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Sample records for cell survival roles

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

    International Nuclear Information System (INIS)

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

  2. Role of DNA deletion length in mutation and cell survival

    International Nuclear Information System (INIS)

    A model is presented which is based on the assumption that malignant transformation, mutation, chromosome aberration, and reproductive death of cells are all manifestations of radiation induced deletions in the DNA of the cell, and that the size of the deletion in relation to the spacing of essential genes determines the consequences of that deletion. It is assumed that two independent types of potentially lethal lesions can result in DNA deletions, and that the relative numbers of these types of damage is dependent on radiation quality. The repair of the damage reduces the length of a deletion, but does not always eliminate it. The predictions of this model are in good agreement with a wide variety of experimental evidence. (author)

  3. Possible role of pineal allopregnanolone in Purkinje cell survival

    OpenAIRE

    Haraguchi, Shogo; Hara, Sakurako; Ubuka, Takayoshi; Mita, Masatoshi; Tsutsui, Kazuyoshi

    2012-01-01

    It is believed that neurosteroids are produced in the brain and other nervous systems. Here, we show that allopregnanolone (ALLO), a neurosteroid, is exceedingly produced in the pineal gland compared with the brain and that pineal ALLO acts on the Purkinje cell, a principal cerebellar neuron, to prevent apoptosis in the juvenile quail. We first demonstrated that the pineal gland is a major organ of neurosteroidogenesis. A series of experiments using molecular and biochemical techniques has fu...

  4. Pax8 has a critical role in epithelial cell survival and proliferation

    OpenAIRE

    Di Palma, T; Filippone, M G; Pierantoni, G. M.; Fusco, A; S. Soddu; Zannini, M

    2013-01-01

    The transcription factor Pax8, a member of the Paired-box gene family, is a critical regulator required for proper development and differentiation of thyroid follicular cells. Despite being Pax8 well characterized with respect to its role in regulating genes responsible for thyroid differentiation, its involvement in cell survival and proliferation has been hypothesized but remains unclear. Here, we show that Pax8 overexpression significantly increases proliferation and colony-forming efficie...

  5. Bim and Mcl-1 exert key roles in regulating JAK2V617F cell survival

    Directory of Open Access Journals (Sweden)

    Guthy Daniel A

    2011-01-01

    Full Text Available Abstract Background The JAK2V617F mutation plays a major role in the pathogenesis of myeloproliferative neoplasms and is found in the vast majority of patients suffering from polycythemia vera and in roughly every second patient suffering from essential thrombocythemia or from primary myelofibrosis. The V617F mutation is thought to provide hematopoietic stem cells and myeloid progenitors with a survival and proliferation advantage. It has previously been shown that activated JAK2 promotes cell survival by upregulating the anti-apoptotic STAT5 target gene Bcl-xL. In this study, we have investigated the role of additional apoptotic players, the pro-apoptotic protein Bim as well as the anti-apoptotic protein Mcl-1. Methods Pharmacological inhibition of JAK2/STAT5 signaling in JAK2V617F mutant SET-2 and MB-02 cells was used to study effects on signaling, cell proliferation and apoptosis by Western blot analysis, WST-1 proliferation assays and flow cytometry. Cells were transfected with siRNA oligos to deplete candidate pro- and anti-apoptotic proteins. Co-immunoprecipitation assays were performed to assess the impact of JAK2 inhibition on complexes of pro- and anti-apoptotic proteins. Results Treatment of JAK2V617F mutant cell lines with a JAK2 inhibitor was found to trigger Bim activation. Furthermore, Bim depletion by RNAi suppressed JAK2 inhibitor-induced cell death. Bim activation following JAK2 inhibition led to enhanced sequestration of Mcl-1, besides Bcl-xL. Importantly, Mcl-1 depletion by RNAi was sufficient to compromise JAK2V617F mutant cell viability and sensitized the cells to JAK2 inhibition. Conclusions We conclude that Bim and Mcl-1 have key opposing roles in regulating JAK2V617F cell survival and propose that inactivation of aberrant JAK2 signaling leads to changes in Bim complexes that trigger cell death. Thus, further preclinical evaluation of combinations of JAK2 inhibitors with Bcl-2 family antagonists that also tackle Mcl-1

  6. Bim and Mcl-1 exert key roles in regulating JAK2V617F cell survival

    International Nuclear Information System (INIS)

    The JAK2V617F mutation plays a major role in the pathogenesis of myeloproliferative neoplasms and is found in the vast majority of patients suffering from polycythemia vera and in roughly every second patient suffering from essential thrombocythemia or from primary myelofibrosis. The V617F mutation is thought to provide hematopoietic stem cells and myeloid progenitors with a survival and proliferation advantage. It has previously been shown that activated JAK2 promotes cell survival by upregulating the anti-apoptotic STAT5 target gene Bcl-xL. In this study, we have investigated the role of additional apoptotic players, the pro-apoptotic protein Bim as well as the anti-apoptotic protein Mcl-1. Pharmacological inhibition of JAK2/STAT5 signaling in JAK2V617F mutant SET-2 and MB-02 cells was used to study effects on signaling, cell proliferation and apoptosis by Western blot analysis, WST-1 proliferation assays and flow cytometry. Cells were transfected with siRNA oligos to deplete candidate pro- and anti-apoptotic proteins. Co-immunoprecipitation assays were performed to assess the impact of JAK2 inhibition on complexes of pro- and anti-apoptotic proteins. Treatment of JAK2V617F mutant cell lines with a JAK2 inhibitor was found to trigger Bim activation. Furthermore, Bim depletion by RNAi suppressed JAK2 inhibitor-induced cell death. Bim activation following JAK2 inhibition led to enhanced sequestration of Mcl-1, besides Bcl-xL. Importantly, Mcl-1 depletion by RNAi was sufficient to compromise JAK2V617F mutant cell viability and sensitized the cells to JAK2 inhibition. We conclude that Bim and Mcl-1 have key opposing roles in regulating JAK2V617F cell survival and propose that inactivation of aberrant JAK2 signaling leads to changes in Bim complexes that trigger cell death. Thus, further preclinical evaluation of combinations of JAK2 inhibitors with Bcl-2 family antagonists that also tackle Mcl-1, besides Bcl-xL, is warranted to assess the therapeutic potential for

  7. The role of autophagy in cell survival from heavy ion irradiation in the plateau region

    International Nuclear Information System (INIS)

    To study cytotoxic effect of heavy ion irradiation in the plateau region, and investigate whether autophagy induced by heavy ion irradiation is cytoprotective, HeLa cells were irradiated with 350 MeV/u carbon ions beams, and the clonogenic survival was analyzed. The results showed that cell survival decreased with increasing doses. It was also found that G2/M-phase cells increased, and the autophagy-related activity was significantly higher than the control. When autophagy was blocked by 3-methyladenine in carbon-ion irradiated cells, G2/M phase arrest and the percentage of apoptosis cells were further elevated, and cell survival decreased significantly, indicating the induction of cytoprotective autophagy by carbon-ion irradiation. Our results demonstrated that autophagy induced by carbon ion irradiation provided a self-protective mechanism in HeLa cells, short-time inhibition of autophagy before carbon-ion irradiation could enhance radiation cytotoxicity in HeLa cells. (authors)

  8. Predictive role of vascular endothelial growth factor polymorphisms in the survival of renal cell carcinoma patients.

    Science.gov (United States)

    Yang, Y-Q; Chen, J

    2014-01-01

    We conducted a study to investigate the possible role of the vascular endothelial growth factor (VEGF) polymorphisms -2578C/A, -1154G/A and -634C/G and clinical factors in renal cell carcinoma (RCC) prognosis in a cohort of 336 RCC cases. A total of 336 patients with RCC were recruited from PLA General Hospital between January 2004 and December 2005. All patients were followed up until December 2010, and no patient was lost to follow-up. The follow-up time of this study was 60 months. At the time of analysis, a total of 210 died during the follow-up. The median overall survival for patients was 29.1 months (95%CI = 17.1 to 41.3 months), and the 5-year survival rate for the patients was 37.5%. Our study showed that Karnofsky performance status ≥60 could delay death from RCC, with HR (95%CI) of 0.57 (0.39-0.84). Patients with anemia, platelet count >400 x 10(9)/L, neutrophilia and lymphocytes >160 g/L had increased risk of death from RCC, with HR (95%CI) of 1.84 (1.18-2.96), 2.01 (1.27-3.25), 1.65 (1.03-2.56) and 1.49 (0.99-2.71), respectively. The VEGF -2578AA and -1154AA genotypes were significantly associated with a poor overall survival of RCC patients, with HR (95%CI) of 2.41 (1.32-5.13) and 3.77 (1.42-15.67), respectively. In conclusion, our study presented the factors regarding the prognosis of RCC patients, and high platelet and neutrophil counts, low lymphocytes, and VEGF -2578C/A and -1154G/A polymorphisms were shown to be independent factors for a lower prognosis of RCC patients. PMID:25062489

  9. 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. PMID:27022440

  10. 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.

  11. A physiologic three-dimensional cell culture system to investigate the role of decorin in matrix organisation and cell survival

    International Nuclear Information System (INIS)

    In vivo cells exist in a three-dimensional environment generated and maintained by multiple cell-cell and cell-matrix interactions. Proteoglycans, like decorin, affect these complex interactions. Thus, we sought to investigate the role of decorin in a three-dimensional environment where the matrix was generated over time by decorin-deficient fibroblasts in the presence of L-ascorbic acid 2-phosphate. The cells were viable and proliferated in response to FGF2. Decorin was incorporated in the matrix and caused a ∼2 nm shift in the average diameter of the collagen fibrils, and the range and distribution of the fibrils became narrower and more uniform. Although there were no appreciable changes in collagen composition, we found that exogenous decorin induced the de novo synthesis of collagen I and V and cross-linked β (I). In the early phases of the three-dimensional culture, decorin reduced apoptosis. However, following the establishment of a three-dimensional matrix, the cells did not require decorin for their survival

  12. Role of CDK5/cyclin complexes in ischemia-induced death and survival of renal tubular cells

    Science.gov (United States)

    Guevara, Tatiana; Sancho, Mónica; Pérez-Payá, Enrique; Orzáez, Mar

    2014-01-01

    Ischemia reperfusion processes induce damage in renal tubules and compromise the viability of kidney transplants. Understanding the molecular events responsible for tubule damage and recovery would help to develop new strategies for organ preservation. CDK5 has been traditionally considered a neuronal kinase with dual roles in cell death and survival. Here, we demonstrate that CDK5 and their regulators p35/p25 and cyclin I are also expressed in renal tubular cells. We show that treatment with CDK inhibitors promotes the formation of pro-survival CDK5/cyclin I complexes and enhances cell survival upon an ischemia reperfusion pro-apoptotic insult. These findings support the benefit of treating with CDK inhibitors for renal preservation, assisting renal tubule protection. PMID:24675881

  13. A key role for ATF3 in regulating mast cell survival and mediator release

    OpenAIRE

    Gilchrist, Mark; Henderson, William R.; Morotti, Andrew; Carrie D. Johnson; Nachman, Alex; Schmitz, Frank; Smith, Kelly D.; Aderem, Alan

    2010-01-01

    Activating transcription factor 3 (ATF3) is a basic leucine zipper transcription factor that plays a regulatory role in inflammation, cell division, and apoptosis. Mast cells (MCs) initiate many inflammatory responses and have a central role in allergy and allergic diseases. We report here that ATF3 has a central role in MC development and function. Bone marrow–derived MC populations from ATF3-deficient mice are unresponsive to interleukin-3 (IL-3)–induced maturation signals, and this correla...

  14. Conditional knockdown of BCL2A1 reveals rate-limiting roles in BCR-dependent B-cell survival.

    Science.gov (United States)

    Sochalska, M; Ottina, E; Tuzlak, S; Herzog, S; Herold, M; Villunger, A

    2016-04-01

    Bcl2 family proteins control mitochondrial apoptosis and its members exert critical cell type and differentiation stage-specific functions, acting as barriers against autoimmunity or transformation. Anti-apoptotic Bcl2a1/Bfl1/A1 is frequently deregulated in different types of blood cancers in humans but its physiological role is poorly understood as quadruplication of the Bcl2a1 gene locus in mice hampers conventional gene targeting strategies. Transgenic overexpression of A1, deletion of the A1-a paralogue or constitutive knockdown in the hematopoietic compartment of mice by RNAi suggested rate-limiting roles in lymphocyte development, granulopoiesis and mast cell activation. Here we report on the consequences of conditional knockdown of A1 protein expression using a reverse transactivator (rtTA)-driven approach that highlights a critical role for this Bcl2 family member in the maintenance of mature B-cell homeostasis. Furthermore, we define the A1/Bim (Bcl-2 interacting mediator of cell death) axis as a target of key kinases mediating B-cell receptor (BCR)-dependent survival signals, such as, spleen tyrosine kinase (Syk) and Brutons tyrosine kinase (Btk). As such, A1 represents a putative target for the treatment of B-cell-related pathologies depending on hyperactivation of BCR-emanating survival signals and loss of A1 expression accounts, in part, for the pro-apoptotic effects of Syk- or Btk inhibitors that rely on the 'BH3-only' protein Bim for cell killing. PMID:26450454

  15. Role of ATG10 expression quantitative trait loci in non-small cell lung cancer survival.

    Science.gov (United States)

    Xie, Kaipeng; Liang, Cheng; Li, Qin; Yan, Caiwang; Wang, Cheng; Gu, Yayun; Zhu, Meng; Du, Fangzhi; Wang, Hui; Dai, Juncheng; Liu, Xiao'an; Jin, Guangfu; Shen, Hongbing; Ma, Hongxia; Hu, Zhibin

    2016-10-01

    The aim of this article was to evaluate whether genetic variants in autophagy-related genes affect the overall survival (OS) of non-small cell lung cancer (NSCLC) patients. We analyzed 14 single nucleotide polymorphisms (SNPs) in core autophagy-related genes for OS in 1,001 NSCLC patients. Three promising SNPs in ATG10 were subsequently annotated by the expression quantitative trait loci (eQTL) and methylation quantitative trait loci (meQTL) analyses based on Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) datasets. We observed that the variants of rs10514231, rs1864182 and rs1864183 were associated with poor lung cancer survival (HR = 1.33, 95% CI = 1.07-1.65; HR = 1.43, 95% CI = 1.13-1.81; HR = 1.38, 95% CI = 1.14-1.68, respectively) and positively correlated with ATG10 expression (all p lung cancer patients in TCGA dataset (HR = 2.10, 95% CI = 1.33-3.29). Moreover, the variants of rs10514231 and rs1864182 were associated with the increased methylation levels of cg17942617 (meQTL), which in turn contributed to the elevated ATG10 expression and decreased survival time. Further functional assays revealed that ATG10 facilitated lung cancer cell proliferation and migration. Our findings suggest that eQTL/meQTL variations of ATG10 could influence lung cancer survival through regulating ATG10 expression. PMID:27225307

  16. 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.

  17. Critical role for sphingosine kinase-1 in regulating survival of neuroblastoma cells exposed to amyloid-beta peptide.

    Science.gov (United States)

    Gomez-Brouchet, Anne; Pchejetski, Dimitri; Brizuela, Leyre; Garcia, Virginie; Altié, Marie-Françoise; Maddelein, Marie-Lise; Delisle, Marie-Bernadette; Cuvillier, Olivier

    2007-08-01

    We examined the role of sphingosine kinase-1 (SphK1), a critical regulator of the ceramide/sphingosine 1-phosphate (S1P) biostat, in the regulation of death and survival of SH-SY5Y neuroblastoma cells in response to amyloid beta (Abeta) peptide (25-35). Upon incubation with Abeta, SH-SY5Y cells displayed a marked down-regulation of SphK1 activity coupled with an increase in the ceramide/S1P ratio followed by cell death. This mechanism was redox-sensitive; N-acetylcysteine totally abrogated the down-regulation of SphK1 activity and strongly inhibited Abeta-induced cell death. SphK1 overexpression impaired the cytotoxicity of Abeta, whereas SphK1 silencing by RNA interference mimicked Abeta-induced cell death, thereby establishing a critical role for SphK1. We further demonstrated that SphK1 could mediate the well established cytoprotective action of insulin-like growth factor (IGF-I) against Abeta toxicity. A dominant-negative form of SphK1 or its pharmacological inhibition not only abrogated IGF-I-triggered stimulation of SphK1 but also hampered IGF-I protective effect. Similarly to IGF-I, the neuroprotective action of TGF-beta1 was also dependent on SphK1 activity; activation of SphK1 as well as cell survival were impeded by a dominant-negative form of SphK1. Taken together, these results provide the first illustration of SphK1 role as a critical regulator of death and survival of Abeta-treated cells. PMID:17522181

  18. Id4 knockdown during zebrafish development revealed its functional role in neural stem cell survival

    OpenAIRE

    Patlola, Santosh

    2010-01-01

    Id4 (Inhibitor of DNA binding 4 / Inhibitor of Differentiation 4) is one of the four members of Id protein family that antagonise the function of basic helix-loop-helix (bHLH) transcriptional regulators. In the mouse it has been shown that Id4 plays an important role in the timing of neural stem and progenitor cell differentiation and knockout mice exhibited premature neural stem cell differentiation resulting in significantly smaller brains. To further establish the molecular mechanism under...

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

    International Nuclear Information System (INIS)

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

  20. Critical role of Spns2, a sphingosine-1-phosphate transporter, in lung cancer cell survival and migration.

    Directory of Open Access Journals (Sweden)

    Eric Bradley

    Full Text Available The sphingosine-1-phosphate (S1P transporter Spns2 regulates myocardial precursor migration in zebrafish and lymphocyte trafficking in mice. However, its function in cancer has not been investigated. We show here that ectopic Spns2 expression induced apoptosis and its knockdown enhanced cell migration in non-small cell lung cancer (NSCLC cells. Metabolically, Spns2 expression increased the extracellular S1P level while its knockdown the intracellular. Pharmacological inhibition of S1P synthesis abolished the augmented cell migration mediated by Spns2 knockdown, indicating that intracellular S1P plays a key role in this process. Cell signaling studies indicated that Spns2 expression impaired GSK-3β and Stat3 mediated pro-survival pathways. Conversely, these pathways were activated by Spns2 knockdown, which explains the increased cell migration since they are also crucial for migration. Alterations of Spns2 were found to affect several enzymes involved in S1P metabolism, including sphingosine kinases, S1P phosphatases, and S1P lyase 1. Genetically, Spns2 mRNA level was found to be reduced in advanced lung cancer (LC patients as quantified by using a small scale qPCR array. These data show for the first time that Spns2 plays key roles in regulating the cellular functions in NSCLC cells, and that its down-regulation is a potential risk factor for LC.

  1. Role of gender in the survival of surgical patients with nonsmall cell lung cancer

    Directory of Open Access Journals (Sweden)

    Nóris C Scaglia

    2013-01-01

    Conclusions: Our results show female gender as a possible protective factor for better survival of stage I NSCLC patients, but not among stage II patients. This study adds data to the knowledge that combined both genders survival rates for NSCLC is not an adequate prognosis.

  2. Significant role of μ-calpain (CANP1) in proliferation/survival of bovine skeletal muscle satellite cells.

    Science.gov (United States)

    Van Ba, Hoa; Inho, Hwang

    2013-12-01

    Calpains are a family of Ca(2+)-dependent intracellular cysteine proteases, including the ubiquitously expressed μ-calpain (CANP1) and m-calpain (CANP2). The CANP1 has been found to play a central role in postmortem proteolysis and meat tenderization. However, the physiological roles of CANP1 in cattle skeletal satellite cells remain unclear. In this study, three small interference RNA sequences (siRNAs) targeting CANP1 gene were designed and ligated into pSilencer plasmid vector to construct shRNA expression constructs. Suppression of CANP1 in satellite cells was evaluated using these shRNA expressing constructs. Our results revealed that all three siRNAs could downregulate the expression of CANP1. Suppression of CANP1 significantly reduced cell viability in cell proliferation when compared with control cells. We found a crosstalk between CANP1 and caspase systems, particularly suppression of CANP1 resulted in an increase in the expressions of apoptotic caspases such as caspase-3, caspase-6, caspase-7, caspase-8, and caspase-9, as well as heat-shock protein (HSP) systems. Additionally, suppression of CANP1 led to the upregulation of other apoptosis and DNA damage-regulating genes whilst at the same time downregulating proliferation, migration, and differentiation-regulating genes. The results of our findings report for the first time that suppression of CANP1 resulted in the activation of caspase and HSP systems which might in turn regulate apoptosis through the caspase-dependent cell death pathway. This clearly demonstrates the key roles of CANP1 in regulation of cell proliferation and survival. PMID:23943438

  3. Characterization of intratumoral follicular helper T cells in follicular lymphoma: role in the survival of malignant B cells

    Science.gov (United States)

    Amé-Thomas, Patricia; Le Priol, Jérôme; Yssel, Hans; Caron, Gersende; Pangault, Céline; Jean, Rachel; Martin, Nadine; Marafioti, Teresa; Gaulard, Philippe; Lamy, Thierry; Fest, Thierry; Semana, Gilbert; Tarte, Karin

    2012-01-01

    Accumulating evidences indicate that the cellular and molecular microenvironment of follicular lymphoma (FL) plays a key role in both lymphomagenesis and patient outcome. Malignant FL B cells are found admixed to specific stromal and immune cell subsets, in particular CD4pos T cells displaying phenotypic features of follicular helper T cells (TFH). The goal of our study was to functionally characterize intratumoral CD4pos T cells. We showed that CXCR5hiICOShiCD4pos T cells sorted from FL biopsies comprise at least two separate cell populations with distinct genetic and functional features: i) CD25pos follicular regulatory T cells (TFR), and ii) CD25neg TFH displaying a FL-B cell supportive activity without regulatory functions. Furthermore, despite their strong similarities with tonsil-derived TFH, purified FL-derived TFH displayed a specific gene expression profile including an overexpression of several genes potentially involved directly or indirectly in lymphomagenesis, in particular TNF, LTA, IL4, or CD40LG. Interestingly, we further demonstrated that these two last signals efficiently rescued malignant B cells from spontaneous and Rituximab-induced apoptosis. Altogether, our study demonstrates that tumor-infiltrating CD4pos T cells are more heterogeneous than previously presumed, and underlines for the first time the crucial role of TFH in the complex set of cellular interactions within FL microenvironment. PMID:22015774

  4. Dual roles of NF-κB in cell survival and implications of NF-κB inhibitors in neuroprotective therapy

    Institute of Scientific and Technical Information of China (English)

    Zheng-hong QIN; Lu-yang TAO; Xin CHEN

    2007-01-01

    NF-κB is a well-characterized transcription factor with multiple physiological and pathological functions. NF-κB plays important roles in the development and maturation of lymphoids, regulation of immune and inflammatory response, and cell death and survival. The influence of NF-κB on cell survival could be protec- tive or destructive, depending on types, developmental stages of cells, and patho- logical conditions. The complexity of NF-rd3 in cell death and survival derives from its multiple roles in regulating the expression of a broad array of genes involved in promoting cell death and survival. The activation of NF-κB has been found in many neurological disorders, but its actual roles in pathogenesis are still being debated. Many compounds with neuroprotective actions are strongly as- sociated with the inhibition of NF-r,B, leading to speculation that blocking the pathological activation of NF-κB could offer neuroprotective effects in certain neurodegenerative conditions. This paper reviews the recent developments in understanding the dual roles of NF-κB in cell death and survival and explores its possible usefulness in treating neurological diseases. This paper will summarize the genes regulated by NF-κB that are involved in cell death and survival to elucidate why NF-r,B promotes cell survival in some conditions while facilitating cell death in other conditions. This paper will also focus on the effects of various NF-κB inhibitors on neuroprotection in certain pathological conditions to specu- late if NF-κB is a potential target for neuroprotective therapy.

  5. Survival curves for irradiated cells

    International Nuclear Information System (INIS)

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

  6. 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.

  7. Telomere dysfunction and cell survival: roles for distinctTIN2-containing complexes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sahn-Ho; Davalos, Albert R.; Heo, Seok-Jin; Rodier, Francis; Beausejour, Christian; Kaminker, Patrick; Campisi, Judith

    2006-11-07

    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. These and two other proteins form a soluble complex that may be the core telomere-maintenance complex. It is not clear whether subcomplexes exist or function in vivo. Here, we provide evidence for two TIN2 subcomplexes with distinct functions in human cells. TIN2 ablation by RNA interference caused telomere uncapping and p53-independent cell death in all cells tested. However, we isolated two TIN2 complexes from cell lysates, each selectively sensitive to a TIN2 mutant (TIN2-13, TIN2-15C). 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, TIN215C more than TIN2-13 caused genomic instability and cell death. Thus, TIN2 subcomplexes likely have distinct functions in telomere maintenance, and may provide selective targets for eliminating cells with mutant p53.

  8. Survival and death of endoplasmic-reticulum-stressed cells:Role of autophagy

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Accumulation of unfolded proteins in the endoplasmic reticulum (ER) results in ER stress, which subsequently activates the unfolded protein response that induces a transcriptional program to alleviate the stress. Another cellular process that is activated during ER stress is autophagy, a mechanism of enclosing intracellular compo- nents in a double-membrane autophagosome, and then delivering it to the lysosome for degradation. Here, we discuss the role of autophagy in cellular response to ER stress, the signaling pathways linking ER stress to autophagy, and the possible implication of modulating autophagy in treatment of diseases such as cancer.

  9. Born to be alive: a role for the BCL-2 family in melanoma tumor cell survival, apoptosis, and treatment

    Directory of Open Access Journals (Sweden)

    JerryEdwardChipuk

    2011-10-01

    Full Text Available The global incidence of melanoma has dramatically increased during the recent decades, yet the advancement of primary and adjuvant therapies has not kept a similar pace. The development of melanoma is often centered on cellular signaling that hyper-activates survival pathways, while inducing a concomitant blockade to cell death. Aberrations in cell death signaling not only promote tumor survival and enhanced metastatic potential, but also create resistance to anti-tumor strategies. Chemotherapeutic agents target melanoma tumor cells by inducing a form of cell death called apoptosis, which is governed by the BCL-2 family of proteins. The BCL-2 family is comprised of anti-apoptotic proteins (e.g., BCL-2, BCL-xL, and MCL-1 and pro-apoptotic proteins (e.g., BAK, BAX, and BIM, and their coordinated regulation and function are essential for optimal responses to chemotherapeutics. Here we will discuss what is currently known about the mechanisms of BCL-2 family function with a focus on the signaling pathways that maintain melanoma tumor cell survival. Importantly, we will critically evaluate the literature regarding how chemotherapeutic strategies directly impact on BCL-2 family function and offer several suggestions for future regimens to target melanoma and enhance patient survival.

  10. The role of sphingosine kinase-1 in EGFRvIII-regulated growth and survival of glioblastoma cells

    OpenAIRE

    Estrada-Bernal, Adriana; Lawler, Sean E; Nowicki, Michal O.; Chaudhury, Abhik Ray; Van Brocklyn, James R.

    2010-01-01

    We have previously shown that high expression levels of the lipid kinase sphingosine kinase-1 (SphK1) correlate with poor survival of glioblastoma (GBM) patients. In this study we examined the regulation of SphK1 expression by epidermal growth factor receptor (EGFR) signaling in GBM cells. As the EGFR gene is often overexpressed and mutated in GBM, and EGFR has been shown to regulate SphK1 in some cell types, we examined the effect of EGF signaling and the constitutively active EGFRvIII mutan...

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

    International Nuclear Information System (INIS)

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

  12. Epigenetic Determinants of Erythropoiesis: Role of the Histone Methyltransferase SetD8 in Promoting Erythroid Cell Maturation and Survival.

    Science.gov (United States)

    DeVilbiss, Andrew W; Sanalkumar, Rajendran; Hall, Bryan D R; Katsumura, Koichi R; de Andrade, Isabela Fraga; Bresnick, Emery H

    2015-06-01

    Erythropoiesis, in which committed progenitor cells generate millions of erythrocytes daily, involves dramatic changes in the chromatin structure and transcriptome of erythroblasts, prior to their enucleation. While the involvement of the master-regulatory transcription factors GATA binding protein 1 (GATA-1) and GATA-2 in this process is established, the mechanistic contributions of many chromatin-modifying/remodeling enzymes in red cell biology remain enigmatic. We demonstrated that SetD8, a histone methyltransferase that catalyzes monomethylation of histone H4 at lysine 20 (H4K20me1), is a context-dependent GATA-1 corepressor in erythroid cells. To determine whether SetD8 controls erythroid maturation and/or function, we used a small hairpin RNA (shRNA)-based loss-of-function strategy in a primary murine erythroblast culture system. In this system, SetD8 promoted erythroblast maturation and survival, and this did not involve upregulation of the established regulator of erythroblast survival Bcl-x(L). SetD8 catalyzed H4K20me1 at a critical Gata2 cis element and restricted occupancy by an enhancer of Gata2 transcription, Scl/TAL1, thereby repressing Gata2 transcription. Elevating GATA-2 levels in erythroid precursors yielded a maturation block comparable to that induced by SetD8 downregulation. As lowering GATA-2 expression in the context of SetD8 knockdown did not rescue erythroid maturation, we propose that SetD8 regulation of erythroid maturation involves multiple target genes. These results establish SetD8 as a determinant of erythroid cell maturation and provide a framework for understanding how a broadly expressed histone-modifying enzyme mediates cell-type-specific GATA factor function. PMID:25855754

  13. Survival and patterns of failure in endometrial serous papillary and clear cell carcinoma: role of adjuvant therapy

    International Nuclear Information System (INIS)

    Serous papillary carcinoma (UPSC) and clear-cell carcinoma (CCC) of the endometrium account for only 10% of the total cases of endometrial cancer, yet they represent about 50% of all relapses in endometrial cancer, with a high propensity for extra-pelvic recurrences. Due to a lack of consensus on the best treatment method for these unique but unfavourable subtypes of endometrial cancer, we aim to assess the survival and patterns of failure in patients with UPSC and CCC of the endometrium, and to examine whether adjuvant therapy alters the outcome. Methods and Material: 550 patients underwent primary surgery for their endometrial cancer at King Edward Memorial Hospital between 1991 and 2002. Of these 52 (9.5%) had UPSC or CCC histology. The most common histology was UPSC mixed with endometriod carcinoma (22 cases), followed by UPSC alone (14 cases), then CCC mixed with endometriod carcinoma (11 cases). Surgery was undertaken in all, and majority of patients received para-aortic lymph node biopsy and pelvic lymph node dissection. FIGO staging were as follows: two Stage IA, twenty Stage IB, eight Stage IC, five Stage 2, fourteen Stage 3 and three Stage 4. Adjuvant therapy was as follows: 27 radiotherapy (18 vaginal brachytherapy, 6 external beam pelvic +/- para-aortic radiotherapy, 3 both), 5 chemotherapy (4 alone, 1 with progesterone), 6 hormone alone, and 11 received no treatment. No patient received whole-abdominal radiotherapy. As a group, with a median follow-up of 22 months, the actuarial 5-year overall-survival was 49.6%. Cause-specific survival at 5 year was 60.1%. Stratified by stages, the median overall-survival for Stage 1 was 111 months versus 13 months for all other stages (p<0.0001). Likewise, median survival was not reached for cause-specific survival with Stage 1 patients, but for all other stages it was 15 months (p<0.0001). 35% of patients relapsed, however, only 3 relapsed locally (one also had distant metastases). Most were Stage 2 and above. Of

  14. Role of cumulus cells during vitrification and fertilization of mature bovine oocytes: Effects on survival, fertilization, and blastocyst development.

    Science.gov (United States)

    Ortiz-Escribano, N; Smits, K; Piepers, S; Van den Abbeel, E; Woelders, H; Van Soom, A

    2016-07-15

    This study was designed to determine the role of cumulus cells during vitrification of bovine oocytes. Mature cumulus-oocyte complexes (COCs) with many layers of cumulus cells, corona radiata oocytes (CRs), with a few layers of cumulus cells, and denuded oocytes (DOs) without cumulus cells were vitrified in 15% ethylene glycol, 15% dimethyl sulfoxide, and 0.5-M sucrose. Oocytes that survived the vitrification process were fertilized. Denuded oocytes were fertilized with or without supplementation of intact COCs (DOsCOCs). First, survival and embryo development rates were studied. Higher survival rates were obtained for DOs and DOsCOCs (94% and 95%, respectively) compared with COCs (82.7%, P < 0.05). Corona radiata oocytes showed similar survival rates when compared with DOs. The cleavage and blastocyst rates of vitrified DOs were compromised because cumulus cells were not present during the fertilization (34% and 2.7%, respectively). However, the situation could be reverted when DOs were supplemented with intact COCs (DOsCOCs; 62.7% and 12.7%, respectively, P < 0.05). Vitrified CRs showed similar cleavage and blastocyst rate (49.3% and 7.7%, respectively) compared with COCs (54.8% and 4.9%, respectively). In the second experiment, the penetration rate was analyzed. Removing cumulus cells before fertilization reduced the fertilization of vitrified DOs compared with COCs (24.3% vs. 52.8%, P < 0.05). The supplementation of DOs with intact COCs (DOsCOCs) improved the fertilization rate though (49.6%, P < 0.05). No differences in the fertilization rate were found between CRs and COCs. In the third experiment, parthenogenetic activation was examined. Interestingly, the CRs group showed higher cleavage and blastocyst rates (76.8% and 29.6%, respectively) than the COCs (39.1% and 7.5%, respectively, P < 0.05). Furthermore, oocytes from vitrified CRs had the same odds to become a blastocyst as fresh oocytes (1.1 vs. 1.5, respectively). In conclusion, our data

  15. Significant role of μ-calpain (CANP1) in proliferation/survival of bovine skeletal muscle satellite cells

    OpenAIRE

    Ba, Hoa Van; Inho, Hwang

    2013-01-01

    Calpains are a family of Ca2+-dependent intracellular cysteine proteases, including the ubiquitously expressed μ-calpain (CANP1) and m-calpain (CANP2). The CANP1 has been found to play a central role in postmortem proteolysis and meat tenderization. However, the physiological roles of CANP1 in cattle skeletal satellite cells remain unclear. In this study, three small interference RNA sequences (siRNAs) targeting CANP1 gene were designed and ligated into pSilencer plasmid vector to construct s...

  16. Nrf2 activation supports cell survival during hypoxia and hypoxia/reoxygenation in cardiomyoblasts; the roles of reactive oxygen and nitrogen species

    Directory of Open Access Journals (Sweden)

    Rajitha T Kolamunne

    2013-01-01

    Full Text Available Adaptive mechanisms involving upregulation of cytoprotective genes under the control of transcription factors such as Nrf2 exist to protect cells from permanent damage and dysfunction under stress conditions. Here we explore of the hypothesis that Nrf2 activation by reactive oxygen and nitrogen species modulates cytotoxicity during hypoxia (H with and without reoxygenation (H/R in H9C2 cardiomyoblasts. Using MnTBap as a cell permeable superoxide dismutase (SOD mimetic and peroxynitrite scavenger and L-NAME as an inhibitor of nitric oxide synthase (NOS, we have shown that MnTBap inhibited the cytotoxic effects of hypoxic stress with and without reoxygenation. However, L-NAME only afforded protection during H. Under reoxygenation, conditions, cytotoxicity was increased by the presence of L-NAME. Nrf2 activation was inhibited independently by MnTBap and L-NAME under H and H/R. The increased cytotoxicity and inhibition of Nrf2 activation by the presence of L-NAME during reoxygenation suggests that NOS activity plays an important role in cell survival at least in part via Nrf2-independent pathways. In contrast, O2−• scavenging by MnTBap prevented both toxicity and Nrf2 activation during H and H/R implying that toxicity is largely dependent on O2−·.To confirm the importance of Nrf2 for myoblast metabolism, Nrf2 knockdown with siRNA reduced cell survival by 50% during 4 h hypoxia with and without 2 h of reoxygenation and although cellular glutathione (GSH was depleted during H and H/R, GSH loss was not exacerbated by Nrf2 knockdown. These data support distinctive roles for ROS and RNS during H and H/R for Nrf2 induction which are important for survival independently of GSH salvage.

  17. The extracellular matrix as a cell survival factor.

    OpenAIRE

    Meredith, J E; Fazeli, B; Schwartz, M A

    1993-01-01

    Programmed cell death (PCD) or apoptosis is a naturally occurring cell suicide pathway induced in a variety of cell types. In many cases, PCD is induced by the withdrawal of specific hormones or growth factors that function as survival factors. In this study, we have investigated the potential role of the extracellular matrix (ECM) as a cell survival factor. Our results indicate that in the absence of any ECM interactions, human endothelial cells rapidly undergo PCD, as determined by cell mor...

  18. Role of Cell Cycle Regulation and MLH1, A Key DNA Mismatch Repair Protein, In Adaptive Survival Responses. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    David A. Boothman

    1999-08-11

    Due to several interesting findings on both adaptive survival responses (ASRs) and DNA mismatch repair (MMR), this grant was separated into two discrete Specific Aim sets (each with their own discrete hypotheses). The described experiments were simultaneously performed.

  19. The role of phosphatidylinositol 3-kinase in neural cell adhesion molecule-mediated neuronal differentiation and survival

    DEFF Research Database (Denmark)

    Ditlevsen, Dorte K; Køhler, Lene B; Pedersen, Martin V;

    2003-01-01

    kinase (MAPK) pathway and an increase in intracellular Ca2+ levels. Stimulation of neurones with the synthetic NCAM-ligand, C3, induces neurite outgrowth through signalling pathways similar to the pathways activated through physiological, homophilic NCAM-stimulation. We present here data indicating that...... indicating a survival-promoting effect of NCAM-stimulation by C3 on cerebellar and dopaminergic neurones induced to undergo apoptosis. This protective effect of C3 included an inhibition of both DNA-fragmentation and caspase-3 activation. The survival-promoting effect of NCAM-stimulation was also shown to be...

  20. Role of curcumin-dependent modulation of tumor microenvironment of a murine T cell lymphoma in altered regulation of tumor cell survival

    International Nuclear Information System (INIS)

    Using a murine model of a T cell lymphoma, in the present study, we report that tumor growth retarding action of curcumin involves modulation of some crucial parameters of tumor microenvironment regulating tumor progression. Curcumin-administration to tumor-bearing host caused an altered pH regulation in tumor cells associated with alteration in expression of cell survival and apoptosis regulatory proteins and genes. Nevertheless, an alteration was also observed in biophysical parameters of tumor microenvironment responsible for modulation of tumor growth pertaining to hypoxia, tumor acidosis, and glucose metabolism. The study thus sheds new light with respect to the antineoplastic action of curcumin against a tumor-bearing host with progressively growing tumor of hematological origin. This will help in optimizing application of the drug and anticancer research and therapy. - Graphical Abstract: Display Omitted

  1. Macrophage migration inhibitory factor induces phosphorylation of Mdm2 mediated by phosphatidylinositol 3-kinase/Akt kinase: Role of this pathway in decidual cell survival.

    Science.gov (United States)

    Costa, Adriana Fraga; Gomes, Sara Zago; Lorenzon-Ojea, Aline R; Martucci, Mariane; Faria, Miriam Rubio; Pinto, Décio Dos Santos; Oliveira, Sergio F; Ietta, Francesca; Paulesu, Luana; Bevilacqua, Estela

    2016-05-01

    The phosphatidylinositol 3-kinase (PI3K)/Akt pathway has an anti-apoptotic effect through several downstream targets, which includes activation of the transformed mouse 3T3 cell double-minute 2 (Mdm2) protein, its translocation to the nucleus and degradation of the tumor suppressor p53. We show that Mif, the Macrophage Migration Inhibitory Factor, an important cytokine at the maternal fetal interface in several species, triggers phosphorylation of Mdm2 protein in a PI3K/Akt-dependent manner, thereby preventing apoptosis in cultured mouse decidual cells. Inhibition of Akt and PI3K suppresses the pathway. Mif treatment also changes the nuclear translocation of p53 and interferes with the apoptotic fate of these cells when challenged with reactive oxygen species. In conclusion, an important mechanism has been found underlying decidual cell survival through Akt signaling pathway activated by Mif, suggesting a role for this cytokine in decidual homeostasis and in the integrity of the maternal-fetal barrier that is essential for successful gestation. PMID:27208405

  2. Role of survival post-progression in phase III trials of systemic chemotherapy in advanced non-small-cell lung cancer: a systematic review.

    Directory of Open Access Journals (Sweden)

    Katsuyuki Hotta

    Full Text Available BACKGROUND: In advanced non-small-cell lung cancer (NSCLC, with the increasing number of active compounds available in salvage settings, survival after progression to first-line chemotherapy seems to have improved. A literature survey was conducted to examine whether survival post-progression (SPP has improved over the years and to what degree SPP correlates with overall survival (OS. METHODS AND FINDINGS: Median progression-free survival (MPFS time and median survival time (MST were extracted in phase III trials of first-line chemotherapy for advanced NSCLC. SPP was pragmatically defined as the time interval of MST minus MPFS. The relationship between MPFS and MST was modeled in a linear function. We used the coefficient of determination (r(2 to assess the correlation between them. Seventy trials with 145 chemotherapy arms were identified. Overall, median SPP was 4.7 months, and a steady improvement in SPP was observed over the 20 years (9.414-day increase per year; p<0.001 in parallel to the increase in MST (11.253-day increase per year; p<0.001; MPFS improved little (1.863-day increase per year. Overall, a stronger association was observed between MST and SPP (r(2 = 0.8917 than MST and MPFS time (r(2 = 0.2563, suggesting SPP and MPFS could account for 89% and 25% of the variation in MST, respectively. The association between MST and SPP became closer over the years (r(2 = 0.4428, 0.7242, and 0.9081 in 1988-1994, 1995-2001, and 2002-2007, respectively. CONCLUSIONS: SPP has become more closely associated with OS, potentially because of intensive post-study treatments. Even in advanced NSCLC, a PFS advantage is unlikely to be associated with an OS advantage any longer due to this increasing impact of SPP on OS, and that the prolongation of SPP might limit the original role of OS for assessing true efficacy derived from early-line chemotherapy in future clinical trials.

  3. Losac, a factor X activator from Lonomia obliqua bristle extract: Its role in the pathophysiological mechanisms and cell survival

    International Nuclear Information System (INIS)

    Contact with the bristles of the caterpillar Lonomia obliqua can cause serious hemorrhage. Previously it was reported that a procoagulant protein (Lopap) in the bristle extract of L. obliqua increases cell longevity by inhibiting apoptosis. In this work, we purified from bristle extract a factor X activator that stimulates proliferation of endothelial cells. This protein, named Losac, was purified by ion exchange chromatography, followed by gel filtration chromatography and reverse-phase HPLC. Losac is a 45-kDa protein that activates factor X in a concentration-dependent manner and does not depend on calcium ions. In cultures of HUVECs, Losac increased cell proliferation and inhibited the apoptosis induced by starvation. HUVECs incubated with Losac (0.58 μM for 1 h) increased release of nitric oxide and tissue-plasminogen activator, which both may mediate anti-apoptosis. Losac also increased slightly the decay-accelerating factor (DAF = CD55), which protects cells from complement-mediated lysis. On the other hand, Losac did not alter the release or expression of von Willebrand factor, tissue factor, intercellular adhesion molecule-1, interleukin-8, and prostacyclin. These characteristics indicate that Losac, a protein with procoagulant activity, also functions as a growth stimulator and an inhibitor of cellular death for endothelial cells. Losac may have biotechnological applications, including the reduction of cell death and consequently increased productivity of animal cell cultures, and the use of hemolymph of L. obliqua for this purpose is already being explored. Further study is required to elucidate the mechanism for the inhibition of apoptosis by Losac

  4. The role of phosphatidylinositol 3-kinase in neural cell adhesion molecule-mediated neuronal differentiation and survival

    DEFF Research Database (Denmark)

    Ditlevsen, Dorte K; Køhler, Lene B; Pedersen, Martin Volmer;

    2003-01-01

    phosphatidylinositol 3-kinase (PI3K) is required for NCAM-mediated neurite outgrowth from PC12-E2 cells and from cerebellar and dopaminergic neurones in primary culture, and that the thr/ser kinase Akt/protein kinase B (PKB) is phosphorylated downstream of PI3K after stimulation with C3. Moreover, we present data...

  5. Critical role of astrocytic interleukin-17 A in post-stroke survival and neuronal differentiation of neural precursor cells in adult mice.

    Science.gov (United States)

    Lin, Y; Zhang, J-C; Yao, C-Y; Wu, Y; Abdelgawad, A F; Yao, S-L; Yuan, S-Y

    2016-01-01

    The brain and the immune system interact in complex ways after ischemic stroke, and the long-term effects of immune response associated with stroke remain controversial. As a linkage between innate and adaptive immunity, interleukin-17 A (IL-17 A) secreted from gamma delta (γδ) T cells has detrimental roles in the pathogenesis of acute ischemic stroke. However, to date, the long-term actions of IL-17 A after stroke have not been investigated. Here, we found that IL-17 A showed two distinct peaks of expression in the ischemic hemisphere: the first occurring within 3 days and the second on day 28 after stroke. Our data also showed that astrocyte was the major cellular source of IL-17 A that maintained and augmented subventricular zone (SVZ) neural precursor cells (NPCs) survival, neuronal differentiation, and subsequent synaptogenesis and functional recovery after stroke. IL-17 A also promoted neuronal differentiation in cultured NPCs from the ischemic SVZ. Furthermore, our in vitro data revealed that in primary astrocyte cultures activated astrocytes released IL-17 A via p38 mitogen-activated protein kinase (MAPK). Culture media from reactive astrocytes increased neuronal differentiation of NSCs in vitro. Blockade of IL-17 A with neutralizing antibody prevented this effect. In addition, after screening for multiple signaling pathways, we revealed that the p38 MAPK/calpain 1 signaling pathway was involved in IL-17 A-mediated neurogenesis in vivo and in vitro. Thus, our results reveal a previously uncharacterized property of astrocytic IL-17 A in the maintenance and augment of survival and neuronal differentiation of NPCs, and subsequent synaptogenesis and spontaneous recovery after ischemic stroke. PMID:27336717

  6. Linear and cooperative signaling: roles for Stat proteins in the regulation of cell survival and apoptosis in the mammary epithelium

    International Nuclear Information System (INIS)

    The mammary epithelium undergoes cyclical periods of cellular proliferation, differentiation and regression. These processes are under the control of the hormones secreted during pregnancy, lactation and involution. Signaling pathways have been identified that connect the hormonal stimuli with the transcription of genes responsible for the determination of the cellular fate. The kinetics of induction and deinduction have suggested that cytokine-activated Stat proteins play a crucial role. Stat5 is strongly activated towards the end of pregnancy, persists in an activated state during pregnancy and is rapidly inactivated after cessation of suckling. Stat3 activation is hardly detectable during lactation, but is strongly induced at the onset of involution. The phenotypes of mice in which these genes have been inactivated through homologous recombination corroborate some of the functional assignments deducted from the activation pattern. Stat3 activation seems to be a driving force in the induction of apoptosis early in the involution period

  7. Important Role of FTO in the Survival of Rare Panresistant Triple-Negative Inflammatory Breast Cancer Cells Facing a Severe Metabolic Challenge.

    Science.gov (United States)

    Singh, Balraj; Kinne, Hannah E; Milligan, Ryan D; Washburn, Laura J; Olsen, Mark; Lucci, Anthony

    2016-01-01

    We have previously shown that only 0.01% cells survive a metabolic challenge involving lack of glutamine in culture medium of SUM149 triple-negative Inflammatory Breast Cancer cell line. These cells, designated as SUM149-MA for metabolic adaptability, are resistant to chemotherapeutic drugs, and they efficiently metastasize to multiple organs in nude mice. We hypothesized that obesity-related molecular networks, which normally help in cellular and organismal survival under metabolic challenges, may help in the survival of MA cells. The fat mass and obesity-associated protein FTO is overexpressed in MA cells. Obesity-associated cis-acting elements in non-coding region of FTO regulate the expression of IRX3 gene, thus activating obesity networks. Here we found that IRX3 protein is significantly overexpressed in MA cells (5 to 6-fold) as compared to the parental SUM149 cell line, supporting our hypothesis. We also obtained evidence that additional key regulators of energy balance such as ARID5B, IRX5, and CUX1 P200 repressor could potentially help progenitor-like TNBC cells survive in glutamine-free medium. MO-I-500, a pharmacological inhibitor of FTO, significantly (>90%) inhibited survival and/or colony formation of SUM149-MA cells as compared to untreated cells or those treated with a control compound MO-I-100. Curiously, MO-I-500 treatment also led to decreased levels of FTO and IRX3 proteins in the SUM149 cells initially surviving in glutamine-free medium as compared to MO-I-100 treatment. Interestingly, MO-I-500 treatment had a relatively little effect on cell growth of either the SUM149 or SUM149-MA cell line when added to a complete medium containing glutamine that does not pose a metabolic challenge. Importantly, once selected and cultured in glutamine-free medium, SUM149-MA cells were no longer affected by MO-I-500 even in Gln-free medium. We conclude that panresistant MA cells contain interconnected molecular networks that govern developmental status and

  8. The role of radiation therapy for stage IIIB non-small cell lung cancer. Impact of clinical nodal stage on survival

    International Nuclear Information System (INIS)

    From 1976 through 1989, 46 patients with stage IIIB non-small cell lung cancer (NSCLC) without malignant effusion were treated with definitive radiation therapy (RT) at Gunma University Hospital. All patients were treated with 10 MV x-rays using antero posterior parallel opposed fields. The total dose ranged from 60 Gy to 70 Gy (mean dose; 66 Gy) with once daily standard fractionation. The actuarial two and five-year survival rates of the entire group were 22% and 10% respectively with a median survival time (MST) of 10 months. The survival of 18 patients with stage N0-2 disease was significantly better than the 28 patients with stage N3 disease (MST 21 versus 9 months; p<0.05). There were no significant differences in survival based on age and sex. However, there was a borderline difference in survival rates between patients with a performance status of 0-1 and those with status of 2-3 (p=0.06). Three patients with squamous cell carcinoma were alive after 5 years and were without disease progression. No patients with non-squamous cell carcinoma were free of disease after 5 years. These results provide support for the use of definitive RT to manage those patients with limited stage IIIB squamous cell carcinoma not extending to N3 stage. (author)

  9. The prognostic role of mTOR and p-mTOR for survival in non-small cell lung cancer: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Lei Li

    Full Text Available The mammalian target of rapamycin (mTOR and phosphorylated mTOR (p-mTOR are potential prognostic markers and therapeutic targets for non-small cell lung cancer (NSCLC. However, the association between mTOR/p-mTOR expression and NSCLC patients' prognosis remains controversial. Thus, a meta-analysis of existing studies evaluating the prognostic role of mTOR/p-mTOR expression for NSCLC was conducted.A systemically literature search was performed via Pubmed, Embase, Medline as well as CNKI (China National Knowledge Infrastructure. Studies were included that reported the hazard ratio (HR and 95%CI for the association between mTOR/p-mTOR expression and NSCLC patients' survival. Random-effects model was used to pool HRs.Ten eligible studies were included in this meta-analysis, with 4 about m-TOR and 7 about p-mTOR. For mTOR, the pooled HR of overall survival (OS was 1.00 (95%CI 0.5 to 1.99 by univariate analysis and 1.22 (95%CI 0.53 to 2.82 by multivariate analysis. For p-mTOR, the pooled HR was 1.39 (95%CI 0.97 to 1.98 by univariate analysis and 1.42 (95%CI 0.56 to 3.60 by multivariate analysis.The results indicated that no statistically significant association was found between mTOR/p-mTOR expression and NSCLC patients' prognosis.

