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Sample records for cell survival

  1. Computational Modeling of Cell Survival Using VHDL

    Directory of Open Access Journals (Sweden)

    Shruti Jain1,

    2010-01-01

    Full Text Available The model for cell survival has been implemented using VeryHigh Speed Integrated Circuit Hardware DescriptionLanguage (VHDL (Xilinx Tool taking three input signals:Tumor necrosis factor-α (TNF, Epidermal growth factor(EGF and Insulin. Cell survival has been regulated by theinteraction of five proteins viz P13K, TNFR1, EGFR, IRS andIKK in a network. In the absence of any one, in protein networkleads to cell death. For the EGF input signal the proteins likeMEK, ERK, AkT, Rac & JNK have been important forregulation of cell survival. Similarly for TNF and Insulin inputsignal proteins like NFκB, AkT, XIAP, JNK, MAP3K & MK2and MEK, ERK, AkT, Rac, mTOR & JNK respectively havebeen important for regulation of cell survival.

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

    DEFF Research Database (Denmark)

    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....

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

    Science.gov (United States)

    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.

  4. Conditional survival predictions after nephrectomy for renal cell carcinoma.

    NARCIS (Netherlands)

    Karakiewicz, P.I.; Suardi, N.; Capitanio, U.; Isbarn, H.; Jeldres, C.; Perrotte, P.; Sun, M.; Ficarra, V.; Zigeuner, R.; Tostain, J.; Mejean, A.; Cindolo, L.; Pantuck, A.J.; Belldegrun, A.S.; Zini, L.; Taille, A. De La; Chautard, D.; Descotes, J.L.; Shariat, S.F.; Valeri, A.; Mulders, P.F.A.; Lang, H.; Lechevallier, E.; Patard, J.J.

    2009-01-01

    PURPOSE: Conditional survival implies that on average long-term cancer survivors have a better prognosis than do newly diagnosed individuals. We explored the effect of conditional survival in renal cell carcinoma. MATERIALS AND METHODS: We studied 3,560 patients with renal cell carcinoma of all stag

  5. A track-event theory of cell survival

    Energy Technology Data Exchange (ETDEWEB)

    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 survival in a simulated Mars environment

    Science.gov (United States)

    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

  7. Properties of lewis lung carcinoma cells surviving curcumin toxicity.

    Science.gov (United States)

    Yan, Dejun; Geusz, Michael E; Jamasbi, Roudabeh J

    2012-01-01

    The anti-inflammatory agent curcumin can selectively eliminate malignant rather than normal cells. The present study examined the effects of curcumin on the Lewis lung carcinoma (LLC) cell line and characterized a subpopulation surviving curcumin treatments. Cell density was measured after curcumin was applied at concentrations between 10 and 60 μM for 30 hours. Because of the high cell loss at 60 μM, this dose was chosen to select for surviving cells that were then used to establish a new cell line. The resulting line had approximately 20% slower growth than the original LLC cell line and based on ELISA contained less of two markers, NF-κB and ALDH1A, used to identify more aggressive cancer cells. We also injected cells from the original and surviving lines subcutaneously into syngeneic C57BL/6 mice and monitored tumor development over three weeks and found that the curcumin surviving-line remained tumorigenic. Because curcumin has been reported to kill cancer cells more effectively when administered with light, we examined this as a possible way of enhancing the efficacy of curcumin against LLC cells. When LLC cells were exposed to curcumin and light from a fluorescent lamp source, cell loss caused by 20 μM curcumin was enhanced by about 50%, supporting a therapeutic use of curcumin in combination with white light. This study is the first to characterize a curcumin-surviving subpopulation among lung cancer cells. It shows that curcumin at a high concentration either selects for an intrinsically less aggressive cell subpopulation or generates these cells. The findings further support a role for curcumin as an adjunct to traditional chemical or radiation therapy of lung and other cancers.

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

    Science.gov (United States)

    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.

  9. Cell Biology: ERADicating Survival with BOK.

    Science.gov (United States)

    Chipuk, Jerry Edward; Luna-Vargas, Mark P

    2016-06-01

    Mechanistic insights into the function of the pro-apoptotic BCL-2 family member BOK have remained elusive. A recent study shows that healthy cells constitutively degrade BOK via the ER-associated degradation and ubiquitin-proteasome pathways; following proteasome inhibition, BOK is stabilized to initiate a unique pro-apoptotic death program.

  10. Illicit survival of cancer cells during polyploidization and depolyploidization.

    Science.gov (United States)

    Vitale, I; Galluzzi, L; Senovilla, L; Criollo, A; Jemaà, M; Castedo, M; Kroemer, G

    2011-09-01

    Tetraploidy and the depolyploidization of tetraploid cells may contribute to oncogenesis. Several mechanisms have evolved to avoid the generation, survival, proliferation and depolyploidization of tetraploids. Cells that illicitly survive these checkpoints are prone to chromosomal instability and aneuploidization. Along with their replication, tetraploids constantly undergo chromosomal rearrangements that eventually lead to pseudodiploidy by two non-exclusive mechanisms: (i) multipolar divisions and (ii) illicit bipolar divisions in the presence of improper microtubule-kinetochore attachments. Here, we describe the regulation and the molecular mechanisms that underlie such a 'polyploidization-depolyploidization' cascade, while focusing on the role of oncogenes and tumor suppressor genes in tetraploidy-driven tumorigenesis. We speculate that the identification of signaling/metabolic cascades that are required for the survival of tetraploid or aneuploid (but not diploid) cancer cells may pave the way for the development of novel broad-spectrum anticancer agents.

  11. Homeostatic responses by surviving cortical pyramidal cells in neurodegenerative tauopathy.

    Science.gov (United States)

    Crimins, Johanna L; Rocher, Anne B; Peters, Alan; Shultz, Penny; Lewis, Jada; Luebke, Jennifer I

    2011-11-01

    Cortical neuron death is prevalent by 9 months in rTg(tau(P301L))4510 tau mutant mice (TG) and surviving pyramidal cells exhibit dendritic regression and spine loss. We used whole-cell patch-clamp recordings to investigate the impact of these marked structural changes on spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs) of layer 3 pyramidal cells in frontal cortical slices from behaviorally characterized TG and non-transgenic (NT) mice at this age. Frontal lobe function of TG mice was intact following a short delay interval but impaired following a long delay interval in an object recognition test, and cortical atrophy and cell loss were pronounced. Surviving TG cells had significantly reduced dendritic diameters, total spine density, and mushroom spines, yet sEPSCs were increased and sIPSCs were unchanged in frequency. Thus, despite significant regressive structural changes, synaptic responses were not reduced in TG cells, indicating that homeostatic compensatory mechanisms occur during progressive tauopathy. Consistent with this idea, surviving TG cells were more intrinsically excitable than NT cells, and exhibited sprouting of filopodia and axonal boutons. Moreover, the neuropil in TG mice showed an increased density of asymmetric synapses, although their mean size was reduced. Taken together, these data indicate that during progressive tauopathy, cortical pyramidal cells compensate for loss of afferent input by increased excitability and establishment of new synapses. These compensatory homeostatic mechanisms may play an important role in slowing the progression of neuronal network dysfunction during neurodegenerative tauopathies.

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

    Directory of Open Access Journals (Sweden)

    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

  13. CD84 is a survival receptor for CLL cells.

    Science.gov (United States)

    Binsky-Ehrenreich, I; Marom, A; Sobotta, M C; Shvidel, L; Berrebi, A; Hazan-Halevy, I; Kay, S; Aloshin, A; Sagi, I; Goldenberg, D M; Leng, L; Bucala, R; Herishanu, Y; Haran, M; Shachar, I

    2014-02-20

    Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of CD5+ B lymphocytes in peripheral blood, lymphoid organs and bone marrow. The main feature of the disease is accumulation of the malignant cells due to decreased apoptosis. CD84 belongs to the signaling lymphocyte activating molecule family of immunoreceptors, and has an unknown function in CLL cells. Here, we show that the expression of CD84 is significantly elevated from the early stages of the disease, and is regulated by macrophage migration inhibitory factor and its receptor, CD74. Activation of cell surface CD84 initiates a signaling cascade that enhances CLL cell survival. Both downmodulation of CD84 expression and its immune-mediated blockade induce cell death in vitro and in vivo. In addition, analysis of samples derived from an on-going clinical trial, in which human subjects were treated with humanized anti-CD74 (milatuzumab), shows a decrease in CD84 messenger RNA and protein levels in milatuzumab-treated cells. This downregulation was correlated with reduction of Bcl-2 and Mcl-1 expression. Thus, our data show that overexpression of CD84 in CLL is an important survival mechanism that appears to be an early event in the pathogenesis of the disease. These findings suggest novel therapeutic strategies based on the blockade of this CD84-dependent survival pathway.

  14. Coniferyl Aldehyde Ameliorates Radiation Intestine Injury via Endothelial Cell Survival

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ye Ji; Jung, Myung Gu; Lee, Yoonjin; Lee, Haejune [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yunsil [Ewha Woman' s Univ., Seoul (Korea, Republic of); Ko, Younggyu [Korea Univ., Seoul (Korea, Republic of)

    2014-05-15

    Cancer treatments related gastrointestinal toxicity has also been recognized as a significant economic burden. Especially, extensive apoptosis of microvascular endothelial cell of the lamina propria is the primary lesion initiating intestinal radiation damage after abdominal radiation therapy. Coniferyl aldehyde (CA) is phenolic compounds isolated from cork stoppers, and one of the major pyrolysis products of lignin. Shi H. was support for the empirical use of CA as a medicinal food for cardiovascular diseases. CA has positive effect in broad way but there is no consequence in radiation induced intestine damage. Here, we investigate effect of CA on small intestine after abdominal IR to mice in this study. In this study, CA increased the survival rate in C3H mice against 13.5 Gy abdominal IR. We found CA protects small intestine via preventing endothelial cell apoptosis and enhancing their angiogenic activity. CA also showed protective effect on crypt cell survival. Endothelial cell survival may affect crypt cell protection against IR. From this data, we concluded that CA is effective for protection against abdominal radiation injury. CA could ameliorate side-effect of radiation therapy.

  15. Mast cell leukemia with prolonged survival on PKC412/midostaurin.

    Science.gov (United States)

    Xu, Xiangdong; Kreisel, Friederike H; Frater, John L; Hassan, Anjum

    2014-01-01

    Mast cell leukemia (MCL) is a rare and aggressive form of systemic mastocytosis. There are approximately 50 reported cases since 1950s. MCL is refractory to cytoreduction chemotherapy and the average survival is only six months. We report a MCL case in a 71 year-old woman with high tumor load at the initial presentation in 2005, who did not respond to either interleukin-2 or dasatinib therapy. After enrolled in a clinical trial of PKC412 (or Midostaurin) with a daily dose of 100 mg, the patient responded well to PKC412 and became transfusion independent in three months. Since then, her disease had been stably controlled. This is the first report of a high-tumor-load MCL case which achieved prolonged survival (101 months) by PKC 412. The 101-month overall survival is the longest among reported MCL cases in the English literature.

  16. Improved survival of children and adolescents with sickle cell disease.

    Science.gov (United States)

    Quinn, Charles T; Rogers, Zora R; McCavit, Timothy L; Buchanan, George R

    2010-04-29

    The survival of young children with sickle cell disease (SCD) has improved, but less is known about older children and adolescents. We studied the Dallas Newborn Cohort (DNC) to estimate contemporary 18-year survival for newborns with SCD and document changes in the causes and ages of death over time. We also explored whether improvements in the quality of medical care were temporally associated with survival. The DNC now includes 940 subjects with 8857 patient-years of follow-up. Most children with sickle cell anemia (93.9%) and nearly all children with milder forms of SCD (98.4%) now live to become adults. The incidence of death and the pattern of mortality changed over the duration of the cohort. Sepsis is no longer the leading cause of death. All the recent deaths in the cohort occurred in patients 18 years or older, most shortly after the transition to adult care. Quality of care in the DNC has improved over time, with significantly more timely initial visits and preventive interventions for young children. In summary, most children with SCD now survive the childhood years, but young adults who transition to adult medical care are at high risk for early death.

  17. Pharmacologically active microcarriers for endothelial progenitor cell support and survival.

    Science.gov (United States)

    Musilli, Claudia; Karam, Jean-Pierre; Paccosi, Sara; Muscari, Claudio; Mugelli, Alessandro; Montero-Menei, Claudia N; Parenti, Astrid

    2012-08-01

    The regenerative potential of endothelial progenitor cell (EPC)-based therapies is limited due to poor cell viability and minimal retention following application. Neovascularization can be improved by means of scaffolds supporting EPCs. The aim of the present study was to investigate whether human early EPCs (eEPCs) could be efficiently cultured on pharmacologically active microcarriers (PAMs), made with poly(d,l-lactic-coglycolic acid) and coated with adhesion/extracellular matrix molecules. They may serve as a support for stem cells and may be used as cell carriers providing a controlled delivery of active protein such as the angiogenic factor, vascular endothelial growth factor-A (VEGF-A). eEPC adhesion to fibronectin-coated PAMs (FN-PAMs) was assessed by means of microscopic evaluation and by means of Alamar blue assay. Phospho ERK(1/2) and PARP-1 expression was measured by means of Western blot to assess the survival effects of FN-PAMs releasing VEGF-A (FN-VEGF-PAMs). The Alamar blue assay or a modified Boyden chamber assay was employed to assess proliferative or migratory capacity, respectively. Our data indicate that eEPCs were able to adhere to empty FN-PAMs within a few hours. FN-VEGF-PAMs increased the ability of eEPCs to adhere to them and strongly supported endothelial-like phenotype and cell survival. Moreover, the release of VEGF-A by FN-PAMs stimulated in vitro HUVEC migration and proliferation. These data strongly support the use of PAMs for supporting eEPC growth and survival and for stimulating resident mature human endothelial cells.

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

    Directory of Open Access Journals (Sweden)

    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. Bordetella pertussis entry into respiratory epithelial cells and intracellular survival.

    Science.gov (United States)

    Lamberti, Yanina; Gorgojo, Juan; Massillo, Cintia; Rodriguez, Maria E

    2013-12-01

    Bordetella pertussis is the causative agent of pertussis, aka whooping cough. Although generally considered an extracellular pathogen, this bacterium has been found inside respiratory epithelial cells, which might represent a survival strategy inside the host. Relatively little is known, however, about the mechanism of internalization and the fate of B. pertussis inside the epithelia. We show here that B. pertussis is able to enter those cells by a mechanism dependent on microtubule assembly, lipid raft integrity, and the activation of a tyrosine-kinase-mediated signaling. Once inside the cell, a significant proportion of the intracellular bacteria evade phagolysosomal fusion and remain viable in nonacidic lysosome-associated membrane-protein-1-negative compartments. In addition, intracellular B. pertussis was found able to repopulate the extracellular environment after complete elimination of the extracellular bacteria with polymyxin B. Taken together, these data suggest that B. pertussis is able to survive within respiratory epithelial cells and by this means potentially contribute to host immune system evasion.

  20. Starved epithelial cells uptake extracellular matrix for survival

    Science.gov (United States)

    Muranen, Taru; Iwanicki, Marcin P.; Curry, Natasha L.; Hwang, Julie; DuBois, Cory D.; Coloff, Jonathan L.; Hitchcock, Daniel S.; Clish, Clary B.; Brugge, Joan S.; Kalaany, Nada Y.

    2017-01-01

    Extracellular matrix adhesion is required for normal epithelial cell survival, nutrient uptake and metabolism. This requirement can be overcome by oncogene activation. Interestingly, inhibition of PI3K/mTOR leads to apoptosis of matrix-detached, but not matrix-attached cancer cells, suggesting that matrix-attached cells use alternate mechanisms to maintain nutrient supplies. Here we demonstrate that under conditions of dietary restriction or growth factor starvation, where PI3K/mTOR signalling is decreased, matrix-attached human mammary epithelial cells upregulate and internalize β4-integrin along with its matrix substrate, laminin. Endocytosed laminin localizes to lysosomes, results in increased intracellular levels of essential amino acids and enhanced mTORC1 signalling, preventing cell death. Moreover, we show that starved human fibroblasts secrete matrix proteins that maintain the growth of starved mammary epithelial cells contingent upon epithelial cell β4-integrin expression. Our study identifies a crosstalk between stromal fibroblasts and epithelial cells under starvation that could be exploited therapeutically to target tumours resistant to PI3K/mTOR inhibition. PMID:28071763

  1. Heat shock genes – integrating cell survival and death

    Indian Academy of Sciences (India)

    Richa Arya; Moushami Mallik; Subhash C Lakhotia

    2007-04-01

    Heat shock induced gene expression and other cellular responses help limit the damage caused by stress and thus facilitate cellular recovery. Cellular damage also triggers apoptotic cell death through several pathways. This paper briefly reviews interactions of the major heat shock proteins with components of the apoptotic pathways. Hsp90, which acts as a chaperone for unstable signal transducers to keep them poised for activation, interacts with RIP and Akt and promotes NF-B mediated inhibition of apoptosis; in addition it also blocks some steps in the apoptotic pathways. Hsp70 is mostly anti-apoptotic and acts at several levels like inhibition of translocation of Bax into mitochondria, release of cytochrome c from mitochondria, formation of apoptosome and inhibition of activation of initiator caspases. Hsp70 also modulates JNK, NF-B and Akt signaling pathways in the apoptotic cascade. In contrast, Hsp60 has both anti- and pro-apoptotic roles. Cytosolic Hsp60 prevents translocation of the pro-apoptotic protein Bax into mitochondria and thus promotes cell survival but it also promotes maturation of procaspase-3, essential for caspase mediated cell death. Our recent in vivo studies show that RNAi for the Hsp60D in Drosophila melanogaster prevents induced apoptosis. Hsp27 exerts its anti-apoptotic influence by inhibiting cytochrome c and TNF-mediated cell death. crystallin suppresses caspase-8 and cytochrome c mediated activation of caspase-3. Studies in our laboratory also reveal that absence or reduced levels of the developmentally active as well as stress induced non-coding hsr transcripts, which are known to sequester diverse hnRNPs and related nuclear RNA-binding proteins, block induced apoptosis in Drosophila. Modulation of the apoptotic pathways by Hsps reflects their roles as ``weak links” between various ``hubs” in cellular networks. On the other hand, non-coding RNAs, by virtue of their potential to bind with multiple proteins, can act as ``hubs” in

  2. Human mesenchymal stem cells promote survival of T cells in a quiescent state.

    Science.gov (United States)

    Benvenuto, Federica; Ferrari, Stefania; Gerdoni, Ezio; Gualandi, Francesca; Frassoni, Francesco; Pistoia, Vito; Mancardi, Gianluigi; Uccelli, Antonio

    2007-07-01

    Mesenchymal stem cells (MSC) are part of the bone marrow that provides signals supporting survival and growth of bystander hematopoietic stem cells (HSC). MSC modulate also the immune response, as they inhibit proliferation of lymphocytes. In order to investigate whether MSC can support survival of T cells, we investigated MSC capacity of rescuing T lymphocytes from cell death induced by different mechanisms. We observed that MSC prolong survival of unstimulated T cells and apoptosis-prone thymocytes cultured under starving conditions. MSC rescued T cells from activation induced cell death (AICD) by downregulation of Fas receptor and Fas ligand on T cell surface and inhibition of endogenous proteases involved in cell death. MSC dampened also Fas receptor mediated apoptosis of CD95 expressing Jurkat leukemic T cells. In contrast, rescue from AICD was not associated with a significant change of Bcl-2, an inhibitor of apoptosis induced by cell stress. Accordingly, MSC exhibited a minimal capacity of rescuing Jurkat cells from chemically induced apoptosis, a process disrupting the mitochondrial membrane potential regulated by Bcl-2. These results suggest that MSC interfere with the Fas receptor regulated process of programmed cell death. Overall, MSC can inhibit proliferation of activated T cells while supporting their survival in a quiescent state, providing a model of their activity inside the HSC niche. Disclosure of potential conflicts of interest is found at the end of this article.

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

    DEFF Research Database (Denmark)

    Maddika, S; Ande, SR; Panigrahi, S

    2007-01-01

    The partial cross-utilization of molecules and pathways involved in opposing processes like cell survival, proliferation and cell death, assures that mutations within one signaling cascade will also affect the other opposite process at least to some extent, thus contributing to homeostatic...... both for their apoptosis-regulating capacity and also for their effect on the cell cycle progression. The PI3-K/Akt cell survival pathway is shown as regulator of cell metabolism and cell survival, but examples are also provided where aberrant activity of the pathway may contribute to the induction...

  4. Regulation of cell survival and death during Flavivirus infections

    Institute of Scientific and Technical Information of China (English)

    Sounak; Ghosh; Roy; Beata; Sadigh; Emmanuel; Datan; Richard; A; Lockshin; Zahra; Zakeri

    2014-01-01

    Flaviviruses, ss(+) RNA viruses, include many of mankind’s most important pathogens. Their pathogenicity derives from their ability to infect many types of cells including neurons, to replicate, and eventually to kill the cells. Flaviviruses can activate tumor necrosis factor α and both intrinsic(Bax-mediated) and extrinsic pathways to apoptosis. Thus they can use many approaches for activating these pathways. Infection can lead to necrosis if viral load is extremely high or to other types of cell death if routes to apoptosis are blocked. Dengue and Japanese Encephalitis Virus can also activate autophagy. In this case the autophagy temporarily spares the infected cell, allowing a longer period of reproduction for the virus, and the autophagy further protects the cell against other stresses such as those caused by reactive oxygen species. Several of the viral proteins have been shown to induce apoptosis or autophagy on their own, independent of the presence of other viral proteins. Given the versatility of these viruses to adapt to and manipulate the metabolism, and thus to control the survival of, the infected cells, we need to understand much better how the specific viral proteins affect the pathways to apoptosis and autophagy. Only in this manner will we be able to minimize the pathology that they cause.

  5. PDK2-mediated alternative splicing switches Bnip3 from cell death to cell survival.

    Science.gov (United States)

    Gang, Hongying; Dhingra, Rimpy; Lin, Junjun; Hai, Yan; Aviv, Yaron; Margulets, Victoria; Hamedani, Mohammad; Thanasupawat, Thatchawan; Leygue, Etienne; Klonisch, Thomas; Davie, James R; Kirshenbaum, Lorrie A

    2015-09-28

    Herein we describe a novel survival pathway that operationally links alternative pre-mRNA splicing of the hypoxia-inducible death protein Bcl-2 19-kD interacting protein 3 (Bnip3) to the unique glycolytic phenotype in cancer cells. While a full-length Bnip3 protein (Bnip3FL) encoded by exons 1-6 was expressed as an isoform in normal cells and promoted cell death, a truncated spliced variant of Bnip3 mRNA deleted for exon 3 (Bnip3Δex3) was preferentially expressed in several human adenocarcinomas and promoted survival. Reciprocal inhibition of the Bnip3Δex3/Bnip3FL isoform ratio by inhibiting pyruvate dehydrogenase kinase isoform 2 (PDK2) in Panc-1 cells rapidly induced mitochondrial perturbations and cell death. The findings of the present study reveal a novel survival pathway that functionally couples the unique glycolytic phenotype in cancer cells to hypoxia resistance via a PDK2-dependent mechanism that switches Bnip3 from cell death to survival. Discovery of the survival Bnip3Δex3 isoform may fundamentally explain how certain cells resist Bnip3 and avert death during hypoxia.

  6. Measurement of posttransfusion red cell survival with the biotin label.

    Science.gov (United States)

    Mock, Donald M; Widness, John A; Veng-Pedersen, Peter; Strauss, Ronald G; Cancelas, Jose A; Cohen, Robert M; Lindsell, Christopher J; Franco, Robert S

    2014-07-01

    The goal of this review is to summarize and critically assess information concerning the biotin method to label red blood cells (RBC) for use in studies of RBC and transfusion biology-information that will prove useful to a broad audience of clinicians and scientists. A review of RBC biology, with emphasis on RBC senescence and in vivo survival, is included, followed by an analysis of the advantages and disadvantages of biotin-labeled RBC (BioRBC) for measuring circulating RBC volume, posttransfusion RBC recovery, RBC life span, and RBC age-dependent properties. The advantages of BioRBC over (51)Cr RBC labeling, the current reference method, are discussed. Because the biotin method is straightforward and robust, including the ability to follow the entire life spans of multiple RBC populations concurrently in the same subject, BioRBC offers distinct advantages for studying RBC biology and physiology, particularly RBC survival. The method for biotin labeling, validation of the method, and application of BioRBCs to studies of sickle cell disease, diabetes, and anemia of prematurity are reviewed. Studies documenting the safe use of BioRBC are reviewed; unanswered questions requiring future studies, remaining concerns, and regulatory barriers to broader application of BioRBC including adoption as a new reference method are also presented.

  7. Regulation of cell survival by Na+/H+ exchanger-1.

    Science.gov (United States)

    Schelling, Jeffrey R; Abu Jawdeh, Bassam G

    2008-09-01

    Na(+)/H(+) exchanger-1 (NHE1) is a ubiquitous plasma membrane Na(+)/H(+) exchanger typically associated with maintenance of intracellular volume and pH. In addition to the NHE1 role in electroneutral Na(+)/H(+) transport, in renal tubular epithelial cells in vitro the polybasic, juxtamembrane NHE1 cytosolic tail domain acts as a scaffold, by binding with ezrin/radixin/moesin (ERM) proteins and phosphatidylinositol 4,5-bisphosphate, which initiates formation of a signaling complex that culminates in Akt activation and opposition to initial apoptotic stress. With robust apoptotic stimuli renal tubular epithelial cell NHE1 is a caspase substrate, and proteolytic cleavage may permit progression to apoptotic cell death. In vivo, genetic or pharmacological NHE1 loss of function causes renal tubule epithelial cell apoptosis and renal dysfunction following streptozotocin-induced diabetes, ureteral obstruction, and adriamycin-induced podocyte toxicity. Taken together, substantial in vivo and in vitro data demonstrate that NHE1 regulates tubular epithelial cell survival. In contrast to connotations of NHE1 as an unimportant "housekeeping" protein, this review highlights that NHE1 activity is critical for countering tubular atrophy and chronic renal disease progression.

  8. Ras and Rheb Signaling in Survival and Cell Death

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Multifaceted role of prohibitin in cell survival and apoptosis.

    Science.gov (United States)

    Peng, Ya-Ting; Chen, Ping; Ouyang, Ruo-Yun; Song, Lei

    2015-09-01

    Human eukaryotic prohibitin (prohibitin-1 and prohibitin-2) is a membrane protein with different cellular localizations. It is involved in multiple cellular functions, including energy metabolism, proliferation, apoptosis, and senescence. The subcellular localization of prohibitin may determine its functions. Membrane prohibitin regulate the cellular signaling of membrane transport, nuclear prohibitin control transcription activation and the cell cycle, and mitochondrial prohibitin complex stabilize the mitochondrial genome and modulate mitochondrial dynamics, mitochondrial morphology, mitochondrial biogenesis, and the mitochondrial intrinsic apoptotic pathway. Moreover, prohibitin can translocates into the nucleus or the mitochondria under apoptotic signals and the subcellular shuttling of prohibitin is necessary for apoptosis process. Apoptosis is the process of programmed cell death that is important for the maintenance of normal physiological functions. Consequently, any alteration in the content, post-transcriptional modification (i.e. phosphorylation) or the nuclear or mitochondrial translocation of prohibitin may influence cell fate. Understanding the mechanisms of the expression and regulation of prohibitin may be useful for future research. This review provides an overview of the multifaceted and essential roles played by prohibitin in the regulation of cell survival and apoptosis.

  10. Survival of glucose phosphate isomerase null somatic cells and germ cells in adult mouse chimaeras.

    Science.gov (United States)

    Keighren, Margaret A; Flockhart, Jean H; West, John D

    2016-05-15

    The mouse Gpi1 gene encodes the glycolytic enzyme glucose phosphate isomerase. Homozygous Gpi1(-/-) null mouse embryos die but a previous study showed that some homozygous Gpi1(-/-) null cells survived when combined with wild-type cells in fetal chimaeras. One adult female Gpi1(-/-)↔Gpi1(c/c) chimaera with functional Gpi1(-/-) null oocytes was also identified in a preliminary study. The aims were to characterise the survival of Gpi1(-/-) null cells in adult Gpi1(-/-)↔Gpi1(c/c) chimaeras and determine if Gpi1(-/-) null germ cells are functional. Analysis of adult Gpi1(-/-)↔Gpi1(c/c) chimaeras with pigment and a reiterated transgenic lineage marker showed that low numbers of homozygous Gpi1(-/-) null cells could survive in many tissues of adult chimaeras, including oocytes. Breeding experiments confirmed that Gpi1(-/-) null oocytes in one female Gpi1(-/-)↔Gpi1(c/c) chimaera were functional and provided preliminary evidence that one male putative Gpi1(-/-)↔Gpi1(c/c) chimaera produced functional spermatozoa from homozygous Gpi1(-/-) null germ cells. Although the male chimaera was almost certainly Gpi1(-/-)↔Gpi1(c/c), this part of the study is considered preliminary because only blood was typed for GPI. Gpi1(-/-) null germ cells should survive in a chimaeric testis if they are supported by wild-type Sertoli cells. It is also feasible that spermatozoa could bypass a block at GPI, but not blocks at some later steps in glycolysis, by using fructose, rather than glucose, as the substrate for glycolysis. Although chimaera analysis proved inefficient for studying the fate of Gpi1(-/-) null germ cells, it successfully identified functional Gpi1(-/-) null oocytes and revealed that some Gpi1(-/-) null cells could survive in many adult tissues.

  11. Intrinsic Constraint on Plasmablast Growth and Extrinsic Limits of Plasma Cell Survival

    OpenAIRE

    2000-01-01

    B cells recruited into splenic antibody responses grow exponentially, either in extrafollicular foci as plasmablasts, or in follicles where they form germinal centers. Both responses yield plasma cells. Although many splenic plasma cells survive

  12. Cell death versus cell survival instructed by supramolecular cohesion of nanostructures

    Science.gov (United States)

    Newcomb, Christina J.; Sur, Shantanu; Ortony, Julia H.; Lee, One-Sun; Matson, John B.; Boekhoven, Job; Yu, Jeong Min; Schatz, George C.; Stupp, Samuel I.

    2014-02-01

    Many naturally occurring peptides containing cationic and hydrophobic domains have evolved to interact with mammalian cell membranes and have been incorporated into materials for non-viral gene delivery, cancer therapy or treatment of microbial infections. Their electrostatic attraction to the negatively charged cell surface and hydrophobic interactions with the membrane lipids enable intracellular delivery or cell lysis. Although the effects of hydrophobicity and cationic charge of soluble molecules on the cell membrane are well known, the interactions between materials with these molecular features and cells remain poorly understood. Here we report that varying the cohesive forces within nanofibres of supramolecular materials with nearly identical cationic and hydrophobic structure instruct cell death or cell survival. Weak intermolecular bonds promote cell death through disruption of lipid membranes, while materials reinforced by hydrogen bonds support cell viability. These findings provide new strategies to design biomaterials that interact with the cell membrane.

  13. Combined cisplatin and aurora inhibitor treatment increase neuroblastoma cell death but surviving cells overproduce BDNF.

    Science.gov (United States)

    Polacchini, Alessio; Albani, Clara; Baj, Gabriele; Colliva, Andrea; Carpinelli, Patrizia; Tongiorgi, Enrico

    2016-07-15

    Drug-resistance to chemotherapics in aggressive neuroblastoma (NB) is characterized by enhanced cell survival mediated by TrkB and its ligand, brain-derived neurotrophic factor (BDNF); thus reduction in BDNF levels represent a promising strategy to overcome drug-resistance, but how chemotherapics regulate BDNF is unknown. Here, cisplatin treatment in SK-N-BE neuroblastoma upregulated multiple BDNF transcripts, except exons 5 and 8 variants. Cisplatin increased BDNF mRNA and protein, and enhanced translation of a firefly reporter gene flanked by BDNF 5'UTR exons 1, 2c, 4 or 6 and 3'UTR-long. To block BDNF translation we focused on aurora kinases inhibitors which are proposed as new chemotherapeutics. NB cell survival after 24 h treatment was 43% with cisplatin, and 22% by cisplatin+aurora kinase inhibitor PHA-680632, while the aurora kinases inhibitor alone was less effective; however the combined treatment induced a paradoxical increase of BDNF in surviving cells with strong translational activation of exon6-3'UTR-long transcript, while translation of BDNF transcripts 1, 2C and 4 was suppressed. In conclusion, combined cisplatin and aurora kinase inhibitor treatment increases cell death, but induces BDNF overproduction in surviving cells through an aurora kinase-independent mechanism.

  14. Time-course regulation of quercetin on cell survival/proliferation pathways in human hepatoma cells.

    Science.gov (United States)

    Granado-Serrano, Ana Belén; Angeles Martín, María; Bravo, Laura; Goya, Luis; Ramos, Sonia

    2008-04-01

    Quercetin, a dietary flavonoid, has been shown to possess anticarcinogenic properties, but the precise molecular mechanisms of action are not thoroughly elucidated. This study was aimed at investigating the time-course regulation effect of quercetin on survival/proliferation pathways in a human hepatoma cell line (HepG2). Quercetin induced a significant time-dependent inactivation of the major survival signaling proteins, i. e., phosphatidylinositol 3-kinase (PI 3-kinase)/protein kinase B (AKT), extracellular regulated kinase (ERK), protein kinase C-alpha (PKC-alpha), in concert with a time-dependent activation of key death-related signals: c-jun amino-terminal kinase (JNK) and PKC-delta. These data suggest that quercetin exerts a tight regulation of survival/proliferation pathways that requires the integration of different signals and persists over time, being the balance of these regulatory signals what determines the fate of HepG2 cells.

  15. Tumor cell "dead or alive": caspase and survivin regulate cell death, cell cycle and cell survival.

    Science.gov (United States)

    Suzuki, A; Shiraki, K

    2001-04-01

    Cell death and cell cycle progression are two sides of the same coin, and these two different phenomenons are regulated moderately to maintain the cellular homeostasis. Tumor is one of the disease states produced as a result of the disintegrated regulation and is characterized as cells showing an irreversible progression of cell cycle and a resistance to cell death signaling. Several investigations have been performed for the understanding of cell death or cell cycle, and cell death research has remarkably progressed in these 10 years. Caspase is a nomenclature referring to ICE/CED-3 cysteine proteinase family and plays a central role during cell death. Recently, several investigations raised some possible hypotheses that caspase is also involved in cell cycle regulation. In this issue, therefore, we review the molecular basis of cell death and cell cycle regulated by caspase in tumor, especially hepatocellular carcinoma cells.

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

    DEFF Research Database (Denmark)

    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......, 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...... 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...

  17. The modulatory effects of connexin 43 on cell death/survival beyond cell coupling.

    Science.gov (United States)

    Rodríguez-Sinovas, Antonio; Cabestrero, Alberto; López, Diego; Torre, Iratxe; Morente, Miriam; Abellán, Arancha; Miró, Elisabet; Ruiz-Meana, Marisol; García-Dorado, David

    2007-01-01

    Connexins form a diverse and ubiquitous family of integral membrane proteins. Characteristically, connexins are assembled into intercellular channels that aggregate into discrete cell-cell contact areas termed gap junctions (GJ), allowing intercellular chemical communication, and are essential for propagation of electrical impulses in excitable tissues, including, prominently, myocardium, where connexin 43 (Cx43) is the most important isoform. Previous studies have shown that GJ-mediated communication has an important role in the cellular response to stress or ischemia. However, recent evidence suggests that connexins, and in particular Cx43, may have additional effects that may be important in cell death and survival by mechanisms independent of cell to cell communication. Connexin hemichannels, located at the plasma membrane, may be important in paracrine signaling that could influence intracellular calcium and cell survival by releasing intracellular mediators as ATP, NAD(+), or glutamate. In addition, recent studies have shown the presence of connexins in cell structures other than the plasma membrane, including the cell nucleus, where it has been suggested that Cx43 influences cell growth and differentiation. In addition, translocation of Cx43 to mitochondria appears to be important for certain forms of cardioprotection. These findings open a new field of research of previously unsuspected roles of Cx43 intracellular signaling.

  18. [A test for sperm cell survival in peritoneal fluid].

    Science.gov (United States)

    Radwan, J; Niwald, W; Bielak, A; Pawlicki, J; Banaszczyk, R; Makuła, D

    1995-06-01

    The role of the peritoneal fluid in the physiology of reproduction, as well as in the transportation and survival of gametes, is little known. The authors have examined interactions between spermatozoa and the peritoneal fluid, collected during laparoscopy in the, so-called, survival test, from 42 infertile couples. The studied survival of spermatozoa in the peritoneal fluid was relatively high--19% after 48 hours--longer than in Menezo B2 fluid. Values of the test have been indicated, especially in cases of endometriosis-caused and idiopathic infertility.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. HSP90 promotes Burkitt lymphoma cell survival by maintaining tonic B-cell receptor signaling.

    Science.gov (United States)

    Walter, Roland; Pan, Kuan-Ting; Doebele, Carmen; Comoglio, Federico; Tomska, Katarzyna; Bohnenberger, Hanibal; Young, Ryan M; Jacobs, Laura; Keller, Ulrich; Bönig, Halvard; Engelke, Michael; Rosenwald, Andreas; Urlaub, Henning; Staudt, Louis M; Serve, Hubert; Zenz, Thorsten; Oellerich, Thomas

    2017-02-02

    Burkitt lymphoma (BL) is an aggressive B-cell neoplasm that is currently treated by intensive chemotherapy in combination with anti-CD20 antibodies. Because of their toxicity, current treatment regimens are often not suitable for elderly patients or for patients in developing countries where BL is endemic. Targeted therapies for BL are therefore needed. In this study, we performed a compound screen in 17 BL cell lines to identify small molecule inhibitors affecting cell survival. We found that inhibitors of heat shock protein 90 (HSP90) induced apoptosis in BL cells in vitro at concentrations that did not affect normal B cells. By global proteomic and phosphoproteomic profiling, we show that, in BL, HSP90 inhibition compromises the activity of the pivotal B-cell antigen receptor (BCR)-proximal effector spleen tyrosine kinase (SYK), which we identified as an HSP90 client protein. Consistently, expression of constitutively active TEL-SYK counteracted the apoptotic effect of HSP90 inhibition. Together, our results demonstrate that HSP90 inhibition impairs BL cell survival by interfering with tonic BCR signaling, thus providing a molecular rationale for the use of HSP90 inhibitors in the treatment of BL.

  1. Monte Carlo based protocol for cell survival and tumour control probability in BNCT

    Science.gov (United States)

    Ye, Sung-Joon

    1999-02-01

    A mathematical model to calculate the theoretical cell survival probability (nominally, the cell survival fraction) is developed to evaluate preclinical treatment conditions for boron neutron capture therapy (BNCT). A treatment condition is characterized by the neutron beam spectra, single or bilateral exposure, and the choice of boron carrier drug (boronophenylalanine (BPA) or boron sulfhydryl hydride (BSH)). The cell survival probability defined from Poisson statistics is expressed with the cell-killing yield, the (n, ) reaction density, and the tolerable neutron fluence. The radiation transport calculation from the neutron source to tumours is carried out using Monte Carlo methods: (i) reactor-based BNCT facility modelling to yield the neutron beam library at an irradiation port; (ii) dosimetry to limit the neutron fluence below a tolerance dose (10.5 Gy-Eq); (iii) calculation of the (n, ) reaction density in tumours. A shallow surface tumour could be effectively treated by single exposure producing an average cell survival probability of - for probable ranges of the cell-killing yield for the two drugs, while a deep tumour will require bilateral exposure to achieve comparable cell kills at depth. With very pure epithermal beams eliminating thermal, low epithermal and fast neutrons, the cell survival can be decreased by factors of 2-10 compared with the unmodified neutron spectrum. A dominant effect of cell-killing yield on tumour cell survival demonstrates the importance of choice of boron carrier drug. However, these calculations do not indicate an unambiguous preference for one drug, due to the large overlap of tumour cell survival in the probable ranges of the cell-killing yield for the two drugs. The cell survival value averaged over a bulky tumour volume is used to predict the overall BNCT therapeutic efficacy, using a simple model of tumour control probability (TCP).

  2. Effect of Bcl-2 and Bax on survival of side population cells from hepatocellular carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To understand the role and significance of side population (SP) cells from hepatocellular carcinoma (HCC) in hepatocarcinogenesis, development, relapse and metastasis, we simulated the denutrition conditions that cancer cells experience in clinical therapy, observed the different anti-apoptosis ability of SP cells and non-SP cells under such conditions, and established the possible effects of P53, Bcl-2 and Bax on survival of SP cells.METHODS: We used flow cytometry to analyze and sort the SP and non-SP cells in established HCC lines MHCC97and hHCC. We evaluated cell proliferation by methyl thiazolyl tetrazolium (MTT) assay and investigated the expression of p53, bd-2 and bax genes during denutrition,by RT-PCR and immunofluorescence staining.RESULTS: The percentage of SP cells in the two established HCC lines was 0.25% and 0.5%, respectively.SP cells had greater anti-apoptosis and proliferation ability than non-SP cells. Expression of Bcl-2 and Bax in SP and non-SP cells differed during denutrition. The former was up-regulated in SP cells, and the latter was up-regulated in non-SP cells.CONCLUSION: It may be that different upstream molecules acted and led to different expression levels of Bcl-2 and Bax in these two cell lines. There was a direct relationship between up-regulation of Bcl-2 and down-regulation of Bax and higher anti-apoptosis ability in SP cells. It may be that the existence and activity of SP cells are partly responsible for some of the clinical phenomena which are seen in HCC, such as relapse or metastasis. Further research on SP cells may have potential applications in the field of anticancer therapy.

  3. Autophagy as a Survival Mechanism for Squamous Cell Carcinoma Cells in Endonuclease G-Mediated Apoptosis

    Science.gov (United States)

    Masui, Atsushi; Hamada, Masakazu; Kameyama, Hiroyasu; Wakabayashi, Ken; Takasu, Ayako; Imai, Tomoaki; Iwai, Soichi; Yura, Yoshiaki

    2016-01-01

    Safingol, L- threo-dihydrosphingosine, induces cell death in human oral squamous cell carcinoma (SCC) cells through an endonuclease G (endoG) -mediated pathway. We herein determined whether safingol induced apoptosis and autophagy in oral SCC cells. Safingol induced apoptotic cell death in oral SCC cells in a dose-dependent manner. In safingol-treated cells, microtubule-associated protein 1 light chain 3 (LC3)-I was changed to LC3-II and the cytoplasmic expression of LC3, amount of acidic vesicular organelles (AVOs) stained by acridine orange and autophagic vacuoles were increased, indicating the occurrence of autophagy. An inhibitor of autophagy, 3-methyladenine (3-MA), enhanced the suppressive effects of safingol on cell viability, and this was accompanied by an increase in the number of apoptotic cells and extent of nuclear fragmentation. The nuclear translocation of endoG was minimal at a low concentration of safingol, but markedly increased when combined with 3-MA. The suppressive effects of safingol and 3-MA on cell viability were reduced in endoG siRNA- transfected cells. The scavenging of reactive oxygen species (ROS) prevented cell death induced by the combinational treatment, whereas a pretreatment with a pan-caspase inhibitor z-VAD-fmk did not. These results indicated that safingol induced apoptosis and autophagy in SCC cells and that the suppression of autophagy by 3-MA enhanced apoptosis. Autophagy supports cell survival, but not cell death in the SCC cell system in which apoptosis occurs in an endoG-mediated manner. PMID:27658240

  4. Cell survival signalling through PPARδ and arachidonic acid metabolites in neuroblastoma.

    Directory of Open Access Journals (Sweden)

    Emma Bell

    Full Text Available Retinoic acid (RA has paradoxical effects on cancer cells: promoting cell death, differentiation and cell cycle arrest, or cell survival and proliferation. Arachidonic acid (AA release occurs in response to RA treatment and, therefore, AA and its downstream metabolites may be involved in cell survival signalling. To test this, we inhibited phospholipase A2-mediated AA release, cyclooxygenases and lipoxygenases with small-molecule inhibitors to determine if this would sensitise cells to cell death after RA treatment. The data suggest that, in response to RA, phospholipase A2-mediated release of AA and subsequent metabolism by lipoxygenases is important for cell survival. Evidence from gene expression reporter assays and PPARδ knockdown suggests that lipoxygenase metabolites activate PPARδ. The involvement of PPARδ in cell survival is supported by results of experiments with the PPARδ inhibitor GSK0660 and siRNA-mediated knockdown. Quantitative reverse transcriptase PCR studies demonstrated that inhibition of 5-lipoxygenase after RA treatment resulted in a strong up-regulation of mRNA for PPARδ2, a putative inhibitory PPARδ isoform. Over-expression of PPARδ2 using a tetracycline-inducible system in neuroblastoma cells reduced proliferation and induced cell death. These data provide evidence linking lipoxygenases and PPARδ in a cell survival-signalling mechanism and suggest new drug-development targets for malignant and hyper-proliferative diseases.

  5. Nonlinearity in MCF7 Cell Survival Following Exposure to Modulated 6 MV Radiation Fields

    Directory of Open Access Journals (Sweden)

    Laetitia Lacoste-Collin MD, PhD

    2015-10-01

    Full Text Available The study of cell survival following exposure to nonuniform radiation fields is taking on particular interest because of the increasing evidence of a nonlinear relationship at low doses. We conducted in vitro experiments using the MCF7 breast cancer cell line. A 2.4 × 2.4 cm2 square area of a T25 flask was irradiated by a Varian Novalis accelerator delivering 6 MV photons. Cell survival inside the irradiation field, in the dose gradient zone and in the peripheral zone, was determined using a clonogenic assay for different radiation doses at the isocenter. Increased cell survival was observed inside the irradiation area for doses of 2, 10, and 20 Gy when nonirradiated cells were present at the periphery, while the cells at the periphery showed decreased survival compared to controls. Increased survival was also observed at the edge of the dose gradient zone for cells receiving 0.02 to 0.01 Gy when compared with cells at the periphery of the same flask, whatever the isocenter dose. These data are the first to report cell survival in the dose gradient zone. Radiotherapists must be aware of this nonlinearity in dose response.

  6. Nonlinearity in MCF7 Cell Survival Following Exposure to Modulated 6 MV Radiation Fields

    Science.gov (United States)

    Castiella, Marion; Franceries, Xavier; Cassol, Emmanuelle; Vieillevigne, Laure; Pereda, Veronica; Bardies, Manuel; Courtade-Saïdi, Monique

    2015-01-01

    The study of cell survival following exposure to nonuniform radiation fields is taking on particular interest because of the increasing evidence of a nonlinear relationship at low doses. We conducted in vitro experiments using the MCF7 breast cancer cell line. A 2.4 × 2.4 cm2 square area of a T25 flask was irradiated by a Varian Novalis accelerator delivering 6 MV photons. Cell survival inside the irradiation field, in the dose gradient zone and in the peripheral zone, was determined using a clonogenic assay for different radiation doses at the isocenter. Increased cell survival was observed inside the irradiation area for doses of 2, 10, and 20 Gy when nonirradiated cells were present at the periphery, while the cells at the periphery showed decreased survival compared to controls. Increased survival was also observed at the edge of the dose gradient zone for cells receiving 0.02 to 0.01 Gy when compared with cells at the periphery of the same flask, whatever the isocenter dose. These data are the first to report cell survival in the dose gradient zone. Radiotherapists must be aware of this nonlinearity in dose response. PMID:26740805

  7. Track-event theory of cell survival with second-order repair.

    Science.gov (United States)

    Besserer, Jürgen; Schneider, Uwe

    2015-05-01

    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. It is assumed that a cell is killed by an event that is defined by two double-strand breaks on the same or different chromosomes. Two different mechanisms can produce events. A one-track event is always represented by two simultaneous double-strand breaks. A two-track event results in one double-strand break. Therefore, at least two two-track events on the same or different chromosomes are necessary to produce an event. It is assumed that two double-strand breaks can be repaired with a certain repair probability. Both the one-track events and the two-track events are statistically independent. From the stochastic nature of cell killing which is described by the Poisson distribution, the cell survival probability was derived. The model was fitted to experimental data. 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 as well as the LQ model and is based on two free parameters. 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 as well as the LQ model.

  8. Conditioned medium from activated spleen cells supports the survival of rat retinal cells in vitro

    Directory of Open Access Journals (Sweden)

    A. Sholl-Franco

    1997-11-01

    Full Text Available Cytokines are a heterogeneous group of molecules that have been associated with several functions in the nervous system, such as survival and differentiation of neuronal and glial cells. In the present study, we demonstrated that conditioned medium from spleen cells activated with concanavalin A increased neuritogenesis and survival of retinal cells, as measured by biochemical and morphological criteria. Our data showed that conditioned medium induced a five-fold increase in the amount of protein after 120 h in vitro. This effect was not inhibited by the blockade of voltage-dependent L-type calcium channels with 5.0 µM nifedipine. However, the use of an intracellular calcium chelator (15.0 µM BAPTA-AM inhibited this effect. Our results support the idea that factors secreted by activated lymphocytes, such as cytokines, can modulate the maintenance and the differentiation of rat retinal cells in vitro, indicating a possible role of these molecules in the development of retinal cells, as well as in its protection against pathological conditions

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

    LENUS (Irish Health Repository)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Regulatory T cell expressed MyD88 is critical for prolongation of allograft survival.

    Science.gov (United States)

    Borges, Christopher M; Reichenbach, Dawn K; Kim, Beom Seok; Misra, Aditya; Blazar, Bruce R; Turka, Laurence A

    2016-08-01

    MyD88 signaling directly promotes T-cell survival and is required for optimal T-cell responses to pathogens. To examine the role of T-cell-intrinsic MyD88 signals in transplantation, we studied mice with targeted T-cell-specific MyD88 deletion. Contrary to expectations, we found that these mice were relatively resistant to prolongation of graft survival with anti-CD154 plus rapamycin in a class II-mismatched system. To specifically examine the role of MyD88 in Tregs, we created a Treg-specific MyD88-deficient mouse. Transplant studies in these animals replicated the findings observed with a global T-cell MyD88 knockout. Surprisingly, given the role of MyD88 in conventional T-cell survival, we found no defect in the survival of MyD88-deficient Tregs in vitro or in the transplant recipients and also observed intact cell homing and expression of Treg effector molecules. MyD88-deficient Tregs also fail to protect allogeneic bone marrow transplant recipients from chronic graft-versus-host disease, confirming the observations of defective regulation seen in a solid organ transplant system. Together, our data define MyD88 as having a divergent requirement for cell survival in non-Tregs and Tregs, and a yet-to-be defined survival-independent requirement for Treg function during the response to alloantigen.

  12. Non-small cell lung cancer cell survival crucially depends on functional insulin receptors.

    Science.gov (United States)

    Frisch, Carolin Maria; Zimmermann, Katrin; Zilleßen, Pia; Pfeifer, Alexander; Racké, Kurt; Mayer, Peter

    2015-08-01

    Insulin plays an important role as a growth factor and its contribution to tumor proliferation is intensely discussed. It acts via the cognate insulin receptor (IR) but can also activate the IGF1 receptor (IGF1R). Apart from increasing proliferation, insulin might have additional effects in lung cancer. Therefore, we investigated insulin action and effects of IR knockdown (KD) in three (NCI-H292, NCI-H226 and NCI-H460) independent non-small cell lung cancer (NSCLC) cell lines. All lung cancer lines studied were found to express IR, albeit with marked differences in the ratio of the two variants IR-A and IR-B. Insulin activated the classical signaling pathway with IR autophosphorylation and Akt phosphorylation. Moreover, activation of MAPK was observed in H292 cells, accompanied by enhanced proliferation. Lentiviral shRNA IR KD caused strong decrease in survival of all three lines, indicating that the effects of insulin in lung cancer go beyond enhancing proliferation. Unspecific effects were ruled out by employing further shRNAs and different insulin-responsive cells (human pre-adipocytes) for comparison. Caspase assays demonstrated that IR KD strongly induced apoptosis in these lung cancer cells, providing the physiological basis of the rapid cell loss. In search for the underlying mechanism, we analyzed alterations in the gene expression profile in response to IR KD. A strong induction of certain cytokines (e.g. IL20 and tumour necrosis factor) became obvious and it turned out that these cytokines trigger apoptosis in the NSCLC cells tested. This indicates a novel role of IR in tumor cell survival via suppression of pro-apoptotic cytokines.

  13. Autophagy in response to photodynamic therapy: cell survival vs. cell death

    Science.gov (United States)

    Oleinick, Nancy L.; Xue, Liang-yan; Chiu, Song-mao; Joseph, Sheeba

    2009-02-01

    Autophagy (or more properly, macroautophagy) is a pathway whereby damaged organelles or other cell components are encased in a double membrane, the autophagosome, which fuses with lysosomes for digestion by lysosomal hydrolases. This process can promote cell survival by removing damaged organelles, but when damage is extensive, it can also be a mechanism of cell death. Similar to the Kessel and Agostinis laboratories, we have reported the vigorous induction of autophagy by PDT; this was found in human breast cancer MCF-7 cells whether or not they were able to efficiently induce apoptosis. One way to evaluate the role of autophagy in PDT-treated cells is to silence one of the essential genes in the pathway. Kessel and Reiners silenced the Atg7 gene of murine leukemia L1210 cells using inhibitory RNA and found sensitization to PDT-induced cell death at a low dose of PDT, implying that autophagy is protective when PDT damage is modest. We have examined the role of autophagy in an epithelium-derived cancer cell by comparing parental and Atg7-silenced MCF-7 cells to varying doses of PDT with the phthalocyanine photosensitizer Pc 4. In contrast to L1210 cells, autophagy-deficient MCF-7 cells were more resistant to the lethal effects of PDT, as judged by clonogenic assays. A possible explanation for the difference in outcome for L1210 vs. MCF-7 cells is the greatly reduced ability of the latter to undergo apoptosis, a deficiency that may convert autophagy into a cell-death process even at low PDT doses. Experiments to investigate the mechanism(s) responsible are in process.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Mi Young; Jang, Eun Yeong; Ryu, Tae Ho; Chung, Dong Min; Kim, Jin Hong; Kim, Jin Kyu [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2014-04-15

    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.

  15. Suofu Qin’s work on studies of cell survival signaling in cancer and epithelial cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Reactive oxygen species (ROS) encompass a variety of diverse chemical species including superoxide anions, hydrogen peroxide, hydroxyl radicals and peroxynitrite, which are mainly produced via mitochondrial oxidative metabolism, enzymatic reactions, and light-initiated lipid peroxidation. Over-production of ROS and/or decrease in the antioxidant capacity cause cells to undergo oxi- dative stress that damages cellular macromolecules such as proteins, lipids, and DNA. Oxidative stress is associated with ageing and the development of agerelated diseases such as cancer and age-related macular degeneration. ROS activate signaling pathways that promote cell survival or lead to cell death, depending on the source and site of ROS production, the specific ROS generated, the concentration and kinetics of ROS generation, and the cell types being challenged. However, how the nature and compartmentalization of ROS contribute to the pathogenesis of individual diseases is poorly understood. Consequently, it is crucial to gain a comprehensive understanding of the molecular bases of cell oxidative stress signaling, which will then provide novel therapeutic opportunities to interfere with disease progression via targeting specific signaling pathways.Currently, Dr. Qin’s work is focused on inflammatory and oxidative stress responses using the retinal pigment epithelial (RPE) cells as a model. The study of RPE cell inflammatory and oxidative stress responses has successfully led to a better understanding of RPE cell biology and identification of potential therapeutic targets.

  16. IL-15 Expression on RA Synovial Fibroblasts Promotes B Cell Survival

    Science.gov (United States)

    Benito-Miguel, Marta; García-Carmona, Yolanda; Balsa, Alejandro; Bautista-Caro, María-Belén; Arroyo-Villa, Irene; Cobo-Ibáñez, Tatiana; Bonilla-Hernán, María Gema; de Ayala, Carlos Pérez; Sánchez-Mateos, Paloma; Martín-Mola, Emilio; Miranda-Carús, María-Eugenia

    2012-01-01

    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. PMID:22792388

  17. Physical skill training increases the number of surviving new cells in the adult hippocampus.

    Science.gov (United States)

    Curlik, Daniel M; Maeng, Lisa Y; Agarwal, Prateek R; Shors, Tracey J

    2013-01-01

    The dentate gyrus is a major site of plasticity in the adult brain, giving rise to thousands of new neurons every day, through the process of adult neurogenesis. Although the majority of these cells die within two weeks of their birth, they can be rescued from death by various forms of learning. Successful acquisition of select types of associative and spatial memories increases the number of these cells that survive. Here, we investigated the possibility that an entirely different form of learning, physical skill learning, could rescue new hippocampal cells from death. To test this possibility, rats were trained with a physically-demanding and technically-difficult version of a rotarod procedure. Acquisition of the physical skill greatly increased the number of new hippocampal cells that survived. The number of surviving cells positively correlated with performance on the task. Only animals that successfully mastered the task retained the cells that would have otherwise died. Animals that failed to learn, and those that did not learn well did not retain any more cells than those that were untrained. Importantly, acute voluntary exercise in activity wheels did not increase the number of surviving cells. These data suggest that acquisition of a physical skill can increase the number of surviving hippocampal cells. Moreover, learning an easier version of the task did not increase cell survival. These results are consistent with previous reports revealing that learning only rescues new neurons from death when acquisition is sufficiently difficult to achieve. Finally, complete hippocampal lesions did not disrupt acquisition of this physical skill. Therefore, physical skill training that does not depend on the hippocampus can effectively increase the number of surviving cells in the adult hippocampus, the vast majority of which become mature neurons.

  18. Physical skill training increases the number of surviving new cells in the adult hippocampus.

    Directory of Open Access Journals (Sweden)

    Daniel M Curlik

    Full Text Available The dentate gyrus is a major site of plasticity in the adult brain, giving rise to thousands of new neurons every day, through the process of adult neurogenesis. Although the majority of these cells die within two weeks of their birth, they can be rescued from death by various forms of learning. Successful acquisition of select types of associative and spatial memories increases the number of these cells that survive. Here, we investigated the possibility that an entirely different form of learning, physical skill learning, could rescue new hippocampal cells from death. To test this possibility, rats were trained with a physically-demanding and technically-difficult version of a rotarod procedure. Acquisition of the physical skill greatly increased the number of new hippocampal cells that survived. The number of surviving cells positively correlated with performance on the task. Only animals that successfully mastered the task retained the cells that would have otherwise died. Animals that failed to learn, and those that did not learn well did not retain any more cells than those that were untrained. Importantly, acute voluntary exercise in activity wheels did not increase the number of surviving cells. These data suggest that acquisition of a physical skill can increase the number of surviving hippocampal cells. Moreover, learning an easier version of the task did not increase cell survival. These results are consistent with previous reports revealing that learning only rescues new neurons from death when acquisition is sufficiently difficult to achieve. Finally, complete hippocampal lesions did not disrupt acquisition of this physical skill. Therefore, physical skill training that does not depend on the hippocampus can effectively increase the number of surviving cells in the adult hippocampus, the vast majority of which become mature neurons.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Biphasic Dependence of Glioma Survival and Cell Migration on CD44 Expression Level.

    Science.gov (United States)

    Klank, Rebecca L; Decker Grunke, Stacy A; Bangasser, Benjamin L; Forster, Colleen L; Price, Matthew A; Odde, Thomas J; SantaCruz, Karen S; Rosenfeld, Steven S; Canoll, Peter; Turley, Eva A; McCarthy, James B; Ohlfest, John R; Odde, David J

    2017-01-03

    While several studies link the cell-surface marker CD44 to cancer progression, conflicting results show both positive and negative correlations with increased CD44 levels. Here, we demonstrate that the survival outcomes of genetically induced glioma-bearing mice and of high-grade human glioma patients are biphasically correlated with CD44 level, with the poorest outcomes occurring at intermediate levels. Furthermore, the high-CD44-expressing mesenchymal subtype exhibited a positive trend of survival with increased CD44 level. Mouse cell migration rates in ex vivo brain slice cultures were also biphasically associated with CD44 level, with maximal migration corresponding to minimal survival. Cell simulations suggest that cell-substrate adhesiveness is sufficient to explain this biphasic migration. More generally, these results highlight the potential importance of non-monotonic relationships between survival and biomarkers associated with cancer progression.

  1. Restoring KLF5 in esophageal squamous cell cancer cells activates the JNK pathway leading to apoptosis and reduced cell survival.

    Science.gov (United States)

    Tarapore, Rohinton S; Yang, Yizeng; Katz, Jonathan P

    2013-05-01

    Esophageal cancer is the eighth most common cancer in the world and has an extremely dismal prognosis, with a 5-year survival of less than 20%. Current treatment options are limited, and thus identifying new molecular targets and pathways is critical to derive novel therapies. Worldwide, more than 90% of esophageal cancers are esophageal squamous cell cancer (ESCC). Previously, we identified that Krüppel-like factor 5 (KLF5), a key transcriptional regulator normally expressed in esophageal squamous epithelial cells, is lost in human ESCC. To examine the effects of restoring KLF5 in ESCC, we transduced the human ESCC cell lines TE7 and TE15, both of which lack KLF5 expression, with retrovirus to express KLF5 upon doxycycline induction. When KLF5 was induced, ESCC cells demonstrated increased apoptosis and decreased viability, with up-regulation of the proapoptotic factor BAX. Interestingly, c-Jun N-terminal kinase (JNK) signaling, an important upstream mediator of proapoptotic pathways including BAX, was also activated following KLF5 induction. KLF5 activation of JNK signaling was mediated by KLF5 transactivation of two key upstream regulators of the JNK pathway, ASK1 and MKK4, and inhibition of JNK blocked apoptosis and normalized cell survival following KLF5 induction. Thus, restoring KLF5 in ESCC cells promotes apoptosis and decreases cell survival in a JNK-dependent manner, providing a potential therapeutic target for human ESCC.

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

    DEFF Research Database (Denmark)

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

    2006-01-01

    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...... was also significant at diagnosis, but 2 years after diagnosis only age had prognostic impact. Multivariate analysis of patients who survived > or = 3 years identified only age as a prognostic factor. CONCLUSION: For patients with DLBCL who have survived more than 1 year after diagnosis, the conditional......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...

  3. The regulation of erythrocyte survival and suicidal cell death

    OpenAIRE

    Föller, Michael

    2008-01-01

    The life span of erythrocytes is tightly regulated. Therefore, a mechanism is required to remove senescent or damaged erythrocytes without rupture of the cell membrane resulting in the release of hemoglobin which may impair kidney function. The mechanism of suicidal erythrocyte death is called eryptosis and shares similarities with apoptosis of nucleated cells such as exposure of phosphatidylserine at the cell surface, increase in cytosolic Ca2+ concentration, blebbing of the membrane, cell s...

  4. HSP70 mediates survival in apoptotic cells-Boolean network prediction and experimental validation.

    Science.gov (United States)

    Vasaikar, Suhas V; Ghosh, Sourish; Narain, Priyam; Basu, Anirban; Gomes, James

    2015-01-01

    Neuronal stress or injury results in the activation of proteins, which regulate the balance between survival and apoptosis. However, the complex mechanism of cell signaling involving cell death and survival, activated in response to cellular stress is not yet completely understood. To bring more clarity about these mechanisms, a Boolean network was constructed that represented the apoptotic pathway in neuronal cells. FasL and neurotrophic growth factor (NGF) were considered as inputs in the absence and presence of heat shock proteins known to shift the balance toward survival by rescuing pro-apoptotic cells. The probabilities of survival, DNA repair and apoptosis as cellular fates, in the presence of either the growth factor or FasL, revealed a survival bias encoded in the network. Boolean predictions tested by measuring the mRNA level of caspase-3, caspase-8, and BAX in neuronal Neuro2a (N2a) cell line with NGF and FasL as external input, showed positive correlation with the observed experimental results for survival and apoptotic states. It was observed that HSP70 contributed more toward rescuing cells from apoptosis in comparison to HSP27, HSP40, and HSP90. Overexpression of HSP70 in N2a transfected cells showed reversal of cellular fate from FasL-induced apoptosis to survival. Further, the pro-survival role of the proteins BCL2, IAP, cFLIP, and NFκB determined by vertex perturbation analysis was experimentally validated through protein inhibition experiments using EM20-25, Embelin and Wedelolactone, which resulted in 1.27-, 1.26-, and 1.46-fold increase in apoptosis of N2a cells. The existence of a one-to-one correspondence between cellular fates and attractor states shows that Boolean networks may be employed with confidence in qualitative analytical studies of biological networks.

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

    Science.gov (United States)

    Czub, J; Banaś, D; Błaszczyk, A; Braziewicz, J; Buraczewska, I; Choiński, J; Górak, U; Jaskóła, M; Korman, A; Lankoff, A; Lisowska, H; Łukaszek, A; Szefliński, Z; Wójcik, A

    2009-03-01

    Chinese hamster ovary CHO-K1 cells were exposed to high LET (12)C-beam (LET: 830 keV/microm) in the dose range of 0-6 Gy and to (60)Co irradiation and the RBE value was obtained. Effects of (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(2)/Y and the dispersion index (u) were determined. Overdispersion was significant (p<0.05) when the value of u exceeded 1.96.

  6. Prolonged Survival of Transplanted Osteoblastic Cells Does Not Directly Accelerate the Healing of Calvarial Bone Defects.

    Science.gov (United States)

    Kitami, Megumi; Kaku, Masaru; Rocabado, Juan Marcelo Rosales; Ida, Takako; Akiba, Nami; Uoshima, Katsumi

    2016-09-01

    Considering the increased interest in cell-based bone regeneration, it is necessary to reveal the fate of transplanted cells and their substantive roles in bone regeneration. The aim of this study was to analyze the fate of transplanted cells and the effect of osteogenic cell transplantation on calvarial bone defect healing. An anti-apoptotic protein, heat shock protein (HSP) 27, was overexpressed in osteoblasts. Then, the treated osteoblasts were transplanted to calvarial bone defect and their fate was analyzed to evaluate the significance of transplanted cell survival. Transient overexpression of Hsp27 rescued MC3T3-E1 osteoblastic cells from H2 O2 -induced apoptosis without affecting osteoblastic differentiation in culture. Transplantation of Hsp27-overexpressing cells, encapsulated in collagen gel, showed higher proliferative activity, and fewer apoptotic cells in comparison with control cells. After 4-week of transplantation, both control cell- and Hsp27 overexpressed cell-transplanted groups showed significantly higher new bone formation in comparison with cell-free gel-transplantation group. Interestingly, the prolonged survival of transplanted osteoblastic cells by Hsp27 did not provide additional effect on bone healing. The transplanted cells in collagen gel survived for up to 4-week but did not differentiate into bone-forming osteoblasts. In conclusion, cell-containing collagen gel accelerated calvarial bone defect healing in comparison with cell-free collagen gel. However, prolonged survival of transplanted cells by Hsp27 overexpression did not provide additional effect. These results strongly indicate that cell transplantation-based bone regeneration cannot be explained only by the increment of osteogenic cells. Further studies are needed to elucidate the practical roles of transplanted cells that will potentiate successful bone regeneration. J. Cell. Physiol. 231: 1974-1982, 2016. © 2016 Wiley Periodicals, Inc.

  7. Stanniocalcin 2 enhances mesenchymal stem cell survival by suppressing oxidative stress.

    Science.gov (United States)

    Kim, Pyung-Hwan; Na, Sang-Su; Lee, Bomnaerin; Kim, Joo-Hyun; Cho, Je-Yoel

    2015-12-01

    To overcome the disadvantages of stem cell-based cell therapy like low cell survival at the disease site, we used stanniocalcin 2 (STC2), a family of secreted glycoprotein hormones that function to inhibit apoptosis and oxidative damage and to induce proliferation. STC2 gene was transfected into two kinds of stem cells to prolong cell survival and protect the cells from the damage by oxidative stress. The stem cells expressing STC2 exhibited increased cell viability and improved cell survival as well as elevated expression of the pluripotency and self-renewal markers (Oct4 and Nanog) under sub-lethal oxidative conditions. Up-regulation of CDK2 and CDK4 and down-regulation of cell cycle inhibitors p16 and p21 were observed after the delivery of STC2. Furthermore, STC2 transduction activated pAKT and pERK 1/2 signal pathways. Taken together, the STC2 can be used to enhance cell survival and maintain long-term stemness in therapeutic use of stem cells.

