhibition of autophagy might be used to selectively target hypoxic regions of tumours, the most notoriously resistant areas of solid tumours.

  3. Mechanisms of redox metabolism and cancer cell survival during extracellular matrix detachment.

    Hawk, Mark A; Schafer, Zachary T

    2018-01-16

    Non-transformed cells that become detached from the extracellular matrix (ECM) undergo dysregulation of redox homeostasis and cell death. In contrast, cancer cells often acquire the ability to mitigate programmed cell death pathways and recalibrate the redox balance to survive after ECM detachment, facilitating metastatic dissemination. Accordingly, recent studies of the mechanisms by which cancer cells overcome ECM detachment-induced metabolic alterations have focused on mechanisms in redox homeostasis. The insights into these mechanisms may inform the development of therapeutics that manipulate redox homeostasis to eliminate ECM-detached cancer cells. Here, we review how ECM-detached cancer cells balance redox metabolism for survival. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Rewiring carbohydrate catabolism differentially affects survival of pancreatic cancer cell lines with diverse metabolic profiles

    Tataranni, Tiziana; Agriesti, Francesca; Ruggieri, Vitalba; Mazzoccoli, Carmela; Simeon, Vittorio; Laurenzana, Ilaria; Scrima, Rosella; Pazienza, Valerio; Capitanio, Nazzareno; Piccoli, Claudia

    2017-01-01

    An increasing body of evidence suggests that targeting cellular metabolism represents a promising effective approach to treat pancreatic cancer, overcome chemoresistance and ameliorate patient's prognosis and survival. In this study, following whole-genome expression analysis, we selected two pancreatic cancer cell lines, PANC-1 and BXPC-3, hallmarked by distinct metabolic profiles with specific concern to carbohydrate metabolism. Functional comparative analysis showed that BXPC-3 displayed a marked deficit of the mitochondrial respiratory and oxidative phosphorylation activity and a higher production of reactive oxygen species and a reduced NAD+/NADH ratio, indicating their bioenergetic reliance on glycolysis and a different redox homeostasis as compared to PANC-1. Both cell lines were challenged to rewire their metabolism by substituting glucose with galactose as carbon source, a condition inhibiting the glycolytic flux and fostering full oxidation of the sugar carbons. The obtained data strikingly show that the mitochondrial respiration-impaired-BXPC-3 cell line was unable to sustain the metabolic adaptation required by glucose deprivation/substitution, thereby resulting in a G2\\M cell cycle shift, unbalance of the redox homeostasis, apoptosis induction. Conversely, the mitochondrial respiration-competent-PANC-1 cell line did not show clear evidence of cell sufferance. Our findings provide a strong rationale to candidate metabolism as a promising target for cancer therapy. Defining the metabolic features at time of pancreatic cancer diagnosis and likely of other tumors, appears to be crucial to predict the responsiveness to therapeutic approaches or coadjuvant interventions affecting metabolism. PMID:28476035

  5. Effects of nicotinamide N-methyltransferase on PANC-1 cells proliferation, metastatic potential and survival under metabolic stress.

    Yu, Tao; Wang, Yong-Tao; Chen, Pan; Li, Yu-Hua; Chen, Yi-Xin; Zeng, Hang; Yu, Ai-Ming; Huang, Min; Bi, Hui-Chang

    2015-01-01

    Aberrant expression of Nicotinamide N-methyltransferase (NNMT) has been reported in pancreatic cancer. However, the role of NNMT in pancreatic cancer development remains elusive. Therefore, the present study was to investigate the impact of NNMT on pancreatic cancer cell proliferation, metastatic potential and survival under metabolic stress. Pancreatic cancer cell line PANC-1 was transfected with NNMT expression plasmid or small interfering RNA of NNMT to overexpress or knockdown intracellular NNMT expression, respectively. Rate of cell proliferation was monitored. Transwell migration and matrigel invasion assays were conducted to assess cell migration and invasion capacity. Resistance to glucose deprivation, sensitivity to glycolytic inhibition, mitochondrial inhibtion and resistance to rapamycin were examined to evaluate cell survival under metabolic stress. NNMT silencing markedly reduced cell proliferation, whereas NNMT overexpression promoted cell growth moderately. Knocking down NNMT also significantly suppressed the migration and invasion capacities of PANC-1 cells. Conversely, NNMT upregulation enhanced cell migration and invasion capacities. In addition, NNMT knockdown cells were much less resistant to glucose deprivation and rapamycin as well as glycolytic inhibitor 2-deoxyglucose whereas NNMT-expressing cells showed opposite effects although the effects were not so striking. These data sugguest that NNMT plays an important role in PANC-1 cell proliferation, metastatic potential and survival under metabolic stress. © 2015 S. Karger AG, Basel.

  6. Effects of Nicotinamide N-Methyltransferase on PANC-1 Cells Proliferation, Metastatic Potential and Survival Under Metabolic Stress

    Tao Yu

    2015-01-01

    Full Text Available Background: Aberrant expression of Nicotinamide N-methyltransferase (NNMT has been reported in pancreatic cancer. However, the role of NNMT in pancreatic cancer development remains elusive. Therefore, the present study was to investigate the impact of NNMT on pancreatic cancer cell proliferation, metastatic potential and survival under metabolic stress. Methods: Pancreatic cancer cell line PANC-1 was transfected with NNMT expression plasmid or small interfering RNA of NNMT to overexpress or knockdown intracellular NNMT expression, respectively. Rate of cell proliferation was monitored. Transwell migration and matrigel invasion assays were conducted to assess cell migration and invasion capacity. Resistance to glucose deprivation, sensitivity to glycolytic inhibition, mitochondrial inhibtion and resistance to rapamycin were examined to evaluate cell survival under metabolic stress. Results: NNMT silencing markedly reduced cell proliferation, whereas NNMT overexpression promoted cell growth moderately. Knocking down NNMT also significantly suppressed the migration and invasion capacities of PANC-1 cells. Conversely, NNMT upregulation enhanced cell migration and invasion capacities. In addition, NNMT knockdown cells were much less resistant to glucose deprivation and rapamycin as well as glycolytic inhibitor 2-deoxyglucose whereas NNMT-expressing cells showed opposite effects although the effects were not so striking. Conclusions: These data sugguest that NNMT plays an important role in PANC-1 cell proliferation, metastatic potential and survival under metabolic stress.

  7. Impact of plant extracts tested in attention-deficit/hyperactivity disorder treatment on cell survival and energy metabolism in human neuroblastoma SH-SY5Y cells.

    Schmidt, Andreas Johannes; Krieg, Jürgen-Christian; Hemmeter, Ulrich Michael; Kircher, Tilo; Schulz, Eberhard; Clement, Hans-Willi; Heiser, Philip

    2010-10-01

    Plant extracts such as Hypericum perforatum and Pycnogenol have been tested as alternatives to the classical ADHD drugs. It has been possible to describe neuroprotective effects of such plant extracts. A reduction of ADHD symptoms could be shown in clinical studies after the application of Pycnogenol, which is a pine bark extract. The impacts of the standardized herbal extracts Hypericum perforatum, Pycnogenol and Enzogenol up to a concentration of 5000 ng/mL on cell survival and energy metabolism in human SH-SY5Y neuroblastoma cells has been investigated in the present examination. Hypericum perforatum significantly decreased the survival of cells after treatment with a concentration of 5000 ng/mL, whereas lower concentrations exerted no significant effects. Pycnogenol( induced a significant increase of cell survival after incubation with a concentration of 32.25 ng/mL and a concentration of 250 ng/mL. Other applied concentrations of Pycnogenol failed to exert significant effects. Treatment with Enzogenol did not lead to significant changes in cell survival.Concerning energy metabolism, the treatment of cells with a concentration of 5000 ng/mL Hypericum perforatum led to a significant increase of ATP levels, whereas treatment with a concentration of 500 ng/mL had no significant effect. Incubation of cells with Pycnogenol and Enzogenol exerted no significant effects.None of the tested substances caused any cytotoxic effect when used in therapeutically relevant concentrations. Copyright © 2010 John Wiley & Sons, Ltd.

  8. The Impact of Drug Metabolism Gene Polymorphisms on Therapeutic Response and Survival in Diffuse Large B-Cell Lymphoma Patients.

    Pál, Ildikó; Illés, Árpád; Gergely, Lajos; Pál, Tibor; Radnay, Zita; Szekanecz, Zoltán; Zilahi, Erika; Váróczy, László

    2018-04-01

    Diffuse large B-cell lymphoma (DLBCL) accounts for 30% of all non-Hodgkin lymphomas (NHL) and 80% of agressive lymphomas. Besides the traditional International Prognostic Index (IPI), some other factors may also influence the prognosis of DLBCL patients. To study how the genetic polymorphisms in the metabolic pathway influence the event-free and overall survivals and therapeutic responses in DLBCL. The study was comprised of 51 patients (32 men, 19 women). The average age was 53.1 years. DLBCL was diagnosed between 2011 and 2016 and the average follow-up time was 3.78 years. These patients received 1-8 cycles (an average of 6.2 cycles) of rituximab, cyclophosphamide, doxorubicin, vincristin, prednisolon (R-CHOP) immunochemotherapy. Real-time polymerase chain reaction was used to determine the genetic polymorphisms of CYP2E1, GSTP1, NAT1, and NAT2 genes. Our results showed that the polymorphisms of CYP2E1, GSTP1, and NAT1 genes did not influence the prognosis of DLBCL patients significantly. In terms of the NAT2 gene, GG homozygous patients showed slightly better therapeutic response and survival results compared to those bearing an A allele; however, the differences were not statistically significant. Our results could not confirm that genetic polymorphism in metabolic pathways has any predictive role in DLBCL.

  9. Yeast Colony Survival Depends on Metabolic Adaptation and Cell Differentiation Rather Than on Stress Defense

    Čáp, M.; Váchová, Libuše; Palková, Z.

    2009-01-01

    Roč. 284, č. 47 (2009), s. 32572-32581 ISSN 0021-9258 R&D Projects: GA ČR GA525/05/0297; GA ČR GA204/08/0718; GA MŠk(CZ) LC531 Institutional research plan: CEZ:AV0Z50200510 Keywords : LONG-TERM SURVIVAL * SACCHAROMYCES-CEREVISIAE * SUPEROXIDE-DISMUTASE Subject RIV: EE - Microbiology, Virology Impact factor: 5.328, year: 2009

  10. Expression of S1P metabolizing enzymes and receptors correlate with survival time and regulate cell migration in glioblastoma multiforme.

    Bien-Möller, Sandra; Lange, Sandra; Holm, Tobias; Böhm, Andreas; Paland, Heiko; Küpper, Johannes; Herzog, Susann; Weitmann, Kerstin; Havemann, Christoph; Vogelgesang, Silke; Marx, Sascha; Hoffmann, Wolfgang; Schroeder, Henry W S; Rauch, Bernhard H

    2016-03-15

    A signaling molecule which is involved in proliferation and migration of malignant cells is the lipid mediator sphingosine-1-phosphate (S1P). There are hints for a potential role of S1P signaling in malignant brain tumors such as glioblastoma multiforme (GBM) which is characterized by a poor prognosis. Therefore, a comprehensive expression analysis of S1P receptors (S1P1-S1P5) and S1P metabolizing enzymes in human GBM (n = 117) compared to healthy brain (n = 10) was performed to evaluate their role for patient´s survival. Furthermore, influence of S1P receptor inhibition on proliferation and migration were studied in LN18 GBM cells. Compared to control brain, mRNA levels of S1P1, S1P2, S1P3 and S1P generating sphingosine kinase-1 were elevated in GBM. Kaplan-Meier analyses demonstrated an association between S1P1 and S1P2 with patient´s survival times. In vitro, an inhibitory effect of the SphK inhibitor SKI-II on viability of LN18 cells was shown. S1P itself had no effect on viability but stimulated LN18 migration which was blocked by inhibition of S1P1 and S1P2. The participation of S1P1 and S1P2 in LN18 migration was further supported by siRNA-mediated silencing of these receptors. Immunoblots and inhibition experiments suggest an involvement of the PI3-kinase/AKT1 pathway in the chemotactic effect of S1P in LN18 cells.In summary, our data argue for a role of S1P signaling in proliferation and migration of GBM cells. Individual components of the S1P pathway represent prognostic factors for patients with GBM. Perspectively, a selective modulation of S1P receptor subtypes could represent a therapeutic approach for GBM patients and requires further evaluation.

  11. Single-cell genomics reveal metabolic strategies for microbial growth and survival in an oligotrophic aquifer

    Wilkins, Michael J.; Kennedy, David W.; Castelle, Cindy; Field, Erin; Stepanauskas, Ramunas; Fredrickson, Jim K.; Konopka, Allan

    2014-02-09

    Bacteria from the genus Pedobacter are a major component of microbial assemblages at Hanford Site and have been shown to significantly change in abundance in response to the subsurface intrusion of Columbia River water. Here we employed single cell genomics techniques to shed light on the physiological niche of these microorganisms. Analysis of four Pedobacter single amplified genomes (SAGs) from Hanford Site sediments revealed a chemoheterotrophic lifestyle, with the potential to exist under both aerobic and microaerophilic conditions via expression of both aa3­-type and cbb3-type cytochrome c oxidases. These SAGs encoded a wide-range of both intra-and extra­-cellular carbohydrate-active enzymes, potentially enabling the degradation of recalcitrant substrates such as xylan and chitin, and the utilization of more labile sugars such as mannose and fucose. Coupled to these enzymes, a diversity of transporters and sugar-binding molecules were involved in the uptake of carbon from the extracellular local environment. The SAGs were enriched in TonB-dependent receptors (TBDRs), which play a key role in uptake of substrates resulting from degradation of recalcitrant carbon. CRISPR-Cas mechanisms for resisting viral infections were identified in all SAGs. These data demonstrate the potential mechanisms utilized for persistence by heterotrophic microorganisms in a carbon-limited aquifer, and hint at potential linkages between observed Pedobacter abundance shifts within the 300 Area subsurface and biogeochemical shifts associated with Columbia River water intrusion.

  12. Cell survival under nutrient stress is dependent on metabolic conditions regulated by Akt and not by autophagic vacuoles.

    Bruno, P; Calastretti, A; Priulla, M; Asnaghi, L; Scarlatti, F; Nicolin, A; Canti, G

    2007-10-01

    Akt activation assists tumor cell survival and promotes resistance to chemotherapy. Here we show that constitutively active Akt (CA-Akt) cells are highly sensitized to cell death induced by nutrient and growth factor deprivation, whereas dominant-negative Akt (DN-Akt) cells have a high rate of survival. The content of autophagosomes in starved CA-Akt cells was high, while DN-Akt cells expressed autophagic vacuoles constitutively, independently of nutrition conditions. Thus Akt down-regulation and downstream events can induce autophagosomes which were not directly determinants of cell death. Biochemical analysis in Akt-mutated cells show that (i) Akt and mTOR proteins were degraded more rapidly than the housekeeping proteins, (ii) mTOR phosphorylation at position Thr(2446) was relatively high in DN-Akt and low in CA-Akt cells, induced by starvation in mock cells only, which suggests reduced autoregulation of these pathways in Akt-mutated cells, (iii) both protein synthesis and protein degradation were significantly higher in starved CA-Akt cells than in starved DN-Akt cells or mock cells. In conclusion, constitutively active Akt, unable to control synthesis and wasting of proteins, accelerates the death of starved cells.

  13. Antitumor and chemosensitizing action of dichloroacetate implicates modulation of tumor microenvironment: A role of reorganized glucose metabolism, cell survival regulation and macrophage differentiation

    Kumar, Ajay; Kant, Shiva; Singh, Sukh Mahendra, E-mail: sukhmahendrasingh@yahoo.com

    2013-11-15

    Targeting of tumor metabolism is emerging as a novel therapeutic strategy against cancer. Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), has been shown to exert a potent tumoricidal action against a variety of tumor cells. The main mode of its antineoplastic action implicates a shift of glycolysis to oxidative metabolism of glucose, leading to generation of cytotoxic reactive oxygen intermediates. However, the effect of DCA on tumor microenvironment, which in turn regulates tumor cell survival; remains speculative to a large extent. It is also unclear if DCA can exert any modulatory effect on the process of hematopoiesis, which is in a compromised state in tumor-bearing hosts undergoing chemotherapy. In view of these lacunas, the present study was undertaken to investigate the so far unexplored aspects with respect to the molecular mechanisms of DCA-dependent tumor growth retardation and chemosensitization. BALB/c mice were transplanted with Dalton's lymphoma (DL) cells, a T cell lymphoma of spontaneous origin, followed by administration of DCA with or without cisplatin. DCA-dependent tumor regression and chemosensitization to cisplatin was found to be associated with altered repertoire of key cell survival regulatory molecules, modulated glucose metabolism, accompanying reconstituted tumor microenvironment with respect to pH homeostasis, cytokine balance and alternatively activated TAM. Moreover, DCA administration also led to an alteration in the MDR phenotype of tumor cells and myelopoietic differentiation of macrophages. The findings of this study shed a new light with respect to some of the novel mechanisms underlying the antitumor action of DCA and thus may have immense clinical applications. - Highlights: • DCA modulates tumor progression and chemoresistance. • DCA alters molecules regulating cell survival, glucose metabolism and MDR. • DCA reconstitutes biophysical and cellular composition of tumor microenvironment.

  14. Antitumor and chemosensitizing action of dichloroacetate implicates modulation of tumor microenvironment: A role of reorganized glucose metabolism, cell survival regulation and macrophage differentiation

    Kumar, Ajay; Kant, Shiva; Singh, Sukh Mahendra

    2013-01-01

    Targeting of tumor metabolism is emerging as a novel therapeutic strategy against cancer. Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), has been shown to exert a potent tumoricidal action against a variety of tumor cells. The main mode of its antineoplastic action implicates a shift of glycolysis to oxidative metabolism of glucose, leading to generation of cytotoxic reactive oxygen intermediates. However, the effect of DCA on tumor microenvironment, which in turn regulates tumor cell survival; remains speculative to a large extent. It is also unclear if DCA can exert any modulatory effect on the process of hematopoiesis, which is in a compromised state in tumor-bearing hosts undergoing chemotherapy. In view of these lacunas, the present study was undertaken to investigate the so far unexplored aspects with respect to the molecular mechanisms of DCA-dependent tumor growth retardation and chemosensitization. BALB/c mice were transplanted with Dalton's lymphoma (DL) cells, a T cell lymphoma of spontaneous origin, followed by administration of DCA with or without cisplatin. DCA-dependent tumor regression and chemosensitization to cisplatin was found to be associated with altered repertoire of key cell survival regulatory molecules, modulated glucose metabolism, accompanying reconstituted tumor microenvironment with respect to pH homeostasis, cytokine balance and alternatively activated TAM. Moreover, DCA administration also led to an alteration in the MDR phenotype of tumor cells and myelopoietic differentiation of macrophages. The findings of this study shed a new light with respect to some of the novel mechanisms underlying the antitumor action of DCA and thus may have immense clinical applications. - Highlights: • DCA modulates tumor progression and chemoresistance. • DCA alters molecules regulating cell survival, glucose metabolism and MDR. • DCA reconstitutes biophysical and cellular composition of tumor microenvironment.

  15. NDRG2 overexpression suppresses hepatoma cells survival during metabolic stress through disturbing the activation of fatty acid oxidation

    Pan, Tao; Zhang, Mei; Zhang, Fang; Yan, Guang; Ru, Yi; Wang, Qinhao; Zhang, Yao; Wei, Xuehui; Xu, Xinyuan; Shen, Lan; Zhang, Jian; Wu, Kaichun; Yao, Libo; Li, Xia

    2017-01-01

    Because of the high nutrient consumption and inadequate vascularization, solid tumor constantly undergoes metabolic stress during tumor development. Oncogenes and tumor suppressor genes participated in cancer cells' metabolic reprogramming. N-Myc downstream regulated gene 2 (NDRG2) is a recently identified tumor suppressor gene, but its function in cancer metabolism, particularly during metabolic stress, remains unclear. In this study, we found that NDRG2 overexpression significantly reduced hepatoma cell proliferation and enhanced cell apoptosis under glucose limitation. Moreover, NDRG2 overexpression aggravated energy imbalance and oxidative stress by decreasing the intracellular ATP and NADPH generation and increasing ROS levels. Strikingly, NDRG2 inhibited the activation of fatty acid oxidation (FAO), which preserves ATP and NADPH purveyance in the absence of glucose. Finally, mechanistic investigation showed that NDRG2 overexpression suppressed the glucose-deprivation induced AMPK/ACC pathway activation in hepatoma cells, whereas the expression of a constitutively active form of AMPK abrogated glucose-deprivation induced AMPK activation and cell apoptosis. Thus, as a negative regulator of AMPK, NDRG2 disturbs the induction of FAO genes by glucose limitation, leading to dysregulation of ATP and NADPH, and thus reduces the tolerance of hepatoma cells to glucose limitation. - Highlights: • NDRG2 overexpression reduces the tolerance of hepatoma cells to glucose limitation. • NDRG2 overexpression aggravates energy imbalance and oxidative stress under glucose deprivation. • NDRG2 overexpression disturbs the activation of FAO in hepatoma cells under glucose limitation. • NDRG2 overexpression inhibits the activation of AMPK/ACC pathway in hepatoma cells during glucose starvation.

  16. Radiobilogical cell survival models

    Zackrisson, B.

    1992-01-01

    A central issue in clinical radiobiological research is the prediction of responses to different radiation qualities. The choice of cell survival and dose-response model greatly influences the results. In this context the relationship between theory and model is emphasized. Generally, the interpretations of experimental data depend on the model. Cell survival models are systematized with respect to their relations to radiobiological theories of cell kill. The growing knowlegde of biological, physical, and chemical mechanisms is reflected in the formulation of new models. The present overview shows that recent modelling has been more oriented towards the stochastic fluctuations connected to radiation energy deposition. This implies that the traditional cell surivival models ought to be complemented by models of stochastic energy deposition processes and repair processes at the intracellular level. (orig.)

  17. Survival prognostic value of morphological and metabolic variables in patients with stage I and II non-small cell lung cancer

    Domachevsky, L. [Rabin Medical Center, Department of Nuclear Medicine, Petah Tikva (Israel); Beilinson Hospital, Petah Tikva (Israel); Groshar, D.; Bernstine, H. [Rabin Medical Center, Department of Nuclear Medicine, Petah Tikva (Israel); Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv (Israel); Galili, R. [Lady Davis-Carmel Medical Center, Department of Cardiothoracic Surgery, Haifa (Israel); Saute, M. [Rabin Medical Center, Department of Cardiothoracic Surgery, Petah Tiqva (Israel)

    2015-11-15

    The prognosis of patients with non-small cell lung cancer (NSCLC) is important, as patients with resectable disease and poor prognostic variables might benefit from neoadjuvant therapy. The goal of this study is to evaluate SUVmax, SUVmax ratio, CT volume (CTvol), metabolic tumour volume (MTV) and total lesion glycolisis (TLG) as survival prognostic markers. In addition, we defined two variables; MTV x SUVmax (MTVmax) and CTvol x SUVmax (CTvolmax) and assessed whether they can be used as prognostic markers. Patients with stage I-II NSCLC who underwent 18 F FDG PET/CT and surgery were evaluated. Cox proportional-hazard model was used to determine the association between variables and survival. Similar analysis was performed in cases with no lymph node (LN) involvement. One hundred and eighty-one patients were included (at the end of the study, 140 patients were alive). SUVmax with a cut-off value of 8.2 was significant survival prognostic factor regardless of LN involvement (P = 0.012). In cases with no LN involvement, SUVmax and CTvol (≥7.1 ml) were significant survival prognostic factors with P = 0.004 and 0.03, respectively. SUVmax may be a useful prognostic variable in stage I-II NSCLC while morphologic tumour volume might be useful in cases with no lymph node involvement. (orig.)

  18. Survival curves for irradiated cells

    Gibson, D.K.

    1975-01-01

    The subject of the lecture is the probability of survival of biological cells which have been subjected to ionising radiation. The basic mathematical theories of cell survival as a function of radiation dose are developed. A brief comparison with observed survival curves is made. (author)

  19. Zinc finger nuclease mediated knockout of ADP-dependent glucokinase in cancer cell lines: effects on cell survival and mitochondrial oxidative metabolism.

    Susan Richter

    Full Text Available Zinc finger nucleases (ZFN are powerful tools for editing genes in cells. Here we use ZFNs to interrogate the biological function of ADPGK, which encodes an ADP-dependent glucokinase (ADPGK, in human tumour cell lines. The hypothesis we tested is that ADPGK utilises ADP to phosphorylate glucose under conditions where ATP becomes limiting, such as hypoxia. We characterised two ZFN knockout clones in each of two lines (H460 and HCT116. All four clones had frameshift mutations in all alleles at the target site in exon 1 of ADPGK, and were ADPGK-null by immunoblotting. ADPGK knockout had little or no effect on cell proliferation, but compromised the ability of H460 cells to survive siRNA silencing of hexokinase-2 under oxic conditions, with clonogenic survival falling from 21±3% for the parental line to 6.4±0.8% (p = 0.002 and 4.3±0.8% (p = 0.001 for the two knockouts. A similar increased sensitivity to clonogenic cell killing was observed under anoxia. No such changes were found when ADPGK was knocked out in HCT116 cells, for which the parental line was less sensitive than H460 to anoxia and to hexokinase-2 silencing. While knockout of ADPGK in HCT116 cells caused few changes in global gene expression, knockout of ADPGK in H460 cells caused notable up-regulation of mRNAs encoding cell adhesion proteins. Surprisingly, we could discern no consistent effect on glycolysis as measured by glucose consumption or lactate formation under anoxia, or extracellular acidification rate (Seahorse XF analyser under oxic conditions in a variety of media. However, oxygen consumption rates were generally lower in the ADPGK knockouts, in some cases markedly so. Collectively, the results demonstrate that ADPGK can contribute to tumour cell survival under conditions of high glycolytic dependence, but the phenotype resulting from knockout of ADPGK is cell line dependent and appears to be unrelated to priming of glycolysis in these lines.

  20. Zinc finger nuclease mediated knockout of ADP-dependent glucokinase in cancer cell lines: effects on cell survival and mitochondrial oxidative metabolism.

    Richter, Susan; Morrison, Shona; Connor, Tim; Su, Jiechuang; Print, Cristin G; Ronimus, Ron S; McGee, Sean L; Wilson, William R

    2013-01-01

    Zinc finger nucleases (ZFN) are powerful tools for editing genes in cells. Here we use ZFNs to interrogate the biological function of ADPGK, which encodes an ADP-dependent glucokinase (ADPGK), in human tumour cell lines. The hypothesis we tested is that ADPGK utilises ADP to phosphorylate glucose under conditions where ATP becomes limiting, such as hypoxia. We characterised two ZFN knockout clones in each of two lines (H460 and HCT116). All four clones had frameshift mutations in all alleles at the target site in exon 1 of ADPGK, and were ADPGK-null by immunoblotting. ADPGK knockout had little or no effect on cell proliferation, but compromised the ability of H460 cells to survive siRNA silencing of hexokinase-2 under oxic conditions, with clonogenic survival falling from 21±3% for the parental line to 6.4±0.8% (p = 0.002) and 4.3±0.8% (p = 0.001) for the two knockouts. A similar increased sensitivity to clonogenic cell killing was observed under anoxia. No such changes were found when ADPGK was knocked out in HCT116 cells, for which the parental line was less sensitive than H460 to anoxia and to hexokinase-2 silencing. While knockout of ADPGK in HCT116 cells caused few changes in global gene expression, knockout of ADPGK in H460 cells caused notable up-regulation of mRNAs encoding cell adhesion proteins. Surprisingly, we could discern no consistent effect on glycolysis as measured by glucose consumption or lactate formation under anoxia, or extracellular acidification rate (Seahorse XF analyser) under oxic conditions in a variety of media. However, oxygen consumption rates were generally lower in the ADPGK knockouts, in some cases markedly so. Collectively, the results demonstrate that ADPGK can contribute to tumour cell survival under conditions of high glycolytic dependence, but the phenotype resulting from knockout of ADPGK is cell line dependent and appears to be unrelated to priming of glycolysis in these lines.

  1. Radionuclide blood cell survival studies

    Bentley, S.A.; Miller, D.T.

    1986-01-01

    Platelet and red cell survival studies are reviewed. The use of 51 Cr and di-isopropylfluoridate labelled with tritium or 32 P is discussed for red cell survival study and 51 Cr and 111 In-oxine are considered as platelet labels. (UK)

  2. Stimulated human fibroblast cell survival

    Smith, B.P.; Gale, K.L.; Einspenner, M.; Greenstock, C.L.; Gentner, N.E.

    1992-01-01

    Techniques for cloning cultured mammalian cells have supported the most universally-accepted method for measuring the induction of lethality by geno-toxicants such as ionizing radiation: the 'survival of colony-forming ability (CFA)' assay. Since most cultured human cell lines exhibit plating efficiency (i.e. the percentage of cells that are capable of reproductively surviving and dividing to form visible colonies) well below 100%, such assays are in essence 'survival of plating efficiency' assays, since they are referred to the plating (or cloning) efficiency of control (i.e. unirradiated) cells. (author). 8 refs., 2 figs

  3. AMPK regulates metabolism and survival in response to ionizing radiation

    Zannella, Vanessa E.; Cojocari, Dan; Hilgendorf, Susan; Vellanki, Ravi N.; Chung, Stephen; Wouters, Bradly G.; Koritzinsky, Marianne

    2011-01-01

    Background and purpose: AMPK is a metabolic sensor and an upstream inhibitor of mTOR activity. AMPK is phosphorylated by ionizing radiation (IR) in an ATM dependent manner, but the cellular consequences of this phosphorylation event have remained unclear. The objective of this study was to assess whether AMPK plays a functional role in regulating cellular responses to IR. Methods: The importance of AMPK expression for radiation responses was investigated using both MEFs (mouse embryo fibroblasts) double knockout for AMPK α1/α2 subunits and human colorectal carcinoma cells (HCT 116) with AMPK α1/α2 shRNA mediated knockdown. Results: We demonstrate here that IR results in phosphorylation of both AMPK and its substrate, ACC. IR moderately stimulated mTOR activity, and this was substantially exacerbated in the absence of AMPK. AMPK was required for IR induced expression of the mTOR inhibitor REDD1, indicating that AMPK restrains mTOR activity through multiple mechanisms. Likewise, cellular metabolism was deregulated following irradiation in the absence of AMPK, as evidenced by a substantial increase in oxygen consumption rates and lactate production. AMPK deficient cells showed impairment of the G1/S cell cycle checkpoint, and were unable to support long-term proliferation during starvation following radiation. Lastly, we show that AMPK proficiency is important for clonogenic survival after radiation during starvation. Conclusions: These data reveal novel functional roles for AMPK in regulating mTOR signaling, cell cycle, survival and metabolic responses to IR.

  4. SHMT2 drives glioma cell survival in ischaemia but imposes a dependence on glycine clearance.

    Kim, D.; Fiske, B.P.; Birsoy, K.; Freinkman, E.; Kami, K.; Possemato, R.L.; Chudnovsky, Y.; Pacold, M.E.; Chen, W.W.; Cantor, J.R.; Shelton, L.M.; Gui, D.Y.; Kwon, M.; Ramkissoon, S.H.; Ligon, K.L.; Kang, S.W.; Snuderl, M.; der Heiden, M.G. Van; Sabatini, D.M.

    2015-01-01

    Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumour microenvironment. Here we identify a key role for serine and glycine metabolism in the survival of brain

  5. Cell Survival Signaling in Neuroblastoma

    Megison, Michael L.; Gillory, Lauren A.; Beierle, Elizabeth A.

    2013-01-01

    Neuroblastoma is the most common extracranial solid tumor of childhood and is responsible for over 15% of pediatric cancer deaths. Neuroblastoma tumorigenesis and malignant transformation is driven by overexpression and dominance of cell survival pathways and a lack of normal cellular senescence or apoptosis. Therefore, manipulation of cell survival pathways may decrease the malignant potential of these tumors and provide avenues for the development of novel therapeutics. This review focuses on several facets of cell survival pathways including protein kinases (PI3K, AKT, ALK, and FAK), transcription factors (NF-κB, MYCN and p53), and growth factors (IGF, EGF, PDGF, and VEGF). Modulation of each of these factors decreases the growth or otherwise hinders the malignant potential of neuroblastoma, and many therapeutics targeting these pathways are already in the clinical trial phase of development. Continued research and discovery of effective modulators of these pathways will revolutionize the treatment of neuroblastoma. PMID:22934706

  6. Acetyl-CoA carboxylase rewires cancer metabolism to allow cancer cells to survive inhibition of the Warburg effect by cetuximab.

    Luo, Jingtao; Hong, Yun; Lu, Yang; Qiu, Songbo; Chaganty, Bharat K R; Zhang, Lun; Wang, Xudong; Li, Qiang; Fan, Zhen

    2017-01-01

    Cetuximab inhibits HIF-1-regulated glycolysis in cancer cells, thereby reversing the Warburg effect and leading to inhibition of cancer cell metabolism. AMP-activated protein kinase (AMPK) is activated after cetuximab treatment, and a sustained AMPK activity is a mechanism contributing to cetuximab resistance. Here, we investigated how acetyl-CoA carboxylase (ACC), a downstream target of AMPK, rewires cancer metabolism in response to cetuximab treatment. We found that introduction of experimental ACC mutants lacking the AMPK phosphorylation sites (ACC1_S79A and ACC2_S212A) into head and neck squamous cell carcinoma (HNSCC) cells protected HNSCC cells from cetuximab-induced growth inhibition. HNSCC cells with acquired cetuximab resistance contained not only high levels of T172-phosphorylated AMPK and S79-phosphorylated ACC1 but also an increased level of total ACC. These findings were corroborated in tumor specimens of HNSCC patients treated with cetuximab. Cetuximab plus TOFA (an allosteric inhibitor of ACC) achieved remarkable growth inhibition of cetuximab-resistant HNSCC xenografts. Our data suggest a novel paradigm in which cetuximab-mediated activation of AMPK and subsequent phosphorylation and inhibition of ACC is followed by a compensatory increase in total ACC, which rewires cancer metabolism from glycolysis-dependent to lipogenesis-dependent. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Snail modulates cell metabolism in MDCK cells

    Haraguchi, Misako, E-mail: haraguci@m3.kufm.kagoshima-u.ac.jp [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Indo, Hiroko P. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Iwasaki, Yasumasa [Health Care Center, Kochi University, Kochi 780-8520 (Japan); Iwashita, Yoichiro [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Fukushige, Tomoko [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Majima, Hideyuki J. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Izumo, Kimiko; Horiuchi, Masahisa [Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Kanekura, Takuro [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Furukawa, Tatsuhiko [Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Ozawa, Masayuki [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan)

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  8. The Role of Lipid Metabolism in T Lymphocyte Differentiation and Survival

    Duncan Howie

    2018-01-01

    Full Text Available The differentiation and effector functions of both the innate and adaptive immune system are inextricably linked to cellular metabolism. The features of metabolism which affect both arms of the immune system include metabolic substrate availability, expression of enzymes, transport proteins, and transcription factors which control catabolism of these substrates, and the ability to perform anabolic metabolism. The control of lipid metabolism is central to the appropriate differentiation and functions of T lymphocytes, and ultimately to the maintenance of immune tolerance. This review will focus on the role of fatty acid (FA metabolism in T cell differentiation, effector function, and survival. FAs are important sources of cellular energy, stored as triglycerides. They are also used as precursors to produce complex lipids such as cholesterol and membrane phospholipids. FA residues also become incorporated into hormones and signaling moieties. FAs signal via nuclear receptors and their channeling, between storage as triacyl glycerides or oxidation as fuel, may play a role in survival or death of the cell. In recent years, progress in the field of immunometabolism has highlighted diverse roles for FA metabolism in CD4 and CD8 T cell differentiation and function. This review will firstly describe the sensing and modulation of the environmental FAs and lipid intracellular signaling and will then explore the key role of lipid metabolism in regulating the balance between potentially damaging pro-inflammatory and anti-inflammatory regulatory responses. Finally the complex role of extracellular FAs in determining cell survival will be discussed.

  9. Early prediction of therapy response and disease free survival after induction chemotherapy in stage III non-small cell lung cancer by FDG-PET: Correlation between tumor FDG-metabolism and morphometric tumor response

    Baum, R.P.; Schmuecking, M.; Niesen, A.; Przetak, C.; Griesinger, F.

    2002-01-01

    Aim: Chemotherapy with Docetaxel and Carboplatin (DC) has shown high response rates in advanced non-small cell lung cancer (NSCLC). Histologic tumor response after chemotherapy or combined chemoradiotherapy is strongly associated with systemic tumor control and potentially cure. Metabolic tumor response assessed by FDG-PET after induction VIP-chemotherapy has been shown to be predictive of outcome in NSCLC. The aim of the present study was to correlate the tumor FDG metabolism as measured by F-18 FDG-PET with morphometric findings after DC induction chemotherapy plus Erythropoietin (10,000 IU Epo s.c. three times a week). Material and Methods: In this prospective multicenter study, 54 patients with NSCLC stage IIIA (9 patients) or IIIB (45 patients) were enrolled and received neoadjuvant treatment with D 100 mg/m 2 d1 and C AUC 7.5 d2 q21 days for 4 cycles prior to surgery. Postoperatively, all patients received adjuvant radiotherapy. WB-PET-studies (ECAT Exact 47) were obtained p.i. of 400 MBq F-18 FDG. Standardized uptake values (SUV), metabolic tumor diameter (MTD) and metabolic tumor index (MTI SUV x MTD) were assessed. Image fusion of PET and CT data was applied on a HERMES computer. Results: Of 54 enrolled patients, 46 were evaluable for response by CT. 30/46 patients (65%) achieved complete remission (CR, 1 patient) or partial remission (PR 29 patients.). Of the 46 patients, 37 patients completed neoadjuvant chemotherapy (Chx) and were studied before and after Chx by FDG-PET. 14 (30% of the 46 evaluable patients) had SUV < 2.5, corresponding to metabolic complete remission (mCR), 23 had PR or stable disease (non-mCR); in 9 patients, PET was not performed because of progressive disease demonstrated by CT. The R0-resection rate was 56% (27/48 evaluable patients). Of the 14 patients with metabolic CR, 9 were evaluated by morphometry. All had regression grades III (no vital tumor cells) or grade IIB (< 10% vital tumor cells and induced apoptosis). With a median

  10. Triiodothyronine regulates cell growth and survival in renal cell cancer.

    Czarnecka, Anna M; Matak, Damian; Szymanski, Lukasz; Czarnecka, Karolina H; Lewicki, Slawomir; Zdanowski, Robert; Brzezianska-Lasota, Ewa; Szczylik, Cezary

    2016-10-01

    Triiodothyronine plays an important role in the regulation of kidney cell growth, differentiation and metabolism. Patients with renal cell cancer who develop hypothyreosis during tyrosine kinase inhibitor (TKI) treatment have statistically longer survival. In this study, we developed cell based model of triiodothyronine (T3) analysis in RCC and we show the different effects of T3 on renal cell cancer (RCC) cell growth response and expression of the thyroid hormone receptor in human renal cell cancer cell lines from primary and metastatic tumors along with human kidney cancer stem cells. Wild-type thyroid hormone receptor is ubiquitously expressed in human renal cancer cell lines, but normalized against healthy renal proximal tube cell expression its level is upregulated in Caki-2, RCC6, SKRC-42, SKRC-45 cell lines. On the contrary the mRNA level in the 769-P, ACHN, HKCSC, and HEK293 cells is significantly decreased. The TRβ protein was abundant in the cytoplasm of the 786-O, Caki-2, RCC6, and SKRC-45 cells and in the nucleus of SKRC-42, ACHN, 769-P and cancer stem cells. T3 has promoting effect on the cell proliferation of HKCSC, Caki-2, ASE, ACHN, SK-RC-42, SMKT-R2, Caki-1, 786-0, and SK-RC-45 cells. Tyrosine kinase inhibitor, sunitinib, directly inhibits proliferation of RCC cells, while thyroid hormone receptor antagonist 1-850 (CAS 251310‑57-3) has less significant inhibitory impact. T3 stimulation does not abrogate inhibitory effect of sunitinib. Renal cancer tumor cells hypostimulated with T3 may be more responsive to tyrosine kinase inhibition. Moreover, some tumors may be considered as T3-independent and present aggressive phenotype with thyroid hormone receptor activated independently from the ligand. On the contrary proliferation induced by deregulated VHL and or c-Met pathways may transgress normal T3 mediated regulation of the cell cycle.

  11. Brucella abortus Induces a Warburg Shift in Host Metabolism That Is Linked to Enhanced Intracellular Survival of the Pathogen.

    Czyż, Daniel M; Willett, Jonathan W; Crosson, Sean

    2017-08-01

    Intracellular bacterial pathogens exploit host cell resources to replicate and survive inside the host. Targeting these host systems is one promising approach to developing novel antimicrobials to treat intracellular infections. We show that human macrophage-like cells infected with Brucella abortus undergo a metabolic shift characterized by attenuated tricarboxylic acid cycle metabolism, reduced amino acid consumption, altered mitochondrial localization, and increased lactate production. This shift to an aerobic glycolytic state resembles the Warburg effect, a change in energy production that is well described in cancer cells and also occurs in activated inflammatory cells. B. abortus efficiently uses lactic acid as its sole carbon and energy source and requires the ability to metabolize lactate for normal survival in human macrophage-like cells. We demonstrate that chemical inhibitors of host glycolysis and lactate production do not affect in vitro growth of B. abortus in axenic culture but decrease its survival in the intracellular niche. Our data support a model in which infection shifts host metabolism to a Warburg-like state, and B. abortus uses this change in metabolism to promote intracellular survival. Pharmacological perturbation of these features of host cell metabolism may be a useful strategy to inhibit infection by intracellular pathogens. IMPORTANCE Brucella spp. are intracellular bacterial pathogens that cause disease in a range of mammals, including livestock. Transmission from livestock to humans is common and can lead to chronic human disease. Human macrophage-like cells infected with Brucella abortus undergo a Warburg-like metabolic shift to an aerobic glycolytic state where the host cells produce lactic acid and have reduced amino acid catabolism. We provide evidence that the pathogen can exploit this change in host metabolism to support growth and survival in the intracellular niche. Drugs that inhibit this shift in host cell metabolism

  12. The prognostic value of metabolic tumor volume in FDG PET/CT evaluation of post-operative survival in patients with esophageal squamous cell cancer

    Zhu Wanqi; Yu Jinming; Sun Xiaorong; Xing Ligang; Xie Peng; Sun Xindong; Guo Hongbo; Yang Guoren; Kong Li

    2011-01-01

    Objective: To evaluate the prognostic value of MTV on 18 F-FDG PET/CT in patients with esophageal cancer. Methods: Forty-nine patients with esophageal cancer underwent 18 F-FDG PET/CT scan before surgery. The median follow-up time for the patients was 29 months (range, 8-57 months). The prognostic significance of MTV, age, sex, histologic grade, SUV max of the primary tumor, tumor size measured on PET/CT, T stage, N stage, M stage, American Joint Committee on Cancer (AJCC) stage, number and location of lymph nodes metastases were assessed by Kaplan-Meier analysis and multivariate Cox model. Results: In the univariate analysis, AJCC stage (χ 2 =16.206, hazard ratio (HR)=1.177, P<0.001), N stage (χ 2 =9.536, HR=10.833, P=0.002), T stage (χ 2 =5.810, HR=2.397, P=0.016), number of lymph nodes metastases (χ 2 =11.423, HR=1.567, P=0.001), and MTV (χ 2 =3.872, HR=2.433, P=0.049) were significant predictors of survival.Multivariate analysis showed that MTV and AJCC stage were independent predictors of survival (χ 2 =4.525, HR 1.170, P=0.033; χ 2 =4.875, HR=3.071, P=0.027). Kaplan-Meier survival curves revealed longer survival time of low-MTV group as compared to high-MTV group (Log-rank, χ 2 =4.186, P=0.041). Conclusion: MTV on 18 F-FDG PET/CT may be an independent prognostic factor in patients with esophageal cancer. (authors)

  13. Metabolic reprogramming in the tumour microenvironment: a hallmark shared by cancer cells and T lymphocytes.

    Allison, Katrina E; Coomber, Brenda L; Bridle, Byram W

    2017-10-01

    Altered metabolism is a hallmark of cancers, including shifting oxidative phosphorylation to glycolysis and up-regulating glutaminolysis to divert carbon sources into biosynthetic pathways that promote proliferation and survival. Therefore, metabolic inhibitors represent promising anti-cancer drugs. However, T cells must rapidly divide and survive in harsh microenvironments to mediate anti-cancer effects. Metabolic profiles of cancer cells and activated T lymphocytes are similar, raising the risk of metabolic inhibitors impairing the immune system. Immune checkpoint blockade provides an example of how metabolism can be differentially impacted to impair cancer cells but support T cells. Implications for research with metabolic inhibitors are discussed. © 2017 John Wiley & Sons Ltd.

  14. Tracking plasma cell differentiation and survival.

    Roth, Katrin; Oehme, Laura; Zehentmeier, Sandra; Zhang, Yang; Niesner, Raluca; Hauser, Anja E

    2014-01-01

    Plasma cells play a crucial role for the humoral immune response as they represent the body's factories for antibody production. The differentiation from a B cell into a plasma cell is controlled by a complex transcriptional network and happens within secondary lymphoid organs. Based on their lifetime, two types of antibody secreting cells can be distinguished: Short-lived plasma cells are located in extrafollicular sites of secondary lymphoid organs such as lymph node medullary cords and the splenic red pulp. A fraction of plasmablasts migrate from secondary lymphoid organs to the bone marrow where they can become long-lived plasma cells. Bone marrow plasma cells reside in special microanatomical environments termed survival niches, which provide factors promoting their longevity. Reticular stromal cells producing the chemokine CXCL12, which is known to attract plasmablasts to the bone marrow but also to promote plasma cell survival, play a crucial role in the maintenance of these niches. In addition, hematopoietic cells are contributing to the niches by providing other soluble survival factors. Here, we review the current knowledge on the factors involved in plasma cell differentiation, their localization and migration. We also give an overview on what is known regarding the maintenance of long lived plasma cells in survival niches of the bone marrow. © 2013 International Society for Advancement of Cytometry.

  15. The statistical treatment of cell survival data

    Boag, J.W.

    1975-01-01

    The paper considers the sources of experimental error in cell survival experiments and discusses in simple terms how these combine to influence the accuracy of single points and the parameters of complete survival curves. Cell sampling and medium-dilution errors are discussed at length and one way of minimizing the former is examined. The Monte-Carlo method of estimating the distribution of derived parameters in small samples is recommended and illustrated. (author)

  16. Metabolism during ECM Detachment: Achilles Heel of Cancer Cells?

    Mason, Joshua A; Hagel, Kimberly R; Hawk, Mark A; Schafer, Zachary T

    2017-07-01

    Integrin-mediated attachment to the extracellular matrix (ECM) is required to combat the induction of programmed cell death in a variety of distinct cell types. If cells fail to maintain proper ECM attachment, they become subject to elimination via an apoptotic cell death program known as anoikis. However, anoikis inhibition is not sufficient to promote the long-term survival of ECM-detached cells. Several recent studies have unveiled the profound (anoikis-independent) impact of cell metabolism on the viability of ECM-detached cells. Thus, we posit that, during metastatic dissemination (when cancer cells are exposed to periods of ECM detachment), cancer cells must alter their metabolism in a fashion that promotes survival and ultimately contributes to metastatic outgrowth. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. INO80 Chromatin Remodeling Coordinates Metabolic Homeostasis with Cell Division

    Graeme J. Gowans

    2018-01-01

    Full Text Available Adaptive survival requires the coordination of nutrient availability with expenditure of cellular resources. For example, in nutrient-limited environments, 50% of all S. cerevisiae genes synchronize and exhibit periodic bursts of expression in coordination with respiration and cell division in the yeast metabolic cycle (YMC. Despite the importance of metabolic and proliferative synchrony, the majority of YMC regulators are currently unknown. Here, we demonstrate that the INO80 chromatin-remodeling complex is required to coordinate respiration and cell division with periodic gene expression. Specifically, INO80 mutants have severe defects in oxygen consumption and promiscuous cell division that is no longer coupled with metabolic status. In mutant cells, chromatin accessibility of periodic genes, including TORC1-responsive genes, is relatively static, concomitant with severely attenuated gene expression. Collectively, these results reveal that the INO80 complex mediates metabolic signaling to chromatin to restrict proliferation to metabolically optimal states.

  18. Cell survival studies using ultrasoft x rays

    Schillaci, M.E.; Raju, M.R.; Carpenter, S.; Cornforth, M.; Wilder, M.

    1987-01-01

    Cell survival was studied for V79 hamster, 10T1/2 mouse, and human skin fibroblast cell lines, using carbon K (0.28 keV), copper K (8.0 keV), and 250 kVp x rays. Because of the rapid attenuation of the carbon x rays, cellular dimensions at the time of exposure were measured using optical and electron microscopy, and frequency distributions of mean dose absorbed by the cell nucleus were obtained. The results indicate that the differences in cell killing between ultra-soft and hard x rays may depend on the nuclear thickness of the cells. Studies of the effects of hypoxia on V79 and 10T1/2 cells using carbon K, aluminum K (1.5 keV), and copper K x rays show decreasing OER values with decreasing x-ray energy and no difference between the two cell lines. Age response studies with V79 cells show similar cell-cycle variation of survival for carbon K and aluminum K x rays as for hard x rays

  19. Cancer Cell Metabolism: One Hallmark, Many Faces

    Cantor, Jason R.; Sabatini, David M.

    2012-01-01

    Cancer cells must rewire cellular metabolism to satisfy the demands of growth and proliferation. Although many of the metabolic alterations are largely similar to those in normal proliferating cells, they are aberrantly driven in cancer by a combination of genetic lesions and nongenetic factors such as the tumor microenvironment. However, a single model of altered tumor metabolism does not describe the sum of metabolic changes that can support cell growth. Instead, the diversity of such chang...

  20. Is the rate of metabolic ageing and survival determined by Basal metabolic rate in the zebra finch?

    Bernt Rønning

    Full Text Available The relationship between energy metabolism and ageing is of great interest because aerobic metabolism is the primary source of reactive oxygen species which is believed to be of major importance in the ageing process. We conducted a longitudinal study on captive zebra finches where we tested the effect of age on basal metabolic rate (BMR, as well as the effect of BMR on the rate of metabolic ageing (decline in BMR with age and survival. Basal metabolic rate declined with age in both sexes after controlling for the effect of body mass, indicating a loss of functionality with age. This loss of functionality could be due to accumulated oxidative damage, believed to increase with increasing metabolic rate, c.f. the free radical theory of ageing. If so, we would expect the rate of metabolic ageing to increase and survival to decrease with increasing BMR. However, we found no effect of BMR on the rate of metabolic ageing. Furthermore, survival was not affected by BMR in the males. In female zebra finches there was a tendency for survival to decrease with increasing BMR, but the effect did not reach significance (P<0.1. Thus, the effect of BMR on the rate of functional deterioration with age, if any, was not strong enough to influence neither the rate of metabolic ageing nor survival in the zebra finches.

  1. Is the rate of metabolic ageing and survival determined by Basal metabolic rate in the zebra finch?

    Rønning, Bernt; Moe, Børge; Berntsen, Henrik H; Noreen, Elin; Bech, Claus

    2014-01-01

    The relationship between energy metabolism and ageing is of great interest because aerobic metabolism is the primary source of reactive oxygen species which is believed to be of major importance in the ageing process. We conducted a longitudinal study on captive zebra finches where we tested the effect of age on basal metabolic rate (BMR), as well as the effect of BMR on the rate of metabolic ageing (decline in BMR with age) and survival. Basal metabolic rate declined with age in both sexes after controlling for the effect of body mass, indicating a loss of functionality with age. This loss of functionality could be due to accumulated oxidative damage, believed to increase with increasing metabolic rate, c.f. the free radical theory of ageing. If so, we would expect the rate of metabolic ageing to increase and survival to decrease with increasing BMR. However, we found no effect of BMR on the rate of metabolic ageing. Furthermore, survival was not affected by BMR in the males. In female zebra finches there was a tendency for survival to decrease with increasing BMR, but the effect did not reach significance (PBMR on the rate of functional deterioration with age, if any, was not strong enough to influence neither the rate of metabolic ageing nor survival in the zebra finches.

  2. Melphalan metabolism in cultured cells

    Seagrave, J.C.; Valdez, J.G.; Tobey, R.A.; Gurley, L.R.

    1985-06-01

    Procedures are presented for the adaptation of reversed-phase-HPLC methods to accomplish separation and isolation of the cancer therapeutic drug melphalan (L-phenylalanine mustard) and its metabolic products from whole cells. Five major degradation products of melphalan were observed following its hydrolysis in phosphate buffer in vitro. The two most polar of these products (or modifications of them) were also found in the cytosol of Chinese hamster CHO cells. The amounts of these two polar products (shown not to be mono- or dihydroxymelphalan) were significantly changed by the pretreatment of cells with ZnC1 2 , one being increased in amount while the other was reduced to an insignificant level. In ZnC1 2 -treated cells, there was also an increased binding of melphalan (or its derivatives) to one protein fraction resolved by gel filtration-HPLC. These observations suggest that changes in polar melphalan products, and perhaps their interaction with a protein, may by involved in the reduction of melphalan cytotoxicity observed in ZnC1 2 -treated cells. While ZnC1 2 is also known to increase the level of glutathione in cells, no significant amounts of glutathione-melphalan derivatives of the type formed non-enzymatically in vitro could be detected in ZnC1 2 -treated or untreated cells. Formation of derivatives of melphalan with glutathione catabolic products in ZnC1 2 -treated cells has not yet been eliminated, however. 17 refs., 5 figs., 1 tab

  3. Ovarian tumor-initiating cells display a flexible metabolism

    Anderson, Angela S. [Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA (United States); Roberts, Paul C. [Biomedical Science and Pathobiology, Virginia Tech, Blacksburg, VA (United States); Frisard, Madlyn I. [Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA (United States); Hulver, Matthew W., E-mail: hulvermw@vt.edu [Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA (United States); Schmelz, Eva M., E-mail: eschmelz@vt.edu [Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA (United States)

    2014-10-15

    An altered metabolism during ovarian cancer progression allows for increased macromolecular synthesis and unrestrained growth. However, the metabolic phenotype of cancer stem or tumor-initiating cells, small tumor cell populations that are able to recapitulate the original tumor, has not been well characterized. In the present study, we compared the metabolic phenotype of the stem cell enriched cell variant, MOSE-L{sub FFLv} (TIC), derived from mouse ovarian surface epithelial (MOSE) cells, to their parental (MOSE-L) and benign precursor (MOSE-E) cells. TICs exhibit a decrease in glucose and fatty acid oxidation with a concomitant increase in lactate secretion. In contrast to MOSE-L cells, TICs can increase their rate of glycolysis to overcome the inhibition of ATP synthase by oligomycin and can increase their oxygen consumption rate to maintain proton motive force when uncoupled, similar to the benign MOSE-E cells. TICs have an increased survival rate under limiting conditions as well as an increased survival rate when treated with AICAR, but exhibit a higher sensitivity to metformin than MOSE-E and MOSE-L cells. Together, our data show that TICs have a distinct metabolic profile that may render them flexible to adapt to the specific conditions of their microenvironment. By better understanding their metabolic phenotype and external environmental conditions that support their survival, treatment interventions can be designed to extend current therapy regimens to eradicate TICs. - Highlights: • Ovarian cancer TICs exhibit a decreased glucose and fatty acid oxidation. • TICs are more glycolytic and have highly active mitochondria. • TICs are more resistant to AICAR but not metformin. • A flexible metabolism allows TICs to adapt to their microenvironment. • This flexibility requires development of specific drugs targeting TIC-specific changes to prevent recurrent TIC outgrowth.

  4. Ovarian tumor-initiating cells display a flexible metabolism

    Anderson, Angela S.; Roberts, Paul C.; Frisard, Madlyn I.; Hulver, Matthew W.; Schmelz, Eva M.

    2014-01-01

    An altered metabolism during ovarian cancer progression allows for increased macromolecular synthesis and unrestrained growth. However, the metabolic phenotype of cancer stem or tumor-initiating cells, small tumor cell populations that are able to recapitulate the original tumor, has not been well characterized. In the present study, we compared the metabolic phenotype of the stem cell enriched cell variant, MOSE-L FFLv (TIC), derived from mouse ovarian surface epithelial (MOSE) cells, to their parental (MOSE-L) and benign precursor (MOSE-E) cells. TICs exhibit a decrease in glucose and fatty acid oxidation with a concomitant increase in lactate secretion. In contrast to MOSE-L cells, TICs can increase their rate of glycolysis to overcome the inhibition of ATP synthase by oligomycin and can increase their oxygen consumption rate to maintain proton motive force when uncoupled, similar to the benign MOSE-E cells. TICs have an increased survival rate under limiting conditions as well as an increased survival rate when treated with AICAR, but exhibit a higher sensitivity to metformin than MOSE-E and MOSE-L cells. Together, our data show that TICs have a distinct metabolic profile that may render them flexible to adapt to the specific conditions of their microenvironment. By better understanding their metabolic phenotype and external environmental conditions that support their survival, treatment interventions can be designed to extend current therapy regimens to eradicate TICs. - Highlights: • Ovarian cancer TICs exhibit a decreased glucose and fatty acid oxidation. • TICs are more glycolytic and have highly active mitochondria. • TICs are more resistant to AICAR but not metformin. • A flexible metabolism allows TICs to adapt to their microenvironment. • This flexibility requires development of specific drugs targeting TIC-specific changes to prevent recurrent TIC outgrowth

  5. Alternative Cell Death Pathways and Cell Metabolism

    Simone Fulda

    2013-01-01

    Full Text Available While necroptosis has for long been viewed as an accidental mode of cell death triggered by physical or chemical damage, it has become clear over the last years that necroptosis can also represent a programmed form of cell death in mammalian cells. Key discoveries in the field of cell death research, including the identification of critical components of the necroptotic machinery, led to a revised concept of cell death signaling programs. Several regulatory check and balances are in place in order to ensure that necroptosis is tightly controlled according to environmental cues and cellular needs. This network of regulatory mechanisms includes metabolic pathways, especially those linked to mitochondrial signaling events. A better understanding of these signal transduction mechanisms will likely contribute to open new avenues to exploit our knowledge on the regulation of necroptosis signaling for therapeutic application in the treatment of human diseases.

  6. Cancer cell metabolism: one hallmark, many faces.

    Cantor, Jason R; Sabatini, David M

    2012-10-01

    Cancer cells must rewire cellular metabolism to satisfy the demands of growth and proliferation. Although many of the metabolic alterations are largely similar to those in normal proliferating cells, they are aberrantly driven in cancer by a combination of genetic lesions and nongenetic factors such as the tumor microenvironment. However, a single model of altered tumor metabolism does not describe the sum of metabolic changes that can support cell growth. Instead, the diversity of such changes within the metabolic program of a cancer cell can dictate by what means proliferative rewiring is driven, and can also impart heterogeneity in the metabolic dependencies of the cell. A better understanding of this heterogeneity may enable the development and optimization of therapeutic strategies that target tumor metabolism.

  7. SHMT2 drives glioma cell survival in ischaemia but imposes a dependence on glycine clearance.

    Kim, Dohoon; Fiske, Brian P; Birsoy, Kivanc; Freinkman, Elizaveta; Kami, Kenjiro; Possemato, Richard L; Chudnovsky, Yakov; Pacold, Michael E; Chen, Walter W; Cantor, Jason R; Shelton, Laura M; Gui, Dan Y; Kwon, Manjae; Ramkissoon, Shakti H; Ligon, Keith L; Kang, Seong Woo; Snuderl, Matija; Vander Heiden, Matthew G; Sabatini, David M

    2015-04-16

    Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumour microenvironment. Here we identify a key role for serine and glycine metabolism in the survival of brain cancer cells within the ischaemic zones of gliomas. In human glioblastoma multiforme, mitochondrial serine hydroxymethyltransferase (SHMT2) and glycine decarboxylase (GLDC) are highly expressed in the pseudopalisading cells that surround necrotic foci. We find that SHMT2 activity limits that of pyruvate kinase (PKM2) and reduces oxygen consumption, eliciting a metabolic state that confers a profound survival advantage to cells in poorly vascularized tumour regions. GLDC inhibition impairs cells with high SHMT2 levels as the excess glycine not metabolized by GLDC can be converted to the toxic molecules aminoacetone and methylglyoxal. Thus, SHMT2 is required for cancer cells to adapt to the tumour environment, but also renders these cells sensitive to glycine cleavage system inhibition.

  8. Lung cells support osteosarcoma cell migration and survival.

    Yu, Shibing; Fourman, Mitchell Stephen; Mahjoub, Adel; Mandell, Jonathan Brendan; Crasto, Jared Anthony; Greco, Nicholas Giuseppe; Weiss, Kurt Richard

    2017-01-25

    Osteosarcoma (OS) is the most common primary bone tumor, with a propensity to metastasize to the lungs. Five-year survival for metastatic OS is below 30%, and has not improved for several decades despite the introduction of multi-agent chemotherapy. Understanding OS cell migration to the lungs requires an evaluation of the lung microenvironment. Here we utilized an in vitro lung cell and OS cell co-culture model to explore the interactions between OS and lung cells, hypothesizing that lung cells would promote OS cell migration and survival. The impact of a novel anti-OS chemotherapy on OS migration and survival in the lung microenvironment was also examined. Three human OS cell lines (SJSA-1, Saos-2, U-2) and two human lung cell lines (HULEC-5a, MRC-5) were cultured according to American Type Culture Collection recommendations. Human lung cell lines were cultured in growth medium for 72 h to create conditioned media. OS proliferation was evaluated in lung co-culture and conditioned media microenvironment, with a murine fibroblast cell line (NIH-3 T3) in fresh growth medium as controls. Migration and invasion were measured using a real-time cell analysis system. Real-time PCR was utilized to probe for Aldehyde Dehydrogenase (ALDH1) expression. Osteosarcoma cells were also transduced with a lentivirus encoding for GFP to permit morphologic analysis with fluorescence microscopy. The anti-OS efficacy of Disulfiram, an ALDH-inhibitor previously shown to inhibit OS cell proliferation and metastasis in vitro, was evaluated in each microenvironment. Lung-cell conditioned medium promoted osteosarcoma cell migration, with a significantly higher attractive effect on all three osteosarcoma cell lines compared to basic growth medium, 10% serum containing medium, and NIH-3 T3 conditioned medium (p cell conditioned medium induced cell morphologic changes, as demonstrated with GFP-labeled cells. OS cells cultured in lung cell conditioned medium had increased alkaline

  9. The Essential Role of Cholesterol Metabolism in the Intracellular Survival of Mycobacterium leprae Is Not Coupled to Central Carbon Metabolism and Energy Production.

    Marques, Maria Angela M; Berrêdo-Pinho, Marcia; Rosa, Thabatta L S A; Pujari, Venugopal; Lemes, Robertha M R; Lery, Leticia M S; Silva, Carlos Adriano M; Guimarães, Ana Carolina R; Atella, Georgia C; Wheat, William H; Brennan, Patrick J; Crick, Dean C; Belisle, John T; Pessolani, Maria Cristina V

    2015-12-01

    Mycobacterium leprae induces the formation of lipid droplets, which are recruited to pathogen-containing phagosomes in infected macrophages and Schwann cells. Cholesterol is among the lipids with increased abundance in M. leprae-infected cells, and intracellular survival relies on cholesterol accumulation. The present study investigated the capacity of M. leprae to acquire and metabolize cholesterol. In silico analyses showed that oxidation of cholesterol to cholest-4-en-3-one (cholestenone), the first step of cholesterol degradation catalyzed by the enzyme 3β-hydroxysteroid dehydrogenase (3β-HSD), is apparently the only portion of the cholesterol catabolic pathway seen in Mycobacterium tuberculosis preserved by M. leprae. Incubation of bacteria with radiolabeled cholesterol confirmed the in silico predictions. Radiorespirometry and lipid analyses performed after incubating M. leprae with [4-(14)C]cholesterol or [26-(14)C]cholesterol showed the inability of this pathogen to metabolize the sterol rings or the side chain of cholesterol as a source of energy and carbon. However, the bacteria avidly incorporated cholesterol and, as expected, converted it to cholestenone both in vitro and in vivo. Our data indicate that M. leprae has lost the capacity to degrade and utilize cholesterol as a nutritional source but retains the enzyme responsible for its oxidation to cholestenone. Thus, the essential role of cholesterol metabolism in the intracellular survival of M. leprae is uncoupled from central carbon metabolism and energy production. Further elucidation of cholesterol metabolism in the host cell during M. leprae infection will establish the mechanism by which this lipid supports M. leprae intracellular survival and will open new avenues for novel leprosy therapies. Our study focused on the obligate intracellular pathogen Mycobacterium leprae and its capacity to metabolize cholesterol. The data make an important contribution for those interested in understanding the

  10. Connecting Mitochondria, Metabolism, and Stem Cell Fate

    Wanet, Anaïs; Arnould, Thierry; Najimi, Mustapha

    2015-01-01

    As sites of cellular respiration and energy production, mitochondria play a central role in cell metabolism. Cell differentiation is associated with an increase in mitochondrial content and activity and with a metabolic shift toward increased oxidative phosphorylation activity. The opposite occurs during reprogramming of somatic cells into induced pluripotent stem cells. Studies have provided evidence of mitochondrial and metabolic changes during the differentiation of both embryonic and somatic (or adult) stem cells (SSCs), such as hematopoietic stem cells, mesenchymal stem cells, and tissue-specific progenitor cells. We thus propose to consider those mitochondrial and metabolic changes as hallmarks of differentiation processes. We review how mitochondrial biogenesis, dynamics, and function are directly involved in embryonic and SSC differentiation and how metabolic and sensing pathways connect mitochondria and metabolism with cell fate and pluripotency. Understanding the basis of the crosstalk between mitochondria and cell fate is of critical importance, given the promising application of stem cells in regenerative medicine. In addition to the development of novel strategies to improve the in vitro lineage-directed differentiation of stem cells, understanding the molecular basis of this interplay could lead to the identification of novel targets to improve the treatment of degenerative diseases. PMID:26134242

  11. Metabolic adaptations of Azospirillum brasilense to oxygen stress by cell-to-cell clumping and flocculation.

    Bible, Amber N; Khalsa-Moyers, Gurusahai K; Mukherjee, Tanmoy; Green, Calvin S; Mishra, Priyanka; Purcell, Alicia; Aksenova, Anastasia; Hurst, Gregory B; Alexandre, Gladys

    2015-12-01

    The ability of bacteria to monitor their metabolism and adjust their behavior accordingly is critical to maintain competitiveness in the environment. The motile microaerophilic bacterium Azospirillum brasilense navigates oxygen gradients by aerotaxis in order to locate low oxygen concentrations that can support metabolism. When cells are exposed to elevated levels of oxygen in their surroundings, motile A. brasilense cells implement an alternative response to aerotaxis and form transient clumps by cell-to-cell interactions. Clumping was suggested to represent a behavior protecting motile cells from transiently elevated levels of aeration. Using the proteomics of wild-type and mutant strains affected in the extent of their clumping abilities, we show that cell-to-cell clumping represents a metabolic scavenging strategy that likely prepares the cells for further metabolic stresses. Analysis of mutants affected in carbon or nitrogen metabolism confirmed this assumption. The metabolic changes experienced as clumping progresses prime cells for flocculation, a morphological and metabolic shift of cells triggered under elevated-aeration conditions and nitrogen limitation. The analysis of various mutants during clumping and flocculation characterized an ordered set of changes in cell envelope properties accompanying the metabolic changes. These data also identify clumping and early flocculation to be behaviors compatible with the expression of nitrogen fixation genes, despite the elevated-aeration conditions. Cell-to-cell clumping may thus license diazotrophy to microaerophilic A. brasilense cells under elevated oxygen conditions and prime them for long-term survival via flocculation if metabolic stress persists. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. Increasing Winter Maximal Metabolic Rate Improves Intrawinter Survival in Small Birds.

    Petit, Magali; Clavijo-Baquet, Sabrina; Vézina, François

    Small resident bird species living at northern latitudes increase their metabolism in winter, and this is widely assumed to improve their chances of survival. However, the relationship between winter metabolic performance and survival has yet to be demonstrated. Using capture-mark-recapture, we followed a population of free-living black-capped chickadees (Poecile atricapillus) over 3 yr and evaluated their survival probability within and among winters. We also measured the size-independent body mass (M s ), hematocrit (Hct), basal metabolic rate (BMR), and maximal thermogenic capacity (Msum) and investigated how these parameters influenced survival within and among winters. Results showed that survival probability was high and constant both within (0.92) and among (0.96) winters. They also showed that while M s , Hct, and BMR had no significant influence, survival was positively related to Msum-following a sigmoid relationship-within but not among winter. Birds expressing an Msum below 1.26 W (i.e., similar to summer levels) had a winter. Our data therefore suggest that black-capped chickadees that are either too slow or unable to adjust their phenotype from summer to winter have little chances of survival and thus that seasonal upregulation of metabolic performance is highly beneficial. This study is the first to document in an avian system the relationship between thermogenic capacity and winter survival, a proxy of fitness.

  13. Influence of the Tumor Microenvironment on Cancer Cells Metabolic Reprogramming

    Victoire Gouirand

    2018-04-01

    Full Text Available As with castles, tumor cells are fortified by surrounding non-malignant cells, such as cancer-associated fibroblasts, immune cells, but also nerve fibers and extracellular matrix. In most cancers, this fortification creates a considerable solid pressure which limits oxygen and nutrient delivery to the tumor cells and causes a hypoxic and nutritional stress. Consequently, tumor cells have to adapt their metabolism to survive and proliferate in this harsh microenvironment. To satisfy their need in energy and biomass, tumor cells develop new capacities to benefit from metabolites of the microenvironment, either by their uptake through the macropinocytosis process or through metabolite transporters, or by a cross-talk with stromal cells and capture of extracellular vesicles that are released by the neighboring cells. However, the microenvironments of primary tumor and metastatic niches differ tremendously in their cellular/acellular components and available nutrients. Therefore, cancer cells must develop a metabolic flexibility conferring on them the ability to satisfy their biomass and energetic demands at both primary and metastasis sites. In this review, we propose a brief overview of how proliferating cancer cells take advantage of their surrounding microenvironment to satisfy their high metabolic demand at both primary and metastasis sites.

  14. NAD(P)H-dependent quinone oxidoreductase 1 (NQO1) and cytochrome P450 oxidoreductase (CYP450OR) differentially regulate menadione-mediated alterations in redox status, survival and metabolism in pancreatic β-cells.

    Gray, Joshua P; Karandrea, Shpetim; Burgos, Delaine Zayasbazan; Jaiswal, Anil A; Heart, Emma A

    2016-11-16

    NQO1 (NAD(P)H-quinone oxidoreductase 1) reduces quinones and xenobiotics to less-reactive compounds via 2-electron reduction, one feature responsible for the role of NQO1 in antioxidant defense in several tissues. In contrast, NADPH cytochrome P450 oxidoreductase (CYP450OR), catalyzes the 1-electron reduction of quinones and xenobiotics, resulting in enhanced superoxide formation. However, to date, the roles of NQO1 and CYP450OR in pancreatic β-cell metabolism under basal conditions and oxidant challenge have not been characterized. Using NQO1 inhibition, over-expression and knock out, we have demonstrated that, in addition to protection of β-cells from toxic concentrations of the redox cycling quinone menadione, NQO1 also regulates the basal level of reduced-to-oxidized nucleotides, suggesting other role(s) beside that of an antioxidant enzyme. In contrast, over-expression of NADPH cytochrome P450 oxidoreductase (CYP450OR) resulted in enhanced redox cycling activity and decreased cellular viability, consistent with the enhanced generation of superoxide and H 2 O 2 . Basal expression of NQO1 and CYP450OR was comparable in isolated islets and liver. However, NQO1, but not CYP450OR, was strongly induced in β-cells exposed to menadione. NQO1 and CYP450OR exhibited a reciprocal preference for reducing equivalents in β-cells: while CYP450OR preferentially utilized NADPH, NQO1 primarily utilized NADH. Together, these results demonstrate that NQO1 and CYP450OR reciprocally regulate oxidant metabolism in pancreatic β-cells. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Natural Compounds as Regulators of the Cancer Cell Metabolism

    Claudia Cerella

    2013-01-01

    Full Text Available Even though altered metabolism is an “old” physiological mechanism, only recently its targeting became a therapeutically interesting strategy and by now it is considered an emerging hallmark of cancer. Nevertheless, a very poor number of compounds are under investigation as potential modulators of cell metabolism. Candidate agents should display selectivity of action towards cancer cells without side effects. This ideal favorable profile would perfectly overlap the requisites of new anticancer therapies and chemopreventive strategies as well. Nature represents a still largely unexplored source of bioactive molecules with a therapeutic potential. Many of these compounds have already been characterized for their multiple anticancer activities. Many of them are absorbed with the diet and therefore possess a known profile in terms of tolerability and bioavailability compared to newly synthetized chemical compounds. The discovery of important cross-talks between mediators of the most therapeutically targeted aberrancies in cancer (i.e., cell proliferation, survival, and migration and the metabolic machinery allows to predict the possibility that many anticancer activities ascribed to a number of natural compounds may be due, in part, to their ability of modulating metabolic pathways. In this review, we attempt an overview of what is currently known about the potential of natural compounds as modulators of cancer cell metabolism.