  10. MiR-24 promotes the survival of hematopoietic cells.

    Directory of Open Access Journals (Sweden)

    Tan Nguyen

    Full Text Available The microRNA, miR-24, inhibits B cell development and promotes myeloid development of hematopoietic progenitors. Differential regulation of cell survival in myeloid and lymphoid cells by miR-24 may explain how miR-24's affects hematopoietic progenitors. MiR-24 is reported to regulate apoptosis, either positively or negatively depending on cell context. However, no role for miR-24 in regulating cell death has been previously described in blood cells. To examine miR-24's effect on survival, we expressed miR-24 via retrovirus in hematopoietic cells and induced cell death with cytokine or serum withdrawal. We observed that miR-24 enhanced survival of myeloid and B cell lines as well as primary hematopoietic cells. Additionally, antagonizing miR-24 with shRNA in hematopoietic cells made them more sensitive to apoptotic stimuli, suggesting miR-24 functions normally to promote blood cell survival. Since we did not observe preferential protection of myeloid over B cells, miR-24's pro-survival effect does not explain its promotion of myelopoiesis. Moreover, expression of pro-survival protein, Bcl-xL, did not mimic miR-24's impact on cellular differentiation, further supporting this conclusion. Our results indicate that miR-24 is a critical regulator of hematopoietic cell survival. This observation has implications for leukemogenesis. Several miRNAs that regulate apoptosis have been shown to function as either tumor suppressors or oncogenes during leukemogenesis. MiR-24 is expressed highly in primary acute myelogenous leukemia, suggesting that its pro-survival activity could contribute to the transformation of hematopoietic cells.

  11. A1 adenosine receptor-induced phosphorylation and modulation of transglutaminase 2 activity in H9c2 cells: A role in cell survival.

    Science.gov (United States)

    Vyas, Falguni S; Hargreaves, Alan J; Bonner, Philip L R; Boocock, David J; Coveney, Clare; Dickenson, John M

    2016-05-01

    The regulation of tissue transglutaminase (TG2) activity by the GPCR family is poorly understood. In this study, we investigated the modulation of TG2 activity by the A1 adenosine receptor in cardiomyocyte-like H9c2 cells. H9c2 cells were lysed following stimulation with the A1 adenosine receptor agonist N(6)-cyclopentyladenosine (CPA). Transglutaminase activity was determined using an amine incorporating and a protein cross linking assay. TG2 phosphorylation was assessed via immunoprecipitation and Western blotting. The role of TG2 in A1 adenosine receptor-induced cytoprotection was investigated by monitoring hypoxia-induced cell death. CPA induced time and concentration-dependent increases in amine incorporating and protein crosslinking activity of TG2. CPA-induced increases in TG2 activity were attenuated by the TG2 inhibitors Z-DON and R283. Responses to CPA were blocked by PKC (Ro 31-8220), MEK1/2 (PD 98059), p38 MAPK (SB 203580) and JNK1/2 (SP 600125) inhibitors and by removal of extracellular Ca(2+). CPA triggered robust increases in the levels of TG2-associated phosphoserine and phosphothreonine, which were attenuated by PKC, MEK1/2 and JNK1/2 inhibitors. Fluorescence microscopy revealed TG2-mediated biotin-X-cadaverine incorporation into proteins and proteomic analysis identified known (Histone H4) and novel (Hexokinase 1) protein substrates for TG2. CPA pre-treatment reversed hypoxia-induced LDH release and decreases in MTT reduction. TG2 inhibitors R283 and Z-DON attenuated A1 adenosine receptor-induced cytoprotection. TG2 activity was stimulated by the A1 adenosine receptor in H9c2 cells via a multi protein kinase dependent pathway. These results suggest a role for TG2 in A1 adenosine receptor-induced cytoprotection. PMID:27005940

  12. 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.

  13. BAP1 has a survival role in cutaneous melanoma.

    Science.gov (United States)

    Kumar, Raj; Taylor, Michael; Miao, Benchun; Ji, Zhenyu; Njauw, Jenny C-N; Jönsson, Göran; Frederick, Dennie T; Tsao, Hensin

    2015-04-01

    Although the pattern of BAP1 inactivation in ocular melanoma specimens and in the BAP1 cutaneous melanoma (CM)/ocular melanoma predisposition syndrome suggests a tumor suppressor function, the specific role of this gene in the pathogenesis of CM is not fully understood. We thus set out to characterize BAP1 in CM and discovered an unexpected pro-survival effect of this protein. Tissue and cell lines analysis showed that BAP1 expression was maintained, rather than lost, in primary melanomas compared with nevi and normal skin. Genetic depletion of BAP1 in melanoma cells reduced proliferation and colony-forming capability, induced apoptosis, and inhibited melanoma tumor growth in vivo. On the molecular level, suppression of BAP1 led to a concomitant drop in the protein levels of survivin, a member of anti-apoptotic proteins and a known mediator of melanoma survival. Restoration of survivin in melanoma cells partially rescued the growth-retarding effects of BAP1 loss. In contrast to melanoma cells, stable overexpression of BAP1 into immortalized but non-transformed melanocytes did suppress proliferation and reduce survivin. Taken together, these studies demonstrate that BAP1 may have a growth-sustaining role in melanoma cells, but that its impact on ubiquitination underpins a complex physiology, which is context and cell dependent. PMID:25521456

  14. Cell therapy for Parkinson׳s disease: Functional role of the host immune response on survival and differentiation of dopaminergic neuroblasts.

    Science.gov (United States)

    Wenker, Shirley D; Leal, María Celeste; Farías, María Isabel; Zeng, Xianmin; Pitossi, Fernando J

    2016-05-01

    Parkinson׳s disease (PD) is a neurodegenerative disorder, whose cardinal pathology is the loss of dopaminergic neurons in the substantia nigra. Current treatments for PD have side effects in the long term and do not halt disease progression or regenerate dopaminergic cell loss. Attempts to compensate neuronal cell loss by transplantation of dopamine-producing cells started more than 30 years ago, leading to several clinical trials. These trials showed safety and variable efficacy among patients. In addition to variability in efficacy, several patients developed graft-induced dyskinesia. Nevertheless, they have provided a proof of concept that motor symptoms could be improved by cell transplantation. Cell transplantation in the brain presents several immunological challenges. The adaptive immune response should be abolished to avoid graft rejection by the host. In addition, the innate immune response will always be present after transplanting cells into the brain. Remarkably, the innate immune response can have dramatic effects on the survival, differentiation and proliferation of the transplanted cells, but has been hardly investigated. In this review, we analyze data on the functional effects of signals from the innate immune system on dopaminergic differentiation, survival and proliferation. Then, we discussed efforts on cell transplantation in animal models and PD patients, highlighting the immune response and the immunomodulatory treatment strategies performed. The analysis of the available data lead us to conclude that the modulation of the innate immune response after transplantation can increase the success of future clinical trials in PD by enhancing cell differentiation and survival. This article is part of a Special Issue entitled SI: PSC and the brain. PMID:26239914

  15. Nerve Growth Factor in Cancer Cell Death and Survival

    International Nuclear Information System (INIS)

    One of the major challenges for cancer therapeutics is the resistance of many tumor cells to induction of cell death due to pro-survival signaling in the cancer cells. Here we review the growing literature which shows that neurotrophins contribute to pro-survival signaling in many different types of cancer. In particular, nerve growth factor, the archetypal neurotrophin, has been shown to play a role in tumorigenesis over the past decade. Nerve growth factor mediates its effects through its two cognate receptors, TrkA, a receptor tyrosine kinase and p75NTR, a member of the death receptor superfamily. Depending on the tumor origin, pro-survival signaling can be mediated by TrkA receptors or by p75NTR. For example, in breast cancer the aberrant expression of nerve growth factor stimulates proliferative signaling through TrkA and pro-survival signaling through p75NTR. This latter signaling through p75NTR promotes increased resistance to the induction of cell death by chemotherapeutic treatments. In contrast, in prostate cells the p75NTR mediates cell death and prevents metastasis. In prostate cancer, expression of this receptor is lost, which contributes to tumor progression by allowing cells to survive, proliferate and metastasize. This review focuses on our current knowledge of neurotrophin signaling in cancer, with a particular emphasis on nerve growth factor regulation of cell death and survival in cancer

  16. Modulation of cell proliferation, survival and gene expression by RAGE and TLR signaling in cells of the innate and adaptive immune response: role of p38 MAPK and NF-KB

    Science.gov (United States)

    de MEDEIROS, Marcell Costa; FRASNELLI, Sabrina Cruz Tfaile; BASTOS, Alliny de Souza; ORRICO, Silvana Regina Perez; ROSSA JUNIOR, Carlos

    2014-01-01

    Objective The aim of this study was to evaluate a possible synergism between AGE-RAGE and TLR4 signaling and the role of p38 MAPK and NF-kB signaling pathways on the modulation of the expression of inflammatory cytokines and proliferation of cells from the innate and adaptive immune response. Material and Methods T lymphocyte (JM) and monocyte (U937) cell lines were stimulated with LPS and AGE-BSA independently and associated, both in the presence and absence of p38 MAPK and NF-kB inhibitors. Proliferation was assessed by direct counting and viability was assessed by a biochemical assay of mitochondrial function. Cytokine gene expression for RAGe, CCL3, CCR5, IL-6 and TNF-α was studied by RT-PCR and RT-qPCR. Results RAGE mRNA expression was detected in both cell lines. LPS and AGE-BSA did not influence cell proliferation and viability of either cell line up to 72 hours. LPS and LPS associated with AGE induced expression of IL-6 and TNF-α in monocytes and T cells, respectively. Conclusions There is no synergistic effect between RAGE and TLR signaling on the expression of IL-6, TNF-α , RAGE, CCR5 and CCL3 by monocytes and lymphocytes. Activation of RAGE associated or not with TLR signaling also had no effect on cell proliferation and survival of these cell types. PMID:25025559

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-11-15

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

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

    International Nuclear Information System (INIS)

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

  19. Properties of Lewis Lung Carcinoma Cells Surviving Curcumin Toxicity

    Directory of Open Access Journals (Sweden)

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

    2012-01-01

    Full Text Available 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.

  20. Mitochondrial genome depletion in human liver cells abolishes bile acid-induced apoptosis: role of the Akt/mTOR survival pathway and Bcl-2 family proteins.

    Science.gov (United States)

    Marin, Jose J G; Hernandez, Alicia; Revuelta, Isabel E; Gonzalez-Sanchez, Ester; Gonzalez-Buitrago, Jose M; Perez, Maria J

    2013-08-01

    Acute accumulation of bile acids in hepatocytes may cause cell death. However, during long-term exposure due to prolonged cholestasis, hepatocytes may develop a certain degree of chemoresistance to these compounds. Because mitochondrial adaptation to persistent oxidative stress may be involved in this process, here we have investigated the effects of complete mitochondrial genome depletion on the response to bile acid-induced hepatocellular injury. A subline (Rho) of human hepatoma SK-Hep-1 cells totally depleted of mitochondrial DNA (mtDNA) was obtained, and bile acid-induced concentration-dependent activation of apoptosis/necrosis and survival signaling pathways was studied. In the absence of changes in intracellular ATP content, Rho cells were highly resistant to bile acid-induced apoptosis and partially resistant to bile acid-induced necrosis. In Rho cells, both basal and bile acid-induced generation of reactive oxygen species (ROS), such as hydrogen peroxide and superoxide anion, was decreased. Bile acid-induced proapoptotic signals were also decreased, as evidenced by a reduction in the expression ratios Bax-α/Bcl-2, Bcl-xS/Bcl-2, and Bcl-xS/Bcl-xL. This was mainly due to a downregulation of Bax-α and Bcl-xS. Moreover, in these cells the Akt/mTOR pathway was constitutively activated in a ROS-independent manner and remained similarly activated in the presence of bile acid treatment. In contrast, ERK1/2 activation was constitutively reduced and was not activated by incubation with bile acids. In conclusion, these results suggest that impaired mitochondrial function associated with mtDNA alterations, which may occur in liver cells during prolonged cholestasis, may activate mechanisms of cell survival accounting for an enhanced resistance of hepatocytes to bile acid-induced apoptosis. PMID:23597504

  1. The role of circulating anti-p53 antibodies in patients with advanced non-small cell lung cancer and their correlation to clinical parameters and survival

    International Nuclear Information System (INIS)

    Lung cancer causes approximately one million deaths each year worldwide and protein p53 has been shown to be involved in the intricate processes regulating response to radiation and/or chemotherapeutic treatment. Consequently, since antibodies against p53 (anti-p53 antibodies) are associated with mutations within the p53 gene it seems likely that these antibodies could, hypothetically, be correlated with prognosis. Serum samples from patients with non-small cell lung cancer (NSCLC) admitted to the Department of Oncology, University Hospital, Uppsala, Sweden, during 1983–1996 were studied. Anti-p53 abs were measured using a sandwich ELISA (Dianova, Hamburg, Germany). The present study included 84 patients with stage IIIA-IV (advanced NSCLC). At least three serum samples from each patient were collected and altogether 529 serum samples were analysed for the presence of anti-p53 antibodies. The median value of anti-p53 antibodies was 0.06 (range 0 – 139.8). Seventeen percent of investigated NSCLC first serum samples (n = 84) expressed elevated levels of anti-p53 antibodies. Anti-p53 antibodies were not correlated to tumour volume or platelets. Survival analysis showed that anti-p53 antibodies were not associated with survival as revealed by univariate analysis (p = 0.29). However, patients with adenocarcinoma had a significantly poorer survival if they expressed anti-p53 antibodies (p = 0.01), whereas this was not found for patients with squamous cell carcinoma (p = 0.13). In patients where the blood samples were collected during radiation therapy, a statistically significant correlation towards poorer survival was found (p = 0.05) when elevated anti-p53 antibodies levels were present. No correlations to survival were found for serum samples collected prior to radiation therapy, during chemotherapy, or during follow-up. When anti-p53 antibodies were measured continuously, no increase in median anti-p53 values was observed the closer the individual patient come to

  2. Platelets increase survival of adenocarcinoma cells challenged with anticancer drugs: mechanisms and implications for chemoresistance.

    OpenAIRE

    Radomski, Marek; MEDINA MARTIN, CARLOS; O'Driscoll, Lorraine

    2012-01-01

    PUBLISHED BACKGROUND AND PURPOSE: Cancer cells grow without the restraints of feedback control mechanisms, leading to increased cancer cell survival. The treatment of cancer is often complicated by the lack of response to chemotherapy leading to chemoresistance and persistent survival of tumour cells. In this work we studied the role of platelets in chemotherapy-induced cancer cell death and survival. EXPERIMENTAL APPROACH: Human adenocarcinoma cells, colonic (Caco-2) and ovaria...

  3. Cell survival studies for moving targets

    International Nuclear Information System (INIS)

    More than 330 patients with static tumors have been treated at GSI with a scanned C-12 beam. For targets that are subject to respiratory motion, treatment is not yet possible because target motion and scanning motion interfere. GSI is developing a motion compensation system to compensate target motion by adaptation of each individual Bragg peak position. Within this project, the GSI treatment planning software TRiP was extended to calculate physical dose distributions in the presence of motion. These motion extensions were experimentally validated. Recently we included the calculation of cell survival for moving targets. To validate the software, a program of experimental studies with biological samples has been started. In a first set of experiments, living cell cultures were placed on a periodically moving table and irradiated with and without motion compensation. Results are compared to reference cell cultures that were static during standard irradiations. Furthermore, measured cell survival distributions are compared to calculated distributions for all irradiation schemes

  4. Erythropoietin signaling promotes transplanted progenitor cell survival

    OpenAIRE

    Jia, Yi; Warin, Renaud; Yu, Xiaobing; Epstein, Reed; Noguchi, Constance Tom

    2009-01-01

    We examine the potential for erythropoietin signaling to promote donor cell survival in a model of myoblast transplantation. Expression of a truncated erythropoietin receptor in hematopoietic stem cells has been shown to promote selective engraftment in mice. We previously demonstrated expression of endogenous erythropoietin receptor on murine myoblasts, and erythropoietin treatment can stimulate myoblast proliferation and delay differentiation. Here, we report that enhanced erythropoietin re...

  5. Role of Cathepsins in Mycobacterium tuberculosis Survival in Human Macrophages.

    Science.gov (United States)

    Pires, David; Marques, Joana; Pombo, João Palma; Carmo, Nuno; Bettencourt, Paulo; Neyrolles, Olivier; Lugo-Villarino, Geanncarlo; Anes, Elsa

    2016-01-01

    Cathepsins are proteolytic enzymes that function in the endocytic pathway, especially in lysosomes, where they contribute directly to pathogen killing or indirectly, by their involvement in the antigen presentation pathways. Mycobacterium tuberculosis (MTB) is a facultative intracellular pathogen that survives inside the macrophage phagosomes by inhibiting their maturation to phagolysosomes and thus avoiding a low pH and protease-rich environment. We previously showed that mycobacterial inhibition of the proinflammatory transcription factor NF-κB results in impaired delivery of lysosomal enzymes to phagosomes and reduced pathogen killing. Here, we elucidate how MTB also controls cathepsins and their inhibitors, cystatins, at the level of gene expression and proteolytic activity. MTB induced a general down-regulation of cathepsin expression in infected cells, and inhibited IFNγ-mediated increase of cathepsin mRNA. We further show that a decrease in cathepsins B, S and L favours bacterial survival within human primary macrophages. A siRNA knockdown screen of a large set of cathepsins revealed that almost half of these enzymes have a role in pathogen killing, while only cathepsin F coincided with MTB resilience. Overall, we show that cathepsins are important for the control of MTB infection, and as a response, it manipulates their expression and activity to favour its intracellular survival. PMID:27572605

  6. Cell survival studies using ultrasoft x rays

    International Nuclear Information System (INIS)

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

  7. p63 promotes cell survival through fatty acid synthase.

    Directory of Open Access Journals (Sweden)

    Venkata Sabbisetti

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

  8. 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

  9. TRAIL treatment provokes mutations in surviving cells

    OpenAIRE

    Lovric, M M; Hawkins, C J

    2010-01-01

    Chemotherapy and radiotherapy commonly damage DNA and trigger p53-dependent apoptosis through intrinsic apoptotic pathways. Two unfortunate consequences of this mechanism are resistance due to blockade of p53 or intrinsic apoptosis pathways, and mutagenesis of non-malignant surviving cells which can impair cellular function or provoke second malignancies. Death ligand-based drugs, such as tumor necrosis factor-related apoptosis inducing ligand (TRAIL), stimulate extrinsic apoptotic signaling,...

  10. Cytokine signaling for proliferation, survival, and death in hematopoietic cells.

    Science.gov (United States)

    Miyajima, A; Ito, Y; Kinoshita, T

    1999-04-01

    The survival, proliferation, and differentiation of hematopoietic cells are regulated by cytokines. In the absence of cytokines, hematopoietic cells not only stop proliferation, but undergo apoptosis. This strict dependency of hematopoietic cells on cytokines is an important mechanism that maintains the homeostasis of blood cells. Cytokines induce various intracellular signaling pathways by activating the receptor-associated Janus kinases (Jaks), and distinct signals are responsible for cell cycle progression and cell survival. Induction of signals for cell cycle progression without suppressing apoptosis results in apoptotic cell death, indicating the essential role of anti-apoptotic signaling for cell growth. In hematopoietic cells, Ras, a cellular protooncogen product, and phosphatidylinositol 3 kinase are involved in the suppression of apoptosis. Cytokine depletion not only turns off anti-apoptotic signaling, but also actively induces cell death by activating caspases, a distinct family of cysteine proteases. Alterations in the mechanisms of cytokine signaling for cell cycle progression and anti-apoptotic function are implicated in hematological disorders. PMID:10222650

  11. Novel roles of the Na+/H+ exchanger NHE1 and the Na+,HCO3 - cotransporter NBCn1 in cell survival, proliferation and motility

    DEFF Research Database (Denmark)

    Thorup, Gitte Ehrenreich

    cell motility. The molecular mechanisms contributing to altered pHi regulation in cancer cells are incomplete understood. Overexpression of ErbB2 is common in breast cancer and the expression of an N-terminally truncated, constitutively active ErbB2 receptor (ΔNErbB2) is associated with increased...... glycolysis, malignancy and poor prognosis. This thesis focuses on the regulation and roles of two pH regulatory transporters, the Na+/H+ exchanger NHE1 (SLC9A1) and the Na+,HCO3 - cotransporter NBCn1 (SLC4A7) in MCF-7 breast cancer cells expressing ΔNErbB2. Specifically, how these transporters contribute to....... Pharmacological inhibition of NHE1 enhances cisdiamminedichloroplatinum (II) (cisplatin) induced cell death, especially in ΔNErbB2 expressing cells. In Paper III we show that upon cisplatin treatment, expression of ΔNErbB2 results in increased caspase-9 and -7 cleavage, which is further augmented by specific...

  12. AKT Inhibition Promotes Nonautonomous Cancer Cell Survival.

    Science.gov (United States)

    Salony; Solé, Xavier; Alves, Cleidson P; Dey-Guha, Ipsita; Ritsma, Laila; Boukhali, Myriam; Lee, Ju H; Chowdhury, Joeeta; Ross, Kenneth N; Haas, Wilhelm; Vasudevan, Shobha; Ramaswamy, Sridhar

    2016-01-01

    Small molecule inhibitors of AKT (v-akt murine thymoma viral oncogene homolog) signaling are being evaluated in patients with various cancer types, but have so far proven therapeutically disappointing for reasons that remain unclear. Here, we treat cancer cells with subtherapeutic doses of Akti-1/2, an allosteric small molecule AKT inhibitor, in order to experimentally model pharmacologic inhibition of AKT signaling in vitro. We then apply a combined RNA, protein, and metabolite profiling approach to develop an integrated, multiscale, molecular snapshot of this "AKT(low)" cancer cell state. We find that AKT-inhibited cancer cells suppress thousands of mRNA transcripts, and proteins related to the cell cycle, ribosome, and protein translation. Surprisingly, however, these AKT-inhibited cells simultaneously upregulate a host of other proteins and metabolites posttranscriptionally, reflecting activation of their endo-vesiculo-membrane system, secretion of inflammatory proteins, and elaboration of extracellular microvesicles. Importantly, these microvesicles enable rapidly proliferating cancer cells of various types to better withstand different stress conditions, including serum deprivation, hypoxia, or cytotoxic chemotherapy in vitro and xenografting in vivo. These findings suggest a model whereby cancer cells experiencing a partial inhibition of AKT signaling may actually promote the survival of neighbors through non-cell autonomous communication. PMID:26637368

  13. PROGNOSTIC FACTORS IN PATIENTS WITH RENAL-CELL CARCINOMA AND A ROLE OF ONCOPHAGE IN INCREASING SURVIVAL RATES AFTER SURGICAL TREATMENT

    Directory of Open Access Journals (Sweden)

    B. Ya. Alekseyev

    2014-08-01

    Full Text Available The prognostic value of the Fuhrman renal-cell carcinoma (RCC gradation system has been supported by numerous studies. The high RCC  grade after Fuhrman is a sign of the high risk of recurrence even in patients with the early stages of the disease, in clear-cell tumor in par-  ticular. The anticancer vaccine Oncophage is recommended to prevent a recurrence and/or to increase a relapse-free period in patients with  early stages of RCC. While using this vaccine, one should follow the Fuhrman histological gradation system and use a coordinated multi-  disciplinary approach to treating this group of patients. This paper describes the Fuhrman histological gradation system, indications for the  use of Oncophage in patients with the early stages of ECC and a moderate risk of a recurrence. The role of urological surgeons, oncologists,  and pathomorphologists in the treatment of patients with early stages of ECC is also considered.    

  14. B-cell survival factors in autoimmune rheumatic disorders

    Science.gov (United States)

    Morais, Sandra A.; Vilas-Boas, Andreia

    2015-01-01

    Autoimmune rheumatic disorders have complex etiopathogenetic mechanisms in which B cells play a central role. The importance of factors stimulating B cells, notably the B-cell activating factor (BAFF) and A proliferation inducing ligand (APRIL) axis is now recognized. BAFF and APRIL are cytokines essential for B-cell proliferation and survival from the immature stages to the development of plasma cells. Their levels are increased in some subsets of patients with autoimmune disorders. Several recent biologic drugs have been developed to block this axis, namely belimumab [already licensed for systemic lupus erythematosus (SLE) treatment], tabalumab, atacicept and blisibimod. Many clinical trials to evaluate the safety and efficacy of these drugs in several autoimmune disorders are ongoing, or have been completed recently. This review updates the information on the use of biologic agents blocking BAFF/APRIL for patients with SLE, rheumatoid arthritis, Sjögren’s syndrome and myositis. PMID:26288664

  15. IGFBP2 promotes glioma tumor stem cell expansion and survival

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, David, E-mail: dhs.zfs@gmail.com [College of Medicine, The University of Arizona (United States); Hsieh, Antony [The McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine (United States); Stea, Baldassarre [Department of Radiation Oncology, The University of Arizona (United States); Ellsworth, Ron [College of Medicine, The University of Arizona (United States)

    2010-06-25

    IGFBP2 is overexpressed in the most common brain tumor, glioblastoma (GBM), and its expression is inversely correlated to GBM patient survival. Previous reports have demonstrated a role for IGFBP2 in glioma cell invasion and astrocytoma development. However, the function of IGFBP2 in the restricted, self-renewing, and tumorigenic GBM cell population comprised of tumor-initiating stem cells has yet to be determined. Herein we demonstrate that IGFBP2 is overexpressed within the stem cell compartment of GBMs and is integral for the clonal expansion and proliferative properties of glioma stem cells (GSCs). In addition, IGFBP2 inhibition reduced Akt-dependent GSC genotoxic and drug resistance. These results suggest that IGFBP2 is a selective malignant factor that may contribute significantly to GBM pathogenesis by enriching for GSCs and mediating their survival. Given the current dearth of selective molecular targets against GSCs, we anticipate our results to be of high therapeutic relevance in combating the rapid and lethal course of GBM.

  16. 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...... regulatory circuits. This review highlights some of the connections between opposite-acting pathways. Thus, we discuss the role of cyclins in the apoptotic process, and in the regulation of cell proliferation. CDKs and their inhibitors like the INK4-family (p16(Ink4a), p15(Ink4b), p18(Ink4c), p19(Ink4d...... highlighted 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...

  17. The role of caspase 3 and BclxL in the action of interleukin 7 (IL-7): a survival factor in activated human T cells

    DEFF Research Database (Denmark)

    Amos, C L; Woetmann, A; Nielsen, M;

    1998-01-01

    The effects of interleukin 7 (IL-7) on apoptosis in interleukin 2 (IL-2)-dependent, activated, primary, human T lymphocytes (hT cells) was examined. IL-7 (like IL-2) rescued cells from apoptosis, as measured by their cellular DNA profile and fragmentation. IL-2 also acted as a mitogen in these T ...

  18. The role of C/EBPa in PD-1+ CD4+ T cells & modulation of RNR activity prolongs survival of mice with AML

    DEFF Research Database (Denmark)

    Norrie, Ida Christine

    young PD-1+ CD4+ T cells, suggesting that C/EBPα repress the accumulation of these cells in old mice. Furthermore, C/EBPα-deficiency in the lymphoid compartment had no effect on leukemic development and did not affect the accumulation of PD-1+ CD4+ T cells during development of leukemia. M data...... development. Expression of Sml1 in transplanted MLL-AF9 cells had no effect on the latency. The distribution of myeloid lineage cells in the MLL-AF9-induced acute myeloid leukemias was not changed by overexpression of R2, or expression of Dif1 or Sml1. However, overexpression of R2b resulted in a more...... and decreased proliferation. Fu rthermore, the amount of C/EBPα-expressing PD-1+ CD4+ T cells is increased during the development of leukemia, where they might account for the depressed T cell immuno-response that arises during development of disease. The importance of C/EBPα expression for the...

  19. Properties of Lewis Lung Carcinoma Cells Surviving Curcumin Toxicity

    OpenAIRE

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

    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 establis...

  20. 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

  1. 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. PMID:27112509

  2. Gene Network Analysis of Glucose Linked Signaling Pathways and Their Role in Human Hepatocellular Carcinoma Cell Growth and Survival in HuH7 and HepG2 Cell Lines

    Directory of Open Access Journals (Sweden)

    Emmanuelle Berger

    2015-01-01

    Full Text Available Cancer progression may be affected by metabolism. In this study, we aimed to analyze the effect of glucose on the proliferation and/or survival of human hepatocellular carcinoma (HCC cells. Human gene datasets regulated by glucose were compared to gene datasets either dysregulated in HCC or regulated by other signaling pathways. Significant numbers of common genes suggested putative involvement in transcriptional regulations by glucose. Real-time proliferation assays using high (4.5 g/L versus low (1 g/L glucose on two human HCC cell lines and specific inhibitors of selected pathways were used for experimental validations. High glucose promoted HuH7 cell proliferation but not that of HepG2 cell line. Gene network analyses suggest that gene transcription by glucose could be mediated at 92% through ChREBP in HepG2 cells, compared to 40% in either other human cells or rodent healthy liver, with alteration of LKB1 (serine/threonine kinase 11 and NOX (NADPH oxidases signaling pathways and loss of transcriptional regulation of PPARGC1A (peroxisome-proliferator activated receptors gamma coactivator 1 target genes by high glucose. Both PPARA and PPARGC1A regulate transcription of genes commonly regulated by glycolysis, by the antidiabetic agent metformin and by NOX, suggesting their major interplay in the control of HCC progression.

  3. FoxO1a and SIRT1 in vasculo-proliferative diseases : Major roles in regulating smooth muscle cell proliferation, migration and survival

    OpenAIRE

    König, Heike

    2009-01-01

    Vasculo-proliferative disorders such as atherosclerosis, postangioplasty restenosis, and pulmonary hypertension are complex processes that are especially related to vascular smooth muscle cells (VSMCs)45, 78. In the arterial media, VSMC are normally quiescent, however, for the development and progression of the above mentioned diseases it is prerequisite that quiescent VSMCs start to proliferate, migrate and undergo apoptosis. Different extracellular stimuli are responsible for regulating VSM...

  4. Physical Interaction of Jab1 with Human Serotonin 6 G-protein-coupled Receptor and Their Possible Roles in Cell Survival*

    OpenAIRE

    Yun, Hyung-Mun; Baik, Ja-Hyun; Kang, Insug; Jin, Changbae; Rhim, Hyewhon

    2010-01-01

    The 5-HT6 receptor (5-HT6R) is one of the most recently cloned serotonin receptors, and it plays important roles in Alzheimer disease, depression, and learning and memory disorders. However, unlike the other serotonin receptors, the cellular mechanisms of 5-HT6R are poorly elucidated relative to its significance in human brain diseases. Here, using a yeast two-hybrid assay, we found that the human 5-HT6R interacts with Jun activation domain-binding protein-1 (Jab1). We also confirmed a physic...

  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. Brief report: a human induced pluripotent stem cell model of cernunnos deficiency reveals an important role for XLF in the survival of the primitive hematopoietic progenitors.

    Science.gov (United States)

    Tilgner, Katarzyna; Neganova, Irina; Singhapol, Chatchawan; Saretzki, Gabriele; Al-Aama, Jumana Yousuf; Evans, Jerome; Gorbunova, Vera; Gennery, Andrew; Przyborski, Stefan; Stojkovic, Miodrag; Armstrong, Lyle; Jeggo, Penny; Lako, Majlinda

    2013-09-01

    Cernunnos (also known as XLF) deficiency syndrome is a rare recessive autosomal disorder caused by mutations in the XLF gene, a key factor involved in the end joining step of DNA during nonhomologous end joining (NHEJ) process. Human patients with XLF mutations display microcephaly, developmental and growth delays, and severe immunodeficiency. While the clinical phenotype of DNA damage disorders, including XLF Syndrome, has been described extensively, the underlying mechanisms of disease onset, are as yet, undefined. We have been able to generate an induced pluripotent stem cell (iPSC) model of XLF deficiency, which accurately replicates the double-strand break repair deficiency observed in XLF patients. XLF patient-specific iPSCs (XLF-iPSC) show typical expression of pluripotency markers, but have altered in vitro differentiation capacity and an inability to generate teratomas comprised of all three germ layers in vivo. Our results demonstrate that XLF-iPSCs possess a weak NHEJ-mediated DNA repair capacity that is incapable of coping with the DNA lesions introduced by physiological stress, normal metabolism, and ionizing radiation. XLF-iPSC lines are capable of hematopoietic differentiation; however, the more primitive subsets of hematopoietic progenitors display increased apoptosis in culture and an inability to repair DNA damage. Together, our findings highlight the importance of NHEJ-mediated-DNA repair in the maintenance of a pristine pool of hematopoietic progenitors during human embryonic development. PMID:23818183

  7. Epithelial cell invasion and survival of Bordetella bronchiseptica.

    OpenAIRE

    SCHIPPER, H; Krohne, G F; R. Gross

    1994-01-01

    Wild-type Bordetella bronchiseptica and a bvg mutant strain were used for invasion and survival experiments in human Caco-2 and A549 epithelial cells. Both bacterial strains were able to enter and persist within the host cells for at least a week. A significant proportion of the bacteria from both B. bronchiseptica strains but not from Bordetella pertussis were found free in the cytoplasm, suggesting different invasion and survival strategies of the two species in epithelial cells.

  8. The unfinished child survival revolution: the role of nutrition

    OpenAIRE

    Persson, Lars-Åke

    2005-01-01

    Since an impressive reduction in child mortality in the 1970s to early 1990s improvements have slowed down, and more than 10 million children die annually under the age of 5 years. Most of these deaths occur in relatively few countries, mainly in South Asia and Africa south of the Sahara. Given the causal links between nutrition and mortality in infancy and childhood it is of great importance to assess the role of nutrition in further improvements in global child survival. This study assessed...

  9. A statistical model for red blood cell survival.

    Science.gov (United States)

    Korell, Julia; Coulter, Carolyn V; Duffull, Stephen B

    2011-01-01

    A statistical model for the survival time of red blood cells (RBCs) with a continuous distribution of cell lifespans is presented. The underlying distribution of RBC lifespans is derived from a probability density function with a bathtub-shaped hazard curve, and accounts for death of RBCs due to senescence (age-dependent increasing hazard rate) and random destruction (constant hazard), as well as for death due to initial or delayed failures and neocytolysis (equivalent to early red cell mortality). The model yields survival times similar to those of previously published studies of RBC survival and is easily amenable to inclusion of drug effects and haemolytic disorders. PMID:20950630

  10. Atypical protein kinase C zeta: potential player in cell survival and cell migration of ovarian cancer.

    Directory of Open Access Journals (Sweden)

    Kelly K Y Seto

    Full Text Available Ovarian cancer is one of the most aggressive gynaecological cancers, thus understanding the different biological pathways involved in ovarian cancer progression is important in identifying potential therapeutic targets for the disease. The aim of this study was to investigate the potential roles of Protein Kinase C Zeta (PRKCZ in ovarian cancer. The atypical protein kinase C isoform, PRKCZ, is involved in the control of various signalling processes including cell proliferation, cell survival, and cell motility, all of which are important for cancer development and progression. Herein, we observe a significant increase in cell survival upon PRKCZ over-expression in SKOV3 ovarian cancer cells; additionally, when the cells are treated with small interference RNA (siRNA targeting PRKCZ, the motility of SKOV3 cells decreased. Furthermore, we demonstrate that over-expression of PRKCZ results in gene and/or protein expression alterations of insulin-like growth factor 1 receptor (IGF1R and integrin beta 3 (ITGB3 in SKOV3 and OVCAR3 cells. Collectively, our study describes PRKCZ as a potential regulatory component of the IGF1R and ITGB3 pathways and suggests that it may play critical roles in ovarian tumourigenesis.

  11. Assessment of pancreatic islet cell function and survival

    OpenAIRE

    Köhler, Martin

    2015-01-01

    Function and survival of pancreatic islet insulin-producing beta-cells (β-cells) and glucagonproducing alpha-cells (α-cells) were studied, and methods for this purpose were developed or refined. Dynamic control of glucose metabolism is essential for β-cell stimulus-secretion coupling. ATP is an important metabolic parameter and therefore we set up a technique to monitor dynamic changes of ATP in insulin-producing cells using luciferase bioluminescence at the level of single...

  12. Properties of Lewis Lung Carcinoma Cells Surviving Curcumin Toxicity

    OpenAIRE

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

    2011-01-01

    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 ce...

  13. 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

  14. 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.

  15. HSP70 mediates survival in apoptotic cells – Boolean network prediction and experimental validation

    Directory of Open Access Journals (Sweden)

    Suhas Vasaikar

    2015-08-01

    Full Text Available Neuronal stress or injury results in the activation of proteins, which regulate the balance between survival and apoptosis. However, the complex mechanism of cell signalling 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 towards 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 expression 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 towards 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-fold, 1.26-fold 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.

  16. 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.

  17. Survival and innovation: The role of mutational robustness in evolution.

    Science.gov (United States)

    Fares, Mario A

    2015-12-01

    Biological systems are resistant to perturbations caused by the environment and by the intrinsic noise of the system. Robustness to mutations is a particular aspect of robustness in which the phenotype is resistant to genotypic variation. Mutational robustness has been linked to the ability of the system to generate heritable genetic variation (a property known as evolvability). It is known that greater robustness leads to increased evolvability. Therefore, mechanisms that increase mutational robustness fuel evolvability. Two such mechanisms, molecular chaperones and gene duplication, have been credited with enormous importance in generating functional diversity through the increase of system's robustness to mutational insults. However, the way in which such mechanisms regulate robustness remains largely uncharacterized. In this review, I provide evidence in support of the role of molecular chaperones and gene duplication in innovation. Specifically, I present evidence that these mechanisms regulate robustness allowing unstable systems to survive long periods of time, and thus they provide opportunity for other mutations to compensate the destabilizing effects of functionally innovative mutations. The findings reported in this study set new questions with regards to the synergy between robustness mechanisms and how this synergy can alter the adaptive landscape of proteins. The ideas proposed in this article set the ground for future research in the understanding of the role of robustness in evolution. PMID:25447135

  18. Repair-misrepair model of cell survival

    International Nuclear Information System (INIS)

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

  19. High-density lipoprotein, mitochondrial dysfunction and cell survival mechanisms.

    Science.gov (United States)

    White, C Roger; Giordano, Samantha; Anantharamaiah, G M

    2016-09-01

    Ischemic injury is associated with acute myocardial infarction, percutaneous coronary intervention, coronary artery bypass grafting and open heart surgery. The timely re-establishment of blood flow is critical in order to minimize cardiac complications. Reperfusion after a prolonged ischemic period, however, can induce severe cardiomyocyte dysfunction with mitochondria serving as a major target of ischemia/reperfusion (I/R) injury. An increase in the formation of reactive oxygen species (ROS) induces damage to mitochondrial respiratory complexes leading to uncoupling of oxidative phosphorylation. Mitochondrial membrane perturbations also contribute to calcium overload, opening of the mitochondrial permeability transition pore (mPTP) and the release of apoptotic mediators into the cytoplasm. Clinical and experimental studies show that ischemic preconditioning (ICPRE) and postconditioning (ICPOST) attenuate mitochondrial injury and improve cardiac function in the context of I/R injury. This is achieved by the activation of two principal cell survival cascades: 1) the Reperfusion Injury Salvage Kinase (RISK) pathway; and 2) the Survivor Activating Factor Enhancement (SAFE) pathway. Recent data suggest that high density lipoprotein (HDL) mimics the effects of conditioning protocols and attenuates myocardial I/R injury via activation of the RISK and SAFE signaling cascades. In this review, we discuss the roles of apolipoproteinA-I (apoA-I), the major protein constituent of HDL, and sphingosine 1-phosphate (S1P), a lysosphingolipid associated with small, dense HDL particles as mediators of cardiomyocyte survival. Both apoA-I and S1P exert an infarct-sparing effect by preventing ROS-dependent injury and inhibiting the opening of the mPTP. PMID:27150975

  20. Influence of acute hypoxia and radiation quality on cell survival

    International Nuclear Information System (INIS)

    The purpose of this study was to measure the effect of acute oxygen depletion on cell survival for different types of radiation, experiments have been performed using Chinese hamster ovary (CHO) cells and R-3327-AT1 (RAT-1) rat prostate cancer cells. A special chamber has been developed to perform irradiations under different levels of oxygenation. The oxygen concentrations used were normoxia (air), hypoxia (94.5% N2, 5% CO2, 0.5% O2) and anoxia (95% N2, 5% CO2). Cells were exposed to X-rays and to C-, N- or O-ions with linear energy transfer (LET) values ranging from 100-160 keV/μm. The oxygen enhancement ratio (OER) and relative biological effectiveness (RBE) values have been calculated from the measured clonogenic survival curves. For both cell lines, the X-ray OER depended on the survival level. For particle irradiation, OER was not dependent on the survival level but decreased with increasing LET. The RBE of CHO cells under oxic conditions reached a plateau for LET values above 100 keV/μm, while it was still increasing under anoxia. In conclusion, the results demonstrated that our chamber could be used to measure radiosensitivity under intermediate hypoxia. Measurements suggest that ions heavier than carbon could be of additional advantage in the irradiation, especially of radioresistant hypoxic tumor regions. (author)

  1. 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. PMID:26113601

  2. Influence of chronic hypoxia and radiation quality on cell survival

    International Nuclear Information System (INIS)

    The purpose of this study was to investigate the influence of chronic hypoxia and anoxia on cell survival after low- and high-linear energy transfer (LET) radiation, Chinese hamster ovary K1 (CHO-K1) cells were kept for 24 h under chronic hypoxia (94.5% N2; 5% CO2; 0.5% O2) or chronic anoxia (95% N2; 5% CO2). Irradiation was performed using 250 kVp X-rays or carbon ions with a dose average LET of 100 keV/μm either directly under the chronic oxygenation states, or at different time points after reoxygenation. Moreover, the cell cycle distribution for cells irradiated under different chronic oxic states was measured over 24 h during reoxygenation. The measurements showed a fairly uniform cell cycle distribution under chronic hypoxia, similar to normoxic conditions. Chronic anoxia induced a block in G1 and a strong reduction of S-phase cells. A distribution similar to normoxic conditions was reached after 12 h of reoxygenation. CHO cells had a similar survival under both acute and chronic hypoxia. In contrast, survival after irradiation under chronic anoxia was slightly reduced compared to that under acute anoxia. We conclude that, in hamster cells, chronic anoxia is less effective than acute anoxia in inducing radioresistance for both X-rays and carbon ions, whereas in hypoxia, acute and chronic exposures have a similar impact on cell killing. (author)

  3. 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.

  4. Radiation effects on membranes - 1. Cellular permeability and cell survival

    International Nuclear Information System (INIS)

    The effect of various doses of γ radiation (5-60 krad) on the membrane permeability and cell survival of Candida albicans, a pathogenic yeast, was investigated. A reduction in the cell survival and in the accumulation of amino acids (proline, glycine, lysine, and glutamic acid) was observed following irradiation. The rate of oxygen uptake, which is often associated with transport, was also reduced. There was no damage to available sulfhydryl groups following the exposure of cells to various doses of γ radiation. The membrane lipid composition of C. albicans cells can be altered by growing them in alkanes of varying chain lengths. The effects of such altered lipid composition on radiosensitivity was examined. It was observed that C. albicans cells with altered lipid content acquire resistance to γ radiation

  5. PPAR-delta promotes survival of breast cancer cells in harsh metabolic conditions.

    Science.gov (United States)

    Wang, X; Wang, G; Shi, Y; Sun, L; Gorczynski, R; Li, Y-J; Xu, Z; Spaner, D E

    2016-01-01

    Expression of the nuclear receptor peroxisome proliferator activated receptor delta (PPARδ) in breast cancer cells is negatively associated with patient survival, but the underlying mechanisms are not clear. High PPARδ protein levels in rat breast adenocarcinomas were found to be associated with increased growth in soft agar and mice. Transgenic expression of PPARδ increased the ability of human breast cancer cell lines to migrate in vitro and form lung metastases in mice. PPARδ also conferred the ability to grow in exhausted tissue culture media and survive in low-glucose and other endoplasmic reticulum stress conditions such as hypoxia. Upregulation of PPARδ by glucocorticoids or synthetic agonists also protected human breast cancer cells from low glucose. Survival in low glucose was related to increased antioxidant defenses mediated in part by catalase and also to late AKT phosphorylation, which is associated with the prolonged glucose-deprivation response. Synthetic antagonists reversed the survival benefits conferred by PPARδ in vitro. These findings suggest that PPARδ conditions breast cancer cells to survive in harsh microenvironmental conditions by reducing oxidative stress and enhancing survival signaling responses. Drugs that target PPARδ may have a role in the treatment of breast cancer. PMID:27270614

  6. 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

  7. Gene Expression Profiling Predicts Survival in Conventional Renal Cell Carcinoma.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available BACKGROUND: Conventional renal cell carcinoma (cRCC accounts for most of the deaths due to kidney cancer. Tumor stage, grade, and patient performance status are used currently to predict survival after surgery. Our goal was to identify gene expression features, using comprehensive gene expression profiling, that correlate with survival. METHODS AND FINDINGS: Gene expression profiles were determined in 177 primary cRCCs using DNA microarrays. Unsupervised hierarchical clustering analysis segregated cRCC into five gene expression subgroups. Expression subgroup was correlated with survival in long-term follow-up and was independent of grade, stage, and performance status. The tumors were then divided evenly into training and test sets that were balanced for grade, stage, performance status, and length of follow-up. A semisupervised learning algorithm (supervised principal components analysis was applied to identify transcripts whose expression was associated with survival in the training set, and the performance of this gene expression-based survival predictor was assessed using the test set. With this method, we identified 259 genes that accurately predicted disease-specific survival among patients in the independent validation group (p < 0.001. In multivariate analysis, the gene expression predictor was a strong predictor of survival independent of tumor stage, grade, and performance status (p < 0.001. CONCLUSIONS: cRCC displays molecular heterogeneity and can be separated into gene expression subgroups that correlate with survival after surgery. We have identified a set of 259 genes that predict survival after surgery independent of clinical prognostic factors.

  8. The control of CD4+CD25+Foxp3+ regulatory T cell survival

    Directory of Open Access Journals (Sweden)

    Lenardo Michael J

    2008-02-01

    Full Text Available Abstract CD4+CD25+Foxp3+ regulatory T (Treg cells are believed to play an important role in suppressing autoimmunity and maintaining peripheral tolerance. How their survival is regulated in the periphery is less clear. Here we show that Treg cells express receptors for gamma chain cytokines and are dependent on an exogenous supply of these cytokines to overcome cytokine withdrawal apoptosis in vitro. This result was validated in vivo by the accumulation of Treg cells in Bim-/- and Bcl-2 tg mice which have arrested cytokine deprivation apoptosis. We also found that CD25 and Foxp3 expression were down-regulated in the absence of these cytokines. CD25+ cells from Scurfy mice do not depend on cytokines for survival demonstrating that Foxp3 increases their dependence on cytokines by suppressing cytokine production in Treg cells. Our study reveals that the survival of Treg cells is strictly dependent on cytokines and cytokine producing cells because they do not produce cytokines. Our study thus, demonstrates that different gamma chain cytokines regulate Treg homeostasis in the periphery by differentially regulating survival and proliferation. These findings may shed light on ways to manipulate Treg cells that could be utilized for their therapeutic applications. Reviewers This article was reviewed by: Avinash Bhandoola, Fred Ramsdell (nominated by Juan Carlos Zuniga-Pflucker and Anne Cooke.

  9. Effects of Triclosan on Neural Stem Cell Viability and Survival

    Science.gov (United States)

    Park, Bo Kyung; Gonzales, Edson Luck T.; Yang, Sung Min; Bang, Minji; Choi, Chang Soon; Shin, Chan Young

    2016-01-01

    Triclosan is an antimicrobial or sanitizing agent used in personal care and household products such as toothpaste, soaps, mouthwashes and kitchen utensils. There are increasing evidence of the potentially harmful effects of triclosan in many systemic and cellular processes of the body. In this study, we investigated the effects of triclosan in the survivability of cultured rat neural stem cells (NSCs). Cortical cells from embryonic day 14 rat embryos were isolated and cultured in vitro. After stabilizing the culture, triclosan was introduced to the cells with concentrations ranging from 1 μM to 50 μM and in varied time periods. Thereafter, cell viability parameters were measured using MTT assay and PI staining. TCS decreased the cell viability of treated NSC in a concentration-dependent manner along with increased expressions of apoptotic markers, cleaved caspase-3 and Bax, while reduced expression of Bcl2. To explore the mechanisms underlying the effects of TCS in NSC, we measured the activation of MAPKs and intracellular ROS. TCS at 50 μM induced the activations of both p38 and JNK, which may adversely affect cell survival. In contrast, the activities of ERK, Akt and PI3K, which are positively correlated with cell survival, were inhibited. Moreover, TCS at this concentration augmented the ROS generation in treated NSC and depleted the glutathione activity. Taken together, these results suggest that TCS can induce neurodegenerative effects in developing rat brains through mechanisms involving ROS activation and apoptosis initiation. PMID:26759708

  10. Recommended method for radioisotope red-cell survival studies

    International Nuclear Information System (INIS)

    As an amendment to a tentative ICSH Standard published in 1971, three 51Cr (sodium chromate) selected methods are briefly discussed as methods for red-cell survival studies. The acid citrate dextrose (ACD) method is accepted as the reference method and the technique described in detail. (U.K.)

  11. 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.