  8. Survival of human embryonic stem cells implanted in the guinea pig auditory epithelium

    Science.gov (United States)

    Young Lee, Min; Hackelberg, Sandra; Green, Kari L.; Lunghamer, Kelly G.; Kurioka, Takaomi; Loomis, Benjamin R.; Swiderski, Donald L.; Duncan, R. Keith; Raphael, Yehoash

    2017-01-01

    Hair cells in the mature cochlea cannot spontaneously regenerate. One potential approach for restoring hair cells is stem cell therapy. However, when cells are transplanted into scala media (SM) of the cochlea, they promptly die due to the high potassium concentration. We previously described a method for conditioning the SM to make it more hospitable to implanted cells and showed that HeLa cells could survive for up to a week using this method. Here, we evaluated the survival of human embryonic stem cells (hESC) constitutively expressing GFP (H9 Cre-LoxP) in deaf guinea pig cochleae that were pre-conditioned to reduce potassium levels. GFP-positive cells could be detected in the cochlea for at least 7 days after the injection. The cells appeared spherical or irregularly shaped, and some were aggregated. Flushing SM with sodium caprate prior to transplantation resulted in a lower proportion of stem cells expressing the pluripotency marker Oct3/4 and increased cell survival. The data demonstrate that conditioning procedures aimed at transiently reducing the concentration of potassium in the SM facilitate survival of hESCs for at least one week. During this time window, additional procedures can be applied to initiate the differentiation of the implanted hESCs into new hair cells. PMID:28387239

  9. Early Natural Killer Cell Reconstitution Predicts Overall Survival in T Cell-Replete Allogeneic Hematopoietic Stem Cell Transplantation

    DEFF Research Database (Denmark)

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

    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, acute lymphoblastic leukemia, and myelodysplastic syndrome from 2005 to 2013. In multivariate analysis NK cell numbers...... on day 30 (NK30) > 150 cells/µL were independently associated with superior overall survival (hazard ratio, .79; 95% confidence interval, .66 to .95; P = .01). Cumulative incidence analyses showed that patients with NK30 > 150 cells/µL had significantly less transplant-related mortality (TRM), P = .01...

  10. TNFAIP3 promotes survival of CD4 T cells by restricting MTOR and promoting autophagy.

    Science.gov (United States)

    Matsuzawa, Yu; Oshima, Shigeru; Takahara, Masahiro; Maeyashiki, Chiaki; Nemoto, Yasuhiro; Kobayashi, Masanori; Nibe, Yoichi; Nozaki, Kengo; Nagaishi, Takashi; Okamoto, Ryuichi; Tsuchiya, Kiichiro; Nakamura, Tetsuya; Ma, Averil; Watanabe, Mamoru

    2015-01-01

    Autophagy plays important roles in metabolism, differentiation, and survival in T cells. TNFAIP3/A20 is a ubiquitin-editing enzyme that is thought to be a negative regulator of autophagy in cell lines. However, the role of TNFAIP3 in autophagy remains unclear. To determine whether TNFAIP3 regulates autophagy in CD4 T cells, we first analyzed Tnfaip3-deficient naïve CD4 T cells in vitro. We demonstrated that Tnfaip3-deficient CD4 T cells exhibited reduced MAP1LC3/LC3 (microtubule-associated protein 1 light chain 3) puncta formation, increased mitochondrial content, and exaggerated reactive oxygen species (ROS) production. These results indicate that TNFAIP3 promotes autophagy after T cell receptor (TCR) stimulation in CD4 T cells. We then investigated the mechanism by which TNFAIP3 promotes autophagy signaling. We found that TNFAIP3 bound to the MTOR (mechanistic target of rapamycin) complex and that Tnfaip3-deficient cells displayed enhanced ubiquitination of the MTOR complex and MTOR activity. To confirm the effects of enhanced MTOR activity in Tnfaip3-deficient cells, we analyzed cell survival following treatment with Torin1, an MTOR inhibitor. Tnfaip3-deficient CD4 T cells exhibited fewer cell numbers than the control cells in vitro and in vivo. In addition, the impaired survival of Tnfaip3-deficient cells was ameliorated with Torin1 treatment in vitro and in vivo. The effect of Torin1 was abolished by Atg5 deficiency. Thus, enhanced MTOR activity regulates the survival of Tnfaip3-deficient CD4 T cells. Taken together, our findings illustrate that TNFAIP3 restricts MTOR signaling and promotes autophagy, providing new insight into the manner in which MTOR and autophagy regulate survival in CD4 T cells.

  11. Gender Specific Mutation Incidence and Survival Associations in Clear Cell Renal Cell Carcinoma (CCRCC.

    Directory of Open Access Journals (Sweden)

    Christopher J Ricketts

    Full Text Available Renal cell carcinoma (RCC is diagnosed in >200,000 individuals worldwide each year, accounting for ~2% of all cancers, but the spread of this disease amongst genders is distinctly uneven. In the U.S. the male:female incidence ratio is approximately 2:1. A potential hypothesis is mutation spectra may differ between tumors dependent upon the gender of the patient, such as mutations of X chromosome encoded genes being more prevalent in male-derived tumors. Combined analysis of three recent large-scale clear cell renal cell carcinoma (CCRCC mutation sequencing projects identified a significantly increased mutation frequency of PBRM1 and the X chromosome encoded KDM5C in tumors from male patients and BAP1 in tumors from female patients. Mutation of BAP1 had previously been significantly associated with poorer overall survival; however, when stratified by gender, mutation of BAP1 only significantly affected overall survival in female patients. Mutation of chromatin remodeling genes alters gene regulation, but the overall effect of these alterations may also be modified by the presence of other gender specific factors. Thus, the combination of gender and mutation of a specific gene, such as BAP1, may have implications not only for prognosis but also for understanding the role of chromatin remodeling gene mutations in kidney cancer progression.

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

    Directory of Open Access Journals (Sweden)

    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. Dendritic Cells in Kidney Transplant Biopsy Samples Are Associated with T Cell Infiltration and Poor Allograft Survival.

    Science.gov (United States)

    Batal, Ibrahim; De Serres, Sacha A; Safa, Kassem; Bijol, Vanesa; Ueno, Takuya; Onozato, Maristela L; Iafrate, A John; Herter, Jan M; Lichtman, Andrew H; Mayadas, Tanya N; Guleria, Indira; Rennke, Helmut G; Najafian, Nader; Chandraker, Anil

    2015-12-01

    Progress in long-term renal allograft survival continues to lag behind the progress in short-term transplant outcomes. Dendritic cells are the most efficient antigen-presenting cells, but surprisingly little attention has been paid to their presence in transplanted kidneys. We used dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin as a marker of dendritic cells in 105 allograft biopsy samples from 105 kidney transplant recipients. High dendritic cell density was associated with poor allograft survival independent of clinical variables. Moreover, high dendritic cell density correlated with greater T cell proliferation and poor outcomes in patients with high total inflammation scores, including inflammation in areas of tubular atrophy. We then explored the association between dendritic cells and histologic variables associated with poor prognosis. Multivariate analysis revealed an independent association between the densities of dendritic cells and T cells. In biopsy samples with high dendritic cell density, electron microscopy showed direct physical contact between infiltrating lymphocytes and cells that have the ultrastructural morphologic characteristics of dendritic cells. The origin of graft dendritic cells was sought in nine sex-mismatched recipients using XY fluorescence in situ hybridization. Whereas donor dendritic cells predominated initially, the majority of dendritic cells in late allograft biopsy samples were of recipient origin. Our data highlight the prognostic value of dendritic cell density in allograft biopsy samples, suggest a new role for these cells in shaping graft inflammation, and provide a rationale for targeting dendritic cell recruitment to promote long-term allograft survival.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Molecular Mechanisms Regulating Human Dendritic Cell Development, Survival and Function

    NARCIS (Netherlands)

    L. van de Laar (Lianne)

    2011-01-01

    textabstractDendritic cells (DC) are professional antigen presenting cells (APC) with a dual function in the immune system. On the one hand, these specialized leukocytes are equipped to alert the immune system to invading pathogens or other danger signals. On the other, DC can promote tolerogenic re

  16. Time-course regulation of survival pathways by epicatechin on HepG2 cells.

    Science.gov (United States)

    Granado-Serrano, Ana Belén; Angeles Martín, María; Goya, Luis; Bravo, Laura; Ramos, Sonia

    2009-02-01

    Polyphenols, such as epicatechin, have been reported to exhibit a wide range of biological activities. The objective of the present study was to investigate the time-dependent regulation by epicatechin of survival/proliferation pathways in HepG2 cells. Treatment of HepG2 cells with 10 micromol/L epicatechin did not result in any cell damage up to 18 h, as evaluated by the lactate dehydrogenase assay. Moreover, the enhanced cell death evoked by an oxidative stress induced with tert-butyl hydroperoxide was prevented in the cells pretreated 4 or 18 h with epicatechin. Epicatechin-induced survival was a rapid event that was accompanied by early and sustained activation of major survival signaling proteins, such as AKT/phosphatidylinositol 3-kinase and extracellular-regulated kinase (activated from 5 min to 18 h), as well as protein kinase C (PKC)-alpha (30 min to 18 h), in concert with unaltered c-jun N-amino terminal kinase levels and early inactivation of key death-related signals like PKC-delta (5 min to 18 h). Additionally, reactive oxygen species generation was transiently reduced when cells were treated with 10 micromol/L epicatechin (15-240 min). These data suggest that epicatechin induces cellular survival through a tight regulation of survival/proliferation pathways that requires the integration of different signals and persists over time, the ultimate effect on HepG2 cells being regulated by the balance among these signals.

  17. Curcumin targets FOLFOX-surviving colon cancer cells via inhibition of EGFRs and IGF-1R.

    Science.gov (United States)

    Patel, Bhaumik B; Gupta, Deepshika; Elliott, Althea A; Sengupta, Vivek; Yu, Yingjie; Majumdar, Adhip P N

    2010-02-01

    Curcumin (diferuloylmethane), which has no discernible toxicity, inhibits initiation, promotion and progression of carcinogenesis. 5-Fluorouracil (5-FU) or 5-FU plus oxaliplatin (FOLFOX) remains the backbone of colorectal cancer chemotherapeutics, but produces an incomplete response resulting in survival of cells (chemo-surviving cells) that may lead to cancer recurrence. The present investigation was, therefore, undertaken to examine whether addition of curcumin to FOLFOX is a superior therapeutic strategy for chemo-surviving cells. Forty-eight-hour treatment of colon cancer HCT-116 and HT-29 cells with FOLFOX resulted in 60-70% survival, accompanied by a marked activation of insulin like growth factor-1 receptor (IGF-1R) and minor to moderate increase in epidermal growth factor receptor (EGFR), v-erb-b2 erythroblastic leukemia viral oncogene homolog 2 (HER-2) as well as v-akt murine thymoma viral oncogene homolog 1 (AKT), cyclooxygenase-2 (COX-2) and cyclin-D1. However, inclusion of curcumin to continued FOLFOX treatment for another 48 h greatly reduced the survival of these cells, accompanied by a concomitant reduction in activation of EGFR, HER-2, IGF-1R and AKT, as well as expression of COX-2 and cyclin-D1. More importantly, EGFR tyrosine kinase inhibitor gefitinib or attenuation of IGF-1R expression by the corresponding si-RNA caused a 30-60% growth inhibition of chemo-surviving HCT-116 cells. However, curcumin alone was found to be more effective than both gefitinib and IGF-1R si-RNA mediated growth inhibition of chemo-surviving HCT-116 cells and addition of FOLFOX to curcumin did not increase the growth inhibitory effect of curcumin. Our data suggest that inclusion of curcumin in conventional chemotherapeutic regimens could be an effective strategy to prevent the emergence of chemoresistant colon cancer cells.

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

    Science.gov (United States)

    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.

  19. Hypoxic preconditioning improves survival of cardiac progenitor cells: role of stromal cell derived factor-1α-CXCR4 axis.

    Directory of Open Access Journals (Sweden)

    Fengdi Yan

    Full Text Available BACKGROUND: Cardiac progenitor cells (CPCs have been shown to be suitable in stem cell therapy for resurrecting damaged myocardium, but poor retention of transplanted cells in the ischemic myocardium causes ineffective cell therapy. Hypoxic preconditioning of cells can increase the expression of CXCR4 and pro-survival genes to promote better cell survival; however, it is unknown whether hypoxia preconditioning will influence the survival and retention of CPCs via the SDF-1α/CXCR4 axis. METHODS AND RESULTS: CPCs were isolated from adult mouse hearts and purified by magnetic activated cell sorting using c-kit magnetic beads. These cells were cultured at various times in either normoxic or hypoxic conditions, and cell survival was analyzed using flow cytometry and the expression of hypoxia-inducible factor-1α (HIF-1α, CXCR4, phosphorylated Akt and Bcl-2 were measured by Western blot. Results showed that the expression of pro-survival genes significantly increased after hypoxia treatment, especially in cells cultured in hypoxic conditions for six hours. Upon completion of hypoxia preconditioning from c-kit+ CPCs for six hours, the anti-apoptosis, migration and cardiac repair potential were evaluated. Results showed a significant enhancement in anti-apoptosis and migration in vitro, and better survival and cardiac function after being transplanted into acute myocardial infarction (MI mice in vivo. The beneficial effects induced by hypoxia preconditioning of c-kit+ CPCs could largely be blocked by the addition of CXCR4 selective antagonist AMD3100. CONCLUSIONS: Hypoxic preconditioning may improve the survival and retention of c-kit+ CPCs in the ischemic heart tissue through activating the SDF-1α/CXCR4 axis and the downstream anti-apoptosis pathway. Strategies targeting this aspect may enhance the effectiveness of cell-based cardiac regenerative therapy.

  20. Kuwanon V inhibits proliferation, promotes cell survival and increases neurogenesis of neural stem cells.

    Directory of Open Access Journals (Sweden)

    Sun-Young Kong

    Full Text Available Neural stem cells (NSCs have the ability to proliferate and differentiate into neurons and glia. Regulation of NSC fate by small molecules is important for the generation of a certain type of cell. The identification of small molecules that can induce new neurons from NSCs could facilitate regenerative medicine and drug development for neurodegenerative diseases. In this study, we screened natural compounds to identify molecules that are effective on NSC cell fate determination. We found that Kuwanon V (KWV, which was isolated from the mulberry tree (Morus bombycis root, increased neurogenesis in rat NSCs. In addition, during NSC differentiation, KWV increased cell survival and inhibited cell proliferation as shown by 5-bromo-2-deoxyuridine pulse experiments, Ki67 immunostaining and neurosphere forming assays. Interestingly, KWV enhanced neuronal differentiation and decreased NSC proliferation even in the presence of mitogens such as epidermal growth factor and fibroblast growth factor 2. KWV treatment of NSCs reduced the phosphorylation of extracellular signal-regulated kinase 1/2, increased mRNA expression levels of the cyclin-dependent kinase inhibitor p21, down-regulated Notch/Hairy expression levels and up-regulated microRNA miR-9, miR-29a and miR-181a. Taken together, our data suggest that KWV modulates NSC fate to induce neurogenesis, and it may be considered as a new drug candidate that can regenerate or protect neurons in neurodegenerative diseases.

  1. Influence of pro-angiogenic cytokines on proliferative activity and survival of endothelial cells

    Directory of Open Access Journals (Sweden)

    Solyanik G. I.

    2010-04-01

    Full Text Available Aim. Tumor angiogenesis in contrast to physiological one is characterized by high level of malignant cell production of proangiogenic cytokines, which have different influence on functional activity of endothelial cells. The goal of the study – to carry out a comparative analysis of the influence of a vascular endothelial growth factor (VEGF and an epidermal growth factor (EGF on proliferative activity and survival of endothelial cells upon their confluent and exponential growth. Methods. The proliferative activity of endothelial cells was determined by MTT-test and their viability was detected by the trypane blue exclusion test. Results. It was shown that EGF (irrespectively of the level of serum factors in concentrations higher than 10 ng/ml activated the proliferative activity of confluent endotheliocytes in a concentration-dependent manner by 18–36 % (ð < 0.05 as compared to the control, while this cytokine didn’t affect the endothelial cells in the exponential growth phase. VEGF in wide concentration range didn’t display the mitogenic effect on endotheliocytes in both confluent and exponential growth phases. Furthermore, VEGF in concentrations higher than 100 ng/ml inhibited proliferative activity of confluent endothelial cells by 12 % (ð < 0.05. In case of deficiency of nutrients, EGF and VEGF promoted the survival of endothelial cells, considerably decreasing their death. Conclusions. EGF, in contrast to VEGF, stimulates proliferation and survival of the endothelial cells, whereas VEGF has significant influence only on the survival of the cells

  2. A RUNX2-Mediated Epigenetic Regulation of the Survival of p53 Defective Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Min Hwa Shin

    2016-02-01

    Full Text Available The inactivation of p53 creates a major challenge for inducing apoptosis in cancer cells. An attractive strategy is to identify and subsequently target the survival signals in p53 defective cancer cells. Here we uncover a RUNX2-mediated survival signal in p53 defective cancer cells. The inhibition of this signal induces apoptosis in cancer cells but not non-transformed cells. Using the CRISPR technology, we demonstrate that p53 loss enhances the apoptosis caused by RUNX2 knockdown. Mechanistically, RUNX2 provides the survival signal partially through inducing MYC transcription. Cancer cells have high levels of activating histone marks on the MYC locus and concomitant high MYC expression. RUNX2 knockdown decreases the levels of these histone modifications and the recruitment of the Menin/MLL1 (mixed lineage leukemia 1 complex to the MYC locus. Two inhibitors of the Menin/MLL1 complex induce apoptosis in p53 defective cancer cells. Together, we identify a RUNX2-mediated epigenetic mechanism of the survival of p53 defective cancer cells and provide a proof-of-principle that the inhibition of this epigenetic axis is a promising strategy to kill p53 defective cancer cells.

  3. A RUNX2-Mediated Epigenetic Regulation of the Survival of p53 Defective Cancer Cells.

    Science.gov (United States)

    Shin, Min Hwa; He, Yunlong; Marrogi, Eryney; Piperdi, Sajida; Ren, Ling; Khanna, Chand; Gorlick, Richard; Liu, Chengyu; Huang, Jing

    2016-02-01

    The inactivation of p53 creates a major challenge for inducing apoptosis in cancer cells. An attractive strategy is to identify and subsequently target the survival signals in p53 defective cancer cells. Here we uncover a RUNX2-mediated survival signal in p53 defective cancer cells. The inhibition of this signal induces apoptosis in cancer cells but not non-transformed cells. Using the CRISPR technology, we demonstrate that p53 loss enhances the apoptosis caused by RUNX2 knockdown. Mechanistically, RUNX2 provides the survival signal partially through inducing MYC transcription. Cancer cells have high levels of activating histone marks on the MYC locus and concomitant high MYC expression. RUNX2 knockdown decreases the levels of these histone modifications and the recruitment of the Menin/MLL1 (mixed lineage leukemia 1) complex to the MYC locus. Two inhibitors of the Menin/MLL1 complex induce apoptosis in p53 defective cancer cells. Together, we identify a RUNX2-mediated epigenetic mechanism of the survival of p53 defective cancer cells and provide a proof-of-principle that the inhibition of this epigenetic axis is a promising strategy to kill p53 defective cancer cells.

  4. Hyaluronan Tumor Cell Interactions in Prostate Cancer Growth and Survival

    Science.gov (United States)

    2008-12-01

    RHAMM remaining following CD44 knockdown. Secondly, RHAMM will be knocked down using RNAi and the level of CD44 remaining will be measured using Western...hyaluronidase pretreatment or by using RNAi for the hyaluronan synthase enzymes expressed by these cells. The prediction, again, is that limiting HA...vertebrates and is not found in lower organisms or in insects (Fig. 9.2). Given its roles in such important cellular processes as motility and cell division in

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

    Science.gov (United States)

    Sutherland, John C

    2014-09-07

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Nanosecond pulsed electric field induced cytoskeleton, nuclear membrane and telomere damage adversely impact cell survival.

    Science.gov (United States)

    Stacey, M; Fox, P; Buescher, S; Kolb, J

    2011-10-01

    We investigated the effects of nanosecond pulsed electric fields (nsPEF) on three human cell lines and demonstrated cell shrinkage, breakdown of the cytoskeleton, nuclear membrane and chromosomal telomere damage. There was a differential response between cell types coinciding with cell survival. Jurkat cells showed cytoskeleton, nuclear membrane and telomere damage that severely impacted cell survival compared to two adherent cell lines. Interestingly, disruption of the actin cytoskeleton in adherent cells prior to nsPEF exposure significantly reduced cell survival. We conclude that nsPEF applications are able to induce damage to the cytoskeleton and nuclear membrane. Telomere sequences, regions that tether and stabilize DNA to the nuclear membrane, are severely compromised as measured by a pan-telomere probe. Internal pore formation following nsPEF applications has been described as a factor in induced cell death. Here we suggest that nsPEF induced physical changes to the cell in addition to pore formation need to be considered as an alternative method of cell death. We suggest nsPEF electrochemical induced depolymerization of actin filaments may account for cytoskeleton and nuclear membrane anomalies leading to sensitization.

  8. Sonic Hedgehog Produced by Bone Marrow-Derived Mesenchymal Stromal Cells Supports Cell Survival in Myelodysplastic Syndrome

    Directory of Open Access Journals (Sweden)

    Jixue Zou

    2015-01-01

    Full Text Available The role of marrow microenvironment in the pathogenesis of myelodysplastic syndrome (MDS remains controversial. Therefore, we studied the influence of bone marrow-derived mesenchymal stromal cells (BMSCs from patients with different risk types of MDS on the survival of the MDS cell lines SKM-1 and MUTZ-1. We first demonstrated that the expression of Sonic hedgehog (Shh, smoothened (Smo, and glioma-associated oncogene homolog 1 (Gli1 was increased in MDS patients n=23; the increase in expression was positively correlated with the presence of high-risk factors. The Shh signaling inhibitor, cyclopamine, inhibited high-risk MDS BMSC-induced survival of SKM-1 and MUTZ-1 cells, suggesting a role for Shh signaling in MDS cell survival. Furthermore, cyclopamine-mediated inhibition of Shh signaling in SKM-1 and MUTZ-1 cells resulted in decreased DNMT1 expression and cell survival; however, exogenous Shh peptide had the opposite effect, suggesting that Shh signaling could regulate the expression of DNMT1, thereby modulating cell survival in MDS. In addition, the apoptosis of SKM-1 and MUTZ-1 cell increased significantly when cultured with cyclopamine and a demethylation agent, 5-Aza-2′-deoxycytidine. These findings suggest that Shh signaling from BMSCs is important in the pathogenesis of MDS and could play a role in disease progression by modulating methylation.

  9. Programmed cell death in trypanosomatids: is it an altruistic mechanism for survival of the fittest?

    Science.gov (United States)

    Debrabant, Alain; Nakhasi, Hira

    2003-06-25

    The protozoan parasites Leishmania, Trypanosoma cruzi and Trypanosoma brucei show multiple features consistent with a form of programmed cell death (PCD). Despite some similarities with apoptosis of mammalian cells, PCD in trypanosomatid protozoans appears to be significantly different. In these unicellular organisms, PCD could represent an altruistic mechanism for the selection of cells, from the parasite population, that are fit to be transmitted to the next host. Alternatively, PCD could help in controlling the population of parasites in the host, thereby increasing host survival and favoring parasite transmission, as proposed by Seed and Wenk. Therefore, PCD in trypanosomatid parasites may represent a pathway involved both in survival and propagation of the species.

  10. Determination of cell survival after irradiation via clonogenic assay versus multiple MTT Assay - A comparative study

    Directory of Open Access Journals (Sweden)

    Buch Karl

    2012-01-01

    Full Text Available Abstract For studying proliferation and determination of survival of cancer cells after irradiation, the multiple MTT assay, based on the reduction of a yellow water soluble tetrazolium salt to a purple water insoluble formazan dye by living cells was modified from a single-point towards a proliferation assay. This assay can be performed with a large number of samples in short time using multi-well-plates, assays can be performed semi-automatically with a microplate reader. Survival, the calculated parameter in this assay, is determined mathematically. Exponential growth in both control and irradiated groups was proven as the underlying basis of the applicability of the multiple MTT assay. The equivalence to a clonogenic survival assay with its disadvantages such as time consumption was proven in two setups including plating of cells before and after irradiation. Three cell lines (A 549, LN 229 and F 98 were included in the experiment to study its principal and general applicability.

  11. Sox2 promotes survival of satellite glial cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    DEFF Research Database (Denmark)

    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...

  13. Astrocytes Upregulate Survival Genes in Tumor Cells and Induce Protection from Chemotherapy

    Directory of Open Access Journals (Sweden)

    Sun-Jin Kim

    2011-03-01

    Full Text Available In the United States, more than 40% of cancer patients develop brain metastasis. The median survival for untreated patients is 1 to 2 months, which may be extended to 6 months with conventional radiotherapy and chemotherapy. The growth and survival of metastasis depend on the interaction of tumor cells with host factors in the organ microenvironment. Brain metastases are surrounded and infiltrated by activated astrocytes and are highly resistant to chemotherapy. We report here that coculture of human breast cancer cells or lung cancer cells with murine astrocytes (but not murine fibroblasts led to the up-regulation of survival genes, including GSTA5, BCL2L1, and TWIST1, in the tumor cells. The degree of up-regulation directly correlated with increased resistance to all tested chemotherapeutic agents. We further show that the up-regulation of the survival genes and consequent resistance are dependent on the direct contact between the astrocytes and tumor cells through gap junctions and are therefore transient. Knocking down these genes with specific small interfering RNA rendered the tumor cells sensitive to chemotherapeutic agents. These data clearly demonstrate that host cells in the microenvironment influence the biologic behavior of tumor cells and reinforce the contention that the organ microenvironment must be taken into consideration during the design of therapy.

  14. Unbiased and automated identification of a circulating tumour cell definition that associates with overall survival

    NARCIS (Netherlands)

    Ligthart, S.T.; Coumans, F.A.W.; Attard, G.; Mukick Cassidy, A.; Bono, de J.S.; Terstappen, L.W.M.M.

    2011-01-01

    Circulating tumour cells (CTC) in patients with metastatic carcinomas are associated with poor survival and can be used to guide therapy. Classification of CTC however remains subjective, as they are morphologically heterogeneous. We acquired digital images, using the CellSearch™ system, from blood

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Ubiquitin at the crossroad of cell death and survival

    Institute of Scientific and Technical Information of China (English)

    Yu-Shan Chen; Xiao-Bo Qiu

    2013-01-01

    Ubiquitination is crucial for cellular processes, such as protein degradation, apoptosis, autophagy, and cell cycle progression. Dysregulation of the ubiquitination network accounts for the development of numerous diseases, including cancer. Thus, targeting ubiquitination is a promising strategy in cancer therapy. Both apoptosis and autophagy are involved in tumorigenesis and response to cancer therapy. Although both are categorized as types of celldeath, autophagy is general y considered to have protective functions, including protecting cells from apoptosis under certain cellular stress conditions. This review highlights recent advances in understanding the regulation of apoptosis and autophagy by ubiquitination.

  17. Repetitive transarterial chemoembolization (TACE) of liver metastases from renal cell carcinoma: Local control and survival results

    Energy Technology Data Exchange (ETDEWEB)

    Nabil, Mohamed [Johann Wolfgang Goethe University, Institute of Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Klinikum der Johann Wolfgang Goethe-Universitaet, Institut fuer Diagnostische und Interventionelle Radiologie, Frankfurt am Main (Germany); Gruber, Tatjana; Zangos, Stephan; Vogl, Thomas J. [Johann Wolfgang Goethe University, Institute of Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Yakoub, Danny [Imperial College London, St Mary' s Hospital, Department of Biosurgery and Surgical Technology, London (United Kingdom); Ackermann, Hanns [Johann Wolfgang Goethe University, Department of Biostatistics and Medical Information, Frankfurt am Main (Germany)

    2008-07-15

    The purpose was to evaluate the effectiveness of transarterial chemoembolization (TACE) in local tumor control and survival in patients with hepatic metastases from renal cell carcinoma (RCC). Prospective evaluation of TACE treatment outcome in 22 patients recruited from 1999 and 2005 was performed. The chemotherapeutic agent used was mitomycin only in 45% of the patients and mitomycin together with gemcitabine in the other 55%. The embolizing materials used in all of the patients were iodized oil (lipiodol) and degradable starch microspheres. Local response was evaluated by MRI and judged according to Response Evaluation Criteria in Solid Tumors (RECIST). Mean and median survival and survival probability after diagnosis and treatment were both calculated by Kaplan-Meier method. Partial response was achieved in 13.7%, stable disease in 59% and progressive disease in 27.3% of patients. Survival time from the diagnosis of metastases ranged from 18 to 307 months and from 2.2 to 35 months from the start of TACE treatment. The median and mean survival times from the date of diagnosis were 68.6 and 102.9 months, respectively. The median and mean survival times from the start of TACE were 8.2 and 11.7 months, respectively. Survival probability from the start of treatment was 31% after 1 year and 6% after 2 years. TACE can result in a favorable local tumor response in patients with hepatic metastases from RCC, but survival results are still limited. (orig.)

  18. Dietary Pectin Increases Intestinal Crypt Stem Cell Survival following Radiation Injury.

    Directory of Open Access Journals (Sweden)

    Sripathi M Sureban

    Full Text Available Gastrointestinal (GI mucosal damage is a devastating adverse effect of radiation therapy. We have recently reported that expression of Dclk1, a Tuft cell and tumor stem cell (TSC marker, 24h after high dose total-body gamma-IR (TBI can be used as a surrogate marker for crypt survival. Dietary pectin has been demonstrated to possess chemopreventive properties, whereas its radioprotective property has not been studied. The aim of this study was to determine the effects of dietary pectin on ionizing radiation (IR-induced intestinal stem cell (ISC deletion, crypt and overall survival following lethal TBI. C57BL/6 mice received a 6% pectin diet and 0.5% pectin drinking water (pre-IR mice received pectin one week before TBI until death; post-IR mice received pectin after TBI until death. Animals were exposed to TBI (14 Gy and euthanized at 24 and 84h post-IR to assess ISC deletion and crypt survival respectively. Animals were also subjected to overall survival studies following TBI. In pre-IR treatment group, we observed a three-fold increase in ISC/crypt survival, a two-fold increase in Dclk1+ stem cells, increased overall survival (median 10d vs. 7d, and increased expression of Dclk1, Msi1, Lgr5, Bmi1, and Notch1 (in small intestine post-TBI in pectin treated mice compared to controls. We also observed increased survival of mice treated with pectin (post-IR compared to controls. Dietary pectin is a radioprotective agent; prevents IR-induced deletion of potential reserve ISCs; facilitates crypt regeneration; and ultimately promotes overall survival. Given the anti-cancer activity of pectin, our data support a potential role for dietary pectin as an agent that can be administered to patients receiving radiation therapy to protect against radiation-induces mucositis.

  19. Dietary Pectin Increases Intestinal Crypt Stem Cell Survival following Radiation Injury.

    Science.gov (United States)

    Sureban, Sripathi M; May, Randal; Qu, Dongfeng; Chandrakesan, Parthasarathy; Weygant, Nathaniel; Ali, Naushad; Lightfoot, Stan A; Ding, Kai; Umar, Shahid; Schlosser, Michael J; Houchen, Courtney W

    2015-01-01

    Gastrointestinal (GI) mucosal damage is a devastating adverse effect of radiation therapy. We have recently reported that expression of Dclk1, a Tuft cell and tumor stem cell (TSC) marker, 24h after high dose total-body gamma-IR (TBI) can be used as a surrogate marker for crypt survival. Dietary pectin has been demonstrated to possess chemopreventive properties, whereas its radioprotective property has not been studied. The aim of this study was to determine the effects of dietary pectin on ionizing radiation (IR)-induced intestinal stem cell (ISC) deletion, crypt and overall survival following lethal TBI. C57BL/6 mice received a 6% pectin diet and 0.5% pectin drinking water (pre-IR mice received pectin one week before TBI until death; post-IR mice received pectin after TBI until death). Animals were exposed to TBI (14 Gy) and euthanized at 24 and 84h post-IR to assess ISC deletion and crypt survival respectively. Animals were also subjected to overall survival studies following TBI. In pre-IR treatment group, we observed a three-fold increase in ISC/crypt survival, a two-fold increase in Dclk1+ stem cells, increased overall survival (median 10d vs. 7d), and increased expression of Dclk1, Msi1, Lgr5, Bmi1, and Notch1 (in small intestine) post-TBI in pectin treated mice compared to controls. We also observed increased survival of mice treated with pectin (post-IR) compared to controls. Dietary pectin is a radioprotective agent; prevents IR-induced deletion of potential reserve ISCs; facilitates crypt regeneration; and ultimately promotes overall survival. Given the anti-cancer activity of pectin, our data support a potential role for dietary pectin as an agent that can be administered to patients receiving radiation therapy to protect against radiation-induces mucositis.

  20. Impaired survival of regulatory T cells in pulmonary sarcoidosis

    NARCIS (Netherlands)

    C.E. Broos (Caroline); M. van Nimwegen (Menno); A. Kleinjan (Alex); B. ten Berge (Bregje); F. Muskens (Femke); J.C.C.M. in 't Veen (Johannes); J.T. Annema (Jouke); B.N.M. Lambrecht (Bart); H.C. Hoogsteden (Henk); R.W. Hendriks (Rudi); M. Kool (Mirjam); B. van den Blink (Bernt)

    2015-01-01

    textabstractBackground: Impaired regulatory T cell (Treg) function is thought to contribute to ongoing inflammatory responses in sarcoidosis, but underlying mechanisms remain unclear. Moreover, it is not known if increased apoptotic susceptibility of Tregs may contribute to an impaired immunosuppres

  1. EEN regulates the proliferation and survival of multiple myeloma cells by potentiating IGF-1 secretion

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Er-Wen [Guangzhou Institute of Forensic Science, Guangzhou (China); Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Xue, Sheng-Jiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Li, Xiao-Yan [Department of Pharmacy, The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China); Xu, Suo-Wen [Department of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou (China); Cheng, Jian-Ding; Zheng, Jin-Xiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong [Guangzhou Institute of Forensic Science, Guangzhou (China); Li, Jie, E-mail: mdlijie@sina.com [Department of Anaesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou (China); Liu, Chao, E-mail: liuchaogaj@21cn.com [Guangzhou Institute of Forensic Science, Guangzhou (China)

    2014-05-02

    Highlights: • Levels of EEN expression paralleled with the rate of cell proliferation. • EEN was involved in the proliferation and survival of multiple myeloma (MM) cells. • EEN regulated the activity of IGF-1-Akt/mTOR pathway. • EEN regulated proliferation and survival of MM cells by enhancing IGF-1 secretion. - Abstract: The molecular mechanisms of multiple myeloma are not well defined. EEN is an endocytosis-regulating molecule. Here we report that EEN regulates the proliferation and survival of multiple myeloma cells, by regulating IGF-1 secretion. In the present study, we observed that EEN expression paralleled with cell proliferation, EEN accelerated cell proliferation, facilitated cell cycle transition from G1 to S phase by regulating cyclin-dependent kinases (CDKs) pathway, and delayed cell apoptosis via Bcl2/Bax-mitochondrial pathway. Mechanistically, we found that EEN was indispensable for insulin-like growth factor-1 (IGF-1) secretion and the activation of protein kinase B-mammalian target of rapamycin (Akt-mTOR) pathway. Exogenous IGF-1 overcame the phenotype of EEN depletion, while IGF-1 neutralization overcame that of EEN over-expression. Collectively, these data suggest that EEN may play a pivotal role in excessive cell proliferation and insufficient cell apoptosis of bone marrow plasma cells in multiple myeloma. Therefore, EEN may represent a potential diagnostic marker or therapeutic target for multiple myeloma.

  2. Polysialic acid sustains cancer cell survival and migratory capacity in a hypoxic environment

    Science.gov (United States)

    Elkashef, Sara M.; Allison, Simon J.; Sadiq, Maria; Basheer, Haneen A.; Ribeiro Morais, Goreti; Loadman, Paul M.; Pors, Klaus; Falconer, Robert A.

    2016-01-01

    Polysialic acid (polySia) is a unique carbohydrate polymer expressed on the surface of NCAM (neuronal cell adhesion molecule) in a number of cancers where it modulates cell-cell and cell-matrix adhesion, migration, invasion and metastasis and is strongly associated with poor clinical prognosis. We have carried out the first investigation into the effect of polySia expression on the behaviour of cancer cells in hypoxia, a key source of chemoresistance in tumours. The role of polysialylation and associated tumour cell migration and cell adhesion were studied in hypoxia, along with effects on cell survival and the potential role of HIF-1. Our findings provide the first evidence that polySia expression sustains migratory capacity and is associated with tumour cell survival in hypoxia. Initial mechanistic studies indicate a potential role for HIF-1 in sustaining polySia-mediated migratory capacity, but not cell survival. These data add to the growing body of evidence pointing to a crucial role for the polysialyltransferases (polySTs) in neuroendocrine tumour progression and provide the first evidence to suggest that polySia is associated with an aggressive phenotype in tumour hypoxia. These results have significant potential implications for polyST inhibition as an anti-metastatic therapeutic strategy and for targeting hypoxic cancer cells. PMID:27611649

  3. Enhanced auditory neuron survival following cell-based BDNF treatment in the deaf guinea pig.

    Directory of Open Access Journals (Sweden)

    Lisa N Pettingill

    Full Text Available Exogenous neurotrophin delivery to the deaf cochlea can prevent deafness-induced auditory neuron degeneration, however, we have previously reported that these survival effects are rapidly lost if the treatment stops. In addition, there are concerns that current experimental techniques are not safe enough to be used clinically. Therefore, for such treatments to be clinically transferable, methods of neurotrophin treatment that are safe, biocompatible and can support long-term auditory neuron survival are necessary. Cell transplantation and gene transfer, combined with encapsulation technologies, have the potential to address these issues. This study investigated the survival-promoting effects of encapsulated BDNF over-expressing Schwann cells on auditory neurons in the deaf guinea pig. In comparison to control (empty capsules, there was significantly greater auditory neuron survival following the cell-based BDNF treatment. Concurrent use of a cochlear implant is expected to result in even greater auditory neuron survival, and provide a clinically relevant method to support auditory neuron survival that may lead to improved speech perception and language outcomes for cochlear implant patients.

  4. Aromatase expression increases the survival and malignancy of estrogen receptor positive breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Keya De Mukhopadhyay

    Full Text Available In postmenopausal women, local estrogen produced by adipose stromal cells in the breast is believed to support estrogen receptor alpha (ERα positive breast cancer cell survival and growth. This raises the question of how the ERα positive metastatic breast cancer cells survive after they enter blood and lymph circulation, where estrogen level is very low in postmenopausal women. In this study, we show that the aromatase expression increased when ERα positive breast cancer cells were cultured in suspension. Furthermore, treatment with the aromatase substrate, testosterone, inhibited suspension culture-induced apoptosis whereas an aromatase inhibitor attenuated the effect of testosterone suggesting that suspended circulating ERα positive breast cancer cells may up-regulate intracrine estrogen activity for survival. Consistent with this notion, a moderate level of ectopic aromatase expression rendered a non-tumorigenic ERα positive breast cancer cell line not only tumorigenic but also metastatic in female nude mice without exogenous estrogen supplementation. The increased malignant phenotype was confirmed to be due to aromatase expression as the growth of orthotopic tumors regressed with systemic administration of an aromatase inhibitor. Thus, our study provides experimental evidence that aromatase plays an important role in the survival of metastatic ERα breast cancer cells by suppressing anoikis.

  5. Modelling circulating tumour cells for personalised survival prediction in metastatic breast cancer.

    Directory of Open Access Journals (Sweden)

    Gianluca Ascolani

    2015-05-01

    Full Text Available Ductal carcinoma is one of the most common cancers among women, and the main cause of death is the formation of metastases. The development of metastases is caused by cancer cells that migrate from the primary tumour site (the mammary duct through the blood vessels and extravasating they initiate metastasis. Here, we propose a multi-compartment model which mimics the dynamics of tumoural cells in the mammary duct, in the circulatory system and in the bone. Through a branching process model, we describe the relation between the survival times and the four markers mainly involved in metastatic breast cancer (EPCAM, CD47, CD44 and MET. In particular, the model takes into account the gene expression profile of circulating tumour cells to predict personalised survival probability. We also include the administration of drugs as bisphosphonates, which reduce the formation of circulating tumour cells and their survival in the blood vessels, in order to analyse the dynamic changes induced by the therapy. We analyse the effects of circulating tumour cells on the progression of the disease providing a quantitative measure of the cell driver mutations needed for invading the bone tissue. Our model allows to design intervention scenarios that alter the patient-specific survival probability by modifying the populations of circulating tumour cells and it could be extended to other cancer metastasis dynamics.

  6. Piezoelectric Drop-on-Demand Inkjet Printing of Rat Fibroblast Cells: Survivability Study and Pattern Printing

    CERN Document Server

    Li, Er Qiang; Thoroddsen, Sigurdur Tryggvi

    2013-01-01

    A novel piezoelectric, drop-on-demand (DOD) inkjet system has been developed and used to print L929 rat fibroblast cells. We investigate the survivability of the cells subjected to the large stresses during the printing process. These stresses are varied by changing the diameter of the orifice (36 to 119 microns) through which the cells are dispensed, as well as changing the electrical pulse used to drive the piezoelectric element. It is shown that for the smallest 36 microns diameter orifice, cell survival rates fall from 95% to approximately 76% when the ejection velocity is increased from 2 to 16 m/s. This decrease in survival rates is less significant when the larger orifice diameters of 81 microns and 119 microns are used. Analysis shows that there is a clear inverse relationship between cell survival rates and the mean shear rates during drop formation. By using the same printing set-up, fibroblast cells are printed onto alginate and collagen into patterns. Printed cells are cultured over a period of da...

  7. Dendritic cell immunotherapy versus bevacizumab plus irinotecan in recurrent malignant glioma patients: a survival gain analysis

    Science.gov (United States)

    Artene, Stefan-Alexandru; Turcu-Stiolica, Adina; Hartley, Richard; Ciurea, Marius Eugen; Daianu, Oana; Brindusa, Corina; Alexandru, Oana; Tataranu, Ligia Gabriela; Purcaru, Stefana Oana; Dricu, Anica

    2016-01-01

    Background The bevacizumab and irinotecan protocol is considered a standard treatment regimen for recurrent malignant glioma. Recent advances in immunotherapy have hinted that vaccination with dendritic cells could become an alternative salvage therapy for the treatment of recurrent malignant glioma. Methods A search was performed on PubMed, Cochrane Library, Web of Science, ScienceDirect, and Embase in order to identify studies with patients receiving bevacizumab plus irinotecan or dendritic cell therapy for recurrent malignant gliomas. The data obtained from these studies were used to perform a systematic review and survival gain analysis. Results Fourteen clinical studies with patients receiving either bevacizumab plus irinotecan or dendritic cell vaccination were identified. Seven studies followed patients that received bevacizumab plus irinotecan (302 patients) and seven studies included patients that received dendritic cell immunotherapy (80 patients). For the patients who received bevacizumab plus irinotecan, the mean reported median overall survival was 7.5 (95% confidence interval [CI] 4.84–10.16) months. For the patients who received dendritic cell immunotherapy, the mean reported median overall survival was 17.9 (95% CI 11.34–24.46) months. For irinotecan + bevacizumab group, the mean survival gain was −0.02±2.00, while that for the dendritic cell immunotherapy group was −0.01±4.54. Conclusion For patients with recurrent malignant gliomas, dendritic cell immunotherapy treatment does not have a significantly different effect when compared with bevacizumab and irinotecan in terms of survival gain (P=0.535) and does not improve weighted survival gain (P=0.620). PMID:27877052

  8. Endobronchial mucosa invasion predicts survival in patients with small cell lung cancer.

    Directory of Open Access Journals (Sweden)

    Pai-Chien Chou

    Full Text Available BACKGROUND: Current staging system for small cell lung cancer (SCLC categorizes patients into limited- or extensive-stage disease groups according to anatomical localizations. Even so, a wide-range of survival times has been observed among patients in the same staging system. This study aimed to identify whether endobronchial mucosa invasion is an independent predictor for poor survival in patients with SCLC, and to compare the survival time between patients with and without endobronchial mucosa invasion. METHODS: We studied 432 consecutive patients with SCLC based on histological examination of biopsy specimens or on fine-needle aspiration cytology, and received computed tomography and bone scan for staging. All the enrolled patients were assessed for endobronchial mucosa invasion by bronchoscopic and histological examination. Survival days were compared between patients with or without endobronchial mucosa invasion and the predictors of decreased survival days were investigated. RESULTS: 84% (364/432 of SCLC patients had endobronchial mucosal invasion by cancer cells at initial diagnosis. Endobronchial mucosal involvement (Hazard ratio [HR], 2.01; 95% Confidence Interval [CI], 1.30-3.10, age (HR, 1.04; 95% CI, 1.03-1.06, and extensive stage (HR, 1.39; 95% CI, 1.06-1.84 were independent contributing factors for shorter survival time, while received chemotherapy (HR, 0.32; 95% CI, 0.25-0.42 was an independent contributing factor better outcome. The survival days of SCLC patients with endobronchial involvement were markedly decreased compared with patients without (median 145 vs. 290, p<0.0001. Among SCLC patients of either limited (median 180 vs. 460, p<0.0001 or extensive (median 125 vs. 207, p<0.0001 stages, the median survival duration for patients with endobronchial mucosal invasion was shorter than those with intact endobronchial mucosa, respectively. CONCLUSION: Endobronchial mucosal involvement is an independent prognostic factor for SCLC

  9. Fasting protects mice from lethal DNA damage by promoting small intestinal epithelial stem cell survival.

    Science.gov (United States)

    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.

  10. Fasting protects mice from lethal DNA damage by promoting small intestinal epithelial stem cell survival

    Science.gov (United States)

    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

    2015-01-01

    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. PMID:26644583

  11. Placental growth factor is a survival factor for tumor endothelial cells and macrophages.

    Science.gov (United States)

    Adini, Avner; Kornaga, Tad; Firoozbakht, Farshid; Benjamin, Laura E

    2002-05-15

    The vascular endothelial growth factor (VEGF)-related factor, placental growth factor (PlGF),has been shown recently to play an important role in pathological VEGF-driven angiogenesis. In this study, we examine the effects of mPlGF/PlGF-2 overexpression in tumors grown from glioma cells containing a tetracycline-regulated mPlGF cDNA. Overexpression of mPlGF leads to increased tumor growth and vascular survival. When tetracycline is used to abruptly withdraw mPlGF overexpression, we see increased apoptosis in both vascular cells and macrophages. In addition, PlGF-2 induces survival gene expression and inhibits apoptosis in vitro. Thus, we propose that PlGF-2 contributes to tumor angiogenesis by providing increased survival function to endothelial cells and macrophages.

  12. Transplanted microvascular endothelial cells promote oligodendrocyte precursor cell survival in ischemic demyelinating lesions.

    Science.gov (United States)

    Iijima, Keiya; Kurachi, Masashi; Shibasaki, Koji; Naruse, Masae; Puentes, Sandra; Imai, Hideaki; Yoshimoto, Yuhei; Mikuni, Masahiko; Ishizaki, Yasuki

    2015-11-01

    We previously showed that transplantation of brain microvascular endothelial cells (MVECs) greatly stimulated remyelination in the white matter infarct of the internal capsule (IC) induced by endothelin-1 injection and improved the behavioral outcome. In the present study, we examined the effect of MVEC transplantation on the infarct volume using intermittent magnetic resonance image and on the behavior of oligodendrocyte lineage cells histochemically. Our results in vivo show that MVEC transplantation reduced the infarct volume in IC and apoptotic death of oligodendrocyte precursor cells (OPCs). These results indicate that MVECs have a survival effect on OPCs, and this effect might contribute to the recovery of the white matter infarct. The conditioned-medium from cultured MVECs reduced apoptosis of cultured OPCs, while the conditioned medium from cultured fibroblasts did not show such effect. These results suggest a possibility that transplanted MVECs increased the number of OPCs through the release of humoral factors that prevent their apoptotic death. Identification of such humoral factors may lead to the new therapeutic strategy against ischemic demyelinating diseases.

  13. Expression of β-globin by cancer cells promotes cell survival during blood-borne dissemination

    Science.gov (United States)

    Zheng, Yu; Miyamoto, David T.; Wittner, Ben S.; Sullivan, James P.; Aceto, Nicola; Jordan, Nicole Vincent; Yu, Min; Karabacak, Nezihi Murat; Comaills, Valentine; Morris, Robert; Desai, Rushil; Desai, Niyati; Emmons, Erin; Milner, John D.; Lee, Richard J.; Wu, Chin-Lee; Sequist, Lecia V.; Haas, Wilhelm; Ting, David T.; Toner, Mehmet; Ramaswamy, Sridhar; Maheswaran, Shyamala; Haber, Daniel A.

    2017-01-01

    Metastasis-competent circulating tumour cells (CTCs) experience oxidative stress in the bloodstream, but their survival mechanisms are not well defined. Here, comparing single-cell RNA-Seq profiles of CTCs from breast, prostate and lung cancers, we observe consistent induction of β-globin (HBB), but not its partner α-globin (HBA). The tumour-specific origin of HBB is confirmed by sequence polymorphisms within human xenograft-derived CTCs in mouse models. Increased intracellular reactive oxygen species (ROS) in cultured breast CTCs triggers HBB induction, mediated through the transcriptional regulator KLF4. Depletion of HBB in CTC-derived cultures has minimal effects on primary tumour growth, but it greatly increases apoptosis following ROS exposure, and dramatically reduces CTC-derived lung metastases. These effects are reversed by the anti-oxidant N-Acetyl Cysteine. Conversely, overexpression of HBB is sufficient to suppress intracellular ROS within CTCs. Altogether, these observations suggest that β-globin is selectively deregulated in cancer cells, mediating a cytoprotective effect during blood-borne metastasis. PMID:28181495

  14. IL-7 modulates B cells survival and activation by inducing BAFF and CD70 expression in T cells.

    Science.gov (United States)

    Sammicheli, Stefano; Ruffin, Nicolas; Lantto, Rebecka; Vivar, Nancy; Chiodi, Francesca; Rethi, Bence

    2012-06-01

    Interleukin-7 (IL-7) promotes the maintenance and activation of peripheral T cells, whereas it does not act directly on mature B cells due to the lack of IL-7Rα expression on these. We report here that, in spite of the insensitivity of B cells to IL-7, high concentration of IL-7 can lead to increased B cell survival and antibody production in the presence of T cells, without the use of any further B cell stimulatory signal. IL-7 promoted B cell activation through inducing CD70 expression on resting T cells, particularly on CD4+ memory cells. The interaction of CD70 molecules with the B cell costimulatory receptor CD27 led to B cell proliferation, the accumulation of CD38 + CD20- plasmablasts and antibody production. In addition, IL-7 treatment induced BAFF secretion from resting peripheral T cells thereby promoting B cell survival. IL-7 levels can increase in lymphopenic conditions, in autoimmune diseases or in patients receiving T cell regenerative IL-7 therapy. Based on our findings high IL-7 levels can lead to increased B cell activation by inducing the B cell regulatory proteins CD70 and BAFF in resting T cells. Such activity might be beneficial in short term immune-stimulatory IL-7 therapies; permanently increased IL-7 levels, on the other hand, can contribute to impaired B cell tolerance.

  15. A naringenin–tamoxifen combination impairs cell proliferation and survival of MCF-7 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    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

  16. Correlation of Particle Traversals with Clonogenic Survival Using Cell-Fluorescent Ion Track Hybrid Detector

    Science.gov (United States)

    Dokic, Ivana; Niklas, Martin; Zimmermann, Ferdinand; Mairani, Andrea; Seidel, Philipp; Krunic, Damir; Jäkel, Oliver; Debus, Jürgen; Greilich, Steffen; Abdollahi, Amir

    2015-01-01

    Development of novel approaches linking the physical characteristics of particles with biological responses are of high relevance for the field of particle therapy. In radiobiology, the clonogenic survival of cells is considered the gold standard assay for the assessment of cellular sensitivity to ionizing radiation. Toward further development of next generation biodosimeters in particle therapy, cell-fluorescent ion track hybrid detector (Cell-FIT-HD) was recently engineered by our group and successfully employed to study physical particle track information in correlation with irradiation-induced DNA damage in cell nuclei. In this work, we investigated the feasibility of Cell-FIT-HD as a tool to study the effects of clinical beams on cellular clonogenic survival. Tumor cells were grown on the fluorescent nuclear track detector as cell culture, mimicking the standard procedures for clonogenic assay. Cell-FIT-HD was used to detect the spatial distribution of particle tracks within colony-initiating cells. The physical data were associated with radiation-induced foci as surrogates for DNA double-strand breaks, the hallmark of radiation-induced cell lethality. Long-term cell fate was monitored to determine the ability of cells to form colonies. We report the first successful detection of particle traversal within colony-initiating cells at subcellular resolution using Cell-FIT-HD. PMID:26697410

  17. Correlation of Particle Traversals with Clonogenic Survival Using Cell-Fluorescent Ion Track Hybrid Detector

    Directory of Open Access Journals (Sweden)

    Ivana eDokic

    2015-12-01

    Full Text Available Development of novel approaches linking the physical characteristics of particles with biological responses are of high relevance for the field of particle therapy. In radiobiology, the clonogenic survival of cells is considered the gold standard assay for assessment of cellular sensitivity to ionizing radiation. Towards further development of next generation biodosimeters in particle therapy, cell-fluorescent ion track hybrid detector (Cell-FIT-HD was recently engineered by our group and successfully employed to study physical particle track information in correlation with irradiation- induced DNA damage in cell nuclei. In this work, we investigated the feasibility of Cell-FIT-HD as a tool to study the effects of clinical beams on cellular clonogenic survival. Tumor cells were grown on the FNTD as cell culture, mimicking the standard procedures for clonogenic assay. Cell-FIT-HD was used to detect the spatial distribution of particle tracks within colony-initiating cells. The physical data were associated to radiation induced foci as surrogates for DNA double strand breakages (DSB, the hallmark of radiation ‐induced cell lethality. Long‐term cell fate was monitored to determine the ability of cells to form colonies. We report the first successful detection of particle traversal within colony-initiating cells at subcellular resolution using Cell-FIT-HD.

  18. Exosomes Derived from Squamous Head and Neck Cancer Promote Cell Survival after Ionizing Radiation.

    Science.gov (United States)

    Mutschelknaus, Lisa; Peters, Carsten; Winkler, Klaudia; Yentrapalli, Ramesh; Heider, Theresa; Atkinson, Michael John; Moertl, Simone

    2016-01-01

    Exosomes are nanometer-sized extracellular vesicles that are believed to function as intercellular communicators. Here, we report that exosomes are able to modify the radiation response of the head and neck cancer cell lines BHY and FaDu. Exosomes were isolated from the conditioned medium of irradiated as well as non-irradiated head and neck cancer cells by serial centrifugation. Quantification using NanoSight technology indicated an increased exosome release from irradiated compared to non-irradiated cells 24 hours after treatment. To test whether the released exosomes influence the radiation response of other cells the exosomes were transferred to non-irradiated and irradiated recipient cells. We found an enhanced uptake of exosomes isolated from both irradiated and non-irradiated cells by irradiated recipient cells compared to non-irradiated recipient cells. Functional analyses by exosome transfer indicated that all exosomes (from non-irradiated and irradiated donor cells) increase the proliferation of non-irradiated recipient cells and the survival of irradiated recipient cells. The survival-promoting effects are more pronounced when exosomes isolated from irradiated compared to non-irradiated donor cells are transferred. A possible mechanism for the increased survival after irradiation could be the increase in DNA double-strand break repair monitored at 6, 8 and 10 h after the transfer of exosomes isolated from irradiated cells. This is abrogated by the destabilization of the exosomes. Our results demonstrate that radiation influences both the abundance and action of exosomes on recipient cells. Exosomes transmit prosurvival effects by promoting the proliferation and radioresistance of head and neck cancer cells. Taken together, this study indicates a functional role of exosomes in the response of tumor cells to radiation exposure within a therapeutic dose range and encourages that exosomes are useful objects of study for a better understanding of tumor

  19. AKT/GSK3β signaling pathway is critically involved in human pluripotent stem cell survival

    Science.gov (United States)

    Romorini, Leonardo; Garate, Ximena; Neiman, Gabriel; Luzzani, Carlos; Furmento, Verónica Alejandra; Guberman, Alejandra Sonia; Sevlever, Gustavo Emilio; Scassa, María Elida; Miriuka, Santiago Gabriel

    2016-01-01

    Human embryonic and induced pluripotent stem cells are self-renewing pluripotent stem cells (PSC) that can differentiate into a wide range of specialized cells. Basic fibroblast growth factor is essential for PSC survival, stemness and self-renewal. PI3K/AKT pathway regulates cell viability and apoptosis in many cell types. Although it has been demonstrated that PI3K/AKT activation by bFGF is relevant for PSC stemness maintenance its role on PSC survival remains elusive. In this study we explored the molecular mechanisms involved in the regulation of PSC survival by AKT. We found that inhibition of AKT with three non-structurally related inhibitors (GSK690693, AKT inhibitor VIII and AKT inhibitor IV) decreased cell viability and induced apoptosis. We observed a rapid increase in phosphatidylserine translocation and in the extent of DNA fragmentation after inhibitors addition. Moreover, abrogation of AKT activity led to Caspase-9, Caspase-3, and PARP cleavage. Importantly, we demonstrated by pharmacological inhibition and siRNA knockdown that GSK3β signaling is responsible, at least in part, of the apoptosis triggered by AKT inhibition. Moreover, GSK3β inhibition decreases basal apoptosis rate and promotes PSC proliferation. In conclusion, we demonstrated that AKT activation prevents apoptosis, partly through inhibition of GSK3β, and thus results relevant for PSC survival. PMID:27762303

  20. Kaiso depletion attenuates the growth and survival of triple negative breast cancer cells.

    Science.gov (United States)

    Bassey-Archibong, Blessing I; Rayner, Lyndsay G A; Hercules, Shawn M; Aarts, Craig W; Dvorkin-Gheva, Anna; Bramson, Jonathan L; Hassell, John A; Daniel, Juliet M

    2017-03-23

    Triple negative breast cancers (TNBC) are highly aggressive and lack specific targeted therapies. Recent studies have reported high expression of the transcription factor Kaiso in triple negative tumors, and this correlates with their increased aggressiveness. However, little is known about the clinical relevance of Kaiso in the growth and survival of TNBCs. Herein, we report that Kaiso depletion attenuates TNBC cell proliferation, and delays tumor onset in mice xenografted with the aggressive MDA-231 breast tumor cells. We further demonstrate that Kaiso depletion attenuates the survival of TNBC cells and increases their propensity for apoptotic-mediated cell death. Notably, Kaiso depletion downregulates BRCA1 expression in TNBC cells expressing mutant-p53 and we found that high Kaiso and BRCA1 expression correlates with a poor overall survival in breast cancer patients. Collectively, our findings reveal a role for Kaiso in the proliferation and survival of TNBC cells, and suggest a relevant role for Kaiso in the prognosis and treatment of TNBCs.

  1. Novel Function of TNF Cytokines in Regulating Bone Marrow B Cell Survival

    Institute of Scientific and Technical Information of China (English)

    MinZhang; King-HungKo; QueenieLaiKwanLam; CherryKamChunLo; DanielJiaLinXu; LijunShen; BojianZheng; GopeshSrivastava; LiweiLu

    2004-01-01

    Two newly identified tumor necrosis factor (TNF) family cytokines, B cell activation factor from the TNF family (BAFF) and a proliferation-inducing ligand (APRIL), have recently been shown to enhance the maturation and survival of peripheral B cells. However, whether BAFF and APRIL are expressed in the bone marrow (BM) microenvironment and if these two cytokines modulate early B cell development remain unclear.In the present study, we have detected the abundant expression of BAFF and APRIL transcripts in BM non-lymphoid cells. Low levels of BAFF and APRIL mRNA are also found in developing B cells. Furthermore,we have determined the expression patterns of BAFF receptors during B lymphopoiesis. In cultures, both recombinant BAFF and APRIL significantly promote the survival of precursor B cells whereas only BAFF can suppress apoptosis of immature B cells. These findings suggest that BAFF and APRIL, in addition to their well established role in regulating peripheral B cell growth, can modulate the survival of developing B cells in the BM. Cellular & Molecular Immunology. 2004;1(6):447-453.

  2. Role of adipose-derived stromal cells in pedicle skin flap survival in experimental animal models

    Institute of Scientific and Technical Information of China (English)

    Pericles; Foroglou; Vasileios; Karathanasis; Efterpi; Demiri; George; Koliakos; Marios; Papadakis

    2016-01-01

    The use of skin flaps in reconstructive surgery is the first-line surgical treatment for the reconstruction of skin defects and is essentially considered the starting point of plastic surgery. Despite their excellent usability, their application includes general surgical risks or possible complications, the primary and most common is necrosis of the flap. To improve flap survival, researchers have used different methods, including the use of adiposederived stem cells, with significant positive results. In our research we will report the use of adipose-derived stem cells in pedicle skin flap survival based on current literature on various experimental models in animals.

  3. Role of adipose-derived stromal cells in pedicle skin flap survival in experimental animal models.

    Science.gov (United States)

    Foroglou, Pericles; Karathanasis, Vasileios; Demiri, Efterpi; Koliakos, George; Papadakis, Marios

    2016-03-26

    The use of skin flaps in reconstructive surgery is the first-line surgical treatment for the reconstruction of skin defects and is essentially considered the starting point of plastic surgery. Despite their excellent usability, their application includes general surgical risks or possible complications, the primary and most common is necrosis of the flap. To improve flap survival, researchers have used different methods, including the use of adipose-derived stem cells, with significant positive results. In our research we will report the use of adipose-derived stem cells in pedicle skin flap survival based on current literature on various experimental models in animals.

  4. How to Improve the Survival of Transplanted Mesenchymal Stem Cell in Ischemic Heart?

    Directory of Open Access Journals (Sweden)

    Liangpeng Li

    2016-01-01

    Full Text Available Mesenchymal stem cell (MSC is an intensely studied stem cell type applied for cardiac repair. For decades, the preclinical researches on animal model and clinical trials have suggested that MSC transplantation exerts therapeutic effect on ischemic heart disease. However, there remain major limitations to be overcome, one of which is the very low survival rate after transplantation in heart tissue. Various strategies have been tried to improve the MSC survival, and many of them showed promising results. In this review, we analyzed the studies in recent years to summarize the methods, effects, and mechanisms of the new strategies to address this question.

  5. Mitochondrial calcium uniporter activity is dispensable for MDA-MB-231 breast carcinoma cell survival.

    Science.gov (United States)

    Hall, Duane D; Wu, Yuejin; Domann, Frederick E; Spitz, Douglas R; Anderson, Mark E

    2014-01-01

    Calcium uptake through the mitochondrial Ca2+ uniporter (MCU) is thought to be essential in regulating cellular signaling events, energy status, and survival. Functional dissection of the uniporter is now possible through the recent identification of the genes encoding for MCU protein complex subunits. Cancer cells exhibit many aspects of mitochondrial dysfunction associated with altered mitochondrial Ca2+ levels including resistance to apoptosis, increased reactive oxygen species production and decreased oxidative metabolism. We used a publically available database to determine that breast cancer patient outcomes negatively correlated with increased MCU Ca2+ conducting pore subunit expression and decreased MICU1 regulatory subunit expression. We hypothesized breast cancer cells may therefore be sensitive to MCU channel manipulation. We used the widely studied MDA-MB-231 breast cancer cell line to investigate whether disruption or increased activation of mitochondrial Ca2+ uptake with specific siRNAs and adenoviral overexpression constructs would sensitize these cells to therapy-related stress. MDA-MB-231 cells were found to contain functional MCU channels that readily respond to cellular stimulation and elicit robust AMPK phosphorylation responses to nutrient withdrawal. Surprisingly, knockdown of MCU or MICU1 did not affect reactive oxygen species production or cause significant effects on clonogenic cell survival of MDA-MB-231 cells exposed to irradiation, chemotherapeutic agents, or nutrient deprivation. Overexpression of wild type or a dominant negative mutant MCU did not affect basal cloning efficiency or ceramide-induced cell killing. In contrast, non-cancerous breast epithelial HMEC cells showed reduced survival after MCU or MICU1 knockdown. These results support the conclusion that MDA-MB-231 breast cancer cells do not rely on MCU or MICU1 activity for survival in contrast to previous findings in cells derived from cervical, colon, and prostate cancers and

  6. Mitochondrial calcium uniporter activity is dispensable for MDA-MB-231 breast carcinoma cell survival.

    Directory of Open Access Journals (Sweden)

    Duane D Hall

    Full Text Available Calcium uptake through the mitochondrial Ca2+ uniporter (MCU is thought to be essential in regulating cellular signaling events, energy status, and survival. Functional dissection of the uniporter is now possible through the recent identification of the genes encoding for MCU protein complex subunits. Cancer cells exhibit many aspects of mitochondrial dysfunction associated with altered mitochondrial Ca2+ levels including resistance to apoptosis, increased reactive oxygen species production and decreased oxidative metabolism. We used a publically available database to determine that breast cancer patient outcomes negatively correlated with increased MCU Ca2+ conducting pore subunit expression and decreased MICU1 regulatory subunit expression. We hypothesized breast cancer cells may therefore be sensitive to MCU channel manipulation. We used the widely studied MDA-MB-231 breast cancer cell line to investigate whether disruption or increased activation of mitochondrial Ca2+ uptake with specific siRNAs and adenoviral overexpression constructs would sensitize these cells to therapy-related stress. MDA-MB-231 cells were found to contain functional MCU channels that readily respond to cellular stimulation and elicit robust AMPK phosphorylation responses to nutrient withdrawal. Surprisingly, knockdown of MCU or MICU1 did not affect reactive oxygen species production or cause significant effects on clonogenic cell survival of MDA-MB-231 cells exposed to irradiation, chemotherapeutic agents, or nutrient deprivation. Overexpression of wild type or a dominant negative mutant MCU did not affect basal cloning efficiency or ceramide-induced cell killing. In contrast, non-cancerous breast epithelial HMEC cells showed reduced survival after MCU or MICU1 knockdown. These results support the conclusion that MDA-MB-231 breast cancer cells do not rely on MCU or MICU1 activity for survival in contrast to previous findings in cells derived from cervical, colon, and

  7. δ-Catenin promotes prostate cancer cell growth and progression by altering cell cycle and survival gene profiles

    Directory of Open Access Journals (Sweden)

    Chen Yan-Hua

    2009-03-01

    Full Text Available Abstract Background δ-Catenin is a unique member of β-catenin/armadillo domain superfamily proteins and its primary expression is restricted to the brain. However, δ-catenin is upregulated in human prostatic adenocarcinomas, although the effects of δ-catenin overexpression in prostate cancer are unclear. We hypothesized that δ-catenin plays a direct role in prostate cancer progression by altering gene profiles of cell cycle regulation and cell survival. Results We employed gene transfection and small interfering RNA to demonstrate that increased δ-catenin expression promoted, whereas its knockdown suppressed prostate cancer cell viability. δ-Catenin promoted prostate cancer cell colony formation in soft agar as well as tumor xenograft growth in nude mice. Deletion of either the amino-terminal or carboxyl-terminal sequences outside the armadillo domains abolished the tumor promoting effects of δ-catenin. Quantitative RT2 Profiler™ PCR Arrays demonstrated gene alterations involved in cell cycle and survival regulation. δ-Catenin overexpression upregulated cyclin D1 and cdc34, increased phosphorylated histone-H3, and promoted the entry of mitosis. In addition, δ-catenin overexpression resulted in increased expression of cell survival genes Bcl-2 and survivin while reducing the cell cycle inhibitor p21Cip1. Conclusion Taken together, our studies suggest that at least one consequence of an increased expression of δ-catenin in human prostate cancer is the alteration of cell cycle and survival gene profiles, thereby promoting tumor progression.