  16. Cell survival and radiation induced chromosome aberrations. Pt. 2

    Bauchinger, M.; Schmid, E.; Braselmann, H.

    1986-01-01

    Human peripheral lymphocytes were irradiated in whole blood with 0.5-4.0 Gy of 220 kVp X-rays and the frequency of chromosome aberrations was determined in 1st or 2nd division metaphases discriminated by fluorescence plus giemsa staining. Using the empirical distributions of aberrations among cells, cell survival and transmission of aberrations were investigated. Considering both daughter cells, we found that 20% of fragments and 55% of dicentrics or ring chromosomes are lost during the 1st cell division; i.e. cell survival rate from 1st to 2nd generation is mainly influenced by anaphase bridging of these two-hit aberrations. Cell survival to 2nd mitosis was calculated considering this situation and compared with the survival derived from the fraction of M1 cells without unstable aberrations. The resulting shouldered survival curves showed significantly different slopes, indicating that cell reproductive death is overestimated in the latter approach. (orig.)

  17. Modification of bacterial cell survival by postirradiation hypoxia

    Vexler, F B; Eidus, L Kh

    1986-01-27

    It is shown that postirradiation hypoxia affects the survival of E.coli. Hypoxic conditions immediately after a single-dose irradiation diminish cell survival in nutrient medium. Increasing time intervals between irradiation and hypoxia decrease the efficiency of the latter, while 1 h after irradiation hypoxia does not modify the survival of irradiated cells. These findings reveal that the mechanisms of action of postirradiation hypoxia on eu- and prokaryotic cells are similar.

  18. B-Cell Metabolic Remodeling and Cancer

    Franchina, Davide G.; Grusdat, Melanie; Brenner, Dirk

    2018-01-01

    Cells of the immune system display varying metabolic profiles to fulfill their functions. B lymphocytes overcome fluctuating energy challenges as they transition from the resting state and recirculation to activation, rapid proliferation, and massive antibody production. Only through a controlled...

  19. Long-term survival in small-cell lung cancer

    Lassen, U; Osterlind, K; Hansen, M

    1995-01-01

    PURPOSE: To describe in patients with small-cell lung cancer (SCLC) the characteristics of those who survive for > or = 5 years, to identify long-term prognostic factors, to analyze survival data of 5-year survivors, and to study 10-year survival in patients entered before 1981. PATIENTS......, especially tobacco-related cancers and other tobacco-related diseases....

  20. Repair models of cell survival and corresponding computer program for survival curve fitting

    Shen Xun; Hu Yiwei

    1992-01-01

    Some basic concepts and formulations of two repair models of survival, the incomplete repair (IR) model and the lethal-potentially lethal (LPL) model, are introduced. An IBM-PC computer program for survival curve fitting with these models was developed and applied to fit the survivals of human melanoma cells HX118 irradiated at different dose rates. Comparison was made between the repair models and two non-repair models, the multitar get-single hit model and the linear-quadratic model, in the fitting and analysis of the survival-dose curves. It was shown that either IR model or LPL model can fit a set of survival curves of different dose rates with same parameters and provide information on the repair capacity of cells. These two mathematical models could be very useful in quantitative study on the radiosensitivity and repair capacity of cells

  1. Glutathione Primes T Cell Metabolism for Inflammation

    Mak, Tak W.; Grusdat, Melanie; Duncan, Gordon S.

    2017-01-01

    the activation of mammalian target of rapamycin-1 (mTOR) and expression of NFAT and Myc transcription factors, abrogating the energy utilization and Myc-dependent metabolic reprogramming that allows activated T cells to switch to glycolysis and glutaminolysis. In vivo, T-cell-specific ablation of murine Gclc...

  2. Actionable Metabolic Pathways in Heart Failure and Cancer—Lessons From Cancer Cell Metabolism

    Anja Karlstaedt

    2018-06-01

    Full Text Available Recent advances in cancer cell metabolism provide unprecedented opportunities for a new understanding of heart metabolism and may offer new approaches for the treatment of heart failure. Key questions driving the cancer field to understand how tumor cells reprogram metabolism and to benefit tumorigenesis are also applicable to the heart. Recent experimental and conceptual advances in cancer cell metabolism provide the cardiovascular field with the unique opportunity to target metabolism. This review compares cancer cell metabolism and cardiac metabolism with an emphasis on strategies of cellular adaptation, and how to exploit metabolic changes for therapeutic benefit.

  3. Integrative Analysis of PRKAG2 Cardiomyopathy iPS and Microtissue Models Identifies AMPK as a Regulator of Metabolism, Survival, and Fibrosis

    J. Travis Hinson

    2016-12-01

    Full Text Available AMP-activated protein kinase (AMPK is a metabolic enzyme that can be activated by nutrient stress or genetic mutations. Missense mutations in the regulatory subunit, PRKAG2, activate AMPK and cause left ventricular hypertrophy, glycogen accumulation, and ventricular pre-excitation. Using human iPS cell models combined with three-dimensional cardiac microtissues, we show that activating PRKAG2 mutations increase microtissue twitch force by enhancing myocyte survival. Integrating RNA sequencing with metabolomics, PRKAG2 mutations that activate AMPK remodeled global metabolism by regulating RNA transcripts to favor glycogen storage and oxidative metabolism instead of glycolysis. As in patients with PRKAG2 cardiomyopathy, iPS cell and mouse models are protected from cardiac fibrosis, and we define a crosstalk between AMPK and post-transcriptional regulation of TGFβ isoform signaling that has implications in fibrotic forms of cardiomyopathy. Our results establish critical connections among metabolic sensing, myocyte survival, and TGFβ signaling.

  4. A track-event theory of cell survival

    Besserer, Juergen; Schneider, Uwe

    2015-01-01

    When fractionation schemes for hypofractionation and stereotactic body radiotherapy are considered, a reliable cell survival model at high dose is needed for calculating doses of similar biological effectiveness. In this work a simple model for cell survival which is valid also at high dose is developed from Poisson statistics. An event is defined by two double strand breaks (DSB) on the same or different chromosomes. An event is always lethal due to direct lethal damage or lethal binary misrepair by the formation of chromosome aberrations. Two different mechanisms can produce events: one-track events (OTE) or two-track-events (TTE). The target for an OTE is always a lethal event, the target for an TTE is one DSB. At least two TTEs on the same or different chromosomes are necessary to produce an event. Both, the OTE and the TTE are statistically independent. From the stochastic nature of cell kill which is described by the Poisson distribution the cell survival probability was derived. It was shown that a solution based on Poisson statistics exists for cell survival. It exhibits exponential cell survival at high dose and a finite gradient of cell survival at vanishing dose, which is in agreement with experimental cell studies. The model fits the experimental data nearly as well as the three-parameter formula of Hug-Kellerer and is only based on two free parameters. It is shown that the LQ formalism is an approximation of the model derived in this work. It could be also shown that the derived model predicts a fractionated cell survival experiment better than the LQ-model. It was shown that cell survival can be described with a simple analytical formula on the basis of Poisson statistics. This solution represents in the limit of large dose the typical exponential behavior and predicts cell survival after fractionated dose application better than the LQ-model.

  5. A track-event theory of cell survival

    Besserer, Juergen; Schneider, Uwe [Zuerich Univ. (Switzerland). Inst. of Physics; Radiotherapy Hirslanden, Zuerich (Switzerland)

    2015-09-01

    When fractionation schemes for hypofractionation and stereotactic body radiotherapy are considered, a reliable cell survival model at high dose is needed for calculating doses of similar biological effectiveness. In this work a simple model for cell survival which is valid also at high dose is developed from Poisson statistics. An event is defined by two double strand breaks (DSB) on the same or different chromosomes. An event is always lethal due to direct lethal damage or lethal binary misrepair by the formation of chromosome aberrations. Two different mechanisms can produce events: one-track events (OTE) or two-track-events (TTE). The target for an OTE is always a lethal event, the target for an TTE is one DSB. At least two TTEs on the same or different chromosomes are necessary to produce an event. Both, the OTE and the TTE are statistically independent. From the stochastic nature of cell kill which is described by the Poisson distribution the cell survival probability was derived. It was shown that a solution based on Poisson statistics exists for cell survival. It exhibits exponential cell survival at high dose and a finite gradient of cell survival at vanishing dose, which is in agreement with experimental cell studies. The model fits the experimental data nearly as well as the three-parameter formula of Hug-Kellerer and is only based on two free parameters. It is shown that the LQ formalism is an approximation of the model derived in this work. It could be also shown that the derived model predicts a fractionated cell survival experiment better than the LQ-model. It was shown that cell survival can be described with a simple analytical formula on the basis of Poisson statistics. This solution represents in the limit of large dose the typical exponential behavior and predicts cell survival after fractionated dose application better than the LQ-model.

  6. Cell signalling and phospholipid metabolism

    Boss, W.F.

    1990-01-01

    These studies explored whether phosphoinositide (PI) has a role in plants analogous to its role in animal cells. Although no parallel activity of PI in signal transduction was found in plant cells, activity of inositol phospholipid kinase was found to be modulated by light and by cell wall degrading enzymes. These studies indicate a major role for inositol phospholipids in plant growth and development as membrane effectors but not as a source of second messengers.

  7. Targeting Metabolic Survival Pathways in Lung Cancer via Combination Therapy

    2014-06-01

    H & Y Enterprise, Redwood City, CA). Following centrifugation at 750 3 g to remove unlysed cells and nuclei, mito - chondria were isolated by...clinically used for diabetes already) or phenformin and glutaminase inhibitors. Several compounds that inhibit GLS are currently under investigation at...Brian P. Fiske,1 Douglas McCloskey,2 Dan Y . Gui,1 Courtney R. Green,2 Natalie I. Vokes,1 Adam M. Feist,2 Matthew G. Vander Heiden,1,3,* and Christian M

  8. Endothelial cell energy metabolism, proliferation, and apoptosis in pulmonary hypertension.

    Xu, Weiling; Erzurum, Serpil C

    2011-01-01

    Pulmonary arterial hypertension (PAH) is a fatal disease characterized by impaired regulation of pulmonary hemodynamics and excessive growth and dysfunction of the endothelial cells that line the arteries in PAH lungs. Establishment of methods for culture of pulmonary artery endothelial cells from PAH lungs has provided the groundwork for mechanistic translational studies that confirm and extend findings from model systems and spontaneous pulmonary hypertension in animals. Endothelial cell hyperproliferation, survival, and alterations of biochemical-metabolic pathways are the unifying endothelial pathobiology of the disease. The hyperproliferative and apoptosis-resistant phenotype of PAH endothelial cells is dependent upon the activation of signal transducer and activator of transcription (STAT) 3, a fundamental regulator of cell survival and angiogenesis. Animal models of PAH, patients with PAH, and human PAH endothelial cells produce low nitric oxide (NO). In association with the low level of NO, endothelial cells have reduced mitochondrial numbers and cellular respiration, which is associated with more than a threefold increase in glycolysis for energy production. The shift to glycolysis is related to low levels of NO and likely to the pathologic expression of the prosurvival and proangiogenic signal transducer, hypoxia-inducible factor (HIF)-1, and the reduced mitochondrial antioxidant manganese superoxide dismutase (MnSOD). In this article, we review the phenotypic changes of the endothelium in PAH and the biochemical mechanisms accounting for the proliferative, glycolytic, and strongly proangiogenic phenotype of these dysfunctional cells, which consequently foster the panvascular progressive pulmonary remodeling in PAH. © 2011 American Physiological Society.

  9. Anti-apoptotic effect of hyperglycemia can allow survival of potentially autoreactive T cells.

    Ramakrishnan, P; Kahn, D A; Baltimore, D

    2011-04-01

    Thymocyte development is a tightly controlled multi-step process involving selective elimination of self-reactive and non-functional T cells by apoptosis. This developmental process depends on signaling by Notch, IL-7 and active glucose metabolism. In this study, we explored the requirement of glucose for thymocyte survival and found that in addition to metabolic regulation, glucose leads to the expression of anti-apoptotic genes. Under hyperglycemic conditions, both mouse and human thymocytes demonstrate enhanced survival. We show that glucose-induced anti-apoptotic genes are dependent on NF-κB p65 because high glucose is unable to attenuate normal ongoing apoptosis of thymocytes isolated from p65 knockout mice. Furthermore, we demonstrate that in vivo hyperglycemia decreases apoptosis of thymocytes allowing for survival of potentially self-reactive thymocytes. These results imply that hyperglycemic conditions could contribute to the development of autoimmunity through dysregulated thymic selection. © 2011 Macmillan Publishers Limited

  10. Helicoverpa armigera (Lepidoptera: Noctuidae) larvae that survive sublethal doses of nucleopolyhedrovirus exhibit high metabolic rates.

    Bouwer, Gustav; Nardini, Luisa; Duncan, Frances D

    2009-04-01

    To determine the effect of sublethal doses of Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (HearSNPV) on the metabolic rate of H. armigera, the respiration rates of third instar H. armigera larvae inoculated with sublethal doses of HearSNPV were evaluated. Respiration rates, measured as the rate of CO(2) production (VCO(2)), were recorded daily using closed-system respirometry. By 4 days post-inoculation (dpi), the metabolic rates of LD(25) or LD(75) survivors were significantly higher than that of uninoculated controls. When dose data were pooled, the VCO(2) values of larvae that survived inoculation (0.0288mlh(-1)), the uninoculated controls (0.0250mlh(-1)), and the larvae that did not survive inoculation (0.0199mlh(-1)) differed significantly from one another. At 4dpi, the VCO(2) of the uninoculated controls were significantly lower than the VCO(2) of inoculation survivors, but significantly higher than the VCO(2) of inoculation non-survivors. Inoculation survivors may have had high metabolic rates due to a combination of viral replication, organ damage, and an energy-intensive induced cellular immune response. The high 4dpi metabolic rate of inoculation survivors may reflect an effective immune response and may be seen as the metabolic signature of larvae that are in the process of surviving inoculation with HearSNPV.

  11. SHMT2 drives glioma cell survival in the tumor microenvironment but imposes a dependence on glycine clearance

    Kim, Dohoon; Fiske, Brian P.; Birsoy, Kivanc; Freinkman, Elizaveta; Kami, Kenjiro; Possemato, Richard; Chudnovsky, Yakov; Pacold, Michael E.; Chen, Walter W.; Cantor, Jason R.; Shelton, Laura M.; Gui, Dan Y.; Kwon, Manjae; Ramkissoon, Shakti H.; Ligon, Keith L.; Kang, Seong Woo; Snuderl, Matija; Heiden, Matthew G. Vander; Sabatini, David M.

    2015-01-01

    SUMMARY Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumor microenvironment1–3. Here, we identify a key role for serine and glycine metabolism in the survival of brain cancer cells within the ischemic zones of gliomas. In human glioblastoma multiforme (GBM), mitochondrial serine hydroxymethyltransferase (SHMT2) and glycine decarboxylase (GLDC) are highly expressed in the pseudopalisading cells that surround necrotic foci. We find that SHMT2 activity limits that of pyruvate kinase (PKM2) and reduces oxygen consumption, eliciting a metabolic state that confers a profound survival advantage to cells in poorly vascularized tumor regions. GLDC inhibition impairs cells with high SHMT2 levels as the excess glycine not metabolized by GLDC can be converted to the toxic molecules aminoacetone and methylglyoxal. Thus, SHMT2 is required for cancer cells to adapt to the tumor environment, but also renders these cells sensitive to glycine cleavage system inhibition. PMID:25855294

  12. Nerve Growth Factor in Cancer Cell Death and Survival

    Molloy, Niamh H.; Read, Danielle E.; Gorman, Adrienne M., E-mail: adrienne.gorman@nuigalway.ie [Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, Galway (Ireland)

    2011-02-01

    One of the major challenges for cancer therapeutics is the resistance of many tumor cells to induction of cell death due to pro-survival signaling in the cancer cells. Here we review the growing literature which shows that neurotrophins contribute to pro-survival signaling in many different types of cancer. In particular, nerve growth factor, the archetypal neurotrophin, has been shown to play a role in tumorigenesis over the past decade. Nerve growth factor mediates its effects through its two cognate receptors, TrkA, a receptor tyrosine kinase and p75{sup NTR}, a member of the death receptor superfamily. Depending on the tumor origin, pro-survival signaling can be mediated by TrkA receptors or by p75{sup NTR}. For example, in breast cancer the aberrant expression of nerve growth factor stimulates proliferative signaling through TrkA and pro-survival signaling through p75{sup NTR}. This latter signaling through p75{sup NTR} promotes increased resistance to the induction of cell death by chemotherapeutic treatments. In contrast, in prostate cells the p75{sup NTR} mediates cell death and prevents metastasis. In prostate cancer, expression of this receptor is lost, which contributes to tumor progression by allowing cells to survive, proliferate and metastasize. This review focuses on our current knowledge of neurotrophin signaling in cancer, with a particular emphasis on nerve growth factor regulation of cell death and survival in cancer.

  13. Nerve Growth Factor in Cancer Cell Death and Survival

    Molloy, Niamh H.; Read, Danielle E.; Gorman, Adrienne M.

    2011-01-01

    One of the major challenges for cancer therapeutics is the resistance of many tumor cells to induction of cell death due to pro-survival signaling in the cancer cells. Here we review the growing literature which shows that neurotrophins contribute to pro-survival signaling in many different types of cancer. In particular, nerve growth factor, the archetypal neurotrophin, has been shown to play a role in tumorigenesis over the past decade. Nerve growth factor mediates its effects through its two cognate receptors, TrkA, a receptor tyrosine kinase and p75 NTR , a member of the death receptor superfamily. Depending on the tumor origin, pro-survival signaling can be mediated by TrkA receptors or by p75 NTR . For example, in breast cancer the aberrant expression of nerve growth factor stimulates proliferative signaling through TrkA and pro-survival signaling through p75 NTR . This latter signaling through p75 NTR promotes increased resistance to the induction of cell death by chemotherapeutic treatments. In contrast, in prostate cells the p75 NTR mediates cell death and prevents metastasis. In prostate cancer, expression of this receptor is lost, which contributes to tumor progression by allowing cells to survive, proliferate and metastasize. This review focuses on our current knowledge of neurotrophin signaling in cancer, with a particular emphasis on nerve growth factor regulation of cell death and survival in cancer

  14. Cellular Glycolysis and The Differential Survival of Lung Fibroblast and Lung Carcinoma Cell Lines.

    Farah, Ibrahim O

    2016-04-01

    Tumor growth and abnormal cell survival were shown to be associated with a number of cellular metabolic abnormalities revealed by impaired oral glucose tolerance, depressed lipoprotein lipase activity leading to hypertriglyceridemia, and changes in amino acid profile as evidenced by increased plasma free tryptophan levels in patients with breast, lung, colon, stomach, and other cancers from various origins. The above findings seem to relate to or indicate a shift to non-oxidative metabolic pathways in cancer. In contrast to normal cells, cancer cells may lose the ability to utilize aerobic respiration due to either defective mitochondria or hypoxia within the tumor microenvironments. Glucose was shown to be the major energy source in cancer cells where it utilizes aerobic /anaerobic glycolysis with the resultant lactic acid formation. The role of energetic modulations and use of glycolytic inhibitors on cancer/normal cell survival is not clearly established in the literature. We hypothesize that natural intermediates of glycolysis and the citric acid cycle will differentially and negatively impact the cancer phenotype in contrast to their no effects on the normal cell phenotype. Therefore, the purpose of this study was to evaluate six potential glycolytic modulators namely, Pyruvic acid, oxalic acid, Zn acetate, sodium citrate, fructose diphosphate (FDP) and sodium bicarbonate at μM concentrations on growing A549 (lung cancer) and MRC-5 (normal; human lung fibroblast) cell lines with the objective of determining their influence on visual impact, cell metabolic activity, cell viability and end-point cell survival. Exposed and non-exposed cells were tested with phase-contrast micro-scanning, survival/death and metabolic activity trends through MTT-assays, as well as death end-point determinations by testing re-growth on complete media and T4 cellometer counts. Results showed that oxalic acid and Zn acetate both influenced the pH of the medium and resulted in

  15. Metabolic characterization of invaded cells of the pancreatic cancer cell line, PANC-1.

    Fujita, Mayumi; Imadome, Kaori; Imai, Takashi

    2017-05-01

    We previously reported that about 0.4% of cells in the cultured human pancreatic cancer cell line, PANC-1, can invade matrigel during the transwell invasion assay, suggesting that these invaded PANC-1 cells may have specific characteristics to keep their invasive potential. To identify the metabolic characterization specific in the invaded PANC-1 cells, metabolome analysis of the invaded PANC-1 compared with the whole cultured PANC-1 was performed using CE-TOFMS, and concentrations of 110 metabolites were measured. In contrast to the whole cultured cells, the invaded PANC-1 was characterized as a population with reduced levels of amino acids and TCA cycle intermediates, and decreased and increased intermediates in glycolysis and nucleic acid metabolism. In particular, the ratio of both adenosine and guanosine energy charge was reduced in the invaded cells, revealing that the consumption of ATP and GTP was high in the invaded cells, and thus suggesting that ATP- or GTP-generating pathways are stimulated. In addition, the GSH/GSSG ratio was low in the invaded cells, but these cells had a higher surviving fraction after exposure to hydrogen peroxide. Thus, the invaded cells were the population resistant to oxidative stress. Furthermore, reduction in intracellular GSH content inhibited PANC-1 invasiveness, indicated that GSH has an important role in PANC-1 invasiveness. Overall, we propose the invaded cells have several unique metabolic profiles. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  16. The bifunctional autophagic flux by 2-deoxyglucose to control survival or growth of prostate cancer cells

    Jeon, Jeong Yong; Kim, Seung Won; Park, Ki Cheong; Yun, Mijin

    2015-01-01

    Recent reports using metabolism regulating drugs showed that nutrient deprivation was an efficient tool to suppress cancer progression. In addition, autophagy control is emerging to prevent cancer cell survival. Autophagy breaks down the unnecessary cytoplasmic components into anabolic units and energy sources, which are the most important sources for making the ATP that maintains homeostasis in cancer cell growth and survival. Therefore, the glucose analog 2-deoxyglucose (2DG) has been used as an anticancer reagent due to its inhibition of glycolysis. Prostate cancer cells (PC3) were treated with 2DG for 6 h or 48 h to analyze the changing of cell cycle and autophagic flux. Rapamycin and LC3B overexpressing vectors were administered to PC3 cells for autophagy induction and chloroquine and shBeclin1 plasmid were used to inhibit autophagy in PC3 cells to analyze PC3 cells growth and survival. The samples for western blotting were prepared in each culture condition to confirm the expression level of autophagy related and regulating proteins. We demonstrated that 2DG inhibits PC3 cells growth and had discriminating effects on autophagy regulation based on the different time period of 2DG treatment to control cell survival. Short-term treatment of 2DG induced autophagic flux, which increased microtubule associated protein 1 light chain 3B (LC3B) conversion rates and reduced p62 levels. However, 2DG induced autophagic flux is remarkably reduced over an extended time period of 2DG treatment for 48 h despite autophagy inducing internal signaling being maintained. The relationship between cell growth and autophagy was proved. Increased autophagic flux by rapamycin or LC3B overexpression powerfully reduced cell growth, while autophagy inhibition with shBeclin1 plasmid or chloroquine had no significant effect on regulating cell growth. Given these results, maintaining increased autophagic flux was more effective at inhibiting cancer cell progression than inhibition of

  17. Cell survival in a simulated Mars environment

    Todd, Paul; Kurk, Michael Andy; Boland, Eugene; Thomas, David

    2016-07-01

    The most ancient life forms on earth date back comfortably to the time when liquid water was believed to be abundant on Mars. These ancient life forms include cyanobacteria, contemporary autotrophic earth organisms believed to have descended from ancestors present as long as 3.5 billion years ago. Contemporary cyanobacteria have adapted to the earth environment's harshest conditions (long-term drying, high and low temperature), and, being autotrophic, they are among the most likely life forms to withstand space travel and the Mars environment. However, it is unlikely that humans would unwittingly contaminate a planetary spacecraft with these microbes. One the other hand, heterotrophic microbes that co-habit with humans are more likely spacecraft contaminants, as history attests. Indeed, soil samples from the Atacama desert have yielded colony-forming organisms resembling enteric bacteria. There is a need to understand the survivability of cyanobacteria (likely survivors, unlikely contaminants) and heterotrophic eubacteria (unlikely survivors, likely contaminants) under simulated planetary conditions. A 35-day test was performed in a commercial planetary simulation system (Techshot, Inc., Greenville, IN) in which the minimum night-time temperature was -80 C, the maximum daytime temperature was +26 C, the simulated day-night light cycle in earth hours was 12-on and 12-off, and the total pressure of the pure CO _{2} atmosphere was maintained below 11 mbar. Any water present was allowed to equilibrate with the changing temperature and pressure. The gas phase was sampled into a CR1-A low-pressure hygrometer (Buck Technologies, Boulder, CO), and dew/frost point was measured once every hour and recorded on a data logger, along with the varying temperature in the chamber, from which the partial pressure of water was calculated. According to measurements there was no liquid water present throughout the test except during the initial pump-down period when aqueous specimens

  18. Techniques for measuring red cell, platelet, and WBC survival

    Mayer, K.; Freeman, J.E.

    1986-01-01

    Blood cell survival studies yield valuable information concerning production and destruction of cells circulating in the bloodstream. Methodologies for the measurement of red cell survival include nonisotopic methods such as differential agglutination and hemolysis. The isotopic label may be radioactive or, if not, will require availability of a mass spectrograph. These methods fall into two categories, one where red cells of all ages are labeled ( 51 Cr, DFP32, etc.) and those employing a cohort label of newly formed cells ( 14 C glycine, 75 Se methionine, etc.). Interpretation of results for methodology employed and mechanism of destruction, random or by senescence, are discussed. A similar approach is presented for platelet and leukocyte survival studies. The inherent difficulties and complications of sequestration, storage, and margination of these cells are emphasized and discussed. 38 references

  19. Stem cell death and survival in heart regeneration and repair.

    Abdelwahid, Eltyeb; Kalvelyte, Audrone; Stulpinas, Aurimas; de Carvalho, Katherine Athayde Teixeira; Guarita-Souza, Luiz Cesar; Foldes, Gabor

    2016-03-01

    Cardiovascular diseases are major causes of mortality and morbidity. Cardiomyocyte apoptosis disrupts cardiac function and leads to cardiac decompensation and terminal heart failure. Delineating the regulatory signaling pathways that orchestrate cell survival in the heart has significant therapeutic implications. Cardiac tissue has limited capacity to regenerate and repair. Stem cell therapy is a successful approach for repairing and regenerating ischemic cardiac tissue; however, transplanted cells display very high death percentage, a problem that affects success of tissue regeneration. Stem cells display multipotency or pluripotency and undergo self-renewal, however these events are negatively influenced by upregulation of cell death machinery that induces the significant decrease in survival and differentiation signals upon cardiovascular injury. While efforts to identify cell types and molecular pathways that promote cardiac tissue regeneration have been productive, studies that focus on blocking the extensive cell death after transplantation are limited. The control of cell death includes multiple networks rather than one crucial pathway, which underlies the challenge of identifying the interaction between various cellular and biochemical components. This review is aimed at exploiting the molecular mechanisms by which stem cells resist death signals to develop into mature and healthy cardiac cells. Specifically, we focus on a number of factors that control death and survival of stem cells upon transplantation and ultimately affect cardiac regeneration. We also discuss potential survival enhancing strategies and how they could be meaningful in the design of targeted therapies that improve cardiac function.

  20. Regulation of glucose metabolism in T cells; new insight into the role of Phosphoinositide 3-kinases

    David K Finlay

    2012-08-01

    Full Text Available Naïve T cells are relatively quiescent cells that only require energy to prevent atrophy and for survival and migration. However, in response to developmental or extrinsic cues T cells can engage in rapid growth and robust proliferation, produce of a range of effector molecules and migrate through peripheral tissues. To meet the significantly increased metabolic demands of these activities, T cells switch from primarily metabolizing glucose to carbon dioxide through oxidative phosphorylation to utilizing glycolysis to convert glucose to lactate (termed aerobic glycolysis. This metabolic switch allows glucose to be used as a source of carbon to generate biosynthetic precursors for the production of protein, DNA and phospholipids, and is crucial for T cells to meet metabolic demands. Phosphoinositide 3-kinases (PI3K are a family of inositol lipid kinases linked with a broad range of cellular functions in T lymphocytes that include cell growth, proliferation, metabolism, differentiation, survival and migration. Initial research described a critical role for PI3K signaling through Akt (also called Protein kinase B for the increased glucose uptake and glycolysis that accompanies T cell activation. This review article relates this original research with more recent data and discusses the evidence for and against a role for PI3K in regulating the metabolic switch to aerobic glycolysis in T cells.

  1. Stem cell aging: Survival of the laziest?

    Muller-Sieburg, Christa; Sieburg, Hans B.

    2008-01-01

    The question whether stem cells age remains an enigma. Traditionally, aging was thought to change the properties of hematopoietic stem cells (HSC). We discuss here a new model of stem cell aging that challenges this view. It is now well-established that the HSC compartment is heterogeneous, consisting of epigenetically fixed subpopulations of HSC that differ in self-renewal and differentiation capacity. New data show that the representation of these HSC subsets changes during aging. HSC that ...

  2. Activation of CHK1 in Supporting Cells Indirectly Promotes Hair Cell Survival

    Azadeh Jadali

    2017-05-01

    Full Text Available The sensory hair cells of the inner ear are exquisitely sensitive to ototoxic insults. Loss of hair cells after exposure to ototoxic agents causes hearing loss. Chemotherapeutic agents such as cisplatin causes hair cell loss. Cisplatin forms DNA mono-adducts as well as intra- and inter-strand DNA crosslinks. DNA cisplatin adducts are repaired through the DNA damage response. The decision between cell survival and cell death following DNA damage rests on factors that are involved in determining damage tolerance, cell survival and apoptosis. Cisplatin damage on hair cells has been the main focus of many ototoxic studies, yet the effect of cisplatin on supporting cells has been largely ignored. In this study, the effects of DNA damage response in cochlear supporting cells were interrogated. Supporting cells play a major role in the development, maintenance and oto-protection of hair cells. Loss of supporting cells may indirectly affect hair cell survival or maintenance. Activation of the Phosphoinositide 3-Kinase (PI3K signaling was previously shown to promote hair cell survival. To test whether activating PI3K signaling promotes supporting cell survival after cisplatin damage, cochlear explants from the neural subset (NS Cre Pten conditional knockout mice were employed. Deletion of Phosphatase and Tensin Homolog (PTEN activates PI3K signaling in multiple cell types within the cochlea. Supporting cells lacking PTEN showed increased cell survival after cisplatin damage. Supporting cells lacking PTEN also showed increased phosphorylation of Checkpoint Kinase 1 (CHK1 levels after cisplatin damage. Nearest neighbor analysis showed increased numbers of supporting cells with activated PI3K signaling in close proximity to surviving hair cells in cisplatin damaged cochleae. We propose that increased PI3K signaling promotes supporting cell survival through phosphorylation of CHK1 and increased survival of supporting cells indirectly increases hair cell

  3. Metabolic profiling reveals potential metabolic markers associated with Hypoxia Inducible Factor-mediated signalling in hypoxic cancer cells.

    Armitage, Emily G; Kotze, Helen L; Allwood, J William; Dunn, Warwick B; Goodacre, Royston; Williams, Kaye J

    2015-10-28

    Hypoxia inducible factors (HIFs) plays an important role in oxygen compromised environments and therefore in tumour survival. In this research, metabolomics has been applied to study HIFs metabolic function in two cell models: mouse hepatocellular carcinoma and human colon carcinoma, whereby the metabolism has been profiled for a range of oxygen potentials. Wild type cells have been compared to cells deficient in HIF signalling to reveal its effect on cellular metabolism under normal oxygen conditions as well as low oxygen, hypoxic and anoxic environments. Characteristic responses to hypoxia that were conserved across both cell models involved the anti-correlation between 2-hydroxyglutarate, 2-oxoglutarate, fructose, hexadecanoic acid, hypotaurine, pyruvate and octadecenoic acid with 4-hydroxyproline, aspartate, cysteine, glutamine, lysine, malate and pyroglutamate. Further to this, network-based correlation analysis revealed HIF specific pathway responses to each oxygen condition that were also conserved between cell models. From this, 4-hydroxyproline was revealed as a regulating hub in low oxygen survival of WT cells while fructose appeared to be in HIF deficient cells. Pathways surrounding these hubs were built from the direct connections of correlated metabolites that look beyond traditional pathways in order to understand the mechanism of HIF response to low oxygen environments.

  4. Surviving the crash: T-cell homeostasis

    TOSHIBA

    The formation of higher order apoptotic structures at the mitochondrion precedes cellular collapse dead. Tracking bax multimerization at mitochondria wildtype. Bax active -6A7. Nucleus – H33342. Apoptotic T-cells ...

  5. Radiation cell survival and growth delay studies in multicellular spheroids of small-cell lung carcinoma

    Duchesne, G.M.; Peacock, J.H.

    1987-01-01

    The radiation sensitivity of two small-cell lung carcinoma cell lines growing as multicellular spheroids in static culture was determined using clonogenic cell survival and growth delay as endpoints. Growth delay determination suggested that clonogenic cell kill was less than was obtained by direct assay of cell survival. Recovery from potentially lethal damage was assayed in one line (HC12) but was not demonstrable, and clonogenic cell survival decreased with time in treated spheroids with diameters greater than 300 μm which contained a hypoxic cell population. Microscopic examination of the treated spheroids showed the emergence of an abnormal giant-cell population, and the progressive clonogenic cell loss that occurred after treatment was thought to be due to oxygen and nutrient deprivation of the remaining viable cells by this doomed cell population. Correction of the growth delay measurements for changes in cell size and clonogenic cell population allowed correlation of the growth delay and cell survival data. (author)

  6. PDHA1 gene knockout in prostate cancer cells results in metabolic reprogramming towards greater glutamine dependence

    Li, Yaqing; Li, Xiaoran; Li, Xiaoli; Zhong, Yali; Ji, Yasai; Yu, Dandan; Zhang, Mingzhi; Wen, Jian-Guo; Zhang, Hongquan; Goscinski, Mariusz Adam; Nesland, Jahn M.; Suo, Zhenhe

    2016-01-01

    Alternative pathways of metabolism endowed cancer cells with metabolic stress. Inhibiting the related compensatory pathways might achieve synergistic anticancer results. This study demonstrated that pyruvate dehydrogenase E1α gene knockout (PDHA1 KO) resulted in alterations in tumor cell metabolism by rendering the cells with increased expression of glutaminase1 (GLS1) and glutamate dehydrogenase1 (GLUD1), leading to an increase in glutamine-dependent cell survival. Deprivation of glutamine induced cell growth inhibition, increased reactive oxygen species and decreased ATP production. Pharmacological blockade of the glutaminolysis pathway resulted in massive tumor cells apoptosis and dysfunction of ROS scavenge in the LNCaP PDHA1 KO cells. Further examination of the key glutaminolysis enzymes in human prostate cancer samples also revealed that higher levels of GLS1 and GLUD1 expression were significantly associated with aggressive clinicopathological features and poor clinical outcome. These insights supply evidence that glutaminolysis plays a compensatory role for cell survival upon alternative energy metabolism and targeting the glutamine anaplerosis of energy metabolism via GLS1 and GLUD1 in cancer cells may offer a potential novel therapeutic strategy. PMID:27462778

  7. Basal metabolic state governs AIF-dependent growth support in pancreatic cancer cells

    Scott, Andrew J.; Wilkinson, Amanda S.; Wilkinson, John C.

    2016-01-01

    Apoptosis-inducing factor (AIF), named for its involvement in cell death pathways, is a mitochondrial protein that regulates metabolic homeostasis. In addition to supporting the survival of healthy cells, AIF also plays a contributory role to the development of cancer through its enzymatic activity, and we have previously shown that AIF preferentially supports advanced-stage prostate cancer cells. Here we further evaluated the role of AIF in tumorigenesis by exploring its function in pancreatic cancer, a disease setting that most often presents at an advanced stage by the time of diagnosis. A bioinformatics approach was first employed to investigate AIF mRNA transcript levels in pancreatic tumor specimens vs. normal tissues. AIF-deficient pancreatic cancer cell lines were then established via lentiviral infection. Immunoblot analysis was used to determine relative protein quantities within cells. Cell viability was measured by flow cytometry; in vitro and Matrigel™ growth/survival using Coulter™ counting and phase contrast microscopy; and glucose consumption in the absence and presence of Matrigel™ using spectrophotometric methods. Archival gene expression data revealed a modest elevation of AIF transcript levels in subsets of pancreatic tumor specimens, suggesting a possible role in disease progression. AIF expression was then suppressed in a panel of five pancreatic cancer cell lines that display diverse metabolic phenotypes. AIF ablation selectively crippled the growth of cells in vitro in a manner that directly correlated with the loss of mitochondrial respiratory chain subunits and altered glucose metabolism, and these effects were exacerbated in the presence of Matrigel™ substrate. This suggests a critical metabolic role for AIF to pancreatic tumorigenesis, while the spectrum of sensitivities to AIF ablation depends on basal cellular metabolic phenotypes. Altogether these data indicate that AIF supports the growth and survival of metabolically defined

  8. Potential effects of the invasive species Gracilaria vermiculophylla on Zostera marina metabolism and survival.

    Martínez-Lüscher, Johann; Holmer, Marianne

    2010-06-01

    The potential threat to seagrasses of the invasive algae, Gracilaria vermiculophylla was assessed through metabolic indicators under experimental conditions. Net leaf photosynthesis (LNP) and dark respiration (LDR) were measured from leaf segments of Zostera marina shoots under different loads of G. vermiculophylla (control, low 2.2kg FW m(-2) and high 4kg FW m(-2)) in mesocosm experiments separated in tanks at four temperatures (19, 23.5, 26 and 30 degrees C). LNP decreased in the presence of the high density G. vermiculophylla mat (25% on average), being the most severe reductions at 30 degrees C (35% less in high). LDR did not respond significantly to differences in algal biomass, whereas a progressive increase was found with increasing temperatures (3.4 times higher at 30 degrees C than at 19 degrees C). Sulphide in porewater was measured weekly in order clarify the role of sediment conditions on seagrass metabolism, and increased both with algal biomass (29% in high) and temperature (from 0.5mM at 26 degrees C to 2.6mM at 30 degrees C), but changes in LNP and LDR were not correlated with sulphide concentrations. Seagrass survival rates showed decreasing trend with algal biomass at all the temperatures (from 74% to 21% survival). G. vermiculophylla showed harmful effects on Z. marina metabolism and survival with synergistic effects of temperature suggesting greater impact of invasive species under future higher water temperatures.

  9. Hematopoietic stem cell fate through metabolic control.

    Ito, Kyoko; Ito, Keisuke

    2018-05-25

    Hematopoietic stem cells (HSCs) maintain a quiescent state in the bone marrow to preserve their self-renewal capacity, but also undergo cell divisions as required. Organelles such as the mitochondria sustain cumulative damage during these cell divisions, and this damage may eventually compromise the cells' self-renewal capacity. HSC divisions result in either self-renewal or differentiation, with the balance between the two directly impacting hematopoietic homeostasis; but the heterogeneity of available HSC-enriched fractions, together with the technical challenges of observing HSC behavior, has long hindered the analysis of individual HSCs, and prevented the elucidation of this process. However, recent advances in genetic models, metabolomics analyses and single-cell approaches have revealed the contributions made to HSC self-renewal by metabolic cues, mitochondrial biogenesis, and autophagy/mitophagy, which have highlighted mitochondrial quality as a key control factor in the equilibrium of HSCs. A deeper understanding of precisely how specific modes of metabolism control HSC fate at the single cell level is therefore not only of great biological interest, but will have clear clinical implications for the development of therapies for hematological disease. Copyright © 2018. Published by Elsevier Inc.

  10. Repair-misrepair model of cell survival

    Tobias, C.A.; Blakely, E.A.; Ngo, F.Q.H.

    1980-01-01

    During the last three years a new model, the repair-misrepair model (RMR) has been proposed, to interpret radiobiological experiments with heavy ions. In using the RMR model it became apparent that some of its features are suitable for handling the effects produced by a variety of environmental agents in addition to ionizing radiation. Two separate sequences of events are assumed to take place in an irradiated cell. The first sequence begins with an initial energy transfer consisting of ionizations and excitations, culminating via fast secondary physical and chemical processes in established macromolecular lesions in essential cell structures. The second sequence contains the responses of the cell to the lesions and consists of the processes of recognition and molecular repair. In normal cells there exists one repair process or at most a few enzymatic repair processes for each essential macromolecular lesion. The enzymatic repair processes may last for hours and minutes, and can be separated in time from the initial physicochemical and later genetic phases

  11. Metabolic cooperation between cancer and non-cancerous stromal cells is pivotal in cancer progression.

    Lopes-Coelho, Filipa; Gouveia-Fernandes, Sofia; Serpa, Jacinta

    2018-02-01

    The way cancer cells adapt to microenvironment is crucial for the success of carcinogenesis, and metabolic fitness is essential for a cancer cell to survive and proliferate in a certain organ/tissue. The metabolic remodeling in a tumor niche is endured not only by cancer cells but also by non-cancerous cells that share the same microenvironment. For this reason, tumor cells and stromal cells constitute a complex network of signal and organic compound transfer that supports cellular viability and proliferation. The intensive dual-address cooperation of all components of a tumor sustains disease progression and metastasis. Herein, we will detail the role of cancer-associated fibroblasts, cancer-associated adipocytes, and inflammatory cells, mainly monocytes/macrophages (tumor-associated macrophages), in the remodeling and metabolic adaptation of tumors.

  12. VEGF improves survival of mesenchymal stem cells in infarcted hearts

    Pons, Jennifer; Huang Yu; Arakawa-Hoyt, Janice; Washko, Daniel; Takagawa, Junya; Ye, Jianqin; Grossman, William; Su Hua

    2008-01-01

    Bone marrow-derived mesenchymal stem cells (MSC) are a promising source for cell-based treatment of myocardial infarction (MI), but existing strategies are restricted by low cell survival and engraftment. We examined whether vascular endothelial growth factor (VEGF) improve MSC viability in infracted hearts. We found long-term culture increased MSC-cellular stress: expressing more cell cycle inhibitors, p16 INK , p21 and p19 ARF . VEGF treatment reduced cellular stress, increased pro-survival factors, phosphorylated-Akt and Bcl-xL expression and cell proliferation. Co-injection of MSCs with VEGF to MI hearts increased cell engraftment and resulted in better improvement of cardiac function than that injected with MSCs or VEGF alone. In conclusion, VEGF protects MSCs from culture-induce cellular stress and improves their viability in ischemic myocardium, which results in improvements of their therapeutic effect for the treatment of MI

  13. Pyruvate Kinase Triggers a Metabolic Feedback Loop that Controls Redox Metabolism in Respiring Cells

    Grüning, N.M.; Rinnerthaler, M.; Bluemlein, K.; Mulleder, M.; Wamelink, M.M.C.; Lehrach, H.; Jakobs, C.A.J.M.; Breitenbach, M.; Ralser, M.

    2011-01-01

    In proliferating cells, a transition from aerobic to anaerobic metabolism is known as the Warburg effect, whose reversal inhibits cancer cell proliferation. Studying its regulator pyruvate kinase (PYK) in yeast, we discovered that central metabolism is self-adapting to synchronize redox metabolism

  14. Metabolic features of the cell danger response.

    Naviaux, Robert K

    2014-05-01

    The cell danger response (CDR) is the evolutionarily conserved metabolic response that protects cells and hosts from harm. It is triggered by encounters with chemical, physical, or biological threats that exceed the cellular capacity for homeostasis. The resulting metabolic mismatch between available resources and functional capacity produces a cascade of changes in cellular electron flow, oxygen consumption, redox, membrane fluidity, lipid dynamics, bioenergetics, carbon and sulfur resource allocation, protein folding and aggregation, vitamin availability, metal homeostasis, indole, pterin, 1-carbon and polyamine metabolism, and polymer formation. The first wave of danger signals consists of the release of metabolic intermediates like ATP and ADP, Krebs cycle intermediates, oxygen, and reactive oxygen species (ROS), and is sustained by purinergic signaling. After the danger has been eliminated or neutralized, a choreographed sequence of anti-inflammatory and regenerative pathways is activated to reverse the CDR and to heal. When the CDR persists abnormally, whole body metabolism and the gut microbiome are disturbed, the collective performance of multiple organ systems is impaired, behavior is changed, and chronic disease results. Metabolic memory of past stress encounters is stored in the form of altered mitochondrial and cellular macromolecule content, resulting in an increase in functional reserve capacity through a process known as mitocellular hormesis. The systemic form of the CDR, and its magnified form, the purinergic life-threat response (PLTR), are under direct control by ancient pathways in the brain that are ultimately coordinated by centers in the brainstem. Chemosensory integration of whole body metabolism occurs in the brainstem and is a prerequisite for normal brain, motor, vestibular, sensory, social, and speech development. An understanding of the CDR permits us to reframe old concepts of pathogenesis for a broad array of chronic, developmental

  15. Pyridine nucleotides in regulation of cell death and survival by redox and non-redox reactions.

    Novak Kujundžić, Renata; Žarković, Neven; Gall Trošelj, Koraljka

    2014-01-01

    Changes of the level and ratios of pyridine nucleotides determine metabolism- dependent cellular redox status and the activity of poly(ADP-ribose) polymerases (PARPs) and sirtuins, thereby influencing several processes closely related to cell survival and death. Pyridine nucleotides participate in numerous metabolic reactions whereby their net cellular level remains constant, but the ratios of NAD+/NADP+ and NADH/NADPH oscillate according to metabolic changes in response to diverse stress signals. In non-redox reactions, NAD+ is degraded and quickly, afterward, resynthesized in the NAD+ salvage pathway, unless overwhelming activation of PARP-1 consumes NAD+ to the point of no return, when the cell can no longer generate enough ATP to accommodate NAD+ resynthesis. The activity of PARP-1 is mandatory for the onset of cytoprotective autophagy on sublethal stress signals. It has become increasingly clear that redox status, largely influenced by the metabolism-dependent composition of the pyridine nucleotides pool, plays an important role in the synthesis of pro-apoptotic and anti-apoptotic sphingolipids. Awareness of the involvement of the prosurvival sphingolipid, sphingosine-1-phosphate, in transition from inflammation to malignant transformation has recently emerged. Here, the participation of pyridine nucleotides in redox and non-redox reactions, sphingolipid metabolism, and their role in cell fate decisions is reviewed.

  16. Various Wolbachia genotypes differently influence host Drosophila dopamine metabolism and survival under heat stress conditions.

    Gruntenko, Nataly Е; Ilinsky, Yury Yu; Adonyeva, Natalya V; Burdina, Elena V; Bykov, Roman A; Menshanov, Petr N; Rauschenbach, Inga Yu

    2017-12-28

    One of the most widespread prokaryotic symbionts of invertebrates is the intracellular bacteria of Wolbachia genus which can be found in about 50% of insect species. Wolbachia causes both parasitic and mutualistic effects on its host that include manipulating the host reproductive systems in order to increase their transmission through the female germline, and increasing the host fitness. One of the mechanisms, promoting adaptation in biological organisms, is a non-specific neuroendocrine stress reaction. In insects, this reaction includes catecholamines, dopamine, serotonin and octopamine, which act as neurotransmitters, neuromodulators and neurohormones. The level of dopamine metabolism correlates with heat stress resistance in Drosophila adults. To examine Wolbachia effect on Drosophila survival under heat stress and dopamine metabolism we used five strains carrying the nuclear background of interbred Bi90 strain and cytoplasmic backgrounds with different genotype variants of Wolbachia (produced by 20 backcrosses of Bi90 males with appropriate source of Wolbachia). Non-infected Bi90 strain (treated with tetracycline for 3 generations) was used as a control group. We demonstrated that two of five investigated Wolbachia variants promote changes in Drosophila heat stress resistance and activity of enzymes that produce and degrade dopamine, alkaline phosphatase and dopamine-dependent arylalkylamine N-acetyltransferase. What is especially interesting, wMelCS genotype of Wolbachia increases stress resistance and the intensity of dopamine metabolism, whereas wMelPop strain decreases them. wMel, wMel2 and wMel4 genotypes of Wolbachia do not show any effect on the survival under heat stress or dopamine metabolism. L-DOPA treatment, known to increase the dopamine content in Drosophila, levels the difference in survival under heat stress between all studied groups. The genotype of symbiont determines the effect that the symbiont has on the stress resistance of the host

  17. Veratridine increases the survival of retinal ganglion cells in vitro

    S.P.F. Pereira

    1997-12-01

    Full Text Available Neuronal cell death is an important phenomenon involving many biochemical pathways. This degenerative event has been studied to understand how the cells activate the mechanisms that lead to self-destruction. Target cells and afferent cells play a relevant role in the regulation of natural cell death. We studied the effect of veratridine (1.5, 3.0, 4.5 and 6.0 µM on the survival of neonatal rat retinal ganglion cells in vitro. Veratridine (3.0 µM, a well-known depolarizing agent that opens the Na+ channel, promoted a two-fold increase in the survival of retinal ganglion cells kept in culture for 48 h. This effect was dose-dependent and was blocked by 1.0 µM tetrodotoxin (a classical voltage-dependent Na+ channel blocker and 30.0 µM flunarizine (a Na+ and Ca2+ channel blocker. These results indicate that electrical activity is also important for the maintenance of retinal ganglion cell survival in vitro

  18. Notch controls the survival of memory CD4+ T cells by regulating glucose uptake.

    Maekawa, Yoichi; Ishifune, Chieko; Tsukumo, Shin-ichi; Hozumi, Katsuto; Yagita, Hideo; Yasutomo, Koji

    2015-01-01

    CD4+ T cells differentiate into memory T cells that protect the host from subsequent infection. In contrast, autoreactive memory CD4+ T cells harm the body by persisting in the tissues. The underlying pathways controlling the maintenance of memory CD4+ T cells remain undefined. We show here that memory CD4+ T cell survival is impaired in the absence of the Notch signaling protein known as recombination signal binding protein for immunoglobulin κ J region (Rbpj). Treatment of mice with a Notch inhibitor reduced memory CD4+ T cell numbers and prevented the recurrent induction of experimental autoimmune encephalomyelitis. Rbpj-deficient CD4+ memory T cells exhibit reduced glucose uptake due to impaired AKT phosphorylation, resulting in low Glut1 expression. Treating mice with pyruvic acid, which bypasses glucose uptake and supplies the metabolite downstream of glucose uptake, inhibited the decrease of autoimmune memory CD4+ T cells in the absence of Notch signaling, suggesting memory CD4+ T cell survival relies on glucose metabolism. Together, these data define a central role for Notch signaling in maintaining memory CD4+ T cells through the regulation of glucose uptake.

  19. Survival of added bacterial species and metabolism of toxic compounds in natural environments

    King, V.M.

    1987-01-01

    Bacteria able to degrade either 2,4-dichlorophenol (DCP) or phenanthrene (PHEN) were isolated from polluted freshwater environments. Two isolates able to degrade each compound were tested for mineralization with a sensitive 14 C assay and for survival in lake water and sewage using a selective medium. One DCP isolate was identified as Alcaligenes paradoxus and the other as Alcaligenes sp. One PHEN isolate was identified as Pseudomonas fluorescens and the other as Pseudomonas sp. All four isolates survived and grew in sterile environments which indicated that starvation would not be a factor in survival of these strains. The number of organisms declined immediately in number in nonsterile lake water. However, they did survive or even grow in nonsterile sewage for a short period before declining in number. Biotic factors appeared to be influential for survival and mineralization of target compounds in many environments. The removal of protozoa, which prey on bacteria, improved survival of the added cells, but had no influence on the mineralization of 10 μg DCP/L. In comparison, degradation of 10 and 25 mg DCP/L stopped after a few days. Yeast nitrogen base appeared to overcome the lack of nutrient regeneration, a function attributed to protozoa. The additional nutrients increased toxicant mineralization, especially when seeded with appropriate species. Thus, protozoa may limit growth of added cells but appear to be needed for mineralization of higher concentrations of DCP

  20. Synthetic dosage lethality in the human metabolic network is highly predictive of tumor growth and cancer patient survival.

    Megchelenbrink, Wout; Katzir, Rotem; Lu, Xiaowen; Ruppin, Eytan; Notebaart, Richard A

    2015-09-29

    Synthetic dosage lethality (SDL) denotes a genetic interaction between two genes whereby the underexpression of gene A combined with the overexpression of gene B is lethal. SDLs offer a promising way to kill cancer cells by inhibiting the activity of SDL partners of activated oncogenes in tumors, which are often difficult to target directly. As experimental genome-wide SDL screens are still scarce, here we introduce a network-level computational modeling framework that quantitatively predicts human SDLs in metabolism. For each enzyme pair (A, B) we systematically knock out the flux through A combined with a stepwise flux increase through B and search for pairs that reduce cellular growth more than when either enzyme is perturbed individually. The predictive signal of the emerging network of 12,000 SDLs is demonstrated in five different ways. (i) It can be successfully used to predict gene essentiality in shRNA cancer cell line screens. Moving to clinical tumors, we show that (ii) SDLs are significantly underrepresented in tumors. Furthermore, breast cancer tumors with SDLs active (iii) have smaller sizes and (iv) result in increased patient survival, indicating that activation of SDLs increases cancer vulnerability. Finally, (v) patient survival improves when multiple SDLs are present, pointing to a cumulative effect. This study lays the basis for quantitative identification of cancer SDLs in a model-based mechanistic manner. The approach presented can be used to identify SDLs in species and cell types in which "omics" data necessary for data-driven identification are missing.

  1. Glycogen synthesis is induced in hypoxia by the hypoxia-inducible factor and promotes cancer cell survival

    Joffrey ePelletier

    2012-02-01

    Full Text Available The hypoxia-inducible factor 1 (HIF-1, in addition to genetic and epigenetic changes, is largely responsible for alterations in cell metabolism in hypoxic tumor cells. This transcription factor not only favors cell proliferation through the metabolic shift from oxidative phosphorylation to glycolysis and lactic acid production but also stimulates nutrient supply by mediating adaptive survival mechanisms. In this study we showed that glycogen synthesis is enhanced in non-cancer and cancer cells when exposed to hypoxia, resulting in a large increase in glycogen stores. Furthermore, we demonstrated that the mRNA and protein levels of the first enzyme of glycogenesis, phosphoglucomutase1 (PGM1, were increased in hypoxia. We showed that induction of glycogen storage as well as PGM1 expression were dependent on HIF-1 and HIF-2. We established that hypoxia-induced glycogen stores are rapidly mobilized in cells that are starved of glucose. Glycogenolysis allows these hypoxia-preconditioned cells to confront and survive glucose deprivation. In contrast normoxic control cells exhibit a high rate of cell death following glucose removal. These findings point to the important role of hypoxia and HIF in inducing mechanisms of rapid adaptation and survival in response to a decrease in oxygen tension. We propose that a decrease in pO2 acts as an alarm that prepares the cells to face subsequent nutrient depletion and to survive.

  2. Glycogen Synthesis is Induced in Hypoxia by the Hypoxia-Inducible Factor and Promotes Cancer Cell Survival

    Pelletier, Joffrey; Bellot, Grégory [Institute of Developmental Biology and Cancer Research, CNRS-UMR 6543, Centre Antoine Lacassagne, University of Nice-Sophia Antipolis, Nice (France); Gounon, Pierre; Lacas-Gervais, Sandra [Centre Commun de Microscopie Appliquée, University of Nice-Sophia Antipolis, Nice (France); Pouysségur, Jacques; Mazure, Nathalie M., E-mail: mazure@unice.fr [Institute of Developmental Biology and Cancer Research, CNRS-UMR 6543, Centre Antoine Lacassagne, University of Nice-Sophia Antipolis, Nice (France)

    2012-02-28

    The hypoxia-inducible factor 1 (HIF-1), in addition to genetic and epigenetic changes, is largely responsible for alterations in cell metabolism in hypoxic tumor cells. This transcription factor not only favors cell proliferation through the metabolic shift from oxidative phosphorylation to glycolysis and lactic acid production but also stimulates nutrient supply by mediating adaptive survival mechanisms. In this study we showed that glycogen synthesis is enhanced in non-cancer and cancer cells when exposed to hypoxia, resulting in a large increase in glycogen stores. Furthermore, we demonstrated that the mRNA and protein levels of the first enzyme of glycogenesis, phosphoglucomutase1 (PGM1), were increased in hypoxia. We showed that induction of glycogen storage as well as PGM1 expression were dependent on HIF-1 and HIF-2. We established that hypoxia-induced glycogen stores are rapidly mobilized in cells that are starved of glucose. Glycogenolysis allows these “hypoxia-preconditioned” cells to confront and survive glucose deprivation. In contrast normoxic control cells exhibit a high rate of cell death following glucose removal. These findings point to the important role of hypoxia and HIF in inducing mechanisms of rapid adaptation and survival in response to a decrease in oxygen tension. We propose that a decrease in pO{sub 2} acts as an “alarm” that prepares the cells to face subsequent nutrient depletion and to survive.

  3. Glycogen Synthesis is Induced in Hypoxia by the Hypoxia-Inducible Factor and Promotes Cancer Cell Survival

    Pelletier, Joffrey; Bellot, Grégory; Gounon, Pierre; Lacas-Gervais, Sandra; Pouysségur, Jacques; Mazure, Nathalie M.

    2012-01-01

    The hypoxia-inducible factor 1 (HIF-1), in addition to genetic and epigenetic changes, is largely responsible for alterations in cell metabolism in hypoxic tumor cells. This transcription factor not only favors cell proliferation through the metabolic shift from oxidative phosphorylation to glycolysis and lactic acid production but also stimulates nutrient supply by mediating adaptive survival mechanisms. In this study we showed that glycogen synthesis is enhanced in non-cancer and cancer cells when exposed to hypoxia, resulting in a large increase in glycogen stores. Furthermore, we demonstrated that the mRNA and protein levels of the first enzyme of glycogenesis, phosphoglucomutase1 (PGM1), were increased in hypoxia. We showed that induction of glycogen storage as well as PGM1 expression were dependent on HIF-1 and HIF-2. We established that hypoxia-induced glycogen stores are rapidly mobilized in cells that are starved of glucose. Glycogenolysis allows these “hypoxia-preconditioned” cells to confront and survive glucose deprivation. In contrast normoxic control cells exhibit a high rate of cell death following glucose removal. These findings point to the important role of hypoxia and HIF in inducing mechanisms of rapid adaptation and survival in response to a decrease in oxygen tension. We propose that a decrease in pO 2 acts as an “alarm” that prepares the cells to face subsequent nutrient depletion and to survive.

  4. p63 promotes cell survival through fatty acid synthase.

    Venkata Sabbisetti

    2009-06-01

    Full Text Available There is increasing evidence that p63, and specifically DeltaNp63, plays a central role in both development and tumorigenesis by promoting epithelial cell survival. However, few studies have addressed the molecular mechanisms through which such important function is exerted. Fatty acid synthase (FASN, a key enzyme that synthesizes long-chain fatty acids and is involved in both embryogenesis and cancer, has been recently proposed as a direct target of p53 family members, including p63 and p73. Here we show that knockdown of either total or DeltaN-specific p63 isoforms in squamous cell carcinoma (SCC9 or immortalized prostate epithelial (iPrEC cells caused a decrease in cell viability by inducing apoptosis without affecting the cell cycle. p63 silencing significantly reduced both the expression and the activity of FASN. Importantly, stable overexpression of either FASN or myristoylated AKT (myr-AKT was able to partially rescue cells from cell death induced by p63 silencing. FASN induced AKT phosphorylation and a significant reduction in cell viability was observed when FASN-overexpressing SCC9 cells were treated with an AKT inhibitor after p63 knockdown, indicating that AKT plays a major role in FASN-mediated survival. Activated AKT did not cause any alteration in the FASN protein levels but induced its activity, suggesting that the rescue from apoptosis documented in the p63-silenced cells expressing myr-AKT cells may be partially mediated by FASN. Finally, we demonstrated that p63 and FASN expression are positively associated in clinical squamous cell carcinoma samples as well as in the developing prostate. Taken together, our findings demonstrate that FASN is a functionally relevant target of p63 and is required for mediating its pro-survival effects.

  5. Oxidative stress: a key regulator of leiomyoma cell survival.

    Fletcher, Nicole M; Abusamaan, Mohammed S; Memaj, Ira; Saed, Mohammed G; Al-Hendy, Ayman; Diamond, Michael P; Saed, Ghassan M

    2017-06-01

    To determine the effects of attenuating oxidative stress with the use of dichloroacetate (DCA) on the expression of key redox enzymes myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) as well as on apoptosis. Prospective experimental study. University medical center. Cells established from myometrium and uterine fibroid from the same patients. Cells were exposed to normal (20% O 2 ) or hypoxic (2% O 2 ) conditions for 24 hours with or without DCA (20 μg/mL), a metabolic modulator that shifts anaerobic to aerobic metabolism. Nitrate/nitrite (iNOS activity indicator), iNOS, Bcl-2/Bax ratio, MPO, and caspase-3 activities and levels were determined by means of Greiss assay, real-time reverse-transcription polymerase chain reaction, and ELISA. Data were analyzed with the use of SPSS by means of one-way analysis of variance with Tukey post hoc analysis and independent t tests. MPO, iNOS, and nitrate/nitrite expression were higher in leiomyoma than in myometrial cells, and they were further enhanced by hypoxia in myometrial cells. Treatment with the use of DCA decreased MPO, iNOS, and nitrate/nitrite levels and negated the effect of hypoxia in both types of cells. Leiomyoma cells showed less apoptosis, as indicated by both caspase-3 activity and the Bcl-2/Bax ratio, than myometrial cells. Hypoxia further decreased apoptosis in myometrial cells with no further effect on leiomyoma cells. Treatment with DCA resulted in increased apoptosis in both types of cells, even in the presence of hypoxia. Shifting anaerobic to aerobic metabolism with the use of DCA resulted in an increase in apoptosis in leiomyoma cells and protected myometrial cells from the acquisition of the leiomyoma-like phenotype. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  6. Cryptoendolithic Antarctic Black Fungus Cryomyces antarcticus Irradiated with Accelerated Helium Ions: Survival and Metabolic Activity, DNA and Ultrastructural Damage

    Claudia Pacelli

    2017-10-01

    Full Text Available Space represents an extremely harmful environment for life and survival of terrestrial organisms. In the last decades, a considerable deal of attention was paid to characterize the effects of spaceflight relevant radiation on various model organisms. The aim of this study was to test the survival capacity of the cryptoendolithic black fungus Cryomyces antarcticus CCFEE 515 to space relevant radiation, to outline its endurance to space conditions. In the frame of an international radiation campaign, dried fungal colonies were irradiated with accelerated Helium ion (150 MeV/n, LET 2.2 keV/μm, up to a final dose of 1,000 Gy, as one of the space-relevant ionizing radiation. Results showed that the fungus maintained high survival and metabolic activity with no detectable DNA and ultrastructural damage, even after the highest dose irradiation. These data give clues on the resistance of life toward space ionizing radiation in general and on the resistance and responses of eukaryotic cells in particular.

  7. Ten-year survival of patients with oesophageal squamous cell ...

    Objectives. The standard predictive factors of actuarial survival such as T and N stage become less important as patients live for more than 10 years after treatment of cancer. Reports of actual 10-year survivors of oesophageal squamous cell carcinoma (SCC) are rare, and demographic and clinicopathological factors ...

  8. Mcl-1 is essential for the survival of plasma cells

    Peperzak, Victor; Vikström, Ingela; Walker, Jennifer; Glaser, Stefan P.; LePage, Melanie; Coquery, Christine M.; Erickson, Loren D.; Fairfax, Kirsten; Mackay, Fabienne; Strasser, Andreas; Nutt, Stephen L.; Tarlinton, David M.

    2013-01-01

    The long-term survival of plasma cells is entirely dependent on signals derived from their environment. These extrinsic factors presumably induce and sustain the expression of antiapoptotic proteins of the Bcl-2 family. It is uncertain whether there is specificity among Bcl-2 family members in the

  9. Susceptibility of human head and neck cancer cells to combined inhibition of glutathione and thioredoxin metabolism.

    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. Murine Th9 cells promote the survival of myeloid dendritic cells in cancer immunotherapy.

    Park, Jungsun; Li, Haiyan; Zhang, Mingjun; Lu, Yong; Hong, Bangxing; Zheng, Yuhuan; He, Jin; Yang, Jing; Qian, Jianfei; Yi, Qing

    2014-08-01

    Dendritic cells (DCs) are professional antigen-presenting cells to initiate immune responses, and DC survival time is important for affecting the strength of T-cell responses. Interleukin (IL)-9-producing T-helper (Th)-9 cells play an important role in anti-tumor immunity. However, it is unclear how Th9 cells communicate with DCs. In this study, we investigated whether murine Th9 cells affected the survival of myeloid DCs. DCs derived from bone marrow of C57BL/6 mice were cocultured with Th9 cells from OT-II mice using transwell, and the survival of DCs was examined. DCs cocultured with Th9 cells had longer survival and fewer apoptotic cells than DCs cultured alone in vitro. In melanoma B16-OVA tumor-bearing mice, DCs conditioned by Th9 cells lived longer and induced stronger anti-tumor response than control DCs did in vivo. Mechanistic studies revealed that IL-3 but not IL-9 secreted by Th9 cells was responsible for the prolonged survival of DCs. IL-3 upregulated the expression of anti-apoptotic protein Bcl-xL and activated p38, ERK and STAT5 signaling pathways in DCs. Taken together, our data provide the first evidence that Th9 cells can promote the survival of DCs through IL-3, and will be helpful for designing Th9 cell immunotherapy and more effective DC vaccine for human cancers.

  11. Chromosome aberrations and cell survival in irradiated mammalian cells

    Tremp, J.

    1981-01-01

    A possible correlation between chromosome aberrations and reduced proliferation capacity or cell death was investigated. Synchronized Chinese hamster fibroblast cells were irradiated with 300 rad of x rays in early G 1 . Despite synchronization the cells reached the subsequent mitosis at different times. The frequency of chromosome aberrations was determined in the postirradiation division at 2-h intervals. The highest frequency occurred in cells with a first cell cycle of medium length. The colony-forming ability of mitotic cells was measured in parallel samples by following the progress of individual mitoses. The proportion of cells forming macrocolonies decreased with increasing cell cycle length, and the number of non-colony-forming cells increased. Irrespective of various first cell cycle lengths and different frequencies of chromosome aberrations, the number of cells forming microcolonies remained constant. A correlation was found between the absence of chromosome aberrations and the ability of cells to form macrocolonies. However, cells with a long first cell cycle formed fewer macrocolonies than expected

  12. Lysosomal cysteine peptidases - Molecules signaling tumor cell death and survival.

    Pišlar, Anja; Perišić Nanut, Milica; Kos, Janko

    2015-12-01

    Lysosomal cysteine peptidases - cysteine cathepsins - are general intracellular protein-degrading enzymes that control also a variety of specific physiological processes. They can trigger irreversible events leading to signal transduction and activation of signaling pathways, resulting in cell survival and proliferation or cell death. In cancer cells, lysosomal cysteine peptidases are involved in multiple processes during malignant progression. Their translocation from the endosomal/lysosomal pathway to nucleus, cytoplasm, plasma membrane and extracellular space enables the activation and remodeling of a variety of tumor promoting proteins. Thus, lysosomal cysteine peptidases interfere with cytokine/chemokine signaling, regulate cell adhesion and migration and endocytosis, are involved in the antitumor immune response and apoptosis, and promote cell invasion, angiogenesis and metastasis. Further, lysosomal cysteine peptidases modify growth factors and receptors involved in tyrosine kinase dependent pathways such as MAPK, Akt and JNK, thus representing key signaling tools for the activation of tumor cell growth and proliferation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Effect of mercury on survival, metabolism and behavior of larval Uca pugilator (Brachyura)

    DeCoursey, P J; Vernberg, W B

    1972-01-01

    A battery of tests was used to determine the effects of three dilute mercuric chloride solutions on larval stages (Zoea I, III, V) of the fiddler crab Uca pugilator(Bosc). The influence of both acute and chronic exposures on viability, oxygen consumption, and swimming activity was measured. No stage V and only a few stage I or III larvae were able to survive a concentration of 9 x 10/sup -7/ M HgCl/sub 2/ (0.18 ppm Hg) longer than 24 hr; an exposure as short as 6 hr resulted in reduced metabolism and swimming rate of all stages. Although concentrations of 9 x 10/sup -9/ M Hg Cl/sub 2/ (0.0018 ppm) and 9 x 10/sup -11/ M HgCl/sub 2/ (0.000018 ppm) were sublethal, 24-hr exposures did affect metabolism and swimming. Some larvae reared in the more dilute mercury solutions developed to the megalopa stage, but survival was reduced in relation to the mercury concentration. The data from all tests suggest that toxicity of mercury increases with larval age. 20 references, 6 figures.

  14. Heterogeneity of Glucose Metabolism in Esophageal Cancer Measured by Fractal Analysis of Fluorodeoxyglucose Positron Emission Tomography Image: Correlation between Metabolic Heterogeneity and Survival.

    Tochigi, Toru; Shuto, Kiyohiko; Kono, Tsuguaki; Ohira, Gaku; Tohma, Takayuki; Gunji, Hisashi; Hayano, Koichi; Narushima, Kazuo; Fujishiro, Takeshi; Hanaoka, Toshiharu; Akutsu, Yasunori; Okazumi, Shinichi; Matsubara, Hisahiro

    2017-01-01

    Intratumoral heterogeneity is a well-recognized characteristic feature of cancer. The purpose of this study is to assess the heterogeneity of the intratumoral glucose metabolism using fractal analysis, and evaluate its prognostic value in patients with esophageal squamous cell carcinoma (ESCC). 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) studies of 79 patients who received curative surgery were evaluated. FDG-PET images were analyzed using fractal analysis software, where differential box-counting method was employed to calculate the fractal dimension (FD) of the tumor lesion. Maximum standardized uptake value (SUVmax) and FD were compared with overall survival (OS). The median SUVmax and FD of ESCCs in this cohort were 13.8 and 1.95, respectively. In univariate analysis performed using Cox's proportional hazard model, T stage and FD showed significant associations with OS (p = 0.04, p heterogeneity measured by fractal analysis can be a novel imaging biomarker for survival in patients with ESCC. © 2016 S. Karger AG, Basel.

  15. From gametogenesis and stem cells to cancer: common metabolic themes.

    Pereira, Sandro L; Rodrigues, Ana Sofia; Sousa, Maria Inês; Correia, Marcelo; Perestrelo, Tânia; Ramalho-Santos, João

    2014-01-01

    Both pluripotent stem cells (PSCs) and cancer cells have been described as having similar metabolic pathways, most notably a penchant for favoring glycolysis even under aerobiosis, suggesting common themes that might be explored for both stem cell differentiation and anti-oncogenic purposes. A search of the scientific literature available in the PubMed/Medline was conducted for studies on metabolism and mitochondrial function related to gametogenesis, early development, stem cells and cancers in the reproductive system, notably breast, prostate, ovarian and testicular cancers. Both PSCs and some types of cancer cells, particularly reproductive cancers, were found to obtain energy mostly by glycolysis, often reducing mitochondrial activity and oxidative phosphorylation. This strategy links proliferating cells, allowing for the biosynthesis reactions necessary for cell division. Interventions that affect metabolic pathways, and force cells to change their preferences, can lead to shifts in cell status, increasing either pluripotency or differentiation of stem cells, and causing cancer cells to become more or less aggressive. Interestingly metabolic changes in many cases seemed to lead to cell transformation, not necessarily follow it, suggesting a direct role of metabolic choices in influencing the (epi)genetic program of different cell types. There are uncanny similarities between PSCs and cancer cells at the metabolic level. Furthermore, metabolism may also play a direct role in cell status and targeting metabolic pathways could therefore be a promising strategy for both the control of cancer cell proliferation and the regulation of stem cell physiology, in terms of manipulating stem cells toward relevant phenotypes that may be important for tissue engineering, or making cancer cells become less tumorigenic. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For

  16. Neutron-energy-dependent cell survival and oncogenic transformation.

    Miller, R C; Marino, S A; Martin, S G; Komatsu, K; Geard, C R; Brenner, D J; Hall, E J

    1999-12-01

    Both cell lethality and neoplastic transformation were assessed for C3H10T1/2 cells exposed to neutrons with energies from 0.040 to 13.7 MeV. Monoenergetic neutrons with energies from 0.23 to 13.7 MeV and two neutron energy spectra with average energies of 0.040 and 0.070 MeV were produced with a Van de Graaff accelerator at the Radiological Research Accelerator Facility (RARAF) in the Center for Radiological Research of Columbia University. For determination of relative biological effectiveness (RBE), cells were exposed to 250 kVp X rays. With exposures to 250 kVp X rays, both cell survival and radiation-induced oncogenic transformation were curvilinear. Irradiation of cells with neutrons at all energies resulted in linear responses as a function of dose for both biological endpoints. Results indicate a complex relationship between RBEm and neutron energy. For both survival and transformation, RBEm was greatest for cells exposed to 0.35 MeV neutrons. RBEm was significantly less at energies above or below 0.35 MeV. These results are consistent with microdosimetric expectation. These results are also compatible with current assessments of neutron radiation weighting factors for radiation protection purposes. Based on calculations of dose-averaged LET, 0.35 MeV neutrons have the greatest LET and therefore would be expected to be more biologically effective than neutrons of greater or lesser energies.