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

    International Nuclear Information System (INIS)

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

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

    OpenAIRE

    Gulbransen, Brian; Silver, Wayne; Finger, Tom

    2008-01-01

    Nasal solitary chemoreceptor cells (SCCs) are a population of specialized chemosensory epithelial cells presumed to broaden trigeminal chemoreceptivity in mammals (Finger et al., 2003). SCCs are innervated by peptidergic trigeminal nerve fibers (Finger et al., 2003) but it is currently unknown if intact innervation is necessary for SCC development or survival. We tested the dependence of SCCs on innervation by eliminating trigeminal nerve fibers during development with neurogenin-1 knockout m...

  14. Influence of acute hypoxia and radiation quality on cell survival

    OpenAIRE

    Tinganelli, Walter; Ma, Ning-Yi; von Neubeck, Cläre; Maier, Andreas; Schicker, Corinna; Kraft-Weyrather, Wilma; Durante, Marco

    2013-01-01

    To measure the effect of acute oxygen depletion on cell survival for different types of radiation, experiments have been performed using Chinese hamster ovary (CHO) cells and RAT-1 rat prostate cancer cells. A special chamber has been developed to perform irradiations under different levels of oxygenation. The oxygen concentrations used were normoxia (air), hypoxia (94.5% N2, 5% CO2, 0.5% O2) and anoxia (95% N2, 5% CO2). Cells were exposed to X-rays and to C-, N- or O-ions with linear energy ...

  15. Sox2 promotes survival of satellite glial cells in vitro

    International Nuclear Information System (INIS)

    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

  16. 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.

  17. Enhanced survival and decreased mutation frequency after photoreactivation of UV damage in rat kangaroo cells

    International Nuclear Information System (INIS)

    The effect of pyrimidine dimers on cytotoxicity, DNA repair and mutagenesis was studied in cells, derived from the rat kangaroo, which possess photoreactivating capabilities. A significant enhancement in colony-forming ability was achieved after UV irradiation in exponentially growing cells if photoreactivating light treatment followed the UV irradiation. If photoreactivation treatment was delayed 24h after UV irradiation, no significant increase in survival was observed. Assays of pyrimidine dimers, unscheduled DNA synthesis, and survival in contact-inhibited cells all confirmed a minor role of dark excision repair and a major role of photoreactivation. Photoreactivation decreased the frequency of mutations to 6-thioguanine resistance to a greater extent than the alteration seen in survival. Approximately 1.6 times the dose must be given to get equal killing in photoreactivated cells, whereas 4 times the dose must be given to obtain equal mutation frequencies in light-treated cells. This suggests that the removal of dimers is more effective in mutant reduction than enhancement of survival. (orig.)

  18. Enhanced survival and decreased mutation frequency after photoreactivation of UV damage in rat kangaroo cells

    Energy Technology Data Exchange (ETDEWEB)

    Wade, M.H.; Trosko, J.E. (Michigan State Univ., East Lansing (USA). Dept. of Pediatrics and Human Development)

    1983-08-01

    The effect of pyrimidine dimers on cytotoxicity, DNA repair and mutagenesis was studied in cells, derived from the rat kangaroo, which possess photoreactivating capabilities. A significant enhancement in colony-forming ability was achieved after UV irradiation in exponentially growing cells if photoreactivating light treatment followed the UV irradiation. If photoreactivation treatment was delayed 24h after UV irradiation, no significant increase in survival was observed. Assays of pyrimidine dimers, unscheduled DNA synthesis, and survival in contact-inhibited cells all confirmed a minor role of dark excision repair and a major role of photoreactivation. Photoreactivation decreased the frequency of mutations to 6-thioguanine resistance to a greater extent than the alteration seen in survival. Approximately 1.6 times the dose must be given to get equal killing in photoreactivated cells, whereas 4 times the dose must be given to obtain equal mutation frequencies in light-treated cells. This suggests that the removal of dimers is more effective in mutant reduction than enhancement of survival.

  19. Role of urease in megasome formation and Helicobacter pylori survival in macrophages.

    Science.gov (United States)

    Schwartz, Justin T; Allen, Lee-Ann H

    2006-06-01

    Previous studies have demonstrated that Helicobacter pylori (Hp) delays its entry into macrophages and persists inside megasomes, which are poorly acidified and accumulate early endosome autoantigen 1. Herein, we explored the role of Hp urease in bacterial survival in murine peritoneal macrophages and J774 cells. Plasmid-free mutagenesis was used to replace ureA and ureB with chloramphenicol acetyltransferase in Hp Strains 11637 and 11916. ureAB null Hp lacked detectable urease activity and did not express UreA or UreB as judged by immunoblotting. Deletion of ureAB had no effect on Hp binding to macrophages or the rate or extent of phagocytosis. However, intracellular survival of mutant organisms was impaired significantly. Immunofluorescence microscopy demonstrated that (in contrast to parental organisms) mutant Hp resided in single phagosomes, which were acidic and accumulated the lysosome marker lysosome-associated membrane protein-1 but not early endosome autoantigen 1. A similar phenotype was observed for spontaneous urease mutants derived from Hp Strain 60190. Treatment of macrophages with bafilomycin A1, NH4Cl, or chloroquine prevented acidification of phagosomes containing mutant Hp. However, only ammonium chloride enhanced bacterial viability significantly. Rescue of ureAB null organisms was also achieved by surface adsorption of active urease. Altogether, our data indicate a role for urease and urease-derived ammonia in megasome formation and Hp survival. PMID:16543403

  20. Roles of TRPM8 Ion Channels in Cancer: Proliferation, Survival, and Invasion

    Directory of Open Access Journals (Sweden)

    Nelson S. Yee

    2015-10-01

    Full Text Available The goal of this article is to provide a critical review of the transient receptor potential melastatin-subfamily member 8 (TRPM8 in cancers, with an emphasis on its roles in cellular proliferation, survival, and invasion. The TRPM8 ion channels regulate Ca²⁺ homeostasis and function as a cellular sensor and transducer of cold temperature. Accumulating evidence has demonstrated that TRPM8 is aberrantly expressed in a variety of malignant solid tumors. Clinicopathological analysis has shown that over-expression of TRPM8 correlates with tumor progression. Experimental data have revealed important roles of TRPM8 channels in cancer cells proliferation, survival, and invasion, which appear to be dependent on the cancer type. Recent reports have begun to reveal the signaling mechanisms that mediate the biological roles of TRPM8 in tumor growth and metastasis. Determining the mechanistic roles of TRPM8 in cancer is expected to elucidate the impact of thermal and chemical stimuli on the formation and progression of neoplasms. Translational research and clinical investigation of TRPM8 in malignant diseases will help exploit these ion channels as molecular biomarkers and therapeutic targets for developing precision cancer medicine.

  1. Surviving protein quality control catastrophes--from cells to organisms.

    Science.gov (United States)

    Schneider, Kim; Bertolotti, Anne

    2015-11-01

    Organisms have evolved mechanisms to cope with and adapt to unexpected challenges and harsh conditions. Unfolded or misfolded proteins represent a threat for cells and organisms, and the deposition of misfolded proteins is a defining feature of many age-related human diseases, including the increasingly prevalent neurodegenerative diseases. These protein misfolding diseases are devastating and currently cannot be cured, but are hopefully not incurable. In fact, the aggregation-prone and potentially harmful proteins at the origins of protein misfolding diseases are expressed throughout life, whereas the diseases are late onset. This reveals that cells and organisms are normally resilient to disease-causing proteins and survive the threat of misfolded proteins up to a point. This Commentary will outline the limits of the cellular resilience to protein misfolding, and discuss the possibility of pushing these limits to help cells and organisms to survive the threat of misfolding proteins and to avoid protein quality control catastrophes. PMID:26483388

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

    International Nuclear Information System (INIS)

    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

  3. 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.

  4. Endothelial cell-initiated signaling promotes the survival and self-renewal of cancer stem cells

    Science.gov (United States)

    Krishnamurthy, Sudha; Dong, Zhihong; Vodopyanov, Dmitry; Imai, Atsushi; Helman, Joseph I.; Prince, Mark E.; Wicha, Max S.; Nör, Jacques E.

    2010-01-01

    Recent studies have demonstrated that cancer stem cells play an important role in the pathobiology of head and neck squamous cell carcinomas (HNSCC). However, little is known about functional interactions between head and neck cancer stem-like cells (CSC) and surrounding stromal cells. Here, we used Aldehyde Dehydrogenase activity and CD44 expression to sort putative stem cells from primary human HNSCC. Implantation of 1,000 CSC (ALDH+CD44+Lin−) led to tumors in 13 (out of 15) mice, while 10,000 non-cancer stem cells (NCSC; ALDH−CD44−Lin−) resulted in 2 tumors in 15 mice. These data demonstrated that ALDH and CD44 select a sub-population of cells that are highly tumorigenic. The ability to self-renew was confirmed by the observation that ALDH+CD44+Lin− cells sorted from human HNSCC formed more spheroids (orospheres) in 3-D agarose matrices or ultra-low attachment plates than controls and were serially passaged in vivo. We observed that approximately 80% of the CSC were located in close proximity (within 100-µm radius) of blood vessels in human tumors, suggesting the existence of perivascular niches in HNSCC. In vitro studies demonstrated that endothelial cell-secreted factors promoted self-renewal of CSC, as demonstrated by the upregulation of Bmi-1 expression and the increase in the number of orospheres as compared to controls. Notably, selective ablation of tumor-associated endothelial cells stably transduced with a caspase-based artificial death switch (iCaspase-9) caused a marked reduction in the fraction of CSC in xenograft tumors. Collectively, these findings indicate that endothelial cell-initiated signaling can enhance the survival and self-renewal of head and neck cancer stem cells. PMID:21098716

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

    International Nuclear Information System (INIS)

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

  6. A phospholipase A₂ isolated from Lachesis muta snake venom increases the survival of retinal ganglion cells in vitro.

    Science.gov (United States)

    da Silva Cunha, Karinne Cristinne; Fuly, André Lopes; de Araujo, Elizabeth Giestal

    2011-03-15

    We have previously showed that a phospholipase A₂ isolated from Lachesis muta snake venom and named LM-PLA₂-I displayed particular biological activities, as hemolysis, inhibition on platelet aggregation, edema induction and myotoxicity. In the present work, we evaluated the effect of LM-PLA₂-I on the survival of axotomized rat retinal ganglion cells kept in vitro, as well as its mechanism of action. Our results clearly showed that treatment with LM-PLA₂-I increased the survival of ganglion cells (100% when compared to control cultures) and the treatment of LM-PLA₂-I with p-bromophenacyl bromide abolished this effect. This result indicates that the effect of LM-PLA₂-I on ganglion cell survival is entirely dependent on its enzymatic activity and the generation of lysophosphatidylcholine (LPC) may be a prerequisite to the observed survival. In fact, commercial LPC mimicked the effect of LM-PLA₂-I upon ganglion cell survival. To investigate the mechanism of action of LM-PLA₂-I, cultures were treated with chelerythrine chloride, BAPTA-AM, rottlerin and also with an inhibitor of c-junc kinase (JNKi). Our results showed that rottlerin and JNK inhibitor abolished the LM-PLA₂-I on ganglion cell survival. Taken together, our results showed that LM-PLA₂-I and its enzymatic product, LPC promoted survival of retinal ganglion cells through the protein kinase C pathway and strongly suggest a possible role of the PLA₂ enzyme and LPC in controlling the survival of axotomized neuronal cells. PMID:21223976

  7. Androgen receptor expression predicts breast cancer survival: the role of genetic and epigenetic events

    International Nuclear Information System (INIS)

    Breast cancer outcome, including response to therapy, risk of metastasis and survival, is difficult to predict using currently available methods, highlighting the urgent need for more informative biomarkers. Androgen receptor (AR) has been implicated in breast carcinogenesis however its potential to be an informative biomarker has yet to be fully explored. In this study, AR protein levels were determined in a cohort of 73 Grade III invasive breast ductal adenocarcinomas. The levels of Androgen receptor protein in a cohort of breast tumour samples was determined by immunohistochemistry and the results were compared with clinical characteristics, including survival. The role of defects in the regulation of Androgen receptor gene expression were examined by mutation and methylation screening of the 5' end of the gene, reporter assays of the 5' and 3' end of the AR gene, and searching for miRNAs that may regulate AR gene expression. AR was expressed in 56% of tumours and expression was significantly inversely associated with 10-year survival (P = 0.004). An investigation into the mechanisms responsible for the loss of AR expression revealed that hypermethylation of the AR promoter is associated with loss of AR expression in breast cancer cells but not in primary breast tumours. In AR negative breast tumours, mutation screening identified the same mutation (T105A) in the 5'UTR of two AR negative breast cancer patients but not reported in the normal human population. Reporter assay analysis of this mutation however found no evidence for a negative impact on AR 5'UTR activity. The role of miR-124 in regulating AR expression was also investigated, however no evidence for this was found. This study highlights the potential for AR expression to be an informative biomarker for breast cancer survival and sets the scene for a more comprehensive investigation of the molecular basis of this phenomenon

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

    Directory of Open Access Journals (Sweden)

    Lisa Mutschelknaus

    Full Text Available 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

  9. The role of metallothionein II in neuronal differentiation and survival

    DEFF Research Database (Denmark)

    Køhler, Lene B; Berezin, Vladimir; Bock, Elisabeth;

    2003-01-01

    -I+II can affect neurons directly. It is likely that MT isoforms could be beneficial also during neurodegenerative disorders. In this study, we have examined if MT-II affects survival and neurite extension of dopaminergic and hippocampal neurons. We show for the first time that MT-II treatment can...... significantly stimulate neurite extension from both dopaminergic and hippocampal neurons. Moreover, MT-II treatment significantly increases survival of dopaminergic neurons exposed to 6-hydroxydopamine (6-OHDA) and protects significantly hippocampal neurons from amyloid beta-peptide-induced neurotoxicity...

  10. A role for insect galectins in parasite survival.

    Science.gov (United States)

    Kamhawi, Shaden; Ramalho-Ortigao, Marcelo; Pham, Van M; Kumar, Sanjeev; Lawyer, Phillip G; Turco, Salvatore J; Barillas-Mury, Carolina; Sacks, David L; Valenzuela, Jesus G

    2004-10-29

    Insect galectins are associated with embryonic development or immunity against pathogens. Here, we show that they can be exploited by parasites for survival in their insect hosts. PpGalec, a tandem repeat galectin expressed in the midgut of the sandfly Phlebotomus papatasi, is used by Leishmania major as a receptor for mediating specific binding to the insect midgut, an event crucial for parasite survival, and accounts for species-specific vector competence for the most widely distributed form of cutaneous leishmaniasis in the Old World. In addition, these studies demonstrate the feasibility of using midgut receptors for parasite ligands as target antigens for transmission-blocking vaccines. PMID:15543683

  11. Novel genes underlying beta cell survival in metabolic stress

    OpenAIRE

    Singh, Himadri; Farouk, Mohammed; Bose, Barish Baran; Singh, Prabhakar

    2013-01-01

    Relative insulin deficiency, in response to increased metabolic demand (obesity, genetic insulin resistance, pregnancy and aging) lead to Type2 diabetes. Susceptibility of the type 2 diabetes has a genetic basis, as a subset of people with risk factors (obesity, Insulin Resistance, pregnancy), develop Type2 Diabetes. We aimed to identify ‘cluster’ of overexpressed genes, underlying increased beta cell survival in diabetes resistant C57BL/6J ob/ob mice (compared to diabetes susceptible BTBR ob...

  12. 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.

  13. EGFR overexpressing cells and tumors are dependent on autophagy for growth and survival

    International Nuclear Information System (INIS)

    Background and purpose: The epidermal growth factor receptor (EGFR) is overexpressed, amplified or mutated in various human epithelial tumors, and is associated with tumor aggressiveness and therapy resistance. Autophagy activation provides a survival advantage for cells in the tumor microenvironment. In the current study, we assessed the potential of autophagy inhibition (using chloroquine (CQ)) in treatment of EGFR expressing tumors. Material and methods: Quantitative PCR, immunohistochemistry, clonogenic survival, proliferation assays and in vivo tumor growth were used to assess this potential. Results: We show that EGFR overexpressing xenografts are sensitive to CQ treatment and are sensitized to irradiation by autophagy inhibition. In HNSSC xenografts, a correlation between EGFR and expression of the autophagy marker LC3b is observed, suggesting a role for autophagy in EGFR expressing tumors. This observation was substantiated in cell lines, showing high EGFR expressing cells to be more sensitive to CQ addition as reflected by decreased proliferation and survival. Surprisingly high EGFR expressing cells display a lower autophagic flux. Conclusions: The EGFR high expressing cells and tumors investigated in this study are highly dependent on autophagy for growth and survival. Inhibition of autophagy may therefore provide a novel treatment opportunity for EGFR overexpressing tumors

  14. Nuclear trafficking of EGFR by Vps34 represses Arf expression to promote lung tumor cell survival.

    Science.gov (United States)

    Dayde, D; Guerard, M; Perron, P; Hatat, A-S; Barrial, C; Eymin, B; Gazzeri, S

    2016-07-28

    Epidermal growth factor receptor (EGFR) is a cell surface receptor that has an essential role in cell proliferation and survival, and overexpression of EGFR is a common feature of human cancers. In Non-small-cell lung cancer (NSCLC), activating mutations of EGFR have also been described. We recently showed that mutant EGFR-L858R inhibits the expression of the p14ARF tumor-suppressor protein to promote cell survival. In this study, we defined the molecular bases by which EGFR controls Arf expression. Using various lung tumor models, we showed that EGF stimulation inhibits Arf transcription by a mechanism involving the nuclear transport and recruitment of EGFR to the Arf promoter. We unraveled the vesicular trafficking protein Vps34 as a mediator of EGFR nuclear trafficking and showed that its neutralization prevents the accumulation of EGFR to the Arf promoter in response to ligand activation. Finally, in lung tumor cells that carry mutant EGFR-L858R, we demonstrated that inhibition of Vps34 using small interfering RNA restrains nuclear EGFR location and restores Arf expression leading to apoptosis. These findings identify the Arf tumor suppressor as a new transcriptional target of nuclear EGFR and highlight Vps34 as an important regulator of the nuclear EGFR/Arf survival pathway. As a whole, they provide a mechanistic explanation to the inverse correlation between nuclear expression of EGFR and overall survival in NSCLC patients. PMID:26686095

  15. Microvesicles derived from mesenchymal stem cells enhance survival in a lethal model of acute kidney injury.

    Directory of Open Access Journals (Sweden)

    Stefania Bruno

    Full Text Available Several studies demonstrated that treatment with mesenchymal stem cells (MSCs reduces cisplatin mortality in mice. Microvesicles (MVs released from MSCs were previously shown to favor renal repair in non lethal toxic and ischemic acute renal injury (AKI. In the present study we investigated the effects of MSC-derived MVs in SCID mice survival in lethal cisplatin-induced AKI. Moreover, we evaluated in vitro the effect of MVs on cisplatin-induced apoptosis of human renal tubular epithelial cells and the molecular mechanisms involved. Two different regimens of MV injection were used. The single administration of MVs ameliorated renal function and morphology, and improved survival but did not prevent chronic tubular injury and persistent increase in BUN and creatinine. Multiple injections of MVs further decreased mortality and at day 21 surviving mice showed normal histology and renal function. The mechanism of protection was mainly ascribed to an anti-apoptotic effect of MVs. In vitro studies demonstrated that MVs up-regulated in cisplatin-treated human tubular epithelial cells anti-apoptotic genes, such as Bcl-xL, Bcl2 and BIRC8 and down-regulated genes that have a central role in the execution-phase of cell apoptosis such as Casp1, Casp8 and LTA. In conclusion, MVs released from MSCs were found to exert a pro-survival effect on renal cells in vitro and in vivo, suggesting that MVs may contribute to renal protection conferred by MSCs.

  16. Dynamic observation of micronuclei and cell survival in human liver cancer cells irradiated by heavy ion

    International Nuclear Information System (INIS)

    The author reported dynamic changes of micronuclei and cell survival in human liver cancer cells SMMC-7721 irradiated by 25 MeV/u 40Ar14+. The results show: (1) Change rules of frequency of micronuclei induced by single irradiation and fractionation irradiation with culture time have not clear difference. (2) Irradiated (single, fractionation) liver cancer cells grow much slower than control and their survival number with culture time shows decay tendency. (3) Dynamic changes of the relationship between micronucleus frequency and cell survival number presents negative correlation. (4) For cells irradiated by dose of 0.68 Gy, 6.8 Gy and 68 Gy, frequency of micronuclei following culture 24 hours is lower than that following culture 96 hours. (5) Negative dependences of survival number of liver cancer cells for culture 24 hours and 48 hours on dose are demonstrated

  17. SYK allelic loss and the role of Syk-regulated genes in breast cancer survival.

    Directory of Open Access Journals (Sweden)

    Jan Blancato

    Full Text Available Heterozygotic loss of SYK, a non-receptor tyrosine kinase, gives rise to mouse mammary tumor formation where Syk protein levels are reduced by about half; loss of SYK mRNA is correlated with invasive cell behavior in in vitro models; and SYK loss has been correlated with distant metastases in patients. Here, allelic loss of the SYK gene was explored in breast ductal carcinoma in situ (DCIS using fluorescence in situ hybridization and pyrosequencing, respectively, and in infiltrating ductal carcinoma (IDC using genomic data from The Cancer Genome Atlas (TCGA. Allelic loss was present in a subset of DCIS cases where adjacent IDC was present. SYK copy number loss was found in about 26% of 1002 total breast cancer cases and 30% of IDC cases. Quantitative immunofluorescence revealed Syk protein to be six-fold higher in infiltrating immune cells compared with epithelial cells. This difference distorted tumor cell mRNA and protein levels in extracts. 20% of 1002 IDC cases contained elevated immune cell infiltration as estimated by elevated immune-specific mRNAs. In cases without immune cell infiltration, loss of SYK copy number was associated with a significant reduction of SYK mRNA. Here we define a 55 Gene Set consisting of Syk interacting, motility- and invasion-related genes. We found that overall survival was significantly reduced in IDC and Luminal A+B cases where copy number and mutations of these 55 genes were affected (Kaplan-Meier, Logrank test p-value 0.007141 and Logrank test p-value 0.001198, respectively. We conclude that reduction in Syk expression and contributions of genomic instability to copy number and mutations in the 55 Syk interacting genes significantly contribute to poorer overall patient survival. A closer examination of the role of Syk interacting motility and invasion genes and their prognostic and/or causative association with metastatic disease and patient outcome is warranted.

  18. Ceruloplasmin reduces DNA double strand breaks and improves cell survival in lymphoblastoid cells

    International Nuclear Information System (INIS)

    Full text: Ionizing radiation through oxidative free radical production causes dose-dependent oxidative damage to biological macromolecules. To reduce the oxidative stress from ionizing radiation, use of antioxidants has been suggested as a prophylactic and early remedy of pathogenic therapy. Ceruloplasmin (Cp), a plasma protein produced by the liver, belongs to a class of multi copper ferroxidases known for their role in iron metabolism in vertebrates, including humans. Functions of Cp include copper transport, ferroxidase and aminooxidase activities. Serum Cp concentration fluctuates during inflammation, infection, trauma and irradiation. The role of Cp as an antioxidant after irradiation is not fully understood. Our aim was to investigate the radioprotective efficacy of Cp. We studied the effect of ceruloplasmin on the in-vitro radiosensitivity of lymphoblastoid cells lines after gamma-ray irradiation. We used radiosensitive cell lines LB0003, LB0004 and LB 0005, established from individuals who developed late radiation necrosis following curative radiotherapy and non-sensitive cell lines Masci and LB0001 as controls. The cell lines were irradiated with doses from 0 - 60 Gy. Genomic DNA was extracted at 0 - 24h after irradiation and subjected to PFGE to analyse the initial quantity of DNA DSBs and the quantity of unrepaired DSBs to evaluate the kinetics of DSB rejoining. Human Cp (0.05 or 0.5mg/ml) was added to cell cultures 30 min before or 5 min after irradiation. In the presence of Cp cell survival was increased and the level of DBSs reduced demonstrating its radioprotective effect and the potential mechanism of its protection against radiation effects. Its radioprotective efficacy on dose and time of administration of Cp. The radiosensitive cell lines differ from controls by kinetics of DSBs repair. Importantly, in presence of ceruloplasmin the level of DNA DSB was reduced and the kinetics of DNA DSB repair became comparable to that in controls

  19. Dendritic cell maturation and survival are differentially regulated by TNF receptors 1 and 21

    Science.gov (United States)

    Maney, Nicola J.; Reynolds, Gary

    2016-01-01

    The capacity of dendritic cells (DC) to regulate adaptive immunity is controlled by their maturation state and lifespan. Although TNF is a well-known maturation and survival factor for DC, the role of the two TNF receptors (TNFR), TNFR1 and TNFR2, in mediating these effects is poorly understood. By using unique TNF variants that selectively signal through TNFR1 and/or TNFR2, we demonstrate differential functions of TNFR in human monocyte-derived and blood CD1c+ DC. Activation of TNFR1, but not TNFR2, efficiently induced DC maturation, as defined by enhanced expression of cell surface maturation markers (CD83, CD86 and HLA-DR) as well as enhanced T-cell stimulatory capacity. In contrast, both TNFR1 and TNFR2 significantly protected DC against cell death indicating that innate signals can promote DC survival in the absence of DC maturation. We further show differential activation of NFκB signaling pathways by the TNFR: TNFR1 activated both the p65 and p52 pathways, whereas TNFR2 triggered p52, but not p65 activation. Accordingly, the p65 NFκB pathway only played a role in the pro-survival effect of TNFR1. However, cell death protection through both TNFR was mediated through the Bcl-2/Bcl-xL pathway. Together, our data show that TNFR1-, but not TNFR2-signaling induces DC maturation, whereas DC survival can be mediated independently through both TNFR. These data indicate differential but partly overlapping responses through TNFR1 and TNFR2 in both inflammatory and conventional DC, and demonstrate that DC maturation and DC survival can be regulated through independent signaling pathways. PMID:25288570

  20. 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.

  1. Cell survival and iso-effect contours in irradiated tissues

    International Nuclear Information System (INIS)

    Cell population kinetic parameters derived from radiobiological experiments and analysis of clinical data can be used to compute cellular surviving fractions in irradiated tumours and normal tissues. A three-component model of cellular radiation lethality, capable of simulating irreparable lethal events, reversible or sublethal effects and tissue repopulation processes, has proved adequate for clinical purposes. On this basis, computer programs have been developed for generating iso-effect (iso-survival) functions for various fractionation intervals in several tissues and tumours; for determining surviving fractions, equivalent single doses, and probabilities of response with specified fractionation schemes; and for optimizing treatment by identifying the procedure giving the highest probability of uncomplicated cure for a given tumour type growing in a specified location. If the relevant parameters for each of the tissues traversed by the beam, the physical dose absorbed at each point of interest, and the size, number and sequence of fractional doses reaching that point are known, then a series of computations of cellular surviving fractions can be made and used to draw iso-effect contours as a supplement to the physical isodose distribution in the same region. Procedures for both physical and biological optimization of the whole treatment plan are suggested. (author)

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

    International Nuclear Information System (INIS)

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

  3. 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.

  4. Prolonged survival after experimental paraquat intoxication: role of alternative antioxidants.

    Science.gov (United States)

    Lugo-Vallín, Nelly del Valle; Pascuzzo-Lima, Carmine; Maradei-Irastorza, Idania; Ramírez-Sánchez, Manuel; Sosa-Sequera, Miriam; Aguero-Penã, Rafael; Granado-Duque, Angel

    2002-02-01

    Since paraquat poisoning causes multiorgan damage through the generation of several redox products, the usual therapy includes antioxidative drugs, such as N-acetylcysteine. We investigated whether selected antioxidative drugs can improve survival from acute paraquat toxicity. Forty-eight male 2-3-mo-old Wistar rats were divided into 4 groups receiving paraquat dichloride in a single injection (11 mg/kg bw ip) I h before the administration of normal saline (control ip), S-carboxymethylcysteine (600 mg/kg bw po), propofol (100 mg/kg bw ip) or trimetazidine (10 mg/kg bw po). Animals were observed for 7 d. The median survival time in the control group was 3 d whereas it was 4 (p = 0.15), 4.5 (p trimetazidine, S-carboxymethylcysteine or propofol-treated groups, respectively. PMID:11824777

  5. Improving Oral Cancer Survival: The Role of Dental Providers

    OpenAIRE

    MESSADI, DIANA V.; Wilder-Smith, Petra; WOLINSKY, LAWRENCE

    2009-01-01

    Oral cancer accounts for 2 percent to 4 percent of all cancers diagnosed each year in the United States. In contrast to other cancers, the overall U.S. survival rate from oral cancer has not improved during the past 50 years, mostly due to late-stage diagnosis. Several noninvasive oral cancer detection techniques that emerged in the past decade will be discussed, with a brief overview of most common oral cancer chemopreventive agents.

  6. The role of events in the survival of rural retail

    OpenAIRE

    Engström, Christina; Håkansson, Johan

    2012-01-01

    Rural retailers in Sweden are currently in need of new strategies in order to meet the increasing competition from urban shopping centers and increased customer mobility. This study examines the how events can influence local retail survival in rural areas. In interviews, local stakeholders involved in retail, events and municipal decision-making describes how events affect the retail of a rural municipality in Sweden. A questionnaire survey among the visitors of two local events is also cond...

  7. Red cell survival and sequestration in acute intermittent porphyria

    International Nuclear Information System (INIS)

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

  8. A mathematical model describing survival of mammalian cells after irradiation

    International Nuclear Information System (INIS)

    The author presents a model for describing the dose/effect curve which also considers recent findings about molecular damage to DNA and its enzymatic repair by the cell. To understand this model better, the author describes a number of important molecular details of the effect of radiation. The SSR model (Survival with Saturable Repair) describes correctly most of the experimental results. The concept of 'saturable repair' is based on the basic assumption of enzymatic repair kinetics for DNA damage based on the Michaelis-Menten enzyme kinetics. The existence of potentially lethally damaged cells is postulated which may be turned into fully viable cells by successful DNA repair. In case of repair failure, the damaged cells will die. The model also includes the immediate production of lethal damage. (orig./MG)

  9. PERK Integrates Oncogenic Signaling and Cell Survival During Cancer Development.

    Science.gov (United States)

    Bu, Yiwen; Diehl, J Alan

    2016-10-01

    Unfolded protein responses (UPR), consisting of three major transducers PERK, IRE1, and ATF6, occur in the midst of a variety of intracellular and extracellular challenges that perturb protein folding in the endoplasmic reticulum (ER). ER stress occurs and is thought to be a contributing factor to a number of human diseases, including cancer, neurodegenerative disorders, and various metabolic syndromes. In the context of neoplastic growth, oncogenic stress resulting from dysregulation of oncogenes such as c-Myc, Braf(V600E) , and HRAS(G12V) trigger the UPR as an adaptive strategy for cancer cell survival. PERK is an ER resident type I protein kinase harboring both pro-apoptotic and pro-survival capabilities. PERK, as a coordinator through its downstream substrates, reprograms cancer gene expression to facilitate survival in response to oncogenes and microenvironmental challenges, such as hypoxia, angiogenesis, and metastasis. Herein, we discuss how PERK kinase engages in tumor initiation, transformation, adaption microenvironmental stress, chemoresistance and potential opportunities, and potential opportunities for PERK targeted therapy. J. Cell. Physiol. 231: 2088-2096, 2016. © 2016 Wiley Periodicals, Inc. PMID:26864318

  10. 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

    2016-01-01

    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. PMID:27187358

  11. 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.

  12. CXCR4 engagement promotes dendritic cell survival and maturation

    International Nuclear Information System (INIS)

    It has been reported that human monocyte derived-dendritic cells (DCs) express CXCR4, responsible for chemotaxis to CXCL12. However, it remains unknown whether CXCR4 is involved in other functions of DCs. Initially, we found that CXCR4 was expressed on bone marrow-derived DCs (BMDCs). The addition of specific CXCR4 antagonist, 4-F-Benzoyl-TN14003, to the culture of mouse BMDCs decreased their number, especially the mature subset of them. The similar effect was found on the number of Langerhans cells (LCs) but not keratinocytes among epidermal cell suspensions. Since LCs are incapable of proliferating in vitro, these results indicate that CXCR4 engagement is important for not only maturation but also survival of DCs. Consistently, the dinitrobenzene sulfonic acid-induced, antigen-specific in vitro proliferation of previously sensitized lymph node cells was enhanced by CXCL12, and suppressed by CXCR4 antagonist. These findings suggest that CXCL12-CXCR4 engagement enhances DC maturation and survival to initiate acquired immune response

  13. 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. PMID:26491231

  14. Cooperation of B cells and T cells is required for survival of mice infected with vesicular stomatitis virus

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Nansen, A; Andersen, C; Johansen, J; Marker, O; Christensen, Jan Pravsgaard

    1997-01-01

    some antiviral activity, but CD4+ T cells sufficed for survival and were required for optimal resistance. Consistent with this it was found that in nude mice a lethal outcome could be prevented by transfer of CD8-depleted cells from B cell-deficient mice. Thus our results clearly demonstrate that while......To define the role of T cells and B cells in resistance to vesicular stomatitis virus (VSV) infection, knockout mice with different specific immune defects on an identical background were infected i.v. and the outcome of infection was compared; in this way a more complete picture of the relative...... importance of various host defence mechanisms could be obtained. Compared to T and B cell-deficient SCID mice which all succumbed from encephalitis within 5-9 days of infection, T cell-deficient nude mice generally lived longer, but within a period of approximately 1 month after challenge all died. In...

  15. Single-cell hydrogel encapsulation for enhanced survival of human marrow stromal cells.

    Science.gov (United States)

    Karoubi, Golnaz; Ormiston, Mark L; Stewart, Duncan J; Courtman, David W

    2009-10-01

    Inadequate extracellular matrix cues and subsequent apoptotic cell death are among crucial factors currently limiting cell viability and organ retention in cell-based therapeutic strategies for vascular regeneration. Here we describe the use of a single-cell hydrogel capsule to provide enhanced cell survival of adherent cells in transient suspension culture. Human marrow stromal cells (hMSCs) were singularly encapsulated in agarose capsules containing the immobilized matrix molecules, fibronectin and fibrinogen to ameliorate cell-matrix survival signals. MSCs in the enriched capsules demonstrated increased viability, greater metabolic activity and enhanced cell-cytoskeletal patterning. Increased cell viability resulted from the re-induction of cell-matrix interactions likely via integrin clustering and subsequent activation of the extracellular signal regulated MAPK (ERK)/mitogen activated protein kinase (MAPK) signaling cascade. Proof of principle in-vivo studies, investigating autologous MSC delivery into Fisher 344 rat hindlimb, depicted a significant increase in the number of engrafted cells using the single-cell encapsulation system. Incorporation of immobilized adhesion molecules compensates, at least in part, for the missing cell-matrix cues, thereby attenuating the initial anoikis stimuli and providing protection from subsequent apoptosis. Thus, this single-cell encapsulation strategy may markedly enhance therapeutic cell survival in targeted tissues. PMID:19595454

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

    Directory of Open Access Journals (Sweden)

    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. 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.

  18. The B-cell receptor orchestrates environment-mediated lymphoma survival and drug resistance in B-cell malignancies.

    Science.gov (United States)

    Shain, K H; Tao, J

    2014-08-01

    Specific niches within the lymphoma tumor microenvironment (TME) provide sanctuary for subpopulations of tumor cells through stromal cell-tumor cell interactions. These interactions notably dictate growth, response to therapy and resistance of residual malignant B cells to therapeutic agents. This minimal residual disease (MRD) remains a major challenge in the treatment of B-cell malignancies and contributes to subsequent disease relapse. B-cell receptor (BCR) signaling has emerged as essential mediator of B-cell homing, survival and environment-mediated drug resistance (EMDR). Central to EMDR are chemokine- and integrin-mediated interactions between lymphoma and the TME. Further, stromal cell-B cell adhesion confers a sustained BCR signaling leading to chemokine and integrin activation. Recently, the inhibitors of BCR signaling have garnered a substantial clinical interest because of their effectiveness in B-cell disorders. The efficacy of these agents is, at least in part, attributed to attenuation of BCR-dependent lymphoma-TME interactions. In this review, we discuss the pivotal role of BCR signaling in the integration of intrinsic and extrinsic determinants of TME-mediated lymphoma survival and drug resistance. PMID:24037527

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

    Directory of Open Access Journals (Sweden)

    Hourinaz Behesti

    2013-01-01

    BMI1 is a potent inducer of neural stem cell self-renewal and neural progenitor cell proliferation during development and in adult tissue homeostasis. It is overexpressed in numerous human cancers – including medulloblastomas, in which its functional role is unclear. We generated transgenic mouse lines with targeted overexpression of Bmi1 in the cerebellar granule cell lineage, a cell type that has been shown to act as a cell of origin for medulloblastomas. Overexpression of Bmi1 in granule cell progenitors (GCPs led to a decrease in cerebellar size due to decreased GCP proliferation and repression of the expression of cyclin genes, whereas Bmi1 overexpression in postmitotic granule cells improved cell survival in response to stress by altering the expression of genes in the mitochondrial cell death pathway and of Myc and Lef-1. Although no medulloblastomas developed in ageing cohorts of transgenic mice, crosses with Trp53−/− mice resulted in a low incidence of medulloblastoma formation. Furthermore, analysis of a large collection of primary human medulloblastomas revealed that tumours with a BMI1high TP53low molecular profile are significantly enriched in Group 4 human medulloblastomas. Our data suggest that different levels and timing of Bmi1 overexpression yield distinct cellular outcomes within the same cellular lineage. Importantly, Bmi1 overexpression at the GCP stage does not induce tumour formation, suggesting that BMI1 overexpression in GCP-derived human medulloblastomas probably occurs during later stages of oncogenesis and might serve to enhance tumour cell survival.

  20. Heat shock proteins in the retina: Focus on HSP70 and alpha crystallins in ganglion cell survival.

    Science.gov (United States)

    Piri, Natik; Kwong, Jacky M K; Gu, Lei; Caprioli, Joseph

    2016-05-01

    Heat shock proteins (HSPs) belong to a superfamily of stress proteins that are critical constituents of a complex defense mechanism that enhances cell survival under adverse environmental conditions. Cell protective roles of HSPs are related to their chaperone functions, antiapoptotic and antinecrotic effects. HSPs' anti-apoptotic and cytoprotective characteristics, their ability to protect cells from a variety of stressful stimuli, and the possibility of their pharmacological induction in cells under pathological stress make these proteins an attractive therapeutic target for various neurodegenerative diseases; these include Alzheimer's, Parkinson's, Huntington's, prion disease, and others. This review discusses the possible roles of HSPs, particularly HSP70 and small HSPs (alpha A and alpha B crystallins) in enhancing the survival of retinal ganglion cells (RGCs) in optic neuropathies such as glaucoma, which is characterized by progressive loss of vision caused by degeneration of RGCs and their axons in the optic nerve. Studies in animal models of RGC degeneration induced by ocular hypertension, optic nerve crush and axotomy show that upregulation of HSP70 expression by hyperthermia, zinc, geranyl-geranyl acetone, 17-AAG (a HSP90 inhibitor), or through transfection of retinal cells with AAV2-HSP70 effectively supports the survival of injured RGCs. RGCs survival was also stimulated by overexpression of alpha A and alpha B crystallins. These findings provide support for translating the HSP70- and alpha crystallin-based cell survival strategy into therapy to protect and rescue injured RGCs from degeneration associated with glaucomatous and other optic neuropathies. PMID:27017896

  1. Mitochondrial Variations in Non-Small Cell Lung Cancer (NSCLC) Survival

    OpenAIRE

    Zhaoxi Wang; Sojung Choi; Jinseon Lee; Yen-Tsung Huang; Feng Chen; Yang Zhao; Xihong Lin; Donna Neuberg; Jhingook Kim; Christiani, David C.

    2015-01-01

    Mutations in the mtDNA genome have long been suspected to play an important role in cancer. Although most cancer cells harbor mtDNA mutations, the question of whether such mutations are associated with clinical prognosis of lung cancer remains unclear. We resequenced the entire mitochondrial genomes of tumor tissue from a population of 250 Korean patients with non-small cell lung cancer (NSCLC). Our analysis revealed that the haplogroup (D/D4) was associated with worse overall survival (OS) o...

  2. Cancer stem cells and chemoresistance: The smartest survives the raid.

    Science.gov (United States)

    Zhao, Jihe

    2016-04-01

    Chemoresistant metastatic relapse of minimal residual disease plays a significant role for poor prognosis of cancer. Growing evidence supports a critical role of cancer stem cell (CSC) behind the mechanisms for this deadly disease. This review briefly introduces the basics of the conventional chemotherapies, updates the CSC theories, highlights the molecular and cellular mechanisms by which CSC smartly designs and utilizes multiple lines of self-defense to avoid being killed by chemotherapy, and concisely summarizes recent progress in studies on CSC-targeted therapies in the end, with the hope to help guide future research toward developing more effective therapeutic strategies to eradicate tumor cells in the patients. PMID:26899500

  3. Tumour-stromal interactions: Integrins and cell adhesions as modulators of mammary cell survival and transformation

    International Nuclear Information System (INIS)

    Stromal–epithelial interactions modulate mammary epithelial cell (MEC) growth and apoptosis by influencing cell adhesion and tissue organization. Perturbations in the mammary stroma and cell adhesion characterize breast tumors and underlie the altered tissue organization, disrupted tissue homeostasis and enhanced survival phenotype of the disease. Apoptosis resistance likely arises during malignant transformation via genetic and epigenetic modification of cell adhesion pathways induced by a changing tissue microenvironment. Acquisition of adhesion-linked survival networks that enhance MEC viability in the absence of basement membrane interactions probably promote malignant transformation, and may render breast tumors sufficiently resistant to exogenous apoptotic stimuli to generate multidrug resistance

  4. Roles of imprinted genes in neural stem cells.

    Science.gov (United States)

    Hoffmann, Anke; Daniel, Guillaume; Schmidt-Edelkraut, Udo; Spengler, Dietmar

    2014-01-01

    Imprinted genes and neural stem cells (NSC) play an important role in the developing and mature brain. A central theme of imprinted gene function in NSCs is cell survival and G1 arrest to control cell division, cell-cycle exit, migration and differentiation. Moreover, genomic imprinting can be epigenetically switched off at some genes to ensure stem cell quiescence and differentiation. At the genome scale, imprinted genes are organized in dynamic networks formed by interchromosomal interactions and transcriptional coregulation of imprinted and nonimprinted genes. Such multilayered networks may synchronize NSC activity with the demand from the niche resembling their roles in adjusting fetal size. PMID:25431944

  5. Evaluation of motion tracking by cell survival measurements

    International Nuclear Information System (INIS)

    At GSI patients with stationary tumors are treated with a rasterscanned carbon ion beam. For moving targets interplay possibly deteriorates the dose distribution because target motion and scanner motion interfere. Several motion mitigation techniques are proposed to solve this problem. We use a fully integrated 3D online motion compensation system to track target motion of phantoms which includes adaptation of the Bragg peak position. To validate motion tracking with biological systems we conducted a series of repetitive experiments with hamster cells grown in wellplates. The wellplates were placed on a sliding table to induce lateral as well as longitudinal motion. Irradiations were performed with stationary wellplates and by tracking moving wellplates. Multiple samples were irradiated to gain statistics. As a result, we observed no significant difference in cell survival between the motion compensated measurements in comparison to a stationary reference irradiation. We conclude that our motion compensation system allows correct delivery of the biologically effective dose to moving phantoms

  6. Clinical characteristics and survival of children with Langerhans cell hystiocytosis

    Directory of Open Access Journals (Sweden)

    Krstovski Nada

    2008-01-01

    Full Text Available INTRODUCTION Langerhans cell histiocytosis is a rare disease in children, initial presentation is variable, clinical course, prognosis and survival are mostly unpredictable. OBJECTIVE To summarise clinical characteristics and treatment results in children with Langerhans cell histiocytosis. METHOD Retrospectively there were analyzed patients with LCH diagnosed and treated at Hematology Department of University Children's Hospital in Belgrade from 1990 to 2006. Clinical presentation, therapy and survival according to Kaplan-Meier's statistical test was analysed. RESULTS 30 patients were treated, aged from 4 months to 14 years, mean 3.9 years, median 2.3 years, 18 (60% males, 12 (40% females. A single system disease was diagnosed in 16 (53% patients, of whom 6 patients with multifocal bone disease. All patients were in complete remission averagely following162 and 82 months respectively. Multisystem disease was found in 14 (47% patients. The lymph nodes and skin were more frequently involved organs than the central nervous system (diabetes insipidus, lung, liver and spleen. The number of involved organs ranged from 2 to 8, mean 4.2. Four patients died due to disease progression 3, 16, 36 and 66 months after diagnosis. Nine patents with multisystem disease were in remission with 117 months of follow-up. One patient was lost on follow-up. CONCLUSION The clinical course of patients with a single system disease is usually benign while a multisystem disease has to be aggressively treated with precise initial evaluation and staging before therapy.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Lck is involved in interleukin-2 induced proliferation but not cell survival in human T cells through a MAP kinase-independent pathway

    DEFF Research Database (Denmark)

    Brockdorff, J; Nielsen, M; Kaltoft, K;

    2000-01-01

    The role of Lck in IL-2-induced proliferation and cell survival is still controversial. Here, we show that the Src family kinase inhibitor, PP1, reduced the IL-2-induced proliferation of human T cells significantly without inhibiting the anti-apoptotic effect of IL-2. As Lck is the only Src family...

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

    Science.gov (United States)

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

    2016-02-01

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

  10. Adult neural precursor cells form connexin-dependent networks that improve their survival.

    Science.gov (United States)

    Ravella, Ajaya; Ringstedt, Thomas; Brion, Jean-Pierre; Pandolfo, Massimo; Herlenius, Eric

    2015-10-21

    Establishment of cellular networks and calcium homeostasis are essential for embryonic stem cell proliferation and differentiation. We also hypothesized that adult neural progenitor cells form functional cellular networks relevant for their development. We isolated neuronal progenitor cells from the subventricular zone of 5-week-old mice to investigate the role of gap junctions, calcium homeostasis, and cellular networks in cell differentiation and survival. Western blotting and reverse transcription-PCR showed that the cells expressed the gap junction components connexin 26, 36, 43, and 45, and that expression of connexin 43 increased in early (8 days) differentiated cells. Transmission electron microscopy and immunocytochemistry also indicated that gap junctions were present. Scrape-loading experiments showed dye transfer between cells that could be prevented by gapjunction blockers; thus, functional intercellular gap junctions had been established. However, dye transfer was four times stronger in differentiated cultures, correlating with the increased connexin 43 expression. During time-lapse calcium imaging, both differentiated and undifferentiated cultures showed spontaneous calcium activity that was reduced by gap junction blockers. Cross-correlation analysis of the calcium recordings showed that the cells were interconnected through gap junctions and that the early-differentiated cells were organized in small-world networks. Gap junction blockers did not affect proliferation and differentiation, but resulted in twice as many apoptotic cells. mRNAi knockdown of connexin 43 also doubled the number of apoptotic cells. We conclude that adult neural progenitor cells form networks in vitro that are strengthened during early differentiation by increased expression of connexin 43. The networks are functional and improve cell survival. PMID:26351758

  11. Ras and Rheb Signaling in Survival and Cell Death

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

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

  13. Id1 expression promotes peripheral CD4+ T cell proliferation and survival upon TCR activation without co-stimulation

    International Nuclear Information System (INIS)

    Highlights: •Id1 expression enables naïve T cell proliferation without anti-CD28 co-stimulation. •Id1 expression facilitates T cells survival when stimulated with anti-CD3. •Elevation of IL-2 production by Id1 contributes increased proliferation and survival. •Id1 potentiates NF-κB activation by anti-CD3 stimulation. -- Abstract: Although the role of E proteins in the thymocyte development is well documented, much less is known about their function in peripheral T cells. Here we demonstrated that CD4 promoter-driven transgenic expression of Id1, a naturally occurring dominant-negative inhibitor of E proteins, can substitute for the co-stimulatory signal delivered by CD28 to facilitate the proliferation and survival of naïve CD4+ cells upon anti-CD3 stimulation. We next discovered that IL-2 production and NF-κB activity after anti-CD3 stimulation were significantly elevated in Id1-expressing cells, which may be, at least in part, responsible for the augmentation of their proliferation and survival. Taken together, results from this study suggest an important role of E and Id proteins in peripheral T cell activation. The ability of Id proteins to by-pass co-stimulatory signals to enable T cell activation has significant implications in regulating T cell immunity

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

    International Nuclear Information System (INIS)

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

  15. Aiolos collaborates with Blimp-1 to regulate the survival of multiple myeloma cells.

    Science.gov (United States)

    Hung, K-H; Su, S-T; Chen, C-Y; Hsu, P-H; Huang, S-Y; Wu, W-J; Chen, M-J M; Chen, H-Y; Wu, P-C; Lin, F-R; Tsai, M-D; Lin, K-I

    2016-07-01

    The transcriptional repressor B lymphocyte-induced maturation protein-1 (Blimp-1) has crucial roles in the control of plasma cell differentiation and in maintaining survival of plasma cells. However, how Blimp-1 ensures the survival of plasma cell malignancy, multiple myeloma (MM), has remained elusive. Here we identified Aiolos, an anti-apoptotic transcription factor of MM cells, as a Blimp-1-interacting protein by mass spectrometry. ChIP coupled with DNA microarray was used to profile the global binding of Aiolos and Blimp-1 to endogenous targets in MM cells, which revealed their co-binding to a large number of genes, including apoptosis-related genes. Accordingly, Blimp-1 and Aiolos regulate similar transcriptomes in MM cells. Analysis of the binding motifs for Blimp-1 and Aiolos uncovered a partial motif that was similar across sites for both proteins. Aiolos promotes the binding of Blimp-1 to target genes and thereby enhances Blimp-1-dependent transcriptional repression. Furthermore, treatment with an anti-MM agent, lenalidomide, caused ubiquitination and proteasomal degradation of Blimp-1, leading to the de-repression of a new Blimp-1 direct target, CULLIN 4A (CUL4A), and reduced Aiolos levels. Accordingly, lenalidomide-induced cell death was partially rescued by reintroduction of Blimp-1 or knockdown of CUL4A. Thus, we demonstrated the functional impacts and underlying mechanisms of the interaction between Aiolos and Blimp-1 in maintaining MM cell survival. We also showed that interruption of Blimp-1/Aiolos regulatory pathways contributes to lenalidomide-mediated anti-MM activity. PMID:26823144

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

    International Nuclear Information System (INIS)

    Highlights: ► Unknown cellular mutations complement papillomavirus-induced carcinogenesis. ► Hedgehog pathway components are expressed by cervical cancer cells. ► Hedgehog pathway activators and inhibitors regulate cervical cancer cell biology. ► 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.