  8. Human Hematopoietic Stem Cells Can Survive In Vitro for Several Months

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    Taro Ishigaki

    2009-01-01

    Full Text Available We previously reported that long-lasting in vitro hematopoiesis could be achieved using the cells differentiated from primate embryonic stem (ES cells. Thus, we speculated that hematopoietic stem cells differentiated from ES cells could sustain long-lasting in vitro hematopoiesis. To test this hypothesis, we investigated whether human hematopoietic stem cells could similarly sustain long-lasting in vitro hematopoiesis in the same culture system. Although the results varied between experiments, presumably due to differences in the quality of each hematopoietic stem cell sample, long-lasting in vitro hematopoiesis was observed to last up to nine months. Furthermore, an in vivo analysis in which cultured cells were transplanted into immunodeficient mice indicated that even after several months of culture, hematopoietic stem cells were still present in the cultured cells. To the best of our knowledge, this is the first report to show that human hematopoietic stem cells can survive in vitro for several months.

  9. Statin use is associated with improved survival in patients undergoing surgery for renal cell carcinoma

    DEFF Research Database (Denmark)

    Kaffenberger, Samuel D; Lin-Tsai, Opal; Stratton, Kelly L

    2015-01-01

    ) and disease-specific survival (DSS). Univariable survival analyses were performed using the Kaplan-Meier and the log-rank methods. Multivariable analysis was performed using a Cox proportional hazards model. The predictive discrimination of the models was assessed using the Harrell c-index. RESULTS......: 0.43-0.90; P = 0.011) and DSS (hazard ratio = 0.48; 95% CI: 0.28-0.83; P = 0.009). The multivariable model for DSS had excellent predictive discrimination with a c-index of 0.91. CONCLUSIONS: These data suggest that statin usage at time of surgery is independently associated with improved OS and DSS......PURPOSE: To determine whether statin use at time of surgery is associated with survival following nephrectomy or partial nephrectomy for renal cell carcinoma (RCC). Statins are thought to exhibit a protective effect on cancer incidence and possibly cancer survival in a number of malignancies...

  10. Hypoxia inducible factor 1α promotes survival of mesenchymal stem cells under hypoxia

    Science.gov (United States)

    Lv, Bingke; Li, Feng; Fang, Jie; Xu, Limin; Sun, Chengmei; Han, Jianbang; Hua, Tian; Zhang, Zhongfei; Feng, Zhiming; Jiang, Xiaodan

    2017-01-01

    Mesenchymal stem cells (MSCs) are ideal materials for cell therapy. Research has indicated that hypoxia benefits MSC survival, but little is known about the underlying mechanism. This study aims to uncover potential mechanisms involving hypoxia inducible factor 1α (HIF1A) to explain the promoted MSC survival under hypoxia. MSCs were obtained from Sprague-Dawley rats and cultured under normoxia or hypoxia condition. The overexpression vector or small interfering RNA of Hif1a gene was transfected to MSCs, after which cell viability, apoptosis and expression of HIF1A were analyzed by MTT assay, flow cytometry, qRT-PCR and Western blot. Factors in p53 pathway were detected to reveal the related mechanisms. Results showed that hypoxia elevated MSCs viability and up-regulated HIF1A (P cell CLL/lymphoma 2 (BCL2) expression had the opposite pattern (P cell therapy.

  11. Neurogenesis and Increase in Differentiated Neural Cell Survival via Phosphorylation of Akt1 after Fluoxetine Treatment of Stem Cells

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    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.

  12. TRPML: transporters of metals in lysosomes essential for cell survival?

    Science.gov (United States)

    Kiselyov, Kirill; Colletti, Grace A; Terwilliger, Austen; Ketchum, Kathleen; Lyons, Christopher W P; Quinn, James; Muallem, Shmuel

    2011-09-01

    Key aspects of lysosomal function are affected by the ionic content of the lysosomal lumen and, therefore, by the ion permeability in the lysosomal membrane. Such functions include regulation of lysosomal acidification, a critical process in delivery and activation of the lysosomal enzymes, release of metals from lysosomes into the cytoplasm and the Ca(2+)-dependent component of membrane fusion events in the endocytic pathway. While the basic mechanisms of lysosomal acidification have been largely defined, the lysosomal metal transport system is not well understood. TRPML1 is a lysosomal ion channel whose malfunction is implicated in the lysosomal storage disease Mucolipidosis Type IV. Recent evidence suggests that TRPML1 is involved in Fe(2+), Ca(2+) and Zn(2+) transport across the lysosomal membrane, ascribing novel physiological roles to this ion channel, and perhaps to its relatives TRPML2 and TRPML3 and illuminating poorly understood aspects of lysosomal function. Further, alterations in metal transport by the TRPMLs due to mutations or environmental factors may contribute to their role in the disease phenotype and cell death.

  13. Dorsomorphin promotes survival and germline competence of zebrafish spermatogonial stem cells in culture.

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    Ten-Tsao Wong

    Full Text Available Zebrafish spermatogonial cell cultures were established from Tg(piwil1:neo;Tg(piwil1:DsRed transgenic fish using a zebrafish ovarian feeder cell line (OFC3 that was engineered to express zebrafish Lif, Fgf2 and Gdnf. Primary cultures, initiated from testes, were treated with G418 to eliminate the somatic cells and select for the piwil1:neo expressing spermatogonia. Addition of dorsomorphin, a Bmp type I receptor inhibitor, prolonged spermatogonial stem cell (SSC survival in culture and enhanced germline transmission of the SSCs following transplantation into recipient larvae. In contrast, dorsomorphin inhibited the growth and survival of zebrafish female germline stem cells (FGSCs in culture. In the presence of dorsomorphin, the spermatogonia continued to express the germ-cell markers dazl, dnd, nanos3, vasa and piwil1 and the spermatogonial markers plzf and sox17 for at least six weeks in culture. Transplantation experiments revealed that 6 week-old spermatogonial cell cultures maintained in the presence of dorsomorphin were able to successfully colonize the gonad in 18% of recipient larvae and produce functional gametes in the resulting adult chimeric fish. Germline transmission was not successful when the spermatogonia were cultured 6 weeks in the absence of dorsomorphin before transplantation. The results indicate that Bmp signaling is detrimental to SSCs but required for the survival of zebrafish FGSCs in culture. Manipulation of Bmp signaling could provide a strategy to optimize culture conditions of germline stem cells from other species.

  14. β-Catenin signaling increases during melanoma progression and promotes tumor cell survival and chemoresistance.

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    Tobias Sinnberg

    Full Text Available Beta-catenin plays an important role in embryogenesis and carcinogenesis by controlling either cadherin-mediated cell adhesion or transcriptional activation of target gene expression. In many types of cancers nuclear translocation of beta-catenin has been observed. Our data indicate that during melanoma progression an increased dependency on the transcriptional function of beta-catenin takes place. Blockade of beta-catenin in metastatic melanoma cell lines efficiently induces apoptosis, inhibits proliferation, migration and invasion in monolayer and 3-dimensional skin reconstructs and decreases chemoresistance. In addition, subcutaneous melanoma growth in SCID mice was almost completely inhibited by an inducible beta-catenin knockdown. In contrast, the survival of benign melanocytes and primary melanoma cell lines was less affected by beta-catenin depletion. However, enhanced expression of beta-catenin in primary melanoma cell lines increased invasive capacity in vitro and tumor growth in the SCID mouse model. These data suggest that beta-catenin is an essential survival factor for metastatic melanoma cells, whereas it is dispensable for the survival of benign melanocytes and primary, non-invasive melanoma cells. Furthermore, beta-catenin increases tumorigenicity of primary melanoma cell lines. The differential requirements for beta-catenin signaling in aggressive melanoma versus benign melanocytic cells make beta-catenin a possible new target in melanoma therapy.

  15. Targeting TGF-β1 suppresses survival of and invasion by anaplastic thyroid carcinoma cells

    Science.gov (United States)

    Sun, Wenhai; Xu, Yanyan; Zhao, Cheng; Hao, Fengyun; Chen, Dong; Guan, Jinping; Zhang, Kejun

    2017-01-01

    Background and aims: Overexpression of transforming growth factor (TGF)-β1 has been implicated in promoting cell survival, migration and invasion in many cancers, including anaplastic thyroid cancer (ATC). In the present study, we studied the effect of suppressing TGF-β1 by RNA silencing on the survival, invasion and metastasis of ATC cells. Methods: Small interfering RNA (siRNA) constructs targeting TGF-β1 were validated and used to develop clonal derivatives of the ATC cell line, 8505C. The cells were used in several in vitro assays, including migration, invasion, survival rate, colony formation and apoptosis. A wound healing assay was used to determine the migration of cells in culture and a Boyden chamber transwell assay was used for invasion. Further, clones were used in an in vivo mouse model to study the kinetics of tumor growth and metastatic growth in lungs. Results: Targeting TGF-β1 expression in 8505C cells caused a 70% decrease in migration and a 78% decrease in invasion, as well as a 68% decrease in proliferation and a 19% increase in apoptosis in vitro. The growth of primary tumors in vivo was also inhibited when compared with parental 8505C cells; however, the number of mice bearing lung metastases was not significantly decreased. Conclusions: Targeting TGF-β1 may be effective in inhibiting primary tumor formation, but not metastasis, by ATC cells. TGF-β1 inhibition in combination with other tumor-targeted therapies may be more effective in inhibiting ATC.

  16. Club cells surviving influenza A virus infection induce temporary nonspecific antiviral immunity.

    Science.gov (United States)

    Hamilton, Jennifer R; Sachs, David; Lim, Jean K; Langlois, Ryan A; Palese, Peter; Heaton, Nicholas S

    2016-04-01

    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.

  17. Stochastic modeling and experimental analysis of phenotypic switching and survival of cancer cells under stress

    Science.gov (United States)

    Zamani Dahaj, Seyed Alireza; Kumar, Niraj; Sundaram, Bala; Celli, Jonathan; Kulkarni, Rahul

    The phenotypic heterogeneity of cancer cells is critical to their survival under stress. A significant contribution to heterogeneity of cancer calls derives from the epithelial-mesenchymal transition (EMT), a conserved cellular program that is crucial for embryonic development. Several studies have investigated the role of EMT in growth of early stage tumors into invasive malignancies. Also, EMT has been closely associated with the acquisition of chemoresistance properties in cancer cells. Motivated by these studies, we analyze multi-phenotype stochastic models of the evolution of cancers cell populations under stress. We derive analytical results for time-dependent probability distributions that provide insights into the competing rates underlying phenotypic switching (e.g. during EMT) and the corresponding survival of cancer cells. Experimentally, we evaluate these model-based predictions by imaging human pancreatic cancer cell lines grown with and without cytotoxic agents and measure growth kinetics, survival, morphological changes and (terminal evaluation of) biomarkers with associated epithelial and mesenchymal phenotypes. The results derived suggest approaches for distinguishing between adaptation and selection scenarios for survival in the presence of external stresses.

  18. A Hyaluronan-Based Injectable Hydrogel Improves the Survival and Integration of Stem Cell Progeny following Transplantation

    Directory of Open Access Journals (Sweden)

    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.

  19. The influence of printing parameters on cell survival rate and printability in microextrusion-based 3D cell printing technology.

    Science.gov (United States)

    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.

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

    DEFF Research Database (Denmark)

    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...... of iPLA₂-VIA after SI exposure. Inhibitors of iPLA₂-VIA were used to explore a potential protective role in cells exposed to SI. Primary RPE cell cultures were grown from iPLA₂-VIA knockout mice and wild-type mice. The cultures were exposed to SI to investigate a possible increased protection against......-VIA-specific inhibitors in ARPE-19 cell cultures. RPE cultures from iPLA₂-VIA knockout mice were less vulnerable to SI-induced cell death compared to RPE cultures from wild-type mice. CONCLUSIONS: SI -induced RPE cell death involves iPLA₂-VIA upregulation and activation, and amelioration of SI...

  1. Survival Analysis of 1,742 Patients with Stage IV Non-small Cell Lung Cancer

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    Hong PENG

    2011-04-01

    Full Text Available Background and objective At present non-small cell lung cancer (NSCLC is still the leading cause of death induced by cancer. The aim of this study is to investigate the prognostic factors of advanced NSCLC. Methods Total 1,742 cases of stage IV NSCLC data from Jan 4, 2000 to Dec 25, 2008 in Shanghai Chest Hospital were collected, confirmed by pathological examinations. Analysis was made to observe the impact of treatment on prognosis in gender, age, smoking history, pathology, classification, clinical TNM stage. Survival rate, survival difference were evaluated by Kaplan-Meire method and Logrank test respectively. The prognosis were analyzed by Cox multivariate regression. Results The median survival time of 1,742 patients was 10.0 months (9.5 months-10.5 months. One, two, three, four, and five-year survival rates were 44%, 22%, 13%, 9%, 6% respectively. The median survivals of single or multiple metastasis were 11 months vs 7 months (P < 0.001. Survival time were different in metastasic organs, with the median survival time as follows: lung for about 12 months (11.0 months-12.9 months, bone for 9 months (8.3 months-9.6 months, brain for 8 months (6.8 months-9.1 months, liver, adrenal gland, distannt lymph node metastasis for 5 months (3.8 months-6.1 months, and subcutaneous for 3 months (1.7 months-4.3 months. The median survival times of adenocarcinoma (n=1,086, 62% and squamous cell carcinoma cases (n=305, 17.5% were 12 months vs 8 months (P < 0.001. The median survival time of chemotherapy and best supportive care were 11 months vs 6 months (P < 0.001; the median survival times of with and without radiotherapy were 11 months vs 9 months (P=0.017. Conclusion Gender, age, gross type, pathological type, clinical T stage, N stage, numbers of metastatic organ, smoking history, treatment of advanced non-small cell lung cancer were independent prognostic factors.

  2. Encapsulated Whole Bone Marrow Cells Improve Survival in Wistar Rats after 90% Partial Hepatectomy

    Directory of Open Access Journals (Sweden)

    Carolina Uribe-Cruz

    2016-01-01

    Full Text Available Background and Aims. The use of bone marrow cells has been suggested as an alternative treatment for acute liver failure. In this study, we investigate the effect of encapsulated whole bone marrow cells in a liver failure model. Methods. Encapsulated cells or empty capsules were implanted in rats submitted to 90% partial hepatectomy. The survival rate was assessed. Another group was euthanized at 6, 12, 24, 48, and 72 hours after hepatectomy to study expression of cytokines and growth factors. Results. Whole bone marrow group showed a higher than 10 days survival rate compared to empty capsules group. Gene expression related to early phase of liver regeneration at 6 hours after hepatectomy was decreased in encapsulated cells group, whereas genes related to regeneration were increased at 12, 24, and 48 hours. Whole bone marrow group showed lower regeneration rate at 72 hours and higher expression and activity of caspase 3. In contrast, lysosomal-β-glucuronidase activity was elevated in empty capsules group. Conclusions. The results show that encapsulated whole bone marrow cells reduce the expression of genes involved in liver regeneration and increase those responsible for ending hepatocyte division. In addition, these cells favor apoptotic cell death and decrease necrosis, thus increasing survival.

  3. L-Arginine Modulates T Cell Metabolism and Enhances Survival and Anti-tumor Activity.

    Science.gov (United States)

    Geiger, Roger; Rieckmann, Jan C; Wolf, Tobias; Basso, Camilla; Feng, Yuehan; Fuhrer, Tobias; Kogadeeva, Maria; Picotti, Paola; Meissner, Felix; Mann, Matthias; Zamboni, Nicola; Sallusto, Federica; Lanzavecchia, Antonio

    2016-10-20

    Metabolic activity is intimately linked to T cell fate and function. Using high-resolution mass spectrometry, we generated dynamic metabolome and proteome profiles of human primary naive T cells following activation. We discovered critical changes in the arginine metabolism that led to a drop in intracellular L-arginine concentration. Elevating L-arginine levels induced global metabolic changes including a shift from glycolysis to oxidative phosphorylation in activated T cells and promoted the generation of central memory-like cells endowed with higher survival capacity and, in a mouse model, anti-tumor activity. Proteome-wide probing of structural alterations, validated by the analysis of knockout T cell clones, identified three transcriptional regulators (BAZ1B, PSIP1, and TSN) that sensed L-arginine levels and promoted T cell survival. Thus, intracellular L-arginine concentrations directly impact the metabolic fitness and survival capacity of T cells that are crucial for anti-tumor responses.

  4. Caspase inhibitors promote vestibular hair cell survival and function after aminoglycoside treatment in vivo

    Science.gov (United States)

    Matsui, Jonathan I.; Haque, Asim; Huss, David; Messana, Elizabeth P.; Alosi, Julie A.; Roberson, David W.; Cotanche, Douglas A.; Dickman, J. David; Warchol, Mark E.

    2003-01-01

    The sensory hair cells of the inner ear undergo apoptosis after acoustic trauma or aminoglycoside antibiotic treatment, causing permanent auditory and vestibular deficits in humans. Previous studies have demonstrated a role for caspase activation in hair cell death and ototoxic injury that can be reduced by concurrent treatment with caspase inhibitors in vitro. In this study, we examined the protective effects of caspase inhibition on hair cell death in vivo after systemic injections of aminoglycosides. In one series of experiments, chickens were implanted with osmotic pumps that administrated the pan-caspase inhibitor z-Val-Ala-Asp(Ome)-fluoromethylketone (zVAD) into inner ear fluids. One day after the surgery, the animals received a 5 d course of treatment with streptomycin, a vestibulotoxic aminoglycoside. Direct infusion of zVAD into the vestibule significantly increased hair cell survival after streptomycin treatment. A second series of experiments determined whether rescued hair cells could function as sensory receptors. Animals treated with streptomycin displayed vestibular system impairment as measured by a greatly reduced vestibulo-ocular response (VOR). In contrast, animals that received concurrent systemic administration of zVAD with streptomycin had both significantly greater hair cell survival and significantly increased VOR responses, as compared with animals treated with streptomycin alone. These findings suggest that inhibiting the activation of caspases promotes the survival of hair cells and protects against vestibular function deficits after aminoglycoside treatment.

  5. Nifuroxazide inhibits survival of multiple myeloma cells by directly inhibiting STAT3.

    Science.gov (United States)

    Nelson, Erik A; Walker, Sarah R; Kepich, Alicia; Gashin, Laurie B; Hideshima, Teru; Ikeda, Hiroshi; Chauhan, Dharminder; Anderson, Kenneth C; Frank, David A

    2008-12-15

    Constitutive activation of the transcription factor STAT3 contributes to the pathogenesis of many cancers, including multiple myeloma (MM). Since STAT3 is dispensable in most normal tissue, targeted inhibition of STAT3 is an attractive therapy for patients with these cancers. To identify STAT3 inhibitors, we developed a transcriptionally based assay and screened a library of compounds known to be safe in humans. We found the drug nifuroxazide to be an effective inhibitor of STAT3 function. Nifuroxazide inhibits the constitutive phosphorylation of STAT3 in MM cells by reducing Jak kinase autophosphorylation, and leads to down-regulation of the STAT3 target gene Mcl-1. Nifuroxazide causes a decrease in viability of primary myeloma cells and myeloma cell lines containing STAT3 activation, but not normal peripheral blood mononuclear cells. Although bone marrow stromal cells provide survival signals to myeloma cells, nifuroxazide can overcome this survival advantage. Reflecting the interaction of STAT3 with other cellular pathways, nifuroxazide shows enhanced cytotoxicity when combined with either the histone deacetylase inhibitor depsipeptide or the MEK inhibitor UO126. Therefore, using a mechanistic-based screen, we identified the clinically relevant drug nifuroxazide as a potent inhibitor of STAT signaling that shows cytotoxicity against myeloma cells that depend on STAT3 for survival.

  6. Musashi1 regulates breast tumor cell proliferation and is a prognostic indicator of poor survival

    Directory of Open Access Journals (Sweden)

    Wang Xiao-Yang

    2010-08-01

    Full Text Available Abstract Background Musashi1 (Msi1 is a conserved RNA-binding protein that regulates the Notch and Wnt pathways, and serves as a stem cell marker in the breast and other tissues. It is unknown how Msi1 relates to other breast cancer markers, whether it denotes tumor initiating cells (TICs, and how it affects gene expression and tumor cell survival in breast cancer cells. Results Msi1 expression was analyzed in 20 breast cancer cell lines and in 140 primary breast tumors by western blotting and immunohistochemistry, respectively. Lentivirus RNA interference was used to reduce Msi1 expression in breast cancer cell lines MCF-7 and T47D grown as spheroid cultures and to assess stem cell gene expression and the growth of these cell lines as xenografts. In normal human breast tissue, Msi1 was expressed in 10.6% of myoepithelum and 1.2% of ductal epithelium in the terminal ductal lobular unit (TDLU, whereas, less than 0.05% of ductal epithelium and myoepithelium in large ducts outside the TDLU expressed Msi1. Msi1 was expressed in 55% of the breast cancer cell lines and correlated with ErbB2 expression in 50% of the cell lines. Msi1 was expressed in 68% of primary tumors and in 100% of lymph node metastases, and correlated with 5 year survival. Msi1 was enriched in CD133+ MCF-7 and T47D cells and in spheroid cultures of these cells, and Msi1 'knockdown' (KD with a lentivirus-expressed shRNA decreased the number and size of spheroid colonies. Msi1 KD reduced Notch1, c-Myc, ErbB2 and pERK1/2 expression, and increased p21CIP1 expression, which is consistent with known Msi1 target mRNAs. Msi1 KD also reduced the expression of the somatic and embryonic stem cell markers, CD133, Bmi1, Sox2, Nanog and Oct4. Xenografts of MCF-7 and T47D Msi1 KD cells resulted in a marked reduction of tumor growth, reduced Msi1 and Notch1 expression and increased p21CIP1 expression. Conclusion Msi1 is a negative prognostic indicator of breast cancer patient survival, and is

  7. LONG-TERM SURVIVAL OF SMALL-CELL LUNG-CANCER PATIENTS AFTER CHEMOTHERAPY

    NARCIS (Netherlands)

    VANDERGAAST, A; POSTMUS, PE; BURGHOUTS, J; VANBOLHUIS, C; STAM, J; SPLINTER, TAW

    1993-01-01

    Eighty-one patients with small cell lung cancer (SCLC) with a survival Of more than 2 years start of chemotherapy were studied. Twenty-six of the 28 patients who died of relapsed SCLC had in relapsed before two years and of the 55 who had not then only two (4%) relapsed subsequently. It is stressed

  8. Effects of cell-bound microcystins on survival and feeding of Daphnia spp

    DEFF Research Database (Denmark)

    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...

  9. Global Attractivity of Positive Periodic Solutions for a Survival Model of Red Blood Cells

    Institute of Scientific and Technical Information of China (English)

    Xin-min Wu; Jing-wen Li

    2007-01-01

    In this paper, we deal with a model for the survival of red blood cells with periodic coefficients x′(t)=- μ(t)x(t)+P(t)e-γ(t)x(t-(τ))>0. (*)A new sufficient condition for global attractivity of positive periodic solutions of Eq.(*) is obtained. Our criterion improves corresponding result obtained by Li and Wang in 2005.

  10. Campylobacter jejuni survives within epithelial cells by avoiding delivery to lysosomes.

    Directory of Open Access Journals (Sweden)

    Robert O Watson

    2008-01-01

    Full Text Available Campylobacter jejuni is one of the major causes of infectious diarrhea world-wide, although relatively little is know about its mechanisms of pathogenicity. This bacterium can gain entry into intestinal epithelial cells, which is thought to be important for its ability to persistently infect and cause disease. We found that C. jejuni is able to survive within intestinal epithelial cells. However, recovery of intracellular bacteria required pre-culturing under oxygen-limiting conditions, suggesting that C. jejuni undergoes significant physiological changes within the intracellular environment. We also found that in epithelial cells the C. jejuni-containing vacuole deviates from the canonical endocytic pathway immediately after a unique caveolae-dependent entry pathway, thus avoiding delivery into lysosomes. In contrast, in macrophages, C. jejuni is delivered to lysosomes and consequently is rapidly killed. Taken together, these studies indicate that C. jejuni has evolved specific adaptations to survive within host cells.

  11. RGDS-fuctionalized alginates improve the survival rate of encapsulated embryonic stem cells during cryopreservation.

    Science.gov (United States)

    Sambu, S; Xu, X; Schiffer, H A; Cui, Z F; Ye, H

    2011-01-01

    Cryopreservation of stem cells, especially embryonic stem cells, is problematic because of low post-thaw cell survival rates and spontaneous differentiation following recovery. In this investigation, mouse embryonic stem cells (mESCs) were encapsulated in arginine-glycine-aspartic acid-serine (RGDS)-coupled calcium alginates (1.2 percent, w/v), allowed to attach to the substratum and then cryopreserved in 10 percent (v/v) dimethyl sulfoxide (DMSO) solution at a slow cooling rate of 1 C per min. RGDS coupling to alginate was confirmed by Transmission Fourier Transform Infra-Red spectroscopy (T-FTIR) and quantified by using ninhydrin-Ultraviolet/Visible light (ninhydrin-UV/VIS) assay. Flow cytometry data showed that mESCs cryopreserved in RGDS-alginate beads had a higher expression of stem cell markers compared with cells cryopreserved in suspension or cells cryopreserved in unmodified alginates. Cell viability after thawing was assessed using trypan blue exclusion assay and monitored using Alamar blue assay for 6 hours. It was shown that post-thaw cell survival rate was significantly higher for cells encapsulated in RGDS-modified alginate (93 ± 2 percent, mean and standard error) than those in suspension (52 ± 2 percent) or in unmodified alginates (62 ± 3 percent). These results showed that cells encapsulated and attached to a substratum have better survival rate and stem cell marker expression 24 hours after cryopreservation than those in suspension. Encapsulation in RGDS-alginate was optimized for peptide concentration, cryoprotective agent loading time and cooling rate. The best result was obtained when using 12.5 mg peptide per g alginate, 30 minutes loading time and 1 C per min cooling rate.

  12. A simple prognostic model for overall survival in metastatic renal cell carcinoma

    Science.gov (United States)

    Assi, Hazem I.; Patenaude, Francois; Toumishey, Ethan; Ross, Laura; Abdelsalam, Mahmoud; Reiman, Tony

    2016-01-01

    Introduction: The primary purpose of this study was to develop a simpler prognostic model to predict overall survival for patients treated for metastatic renal cell carcinoma (mRCC) by examining variables shown in the literature to be associated with survival. Methods: We conducted a retrospective analysis of patients treated for mRCC at two Canadian centres. All patients who started first-line treatment were included in the analysis. A multivariate Cox proportional hazards regression model was constructed using a stepwise procedure. Patients were assigned to risk groups depending on how many of the three risk factors from the final multivariate model they had. Results: There were three risk factors in the final multivariate model: hemoglobin, prior nephrectomy, and time from diagnosis to treatment. Patients in the high-risk group (two or three risk factors) had a median survival of 5.9 months, while those in the intermediate-risk group (one risk factor) had a median survival of 16.2 months, and those in the low-risk group (no risk factors) had a median survival of 50.6 months. Conclusions: In multivariate analysis, shorter survival times were associated with hemoglobin below the lower limit of normal, absence of prior nephrectomy, and initiation of treatment within one year of diagnosis. PMID:27217858

  13. A comparative analysis of radiobiological models for cell surviving fractions at high doses.

    Science.gov (United States)

    Andisheh, B; Edgren, M; Belkić, Dž; Mavroidis, P; Brahme, A; Lind, B K

    2013-04-01

    For many years the linear-quadratic (LQ) model has been widely used to describe the effects of total dose and dose per fraction at low-to-intermediate doses in conventional fractionated radiotherapy. Recent advances in stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) have increased the interest in finding a reliable cell survival model, which will be accurate at high doses, as well. Different models have been proposed for improving descriptions of high dose survival responses, such as the Universal Survival Curve (USC), the Kavanagh-Newman (KN) and several generalizations of the LQ model, e.g. the Linear-Quadratic-Linear (LQL) model and the Pade Linear Quadratic (PLQ) model. The purpose of the present study is to compare a number of models in order to find the best option(s) which could successfully be used as a fractionation correction method in SRT. In this work, six independent experimental data sets were used: CHOAA8 (Chinese hamster fibroblast), H460 (non-small cell lung cancer, NSLC), NCI-H841 (small cell lung cancer, SCLC), CP3 and DU145 (human prostate carcinoma cell lines) and U1690 (SCLC). By detailed comparisons with these measurements, the performance of nine different radiobiological models was examined for the entire dose range, including high doses beyond the shoulder of the survival curves. Using the computed and measured cell surviving fractions, comparison of the goodness-of-fit for all the models was performed by means of the reduced χ (2)-test with a 95% confidence interval. The obtained results indicate that models with dose-independent final slopes and extrapolation numbers generally represent better choices for SRT. This is especially important at high doses where the final slope and extrapolation numbers are presently found to play a major role. The PLQ, USC and LQL models have the least number of shortcomings at all doses. The extrapolation numbers and final slopes of these models do not depend on dose. Their asymptotes

  14. Surviving cells after treatment with gemcitabine or 5-fluorouracil for the study of de novo resistance of pancreatic cancer.

    Science.gov (United States)

    Liu, Qing-Hua; Zhang, Jing; Zhao, Chen-Yan; Yu, Dang-Hui; Bu, Hai-Ji; Chen, Ying; Ni, Can-Yong; Zhu, Ming-Hua

    2012-01-01

    One of the hallmarks of pancreatic cancer is its inherent insensitivity to chemotherapy. This study was undertaken to develop a cell model for the study of de novo resistance of pancreatic cancer. The surviving pancreatic cancer cells after a 3-day exposure to gemcitabine or 5-fluorouracil followed by another 7-day recovery were potentially drug-resistant. They had similar morphology and comparable growth and tumorigenic potentials to their untreated parental cells. Repeated subculture affected the cell-cycle profile and growth characteristics of the surviving cells. Our data suggest that surviving pancreatic cancer cells after drug treatment are a useful model for exploring intrinsic resistance.

  15. Predictive factors of survival in patients treated with definitive chemoradiotherapy for squamous cell esophageal carcinoma

    Institute of Scientific and Technical Information of China (English)

    Frédéric Di Fiore; Stéphane Lecleire; Olivier Rigal; Marie-Pierre Galais; Emmanuel Ben Soussan; Isabelle David; Bernard Paillot; Jacques-Henri Jacob; Pierre Michel

    2006-01-01

    AIM: The aim of the study was to evaluate the predictive factors of survival in patients with locally advanced squamous cell esophageal carcinoma (LASCOC) treated with definitive chemoradiotherapy (CRT)regimen based on the 5FU/CDDP combination.METHODS: All patients with LASCOC treated with a definitive CRT using the 5FU/CDDP combination between 1994 and 2000 were retrospectively included.Clinical complete response (CCR) to CRT was assessed by esophageal endoscopy and CT-scan 2 mo after CRT completion. Prognostic factors of survival were assessed using univariate and multivariate analysis by the Cox regression model.RESULTS: A total of 116 patients were included in the study. A CCR to CRT was observed in 86/116 (74.1%).The median survival was 20 mo (range 2-114) and the 5-year survival was 9.4%. Median survival of responder patients to CRT was 25 mo (range 3-114) as compared to 9 mo (range 2-81) in non-responder patients (P <0.001). In univariate analysis, survival was associated with CCR (P < 0.001), WHO performance status < 2 (P= 0.01), tumour length < 6 cm (P = 0.045) and weight loss < 10% was in limit of significance (P = 0.053). In multivariate analysis, survival was dependant to CCR (P< 0.0001), weight loss < 10% (P = 0.034) and WHO performance < 2 (P = 0.046).CONCLUSION: Our results suggest that survival in patients with LASCOC treated with definitive CRT was correlated to CCR, weight loss and WHO performance status.

  16. PIAS1-FAK Interaction Promotes the Survival and Progression of Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Jerfiz D. Constanzo

    2016-05-01

    Full Text Available The sequence of genomic alterations acquired by cancer cells during tumor progression and metastasis is poorly understood. Focal adhesion kinase (FAK is a non-receptor tyrosine kinase that integrates cytoskeleton remodeling, mitogenic signaling and cell survival. FAK has previously been reported to undergo nuclear localization during cell migration, cell differentiation and apoptosis. However, the mechanism behind FAK nuclear accumulation and its contribution to tumor progression has remained elusive. We report that amplification of FAK and the SUMO E3 ligase PIAS1 gene loci frequently co-occur in non-small cell lung cancer (NSCLC cells, and that both gene products are enriched in a subset of primary NSCLCs. We demonstrate that endogenous FAK and PIAS1 proteins interact in the cytoplasm and the cell nucleus of NSCLC cells. Ectopic expression of PIAS1 promotes proteolytic cleavage of the FAK C-terminus, focal adhesion maturation and FAK nuclear localization. Silencing of PIAS1 deregulates focal adhesion turnover, increases susceptibility to apoptosis in vitro and impairs tumor xenograft formation in vivo. Nuclear FAK in turn stimulates gene transcription favoring DNA repair, cell metabolism and cytoskeleton regulation. Consistently, ablation of FAK by CRISPR/Cas9 editing, results in basal DNA damage, susceptibility to ionizing radiation and impaired oxidative phosphorylation. Our findings provide insight into a mechanism regulating FAK cytoplasm-nuclear distribution and demonstrate that FAK activity in the nucleus promotes NSCLC survival and progression by increasing cell-ECM interaction and DNA repair regulation.

  17. Laser Phototherapy Enhances Mesenchymal Stem Cells Survival in Response to the Dental Adhesives

    Directory of Open Access Journals (Sweden)

    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.

  18. Hair Follicle Dermal Sheath Derived Cells Improve Islet Allograft Survival without Systemic Immunosuppression

    Directory of Open Access Journals (Sweden)

    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.

  19. Hair follicle dermal sheath derived cells improve islet allograft survival without systemic immunosuppression.

    Science.gov (United States)

    Wang, Xiaojie; Hao, Jianqiang; Leung, Gigi; Breitkopf, Trisia; Wang, Eddy; Kwong, Nicole; Akhoundsadegh, Noushin; Warnock, Garth L; Shapiro, Jerry; McElwee, Kevin J

    2015-01-01

    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.

  20. Human ribosomal protein L9 is a Bax suppressor that promotes cell survival in yeast.

    Science.gov (United States)

    Eid, Rawan; Sheibani, Sara; Gharib, Nada; Lapointe, Jason F; Horowitz, Avital; Vali, Hojatollah; Mandato, Craig A; Greenwood, Michael T

    2014-05-01

    The identification of a human ribosomal protein L9 (hRPL9) cDNA as a sequence capable of suppressing the lethal effects of heterologously expressed murine Bax in yeast led us to investigate its antiapoptotic potential. Using growth and viability assays, we show that yeast cells heterologously expressing hRPL9 are resistant to the growth inhibitory and lethal effects of exogenously supplied copper, indicating that it has pro-survival properties. To explore potential mechanisms, we used yeast mutants defective in all three types of programmed cell death (apoptosis, necrosis, and autophagy). The ability to retain pro-survival function in all the mutants suggests that hRPL9 may regulate a common pro-death process. In contrast, the yeast RPL9 orthologues, RPL9A and RPL9B, have opposite effects when overexpressed in yeast. In effect, instead of showing resistance to stress, RPL9A and RPL9B overexpressing cells show reduced cell growth. Further analysis indicates that the effects of overexpressed RPL9A and RPL9B are not in themselves lethal, instead, they serve to increase cell doubling time. Thus, yeast RPL9s are more representative of RPs whose extra-ribosomal function is similar to that of tumor suppressors. Taken together, our results demonstrate that RPL9 represents a species- and sequence-specific regulator of cell growth and survival.

  1. Transcorneal electrical stimulation alters morphology and survival of retinal ganglion cells after optic nerve damage.

    Science.gov (United States)

    Henrich-Noack, Petra; Voigt, Nadine; Prilloff, Sylvia; Fedorov, Anton; Sabel, Bernhard A

    2013-05-24

    Traumatic optic nerve injury leads to retrograde death of retinal ganglion cells (RGCs), but transcorneal electrical stimulation (TES) can increase the cell survival rate. To understand the mechanisms and to further define the TES-induced effects we monitored in living animals RGC morphology and survival after optic nerve crush (ONC) in real time by using in vivo confocal neuroimaging (ICON) of the retina. ONC was performed in rats and ICON was performed before crush and on post-lesion days 3, 7 and 15 which allowed us to repeatedly record RGC number and size. TES or sham-stimulation were performed immediately after the crush and on post-injury day 11. Three days after ONC we detected a higher percentage of surviving RGCs in the TES group as compared to sham-treated controls. However, the difference was below significance level on day 7 and disappeared completely by day 15. The death rate was more variable amongst the TES-treated rats than in the control group. Morphological analysis revealed that average cell size changed significantly in the control group but not in stimulated animals and the morphological alterations of surviving neurons were smaller in TES-treated compared to control cells. In conclusion, TES delays post-traumatic cell death significantly. Moreover, we found "responder animals" which also benefited in the long-term from the treatment. Our in vivo cellular imaging results provide evidence that TES reduces ONC-associated neuronal swelling and shrinkage especially in RGCs which survived long-term. Further studies are now needed to determine the differences of responders vs. non-responders.

  2. Expression of proline-rich Akt-substrate PRAS40 in cell survival pathway and carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    Bei HUANG; Gavin PORTER

    2005-01-01

    Aim: To study the expression of proline-rich Akt-substrate PRAS40 in the cell survival pathway and tumor progression. Methods: The effects of three key kinase inhibitors on PRAS40 activity in the cell survival pathway, serum withdrawal,H2O2 and overexpression of Akt were tested. The expression of PRAS40, Akt, Raf and 14-3-3 in normal cells and cancer cell lines was determined by Western blot.Results: The PI3K inhibitors worthmannin and Ly294002, but not rapamycin, completely inhibited the phosphorylation of Akt and PRAS40. The phosphorylation level of Akt decreased after serum withdrawal and treatment with the MEK inhibitor Uo126, but increased after treatment with H2O2 at low concentration, whereas none of these treatments changed PRAS40 activity. 14-3-3 is a PRAS40 binding protein, and the expression of 14-3-3, like that of PRAS40, was higher in HeLa cells than in HEK293 cells; PRAS40 had a stronger phosphorylation activity in A549 and HeLa cancer cells than in HEK293 normal cells. In the breast cancer model (MCF10A/MCF7) and lung cancer model (BEAS/H1198/H1170) we also found the same result: PRAS40 was constitutively active in H1198/H1170 and MCF7 premalignant and malignant cancer cells, but weakly expressed in MCF10A and BEAS normal cell. We also discussed PRAS40 activity in other NSCLC cell lines.Conclusion: The PI3K-Akt survival pathway is the main pathway that PRAS40 is involved in; PRAS40 is a substrate for Akt, but can also be activated by an Aktindependent mechanisms. PRAS40 activation is an early event during breast and lung carcinogenesis.

  3. Neuroendocrine differentiation as a survival prognostic factor in advanced non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Petrović Marina

    2007-01-01

    Full Text Available Beckground/Aim. Neuroendrocine lung tumors are histologically heterogenous group of cancers with different clinical progression. In non-small cell lung cancer (NSCLC neuroendocrine differentiation exists in 10-30% of patients. The aim of this study was to determine the frequency and influence of neuroendocrine differentiation on survival of treated patients with advanced non-small cell lung cancer (NSCLC. Methods. A clinical trial included 158 patients (74% males and 26% females, with the diagnosis of NSCLC, determined by histological verification. The patients were treated by combined chemo - and X-ray therapy in stage III (without pleural effusion or chemotherapy only in stage III (with pleural effusion and stage IV. Chemotherapy was conducted until progression of the disease, but no more than six cycles. When the progression had been noted in stage III (without pleural effusion, the treatment was continued with X-ray therapy. Neuron specific enolase, chromogranin A, as well as synapthophysin expression in tissue examples were determined by immunohistochemical analysis with monoclonal mouse anti-human-bodies. Survival was assessed within a year and two years follow-up examination. Results. A total of 53 patients (34% had NSCLC with neuroendocrine differentiation, confirmed rather in large cell lung cancer and lung adenocarcinoma (66.7% and 40%, respectively. Neuron specific enolase, chromogranin A and synapthophysin expression was noted in 45 (28.5%, 34 (21.5% and 33 (20.1% patients, respectively. The one year and two years follow-up survival periods were confirmed in 39% and 17% of patients respectively. The median survival time in the patients with the neuroendocrine expression as compared to those without the expression was 15.6 vs 10.8 months; one year survival time with the expression compared to those without the expression achieved in 62% vs 27% of the patients, (p < 0.001; a two - year survival time noted in 30% of the patients (p = 0

  4. Increased Survival and Function of Mesenchymal Stem Cell Spheroids Entrapped in Instructive Alginate Hydrogels

    Science.gov (United States)

    Ho, Steve S.; Murphy, Kaitlin C.; Binder, Bernard Y.K.; Vissers, Caroline B.

    2016-01-01

    Mesenchymal stem cell (MSC)-based therapies are under broad investigation for applications in tissue repair but suffer from poor cell persistence and engraftment upon transplantation. MSC spheroids exhibit improved survival, anti-inflammatory, and angiogenic potential in vitro, while also promoting vascularization when implanted in vivo. However, these benefits are lost once cells engage the tissue extracellular matrix and migrate from the aggregate. The efficacy of cell therapy is consistently improved when using engineered materials, motivating the need to investigate the role of biomaterials to instruct spheroid function. In order to assess the contribution of adhesivity on spheroid activity in engineered materials and promote the bone-forming potential of MSCs, we compared the function of MSC spheroids when entrapped in Arg-Gly-Asp (RGD)-modified alginate hydrogels to nonfouling unmodified alginate. Regardless of material, MSC spheroids exhibited reduced caspase activity and greater vascular endothelial growth factor (VEGF) secretion compared with equal numbers of dissociated cells. MSC spheroids in RGD-modified hydrogels demonstrated significantly greater cell survival than spheroids in unmodified alginate. After 5 days in culture, spheroids in RGD-modified gels had similar levels of apoptosis, but more than a twofold increase in VEGF secretion compared with spheroids in unmodified gels. All gels contained mineralized tissue 8 weeks after subcutaneous implantation, and cells entrapped in RGD-modified alginate exhibited greater mineralization versus cells in unmodified gels. Immunohistochemistry confirmed more diffuse osteocalcin staining in gels containing spheroids compared with dissociated controls. This study demonstrates the promise of cell-instructive biomaterials to direct survival and function of MSC spheroids for bone tissue engineering applications. Significance Mesenchymal stem cell (MSC) spheroids exhibit improved therapeutic potential in vitro

  5. The Growing Complexity of Cancer Cell Response to DNA-Damaging Agents: Caspase 3 Mediates Cell Death or Survival?

    Science.gov (United States)

    Mirzayans, Razmik; Andrais, Bonnie; Kumar, Piyush; Murray, David

    2016-05-11

    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.

  6. Molecular Imaging of Stem Cells: Tracking Survival, Biodistribution, Tumorigenicity, and Immunogenicity

    Directory of Open Access Journals (Sweden)

    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.

  7. Androgen receptor signaling is required for androgen-sensitive human prostate cancer cell proliferation and survival

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    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.

  8. Effect of fatty acids on human bone marrow mesenchymal stem cell energy metabolism and survival.

    Science.gov (United States)

    Fillmore, Natasha; Huqi, Alda; Jaswal, Jagdip S; Mori, Jun; Paulin, Roxane; Haromy, Alois; Onay-Besikci, Arzu; Ionescu, Lavinia; Thébaud, Bernard; Michelakis, Evangelos; Lopaschuk, Gary D

    2015-01-01

    Successful stem cell therapy requires the optimal proliferation, engraftment, and differentiation of stem cells into the desired cell lineage of tissues. However, stem cell therapy clinical trials to date have had limited success, suggesting that a better understanding of stem cell biology is needed. This includes a better understanding of stem cell energy metabolism because of the importance of energy metabolism in stem cell proliferation and differentiation. We report here the first direct evidence that human bone marrow mesenchymal stem cell (BMMSC) energy metabolism is highly glycolytic with low rates of mitochondrial oxidative metabolism. The contribution of glycolysis to ATP production is greater than 97% in undifferentiated BMMSCs, while glucose and fatty acid oxidation combined only contribute 3% of ATP production. We also assessed the effect of physiological levels of fatty acids on human BMMSC survival and energy metabolism. We found that the saturated fatty acid palmitate induces BMMSC apoptosis and decreases proliferation, an effect prevented by the unsaturated fatty acid oleate. Interestingly, chronic exposure of human BMMSCs to physiological levels of palmitate (for 24 hr) reduces palmitate oxidation rates. This decrease in palmitate oxidation is prevented by chronic exposure of the BMMSCs to oleate. These results suggest that reducing saturated fatty acid oxidation can decrease human BMMSC proliferation and cause cell death. These results also suggest that saturated fatty acids may be involved in the long-term impairment of BMMSC survival in vivo.

  9. β-Adrenergic Regulation of Cardiac Progenitor Cell Death Versus Survival and Proliferation

    Science.gov (United States)

    Khan, Mohsin; Mohsin, Sadia; Avitabile, Daniele; Siddiqi, Sailay; Nguyen, Jonathan; Wallach, Kathleen; Quijada, Pearl; McGregor, Michael; Gude, Natalie; Alvarez, Roberto; Tilley, Douglas G.; Koch, Walter J.; Sussman, Mark A.

    2013-01-01

    Rationale Short-term β-adrenergic stimulation promotes contractility in response to stress but is ultimately detrimental in the failing heart because of accrual of cardiomyocyte death. Endogenous cardiac progenitor cell (CPC) activation may partially offset cardiomyocyte losses, but consequences of long-term β-adrenergic drive on CPC survival and proliferation are unknown. Objective We sought to determine the relationship between β-adrenergic activity and regulation of CPC function. Methods and Results Mouse and human CPCs express only β2 adrenergic receptor (β2-AR) in conjunction with stem cell marker c-kit. Activation of β2-AR signaling promotes proliferation associated with increased AKT, extracellular signal-regulated kinase 1/2, and endothelial NO synthase phosphorylation, upregulation of cyclin D1, and decreased levels of G protein–coupled receptor kinase 2. Conversely, silencing of β2-AR expression or treatment with β2-antagonist ICI 118, 551 impairs CPC proliferation and survival. β1-AR expression in CPC is induced by differentiation stimuli, sensitizing CPC to isoproterenol-induced cell death that is abrogated by metoprolol. Efficacy of β1-AR blockade by metoprolol to increase CPC survival and proliferation was confirmed in vivo by adoptive transfer of CPC into failing mouse myocardium. Conclusions β-adrenergic stimulation promotes expansion and survival of CPCs through β2-AR, but acquisition of β1-AR on commitment to the myocyte lineage results in loss of CPCs and early myocyte precursors. PMID:23243208

  10. HIF1-Alpha Expression Predicts Survival of Patients with Squamous Cell Carcinoma of the Oral Cavity

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    dos Santos, Marcelo; Mercante, Ana Maria da Cunha; Louro, Iúri Drumond; Gonçalves, Antônio José; de Carvalho, Marcos Brasilino; da Silva, Eloiza Helena Tajara; da Silva, Adriana Madeira Álvares

    2012-01-01

    Background Oral squamous cell carcinoma is an important cause of death and morbidity wordwide and effective prognostic markers are still to be discovered. HIF1α protein is associated with hypoxia response and neovascularization, essential conditions for solid tumors survival. The relationship between HIF1α expression, tumor progression and treatment response in head and neck cancer is still poorly understood. Patients and Methods In this study, we investigated HIF1α expression by immunohistochemistry in tissue microarrays and its relationship with clinical findings, histopathological results and survival of 66 patients with squamous cell carcinoma of the lower mouth. Results Our results demonstrated that high HIF1α expression is associated with local disease-free survival, independently from the choice of treatment. Furthermore, high expression of HIF1α in patients treated with postoperative radiotherapy was associated with survival, therefore being a novel prognostic marker in squamous cell carcinoma of the mouth. Additionally, our results showed that MVD was associated with HIF1α expression and local disease relapse. Conclusion These findings suggest that HIF1α expression can be used as a prognostic marker and predictor of postoperative radiotherapy response, helping the oncologist choose the best treatment for each patient. PMID:23028863

  11. Osteocalcin protects pancreatic beta cell function and survival under high glucose conditions

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    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

  12. Oral cancer/endothelial cell fusion experiences nuclear fusion and acquisition of enhanced survival potential.

    Science.gov (United States)

    Song, Kai; Song, Yong; Zhao, Xiao-Ping; Shen, Hui; Wang, Meng; Yan, Ting-Lin; Liu, Ke; Shang, Zheng-Jun

    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.

  13. The Par3 polarity protein is an exocyst receptor essential for mammary cell survival

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    Ahmed, Syed Mukhtar; Macara, Ian G.

    2017-01-01

    The exocyst is an essential component of the secretory pathway required for delivery of basolateral proteins to the plasma membranes of epithelial cells. Delivery occurs adjacent to tight junctions (TJ), suggesting that it recognizes a receptor at this location. However, no such receptor has been identified. The Par3 polarity protein associates with TJs but has no known function in membrane traffic. We now show that, unexpectedly, Par3 is essential for mammary cell survival. Par3 silencing causes apoptosis, triggered by phosphoinositide trisphosphate depletion and decreased Akt phosphorylation, resulting from failure of the exocyst to deliver basolateral proteins to the cortex. A small region of PAR3 binds directly to Exo70 and is sufficient for exocyst docking, membrane-protein delivery and cell survival. PAR3 lacking this domain can associate with the cortex but cannot support exocyst function. We conclude that Par3 is the long-sought exocyst receptor required for targeted membrane-protein delivery. PMID:28358000

  14. Evidence for the involvement of NOD2 in regulating colonic epithelial cell growth and survival

    Institute of Scientific and Technical Information of China (English)

    Sheena M Cruickshank; Louise Wakenshaw; John Cardone; Peter D Howdle; Peter J Murray; Simon R Carding

    2008-01-01

    AIM: To investigate the function of NOD2 in colonic epithelial cells (CEC).METHODS: A combination of in vivo and in vitro analyses of epithelial cell turnover in the presence and absence of a functional NOD2 protein and, in response to enteric Salmonella typhimurium infection, were used. shRNA interference was also used to investigate the consequences of knocking down NOD2 gene expression on the growth and survival of colorectal carcinoma cell lines.RESULTS: In the colonic mucosa the highest levels of NOD2 expression were in proliferating crypt epithelial cells. Muramyl dipeptide (MDP), that is recognized by NOD2, promoted CEC growth in vitro. By contrast, the growth of NOD2-deficient CECs was impaired. In vivo CEC proliferation was also reduced and apoptosis increased in Nod2-/- mice, which were also evident following enteric Salmonella infection. Furthermore, neutralization of NOD2 mRNA expression in human colonic carcinoma cells by shRNA interference resulted in decreased survival due to increased levels of apoptosis.CONCLUSION: These findings are consistent with the involvement of NOD2 protein in promoting CEC growth and survival. Defects in proliferation by CECs in cases of CD may contribute to the underlying pathology of disrupted intestinal homeostasis and excessive inflammation.

  15. Autologous Dendritic Cells Prolong Allograft Survival Through Tmem176b-Dependent Antigen Cross-Presentation

    Science.gov (United States)

    Charnet, P.; Savina, A.; Tilly, G.; Gautreau, L.; Carretero-Iglesia, L.; Beriou, G.; Cebrian, I.; Cens, T.; Hepburn, L.; Chiffoleau, E.; Floto, R. A.; Anegon, I.; Amigorena, S.; Hill, M.; Cuturi, M. C.

    2015-01-01

    The administration of autologous (recipient-derived) tolerogenic dendritic cells (ATDCs) is under clinical evaluation. However, the molecular mechanisms by which these cells prolong graft survival in a donor-specific manner is unknown. Here, we tested mouse ATDCs for their therapeutic potential in a skin transplantation model. ATDC injection in combination with anti-CD3 treatment induced the accumulation of CD8+CD11c+ T cells and significantly prolonged allograft survival. TMEM176B is an intracellular protein expressed in ATDCs and initially identified in allograft tolerance. We show that Tmem176b−/− ATDCs completely failed to trigger both phenomena but recovered their effect when loaded with donor peptides before injection. These results strongly suggested that ATDCs require TMEM176B to cross-present antigens in a tolerogenic fashion. In agreement with this, Tmem176b−/− ATDCs specifically failed to cross-present male antigens or ovalbumin to CD8+ T cells. Finally, we observed that a Tmem176b-dependent cation current controls phagosomal pH, a critical parameter in cross-presentation. Thus, ATDCs require TMEM176B to cross-present donor antigens to induce donor-specific CD8+CD11c+ T cells with regulatory properties and prolong graft survival. PMID:24731243

  16. Stem cell factor expression after renal ischemia promotes tubular epithelial survival.

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    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.

  17. Invariant NKT cells require autophagy to coordinate proliferation and survival signals during differentiation.

    Science.gov (United States)

    Pei, Bo; Zhao, Meng; Miller, Brian C; Véla, Jose Luis; Bruinsma, Monique W; Virgin, Herbert W; Kronenberg, Mitchell

    2015-06-15

    Autophagy regulates cell differentiation, proliferation, and survival in multiple cell types, including cells of the immune system. In this study, we examined the effects of a disruption of autophagy on the differentiation of invariant NKT (iNKT) cells. Using mice with a T lymphocyte-specific deletion of Atg5 or Atg7, two members of the macroautophagic pathway, we observed a profound decrease in the iNKT cell population. The deficit is cell-autonomous, and it acts predominantly to reduce the number of mature cells, as well as the function of peripheral iNKT cells. In the absence of autophagy, there is reduced progression of iNKT cells in the thymus through the cell cycle, as well as increased apoptosis of these cells. Importantly, the reduction in Th1-biased iNKT cells is most pronounced, leading to a selective reduction in iNKT cell-derived IFN-γ. Our findings highlight the unique metabolic and genetic requirements for the differentiation of iNKT cells.

  18. Survival advantages conferred to colon cancer cells by E-selectin-induced activation of the PI3K-NFκB survival axis downstream of Death receptor-3

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    Paquet Éric R

    2011-07-01

    Full Text Available Abstract Background Extravasation of circulating cancer cells is a key event of metastatic dissemination that is initiated by the adhesion of cancer cells to endothelial cells. It requires interactions between adhesion receptors on endothelial cells and their counter-receptors on cancer cells. Notably, E-selectin, a major endothelial adhesion receptor, interacts with Death receptor-3 present on metastatic colon carcinoma cells. This interaction confers metastatic properties to colon cancer cells by promoting the adhesion of cancer cells to endothelial cells and triggering the activation of the pro-migratory p38 and pro-survival ERK pathways in the cancer cells. In the present study, we investigated further the mechanisms by which the E-selectin-activated pathways downstream of DR3 confer a survival advantage to colon cancer cells. Methods Cell survival has been ascertained by using the WST-1 assay and by evaluating the activation of the PI3 kinase/NFκB survival axis. Apoptosis has been assayed by determining DNA fragmentation by Hoechst staining and by measuring cleavage of caspases-8 and -3. DR3 isoforms have been identified by PCR. For more precise quantification, targeted PCR reactions were carried out, and the amplified products were analyzed by automated chip-based microcapillary electrophoresis on an Agilent 2100 Bioanalyzer instrument. Results Interaction between DR3-expressing HT29 colon carcinoma cells and E-selectin induces the activation of the PI3K/Akt pathway. Moreover, p65/RelA, the anti-apoptotic subunit of NFκB, is rapidly translocated to the nucleus in response to E-selectin. This translocation is impaired by the PI3K inhibitor LY294002. Furthermore, inhibition of the PI3K/Akt pathway increases the cleavage of caspase 8 in colon cancer cells treated with E-selectin and this effect is still further increased when both ERK and PI3K pathways are concomitantly inhibited. Intriguingly, metastatic colon cancer cell lines such as HT

  19. Regulation of pancreatic β-cell survival by nitric oxide: clinical relevance.

    Science.gov (United States)

    Bedoya, Francisco J; Salguero-Aranda, Carmen; Cahuana, Gladys M; Tapia-Limonchi, Rafael; Soria, Bernat; Tejedo, Juan R

    2012-01-01

    The reduction of pancreatic β-cell mass is an important factor in the development of type 1 and type 2 diabetes. Understanding the mechanisms that regulate the maintenance of pancreatic β-cell mass as well as β-cell death is necessary for the establishment of therapeutic strategies. In this context, nitric oxide (NO) is a diatomic, gaseous, highly reactive molecule with biological activity that participates in the regulation of pancreatic β-cell mass. Two types of cellular responses can be distinguished depending on the level of NO production. First, pancreatic β-cells exposed to inflammatory cytokines, lipid stress or hyperglycaemia produce high concentrations of NO, mainly due to the activation of inducible NO synthase (iNOS), thus promoting cell death. Meanwhile, under homeostatic conditions, low concentrations of NO, constitutively produced by endothelial NO synthase (eNOS), promote cell survival. Here, we will discuss the current knowledge of the NO-dependent mechanisms activated during cellular responses, emphasizing those related to the regulation of cell survival.

  20. Staying in Shape: the Impact of Cell Shape on Bacterial Survival in Diverse Environments.

    Science.gov (United States)

    Yang, Desirée C; Blair, Kris M; Salama, Nina R

    2016-03-01

    Bacteria display an abundance of cellular forms and can change shape during their life cycle. Many plausible models regarding the functional significance of cell morphology have emerged. A greater understanding of the genetic programs underpinning morphological variation in diverse bacterial groups, combined with assays of bacteria under conditions that mimic their varied natural environments, from flowing freshwater streams to diverse human body sites, provides new opportunities to probe the functional significance of cell shape. Here we explore shape diversity among bacteria, at the levels of cell geometry, size, and surface appendages (both placement and number), as it relates to survival in diverse environments. Cell shape in most bacteria is determined by the cell wall. A major challenge in this field has been deconvoluting the effects of differences in the chemical properties of the cell wall and the resulting cell shape perturbations on observed fitness changes. Still, such studies have begun to reveal the selective pressures that drive the diverse forms (or cell wall compositions) observed in mammalian pathogens and bacteria more generally, including efficient adherence to biotic and abiotic surfaces, survival under low-nutrient or stressful conditions, evasion of mammalian complement deposition, efficient dispersal through mucous barriers and tissues, and efficient nutrient acquisition.

  1. Effects of Thapsigargin on the Proliferation and Survival of Human Rheumatoid Arthritis Synovial Cells

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    Hui Wang

    2014-01-01

    Full Text Available A series of experiments have been carried out to investigate the effects of different concentrations of thapsigargin (0, 0.001, 0.1, and 1 μM on the proliferation and survival of human rheumatoid arthritis synovial cells (MH7A. The results showed that thapsigargin can block the cell proliferation in human rheumatoid arthritis synovial cells in a time- and dose-dependent manner. Results of Hoechst staining suggested that thapsigargin may induce cell apoptosis in MH7A cells in a time- and dose-dependent manner, and the percentages of cell death reached 44.6% at thapsigargin concentration of 1 μM treated for 4 days compared to the control. The protein and mRNA levels of cyclin D1 decreased gradually with the increasing of thapsigargin concentration and treatment times. Moreover, the protein levels of mTORC1 downstream indicators pS6K and p4EBP-1 were reduced by thapsigargin treatment at different concentrations and times, which should be responsible for the reduced cyclin D1 expressions. Our results revealed that thapsigargin may effectively impair the cell proliferation and survival of MH7A cells. The present findings will help to understand the molecular mechanism of fibroblast-like synoviocytes proliferations and suggest that thapsigargin is of potential for the clinical treatment of rheumatoid arthritis.

  2. discs large regulates somatic cyst cell survival and expansion in Drosophila testis

    Institute of Scientific and Technical Information of China (English)

    Fani Papagiannouli; Bernard M Mechler

    2009-01-01

    Gonad development requires a coordinated snma-germline interaction that ensures renewal and differentiation of germline and somatic stem cells to ultimately produce mature gametes. The Drosophila tumour suppressor gene discs sion, and formation of neuromuscular junctions. Here, we report the role of dig in testis development and its critical function in somatic cyst cells (SCCs). In these cells dig is primarily required for their survival and expansion, and contributes to spermatocyte cyst differentiation. Cell death primarily occurred in SCCs at the end of spermatogo-nial amplification at a time when Dig becomes restricted in wild-type (wt) testes to the distal somatic cells capping the growing spermatocyte cysts. RNAi depletion of dig transcripts in early SCCs fully prevented testis development, whereas depletion in late SCCs resulted in a breakdown of spermatocyte cyst structure and germ cell individualiza-tion. Specific dig expression in SCCs resulted in developmental rescue of dig mutant testes, whereas its expression in germ cells exerted no such effect, dig overexpression in wt testes led to spermatocyte cyst expansion at the expense of spermatogonial cysts. Our data demonstrate that dig is essentially required in SCCs for their survival, expansion, and differentiation, and for the encapsulation of the germline cells.

  3. The influence of social support on hematopoietic stem cell transplantation survival: a systematic review of literature.

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    Sara Beattie

    Full Text Available BACKGROUND: Hematopoietic Stem cell Transplantation (HSCT can negatively impact the psychosocial well-being of the patient. Social support is a complex term that has been variably used to encompass perceived and objective support, including caregiver presence. Social support has been associated with superior psychosocial outcomes; however the influence of social support on HSCT survival remains unclear. We sought to summarize the literature on the influence of social support on HSCT survival. METHODS: MEDLINE, EMBASE, COCHRANE, CINAHL, AND PSYCINFO WERE SEARCHED USING THE FOLLOWING SEARCH CATEGORIES/CONCEPTS: 1 HSCT, 2 Social support, 3 Caregiver, 4 Survival, and 5 Treatment outcomes. RESULTS: We identified 6 relevant studies: 4 publications, 1 dissertation, and 1 abstract. Three studies were retrospective and 3, prospective. Sample size ranged between 92-272 with a mean/median patient age between 30-55 yrs. The duration of follow-up ranged between 13.3-48 months. Social support was measured inconsistently: 2 by retrospective investigator assessment, 2 as patients' perceived support, 1 as caregiver presence, and 1 included caregiver presence and retrospective investigator assessment. The 4 published studies and 1 abstract demonstrate an association between better social support and survival. However, the unpublished dissertation, with the largest sample size found no association. CONCLUSIONS: There is a paucity of evidence examining social support with HSCT survival. Available studies are older, with the most recent publication in 2005. A heterogeneous group of HSCT patients were studied with variable follow-up times. Further, covariates were variably considered in HSCT survival analyses and we suggest that there may be publication bias, given the negative unpublished study with the largest sample size. Prospective studies using validated scales are necessary to better assess the influence of social support on HSCT mortality. Given the potential

  4. Associations of ATM Polymorphisms With Survival in Advanced Esophageal Squamous Cell Carcinoma Patients Receiving Radiation Therapy

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    Du, Zhongli [State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Department of Etiology and Carcinogenesis (Beijing Key Laboratory for Carcinogenesis and Cancer Prevention), Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Zhang, Wencheng [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Zhou, Yuling; Yu, Dianke; Chen, Xiabin; Chang, Jiang; Qiao, Yan; Zhang, Meng; Huang, Ying; Wu, Chen [State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Department of Etiology and Carcinogenesis (Beijing Key Laboratory for Carcinogenesis and Cancer Prevention), Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Xiao, Zefen, E-mail: xiaozefen@sina.com [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Tan, Wen, E-mail: tanwen@cicams.ac.cn [State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Department of Etiology and Carcinogenesis (Beijing Key Laboratory for Carcinogenesis and Cancer Prevention), Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); and others

    2015-09-01

    Purpose: To investigate whether single nucleotide polymorphisms (SNPs) in the ataxia telangiectasia mutated (ATM) gene are associated with survival in patients with esophageal squamous cell carcinoma (ESCC) receiving radiation therapy or chemoradiation therapy or surgery only. Methods and Materials: Four tagSNPs of ATM were genotyped in 412 individuals with clinical stage III or IV ESCC receiving radiation therapy or chemoradiation therapy, and in 388 individuals with stage I, II, or III ESCC treated with surgery only. Overall survival time of ESCC among different genotypes was estimated by Kaplan-Meier plot, and the significance was examined by log-rank test. The hazard ratios (HRs) and 95% confidence intervals (CIs) for death from ESCC among different genotypes were computed by a Cox proportional regression model. Results: We found 2 SNPs, rs664143 and rs664677, associated with survival time of ESCC patients receiving radiation therapy. Individuals with the rs664143A allele had poorer median survival time compared with the rs664143G allele (14.0 vs 20.0 months), with the HR for death being 1.45 (95% CI 1.12-1.89). Individuals with the rs664677C allele also had worse median survival time than those with the rs664677T allele (14.0 vs 23.5 months), with the HR of 1.57 (95% CI 1.18-2.08). Stratified analysis showed that these associations were present in both stage III and IV cancer and different radiation therapy techniques. Significant associations were also found between the SNPs and locosregional progression or progression-free survival. No association between these SNPs and survival time was detected in ESCC patients treated with surgery only. Conclusion: These results suggest that the ATM polymorphisms might serve as independent biomarkers for predicting prognosis in ESCC patients receiving radiation therapy.

  5. DNA Repair Gene Polymorphisms in Relation to Non-Small Cell Lung Cancer Survival

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    Yuliang Su

    2015-07-01

    Full Text Available Background: Single nucleotide polymorphisms (SNPs in the DNA repair genes are suspected to be related to the survival of lung cancer patients due to their possible influence on DNA repair capacity (DRC. However, the study results are inconsistent. Methods: A follow-up study of 610 non-small cell lung cancer (NSCLC patients was conducted to investigate genetic polymorphisms associated with the DNA repair genes in relation to NSCLC survival; 6 SNPs were genotyped, including XRCC1 (rs25487 G>A, hOGG1 (rs1052133 C>G, MUTYH (rs3219489 G>C, XPA (rs1800975 G>A, ERCC2 (rs1799793 G>A and XRCC3 (rs861539 C>T. Kaplan-Meier survival curve and Cox proportional hazards regression analyses were performed. SNP-SNP interaction was also examined using the survival tree analysis. Results: Advanced disease stage and older age at diagnosis were associated with poor prognosis of NSCLC. Patients with the variant ‘G' allele of hOGG1 rs1052133 had poor overall survival compared with those with the homozygous wild ‘CC' genotype, especially in female patients, adenocarcinoma histology, early stage, light smokers and without family history of cancer. For never smoking female lung cancer patients, individuals carrying homozygous variant ‘AA' genotype of XPA had shorter survival time compared to those with wild ‘G' alleles. Furthermore, females carrying homozygous variant XPA and hOGG1 genotypes simultaneously had 2.78-fold increased risk for death. Among all 6 polymorphisms, the homozygous variant ‘AA' of XPA carriers had poor prognosis compared to the carriers of wild ‘G' alleles of XPA together with other base excision repair (BER polymorphisms. Conclusions: Besides disease stage and age, the study found DNA repair gene polymorphisms were associated with lung cancer survival.

  6. Corticosteroids reverse cytokine-induced block of survival and differentiation of oligodendrocyte progenitor cells from rats

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    Marx Romy

    2008-09-01

    Full Text Available Abstract Background Periventricular leukomalacia (PVL is a frequent complication of preterm delivery. Proinflammatory cytokines, such as interferon-γ (IFN-γ and tumor necrosis factor α (TNF-α released from astrocytes and microglia activated by infection or ischemia have previously been shown to impair survival and maturation of oligodendrocyte progenitors and could thus be considered as potential factors contributing to the generation of this disease. The first goal of the present study was to investigate whether exposure of oligodendrocyte precursors to these cytokines arrests the maturation of ion currents in parallel to its effects on myelin proteins and morphological maturation. Secondly, in the search for agents, that can protect differentiating oligodendrocyte precursor cells from cytokine-induced damage we investigated effects of coapplications of corticosteroids with proinflammatory cytokines on the subsequent survival and differentiation of oligodendrocyte progenitor cells. Methods To exclude influences from factors released from other cell types purified cultures of oligodendrocyte precursors were exposed to cytokines and/or steroids and allowed to differentiate for further 6 days in culture. Changes in membrane surface were investigated with capacitance recordings and Scanning Ion Conductance Microscopy. Na+- and K+- currents were investigated using whole cell patch clamp recordings. The expression of myelin specific proteins was investigated using western blots and the precursor cells were identified using immunostaining with A2B5 antibodies. Results Surviving IFN-γ and TNF-α treated cells continued to maintain voltage-activated Na+- and K+ currents characteristic for the immature cells after 6 days in differentiation medium. Corticosterone, dihydrocorticosterone and, most prominently dexamethasone, counteracted the deleterious effects of IFN-γ and TNF-α on cell survival, A2B5-immunostaining and expression of myelin basic

  7. Modulation of Dendritic Cell Responses by Parasites: A Common Strategy to Survive

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    César A. Terrazas

    2010-01-01

    Full Text Available Parasitic infections are one of the most important causes of morbidity and mortality in our planet and the immune responses triggered by these organisms are critical to determine their outcome. Dendritic cells are key elements for the development of immunity against parasites; they control the responses required to eliminate these pathogens while maintaining host homeostasis. However, there is evidence showing that parasites can influence and regulate dendritic cell function in order to promote a more permissive environment for their survival. In this review we will focus on the strategies protozoan and helminth parasites have developed to interfere with dendritic cell activities as well as in the possible mechanisms involved.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    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....... The mechanisms inducing this lipototoxicity involved increased production of reactive oxygen species (ROS). In this review, regulation of GLP-1-secreting cells is discussed, with a focus on the mechanisms underlying GLP-1 secretion, long-term regulation of growth, differentiation and survival under normal...

