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Sample records for cancer senescent fibroblasts

  1. Stromal-epithelial interactions in aging and cancer: Senescent fibroblasts alter epithelial cell differentiation

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    Parrinello, Simona; Coppe, Jean-Philippe; Krtolica, Ana; Campisi, Judith

    2004-07-14

    Cellular senescence suppresses cancer by arresting cells at risk for malignant tumorigenesis. However, senescent cells also secrete molecules that can stimulate premalignant cells to proliferate and form tumors, suggesting the senescence response is antagonistically pleiotropic. We show that premalignant mammary epithelial cells exposed to senescent human fibroblasts in mice irreversibly lose differentiated properties, become invasive and undergo full malignant transformation. Moreover, using cultured mouse or human fibroblasts and non-malignant breast epithelial cells, we show that senescent fibroblasts disrupt epithelial alveolar morphogenesis, functional differentiation, and branching morphogenesis. Further, we identify MMP-3 as the major factor responsible for the effects of senescent fibroblasts on branching morphogenesis. Our findings support the idea that senescent cells contribute to age-related pathology, including cancer, and describe a new property of senescent fibroblasts--the ability to alter epithelial differentiation--that might also explain the loss of tissue function and organization that is a hallmark of aging.

  2. Curcumin Triggers p16-Dependent Senescence in Active Breast Cancer-Associated Fibroblasts and Suppresses Their Paracrine Procarcinogenic Effects

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    Siti-Fauziah Hendrayani

    2013-06-01

    Full Text Available Activated cancer-associated fibroblasts (CAFs or myofibroblasts not only facilitate tumor growth and spread but also affect tumor response to therapeutic agents. Therefore, it became clear that efficient therapeutic regimens should also take into account the presence of these supportive cells and inhibit their paracrine effects. To this end, we tested the effect of low concentrations of curcumin, a pharmacologically safe natural product, on patient-derived primary breast CAF cells. We have shown that curcumin treatment upregulates p16INK4A and other tumor suppressor proteins while inactivates the JAK2/STAT3 pathway. This reduced the level of alpha-smooth muscle actin (α-SMA and the migration/invasion abilities of these cells. Furthermore, curcumin suppressed the expression/secretion of stromal cell-derived factor-1 (SDF-1, interleukin-6 (IL-6, matrix metalloproteinase-2 (MMP-2, MMP-9, and transforming growth factor-β, which impeded their paracrine procarcinogenic potential. Intriguingly, these effects were sustained even after curcumin withdrawal and cell splitting. Therefore, using different markers of senescence [senescence-associated β-galactosidase (SA-β-gal activity, Ki-67 and Lamin B1 levels, and bromodeoxyuridine incorporation], we have shown that curcumin markedly suppresses Lamin B1 and triggers DNA damage-independent senescence in proliferating but not quiescent breast stromal fibroblasts. Importantly, this curcumin-related senescence was p16INK4A-dependent and occurred with no associated inflammatory secretory phenotype. These results indicate the possible inactivation of cancer-associated myofibroblasts and present the first indication that curcumin can trigger DNA damage-independent and safe senescence in stromal fibroblasts.

  3. Secretome Analysis of Human Primary Fibroblasts Undergoing Senescence

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    Rogowska-Wrzesinska, Adelina; Micutkova, Lucia; Diener, Thomas;

    Introduction Cultures of diploid human fibroblasts can replicate only a finite number of times; rapid proliferation is followed by decline in replicative frequency and finally cells become senescent and are incapable of further proliferation. Senescencent cells display altered growth, morphology...... the remaining differentially regulated proteins and to strengthen the results by analysing two additional preparations of primary human fibroblasts.   Innovative aspects Identification of proteins secreted by human primary fibroblasts Identification of difference in secretion patterns between young...... matrix-degrading. In this study we use proteomic tools to characterise the secretome of young and senescent fibroblasts.   Methods Three independent preparations of primary human foreskin fibroblasts were grown to senescence. Young, rapidly proliferating cells at passage 11 and cells from passage 28...

  4. Ciliary abnormalities in senescent human fibroblasts impair proliferative capacity.

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    Breslin, Loretta; Prosser, Suzanna L; Cuffe, Sandra; Morrison, Ciaran G

    2014-01-01

    Somatic cells senesce in culture after a finite number of divisions indefinitely arresting their proliferation. DNA damage and senescence increase the cellular number of centrosomes, the 2 microtubule organizing centers that ensure bipolar mitotic spindles. Centrosomes also provide the basal body from which primary cilia extend to sense and transduce various extracellular signals, notably Hedgehog. Primary cilium formation is facilitated by cellular quiescence a temporary cell cycle exit, but the impact of senescence on cilia is unknown. We found that senescent human fibroblasts have increased frequency and length of primary cilia. Levels of the negative ciliary regulator CP110 were reduced in senescent cells, as were levels of key elements of the Hedgehog pathway. Hedgehog inhibition reduced proliferation in young cells with increased cilium length accompanying cell cycle arrest suggesting a regulatory function for Hedgehog in primary ciliation. Depletion of CP110 in young cell populations increased ciliation frequencies and reduced cell proliferation. These data suggest that primary cilia are potentially novel determinants of the reduced cellular proliferation that initiates senescence. PMID:25486364

  5. Ciliary abnormalities in senescent human fibroblasts impair proliferative capacity

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    Breslin, Loretta; Prosser, Suzanna L; Cuffe, Sandra; Morrison, Ciaran G

    2014-01-01

    Somatic cells senesce in culture after a finite number of divisions indefinitely arresting their proliferation. DNA damage and senescence increase the cellular number of centrosomes, the 2 microtubule organizing centers that ensure bipolar mitotic spindles. Centrosomes also provide the basal body from which primary cilia extend to sense and transduce various extracellular signals, notably Hedgehog. Primary cilium formation is facilitated by cellular quiescence a temporary cell cycle exit, but the impact of senescence on cilia is unknown. We found that senescent human fibroblasts have increased frequency and length of primary cilia. Levels of the negative ciliary regulator CP110 were reduced in senescent cells, as were levels of key elements of the Hedgehog pathway. Hedgehog inhibition reduced proliferation in young cells with increased cilium length accompanying cell cycle arrest suggesting a regulatory function for Hedgehog in primary ciliation. Depletion of CP110 in young cell populations increased ciliation frequencies and reduced cell proliferation. These data suggest that primary cilia are potentially novel determinants of the reduced cellular proliferation that initiates senescence. PMID:25486364

  6. Aging, cellular senescence, and cancer.

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    Campisi, Judith

    2013-01-01

    For most species, aging promotes a host of degenerative pathologies that are characterized by debilitating losses of tissue or cellular function. However, especially among vertebrates, aging also promotes hyperplastic pathologies, the most deadly of which is cancer. In contrast to the loss of function that characterizes degenerating cells and tissues, malignant (cancerous) cells must acquire new (albeit aberrant) functions that allow them to develop into a lethal tumor. This review discusses the idea that, despite seemingly opposite characteristics, the degenerative and hyperplastic pathologies of aging are at least partly linked by a common biological phenomenon: a cellular stress response known as cellular senescence. The senescence response is widely recognized as a potent tumor suppressive mechanism. However, recent evidence strengthens the idea that it also drives both degenerative and hyperplastic pathologies, most likely by promoting chronic inflammation. Thus, the senescence response may be the result of antagonistically pleiotropic gene action. PMID:23140366

  7. Senescence-associated β-galactosidase activity in the in vitro ovarian stromal fibroblasts

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    Lilian Chuaire-Noack

    2011-04-01

    Full Text Available A growing biological research field is the cellular senescence, a mechanism that has been associated, under certain circumstances, withmalignant transformation. Given the high incidence of ovarian cancerand its main origin from the ovarian surface epithelium, as well asthe possibility that an epithelial-mesenchymal transition occurs, weevaluated both the in vitro growth of stromal fibroblasts from the ovarian cortex and their β-galactosidase activity at pH 6,enzyme whose expression is considered as a marker of replicativesenescence. Methods: 48 samples of ovarian cortical fibroblasts fromdonors without a history of cancer were serially cultured untilthe end of their replicative life. β-galactosidase activity at pH 6was quantified in each passage by the chemiluminiscent method. Ascontrol, we used ovarian epithelial cell cultures from the samedonors. The enzyme activity was also evaluated in fibroblastspreviously induced to senescence by exposure to hydrogen peroxide.Results: The analysis of the enzyme activity and the replicativecapacity taken together showed that the fibroblast cultures reachedthe senescent state at passages 4-5, as what happened with the control epithelial cells. Fibroblasts induced to senescence showed high variability in the values of enzymatic activity. Conclusions:The similarity between both types of cells in reaching the senescent state deserves to be taken into account in relation to theepithelialmesenchymal transition that has been proposed to explaintheir behavior in the genesis of cancer arising from ovarian surfaceepithelium. Low β-galactosidase activity values at pH 6 would suggestpossible inactivation of the response pathways to oxidative stress.

  8. A role for SUV39H1-mediated H3K9 trimethylation in the control of genome stability and senescence in WI38 human diploid lung fibroblasts

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    Sidler, Corinne; Woycicki, Rafal; Li, Dongping; Wang, Bo; Kovalchuk, Igor; Kovalchuk, Olga

    2014-01-01

    Cellular senescence has been associated with the age-dependent decline in tissue repair and regeneration, the increasing deterioration of the immune system, and the age-dependent increase in the incidence of cancer. Here, we show that senescence of human lung fibroblast WI-38 cells is associated with extensive changes to the gene expression profile, including the differential expression of transcriptional and epigenetic regulators. Among those, SUV39H1 was downregulated in senescent cells, co...

  9. Senescence and cancer: An evolving inflammatory paradox.

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    Ruhland, Megan K; Coussens, Lisa M; Stewart, Sheila A

    2016-01-01

    The senescent phenotype was first described in 1961 as a phenomenon characterized by the cessation of cellular division. After years of debate as to whether it represented a tissue culture artifact or an important biological process, it is now appreciated that senescence plays an important role in tumorigenesis. Further, senescence is integral to normal biological processes such as embryogenesis and the maintenance of tissue homeostasis. Now with defined roles in development, wound healing, tumor promotion and tumor suppression, it is not surprising that attention has turned to refining our understanding of the mechanisms behind, and consequences of, the induction of senescence. One emerging role for senescence lies in the ability of senescence to orchestrate an inflammatory response: factors secreted by senescent cells have been identified in multiple contexts to modulate various aspects of the immune response. As with many of the previously described roles for senescence, the type of inflammation established by the senescence phenotype is varied and dependent on context. In this review, we discuss the current state of the field with a focus on the paradoxical outcomes of the senescence-induced inflammatory responses in the context of cancer. A more complete understanding of senescence and an appreciation for its complexities will be important for eventual development of senescence-targeted therapies. PMID:26453912

  10. Cisplatin-induced premature senescence with concomitant reduction of gap junctions in human fibroblasts

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    Wei ZHAO; Zhong Xiang LIN; Zhi Qian ZHANG

    2004-01-01

    To examine the role of gap junctions in cell senescence,the changes of gap junctions in cisplatin-induced premature senescence of primary cultured fibroblasts were studied and compared with the replicative senescent human fibroblasts.Dye transfer assay for gap junction function and immunofluorescent staining for connexin 43 protein distribution were done respectively. Furthermore,cytofluorimetry and DAPI fluorescence staining were performed for cell cycle and apoptosis analysis. p53 gene expression level was detected with indirect immunofluorescence. We found that cisplatin (10 mM) treatment could block cell growth cycle at G1 and induced premature senescence. The premature senescence changes included high frequency of apoptosis,elevation of p53 expression,loss of membranous gap junctions and reduction of dye-transfer capacity. These changes were comparable to the changes of replicative senescence of human fibroblasts. It was also concluded that cisplatin could induce premature senescence concomitant with inhibition of gap junctions in the fibroblasts. Loss of functional gap junctions from the cell membrane may account for the reduced intercellular communication in the premature senescent fibroblasts. The cell system we used may provide a model useful for the study of the gap junction thus promoting agents against premature senescence.

  11. Aminoguanidine delays the replicative senescence of human diploid fibroblasts

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    WANG Pei-chang; ZHANG Jian; ZHANG Zong-yu; TONG Tan-jun

    2007-01-01

    advanced glycation end products; comet assayBackground The accumulation of free radicals and advanced glycation end products (AGEs) in cell plays a very important role in replicative senescence. Aminoguanidine (AG) has potential antioxidant effects and decreases AGE levels. This study aimed to investigate its effect on replicative senescence in vitro.Methods The effects of aminoguanidine on morphology, replicative lifespan, cell growth and proliferation, AGEs, DNA damage, DNA repair ability and telomere length were observed in human fetal lung diploid fibroblasts (2BS).Results Aminoguanidine maintained the non-senescent phenotype of 2BS cells even at late population doubling (PD) and increased cumulative population doublings by at least 17-21 PDs. Aminoguanidine also improved the potentials of growth and proliferation of 2BS cells as detected by the MTT assay. The AGE levels of late PD cells grown from early PD in DMEM containing aminiguanidine decreased significantly compared with those of late PD control cells and were similar to those of young control cells. In addition, the cells pretreated with aminoguanidine had a significant reduction in DNA strand breaks when they were exposed to 200 μmol/L H2O2 for 5 minutes which indicated that the compound had a strong potential to protect genomic DNA against oxidative stress. And most of the cells exposed to 100 μmol/L H2O2 had much shorter comet tails and smaller tail areas after incubation with aminoguanidine-supplemented DMEM, which indicated that the compound strongly improved the DNA repair abilities of 2BS cells. Moreover, PD55 cells grown from PD28 in 2 mmol/L or 4 mmol/L aminoguanidine retain telomere lengths of 7.94 kb or 8.12 kb, which was 0.83 kb or 1.11kb longer than that of the control cells.Conclusion Aminoguanidine delays replicative senescence of 2BS cells and the senescence-delaying effect of aminoguanidine appear to be due to its many biological properties including its potential for proliferation

  12. Senescence induction; a possible cancer therapy

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    Kondoh Hiroshi; Artero-Castro Ana; LLeonart Matilde E

    2009-01-01

    Abstract Cellular immortalization is a crucial step during the development of human cancer. Primary mammalian cells reach replicative exhaustion after several passages in vitro, a process called replicative senescence. During such a state of permanent growth arrest, senescent cells are refractory to physiological proliferation stimuli: they have altered cell morphology and gene expression patterns, although they remain viable with preserved metabolic activity. Interestingly, senescent cells h...