  17. 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.

  18. Identification of Progenitor Cell Survival in Peripheral Blood

    International Nuclear Information System (INIS)

    The myeloid progenitors can not survive properly under the usual conditions of blood banking.The aim of work is to assay the survival of myeloid progenitors during varying periods of blood storage, under the usual condition of blood banking. It is an attempt to detect whether or not ,these circulating myeloid progenitors could be stored under the blood banking condition to be used in clinical transplantation protocols to treat a wide variety of refractory diseases.Individual blood samples from forty healthy adults were examined clinically, laboratory and ultrasonography. Peripheral blood mononuclear cells (PBMCs) were isolated using Ficoll-Paque gradients . Serial dilutions of human placental conditioned medium were made, and tested for optimal activity by In vitro cultured technique.This study estimated that the mean levels of absolute number of myeloid progenitors per c.mm. at zero time was 137.7±68.3 (Range 54-297),at day 3 was 71.0±40.2 (Range 54-297), at day 7 was 94.8±45.7 (Range 30 -232) and at day 14 was 45.5±22.7). There was statistically significant decrease in the number of colonies from zero time to day 14. There was statistically significant decrease in the number of myeloid progenitors from zero time to day 14

  19. Resistin is a survival factor for porcine ovarian follicular cells.

    Science.gov (United States)

    Rak, Agnieszka; Drwal, Eliza; Wróbel, Anna; Gregoraszczuk, Ewa Łucja

    2015-10-01

    Previously, we demonstrated the expression of resistin in the porcine ovary, the regulation of its expression and its direct effect on ovarian steroidogenesis. The objective of this study was to examine the effect of resistin on cell proliferation and apoptosis in a co-culture model of porcine granulosa and theca cells. First, we analysed the effect of resistin at 1 and 10  ng/ml alone or in combination with FSH- and IGF1 on ovarian cell proliferation with an alamarBlue assay and protein expression of cyclins A and B using western blot. Next, the mRNA and protein expression of selected pro-apoptotic and pro-survival regulators of cell apoptosis, caspase-9, -8 and -3 activity and DNA fragmentation using real time PCR, western blot, fluorescent assay and an ELISA kit, respectively, were analysed after resistin treatment. Furthermore, we determined the effect of resistin on the protein expression of ERK1/2, Stat and Akt kinase. Using specific inhibitors of these kinases, we also checked caspase-3 activity and protein expression. We found that resistin, at both doses, has no effect on cell proliferation. The results showed that resistin decreased pro-apoptotic genes, which was confirmed on protein expression of selected factors. We demonstrate an inhibitory effect of resistin on caspase activity and DNA fragmentation. Finally, resistin stimulated phosphorylation of the ERK1/2, Stat and Akt and kinases inhibitors reversed resistin action on caspase-3 activity and protein expression to control. All of these results showed that resistin has an inhibitory effect on porcine ovarian cell apoptosis by activation of the MAPK/ERK, JAK/Stat and Akt/PI3 kinase signalling pathways. PMID:26159832

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

    Directory of Open Access Journals (Sweden)

    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.

  1. 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.

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

    DEFF Research Database (Denmark)

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

    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 i....... Amorphous track modelling of luminescence detector efficiency in proton and carbon beams. 4.Tsuruoka C, Suzuki M, Kanai T, et al. LET and ion species dependence for cell killing in normal human skin fibroblasts. Radiat Res. 2005;163:494-500.......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...... factors is the normalization of the energy distribution around the particle tracks to the actual LET value. Later on we check what is the effect of radial dose distribution choice on kappa parameter for different types and energy of ions. Outline References 1.Katz R, Sharma SC.Response of cells to fast...

  3. Survival curves and cell restoration of gamma irradiated chlorella

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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.

  8. 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. PMID:26757251

  9. Tumor cell survival and immune escape mechanisms in classical Hodgkin lymphoma

    NARCIS (Netherlands)

    Liang, Zheng

    2015-01-01

    Tumor cell survival and immune escape mechanisms in classical Hodgkin lymphoma The nature of classical Hodgkin lymphoma (HL), a minority of tumor cells in a reactive background and loss of B cell phenotype, decides its dependence on the microenvironment for signals to contribute to survival and prol

  10. 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.

  11. Dry up and survive: the role of antioxidant defences in anhydrobiotic organisms

    Directory of Open Access Journals (Sweden)

    Lorena Rebecchi

    2013-05-01

    Full Text Available Although the evolution of life has turned oxygen into a vital chemical for aerobic organisms, this element can also have deleterious effects on living systems through the production of oxidative stress. This is a process resulting from an imbalance between the excessive production of Reactive Oxygen Species (ROS and the limited action of antioxidant defences. It is a particularly harmful health risk factor, involved in the development of several chronic human pathologies and believed to play a major role in the ageing process. Consequently aerobic metabolism needs a stringent control of ROS. Water too is essential for life, but some organisms widespread throughout nature have the ability to survive complete desiccation by entering an anhydrobiotic state. The loss of water induces changes in metabolism, cell membrane organization, and molecular composition. In the anhydrobiotic state, high temperatures, high humidity, light exposure, and high oxygen partial pressure negatively affect organism survival and directly influence the time required to reactivate the metabolism after a period of desiccation. These abiotic factors induce damages that are accumulated in proportion to the time spent in the desiccated state, potentially leading to organism death. Oxidative stress seems to be one of the most deleterious damages due to water depletion, therefore anhydrobiosis also needs a stringent control of ROS production. Anhydrobiotic organisms seem to apply two main strategies to cope with the danger of oxygen toxicity, namely an increased efficiency of antioxidant defences and a metabolic control of both energy-production and energy-consuming processes. Experimental studies provide evidence that antioxidant defences such as ROS scavenging enzymes (e.g. peroxidases, catalases, superoxide dismutase, glutathione peroxidases and other molecules (e.g. glutathione, carotenoids, vitamins C and E represent a key group of molecules required for desiccation

  12. P2X7 receptor predicts postoperative cancer-specific survival of patients with clear-cell renal cell carcinoma.

    Science.gov (United States)

    Liu, Zheng; Liu, Yidong; Xu, Le; An, Huimin; Chang, Yuan; Yang, Yuanfeng; Zhang, Weijuan; Xu, Jiejie

    2015-09-01

    The P2X7 receptor, an ATP-gated plasma membrane ion channel, is involved in inflammation, apoptosis and cell proliferation, and thereby plays a crucial role during oncogenic transformation in various malignancies. This study aims to evaluate the impact of P2X7 receptor expression on postoperative cancer-specific survival of patients with clear-cell renal cell carcinoma (ccRCC). A total of 273 patients with ccRCC undergoing nephrectomy at a single institution were retrospectively enrolled in this study, among which 86 patients died of this disease and six patients died of other causes. Clinicopathologic features and cancer-specific survival (CSS) were recorded. P2X7 expression was assessed by immunohistochemistry in clinical specimens. Kaplan-Meier method with log rank test was performed to compare survival curves. Cox regression models were used to evaluate the prognostic values of variables on CSS. Concordance index was calculated to assess prognostic accuracy of prognostic models. Median follow-up period was 90 months (range, 11-120 months). Intratumoral P2X7 expression was significantly lower than peritumoral tissues (P independent prognostic factor for CSS (hazard ratio [HR], 1.693; P = 0.034). The prognostic accuracy of TNM stage, UISS and SSIGN scoring models was improved when intratumoral P2X7 expression was added. Intratumoral P2X7 expression is a potential independent adverse prognostic indicator for postoperative CSS of patients with ccRCC. PMID:26179886

  13. beta1-integrin-mediated signaling essentially contributes to cell survival after radiation-induced genotoxic injury

    DEFF Research Database (Denmark)

    Cordes, N; Seidler, J; Durzok, R; Geinitz, H; Brakebusch, C

    2006-01-01

    Integrin-mediated adhesion to extracellular matrix proteins confers resistance to radiation- or drug-induced genotoxic injury. To analyse the underlying mechanisms specific for beta1-integrins, wild-type beta1A-integrin-expressing GD25beta1A cells were compared to GD25beta1B cells, which express...... findings in tumor cells, human A-172 glioma cells were examined under the same conditions after siRNA-mediated silencing of beta1-integrins. We found that beta1A-integrin-mediated adhesion to fibronectin, collagen-III or beta1-IgG was essential for cell survival after radiation-induced genotoxic injury...... central role of beta1-integrins in Akt- and p130Cas/paxillin-mediated prosurvival signaling. These findings suggest beta1-integrins as critical regulators of cell survival after radiation-induced genotoxic injury. Elucidation of the molecular circuitry of prosurvival beta1-integrin-mediated signaling in...

  14. JNK and macroautophagy activation by bortezomib has a pro-survival effect in primary effusion lymphoma cells.

    Directory of Open Access Journals (Sweden)

    Marisa Granato

    Full Text Available Understanding the mechanisms of autophagy induction and its role during chemotherapeutic treatments is of fundamental importance in order to manipulate it to improve the outcome of chemotherapy. In particular whether the bortezomib-induced autophagy plays a pro-survival or pro-death role is still controversial. In this study we investigated if bortezomib induced endoplasmic reticulum (ER stress and activated autophagy in Primary Effusion Lymphoma (PEL cells and how they influenced cell survival. We found that bortezomib induced up-regulation of the pro-survival and pro-death ER stress molecules BIP and CHOP and activated c-Jun NH2-terminal kinase (JNK, resulting in Bcl-2 phosphorylation and induction of autophagy. JNK and autophagy activation played a pro-survival role in this setting, thus their inhibition increased the bortezomib cytotoxic effect and PARP cleavage in PEL cells. Based on our results we suggest that the combination of bortezomib with JNK or autophagy inhibitors could be exploited to improve the outcome of therapy of this aggressive B cell lymphoma.

  15. Sphingosine kinase expression increases intracellular sphingosine-1-phosphate and promotes cell growth and survival.

    Science.gov (United States)

    Olivera, A; Kohama, T; Edsall, L; Nava, V; Cuvillier, O; Poulton, S; Spiegel, S

    1999-11-01

    Sphingosine-1-phosphate (SPP) is a bioactive lipid that has recently been identified as the ligand for the EDG family of G protein-coupled cell surface receptors. However, the mitogenic and survival effects of exogenous SPP may not correlate with binding to cell-surface receptors (Van Brocklyn, J.R., M.J. Lee, R. Menzeleev, A. Olivera, L. Edsall, O. Cuvillier, D.M. Thomas, P.J.P. Coopman, S. Thangada, T. Hla, and S. Spiegel. 1998. J. Cell Biol. 142:229-240). The recent cloning of sphingosine kinase, a unique lipid kinase responsible for the formation of SPP, has provided a new tool to investigate the role of intracellular SPP. Expression of sphingosine kinase markedly increased SPP levels in NIH 3T3 fibroblasts and HEK293 cells, but no detectable secretion of SPP into the medium was observed. The increased sphingosine kinase activity in NIH 3T3 fibroblasts was sufficient to promote growth in low- serum media, expedite the G(1)/S transition, and increase DNA synthesis and the proportion of cells in the S phase of the cell cycle with a concomitant increase in cell numbers. Transient or stable overexpression of sphingosine kinase in NIH 3T3 fibroblasts or HEK293 cells protected against apoptosis induced by serum deprivation or ceramide elevation. N,N-Dimethylsphingosine, a competitive inhibitor of sphingosine kinase, blocked the effects of sphingosine kinase overexpression on cell proliferation and suppression of apoptosis. In contrast, pertussis toxin did not abrogate these biological responses. In Jurkat T cells, overexpression of sphingosine kinase also suppressed serum deprivation- and ceramide-induced apoptosis and, to a lesser extent, Fas-induced apoptosis, which correlated with inhibition of DEVDase activity, as well as inhibition of the executionary caspase-3. Taken together with ample evidence showing that growth and survival factors activate sphingosine kinase, our results indicate that SPP functions as a second messenger important for growth and survival of

  16. Autologous plasma and its supporting role in fat graft survival: A relevant vector to counteract resorption in lipofilling.

    Science.gov (United States)

    Stillaert, Filip; Depypere, Bernard; Doornaert, Maarten; Creytens, David; De Clercq, Heidi; Cornelissen, Ria; Monstrey, Stan; Blondeel, Phillip

    2016-07-01

    Fat grafting has become a widespread technique for different reconstructive and esthetic purposes. However, the disadvantage of fat grafting is the unpredictable resorption rate that often necessitates repetitive procedures, which in turn may have an impact on the morbidity. During the immediate, post-graft, ischemic period, cells survive due to the process of plasmatic imbibition. This biological phenomenon precedes the ingrowth of neo-capillaries that eventually nourish the graft and help establish a long-term homeostatic equilibrium. Both partners, the graft and the recipient bed, contribute to the revascularization process. Hypothetically, enrichment of the recipient site with autologous plasma could have a beneficial role to enhance fat graft survival. We investigated whether plasma supported the viability of the lipoaspirate (LA) material. Plasma was isolated from blood samples collected from eight patients during the elective lipofilling procedures. An in vitro study assessed the viability of LA cells using plasma as a culture medium compared to the traditional culture media. In vitro analysis confirmed sustained viability of LA cells compared to the standard media and control media during 7 consecutive days. The behavior of the fat grafts in plasma showed similarities with those incubated in the traditional culture media. In future, these findings could be translated to a clinical setting. Plasma is the only autologous substrate available in large quantities in the human body. The addition of the supporting agents, such as plasma, could contribute to a better graft survival with more stable clinical outcomes in the long term. The rationale behind the technique is based on the phenomenon of plasmatic imbibition and the reasoning that the extracellular matrix plays a pivotal role in cellular survival. PMID:27117776

  17. High VRK1 expression contributes to cell proliferation and survival in hepatocellular carcinoma.

    Science.gov (United States)

    Huang, Wei; Cui, Xiaopeng; Chen, Yuyan; Shao, Mengting; Shao, Xian; Shen, Yifen; Liu, Qingqing; Wu, Miaomiao; Liu, Jinxia; Ni, Wenkai; Lu, Cuihua; Wan, Chunhua

    2016-03-01

    VRK1 is a member of the vaccinia-related kinase (VRK) family of serine/threonine protein kinases, which is known to play multiple roles in cellular proliferation, cell cycle regulation and carcinogenesis. However, the expression and physiological significance of VRK1 in hepatocellular carcinoma (HCC) remain unclear. In this study, we aimed to investigate the potential role of VRK1 in the development and progression of HCC. Western blot and immunohistochemical analysis revealed that VRK1 was highly expressed in HCC tissues and cell lines, compared with adjacent nontumorous tissues and LO2 normal hepatocytes. Meanwhile, clinicopathological analysis showed that VRK1 was significantly associated with AJCC stage, Ki-67 and a poor prognosis in HCC specimens. Univariate and multivariate analysis showed that VRK1 could serve as an independent prognostic indicator of HCC patients' survival. Furthermore, we found that VRK1 was lowly expressed in serum-starved Huh7 cells, and was progressively increased after serum-refeeding. Finally, flow cytometry, CCK-8 and colony formation assay indicated that the depletion of VRK1 could retard cell cycle progression and reduce cells proliferation in HCC cells. On the basis of these findings, we conclude that VRK1 may be a candidate prognostic biomarker as well as a potential therapeutical target of HCC. PMID:26706601

  18. 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

    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......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...... treated with SI to induce cell death. Cells were transfected with an iPLA₂-VIA promoter-luciferase construct to evaluate the regulation of iPLA-VIA after exposure to SI. PCR analysis, western blot analysis, and activity assays were performed to evaluate the mRNA level, protein level, and activity levels...

  19. 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

    , 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...... disease have a highly increased risk of late toxicity and death as a result of causes other than GCC. Therefore, they should be candidates for life-long follow-up. The IPFSG classification was confirmed in this unselected population.......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...

  20. Improvement of Cell Survival During Human Pluripotent Stem Cell Definitive Endoderm Differentiation.

    Science.gov (United States)

    Wang, Han; Luo, Xie; Yao, Li; Lehman, Donna M; Wang, Pei

    2015-11-01

    Definitive endoderm (DE) is a vital precursor for internal organs such as liver and pancreas. Efficient protocol to differentiate human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs) to DE is essential for regenerative medicine and for modeling diseases; yet, poor cell survival during DE differentiation remains unsolved. In this study, our use of B27 supplement in modified differentiation protocols has led to a substantial improvement. We used an SOX17-enhanced green fluorescent protein (eGFP) reporter hESC line to compare and modify established DE differentiation protocols. Both total live cell numbers and the percentages of eGFP-positive cells were used to assess differentiation efficiency. Among tested protocols, three modified protocols with serum-free B27 supplement were developed to generate a high number of DE cells. Massive cell death was avoided during DE differentiation and the percentage of DE cells remained high. When the resulting DE cells were further differentiated toward the pancreatic lineage, the expression of pancreatic-specific markers was significantly increased. Similar high DE differentiation efficiency was observed in H1 hESCs and iPSCs through the modified protocols. In B27 components, bovine serum albumin was found to facilitate DE differentiation and cell survival. Using our modified DE differentiation protocols, satisfactory quantities of quality DE can be produced as primary material for further endoderm lineage differentiation. PMID:26132288

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Impact of Neoadjuvant Radiation on Survival in Stage III Non-Small-Cell Lung Cancer

    International Nuclear Information System (INIS)

    Purpose: The role of surgery in Stage III non-small-cell lung cancer (NSCLC) is controversial. This study was undertaken to assess the impact of neoadjuvant radiation therapy for Stage III NSCLC. Methods and Materials: This was a retrospective study from the Surveillance, Epidemiology, and End Results (SEER) database that included patients who were 18 years and older with NSCLC classified as Stage III and who underwent definitive therapy from 1988 to 2004. Patients were characterized by type of treatment received. Survival functions were estimated by the Kaplan-Meier method, and Cox regression model was used to analyze trends in overall (OS) and cause-specific survival (CSS). Results: A total of 48,131 patients were selected, with a median follow-up of 10 months (range, 0-203 months). By type of treatment, the 3-year OS was 10% with radiation therapy (RT), 37% with surgery (S), 34% with surgery and postoperative radiation (S-RT), and 45% with neoadjuvant radiation followed by surgery (Neo-RT) (p = 0.0001). Multivariable Cox model identified sex, race, laterality, T stage, N stage, and type of treatment as factors affecting survival. Estimated hazard ratios (HR) adjusted for other variables in regression model showed the types of treatment: S (HR, 1.3; 95% confidence interval [CI], 1.2-1.4), S-RT (HR, 1.2; 95% CI, 1.1-1.3), and RT (HR, 2.3; 95% CI, 2.15-2.53) were associated with significantly worse overall survival when compared with Neo-RT (p = 0.0001). Conclusion: This population based study demonstrates that patients with Stage III NSCLC receiving Neo-RT had significantly improved overall survival when compared with other treatment groups.

  3. Critical Role of Antimicrobial Peptide Cathelicidin for Controlling Helicobacter pylori Survival and Infection.

    Science.gov (United States)

    Zhang, Lin; Wu, William K K; Gallo, Richard L; Fang, Evandro F; Hu, Wei; Ling, Thomas K W; Shen, Jing; Chan, Ruby L Y; Lu, Lan; Luo, Xiao M; Li, Ming X; Chan, Kam M; Yu, Jun; Wong, Vincent W S; Ng, Siew C; Wong, Sunny H; Chan, Francis K L; Sung, Joseph J Y; Chan, Matthew T V; Cho, Chi H

    2016-02-15

    The antimicrobial peptide cathelicidin is critical for protection against different kinds of microbial infection. This study sought to elucidate the protective action of cathelicidin against Helicobacter pylori infection and its associated gastritis. Exogenous cathelicidin was found to inhibit H. pylori growth, destroy the bacteria biofilm, and induce morphological alterations in H. pylori membrane. Additionally, knockdown of endogenous cathelicidin in human gastric epithelial HFE-145 cells markedly increased the intracellular survival of H. pylori. Consistently, cathelicidin knockout mice exhibited stronger H. pylori colonization, higher expression of proinflammatory cytokines IL-6, IL-1β, and ICAM1, and lower expression of the anti-inflammatory cytokine IL-10 in the gastric mucosa upon H. pylori infection. In wild-type mice, H. pylori infection also stimulated gastric epithelium-derived cathelicidin production. Importantly, pretreatment with bioengineered Lactococcus lactis that actively secretes cathelicidin significantly increased mucosal cathelicidin levels and reduced H. pylori infection and the associated inflammation. Moreover, cathelicidin strengthened the barrier function of gastric mucosa by stimulating mucus synthesis. Collectively, these findings indicate that cathelicidin plays a significant role as a potential natural antibiotic for H. pylori clearance and a therapeutic agent for chronic gastritis. PMID:26800870

  4. Role of autophagy in the regulation of epithelial cell junctions.

    Science.gov (United States)

    Nighot, Prashant; Ma, Thomas

    2016-01-01

    Autophagy is a cell survival mechanism by which bulk cytoplasmic material, including soluble macromolecules and organelles, is targeted for lysosomal degradation. The role of autophagy in diverse cellular processes such as metabolic stress, neurodegeneration, cancer, aging, immunity, and inflammatory diseases is being increasingly recognized. Epithelial cell junctions play an integral role in the cell homeostasis via physical binding, regulating paracellular pathways, integrating extracellular cues into intracellular signaling, and cell-cell communication. Recent data indicates that cell junction composition is very dynamic. The junctional protein complexes are actively regulated in response to various intra- and extra-cellular clues by intracellular trafficking and degradation pathways. This review discusses the recent and emerging information on how autophagy regulates various epithelial cell junctions. The knowledge of autophagy regulation of epithelial junctions will provide further rationale for targeting autophagy in a wide variety of human disease conditions. PMID:27583189

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

    International Nuclear Information System (INIS)

    Recombinant rat stem cell factor (SCF) has been shown to decrease lethality in mice exposed to total-body irradiation (TBI) in the lower range of lethality through radioprotection of hematopoietic stem cells and acceleration of bone marrow repopulation. This study evaluates the effect of SCF on the survival of the intestinal mucosal stem cell after TBI. This non-hematopoietic cell is clinically relevant. Gastrointestinal toxicity is common during and after abdominal and pelvic radiation therapy and limits the radiation dose in these regions. As observed with bone marrow, the administration of SCF to mice prior to TBI enhanced the survival of mouse duodenal crypt stem cells. The maximum enhancement of survival was seen when 100 μ/kg of SCF was given intraperitoneally 8 h before irradiation. This regimen increased the survival of duodenal crypt stem cells after 12.0 Gy TBI from 22.5 ± 0.7 per duodenal cross section for controls to 30.0 ± 1.7 after treatment with SCF (P=0.03). The TBI dose producing 50% mortality of 6 days (LD50/6) was increased from 14.9 Gy for control mice to 19.0 Gy for mice treated with SCF (dose modification factor = 1.28). These findings demonstrate that SCF (dose modification factor = 1.28). These findings demonstrate that SCF has radioprotective effects on a non-hematopoietic stem cell population and suggest that SCF may be of clinical value in preventing radiation injury to the intestine. 29 refs., 4 figs

  6. 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. PMID:27210806

  7. PIAS3 expression in squamous cell lung cancer is low and predicts overall survival

    International Nuclear Information System (INIS)

    Unlike lung adenocarcinoma, little progress has been made in the treatment of squamous cell lung carcinoma (SCC). The Cancer Genome Atlas (TCGA) has recently reported that receptor tyrosine kinase signaling pathways are altered in 26% of SCC tumors, validating the importance of downstream Signal Transducers and Activators of Transcription 3 (STAT3) activity as a prime therapeutic target in this cancer. In the present report we examine the status of an endogenous inhibitor of STAT3, called Protein Inhibitor of Activated STAT3 (PIAS3), in SCC and its potential role in this disease. We examine PIAS3 expression in SCC tumors and cell lines by immunohistochemistry of a tissue microarray and western blotting. PIAS3 mRNA expression and survival data are analyzed in the TCGA data set. SCC cell lines are treated with curcumin to regulate PIAS3 expression and cell growth. PIAS3 protein expression is decreased in a majority of lung SCC tumors and cell lines. Analysis of PIAS3 mRNA transcript levels demonstrated that low PIAS3 levels predicted poor survival; Cox regression analysis revealed a hazard ratio of 0.57 (95% CI: 0.37–0.87), indicating a decrease in the risk of death by 43% for every unit elevation in PIAS3 gene expression. Curcumin treatment increased endogenous PIAS3 expression and decreased cell growth and viability in Calu-1 cells, a model of SCC. Our results implicate PIAS3 loss in the pathology of lung SCC and raise the therapeutic possibility of upregulating PIAS3 expression as a single target that can suppress signaling from the multiple receptor tyrosine kinase receptors found to be amplified in SCC

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

    International Nuclear Information System (INIS)

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

  9. 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.

  10. 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.

  11. 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.

  12. EMR2 Receptor Ligation Modulates Cytokine Secretion Profiles and Cell Survival of Lipopolysaccharide-treated Neutrophils

    Directory of Open Access Journals (Sweden)

    Tzu-Ying Chenee

    2011-10-01

    Full Text Available Background: Epidermal growth factor (EGF-like module-containing mucin-like hormonereceptor-like 2 (EMR2 is an adhesion G protein-coupled receptor previouslyshown to potentiate neutrophil responses to a number of inflammatory stimuli. EMR2 activation promotes neutrophil adhesion and migration, and augments production of reactive oxygen species and degranulation. In this study,we examined the effect of EMR2 ligation by its specific antibody on thecytokine expression profile and cell survival of lipopolysaccharide (LPS-treated neutrophils.Methods: Neutrophils were treated with LPS in the absence or presence of the antiEMR2 mAb, 2A1. Cell apoptosis was determined by flow cytometry analysisusing annexin-V and propidium iodide staining. Cell supernatants were collected for the detection of cytokine secretion by enzyme-linked immunosorbent assay.Results: We confirmed the specific priming effect of EMR2 on the response of neutrophils to formyl-Met-Leu-Phe by measuring the production of reactiveoxygen species. Furthermore, we showed that EMR2 ligation suppressesLPS-induced neutrophil survival. In addition, we demonstrated that ligationof EMR2 changes the secretion profiles of multiple cytokines, includinginterleukin (IL-6, IL-8, and monocyte chemotactic protein-1. Finally, higherlevels of EMR2 were detected on neutrophils of liver cirrhosis patients andwere correlated to a pro-apoptotic phenotype.Conclusion: Collectively, the present data indicate a functional role for EMR2 in themodulation of neutrophil activation during inflammation.

  13. Enhanced CLIP uncovers IMP protein-RNA targets in human pluripotent stem cells important for cell adhesion and survival

    Science.gov (United States)

    Conway, Anne E.; Van Nostrand, Eric L.; Pratt, Gabriel A.; Aigner, Stefan; Wilbert, Melissa L.; Sundararaman, Balaji; Freese, Peter; Lambert, Nicole J.; Sathe, Shashank; Liang, Tiffany Y.; Essex, Anthony; Landais, Severine; Burge, Christopher B.; Jones, D. Leanne; Yeo, Gene W.

    2016-01-01

    SUMMARY Human pluripotent stem cells (hPSCs) require precise control of post-transcriptional RNA networks to maintain proliferation and survival. Using enhanced UV crosslinking and immunoprecipitation (eCLIP), we identify RNA targets of the IMP/IGF2BP family of RNA-binding proteins in hPSCs. At the broad region- and binding site-level IMP1 and IMP2 show reproducible binding to a large and overlapping set of 3′UTR-enriched targets. RNA Bind-N-Seq applied to recombinant full-length IMP1 and IMP2 reveals CA-rich motifs that are enriched in eCLIP-defined binding sites. We observe that IMP1 loss in hPSCs recapitulates IMP1 phenotypes, including a reduction in cell adhesion and an increase in cell death. For cell adhesion, in hPSCs we find IMP1 maintains levels of integrin mRNA, specifically regulating RNA stability of ITGB5. Additionally, we show IMP1 can be linked to hPSC survival via direct target BCL2. Thus, transcriptome-wide binding profiles identify hPSC targets modulating well-characterized IMP1 roles. PMID:27068461

  14. Lipoic acid enhances survival of transplanted neural stem cells by reducing transplantation-associated injury

    OpenAIRE

    Wu, Ping

    2013-01-01

    Junling Gao,1,* Jason R Thonhoff,1,2,* Tiffany J Dunn,1 Ping Wu1 1Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA; 2Department of Neurology, The Methodist Hospital, Houston, TX, USA *These authors contributed equally to this work Abstract: The efficacy of stem cell-based therapy for neurological diseases depends highly on cell survival post-transplantation. One of the key factors affecting cell survival is the grafting procedure. The curren...

  15. ORP4L is essential for T-cell acute lymphoblastic leukemia cell survival.

    Science.gov (United States)

    Zhong, Wenbin; Yi, Qing; Xu, Bing; Li, Shiqian; Wang, Tong; Liu, Fupei; Zhu, Biying; Hoffmann, Peter R; Ji, Guangju; Lei, Pingsheng; Li, Guoping; Li, Jiwei; Li, Jian; Olkkonen, Vesa M; Yan, Daoguang

    2016-01-01

    Metabolic pathways are reprogrammed in cancer to support cell survival. Here, we report that T-cell acute lymphoblastic leukemia (T-ALL) cells are characterized by increased oxidative phosphorylation and robust ATP production. We demonstrate that ORP4L is expressed in T-ALL but not normal T-cells and its abundance is proportional to cellular ATP. ORP4L acts as an adaptor/scaffold assembling CD3ɛ, Gαq/11 and PLCβ3 into a complex that activates PLCβ3. PLCβ3 catalyzes IP3 production in T-ALL as opposed to PLCγ1 in normal T-cells. Up-regulation of ORP4L thus results in a switch in the enzyme responsible for IP3-induced endoplasmic reticulum Ca(2+) release and oxidative phosphorylation. ORP4L knockdown results in suboptimal bioenergetics, cell death and abrogation of T-ALL engraftment in vivo. In summary, we uncovered a signalling pathway operating specifically in T-ALL cells in which ORP4L mediates G protein-coupled ligand-induced PLCβ3 activation, resulting in an increase of mitochondrial respiration for cell survival. Targeting ORP4L might represent a promising approach for T-ALL treatment. PMID:27581363

  16. Regulation of proliferation-survival decisions is controlled by FGF1 secretion in retinal pigmented epithelial cells.

    Science.gov (United States)

    Bryckaert, M; Guillonneau, X; Hecquet, C; Perani, P; Courtois, Y; Mascarelli, F

    2000-10-01

    Fibroblast growth factor 1 (FGF1) induces proliferation and differentiation in a wide variety of cells of mesodermal and neuroectodermal origin. FGF1 has no 'classical' signal sequence to direct its secretion, and there has been considerable debate concerning FGF1 secretion and its role in the biological activities of FGF1. We investigated the effects of FGF1 secretion and the signalling induced by signal peptide (SP)-containing FGFI and SP-less FGF1, on the proliferation and the apoptosis in retinal pigmented epithelial (RPE) cells. Primary RPE cell cultures were transfected with FGF1 (FGF1 cells) and SP-FGF1 (SP-FGF1 cells) cDNAs. SP-FGF1 cells secreted large amount of FGF1 and actively proliferated, whereas FGF1 and control cells did not. Secreted FGF1 induced short-term activation of both FGFR1 and ERK2, which were required for cell proliferation. In contrast, SP-FGF1 cells stopped secreting FGF1 and died rapidly, if cultured in the absence of serum. Surprisingly, FGF1 cells, but not control cells, secreted FGF1 and were resistant to apoptosis induced by serum depletion. Secreted FGF1 induced long-term activation of FGFR1 and ERK2, which was necessary to induce a constant and high level of Bcl-x production, and to induce cell survival in FGFI cells. Downregulation of ERK2 and Bcl-x increased apoptosis. Thus, the proliferation and survival activities of FGF1 depend on the secretion of FGF1 which is determined by the cell culture conditions. Cell proliferation was SP-dependent, whereas cell survival was not. The signal peptide controls the level and duration, 'whispering or shouting', of ERK2 activation cells which determines FGF1 biological function and may have important implications for anti-degenerative and anti-proliferative treatments. PMID:11039909

  17. 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.

  18. The effect of heat on Na+/H+ antiport function and survival in mammalian cells

    International Nuclear Information System (INIS)

    Purpose: Because intracellular pH (pHi) is a determinant of thermosensitivity, it is important to understand the relationship between heat cytotoxicity and the mechanisms responsible for pHi regulation, such as the Na+/H+ antiport. The objective of this study is to elucidate the relationship between heat damage and Na+/H+ antiport activity. Methods and Materials: Various cell lines, EMT6, RIF-1, and its thermoresistant variant TR-4, and CCL39, and its variant that lacks the Na+/H+ antiport (PS120), were all heated using a water bath. Parallel assessments of antiport function and pHi were made using the fluorescent dye 2,7-biscarboxyethyl-5(6)-carboxyfluorescein (BCECF). Results: Exposure of EMT6 cells to 43-46 deg. C for 30-60 min caused progressive decline in antiport activity, in parallel with cytotoxicity. When the same degree of cytotoxicity was induced by ionizing radiation, no alteration in Na+/H+ antiport function was observed. Despite a 10-fold lower survival in RIF-1 compared to TR-4 cells after heating, there was no difference in the thermosensitivity of their antiports. Antiport activity in the TR-4 cells, however, was higher than that of RIF-1 cells both before and during heating. Intracellular pH for TR-4 cells decreased minimally during heating, in contrast to a decline of 1 pH unit in RIF-1 cells despite similar relative levels of antiport activity, suggesting that in this pair of cell lines, antiport activity does not play a major pHi regulatory role. PS120 and CCL39 cells had similar survival levels when heated at pHe 7.2 in the presence of NaHCO3, which allows function of the other major regulator of pHi, the Na+-dependent HCO3-/Cl- exchanger. This occurred despite a drop in pHi in the PS120 cells during heating. A reduced survival was observed, however, in PS120 cells after 43 deg. C for 30-60 min at either pHe 6.5 or pHe 7.2 in the absence of NaHCO3. Intracellular pH for both lines decreased with increasing duration of heating under the various

  19. 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. PMID:27543869

  20. Cyclooxygenase-2 in tumor-associated macrophages promotes breast cancer cell survival by triggering a positive-feedback loop between macrophages and cancer cells

    OpenAIRE

    Li, Hongzhong; Yang, Bing; Huang, Jing; Lin, Yong; Xiang, Tingxiu; Wan, Jingyuan; Li, Hongyuan; Chouaib, Salem; Ren, Guosheng

    2015-01-01

    Tumor-associated macrophages (TAMs) play an important role in cancer cell survival, however, the mechanism of which remains elusive. In this study, we found that COX-2 was abundantly expressed in breast TAMs, which was correlated to poor prognosis in breast cancer patients. Ectopic over-expression of COX-2 in TAMs enhanced breast cancer cell survival both in vitro and in vivo. COX-2 in TAMs was determined to be essential for the induction and maintenance of M2-phenotype macrophage polarity. C...

  1. 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. PMID:20015867

  2. Radiobiology goes 3D: How ECM and cell morphology impact on cell survival after irradiation

    International Nuclear Information System (INIS)

    Translational research is essential to find new therapeutic approaches to improve cancer patient survival. Despite extensive efforts in preclinical studies, many novel therapies fail to turn out to be translational from bench to beside. Therefore, new models better reflecting the conditions in vivo are needed to generate results, which transfer reliably into the clinic. The use of three-dimensional (3D) cell culture models has provided new emerging insights into the understanding of cellular behavior upon cancer therapies. Interestingly, cells cultured in a 3D extracellular matrix are more radio- and chemoresistant than cells grown under conventional 2D conditions. In this review, we summarize and discuss underlying mechanisms of this phenomenon including integrin-mediated cell-matrix interactions, cell shape, nuclear organization and chromatin structure. Identifying the molecular differences between 2D and 3D cultured cells will offer the opportunity to improve our research and widen our therapeutic possibilities against cancer.

  3. Social isolation increases cell proliferation in male and cell survival in female California mice (Peromyscus californicus).

    Science.gov (United States)

    Ruscio, Michael G; Bradley King, S; Haun, Harold L

    2015-11-01

    Social environment has direct effects on an animal's behavior, physiology and neurobiology. In particular, adult neurogenesis is notably affected by a variety of social manipulations, including social isolation. We hypothesized that social isolation should have particularly acute effects on neurogenesis in a highly social (monogamous and bi-parental) species such as Peromyscus californicus, the California mouse. Adult male and female P. californicus mice were housed in isolation or in same-sex pairs for 4 or 24 days. At the end of each period, either cell proliferation or cell survival was quantified with BrdU label and neuronal markers (either TuJ1 or NeuN). After 4 days, isolated males had greater cellular proliferation in the dentate gyrus of the hippocampus (DG) than pair housed males. After 24 days, isolate females demonstrated greater cell survival in the DG than paired females. Males demonstrated a similar, but non-significant pattern. No differences in cellular proliferation or cell survival were found in the subventricular zone (SVZ), or medial amygdala (MeA). These results add to the evidence which demonstrates that neurogenic responses to environmental conditions are not identical across species. These data may be critical in understanding the functional significance of neurogenesis as it relates to the interactions between social systems, social environment and the display of social behaviors. PMID:26342752

  4. 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.

  5. Specific silencing of the REST target genes in insulin-secreting cells uncovers their participation in beta cell survival.

    Science.gov (United States)

    Martin, David; Allagnat, Florent; Gesina, Emilie; Caille, Dorothee; Gjinovci, Asllan; Waeber, Gerard; Meda, Paolo; Haefliger, Jacques-Antoine

    2012-01-01

    The absence of the transcriptional repressor RE-1 Silencing Transcription Factor (REST) in insulin-secreting beta cells is a major cue for the specific expression of a large number of genes. These REST target genes were largely ascribed to a function of neurotransmission in a neuronal context, whereas their role in pancreatic beta cells has been poorly explored. To identify their functional significance, we have generated transgenic mice expressing REST in beta cells (RIP-REST mice), and previously discovered that REST target genes are essential to insulin exocytosis. Herein we characterized a novel line of RIP-REST mice featuring diabetes. In diabetic RIP-REST mice, high levels of REST were associated with postnatal beta cell apoptosis, which resulted in gradual beta cell loss and sustained hyperglycemia in adults. Moreover, adenoviral REST transduction in INS-1E cells led to increased cell death under control conditions, and sensitized cells to death induced by cytokines. Screening for REST target genes identified several anti-apoptotic genes bearing the binding motif RE-1 that were downregulated upon REST expression in INS-1E cells, including Gjd2, Mapk8ip1, Irs2, Ptprn, and Cdk5r2. Decreased levels of Cdk5r2 in beta cells of RIP-REST mice further confirmed that it is controlled by REST, in vivo. Using siRNA-mediated knock-down in INS-1E cells, we showed that Cdk5r2 protects beta cells against cytokines and palmitate-induced apoptosis. Together, these data document that a set of REST target genes, including Cdk5r2, is important for beta cell survival. PMID:23029270

  6. Specific silencing of the REST target genes in insulin-secreting cells uncovers their participation in beta cell survival.

    Directory of Open Access Journals (Sweden)

    David Martin

    Full Text Available The absence of the transcriptional repressor RE-1 Silencing Transcription Factor (REST in insulin-secreting beta cells is a major cue for the specific expression of a large number of genes. These REST target genes were largely ascribed to a function of neurotransmission in a neuronal context, whereas their role in pancreatic beta cells has been poorly explored. To identify their functional significance, we have generated transgenic mice expressing REST in beta cells (RIP-REST mice, and previously discovered that REST target genes are essential to insulin exocytosis. Herein we characterized a novel line of RIP-REST mice featuring diabetes. In diabetic RIP-REST mice, high levels of REST were associated with postnatal beta cell apoptosis, which resulted in gradual beta cell loss and sustained hyperglycemia in adults. Moreover, adenoviral REST transduction in INS-1E cells led to increased cell death under control conditions, and sensitized cells to death induced by cytokines. Screening for REST target genes identified several anti-apoptotic genes bearing the binding motif RE-1 that were downregulated upon REST expression in INS-1E cells, including Gjd2, Mapk8ip1, Irs2, Ptprn, and Cdk5r2. Decreased levels of Cdk5r2 in beta cells of RIP-REST mice further confirmed that it is controlled by REST, in vivo. Using siRNA-mediated knock-down in INS-1E cells, we showed that Cdk5r2 protects beta cells against cytokines and palmitate-induced apoptosis. Together, these data document that a set of REST target genes, including Cdk5r2, is important for beta cell survival.

  7. Radiation-induced autophagy promotes esophageal squamous cell carcinoma cell survival via the LKB1 pathway.

    Science.gov (United States)

    Lu, Chi; Xie, Conghua

    2016-06-01

    Radiotherapy is an important treatment modality for esophageal cancer; however, the clinical efficacy of radiotherapy is limited by tumor radioresistance. In the present study, we explored the hypothesis that radiation induces tumor cell autophagy as a cytoprotective adaptive response, which depends on liver kinase B1 (LKB1) also known as serine/threonine kinase 11 (STK11). Radiation-induced Eca-109 cell autophagy was found to be dependent on signaling through the LKB1 pathway, and autophagy inhibitors that disrupted radiation-induced Eca-109 cell autophagy increased cell cycle arrest and cell death in vitro. Inhibition of autophagy also reduced the clonogenic survival of the Eca-109 cells. When treated with radiation alone, human esophageal carcinoma xenografts showed increased LC3B and p-LKB1 expression, which was decreased by the autophagy inhibitor chloroquine. In vivo inhibition of autophagy disrupted tumor growth and increased tumor apoptosis when combined with 6 Gy of ionizing radiation. In summary, our findings elucidate a novel mechanism of resistance to radiotherapy in which radiation-induced autophagy, via the LKB1 pathway, promotes tumor cell survival. This indicates that inhibition of autophagy can serve as an adjuvant treatment to improve the curative effect of radiotherapy. PMID:27109915

  8. Role of BRCA2 mutation status on overall survival among breast cancer patients from Sardinia

    International Nuclear Information System (INIS)

    Germline mutations in BRCA1 or BRCA2 genes have been demonstrated to increase the risk of developing breast cancer. Conversely, the impact of BRCA mutations on prognosis and survival of breast cancer patients is still debated. In this study, we investigated the role of such mutations on breast cancer-specific survival among patients from North Sardinia. Among incident cases during the period 1997–2002, a total of 512 breast cancer patients gave their consent to undergo BRCA mutation screening by DHPLC analysis and automated DNA sequencing. The Hakulinen, Kaplan-Meier, and Cox regression methods were used for both relative survival assessment and statistical analysis. In our series, patients carrying a germline mutation in coding regions and splice boundaries of BRCA1 and BRCA2 genes were 48/512 (9%). Effect on overall survival was evaluated taking into consideration BRCA2 carriers, who represented the vast majority (44/48; 92%) of mutation-positive patients. A lower breast cancer-specific overall survival rate was observed in BRCA2 mutation carriers after the first two years from diagnosis. However, survival rates were similar in both groups after five years from diagnosis. No significant difference was found for age of onset, disease stage, and primary tumour histopathology between the two subsets. In Sardinian breast cancer population, BRCA2 was the most affected gene and the effects of BRCA2 germline mutations on patients' survival were demonstrated to vary within the first two years from diagnosis. After a longer follow-up observation, breast cancer-specific rates of death were instead similar for BRCA2 mutation carriers and non-carriers

  9. The importance of actual tumor growth rate on disease free survival and overall survival in laryngeal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Background and purpose: Evaluation of the variation in tumor growth rate and the influence of tumor growth rate on disease free survival (DFS) and overall survival (OS) in laryngeal squamous cell carcinoma (LSCC). Material and methods: We delineated tumor volume on a diagnostic and planning CT scan in 131 patients with laryngeal squamous cell carcinoma and calculated the tumor growth rate. Primary endpoint was DFS. Follow up data were collected retrospectively. Results: A large variation in tumor growth rate was seen. When dichotomized with a cut-off point of −0.3 ln(cc/day), we found a significant association between high growth rate and worse DFS (p = 0.008) and OS (p = 0.013). After stepwise adjustment for potential confounders (age, differentiation and tumor volume) this significant association persisted. However, after adjustment of N-stage association disappeared. Exploratory analyses suggested a strong association between N-stage and tumor growth rate. Conclusions: In laryngeal squamous cell carcinoma, there is a large variation in tumor growth rate. This tumor growth rate seems to be an important factor in disease free survival and OS. This tumor growth rate is independent of age, differentiation and tumor volume associated with DFS, but N-stage seems to be a more important risk factor

  10. Measurement of cell mediated cytotoxicity by post-labeling surviving target cells

    International Nuclear Information System (INIS)

    The 51Cr release assay (CRA) is the commonly accepted technique for measurement of cell mediated cytotoxicity. This assay shows some disadvantages when mononucleated cells of human peripheral blood (MNC) are used as effector and target cells. The uptake of 51Cr by PHA stimulated lymphocytes is low compared to the spontaneous release. In an attempt to develop a cytotoxicity assay suitable for human lymphocytes we used 14C-TdR to label target cells surviving after contact with effector cells. Cytotoxic lymphocytes were generated by incubation of MNC with irradiated allogeneic MNC for 6 days. On day 6 the effector cells are irradiated and cocultured with PHA stimulated target cells. Twenty-four hours later 14C-TdR is added. After an additional 24 h the cultures are harvested and 14C-TdR taken up by target cells is measured. It is shown that the effector cells are still cytotoxic after irradiation. These cells do not take up 14C-TdR. Cell-free supernatants do not influence the uptake of 14C-TdR by target cells. The results obtained with this assay correlate very well those obtained by the CRA, if the spontaneous release does not exceed 30%. (author)

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

    Directory of Open Access Journals (Sweden)

    Soares Fernando A

    2011-04-01

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

  12. In vitro oxygen-dependent survival of two human cell lines after combined radiations tirapazamin and cisplatin

    International Nuclear Information System (INIS)

    Recent data have shown that the in vitro and in vivo cytotoxicity of bioreductive drugs could be significantly cytotoxicity of bioreductive drugs could be significantly increased by combination with ionising radiation or chemotherapy. Various parameters such as oxygen tension and timing of administration of the drugs could play a crucial role in the efficacy of combined treatment modalities. The aim of this study was to define the oxygen dependency of cell survival after in vitro irradiation and incubation with tirapazamin, a bioreductive drug, and cisplatin given alone or simultaneously. Two human cell lines were studied: one cell line sensitive to tirapazamin, Na11+, a pigmented melanoma with a high percentage of hypoxic cells, and a less sensitive cell line to tirapazamin, HRT18, a rectal adenocarcinoma. Gas changes were made to study cell survival at four different oxygen concentrations (pO2): air (20.9 % O2), 10.2 and 0.2 %. Cells were incubated with tirapazamin and cisplatin alone or combined for one hour at 37 deg C, then irradiated and cultured. For Na11+, cell survival after irradiation was comparable in air and at 10 % oxygen with the two drugs given alone or combined. At 2 and 0.2 % oxygen, cell killing was largely increased by tirapazamin and was not modified by the addition of cisplatin. For HRT18, cell survival was not modified when cisplatin was added to radiation, whatever the oxygen partial pressure. At low pO2 (2 and 0.2 %) the cytotoxic effect of tirapazamin was not significantly decreased by the addition of cisplatin. When cytotoxic and bioreductive drugs are combined to radiation, the magnitude of the observed effect is highly dependent on the partial oxygen pressure and on the sensitivity of the cell line to the individual drugs. This has very important implications for clinical strategies based on combined chemo-radiotherapy. (authors)

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

    International Nuclear Information System (INIS)

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

  14. Mitochondrial Uncoupling Protein 2 (UCP2) Regulates Retinal Ganglion Cell Number and Survival.

    Science.gov (United States)

    Barnstable, Colin J; Reddy, Rajini; Li, Hong; Horvath, Tamas L

    2016-04-01

    In the brain, mitochondrial uncoupling protein 2 (UCP2) has emerged as a stress signal associated with neuronal survival. In the retina, UCP2 is expressed primarily by retinal ganglion cells. Here, we investigated the functional relevance of UCP2 in the mouse retina. Increased expression of UCP2 significantly reduced apoptosis during the critical developmental period resulting in elevated numbers of retinal ganglion cells in the adult. Elevated UCP2 levels also protected against excitotoxic cell death induced by intraocular injection of either NMDA or kainic acid. In monolayer cultures of retinal cells, elevated UCP2 levels increased cell survival and rendered the cells independent of the survival-promoting effects of the neurotrophic factors BDNF and CNTF. Taken together, these data implicate UCP2 as an important regulator of retinal neuron survival both during development and in adult animals. PMID:26846222

  15. Importance of RpoS and Dps in Survival of Exposure of Both Exponential- and Stationary-Phase Escherichia coli Cells to the Electrophile N-Ethylmaleimide

    OpenAIRE

    Ferguson, G. P.; Creighton, R. I.; Nikolaev, Y; Booth, I R

    1998-01-01

    The mechanisms by which Escherichia coli cells survive exposure to the toxic electrophile N-ethylmaleimide (NEM) have been investigated. Stationary-phase E. coli cells were more resistant to NEM than exponential-phase cells. The KefB and KefC systems were found to play an important role in protecting both exponential- and stationary-phase cells against NEM. Additionally, RpoS and the DNA-binding protein Dps aided the survival of both exponential- and stationary-phase cells against NEM. Double...

  16. Extracellular vesicles from a muscle cell line (C2C12 enhance cell survival and neurite outgrowth of a motor neuron cell line (NSC-34

    Directory of Open Access Journals (Sweden)

    Roger D. Madison

    2014-02-01

    Full Text Available Introduction: There is renewed interest in extracellular vesicles over the past decade or 2 after initially being thought of as simple cellular garbage cans to rid cells of unwanted components. Although there has been intense research into the role of extracellular vesicles in the fields of tumour and stem cell biology, the possible role of extracellular vesicles in nerve regeneration is just in its infancy. Background: When a peripheral nerve is damaged, the communication between spinal cord motor neurons and their target muscles is disrupted and the result can be the loss of coordinated muscle movement. Despite state-of-the-art surgical procedures only approximately 10% of adults will recover full function after peripheral nerve repair. To improve upon such results will require a better understanding of the basic mechanisms that influence axon outgrowth and the interplay between the parent motor neuron and the distal end organ of muscle. It has previously been shown that extracellular vesicles are immunologically tolerated, display targeting ligands on their surface, and can be delivered in vivo to selected cell populations. All of these characteristics suggest that extracellular vesicles could play a significant role in nerve regeneration. Methods: We have carried out studies using 2 very well characterized cell lines, the C2C12 muscle cell line and the motor neuron cell line NSC-34 to ask the question: Do extracellular vesicles from muscle influence cell survival and/or neurite outgrowth of motor neurons? Conclusion: Our results show striking effects of extracellular vesicles derived from the muscle cell line on the motor neuron cell line in terms of neurite outgrowth and survival.