  9. Model for Osteosarcoma-9 as a potent factor in cell survival and resistance to apoptosis

    Science.gov (United States)

    Vourvouhaki, Ekaterini; Carvalho, Carla; Aguiar, Paulo

    2007-07-01

    In this paper we use a simple model to explore the function of the gene Osteosarcoma-9 (OS-9). We are particularly interested in understanding the role of this gene as a potent anti-apoptotic factor. The theoretical description is constrained by experimental data from induction of apoptosis in cells where OS-9 is overexpressed. The data available suggest that OS-9 promotes cell viability and confers resistance to apoptosis, potentially implicating OS-9 in the survival of cancer cells. Three different apoptosis-inducing mechanisms were tested and are modeled here. A more complex and realistic model is also discussed.

  10. Oral cancer/endothelial cell fusion experiences nuclear fusion and acquisition of enhanced survival potential

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. Differing Requirements for MALT1 Function in Peripheral B Cell Survival and Differentiation.

    Science.gov (United States)

    Lee, Peishan; Zhu, Zilu; Hachmann, Janna; Nojima, Takuya; Kitamura, Daisuke; Salvesen, Guy; Rickert, Robert C

    2017-02-01

    During a T cell-dependent immune response, formation of the germinal center (GC) is essential for the generation of high-affinity plasma cells and memory B cells. The canonical NF-κB pathway has been implicated in the initiation of GC reaction, and defects in this pathway have been linked to immune deficiencies. The paracaspase MALT1 plays an important role in regulating NF-κB activation upon triggering of Ag receptors. Although previous studies have reported that MALT1 deficiency abrogates the GC response, the relative contribution of B cells and T cells to the defective phenotype remains unclear. We used chimeric mouse models to demonstrate that MALT1 function is required in B cells for GC formation. This role is restricted to BCR signaling where MALT1 is critical for B cell proliferation and survival. Moreover, the proapoptotic signal transmitted in the absence of MALT1 is dominant to the prosurvival effects of T cell-derived stimuli. In addition to GC B cell differentiation, MALT1 is required for plasma cell differentiation, but not mitogenic responses. Lastly, we show that ectopic expression of Bcl-2 can partially rescue the GC phenotype in MALT1-deficient animals by prolonging the lifespan of BCR-activated B cells, but plasma cell differentiation and Ab production remain defective. Thus, our data uncover previously unappreciated aspects of MALT1 function in B cells and highlight its importance in humoral immunity.

  12. Bmi1 overexpression in the cerebellar granule cell lineage of mice affects cell proliferation and survival without initiating medulloblastoma formation

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    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.

  13. Rapamycin increases RSV RNA levels and survival of RSV-infected dendritic cell depending on T cell contact.

    Science.gov (United States)

    do Nascimento de Freitas, Deise; Gassen, Rodrigo Benedetti; Fazolo, Tiago; Souza, Ana Paula Duarte de

    2016-10-01

    The macrolide rapamycin inhibits mTOR (mechanist target of rapamycin) function and has been broadly used to unveil the role of mTOR in immune responses. Inhibition of mTOR on dendritic cells (DC) can influence cellular immune response and the survival of DC. RSV is the most common cause of hospitalization in infants and is a high priority candidate to vaccine development. In this study we showed that rapamycin treatment on RSV-infected murine bone marrow-derived DC (BMDC) decreases the frequency of CD8(+)CD44(high) T cells. However, inhibition of mTOR on RSV-infected BMDC did not modify the activation phenotype of these cells. RSV-RNA levels increase when infected BMDC were treated with rapamycin. Moreover, we observed that rapamycin diminishes apoptosis cell death of RSV-infected BMDC co-culture with T cells and this effect was abolished when the cells were co-cultured in a transwell system that prevents cell-to-cell contact or migration. Taken together, these data indicate that rapamycin treatment present a toxic effect on RSV-infected BMDC increasing RSV-RNA levels, affecting partially CD8 T cell differentiation and also increasing BMDC survival in a mechanism dependent on T cell contact.

  14. Notch1 regulated autophagy controls survival and suppressor activity of activated murine T-regulatory cells

    Science.gov (United States)

    Marcel, Nimi; Sarin, Apurva

    2016-01-01

    Cell survival is one of several processes regulated by the Notch pathway in mammalian cells. Here we report functional outcomes of non-nuclear Notch signaling to activate autophagy, a conserved cellular response to nutrient stress, regulating survival in murine natural T-regulatory cells (Tregs), an immune subset controlling tolerance and inflammation. Induction of autophagy required ligand-dependent, Notch intracellular domain (NIC) activity, which controlled mitochondrial organization and survival of activated Tregs. Consistently, NIC immune-precipitated Beclin and Atg14, constituents of the autophagy initiation complex. Further, ectopic expression of an effector of autophagy (Atg3) or recombinant NIC tagged to a nuclear export signal (NIC-NES), restored autophagy and suppressor function in Notch1-/- Tregs. Furthermore, Notch1 deficiency in the Treg lineage resulted in immune hyperactivity, implicating Notch activity in Treg homeostasis. Notch1 integration with autophagy, revealed in these experiments, holds implications for Notch regulated cell-fate decisions governing differentiation. DOI: http://dx.doi.org/10.7554/eLife.14023.001 PMID:27267497

  15. Inhibition of Bcl-2 or IAP proteins does not provoke mutations in surviving cells

    Energy Technology Data Exchange (ETDEWEB)

    Shekhar, Tanmay M. [Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora 3083 (Australia); Green, Maja M. [Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora 3083 (Australia); Department of Anatomy & Neuroscience, The University of Melbourne, Parkville 3010 (Australia); Rayner, David M.; Miles, Mark A.; Cutts, Suzanne M. [Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora 3083 (Australia); Hawkins, Christine J., E-mail: c.hawkins@latrobe.edu.au [Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora 3083 (Australia)

    2015-07-15

    Graphical abstract: - Highlights: • Mutagenicities of anti-cancer drugs were tested using HPRT, γH2AX and comet assays. • TRAIL, doxorubicin and etoposide were more mutagenic than BH3- or Smac-mimetics. • Physiologically achievable levels of the BH3-mimetic ABT-737 were not mutagenic. • High concentrations of ABT-737 provoked mutations via an off-target mechanism. • Even very high concentrations of IAP antagonists were not mutagenic. - Abstract: Chemotherapy and radiotherapy can cause permanent damage to the genomes of surviving cells, provoking severe side effects such as second malignancies in some cancer survivors. Drugs that mimic the activity of death ligands, or antagonise pro-survival proteins of the Bcl-2 or IAP families have yielded encouraging results in animal experiments and early phase clinical trials. Because these agents directly engage apoptosis pathways, rather than damaging DNA to indirectly provoke tumour cell death, we reasoned that they may offer another important advantage over conventional therapies: minimisation or elimination of side effects such as second cancers that result from mutation of surviving normal cells. Disappointingly, however, we previously found that concentrations of death receptor agonists like TRAIL that would be present in vivo in clinical settings provoked DNA damage in surviving cells. In this study, we used cell line model systems to investigate the mutagenic capacity of drugs from two other classes of direct apoptosis-inducing agents: the BH3-mimetic ABT-737 and the IAP antagonists LCL161 and AT-406. Encouragingly, our data suggest that IAP antagonists possess negligible genotoxic activity. Doses of ABT-737 that were required to damage DNA stimulated Bax/Bak-independent signalling and exceeded concentrations detected in the plasma of animals treated with this drug. These findings provide hope that cancer patients treated by BH3-mimetics or IAP antagonists may avoid mutation-related illnesses that afflict

  16. Survivability of Salmonella cells in popcorn after microwave oven and conventional cooking.

    Science.gov (United States)

    Anaya, I; Aguirrezabal, A; Ventura, M; Comellas, L; Agut, M

    2008-01-01

    The survivability of Salmonella cells in popcorn preparation was determined for two distinct cooking methods. The first method used a standard microwave oven. The second method used conventional cooking in a pan. Prior to thermal processing in independent experiments, 12 suspensions in a range between 1x10(3) and 8x10(6) colony-forming units (CFU) per gram of Salmonella cells were inoculated in both raw microwave popcorn and conventional corn kernels. The influence of the initial concentration of Salmonella cells in the raw products and the lethal effects on Salmonella by thermal treatments for cooking were studied. Survival of Salmonella cells was determined in the thermally processed material by pre-enrichment and enrichment in selective medium, in accordance with the legislation for expanded cereals and cereals in flakes. Viable experimental contaminants were recovered from the conventionally cooked popcorn with initial inoculation concentrations of 9x10(4)cells/g or greater. Salmonella cell viability was significantly reduced after microwave oven treatment, with recoveries only from initial concentrations of 2x10(6)cells/g or superior.

  17. Survival of Dental Pulp Stem Cells: The effect of Soymilk and Milk

    Directory of Open Access Journals (Sweden)

    Fatemeh Sholehvar

    2015-11-01

    Full Text Available Background & Objectives: Dental pulp stem cells (DPSCs are alternate source of mesenchymal stem cells. Subsequent to tooth avulsion and fracture, DPSCs can play a prominent role in tissue regeneration. This study was conducted to evaluate the effect of soymilk and milk on survival of dental pulp stem cells. Materials & Methods: DPSCs were isolated from 16 freshly extracted incisors of 5 rabbits. The 3rd passage was seeded in 24 well plates, and after 3 days, soymilk, cow milk, HBSS, and distilled water were replaced with culture media. After 45 minutes, 1.5, 3, and 6 hours, the viability of DPSCs were investigated. Mesenchymal nature of stem cells was investigated by RT-PCR. The cell viability was determined by Trypan blue exclusion. Karyotyping was done to evaluate the cytogenetic stability of cells.  Results: The viability of DPSCs in all media were significantly more than distilled water at all intervals. After 6 h, the viability of DPSCs in soymilk, cow milk, and HBSS were 100,000±0.00, 100,000±0.00, and 74.74±5.70, respectively. After 6 h, both soymilk and cow milk maintained cells significantly better than HBSS. Conclusion: Like cow milk, soymilk is a suitable alternative transfer media for avulsed and broken teeth that can increase the survival of DPSCs.   

  18. Expression of HSF2 decreases in mitosis to enable stress-inducible transcription and cell survival.

    Science.gov (United States)

    Elsing, Alexandra N; Aspelin, Camilla; Björk, Johanna K; Bergman, Heidi A; Himanen, Samu V; Kallio, Marko J; Roos-Mattjus, Pia; Sistonen, Lea

    2014-09-15

    Unless mitigated, external and physiological stresses are detrimental for cells, especially in mitosis, resulting in chromosomal missegregation, aneuploidy, or apoptosis. Heat shock proteins (Hsps) maintain protein homeostasis and promote cell survival. Hsps are transcriptionally regulated by heat shock factors (HSFs). Of these, HSF1 is the master regulator and HSF2 modulates Hsp expression by interacting with HSF1. Due to global inhibition of transcription in mitosis, including HSF1-mediated expression of Hsps, mitotic cells are highly vulnerable to stress. Here, we show that cells can counteract transcriptional silencing and protect themselves against proteotoxicity in mitosis. We found that the condensed chromatin of HSF2-deficient cells is accessible for HSF1 and RNA polymerase II, allowing stress-inducible Hsp expression. Consequently, HSF2-deficient cells exposed to acute stress display diminished mitotic errors and have a survival advantage. We also show that HSF2 expression declines during mitosis in several but not all human cell lines, which corresponds to the Hsp70 induction and protection against stress-induced mitotic abnormalities and apoptosis.

  19. Mild Nutrient Starvation Triggers the Development of a Small-Cell Survival Morphotype in Mycobacteria.

    Science.gov (United States)

    Wu, Mu-Lu; Gengenbacher, Martin; Dick, Thomas

    2016-01-01

    Mycobacteria, generally believed to be non-sporulating, are well known to survive shock starvation in saline for extended periods of time in a non-replicating state without any apparent morphological changes. Here, we uncover that mycobacteria can undergo cellular differentiation by exposing Mycobacterium smegmatis to mild starvation conditions. Traces of various carbon sources in saline triggered the development of a novel small resting cell (SMRC) morphotype. Development of SMRCs could also be observed for other mycobacteria, suggesting evolutionary conservation of this differentiation pathway. Fluorescence microscopic analyses showed that development of SMRCs progresses via septated, multi-nucleoided cell intermediates, which divide to generate mono-nucleoided SMRCs. Intriguingly, saline shock-starved large resting cells (LARCs), which did not show cell size or surface changes when observed by scanning electron microscopy, remodeled their internal structure to septated, multi-nucleoided cells, similar to the intermediates seen during differentiation to SMRCs. Our results suggest that mycobacteria harbor a starvation-induced differentiation program in which at first septated, multi-nucleoided cells are generated. Under zero-nutrient conditions bacteria terminate development at this stage as LARCs. In the presence of traces of a carbon source, these multi-nucleoided cells continue differentiation into mono-nucleoided SMRCs. Both SMRCs and LARCs exhibited extreme antibiotic tolerance. SMRCs showed increased long-term starvation survival, which was associated with the presence of lipid inclusion bodies.

  20. C/EBPβ regulates transcription factors critical for proliferation and survival of multiple myeloma cells

    Science.gov (United States)

    Pal, Rekha; Janz, Martin; Galson, Deborah L.; Gries, Margarete; Li, Shirong; Jöhrens, Korinna; Anagnostopoulos, Ioannis; Dörken, Bernd; Mapara, Markus Y.; Borghesi, Lisa; Kardava, Lela; Roodman, G. David; Milcarek, Christine

    2009-01-01

    CCAAT/enhancer-binding protein β (C/EBPβ), also known as nuclear factor–interleukin-6 (NF-IL6), is a transcription factor that plays an important role in the regulation of growth and differentiation of myeloid and lymphoid cells. Mice deficient in C/EBPβ show impaired generation of B lymphocytes. We show that C/EBPβ regulates transcription factors critical for proliferation and survival in multiple myeloma. Multiple myeloma cell lines and primary multiple myeloma cells strongly expressed C/EBPβ, whereas normal B cells and plasma cells had little or no detectable levels of C/EBPβ. Silencing of C/EBPβ led to down-regulation of transcription factors such as IRF4, XBP1, and BLIMP1 accompanied by a strong inhibition of proliferation. Further, silencing of C/EBPβ led to a complete down-regulation of antiapoptotic B-cell lymphoma 2 (BCL2) expression. In chromatin immunoprecipitation assays, C/EBPβ directly bound to the promoter region of IRF4, BLIMP1, and BCL2. Our data indicate that C/EBPβ is involved in the regulatory network of transcription factors that are critical for plasma cell differentiation and survival. Targeting C/EBPβ may provide a novel therapeutic strategy in the treatment of multiple myeloma. PMID:19717648

  1. p75 neurotrophin receptor and pro-BDNF promote cell survival and migration in clear cell renal cell carcinoma

    Science.gov (United States)

    Sánchez-Prieto, Ricardo; Saada, Sofiane; Naves, Thomas; Guillaudeau, Angélique; Perraud, Aurélie; Sindou, Philippe; Lacroix, Aurélie; Descazeaud, Aurélien; Lalloué, Fabrice; Jauberteau, Marie-Odile

    2016-01-01

    p75NTR, a member of TNF receptor family, is the low affinity receptor common to several mature neurotrophins and the high affinity receptor for pro-neurotrophins. Brain-Derived Neurotrophic Factor (BDNF), a member of neurotrophin family has been described to play an important role in development and progression of several cancers, through its binding to a high affinity tyrosine kinase receptor B (TrkB) and/or p75NTR. However, the functions of these two receptors in renal cell carcinoma (RCC) have never been investigated. An overexpression of p75NTR, pro-BDNF, and to a lesser extent for TrkB and sortilin, was detected by immunohistochemistry in a cohort of 83 clear cell RCC tumors. p75NTR, mainly expressed in tumor tissues, was significantly associated with higher Fuhrman grade in multivariate analysis. In two derived-RCC lines, 786-O and ACHN cells, we demonstrated that pro-BDNF induced cell survival and migration, through p75NTR as provided by p75NTR RNA silencing or blocking anti-p75NTR antibody. This mechanism is independent of TrkB activation as demonstrated by k252a, a tyrosine kinase inhibitor for Trk neurotrophin receptors. Taken together, these data highlight for the first time an important role for p75NTR in renal cancer and indicate a putative novel target therapy in RCC. PMID:27120782

  2. Cell survival in carbon beams - comparison of amorphous track model predictions

    DEFF Research Database (Denmark)

    Grzanka, L.; Greilich, S.; Korcyl, M.

    distribution models, and gamma response models was developed. This software can be used for direct numerical comparison between the models, submodels and their parameters and experimental data. In the present paper, we look at 10%-survival data from cell lines irradiated in vitro with carbon and proton beams......Introduction: Predictions of the radiobiological effectiveness (RBE) play an essential role in treatment planning with heavy charged particles. Amorphous track models ( [1] , [2] , also referred to as track structure models) provide currently the most suitable description of cell survival under ion...... by Tsuruoka et al. [4] . Results and conclusion: Preliminary results show a good agreement of models predictions and the experimental data for clinical doses. When investigating the influence of radial dose distributions on inactivation cross section in the Katz model, we found that one of the most important...

  3. The FGFR/MEK/ERK/brachyury pathway is critical for chordoma cell growth and survival.

    Science.gov (United States)

    Hu, Yunping; Mintz, Akiva; Shah, Sagar R; Quinones-Hinojosa, Alfredo; Hsu, Wesley

    2014-07-01

    Recent evidence suggests that the expression of brachyury is necessary for chordoma growth. However, the mechanism associated with brachyury-regulated cell growth is poorly understood. Fibroblast growth factor (FGF), a regulator of brachyury expression in normal tissue, may also play an important role in chordoma pathophysiology. Using a panel of chordoma cell lines, we explored the role of FGF signaling and brachyury in cell growth and survival. Western blots showed that all chordoma cell lines expressed fibroblast growth factor receptor 2 (FGFR2), FGFR3, mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase (ERK), whereas no cell lines expressed FGFR1 and FGFR4. Results of enzyme-linked immunosorbent assay indicated that chordoma cells produced FGF2. Neutralization of FGF2 inhibited MEK/ERK phosphorylation, decreased brachyury expression and induced apoptosis while reducing cell growth. Activation of the FGFR/MEK/ERK/brachyury pathway by FGF2-initiated phosphorylation of FGFR substrate 2 (FRS2)-α (Tyr196) prevented apoptosis while promoting cell growth and epithelial-mesenchymal transition (EMT). Immunofluorescence staining showed that FGF2 promoted the translocation of phosphorylated ERK to the nucleus and increased brachyury expression. The selective inhibition of FGFR, MEK and ERK phosphorylation by PD173074, PD0325901 and PD184352, respectively, decreased brachyury expression, induced apoptosis, and inhibited cell growth and EMT. Moreover, knockdown of brachyury by small hairpin RNA reduced FGF2 secretion, inhibited FGFR/MEK/ERK phosphorylation and blocked the effects of FGF2 on cell growth, apoptosis and EMT. Those findings highlight that FGFR/MEK/ERK/brachyury pathway coordinately regulates chordoma cell growth and survival and may represent a novel chemotherapeutic target for chordoma.

  4. The cellular state determines the effect of melatonin on the survival of mixed cerebellar cell culture.

    Directory of Open Access Journals (Sweden)

    Daiane Gil Franco

    Full Text Available The constitutive activation of nuclear factor-κB (NF-κB, a key transcription factor involved in neuroinflammation, is essential for the survival of neurons in situ and of cerebellar granule cells in culture. Melatonin is known to inhibit the activation of NF-κB and has a cytoprotective function. In this study, we evaluated whether the cytoprotective effect of melatonin depends on the state of activation of a mixed cerebellar culture that is composed predominantly of granule cells; we tested the effect of melatonin on cultured rat cerebellar cells stimulated or not with lipopolysaccharide (LPS. The addition of melatonin (0.1 nM-1 µM reduced the survival of naïve cells while inhibiting LPS-induced cell death. Melatonin (100 nM transiently (15 min inhibited the nuclear translocation of both NF-κB dimers (p50/p50, p50/RelA and, after 60 min, increased the activation of p50/RelA. Melatonin-induced p50/RelA activity in naïve cells resulted in the transcription of inducible nitric oxide synthase (iNOS and the production of NO. Otherwise, in cultures treated with LPS, melatonin blocked the LPS-induced activation of p50/RelA and the reduction in p50/p50 levels and inhibited iNOS expression and NO synthesis. Therefore, melatonin in vehicle-treated cells induces cell death, while it protects against LPS-induced cytotoxicity. In summary, we confirmed that melatonin is a neuroprotective drug when cerebellar cells are challenged; however, melatonin can also lead to cell death when the normal balance of the NF-κB pathway is disturbed. Our data provide a mechanistic basis for understanding the influence of cell context on the final output response of melatonin.

  5. Estradiol promotes pentose phosphate pathway addiction and cell survival via reactivation of Akt in mTORC1 hyperactive cells.

    Science.gov (United States)

    Sun, Y; Gu, X; Zhang, E; Park, M-A; Pereira, A M; Wang, S; Morrison, T; Li, C; Blenis, J; Gerbaudo, V H; Henske, E P; Yu, J J

    2014-05-15

    Lymphangioleiomyomatosis (LAM) is a female-predominant interstitial lung disease that can lead to respiratory failure. LAM cells typically have inactivating TSC2 mutations, leading to mTORC1 activation. The gender specificity of LAM suggests that estradiol contributes to disease development, yet the underlying pathogenic mechanisms are not completely understood. Using metabolomic profiling, we identified an estradiol-enhanced pentose phosphate pathway signature in Tsc2-deficient cells. Estradiol increased levels of cellular NADPH, decreased levels of reactive oxygen species, and enhanced cell survival under oxidative stress. Mechanistically, estradiol reactivated Akt in TSC2-deficient cells in vitro and in vivo, induced membrane translocation of glucose transporters (GLUT1 or GLUT4), and increased glucose uptake in an Akt-dependent manner. (18)F-FDG-PET imaging demonstrated enhanced glucose uptake in xenograft tumors of Tsc2-deficient cells from estradiol-treated mice. Expression array study identified estradiol-enhanced transcript levels of glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway. Consistent with this, G6PD was abundant in xenograft tumors and lung metastatic lesions of Tsc2-deficient cells from estradiol-treated mice. Molecular depletion of G6PD attenuated estradiol-enhanced survival in vitro, and treatment with 6-aminonicotinamide, a competitive inhibitor of G6PD, reduced lung colonization of Tsc2-deficient cells. Collectively, these data indicate that estradiol promotes glucose metabolism in mTORC1 hyperactive cells through the pentose phosphate pathway via Akt reactivation and G6PD upregulation, thereby enhancing cell survival under oxidative stress. Interestingly, a strong correlation between estrogen exposure and G6PD was also found in breast cancer cells. Targeting the pentose phosphate pathway may have therapeutic benefit for LAM and possibly other hormonally dependent neoplasms.

  6. Rac1 selective activation improves retina ganglion cell survival and regeneration.

    Directory of Open Access Journals (Sweden)

    Erika Lorenzetto

    Full Text Available In adult mammals, after optic nerve injury, retinal ganglion cells (RGCs do not regenerate their axons and most of them die by apoptosis within a few days. Recently, several strategies that activate neuronal intracellular pathways were proposed to prevent such degenerative processes. The rho-related small GTPase Rac1 is part of a complex, still not fully understood, intracellular signaling network, mediating in neurons many effects, including axon growth and cell survival. However, its role in neuronal survival and regeneration in vivo has not yet been properly investigated. To address this point we intravitreally injected selective cell-penetrating Rac1 mutants after optic nerve crush and studied the effect on RGC survival and axonal regeneration. We injected two well-characterized L61 constitutively active Tat-Rac1 fusion protein mutants, in which a second F37A or Y40C mutation confers selectivity in downstream signaling pathways. Results showed that, 15 days after crush, both mutants were able to improve survival and to prevent dendrite degeneration, while the one harboring the F37A mutation also improved axonal regeneration. The treatment with F37A mutant for one month did not improve the axonal elongation respect to 15 days. Furthermore, we found an increase of Pak1 T212 phosphorylation and ERK1/2 expression in RGCs after F37A treatment, whereas ERK1/2 was more activated in glial cells after Y40C administration. Our data suggest that the selective activation of distinct Rac1-dependent pathways could represent a therapeutic strategy to counteract neuronal degenerative processes in the retina.

  7. Controlled oxygen release from pyridone endoperoxides promotes cell survival under anoxic conditions

    OpenAIRE

    Benz, Sebastian; Noetzli, Sarah; Siegel, Jay; Eberli, Daniel; Jessen, Henning Jacob

    2013-01-01

    In tissue engineering, survival of larger constructs remains challenging due to limited supply with oxygen caused by a lack of early vascularization. Controlled release of oxygen from small organic molecules represents a possible strategy to prevent cell death under anoxic conditions. A comprehensive study of methylated pyridone-derived endoperoxides has led to the development of water-soluble molecules that undergo retro Diels-Alder reactions in aqueous environment releasing oxygen in high y...

  8. Prognostic factors for survival in metastatic renal cell carcinoma: update 2008.

    Science.gov (United States)

    Bukowski, Ronald M

    2009-05-15

    A variety of prognostic factor models to predict survival in patients with metastatic renal cell carcinoma have been developed. Diverse populations of patients with variable treatments have been used for these analyses. A variety of clinical, pathologic, and molecular factors have been studied, but current models use predominantly easily obtained clinical factors. These approaches are reviewed, and current approaches to further refine and develop these techniques are reviewed.

  9. Targeting proapoptotic protein BAD inhibits survival and self-renewal of cancer stem cells.

    Science.gov (United States)

    Sastry, K S R; Al-Muftah, M A; Li, Pu; Al-Kowari, M K; Wang, E; Ismail Chouchane, A; Kizhakayil, D; Kulik, G; Marincola, F M; Haoudi, A; Chouchane, L

    2014-12-01

    Emerging evidence suggests that the resistance of cancer stem cells (CSC) to many conventional therapies is one of the major limiting factors of cancer therapy efficacy. Identification of mechanisms responsible for survival and self-renewal of CSC will help design new therapeutic strategies that target and eliminate both differentiated cancer cells and CSC. Here we demonstrated the potential role of proapoptotic protein BAD in the biology of CSC in melanoma, prostate and breast cancers. We enriched CD44(+)/CD24(-) cells (CSC) by tumorosphere formation and purified this population by FACS. Both spheres and CSC exhibited increased potential for proliferation, migration, invasion, sphere formation, anchorage-independent growth, as well as upregulation of several stem cell-associated markers. We showed that the phosphorylation of BAD is essential for the survival of CSC. Conversely, ectopic expression of a phosphorylation-deficient mutant BAD induced apoptosis in CSC. This effect was enhanced by treatment with a BH3-mimetic, ABT-737. Both pharmacological agents that inhibit survival kinases and growth factors that are involved in drug resistance delivered their respective cytotoxic and protective effects by modulating the BAD phosphorylation in CSC. Furthermore, the frequency and self-renewal capacity of CSC was significantly reduced by knocking down the BAD expression. Consistent with our in vitro results, significant phosphorylation of BAD was found in CD44(+) CSC of 83% breast tumor specimens. In addition, we also identified a positive correlation between BAD expression and disease stage in prostate cancer, suggesting a role of BAD in tumor advancement. Our studies unveil the role of BAD in the survival and self-renewal of CSC and propose BAD not only as an attractive target for cancer therapy but also as a marker of tumor progression.

  10. Interleukin-10 modified dendritic cells induce allo-hyporesponsiveness and prolong small intestine allograft survival

    Institute of Scientific and Technical Information of China (English)

    Min Zhu; Ming-Fa Wei; Fang Liu; Hui-Fen Shi; Guo Wang

    2003-01-01

    AIM: To investigate whether TL-10-transduced dendritic cells (DCs) could induce tolerogenicity and prolong allograft survival in rat intestinal transplantation.METHODS: Spleen-derived DCs were prepared and genetically modified by hTL-10 gene. The level of IL-10 expression was quantitated by ELTSA. DC function was assessed by MTT in mixed leukocyte reaction. Allogeneic T-cell apoptosis was examined by flow cytometric analysis. Seven days before heterotopic intestinal transplantation, 2x106 donor-derived IL-10-DC were injected intravenously, then transplantation was performed between SD donor and Wistar recipient.RESULTS: Compared with untransduced DC, IL-10-DC could suppress allogeneic mixed leukocyte reaction (MLR). The inhibitory effect was the most striking with the stimulator/effector (S/F) ratio of 1:10. The inhibition rate was 33.25 %,41.19 % (P<0.01) and 22.92 % with the S/E ratio of 1:1,1:10 and 1:50 respectively. At 48 hours and 72 hours by flow cytometry counting, apoptotic T cells responded to IL-10-DC in MLR were 13.8 % and 30.1%, while untransduced group did not undergo significant apoptosis (P<0.05). IL-10-DC pretreated recipients had a moderate survival prolongation with a mean allograft survival of 19.8 days (P<0.01),compared with 7.3±2.4 days in control group and 8.3±2.9days in untransduced DC group. Rejection occurred in the control group within three days. The difference between untreated DC group and control group was not significant.CONCLUSION: IL-10-DC can induce allogenic T-cell hyporesponsiveness in vitro and apoptosis may be involved in it. IL-10-DC pretreatment can prolong intestinal allograft survival in the recipient.

  11. Survival Motor Neuron Protein Regulates Stem Cell Division, Proliferation, and Differentiation in Drosophila

    OpenAIRE

    Stuart J Grice; Ji-Long Liu

    2011-01-01

    Spinal muscular atrophy is a severe neurogenic disease that is caused by mutations in the human survival motor neuron 1 (SMN1) gene. SMN protein is required for the assembly of small nuclear ribonucleoproteins and a dramatic reduction of the protein leads to cell death. It is currently unknown how the reduction of this ubiquitously essential protein can lead to tissue-specific abnormalities. In addition, it is still not known whether the disease is caused by developmental or degenerative defe...

  12. Low GILT expression is associated with poor patient survival in diffuse large B-cell lymphoma

    Directory of Open Access Journals (Sweden)

    Hannah ePhipps-Yonas

    2013-12-01

    Full Text Available The MHC class II-restricted antigen processing pathway presents antigenic peptides acquired in the endocytic route for the activation of CD4+ T cells. Multiple cancers express MHC class II, which may influence the anti-tumor immune response and patient outcome. Low MHC class II expression is associated with poor survival in diffuse large B-cell lymphoma (DLBCL, the most common form of aggressive non-Hodgkin lymphoma. Therefore, we investigated whether gamma-interferon-inducible lysosomal thiol reductase (GILT, an upstream component of the MHC class II-restricted antigen processing pathway that is not regulated by the transcription factor class II transactivator, may be important in DLBCL biology. GILT reduces protein disulfide bonds in the endocytic compartment, exposing additional epitopes for MHC class II binding and facilitating antigen presentation. In each of four independent gene expression profiling cohorts with a total of 585 DLBCL patients, low GILT expression was significantly associated with poor overall survival. In contrast, low expression of a classical MHC class II gene, HLA-DRA, was associated with poor survival in one of four cohorts. The association of low GILT expression with poor survival was independent of established clinical and molecular prognostic factors, the International Prognostic Index and the cell of origin classification, respectively. Immunohistochemical analysis of GILT expression in 96 DLBCL cases demonstrated variation in GILT protein expression within tumor cells which correlated strongly with GILT mRNA expression. These studies identify a novel association between GILT expression and clinical outcome in lymphoma. Our findings underscore the role of antigen processing in DLBCL and suggest that molecules targeting this pathway warrant investigation as potential therapeutics.

  13. Antifreeze protein modulates cell survival during cryopreservation: mediation through influence on ice crystal growth.

    OpenAIRE

    Carpenter, J F; Hansen, T N

    1992-01-01

    Antifreeze proteins (AFPs) are extremely efficient at inhibiting ice recrystallization in frozen solutions. Knight and Duman [Knight, C. A. & Duman, J. G. (1986) Cryobiology 23, 256-263] have proposed that this may be an important function of the proteins in freeze-tolerant organisms. We have tested this proposal in vitro by characterizing the influence of AFP on the recovery of cryopreserved cells, which often can survive cooling and yet subsequently be damaged by ice crystal growth during w...

  14. Kv3.4 potassium channel-mediated electrosignaling controls cell cycle and survival of irradiated leukemia cells.

    Science.gov (United States)

    Palme, Daniela; Misovic, Milan; Schmid, Evi; Klumpp, Dominik; Salih, Helmut R; Rudner, Justine; Huber, Stephan M

    2013-08-01

    Aberrant ion channel expression in the plasma membrane is characteristic for many tumor entities and has been attributed to neoplastic transformation, tumor progression, metastasis, and therapy resistance. The present study aimed to define the function of these "oncogenic" channels for radioresistance of leukemia cells. Chronic myeloid leukemia cells were irradiated (0-6 Gy X ray), ion channel expression and activity, Ca(2+)- and protein signaling, cell cycle progression, and cell survival were assessed by quantitative reverse transcriptase-polymerase chain reaction, patch-clamp recording, fura-2 Ca(2+)-imaging, immunoblotting, flow cytometry, and clonogenic survival assays, respectively. Ionizing radiation-induced G2/M arrest was preceded by activation of Kv3.4-like voltage-gated potassium channels. Channel activation in turn resulted in enhanced Ca(2+) entry and subsequent activation of Ca(2+)/calmodulin-dependent kinase-II, and inactivation of the phosphatase cdc25B and the cyclin-dependent kinase cdc2. Accordingly, channel inhibition by tetraethylammonium and blood-depressing substance-1 and substance-2 or downregulation by RNA interference led to release from radiation-induced G2/M arrest, increased apoptosis, and decreased clonogenic survival. Together, these findings indicate the functional significance of voltage-gated K(+) channels for the radioresistance of myeloid leukemia cells.

  15. Parotid small cell carcinoma presenting with long-term survival after surgery alone: a case report

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    Kanazawa Takeharu

    2012-12-01

    Full Text Available Abstract Introduction Primary involvement of the salivary glands in small cell carcinoma is rare, and has one of the worst prognoses of salivary gland neoplasms. However, it has been reported that some cases have a favorable outcome, although the prognostic factors are still under consideration. Multidisciplinary therapy was usually required to achieve long-term survival. Recently, a resemblance of some small cell carcinomas of the salivary gland to cutaneous Merkel cell carcinoma was suggested; the latter have the potential for spontaneous regression, which is related to a favorable clinical outcome. Case presentation We present a locoregional advanced parotid small cell carcinoma with multiple lymph node metastases in an 87-year-old Asian woman. The tumor was controlled by surgery alone, and nine-year disease-free survival was achieved without any adjunctive therapy. To the best of our knowledge, this is the longest reported follow-up of head and neck small cell carcinoma. Conclusion We believe this to be the first case of small cell carcinoma with involvement of the salivary glands reported in the literature with a good outcome after surgery alone without any adjunctive therapy.

  16. Preoperative Erythrocyte Sedimentation Rate Independently Predicts Overall Survival in Localized Renal Cell Carcinoma following Radical Nephrectomy

    Directory of Open Access Journals (Sweden)

    Brian W. Cross

    2012-01-01

    Full Text Available Objectives. To determine the relationship between preoperative erythrocyte sedimentation rate (ESR and overall survival in localized renal cell carcinoma (RCC following nephrectomy. Methods. 167 patients undergoing nephrectomy for localized RCC had ESR levels measured preoperatively. Receiver Operating Characteristics curves were used to determine Area Under the Curve and relative sensitivity and specificity of preoperative ESR in predicting overall survival. Cut-offs for low (0.0–20.0 mm/hr, intermediate (20.1–50.0 mm/hr, and high risk (>50.0 mm/hr groups were created. Kaplan-Meier analysis was conducted to assess the univariate impact of these ESR-based groups on overall survival. Univariate and multivariate Cox regression analysis was conducted to assess the potential of these groups to predict overall survival, adjusting for other patient and tumor characteristics. Results. Overall, 55.2% were low risk, while 27.0% and 17.8% were intermediate and high risk, respectively. Median (95% CI survival was 44.1 (42.6–45.5 months, 35.5 (32.3–38.8 months, and 32.1 (25.5–38.6 months, respectively. After controlling for other patient and tumor characteristics, intermediate and high risk groups experienced a 4.5-fold (HR: 4.509, 95% CI: 0.735–27.649 and 18.5-fold (HR: 18.531, 95% CI: 2.117–162.228 increased risk of overall mortality, respectively. Conclusion. Preoperative ESR values represent a robust predictor of overall survival following nephrectomy in localized RCC.

  17. Hypercoagulability as a prognostic factor for survival in patients with metastatic renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Somonova Oksana V

    2009-03-01

    Full Text Available Abstract Background In experimental systems, interference with coagulation can affect tumor biology. We suggested that abnormal coagulation could be a negative predictor for response to immunotherapy and survival among patients with metastatic renal cell carcinoma (MRCC. Methods To address this issue, retrospective analysis of 289 previously untreated MRCC patients entering on institutional review board-approved clinical trials was conducted between 2003 and 2006. In addition, two groups of MRCC patients with (n = 28 or without (n = 28 hypercoagulability were compared in a case-control study. Baseline and treatment characteristics were well balanced. Results Hypercoagulability was present at treatment start in 40% of patients. Median baseline fibrinogen was 6.2 mg/dl. Serious disorders were found in 68% of patients. Abnormal coagulation was strongly associated with a number of metastatic sites (2 and more metastatic sites vs. 0–1 (P = .001. Patients with high extent of hypercoagulability had significantly higher number of metastatic sites (P = .02. On univariate analysis, patients with hypercoagulability had significantly shorter overall survival than patients with normal coagulation; median survivals of 8.9 and 16.3, respectively (P = .001. Short survival and low response rate also were significantly associated with hypercoagulability in a case-control study. Median survival was 8.2 months and 14.6 months, respectively (P = .0011. Disease control rate (overall response + stable disease was significantly higher in patients with normal coagulation: 71.4 versus 42.9% (P = .003. Conclusion Hypercoagulability disorders were found to be prognostic factor for response rate to systemic therapy and survival in patients with MRCC.

  18. Survival Outcome of Squamous Cell Carcinoma Arising from Sinonasal Inverted Papilloma

    Institute of Scientific and Technical Information of China (English)

    Qing-Zhuang Liang; De-Zhi Li; Xiao-Lei Wang; Hui Huang; Zhen-Gang Xu; Yue-Huang Wu

    2015-01-01

    Background:Sinonasal inverted papilloma (IP) is a rare benign tumor of the nasal cavities and paranasal sinuses.It is destructive or bone-remodeling,tends to recur after surgical resection,and has a significant malignant potential.The present study aimed to perform a retrospective analysis of patients with squamous cell carcinoma (SCC) arising from IP,including characteristics,survival outcome,and predictors of associated malignancy.Methods:The medical records of 213 patients diagnosed with IP from January 1970 to January 2014 were retrospectively reviewed.Eighty-seven patients were diagnosed with SCC/IP; their clinical characteristics,treatments,and survival outcomes were analyzed.Results:Of the 87 patients with SCC/IP,the 5-and 10-year overall survival outcomes were 39.6% and 31.8%,respectively.Twenty-nine of these patients received surgery and 58 received combined surgery and radiation.Of the patients with stages Ⅲ-Ⅳ,the 5-year survival rate was 30.7% for those treated with surgery only and 39.9% for those given the combination treatment (P =0.849).Factors associated with significantly poor prognosis were advanced-stage,metachronous tumors,or with cranial base and orbit invasion.Age,synchronous or metachronous tumors,and pathological stage were independent risk factors for mortality,shown by multivariate analysis.Conclusion:Patients with SCC/IP had low overall survival outcomes.Advanced age,stage,and metachronous tumors are the main factors affecting prognosis.Treatment planning should consider high-risk factors to improve survival outcome.

  19. REDD1 Is Essential for Optimal T Cell Proliferation and Survival.

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    Emma L Reuschel

    Full Text Available REDD1 is a highly conserved stress response protein that is upregulated following many types of cellular stress, including hypoxia, DNA damage, energy stress, ER stress, and nutrient deprivation. Recently, REDD1 was shown to be involved in dexamethasone induced autophagy in murine thymocytes. However, we know little of REDD1's function in mature T cells. Here we show for the first time that REDD1 is upregulated following T cell stimulation with PHA or CD3/CD28 beads. REDD1 knockout T cells exhibit a defect in proliferation and cell survival, although markers of activation appear normal. These findings demonstrate a previously unappreciated role for REDD1 in T cell function.

  20. Intracellular trehalose improves the survival of human red blood cells by freeze-drying

    Institute of Scientific and Technical Information of China (English)

    HE Hui; LIU Baolin; HUA Zezhao; LI Chuan; WU Zhengzheng

    2007-01-01

    Freeze-drying of human red blood cells has a potential important application for blood transfusion.The aim of this study was to investigate the effects ofintracellular trehalose on the survival of red blood cells after freeze-drying and rehydration.Fresh red blood cells were incubated in trehalose solutions of various concentrations at 37℃ for 7 h following freeze-drying.Polyvinylpyrrolidone,Trehalose,sodium citrate,and human serum albumin were used as extracellular protective agents for the freeze-drying of red blood cells.The results indicated that the intracellular trehalose concentration was increased with increasing concentration of extracellular trehalose solution,and the maximum concen tration of intracellular trehalose reached 35 mmol/L.The viability of freeze-dried red blood cells increased with the increment of intracellular trehalose concentration.

  1. YAP enhances autophagic flux to promote breast cancer cell survival in response to nutrient deprivation.

    Directory of Open Access Journals (Sweden)

    Qinghe Song

    Full Text Available The Yes-associated protein (YAP, a transcriptional coactivator inactivated by the Hippo tumor suppressor pathway, functions as an oncoprotein in a variety of cancers. However, its contribution to breast cancer remains controversial. This study investigated the role of YAP in breast cancer cells under nutrient deprivation (ND. Here, we show that YAP knockdown sensitized MCF7 breast cancer cells to nutrient deprivation-induced apoptosis. Furthermore, in response to ND, YAP increased the autolysosome degradation, thereby enhancing the cellular autophagic flux in breast cancer cells. Of note, autophagy is crucial for YAP to protect MCF7 cells from apoptosis under ND conditions. In addition, the TEA domain (TEAD family of growth-promoting transcription factors was indispensable for YAP-mediated regulation of autophagy. Collectively, our data reveal a role for YAP in promoting breast cancer cell survival upon ND stress and uncover an unappreciated function of YAP/TEAD in the regulation of autophagy.

  2. Model of Protein Kinase B for Cell Survival/Death and its Equivalent Bio Circuit

    Science.gov (United States)

    Jain, Shruti; Naik, Pradeep K.; Bhooshan, Sunil V.

    2011-12-01

    Signaling pathways have traditionally focused on delineating immediate upstream and down stream interactions, and then organizing these interactions into linear cascades that relay and regulate information from cell surface receptors to cellular effectors such as metabolic enzymes, channels or transcription factors. However, recent analyses of signaling pathways have revealed that cellular signals do not necessarily propagate in a linear fashion. Because of their size and complexity, these networks are often too complicated for the human mind to organize and analyze. AkT (protein kinase B) is a central signaling molecule in the phosphatidylinositol 3-kinase pathway that is frequently activated in human cancer. Here we provide an overview of recent findings, how AkT promotes cell survival by inhibiting apoptosis by phosphorylating and inactivating several targets, including forkhead transcription factors, and caspase-9. The ability of AkT to promote survival was dependent on and proportional to its kinase activity. We have made computational model for AkT, on the basis of that model we have made the truth tables, Boolean equations and than implement the equations using logic circuits and Bio-circuits showing cell survival and death.

  3. Impact of Pancreatic Rat Islet Density on Cell Survival during Hypoxia

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    A. Rodriguez-Brotons

    2016-01-01

    Full Text Available In bioartificial pancreases (BP, the number of islets needed to restore normoglycaemia in the diabetic patient is critical. However, the confinement of a high quantity of islets in a limited space may impact islet survival, particularly in regard to the low oxygen partial pressure (PO2 in such environments. The aim of the present study was to evaluate the impact of islet number in a confined space under hypoxia on cell survival. Rat islets were seeded at three different concentrations (150, 300, and 600 Islet Equivalents (IEQ/cm2 and cultured in normal atmospheric pressure (160 mmHg as well as hypoxic conditions (15 mmHg for 24 hours. Cell viability, function, hypoxia-induced changes in gene expression, and cytokine secretion were then assessed. Notably, hypoxia appeared to induce a decrease in viability and increasing islet density exacerbated the observed increase in cellular apoptosis as well as the loss of function. These changes were also associated with an increase in inflammatory gene transcription. Taken together, these data indicate that when a high number of islets are confined to a small space under hypoxia, cell viability and function are significantly impacted. Thus, in order to improve islet survival in this environment during transplantation, oxygenation is of critical importance.

  4. Genetic variants in ABCG1 are associated with survival of nonsmall-cell lung cancer patients.

    Science.gov (United States)

    Wang, Yanru; Liu, Hongliang; Ready, Neal E; Su, Li; Wei, Yongyue; Christiani, David C; Wei, Qingyi

    2016-06-01

    Cell membrane transporters and metabolic enzymes play a crucial role in the transportation of a wide variety of substrates that maintain homeostasis in biological processes. We explored associations between genetic variants in these genes and survival of nonsmall-cell lung cancer (NSCLC) patients by reanalyzing two datasets from published genome-wide association studies (GWASs). In the discovery by using the GWAS dataset of the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial, we evaluated associations of 1,245 single-nucleotide polymorphisms (SNPs) in genes of four transporter families and two metabolic enzyme families with survival of 1,185 NSCLC patients. We then performed a replication analysis in the Harvard University Lung Cancer study (LCS) with 984 NSCLC patients. Multivariate Cox proportional hazards regression and false discovery rate (FDR) corrections were performed to evaluate the associations. We identified that 21 genotyped SNPs in eight gene regions were significantly associated with survival with FDR ≤ 0.1 in the discovery dataset. Subsequently, we confirmed six SNPs, which were putative functional, in ABCG1 of the ATP-binding cassette transporter family in the replication dataset. In the pooled analysis, two tagging (at r(2)  > 0.8 for linkage disequilibrium with other replicated SNPs)/functional SNPs were independently associated with survival: rs225388 G > A [adjusted hazards ratio (HR) = 1.12, 95% confidence interval (CI) = 1.03-1.20, Ptrend  = 4.6 × 10(-3)] and rs225390 A > G (adjusted HR = 1.16, 95% CI = 1.07-1.25, Ptrend  = 3.8 × 10(-4) ). Our results indicated that genetic variants of ABCG1 may be predictors of survival of NSCLC patients.

  5. Sunitinib-induced hypothyroidism predicts progression-free survival in metastatic renal cell carcinoma patients.

    Science.gov (United States)

    Buda-Nowak, Anna; Kucharz, Jakub; Dumnicka, Paulina; Kuzniewski, Marek; Herman, Roman Maria; Zygulska, Aneta L; Kusnierz-Cabala, Beata

    2017-04-01

    Sunitinib is a tyrosine kinase inhibitor (TKI) used in treatment of metastatic renal cell carcinoma (mRCC), gastrointestinal stromal tumors and pancreatic neuroendocrine tumors. One of the most common side effects related to sunitinib is hypothyroidism. Recent trials suggest correlation between the incidence of hypothyroidism and treatment outcome in patients treated with TKI. This study evaluates whether development of hypothyroidism is a predictive marker of progression-free survival (PFS) in patients with mRCC treated with sunitinib. Twenty-seven patients diagnosed with clear cell mRCC, after nephrectomy and in 'good' or 'intermediate' MSKCC risk prognostic group, were included in the study. All patients received sunitinib as a first-line treatment on a standard schedule (initial dose 50 mg/day, 4 weeks on, 2 weeks off). The thyroid-stimulating hormone serum levels were obtained at the baseline and every 12 weeks of treatment. In statistic analyses, we used Kaplan-Meier method for assessment of progression-free survival; for comparison of survival, we used log-rank test. In our study, the incidence of hypothyroidism was 44%. The patients who had developed hypothyroidism had better median PFS to patients with normal thyroid function 28,3 months [95% (CI) 20.4-36.2 months] versus 9.8 months (6.4-13.1 months). In survival analysis, we perceive that thyroid dysfunction is a predictive factor of a progression-free survival (PFS). In the unified group of patients, the development of hypothyroidism during treatment with sunitinib is a positive marker for PFS. During that treatment, thyroid function should be evaluated regularly.

  6. Activation of Melatonin Signaling Promotes β-Cell Survival and Function.

    Science.gov (United States)

    Costes, Safia; Boss, Marti; Thomas, Anthony P; Matveyenko, Aleksey V

    2015-05-01

    Type 2 diabetes mellitus (T2DM) is characterized by pancreatic islet failure due to loss of β-cell secretory function and mass. Studies have identified a link between a variance in the gene encoding melatonin (MT) receptor 2, T2DM, and impaired insulin secretion. This genetic linkage raises the question whether MT signaling plays a role in regulation of β-cell function and survival in T2DM. To address this postulate, we used INS 832/13 cells to test whether activation of MT signaling attenuates proteotoxicity-induced β-cell apoptosis and through which molecular mechanism. We also used nondiabetic and T2DM human islets to test the potential of MT signaling to attenuate deleterious effects of glucotoxicity and T2DM on β-cell function. MT signaling in β-cells (with duration designed to mimic typical nightly exposure) significantly enhanced activation of the cAMP-dependent signal transduction pathway and attenuated proteotoxicity-induced β-cell apoptosis evidenced by reduced caspase-3 cleavage (∼40%), decreased activation of stress-activated protein kinase/Jun-amino-terminal kinase (∼50%) and diminished oxidative stress response. Activation of MT signaling in human islets was shown to restore glucose-stimulated insulin secretion in islets exposed to chronic hyperglycemia as well as in T2DM islets. Our data suggest that β-cell MT signaling is important for the regulation of β-cell survival and function and implies a preventative and therapeutic potential for preservation of β-cell mass and function in T2DM.

  7. Melanin dependent survival of Apergillus fumigatus conidia in lung epithelial cells.

    Science.gov (United States)

    Amin, Shayista; Thywissen, Andreas; Heinekamp, Thorsten; Saluz, Hans Peter; Brakhage, Axel A

    2014-07-01

    Aspergillus fumigatus is the most important air-borne pathogenic fungus of humans. Upon inhalation of conidia, the fungus makes close contact with lung epithelial cells, which only possess low phagocytic activity. These cells are in particular interesting to address the question whether there is some form of persistence of conidia of A. fumigatus in the human host. Therefore, by also using uracil-auxotrophic mutant strains, we were able to investigate the interaction of A549 lung epithelial cells and A. fumigatus conidia in detail for long periods. Interestingly, unlike professional phagocytes, our study showed that the presence of conidial dihydroxynaphthalene (DHN) melanin enhanced the uptake of A. fumigatus conidia by epithelial cells when compared with non-pigmented pksP mutant conidia. Furthermore, conidia of A. fumigatus were able to survive within epithelial cells. This was due to the presence of DHN melanin in the cell wall of conidia, because melanised wild-type conidia showed a higher survival rate inside epithelial cells and led to inhibition of acidification of phagolysosomes. Both effects were not observed for white (non-melanised) conidia of the pksP mutant strain. Moreover, in contrast to pksP mutant conidia, melanised wild-type conidia were able to inhibit the extrinsic apoptotic pathway in A549 lung epithelial cells even for longer periods. The anti-apoptotic effect was not restricted to conidia, because both conidia-derived melanin ghosts (cell-free DHN melanin) and a different type of melanin, dihydroxyphenylalanine (DOPA) melanin, acted anti-apoptotically. Taken together, these data indicate the possibility of melanin-dependent persistence of conidia in lung epithelial cells.

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

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    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.

  9. Improved Survival with T Cell Clonotype Stability After Anti–CTLA-4 Treatment in Cancer Patients

    Science.gov (United States)

    Cha, Edward; Klinger, Mark; Hou, Yafei; Cummings, Craig; Ribas, Antoni; Faham, Malek; Fong, Lawrence

    2015-01-01

    Cytotoxic T lymphocyte–associated antigen-4 (CTLA-4) blockade can promote antitumor T cell immunity and clinical responses. The mechanism by which anti–CTLA-4 antibodies induces antitumor responses is controversial. To determine the effects of CTLA-4 blockade on the T cell repertoire, we used next-generation deep sequencing to measure the frequency of individual rearranged T cell receptor β (TCRβ) genes, thereby characterizing the diversity of rearrangements, known as T cell clonotypes. CTLA-4 blockade in patients with metastatic castration-resistant prostate cancer and metastatic melanoma resulted in both expansion and loss of T cell clonotypes, consistent with a global turnover of the T cell repertoire. Overall, this treatment increased TCR diversity as reflected in the number of unique TCR clonotypes. The repertoire of clonotypes continued to evolve over subsequent months of treatment. Whereas the number of clonotypes that increased with treatment was not associated with clinical outcome, improved overall survival was associated with maintenance of high-frequency clones at baseline. In contrast, the highest-frequency clonotypes fell with treatment in patients with short overall survival. Stably maintained clonotypes included T cells having high-avidity TCR such as virus-reactive T cells. Together, these results suggest that CTLA-4 blockade induces T cell repertoire evolution and diversification. Moreover, improved clinical outcomes are associated with less clonotype loss, consistent with the maintenance of high-frequency TCR clonotypes during treatment. These clones may represent the presence of preexisting high-avidity T cells that may be relevant in the antitumor response. PMID:24871131

  10. Signal transducer and activator of transcription 3 is involved in cell growth and survival of human rhabdomyosarcoma and osteosarcoma cells

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    Qualman Stephen J

    2007-06-01

    Full Text Available Abstract Background Stat3 has been classified as a proto-oncogene and constitutive Stat3 signaling appears to be involved in oncogenesis of human cancers. However, whether constitutive Stat3 signaling plays a role in the survival and growth of osteosarcomas, rhabdomyosarcomas, and soft-tissue sarcomas is still unclear. Methods To examine whether Stat3 is activated in osteosarcomas, rhabdomyosarcomas and other soft-tissue sarcomas we analyzed sarcoma tissue microarray slides and sarcoma cell lines using immunohistochemistry and Western blot analysis, respectively, with a phospho-specific Stat3 antibody. To examine whether the activated Stat3 pathway is important for sarcoma cell growth and survival, adenovirus-mediated expression of a dominant-negative Stat3 (Y705F and a small molecule inhibitor (termed STA-21 were used to inhibit constitutive Stat3 signaling in human sarcoma cell lines expressing elevated levels of Stat3 phosphorylation. Cell viability was determined by MTT assays and induction of apoptosis was analyzed by western blotting using antibodies that specifically recognize cleaved caspases-3, 8, and 9. Results Stat3 phosphorylation is elevated in 19% (21/113 of osteosarcoma, 27% (17/64 of rhabdomyosarcoma, and 15% (22/151 of other soft-tissue sarcoma tissues as well as in sarcoma cell lines. Expression of the dominant-negative Stat3 and treatment of STA-21 inhibited cell viability and growth and induced apoptosis through caspases 3, 8 and 9 pathways in human sarcoma cell lines expressing elevated levels of phosphorylated Stat3. Conclusion This study demonstrates that Stat3 phosphorylation is elevated in human rhabdomyosarcoma, osteosarcomas and soft-tissue sarcomas. Furthermore, the activated Stat3 pathway is important for cell growth and survival of human sarcoma cells.

  11. Nitric oxide mediates the survival action of IGF-1 and insulin in pancreatic beta cells.

    Science.gov (United States)

    Cahuana, Gladys M; Tejedo, Juan R; Hmadcha, Abdelkrim; Ramírez, Remedios; Cuesta, Antonio L; Soria, Bernat; Martin, Franz; Bedoya, Francisco J

    2008-02-01

    Generation of low levels of nitric oxide (NO) contributes to beta cell survival in vitro. The purpose of this study was to explore the link between NO and the survival pathway triggered by insulin-like growth factor-1 (IGF-1) and insulin in insulin producing RINm5F cells and in pancreatic islets. Results show that exposure of cells to IGF-1/insulin protects against serum deprivation-induced apoptosis. This action is prevented with inhibitors of NO generation, PI3K and Akt. Moreover, transfection with the negative dominant form of the tyrosine kinase c-Src abrogates the effect of IGF-1 and insulin on DNA fragmentation. An increase in the expression level of NOS3 protein and in the enzyme activity is observed following exposure of serum-deprived RINm5F cells to IGF-1 and insulin. Phosphorylation of IRS-1, IRS-2 and to less extent IRS-3 takes place when serum-deprived RINm5F cells and rat pancreatic islets are exposed to either IGF-1, insulin, or diethylenetriamine nitric oxide adduct (DETA/NO). In human islets, IRS-1 and IRS-2 proteins are present and tyrosine phosphorylated upon exposure to IGF-1, insulin and DETA/NO. Both rat and human pancreatic islets undergo DNA fragmentation when cultured in serum-free medium and IGF-1, insulin and DETA/NO protect efficiently from this damage. We then conclude that generation of NO participates in the activation of survival pathways by IGF-1 and insulin in beta cells.

  12. Human hepatocyte growth factor (hHGF-modified hepatic oval cells improve liver transplant survival.

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    Zhu Li

    Full Text Available Despite progress in the field of immunosuppression, acute rejection is still a common postoperative complication following liver transplantation. This study aims to investigate the capacity of the human hepatocyte growth factor (hHGF in modifying hepatic oval cells (HOCs administered simultaneously with orthotopic liver transplantation as a means of improving graft survival. HOCs were activated and isolated using a modified 2-acetylaminofluorene/partial hepatectomy (2-AAF/PH model in male Lewis rats. A HOC line stably expressing the HGF gene was established following stable transfection of the pBLAST2-hHGF plasmid. Our results demonstrated that hHGF-modified HOCs could efficiently differentiate into hepatocytes and bile duct epithelial cells in vitro. Administration of HOCs at the time of liver transplantation induced a wider distribution of SRY-positive donor cells in liver tissues. Administration of hHGF-HOC at the time of transplantation remarkably prolonged the median survival time and improved liver function for recipients compared to these parameters in the other treatment groups (P<0.05. Moreover, hHGF-HOC administration at the time of liver transplantation significantly suppressed elevation of interleukin-2 (IL-2, tumor necrosis factor-α (TNF-α and interferon-γ (IFN-γ levels while increasing the production of IL-10 and TGF-β1 (P<0.05. HOC or hHGF-HOC administration promoted cell proliferation, reduced cell apoptosis, and decreased liver allograft rejection rates. Furthermore, hHGF-modified HOCs more efficiently reduced acute allograft rejection (P<0.05 versus HOC transplantation only. Our results indicate that the combination of hHGF-modified HOCs with liver transplantation decreased host anti-graft immune responses resulting in a reduction of allograft rejection rates and prolonging graft survival in recipient rats. This suggests that HOC-based cell transplantation therapies can be developed as a means of treating severe liver

  13. SNHG5 promotes colorectal cancer cell survival by counteracting STAU1-mediated mRNA destabilization

    DEFF Research Database (Denmark)

    Damas, Nkerorema Djodji; Marcatti, Michela; Côme, Christophe;

    2016-01-01

    We currently have limited knowledge of the involvement of long non-coding RNAs (lncRNAs) in normal cellular processes and pathologies. Here, we identify and characterize SNHG5 as a stable cytoplasmic lncRNA with up-regulated expression in colorectal cancer. Depletion of SNHG5 induces cell cycle...... characterize SNHG5 as a lncRNA promoting tumour cell survival in colorectal cancer and delineate a novel mechanism in which a cytoplasmic lncRNA functions through blocking the action of STAU1....

  14. Different Effects of BORIS/CTCFL on Stemness Gene Expression, Sphere Formation and Cell Survival in Epithelial Cancer Stem Cells.

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    Loredana Alberti

    Full Text Available Cancer stem cells are cancer cells characterized by stem cell properties and represent a small population of tumor cells that drives tumor development, progression, metastasis and drug resistance. To date, the molecular mechanisms that generate and regulate cancer stem cells are not well defined. BORIS (Brother of Regulator of Imprinted Sites or CTCFL (CTCF-like is a DNA-binding protein that is expressed in normal tissues only in germ cells and is re-activated in tumors. Recent evidences have highlighted the correlation of BORIS/CTCFL expression with poor overall survival of different cancer patients. We have previously shown an association of BORIS-expressing cells with stemness gene expression in embryonic cancer cells. Here, we studied the role of BORIS in epithelial tumor cells. Using BORIS-molecular beacon that was already validated, we were able to show the presence of BORIS mRNA in cancer stem cell-enriched populations (side population and spheres of cervical, colon and breast tumor cells. BORIS silencing studies showed a decrease of sphere formation capacity in breast and colon tumor cells. Importantly, BORIS-silencing led to down-regulation of hTERT, stem cell (NANOG, OCT4, SOX2 and BMI1 and cancer stem cell markers (ABCG2, CD44 and ALDH1 genes. Conversely, BORIS-induction led to up-regulation of the same genes. These phenotypes were observed in cervical, colon and invasive breast tumor cells. However, a completely different behavior was observed in the non-invasive breast tumor cells (MCF7. Indeed, these cells acquired an epithelial mesenchymal transition phenotype after BORIS silencing. Our results demonstrate that BORIS is associated with cancer stem cell-enriched populations of several epithelial tumor cells and the different phenotypes depend on the origin of tumor cells.

  15. Survival after Pneumonectomy for Stage III Non-small Cell Lung Cancer

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    Sibu P. Saha

    2014-01-01

    Full Text Available Objectives: Stage III non-small cell lung cancer (NSCLC has a poor prognosis. Reports suggest that five-year survival after current treatment is between 14 to 24 percent. The purpose of this retrospective study was to investigate the morbidity and mortality of patients diagnosed with stage III NSCLC and treated with pneumonectomy at the University of Kentucky Medical Center in Lexington, KY. Methods: We reviewed the medical record and tumor registry follow-up data on 100 consecutive patients who underwent pneumonectomy for lung cancer at the University of Kentucky. Results: We identified thirty-six patients in stage III who underwent pneumonectomy. Ten patients had surgery only, eight patients received adjuvant chemotherapy, and eighteen patients received neoadjuvant therapy. There was one surgical death in this series. Mean follow-up was 2.9 years. One-, three-, and five-year survival was 66%, 38%, and 38%, respectively. Five-year survival for the group with adjuvant therapy was 60%. Conclusion: Most lung cancer patients present with advanced disease and the prognosis remains poor. Our experience indicates resection offers an above average chance of long-term survival when supplemented with neoadjuvant and/or adjuvant therapy.

  16. VILIP-1 downregulation in non-small cell lung carcinomas: mechanisms and prediction of survival.

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    Jian Fu

    Full Text Available VILIP-1, a member of the neuronal Ca++ sensor protein family, acts as a tumor suppressor gene in an experimental animal model by inhibiting cell proliferation, adhesion and invasiveness of squamous cell carcinoma cells. Western Blot analysis of human tumor cells showed that VILIP-1 expression was undetectable in several types of human tumor cells, including 11 out of 12 non-small cell lung carcinoma (NSCLC cell lines. The down-regulation of VILIP-1 was due to loss of VILIP-1 mRNA transcripts. Rearrangements, large gene deletions or mutations were not found. Hypermethylation of the VILIP-1 promoter played an important role in gene silencing. In most VILIP-1-silent cells the VILIP-1 promoter was methylated. In vitro methylation of the VILIP-1 promoter reduced its activity in a promoter-reporter assay. Transcriptional activity of endogenous VILIP-1 promoter was recovered by treatment with 5'-aza-2'-deoxycytidine (5'-Aza-dC. Trichostatin A (TSA, a histone deacetylase inhibitor, potently induced VILIP-1 expression, indicating that histone deacetylation is an additional mechanism of VILIP-1 silencing. TSA increased histone H3 and H4 acetylation in the region of the VILIP-1 promoter. Furthermore, statistical analysis of expression and promoter methylation (n = 150 primary NSCLC samples showed a significant relationship between promoter methylation and protein expression downregulation as well as between survival and decreased or absent VILIP-1 expression in lung cancer tissues (p<0.0001. VILIP-1 expression is silenced by promoter hypermethylation and histone deacetylation in aggressive NSCLC cell lines and primary tumors and its clinical evaluation could have a role as a predictor of short-term survival in lung cancer patients.

  17. The pro-adhesive and pro-survival effects of glucocorticoid in human ovarian cancer cells.

    Science.gov (United States)

    Yin, Lijuan; Fang, Fang; Song, Xinglei; Wang, Yan; Huang, Gaoxiang; Su, Jie; Hui, Ning; Lu, Jian

    2016-07-01

    Cell adhesion to extracellular matrix (ECM) is controlled by multiple signaling molecules and intracellular pathways, and is pivotal for survival and growth of cells from most solid tumors. Our previous works demonstrated that dexamethasone (DEX) significantly enhances cell adhesion and cell resistance to chemotherapeutics by increasing the levels of integrin β1, α4, and α5 in human ovarian cancer cells. However, it is unclear whether the components of ECM or other membrane molecules are also involved in the pro-adhesive effect of DEX in ovarian cancer cells. In this study, we demonstrated that the treatment of cells with DEX did not change the expression of collagens (I, III, and IV), laminin, CD44, and its principal ligand hyaluronan (HA), but significantly increased the levels of intracellular and secreted fibronectin (FN). Inhibiting the expression of FN with FN1 siRNA or blocking CD44, another FN receptor, with CD44 blocking antibody significantly attenuated the pro-adhesion of DEX, indicating that upregulation of FN mediates the pro-adhesive effect of DEX by its interaction with CD44 besides integrin β1. Moreover, DEX significantly enhanced cell resistance to the chemotherapeutic agent paclitaxel (PTX) by activating PI-3K-Akt pathway. Finally, we found that DEX also significantly upregulated the expression of MUC1, a transmembrane glycoprotein. Inhibiting the expression of MUC1 with MUC1 siRNA significantly attenuated the DEX-induced effects of pro-adhesion, Akt-activation, and pro-survival. In conclusion, these results provide new data that upregulation of FN and MUC1 by DEX contributes to DEX-induced pro-adhesion and protects ovarian cancer cells from chemotherapy.

  18. Hedgehog pathway regulators influence cervical cancer cell proliferation, survival and migration

    Energy Technology Data Exchange (ETDEWEB)

    Samarzija, Ivana [Ecole Polytechnique Federale Lausanne (EPFL), Department of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), 1015 Lausanne (Switzerland); Beard, Peter, E-mail: peter.beard@epfl.ch [Ecole Polytechnique Federale Lausanne (EPFL), Department of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), 1015 Lausanne (Switzerland)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer Unknown cellular mutations complement papillomavirus-induced carcinogenesis. Black-Right-Pointing-Pointer Hedgehog pathway components are expressed by cervical cancer cells. Black-Right-Pointing-Pointer Hedgehog pathway activators and inhibitors regulate cervical cancer cell biology. Black-Right-Pointing-Pointer Cell immortalization by papillomavirus and activation of Hedgehog are independent. -- Abstract: Human papillomavirus (HPV) infection is considered to be a primary hit that causes cervical cancer. However, infection with this agent, although needed, is not sufficient for a cancer to develop. Additional cellular changes are required to complement the action of HPV, but the precise nature of these changes is not clear. Here, we studied the function of the Hedgehog (Hh) signaling pathway in cervical cancer. The Hh pathway can have a role in a number of cancers, including those of liver, lung and digestive tract. We found that components of the Hh pathway are expressed in several cervical cancer cell lines, indicating that there could exists an autocrine Hh signaling loop in these cells. Inhibition of Hh signaling reduces proliferation and survival of the cervical cancer cells and induces their apoptosis as seen by the up-regulation of the pro-apoptotic protein cleaved caspase 3. Our results indicate that Hh signaling is not induced directly by HPV-encoded proteins but rather that Hh-activating mutations are selected in cells initially immortalized by HPV. Sonic Hedgehog (Shh) ligand induces proliferation and promotes migration of the cervical cancer cells studied. Together, these results indicate pro-survival and protective roles of an activated Hh signaling pathway in cervical cancer-derived cells, and suggest that inhibition of this pathway may be a therapeutic option in fighting cervical cancer.