  13. Senescence induction; a possible cancer therapy

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    Kondoh Hiroshi

    2009-01-01

    Full Text Available Abstract Cellular immortalization is a crucial step during the development of human cancer. Primary mammalian cells reach replicative exhaustion after several passages in vitro, a process called replicative senescence. During such a state of permanent growth arrest, senescent cells are refractory to physiological proliferation stimuli: they have altered cell morphology and gene expression patterns, although they remain viable with preserved metabolic activity. Interestingly, senescent cells have also been detected in vivo in human tumors, particularly in benign lesions. Senescence is a mechanism that limits cellular lifespan and constitutes a barrier against cellular immortalization. During immortalization, cells acquire genetic alterations that override senescence. Tumor suppressor genes and oncogenes are closely involved in senescence, as their knockdown and ectopic expression confer immortality and senescence induction, respectively. By using high throughput genetic screening to search for genes involved in senescence, several candidate oncogenes and putative tumor suppressor genes have been recently isolated, including subtypes of micro-RNAs. These findings offer new perspectives in the modulation of senescence and open new approaches for cancer therapy.

  14. Knockdown of CDK2AP1 in primary human fibroblasts induces p53 dependent senescence.

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    Khaled N Alsayegh

    Full Text Available Cyclin Dependent Kinase-2 Associated Protein-1 (CDK2AP1 is known to be a tumor suppressor that plays a role in cell cycle regulation by sequestering monomeric CDK2, and targeting it for proteolysis. A reduction of CDK2AP1 expression is considered to be a negative prognostic indicator in patients with oral squamous cell carcinoma and also associated with increased invasion in human gastric cancer tissue. CDK2AP1 overexpression was shown to inhibit growth, reduce invasion and increase apoptosis in prostate cancer cell lines. In this study, we investigated the effect of CDK2AP1 downregulation in primary human dermal fibroblasts. Using a short-hairpin RNA to reduce its expression, we found that knockdown of CDK2AP1 in primary human fibroblasts resulted in reduced proliferation and in the induction of senescence associated beta-galactosidase activity. CDK2AP1 knockdown also resulted in a significant reduction in the percentage of cells in the S phase and an accumulation of cells in the G1 phase of the cell cycle. Immunocytochemical analysis also revealed that the CDK2AP1 knockdown significantly increased the percentage of cells that exhibited γ-H2AX foci, which could indicate presence of DNA damage. CDK2AP1 knockdown also resulted in increased mRNA levels of p53, p21, BAX and PUMA and p53 protein levels. In primary human fibroblasts in which p53 and CDK2AP1 were simultaneously downregulated, there was: (a no increase in senescence associated beta-galactosidase activity, (b decrease in the number of cells in the G1-phase and increase in number of cells in the S-phase of the cell cycle, and (c decrease in the mRNA levels of p21, BAX and PUMA when compared with CDK2AP1 knockdown only fibroblasts. Taken together, this suggests that the observed phenotype is p53 dependent. We also observed a prominent increase in the levels of ARF protein in the CDK2AP1 knockdown cells, which suggests a possible role of ARF in p53 stabilization following CDK2AP1

  15. Insulin-like growth factor binding protein-6 delays replicative senescence of human fibroblasts

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    Micutkova, Lucia; Diener, Thomas; Li, Chen;

    2011-01-01

    Cellular senescence can be induced by a variety of mechanisms, and recent data suggest a key role for cytokine networks to maintain the senescent state. Here, we have used a proteomic LC-MS/MS approach to identify new extracellular regulators of senescence in human fibroblasts. We identified 26...... extracellular proteins with significantly different abundance in conditioned media from young and senescent fibroblasts. Among these was insulin-like growth factor binding protein-6 (IGFBP-6), which was chosen for further analysis. When IGFBP-6 gene expression was downregulated, cell proliferation was inhibited...... and apoptotic cell death was increased. Furthermore, downregulation of IGFBP-6 led to premature entry into cellular senescence. Since IGFBP-6 overexpression increased cellular lifespan, the data suggest that IGFBP-6, in contrast to other IGF binding proteins, is a negative regulator of cellular...

  16. The microRNA miR-17-3p inhibits mouse cardiac fibroblast senescence by targeting Par4.

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    Du, William W; Li, Xianmin; Li, Tianbi; Li, Haoran; Khorshidi, Azam; Liu, Fengqiong; Yang, Burton B

    2015-01-15

    The microRNA miR-17-92 cluster plays a fundamental role in heart development. The aim of this study was to investigate the effect of a member of this cluster, miR-17, on cardiac senescence. We examined the roles of miR-17 in senescence and demonstrated that miR-17-3p attenuates cardiac aging in the myocardium by targeting Par4 (also known as PAWR). This upregulates the downstream proteins CEBPB, FAK, N-cadherin, vimentin, Oct4 and Sca-1 (also known as stem cell antigen-1), and downregulates E-cadherin. Par4 has been reported as a tumor suppressor gene that induces apoptosis in cancer cells, but not in normal cells. Repression of Par4 by miR-17-3p enhances the transcription of CEBPB and FAK, which promotes mouse cardiac fibroblast (MCF) epithelial-to-mesenchymal transition (EMT) and self-renewal, resulting in cellular senescence and apoptosis resistance. We conclude that Par4 can bind to the CEBPB promoter and inhibit its transcription. Decreased Par4 expression increases the amount of CEBPB, which binds to the FAK promoter and enhances FAK transcription. Par4, CEBPB and FAK form a senescence signaling pathway, playing roles in modulating cell survival, growth, apoptosis, EMT and self-renewal. Through this novel senescence signaling axis, miR-17-3p represses Par4 expression, acting pleiotropically as a negative modulator of cardiac aging and cardiac fibroblast cellular senescence. PMID:25472717

  17. Conserved Senescence Associated Genes and Pathways in Primary Human Fibroblasts Detected by RNA-Seq.

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    S Marthandan

    Full Text Available Cellular senescence correlates with changes in the transcriptome. To obtain a complete view on senescence-associated transcription networks and pathways, we assessed by deep RNA sequencing the transcriptomes of five of the most commonly used laboratory strains of human fibroblasts during their transition into senescence. In a number of cases, we verified the RNA-seq data by real-time PCR. By determining cellular protein levels we observed that the age-related expression of most but not all genes is regulated at the transcriptional level. We found that 78% of the age-affected differentially expressed genes were commonly regulated in the same direction (either up- or down-regulated in all five fibroblast strains, indicating a strong conservation of age-associated changes in the transcriptome. KEGG pathway analyses confirmed up-regulation of the senescence-associated secretory phenotype and down-regulation of DNA synthesis/repair and most cell cycle pathways common in all five cell strains. Newly identified senescence-induced pathways include up-regulation of endocytotic/phagocytic pathways and down-regulation of the mRNA metabolism and the mRNA splicing pathways. Our results provide an unprecedented comprehensive and deep view into the individual and common transcriptome and pathway changes during the transition into of senescence of five human fibroblast cell strains.

  18. MiRNA profile associated with replicative senescence, extended cell culture, and ectopic telomerase expression in human foreskin fibroblasts.

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    Laura N Bonifacio

    Full Text Available Senescence is a highly regulated process that limits cellular replication by enforcing a G1 arrest in response to various stimuli. Replicative senescence occurs in response to telomeric DNA erosion, and telomerase expression can offset replicative senescence leading to immortalization of many human cells. Limited data exists regarding changes of microRNA (miRNA expression during senescence in human cells and no reports correlate telomerase expression with regulation of senescence-related miRNAs. We used miRNA microarrays to provide a detailed account of miRNA profiles for early passage and senescent human foreskin (BJ fibroblasts as well as early and late passage immortalized fibroblasts (BJ-hTERT that stably express the human telomerase reverse transcriptase subunit hTERT. Selected miRNAs that were differentially expressed in senescence were assayed for expression in quiescent cells to identify miRNAs that are specifically associated with senescence-associated growth arrest. From this group of senescence-associated miRNAs, we confirmed the ability of miR-143 to induce growth arrest after ectopic expression in young fibroblasts. Remarkably, miR-143 failed to induce growth arrest in BJ-hTERT cells. Importantly, the comparison of late passage immortalized fibroblasts to senescent wild type fibroblasts reveals that miR-146a, a miRNA with a validated role in regulating the senescence associated secretory pathway, is also regulated during extended cell culture independently of senescence. The discovery that miRNA expression is impacted by expression of ectopic hTERT as well as extended passaging in immortalized fibroblasts contributes to a comprehensive understanding of the connections between telomerase expression, senescence and processes of cellular aging.

  19. Persistent Amplification of DNA Damage Signal Involved in Replicative Senescence of Normal Human Diploid Fibroblasts

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    Masatoshi Suzuki

    2012-01-01

    Full Text Available Foci of phosphorylated histone H2AX and ATM are the surrogate markers of DNA double strand breaks. We previously reported that the residual foci increased their size after irradiation, which amplifies DNA damage signals. Here, we addressed whether amplification of DNA damage signal is involved in replicative senescence of normal human diploid fibroblasts. Large phosphorylated H2AX foci (>1.5 μm diameter were specifically detected in presenescent cells. The frequency of cells with large foci was well correlated with that of cells positive for senescence-associated β-galactosidase staining. Hypoxic cell culture condition extended replicative life span of normal human fibroblast, and we found that the formation of large foci delayed in those cells. Our immuno-FISH analysis revealed that large foci partially localized at telomeres in senescent cells. Importantly, large foci of phosphorylated H2AX were always colocalized with phosphorylated ATM foci. Furthermore, Ser15-phosphorylated p53 showed colocalization with the large foci. Since the treatment of senescent cells with phosphoinositide 3-kinase inhibitor, wortmannin, suppressed p53 phosphorylation, it is suggested that amplification of DNA damage signaling sustains persistent activation of ATM-p53 pathway, which is essential for replicative senescence.

  20. Lung fibroblasts from patients with emphysema show markers of senescence in vitro

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    Nakashima M

    2006-02-01

    Full Text Available Abstract Background The loss of alveolar walls is a hallmark of emphysema. As fibroblasts play an important role in the maintenance of alveolar structure, a change in fibroblast phenotype could be involved in the pathogenesis of this disease. In a previous study we found a reduced in vitro proliferation rate and number of population doublings of parenchymal lung fibroblasts from patients with emphysema and we hypothesized that these findings could be related to a premature cellular aging of these cells. In this study, we therefore compared cellular senescence markers and expression of respective genes between lung fibroblasts from patients with emphysema and control patients without COPD. Methods Primary lung fibroblasts were obtained from 13 patients with moderate to severe lung emphysema (E and 15 controls (C undergoing surgery for lung tumor resection or volume reduction (n = 2. Fibroblasts (8E/9C were stained for senescence-associated β-galactosidase (SA-β-Gal. In independent cultures, DNA from lung fibroblasts (7E/8C was assessed for mean telomere length. Two exploratory 12 k cDNA microarrays were used to assess gene expression in pooled fibroblasts (3E/3C. Subsequently, expression of selected genes was evaluated by quantitative PCR (qPCR in fibroblasts of individual patients (10E/9C and protein concentration was analyzed in the cell culture supernatant. Results The median (quartiles percentage of fibroblasts positive for SA-β-Gal was 4.4 (3.2;4.7 % in controls and 16.0 (10.0;24.8 % in emphysema (p = 0.001, while telomere length was not different. Among the candidates for differentially expressed genes in the array (factor ≥ 3, 15 were upregulated and 121 downregulated in emphysema. qPCR confirmed the upregulation of insulin-like growth factor-binding protein (IGFBP-3 and IGFBP-rP1 (p = 0.029, p = 0.0002, while expression of IGFBP-5, -rP2 (CTGF, -rP4 (Cyr61, FOSL1, LOXL2, OAZ1 and CDK4 was not different between groups. In line with the

  1. The Identification of Senescence-Specific Genes during the Induction of Senescence in Prostate Cancer Cells

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    Steven R. Schwarze

    2005-09-01

    Full Text Available Classic mechanisms of tumor response to chemotherapy include apoptosis, mitotic catastrophe. Recent studies have suggested that cellular senescence, a terminal proliferation arrest seen in vitro, may be invoked during the exposure of cancer cells to chemotherapeutic agents. To identify markers associated specifically with the cellular senescence phenotype, we utilized expression data from cDNA microarray experiments identifying transcripts whose expression levels increased as human prostate epithelial cells progressed to senescence. When screened against other growth-inhibitory conditions, including quiescence, apoptosis, many of these transcripts were also upregulated, indicating that similar pathways occur between apoptosis, senescence. A senescent-like phenotype was then induced in several prostate cancer cell lines using 5-aza-2′-deoxycytidine, doxorubicin, or Docetaxel. Treatment with these agents resulted in a significant increase in the induction of senescence-specific genes when compared to nonsenescent conditions. The performance of the panel was improved with fluorescence-activated cell sorting using PKH26 to isolate nonproliferating, viable, drug-treated populations, indicating that a heterogeneous response occurs with chemotherapy. We have defined an RNA-based gene panel that characterizes the senescent phenotype induced in cancer cells by drug treatment. These data also indicate that a panel of genes, rather than one marker, needs to be utilized to identify senescence.

  2. Modulation of Cell Cycle Profile by Chlorella vulgaris Prevents Replicative Senescence of Human Diploid Fibroblasts

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    Tayyebeh Saberbaghi

    2013-01-01

    Full Text Available In this study, the effects of Chlorella vulgaris (CV on replicative senescence of human diploid fibroblasts (HDFs were investigated. Hot water extract of CV was used to treat HDFs at passages 6, 15, and 30 which represent young, presenescence, and senescence ages, respectively. The level of DNA damage was determined by comet assay while apoptosis and cell cycle profile were determined using FACSCalibur flow cytometer. Our results showed direct correlation between increased levels of damaged DNA and apoptosis with senescence in untreated HDFs (P<0.05. Cell cycle profile showed increased population of untreated senescent cells that enter G0/G1 phase while the cell population in S phase decreased significantly (P<0.05. Treatment with CV however caused a significant reduction in the level of damaged DNA and apoptosis in all age groups of HDFs (P<0.05. Cell cycle analysis showed that treatment with CV increased significantly the percentage of senescent HDFs in S phase and G2/M phases but decreased the population of cells in G0/G1 phase (P<0.05. In conclusion, hot water extract of Chlorella vulgaris effectively decreased the biomarkers of ageing, indicating its potential as an antiageing compound.

  3. Gamma-Tocotrienol Modulated Gene Expression in Senescent Human Diploid Fibroblasts as Revealed by Microarray Analysis

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    Suzana Makpol

    2013-01-01

    Full Text Available The effect of γ-tocotrienol, a vitamin E isomer, in modulating gene expression in cellular aging of human diploid fibroblasts was studied. Senescent cells at passage 30 were incubated with 70 μM of γ-tocotrienol for 24 h. Gene expression patterns were evaluated using Sentrix HumanRef-8 Expression BeadChip from Illumina, analysed using GeneSpring GX10 software, and validated using quantitative RT-PCR. A total of 100 genes were differentially expressed (P<0.001 by at least 1.5 fold in response to γ-tocotrienol treatment. Amongst the genes were IRAK3, SelS, HSPA5, HERPUD1, DNAJB9, SEPR1, C18orf55, ARF4, RINT1, NXT1, CADPS2, COG6, and GLRX5. Significant gene list was further analysed by Gene Set Enrichment Analysis (GSEA, and the Normalized Enrichment Score (NES showed that biological processes such as inflammation, protein transport, apoptosis, and cell redox homeostasis were modulated in senescent fibroblasts treated with γ-tocotrienol. These findings revealed that γ-tocotrienol may prevent cellular aging of human diploid fibroblasts by modulating gene expression.