  17. Aging, metabolism and stem cells: Spotlight on muscle stem cells.

    García-Prat, Laura; Muñoz-Cánoves, Pura

    2017-04-15

    All tissues and organs undergo a progressive regenerative decline as they age. This decline has been mainly attributed to loss of stem cell number and/or function, and both stem cell-intrinsic changes and alterations in local niches and/or systemic environment over time are known to contribute to the stem cell aging phenotype. Advancing in the molecular understanding of the deterioration of stem cell cells with aging is key for targeting the specific causes of tissue regenerative dysfunction at advanced stages of life. Here, we revise exciting recent findings on why stem cells age and the consequences on tissue regeneration, with a special focus on regeneration of skeletal muscle. We also highlight newly identified common molecular pathways affecting diverse types of aging stem cells, such as altered proteostasis, metabolism, or senescence entry, and discuss the questions raised by these findings. Finally, we comment on emerging stem cell rejuvenation strategies, principally emanating from studies on muscle stem cells, which will surely burst tissue regeneration research for future benefit of the increasing human aging population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Discrete dynamic modeling of T cell survival signaling networks

    Zhang, Ranran

    2009-03-01

    Biochemistry-based frameworks are often not applicable for the modeling of heterogeneous regulatory systems that are sparsely documented in terms of quantitative information. As an alternative, qualitative models assuming a small set of discrete states are gaining acceptance. This talk will present a discrete dynamic model of the signaling network responsible for the survival and long-term competence of cytotoxic T cells in the blood cancer T-LGL leukemia. We integrated the signaling pathways involved in normal T cell activation and the known deregulations of survival signaling in leukemic T-LGL, and formulated the regulation of each network element as a Boolean (logic) rule. Our model suggests that the persistence of two signals is sufficient to reproduce all known deregulations in leukemic T-LGL. It also indicates the nodes whose inactivity is necessary and sufficient for the reversal of the T-LGL state. We have experimentally validated several model predictions, including: (i) Inhibiting PDGF signaling induces apoptosis in leukemic T-LGL. (ii) Sphingosine kinase 1 and NFκB are essential for the long-term survival of T cells in T-LGL leukemia. (iii) T box expressed in T cells (T-bet) is constitutively activated in the T-LGL state. The model has identified potential therapeutic targets for T-LGL leukemia and can be used for generating long-term competent CTL necessary for tumor and cancer vaccine development. The success of this model, and of other discrete dynamic models, suggests that the organization of signaling networks has an determining role in their dynamics. Reference: R. Zhang, M. V. Shah, J. Yang, S. B. Nyland, X. Liu, J. K. Yun, R. Albert, T. P. Loughran, Jr., Network Model of Survival Signaling in LGL Leukemia, PNAS 105, 16308-16313 (2008).

  19. Ptpmt1 induced by HIF-2α regulates the proliferation and glucose metabolism in erythroleukemia cells

    Xu, Qin-Qin [High Altitude Medicine of Ministry of Chinese Education and Research Center for High Altitude Medicine, Qinghai University, Xining, 810001 (China); Qinghai Provincial People' s Hospital, Xining (China); Xiao, Feng-Jun; Sun, Hui-Yan [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing, 100850 (China); Shi, Xue-Feng [High Altitude Medicine of Ministry of Chinese Education and Research Center for High Altitude Medicine, Qinghai University, Xining, 810001 (China); Qinghai Provincial People' s Hospital, Xining (China); Wang, Hua; Yang, Yue-Feng; Li, Yu-Xiang [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing, 100850 (China); Wang, Li-Sheng, E-mail: wangls@bmi.ac.cn [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing, 100850 (China); Ge, Ri-Li, E-mail: geriligao@hotmail.com [High Altitude Medicine of Ministry of Chinese Education and Research Center for High Altitude Medicine, Qinghai University, Xining, 810001 (China)

    2016-03-18

    Hypoxia provokes metabolism misbalance, mitochondrial dysfunction and oxidative stress in both human and animal cells. However, the mechanisms which hypoxia causes mitochondrial dysfunction and energy metabolism misbalance still remain unclear. In this study, we presented evidence that mitochondrial phosphatase Ptpmt1 is a hypoxia response molecule that regulates cell proliferation, survival and glucose metabolism in human erythroleukemia TF-1 cells. Exposure to hypoxia or DFO treatment results in upregulation of HIF1-α, HIF-2α and Ptpmt1. Only inhibition of HIF-2α by shRNA transduction reduces Ptpmt1 expression in TF-1 cells under hypoxia. Ptpmt1 inhibitor suppresses the growth and induces apoptosis of TF-1 cells. Furthermore, we demonstrated that Ptpmt1 inhibition reduces the Glut1 and Glut3 expression and decreases the glucose consumption in TF-1 cells. In additional, Ptpmt1 knockdown also results in the mitochondrial dysfunction determined by JC1 staining. These results delineate a key role for HIF-2α-induced Ptpmt1 upregulation in proliferation, survival and glucose metabolism of erythroleukemia cells. It is indicated that Ptpmt1 plays important roles in hypoxia-induced cell metabolism and mitochondrial dysfunction. - Highlights: • Hypoxia induces upregulation of HIF-1α, HIF-2α and Ptpmt1; HIF-2a induces Ptpmt1 upregulation in TF-1 cells. • PTPMT-1 inhibition reduces growth and induces apoptosis of TF-1 cells. • PTPMT1 inhibition downregulates Glut-1, Glut-3 expression and reduces glucose consumption.

  20. AMPK promotes survival of c-Myc-positive melanoma cells by suppressing oxidative stress.

    Kfoury, Alain; Armaro, Marzia; Collodet, Caterina; Sordet-Dessimoz, Jessica; Giner, Maria Pilar; Christen, Stefan; Moco, Sofia; Leleu, Marion; de Leval, Laurence; Koch, Ute; Trumpp, Andreas; Sakamoto, Kei; Beermann, Friedrich; Radtke, Freddy

    2018-03-01

    Although c-Myc is essential for melanocyte development, its role in cutaneous melanoma, the most aggressive skin cancer, is only partly understood. Here we used the Nras Q61K INK4a -/- mouse melanoma model to show that c-Myc is essential for tumor initiation, maintenance, and metastasis. c-Myc-expressing melanoma cells were preferentially found at metastatic sites, correlated with increased tumor aggressiveness and high tumor initiation potential. Abrogation of c-Myc caused apoptosis in primary murine and human melanoma cells. Mechanistically, c-Myc-positive melanoma cells activated and became dependent on the metabolic energy sensor AMP-activated protein kinase (AMPK), a metabolic checkpoint kinase that plays an important role in energy and redox homeostasis under stress conditions. AMPK pathway inhibition caused apoptosis of c-Myc-expressing melanoma cells, while AMPK activation protected against cell death of c-Myc-depleted melanoma cells through suppression of oxidative stress. Furthermore, TCGA database analysis of early-stage human melanoma samples revealed an inverse correlation between C-MYC and patient survival, suggesting that C-MYC expression levels could serve as a prognostic marker for early-stage disease. © 2018 The Authors.

  1. Activated ovarian endothelial cells promote early follicular development and survival.

    Kedem, Alon; Aelion-Brauer, Anate; Guo, Peipei; Wen, Duancheng; Ding, Bi-Sen; Lis, Raphael; Cheng, Du; Sandler, Vladislav M; Rafii, Shahin; Rosenwaks, Zev

    2017-09-19

    New data suggests that endothelial cells (ECs) elaborate essential "angiocrine factors". The aim of this study is to investigate the role of activated ovarian endothelial cells in early in-vitro follicular development. Mouse ovarian ECs were isolated using magnetic cell sorting or by FACS and cultured in serum free media. After a constitutive activation of the Akt pathway was initiated, early follicles (50-150 um) were mechanically isolated from 8-day-old mice and co-cultured with these activated ovarian endothelial cells (AOEC) (n = 32), gel (n = 24) or within matrigel (n = 27) in serum free media for 14 days. Follicular growth, survival and function were assessed. After 6 passages, flow cytometry showed 93% of cells grown in serum-free culture were VE-cadherin positive, CD-31 positive and CD 45 negative, matching the known EC profile. Beginning on day 4 of culture, we observed significantly higher follicular and oocyte growth rates in follicles co-cultured with AOECs compared with follicles on gel or matrigel. After 14 days of culture, 73% of primary follicles and 83% of secondary follicles co-cultured with AOEC survived, whereas the majority of follicles cultured on gel or matrigel underwent atresia. This is the first report of successful isolation and culture of ovarian ECs. We suggest that co-culture with activated ovarian ECs promotes early follicular development and survival. This model is a novel platform for the in vitro maturation of early follicles and for the future exploration of endothelial-follicular communication. In vitro development of early follicles necessitates a complex interplay of growth factors and signals required for development. Endothelial cells (ECs) may elaborate essential "angiocrine factors" involved in organ regeneration. We demonstrate that co-culture with ovarian ECs enables culture of primary and early secondary mouse ovarian follicles.

  2. Mitochondrial respiratory modifiers confer survival advantage by facilitating DNA repair in cancer cells

    Chauhan, Ankit; Khanna, Suchit; Singh, Saurabh; Rai, Yogesh; Soni, Ravi; Kalra, Namita; Dwarakanath, B.S.; Bhatt, Anant Narayan

    2014-01-01

    High rate of aerobic glycolysis (Warburg effect), one of the primary hallmarks of cancer cells, acquired during the multistep development of tumors is also responsible for therapeutic resistance. Underlying this hallmark is the compromised respiratory metabolism that contributes to the acquisition of the glycolytic phenotype for sustained ATP production and cell proliferation. Nevertheless, the exact mechanisms underlying the glycolysis-linked radio-resistance in cancer cells remain elusive. In this study, we transiently elevated glycolysis by treating human cell lines (HEK293, BMG-1 and OCT-1) with mitochondrial respiratory modifiers (MRMs) viz. 2,4-dinitrophenol, Photosan-3, and Methylene blue to examine if transient stimulation of glycolysis before irradiation using MRMs is sufficient to confer radioresistance. Treatment with MRMs led to a significant (two-fold) increase in glucose consumption and lactate production together with a robust increase in the protein levels of two key regulators of glucose metabolism, i.e. GLUT-1 and HK-II. MRMs also enhanced the clonogenic survival and facilitated DNA repair by activating both non-homologous end joining (NHEJ) and homologous recombination (HR) pathways of DNA double strand break repair leading to reduction in radiation-induced cytogenetic damage (micronuclei formation) in these cells. Inhibition of glucose uptake by inhibitors like 2-deoxy-D-glucose (2-DG), 3-bromo pyruvate (3-BP) and fasentin under conditions of stimulated glycolysis not only reversed the effect but also sensitized the cells to radiation more profoundly. The inhibition of glycolysis using 2-DG also reduced the levels of Ku 70 (NHEJ) and Rad-51 (HR) proteins. Thus, our results suggest that enhanced glycolysis in cancer cells may confer radio-resistance and offers survival advantage partly by enhancing the repair of DNA damage. (author)

  3. Tolerance to the antimicrobial peptide colistin in Pseudomonas aeruginosa biofilms is linked to metabolically active cells, and depends on the pmr and mexAB-oprM genes

    Pamp, Sünje Johanna; Gjermansen, Morten; Johansen, Helle Krogh

    2008-01-01

    -mediated killing in biofilms, conventional antimicrobial compounds such as ciprofloxacin and tetracycline were found to specifically kill the subpopulation of metabolically active biofilm cells, whereas the subpopulation exhibiting low metabolic activity survived the treatment. Consequently, targeting the two...... physiologically distinct subpopulations by combined antimicrobial treatment with either ciprofloxacin and colistin or tetracycline and colistin almost completely eradicated all biofilm cells....

  4. Cell survival in spheroids irradiated with heavy-ion beams

    Rodriguez, A.; Alpen, E.L.

    1981-01-01

    Biological investigations with accelerated heavy ions have been carried out regularly at the Lawrence Berkeley Laboratory Bevalac for the past four years. Most of the cellular investigations have been conducted on cell monolayer and suspension culture systems. The studies to date suggest that heavy charged particle beams may offer some radiotherapeutic advantages over conventional radiotherapy sources. The advantages are thought to lie primarily in an increased relative biological effectiveness (RBE), a decrease in the oxygen enhancement ratio (OER), and better tissue distribution dose. Experiments reported here were conducted with 400 MeV/amu carbon ions and 425 MeV/amu neon ions, using a rat brain gliosarcoma cell line grown as multicellular spheroids. Studies have been carried out with x-rays and high-energy carbon and neon ion beams. These studies evaluate high-LET (linear energy transfer) cell survival in terms of RBE and the possible contributions of intercellular communication. Comparisons were made of the post-irradiation survival characteristics for cells irradiated as multicellular spheroids (approximately 100 μm and 300 μm diameters) and for cells irradiated in suspension. These comparisons were made between 225-kVp x-rays, 400 MeV/amu carbon ions, and 425 MeV/amu neon ions

  5. Survival rate of eukaryotic cells following electrophoretic nanoinjection.

    Simonis, Matthias; Hübner, Wolfgang; Wilking, Alice; Huser, Thomas; Hennig, Simon

    2017-01-25

    Insertion of foreign molecules such as functionalized fluorescent probes, antibodies, or plasmid DNA to living cells requires overcoming the plasma membrane barrier without harming the cell during the staining process. Many techniques such as electroporation, lipofection or microinjection have been developed to overcome the cellular plasma membrane, but they all result in reduced cell viability. A novel approach is the injection of cells with a nanopipette and using electrophoretic forces for the delivery of molecules. The tip size of these pipettes is approximately ten times smaller than typical microinjection pipettes and rather than pressure pulses as delivery method, moderate DC electric fields are used to drive charged molecules out of the tip. Here, we show that this approach leads to a significantly higher survival rate of nanoinjected cells and that injection with nanopipettes has a significantly lower impact on the proliferation behavior of injected cells. Thus, we propose that injection with nanopipettes using electrophoretic delivery is an excellent alternative when working with valuable and rare living cells, such as primary cells or stem cells.

  6. Survival rate of eukaryotic cells following electrophoretic nanoinjection

    Simonis, Matthias; Hübner, Wolfgang; Wilking, Alice; Huser, Thomas; Hennig, Simon

    2017-01-01

    Insertion of foreign molecules such as functionalized fluorescent probes, antibodies, or plasmid DNA to living cells requires overcoming the plasma membrane barrier without harming the cell during the staining process. Many techniques such as electroporation, lipofection or microinjection have been developed to overcome the cellular plasma membrane, but they all result in reduced cell viability. A novel approach is the injection of cells with a nanopipette and using electrophoretic forces for the delivery of molecules. The tip size of these pipettes is approximately ten times smaller than typical microinjection pipettes and rather than pressure pulses as delivery method, moderate DC electric fields are used to drive charged molecules out of the tip. Here, we show that this approach leads to a significantly higher survival rate of nanoinjected cells and that injection with nanopipettes has a significantly lower impact on the proliferation behavior of injected cells. Thus, we propose that injection with nanopipettes using electrophoretic delivery is an excellent alternative when working with valuable and rare living cells, such as primary cells or stem cells. PMID:28120926

  7. Red cell survival and sequestration in acute intermittent porphyria

    Nawalkha, P.L.; Soni, S.G.; Agrawal, V.K.; Misra, S.N.

    1980-01-01

    Life span and sequestration of red cells have been studied in twenty one proved cases of acute intermittent porphyria of different age and sex group from Bikaner District, Rajasthan State (India). Chromium-51 labelled red cells were used in the study and the excess count method of Bughe Jones and Szur was used to calculate the index of sequestration. The mean apparent half survival time of erythrocytes in the control subjects was 25.9 +- 2.9 (S.D.) days and the same in the prophyria patients was 27.0 +- 3.8 days. This shows that the life span of red cells is normal in both the patient and the control. Excess destruction of red blood cells was found to take place in either spleen or liver in the disease and no excess accumulation of erythrocytes occurred over spleen as compared to liver. (M.G.B.)

  8. Glucose consumption of inflammatory cells masks metabolic deficits in the brain.

    Backes, Heiko; Walberer, Maureen; Ladwig, Anne; Rueger, Maria A; Neumaier, Bernd; Endepols, Heike; Hoehn, Mathias; Fink, Gereon R; Schroeter, Michael; Graf, Rudolf

    2016-03-01

    Inflammatory cells such as microglia need energy to exert their functions and to maintain their cellular integrity and membrane potential. Subsequent to cerebral ischemia, inflammatory cells infiltrate tissue with limited blood flow where neurons and astrocytes died due to insufficient supply with oxygen and glucose. Using dual tracer positron emission tomography (PET), we found that concomitant with the presence of inflammatory cells, transport and consumption of glucose increased up to normal levels but returned to pathological levels as soon as inflammatory cells disappeared. Thus, inflammatory cells established sufficient glucose supply to satisfy their energy demands even in regions with insufficient supply for neurons and astrocytes to survive. Our data suggest that neurons and astrocytes died from oxygen deficiency and inflammatory cells metabolized glucose non-oxidatively in regions with residual availability. As a consequence, glucose metabolism of inflammatory cells can mask metabolic deficits in neurodegenerative diseases. We further found that the PET tracer did not bind to inflammatory cells in severely hypoperfused regions and thus only a part of the inflammation was detected. We conclude that glucose consumption of inflammatory cells should be taken into account when analyzing disease-related alterations of local cerebral metabolism. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Random distribution of nucleoli in metabolic cells

    Beckman, R.J.; Waterman, M.S.

    1977-01-01

    Hasofer (1974) has studied a probabilistic model for the fusion of nucleoli in metabolic cells. The nucleoli are uniformly distributed at points in the nucleus, assumed to be a sphere. The nucleoli grow from a point to a maximum size during interphase, and fusion is said to occur if the nucleoli touch. For this model, Hasofer calculated the probability of fusion and found it much smaller than experimental data would indicate. Experimental data of this type is taken by use of a microscope where a two-dimensional view or projection of the three-dimensional cell is obtained. Hasofer implicitly assumes that actual fusion can be distinguished from the case where the two nucleoli do not touch but their two-dimensional projections overlap. It is assumed, in this letter, that these two cases cannot be distinguished. The probability obtained by Beckman and Waterman is larger than Hasofer's and a much better fit to the experimental data is obtained. Even if true fusion can be unfailingly distinguished from overlap of the two-dimensional projections, it is hoped that these calculations will allow someone to propose the correct (non-uniform) model. It is concluded, for the assumptions used, that there is not sufficient evidence to reject the hypothesis of uniform distribution of the nucleoli.

  10. Bovine lactoferrin regulates cell survival, apoptosis and inflammation in intestinal epithelial cells and preterm pig intestine.

    Nguyen, Duc Ninh; Jiang, Pingping; Stensballe, Allan; Bendixen, Emøke; Sangild, Per T; Chatterton, Dereck E W

    2016-04-29

    Bovine lactoferrin (bLF) may modulate neonatal intestinal inflammation. Previous studies in intestinal epithelial cells (IECs) indicated that moderate bLF doses enhance proliferation whereas high doses trigger inflammation. To further elucidate cellular mechanisms, we profiled the porcine IEC proteome after stimulation with bLF at 0, 0.1, 1 and 10g/L by LC-MS-based proteomics. Key pathways were analyzed in the intestine of formula-fed preterm pigs with and without supplementation of 10g/L bLF. Levels of 123 IEC proteins were altered by bLF. Low bLF doses (0.1-1g/L) up-regulated 11 proteins associated with glycolysis, energy metabolism and protein synthesis, indicating support of cell survival. In contrast, a high bLF dose (10g/L) up-regulated three apoptosis-inducing proteins, down-regulated five anti-apoptotic and proliferation-inducing proteins and 15 proteins related to energy and amino acid metabolism, and altered three proteins enhancing the hypoxia inducible factor-1 (HIF-1) pathway. In the preterm pig intestine, bLF at 10g/L decreased villus height/crypt depth ratio and up-regulated the Bax/Bcl-2 ratio and HIF-1α, indicating elevated intestinal apoptosis and inflammation. In conclusion, bLF dose-dependently affects IECs via metabolic, apoptotic and inflammatory pathways. It is important to select an appropriate dose when feeding neonates with bLF to avoid detrimental effects exerted by excessive doses. The present work elucidates dose-dependent effects of bLF on the proteomic changes of IECs in vitro supplemented with data from a preterm pig study confirming detrimental effects of enteral feeding with the highest dose of bLF (10g/L). The study contributes to further understanding on mechanisms that bLF, as an important milk protein, can regulate the homeostasis of the immature intestine. Results from this study urge neonatologists to carefully consider the dose of bLF to supplement into infant formula used for preterm neonates. Copyright © 2016 Elsevier B

  11. Control of neural stem cell survival by electroactive polymer substrates.

    Vanessa Lundin

    Full Text Available Stem cell function is regulated by intrinsic as well as microenvironmental factors, including chemical and mechanical signals. Conducting polymer-based cell culture substrates provide a powerful tool to control both chemical and physical stimuli sensed by stem cells. Here we show that polypyrrole (PPy, a commonly used conducting polymer, can be tailored to modulate survival and maintenance of rat fetal neural stem cells (NSCs. NSCs cultured on PPy substrates containing different counter ions, dodecylbenzenesulfonate (DBS, tosylate (TsO, perchlorate (ClO(4 and chloride (Cl, showed a distinct correlation between PPy counter ion and cell viability. Specifically, NSC viability was high on PPy(DBS but low on PPy containing TsO, ClO(4 and Cl. On PPy(DBS, NSC proliferation and differentiation was comparable to standard NSC culture on tissue culture polystyrene. Electrical reduction of PPy(DBS created a switch for neural stem cell viability, with widespread cell death upon polymer reduction. Coating the PPy(DBS films with a gel layer composed of a basement membrane matrix efficiently prevented loss of cell viability upon polymer reduction. Here we have defined conditions for the biocompatibility of PPy substrates with NSC culture, critical for the development of devices based on conducting polymers interfacing with NSCs.

  12. Metabolism

    ... lin), which signals cells to increase their anabolic activities. Metabolism is a complicated chemical process, so it's not ... how those enzymes or hormones work. When the metabolism of body chemicals is ... Hyperthyroidism (pronounced: hi-per-THIGH-roy-dih-zum). Hyperthyroidism ...

  13. Upregulation of LYAR induces neuroblastoma cell proliferation and survival.

    Sun, Yuting; Atmadibrata, Bernard; Yu, Denise; Wong, Matthew; Liu, Bing; Ho, Nicholas; Ling, Dora; Tee, Andrew E; Wang, Jenny; Mungrue, Imran N; Liu, Pei Y; Liu, Tao

    2017-09-01

    The N-Myc oncoprotein induces neuroblastoma by regulating gene transcription and consequently causing cell proliferation. Paradoxically, N-Myc is well known to induce apoptosis by upregulating pro-apoptosis genes, and it is not clear how N-Myc overexpressing neuroblastoma cells escape N-Myc-mediated apoptosis. The nuclear zinc finger protein LYAR has recently been shown to modulate gene expression by forming a protein complex with the protein arginine methyltransferase PRMT5. Here we showed that N-Myc upregulated LYAR gene expression by binding to its gene promoter. Genome-wide differential gene expression studies revealed that knocking down LYAR considerably upregulated the expression of oxidative stress genes including CHAC1, which depletes intracellular glutathione and induces oxidative stress. Although knocking down LYAR expression with siRNAs induced oxidative stress, neuroblastoma cell growth inhibition and apoptosis, co-treatment with the glutathione supplement N-acetyl-l-cysteine or co-transfection with CHAC1 siRNAs blocked the effect of LYAR siRNAs. Importantly, high levels of LYAR gene expression in human neuroblastoma tissues predicted poor event-free and overall survival in neuroblastoma patients, independent of the best current markers for poor prognosis. Taken together, our data suggest that LYAR induces proliferation and promotes survival of neuroblastoma cells by repressing the expression of oxidative stress genes such as CHAC1 and suppressing oxidative stress, and identify LYAR as a novel co-factor in N-Myc oncogenesis.

  14. Stem cell metabolism in tissue development and aging

    Shyh-Chang, Ng; Daley, George Q.; Cantley, Lewis C.

    2013-01-01

    Recent advances in metabolomics and computational analysis have deepened our appreciation for the role of specific metabolic pathways in dictating cell fate. Once thought to be a mere consequence of the state of a cell, metabolism is now known to play a pivotal role in dictating whether a cell proliferates, differentiates or remains quiescent. Here, we review recent studies of metabolism in stem cells that have revealed a shift in the balance between glycolysis, mitochondrial oxidative phosphorylation and oxidative stress during the maturation of adult stem cells, and during the reprogramming of somatic cells to pluripotency. These insights promise to inform strategies for the directed differentiation of stem cells and to offer the potential for novel metabolic or pharmacological therapies to enhance regeneration and the treatment of degenerative disease. PMID:23715547

  15. Metabolic Plasticity of Stem Cells and Macrophages in Cancer

    Jelena Krstic

    2017-08-01

    Full Text Available In addition to providing essential molecules for the overall function of cells, metabolism plays an important role in cell fate and can be affected by microenvironmental stimuli as well as cellular interactions. As a specific niche, tumor microenvironment (TME, consisting of different cell types including stromal/stem cells and immune cells, is characterized by distinct metabolic properties. This review will be focused on the metabolic plasticity of mesenchymal stromal/stem cells (MSC and macrophages in TME, as well as on how the metabolic state of cancer stem cells (CSC, as key drivers of oncogenesis, affects their generation and persistence. Namely, heterogenic metabolic phenotypes of these cell populations, which include various levels of dependence on glycolysis or oxidative phosphorylation are closely linked to their complex roles in cancer progression. Besides well-known extrinsic factors, such as cytokines and growth factors, the differentiation and activation states of CSC, MSC, and macrophages are coordinated by metabolic reprogramming in TME. The significance of mutual metabolic interaction between tumor stroma and cancer cells in the immune evasion and persistence of CSC is currently under investigation.

  16. Association study of genetic variants in estrogen metabolic pathway genes and colorectal cancer risk and survival.

    Li, Shuwei; Xie, Lisheng; Du, Mulong; Xu, Kaili; Zhu, Lingjun; Chu, Haiyan; Chen, Jinfei; Wang, Meilin; Zhang, Zhengdong; Gu, Dongying

    2018-05-16

    Although studies have investigated the association of genetic variants and the abnormal expression of estrogen-related genes with colorectal cancer risk, the evidence remains inconsistent. We clarified the relationship of genetic variants in estrogen metabolic pathway genes with colorectal cancer risk and survival. A case-control study was performed to assess the association of single-nucleotide polymorphisms (SNPs) in ten candidate genes with colorectal cancer risk in a Chinese population. A logistic regression model and Cox regression model were used to calculate SNP effects on colorectal cancer susceptibility and survival, respectively. Expression quantitative trait loci (eQTL) analysis was conducted using the Genotype-Tissue Expression (GTEx) project dataset. The sequence kernel association test (SKAT) was used to perform gene-set analysis. Colorectal cancer risk and rs3760806 in SULT2B1 were significantly associated in both genders [male: OR = 1.38 (1.15-1.66); female: OR = 1.38 (1.13-1.68)]. Two SNPs in SULT1E1 were related to progression-free survival (PFS) [rs1238574: HR = 1.24 (1.02-1.50), P = 2.79 × 10 -2 ; rs3822172: HR = 1.30 (1.07-1.57), P = 8.44 × 10 -3 ] and overall survival (OS) [rs1238574: HR = 1.51 (1.16-1.97), P = 2.30 × 10 -3 ; rs3822172: HR = 1.53 (1.67-2.00), P = 2.03 × 10 -3 ]. Moreover, rs3760806 was an eQTL for SULT2B1 in colon samples (transverse: P = 3.6 × 10 -3 ; sigmoid: P = 1.0 × 10 -3 ). SULT2B1 expression was significantly higher in colorectal tumor tissues than in normal tissues in the Cancer Genome Atlas (TCGA) database (P colorectal cancer susceptibility and survival.

  17. Selective Mitochondrial Uptake of MKT-077 Can Suppress Medullary Thyroid Carcinoma Cell Survival and

    Dmytro Starenki

    2015-12-01

    Full Text Available BackgroundMedullary thyroid carcinoma (MTC is a neuroendocrine tumor mainly caused by mutations in the rearranged during transfection (RET proto-oncogene. Not all patients with progressive MTC respond to current therapy inhibiting RET, demanding additional therapeutic strategies. We recently demonstrated that disrupting mitochondrial metabolism using a mitochondria-targeted agent or by depleting a mitochondrial chaperone effectively suppressed human MTC cells in culture and in mouse xenografts by inducing apoptosis and RET downregulation. These observations led us to hypothesize that mitochondria are potential therapeutic targets for MTC. This study further tests this hypothesis using1-ethyl-2-[[3-ethyl-5-(3-methylbenzothiazolin-2-yliden]-4-oxothiazolidin-2-ylidenemethyl] pyridinium chloride (MKT-077, a water-soluble rhodocyanine dye analogue, which can selectively accumulate in mitochondria.MethodsThe effects of MKT-077 on cell proliferation, survival, expression of RET and tumor protein 53 (TP53, and mitochondrial activity were determined in the human MTC lines in culture and in mouse xenografts.ResultsMKT-077 induced cell cycle arrest in TT and MZ-CRC-1. Intriguingly, MKT-077 also induced RET downregulation and strong cell death responses in TT cells, but not in MZ-CRC-1 cells. This discrepancy was mainly due to the difference between the capacities of these cell lines to retain MKT-077 in mitochondria. The cytotoxicity of MKT-077 in TT cells was mainly attributed to oxidative stress while being independent of TP53. MKT-077 also effectively suppressed tumor growth of TT xenografts.ConclusionMKT-077 can suppress cell survival of certain MTC subtypes by accumulating in mitochondria and interfering with mitochondrial activity although it can also suppress cell proliferation via other mechanisms. These results consistently support the hypothesis that mitochondrial targeting has therapeutic potential for MTC.

  18. Oral squamous cell carcinoma: survival, recurrence and death

    Antônio Camilo Souza Cruz

    2014-10-01

    Full Text Available This paper was based in data survey from macro and microscopic oral lesions characteristics, personal data and medical history of patients diagnosed with oral squamous cell carcinoma in the Lab of Pathological Anatomy from the Federal University of Alfenas from January 2000 to December 2010, establishing comparative parameters among clinical data, type of treatment, recurrence, survival and anatomic pathological characteristics of the lesions. Were analyzed the histopathological reports, dental and hospital records. The highest incidence was in white men, age between 50 and 60 years, married, with low education and socioeconomic levels. The beginning of treatment occurred in average 67 days after the histopathological diagnosis. The estimated survival of patients at five years was 42%. The consumption of alcohol and tobacco and the occurrence of metastasis were statistically significant for the increase of recurrence and lethality.

  19. Impact of starvation on survival, meat condition and metabolism of Chlamys farreri

    Yang, Hong-Sheng; Wang, Jian; Zhou, Yi; Wang, Ping; He, Yi-Chao; Zhang, Fu-Sui

    2001-03-01

    The effects of 60-day starvation on survival rate, condition index (CI), changes of nutrient composition of different tissues, respiration and excretion of scallop Chlamys farreri were studied in laboratory from Oct. 17 to Dec. 15, 1997. Two groups (control and starvation with 200 individuals each) were cultured in two 2 m3 tanks, with 31 to 32 salinity water at 17°C. Starvation effects were measured after 10, 20, 40 and 60 days. There was no mass mortality of scallops of the two tanks and survival rates of the control and starvation groups were 93.5% and 92.0%, respectively. Starvation had strong effect on the meat condition of the scallops, especially after 10 days; when relative lipid percentage dropped sharply while relative protein percentage increased. The impact of starvation on the oxygen consumption rate (OCR) and the ammonia-N excretion rate (AER) was obvious. The OCR increased rapidly after 10 days but decreased after 20 days. The AER increased after 10 days and 20 days, but decreased obviously from 20 to 40 days. The O∶N ratios varied to different degrees, and minimized after 20 days. The low O∶N ratios implied that the protein was the main material for the metabolism of C. farreri.

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

    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.

  1. SOLITARY CHEMORECEPTOR CELL SURVIVAL IS INDEPENDENT OF INTACT TRIGEMINAL INNERVATION

    Gulbransen, Brian; Silver, Wayne; Finger, Tom

    2008-01-01

    Nasal solitary chemoreceptor cells (SCCs) are a population of specialized chemosensory epithelial cells presumed to broaden trigeminal chemoreceptivity in mammals (Finger et al., 2003). SCCs are innervated by peptidergic trigeminal nerve fibers (Finger et al., 2003) but it is currently unknown if intact innervation is necessary for SCC development or survival. We tested the dependence of SCCs on innervation by eliminating trigeminal nerve fibers during development with neurogenin-1 knockout mice, during early postnatal development with capsaicin desensitization, and during adulthood with trigeminal lesioning. Our results demonstrate that elimination of innervation at any of these times does not result in decreased SCC numbers. In conclusion, neither SCC development nor mature cell maintenance is dependent on intact trigeminal innervation. PMID:18300260

  2. Romidepsin targets multiple survival signaling pathways in malignant T cells

    Valdez, B C; Brammer, J E; Li, Y; Murray, D; Liu, Y; Hosing, C; Nieto, Y; Champlin, R E; Andersson, B S

    2015-01-01

    Romidepsin is a cyclic molecule that inhibits histone deacetylases. It is Food and Drug Administration-approved for treatment of cutaneous and peripheral T-cell lymphoma, but its precise mechanism of action against malignant T cells is unknown. To better understand the biological effects of romidepsin in these cells, we exposed PEER and SUPT1 T-cell lines, and a primary sample from T-cell lymphoma patient (Patient J) to romidepsin. We then examined the consequences in some key oncogenic signaling pathways. Romidepsin displayed IC 50 values of 10.8, 7.9 and 7.0 nm in PEER, SUPT1 and Patient J cells, respectively. Strong inhibition of histone deacetylases and demethylases, increased production of reactive oxygen species and decreased mitochondrial membrane potential were observed, which may contribute to the observed DNA-damage response and apoptosis. The stress-activated protein kinase/c-Jun N-terminal kinase signaling pathway and unfolded protein response in the endoplasmic reticulum were activated, whereas the phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin (PI3K/AKT/mTOR) and β-catenin pro-survival pathways were inhibited. The decreased level of β-catenin correlated with the upregulation of its inhibitor SFRP1 through romidepsin-mediated hypomethylation of its gene promoter. Our results provide new insights into how romidepsin invokes malignant T-cell killing, show evidence of its associated DNA hypomethylating activity and offer a rationale for the development of romidepsin-containing combination therapies

  3. Models for cell survival with low LET radiation

    Payne, M.G.; Garrett, W.R.

    1975-01-01

    A model for cell survival under low LET irradiation was developed in which the cell is considered to have N 0 -independent sensitive sites, each of which can exist in either an undamaged state (state A) or one of two damaged states. Radiation can change the sensitive sites from the undamaged state to either of two damaged states. The first damaged state (state B) can either be repaired or be promoted on the second damaged state (state C), which is irreparable. The promotion from the first damaged state to the second can occur due to any of the following: (1) further radiation damage, (2) an abortive attempt to repair the site, or (3) the arrival at a part of the cell cycle where the damage is ''fixed.'' Subject to the further assumptions that radiation damage can occur either indirectly (i.e., through radiation products) or due to direct interaction, and that repair of the first damaged state is a one-step process, expressions can be derived for P(N/sub A/, N/sub B/,t) = probability that after time t a cell will have N/sub A/ sites in state A and N/sub B/ in state B. The problem of determining P(N/sub A/, N/sub B/, t) is formulated for arbitrary time dependences of the radiation field and of all rate coefficients. A large family of cell-survival models can be described by interpreting the sensitive sites in different ways and by making different choices of rate coefficients and of the combinations of numbers of sites in different states that will lead to cell death. (U.S.)

  4. Postirradiation DNA synthesis is inversely related to cell survival

    Kapiszewska, M.; Lange, C.S.

    1987-01-01

    Postirradiation (PI) events which might lead to cellular reproductive death or survival were studied in L5178Y-S (LY-S) cells. PI incubation at 25 0 C protects LY-S cells against the PLD fixation which takes place at 37 0 C. An optimal condition for the repair of PLD is 1h at 37 0 C followed by 4h holding at 25 0 C prior to the second half of a split dose, or 5L holding at 25 0 C without a 37 0 C incubation. Longer incubations at 37 0 C resulted in progressively decreased survivals. Postirradiation inhibition of DNA synthesis at 37 0 C was observed only during the first 30 min; thereafter, /sup 3/H-dThd incorporation was higher than in unirradiated controls. This excess synthesis effect was removed by shifting irradiated cells to 25 0 C holding. The inhibition observed at 25 0 C was reversed by shifting to 37 0 C. Thus the degree of postirradiation DNA synthesis is inversely related to PLD/SLD repair. DNA filter elution shows complete SSB repair by 3h at both temperatures (with faster kinetics at 37 0 C), and DSB repair plateaus at 80% (37 0 C) and 60% (25 0 C) after 90 min

  5. Effects of ultraviolet radiation on the survival and metabolic end products of Bacteroides melaninogenicus

    Smith-Kappus, S.D.

    1987-01-01

    In experiments investigating DNA repair, it was shown that B. melaninogenicus does not repair UV light induced damage via photoreactivation. Survival curves constructed for the organism after exposure to UV light at 254 nm and 365 nm under aerobic and anaerobic conditions while the organisms were in exponential or stationary growth phase, revealed that the cells were most sensitive to UV induced damage when exposed to radiation while in the exponential growth phase under aerobic conditions at either wavelength. B. melaninogenicus exposed to UV light under anaerobic conditions while the cells were in stationary growth phase were much more sensitive to UV induced damage at 254 nm than cells irradiated under the same conditions at 365 nm UV. Survival studies of B. melaninogenicus after co-insult with UV light and subinhibitory concentrations of chloramphenicol, metronidazole, caffeine, or fluoroacetate, at 254 nm UV or 365 nm UV, under aerobic and anaerobic atmospheric conditions illustrated a decreased shoulder region on the curves, particularly after 365 nm UV exposure, when compared to UV irradiation applied without subsequent chemical treatment

  6. Parameter resolution in two models for cell survival after radiation

    Di Cera, E.; Andreasi Bassi, F.; Arcovito, G.

    1989-01-01

    The resolvability of model parameters for the linear-quadratic and the repair-misrepair models for cell survival after radiation has been studied by Monte Carlo simulations as a function of the number of experimental data points collected in a given dose range and the experimental error. Statistical analysis of the results reveals the range of experimental conditions under which the model parameters can be resolved with sufficient accuracy, and points out some differences in the operational aspects of the two models. (orig.)

  7. A tryptophan derivative, ITE, enhances liver cell metabolic functions in vitro.

    Zhang, Xiaoqian; Lu, Juan; He, Bin; Tang, Lingling; Liu, Xiaoli; Zhu, Danhua; Cao, Hongcui; Wang, Yingjie; Li, Lanjuan

    2017-01-01

    Cell encapsulation provides a three-dimensional support by incorporating isolated cells into microcapsules with the goal of simultaneously maintaining cell survival and function, as well as providing active transport for a bioreactor in vitro similarly to that observed in vivo. However, the biotra-nsformation and metabolic functions of the encapsulated cells are not satisfactory for clinical applications. For this purpose, in this study, hepatoma-derived Huh7 cells/C3A cells were treated with 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), an endogenous non-toxic ligand for aryl hydrocarbon receptor, in monolayer cultures and on microspheres. The mRNA and protein levels, as well as the metabolic activities of drug metabolizing enzymes, albumin secretion and urea synthesis were determined. When the Huh7 and C3A cells cultured in a monolayer on two‑dimensional surfaces, ITE enhanced the protein levels and the metabolic activities of the major cytochrome P450 (CYP450) enzymes, CYP1A1, CYP1A2, CYP3A4 and CYP1B1, and slightly increased albumin secretion and urea synthesis. Moreover, when cultured on microspheres, ITE also substantially increased the protein levels and metabolic activities of CYP1A1, CYP1A2, CYP3A4 and CYP1B1 in both liver cell lines. On the whole, our findings indicate that ITE enhances the enzymatic activities of major CYP450 enzymes and the metabolic functions of liver cells cultured in monolayer or on microspheres, indicating that it may be utilized to improve the functions of hepatocytes. Thus, it may be used in the future for the treatment of liver diseases.

  8. A tryptophan derivative, ITE, enhances liver cell metabolic functions in vitro

    Zhang, Xiaoqian; Lu, Juan; He, Bin; Tang, Lingling; Liu, Xiaoli; Zhu, Danhua; Cao, Hongcui; Wang, Yingjie; Li, Lanjuan

    2017-01-01

    Cell encapsulation provides a three-dimensional support by incorporating isolated cells into microcapsules with the goal of simultaneously maintaining cell survival and function, as well as providing active transport for a bioreactor in vitro similarly to that observed in vivo. However, the biotransformation and metabolic functions of the encapsulated cells are not satisfactory for clinical applications. For this purpose, in this study, hepatoma-derived Huh7 cells/C3A cells were treated with 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), an endogenous non-toxic ligand for aryl hydrocarbon receptor, in monolayer cultures and on microspheres. The mRNA and protein levels, as well as the metabolic activities of drug metabolizing enzymes, albumin secretion and urea synthesis were determined. When the Huh7 and C3A cells cultured in a monolayer on two-dimensional surfaces, ITE enhanced the protein levels and the metabolic activities of the major cytochrome P450 (CYP450) enzymes, CYP1A1, CYP1A2, CYP3A4 and CYP1B1, and slightly increased albumin secretion and urea synthesis. Moreover, when cultured on microspheres, ITE also substantially increased the protein levels and metabolic activities of CYP1A1, CYP1A2, CYP3A4 and CYP1B1 in both liver cell lines. On the whole, our findings indicate that ITE enhances the enzymatic activities of major CYP450 enzymes and the metabolic functions of liver cells cultured in monolayer or on microspheres, indicating that it may be utilized to improve the functions of hepatocytes. Thus, it may be used in the future for the treatment of liver diseases. PMID:27959388

  9. Autophagy/Xenophagy as a survival strategy of cancer cells. The role of Cathepsins

    Malorni, W.; Matarrese, P.; Ascione, B.; Ciarlo, L.; Zakeri, Z.

    2009-01-01

    Macroautophagy, often referred as to autophagy (self-cannibalism), designates the genetically determined process by which portions of the cytoplasm, organelles and long-lived proteins are engulfed in double-membraned vacuoles (autophagosomes) and sent for lysosomal degradation. Basal levels of autophagy contribute to the maintenance of intracellular homoeostasis by ensuring the turnover of supernumerary, aged and/or damaged components. Under conditions of starvation, the autophagic pathway operates to supply cells with metabolic substrates, and thus represents an important pro-survival mechanism. In cultured cells, the withdrawal of growth factors, known to represent an experimental condition triggering autophagy, can also enhance xeno-cannibalism (xenophagy; xeno is from ancient greek=foreign)

  10. Metabolic cooperation between co-cultured lung cancer cells and lung fibroblasts.

    Koukourakis, Michael I; Kalamida, Dimitra; Mitrakas, Achilleas G; Liousia, Maria; Pouliliou, Stamatia; Sivridis, Efthimios; Giatromanolaki, Alexandra

    2017-11-01

    Cooperation of cancer cells with stromal cells, such as cancer-associated fibroblasts (CAFs), has been revealed as a mechanism sustaining cancer cell survival and growth. In the current study, we focus on the metabolic interactions of MRC5 lung fibroblasts with lung cancer cells (A549 and H1299) using co-culture experiments and studying changes of the metabolic protein expression profile and of their growth and migration abilities. Using western blotting, confocal microscopy and RT-PCR, we observed that in co-cultures MRC5 respond by upregulating pyruvate dehydrogenase (PDH) and the monocarboxylate transporter MCT1. In contrast, cancer cells increase the expression of glucose transporters (GLUT1), LDH5, PDH kinase and the levels of phosphorylated/inactivated pPDH. H1299 cells growing in the same culture medium with fibroblasts exhibit a 'metastasis-like' phenomenon by forming nests within the fibroblast area. LDH5 and pPDH were drastically upregulated in these nests. The growth rate of both MRC5 and cancer cells increased in co-cultures. Suppression of LDHA or PDK1 in cancer cells abrogates the stimulatory signal from cancer cells to fibroblasts. Incubation of MRC5 fibroblasts with lactate resulted in an increase of LDHB and of PDH expression. Silencing of PDH gene in fibroblasts, or silencing of PDK1 or LDHA gene in tumor cells, impedes cancer cell's migration ability. Overall, a metabolic cooperation between lung cancer cells and fibroblasts has been confirmed in the context of direct Warburg effect, thus the fibroblasts reinforce aerobic metabolism to support the intensified anaerobic glycolytic pathways exploited by cancer cells.

  11. Culture conditions affecting the survival response of Chinese hamster ovary cells treated by hyperthermia

    Highfield, D.P.; Holahan, E.V.; Dewey, W.C.

    1982-01-01

    Using lethally irradiated feeder cells to control cell population densities, researchers investigated the survival of Chinese hamster ovary cells heated between 42.2 and 45.5 degrees C. Test cells were plated into T25 flasks with or without feeder cells, incubated 2 hours at 37 degrees C, and then given various heat treatments. Under all heating conditions, survival increased in those flasks containing feeder cells. Increased survival (by as much as a factor of 100 for cells heated at 42.4 degrees C for 6-10 hr) was most apparent when cells were heated to thermotolerance. By adjustment of test and feeder cell numbers, survival increased as density increased; however, maximum survival followed a transition period that occurred between the plating of 1 X 10(4) and 6 X 10(4) cells. Experimental artifacts due to improper control of cell density was demonstrated

  12. ASSOSIATION BETWEEN PARAMETERS OF MINERAL BONE METABOLISM AND SURVIVAL IN PATIENTS UNDERGOING CHRONIC HEMODIALYSIS

    Branislav Apostolović

    2015-12-01

    Full Text Available Beside the traditional risk factors which have an effect on cardiovascular diseases, hemodialysis patients are exposed to metabolic factors, such as malnutrition, microinflammation and oxidative stress, along with mineral bone disorder. The aim of this study was to determine a three-year survival in patients undergoing chronic hemodialysis and to analyse correlation with parameters of mineral bone metabolism. During the three-year follow-up 186 patients were included, of which 115 men (61.83% and 71 women, with a mean age 61.47±12.42. The exact date and the direct cause of death were recorded and mineral bone metabolism parameters were analysed. Out of 67 dead patients, 33 (49.25% died from cardiovascular cause. Out of the total number of deaths in our study, only 11.9% of patients had a target PTH values. Patients with PTH>600 pg/ml are exposed to an increased risk from the overall mortality (RR=0.48, 95% CI (0.24-0.95, p=0.04, but also from cardiovascular mortality (RR=0.34, 95% CI (0.12-0.93, p=0.034 compared to patients with normal serum PTH. These patients have a statistically significant higher serum phosphorus in comparison with patients with normal PTH levels (1.72±0.42 vs. 1.39±0.36, p=0.032. Phosphorus above 2.10 mmol/L increases the relative risk for the overall mortality rate by 60% (RR=0.59, 95% CI (0.35-0.89, p=0.049. In our study, 2-fold higher risk of all-cause mortality (RR=2.00, 95% CI (0.92-4.36, p=0.048, and even 3-fold higher risk of cardiovascular mortality (RR=3.03, 95% CI (0.71-1.29, p=0.039 were found in patients with CaxP levels above 4.50 mmol2/L2. Three-year mortality rate of patients undergoing hemodialysis was 36.02%, while half of the patients died from cardiovascular disease. Patients with hyperparathyroidism and elevated calcium phosphorus product are at the highest risk, both for all-cause and cardiovascular mortality. Patients with hyperphosphatemia are at higher risk for all-cause mortality.

  13. Cell survival, cell death and cell cycle pathways are interconnected: Implications for cancer therapy

    Maddika, S; Ande, SR; Panigrahi, S

    2007-01-01

    )), and the Cip1/Waf1/Kip1-2-family (p21(Cip1/Waf1), p27(Kip1), p57(Kip2)) are shown both in the context of proliferation regulators and as contributors to the apoptotic machinery. Bcl2-family members (i.e. Bcl2, Bcl-X(L) Mcl-1(L); Bax, Bok/Mtd, Bak, and Bcl-X(S); Bad, Bid, Bim(EL), Bmf, Mcl-1(S)) are highlighted...... approaches that would involve redirecting over-active survival and proliferation pathways towards induction of apoptosis in cancer cells....

  14. Survival and kinetics of Chinese hamster ovary cell subpopulations induced by Adriamycin and radiation

    Schneiderman, M.H.

    1979-01-01

    Mitotic selection of Chinese hamster ovary (CHO) cells, at 10 min intervals after the initiation of Adriamycin and/or x-ray treatment was used to measure the kinetics and survival of cells which progressed without delay, the ''refractory'' cells, the cells that reached mitosis only after recovery from the treatment-induced delay, the ''recovered'' cells, and the survival of the cells remaining attached to the flask 5 h after treatment. The cell kinetics were determined from the rate at which cells entered mitosis, and the reproductive integrity from the survival of the selected refractory, recovered and remaining (unselected) cells

  15. Combined Treatment of MCF-7 Cells with AICAR and Methotrexate, Arrests Cell Cycle and Reverses Warburg Metabolism through AMP-Activated Protein Kinase (AMPK and FOXO1.

    Tamás Fodor

    Full Text Available Cancer cells are characterized by metabolic alterations, namely, depressed mitochondrial oxidation, enhanced glycolysis and pentose phosphate shunt flux to support rapid cell growth, which is called the Warburg effect. In our study we assessed the metabolic consequences of a joint treatment of MCF-7 breast cancer cells with AICAR, an inducer of AMP-activated kinase (AMPK jointly with methotrexate (MTX, a folate-analog antimetabolite that blunts de novo nucleotide synthesis. MCF7 cells, a model of breast cancer cells, were resistant to the individual application of AICAR or MTX, however combined treatment of AICAR and MTX reduced cell proliferation. Prolonged joint application of AICAR and MTX induced AMPK and consequently enhanced mitochondrial oxidation and reduced the rate of glycolysis. These metabolic changes suggest an anti-Warburg rearrangement of metabolism that led to the block of the G1/S and the G2/M transition slowing down cell cycle. The slowdown of cell proliferation was abolished when mitotropic transcription factors, PGC-1α, PGC-1β or FOXO1 were silenced. In human breast cancers higher expression of AMPKα and FOXO1 extended survival. AICAR and MTX exerts similar additive antiproliferative effect on other breast cancer cell lines, such as SKBR and 4T1 cells, too. Our data not only underline the importance of Warburg metabolism in breast cancer cells but nominate the AICAR+MTX combination as a potential cytostatic regime blunting Warburg metabolism. Furthermore, we suggest the targeting of AMPK and FOXO1 to combat breast cancer.

  16. Dysregulation of Iron Metabolism in Cholangiocarcinoma Stem-like Cells

    Raggi, Chiara; Gammella, Elena; Correnti, Margherita

    2017-01-01

    Cholangiocarcinoma (CCA) is a devastating liver tumour arising from malignant transformation of bile duct epithelial cells. Cancer stem cells (CSC) are a subset of tumour cells endowed with stem-like properties, which play a role in tumour initiation, recurrence and metastasis. In appropriate con...... compartment as a novel metabolic factor involved in CCA growth, may have implications for a better therapeutic approach....

  17. Vitamin K metabolism in Chinese Hamster Ovary cells

    Hoffman, H.S.

    1986-01-01

    Recent investigations suggest that vitamin K may have functions other than in blood coagulation and calcification. The present study was undertaken to investigate this hypothesis using cells in culture. Chinese Hamster Ovary (CHO) cells were chosen due to their active metabolism and growth and lack of similarity to liver and bone cells, in which vitamin K metabolism is well known. Cells were adapted to serum-free media, incubated in media containing the appropriate concentrations of vitamin K for specified times, scraped from plates, pelleted, extensively washed to remove adhering vitamin K, extracted with chloroform:methanol (2:1, v/v) and analyzed on C18 HPLC columns. Uptake of vitamin K by CHO cells follows saturation kinetics at vitamin K concentrations up to 25 μ M and is transported into cells at the rate of 10 pmol/min. 10 6 cells. After 24 hours, 3 H vitamin K is metabolized by CHO cells to several compounds, the major of which was isolated and identified as vitamin K epoxide. In 3 experiments, after 24 hours, the average cellular uptake of vitamin K was 8% with approximately half being metabolized to vitamin K epoxide. These results demonstrate that vitamin K is metabolized in cells with widely different functions and suggest a generalized function for vitamin K which has yet to be elucidated

  18. Ras and Rheb Signaling in Survival and Cell Death

    Ehrkamp, Anja; Herrmann, Christian; Stoll, Raphael; Heumann, Rolf

    2013-01-01

    One of the most obvious hallmarks of cancer is uncontrolled proliferation of cells partly due to independence of growth factor supply. A major component of mitogenic signaling is Ras, a small GTPase. It was the first identified human protooncogene and is known since more than three decades to promote cellular proliferation and growth. Ras was shown to support growth factor-independent survival during development and to protect from chemical or mechanical lesion-induced neuronal degeneration in postmitotic neurons. In contrast, for specific patho-physiological cases and cellular systems it has been shown that Ras may also promote cell death. Proteins from the Ras association family (Rassf, especially Rassf1 and Rassf5) are tumor suppressors that are activated by Ras-GTP, triggering apoptosis via e.g., activation of mammalian sterile 20-like (MST1) kinase. In contrast to Ras, their expression is suppressed in many types of tumours, which makes Rassf proteins an exciting model for understanding the divergent effects of Ras activity. It seems likely that the outcome of Ras signaling depends on the balance between the activation of its various downstream effectors, thus determining cellular fate towards either proliferation or apoptosis. Ras homologue enriched in brain (Rheb) is a protein from the Ras superfamily that is also known to promote proliferation, growth, and regeneration through the mammalian target of rapamycin (mTor) pathway. However, recent evidences indicate that the Rheb-mTor pathway may switch its function from a pro-growth into a cell death pathway, depending on the cellular situation. In contrast to Ras signaling, for Rheb, the cellular context is likely to modulate the whole Rheb-mTor pathway towards cellular death or survival, respectively

  19. Ras and Rheb Signaling in Survival and Cell Death

    Ehrkamp, Anja [Molecular Neurobiochemistry, Ruhr University of Bochum, 44780 Bochum (Germany); Herrmann, Christian [Department of Physical Chemistry1, Protein Interaction, Ruhr University of Bochum, 44780 Bochum (Germany); Stoll, Raphael [Biomolecular NMR, Ruhr University of Bochum, 44780 Bochum (Germany); Heumann, Rolf, E-mail: rolf.heumann@rub.de [Molecular Neurobiochemistry, Ruhr University of Bochum, 44780 Bochum (Germany)

    2013-05-28

    One of the most obvious hallmarks of cancer is uncontrolled proliferation of cells partly due to independence of growth factor supply. A major component of mitogenic signaling is Ras, a small GTPase. It was the first identified human protooncogene and is known since more than three decades to promote cellular proliferation and growth. Ras was shown to support growth factor-independent survival during development and to protect from chemical or mechanical lesion-induced neuronal degeneration in postmitotic neurons. In contrast, for specific patho-physiological cases and cellular systems it has been shown that Ras may also promote cell death. Proteins from the Ras association family (Rassf, especially Rassf1 and Rassf5) are tumor suppressors that are activated by Ras-GTP, triggering apoptosis via e.g., activation of mammalian sterile 20-like (MST1) kinase. In contrast to Ras, their expression is suppressed in many types of tumours, which makes Rassf proteins an exciting model for understanding the divergent effects of Ras activity. It seems likely that the outcome of Ras signaling depends on the balance between the activation of its various downstream effectors, thus determining cellular fate towards either proliferation or apoptosis. Ras homologue enriched in brain (Rheb) is a protein from the Ras superfamily that is also known to promote proliferation, growth, and regeneration through the mammalian target of rapamycin (mTor) pathway. However, recent evidences indicate that the Rheb-mTor pathway may switch its function from a pro-growth into a cell death pathway, depending on the cellular situation. In contrast to Ras signaling, for Rheb, the cellular context is likely to modulate the whole Rheb-mTor pathway towards cellular death or survival, respectively.

  20. Oxidative Stress, Redox Signaling, and Autophagy: Cell Death Versus Survival

    Navarro-Yepes, Juliana; Burns, Michaela; Anandhan, Annadurai; Khalimonchuk, Oleh; del Razo, Luz Maria; Quintanilla-Vega, Betzabet; Pappa, Aglaia; Panayiotidis, Mihalis I.

    2014-01-01

    Abstract Significance: The molecular machinery regulating autophagy has started becoming elucidated, and a number of studies have undertaken the task to determine the role of autophagy in cell fate determination within the context of human disease progression. Oxidative stress and redox signaling are also largely involved in the etiology of human diseases, where both survival and cell death signaling cascades have been reported to be modulated by reactive oxygen species (ROS) and reactive nitrogen species (RNS). Recent Advances: To date, there is a good understanding of the signaling events regulating autophagy, as well as the signaling processes by which alterations in redox homeostasis are transduced to the activation/regulation of signaling cascades. However, very little is known about the molecular events linking them to the regulation of autophagy. This lack of information has hampered the understanding of the role of oxidative stress and autophagy in human disease progression. Critical Issues: In this review, we will focus on (i) the molecular mechanism by which ROS/RNS generation, redox signaling, and/or oxidative stress/damage alter autophagic flux rates; (ii) the role of autophagy as a cell death process or survival mechanism in response to oxidative stress; and (iii) alternative mechanisms by which autophagy-related signaling regulate mitochondrial function and antioxidant response. Future Directions: Our research efforts should now focus on understanding the molecular basis of events by which autophagy is fine tuned by oxidation/reduction events. This knowledge will enable us to understand the mechanisms by which oxidative stress and autophagy regulate human diseases such as cancer and neurodegenerative disorders. Antioxid. Redox Signal. 21, 66–85. PMID:24483238

  1. Cell survival of human tumor cells compared with normal fibroblasts following 60Co gamma irradiation

    Lloyd, E.L.; Henning, C.B.; Reynolds, S.D.; Holmblad, G.L.; Trier, J.E.

    1982-01-01

    Three tumor cell lines, two of which were shown to be HeLa cells, were irradiated with 60 Co gamma irradiation, together with two cell cultures of normal human diploid fibroblasts. Cell survival was studied in three different experiments over a dose range of 2 to 14 gray. All the tumor cell lines showed a very wide shoulder in the dose response curves in contrast to the extremely narrow shoulder of the normal fibroblasts. In addition, the D/sub o/ values for the tumor cell lines were somewhat greater. These two characteristics of the dose response curves resulted in up to 2 orders of magnitude less sensitivity for cell inactivation of HeLa cells when compared with normal cells at high doses (10 gray). Because of these large differences, the extrapolation of results from the irradiation of HeLa cells concerning the mechanisms of normal cell killing should be interpreted with great caution

  2. Mammal survival at the Cretaceous-Palaeogene boundary: metabolic homeostasis in prolonged tropical hibernation in tenrecs.

    Lovegrove, Barry G; Lobban, Kerileigh D; Levesque, Danielle L

    2014-12-07

    Free-ranging common tenrecs, Tenrec ecaudatus, from sub-tropical Madagascar, displayed long-term (nine months) hibernation which lacked any evidence of periodic interbout arousals (IBAs). IBAs are the dominant feature of the mammalian hibernation phenotype and are thought to periodically restore long-term ischaemia damage and/or metabolic imbalances (depletions and accumulations). However, the lack of IBAs in tenrecs suggests no such pathology at hibernation Tbs > 22°C. The long period of tropical hibernation that we report might explain how the ancestral placental mammal survived the global devastation that drove the dinosaurs and many other vertebrates to extinction at the Cretaceous-Palaeogene boundary following a meteorite impact. The genetics and biochemistry of IBAs are of immense interest to biomedical researchers and space exploration scientists, in the latter case, those envisioning a hibernating state in astronauts for deep space travel. Unravelling the physiological thresholds and temperature dependence of IBAs will provide new impetus to these research quests. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  3. Mammal survival at the Cretaceous–Palaeogene boundary: metabolic homeostasis in prolonged tropical hibernation in tenrecs

    Lovegrove, Barry G.; Lobban, Kerileigh D.; Levesque, Danielle L.

    2014-01-01

    Free-ranging common tenrecs, Tenrec ecaudatus, from sub-tropical Madagascar, displayed long-term (nine months) hibernation which lacked any evidence of periodic interbout arousals (IBAs). IBAs are the dominant feature of the mammalian hibernation phenotype and are thought to periodically restore long-term ischaemia damage and/or metabolic imbalances (depletions and accumulations). However, the lack of IBAs in tenrecs suggests no such pathology at hibernation Tbs > 22°C. The long period of tropical hibernation that we report might explain how the ancestral placental mammal survived the global devastation that drove the dinosaurs and many other vertebrates to extinction at the Cretaceous–Palaeogene boundary following a meteorite impact. The genetics and biochemistry of IBAs are of immense interest to biomedical researchers and space exploration scientists, in the latter case, those envisioning a hibernating state in astronauts for deep space travel. Unravelling the physiological thresholds and temperature dependence of IBAs will provide new impetus to these research quests. PMID:25339721

  4. The Concerted Action of Type 2 and Type 3 Deiodinases Regulates the Cell Cycle and Survival of Basal Cell Carcinoma Cells.

    Miro, Caterina; Ambrosio, Raffaele; De Stefano, Maria Angela; Di Girolamo, Daniela; Di Cicco, Emery; Cicatiello, Annunziata Gaetana; Mancino, Giuseppina; Porcelli, Tommaso; Raia, Maddalena; Del Vecchio, Luigi; Salvatore, Domenico; Dentice, Monica

    2017-04-01

    Thyroid hormones (THs) mediate pleiotropic cellular processes involved in metabolism, cellular proliferation, and differentiation. The intracellular hormonal environment can be tailored by the type 1 and 2 deiodinase enzymes D2 and D3, which catalyze TH activation and inactivation respectively. In many cellular systems, THs exert well-documented stimulatory or inhibitory effects on cell proliferation; however, the molecular mechanisms by which they control rates of cell cycle progression have not yet been entirely clarified. We previously showed that D3 depletion or TH treatment influences the proliferation and survival of basal cell carcinoma (BCC) cells. Surprisingly, we also found that BCC cells express not only sustained levels of D3 but also robust levels of D2. The aim of the present study was to dissect the contribution of D2 to TH metabolism in the BCC context, and to identify the molecular changes associated with cell proliferation and survival induced by TH and mediated by D2 and D3. We used the CRISPR/Cas9 technology to genetically deplete D2 and D3 in BCC cells and studied the consequences of depletion on cell cycle progression and on cell death. Cell cycle progression was analyzed by fluorescence activated cell sorting analysis of synchronized cells, and the apoptosis rate by annexin V incorporation. Mechanistic investigations revealed that D2 inactivation accelerates cell cycle progression thereby enhancing the proportion of S-phase cells and cyclin D1 expression. Conversely, D3 mutagenesis drastically suppressed cell proliferation and enhanced apoptosis of BCC cells. Furthermore, the basal apoptotic rate was oppositely regulated in D2- and D3-depleted cells. Our results indicate that BCC cells constitute an example in which the TH signal is finely tuned by the concerted expression of opposite-acting deiodinases. The dual regulation of D2 and D3 expression plays a critical role in cell cycle progression and cell death by influencing cyclin D1-mediated

  5. Metabolic rate determines haematopoietic stem cell self-renewal.

    Sastry, P S R K

    2004-01-01

    The number of haematopoietic stem cells (HSCs) per animal is conserved across species. This means the HSCs need to maintain hematopoiesis over a longer period in larger animals. This would result in the requirement of stem cell self-renewal. At present the three existing models are the stochastic model, instructive model and the third more recently proposed is the chiaro-scuro model. It is a well known allometric law that metabolic rate scales to the three quarter power. Larger animals have a lower metabolic rate, compared to smaller animals. Here it is being hypothesized that metabolic rate determines haematopoietic stem cell self-renewal. At lower metabolic rate the stem cells commit for self-renewal, where as at higher metabolic rate they become committed to different lineages. The present hypothesis can explain the salient features of the different models. Recent findings regarding stem cell self-renewal suggest an important role for Wnt proteins and their receptors known as frizzleds, which are an important component of cell signaling pathway. The role of cGMP in the Wnts action provides further justification for the present hypothesis as cGMP is intricately linked to metabolic rate. One can also explain the telomere homeostasis by the present hypothesis. One prediction of the present hypothesis is with reference to the limit of cell divisions known as Hayflick limit, here it is being suggested that this is the result of metabolic rate in laboratory conditions and there can be higher number of cell divisions in vivo if the metabolic rate is lower. Copyright 2004 Elsevier Ltd.

  6. Characterization of the metabolic phenotype of rapamycin-treated CD8+ T cells with augmented ability to generate long-lasting memory cells.

    Shan He

    Full Text Available BACKGROUND: Cellular metabolism plays a critical role in regulating T cell responses and the development of memory T cells with long-term protections. However, the metabolic phenotype of antigen-activated T cells that are responsible for the generation of long-lived memory cells has not been characterized. DESIGN AND METHODS: Using lymphocytic choriomeningitis virus (LCMV peptide gp33-specific CD8(+ T cells derived from T cell receptor transgenic mice, we characterized the metabolic phenotype of proliferating T cells that were activated and expanded in vitro in the presence or absence of rapamycin, and determined the capability of these rapamycin-treated T cells to generate long-lived memory cells in vivo. RESULTS: Antigen-activated CD8(+ T cells treated with rapamycin gave rise to 5-fold more long-lived memory T cells in vivo than untreated control T cells. In contrast to that control T cells only increased glycolysis, rapamycin-treated T cells upregulated both glycolysis and oxidative phosphorylation (OXPHOS. These rapamycin-treated T cells had greater ability than control T cells to survive withdrawal of either glucose or growth factors. Inhibition of OXPHOS by oligomycin significantly reduced the ability of rapamycin-treated T cells to survive growth factor withdrawal. This effect of OXPHOS inhibition was accompanied with mitochondrial hyperpolarization and elevation of reactive oxygen species that are known to be toxic to cells. CONCLUSIONS: Our findings indicate that these rapamycin-treated T cells may represent a unique cell model for identifying nutrients and signals critical to regulating metabolism in both effector and memory T cells, and for the development of new methods to improve the efficacy of adoptive T cell cancer therapy.

  7. Induced Pluripotent Stem Cell-Derived Neural Cells Survive and Mature in the Nonhuman Primate Brain

    Marina E. Emborg

    2013-03-01

    Full Text Available The generation of induced pluripotent stem cells (iPSCs opens up the possibility for personalized cell therapy. Here, we show that transplanted autologous rhesus monkey iPSC-derived neural progenitors survive for up to 6 months and differentiate into neurons, astrocytes, and myelinating oligodendrocytes in the brains of MPTP-induced hemiparkinsonian rhesus monkeys with a minimal presence of inflammatory cells and reactive glia. This finding represents a significant step toward personalized regenerative therapies.

  8. Effects of UV-B irradiation on growth, survival, pigmentation and nitrogen metabolism enzymes in Cyanobacteria

    Sinha, R.P.; Hader, D.P. [Institut fuer Botanik und Pharmazeutische Biologie, Friedrich-Alexander Universitaet, Erlangen (Germany); Kumar, H.D.; Kumar, A. [Banaras Hindu University, Varanasi (India)

    1995-12-31

    The effects of artificial UV-B irradiation on growth, survival, pigmentation, nitrate reductase (NR), glutamine synthetase (GS) and total protein profile have been studied in a number of N{sub 2}-fixing cyanobacterial strains isolated from rice (paddy) fields in India. Different organisms show different effects in terms of growth and survival. Complete killing of Anabaena sp. and Nostoc carmium occurs after 120 min of UV-B exposure, whereas the same occurs only after 150 min of exposure in the case of Nostoc commune and Scytonema sp. Growth patterns of the cells treated with UV-B revealed that Nostoc commune and Scytonema sp. are comparatively more tolerant than Anabaena sp. and Nostoc carmium. Pigment content, particularly phycocyanin, was severely decreased following UV-B irradiation in all strains tested so far. In vivo NR activity was found to increase, while in vivo GS activity was decreased following exposure to UV-B for different durations in all test organisms; although complete inhibition of GS activity did not occur even after 120 min of UV-B exposure. (author). 37 refs, 6 figs.

  9. Effects of UV-B irradiation on growth, survival, pigmentation and nitrogen metabolism enzymes in Cyanobacteria

    Sinha, R.P.; Hader, D.P.; Kumar, H.D.; Kumar, A.