  19. Adipose-derived mesenchymal stem cell administration does not improve corneal graft survival outcome.

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    Sherezade Fuentes-Julián

    Full Text Available The effect of local and systemic injections of mesenchymal stem cells derived from adipose tissue (AD-MSC into rabbit models of corneal allograft rejection with either normal-risk or high-risk vascularized corneal beds was investigated. The models we present in this study are more similar to human corneal transplants than previously reported murine models. Our aim was to prevent transplant rejection and increase the length of graft survival. In the normal-risk transplant model, in contrast to our expectations, the injection of AD-MSC into the graft junction during surgery resulted in the induction of increased signs of inflammation such as corneal edema with increased thickness, and a higher level of infiltration of leukocytes. This process led to a lower survival of the graft compared with the sham-treated corneal transplants. In the high-risk transplant model, in which immune ocular privilege was undermined by the induction of neovascularization prior to graft surgery, we found the use of systemic rabbit AD-MSCs prior to surgery, during surgery, and at various time points after surgery resulted in a shorter survival of the graft compared with the non-treated corneal grafts. Based on our results, local or systemic treatment with AD-MSCs to prevent corneal rejection in rabbit corneal models at normal or high risk of rejection does not increase survival but rather can increase inflammation and neovascularization and break the innate ocular immune privilege. This result can be partially explained by the immunomarkers, lack of immunosuppressive ability and immunophenotypical secretion molecules characterization of AD-MSC used in this study. Parameters including the risk of rejection, the inflammatory/vascularization environment, the cell source, the time of injection, the immunosuppression, the number of cells, and the mode of delivery must be established before translating the possible benefits of the use of MSCs in corneal transplants to clinical

  20. Ubiquitin is associated with the survival of ectopic stromal cells in endometriosis

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    Bebington Catherine R

    2004-09-01

    Full Text Available Abstract Background Endometriosis is a condition that affects women of reproductive age, where the glandular and/or stromal tissues from the eutopic endometrium implant in ectopic locations. It is well established that the survival of ectopic implants is due to lower levels of apoptosis, but no consensus exists as to which pathway/s this is mediated by. The ubiquitin protein shares a similar sequence homology to an anti-apoptotic protein called BAG-1 and is expressed in the normal endometrium. Currently, no studies have been conducted to determine ubiquitin expression and its possible anti-apoptotic effects in endometriosis. Methods Archived endometrial tissues from endometriosis patients and women undergoing laparoscopic diagnosis (controls from January 2000 to July 2003 at Westmead Hospital were examined, where 14 cases of endometriosis and 55 controls were included in the study. Results Both the ubiquitin protein and apoptosis were expressed in both glandular and stromal cells throughout the menstrual cycle of the eutopic endometrium, in which ubiquitin exhibited a cyclic expression, reaching a peak in late proliferative phase. In contrast, ubiquitin was predominantly expressed in cells of stromal origin in endometriosis, was no longer regulated by a cyclic pattern and was associated with an aberrant level of cell survival. Conclusions For the first time, this study shows that ubiquitin is expressed in endometriotic cells and may contribute to a reduced sensitivity of ectopic endometrial tissue to apoptosis. These findings also suggest that stromal cells contribute differentially to the development of ectopic endometrial tissue.

  1. BMP9-Induced Survival Effect in Liver Tumor Cells Requires p38MAPK Activation

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    María García-Álvaro

    2015-08-01

    Full Text Available The study of bone morphogenetic proteins (BMPs role in tumorigenic processes, and specifically in the liver, has gathered importance in the last few years. Previous studies have shown that BMP9 is overexpressed in about 40% of hepatocellular carcinoma (HCC patients. In vitro data have also shown evidence that BMP9 has a pro-tumorigenic action, not only by inducing epithelial to mesenchymal transition (EMT and migration, but also by promoting proliferation and survival in liver cancer cells. However, the precise mechanisms driving these effects have not yet been established. In the present work, we deepened our studies into the intracellular mechanisms implicated in the BMP9 proliferative and pro-survival effect on liver tumor cells. In HepG2 cells, BMP9 induces both Smad and non-Smad signaling cascades, specifically PI3K/AKT and p38MAPK. However, only the p38MAPK pathway contributes to the BMP9 growth-promoting effect on these cells. Using genetic and pharmacological approaches, we demonstrate that p38MAPK activation, although dispensable for the BMP9 proliferative activity, is required for the BMP9 protective effect on serum withdrawal-induced apoptosis. These findings contribute to a better understanding of the signaling pathways involved in the BMP9 pro-tumorigenic role in liver tumor cells.

  2. Lipocalin-2-induced cytokine production enhances endometrial carcinoma cell survival and migration

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    Hsiu-Hsia Lin, Chi-Jr Liao, Ying-Chu Lee, Keng-Hsun Hu, Hsien-Wei Meng, Sin-Tak Chu

    2011-01-01

    Full Text Available Lipocalin-2 (Lcn-2 is an acute-phase protein that has been implicated in diverse physiological processes in mice, including: apoptosis, ion transport, inflammation, cell survival, and tumorigenesis. This study characterized the biological activity of Lcn-2 in human endometrial carcinoma cells (RL95-2. Exposure of RL95-2 cells to Lcn-2 for >24 h reduced Lcn-2-induced cell apoptosis, changed the cell proliferation and up-regulated cytokine secretions, including: interleukin-8 (IL-8, inteleukin-6 (IL-6, monocyte chemotatic protein-1 (MCP-1 and growth-related oncogene (GRO. However, IL-8 mRNA and protein levels were dramatically increased in Lcn-2-treated RL95-2 cells. To determine the IL-8 effect on Lcn-2-treated RL95-2 cells was our major focus. Adding recombinant IL-8 (rIL-8 resulted in decreased caspase-3 activity in Lcn-2-treated cells, whereas the addition of IL-8 antibodies resulted in significantly increased caspase-3 activity and decreased cell migration. Data indicate that IL-8 plays a crucial role in the induction of cell migration. Interestingly, Lcn-2-induced cytokines, secretion from RL95-2 cells, could not show the potent cell migration ability with the exception of IL-8. We conclude that Lcn-2 triggered cytokine secretions to prevent RL95-2 cells from undergoing apoptosis and subsequently increased cell migration. We hypothesize that Lcn-2 increased cytokine secretion by RL95-2 cells, which in turn activated a cellular defense system. This study suggests that Lcn-2 may play a role in the human female reproductive system or in endometrial cancer.

  3. Expressions of topoisomerase IIα and BCRP in metastatic cells are associated with overall survival in small cell lung cancer patients.

    Science.gov (United States)

    Rijavec, Matija; Silar, Mira; Triller, Nadja; Kern, Izidor; Cegovnik, Urška; Košnik, Mitja; Korošec, Peter

    2011-09-01

    The aim of this study was to investigate the mRNA expression levels of multidrug resistance-associated proteins in chemo-naïve metastatic lung cancer cells and to determine the correlation with response to chemotherapy and overall survival. Metastatic cells were obtained by transbronchial fine needle aspiration biopsy of enlarged mediastinal lymph nodes in 14 patients with small cell lung cancer (SCLC) and 7 patients with non-small cell lung cancer (NSCLC). After cytological confirmation of lung cancer type, total RNA was extracted from biopsy samples and reverse transcribed to cDNA, and real-time PCR for the genes of interest [P-glycoprotein (P-gp), multidrug resistance protein 1 (MRP1), breast cancer resistance protein (BCRP), lung resistance protein (LRP) and topoisomerase IIα (TOPIIα)], was performed. We observed significantly decreased expression of BCRP and significantly increased expression of TOPIIα in metastatic SCLC cells compared to NSCLC. Furthermore, in SCLC high topoisomerase IIα and low BCRP expression levels positively correlated with longer overall survival. Our results showed higher expression levels of BCRP as well as lower levels of topoisomerase IIα in chemo-naïve metastatic cells in NSCLC than in SCLC. These results correlate with previous observations that metastatic SCLC cells at the beginning of chemotherapy are potentially more sensitive to chemotherapeutic agents while in metastatic NSCLC cells resistance is usually inherent. We also showed that altered levels of topoisomerase IIα and BCRP in SCLC are important factors that contribute to resistance to chemotherapeutics that interfere with the enzyme and/or DNA and are highly associated with overall survival.

  4. TPD52 represents a survival factor in ERBB2-amplified breast cancer cells.

    Science.gov (United States)

    Roslan, Nuruliza; Bièche, Ivan; Bright, Robert K; Lidereau, Rosette; Chen, Yuyan; Byrne, Jennifer A

    2014-10-01

    TPD52 and ERBB2 co-expression has been persistently reported in human breast cancer and animal models of this disease, but the significance of this is unknown. We identified significant positive associations between relative TPD52 and ERBB2 transcript levels in human diagnostic breast cancer samples, and maximal TPD52 expression in the hormone receptor (HR)- and ERBB2-positive sub-group. High-level TPD52 expression was associated with significantly reduced metastasis-free survival, within the overall cohort (log rank test, P = 8.6 × 10(-4), n = 375) where this was an independent predictor of metastasis-free survival (hazard ratio, 2.69, 95% confidence interval 1.59-4.54, P = 2.2 × 10(-4), n = 359), and the HR- and ERBB2-positive sub-group (log rank test, P = 0.035, n = 47). Transient TPD52 knock-down in the ERBB2-amplified breast cancer cell lines SK-BR-3 and BT-474 produced significant apoptosis, both singly and in combination with transient ERBB2 knock-down. Unlike ERBB2 knock-down, transient TPD52 knock-down produced no reduction in pAKT levels in SK-BR-3 or BT-474 cells. We then derived multiple SK-BR-3 cell lines in which TPD52 levels were stably reduced, and measured significant inverse correlations between pERBB2 and TPD52 levels in viable TPD52-depleted and control cell lines, all of which showed similar proliferative capacities. Our results therefore identify TPD52 as a survival factor in ERBB2-amplified breast cancer cells, and suggest complementary cellular functions for TPD52 and ERBB2.

  5. Fludarabine nucleoside modulates nuclear "survival and death" proteins in resistant chronic lymphocytic leukemia cells.

    Science.gov (United States)

    Henrich, Silke; Mactier, Swetlana; Best, Giles; Mulligan, Stephen P; Crossett, Ben; Christopherson, Richard Ian

    2011-12-01

    The nuclear mechanisms by which fludarabine nucleoside (F-ara-A) induces apoptosis have been investigated in human MEC1 cells derived from B-cell chronic lymphocytic leukemia. Upon treatment of cells with F-ara-A (100 μM, 72 hours), 15 nuclear proteins changed in abundance by more than 2-fold. Nuclear proteins up-regulated included calmodulin (4.3-fold), prohibitin (3.9-fold), β-actin variant (3.7-fold), and structure-specific recognition protein 1 (3.7-fold); those down-regulated included 60S ribosomal protein P2B (0.12-fold), fumarate hydratase (0.19-fold), splicing factor arginine/serine-rich 3 (0.35-fold), and replication protein A2 (0.42-fold). These changes in the levels of specific proteins promote survival or apoptosis; because the end result is apoptosis of MEC1 cells, apoptotic effects predominate.

  6. CTLA-4 blockade during dendritic cell based booster vaccination influences dendritic cell survival and CTL expansion

    DEFF Research Database (Denmark)

    Pedersen, Anders E; Ronchese, Franca

    2007-01-01

    Dendritic cells (DCs) are potent antigen-presenting cells and critical for the priming of CD8+ T cells. Therefore the use of these cells as adjuvant cells has been tested in a large number of experimental and clinical vaccination studies, in particular cancer vaccine studies. A number of protocols...

  7. Tumour infiltrating lymphocytes correlate with improved survival in patients with esophageal squamous cell carcinoma.

    Science.gov (United States)

    Jiang, Dongxian; Liu, Yalan; Wang, Hao; Wang, Haixing; Song, Qi; Sujie, Akesu; Huang, Jie; Xu, Yifan; Zeng, Haiying; Tan, Lijie; Hou, Yingyong; Xu, Chen

    2017-03-21

    We undertook a study of tumour infiltrating lymphocytes (TILs) in a large and relatively homogeneous group of patients with completely resected esophageal squamous cell carcinoma (ESCC). Hematoxylin and eosin-stained sections of 235 ESCC tumours were evaluated for density of TILs in intratumoural (iTIL) and stromal compartments (sTIL). Foxp3+, CD4+, and CD8+ T cells in tumoural and stromal areas were evaluated by immunohistochemistry. Of the 235 tumours, high sTIL (>10%), and iTIL (>10%) were observed in 101 (43.0%) and 98 (41.7%), respectively. The median follow-up period was 36.0 months (95% CI 29.929-42.071). Univariate analysis revealed that sTIL (>10%), iTIL (>20%), vessels involvement, lymph node metastasis, and clinical stage were significantly associated with postoperative outcome. In multivariate analysis, high sTIL (HR: 0.664, P = 0.019 for Disease free survival; HR: 0.608, P = 0.005 for Overall survival) was identified as independent better prognostic factor. Further analysis, sTIL was identified as independently prognostic factor in Stage III-IVa disease, which was not found in Stage I-II disease. Our study demonstrated that sTIL was associated with better ESCC patients' survival, especially in Stage III-IVa disease. Assessment of sTIL could be useful to discriminate biological behavior for ESCC patients.

  8. Long-term Survival, Organ Function, and Malignancy after Hematopoietic Stem Cell Transplantation for Fanconi Anemia.

    Science.gov (United States)

    Bonfim, Carmem; Ribeiro, Lisandro; Nichele, Samantha; Bitencourt, Marco; Loth, Gisele; Koliski, Adriana; Funke, Vaneuza A M; Pilonetto, Daniela V; Pereira, Noemi F; Flowers, Mary E D; Velleuer, Eunike; Dietrich, Ralf; Fasth, Anders; Torres-Pereira, Cassius C; Pedruzzi, Paola; Eapen, Mary; Pasquini, Ricardo

    2016-07-01

    We report on long-term survival in 157 patients with Fanconi anemia (FA) who survived 2 years or longer after their first transplantation with a median follow-up of 9 years. Marrow failure (80%) was the most common indication for transplantation. There were 20 deaths beyond 2 years after transplantation, with 12 of the deaths occurring beyond 5 years after transplantation. Donor chimerism was available for 149 patients: 112 (76%) reported > 95% chimerism, 27 (18%) reported 90% to 95% chimerism, and 8 (5%) reported 20% to 89% donor chimerism. Two patients have < 20% donor chimerism. The 10- and 15-year probabilities of survival were 90% and 79%, respectively. Results of multivariate analysis showed higher mortality risks for transplantations before 2003 (hazard ratio [HR], 7.87; P = .001), chronic graft-versus-host disease (GVHD) (HR, 3.80; P = .004) and squamous cell carcinoma after transplantation (HR, 38.17; P < .0001). The predominant cause of late mortality was squamous cell carcinoma, with an incidence of 8% and 14% at 10 and 15 years after transplantation, respectively, and was more likely to occur in those with chronic GVHD. Other causes of late mortality included chronic GVHD, infection, graft failure, other cancers, and hemorrhage. Although most patients are disease free and functional long term, our data support aggressive surveillance for long periods to identify those at risk for late mortality.

  9. Cell surface characteristics enable encrustation-free survival of neutrophilic iron-oxidizing bacteria

    Science.gov (United States)

    Saini, G.; Chan, C. S.

    2011-12-01

    Microbial growth in mineralizing environments depends on the cells' ability to evade surface precipitation. Cell-mineral interactions may be required for metabolism, but if unmoderated, cells could become encrusted, which would limit diffusion of nutrients and waste across cell walls. A combination of cell surface charge and hydrophobicity could enable the survival of microbes in such environments by inhibiting mineral attachment. To investigate this mechanism, we characterized the surfaces of two neutrophilic iron-oxidizing bacteria (FeOB): Mariprofundus ferrooxydans, a Zetaproteobacterium from Fe(II)-rich submarine hydrothermal vents and a Betaproteobacterium Gallionellales strain R-1, recently isolated from a ferrous groundwater seep. Both bacteria produce iron oxyhydroxides, yet successfully escape surface encrustation while inhabiting milieu where iron minerals are also produced by abiotic processes. SEM-EDX and TEM-EELS analyses of cultured bacteria revealed no iron on the cell surfaces. Zeta potential measurements showed that these bacteria have very small negative surface charge (0 to -4 mV) over a pH range of 4-9, indicating near-neutrally charged surfaces. Water contact angle measurements and thermodynamic calculations demonstrate that both bacteria and abiotically-formed Fe oxhydroxides are hydrophilic. Extended-DLVO calculations showed that hydrophilic repulsion between cells and minerals dominates over electrostatic and Lifshitz-van der Waals interactions. This leads to overall repulsion between microbes and minerals, thus preventing surface encrustation. Low surface charge and hydrophilicity (determined by microbial adhesion to hydrocarbon assay) were common features for both live and azide-inhibited cells, which shows that surface characteristics do not depend on active metabolism. It is remarkable that these two phylogenetically-distant bacteria from different environments employ similar adaptations to prevent surface mineralization. Our results

  10. Anti-apoptotic BFL-1 is the major effector in activation-induced human mast cell survival.

    Directory of Open Access Journals (Sweden)

    Maria Ekoff

    Full Text Available Mast cells are best known for their role in allergic reactions, where aggregation of FcεRI leads to the release of mast cell mediators causing allergic symptoms. The activation also induces a survival program in the cells, i.e., activation-induced mast cell survival. The aim of the present study was to investigate how the activation-induced survival is mediated. Cord blood-derived mast cells and the mast cell line LAD-2 were activated through FcεRI crosslinking, with or without addition of chemicals that inhibit the activity or expression of selected Bcl-2 family members (ABT-737; roscovitine. Cell viability was assessed using staining and flow cytometry. The expression and function of Bcl-2 family members BFL-1 and MCL-1 were investigated using real-time quantitative PCR and siRNA treatment. The mast cell expression of Bfl-1 was investigated in skin biopsies. FcεRI crosslinking promotes activation-induced survival of human mast cells and this is associated with an upregulation of the anti-apoptotic Bcl-2 family member Bfl-1. ABT-737 alone or in combination with roscovitine decreases viability of human mast cells although activation-induced survival is sustained, indicating a minor role for Bcl-X(L, Bcl-2, Bcl-w and Mcl-1. Reducing BFL-1 but not MCL-1 levels by siRNA inhibited activation-induced mast cell survival. We also demonstrate that mast cell expression of Bfl-1 is elevated in birch-pollen-provocated skin and in lesions of atopic dermatitis and psoriasis patients. Taken together, our results highlight Bfl-1 as a major effector in activation-induced human mast cell survival.

  11. Survival Analysis of Non-Small Cell Lung Cancer in Patients Aged 70 and over

    Directory of Open Access Journals (Sweden)

    Jiankun SUN

    2008-04-01

    Full Text Available Background and Objective With a trend of worldwide increasing incidence of elderly population, more and more people pay close attention to diseases in the elderly. Lung cancer is a typical disease of the elderly patients. Around one-third of all patients with non-small cell lung cancer (NSCLC are over the age of 70. Many authors use the age 70 to define the elderly patients in lung cancer. The objective of this study is to evaluate the survival of patients older than 70 with NSCLC and explore the independent prognostic factors in this group of patients. Methods 148 elderly patients with NSCLC were reviewed. All the potential prognostic factors, including sex, age, smoke, symptoms, pathological types, clinical stage, ECOG performance status, complication, focus resection, radiotherapy and chemotherapy were analyzed by COX regression in SPSS 13.0 software. Results After 5-168 months follow-up, 119 patients died, the overall survival rate was 19.6%. 1,2,3,5-year survival rates were 43.2%, 19.0%, 9.0% and 5.4% respectively. Median survival time (MST was 9.29 moths. COX regression showed clinical stage (P=0.002, ECOG performance status (P=0.000, focus resection (P=0.012 and radiotherapy of primary site (P=0.012 were the independent prognostic factors. Conclusion The elderly patients with NSCLC in early stage and good performance status tend to have longer life expectance, whereas resection and radiotherapy of primary site can prolong the survival time (P<0.05.

  12. Progranulin is expressed within motor neurons and promotes neuronal cell survival

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    Kay Denis G

    2009-10-01

    Full Text Available Abstract Background Progranulin is a secreted high molecular weight growth factor bearing seven and one half copies of the cysteine-rich granulin-epithelin motif. While inappropriate over-expression of the progranulin gene has been associated with many cancers, haploinsufficiency leads to atrophy of the frontotemporal lobes and development of a form of dementia (frontotemporal lobar degeneration with ubiquitin positive inclusions, FTLD-U associated with the formation of ubiquitinated inclusions. Recent reports indicate that progranulin has neurotrophic effects, which, if confirmed would make progranulin the only neuroprotective growth factor that has been associated genetically with a neurological disease in humans. Preliminary studies indicated high progranulin gene expression in spinal cord motor neurons. However, it is uncertain what the role of Progranulin is in normal or diseased motor neuron function. We have investigated progranulin gene expression and subcellular localization in cultured mouse embryonic motor neurons and examined the effect of progranulin over-expression and knockdown in the NSC-34 immortalized motor neuron cell line upon proliferation and survival. Results In situ hybridisation and immunohistochemical techniques revealed that the progranulin gene is highly expressed by motor neurons within the mouse spinal cord and in primary cultures of dissociated mouse embryonic spinal cord-dorsal root ganglia. Confocal microscopy coupled to immunocytochemistry together with the use of a progranulin-green fluorescent protein fusion construct revealed progranulin to be located within compartments of the secretory pathway including the Golgi apparatus. Stable transfection of the human progranulin gene into the NSC-34 motor neuron cell line stimulates the appearance of dendritic structures and provides sufficient trophic stimulus to survive serum deprivation for long periods (up to two months. This is mediated at least in part through

  13. Mechanisms of Sensorineural Cell Damage, Death and Survival in the Cochlea

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    Allen Frederic Ryan

    2015-04-01

    Full Text Available The majority of acquired hearing loss, including presbycusis, is caused by irreversible damage to the sensorineural tissues of the cochlea. This article reviews the intracellular mechanisms that contribute to sensorineural damage in the cochlea, as well as the survival signaling pathways that can provide endogenous protection and tissue rescue. These data have primarily been generated in hearing loss not directly related to age. However, there is evidence that similar mechanisms operate in presbycusis. Moreover, accumulation of damage from other causes can contribute to age-related hearing loss. Potential therapeutic interventions to balance opposing but interconnected cell damage and survival pathways, such as antioxidants, anti-apoptotics, and pro-inflammatory cytokine inhibitors, are also discussed.

  14. Functional role of autophagy-mediated proteome remodeling in cell survival signaling and innate immunity.

    Science.gov (United States)

    Mathew, Robin; Khor, Sinan; Hackett, Sean R; Rabinowitz, Joshua D; Perlman, David H; White, Eileen

    2014-09-18

    Ras-driven cancer cells upregulate basal autophagy that degrades and recycles intracellular proteins and organelles. Autophagy-mediated proteome degradation provides free amino acids to support metabolism and macromolecular synthesis, which confers a survival advantage in starvation and promotes tumorigenesis. While the degradation of isolated protein substrates by autophagy has been implicated in controlling cellular function, the extent and specificity by which autophagy remodels the cellular proteome and the underlying functional consequences were unknown. Here we compared the global proteome of autophagy-functional and -deficient Ras-driven cancer cells, finding that autophagy affects the majority of the proteome yet is highly selective. While levels of vesicle trafficking proteins important for autophagy are preserved during starvation-induced autophagy, deleterious inflammatory response pathway components are eliminated even under basal conditions, preventing cytokine-induced paracrine cell death. This reveals the global, functional impact of autophagy-mediated proteome remodeling on cell survival and identifies critical autophagy substrates that mediate this process.

  15. Radiation-induced PGE2 sustains human glioma cells growth and survival through EGF signaling.

    Science.gov (United States)

    Brocard, Emeline; Oizel, Kristell; Lalier, Lisenn; Pecqueur, Claire; Paris, François; Vallette, François M; Oliver, Lisa

    2015-03-30

    Glioblastoma Multiforme (GBM) is the most common brain cancer in adults. Radiotherapy (RT) is the most effective post-operative treatment for the patients even though GBM is one of the most radio-resistant tumors. Dead or dying cells within the tumor are thought to promote resistance to treatment through mechanisms that are very poorly understood. We have evaluated the role of Prostaglandin E2 (PGE2), a versatile bioactive lipid, in GBM radio-resistance. We used an in vitro approach using 3D primary cultures derived from representative GBM patients. We show that irradiated glioma cells produced and released PGE2 in important quantities independently of the induction of cell death. We demonstrate that the addition of PGE2 enhances cell survival and proliferation though its ability to trans-activate the Epithelial Growth Factor receptor (EGFR) and to activate β-catenin. Indeed, PGE2 can substitute for EGF to promote primary cultures survival and growth in vitro and the effect is likely to occur though the Prostaglandin E2 receptor EP2.

  16. Radiation-induced PGE2 sustains human glioma cell growth and survival through EGF signaling

    Science.gov (United States)

    Lalier, Lisenn; Pecqueur, Claire; Paris, François; Vallette, François M.; Oliver, Lisa

    2015-01-01

    Glioblastoma Multiforme (GBM) is the most common brain cancer in adults. Radiotherapy (RT) is the most effective post-operative treatment for the patients even though GBM is one of the most radio-resistant tumors. Dead or dying cells within the tumor are thought to promote resistance to treatment through mechanisms that are very poorly understood. We have evaluated the role of Prostaglandin E2 (PGE2), a versatile bioactive lipid, in GBM radio-resistance. We used an in vitro approach using 3D primary cultures derived from representative GBM patients. We show that irradiated glioma cells produced and released PGE2 in important quantities independently of the induction of cell death. We demonstrate that the addition of PGE2 enhances cell survival and proliferation though its ability to trans-activate the Epithelial Growth Factor receptor (EGFR) and to activate β-catenin. Indeed, PGE2 can substitute for EGF to promote primary cultures survival and growth in vitro and the effect is likely to occur though the Prostaglandin E2 receptor EP2. PMID:25749386

  17. Hypoxia Inducible Factor Pathway and Physiological Adaptation: A Cell Survival Pathway?

    Science.gov (United States)

    Kumar, Hemant; Choi, Dong-Kug

    2015-01-01

    Oxygen homeostasis reflects the constant body requirement to generate energy. Hypoxia (0.1-1% O2), physioxia or physoxia (∼1-13%), and normoxia (∼20%) are terms used to define oxygen concentration in the cellular environment. A decrease in oxygen (hypoxia) or excess oxygen (hyperoxia) could be deleterious for cellular adaptation and survival. Hypoxia can occur under both physiological (e.g., exercise, embryonic development, underwater diving, or high altitude) and pathological conditions (e.g., inflammation, solid tumor formation, lung disease, or myocardial infarction). Hypoxia plays a key role in the pathophysiology of heart disease, cancers, stroke, and other causes of mortality. Hypoxia inducible factor(s) (HIFs) are key oxygen sensors that mediate the ability of the cell to cope with decreased oxygen tension. These transcription factors regulate cellular adaptation to hypoxia and protect cells by responding acutely and inducing production of endogenous metabolites and proteins to promptly regulate metabolic pathways. Here, we review the role of the HIF pathway as a metabolic adaptation pathway and how this pathway plays a role in cell survival. We emphasize the roles of the HIF pathway in physiological adaptation, cell death, pH regulation, and adaptation during exercise.

  18. Quercetin supplementation restores testicular function and augments germ cell survival in the estrogenized rats.

    Science.gov (United States)

    Bharti, Shilpa; Misro, M M; Rai, Umesh

    2014-03-05

    Quercetin, as a flavonoid, has been recognized to possess dual properties of an oxidant and antioxidant as well. The role of quercetin (QC), as an antioxidant in countering estradiol-3-benzoate (EB) induced adverse effects and germ cell apoptosis in adult rat testis was presently investigated. Adult rats received EB (0.075 mg/rat/5th day) alone or EB+QC (15 mg/kg bw/alternate day) simultaneously for 30 days. Revival of spermatogenesis following QC intervention was associated with a significant restoration in serum and intra-testicular levels of testosterone. Decline in lipid peroxidation and simultaneous improvement in the activities of superoxide dismutase, catalase and glutathione s-transferase were very much evident. Identically, total antioxidant capacity and glutathione demonstrated a marked improvement. QC augmented germ cell survival leading to a decrease in cell apoptosis. Expression of downstream apoptotic markers, caspase-3 and poly-ADP-ribose polymerase (PARP) presented a significant reduction. Down regulation with respect to upstream markers, caspase-8 and -9, Fas, FasL, Bax, and p53 was similarly observed. Taken together, the above findings indicate that with the dose presently used quercetin with its antioxidant and antiestrogenic properties restored testicular function leading to revival of spermatogenesis. It also augmented germ cell survival primarily mediated through downregulation in the expressions of upstream, downstream and other markers in the pathways of metazoan apoptosis.

  19. Karyopherin Alpha 1 Regulates Satellite Cell Proliferation and Survival by Modulating Nuclear Import.

    Science.gov (United States)

    Choo, Hyo-Jung; Cutler, Alicia; Pavlath, Grace K

    2016-07-19

    Satellite cells are stem cells with an essential role in skeletal muscle repair. Precise regulation of gene expression is critical for proper satellite cell quiescence, proliferation, differentiation and self-renewal. Nuclear proteins required for gene expression are dependent on the nucleocytoplasmic transport machinery to access to nucleus, however little is known about regulation of nuclear transport in satellite cells. The best characterized nuclear import pathway is classical nuclear import which depends on a classical nuclear localization signal (cNLS) in a cargo protein and the heterodimeric import receptors, karyopherin alpha (KPNA) and beta (KPNB). Multiple KPNA1 paralogs exist and can differ in importing specific cNLS proteins required for cell differentiation and function. We show that transcripts for six Kpna paralogs underwent distinct changes in mouse satellite cells during muscle regeneration accompanied by changes in cNLS proteins in nuclei. Depletion of KPNA1, the most dramatically altered KPNA, caused satellite cells in uninjured muscle to prematurely activate, proliferate and undergo apoptosis leading to satellite cell exhaustion with age. Increased proliferation of satellite cells led to enhanced muscle regeneration at early stages of regeneration. In addition, we observed impaired nuclear localization of two key KPNA1 cargo proteins: p27, a cyclin-dependent kinase inhibitor associated with cell cycle control and lymphoid enhancer factor 1, a critical cotranscription factor for β-catenin. These results indicate that regulated nuclear import of proteins by KPNA1 is critical for satellite cell proliferation and survival and establish classical nuclear import as a novel regulatory mechanism for controlling satellite cell fate. Stem Cells 2016.

  20. Thermal survival characteristics of cell subpopulations isolated from a heterogeneous human colon tumor.

    Science.gov (United States)

    Leith, J T; Heyman, P; DeWyngaert, J K; Dexter, D L; Calabresi, P; Glicksman, A S

    1983-07-01

    Responses of a heterogeneous human colon adenocarcinoma model tumor system to in vitro hyperthermic treatment at various temperatures have been studied. This model tumor system consists of an original tumor line (DLD-1) obtained from surgical biopsy, and two derivative subpopulations termed clones A and D. These 3 tumor cell populations differ in many properties, including karyotype and DNA content, production of specific antigens, and sensitivities to other cytotoxic agents such as chemotherapeutic drugs and X-irradiation. In these experiments, exponentially growing tumor cells were exposed to hyperthermia (42.2, 42.5, 43.0, 44.0, or 45.0 degrees) for graded time periods. A single-hit, multitarget equation was used to express the dependence of survival on time at a given temperature, and values for extrapolation numbers, quasi-threshold time (min), and T0 (mean lethal time; min) were obtained for the initial regions of survival. At the lower temperatures of 42.2 and 42.5 degrees, biphasic survival curves were obtained for all three tumor lines and, as a consequence, a second mean lethal time (T0,f) was also determined for the final thermal-resistant portion of the survival curves. Using the T0 values as an index of relative resistance, values at 42.2 and 42.5 degrees indicated that, in this temperature region, the parent (DLD-1) line was the most sensitive, the clone A line showed intermediate sensitivity, and the clone D line was the most resistant. In the thermally resistant portion of the survival curve, T0 values indicated that the clone A subpopulation was the most sensitive, the DLD-1 line showed intermediate sensitivity, and the clone D tumor subpopulation remained the most resistant. At the higher temperatures of 43, 44, and 45 degrees, in which thermotolerance is not observed during heat treatment, values for T0 indicated the parent (DLD-1) tumor line was still the most sensitive tumor line, and the clone A and clone D lines showed approximately equal

  1. Endotoxin-stimulated Rat Hepatic Stellate Cells Induce Autophagy in Hepatocytes as a Survival Mechanism.

    Science.gov (United States)

    Dangi, Anil; Huang, Chao; Tandon, Ashish; Stolz, Donna; Wu, Tong; Gandhi, Chandrashekhar R

    2016-01-01

    Bacterial lipopolysaccharide (LPS)-stimulated hepatic stellate cells (HSCs) produce many cytokines including IFNβ, TNFα, and IL6, strongly inhibit DNA synthesis, but induce apoptosis of a small number of hepatocytes. In vivo administration of LPS (up to 10 mg/mL) causes modest inflammation and weight loss in rats but not mortality. We determined whether LPS-stimulated HSCs instigate mechanisms of hepatocyte survival. Rats received 10 mg/kg LPS (i.p.) and determinations were made at 6 h. In vitro, HSCs were treated with 100 ng/mL LPS till 24 h. The medium was transferred to hepatocytes, and determinations were made at 0-12 h. Controls were HSC-conditioned medium or medium-containing LPS. LPS treatment of rats caused autophagy in hepatocytes, a physiological process for clearance of undesirable material including injured or damaged organelles. This was accompanied by activation of c-Jun NH2 terminal kinase (JNK) and apoptosis of ~4-5% of hepatocytes. In vitro, LPS-conditioned HSC medium (LPS/HSC) induced autophagy in hepatocytes but apoptosis of only ~10% of hepatocytes. While LPS/HSC stimulated activation of JNK (associated with cell death), it also activated NFkB and ERK1/2 (associated with cell survival). LPS-stimulated HSCs produced IFNβ, and LPS/HSC-induced autophagy in hepatocytes and their apoptosis were significantly inhibited by anti-IFNβ antibody. Blockade of autophagy, on the other hand, strongly augmented hepatocyte apoptosis. While LPS-stimulated HSCs cause apoptosis of a subpopulation of hepatocytes by producing IFNβ, they also induce cell survival mechanisms, which may be of critical importance in resistance to liver injury during endotoxemia.

  2. Ciprofloxacin Derivatives Affect Parasite Cell Division and Increase the Survival of Mice Infected with Toxoplasma gondii

    Science.gov (United States)

    Martins-Duarte, Erica S.; Dubar, Faustine; Lawton, Philippe; França da Silva, Cristiane; C. Soeiro, Maria de Nazaré; de Souza, Wanderley; Biot, Christophe; Vommaro, Rossiane C.

    2015-01-01

    Toxoplasmosis, caused by the protozoan Toxoplasma gondii, is a worldwide disease whose clinical manifestations include encephalitis and congenital malformations in newborns. Previously, we described the synthesis of new ethyl-ester derivatives of the antibiotic ciprofloxacin with ~40-fold increased activity against T. gondii in vitro, compared with the original compound. Cipro derivatives are expected to target the parasite’s DNA gyrase complex in the apicoplast. The activity of these compounds in vivo, as well as their mode of action, remained thus far uncharacterized. Here, we examined the activity of the Cipro derivatives in vivo, in a model of acute murine toxoplasmosis. In addition, we investigated the cellular effects T. gondii tachyzoites in vitro, by immunofluorescence and transmission electron microscopy (TEM). When compared with Cipro treatment, 7-day treatments with Cipro derivatives increased mouse survival significantly, with 13–25% of mice surviving for up to 60 days post-infection (vs. complete lethality 10 days post-infection, with Cipro treatment). Light microscopy examination early (6 and 24h) post-infection revealed that 6-h treatments with Cipro derivatives inhibited the initial event of parasite cell division inside host cells, in an irreversible manner. By TEM and immunofluorescence, the main cellular effects observed after treatment with Cipro derivatives and Cipro were cell scission inhibition - with the appearance of ‘tethered’ parasites – malformation of the inner membrane complex, and apicoplast enlargement and missegregation. Interestingly, tethered daughter cells resulting from Cipro derivatives, and also Cipro, treatment did not show MORN1 cap or centrocone localization. The biological activity of Cipro derivatives against C. parvum, an apicomplexan species that lacks the apicoplast, is, approximately, 50 fold lower than that in T. gondii tachyzoites, supporting that these compounds targets the apicoplast. Our results show

  3. SU-E-T-352: Why Is the Survival Rate Low in Oropharyngeal Squamous Cell Carcinoma?

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Z; Feng, Y; Rasmussen, K; Rice, J; Stephenson, S; Ferreira, Maria C [East Carolina University, Greenville, NC (United States); Liu, T [Baylor College of Medicine, Houston, TX (United States); Yuh, K [California Institute of Technology, Pasadena, CA (United States); Wang, R; Grecula, J [Case Western Reserve University, Cleveland, OH (United States); Lo, S [The Ohio State University, Columbus, OH (United States); Mayr, N; Yuh, W [University of Washington, Seattle, WA (United States)

    2014-06-01

    Purpose: Tumors are composed of a large number of clonogens that have the capability of indefinite reproduction. Even when there is complete clinical or radiographic regression of the gross tumor mass after treatment, tumor recurrence can occur if the clonogens are not completely eradicated by radiotherapy. This study was to investigate the colonogen number and its association with the tumor control probability (TCP) in oropharyngeal squamous cell carcinoma (OSCCA). Methods: A literature search was conducted to collect clinical information of patients with OSCCA, including the prescription dose, tumor volume and survival rate. The linear-quadratic (LQ) model was incorporated into TCP model for clinical data analysis. The total dose ranged from 60 to 70 Gy and tumor volume ranged from 10 to 50 cc. The TCP was calculated for each group according to tumor size and dose. The least χ{sup 2} method was used to fit the TCP calculation to clinical data while other LQ model parameters (α, β) were adopted from the literature, due to the limited patient data. Results: A total of 190 patients with T2–T4 OSCCA were included. The association with HPV was not available for all the patients. The 3-year survival rate was about 82% for T2 squamous cell carcinoma and 40% for advanced tumors. Fitting the TCP model to the survival data, the average clonogen number was 1.56×10{sup 12}. For the prescription dose of 70 Gy, the calculated TCP ranged from 40% to 90% when the tumor volume varied from 10 to 50 cc. Conclusion: Our data suggests variation between the clonogen number and TCP in OSCCA. Tumors with larger colonogen number tend to have lower TCP and therefore dose escalation above 70 Gy may be indicated in order to improve the TCP and survival rate. Our result will require future confirmation with a large number of patients.

  4. Survival Analysis in Patients with Non- metastatic Squamous Cell Carcinoma of the Urinary Bladder

    Directory of Open Access Journals (Sweden)

    Ahmed M. Abdel-Rahim

    2011-04-01

    Full Text Available Background: We conducted a retrospective analysis to evaluate overall survival(OAS and disease free survival (DFS rates in patients with squamous cell carcinoma of the urinary bladder according to different prognostic factors. Methods: This retrospective study analyzed the medical records of patients with non-metastatic squamous cell carcinoma of the urinary bladder. All men underwent radical cystectomy and women underwent anterior pelvic exentration. Most patients had postoperative radiation therapy. The log-rank test examined differences in OASand DFS rates. Results: The medical records of 106 patients were analyzed. The median follow-up from the date of enrollment was 30 months and ranged from 2 to 73 months. For the entire group, three-year OAS rates were 46.9% and DFS rates were 44%. For patients with P2 (tumor invasion into the muscularis propria the three-year OAS rate was 53%, for P3 (tumor invasion into perivesical fat it was 45% and 9% for P4 (tumor invasion into adjacent organs, pelvic wall or abdominal wall The OAS rate was statistically significant in favor of P2 disease (P=0.0041. The three-year DFS rate was 50% for P2, 45% for P3 and 9% for P4 disease (P=0.0125. Administration of post-operative radiotherapy did not result in statistically significant improvement in three-year OASand DFS rates. Conclusion: Survival rates were statistically significant and higher in patients with P2 and P3 disease compared to P4 disease. Adjuvant radiotherapy did not result in statistically significant survival improvement.

  5. MicroRNA-22 promotes cell survival upon UV radiation by repressing PTEN

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Guangyun [Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, Memphis, TN (United States); Center for Adult Cancer Research, University of Tennessee Health Science Center, Memphis, TN (United States); Jilin Province Key Laboratory of Animal Embryo Engineering, Jilin University, Changchun (China); Shi, Yuling [Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, Memphis, TN (United States); Center for Adult Cancer Research, University of Tennessee Health Science Center, Memphis, TN (United States); Wu, Zhao-Hui, E-mail: zwu6@uthsc.edu [Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, Memphis, TN (United States); Center for Adult Cancer Research, University of Tennessee Health Science Center, Memphis, TN (United States)

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer miR-22 is induced in cells treated with UV radiation. Black-Right-Pointing-Pointer ATM is required for miR-22 induction in response to UV. Black-Right-Pointing-Pointer miR-22 targets 3 Prime -UTR of PTEN to repress its expression in UV-treated cells. Black-Right-Pointing-Pointer Upregulated miR-22 inhibits apoptosis in cells exposed to UV. -- Abstract: DNA damage response upon UV radiation involves a complex network of cellular events required for maintaining the homeostasis and restoring genomic stability of the cells. As a new class of players involved in DNA damage response, the regulation and function of microRNAs in response to UV remain poorly understood. Here we show that UV radiation induces a significant increase of miR-22 expression, which appears to be dependent on the activation of DNA damage responding kinase ATM (ataxia telangiectasia mutated). Increased miR-22 expression may result from enhanced miR-22 maturation in cells exposed to UV. We further found that tumor suppressor gene phosphatase and tensin homolog (PTEN) expression was inversely correlated with miR-22 induction and UV-induced PTEN repression was attenuated by overexpression of a miR-22 inhibitor. Moreover, increased miR-22 expression significantly inhibited the activation of caspase signaling cascade, leading to enhanced cell survival upon UV radiation. Collectively, these results indicate that miR-22 is an important player in the cellular stress response upon UV radiation, which may promote cell survival via the repression of PTEN expression.

  6. IMMUNE MODULATORY EFFECTS of HUMAN CHORIONIC GONADOTROPIN on DENDRITIC CELLS SUPPORTING FETAL SURVIVAL in MURINE PREGNANCY

    Directory of Open Access Journals (Sweden)

    Dominique Dauven

    2016-11-01

    Full Text Available Dendritic cells (DCs are critically involved in the determination of immunity versus tolerance. Hence, DCs are key regulators of immune responses either favoring or disfavoring fetal survival. Several factors were proposed to modulate DC phenotype and function during preg-nancy. Here, we studied whether the pregnancy hormone human Chorionic Gonadotropin (hCG is involved in DC regulation.In vitro, bone-marrow-derived DCs (BMDCs were stimulated in the presence or absence of urine-purified (uhCG or recombinant hCG (rhCG preparations. Subsequently, BMDC matu-ration was assessed. Cytokine secretion of activated BMDCs and their capability to enforce TH1, TH2, TH17 or Treg cell differentiation was determined after rhCG treatment. Moreover, the in vivo potential of hCG-modulated BMDCs to influence pregnancy outcome, Treg cell number and local cytokine expression was evaluated after adoptive transfer in a murine abor-tion-prone model before and after conception. Both hCG preparations impaired the maturation process of BMDCs. rhCG treatment did nei-ther alter cytokine secretion by BMDCs nor their ability to drive TH1, TH2 or TH17 differen-tiation. rhCG-treated BMDCs augmented the number of Treg cells within the T cell popula-tion. Adoptive transfer of rhCG-treated BMDCs after conception did not influence pregnancy outcome. However, transfer of hCG-treated BMDCs prior to mating had a protective effect on pregnancy. This positive effect was accompanied by increased Treg cell numbers and decidual IL-10 and TGF-β expression. Our results unveil the importance of hCG in retaining DCs in a tolerogenic state, thereby promoting Treg cell increment and supporting fetal survival.

  7. Immune Modulatory Effects of Human Chorionic Gonadotropin on Dendritic Cells Supporting Fetal Survival in Murine Pregnancy

    Science.gov (United States)

    Dauven, Dominique; Ehrentraut, Stefanie; Langwisch, Stefanie; Zenclussen, Ana Claudia; Schumacher, Anne

    2016-01-01

    Dendritic cells (DCs) are critically involved in the determination of immunity vs. tolerance. Hence, DCs are key regulators of immune responses either favoring or disfavoring fetal survival. Several factors were proposed to modulate DC phenotype and function during pregnancy. Here, we studied whether the pregnancy hormone human chorionic gonadotropin (hCG) is involved in DC regulation. In vitro, bone marrow-derived DCs (BMDCs) were stimulated in the presence or absence of urine-purified or recombinant hCG (rhCG) preparations. Subsequently, BMDC maturation was assessed. Cytokine secretion of activated BMDCs and their capability to enforce TH1, TH2, TH17, or Treg cell differentiation was determined after rhCG treatment. Moreover, the in vivo potential of hCG-modulated BMDCs to influence pregnancy outcome, Treg cell number, and local cytokine expression was evaluated after adoptive transfer in a murine abortion-prone model before and after conception. Both hCG preparations impaired the maturation process of BMDCs. rhCG treatment did neither alter cytokine secretion by BMDCs nor their ability to drive TH1, TH2, or TH17 differentiation. rhCG-treated BMDCs augmented the number of Treg cells within the T cell population. Adoptive transfer of rhCG-treated BMDCs after conception did not influence pregnancy outcome. However, transfer of hCG-treated BMDCs prior to mating had a protective effect on pregnancy. This positive effect was accompanied by increased Treg cell numbers and decidual IL-10 and TGF-β expression. Our results unveil the importance of hCG in retaining DCs in a tolerogenic state, thereby promoting Treg cell increment and supporting fetal survival. PMID:27895621

  8. Role of Ku80-dependent end-joining in delayed genomic instability in mammalian cells surviving ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Keiji, E-mail: kzsuzuki@nagasaki-u.ac.jp [Course of Life Sciences and Radiation Research, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Kodama, Seiji [Research Institute for Advanced Science and Technology, Osaka Prefecture University, 1-2 Gakuen-machi, Sakai 599-8570 (Japan); Watanabe, Masami [Kyoto University Research Reactor Institute, Kumatori-cho Sennan-gun, Osaka 590-0494 (Japan)

    2010-01-05

    Ionizing radiation induces delayed destabilization of the genome in the progenies of surviving cells. This phenomenon, which is called radiation-induced genomic instability, is manifested by delayed induction of radiation effects, such as cell death, chromosome aberration, and mutation in the progeny of cells surviving radiation exposure. Previously, there was a report showing that delayed cell death was absent in Ku80-deficient Chinese hamster ovary (CHO) cells, however, the mechanism of their defect has not been determined. We found that delayed induction of DNA double strand breaks and chromosomal breaks were intact in Ku80-deficient cells surviving X-irradiation, whereas there was no sign for the production of chromosome bridges between divided daughter cells. Moreover, delayed induction of dicentric chromosomes was significantly compromised in those cells compared to the wild-type CHO cells. Reintroduction of the human Ku86 gene complimented the defective DNA repair and recovered delayed induction of dicentric chromosomes and delayed cell death, indicating that defective Ku80-dependent dicentric induction was the cause of the absence of delayed cell death. Since DNA-PKcs-defective cells showed delayed phenotypes, Ku80-dependent illegitimate rejoining is involved in delayed impairment of the integrity of the genome in radiation-survived cells.

  9. Survival Assessment of Mouse Preimplantation Embryos After Exposure to Cell Phone Radiation

    Science.gov (United States)

    Safian, Fereshteh; Khalili, Mohammad Ali; Khoradmehr, Arezoo; Anbari, Fatemeh; Soltani, Saeedeh; Halvaei, Iman

    2016-01-01

    Background: Using cellular phone has rapidly increased all over the world. Also, the concern on the possible health hazards of electromagnetic fields (EMF) induced from cell phones to reproduction has been growing in many countries. The aim of this study was to assess the consequences and effects of exposure to the cell phone radiation on the quality and survival rates of preimplantation embryos in mice. Methods: A total of 40 mice (20 females and 20 males), 6 weeks old and sexually mature BALB/c, were used for control and experimental groups. The ovary burses were removed and the zygotes were dissected in the morning after mating. Next, 2-cell embryos were divided into two groups of control (n=150) and experimental (n=150). EMF (900–1800 MHz) was used for four days in experimental group for 30 min/day in culture at 37°C in a CO 2 incubator. The quality of embryos was recorded daily and the fluorescent staining was used for identification of viable blastocysts. All data were compared by Student’s t-test and Mann-Whitney test (p<0.05). Results: The rate of embryo survival to the blastocysts stage was similar in both groups. However, the percentage of dead embryos at the 2-cell stage was significantly higher in EMF-exposed group compared with controls (p=0.03). Also, the loss of cell viability significantly increased in experimental blastocysts (p=0.002). Conclusion: The normal embryonic development up to the blastocyst stage indicates that EMF-exposure commonly did not have adverse effect on embryo development in mice. But, it caused loss of blastocysts cell viability. PMID:27478766

  10. NanOx, a new model to predict cell survival in the context of particle therapy

    Science.gov (United States)

    Cunha, M.; Monini, C.; Testa, E.; Beuve, M.

    2017-02-01

    Particle therapy is increasingly attractive for the treatment of tumors and the number of facilities offering it is rising worldwide. Due to the well-known enhanced effectiveness of ions, it is of utmost importance to plan treatments with great care to ensure tumor killing and healthy tissues sparing. Hence, the accurate quantification of the relative biological effectiveness (RBE) of ions, used in the calculation of the biological dose, is critical. Nevertheless, the RBE is a complex function of many parameters and its determination requires modeling. The approaches currently used have allowed particle therapy to thrive, but still show some shortcomings. We present herein a short description of a new theoretical framework, NanOx, to calculate cell survival in the context of particle therapy. It gathers principles from existing approaches, while addressing some of their weaknesses. NanOx is a multiscale model that takes the stochastic nature of radiation at nanometric and micrometric scales fully into account, integrating also the chemical aspects of radiation-matter interaction. The latter are included in the model by means of a chemical specific energy, determined from the production of reactive chemical species induced by irradiation. Such a production represents the accumulation of oxidative stress and sublethal damage in the cell, potentially generating non-local lethal events in NanOx. The complementary local lethal events occur in a very localized region and can, alone, lead to cell death. Both these classes of events contribute to cell death. The comparison between experimental data and model predictions for the V79 cell line show a good agreement. In particular, the dependence of the typical shoulders of cell survival curves on linear energy transfer are well described, but also the effectiveness of different ions, including the overkill effect. These results required the adjustment of a number of parameters compatible with the application of the model in

  11. Evidence that high-migration drug-surviving MOLT4 leukemia cells exhibit cancer stem cell-like properties.

    Science.gov (United States)

    Huang, Xiaoxing; Xiong, Meng; Jin, Yujie; Deng, Chaohua; Xu, Hui; An, Changqing; Hao, Ling; Yang, Xiangyong; Deng, Xinzhou; Tu, Zhenbo; Li, Xinran; Xiao, Ruijing; Zhang, Qiuping

    2016-07-01

    Leukemia represents a spectrum of hematological malignancies threatening human health. Resistance to treatments and metastasis of leukemia are the main causes of death in patients. Leukemia stem cells (LSCs) are the initiating cells of leukemia as well as the main source of drug resistance, invasion and metastasis. Consequently, eliminating LSCs is a prerequisite to eradicate leukemia. Preliminary studies in our laboratory have shown that chemokines and their related receptors play an important role in the drug resistance and metastasis of leukemic cells. In this study, we obtained high migration drug-surviving (short term) MOLT4 cells (hMDSCs-MOLT4) with treatment of doxorubicin (DOX) after Transwell assay. Then we detected stem cell-associated molecular markers on hMDSCs-MOLT4 cells and the parental MOLT4 cells by FCM, QPCR, western blotting, H&E staining and immunohisto-chemistry experimental techniques in vitro and in vivo. Moreover, we explored its impact on drug resistance and tumor formation. Then we found that compared with the parental MOLT4 cells, the mRNA expression levels of stem cell-related factors Sox2, Oct4, C-myc, Klf4, Nanog, Bmi-1, CXCR4 are increased in hMDSCs-MOLT4 cells, together with the protein expression levels of Sox2, Oct4, Klf4, Nanog, CXCR4 and CD34. Our results indicated that hMDSCs-MOLT4 cells exhibited strong drug resistance and certain cancer stem cell-like characteristics. It is the first indication that the targeting stemness factors such as Sox2, Oct4, Klf4, Nanog and CXCR4 may represent plausible options for eliminating T-ALL stem-like cells. The present findings shed light on the relationship between drug-tolerant leukemic cells and cancer stem cells.

  12. Bicaudal is a conserved substrate for Drosophila and mammalian caspases and is essential for cell survival.

    LENUS (Irish Health Repository)

    Creagh, Emma M

    2009-01-01

    Members of the caspase family of cysteine proteases coordinate cell death through restricted proteolysis of diverse protein substrates and play a conserved role in apoptosis from nematodes to man. However, while numerous substrates for the mammalian cell death-associated caspases have now been described, few caspase substrates have been identified in other organisms. Here, we have utilized a proteomics-based approach to identify proteins that are cleaved by caspases during apoptosis in Drosophila D-Mel2 cells, a subline of the Schneider S2 cell line. This approach identified multiple novel substrates for the fly caspases and revealed that bicaudal\\/betaNAC is a conserved substrate for Drosophila and mammalian caspases. RNAi-mediated silencing of bicaudal expression in Drosophila D-Mel2 cells resulted in a block to proliferation, followed by spontaneous apoptosis. Similarly, silencing of expression of the mammalian bicaudal homologue, betaNAC, in HeLa, HEK293T, MCF-7 and MRC5 cells also resulted in spontaneous apoptosis. These data suggest that bicaudal\\/betaNAC is essential for cell survival and is a conserved target of caspases from flies to man.

  13. Bicaudal is a conserved substrate for Drosophila and mammalian caspases and is essential for cell survival.

    Directory of Open Access Journals (Sweden)

    Emma M Creagh

    Full Text Available Members of the caspase family of cysteine proteases coordinate cell death through restricted proteolysis of diverse protein substrates and play a conserved role in apoptosis from nematodes to man. However, while numerous substrates for the mammalian cell death-associated caspases have now been described, few caspase substrates have been identified in other organisms. Here, we have utilized a proteomics-based approach to identify proteins that are cleaved by caspases during apoptosis in Drosophila D-Mel2 cells, a subline of the Schneider S2 cell line. This approach identified multiple novel substrates for the fly caspases and revealed that bicaudal/betaNAC is a conserved substrate for Drosophila and mammalian caspases. RNAi-mediated silencing of bicaudal expression in Drosophila D-Mel2 cells resulted in a block to proliferation, followed by spontaneous apoptosis. Similarly, silencing of expression of the mammalian bicaudal homologue, betaNAC, in HeLa, HEK293T, MCF-7 and MRC5 cells also resulted in spontaneous apoptosis. These data suggest that bicaudal/betaNAC is essential for cell survival and is a conserved target of caspases from flies to man.

  14. Suppression of Glioma-Cell Survival by Antisense and Dominant-Negative AKT2 RNA

    Institute of Scientific and Technical Information of China (English)

    Peiyu Pu; Chunsheng Kang; Jie Li; Guangxiu Wang

    2005-01-01

    OBJECTIVE Overexpression of growth factors and their receptors such as PDGF, FGF, VEGF, IGF, EGF, TGFα etc. Play a critical role in the development and progression of malignant gliomas. AKT, one of the most potent downstream signaling effectors of these growth factor receptors is usually overactivated in malignant gliomas. The present study was undertaken to investigate the effects of antisense and dominant negative AKT2 RNA on the survival of glioma cells with overexpression of AKT2.METHODS Antisense and dominant negative AKT2 constructs (AS-AKT2,DN-AKT2) were transfected into human glioblastoma cell line TJ905 with overexpression of AKT2. Using Western blotting, MTT assay, Ki67 labeling index (Ki67 LI), flow cytometry and the TUNEL method, the expression of AKT2 and GFAP, the proliferation rate and apoptosis of glioma cells transfected with AS-AKT2 or DN-AKT2 were compared to those characteristics of parental and glioma cells transfected with an empty vector.RESULTS Cell proliferation was inhibited in glioma cells transfected with ASAKT2 and DN-AKT2 RNA, while GFAP expression and apoptosis were markedly increased in those cells.CONCLUSION AKT is an important mediator in the growth signaling pathway of malignant gliomas and is a potential promising therapeutic target for malignant gliomas.

  15. Telomere dysfunction and cell survival: Roles for distinct TIN2-containing complexes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sahn-ho; Davalos, Albert R.; Heo, Seok-Jin; Rodier, Francis; Zou, Ying; Beausejour, Christian; Kaminker, Patrick; Yannone, Steven M.; Campisi, Judith

    2007-10-02

    Telomeres are maintained by three DNA binding proteins (TRF1, TRF2 and POT1), and several associated factors. One factor, TIN2, binds TRF1 and TRF2 directly and POT1 indirectly. Along with two other proteins, TPP1 and hRap1, these form a soluble complex that may be the core telomere maintenance complex. It is not clear whether sub-complexes also exist in vivo. We provide evidence for two TIN2 sub-complexes with distinct functions in human cells. We isolated these two TIN2 sub-complexes from nuclear lysates of unperturbed cells and cells expressing TIN2 mutants TIN2-13, TIN2-15C, which cannot bind TRF2 or TRF1, respectively. In cells with wild-type p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere uncapping and eventual growth arrest. In cells lacking p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere dysfunction and cell death. Our findings suggest that distinct TIN2 complexes exist, and that TIN2-15C-sensitive subcomplexes are particularly important for cell survival in the absence of functional p53.

  16. N-acetylcysteine impairs survival of luteal cells through mitochondrial dysfunction.

    Science.gov (United States)

    Löhrke, Berthold; Xu, Jinxian; Weitzel, Joachim M; Krüger, Burkhard; Goldammer, Tom; Viergutz, Torsten

    2010-04-01

    N-acetylcysteine (NAC) is known as an antioxidant and used for mucus viscosity reduction. However, this drug prevents or induces cell death depending on the cell type. The response of steroidogenic luteal cells to NAC is unknown. Our data shows that NAC can behave as an antioxidant or prooxidant in dependency on the concentration and mitochondrial energization. NAC elevated the flowcytometric-measured portion of hypodiploid (dying) cells. This rise was completely abolished by aurintricarboxylic acid, an inhibitor of topoisomerase II. NAC increased the secretion of nitric oxide and cellular nitrotyrosine. An image analysis indicated that cells pretreated with NAC and loaded with DHR showed a fluorescent structure probably elicited by the oxidative product of DHR, rhodamine 123 that sequesters mitochondrially. Pretreating luteal cells with NAC or adding NAC directly to mitochondrial fractions followed by assessing the mitochondrial transmembrane potential difference (Deltapsi) by the JC-1 technique demonstrated a marked decrease in Deltapsi. A protonophore restored Deltapsi and rotenone (an inhibitor of respiratory chain complex I) inhibited mitochondrial recovering. Thus, in steroidogenic luteal cells from healthy mature corpus luteum, NAC impairs cellular survival by interfering with mitochondrial metabolism. The protonophore-induced recovering of NAC-provoked decrease in Deltapsi indicates that an ATP synthase-favored route of H(+) re-entry to the matrix is essentially switched off by NAC while other respiratory chain complexes remain intact. These data may be important for therapeutic timing of treatments with NAC. (c) 2010 International Society for Advancement of Cytometry.

  17. MANF Is Indispensable for the Proliferation and Survival of Pancreatic β Cells

    Directory of Open Access Journals (Sweden)

    Maria Lindahl

    2014-04-01

    Full Text Available All forms of diabetes mellitus (DM are characterized by the loss of functional pancreatic β cell mass, leading to insufficient insulin secretion. Thus, identification of novel approaches to protect and restore β cells is essential for the development of DM therapies. Mesencephalic astrocyte-derived neurotrophic factor (MANF is an endoplasmic reticulum (ER-stress-inducible protein, but its physiological role in mammals has remained obscure. We generated MANF-deficient mice that strikingly develop severe diabetes due to progressive postnatal reduction of β cell mass, caused by decreased proliferation and increased apoptosis. Additionally, we show that lack of MANF in vivo in mouse leads to chronic unfolded protein response (UPR activation in pancreatic islets. Importantly, MANF protein enhanced β cell proliferation in vitro and overexpression of MANF in the pancreas of diabetic mice enhanced β cell regeneration. We demonstrate that MANF specifically promotes β cell proliferation and survival, thereby constituting a therapeutic candidate for β cell protection and regeneration.

  18. Identification of cytoskeleton-associated proteins essential for lysosomal stability and survival of human cancer cells

    DEFF Research Database (Denmark)

    Groth-Pedersen, Line; Aits, Sonja; Corcelle-Termeau, Elisabeth

    2012-01-01

    Microtubule-disturbing drugs inhibit lysosomal trafficking and induce lysosomal membrane permeabilization followed by cathepsin-dependent cell death. To identify specific trafficking-related proteins that control cell survival and lysosomal stability, we screened a molecular motor siRNA library...... in human MCF7 breast cancer cells. SiRNAs targeting four kinesins (KIF11/Eg5, KIF20A, KIF21A, KIF25), myosin 1G (MYO1G), myosin heavy chain 1 (MYH1) and tropomyosin 2 (TPM2) were identified as effective inducers of non-apoptotic cell death. The cell death induced by KIF11, KIF21A, KIF25, MYH1 or TPM2 si......), increased dextran accumulation (KIF20A), or reduced autophagic flux (MYO1G, MYH1). Importantly, all seven siRNAs also killed human cervix cancer (HeLa) and osteosarcoma (U-2-OS) cells and sensitized cancer cells to other lysosome-destabilizing treatments, i.e. photo-oxidation, siramesine, etoposide...

  19. Paracrine Effects of Bone Marrow Mononuclear Cells in Survival and Cytokine Expression after 90% Partial Hepatectomy

    Directory of Open Access Journals (Sweden)

    Carlos Oscar Kieling

    2017-01-01

    Full Text Available Acute liver failure is a complex and fatal disease. Cell-based therapies are a promising alternative therapeutic approach for liver failure due to relatively simple technique and lower cost. The use of semipermeable microcapsules has become an interesting tool for evaluating paracrine effects in vivo. In this study, we aimed to assess the paracrine effects of bone marrow mononuclear cells (BMMC encapsulated in sodium alginate to treat acute liver failure in an animal model of 90% partial hepatectomy (90% PH. Encapsulated BMMC were able to increase 10-day survival without enhancing liver regeneration markers. Gene expression of Il-6 and Il-10 in the remnant liver was markedly reduced at 6 h after 90% PH in animals receiving encapsulated BMMC compared to controls. This difference, however, was neither reflected by changes in the number of CD68+ cells nor by serum levels of IL6. On the other hand, treated animals presented increased caspase activity and gene expression in the liver. Taken together, these results suggest that BMMC regulate immune response and promote apoptosis in the liver after 90% PH by paracrine factors. These changes ultimately may be related to the higher survival observed in treated animals, suggesting that BMMC may be a promising alternative to treat acute liver failure.

  20. Unbiased and automated identification of a circulating tumour cell definition that associates with overall survival.

    Directory of Open Access Journals (Sweden)

    Sjoerd T Ligthart

    Full Text Available Circulating tumour cells (CTC in patients with metastatic carcinomas are associated with poor survival and can be used to guide therapy. Classification of CTC however remains subjective, as they are morphologically heterogeneous. We acquired digital images, using the CellSearch™ system, from blood of 185 castration resistant prostate cancer (CRPC patients and 68 healthy subjects to define CTC by computer algorithms. Patient survival data was used as the training parameter for the computer to define CTC. The computer-generated CTC definition was validated on a separate CRPC dataset comprising 100 patients. The optimal definition of the computer defined CTC (aCTC was stricter as compared to the manual CellSearch CTC (mCTC definition and as a consequence aCTC were less frequent. The computer-generated CTC definition resulted in hazard ratios (HRs of 2.8 for baseline and 3.9 for follow-up samples, which is comparable to the mCTC definition (baseline HR 2.9, follow-up HR 4.5. Validation resulted in HRs at baseline/follow-up of 3.9/5.4 for computer and 4.8/5.8 for manual definitions. In conclusion, we have defined and validated CTC by clinical outcome using a perfectly reproducing automated algorithm.

  1. Effects of gram-positive microorganisms and their products on in vivo survival of hemopoietic clonogenic cells.

    Science.gov (United States)

    Proskuryakov, S Ya; Konoplyannikov, A G; Konoplyannikova, O A; Tsyb, A F; Logunov, D Yu; Naroditsky, B S; Gintsburg, A L

    2008-04-01

    The effects of gram-positive bacterial strains (Lactobacillus acidophilus and Lactobacillus rhamnosus) and their subcellular components on the survival of hemopoietic clonogenic cells were evaluated by the formation of endogenous splenic colonies. The effects of these preparations on NO production were studied by the spin-trap paramagnetic resonance spectroscopy. Bacterial preparations from gram-positive bacteria stimulated survival of hemopoietic clonogenic cells, but did not induce NO production in contrast to E. coli LPS.

  2. Resistance of Foxp3+ regulatory T cells to Nur77-induced apoptosis promotes allograft survival.

    Directory of Open Access Journals (Sweden)

    Ran Tao

    Full Text Available The NR4A nuclear receptor family member Nur77 (NR4A1 promotes thymocyte apoptosis during negative selection of autoreactive thymocytes, but may also function in mature extrathymic T cells. We studied the effects of over-expression of Nur77 on the apoptosis of murine peripheral T cells, including thymic-derived Foxp3+ regulatory (Treg cells. Overexpression of Nur77 in the T cell lineage decreased numbers of peripheral CD4 and CD8 T cells by approximately 80% compared to wild-type (WT mice. However, the proportions of Treg cells were markedly increased in the thymus (61% of CD4+Foxp3+ singly positive thymocytes vs. 8% in WT and secondary lymphoid organs (40-50% of CD4+Foxp3+ T cells vs. 7-8% in WT of Nur77 transgenic (Nur77Tg mice, and immunoprecipitation studies showed Nur77 was associated with a recently identified HDAC7/Foxp3 transcriptional complex. Upon activation through the T cell receptor in vitro or in vivo, Nur77Tg T cells showed only marginally decreased proliferation but significantly increased apoptosis. Fully allogeneic cardiac grafts transplanted to Nur77Tg mice survived long-term with well-preserved structure, and recipient splenocytes showed markedly enhanced apoptosis and greatly reduced anti-donor recall responses. Allografts in Nur77Tg recipients had significantly increased expression of multiple Treg-associated genes, including Foxp3, Foxp1, Tip60 and HDAC9. Allograft rejection was restored by CD25 monoclonal antibody therapy, indicating that allograft acceptance was dependent upon Treg function in Nur77Tg recipients. These data show that compared to conventional CD4 and CD8 T cells, Foxp3+ Tregs are relatively resistant to Nur77-mediated apoptosis, and that tipping the balance between the numbers of Tregs and responder T cells in the early period post-transplantation can determine the fate of the allograft. Hence, induced expression of Nur77 might be a novel means to achieve long-term allograft survival.