  4. Protein modification and replicative senescence of WI-38 human embryonic fibroblasts

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    Ahmed, Emad K; Rogowska-Wrzesinska, Adelina; Roepstorff, Peter;

    2010-01-01

    Summary Oxidized proteins as well as proteins modified by the lipid peroxidation product 4-hydroxy-2-nonenal (HNE) and by glycation (AGE) have been shown to accumulate with aging in vivo and during replicative senescence in vitro. To better understand the mechanisms by which these damaged proteins...... build up and potentially affect cellular function during replicative senescence of WI-38 fibroblasts, proteins targeted by these modifications have been identified using a bidimensional gel electrophoresis-based proteomic approach coupled with immunodetection of HNE-, AGE-modified and carbonylated...... proteins. 37 proteins targeted for either one of these modifications were identified by mass spectrometry and are involved in different cellular functions such as protein quality control, energy metabolism and cytoskeleton. Almost half of the identified proteins were found to be mitochondrial, which...

  5. The role of senescence and prosurvival signaling in controlling the oncogenic activity of FGFR2 mutants associated with cancer and birth defects

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    Ota, Sara; Zhou, Zi-Qiang; Link, Jason M; Hurlin, Peter J.

    2009-01-01

    Mutations in fibroblast growth factor receptors (FGFRs) cause human birth defect syndromes and are associated with a variety of cancers. Although forced expression of mutant activated FGFRs has been shown to oncogenically transform some immortal cell types, their activity in primary cells remains unclear. Here, we show that birth defect and cancer-associated FGFR2 mutants promote DNA-damage signaling and p53-dependent senescence in primary mouse and human cells. Senescence promoted by FGFR mu...

  6. Senescent cells harbour features of the cancer epigenome

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    Cruickshanks, Hazel A; McBryan, Tony; Nelson, David M.; VanderKraats, Nathan D.; Shah, Parisha P.; van Tuyn, John; Rai, Taranjit Singh; Brock, Claire; Donahue, Greg; Dunican, Donncha S; Drotar, Mark E.; Meehan, Richard R.; Edwards, John R.; Berger, Shelley L.; Adams, Peter D.

    2013-01-01

    Altered DNA methylation and associated destabilization of genome integrity and function is a hallmark of cancer. Replicative senescence is a tumour suppressor process that imposes a limit on the proliferative potential of normal cells that all cancer cells must bypass. Here we show by whole-genome single-nucleotide bisulfite sequencing that replicative senescent human cells exhibit widespread DNA hypomethylation and focal hypermethylation. Hypomethylation occurs preferentially at gene-poor, l...

  7. Cellular and molecular biomarkers indicate precocious in vitro senescence in fibroblasts from SAMP6 mice. Evidence supporting a murine model of premature senescence and osteopenia.

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    Lecka-Czernik, B; Moerman, E J; Shmookler Reis, R J; Lipschitz, D A

    1997-11-01

    A variety of short-lived mouse strains (SAMP strains) and control strains of less abbreviated life span (SAMR strains) have been proposed as murine models of accelerated senescence. Each SAMP strain, in addition to displaying "progeroid" traits of accelerated aging, exhibits a singular age-related pathology. The application of this animal model to the study of normal aging processes has been and remains controversial. Therefore, we have undertaken a study of dermal fibroblasts derived from the short-lived SAMP6 strain, which shows early-onset and progressive osteopenia. We have investigated cellular and molecular characteristics that are associated with in vitro aging of normal human fibroblasts, and which are exacerbated in fibroblasts from patients with Werner syndrome, a human model of premature senescence. We found that SAMP6 dermal fibroblasts, relative to SAMR1 and C57BL/6 controls, exhibit characteristics of premature or accelerated cellular senescence with regard to in vitro life span, initial growth rate, and patterns of gene expression. PMID:9402934

  8. T-helper-1-cell cytokines drive cancer into senescence.

    Science.gov (United States)

    Braumüller, Heidi; Wieder, Thomas; Brenner, Ellen; Aßmann, Sonja; Hahn, Matthias; Alkhaled, Mohammed; Schilbach, Karin; Essmann, Frank; Kneilling, Manfred; Griessinger, Christoph; Ranta, Felicia; Ullrich, Susanne; Mocikat, Ralph; Braungart, Kilian; Mehra, Tarun; Fehrenbacher, Birgit; Berdel, Julia; Niessner, Heike; Meier, Friedegund; van den Broek, Maries; Häring, Hans-Ulrich; Handgretinger, Rupert; Quintanilla-Martinez, Leticia; Fend, Falko; Pesic, Marina; Bauer, Jürgen; Zender, Lars; Schaller, Martin; Schulze-Osthoff, Klaus; Röcken, Martin

    2013-02-21

    Cancer control by adaptive immunity involves a number of defined death and clearance mechanisms. However, efficient inhibition of exponential cancer growth by T cells and interferon-γ (IFN-γ) requires additional undefined mechanisms that arrest cancer cell proliferation. Here we show that the combined action of the T-helper-1-cell cytokines IFN-γ and tumour necrosis factor (TNF) directly induces permanent growth arrest in cancers. To safely separate senescence induced by tumour immunity from oncogene-induced senescence, we used a mouse model in which the Simian virus 40 large T antigen (Tag) expressed under the control of the rat insulin promoter creates tumours by attenuating p53- and Rb-mediated cell cycle control. When combined, IFN-γ and TNF drive Tag-expressing cancers into senescence by inducing permanent growth arrest in G1/G0, activation of p16INK4a (also known as CDKN2A), and downstream Rb hypophosphorylation at serine 795. This cytokine-induced senescence strictly requires STAT1 and TNFR1 (also known as TNFRSF1A) signalling in addition to p16INK4a. In vivo, Tag-specific T-helper 1 cells permanently arrest Tag-expressing cancers by inducing IFN-γ- and TNFR1-dependent senescence. Conversely, Tnfr1(-/-)Tag-expressing cancers resist cytokine-induced senescence and grow aggressively, even in TNFR1-expressing hosts. Finally, as IFN-γ and TNF induce senescence in numerous murine and human cancers, this may be a general mechanism for arresting cancer progression. PMID:23376950

  9. Bisdemethoxycurcumin Increases Sirt1 to Antagonize t-BHP-Induced Premature Senescence in WI38 Fibroblast Cells

    Directory of Open Access Journals (Sweden)

    Ying-Bo Li

    2013-01-01

    Full Text Available Curcuminoids are well known for their capabilities to combat risk factors that are associated with ageing and cellular senescence. Recent reports have demonstrated that curcuminoids can extend the lifespan of model organisms. However, the underlying mechanisms by which these polyphenic compounds exert these beneficial effects remain unknown. In this study, t-BHP-induced premature senescence model in human fibroblasts was chosen to explore the protective effects of a curcuminoid, bisdemethoxycurcumin (BDMC, on cellular senescence. The results demonstrated that BDMC attenuated oxidative stress-induced senescence-like features which include the induction of an enlarged cellular appearance, higher frequency of senescence-associated β-galactosidase staining activity, appearance of senescence-associated heterochromatic foci in nuclei, decrease in proliferation capability, and alteration in related molecules such as p16 and retinoblastoma protein. Notably, we found that BDMC treatment activated Sirt1/AMPK signaling pathway. Moreover, downregulating Sirt1 by the pharmacological inhibitor nicotianamine or small interfering RNA blocked BDMC-mediated protection against t-BHP-mediated decrease in proliferation. These results suggested that BDMC prevented t-BHP-induced cellular senescence, and BDMC-induced Sirt1 may be a mechanism mediating its beneficial effects.

  10. Cordyceps militaris Extract Protects Human Dermal Fibroblasts against Oxidative Stress-Induced Apoptosis and Premature Senescence

    Directory of Open Access Journals (Sweden)

    Jun Myoung Park

    2014-09-01

    Full Text Available Oxidative stress induced by reactive oxygen species (ROS is the major cause of degenerative disorders including aging and disease. In this study, we investigated whether Cordyceps militaris extract (CME has in vitro protective effects on hydrogen peroxide-induced oxidative stress in human dermal fibroblasts (HDFs. Our results showed that the 2,2-diphenyl-1-picrylhydrazyl (DPPH radical scavenging activity of CME was increased in a dose-dependent manner. We found that hydrogen peroxide treatment in HDFs increased ROS generation and cell death as compared with the control. However, CME improved the survival of HDFs against hydrogen peroxide-induced oxidative stress via inhibition of intracellular ROS production. CME treatment inhibited hydrogen peroxide-induced apoptotic cell death and apoptotic nuclear condensation in HDFs. In addition, CME prevented hydrogen peroxide-induced SA-β-gal-positive cells suggesting CME could inhibit oxidative stress-induced premature senescence. Therefore, these results suggest that CME might have protective effects against oxidative stress-induced premature senescence via scavenging ROS.

  11. T-helper-1-cell cytokines drive cancer into senescence

    OpenAIRE

    Braumüller, Heidi; Wieder, Thomas; Brenner, Ellen; Aßmann, Sonja; Hahn, Matthias; Alkhaled, Mohammed; Schilbach, Karin; Essmann, Frank; Kneilling, Manfred; Griessinger, Christoph; Ranta, Felicia; Ullrich, Susanne; Mocikat, Ralph; Braungart, Kilian; Mehra, Tarun

    2013-01-01

    Cancer control by adaptive immunity involves a number of defined death and clearance mechanisms. However, efficient inhibition of exponential cancer growth by T cells and interferon-γ (IFN-γ) requires additional undefined mechanisms that arrest cancer cell proliferation. Here we show that the combined action of the T-helper-1-cell cytokines IFN-γ and tumour necrosis factor (TNF) directly induces permanent growth arrest in cancers. To safely separate senescence induced by tumour immunity from ...

  12. The impact of cellular senescence in cancer therapy:is it true or not?

    Institute of Scientific and Technical Information of China (English)

    Yi ZHANG; Jin-ming YANG

    2011-01-01

    Cellular senescence is defined as the physiological program of terminal growth arrest,which can be triggered by various endogenous or exogenous stress signals.Cellular senescence can be induced in response to oncogenic activation and acts as a barrier to tumorigenesis.Moreover,tumor cells can undergo senescence when exposed to chemotherapeutic agents.In addition to suppressing tumorigenesis,senescent cells remain metabolically active and may contribute to tumor formation and to therapy resistance.In the current review,we discuss the molecular regulation of cellular senescence,the potential implications of senescence in human cancers,and the possibility of exploiting cellular senescence for the treatment of cancers.

  13. Role of senescence and mitotic catastrophe in cancer therapy

    Directory of Open Access Journals (Sweden)

    Shukla Yogeshwer

    2010-01-01

    Full Text Available Abstract Senescence and mitotic catastrophe (MC are two distinct crucial non-apoptotic mechanisms, often triggered in cancer cells and tissues in response to anti-cancer drugs. Chemotherapeuticals and myriad other factors induce cell eradication via these routes. While senescence drives the cells to a state of quiescence, MC drives the cells towards death during the course of mitosis. The senescent phenotype distinguishes tumor cells that survived drug exposure but lost the ability to form colonies from those that recover and proliferate after treatment. Although senescent cells do not proliferate, they are metabolically active and may secrete proteins with potential tumor-promoting activities. The other anti-proliferative response of tumor cells is MC that is a form of cell death that results from abnormal mitosis and leads to the formation of interphase cells with multiple micronuclei. Different classes of cytotoxic agents induce MC, but the pathways of abnormal mitosis differ depending on the nature of the inducer and the status of cell-cycle checkpoints. In this review, we compare the two pathways and mention that they are activated to curb the growth of tumors. Altogether, we have highlighted the possibilities of the use of senescence targeting drugs, mitotic kinases and anti-mitotic agents in fabricating novel strategies in cancer control.

  14. Histone deacetylase inhibitor valproic acid promotes the induction of pluripotency in mouse fibroblasts by suppressing reprogramming-induced senescence stress

    International Nuclear Information System (INIS)

    Histone deacetylase inhibitor valproic acid (VPA) has been used to increase the reprogramming efficiency of induced pluripotent stem cell (iPSC) from somatic cells, yet the specific molecular mechanisms underlying this effect is unknown. Here, we demonstrate that reprogramming with lentiviruses carrying the iPSC-inducing factors (Oct4-Sox2-Klf4-cMyc, OSKM) caused senescence in mouse fibroblasts, establishing a stress barrier for cell reprogramming. Administration of VPA protected cells from reprogramming-induced senescent stress. Using an in vitro pre-mature senescence model, we found that VPA treatment increased cell proliferation and inhibited apoptosis through the suppression of the p16/p21 pathway. In addition, VPA also inhibited the G2/M phase blockage derived from the senescence stress. These findings highlight the role of VPA in breaking the cell senescence barrier required for the induction of pluripotency. - Highlights: • Histone deacetylase inhibitor valproic acid enhances iPSC induction. • Valproic acid suppresses reprogramming-induced senescence stress. • Valproic acid downregulates the p16/p21 pathway in reprogramming. • This study demonstrates a new mechanistic role of valproic acid in enhancing reprogramming

  15. UV light induces premature senescence in Akt1-null mouse embryonic fibroblasts by increasing intracellular levels of ROS

    International Nuclear Information System (INIS)

    Akt/PKB plays a pivotal role in cell survival and proliferation. Previously, we reported that UV-irradiation induces extensive cell death in Akt2-/- mouse embryonic fibroblasts (MEFs) while Akt1-/- MEFs show cell cycle arrest. Here, we find that Akt1-/- MEFs exhibit phenotypic changes characteristics of senescence upon UV-irradiation. An enlarged and flattened morphology, a reduced cell proliferation and an increased senescence-associated β-galactosidase (SA β-gal) staining indicate that Akt1-/- MEFs undergo premature senescence after UV-irradiation. Restoring Akt1 expression in Akt1-/- MEFs suppressed SA β-gal activity, indicating that UV-induced senescence is due to the absence of Akt1 function. Notably, levels of ROS were rapidly increased upon UV-irradiation and the ROS scavenger NAC inhibits UV-induced senescence of Akt1-/- MEFs, suggesting that UV light induces premature senescence in Akt1-/- MEFs by modulating intracellular levels of ROS. In conjunction with our previous work, this indicates that different isoforms of Akt have distinct function in response to UV-irradiation.