    1995-01-01

    The effects of artificial UV-B irradiation on growth, survival, pigmentation, nitrate reductase (NR), glutamine synthetase (GS) and total protein profile have been studied in a number of N 2 -fixing cyanobacterial strains isolated from rice (paddy) fields in India. Different organisms show different effects in terms of growth and survival. Complete killing of Anabaena sp. and Nostoc carmium occurs after 120 min of UV-B exposure, whereas the same occurs only after 150 min of exposure in the case of Nostoc commune and Scytonema sp. Growth patterns of the cells treated with UV-B revealed that Nostoc commune and Scytonema sp. are comparatively more tolerant than Anabaena sp. and Nostoc carmium. Pigment content, particularly phycocyanin, was severely decreased following UV-B irradiation in all strains tested so far. In vivo NR activity was found to increase, while in vivo GS activity was decreased following exposure to UV-B for different durations in all test organisms; although complete inhibition of GS activity did not occur even after 120 min of UV-B exposure. (author)

  10. Mitochondrial metabolism in hematopoietic stem cells requires functional FOXO3

    Rimmelé, Pauline; Liang, Raymond; Bigarella, Carolina L; Kocabas, Fatih; Xie, Jingjing; Serasinghe, Madhavika N; Chipuk, Jerry; Sadek, Hesham; Zhang, Cheng Cheng; Ghaffari, Saghi

    2015-01-01

    Hematopoietic stem cells (HSC) are primarily dormant but have the potential to become highly active on demand to reconstitute blood. This requires a swift metabolic switch from glycolysis to mitochondrial oxidative phosphorylation. Maintenance of low levels of reactive oxygen species (ROS), a by-product of mitochondrial metabolism, is also necessary for sustaining HSC dormancy. Little is known about mechanisms that integrate energy metabolism with hematopoietic stem cell homeostasis. Here, we identify the transcription factor FOXO3 as a new regulator of metabolic adaptation of HSC. ROS are elevated in Foxo3−/− HSC that are defective in their activity. We show that Foxo3−/− HSC are impaired in mitochondrial metabolism independent of ROS levels. These defects are associated with altered expression of mitochondrial/metabolic genes in Foxo3−/− hematopoietic stem and progenitor cells (HSPC). We further show that defects of Foxo3−/− HSC long-term repopulation activity are independent of ROS or mTOR signaling. Our results point to FOXO3 as a potential node that couples mitochondrial metabolism with HSC homeostasis. These findings have critical implications for mechanisms that promote malignant transformation and aging of blood stem and progenitor cells. PMID:26209246

  11. Selection of metastatic breast cancer cells based on adaptability of their metabolic state.

    Balraj Singh

    Full Text Available A small subpopulation of highly adaptable breast cancer cells within a vastly heterogeneous population drives cancer metastasis. Here we describe a function-based strategy for selecting rare cancer cells that are highly adaptable and drive malignancy. Although cancer cells are dependent on certain nutrients, e.g., glucose and glutamine, we hypothesized that the adaptable cancer cells that drive malignancy must possess an adaptable metabolic state and that such cells could be identified using a robust selection strategy. As expected, more than 99.99% of cells died upon glutamine withdrawal from the aggressive breast cancer cell line SUM149. The rare cells that survived and proliferated without glutamine were highly adaptable, as judged by additional robust adaptability assays involving prolonged cell culture without glucose or serum. We were successful in isolating rare metabolically plastic glutamine-independent (Gln-ind variants from several aggressive breast cancer cell lines that we tested. The Gln-ind cells overexpressed cyclooxygenase-2, an indicator of tumor aggressiveness, and they were able to adjust their glutaminase level to suit glutamine availability. The Gln-ind cells were anchorage-independent, resistant to chemotherapeutic drugs doxorubicin and paclitaxel, and resistant to a high concentration of a COX-2 inhibitor celecoxib. The number of cells being able to adapt to non-availability of glutamine increased upon prior selection of cells for resistance to chemotherapy drugs or resistance to celecoxib, further supporting a linkage between cellular adaptability and therapeutic resistance. Gln-ind cells showed indications of oxidative stress, and they produced cadherin11 and vimentin, indicators of mesenchymal phenotype. Gln-ind cells were more tumorigenic and more metastatic in nude mice than the parental cell line as judged by incidence and time of occurrence. As we decreased the number of cancer cells in xenografts, lung metastasis

  12. Selection of Metastatic Breast Cancer Cells Based on Adaptability of Their Metabolic State

    Singh, Balraj; Tai, Karen; Madan, Simran; Raythatha, Milan R.; Cady, Amanda M.; Braunlin, Megan; Irving, LaTashia R.; Bajaj, Ankur; Lucci, Anthony

    2012-01-01

    A small subpopulation of highly adaptable breast cancer cells within a vastly heterogeneous population drives cancer metastasis. Here we describe a function-based strategy for selecting rare cancer cells that are highly adaptable and drive malignancy. Although cancer cells are dependent on certain nutrients, e.g., glucose and glutamine, we hypothesized that the adaptable cancer cells that drive malignancy must possess an adaptable metabolic state and that such cells could be identified using a robust selection strategy. As expected, more than 99.99% of cells died upon glutamine withdrawal from the aggressive breast cancer cell line SUM149. The rare cells that survived and proliferated without glutamine were highly adaptable, as judged by additional robust adaptability assays involving prolonged cell culture without glucose or serum. We were successful in isolating rare metabolically plastic glutamine-independent (Gln-ind) variants from several aggressive breast cancer cell lines that we tested. The Gln-ind cells overexpressed cyclooxygenase-2, an indicator of tumor aggressiveness, and they were able to adjust their glutaminase level to suit glutamine availability. The Gln-ind cells were anchorage-independent, resistant to chemotherapeutic drugs doxorubicin and paclitaxel, and resistant to a high concentration of a COX-2 inhibitor celecoxib. The number of cells being able to adapt to non-availability of glutamine increased upon prior selection of cells for resistance to chemotherapy drugs or resistance to celecoxib, further supporting a linkage between cellular adaptability and therapeutic resistance. Gln-ind cells showed indications of oxidative stress, and they produced cadherin11 and vimentin, indicators of mesenchymal phenotype. Gln-ind cells were more tumorigenic and more metastatic in nude mice than the parental cell line as judged by incidence and time of occurrence. As we decreased the number of cancer cells in xenografts, lung metastasis and then primary

  13. Survival curves and cell restoration of gamma irradiated chlorella

    Gilet, Roland

    1970-01-01

    The characteristics of the living material used and the cultures developed are defined. The irradiation techniques and the dosimetry methods used are described. The clonal growth in a gelified nutrient solution was studied and the survival curves, which are very reproducible when anoxic conditions are eliminated, were established. It is shown that the radiosensitivity of Chlorella decreases with the age of the culture when the plateau of the growth curve is reached, and that for synchronous cells it varies slightly with the phase in the cycle at which the radiation is received. The restoration from sublethal damage occurs quickly and does not depend upon the continuation of the cell cycle when no multiplication occurs during the experiments and is not modified by anoxic conditions. The restoration rate is reduced at 0 deg. C. It explains the variations in the apparent radiosensitivity with the dose rate. In contrast with the results published for many cells, the restoration is incomplete. The problem of the elimination of sublethal damage during clonal development is posed. A model summarizing the experimental results and suggesting future work is given. (author) [fr

  14. Survival of red blood cells after transfusion: processes and consequences

    Giel eBosman

    2013-12-01

    Full Text Available The currently available data suggest that efforts towards improving the quality of red blood cell (RBC blood bank products should concentrate on: (1 preventing the removal of a considerable fraction of the transfused RBCs that takes place within the first hours after transfusion; (2 minimizing the interaction of the transfused RBCs with the patient's immune system. These issues are important in reducing the number and extent of the damaging side effects of transfusions, such as generation of alloantibodies and autoantibodies and iron accumulation, especially in transfusion-dependent patients. Thus, it becomes important for blood bank research not only to assess the classical RBC parameters for quality control during storage, but even more so to identify the parameters that predict RBC survival, function and behaviour in the patient after transfusion. These parameters are likely to result from elucidation of the mechanisms that underly physiological RBC aging in vivo, and that lead to the generation of senescent cell antigens and the accumulation of damaged molecules in vesicles. Also, study of RBC pathology-related mechanisms, such as encountered in various hemoglobinopathies and membranopathies, may help to elucidate the mechanisms underlying a storage-associated increase in susceptibility to physiological stress conditions. Recent data indicate that a combination of new approaches in vitro to mimick RBC behaviour in vivo, the growing knowledge of the signaling networks that regulate RBC structure and function, and the rapidly expanding set of proteomic and metabolomic data, will be instrumental to identify the storage-associated processes that control RBC survival after transfusion.

  15. Cell-selective metabolic labeling of biomolecules with bioorthogonal functionalities.

    Xie, Ran; Hong, Senlian; Chen, Xing

    2013-10-01

    Metabolic labeling of biomolecules with bioorthogonal functionalities enables visualization, enrichment, and analysis of the biomolecules of interest in their physiological environments. This versatile strategy has found utility in probing various classes of biomolecules in a broad range of biological processes. On the other hand, metabolic labeling is nonselective with respect to cell type, which imposes limitations for studies performed in complex biological systems. Herein, we review the recent methodological developments aiming to endow metabolic labeling strategies with cell-type selectivity. The cell-selective metabolic labeling strategies have emerged from protein and glycan labeling. We envision that these strategies can be readily extended to labeling of other classes of biomolecules. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. New paradigms for metabolic modeling of human cells

    Mardinoglu, Adil; Nielsen, Jens

    2015-01-01

    review recent work on reconstruction of GEMs for human cell/tissue types and cancer, and the use of GEMs for identification of metabolic changes occurring in response to disease development. We further discuss how GEMs can be used for the development of efficient therapeutic strategies. Finally......, challenges in integration of cell/tissue models for simulation of whole body functions as well as integration of GEMs with other biological networks for generating complete cell/tissue models are presented.......Abnormalities in cellular functions are associated with the progression of human diseases, often resulting in metabolic reprogramming. GEnome-scale metabolic Models (GEMs) have enabled studying global metabolic reprogramming in connection with disease development in a systematic manner. Here we...

  17. SIRT1 regulates MAPK pathways in vitiligo skin: insight into the molecular pathways of cell survival

    Becatti, Matteo; Fiorillo, Claudia; Barygina, Victoria; Cecchi, Cristina; Lotti, Torello; Prignano, Francesca; Silvestro, Agrippino; Nassi, Paolo; Taddei, Niccolò

    2014-01-01

    Vitiligo is an acquired and progressive hypomelanotic disease that manifests as circumscribed depigmented patches on the skin. The aetiology of vitiligo remains unclear, but recent experimental data underline the interactions between melanocytes and other typical skin cells, particularly keratinocytes. Our previous results indicate that keratinocytes from perilesional skin show the features of damaged cells. Sirtuins (silent mating type information regulation 2 homolog) 1, well-known modulators of lifespan in many species, have a role in gene repression, metabolic control, apoptosis and cell survival, DNA repair, development, inflammation, neuroprotection and healthy ageing. In the literature there is no evidence for SIRT1 signalling in vitiligo and its possible involvement in disease progression. Here, biopsies were taken from the perilesional skin of 16 patients suffering from non-segmental vitiligo and SIRT1 signalling was investigated in these cells. For the first time, a new SIRT1/Akt, also known as Protein Kinase B (PKB)/mitogen-activated protein kinase (MAPK) signalling has been revealed in vitiligo. SIRT1 regulates MAPK pathway via Akt-apoptosis signal-regulating kinase-1 and down-regulates pro-apoptotic molecules, leading to decreased oxidative stress and apoptotic cell death in perilesional vitiligo keratinocytes. We therefore propose SIRT1 activation as a novel way of protecting perilesional vitiligo keratinocytes from damage. PMID:24410795

  18. Snail regulates cell survival and inhibits cellular senescence in human metastatic prostate cancer cell lines.

    Emadi Baygi, Modjtaba; Soheili, Zahra Soheila; Schmitz, Ingo; Sameie, Shahram; Schulz, Wolfgang A

    2010-12-01

    The epithelial-mesenchymal transition (EMT) is regarded as an important step in cancer metastasis. Snail, a master regulator of EMT, has been recently proposed to act additionally as a cell survival factor and inducer of motility. We have investigated the function of Snail (SNAI1) in prostate cancer cells by downregulating its expression via short (21-mer) interfering RNA (siRNA) and measuring the consequences on EMT markers, cell viability, death, cell cycle, senescence, attachment, and invasivity. Of eight carcinoma cell lines, the prostate carcinoma cell lines LNCaP and PC-3 showed the highest and moderate expression of SNAI1 mRNA, respectively, as measured by quantitative RT-PCR. Long-term knockdown of Snail induced a severe decline in cell numbers in LNCaP and PC-3 and caspase activity was accordingly enhanced in both cell lines. In addition, suppression of Snail expression induced senescence in LNCaP cells. SNAI1-siRNA-treated cells did not tolerate detachment from the extracellular matrix, probably due to downregulation of integrin α6. Expression of E-cadherin, vimentin, and fibronectin was also affected. Invasiveness of PC-3 cells was not significantly diminished by Snail knockdown. Our data suggest that Snail acts primarily as a survival factor and inhibitor of cellular senescence in prostate cancer cell lines. We therefore propose that Snail can act as early driver of prostate cancer progression.

  19. Metabolic Regulation of a Bacterial Cell System with Emphasis on Escherichia coli Metabolism

    Shimizu, Kazuyuki

    2013-01-01

    It is quite important to understand the overall metabolic regulation mechanism of bacterial cells such as Escherichia coli from both science (such as biochemistry) and engineering (such as metabolic engineering) points of view. Here, an attempt was made to clarify the overall metabolic regulation mechanism by focusing on the roles of global regulators which detect the culture or growth condition and manipulate a set of metabolic pathways by modulating the related gene expressions. For this, it was considered how the cell responds to a variety of culture environments such as carbon (catabolite regulation), nitrogen, and phosphate limitations, as well as the effects of oxygen level, pH (acid shock), temperature (heat shock), and nutrient starvation. PMID:25937963

  20. Genetic modification of embryonic stem cells with VEGF enhances cell survival and improves cardiac function.

    Xie, Xiaoyan; Cao, Feng; Sheikh, Ahmad Y; Li, Zongjin; Connolly, Andrew J; Pei, Xuetao; Li, Ren-Ke; Robbins, Robert C; Wu, Joseph C

    2007-01-01

    Cardiac stem cell therapy remains hampered by acute donor cell death posttransplantation and the lack of reliable methods for tracking cell survival in vivo. We hypothesize that cells transfected with inducible vascular endothelial growth factor 165 (VEGF(165)) can improve their survival as monitored by novel molecular imaging techniques. Mouse embryonic stem (ES) cells were transfected with an inducible, bidirectional tetracycline (Bi-Tet) promoter driving VEGF(165) and renilla luciferase (Rluc). Addition of doxycycline induced Bi-Tet expression of VEGF(165) and Rluc significantly compared to baseline (p<0.05). Expression of VEGF(165) enhanced ES cell proliferation and inhibited apoptosis as determined by Annexin-V staining. For noninvasive imaging, ES cells were transduced with a double fusion (DF) reporter gene consisting of firefly luciferase and enhanced green fluorescence protein (Fluc-eGFP). There was a robust correlation between cell number and Fluc activity (R(2)=0.99). Analysis by immunostaining, histology, and RT-PCR confirmed that expression of Bi-Tet and DF systems did not affect ES cell self-renewal or pluripotency. ES cells were differentiated into beating embryoid bodies expressing cardiac markers such as troponin, Nkx2.5, and beta-MHC. Afterward, 5 x 10(5) cells obtained from these beating embryoid bodies or saline were injected into the myocardium of SV129 mice (n=36) following ligation of the left anterior descending (LAD) artery. Bioluminescence imaging (BLI) and echocardiography showed that VEGF(165) induction led to significant improvements in both transplanted cell survival and cardiac function (p<0.05). This is the first study to demonstrate imaging of embryonic stem cell-mediated gene therapy targeting cardiovascular disease. With further validation, this platform may have broad applications for current basic research and further clinical studies.

  1. Crassulacean Acid Metabolism Permutation and Survival of Caralluma Species (Apocynaceae in Arid Habitats

    Yahya S. Masrahi

    2012-07-01

    Full Text Available Several species of the stem succulent Caralluma (Apocynaceae are abundant perennials in arid regions of the Arabian Peninsula. These arid regions have a short wet season with erratic rainfall and are characterized by harsh climatic conditions of high temperature, high evaporation and sand storms. Work presented in this paper aimed at investigating importance of Crassulacean Acid Metabolism (CAM for survival of three Caralluma species in their natural habitat. Investigations involved studying stomatal characteristics, stomatal diffusive conductance, chlorophyll fluorescence, and CAM in three species of Caralluma, namely C. acutangula (Decne. N.E.Br., C. edulis (Edgew. Benth. ex Hook.f., and C. subulata (Forssk. Decne. Microscopic examination revealed a pattern of stomatal characteristics typical of CAM plants in these three Caralluma species. Results showed that these three Caralluma species were obligate CAM plants exhibiting this mode of photosynthesis during both the wet and the dry seasons. Under protracted water stress during the long dry season very low values of stomatal diffusive conductance and dampening of CAM acidification-deacidification cycles denoted the tendency of these three Caralluma species to shift from the obligate CAM physiotype to CAM-idling mode. Chlorophyll fluorescence measurements indicated that protracted water stress induced a reduction in Photosystem II (PSII antenna efficiency and quantum yield in the three studied Caralluma species. This reduction of PSII activity occurred in concomitance with a marked rise in non-photochemical quenching of chlorophyll fluorescence denoting operation of non-photochemical energy dissipating mechanisms known to be important for photoprotection of the photosynthetic apparatus.

  2. Pluripotent Stem Cell Metabolism and Mitochondria: Beyond ATP

    Jarmon G. Lees

    2017-01-01

    Full Text Available Metabolism is central to embryonic stem cell (ESC pluripotency and differentiation, with distinct profiles apparent under different nutrient milieu, and conditions that maintain alternate cell states. The significance of altered nutrient availability, particularly oxygen, and metabolic pathway activity has been highlighted by extensive studies of their impact on preimplantation embryo development, physiology, and viability. ESC similarly modulate their metabolism in response to altered metabolite levels, with changes in nutrient availability shown to have a lasting impact on derived cell identity through the regulation of the epigenetic landscape. Further, the preferential use of glucose and anaplerotic glutamine metabolism serves to not only support cell growth and proliferation but also minimise reactive oxygen species production. However, the perinuclear localisation of spherical, electron-poor mitochondria in ESC is proposed to sustain ESC nuclear-mitochondrial crosstalk and a mitochondrial-H2O2 presence, to facilitate signalling to support self-renewal through the stabilisation of HIFα, a process that may be favoured under physiological oxygen. The environment in which a cell is grown is therefore a critical regulator and determinant of cell fate, with metabolism, and particularly mitochondria, acting as an interface between the environment and the epigenome.

  3. Glucose metabolism regulates T cell activation, differentiation and functions

    Clovis Steve Palmer

    2015-01-01

    Full Text Available The adaptive immune system is equipped to eliminate both tumors and pathogenic microorganisms. It requires a series of complex and coordinated signals to drive the activation, proliferation and differentiation of appropriate T cell subsets. It is now established that changes in cellular activation are coupled to profound changes in cellular metabolism. In addition, emerging evidence now suggest that specific metabolic alterations associated with distinct T cell subsets may be ancillary to their differentiation and influential in their immune functions. The Warburg effect originally used to describe a phenomenon in which most cancer cells relied on aerobic glycolysis for their growth is a key process that sustain T cell activation and differentiation. Here we review how different aspects of metabolism in T cells influence their functions, focusing on the emerging role of key regulators of glucose metabolism such as HIF-1α. A thorough understanding of the role of metabolism in T cell function could provide insights into mechanisms involved in inflammatory-mediated conditions, with the potential for developing novel therapeutic approaches to treat these diseases.

  4. Repurposing Lesogaberan to Promote Human Islet Cell Survival and β-Cell Replication

    Jide Tian

    2017-01-01

    Full Text Available The activation of β-cell’s A- and B-type gamma-aminobutyric acid receptors (GABAA-Rs and GABAB-Rs can promote their survival and replication, and the activation of α-cell GABAA-Rs promotes their conversion into β-cells. However, GABA and the most clinically applicable GABA-R ligands may be suboptimal for the long-term treatment of diabetes due to their pharmacological properties or potential side-effects on the central nervous system (CNS. Lesogaberan (AZD3355 is a peripherally restricted high-affinity GABAB-R-specific agonist, originally developed for the treatment of gastroesophageal reflux disease (GERD that appears to be safe for human use. This study tested the hypothesis that lesogaberan could be repurposed to promote human islet cell survival and β-cell replication. Treatment with lesogaberan significantly enhanced replication of human islet cells in vitro, which was abrogated by a GABAB-R antagonist. Immunohistochemical analysis of human islets that were grafted into immune-deficient mice revealed that oral treatment with lesogaberan promoted human β-cell replication and islet cell survival in vivo as effectively as GABA (which activates both GABAA-Rs and GABAB-Rs, perhaps because of its more favorable pharmacokinetics. Lesogaberan may be a promising drug candidate for clinical studies of diabetes intervention and islet transplantation.

  5. Collagen esterification enhances the function and survival of pancreatic β cells in 2D and 3D culture systems

    Ko, Jae Hyung [Regenerative Medicine Research Center, Dalim Tissen Co., LTD., 383-93, Yonnam-Dong, Mapo-gu, Seoul (Korea, Republic of); Kim, Yang Hee [Regenerative Medicine Research Center, Dalim Tissen Co., LTD., 383-93, Yonnam-Dong, Mapo-gu, Seoul (Korea, Republic of); Asan Institute for Life Science, 388-1 Pungnap-2 Dong, Songpa-gu, Seoul (Korea, Republic of); Jeong, Seong Hee; Lee, Song [Asan Institute for Life Science, 388-1 Pungnap-2 Dong, Songpa-gu, Seoul (Korea, Republic of); Park, Si-Nae [Regenerative Medicine Research Center, Dalim Tissen Co., LTD., 383-93, Yonnam-Dong, Mapo-gu, Seoul (Korea, Republic of); Shim, In Kyong, E-mail: shimiink@gmail.com [Asan Institute for Life Science, 388-1 Pungnap-2 Dong, Songpa-gu, Seoul (Korea, Republic of); Kim, Song Cheol, E-mail: drksc@amc.seoul.kr [Asan Institute for Life Science, 388-1 Pungnap-2 Dong, Songpa-gu, Seoul (Korea, Republic of); Department of Surgery, University of Ulsan College of Medicine & Asan Medical Center, 388-1 Pungnap-2 Dong, Songpa-gu, Seoul (Korea, Republic of)

    2015-08-07

    Collagen, one of the most important components of the extracellular matrix (ECM), may play a role in the survival of pancreatic islet cells. In addition, chemical modifications that change the collagen charge profile to a net positive charge by esterification have been shown to increase the adhesion and proliferation of various cell types. The purpose of this study was to characterize and compare the effects of native collagen (NC) and esterified collagen (EC) on β cell function and survival. After isolation by the collagenase digestion technique, rat islets were cultured with NC and EC in 2 dimensional (2D) and 3 dimensional (3D) environments for a long-term duration in vitro. The cells were assessed for islet adhesion, morphology, viability, glucose-induced insulin secretion, and mRNA expression of glucose metabolism-related genes, and visualized by scanning electron microscopy (SEM). Islet cells attached tightly in the NC group, but islet cell viability was similar in both the NC and EC groups. Glucose-stimulated insulin secretion was higher in the EC group than in the NC group in both 2D and 3D culture. Furthermore, the mRNA expression levels of glucokinase in the EC group were higher than those in the NC group and were associated with glucose metabolism and insulin secretion. Finally, SEM observation confirmed that islets had more intact component cells on EC sponges than on NC sponges. These results indicate that modification of collagen may offer opportunities to improve function and viability of islet cells. - Highlights: • We changed the collagen charge profile to a net positive charge by esterification. • Islets cultured on esterified collagen improved survival in both 2D and 3D culture. • Islets cultured on esterified collagen enhanced glucose-stimulated insulin release. • High levels of glucokinase mRNA may be associated with increased insulin release.

  6. Collagen esterification enhances the function and survival of pancreatic β cells in 2D and 3D culture systems

    Ko, Jae Hyung; Kim, Yang Hee; Jeong, Seong Hee; Lee, Song; Park, Si-Nae; Shim, In Kyong; Kim, Song Cheol

    2015-01-01

    Collagen, one of the most important components of the extracellular matrix (ECM), may play a role in the survival of pancreatic islet cells. In addition, chemical modifications that change the collagen charge profile to a net positive charge by esterification have been shown to increase the adhesion and proliferation of various cell types. The purpose of this study was to characterize and compare the effects of native collagen (NC) and esterified collagen (EC) on β cell function and survival. After isolation by the collagenase digestion technique, rat islets were cultured with NC and EC in 2 dimensional (2D) and 3 dimensional (3D) environments for a long-term duration in vitro. The cells were assessed for islet adhesion, morphology, viability, glucose-induced insulin secretion, and mRNA expression of glucose metabolism-related genes, and visualized by scanning electron microscopy (SEM). Islet cells attached tightly in the NC group, but islet cell viability was similar in both the NC and EC groups. Glucose-stimulated insulin secretion was higher in the EC group than in the NC group in both 2D and 3D culture. Furthermore, the mRNA expression levels of glucokinase in the EC group were higher than those in the NC group and were associated with glucose metabolism and insulin secretion. Finally, SEM observation confirmed that islets had more intact component cells on EC sponges than on NC sponges. These results indicate that modification of collagen may offer opportunities to improve function and viability of islet cells. - Highlights: • We changed the collagen charge profile to a net positive charge by esterification. • Islets cultured on esterified collagen improved survival in both 2D and 3D culture. • Islets cultured on esterified collagen enhanced glucose-stimulated insulin release. • High levels of glucokinase mRNA may be associated with increased insulin release

  7. Controlling cell-free metabolism through physiochemical perturbations.

    Karim, Ashty S; Heggestad, Jacob T; Crowe, Samantha A; Jewett, Michael C

    2018-01-01

    Building biosynthetic pathways and engineering metabolic reactions in cells can be time-consuming due to complexities in cellular metabolism. These complexities often convolute the combinatorial testing of biosynthetic pathway designs needed to define an optimal biosynthetic system. To simplify the optimization of biosynthetic systems, we recently reported a new cell-free framework for pathway construction and testing. In this framework, multiple crude-cell extracts are selectively enriched with individual pathway enzymes, which are then mixed to construct full biosynthetic pathways on the time scale of a day. This rapid approach to building pathways aids in the study of metabolic pathway performance by providing a unique freedom of design to modify and control biological systems for both fundamental and applied biotechnology. The goal of this work was to demonstrate the ability to probe biosynthetic pathway performance in our cell-free framework by perturbing physiochemical conditions, using n-butanol synthesis as a model. We carried out three unique case studies. First, we demonstrated the power of our cell-free approach to maximize biosynthesis yields by mapping physiochemical landscapes using a robotic liquid-handler. This allowed us to determine that NAD and CoA are the most important factors that govern cell-free n-butanol metabolism. Second, we compared metabolic profile differences between two different approaches for building pathways from enriched lysates, heterologous expression and cell-free protein synthesis. We discover that phosphate from PEP utilization, along with other physiochemical reagents, during cell-free protein synthesis-coupled, crude-lysate metabolic system operation inhibits optimal cell-free n-butanol metabolism. Third, we show that non-phosphorylated secondary energy substrates can be used to fuel cell-free protein synthesis and n-butanol biosynthesis. Taken together, our work highlights the ease of using cell-free systems to explore

  8. Polyamine metabolism in synchronously growing mammalian cells

    Heby, O.; Marton, L.J.; Gray, J.W.; Lindl, P.A.; Wilson, C.B.

    1976-03-02

    The times of synthesis of the polyamines putrescine, spermidine and spermine in relation to the cell cycle have been examined in Chinese hamster ovary (CHO) cells synchronized by selective detachment of mitotic cells. This technique produced cell populations with narrow age distributions. Following plating, the cells grew with high synchrony for more than one cell cycle in monolayer culture. At various times after plating, the distribution of cells among the G1, S and G2M phases of the cell cycle was calculated from DNA histograms obtained by flow microfluorometric analysis. At these same times L-ornithine decarboxylase assays and polyamine determinations showed that the synthesis of the polyamines was initiated in mid-G1 and that the polyamines started to accumulate towards the end of the G1 phase. Maximal rate of synthesis was obtained as the cells started to synthesize DNA and the highest polyamine content was obtained in the beginning of the S phase. Synthesis and accumulation of the polyamines decreased significantly during mid-S but towards the end of the S phase they increased again. The polyamine biosynthetic activity and the concentration of the polyamines reached a second maximum prior to cell division. The role of the polyamines in the traverse of the cell cycle and especially in the initiation or continuation of DNA synthesis is indicated also by the fact that fewer cells were found in the S phase when spermidine and spermine synthesis was inhibited by methylglyoxal-bis(guanylhydrazone).

  9. Role for protein geranylgeranylation in adult T-cell leukemia cell survival

    Nonaka, Mizuho; Uota, Shin; Saitoh, Yasunori; Takahashi, Mayumi; Sugimoto, Haruyo; Amet, Tohti; Arai, Ayako; Miura, Osamu; Yamamoto, Naoki; Yamaoka, Shoji

    2009-01-01

    Adult T-cell leukemia (ATL) is a fatal lymphoproliferative disease that develops in human T-cell leukemia virus type I (HTLV-I)-infected individuals. Despite the accumulating knowledge of the molecular biology of HTLV-I-infected cells, effective therapeutic strategies remain to be established. Recent reports showed that the hydroxyl-3-methylglutaryl (HMG)-CoA reductase inhibitor statins have anti-proliferative and apoptotic effects on certain tumor cells through inhibition of protein prenylation. Here, we report that statins hinder the survival of ATL cells and induce apoptotic cell death. Inhibition of protein geranylgeranylation is responsible for these effects, since simultaneous treatment with isoprenoid precursors, geranylgeranyl pyrophosphate or farnesyl pyrophosphate, but not a cholesterol precursor squalene, restored the viability of ATL cells. Simvastatin inhibited geranylgeranylation of small GTPases Rab5B and Rac1 in ATL cells, and a geranylgeranyl transferase inhibitor GGTI-298 reduced ATL cell viability more efficiently than a farnesyl transferase inhibitor FTI-277. These results not only unveil an important role for protein geranylgeranylation in ATL cell survival, but also implicate therapeutic potentials of statins in the treatment of ATL

  10. Matrix rigidity regulates cancer cell growth by modulating cellular metabolism and protein synthesis.

    Robert W Tilghman

    Full Text Available Tumor cells in vivo encounter diverse types of microenvironments both at the site of the primary tumor and at sites of distant metastases. Understanding how the various mechanical properties of these microenvironments affect the biology of tumor cells during disease progression is critical in identifying molecular targets for cancer therapy.This study uses flexible polyacrylamide gels as substrates for cell growth in conjunction with a novel proteomic approach to identify the properties of rigidity-dependent cancer cell lines that contribute to their differential growth on soft and rigid substrates. Compared to cells growing on more rigid/stiff substrates (>10,000 Pa, cells on soft substrates (150-300 Pa exhibited a longer cell cycle, due predominantly to an extension of the G1 phase of the cell cycle, and were metabolically less active, showing decreased levels of intracellular ATP and a marked reduction in protein synthesis. Using stable isotope labeling of amino acids in culture (SILAC and mass spectrometry, we measured the rates of protein synthesis of over 1200 cellular proteins under growth conditions on soft and rigid/stiff substrates. We identified cellular proteins whose syntheses were either preferentially inhibited or preserved on soft matrices. The former category included proteins that regulate cytoskeletal structures (e.g., tubulins and glycolysis (e.g., phosphofructokinase-1, whereas the latter category included proteins that regulate key metabolic pathways required for survival, e.g., nicotinamide phosphoribosyltransferase, a regulator of the NAD salvage pathway.The cellular properties of rigidity-dependent cancer cells growing on soft matrices are reminiscent of the properties of dormant cancer cells, e.g., slow growth rate and reduced metabolism. We suggest that the use of relatively soft gels as cell culture substrates would allow molecular pathways to be studied under conditions that reflect the different mechanical

  11. Curcumin affects cell survival and cell volume regulation in human renal and intestinal cells

    Kössler, Sonja; Nofziger, Charity; Jakab, Martin; Dossena, Silvia; Paulmichl, Markus

    2012-01-01

    Curcumin (1,7-bis(4-hydroxy-3-methoxyphenyl)-1E,6E-heptadiene-3,5-dione or diferuloyl methane) is a polyphenol derived from the Curcuma longa plant, commonly known as turmeric. This substance has been used extensively in Ayurvedic medicine for centuries for its anti-oxidant, analgesic, anti-inflammatory and antiseptic activity. More recently curcumin has been found to possess anti-cancer properties linked to its pro-apoptotic and anti-proliferative actions. The underlying mechanisms of these diverse effects are complex, not fully elucidated and subject of intense scientific debate. Despite increasing evidence indicating that different cation channels can be a molecular target for curcumin, very little is known about the effect of curcumin on chloride channels. Since, (i) the molecular structure of curcumin indicates that the substance could potentially interact with chloride channels, (ii) chloride channels play a role during the apoptotic process and regulation of the cell volume, and (iii) apoptosis is a well known effect of curcumin, we set out to investigate whether or not curcumin could (i) exert a modulatory effect (direct or indirect) on the swelling activated chloride current IClswell in a human cell system, therefore (ii) affect cell volume regulation and (iii) ultimately modulate cell survival. The IClswell channels, which are essential for regulating the cell volume after swelling, are also known to be activated under isotonic conditions as an early event in the apoptotic process. Here we show that long-term exposure of a human kidney cell line to extracellular 0.1–10 μM curcumin modulates IClswell in a dose-dependent manner (0.1 μM curcumin is ineffective, 0.5–5.0 μM curcumin increase, while 10 μM curcumin decrease the current), and short-term exposure to micromolar concentrations of curcumin does not affect IClswell neither if applied from the extracellular nor from the intracellular side – therefore, a direct effect of curcumin on

  12. Curcumin affects cell survival and cell volume regulation in human renal and intestinal cells

    Kössler, Sonja; Nofziger, Charity; Jakab, Martin; Dossena, Silvia; Paulmichl, Markus

    2012-01-01

    Curcumin (1,7-bis(4-hydroxy-3-methoxyphenyl)-1E,6E-heptadiene-3,5-dione or diferuloyl methane) is a polyphenol derived from the Curcuma longa plant, commonly known as turmeric. This substance has been used extensively in Ayurvedic medicine for centuries for its anti-oxidant, analgesic, anti-inflammatory and antiseptic activity. More recently curcumin has been found to possess anti-cancer properties linked to its pro-apoptotic and anti-proliferative actions. The underlying mechanisms of these diverse effects are complex, not fully elucidated and subject of intense scientific debate. Despite increasing evidence indicating that different cation channels can be a molecular target for curcumin, very little is known about the effect of curcumin on chloride channels. Since, (i) the molecular structure of curcumin indicates that the substance could potentially interact with chloride channels, (ii) chloride channels play a role during the apoptotic process and regulation of the cell volume, and (iii) apoptosis is a well known effect of curcumin, we set out to investigate whether or not curcumin could (i) exert a modulatory effect (direct or indirect) on the swelling activated chloride current ICl swell in a human cell system, therefore (ii) affect cell volume regulation and (iii) ultimately modulate cell survival. The ICl swell channels, which are essential for regulating the cell volume after swelling, are also known to be activated under isotonic conditions as an early event in the apoptotic process. Here we show that long-term exposure of a human kidney cell line to extracellular 0.1–10 μM curcumin modulates ICl swell in a dose-dependent manner (0.1 μM curcumin is ineffective, 0.5–5.0 μM curcumin increase, while 10 μM curcumin decrease the current), and short-term exposure to micromolar concentrations of curcumin does not affect ICl swell neither if applied from the extracellular nor from the intracellular side – therefore, a direct effect of curcumin on ICl

  13. Mechanosensation Dynamically Coordinates Polar Growth and Cell Wall Assembly to Promote Cell Survival.

    Davì, Valeria; Tanimoto, Hirokazu; Ershov, Dmitry; Haupt, Armin; De Belly, Henry; Le Borgne, Rémi; Couturier, Etienne; Boudaoud, Arezki; Minc, Nicolas

    2018-04-23

    How growing cells cope with size expansion while ensuring mechanical integrity is not known. In walled cells, such as those of microbes and plants, growth and viability are both supported by a thin and rigid encasing cell wall (CW). We deciphered the dynamic mechanisms controlling wall surface assembly during cell growth, using a sub-resolution microscopy approach to monitor CW thickness in live rod-shaped fission yeast cells. We found that polar cell growth yielded wall thinning and that thickness negatively influenced growth. Thickness at growing tips exhibited a fluctuating behavior with thickening phases followed by thinning phases, indicative of a delayed feedback promoting thickness homeostasis. This feedback was mediated by mechanosensing through the CW integrity pathway, which probes strain in the wall to adjust synthase localization and activity to surface growth. Mutants defective in thickness homeostasis lysed by rupturing the wall, demonstrating its pivotal role for walled cell survival. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Cell signalling and phospholipid metabolism. Final report

    Boss, W.F.

    1990-12-31

    These studies explored whether phosphoinositide (PI) has a role in plants analogous to its role in animal cells. Although no parallel activity of PI in signal transduction was found in plant cells, activity of inositol phospholipid kinase was found to be modulated by light and by cell wall degrading enzymes. These studies indicate a major role for inositol phospholipids in plant growth and development as membrane effectors but not as a source of second messengers.

  15. Stem cell factor enhances the survival of murine intestinal stem cells after photon irradiation

    Leigh, B.R.; Khan, W.; Hancock, S.L.

    1995-01-01

    Recombinant rat stem cell factor (SCF) has been shown to decrease lethality in mice exposed to total-body irradiation (TBI) in the lower range of lethality through radioprotection of hematopoietic stem cells and acceleration of bone marrow repopulation. This study evaluates the effect of SCF on the survival of the intestinal mucosal stem cell after TBI. This non-hematopoietic cell is clinically relevant. Gastrointestinal toxicity is common during and after abdominal and pelvic radiation therapy and limits the radiation dose in these regions. As observed with bone marrow, the administration of SCF to mice prior to TBI enhanced the survival of mouse duodenal crypt stem cells. The maximum enhancement of survival was seen when 100 μ/kg of SCF was given intraperitoneally 8 h before irradiation. This regimen increased the survival of duodenal crypt stem cells after 12.0 Gy TBI from 22.5 ± 0.7 per duodenal cross section for controls to 30.0 ± 1.7 after treatment with SCF (P=0.03). The TBI dose producing 50% mortality of 6 days (LD 50/6 ) was increased from 14.9 Gy for control mice to 19.0 Gy for mice treated with SCF (dose modification factor = 1.28). These findings demonstrate that SCF (dose modification factor = 1.28). These findings demonstrate that SCF has radioprotective effects on a non-hematopoietic stem cell population and suggest that SCF may be of clinical value in preventing radiation injury to the intestine. 29 refs., 4 figs

  16. Chaski, a novel Drosophila lactate/pyruvate transporter required in glia cells for survival under nutritional stress.

    Delgado, María Graciela; Oliva, Carlos; López, Estefanía; Ibacache, Andrés; Galaz, Alex; Delgado, Ricardo; Barros, L Felipe; Sierralta, Jimena

    2018-01-19

    The intercellular transport of lactate is crucial for the astrocyte-to-neuron lactate shuttle (ANLS), a model of brain energetics according to which neurons are fueled by astrocytic lactate. In this study we show that the Drosophila chaski gene encodes a monocarboxylate transporter protein (MCT/SLC16A) which functions as a lactate/pyruvate transporter, as demonstrated by heterologous expression in mammalian cell culture using a genetically encoded FRET nanosensor. chaski expression is prominent in the Drosophila central nervous system and it is particularly enriched in glia over neurons. chaski mutants exhibit defects in a high energy demanding process such as synaptic transmission, as well as in locomotion and survival under nutritional stress. Remarkably, locomotion and survival under nutritional stress defects are restored by chaski expression in glia cells. Our findings are consistent with a major role for intercellular lactate shuttling in the brain metabolism of Drosophila.

  17. IL22/IL-22R pathway induces cell survival in human glioblastoma cells.

    Hussein Akil

    Full Text Available Interleukin-22 (IL-22 is a member of the IL-10 cytokine family that binds to a heterodimeric receptor consisting of IL-22 receptor 1 (IL-22R1 and IL-10R2. IL-22R expression was initially characterized on epithelial cells, and plays an essential role in a number of inflammatory diseases. Recently, a functional receptor was detected on cancer cells such as hepatocarcinoma and lung carcinoma, but its presence was not reported in glioblastoma (GBM. Two GBM cell lines and 10 primary cell lines established from patients undergoing surgery for malignant GBM were used to investigate the expression of IL-22 and IL-22R by using quantitative RT-PCR, western blotting and confocal microscopy studies. The role of IL-22 in proliferation and survival of GBM cell lines was investigated in vitro by BrdU and ELISA cell death assays. We report herein that the two subunits of the IL-22R complex are expressed on human GBM cells. Their activation, depending on exogenous IL-22, induced antiapoptotic effect and cell proliferation. IL-22 treatment of GBM cells resulted in increased levels of phosphorylated Akt, STAT3 signaling protein and its downstream antiapoptotic protein Bcl-xL and decreased level of phosphorylated ERK1/2. In addition, IL-22R subunits were expressed in all the 10 tested primary cell lines established from GBM tumors. Our results showed that IL-22R is expressed on GBM established and primary cell lines. Depending on STAT3, ERK1/2 and PI3K/Akt pathways, IL-22 induced GBM cell survival. These data are consistent with a potential role of IL-22R in tumorigenesis of GBM. Since endogenous IL-22 was not detected in all studied GBM cells, we hypothesize that IL-22R could be activated by immune microenvironmental IL-22 producing cells.

  18. Metabolism of murine TH 17 cells: Impact on cell fate and function.

    Wang, Ran; Solt, Laura A

    2016-04-01

    An effective adaptive immune response relies on the ability of lymphocytes to rapidly act upon a variety of insults. In T lymphocytes, this response includes cell growth, clonal expansion, differentiation, and cytokine production, all of which place a significant energy burden on the cell. Recent evidence shows that T-cell metabolic reprogramming is an essential component of the adaptive immune response and specific metabolic pathways dictate T-cell fate decisions, including the development of TH 17 versus T regulatory (Treg) cells. TH 17 cells have garnered significant attention due to their roles in the pathology of immune-mediated inflammatory diseases. Attempts to characterize TH 17 cells have demonstrated that they are highly dynamic, adjusting their function to environmental cues, which dictate their metabolic program. In this review, we highlight recent data demonstrating the impact of cellular metabolism on the TH 17/Treg balance and present factors that mediate TH 17-cell metabolism. Some examples of these include the differential impact of the mTOR signaling complexes on T-helper-cell differentiation, hypoxia inducible factor 1 alpha (HIF1α) promotion of glycolysis to favor TH 17-cell development, and ACC1-dependent de novo fatty acid synthesis favoring TH 17-cell development over Treg cells. Finally, we discuss the potential therapeutic options and the implications of modulating TH 17-cell metabolism for the treatment of TH 17-mediated diseases. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Germ Cell Cancer and Multiple Relapses: Toxicity and Survival

    Lauritsen, Jakob; Kier, Maria G.G.; Mortensen, Mette S.

    2015-01-01

    Purpose: A small number of patients with germ cell cancer (GCC) receive more than one line of treatment for disseminated disease. The purpose of this study was to evaluate late toxicity and survival in an unselected cohort of patients who experienced relapse after receiving first-line treatment...... for disseminated disease. Methods: From the Danish Testicular Cancer database, we identified all patients who received more than one line of treatment for disseminated disease. Information about late toxicity and mortality was obtained by means of linkage to national registers. Prognostic factors for relapse......, compared with patients treated with only orchiectomy, had an increased risk for a second cancer (hazard ratio [HR], 3.2; 95% CI, 1.9 to 5.5), major cardiovascular disease (HR, 1.9; 95% CI, 1.0 to 3.3), pulmonary disease (HR, 2.0; 95% CI, 1.0 to 3.8), GI disease (HR, 7.3; 95% CI, 3.6 to 14.8), renal...

  20. Surviving metabolic arrest: photosynthesis during desiccation and rehydration in resurrection plants.

    Challabathula, Dinakar; Puthur, Jos T; Bartels, Dorothea

    2016-02-01

    Photosynthesis is the key process that is affected by dehydration in plants. Desiccation-tolerant resurrection plants can survive conditions of very low relative water content. During desiccation, photosynthesis is not operational, but is recovered within a short period after rehydration. While homoiochlorophyllous resurrection plants retain their photosynthetic apparatus during desiccation, poikilochlorophyllous resurrection species dismantle chloroplasts and degrade chlorophyll but resynthesize them again during rehydration. Dismantling the chloroplasts avoids the photooxidative stress in poikilochlorophyllous resurrection plants, whereas it is minimized in homoiochlorophyllous plants through the synthesis of antioxidant enzymes and protective proteins or metabolites. Although the cellular protection mechanisms in both of these species vary, these mechanisms protect cells from desiccation-induced damage and restore photosynthesis upon rehydration. Several of the proteins synthesized during dehydration are localized in chloroplasts and are believed to play major roles in the protection of photosynthetic structures and in recovery in resurrection species. This review focuses on the strategies of resurrection plants in terms of how they protect their photosynthetic apparatus from oxidative stress during desiccation without membrane damage and with full recovery during rehydration. We review the role of the dehydration-induced protection mechanisms in chloroplasts and how photosynthesis is restored during rehydration. © 2015 New York Academy of Sciences.

  1. Mechanisms of ROS modulated cell survival during carcinogenesis.

    Clerkin, J S; Naughton, R; Quiney, C; Cotter, T G

    2008-07-18

    There is increasing evidence within the literature that the decreased susceptibility of tumour cells to stimuli that induce apoptosis can be linked to their inherently increased redox potential. The review primarily focuses on the PI3-kinase/Akt pathway, and the multiple points along this signalling pathway that may be redox regulated. The PI3-kinase/Akt pathway can influence a cells' sensitivity to death inducing signals, through direct manipulation of apoptosis regulating molecules or by regulating the activity of key transcription factors. Proteins involved in the control of apoptosis that are directly regulated by the PI3-kinase/Akt pathway include caspase-9, Bad and the transcription factor GSK-3beta. Lately, it is becoming increasingly obvious that phosphatases are a major counter balance to the PI3-kinase/Akt pathway. Phosphatases such as PP2A and PP1alpha can dephosphorylate signalling molecules within the PI3-kinase/Akt pathway, blocking their activity. It is the balance between the kinase activity and the phosphatase activity that determines the presence and strength of the PI3-kinase/Akt signal. This is why any protein modifications that hinder dephosphorylation can increase the tumours survival advantage. One such modification is the oxidation of the sulphydryl group in key cysteine residues present within the active site of the phosphatases. This highlights the link between the increased redox stress in tumours with the PI3-kinase/Akt pathway. This review will discuss the various sources of reactive oxygen species within a tumour and the effect of these radicals on the PI3-kinase/Akt pathway.

  2. SYSTEMS BIOLOGY AND METABOLIC ENGINEERING OF ARTHROSPIRA CELL FACTORIES

    Amornpan Klanchui

    2012-10-01

    Full Text Available Arthrospira are attractive candidates to serve as cell factories for production of many valuable compounds useful for food, feed, fuel and pharmaceutical industries. In connection with the development of sustainable bioprocessing, it is a challenge to design and develop efficient Arthrospira cell factories which can certify effective conversion from the raw materials (i.e. CO2 and sun light into desired products. With the current availability of the genome sequences and metabolic models of Arthrospira, the development of Arthrospira factories can now be accelerated by means of systems biology and the metabolic engineering approach. Here, we review recent research involving the use of Arthrospira cell factories for industrial applications, as well as the exploitation of systems biology and the metabolic engineering approach for studying Arthrospira. The current status of genomics and proteomics through the development of the genome-scale metabolic model of Arthrospira, as well as the use of mathematical modeling to simulate the phenotypes resulting from the different metabolic engineering strategies are discussed. At the end, the perspective and future direction on Arthrospira cell factories for industrial biotechnology are presented.

  3. Shigella reroutes host cell central metabolism to obtain high-flux nutrient supply for vigorous intracellular growth.

    Kentner, David; Martano, Giuseppe; Callon, Morgane; Chiquet, Petra; Brodmann, Maj; Burton, Olga; Wahlander, Asa; Nanni, Paolo; Delmotte, Nathanaël; Grossmann, Jonas; Limenitakis, Julien; Schlapbach, Ralph; Kiefer, Patrick; Vorholt, Julia A; Hiller, Sebastian; Bumann, Dirk

    2014-07-08

    Shigella flexneri proliferate in infected human epithelial cells at exceptionally high rates. This vigorous growth has important consequences for rapid progression to life-threatening bloody diarrhea, but the underlying metabolic mechanisms remain poorly understood. Here, we used metabolomics, proteomics, and genetic experiments to determine host and Shigella metabolism during infection in a cell culture model. The data suggest that infected host cells maintain largely normal fluxes through glycolytic pathways, but the entire output of these pathways is captured by Shigella, most likely in the form of pyruvate. This striking strategy provides Shigella with an abundant favorable energy source, while preserving host cell ATP generation, energy charge maintenance, and survival, despite ongoing vigorous exploitation. Shigella uses a simple three-step pathway to metabolize pyruvate at high rates with acetate as an excreted waste product. The crucial role of this pathway for Shigella intracellular growth suggests targets for antimicrobial chemotherapy of this devastating disease.

  4. Extracellular sphingosine-1-phosphate: a novel actor in human glioblastoma stem cell survival.

    Elena Riccitelli

    Full Text Available Glioblastomas are the most frequent and aggressive intracranial neoplasms in humans, and despite advances and the introduction of the alkylating agent temozolomide in therapy have improved patient survival, resistance mechanisms limit benefits. Recent studies support that glioblastoma stem-like cells (GSCs, a cell subpopulation within the tumour, are involved in the aberrant expansion and therapy resistance properties of glioblastomas, through still unclear mechanisms. Emerging evidence suggests that sphingosine-1-phosphate (S1P a potent onco-promoter able to act as extracellular signal, favours malignant and chemoresistance properties in GSCs. Notwithstanding, the origin of S1P in the GSC environment remains unknown. We investigated S1P metabolism, release, and role in cell survival properties of GSCs isolated from either U87-MG cell line or a primary culture of human glioblastoma. We show that both GSC models, grown as neurospheres and expressing GSC markers, are resistant to temozolomide, despite not expressing the DNA repair protein MGMT, a major contributor to temozolomide-resistance. Pulse experiments with labelled sphingosine revealed that both GSC types are able to rapidly phosphorylate the long-chain base, and that the newly produced S1P is efficiently degraded. Of relevance, we found that S1P was present in GSC extracellular medium, its level being significantly higher than in U87-MG cells, and that the extracellular/intracellular ratio of S1P was about ten-fold higher in GSCs. The activity of sphingosine kinases was undetectable in GSC media, suggesting that mechanisms of S1P transport to the extracellular environment are constitutive in GSCs. In addition we found that an inhibitor of S1P biosynthesis made GSCs sensitive to temozolomide (TMZ, and that exogenous S1P reverted this effect, thus involving extracellular S1P as a GSC survival signal in TMZ resistance. Altogether our data implicate for the first time GSCs as a pivotal source

  5. A Consensus Genome-scale Reconstruction of Chinese Hamster Ovary Cell Metabolism

    Hefzi, Hooman; Ang, Kok Siong; Hanscho, Michael

    2016-01-01

    Chinese hamster ovary (CHO) cells dominate biotherapeutic protein production and are widely used in mammalian cell line engineering research. To elucidate metabolic bottlenecks in protein production and to guide cell engineering and bioprocess optimization, we reconstructed the metabolic pathways...

  6. Platelet adhesion and degranulation induce pro-survival and pro-angiogenic signalling in ovarian cancer cells.

    Karl Egan

    Full Text Available Thrombosis is common in ovarian cancer. However, the interaction of platelets with ovarian cancer cells has not been critically examined. To address this, we investigated platelet interactions in a range of ovarian cancer cell lines with different metastatic potentials [HIO-80, 59M, SK-OV-3, A2780, A2780cis]. Platelets adhered to ovarian cancer cells with the most significant adhesion to the 59M cell line. Ovarian cancer cells induced platelet activation [P-selectin expression] in a dose dependent manner, with the most significant activation seen in response to the 59M cell line. The platelet antagonists [cangrelor, MRS2179, and apyrase] inhibited 59M cell induced activation suggesting a P2Y12 and P2Y1 receptor mediated mechanism of platelet activation dependent on the release of ADP by 59M cells. A2780 and 59M cells potentiated PAR-1, PAR-4, and TxA2 receptor mediated platelet activation, but had no effect on ADP, epinephrine, or collagen induced activation. Analysis of gene expression changes in ovarian cancer cells following treatment with washed platelets or platelet releasate showed a subtle but valid upregulation of anti-apoptotic, anti-autophagy pro-angiogenic, pro-cell cycle and metabolic genes. Thus, ovarian cancer cells with different metastatic potential adhere and activate platelets differentially while both platelets and platelet releasate mediate pro-survival and pro-angiogenic signals in ovarian cancer cells.

  7. Induced pluripotent stem cell-derived neural cells survive and mature in the nonhuman primate brain.

    Emborg, Marina E; Liu, Yan; Xi, Jiajie; Zhang, Xiaoqing; Yin, Yingnan; Lu, Jianfeng; Joers, Valerie; Swanson, Christine; Holden, James E; Zhang, Su-Chun

    2013-03-28

    The generation of induced pluripotent stem cells (iPSCs) opens up the possibility for personalized cell therapy. Here, we show that transplanted autologous rhesus monkey iPSC-derived neural progenitors survive for up to 6 months and differentiate into neurons, astrocytes, and myelinating oligodendrocytes in the brains of MPTP-induced hemiparkinsonian rhesus monkeys with a minimal presence of inflammatory cells and reactive glia. This finding represents a significant step toward personalized regenerative therapies. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Association of ultraviolet-induced retrovirus expression with anchorage-independent survival in rat embryo cells

    Suk, W.A.

    1985-01-01

    The authors have shown in the AI assay that the nontransforming retrovirus increases the differential in enhanced survival response in infected cultures. To more fully understand this aspect of the system, they examined the effect of UV irradiation on infected and uninfected FRE cells. In this communication the authors report that UV irradiation induces AI survival in infected and uninfected cells;in uninfected cells there is a concomitant induction of endogenous retrovirus expression. The AI survival of both cell lines was determined using a previously described procedure. Anchorage-dependent media control and solvent control cells, when suspended in medium above an agar base layer, showed a rapid decline in cell survival;however, cells that had been treated with carcinogen did not undergo the destructive process that took place in control cells, indicating specificity

  9. Altering Cell Survival by Modulating Levels of Mitochondrial DNA Repair Enzymes

    Shokolenko, Inna

    2002-01-01

    .... Our previous results demonstrated that stable expression of E.coli Exonuclease III in mitochondria of breast cancer cells diminishes mtDNA repair capacity following oxidative stress, which leads to a decrease in long-term cell survival...

  10. Differential Reliance on Lipid Metabolism as a Salvage Pathway Underlies Functional Differences of T Cell Subsets in Poor Nutrient Environments

    Christopher Ecker

    2018-04-01

    Full Text Available Summary: T cells compete with malignant cells for limited nutrients within the solid tumor microenvironment. We found that effector memory CD4 T cells respond distinctly from other T cell subsets to limiting glucose and can maintain high levels of interferon-γ (IFN-γ production in a nutrient-poor environment. Unlike naive (TN or central memory T (TCM cells, effector memory T (TEM cells fail to upregulate fatty acid synthesis, oxidative phosphorylation, and reductive glutaminolysis in limiting glucose. Interference of fatty acid synthesis in naive T cells dramatically upregulates IFN-γ, while increasing exogenous lipids in media inhibits production of IFN-γ by all subsets, suggesting that relative ratio of fatty acid metabolism to glycolysis is a direct predictor of T cell effector activity. Together, these data suggest that effector memory T cells are programmed to have limited ability to synthesize and metabolize fatty acids, which allows them to maintain T cell function in nutrient-depleted microenvironments. : Ecker et al. distinguish unique metabolic and functional properties of naive and memory T cell subsets during glucose limitation. During glucose starvation, T cells begin to differentially rely on fatty acid synthesis and glutamine utilization to survive. Unexpectedly, reliance on fatty acid synthesis alters the ability to produce IFN-γ. Keywords: lipid droplets, IFN-γ, oxidative phosphorylation, reductive glutaminolysis, serum-free media, naive T cell, glycolysis, effector memory T cell, fatty acid synthesis

  11. Cell cycle arrest and cell survival induce reverse trends of cardiolipin remodeling.

    Yu-Jen Chao

    Full Text Available Cell survival from the arrested state can be a cause of the cancer recurrence. Transition from the arrest state to the growth state is highly regulated by mitochondrial activity, which is related to the lipid compositions of the mitochondrial membrane. Cardiolipin is a critical phospholipid for the mitochondrial integrity and functions. We examined the changes of cardiolipin species by LC-MS in the transition between cell cycle arrest and cell reviving in HT1080 fibrosarcoma cells. We have identified 41 cardiolipin species by MS/MS and semi-quantitated them to analyze the detailed changes of cardiolipin species. The mass spectra of cardiolipin with the same carbon number form an envelope, and the C64, C66, C68, C70 C72 and C74 envelopes in HT1080 cells show a normal distribution in the full scan mass spectrum. The cardiolipin quantity in a cell decreases while entering the cell cycle arrest, but maintains at a similar level through cell survival. While cells awakening from the arrested state and preparing itself for replication, the groups with short acyl chains, such as C64, C66 and C68 show a decrease of cardiolipin percentage, but the groups with long acyl chains, such as C70 and C72 display an increase of cardiolipin percentage. Interestingly, the trends of the cardiolipin species changes during the arresting state are completely opposite to cell growing state. Our results indicate that the cardiolipin species shift from the short chain to long chain cardiolipin during the transition from cell cycle arrest to cell progression.

  12. Survival of egg-laying controlling neuroendocrine cells during reproductive senescence of a mollusc

    Janse, C.

    2004-01-01

    During brain aging neuronal degradation occurs. In some neurons this may result in degeneration and cell death, still other neurons may survive and maintain their basic properties. The present study deals with survival of the egg-laying controlling neuroendocrine caudodorsal cells (CDCs) during

  13. Intercellular contact: its influence on the Dsub(q) of mammalian cell survival curves

    Durand, R.E.; Sutherland, R.M.

    1975-01-01

    Cell survival in tissues exposed to a given dose of ionizing radiation is usually greater than that of similar cells grown individually in vitro, despite the fact that the radiosensitivities (D 0 ) are virtually identical under the two conditions. An analogous increase in cell survival is observed when Chinese hamster V79-171 cells are grown in suspension culture and irradiated as multicell spheroids. Unfortunately, the information gained from the survival curves so obtained is limited by the inhomogeneity of the cell population with respect to both degree of contact and cell cycle position. The latter can be studied using synchronized small spheroids. The ratio of Dsub(q) of spheroid cells to Dsub(q) of single cells increased as the cells progressed through the cell cycle, from a minimum of 1.3 for G 1 phase cells to a maximum of 2.2 for late S-phase cells. The enhanced survival, or 'contact effect', developed slowly as the spheroids grew, after an initial latent period of about one generation cycle of the cells. A second effect of intercellular contact on mammalian cell survival has also been observed. When cells are assayed under conditions in which intercellular contact is maintained, the net cellular survival is increased further. This effect is different from the usual repair of potentially lethal damage, in that it occurs much more slowly and results in modification of the survival-curve shoulder. Not all cell types tested have shown enhanced survival when grown as spheroids. Several MNNG-induced mutants of the Chinese hamster V79-171 line have been isolated and sublines which do and do not show the contact effect are now available. These may permit study of the mechanism(s) of contact effects. (author)

  14. Low concentrations of Rhodamine-6G selectively destroy tumor cells and improve survival of melanoma transplanted mice.

    Kutushov, M; Gorelik, O

    2013-01-01

    Rhodamine-6G is a fluorescent dye binding to mitochondria, thus reducing the intact mitochondria number and inhibiting mitochondrial metabolic activity. Resultantly, the respiratory chain functioning becomes blocked, the cell "suffocated" and eventually destroyed. Unlike normal cells, malignant cells demonstrate a priori reduced mitochondrial numbers and aberrant metabolism. Therefore, a turning point might exist, when Rhodamine-induced loss of active mitochondria would selectively destroy malignant, but spare normal cells. Various malignant vs. non-malignant cell lines were cultured with Rhodamine-6G at different concentrations. In addition, C57Bl mice were implanted with B16-F10 melanoma and treated with Rhodamine-6G at different dosage/time regimens. Viability and proliferation of cultured tumor cells were time and dose-dependently inhibited, up to 90%, by Rhodamine-6G, with profound histological signs of cell death. By contrast, inhibition of normal control cell proliferation hardly exceeded 15-17%. Melanoma-transplanted mice receiving Rhodamine-6G demonstrated prolonged survival, improved clinical parameters, inhibited tumor growth and metastases count, compared to their untreated counterparts. Twice-a-week 10-6M Rhodamine-6G regimen yielded the most prominent results. We conclude that malignant, but not normal, cells are selectively destroyed by low doses of Rhodamine-6G. In vivo, such treatment selectively suppresses tumor progression and dissemination, thus improving prognosis. We suggest that selective anti-tumor properties of Rhodamine-6G are based on unique physiologic differences in energy metabolism between malignant and normal cells. If found clinically relevant, low concentrations of Rhodamine-6G might be useful for replacing, or backing up, more aggressive nonselective chemotherapeutic compounds.

  15. Effect of visible light on progressive dormancy of Escherichia coli cells during the survival process in natural fresh water

    Barcina, I.; Gonzalez, J.M.; Iriberri, J.; Egea, L.

    1989-01-01

    Some effects of visible light on the survival of Escherichia coli in waters of the Butron river were studied by comparing illuminated and nonilluminated systems. The following count methods were used: CFU on a selective medium (eosin-methylene blue agar), CFU on a medium of recuperation (Trypticase soy agar with yeast extract and glucose), number of metabolically active cells by reduction of 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride (INT) to INT-formazan, and total number of E. coli cells as determined by the acridine orange direct-count method. In the illuminated systems, decreases in CFU of E. coli and in the number of metabolically active cells were observed. However, no decline of the total number of E. coli cells was observed. By count methods, different stages of progressive dormancy of E. coli cells were determined to exist in illuminated systems. Culturable and recoverable cells were defined as viable cells, and metabolically active cells and morphologically intact cells were defined as somnicells. Indirect activity measurements were also done by using [14C]glucose. In illuminated systems, a decrease of glucose uptake by E. coli cells was observed throughout the experiments. The assimilated fraction of [14C]glucose decreased faster than the respired fraction in illuminated systems. The percentage of respired [14C]glucose (14CO2 production) with respect to the total glucose uptake increased throughout the experiments, and the percentage of assimilated glucose decreased. Therefore, the visible light was also responsible for an additional inhibition of biosynthetic processes

  16. Free fatty acids and their metabolism affect function and survival of podocytes

    Jonas eSieber

    2014-10-01

    Full Text Available Podocyte injury and loss critically contribute to the pathogenesis of proteinuric kidney diseases including diabetic nephropathy. Deregulated lipid metabolism with disturbed free fatty acid (FFA metabolism is a characteristic of metabolically unhealthy obesity and type 2 diabetes and likely contributes to end-stage kidney disease irrespective of the underlying kidney disease. In the current review we summarize recent findings related to FFAs and altered renal FFA metabolism with a special focus on podocytes. We will outline the opposing effects of saturated and monounsaturated FFAs and a particular emphasis will be given to the underlying molecular mechanisms involving insulin resistance and endoplasmic reticulum homeostasis. Finally, recent data suggesting a critical role of renal FFA metabolism to adapt to an altered lipid environment will be discussed.

  17. Impact of different temperatures on survival and energy metabolism in the Asian citrus psyllid, Diaphorina citri Kuwayama.

    El-Shesheny, Ibrahim; Hijaz, Faraj; El-Hawary, Ibrahim; Mesbah, Ibrahim; Killiny, Nabil

    2016-02-01

    Temperature influences the life history and metabolic parameters of insects. Asian citrus psyllid (ACP), Diaphorina citri is a tropical and subtropical pest. ACP invaded new regions around the world and threatened the citrus industry as a vector for Huanglongbing (HLB) disease. ACP is widely distributed and can survive high (up to 45 °C) and low temperatures (as low as -6 °C). The precise mechanism of temperature tolerance in ACP is poorly understood. We investigated adult survival, cellular energy balance, gene expression, and nucleotide and sugar-nucleotide changes under the effect of different temperature regimes (0 °C to 45 °C with 5 °C intervals). The optimum temperatures for survival were 20 and 25 °C. Low temperatures of 0 °C and 5 °C caused 50% mortality after 2 and 4 days respectively, while one day at high temperature (40 °C and 45 °C) caused more than 95% mortality. The lowest quantity of ATP (3.69 ± 1.6 ng/insect) and the maximum ATPase enzyme activities (57.43 ± 7.6 μU/insect) were observed at 25 °C. Correlation between ATP quantities and ATPase activity was negative. Gene expression of hsp 70, V-type proton ATPase catalytic subunit A and ATP synthase α subunit matched these results. Twenty-four nucleotides and sugar-nucleotides were quantified using HPLC in ACP adults maintained at low, high, and optimum temperatures. The nucleotide profiles were different among treatments. The ratios between AMP:ATP and ADP:ATP were significantly decreased and positively correlated to adults survival, whereas the adenylate energy charge was increased in response to low and high temperatures. Exploring energy metabolic regulation in relation with adult survival might help in understanding the physiological basis of how ACP tolerates newly invaded regions. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Pancreatic stellate cells support tumour metabolism through autophagic alanine secretion.

    Sousa, Cristovão M; Biancur, Douglas E; Wang, Xiaoxu; Halbrook, Christopher J; Sherman, Mara H; Zhang, Li; Kremer, Daniel; Hwang, Rosa F; Witkiewicz, Agnes K; Ying, Haoqiang; Asara, John M; Evans, Ronald M; Cantley, Lewis C; Lyssiotis, Costas A; Kimmelman, Alec C

    2016-08-25

    Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease characterized by an intense fibrotic stromal response and deregulated metabolism. The role of the stroma in PDAC biology is complex and it has been shown to play critical roles that differ depending on the biological context. The stromal reaction also impairs the vasculature, leading to a highly hypoxic, nutrient-poor environment. As such, these tumours must alter how they capture and use nutrients to support their metabolic needs. Here we show that stroma-associated pancreatic stellate cells (PSCs) are critical for PDAC metabolism through the secretion of non-essential amino acids (NEAA). Specifically, we uncover a previously undescribed role for alanine, which outcompetes glucose and glutamine-derived carbon in PDAC to fuel the tricarboxylic acid (TCA) cycle, and thus NEAA and lipid biosynthesis. This shift in fuel source decreases the tumour’s dependence on glucose and serum-derived nutrients, which are limited in the pancreatic tumour microenvironment. Moreover, we demonstrate that alanine secretion by PSCs is dependent on PSC autophagy, a process that is stimulated by cancer cells. Thus, our results demonstrate a novel metabolic interaction between PSCs and cancer cells, in which PSC-derived alanine acts as an alternative carbon source. This finding highlights a previously unappreciated metabolic network within pancreatic tumours in which diverse fuel sources are used to promote growth in an austere tumour microenvironment.

  19. Metabolic therapy with Deanna Protocol supplementation delays disease progression and extends survival in amyotrophic lateral sclerosis (ALS mouse model.

    Csilla Ari

    Full Text Available Amyotrophic Lateral Sclerosis (ALS, also known as Lou Gehrig's disease, is a neurodegenerative disorder of motor neurons causing progressive muscle weakness, paralysis, and eventual death from respiratory failure. There is currently no cure or effective treatment for ALS. Besides motor neuron degeneration, ALS is associated with impaired energy metabolism, which is pathophysiologically linked to mitochondrial dysfunction and glutamate excitotoxicity. The Deanna Protocol (DP is a metabolic therapy that has been reported to alleviate symptoms in patients with ALS. In this study we hypothesized that alternative fuels in the form of TCA cycle intermediates, specifically arginine-alpha-ketoglutarate (AAKG, the main ingredient of the DP, and the ketogenic diet (KD, would increase motor function and survival in a mouse model of ALS (SOD1-G93A. ALS mice were fed standard rodent diet (SD, KD, or either diets containing a metabolic therapy of the primary ingredients of the DP consisting of AAKG, gamma-aminobutyric acid, Coenzyme Q10, and medium chain triglyceride high in caprylic triglyceride. Assessment of ALS-like pathology was performed using a pre-defined criteria for neurological score, accelerated rotarod test, paw grip endurance test, and grip strength test. Blood glucose, blood beta-hydroxybutyrate, and body weight were also monitored. SD+DP-fed mice exhibited improved neurological score from age 116 to 136 days compared to control mice. KD-fed mice exhibited better motor performance on all motor function tests at 15 and 16 weeks of age compared to controls. SD+DP and KD+DP therapies significantly extended survival time of SOD1-G93A mice by 7.5% (p = 0.001 and 4.2% (p = 0.006, respectively. Sixty-three percent of mice in the KD+DP and 72.7% of the SD+DP group lived past 125 days, while only 9% of the control animals survived past that point. Targeting energy metabolism with metabolic therapy produces a therapeutic effect in ALS mice which

  20. Metabolic therapy with Deanna Protocol supplementation delays disease progression and extends survival in amyotrophic lateral sclerosis (ALS) mouse model.

    Ari, Csilla; Poff, Angela M; Held, Heather E; Landon, Carol S; Goldhagen, Craig R; Mavromates, Nicholas; D'Agostino, Dominic P

    2014-01-01

    Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig's disease, is a neurodegenerative disorder of motor neurons causing progressive muscle weakness, paralysis, and eventual death from respiratory failure. There is currently no cure or effective treatment for ALS. Besides motor neuron degeneration, ALS is associated with impaired energy metabolism, which is pathophysiologically linked to mitochondrial dysfunction and glutamate excitotoxicity. The Deanna Protocol (DP) is a metabolic therapy that has been reported to alleviate symptoms in patients with ALS. In this study we hypothesized that alternative fuels in the form of TCA cycle intermediates, specifically arginine-alpha-ketoglutarate (AAKG), the main ingredient of the DP, and the ketogenic diet (KD), would increase motor function and survival in a mouse model of ALS (SOD1-G93A). ALS mice were fed standard rodent diet (SD), KD, or either diets containing a metabolic therapy of the primary ingredients of the DP consisting of AAKG, gamma-aminobutyric acid, Coenzyme Q10, and medium chain triglyceride high in caprylic triglyceride. Assessment of ALS-like pathology was performed using a pre-defined criteria for neurological score, accelerated rotarod test, paw grip endurance test, and grip strength test. Blood glucose, blood beta-hydroxybutyrate, and body weight were also monitored. SD+DP-fed mice exhibited improved neurological score from age 116 to 136 days compared to control mice. KD-fed mice exhibited better motor performance on all motor function tests at 15 and 16 weeks of age compared to controls. SD+DP and KD+DP therapies significantly extended survival time of SOD1-G93A mice by 7.5% (p = 0.001) and 4.2% (p = 0.006), respectively. Sixty-three percent of mice in the KD+DP and 72.7% of the SD+DP group lived past 125 days, while only 9% of the control animals survived past that point. Targeting energy metabolism with metabolic therapy produces a therapeutic effect in ALS mice which may prolong

  1. Impact of the basal metabolic ratio in predicting early deaths after allogeneic stem cell transplantation.

    Nishiwaki, Satoshi; Miyamura, Koichi; Seto, Aika; Watanabe, Keisuke; Yanagisawa, Mayumi; Imahashi, Nobuhiko; Shimba, Makoto; Yasuda, Takahiko; Kuwatsuka, Yachiyo; Oba, Taku; Terakura, Seitaro; Kodera, Yoshihisa

    2009-09-01

    Early deaths after allogeneic stem cell transplantation (allo-SCT) are of major concern. On the assumption that both decreased and increased basal metabolism might relate to early deaths, we analyzed the risk factors for overall survival to days 30 (OS30) and 60 (OS60). The Harris-Benedict equation was used to calculate basal metabolism. Comparing a patient's basal metabolism (PBM) calculated from pretransplant body weight with the standard basal metabolism (SBM) calculated from standard body weight (body mass index (BMI) = 22), we defined the basal metabolic ratio (BMR) as a parameter (BMR = PBM/SBM). We retrospectively analyzed 360 adult patients transplanted between 1997 and 2006 at a single center in Japan. A multivariate analysis of OS30 showed risk factors to be: BMR BMR; LBR) (P = 0.01), BMR > 1.05 (high BMR; HBR) (P = 0.005) and non-complete remission (non-CR) (P 5 0.001), whereas a multivariate analysis of OS60 showed those risk factors to be: LBR (P = 0.02), HBR (P = 0.04), non-CR (P = 0.002), and performance status BMR BMR; ABR) (96.8 and 90.3% for ABR, 87.1 and 76.2% for LBR, and 87.8 and 81.1% for HBR). In conclusion, BMR could prove to be a predictor of early death after allo-SCT.

  2. Natural Killer Cell Activity and Interleukin-12 in Metabolically Healthy versus Metabolically Unhealthy Overweight Individuals

    Kim, Minjoo; Kim, Minkyung; Yoo, Hye Jin; Lee, Jong Ho

    2017-01-01

    The purpose of this study was to determine whether the immune system is involved in the different metabolic circumstances in healthy and unhealthy overweight individuals. We examined the metabolic and immune characteristics of 117 overweight individuals. Subjects were classified as metabolically healthy overweight (MHO, n = 72) or metabolically unhealthy overweight (MUO, n = 45). The immune response was measured by circulating levels of natural killer (NK) cell activity and cytokines. Both groups were comparable with regards to age, sex distribution, smoking and drinking status, and body mass index. When compared to the MHO group, the MUO group showed higher systolic and diastolic blood pressure, serum levels of triglyceride, glucose, glucose-related markers, and lower levels of HDL cholesterol. Compared to the MHO group, the MUO group showed 39% lower interferon-γ levels (not significant) and 41% lower interleukin (IL)-12 levels (significant). The MUO group also showed lower NK cell activity at E:T ratios of 10:1, 5:1, 2.5:1, and 1.25:1 (all Ps < 0.05) than the MHO group. This study indicates that individuals displaying the MUO phenotype present an unfavorable immune system with lower NK cell activities under all assay conditions and lower serum levels of IL-12 than the activities and levels in similarly overweight MHO individuals. This result suggests that the immune system may be altered in overweight individuals who are at risk for overweight/obesity-related comorbidities. PMID:29238351

  3. Natural Killer Cell Activity and Interleukin-12 in Metabolically Healthy versus Metabolically Unhealthy Overweight Individuals

    Minjoo Kim

    2017-11-01

    Full Text Available The purpose of this study was to determine whether the immune system is involved in the different metabolic circumstances in healthy and unhealthy overweight individuals. We examined the metabolic and immune characteristics of 117 overweight individuals. Subjects were classified as metabolically healthy overweight (MHO, n = 72 or metabolically unhealthy overweight (MUO, n = 45. The immune response was measured by circulating levels of natural killer (NK cell activity and cytokines. Both groups were comparable with regards to age, sex distribution, smoking and drinking status, and body mass index. When compared to the MHO group, the MUO group showed higher systolic and diastolic blood pressure, serum levels of triglyceride, glucose, glucose-related markers, and lower levels of HDL cholesterol. Compared to the MHO group, the MUO group showed 39% lower interferon-γ levels (not significant and 41% lower interleukin (IL-12 levels (significant. The MUO group also showed lower NK cell activity at E:T ratios of 10:1, 5:1, 2.5:1, and 1.25:1 (all Ps < 0.05 than the MHO group. This study indicates that individuals displaying the MUO phenotype present an unfavorable immune system with lower NK cell activities under all assay conditions and lower serum levels of IL-12 than the activities and levels in similarly overweight MHO individuals. This result suggests that the immune system may be altered in overweight individuals who are at risk for overweight/obesity-related comorbidities.