  17. Cell Survival and Apoptosis Signaling as Therapeutic Target for Cancer: Marine Bioactive Compounds

    OpenAIRE

    Kim Se-Kwon; Senthilkumar Kalimuthu

    2013-01-01

    Inhibition of apoptosis leads to activation of cell survival factors (e.g., AKT) causes continuous cell proliferation in cancer. Apoptosis, the major form of cellular suicide, is central to various physiological processes and the maintenance of homeostasis in multicellular organisms. A number of discoveries have clarified the molecular mechanism of apoptosis, thus clarifying the link between apoptosis and cell survival factors, which has a therapeutic outcome. Induction of apoptosis and inhib...

  18. Association of cancer stem cell markers genetic variants with gallbladder cancer susceptibility, prognosis, and survival.

    Science.gov (United States)

    Yadav, Anu; Gupta, Annapurna; Rastogi, Neeraj; Agrawal, Sushma; Kumar, Ashok; Kumar, Vijay; Mittal, Balraj

    2016-02-01

    Genes important to stem cell progression have been involved in the genetics and clinical outcome of cancers. We investigated germ line variants in cancer stem cell (CSC) genes to predict susceptibility and efficacy of chemoradiotherapy treatment in gallbladder cancer (GBC) patients. In this study, we assessed the effect of SNPs in CSC genes (surface markers CD44, ALCAM, EpCAM, CD133) and (molecular markers NANOG, SOX-2, LIN-28A, ALDH1A1, OCT-4) with GBC susceptibility and prognosis. Total 610 GBC patients and 250 controls were genotyped by using PCR-RFLP, ARMS-PCR, and TaqMan allelic discrimination assays. Chemotoxicity graded 2-4 in 200 patients and tumor response was recorded in 140 patients undergoing neoadjuvant chemotherapy (NACT). Differences in genotype and haplotype frequency distributions were calculated by binary logistic regression. Gene-gene interaction model was analyzed by generalized multifactor dimensionality reduction (GMDR). Overall survival was assessed by Kaplan-Meier survival curve and multivariate Cox-proportional methods. ALCAM Ars1157Crs10511244 (P = 0.0035) haplotype was significantly associated with GBC susceptibility. In GMDR analysis, ALCAM rs1157G>A, EpCAM rs1126497T>C emerged as best significant interaction model with GBC susceptibility and ALDH1A1 rs13959T>G with increased risk of grade 3-4 hematological toxicity. SOX-2 rs11915160A>C, OCT-4 rs3130932T>G, and NANOG rs11055786T>C were found best gene-gene interaction model for predicting response to NACT. In both Cox-proportional and recursive partitioning ALCAM rs1157GA+AA genotype showed higher mortality and hazard ratio. ALCAM gene polymorphisms associated with GBC susceptibility and survival while OCT-4, SOX-2, and NANOG variants showed an interactive role with treatment response. PMID:26318430

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

    Directory of Open Access Journals (Sweden)

    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

  20. Antigen uptake, processing and presentation to T-cells is still functional in dendritic cells surviving photodynamic treatment

    International Nuclear Information System (INIS)

    Full text: The effect of photodynamic therapy (PDT) on anti-tumoral immune reactions is still discussed controversially. Several studies have demonstrated that PDT is able to activate immune reactions against tumor antigens. However, there is also evidence that PDT exerts immunosuppressive effects. Dendritic cells (DC) are professional antigen presenting cells and play an important role in, both, the induction of immune reactions as well as the induction and maintenance of immunologic tolerance. Therefore, we investigated the effect of hypericin-mediated PDT on the capability of bone marrow-derived DC for antigen uptake, processing and presentation to CD4+ T lymphocytes. Using beta-galactosidase as model antigens we found that, under sublethal PDT conditions, antigen is still incorporated and degraded by surviving DC. PDT-treated DC, in the presence of beta-galactosidase, were still able to re-activate splenic T cells from immunized but not from naive mice. Similarly, naive allogenic T cells were activated in an antigen-independent manner by PDT-treated DC, albeit at lower efficiency as compared to untreated DC. Based on these data, we hypothesize that DC localized in PDT-treated tumor lesions could play a role in the regulation of anti-tumor immune reactions. (author)

  1. 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

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

    International Nuclear Information System (INIS)

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

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

    NARCIS (Netherlands)

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

    2004-01-01

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

  4. Hemolin triggers cell survival on fibroblasts in response to serum deprivation by inhibition of apoptosis.

    Science.gov (United States)

    Bosch, Rosemary Viola; Alvarez-Flores, Miryam Paola; Maria, Durvanei Augusto; Chudzinski-Tavassi, Ana Marisa

    2016-08-01

    Fibroblasts are the main cellular component of connective tissues and play important roles in health and disease through the production of collagen, fibronectin and growth factors. Under certain conditions, such as wound healing, fibroblasts intensify their metabolic demand, while the restriction of nutrients affect matrix composition, cell metabolism and behavior. In lepidopterans, wound healing is regulated by ecdysteroid hormones, which upregulate multifunctional proteins such as hemolin. However, the role of hemolin in cell proliferation and wound healing is not clear. rLosac is a recombinant hemolin from the caterpillar Lonomia obliqua whose proliferative and cytoprotective effects on endothelial cells have been described. Here, we show that rLosac induces a marked cell survival effect on fibroblast submitted to serum deprivation, which is observable as early as 24h, as demonstrated through the MTT assay, as well as an increase in migration of human dermal fibroblasts (HDF). No effects on cell proliferation or cell cycle distribution of fibroblasts in normal conditions were observed, suggesting that rLosac induces an effect in stressful conditions such serum deprivation but not when nutrient are sufficient. By flow cytometry, rLosac caused an apparent dose-dependent increase in cells in the S phase of the cell cycle and a significant reduction of cells with fragmented DNA. Furthermore, treatment with rLosac results in a significant decrease in the production of reactive oxygen species and in the loss of mitochondrial membrane potential, indicating that a reduction in oxidative stress is involved in rLosac-mediated cytoprotection. Our results also show an up-regulation of Bcl-2 and a down-regulation of Bax protein levels, inhibition of cytochrome c release and a reduction in caspase-3 levels, all considered critical factors for apoptosis. Moreover, rLosac treatment reduces the morphological changes induced by prolonged serum deprivation including the emergence

  5. Endothelial cell-initiated signaling promotes the survival and self-renewal of cancer stem cells

    OpenAIRE

    Krishnamurthy, Sudha; Dong, Zhihong; Vodopyanov, Dmitry; Imai, Atsushi; Helman, Joseph I.; Prince, Mark E.; Wicha, Max S.; Jacques E Nör

    2010-01-01

    Recent studies have demonstrated that cancer stem cells play an important role in the pathobiology of head and neck squamous cell carcinomas (HNSCC). However, little is known about functional interactions between head and neck cancer stem-like cells (CSC) and surrounding stromal cells. Here, we used Aldehyde Dehydrogenase activity and CD44 expression to sort putative stem cells from primary human HNSCC. Implantation of 1,000 CSC (ALDH+CD44+Lin−) led to tumors in 13 (out of 15) mice, while 10,...

  6. 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.

  7. Haematopoietic stem cell survival and transplantation efficacy is limited by the BH3-only proteins Bim and Bmf

    Science.gov (United States)

    Labi, Verena; Bertele, Daniela; Woess, Claudia; Tischner, Denise; Bock, Florian J; Schwemmers, Sven; Pahl, Heike L; Geley, Stephan; Kunze, Mirjam; Niemeyer, Charlotte M; Villunger, Andreas; Erlacher, Miriam

    2013-01-01

    Anti-apoptotic Bcl-2 family members are critical for the regulation of haematopoietic stem and progenitor cell (HSPC) survival. Little is known about the role of their pro-apoptotic antagonists, i.e. ‘BH3-only’ proteins, in this cell compartment. Based on the analysis of cytokine deprivation-induced changes in mRNA expression levels of Bcl-2 family proteins, we determined the consequences of BH3-only protein depletion on HSPC survival in culture and, for selected candidates, on engraftment in vivo. Thereby, we revealed a critical role for Bim and Bmf as regulators of HSPC dynamics both during early engraftment and long-term reconstitution. HSPCs derived from wild-type donors were readily displaced by Bim- or Bmf-deficient or Bcl-2-overexpressing HSPCs as early as 10 days after engraftment. Moreover, in the absence of Bim, significantly lower numbers of transplanted HSPCs were able to fully engraft radio-depleted recipients. Finally, we provide proof of principle that RNAi-based reduction of BIM or BMF, or overexpression of BCL-2 in human CD34+ cord blood cells may be an attractive therapeutic option to increase stem cell survival and transplantation efficacy. PMID:23180554

  8. Lentivirus mediated HO-1 gene transfer enhances myogenic precursor cell survival after autologous transplantation in pig.

    Science.gov (United States)

    Laumonier, Thomas; Yang, Sheng; Konig, Stephane; Chauveau, Christine; Anegon, Ignacio; Hoffmeyer, Pierre; Menetrey, Jacques

    2008-02-01

    Cell therapy for Duchenne muscular dystrophy and other muscle diseases is limited by a massive early cell death following injections. In this study, we explored the potential benefit of heme oxygenase-1 (HO-1) expression in the survival of porcine myogenic precursor cells (MPCs) transplanted in pig skeletal muscle. Increased HO-1 expression was assessed either by transient hyperthermia or by HO-1 lentiviral infection. One day after the thermic shock, we observed a fourfold and a threefold increase in HSP70/72 and HO-1 levels, respectively. This treatment protected 30% of cells from staurosporine-induced apoptosis in vitro. When porcine MPC were heat-shocked prior to grafting, we improved cell survival by threefold at 5 days after autologous transplantation (26.3 +/- 5.5% surviving cells). After HO-1 lentiviral transduction, almost 60% of cells expressed the transgene and kept their myogenic properties to proliferate and fuse in vitro. Apoptosis of HO-1 transduced cells was reduced by 50% in vitro after staurosporine induction. Finally, a fivefold enhancement in cell survival was observed after transplantation of HO-1-group (47.5 +/- 9.1% surviving cells) as compared to the nls-LacZ-group or control group. These results identify HO-1 as a protective gene against early MPC death post-transplantation. PMID:18026170

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

  11. Endometrial seedlings. A survival instinct? Immunomodulation and its role in the pathophysiology of endometriosis.

    Science.gov (United States)

    Portelli, M; Pollacco, J; Sacco, K; Schembri-Wismayer, P; Calleja-Agius, J

    2011-12-01

    Endometriosis occurs when ectopic cells from the endometrium implant within the peritoneum. It is considered as a disease of multifactorial aetiology and affects 7-10% of women of reproductive age worldwide. In endometriosis, the immune system is thought to be dysfunctional and various studies have shown cytokine imbalance. Commonly upregulated cytokines include Tumour necrosis factor-alpha, interferon gamma and interleukin-10. Through analysis of the molecular makeup of the peritoneal fluid, a change is shown to occur, conferring resistance from macrophages and lymphocytes to endometrial cells. This is possibly due to a reduced Inter-cellular adhesion molecule-1 synthesis. Survival of ectopic endometrial cells also arises through the expression of human leukocyte antigens. Apart from the survival of ectopic/eutopic cells in endometriosis, there is marked cellular proliferation, which has also been attributed to a change in the expression of proteins such as Bcl-2-Associated X protein, B-cell lymphoma-2 protein, transforming growth factor-beta and the enzyme aromatase. Danazol and aromatase inhibitors modulate the immune system, thus allowing partial restoration of cytokine levels. Pharmacogenomics may be the way forward in developing novel treatment modalities for endometriosis. PMID:22036759

  12. 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.

  13. Pancreatic Satellite Cells Derived Galectin-1 Increase the Progression and Less Survival of Pancreatic Ductal Adenocarcinoma

    Science.gov (United States)

    Gao, Jun; Wang, Sen; Ye, Nianyuan; Li, Ping; Gao, Sujun; Miao, Yi; Wang, Daorong; Jiang, Kuirong

    2014-01-01

    Background Galectin-1, a member of carbohydrate-binding proteins with a polyvalent function on tumor progression, was found strongly expressed in pancreatic satellite cells (PSCs), which partner in crime with cancer cells and promote the development of pancreatic ductal adenocarcinoma (PDAC). We evaluated the effects of PSCs derived Galectin-1 on the progression of PDAC, as well as the tumor establishment and development in mouse xenografts. Methods The relationship between immunohistochemistry staining intensity of Galectin-1 and clinicopathologic variables were assessed in 66 PDAC tissues, 18 chronic pancreatitis tissues and 10 normal controls. The roles of PSCs isolated from PDAC and normal pancreas on the proliferative activity, MMP2 and MMP9 expression, and the invasion of CFPAC-1 in the co-cultured system, as well as on the tumor establishment and development in mouse xenografts by mixed implanting with CFPAC-1 subcutaneously were evaluated. Results Galectin-1 expression was gradually increased from normal pancreas (negative), chronic pancreatitis (weak) to PDAC (strong), in which Galectin-1 expression was also increased from well, moderately to poorly differentiated PDAC. Galectin-1 staining intensity of pancreatic cancer tissue was associated with increase in tumor size, lymph node metastasis, perineural invasion and differentiation and UICC stage, and served as the independent prognostic indicator of poor survival of pancreatic cancer. In vitro and in vivo experiments indicated that TGF-β1 upregulated Galectin-1 expression in PSCs, which could further promotes the proliferative activity, MMP2 and MMP9 expression, and invasion of pancreatic cancer cells, as well as the tumor establishment and growth. Conclusion Galectin-1 expression in stromal cells of pancreatic cancer suggests that this protein plays a role in the promotion of cancer cells invasion and metastasis and provides a therapeutic target for the treatment of pancreatic cancer. PMID:24595374

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

    NARCIS (Netherlands)

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

    2010-01-01

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

  15. Piperlongumine inhibits the proliferation and survival of B-cell acute lymphoblastic leukemia cell lines irrespective of glucocorticoid resistance.

    Science.gov (United States)

    Han, Seong-Su; Han, Sangwoo; Kamberos, Natalie L

    2014-09-26

    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. PMID:25193702

  16. Cell Survival and Apoptosis Signaling as Therapeutic Target for Cancer: Marine Bioactive Compounds

    Directory of Open Access Journals (Sweden)

    Kim Se-Kwon

    2013-01-01

    Full Text Available Inhibition of apoptosis leads to activation of cell survival factors (e.g., AKT causes continuous cell proliferation in cancer. Apoptosis, the major form of cellular suicide, is central to various physiological processes and the maintenance of homeostasis in multicellular organisms. A number of discoveries have clarified the molecular mechanism of apoptosis, thus clarifying the link between apoptosis and cell survival factors, which has a therapeutic outcome. Induction of apoptosis and inhibition of cell survival by anticancer agents has been shown to correlate with tumor response. Cellular damage induces growth arrest and tumor suppression by inducing apoptosis, necrosis and senescence; the mechanism of cell death depends on the magnitude of DNA damage following exposure to various anticancer agents. Apoptosis is mainly regulated by cell survival and proliferating signaling molecules. As a new therapeutic strategy, alternative types of cell death might be exploited to control and eradicate cancer cells. This review discusses the signaling of apoptosis and cell survival, as well as the potential contribution of marine bioactive compounds, suggesting that new therapeutic strategies might follow.

  17. Switching roles: the functional plasticity of adult tissue stem cells.

    Science.gov (United States)

    Wabik, Agnieszka; Jones, Philip H

    2015-05-01

    Adult organisms have to adapt to survive, and the same is true for their tissues. Rates and types of cell production must be rapidly and reversibly adjusted to meet tissue demands in response to both local and systemic challenges. Recent work reveals how stem cell (SC) populations meet these requirements by switching between functional states tuned to homoeostasis or regeneration. This plasticity extends to differentiating cells, which are capable of reverting to SCs after injury. The concept of the niche, the micro-environment that sustains and regulates stem cells, is broadening, with a new appreciation of the role of physical factors and hormonal signals. Here, we review different functions of SCs, the cellular mechanisms that underlie them and the signals that bias the fate of SCs as they switch between roles. PMID:25812989

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

    OpenAIRE

    Ligthart, Sjoerd T.; Frank A W Coumans; Gerhardt Attard; Amy Mulick Cassidy; de Bono, Johann S.; Terstappen, Leon 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 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 t...

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

    OpenAIRE

    Buch Karl; Peters Tanja; Nawroth Thomas; Sänger Markus; Schmidberger Heinz; Langguth Peter

    2012-01-01

    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 calc...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-03-15

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

  1. A novel in vitro survival assay of small intestinal stem cells after exposure to ionizing radiation

    International Nuclear Information System (INIS)

    The microcolony assay developed by Withers and Elkind has been a gold standard to assess the surviving fraction of small intestinal stem cells after exposure to high (≥8 Gy) doses of ionizing radiation (IR), but is not applicable in cases of exposure to lower doses. Here, we developed a novel in vitro assay that enables assessment of the surviving fraction of small intestinal stem cells after exposure to lower IR doses. The assay includes in vitro culture of small intestinal stem cells, which allows the stem cells to develop into epithelial organoids containing all four differentiated cell types of the small intestine. We used Lgr5-EGFP-IRES-CreERT2/ROSA26-tdTomato mice to identify Lgr5+ stem cells and their progeny. Enzymatically dissociated single crypt cells from the duodenum and jejunum of mice were irradiated with 7.25, 29, 101, 304, 1000, 2000 and 4000 mGy of X-rays immediately after plating, and the number of organoids was counted on Day 12. Organoid-forming efficiency of irradiated cells relative to that of unirradiated controls was defined as the surviving fraction of stem cells. We observed a significant decrease in the surviving fraction of stem cells at ≥1000 mGy. Moreover, fluorescence-activated cell sorting analyses and passage of the organoids revealed that proliferation of stem cells surviving IR is significantly potentiated. Together, the present study demonstrates that the in vitro assay is useful for quantitatively assessing the surviving fraction of small intestinal stem cells after exposure to lower doses of IR as compared with previous examinations using the microcolony assay. (author)

  2. Assessment of the tumourigenic and metastatic properties of SK-MEL28 melanoma cells surviving electrochemotherapy with bleomycin

    International Nuclear Information System (INIS)

    Electrochemotherapy is a local treatment combining chemotherapy and electroporation and is highly effective treatment approach for subcutaneous tumours of various histologies. Contrary to surgery and radiation, the effect of electrochemotherapy on metastatic potential of tumour cells has not been extensively studied. The aim of the study was to evaluate the effect of electrochemotherapy with bleomycin on the metastatic potential of human melanoma cells in vitro. Viable cells 48 hours after electrochemotherapy were tested for their ability to migrate and invade through Matrigel coated porous membrane. In addition, microarray analysis and quantitative Real-Time PCR were used to detect changes in gene expression after electrochemotherapy. Cell migration and invasion were not changed in melanoma cells surviving electrochemotherapy. Interestingly, only a low number of tumourigenesis related genes was differentially expressed after electrochemotherapy. Our data suggest that metastatic potential of human melanoma cells is not affected by electrochemotherapy with bleomycin, confirming safe role of electrochemotherapy in the clinics

  3. Glucose-independent glutamine metabolism via TCA cycling for proliferation and survival in B-cells

    Science.gov (United States)

    Le, Anne; Lane, Andrew N.; Hamaker, Max; Bose, Sminu; Gouw, Arvin; Barbi, Joseph; Tsukamoto, Takashi; Rojas, Camilio J.; Slusher, Barbara S.; Zhang, Haixia; Zimmerman, Lisa J.; Liebler, Daniel C.; Slebos, Robbert J.C.; Lorkiewicz, Pawel K.; Higashi, Richard M.; Fan, Teresa W. M.; Dang, Chi V.

    2012-01-01

    Summary Because MYC plays a causal role in many human cancers, including those with hypoxic and nutrient-poor tumor microenvironments, we have determined the metabolic responses of a MYC-inducible human Burkitt lymphoma model P493 cell line to aerobic and hypoxic conditions, and to glucose deprivation, using Stable Isotope Resolved Metabolomics. Using [U-13C]-glucose as the tracer, both glucose consumption and lactate production were increased by MYC expression and hypoxia. Using [U-13C,15N]-glutamine as the tracer, glutamine import and metabolism through the TCA cycle persisted under hypoxia, and glutamine contributed significantly to citrate carbons. Under glucose deprivation, glutamine-derived fumarate, malate, and citrate were significantly increased. Their 13C labeling patterns demonstrate an alternative energy-generating glutaminolysis pathway involving a glucose-independent TCA cycle. The essential role of glutamine metabolism in cell survival and proliferation under hypoxia and glucose deficiency, makes them susceptible to the glutaminase inhibitor BPTES, and hence could be targeted for cancer therapy. PMID:22225880

  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. PMID:26801201

  5. Peroxidation due to cryoprotectant treatment is a vital factor for cell survival in Arabidopsis cryopreservation.

    Science.gov (United States)

    Ren, Li; Zhang, Di; Jiang, Xiang-Ning; Gai, Ying; Wang, Wei-Ming; Reed, Barbara M; Shen, Xiao-Hui

    2013-11-01

    Cryopreservation can be a safe and cost-effective tool for the long-term storage of plant germplasm. In Arabidopsis, the ability to recover from cryogenic treatment was lost as growth progressed. Growth could be restored in 48-h seedlings, whereas 72-h seedlings died after cryogenic treatment. Why seedling age and survival are negatively correlated is an interesting issue. A comparative transcriptomics was performed to screen differentially expressed genes between 48- and 72-h seedlings after exposure to cryoprotectant. Among differentially expressed genes, oxidative stress response genes played important roles in cryoprotectant treatment, and peroxidation was a key factor related to cell survival. Seedlings underwent more peroxidation at 72-h than at 48-h. A comprehensive analysis indicated that peroxidation injured membrane systems leading to photophosphorylation and oxidative phosphorylation damage. Furthermore, the apoptosis-like events were found in cryogenic treatment of Arabidopsis seedlings. 48- and 72-h seedlings underwent different degrees of membrane lipid peroxidation during cryoprotectant treatment, and reducing the injury of oxidative stress was an important factor to successful cryopreservation. This study provided a novel insight of genetic regulatory mechanisms in cryopreservation, and established an excellent model to test and evaluate the effect of exogenous antioxidants and conventional cryoprotectants in plant cryopreservation. PMID:24094052

  6. The radiosensitivity of a murine fibrosarcoma as measured by three cell survival assays.

    Science.gov (United States)

    Rice, L; Urano, M; Suit, H D

    1980-04-01

    The radiation sensitivity of a weakly immunogenic spontaneous fibrosarcoma of the C3Hf/Sed mouse (designated FSa-II) was assessed by three in vivo cell survival methods: end-point dilution (TD50) assay, lung colony (LC) assay, and agar diffusion chamber (ADC) assay. The hypoxic fraction of this tumour was also determined by the ADC method. Although there was a good agreement of the cell survival data between the ADC and LC methods, the TD50 method yielded a considerably less steep cell survival curve. Beneficial aspects and limitations of each assay are discussed. In addition, the use of the ADC method for the growth of xenogeneic cell lines and a preliminary experiment with human tumour cells in non-immunosuppressed hosts suggest that this method may be a valuable adjunct for studying the growth and therapeutic responses of human tumour cells. PMID:6932931

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

    International Nuclear Information System (INIS)

    Results of experiments with V79 cells growing in tissue culture indicate that the reproductive survival of cells following irradiation is influenced by the level of intracellular 3', 5'-cyclic adenosine monophosphate (cyclic AMP) at the time of irradiation. Cells containing high levels of cyclic AMP induced by treatments with drugs show a characteristic survival curve in which the extent of the shoulder is increased so that the survival after low doses is enhanced. The exponential slope or D0, however, is decreased so that at high doses the survival of cells containing high levels of cyclic AMP may be less than that of controls. Naturally occurring changes in radiosensitivity such as those observed as cells pass through the division cycle, may also be related to parallel changes in cyclic AMP concentration occurring during the cycle. Injection of mice with compounds producing elevated cyclic AMP prior to whole-body irradiation increases survival at seven days post-irradiation. The shape of the survival curve for intestinal stem cells in these mice differs from that of the control in having an increased extrapolation number; no change in D0 is observed in this in vivo situation. (author)

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

    International Nuclear Information System (INIS)

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

  9. NF-κB2 mutation targets survival, proliferation and differentiation pathways in the pathogenesis of plasma cell tumors

    Directory of Open Access Journals (Sweden)

    McCarthy Brian A

    2012-05-01

    Full Text Available Abstract Background Abnormal NF-κB2 activation has been implicated in the pathogenesis of multiple myeloma, a cancer of plasma cells. However, a causal role for aberrant NF-κB2 signaling in the development of plasma cell tumors has not been established. Also unclear is the molecular mechanism that drives the tumorigenic process. We investigated these questions by using a transgenic mouse model with lymphocyte-targeted expression of p80HT, a lymphoma-associated NF-κB2 mutant, and human multiple myeloma cell lines. Methods We conducted a detailed histopathological characterization of lymphomas developed in p80HT transgenic mice and microarray gene expression profiling of p80HT B cells with the goal of identifying genes that drive plasma cell tumor development. We further verified the significance of our findings in human multiple myeloma cell lines. Results Approximately 40% of p80HT mice showed elevated levels of monoclonal immunoglobulin (M-protein in the serum and developed plasma cell tumors. Some of these mice displayed key features of human multiple myeloma with accumulation of plasma cells in the bone marrow, osteolytic bone lesions and/or diffuse osteoporosis. Gene expression profiling of B cells from M-protein-positive p80HT mice revealed aberrant expression of genes known to be important in the pathogenesis of multiple myeloma, including cyclin D1, cyclin D2, Blimp1, survivin, IL-10 and IL-15. In vitro assays demonstrated a critical role of Stat3, a key downstream component of IL-10 signaling, in the survival of human multiple myeloma cells. Conclusions These findings provide a mouse model for human multiple myeloma with aberrant NF-κB2 activation and suggest a molecular mechanism for NF-κB2 signaling in the pathogenesis of plasma cell tumors by coordinated regulation of plasma cell generation, proliferation and survival.

  10. NF-κB2 mutation targets survival, proliferation and differentiation pathways in the pathogenesis of plasma cell tumors

    International Nuclear Information System (INIS)

    Abnormal NF-κB2 activation has been implicated in the pathogenesis of multiple myeloma, a cancer of plasma cells. However, a causal role for aberrant NF-κB2 signaling in the development of plasma cell tumors has not been established. Also unclear is the molecular mechanism that drives the tumorigenic process. We investigated these questions by using a transgenic mouse model with lymphocyte-targeted expression of p80HT, a lymphoma-associated NF-κB2 mutant, and human multiple myeloma cell lines. We conducted a detailed histopathological characterization of lymphomas developed in p80HT transgenic mice and microarray gene expression profiling of p80HT B cells with the goal of identifying genes that drive plasma cell tumor development. We further verified the significance of our findings in human multiple myeloma cell lines. Approximately 40% of p80HT mice showed elevated levels of monoclonal immunoglobulin (M-protein) in the serum and developed plasma cell tumors. Some of these mice displayed key features of human multiple myeloma with accumulation of plasma cells in the bone marrow, osteolytic bone lesions and/or diffuse osteoporosis. Gene expression profiling of B cells from M-protein-positive p80HT mice revealed aberrant expression of genes known to be important in the pathogenesis of multiple myeloma, including cyclin D1, cyclin D2, Blimp1, survivin, IL-10 and IL-15. In vitro assays demonstrated a critical role of Stat3, a key downstream component of IL-10 signaling, in the survival of human multiple myeloma cells. These findings provide a mouse model for human multiple myeloma with aberrant NF-κB2 activation and suggest a molecular mechanism for NF-κB2 signaling in the pathogenesis of plasma cell tumors by coordinated regulation of plasma cell generation, proliferation and survival

  11. Cytokine profile of conditioned medium from human tumor cell lines after acute and fractionated doses of gamma radiation and its effect on survival of bystander tumor cells.

    Science.gov (United States)

    Desai, Sejal; Kumar, Amit; Laskar, S; Pandey, B N

    2013-01-01

    Cytokines are known to play pivotal roles in cancer initiation, progression and pathogenesis. Accumulating evidences suggest differences in basal and stress-induced cytokine profiles of cancers with diverse origin. However, a comprehensive investigation characterising the cytokine profile of various tumor types after acute and fractionated doses of gamma-irradiation, and its effect on survival of bystander cells is not well known in literature. In the present study, we have evaluated the cytokine secretion profile of human tumor cell lines (HT1080, U373MG, HT29, A549 and MCF-7) either before (basal) or after acute (2, 6 Gy) and fractionated doses (3×2 Gy) of gamma-irradiation in culture medium obtained from these cells by multiplex bead array/ELISA. Moreover, clonogenic assays were performed to evaluate the effect of conditioned medium (CM) on the survival and growth of respective cells. Based on the screening of 28 analytes, our results showed that the basal profiles of these cell lines varied considerably in terms of the number and magnitude of secreted factors, which was minimum in MCF-7. Interestingly, TNF-α, IL-1β, PDGF-AA, TGF-β1, fractalkine, IL-8, VEGF and GCSF were found in CM of all the cell lines. However, secretion of certain cytokines was cell line-specific. Moreover, CM caused increase in clonogenic survival of respective tumor cells (in the order HT1080>U373MG>HT29>A549>MCF-7), which was correlated with the levels of IL-1β, IL-6, IL-8, GMCSF and VEGF in their CM. After irradiation, the levels of most of the cytokines increased markedly in a dose dependent manner. The fold change in cytokine levels was lower in irradiated conditioned medium (ICM) of tumor cells collected after fractionated than respective acute dose, except in MCF-7. Interestingly, amongst these cell lines, the radiation-induced fold increase in cytokine levels was maximum in ICM of A549 cells. Moreover, bystander A549 cells treated with respective ICM showed dose dependent

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

    Directory of Open Access Journals (Sweden)

    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

  13. Homotypic RANK signaling differentially regulates proliferation, motility and cell survival in osteosarcoma and mammary epithelial cells.

    Science.gov (United States)

    Beristain, Alexander G; Narala, Swami R; Di Grappa, Marco A; Khokha, Rama

    2012-02-15

    RANKL (receptor activator of NF-κB ligand) is a crucial cytokine for regulating diverse biological systems such as innate immunity, bone homeostasis and mammary gland differentiation, operating through activation of its cognate receptor RANK. In these normal physiological processes, RANKL signals through paracrine and/or heterotypic mechanisms where its expression and function is tightly controlled. Numerous pathologies involve RANKL deregulation, such as bone loss, inflammatory diseases and cancer, and aberrant RANK expression has been reported in bone cancer. Here, we investigated the significance of RANK in tumor cells with a particular emphasis on homotypic signaling. We selected RANK-positive mouse osteosarcoma and RANK-negative preosteoblastic MC3T3-E1 cells and subjected them to loss- and gain-of-RANK function analyses. By examining a spectrum of tumorigenic properties, we demonstrate that RANK homotypic signaling has a negligible effect on cell proliferation, but promotes cell motility and anchorage-independent growth of osteosarcoma cells and preosteoblasts. By contrast, establishment of RANK signaling in non-tumorigenic mammary epithelial NMuMG cells promotes their proliferation and anchorage-independent growth, but not motility. Furthermore, RANK activation initiates multiple signaling pathways beyond its canonical target, NF-κB. Among these, biochemical inhibition reveals that Erk1/2 is dominant and crucial for the promotion of anchorage-independent survival and invasion of osteoblastic cells, as well as the proliferation of mammary epithelial cells. Thus, RANK signaling functionally contributes to key tumorigenic properties through a cell-autonomous homotypic mechanism. These data also identify the likely inherent differences between epithelial and mesenchymal cell responsiveness to RANK activation. PMID:22421365

  14. Genetic Engineering of Mesenchymal Stem Cells to Induce Their Migration and Survival

    Science.gov (United States)

    Nowakowski, Adam; Walczak, Piotr; Lukomska, Barbara; Janowski, Miroslaw

    2016-01-01

    Mesenchymal stem cells (MSCs) are very attractive for regenerative medicine due to their relatively easy derivation and broad range of differentiation capabilities, either naturally or induced through cell engineering. However, efficient methods of delivery to diseased tissues and the long-term survival of grafted cells still need improvement. Here, we review genetic engineering approaches designed to enhance the migratory capacities of MSCs, as well as extend their survival after transplantation by the modulation of prosurvival approaches, including prevention of senescence and apoptosis. We highlight some of the latest examples that explore these pivotal points, which have great relevance in cell-based therapies.

  15. ALS/FTLD-linked TDP-43 regulates neurite morphology and cell survival in differentiated neurons

    International Nuclear Information System (INIS)

    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

  16. 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.

  17. Controlling Redox Status for Stem Cell Survival, Expansion, and Differentiation

    OpenAIRE

    Sébastien Sart; Liqing Song; Yan Li

    2015-01-01

    Reactive oxygen species (ROS) have long been considered as pathological agents inducing apoptosis under adverse culture conditions. However, recent findings have challenged this dogma and physiological levels of ROS are now considered as secondary messengers, mediating numerous cellular functions in stem cells. Stem cells represent important tools for tissue engineering, drug screening, and disease modeling. However, the safe use of stem cells for clinical applications still requires culture ...

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

    International Nuclear Information System (INIS)

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

  19. miR-8 modulates cytoskeletal regulators to influence cell survival and epithelial organization in Drosophila wings.

    Science.gov (United States)

    Bolin, Kelsey; Rachmaninoff, Nicholas; Moncada, Kea; Pula, Katharine; Kennell, Jennifer; Buttitta, Laura

    2016-04-01

    The miR-200 microRNA family plays important tumor suppressive roles. The sole Drosophila miR-200 ortholog, miR-8 plays conserved roles in Wingless, Notch and Insulin signaling - pathways linked to tumorigenesis, yet homozygous null animals are viable and often appear morphologically normal. We observed that wing tissues mosaic for miR-8 levels by genetic loss or gain of function exhibited patterns of cell death consistent with a role for miR-8 in modulating cell survival in vivo. Here we show that miR-8 levels impact several actin cytoskeletal regulators that can affect cell survival and epithelial organization. We show that loss of miR-8 can confer resistance to apoptosis independent of an epithelial to mesenchymal transition while the persistence of cells expressing high levels of miR-8 in the wing epithelium leads to increased JNK signaling, aberrant expression of extracellular matrix remodeling proteins and disruption of proper wing epithelial organization. Altogether our results suggest that very low as well as very high levels of miR-8 can contribute to hallmarks associated with cancer, suggesting approaches to increase miR-200 microRNAs in cancer treatment should be moderate. PMID:26902111

  20. Conditioning the cochlea to facilitate survival and integration of exogenous cells into the auditory epithelium.

    Science.gov (United States)

    Park, Yong-Ho; Wilson, Kevin F; Ueda, Yoshihisa; Tung Wong, Hiu; Beyer, Lisa A; Swiderski, Donald L; Dolan, David F; Raphael, Yehoash

    2014-04-01

    The mammalian auditory epithelium (AE) cannot replace supporting cells and hair cells once they are lost. Therefore, sensorineural hearing loss associated with missing cells is permanent. This inability to regenerate critical cell types makes the AE a potential target for cell replacement therapies such as stem cell transplantation. Inserting stem cells into the AE of deaf ears is a complicated task due to the hostile, high potassium environment of the scala media in the cochlea, and the robust junctional complexes between cells in the AE that resist stem cell integration. Here, we evaluate whether temporarily reducing potassium levels in the scala media and disrupting the junctions in the AE make the cochlear environment more receptive and facilitate survival and integration of transplanted cells. We used sodium caprate to transiently disrupt the AE junctions, replaced endolymph with perilymph, and blocked stria vascularis pumps with furosemide. We determined that these three steps facilitated survival of HeLa cells in the scala media for at least 7 days and that some of the implanted cells formed a junctional contact with native AE cells. The data suggest that manipulation of the cochlear environment facilitates survival and integration of exogenously transplanted HeLa cells in the scala media. PMID:24394296

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

    International Nuclear Information System (INIS)

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

  2. Urokinase mediates endothelial cell survival via induction of the X-linked inhibitor of apoptosis protein

    DEFF Research Database (Denmark)

    Prager, Gerald W; Mihaly, Judit; Brunner, Patrick M;

    2008-01-01

    factor kappaB (NF-kappaB) p52 activation. Indeed, blocking NF-kappaB activation by using specific NF-kappaB inhibitors abolished uPA-induced cell survival as it blocked uPA-induced XIAP up-regulation. Furthermore, down-regulating XIAP expression by small interfering RNA (siRNA) significantly reduced u......Urokinase-type plasminogen activator (uPA) additionally elicits a whole array of pro-angiogenic responses, such as differentiation, proliferation, and migration. In this study, we demonstrate that in endothelial cells uPA also protects against apoptosis by transcriptional up-regulation and......PA-dependent endothelial cell survival. This mechanism is also important for VEGF-induced antiapoptosis because VEGF-dependent up-regulation of XIAP was found defective in uPA(-/-) endothelial cells. This led us to conclude that uPA is part of a novel NF-kappaB-dependent cell survival pathway....

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

    International Nuclear Information System (INIS)

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

  4. XIAP is not required for human tumor cell survival in the absence of an exogenous death signal

    International Nuclear Information System (INIS)

    The X-linked Inhibitor of Apoptosis (XIAP) has attracted much attention as a cancer drug target. It is the only member of the IAP family that can directly inhibit caspase activity in vitro, and it can regulate apoptosis and other biological processes through its C-terminal E3 ubiquitin ligase RING domain. However, there is controversy regarding XIAP's role in regulating tumor cell proliferation and survival under normal growth conditions in vitro. We utilized siRNA to systematically knock down XIAP in ten human tumor cell lines and then monitored both XIAP protein levels and cell viability over time. To examine the role of XIAP in the intrinsic versus extrinsic cell death pathways, we compared the viability of XIAP depleted cells treated either with a variety of mechanistically distinct, intrinsic pathway inducing agents, or the canonical inducer of the extrinsic pathway, TNF-related apoptosis-inducing ligand (TRAIL). XIAP knockdown had no effect on the viability of six cell lines, whereas the effect in the other four was modest and transient. XIAP knockdown only sensitized tumor cells to TRAIL and not the mitochondrial pathway inducing agents. These data indicate that XIAP has a more central role in regulating death receptor mediated apoptosis than it does the intrinsic pathway mediated cell death

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

    International Nuclear Information System (INIS)

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

  6. 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

  7. Bcl-xL-Mediated Changes in Metabolic Pathways of Breast Cancer Cells : From Survival in the Blood Stream to Organ-Specific Metastasis

    OpenAIRE

    España, Laura; Martín, Berta; Aragüés, Ramón; Chiva, Cristina; Oliva, Baldo; Andreu, David; Sierra, Angels

    2005-01-01

    Bcl-xL protein plays a role in breast cancer dormancy, promoting survival of cells in metastatic foci by counteracting the proapoptotic signals in the microenvironment. The aim of this study was to identify phenotypes mediated by Bcl-xL in breast cancer cells that enhance in vivo survival of clinical metastases. 435/Bcl-xL or 435/Neo human breast cancer cells were injected into the inguinal mammary gland of nude mice, and tumors, metastases in lymph node, lung, and bone, and bloodstream survi...

  8. A distinct subset of self-renewing human memory CD8+ T cells survives cytotoxic chemotherapy

    OpenAIRE

    Turtle, Cameron J.; Swanson, Hillary M.; Fujii, Nobuharu; Estey, Elihu H.; Riddell, Stanley R.

    2009-01-01

    The mechanisms that maintain human T cell memory during normal and perturbed homeostasis are not fully understood. The repeated induction of profound lymphocytopenia in patients undergoing multiple cycles of cytotoxic chemotherapy infrequently results in severe infections with viruses controlled by memory T cells, suggesting that some memory T cells survive chemotherapy and restore immunity. Here we identify a distinct subpopulation of memory CD8+ T cells with the ability to rapidly efflux an...

  9. Dormancy of Cancer Cells with Suppression of AKT Activity Contributes to Survival in Chronic Hypoxia

    OpenAIRE

    Hiroko Endo; Hiroaki Okuyama; Masayuki Ohue; Masahiro Inoue

    2014-01-01

    A hypoxic microenvironment in tumors has been recognized as a cause of malignancy or resistance to various cancer therapies. In contrast to recent progress in understanding the acute response of cancer cells to hypoxia, the characteristics of tumor cells in chronic hypoxia remain elusive. We have identified a pancreatic cancer cell line, AsPC-1, that is exceptionally able to survive for weeks under 1% oxygen conditions while most tested cancer cell lines die after only some days under these c...

  10. CXCR2 and CXCL4 regulate survival and self-renewal of hematopoietic stem/progenitor cells.

    Science.gov (United States)

    Sinclair, Amy; Park, Laura; Shah, Mansi; Drotar, Mark; Calaminus, Simon; Hopcroft, Lisa E M; Kinstrie, Ross; Guitart, Amelie V; Dunn, Karen; Abraham, Sheela A; Sansom, Owen; Michie, Alison M; Machesky, Laura; Kranc, Kamil R; Graham, Gerard J; Pellicano, Francesca; Holyoake, Tessa L

    2016-07-21

    The regulation of hematopoietic stem cell (HSC) survival and self-renewal within the bone marrow (BM) niche is not well understood. We therefore investigated global transcriptomic profiling of normal human HSC/hematopoietic progenitor cells [HPCs], revealing that several chemokine ligands (CXCL1-4, CXCL6, CXCL10, CXCL11, and CXCL13) were upregulated in human quiescent CD34(+)Hoescht(-)Pyronin Y(-) and primitive CD34(+)38(-), as compared with proliferating CD34(+)Hoechst(+)Pyronin Y(+) and CD34(+)38(+) stem/progenitor cells. This suggested that chemokines might play an important role in the homeostasis of HSCs. In human CD34(+) hematopoietic cells, knockdown of CXCL4 or pharmacologic inhibition of the chemokine receptor CXCR2, significantly decreased cell viability and colony forming cell (CFC) potential. Studies on Cxcr2(-/-) mice demonstrated enhanced BM and spleen cellularity, with significantly increased numbers of HSCs, hematopoietic progenitor cell-1 (HPC-1), HPC-2, and Lin(-)Sca-1(+)c-Kit(+) subpopulations. Cxcr2(-/-) stem/progenitor cells showed reduced self-renewal capacity as measured in serial transplantation assays. Parallel studies on Cxcl4 demonstrated reduced numbers of CFC in primary and secondary assays following knockdown in murine c-Kit(+) cells, and Cxcl4(-/-) mice showed a decrease in HSC and reduced self-renewal capacity after secondary transplantation. These data demonstrate that the CXCR2 network and CXCL4 play a role in the maintenance of normal HSC/HPC cell fates, including survival and self-renewal. PMID:27222476

  11. The shape of radiation survival curves of mammalian cells cultured in vitro

    International Nuclear Information System (INIS)

    Various in vivo and in vitro techniques to study the survival of single mammalian cells are now well known. The potential applications of formal data obtained by these methods to problems of human exposure, radiotherapy, radiation protection and the like are extensive. Mammalian cell techniques, particularly in vitro, have also extended greatly the opportunity to study basic interactions between radiation and processes occurring in cells at the time of exposure. In survival curve analysis and interpretation and the dependence of survival upon different types of radiation, formerly confined chiefly to microorganisms, single mammalian cell studies open new avenues. These cells are large, sensitive to radiation, and cytologically relatively well known. Although it would be rash to suggest that more is known about them than some microorganisms, at least some details of structure, chromosome morphology, and the pattern and order of DNA synthesis are quite well established. The prospects of quantitatively relating changes in structure and behaviour to radiation exposure in the form of some coherent model therefore seem enhanced. This paper discusses survival data for mammalian cells cultured in vitro from three points of view: first, technical or experimental factors which can vary the shape of the survival curve; second, the effect of heterogeneity among individuals of the populations generally studied; third, mathematical expressions or models other than which may fit the observed data better

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

    OpenAIRE

    Razmik Mirzayans; Bonnie Andrais; Piyush Kumar; David Murray

    2016-01-01

    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 t...

  13. 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.

  14. Piperlongumine inhibits the proliferation and survival of B-cell acute lymphoblastic leukemia cell lines irrespective of glucocorticoid resistance

    International Nuclear Information System (INIS)

    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. SV40 DNA amplification and reintegration in surviving hamster cells after 60Co γ-irradiation

    International Nuclear Information System (INIS)

    SV40-transformed Chinese hamster embryo cells were exposed to 60Co γ-irradiation and the fate of the integrated SV40 sequences was pursued over a period of 20 days following radiation exposure. As shown by colony hybridization, integrated SV40 sequences were amplified in surviving and non-surviving cells. At later times, however, clonal sublines of surviving cells grown for 20-30 cell generations after irradiation had lost most of their amplified SV40 copies but showed altered restriction fragment patterns indicating reintegration of SV40 sequences at new sites of the hamster genome. This suggest that 60Co γ-irradiation can generate mutations by inducing over-replication of chromosome segments that are then substrates of enzymatic rearrangements. (author)

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

    International Nuclear Information System (INIS)

    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

  17. 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.

  18. Imprinted survival genes preclude loss of heterozygosity of chromosome 7 in cancer cells.

    Science.gov (United States)

    Boot, Arnoud; Oosting, Jan; de Miranda, Noel Fcc; Zhang, Yinghui; Corver, Willem E; van de Water, Bob; Morreau, Hans; van Wezel, Tom

    2016-09-01

    The genomes of a wide range of cancers, including colon, breast, and thyroid cancers, frequently show copy number gains of chromosome 7 and rarely show loss of heterozygosity. The molecular basis for this phenomenon is unknown. Strikingly, oncocytic follicular thyroid carcinomas can display an extreme genomic profile, with homozygosity of all chromosomes except for chromosome 7. The observation that homozygosity of chromosome 7 is never observed suggests that retention of heterozygosity is essential for cells. We hypothesized that cell survival genes are genetically imprinted on either of two copies of chromosome 7, which thwarts loss of heterozygosity at this chromosome in cancer cells. By employing a DNA methylation screen and gene expression analysis, we identified six imprinted genes that force retention of heterozygosity on chromosome 7. Subsequent knockdown of gene expression showed that CALCR, COPG2, GRB10, KLF14, MEST, and PEG10 were essential for cancer cell survival, resulting in reduced cell proliferation, G1 -phase arrest, and increased apoptosis. We propose that imprinted cell survival genes provide a genetic basis for retention of chromosome 7 heterozygosity in cancer cells. The monoallelically expressed cell survival genes identified in this study, and the cellular pathways that they are involved in, offer new therapeutic targets for the treatment of tumours showing retention of heterozygosity on chromosome 7. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:27265324

  19. 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...

  20. Persistence of disseminated tumor cells after neoadjuvant treatment for locally advanced breast cancer predicts poor survival

    OpenAIRE

    Mathiesen, Randi R.; Borgen, Elin; Renolen, Anne; Løkkevik, Erik; Nesland, Jahn M; Anker, Gun; Østenstad, Bjørn; Lundgren, Steinar; Risberg, Terje; Mjaaland, Ingvil; Kvalheim, Gunnar; Lønning, Per E.; Naume, Bjørn

    2012-01-01

    Introduction Presence of disseminated tumor cells (DTCs) in bone marrow (BM) and circulating tumor cells (CTC) in peripheral blood (PB) predicts reduced survival in early breast cancer. The aim of this study was to determine the presence of and alterations in DTC- and CTC-status in locally advanced breast cancer patients undergoing neoadjuvant chemotherapy (NACT) and to evaluate their prognostic impact. Methods ...

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

    International Nuclear Information System (INIS)

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

  2. Elevated expression of KIF18A enhances cell proliferation and predicts poor survival in human clear cell renal carcinoma

    Science.gov (United States)

    CHEN, QI; CAO, BIN; NAN, NING; WANG, YU; ZHAI, XU; LI, YOUFANG; CHONG, TIE

    2016-01-01

    The function of kinesin family member 18A (KIF18A) in human renal cell carcinoma (RCC) is unclear. The purpose of the current study was to determine the expression and prognostic significance of KIF18A in RCC. Specimens from 273 RCC patients undergoing nephrectomies were studied. Expression of KIF18A mRNA was examined by reverse transcription-polymerase chain reaction (RT-PCR) or quantitative PCR, and the expression of KIF18A protein was examined by immunohistochemistry and western blotting. The expression of KIF18A in clear-cell RCC cell lines was decreased using small interfering RNA targeting KIF18A, and increased by transfection with KIF18A cDNA. The proliferative ability of RCC cells in vitro and in vivo was detected by WST-1 assay and an animal xenograft model with BALB/c nude mice, respectively. The association between KIF18A expression and overall survival was calculated using Kaplan-Meier analysis. The results showed that KIF18A expression was significantly increased in RCC tissues compared with normal kidney tissues. The level of KIF18A expression was significantly associated with tumor stage, histological grade, metastasis and tumor size. Moreover, KIF18A increased the proliferation of RCC cells in vitro and in vivo. KIF18A expression was upregulated in RCC and enhanced the proliferation of RCC cells. Therefore, it appears that KIF18A plays a key role in the carcinogenesis and progression of RCC, and is a novel candidate prognostic marker for RCC patients. Furthermore, silencing KIF18A expression may serve as a new therapeutic strategy against RCC.

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-08-07

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

  5. 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

  6. 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.

  7. Role of cancer stem cells in hepatocarcinogenesis

    OpenAIRE

    Wang, Bo; Jacob, Samson T.

    2011-01-01

    There has been considerable interest in cancer stem cells (CSCs) among cancer biologists and clinicians, most likely because of their role in the heterogeneity of cancer and their potential application in cancer therapeutics. Recent studies suggest that CSCs play a key role in liver carcinogenesis. A small subpopulation of cancer cells with CSC properties has been identified and characterized from hepatocellular carcinoma (HCC) cell lines, animal models and human primary HCCs. Considering the...

  8. Cross-talk between chronic lymphocytic leukemia (CLL) tumor B cells and mesenchymal stromal cells (MSCs): implications for neoplastic cell survival.