  3. The phosphatase of regenerating liver-3 (PRL-3) is important for IL-6-mediated survival of myeloma cells.

    Science.gov (United States)

    Slørdahl, Tobias S; Abdollahi, Pegah; Vandsemb, Esten N; Rampa, Christoph; Misund, Kristine; Baranowska, Katarzyna A; Westhrin, Marita; Waage, Anders; Rø, Torstein B; Børset, Magne

    2016-05-10

    Multiple myeloma (MM) is a neoplastic proliferation of bone marrow plasma cells. PRL-3 is a phosphatase induced by interleukin (IL)-6 and other growth factors in MM cells and promotes MM-cell migration. PRL-3 has also been identified as a marker gene for a subgroup of patients with MM. In this study we found that forced expression of PRL-3 in the MM cell line INA-6 led to increased survival of cells that were depleted of IL-6. It also caused redistribution of cells in cell cycle, with an increased number of cells in G2M-phase. Furthermore, forced PRL-3 expression significantly increased phosphorylation of Signal transducer and activator of transcription (STAT) 3 both in the presence and the absence of IL-6. Knockdown of PRL-3 with shRNA reduced survival in MM cell line INA-6. A pharmacological inhibitor of PRL-3 reduced survival in the MM cell lines INA-6, ANBL-6, IH-1, OH-2 and RPMI8226. The inhibitor also reduced survival in 9 of 9 consecutive samples of purified primary myeloma cells. Treatment with the inhibitor down-regulated the anti-apoptotic protein Mcl-1 and led to activation of the intrinsic apoptotic pathway. Inhibition of PRL-3 also reduced IL-6-induced phosphorylation of STAT3. In conclusion, our study shows that PRL-3 is an important mediator of growth factor signaling in MM cells and hence possibly a good target for treatment of MM.

  4. Arctigenin protects against neuronal hearing loss by promoting neural stem cell survival and differentiation.

    Science.gov (United States)

    Huang, Xinghua; Chen, Mo; Ding, Yan; Wang, Qin

    2016-12-27

    Neuronal hearing loss has become a prevalent health problem. This study focused on the function of arctigenin (ARC) in promoting survival and neuronal differentiation of mouse cochlear neural stem cells (NSCs), and its protection against gentamicin (GMC) induced neuronal hearing loss. Mouse cochlea was used to isolate NSCs, which were subsequently cultured in vitro. The effects of ARC on NSC survival, neurosphere formation, differentiation of NSCs, neurite outgrowth, and neural excitability in neuronal network in vitro were examined. Mechanotransduction ability demonstrated by intact cochlea, auditory brainstem response (ABR), and distortion product optoacoustic emissions (DPOAE) amplitude in mice were measured to evaluate effects of ARC on GMC-induced neuronal hearing loss. ARC increased survival, neurosphere formation, neuron differentiation of NSCs in mouse cochlear in vitro. ARC also promoted the outgrowth of neurites, as well as neural excitability of the NSC-differentiated neuron culture. Additionally, ARC rescued mechanotransduction capacity, restored the threshold shifts of ABR and DPOAE in our GMC ototoxicity murine model. This study supports the potential therapeutic role of ARC in promoting both NSCs proliferation and differentiation in vitro to functional neurons, thus supporting its protective function in the therapeutic treatment of neuropathic hearing loss in vivo.

  5. Tumour thrombus consistency has no impact on survival in patients with renal cell carcinoma.

    Science.gov (United States)

    Gołąbek, T; Przydacz, M; Okoń, K; Kopczyński, J; Bukowczan, J; Sobczyński, R; Curyło, Ł; Gołąbek, K; Curyło, Ł; Chłosta, P

    2016-06-01

    The prognosis of renal cell carcinoma (RCC) with venous tumour thrombus (VTT) is variable and not always possible to predict. The prognostic impact and independence of tumour thrombus-related factors including the recently introduced tumour thrombus consistency (TTC) on overall survival remain controversial. The aim of this study was to investigate the prognostic role of TTC in patients' survival. We determined the tumour thrombus consistency (solid vs. friable) in a cohort of 84 patients with RCC and VTT who underwent nephrectomy with thrombectomy, and performed a retrospective evaluation of the patients' data from the prospectively maintained database. A total of 45% of patients had solid thrombus (sTT) and 55% had friable thrombus (fTT). The venous tumour thrombus consistency was not predictive of overall survival. Further studies, preferably prospective and with a larger number of patients, are needed to validate the obtained results, as well as to evaluate the usefulness of tumour thrombus consistency in clinical practice for stratifying the risk of recurrence and planning further follow-up.

  6. Leishmania Donovani Cell Surface Sialoglycans Regulate Susceptibility for Siglec Mediated Macrophage Invasion and Parasite Survival

    Directory of Open Access Journals (Sweden)

    Tripti De

    2012-02-01

    Full Text Available Glycoconjugates play a pivotal role in the survival of Leishmania parasites in destructive surroundings. An important constituent present on many glycoconjugates is sialic acid. By virtue of their peripheral position on oligosaccharide chains of glycoconjugates, sialic acids are well suited as molecular determinants of specific biological processes, including the interaction of pathogenic microorganisms with sialylated cellular receptors. Differences in a2,3- and a2,6-sialoglycan patterns detected in clonal virulent Leishmania donovani promastigotes, correlated with the level of a2,3- and a2,6-sialyltransferase activity present in these parasites. The role of macrophage sialic acid-receptors in uptake and survival of L.donovani was studied in the murine macrophage cell line raw 264.7. Macrophage invasion was dependent on the binding to Siglec-1, while suppression of MAPK signaling was mediated through Siglec-5. Sialic acid removal by neuraminidase treatment reduced parasite infectivity. The presence of trypsin resistant sialic acid residues in the neuraminidase treated parasites grown in a serum free medium in presence of sialoglycoconjugates indicated that the parasites could salvage sialic acid from exogenous sialoglycans and reutilize it for de novo glycoprotein sialylation in L.donovani parasites. Thus, our results demonstrate the involvement of sialoglycans in the invasion as well as the survival process of L.donovani parasites.

  7. Rapamycin Prolongs Cardiac Allograft Survival in a Mouse Model by Inducing Myeloid-Derived Suppressor Cells.

    Science.gov (United States)

    Nakamura, T; Nakao, T; Yoshimura, N; Ashihara, E

    2015-09-01

    Mammalian target of rapamycin (mTOR) inhibitors are the main immunosuppressive drugs for organ transplant recipients. Nevertheless, the mechanisms by which mTOR inhibitors induce immunosuppression is not fully understood. Myeloid-derived suppressor cells (MDSCs) maintain host immunity; however, the relationship between mTOR inhibitors and MDSCs is unclear. Here, the results from a murine cardiac transplantation model revealed that rapamycin treatment (3 mg/kg, intraperitoneally on postoperative days 0, 2, 4, and 6) led to the recruitment of MDSCs and increased their expression of inducible nitric oxide synthase (iNOS). Immunohistochemical analysis revealed that rapamycin induced the migration of iNOS-expressing MDSCs into the subintimal space within the allograft vessels, resulting in a significant prolongation of graft survival compared with that in the untreated group (67 days vs. 7 days, respectively). These effects were counterbalanced by the administration of an anti-Gr-1, which reduced allograft survival to 21 days. Moreover, adoptive transcoronary arterial transfer of MDSCs from rapamycin-treated recipients prolonged allograft survival; this increase was reversed by the anti-Gr-1 antibody. Finally, co-administration of rapamycin and a mitogen-activated protein kinase kinase (MEK) inhibitor trametinib reversed rapamycin-mediated MDSC recruitment. Thus, the mTOR and Raf/MEK/extracellular signal regulated kinase (ERK) signaling pathways appear to play an important role in MDSC expansion.

  8. Recurrence rates and survival in a Danish cohort with renal cell carcinoma

    DEFF Research Database (Denmark)

    Azawi, Nessn H; Tesfalem, Helen; Mosholt, Karina Sif Søndergaard;

    2016-01-01

    INTRODUCTION: Patients with localised and locally advanced renal cancer experience about 20% recurrence during a five-year follow-up period. The aim of the present study was to report recurrence rates and survival in a Danish population with renal cancer. METHODS: Data on patients diagnosed...... with renal cell carcinoma (RCC) at our institute from January 2005 to December 2013 were collected retrospectively. RESULTS: Overall, 367 patients were diagnosed with RCC during the period, and 78 patients (21%) presented with metastasis. The mean follow-up period for all patients was 41 months (standard...

  9. Salvianolic acid B promotes survival of transplanted mesenchymal stem cells in spinal cord-injured rats

    Institute of Scientific and Technical Information of China (English)

    Xiao-bin BI; Yu-bin DENG; Dan-hui GAN; Ya-zhu WANG

    2008-01-01

    Aim: Stem cells hold great promise for brain and spinal cord injuries (SCI), but cell survival following transplantation to adult central nervous system has been poor. Salvianolic acid B (Sal B) has been shown to improve functional recovery in brain-injured rats. The present study was designed to determine whether Sal B could improve transplanted mesenchymal stem cell (MSC) survival in SCI rats. Methods: SCI rats were treated with Sal B. The Basso-Beatie-Bresnahan (BBB) scale was used to test the functional recovery. Sal B was used to protect MSC from being damaged by TNF-α in vitro. Bromodeoxyuridine-labeled MSC were transplanted into SCI rats with Sal B intraperitoneal injection, simul-taneously. MSC were examined, and the functional recovery of the SCI rats was tested. Results: Sal B treatment significantly reduced the lesion area from 0.26±0.05 mm2 to 0.15±0.03 mm2 (P<0.01) and remarkably raised the BBB scores on d 28, post-injury, from 7.3±0.9 to 10.5±1.3 (P<0.05), compared with the phosphate-buffered saline (PBS) control group. MSC were protected from the damage of TNF-α by Sal B. The number of surviving MSC in the MSC plus Sal B groups were 1143.3± 195.6 and 764.0±81.3 on d 7 and 28, post-transplantation, more than those in the MSC group, which was 569.3±72.3 and 237.0±61.3, respectively (P<0.05). Rats with MSC trans-planted and Sal B injected obtained higher BBB scores than those with MSC transplanted alone (P<0.05) and PBS (P<0.01). Conclusion: Sal B provides neuroprotection to SCI and promotes the survival of MSC in vitro and after cell transplantation to the injured spinal cord in vivo.

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

    DEFF Research Database (Denmark)

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

    1997-01-01

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

  11. JAM-C maintains VEGR2 expression to promote retinal pigment epithelium cell survival under oxidative stress.

    Science.gov (United States)

    Jia, Xin; Zhao, Chen; Chen, Qishan; Du, Yuxiang; Huang, Lijuan; Ye, Zhimin; Ren, Xiangrong; Wang, Shasha; Lee, Chunsik; Tang, Zhongshu; Li, Xuri; Ju, Rong

    2017-04-03

    Junctional adhesion molecule-C (JAM-C) has been shown to play critical roles during development and in immune responses. However, its role in adult eyes under oxidative stress remains poorly understood. Here, we report that JAM-C is abundantly expressed in adult mouse retinae and choroids in vivo and in cultured retinal pigment epithelium (RPE) and photoreceptor cells in vitro. Importantly, both JAM-C expression and its membrane localisation are downregulated by H2O2-induced oxidative stress. Under H2O2-induced oxidative stress, JAM-C is critically required for the survival of human RPE cells. Indeed, loss of JAM-C by siRNA knockdown decreased RPE cell survival. Mechanistically, we show that JAM-C is required to maintain VEGFR2 expression in RPE cells, and VEGFR2 plays an important role in keeping the RPE cells viable since overexpression of VEGFR2 partially restored impaired RPE survival caused by JAM-C knockdown and increased RPE survival. We further show that JAM-C regulates VEGFR2 expression and, in turn, modulates p38 phosphorylation. Together, our data demonstrate that JAM-C plays an important role in maintaining VEGR2 expression to promote RPE cell survival under oxidative stress. Given the vital importance of RPE in the eye, approaches that can modulate JAM-C expression may have therapeutic values in treating diseases with impaired RPE survival.

  12. BAP31 and its caspase cleavage product regulate cell surface expression of tetraspanins and integrin-mediated cell survival.

    Science.gov (United States)

    Stojanovic, Marina; Germain, Marc; Nguyen, Mai; Shore, Gordon C

    2005-08-26

    BAP31, a resident integral protein of the endoplasmic reticulum membrane, regulates the export of other integral membrane proteins to the downstream secretory pathway. Here we show that cell surface expression of the tetraspanins CD9 and CD81 is compromised in mouse cells from which the Bap31 gene has been deleted. CD9 and CD81 facilitate the function of multiprotein complexes at the plasma membrane, including integrins. Of note, BAP31 does not appear to influence the egress of alpha5beta1 or alpha(v)beta3 integrins to the cell surface, but in Bap31-null mouse cells, these integrins are not able to maintain cellular adhesion to the extracellular matrix in the presence of reduced serum. Consequently, Bap31-null cells are sensitive to serum starvation-induced apoptosis. Reconstitution of wild-type BAP31 into these Bap31-null cells restores integrin-mediated cell attachment and cell survival after serum stress, whereas interference with the functions of CD9, alpha5beta1, or alpha(v)beta3 by antagonizing antibodies makes BAP31 cells act similar to Bap31-null cells in these respects. Finally, in human KB epithelial cells protected from apoptosis by BCL-2, the caspase-8 cleavage product, p20 BAP31, inhibits egress of tetraspanin and integrin-mediated cell attachment. Thus, p20 BAP31 can operate upstream of BCL-2 in living cells to influence cell surface properties due to its effects on protein egress from the endoplasmic reticulum.

  13. Propolis augments apoptosis induced by butyrate via targeting cell survival pathways.

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    Eric Drago

    Full Text Available Diet is one of the major lifestyle factors affecting incidence of colorectal cancer (CC, and despite accumulating evidence that numerous diet-derived compounds modulate CC incidence, definitive dietary recommendations are not available. We propose a strategy that could facilitate the design of dietary supplements with CC-preventive properties. Thus, nutrient combinations that are a source of apoptosis-inducers and inhibitors of compensatory cell proliferation pathways (e.g., AKT signaling may produce high levels of programmed death in CC cells. Here we report the combined effect of butyrate, an apoptosis inducer that is produced through fermentation of fiber in the colon, and propolis, a honeybee product, on CC cells. We established that propolis increases the apoptosis of CC cells exposed to butyrate through suppression of cell survival pathways such as the AKT signaling. The programmed death of CC cells by combined exposure to butyrate and propolis is further augmented by inhibition of the JNK signaling pathway. Analyses on the contribution of the downstream targets of JNK signaling, c-JUN and JAK/STAT, to the apoptosis of butyrate/propolis-treated CC cells ascertained that JAK/STAT signaling has an anti-apoptotic role; whereas, the role of cJUN might be dependent upon regulatory cell factors. Thus, our studies ascertained that propolis augments apoptosis of butyrate-sensitive CC cells and re-sensitizes butyrate-resistant CC cells to apoptosis by suppressing AKT signaling and downregulating the JAK/STAT pathway. Future in vivo studies should evaluate the CC-preventive potential of a dietary supplement that produces high levels of colonic butyrate, propolis, and diet-derived JAK/STAT inhibitors.

  14. Protecting and rescuing the effectors: roles of differentiation and survival in the control of memory T cell development

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    Sema eKurtulus

    2013-01-01

    Full Text Available Vaccines, arguably the single most important intervention in improving human health, have exploited the phenomenon of immunological memory. The elicitation of memory T cells is often an essential part of successful long-lived protective immunity. Our understanding of T cell memory has been greatly aided by the development of TCR Tg mice and MHC tetrameric staining reagents that have allowed the precise tracking of antigen-specific T cell responses. Indeed, following acute infection or immunization, naïve T cells undergo a massive expansion culminating in the generation of a robust effector T cell population. This peak effector response is relatively short-lived and, while most effector T cells die by apoptosis, some remain and develop into memory cells. Although the molecular mechanisms underlying this cell fate decision remain incompletely defined, substantial progress has been made, particularly with regards to CD8+ T cells. For example, the effector CD8+ T cells generated during a response are heterogeneous, consisting of cells with more or less potential to develop into full-fledged memory cells. Development of CD8+ T cell memory is regulated by the transcriptional programs that control the differentiation and survival of effector T cells. While the type of antigenic stimulation and level of inflammation control effector CD8+ T cell differentiation, availability of cytokines and their ability to control expression and function of Bcl-2 family members governs their survival. These distinct differentiation and survival programs may allow for finer therapeutic intervention to control both the quality and quantity of CD8+ T cell memory. Effector to memory transition of CD4+ T cells is less well characterized than CD8+ T cells, emerging details will be discussed. This review will focus on the recent progress made in our understanding of the mechanisms underlying the development of T cell memory with an emphasis on factors controlling survival of

  15. Runx-dependent expression of PKC is critical for cell survival in the sea urchin embryo

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    McCarthy John J

    2005-08-01

    Full Text Available Abstract Background Runx transcription factors play critical roles in the developmental control of cell fate and contribute variously as oncoproteins and tumor suppressors to leukemia and other cancers. To discover fundamental Runx functions in the cell biology of animal development, we have employed morpholino antisense-mediated knockdown of the sea urchin Runx protein SpRunt-1. Previously we showed that embryos depleted of SpRunt-1 arrest development at early gastrula stage and underexpress the conventional protein kinase C SpPKC1. Results We report here that SpRunt-1 deficiency leads to ectopic cell proliferation and extensive apoptosis. Suppression of the apoptosis by pharmacological inhibition of caspase-3 prevents the ectopic proliferation and rescues gastrulation, indicating that many of the overt defects obtained by knockdown of SpRunt-1 are secondary to the apoptosis. Inhibition or knockdown of SpPKC1 also causes apoptosis, while cell survival is rescued in SpRunt-1 morphant embryos coinjected with SpPKC1 mRNA, suggesting that the apoptosis associated with SpRunt-1 deficiency is caused by the deficit in SpPKC1 expression. Chromatin immunoprecipitation indicates that SpRunt-1 interacts physically with SpPKC1 in vivo, and cis-regulatory analysis shows that this interaction activates SpPKC1 transcription. Conclusions Our results show that Runx-dependent activation of SpPKC1 is essential for maintaining protein kinase C activity at levels conducive to cell survival during embryogenesis.

  16. Latent KSHV Infected Endothelial Cells Are Glutamine Addicted and Require Glutaminolysis for Survival.

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    Erica L Sanchez

    2015-07-01

    Full Text Available Kaposi's Sarcoma-associated Herpesvirus (KSHV is the etiologic agent of Kaposi's Sarcoma (KS. KSHV establishes a predominantly latent infection in the main KS tumor cell type, the spindle cell, which is of endothelial cell origin. KSHV requires the induction of multiple metabolic pathways, including glycolysis and fatty acid synthesis, for the survival of latently infected endothelial cells. Here we demonstrate that latent KSHV infection leads to increased levels of intracellular glutamine and enhanced glutamine uptake. Depletion of glutamine from the culture media leads to a significant increase in apoptotic cell death in latently infected endothelial cells, but not in their mock-infected counterparts. In cancer cells, glutamine is often required for glutaminolysis to provide intermediates for the tri-carboxylic acid (TCA cycle and support for the production of biosynthetic and bioenergetic precursors. In the absence of glutamine, the TCA cycle intermediates alpha-ketoglutarate (αKG and pyruvate prevent the death of latently infected cells. Targeted drug inhibition of glutaminolysis also induces increased cell death in latently infected cells. KSHV infection of endothelial cells induces protein expression of the glutamine transporter, SLC1A5. Chemical inhibition of SLC1A5, or knockdown by siRNA, leads to similar cell death rates as glutamine deprivation and, similarly, can be rescued by αKG. KSHV also induces expression of the heterodimeric transcription factors c-Myc-Max and related heterodimer MondoA-Mlx. Knockdown of MondoA inhibits expression of both Mlx and SLC1A5 and induces a significant increase in cell death of only cells latently infected with KSHV, again, fully rescued by the supplementation of αKG. Therefore, during latent infection of endothelial cells, KSHV activates and requires the Myc/MondoA-network to upregulate the glutamine transporter, SLC1A5, leading to increased glutamine uptake for glutaminolysis. These findings

  17. The anaphase-promoting complex or cyclosome supports cell survival in response to endoplasmic reticulum stress.

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    Meifan Chen

    Full Text Available The anaphase-promoting complex or cyclosome (APC/C is a multi-subunit ubiquitin ligase that regulates exit from mitosis and G1 phase of the cell cycle. Although the regulation and function of APC/C(Cdh1 in the unperturbed cell cycle is well studied, little is known of its role in non-genotoxic stress responses. Here, we demonstrate the role of APC/C(Cdh1 (APC/C activated by Cdh1 protein in cellular protection from endoplasmic reticulum (ER stress. Activation of APC/C(Cdh1 under ER stress conditions is evidenced by Cdh1-dependent degradation of its substrates. Importantly, the activity of APC/C(Cdh1 maintains the ER stress checkpoint, as depletion of Cdh1 by RNAi impairs cell cycle arrest and accelerates cell death following ER stress. Our findings identify APC/C(Cdh1 as a regulator of cell cycle checkpoint and cell survival in response to proteotoxic insults.

  18. Cancer cells that survive checkpoint adaptation contain micronuclei that harbor damaged DNA.

    Science.gov (United States)

    Lewis, Cody W; Golsteyn, Roy M

    2016-11-16

    We have examined the relationship between checkpoint adaptation (mitosis with damaged DNA) and micronuclei. Micronuclei in cancer cells are linked to genomic change, and may induce chromothripsis (chromosome shattering). We measured the cytotoxicity of the cancer drug cisplatin in M059K (glioma fibroblasts, IC50 15 μM). Nearly 100% of M059K cells were positive for histone γH2AX staining after 48 h treatment with a cytotoxic concentration of cisplatin. The proportion of micronucleated cells, as confirmed by microscopy using DAPI and lamin A/C staining, increased from 24% to 48%, and the total micronuclei in surviving cells accumulated over time. Promoting entry into mitosis with a checkpoint inhibitor increased the number of micronuclei in cells whereas blocking checkpoint adaptation with a Cdk inhibitor reduced the number of micronuclei. Interestingly, some micronuclei underwent asynchronous DNA replication, relative to the main nuclei, as measured by deoxy-bromo-uracil (BrdU) staining. These micronuclei stained positive for histone γH2AX, which was linked to DNA replication, suggesting that micronuclei arise from checkpoint adaptation and that micronuclei may continue to damage DNA. By contrast the normal cell line WI-38 did not undergo checkpoint adaptation when treated with cisplatin and did not show changes in micronuclei number. These data reveal that the production of micronuclei by checkpoint adaptation is part of a process that contributes to genomic change.

  19. The lens controls cell survival in the retina: Evidence from the blind cavefish Astyanax.

    Science.gov (United States)

    Strickler, Allen G; Yamamoto, Yoshiyuki; Jeffery, William R

    2007-11-15

    The lens influences retinal growth and differentiation during vertebrate eye development but the mechanisms are not understood. The role of the lens in retinal growth and development was studied in the teleost Astyanax mexicanus, which has eyed surface-dwelling (surface fish) and blind cave-dwelling (cavefish) forms. A lens and laminated retina initially develop in cavefish embryos, but the lens dies by apoptosis. The cavefish retina is subsequently disorganized, apoptotic cells appear, the photoreceptor layer degenerates, and retinal growth is arrested. We show here by PCNA, BrdU, and TUNEL labeling that cell proliferation continues in the adult cavefish retina but the newly born cells are removed by apoptosis. Surface fish to cavefish lens transplantation, which restores retinal growth and rod cell differentiation, abolished apoptosis in the retina but not in the RPE. Surface fish lens deletion did not cause apoptosis in the surface fish retina or affect RPE differentiation. Neither lens transplantation in cavefish nor lens deletion in surface fish affected retinal cell proliferation. We conclude that the lens acts in concert with another optic component, possibly the RPE, to promote retinal cell survival. Accordingly, deficiency in both optic structures may lead to eye degeneration in cavefish.

  20. Cited3 activates Mef2c to control muscle cell differentiation and survival.

    Science.gov (United States)

    Devakanmalai, Gnanapackiam Sheela; Zumrut, Hasan E; Ozbudak, Ertuğrul M

    2013-05-15

    Vertebrate muscle development occurs through sequential differentiation of cells residing in somitic mesoderm - a process that is largely governed by transcriptional regulators. Our recent spatiotemporal microarray study in zebrafish has identified functionally uncharacterized transcriptional regulators that are expressed at the initial stages of myogenesis. cited3 is one such novel gene encoding a transcriptional coactivator, which is expressed in the precursors of oxidative slow-twitch myofibers. Our experiments placed cited3 into a gene regulatory network, where it acts downstream of Hedgehog signaling and myoD/myf5 but upstream of mef2c. Knockdown of expression of cited3 by antisense morpholino oligonucleotides impaired muscle cell differentiation and growth, caused muscle cell death and eventually led to total immotility. Transplantation experiments demonstrated that Cited3 cell-autonomously activates the expression of mef2c in slow myofibers, while it non-cell-autonomously regulates expression of structural genes in fast myofibers. Restoring expression of cited3 or mef2c rescued all the cited3 loss-of-function phenotypes. Protein truncation experiments revealed the functional necessity of C-terminally conserved domain of Cited3, which is known to mediate interactions of Cited-family proteins with histone acetylases. Our findings demonstrate that Cited3 is a critical transcriptional coactivator functioning during muscle differentiation and its absence leads to defects in terminal differentiation and survival of muscle cells.

  1. Survival motor neuron protein regulates stem cell division, proliferation, and differentiation in Drosophila.

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    Stuart J Grice

    2011-04-01

    Full Text Available Spinal muscular atrophy is a severe neurogenic disease that is caused by mutations in the human survival motor neuron 1 (SMN1 gene. SMN protein is required for the assembly of small nuclear ribonucleoproteins and a dramatic reduction of the protein leads to cell death. It is currently unknown how the reduction of this ubiquitously essential protein can lead to tissue-specific abnormalities. In addition, it is still not known whether the disease is caused by developmental or degenerative defects. Using the Drosophila system, we show that SMN is enriched in postembryonic neuroblasts and forms a concentration gradient in the differentiating progeny. In addition to the developing Drosophila larval CNS, Drosophila larval and adult testes have a striking SMN gradient. When SMN is reduced in postembryonic neuroblasts using MARCM clonal analysis, cell proliferation and clone formation defects occur. These SMN mutant neuroblasts fail to correctly localise Miranda and have reduced levels of snRNAs. When SMN is removed, germline stem cells are lost more frequently. We also show that changes in SMN levels can disrupt the correct timing of cell differentiation. We conclude that highly regulated SMN levels are essential to drive timely cell proliferation and cell differentiation.

  2. Differential Adaptive Response and Survival of Salmonella enterica Serovar Enteritidis Planktonic and Biofilm Cells Exposed to Benzalkonium Chloride▿

    Science.gov (United States)

    Mangalappalli-Illathu, Anil K.; Vidović, Sinisa; Korber, Darren R.

    2008-01-01

    This study examined the adaptive response and survival of planktonic and biofilm phenotypes of Salmonella enterica serovar Enteritidis adapted to benzalkonium chloride (BC). Planktonic cells and biofilms were continuously exposed to 1 μg ml−1 of BC for 144 h. The proportion of BC-adapted biofilm cells able to survive a lethal BC treatment (30 μg ml−1) was significantly higher (4.6-fold) than that of BC-adapted planktonic cells. Similarly, there were 18.3-fold more survivors among the BC-adapted biofilm cells than among their nonadapted (i.e., without prior BC exposure) cell counterparts at the lethal BC concentration, and this value was significantly higher than the value for BC-adapted planktonic cells versus nonadapted cells (3.2-fold). A significantly higher (P < 0.05) proportion of surviving cells was noticed among BC-adapted biofilm cells relative to BC-adapted planktonic cells following a 10-min heat shock at 55°C. Fatty acid composition was significantly influenced by phenotype (planktonic cells or biofilm) and BC adaptation. Cell surface roughness of biofilm cells was also significantly greater (P < 0.05) than that of planktonic cells. Key proteins upregulated in BC-adapted planktonic and biofilm cells included CspA, TrxA, Tsf, YjgF, and a probable peroxidase, STY0440. Nine and 17 unique proteins were upregulated in BC-adapted planktonic and biofilm cells, respectively. These results suggest that enhanced biofilm-specific upregulation of 17 unique proteins, along with the increased expression of CspA, TrxA, Tsf, YjgF, and a probable peroxidase, phenotype-specific alterations in cell surface roughness, and a shift in fatty acid composition conferred enhanced survival to the BC-adapted biofilm cell population relative to their BC-adapted planktonic cell counterparts. PMID:18663028

  3. NGF is an essential survival factor for bronchial epithelial cells during respiratory syncytial virus infection.

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    Sreekumar Othumpangat

    Full Text Available Overall expression of neurotrophins in the respiratory tract is upregulated in infants infected by the respiratory syncytial virus (RSV, but it is unclear where (structural vs. inflammatory cells, upper vs. lower airways and why, these changes occur. We analyzed systematically the expression of neurotrophic factors and receptors following RSV infection of human nasal, tracheal, and bronchial epithelial cells, and tested the hypothesis that neurotrophins work as innate survival factors for infected respiratory epithelia.Expression of neurotrophic factors (nerve growth factor, NGF; brain-derived neurotrophic factor, BDNF and receptors (trkA, trkB, p75 was analyzed at the protein level by immunofluorescence and flow cytometry and at the mRNA level by real-time PCR. Targeted siRNA was utilized to blunt NGF expression, and its effect on virus-induced apoptosis/necrosis was evaluated by flow cytometry following annexin V/7-AAD staining.RSV infection was more efficient in cells from more distal (bronchial vs. more proximal origin. In bronchial cells, RSV infection induced transcript and protein overexpression of NGF and its high-affinity receptor trkA, with concomitant downregulation of the low-affinity p75(NTR. In contrast, tracheal cells exhibited an increase in BDNF, trkA and trkB, and nasal cells increased only trkA. RSV-infected bronchial cells transfected with NGF-specific siRNA exhibited decreased trkA and increased p75(NTR expression. Furthermore, the survival of bronchial epithelial cells was dramatically decreased when their endogenous NGF supply was depleted prior to RSV infection.RSV infection of the distal airway epithelium, but not of the more proximal sections, results in overexpression of NGF and its trkA receptor, while the other p75(NTR receptor is markedly downregulated. This pattern of neurotrophin expression confers protection against virus-induced apoptosis, and its inhibition amplifies programmed cell death in the infected

  4. Dendritic Cell Based Vaccines that Utilize Myeloid Rather than Plasmacytoid Cells Offer a Superior Survival Advantage in Malignant Glioma

    Science.gov (United States)

    Dey, Mahua; Chang, Alan L.; Miska, Jason; Wainwright, Derek A.; Ahmed, Atique U.; Balyasnikova, Irina V.; Pytel, Peter; Han, Yu; Tobias, Alex; Zhang, Lingjiao; Qiao, Jian; Lesniak, Maciej S.

    2015-01-01

    Dendritic cells (DC) are professional antigen presenting cells (APC) that are traditionally divided into two distinct subsets: myeloid DC (mDCs) and plasmacytoid DC (pDCs). pDCs are known for their ability to secrete large amount of IFN-α. Apart from IFN-α production, pDCs can also process antigen and induce T-cell immunity or tolerance. In several solid tumors, pDCs have been shown to play a critical role in promoting tumor immunosuppression. We investigated the role of pDCs in the process of glioma progression in the syngeneic murine model of glioma. We show that glioma-infiltrating pDCs are the major APC in glioma and are deficient in IFN-α secretion (p < 0.05). pDC depletion leads to increased survival of the mice bearing intracranial tumor by decreasing the number of regulatory T-cells (Treg) and by decreasing the suppressive capabilities of Tregs. We subsequently compared the ability of mDCs and pDCs to generate effective anti-glioma immunity in a GL261-OVA mouse model of glioma. Our data suggest that mature pDCs and mDCs isolated from naïve mice can be effectively activated and loaded with SIINFEKL antigen in vitro. Upon intra-dermal injection in the hind leg, a fraction of both types of DCs migrate to the brain and lymph nodes.. Compared to mice vaccinated with pDC or control mice, mice vaccinated with mDCs generated a robust Th1 type immune response, characterized by high frequency of CD4+Tbet+ T-cells and CD8+Siinfekel+ T-cells. This robust anti-tumor T-cell response resulted in tumor eradication and long-term survival in 60% of the animals (p<0.001). PMID:26026061

  5. Effects of Ionizing Radiation and Glutathione Precursor on Antioxidant Enzyme and Cell Survival in Yeast

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jinkyu; Roh, Changhyun; Ryu, Taeho; Park, Jiyoung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Nili, Michael A. [Oxiage Cosmeceutical Research Institute, Virginia (United States)

    2013-05-15

    Cells react to such an induced oxidative stress through scavenging the generated reactive oxygen species to reduce oxidative damage. Antioxidant enzymes such as glutathione peroxidase, catalase, and superoxide dismutase are immediately triggered for reactive oxygen species. N-acetyl-L-cysteine (NAC), a precursor of glutathione, is one of the antioxidants. The effect of NAC as an antioxidant and/or a cell rescue agent was investigated in the present study. Glutathione (GSH) is the most abundant intracellular thiol, which involves in antioxidant defense via direct interaction with ROS or via activities of detoxication enzymes like glutathione peroxidases (GPx). NAC flowed in the cell is converted to cysteine by deacetylation, that is supplied to the depleted GSH by oxidative stress. NAC prevents the depletion of GSH by radiation, increases the production of GSH, and improves enzymes activity such as GPx and alkaline phosphatase. Cell growth and survivorship and transcriptional level of glutathione gene are analyzed in two yeast strains exposed to combined treatment of NAC with gamma-rays. The effect of NAC on cell growth was measured during 72 hours. The cell growth was hampered by higher concentrations of NAC at stationary phase. NAC, however, didn't affect the cell division at the exponential phase. The survival of the cells decreased with radiation dose. The cell viability of the strain W303-1A was reduced significantly at the low dose (10 and 30 Gy). By comparison, the strain W303-1A was more sensitive to radiation with having a half lethal dose (LD{sub 50}) of about 20 Gy. The quantitative RT-PCR analysis showed that the transcriptional expression of antioxidant enzyme gene GPX1 increased after irradiation while the expression of the gene decreased by the combined treatment of NAC with 100 Gy radiation. The present study shows that NAC can directly scavenge ROS against oxidative stress in vivo. In conclusion, NAC can prevent radiation-induced oxidative

  6. Survival and SOS response induction in ultraviolet B irradiated Escherichia coli cells with defective repair mechanisms.

    Science.gov (United States)

    Prada Medina, Cesar Augusto; Aristizabal Tessmer, Elke Tatjana; Quintero Ruiz, Nathalia; Serment-Guerrero, Jorge; Fuentes, Jorge Luis

    2016-06-01

    Purpose In this paper, the contribution of different genes involved in DNA repair for both survival and SOS induction in Escherichia coli mutants exposed to ultraviolet B radiation (UVB, [wavelength range 280-315 nm]) was evaluated. Materials and methods E. coli strains defective in uvrA, oxyR, recO, recN, recJ, exoX, recB, recD or xonA genes were used to determine cell survival. All strains also had the genetic sulA::lacZ fusion, which allowed for the quantification of SOS induction through the SOS Chromotest. Results Five gene products were particularly important for survival, as follows: UvrA > RecB > RecO > RecJ > XonA. Strains defective in uvrA and recJ genes showed elevated SOS induction compared with the wild type, which remained stable for up to 240 min after UVB-irradiation. In addition, E. coli strains carrying the recO or recN mutation showed no SOS induction. Conclusions The nucleotide excision and DNA recombination pathways were equally used to repair UVB-induced DNA damage in E. coli cells. The sulA gene was not turned off in strains defective in UvrA and RecJ. RecO protein was essential for processing DNA damage prior to SOS induction. In this study, the roles of DNA repair proteins and their contributions to the mechanisms that induce SOS genes in E. coli are proposed.

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

    Science.gov (United States)

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

    2014-03-01

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

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

    Directory of Open Access Journals (Sweden)

    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

  9. Possible involvement of NO in the stimulating effect of pifithrins on survival of hemopoietic clonogenic cells.

    Science.gov (United States)

    Proskuryakov, S Ya; Konoplyannikov, A G; Konoplyannikova, O A; Shevchenko, L I; Verkhovskii, Yu G; Tsyb, A F

    2009-02-01

    Pifithrin alpha (PFTalpha), one of the first known low molecular weight modulators of activity of tumor suppressor p53, increases survival of hemopoietic clonogenic cells (evaluated by the criterion of formation of endogenous spleen CFU-C8 colonies in irradiated animals). This effect appeared when PFTalpha was administered either before or after irradiation. Increase in CFU-C8 was also observed after administration of two PFTalpha analogs, derivatives of 2-amino-4,5,6,7-tetrahydrobenzothiazole. These included a parent compound, 2-ATBT (2-amino-4,5,6,7-tetrahydrobenzothiazole), which is used for synthesis of PFTalpha, and a product of its intramolecular cyclization under physiological conditions, cyclo-PFT (2-(4-methylphenyl)imidazo[2,1-b]-5,6,7,8-tetrahydrobenzothiazole). Earlier we found that many low molecular weight compounds increasing number of CFU-C8 (e.g. isothiourea derivatives) demonstrate NO inhibitory activity. Such activity was also found in 2-ATBT and cyclo-PFT by means of EPR spectroscopy of NO. These compounds caused more than twofold inhibition of NO production in vivo. Thus, it has been demonstrated that PFTalpha and its structural analogs increase survival of hemopoietic clonogenic cells in vivo, and NO may play a role in the mechanism of this effect.

  10. Assessment of the Radioprotection Efficacy of Antioxidant Substances in Foods in regard to Clonogenic Cell Survival

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyosung; Lee, Minho; Kim, Eunhee [Seoul National Univ., Seoul (Korea, Republic of)

    2014-05-15

    Radiation is perceived as a hazard in spite of its diverse uses. The public are more sensitive than ever to the activities from the nuclear power plant industry since Fukushima accident and the consequential environment contamination. The never-dissolved fear from the public of the nuclear energy costs the nuclear industry too much for safety measures not to mention brings the public uneasy life. Beta carotene, oltipraz and luteolin, which are easily taken from various foods, are substances that may protect cells from damage caused by unstable molecules known as free radicals. The purpose of this study is to inform people of accessible radiation protection measures in everyday lives. Three antioxidant substances were investigated regarding their radioprotection effects counted in terms of clonogenic cell surviving fraction in vitro. The radioprotection efficacy was observed with those substances at concentrations below certain levels. At concentrations beyond those levels, the efficacy was canceled out by their inherent cytotoxicity.

  11. The survival of cultured mouse cerebellar granule cells is not dependent on elevated potassium-ion concentration

    DEFF Research Database (Denmark)

    Mogensen, Helle Smidt; Hack, N; Balázs, R

    1994-01-01

    The effects of K(+)-induced membrane depolarization were studied on the survival and biochemical parameters in mouse and rat cerebellar granule cells grown in micro-well cultures. Cell numbers were determined by estimating DNA content using the Hoechst 33258 fluorochrome binding assay. DNA from d...... that although cultivation in 'high' K+ promotes biochemical differentiation in mouse cerebellar granule cells, these cells differ from their rat counterparts in that they do not develop a survival requirement for K(+)-induced membrane depolarization.......The effects of K(+)-induced membrane depolarization were studied on the survival and biochemical parameters in mouse and rat cerebellar granule cells grown in micro-well cultures. Cell numbers were determined by estimating DNA content using the Hoechst 33258 fluorochrome binding assay. DNA from...... degenerated cells was removed by prior DNAase treatment. These DNA estimates of cell numbers were comparable with values obtained by direct counting of fluorescein diacetate-stained viable cells. In agreement with previous studies, the survival of rat granule cells was promoted by increasing the concentration...

  12. Low concentrations of nitric oxide delay the differentiation of embryonic stem cells and promote their survival.

    Science.gov (United States)

    Tejedo, J R; Tapia-Limonchi, R; Mora-Castilla, S; Cahuana, G M; Hmadcha, A; Martin, F; Bedoya, F J; Soria, B

    2010-10-07

    Nitric oxide (NO) is an intracellular messenger in several cell systems, but its contribution to embryonic stem cell (ESC) biology has not been characterized. Exposure of ESCs to low concentrations (2-20 μM) of the NO donor diethylenetriamine NO adduct confers protection from apoptosis elicited by leukaemia inhibitory factor (LIF) withdrawal. NO blocked caspase 3 activation, PARP degradation, downregulation of the pro-apoptotic genes Casp7, Casp9, Bax and Bak1 and upregulation of the anti-apoptotic genes Bcl-2 111, Bcl-2 and Birc6. These effects were also observed in cells overexpressing eNOS. Exposure of LIF-deprived mESCs to low NO prevented the loss of expression of self-renewal genes (Oct4, Nanog and Sox2) and the SSEA marker. Moreover, NO blocked the differentiation process promoted by the absence of LIF and bFGF in mouse and human ESCs. NO treatment decreased the expression of differentiation markers, such as Brachyury, Gata6 and Gata4. Constitutive overexpression of eNOS in cells exposed to LIF deprivation maintained the expression of self-renewal markers, whereas the differentiation genes were repressed. These effects were reversed by addition of the NOS inhibitor L-NMMA. Altogether, the data suggest that low NO has a role in the regulation of ESC differentiation by delaying the entry into differentiation, arresting the loss of self-renewal markers and promoting cell survival by inhibiting apoptosis.

  13. Low concentrations of nitric oxide delay the differentiation of embryonic stem cells and promote their survival

    Science.gov (United States)

    Tejedo, J R; Tapia-Limonchi, R; Mora-Castilla, S; Cahuana, G M; Hmadcha, A; Martin, F; Bedoya, F J; Soria, B

    2010-01-01

    Nitric oxide (NO) is an intracellular messenger in several cell systems, but its contribution to embryonic stem cell (ESC) biology has not been characterized. Exposure of ESCs to low concentrations (2–20 μM) of the NO donor diethylenetriamine NO adduct confers protection from apoptosis elicited by leukaemia inhibitory factor (LIF) withdrawal. NO blocked caspase 3 activation, PARP degradation, downregulation of the pro-apoptotic genes Casp7, Casp9, Bax and Bak1 and upregulation of the anti-apoptotic genes Bcl-2 111, Bcl-2 and Birc6. These effects were also observed in cells overexpressing eNOS. Exposure of LIF-deprived mESCs to low NO prevented the loss of expression of self-renewal genes (Oct4, Nanog and Sox2) and the SSEA marker. Moreover, NO blocked the differentiation process promoted by the absence of LIF and bFGF in mouse and human ESCs. NO treatment decreased the expression of differentiation markers, such as Brachyury, Gata6 and Gata4. Constitutive overexpression of eNOS in cells exposed to LIF deprivation maintained the expression of self-renewal markers, whereas the differentiation genes were repressed. These effects were reversed by addition of the NOS inhibitor L-NMMA. Altogether, the data suggest that low NO has a role in the regulation of ESC differentiation by delaying the entry into differentiation, arresting the loss of self-renewal markers and promoting cell survival by inhibiting apoptosis. PMID:21368853

  14. Survival, proliferation, and migration of human meningioma stem-like cells in a nanopeptide scaffold

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    Sajad Sahab Negah

    2016-12-01

    Full Text Available Objective(s: In order to grow cells in a three-dimensional (3D microenvironment, self-assembling peptides, such as PuraMatrix, have emerged with potential to mimic the extracellular matrix. The aim of the present study was to investigate the influence of the self-assembling peptide on the morphology, survival, proliferation rate, migration potential, and differentiation of human meningioma stem-like cells (hMgSCs. Materials and Methods: The efficacy of a novel method for placing hMgSCs in PuraMatrix (the injection approach was compared to the encapsulation and surface plating methods. In addition, we designed a new method for measurement of migration distance in 3D cultivation of hMgSCs in PuraMatrix. Results: Our results revealed that hMgSCs have the ability to form spheres in stem cell culture condition. These meningioma cells expressed GFAP, CD133, vimentin, and nestin. Using the injection method, a higher proliferation rate of the hMgSCs was observed after seven days of culture. Furthermore, the novel migration assay was able to measure the migration of a single cell alone in 3D environment. Conclusion: The results indicate the injection method as an efficient technique for culturing hMgSCs in PuraMatrix. Furthermore, the novel migration assay enables us to evaluate the migration of hMgSCs.

  15. An essential role for DNA methyltransferase DNMT3B in cancer cell survival.

    Science.gov (United States)

    Beaulieu, Normand; Morin, Steves; Chute, Ian C; Robert, Marie-France; Nguyen, Hannah; MacLeod, A Robert

    2002-08-02

    Abnormal methylation and associated silencing of tumor suppressor genes is a common feature of many types of cancers. The observation of persistent methylation in human cancer cells lacking the maintenance methyltransferase DNMT1 suggests the involvement of other DNA methyltransferases in gene silencing in cancer. To test this hypothesis, we have evaluated methylation and gene expression in cancer cells specifically depleted of DNMT3A or DNMT3B, de novo methyltransferases that are expressed in adult tissues. Here we have shown that depletion of DNMT3B, but not DNMT3A, induced apoptosis of human cancer cells but not normal cells. DNMT3B depletion reactivated methylation-silenced gene expression but did not induce global or juxtacentromeric satellite demethylation as did specific depletion of DNMT1. Furthermore, the effect of DNMT3B depletion was rescued by exogenous expression of either of the splice variants DNMT3B2 or DNMT3B3 but not DNMT1. These results indicate that DNMT3B has significant site selectivity that is distinct from DNMT1, regulates aberrant gene silencing, and is essential for cancer cell survival.

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

    Science.gov (United States)

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

    2014-03-01

    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.

  17. Smad2 and Smad6 as predictors of overall survival in oral squamous cell carcinoma patients

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    Snitcovsky Igor

    2010-05-01

    Full Text Available Abstract Background To test if the expression of Smad1-8 mRNAs were predictive of survival in patients with oral squamous cell carcinoma (SCC. Patients and Methods We analyzed, prospectively, the expression of Smad1-8, by means of Ribonuclease Protection Assay in 48 primary, operable, oral SCC. In addition, 21 larynx, 10 oropharynx and 4 hypopharynx SCC and 65 matched adjacent mucosa, available for study, were also included. For survival analysis, patients were categorized as positive or negative for each Smad, according to median mRNA expression. We also performed real-time quantitative PCR (QRTPCR to asses the pattern of TGFβ1, TGFβ2, TGFβ3 in oral SCC. Results Our results showed that Smad2 and Smad6 mRNA expression were both associated with survival in Oral SCC patients. Cox Multivariate analysis revealed that Smad6 positivity and Smad2 negativity were both predictive of good prognosis for oral SCC patients, independent of lymph nodal status (P = 0.003 and P = 0.029, respectively. In addition, simultaneously Smad2- and Smad6+ oral SCC group of patients did not reach median overall survival (mOS whereas the mOS of Smad2+/Smad6- subgroup was 11.6 months (P = 0.004, univariate analysis. Regarding to TGFβ isoforms, we found that Smad2 mRNA and TGFβ1 mRNA were inversely correlated (p = 0.05, R = -0.33, and that seven of the eight TGFβ1+ patients were Smad2-. In larynx SCC, Smad7- patients did not reach mOS whereas mOS of Smad7+ patients were only 7.0 months (P = 0.04. No other correlations were found among Smad expression, clinico-pathological characteristics and survival in oral, larynx, hypopharynx, oropharynx or the entire head and neck SCC population. Conclusion Smad6 together with Smad2 may be prognostic factors, independent of nodal status in oral SCC after curative resection. The underlying mechanism which involves aberrant TGFβ signaling should be better clarified in the future.

  18. Identification of cytoskeleton-associated proteins essential for lysosomal stability and survival of human cancer cells.

    Science.gov (United States)

    Groth-Pedersen, Line; Aits, Sonja; Corcelle-Termeau, Elisabeth; Petersen, Nikolaj H T; Nylandsted, Jesper; Jäättelä, Marja

    2012-01-01

    Microtubule-disturbing drugs inhibit lysosomal trafficking and induce lysosomal membrane permeabilization followed by cathepsin-dependent cell death. To identify specific trafficking-related proteins that control cell survival and lysosomal stability, we screened a molecular motor siRNA library in human MCF7 breast cancer cells. SiRNAs targeting four kinesins (KIF11/Eg5, KIF20A, KIF21A, KIF25), myosin 1G (MYO1G), myosin heavy chain 1 (MYH1) and tropomyosin 2 (TPM2) were identified as effective inducers of non-apoptotic cell death. The cell death induced by KIF11, KIF21A, KIF25, MYH1 or TPM2 siRNAs was preceded by lysosomal membrane permeabilization, and all identified siRNAs induced several changes in the endo-lysosomal compartment, i.e. increased lysosomal volume (KIF11, KIF20A, KIF25, MYO1G, MYH1), increased cysteine cathepsin activity (KIF20A, KIF25), altered lysosomal localization (KIF25, MYH1, TPM2), increased dextran accumulation (KIF20A), or reduced autophagic flux (MYO1G, MYH1). Importantly, all seven siRNAs also killed human cervix cancer (HeLa) and osteosarcoma (U-2-OS) cells and sensitized cancer cells to other lysosome-destabilizing treatments, i.e. photo-oxidation, siramesine, etoposide or cisplatin. Similarly to KIF11 siRNA, the KIF11 inhibitor monastrol induced lysosomal membrane permeabilization and sensitized several cancer cell lines to siramesine. While KIF11 inhibitors are under clinical development as mitotic blockers, our data reveal a new function for KIF11 in controlling lysosomal stability and introduce six other molecular motors as putative cancer drug targets.

  19. Dendritic Cell-Based Vaccines that Utilize Myeloid Rather than Plasmacytoid Cells Offer a Superior Survival Advantage in Malignant Glioma.

    Science.gov (United States)

    Dey, Mahua; Chang, Alan L; Miska, Jason; Wainwright, Derek A; Ahmed, Atique U; Balyasnikova, Irina V; Pytel, Peter; Han, Yu; Tobias, Alex; Zhang, Lingjiao; Qiao, Jian; Lesniak, Maciej S

    2015-07-01

    Dendritic cells (DCs) are professional APCs that are traditionally divided into two distinct subsets, myeloid DC (mDCs) and plasmacytoid DC (pDCs). pDCs are known for their ability to secrete large amounts of IFN-α. Apart from IFN-α production, pDCs can also process Ag and induce T cell immunity or tolerance. In several solid tumors, pDCs have been shown to play a critical role in promoting tumor immunosuppression. We investigated the role of pDCs in the process of glioma progression in the syngeneic murine model of glioma. We show that glioma-infiltrating pDCs are the major APC in glioma and are deficient in IFN-α secretion (p < 0.05). pDC depletion leads to increased survival of the mice bearing intracranial tumor by decreasing the number of regulatory T cells (Tregs) and by decreasing the suppressive capabilities of Tregs. We subsequently compared the ability of mDCs and pDCs to generate effective antiglioma immunity in a GL261-OVA mouse model of glioma. Our data suggest that mature pDCs and mDCs isolated from naive mice can be effectively activated and loaded with SIINFEKL Ag in vitro. Upon intradermal injection in the hindleg, a fraction of both types of DCs migrate to the brain and lymph nodes. Compared to mice vaccinated with pDC or control mice, mice vaccinated with mDCs generate a robust Th1 type immune response, characterized by high frequency of CD4(+)T-bet(+) T cells and CD8(+)SIINFEKEL(+) T cells. This robust antitumor T cell response results in tumor eradication and long-term survival in 60% of the animals (p < 0.001).

  20. Hydrogen sulfide mediates the anti-survival effect of sulforaphane on human prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Pei, Yanxi [Department of Biology, Lakehead University, Thunder Bay (Canada); College of Life Science, Shanxi University, Taiyuan (China); Wu, Bo [Department of Biology, Lakehead University, Thunder Bay (Canada); Department of Pathophysiology, Harbin Medical University, Harbin (China); Cao, Qiuhui [Department of Biology, Lakehead University, Thunder Bay (Canada); Wu, Lingyun [Department of Pathophysiology, Harbin Medical University, Harbin (China); Department of Pharmacology, University of Saskatchewan, Saskatoon (Canada); Yang, Guangdong, E-mail: gyang@lakeheadu.ca [The School of Kinesiology, Lakehead University, Thunder Bay (Canada)

    2011-12-15

    Hydrogen sulfide (H{sub 2}S) is a novel gasotransmitter that regulates cell proliferation and other cellular functions. Sulforaphane (SFN) is a sulfur-containing compound that exhibits anticancer properties, and young sprouts of broccoli are particularly rich in SFN. There is consistent epidemiological evidence that the consumption of sulfur-containing vegetables, such as garlic and cruciferous vegetables, may help reduce the occurrence of prostate cancer. Here we found that a large amount of H{sub 2}S is released when SFN is added into cell culture medium or mixed with mouse liver homogenates, respectively. Both SFN and NaHS (a H{sub 2}S donor) decreased the viability of PC-3 cells (a human prostate cancer cell line) in a dose-dependent manner, and supplement of methemoglobin or oxidized glutathione (two H{sub 2}S scavengers) reversed SFN-reduced cell viability. We further found both cystathionine gamma-lyase (CSE) and cystathionine beta-synthase are expressed in PC-3 cells and mouse prostate tissues. H{sub 2}S production in prostate tissues from CSE knockout mice was only 20% of that from wild-type mice, suggesting CSE is a major H{sub 2}S-producing enzyme in prostate. CSE overexpression enhanced H{sub 2}S production and inhibited cell viability in PC-3 cells. In addition, both SFN and NaHS activated p38 mitogen-activated protein kinases (MAPK) and c-Jun N-terminal kinase (JNK). Pre-treatment of PC-3 cells with methemoglobin decreased SFN-stimulated MAPK activities. Suppression of both p38 MAPK and JNK reversed H{sub 2}S- or SFN-reduced viability of PC-3 cells. Our results demonstrated that H{sub 2}S mediates the inhibitory effect of SFN on the proliferation of PC-3 cells, which suggests that H{sub 2}S-releasing diet or drug might be beneficial in the treatment of prostate cancer. Highlights: Black-Right-Pointing-Pointer A large amount of H{sub 2}S is released from sulforaphane. Black-Right-Pointing-Pointer H{sub 2}S mediates the anti-survival effect of

  1. Effect of alpha lipoic acid on retinal ganglion cell survival in an optic nerve crush model

    Science.gov (United States)

    Liu, Ruixing; Wang, Yanling; Pu, Mingliang

    2016-01-01

    Purpose This study was conducted to determine whether alpha lipoic acid (ALA) promotes the survival of retinal ganglion cells (RGCs) in a rat model of optic nerve crush (ONC) injury and to investigate the neuroprotective mechanisms of ALA in the retina in this ONC injury model. Methods Adult male Sprague-Dawley rats (180–220 g) were subjected to ONC injury surgery. ALA (63 mg/kg) was injected intravenously 1 day before or after the ONC injury. Animals were euthanized after 10 days, and the number of ganglion cells positive for RNA-binding protein with multiple splicing (Rbpms), which is an RGC marker, were counted on the whole mount retinas. In addition, immunofluorescence and immunoblotting were performed to examine the localization and levels of erythropoietin receptor (EPOR) and neurotrophin-4/5 (NT4/5) in the retinas in all experimental groups. To determine whether the EPO/EPOR signaling pathway was involved in the ALA antioxidant pathway, the rats were subjected to ruxolitinib (INCB018424, 0.25 mg/kg, bid, intraperitoneal, i.p.) treatment after the animals were injected intravenously with ALA 1 day before ONC injury. Results The average number of Rbpms-positive cells/mm2 in the control group (sham-operated group), the ONC group, the ALA-ONC group, and the ONC-ALA group retinas was 2219±28, 418±8, 848±22, and 613±18/mm2, respectively. The ALA-ONC and ONC-ALA groups showed a statistically significantly increased RGC survival rate compared to the ONC group. There were statistical differences in the RGC survival rates between the ALA-ONC (39%) and ONC-ALA groups (28%; p<0.05). Immunofluorescent labeling showed that EPOR and NT4/5 expression was significant in the retinal ganglion cell layer (GCL). At the same time, western blot analysis revealed that ALA induced upregulation of EPOR protein and NT4/5 protein expression in the retina after ONC injury. However, INCB018424 reversed the protective effects of ALA on the ONC retinas. Conclusions ALA has

  2. Protein kinase G1 α overexpression increases stem cell survival and cardiac function after myocardial infarction.

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    Linlin Wang

    Full Text Available BACKGROUND: We hypothesized that overexpression of cGMP-dependent protein kinase type 1α (PKG1α could mimic the effect of tadalafil on the survival of bone marrow derived mesenchymal stem cells (MSCs contributing to regeneration of the ischemic heart. METHODS AND RESULTS: MSCs from male rats were transduced with adenoviral vector encoding for PKG1α ((PKG1αMSCs.Controls included native MSCs ((NatMSCs and MSCs transduced with an empty vector ((NullMSCs. PKG1α activity was increased approximately 20, 5 and 16 fold respectively in (PKG1αMSCs. (PKG1αMSCs showed improved survival under oxygen and glucose deprivation (OGD which was evidenced by lower LDH release, caspase-3/7 activity and number of positive TUNEL cells. Anti-apoptotic proteins pAkt, pGSK3β, and Bcl-2 were significantly increased in (PKG1αMSCs compared to (NatMSCs and (NullMSCs. Higher release of multiple prosurvival and angiogenic factors such as HGF, bFGF, SDF-1 and Ang-1 was observed in (PKG1αMSCs before and after OGD. In a female rat model of acute myocardial infarction, (PKG1αMSCs group showed higher survival compared with (NullMSCs group at 3 and 7 days after transplantation as determined by TUNEL staining and sry-gene quantitation by real-time PCR. Increased anti-apoptotic proteins and paracrine factors in vitro were also identified. Immunostaining for cardiac troponin I combined with GFP showed increased myogenic differentiation of (PKG1αMSCs. At 4 weeks after transplantation, compared to DMEM group and (NullMSCs group, (PKG1αMSCs group showed increased blood vessel density in infarct and peri-infarct areas (62.5±7.7; 68.8±7.3 per microscopic view, p<0.05 and attenuated infarct size (27.2±2.5%, p<0.01. Heart function indices including ejection fraction (52.1±2.2%, p<0.01 and fractional shortening (24.8%±1.3%, p<0.01 were improved significantly in (PKG1αMSCs group. CONCLUSION: Overexpression of PKG1α transgene could be a powerful approach to improve MSCs

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

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    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.

  4. TGF-beta expression during rat pregnancy and activity on decidual cell survival

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    Déry Marie-Claude

    2005-05-01

    decidual endometrial stromal cells revealed that TGF-beta1 induced apoptosis and Smad2 phosphorylation. Moreover, TGF-beta1 reduced both Akt (a well known survival factor phosphorylation and XIAP (X-linked inhibitor of apoptosis protein expression in decidual endometrial stromal cells in vitro. Conclusion Taken together, these results suggest that TGF-beta isoforms are regulated differently during pregnancy and may have an important role in the control of apoptosis and cell survival at specific stages during pregnancy.

  5. Inflammatory cytokines regulate endothelial cell survival and tissue repair functions via NF-κB signaling

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    Kanaji N

    2011-09-01

    Full Text Available Nobuhiro Kanaji1, Tadashi Sato2, Amy Nelson3, Xingqi Wang3, YingJi Li4, Miok Kim5, Masanori Nakanishi6, Hesham Basma3, Joel Michalski3, Maha Farid3, Michael Chandler3, William Pease3, Amol Patil3, Stephen I Rennard3, Xiangde Liu31Division of Hematology, Rheumatology and Respiratory Medicine, Kagawa University, Kagawa, Japan; 2Department of Respiratory Medicine, Juntendo University School of Medicine, Tokyo, Japan; 3Pulmonary and Critical Care Medicine, University of Nebraska Medical Center, Omaha, Nebraska; 4Department of Hygiene and Public Health, Nippon Medical School, Tokyo, Japan; 5Third Department of Internal Medicine, Wakayama Medical University School of Medicine, Wakayama, Japan; 6Department of Internal Medicine, Jeju Medical College, Jeju, Republic of KoreaAbstract: Inflammation contributes to the development of fibrotic and malignant diseases. We assessed the ability of inflammatory cytokines to modulate endothelial cell survival and functions related to tissue repair/remodeling. Treatment with interleukin (IL-1ß or tumor necrosis factor (TNF-α (2 ng/mL led to human pulmonary artery endothelial cells becoming spindle-shaped fibroblast-like cells. However, immunoblot and DNA microarray showed no change in most endothelial and mesenchymal markers. In the presence of IL-1ß or TNF-α, cells were resistant to apoptosis induced by deprivation of serum and growth factor, and were more migratory. In addition, cells treated with IL-1ß or TNF-α contracted collagen gels more robustly. In contrast, transforming growth factor-ß1 did not induce these responses. RNA interference targeting nuclear factor (NF- κB p65 blocked the effects of IL-1ß or TNF-α on cell morphologic change, survival, migration, and collagen gel contraction. These results suggest that endothelial cells may contribute to tissue repair/remodeling via the NF-κB signaling in a milieu of airway inflammation.Keywords: NF-κB, IL-1ß, TNF-α, apoptosis, tissue repair

  6. Increased survival of normal cells during laser photodynamic therapy: implications for ex vivo autologous bone marrow purging

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    Gulliya, K.S.; Matthews, J.L.; Fay, J.W.; Dowben, R.M.

    1988-01-01

    Laser light-induced, dye-mediated photolysis of leukemic cells was tested in an in vitro model for its efficacy in eliminating occult tumor cells for ex vivo autologous bone marrow purging. Merocyanine 540 (MC540) was mixed with acute promyelocytic leukemia (HL-60) cells in the presence of human albumin. This cell-dye mixture was irradiated with 514 nm argon laser light. Results show that in the presence of 0.1%, 0.25% and 0.5% albumin, laser light doses of 62.4 J/cm/sup 2/, 93.6 J/cm/sup 2/ and 109.2 J/cm/sup 2/, respectively, were required for a 5 log reduction in the survival of leukemic cells. Under identical conditions, 80% to 84% of the normal bone marrow cells and 41% of the granulocyte-macrophage colony forming cells survived. The number of surviving stromal cells was reduced (1+) compared to the untreated control (4+). Mixing of irradiated bone marrow cells with equal number of HL-60 cells did not interfere with the killing of HL-60 cells treated with MC540 and laser light. The non-specific cytotoxicity of laser light alone was less than 6% for normal bone marrow cells. These results suggest that the concentration of human albumin plays an important role in laser light-induced phototoxicity. This laser light-induced selective photolysis of leukemic cells can be used in ex vivo purging of tumor cell-contaminated bone marrow grafts to achieve very high survival rates of normal bone marrow cells and granulocyte-macrophage colony forming cells.

  7. Midkine is a NF-κB-inducible gene that supports prostate cancer cell survival

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    You Zongbing

    2008-02-01

    Full Text Available Abstract Background Midkine is a heparin-binding growth factor that is over-expressed in various human cancers and plays important roles in cell transformation, growth, survival, migration, and angiogenesis. However, little is known about the upstream factors and signaling mechanisms that regulate midkine gene expression. Methods Two prostate cancer cell lines LNCaP and PC3 were studied for their expression of midkine. Induction of midkine expression in LNCaP cells by serum, growth factors and cytokines was determined by Western blot analysis and/or real-time quantitative reverse-transcription – polymerase chain reaction (RT-PCR. The cell viability was determined by the trypan blue exclusion assay when the LNCaP cells were treated with tumor necrosis factor alpha (TNFα and/or recombinant midkine. When the LNCaP cells were treated with recombinant midkine, activation of intracellular signalling pathways was determined by Western blot analysis. Prostate tissue microarray slides containing 129 cases (18 normal prostate tissues, 40 early stage cancers, and 71 late stage cancers were assessed for midkine expression by immunohistochemical staining. Results We identified that fetal bovine serum, some growth factors (epidermal growth factor, androgen, insulin-like growth factor-I, and hepatocyte growth factor and cytokines (TNFα and interleukin-1beta induced midkine expression in a human prostate cancer cell line LNCaP cells. TNFα also induced midkine expression in PC3 cells. TNFα was the strongest inducer of midkine expression via nuclear factor-kappa B pathway. Midkine partially inhibited TNFα-induced apoptosis in LNCaP cells. Knockdown of endogenous midkine expression by small interfering RNA enhanced TNFα-induced apoptosis in LNCaP cells. Midkine activated extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase pathways in LNCaP cells. Furthermore, midkine expression was significantly increased in late stage

  8. Differential effects in cells exposed to ultra-short, high intensity electric fields: cell survival, DNA damage, and cell cycle analysis.

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    Stacey, M; Stickley, J; Fox, P; Statler, V; Schoenbach, K; Beebe, S J; Buescher, S

    2003-12-09

    High power, nanosecond pulsed electric field (nsPEF) effects have been focused on bacterial decontamination, but the impact on mammalian cells is now being revealed. During nsPEF applications, electrical pulses of 10, 60 or 300 ns durations were applied to cells using electric field amplitudes as high as 300 kV/cm. Because of the ultra-short pulse durations, the energy transferred to cells is negligible, and only non-thermal effects are observed. We investigated the genotoxicity of nsPEF on adherent and non-adherent cell lines including 10 human lines and one mouse cell line with different origin and growth characteristics. We present data examining the effects of nsPEF exposure on cell survival assessed by clonogenic formation or live cell count; DNA damage determined by the comet assay and chromosome aberrations; and cell cycle parameters by measuring the mitotic indices of exposed cells. Using each of these indicators, we observed differential effects among cell types with non-adherent cells being more sensitive to the genotoxic effects of nsPEF exposures than adherent cells. Non-adherent cultures showed a rapid decrease in cell viability (90%), induction of DNA damage, and a decrease in the number of cells reaching mitosis after one 60 ns pulse with an electric field intensity of 60 kV/cm. These effects were not observed in cells grown as adherent cultures, with the exception of the mouse 3T3 cell line, which showed survival characteristics similar to non-adherent cultures. These data suggest that nsPEF genotoxicity may be cell type specific, and therefore have potential applications in the selective removal of one cell type from another, for example, in diseased states.

  9. TAM receptors support neural stem cell survival, proliferation and neuronal differentiation.

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    Rui Ji

    Full Text Available Tyro3, Axl and Mertk (TAM receptor tyrosine kinases play multiple functional roles by either providing intrinsic trophic support for cell growth or regulating the expression of target genes that are important in the homeostatic regulation of immune responses. TAM receptors have been shown to regulate adult hippocampal neurogenesis by negatively regulation of glial cell activation in central nervous system (CNS. In the present study, we further demonstrated that all three TAM receptors were expressed by cultured primary neural stem cells (NSCs and played a direct growth trophic role in NSCs proliferation, neuronal differentiation and survival. The cultured primary NSCs lacking TAM receptors exhibited slower growth, reduced proliferation and increased apoptosis as shown by decreased BrdU incorporation and increased TUNEL labeling, than those from the WT NSCs. In addition, the neuronal differentiation and maturation of the mutant NSCs were impeded, as characterized by less neuronal differentiation (β-tubulin III+ and neurite outgrowth than their WT counterparts. To elucidate the underlying mechanism that the TAM receptors play on the differentiating NSCs, we examined the expression profile of neurotrophins and their receptors by real-time qPCR on the total RNAs from hippocampus and primary NSCs; and found that the TKO NSC showed a significant reduction in the expression of both nerve growth factor (NGF and brain-derived neurotrophic factor (BDNF, but accompanied by compensational increases in the expression of the TrkA, TrkB, TrkC and p75 receptors. These results suggest that TAM receptors support NSCs survival, proliferation and differentiation by regulating expression of neurotrophins, especially the NGF.