  4. Conditional survival of patients with diffuse large B-cell lymphoma

    Møller, Michael Boe; Pedersen, Niels Tinggaard; Christensen, Bjarne E

    2006-01-01

    BACKGROUND: Prognosis of lymphoma patients is usually estimated at the time of diagnosis and the estimates are guided by the International Prognostic Index (IPI). However, conditional survival estimates are more informative clinically, as they consider those patients only who have already survive...... survival probability provides more accurate prognostic information than the conventional survival rate estimated from the time of diagnosis.......BACKGROUND: Prognosis of lymphoma patients is usually estimated at the time of diagnosis and the estimates are guided by the International Prognostic Index (IPI). However, conditional survival estimates are more informative clinically, as they consider those patients only who have already survived...... a period of time after treatment. Conditional survival data have not been reported for lymphoma patients. METHODS: Conditional survival was estimated for 1209 patients with diffuse large B-cell lymphoma (DLBCL) from the population-based LYFO registry of the Danish Lymphoma Group. The Kaplan-Meier method...

  5. Metabolic behavior of cell surface biotinylated proteins

    Hare, J.F.; Lee, E.

    1989-01-01

    The turnover of proteins on the surface of cultured mammalian cells was measured by a new approach. Reactive free amino or sulfhydryl groups on surface-accessible proteins were derivatized with biotinyl reagents and the proteins solubilized from culture dishes with detergent. Solubilized, biotinylated proteins were then adsorbed onto streptavidin-agarose, released with sodium dodecyl sulfate and mercaptoethanol, and separated on polyacrylamide gels. Biotin-epsilon-aminocaproic acid N-hydroxysuccinimide ester (BNHS) or N-biotinoyl-N'-(maleimidohexanoyl)hydrazine (BM) were the derivatizing agents. Only 10-12 bands were adsorbed onto streptavidin-agarose from undervatized cells or from derivatized cells treated with free avidin at 4 degrees C. Two-dimensional isoelectric focusing-sodium dodecyl sulfate gel electrophoresis resolved greater than 100 BNHS-derivatized proteins and greater than 40 BM-derivatized proteins. There appeared to be little overlap between the two groups of derivatized proteins. Short-term pulse-chase studies showed an accumulation of label into both groups of biotinylated proteins up until 1-2 h of chase and a rapid decrease over the next 1-5 h. Delayed appearance of labeled protein at the cell surface was attributed to transit time from site of synthesis. The unexpected and unexplained rapid disappearance of pulse-labeled proteins from the cell surface was invariant for all two-dimensionally resolved proteins and was sensitive to temperature reduction to 18 degrees C. Long-term pulse-chase experiments beginning 4-8 h after the initiation of chase showed the disappearance of derivatized proteins to be a simple first-order process having a half-life of 115 h in the case of BNHS-derivatized proteins and 30 h in the case of BM-derivatized proteins

  6. Targeting Lipid Metabolic Reprogramming as Anticancer Therapeutics

    Cha, Ji-Young; Lee, Ho-Jae

    2016-01-01

    Cancer cells rewire their metabolism to satisfy the demands of growth and survival, and this metabolic reprogramming has been recognized as an emerging hallmark of cancer. Lipid metabolism is pivotal in cellular process that converts nutrients into energy, building blocks for membrane biogenesis and the generation of signaling molecules. Accumulating evidence suggests that cancer cells show alterations in different aspects of lipid metabolism. The changes in lipid metabolism of cancer cells c...

  7. Radiobiological effects of tritiated water short-term exposure on V79 clonogenic cell survival

    Siragusa, Mattia; Fredericia, Nina Pil Møntegaard; Jensen, Mikael

    2018-01-01

    We set out to improve the accuracy of absorbed dose calculations for in-vitro measurements of the Relative Biological Effectiveness (RBE) of tritiated water (HTO) for the clonogenic cell survival assay, also considering the influence of the end-of-track Linear Energy Transfer (LET) of low-energy...... in suspension are usually comparable to those for adherent cells. RBEs calculated at the 10% survival fraction through the use of the average energy are almost similar to those obtained with the beta-spectrum. For adherent cells, an RBE of 1.6 was found when HTO cell survival curves were compared to acute γ...

  8. Melatonin redirects carbohydrates metabolism during sugar starvation in plant cells.

    Kobylińska, Agnieszka; Borek, Sławomir; Posmyk, Małgorzata M

    2018-05-01

    Recent studies have shown that melatonin is an important molecule in plant physiology. It seems that the most important is that melatonin efficacy eliminates oxidative stress (direct and indirect antioxidant) and moreover induce plant stress reaction and switch on different defence strategies (preventively and interventively actions). In this report, the impact of exogenous melatonin on carbohydrate metabolism in Nicotiana tabacum L. line Bright Yellow 2 (BY-2) suspension cells during sugar starvation was examined. We analysed starch concentration, α-amylase and PEPCK activity as well as proteolytic activity in culture media. It has been shown that BY-2 cell treatment with 200 nM of melatonin improved viability of sugar-starved cells. It was correlated with higher starch content and phosphoenolpyruvate carboxykinase (PEPCK) activity. The obtained results revealed that exogenous melatonin under specific conditions (stress) can play regulatory role in sugar metabolism, and it may modulate carbohydrate concentration in etiolated BY-2 cells. Moreover, our results confirmed the hypothesis that if the starch is synthesised even in sugar-starved cells, it is highly probable that melatonin shifts the BY-2 cell metabolism on gluconeogenesis pathway and allows for synthesis of carbohydrates from nonsugar precursors, that is amino acids. These points to another defence strategy that was induced by exogenous melatonin applied in plants to overcome adverse environmental conditions. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Dendrogenin A arises from cholesterol and histamine metabolism and shows cell differentiation and anti-tumour properties.

    de Medina, Philippe; Paillasse, Michael R; Segala, Gregory; Voisin, Maud; Mhamdi, Loubna; Dalenc, Florence; Lacroix-Triki, Magali; Filleron, Thomas; Pont, Frederic; Saati, Talal Al; Morisseau, Christophe; Hammock, Bruce D; Silvente-Poirot, Sandrine; Poirot, Marc

    2013-01-01

    We previously synthesized dendrogenin A and hypothesized that it could be a natural metabolite occurring in mammals. Here we explore this hypothesis and report the discovery of dendrogenin A in mammalian tissues and normal cells as an enzymatic product of the conjugation of 5,6α-epoxy-cholesterol and histamine. Dendrogenin A was not detected in cancer cell lines and was fivefold lower in human breast tumours compared with normal tissues, suggesting a deregulation of dendrogenin A metabolism during carcinogenesis. We established that dendrogenin A is a selective inhibitor of cholesterol epoxide hydrolase and it triggered tumour re-differentiation and growth control in mice and improved animal survival. The properties of dendrogenin A and its decreased level in tumours suggest a physiological function in maintaining cell integrity and differentiation. The discovery of dendrogenin A reveals a new metabolic pathway at the crossroads of cholesterol and histamine metabolism and the existence of steroidal alkaloids in mammals.

  10. Remembrance of Dead Cells Past: Discovering That the Extracellular Matrix Is a Cell Survival Factor

    Schwartz, Martin A.

    2010-01-01

    In 1992, Jere Meredith and I followed up on a serendipitous observation and showed that matrix deprivation can lead to apoptosis. Our article in Molecular Biology of the Cell, together with work form Steve Frisch's lab, helped establish the paradigm that integrin signals control cell survival in a variety of systems. It has been a pleasure to watch that work take on a life of its own as other investigators have explored its role in processes such as cavitation, regression of the mammary gland...

  11. Molecular Imaging Of Metabolic Reprogramming In Mutant IDH Cells

    Pavithra eViswanath

    2016-03-01

    Full Text Available Mutations in the metabolic enzyme isocitrate dehydrogenase (IDH have recently been identified as drivers in the development of several tumor types. Most notably, cytosolic IDH1 is mutated in 70-90% of low-grade gliomas and upgraded glioblastomas, and mitochondrial IDH2 is mutated in ~20% of acute myeloid leukemia cases. Wild-type IDH catalyzes the interconversion of isocitrate to α-ketoglutarate (α-KG. Mutations in the enzyme lead to loss of wild-type enzymatic activity and a neomorphic activity that converts α-KG to 2-hydroxyglutarate (2-HG. In turn, 2-HG, which has been termed an oncometabolite, inhibits key α-KG- dependent enzymes, resulting in alterations of the cellular epigenetic profile and, subsequently, inhibition of differentiation and initiation of tumorigenesis. In addition, it is now clear that the IDH mutation also induces a broad metabolic reprogramming that extends beyond 2-HG production, and this reprogramming often differs from what has been previously reported in other cancer types. In this review we will discuss in detail what is known to date about the metabolic reprogramming of mutant IDH cells and how this reprogramming has been investigated using molecular metabolic imaging. We will describe how metabolic imaging has helped shed light on the basic biology of mutant IDH cells and how this information can be leveraged to identify new therapeutic targets and to develop new clinically translatable imaging methods to detect and monitor mutant IDH tumors in vivo.

  12. Enhanced endogenous type I interferon cell-driven survival and inhibition of spontaneous apoptosis by Riluzole

    Achour, Ammar; M'Bika, Jean-Pierre; Biquard, Jean-Michel

    2009-01-01

    Highly active antiretroviral therapy (HAART), although effective in improving the survival of HIV-1-infected individuals, has not been able to reconstitute the adaptive immune response. We have described the use of novel chemical agents to restore T-cell survival/proliferation by inducing cytokine production. Due to its cationic amphiphilic structure, these molecules appear to enhance immune restoration. In this study, we investigated the action of Riluzole (2-amino-6-trifuromethoxybenzothiazole) in HIV-1 infection. Riluzole is able to increase (effective dose from 1 to 1000 nM) the cell-survival of T cells from HIV-1-infected patients and inhibit spontaneous apoptosis. The immunomodulatory effect of riluzole-sensitized cells was ascribed to endogenous type I interferon (IFN) derived from monocytes. Riluzole might be used for restoring the cell survival of immunocompromised patients and eliminating latent infected cells upon HIV-1 reactivation

  13. Plasma Rich in Growth Factors Induces Cell Proliferation, Migration, Differentiation, and Cell Survival of Adipose-Derived Stem Cells.

    Mellado-López, Maravillas; Griffeth, Richard J; Meseguer-Ripolles, Jose; Cugat, Ramón; García, Montserrat; Moreno-Manzano, Victoria

    2017-01-01

    Adipose-derived stem cells (ASCs) are a promising therapeutic alternative for tissue repair in various clinical applications. However, restrictive cell survival, differential tissue integration, and undirected cell differentiation after transplantation in a hostile microenvironment are complications that require refinement. Plasma rich in growth factors (PRGF) from platelet-rich plasma favors human and canine ASC survival, proliferation, and delaying human ASC senescence and autophagocytosis in comparison with serum-containing cultures. In addition, canine and human-derived ASCs efficiently differentiate into osteocytes, adipocytes, or chondrocytes in the presence of PRGF. PRGF treatment induces phosphorylation of AKT preventing ASC death induced by lethal concentrations of hydrogen peroxide. Indeed, AKT inhibition abolished the PRGF apoptosis prevention in ASC exposed to 100  μ M of hydrogen peroxide. Here, we show that canine ASCs respond to PRGF stimulus similarly to the human cells regarding cell survival and differentiation postulating the use of dogs as a suitable translational model. Overall, PRGF would be employed as a serum substitute for mesenchymal stem cell amplification to improve cell differentiation and as a preconditioning agent to prevent oxidative cell death.

  14. Plasma Rich in Growth Factors Induces Cell Proliferation, Migration, Differentiation, and Cell Survival of Adipose-Derived Stem Cells

    Maravillas Mellado-López

    2017-01-01

    Full Text Available Adipose-derived stem cells (ASCs are a promising therapeutic alternative for tissue repair in various clinical applications. However, restrictive cell survival, differential tissue integration, and undirected cell differentiation after transplantation in a hostile microenvironment are complications that require refinement. Plasma rich in growth factors (PRGF from platelet-rich plasma favors human and canine ASC survival, proliferation, and delaying human ASC senescence and autophagocytosis in comparison with serum-containing cultures. In addition, canine and human-derived ASCs efficiently differentiate into osteocytes, adipocytes, or chondrocytes in the presence of PRGF. PRGF treatment induces phosphorylation of AKT preventing ASC death induced by lethal concentrations of hydrogen peroxide. Indeed, AKT inhibition abolished the PRGF apoptosis prevention in ASC exposed to 100 μM of hydrogen peroxide. Here, we show that canine ASCs respond to PRGF stimulus similarly to the human cells regarding cell survival and differentiation postulating the use of dogs as a suitable translational model. Overall, PRGF would be employed as a serum substitute for mesenchymal stem cell amplification to improve cell differentiation and as a preconditioning agent to prevent oxidative cell death.

  15. Long-term survival of transplanted allogeneic cells engineered to express a T cell chemorepellent.

    Papeta, Natalia; Chen, Tao; Vianello, Fabrizio; Gererty, Lyle; Malik, Ashish; Mok, Ying-Ting; Tharp, William G; Bagley, Jessamyn; Zhao, Guiling; Stevceva, Liljana; Yoon, Victor; Sykes, Megan; Sachs, David; Iacomini, John; Poznansky, Mark C

    2007-01-27

    Alloantigen specific T cells have been shown to be required for allograft rejection. The chemokine, stromal cell derived factor-1 (SDF-1) at high concentration, has been shown to act as a T-cell chemorepellent and abrogate T-cell infiltration into a site of antigen challenge in vivo via a mechanism termed fugetaxis or chemorepulsion. We postulated that this mechanism could be exploited therapeutically and that allogeneic cells engineered to express a chemorepellent protein would not be rejected. Allogeneic murine insulinoma beta-TC3 cells and primary islets from BALB/C mice were engineered to constitutively secrete differential levels of SDF-1 and transplanted into allogeneic diabetic C57BL/6 mice. Rejection was defined as the permanent return of hyperglycemia and was correlated with the level of T-cell infiltration. The migratory response of T-cells to SDF-1 was also analyzed by transwell migration assay and time-lapse videomicroscopy. The cytotoxicity of cytotoxic T cell (CTLs) against beta-TC3 cells expressing high levels of SDF-1 was measured in standard and modified chromium-release assays in order to determine the effect of CTL migration on killing efficacy. Control animals rejected allogeneic cells and remained diabetic. In contrast, high level SDF-1 production by transplanted cells resulted in increased survival of the allograft and a significant reduction in blood glucose levels and T-cell infiltration into the transplanted tissue. This is the first demonstration of a novel approach that exploits T-cell chemorepulsion to induce site specific immune isolation and thereby overcomes allograft rejection without the use of systemic immunosuppression.

  16. Calcium-independent phospholipase A₂, group VIA, is critical for RPE cell survival

    Kolko, Miriam; Vohra, Rupali; Westlund, Barbro S.

    2014-01-01

    PURPOSE: To investigate the significance of calcium-independent phospholipase A₂, group VIA (iPLA2-VIA), in RPE cell survival following responses to sodium iodate (SI) in cell cultures. METHODS: The human retinal pigment epithelium (RPE) cell line (ARPE-19) cells and primary mouse-RPE cultures were...

  17. Cell Survival and DNA Damage in Normal Prostate Cells Irradiated Out-of-Field.

    Shields, L

    2014-10-31

    Interest in out-of-field radiation dose has been increasing with the introduction of new techniques, such as volumetric modulated arc therapy (VMAT). These new techniques offer superior conformity of high-dose regions to the target compared to conventional techniques, however more normal tissue is exposed to low-dose radiation with VMAT. There is a potential increase in radiobiological effectiveness associated with lower energy photons delivered during VMAT as normal cells are exposed to a temporal change in incident photon energy spectrum. During VMAT deliveries, normal cells can be exposed to the primary radiation beam, as well as to transmission and scatter radiation. The impact of low-dose radiation, radiation-induced bystander effect and change in energy spectrum on normal cells are not well understood. The current study examined cell survival and DNA damage in normal prostate cells after exposure to out-of-field radiation both with and without the transfer of bystander factors. The effect of a change in energy spectrum out-of-field compared to in-field was also investigated. Prostate cancer (LNCaP) and normal prostate (PNT1A) cells were placed in-field and out-of-field, respectively, with the PNT1A cells being located 1 cm from the field edge when in-field cells were being irradiated with 2 Gy. Clonogenic and γ-H2AX assays were performed postirradiation to examine cell survival and DNA damage. The assays were repeated when bystander factors from the LNCaP cells were transferred to the PNT1A cells and also when the PNT1A cells were irradiated in-field to a different energy spectrum. An average out-of-field dose of 10.8 ± 4.2 cGy produced a significant reduction in colony volume and increase in the number of γ-H2AX foci\\/cell in the PNT1A cells compared to the sham-irradiated control cells. An adaptive response was observed in the PNT1A cells having first received a low out-of-field dose and then the bystander factors. The PNT1A cells showed a significant

  18. MHC-I modulation due to changes in tumor cell metabolism regulates tumor sensitivity to CTL and NK cells

    Catalán, Elena; Charni, Seyma; Jaime, Paula; Aguiló, Juan Ignacio; Enríquez, José Antonio; Naval, Javier; Pardo, Julián; Villalba, Martín; Anel, Alberto

    2015-01-01

    Tumor cells have a tendency to use glucose fermentation to obtain energy instead of mitochondrial oxidative phosphorylation (OXPHOS). We demonstrated that this phenotype correlated with loss of ERK5 expression and with reduced MHC class I expression. Consequently, tumor cells could evade cytotoxic T lymphocyte (CTL)-mediated immune surveillance, but also increase their sensitivity to natural killer (NK) cells. These outcomes were evaluated using two cellular models: leukemic EL4 cells and L929 transformed fibroblasts and their derived ρ° cell lines, which lack mitochondrial DNA. We have also used a L929 cell sub-line that spontaneously lost matrix attachment (L929dt), reminiscent of metastasis generation, that also downregulated MHC-I and ERK5 expression. MHC-I expression is lower in ρ° cells than in the parental cell lines, but they were equally sensitive to CTL. On the contrary, ρ° cells were more sensitive to activated NK cells than parental cells. On the other hand, L929dt cells were resistant to CTL and NK cells, showed reduced viability when forced to perform OXPHOS, and surviving cells increased MHC-I expression and became sensitive to CTL. The present results suggest that when the reduction in MHC-I levels in tumor cells due to glycolytic metabolism is partial, the increase in sensitivity to NK cells seems to predominate. However, when tumor cells completely lose MHC-I expression, the combination of treatments that increase OXPHOS with CTL-mediated immunotherapy could be a promising therapeutic approach. PMID:25949869

  19. MHC-I modulation due to changes in tumor cell metabolism regulates tumor sensitivity to CTL and NK cells.

    Catalán, Elena; Charni, Seyma; Jaime, Paula; Aguiló, Juan Ignacio; Enríquez, José Antonio; Naval, Javier; Pardo, Julián; Villalba, Martín; Anel, Alberto

    2015-01-01

    Tumor cells have a tendency to use glucose fermentation to obtain energy instead of mitochondrial oxidative phosphorylation (OXPHOS). We demonstrated that this phenotype correlated with loss of ERK5 expression and with reduced MHC class I expression. Consequently, tumor cells could evade cytotoxic T lymphocyte (CTL)-mediated immune surveillance, but also increase their sensitivity to natural killer (NK) cells. These outcomes were evaluated using two cellular models: leukemic EL4 cells and L929 transformed fibroblasts and their derived ρ° cell lines, which lack mitochondrial DNA. We have also used a L929 cell sub-line that spontaneously lost matrix attachment (L929dt), reminiscent of metastasis generation, that also downregulated MHC-I and ERK5 expression. MHC-I expression is lower in ρ° cells than in the parental cell lines, but they were equally sensitive to CTL. On the contrary, ρ° cells were more sensitive to activated NK cells than parental cells. On the other hand, L929dt cells were resistant to CTL and NK cells, showed reduced viability when forced to perform OXPHOS, and surviving cells increased MHC-I expression and became sensitive to CTL. The present results suggest that when the reduction in MHC-I levels in tumor cells due to glycolytic metabolism is partial, the increase in sensitivity to NK cells seems to predominate. However, when tumor cells completely lose MHC-I expression, the combination of treatments that increase OXPHOS with CTL-mediated immunotherapy could be a promising therapeutic approach.

  20. Oral Gingival Cell Cigarette Smoke Exposure Induces Muscle Cell Metabolic Disruption

    Andrea C. Baeder

    2016-01-01

    Full Text Available Cigarette smoke exposure compromises health through damaging multiple physiological systems, including disrupting metabolic function. The purpose of this study was to determine the role of oral gingiva in mediating the deleterious metabolic effects of cigarette smoke exposure on skeletal muscle metabolic function. Using an in vitro conditioned medium cell model, skeletal muscle cells were incubated with medium from gingival cells treated with normal medium or medium containing suspended cigarette smoke extract (CSE. Following incubation of muscle cells with gingival cell conditioned medium, muscle cell mitochondrial respiration and insulin signaling and action were determined as an indication of overall muscle metabolic health. Skeletal muscle cells incubated with conditioned medium of CSE-treated gingival cells had a profound reduction in mitochondrial respiration and respiratory control. Furthermore, skeletal muscle cells had a greatly reduced response in insulin-stimulated Akt phosphorylation and glycogen synthesis. Altogether, these results provide a novel perspective on the mechanism whereby cigarette smoke affects systemic metabolic function. In conclusion, we found that oral gingival cells treated with CSE create an altered milieu that is sufficient to both disrupted skeletal muscle cell mitochondrial function and insulin sensitivity.

  1. Metabolism and the Control of Cell Fate Decisions and Stem Cell Renewal

    Ito, Kyoko; Ito, Keisuke

    2016-01-01

    Although the stem cells of various tissues remain in the quiescent state to maintain their undifferentiated state, they also undergo cell divisions as required, and if necessary, even a single stem cell is able to provide for lifelong tissue homeostasis. Stem cell populations are precisely controlled by the balance between their symmetric and asymmetric divisions, with their division patterns determined by whether the daughter cells involved retain their self-renewal capacities. Recent studies have reported that metabolic pathways and the distribution of mitochondria are regulators of the division balance of stem cells and that metabolic defects can shift division balance toward symmetric commitment, which leads to stem cell exhaustion. It has also been observed that in asymmetric division, old mitochondria, which are central metabolic organelles, are segregated to the daughter cell fated to cell differentiation, whereas in symmetric division, young and old mitochondria are equally distributed between both daughter cells. Thus, metabolism and mitochondrial biology play important roles in stem cell fate decisions. As these decisions directly affect tissue homeostasis, understanding their regulatory mechanisms in the context of cellular metabolism is critical. PMID:27482603

  2. Survival of transfused red blood cells: In vivo compatibility testing with chromium-51

    Dharkar, D.D.; Pineda, A.A.

    1983-01-01

    The /sup 51/Cr red cell survival test and specific test for measurement of the disappearance rate of labeled red cells. This procedure can be used for the assessment of red cell compatibility testing in vivo. The authors recommend that more routine transfusions as well as ''difficult'' transfusions be monitored by /sup 51/Cr in vivo compatibility testing before the actual transfusions, so that more consistent and reliable survival values are achieved

  3. Metabolic reprogramming for producing energy and reducing power in fumarate hydratase null cells from hereditary leiomyomatosis renal cell carcinoma.

    Youfeng Yang

    Full Text Available Fumarate hydratase (FH-deficient kidney cancer undergoes metabolic remodeling, with changes in mitochondrial respiration, glucose, and glutamine metabolism. These changes represent multiple biochemical adaptations in glucose and fatty acid metabolism that supports malignant proliferation. However, the metabolic linkages between altered mitochondrial function, nucleotide biosynthesis and NADPH production required for proliferation and survival have not been elucidated. To characterize the alterations in glycolysis, the Krebs cycle and the pentose phosphate pathways (PPP that either generate NADPH (oxidative or do not (non-oxidative, we utilized [U-(13C]-glucose, [U-(13C,(15N]-glutamine, and [1,2- (13C2]-glucose tracers with mass spectrometry and NMR detection to track these pathways, and measured the oxygen consumption rate (OCR and extracellular acidification rate (ECAR of growing cell lines. This metabolic reprogramming in the FH null cells was compared to cells in which FH has been restored. The FH null cells showed a substantial metabolic reorganization of their intracellular metabolic fluxes to fulfill their high ATP demand, as observed by a high rate of glucose uptake, increased glucose turnover via glycolysis, high production of glucose-derived lactate, and low entry of glucose carbon into the Krebs cycle. Despite the truncation of the Krebs cycle associated with inactivation of fumarate hydratase, there was a small but persistent level of mitochondrial respiration, which was coupled to ATP production from oxidation of glutamine-derived α-ketoglutarate through to fumarate. [1,2- (13C2]-glucose tracer experiments demonstrated that the oxidative branch of PPP initiated by glucose-6-phosphate dehydrogenase activity is preferentially utilized for ribose production (56-66% that produces increased amounts of ribose necessary for growth and NADPH. Increased NADPH is required to drive reductive carboxylation of α-ketoglutarate and fatty acid

  4. Role of innate lymphoid cells in obesity and metabolic disease

    Saetang, Jirakrit; Sangkhathat, Surasak

    2018-01-01

    The immune system has previously been demonstrated to be associated with the pathophysiological development of metabolic abnormalities. However, the mechanisms linking immunity to metabolic disease remain to be fully elucidated. It has previously been suggested that innate lymphoid cells (ILCs) may be involved in the progression of numerous types of metabolic diseases as these cells act as suppressors and promoters for obesity and associated conditions, and are particularly involved in adipose tissue inflammation, which is a major feature of metabolic imbalance. Group 2 ILCs (ILC2s) have been revealed as anti-obese immune regulators by secreting anti-inflammatory cytokines and promoting the polarization of M2 macrophages, whereas group 1 ILCs (ILC1s), including natural killer cells, may promote adipose tissue inflammation via production of interferon-γ, which in turn polarizes macrophages toward the M1 type. The majority of studies to date have demonstrated the pathological association between ILCs and obesity in the context of adipose tissue inflammation, whereas the roles of ILCs in other organs which participate in obesity development have not been fully characterized. Therefore, identifying the roles of all types of ILCs as central components mediating obesity-associated inflammation, is of primary concern, and may lead to the discovery of novel preventative and therapeutic interventions. PMID:29138853

  5. Erythrokinetics, ferrokinetics and red cell survival in sickle cell anaemia under subtropical climatic conditions

    Cardenas, R.

    1975-01-01

    Ferrokinetic parameters were evaluated with 59 Fe and red-cell survival with 51 Cr by classical techniques in a total of 17 patients with sickle-cell disease. The mean plasma 59 Fe half-disappearance time in these patients was 29.5 min as compared with a normal value of 92 min, and the t1/2 51 Cr 8.0 days as compared with a normal value of 26.0 days. The mean red-cell iron turnover rate was elevated to 9 times normal. The increased destruction of red cells appeared to take place predominantly, though not entirely, in the spleen. Eight of the 17 patients studied were identified as having intercurrent complications, but these did not significantly affect the results of the investigations. A group of 5 boys in whom the red-cell iron turnover rate was elevated to a lesser degree than in the other patients were subjected to more detailed studies of plasma 59 Fe clearance with particular reference to ineffective erythropoiesis. In these patients, the plasma 59 Fe clearance curves showed precocious humps characteristic of ineffective erythropoiesis. Detailed analysis of the results indicated ineffective erythropoiesis corresponding to 3.6, 16.0, 22.6, 32.0 and 50.0 % of the iron initially taken up by the bone marrow. It is concluded that while the anaemia in most patients with sickle-cell disease is mainly due to shortened survival of the circulating red cells, with increased destruction of red cells in the spleen, ineffective erythropoiesis may none the less be an important factor determining the actual degree of this anaemia

  6. Tumor microenvironment derived exosomes pleiotropically modulate cancer cell metabolism.

    Zhao, Hongyun; Yang, Lifeng; Baddour, Joelle; Achreja, Abhinav; Bernard, Vincent; Moss, Tyler; Marini, Juan C; Tudawe, Thavisha; Seviour, Elena G; San Lucas, F Anthony; Alvarez, Hector; Gupta, Sonal; Maiti, Sourindra N; Cooper, Laurence; Peehl, Donna; Ram, Prahlad T; Maitra, Anirban; Nagrath, Deepak

    2016-02-27

    Cancer-associated fibroblasts (CAFs) are a major cellular component of tumor microenvironment in most solid cancers. Altered cellular metabolism is a hallmark of cancer, and much of the published literature has focused on neoplastic cell-autonomous processes for these adaptations. We demonstrate that exosomes secreted by patient-derived CAFs can strikingly reprogram the metabolic machinery following their uptake by cancer cells. We find that CAF-derived exosomes (CDEs) inhibit mitochondrial oxidative phosphorylation, thereby increasing glycolysis and glutamine-dependent reductive carboxylation in cancer cells. Through 13C-labeled isotope labeling experiments we elucidate that exosomes supply amino acids to nutrient-deprived cancer cells in a mechanism similar to macropinocytosis, albeit without the previously described dependence on oncogenic-Kras signaling. Using intra-exosomal metabolomics, we provide compelling evidence that CDEs contain intact metabolites, including amino acids, lipids, and TCA-cycle intermediates that are avidly utilized by cancer cells for central carbon metabolism and promoting tumor growth under nutrient deprivation or nutrient stressed conditions.

  7. Tumor microenvironment derived exosomes pleiotropically modulate cancer cell metabolism

    Zhao, Hongyun; Yang, Lifeng; Baddour, Joelle; Achreja, Abhinav; Bernard, Vincent; Moss, Tyler; Marini, Juan C; Tudawe, Thavisha; Seviour, Elena G; San Lucas, F Anthony; Alvarez, Hector; Gupta, Sonal; Maiti, Sourindra N; Cooper, Laurence; Peehl, Donna; Ram, Prahlad T; Maitra, Anirban; Nagrath, Deepak

    2016-01-01

    Cancer-associated fibroblasts (CAFs) are a major cellular component of tumor microenvironment in most solid cancers. Altered cellular metabolism is a hallmark of cancer, and much of the published literature has focused on neoplastic cell-autonomous processes for these adaptations. We demonstrate that exosomes secreted by patient-derived CAFs can strikingly reprogram the metabolic machinery following their uptake by cancer cells. We find that CAF-derived exosomes (CDEs) inhibit mitochondrial oxidative phosphorylation, thereby increasing glycolysis and glutamine-dependent reductive carboxylation in cancer cells. Through 13C-labeled isotope labeling experiments we elucidate that exosomes supply amino acids to nutrient-deprived cancer cells in a mechanism similar to macropinocytosis, albeit without the previously described dependence on oncogenic-Kras signaling. Using intra-exosomal metabolomics, we provide compelling evidence that CDEs contain intact metabolites, including amino acids, lipids, and TCA-cycle intermediates that are avidly utilized by cancer cells for central carbon metabolism and promoting tumor growth under nutrient deprivation or nutrient stressed conditions. DOI: http://dx.doi.org/10.7554/eLife.10250.001 PMID:26920219

  8. Metformin Decouples Phospholipid Metabolism in Breast Cancer Cells.

    Tim A D Smith

    Full Text Available The antidiabetic drug metformin, currently undergoing trials for cancer treatment, modulates lipid and glucose metabolism both crucial in phospholipid synthesis. Here the effect of treatment of breast tumour cells with metformin on phosphatidylcholine (PtdCho metabolism which plays a key role in membrane synthesis and intracellular signalling has been examined.MDA-MB-468, BT474 and SKBr3 breast cancer cell lines were treated with metformin and [3H-methyl]choline and [14C(U]glucose incorporation and lipid accumulation determined in the presence and absence of lipase inhibitors. Activities of choline kinase (CK, CTP:phosphocholine cytidylyl transferase (CCT and PtdCho-phospholipase C (PLC were also measured. [3H] Radiolabelled metabolites were determined using thin layer chromatography.Metformin-treated cells exhibited decreased formation of [3H]phosphocholine but increased accumulation of [3H]choline by PtdCho. CK and PLC activities were decreased and CCT activity increased by metformin-treatment. [14C] incorporation into fatty acids was decreased and into glycerol was increased in breast cancer cells treated with metformin incubated with [14C(U]glucose.This is the first study to show that treatment of breast cancer cells with metformin induces profound changes in phospholipid metabolism.

  9. Out-of-Field Cell Survival Following Exposure to Intensity-Modulated Radiation Fields

    Butterworth, Karl T.; McGarry, Conor K.; Trainor, Colman; O'Sullivan, Joe M.; Hounsell, Alan R.; Prise, Kevin M.

    2011-01-01

    Purpose: To determine the in-field and out-of-field cell survival of cells irradiated with either primary field or scattered radiation in the presence and absence of intercellular communication. Methods and Materials: Cell survival was determined by clonogenic assay in human prostate cancer (DU145) and primary fibroblast (AGO1552) cells following exposure to different field configurations delivered using a 6-MV photon beam produced with a Varian linear accelerator. Results: Nonuniform dose distributions were delivered using a multileaf collimator (MLC) in which half of the cell population was shielded. Clonogenic survival in the shielded region was significantly lower than that predicted from the linear quadratic model. In both cell lines, the out-of-field responses appeared to saturate at 40%-50% survival at a scattered dose of 0.70 Gy in DU-145 cells and 0.24 Gy in AGO1522 cells. There was an approximately eightfold difference in the initial slopes of the out-of-field response compared with the α-component of the uniform field response. In contrast, cells in the exposed part of the field showed increased survival. These observations were abrogated by direct physical inhibition of cellular communication and by the addition of the inducible nitric oxide synthase inhibitor aminoguanidine known to inhibit intercellular bystander effects. Additional studies showed the proportion of cells irradiated and dose delivered to the shielded and exposed regions of the field to impact on response. Conclusions: These data demonstrate out-of-field effects as important determinants of cell survival following exposure to modulated irradiation fields with cellular communication between differentially irradiated cell populations playing an important role. Validation of these observations in additional cell models may facilitate the refinement of existing radiobiological models and the observations considered important determinants of cell survival.

  10. Transitional-2 B cells acquire regulatory function during tolerance induction and contribute to allograft survival.

    Moreau, Aurélie; Blair, Paul A; Chai, Jian-Guo; Ratnasothy, Kulachelvy; Stolarczyk, Emilie; Alhabbab, Rowa; Rackham, Chloe L; Jones, Peter M; Smyth, Lesley; Elgueta, Raul; Howard, Jane K; Lechler, Robert I; Lombardi, Giovanna

    2015-03-01

    In humans, tolerance to renal transplants has been associated with alterations in B-cell gene transcription and maintenance of the numbers of circulating transitional B cells. Here, we use a mouse model of transplantation tolerance to investigate the contribution of B cells to allograft survival. We demonstrate that transfer of B cells from mice rendered tolerant to MHC class I mismatched skin grafts can prolong graft survival in a dose-dependent and antigen-specific manner to a degree similar to that afforded by graft-specific regulatory T (Treg) cells. Tolerance in this model was associated with an increase in transitional-2 (T2) B cells. Only T2 B cells from tolerized mice, not naïve T2 nor alloantigen experienced T2, were capable of prolonging skin allograft survival, and suppressing T-cell activation. Tolerized T2 B cells expressed lower levels of CD86, increased TIM-1, and demonstrated a preferential survival in vivo. Furthermore, we demonstrate a synergistic effect between tolerized B cells and graft-specific Treg cells. IL-10 production by T2 B cells did not contribute to tolerance, as shown by transfer of B cells from IL-10(-/-) mice. These results suggest that T2 B cells in tolerant patients may include a population of regulatory B cells that directly inhibit graft rejection. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Intracellular contacts - effect of survival curve of mammal cells on the Dq value

    Durand, R.E.; Sutherland, R.M.

    1980-01-01

    Survival increase is observed in cells of the Chinese hamster of the V79-171 line which grow in the composition of multicell spheroids as compared with the survival after irradiation in a single state. The ratio of the Dsub(q) cell value in the composition of spheroids to Dsub(q) of separately growing cells increases as the mitotic cycle proceeds from the minimum value of 1.3 for cells in the Gi phase to the maximum value of 2.2 for cells in a late S-phase. The increase of survival during growth in the composition of spheroids is not characteristic for all cell types. Only a part of cultured MNNG-mutants of cells of the V79-171 Chinese hamster reveal radiomodifying effect of cell contact acting [ru

  12. Roles of StearoylCoA Desaturase-1 in the Regulation of Cancer Cell Growth, Survival and Tumorigenesis

    Igal, R. Ariel [Department of Nutritional Sciences and Rutgers Center for Lipid Research, Rutgers, the State University of New Jersey, 96 Lipman Drive, New Brunswick, NJ 08901 (United States)

    2011-05-20

    The development and maintenance of defining features of cancer, such as unremitting cell proliferation, evasion of programmed cell death, and the capacity for colonizing local tissues and distant organs, demand a massive production of structural, signaling and energy-storing lipid biomolecules of appropriate fatty acid composition. Due to constitutive activation of fatty acid biosynthesis, cancer cell lipids are enriched with saturated (SFA) and, in particular, monounsaturated fatty acids (MUFA), which are generated by StearoylCoA desaturase-1, the main enzyme that transforms SFA into MUFA. An increasing number of experimental and epidemiological studies suggest that high levels of SCD1 activity is a major factor in establishing the biochemical and metabolic perturbations that favors the oncogenic process. This review examines evidence that suggests the critical implication of SCD1 in the modulation of multiple biological mechanisms, specifically lipid biosynthesis and proliferation and survival signaling pathways that contribute to the development and progression of cancer.

  13. Roles of StearoylCoA Desaturase-1 in the Regulation of Cancer Cell Growth, Survival and Tumorigenesis

    Igal, R. Ariel

    2011-01-01

    The development and maintenance of defining features of cancer, such as unremitting cell proliferation, evasion of programmed cell death, and the capacity for colonizing local tissues and distant organs, demand a massive production of structural, signaling and energy-storing lipid biomolecules of appropriate fatty acid composition. Due to constitutive activation of fatty acid biosynthesis, cancer cell lipids are enriched with saturated (SFA) and, in particular, monounsaturated fatty acids (MUFA), which are generated by StearoylCoA desaturase-1, the main enzyme that transforms SFA into MUFA. An increasing number of experimental and epidemiological studies suggest that high levels of SCD1 activity is a major factor in establishing the biochemical and metabolic perturbations that favors the oncogenic process. This review examines evidence that suggests the critical implication of SCD1 in the modulation of multiple biological mechanisms, specifically lipid biosynthesis and proliferation and survival signaling pathways that contribute to the development and progression of cancer

  14. Survival Analysis of F98 Glioma Rat Cells Following Minibeam or Broad-Beam Synchrotron Radiation Therapy

    Gil, Silvia; Sarun, Sukhéna; Biete, Albert; Prezado, Yolanda; Sabés, Manel

    2011-01-01

    In the quest of a curative radiotherapy treatment for gliomas new delivery modes are being explored. At the Biomedical Beamline of the European Synchrotron Radiation Facility (ESRF), a new spatially-fractionated technique, called Minibeam Radiation Therapy (MBRT) is under development. The aim of this work is to compare the effectiveness of MBRT and broad-beam (BB) synchrotron radiation to treat F98 glioma rat cells. A dose escalation study was performed in order to delimit the range of doses where a therapeutic effect could be expected. These results will help in the design and optimization of the forthcoming in vivo studies at the ESRF. Two hundred thousand F98 cells were seeded per well in 24-well plates, and incubated for 48 hours before being irradiated with spatially fractionated and seamless synchrotron x-rays at several doses. The percentage of each cell population (alive, early apoptotic and dead cells, where either late apoptotic as necrotic cells are included) was assessed by flow cytometry 48 hours after irradiation, whereas the metabolic activity of surviving cells was analyzed on days 3, 4, and 9 post-irradiation by using QBlue test. The endpoint (or threshold dose from which an important enhancement in the effectiveness of both radiation treatments is achieved) obtained by flow cytometry could be established just before 12 Gy in the two irradiation schemes, whilst the endpoints assessed by the QBlue reagent, taking into account the cell recovery, were set around 18 Gy in both cases. In addition, flow cytometric analysis pointed at a larger effectiveness for minibeams, due to the higher proportion of early apoptotic cells. When the valley doses in MBRT equal the dose deposited in the BB scheme, similar cell survival ratio and cell recovery were observed. However, a significant increase in the number of early apoptotic cells were found 48 hours after the minibeam radiation in comparison with the seamless mode

  15. Genome scale metabolic modeling of cancer

    Nilsson, Avlant; Nielsen, Jens

    2017-01-01

    of metabolism which allows simulation and hypotheses testing of metabolic strategies. It has successfully been applied to many microorganisms and is now used to study cancer metabolism. Generic models of human metabolism have been reconstructed based on the existence of metabolic genes in the human genome......Cancer cells reprogram metabolism to support rapid proliferation and survival. Energy metabolism is particularly important for growth and genes encoding enzymes involved in energy metabolism are frequently altered in cancer cells. A genome scale metabolic model (GEM) is a mathematical formalization...

  16. Pancreatic cancer circulating tumour cells express a cell motility gene signature that predicts survival after surgery

    Sergeant, Gregory; Eijsden, Rudy van; Roskams, Tania; Van Duppen, Victor; Topal, Baki

    2012-01-01

    Most cancer deaths are caused by metastases, resulting from circulating tumor cells (CTC) that detach from the primary cancer and survive in distant organs. The aim of the present study was to develop a CTC gene signature and to assess its prognostic relevance after surgery for pancreatic ductal adenocarcinoma (PDAC). Negative depletion fluorescence activated cell sorting (FACS) was developed and validated with spiking experiments using cancer cell lines in whole human blood samples. This FACS-based method was used to enrich for CTC from the blood of 10 patients who underwent surgery for PDAC. Total RNA was isolated from 4 subgroup samples, i.e. CTC, haematological cells (G), original tumour (T), and non-tumoural pancreatic control tissue (P). After RNA quality control, samples of 6 patients were eligible for further analysis. Whole genome microarray analysis was performed after double linear amplification of RNA. ‘Ingenuity Pathway Analysis’ software and AmiGO were used for functional data analyses. A CTC gene signature was developed and validated with the nCounter system on expression data of 78 primary PDAC using Cox regression analysis for disease-free (DFS) and overall survival (OS). Using stringent statistical analysis, we retained 8,152 genes to compare expression profiles of CTC vs. other subgroups, and found 1,059 genes to be differentially expressed. The pathway with the highest expression ratio in CTC was p38 mitogen-activated protein kinase (p38 MAPK) signaling, known to be involved in cancer cell migration. In the p38 MAPK pathway, TGF-β1, cPLA2, and MAX were significantly upregulated. In addition, 9 other genes associated with both p38 MAPK signaling and cell motility were overexpressed in CTC. High co-expression of TGF-β1 and our cell motility panel (≥ 4 out of 9 genes for DFS and ≥ 6 out of 9 genes for OS) in primary PDAC was identified as an independent predictor of DFS (p=0.041, HR (95% CI) = 1.885 (1.025 – 3.559)) and OS (p=0.047, HR

  17. Early NK Cell Reconstitution Predicts Overall Survival in T-Cell Replete Allogeneic Hematopoietic Stem Cell Transplantation

    Minculescu, Lia; Marquart, Hanne Vibeke; Friis, Lone Smidstrups

    2016-01-01

    Early immune reconstitution plays a critical role in clinical outcome after allogeneic hematopoietic stem cell transplantation (HSCT). Natural killer (NK) cells are the first lymphocytes to recover after transplantation and are considered powerful effector cells in HSCT. We aimed to evaluate...... the clinical impact of early NK cell recovery in T-cell replete transplant recipients. Immune reconstitution was studied in 298 adult patients undergoing HSCT for acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL) and myelodysplastic syndrome (MDS) from 2005 to 2013. In multivariate analysis NK...... cell numbers day 30 (NK30) >150cells/µL were independently associated with superior overall survival (hazard ratio 0.79, 95% confidence interval 0.66-0.95, p=0.01). Cumulative incidence analyses showed that patients with NK30 >150cells/µL had significantly less transplant related mortality (TRM), p=0...

  18. Overexpression of FABP3 inhibits human bone marrow derived mesenchymal stem cell proliferation but enhances their survival in hypoxia

    Wang, Suna; Zhou, Yifu; Andreyev, Oleg; Hoyt, Robert F.; Singh, Avneesh; Hunt, Timothy; Horvath, Keith A.

    2014-01-01

    Studying the proliferative ability of human bone marrow derived mesenchymal stem cells in hypoxic conditions can help us achieve the effective regeneration of ischemic injured myocardium. Cardiac-type fatty acid binding protein (FABP3) is a specific biomarker of muscle and heart tissue injury. This protein is purported to be involved in early myocardial development, adult myocardial tissue repair and responsible for the modulation of cell growth and proliferation. We have investigated the role of FABP3 in human bone marrow derived mesenchymal stem cells under ischemic conditions. MSCs from 12 donors were cultured either in standard normoxic or modified hypoxic conditions, and the differential expression of FABP3 was tested by quantitative RT PCR and western blot. We also established stable FABP3 expression in MSCs and searched for variation in cellular proliferation and differentiation bioprocesses affected by hypoxic conditions. We identified: (1) the FABP3 differential expression pattern in the MSCs under hypoxic conditions; (2) over-expression of FABP3 inhibited the growth and proliferation of the MSCs; however, improved their survival in low oxygen environments; (3) the cell growth factors and positive cell cycle regulation genes, such as PCNA, APC, CCNB1, CCNB2 and CDC6 were all down-regulated; while the key negative cell cycle regulation genes TP53, BRCA1, CASP3 and CDKN1A were significantly up-regulated in the cells with FABP3 overexpression. Our data suggested that FABP3 was up-regulated under hypoxia; also negatively regulated the cell metabolic process and the mitotic cell cycle. Overexpression of FABP3 inhibited cell growth and proliferation via negative regulation of the cell cycle and down-regulation of cell growth factors, but enhances cell survival in hypoxic or ischemic conditions. - Highlights: • FABP3 expression pattern was studied in 12 human hypoxic-MSCs. • FABP3 mRNA and proteins are upregulated in the MSCs under hypoxic conditions.

  19. Laminar shear stress inhibits endothelial cell metabolism via KLF2-mediated repression of PFKFB3

    Doddaballapur, Anuradha; Michalik, Katharina M.; Manavski, Yosif; Lucas, Tina; Houtkooper, Riekelt H.; You, Xintian; Chen, Wei; Zeiher, Andreas M.; Potente, Michael; Dimmeler, Stefanie; Boon, Reinier A.

    2015-01-01

    Cellular metabolism was recently shown to regulate endothelial cell phenotype profoundly. Whether the atheroprotective biomechanical stimulus elicited by laminar shear stress modulates endothelial cell metabolism is not known. Here, we show that laminar flow exposure reduced glucose uptake and

  20. Metabolic shift in lung alveolar cell mitochondria following acrolein exposure.

    Agarwal, Amit R; Yin, Fei; Cadenas, Enrique

    2013-11-15

    Acrolein, an α,β unsaturated electrophile, is an environmental pollutant released in ambient air from diesel exhausts and cooking oils. This study examines the role of acrolein in altering mitochondrial function and metabolism in lung-specific cells. RLE-6TN, H441, and primary alveolar type II (pAT2) cells were exposed to acrolein for 4 h, and its effect on mitochondrial oxygen consumption rates was studied by XF Extracellular Flux analysis. Low-dose acrolein exposure decreased mitochondrial respiration in a dose-dependent manner because of alteration in the metabolism of glucose in all the three cell types. Acrolein inhibited glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity, leading to decreased substrate availability for mitochondrial respiration in RLE-6TN, H441, and pAT2 cells; the reduced GAPDH activity was compensated in pAT2 cells by an increase in the activity of glucose-6-phosphate dehydrogenase, the regulatory control of the pentose phosphate pathway. The decrease in pyruvate from glucose metabolism resulted in utilization of alternative sources to support mitochondrial energy production: palmitate-BSA complex increased mitochondrial respiration in RLE-6TN and pAT2 cells. The presence of palmitate in alveolar cells for surfactant biosynthesis may prove to be the alternative fuel source for mitochondrial respiration. Accordingly, a decrease in phosphatidylcholine levels and an increase in phospholipase A2 activity were found in the alveolar cells after acrolein exposure. These findings have implications for understanding the decrease in surfactant levels frequently observed in pathophysiological situations with altered lung function following exposure to environmental toxicants.

  1. Optimal fractionation for the radiotherapy of tumour cells possessing wide-shouldered survival curves

    Wheldon, T.E.

    1979-01-01

    A recent publication (Zeitz, L., and McDonald, J.M., 1978, Br. J. Radiol., vol. 51, 637) has considered the use of in vitro survival curves in the evaluation of different treatment schedules. Several studies of oxygenated melanoma cell have demonstrated a wider than average shoulder width for the survival curves. It is possible that hypoxia reduces the width of this shoulder. Theoretical cell survival probabilities were calculated for each of the four treatment schedules considered by Zeitz and McDonald. The calculations were based on hypothetical survival curves for anoxic melanoma cells with the shoulder either fully retained or completely abolished. No allowance was made for either re-population or re-oxygenation. The advantage of small doses per fraction was demonstrated for both types of survival curve. Re-oxygenation during therapy could therefore mean that a non-uniform treatment schedule is the appropriate choice for this type of tumour. (U.K.)

  2. IR-induced autophagy plays a role in survival of HeLa cells

    Kang, Mi Young; Jang, Eun Yeong; Ryu, Tae Ho; Chung, Dong Min; Kim, Jin Hong; Kim, Jin Kyu

    2014-01-01

    Cells respond to stress with repair, or are diverted into irreversible cell cycle exit (senescence) or are eliminated through programmed cell death. There are two major morphologically distinctive forms of programmed cell death, apoptosis and autophagic cell death. Apoptosis contribute to cell death, whereas autophagy can play a dual role in mediating either cell survival or death in response to various stress stimuli. Here we analysed cellular responses induced by IR. The understanding of an appropriate cellular stress response is of crucial importance in foreseeing the cell fate. Apoptotic feagures were not detected in HeLa under our experimental irradiation condition. Autophagic cell death in HeLa may play an important role in cell protection and can result in cell survival

  3. Protein kinase activity of phosphoinositide 3-kinase regulates cytokine-dependent cell survival.

    Daniel Thomas

    Full Text Available The dual specificity protein/lipid kinase, phosphoinositide 3-kinase (PI3K, promotes growth factor-mediated cell survival and is frequently deregulated in cancer. However, in contrast to canonical lipid-kinase functions, the role of PI3K protein kinase activity in regulating cell survival is unknown. We have employed a novel approach to purify and pharmacologically profile protein kinases from primary human acute myeloid leukemia (AML cells that phosphorylate serine residues in the cytoplasmic portion of cytokine receptors to promote hemopoietic cell survival. We have isolated a kinase activity that is able to directly phosphorylate Ser585 in the cytoplasmic domain of the interleukin 3 (IL-3 and granulocyte macrophage colony stimulating factor (GM-CSF receptors and shown it to be PI3K. Physiological concentrations of cytokine in the picomolar range were sufficient for activating the protein kinase activity of PI3K leading to Ser585 phosphorylation and hemopoietic cell survival but did not activate PI3K lipid kinase signaling or promote proliferation. Blockade of PI3K lipid signaling by expression of the pleckstrin homology of Akt1 had no significant impact on the ability of picomolar concentrations of cytokine to promote hemopoietic cell survival. Furthermore, inducible expression of a mutant form of PI3K that is defective in lipid kinase activity but retains protein kinase activity was able to promote Ser585 phosphorylation and hemopoietic cell survival in the absence of cytokine. Blockade of p110α by RNA interference or multiple independent PI3K inhibitors not only blocked Ser585 phosphorylation in cytokine-dependent cells and primary human AML blasts, but also resulted in a block in survival signaling and cell death. Our findings demonstrate a new role for the protein kinase activity of PI3K in phosphorylating the cytoplasmic tail of the GM-CSF and IL-3 receptors to selectively regulate cell survival highlighting the importance of targeting

  4. Therapeutic potential of the metabolic modulator Metformin on osteosarcoma cancer stem-like cells.

    Paiva-Oliveira, Daniela I; Martins-Neves, Sara R; Abrunhosa, Antero J; Fontes-Ribeiro, Carlos; Gomes, Célia M F

    2018-01-01

    Osteosarcoma is the most common primary bone tumour appearing in children and adolescents. Recent studies demonstrate that osteosarcoma possesses a stem-like cell subset, so-called cancer stem-like cells, refractory to conventional chemotherapeutics and pointed out as responsible for relapses frequently observed in osteosarcoma patients. Here, we explored the therapeutic potential of Metformin on osteosarcoma stem-like cells, alone and as a chemosensitizer of doxorubicin. Stem-like cells were isolated from human osteosarcoma cell lines, MNNG/HOS and MG-63, using the sphere-forming assay. Metformin cytotoxicity alone and combined with doxorubicin were evaluated using MTT/BrdU assays. Protein levels of AMPK and AKT were evaluated by Western Blot. Cellular metabolic status was assessed based on [ 18 F]-FDG uptake and lactate production measurements. Sphere-forming efficiency and expression of pluripotency transcription factors analysed by qRT-PCR were tested as readout of Metformin effects on stemness features. Metformin induced a concentration-dependent decrease in the metabolic activity and proliferation of sphere-forming cells and improved doxorubicin-induced cytotoxicity. This drug also down-regulated the expression of master regulators of pluripotency (OCT4, SOX2, NANOG), and decreased spheres' self-renewal ability. Metformin effects on mitochondria led to the activation and phosphorylation of the energetic sensor AMPK along with an upregulation of the pro-survival AKT pathway in both cell populations. Furthermore, Metformin-induced mitochondrial stress increased [ 18 F]-FDG uptake and lactate production in parental cells but not in the quiescent stem-like cells, suggesting the inability of the latter to cope with the energy crisis induced by metformin. This preclinical study suggests that Metformin may be a potentially useful therapeutic agent and chemosensitizer of osteosarcoma stem-like cells to doxorubicin.

  5. Exploiting immune cell metabolic machinery for functional HIV cure and the prevention of inflammaging

    Palmer, Clovis S.; Palchaudhuri, Riya; Albargy, Hassan; Abdel-Mohsen, Mohamed; Crowe, Suzanne M.

    2018-01-01

    An emerging paradigm in immunology suggests that metabolic reprogramming and immune cell activation and functions are intricately linked. Viral infections, such as HIV infection, as well as cancer force immune cells to undergo major metabolic challenges. Cells must divert energy resources in order to mount an effective immune response. However, the fact that immune cells adopt specific metabolic programs to provide host defense against intracellular pathogens and how this metabolic shift impa...

  6. Ten-year survival of patients with oesophageal squamous cell ...

    patients with oesophageal SCC continues to be poor, with 5-year survival rates ranging from 26.2% to ... approach, and the cervico-thoraco-abdominal procedure. The .... abuse, a family history of any cancer, neo-adjuvant treatment, pathological ... Of the entire series, 72 patients (6.9%) underwent neo-adjuvant therapy, and.

  7. RNA metabolism in Xylella fastidiosa during cold adaptation and survival responses

    Fastidious plant pathogen Xylella fastidiosa has a reduced ability to adapt to cold temperatures, limiting persistence in perennial hosts, such as grapevine, growing in colder regions. RNA metabolism is an essential part of bacterial response to low temperature, including inducible expression of RNA...

  8. How to survive within a yeast colony?: Change metabolism or cope with stress?

    Čáp, M.; Váchová, Libuše; Palková, Z.

    2010-01-01

    Roč. 3, č. 2 (2010), s. 198-200 ISSN 1942-0889 R&D Projects: GA ČR GA204/08/0718; GA MŠk(CZ) LC531 Institutional research plan: CEZ:AV0Z50200510 Keywords : yeast colonies * stress defense and metabolic adaption * differentiation Subject RIV: EE - Microbiology, Virology

  9. CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production

    Khairnar, Vishal; Duhan, Vikas; Maney, Sathish Kumar; Honke, Nadine; Shaabani, Namir; Pandyra, Aleksandra A.; Seifert, Marc; Pozdeev, Vitaly; Xu, Haifeng C.; Sharma, Piyush; Baldin, Fabian; Marquardsen, Florian; Merches, Katja; Lang, Elisabeth; Kirschning, Carsten; Westendorf, Astrid M.; Häussinger, Dieter; Lang, Florian; Dittmer, Ulf; Küppers, Ralf; Recher, Mike; Hardt, Cornelia; Scheffrahn, Inka; Beauchemin, Nicole; Göthert, Joachim R.; Singer, Bernhard B.; Lang, Philipp A.; Lang, Karl S.

    2015-01-01

    B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1−/− mice limits the survival of B cells. During systemic infection with cytopathic vesicular stomatitis virus, Ceacam1−/− mice can barely induce neutralizing antibody responses and die early after infection. We find, therefore, that CEACAM1 is a crucial regulator of B-cell survival, influencing B-cell numbers and protective antiviral antibody responses. PMID:25692415

  10. Cell survival and chromosomal aberrations in CHO-K1 cells irradiated by carbon ions

    Czub, J. [Institute of Physics, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Banas, D. [Institute of Physics, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Holycross Cancer Center, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Blaszczyk, A. [Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun (Poland); Braziewicz, J. [Institute of Physics, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Holycross Cancer Center, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Buraczewska, I. [Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Choinski, J. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, 02-093 Warsaw (Poland); Gorak, U. [Institute of Experimental Physics, Warsaw University, ul. Hoza 69, 00-681 Warsaw (Poland); Jaskola, M.; Korman, A. [Andrzej Soltan Institute for Nuclear Studies, 05-400 Otwock-Swierk (Poland); Lankoff, A.; Lisowska, H. [Institute of Biology, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Lukaszek, A. [Institute of Experimental Physics, Warsaw University, ul. Hoza 69, 00-681 Warsaw (Poland); Main School of Fire Service, ul. Slowackiego 52/54, 01-629 Warsaw (Poland); Szeflinski, Z. [Institute of Experimental Physics, Warsaw University, ul. Hoza 69, 00-681 Warsaw (Poland)], E-mail: szef@fuw.edu.pl; Wojcik, A. [Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Institute of Biology, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland)

    2009-03-15

    Chinese hamster ovary CHO-K1 cells were exposed to high LET {sup 12}C-beam (LET: 830 keV/{mu}m) in the dose range of 0-6 Gy and to {sup 60}Co irradiation and the RBE value was obtained. Effects of {sup 12}C-beam exposure on cell survival and chromosomal aberrations were calculated. The chromosomal aberration data were fitted with linear equation. The distribution of aberration in cells was examined with a standard u-test and used to evaluate the data according to Poisson probabilities. The variance to the mean ratio {sigma}{sup 2}/Y and the dispersion index (u) were determined. Overdispersion was significant (p<0.05) when the value of u exceeded 1.96.

  11. DESHARKY: automatic design of metabolic pathways for optimal cell growth.

    Rodrigo, Guillermo; Carrera, Javier; Prather, Kristala Jones; Jaramillo, Alfonso

    2008-11-01

    The biological solution for synthesis or remediation of organic compounds using living organisms, particularly bacteria and yeast, has been promoted because of the cost reduction with respect to the non-living chemical approach. In that way, computational frameworks can profit from the previous knowledge stored in large databases of compounds, enzymes and reactions. In addition, the cell behavior can be studied by modeling the cellular context. We have implemented a Monte Carlo algorithm (DESHARKY) that finds a metabolic pathway from a target compound by exploring a database of enzymatic reactions. DESHARKY outputs a biochemical route to the host metabolism together with its impact in the cellular context by using mathematical models of the cell resources and metabolism. Furthermore, we provide the sequence of amino acids for the enzymes involved in the route closest phylogenetically to the considered organism. We provide examples of designed metabolic pathways with their genetic load characterizations. Here, we have used Escherichia coli as host organism. In addition, our bioinformatic tool can be applied for biodegradation or biosynthesis and its performance scales with the database size. Software, a tutorial and examples are freely available and open source at http://soft.synth-bio.org/desharky.html

  12. Effects of 3-styrylchromones on metabolic profiles and cell death in oral squamous cell carcinoma cells

    Hiroshi Sakagami

    2015-01-01

    Full Text Available 4H-1-benzopyran-4-ones (chromones are important naturally-distributing compounds. As compared with flavones, isoflavones and 2-styrylchromones, there are only few papers of 3-styrylchromones that have been published. We have previously reported that among fifteen 3-styrylchromone derivatives, three new synthetic compounds that have OCH3 group at the C-6 position of chromone ring, (E-3-(4-hydroxystyryl-6-methoxy-4H-chromen-4-one (compound 11, (E-6-methoxy-3-(4-methoxystyryl-4H-chromen-4-one (compound 4, (E-6-methoxy-3-(3,4,5-trimethoxystyryl-4H-chromen-4-one (compound 6 showed much higher cytotoxicities against four epithelial human oral squamous cell carcinoma (OSCC lines than human normal oral mesenchymal cells. In order to further confirm the tumor specificities of these compounds, we compared their cytotoxicities against both human epithelial malignant and non-malignant cells, and then investigated their effects on fine cell structures and metabolic profiles and cell death in human OSCC cell line HSC-2. Cytotoxicities of compounds 4, 6, 11 were assayed with MTT method. Fine cell structures were observed under transmission electron microscope. Cellular metabolites were extracted with methanol and subjected to CE-TOFMS analysis. Compounds 4, 6, 11 showed much weaker cytotoxicity against human oral keratinocyte and primary human gingival epithelial cells, as compared with HSC-2, confirming their tumor-specificity, whereas doxorubicin and 5-FU were highly cytotoxic to these normal epithelial cells, giving unexpectedly lower tumor-specificity. The most cytotoxic compound 11, induced the mitochondrial vacuolization, autophagy suppression followed by apoptosis induction, and changes in the metabolites involved in amino acid and glycerophospholipid metabolisms. Chemical modification of lead compound 11 may be a potential choice for designing new type of anticancer drugs.

  13. Effects of dietary phospholipid level in cobia (Rachycentron canadum) larvae: growth, survival, plasma lipids and enzymes of lipid metabolism.

    Niu, J; Liu, Y J; Tian, L X; Mai, K S; Yang, H J; Ye, C X; Zhu, Y

    2008-03-01

    A study was conducted to determine the effects of dietary phospholipid (PL) levels in cobia (Rachycentron canadum) larvae with regard to growth, survival, plasma lipids and enzymes of lipid metabolism. Fish with an average weight of 0.4 g were fed diets containing four levels of PL (0, 20, 40 and 80 g kg(-1)dry matter: purity 97%) for 42 days. Final body weight (FBW), weight gain (WG) and survival ratio were highest in the 8% PL diet group and mortality was highest in PL-free diet group. We examined the activities of lipoprotein lipase (LPL) and hepatic lipase (HL) in liver, lecithin-cholesterolacyltransferase (LCAT) in plasma as well as plasma lipids and lipoprotein. LCAT activity showed a decrease of more than two-fold in PL-supplemented diet groups compared with the PL-free diet group. HL activity was highest in the 8% PL diet group and the other three groups showed no difference. LPL activity was significantly higher in the PL-supplemented diet groups than in the PL-free diet group. The dietary intervention significantly increased plasma phospholipids and total cholesterol (TC) levels, and the higher free cholesterol (FC) level contributed to the TC level. However, the fish fed PL exhibited a significantly decreased plasma triglyceride (TG) level. The lipoprotein fractions were also affected significantly by the PL. The PL-supplemented diet groups had significantly higher high-density lipoprotein (HDL) compared with the PL-free diet group, but showed a marked decrease in very low-density lipoprotein (VLDL). The results suggested that PL could modify plasma lipoprotein metabolism and lipid profile, and that the optimal dietary PL level may well exceed 80 g kg(-1) for cobia larvae according to growth and survival.

  14. IL-15 expression on RA synovial fibroblasts promotes B cell survival.

    Marta Benito-Miguel

    Full Text Available INTRODUCTION: The purpose of this study was to examine the role of RA Synovial Fibroblast (RASFib IL-15 expression on B cell survival. METHODS: Magnetically sorted peripheral blood memory B cells from 15 healthy subjects were cocultured with RASFib. RESULTS: RASFib constitutively expressed membrane IL-15. Survival of isolated B cells cultured for 6 days, below 5%, was extended in coculture with RASFib to 52+/-8% (p<0.001. IL-15 neutralizing agents but not isotype controls, reduced this rate to 31+/-6% (p<0.05. Interestingly, rhIL-15 had no effect on isolated B cells but significantly increased their survival in coculture with RASFib. In parallel, B cell IL-15R chains were upregulated in cocultures. BAFF and VCAM-1, that are expressed on RASFib, were tested as potential candidates involved in upregulating B cell IL-15R. Culture of B cells in the presence of rhBAFF or rhVCAM-1 resulted in significantly increased survival, together with upregulation of all three IL-15R chains; in parallel, rhIL-15 potentiated the anti-apoptotic effect of BAFF and VCAM-1. Both BAFF and VCAM-1 neutralizing agents downmodulated the effect of RASFib on B cell survival and IL-15R expression. In parallel, rhIL-15 had a lower effect on the survival of B cells cocultured with RASFib in the presence of BAFF or VCAM-1 neutralizing agents. Peripheral blood B cells from 15 early RA patients demonstrated an upregulated IL-15R and increased survival in cocultures. CONCLUSION: IL-15 expression on RASFib significantly contributes to the anti-apoptotic effect of RASFib on B cells. IL-15 action is facilitated by BAFF and VCAM-1 expressed on RASFib, through an upregulation of IL-15R chains.

  15. Inhibition of human lung cancer cell proliferation and survival by wine

    2014-01-01

    Background Compounds of plant origin and food components have attracted scientific attention for use as agents for cancer prevention and treatment. Wine contains polyphenols that were shown to have anti-cancer and other health benefits. The survival pathways of Akt and extracellular signal-regulated kinase (Erk), and the tumor suppressor p53 are key modulators of cancer cell growth and survival. In this study, we examined the effects of wine on proliferation and survival of human Non-small cell lung cancer (NSCLC) cells and its effects on signaling events. Methods Human NSCLC adenocarcinoma A549 and H1299 cells were used. Cell proliferation was assessed by thymidine incorporation. Clonogenic assays were used to assess cell survival. Immunoblotting was used to examine total and phosphorylated levels of Akt, Erk and p53. Results In A549 cells red wine inhibited cell proliferation and reduced clonogenic survival at doses as low as 0.02%. Red wine significantly reduced basal and EGF-stimulated Akt and Erk phosphorylation while it increased the levels of total and phosphorylated p53 (Ser15). Control experiments indicated that the anti-proliferative effects of wine were not mediated by the associated contents of ethanol or the polyphenol resveratrol and were independent of glucose transport into cancer cells. White wine also inhibited clonogenic survival, albeit at a higher doses (0.5-2%), and reduced Akt phosphorylation. The effects of both red and white wine on Akt phosphorylation were also verified in H1299 cells. Conclusions Red wine inhibits proliferation of lung cancer cells and blocks clonogenic survival at low concentrations. This is associated with inhibition of basal and EGF-stimulated Akt and Erk signals and enhancement of total and phosphorylated levels of p53. White wine mediates similar effects albeit at higher concentrations. Our data suggest that wine may have considerable anti-tumour and chemoprevention properties in lung cancer and deserves further

  16. Cell cycle variation in x-ray survival for cells from spheroids measured by volume cell sorting

    Freyer, J.P.; Wilder, M.E.; Raju, M.R.

    1984-01-01

    Considerable work has been done studying the variation in cell survival as a function of cell cycle position for monolayers or single cells exposed to radiation. Little is known about the effects of multicellular growth on the relative radiation sensitivity of cells in different cell cycle stages. The authors have developed a new technique for measuring the response of cells, using volume cell sorting, which is rapid, non-toxic, and does not require cell synchronization. By combining this technique with selective spheroid dissociation,they have measured the age response of cells located at various depths in EMT6 and Colon 26 spheroids. Although cells in the inner region had mostly G1-phase DNA contents, 15-20% had S- and G2-phase DNA contents. Analysis of these cells using BrdU labeling and flow cytometric analysis with a monoclonal antibody to BrdU indicated that the inner region cells were not synthesizing DNA. Thus, the authors were able to measure the radiation response of cells arrested in G1, S and G2 cell cycle phases. Comparison of inner and outer spheroid regions, and monolayer cultures, indicates that it is improper to extrapolate age response data in standard culture conditions to the situation in spheroids

  17. Regularity of survival of the radiation cell progeny

    Bychkovskaya, I.B.

    1978-01-01

    Considered are lethal events, occurring in irradiated cell posterity. The mechanisms promoting increased dying off in irradiated cell posterity, are not clear. The mechanism of stable inherited increase of cellular mortality level is not connected with mutations absolutely

  18. Survival of the fittest?--survival of stored red blood cells after transfusion.

    Luten, M.; Roerdinkholder-Stoelwinder, B.; Bost, H.J.; Bosman, G.J.C.G.M.

    2004-01-01

    During the last 90 years many developments have taken place in the world of blood transfusion. Several anticoagulants and storage solutions have been developed. Also the blood processing has undergone many changes. At the moment, in The Netherlands, red blood cell (RBC) concentrates (prepared from a

  19. Metabolic stress responses in Drosophila are modulated by brain neurosecretory cells that produce multiple neuropeptides.

    Lily Kahsai

    Full Text Available In Drosophila, neurosecretory cells that release peptide hormones play a prominent role in the regulation of development, growth, metabolism, and reproduction. Several types of peptidergic neurosecretory cells have been identified in the brain of Drosophila with release sites in the corpora cardiaca and anterior aorta. We show here that in adult flies the products of three neuropeptide precursors are colocalized in five pairs of large protocerebral neurosecretory cells in two clusters (designated ipc-1 and ipc-2a: Drosophila tachykinin (DTK, short neuropeptide F (sNPF and ion transport peptide (ITP. These peptides were detected by immunocytochemistry in combination with GFP expression driven by the enhancer trap Gal4 lines c929 and Kurs-6, both of which are expressed in ipc-1 and 2a cells. This mix of colocalized peptides with seemingly unrelated functions is intriguing and prompted us to initiate analysis of the function of the ten neurosecretory cells. We investigated the role of peptide signaling from large ipc-1 and 2a cells in stress responses by monitoring the effect of starvation and desiccation in flies with levels of DTK or sNPF diminished by RNA interference. Using the Gal4-UAS system we targeted the peptide knockdown specifically to ipc-1 and 2a cells with the c929 and Kurs-6 drivers. Flies with reduced DTK or sNPF levels in these cells displayed decreased survival time at desiccation and starvation, as well as increased water loss at desiccation. Our data suggest that homeostasis during metabolic stress requires intact peptide signaling by ipc-1 and 2a neurosecretory cells.

  20. Reducing macrophages to improve bone marrow stromal cell survival in the contused spinal cord.

    Ritfeld, G.J.; Nandoe Tewarie, R.D.S.; Rahiem, S.T.; Hurtado, A.; Roos, R.A.; Grotenhuis, A.; Oudega, M.

    2010-01-01

    We tested whether reducing macrophage infiltration would improve the survival of allogeneic bone marrow stromal cells (BMSC) transplanted in the contused adult rat thoracic spinal cord. Treatment with cyclosporine, minocycline, or methylprednisolone all resulted in a significant decrease in

  1. Survival rate of eukaryotic cells following electrophoretic nanoinjection

    Simonis, Matthias; H?bner, Wolfgang; Wilking, Alice; Huser, Thomas; Hennig, Simon

    2017-01-01

    Insertion of foreign molecules such as functionalized fluorescent probes, antibodies, or plasmid DNA to living cells requires overcoming the plasma membrane barrier without harming the cell during the staining process. Many techniques such as electroporation, lipofection or microinjection have been developed to overcome the cellular plasma membrane, but they all result in reduced cell viability. A novel approach is the injection of cells with a nanopipette and using electrophoretic forces for...