    Science.gov (United States)

    Trimarco, Valentina; Ave, Elisa; Facco, Monica; Chiodin, Giorgia; Frezzato, Federica; Martini, Veronica; Gattazzo, Cristina; Lessi, Federica; Giorgi, Carlo Alberto; Visentin, Andrea; Castelli, Monica; Severin, Filippo; Zambello, Renato; Piazza, Francesco; Semenzato, Gianpietro; Trentin, Livio

    2015-12-01

    Leukemic cells from Chronic Lymphocytic Leukemia (CLL) patients interact with stromal cells of the surrounding microenvironment. Mesenchymal Stromal Cells (MSCs) represent the main population in CLL marrow stroma, which may play a key role for disease support and progression. In this study we evaluated whether MSCs influence in vitro CLL cell survival. MSCs were isolated from the bone marrow of 46 CLL patients and were characterized by flow cytometry analysis. Following co-culture of MSCs and leukemic B cells, we demonstrated that MSCs were able to improve leukemic B cell viability, this latter being differently dependent from the signals coming from MSCs. In addition, we found that the co-culture of MSCs with leukemic B cells induced an increased production of IL-8, CCL4, CCL11, and CXCL10 chemokines.As far as drug resistance is concerned, MSCs counteract the cytotoxic effect of Fludarabine/Cyclophosphamide administration in vivo, whereas they do not protect CLL cells from the apoptosis induced by the kinase inhibitors Bafetinib and Ibrutinib. The evidence that leukemic clones are conditioned by environmental stimuli suggest new putative targets for therapy in CLL patients. PMID:26517523

  9. The influence of tumour cell DNA content on survival in colorectal cancer: a detailed analysis.

    OpenAIRE

    Armitage, N C; Ballantyne, K. C.; Evans, D F; Clarke, P; Sheffield, J.; Hardcastle, J. D.

    1990-01-01

    We have investigated the influence of tumour cell DNA content (ploidy) on survival of 416 patients undergoing excisional surgery for colorectal cancer. Two hundred and eleven (51%) tumours had an abnormal DNA content (aneuploid or tetraploid). There was no correlation between ploidy status, sex, age and pathological stage, histological grade, tumour site, local tumour extension or assessment of curability. Patients with tumours with an abnormal DNA content had a poorer survival 68/211 (32%) t...

  10. The effect of interferon-{beta} on mouse neural progenitor cell survival and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, Marek [Neurology Department, University of Vermont College of Medicine, Burlington, VT (United States); Knight, Julia [Neuroscience Department, University of Vermont College of Medicine, Burlington, VT (United States); Tobita, Mari; Soltys, John; Panitch, Hillel [Neurology Department, University of Vermont College of Medicine, Burlington, VT (United States); Mao-Draayer, Yang, E-mail: yang.mao-draayer@vtmednet.org [Neurology Department, University of Vermont College of Medicine, Burlington, VT (United States)

    2009-10-16

    Interferon-{beta} (IFN-{beta}) is a mainstay therapy for relapse-remitting multiple sclerosis (MS). However, the direct effects of IFN-{beta} on the central nervous system (CNS) are not well understood. To determine whether IFN-{beta} has direct neuroprotective effects on CNS cells, we treated adult mouse neural progenitor cells (NPCs) in vitro with IFN-{beta} and examined the effects on proliferation, apoptosis, and differentiation. We found that mouse NPCs express high levels of IFN{alpha}/{beta} receptor (IFNAR). In response to IFN-{beta} treatment, no effect was observed on differentiation or proliferation. However, IFN-{beta} treated mouse NPCs demonstrated decreased apoptosis upon growth factor withdrawal. Pathway-specific polymerase chain reaction (PCR) arrays demonstrated that IFN-{beta} treatment upregulated the STAT 1 and 2 signaling pathway, as well as GFRA2, NOD1, Caspases 1 and 12, and TNFSF10. These results suggest that IFN-{beta} can directly affect NPC survival, possibly playing a neuroprotective role in the CNS by modulating neurotrophic factors.

  11. Effect of Tc99m Labeling on The Survival Rate of Dental Pulp Stem Cells

    Directory of Open Access Journals (Sweden)

    Jabari F

    2014-02-01

    Full Text Available Background and Aim: Human dental pulp stem cells have substantial proliferative and differentiation potential. The isolated stem cells or progenitor cells of the pulp can differentiate into odontoblasts or /and osteoblast-like cells and aid in repair as well as reconstruction of tooth structure. Several ways have been introduced for isolation and tracing of these cells. The aim of this study was to isolate mesenchymal stem cells from deciduous dental pulps as well as labeling them with Technetium (Tc99m to investigate the effect of Tc labeling on the survival rate of stem cells. Materials and Methods: In this experimental study, exfoliated deciduous teeth of 6-11 year old children without any history of systemic disease were collected. Enzymatic and non-enzymatic methods were used to expedite cell isolation and isolated cells (10000 from dental pulp were mixed with 25 millicurie of Tc for tracing purposes. Individual cell activity as well as culture medium activation was evaluated separately afterwards. Data was analyzed using ANOVA statistical test. Results: Isolated dental pulp cells formed single cell derived colonies which showed fibroblast-like growth with solo cloning morphology. Specific staining of the cells indicated them to be stem cells and confirmed their differentiation into bone and fat. Moreover, Technetium significantly decreased the activity of cells. The survival rates of the cells in the period of 1,3,6,24,48 hours were reported to be 95.5%, 85.5%, 77.4%, 68.4%, and 57.3% respectively. Conclusion: The dental pulp stem cells have a significant capacity to differentiate into bone and fat. Tracing the cells with Tc M99 will reduce their survival rate over time.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Suna, E-mail: wangs3@mail.nih.gov; Zhou, Yifu; Andreyev, Oleg; Hoyt, Robert F.; Singh, Avneesh; Hunt, Timothy; Horvath, Keith A.

    2014-04-15

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

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

    International Nuclear Information System (INIS)

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

  14. Lipoic acid enhances survival of transplanted neural stem cells by reducing transplantation-associated injury

    Directory of Open Access Journals (Sweden)

    Gao J

    2013-07-01

    Full Text Available Junling Gao,1,* Jason R Thonhoff,1,2,* Tiffany J Dunn,1 Ping Wu1 1Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA; 2Department of Neurology, The Methodist Hospital, Houston, TX, USA *These authors contributed equally to this work Abstract: The efficacy of stem cell-based therapy for neurological diseases depends highly on cell survival post-transplantation. One of the key factors affecting cell survival is the grafting procedure. The current study aims to determine whether needle insertion into intact rat spinal cords creates a hypoxic environment that is prone to lipid peroxidation damage upon reperfusion, and whether an antioxidant protects human neural stem cells (hNSCs both in vitro and post-transplantation into rat spinal cords. We show here that a single needle injection creates a hypoxic environment within the rat spinal cord that peaks at approximately 12 hours before reperfusion occurs. Lipid peroxidation damage at the transplantation site is evident by 48 hours post-needle insertion. In an in vitro model, hypoxia-reperfusion results in apoptotic death of hNSCs. Pretreatment with the antioxidant, α-lipoic acid, protects hNSCs against hypoxia-reperfusion injury and oxidative stress–mediated cell death. Increasing glutathione, but not Akt signaling, contributes to the protective effect of lipoic acid. Pretreating hNSCs with lipoic acid also increases the cell survival rate 1 month post-transplantation. Further investigation is warranted to develop improved techniques to maximize the survival of transplanted stem cells. Keywords: neural stem cell, transplantation, hypoxia-reperfusion, antioxidant, cell survival, lipoic acid

  15. Increased mitochondrial fission promotes autophagy and hepatocellular carcinoma cell survival through the ROS-modulated coordinated regulation of the NFKB and TP53 pathways.

    Science.gov (United States)

    Huang, Qichao; Zhan, Lei; Cao, Haiyan; Li, Jibin; Lyu, Yinghua; Guo, Xu; Zhang, Jing; Ji, Lele; Ren, Tingting; An, Jiaze; Liu, Bingrong; Nie, Yongzhan; Xing, Jinliang

    2016-06-01

    Mitochondrial morphology is dynamically remodeled by fusion and fission in cells, and dysregulation of this process is closely implicated in tumorigenesis. However, the mechanism by which mitochondrial dynamics influence cancer cell survival is considerably less clear, especially in hepatocellular carcinoma (HCC). In this study, we systematically investigated the alteration of mitochondrial dynamics and its functional role in the regulation of autophagy and HCC cell survival. Furthermore, the underlying molecular mechanisms and therapeutic application were explored in depth. Mitochondrial fission was frequently upregulated in HCC tissues mainly due to an elevated expression ratio of DNM1L to MFN1, which significantly contributed to poor prognosis of HCC patients. Increased mitochondrial fission by forced expression of DNM1L or knockdown of MFN1 promoted the survival of HCC cells both in vitro and in vivo mainly by facilitating autophagy and inhibiting mitochondria-dependent apoptosis. We further demonstrated that the survival-promoting role of increased mitochondrial fission was mediated via elevated ROS production and subsequent activation of AKT, which facilitated MDM2-mediated TP53 degradation, and NFKBIA- and IKK-mediated transcriptional activity of NFKB in HCC cells. Also, a crosstalk between TP53 and NFKB pathways was involved in the regulation of mitochondrial fission-mediated cell survival. Moreover, treatment with mitochondrial division inhibitor-1 significantly suppressed tumor growth in an in vivo xenograft nude mice model. Our findings demonstrate that increased mitochondrial fission plays a critical role in regulation of HCC cell survival, which provides a strong evidence for this process as drug target in HCC treatment. PMID:27124102

  16. 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...

  17. Inducible Hsp70 in the Regulation of Cancer Cell Survival: Analysis of Chaperone Induction, Expression and Activity

    Directory of Open Access Journals (Sweden)

    Elisa Zorzi

    2011-10-01

    Full Text Available Understanding the mechanisms that control stress is central to realize how cells respond to environmental and physiological insults. All the more important is to reveal how tumour cells withstand their harsher growth conditions and cope with drug-induced apoptosis, since resistance to chemotherapy is the foremost complication when curing cancer. Intensive research on tumour biology over the past number of years has provided significant insights into the molecular events that occur during oncogenesis, and resistance to anti-cancer drugs has been shown to often rely on stress response and expression of inducible heat shock proteins (HSPs. However, with respect to the mechanisms guarding cancer cells against proteotoxic stresses and the modulatory effects that allow their survival, much remains to be defined. Heat shock proteins are molecules responsible for folding newly synthesized polypeptides under physiological conditions and misfolded proteins under stress, but their role in maintaining the transformed phenotype often goes beyond their conventional chaperone activity. Expression of inducible HSPs is known to correlate with limited sensitivity to apoptosis induced by diverse cytotoxic agents and dismal prognosis of several tumour types, however whether cancer cells survive because of the constitutive expression of heat shock proteins or the ability to induce them when adapting to the hostile microenvironment remains to be elucidated. Clear is that tumours appear nowadays more “addicted” to heat shock proteins than previously envisaged, and targeting HSPs represents a powerful approach and a future challenge for sensitizing tumours to therapy. This review will focus on the anti-apoptotic role of heat shock 70kDa protein (Hsp70, and how regulatory factors that control inducible Hsp70 synthesis, expression and activity may be relevant for response to stress and survival of cancer cells.

  18. Inducible Hsp70 in the Regulation of Cancer Cell Survival: Analysis of Chaperone Induction, Expression and Activity

    Energy Technology Data Exchange (ETDEWEB)

    Zorzi, Elisa [OncoHematology Clinic of Pediatrics, University-Hospital of Padova, 35100 Padova (Italy); Bonvini, Paolo, E-mail: paolo.bonvini@unipd.it [OncoHematology Clinic of Pediatrics, University-Hospital of Padova, 35100 Padova (Italy); Fondazione Città della Speranza, 36030 Monte di Malo, Vicenza (Italy)

    2011-10-21

    Understanding the mechanisms that control stress is central to realize how cells respond to environmental and physiological insults. All the more important is to reveal how tumour cells withstand their harsher growth conditions and cope with drug-induced apoptosis, since resistance to chemotherapy is the foremost complication when curing cancer. Intensive research on tumour biology over the past number of years has provided significant insights into the molecular events that occur during oncogenesis, and resistance to anti-cancer drugs has been shown to often rely on stress response and expression of inducible heat shock proteins (HSPs). However, with respect to the mechanisms guarding cancer cells against proteotoxic stresses and the modulatory effects that allow their survival, much remains to be defined. Heat shock proteins are molecules responsible for folding newly synthesized polypeptides under physiological conditions and misfolded proteins under stress, but their role in maintaining the transformed phenotype often goes beyond their conventional chaperone activity. Expression of inducible HSPs is known to correlate with limited sensitivity to apoptosis induced by diverse cytotoxic agents and dismal prognosis of several tumour types, however whether cancer cells survive because of the constitutive expression of heat shock proteins or the ability to induce them when adapting to the hostile microenvironment remains to be elucidated. Clear is that tumours appear nowadays more “addicted” to heat shock proteins than previously envisaged, and targeting HSPs represents a powerful approach and a future challenge for sensitizing tumours to therapy. This review will focus on the anti-apoptotic role of heat shock 70kDa protein (Hsp70), and how regulatory factors that control inducible Hsp70 synthesis, expression and activity may be relevant for response to stress and survival of cancer cells.

  19. Inducible Hsp70 in the Regulation of Cancer Cell Survival: Analysis of Chaperone Induction, Expression and Activity

    International Nuclear Information System (INIS)

    Understanding the mechanisms that control stress is central to realize how cells respond to environmental and physiological insults. All the more important is to reveal how tumour cells withstand their harsher growth conditions and cope with drug-induced apoptosis, since resistance to chemotherapy is the foremost complication when curing cancer. Intensive research on tumour biology over the past number of years has provided significant insights into the molecular events that occur during oncogenesis, and resistance to anti-cancer drugs has been shown to often rely on stress response and expression of inducible heat shock proteins (HSPs). However, with respect to the mechanisms guarding cancer cells against proteotoxic stresses and the modulatory effects that allow their survival, much remains to be defined. Heat shock proteins are molecules responsible for folding newly synthesized polypeptides under physiological conditions and misfolded proteins under stress, but their role in maintaining the transformed phenotype often goes beyond their conventional chaperone activity. Expression of inducible HSPs is known to correlate with limited sensitivity to apoptosis induced by diverse cytotoxic agents and dismal prognosis of several tumour types, however whether cancer cells survive because of the constitutive expression of heat shock proteins or the ability to induce them when adapting to the hostile microenvironment remains to be elucidated. Clear is that tumours appear nowadays more “addicted” to heat shock proteins than previously envisaged, and targeting HSPs represents a powerful approach and a future challenge for sensitizing tumours to therapy. This review will focus on the anti-apoptotic role of heat shock 70kDa protein (Hsp70), and how regulatory factors that control inducible Hsp70 synthesis, expression and activity may be relevant for response to stress and survival of cancer cells

  20. Autophagy is an important metabolic pathway to determine leukemia cell survival following suppression of the glycolytic pathway.

    Science.gov (United States)

    Kawaguchi, Moemi; Aoki, Shigeki; Hirao, Takuya; Morita, Michie; Ito, Kousei

    2016-05-20

    Most cancer cells predominantly produce energy by glycolysis, even in the presence of adequate oxygen. Therefore, inhibition of glycolysis is a promising cancer treatment target. Recently, it has been recognized that to conduct thorough treatment of cancer, comprehensive understanding of cancer metabolism is essential, not only focusing on glycolysis. Here, we investigated the supporting mechanism of autophagy, which is a catabolic process that recycles intracellular components, for energy supply in the glycolysis-inhibited condition. Autophagy is thought to be highly activated in cancers and to promote their growth or progression by adapting to the harsh surrounding microenvironment. We found that cancer cells positively promoted autophagy to overcome the energy shortage from glycolysis by maintaining mitochondrial activity for ATP production essential for survival. Conclusively, autophagy plays a role in determining whether cancer cells live or die, and autophagic ability in cancer cells is a promising target for therapy. PMID:27107693

  1. Radiation therapy improves survival in rectal small cell cancer - Analysis of Surveillance Epidemiology and End Results (SEER) data

    International Nuclear Information System (INIS)

    Small cell carcinoma of the rectum is a rare neoplasm with scant literature to guide treatment. We used the Surveillance Epidemiology and End Results (SEER) database to investigate the role of radiation therapy in the treatment of this cancer. The SEER database (National Cancer Institute) was queried for locoregional cases of small cell rectal cancer. Years of diagnosis were limited to 1988–2010 (most recent available) to reduce variability in staging criteria or longitudinal changes in surgery and radiation techniques. Two month conditional survival was applied to minimize bias by excluding patients who did not survive long enough to receive cancer-directed therapy. Patient demographics between the RT and No-RT groups were compared using Pearson Chi-Square tests. Overall survival was compared between patients who received radiotherapy (RT, n = 43) and those who did not (No-RT, n = 28) using the Kaplan-Meier method. Multivariate Cox proportional hazards model was used to evaluate important covariates. Median survival was significantly longer for patients who received radiation compared to those who were not treated with radiation; 26 mo vs. 8 mo, respectively (log-rank P = 0.009). We also noted a higher 1-year overall survival rate for those who received radiation (71.1% vs. 37.8%). Unadjusted hazard ratio for death (HR) was 0.495 with the use of radiation (95% CI 0.286-0.858). Among surgery, radiotherapy, sex and age at diagnosis, radiation therapy was the only significant factor for overall survival with a multivariate HR for death of 0.393 (95% CI 0.206-0.750, P = 0.005). Using SEER data, we have identified a significant survival advantage with the use of radiation therapy in the setting of rectal small cell carcinoma. Limitations of the SEER data apply to this study, particularly the lack of information on chemotherapy usage. Our findings strongly support the use of radiation therapy for patients with locoregional small cell rectal cancer

  2. Evaluation of recommended methods for radioisotope red cell survival studies

    International Nuclear Information System (INIS)

    Mean red cell life-span in normal subjects and in patients with various hematological disorders was examined with 51Cr and diisopropylfluorophosphate (DF)32P. The results with 51Cr were corrected for 51Cr elution using correction factors. The results by the two methods agreed fairly well with each other. Elution rate in various hematological disorders was 2.3% per day or less except for the patients with extracorpuscular hemolytic agents such as autoimmune hemolytic anemia or congestive splenomegaly. It is concluded that estimates of mean red cell life-span by corrected 51Cr method are more useful and sufficient than uncorrected 51Cr or DF32P method in general hematological disorders. (auth.)

  3. Mathematical analysis of /sup 51/Cr-labelled red cell survival curves in congenital haemolytic anaemias

    Energy Technology Data Exchange (ETDEWEB)

    Kasfiki, A.G.; Antipas, S.E.; Dimitriou, P.A.; Gritzali, F.A.; Melissinos, K.G.

    1982-04-01

    The parameters of /sup 51/Cr labelled red cell survival curves were calculated in 26 patients with homozygous ..beta..-thalassaemia, 8 with sickle-cell anaemia and 3 with s-..beta..-thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shorting of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s-..beta..-thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors.

  4. Mathematical analysis of 51Cr-labelled red cell survival curves in congenital haemolytic anaemias

    International Nuclear Information System (INIS)

    The parameters of 51Cr labelled red cell survival curves were calculated in 26 patients with homozygous β-thalassaemia, 8 with sickle-cell anaemia and 3 with s-β-thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shorting of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s-β-thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors. (orig.)

  5. 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

  6. The effect of encapsulation of cardiac stem cells within matrix-enriched hydrogel capsules on cell survival, post-ischemic cell retention and cardiac function

    OpenAIRE

    Mayfield, Audrey E.; Tilokee, Everad L.; Latham, Nicholas; McNeill, Brian; Lam, Bu-Khanh; Ruel, Marc; Suuronen, Erik J; Courtman, David W.; Stewart, Duncan J.; Davis, Darryl R.

    2013-01-01

    Transplantation of ex vivo proliferated cardiac stem cells (CSCs) is an emerging therapy for ischemic cardiomyopathy but outcomes are limited by modest engraftment and poor long-term survival. As such, we explored the effect of single cell microencapsulation to increase CSC engraftment and survival after myocardial injection. Transcript and protein profiling of human atrial appendage sourced CSCs revealed strong expression the pro-survival integrin dimers αVβ3 and α5β1- thus rationalizing the...

  7. Autophagy mediates survival of pancreatic tumour-initiating cells in a hypoxic microenvironment.

    Science.gov (United States)

    Rausch, Vanessa; Liu, Li; Apel, Anja; Rettig, Theresa; Gladkich, Jury; Labsch, Sabrina; Kallifatidis, Georgios; Kaczorowski, Adam; Groth, Ariane; Gross, Wolfgang; Gebhard, Martha M; Schemmer, Peter; Werner, Jens; Salnikov, Alexei V; Zentgraf, Hanswalter; Büchler, Markus W; Herr, Ingrid

    2012-07-01

    Involvement of dysregulated autophagy in cancer growth and progression has been shown in different tumour entities, including pancreatic ductal adenocarcinoma (PDA). PDA is an extremely aggressive tumour characterized by a small population of highly therapy-resistant cancer stem cells (CSCs) capable of self-renewal and migration. We examined whether autophagy might be involved in the survival of CSCs despite nutrition and oxygen deprivation typical for the hypoxic tumour microenvironment of PDA. Immunohistochemistry revealed that markers for hypoxia, CSCs and autophagy are co-expressed in patient-derived tissue of PDA. Hypoxia starvation (H/S) enhanced clonogenic survival and migration of established pancreatic cancer cells with stem-like properties (CSC(high)), while pancreatic tumour cells with fewer stem cell markers (CSC(low)) did not survive these conditions. Electron microscopy revealed more advanced autophagic vesicles in CSC(high) cells, which exhibited higher expression of autophagy-related genes under normoxic conditions and relative to CSC(low) cells, as found by RT-PCR and western blot analysis. LC3 was already fully converted to the active LC3-II form in both cell lines, as evaluated by western blot and detection of accumulated GFP-LC3 protein by fluorescence microscopy. H/S increased formation of autophagic and acid vesicles, as well as expression of autophagy-related genes, to a higher extent in CSC(high) cells. Modulation of autophagy by inhibitors and activators resensitized CSC(high) to apoptosis and diminished clonogenicity, spheroid formation, expression of CSC-related genes, migratory activity and tumourigenicity in mice. Our data suggest that enhanced autophagy levels may enable survival of CSC(high) cells under H/S. Interference with autophagy-activating or -inhibiting drugs disturbs the fine-tuned physiological balance of enhanced autophagy in CSC and switches survival signalling to suicide. PMID:22262369

  8. A comparison of methods of determining the 100 percent survival of preserved red cells

    International Nuclear Information System (INIS)

    Studies were done to compare three methods to determine the 100 percent survival value from which to estimate the 24-hour posttransfusion survival of preserved red cells. The following methods using small aliquots of 51Cr-labeled autologous preserved red cells were evaluated: First, the 125I-albumin method, which is an indirect measurement of the recipient's red cell volume derived from the plasma volume measured using 125I-labeled albumin and the total body hematocrit. Second, the body surface area method (BSA) in which the recipient's red cell volume is derived from a body surface area nomogram. Third, an extrapolation method, which extrapolates to zero time the radioactivity associated with the red cells in the recipient's circulation from 10 to 20 or 15 to 30 minutes after transfusion. The three methods gave similar results in all studies in which less than 20 percent of the transfused red cells were nonviable (24-hour posttransfusion survival values of between 80-100%), but not when more than 20 percent of the red cells were nonviable. When 21 to 35 percent of the transfused red cells were nonviable (24-hour posttransfusion survivals of 65 to 79%), values with the 125I-albumin method and the body surface area method were about 5 percent lower (p less than 0.001) than values with the extrapolation method. When greater than 35 percent of the red cells were nonviable (24-hour posttransfusion survival values of less than 65%), values with the 125I-albumin method and the body surface area method were about 10 percent lower (p less than 0.001) than those obtained by the extrapolation method

  9. Role of Ca resistance in competitive survival of fluorescent Pseudomonas in soil with high salinity

    International Nuclear Information System (INIS)

    The Ca2+-resistant strain HR2-6 of Pseudomonas putida was isolated from spinach root grown in a greenhouse in high salinity soil. Since Ca often accumulates in greenhouse soils in Japan due to many years of Ca applications, the role of Ca2+ resistance in the survival of the strain was investigated. To conduct the investigation, Ca2+-sensitive mutants were obtained with UV-irradiation. The Ca2+-sensitive mutant CAS-1 was found to grow as well as the wild type HR2-6 in a TSB medium without added Ca2+, but with 150 mM and 200 mM Ca2+ added, the growth of the Ca2+-sensitive mutants were 7- and 56-fold lower than that of the wild type. In sterile spinach-greenhouse soil (a non-competitive environment), populations of the Ca2+-sensitive mutant and wild-type strain were similar, but in nonsterile greenhouse soil (a competitive environment), populations of the Ca2+-sensitive mutant were 112-fold lower than the wild type after 50 days. These data suggest that Ca2+ resistance can be an important factor in the survival of P. putida in soil that has an accumulation of Ca

  10. 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

    PURPOSE: Somatic alterations have been shown to correlate with ovarian cancer prognosis and survival, but less is known about the effects on survival of common inherited genetic variation. Of particular interest are genes involved in cell cycle pathways, which regulate cell division and could...... 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......) and survival among women with invasive ovarian cancer participating in a multicenter case-control study from United Kingdom, Denmark, and United States. DNAs from up to 1,499 women were genotyped for 97 single-nucleotide polymorphisms that tagged the known common variants (minor allele frequency > or = 0...

  11. The initial slope of cell survival curves. Its implications in radiotherapy

    International Nuclear Information System (INIS)

    The problem of the initial slope of the cell survival curves can be approached in 2 ways: a straightforward approach is the direct and acurate measurement of the cell survival at low dose. This method is practically restricted to experiments in vitro; an indirect approach is the determination of the initial slope of the single cell survival curves from the shape of the ''isoeffect curves'' for fractionated irradiations. This method can be applied to ''non-quantitative'' reactions. Implications in radiotherapy of the existence of a significant initial slope are presented with respect to the 3 following problems: importance of the fraction number N for fractionated irradiations with small doses per fraction and differential effect related to fraction number; variation of the total dose as a function of dose rate for low dose rate irradiation; RBE of high LET radiation and RBE/dose relationship

  12. 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

  13. A new scoring system for predicting survival in patients with non-small cell lung cancer

    International Nuclear Information System (INIS)

    This analysis was performed to create a scoring system to estimate the survival of patients with non-small cell lung cancer (NSCLC). Data from 1274 NSCLC patients were analyzed to create and validate a scoring system. Univariate (UV) and multivariate (MV) Cox models were used to evaluate the prognostic importance of each baseline factor. Prognostic factors that were significant on both UV and MV analyses were used to develop the score. These included quality of life, age, performance status, primary tumor diameter, nodal status, distant metastases, and smoking cessation. The score for each factor was determined by dividing the 5-year survival rate (%) by 10 and summing these scores to form a total score. MV models and the score were validated using bootstrapping with 1000 iterations from the original samples. The score for each prognostic factor ranged from 1 to 7 points with higher scores reflective of better survival. Total scores (sum of the scores from each independent prognostic factor) of 32–37 correlated with a 5-year survival of 8.3% (95% CI = 0–17.1%), 38–43 correlated with a 5-year survival of 20% (95% CI = 13–27%), 44–47 correlated with a 5-year survival of 48.3% (95% CI = 41.5–55.2%), 48–49 correlated to a 5-year survival of 72.1% (95% CI = 65.6–78.6%), and 50–52 correlated to a 5-year survival of 84.7% (95% CI = 79.6–89.8%). The bootstrap method confirmed the reliability of the score. Prognostic factors significantly associated with survival on both UV and MV analyses were used to construct a valid scoring system that can be used to predict survival of NSCLC patients. Optimally, this score could be used when counseling patients, and designing future trials

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

    OpenAIRE

    Ivana Márcia Alves Diniz; Adriana Bona Matos; Márcia Martins Marques

    2015-01-01

    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...

  15. 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.

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

    Science.gov (United States)

    Parker, Jennifer Janell

    Radiation therapy is a widely used cancer treatment that has the potential to influence anti-tumor immune responses. Both myeloablative and non-myeloablative radiation are often used as part of preparatory regimens for hematopoetic stem cell transplantation, in combination with other chemotherapy or immuno-modulatory (e.g. Anti-thymocyte globulin (ATG)) therapies for both cytotoxic and immune modulatory purposes. However, the mechanisms responsible for the effect of radiation on antigen presenting cell (APC) responsiveness and radioresistance are poorly understood. The first studies described in this thesis were designed to identify and characterize early radiation-induced signaling changes in antigen presenting cells and to determine the effects of these signaling changes on APC receptor expression and function. The NFkappaB pathway in antigen presenting cells was chosen for study because it is activated by radiation in a wide range of other cell types and plays a vital role in the maintenance and regulation of the immune system. The effects of therapeutically relevant doses radiation (2 and 20 Gy) were compared at various timepoints in the human monocytic cell line (U937) using phospho-flow cytometry staining methods and cytometric analysis. These studies demonstrated that radiation-induced changes in the phosphorylation state of NFkappaB family members that were p53 independent. However, these changes were dependent upon activation of ATM in response to single or double-stranded breaks in DNA, as shown in experiments using an inhibitor of ATM and ATM siRNA knockdown U937 cells. In addition, studies examining the effect of radiation on co-stimulatory receptors with and without inhibition of the NFkappaB pathway via phospho-flow cytometry revealed that radiation-induced phosphorylation of NEMO promoted the activation and functional maturation of U937 cells. Furthermore, functional studies using both phospho-flow cytometry and/or mixed lymphocyte reactions to

  17. In vivo vascularization of cell sheets provided better long-term tissue survival than injection of cell suspension.

    Science.gov (United States)

    Takeuchi, Ryohei; Kuruma, Yosuke; Sekine, Hidekazu; Dobashi, Izumi; Yamato, Masayuki; Umezu, Mitsuo; Shimizu, Tatsuya; Okano, Teruo

    2016-08-01

    Cell sheets have shown a remarkable ability for repairing damaged myocardium in clinical and preclinical studies. Although they demonstrate a high degree of viability as engrafted cells in vivo, the reason behind their survivability is unclear. In this study, the survival and vascularization of rat cardiac cell sheets transplanted in the subcutaneous tissue of athymic rats were investigated temporally. The cell sheets showed significantly higher survival than cell suspensions for up to 12 months, using an in vivo bioluminescence imaging system to detect luciferase-positive transplanted cells. Terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay also showed a smaller number of apoptotic cells in the cell sheets than in the cell suspensions at 1 day. Rapid vascular formation and maturation were observed inside the cell sheets using an in vivo imaging system. Leaky vessels appeared at 6 h, red blood cells flowing through functional vessels appeared at 12 h, and morphologically matured vessels appeared at 7 days. In addition, immunostaining of cell sheets with nerve/glial antigen-2 (NG2) showed that vessel maturity increased over time. Interestingly, these results correlated with the dynamics of cell sheet mRNA expression. Genes related to endothelial cells (ECs) proliferation, migration and vessel sprouting were highly expressed within 1 day, and genes related to pericyte recruitment and vessel maturation were highly expressed at 3 days or later. This suggested that the cell sheets could secrete appropriate angiogenic factors in a timely way after transplantation, and this ability might be a key reason for their high survival. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24470393

  18. The survival of cryopreserved human bone marrow stem cells.

    Science.gov (United States)

    Hill, R S; Mackinder, C A; Postlewaight, B F; Blacklock, H A

    1979-07-01

    Two methods for cryopreservation of bone marrow stem cells were compared using bone marrow obtained from 36 patients. Included in this group were 21 persons with the diagnosis of leukaemia including 14 either with acute myeloid or lymphoblastic leukaemia in remission following intensive remission induction chemotherapy. After freeze-preservation and reconstitution, all marrow samples were tested for nucleated cell (NC) recovery and grown on agar to assess colony forming units (CFUC) and cluster forming units in culture (CluFUc). A slow dilution reconstitution method using freezing media containing AB negative plasma resulted in recovery of 85% of the CFUc activity of fresh marrow. This result was significantly better than the 47% CFUc recovery obtained when freezing media without plasma and a rapid dilution reconstitution technique were used. NC recoveries following slow dilution (51%) and rapid dilution (44%) were not significantly different. CluFUc were disproportionately reduced compared with CFUc although yielding similar results with both methods (26% and 32%). No correlation was found for either method between CFUc and NC recovery or between CFUc and CluFUc recovery in cryopreserved bone marrow. PMID:392422

  19. Therapeutic Efficacy of Stem Cells Transplantation in Diabetes: Role of Heme Oxygenase

    Science.gov (United States)

    Raffaele, Marco; Li Volti, Giovanni; Barbagallo, Ignazio A.; Vanella, Luca

    2016-01-01

    The growing data obtained from in vivo studies and clinical trials demonstrated the benefit of adult stem cells transplantation in diabetes; although an important limit is represented by their survival after the transplant. To this regard, recent reports suggest that genetic manipulation of stem cells prior to transplantation can lead to enhanced survival and better engraftment. The following review proposes to stimulate interest in the role of heme oxygenase-1 over-expression on transplantation of stem cells in diabetes, focusing on the clinical potential of heme oxygenase protein and activity to restore tissue damage and/or to improve the immunomodulatory properties of transplanted stem cells.

  20. mTORC2 coordinates pulmonary artery smooth muscle cell metabolism, proliferation and survival in pulmonary arterial hypertension

    Science.gov (United States)

    Goncharov, Dmitry A.; Kudryashova, Tatiana V.; Ziai, Houman; Ihida-Stansbury, Kaori; DeLisser, Horace; Krymskaya, Vera P.; Tuder, Rubin M.; Kawut, Steven M.; Goncharova, Elena A.

    2014-01-01

    Background Enhanced proliferation, resistance to apoptosis and metabolic shift to glycolysis of pulmonary arterial vascular smooth muscle cells (PAVSMC) are key pathophysiological components of pulmonary vascular remodeling in idiopathic pulmonary arterial hypertension (IPAH). The role of distinct mTOR complexes mTORC1 (mTOR-raptor) and mTORC2 (mTOR-rictor) in PAVSMC proliferation and survival in PAH and their therapeutic relevance is unknown. Methods and Results Immunohistochemical and immunoblot analyses revealed that mTORC1 and mTORC2 pathways are markedly up-regulated in small remodeled PAs and isolated distal PAVSMC from IPAH subjects that have increased ATP levels, proliferation and survival that depend on glycolytic metabolism. siRNA- and pharmacological-based analysis showed that while both mTORC1 and mTORC2 contributing to proliferation, only mTORC2 is required for ATP generation and survival of IPAH PAVSMC. mTORC2 down-regulated energy sensor AMPK allowing activation of mTORC1-S6 and increased proliferation, and deficiency of pro-apoptotic protein Bim and IPAH PAVSMC survival. Nox4 protein levels were increased in IPAH PAVSMC that was necessary for mTORC2 activation, proliferation and survival. Nox4 levels and mTORC2 signaling were significantly up-regulated in small PAs from hypoxia-exposed rats at days 2-28 of hypoxia. Treatment with the mTOR kinase inhibitor PP242 at days 15-28 suppressed mTORC2, but not Nox4, induced SM-specific apoptosis in small PAs and reversed hypoxia-induced pulmonary vascular remodeling in rats. Conclusions These data provide a novel mechanistic link of Nox4-dependent activation of mTORC2 via energy sensor AMPK to increased proliferation and survival of PAVSMC in PAH suggesting a new potential pathway for the therapeutic interventions. PMID:24270265

  1. The Hug-Kellerer equation as the universal cell survival curve

    Energy Technology Data Exchange (ETDEWEB)

    Ekstrand, Kenneth E [Department of Radiation Oncology, Wake Forest University School of Medicine, Winston-Salem, NC 27157 (United States)

    2010-05-21

    The Hug-Kellerer (H-K) equation is one of the earliest proposed radiation cell survival curves. We examine this equation in view of the recent perceived need for a universal cell survival curve which would be applicable to single radiation fractions at high doses. We derive relationships between the three parameters of the H-K equation and the parameters {alpha} and {beta} of the linear-quadratic equation. Using these relationships we show how the H-K equation can be used to determine single-fraction doses which are equivalent in theory to the dose in a conventional multi-fraction course of radiation therapy. (note)

  2. The Hug-Kellerer equation as the universal cell survival curve

    International Nuclear Information System (INIS)

    The Hug-Kellerer (H-K) equation is one of the earliest proposed radiation cell survival curves. We examine this equation in view of the recent perceived need for a universal cell survival curve which would be applicable to single radiation fractions at high doses. We derive relationships between the three parameters of the H-K equation and the parameters α and β of the linear-quadratic equation. Using these relationships we show how the H-K equation can be used to determine single-fraction doses which are equivalent in theory to the dose in a conventional multi-fraction course of radiation therapy. (note)

  3. 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.

  4. Bone-Marrow Stem-Cell Survival in the Non-Uniformly Exposed Mammal

    International Nuclear Information System (INIS)

    For comparison of the effectiveness of non-uniform versus uniform irradiations in causing haematological death in mammals, a model of the irradiated haemopoietic system has been proposed. The essential features of this model are: (1) that different parts of the haemopoietic system have numbers of stem cells which are proportioned to the amounts of active marrow in those parts as measured by 59Fe uptake, (2) that stem cells in the different parts are subject to the, same dose-survival relationship, and (3) that survival of the animal depends on survival of a critical fraction of the total number of stem cells independent of their distribution among the parts of the total marrow mass. To apply this model one needs to know: (a) the relative 59Fe uptakes of the different parts of the haemopoietic system, (b) the doses delivered to those parts by each of the exposures to be compared, and (c) the dose-survival curve applicable to the stem cells. From these one can calculate the fraction of stem cells surviving each exposure. In a preliminary communication the applicability of the model was investigated using data obtained entirely from the literature. Additional data, particularly on bone-marrow distribution, have since been obtained and are included here. The primary object of the present paper is to test further the validity of the above 'stem-cell survival model'. Data on bilateral (essentially uniform) versus unilateral and non-uniform rotational exposures in mammals are examined with respect to the surviving fraction of stem cells at the LD50/30 day dose level. Although an adequate test is not possible at present for lack of a full set of data in any one species, a partial test indicates compatibility with data for dogs and rats. Other possible mortality determinants such as doses or exposures at entrance, midline or exit, or the gram-rads or average dose to the marrow, appear to be less useful than the critical stem-cell survival fraction

  5. Action of caffeine on the survival of x-irradiated cells

    International Nuclear Information System (INIS)

    Post-irradiation treatment of HeLa S3 cells with 1 mM caffeine results in a marked diminution of the surviving fraction as scored by colony formation. The decrease is dose-dependent; the effect of a 24-h post-irradiation treatment of a non-synchronous population with caffeine is to change the terminal slope of the survival curve and its intercept. Do is reduced from 130 to 60 rad; the extrapolation number is increased about twofold. The amount of post-irradiation killing is maximal if cells are exposed to caffeine at a concentration of at least 1 mM for 8 hours; less than 10% of unirradiated cells are killed under these conditions. Dose-response curves were also obtained for synchronous cells at various phases of the cell cycle. Similar results were obtained at all cell ages, but the magnitude of the effect is age-dependent. This age dependence was further explored in experiments in which mitotically collected cells were exposed to 300 or 500 rad doses at 2-hour intervals throughout the cell cycle. Treatment with caffeine for 24 hours after irradiation enhances the killing of cells late in the cycle more than in G1. The sensitivities of two other cell lines, CHO and EMT6, also were examined; both are substantially less sensitive to caffeine. The smaller cell-cycle dependence of CHO cells is qualitatively the same as that of HeLa cells

  6. Abundance of early functional HIV-specific CD8+ T cells does not predict AIDS-free survival time.

    Directory of Open Access Journals (Sweden)

    Ingrid M M Schellens

    Full Text Available BACKGROUND: T-cell immunity is thought to play an important role in controlling HIV infection, and is a main target for HIV vaccine development. HIV-specific central memory CD8(+ and CD4(+ T cells producing IFNgamma and IL-2 have been associated with control of viremia and are therefore hypothesized to be truly protective and determine subsequent clinical outcome. However, the cause-effect relationship between HIV-specific cellular immunity and disease progression is unknown. We investigated in a large prospective cohort study involving 96 individuals of the Amsterdam Cohort Studies with a known date of seroconversion whether the presence of cytokine-producing HIV-specific CD8(+ T cells early in infection was associated with AIDS-free survival time. METHODS AND FINDINGS: The number and percentage of IFNgamma and IL-2 producing CD8(+ T cells was measured after in vitro stimulation with an overlapping Gag-peptide pool in T cells sampled approximately one year after seroconversion. Kaplan-Meier survival analysis and Cox proportional hazard models showed that frequencies of cytokine-producing Gag-specific CD8(+ T cells (IFNgamma, IL-2 or both shortly after seroconversion were neither associated with time to AIDS nor with the rate of CD4(+ T-cell decline. CONCLUSIONS: These data show that high numbers of functional HIV-specific CD8(+ T cells can be found early in HIV infection, irrespective of subsequent clinical outcome. The fact that both progressors and long-term non-progressors have abundant T cell immunity of the specificity associated with low viral load shortly after seroconversion suggests that the more rapid loss of T cell immunity observed in progressors may be a consequence rather than a cause of disease progression.

  7. The Role of the Immune Response in Merkel Cell Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Triozzi, Pierre L., E-mail: triozzp@ccf.org [Taussig Cancer Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Fernandez, Anthony P. [Departments of Dermatology and Anatomic Pathology, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195 (United States)

    2013-02-28

    Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer. The Merkel cell polyomavirus (MCPyV) is implicated in its pathogenesis. Immune mechanisms are also implicated. Patients who are immunosuppressed have an increased risk. There is evidence that high intratumoral T-cell counts and immune transcripts are associated with favorable survival. Spontaneous regressions implicate immune effector mechanisms. Immunogenicity is also supported by observation of autoimmune paraneoplastic syndromes. Case reports suggest that immune modulation, including reduction of immune suppression, can result in tumor regression. The relationships between MCPyV infection, the immune response, and clinical outcome, however, remain poorly understood. Circulating antibodies against MCPyV antigens are present in most individuals. MCPyV-reactive T cells have been detected in both MCC patients and control subjects. High intratumoral T-cell counts are also associated with favorable survival in MCPyV-negative MCC. That the immune system plays a central role in preventing and controlling MCC is supported by several observations. MCCs often develop, however, despite the presence of humoral and cellular immune responses. A better understanding on how MCPyV and MCC evade the immune response will be necessary to develop effective immunotherapies.

  8. The Role of the Immune Response in Merkel Cell Carcinoma

    International Nuclear Information System (INIS)

    Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer. The Merkel cell polyomavirus (MCPyV) is implicated in its pathogenesis. Immune mechanisms are also implicated. Patients who are immunosuppressed have an increased risk. There is evidence that high intratumoral T-cell counts and immune transcripts are associated with favorable survival. Spontaneous regressions implicate immune effector mechanisms. Immunogenicity is also supported by observation of autoimmune paraneoplastic syndromes. Case reports suggest that immune modulation, including reduction of immune suppression, can result in tumor regression. The relationships between MCPyV infection, the immune response, and clinical outcome, however, remain poorly understood. Circulating antibodies against MCPyV antigens are present in most individuals. MCPyV-reactive T cells have been detected in both MCC patients and control subjects. High intratumoral T-cell counts are also associated with favorable survival in MCPyV-negative MCC. That the immune system plays a central role in preventing and controlling MCC is supported by several observations. MCCs often develop, however, despite the presence of humoral and cellular immune responses. A better understanding on how MCPyV and MCC evade the immune response will be necessary to develop effective immunotherapies

  9. The ubiquitin ligase Nedd4 regulates craniofacial development by promoting cranial neural crest cell survival and stem-cell like properties.

    Science.gov (United States)

    Wiszniak, Sophie; Kabbara, Samuela; Lumb, Rachael; Scherer, Michaela; Secker, Genevieve; Harvey, Natasha; Kumar, Sharad; Schwarz, Quenten

    2013-11-15

    The integration of multiple morphogenic signalling pathways and transcription factor networks is essential to mediate neural crest (NC) cell induction, delamination, survival, stem-cell properties, fate choice and differentiation. Although the transcriptional control of NC development is well documented in mammals, the role of post-transcriptional modifications, and in particular ubiquitination, has not been explored. Here we report an essential role for the ubiquitin ligase Nedd4 in cranial NC cell development. Our analysis of Nedd4(-/-) embryos identified profound deficiency of cranial NC cells in the absence of structural defects in the neural tube. Nedd4 is expressed in migrating cranial NC cells and was found to positively regulate expression of the NC transcription factors Sox9, Sox10 and FoxD3. We found that in the absence of these factors, a subset of cranial NC cells undergo apoptosis. In accordance with a lack of cranial NC cells, Nedd4(-/-) embryos have deficiency of the trigeminal ganglia, NC derived bone and malformation of the craniofacial skeleton. Our analyses therefore uncover an essential role for Nedd4 in a subset of cranial NC cells and highlight E3 ubiquitin ligases as a likely point of convergence for multiple NC signalling pathways and transcription factor networks. PMID:24080509

  10. To Die or to Survive, a Fatal Question for the Destiny of Prostate Cancer Cells after Androgen Deprivation Therapy

    International Nuclear Information System (INIS)

    Prostate cancer is the most frequently diagnosed non-skin cancer in adult males in North America and is the second leading cause of cancer-related mortality. For locally advanced or metastatic disease, androgen deprivation, through medical or surgical castration, is the primary treatment to induce prostate cancer cell death and extend patient survival. However, the vast majority of cancers progress to a castration-resistant/androgen-independent state where the cell death processes are no longer active. This review describes the main cell death processes, apoptosis, autophagy, necrosis and necroptosis, which may be activated in prostate cancers after androgen deprivation therapy as well as the molecular mechanisms through which the cancers progress to become castration resistant. In particular, the central role of persistent androgen receptor (AR)-mediated signaling and AR crosstalk with other critical cell signaling pathways, including (i) the PI3K/Akt pathway, (ii) receptor tyrosine kinases, (iii) the p38 MAPK pathway, and (iv) the Wnt/β-catenin pathway, as well as reactivation of AR by de novo synthesized androgen are discussed in this context. Understanding the molecular changes that subvert normal cell death mechanisms and thereby compromise the survival of prostate cancer patients continues to be a major challenge

  11. To Die or to Survive, a Fatal Question for the Destiny of Prostate Cancer Cells after Androgen Deprivation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Kai-Xin; Firus, Jessica; Prieur, Brenda [The Vancouver Prostate Centre, 2660 Oak St., Vancouver, BC V6H 3Z6 (Canada); Department of Urologic Sciences, University of British Columbia, Vancouver, BC V6H 3Z6 (Canada); Jia, William [Department of Surgery and Brain Research Centre, University of British Columbia, Vancouver, BC V6H 3Z6 (Canada); Rennie, Paul S., E-mail: prennie@interchange.ubc.ca [The Vancouver Prostate Centre, 2660 Oak St., Vancouver, BC V6H 3Z6 (Canada); Department of Urologic Sciences, University of British Columbia, Vancouver, BC V6H 3Z6 (Canada)

    2011-03-24

    Prostate cancer is the most frequently diagnosed non-skin cancer in adult males in North America and is the second leading cause of cancer-related mortality. For locally advanced or metastatic disease, androgen deprivation, through medical or surgical castration, is the primary treatment to induce prostate cancer cell death and extend patient survival. However, the vast majority of cancers progress to a castration-resistant/androgen-independent state where the cell death processes are no longer active. This review describes the main cell death processes, apoptosis, autophagy, necrosis and necroptosis, which may be activated in prostate cancers after androgen deprivation therapy as well as the molecular mechanisms through which the cancers progress to become castration resistant. In particular, the central role of persistent androgen receptor (AR)-mediated signaling and AR crosstalk with other critical cell signaling pathways, including (i) the PI3K/Akt pathway, (ii) receptor tyrosine kinases, (iii) the p38 MAPK pathway, and (iv) the Wnt/β-catenin pathway, as well as reactivation of AR by de novo synthesized androgen are discussed in this context. Understanding the molecular changes that subvert normal cell death mechanisms and thereby compromise the survival of prostate cancer patients continues to be a major challenge.

  12. MicroRNA-146a modulates human bronchial epithelial cell survival in response to the cytokine-induced apoptosis

    International Nuclear Information System (INIS)

    MicroRNA plays an important role in cell differentiation, proliferation and cell death. The current study found that miRNA-146a was up-regulated in human bronchial epithelial cells (HBECs) in response to stimulation by TGF-ss1 plus cytomix (a mixture of IL-1ss, IFN-γ and TNF-α). TGF-ss1 plus cytomix (TCM) induced apoptosis in HBECs (3.4 ± 0.6% of control vs 83.1 ± 4.0% of TCM treated cells, p < 0.01), and this was significantly blocked by the miRNA-146a mimic (8.8 ± 1.5%, p < 0.01). In contrast, a miRNA-146a inhibitor had only a modest effect on cell survival but appeared to augment the induction of epithelial-mesenchymal transition (EMT) in response to the cytokines. The MicroRNA-146a mimic appears to modulate HBEC survival through a mechanism of up-regulating Bcl-XL and STAT3 phosphorylation, and by this mechanism it could contribute to tissue repair and remodeling.

  13. Host cell cytotoxicity, cellular repopulation dynamics, and phase-specific cell survival in X-irradiated rat rhabdomyosarcoma tumors

    International Nuclear Information System (INIS)

    Postirradiation tumor volume response, cellular repopulation dynamics, cell-cycle perturbations, and phase-specific cell survival were characterized in rat rhabdomyosarcoma R-1 tumors (the R2C5 subline) following an in situ 10-Gy dose of 225-kVp X rays. This X-ray dose produced a 7.5-day delay in tumor growth to twice the volume measured at the time of irradiation, and reduced the initial surviving fraction of R2C5 cells to 0.17 as measured by the excision assay procedure. The surviving fraction of R2C5 cells returned to unity by the 16th day after tumor irradiation. On the basis of flow cytometry measurements of DNA content in tumor cells stained with a noncytotoxic concentration of Hoechst 33342, a transient G2 block was observed 1 day after irradiation. Flow cytometry measurements also demonstrated that the tetraploid R2C5 cells constituted only 30% of the total tumor cell population, with the remainder being diploid host cells comprised of macrophages, monocytes, lymphocytes, and granulocytes. Large numbers of host cells infiltrated the irradiated tumors, leading to an increase in the percentage of diploid cells by Day 2 and reaching a level of more than 80% of the total tumor cell population by 4 to 8 days after irradiation. The influx of host cells into irradiated tumors was correlated temporally with a significant 12-fold decrease in the surviving fraction of R2C5 cells that occurred between Days 2 and 4 postirradiation. When the diploid host cell population was removed by cell sorting procedures, the surviving fraction of R2C5 cells at Day 4 substantially greater than that in the presence of the host cells. Experiments involving the mixing of 4/1 and 12/1 ratios of diploid host cells and tetraploid tumor cells isolated from irradiated and unirradiated tumors demonstrated that the cytotoxic effect of the host cells was specific for the irradiated tumor cells

  14. A diffusible signal derived from hematopoietic cells supports the survival and proliferation of regenerative cells during zebrafish fin fold regeneration.