  10. Phosphoinositide binding differentially regulates NHE1 Na+/H+ exchanger-dependent proximal tubule cell survival.

    Science.gov (United States)

    Abu Jawdeh, Bassam G; Khan, Shenaz; Deschênes, Isabelle; Hoshi, Malcolm; Goel, Monu; Lock, Jeffrey T; Shinlapawittayatorn, Krekwit; Babcock, Gerald; Lakhe-Reddy, Sujata; DeCaro, Garren; Yadav, Satya P; Mohan, Maradumane L; Naga Prasad, Sathyamangla V; Schilling, William P; Ficker, Eckhard; Schelling, Jeffrey R

    2011-12-01

    Tubular atrophy predicts chronic kidney disease progression, and is caused by proximal tubular epithelial cellcaused by proximal tubular epithelial cell (PTC) apoptosis. The normally quiescent Na(+)/H(+) exchanger-1 (NHE1) defends against PTC apoptosis, and is regulated by PI(4,5)P(2) binding. Because of the vast array of plasma membrane lipids, we hypothesized that NHE1-mediated cell survival is dynamically regulated by multiple anionic inner leaflet phospholipids. In membrane overlay and surface plasmon resonance assays, the NHE1 C terminus bound phospholipids with low affinity and according to valence (PIP(3) > PIP(2) > PIP = PA > PS). NHE1-phosphoinositide binding was enhanced by acidic pH, and abolished by NHE1 Arg/Lys to Ala mutations within two juxtamembrane domains, consistent with electrostatic interactions. PI(4,5)P(2)-incorporated vesicles were distributed to apical and lateral PTC domains, increased NHE1-regulated Na(+)/H(+) exchange, and blunted apoptosis, whereas NHE1 activity was decreased in cells enriched with PI(3,4,5)P(3), which localized to basolateral membranes. Divergent PI(4,5)P(2) and PI(3,4,5)P(3) effects on NHE1-dependent Na(+)/H(+) exchange and apoptosis were confirmed by selective phosphoinositide sequestration with pleckstrin homology domain-containing phospholipase Cδ and Akt peptides, PI 3-kinase, and Akt inhibition in wild-type and NHE1-null PTCs. The results reveal an on-off switch model, whereby NHE1 toggles between weak interactions with PI(4,5)P(2) and PI(3,4,5)P(3). In response to apoptotic stress, NHE1 is stimulated by PI(4,5)P(2), which leads to PI 3-kinase activation, and PI(4,5)P(2) phosphorylation. The resulting PI(3,4,5)P(3) dually stimulates sustained, downstream Akt survival signaling, and dampens NHE1 activity through competitive inhibition and depletion of PI(4,5)P(2).

  11. Survival and signaling changes in antigen presenting cell subsets after radiation

    Science.gov (United States)

    Parker, Jennifer Janell

    cell and APC subsets are dying by apoptosis after radiation, and that the differential level of Bax expression is an important determinant of the relative radiosensitivity of these immune cell subsets. Again, these findings are clinically relevant to transplant patients and patients with tumors receiving radiation therapy since APC survival may have importance for the generation of anti-tumor immunity and post-transplantation immune sequelae such as GVHD. In addition, elucidation of the mechanism of death of APC and T cell subsets, as described in chapter 3, provides potential markers of cell death that can be correlated to good graft versus tumor (GVT) effects versus bad (tumor recurrence and persistence) GVT effects. Thus, understanding the mechanistic basis for radiation-induced changes in APC and the effect of these changes on survival and function is essential for optimizing the use of radiation in transplantation and tumor vaccine treatment protocols.

  12. The Survival Strategies of Malaria Parasite in the Red Blood Cell and Host Cell Polymorphisms

    Directory of Open Access Journals (Sweden)

    Gunanidhi Dhangadamajhi

    2010-01-01

    Full Text Available Parasite growth within the erythrocyte causes dramatic alterations of host cell which on one hand facilitates nutrients acquisition from extracellular environment and on other hand contributes to the symptoms of severe malaria. The current paper focuses on interactions between the Plasmodium parasite and its metabolically highly reduced host cell, the natural selection of numerous polymorphisms in the genes encoding hemoglobin and other erythrocyte proteins.

  13. Necdin modulates proliferative cell survival of human cells in response to radiation-induced genotoxic stress

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    Lafontaine Julie

    2012-06-01

    Full Text Available Abstract Background The finite replicative lifespan of cells, termed cellular senescence, has been proposed as a protective mechanism against the proliferation of oncogenically damaged cells, that fuel cancer. This concept is further supported by the induction of premature senescence, a process which is activated when an oncogene is expressed in normal primary cells as well as following intense genotoxic stresses. Thus, deregulation of genes that control this process, like the tumor suppressor p53, may contribute to promoting cancer by allowing cells to bypass senescence. A better understanding of the genes that contribute to the establishment of senescence is therefore warranted. Necdin interacts with p53 and is also a p53 target gene, although the importance of Necdin in the p53 response is not clearly understood. Methods In this study, we first investigated Necdin protein expression during replicative senescence and premature senescence induced by gamma irradiation and by the overexpression of oncogenic RasV12. Gain and loss of function experiments were used to evaluate the contribution of Necdin during the senescence process. Results Necdin expression declined during replicative aging of IMR90 primary human fibroblasts or following induction of premature senescence. Decrease in Necdin expression seemed to be a consequence of the establishment of senescence since the depletion of Necdin in human cells did not induce a senescence-like growth arrest nor a flat morphology or SA-β-galactosidase activity normally associated with senescence. Similarly, overexpression of Necdin did not affect the life span of IMR90 cells. However, we demonstrate that in normal human cells, Necdin expression mimicked the effect of p53 inactivation by increasing radioresistance. Conclusion This result suggests that Necdin potentially attenuate p53 signaling in response to genotoxic stress in human cells and supports similar results describing an inhibitory function

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Immature CD4+ dendritic cells conditioned with donor kidney antigen prolong renal allograft survival in rats

    Institute of Scientific and Technical Information of China (English)

    WANG Tao; XU Lin; LI Heng; HUANG Zheng-yu; ZHANG Sheng-ping; MIAO Bin; NA Ning

    2012-01-01

    Background AIIogeneic transplant rejection is currently a major problem encountered during organ transplantation.The dendritic cell (DC) is the most effective powerful known professional antigen-presenting cell,and recent studies have found that DCs can also induce immune tolerance,and avoid or reduce the degree of transplant rejection.The aim of this study was to evaluate the effect of transfused immature CD4+ DCs on renal allografts in the rat model.Methods In this study,we induced CD4+ immature DCs from rat bone marrow cells by a cytokine cocktail.The immature CD4+ DCs were identified by morphological analysis and then the suppressive activity of these cells conditioned with donor kidney antigen was evaluated in vitro and in vivo.Results Immature CD4+ DCs conditioned with donor kidney antigen possessed immunosuppressive activity in vitro and they were able to prolong renal transplant survival in an allograft rat model in vivo.Conclusions Our study provides new information on efficacious renal transplantation,which might be useful for understanding the function of immature CD4+ DCs in modulating renal transplant rejection and improving clinical outcome in future studies.

  16. Human primary brain tumor cell growth inhibition in serum-free medium optimized for neuron survival.

    Science.gov (United States)

    Brewer, Gregory J; LeRoux, Peter D

    2007-07-09

    Glioblastoma is the most common primary brain tumor in adults from which about 15,000 patients die each year in the United States. Despite aggressive surgery, radiotherapy and chemotherapy, median survival remains only 1 year. Here we evaluate growth of primary human brain tumor cells in a defined nutrient culture medium (Neuregen) that was optimized for neuron regeneration. We hypothesized that Neuregen would inhibit tumor cell growth because of its ability to inhibit gliosis in rat brain. Tumor tissue was collected from 18 patients including 10 males and 8 females (mean age 60+/-12 years) who underwent craniotomy for newly diagnosed, histologically confirmed brain tumors. The tissue was shipped overnight in Hibernate transport medium. Tumor cells were isolated and plated in Neurobasal/serum or Neuregen on culture plastic. After 1 week, growth in Neuregen was significantly less in 9/10 glioblastoma multiforme cases, 5/5 meningioma cases and 3/3 cases of brain metastasis. Analysis of deficient formulations of Neuregen and formulations to which selected components were added back implicate no single active component. However, individual cases were sensitive to corticosterone, selenium, ethanolamine, fatty acids and/or antioxidants. Therefore, a defined culture medium that promotes neuron regeneration inhibits the growth of human primary glioblastoma, meningioma and metastatic tumor cells in culture. The possible in vivo efficacy of Neuregen for treatment of brain tumor resections remains to be determined.

  17. Interplay among nitric oxide and reactive oxygen species: a complex network determining cell survival or death.

    Science.gov (United States)

    Zhao, Jian

    2007-11-01

    Programmed cell death (PCD) is an integrated cellular process occurring in plant growth, development, and defense responses to facilitate normal growth and development and better survival against various stresses as a whole. As universal toxic chemicals in plant and animal cells, reactive oxygen or nitrogen species (ROS or RNS), mainly superoxide anion (O(2) (-*)), hydrogen peroxide (H(2)O(2)) or nitric oxide ((*)NO), have been studied extensively for their roles in PCD induction. Physiological and genetic studies have convincingly shown their essential roles. However, the details and mechanisms by which ROS and (*)NO interplay and induce PCD are not well understood. Our recent study on Cupressus lusitanica culture cell death revealed the elicitor-induced co-accumulation of ROS and (*)NO and interactions between (*)NO and H(2)O(2) or O(2)-(*) in different ways to regulate cell death. (*)NO and H(2)O(2) reciprocally enhanced the production of each other whereas (*)NO and O(2) (-*) showed reciprocal suppression on each other's production. It was the interaction between (*)NO and O(2)-(*) but not between (*)NO and H(2)O(2) that induced PCD, probably through peroxynitrite (ONOO(-)). In this addendum, some unsolved issues in the study were discussed based on recent studies on the complex network of ROS and (*)NO leading to PCD in animals and plants.

  18. Storage and survival of red blood cells with elevated sodium levels.

    Science.gov (United States)

    Wallas, C H; Harris, A S; Wetherall, N T

    1982-01-01

    Approximately 25 percent of black blood donors have an elevated red blood cell (RBC) sodium (Nai) level compared with white donors. This elevation results in a significant increase in the mean Nai from black (9.00 +/- 2.96 mmoles/l RBC) as compared to white blood donors (7.04 +/- 1.48 mmoles/l RBC, p less than 0.001). Red blood cells from four black donors with mean Nai levels of 15 +/- 2.8 mmoles/l RBC were stored for 35 days in citrate-phosphate-dextrose-adenine and compared to that of four donors with normal levels of Nai. Serial measurements of red blood cell adenosine triphosphate, diphosphoglycerate, glucose-6-phosphate dehydrogenase, pyruvic kinase, lactate production rates, and intracellular cations showed no differences between the two donor groups. Furthermore, the mean 24-hour posttransfusion survival was not significantly different for the high Nai group (83.2 +/- 5.6%) as compared with the control group (82.3 +/- 6.9%). Based on this study, it is not necessary to eliminate individuals with an elevated red blood cell Nai level as blood donors.

  19. Brachytherapy for stage IIIB squamous cell carcinoma of the uterine cervix: survival and toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Zuliani, Antonio Carlos; Cunha, Maercio de Oliveira, E-mail: aczo.rt@gmail.co [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Esteves, Sergio C.B. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Ciencias Medicas. Secao de Radioterapia; Teixeira, Julio Cesar [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Tocoginecologia

    2010-07-01

    Objective: to compare survival and toxicity of three different treatments for stage IIIB cervix cancer: low-dose-rate (LDR), high-dose-rate (HDR) brachytherapy and association of HDR and chemotherapy. Methods: between 1985 and 2005, 230 patients with FIGO stage IIIB squamous cell carcinoma of the uterine cervix received 4-field pelvic teletherapy at doses between 40 and 50.4 Gy, with a different complementation in each group. The LDRB group, with 42 patients, received one or two insertions of LDR, with Cesium-137, in a total dose of 80 to 100Gy at point A. The HDR group, 155 patients received HDR in 4 weekly 7 Gy fractions and 9 Gy to 14.4 Gy applied to the involved parametria. The CHT group, 33 patients, were given the same treatment as the HDR group and received 5 or 6 weekly cycles of cisplatin, 40 mg per m2. Results: the five-year progression-free survival (PFS) was 60% for the HDR group and 45% for the LDR group, and the two-year PFS for the CHT group was 65% (p = 0.02). The five-year Overall Survival (OS) was 65% for the HDR group and 49% for the LDR group. The two-year OS was 86% for the CHT group (p 0.02). Rectum toxicity grade II was 7% for the LDR group, 4% for the HDR group and 7% for the CHT group that had one case of rectum toxicity grade IV. Conclusion: patients that received HDR had better OS and PFS. The Chemotherapy-HDR association showed no benefit when compared to HDR only. Toxicity rates showed no difference between the three groups. (author)

  20. Fibroblast growth factor receptor 4 (FGFR4) and fibroblast growth factor 19 (FGF19) autocrine enhance breast cancer cells survival.

    Science.gov (United States)

    Tiong, Kai Hung; Tan, Boon Shing; Choo, Heng Lungh; Chung, Felicia Fei-Lei; Hii, Ling-Wei; Tan, Si Hoey; Khor, Nelson Tze Woei; Wong, Shew Fung; See, Sze-Jia; Tan, Yuen-Fen; Rosli, Rozita; Cheong, Soon-Keng; Leong, Chee-Onn

    2016-09-06

    Basal-like breast cancer is an aggressive tumor subtype with poor prognosis. The discovery of underlying mechanisms mediating tumor cell survival, and the development of novel agents to target these pathways, is a priority for patients with basal-like breast cancer. From a functional screen to identify key drivers of basal-like breast cancer cell growth, we identified fibroblast growth factor receptor 4 (FGFR4) as a potential mediator of cell survival. We found that FGFR4 mediates cancer cell survival predominantly via activation of PI3K/AKT. Importantly, a subset of basal-like breast cancer cells also secrete fibroblast growth factor 19 (FGF19), a canonical ligand specific for FGFR4. siRNA-mediated silencing of FGF19 or neutralization of extracellular FGF19 by anti-FGF19 antibody (1A6) decreases AKT phosphorylation, suppresses cancer cell growth and enhances doxorubicin sensitivity only in the FGFR4+/FGF19+ breast cancer cells. Consistently, FGFR4/FGF19 co-expression was also observed in 82 out of 287 (28.6%) primary breast tumors, and their expression is strongly associated with AKT phosphorylation, Ki-67 staining, higher tumor stage and basal-like phenotype. In summary, our results demonstrated the presence of an FGFR4/FGF19 autocrine signaling that mediates the survival of a subset of basal-like breast cancer cells and suggest that inactivation of this autocrine loop may potentially serve as a novel therapeutic intervention for future treatment of breast cancers.

  1. The MAP kinase pathway is required for entry into mitosis and cell survival.

    Science.gov (United States)

    Liu, Xiaoqi; Yan, Shi; Zhou, Tianhua; Terada, Yasuhiko; Erikson, Raymond L

    2004-01-22

    In this communication, we examined the role of the MAP kinase pathway in the G2/M phase of the cell cycle. Activation of the Plk1 and MAP kinase pathways was initially evaluated in FT210 cells, which arrest at G2 phase at the restrictive temperature (39 degrees C), due to a mutation in the cdc2 gene. Previous studies had shown that these cells enter mitosis at the nonpermissive temperature upon incubation with okadaic acid, a protein phosphatase 1 and 2A inhibitor. We show that treatment of FT210 cells at 39 degrees C with okadaic acid activated Plk1, as shown by hyperphosphorylation and elevated protein kinase activity, and also induced activation of the MAP kinase pathway. The specific Mek inhibitor PD98059 antagonized the okadaic acid-induced activation of both Plk1 and MAP kinases. This suggests that activation of the MAP kinase pathway may contribute to the okadaic acid-induced activation of Plk1 in FT210 cells at 39 degrees C. We also found that PD98059 strongly attenuated progression of HeLa cells through mitosis, and active Mek colocalizes with Plk1 at mitotic structures. To study the potential function of the MAP kinase pathway during mitosis, RNAi was used to specifically deplete five members of this pathway (Raf1, Mek1/2, Erk1/2). Each of these five protein kinases is required for cell proliferation and survival, and depletion of any of these proteins eventually leads to apoptosis. Treatment with Mek inhibitors also inhibited cell proliferation and caused apoptosis. A dramatic increase of Plk1 activities and a moderate increase of Cdc2 activities in Raf1-depleted cells indicate that Raf1-depleted cells arrest in the late G2 or M phase. Mek1 and Erk1 depletion also caused cell cycle arrest at G2, suggesting that these enzymes are required for the G2/M transition, whereas the loss of Mek2 or Erk2 caused arrest at G1.

  2. Protein kinase c-β-dependent activation of NF-κB in stromal cells is indispensable for the survival of chronic lymphocytic leukemia B cells in vivo.

    Science.gov (United States)

    Lutzny, Gloria; Kocher, Thomas; Schmidt-Supprian, Marc; Rudelius, Martina; Klein-Hitpass, Ludger; Finch, Andrew J; Dürig, Jan; Wagner, Michaela; Haferlach, Claudia; Kohlmann, Alexander; Schnittger, Susanne; Seifert, Marc; Wanninger, Stefan; Zaborsky, Nadja; Oostendorp, Robert; Ruland, Jürgen; Leitges, Michael; Kuhnt, Toni; Schäfer, Yvonne; Lampl, Benedikt; Peschel, Christian; Egle, Alexander; Ringshausen, Ingo

    2013-01-14

    Tumor cell survival critically depends on heterotypic communication with benign cells in the microenvironment. Here, we describe a survival signaling pathway activated in stromal cells by contact to B cells from patients with chronic lymphocytic leukemia (CLL). The expression of protein kinase C (PKC)-βII and the subsequent activation of NF-κB in bone marrow stromal cells are prerequisites to support the survival of malignant B cells. PKC-β knockout mice are insusceptible to CLL transplantations, underscoring the in vivo significance of the PKC-βII-NF-κB signaling pathway in the tumor microenvironment. Upregulated stromal PKC-βII in biopsies from patients with CLL, acute lymphoblastic leukemia, and mantle cell lymphoma suggests that this pathway may commonly be activated in a variety of hematological malignancies.

  3. Serotonin is a key factor for mouse red blood cell survival.

    Directory of Open Access Journals (Sweden)

    Pascal Amireault

    Full Text Available Serotonin (5-HT is a monoamine originally purified from blood as a vasoactive agent. In nonneuronal tissues, its presence is linked with the expression of tryptophan hydroxylase 1 (TPH1 that catalyzes the rate-limiting step of its synthesis. Targeted disruption in mice of the TPH1 gene results in very low levels of circulating 5-HT. Previous analysis of the TPH1 knockout (TPH1(-/- mouse revealed that they develop a phenotype of macrocytic anemia with a reduced half-life of their circulating red blood cells (RBC. In this study, to establish whether the observed reduced half-life of TPH1(-/- RBC is an intrinsic or an extrinsic characteristic, we compared their survival to RBC isolated from wild-type mice. Both in vivo and in vitro data converge to demonstrate an extrinsic protective effect of 5-HT since presence of 5-HT in the RBC environment protects RBC from senescence. The protective effect played by 5-HT is not mediated through activation of a classical pharmacological pathway as no 5-HT receptors were detected on isolated RBC. Rather, 5-HT acts as an effective antioxidant since reduction of 5-HT circulating levels are associated with a decrease in the plasma antioxidant capacity. We further demonstrate a link between oxidation and the removal of damaged RBC following transfusion, as supplementation with 5-HT improves RBC post-transfusion survival in a mouse model of blood banking.

  4. Microsomal PGE2 synthase-1 regulates melanoma cell survival and associates with melanoma disease progression.

    Science.gov (United States)

    Kim, Sun-Hee; Hashimoto, Yuuri; Cho, Sung-Nam; Roszik, Jason; Milton, Denái R; Dal, Fulya; Kim, Sangwon F; Menter, David G; Yang, Peiying; Ekmekcioglu, Suhendan; Grimm, Elizabeth A

    2016-05-01

    COX-2 and its product PGE2 enhance carcinogenesis and tumor progression, which has been previously reported in melanoma. As most COX inhibitors cause much toxicity, the downstream microsomal PGE2 synthase-1 (mPGES1) is a consideration for targeting. Human melanoma TMAs were employed for testing mPGES1 protein staining intensity and percentage levels, and both increased with clinical stage; employing a different Stage III TMA, mPGES1 intensity (not percentage) associated with reduced patient survival. Our results further show that iNOS was also highly expressed in melanoma tissues with high mPGES1 levels, and iNOS-mediated NO promoted mPGES1 expression and PGE2 production. An mPGES1-specific inhibitor (CAY10526) as well as siRNA attenuated cell survival and increased apoptosis. CAY10526 significantly suppressed tumor growth and increased apoptosis in melanoma xenografts. Our findings support the value of a prognostic and predictive role for mPGES1, and suggest targeting this molecule in the PGE2 pathway as another avenue toward improving melanoma therapy.

  5. Significant Improvement in Survival after Unrelated Donor Hematopoietic Cell Transplantation in the Recent Era

    Science.gov (United States)

    Majhail, Navneet S; Chitphakdithai, Pintip; Logan, Brent; King, Roberta; Devine, Steven; Rossmann, Susan N; Hale, Gregory; Hartzman, Robert J; Karanes, Chatchada; Laport, Ginna G; Nemecek, Eneida; Snyder, Edward L; Switzer, Galen E; Miller, John; Navarro, Willis; Confer, Dennis L; Levine, John E

    2014-01-01

    Patients and physicians may defer unrelated donor hematopoietic cell transplantation (HCT) as curative therapy due to mortality risk associated with the procedure. Therefore, it is important for physicians to know the current outcomes data when counseling potential candidates. To provide this information, we evaluated 15,059 unrelated donor HCT recipients between 2000-2009. We compared outcomes before and after 2005 for four cohorts: age <18 years with malignant diseases (N=1,920), 18-59 years with malignant diseases (N=9,575), ≥60 years with malignant diseases (N=2,194), and non-malignant diseases (N=1,370). Three-year overall survival in 2005-2009 was significantly better in all four cohorts (<18 years: 55% vs. 45%, 18-59 years: 42% vs. 35%, ≥60 years: 35% vs. 25%, non-malignant diseases: 69% vs. 60%, P<0.001 for all comparisons). Multivariate analyses in leukemia patients receiving HLA 7-8/8 matched transplants showed significant reduction in overall and non-relapse mortality in the first 1-year after HCT among patients transplanted in 2005-2009; however, risks for relapse did not change over time. Significant survival improvements after unrelated donor HCT have occurred over the recent decade and can be partly explained by better patient selection (e.g., HCT earlier in the disease course and lower disease risk), improved donor selection (e.g., more precise allele-level matched unrelated donors) and changes in transplant practices. PMID:25445638

  6. Effects of common germ-line genetic variation in cell cycle genes on ovarian cancer survival

    DEFF Research Database (Denmark)

    Song, H.; Hogdall, E.; Ramus, S.J.;

    2008-01-01

    plausibly influence clinical characteristics of multiple tumors types. EXPERIMENTAL DESIGN: We examined associations between common germ-line genetic variation in 14 genes involved in cell cycle pathway (CCND1, CCND2, CCND3, CCNE1, CDKN1A, CDKN1B, CDKN2A, CDKN2B, CDKN2C, CDKN2D, CDK2, CDK4, CDK6, and RB1.......05) in these genes. The genotypes of each polymorphism were tested for association with survival by Cox regression analysis. RESULTS: A nominally statistically significant association between genotype and ovarian cancer survival was observed for polymorphisms in CCND2 and CCNE1. The per-allele hazard ratios (95......% confidence intervals) were 1.16 (1.03-1.31; P = 0.02) for rs3217933, 1.14 (1.02-1.27; P = 0.024) for rs3217901, and 0.85 (0.73-1.00; P = 0.043) for rs3217862 in CCND2 and 1.39 (1.04-1.85; P = 0.033) for rs3218038 in CCNE1. However, these were not significant after adjusting for multiple hypothesis tests...

  7. Distribution of mesenchymal stem cells and effects on neuronal survival and axon regeneration after optic nerve crush and cell therapy.

    Directory of Open Access Journals (Sweden)

    Louise Alessandra Mesentier-Louro

    Full Text Available Bone marrow-derived cells have been used in different animal models of neurological diseases. We investigated the therapeutic potential of mesenchymal stem cells (MSC injected into the vitreous body in a model of optic nerve injury. Adult (3-5 months old Lister Hooded rats underwent unilateral optic nerve crush followed by injection of MSC or the vehicle into the vitreous body. Before they were injected, MSC were labeled with a fluorescent dye or with superparamagnetic iron oxide nanoparticles, which allowed us to track the cells in vivo by magnetic resonance imaging. Sixteen and 28 days after injury, the survival of retinal ganglion cells was evaluated by assessing the number of Tuj1- or Brn3a-positive cells in flat-mounted retinas, and optic nerve regeneration was investigated after anterograde labeling of the optic axons with cholera toxin B conjugated to Alexa 488. Transplanted MSC remained in the vitreous body and were found in the eye for several weeks. Cell therapy significantly increased the number of Tuj1- and Brn3a-positive cells in the retina and the number of axons distal to the crush site at 16 and 28 days after optic nerve crush, although the RGC number decreased over time. MSC therapy was associated with an increase in the FGF-2 expression in the retinal ganglion cells layer, suggesting a beneficial outcome mediated by trophic factors. Interleukin-1β expression was also increased by MSC transplantation. In summary, MSC protected RGC and stimulated axon regeneration after optic nerve crush. The long period when the transplanted cells remained in the eye may account for the effect observed. However, further studies are needed to overcome eventually undesirable consequences of MSC transplantation and to potentiate the beneficial ones in order to sustain the neuroprotective effect overtime.

  8. DNA-damage response gene GADD45A induces differentiation in hematopoietic stem cells without inhibiting cell cycle or survival.

    Science.gov (United States)

    Wingert, Susanne; Thalheimer, Frederic B; Haetscher, Nadine; Rehage, Maike; Schroeder, Timm; Rieger, Michael A

    2016-03-01

    Hematopoietic stem cells (HSCs) maintain blood cell production life-long by their unique abilities of self-renewal and differentiation into all blood cell lineages. Growth arrest and DNA-damage-inducible 45 alpha (GADD45A) is induced by genotoxic stress in HSCs. GADD45A has been implicated in cell cycle control, cell death and senescence, as well as in DNA-damage repair. In general, GADD45A provides cellular stability by either arresting the cell cycle progression until DNA damage is repaired or, in cases of fatal damage, by inducing apoptosis. However, the function of GADD45A in hematopoiesis remains controversial. We revealed the changes in murine HSC fate control orchestrated by the expression of GADD45A at single cell resolution. In contrast to other cellular systems, GADD45A expression did not cause a cell cycle arrest or an alteration in the decision between cell survival and apoptosis in HSCs. Strikingly, GADD45A strongly induced and accelerated the differentiation program in HSCs. Continuous tracking of individual HSCs and their progeny via time-lapse microscopy elucidated that once GADD45A was expressed, HSCs differentiate into committed progenitors within 29 hours. GADD45A-expressing HSCs failed to long-term reconstitute the blood of recipients by inducing multilineage differentiation in vivo. Importantly, γ-irradiation of HSCs induced their differentiation by upregulating endogenous GADD45A. The differentiation induction by GADD45A was transmitted by activating p38 Mitogen-activated protein kinase (MAPK) signaling and allowed the generation of megakaryocytic-erythroid, myeloid, and lymphoid lineages. These data indicate that genotoxic stress-induced GADD45A expression in HSCs prevents their fatal transformation by directing them into differentiation and thereby clearing them from the system.

  9. Entrance and survival of Brucella pinnipedialis hooded seal strain in human macrophages and epithelial cells.

    Directory of Open Access Journals (Sweden)

    Anett K Larsen

    Full Text Available Marine mammal Brucella spp. have been isolated from pinnipeds (B. pinnipedialis and cetaceans (B. ceti from around the world. Although the zoonotic potential of marine mammal brucellae is largely unknown, reports of human disease exist. There are few studies of the mechanisms of bacterial intracellular invasion and multiplication involving the marine mammal Brucella spp. We examined the infective capacity of two genetically different B. pinnipedialis strains (reference strain; NTCT 12890 and a hooded seal isolate; B17 by measuring the ability of the bacteria to enter and replicate in cultured phagocytes and epithelial cells. Human macrophage-like cells (THP-1, two murine macrophage cell lines (RAW264.7 and J774A.1, and a human malignant epithelial cell line (HeLa S3 were challenged with bacteria in a gentamicin protection assay. Our results show that B. pinnipedialis is internalized, but is then gradually eliminated during the next 72-96 hours. Confocal microscopy revealed that intracellular B. pinnipedialis hooded seal strain colocalized with lysosomal compartments at 1.5 and 24 hours after infection. Intracellular presence of B. pinnipedialis hooded seal strain was verified by transmission electron microscopy. By using a cholesterol-scavenging lipid inhibitor, entrance of B. pinnipedialis hooded seal strain in human macrophages was significantly reduced by 65.8 % (± 17.3, suggesting involvement of lipid-rafts in intracellular entry. Murine macrophages invaded by B. pinnipedialis do not release nitric oxide (NO and intracellular bacterial presence does not induce cell death. In summary, B. pinnipedialis hooded seal strain can enter human and murine macrophages, as well as human epithelial cells. Intracellular entry of B. pinnipedialis hooded seal strain involves, but seems not to be limited to, lipid-rafts in human macrophages. Brucella pinnipedialis does not multiply or survive for prolonged periods intracellulary.

  10. Specific inhibition of TRPV4 enhances retinal ganglion cell survival in adult porcine retinal explants.

    Science.gov (United States)

    Taylor, Linnéa; Arnér, Karin; Ghosh, Fredrik

    2017-01-01

    Signaling through the polymodal cation channel Transient Receptor Potential Vanilloid 4 (TRPV4) has been implicated in retinal neuronal degeneration. To further outline the involvement of this channel in this process, we here explore modulation of Transient Receptor Potential Vanilloid 4 (TRPV4) activity on neuronal health and glial activation in an in vitro model of retinal degeneration. For this purpose, adult porcine retinal explants were cultured using a previously established standard protocol for up to 5 days with specific TRPV4 agonist GSK1016790A (GSK), or specific antagonist RN-1734, or culture medium only. Glial and neuronal cell health were evaluated by a battery of immunohistochemical markers, as well as morphological staining. Specific inhibition of TRPV4 by RN-1734 significantly enhanced ganglion cell survival, improved the maintenance of the retinal laminar architecture, reduced apoptotic cell death and attenuated the gliotic response as well as preserved the expression of TRPV4 in the plexiform layers and ganglion cells. In contrast, culture controls, as well as specimens treated with GSK, displayed rapid remodeling and neurodegeneration as well as a downregulation of TRPV4 and the Müller cell homeostatic mediator glutamine synthetase. Our results indicate that TRPV4 signaling is an important contributor to the retinal degeneration in this model, affecting neuronal cell health and glial homeostasis. The finding that pharmacological inhibition of the receptor significantly attenuates neuronal degeneration and gliosis in vitro, suggests that TRPV4 signaling may be an interesting pharmaceutical target to explore for treatment of retinal degenerative disease.

  11. Elevated maspin expression is associated with better overall survival in esophageal squamous cell carcinoma (ESCC.

    Directory of Open Access Journals (Sweden)

    Yang Wang

    Full Text Available Tumor suppressor maspin is a differentially regulated gene in the progression of many types of cancer. While the biological function of maspin in blocking tumor invasion and metastasis is consistent with the loss of maspin expression at the late stage of tumor progression, the differential expression and the biological significance of maspin in early stage of tumor progression appear to be complex and remain to be elucidated. In the current study, we examined the expression of maspin in 84 esophageal squamous cell carcinoma (ESCC cases (stages I-III and 55 non-tumor adjacent esophageal tissue specimens by immunohistochemical (IHC staining. The correlation of maspin with clinicopathological parameters was analyzed. Compared to normal esophageal squamous tissue where 80% (47/55 of the cases expressed maspin at a low to moderate level, all ESCC specimens (100% (84/84 were positive for maspin expression at a moderate to high level. ESCC with low or moderate maspin expression had significantly shorter postoperative survival rates compared to those that had high maspin expression (p<0.001. Since the correlation of maspin with ESCC histology and the correlation of maspin with ESCC prognosis seem to be at odds, we further investigated the biological function of maspin in ESCC using the established ESCC cell lines. The expression of maspin in five human esophageal squamous cancer cell lines (T12, E450, KYSE150, EC109, and KYSE510 was examined by the Western blot. ESCC cell line KYSE510 that did not express maspin and was stably transfected by maspin cDNA or an empty vector. The resulting transfected cells were characterized in vitro. Maspin expression significantly inhibited cell proliferation, motility and matrigel invasion. Taken together, our data suggest that the transient up-regulation of maspin in the early development of ESCC may be a defense mechanism against further transition towards more malignant phenotypes, ultimately slowing down ESCC tumor

  12. Elevated maspin expression is associated with better overall survival in esophageal squamous cell carcinoma (ESCC).

    Science.gov (United States)

    Wang, Yang; Sheng, Shijie; Zhang, Jianzhi; Dzinic, Sijana; Li, Shaolei; Fang, Fang; Wu, Nan; Zheng, Qingfeng; Yang, Yue

    2013-01-01

    Tumor suppressor maspin is a differentially regulated gene in the progression of many types of cancer. While the biological function of maspin in blocking tumor invasion and metastasis is consistent with the loss of maspin expression at the late stage of tumor progression, the differential expression and the biological significance of maspin in early stage of tumor progression appear to be complex and remain to be elucidated. In the current study, we examined the expression of maspin in 84 esophageal squamous cell carcinoma (ESCC) cases (stages I-III) and 55 non-tumor adjacent esophageal tissue specimens by immunohistochemical (IHC) staining. The correlation of maspin with clinicopathological parameters was analyzed. Compared to normal esophageal squamous tissue where 80% (47/55) of the cases expressed maspin at a low to moderate level, all ESCC specimens (100% (84/84)) were positive for maspin expression at a moderate to high level. ESCC with low or moderate maspin expression had significantly shorter postoperative survival rates compared to those that had high maspin expression (pESCC histology and the correlation of maspin with ESCC prognosis seem to be at odds, we further investigated the biological function of maspin in ESCC using the established ESCC cell lines. The expression of maspin in five human esophageal squamous cancer cell lines (T12, E450, KYSE150, EC109, and KYSE510) was examined by the Western blot. ESCC cell line KYSE510 that did not express maspin and was stably transfected by maspin cDNA or an empty vector. The resulting transfected cells were characterized in vitro. Maspin expression significantly inhibited cell proliferation, motility and matrigel invasion. Taken together, our data suggest that the transient up-regulation of maspin in the early development of ESCC may be a defense mechanism against further transition towards more malignant phenotypes, ultimately slowing down ESCC tumor progression.

  13. Inhibition of SIRT1 Catalytic Activity Increases p53 Acetylation but Does Not Alter Cell Survival following DNA Damage

    Science.gov (United States)

    Solomon, Jonathan M.; Pasupuleti, Rao; Xu, Lei; McDonagh, Thomas; Curtis, Rory; DiStefano, Peter S.; Huber, L. Julie

    2006-01-01

    Human SIRT1 is an enzyme that deacetylates the p53 tumor suppressor protein and has been suggested to modulate p53-dependent functions including DNA damage-induced cell death. In this report, we used EX-527, a novel, potent, and specific small-molecule inhibitor of SIRT1 catalytic activity to examine the role of SIRT1 in p53 acetylation and cell survival after DNA damage. Treatment with EX-527 dramatically increased acetylation at lysine 382 of p53 after different types of DNA damage in primary human mammary epithelial cells and several cell lines. Significantly, inhibition of SIRT1 catalytic activity by EX-527 had no effect on cell growth, viability, or p53-controlled gene expression in cells treated with etoposide. Acetyl-p53 was also increased by the histone deacetylase (HDAC) class I/II inhibitor trichostatin A (TSA). EX-527 and TSA acted synergistically to increase acetyl-p53 levels, confirming that p53 acetylation is regulated by both SIRT1 and HDACs. While TSA alone reduced cell survival after DNA damage, the combination of EX-527 and TSA had no further effect on cell viability and growth. These results show that, although SIRT1 deacetylates p53, this does not play a role in cell survival following DNA damage in certain cell lines and primary human mammary epithelial cells. PMID:16354677

  14. Survival after T cell-depleted haploidentical stem cell transplantation is improved using the mother as donor.

    Science.gov (United States)

    Stern, Martin; Ruggeri, Loredana; Mancusi, Antonella; Bernardo, Maria Ester; de Angelis, Claudia; Bucher, Christoph; Locatelli, Franco; Aversa, Franco; Velardi, Andrea

    2008-10-01

    We hypothesized that transplacental leukocyte trafficking during pregnancy, which induces long-term, stable, reciprocal microchimerism in mother and child, might influence outcome of patients with acute leukemia given parental donor haploidentical hematopoietic stem cell transplantation (HSCT). We analyzed the outcome of 118 patients who received transplants for acute leukemia in 2 centers. Patients received highly T cell-depleted haploidentical grafts after myelo-ablative conditioning. Five-year event-free survival was better in patients who received transplants from the mother than from the father (50.6% +/- 7.6% vs 11.1% +/- 4.2%; P mother = 2.36; P = .003). In contrast, in a control cohort of patients who received transplants from haploidentical siblings, donor sex had no influence on outcome. Although obtained in a retrospective analysis, these data suggest that the mother of the patient should be preferred as donor for haploidentical HSCT.

  15. Graphene derivative scaffolds facilitate in vitro cell survival and maturation of dopaminergic SN4741 cells

    OpenAIRE

    Rodriguez-Losada, Noela; Wendelbo, Rune; Garcia-fernandez, Maria; Pavia, Jose; Martinez-Montañez, Elisa; Lara Muñoz, José Pablo; Arenas, Ernest; Aguirre, José A.

    2014-01-01

    The emerging carbon nanomaterial Graphene (G), in the form of scaffold structure, has an efficient bioconjugation with common biomolecules and activates cell differentiation of neuronal stem cells, providing a promising approach for neural regeneration. We propose the use of G as a scaffold to re-address the dopaminergic (DA) neurons and the residual axons from dead or apoptotic DA neurons in Parkinson´s disease (PD). G could act as a physical support to promote the axonal sprout as a “decele...

  16. Wnt-11 promotes neuroendocrine-like differentiation, survival and migration of prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Diez Soraya

    2010-03-01

    expression of Wnt-11 promoted LNCaP cell invasion. Conclusions These observations suggest that the increased level of Wnt-11 found in prostate cancer contributes to tumour progression by promoting NED, tumour cell survival and cell migration/invasion, and may provide an opportunity for novel therapy in prostate cancer.

  17. Nivolumab versus Cabozantinib: Comparing Overall Survival in Metastatic Renal Cell Carcinoma.

    Directory of Open Access Journals (Sweden)

    Witold Wiecek

    Full Text Available Renal-cell carcinoma (RCC affects over 330,000 new patients every year, of whom 1/3 present with metastatic RCC (mRCC at diagnosis. Most mRCC patients treated with a first-line agent relapse within 1 year and need second-line therapy. The present study aims to compare overall survival (OS between nivolumab and cabozantinib from two recent pivotal studies comparing, respectively, each one of the two emerging treatments against everolimus in patients who relapse following first-line treatment. Comparison is traditionally carried out using the Bucher method, which assumes proportional hazard. Since OS curves intersected in one of the pivotal studies, models not assuming proportional hazards were also considered to refine the comparison. Four Bayesian parametric survival network meta-analysis models were implemented on overall survival (OS data digitized from the Kaplan-Meier curves reported in the studies. Three models allowing hazard ratios (HR to vary over time were assessed against a fixed-HR model. The Bucher method favored cabozantinib, with a fixed HR for OS vs. nivolumab of 1.09 (95% confidence interval: [0.77, 1.54]. However, all models with time-varying HR showed better fits than the fixed-HR model. The log-logistic model fitted the data best, exhibiting a HR for OS initially favoring cabozantinib, the trend inverting to favor nivolumab after month 5 (95% credible interval <1 from 10 months. The initial probability of cabozantinib conferring superior OS was 54%, falling to 41.5% by month 24. Numerical differences in study-adjusted OS estimates between the two treatments remained small. This study evidences that HR for OS of nivolumab vs. cabozantinib varies over time, favoring cabozantinib in the first months of treatment but nivolumab afterwards, a possible indication that patients with poor prognosis benefit more from cabozantinib in terms of survival, nivolumab benefiting patients with better prognosis. More evidence, including real

  18. Active Stat3 is required for survival of human squamous cell carcinoma cells in serum-free conditions

    Directory of Open Access Journals (Sweden)

    DiGiovanni John

    2006-04-01

    Full Text Available Abstract Background Squamous cell carcinoma (SCC of the skin is the most aggressive form of non-melanoma skin cancer (NMSC, and is the single most commonly diagnosed cancer in the U.S., with over one million new cases reported each year. Recent studies have revealed an oncogenic role of activated signal transducer and activator of transcription 3 (Stat3 in many human tumors, especially in those of epithelial origin, including skin SCC. Stat3 is a mediator of numerous growth factor and cytokine signaling pathways, all of which activate it through phosphorylation of tyrosine 705. Results To further address the role of Stat3 in skin SCC tumorigenesis, we have analyzed a panel of human skin-derived cell lines ranging from normal human epidermal keratinocytes (NHEK, to non-tumorigenic transformed skin cells (HaCaT, to highly tumorigenic cells (SRB1-m7 and SRB12-p9 and observed a positive correlation between Stat3 phosphorylation and SCC malignancy. We next determined the role of Stat3 activity in cell proliferation and viability under serum-free culture conditions. This was accomplished by suppressing Stat3 activity in the SRB12-p9 cells through stable expression of a dominant negative acting form of Stat3β, which contains a tyrosine 705 to phenylalanine mutation (S3DN. The S3DN cells behaved similar to parental SRB12-p9 cells when cultured in optimal growth conditions, in the presence of 10% fetal calf serum. However, unlike the SRB12-p9 cells, S3DN cells underwent apoptotic cell death when cultured in serum-free medium (SFM. This was evidenced by multiple criteria, including accumulation of sub-G1 particles, induced PARP cleavage, and acquisition of the characteristic morphological changes associated with apoptosis. Conclusion This study provides direct evidence for a role for Stat3 in maintaining cell survival in the conditions of exogenous growth factor deprivation produced by culture in SFM. We also propose that delivery of the S3DN gene or

  19. Host cell phosphatidylcholine is a key mediator of malaria parasite survival during liver stage infection.

    Science.gov (United States)

    Itoe, Maurice A; Sampaio, Júlio L; Cabal, Ghislain G; Real, Eliana; Zuzarte-Luis, Vanessa; March, Sandra; Bhatia, Sangeeta N; Frischknecht, Friedrich; Thiele, Christoph; Shevchenko, Andrej; Mota, Maria M

    2014-12-10

    During invasion, Plasmodium, the causative agent of malaria, wraps itself in a parasitophorous vacuole membrane (PVM), which constitutes a critical interface between the parasite and its host cell. Within hepatocytes, each Plasmodium sporozoite generates thousands of new parasites, creating high demand for lipids to support this replication and enlarge the PVM. Here, a global analysis of the total lipid repertoire of Plasmodium-infected hepatocytes reveals an enrichment of neutral lipids and the major membrane phospholipid, phosphatidylcholine (PC). While infection is unaffected in mice deficient in key enzymes involved in neutral lipid synthesis and lipolysis, ablation of rate-limiting enzymes in hepatic PC biosynthetic pathways significantly decreases parasite numbers. Host PC is taken up by both P. berghei and P. falciparum and is necessary for correct localization of parasite proteins to the PVM, which is essential for parasite survival. Thus, Plasmodium relies on the abundance of these lipids within hepatocytes to support infection.

  20. Overall survival after immunotherapy, tyrosine kinase inhibitors and surgery in treatment of metastatic renal cell cancer

    DEFF Research Database (Denmark)

    de Lichtenberg, Trine Honnens; Hermann, Gregers G.; Rorth, Mikael

    2014-01-01

    -three consecutive mRCC patients were given immunotherapy (n = 59), TKIs (n = 49) or sequential therapy (IMM→TKI group; n = 35). The TKI group included patients with higher age (p ... of metastases and sites and tumour histology did not differ between groups. Results. First line immunotherapy gave a median OS of 16.3 months and first line TKIs 10.9 months (p = 0.003). Survival longer than 5 years was limited to immunotherapy. Sarcomatoid component, metastatic sites, papillary histology......, stage, performance status and white cell blood count were related to poor OS. Using multivariate analyses to adjust for risk predictors the difference in OS disappeared. Median OS before and after introduction of TKIs was 16 months and 14 months, respectively (p = 0.189). Memorial Sloan Kettering Cancer...

  1. A Validated Prediction Model for Overall Survival From Stage III Non-Small Cell Lung Cancer: Toward Survival Prediction for Individual Patients

    Energy Technology Data Exchange (ETDEWEB)

    Oberije, Cary, E-mail: cary.oberije@maastro.nl [Radiation Oncology, Research Institute GROW of Oncology, Maastricht University Medical Center, Maastricht (Netherlands); De Ruysscher, Dirk [Radiation Oncology, Research Institute GROW of Oncology, Maastricht University Medical Center, Maastricht (Netherlands); Universitaire Ziekenhuizen Leuven, KU Leuven (Belgium); Houben, Ruud [Radiation Oncology, Research Institute GROW of Oncology, Maastricht University Medical Center, Maastricht (Netherlands); Heuvel, Michel van de; Uyterlinde, Wilma [Department of Thoracic Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Deasy, Joseph O. [Memorial Sloan Kettering Cancer Center, New York (United States); Belderbos, Jose [Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Dingemans, Anne-Marie C. [Department of Pulmonology, University Hospital Maastricht, Research Institute GROW of Oncology, Maastricht (Netherlands); Rimner, Andreas; Din, Shaun [Memorial Sloan Kettering Cancer Center, New York (United States); Lambin, Philippe [Radiation Oncology, Research Institute GROW of Oncology, Maastricht University Medical Center, Maastricht (Netherlands)

    2015-07-15

    Purpose: Although patients with stage III non-small cell lung cancer (NSCLC) are homogeneous according to the TNM staging system, they form a heterogeneous group, which is reflected in the survival outcome. The increasing amount of information for an individual patient and the growing number of treatment options facilitate personalized treatment, but they also complicate treatment decision making. Decision support systems (DSS), which provide individualized prognostic information, can overcome this but are currently lacking. A DSS for stage III NSCLC requires the development and integration of multiple models. The current study takes the first step in this process by developing and validating a model that can provide physicians with a survival probability for an individual NSCLC patient. Methods and Materials: Data from 548 patients with stage III NSCLC were available to enable the development of a prediction model, using stratified Cox regression. Variables were selected by using a bootstrap procedure. Performance of the model was expressed as the c statistic, assessed internally and on 2 external data sets (n=174 and n=130). Results: The final multivariate model, stratified for treatment, consisted of age, gender, World Health Organization performance status, overall treatment time, equivalent radiation dose, number of positive lymph node stations, and gross tumor volume. The bootstrapped c statistic was 0.62. The model could identify risk groups in external data sets. Nomograms were constructed to predict an individual patient's survival probability ( (www.predictcancer.org)). The data set can be downloaded at (https://www.cancerdata.org/10.1016/j.ijrobp.2015.02.048). Conclusions: The prediction model for overall survival of patients with stage III NSCLC highlights the importance of combining patient, clinical, and treatment variables. Nomograms were developed and validated. This tool could be used as a first building block for a decision support system.

  2. MicroRNA-497 impairs the growth of chemoresistant neuroblastoma cells by targeting cell cycle, survival and vascular permeability genes

    Science.gov (United States)

    Soriano, Aroa; París-Coderch, Laia; Jubierre, Luz; Martínez, Alba; Zhou, Xiangyu; Piskareva, Olga; Bray, Isabella; Vidal, Isaac; Almazán-Moga, Ana; Molist, Carla; Roma, Josep; Bayascas, José R.; Casanovas, Oriol; Stallings, Raymond L.; de Toledo, José Sánchez; Gallego, Soledad; Segura, Miguel F.

    2016-01-01

    Despite multimodal therapies, a high percentage of high-risk neuroblastoma (NB) become refractory to current treatments, most of which interfere with cell cycle and DNA synthesis or function, activating the DNA damage response (DDR). In cancer, this process is frequently altered by deregulated expression or function of several genes which contribute to multidrug resistance (MDR). MicroRNAs are outstanding candidates for therapy since a single microRNA can modulate the expression of multiple genes of the same or different pathways, thus hindering the development of resistance mechanisms by the tumor. We found several genes implicated in the MDR to be overexpressed in high-risk NB which could be targeted by microRNAs simultaneously. Our functional screening identified several of those microRNAs that reduced proliferation of chemoresistant NB cell lines, the best of which was miR-497. Low expression of miR-497 correlated with poor patient outcome. The overexpression of miR-497 reduced the proliferation of multiple chemoresistant NB cell lines and induced apoptosis in MYCN-amplified cell lines. Moreover, the conditional expression of miR-497 in NB xenografts reduced tumor growth and inhibited vascular permeabilization. MiR-497 targets multiple genes related to the DDR, cell cycle, survival and angiogenesis, which renders this molecule a promising candidate for NB therapy. PMID:26824183

  3. SIGNIFICANT IMPROVEMENT OF THE SURVIVAL OF SEMINOMA CELLS-INVITRO BY USE OF A RAT SERTOLI-CELL FEEDER LAYER AND SERUM-FREE MEDIUM

    NARCIS (Netherlands)

    BERENDS, JC; SCHUTTE, SE; VANDISSELEMILIANI, FMF; DEROOIJ, DG; LOOIJENGA, LHJ; OOSTERHUIS, JW

    1991-01-01

    Seminoma cell lines, essential to the study of the biology of seminoma, do not exist. Tissue culture conditions for establishing such cell lines have to be developed. Under conventional culture conditions, seminoma cells usually die within the first 3 days after plating. The enhanced survival of rat

  4. RNA-Seq Analysis of Sulfur-Deprived Chlamydomonas Cells Reveals Aspects of Acclimation Critical for Cell Survival[W

    Science.gov (United States)

    González-Ballester, David; Casero, David; Cokus, Shawn; Pellegrini, Matteo; Merchant, Sabeeha S.; Grossman, Arthur R.

    2010-01-01

    The Chlamydomonas reinhardtii transcriptome was characterized from nutrient-replete and sulfur-depleted wild-type and snrk2.1 mutant cells. This mutant is null for the regulatory Ser-Thr kinase SNRK2.1, which is required for acclimation of the alga to sulfur deprivation. The transcriptome analyses used microarray hybridization and RNA-seq technology. Quantitative RT-PCR evaluation of the results obtained by these techniques showed that RNA-seq reports a larger dynamic range of expression levels than do microarray hybridizations. Transcripts responsive to sulfur deprivation included those encoding proteins involved in sulfur acquisition and assimilation, synthesis of sulfur-containing metabolites, Cys degradation, and sulfur recycling. Furthermore, we noted potential modifications of cellular structures during sulfur deprivation, including the cell wall and complexes associated with the photosynthetic apparatus. Moreover, the data suggest that sulfur-deprived cells accumulate proteins with fewer sulfur-containing amino acids. Most of the sulfur deprivation responses are controlled by the SNRK2.1 protein kinase. The snrk2.1 mutant exhibits a set of unique responses during both sulfur-replete and sulfur-depleted conditions that are not observed in wild-type cells; the inability of this mutant to acclimate to S deprivation probably leads to elevated levels of singlet oxygen and severe oxidative stress, which ultimately causes cell death. The transcriptome results for wild-type and mutant cells strongly suggest the occurrence of massive changes in cellular physiology and metabolism as cells become depleted for sulfur and reveal aspects of acclimation that are likely critical for cell survival. PMID:20587772

  5. Nubp1 is required for lung branching morphogenesis and distal progenitor cell survival in mice.

    Directory of Open Access Journals (Sweden)

    Carsten Schnatwinkel

    Full Text Available The lung is a complex system in biology and medicine alike. Whereas there is a good understanding of the anatomy and histology of the embryonic and adult lung, less is known about the molecular details and the cellular pathways that ultimately orchestrate lung formation and affect its health. From a forward genetic approach to identify novel genes involved in lung formation, we identified a mutated Nubp1 gene, which leads to syndactyly, eye cataract and lung hypoplasia. In the lung, Nubp1 is expressed in progenitor cells of the distal epithelium. Nubp1(m1Nisw mutants show increased apoptosis accompanied by a loss of the distal progenitor markers Sftpc, Sox9 and Foxp2. In addition, Nubp1 mutation disrupts localization of the polarity protein Par3 and the mitosis relevant protein Numb. Using knock-down studies in lung epithelial cells, we also demonstrate a function of Nubp1 in regulating centrosome dynamics and microtubule organization. Together, Nubp1 represents an essential protein for lung progenitor survival by coordinating vital cellular processes including cell polarity and centrosomal dynamics.

  6. Molecular Imaging of Bone Marrow Mononuclear Cell Survival and Homing in Murine Peripheral Artery Disease

    Science.gov (United States)

    van der Bogt, Koen E.A.; Hellingman, Alwine A.; Lijkwan, Maarten A.; Bos, Ernst-Jan; de Vries, Margreet R.; Fischbein, Michael P.; Quax, Paul H.; Robbins, Robert C.; Hamming, Jaap F.; Wu, Joseph C.

    2013-01-01

    Introduction Bone marrow mononuclear cell (MNC) therapy is a promising treatment for peripheral artery disease (PAD). This study aims to provide insight into cellular kinetics using molecular imaging following different transplantation methods. Methods and Results MNCs were isolated from F6 transgenic mice (FVB background) that express firefly luciferase (Fluc) and green fluorescence protein (GFP). Male FVB and C57Bl6 mice (n=50) underwent femoral artery ligation and were randomized into 4 groups receiving: (1) single intramuscular (i.m.) injection of 2×106 MNC; (2) four weekly i.m. injections of 5×105 MNC; (3) 2×106 MNCs intravenously (i.v.); and (4) PBS. Cellular kinetics, measured by in vivo bioluminescence imaging (BLI), revealed near-complete donor cell death 4 weeks after i.m. transplantation. Following i.v. transplantation, BLI monitored cells homed in on the injured area in the limb, as well as to the liver, spleen, and bone marrow. Ex vivo BLI showed presence of MNCs in the scar tissue and adductor muscle. However, no significant effects on neovascularisation were observed as monitored by Laser-Doppler-Perfusion-Imaging and histology. Conclusion This is one of the first studies to assess kinetics of transplanted MNCs in PAD using in vivo molecular imaging. MNC survival is short lived and MNCs do not significantly stimulate perfusion in this model. PMID:22239892

  7. SIRT1 is a critical regulator of K562 cell growth, survival, and differentiation.

    Science.gov (United States)

    Duncan, Mark T; DeLuca, Teresa A; Kuo, Hsin-Yu; Yi, Minchang; Mrksich, Milan; Miller, William M

    2016-05-15

    Inhibition of histone deacetylases (HDACi) has emerged as a promising approach in the treatment of many types of cancer, including leukemias. Among the HDACs, Class III HDACs, also known as sirtuins (SIRTs), are unique in that their function is directly related to the cell's metabolic state through their dependency on the co-factor NAD(+). In this study, we examined the relation between SIRTs and the growth, survival, and differentiation of K562 erythroleukemia cells. Using a mass spectrometry approach we previously developed, we show that SIRT expression and deacetylase activity in these cells changes greatly with differentiation state (undifferentiated vs. megakaryocytic differentiation vs. erythroid differentiation). Moreover, SIRT1 is crucially involved in regulating the differentiation state. Overexpression of wildtype (but not deacetylase mutant) SIRT1 resulted in upregulation of glycophorin A, ~2-fold increase in the mRNA levels of α, γ, ε, and ζ-globins, and spontaneous hemoglobinization. Hemin-induced differentiation was also enhanced by (and depended on) higher SIRT1 levels. Since K562 cells are bipotent, we also investigated whether SIRT1 modulation affected their ability to undergo megakaryocytic (MK) differentiation. SIRT1 was required for commitment to the MK lineage and subsequent maturation, but was not directly involved in polyploidization of either K562 cells or an already-MK-committed cell line, CHRF-288-11. The observed blockage in commitment to the MK lineage was associated with a dramatic decrease in the formation of autophagic vacuoles, which was previously shown to be required for K562 cell MK commitment. Autophagy-associated conversion of the protein LC3-I to LC3-II was greatly enhanced by overexpression of wildtype SIRT1, further suggesting a functional connection between SIRT1, autophagy, and MK differentiation. Based on its clear effects on autophagy, we also examined the effect of SIRT1 modulation on stress responses. Consistent

  8. Coconut oil protects cortical neurons from amyloid beta toxicity by enhancing signaling of cell survival pathways.

    Science.gov (United States)

    Nafar, F; Clarke, J P; Mearow, K M

    2017-01-23

    Alzheimer's disease is a progressive neurodegenerative disease that has links with other conditions that can often be modified by dietary and life-style interventions. In particular, coconut oil has received attention as having potentially having benefits in lessening the cognitive deficits associated with Alzheimer's disease. In a recent report, we showed that neuron survival in cultures co-treated with coconut oil and Aβ was rescued compared to cultures exposed only to Aβ. Here we investigated treatment with Aβ for 1, 6 or 24 h followed by addition of coconut oil for a further 24 h, or treatment with coconut oil for 24 h followed by Aβ exposure for various periods. Neuronal survival and several cellular parameters (cleaved caspase 3, synaptophysin labeling and ROS) were assessed. In addition, the influence of these treatments on relevant signaling pathways was investigated with Western blotting. In terms of the treatment timing, our data indicated that coconut oil rescues cells pre-exposed to Aβ for 1 or 6 h, but is less effective when the pre-exposure has been 24 h. However, pretreatment with coconut oil prior to Aβ exposure showed the best outcomes. Treatment with octanoic or lauric acid also provided protection against Aβ, but was not as effective as the complete oil. The coconut oil treatment reduced the number of cells with cleaved caspase and ROS labeling, as well as rescuing the loss of synaptophysin labeling observed with Aβ treatment. Treatment with coconut oil, as well as octanoic, decanoic and lauric acids, resulted in a modest increase in ketone bodies compared to controls. The biochemical data suggest that Akt and ERK activation may contribute to the survival promoting influence of coconut oil. This was supported by observations that a PI3-Kinase inhibitor blocked the rescue effect of CoOil on Aβ amyloid toxicity. Further studies into the mechanisms of action of coconut oil and its constituent medium chain fatty acids are warranted.

  9. Inactivation of the forkhead transcription factor FoxO3 is essential for PKB-mediated survival of hematopoietic progenitor cells by kit ligand

    DEFF Research Database (Denmark)

    Engström, Maria; Karlsson, Richard; Jönsson, Jan-Ingvar

    2003-01-01

    OBJECTIVE: Kit ligand (KL) is a major survival factor for hematopoietic stem cells. Although anti-apoptotic bcl-2 family members are expressed in these cells, the survival effects by KL appear to involve other mechanisms. Survival signals can also be elicited by the activation of phosphatidylinos......OBJECTIVE: Kit ligand (KL) is a major survival factor for hematopoietic stem cells. Although anti-apoptotic bcl-2 family members are expressed in these cells, the survival effects by KL appear to involve other mechanisms. Survival signals can also be elicited by the activation...... of hematopoietic progenitors. Because forkhead proteins are involved in controlling apoptosis and cell-cycle progression, this may be one important mechanism by which survival of hematopoietic progenitors is mediated....

  10. Coordinating Etk/Bmx activation and VEGF upregulation to promote cell survival and proliferation.

    Science.gov (United States)

    Chau, Cindy H; Chen, Kai-Yun; Deng, Hong-Tao; Kim, Kwang-Jin; Hosoya, Ken-ichi; Terasaki, Tetsuya; Shih, Hsiu-Ming; Ann, David K

    2002-12-12

    Etk/Bmx, a member of the Tec family of non-receptor tyrosine kinase, is characterized by an N-terminal PH domain and has recently been shown to be involved in the regulation of various cellular processes, including proliferation, differentiation, motility and apoptosis. Since VEGF and the activation of its signaling pathway have been implicated in modulating a variety of biological responses, we characterized the role of Etk-dependent signaling pathways involved in the upregulation of VEGF expression, and explored the functional implications of this enhancement in sustaining cell proliferation and survival. Using Northern and Western analyses, transient transfections, and pharmacological agents, we demonstrate that Etk activation alone is sufficient to transcriptionally induce VEGF expression, independent of the previously identified hypoxia response element (HRE), in both Pa-4 epithelial and TR-BBB endothelial cells under normoxia. In addition, Etk utilizes both MEK/ERK and PI3-K/Pak1 signaling pathways in concert to activate VEGF transcription. Functionally, Etk activation elicits a profound stimulatory effect on TR-BBB cell proliferation and formation of capillary-like networks in Matrigel containing reduced levels of growth factors. Finally, antisense oligonucleotides against either endogenous VEGF or Etk abrogate the proliferation of Etk-activated TR-BBB cells, and exogenous VEGF treatment stimulates endogenous Etk tyrosine phosphorylation in HUVECs. Taken together, these results indicate that VEGF is both an Etk downstream target gene and an Etk upstream activator, constituting a reciprocal Etk-VEGF autoregulatory loop. These findings, to our knowledge, are the first delineation of a network of positive feedforward signaling pathways that converge on the Etk-VEGF axis, causally associating Etk-mediation of VEGF induction with enhanced cellular processes in both epithelial and endothelial cells.

  11. The Bmi-1 polycomb protein antagonizes the (-)-epigallocatechin-3-gallate-dependent suppression of skin cancer cell survival.

    Science.gov (United States)

    Balasubramanian, Sivaprakasam; Adhikary, Gautam; Eckert, Richard L

    2010-03-01

    The polycomb group (PcG) proteins are epigenetic regulators of gene expression that enhance cell survival. This regulation is achieved via action of two multiprotein PcG complexes--PRC2 (EED) and PRC1 [B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1)]. These complexes modulate gene expression by increasing histone methylation and reducing acetylation--leading to a closed chromatin conformation. Activity of these proteins is associated with increased cell proliferation and survival. We show increased expression of key PcG proteins in immortalized keratinocytes and skin cancer cell lines. We examine the role of two key PcG proteins, Bmi-1 and enhancer of zeste homolog 2 (Ezh2), and the impact of the active agent in green tea, (-)-epigallocatechin-3-gallate (EGCG), on the function of these regulators. EGCG treatment of SCC-13 cells reduces Bmi-1 and Ezh2 level and this is associated with reduced cell survival. The reduction in survival is associated with a global reduction in histone H3 lysine 27 trimethylation, a hallmark of PRC2 complex action. This change in PcG protein expression is associated with reduced expression of key proteins that enhance progression through the cell cycle [cyclin-dependent kinase (cdk)1, cdk2, cdk4, cyclin D1, cyclin E, cyclin A and cyclin B1] and increased expression of proteins that inhibit cell cycle progression (p21 and p27). Apoptosis is also enhanced, as evidenced by increased caspase 9, 8 and 3 cleavage and increased poly(adenosine diphosphate ribose) polymerase cleavage. EGCG treatment also increases Bax and suppresses Bcl-xL expression. Vector-mediated enhanced Bmi-1 expression reverses these EGCG-dependent changes. These findings suggest that green tea polyphenols reduce skin tumor cell survival by influencing PcG-mediated epigenetic regulatory mechanisms.

  12. Conserved BK channel-protein interactions reveal signals relevant to cell death and survival.

    Directory of Open Access Journals (Sweden)

    Bernd Sokolowski

    Full Text Available The large-conductance Ca(2+-activated K(+ (BK channel and its β-subunit underlie tuning in non-mammalian sensory or hair cells, whereas in mammals its function is less clear. To gain insights into species differences and to reveal putative BK functions, we undertook a systems analysis of BK and BK-Associated Proteins (BKAPS in the chicken cochlea and compared these results to other species. We identified 110 putative partners from cytoplasmic and membrane/cytoskeletal fractions, using a combination of coimmunoprecipitation, 2-D gel, and LC-MS/MS. Partners included 14-3-3γ, valosin-containing protein (VCP, stathmin (STMN, cortactin (CTTN, and prohibitin (PHB, of which 16 partners were verified by reciprocal coimmunoprecipitation. Bioinformatics revealed binary partners, the resultant interactome, subcellular localization, and cellular processes. The interactome contained 193 proteins involved in 190 binary interactions in subcellular compartments such as the ER, mitochondria, and nucleus. Comparisons with mice showed shared hub proteins that included N-methyl-D-aspartate receptor (NMDAR and ATP-synthase. Ortholog analyses across six species revealed conserved interactions involving apoptosis, Ca(2+ binding, and trafficking, in chicks, mice, and humans. Functional studies using recombinant BK and RNAi in a heterologous expression system revealed that proteins important to cell death/survival, such as annexinA5, γ-actin, lamin, superoxide dismutase, and VCP, caused a decrease in BK expression. This revelation led to an examination of specific kinases and their effectors relevant to cell viability. Sequence analyses of the BK C-terminus across 10 species showed putative binding sites for 14-3-3, RAC-α serine/threonine-protein kinase 1 (Akt, glycogen synthase kinase-3β (GSK3β and phosphoinositide-dependent kinase-1 (PDK1. Knockdown of 14-3-3 and Akt caused an increase in BK expression, whereas silencing of GSK3β and PDK1 had the opposite

  13. Hydrostatic pressure does not cause detectable changes in survival of human retinal ganglion cells.

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    Andrew Osborne

    Full Text Available PURPOSE: Elevated intraocular pressure (IOP is a major risk factor for glaucoma. One consequence of raised IOP is that ocular tissues are subjected to increased hydrostatic pressure (HP. The effect of raised HP on stress pathway signaling and retinal ganglion cell (RGC survival in the human retina was investigated. METHODS: A chamber was designed to expose cells to increased HP (constant and fluctuating. Accurate pressure control (10-100 mmHg was achieved using mass flow controllers. Human organotypic retinal cultures (HORCs from donor eyes (<24 h post mortem were cultured in serum-free DMEM/HamF12. Increased HP was compared to simulated ischemia (oxygen glucose deprivation, OGD. Cell death and apoptosis were measured by LDH and TUNEL assays, RGC marker expression by qRT-PCR (THY-1 and RGC number by immunohistochemistry (NeuN. Activated p38 and JNK were detected by Western blot. RESULTS: Exposure of HORCs to constant (60 mmHg or fluctuating (10-100 mmHg; 1 cycle/min pressure for 24 or 48 h caused no loss of structural integrity, LDH release, decrease in RGC marker expression (THY-1 or loss of RGCs compared with controls. In addition, there was no increase in TUNEL-positive NeuN-labelled cells at either time-point indicating no increase in apoptosis of RGCs. OGD increased apoptosis, reduced RGC marker expression and RGC number and caused elevated LDH release at 24 h. p38 and JNK phosphorylation remained unchanged in HORCs exposed to fluctuating pressure (10-100 mmHg; 1 cycle/min for 15, 30, 60 and 90 min durations, whereas OGD (3 h increased activation of p38 and JNK, remaining elevated for 90 min post-OGD. CONCLUSIONS: Directly applied HP had no detectable impact on RGC survival and stress-signalling in HORCs. Simulated ischemia, however, activated stress pathways and caused RGC death. These results show that direct HP does not cause degeneration of RGCs in the ex vivo human retina.