  16. Histone deacetylase inhibitor valproic acid promotes the induction of pluripotency in mouse fibroblasts by suppressing reprogramming-induced senescence stress

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Yingying; Chen, Xi; Yu, Dehai [Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061 (China); Stanford University Medical School, Palo Alto Veterans Institute for Research, Palo Alto, CA 94304 (United States); Li, Tao [Stanford University Medical School, Palo Alto Veterans Institute for Research, Palo Alto, CA 94304 (United States); Cui, Jiuwei; Wang, Guanjun [Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061 (China); Hu, Ji-Fan, E-mail: jifan@stanford.edu [Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061 (China); Stanford University Medical School, Palo Alto Veterans Institute for Research, Palo Alto, CA 94304 (United States); Li, Wei, E-mail: jdyylw@163.com [Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061 (China)

    2015-09-10

    Histone deacetylase inhibitor valproic acid (VPA) has been used to increase the reprogramming efficiency of induced pluripotent stem cell (iPSC) from somatic cells, yet the specific molecular mechanisms underlying this effect is unknown. Here, we demonstrate that reprogramming with lentiviruses carrying the iPSC-inducing factors (Oct4-Sox2-Klf4-cMyc, OSKM) caused senescence in mouse fibroblasts, establishing a stress barrier for cell reprogramming. Administration of VPA protected cells from reprogramming-induced senescent stress. Using an in vitro pre-mature senescence model, we found that VPA treatment increased cell proliferation and inhibited apoptosis through the suppression of the p16/p21 pathway. In addition, VPA also inhibited the G2/M phase blockage derived from the senescence stress. These findings highlight the role of VPA in breaking the cell senescence barrier required for the induction of pluripotency. - Highlights: • Histone deacetylase inhibitor valproic acid enhances iPSC induction. • Valproic acid suppresses reprogramming-induced senescence stress. • Valproic acid downregulates the p16/p21 pathway in reprogramming. • This study demonstrates a new mechanistic role of valproic acid in enhancing reprogramming.

  17. Stem cells, senescence, neosis and self-renewal in cancer

    Directory of Open Access Journals (Sweden)

    Rajaraman Murali M

    2006-11-01

    Full Text Available Abstract We describe the basic tenets of the current concepts of cancer biology, and review the recent advances on the suppressor role of senescence in tumor growth and the breakdown of this barrier during the origin of tumor growth. Senescence phenotype can be induced by (1 telomere attrition-induced senescence at the end of the cellular mitotic life span (MLS* and (2 also by replication history-independent, accelerated senescence due to inadvertent activation of oncogenes or by exposure of cells to genotoxins. Tumor suppressor genes p53/pRB/p16INK4A and related senescence checkpoints are involved in effecting the onset of senescence. However, senescence as a tumor suppressor mechanism is a leaky process and senescent cells with mutations or epimutations in these genes escape mitotic catastrophe-induced cell death by becoming polyploid cells. These polyploid giant cells, before they die, give rise to several cells with viable genomes via nuclear budding and asymmetric cytokinesis. This mode of cell division has been termed neosis and the immediate neotic offspring the Raju cells. The latter inherit genomic instability and transiently display stem cell properties in that they differentiate into tumor cells and display extended, but, limited MLS, at the end of which they enter senescent phase and can undergo secondary/tertiary neosis to produce the next generation of Raju cells. Neosis is repeated several times during tumor growth in a non-synchronized fashion, is the mode of origin of resistant tumor growth and contributes to tumor cell heterogeneity and continuity. The main event during neosis appears to be the production of mitotically viable daughter genome after epigenetic modulation from the non-viable polyploid genome of neosis mother cell (NMC. This leads to the growth of resistant tumor cells. Since during neosis, spindle checkpoint is not activated, this may give rise to aneuploidy. Thus, tumor cells also are destined to die due to

  18. p53-related apoptosis resistance and tumor suppression activity in UVB-induced premature senescent human skin fibroblasts.

    Science.gov (United States)

    Chen, Wenqi; Kang, Jian; Xia, Jiping; Li, Yanhua; Yang, Bo; Chen, Bin; Sun, Weiling; Song, Xiuzu; Xiang, Wenzhong; Wang, Xiaoyong; Wang, Fei; Wan, Yinsheng; Bi, Zhigang

    2008-05-01

    Chronic exposure to solar UV irradiation leads to photoaging, immunosuppression, and ultimately carcinogenesis. Cellular senescence is thought to play an important role in tumor suppression and apoptosis resistance. However, the relationships among stress-induced premature senescence (SIPS), tumorigenesis and apoptosis induced by UVB remain unknown. We developed a model of UVB-induced premature senescence in human skin fibroblasts (HSFs). After five repeated subcytotoxic UVB exposures at a dose of 10 mJ/cm2, the following biomarkers of senescence were markedly present: senescence-associated beta-galactosidase (SA beta-gal) activity, growth arrest, and the overexpression of senescence-associated genes. Firstly, there was an increase in the proportion of cells positive for SA beta-gal activity. Secondly, there was a loss of replicative potential as assessed by MTT assay. FACS analysis showed that UVB-stressed HSFs were blocked mostly in the G1 phase of the cell cycle, and replicative senescence, and protein expression of p53, p21(WAF-1) and p16(INK-4a) increased significantly. Thirdly, the mRNA levels of three senescence-associated genes, fibronectin, osteonectin and SM22, also increased. A real time PCR array to investigate the mRNA expression of p53-related genes involved in growth arrest, apoptosis and tumorigenesis indicated that p53, p21, p19, Hdm2, and Bax were up-regulated, and bcl, HIF-1alpha and VEGF were down-regulated. Collectively, our data suggest that UVB-induced SIPS plays an important role in p53-related apoptosis resistance and tumor suppression activity. PMID:18425358

  19. Preventive Effects of Epigallocatechin-3-O-Gallate against Replicative Senescence Associated with p53 Acetylation in Human Dermal Fibroblasts

    Directory of Open Access Journals (Sweden)

    Dong-Wook Han

    2012-01-01

    Full Text Available Considering the various pharmacological activities of epigallocatechin-3-O-gallate (EGCG including anticancer, and anti-inflammatory, antidiabetic, and so forth, relatively less attention has been paid to the antiaging effect of EGCG on primary cells. In this study, the preventive effects of EGCG against serial passage-induced senescence were investigated in primary cells including rat vascular smooth muscle cells (RVSMCs, human dermal fibroblasts (HDFs, and human articular chondrocytes (HACs. The involvement of Sirt1 and acetylated p53 was examined as an underlying mechanism for the senescence preventive activity of EGCG in HDFs. All cells were employed with the initial passage number (PN between 3 and 7. For inducing senescence, the cells were serially passaged at the predetermined times and intervals in the absence or presence of EGCG (50 or 100 μM. Serial passage-induced senescence in RVSMCs and HACs was able to be significantly prevented at 50 μM EGCG, while in HDFs, 100 μM EGCG could significantly prevent senescence and recover their cell cycle progression close to the normal level. Furthermore, EGCG was found to prevent serial passage- and H2O2-induced senescence in HDFs by suppressing p53 acetylation, but the Sirt1 activity was unaffected. In addition, proliferating HDFs showed similar cellular uptake of FITC-conjugated EGCG into the cytoplasm with their senescent counterparts but different nuclear translocation of it from them, which would partly account for the differential responses to EGCG in proliferating versus senescent cells. Taking these results into consideration, it is suggested that EGCG may be exploited to craft strategies for the development of an antiaging or age-delaying agent.

  20. Tocotrienol-Rich Fraction Prevents Cell Cycle Arrest and Elongates Telomere Length in Senescent Human Diploid Fibroblasts

    Directory of Open Access Journals (Sweden)

    Suzana Makpol

    2011-01-01

    Full Text Available This study determined the molecular mechanisms of tocotrienol-rich fraction (TRF in preventing cellular senescence of human diploid fibroblasts (HDFs. Primary culture of HDFs at various passages were incubated with 0.5 mg/mL TRF for 24 h. Telomere shortening with decreased telomerase activity was observed in senescent HDFs while the levels of damaged DNA and number of cells in G0/G1 phase were increased and S phase cells were decreased. Incubation with TRF reversed the morphology of senescent HDFs to resemble that of young cells with decreased activity of SA-β-gal, damaged DNA, and cells in G0/G1 phase while cells in the S phase were increased. Elongated telomere length and restoration of telomerase activity were observed in TRF-treated senescent HDFs. These findings confirmed the ability of tocotrienol-rich fraction in preventing HDFs cellular ageing by restoring telomere length and telomerase activity, reducing damaged DNA, and reversing cell cycle arrest associated with senescence.

  1. Dandelion Extracts Protect Human Skin Fibroblasts from UVB Damage and Cellular Senescence

    Directory of Open Access Journals (Sweden)

    Yafan Yang

    2015-01-01

    Full Text Available Ultraviolet (UV irradiation causes damage in skin by generating excessive reactive oxygen species (ROS and induction of matrix metalloproteinases (MMPs, leading to skin photoageing. Dandelion extracts have long been used for traditional Chinese medicine and native American medicine to treat cancers, hepatitis, and digestive diseases; however, less is known on the effects of dandelion extracts in skin photoageing. Here we found that dandelion leaf and flower extracts significantly protect UVB irradiation-inhibited cell viability when added before UVB irradiation or promptly after irradiation. Dandelion leaf and flower extracts inhibited UVB irradiation-stimulated MMP activity and ROS generation. Dandelion root extracts showed less action on protecting HDFs from UVB irradiation-induced MMP activity, ROS generation, and cell death. Furthermore, dandelion leaf and flower but not root extracts stimulated glutathione generation and glutathione reductase mRNA expression in the presence or absence of UVB irradiation. We also found that dandelion leaf and flower extracts help absorb UVB irradiation. In addition, dandelion extracts significantly protected HDFs from H2O2-induced cellular senescence. In conclusion, dandelion extracts especially leaf and flower extracts are potent protective agents against UVB damage and H2O2-induced cellular senescence in HDFs by suppressing ROS generation and MMP activities and helping UVB absorption.

  2. Dandelion Extracts Protect Human Skin Fibroblasts from UVB Damage and Cellular Senescence.

    Science.gov (United States)

    Yang, Yafan; Li, Shuangshuang

    2015-01-01

    Ultraviolet (UV) irradiation causes damage in skin by generating excessive reactive oxygen species (ROS) and induction of matrix metalloproteinases (MMPs), leading to skin photoageing. Dandelion extracts have long been used for traditional Chinese medicine and native American medicine to treat cancers, hepatitis, and digestive diseases; however, less is known on the effects of dandelion extracts in skin photoageing. Here we found that dandelion leaf and flower extracts significantly protect UVB irradiation-inhibited cell viability when added before UVB irradiation or promptly after irradiation. Dandelion leaf and flower extracts inhibited UVB irradiation-stimulated MMP activity and ROS generation. Dandelion root extracts showed less action on protecting HDFs from UVB irradiation-induced MMP activity, ROS generation, and cell death. Furthermore, dandelion leaf and flower but not root extracts stimulated glutathione generation and glutathione reductase mRNA expression in the presence or absence of UVB irradiation. We also found that dandelion leaf and flower extracts help absorb UVB irradiation. In addition, dandelion extracts significantly protected HDFs from H2O2-induced cellular senescence. In conclusion, dandelion extracts especially leaf and flower extracts are potent protective agents against UVB damage and H2O2-induced cellular senescence in HDFs by suppressing ROS generation and MMP activities and helping UVB absorption. PMID:26576225

  3. The profile of lysosomal exoglycosidases in replicative and stress-induced senescence in early passage human fibroblasts

    Directory of Open Access Journals (Sweden)

    Małgorzata Knaś

    2012-07-01

    Full Text Available The aim of the present study was to assess the profiles of the exoglycosidases: N-acetyl-β-hexosoaminidase, β glucuronidase and β galactosidase, α mannosidase and α fucosidase in fibroblast culture undergoing replicative and stress-induced senescence. Half of the cell culture was grown in normal conditions, without the stressor, and the other half of the cell was treated with 0.15 mM tert-butylhydroperoxide. The activities of total N-acetyl-β-hexosoaminidase as well as β glucuronidase in the cell lysate were determined in duplicates using the method of Marciniak et al. The activities of β galactosidase, α mannosidase and α fucosidase in the cell lysate were determined in duplicates using the method of Chatteriee et al. with the modification by Zwierz et al. The activities of the exoglycosidases examined, with the exception of β glucuronidase, showed a significant increase between individual days of the experiment in both non-stressed and stressed fibroblast cell culture. On each day of the experiment, in the cell lysate of stressed fibroblasts, the activities of exoglycosidases were significantly higher compared to the non-stressed cells. There were very strong correlations between SA-β-GAL staining and b galactosidase activity on individual days of the experiment in both non-stressed and stressed fibroblast cell culture. Replicative and stress-induced senescence results in significant changes to the level of lysosomal exoglycosidases, and results in enhanced lysosomal degradative capacity.

  4. Phenyl 2-pyridyl ketoxime induces cellular senescence-like alterations via nitric oxide production in human diploid fibroblasts.

    Science.gov (United States)

    Yang, Kyeong Eun; Jang, Hyun-Jin; Hwang, In-Hu; Chung, Young-Ho; Choi, Jong-Soon; Lee, Tae-Hoon; Chung, Yun-Jo; Lee, Min-Seung; Lee, Mi Young; Yeo, Eui-Ju; Jang, Ik-Soon

    2016-04-01

    Phenyl-2-pyridyl ketoxime (PPKO) was found to be one of the small molecules enriched in the extracellular matrix of near-senescent human diploid fibroblasts (HDFs). Treatment of young HDFs with PPKO reduced the viability of young HDFs in a dose- and time-dependent manner and resulted in senescence-associated β-galactosidase (SA-β-gal) staining and G2/M cell cycle arrest. In addition, the levels of some senescence-associated proteins, such as phosphorylated ERK1/2, caveolin-1, p53, p16(ink4a) , and p21(waf1) , were elevated in PPKO-treated cells. To monitor the effect of PPKO on cell stress responses, reactive oxygen species (ROS) production was examined by flow cytometry. After PPKO treatment, ROS levels transiently increased at 30 min but then returned to baseline at 60 min. The levels of some antioxidant enzymes, such as catalase, peroxiredoxin II and glutathione peroxidase I, were transiently induced by PPKO treatment. SOD II levels increased gradually, whereas the SOD I and III levels were biphasic during the experimental periods after PPKO treatment. Cellular senescence induced by PPKO was suppressed by chemical antioxidants, such as N-acetylcysteine, 2,2,6,6-tetramethylpiperidinyloxy, and L-buthionine-(S,R)-sulfoximine. Furthermore, PPKO increased nitric oxide (NO) production via inducible NO synthase (iNOS) in HDFs. In the presence of NOS inhibitors, such as L-NG-nitroarginine methyl ester and L-NG-monomethylarginine, PPKO-induced transient NO production and SA-β-gal staining were abrogated. Taken together, these results suggest that PPKO induces cellular senescence in association with transient ROS and NO production and the subsequent induction of senescence-associated proteins. PMID:26696133

  5. Cancer exosomes trigger fibroblast to myofibroblast differentiation.

    Science.gov (United States)

    Webber, Jason; Steadman, Robert; Mason, Malcolm D; Tabi, Zsuzsanna; Clayton, Aled

    2010-12-01

    There is a growing interest in the cell-cell communication roles in cancer mediated by secreted vesicles termed exosomes. In this study, we examined whether exosomes produced by cancer cells could transmit information to normal stromal fibroblasts and trigger a cellular response. We found that some cancer-derived exosomes could trigger elevated α-smooth muscle actin expression and other changes consistent with the process of fibroblast differentiation into myofibroblasts. We show that TGF-β is expressed at the exosome surface in association with the transmembrane proteoglycan betaglycan. Although existing in a latent state, this complex was fully functional in eliciting SMAD-dependent signaling. Inhibiting either signaling or betaglycan expression attenuated differentiation. While the kinetics and overall magnitude of the response were similar to that achieved with soluble TGF-β, we identified important qualitative differences unique to the exosomal route of TGF-β delivery, as exemplified by a significant elevation in fibroblast FGF2 production. This hitherto unknown trigger for instigating cellular differentiation in a distinctive manner has major implications for mechanisms underlying cancer-recruited stroma, fibrotic diseases, and wound-healing responses. PMID:21098712

  6. Acrolein-Exposed Normal Human Lung Fibroblasts in Vitro: Cellular Senescence, Enhanced Telomere Erosion, and Degradation of Werner’s Syndrome Protein

    OpenAIRE

    Jang, Jun-Ho; Bruse, Shannon; Huneidi, Salam; Schrader, Ronald M; Monick, Martha M.; Lin, Yong; Carter, A. Brent; Klingelhutz, Aloysius J.; Nyunoya, Toru

    2014-01-01

    Background: Acrolein is a ubiquitous environmental hazard to human health. Acrolein has been reported to activate the DNA damage response and induce apoptosis. However, little is known about the effects of acrolein on cellular senescence. Objectives: We examined whether acrolein induces cellular senescence in cultured normal human lung fibroblasts (NHLF). Methods: We cultured NHLF in the presence or absence of acrolein and determined the effects of acrolein on cell proliferative capacity, sen...