    Science.gov (United States)

    Hasegawa, Tomoya; Nakajima, Teruhiro; Ishida, Takashi; Kudo, Akira; Kawakami, Atsushi

    2015-03-01

    Multicellular organisms maintain body integrity by constantly regenerating tissues throughout their lives; however, the overall mechanism for regulating regeneration remains an open question. Studies of limb and fin regeneration in teleost fish and urodeles have shown the involvement of a number of locally activated signals at the wounded site during regeneration. Here, we demonstrate that a diffusible signal from a distance also play an essential role for regeneration. Among a number of zebrafish mutants, we found that the zebrafish cloche (clo) and tal1 mutants, which lack most hematopoietic tissues, displayed a unique regeneration defect accompanying apoptosis in primed regenerative tissue. Our analyses of the mutants showed that the cells in the primed regenerative tissue are susceptible to apoptosis, but their survival is normally supported by the presence of hematopoietic tissues, mainly the myeloid cells. We further showed that a diffusible factor in the wild-type body fluid mediates this signal. Thus, our study revealed a novel mechanism that the hematopoietic tissues regulate tissue regeneration through a diffusible signal. PMID:25533245

  15. Predicting the clonogenic survival of A549 cells after modulated x-ray irradiation using the linear quadratic model

    Energy Technology Data Exchange (ETDEWEB)

    Bromley, Regina; Oliver, Lyn [Northern Sydney Cancer Centre, Radiation Oncology, Royal North Shore Hospital, Sydney, NSW 2065 (Australia); Davey, Ross; Harvie, Rozelle [Department of Medical Oncology, Bill Walsh Cancer Research Laboratories, Royal North Shore Hospital, Sydney, NSW 2065 (Australia); Baldock, Clive [Institute of Medical Physics, School of Physics, Sydney University, NSW 2006 (Australia)

    2009-01-21

    In this study we present two prediction methods, mean dose and summed dose, for predicting the number of A549 cells that will survive after modulated x-ray irradiation. The prediction methods incorporate the dose profile from the modulated x-ray fluence map applied across the cell sample and the linear quadratic (LQ) model. We investigated the clonogenic survival of A549 cells when irradiated using two different modulated x-ray fluence maps. Differences between the measured and predicted surviving fraction were observed for modulated x-ray irradiation. When the x-ray fluence map produced a steep dose gradient across the sample, fewer cells survived in the unirradiated region than expected. When the x-ray fluence map produced a less steep dose gradient across the sample, more cells survived in the unirradiated region than expected. Regardless of the steepness of the dose gradient, more cells survived in the irradiated region than expected for the reference dose range of 1-10 Gy. The change in the cell survival for the unirradiated regions of the two different dose gradients may be an important factor to consider when predicting the number of cells that will survive at the edge of modulated x-ray fields. This investigation provides an improved method of predicting cell survival for modulated x-ray radiation treatment. It highlights the limitations of the LQ model, particularly in its ability to describe the biological response of cells irradiated under these conditions.

  16. Predicting the clonogenic survival of A549 cells after modulated x-ray irradiation using the linear quadratic model

    Science.gov (United States)

    Bromley, Regina; Oliver, Lyn; Davey, Ross; Harvie, Rozelle; Baldock, Clive

    2009-01-01

    In this study we present two prediction methods, mean dose and summed dose, for predicting the number of A549 cells that will survive after modulated x-ray irradiation. The prediction methods incorporate the dose profile from the modulated x-ray fluence map applied across the cell sample and the linear quadratic (LQ) model. We investigated the clonogenic survival of A549 cells when irradiated using two different modulated x-ray fluence maps. Differences between the measured and predicted surviving fraction were observed for modulated x-ray irradiation. When the x-ray fluence map produced a steep dose gradient across the sample, fewer cells survived in the unirradiated region than expected. When the x-ray fluence map produced a less steep dose gradient across the sample, more cells survived in the unirradiated region than expected. Regardless of the steepness of the dose gradient, more cells survived in the irradiated region than expected for the reference dose range of 1-10 Gy. The change in the cell survival for the unirradiated regions of the two different dose gradients may be an important factor to consider when predicting the number of cells that will survive at the edge of modulated x-ray fields. This investigation provides an improved method of predicting cell survival for modulated x-ray radiation treatment. It highlights the limitations of the LQ model, particularly in its ability to describe the biological response of cells irradiated under these conditions.

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

    OpenAIRE

    Wang Xiao-Yang; Penalva Luiz OF; Yuan Hongyan; Linnoila R Ilona; Lu Jiachun; Okano Hideyuki; Glazer Robert I

    2010-01-01

    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 ...

  18. The effect of vitamin E on cellular survival after X irradiation of lymphoma cells

    International Nuclear Information System (INIS)

    Asynchronous cultures of a lymphocytic mouse leukaemic cell line L5178Y were X-irradiated under oxic and hypoxic conditions. The survival curves had almost no shoulder when the cells were grown under normal conditions and then irradiated in the presence of vitamin E, whereas a clear shoulder appeared when the cells were grown and irradiated in a medium supplemented with vitamin E (100 μg/ml). There was no change in the final sensitivity to lethal events in the vitamin E enriched cells. The results suggest that the radioprotective effect of vitamin E depends on its incorporation into the cell membranes. (U.K.)

  19. Role of Cell-Cell bond for the viability and the function of vascular smooth muscle cells

    Directory of Open Access Journals (Sweden)

    M. Mura

    2010-01-01

    Full Text Available Vascular smooth muscle cell (VSMC viability and homeostasis is regulated by cell-matrix and cell-cell contact: disruption of these interactions are responsible of a switch from a mature to a high proliferative phenotype. VSMCs migration, rate of growth and apoptosis, and the extent of their extracellular matrix (ECM deposition can be also modulated by proatherogenic peptides. Among them, ATII induces the transactivation of IGF I R, which, together with the binding protein IGFBP3, represents a determinant of cell survival, growth and proliferation. Aim of our in vitro study was to verify the role of elective cell-cell bond in moulating the response to ATII. Thus, we evaluated viability, proliferation, IGFIR, IGFBP3 expression and the long term survival and production of ECM in a provisional tissue. A7r5 cell-line was used in adherent cultures or incubated in agarose-coated culture plates to inhibit cell-matrix interactions. Cells, treated or not with ATII 100 nM, were evaluated for apoptosis rate, cell cycle, IGFIR and IGFBP3 protei expression. Fibrin provisional tissue was developed polymerizing a fibrin solution. cantaining A7r5 cells with thrombin. Histological stainings for ECM components were performed on sections of prvisional tissue. An exclusive cell-cell contact resulted to monolayer cell cultures. ATII did not affect the cell survival in both culture conditions, but promoted a 10% decrease in "S" phase and an increases IGFIR expression only in adherent cells. while suspended cell aggregates were resistant to ATII administration; IGFBP3 was reduced both in ATII treated adherent cells and in floating clustered cells, irrespective of the treatmentn. VSMC conditioning in agarose-coated plates before seeding in fibrin provisional matrix reduced, but not abolished, the cell ability to colonize the clot and to produce ECM. This study demonstrates that the elective cell-cell contact induces a quiescent status in cells lacking of cell

  20. Metallodrug induced apoptotic cell death and survival attempts are characterizable by Raman spectroscopy

    Science.gov (United States)

    le Roux, K.; Prinsloo, L. C.; Meyer, D.

    2014-09-01

    Chrysotherapeutics are under investigation as new or additional treatments for different types of cancers. In this study, gold complexes were investigated for their anticancer potential using Raman spectroscopy. The aim of the study was to determine whether Raman spectroscopy could be used for the characterization of metallodrug-induced cell death. Symptoms of cell death such as decreased peak intensities of proteins bonds and phosphodiester bonds found in deoxyribose nucleic acids were evident in the principal component analysis of the spectra. Vibrational bands around 761 cm-1 and 1300 cm-1 (tryptophan, ethanolamine group, and phosphatidylethanolamine) and 1720 cm-1 (ester bonds associated with phospholipids) appeared in the Raman spectra of cervical adenocarcinoma (HeLa) cells after metallodrug treatment. The significantly (p treatment could be a molecular signature of induced apoptosis since both the co-regulated phosphatidylserine and phosphatidylethanolamine are externalized during cell death. Treated cells had significantly higher levels of glucose and glycogen vibrational peaks, indicative of a survival mechanism of cancer cells under chemical stress. Cancer cells excrete chemotherapeutics to improve their chances of survival and utilize glucose to achieve this. Raman spectroscopy was able to monitor a survival strategy of cancer cells in the form of glucose uptake to alleviate chemical stress. Raman spectroscopy was invaluable in obtaining molecular information generated by biomolecules affected by anticancer metallodrug treatments and presents an alternative to less reproducible, conventional biochemical assays for cytotoxicity analyses.

  1. Oxygen cycling to improve survival of stem cells for myocardial repair: A review.

    Science.gov (United States)

    Dall, Christopher; Khan, Mahmood; Chen, Chun-An; Angelos, Mark G

    2016-05-15

    Heart disease represents the leading cause of death among Americans. There is currently no clinical treatment to regenerate viable myocardium following myocardial infarction, and patients may suffer progressive deterioration and decreased myocardial function from the effects of remodeling of the necrotic myocardium. New therapeutic strategies hold promise for patients who suffer from ischemic heart disease by directly addressing the restoration of functional myocardium following death of cardiomyocytes. Therapeutic stem cell transplantation has shown modest benefit in clinical human trials with decreased fibrosis and increased functional myocardium. Moreover, autologous transplantation holds the potential to implement these therapies while avoiding the immunomodulation concerns of heart transplantation. Despite these benefits, stem cell therapy has been characterized by poor survival and low engraftment of injected stem cells. The hypoxic tissue environment of the ischemic/infracting myocardium impedes stem cell survival and engraftment in myocardial tissue. Hypoxic preconditioning has been suggested as a viable strategy to increase hypoxic tolerance of stem cells. A number of in vivo and in vitro studies have demonstrated improved stem cell viability by altering stem cell secretion of protein signals and up-regulation of numerous paracrine signaling pathways that affect inflammatory, survival, and angiogenic signaling pathways. This review will discuss both the mechanisms of hypoxic preconditioning as well as the effects of hypoxic preconditioning in different cell and animal models, examining the pitfalls in current research and the next steps into potentially implementing this methodology in clinical research trials. PMID:27091653

  2. The epidemiology and survival of extrapulmonary small cell carcinoma in South East England, 1970–2004

    International Nuclear Information System (INIS)

    Extrapulmonary small cell carcinoma (EPSCC) is a rare cancer and few studies describe its epidemiology. Our objectives were to compare the incidence and survival of EPSCC in South East England with small cell carcinoma of the lung (SCLC), to determine the most common anatomical presenting sites for EPSCC and to compare survival in EPSCC by disease stage and site of diagnosis. We used data from the Thames Cancer Registry database for South East England between 1970 and 2004 to determine the incidence, most common anatomical sites, and survival by site, and stage of EPSCC. 1618 patients registered with EPSCC were identified. We calculated the age-standardised incidence rate for EPSCC using the European standard population and compared this to that for SCLC. We calculated survival using the Kaplan-Meier method for EPSCC and SCLC, and reported 3-year survival for different EPSCC anatomical sites and disease stages. The incidence of EPSCC was much lower than for SCLC, similar in males and females, and stable throughout the study period, with incidence rates of 0.45 per 100,000 in males and 0.37 in females during 2000–2004. In general, patients with EPSCC had a better 3-year survival (19%) than SCLC (5%). The most common anatomical sites for EPSCC were oesophagus (18%), other gastrointestinal (15%), genitourinary (20%), head and neck (11%), and breast (10%). Breast EPSCC had the best 3-year survival (60%) and gastrointestinal EPSCC the worst (7%). This study suggests that EPSCC has a stable incidence and confirms that it presents widely, but most commonly in the oesophagus and breast. Site and extent of disease influence survival, with breast EPSCC having the best prognosis. Further studies using standardised diagnosis, prospective case registers for uncommon diseases and European cancer registries are needed to understand this disease

  3. 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.

  4. Correlation Between Fuhrman Nuclear Grade and Stage with Survival in Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Evrim KUŞ

    2009-09-01

    Full Text Available Objective: Our aim was to find out the correlation between histopathological findings and survival of patients with renal cell carcinoma.Material and Method: We examined 114 cases diagnosed as renal cell carcinoma at the Pathology Department in 1997 - 2007. We explored the correlation of histological type, size, Fuhrman nuclear grade, renal capsule invasion, renal vein and lymphatic/vascular invasion, tumoral necrosis and stage with survival.Results: Histological subtypes were determined as clear cell in 101 cases (88,6% , papillary in 9 cases (7,9%, and chromophobe renal cell carcinoma in 4 cases (3,5%. Reliable follow-up data were available in 96 of 114 cases. 74 of them (77,1% were alive and 22 of them (22,9% had died related to renal cell carcinoma. The mean follow-up time was 21,5 months with a wide range between 2 days and 87 months. 5 year survival was 61,3 months, and its probability was 58,2%.Conclusion: We provide statistical results compatible with the recent literature in regard to high Fuhrman nuclear grade, advanced stage, necrosis, capsule invasion, microvascular invasion and lymph node invasion decreasing the survival time.

  5. Influence of preirradiational and postirradiational heating of lyophilized Micrococcus radioproteolyticus cells on their survival

    International Nuclear Information System (INIS)

    The survival curve of Micrococcus radioproteolyticus following gamma irradiation of lyophilized cells is characterized by a broad shoulder reaching as far as the dose range 10 - 20 kGy (1 - 2 Mrad). The course of the curve indicates that under these conditions most of the changes induced by irradiation have the character of sublethal damage, which the cell can repair. The course of the survival curve does not change if the lyophilized cells are heated prior to irradiation for 2 h at 60 0C. Certain changes do occur if the preirradiational temperature is 80 0C. If the cells are exposed to increased temperature after irradiation even a temperature of 60 0C brings about a marked decrease in survival. A temperature of 80 0C after irradiation leads to extensive changes in the shape of survival curves, which are characterized by a narrowing or even disappearing of the shoulders. It can be concluded from the results obtained that an increased temperature modifies the capability of irradiated lyophilized cells to repair radiation damage. (author)

  6. Differential survival of solitary and aggregated bacterial cells promotes aggregate formation on leaf surfaces

    Science.gov (United States)

    Monier, J.-M.; Lindow, S. E.

    2003-01-01

    The survival of individual Pseudomonas syringae cells was determined on bean leaf surfaces maintained under humid conditions or periodically exposed to desiccation stress. Cells of P. syringae strain B728a harboring a GFP marker gene were visualized by epifluorescence microscopy, either directly in situ or after recovery from leaves, and dead cells were identified as those that were stained with propidium iodide in such populations. Under moist, conducive conditions on plants, the proportion of total live cells was always high, irrespective of their aggregated state. In contrast, the proportion of the total cells that remained alive on leaves that were periodically exposed to desiccation stress decreased through time and was only ≈15% after 5 days. However, the fraction of cells in large aggregates that were alive on such plants in both condition was much higher than more solitary cells. Immediately after inoculation, cells were randomly distributed over the leaf surface and no aggregates were observed. However, a very aggregated pattern of colonization was apparent within 7 days, and >90% of the living cells were located in aggregates of 100 cells or more. Our results strongly suggest that, although conducive conditions favor aggregate formation, such cells are much more capable of tolerating environmental stresses, and the preferential survival of cells in aggregates promotes a highly clustered spatial distribution of bacteria on leaf surfaces. PMID:14665692

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

    Science.gov (United States)

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

    2016-01-01

    A signaling molecule which is involved in proliferation and migration of malignant cells is the lipid mediator sphingosine-1-phosphate (S1P). There are hints for a potential role of S1P signaling in malignant brain tumors such as glioblastoma multiforme (GBM) which is characterized by a poor prognosis. Therefore, a comprehensive expression analysis of S1P receptors (S1P1-S1P5) and S1P metabolizing enzymes in human GBM (n = 117) compared to healthy brain (n = 10) was performed to evaluate their role for patient's survival. Furthermore, influence of S1P receptor inhibition on proliferation and migration were studied in LN18 GBM cells. Compared to control brain, mRNA levels of S1P1, S1P2, S1P3 and S1P generating sphingosine kinase-1 were elevated in GBM. Kaplan-Meier analyses demonstrated an association between S1P1 and S1P2 with patient's survival times. In vitro, an inhibitory effect of the SphK inhibitor SKI-II on viability of LN18 cells was shown. S1P itself had no effect on viability but stimulated LN18 migration which was blocked by inhibition of S1P1 and S1P2. The participation of S1P1 and S1P2 in LN18 migration was further supported by siRNA-mediated silencing of these receptors. Immunoblots and inhibition experiments suggest an involvement of the PI3-kinase/AKT1 pathway in the chemotactic effect of S1P in LN18 cells. In summary, our data argue for a role of S1P signaling in proliferation and migration of GBM cells. Individual components of the S1P pathway represent prognostic factors for patients with GBM. Perspectively, a selective modulation of S1P receptor subtypes could represent a therapeutic approach for GBM patients and requires further evaluation. PMID:26887055

  8. Survival among patients with advanced renal cell carcinoma in the pretargeted versus targeted therapy eras.

    Science.gov (United States)

    Li, Pengxiang; Wong, Yu-Ning; Armstrong, Katrina; Haas, Naomi; Subedi, Prasun; Davis-Cerone, Margaret; Doshi, Jalpa A

    2016-02-01

    Between December 2005 and October 2009, FDA approved six targeted therapies shown to significantly extend survival for advanced renal cell carcinoma (RCC) patients in clinical trials. This study aimed to examine changes in survival between the pretargeted and targeted therapy periods in advanced RCC patients in a real-world setting. Utilizing the 2000-2010 SEER Research files, a pre-post study design with a contemporaneous comparison group was employed to examine differences in survival outcomes for patients diagnosed with advanced RCC (study group) or advanced prostate cancer (comparison group, for whom no significant treatment innovations happened during this period) across the pretargeted therapy era (2000-2005) and the targeted therapy era (2006-2010). RCC patients diagnosed in the targeted therapy era (N = 6439) showed improved survival compared to those diagnosed in the pretargeted therapy era (N = 7231, hazard ratio (HR) for all-cause death: 0.86, P < 0.01), while the change between the pre-post periods was not significant for advanced prostate cancer patients (HR: 0.97, P = 0.08). Advanced RCC patients had significantly larger improvements in overall survival compared to advanced prostate cancer patients (z = 4.31; P < 0.01). More detailed year-to-year analysis revealed greater survival improvements for RCC in the later years of the posttargeted period. Similar results were seen for cause-specific survival. Subgroup analyses by nephrectomy status, age, and gender showed consistent findings. Patients diagnosed with advanced RCC during the targeted therapy era had better survival outcomes than those diagnosed during the pretargeted therapy era. Future studies should examine the real-world survival improvements directly associated with targeted therapies. PMID:26645975

  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 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...... / propidium iodide assays). RESULTS: We found higher expression of P2X7R protein in PDAC compared to HPDE cells. P2X7R had notable disparate effects on PDAC survival. Firstly, high concentrations of ATP or the specific P2X7R agonist, BzATP, had cytotoxic effects in all cell lines, and cell death was mediated...

  10. IL17 producing γδT cells induce angiogenesis and are associated with poor survival in gallbladder cancer patients.

    Science.gov (United States)

    Sudam Patil, Rushikesh; Umesh Shah, Sagar; Vinayak Shrikhande, Shailesh; Goel, Mahesh; Prabhakar Dikshit, Rajesh; Vivek Chiplunkar, Shubhada

    2016-08-15

    Despite conventional treatment modalities, gallbladder cancer (GBC) remains a highly lethal malignancy. Prognostic biomarkers and effective adjuvant immunotherapy for GBC are not available. In the recent past, immunotherapeutic approaches targeting tumor associated inflammation have gained importance but the mediators of inflammatory circuit remain unexplored in GBC patients. In the current prospective study, we investigated the role of IL17 producing TCRγδ(+) (Tγδ17), CD4(+) (Th17), CD8(+) (Tc17) and regulatory T cells (Tregs) in pathogenesis of GBC. Analysis by multi-color flow cytometry revealed that compared to healthy individuals (HI), Tγδ17, Th17 and Tc17 cells were increased in peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TIL) of GBC patients. Tregs were decreased in PBMCs but increased in TILs of GBC patients. The suppressive potential of Tregs from GBC patients and HI were comparable. Serum cytokines profile of GBC patients showed elevated levels of cytokines (IL6, IL23 and IL1β) required for polarization and/or stabilization of IL17 producing cells. We demonstrated that Tγδ17 cells migrate toward tumor bed using CXCL9-CXCR3 axis. IL17 secreted by Tγδ17 induced productions of vascular endothelial growth factor and other angiogenesis related factors in GBC cells. Tγδ17 cells promote vasculogenesis as studied by chick chorioallantoic membrane assay. Survival analysis showed that Tγδ17, Th17 and Treg cells in peripheral blood were associated with poor survival of GBC patients. Our findings suggest that Tγδ17 is a protumorigenic subtype of γδT cells which induces angiogenesis. Tγδ17 may be considered as a predictive biomarker in GBC thus opening avenues for targeted therapies. PMID:27062572

  11. Targeted disruption of the LAMA3 gene in mice reveals abnormalities in survival and late stage differentiation of epithelial cells.

    Science.gov (United States)

    Ryan, M C; Lee, K; Miyashita, Y; Carter, W G

    1999-06-14

    Laminin 5 regulates anchorage and motility of epithelial cells through integrins alpha6beta4 and alpha3beta1, respectively. We used targeted disruption of the LAMA3 gene, which encodes the alpha3 subunit of laminin 5 and other isoforms, to examine developmental functions that are regulated by adhesion to the basement membrane (BM). In homozygous null animals, profound epithelial abnormalities were detected that resulted in neonatal lethality, consistent with removal of all alpha3-laminin isoforms from epithelial BMs. Alterations in three different cellular functions were identified. First, using a novel tissue adhesion assay, we found that the mutant BM could not induce stable adhesion by integrin alpha6beta4, consistent with the presence of junctional blisters and abnormal hemidesmosomes. In the absence of laminin 5 function, we were able to detect a new ligand for integrin alpha3beta1 in the epidermal BM, suggesting that basal keratinocytes can utilize integrin alpha3beta1 to interact with an alternative ligand. Second, we identified a survival defect in mutant epithelial cells that could be rescued by exogenous laminin 5, collagen, or an antibody against integrin alpha6beta4, suggesting that signaling through beta1 or beta4 integrins is sufficient for survival. Third, we detected abnormalities in ameloblast differentiation in developing mutant incisors indicating that events downstream of adhesion are affected in mutant animals. These results indicate that laminin 5 has an important role in regulating tissue organization, gene expression, and survival of epithelium. PMID:10366601

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells in irradiated bone marrow cell culture in vitro

    International Nuclear Information System (INIS)

    Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells after irradiation were studied in the long-term culture of mouse bone marrow cells in vitro. No difference was observed in the survival of the stem cells among cultures in which 0 - 107 cells were re-inoculated on the adherent cell colonies in the culture flask. Stem cells showed a significant proliferation within 1 week and the number of the stem cells exceeded the control in 3 weeks after irradiation in the cultures with less than 106 re-inoculated cells per flask. In contrast, there was a considerable delay in the onset of stem cell proliferation after irradiation in the culture with 107 cells per flask. Based on these results, a possibility that a stimulator of stem cell proliferation, released from irradiated stromal cells, is cancelled by an inhibitory factor produced by irradiated or unirradiated haemopoietic cells is postulated. (author)

  14. Tumor cells with low proteasome subunit expression predict overall survival in head and neck cancer patients

    International Nuclear Information System (INIS)

    Experimental and clinical data suggest that solid cancers contain treatment-resistant cancer stem cells that will impair treatment efficacy. The objective of this study was to investigate if head and neck squamous cell carcinoma (HNSCC) also contain cancer stem cells that can be identified by low 26S proteasome activity and if their presence correlates to clinical outcome. Human HNSCC cells, engineered to report lack of proteasome activity based on accumulation of a fluorescent fusion protein, were separated based on high (ZsGreen-cODCneg) or low (ZsGreen-cODCpos) proteasome activity. Self-renewal capacity, tumorigenicity and radioresistance were assessed. Proteasome subunit expression was analyzed in tissue microarrays and correlated to survival and locoregional cancer control of 174 patients with HNSCC. HNSCC cells with low proteasome activity showed a significantly higher self-renewal capacity and increased tumorigenicity. Irradiation enriched for ZsGreen-cODCpos cells. The survival probability of 82 patients treated with definitive radio- or chemo-radiotherapy exhibiting weak, intermediate, or strong proteasome subunit expression were 21.2, 28.8 and 43.8 months (p = 0.05), respectively. Locoregional cancer control was comparably affected. Subpopulations of HNSCC display stem cell features that affect patients’ tumor control and survival. Evaluating cancer tissue for expression of the proteasome subunit PSMD1 may help identify patients at risk for relapse

  15. Late radiation response of kidney assayed by tubule-cell survival

    International Nuclear Information System (INIS)

    An assay for the survival of renal tubule cells was developed using mice, analogous to other in-situ clonogenic cell survival assays. One kidney was irradiated using a 137Cs irradiator and removed 60-68 weeks later for histological examination. In unirradiated animals there were about 370 tubules in contact with the capsule in a coronal cross section at the middle of the kidney. After irradiation, extensive tubular damage was the dominant lesion. The number of epithelialised tubules in contact with the capsule showed a dose-dependent logarithmic decline. The dose-survival relationship for the clonogenic cells responsible for the regeneration of tubule epithelium was described by a D0 value of 1.5 Gy over the dose range 11-16 Gy. This radiosensitivity resembles that of stem cells in acutely responding tissues. The lack of histological evidence of damage to the arterial vasculature at the time the tubules are initially denuded of epithelium, and the similarity of renal tubule cell radiosensitivity to that of other mammalian cells, support the hypothesis that ''late'' radiation injury results primarily from depletion of parenchymal cells, not indirectly from injury to blood vessels, as has been the prevailing belief. (author)

  16. ATG7 regulates energy metabolism, differentiation and survival of Philadelphia-chromosome-positive cells.

    Science.gov (United States)

    Karvela, Maria; Baquero, Pablo; Kuntz, Elodie M; Mukhopadhyay, Arunima; Mitchell, Rebecca; Allan, Elaine K; Chan, Edmond; Kranc, Kamil R; Calabretta, Bruno; Salomoni, Paolo; Gottlieb, Eyal; Holyoake, Tessa L; Helgason, G Vignir

    2016-06-01

    A major drawback of tyrosine kinase inhibitor (TKI) treatment in chronic myeloid leukemia (CML) is that primitive CML cells are able to survive TKI-mediated BCR-ABL inhibition, leading to disease persistence in patients. Investigation of strategies aiming to inhibit alternative survival pathways in CML is therefore critical. We have previously shown that a nonspecific pharmacological inhibition of autophagy potentiates TKI-induced death in Philadelphia chromosome-positive cells. Here we provide further understanding of how specific and pharmacological autophagy inhibition affects nonmitochondrial and mitochondrial energy metabolism and reactive oxygen species (ROS)-mediated differentiation of CML cells and highlight ATG7 (a critical component of the LC3 conjugation system) as a potential specific therapeutic target. By combining extra- and intracellular steady state metabolite measurements by liquid chromatography-mass spectrometry with metabolic flux assays using labeled glucose and functional assays, we demonstrate that knockdown of ATG7 results in decreased glycolysis and increased flux of labeled carbons through the mitochondrial tricarboxylic acid cycle. This leads to increased oxidative phosphorylation and mitochondrial ROS accumulation. Furthermore, following ROS accumulation, CML cells, including primary CML CD34(+) progenitor cells, differentiate toward the erythroid lineage. Finally, ATG7 knockdown sensitizes CML progenitor cells to TKI-induced death, without affecting survival of normal cells, suggesting that specific inhibitors of ATG7 in combination with TKI would provide a novel therapeutic approach for CML patients exhibiting persistent disease. PMID:27168493

  17. 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. PMID:18824601

  18. 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.

  19. STAT3 signaling pathway is necessary for cell survival and tumorsphere forming capacity in ALDH{sup +}/CD133{sup +} stem cell-like human colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Li, E-mail: lin.796@osu.edu [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States); Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030 (China); Fuchs, James; Li, Chenglong [Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210 (United States); Olson, Veronica [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States); Bekaii-Saab, Tanios [Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43210 (United States); Lin, Jiayuh, E-mail: lin.674@osu.edu [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells. Black-Right-Pointing-Pointer STAT3 inhibitor, FLLL32 inhibits P-STAT3 and STAT3 target genes in colon cancer stem-like cells. Black-Right-Pointing-Pointer Inhibition of STAT3 resulted in decreased cell viability and reduced numbers of tumorspheres. Black-Right-Pointing-Pointer STAT3 is required for survival and tumorsphere forming capacity in colon cancer stem-like cells. Black-Right-Pointing-Pointer Targeting STAT3 in cancer stem-like cells may offer a novel treatment approach for colon cancer. -- Abstract: Persistent activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in colon cancer. Increasing evidence suggests the existence of a small population of colon cancer stem or cancer-initiating cells may be responsible for tumor initiation, metastasis, and resistance to chemotherapy and radiation. Whether STAT3 plays a role in colon cancer-initiating cells and the effect of STAT3 inhibition is still unknown. Flow cytometry was used to isolate colon cancer stem-like cells from three independent human colon cancer cell lines characterized by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulation (ALDH{sup +}/CD133{sup +}). The effects of STAT3 inhibition in colon cancer stem-like cells were examined. The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells and was reduced by a STAT3-selective small molecular inhibitor, FLLL32. FLLL32 also inhibited the expression of potential STAT3 downstream target genes in colon cancer stem-like cells including survivin, Bcl-XL, as well as Notch-1, -3, and -4, which may be involved in stem cell function. Furthermore, FLLL32 inhibited cell viability and tumorsphere formation as well as induced cleaved caspase-3 in colon cancer stem-like cells. FLLL32 is more potent than curcumin as evidenced with lower

  20. STAT3 signaling pathway is necessary for cell survival and tumorsphere forming capacity in ALDH+/CD133+ stem cell-like human colon cancer cells

    International Nuclear Information System (INIS)

    Highlights: ► The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells. ► STAT3 inhibitor, FLLL32 inhibits P-STAT3 and STAT3 target genes in colon cancer stem-like cells. ► Inhibition of STAT3 resulted in decreased cell viability and reduced numbers of tumorspheres. ► STAT3 is required for survival and tumorsphere forming capacity in colon cancer stem-like cells. ► Targeting STAT3 in cancer stem-like cells may offer a novel treatment approach for colon cancer. -- Abstract: Persistent activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in colon cancer. Increasing evidence suggests the existence of a small population of colon cancer stem or cancer-initiating cells may be responsible for tumor initiation, metastasis, and resistance to chemotherapy and radiation. Whether STAT3 plays a role in colon cancer-initiating cells and the effect of STAT3 inhibition is still unknown. Flow cytometry was used to isolate colon cancer stem-like cells from three independent human colon cancer cell lines characterized by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulation (ALDH+/CD133+). The effects of STAT3 inhibition in colon cancer stem-like cells were examined. The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells and was reduced by a STAT3-selective small molecular inhibitor, FLLL32. FLLL32 also inhibited the expression of potential STAT3 downstream target genes in colon cancer stem-like cells including survivin, Bcl-XL, as well as Notch-1, -3, and -4, which may be involved in stem cell function. Furthermore, FLLL32 inhibited cell viability and tumorsphere formation as well as induced cleaved caspase-3 in colon cancer stem-like cells. FLLL32 is more potent than curcumin as evidenced with lower IC50 in colon cancer stem-like cells. In summary, our results indicate that STAT3 is a novel therapeutic target in colon cancer stem

  1. The effect of caffeine and adenine on radiation induced suppression of DNA synthesis, and cell survival

    International Nuclear Information System (INIS)

    Exposure of cultured mammalian cells to ionizing radiation or UV light results in a transient decrease in the rate of DNA synthesis. This depression in synthetic rate may be attenuated or deferred via a post-irradiation treatment with caffeine or adenine. It has been suggested that this attenuation may increase the fixation of damage and, therefore, increase radiation sensitivity. However, it has been previously reported that, for V79 cells treated with caffeine or adenine, no correlation exists between the extent of depression and cell survival. The present investigation expands upon these findings by examining the effect of caffeine or adenine post-irradiation treatment on two cell lines with normal UV sensitivity, mouse 3T3 and CHO AA8 cells, and one UV sensitive cell line, CHO UV5 cells. Both caffeine and adenine have been found to reduce, or delay, the suppression in DNA synthesis in all three cell lines. Surprisingly, caffeine appeared to induced even the UV5 cells to recover DNA synthetic ability. The amount of reduction in suppression of DNA synthesis, however, varies between the different cell lines and no consistent relationship with cell survival has emerged

  2. Dormancy of cancer cells with suppression of AKT activity contributes to survival in chronic hypoxia.

    Directory of Open Access Journals (Sweden)

    Hiroko Endo

    Full Text Available A hypoxic microenvironment in tumors has been recognized as a cause of malignancy or resistance to various cancer therapies. In contrast to recent progress in understanding the acute response of cancer cells to hypoxia, the characteristics of tumor cells in chronic hypoxia remain elusive. We have identified a pancreatic cancer cell line, AsPC-1, that is exceptionally able to survive for weeks under 1% oxygen conditions while most tested cancer cell lines die after only some days under these conditions. In chronic hypoxia, AsPC-1 cells entered a state of dormancy characterized by no proliferation, no death, and metabolic suppression. They reversibly switched to active status after being placed again in optimal culture conditions. ATP turnover, an indicator of energy demand, was markedly decreased and accompanied by reduced AKT phosphorylation. Forced activation of AKT resulted in increased ATP turnover and massive cell death in vitro and a decreased number of dormant cells in vivo. In contrast to most cancer cell lines, primary-cultured colorectal cancer cells easily entered the dormant status with AKT suppression under hypoxia combined with growth factor-depleted conditions. Primary colorectal cancer cells in dormancy were resistant to chemotherapy. Thus, the ability to survive in a deteriorated microenvironment by entering into dormancy under chronic hypoxia might be a common property among cancer cells. Targeting the regulatory mechanism inducing this dormant status could provide a new strategy for treating cancer.

  3. Aberrant Expression of Functional BAFF-System Receptors by Malignant B-Cell Precursors Impacts Leukemia Cell Survival

    OpenAIRE

    Maia, Sara; Pelletier, Marc; Ding, Jixin; Hsu, Yen-Ming; Rao, Sambasiva P.; Cardoso, Angelo A.; Sallan, Stephen Earl; Nadler, Lee Marshall

    2011-01-01

    Despite exhibiting oncogenic events, patient's leukemia cells are responsive and dependent on signals from their malignant bone marrow (BM) microenvironment, which modulate their survival, cell cycle progression, trafficking and resistance to chemotherapy. Identification of the signaling pathways mediating this leukemia/microenvironment interplay is critical for the development of novel molecular targeted therapies. We observed that primary leukemia B-cell precursors aberrantly express recept...

  4. Radiation survival of two human cervical carcinoma cell lines after multifraction irradiation

    International Nuclear Information System (INIS)

    Purpose: Multifraction irradiation may contribute to radiation therapy treatment failure if selection of radiation resistant subpopulations occurs. We sought to determine whether surviving cells following daily fraction irradiation of two human cervical squamous cell carcinoma lines would express different radiation survival characteristics compared to the unirradiated parent. Methods and Materials: A late-passage line (HTB35) and an early-passage line (RECA) received daily 2 Gy x-irradiation. Two new stable HTB35 cell lines were established after 40 and 60 Gy (HTB35-40 and HTB35-60). A single line was established from RECA after 30 Gy (RECA-30). High dose rate (74 cGy/min) acute radiation survival curves were prepared from the three new lines and the unirradiated parents. Potentially lethal damage repair (PLDR) and sublethal damage repair (SLDR) responses were detailed for HTB35, HTB35-40 and HTB35-60. Low dose rate (1.27 cGy/min) survival was measured for HTB35 and HTB35-60. Clones were derived from HTB35 and from HTB35-60 and the surviving fraction at 2 Gy (SF2) values were determined. Results: The two parent lines (HTB35 and RECA) differed in acute radiation survival. The surviving lines following multifraction irradiation (HTB35-40, HTB35-60, and RECA-30) showed no change in acute radiation response compared to the appropriate parent. HTB35-40 and HTB35-60 were repair proficient, demonstrating similar PLDR and SLDR recovery ratios as the parent. Likewise, acute, low dose rate survival of HTB35 and HTB35-60 was similar. Nine clones derived from HTB35 lacked a consistent difference in SF2 compared to the original culture. A single clone of seven derived from HTB35-60 was consistently radiation resistant (SF2 = 0.81 ± 0.06) compared to the original culture (SF2 = 0.50 ± 0.09). Conclusion: No evidence was obtained that cell lines generated following multiple daily fractions of x-irradiation in vitro possessed acute radiation survival or repair characteristics

  5. 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

  6. Lung cancer survival in England: trends in non-small-cell lung cancer survival over the duration of the National Lung Cancer Audit

    OpenAIRE

    Khakwani, A; Rich, A L; Powell, H A; Tata, L J; Stanley, R A; Baldwin, D R; Duffy, J P; Hubbard , R B

    2013-01-01

    Background: In comparison with other European and North American countries, England has poor survival figures for lung cancer. Our aim was to evaluate the changes in survival since the introduction of the National Lung Cancer Audit (NLCA). Methods: We used data from the NLCA to identify people with non-small-cell lung cancer (NSCLC) and stratified people according to their performance status (PS) and clinical stage. Using Cox regression, we calculated hazard ratios (HRs) for death according t...

  7. HIV-1 and recombinant gp120 affect the survival and differentiation of human vessel wall-derived mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Pasquinelli Gianandrea

    2011-05-01

    Full Text Available Abstract Background HIV infection elicits the onset of a progressive immunodeficiency and also damages several other organs and tissues such as the CNS, kidney, heart, blood vessels, adipose tissue and bone. In particular, HIV infection has been related to an increased incidence of cardiovascular diseases and derangement in the structure of blood vessels in the absence of classical risk factors. The recent characterization of multipotent mesenchymal cells in the vascular wall, involved in regulating cellular homeostasis, suggests that these cells may be considered a target of HIV pathogenesis. This paper investigated the interaction between HIV-1 and vascular wall resident human mesenchymal stem cells (MSCs. Results MSCs were challenged with classical R5 and X4 HIV-1 laboratory strains demonstrating that these strains are able to enter and integrate their retro-transcribed proviral DNA in the host cell genome. Subsequent experiments indicated that HIV-1 strains and recombinant gp120 elicited a reliable increase in apoptosis in sub-confluent MSCs. Since vascular wall MSCs are multipotent cells that may be differentiated towards several cell lineages, we challenged HIV-1 strains and gp120 on MSCs differentiated to adipogenesis and endotheliogenesis. Our experiments showed that the adipogenesis is increased especially by upregulated PPARγ activity whereas the endothelial differentiation induced by VEGF treatment was impaired with a downregulation of endothelial markers such as vWF, Flt-1 and KDR expression. These viral effects in MSC survival and adipogenic or endothelial differentiation were tackled by CD4 blockade suggesting an important role of CD4/gp120 interaction in this context. Conclusions The HIV-related derangement of MSC survival and differentiation may suggest a direct role of HIV infection and gp120 in impaired vessel homeostasis and in genesis of vessel damage observed in HIV-infected patients.

  8. N-methyl-D-aspartate promotes the survival of cerebellar granule cells: pharmacological characterization

    DEFF Research Database (Denmark)

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

    1989-01-01

    The survival of cerebellar granule cells in culture is promoted by chronic exposure to N-methyl-D-aspartate (NMDA). The effect is due to the stimulation of 'conventional' NMDA receptor-ionophore complex: it is concentration dependent, voltage dependent and blocked by the selective antagonists D-2...

  9. 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...

  10. A biophysical model applied to survival of tumor cells and chromosomal aberrations in human lymphocytes

    International Nuclear Information System (INIS)

    Investigations on survival of tumor cells E.M.T.6 and chromosomal aberrations in human lymphocytes irradiated in vitro and microdosimetric studies were made using a helion beam. The results obtained were compared in order to see if the Dual Radiation Action Theory of ROSSI and KELLERER can explain these radiobiological phenomena

  11. Nicotine-mediated signals modulate cell death and survival of T lymphocytes

    International Nuclear Information System (INIS)

    The capacity of nicotine to affect the behavior of non-neuronal cells through neuronal nicotinic acetylcholine receptors (nAChRs) has been the subject of considerable recent attention. Previously, we showed that exposure to nicotine activates the nuclear factor of activated T cells (NFAT) transcription factor in lymphocytes and endothelial cells, leading to alterations in cellular growth and vascular endothelial growth factor production. Here, we extend these studies to document effects of nicotine on lymphocyte survival. The data show that nicotine induces paradoxical effects that might alternatively enforce survival or trigger apoptosis, suggesting that depending on timing and context, nicotine might act both as a survival factor or as an inducer of apoptosis in normal or transformed lymphocytes, and possibly other non-neuronal cells. In addition, our results show that, while having overlapping functions, low and high affinity nAChRs also transmit signals that promote distinct outcomes in lymphocytes. The sum of our data suggests that selective modulation of nAChRs might be useful to regulate lymphocyte activation and survival in health and disease.

  12. Prolonged survival of virulent Treponema pallidum (Nichols strain) in cell-free and tissue culture systems.

    Science.gov (United States)

    Fieldsteel, A H; Becker, F A; Stout, J G

    1977-10-01

    Survival of Treponema pallidum was found to be prolonged in the presence of tissue culture. Of the 12 cultures studied, cottontail rabbit epithelium (Sf1Ep) supported T. pallidum for the longest time. In horizontal Leighton tubes with reduced medium and an atmosphere of 5% CO2 in N2, the 50% survival time (ST50) was 5 to 6 days for treponemes associated with monolayers of Sf1Ep cells. Comparable cell-free tubes had ST50 values of less than 4 days. In vertical Leighton tubes containing 6 ml of prereduced medium incubated aerobically, gradients of O2 tension and redox potential were established. Attachment and survival of T. pallidum were greatest at a depth of about 10 to 20 mm. Motility was between 70 and 95% in this area throughout the first 14 days of incubation. Occasionally, greater than 50% motility was observed for as long as 21 days. The redox potential and O2 tension in the optimal area of gradient cultures were reproduced by adjusting the medium depth in a shell vial culture system containing cells on a horizontal cover slip. Treponemes associated with the cell monolayer in both gradient and shell vial cultures were still virulent after 21 days in vitro. The dilution of testis extract and the concentration of T. pallidum were found to be important factors in survival of T. pallidum. PMID:332639

  13. 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

    Abstract Objective. The aim of this study was to evaluate overall survival (OS) after treatment of metastatic renal cell carcinoma (mRCC) following the introduction of tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin (mTOR) inhibitors. Material and methods. One-hundred and fort...

  14. TNF-α promotes cell survival through stimulation of K+ channel and NFκB activity in corneal epithelial cells

    International Nuclear Information System (INIS)

    Tumor necrosis factor (TNF-α) in various cell types induces either cell death or mitogenesis through different signaling pathways. In the present study, we determined in human corneal epithelial cells how TNF-α also promotes cell survival. Human corneal epithelial (HCE) cells were cultured in DMEM/F-12 medium containing 10% FBS. TNF-α stimulation induced activation of a voltage-gated K+ channel detected by measuring single channel activity using patch clamp techniques. The effect of TNF-α on downstream events included NFκB nuclear translocation and increases in DNA binding activities, but did not elicit ERK, JNK, or p38 limb signaling activation. TNF-α induced increases in p21 expression resulting in partial cell cycle attenuation in the G1 phase. Cell cycle progression was also mapped by flow cytometer analysis. Blockade of TNF-α-induced K+ channel activity effectively prevented NFκB nuclear translocation and binding to DNA, diminishing the cell-survival protective effect of TNF-α. In conclusion, TNF-α promotes survival of HCE cells through sequential stimulation of K+ channel and NFκB activities. This response to TNF-α is dependent on stimulating K+ channel activity because following suppression of K+ channel activity TNF-α failed to activate NFκB nuclear translocation and binding to nuclear DNA

  15. Neurorestorative Role of Stem Cells in Alzheimer's Disease: Astrocyte Involvement.

    Science.gov (United States)

    Choi, Sung S; Lee, Sang-Rae; Lee, Hong J

    2016-01-01

    Neurogenesis is maintained in both neonatal and adult brain, although it is dramatically reduced in aged neurogenic brain region such as the subgranular layer and subventricular zone of the dentate gyrus (DG). Astrocytes play important roles for survival and maintenance of neurons as well as maintenance of neurogenic niche in quiescent state. Aβ can induce astrocyte activation which give rise to produce reactive oxygen species (ROS) and cytotoxic cytokines and chemokines, and subsequently induce neuronal death. Unfortunately, the current therapeutic medicines have been limited to reduce the symptoms and delay the pathogenesis of Alzheimer's disease (AD), but not to cure it. Stem cells enhance neurogenesis and Aβ clearing as well as improved cognitive impairment. Neurotrophins and growth factors which are produced from both stem cells and astrocytes also have neuroprotective effects via neurogenesis. Secreted factors from both astrocytes and neural stem cells also are influenced in neurogenesis and neuron survival in neurodegenerative diseases. Transplanted stem cells overexpressing neurogenic factors may be an effective and therapeutic tool to enhance neurogenesis for AD. PMID:27018261

  16. Regulation of normal B-cell differentiation and malignant B-cell survival by OCT2.

    Science.gov (United States)

    Hodson, Daniel J; Shaffer, Arthur L; Xiao, Wenming; Wright, George W; Schmitz, Roland; Phelan, James D; Yang, Yandan; Webster, Daniel E; Rui, Lixin; Kohlhammer, Holger; Nakagawa, Masao; Waldmann, Thomas A; Staudt, Louis M

    2016-04-01

    The requirement for the B-cell transcription factor OCT2 (octamer-binding protein 2, encoded by Pou2f2) in germinal center B cells has proved controversial. Here, we report that germinal center B cells are formed normally after depletion of OCT2 in a conditional knockout mouse, but their proliferation is reduced and in vivo differentiation to antibody-secreting plasma cells is blocked. This finding led us to examine the role of OCT2 in germinal center-derived lymphomas. shRNA knockdown showed that almost all diffuse large B-cell lymphoma (DLBCL) cell lines are addicted to the expression of OCT2 and its coactivator OCA-B. Genome-wide chromatin immunoprecipitation (ChIP) analysis and gene-expression profiling revealed the broad transcriptional program regulated by OCT2 that includes the expression of STAT3, IL-10, ELL2, XBP1, MYC, TERT, and ADA. Importantly, genetic alteration of OCT2 is not a requirement for cellular addiction in DLBCL. However, we detected amplifications of the POU2F2 locus in DLBCL tumor biopsies and a recurrent mutation of threonine 223 in the DNA-binding domain of OCT2. This neomorphic mutation subtly alters the DNA-binding preference of OCT2, leading to the transactivation of noncanonical target genes including HIF1a and FCRL3 Finally, by introducing mutations designed to disrupt the OCT2-OCA-B interface, we reveal a requirement for this protein-protein interface that ultimately might be exploited therapeutically. Our findings, combined with the predominantly B-cell-restricted expression of OCT2 and the absence of a systemic phenotype in our knockout mice, suggest that an OCT2-targeted therapeutic strategy would be efficacious in both major subtypes of DLBCL while avoiding systemic toxicity. PMID:26993806

  17. Increased cell survival by inhibition of BRCA1 using an antisense approach in an estrogen responsive ovarian carcinoma cell line

    International Nuclear Information System (INIS)

    We tested the hypothesis that BRCA1 may play a role in the regulation of ovarian tumor cell death as well as the inhibition of ovarian cell proliferation. Introduction of BRCA1 antisense retroviral constructs into BG-1 estrogen-dependent ovarian adenocarcinoma cells resulted in reduced BRCA1 expression. BRCA1 antisense pooled populations and derived subclones were able to proliferate in monolayer culture without estrogen, whereas control cells began to die after 10 days of estrogen deprivation. In addition, both populations and subclones of BRCA1 antisense infected cells demonstrated a growth advantage in monolayer culture in the presence of estrogen and were able to proliferate in monolayer culture without estrogen, while control cells did not. Furthermore, clonal studies demonstrated that reduced levels of BRCA1 protein correlated with growth in soft agar and greater tumor formation in nude mice in the absence of estrogen. These data suggest that reduction of BRCA1 protein in BG-1 ovarian adenocarcinoma cells may have an effect on cell survival during estrogen deprivation both in vitro and in vivo. Germline mutations in the breast and ovarian cancer susceptibility gene BRCA1, which is located on chromosome 17q21, are associated with a predisposition to the development of cancer in these organs [1,2]. No mutations in the BRCA1 gene have been detected in sporadic breast cancer cases, but mutations have been detected in sporadic cases of ovarian cancer [3,4]. Although there is debate regarding the level of cancer risk associated with mutations in BRCA1 and the significance of the lack of mutations in sporadic tumors, it is possible that alterations in the function of BRCA1 may occur by mechanisms other than mutation, leading to an underestimation of risk when it is calculated solely on the basis of mutational analysis. Such alterations cannot be identified until the function and regulation of BRCA1 are better understood. The BRCA1 gene encodes a 220-kDa nuclear

  18. Gender-Dependent Survival of Allogeneic Trophoblast Stem Cells in Liver

    OpenAIRE

    Epple-Farmer, Jessica; Debeb, Bisrat G.; Smithies, Oliver; Binas, Bert

    2009-01-01

    In view of the well-known phenomenon of trophoblast immune privilege, trophoblast stem cells (TSCs) might be expected to be immune privileged, which could be of interest for cell or gene therapies. Yet in the ectopic sites tested so far, TSC transplants fail to show noticeable immune privilege and seem to lack physiological support. However, we show here that after portal venous injection, green fluorescent protein (GFP)-labeled TSCs survive for several months in the livers of allogeneic fema...