  2. Commitment to glycolysis sustains survival of NO-producing inflammatory dendritic cells

    Everts, Bart; Amiel, Eyal; van der Windt, Gerritje J. W.; Freitas, Tori C.; Chott, Robert; Yarasheski, Kevin E.; Pearce, Erika L.; Pearce, Edward J.

    2012-01-01

    TLR agonists initiate a rapid activation program in dendritic cells (DCs) that requires support from metabolic and bioenergetic resources. We found previously that TLR signaling promotes aerobic glycolysis and a decline in oxidative phosphorylation (OXHPOS) and that glucose restriction prevents

  3. TOR, the Gateway to Cellular Metabolism, Cell Growth, and Disease.

    Blenis, John

    2017-09-21

    Michael N. Hall is this year's recipient of the Lasker Basic Medical Research Award for the identification of the target of rapamycin, TOR. TOR is a master regulator of the cell's growth and metabolic state, and its dysregulation contributes to a variety of diseases, including diabetes, obesity, neurodegenerative disorders, aging, and cancer, making the TOR pathway an attractive therapeutic target. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  4. The essential role of the Deinococcus radiodurans ssb gene in cell survival and radiation tolerance.

    J Scott Lockhart

    Full Text Available Recent evidence has implicated single-stranded DNA-binding protein (SSB expression level as an important factor in microbial radiation resistance. The genome of the extremely radiation resistant bacterium Deinococcus radiodurans contains genes for two SSB homologs: the homodimeric, canonical Ssb, encoded by the gene ssb, and a novel pentameric protein encoded by the gene ddrB. ddrB is highly induced upon exposure to radiation, and deletions result in decreased radiation-resistance, suggesting an integral role of the protein in the extreme resistance exhibited by this organism. Although expression of ssb is also induced after irradiation, Ssb is thought to be involved primarily in replication. In this study, we demonstrate that Ssb in D. radiodurans is essential for cell survival. The lethality of an ssb deletion cannot be complemented by providing ddrB in trans. In addition, the radiation-sensitive phenotype conferred by a ddrB deletion is not alleviated by providing ssb in trans. By altering expression of the ssb gene, we also show that lower levels of transcription are required for optimal growth than are necessary for high radiation resistance. When expression is reduced to that of E. coli, ionizing radiation resistance is similarly reduced. UV resistance is also decreased under low ssb transcript levels where growth is unimpaired. These results indicate that the expression of ssb is a key component of both normal cellular metabolism as well as pathways responsible for the high radiation tolerance of D. radiodurans.

  5. Cyclooxygenase-2: A Role in Cancer Stem Cell Survival and Repopulation of Cancer Cells during Therapy

    Lisa Y. Pang

    2016-01-01

    Full Text Available Cyclooxygenase-2 (COX-2 is an inducible form of the enzyme that catalyses the synthesis of prostanoids, including prostaglandin E2 (PGE2, a major mediator of inflammation and angiogenesis. COX-2 is overexpressed in cancer cells and is associated with progressive tumour growth, as well as resistance of cancer cells to conventional chemotherapy and radiotherapy. These therapies are often delivered in multiple doses, which are spaced out to allow the recovery of normal tissues between treatments. However, surviving cancer cells also proliferate during treatment intervals, leading to repopulation of the tumour and limiting the effectiveness of the treatment. Tumour cell repopulation is a major cause of treatment failure. The central dogma is that conventional chemotherapy and radiotherapy selects resistant cancer cells that are able to reinitiate tumour growth. However, there is compelling evidence of an active proliferative response, driven by increased COX-2 expression and downstream PGE2 release, which contribute to the repopulation of tumours and poor patient outcome. In this review, we will examine the evidence for a role of COX-2 in cancer stem cell biology and as a mediator of tumour repopulation that can be molecularly targeted to overcome resistance to therapy.

  6. Polyphosphate is a key factor for cell survival after DNA damage in eukaryotic cells.

    Bru, Samuel; Samper-Martín, Bàrbara; Quandt, Eva; Hernández-Ortega, Sara; Martínez-Laínez, Joan M; Garí, Eloi; Rafel, Marta; Torres-Torronteras, Javier; Martí, Ramón; Ribeiro, Mariana P C; Jiménez, Javier; Clotet, Josep

    2017-09-01

    Cells require extra amounts of dNTPs to repair DNA after damage. Polyphosphate (polyP) is an evolutionary conserved linear polymer of up to several hundred inorganic phosphate (Pi) residues that is involved in many functions, including Pi storage. In the present article, we report on findings demonstrating that polyP functions as a source of Pi when required to sustain the dNTP increment essential for DNA repair after damage. We show that mutant yeast cells without polyP produce less dNTPs upon DNA damage and that their survival is compromised. In contrast, when polyP levels are ectopically increased, yeast cells become more resistant to DNA damage. More importantly, we show that when polyP is reduced in HEK293 mammalian cell line cells and in human dermal primary fibroblasts (HDFa), these cells become more sensitive to DNA damage, suggesting that the protective role of polyP against DNA damage is evolutionary conserved. In conclusion, we present polyP as a molecule involved in resistance to DNA damage and suggest that polyP may be a putative target for new approaches in cancer treatment or prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Comprehensive Mapping of Pluripotent Stem Cell Metabolism Using Dynamic Genome-Scale Network Modeling

    Sriram Chandrasekaran

    2017-12-01

    Full Text Available Summary: Metabolism is an emerging stem cell hallmark tied to cell fate, pluripotency, and self-renewal, yet systems-level understanding of stem cell metabolism has been limited by the lack of genome-scale network models. Here, we develop a systems approach to integrate time-course metabolomics data with a computational model of metabolism to analyze the metabolic state of naive and primed murine pluripotent stem cells. Using this approach, we find that one-carbon metabolism involving phosphoglycerate dehydrogenase, folate synthesis, and nucleotide synthesis is a key pathway that differs between the two states, resulting in differential sensitivity to anti-folates. The model also predicts that the pluripotency factor Lin28 regulates this one-carbon metabolic pathway, which we validate using metabolomics data from Lin28-deficient cells. Moreover, we identify and validate metabolic reactions related to S-adenosyl-methionine production that can differentially impact histone methylation in naive and primed cells. Our network-based approach provides a framework for characterizing metabolic changes influencing pluripotency and cell fate. : Chandrasekaran et al. use computational modeling, metabolomics, and metabolic inhibitors to discover metabolic differences between various pluripotent stem cell states and infer their impact on stem cell fate decisions. Keywords: systems biology, stem cell biology, metabolism, genome-scale modeling, pluripotency, histone methylation, naive (ground state, primed state, cell fate, metabolic network

  8. Mammal survival at the Cretaceous–Palaeogene boundary: metabolic homeostasis in prolonged tropical hibernation in tenrecs

    Lovegrove, Barry G.; Lobban, Kerileigh D.; Levesque, Danielle L.

    2014-01-01

    Free-ranging common tenrecs, Tenrec ecaudatus, from sub-tropical Madagascar, displayed long-term (nine months) hibernation which lacked any evidence of periodic interbout arousals (IBAs). IBAs are the dominant feature of the mammalian hibernation phenotype and are thought to periodically restore long-term ischaemia damage and/or metabolic imbalances (depletions and accumulations). However, the lack of IBAs in tenrecs suggests no such pathology at hibernation Tbs > 22°C. The long period of tro...

  9. Flow cytometric determination of radiation-induced chromosome damage and its correlation with cell survival

    Welleweerd, J.; Wilder, M.E.; Carpenter, S.G.; Raju, M.R.

    1984-01-01

    Chinese hamster M3-1 cells were irradiated with several doses of x rays or α particles from 238 Pu. Propidium iodide-stained chromosome suspensions were prepared at different times after irradiation; cells were also assayed for survival. The DNA histograms of these chromosomes showed increased background counts with increased doses of radiation. This increase in background was cell-cycle dependent and was correlated with cell survival. The correlation between radiation-induced chromosome damage and cell survival was the same for X rays and α particles. Data are presented which indicate that flow cytometric analysis of chromosomes of irradiated cell populations can be a useful adjunct to classical cytogenic analysis of irradiation-induced chromosomal damage by virtue of its ability to express and measure chromosomal damage not seen by classical cytogenic methods

  10. Mathematical simulation of influence of irradiated cell reparative system saturation on cell survival. Communication 1. Simulation of survival curves in prokaryotes

    Knyigavko, V.G.; Meshcheryakova, O.P.; Radzyishevs'ka, Je.B.

    2004-01-01

    Mathematical models of the processes of forming survival curves for prokaryotes which are based on the idea about the possibility of saturation of radiation lesion reparation systems of DNA of the irradiated cells at the dose increase were worked out. For the simplest of the discussed models the authors discuss the question about the methods of evaluation of the model parameters

  11. Relation of intracellular cyclic AMP to the shape of mammalian cell survival curves

    Lehnert, S.

    1975-01-01

    Results of experiments with V79 cells growing in tissue culture indicate that the reproductive survival of cells following irradiation is influenced by the level of intracellular 3', 5'-cyclic adenosine monophosphate (cyclic AMP) at the time of irradiation. Cells containing high levels of cyclic AMP induced by treatments with drugs show a characteristic survival curve in which the extent of the shoulder is increased so that the survival after low doses is enhanced. The exponential slope or D 0 , however, is decreased so that at high doses the survival of cells containing high levels of cyclic AMP may be less than that of controls. Naturally occurring changes in radiosensitivity such as those observed as cells pass through the division cycle, may also be related to parallel changes in cyclic AMP concentration occurring during the cycle. Injection of mice with compounds producing elevated cyclic AMP prior to whole-body irradiation increases survival at seven days post-irradiation. The shape of the survival curve for intestinal stem cells in these mice differs from that of the control in having an increased extrapolation number; no change in D 0 is observed in this in vivo situation. (author)

  12. Collagen Promotes Higher Adhesion, Survival and Proliferation of Mesenchymal Stem Cells.

    Chinnapaka Somaiah

    Full Text Available Mesenchymal stem cells (MSC can differentiate into several cell types and are desirable candidates for cell therapy and tissue engineering. However, due to poor cell survival, proliferation and differentiation in the patient, the therapy outcomes have not been satisfactory. Although several studies have been done to understand the conditions that promote proliferation, differentiation and migration of MSC in vitro and in vivo, still there is no clear understanding on the effect of non-cellular bio molecules. Of the many factors that influence the cell behavior, the immediate cell microenvironment plays a major role. In this context, we studied the effect of extracellular matrix (ECM proteins in controlling cell survival, proliferation, migration and directed MSC differentiation. We found that collagen promoted cell proliferation, cell survival under stress and promoted high cell adhesion to the cell culture surface. Increased osteogenic differentiation accompanied by high active RHOA (Ras homology gene family member A levels was exhibited by MSC cultured on collagen. In conclusion, our study shows that collagen will be a suitable matrix for large scale production of MSC with high survival rate and to obtain high osteogenic differentiation for therapy.

  13. Progression-free survival, post-progression survival, and tumor response as surrogate markers for overall survival in patients with extensive small cell lung cancer

    Hisao Imai

    2015-01-01

    Full Text Available Objectives: The effects of first-line chemotherapy on overall survival (OS might be confounded by subsequent therapies in patients with small cell lung cancer (SCLC. We examined whether progression-free survival (PFS, post-progression survival (PPS, and tumor response could be valid surrogate endpoints for OS after first-line chemotherapies for patients with extensive SCLC using individual-level data. Methods: Between September 2002 and November 2012, we analyzed 49 cases of patients with extensive SCLC who were treated with cisplatin and irinotecan as first-line chemotherapy. The relationships of PFS, PPS, and tumor response with OS were analyzed at the individual level. Results: Spearman rank correlation analysis and linear regression analysis showed that PPS was strongly correlated with OS (r = 0.97, p < 0.05, R 2 = 0.94, PFS was moderately correlated with OS (r = 0.58, p < 0.05, R 2 = 0.24, and tumor shrinkage was weakly correlated with OS (r = 0.37, p < 0.05, R 2 = 0.13. The best response to second-line treatment, and the number of regimens employed after progression beyond first-line chemotherapy were both significantly associated with PPS ( p ≤ 0.05. Conclusion: PPS is a potential surrogate for OS in patients with extensive SCLC. Our findings also suggest that subsequent treatment after disease progression following first-line chemotherapy may greatly influence OS.

  14. Subversion of Schwann Cell Glucose Metabolism by Mycobacterium leprae*

    Medeiros, Rychelle Clayde Affonso; Girardi, Karina do Carmo de Vasconcelos; Cardoso, Fernanda Karlla Luz; Mietto, Bruno de Siqueira; Pinto, Thiago Gomes de Toledo; Gomez, Lilian Sales; Rodrigues, Luciana Silva; Gandini, Mariana; Amaral, Julio Jablonski; Antunes, Sérgio Luiz Gomes; Corte-Real, Suzana; Rosa, Patricia Sammarco; Pessolani, Maria Cristina Vidal; Nery, José Augusto da Costa; Sarno, Euzenir Nunes; Batista-Silva, Leonardo Ribeiro; Sola-Penna, Mauro; Oliveira, Marcus Fernandes; Moraes, Milton Ozório; Lara, Flavio Alves

    2016-01-01

    Mycobacterium leprae, the intracellular etiological agent of leprosy, infects Schwann promoting irreversible physical disabilities and deformities. These cells are responsible for myelination and maintenance of axonal energy metabolism through export of metabolites, such as lactate and pyruvate. In the present work, we observed that infected Schwann cells increase glucose uptake with a concomitant increase in glucose-6-phosphate dehydrogenase (G6PDH) activity, the key enzyme of the oxidative pentose pathway. We also observed a mitochondria shutdown in infected cells and mitochondrial swelling in pure neural leprosy nerves. The classic Warburg effect described in macrophages infected by Mycobacterium avium was not observed in our model, which presented a drastic reduction in lactate generation and release by infected Schwann cells. This effect was followed by a decrease in lactate dehydrogenase isoform M (LDH-M) activity and an increase in cellular protection against hydrogen peroxide insult in a pentose phosphate pathway and GSH-dependent manner. M. leprae infection success was also dependent of the glutathione antioxidant system and its main reducing power source, the pentose pathway, as demonstrated by a 50 and 70% drop in intracellular viability after treatment with the GSH synthesis inhibitor buthionine sulfoximine, and aminonicotinamide (6-ANAM), an inhibitor of G6PDH 6-ANAM, respectively. We concluded that M. leprae could modulate host cell glucose metabolism to increase the cellular reducing power generation, facilitating glutathione regeneration and consequently free-radical control. The impact of this regulation in leprosy neuropathy is discussed. PMID:27555322

  15. Relationship between DNA repair and cell recovery: Importance of competing biochemical and metabolic processes

    Van Ankeren, S.C.; Wheeler, K.T.; Kansas Univ., Lawrence

    1985-01-01

    The relationship between the inhibition of repair of radiation-induced DNA damage and the inhibition of recovery from radiation-induced potentially lethal damage (PLD) by hypertonic treatment was compared in 9L/Ro rat brain tumor cells. Fed plateau phase cultures were γ-irradiated with 1500 rad and then immediately treated for 20 min with a 37 0 C isotonic (0.15 M) or hypertonic (0.50 M) salt solution. The kinetics of repair of radiation-induced DNA damage as assayed using alkaline filter elution were compared to those of recovery from radiation-induced PLD as assayed by colony formation. hypertonic treatment of unirradiated cells produced neither DNA damage nor cell kill. Post-irradiation hypertonic treatment inhibited both DNA repair and PLD recovery, while post-irradiation istonic treatment inhibited neither phenomenon. However, by 2 h after irradiation, the amount of DNA damage remaining after a 20 min hypertonic treatment was equivalent to that remaining after a 20 min isotonic treatment. In contrast, cell survival after hypertonic treatment remained 2 logs lower than after isotonic treatment even at times up to 24 h. These results suggest that the repair of radiation-induced DNA damage per per se is not causally related to recovery from radiation-induced PLD. However, the data are consistent with the time of DNA repair as an important parameter in determining cell survival and, therefore, tend to support the hypothesis that imbalances in sets of competing biochemical or metabolic processes determine survival rather than the presence of a single class of unrepaired DNA lesions. (orig.)

  16. Effect of oxygen on formation of micronuclei and binucleated cells and cell survival in γ-irradiated 3T3 cells

    Zhang Peng; Zheng Xiulong

    1991-01-01

    Formation of micronuclei and binucleate cells and their relationships with cell survival were studied in the aerobically- and anaerobically-irradiated 3T3 cells. The results showed taht frequency of micronuclei, percentage of micronucleus cells and percentage of binucleate cells increased linearly with the radiation dose in certain range. Oxygen enhancement ratios (OER) of micronucleus frequency, percentage of micronucleus cells, percentage of binucleate cells and cell survival were 2.02, 1.96, 1.87 and 1.83 respectively. The percentage of micronucleus cells or the percentage of micronucleus cells plus binucleate cells correlated negatively well with cell survival. The mechanism of oxygen effect in the radiation response of 3T3 cells and the significance of formation of micronuclei and binucleate cells were discussed

  17. Ensemble of cell survival experiments after ion irradiation for validation of RBE models

    Friedrich, Thomas; Scholz, Uwe; Scholz, Michael [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Durante, Marco [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Institut fuer Festkoerperphysik, TU Darmstadt, Darmstadt (Germany)

    2012-07-01

    There is persistent interest in understanding the systematics of the relative biological effectiveness (RBE). Models such as the Local Effect Model (LEM) or the Microdosimetric Kinetic Model have the goal to predict the RBE. For the validation of these models a collection of many in-vitro cell survival experiments is most appropriate. The set-up of an ensemble of in-vitro cell survival data comprising about 850 survival experiments after both ion and photon irradiation is reported. The survival curves have been taken out from publications. The experiments encompass survival curves obtained in different labs, using different ion species from protons to uranium, varying irradiation modalities (shaped or monoenergetic beam), various energies and linear energy transfers, and a whole variety of cell types (human or rodent; normal, mutagenic or tumor; radioresistant or -sensitive). Each cell survival curve has been parameterized by the linear-quadratic model. The photon parameters have been added to the data base to allow to calculate the experimental RBE to any survival level. We report on experimental trends found within the data ensemble. The data will serve as a testing ground for RBE models such as the LEM. Finally, a roadmap for further validation and first model results using the data base in combination with the LEM are presented.

  18. Collective Sensing of β-Cells Generates the Metabolic Code

    Dean Korošak

    2018-01-01

    Full Text Available Major part of a pancreatic islet is composed of β-cells that secrete insulin, a key hormone regulating influx of nutrients into all cells in a vertebrate organism to support nutrition, housekeeping or energy storage. β-cells constantly communicate with each other using both direct, short-range interactions through gap junctions, and paracrine long-range signaling. However, how these cell interactions shape collective sensing and cell behavior in islets that leads to insulin release is unknown. When stimulated by specific ligands, primarily glucose, β-cells collectively respond with expression of a series of transient Ca2+ changes on several temporal scales. Here we reanalyze a set of Ca2+ spike trains recorded in acute rodent pancreatic tissue slice under physiological conditions. We found strongly correlated states of co-spiking cells coexisting with mostly weak pairwise correlations widespread across the islet. Furthermore, the collective Ca2+ spiking activity in islet shows on-off intermittency with scaling of spiking amplitudes, and stimulus dependent autoassociative memory features. We use a simple spin glass-like model for the functional network of a β-cell collective to describe these findings and argue that Ca2+ spike trains produced by collective sensing of β-cells constitute part of the islet metabolic code that regulates insulin release and limits the islet size.

  19. Metabolism plays the key roles in Th cells differentiation

    A. Hosseinzadeh

    2016-12-01

    Full Text Available The increasing rate of autoimmunity in recent decades cannot be related to only genetic instabilities and disorders. Diet can directly influence our health. Studies have shown that there is a relationship between nutritional elements and alteration in the immune system. Among immune cells, the function of T lymphocyte is important in directing immune response. T CD4+ cells lead other immune cells to respond to pathogens by secreting cytokines. HIV+ patients, who have largely lost their T CD4+ cells, are susceptible to opportunistic infections, which do not normally affect healthy people. It seems that the metabolism of T cells is critical for their differentiation and their consequent functions. After activation, T cells need to undergo clonal expansion, which is a high energy- consuming process. Studies have shown that specific metabolites deprivation or their excess supply affects T CD4+cells subsets differentiation. Abnormal induction of subsets of T CD4+ cells causes some autoimmunity reactions and hyper-sensitivity as well, which may result from imbalance of diet uptake. In this mini-review, we describe the findings about fatty acids, glucose, amino acids, and vitamins, which are effective in determining the fates of T CD4+ cells. These findings may help us uncover the role of diet in autoimmune diseases.

  20. Metabolic characterization of invaded cells of the pancreatic cancer cell line, PANC?1

    Fujita, Mayumi; Imadome, Kaori; Imai, Takashi

    2017-01-01

    We previously reported that about 0.4% of cells in the cultured human pancreatic cancer cell line, PANC?1, can invade matrigel during the transwell invasion assay, suggesting that these invaded PANC?1 cells may have specific characteristics to keep their invasive potential. To identify the metabolic characterization specific in the invaded PANC?1 cells, metabolome analysis of the invaded PANC?1 compared with the whole cultured PANC?1 was performed using CE?TOFMS, and concentrations of 110 met...

  1. Foxp3 overexpression in tumor cells predicts poor survival in oral squamous cell carcinoma

    Song, Jing-Jing; Zhao, Si-Jia; Fang, Juan; Ma, Da; Liu, Xiang-Qi; Chen, Xiao-Bing; Wang, Yun; Cheng, Bin; Wang, Zhi

    2016-01-01

    Forkhead Box P3 (Foxp3) is a regulatory T cells marker, and its expression correlates with prognosis in a number of malignancies. The aim of this study is to determine the relationship of Foxp3 expression with clinicopathological parameters and prognosis in oral squamous cell carcinoma (OSCC). Foxp3 expression was examined using immunohistochemistry (IHC) in paraffin-embedded tissue samples from 273 OSCC patients. Statistical analysis was performed to evaluate the associations between Foxp3 expression, the clinicopathologic characteristics and prognostic factors in OSCC. Foxp3 protein expression was significantly associated with lymph node metastasis (P <0.01). Both univariate and multivariate analyses revealed that Foxp3 was an independent factor for both 5 years overall survival (OS) and relapse-free survival (RFS) (both P <0.01). Patients with Foxp3 overexpression had shorter OS and RFS. Our results determined that elevated Foxp3 protein expression was a predictive factor of outcome in OSCC and could act as a promising therapeutic target

  2. Diet and cognition: interplay between cell metabolism and neuronal plasticity.

    Gomez-Pinilla, Fernando; Tyagi, Ethika

    2013-11-01

    To discuss studies in humans and animals revealing the ability of foods to benefit the brain: new information with regards to mechanisms of action and the treatment of neurological and psychiatric disorders. Dietary factors exert their effects on the brain by affecting molecular events related to the management of energy metabolism and synaptic plasticity. Energy metabolism influences neuronal function, neuronal signaling, and synaptic plasticity, ultimately affecting mental health. Epigenetic regulation of neuronal plasticity appears as an important mechanism by which foods can prolong their effects on long-term neuronal plasticity. The prime focus of the discussion is to emphasize the role of cell metabolism as a mediator for the action of foods on the brain. Oxidative stress promotes damage to phospholipids present in the plasma membrane such as the omega-3 fatty acid docosahexenoic acid, disrupting neuronal signaling. Thus, dietary docosahexenoic acid seems crucial for supporting plasma membrane function, interneuronal signaling, and cognition. The dual action of brain-derived neurotrophic factor in neuronal metabolism and synaptic plasticity is crucial for activating signaling cascades under the action of diet and other environmental factors, using mechanisms of epigenetic regulation.

  3. Impact of CD133 positive stem cell proportion on survival in patients with glioblastoma multiforme

    Kase, Marju; Minajeva, Ave; Niinepuu, Kristi; Kase, Sandra; Vardja, Markus; Asser, Toomas; Jaal, Jana

    2013-01-01

    The aim of the study was to assess the impact of CD133-positive (CD133+) cancer stem cell proportions on treatment results of glioblastoma multiforme (GBM) patients. Patients with GBM (n = 42) received postoperative radiotherapy (± chemotherapy). Surgically excised GBM tissue sections were immunohistochemically examined for CD133 expression. The proportions of CD133+ GBM cells were determined (%). The proportion of CD133+ GBM stem cells was established by 2 independent researchers whose results were in good accordance (R = 0.8, p < 0.01). Additionally, CD133 expression levels were correlated with patients overall survival. The proportion of CD133+ cells varied between patients, being from 0.5% to 82%. Mean and median proportions of CD133+ cells of the entire study group were 33% ± 24% (mean ± SD) and 28%, respectively. Clinical data do not support the association between higher proportion of stem cells and the aggressiveness of GBM. Median survival time of the study group was 10.0 months (95% CI 9.0–11.0). The survival time clearly depended on the proportion of CD133+ cells (log rank test, p = 0.02). Median survival times for patients with low (< median) and high (≥ median) proportion of CD133+ cells were 9.0 months (95% CI 7.6–10.5) and 12.0 months (95% CI 9.3–14.7), respectively. In multivariate analysis, the proportion of CD133+ cells emerged as a significant independent predictor for longer overall survival (HR 2.0, 95% CI 1.0–3.8, p = 0.04). In patients with higher stem cell proportion, significantly longer survival times after postoperative radiotherapy were achieved. Underlying reasons and possible higher sensitivity of GBM stem cells to fractionated radio-therapy should be clarified in further studies

  4. Does the band cell survive the 21st century?

    Meer, W. van der; Gelder, W. van; Keijzer, R. de; Willems, H.

    2006-01-01

    OBJECTIVES: The differentiation of white blood cells is a worldwide-accepted method to obtain medical information. The conventional microscopic differential, however, is a laborious and expensive test with a low statistical value. Especially for band cell identification there is a wide range of

  5. Mitochondrial peroxiredoxin 3 regulates sensory cell survival in the cochlea.

    Fu-Quan Chen

    Full Text Available This study delineates the role of peroxiredoxin 3 (Prx3 in hair cell death induced by several etiologies of acquired hearing loss (noise trauma, aminoglycoside treatment, age. In vivo, Prx3 transiently increased in mouse cochlear hair cells after traumatic noise exposure, kanamycin treatment, or with progressing age before any cell loss occurred; when Prx3 declined, hair cell loss began. Maintenance of high Prx3 levels via treatment with the radical scavenger 2,3-dihydroxybenzoate prevented kanamycin-induced hair cell death. Conversely, reducing Prx3 levels with Prx3 siRNA increased the severity of noise-induced trauma. In mouse organ of Corti explants, reactive oxygen species and levels of Prx3 mRNA and protein increased concomitantly at early times of drug challenge. When Prx3 levels declined after prolonged treatment, hair cells began to die. The radical scavenger p-phenylenediamine maintained Prx3 levels and attenuated gentamicin-induced hair cell death. Our results suggest that Prx3 is up-regulated in response to oxidative stress and that maintenance of Prx3 levels in hair cells is a critical factor in their susceptibility to acquired hearing loss.

  6. Estrogen-induced disruption of intracellular iron metabolism leads to oxidative stress, membrane damage, and cell cycle arrest in MCF-7 cells.

    Bajbouj, Khuloud; Shafarin, Jasmin; Abdalla, Maher Y; Ahmad, Iman M; Hamad, Mawieh

    2017-10-01

    It is well established that several forms of cancer associate with significant iron overload. Recent studies have suggested that estrogen (E2) disrupts intracellular iron homeostasis by reducing hepcidin synthesis and maintaining ferroportin integrity. Here, the ability of E2 to alter intracellular iron status and cell growth potential was investigated in MCF-7 cells treated with increasing concentrations of E2. Treated cells were assessed for intracellular iron status, the expression of key proteins involved in iron metabolism, oxidative stress, cell survival, growth, and apoptosis. E2 treatment resulted in a significant reduction in hepcidin expression and a significant increase in hypoxia-inducible factor 1 alpha, ferroportin, transferrin receptor, and ferritin expression; a transient decrease in labile iron pool; and a significant increase in total intracellular iron content mainly at 20 nM/48 h E2 dose. Treated cells also showed increased total glutathione and oxidized glutathione levels, increased superoxide dismutase activity, and increased hemoxygenase 1 expression. Treatment with E2 at 20 nM for 48 h resulted in a significant reduction in cell growth (0.35/1 migration rate) and decreased cell survival (iron metabolism and precipitates adverse effects concerning cell viability, membrane integrity, and growth potential.

  7. Acceleration of astrocytic differentiation in neural stem cells surviving X-irradiation.

    Ozeki, Ayumi; Suzuki, Keiji; Suzuki, Masatoshi; Ozawa, Hiroki; Yamashita, Shunichi

    2012-03-28

    Neural stem cells (NSCs) are highly susceptible to DNA double-strand breaks; however, little is known about the effects of radiation in cells surviving radiation. Although the nestin-positive NSCs predominantly became glial fibrillary acidic protein (GFAP)-positive in differentiation-permissive medium, little or no cells were GFAP positive in proliferation-permissive medium. We found that more than half of the cells surviving X-rays became GFAP positive in proliferation-permissive medium. Moreover, localized irradiation stimulated differentiation of cells outside the irradiated area. These results indicate for the first time that ionizing radiation is able to stimulate astrocyte-specific differentiation of surviving NSCs, whose process is mediated both by the direct activation of nuclear factor-κB and by the indirect bystander effect induced by X-irradiation.

  8. Autologous cytokine-induced killer cell immunotherapy may improve overall survival in advanced malignant melanoma patients.

    Zhang, Yong; Zhu, Yu'nan; Zhao, Erjiang; He, Xiaolei; Zhao, Lingdi; Wang, Zibing; Fu, Xiaomin; Qi, Yalong; Ma, Baozhen; Song, Yongping; Gao, Quanli

    2017-11-01

    Our study was conducted to explore the efficacy of autologous cytokine-induced killer (CIK) cells in patients with advanced malignant melanoma. Materials & Methods: Here we reviewed 113 stage IV malignant melanoma patients among which 68 patients received CIK cell immunotherapy alone, while 45 patients accepted CIK cell therapy combined with chemotherapy. Results: We found that the median survival time in CIK cell group was longer than the combined therapy group (21 vs 15 months, p = 0.07). In addition, serum hemoglobin level as well as monocyte proportion and lymphocyte count were associated with patients' survival time. These indicated that CIK cell immunotherapy might extend survival time in advanced malignant melanoma patients. Furthermore, serum hemoglobin level, monocyte proportion and lymphocyte count could be prognostic indicators for melanoma.

  9. Estimation of transfused red cell survival using an enzyme-linked antiglobulin test

    Kickler, T.S.; Smith, B.; Bell, W.; Drew, H.; Baldwin, M.; Ness, P.M.

    1985-01-01

    An enzyme-linked antiglobulin test (ELAT) method was developed to estimate survival of transfused red cells. This procedure is based on a principle analogous to that of the Ashby technique were antigenically distinct red cells are transfused and their survival studied. The authors compared the ELAT survival to the 51 Chromium method ( 51 Cr) in four patients. Three patients with hypoproliferative anemias showed T 1/2 by ELAT of 17.5, 18, and 17 days versus 18.5, 20, and 19 days by the 51 Cr method. A fourth patient with traumatic cardiac hemolysis had two studies performed. In this case, the ELAT showed a T 1/2 of 10 and 8.1 days while 51 Cr T 1/2 values were 11 and 10.5 days. The ELAT method for measuring red cell survival yielded data which agreed closely with the results of the 51 Cr method. Although 51 Cr is the accepted method for red cell survival, the ELAT method can be used to estimate transfused red cell survival

  10. In vivo studies of the long-term 51Cr red cell survival of serologically incompatible red cell units

    Baldwin, M.L.; Ness, P.M.; Barrasso, C.; Kickler, T.S.; Drew, H.; Tsan, M.F.; Shirey, R.S.

    1985-01-01

    The long-term survival of serologically incompatible red cell units was measured in five patients with antibodies to high-frequency antigens. Initially, the survival of 1 ml of 51 Cr-labeled incompatible red cells was measured over 1 hour. After demonstrating that the 1-hour survival times were successful (greater than 70%), each patient then received 5 ml of the same 51 Cr-labeled red cells followed by the transfusion of the remainder of the red cell unit. The long-term T 1/2Cr survival for each case was patient 1 (anti-McCa), 15 days; patient 2 (anti-JMH), 12 days; patient 3 (anti-Kna), 31 days; patient 4 (anti-McCa), 12 days; and patient 5 (anti-Hya), 14 days. Each antibody tested in an in vitro homologous macrophage assay showed less than 5 percent phagocytosis. Anti-JMH was the only antibody to react with IgG subclass antisera and was determined to be IgG4. The macrophage assay, IgG subclass testing, and short-term (1 hour, 1 ml) 51 Cr survival studies all indicated that the short-term survival was good. However, only the measurement of long-term survival with transfused units of serologically incompatible red cells was able to determine the actual survival, and clinical significance of the alloantibodies. Determining the actual long-term survival by the method described here can be of importance for patients requiring chronic red cell transfusion

  11. An unexpected caffeine-enhanced survival in x-ray-sensitive variant cells

    Utsumi, Hiroshi

    1985-01-01

    The sensitivity of normal Chinese hamster cell lines, V79 and CHO, mouse cell lines, L5178Y and L, and human HeLa cells to the killing effect of x-ray is enhanced with addition of caffeine following x-ray irradiation in a dose-dependent fashion. However, the survival rate of variant cell (V79-AL162/S-10) increased with addition of low concentration of caffeine (caffeine-enhanced survival phenomenon). Therefore, the effects of protein synthesis-inhibiting agents, such as cycloheximide and puromycin, on caffeine-enhanced survival phenomenon were examined. This phenomenon was completely abolished by the inhibitory agents, but not abolished by DNA synthesis-damaging agents, such as excess thymidine and aphidicolin. DNA-damaging physiochemical factors, such as neutrons, U.V., methyl methanesulfonate and mitomycin C, were examined in relation to variant cells' sensitivity and caffeine-enhanced survival phenomenon. V79-AL162/S-10 cells showed high sensitivity to the killing effect of mitomycin C, but their survival rate returned to the rate of normal V79-B310H cells with addition of caffeine. (Namekawa, K.)

  12. IL-17-producing NKT cells depend exclusively on IL-7 for homeostasis and survival.

    Webster, K E; Kim, H-O; Kyparissoudis, K; Corpuz, T M; Pinget, G V; Uldrich, A P; Brink, R; Belz, G T; Cho, J-H; Godfrey, D I; Sprent, J

    2014-09-01

    Natural killer T (NKT) cells are innate-like T cells that rapidly recognize pathogens and produce cytokines that shape the ensuing immune response. IL-17-producing NKT cells are enriched in barrier tissues, such as the lung, skin, and peripheral lymph nodes, and the factors that maintain this population in the periphery have not been elucidated. Here we show that NKT17 cells deviate from other NKT cells in their survival requirements. In contrast to conventional NKT cells that are maintained by IL-15, RORγt(+) NKT cells are IL-15 independent and instead rely completely on IL-7. IL-7 initiates a T-cell receptor-independent (TCR-independent) expansion of NKT17 cells, thus supporting their homeostasis. Without IL-7, survival is dramatically impaired, yet residual cells remain lineage committed with no downregulation of RORγt evident. Their preferential response to IL-7 does not reflect enhanced signaling through STAT proteins, but instead is modulated via the PI3K/AKT/mTOR signaling pathway. The ability to compete for IL-7 is dependent on high-density IL-7 receptor expression, which would promote uptake of low levels of IL-7 produced in the non-lymphoid sites of lung and skin. This dependence on IL-7 is also reported for RORγt(+) innate lymphoid cells and CD4(+) Th17 cells, and suggests common survival requirements for functionally similar cells.

  13. EDAG promotes the expansion and survival of human CD34+ cells.

    Ke Zhao

    Full Text Available EDAG is multifunctional transcriptional regulator primarily expressed in the linloc-kit+Sca-1+ hematopoietic stem cells (HSC and CD34+ progenitor cells. Previous studies indicate that EDAG is required for maintaining hematopoietic lineage commitment balance. Here using ex vivo culture and HSC transplantation models, we report that EDAG enhances the proliferative potential of human cord blood CD34+ cells, increases survival, prevents cell apoptosis and promotes their repopulating capacity. Moreover, EDAG overexpression induces rapid entry of CD34+ cells into the cell cycle. Gene expression profile analysis indicate that EDAG knockdown leads to down-regulation of various positive cell cycle regulators including cyclin A, B, D, and E. Together these data provides novel insights into EDAG in regulation of expansion and survival of human hematopoietic stem/progenitor cells.

  14. Prognostic value of PET/CT in lung cancer. Study of survival and tumor metabolic characterization

    Ladron de Guevara, David; Fuentes Anibal; Farina, Ciro; Corral, Camilo; Pefaur, Raul

    2013-01-01

    PET/CT (Positron emission tomography/computed tomography) is a hybrid image modality widely used in oncology, for staging, therapy evaluation or follow up. Aim: To evaluate the prognostic value of PET/CT in lung cancer. Material and Methods: Retrospective review of PET/CT records, selecting 51 patients with a lung malignancy, mass or nodule referred for PET/CT between December 2008 and December 2010. All had pathological confirmation of malignancy and had not been treated previously. Age, gender, body mass index, radiological features of lung tumor and metastases, and lung tumor 18 F-fluoro-2-deoxy-d-glucose uptake using the SUV (Standardized uptake value) index were recorded. Survival was analyzed using Kaplan-Meier curves and a Cox proportional regression analysis. Results: Pathology confirmed the presence of lung cancer in 47 patients aged 30 to 88 years. Four patients (7.8%) had other type of tumors such as carcinoid or lymphoma. Fifty percent of lung cancer patients died during a mean observation lapse of 18 months (range: 2-34 months). Patients with metastases, local lymph node involvement, a lung tumor size ≥ 3 cm and high tumor uptake (SUVmax > 6) had significantly lower survival. Occurrence of metastases was the only independent prognostic factor in the Cox regression. A lung lesion with a SUVmax ≥ 12 was always associated to hilar/mediastinal lymph node involvement. Conclusions: PET/CT imaging gives important prognostic information in lung cancer patients

  15. Metabolism of 4-nitrobiphenyl (NBP) by cultured rat urothelial cells

    Swaminathan, S.; Lang, D.B.; Reznikoff, C.A.

    1986-01-01

    The potential of rat urothelial cells to metabolize NBP was evaluated by incubating 4.3 x 10 7 viable cells with 20 μM [ 3 H]NBP in a serum free medium for 48 hours. The culture medium was examined for metabolites of NBP by extraction with ethyl acetate and subsequent chromatographic analysis. High pressure liquid chromatography of the solvent extract using a Whatman ODS-3, C-18 column in 70% methanol-water at a flow rate of 1 ml/min revealed two major peaks at retention times of approximately 8 and 13 min. Thin layer chromatography showed two regions of radioactivity at Rf values of 0.35 and 0.83, the latter corresponding with NBP. Based on the chromatographic data the metabolite with the retention time of 8.0 min in HPLC and an Rf of 0.35 in TLC has been tentatively identified as 4-acetylaminobiphenyl. Analysis of binding to proteins and nucleic acids following exposure to [ 3 H]NBP revealed a significant amount (0.03% of initially applied radioactivity) in the protein fractions. Control samples of NBP incubated in medium, without the urothelial cells revealed only the parent compound. These data suggest that rat bladder cells possess the metabolic capability to reduce NBP and to generate reactive metabolites that bind to cellular macromolecules

  16. Matrin 3 as a key regulator of endothelial cell survival

    Przygodzka, Patrycja; Boncela, Joanna; Cierniewski, Czeslaw S.

    2011-01-01

    Matrin 3 is an integral component of nuclear matrix architecture that has been implicated in interacting with other nuclear proteins and thus modulating the activity of proximal promoters. In this study, we evaluated the contribution of this protein to proliferation of endothelial cells. To selectively modulate matrin 3 expression, we used siRNA oligonucleotides and transfection of cells with a pEGFP-N1-Mtr3. Our data indicate that downregulation of matrin 3 is responsible for reduced proliferation and leads to necrosis of endothelial cells. This conclusion is supported by observations that reducing matrin 3 expression results in (a) producing signs of necrosis detected by PI staining, LDH release, and scatter parameters in flow cytometry, (b) affecting cell cycle progression. It does not cause (c) membrane asymmetry of cells as indicated by lack of Annexin V binding as well as (d) activation of caspase 3 and cleavage of PARP. We conclude that matrin 3 plays a significant role in controlling cell growth and proliferation, probably via formation of complexes with nuclear proteins that modulate pro- and antiapoptotic signaling pathways. Thus, degradation of matrin 3 may be a switching event that induces a shift from apoptotic to necrotic death of cells.

  17. Apoptosis, energy metabolism, and fraction of radiobiologically hypoxic cells: a study of human melanoma multicellular spheroids.

    Rofstad, E K; Eide, K; Skøyum, R; Hystad, M E; Lyng, H

    1996-09-01

    The magnitude of the fraction of radiobiologically hypoxic cells in tumours is generally believed to reflect the efficiency of the vascular network. Theoretical studies have suggested that the hypoxic fraction might also be influenced by biological properties of the tumour cells. Quantitative experimental results of cell energy metabolism, hypoxia- induced apoptosis, and radiobiological hypoxia are reported here. Human melanoma multicellular spheroids (BEX-c and WIX-c) were used as tumour models to avoid confounding effects of the vascular network. Radiobiological studies showed that the fractions of hypoxic cells in 1000-microM spheroids were 32 +/- 12% (BEX-c) and 2.5 +/- 1.1% (WIX-c). The spheroid hypoxic volume fractions (28 +/- 6% (BEX-c) and 1.4 +/- 7% (WIX-c)), calculated from the rate of oxygen consumption per cell, the cell packing density, and the thickness of the viable rim, were similar to the fractions of radiobiologically hypoxic cells. Large differences between tumours in fraction of hypoxic cells are therefore not necessarily a result of differences in the efficiency of the vascular network. Studies of monolayer cell cultures, performed to identify the biological properties of the BEX-c and WIX-c cells leading to this large difference in fraction of hypoxic cells, gave the following results: (1) WIX-c showed lower cell surviving fractions after exposure to hypoxia than BEX-c, (2) WIX-c showed higher glucose uptake and lactate release rates than BEX-c both under aerobic and hypoxic conditions, and (3) hypoxia induced apoptosis in WIX-c but not in BEX-c. These observations suggested that the difference between BEX-c and WIX-c spheroids in fraction of hypoxic cells resulted partly from differences in cell energy metabolism and partly from a difference in capacity to retain viability under hypoxic stress. The induction of apoptosis by hypoxia was identified as a phenomenon which has an important influence on the magnitude of the fraction of

  18. Survival of Lymphatic Cells after X-Irradiation in Mice

    Vos, O. [Medical Biological Laboratory, National Defense Research Organization TNO, Ruswuk, Z.H. (Netherlands)

    1967-07-15

    Lymphatic tissues are generally classified among the most radiosensitive tissues of the body. The main reason for this is that histologically extensive destruction is found within a few hours after irradiation. We tried to estimate the degree of cellular degeneration by making cell suspensions from lymph nodes and thymus of mice at different times after X-irradiation with 800 R or at 24 h after radiation with different doses. The numbers of normal viable cells we obtained were expressed as percentages of the cells recovered from unirradiated control mice.

  19. The impact of metabolism on aging and cell size in single yeast cells

    Huberts, Daphne

    2015-01-01

    The aim of this thesis was to determine how metabolism affects yeast aging in single yeast cells using a novel microfluidic device. We first review how cells are able to sense nutrients in their environment and then describe the use of the microfluidic dissection platform that greatly improves our

  20. Cell wall-bound silicon optimizes ammonium uptake and metabolism in rice cells.

    Sheng, Huachun; Ma, Jie; Pu, Junbao; Wang, Lijun

    2018-05-16

    Turgor-driven plant cell growth depends on cell wall structure and mechanics. Strengthening of cell walls on the basis of an association and interaction with silicon (Si) could lead to improved nutrient uptake and optimized growth and metabolism in rice (Oryza sativa). However, the structural basis and physiological mechanisms of nutrient uptake and metabolism optimization under Si assistance remain obscure. Single-cell level biophysical measurements, including in situ non-invasive micro-testing (NMT) of NH4+ ion fluxes, atomic force microscopy (AFM) of cell walls, and electrolyte leakage and membrane potential, as well as whole-cell proteomics using isobaric tags for relative and absolute quantification (iTRAQ), were performed. The altered cell wall structure increases the uptake rate of the main nutrient NH4+ in Si-accumulating cells, whereas the rate is only half in Si-deprived counterparts. Rigid cell walls enhanced by a wall-bound form of Si as the structural basis stabilize cell membranes. This, in turn, optimizes nutrient uptake of the cells in the same growth phase without any requirement for up-regulation of transmembrane ammonium transporters. Optimization of cellular nutrient acquisition strategies can substantially improve performance in terms of growth, metabolism and stress resistance.

  1. The Ras GTPase-activating protein Rasal3 supports survival of naive T cells.

    Ryunosuke Muro

    Full Text Available The Ras-mitogen-activated protein kinase (MAPK pathway is crucial for T cell receptor (TCR signaling in the development and function of T cells. The significance of various modulators of the Ras-MAPK pathway in T cells, however, remains to be fully understood. Ras-activating protein-like 3 (Rasal3 is an uncharacterized member of the SynGAP family that contains a conserved Ras GTPase-activating protein (GAP domain, and is predominantly expressed in the T cell lineage. In the current study, we investigated the function and physiological roles of Rasal3. Our results showed that Rasal3 possesses RasGAP activity, but not Rap1GAP activity, and represses TCR-stimulated ERK phosphorylation in a T cell line. In systemic Rasal3-deficient mice, T cell development in the thymus including positive selection, negative selection, and β-selection was unaffected. However, the number of naive, but not effector memory CD4 and CD8 T cell in the periphery was significantly reduced in Rasal3-deficient mice, and associated with a marked increase in apoptosis of these cells. Indeed, survival of Rasal3 deficient naive CD4 T cells in vivo by adoptive transfer was significantly impaired, whereas IL-7-dependent survival of naive CD4 T cells in vitro was unaltered. Collectively, Rasal3 is required for in vivo survival of peripheral naive T cells, contributing to the maintenance of optimal T cell numbers.

  2. Metabolic and physiologic studies of nonimmune lymphoid cells cytotoxic for fibroblastic cells in vitro

    Mayhew, E.; Bennett, M.

    1974-01-01

    An in vitro reaction between mouse lymphoid cells and target fibroblastic cells in wells of microtest plates, which appears to simulate the in vivo rejection of hemopoietic allografts, has been analyzed for metabolic and physiologic requirements. Protein synthesis was required for only the first few hours of culture. Inhibition of RNA synthesis and alteration of cell surface charge with various agents were without obvious effects. Metabolic slowing at 4 0 C or deviation of the pH of the culture medium suppressed the reaction. Thymus cells, which are not cytotoxic in this system, significantly but not completely inhibited the cytotoxicity of lymph node cells. Antiserum directed against target cells specifically protected them from the cytotoxic lymphoid cells in the absence of complement. Precursors of cytotoxic lymphoid cells were radiosensitive, unlike the cytotoxic cells themselves. BALB/c anti-C57BL/6 spleen cell serum and 89 Sr both are able to prevent rejection of marrow allografts in vivo. Lymphoid cells incubated with this antiserum plus complement lost much of their cytotoxicity but were still effective at high ratios of aggressor to target cells. Lymphoid cells of mice treated with 89 Sr were effectively cytotoxic but lost practically all of their cytotoxicity after incubation with the antiserum plus complement. Thus, it appears that this reaction detects two different cytotoxic lymphoid cells, either of which can function in vitro. Both cell types may need to cooperate in vivo during marrow allograft rejections

  3. Cell-Intrinsic Glycogen Metabolism Supports Early Glycolytic Reprogramming Required for Dendritic Cell Immune Responses.

    Thwe, Phyu M; Pelgrom, Leonard; Cooper, Rachel; Beauchamp, Saritha; Reisz, Julie A; D'Alessandro, Angelo; Everts, Bart; Amiel, Eyal

    2017-09-05

    Dendritic cell (DC) activation by Toll-like receptor (TLR) agonists causes rapid glycolytic reprogramming that is required to meet the metabolic demands of their immune activation. Recent efforts in the field have identified an important role for extracellular glucose sourcing to support DC activation. However, the contributions of intracellular glucose stores to these processes have not been well characterized. We demonstrate that DCs possess intracellular glycogen stores and that cell-intrinsic glycogen metabolism supports the early effector functions of TLR-activated DCs. Inhibition of glycogenolysis significantly attenuates TLR-mediated DC maturation and impairs their ability to initiate lymphocyte activation. We further report that DCs exhibit functional compartmentalization of glucose- and glycogen-derived carbons, where these substrates preferentially contribute to distinct metabolic pathways. This work provides novel insights into nutrient homeostasis in DCs, demonstrating that differential utilization of glycogen and glucose metabolism regulates their optimal immune function. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Sox2 promotes survival of satellite glial cells in vitro

    Koike, Taro; Wakabayashi, Taketoshi; Mori, Tetsuji; Hirahara, Yukie; Yamada, Hisao

    2015-01-01

    Sox2 is a transcriptional factor expressed in neural stem cells. It is known that Sox2 regulates cell differentiation, proliferation and survival of the neural stem cells. Our previous study showed that Sox2 is expressed in all satellite glial cells of the adult rat dorsal root ganglion. In this study, to examine the role of Sox2 in satellite glial cells, we establish a satellite glial cell-enriched culture system. Our culture method succeeded in harvesting satellite glial cells with the somata of neurons in the dorsal root ganglion. Using this culture system, Sox2 was downregulated by siRNA against Sox2. The knockdown of Sox2 downregulated ErbB2 and ErbB3 mRNA at 2 and 4 days after siRNA treatment. MAPK phosphorylation, downstream of ErbB, was also inhibited by Sox2 knockdown. Because ErbB2 and ErbB3 are receptors that support the survival of glial cells in the peripheral nervous system, apoptotic cells were also counted. TUNEL-positive cells increased at 5 days after siRNA treatment. These results suggest that Sox2 promotes satellite glial cell survival through the MAPK pathway via ErbB receptors. - Highlights: • We established satellite glial cell culture system. • Function of Sox2 in satellite glial cell was examined using siRNA. • Sox2 knockdown downregulated expression level of ErbB2 and ErbB3 mRNA. • Sox2 knockdown increased apoptotic satellite glial cell. • Sox2 promotes satellite glial cell survival through ErbB signaling

  5. Sox2 promotes survival of satellite glial cells in vitro

    Koike, Taro, E-mail: koiket@hirakata.kmu.ac.jp; Wakabayashi, Taketoshi; Mori, Tetsuji; Hirahara, Yukie; Yamada, Hisao

    2015-08-14

    Sox2 is a transcriptional factor expressed in neural stem cells. It is known that Sox2 regulates cell differentiation, proliferation and survival of the neural stem cells. Our previous study showed that Sox2 is expressed in all satellite glial cells of the adult rat dorsal root ganglion. In this study, to examine the role of Sox2 in satellite glial cells, we establish a satellite glial cell-enriched culture system. Our culture method succeeded in harvesting satellite glial cells with the somata of neurons in the dorsal root ganglion. Using this culture system, Sox2 was downregulated by siRNA against Sox2. The knockdown of Sox2 downregulated ErbB2 and ErbB3 mRNA at 2 and 4 days after siRNA treatment. MAPK phosphorylation, downstream of ErbB, was also inhibited by Sox2 knockdown. Because ErbB2 and ErbB3 are receptors that support the survival of glial cells in the peripheral nervous system, apoptotic cells were also counted. TUNEL-positive cells increased at 5 days after siRNA treatment. These results suggest that Sox2 promotes satellite glial cell survival through the MAPK pathway via ErbB receptors. - Highlights: • We established satellite glial cell culture system. • Function of Sox2 in satellite glial cell was examined using siRNA. • Sox2 knockdown downregulated expression level of ErbB2 and ErbB3 mRNA. • Sox2 knockdown increased apoptotic satellite glial cell. • Sox2 promotes satellite glial cell survival through ErbB signaling.

  6. Lymphatic endothelial S1P promotes mitochondrial function and survival in naive T cells.

    Mendoza, Alejandra; Fang, Victoria; Chen, Cynthia; Serasinghe, Madhavika; Verma, Akanksha; Muller, James; Chaluvadi, V Sai; Dustin, Michael L; Hla, Timothy; Elemento, Olivier; Chipuk, Jerry E; Schwab, Susan R

    2017-06-01

    Effective adaptive immune responses require a large repertoire of naive T cells that migrate throughout the body, rapidly identifying almost any foreign peptide. Because the production of T cells declines with age, naive T cells must be long-lived. However, it remains unclear how naive T cells survive for years while constantly travelling. The chemoattractant sphingosine 1-phosphate (S1P) guides T cell circulation among secondary lymphoid organs, including spleen, lymph nodes and Peyer's patches, where T cells search for antigens. The concentration of S1P is higher in circulatory fluids than in lymphoid organs, and the S1P 1 receptor (S1P 1 R) directs the exit of T cells from the spleen into blood, and from lymph nodes and Peyer's patches into lymph. Here we show that S1P is essential not only for the circulation of naive T cells, but also for their survival. Using transgenic mouse models, we demonstrate that lymphatic endothelial cells support the survival of T cells by secreting S1P via the transporter SPNS2, that this S1P signals through S1P 1 R on T cells, and that the requirement for S1P 1 R is independent of the established role of the receptor in guiding exit from lymph nodes. S1P signalling maintains the mitochondrial content of naive T cells, providing cells with the energy to continue their constant migration. The S1P signalling pathway is being targeted therapeutically to inhibit autoreactive T cell trafficking, and these findings suggest that it may be possible simultaneously to target autoreactive or malignant cell survival.

  7. Repair-dependent cell radiation survival and transformation: an integrated theory

    Sutherland, John C

    2014-01-01

    The repair-dependent model of cell radiation survival is extended to include radiation-induced transformations. The probability of transformation is presumed to scale with the number of potentially lethal damages that are repaired in a surviving cell or the interactions of such damages. The theory predicts that at doses corresponding to high survival, the transformation frequency is the sum of simple polynomial functions of dose; linear, quadratic, etc, essentially as described in widely used linear-quadratic expressions. At high doses, corresponding to low survival, the ratio of transformed to surviving cells asymptotically approaches an upper limit. The low dose fundamental- and high dose plateau domains are separated by a downwardly concave transition region. Published transformation data for mammalian cells show the high-dose plateaus predicted by the repair-dependent model for both ultraviolet and ionizing radiation. For the neoplastic transformation experiments that were analyzed, the data can be fit with only the repair-dependent quadratic function. At low doses, the transformation frequency is strictly quadratic, but becomes sigmodial over a wider range of doses. Inclusion of data from the transition region in a traditional linear-quadratic analysis of neoplastic transformation frequency data can exaggerate the magnitude of, or create the appearance of, a linear component. Quantitative analysis of survival and transformation data shows good agreement for ultraviolet radiation; the shapes of the transformation components can be predicted from survival data. For ionizing radiations, both neutrons and x-rays, survival data overestimate the transforming ability for low to moderate doses. The presumed cause of this difference is that, unlike UV photons, a single x-ray or neutron may generate more than one lethal damage in a cell, so the distribution of such damages in the population is not accurately described by Poisson statistics. However, the complete

  8. Survival outcomes following salvage surgery for oropharyngeal squamous cell carcinoma: systematic review.

    Kao, S S; Ooi, E H

    2018-04-01

    Recurrent oropharyngeal squamous cell carcinoma causes great morbidity and mortality. This systematic review analyses survival outcomes following salvage surgery for recurrent oropharyngeal squamous cell carcinoma. A comprehensive search of various electronic databases was conducted. Studies included patients with recurrent or residual oropharyngeal squamous cell carcinoma treated with salvage surgery. Primary outcomes were survival rates following salvage surgery. Secondary outcomes included time to recurrence, staging at time of recurrence, post-operative complications, and factors associated with mortality and recurrence. Methodological appraisal and data extraction were conducted as per Joanna Briggs Institute methodology. Eighteen articles were included. The two- and five-year survival rates of the patients were 52 per cent and 30 per cent respectively. Improvements in treatment modalities for recurrent oropharyngeal squamous cell carcinoma were associated with improvements in two-year overall survival rates, with minimal change to five-year overall survival rates. Various factors were identified as being associated with long-term overall survival, thus assisting clinicians in patient counselling and selection for salvage surgery.

  9. Parasitic infection improves survival from septic peritonitis by enhancing mast cell responses to bacteria in mice.

    Rachel E Sutherland

    Full Text Available Mammals are serially infected with a variety of microorganisms, including bacteria and parasites. Each infection reprograms the immune system's responses to re-exposure and potentially alters responses to first-time infection by different microorganisms. To examine whether infection with a metazoan parasite modulates host responses to subsequent bacterial infection, mice were infected with the hookworm-like intestinal nematode Nippostrongylus brasiliensis, followed in 2-4 weeks by peritoneal injection of the pathogenic bacterium Klebsiella pneumoniae. Survival from Klebsiella peritonitis two weeks after parasite infection was better in Nippostrongylus-infected animals than in unparasitized mice, with Nippostrongylus-infected mice having fewer peritoneal bacteria, more neutrophils, and higher levels of protective interleukin 6. The improved survival of Nippostrongylus-infected mice depends on IL-4 because the survival benefit is lost in mice lacking IL-4. Because mast cells protect mice from Klebsiella peritonitis, we examined responses in mast cell-deficient Kit(W-sh/Kit(W-sh mice, in which parasitosis failed to improve survival from Klebsiella peritonitis. However, adoptive transfer of cultured mast cells to Kit(W-sh/Kit(W-sh mice restored survival benefits of parasitosis. These results show that recent infection with Nippostrongylus brasiliensis protects mice from Klebsiella peritonitis by modulating mast cell contributions to host defense, and suggest more generally that parasitosis can yield survival advantages to a bacterially infected host.

  10. Clonogenic cell line survival of a human liver cancer cell line SMMC-7721 after carbon ion irradiation with different LET

    Lei Suwen; Su Xu; Wang Jifang; Li Wenjian

    2003-01-01

    Objective: To investigate the survival fraction of a human liver cancer cell line SMMC-7721 following irradiation with carbon ions with different LET. Methods: cells of the human liver cancer cell line SMMC-7721 were irradiated with carbon ions (LET=30 and 70 keV/μm). The survival fraction was determined with clonogenic assay after 9 days incubation in a 5% CO 2 incubator at 37 degree C. Results: When the survival fractions of 70 keV/μm were D s = 0.1 and D s=0.01 absorption dose were 2.94 and 5.88 Gy respectively, and those of 30 keV/μm were 4.00 and 8.00 Gy respectively. Conclusion: For the SMMC-7721 cell line, 70 keV/μm is more effective for cell killing than 30 keV/μm

  11. Survival of human osteosarcoma cells and normal human fibroblasts following alpha particle irradiation

    Lloyd, E.L.; Gemmell, M.A.

    1981-01-01

    Cell survival of human osteosarcoma cells in culture following alpha particle irradiation is reported here for the first time. The osteosarcoma cell line (TE-85) is found to be less sensitive to inactivation by 5.6 MeV alpha particles (LET 86 keV/μm) than normal diploid human fibroblasts (NFS). Values for the mean lethal doses were estimated to be 103 rads for the TE-85 cells compared with 68 rads for the NFS cultures irradiated under identical conditions. It is postulated that the aneuploidy of the tumor cells with increased DNA chromosomal material may confer a selective advantage for the survival of tumor cells relative to normal cells with diploid chromosomes

  12. The regulation of function, growth and survival of GLP-1-producing L-cells

    Kuhre, Rune Ehrenreich; Holst, Jens Juul; Kappe, Camilla

    2016-01-01

    that regulate the growth, survival and function of these cells are largely unknown. We recently showed that prolonged exposure to high concentrations of the fatty acid palmitate induced lipotoxic effects, similar to those operative in insulin-producing cells, in an in vitro model of GLP-1-producing cells...... absorption and disposal, as well as cell proliferation and survival. In Type 2 Diabetes (T2D) reduced plasma levels of GLP-1 have been observed, and plasma levels of GLP-1, as well as reduced numbers of GLP-1 producing cells, have been correlated to obesity and insulin resistance. Increasing endogenous...... secretion of GLP-1 by selective targeting of the molecular mechanisms regulating secretion from the L-cell has been the focus of much recent research. An additional and promising strategy for enhancing endogenous secretion may be to increase the L-cell mass in the intestinal epithelium, but the mechanisms...

  13. In silico-based identification of human α-enolase inhibitors to block cancer cell growth metabolically

    Lung, Jrhau; Chen, Kuan-Liang; Hung, Chien-Hui; Chen, Chih-Cheng; Hung, Ming-Szu; Lin, Yu-Ching; Wu, Ching-Yuan; Lee, Kuan-Der; Shih, Neng-Yao; Tsai, Ying Huang

    2017-01-01

    Unlimited growth of cancer cells requires an extensive nutrient supply. To meet this demand, cancer cells drastically upregulate glucose uptake and metabolism compared to normal cells. This difference has made the blocking of glycolysis a fascinating strategy to treat this malignant disease. α-enolase is not only one of the most upregulated glycolytic enzymes in cancer cells, but also associates with many cellular processes or conditions important to cancer cell survival, such as cell migration, invasion, and hypoxia. Targeting α-enolase could simultaneously disturb cancer cells in multiple ways and, therefore, is a good target for anticancer drug development. In the current study, more than 22 million chemical structures meeting the criteria of Lipinski’s rule of five from the ZINC database were docked to α-enolase by virtual screening. Twenty-four chemical structures with docking scores better than that of the enolase substrate, 2-phosphoglycerate, were further screened by the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties prediction. Four of them were classified as non-mutagenic, non-carcinogenic, and capable of oral administration where they showed steady interactions to α-enolase that were comparable, even superior, to the currently available inhibitors in molecular dynamics (MD) simulation. These compounds may be considered promising leads for further development of the α-enolase inhibitors and could help fight cancer metabolically. PMID:29180852

  14. Poly (ADP-ribose) metabolism in alkylated mouse L5178Y cells

    Boyle, J.M.

    1985-01-01

    Poly ADP-ribosylation of two mouse lymphoma cell lines, L5178Y (LS) and the radiation and alkylating agent resistant derivative AII, was investigated by uptake of [ 3 H]NAD by permeabilised cells into acid-precipitable material that was sensitive to phosphodiesterase but insensitive to DNase and RNase. Basal activities in both lymphoma lines were 3-4-fold greater than in mouse L1210 leukaemia cells. However, total endogenous poly (ADP-R) polymerase activity in both L5178Y cell lines, stimulated by a large excess of DNase in the presence of Triton X-100, was less than half the activity in L1210 cells. Doses of N-methyl-N-nitrosourea (MNU) that produced 20-50% survival of colony-forming units increased poly (ADP-R) in both lymphoma lines by only 25% compared with 377% in L1210 cells when synthesis was measured immediately after a 30-min exposure of MNU. Concentrations of 3-aminobenzamide (3AB) above 2.5 mM inhibited colony-forming ability of lymphoma cells and equally inhibited uptake of [ 14 C]formate into protein, RNA and DNA indicating that 3AB behaves as a general metabolic poison. Non-toxic concentrations of 3AB potentiated cell killing by MNU to a similar degree in both lymphoma cell lines. In conclusion, the authors have found little evidence to support the hypothesis that the differential sensitivity of LS and AII is related to poly ADP-ribosylation. Compared with other mouse cells, L5178Y cells appear deficient in poly (ADP-R) polymerase and poly (ADP-R) glycohydrolase activities

  15. N-methyl-D-aspartate promotes the survival of cerebellar granule cells in culture

    Balázs, R; Jørgensen, Ole Steen; Hack, N

    1988-01-01

    Our previous studies on the survival-promoting influence of elevated concentrations of extracellular K+ ([K+]e) on cultured cerebellar granule cells led to the proposal that depolarization in vitro mimics the effect of the earliest afferent inputs received by the granule cells in vivo. This, in t...

  16. Mitochondrial pyruvate carrier function determines cell stemness and metabolic reprogramming in cancer cells

    Li, Xiaoran; Kan, Quancheng; Fan, Zhirui; Li, Yaqing; Ji, Yasai; Zhao, Jing; Zhang, Mingzhi; Grigalavicius, Mantas; Berge, Viktor; Goscinski, Mariusz Adam; M. Nesland, Jahn; Suo, Zhenhe

    2017-01-01

    One of the remarkable features of cancer cells is aerobic glycolysis, a phenomenon known as the “Warburg Effect”, in which cells rely preferentially on glycolysis instead of oxidative phosphorylation (OXPHOS) as the main energy source even in the presence of high oxygen tension. Cells with dysfunctional mitochondria are unable to generate sufficient ATP from mitochondrial OXPHOS, and then are forced to rely on glycolysis for ATP generation. Here we report our results in a prostate cancer cell line in which the mitochondrial pyruvate carrier 1 (MPC1) gene was knockout. It was discovered that the MPC1 gene knockout cells revealed a metabolism reprogramming to aerobic glycolysis with reduced ATP production, and the cells became more migratory and resistant to both chemotherapy and radiotherapy. In addition, the MPC1 knockout cells expressed significantly higher levels of the stemness markers Nanog, Hif1α, Notch1, CD44 and ALDH. To further verify the correlation of MPC gene function and cell stemness/metabolic reprogramming, MPC inhibitor UK5099 was applied in two ovarian cancer cell lines and similar results were obtained. Taken together, our results reveal that functional MPC may determine the fate of metabolic program and the stemness status of cancer cells in vitro. PMID:28624784

  17. Thymidine kinase 1 deficient cells show increased survival rate after UV-induced DNA damage

    Skovgaard, T; Rasmussen, Lene Juel; Munch-Petersen, Birgitte

    2010-01-01

    Balanced deoxynucleotide pools are known to be important for correct DNA repair, and deficiency for some of the central enzymes in deoxynucleotide metabolism can cause imbalanced pools, which in turn can lead to mutagenesis and cell death. Here we show that cells deficient for the thymidine salva...

  18. DOCK8 is critical for the survival and function of NKT cells.

    Crawford, Greg; Enders, Anselm; Gileadi, Uzi; Stankovic, Sanda; Zhang, Qian; Lambe, Teresa; Crockford, Tanya L; Lockstone, Helen E; Freeman, Alexandra; Arkwright, Peter D; Smart, Joanne M; Ma, Cindy S; Tangye, Stuart G; Goodnow, Christopher C; Cerundolo, Vincenzo; Godfrey, Dale I; Su, Helen C; Randall, Katrina L; Cornall, Richard J

    2013-09-19

    Patients with the dedicator of cytokinesis 8 (DOCK8) immunodeficiency syndrome suffer from recurrent viral and bacterial infections, hyper-immunoglobulin E levels, eczema, and greater susceptibility to cancer. Because natural killer T (NKT) cells have been implicated in these diseases, we asked if these cells were affected by DOCK8 deficiency. Using a mouse model, we found that DOCK8 deficiency resulted in impaired NKT cell development, principally affecting the formation and survival of long-lived, differentiated NKT cells. In the thymus, DOCK8-deficient mice lack a terminally differentiated subset of NK1.1(+) NKT cells expressing the integrin CD103, whereas in the liver, DOCK8-deficient NKT cells express reduced levels of the prosurvival factor B-cell lymphoma 2 and the integrin lymphocyte function-associated antigen 1. Although the initial NKT cell response to antigen is intact in the absence of DOCK8, their ongoing proliferative and cytokine responses are impaired. Importantly, a similar defect in NKT cell numbers was detected in DOCK8-deficient humans, highlighting the relevance of the mouse model. In conclusion, our data demonstrate that DOCK8 is required for the development and survival of mature NKT cells, consistent with the idea that DOCK8 mediates survival signals within a specialized niche. Accordingly, impaired NKT cell numbers and function are likely to contribute to the susceptibility of DOCK8-deficient patients to recurrent infections and malignant disease.

  19. DOCK8 is critical for the survival and function of NKT cells

    Crawford, Greg; Enders, Anselm; Gileadi, Uzi; Stankovic, Sanda; Zhang, Qian; Lambe, Teresa; Crockford, Tanya L.; Lockstone, Helen E.; Freeman, Alexandra; Arkwright, Peter D.; Smart, Joanne M.; Ma, Cindy S.; Tangye, Stuart G.; Goodnow, Christopher C.; Cerundolo, Vincenzo; Godfrey, Dale I.; Su, Helen C.; Randall, Katrina L.

    2013-01-01

    Patients with the dedicator of cytokinesis 8 (DOCK8) immunodeficiency syndrome suffer from recurrent viral and bacterial infections, hyper–immunoglobulin E levels, eczema, and greater susceptibility to cancer. Because natural killer T (NKT) cells have been implicated in these diseases, we asked if these cells were affected by DOCK8 deficiency. Using a mouse model, we found that DOCK8 deficiency resulted in impaired NKT cell development, principally affecting the formation and survival of long-lived, differentiated NKT cells. In the thymus, DOCK8-deficient mice lack a terminally differentiated subset of NK1.1+ NKT cells expressing the integrin CD103, whereas in the liver, DOCK8-deficient NKT cells express reduced levels of the prosurvival factor B-cell lymphoma 2 and the integrin lymphocyte function-associated antigen 1. Although the initial NKT cell response to antigen is intact in the absence of DOCK8, their ongoing proliferative and cytokine responses are impaired. Importantly, a similar defect in NKT cell numbers was detected in DOCK8-deficient humans, highlighting the relevance of the mouse model. In conclusion, our data demonstrate that DOCK8 is required for the development and survival of mature NKT cells, consistent with the idea that DOCK8 mediates survival signals within a specialized niche. Accordingly, impaired NKT cell numbers and function are likely to contribute to the susceptibility of DOCK8-deficient patients to recurrent infections and malignant disease. PMID:23929855

  20. EEN regulates the proliferation and survival of multiple myeloma cells by potentiating IGF-1 secretion

    Huang, Er-Wen; Xue, Sheng-Jiang; Li, Xiao-Yan; Xu, Suo-Wen; Cheng, Jian-Ding; Zheng, Jin-Xiang; Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong; Li, Jie; Liu, Chao

    2014-01-01

    Highlights: • Levels of EEN expression paralleled with the rate of cell proliferation. • EEN was involved in the proliferation and survival of multiple myeloma (MM) cells. • EEN regulated the activity of IGF-1-Akt/mTOR pathway. • EEN regulated proliferation and survival of MM cells by enhancing IGF-1 secretion. - Abstract: The molecular mechanisms of multiple myeloma are not well defined. EEN is an endocytosis-regulating molecule. Here we report that EEN regulates the proliferation and survival of multiple myeloma cells, by regulating IGF-1 secretion. In the present study, we observed that EEN expression paralleled with cell proliferation, EEN accelerated cell proliferation, facilitated cell cycle transition from G1 to S phase by regulating cyclin-dependent kinases (CDKs) pathway, and delayed cell apoptosis via Bcl2/Bax-mitochondrial pathway. Mechanistically, we found that EEN was indispensable for insulin-like growth factor-1 (IGF-1) secretion and the activation of protein kinase B-mammalian target of rapamycin (Akt-mTOR) pathway. Exogenous IGF-1 overcame the phenotype of EEN depletion, while IGF-1 neutralization overcame that of EEN over-expression. Collectively, these data suggest that EEN may play a pivotal role in excessive cell proliferation and insufficient cell apoptosis of bone marrow plasma cells in multiple myeloma. Therefore, EEN may represent a potential diagnostic marker or therapeutic target for multiple myeloma

  1. EEN regulates the proliferation and survival of multiple myeloma cells by potentiating IGF-1 secretion

    Huang, Er-Wen [Guangzhou Institute of Forensic Science, Guangzhou (China); Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Xue, Sheng-Jiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Li, Xiao-Yan [Department of Pharmacy, The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China); Xu, Suo-Wen [Department of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou (China); Cheng, Jian-Ding; Zheng, Jin-Xiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong [Guangzhou Institute of Forensic Science, Guangzhou (China); Li, Jie, E-mail: mdlijie@sina.com [Department of Anaesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou (China); Liu, Chao, E-mail: liuchaogaj@21cn.com [Guangzhou Institute of Forensic Science, Guangzhou (China)

    2014-05-02

    Highlights: • Levels of EEN expression paralleled with the rate of cell proliferation. • EEN was involved in the proliferation and survival of multiple myeloma (MM) cells. • EEN regulated the activity of IGF-1-Akt/mTOR pathway. • EEN regulated proliferation and survival of MM cells by enhancing IGF-1 secretion. - Abstract: The molecular mechanisms of multiple myeloma are not well defined. EEN is an endocytosis-regulating molecule. Here we report that EEN regulates the proliferation and survival of multiple myeloma cells, by regulating IGF-1 secretion. In the present study, we observed that EEN expression paralleled with cell proliferation, EEN accelerated cell proliferation, facilitated cell cycle transition from G1 to S phase by regulating cyclin-dependent kinases (CDKs) pathway, and delayed cell apoptosis via Bcl2/Bax-mitochondrial pathway. Mechanistically, we found that EEN was indispensable for insulin-like growth factor-1 (IGF-1) secretion and the activation of protein kinase B-mammalian target of rapamycin (Akt-mTOR) pathway. Exogenous IGF-1 overcame the phenotype of EEN depletion, while IGF-1 neutralization overcame that of EEN over-expression. Collectively, these data suggest that EEN may play a pivotal role in excessive cell proliferation and insufficient cell apoptosis of bone marrow plasma cells in multiple myeloma. Therefore, EEN may represent a potential diagnostic marker or therapeutic target for multiple myeloma.