  7. Senescent cells in growing tumors: population dynamics and cancer stem cells

    OpenAIRE

    C.A.M. La Porta; Zapperi, S.; Sethna, J. P.

    2012-01-01

    Author Summary It is commonly believed that cell senescence – the loss of replicative capacity of cells – acts as a barrier for tumor growth. Here we follow the evolution of senescence markers in melanoma cells and find that while most cancer cells eventually turn senescent, this is at root irrelevant for the long-term growth rate of a tumor. To demonstrate this, we construct a mathematical population dynamics model incorporating cancer stem cells which is able to reproduce quantitatively the...

  8. Cultures of cancer patient's skin tissue fibroblast and radiosensitivity assay

    International Nuclear Information System (INIS)

    In order to test the radiosensitivity of normal skin tissue, the authors cultured cancer patient's skin tissue fibroblast, surviving fraction experiment was employed to provide data for understanding of the different radiosensitivity among the cancer patients, Method: cancer patient's skin tissue fibroblast were cultured in vitro by the way of tar's attachment, cells were irradiated by graded doses of γ-ray , cell dose response experiment was used to test the radiosensitivity of cell. Result: Cancer patient's skin fibroblast could be propagated and passaged by the method of culture in vitro. Radiosensitivity are different among the various cancer patient's skin tissue fibroblasts

  9. Senescent cells and their secretory phenotype as targets for cancer therapy

    NARCIS (Netherlands)

    Velarde, Michael C; Demaria, Marco; Campisi, Judith

    2013-01-01

    Cancer is a devastating disease that increases exponentially with age. Cancer arises from cells that proliferate in an unregulated manner, an attribute that is countered by cellular senescence. Cellular senescence is a potent tumor-suppressive process that halts the proliferation, essentially irreve

  10. Cancer-associated fibroblasts in hepatocellular carcinoma.

    Science.gov (United States)

    Kubo, Norio; Araki, Kenichiro; Kuwano, Hiroyuki; Shirabe, Ken

    2016-08-14

    The hepatic stellate cells in the liver are stimulated sustainably by chronic injury of the hepatocytes, activating myofibroblasts, which produce abundant collagen. Myofibroblasts are the major source of extracellular proteins during fibrogenesis, and may directly, or secreted products, contribute to carcinogenesis and tumor progression. Cancer-associated fibroblasts (CAFs) are one of the components of the tumor microenvironment that promote the proliferation and invasion of cancer cells by secreting various growth factors and cytokines. CAFs crosstalk with cancer cells stimulates tumor progression by creating a favorable microenvironment for progression, invasion, and metastasis through the epithelial-mesenchymal transition. Basic studies on CAFs have advanced, and the role of CAFs in tumors has been elucidated. In particular, for hepatocellular carcinoma, carcinogenesis from cirrhosis is a known fact, and participation of CAFs in carcinogenesis is supported. In this review, we discuss the current literature on the role of CAFs and CAF-related signaling in carcinogenesis, crosstalk with cancer cells, immunosuppressive effects, angiogenesis, therapeutic targets, and resistance to chemotherapy. The role of CAFs is important in cancer initiation and progression. CAFtargeted therapy may be effective for suppression not only of fibrosis but also cancer progression. PMID:27570421

  11. Inhibition of Mitochondrial Cytochrome c Release and Suppression of Caspases by Gamma-Tocotrienol Prevent Apoptosis and Delay Aging in Stress-Induced Premature Senescence of Skin Fibroblasts

    Directory of Open Access Journals (Sweden)

    Suzana Makpol

    2012-01-01

    Full Text Available In this study, we determined the molecular mechanism of γ-tocotrienol (GTT in preventing cellular aging by focusing on its anti-apoptotic effect in stress-induced premature senescence (SIPS model of human diploid fibroblasts (HDFs. Results obtained showed that SIPS exhibited senescent-phenotypic characteristic, increased expression of senescence-associated β-galactosidase (SA β-gal and promoted G0/G1 cell cycle arrest accompanied by shortening of telomere length with decreased telomerase activity. Both SIPS and senescent HDFs shared similar apoptotic changes such as increased Annexin V-FITC positive cells, increased cytochrome c release and increased activation of caspase-9 and caspase-3 (P<0.05. GTT treatment resulted in a significant reduction of Annexin V-FITC positive cells, inhibited cytochrome c release and decreased activation of caspase-9 and caspase-3 (P<0.05. Gene expression analysis showed that GTT treatment down regulated BAX mRNA, up-regulated BCL2A1 mRNA and decreased the ratio of Bax/Bcl-2 protein expression (P<0.05 in SIPS. These findings suggested that GTT inhibits apoptosis by modulating the upstream apoptosis cascade, causing the inhibition of cytochrome c release from the mitochondria with concomitant suppression of caspase-9 and caspase-3 activation. In conclusion, GTT delays cellular senescence of human diploid fibroblasts through the inhibition of intrinsic mitochondria-mediated pathway which involved the regulation of pro- and anti-apoptotic genes and proteins.

  12. miR-137 Modulates a Tumor Suppressor Network-Inducing Senescence in Pancreatic Cancer Cells

    Directory of Open Access Journals (Sweden)

    Mathieu Neault

    2016-03-01

    Full Text Available Activating K-Ras mutations occurs frequently in pancreatic cancers and is implicated in their development. Cancer-initiating events, such as oncogenic Ras activation, lead to the induction of cellular senescence, a tumor suppressor response. During senescence, the decreased levels of KDM4A lysine demethylase contribute to p53 activation, however, the mechanism by which KDM4A is downregulated is unknown. We show that miR-137 targets KDM4A mRNA during Ras-induced senescence and activates both p53 and retinoblastoma (pRb tumor suppressor pathways. Restoring the KDM4A expression contributed to bypass of miR-137-induced senescence and inhibition of endogenous miR-137 with an miRNA sponge-compromised Ras-induced senescence. miR-137 levels are significantly reduced in human pancreatic tumors, consistent with previous studies revealing a defective senescence response in this cancer type. Restoration of miR-137 expression inhibited proliferation and promoted senescence of pancreatic cancer cells. These results suggest that modulating levels of miR-137 may be important for triggering tumor suppressor networks in pancreatic cancer.

  13. Accelerated telomere shortening and replicative senescence in human fibroblasts overexpressing mutant and wild-type lamin A

    International Nuclear Information System (INIS)

    LMNA mutations are responsible for a variety of genetic disorders, including muscular dystrophy, lipodystrophy, and certain progeroid syndromes, notably Hutchinson-Gilford Progeria. Although a number of clinical features of these disorders are suggestive of accelerated aging, it is not known whether cells derived from these patients exhibit cellular phenotypes associated with accelerated aging. We examined a series of isogenic skin fibroblast lines transfected with LMNA constructs bearing known pathogenic point mutations or deletion mutations found in progeroid syndromes. Fibroblasts overexpressing mutant lamin A exhibited accelerated rates of loss of telomeres and shortened replicative lifespans, in addition to abnormal nuclear morphology. To our surprise, these abnormalities were also observed in lines overexpressing wild-type lamin A. Copy number variants are common in human populations; those involving LMNA, whether arising meiotically or mitotically, might lead to progeroid phenotypes. In an initial pilot study of 23 progeroid cases without detectable WRN or LMNA mutations, however, no cases of altered LMNA copy number were detected. Nevertheless, our findings raise a hypothesis that changes in lamina organization may cause accelerated telomere attrition, with different kinetics for overexpession of wild-type and mutant lamin A, which leads to rapid replicative senescence and progroid phenotypes

  14. CDK2 differentially controls normal cell senescence and cancer cell proliferation upon exposure to reactive oxygen species

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Chae Young; Lee, Seung-Min; Park, Sung Sup [Laboratory of Cell Signaling, Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahangno, Yusong, Daejeon 305-806 (Korea, Republic of); Kwon, Ki-Sun, E-mail: kwonks@kribb.re.kr [Laboratory of Cell Signaling, Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahangno, Yusong, Daejeon 305-806 (Korea, Republic of)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer H{sub 2}O{sub 2} differently adjusted senescence and proliferation in normal and cancer cells. Black-Right-Pointing-Pointer H{sub 2}O{sub 2} exposure transiently decreased PCNA levels in normal cells. Black-Right-Pointing-Pointer H{sub 2}O{sub 2} exposure transiently increased CDK2 activity in cancer cells. Black-Right-Pointing-Pointer p21{sup Cip1} is likely dispensable when H{sub 2}O{sub 2} induces senescence in normal cells. Black-Right-Pointing-Pointer Suggestively, CDK2 and PCNA play critical roles in H{sub 2}O{sub 2}-induced cell fate decision. -- Abstract: Reactive oxygen species modulate cell fate in a context-dependent manner. Sublethal doses of H{sub 2}O{sub 2} decreased the level of proliferating cell nuclear antigen (PCNA) in normal cells (including primary human dermal fibroblasts and IMR-90 cells) without affecting cyclin-dependent kinase 2 (CDK2) activity, leading to cell cycle arrest and subsequent senescence. In contrast, exposure of cancer cells (such as HeLa and MCF7 cells) to H{sub 2}O{sub 2} increased CDK2 activity with no accompanying change in the PCNA level, leading to cell proliferation. A CDK2 inhibitor, CVT-313, prevented H{sub 2}O{sub 2}-induced cancer cell proliferation. These results support the notion that the cyclin/CDK2/p21{sup Cip1}/PCNA complex plays an important role as a regulator of cell fate decisions.

  15. SIRT3 overexpression antagonizes high glucose accelerated cellular senescence in human diploid fibroblasts via the SIRT3–FOXO1 signaling pathway

    OpenAIRE

    Zhang, Bin; Cui, Shaoyuan; Bai, Xueyuan; Zhuo, Li; Sun, Xuefeng; Hong, Quan; Fu, Bo; Wang, Jianzhong; Chen, Xiangmei; Cai, Guangyan

    2013-01-01

    Sirtuin 3 (SIRT3) is one of the seven mammalian sirtuins, which are homologs of the yeast Sir2 gene. SIRT3 is the only sirtuin reported to be associated with human life span. Many recent studies have indicated that SIRT3 levels are elevated by exercise and caloric restriction, but whether SIRT3 influences cell senescence under stressed conditions in human diploid fibroblasts has not been established. Our data showed that expression of SIRT3 is elevated in human diploid fibroblasts under low g...

  16. Androgen Deprivation-Induced Senescence Promotes Outgrowth of Androgen-Refractory Prostate Cancer Cells

    OpenAIRE

    Burton, Dominick G. A.; Giribaldi, Maria G.; Anisleidys Munoz; Katherine Halvorsen; Asmita Patel; Merce Jorda; Carlos Perez-Stable; Priyamvada Rai

    2013-01-01

    Androgen deprivation (AD) is an effective method for initially suppressing prostate cancer (PC) progression. However, androgen-refractory PC cells inevitably emerge from the androgen-responsive tumor, leading to incurable disease. Recent studies have shown AD induces cellular senescence, a phenomenon that is cell-autonomously tumor-suppressive but which confers tumor-promoting adaptations that can facilitate the advent of senescence-resistant malignant cell populations. Because androgen-refra...

  17. Dandelion Extracts Protect Human Skin Fibroblasts from UVB Damage and Cellular Senescence

    OpenAIRE

    Yafan Yang; Shuangshuang Li

    2015-01-01

    Ultraviolet (UV) irradiation causes damage in skin by generating excessive reactive oxygen species (ROS) and induction of matrix metalloproteinases (MMPs), leading to skin photoageing. Dandelion extracts have long been used for traditional Chinese medicine and native American medicine to treat cancers, hepatitis, and digestive diseases; however, less is known on the effects of dandelion extracts in skin photoageing. Here we found that dandelion leaf and flower extracts significantly protect U...

  18. LIF Mediates Proinvasive Activation of Stromal Fibroblasts in Cancer

    Directory of Open Access Journals (Sweden)

    Jean Albrengues

    2014-06-01

    Full Text Available Signaling crosstalk between tumor cells and fibroblasts confers proinvasive properties to the tumor microenvironment. Here, we identify leukemia inhibitory factor (LIF as a tumor promoter that mediates proinvasive activation of stromal fibroblasts independent of alpha-smooth muscle actin (α-SMA expression. We demonstrate that a pulse of transforming growth factor β (TGF-β establishes stable proinvasive fibroblast activation by inducing LIF production in both fibroblasts and tumor cells. In fibroblasts, LIF mediates TGF-β-dependent actomyosin contractility and extracellular matrix remodeling, which results in collective carcinoma cell invasion in vitro and in vivo. Accordingly, carcinomas from multiple origins and melanomas display strong LIF upregulation, which correlates with dense collagen fiber organization, cancer cell collective invasion, and poor clinical outcome. Blockade of JAK activity by Ruxolitinib (JAK inhibitor counteracts fibroblast-dependent carcinoma cell invasion in vitro and in vivo. These findings establish LIF as a proinvasive fibroblast producer independent of α-SMA and may open novel therapeutic perspectives for patients with aggressive primary tumors.