  14. Piperlongumine inhibits the proliferation and survival of B-cell acute lymphoblastic leukemia cell lines irrespective of glucocorticoid resistance

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seong-Su, E-mail: seong-su-han@uiowa.edu [Division of Pediatric Hematology-Oncology, University of Iowa Carver College of Medicine, Iowa City, IA (United States); Han, Sangwoo [Health and Human Physiology, University of Iowa Carver College of Medicine, Iowa City, IA (United States); Kamberos, Natalie L. [Division of Pediatric Hematology-Oncology, University of Iowa Carver College of Medicine, Iowa City, IA (United States)

    2014-09-26

    Highlights: • PL inhibits the proliferation of B-ALL cell lines irrespective of GC-resistance. • PL selectively kills B-ALL cells by increasing ROS, but not normal counterpart. • PL does not sensitize majority of B-ALL cells to DEX. • PL represses the network of constitutively activated TFs and modulates their target genes. • PL may serve as a new therapeutic molecule for GC-resistant B-ALL. - Abstract: Piperlongumine (PL), a pepper plant alkaloid from Piper longum, has anti-inflammatory and anti-cancer properties. PL selectively kills both solid and hematologic cancer cells, but not normal counterparts. Here we evaluated the effect of PL on the proliferation and survival of B-cell acute lymphoblastic leukemia (B-ALL), including glucocorticoid (GC)-resistant B-ALL. Regardless of GC-resistance, PL inhibited the proliferation of all B-ALL cell lines, but not normal B cells, in a dose- and time-dependent manner and induced apoptosis via elevation of ROS. Interestingly, PL did not sensitize most of B-ALL cell lines to dexamethasone (DEX). Only UoC-B1 exhibited a weak synergistic effect between PL and DEX. All B-ALL cell lines tested exhibited constitutive activation of multiple transcription factors (TFs), including AP-1, MYC, NF-κB, SP1, STAT1, STAT3, STAT6 and YY1. Treatment of the B-ALL cells with PL significantly downregulated these TFs and modulated their target genes. While activation of AURKB, BIRC5, E2F1, and MYB mRNA levels were significantly downregulated by PL, but SOX4 and XBP levels were increased by PL. Intriguingly, PL also increased the expression of p21 in B-ALL cells through a p53-independent mechanism. Given that these TFs and their target genes play critical roles in a variety of hematological malignancies, our findings provide a strong preclinical rationale for considering PL as a new therapeutic agent for the treatment of B-cell malignancies, including B-ALL and GC-resistant B-ALL.

  15. High-mobility group box protein 1 promotes the survival of myeloid-derived suppressor cells by inducing autophagy.

    Science.gov (United States)

    Parker, Katherine H; Horn, Lucas A; Ostrand-Rosenberg, Suzanne

    2016-09-01

    Myeloid-derived suppressor cells are immune-suppressive cells that are elevated in most individuals with cancer, where their accumulation and suppressive activity are driven by inflammation. As myeloid-derived suppressor cells inhibit anti-tumor immunity and promote tumor progression, we are determining how their viability is regulated. Previous studies have established that the damage-associated molecular pattern molecule high-mobility group box protein 1 drives myeloid-derived suppressor cell accumulation and suppressive potency and is ubiquitously present in the tumor microenvironment. As high-mobility group box protein 1 also facilitates tumor cell survival by inducing autophagy, we sought to determine if high-mobility group box protein 1 regulates myeloid-derived suppressor cell survival through induction of autophagy. Inhibition of autophagy increased the quantity of apoptotic myeloid-derived suppressor cells, demonstrating that autophagy extends the survival and increases the viability of myeloid-derived suppressor cells. Inhibition of high-mobility group box protein 1 similarly increased the level of apoptotic myeloid-derived suppressor cells and reduced myeloid-derived suppressor cell autophagy, demonstrating that in addition to inducing the accumulation of myeloid-derived suppressor cells, high-mobility group box protein 1 sustains myeloid-derived suppressor cell viability. Circulating myeloid-derived suppressor cells have a default autophagic phenotype, and tumor-infiltrating myeloid-derived suppressor cells are more autophagic, consistent with the concept that inflammatory and hypoxic conditions within the microenvironment of solid tumors contribute to tumor progression by enhancing immune-suppressive myeloid-derived suppressor cells. Overall, these results demonstrate that in addition to previously recognized protumor effects, high-mobility group box protein 1 contributes to tumor progression by increasing myeloid-derived suppressor cell viability by

  16. Signal transducer and activator of transcription 3 activation is associated with bladder cancer cell growth and survival

    Directory of Open Access Journals (Sweden)

    Hsieh Fu-Chuan

    2008-10-01

    Full Text Available Abstract Background Constitutive activation of signal transducer and activator of transcription 3 (Stat3 signaling pathway plays an important role in several human cancers. Activation of Stat3 is dependent on the phosphorylation at the tyrosine residue 705 by upstream kinases and subsequent nuclear translocation after dimerization. It remains unclear whether oncogenic Stat3 signaling pathway is involved in the oncogenesis of bladder cancer. Results We found that elevated Stat3 phosphorylation in 19 of 100 (19% bladder cancer tissues as well as bladder cancer cell lines, WH, UMUC-3 and 253J. To explore whether Stat3 activation is associated with cell growth and survival of bladder cancer, we targeted the Stat3 signaling pathway in bladder cancer cells using an adenovirus-mediated dominant-negative Stat3 (Y705F and a small molecule compound, STA-21. Both prohibited cell growth and induction of apoptosis in these bladder cancer cell lines but not in normal bladder smooth muscle cell (BdSMC. The survival inhibition might be mediated through apoptotic caspase 3, 8 and 9 pathways. Moreover, down-regulation of anti-apoptotic genes (Bcl-2, Bcl-xL and survivin and a cell cycle regulating gene (cyclin D1 was associated with the cell growth inhibition and apoptosis. Conclusion These results indicated that activation of Stat3 is crucial for bladder cancer cell growth and survival. Therefore, interference of Stat3 signaling pathway emerges as a potential therapeutic approach for bladder cancer.

  17. The P2X7 receptor regulates cell survival, migration and invasion of pancreatic ductal adenocarcinoma cells

    DEFF Research Database (Denmark)

    Giannuzzo, Andrea; Pedersen, Stine Helene Falsig; Novak, Ivana

    2015-01-01

    BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is presently one of the cancers with the worst survival rates and least effective treatments. Moreover, total deaths due to PDAC are predicted to increase in the next 15 years. Therefore, novel insights into basic mechanism of PDAC development...... and therapies are needed. PDAC is characterized by a complex microenvironment, in which cancer and stromal cells release different molecules, such as ATP. ATP can be transported and/or exocytosed from active cancer cells and released from dying cells in the necrotic core of the cancer. We hypothesized that one...... of the ATP receptors, the P2X7 receptor (P2X7R) could be an important player in PDAC behaviour. METHODS: We determined the expression (real time PCR and Western blot) and localization (immunofluorescence) of P2X7R in human PDAC cell lines (AsPC-1, BxPC-3, Capan-1, MiaPaCa-2, Panc-1) and a "normal" human...

  18. Acrolein activates cell survival and apoptotic death responses involving the endoplasmic reticulum in A549 lung cells.

    Science.gov (United States)

    Tanel, André; Pallepati, Pragathi; Bettaieb, Ahmed; Morin, Patrick; Averill-Bates, Diana A

    2014-05-01

    Acrolein, a highly reactive α,β-unsaturated aldehyde, is a product of endogenous lipid peroxidation. It is a ubiquitous environmental pollutant that is generated mainly by smoke, overheated cooking oil and vehicle exhaust. Acrolein damages cellular proteins, which could lead to accumulation of aberrantly-folded proteins in the endoplasmic reticulum (ER). This study determines the mechanisms involved in acrolein-induced apoptosis mediated by the ER and possible links with the ER stress response in human A549 lung cells. The exposure of cells to acrolein (15-50μM) for shorter times of 15 to 30min activated several ER stress markers. These included the ER chaperone protein BiP and the three ER sensors: (i) the survival/rescue molecules protein kinase RNA (PKR)-like ER kinase (PERK) and eukaryotic initiation factor 2 alpha (eIF2α) were phosphorylated; (ii) cleavage of activating transcription factor 6 (ATF6) occurred, and (iii) inositol-requiring protein-1 alpha (IRE1α) was phosphorylated. Acrolein (25-50μM) caused apoptotic cell death mediated by the ER after 2h, which was characterised by the induction of CHOP and activation of ER proteases calpain and caspase-4. Calpain and caspase-7 were the initiating factors for caspase-4 activation in acrolein-induced apoptosis. These results increase our knowledge about cellular responses to acrolein in lung cells, which have implications for human health.

  19. Gene expression profile correlates with T cell infiltration and relative survival in glioblastoma patients vaccinated with dendritic cell immunotherapy

    Science.gov (United States)

    Prins, Robert M.; Soto, Horacio; Konkankit, Vera; Odesa, Sylvia K.; Eskin, Ascia; Yong, William H.; Nelson, Stanley F.; Liau, Linda M.

    2010-01-01

    Purpose To assess the feasibility, safety, and toxicity of autologous tumor lysate-pulsed dendritic cell (DC) vaccination and toll-like receptor (TLR) agonists in patients with newly diagnosed and recurrent glioblastoma. Clinical and immune responses were monitored and correlated with tumor gene expression profiles. Experimental Design Twenty-three patients with glioblastoma (WHO grade IV) were enrolled in this dose-escalation study and received three biweekly injections of glioma lysate-pulsed DCs followed by booster vaccinations with either imiquimod or poly-ICLC adjuvant every three months until tumor progression. Gene expression profiling, IHC, FACS, and cytokine bead arrays were performed on patient tumors and PBMC. Results DC vaccinations are safe and not associated with any dose-limiting toxicity. The median overall survival from the time of initial surgical diagnosis of glioblastoma was 31.4 months, with a one-, two-, and three-year survival rate of 91%, 55% and 47%, respectively. Patients whose tumors had mesenchymal gene expression signatures exhibited increased survival following DC vaccination compared to historical controls of the same genetic subtype. Tumor samples with a mesenchymal gene expression signature had a higher number of CD3+ and CD8+ tumor infiltrating lymphocytes (TILs) compared with glioblastomas of other gene expression signatures (p = 0.006). Conclusion Autologous tumor lysate-pulsed DC vaccination in conjunction with TLR agonists is safe as adjuvant therapy in newly diagnosed and recurrent glioblastoma patients. Our results suggest that the mesenchymal gene expression profile may identify an immunogenic subgroup of glioblastoma that may be more responsive to immune-based therapies. PMID:21135147

  20. Heterogeneous X-ray survival characteristics of lymphocytes in prolymphocytic leukaemia. Mathematical analysis distinguishing delayed cell death and true radioresistance

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, A.E.R.; O' Connor, T.W.E.; Slater, N.G.P. (Division of Haematology, United Medical and Dental Schools of Guy' s and St. Thomas' Hospitals, London (United Kingdom)); Peel, W.E. (Computing Services, Manchester Metropolitan University, Manchester (United Kingdom))

    1994-10-01

    The survival of non-dividing (G[sub 0]) leukaemic lymphocytes in culture is generally too short for their radiosensitivity to be quantitatively assessed, since lethally X-irradiated cells may show a long delay before manifestations of cell death ('interphase death') are seen. Counts of surviving cells well therefore include both lethally-hit cells (apparent survivors), and real survivors which have not been lethally hit. Death rates of irradiated leukaemic and normal cells show great variation between individuals, so that comparisons of radiosensitivity between different cell populations based on surviving cell counts at a single time-point are invalid. In this study the supposed radioresistance of prolymphocytic leukaemia lymphocytes was examined in 6 patients with B-cell disease. Survival curves were plotted from serial observations made over several days after graded X-irradiation (0-1000 cGy). We attempted to interpret these radiation responses in terms of their dose dependence (intrinsic radiosensitivity) and time dependence (cell death rate) characteristics using the best-fitting of four mathematical models, all based on classical 'single-hit' target theory. The apparent radioresistance shown in 4 cases could be explained by very slow death rates (T[sub 172] values 55-205 h) of cells proving otherwise radiosensitive (D37 values 38-123 cGy). Genuine radioresistance was found in only 1 case (actual D37 value above 2000 cGy). B ignoring delayed cell death in clinical assessments, pathological lymphocytes could be mistakenly categorized as resistant to elimination by radiotherapy. (au) (30 refs.).

  1. ALS/FTLD-linked TDP-43 regulates neurite morphology and cell survival in differentiated neurons

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jeong-Ho; Yu, Tae-Hoon; Ryu, Hyun-Hee; Jun, Mi-Hee; Ban, Byung-Kwan [Department of Biotechnology, College of Life Science and Nanotechnology, Hannam University, Dajeon 305-811 (Korea, Republic of); Jang, Deok-Jin [Department of Applied Biology, College of Ecology and Environment, Kyungpook National University, 386, Gajang-dong, Sangju-si, Kyungbuk 742-711 (Korea, Republic of); Lee, Jin-A, E-mail: leeja@hnu.kr [Department of Biotechnology, College of Life Science and Nanotechnology, Hannam University, Dajeon 305-811 (Korea, Republic of)

    2013-08-01

    Tar-DNA binding protein of 43 kDa (TDP-43) has been characterized as a major component of protein aggregates in brains with neurodegenerative diseases such as frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). However, physiological roles of TDP-43 and early cellular pathogenic effects caused by disease associated mutations in differentiated neurons are still largely unknown. Here, we investigated the physiological roles of TDP-43 and the effects of missense mutations associated with diseases in differentiated cortical neurons. The reduction of TDP-43 by siRNA increased abnormal neurites and decreased cell viability. ALS/FTLD-associated missense mutant proteins (A315T, Q331K, and M337V) were partially mislocalized to the cytosol and neurites when compared to wild-type and showed abnormal neurites similar to those observed in cases of loss of TDP-43. Interestingly, cytosolic expression of wild-type TDP-43 with mutated nuclear localization signals also induced abnormal neurtie morphology and reduction of cell viability. However, there was no significant difference in the effects of cytosolic expression in neuronal morphology and cell toxicity between wild-type and missense mutant proteins. Thus, our results suggest that mislocalization of missense mutant TDP-43 may contribute to loss of TDP-43 function and affect neuronal morphology, probably via dominant negative action before severe neurodegeneration in differentiated cortical neurons. Highlights: • The function of nuclear TDP-43 in neurite morphology in mature neurons. • Partial mislocalization of TDP-43 missense mutants into cytosol from nucleus. • Abnormal neurite morphology caused by missense mutants of TDP-43. • The effect of cytosolic expression of TDP-43 in neurite morphology and in cell survival.

  2. Food matrices and cell conditions influence survival of Lactobacillus rhamnosus GG under heat stresses and during storage.

    Science.gov (United States)

    Endo, Akihito; Teräsjärvi, Johanna; Salminen, Seppo

    2014-03-17

    The present study evaluated impact of moisture content and cell conditions on survival of probiotic strain, Lactobacillus rhamnosus GG, under lethal heat stresses and during long-term storage using freeze-dried cells and oils as matrices. Viable cell counts of freeze-dried L. rhamnosus GG cells suspended in oils had only 1-log-reduction after 5min at 80°C and approximately 3-log-reduction after 20min, while no or very few viable cells were recorded for freeze dried cells suspended in buffer and cultured cells in oils. Surprisingly, freeze-dried cells suspended in oils still contained 4.3 to 6.7logCFU/ml after 5min at 95°C. Long-term storage study indicated that freeze-dried cells suspended in oils kept viable conditions for 4months, and a loss of the viability was only 0.3 to 0.6logCFU/ml. Viable cell counts of cultured cells suspended in oils were not present after 3days to 3months. These results clearly indicate that moisture and cell conditions have a great impact on survival of probiotics under severe heat stress in processing and during long-term storage. Combination of freeze-dried cells and oils as carrier provides beneficial options to preserve viability of probiotics in food processes and storage.

  3. Multiple MTS Assay as the Alternative Method to Determine Survival Fraction of the Irradiated HT-29 Colon Cancer Cells.

    Science.gov (United States)

    Arab-Bafrani, Zahra; Shahbazi-Gahrouei, Daryoush; Abbasian, Mahdi; Fesharaki, Mehrafarin

    2016-01-01

    A multiple colorimetric assay has been introduced to evaluate the proliferation and determination of survival fraction (SF) of irradiated cells. The estimation of SF based on the cell-growth curve information is the major advantage of this assay. In this study, the utility of multiple-MTS assay for the SF estimation of irradiated HT-29 colon cancer cells, which were plated before irradiation, was evaluated. The SF of HT-29 colon cancer cells under irradiation with 9 MV photon was estimated using multiple-MTS assay and colony assay. Finally, the correlation between two assays was evaluated. Results showed that there are no significant differences between the SF obtained by two assays at different radiation doses (P > 0.05), and the survival curves have quite similar trends. In conclusion, multiple MTS-assay can be a reliable method to determine the SF of irradiated colon cancer cells that plated before irradiation.

  4. Death and survival of neuronal and astrocytic cells in ischemic brain injury: a role of autophagy

    Institute of Scientific and Technical Information of China (English)

    Min XU; Hui-ling ZHANG

    2011-01-01

    Autophagy is a highly regulated cellular mechanism that leads to degradation of long-lived proteins and dysfunctional organelles. The process has been implicated in a variety of physiological and pathological conditions relevant to neurological diseases. Recent studies show the existence of autophagy in cerebral ischemia, but no consensus has yet been reached regarding the functions of autophagy in this condition. This article highlights the activation of autophagy during cerebral ischemia and/or reperfusion, especially in neurons and astrocytes, as well as the role of autophagy in neuronal or astrocytic cell death and survival. We propose that physiological levels of autophagy, presumably caused by mild to modest hypoxia or ischemia, appear to be protective. However, high levels of autophagy caused by severe hypoxia or ischemia and/or reperfusion may cause self-digestion and eventual neuronal and astrocytic cell death. We also discuss that oxidative and endoplasmic reticulum (ER) stresses in cerebral hypoxia or ischemia and/or reperfusion are potent stimuli of autophagy in neurons and astrocytes. In addition, we review the evidence suggesting a considerable overlap between autophagy on one hand, and apoptosis, necrosis and necroptosis on the other hand, in determining the outcomes and final morphology of damaged neurons and astrocytes.

  5. Biofilm-grown Burkholderia cepacia complex cells survive antibiotic treatment by avoiding production of reactive oxygen species.

    Directory of Open Access Journals (Sweden)

    Heleen Van Acker

    Full Text Available The presence of persister cells has been proposed as a factor in biofilm resilience. In the present study we investigated whether persister cells are present in Burkholderia cepacia complex (Bcc biofilms, what the molecular basis of antimicrobial tolerance in Bcc persisters is, and how persisters can be eradicated from Bcc biofilms. After treatment of Bcc biofilms with high concentrations of various antibiotics often a small subpopulation survived. To investigate the molecular mechanism of tolerance in this subpopulation, Burkholderia cenocepacia biofilms were treated with 1024 µg/ml of tobramycin. Using ROS-specific staining and flow cytometry, we showed that tobramycin increased ROS production in treated sessile cells. However, approximately 0.1% of all sessile cells survived the treatment. A transcriptome analysis showed that several genes from the tricarboxylic acid cycle and genes involved in the electron transport chain were downregulated. In contrast, genes from the glyoxylate shunt were upregulated. These data indicate that protection against ROS is important for the survival of persisters. To confirm this, we determined the number of persisters in biofilms formed by catalase mutants. The persister fraction in ΔkatA and ΔkatB biofilms was significantly reduced, confirming the role of ROS detoxification in persister survival. Pretreatment of B. cenocepacia biofilms with itaconate, an inhibitor of isocitrate lyase (ICL, the first enzyme in the glyoxylate shunt, reduced the persister fraction approx. 10-fold when the biofilms were subsequently treated with tobramycin. In conclusion, most Bcc biofilms contain a significant fraction of persisters that survive treatment with high doses of tobramycin. The surviving persister cells downregulate the TCA cycle to avoid production of ROS and at the same time activate an alternative pathway, the glyoxylate shunt. This pathway may present a novel target for combination therapy.

  6. High-efficiency transfection and survival rates of embryonic and adult mouse neural stem cells achieved by electroporation.

    Science.gov (United States)

    Bertram, Bettina; Wiese, Stefan; von Holst, Alexander

    2012-08-15

    Cells of the central nervous system are notoriously difficult to transfect. This is not only true for neurons and glial cells but also for dividing neural stem and progenitor cells (NSCs). About ten years ago a major advance was provided by introduction of the nucleofection technology that allowed for transfection of approximately half of the exposed NSCs. However, limitations were encountered with the need for large numbers of NSCs for a single transfection and compromised survival rates with typically only one-third of the cells surviving the pulse conditions. Here, we report the establishment of a pulse protocol that targets NSCs with high efficiency and twofold higher NSC survival rates using the 4D Nucleofector device. We demonstrate that the established protocol not only provides a clear and significant improvement over existing protocols with transfection rates above 80% and two-thirds of the NSCs surviving for at least 48h, but also their unaltered differentiation along neuronal and glial lineages. This improved protocol for the transfection of sensitive mouse central nervous system derived cells will provide an important step forward for studies of gene function by overexpression or knock-down of genes in cultured NSCs.

  7. Substitued (E-b-(benzoylacrylic acids suppressed survival of neoplastic human HeLa cells

    Directory of Open Access Journals (Sweden)

    I. JURANIC

    1999-09-01

    Full Text Available The bacteriostatic activity of some of alkyl substituted (E-b-(benzoylacrylic acids was shown earlier. The aim of this study was to investigate the antiproliferative action of 19 alkyl-, or halogeno-, or methoxy-, or acetamido- substituted (E-b-(benzoylacrylic acids, against human cervix carcinoma, HeLa, cells. Target HeLa cells were continuously treated with increasing concentrations of substituted (E-b-(benzoylacrylic acids during two days. The MTT test was used for assessment of the antiproliferative action of this group of compounds. Treatment of HeLa cells with 4-methyl-, 4-fluoro-, 4-chloro-, 4-bromo- and 4-methoxy- derivatives of (E-b-(benzoyl acrylic acid leads to the expression of cytostatic activity against HeLa cells (IC50 were in the range from 31-40 µM. Their antiproliferative action was less than that of the basic compound (E-b-(benzoylacrylic acid whose IC50 was 28.5 µM. The 3,4-dimethyl-, 2,4-dimethyl- and 2,5-dimethyl- derivatives as well as the 4-ethyl- and 3,4-dichloro- and 2,4-dichloro-derivatives, have stronger cytostatic activity than the correspoding monosubstituted and parent compound. Their IC50 were 18.5 µM; 17.5 µM; 17.0 mM; 17.5 µM; 22.0 µM and 18 µM, respectively. The 4-iso-propyl- and 4-n-butyl-derivatives exerted higher cytostatic activity than the compounds with a lower number of methylene -CH2- groups in the substitutent. Their IC50 were 14.5 µM and 6.5 µM respectively. The 2,5-di-iso-propyl- and 4-tert-butyl-derivatives expressed the most strong antiproliferative action against the investigated HeLa cells, IC50 being 4.5 µM and 5.5 µM, respectively. The investigated compounds affected the survival of HeLa cells, expressing a strong structure-activity relationship of the Hansch type.

  8. Glycogen synthase kinase 3 beta positively regulates Notch signaling in vascular smooth muscle cells: role in cell proliferation and survival.

    Science.gov (United States)

    Guha, Shaunta; Cullen, John P; Morrow, David; Colombo, Alberto; Lally, Caitríona; Walls, Dermot; Redmond, Eileen M; Cahill, Paul A

    2011-09-01

    The role of glycogen synthase kinase 3 beta (GSK-3β) in modulating Notch control of vascular smooth muscle cell (vSMC) growth (proliferation and apoptosis) was examined in vitro under varying conditions of cyclic strain and validated in vivo following changes in medial tension and stress. Modulation of GSK-3β in vSMC following ectopic expression of constitutively active GSK-3β, siRNA knockdown and pharmacological inhibition with SB-216763 demonstrated that GSK-3β positively regulates Notch intracellular domain expression, CBF-1/RBP-Jκ transactivation and downstream target gene mRNA levels, while concomitantly promoting vSMC proliferation and inhibiting apoptosis. In contrast, inhibition of GSK-3β attenuated Notch signaling and decreased vSMC proliferation and survival. Exposure of vSMC to cyclic strain environments in vitro using both a Flexercell™ Tension system and a novel Sylgard™ phantom vessel following bare metal stent implantation revealed that cyclic strain inhibits GSK-3β activity independent of p42/p44 MAPK and p38 activation concomitant with reduced Notch signaling and decreased vSMC proliferation and survival. Exposure of vSMC to changes in medial strain microenvironments in vivo following carotid artery ligation revealed that enhanced GSK-3β activity was predominantly localized to medial and neointimal vSMC concomitant with increased Notch signaling, proliferating nuclear antigen and decreased Bax expression, respectively, as vascular remodeling progressed. GSK-3β is an important modulator of Notch signaling leading to altered vSMC cell growth where low strain/tension microenvironments prevail.

  9. The P2X7 receptor regulates cell survival, migration and invasion of pancreatic ductal adenocarcinoma cells

    DEFF Research Database (Denmark)

    Giannuzzo, Andrea; Pedersen, Stine Helene Falsig; Novak, Ivana

    2015-01-01

    BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is presently one of the cancers with the worst survival rates and least effective treatments. Moreover, total deaths due to PDAC are predicted to increase in the next 15 years. Therefore, novel insights into basic mechanism of PDAC development...... of the ATP receptors, the P2X7 receptor (P2X7R) could be an important player in PDAC behaviour. METHODS: We determined the expression (real time PCR and Western blot) and localization (immunofluorescence) of P2X7R in human PDAC cell lines (AsPC-1, BxPC-3, Capan-1, MiaPaCa-2, Panc-1) and a "normal" human...... pancreatic duct epithelial cell line (HPDE). The function of P2X7R in proliferation (BrdU assay), migration (wound assay) and invasion (Boyden chamber with matrigel) was characterized. Furthermore, we studied P2X7R-dependent pore formation (YoPro-1 assay) and cell death (caspase and annexin V / propidium...

  10. Inositol 1,4,5-trisphosphate 3-kinase B controls survival and prevents anergy in B cells.

    Science.gov (United States)

    Maréchal, Yoann; Quéant, Séverine; Polizzi, Selena; Pouillon, Valérie; Schurmans, Stéphane

    2011-01-01

    Inositol 1,4,5-trisphosphate 3-kinase B (or Itpkb) and inositol 1,3,4,5-tetrakisphosphate (Ins(1,3,4,5)P4), its reaction product, play an important role in the control of B lymphocyte fate and function in vivo. In order to investigate the fine mechanisms of Itpkb and Ins(1,3,4,5)P4 action in B cells, we crossed Itpkb(-/-) mice with transgenic mice expressing a 3-83μδ B cell receptor (BCR) specific for membrane-bound MHC-I H2-K(b) and H2-K(k) molecules. On a non-deleting H2-K(d) genetic background, we show that Itpkb is important for the control of Bim protein expression and B cell survival rather than for the control of B cell development from one stage to another. Analyses of cell surface markers expression, proapoptotic Bim protein expression, in vitro survival and in vivo turnover demonstrated that BCR transgenic Itpkb(-/-) B cells exhibit an anergic phenotype with the notable exception of their enhanced antigen-induced calcium signalling. On a deleting H2-K(b) genetic background, we show that Itpkb is not essential for BCR editing or negative selection. These data establish Itpkb as an important regulator of B cell survival and anergy in vivo.

  11. B-cell activation in cats with feline infectious peritonitis (FIP) by FIP-virus-induced B-cell differentiation/survival factors.

    Science.gov (United States)

    Takano, Tomomi; Azuma, Natsuko; Hashida, Yoshikiyo; Satoh, Ryoichi; Hohdatsu, Tsutomu

    2009-01-01

    It has been suggested that antibody overproduction plays a role in the pathogenesis of feline infectious peritonitis (FIP). However, only a few studies on the B-cell activation mechanism after FIP virus (FIPV) infection have been reported. The present study shows that: (1) the ratio of peripheral blood sIg(+) CD21(-) B-cells was higher in cats with FIP than in SPF cats, (2) the albumin-to-globulin ratio has negative correlation with the ratio of peripheral blood sIg(+) CD21(-) B-cell, (3) cells strongly expressing mRNA of the plasma cell master gene, B-lymphocyte-induced maturation protein 1 (Blimp-1), were increased in peripheral blood in cats with FIP, (4) mRNA expression of B-cell differentiation/survival factors, IL-6, CD40 ligand, and B-cell-activating factor belonging to the tumor necrosis factor family (BAFF), was enhanced in macrophages in cats with FIP, and (5) mRNAs of these B-cell differentiation/survival factors were overexpressed in antibody-dependent enhancement (ADE)-induced macrophages. These data suggest that virus-infected macrophages overproduce B-cell differentiation/survival factors, and these factors act on B-cells and promote B-cell differentiation into plasma cells in FIPV-infected cats.

  12. Inhibition of endogenous hydrogen sulfide production in clear-cell renal cell carcinoma cell lines and xenografts restricts their growth, survival and angiogenic potential.

    Science.gov (United States)

    Sonke, Eric; Verrydt, Megan; Postenka, Carl O; Pardhan, Siddika; Willie, Chantalle J; Mazzola, Clarisse R; Hammers, Matthew D; Pluth, Michael D; Lobb, Ian; Power, Nicholas E; Chambers, Ann F; Leong, Hon S; Sener, Alp

    2015-09-15

    Clear cell renal cell carcinoma (ccRCC) is characterized by Von Hippel-Lindau (VHL)-deficiency, resulting in pseudohypoxic, angiogenic and glycolytic tumours. Hydrogen sulfide (H2S) is an endogenously-produced gasotransmitter that accumulates under hypoxia and has been shown to be pro-angiogenic and cytoprotective in cancer. It was hypothesized that H2S levels are elevated in VHL-deficient ccRCC, contributing to survival, metabolism and angiogenesis. Using the H2S-specific probe MeRhoAz, it was found that H2S levels were higher in VHL-deficient ccRCC cell lines compared to cells with wild-type VHL. Inhibition of H2S-producing enzymes could reduce the proliferation, metabolism and survival of ccRCC cell lines, as determined by live-cell imaging, XTT/ATP assay, and flow cytometry respectively. Using the chorioallantoic membrane angiogenesis model, it was found that systemic inhibition of endogenous H2S production was able to decrease vascularization of VHL-deficient ccRCC xenografts. Endogenous H2S production is an attractive new target in ccRCC due to its involvement in multiple aspects of disease.

  13. Dennexin peptides modeled after the homophilic binding sites of the neural cell adhesion molecule (NCAM) promote neuronal survival, modify cell adhesion and impair spatial learning

    DEFF Research Database (Denmark)

    Køhler, Lene B; Christensen, Claus; Rossetti, Clara

    2010-01-01

    Neural cell adhesion molecule (NCAM)-mediated cell adhesion results in activation of intracellular signaling cascades that lead to cellular responses such as neurite outgrowth, neuronal survival, and modulation of synaptic activity associated with cognitive processes. The crystal structure...... between Ig1 and Ig3 and between Ig2 and Ig2, respectively, observed in the crystal structure. Although the two dennexin peptides differed in amino acid sequence, they both modulated cell adhesion, reflected by inhibition of NCAM-mediated neurite outgrowth. Both dennexins also promoted neuronal survival...

  14. Interactive effects involving different classes of excitatory amino acid receptors and the survival of cerebellar granule cells in culture

    DEFF Research Database (Denmark)

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

    1990-01-01

    Differentiating granule cells develop survival requirements in culture which can be met by treatment with high K+ or N-methyl-D-aspartate (NMDA) and, according to our recent findings, also with low concentrations of kainic acid (KA, 50 microM). We have now attempted to elucidate the mechanism(s) ...

  15. Enrichment of autologous fat grafts with ex-vivo expanded adipose tissue-derived stem cells for graft survival

    DEFF Research Database (Denmark)

    Kølle, Stig-Frederik Trojahn; Fischer-Nielsen, Anne; Mathiasen, Anders Bruun

    2013-01-01

    Autologous fat grafting is increasingly used in reconstructive surgery. However, resorption rates ranging from 25% to 80% have been reported. Therefore, methods to increase graft viability are needed. Here, we report the results of a triple-blind, placebo-controlled trial to compare the survival...... of fat grafts enriched with autologous adipose-derived stem cells (ASCs) versus non-enriched fat grafts....

  16. p70S6 kinase signals cell survival as well as growth, inactivating the pro-apoptotic molecule BAD

    DEFF Research Database (Denmark)

    Harada, H; Andersen, Jens S.; Mann, M;

    2001-01-01

    -specific phosphorylation of BAD, which inactivates this proapoptotic molecule. Rapamycin inhibited mitochondrial-based p70S6K, which prevented phosphorylation of Ser-136 on BAD and blocked cell survival induced by insulin-like growth factor 1 (IGF-1). Moreover, IGF-1-induced phosphorylation of BAD Ser-136 was abolished...

  17. Survival and migration of Schwann cells after the vascularized peripheral nerve grafted into spinal cord in rats

    Institute of Scientific and Technical Information of China (English)

    GUO Qing-shan; WANG Ai-min; WANG Xiao-jun; SUN Hong-zhen; DU Quan-yin

    2005-01-01

    Objective:To study the survival and ability of inducing axonal regeneration of the Schwann cells after the peripheral nerve being grafted into spinal cord. Methods:A total of 30 adult female Wistar rats were randomly divided into the VN (vascularized peripheral nerve) and PN (peripheral nerve) groups. A 5-mm spinal cord defect of the left posterior column was made at the T1-3 vertebral level. The defect was grafted with the vascularized or isolated peripheral nerve respectively. The survival and proliferation of the Schwann cells were assessed by histological and morphometric analysis 8 weeks after the operation. Results:In the VN group, the peripheral nerve grew into the cord with lots of Schwann cells survived and proliferated, and had more NF and S-100 positive fibers than in the PN group. Conclusion:The vascularized peripheral nerve enhances the survival and proliferation of the Schwann cells and prompts the regeneration of injured axon of the central nerve system to certain degree.

  18. Comparison of survival of chronic obstructive pulmonary disease patients with or without a localized non-small cell lung cancer

    DEFF Research Database (Denmark)

    Jeppesen, Stefan Starup; Gerner Hansen, Niels-Christian; Schytte, Tine

    2016-01-01

    OBJECTIVES: Chronic obstructive pulmonary disease (COPD) and non-small cell lung cancer (NSCLC) are often co-existing diseases with poor prognosis. The aim of this study was to compare survival in COPD patients with localized NSCLC treated with stereotactic body radiotherapy (NSCLC group) with COPD...

  19. Mitochondrial dysfunction in primary human fibroblasts triggers an adaptive cell survival program that requires AMPK-alpha

    NARCIS (Netherlands)

    Distelmaier, F.; Valsecchi, F.; Liemburg-Apers, D.C.; Lebiedzinska, M.; Rodenburg, R.J.T.; Heil, S.; Keijer, J.; Fransen, J.A.; Imamura, H.; Danhauser, K.; Seibt, A.; Viollet, B.; Gellerich, F.N.; Smeitink, J.; Wieckowski, M.R.; Willems, P.H.G.M.; Koopman, W.J.H.

    2015-01-01

    Dysfunction of complex I (CI) of the mitochondrial electron transport chain (ETC) features prominently in human pathology. Cell models of ETC dysfunction display adaptive survival responses that still are poorly understood but of relevance for therapy development. Here we comprehensively examined ho

  20. Mitochondrial dysfunction in primary human fibroblasts triggers an adaptive cell survival program that requires AMPK-α

    NARCIS (Netherlands)

    F. Distelmaier (Felix); F. Valsecchi (Federica); D.C. Liemburg-Apers (Dania C.); M. Lebiedzinska (Magdalena); R.J.T. Rodenburg (Richard); S.G. Heil (Sandra); J. Keijer (Jaap); J.A.M. Fransen (Jack); H. Imamura (Hiromi); K. Danhauser (Katharina); A. Seibt (Annette); B. Viollet (Benoit); F.N. Gellerich (Frank); J.A.M. Smeitink (Jan); M.R. Wieckowski (Mariusz R.); P.H.G.M. Willems (Peter H.G.M.); W.J.H. Koopman (W. J H)

    2015-01-01

    textabstractDysfunction of complex I (CI) of the mitochondrial electron transport chain (ETC) features prominently in human pathology. Cell models of ETC dysfunction display adaptive survival responses that still are poorly understood but of relevance for therapy development. Here we comprehensively

  1. Effect of inactive yeast cell wall on growth performance, survival rate and immune parameters in Pacific White Shrimp (Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Rutchanee Chotikachinda

    2008-10-01

    Full Text Available Effects of dietary inactive yeast cell wall on growth performance, survival rate, and immune parameters in pacific white shrimp (Litopenaeus vannamei was investigated. Three dosages of inactive yeast cell wall (0, 1, and 2 g kg-1 were tested in three replicate groups of juvenile shrimps with an average initial weight of 7.15±0.05 g for four weeks. There was no significant difference in final weight, survival rate, specific growth rate, feed conversion ratio, feed intake, protein efficiency ratio, and apparent net protein utilization of each treatments. However, different levels of inactive yeast cell wall showed an effect on certain immune parameters (p<0.05. Total hemocyte counts, granular hemocyte count, and bacterial clearance were better in shrimp fed diets supplemented with 1 and 2 g kg-1 inactive yeast cell wall as compared with thecontrol group.

  2. Errantum: Treatment of human astrocytoma U87 cells with silicon dioxide nanoparticles lowers their survival and alters their expression of mitochondrial and cell signaling proteins

    Directory of Open Access Journals (Sweden)

    Lai JCK

    2010-12-01

    Full Text Available Lai JCK, Ananthakrishnan G, Jandhyam S, et al. Treatment of human astrocytoma U87 cells with silicon dioxide nanoparticles lowers their survival and alters their expression of mitochondrial and cell signaling proteins. Int J Nanomedicine. 2010;5:715–723.The wrong image was used in Figure 5 on page 719.

  3. Association between genetic variations in tumor necrosis factor receptor genes and survival of patients with T-cell lymphoma

    Institute of Scientific and Technical Information of China (English)

    Kan Zhai; Jiang Chang; Chen Wu; Ning Lu; Li-Ming Huang; Tong-Wen Zhang; Dian-Ke Yu; Wen Tan; Dong-Xin Lin

    2012-01-01

    The prognosis of T-cell lymphoma (TCL) has been shown to be associated with the clinical characteristics of patients.However,there is little knowledge of whether genetic variations also affect the prognosis of TCL.This study investigated the associations between single nucleotide polymorphisms (SNPs) in tumor necrosis factor receptor superfamily (TNFRSF) genes and the survival of patients with TCL.A total of 38tag SNPs in 18 TNFRSF genes were genotyped using Sequenom platform in 150 patients with TCL.Kaplan-Meier survival estimates were plotted and significance was assessed using log-rank tests.Cox proportional hazard models were used to analyze each of these 38 SNPs with adjustment for covariates that might influence patient survival,including sex and international prognostic Index score.Hazard ratios (HRs) and their 95% confidence intervals (Cls) were calculated.Among the 38 SNPs tested,3 were significantly associated with the survival of patients with TCL.These SNPs were located at LTβR (rs3759333C>T) and TNFRSF17 (rs2017662C >T and rs2071336C>T).The 5-year survival rates were significantly different among patients carrying different genotypes and the HRs for death between the different genotypes ranged from 0.45 to 2.46.These findings suggest that the SNPs in TNFRSF genes might be important determinants for the survival of TCL patients.

  4. Tumour heterogeneity in non-small cell lung carcinoma assessed by CT texture analysis: a potential marker of survival

    Energy Technology Data Exchange (ETDEWEB)

    Ganeshan, Balaji; Miles, Ken [Brighton and Sussex Medical School, Clinical Imaging Sciences Centre, Division of Clinical and Laboratory Investigation, Brighton, East Sussex (United Kingdom); Panayiotou, Elleny; Burnand, Kate [Brighton and Sussex University Hospitals NHS Trust, Brighton (United Kingdom); Dizdarevic, Sabina [Brighton and Sussex University Hospitals NHS Trust, Department of Nuclear Medicine, Royal Sussex County Hospital, Brighton (United Kingdom)

    2012-04-15

    To establish the potential for tumour heterogeneity in non-small cell lung cancer (NSCLC) as assessed by CT texture analysis (CTTA) to provide an independent marker of survival for patients with NSCLC. Tumour heterogeneity was assessed by CTTA of unenhanced images of primary pulmonary lesions from 54 patients undergoing {sup 18}F-fluorodeoxyglucose (FDG) PET-CT for staging of NSCLC. CTTA comprised image filtration to extract fine, medium and coarse features with quantification of the distribution of pixel values (uniformity) within the filtered images. Receiver operating characteristics identified thresholds for PET and CTTA parameters that were related to patient survival using Kaplan-Meier analysis. The median (range) survival was 29.5 (1-38) months. 24, 10, 14 and 6 patients had tumour stages I, II, III and IV respectively. PET stage and tumour heterogeneity assessed by CTTA were significant independent predictors of survival (PET stage: Odds ratio 3.85, 95% confidence limits 0.9-8.09, P = 0.002; CTTA: Odds ratio 56.4, 95% confidence limits 4.79-666, p = 0.001). SUV was not a significantly associated with survival. Assessment of tumour heterogeneity by CTTA of non-contrast enhanced images has the potential for to provide a novel, independent predictor of survival for patients with NSCLC. (orig.)

  5. Rapamycin requires AMPK activity and p27 expression for promoting autophagy-dependent Tsc2-null cell survival.

    Science.gov (United States)

    Campos, Tania; Ziehe, Javiera; Fuentes-Villalobos, Francisco; Riquelme, Orlando; Peña, Daniela; Troncoso, Rodrigo; Lavandero, Sergio; Morin, Violeta; Pincheira, Roxana; Castro, Ariel F

    2016-06-01

    Tuberous sclerosis complex (TSC) disease results from inactivation of the TSC1 or TSC2 gene, and is characterized by benign tumors in several organs. Because TSC tumorigenesis correlates with hyperactivation of mTORC1, current therapies focus on mTORC1 inhibition with rapamycin or its analogs. Rapamycin-induced tumor shrinkage has been reported, but tumor recurrence occurs on withdrawal from rapamycin. Autophagy has been associated with development of TSC tumors and with tumor cell survival during rapamycin treatment. mTORC1 and AMPK directly inhibit and activate autophagy, respectively. AMPK is hyperactivated in TSC cells and tumors, and drives cytoplasmic sequestration of the cell-cycle inhibitor p27KIP (p27). Whether AMPK and p27 are involved in rapamycin-induced autophagy and survival of TSC cells remain unexplored. Here, we show that inhibition of AMPK by compound C or by shRNA-mediated depletion of LKB1 reduces activation of autophagy by rapamycin in Tsc2-null cells. Similarly, shRNA-mediated depletion of p27 inhibited rapamycin-induced autophagy. In support of p27 lying downstream of AMPK on the activation of autophagy in Tsc2-null cells, a p27 mutant that preferentially localizes in the cytosol recovered the effect of rapamycin on autophagy in both p27- and LKB1-depleted cells, but a nuclear p27 mutant was inactive. Finally, we show that p27-dependent activation of autophagy is involved in Tsc2-null cell survival under rapamycin treatment. These results indicate that an AMPK/p27 axis is promoting a survival mechanism that could explain in part the relapse of TSC tumors treated with rapamycin, exposing new avenues for designing more efficient treatments for TSC patients.

  6. CD9 may contribute to the survival of human germinal center B cells by facilitating the interaction with follicular dendritic cells

    Directory of Open Access Journals (Sweden)

    Sun-Ok Yoon

    2014-01-01

    Full Text Available The germinal center (GC is a dynamic microenvironment where antigen (Ag-activated B cells rapidly expand and differentiate, generating plasma cells (PC that produce high-affinity antibodies. Precise regulation of survival and proliferation of Ag-activated B cells within the GC is crucial for humoral immune responses. The follicular dendritic cells (FDC are the specialized stromal cells in the GC that prevent apoptosis of GC-B cells. Recently, we reported that human GC-B cells consist of CD9+ and CD9− populations and that it is the CD9+ cells that are committed to the PC lineage. In this study, we investigated the functional role of CD9 on GC-B cells. Tonsillar tissue section staining revealed that in vivo CD9+ GC-B cells localized in the light zone FDC area. Consistent this, in vitro CD9+ GC-B cells survived better than CD9− GC-B cells in the presence of HK cells, an FDC line, in a cell–cell contact-dependent manner. The frozen tonsillar tissue section binding assay showed that CD9+ GC-B cells bound to the GC area of tonsillar tissues significantly more than the CD9− GC-B cells did and that the binding was significantly inhibited by neutralizing anti-integrin β1 antibody. Furthermore, CD9+ cells bound to soluble VCAM-1 more than CD9− cells did, resulting in activation and stabilization of the active epitope of integrin β1. All together, our data suggest that CD9 on GC-B cells contributes to survival by strengthening their binding to FDC through the VLA4/VCAM-1 axis.

  7. Survival and death of epiblast cells during embryonic stem cell derivation revealed by long-term live-cell imaging with an Oct4 reporter system.

    Science.gov (United States)

    Yamagata, Kazuo; Ueda, Jun; Mizutani, Eiji; Saitou, Mitinori; Wakayama, Teruhiko

    2010-10-01

    Despite the broad literature on embryonic stem cells (ESCs), their derivation process remains enigmatic. This may be because of the lack of experimental systems that can monitor this prolonged cellular process. Here we applied a live-cell imaging technique to monitor the process of ESC derivation over 10 days from morula to outgrowth phase using an Oct4/eGFP reporter system. Our imaging reflects the 'natural' state of ESC derivation, as the ESCs established after the imaging were both competent in chimeric mice formation and germ-line transmission. Using this technique, ESC derivation in conventional conditions was imaged. After the blastocoel was formed, the intensity of Oct4 signals attenuated in the trophoblast cells but was maintained in the inner cell mass (ICM). Thereafter, the Oct4-positive cells scattered and their number decreased along with apoptosis of the other Oct4-nagative cells likely corresponds to trophoblast and hypoblast cells, and then only the surviving Oct4-positive cells proliferated and formed the colony. All embryos without exception passed through this cell death phase. Importantly, the addition of caspase inhibitor Z-VAD-FMK to the medium dramatically suppressed the loss of Oct4-positive cells and also other embryo-derived cells, suggesting that the cell deaths was induced by a caspase-dependent apoptotic pathway. Next we imaged the ESC derivation in 3i medium, which consists of chemical compounds that can suppress differentiation. The most significant difference between the conventional and 3i methods was that there was no obvious cell death in 3i, so that the colony formation was rapid and all of the Oct4-positive cells contributed to the formation of the outgrown colony. These data indicate that the prevention of cell death in epiblast cells is one of the important events for the successful establishment of ESCs. Thus, our imaging technique can advance the understanding of the time-dependent cellular changes during ESC derivation.

  8. Survival of akinetes (resting-state cells of cyanobacteria) in low earth orbit and simulated extraterrestrial conditions.

    Science.gov (United States)

    Olsson-Francis, Karen; de la Torre, Rosa; Towner, Martin C; Cockell, Charles S

    2009-12-01

    Cyanobacteria are photosynthetic organisms that have been considered for space applications, such as oxygen production in bioregenerative life support systems, and can be used as a model organism for understanding microbial survival in space. Akinetes are resting-state cells of cyanobacteria that are produced by certain genera of heterocystous cyanobacteria to survive extreme environmental conditions. Although they are similar in nature to endospores, there have been no investigations into the survival of akinetes in extraterrestrial environments. The aim of this work was to examine the survival of akinetes from Anabaena cylindrica in simulated extraterrestrial conditions and in Low Earth Orbit (LEO). Akinetes were dried onto limestone rocks and sent into LEO for 10 days on the ESA Biopan VI. In ground-based experiments, the rocks were exposed to periods of desiccation, vacuum (0.7×10(-3) kPa), temperature extremes (-80 to 80°C), Mars conditions (-27°C, 0.8 kPa, CO(2)) and UV radiation (325-400 nm). A proportion of the akinete population was able to survive a period of 10 days in LEO and 28 days in Mars simulated conditions, when the rocks were not subjected to UV radiation. Furthermore, the akinetes were able to survive 28 days of exposure to desiccation and low temperature with high viability remaining. Yet long periods of vacuum and high temperature were lethal to the akinetes. This work shows that akinetes are extreme-tolerating states of cyanobacteria that have a practical use in space applications and yield new insight into the survival of microbial resting-state cells in space conditions.

  9. Efficient long-term survival of cell grafts after myocardial infarction with thick viable cardiac tissue entirely from pluripotent stem cells.

    Science.gov (United States)

    Matsuo, Takehiko; Masumoto, Hidetoshi; Tajima, Shuhei; Ikuno, Takeshi; Katayama, Shiori; Minakata, Kenji; Ikeda, Tadashi; Yamamizu, Kohei; Tabata, Yasuhiko; Sakata, Ryuzo; Yamashita, Jun K

    2015-11-20

    Poor engraftment of cells after transplantation to the heart is a common and unresolved problem in the cardiac cell therapies. We previously generated cardiovascular cell sheets entirely from pluripotent stem cells with cardiomyocytes, endothelial cells and vascular mural cells. Though sheet transplantation showed a better engraftment and improved cardiac function after myocardial infarction, stacking limitation (up to 3 sheets) by hypoxia hampered larger structure formation and long-term survival of the grafts. Here we report an efficient method to overcome the stacking limitation. Insertion of gelatin hydrogel microspheres (GHMs) between each cardiovascular cell sheet broke the viable limitation via appropriate spacing and fluid impregnation with GHMs. Fifteen sheets with GHMs (15-GHM construct; >1 mm thickness) were stacked within several hours and viable after 1 week in vitro. Transplantation of 5-GHM constructs (≈2 × 10(6) of total cells) to a rat myocardial infarction model showed rapid and sustained functional improvements. The grafts were efficiently engrafted as multiple layered cardiovascular cells accompanied by functional capillary networks. Large engrafted cardiac tissues (0.8 mm thickness with 40 cell layers) successfully survived 3 months after TX. We developed an efficient method to generate thicker viable tissue structures and achieve long-term survival of the cell graft to the heart.

  10. Biomineralization of Uranium by PhoY Phosphatase Activity Aids Cell Survival in Caulobacter crescentus

    Energy Technology Data Exchange (ETDEWEB)

    Yung, M C [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jiao, Y [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-07-22

    Caulobacter crescentus is known to tolerate high levels of uranium [U(VI)], but its detoxification mechanism is poorly understood. Here we show that C. crescentus is able to facilitate U(VI) biomineralization through the formation of U-Pi precipitates via its native alkaline phosphatase activity. The U-Pi precipitates, deposited on the cell surface in the form of meta-autunite structures, have a lower U/Pi ratio than do chemically produced precipitates. The enzyme that is responsible for the phosphatase activity and thus the biomineralization process is identified as PhoY, a periplasmic alkaline phosphatase with broad substrate specificity. Furthermore, PhoY is shown to confer a survival advantage on C. crescentus toward U(VI) under both growth and nongrowth conditions. Results obtained in this study thus highlight U(VI) biomineralization as a resistance mechanism in microbes, which not only improves our understanding of bacterium-mineral interactions but also aids in defining potential ecological niches for metal-resistant bacteria.

  11. EMMPRIN expression in oral squamous cell carcinomas: correlation with tumor proliferation and patient survival.

    Science.gov (United States)

    Monteiro, Luís Silva; Delgado, Maria Leonor; Ricardo, Sara; Garcez, Fernanda; do Amaral, Barbas; Pacheco, José Júlio; Lopes, Carlos; Bousbaa, Hassan

    2014-01-01

    The aim of our study was to explore the clinicopathological and prognostic significance of extracellular matrix metalloproteinase inducer (EMMPRIN) expression in oral squamous cell carcinomas (OSCC), and its relation with the proliferative tumor status of OSCC. We examined EMMPRIN and Ki-67 proteins expression by immunohistochemistry in 74 cases with OSCC. Statistical analysis was conducted to examine their clinicopathological and prognostic significance in OSCC. EMMPRIN membrane expression was observed in all cases, with both membrane and cytoplasmic tumor expression in 61 cases (82.4%). EMMPRIN overexpression was observed in 56 cases (75.7%). Moderately or poorly differentiated tumors showed EMMPRIN overexpression more frequently than well-differentiated tumors (P = 0.002). Overexpression of EMMPRIN was correlated with high Ki-67 expression (P = 0.004). In the multivariate analysis, EMMPRIN overexpression reveals an adverse independent prognostic value for cancer-specific survival (CSS) (P = 0.034). Our results reveal that EMMPRIN protein is overexpressed in more than two-thirds of OSCC cases, especially in high proliferative and less differentiated tumors. The independent value of EMMPRIN overexpression in CSS suggests that this protein could be used as an important biological prognostic marker for patients with OSCC. Moreover, the high expression of EMMPRIN makes it a possible therapeutic target in OSCC patients.

  12. Biomineralization of uranium by PhoY phosphatase activity aids cell survival in Caulobacter crescentus.

    Science.gov (United States)

    Yung, Mimi C; Jiao, Yongqin

    2014-08-01

    Caulobacter crescentus is known to tolerate high levels of uranium [U(VI)], but its detoxification mechanism is poorly understood. Here we show that C. crescentus is able to facilitate U(VI) biomineralization through the formation of U-Pi precipitates via its native alkaline phosphatase activity. The U-Pi precipitates, deposited on the cell surface in the form of meta-autunite structures, have a lower U/Pi ratio than do chemically produced precipitates. The enzyme that is responsible for the phosphatase activity and thus the biomineralization process is identified as PhoY, a periplasmic alkaline phosphatase with broad substrate specificity. Furthermore, PhoY is shown to confer a survival advantage on C. crescentus toward U(VI) under both growth and nongrowth conditions. Results obtained in this study thus highlight U(VI) biomineralization as a resistance mechanism in microbes, which not only improves our understanding of bacterium-mineral interactions but also aids in defining potential ecological niches for metal-resistant bacteria.

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Novel gene ashwin functions in Xenopus cell survival and anteroposterior patterning.

    Science.gov (United States)

    Patil, Sonali S; Alexander, Tara B; Uzman, J Akif; Lou, Chih-Hong; Gohil, Himika; Sater, Amy K

    2006-07-01

    The novel gene ashwin was isolated in a differential display screen for genes activated or up-regulated early in neural specification. ashwin is expressed maternally and zygotically, and it is up-regulated in the neural ectoderm after the midgastrula stage. It is expressed in the neural plate and later in the embryonic brain, eyes, and spinal cord. Overexpression of ashwin in whole embryos leads to anterior truncations and other defects. However, a second Organizer does not form, and the secondary axial structures may result from splitting of the Organizer, rather than axis duplication. Morpholino oligonucleotide-mediated reduction in ashwin expression leads to lethality or abnormalities in gastrulation, as well as significant apoptosis in midgastrula embryos. Apoptosis is also observed in midgastrula embryos overexpressing ashwin. Coexpression of ashwin with the bone morphogenetic protein-4 antagonist noggin has a synergistic effect on neural-specific gene expression in isolated animal cap ectoderm. Ashwin has no previously characterized domains, although two nuclear localization signals can be identified. Orthologues have been identified in the human, mouse, chicken, and pufferfish genomes. Our results suggest that ashwin regulates cell survival and anteroposterior patterning.

  15. Prolongation of liver allograft survival by dendritic cells modified with NF-κB decoy oligodeoxynucleotides

    Institute of Scientific and Technical Information of China (English)

    Ming-Qing Xu; Yu-Ping Suo; Jian-Ping Gong; Ming-Man Zhang; Lü-Nan Yan

    2004-01-01

    significant allocostimulatory activity. NF-κB decoy ODNs completely abrogated IL-4-induced DC maturation and allocostimulatory activity as well as LPS-induced NF-κB activation and IL-12protein expression in DCs. GM-CSF+NF-κB decoy ODNspropagated DCs promoted apoptosis of liver allograftinfiltrating cells within portal areas, and significantly decreased the expression of IL-2 and IFN-γ mRNA but markedly elevated IL-4 mRNA expression both in liver allograft and in recipient spleen, and consequently suppressed liver allograft rejection, and promoted liver allograft survival.CONCLUSION: NF-κB decoy ODNs-modified DCs can prolong liver allograft survival by promoting apoptosis of graft-infiltrating cells within portal areas as well as downregulating IL-2 and IFN-γ mRNA and up-regulating IL-4 mRNA expression both in liver graft and in recipient spleen.

  16. Edg8/S1P5: an oligodendroglial receptor with dual function on process retraction and cell survival.

    Science.gov (United States)

    Jaillard, C; Harrison, S; Stankoff, B; Aigrot, M S; Calver, A R; Duddy, G; Walsh, F S; Pangalos, M N; Arimura, N; Kaibuchi, K; Zalc, B; Lubetzki, C

    2005-02-09

    Endothelial differentiation gene (Edg) proteins are G-protein-coupled receptors activated by lysophospholipid mediators: sphingosine-1-phosphate (S1P) or lysophosphatidic acid. We show that in the CNS, expression of Edg8/S1P5, a high-affinity S1P receptor, is restricted to oligodendrocytes and expressed throughout development from the immature stages to the mature myelin-forming cell. S1P activation of Edg8/S1P5 on O4-positive pre-oligodendrocytes induced process retraction via a Rho kinase/collapsin response-mediated protein signaling pathway, whereas no retraction was elicited by S1P on these cells derived from Edg8/S1P5-deficient mice. Edg8/S1P5-mediated process retraction was restricted to immature cells and was no longer observed at later developmental stages. In contrast, S1P activation promoted the survival of mature oligodendrocytes but not of pre-oligodendrocytes. The S1P-induced survival of mature oligodendrocytes was mediated through a pertussis toxin-sensitive, Akt-dependent pathway. Our data demonstrate that Edg8/S1P5 activation on oligodendroglial cells modulates two distinct functional pathways mediating either process retraction or cell survival and that these effects depend on the developmental stage of the cell.

  17. HTLV-1 tax stabilizes MCL-1 via TRAF6-dependent K63-linked polyubiquitination to promote cell survival and transformation.

    Science.gov (United States)

    Choi, Young Bong; Harhaj, Edward William

    2014-10-01

    The human T-cell leukemia virus type 1 (HTLV-1) Tax protein hijacks the host ubiquitin machinery to activate IκB kinases (IKKs) and NF-κB and promote cell survival; however, the key ubiquitinated factors downstream of Tax involved in cell transformation are unknown. Using mass spectrometry, we undertook an unbiased proteome-wide quantitative survey of cellular proteins modified by ubiquitin in the presence of Tax or a Tax mutant impaired in IKK activation. Tax induced the ubiquitination of 22 cellular proteins, including the anti-apoptotic BCL-2 family member MCL-1, in an IKK-dependent manner. Tax was found to promote the nondegradative lysine 63 (K63)-linked polyubiquitination of MCL-1 that was dependent on the E3 ubiquitin ligase TRAF6 and the IKK complex. Tax interacted with and activated TRAF6, and triggered its mitochondrial localization, where it conjugated four carboxyl-terminal lysine residues of MCL-1 with K63-linked polyubiquitin chains, which stabilized and protected MCL-1 from genotoxic stress-induced degradation. TRAF6 and MCL-1 played essential roles in the survival of HTLV-1 transformed cells and the immortalization of primary T cells by HTLV-1. Therefore, K63-linked polyubiquitination represents a novel regulatory mechanism controlling MCL-1 stability that has been usurped by a viral oncogene to precipitate cell survival and transformation.

  18. Cell cycle and aging, morphogenesis, and response to stimuli genes are individualized biomarkers of glioblastoma progression and survival

    Directory of Open Access Journals (Sweden)

    Southey Bruce R

    2011-06-01

    . Biological processes associated glioblastoma survival included morphogenesis, cell cycle, aging, response to stimuli, and programmed cell death. Conclusions Known biomarkers of glioblastoma survival were confirmed, and new general and clinical-dependent gene profiles were uncovered. The comparison of biomarkers across glioblastoma phases and functional analyses offered insights into the role of genes. These findings support the development of more accurate and personalized prognostic tools and gene-based therapies that improve the survival and quality of life of individuals afflicted by glioblastoma multiforme.

  19. Pretreatment metabolic tumour volume is predictive of disease-free survival and overall survival in patients with oesophageal squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Lemarignier, Charles; Gouel, Pierrick [Centre Henri Becquerel and Rouen University Hospital, Department of Nuclear Medicine, Rouen (France); Di Fiore, Frederic [Rouen University Hospital, Department of Gastroenterology, Rouen (France); Centre Henri Becquerel, Department of Medical oncology, Rouen (France); Marre, Charline; Michel, Pierre [Rouen University Hospital, Department of Gastroenterology, Rouen (France); Hapdey, Sebastien; Modzelewski, Romain; Vera, Pierre [Centre Henri Becquerel and Rouen University Hospital, Department of Nuclear Medicine, Rouen (France); University of Rouen, QuantIF (Litis EA 4108 - FR CNRS 3638), Rouen (France); Dubray, Bernard [University of Rouen, QuantIF (Litis EA 4108 - FR CNRS 3638), Rouen (France); Centre Henri Becquerel and Rouen University Hospital, Department of Radiotherapy and Medical Physics, Rouen (France)

    2014-11-15

    It has been suggested that FDG PET has predictive value for the prognosis of treated oesophageal carcinoma. However, the studies reported in the literature have shown discordant results. The aim of this study was to determine whether pretherapy quantitative metabolic parameters correlate with patient outcomes. Included in the study were 67 patients with a histological diagnosis of oesophageal squamous cell carcinoma. Each patient underwent {sup 18}F-FDG PET (4.5 MBq/kg) before chemoradiotherapy. Quantitative analysis was performed using the following parameters: age, weight loss, location, N stage, OMS performance status, MTV{sub p} and MTV{sub p'} (metabolic tumour volume determined by two different physicians), MTV{sub 40%} (volume for a threshold of 40 % of SUVmax), MTV{sub a} (volume automatically determined with a contrast-based adaptive threshold method), SUVmax, SUVmean and TLG (total lesion glycolysis). MTV{sub p} and MTV{sub 40%} were highly correlated (Pearson's index 0.92). SUVmean{sub p} and SUVmean{sub 40%} were also correlated (Pearson's index 0.86), as were TLG{sub p} and TLG{sub 40%} (Pearson's index 0.98). Similarly, the parameters obtained with the adaptive threshold method (MTV{sub a}, SUVmean{sub a} and TLG{sub a}) were correlated with those obtained manually (MTV{sub p}, SUVmean{sub p} and TLG{sub p}). The manual metabolic tumour volume determination (MTV{sub p} and MTV{sub p'}) was reproducible. Multivariate analysis for disease-free survival (DFS) showed that a larger MTV{sub p} was associated with a shorter DFS (p = 0.004) and that a higher SUVmax was associated with a longer DFS (p = 0.02). Multivariate analysis for overall survival (OS) showed that a larger MTV{sub p} was associated with a shorter OS (p = 0.01) and that a tumour in the distal oesophagus was associated with a longer OS (p = 0.005). The associations among the other parameters were not statistically significant. Metabolic tumour volume is a major

  20. Stress-induced nuclear RNA degradation pathways regulate yeast bromodomain factor 2 to promote cell survival.

    Directory of Open Access Journals (Sweden)

    Kevin Roy

    2014-09-01

    Full Text Available Bromodomain proteins are key regulators of gene expression. How the levels of these factors are regulated in specific environmental conditions is unknown. Previous work has established that expression of yeast Bromodomain factor 2 (BDF2 is limited by spliceosome-mediated decay (SMD. Here we show that BDF2 is subject to an additional layer of post-transcriptional control through RNase III-mediated decay (RMD. We found that the yeast RNase III Rnt1p cleaves a stem-loop structure within the BDF2 mRNA to down-regulate its expression. However, these two nuclear RNA degradation pathways play distinct roles in the regulation of BDF2 expression, as we show that the RMD and SMD pathways of the BDF2 mRNA are differentially activated or repressed in specific environmental conditions. RMD is hyper-activated by salt stress and repressed by hydroxyurea-induced DNA damage while SMD is inactivated by salt stress and predominates during DNA damage. Mutations of cis-acting signals that control SMD and RMD rescue numerous growth defects of cells lacking Bdf1p, and show that SMD plays an important role in the DNA damage response. These results demonstrate that specific environmental conditions modulate nuclear RNA degradation pathways to control BDF2 expression and Bdf2p-mediated gene regulation. Moreover, these results show that precise dosage of Bromodomain factors is essential for cell survival in specific environmental conditions, emphasizing their importance for controlling chromatin structure and gene expression in response to environmental stress.

  1. B-cell receptor-associated protein 31 regulates human embryonic stem cell adhesion, stemness, and survival via control of epithelial cell adhesion molecule.

    Science.gov (United States)

    Kim, Won-Tae; Seo Choi, Hong; Min Lee, Hyun; Jang, Young-Joo; Ryu, Chun Jeih

    2014-10-01

    B-Cell receptor-associated protein 31 (BAP31) regulates the export of secreted membrane proteins from the endoplasmic reticulum (ER) to the downstream secretory pathway. Previously, we generated a monoclonal antibody 297-D4 against the surface molecule on undifferentiated human embryonic stem cells (hESCs). Here, we found that 297-D4 antigen was localized to pluripotent hESCs and downregulated during early differentiation of hESCs and identified that the antigen target of 297-D4 was BAP31 on the hESC-surface. To investigate the functional role of BAP31 in hESCs, BAP31 expression was knocked down by small interfering RNA. BAP31 depletion impaired hESC self-renewal and pluripotency and drove hESC differentiation into multicell lineages. BAP31 depletion hindered hESC proliferation by arresting cell cycle at G0/G1 phase and inducing caspase-independent cell death. Interestingly, BAP31 depletion reduced hESC adhesion to extracellular matrix (ECM). Analysis of cell surface molecules showed decreased expression of epithelial cell adhesion molecule (EpCAM) in BAP31-depleted hESCs, while ectopic expression of BAP31 elevated the expression of EpCAM. EpCAM depletion also reduced hESC adhesion to ECM, arrested cell cycle at G0/G1 phase and induced cell death, producing similar effects to those of BAP31 depletion. BAP31 and EpCAM were physically associated and colocalized at the ER and cell surface. Both BAP31 and EpCAM depletion decreased cyclin D1 and E expression and suppressed PI3K/Akt signaling, suggesting that BAP31 regulates hESC stemness and survival via control of EpCAM expression. These findings provide, for the first time, mechanistic insights into how BAP31 regulates hESC stemness and survival via control of EpCAM expression.

  2. Surviving mossy cells enlarge and receive more excitatory synaptic input in a mouse model of temporal lobe epilepsy.

    Science.gov (United States)

    Zhang, Wei; Thamattoor, Ajoy K; LeRoy, Christopher; Buckmaster, Paul S

    2015-05-01

    Numerous hypotheses of temporal lobe epileptogenesis have been proposed, and several involve hippocampal mossy cells. Building on previous hypotheses we sought to test the possibility that after epileptogenic injuries surviving mossy cells develop into super-connected seizure-generating hub cells. If so, they might require more cellular machinery and consequently have larger somata, elongate their dendrites to receive more synaptic input, and display higher frequencies of miniature excitatory synaptic currents (mEPSCs). To test these possibilities pilocarpine-treated mice were evaluated using GluR2-immunocytochemistry, whole-cell recording, and biocytin-labeling. Epileptic pilocarpine-treated mice displayed substantial loss of GluR2-positive hilar neurons. Somata of surviving neurons were 1.4-times larger than in controls. Biocytin-labeled mossy cells also were larger in epileptic mice, but dendritic length per cell was not significantly different. The average frequency of mEPSCs of mossy cells recorded in the presence of tetrodotoxin and bicuculline was 3.2-times higher in epileptic pilocarpine-treated mice as compared to controls. Other parameters of mEPSCs were similar in both groups. Average input resistance of mossy cells in epileptic mice was reduced to 63% of controls, which is consistent with larger somata and would tend to make surviving mossy cells less excitable. Other intrinsic physiological characteristics examined were similar in both groups. Increased excitatory synaptic input is consistent with the hypothesis that surviving mossy cells develop into aberrantly super-connected seizure-generating hub cells, and soma hypertrophy is indirectly consistent with the possibility of axon sprouting. However, no obvious evidence of hyperexcitable intrinsic physiology was found. Furthermore, similar hypertrophy and hyper-connectivity has been reported for other neuron types in the dentate gyrus, suggesting mossy cells are not unique in this regard. Thus

  3. Modeling Stochastic Variability in the Numbers of Surviving Salmonella enterica, Enterohemorrhagic Escherichia coli, and Listeria monocytogenes Cells at the Single-Cell Level in a Desiccated Environment.

    Science.gov (United States)

    Koyama, Kento; Hokunan, Hidekazu; Hasegawa, Mayumi; Kawamura, Shuso; Koseki, Shigenobu

    2017-02-15

    Despite effective inactivation procedures, small numbers of bacterial cells may still remain in food samples. The risk that bacteria will survive these procedures has not been estimated precisely because deterministic models cannot be used to describe the uncertain behavior of bacterial populations. We used t