  19. Ascorbic acid improves embryonic cardiomyoblast cell survival and promotes vascularization in potential myocardial grafts in vivo

    OpenAIRE

    Martinez, E. C.; Wang, J; Gan, S U; Singh, R.; Lee, C. N.; Kofidis, T

    2010-01-01

    Organ restoration via cell therapy and tissue transplantation is limited by impaired graft survival. We tested the hypothesis that ascorbic acid (AA) reduces cell death in myocardial grafts both in vitro and in vivo and introduced a new model of autologous graft vascularization for later transplantation. Luciferase (Fluc)- and green fluorescent protein (GFP)-expressing H9C2 cardiomyoblasts were seeded in gelatin scaffolds to form myocardial artificial grafts (MAGs). MAGs were supplemented wit...

  20. Survival and DNA repair in ultraviolet-irradiated haploid and diploid cultured frog cells

    International Nuclear Information System (INIS)

    Survival and repair of DNA following ultraviolet (254-nm) radiation have been investigated in ICR 2A, a cultured cell line from haploid embryos of the grassfrog, Rana pipiens. Survival curves from cells recovering in the dark gave mean lethal dose value (D0) in the range 1.5-1.7 Jm-2 for both haploid and diploid cell stocks. The only significant difference observed between haploids and diploids was in the extent of the shoulder at low fluence (Dsub(q)), the value for exponentially multiplying diploid cells (3.0 Jm-2) being higher than that found for haploids (1.2 Jm-2). Irradiation of cultures reversibly blocked in the G1 phase of the cell cycle gave survival-curve coefficients indistinguishable between haploids and diploids. Post-irradiation exposure to visible light restored colony-forming capacity and removed chromatographically estimated pyrimidine dimers from DNA at the same rates. After fluences killing 90% of the cells, complete restoration of survival was obtained after 60-min exposure to 500 foot-candles, indicating that in this range lethality is entirely photoreversible and therefore attributable to pyrimidine dimers in DNA. Dimer removal required illumination following ultraviolet exposure, intact cells and physiological temperature, implying that the photoreversal involved DNA photolyase activity. Excision-repair capacity was slight, since no loss of dimers could be detected chromoatographically during up to 48 h incubation in the dark and since autoradiographically detected 'unscheduled DNA synthesis' was limited to a 2-fold increase saturated at 10 Jm-2. These properties make ICR 2A frog cells useful to explore how DNA-repair pathways influence mutant yield. (Auth.)

  1. Carnitine palmitoyltransferase 1C promotes cell survival and tumor growth under conditions of metabolic stress

    OpenAIRE

    Zaugg, K; Yao, Y.; Reilly, P T; K. Kannan; Kiarash, R; Mason, J.; Huang, P.; Sawyer, S K; Fuerth, B.; Faubert, B; Kalliomäki, T; Elia, A J; Luo, X.; Nadeem, V; Bungard, D

    2011-01-01

    Tumor cells gain a survival/growth advantage by adapting their metabolism to respond to environmental stress, a process known as metabolic transformation. The best-known aspect of metabolic transformation is the Warburg effect, whereby cancer cells up-regulate glycolysis under aerobic conditions. However, other mechanisms mediating metabolic transformation remain undefined. Here we report that carnitine palmitoyltransferase 1C (CPT1C), a brain-specific metabolic enzyme, may participate in met...

  2. Acute lymphoblastic leukemia cells that survive combination chemotherapy in vivo remain sensitive to allogeneic immune effects

    OpenAIRE

    Jansson, Johan; Hsu, Yu-Chiao; Kuzin, Igor I.; Campbell, Andrew; Mullen, Craig A.

    2010-01-01

    Allogeneic hematopoietic stem cell transplantation is often performed for patients with acute lymphoblastic leukemia (ALL) whose disease has relapsed after chemotherapy treatment. However, graft versus leukemia (GVL) effects in ALL are generally weak and the mechanisms of this weakness are unknown. These studies tested the hypothesis that ALL cells that have survived conventional chemotherapy in vivo acquire relative resistance to the allogeneic GVL effect. C57BL/6 mice were injected with mur...

  3. UBIAD1-mediated vitamin K2 synthesis is required for vascular endothelial cell survival and development

    OpenAIRE

    Hegarty, Jeffrey M.; Yang, Hongbo; Chi, Neil C.

    2013-01-01

    Multi-organ animals, such as vertebrates, require the development of a closed vascular system to ensure the delivery of nutrients to, and the transport of waste from, their organs. As a result, an organized vascular network that is optimal for tissue perfusion is created through not only the generation of new blood vessels but also the remodeling and maintenance of endothelial cells via apoptotic and cell survival pathways. Here, we show that UBIAD1, a vitamin K2/menaquinone-4 biosynthetic en...

  4. Genomic instability induced by 137Cs γ-ray irradiation in CHL surviving cells

    International Nuclear Information System (INIS)

    Objective: To study in parallel several possible manifestations of instability of surviving CHL cells after irradiation, namely the frequencies of mutation at locus, micronuclei and apoptosis. Methods: The frequencies of mutation at HGPRT locus, micronuclei and apoptosis were assayed at various times in surviving cells irradiated with γ-rays. Results: The surviving cells showed a persistently increased frequency of mutation at the HGPRT locus after irradiation until 53 days. Mutant fraction as high as 10-4 was scored, tens of times higher than those assayed in control cells studied in parallel. The frequency of bi nucleated cells with micronuclei determined within 24 hours after irradiation increased with dose and reached a peak value of (26.58 +- 2.48)% at 3 Gy, decreasing at higher doses to a plateau around 20%. The micronucleus frequency decreased steeply to about (14.47 +- 2.39)% within the first 3 days post-irradiation, and fluctuated at around 10% up to 56 days post-irradiation. The delayed efficiency of irradiated cells was significantly decreased. The frequency of apoptosis peaked about (24.90 +- 4.72)% at 10 Gy 48 h post-irradiation (γ-ray dose between 3-10 Gy) and then decreased to about 12% within 3 days. It was significantly higher than in control cells until 14 days. Conclusions: It shows that genomic instability induced by radiation can be transmitted to the progeny of surviving cells and may take many forms of expression such as lethal mutation, chromosome aberrations, gene mutation, etc

  5. Radiation survival of cells from spheroids grown in different oxygen concentrations

    International Nuclear Information System (INIS)

    The position of the internal, chronically hypoxic cells in spheroids was varied by alterations in the oxygen concentration in the growth medium. Such alterations were expected to cause large changes in the size of the radiobiologically hypoxic fraction. This was tested by growing and irradiating spheroids in oxygen concentrations between 5 and 20.3%, ensuring that the irradiation and growth conditions were as similar as possible. The survival curves appeared to be linear below a surviving fraction of 3 x 10-2, and the slopes were intermediate between the slopes of control curves for cells from spheroids irradiated in nitrogen or when fully oxygenated. Thus direct estimates of the hypoxic fractions could not be made. Two models of oxygen diffusion might explain the data. One model assumes that a large fraction of cells was fully hypoxic (radiobiologically) and that these internal, G1-confined, chronically hypoxic cells had a lower inherent radioresistance than the outer proliferating cells. Evidence was presented which indicated that this model was unlikely to be correct. The other model assumes that the inherent radioresistance was equal throughout the spheroid, and that the innermost cells died before the oxygen concentration was reduced sufficiently to cause full hypoxic protection. Theoretical survival curves based on this model were generated using the measured geometries ofthe spheroids and multitarget single-hit survival theory. Acceptable agreement with the postulate that the innermost cells of spheroids die at between 0.2 and 0.4% oxygen was obtained. These data may have implications regarding the relative contributions of chronic and acute hypoxia to the fraction of hypoxic cells in tumors

  6. Stem Cell Derived Extracellular Matrix Enables Survival and Multi Lineage Differentiation within Superporous Hydrogels

    OpenAIRE

    Köllmer, Melanie; Keskar, Vandana; Hauk, Thomas G.; Collins, John M.; Russell, Brenda; Gemeinhart, Richard A.

    2012-01-01

    Hydrophilic poly(ethylene glycol) diacrylate (PEGDA) hydrogel surfaces resist protein adsorption and are generally thought to be unsuitable for anchorage dependent cells to adhere. Intriguingly, our previous findings revealed that PEGDA superporous hydrogel scaffolds (SPHs) allow anchorage of bone marrow derived human mesenchymal stem cells (hMSCs) and support their long term survival. Therefore, we hypothesized that the physicochemical characteristics of the scaffold impart properties that c...

  7. Pancreatic β-cells activate a JunB/ATF3-dependent survival pathway during inflammation

    DEFF Research Database (Denmark)

    Gurzov, E N; Barthson, J; Marhfour, I;

    2012-01-01

    Destruction of insulin-producing pancreatic β-cells by local autoimmune inflammation is a hallmark of type 1 diabetes. Histochemical analysis of pancreases from non-obese diabetic mice indicated activation of the transcription factor JunB/AP-1 (activator protein-1) after autoimmune infiltration of...... primary β-cells and human islet cells against pro-inflammatory mediators. These results were confirmed in genetically modified islets derived from Ubi-JunB transgenic mice. Our findings identify ATF3 as a novel downstream target of JunB in the survival mechanism of β-cells under inflammatory stress....

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

    OpenAIRE

    Khairnar, Vishal; Duhan, Vikas; Maney, Sathish Kumar; Honke, Nadine; Shaabani, Namir; Pandyra, Aleksandra A; Seifert, Marc; Pozdeev, Vitaly; Xu, Haifeng C.; Sharma, Piyush; Baldin, Fabian; Marquardsen, Florian; Merches, Katja; Lang, Elisabeth; Kirschning, Carsten

    2015-01-01

    B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1 −/− mice limits...

  9. The role of physical rehabilitation in stem cell transplantation patients.

    Science.gov (United States)

    Steinberg, Amir; Asher, Arash; Bailey, Charlotte; Fu, Jack B

    2015-08-01

    The purpose of this paper is to review the evidence for the role of physical rehabilitation in stem cell transplantation patients. We will also review the literature and discuss professional experiences on how rehabilitation can play a role in stem cell transplant care and survivorship. Hematopoietic stem cell transplantation (HCT) is a procedure that has evolved substantially over the years to help treat multiple conditions, particularly hematologic malignancies. HCT can be very stressful on the body and can leave patients weakened and sometimes quite debilitated. Supportive care measures have advanced to improve the quality of life and overall survival of HCT survivors. One key component of improved supportive care is gaining increased attention, and that is physical medicine and rehabilitation. Its role in HCT survivorship care is expanding, and new insight and research within the discipline have focused on fatigue, inflammation, exercise, and the development of structured rehabilitation programs to improve the musculoskeletal sequelae of transplantation. This literature review has demonstrated the utility of physical rehabilitation in HCT, its impact on cancer-related fatigue, and to outline the current state of the literature on these topics. The paper delves into a background of HCT. Cancer-related fatigue in HCT is then discussed and summarized, and the role that exercise plays in modifying such fatigue is outlined. We then outline the models and the impact that physical rehabilitation may play in HCT recipients. PMID:25971213

  10. 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.

  11. Mga is essential for the survival of pluripotent cells during peri-implantation development.

    Science.gov (United States)

    Washkowitz, Andrew J; Schall, Caroline; Zhang, Kun; Wurst, Wolfgang; Floss, Thomas; Mager, Jesse; Papaioannou, Virginia E

    2015-01-01

    The maintenance and control of pluripotency is of great interest in stem cell biology. The dual specificity T-box/basic-helix-loop-helix-zipper transcription factor Mga is expressed in the pluripotent cells of the inner cell mass (ICM) and epiblast of the peri-implantation mouse embryo, but its function has not been investigated previously. Here, we use a loss-of-function allele and RNA knockdown to demonstrate that Mga depletion leads to the death of proliferating pluripotent ICM cells in vivo and in vitro, and the death of embryonic stem cells (ESCs) in vitro. Additionally, quiescent pluripotent cells lacking Mga are lost during embryonic diapause. Expression of Odc1, the rate-limiting enzyme in the conversion of ornithine into putrescine in the synthesis of polyamines, is reduced in Mga mutant cells, and the survival of mutant ICM cells as well as ESCs is rescued in culture by the addition of exogenous putrescine. These results suggest a mechanism whereby Mga influences pluripotent cell survival through regulation of the polyamine pool in pluripotent cells of the embryo, whether they are in a proliferative or quiescent state. PMID:25516968

  12. 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.

  13. Factors that contribute to long-term survival in patients with leukemia not in remission at allogeneic hematopoietic cell transplantation

    Directory of Open Access Journals (Sweden)

    Okamura Hiroshi

    2011-04-01

    Full Text Available Abstract Background There has been insufficient examination of the factors affecting long-term survival of more than 5 years in patients with leukemia that is not in remission at transplantation. Method We retrospectively analyzed leukemia not in remission at allogeneic hematopoietic cell transplantation (allo-HCT performed at our institution between January 1999 and July 2009. Forty-two patients with a median age of 39 years received intensified conditioning (n = 9, standard (n = 12 or reduced-intensity conditioning (n = 21 for allo-HCT. Fourteen patients received individual chemotherapy for cytoreduction during the three weeks prior to reduced-intensity conditioning. Diagnoses comprised acute leukemia (n = 29, chronic myeloid leukemia-accelerated phase (n = 2, myelodysplastic syndrome/acute myeloid leukemia (MDS/AML (n = 10 and plasma cell leukemia (n = 1. In those with acute leukemia, cytogenetic abnormalities were intermediate (44% or poor (56%. The median number of blast cells in bone marrow (BM was 26.0% (range; 0.2-100 before the start of chemotherapy for allo-HCT. Six patients had leukemic involvement of the central nervous system. Stem cell sources were related BM (7%, related peripheral blood (31%, unrelated BM (48% and unrelated cord blood (CB (14%. Results Engraftment was achieved in 33 (79% of 42 patients. Median time to engraftment was 17 days (range: 9-32. At five years, the cumulative probabilities of acute graft-versus-host disease (GVHD and chronic GVHD were 63% and 37%, respectively. With a median follow-up of 85 months for surviving patients, the five-year Kaplan-Meier estimates of leukemia-free survival rate and overall survival (OS were 17% and 19%, respectively. At five years, the cumulative probability of non-relapse mortality was 38%. In the univariable analyses of the influence of pre-transplant variables on OS, poor-risk cytogenetics, number of BM blasts (>26%, MDS overt AML and CB as stem cell source were

  14. 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. PMID:24305165

  15. Hypoxic preconditioning of mesenchymal stromal cells induces metabolic changes, enhances survival, and promotes cell retention in vivo.

    Science.gov (United States)

    Beegle, Julie; Lakatos, Kinga; Kalomoiris, Stefanos; Stewart, Heather; Isseroff, R Rivkah; Nolta, Jan A; Fierro, Fernando A

    2015-06-01

    Mesenchymal stem cells/multipotent stromal cells (MSCs) are promising therapeutics for a variety of conditions. However, after transplantation, cell retention remains extremely challenging. Given that many hypoxic signals are transitory and that the therapeutic administration of MSCs is typically into tissues that are normally hypoxic, we studied the effect of hypoxic preconditioning (HP) prior to new exposure to hypoxia. We show that preincubation for 2 days or more in 1% oxygen reduces serum deprivation-mediated cell death, as observed by higher cell numbers and lower incorporation of EthD-III and Annexin V. Consistently, HP-MSCs expressed significantly lower levels of cytochrome c and heme oxygenase 1 as compared to controls. Most importantly, HP-MSCs showed enhanced survival in vivo after intramuscular injection into immune deficient NOD/SCID-IL2Rgamma(-/-) mice. Interestingly, HP-MSCs consume glucose and secrete lactate at a slower rate than controls, possibly promoting cell survival, as glucose remains available to the cells for longer periods of time. In addition, we compared the metabolome of HP-MSCs to controls, before and after hypoxia and serum deprivation, and identified several possible mediators for HP-mediated cell survival. Overall, our findings suggest that preincubation of MSCs for 2 days or more in hypoxia induces metabolic changes that yield higher retention after transplantation. PMID:25702874

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

    Science.gov (United States)

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

    2015-05-01

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

  17. 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.

  18. QHREDGS enhances tube formation, metabolism and survival of endothelial cells in collagen-chitosan hydrogels.

    Directory of Open Access Journals (Sweden)

    Jason W Miklas

    Full Text Available Cell survival in complex, vascularized tissues, has been implicated as a major bottleneck in advancement of therapies based on cardiac tissue engineering. This limitation motivates the search for small, inexpensive molecules that would simultaneously be cardio-protective and vasculogenic. Here, we present peptide sequence QHREDGS, based upon the fibrinogen-like domain of angiopoietin-1, as a prime candidate molecule. We demonstrated previously that QHREDGS improved cardiomyocyte metabolism and mitigated serum starved apoptosis. In this paper we further demonstrate the potency of QHREDGS in its ability to enhance endothelial cell survival, metabolism and tube formation. When endothelial cells were exposed to the soluble form of QHREDGS, improvements in endothelial cell barrier functionality, nitric oxide production and cell metabolism (ATP levels in serum starved conditions were found. The functionality of the peptide was then examined when conjugated to collagen-chitosan hydrogel, a potential carrier for in vivo application. The presence of the peptide in the hydrogel mitigated paclitaxel induced apoptosis of endothelial cells in a dose dependent manner. Furthermore, the peptide modified hydrogels stimulated tube-like structure formation of encapsulated endothelial cells. When integrin αvβ3 or α5β1 were antibody blocked during cell encapsulation in peptide modified hydrogels, tube formation was abolished. Therefore, the dual protective nature of the novel peptide QHREDGS may position this peptide as an appealing augmentation for collagen-chitosan hydrogels that could be used for biomaterial delivered cell therapies in the settings of myocardial infarction.

  19. QHREDGS enhances tube formation, metabolism and survival of endothelial cells in collagen-chitosan hydrogels.

    Science.gov (United States)

    Miklas, Jason W; Dallabrida, Susan M; Reis, Lewis A; Ismail, Nesreen; Rupnick, Maria; Radisic, Milica

    2013-01-01

    Cell survival in complex, vascularized tissues, has been implicated as a major bottleneck in advancement of therapies based on cardiac tissue engineering. This limitation motivates the search for small, inexpensive molecules that would simultaneously be cardio-protective and vasculogenic. Here, we present peptide sequence QHREDGS, based upon the fibrinogen-like domain of angiopoietin-1, as a prime candidate molecule. We demonstrated previously that QHREDGS improved cardiomyocyte metabolism and mitigated serum starved apoptosis. In this paper we further demonstrate the potency of QHREDGS in its ability to enhance endothelial cell survival, metabolism and tube formation. When endothelial cells were exposed to the soluble form of QHREDGS, improvements in endothelial cell barrier functionality, nitric oxide production and cell metabolism (ATP levels) in serum starved conditions were found. The functionality of the peptide was then examined when conjugated to collagen-chitosan hydrogel, a potential carrier for in vivo application. The presence of the peptide in the hydrogel mitigated paclitaxel induced apoptosis of endothelial cells in a dose dependent manner. Furthermore, the peptide modified hydrogels stimulated tube-like structure formation of encapsulated endothelial cells. When integrin αvβ3 or α5β1 were antibody blocked during cell encapsulation in peptide modified hydrogels, tube formation was abolished. Therefore, the dual protective nature of the novel peptide QHREDGS may position this peptide as an appealing augmentation for collagen-chitosan hydrogels that could be used for biomaterial delivered cell therapies in the settings of myocardial infarction. PMID:24013716

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

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    International Nuclear Information System (INIS)

    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 H2O2 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 H2O2 levels while maintaining viability/mitochondrial function. Osteocalcin also significantly improved glucose stimulated insulin secretion and insulin content in rat islets after 48 h of high glucose exposure compared to untreated islets. As expected sustained high glucose down-regulated gene/protein expression of INS1 and BCL2 while increasing TXNIP expression. Interestingly, osteocalcin treatment reversed the effects of high glucose on gene/protein expression. We conclude that osteocalcin can protect beta cells from the negative effects of glucose-induced oxidative stress, in part, by reducing TXNIP expression, thereby preserving beta cell function and survival. - Highlights: • Osteocalcin reduces glucose-induced oxidative stress in beta cells. • Osteocalcin preserves beta cell function and survival under stress conditions. • Osteocalcin reduces glucose-induced TXNIP expression

  2. Cell survival and growth delay in rat R-1 tumours after radiation and vinblastine treatment

    International Nuclear Information System (INIS)

    The rat R-1 rhabdomyosarcoma with a capacity for colony growth in vitro after excision of the tumour and dissociation by a trypsin method was used to investigate the effectiveness of radio-chemotherapy. Growth delay data were compared with data on survival of cells derived from tumours treated in situ. An excess in growth delay was observed when vinblastine (1.5 mg/kg) was given at intervals of 0.3 to 2 d after or 4 d before a dose of 20 Gy of X-rays. Cell survival data indicated that the maximum effectiveness of the drug treatment and the combined treatment (vinblastine and a dose of 10 Gy) can be assessed 2 to 3 d after treatment. The fractions of surviving cells determined after combined therapy at 0,1 and 2 d intervals were not significantly different from the fractions expected on the basis of simple multiplication of the fractions surviving individual treatments. The data suggested that the excess in tumour growth delay observed cannot be accounted for by co-operative interaction of the doses of radiation and drug. (author)

  3. CCR9 interactions support ovarian cancer cell survival and resistance to cisplatin-induced apoptosis in a PI3K-dependent and FAK-independent fashion

    Directory of Open Access Journals (Sweden)

    Johnson Erica L

    2010-06-01

    Full Text Available Abstract Background Cisplatin is more often used to treat ovarian cancer (OvCa, which provides modest survival advantage primarily due to chemo-resistance and up regulated anti-apoptotic machineries in OvCa cells. Therefore, targeting the mechanisms responsible for cisplatin resistance in OvCa cell may improve therapeutic outcomes. We have shown that ovarian cancer cells express CC chemokine receptor-9 (CCR9. Others have also shown that CCL25, the only natural ligand for CCR9, up regulates anti-apoptotic proteins in immature T lymphocytes. Hence, it is plausible that CCR9-mediated cell signals might be involved in OvCa cell survival and inhibition of cisplatin-induced apoptosis. In this study, we investigated the potential role and molecular mechanisms of CCR9-mediated inhibition of cisplatin-induced apoptosis in OvCa cells. Methods Cell proliferation, vibrant apoptosis, and TUNEL assays were performed with or without cisplatin treatment in presence or absence of CCL25 to determine the role of the CCR9-CCL25 axis in cisplatin resistance. In situ Fast Activated cell-based ELISA (FACE assays were performed to determine anti-apoptotic signaling molecules responsible for CCL25-CCR9 mediated survival. Results Our results show interactions between CCR9 and CCL25 increased anti-apoptotic signaling cascades in OvCa cells, which rescued cells from cisplatin-induced cell death. Specifically, CCL25-CCR9 interactions mediated Akt, activation as well as GSK-3β and FKHR phosphorylation in a PI3K-dependent and FAK-independent fashion. Conclusions Our results suggest the CCR9-CCL25 axis plays an important role in reducing cisplatin-induced apoptosis of OvCa cells.

  4. An osteoblast-derived proteinase controls tumor cell survival via TGF-beta activation in the bone microenvironment.

    Directory of Open Access Journals (Sweden)

    Sophie Thiolloy

    Full Text Available Breast to bone metastases frequently induce a "vicious cycle" in which osteoclast mediated bone resorption and proteolysis results in the release of bone matrix sequestered factors that drive tumor growth. While osteoclasts express numerous proteinases, analysis of human breast to bone metastases unexpectedly revealed that bone forming osteoblasts were consistently positive for the proteinase, MMP-2. Given the role of MMP-2 in extracellular matrix degradation and growth factor/cytokine processing, we tested whether osteoblast derived MMP-2 contributed to the vicious cycle of tumor progression in the bone microenvironment.To test our hypothesis, we utilized murine models of the osteolytic tumor-bone microenvironment in immunocompetent wild type and MMP-2 null mice. In longitudinal studies, we found that host MMP-2 significantly contributed to tumor progression in bone by protecting against apoptosis and promoting cancer cell survival (caspase-3; immunohistochemistry. Our data also indicate that host MMP-2 contributes to tumor induced osteolysis (μCT, histomorphometry. Further ex vivo/in vitro experiments with wild type and MMP-2 null osteoclast and osteoblast cultures identified that 1 the absence of MMP-2 did not have a deleterious effect on osteoclast function (cd11B isolation, osteoclast differentiation, transwell migration and dentin resorption assay; and 2 that osteoblast derived MMP-2 promoted tumor survival by regulating the bioavailability of TGFβ, a factor critical for cell-cell communication in the bone (ELISA, immunoblot assay, clonal and soft agar assays.Collectively, these studies identify a novel "mini-vicious cycle" between the osteoblast and metastatic cancer cells that is key for initial tumor survival in the bone microenvironment. In conclusion, the findings of our study suggest that the targeted inhibition of MMP-2 and/or TGFβ would be beneficial for the treatment of bone metastases.

  5. DNA damage and repair in relation to mammalian cell survival implications for microdosimetry

    International Nuclear Information System (INIS)

    The number and dose dependence of DSBs, measured with greatly improved precision in mammalian cells, are in accord with the Chadwick-Leenhouts model and suggest that approximately one DSB per cell causes reproductive death. The rate and activation energy for SSB repair agree with those measured for the critical sublesion by studies of survival at low dose rate. The data indicate that SSBs may interact in the cell to yield a DSB at up to approximately 250 base pairs separation. These findings may provide a basis for bringing the theory of dual radiation action, the Chadwick-Leenhouts molecular model, and survival and stand break measurements into mutual agreement, a development which may greatly benefit the study of radiobiology, and particularly of microdosimetry

  6. 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.

  7. Activated H-Ras regulates hematopoietic cell survival by modulating Survivin

    International Nuclear Information System (INIS)

    Survivin expression and Ras activation are regulated by hematopoietic growth factors. We investigated whether activated Ras could circumvent growth factor-regulated Survivin expression and if a Ras/Survivin axis mediates growth factor independent survival and proliferation in hematopoietic cells. Survivin expression is up-regulated by IL-3 in Ba/F3 and CD34+ cells and inhibited by the Ras inhibitor, farnesylthiosalicylic acid. Over-expression of constitutively activated H-Ras (CA-Ras) in Ba/F3 cells blocked down-modulation of Survivin expression, G0/G1 arrest, and apoptosis induced by IL-3 withdrawal, while dominant-negative (DN) H-Ras down-regulated Survivin. Survivin disruption by DN T34A Survivin blocked CA-Ras-induced IL-3-independent cell survival and proliferation; however, it did not affect CA-Ras-mediated enhancement of S-phase, indicating that the anti-apoptotic activity of CA-Ras is Survivin dependent while its S-phase enhancing effect is not. These results indicate that CA-Ras modulates Survivin expression independent of hematopoietic growth factors and that a CA-Ras/Survivin axis regulates survival and proliferation of transformed hematopoietic cells

  8. Inhibition of PI3K/BMX Cell Survival Pathway Sensitizes to BH3 Mimetics in SCLC.

    Science.gov (United States)

    Potter, Danielle S; Galvin, Melanie; Brown, Stewart; Lallo, Alice; Hodgkinson, Cassandra L; Blackhall, Fiona; Morrow, Christopher J; Dive, Caroline

    2016-06-01

    Most small cell lung cancer (SCLC) patients are initially responsive to cytotoxic chemotherapy, but almost all undergo fatal relapse with progressive disease, highlighting an urgent need for improved therapies and better patient outcomes in this disease. The proapoptotic BH3 mimetic ABT-737 that targets BCL-2 family proteins demonstrated good single-agent efficacy in preclinical SCLC models. However, so far clinical trials of the BH3 mimetic Navitoclax have been disappointing. We previously demonstrated that inhibition of a PI3K/BMX cell survival signaling pathway sensitized colorectal cancer cells to ABT-737. Here, we show that SCLC cell lines, which express high levels of BMX, become sensitized to ABT-737 upon inhibition of PI3K in vitro, and this is dependent on inhibition of the PI3K-BMX-AKT/mTOR signaling pathway. Consistent with these cell line data, when combined with Navitoclax, PI3K inhibition suppressed tumor growth in both an established SCLC xenograft model and in a newly established circulating tumor cell-derived explant (CDX) model generated from a blood sample obtained at presentation from a chemorefractory SCLC patient. These data show for the first time that a PI3K/BMX signaling pathway plays a role in SCLC cell survival and that a BH3 mimetic plus PI3K inhibition causes prolonged tumor regression in a chemorefractory SCLC patient-derived model in vivo These data add to a body of evidence that this combination should move toward the clinic. Mol Cancer Ther; 15(6); 1248-60. ©2016 AACR. PMID:27197306

  9. The M1 form of tumor-associated macrophages in non-small cell lung cancer is positively associated with survival time

    International Nuclear Information System (INIS)

    Tumor-associated macrophages (TAMs) play an important role in growth, progression and metastasis of tumors. In non-small cell lung cancer (NSCLC), TAMs' anti-tumor or pro-tumor role is not determined. Macrophages are polarized into M1 (with anti-tumor function) and M2 (with pro-tumor function) forms. This study was conducted to determine whether the M1 and M2 macrophage densities in NSCLC are associated with patient's survival time. Fifty patients with an average of 1-year survival (short survival group) and 50 patients with an average of 5-year survival (long survival group) were included in this retrospective study. Paraffin-embedded NSCLC specimens and their clinicopathological data including up to 8-year follow-up information were used. Immunohistochemical double-staining of CD68/HLA-DR (markers for M1 macrophages) and CD68/CD163 (markers for M2 macrophages) was performed and evaluated in a blinded fashion. The M1 and M2 macrophage densities in the tumor islets, stroma, or islets and stroma were determined using computer-aided microscopy. Correlation of the macrophage densities and patient's survival time was analyzed using the Statistical Package for the Social Sciences. Approximately 70% of TAMs were M2 macrophages and the remaining 30% were M1 macrophages in NSCLC. The M2 macrophage densities (approximately 78 to 113 per mm2) in the tumor islets, stroma, or islets and stroma were not significantly different between the long survival and short survival groups. The M1 macrophage densities in the tumor islets (approximately 70/mm2) and stroma (approximately 34/mm2) of the long survival group were significantly higher than the M1 macrophage densities in the tumor islets (approximately 7/mm2) and stroma (13/mm2) of the short survival group (P < 0.001 and P < 0.05, respectively). The M2 macrophage densities were not associated with patient's survival time. The M1 macrophage densities in the tumor islets, stroma, or islets and stroma were

  10. Private manufacturing SMEs survival and growth in Vietnam: The role of export participation

    OpenAIRE

    Vu, Huong

    2012-01-01

    This study investigates for the first time a linkage between export participation and firm performance in terms of survival and profit growth in Vietnam. Using an unbalanced panel dataset from 2005 to 2009, our study shows no difference in the survival probability between exporters and non-exporters. By digging deeper to export status at different stages, the results indicate that continuous exporters have a positive association with probability of survival whereas export stoppers indicate a ...

  11. The effect of comorbidity on stage-specific survival in resected non-small cell lung cancer patients

    DEFF Research Database (Denmark)

    Lüchtenborg, Margreet; Jakobsen, Erik; Krasnik, Mark; Linklater, Karen M; Mellemgaard, Anders; Møller, Henrik

    2012-01-01

    To quantify the effect of comorbidity on stage-specific survival in resected non-small cell lung cancer (NSCLC) patients.......To quantify the effect of comorbidity on stage-specific survival in resected non-small cell lung cancer (NSCLC) patients....

  12. PCA3 noncoding RNA is involved in the control of prostate-cancer cell survival and modulates androgen receptor signaling

    International Nuclear Information System (INIS)

    PCA3 is a non-coding RNA (ncRNA) that is highly expressed in prostate cancer (PCa) cells, but its functional role is unknown. To investigate its putative function in PCa biology, we used gene expression knockdown by small interference RNA, and also analyzed its involvement in androgen receptor (AR) signaling. LNCaP and PC3 cells were used as in vitro models for these functional assays, and three different siRNA sequences were specifically designed to target PCA3 exon 4. Transfected cells were analyzed by real-time qRT-PCR and cell growth, viability, and apoptosis assays. Associations between PCA3 and the androgen-receptor (AR) signaling pathway were investigated by treating LNCaP cells with 100 nM dihydrotestosterone (DHT) and with its antagonist (flutamide), and analyzing the expression of some AR-modulated genes (TMPRSS2, NDRG1, GREB1, PSA, AR, FGF8, CdK1, CdK2 and PMEPA1). PCA3 expression levels were investigated in different cell compartments by using differential centrifugation and qRT-PCR. LNCaP siPCA3-transfected cells significantly inhibited cell growth and viability, and increased the proportion of cells in the sub G0/G1 phase of the cell cycle and the percentage of pyknotic nuclei, compared to those transfected with scramble siRNA (siSCr)-transfected cells. DHT-treated LNCaP cells induced a significant upregulation of PCA3 expression, which was reversed by flutamide. In siPCA3/LNCaP-transfected cells, the expression of AR target genes was downregulated compared to siSCr-transfected cells. The siPCA3 transfection also counteracted DHT stimulatory effects on the AR signaling cascade, significantly downregulating expression of the AR target gene. Analysis of PCA3 expression in different cell compartments provided evidence that the main functional roles of PCA3 occur in the nuclei and microsomal cell fractions. Our findings suggest that the ncRNA PCA3 is involved in the control of PCa cell survival, in part through modulating AR signaling, which may raise new

  13. PCA3 noncoding RNA is involved in the control of prostate-cancer cell survival and modulates androgen receptor signaling

    Directory of Open Access Journals (Sweden)

    Ferreira Luciana Bueno

    2012-11-01

    Full Text Available Abstract Background PCA3 is a non-coding RNA (ncRNA that is highly expressed in prostate cancer (PCa cells, but its functional role is unknown. To investigate its putative function in PCa biology, we used gene expression knockdown by small interference RNA, and also analyzed its involvement in androgen receptor (AR signaling. Methods LNCaP and PC3 cells were used as in vitro models for these functional assays, and three different siRNA sequences were specifically designed to target PCA3 exon 4. Transfected cells were analyzed by real-time qRT-PCR and cell growth, viability, and apoptosis assays. Associations between PCA3 and the androgen-receptor (AR signaling pathway were investigated by treating LNCaP cells with 100 nM dihydrotestosterone (DHT and with its antagonist (flutamide, and analyzing the expression of some AR-modulated genes (TMPRSS2, NDRG1, GREB1, PSA, AR, FGF8, CdK1, CdK2 and PMEPA1. PCA3 expression levels were investigated in different cell compartments by using differential centrifugation and qRT-PCR. Results LNCaP siPCA3-transfected cells significantly inhibited cell growth and viability, and increased the proportion of cells in the sub G0/G1 phase of the cell cycle and the percentage of pyknotic nuclei, compared to those transfected with scramble siRNA (siSCr-transfected cells. DHT-treated LNCaP cells induced a significant upregulation of PCA3 expression, which was reversed by flutamide. In siPCA3/LNCaP-transfected cells, the expression of AR target genes was downregulated compared to siSCr-transfected cells. The siPCA3 transfection also counteracted DHT stimulatory effects on the AR signaling cascade, significantly downregulating expression of the AR target gene. Analysis of PCA3 expression in different cell compartments provided evidence that the main functional roles of PCA3 occur in the nuclei and microsomal cell fractions. Conclusions Our findings suggest that the ncRNA PCA3 is involved in the control of PCa cell survival

  14. 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. PMID:26864431

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

    International Nuclear Information System (INIS)

    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. 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. 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 HT29 and SW620 express higher levels of a splice variant of

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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

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

    International Nuclear Information System (INIS)

    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

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

    Directory of Open Access Journals (Sweden)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Survival-related DNA repair phenomena in cultured rat-kangaroo cells

    International Nuclear Information System (INIS)

    Cultured cells (line PtK-2) from the marsupial mammal rat-kangaroo, or potoroo (Potorous tridactylis), which photoreactivate (PR) both UV-induced dimers and lethality, excise few dimers, and are only slightly sensitized by post-UV exposure to caffeine, were subjected to caffeine and hydroxyurea (HU) treatments during the 30-min PR period. It was found that neither caffeine nor HU inhibited PR of lethality as measured by colony-forming ability. Further, the cells exhibited no photoprotective properties and 3 mM caffeine potentiated the same slight survival decrease in both photoreactivated and unphotoreactivated cells

  2. Sphingosine Kinase Expression Increases Intracellular Sphingosine-1-Phosphate and Promotes Cell Growth and Survival

    OpenAIRE

    Olivera, Ana; Kohama, Takafumi; Edsall, Lisa; Nava, Victor; Cuvillier, Olivier; Poulton, Samantha; Spiegel, Sarah

    1999-01-01

    Sphingosine-1-phosphate (SPP) is a bioactive lipid that has recently been identified as the ligand for the EDG family of G protein–coupled cell surface receptors. However, the mitogenic and survival effects of exogenous SPP may not correlate with binding to cell-surface receptors (Van Brocklyn, J.R., M.J. Lee, R. Menzeleev, A. Olivera, L. Edsall, O. Cuvillier, D.M. Thomas, P.J.P. Coopman, S. Thangada, T. Hla, and S. Spiegel. 1998. J. Cell Biol. 142:229–240). The recent cloning of sphingosine ...

  3. A H2S-Nampt Dependent Energetic Circuit Is Critical to Survival and Cytoprotection from Damage in Cancer Cells

    OpenAIRE

    Reiko Sanokawa-Akakura; Ostrakhovitch, Elena A.; Shin Akakura; Scott Goodwin; Siamak Tabibzadeh

    2014-01-01

    We recently demonstrated that cancer cells that recover from damage exhibit increased aerobic glycolysis, however, the molecular mechanism by which cancer cells survive the damage and show increased aerobic glycolysis remains unknown. Here, we demonstrate that diverse cancer cells that survive hypoxic or oxidative damage show rapid cell proliferation, and develop tolerance to damage associated with increased production of hydrogen sulfide (H2S) which drives up-regulation of nicotinamide phosp...

  4. 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.

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

    International Nuclear Information System (INIS)

    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

  6. Oestrogen receptor beta over expression in males with non-small cell lung cancer is associated with better survival

    DEFF Research Database (Denmark)

    Skov, Birgit Guldhammer; Sode, Birgitte M Fischer; Pappot, H.

    2008-01-01

    BACKGROUND: Adenocarcinoma of the lung is more frequent in females than in males and the association with smoking is less pronounced than for the other histological subtypes of lung cancer. Oestrogen induction of cell proliferation has been found in breast adenocarcinomas, and since oestrogen...... receptors (ER) have been demonstrated in lung tumours, a similar role of oestrogens in the development of lung cancer has been suggested. We examined the expression of ERalpha, ERbeta and progesterone in a well defined cohort of patients with NSCLC with more than 15 years of follow up, and related the...... immunohistochemical staining and any of the clinical variables, including survival. None of the 104 patients had tumours positive for progesterone. CONCLUSION: The presence of ERbeta in a tumour seems to be a positive prognostic factor for men with non-small cell lung cancer. The finding confirms another recent study...

  7. CD137 is induced by the CD40 signal on chronic lymphocytic leukemia B cells and transduces the survival signal via NF-κB activation.

    Directory of Open Access Journals (Sweden)

    Yukana Nakaima

    Full Text Available CD137 is a member of the tumor necrosis factor receptor family that is expressed on activated T cells. This molecule provides a co-stimulatory signal that enhances the survival, and differentiation of cells, and has a crucial role in the development of CD8 cytotoxic T cells and anti-tumor immunity. Here we report that CD137 expression is also induced on normal or malignant human B cells by CD40 ligation by its ligand CD154. This CD137 induction was more prominent in chronic lymphocytic leukemia (CLL cells than in other types of B cells. CD137 stimulation on B cells by its ligand induced the nuclear translocation of p52 (a non-canonical NF-κB factor. In agreement with this finding, expression of the survival factor BCL-XL was upregulated. Consequently, the CD137 signal augmented the survival of CD154-stimulated CLL B cells in vitro. This unexpected induction of CD137 on B cells by CD40 signal may influence the clinical course of CLL.

  8. Role of anti-stromal polypharmacy in increasing survival after pancreaticoduodenectomy for pancreatic ductal adenocarcinoma

    Institute of Scientific and Technical Information of China (English)

    Samuel; J; Tingle; John; A; Moir; Steven; A; White

    2015-01-01

    AIM: To investigate the survival impact of common pharmaceuticals, which target stromal interactions, following a pancreaticoduodenectomy for pancreatic ductal adenocarcinoma. METHODS: Data was collected retrospectively for 164 patients who underwent a pancreaticoduodenectomy for pancreatic ductal adenocarcinoma(PDAC). Survival analysis was performed on patients receiving the following medications: angiotensin-converting enzyme inhibitors(ACEI)/angiotensin Ⅱ receptor blockers(ARB), calcium channel blockers(CCB), aspirin, and statins. Statistical analysis included Kaplan-meier survival estimates and cox multivariate regression; the latter of which allowed for any differences in a range of prognostic indicators between groups. Medications showing a significant survival benefit were investigated in combination with other medications to evaluate synergistic effects.RESULTS: No survival benefit was observed with respect to ACEI/ARB(n = 41), aspirin or statins on individual drug analysis(n = 39). However, the entire CCB group(n = 26) showed a significant survival benefit on multivariate cox regression; hazard ratio(HR) of 0.475(CI = 0.250-0.902, P = 0.023). Further analysis revealed that this was influenced by a group of patients who were taking aspirin in combination with CCB; median survival was significantly higher in the CCB + aspirin group(n = 15) compared with the group taking neither drug(n = 98); 1414 d vs 601 d(P = 0.029, logrank test). Multivariate cox regression revealed neither aspirin nor CCB had a statistically significant impact on survival when given alone, however in combination the survival benefit was significant; HR = 0.332(CI = 0.126-0.870, P = 0.025). None of the other medications showed a survival benefit in any combination.CONCLUSION: Aspirin + CCB in combination appears to increase survival in patients with PDAC, highlighting the potential clinical use of combination therapy to target stromal interactions in pancreatic cancer.

  9. Macrophage-Associated Osteoactivin/GPNMB Mediates Mesenchymal Stem Cell Survival, Proliferation, and Migration Via a CD44-Dependent Mechanism.

    Science.gov (United States)

    Yu, Bing; Sondag, Gregory R; Malcuit, Christopher; Kim, Min-Ho; Safadi, Fayez F

    2016-07-01

    Although MSCs have been widely recognized to have therapeutic potential in the repair of injured or diseased tissues, it remains unclear how functional activities of mesenchymal stem cells (MSCs) are influenced by the surrounding inflammatory milieu at the site of tissue injury. Macrophages constitute an essential component of innate immunity and have been shown to exhibit a phenotypic plasticity in response to various stimuli, which play a central role in both acute inflammation and wound repair. Osteoactivin (OA)/Glycoprotein non-metastatic melanoma protein B (GPNMB), a transmembrane glycoprotein that plays a role in cell differentiation, survival, and angiogenesis. The objective of this study was to investigate the potential role of OA/GPNMB in macrophage-induced MSC function. We found that reparative M2 macrophages express significantly greater levels of OA/GPNMB than pro-inflammatory M1 macrophages. Furthermore, using loss of function and rescue studies, we demonstrated that M2 macrophages-secreted OA/GPNMB positively regulates the viability, proliferation, and migration of MSCs. More importantly, we demonstrated that OA/GPNMB acts through ERK and AKT signaling pathways in MSCs via CD44, to induce these effects. Taken together, our results provide pivotal insight into the mechanism by which OA/GPNMB contributes to the tissue reparative phenotype of M2 macrophages and positively regulates functional activities of MSCs. J. Cell. Biochem. 117: 1511-1521, 2016. © 2015 Wiley Periodicals, Inc. PMID:26442636

  10. Human T-lymphotropic virus type-1 p30 alters cell cycle G2 regulation of T lymphocytes to enhance cell survival

    Directory of Open Access Journals (Sweden)

    Silverman Lee

    2007-07-01

    Full Text Available Abstract Background Human T-lymphotropic virus type-1 (HTLV-1 causes adult T-cell leukemia/lymphoma and is linked to a number of lymphocyte-mediated disorders. HTLV-1 contains both regulatory and accessory genes in four pX open reading frames. pX ORF-II encodes two proteins, p13 and p30, whose roles are still being defined in the virus life cycle and in HTLV-1 virus-host cell interactions. Proviral clones of HTLV-1 with pX ORF-II mutations diminish the ability of the virus to maintain viral loads in vivo. p30 expressed exogenously differentially modulates CREB and Tax-responsive element-mediated transcription through its interaction with CREB-binding protein/p300 and while acting as a repressor of many genes including Tax, in part by blocking tax/rex RNA nuclear export, selectively enhances key gene pathways involved in T-cell signaling/activation. Results Herein, we analyzed the role of p30 in cell cycle regulation. Jurkat T-cells transduced with a p30 expressing lentivirus vector accumulated in the G2-M phase of cell cycle. We then analyzed key proteins involved in G2-M checkpoint activation. p30 expression in Jurkat T-cells resulted in an increase in phosphorylation at serine 216 of nuclear cell division cycle 25C (Cdc25C, had enhanced checkpoint kinase 1 (Chk1 serine 345 phosphorylation, reduced expression of polo-like kinase 1 (PLK1, diminished phosphorylation of PLK1 at tyrosine 210 and reduced phosphorylation of Cdc25C at serine 198. Finally, primary human lymphocyte derived cell lines immortalized by a HTLV-1 proviral clone defective in p30 expression were more susceptible to camptothecin induced apoptosis. Collectively these data are consistent with a cell survival role of p30 against genotoxic insults to HTLV-1 infected lymphocytes. Conclusion Collectively, our data are the first to indicate that HTLV-1 p30 expression results in activation of the G2-M cell cycle checkpoint, events that would promote early viral spread and T-cell

  11. Estimation of the initial slope of the cell survival curve after irradiation from micronucleus frequency in cytokinesis-blocked cells

    International Nuclear Information System (INIS)

    We have already reported that the α/β ratio of the cell survival curve could be estimated from the micronucleus frequency in cytokinesis-blocked cells treated with cytochalasin-B after irradiation. In this paper, we investigate the direct relationship between the α value and the appearance of micronuclei. Cells of the SCCVII, RIF-1, EMT6, V-79, CHO, HeLa and human esophageal cancer cell lines were used for the study. Low-dose-rate irradiation was used to determine the α component of the relationship between dose and micronucleus frequency according to the linear-quadratic (LQ) model. A reduction of the dose rate from 3.09 to 0.0142 Gy/min correspondingly decreased the micronucleus frequency; however, the fraction of binucleate cells without micronuclei was not affected in SCCVII and RIF-1 cells. When this fraction was defined as the normal nuclear division fraction, it decreased exponentially as a function of radiation dose. Then dose vs normal nuclear division fraction (NNDF) was fitted as follows: -In NNDF = aD + C, where D is radiation dose in grays and C is constant. The slope of the dose vs normal nuclear division fraction was not affected by dose rate. The correlation was also explored between the slope (a) and the α value of the cell survival curve determined by the colony formation assay in cells of eight cell lines. These two values showed extremely high agreement: α = 1.01a + 0.00795 (r = 0.99, P < 0.01). This assay was applied to estimate the α value of the cell survival curve of human esophageal cancer cell lines established from surgical specimens. 13 refs., 5 figs

  12. A nanodosimetry-based linear-quadratic model of cell survival for mixed-LET radiations

    International Nuclear Information System (INIS)

    A new nanodosimetry-based linear-quadratic (LQ) model of cell survival for mixed-LET radiations has been developed. The new model employs three physical quantities and three biological quantities. The three physical quantities are related to energy depositions at two nanometre scales, 5 nm and 25 nm. The three biological quantities are related to the lesion production and interaction probabilities and the lesion repair rate. The coefficients α and β of the LQ formula (αD + βD2) are explicitly expressed in terms of the three physical quantities and the three biological quantities. The new model is shown to be consistent with the previously published cell survival curves of V-79 cells. The advantage of this new model is that it can be conveniently adopted to estimate the iso-effect for radiotherapies that involve ionizing radiation of mixed LET. An example is given to estimate the cell survival fractions for a high-dose-rate mixed neutron and gamma-ray field from a 252Cf source

  13. A nanodosimetry-based linear-quadratic model of cell survival for mixed-LET radiations

    Science.gov (United States)

    Wang, C.-K. Chris; Zhang, Xin

    2006-12-01

    A new nanodosimetry-based linear-quadratic (LQ) model of cell survival for mixed-LET radiations has been developed. The new model employs three physical quantities and three biological quantities. The three physical quantities are related to energy depositions at two nanometre scales, 5 nm and 25 nm. The three biological quantities are related to the lesion production and interaction probabilities and the lesion repair rate. The coefficients α and β of the LQ formula (αD + βD2) are explicitly expressed in terms of the three physical quantities and the three biological quantities. The new model is shown to be consistent with the previously published cell survival curves of V-79 cells. The advantage of this new model is that it can be conveniently adopted to estimate the iso-effect for radiotherapies that involve ionizing radiation of mixed LET. An example is given to estimate the cell survival fractions for a high-dose-rate mixed neutron and gamma-ray field from a 252Cf source.

  14. A nanodosimetry-based linear-quadratic model of cell survival for mixed-LET radiations

    Energy Technology Data Exchange (ETDEWEB)

    Wang, C-K Chris; Zhang, Xin [Nuclear/Radiological Engineering/Medical Physics Program, Neely Research Center, Georgia Institute of Technology, 900 Atlantic Drive, Atlanta, GA 30332-0425 (United States)

    2006-12-07

    A new nanodosimetry-based linear-quadratic (LQ) model of cell survival for mixed-LET radiations has been developed. The new model employs three physical quantities and three biological quantities. The three physical quantities are related to energy depositions at two nanometre scales, 5 nm and 25 nm. The three biological quantities are related to the lesion production and interaction probabilities and the lesion repair rate. The coefficients {alpha} and {beta} of the LQ formula ({alpha}D + {beta}D{sup 2}) are explicitly expressed in terms of the three physical quantities and the three biological quantities. The new model is shown to be consistent with the previously published cell survival curves of V-79 cells. The advantage of this new model is that it can be conveniently adopted to estimate the iso-effect for radiotherapies that involve ionizing radiation of mixed LET. An example is given to estimate the cell survival fractions for a high-dose-rate mixed neutron and gamma-ray field from a {sup 252}Cf source.

  15. 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

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

    International Nuclear Information System (INIS)

    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

  17. 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