  19. Ets2 in tumor fibroblasts promotes angiogenesis in breast cancer.

    Directory of Open Access Journals (Sweden)

    Julie A Wallace

    Full Text Available Tumor fibroblasts are active partners in tumor progression, but the genes and pathways that mediate this collaboration are ill-defined. Previous work demonstrates that Ets2 function in stromal cells significantly contributes to breast tumor progression. Conditional mouse models were used to study the function of Ets2 in both mammary stromal fibroblasts and epithelial cells. Conditional inactivation of Ets2 in stromal fibroblasts in PyMT and ErbB2 driven tumors significantly reduced tumor growth, however deletion of Ets2 in epithelial cells in the PyMT model had no significant effect. Analysis of gene expression in fibroblasts revealed a tumor- and Ets2-dependent gene signature that was enriched in genes important for ECM remodeling, cell migration, and angiogenesis in both PyMT and ErbB2 driven-tumors. Consistent with these results, PyMT and ErbB2 tumors lacking Ets2 in fibroblasts had fewer functional blood vessels, and Ets2 in fibroblasts elicited changes in gene expression in tumor endothelial cells consistent with this phenotype. An in vivo angiogenesis assay revealed the ability of Ets2 in fibroblasts to promote blood vessel formation in the absence of tumor cells. Importantly, the Ets2-dependent gene expression signatures from both mouse models were able to distinguish human breast tumor stroma from normal stroma, and correlated with patient outcomes in two whole tumor breast cancer data sets. The data reveals a key function for Ets2 in tumor fibroblasts in signaling to endothelial cells to promote tumor angiogenesis. The results highlight the collaborative networks that orchestrate communication between stromal cells and tumor cells, and suggest that targeting tumor fibroblasts may be an effective strategy for developing novel anti-angiogenic therapies.

  20. Ets2 in tumor fibroblasts promotes angiogenesis in breast cancer.

    Science.gov (United States)

    Wallace, Julie A; Li, Fu; Balakrishnan, Subhasree; Cantemir-Stone, Carmen Z; Pecot, Thierry; Martin, Chelsea; Kladney, Raleigh D; Sharma, Sudarshana M; Trimboli, Anthony J; Fernandez, Soledad A; Yu, Lianbo; Rosol, Thomas J; Stromberg, Paul C; Lesurf, Robert; Hallett, Michael; Park, Morag; Leone, Gustavo; Ostrowski, Michael C

    2013-01-01

    Tumor fibroblasts are active partners in tumor progression, but the genes and pathways that mediate this collaboration are ill-defined. Previous work demonstrates that Ets2 function in stromal cells significantly contributes to breast tumor progression. Conditional mouse models were used to study the function of Ets2 in both mammary stromal fibroblasts and epithelial cells. Conditional inactivation of Ets2 in stromal fibroblasts in PyMT and ErbB2 driven tumors significantly reduced tumor growth, however deletion of Ets2 in epithelial cells in the PyMT model had no significant effect. Analysis of gene expression in fibroblasts revealed a tumor- and Ets2-dependent gene signature that was enriched in genes important for ECM remodeling, cell migration, and angiogenesis in both PyMT and ErbB2 driven-tumors. Consistent with these results, PyMT and ErbB2 tumors lacking Ets2 in fibroblasts had fewer functional blood vessels, and Ets2 in fibroblasts elicited changes in gene expression in tumor endothelial cells consistent with this phenotype. An in vivo angiogenesis assay revealed the ability of Ets2 in fibroblasts to promote blood vessel formation in the absence of tumor cells. Importantly, the Ets2-dependent gene expression signatures from both mouse models were able to distinguish human breast tumor stroma from normal stroma, and correlated with patient outcomes in two whole tumor breast cancer data sets. The data reveals a key function for Ets2 in tumor fibroblasts in signaling to endothelial cells to promote tumor angiogenesis. The results highlight the collaborative networks that orchestrate communication between stromal cells and tumor cells, and suggest that targeting tumor fibroblasts may be an effective strategy for developing novel anti-angiogenic therapies. PMID:23977064

  1. Biallelic Mutations in p16INK4a Confer Resistance to Ras- and Ets-Induced Senescence in Human Diploid Fibroblasts

    OpenAIRE

    Huot, Thomas J.; Rowe, Janice; Harland, Mark; Drayton, Sarah; Brookes, Sharon; Gooptu, Chandra; Purkis, Patricia; Fried, Mike; Bataille, Veronique; Hara, Eiji; Newton-Bishop, Julia; Peters, Gordon

    2002-01-01

    The INK4a/ARF tumor suppressor locus is implicated in the senescence-like growth arrest provoked by oncogenic Ras in primary cells. INK4a and ARF are distinct proteins encoded by transcripts in which a shared exon is decoded in alternative reading frames. Here we analyze dermal fibroblasts (designated Q34) from an individual carrying independent missense mutations in each copy of the common exon. Both mutations alter the amino acid sequence of INK4a and functionally impair the protein, althou...

  2. Overexpression of the novel senescence marker β-galactosidase (GLB1 in prostate cancer predicts reduced PSA recurrence.

    Directory of Open Access Journals (Sweden)

    Jennifer Wagner

    Full Text Available Senescence is a terminal growth arrest that functions as a tumor suppressor in aging and precancerous cells and is a response to selected anticancer compounds. Lysosomal-β-galactosidase (GLB1 hydrolyzes β-galactose from glycoconjugates and is the origin of senescence-associated β-gal activity (SA-β-gal. Using a new GLB1 antibody, senescence biology was investigated in prostate cancer (PCa tissues.In vitro characterization of GLB1 was determined in primary prostate epithelial cell cultures passaged to replicative senescence and in therapy-induced senescence in PCa lines using chemotherapeutic agents. FFPE tissue microarrays were subjected to immunofluorescent staining for GLB1, Ki67 and HP1γ and automated quantitative imaging initially using AQUA in exploratory samples and Vectra in a validation series.GLB1 expression accumulates in replicative and induced senescence and correlates with senescent morphology and P16 (CDKN2 expression. In tissue arrays, quantitative imaging detects increased GLB1 expression in high-grade prostatic intraepithelial neoplasia (HGPIN, known to contain senescent cells, and cancer compared to benign prostate tissues (p<0.01 and senescent cells contain low Ki67 and elevated HP1γ. Within primary tumors, elevated GLB1 associates with lower T stage (p=0.01, localized versus metastatic disease (p=0.0003 and improved PSA-free survival (p=0.03. Increased GLB1 stratifies better PSA-free survival in intermediate grade PCa (0.01. Tissues that elaborate higher GLB1 display increased uniformity of expression.Increased GLB1 is a valuable marker in formalin-fixed paraffin-embedded (FFPE tissues for the senescence-like phenotype and associates with improved cancer outcomes. This protein addresses a lack of senescence markers and should be applicable to study the biologic role of senescence in other cancers.

  3. Low power laser effects in cancer cells and fibroblasts submitted the ionizing radiation

    International Nuclear Information System (INIS)

    Cancer is considered a public health problem worldwide. According to Brazil's the National Cancer Institute (INCA), 576,000 new cases of cancer were estimated for 2015 in Brazil, representing the second leading cause of death. Radiotherapy may be a treatment to several of types of cancer, frequently using ionizing radiation to eradicate or prevent the proliferation of tumor cells. This treatment, however, can lead to death of non-tumor cells around in irradiated tissue. Given this, adjuvant therapies that can minimize the side effects of ionizing radiation are of extremely importance. In this context, low power laser (LPL) may be an alternative to modulate the response of healthy cells to ionizing radiation. In this study, cells of human gingival fibroblasts (FMM1) and breast cancer (MDAMB- 231) were exposed to gamma radiation at doses of 2.5 and 10 Gy. After twenty-four hours, cell were irradiated with LPL ( λ= 660 nm, 40 mW and total area of 0.04 cm²) with energy densities of 30, 60, 90, 120 and 150 J/cm². The cell viability was measured during four days, using the trypan blue technique. The influence of LPL on the cell cycle and on expression of the nuclear antigen of cellular proliferation (PCNA) was evaluated by flow cytometry. The expression of β-Galactosidase was the chosen method to assess cell senescence. Considering our adopted parameters, and focusing on the non-tumor cells, we have observed an increase in: 1) cell viability; 2) cell population in phases S and G2/M cell cycle; 3) PCNA expression with decrease in senescence. No alterations were observed in the cell viability, with greater population in phases S and G2/M cell cycle, while the number of senescent cells and the expression of PCNA were decreased. Therefore, we have concluded that the LPL promoted effects on both cell lineages, with increased cell viability on FMM1 cells, whether cancer cells maintained a decreased proliferation. (author)

  4. Biallelic mutations in p16(INK4a) confer resistance to Ras- and Ets-induced senescence in human diploid fibroblasts.

    Science.gov (United States)

    Huot, Thomas J; Rowe, Janice; Harland, Mark; Drayton, Sarah; Brookes, Sharon; Gooptu, Chandra; Purkis, Patricia; Fried, Mike; Bataille, Veronique; Hara, Eiji; Newton-Bishop, Julia; Peters, Gordon

    2002-12-01

    The INK4a/ARF tumor suppressor locus is implicated in the senescence-like growth arrest provoked by oncogenic Ras in primary cells. INK4a and ARF are distinct proteins encoded by transcripts in which a shared exon is decoded in alternative reading frames. Here we analyze dermal fibroblasts (designated Q34) from an individual carrying independent missense mutations in each copy of the common exon. Both mutations alter the amino acid sequence of INK4a and functionally impair the protein, although they do so to different degrees. Only one of the mutations affects the sequence of ARF, causing an apparently innocuous change near its carboxy terminus. Unlike normal human fibroblasts, Q34 cells are not permanently arrested by Ras or its downstream effectors Ets1 and Ets2. Moreover, ectopic Ras enables the cells to grow as anchorage-independent colonies, and in relatively young Q34 cells anchorage independence can be achieved without addition of telomerase or perturbation of the p53 pathway. Whereas ARF plays the principal role in Ras-induced arrest of mouse fibroblasts, our data imply that INK4a assumes this role in human fibroblasts. PMID:12417717

  5. Suppression of the senescence-associated secretory phenotype (SASP) in human fibroblasts using small molecule inhibitors of p38 MAP kinase and MK2.

    Science.gov (United States)

    Alimbetov, Dauren; Davis, Terence; Brook, Amy J C; Cox, Lynne S; Faragher, Richard G A; Nurgozhin, Talgat; Zhumadilov, Zhaxybay; Kipling, David

    2016-04-01

    Senescent cells show an altered secretome profile termed the senescence-associated secretory phenotype (SASP). There is an increasing body of evidence that suggests that the accumulation of SASP-positive senescent cells in humans is partially causal in the observed shift to a low-level pro-inflammatory state in aged individuals. This in turn suggests the SASP as a possible therapeutic target to ameliorate inflammatory conditions in the elderly, and thus a better understanding of the signalling pathways underlying the SASP are required. Prior studies using the early generation p38 MAPK inhibitor SB203580 indicated that p38 signalling was required for the SASP. In this study, we extend these observations using two next-generation p38 inhibitors (UR-13756 and BIRB 796) that have markedly improved selectivity and specificity compared to SB203580, to strengthen the evidence that the SASP is p38-dependent in human fibroblasts. BIRB 796 has an efficacy and toxicity profile that has allowed it to reach Phase III clinical trials, suggesting its possible use to suppress the SASP in vivo. We also demonstrate for the first time a requirement for signalling through the p38 downstream MK2 kinase in the regulation of the SASP using two MK2 inhibitors. Finally, we demonstrate that a commercially-available multiplex cytokine assay technology can be used to detect SASP components in the conditioned medium of cultured fibroblasts from both young and elderly donors. This assay is a high-throughput, multiplex microtitre-based assay system that is highly sensitive, with very low sample requirements, allowing it to be used for low-volume human biological fluids. Our initial studies using existing multiplex plates form the basis for a "SASP signature" assay that could be used as a high-throughput system in a clinical study setting. Our findings therefore provide important steps towards the study of, and intervention in, the SASP in human ageing and age-related disease. PMID:26400758

  6. Cathelicidin suppresses colon cancer development by inhibition of cancer associated fibroblasts

    Directory of Open Access Journals (Sweden)

    Cheng M

    2014-12-01

    Full Text Available Michelle Cheng,1,* Samantha Ho,1,* Jun Hwan Yoo,1,2,* Deanna Hoang-Yen Tran,1,* Kyriaki Bakirtzi,1 Bowei Su,1 Diana Hoang-Ngoc Tran,1 Yuzu Kubota,1 Ryan Ichikawa,1 Hon Wai Koon1 1Center for Inflammatory Bowel Diseases, Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA; 2Digestive Disease Center, CHA University Bundang Medical Center, Seongnam, Republic of Korea *These authors share co-first authorship Background: Cathelicidin (LL-37 in humans and mCRAMP in mice represents a family of endogenous antimicrobial and anti-inflammatory peptides. Cancer-associated fibroblasts can promote the proliferation of colon cancer cells and growth of colon cancer tumors. Methods: We examined the role of cathelicidin in the development of colon cancer, using subcutaneous human HT-29 colon-cancer-cell-derived tumor model in nude mice and azoxymethane- and dextran sulfate-mediated colon cancer model in C57BL/6 mice. We also determined the indirect antitumoral mechanism of cathelicidin via the inhibition of epithelial–mesenchymal transition (EMT of colon cancer cells and fibroblast-supported colon cancer cell proliferation. Results: Intravenous administration of cathelicidin expressing adeno-associated virus significantly reduced the size of tumors, tumor-derived collagen expression, and tumor-derived fibroblast expression in HT-29-derived subcutaneous tumors in nude mice. Enema administration of the mouse cathelicidin peptide significantly reduced the size and number of colonic tumors in azoxymethane- and dextran sulfate-treated mice without inducing apoptosis in tumors and the adjacent normal colonic tissues. Cathelicidin inhibited the collagen expression and vimentin-positive fibroblast expression in colonic tumors. Cathelicidin did not directly affect HT-29 cell viability, but did significantly reduce tumor growth factor-ß1-induced EMT of colon cancer cells. Media conditioned by the

  7. Identification and characterization of secretory proteins during ionizing radiation-induced premature senescence

    International Nuclear Information System (INIS)

    Cellular senescence was first described by Hayflick and Moorhead in 1961 who observed that cultures of normal human fibroblasts had a limited replicative potential and eventually became irreversibly arrest. The majority of senescent cells assume a characteristic flattened and enlarged morphological change, senescence associated β alactosidase positivity. Recently a large number of molecular phenotypes such as changes in gene expression, protein processing and chromatin organization have been also described. In contrast to apoptosis, senescence does not destroy the cells but leaves them metabolically and synthetically active and therefore able to affect their microenvironment. In particular, senescent fibroblasts and some cancer cells were found to secrete proteins with known or putative tumor-promoting functions such as growth factors or proteolytic enzymes. However, the knowledge about secreted proteins from senescent tumor cells and their functions to surrounding cells is still lacking. In this study, changes of senescence associated secretory protein expression profile were observed in MCF7 human breast cancer cells exposed to gamma-ray radiation using two dimensional electrophoresis. Also, we identified up-regulated secretory proteins during ionizing radiation-induced cellular senescence. Here, we show that senescent human breast cancer MCF7 cells promote the proliferation, invasion and migration of neighboring cells