  2. Frozen in Time? Microbial strategies for survival and carbon metabolism over geologic time in a Pleistocene permafrost chronosequence

    Mackelprang, R.; Douglas, T. A.; Waldrop, M. P.

    2014-12-01

    Permafrost soils have received tremendous interest due to their importance as a global carbon store with the potential to be thawed over the coming centuries. Instead of being 'frozen in time,' permafrost contains active microbes. Most metagenomic studies have focused on Holocene aged permafrost. Here, we target Pleistocene aged ice and carbon rich permafrost (Yedoma), which can differ in carbon content and stage of decay. Our aim was to understand how microbes in the permafrost transform organic matter over geologic time and to identify physiological and biochemical adaptations that enable long-term survival. We used next-generation sequencing to characterize microbial communities along a permafrost age gradient. Samples were collected from the Cold Regions Research and Engineering Laboratory (CRREL) Permafrost Tunnel near Fox, AK, which penetrates a hillside providing access to permafrost ranging in age from 12 to 40 kyr. DNA was extracted directly from unthawed samples. 16S rRNA amplicon (16S) and shotgun metagenome sequencing revealed significant age-driven differences. First, microbial diversity declines with permafrost age, likely due to long-term exposure to environmental stresses and a reduction in metabolic resources. Second, we observed taxonomic differences among ages, with an increasing abundance of Firmicutes (endospore-formers) in older samples, suggesting that dormancy is a common survival strategy in older permafrost. Ordination of 16S and metagenome data revealed age-based clustering. Genes differing significantly between age categories included those involved in lipopolysaccharide assembly, cold-response, and carbon processing. These data point to the physiological adaptations to long-term frozen conditions and to the metabolic processes utilized in ancient permafrost. In fact, a gene common in older samples is involved in cadaverine production, which could potentially explain the putrefied smell of Pleistocene aged permafrost. Coupled with soil

  3. Brassinosteroid regulates cell elongation by modulating gibberellin metabolism in rice.

    Tong, Hongning; Xiao, Yunhua; Liu, Dapu; Gao, Shaopei; Liu, Linchuan; Yin, Yanhai; Jin, Yun; Qian, Qian; Chu, Chengcai

    2014-11-01

    Brassinosteroid (BR) and gibberellin (GA) are two predominant hormones regulating plant cell elongation. A defect in either of these leads to reduced plant growth and dwarfism. However, their relationship remains unknown in rice (Oryza sativa). Here, we demonstrated that BR regulates cell elongation by modulating GA metabolism in rice. Under physiological conditions, BR promotes GA accumulation by regulating the expression of GA metabolic genes to stimulate cell elongation. BR greatly induces the expression of D18/GA3ox-2, one of the GA biosynthetic genes, leading to increased GA1 levels, the bioactive GA in rice seedlings. Consequently, both d18 and loss-of-function GA-signaling mutants have decreased BR sensitivity. When excessive active BR is applied, the hormone mostly induces GA inactivation through upregulation of the GA inactivation gene GA2ox-3 and also represses BR biosynthesis, resulting in decreased hormone levels and growth inhibition. As a feedback mechanism, GA extensively inhibits BR biosynthesis and the BR response. GA treatment decreases the enlarged leaf angles in plants with enhanced BR biosynthesis or signaling. Our results revealed a previously unknown mechanism underlying BR and GA crosstalk depending on tissues and hormone levels, which greatly advances our understanding of hormone actions in crop plants and appears much different from that in Arabidopsis thaliana. © 2014 American Society of Plant Biologists. All rights reserved.

  4. Are natural killer cells protecting the metabolically healthy obese patient?

    Lynch, Lydia A

    2012-02-01

    With the emerging obesity pandemic, identifying those who appear to be protected from adverse consequences such as type 2 diabetes and certain malignancies will become important. We propose that the circulating immune system plays a role in the development of these comorbidities. Clinical data and blood samples were collected from 52 patients with severe obesity attending a hospital weight-management clinic and 11 lean healthy controls. Patients were classified into metabolically "healthy obese" (n = 26; mean age 42.6 years, mean BMI 46.8 kg\\/m(2)) or "unhealthy obese" (n = 26; mean age 45 years, mean BMI 47.5 kg\\/m(2)) groups, based upon standard cutoff points for blood pressure, lipid profile, and fasting glucose. Circulating lymphoid populations and phenotypes were assessed by flow cytometry. Obese patients had significantly less circulating natural killer (NK) and cytotoxic T lymphocytes (CTL) compared to lean controls. There were significantly higher levels of NK cells and CTLs in the healthy obese group compared to the unhealthy obese group (NK: 11.7% vs. 6.5%, P < 0.0001, CD8 13.4% vs. 9.3%, P = 0.04), independent of age and BMI and these NK cells were also less activated in the healthy compared to the unhealthy group (CD69, 4.1% vs. 11.8%, P = 0.03). This is the first time that quantitative differences in the circulating immune system of obese patients with similar BMI but different metabolic profiles have been described. The significantly higher levels of CTLs and NK cells, which express fewer inhibitory molecules, could protect against malignancy, infection, and metabolic disease seen in obesity.

  5. Dose-rate dependent stochastic effects in radiation cell-survival models

    Sachs, R.K.; Hlatky, L.R.

    1990-01-01

    When cells are subjected to ionizing radiation the specific energy rate (microscopic analog of dose-rate) varies from cell to cell. Within one cell, this rate fluctuates during the course of time; a crossing of a sensitive cellular site by a high energy charged particle produces many ionizations almost simultaneously, but during the interval between events no ionizations occur. In any cell-survival model one can incorporate the effect of such fluctuations without changing the basic biological assumptions. Using stochastic differential equations and Monte Carlo methods to take into account stochastic effects we calculated the dose-survival rfelationships in a number of current cell survival models. Some of the models assume quadratic misrepair; others assume saturable repair enzyme systems. It was found that a significant effect of random fluctuations is to decrease the theoretically predicted amount of dose-rate sparing. In the limit of low dose-rates neglecting the stochastic nature of specific energy rates often leads to qualitatively misleading results by overestimating the surviving fraction drastically. In the opposite limit of acute irradiation, analyzing the fluctuations in rates merely amounts to analyzing fluctuations in total specific energy via the usual microdosimetric specific energy distribution function, and neglecting fluctuations usually underestimates the surviving fraction. The Monte Carlo methods interpolate systematically between the low dose-rate and high dose-rate limits. As in other approaches, the slope of the survival curve at low dose-rates is virtually independent of dose and equals the initial slope of the survival curve for acute radiation. (orig.)

  6. Correlation of hedgehog signal activation with chemoradiotherapy sensitivity and survival in esophageal squamous cell carcinomas

    Zhu Weiguo; You Zhenbin; Li Tao; Yu Changhua; Tao Guangzhou; Hu Mingli; Chen Xiaofei

    2011-01-01

    The objective of this study was to investigate the significance of hedgehog signaling pathway in chemoradiotherapy sensitivity and its effect on the prognosis of esophageal squamous cell carcinoma. In the present study, we used the method of immunohistochemistry to examine the expression status of two hedgehog components, PTCH1 and glioma-associated oncogene GLI-1, in 100 pre-treated biopsy specimens of esophageal squamous cell carcinoma patients treated with definitive chemoradiotherapy. We find that high levels of PTCH1 and GLI-1 were detected in 76.0 and 72.0% of esophageal squamous cell carcinoma, respectively. Significant associations of high PTCH1 and GLI-1 expression with large tumor size (both P=0.01), locoregional progression (P=0.001 and 0.003, respectively) and the lack of complete response to chemoradiotherapy (P=0.008 and 0.01, respectively) were observed. Univariate analysis revealed that high PTCH1 and GLI-1 expression was associated with poor locoregional progression-free survival, distant progression-free survival and overall survival. Furthermore, esophageal squamous cell carcinoma patients with high PTCH1 and GLI-1 expression have the shorter survival time than the subgroups with negative and low PTCH1 and GLI-1 expression. In multivariate analysis, PTCH1 and GLI-1 expression status were both evaluated as independent prognostic factors for locoregional progression-free survival, distant progression-free survival and overall survival. These findings suggest an important role for the activation of hedgehog signaling in esophageal squamous cell carcinoma progression and that PTCH1 and GLI-1 expression may be significantly associated with esophageal squamous cell carcinoma resistance to chemoradiotherapy. (author)

  7. A naringenin–tamoxifen combination impairs cell proliferation and survival of MCF-7 breast cancer cells

    Hatkevich, Talia; Ramos, Joseph; Santos-Sanchez, Idalys; Patel, Yashomati M., E-mail: ympatel@uncg.edu

    2014-10-01

    Since over 60% of breast cancers are estrogen receptor positive (ER+), many therapies have targeted the ER. The ER is activated by both estrogen binding and phosphorylation. While anti-estrogen therapies, such as tamoxifen (Tam) have been successful they do not target the growth factor promoting phosphorylation of the ER. Other proliferation pathways such as the phosphatidylinositol-3 kinase, (PI3K) and the mitogen-activated protein kinase (MAPK) pathways are activated in breast cancer cells and are associated with poor prognosis. Thus targeting multiple cellular proliferation and survival pathways at the onset of treatment is critical for the development of more effective therapies. The grapefruit flavanone naringenin (Nar) is an inhibitor of both the PI3K and MAPK pathways. Previous studies examining either Nar or Tam used charcoal-stripped serum which removed estrogen as well as other factors. We wanted to use serum containing medium in order to retain all the potential inducers of cell proliferation so as not to exclude any targets of Nar. Here we show that a Nar–Tam combination is more effective than either Tam alone or Nar alone in MCF-7 breast cancer cells. We demonstrate that a Nar–Tam combination impaired cellular proliferation and viability to a greater extent than either component alone in MCF-7 cells. Furthermore, the use of a Nar–Tam combination requires lower concentrations of both compounds to achieve the same effects on proliferation and viability. Nar may function by inhibiting both PI3K and MAPK pathways as well as localizing ERα to the cytoplasm in MCF-7 cells. Our results demonstrate that a Nar–Tam combination induces apoptosis and impairs proliferation signaling to a greater extent than either compound alone. These studies provide critical information for understanding the molecular mechanisms involved in cell proliferation and apoptosis in breast cancer cells. - Highlights: • Nar–Tam impairs cell viability more effectively than

  8. A naringenin–tamoxifen combination impairs cell proliferation and survival of MCF-7 breast cancer cells

    Hatkevich, Talia; Ramos, Joseph; Santos-Sanchez, Idalys; Patel, Yashomati M.

    2014-01-01

    Since over 60% of breast cancers are estrogen receptor positive (ER+), many therapies have targeted the ER. The ER is activated by both estrogen binding and phosphorylation. While anti-estrogen therapies, such as tamoxifen (Tam) have been successful they do not target the growth factor promoting phosphorylation of the ER. Other proliferation pathways such as the phosphatidylinositol-3 kinase, (PI3K) and the mitogen-activated protein kinase (MAPK) pathways are activated in breast cancer cells and are associated with poor prognosis. Thus targeting multiple cellular proliferation and survival pathways at the onset of treatment is critical for the development of more effective therapies. The grapefruit flavanone naringenin (Nar) is an inhibitor of both the PI3K and MAPK pathways. Previous studies examining either Nar or Tam used charcoal-stripped serum which removed estrogen as well as other factors. We wanted to use serum containing medium in order to retain all the potential inducers of cell proliferation so as not to exclude any targets of Nar. Here we show that a Nar–Tam combination is more effective than either Tam alone or Nar alone in MCF-7 breast cancer cells. We demonstrate that a Nar–Tam combination impaired cellular proliferation and viability to a greater extent than either component alone in MCF-7 cells. Furthermore, the use of a Nar–Tam combination requires lower concentrations of both compounds to achieve the same effects on proliferation and viability. Nar may function by inhibiting both PI3K and MAPK pathways as well as localizing ERα to the cytoplasm in MCF-7 cells. Our results demonstrate that a Nar–Tam combination induces apoptosis and impairs proliferation signaling to a greater extent than either compound alone. These studies provide critical information for understanding the molecular mechanisms involved in cell proliferation and apoptosis in breast cancer cells. - Highlights: • Nar–Tam impairs cell viability more effectively than

  9. STAT signaling in mammary gland differentiation, cell survival and tumorigenesis.

    Haricharan, S; Li, Y

    2014-01-25

    The mammary gland is a unique organ that undergoes extensive and profound changes during puberty, menstruation, pregnancy, lactation and involution. The changes that take place during puberty involve large-scale proliferation and invasion of the fat-pad. During pregnancy and lactation, the mammary cells are exposed to signaling pathways that inhibit apoptosis, induce proliferation and invoke terminal differentiation. Finally, during involution the mammary gland is exposed to milk stasis, programmed cell death and stromal reorganization to clear the differentiated milk-producing cells. Not surprisingly, the signaling pathways responsible for bringing about these changes in breast cells are often subverted during the process of tumorigenesis. The STAT family of proteins is involved in every stage of mammary gland development, and is also frequently implicated in breast tumorigenesis. While the roles of STAT3 and STAT5 during mammary gland development and tumorigenesis are well studied, others members, e.g. STAT1 and STAT6, have only recently been observed to play a role in mammary gland biology. Continued investigation into the STAT protein network in the mammary gland will likely yield new biomarkers and risk factors for breast cancer, and may also lead to novel prophylactic or therapeutic strategies against breast cancer. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Metabolically engineered cells for the production of polyunsaturated fatty acids

    2005-01-01

    The present invention relates to the construction and engineering of cells, more particularly microorganisms for producing PUFAs with four or more double bonds from non-fatty acid substrates through heterologous expression of an oxygen requiring pathway. The invention especially involves...... improvement of the PUFA content in the host organism through fermentation optimization, e.g. decreasing the temperature and/or designing an optimal medium, or through improving the flux towards fatty acids by metabolic engineering, e.g. through over-expression of fatty acid synthases, over-expression of other...

  11. Cholesterol metabolism in blood cells of irradiated rats

    Novoselova, E.G.; Kulagina, T.P.; Potekhina, N.I.

    1985-01-01

    Cholesterol metabolism in blood erythrocytes and lymphocytes of irradiated rats has been investigated. It has been found that at all terms and doses of irradiation, a suppression of the synthesis of erythrocyte cholesterol is observed. The increase of cholesterol quantiy in erythrocytes upon total gamma irradiation in the 10 Gr dose possibly is the result of growth of cholesterol transfer from plasma into erythrocyte cells. The study of the cholesterol synthesis in suspension of lymphocytes elminated from peripheral blood of control and irradiated rats has shown that at irradiation doses of 4 and 10 Gr in an hour acivation of cholesterol synthesis in vitro takes places

  12. Cell Wall Metabolism in Response to Abiotic Stress

    Gall, Hyacinthe Le; Philippe, Florian; Domon, Jean-Marc; Gillet, Françoise; Pelloux, Jérôme; Rayon, Catherine

    2015-01-01

    This review focuses on the responses of the plant cell wall to several abiotic stresses including drought, flooding, heat, cold, salt, heavy metals, light, and air pollutants. The effects of stress on cell wall metabolism are discussed at the physiological (morphogenic), transcriptomic, proteomic and biochemical levels. The analysis of a large set of data shows that the plant response is highly complex. The overall effects of most abiotic stress are often dependent on the plant species, the genotype, the age of the plant, the timing of the stress application, and the intensity of this stress. This shows the difficulty of identifying a common pattern of stress response in cell wall architecture that could enable adaptation and/or resistance to abiotic stress. However, in most cases, two main mechanisms can be highlighted: (i) an increased level in xyloglucan endotransglucosylase/hydrolase (XTH) and expansin proteins, associated with an increase in the degree of rhamnogalacturonan I branching that maintains cell wall plasticity and (ii) an increased cell wall thickening by reinforcement of the secondary wall with hemicellulose and lignin deposition. Taken together, these results show the need to undertake large-scale analyses, using multidisciplinary approaches, to unravel the consequences of stress on the cell wall. This will help identify the key components that could be targeted to improve biomass production under stress conditions. PMID:27135320

  13. Foxp1 controls mature B cell survival and the development of follicular and B-1 B cells

    Patzelt, Thomas; Keppler, Selina J.; Gorka, Oliver; Thoene, Silvia; Wartewig, Tim; Reth, Michael; Förster, Irmgard; Lang, Roland; Buchner, Maike; Ruland, Jürgen

    2018-01-01

    The transcription factor Foxp1 is critical for early B cell development. Despite frequent deregulation of Foxp1 in B cell lymphoma, the physiological functions of Foxp1 in mature B cells remain unknown. Here, we used conditional gene targeting in the B cell lineage and report that Foxp1 disruption in developing and mature B cells results in reduced numbers and frequencies of follicular and B-1 B cells and in impaired antibody production upon T cell-independent immunization in vivo. Moreover, Foxp1-deficient B cells are impaired in survival even though they exhibit an increased capacity to proliferate. Transcriptional analysis identified defective expression of the prosurvival Bcl-2 family gene Bcl2l1 encoding Bcl-xl in Foxp1-deficient B cells, and we identified Foxp1 binding in the regulatory region of Bcl2l1. Transgenic overexpression of Bcl2 rescued the survival defect in Foxp1-deficient mature B cells in vivo and restored peripheral B cell numbers. Thus, our results identify Foxp1 as a physiological regulator of mature B cell survival mediated in part via the control of Bcl-xl expression and imply that this pathway might contribute to the pathogenic function of aberrant Foxp1 expression in lymphoma. PMID:29507226

  14. Effects of various metals on survival, growth, reproduction, and metabolism of Daphnia magna

    Biesinger, K E; Christensen, G M

    1972-01-01

    The toxicities of various metals to Daphnia magna were evaluated on the basis of a 48-hr 50% lethal concentration (lc50) 3-week 16% reproductive impairment concentrations (In micrograms per liter) for the metal ions tested were: Na(I), 680,000; Ca(II), 116,000; Mg(II), 82,000; K(I), 53,000; Sr(II), 42,000; Ba(II), 5,800; Fe(III), 4,380; Mn(II), 4,100; As(V), 520; Sn(II), 350; Cr(III), 330; Al(III), 320; Zn(II), 70; Au(III), 60; Ni(II), 30; Pb(II), 30; Cu(II), 22; Pt(IV), 14; Co(II), 10; Hg(II), 3.4; and Cd(II), 0.17. At mental concentrations permitting survival but impairing reproduction, daphnids weighed less than control animals. Amounts of total protein and glutamic oxalacetic transaminase activity varied with the different metals. The negative logarithm of the solubility product constant 8 pksp of the metal sulfides, electronegativity, and the logarithm of the equilibrium constant (log keg) of the metal-ATP complex were positively correlated with toxicity to D. magna. Other physicochemical properties were considered, but no additional correlations were found.

  15. Tumor cell survival dependence on helical tomotherapy, continuous arc and segmented dose delivery

    Yang Wensha; Wang Li; Larner, James; Read, Paul; Benedict, Stan; Sheng Ke

    2009-01-01

    The temporal pattern of radiation delivery has been shown to influence the tumor cell survival fractions for the same radiation dose. To study the effect more specifically for state of the art rotational radiation delivery modalities, 2 Gy of radiation dose was delivered to H460 lung carcinoma, PC3 prostate cancer cells and MCF-7 breast tumor cells by helical tomotherapy (HT), seven-field LINAC (7F), and continuous dose delivery (CDD) over 2 min that simulates volumetric rotational arc therapy. Cell survival was measured by the clonogenic assay. The number of viable H460 cell colonies was 23.2 ± 14.4% and 27.7 ± 15.6% lower when irradiated by CDD compared with HT and 7F, respectively, and the corresponding values were 36.8 ± 18.9% and 35.3 ± 18.9% lower for MCF7 cells (p < 0.01). The survival of PC3 was also lower when irradiated by CDD than by HT or 7F but the difference was not as significant (p = 0.06 and 0.04, respectively). The higher survival fraction from HT delivery was unexpected because 90% of the 2 Gy was delivered in less than 1 min at a significantly higher dose rate than the other two delivery techniques. The results suggest that continuous dose delivery at a constant dose rate results in superior in vitro tumor cell killing compared with prolonged, segmented or variable dose rate delivery.

  16. Caffeine-enhanced survival of radiation-sensitive, repair-deficient Chinese hamster cells

    Utsumi, H.; Elkind, M.M.

    1983-01-01

    A clone of V79 Chinese hamster cells (V79-AL162/S-10) with unique properties has been isolated after a challenge of parental cells (V79-AL162) with 1 mM ouabain. Compared with parental cells, or with other clones isolated after the ouabain challenge, these cells form smaller colonies, are more sensitive to both x rays and fission-spectrum neutrons, and respond atypically to a postirradiation treatment with caffeine. Their enhanced response to x rays results mainly from a large reduction in the shoulder of their survival curve, probably because in late S phase, the most resistant phase in the cell cycle, the survival curve of these cells has a reduced shoulder width. Caffeine, and to a lesser extent theophylline, added to the colony-forming medium immediately after exposure appreciably increases the width of the shoulder of these sensitive cells, whereas caffeine has the opposite effect on the response of normal V79 cells. Thus the unique response of the V79-AL162/S-10 cells to a radiation posttreatment with caffeine (increased survival) results from a net increase in their ability to repair damage that is otherwise lethal; caffeine treatment ordinarly prevents normal V79 cells from repairing damage that is only potentially lethal

  17. Comparison of six different models describing survival of mammalian cells after irradiation

    Sontag, W.

    1990-01-01

    Six different cell-survival models have been compared. All models are based on the similar assumption that irradiated cells are able to exist in one of three states. S A is the state of a totally repaired cell, in state S C the cell contains lethal lesions and in state S b the cell contains potentially lethal lesions i.e. those which either can be repaired or converted into lethal lesions. The differences between the six models lie in the different mathematical relationships between the three states. To test the six models, six different sets of experimental data were used which describe cell survival at different repair times after irradiation with sparsely ionizing irradiation. In order to compare the models, a goodness-of-fit function was used. The differences between the six models were tested by use of the nonparametric Mann-Whitney two sample test. Based on the 95% confidence limit, this required separation into three groups. (orig.)

  18. Fasting protects mice from lethal DNA damage by promoting small intestinal epithelial stem cell survival.

    Tinkum, Kelsey L; Stemler, Kristina M; White, Lynn S; Loza, Andrew J; Jeter-Jones, Sabrina; Michalski, Basia M; Kuzmicki, Catherine; Pless, Robert; Stappenbeck, Thaddeus S; Piwnica-Worms, David; Piwnica-Worms, Helen

    2015-12-22

    Short-term fasting protects mice from lethal doses of chemotherapy through undetermined mechanisms. Herein, we demonstrate that fasting preserves small intestinal (SI) architecture by maintaining SI stem cell viability and SI barrier function following exposure to high-dose etoposide. Nearly all SI stem cells were lost in fed mice, whereas fasting promoted sufficient SI stem cell survival to preserve SI integrity after etoposide treatment. Lineage tracing demonstrated that multiple SI stem cell populations, marked by Lgr5, Bmi1, or HopX expression, contributed to fasting-induced survival. DNA repair and DNA damage response genes were elevated in SI stem/progenitor cells of fasted etoposide-treated mice, which importantly correlated with faster resolution of DNA double-strand breaks and less apoptosis. Thus, fasting preserved SI stem cell viability as well as SI architecture and barrier function suggesting that fasting may reduce host toxicity in patients undergoing dose intensive chemotherapy.

  19. Mathematical analysis of 51Cr-labelled red cell survival curves in congenital haemolytic anaemias

    Kasfiki, A.G.; Antipas, S.E.; Dimitriou, P.A.; Gritzali, F.A.; Melissinos, K.G.

    1982-01-01

    The parameters of 51 Cr labelled red cell survival curves were calculated in 26 patients with homozygous β-thalassaemia, 8 with sickle-cell anaemia and 3 with s-β-thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shorting of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s-β-thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors. (orig.)

  20. Role of DNA deletion length in mutation and cell survival

    Braby, L.A.; Morgan, T.L.

    1992-01-01

    A model is presented which is based on the assumption that malignant transformation, mutation, chromosome aberration, and reproductive death of cells are all manifestations of radiation induced deletions in the DNA of the cell, and that the size of the deletion in relation to the spacing of essential genes determines the consequences of that deletion. It is assumed that two independent types of potentially lethal lesions can result in DNA deletions, and that the relative numbers of these types of damage is dependent on radiation quality. The repair of the damage reduces the length of a deletion, but does not always eliminate it. The predictions of this model are in good agreement with a wide variety of experimental evidence. (author)

  1. STAT signaling in mammary gland differentiation, cell survival and tumorigenesis

    Haricharan, S; Li, Y

    2013-01-01

    The mammary gland is a unique organ that undergoes extensive and profound changes during puberty, menstruation, pregnancy, lactation and involution. The changes that take place during puberty involve large-scale proliferation and invasion of the fat-pad. During pregnancy and lactation, the mammary cells are exposed to signaling pathways that inhibit apoptosis, induce proliferation and invoke terminal differentiation. Finally, during involution the mammary gland is exposed to milk stasis, prog...

  2. Effect of single-dose radiation on cell survival and growth hormone secretion by rat anterior pituitary cells

    Hochberg, Z.; Kuten, A.; Hertz, P.; Tatcher, M.; Kedar, A.; Benderly, A.

    1983-01-01

    Cranial irradiation has been shown to impair growth hormone secretion in children. In this study a cell culture of dispersed rat anterior pituitary cells was exposed to single doses of radiation in the range of 100 to 1500 rad. Survival curves were obtained for the different anterior pituitary cell lines, and growth hormone secretion was measured in the tissue culture medium. Both survival and growth hormone secretion curves showed an initial shoulder in the range of 0 to 300 rad, followed by a decline between 300 to 750 rad. It is concluded that growth hormone secreting acidophilic pituicytes are sensitive to radiation at single doses greater than 300 rad

  3. A Consensus Genome-scale Reconstruction of Chinese Hamster Ovary Cell Metabolism

    Hefzi, Hooman; Ang, Kok  Siong; Hanscho, Michael; Bordbar, Aarash; Ruckerbauer, David; Lakshmanan, Meiyappan; Orellana, Camila  A.; Baycin-Hizal, Deniz; Huang, Yingxiang; Ley, Daniel; Martinez, Veronica  S.; Kyriakopoulos, Sarantos; Jimé nez, Natalia  E.; Zielinski, Daniel  C.; Quek, Lake-Ee; Wulff, Tune; Arnsdorf, Johnny; Li, Shangzhong; Lee, Jae  Seong; Paglia, Giuseppe; Loira, Nicolas; Spahn, Philipp  N.; Pedersen, Lasse  E.; Gutierrez, Jahir  M.; King, Zachary  A.; Lund, Anne  Mathilde; Nagarajan, Harish; Thomas, Alex; Abdel-Haleem, Alyaa M.; Zanghellini, Juergen; Kildegaard, Helene  F.; Voldborg, Bjø rn  G.; Gerdtzen, Ziomara  P.; Betenbaugh, Michael  J.; Palsson, Bernhard  O.; Andersen, Mikael  R.; Nielsen, Lars  K.; Borth, Nicole; Lee, Dong-Yup; Lewis, Nathan  E.

    2016-01-01

    Chinese hamster ovary (CHO) cells dominate biotherapeutic protein production and are widely used in mammalian cell line engineering research. To elucidate metabolic bottlenecks in protein production and to guide cell engineering and bioprocess

  4. Additive influence of extracellular pH, oxygen tension, and pressure on invasiveness and survival of human osteosarcoma cells

    Takao eMatsubara

    2013-07-01

    Full Text Available BACKGROUND/PURPOSE:The effects of chemical and physical interactions in the microenvironment of solid tumors have not been fully elucidated. We hypothesized that acidosis, hypoxia, and elevated interstitial fluid pressure (eIFP have additive effects on tumor cell biology and lead to more aggressive behavior during tumor progression. We investigated this phenomenon using 3 human osteosarcoma cell lines and a novel in vitro cell culture apparatus. MATERIALS AND METHODS:U2OS, SaOS, and MG63 cell lines were cultured in media adjusted to various pH levels, oxygen tension (hypoxia 2% O2, normoxia 20% O2, and hydrostatic gauge pressure (0 or 50 mm Hg. Growth rate, apoptosis, cell cycle parameters, and expression of mRNA for proteins associated with invasiveness and tumor microenvironment (CA IX, VEGF-A, HIF-1A, MMP-9, and TIMP-2 were analyzed. Levels of CA IX, HIF-1α, and MMP-9 were measured using immunofluorescence. The effect of pH on invasiveness was evaluated in a Matrigel chamber assay.RESULTS: Within the acidic–hypoxic–pressurized conditions that simulate the microenvironment at a tumor’s center, invasive genes were upregulated, but the cell cycle was downregulated. The combined influence of acidosis, hypoxia, and IFP promoted invasiveness and angiogenesis to a greater extent than did pH, pO2, or eIFP individually. Significant cell death after brief exposure to acidic conditions occurred in each cell line during acclimation to acidic media, while prolonged exposure to acidic media resulted in reduced cell death. Furthermore, 48-hour exposure to acidic conditions promoted tumor invasiveness in the Matrigel assay. CONCLUSION: Our findings demonstrate that tumor microenvironmental parameters—particularly pH, pO2, and eIFP—additively influence tumor proliferation, invasion, metabolism, and viability to enhance cell survival.

  5. A comparison of methods of determining the 100 percent survival of preserved red cells

    Valeri, C.R.; Pivacek, L.E.; Ouellet, R.; Gray, A.

    1984-01-01

    Studies were done to compare three methods to determine the 100 percent survival value from which to estimate the 24-hour posttransfusion survival of preserved red cells. The following methods using small aliquots of 51 Cr-labeled autologous preserved red cells were evaluated: First, the 125 I-albumin method, which is an indirect measurement of the recipient's red cell volume derived from the plasma volume measured using 125 I-labeled albumin and the total body hematocrit. Second, the body surface area method (BSA) in which the recipient's red cell volume is derived from a body surface area nomogram. Third, an extrapolation method, which extrapolates to zero time the radioactivity associated with the red cells in the recipient's circulation from 10 to 20 or 15 to 30 minutes after transfusion. The three methods gave similar results in all studies in which less than 20 percent of the transfused red cells were nonviable (24-hour posttransfusion survival values of between 80-100%), but not when more than 20 percent of the red cells were nonviable. When 21 to 35 percent of the transfused red cells were nonviable (24-hour posttransfusion survivals of 65 to 79%), values with the 125 I-albumin method and the body surface area method were about 5 percent lower (p less than 0.001) than values with the extrapolation method. When greater than 35 percent of the red cells were nonviable (24-hour posttransfusion survival values of less than 65%), values with the 125 I-albumin method and the body surface area method were about 10 percent lower (p less than 0.001) than those obtained by the extrapolation method

  6. Assessing the survival of MRC5 and a549 cell lines upon exposure to pyruvic Acid, sodium citrate and sodium bicarbonate - biomed 2013.

    Farah, Ibrahim O; Lewis, Veshell L; Ayensu, Wellington K; Cameron, Joseph A

    2013-01-01

    Lung cancer is among the most prevalent and deadly cancers in United States. In general, cancer cells are known to exhibit higher rates of glycolysis in comparison to normal cells. In attempting to exploit this unique cancer-dependent ATP generation phenomenon, it was our hypothesis that upon exposure to organic inhibitors of glycolysis, cancer cells would not survive normally and that their growth and viability would be vastly decreased; essential glycolytic ATP production will be exhausted to the point of collapsing energy utilization. Furthermore, we hypothesize that no negative effect would be seen with exposures to organic inhibitors for normal lung cells. The human lung fibroblast MRC-5 and the human A549 alveolar epithelial cell lines were used as in vitro models of normal lung and lung cancers respectively. Using standard methods, both cell lines were maintained and exposed to pyruvic acid, sodium citrate and sodium bicarbonate reagents at concentration levels ranging from 31.3-2,000 µg/ml in 96 well plates in quadruplets and experiments repeated at least three times using MTT, and cell counting (T4 Cellometer) assays as well as phase-contrast photo-imaging for parallel morphological displays of any changes in the course of their vitality and metabolic activities. Our results indicate that exposure of both cell lines to these organics resulted in concentration dependent cell destruction/cell survival depending on the cell line exposed. Pyruvic acid, sodium citrate and sodium bicarbonate showed statistically significant (pcancer biotherapeutics.

  7. Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells in irradiated bone marrow cell culture in vitro

    Fujitake, Hideki; Okamoto, Yuruko; Okubo, Hiroshi; Miyanomae, Takeshi; Kumagai, Keiko; Mori, K.J.

    1981-01-01

    Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells after irradiation were studied in the long-term culture of mouse bone marrow cells in vitro. No difference was observed in the survival of the stem cells among cultures in which 0 - 10 7 cells were re-inoculated on the adherent cell colonies in the culture flask. Stem cells showed a significant proliferation within 1 week and the number of the stem cells exceeded the control in 3 weeks after irradiation in the cultures with less than 10 6 re-inoculated cells per flask. In contrast, there was a considerable delay in the onset of stem cell proliferation after irradiation in the culture with 10 7 cells per flask. Based on these results, a possibility that a stimulator of stem cell proliferation, released from irradiated stromal cells, is cancelled by an inhibitory factor produced by irradiated or unirradiated haemopoietic cells is postulated. (author)

  8. Covariation of metabolic rates and cell size in coccolithophores

    Aloisi, G.

    2015-08-01

    Coccolithophores are sensitive recorders of environmental change. The size of their coccosphere varies in the ocean along gradients of environmental conditions and provides a key for understanding the fate of this important phytoplankton group in the future ocean. But interpreting field changes in coccosphere size in terms of laboratory observations is hard, mainly because the marine signal reflects the response of multiple morphotypes to changes in a combination of environmental variables. In this paper I examine the large corpus of published laboratory experiments with coccolithophores looking for relations between environmental conditions, metabolic rates and cell size (a proxy for coccosphere size). I show that growth, photosynthesis and, to a lesser extent, calcification covary with cell size when pCO2, irradiance, temperature, nitrate, phosphate and iron conditions change. With the exception of phosphate and temperature, a change from limiting to non-limiting conditions always results in an increase in cell size. An increase in phosphate or temperature (below the optimum temperature for growth) produces the opposite effect. The magnitude of the coccosphere-size changes observed in the laboratory is comparable to that observed in the ocean. If the biological reasons behind the environment-metabolism-size link are understood, it will be possible to use coccosphere-size changes in the modern ocean and in marine sediments to investigate the fate of coccolithophores in the future ocean. This reasoning can be extended to the size of coccoliths if, as recent experiments are starting to show, coccolith size reacts to environmental change proportionally to coccosphere size. The coccolithophore database is strongly biased in favour of experiments with the coccolithophore Emiliania huxleyi (E. huxleyi; 82 % of database entries), and more experiments with other species are needed to understand whether these observations can be extended to coccolithophores in general. I

  9. Metabolic Syndrome and Cardiovascular Risk Factors after Hematopoietic Cell Transplantation in Severe Mucopolysaccharidosis Type I (Hurler Syndrome).

    Braunlin, Elizabeth; Steinberger, Julia; DeFor, Todd; Orchard, Paul; Kelly, Aaron S

    2018-02-01

    Hematopoietic cell transplantation is a life-saving procedure, but one associated with increasing long-term cardiovascular risk requiring frequent long-term follow-up. This therapy has significantly lengthened survival in mucopolysaccharidosis type IH (Hurler syndrome), a disease with known coronary artery involvement. Metabolic syndrome-a constellation of central obesity, high blood pressure, low high-density lipoprotein cholesterol, elevated triglycerides, and fasting blood glucose-is associated with increased cardiovascular risk, and occurs when any 3 or more of these 5 components is present within a single individual. The incidence of metabolic syndrome and its components is poorly defined after transplantation for Hurler syndrome. Chart review of all long-term survivors of hematopoietic cell transplantation for Hurler syndrome ≥9 years of age for factors comprising the metabolic syndrome: obesity, high blood pressure, low high-density lipoprotein cholesterol, elevated triglycerides, and fasting blood glucose. Sixty-three patients were evaluated, 20 of whom had components of the metabolic syndrome available for review. There was no significant difference in age at transplantation, sex, number of transplants, pretransplant radiation, or percent engraftment between those with and without these data. Median follow-up after transplantation for the 20 patients with data was 14.3 years. Only 1 (5%) patient of this group fulfilled the criteria for metabolic syndrome. Fifty-three percent of the patients had 1 or more components of metabolic syndrome: the most common was high blood pressure occurring in 40%. Metabolic syndrome is uncommon in this cohort of long-term survivors of hematopoietic cell transplantation for Hurler syndrome but almost half of the patients had 1 or more components of the syndrome, with high blood pressure being the most common. Further studies are needed to develop guidelines in this diagnosis as well as other nonmalignant diseases of children

  10. Action of caffeine on the survival of x-irradiated cells

    Busse, P.M.

    1978-01-01

    Post-irradiation treatment of HeLa S3 cells with 1 mM caffeine results in a marked diminution of the surviving fraction as scored by colony formation. The decrease is dose-dependent; the effect of a 24-h post-irradiation treatment of a non-synchronous population with caffeine is to change the terminal slope of the survival curve and its intercept. Do is reduced from 130 to 60 rad; the extrapolation number is increased about twofold. The amount of post-irradiation killing is maximal if cells are exposed to caffeine at a concentration of at least 1 mM for 8 hours; less than 10% of unirradiated cells are killed under these conditions. Dose-response curves were also obtained for synchronous cells at various phases of the cell cycle. Similar results were obtained at all cell ages, but the magnitude of the effect is age-dependent. This age dependence was further explored in experiments in which mitotically collected cells were exposed to 300 or 500 rad doses at 2-hour intervals throughout the cell cycle. Treatment with caffeine for 24 hours after irradiation enhances the killing of cells late in the cycle more than in G 1 . The sensitivities of two other cell lines, CHO and EMT6, also were examined; both are substantially less sensitive to caffeine. The smaller cell-cycle dependence of CHO cells is qualitatively the same as that of HeLa cells

  11. Low-Dose Radiation Induces Genes Promoting Cell Survival

    Liu, Shu-Zheng; Chen, Dong; Mu, Ying

    1999-01-01

    Apoptosis is an important process controlling homeostasis of the body. It is influenced by stimuli constantly arising from the external and internal environment of the organism. It is well known that radiation could induce apoptosis of cells in vitro and in vivo. However, the dose-effect relationship of apoptosis extending to the low-dose range has scarcely been studied. Here, the molecular basis of the phenomenon is explored by examining the changes in expression of some of the proapoptotic and antiapoptotic genes

  12. The effect of egg versus seston quality on hatching success, naupliar metabolism and survival of Calanus finmarchicus in mesocosms dominated by Phaeocystis and diatoms

    Koski, Marja; Yebra, L.; Dutz, Jörg

    2012-01-01

    We studied the effect of a developing Skeletonema marinoi/Phaeocystis spp. bloom on Calanus finmarchicus hatching success, early naupliar survival and metabolism. Our focus was (1) on the development of reproductive rates during a bloom initiation, peak and decline in relation to the production o...

  13. [Thiamine and its derivatives in the regulation of cell metabolism].

    Tylicki, Adam; Siemieniuk, Magdalena

    2011-07-06

    For over 70 years thiamine (vitamin B1) has aroused the interest of biologists, biochemists and medical doctors because of its multilateral participation in key biochemical and physiological processes. The thiamine molecule is composed of pyrimidine and thiazole rings which are linked by a methylene bridge. It is synthesized by microorganisms, fungi and plants, whereas animals and humans have to obtain it from food. There are several known forms of vitamin B1 inside cells: free thiamine, three phosphate esters (mono-, di-, and triphosphate), and the recently found adenosine thiamine triphosphate. Thiamine has a dual, coenzymatic and non-coenzymatic role. First of all, it is a precursor of thiamin diphosphate, which is a coenzyme for over 20 characterized enzymes which are involved in cell bioenergetic processes leading to the synthesis of ATP. Moreover, these enzymes take part in the biosynthesis of pentose (required for the synthesis of nucleotides), amino acids and other organic compounds of cell metabolism. On the other hand, recent discoveries show the non-coenzymatic role of thiamine derivatives in the process of regulation of gene expression (riboswitches in microorganisms and plants), the stress response, and perhaps so far unknown signal transduction pathways associated with adverse environmental conditions, or transduction of nerve signals with participation of thiamine triphosphate and adenosine thiamine triphosphate. From the clinical point of view thiamine deficiency is related to beri-beri, Parkinson disease, Alzheimer disease, Wernicke-Korsakoff syndrome and other pathologies of the nervous system, and it is successfully applied in medical practice. On the other hand, identifying new synthetic analogues of thiamine which could be used as cytostatics, herbicides or agents preventing deficiency of vitamin B1 is currently the major goal of the research. In this paper we present the current state of knowledge of thiamine and its derivatives, indicating

  14. Survival of mouse testicular stem cells after γ or neutron irradiation

    Lu, C.C.; Meistrich, M.L.; Thames, H.D. Jr.

    1980-01-01

    The survival of mouse testicular stem cells after γ or neutron irradiation was measured by counts of repopulated tubular cross sections and by the numbers of differentiated spermatogenic cells produced. The numbers of such cells were determined either by sperm head counts of the X-isozyme of lactate dehydrogenase enzyme levels. Qualitatively similar results were obtained with all three assays. The results have confirmed that, with C3H mice, stem-cell survival is higher when the γ-radiation dose is fractionated by a 24-h interval. Single-dose γ-radiaton survival curves for the stem cell had large shoulders and also showed the presence of a radioresistant subpopulation which predominated after doses greater than 600 rad. Part of the shoulder must have resulted from repair of sublethal damage since neutron irradiation produced survival curves with smaller shoulders. The relative biological effectiveness for stem-cell killing for these neutrons (mean energy, 22 MeV) varied from about 2.9 at 10 rad of γ radiation to 2.2 at 600 rad

  15. Neurogenesis and Increase in Differentiated Neural Cell Survival via Phosphorylation of Akt1 after Fluoxetine Treatment of Stem Cells

    Anahita Rahmani

    2013-01-01

    Full Text Available Fluoxetine (FLX is a selective serotonin reuptake inhibitor (SSRI. Its action is possibly through an increase in neural cell survival. The mechanism of improved survival rate of neurons by FLX may relate to the overexpression of some kinases such as Akt protein. Akt1 (a serine/threonine kinase plays a key role in the modulation of cell proliferation and survival. Our study evaluated the effects of FLX on mesenchymal stem cell (MSC fate and Akt1 phosphorylation levels in MSCs. Evaluation tests included reverse transcriptase polymerase chain reaction, western blot, and immunocytochemistry assays. Nestin, MAP-2, and β-tubulin were detected after neurogenesis as neural markers. Ten μM of FLX upregulated phosphorylation of Akt1 protein in induced hEnSC significantly. Also FLX did increase viability of these MSCs. Continuous FLX treatment after neurogenesis elevated the survival rate of differentiated neural cells probably by enhanced induction of Akt1 phosphorylation. This study addresses a novel role of FLX in neurogenesis and differentiated neural cell survival that may contribute to explaining the therapeutic action of fluoxetine in regenerative pharmacology.

  16. The influence of printing parameters on cell survival rate and printability in microextrusion-based 3D cell printing technology.

    Zhao, Yu; Li, Yang; Mao, Shuangshuang; Sun, Wei; Yao, Rui

    2015-11-02

    Three-dimensional (3D) cell printing technology has provided a versatile methodology to fabricate cell-laden tissue-like constructs and in vitro tissue/pathological models for tissue engineering, drug testing and screening applications. However, it still remains a challenge to print bioinks with high viscoelasticity to achieve long-term stable structure and maintain high cell survival rate after printing at the same time. In this study, we systematically investigated the influence of 3D cell printing parameters, i.e. composition and concentration of bioink, holding temperature and holding time, on the printability and cell survival rate in microextrusion-based 3D cell printing technology. Rheological measurements were utilized to characterize the viscoelasticity of gelatin-based bioinks. Results demonstrated that the bioink viscoelasticity was increased when increasing the bioink concentration, increasing holding time and decreasing holding temperature below gelation temperature. The decline of cell survival rate after 3D cell printing process was observed when increasing the viscoelasticity of the gelatin-based bioinks. However, different process parameter combinations would result in the similar rheological characteristics and thus showed similar cell survival rate after 3D bioprinting process. On the other hand, bioink viscoelasticity should also reach a certain point to ensure good printability and shape fidelity. At last, we proposed a protocol for 3D bioprinting of temperature-sensitive gelatin-based hydrogel bioinks with both high cell survival rate and good printability. This research would be useful for biofabrication researchers to adjust the 3D bioprinting process parameters quickly and as a referable template for designing new bioinks.

  17. Metabolism

    ... Are More Common in People With Type 1 Diabetes Metabolic Syndrome Your Child's Weight Healthy Eating Endocrine System Blood Test: Basic Metabolic Panel (BMP) Activity: Endocrine System Growth Disorders Diabetes Center Thyroid Disorders Your Endocrine System Movie: Endocrine ...

  18. A CpG-methylation-based assay to predict survival in clear cell renal cell carcinoma

    Wei, Jin-Huan; Haddad, Ahmed; Wu, Kai-Jie; Zhao, Hong-Wei; Kapur, Payal; Zhang, Zhi-Ling; Zhao, Liang-Yun; Chen, Zhen-Hua; Zhou, Yun-Yun; Zhou, Jian-Cheng; Wang, Bin; Yu, Yan-Hong; Cai, Mu-Yan; Xie, Dan; Liao, Bing; Li, Cai-Xia; Li, Pei-Xing; Wang, Zong-Ren; Zhou, Fang-Jian; Shi, Lei; Liu, Qing-Zuo; Gao, Zhen-Li; He, Da-Lin; Chen, Wei; Hsieh, Jer-Tsong; Li, Quan-Zhen; Margulis, Vitaly; Luo, Jun-Hang

    2015-01-01

    Clear cell renal cell carcinomas (ccRCCs) display divergent clinical behaviours. Molecular markers might improve risk stratification of ccRCC. Here we use, based on genome-wide CpG methylation profiling, a LASSO model to develop a five-CpG-based assay for ccRCC prognosis that can be used with formalin-fixed paraffin-embedded specimens. The five-CpG-based classifier was validated in three independent sets from China, United States and the Cancer Genome Atlas data set. The classifier predicts the overall survival of ccRCC patients (hazard ratio=2.96−4.82; P=3.9 × 10−6−2.2 × 10−9), independent of standard clinical prognostic factors. The five-CpG-based classifier successfully categorizes patients into high-risk and low-risk groups, with significant differences of clinical outcome in respective clinical stages and individual ‘stage, size, grade and necrosis' scores. Moreover, methylation at the five CpGs correlates with expression of five genes: PITX1, FOXE3, TWF2, EHBP1L1 and RIN1. Our five-CpG-based classifier is a practical and reliable prognostic tool for ccRCC that can add prognostic value to the staging system. PMID:26515236

  19. The effect of vitamin E on cellular survival after X irradiation of lymphoma cells

    Fonck, K.; Kronings, A.W.T.

    1978-01-01

    Asynchronous cultures of a lymphocytic mouse leukaemic cell line L5178Y were X-irradiated under oxic and hypoxic conditions. The survival curves had almost no shoulder when the cells were grown under normal conditions and then irradiated in the presence of vitamin E, whereas a clear shoulder appeared when the cells were grown and irradiated in a medium supplemented with vitamin E (100 μg/ml). There was no change in the final sensitivity to lethal events in the vitamin E enriched cells. The results suggest that the radioprotective effect of vitamin E depends on its incorporation into the cell membranes. (U.K.)

  20. Dose-rate effects on the cell cycle and survival of S3 HeLa and V79 cells

    Mitchell, J.B.; Bedford, J.S.; Bailey, S.M.

    1979-01-01

    The effects of continuous irradiation at different dose rates on the cell cycle and on cell survival were studied using synchronized S3 HeLa and V79 cells. The minimum dose rate necessary to stop cell division was found to be approximately 23 rad/hr for HeLa cells and 270 rad/hr for V79 cells. For dose rates that stop cell division, cells progress through G 1 and S, with a small delay in the S phase, and are blocked in G 2 . Appreciable mitotic accumulation was observed for HeLa cells at dose rates which stopped cell division. By comparison, much less mitotic accumulation was observed for V79 cells over a range of dose rates from 37 to 270 rad/hr. Minimum mitotic delays for a variety of dose rates were determined for both cell lines. S3 HeLa cells are much more sensitive in this respect than V79 cells; however, it appeared that for higher dose rates the minimum mitotic delay in HeLa cells asymptotically approached a value of about 35 hr. In addition to the qualitative differences observed for the two cell lines in regard to mitotic accumulation, HeLa cells accumulated for prolonged periods in the presence of colcemid while V79 cells were blocked for only a few hours, HeLa cells show a dramatic effect of redistribution of cells into sensitive phases of the cell cycle during exposure, which was reflected in the survival curves at low dose rate. More cell killing per unit dose was observed at 37 than at 74 rad/hr

  1. A new scoring system for predicting survival in patients with non-small cell lung cancer

    Schild, Steven E; Tan, Angelina D; Wampfler, Jason A; Ross, Helen J; Yang, Ping; Sloan, Jeff A

    2015-01-01

    This analysis was performed to create a scoring system to estimate the survival of patients with non-small cell lung cancer (NSCLC). Data from 1274 NSCLC patients were analyzed to create and validate a scoring system. Univariate (UV) and multivariate (MV) Cox models were used to evaluate the prognostic importance of each baseline factor. Prognostic factors that were significant on both UV and MV analyses were used to develop the score. These included quality of life, age, performance status, primary tumor diameter, nodal status, distant metastases, and smoking cessation. The score for each factor was determined by dividing the 5-year survival rate (%) by 10 and summing these scores to form a total score. MV models and the score were validated using bootstrapping with 1000 iterations from the original samples. The score for each prognostic factor ranged from 1 to 7 points with higher scores reflective of better survival. Total scores (sum of the scores from each independent prognostic factor) of 32–37 correlated with a 5-year survival of 8.3% (95% CI = 0–17.1%), 38–43 correlated with a 5-year survival of 20% (95% CI = 13–27%), 44–47 correlated with a 5-year survival of 48.3% (95% CI = 41.5–55.2%), 48–49 correlated to a 5-year survival of 72.1% (95% CI = 65.6–78.6%), and 50–52 correlated to a 5-year survival of 84.7% (95% CI = 79.6–89.8%). The bootstrap method confirmed the reliability of the score. Prognostic factors significantly associated with survival on both UV and MV analyses were used to construct a valid scoring system that can be used to predict survival of NSCLC patients. Optimally, this score could be used when counseling patients, and designing future trials

  2. Squamous cell carcinoma of the breast in the United States: incidence, demographics, tumor characteristics, and survival.

    Yadav, Siddhartha; Yadav, Dhiraj; Zakalik, Dana

    2017-07-01

    Squamous cell carcinoma of breast accounts for less than 0.1% of all breast cancers. The purpose of this study is to describe the epidemiology and survival of this rare malignancy. Data were extracted from the National Cancer Institute's Surveillance, Epidemiology and End Results Registry to identify women diagnosed with squamous cell carcinoma of breast between 1998 and 2013. SEER*Stat 8.3.1 was used to calculate age-adjusted incidence, age-wise distribution, and annual percentage change in incidence. Kaplan-Meier curves were plotted for survival analysis. Univariate and multivariate Cox proportional hazard regression model was used to determine predictors of survival. A total of 445 cases of squamous cell carcinoma of breast were diagnosed during the study period. The median age of diagnosis was 67 years. The overall age-adjusted incidence between 1998 and 2013 was 0.62 per 1,000,000 per year, and the incidence has been on a decline. Approximately half of the tumors were poorly differentiated. Stage II was the most common stage at presentation. Majority of the cases were negative for expression of estrogen and progesterone receptor. One-third of the cases underwent breast conservation surgery while more than half of the cases underwent mastectomy (unilateral or bilateral). Approximately one-third of cases received radiation treatment. The 1-year and 5-year cause-specific survival was 81.6 and 63.5%, respectively. Excluding patient with metastasis or unknown stage at presentation, in multivariate Cox proportional hazard model, older age at diagnosis and higher tumor stage (T3 or T4) or nodal stage at presentation were significant predictors of poor survival. Our study describes the unique characteristics of squamous cell carcinoma of breast and demonstrates that it is an aggressive tumor with a poor survival. Older age and higher tumor or nodal stages at presentation were independent predictors of poor survival for loco-regional stages.

  3. Bone-Marrow Stem-Cell Survival in the Non-Uniformly Exposed Mammal

    Bond, V. P.; Robinson, C. V. [Brookhaven National Laboratory, Medical Research Center, Upton, Long Island, NY (United States)

    1967-07-15

    For comparison of the effectiveness of non-uniform versus uniform irradiations in causing haematological death in mammals, a model of the irradiated haemopoietic system has been proposed. The essential features of this model are: (1) that different parts of the haemopoietic system have numbers of stem cells which are proportioned to the amounts of active marrow in those parts as measured by {sup 59}Fe uptake, (2) that stem cells in the different parts are subject to the, same dose-survival relationship, and (3) that survival of the animal depends on survival of a critical fraction of the total number of stem cells independent of their distribution among the parts of the total marrow mass. To apply this model one needs to know: (a) the relative {sup 59}Fe uptakes of the different parts of the haemopoietic system, (b) the doses delivered to those parts by each of the exposures to be compared, and (c) the dose-survival curve applicable to the stem cells. From these one can calculate the fraction of stem cells surviving each exposure. In a preliminary communication the applicability of the model was investigated using data obtained entirely from the literature. Additional data, particularly on bone-marrow distribution, have since been obtained and are included here. The primary object of the present paper is to test further the validity of the above 'stem-cell survival model'. Data on bilateral (essentially uniform) versus unilateral and non-uniform rotational exposures in mammals are examined with respect to the surviving fraction of stem cells at the LD{sub 50/30} day dose level. Although an adequate test is not possible at present for lack of a full set of data in any one species, a partial test indicates compatibility with data for dogs and rats. Other possible mortality determinants such as doses or exposures at entrance, midline or exit, or the gram-rads or average dose to the marrow, appear to be less useful than the critical stem-cell survival fraction.

  4. Suspension Matrices for Improved Schwann-Cell Survival after Implantation into the Injured Rat Spinal Cord

    Patel, Vivek; Joseph, Gravil; Patel, Amit; Patel, Samik; Bustin, Devin; Mawson, David; Tuesta, Luis M.; Puentes, Rocio; Ghosh, Mousumi

    2010-01-01

    Abstract Trauma to the spinal cord produces endogenously irreversible tissue and functional loss, requiring the application of therapeutic approaches to achieve meaningful restoration. Cellular strategies, in particular Schwann-cell implantation, have shown promise in overcoming many of the obstacles facing successful repair of the injured spinal cord. Here, we show that the implantation of Schwann cells as cell suspensions with in-situ gelling laminin:collagen matrices after spinal-cord contusion significantly enhances long-term cell survival but not proliferation, as well as improves graft vascularization and the degree of axonal in-growth over the standard implantation vehicle, minimal media. The use of a matrix to suspend cells prior to implantation should be an important consideration for achieving improved survival and effectiveness of cellular therapies for future clinical application. PMID:20144012

  5. Methanogenic H2 syntrophy among thermophiles: a model of metabolism, adaptation and survival in the subsurface

    Topcuoglu, B. D.; Stewart, L. C.; Butterfield, D. A.; Huber, J. A.; Holden, J. F.

    2016-12-01

    Approximately 1 giga ton (Gt, 1015 g) of CH4 is formed globally per year from H2, CO2 and acetate through methanogenesis, largely by methanogens growing in syntrophic association with anaerobic microbes that hydrolyze and ferment biopolymers. However, our understanding of methanogenesis in hydrothermal regions of the subseafloor and potential syntrophic methanogenesis at thermophilic temperatures (i.e., >50°C) is nascent. In this study, the growth of natural assemblages of thermophilic methanogens from Axial Seamount was primarily limited by H2 availability. Heterotrophs supported thermophilic methanogenesis by H2 syntrophy in microcosm incubations of hydrothermal fluids at 55°C and 80°C supplemented with tryptone only. Based on 16S rRNA gene sequencing, only heterotrophic archaea that produce H2, H2-consuming methanogens, and sulfate reducing archaea were found in 80°C tryptone microcosms from Marker 113 vent. No bacteria were found. In 55°C tryptone microcosms, sequences were found from H2-producing bacteria and H2-consuming methanogens and sulfate-reducing bacteria. In order to model the impact of H2 syntrophy at hyperthemophilic temperatures, a co-culture was established consisting of the H2-producing hyperthermophilic heterotroph Thermococcus paralvinellae and a H2-consuming hyperthermophilic methanogen Methanocaldococcus bathoardescens. When grown alone in a chemostat, the growth rates and steady-state cell concentrations of T. paralvinellae decreased significantly when a high H2 (70 µM) background was present. H2 inhibition was ameliorated by the production of formate, but in silico modeling suggests less energetic yield for the cells. H2 syntrophy relieved H2 inhibition for both the heterotroph and the methanogenic partners. The results demonstrate that thermophilic H2 syntrophy can support methanogenesis within natural microbial assemblages and may be an important alternative energy source for thermophilic autotrophs in marine geothermal environments.

  6. Par3L enhances colorectal cancer cell survival by inhibiting Lkb1/AMPK signaling pathway

    Li, Taiyuan; Liu, Dongning; Lei, Xiong; Jiang, Qunguang

    2017-01-01

    Partitioning defective 3-like protein (Par3L) is a recently identified cell polarity protein that plays an important role in mammary stem cell maintenance. Previously, we showed that high expression of Par3L is associated with poor survival in malignant colorectal cancer (CRC), but the underlying mechanism remained unknown. To this end, we established a Par3L knockout colorectal cancer cell line using the CRISPR/Cas system. Interestingly, reduced proliferation, enhanced cell death and caspase-3 activation were observed in Par3L knockout (KO) cells as compared with wildtype (WT) cells. Consistent with previous studies, we showed that Par3L interacts with a tumor suppressor protein liver kinase B1 (Lkb1). Moreover, Par3L depletion resulted in abnormal activation of Lkb1/AMPK signaling cascade. Knockdown of Lkb1 in these cells could significantly reduce AMPK activity and partially rescue cell death caused by Par3L knockdown. Furthermore, we showed that Par3L KO cells were more sensitive to chemotherapies and irradiation. Together, these results suggest that Par3L is essential for colorectal cancer cell survival by inhibiting Lkb1/AMPK signaling pathway, and is a putative therapeutic target for CRC. - Highlights: • Par3L knockout using the CRISPR/Cas system induces apoptosis in colorectal cancer cells. • Par3L interacts with Lkb1 and regulates the activity of AMPK signaling cascade. • Par3L knockout cells are more sensitive to treatment of different chemotherapy drugs and irradiation.

  7. Survival and mortality among users and non-users of hydroxyurea with sickle cell disease.

    de Araujo, Olinda Maria Rodrigues; Ivo, Maria Lúcia; Ferreira Júnior, Marcos Antonio; Pontes, Elenir Rose Jardim Cury; Bispo, Ieda Maria Gonçalves Pacce; de Oliveira, Eveny Cristine Luna

    2015-01-01

    to estimate survival, mortality and cause of death among users or not of hydroxyurea with sickle cell disease. cohort study with retrospective data collection, from 1980 to 2010 of patients receiving inpatient treatment in two Brazilian public hospitals. The survival probability was determined using the Kaplan-Meier estimator, survival calculations (SPSS version 10.0), comparison between survival curves, using the log rank method. The level of significance was p=0.05. of 63 patients, 87% had sickle cell anemia, with 39 using hydroxyurea, with a mean time of use of the drug of 20.0±10.0 years and a mean dose of 17.37±5.4 to 20.94±7.2 mg/kg/day, raising the fetal hemoglobin. In the comparison between those using hydroxyurea and those not, the survival curve was greater among the users (p=0.014). A total of 10 deaths occurred, with a mean age of 28.1 years old, and with Acute Respiratory Failure as the main cause. the survival curve is greater among the users of hydroxyurea. The results indicate the importance of the nurse incorporating therapeutic advances of hydroxyurea in her care actions.

  8. A Hyaluronan-Based Injectable Hydrogel Improves the Survival and Integration of Stem Cell Progeny following Transplantation

    Brian G. Ballios

    2015-06-01

    Full Text Available The utility of stem cells and their progeny in adult transplantation models has been limited by poor survival and integration. We designed an injectable and bioresorbable hydrogel blend of hyaluronan and methylcellulose (HAMC and tested it with two cell types in two animal models, thereby gaining an understanding of its general applicability for enhanced cell distribution, survival, integration, and functional repair relative to conventional cell delivery in saline. HAMC improves cell survival and integration of retinal stem cell (RSC-derived rods in the retina. The pro-survival mechanism of HAMC is ascribed to the interaction of the CD44 receptor with HA. Transient disruption of the retinal outer limiting membrane, combined with HAMC delivery, results in significantly improved rod survival and visual function. HAMC also improves the distribution, viability, and functional repair of neural stem and progenitor cells (NSCs. The HAMC delivery system improves cell transplantation efficacy in two CNS models, suggesting broad applicability.

  9. Metabolic basis of ethanol-induced cytotoxicity in recombinant HepG2 cells: Role of nonoxidative metabolism

    Wu Hai; Cai Ping; Clemens, Dahn L.; Jerrells, Thomas R.; Ansari, G.A. Shakeel; Kaphalia, Bhupendra S.

    2006-01-01

    Chronic alcohol abuse, a major health problem, causes liver and pancreatic diseases and is known to impair hepatic alcohol dehydrogenase (ADH). Hepatic ADH-catalyzed oxidation of ethanol is a major pathway for the ethanol disposition in the body. Hepatic microsomal cytochrome P450 (CYP2E1), induced in chronic alcohol abuse, is also reported to oxidize ethanol. However, impaired hepatic ADH activity in a rat model is known to facilitate a nonoxidative metabolism resulting in formation of nonoxidative metabolites of ethanol such as fatty acid ethyl esters (FAEEs) via a nonoxidative pathway catalyzed by FAEE synthase. Therefore, the metabolic basis of ethanol-induced cytotoxicity was determined in HepG2 cells and recombinant HepG2 cells transfected with ADH (VA-13), CYP2E1 (E47) or ADH + CYP2E1 (VL-17A). Western blot analysis shows ADH deficiency in HepG2 and E47 cells, compared to ADH-overexpressed VA-13 and VL-17A cells. Attached HepG2 cells and the recombinant cells were incubated with ethanol, and nonoxidative metabolism of ethanol was determined by measuring the formation of FAEEs. Significantly higher levels of FAEEs were synthesized in HepG2 and E47 cells than in VA-13 and VL-17A cells at all concentrations of ethanol (100-800 mg%) incubated for 6 h (optimal time for the synthesis of FAEEs) in cell culture. These results suggest that ADH-catalyzed oxidative metabolism of ethanol is the major mechanism of its disposition, regardless of CYP2E1 overexpression. On the other hand, diminished ADH activity facilitates nonoxidative metabolism of ethanol to FAEEs as found in E47 cells, regardless of CYP2E1 overexpression. Therefore, CYP2E1-mediated oxidation of ethanol could be a minor mechanism of ethanol disposition. Further studies conducted only in HepG2 and VA-13 cells showed lower ethanol disposition and ATP concentration and higher accumulation of neutral lipids and cytotoxicity (apoptosis) in HepG2 cells than in VA-13 cells. The apoptosis observed in HepG2 vs

  10. Metabolic cooperativity between epithelial cells and adipocytes of mice

    Bartley, J.C.; Emerman, J.T.; Bissell, M.J.

    1981-01-01

    We have demonstrated that glycogen and lipid synthesis in adipocytes is modulated by the lactational state and that this modulation in mammary adipocytes requires the presence of the adjacent epithelial cells. Glycogen and lipid synthesis from [ 14 C]glucose was measured in mammary fat pads cleared of epithelium, in abdominal fat pads, and in adipocytes from both sources and from intact mammary gland of mature virgin, pregnant, and lactating mice. Accumulation of glycogen, the activity of glycogen synthase, and the lipogenic rate in abdominal and mammary adipocytes remained high during pregnancy but decreased to insignificant levels by early lactation. The depressant effects of lactation were observed solely in those mammary adipocytes isolated from intact glands. The presence of mammary epithelial cells was also required to effect the stimulated lipogenesis in mammary adipocytes during pregnancy. We conclude that the metabolic activity of adipocytes is modulated both during pregnancy and lactation to channel nutrients to the mammary epithelial cell. The fact that the changes occur in mammary adipocytes only when epithelial cells are present indicates that local as well as systemic factors are operating in these modulations

  11. EGFR overexpressing cells and tumors are dependent on autophagy for growth and survival

    Jutten, Barry; Keulers, Tom G.; Schaaf, Marco B.E.; Savelkouls, Kim; Theys, Jan; Span, Paul N.; Vooijs, Marc A.; Bussink, Johan; Rouschop, Kasper M.A.

    2013-01-01

    Background and purpose: The epidermal growth factor receptor (EGFR) is overexpressed, amplified or mutated in various human epithelial tumors, and is associated with tumor aggressiveness and therapy resistance. Autophagy activation provides a survival advantage for cells in the tumor microenvironment. In the current study, we assessed the potential of autophagy inhibition (using chloroquine (CQ)) in treatment of EGFR expressing tumors. Material and methods: Quantitative PCR, immunohistochemistry, clonogenic survival, proliferation assays and in vivo tumor growth were used to assess this potential. Results: We show that EGFR overexpressing xenografts are sensitive to CQ treatment and are sensitized to irradiation by autophagy inhibition. In HNSSC xenografts, a correlation between EGFR and expression of the autophagy marker LC3b is observed, suggesting a role for autophagy in EGFR expressing tumors. This observation was substantiated in cell lines, showing high EGFR expressing cells to be more sensitive to CQ addition as reflected by decreased proliferation and survival. Surprisingly high EGFR expressing cells display a lower autophagic flux. Conclusions: The EGFR high expressing cells and tumors investigated in this study are highly dependent on autophagy for growth and survival. Inhibition of autophagy may therefore provide a novel treatment opportunity for EGFR overexpressing tumors

  12. Influence of preirradiational and postirradiational heating of lyophilized Micrococcus radioproteolyticus cells on their survival

    Ryznar, L; Drasil, V [Ceskoslovenska Akademie Ved, Brno. Biofysikalni Ustav

    1981-12-10

    The survival curve of Micrococcus radioproteolyticus following gamma irradiation of lyophilized cells is characterized by a broad shoulder reaching as far as the dose range 10 - 20 kGy (1 - 2 Mrad). The course of the curve indicates that under these conditions most of the changes induced by irradiation have the character of sublethal damage, which the cell can repair. The course of the survival curve does not change if the lyophilized cells are heated prior to irradiation for 2 h at 60 /sup 0/C. Certain changes do occur if the preirradiational temperature is 80 /sup 0/C. If the cells are exposed to increased temperature after irradiation even a temperature of 60 /sup 0/C brings about a marked decrease in survival. A temperature of 80 /sup 0/C after irradiation leads to extensive changes in the shape of survival curves, which are characterized by a narrowing or even disappearing of the shoulders. It can be concluded from the results obtained that an increased temperature modifies the capability of irradiated lyophilized cells to repair radiation damage.

  13. Influence of preirradiational and postirradiational heating of lyophilized Micrococcus radioproteolyticus cells on their survival

    Ryznar, L.; Drasil, V.

    1981-01-01

    The survival curve of Micrococcus radioproteolyticus following gamma irradiation of lyophilized cells is characterized by a broad shoulder reaching as far as the dose range 10 - 20 kGy (1 - 2 Mrad). The course of the curve indicates that under these conditions most of the changes induced by irradiation have the character of sublethal damage, which the cell can repair. The course of the survival curve does not change if the lyophilized cells are heated prior to irradiation for 2 h at 60 0 C. Certain changes do occur if the preirradiational temperature is 80 0 C. If the cells are exposed to increased temperature after irradiation even a temperature of 60 0 C brings about a marked decrease in survival. A temperature of 80 0 C after irradiation leads to extensive changes in the shape of survival curves, which are characterized by a narrowing or even disappearing of the shoulders. It can be concluded from the results obtained that an increased temperature modifies the capability of irradiated lyophilized cells to repair radiation damage. (author)

  14. Club cells surviving influenza A virus infection induce temporary nonspecific antiviral immunity.

    Hamilton, Jennifer R; Sachs, David; Lim, Jean K; Langlois, Ryan A; Palese, Peter; Heaton, Nicholas S

    2016-04-05

    A brief window of antigen-nonspecific protection has been observed after influenza A virus (IAV) infection. Although this temporary immunity has been assumed to be the result of residual nonspecific inflammation, this period of induced immunity has not been fully studied. Because IAV has long been characterized as a cytopathic virus (based on its ability to rapidly lyse most cell types in culture), it has been a forgone conclusion that directly infected cells could not be contributing to this effect. Using a Cre recombinase-expressing IAV, we have previously shown that club cells can survive direct viral infection. We show here not only that these cells can eliminate all traces of the virus and survive but also that they acquire a heightened antiviral response phenotype after surviving. Moreover, we experimentally demonstrate temporary nonspecific viral immunity after IAV infection and show that surviving cells are required for this phenotype. This work characterizes a virally induced modulation of the innate immune response that may represent a new mechanism to prevent viral diseases.

  15. TNF-α promotes cell survival through stimulation of K+ channel and NFκB activity in corneal epithelial cells

    Wang Ling; Reinach, Peter; Lu, Luo

    2005-01-01

    Tumor necrosis factor (TNF-α) in various cell types induces either cell death or mitogenesis through different signaling pathways. In the present study, we determined in human corneal epithelial cells how TNF-α also promotes cell survival. Human corneal epithelial (HCE) cells were cultured in DMEM/F-12 medium containing 10% FBS. TNF-α stimulation induced activation of a voltage-gated K + channel detected by measuring single channel activity using patch clamp techniques. The effect of TNF-α on downstream events included NFκB nuclear translocation and increases in DNA binding activities, but did not elicit ERK, JNK, or p38 limb signaling activation. TNF-α induced increases in p21 expression resulting in partial cell cycle attenuation in the G 1 phase. Cell cycle progression was also mapped by flow cytometer analysis. Blockade of TNF-α-induced K + channel activity effectively prevented NFκB nuclear translocation and binding to DNA, diminishing the cell-survival protective effect of TNF-α. In conclusion, TNF-α promotes survival of HCE cells through sequential stimulation of K + channel and NFκB activities. This response to TNF-α is dependent on stimulating K + channel activity because following suppression of K + channel activity TNF-α failed to activate NFκB nuclear translocation and binding to nuclear DNA

  16. Microbubble-based enhancement of radiation effect: Role of cell membrane ceramide metabolism.

    Azza Al-Mahrouki

    Full Text Available Ultrasound (US stimulated microbubbles (MB is a new treatment approach that sensitizes cancer cells to radiation (XRT. The molecular pathways in this response remain unelucidated, however, previous data has supported a role for cell membrane-metabolism related pathways including an up regulation of UDP glycosyltransferase 8 (UGT8, which catalyzes the transfer of galactose to ceramide, a lipid that is associated with the induction of apoptotic signalling. In this study, the role of UGT8 in responses of prostate tumours to ultrasound-stimulated microbubble radiation enhancement therapy is investigated. Experiments were carried out with cells in vitro and tumours in vivo in which UGT8 levels had been up regulated or down regulated. Genetically modified PC3 cells were treated with XRT, US+MB, or a combination of XRT+US+MB. An increase in the immunolabelling of ceramide was observed in cells where UGT8 was down-regulated as opposed to cells where UGT8 was either not regulated or was up-regulated. Clonogenic assays have revealed a decreased level of cellular survival with the down-regulation of UGT8. Xenograft tumours generated from stably transfected PC3 cells were also treated with US+MB, XRT or US+MB+XRT. Histology demonstrated more cellular damage in tumours with down-regulated UGT8 in comparison with control tumours. In contrast, tumours with up-regulated UGT8 had less damage than control tumours. Power Doppler imaging indicated a reduction in the vascular index with UGT8 down-regulation and photoacoustic imaging revealed a reduction in oxygen saturation. This was contrary to when UGT8 was up regulated. The down regulation of UGT8 led to the accumulation of ceramide resulting in more cell death signalling and therefore, a greater enhancement of radiation effect when vascular disruption takes place through the use of ultrasound-stimulated microbubbles.