  8. Identification and characterization of secretory proteins during ionizing radiation-induced premature senescence

    Energy Technology Data Exchange (ETDEWEB)

    Han, Na Kyung; Hong, Mi Na; Jung, Seung Hee; Kang, Kyoung Ah; Lee, Jae Seon [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Chi, Seong Gil [Korea University, Seoul (Korea, Republic of)

    2011-05-15

    Cellular senescence was first described by Hayflick and Moorhead in 1961 who observed that cultures of normal human fibroblasts had a limited replicative potential and eventually became irreversibly arrest. The majority of senescent cells assume a characteristic flattened and enlarged morphological change, senescence associated {beta} alactosidase positivity. Recently a large number of molecular phenotypes such as changes in gene expression, protein processing and chromatin organization have been also described. In contrast to apoptosis, senescence does not destroy the cells but leaves them metabolically and synthetically active and therefore able to affect their microenvironment. In particular, senescent fibroblasts and some cancer cells were found to secrete proteins with known or putative tumor-promoting functions such as growth factors or proteolytic enzymes. However, the knowledge about secreted proteins from senescent tumor cells and their functions to surrounding cells is still lacking. In this study, changes of senescence associated secretory protein expression profile were observed in MCF7 human breast cancer cells exposed to gamma-ray radiation using two dimensional electrophoresis. Also, we identified up-regulated secretory proteins during ionizing radiation-induced cellular senescence. Here, we show that senescent human breast cancer MCF7 cells promote the proliferation, invasion and migration of neighboring cells

  9. Induction of premature senescence by single and fractionated irradiation in human cancer cell line and xenografted mice model

    International Nuclear Information System (INIS)

    Radiation therapy (RT) is one of the best therapeutic strategies for cancer treatment. The cellular responses to ionizing radiation (IR) are varied ranging from cellular senescence to apoptotic cell death. To increase the efficacy of IR treatment is a major issue of radiation biology. From the point of view, the induction of premature senescence using the therapeutic dose of IR could be a promising treatment for tumors. The aim of this study is whether the premature senescence could contribute to cancer treatment by irradiation

  10. ATM-deficient human fibroblast cells are resistant to low levels of DNA double-strand break induced apoptosis and subsequently undergo drug-induced premature senescence

    International Nuclear Information System (INIS)

    Highlights: ► A-T cells were not hypersensitive to low levels of DNA DSBs. ► A-T cells have enhanced Akt but defect in activation of p53 and apoptotic proteins. ► A-T cells underwent premature senescence after DNA damage accumulated. ► Chemotherapeutic effect in cancer therapy may be associated with premature senescence. -- Abstract: DNA DSBs are induced by IR or radiomimetic drugs such as doxorubicin. It has been indicated that cells from ataxia-telangiectasia patients are highly sensitive to radiation due to defects in DNA repair, but whether they have impairment in apoptosis has not been fully elucidated. A-T cells showed increased sensitivity to high levels of DNA damage, however, they were more resistant to low doses. Normal cells treated with combination of KU55933, a specific ATM kinase inhibitor, and doxorubicin showed increased resistance as they do in a similar manner to A-T cells. A-T cells have higher viability but more DNA breaks, in addition, the activations of p53 and apoptotic proteins (Bax and caspase-3) were deficient, but Akt expression was enhanced. A-T cells subsequently underwent premature senescence after treatment with a low dose of doxorubicin, which was confirmed by G2 accumulation, senescent morphology, and SA-β-gal positive until 15 days repair incubation. Finally, A-T cells are radio-resistant at low doses due to its defectiveness in detecting DNA damage and apoptosis, but the accumulation of DNA damage leads cells to premature senescence.

  11. ATM-deficient human fibroblast cells are resistant to low levels of DNA double-strand break induced apoptosis and subsequently undergo drug-induced premature senescence

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jun; Jo, Yong Hwa; Cho, Chang Hoon; Choe, Wonchae; Kang, Insug; Baik, Hyung Hwan [Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, 26 Kyunghee-daero, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Yoon, Kyung-Sik, E-mail: sky9999@khu.ac.kr [Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, 26 Kyunghee-daero, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of)

    2013-01-04

    Highlights: Black-Right-Pointing-Pointer A-T cells were not hypersensitive to low levels of DNA DSBs. Black-Right-Pointing-Pointer A-T cells have enhanced Akt but defect in activation of p53 and apoptotic proteins. Black-Right-Pointing-Pointer A-T cells underwent premature senescence after DNA damage accumulated. Black-Right-Pointing-Pointer Chemotherapeutic effect in cancer therapy may be associated with premature senescence. -- Abstract: DNA DSBs are induced by IR or radiomimetic drugs such as doxorubicin. It has been indicated that cells from ataxia-telangiectasia patients are highly sensitive to radiation due to defects in DNA repair, but whether they have impairment in apoptosis has not been fully elucidated. A-T cells showed increased sensitivity to high levels of DNA damage, however, they were more resistant to low doses. Normal cells treated with combination of KU55933, a specific ATM kinase inhibitor, and doxorubicin showed increased resistance as they do in a similar manner to A-T cells. A-T cells have higher viability but more DNA breaks, in addition, the activations of p53 and apoptotic proteins (Bax and caspase-3) were deficient, but Akt expression was enhanced. A-T cells subsequently underwent premature senescence after treatment with a low dose of doxorubicin, which was confirmed by G2 accumulation, senescent morphology, and SA-{beta}-gal positive until 15 days repair incubation. Finally, A-T cells are radio-resistant at low doses due to its defectiveness in detecting DNA damage and apoptosis, but the accumulation of DNA damage leads cells to premature senescence.

  12. Knocking down p53 with siRNA does not affect the overexpression of p21WAF-1 after exposure of IMR-90 hTERT fibroblasts to a sublethal concentration of H2O2 leading to premature senescence.

    Science.gov (United States)

    Zdanov, Stephanie; Debacq-Chainiaux, Florence; Toussaint, Olivier

    2007-04-01

    Premature senescence of IMR-90 human diploid fibroblasts (HDFs) expressing telomerase was induced by exposure to sublethal concentration of H(2)O(2), with appearance of several biomarkers of cellular senescence like enlarged cell shape, senescence-associated beta-galactosidase (SA ss-gal) activity, and cell cycle arrest. The induction of stress-induced premature senescence (SIPS) was associated with a transient increase in DNA-binding activity of p53 and an increased expression of p21(WAF-1). p53 small interferent RNA (siRNA) affected the basal level of p21(WAF-1) mRNA but did not affect the overexpression of p21(WAF-1) after stress. This siRNA approach confirms previous results obtained with other methods. PMID:17460194

  13. Androgen depletion induces senescence in prostate cancer cells through down-regulation of Skp2

    Czech Academy of Sciences Publication Activity Database

    Pernicová, Zuzana; Slabáková, Eva; Kharaishvili, G.; Bouchal, J.; Král, M.; Kunická, Z.; Machala, M.; Kozubík, Alois; Souček, Karel

    2011-01-01

    Roč. 13, č. 6 (2011), s. 526-536. ISSN 1522-8002 R&D Projects: GA ČR(CZ) GA310/07/0961; GA MZd NS9600; GA MZd NS9956 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : prostate cancer * senescence * Skp2 Subject RIV: BO - Biophysics Impact factor: 5.946, year: 2011

  14. Autophagy and cellular senescence mediated by Sox2 suppress malignancy of cancer cells.

    Directory of Open Access Journals (Sweden)

    Yong-Yeon Cho

    Full Text Available Autophagy is a critical cellular process required for maintaining cellular homeostasis in health and disease states, but the molecular mechanisms and impact of autophagy on cancer is not fully understood. Here, we found that Sox2, a key transcription factor in the regulation of the "stemness" of embryonic stem cells and induced-pluripotent stem cells, strongly induced autophagic phenomena, including intracellular vacuole formation and lysosomal activation in colon cancer cells. The activation occurred through Sox2-mediated ATG10 gene expression and resulted in the inhibition of cell proliferation and anchorage-independent colony growth ex vivo and tumor growth in vivo. Further, we found that Sox2-induced-autophagy enhanced cellular senescence by up-regulating tumor suppressors or senescence factors, including p16(INK4a, p21 and phosphorylated p53 (Ser15. Notably, knockdown of ATG10 in Sox2-expressing colon cancer cells restored cancer cell properties. Taken together, our results demonstrated that regulation of autophagy mediated by Sox2 is a mechanism-driven novel strategy to treat human colon cancers.

  15. Curcumin-treated cancer cells show mitotic disturbances leading to growth arrest and induction of senescence phenotype.

    Science.gov (United States)

    Mosieniak, Grażyna; Sliwinska, Małgorzata A; Przybylska, Dorota; Grabowska, Wioleta; Sunderland, Piotr; Bielak-Zmijewska, Anna; Sikora, Ewa

    2016-05-01

    Cellular senescence is recognized as a potent anticancer mechanism that inhibits carcinogenesis. Cancer cells can also undergo senescence upon chemo- or radiotherapy. Curcumin, a natural polyphenol derived from the rhizome of Curcuma longa, shows anticancer properties both in vitro and in vivo. Previously, we have shown that treatment with curcumin leads to senescence of human cancer cells. Now we identified the molecular mechanism underlying this phenomenon. We observed a time-dependent accumulation of mitotic cells upon curcumin treatment. The time-lapse analysis proved that those cells progressed through mitosis for a significantly longer period of time. A fraction of cells managed to divide or undergo mitotic slippage and then enter the next phase of the cell cycle. Cells arrested in mitosis had an improperly formed mitotic spindle and were positive for γH2AX, which shows that they acquired DNA damage during prolonged mitosis. Moreover, the DNA damage response pathway was activated upon curcumin treatment and the components of this pathway remained upregulated while cells were undergoing senescence. Inhibition of the DNA damage response decreased the number of senescent cells. Thus, our studies revealed that the induction of cell senescence upon curcumin treatment resulted from aberrant progression through the cell cycle. Moreover, the DNA damage acquired by cancer cells, due to mitotic disturbances, activates an important molecular mechanism that determines the potential anticancer activity of curcumin. PMID:26916504

  16. Cancer Associated Fibroblasts and Tumor Growth: Focus on Multiple Myeloma

    Energy Technology Data Exchange (ETDEWEB)

    De Veirman, Kim, E-mail: kdeveirm@vub.ac.be [Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel (VUB), Brussels 1090 (Belgium); Rao, Luigia [Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel (VUB), Brussels 1090 (Belgium); Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine, University of Bari Medical School, Bari I-70124 (Italy); De Bruyne, Elke; Menu, Eline; Van Valckenborgh, Els [Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel (VUB), Brussels 1090 (Belgium); Van Riet, Ivan [Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel (VUB), Brussels 1090 (Belgium); Stem Cell Laboratory, Division of Clinical Hematology, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels 1090 (Belgium); Frassanito, Maria Antonia [Department of Biomedical Sciences and Human Oncology, Section of General Pathology, University of Bari Medical School, Bari I-70124 (Italy); Di Marzo, Lucia; Vacca, Angelo [Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine, University of Bari Medical School, Bari I-70124 (Italy); Vanderkerken, Karin, E-mail: kdeveirm@vub.ac.be [Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel (VUB), Brussels 1090 (Belgium)

    2014-06-27

    Cancer associated fibroblasts (CAFs) comprise a heterogeneous population that resides within the tumor microenvironment. They actively participate in tumor growth and metastasis by production of cytokines and chemokines, and the release of pro-inflammatory and pro-angiogenic factors, creating a more supportive microenvironment. The aim of the current review is to summarize the origin and characteristics of CAFs, and to describe the role of CAFs in tumor progression and metastasis. Furthermore, we focus on the presence of CAFs in hypoxic conditions in relation to multiple myeloma disease.

  17. Cancer Associated Fibroblasts and Tumor Growth: Focus on Multiple Myeloma

    International Nuclear Information System (INIS)

    Cancer associated fibroblasts (CAFs) comprise a heterogeneous population that resides within the tumor microenvironment. They actively participate in tumor growth and metastasis by production of cytokines and chemokines, and the release of pro-inflammatory and pro-angiogenic factors, creating a more supportive microenvironment. The aim of the current review is to summarize the origin and characteristics of CAFs, and to describe the role of CAFs in tumor progression and metastasis. Furthermore, we focus on the presence of CAFs in hypoxic conditions in relation to multiple myeloma disease

  18. Identification of Secreted Proteins from Ionizing Radiation-Induced Senescent MCF7 Cells Using Comparative Proteomics

    International Nuclear Information System (INIS)

    Cellular senescence was first described by Hayflick and Moorhead in 1961 who observed that cultures of normal human fibroblasts had a limited replicative potential and eventually became irreversibly arrest. The majority of senescent cells assume a characteristic flattened and enlarged morphological change, senescence associated β-galactosidase positivity and over the years a large number of molecular phenotypes have been described, such as changes in gene expression, protein processing and chromatin organization. In contrast to apoptosis, senescence does not destroy the cells but leaves them metabolically and synthetically active and therefore able to affect their microenvironment. In particular, senescent fibroblasts and some cancer cells were found to secrete proteins with known or putative tumor-promoting functions such as growth factors or proteolytic enzymes. However, the knowledge about secreted proteins from senescent tumor cells and their functions to surrounding cells is still lacking. In this study, changes of senescence-associated secretory protein expression profile were observed in MCF7 human breast cancer cells exposed to gamma-ray radiation using two dimensional electrophoresis. Also, we identified up-regulated secretory proteins during ionizing radiation-induced cellular senescence

  19. Identification of Secreted Proteins from Ionizing Radiation-Induced Senescent MCF7 Cells Using Comparative Proteomics

    Energy Technology Data Exchange (ETDEWEB)

    Han, Na Kyung; Kim, Han Na; Hong, Mi Na; Park, Su Min; Lee, Jae Seon [Korea Institue of Radiological and Medical Sciences, Seoul (Korea, Republic of); Chi, Seong Gil [Korea University, Seoul (Korea, Republic of)

    2010-05-15

    Cellular senescence was first described by Hayflick and Moorhead in 1961 who observed that cultures of normal human fibroblasts had a limited replicative potential and eventually became irreversibly arrest. The majority of senescent cells assume a characteristic flattened and enlarged morphological change, senescence associated beta-galactosidase positivity and over the years a large number of molecular phenotypes have been described, such as changes in gene expression, protein processing and chromatin organization. In contrast to apoptosis, senescence does not destroy the cells but leaves them metabolically and synthetically active and therefore able to affect their microenvironment. In particular, senescent fibroblasts and some cancer cells were found to secrete proteins with known or putative tumor-promoting functions such as growth factors or proteolytic enzymes. However, the knowledge about secreted proteins from senescent tumor cells and their functions to surrounding cells is still lacking. In this study, changes of senescence-associated secretory protein expression profile were observed in MCF7 human breast cancer cells exposed to gamma-ray radiation using two dimensional electrophoresis. Also, we identified up-regulated secretory proteins during ionizing radiation-induced cellular senescence

  20. Argentatin B Inhibits Proliferation of Prostate and Colon Cancer Cells by Inducing Cell Senescence

    Directory of Open Access Journals (Sweden)

    Ela Alcántara-Flores

    2015-11-01

    Full Text Available Argentatin B has been shown to inhibit the growth of colon HCT-15, and prostate PC-3 cancer cells. However, the mechanism by which argentatin B inhibits cell proliferation is still unknown. We aimed to investigate the mechanism by which argentatin B inhibits cell proliferation. The cell cycle was studied by flow cytometry. Apoptosis was evaluated by Annexin-V-Fluos, and Hoechst 33342 dye staining. Cell senescence was evaluated by proliferation tests, and staining for SA-β-galactosidase. Senescence-related proteins (PCNA, p21, and p27 were analyzed by Western blotting. Potential toxicity of argentatin B was evaluated in CD-1 mice. Its effect on tumor growth was tested in a HCT-15 and PC-3 xenograft model. Argentatin B induced an increment of cells in sub G1, but did not produce apoptosis. Proliferation of both cell lines was inhibited by argentatin B. Forty-three percent HCT-15, and 66% PC-3 cells showed positive SA-β-galactosidase staining. The expression of PCNA was decreased, p21 expression was increased in both cell lines, but p27 expression increased only in PC-3 cells after treatment. Administration of argentatin B to healthy mice did not produce treatment-associated pathologies. However, it restricted the growth of HCT-15 and PC-3 tumors. These results indicate that treatment with argentatin B induces cell senescence.