  17. Survival outcomes for oligometastasis in resected non-small cell lung cancer.

    Shimada, Yoshihisa; Saji, Hisashi; Kakihana, Masatoshi; Kajiwara, Naohiro; Ohira, Tatsuo; Ikeda, Norihiko

    2015-10-01

    We investigated the factors associated with post-recurrence survival and the treatment for non-small-cell lung cancer patients with postoperative distant recurrence, especially oligometastasis. We reviewed the data of 272 patients with distant recurrence who underwent resection of non-small-cell lung cancer from January 2000 through December 2011. The type of distant recurrence was classified as oligometastasis (n = 76, 28%) or polymetastasis (n = 196, 72%). Forty-seven (62%) patients with oligometastasis received local therapy (surgery 5, radiotherapy 9, sequential local and systemic therapy 28, chemoradiotherapy 5). Multivariate analysis revealed older age, non-adenocarcinoma, shorter disease-free interval, no pulmonary metastasis, liver metastases, bone metastases, and polymetastasis had significant associations with unfavorable post-recurrence survival. Subgroup analysis of patients with oligometastasis showed histology and disease-free interval had a great impact on survival. Smoking history and histology were associated with survival in patients with lung oligometastasis, whereas systemic treatment and longer disease-free interval were related to increased post-recurrence survival in those with brain oligometastasis. This study showed that an oligometastatic state per se was a significant favorable factor. Optimization of personalized systemic treatment and adding local treatment are important in the management of patients with non-small-cell lung cancer and oligometastasis. © The Author(s) 2015.

  18. The effect of caffeine and adenine on radiation induced suppression of DNA synthesis, and cell survival

    Wilcoxson, L.T.; Griffiths, T.D.

    1984-01-01

    Exposure of cultured mammalian cells to ionizing radiation or UV light results in a transient decrease in the rate of DNA synthesis. This depression in synthetic rate may be attenuated or deferred via a post-irradiation treatment with caffeine or adenine. It has been suggested that this attenuation may increase the fixation of damage and, therefore, increase radiation sensitivity. However, it has been previously reported that, for V79 cells treated with caffeine or adenine, no correlation exists between the extent of depression and cell survival. The present investigation expands upon these findings by examining the effect of caffeine or adenine post-irradiation treatment on two cell lines with normal UV sensitivity, mouse 3T3 and CHO AA8 cells, and one UV sensitive cell line, CHO UV5 cells. Both caffeine and adenine have been found to reduce, or delay, the suppression in DNA synthesis in all three cell lines. Surprisingly, caffeine appeared to induced even the UV5 cells to recover DNA synthetic ability. The amount of reduction in suppression of DNA synthesis, however, varies between the different cell lines and no consistent relationship with cell survival has emerged

  19. Astrocytes protect glioma cells from chemotherapy and upregulate survival genes via gap junctional communication.

    Lin, Qingtang; Liu, Zhao; Ling, Feng; Xu, Geng

    2016-02-01

    Gliomas are the most common type of primary brain tumor. Using current standard treatment regimens, the prognosis of patients with gliomas remains poor, which is predominantly due to the resistance of glioma cells to chemotherapy. The organ microenvironment has been implicated in the pathogenesis and survival of tumor cells. Thus, the aim of the present study was to test the hypothesis that astrocytes (the housekeeping cells of the brain microenvironment) may protect glioma cells from chemotherapy and to investigate the underlying mechanism. Immunofluorescent and scanning electron microscopy demonstrated that glioma cells were surrounded and infiltrated by activated astrocytes. In vitro co-culture of glioma cells with astrocytes significantly reduced the cytotoxic effects on glioma cells caused by various chemotherapeutic agents, as demonstrated by fluorescein isothiocyanate-propidium iodide flow cytometry. Transwell experiments indicated that this protective effect was dependent on physical contact and the gap junctional communication (GJC) between astrocytes and glioma cells. Microarray expression profiling further revealed that astrocytes upregulated the expression levels of various critical survival genes in the glioma cells via GJC. The results of the present study indicated that the organ microenvironment may affect the biological behavior of tumor cells and suggest a novel mechanism of resistance in glioma cells, which may be of therapeutic relevance clinically.

  20. Sustainability of keratinocyte gene transfer and cell survival in vivo.

    Choate, K A; Khavari, P A

    1997-05-20

    The epidermis is an attractive site for therapeutic gene delivery because it is accessible and capable of delivering polypeptides to the systemic circulation. A number of difficulties, however, have emerged in attempts at cutaneous gene delivery, and central among these is an inability to sustain therapeutic gene production. We have examined two major potential contributing factors, viral vector stamina and involvement of long-lived epidermal progenitor cells. Human keratinocytes were either untreated or transduced with a retroviral vector for beta-galactosidase (beta-Gal) at > 99% efficiency and then grafted onto immunodeficient mice to regenerate human epidermis. Human epidermis was monitored in vivo after grafting for clinical and histologic appearance as well as for gene expression. Although integrated vector sequences persisted unchanged in engineered epidermis at 10 weeks post-grafting, retroviral long terminal repeat (LTR)-driven beta-Gal expression ceased in vivo after approximately 4 weeks. Endogenous cellular promoters, however, maintained consistently normal gene expression levels without evidence of time-dependent decline, as determined by immunostaining with species-specific antibodies for human involucrin, filaggrin, keratinocyte transglutaminase, keratin 10, type VII collagen, and Laminin 5 proteins out to week 14 post-grafting. Transduced human keratinocytes generated multilayer epidermis sustained through multiple epidermal turnover cycles; this epidermis demonstrated retention of a spatially appropriate pattern of basal and suprabasal epidermal marker gene expression. These results confirm previous findings suggesting that viral promoter-driven gene expression is not durable and demonstrate that keratinocytes passaged in vitro can regenerate and sustain normal epidermis for prolonged periods.

  1. A preliminary study on action mechanisms of surviving expression in cell apoptosis induced by high-LET radiation

    Jin Xiaodong; Li Qiang; Gong Li; Wu Qingfeng; Li Ping; Dai Zhongying; Liu Xinguo; Tao Jiajun

    2010-01-01

    It has been proven that over-expression of surviving in cancerous cell lines is related to the radioresistance of cells to high-LET radiation in previous work. In this study, action mechanisms of surviving gene in apoptosis induced by high-LET radiation were investigated. We found that inhibiting surviving by siRNA had no notable influence on Bcl-2 and Bax expressions induced by carbon ions. Surviving depressed cell apoptosis through the inhibition of the activities of caspase-3 and -9 possibly in cell apoptosis induced by high-LET radiation. (authors)

  2. Transplantation of Gene-Edited Hepatocyte-like Cells Modestly Improves Survival of Arginase-1-Deficient Mice

    Yuan Yan Sin

    2018-03-01

    Full Text Available Progress in gene editing research has been accelerated by utilizing engineered nucleases in combination with induced pluripotent stem cell (iPSC technology. Here, we report transcription activator-like effector nuclease (TALEN-mediated reincorporation of Arg1 exons 7 and 8 in iPSCs derived from arginase-1-deficient mice possessing Arg1Δ alleles lacking these terminal exons. The edited cells could be induced to differentiate into hepatocyte-like cells (iHLCs in vitro and were subsequently used for transplantation into our previously described (Sin et al., PLoS ONE 2013 tamoxifen-inducible Arg1-Cre arginase-1-deficient mouse model. While successful gene-targeted repair was achieved in iPSCs containing Arg1Δ alleles, only minimal restoration of urea cycle function could be observed in the iHLC-transplanted mice compared to control mice, and survival in this lethal model was extended by up to a week in some mice. The partially rescued phenotype may be due to inadequate regenerative capacity of arginase-1-expressing cells in the correct metabolic zones. Technical hurdles exist and will need to be overcome for gene-edited iPSC to iHLC rescue of arginase-1 deficiency, a rare urea cycle disorder.

  3. PERM Hypothesis: The Fundamental Machinery Able to Elucidate the Role of Xenobiotics and Hormesis in Cell Survival and Homeostasis

    Salvatore Chirumbolo

    2017-01-01

    Full Text Available In this article the Proteasome, Endoplasmic Reticulum and Mitochondria (PERM hypothesis is discussed. The complex machinery made by three homeostatic mechanisms involving the proteasome (P, endoplasmic reticulum (ER and mitochondria (M is addressed in order to elucidate the beneficial role of many xenobiotics, either trace metals or phytochemicals, which are spread in the human environment and in dietary habits, exerting their actions on the mechanisms underlying cell survival (apoptosis, cell cycle regulation, DNA repair and turnover, autophagy and stress response. The “PERM hypothesis” suggests that xenobiotics can modulate this central signaling and the regulatory engine made fundamentally by the ER, mitochondria and proteasome, together with other ancillary components such as peroxisomes, by acting on the energetic balance, redox system and macromolecule turnover. In this context, reactive species and stressors are fundamentally signalling molecules that could act as negative-modulating signals if PERM-mediated control is offline, impaired or dysregulated, as occurs in metabolic syndrome, degenerative disorders, chronic inflammation and cancer. Calcium is an important oscillatory input of this regulation and, in this hypothesis, it might play a role in maintaining the correct rhythm of this PERM modulation, probably chaotic in its nature, and guiding cells to a more drastic decision, such as apoptosis. The commonest effort sustained by cells is to maintain their survival balance and the proterome has the fundamental task of supporting this mechanism. Mild stress is probably the main stimulus in this sense. Hormesis is therefore re-interpreted in the light of this hypothetical model and that experimental evidence arising from flavonoid and hormesis reasearch.

  4. Pretreatment oral hygiene habits and survival of head and neck squamous cell carcinoma (HNSCC) patients.

    Friemel, Juliane; Foraita, Ronja; Günther, Kathrin; Heibeck, Mathias; Günther, Frauke; Pflueger, Maren; Pohlabeln, Hermann; Behrens, Thomas; Bullerdiek, Jörn; Nimzyk, Rolf; Ahrens, Wolfgang

    2016-03-11

    The survival time of patients with head and neck squamous cell carcinoma (HNSCC) is related to health behavior, such as tobacco smoking and alcohol consumption. Poor oral health (OH), dental care (DC) and the frequent use of mouthwash have been shown to represent independent risk factors for head and neck cancerogenesis, but their impact on the survival of HNSCC patients has not been systematically investigated. Two hundred seventy-six incident HNSCC cases recruited for the ARCAGE study were followed through a period of 6-10 years. Interview-based information on wearing of dentures, gum bleeding, teeth brushing, use of floss and dentist visits were grouped into weighted composite scores, i.e. oral health (OH) and dental care (DH). Use of mouthwash was assessed as frequency per day. Also obtained were other types of health behavior, such as smoking, alcohol drinking and diet, appreciated as both confounding and study variables. Endpoints were progression-free survival, overall survival and tumor-specific survival. Prognostic values were estimated using Kaplan-Meier analysis and Cox proportional hazards regression models. A good dental care score, summarizing annual dental visits, daily teeth cleaning and use of floss was associated with longer overall survival time (p = .001). The results of the Cox regression models similarly suggested a higher risk of tumor progression and shortened overall survival in patients with poor dental care, but the results lost their statistical significance after other types of health behavior had been controlled for. Frequent use of mouthwash (≥ 2 times/day) significantly increased the risk of tumor-specific death (HR = 2.26; CI = 1.19-4.32). Alcohol consumption and tobacco smoking were dose-dependently associated with tumor progression and shorter overall survival. Frequent mouthwash use of ≥ 2 times/day seems to elevate the risk of tumor-specific death in HNSCC patients. Good dental care scores are associated with longer overall

  5. Supplementation with apple enriched with L-arginine may improve metabolic control and survival rate in alloxan-induced diabetic rats.

    Escudero, Andrea; Petzold, Guillermo; Moreno, Jorge; Gonzalez, Marcelo; Junod, Julio; Aguayo, Claudio; Acurio, Jesenia; Escudero, Carlos

    2013-01-01

    Supplementation with L-arginine or fresh food with high content of this amino acid is associated with favorable effects in the metabolic control of diabetes. We aimed to determine whether supplementation with apples enriched with L-arginine offer additional benefits compared to L-arginine by itself in a preclinical study of diabetes. This study combines food-engineer technologies with in vivo and in vitro analysis. In vitro experiments show that cells derived from non-diabetic animals and exposed to high glucose (25 mM, 12 H) and cells isolated from alloxan-induced diabetic animals exhibited a reduction (∼50%) in the L-arginine uptake. This effect was reverted by L-arginine pretreatment (12 H) in both the normal and diabetes-derived cells. In preclinical studies, normoglycemic (n = 25) and diabetic groups (n = 50) were divided into subgroups that received either L-arginine (375 mg/kg per 10 days) or apple enriched with L-arginine or vehicle (control). In a preliminary analysis, supplementation with L-arginine by itself (50%) or apple enriched with L-arginine (100%) improve survival rate in the diabetic group compared to control (0%) at the end of the follow up (17 days). This phenomenon was associated with a partial but sustained high plasma level of L-arginine, as well as plasma concentration of nitrites and insulin in the L-arginine or apple + L-arginine groups after supplementation. Apple + L-arginine supplementation in diabetic animals induced the highest and longest effects in the level of these three markers among the studied groups. Therefore, apple enriched by L-arginine offers more benefits than L-arginine by itself in this preclinical study. Copyright © 2013 International Union of Biochemistry and Molecular Biology, Inc.

  6. The Growing Complexity of Cancer Cell Response to DNA-Damaging Agents: Caspase 3 Mediates Cell Death or Survival?

    Razmik Mirzayans

    2016-05-01

    Full Text Available It is widely stated that wild-type p53 either mediates the activation of cell cycle checkpoints to facilitate DNA repair and promote cell survival, or orchestrates apoptotic cell death following exposure to cancer therapeutic agents. This reigning paradigm has been challenged by numerous discoveries with different human cell types, including solid tumor-derived cell lines. Thus, activation of the p53 signaling pathway by ionizing radiation and other DNA-damaging agents hinders apoptosis and triggers growth arrest (e.g., through premature senescence in some genetic backgrounds; such growth arrested cells remain viable, secrete growth-promoting factors, and give rise to progeny with stem cell-like properties. In addition, caspase 3, which is best known for its role in the execution phase of apoptosis, has been recently reported to facilitate (rather than suppress DNA damage-induced genomic instability and carcinogenesis. This observation is consistent with an earlier report demonstrating that caspase 3 mediates secretion of the pro-survival factor prostaglandin E2, which in turn promotes enrichment of tumor repopulating cells. In this article, we review these and related discoveries and point out novel cancer therapeutic strategies. One of our objectives is to demonstrate the growing complexity of the DNA damage response beyond the conventional “repair and survive, or die” hypothesis.

  7. The influence of fractionation on cell survival and premature differentiation after carbon ion irradiation

    Wang Jufang; Li Renming; Guo Chuanling; Fournier, C.; K-Weyrather, W.

    2008-01-01

    To investigate the influence of fractionation on cell survival and radiation induced premature differentiation as markers for early and late effects after X-rays and carbon irradiation. Normal human fibroblasts NHDF, AG1522B and WI-38 were irradiated with 250 kV X-rays, or 266 MeV/u, 195 MeV/u and 11 MeV/u carbon ions. Cytotoxicity was measured by a clonogenic survival assay or by determination of the differentiation pattern. Experiments with high-energy carbon ions show that fractionation induced repair effects are similar to photon irradiation. The relative biological effective (RBE) 10 values for clonogenic survival are 1.3 and 1.6 for irradiation in one or two fractions for NHDF cells and around 1.2 for AG1522B cells regardless of the fractionation scheme. The RBE for a doubling of post mitotic fibroblasts (PMF) in the population is 1 for both single and two fractionated irradiation of NHDF cells. Using 11 MeV/u carbon ions, no repair effect can be seen in WI-38 cells. The RBE 10 for clonogenic survival is 3.2 for single irradiation and 4.9 for two fractionated irradiations. The RBE for a doubling of PMF is 3.1 and 5.0 for single and two fractionated irradiations, respectively. For both cell lines the effects of high-energy carbon ions representing the irradiation of the skin and the normal tissue in the entrance channel are similar to the effects of X-rays. The fractionation effects are maintained. For the lower energy, which is representative for the irradiation of the tumor region, RBE is enhanced for clonogenic survival as well as for premature terminal differentiation. Fractionation effects are not detectable. Consequently, the therapeutic ratio is significantly enhanced by fractionated irradiation with carbon ions. (author)

  8. A linear-quadratic model of cell survival considering both sublethal and potentially lethal radiation damage

    Rutz, H.P.; Coucke, P.A.; Mirimanoff, R.O.

    1991-01-01

    The authors assessed the dose-dependence of repair of potentially lethal damage in Chinese hamster ovary cells x-irradiated in vitro. The recovery ratio (RR) by which survival (SF) of the irradiated cells was enhanced increased exponentially with a linear and a quadratic component namely ζ and ψ: RR=exp(ζD+ψD 2 ). Survival of irradiated cells can thus be expressed by a combined linear-quadratic model considering 4 variables, namely α and β for the capacity of the cells to accumulate sublethal damage, and ζ and ψ for their capacity to repair potentially lethal damage: SF=exp((ζ-α)D+ (ψ-β)D 2 ). author. 26 refs.; 1 fig.; 1 tab

  9. Initial slope of human tumor cell survival curves: its modification by the oxic cell sensitizer beta-arabinofuranosyladenine

    Chavaudra, N.; Halimi, M.; Parmentier, C.; Gaillard, N.; Grinfeld, S.; Malaise, E.P.

    1989-01-01

    The initial slope of the survival curve, which is a characteristic of each tumor cell line, varies with the histological group of the tumor. It is one of the factors on which clinical radioresponsiveness depends. The DNA dependant DNA polymerase inhibitor beta-ara A acts as an oxic cell sensitizer. This study was carried out on human tumor cell lines to look for a correlation between the degree of radiosensitization induced by beta-ara A and the radiosensitivity of a given cell line. Six human tumor cell lines with different radiosensitivities were used (the survival rate at 2 Gy and D ranged from 20 to 73% and from 1.2 to 3.2 Gy, respectively). beta-ara A had a major toxic effect on all cell lines but this varied greatly from one cell line to another and was concentration dependant; this toxic effect was taken into account when calculating the surviving fractions. For all cell lines, beta-ara A acted as an oxic radiosensitizer and the radiosensitization was concentration dependant. Analysis of the survival curves of the 6 cell lines using the linear quadratic model showed that concentrations of beta-ara A between 200 and 1000 microM induced an increase in the linear component while the quadratic component underwent no systematic change. The sensitizing enhancement ratio (SER) measured from the Ds ratios, varied greatly from one line to another. For example, at a concentration of 500 microM, the extreme values of Ds ratios were 1.5 and 2.6. The radiosensitization is greater, the higher the radiosensitivity of the cell line studied during exponential growth. The results do not favor the use of beta-ara A in the treatment of intrinsically radioresistant human tumors

  10. Initial slope of human tumor cell survival curves: its modification by the oxic cell sensitizer beta-arabinofuranosyladenine

    Chavaudra, N.; Halimi, M.; Parmentier, C.; Gaillard, N.; Grinfeld, S.; Malaise, E.P.

    1989-05-01

    The initial slope of the survival curve, which is a characteristic of each tumor cell line, varies with the histological group of the tumor. It is one of the factors on which clinical radioresponsiveness depends. The DNA dependant DNA polymerase inhibitor beta-ara A acts as an oxic cell sensitizer. This study was carried out on human tumor cell lines to look for a correlation between the degree of radiosensitization induced by beta-ara A and the radiosensitivity of a given cell line. Six human tumor cell lines with different radiosensitivities were used (the survival rate at 2 Gy and D ranged from 20 to 73% and from 1.2 to 3.2 Gy, respectively). beta-ara A had a major toxic effect on all cell lines but this varied greatly from one cell line to another and was concentration dependant; this toxic effect was taken into account when calculating the surviving fractions. For all cell lines, beta-ara A acted as an oxic radiosensitizer and the radiosensitization was concentration dependant. Analysis of the survival curves of the 6 cell lines using the linear quadratic model showed that concentrations of beta-ara A between 200 and 1000 microM induced an increase in the linear component while the quadratic component underwent no systematic change. The sensitizing enhancement ratio (SER) measured from the Ds ratios, varied greatly from one line to another. For example, at a concentration of 500 microM, the extreme values of Ds ratios were 1.5 and 2.6. The radiosensitization is greater, the higher the radiosensitivity of the cell line studied during exponential growth. The results do not favor the use of beta-ara A in the treatment of intrinsically radioresistant human tumors.

  11. Pancreatic β-cells activate a JunB/ATF3-dependent survival pathway during inflammation

    Gurzov, E N; Barthson, J; Marhfour, I

    2012-01-01

    Destruction of insulin-producing pancreatic β-cells by local autoimmune inflammation is a hallmark of type 1 diabetes. Histochemical analysis of pancreases from non-obese diabetic mice indicated activation of the transcription factor JunB/AP-1 (activator protein-1) after autoimmune infiltration......-cells and human islet cells against pro-inflammatory mediators. These results were confirmed in genetically modified islets derived from Ubi-JunB transgenic mice. Our findings identify ATF3 as a novel downstream target of JunB in the survival mechanism of β-cells under inflammatory stress....

  12. Laser Phototherapy Enhances Mesenchymal Stem Cells Survival in Response to the Dental Adhesives

    Ivana Márcia Alves Diniz

    2015-01-01

    Full Text Available Background. We investigated the influence of laser phototherapy (LPT on the survival of human mesenchymal stem cells (MSCs submitted to substances leached from dental adhesives. Method. MSCs were isolated and characterized. Oral mucosa fibroblasts and osteoblast-like cells were used as comparative controls. Cultured medium conditioned with two adhesive systems was applied to the cultures. Cell monolayers were exposed or not to LPT. Laser irradiations were performed using a red laser (GaAlAs, 780 nm, 0.04 cm2, 40 mW, 1 W/cm2, 0.4 J, 10 seconds, 1 point, 10 J/cm2. After 24 h, cell viability was assessed by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide reduction assay. Data were statistically compared by ANOVA followed by Tukey’s test (P<0.05. Results. Different cell types showed different viabilities in response to the same materials. Substances leached from adhesives were less cytotoxic to MSCs than to other cell types. Substances leached from Clearfil SE Bond were highly cytotoxic to all cell types tested, except to the MSCs when applied polymerized and in association with LPT. LPT was unable to significantly increase the cell viability of fibroblasts and osteoblast-like cells submitted to the dental adhesives. Conclusion. LPT enhances mesenchymal stem cells survival in response to substances leached from dental adhesives.

  13. N-methyl-D-aspartate promotes the survival of cerebellar granule cells: pharmacological characterization

    Balázs, R; Hack, N; Jørgensen, Ole Steen

    1989-01-01

    The survival of cerebellar granule cells in culture is promoted by chronic exposure to N-methyl-D-aspartate (NMDA). The effect is due to the stimulation of 'conventional' NMDA receptor-ionophore complex: it is concentration dependent, voltage dependent and blocked by the selective antagonists D-2...

  14. Effects of cell-bound microcystins on survival and feeding of Daphnia spp

    Rohrlack, T; Dittmann, E; Börner, T

    2001-01-01

    The influence of cell-bound microcystins on the survival time and feeding rates of six Daphnia clones belonging to five common species was studied. To do this, the effects of the microcystin-producing Microcystis strain PCC7806 and its mutant, which has been genetically engineered to knock out mi...

  15. Survival of Er(a+) red cells in a patient with allo-anti-Era

    Thompson, H.W.; Skradski, K.J.; Thoreson, J.R.; Polesky, H.F.

    1985-01-01

    51 Chromium-labeled Er(a+) red cells survived nearly normally (T1/2 of 21 days) in a patient with allo-anti-Era. Transfusion of Er(a+) blood was without significant reaction and did not affect the anti-Era titer

  16. Circulating tumor cells, disease recurrence and survival in newly diagnosed breast cancer

    Franken, Bas; De Groot, Marco R.; Mastboom, Walter J.B.; Vermes, I.; van der Palen, Jacobus Adrianus Maria; Tibbe, Arjan G.J.; Terstappen, Leonardus Wendelinus Mathias Marie

    2012-01-01

    Introduction The presence of circulating tumor cells (CTC) is an independent prognostic factor for progression-free survival and breast cancer-related death (BRD) for patients with metastatic breast cancer beginning a new line of systemic therapy. The current study was undertaken to explore whether

  17. Overall survival after immunotherapy, tyrosine kinase inhibitors and surgery in treatment of metastatic renal cell cancer

    de Lichtenberg, Trine Honnens; Hermann, Gregers G.; Rorth, Mikael

    2014-01-01

    Abstract Objective. The aim of this study was to evaluate overall survival (OS) after treatment of metastatic renal cell carcinoma (mRCC) following the introduction of tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin (mTOR) inhibitors. Material and methods. One-hundred and forty...

  18. Metastatic clear cell eccrine hidradenocarcinoma of the vulva: survival after primary surgical resection.

    Massad, L S; Bitterman, P; Clarke-Pearson, D L

    1996-05-01

    A case of clear cell eccrine hidradenocarcinoma of the vulva metastatic to regional lymph nodes with long survival after surgical resection is presented. Like the only other case reported to date, this suggests that surgical therapy alone may be adequate, even when metastasis is present.

  19. Genomic instability induced by 137Cs γ-ray irradiation in CHL surviving cells

    Yue Jingyin; Liu Bingchen; Wu Hongying; Zhou Jiwen; Mu Chuanjie

    1999-01-01

    Objective: To study in parallel several possible manifestations of instability of surviving CHL cells after irradiation, namely the frequencies of mutation at locus, micronuclei and apoptosis. Methods: The frequencies of mutation at HGPRT locus, micronuclei and apoptosis were assayed at various times in surviving cells irradiated with γ-rays. Results: The surviving cells showed a persistently increased frequency of mutation at the HGPRT locus after irradiation until 53 days. Mutant fraction as high as 10 -4 was scored, tens of times higher than those assayed in control cells studied in parallel. The frequency of bi nucleated cells with micronuclei determined within 24 hours after irradiation increased with dose and reached a peak value of (26.58 +- 2.48)% at 3 Gy, decreasing at higher doses to a plateau around 20%. The micronucleus frequency decreased steeply to about (14.47 +- 2.39)% within the first 3 days post-irradiation, and fluctuated at around 10% up to 56 days post-irradiation. The delayed efficiency of irradiated cells was significantly decreased. The frequency of apoptosis peaked about (24.90 +- 4.72)% at 10 Gy 48 h post-irradiation (γ-ray dose between 3-10 Gy) and then decreased to about 12% within 3 days. It was significantly higher than in control cells until 14 days. Conclusions: It shows that genomic instability induced by radiation can be transmitted to the progeny of surviving cells and may take many forms of expression such as lethal mutation, chromosome aberrations, gene mutation, etc

  20. Survival and DNA repair in ultraviolet-irradiated haploid and diploid cultured frog cells

    Freed, J.J.; Hoess, R.H.; Angelosanto, F.A.; Massey, H.C. Jr.

    1979-01-01

    Survival and repair of DNA following ultraviolet (254-nm) radiation have been investigated in ICR 2A, a cultured cell line from haploid embryos of the grassfrog, Rana pipiens. Survival curves from cells recovering in the dark gave mean lethal dose value (D 0 ) in the range 1.5-1.7 Jm -2 for both haploid and diploid cell stocks. The only significant difference observed between haploids and diploids was in the extent of the shoulder at low fluence (Dsub(q)), the value for exponentially multiplying diploid cells (3.0 Jm -2 ) being higher than that found for haploids (1.2 Jm -2 ). Irradiation of cultures reversibly blocked in the G1 phase of the cell cycle gave survival-curve coefficients indistinguishable between haploids and diploids. Post-irradiation exposure to visible light restored colony-forming capacity and removed chromatographically estimated pyrimidine dimers from DNA at the same rates. After fluences killing 90% of the cells, complete restoration of survival was obtained after 60-min exposure to 500 foot-candles, indicating that in this range lethality is entirely photoreversible and therefore attributable to pyrimidine dimers in DNA. Dimer removal required illumination following ultraviolet exposure, intact cells and physiological temperature, implying that the photoreversal involved DNA photolyase activity. Excision-repair capacity was slight, since no loss of dimers could be detected chromoatographically during up to 48 h incubation in the dark and since autoradiographically detected 'unscheduled DNA synthesis' was limited to a 2-fold increase saturated at 10 Jm -2 . These properties make ICR 2A frog cells useful to explore how DNA-repair pathways influence mutant yield. (Auth.)

  1. Radiation survival of cells from spheroids grown in different oxygen concentrations

    Franko, A.J.; Sutherland, R.M.

    1979-01-01

    The position of the internal, chronically hypoxic cells in spheroids was varied by alterations in the oxygen concentration in the growth medium. Such alterations were expected to cause large changes in the size of the radiobiologically hypoxic fraction. This was tested by growing and irradiating spheroids in oxygen concentrations between 5 and 20.3%, ensuring that the irradiation and growth conditions were as similar as possible. The survival curves appeared to be linear below a surviving fraction of 3 x 10 -2 , and the slopes were intermediate between the slopes of control curves for cells from spheroids irradiated in nitrogen or when fully oxygenated. Thus direct estimates of the hypoxic fractions could not be made. Two models of oxygen diffusion might explain the data. One model assumes that a large fraction of cells was fully hypoxic (radiobiologically) and that these internal, G 1 -confined, chronically hypoxic cells had a lower inherent radioresistance than the outer proliferating cells. Evidence was presented which indicated that this model was unlikely to be correct. The other model assumes that the inherent radioresistance was equal throughout the spheroid, and that the innermost cells died before the oxygen concentration was reduced sufficiently to cause full hypoxic protection. Theoretical survival curves based on this model were generated using the measured geometries ofthe spheroids and multitarget single-hit survival theory. Acceptable agreement with the postulate that the innermost cells of spheroids die at between 0.2 and 0.4% oxygen was obtained. These data may have implications regarding the relative contributions of chronic and acute hypoxia to the fraction of hypoxic cells in tumors

  2. Improved survival of mesenchymal stem cells by macrophage migration inhibitory factor

    Xia, Wenzheng; Xie, Congying; Jiang, Miaomiao; Hou, Meng

    2015-01-01

    Macrophage migration inhibitory factor (MIF) is a critical inflammatory cytokine that was recently associated with progenitor cell survival and potently inhibits apoptosis. We examined the protective effect of MIF on hypoxia/serum deprivation (SD)-induced apoptosis of mesenchymal stem cells (MSCs), as well as the possible mechanisms. MSCs were obtained from rat bone marrow and cultured in vitro. Apoptosis was induced by culturing MSCs under hypoxia/SD conditions for up to 24?h and assessed by...

  3. Adaptation of red cell enzymes and intermediates in metabolic disorders.

    Goebel, K M; Goebel, F D; Neitzert, A; Hausmann, L; Schneider, J

    1975-01-01

    The metabolic activity of the red cell glycolytic pathway hexose monophosphate shunt (HMP) with dependent glutathione system was studied in patients with hyperthyroidism (n = 10), hyperlipoproteinemia (n = 16), hypoglycemia (n = 25) and hyperglycemia (n = 23). In uncontrolled diabetics and patients with hyperthyroidism the mean value of glucose phosphate isomerase (GPI), glucose-6-phosphate dehydrogenase (G-6-PD), glutathione reductase (GR) was increased, whereas these enzyme activities were reduced in patients with hypoglycemia. Apart from a few values of hexokinase (HK) which were lower than normal the results in hyperlipoproteinemia patients remained essentially unchanged, including the intermediates such as 2,3-diphosphoglycerate (2,3-DPG), adenosine triphosphate (ATP) and reduced glutathione (GSH). While increased rates of 2,3-DPG and ATP in hypoglycemia patients were obtained, these substrates were markedly reduced in diabetics.

  4. Cell-free protein synthesis enabled rapid prototyping for metabolic engineering and synthetic biology

    Lihong Jiang

    2018-06-01

    Full Text Available Advances in metabolic engineering and synthetic biology have facilitated the manufacturing of many valuable-added compounds and commodity chemicals using microbial cell factories in the past decade. However, due to complexity of cellular metabolism, the optimization of metabolic pathways for maximal production represents a grand challenge and an unavoidable barrier for metabolic engineering. Recently, cell-free protein synthesis system (CFPS has been emerging as an enabling alternative to address challenges in biomanufacturing. This review summarizes the recent progresses of CFPS in rapid prototyping of biosynthetic pathways and genetic circuits (biosensors to speed up design-build-test (DBT cycles of metabolic engineering and synthetic biology. Keywords: Cell-free protein synthesis, Metabolic pathway optimization, Genetic circuits, Metabolic engineering, Synthetic biology

  5. Sema3C Promotes the Survival and Tumorigenicity of Glioma Stem Cells through Rac1 Activation

    Jianghong Man

    2014-12-01

    Full Text Available Summary: Different cancer cell compartments often communicate through soluble factors to facilitate tumor growth. Glioma stem cells (GSCs are a subset of tumor cells that resist standard therapy to contribute to disease progression. How GSCs employ a distinct secretory program to communicate with and nurture each other over the nonstem tumor cell (NSTC population is not well defined. Here, we show that GSCs preferentially secrete Sema3C and coordinately express PlexinA2/D1 receptors to activate Rac1/nuclear factor (NF-κB signaling in an autocrine/paracrine loop to promote their own survival. Importantly, Sema3C is not expressed in neural progenitor cells (NPCs or NSTCs. Disruption of Sema3C induced apoptosis of GSCs, but not NPCs or NSTCs, and suppressed tumor growth in orthotopic models of glioblastoma. Introduction of activated Rac1 rescued the Sema3C knockdown phenotype in vivo. Our study supports the targeting of Sema3C to break this GSC-specific autocrine/paracrine loop in order to improve glioblastoma treatment, potentially with a high therapeutic index. : Glioma stem cells (GSCs have a high capacity for self-renewal, invasion, and survival. How they communicate with each other to survive and maintain their identity is not clear. Man et al. now show that GSCs have co-opted a neurodevelopmental program to activate Rac1 to promote defining features of GSCs.

  6. Cyclophilin B Supports Myc and Mutant p53 Dependent Survival of Glioblastoma Multiforme Cells

    Choi, Jae Won; Schroeder, Mark A.; Sarkaria, Jann N.; Bram, Richard J.

    2014-01-01

    Glioblastoma multiforme (GBM) is an aggressive, treatment-refractory type of brain tumor for which effective therapeutic targets remain important to identify. Here we report that cyclophilin B (CypB), a prolyl isomerase residing in the endoplasmic reticulum (ER), provides an essential survival signal in GBM cells. Analysis of gene expression databases revealed that CypB is upregulated in many cases of malignant glioma. We found that suppression of CypB reduced cell proliferation and survival in human GBM cells in vitro and in vivo. We also found that treatment with small molecule inhibitors of cyclophilins, including the approved drug cyclosporine, greatly reduced the viability of GBM cells. Mechanistically, depletion or pharmacologic inhibition of CypB caused hyperactivation of the oncogenic RAS-MAPK pathway, induction of cellular senescence signals, and death resulting from loss of MYC, mutant p53, Chk1 and JAK/STAT3 signaling. Elevated reactive oxygen species, ER expansion and abnormal unfolded protein responses in CypB-depleted GBM cells indicated that CypB alleviates oxidative and ER stresses and coordinates stress adaptation responses. Enhanced cell survival and sustained expression of multiple oncogenic proteins downstream of CypB may thus contribute to the poor outcome of GBM tumors. Our findings link chaperone-mediated protein folding in the ER to mechanisms underlying oncogenic transformation, and they make CypB an attractive and immediately targetable molecule for GBM therapy. PMID:24272483

  7. Cyclophilin B supports Myc and mutant p53-dependent survival of glioblastoma multiforme cells.

    Choi, Jae Won; Schroeder, Mark A; Sarkaria, Jann N; Bram, Richard J

    2014-01-15

    Glioblastoma multiforme is an aggressive, treatment-refractory type of brain tumor for which effective therapeutic targets remain important to identify. Here, we report that cyclophilin B (CypB), a prolyl isomerase residing in the endoplasmic reticulum (ER), provides an essential survival signal in glioblastoma multiforme cells. Analysis of gene expression databases revealed that CypB is upregulated in many cases of malignant glioma. We found that suppression of CypB reduced cell proliferation and survival in human glioblastoma multiforme cells in vitro and in vivo. We also found that treatment with small molecule inhibitors of cyclophilins, including the approved drug cyclosporine, greatly reduced the viability of glioblastoma multiforme cells. Mechanistically, depletion or pharmacologic inhibition of CypB caused hyperactivation of the oncogenic RAS-mitogen-activated protein kinase pathway, induction of cellular senescence signals, and death resulting from loss of MYC, mutant p53, Chk1, and Janus-activated kinase/STAT3 signaling. Elevated reactive oxygen species, ER expansion, and abnormal unfolded protein responses in CypB-depleted glioblastoma multiforme cells indicated that CypB alleviates oxidative and ER stresses and coordinates stress adaptation responses. Enhanced cell survival and sustained expression of multiple oncogenic proteins downstream of CypB may thus contribute to the poor outcome of glioblastoma multiforme tumors. Our findings link chaperone-mediated protein folding in the ER to mechanisms underlying oncogenic transformation, and they make CypB an attractive and immediately targetable molecule for glioblastoma multiforme therapy.

  8. Hair Follicle Dermal Sheath Derived Cells Improve Islet Allograft Survival without Systemic Immunosuppression

    Xiaojie Wang

    2015-01-01

    Full Text Available Immunosuppressive drugs successfully prevent rejection of islet allografts in the treatment of type I diabetes. However, the drugs also suppress systemic immunity increasing the risk of opportunistic infection and cancer development in allograft recipients. In this study, we investigated a new treatment for autoimmune diabetes using naturally immune privileged, hair follicle derived, autologous cells to provide localized immune protection of islet allotransplants. Islets from Balb/c mouse donors were cotransplanted with syngeneic hair follicle dermal sheath cup cells (DSCC, group 1 or fibroblasts (FB, group 2 under the kidney capsule of immune-competent, streptozotocin induced, diabetic C57BL/6 recipients. Group 1 allografts survived significantly longer than group 2 (32.2 ± 12.2 versus 14.1 ± 3.3 days, P<0.001 without administration of any systemic immunosuppressive agents. DSCC reduced T cell activation in the renal lymph node, prevented graft infiltrates, modulated inflammatory chemokine and cytokine profiles, and preserved better beta cell function in the islet allografts, but no systemic immunosuppression was observed. In summary, DSCC prolong islet allograft survival without systemic immunosuppression by local modulation of alloimmune responses, enhancing of beta cell survival, and promoting of graft revascularization. This novel finding demonstrates the capacity of easily accessible hair follicle cells to be used as local immunosuppression agents in islet transplantation.

  9. Towards high resolution analysis of metabolic flux in cells and tissues.

    Sims, James K; Manteiga, Sara; Lee, Kyongbum

    2013-10-01

    Metabolism extracts chemical energy from nutrients, uses this energy to form building blocks for biosynthesis, and interconverts between various small molecules that coordinate the activities of cellular pathways. The metabolic state of a cell is increasingly recognized to determine the phenotype of not only metabolically active cell types such as liver, muscle, and adipose, but also other specialized cell types such as neurons and immune cells. This review focuses on methods to quantify intracellular reaction flux as a measure of cellular metabolic activity, with emphasis on studies involving cells of mammalian tissue. Two key areas are highlighted for future development, single cell metabolomics and noninvasive imaging, which could enable spatiotemporally resolved analysis and thereby overcome issues of heterogeneity, a distinctive feature of tissue metabolism. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Molecular Imaging of Stem Cells: Tracking Survival, Biodistribution, Tumorigenicity, and Immunogenicity

    Eugene Gu, Wen-Yi Chen, Jay Gu, Paul Burridge, Joseph C. Wu

    2012-01-01

    Full Text Available Being able to self-renew and differentiate into virtually all cell types, both human embryonic stem cells (hESCs and induced pluripotent stem cells (iPSCs have exciting therapeutic implications for myocardial infarction, neurodegenerative disease, diabetes, and other disorders involving irreversible cell loss. However, stem cell biology remains incompletely understood despite significant advances in the field. Inefficient stem cell differentiation, difficulty in verifying successful delivery to the target organ, and problems with engraftment all hamper the transition from laboratory animal studies to human clinical trials. Although traditional histopathological techniques have been the primary approach for ex vivo analysis of stem cell behavior, these postmortem examinations are unable to further elucidate the underlying mechanisms in real time and in vivo. Fortunately, the advent of molecular imaging has led to unprecedented progress in understanding the fundamental behavior of stem cells, including their survival, biodistribution, immunogenicity, and tumorigenicity in the targeted tissues of interest. This review summarizes various molecular imaging technologies and how they have advanced the current understanding of stem cell survival, biodistribution, immunogenicity, and tumorigenicity.

  11. Androgen receptor signaling is required for androgen-sensitive human prostate cancer cell proliferation and survival

    Day Wanda V

    2005-04-01

    Full Text Available Abstract Background Androgens and androgen receptors (AR regulate normal prostate development and growth. They also are involved in pathological development of prostatic diseases, including benign prostatic hyperplasia (BPH and prostate cancer (PCa. Antiandrogen therapy for PCa, in conjunction with chemical or surgical castration, offers initial positive responses and leads to massive prostate cell death. However, cancer cells later appear as androgen-independent PCa. To investigate the role of AR in prostate cell proliferation and survival, we introduced a vector-based small interfering RNA (siRNA. This siRNA targeted 5'-untranslated region of AR mRNA for extended suppression of AR expression in androgen-sensitive human prostate LNCaP cells. Results The siRNA design successfully suppressed endogenous AR expression, as revealed by western blotting and immunofluorescence staining in LNCaP cells. LNCaP cells did not proliferate in the absence of AR and underwent apoptosis, based on elevated phospho-Histone H2B expression and higher number of apoptotic body as compared to control cells. Conclusion We demonstrated that AR is vital for prostate cell proliferation and survival in this androgen-sensitive prostate cell line. These results further strengthen the hypothesis that AR can be a therapeutic target for treating androgen-sensitive stages of PCa. Unlike antiandorgens, however, siRNA targeting AR provides a direct inactivation of AR function through the suppression of AR protein expression.

  12. Marital status and survival of patients with oral cavity squamous cell carcinoma: a population-based study

    Shi, Xiao; Zhang, Ting-ting; Hu, Wei-ping; Ji, Qing-hai

    2017-01-01

    Background The relationship between marital status and oral cavity squamous cell carcinoma (OCSCC) survival has not been explored. The objective of our study was to evaluate the impact of marital status on OCSCC survival and investigate the potential mechanisms. Results Married patients had better 5-year cancer-specific survival (CSS) (66.7% vs 54.9%) and 5-year overall survival (OS) (56.0% vs 41.1%). In multivariate Cox regression models, unmarried patients also showed higher mortality risk ...

  13. Delayed reproductive death as a dominant phenotype in cell clones surviving X-irradiation

    Chang, W.P.; Little, J.B.

    1992-01-01

    Residual damage manifested as reduced cloning efficiency was observed in many of the cloned progeny of Chinese hamster ovary (CHO) cells and human carcinoma SQ-20B cells surviving X-irradiation. This stable phenotype, which we have termed delayed reproductive death, persisted for >50 generations of cell replication post-irradiation. Clones showing this phenotype were aneuploid, and formed colonies with a high proportion of giant cells. By somatic cell hybridization of CHO clones, the delayed reproductive death phenotype was found to be a dominant trait; the cloning efficiency of hybrid clones was persistently depressed, as compared with that of control hybrid cells. These results suggest that delayed reproductive death represents a specific cellular response that may persist in some of the progeny of mammalian cells for long periods after X-irradiation. (author)

  14. Pluripotent stem cells with normal or reduced self renewal survive lethal irradiation

    Brecher, G.; Neben, S.; Yee, M.; Bullis, J.; Cronkite, E.P.

    1988-01-01

    Transfusion with 10,000 or 20,000 marrow cells resulted in 30+ days survival of 15%-50% of mice exposed to an Ld90 or LD100 or radiation. The use of congenic mice with alloenzyme markers permitted the identification of host and donor cells in the peripheral blood of transfused animals. Donor cells were present initially in all hosts. Between 55% and 92% of the animals became 100% host type by 12-24 weeks after transfusion in three separate experiments. To explore whether the temporary repopulation by donor cells was due to short-lived stem cells, the marrows of several primary hosts were transfused into secondary, lethally irradiated hosts. Some of the retransplanted primary donor and host cells persisted only temporarily. It is suggested that some of the donor stem cells in both the primary and secondary hosts had an intrinsically shortened life span

  15. Immunohistochemical detection of cdc2 is useful in predicting survival in patients with mantle cell lymphoma.

    Hui, David; Reiman, Tony; Hanson, John; Linford, Rick; Wong, Winson; Belch, Andrew; Lai, Raymond

    2005-09-01

    Recent cDNA microarray studies have reported the prognostic value of several genes in mantle cell lymphoma patients. We aimed to validate the prognostic significance of three of these genes: alpha-tubulin, cdc2, and CENP-F. The protein expression of alpha-tubulin, cdc2, and CENP-F was assessed using immunohistochemistry. Their immunoreactivity in 48 formalin-fixed/paraffin-embedded mantle cell lymphoma tumors was determined by estimating the percentage of positive cells. These results were correlated with the expression of proliferation marker Ki67 and survival. Of these 48 mantle cell lymphoma patients, 41 were men and seven were women. The median age at time of diagnosis was 64.5 years, and the overall median survival was 40 months. In benign lymph nodes, the expression of cdc2 and alpha-tubulin was restricted to the germinal centers; mantle zones were negative. Expression of CENP-F was more uniformly distributed. In mantle cell lymphoma, Ki67 significantly correlated with all three markers (P50%) and cdc2 (>25%) significantly correlated with shorter survival (Por=2 correlated with worse clinical outcome, and high clinical stage (ie 4 vs survival. The prognostic significance of cdc2 and Ki67 was independent of international prognostic index and clinical stage. We have validated the prognostic value of cdc2, and confirmed that of Ki67, in a cohort of mantle cell lymphoma patients. Immunohistochemical detection of cdc2 and Ki67 may be a useful and simple method in evaluating the prognosis of mantle cell lymphoma patients.

  16. Osteocalcin protects pancreatic beta cell function and survival under high glucose conditions

    Kover, Karen, E-mail: kkover@cmh.edu [Division of Endocrine/Diabetes, Children' s Mercy Hospital & Clinics, Kansas City, MO 64108 (United States); University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108 (United States); Yan, Yun; Tong, Pei Ying; Watkins, Dara; Li, Xiaoyu [Division of Endocrine/Diabetes, Children' s Mercy Hospital & Clinics, Kansas City, MO 64108 (United States); University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108 (United States); Tasch, James; Hager, Melissa [Kansas City University Medical Biosciences, Kansas City, MO (United States); Clements, Mark; Moore, Wayne V. [Division of Endocrine/Diabetes, Children' s Mercy Hospital & Clinics, Kansas City, MO 64108 (United States); University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108 (United States)

    2015-06-19

    Diabetes is characterized by progressive beta cell dysfunction and loss due in part to oxidative stress that occurs from gluco/lipotoxicity. Treatments that directly protect beta cell function and survival in the diabetic milieu are of particular interest. A growing body of evidence suggests that osteocalcin, an abundant non-collagenous protein of bone, supports beta cell function and proliferation. Based on previous gene expression data by microarray, we hypothesized that osteocalcin protects beta cells from glucose-induced oxidative stress. To test our hypothesis we cultured isolated rat islets and INS-1E cells in the presence of normal, high, or high glucose ± osteocalcin for up to 72 h. Oxidative stress and viability/mitochondrial function were measured by H{sub 2}O{sub 2} assay and Alamar Blue assay, respectively. Caspase 3/7 activity was also measured as a marker of apoptosis. A functional test, glucose stimulated insulin release, was conducted and expression of genes/protein was measured by qRT-PCR/western blot/ELISA. Osteocalcin treatment significantly reduced high glucose-induced H{sub 2}O{sub 2} levels while maintaining viability/mitochondrial function. Osteocalcin also significantly improved glucose stimulated insulin secretion and insulin content in rat islets after 48 h of high glucose exposure compared to untreated islets. As expected sustained high glucose down-regulated gene/protein expression of INS1 and BCL2 while increasing TXNIP expression. Interestingly, osteocalcin treatment reversed the effects of high glucose on gene/protein expression. We conclude that osteocalcin can protect beta cells from the negative effects of glucose-induced oxidative stress, in part, by reducing TXNIP expression, thereby preserving beta cell function and survival. - Highlights: • Osteocalcin reduces glucose-induced oxidative stress in beta cells. • Osteocalcin preserves beta cell function and survival under stress conditions. • Osteocalcin reduces glucose

  17. Osteocalcin protects pancreatic beta cell function and survival under high glucose conditions

    Kover, Karen; Yan, Yun; Tong, Pei Ying; Watkins, Dara; Li, Xiaoyu; Tasch, James; Hager, Melissa; Clements, Mark; Moore, Wayne V.

    2015-01-01

    Diabetes is characterized by progressive beta cell dysfunction and loss due in part to oxidative stress that occurs from gluco/lipotoxicity. Treatments that directly protect beta cell function and survival in the diabetic milieu are of particular interest. A growing body of evidence suggests that osteocalcin, an abundant non-collagenous protein of bone, supports beta cell function and proliferation. Based on previous gene expression data by microarray, we hypothesized that osteocalcin protects beta cells from glucose-induced oxidative stress. To test our hypothesis we cultured isolated rat islets and INS-1E cells in the presence of normal, high, or high glucose ± osteocalcin for up to 72 h. Oxidative stress and viability/mitochondrial function were measured by H 2 O 2 assay and Alamar Blue assay, respectively. Caspase 3/7 activity was also measured as a marker of apoptosis. A functional test, glucose stimulated insulin release, was conducted and expression of genes/protein was measured by qRT-PCR/western blot/ELISA. Osteocalcin treatment significantly reduced high glucose-induced H 2 O 2 levels while maintaining viability/mitochondrial function. Osteocalcin also significantly improved glucose stimulated insulin secretion and insulin content in rat islets after 48 h of high glucose exposure compared to untreated islets. As expected sustained high glucose down-regulated gene/protein expression of INS1 and BCL2 while increasing TXNIP expression. Interestingly, osteocalcin treatment reversed the effects of high glucose on gene/protein expression. We conclude that osteocalcin can protect beta cells from the negative effects of glucose-induced oxidative stress, in part, by reducing TXNIP expression, thereby preserving beta cell function and survival. - Highlights: • Osteocalcin reduces glucose-induced oxidative stress in beta cells. • Osteocalcin preserves beta cell function and survival under stress conditions. • Osteocalcin reduces glucose-induced TXNIP

  18. Identifying anti-growth factors for human cancer cell lines through genome-scale metabolic modeling

    Ghaffari, Pouyan; Mardinoglu, Adil; Asplund, Anna

    2015-01-01

    Human cancer cell lines are used as important model systems to study molecular mechanisms associated with tumor growth, hereunder how genomic and biological heterogeneity found in primary tumors affect cellular phenotypes. We reconstructed Genome scale metabolic models (GEMs) for eleven cell lines...... based on RNA-Seq data and validated the functionality of these models with data from metabolite profiling. We used cell line-specific GEMs to analyze the differences in the metabolism of cancer cell lines, and to explore the heterogeneous expression of the metabolic subsystems. Furthermore, we predicted...... for inhibition of cell growth may provide leads for the development of efficient cancer treatment strategies....

  19. Bmi1 overexpression in the cerebellar granule cell lineage of mice affects cell proliferation and survival without initiating medulloblastoma formation

    Hourinaz Behesti

    2013-01-01

    BMI1 is a potent inducer of neural stem cell self-renewal and neural progenitor cell proliferation during development and in adult tissue homeostasis. It is overexpressed in numerous human cancers – including medulloblastomas, in which its functional role is unclear. We generated transgenic mouse lines with targeted overexpression of Bmi1 in the cerebellar granule cell lineage, a cell type that has been shown to act as a cell of origin for medulloblastomas. Overexpression of Bmi1 in granule cell progenitors (GCPs led to a decrease in cerebellar size due to decreased GCP proliferation and repression of the expression of cyclin genes, whereas Bmi1 overexpression in postmitotic granule cells improved cell survival in response to stress by altering the expression of genes in the mitochondrial cell death pathway and of Myc and Lef-1. Although no medulloblastomas developed in ageing cohorts of transgenic mice, crosses with Trp53−/− mice resulted in a low incidence of medulloblastoma formation. Furthermore, analysis of a large collection of primary human medulloblastomas revealed that tumours with a BMI1high TP53low molecular profile are significantly enriched in Group 4 human medulloblastomas. Our data suggest that different levels and timing of Bmi1 overexpression yield distinct cellular outcomes within the same cellular lineage. Importantly, Bmi1 overexpression at the GCP stage does not induce tumour formation, suggesting that BMI1 overexpression in GCP-derived human medulloblastomas probably occurs during later stages of oncogenesis and might serve to enhance tumour cell survival.

  20. β-cell function is associated with metabolic syndrome in Mexican subjects

    Baez-Duarte, Blanca G; Sánchez-Guillén, María Del Carmen; Pérez-Fuentes, Ricardo; Zamora-Ginez, Irma; Leon-Chavez, Bertha Alicia; Revilla-Monsalve, Cristina; Islas-Andrade, Sergio

    2010-01-01

    Aims The clinical diagnosis of metabolic syndrome does not find any parameters to evaluate the insulin sensitivity (IS) or β-cell function. The evaluation of these parameters would detect early risk of developing metabolic syndrome. The aim of this study is to determine the relationship between β-cell function and presence of metabolic syndrome in Mexican subjects. Material and methods This study is part of the Mexican Survey on the Prevention of Diabetes (MexDiab Study) with headquarters in ...

  1. Oral cancer/endothelial cell fusion experiences nuclear fusion and acquisition of enhanced survival potential

    Song, Kai; Song, Yong; Zhao, Xiao-Ping; Shen, Hui; Wang, Meng; Yan, Ting-lin; Liu, Ke; Shang, Zheng-jun

    2014-01-01

    Most previous studies have linked cancer–macrophage fusion with tumor progression and metastasis. However, the characteristics of hybrid cells derived from oral cancer and endothelial cells and their involvement in cancer remained unknown. Double-immunofluorescent staining and fluorescent in situ hybridization (FISH) were performed to confirm spontaneous cell fusion between eGFP-labeled human umbilical vein endothelial cells (HUVECs) and RFP-labeled SCC9, and to detect the expression of vementin and cytokeratin 18 in the hybrids. The property of chemo-resistance of such hybrids was examined by TUNEL assay. The hybrid cells in xenografted tumor were identified by FISH and GFP/RFP dual-immunofluoresence staining. We showed that SCC9 cells spontaneously fused with cocultured endothelial cells, and the resultant hybrid cells maintained the division and proliferation activity after re-plating and thawing. Such hybrids expressed markers of both parental cells and became more resistant to chemotherapeutic drug cisplatin as compared to the parental SCC9 cells. Our in vivo data indicated that the hybrid cells contributed to tumor composition by using of immunostaining and FISH analysis, even though the hybrid cells and SCC9 cells were mixed with 1:10,000, according to the FACS data. Our study suggested that the fusion events between oral cancer and endothelial cells undergo nuclear fusion and acquire a new property of drug resistance and consequently enhanced survival potential. These experimental findings provide further supportive evidence for the theory that cell fusion is involved in cancer progression. - Highlights: • The fusion events between oral cancer and endothelial cells undergo nuclear fusion. • The resulting hybrid cells acquire a new property of drug resistance. • The resulting hybrid cells express the markers of both parental cells (i.e. vimentin and cytokeratin 18). • The hybrid cells contribute to tumor repopulation in vivo

  2. Oral cancer/endothelial cell fusion experiences nuclear fusion and acquisition of enhanced survival potential

    Song, Kai [Department of Oral and Maxillofacial Surgery, The Affiliated Hospital of Qingdao University, Shandong Province (China); The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine Ministry of Education, Wuhan University, Wuhan (China); Song, Yong [The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine Ministry of Education, Wuhan University, Wuhan (China); Department of Stomatology, Liu Zhou People' s Hospital, Guangxi (China); Zhao, Xiao-Ping; Shen, Hui; Wang, Meng; Yan, Ting-lin [The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine Ministry of Education, Wuhan University, Wuhan (China); Liu, Ke, E-mail: liuke.1999@aliyun.com [Department of Oral and Maxillofacial-Head and Neck oncology, School and Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan 430079 (China); The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine Ministry of Education, Wuhan University, Wuhan (China); Shang, Zheng-jun, E-mail: shangzhengjun@hotmail.com [Department of Oral and Maxillofacial-Head and Neck oncology, School and Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan 430079 (China); The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine Ministry of Education, Wuhan University, Wuhan (China)

    2014-10-15

    Most previous studies have linked cancer–macrophage fusion with tumor progression and metastasis. However, the characteristics of hybrid cells derived from oral cancer and endothelial cells and their involvement in cancer remained unknown. Double-immunofluorescent staining and fluorescent in situ hybridization (FISH) were performed to confirm spontaneous cell fusion between eGFP-labeled human umbilical vein endothelial cells (HUVECs) and RFP-labeled SCC9, and to detect the expression of vementin and cytokeratin 18 in the hybrids. The property of chemo-resistance of such hybrids was examined by TUNEL assay. The hybrid cells in xenografted tumor were identified by FISH and GFP/RFP dual-immunofluoresence staining. We showed that SCC9 cells spontaneously fused with cocultured endothelial cells, and the resultant hybrid cells maintained the division and proliferation activity after re-plating and thawing. Such hybrids expressed markers of both parental cells and became more resistant to chemotherapeutic drug cisplatin as compared to the parental SCC9 cells. Our in vivo data indicated that the hybrid cells contributed to tumor composition by using of immunostaining and FISH analysis, even though the hybrid cells and SCC9 cells were mixed with 1:10,000, according to the FACS data. Our study suggested that the fusion events between oral cancer and endothelial cells undergo nuclear fusion and acquire a new property of drug resistance and consequently enhanced survival potential. These experimental findings provide further supportive evidence for the theory that cell fusion is involved in cancer progression. - Highlights: • The fusion events between oral cancer and endothelial cells undergo nuclear fusion. • The resulting hybrid cells acquire a new property of drug resistance. • The resulting hybrid cells express the markers of both parental cells (i.e. vimentin and cytokeratin 18). • The hybrid cells contribute to tumor repopulation in vivo.

  3. SU-E-T-427: Cell Surviving Fractions Derived From Tumor-Volume Variation During Radiotherapy for Non-Small Cell Lung Cancer: Comparison with Predictive Assays

    Chvetsov, A; Schwartz, J; Mayr, N; Yartsev, S

    2014-01-01

    Purpose: To show that a distribution of cell surviving fractions S 2 in a heterogeneous group of patients can be derived from tumor-volume variation curves during radiotherapy for non-small cell lung cancer. Methods: Our analysis was based on two data sets of tumor-volume variation curves for heterogeneous groups of 17 patients treated for nonsmall cell lung cancer with conventional dose fractionation. The data sets were obtained previously at two independent institutions by using megavoltage (MV) computed tomography (CT). Statistical distributions of cell surviving fractions S 2 and cell clearance half-lives of lethally damaged cells T1/2 have been reconstructed in each patient group by using a version of the two-level cell population tumor response model and a simulated annealing algorithm. The reconstructed statistical distributions of the cell surviving fractions have been compared to the distributions measured using predictive assays in vitro. Results: Non-small cell lung cancer presents certain difficulties for modeling surviving fractions using tumor-volume variation curves because of relatively large fractional hypoxic volume, low gradient of tumor-volume response, and possible uncertainties due to breathing motion. Despite these difficulties, cell surviving fractions S 2 for non-small cell lung cancer derived from tumor-volume variation measured at different institutions have similar probability density functions (PDFs) with mean values of 0.30 and 0.43 and standard deviations of 0.13 and 0.18, respectively. The PDFs for cell surviving fractions S 2 reconstructed from tumor volume variation agree with the PDF measured in vitro. Comparison of the reconstructed cell surviving fractions with patient survival data shows that the patient survival time decreases as the cell surviving fraction increases. Conclusion: The data obtained in this work suggests that the cell surviving fractions S 2 can be reconstructed from the tumor volume variation curves measured

  4. Molecular and Microenvironmental Determinants of Glioma Stem-Like Cell Survival and Invasion

    Alison Roos

    2017-06-01

    Full Text Available Glioblastoma multiforme (GBM is the most frequent primary brain tumor in adults with a 5-year survival rate of 5% despite intensive research efforts. The poor prognosis is due, in part, to aggressive invasion into the surrounding brain parenchyma. Invasion is a complex process mediated by cell-intrinsic pathways, extrinsic microenvironmental cues, and biophysical cues from the peritumoral stromal matrix. Recent data have attributed GBM invasion to the glioma stem-like cell (GSC subpopulation. GSCs are slowly dividing, highly invasive, therapy resistant, and are considered to give rise to tumor recurrence. GSCs are localized in a heterogeneous cellular niche, and cross talk between stromal cells and GSCs cultivates a fertile environment that promotes GSC invasion. Pro-migratory soluble factors from endothelial cells, astrocytes, macrophages, microglia, and non-stem-like tumor cells can stimulate peritumoral invasion of GSCs. Therefore, therapeutic efforts designed to target the invasive GSCs may enhance patient survival. In this review, we summarize the current understanding of extrinsic pathways and major stromal and immune players facilitating GSC maintenance and survival.

  5. Activated H-Ras regulates hematopoietic cell survival by modulating Survivin

    Fukuda, Seiji; Pelus, Louis M.

    2004-01-01

    Survivin expression and Ras activation are regulated by hematopoietic growth factors. We investigated whether activated Ras could circumvent growth factor-regulated Survivin expression and if a Ras/Survivin axis mediates growth factor independent survival and proliferation in hematopoietic cells. Survivin expression is up-regulated by IL-3 in Ba/F3 and CD34 + cells and inhibited by the Ras inhibitor, farnesylthiosalicylic acid. Over-expression of constitutively activated H-Ras (CA-Ras) in Ba/F3 cells blocked down-modulation of Survivin expression, G 0 /G 1 arrest, and apoptosis induced by IL-3 withdrawal, while dominant-negative (DN) H-Ras down-regulated Survivin. Survivin disruption by DN T34A Survivin blocked CA-Ras-induced IL-3-independent cell survival and proliferation; however, it did not affect CA-Ras-mediated enhancement of S-phase, indicating that the anti-apoptotic activity of CA-Ras is Survivin dependent while its S-phase enhancing effect is not. These results indicate that CA-Ras modulates Survivin expression independent of hematopoietic growth factors and that a CA-Ras/Survivin axis regulates survival and proliferation of transformed hematopoietic cells

  6. Stem cell factor expression after renal ischemia promotes tubular epithelial survival.

    Geurt Stokman

    Full Text Available BACKGROUND: Renal ischemia leads to apoptosis of tubular epithelial cells and results in decreased renal function. Tissue repair involves re-epithelialization of the tubular basement membrane. Survival of the tubular epithelium following ischemia is therefore important in the successful regeneration of renal tissue. The cytokine stem cell factor (SCF has been shown to protect the tubular epithelium against apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: In a mouse model for renal ischemia/reperfusion injury, we studied how expression of c-KIT on tubular epithelium and its ligand SCF protect cells against apoptosis. Administration of SCF specific antisense oligonucleotides significantly decreased specific staining of SCF following ischemia. Reduced SCF expression resulted in impaired renal function, increased tubular damage and increased tubular epithelial apoptosis, independent of inflammation. In an in vitro hypoxia model, stimulation of tubular epithelial cells with SCF activated survival signaling and decreased apoptosis. CONCLUSIONS/SIGNIFICANCE: Our data indicate an important role for c-KIT and SCF in mediating tubular epithelial cell survival via an autocrine pathway.

  7. Macrophages improve survival, proliferation and migration of engrafted myogenic precursor cells into MDX skeletal muscle.

    Pierre-François Lesault

    Full Text Available Transplantation of muscle precursor cells is of therapeutic interest for focal skeletal muscular diseases. However, major limitations of cell transplantation are the poor survival, expansion and migration of the injected cells. The massive and early death of transplanted myoblasts is not fully understood although several mechanisms have been suggested. Various attempts have been made to improve their survival or migration. Taking into account that muscle regeneration is associated with the presence of macrophages, which are helpful in repairing the muscle by both cleansing the debris and deliver trophic cues to myoblasts in a sequential way, we attempted in the present work to improve myoblast transplantation by coinjecting macrophages. The present data showed that in the 5 days following the transplantation, macrophages efficiently improved: i myoblast survival by limiting their massive death, ii myoblast expansion within the tissue and iii myoblast migration in the dystrophic muscle. This was confirmed by in vitro analyses showing that macrophages stimulated myoblast adhesion and migration. As a result, myoblast contribution to regenerating host myofibres was increased by macrophages one month after transplantation. Altogether, these data demonstrate that macrophages are beneficial during the early steps of myoblast transplantation into skeletal muscle, showing that coinjecting these stromal cells may be used as a helper to improve the efficiency of parenchymal cell engraftment.

  8. Survival and photoreactivability of ultraviolet-irradiated cultured fish cells (CAF-MM1)

    Mano, Y.; Mitani, H.; Etoh, H.; Egami, N.

    1980-01-01

    The sensitivity to ultraviolet light (uv) and photoreactivating ability of cultured fish clone cells (CAF-MM1) were investigated. Dose-survival relationship curves were obtained using the colony-forming technique at various postirradiation temperatures (33, 26, and 20 0 C). At 26 0 C the values of D 0 , D/sub q/, and the extrapolation number (n) were 1.74 J/m 2 , 2.62 J/m 2 , and 4.5, respectively; no marked differences in these values were found among different temperatures. Visible light illumination after uv irradiation produced a marked increase in survival. No photoreactivation effects were observed beyond about 30 h. Caffeine increased uv sensitivity of the CAF-MM1 cells, and from the results it is suggested that the cells have some caffeine-sensitive dark repair mechanisms

  9. Metabolic activity is necessary for activation of T suppressor cells by B cells

    Elkins, K.L.; Stashak, P.W.; Baker, P.J.

    1990-01-01

    Ag-primed B cells must express cell-surface IgM, but not IgD or Ia Ag, and must remain metabolically active, in order to activate suppressor T cells (Ts) specific for type III pneumococcal polysaccharide. Ag-primed B cells that were gamma-irradiated with 1000r, or less, retained the ability to activate Ts; however, Ag-primed B cells exposed to UV light were not able to do so. gamma-Irradiated and UV-treated Ag-primed B cells both expressed comparable levels of cell-surface IgM, and both localized to the spleen after in vivo transfer; neither could proliferate in vitro in response to mitogens. By contrast, gamma-irradiated primed B cells were still able to synthesize proteins, whereas UV-treated primed B cells could not. These findings suggest that in order for Ag-primed B cells to activate Ts, they must (a) express cell-associated IgM (sIgM) antibody bearing the idiotypic determinants of antibody specific for type III pneumococcal polysaccharide, and (b) be able to synthesize protein for either the continued expression of sIgM after cell transfer, or for the elaboration of another protein molecule that is also required for the activation of Ts; this molecule does not appear to be Ia Ag

  10. Hypoxia-activated prodrug TH-302 decreased survival rate of canine lymphoma cells under hypoxic condition.

    Yamazaki, Hiroki; Lai, Yu-Chang; Tateno, Morihiro; Setoguchi, Asuka; Goto-Koshino, Yuko; Endo, Yasuyuki; Nakaichi, Munekazu; Tsujimoto, Hajime; Miura, Naoki

    2017-01-01

    We tested the hypotheses that hypoxic stimulation enhances growth potentials of canine lymphoma cells by activating hypoxia-inducible factor 1α (HIF-1α), and that the hypoxia-activated prodrug (TH-302) inhibits growth potentials in the cells. We investigated how hypoxic culture affects the growth rate, chemoresistance, and invasiveness of canine lymphoma cells and doxorubicin (DOX)-resistant lymphoma cells, and influences of TH-302 on survival rate of the cells under hypoxic conditions. Our results demonstrated that hypoxic culture upregulated the expression of HIF-1α and its target genes, including ATP-binding cassette transporter B1 (ABCB1), ATP-binding cassette transporter G2 (ABCG2), platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and survivin, and enhanced the growth rate, DOX resistance, and invasiveness of the cells. Additionally, TH-302 decreased the survival rate of the cells under hypoxic condition. Our studies suggest that hypoxic stimulation may advance the tumorigenicity of canine lymphoma cells, favoring malignant transformation. Therefore, the data presented may contribute to the development of TH-302-based hypoxia-targeting therapies for canine lymphoma.

  11. Leucine metabolism in regulation of insulin secretion from pancreatic beta cells

    Yang, Jichun; Chi, Yujing; Burkhardt, Brant R.; Guan, Youfei; Wolf, Bryan A

    2010-01-01

    Leucine, a the branched-chain amino acids that must be supplied in daily diet, plays an important role in controlling protein synthesis and regulating cell metabolism in various cell types. In pancreatic β cells, leucine acutely stimulates insulin secretion by serving as both metabolic fuel and allosteric activator of glutamate dehydrogenase to enhance glutaminolysis. Leucine has also been shown to regulate gene transcription and protein synthesis in pancreatic islet β cells via both mTOR-dep...

  12. Effects of alpha-particles on survival and chromosomal aberrations in human mammary epithelial cells

    Durante, M.; Grossi, G. F.; Gialanella, G.; Pugliese, M.; Nappo, M.; Yang, T. C.

    1995-01-01

    We have studied the radiation responses of a human mammary epithelial cell line, H184B5 F5-1 M/10. This cell line was derived from primary mammary cells after treatment with chemicals and heavy ions. The F5-1 M/10 cells are immortal, density-inhibited in growth, and non-tumorigenic in athymic nude mice and represent an in vitro model of the human epithelium for radiation studies. Because epithelial cells are the target of alpha-particles emitted from radon daughters, we concentrated our studies on the efficiency of alpha-particles. Confluent cultures of M/10 cells were exposed to accelerated alpha-particles [beam energy incident at the cell monolayer = 3.85 MeV, incident linear energy transfer (LET) in cell = 109 keV/microns] and, for comparison, to 80 kVp x-rays. The following endpoints were studied: (1) survival, (2) chromosome aberrations at the first postirradiation mitosis, and (3) chromosome alterations at later passages following irradiation. The survival curve was exponential for alpha-particles (D0 = 0.73 +/- 0.04 Gy), while a shoulder was observed for x-rays (alpha/beta = 2.9 Gy; D0 = 2.5 Gy, extrapolation number 1.6). The relative biological effectiveness (RBE) of high-LET alpha-particles for human epithelial cell killing was 3.3 at 37% survival. Dose-response curves for the induction of chromosome aberrations were linear for alpha-particles and linearquadratic for x-rays. The RBE for the induction of chromosome aberrations varied with the type of aberration scored and was high (about 5) for chromosome breaks and low (about 2) for chromosome exchanges.(ABSTRACT TRUNCATED AT 250 WORDS).

  13. Epidemiological-molecular evidence of metabolic reprogramming on proliferation, autophagy and cell signaling in pancreas cancer.

    Søreide, Kjetil; Sund, Malin

    2015-01-28

    Pancreatic cancer remains one of the deadliest human cancers with little progress made in survival over the past decades, and 5-year survival usually below 5%. Despite this dismal scenario, progresses have been made in understanding of the underlying tumor biology through among other definition of precursor lesions, delineation of molecular pathways, and advances in genome-wide technology. Further, exploring the relationship between epidemiological risk factors involving metabolic features to that of an alter