  1. Immuno senescence: implications for cancer immunotherapy in elderly patients

    International Nuclear Information System (INIS)

    The aging process produces functional and developmental changes in the immune system. Those changes may occur at different levels or at different moments, from lymphopoiesis up to the final response of the immune system facing a certain disease. The response of the adaptive immune system is most strongly affected by the aging process, particularly at the level of the effector T-cells. These changes can have a negative impact on the immune response of elderly patients during cancer immunotherapy. The present paper is an updated review of the bibliography on the most important modifications produced in the immune system during aging, as well as on the relevance of these modifications for the design of new strategies for cancer immunotherapy. (Author)

  2. Cellular senescence in aging primates.

    Science.gov (United States)

    Herbig, Utz; Ferreira, Mark; Condel, Laura; Carey, Dee; Sedivy, John M

    2006-03-01

    The aging of organisms is characterized by a gradual functional decline of all organ systems. Mammalian somatic cells in culture display a limited proliferative life span, at the end of which they undergo an irreversible cell cycle arrest known as replicative senescence. Whether cellular senescence contributes to organismal aging has been controversial. We investigated telomere dysfunction, a recently discovered biomarker of cellular senescence, and found that the number of senescent fibroblasts increases exponentially in the skin of aging baboons, reaching >15% of all cells in very old individuals. In addition, the same cells contain activated ataxia-telangiectasia mutated kinase and heterochromatinized nuclei, confirming their senescent status. PMID:16456035

  3. Radiation promotes colorectal cancer initiation and progression by inducing senescence-associated inflammatory responses.

    Science.gov (United States)

    Kim, S B; Bozeman, R G; Kaisani, A; Kim, W; Zhang, L; Richardson, J A; Wright, W E; Shay, J W

    2016-06-30

    Proton radiotherapy is becoming more common as protons induce more precise DNA damage at the tumor site with reduced side effects to adjacent normal tissues. However, the long-term biological effects of proton irradiation in cancer initiation compared with conventional photon irradiation are poorly characterized. In this study, using a human familial adenomatous polyposis syndrome susceptible mouse model, we show that whole-body irradiation with protons are more effective in inducing senescence-associated inflammatory responses (SIRs), which are involved in colon cancer initiation and progression. After proton irradiation, a subset of SIR genes (Troy, Sox17, Opg, Faim2, Lpo, Tlr2 and Ptges) and a gene known to be involved in invasiveness (Plat), along with the senescence-associated gene (P19Arf), are markedly increased. Following these changes, loss of Casein kinase Iα and induction of chronic DNA damage and TP53 mutations are increased compared with X-ray irradiation. Proton irradiation also increases the number of colonic polyps, carcinomas and invasive adenocarcinomas. Pretreatment with the non-steroidal anti-inflammatory drug, 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid-ethyl amide (CDDO-EA), reduces proton irradiation-associated SIR and tumorigenesis. Thus exposure to proton irradiation elicits significant changes in colorectal cancer initiation and progression that can be mitigated using CDDO-EA. PMID:26477319

  4. Normal human mammary epithelial cells spontaneously escape senescence and acquire genomic changes

    Science.gov (United States)

    Romanov, S. R.; Kozakiewicz, B. K.; Holst, C. R.; Stampfer, M. R.; Haupt, L. M.; Tlsty, T. D.

    2001-01-01

    Senescence and genomic integrity are thought to be important barriers in the development of malignant lesions. Human fibroblasts undergo a limited number of cell divisions before entering an irreversible arrest, called senescence. Here we show that human mammary epithelial cells (HMECs) do not conform to this paradigm of senescence. In contrast to fibroblasts, HMECs exhibit an initial growth phase that is followed by a transient growth plateau (termed selection or M0; refs 3-5), from which proliferative cells emerge to undergo further population doublings (approximately 20-70), before entering a second growth plateau (previously termed senescence or M1; refs 4-6). We find that the first growth plateau exhibits characteristics of senescence but is not an insurmountable barrier to further growth. HMECs emerge from senescence, exhibit eroding telomeric sequences and ultimately enter telomere-based crisis to generate the types of chromosomal abnormalities seen in the earliest lesions of breast cancer. Growth past senescent barriers may be a pivotal event in the earliest steps of carcinogenesis, providing many genetic changes that predicate oncogenic evolution. The differences between epithelial cells and fibroblasts provide new insights into the mechanistic basis of neoplastic transformation.

  5. Multiple effects of electroporation on the adhesive behaviour of breast cancer cells and fibroblasts

    OpenAIRE

    Pehlivanova Viktoria N; Tsoneva Iana H; Tzoneva Rumiana D

    2012-01-01

    Abstract Background Recently electroporation using biphasic pulses was successfully applied in clinical developments for treating tumours in humans and animals. We evaluated the effects of electrical treatment on cell adhesion behaviour of breast cancer cells and fibroblasts. By applying bipolar electrical pulses we studied short- and long-lived effects on cell adhesion and survival, actin cytoskeleton and cell adhesion contacts in adherent cancer cells and fibroblasts. Methods Two cancer cel...

  6. The role of STAT1 for crosstalk between fibroblasts and colon cancer cells

    Directory of Open Access Journals (Sweden)

    Pawan eKaler

    2014-04-01

    Full Text Available Signaling between tumor cells and the associated stroma has an important impact on cancer initiation and progression. The tumor microenvironment has a paradoxical role in tumor progression and fibroblasts, a major component of the tumor stroma, have been shown to either inhibit or promote cancer development. In this study we established that normal intestinal fibroblasts activate STAT1 signaling in colon cancer cells and, in contrast to cancer- associated fibroblasts, inhibit growth of tumor cells. Treatment of 18Co fibroblasts with the proinflammatory cytokine TNF interfered with their ability to trigger STAT1 signaling in cancer cells. Accordingly, intestinal myofibroblasts isolated from patients with Ulcerative colitis (UC or Crohn’s disease (CD, which are activated and produce high levels of TNF, failed to stimulate STAT1 signaling in tumor cells, demonstrating that activated myofibroblasts lose the ability to trigger growth-inhibitory STAT1 signaling in tumor cells. Finally, we confirmed that silencing of STAT1 in tumor cells alters the crosstalk between tumor cells and fibroblasts, suggesting STAT1 as a novel link between intestinal inflammation and colon cancer. We demonstrated that normal fibroblasts restrain the growth of carcinoma cells, at least in part, through the induction of STAT1 signaling in cancer cells. We showed that changes in the microenvironment, as they occur in inflammatory bowel disease, alter the crosstalk between carcinoma cells and fibroblasts, perturb the homeostasis of intestinal tissue and thereby contribute to tumor progression.

  7. Exploring cell apoptosis and senescence to understand and treat cancer: an interview with Scott Lowe

    Directory of Open Access Journals (Sweden)

    2015-11-01

    Full Text Available Scott W. Lowe is currently principal investigator at the Memorial Sloan-Kettering Cancer Center. After beginning his studies in chemical engineering, he decided to take another path and became fascinated by biochemistry, genetics and molecular biology, which ultimately led to an interest in human disease, particularly cancer. During his PhD at the Massachusetts Institute of Technology (MIT, Scott had the opportunity to benefit from the exceptional mentorship of Earl Ruley, David Housman and Tyler Jacks, and contributed to elucidating how the p53 (TP53 tumor suppressor gene limits oncogenic transformation and modulates the cytotoxic response to conventional chemotherapy. This important work earned him a fellowship from the Cold Spring Harbor Laboratory, which helped to launch his independent career. Scott is now a leading scientist in the cancer field and his work has helped to shed light on mechanisms of cell apoptosis and senescence to better understand and treat cancer. In this interview, he talks about this incredible scientific journey.

  8. Suppression of the senescence-associated secretory phenotype (SASP) in human fibroblasts using small molecule inhibitors of p38 MAP kinase and MK2

    OpenAIRE

    Alimbetov, D; Davis, T.; Brook, AJC; Cox, LS; Faragher, RGA; Nurgozhin, T.; Zhumadilov, Z.; Kipling, D

    2015-01-01

    Senescent cells show an altered secretome profile termed the senescence-associated secretory phenotype (SASP). There is an increasing body of evidence that suggests that the accumulation of SASP-positive senescent cells in humans is partially causal in the observed shift to a low-level pro-inflammatory state in aged individuals. This in turn suggests the SASP as a possible therapeutic target to ameliorate inflammatory conditions in the elderly, and thus a better understanding of the signallin...

  9. Suppression of RAD21 Induces Senescence of MDA-MB-231 Human Breast Cancer Cells Through RB1 Pathway Activation Via c-Myc Downregulation.

    Science.gov (United States)

    Zhu, Shan; Zhao, Li; Li, Yueyang; Hou, Pingfu; Yao, Ruosi; Tan, Jiang; Liu, Dongxu; Han, Liping; Huang, Baiqu; Lu, Jun; Zhang, Yu

    2016-06-01

    Cellular senescence impedes cancer progression by limiting uncontrolled cell proliferation. To identify new genetic events controlling senescence, we performed a small interfering RNA screening human cancer cells and identified a number of targets potentially involved in senescence of MDA-MB-231 human breast cancer cells. Importantly, we showed that knockdown of RAD21 resulted in the appearance of several senescent markers, including enhanced senescence-associated β-galactosidase activity and heterochromatin focus formation, as well as elevated p21 protein levels and RB1 pathway activation. Further biochemical analyses revealed that RAD21 knockdown led to the downregulation of c-Myc and its targets, including CDK4, a negative regulator of RB1, and blockedRB1 phosphorylation (pRB1), and the RB1-mediated transcriptional repression of E2F. Moreover, c-Myc downregulation was partially mediated by proteasome-dependent degradation within promyelocytic leukemia (PML) nuclear bodies, which were found to be highly abundant during RAD21 knockdown-induced senescence. Exogenous c-Myc reconstitution rescued cells from RAD21 silencing-induced senescence. Altogether, data arising from this study implicate a novel function of RAD21 in cellular senescence in MDA-MB-231 cells that is mainly dependent onRB1 pathway activation via c-Myc downregulation. J. Cell. Biochem. 117: 1359-1369, 2016. © 2015 Wiley Periodicals, Inc. PMID:26529363

  10. p53 is required for metformin-induced growth inhibition, senescence and apoptosis in breast cancer cells.

    Science.gov (United States)

    Li, Puyu; Zhao, Ming; Parris, Amanda B; Feng, Xiaoshan; Yang, Xiaohe

    2015-09-01

    The p53 tumor repressor gene is commonly mutated in human cancers. The tumor inhibitory effect of metformin on p53-mutated breast cancer cells remains unclear. Data from the present study demonstrated that p53 knockdown or mutation has a negative effect on metformin or phenformin-induced growth inhibition, senescence and apoptosis in breast cancer cells. We also found that p53 reactivating agent nutlin-3α and CP/31398 promoted metformin-induced growth inhibition, senescence and apoptosis in MCF-7 (wt p53) and MDA-MB-231 (mt p53) cells, respectively. Treatment of MCF-7 cells with metformin or phenformin induced increase in p53 protein levels and the transcription of its downstream target genes, Bax and p21, in a dose-dependent manner. Moreover, we demonstrated that AMPK-mTOR signaling played a role in metformin-induced p53 up-regulation. The present study showed that p53 is required for metformin or phenformin-induced growth inhibition, senescence and apoptosis in breast cancer cells. The combination of metformin with p53 reactivating agents, like nutlin-3α and CP/31398, is a promising strategy for improving metformin-mediated anti-cancer therapy, especially for tumors with p53 mutations. PMID:26225749

  11. A Nampt inhibitor FK866 mimics vitamin B3 deficiency by causing senescence of human fibroblastic Hs68 cells via attenuation of NAD(+)-SIRT1 signaling.

    Science.gov (United States)

    Song, Tuzz-Ying; Yeh, Shu-Lan; Hu, Miao-Lin; Chen, Mei-Yau; Yang, Nae-Cherng

    2015-12-01

    Vitamin B3 (niacin) deficiency can cause pellagra with symptoms of dermatitis, diarrhea and dementia. However, it is unclear whether the vitamin B3 deficiency causes human aging. FK866 (a Nampt inhibitor) can reduce intracellular NAD(+) level and induce senescence of human Hs68 cells. However, the mechanisms underlying FK866-induced senescence of Hs68 cells are unclear. In this study, we used FK866 to mimic the effects of vitamin B3 deficiency to reduce the NAD(+) level and investigated the mechanisms of FK866-induced senescence of Hs68 cells. We hypothesized that FK866 induced the senescence of Hs68 cells via an attenuation of NAD(+)-silent information regulator T1 (SIRT1) signaling. We found that FK866 induced cell senescence and diminished cellular NAD(+) levels and SIRT1 activity (detected by acetylation of p53), and these effects were dramatically antagonized by co-treatment with nicotinic acid, nicotinamide, or NAD(+). In contrast, the protein expression of SIRT1, AMP-activated protein kinase, mammalian target of rapamycin, and nicotinamide phosphoribosyltransferase (Nampt) was not affected by FK866. In addition, the role of GSH in the FK866-induced cells senescence may be limited, as N-acetylcysteine did not antagonize FK866-induced cell senescence. These results suggest that FK866 induces cell senescence via attenuation of NAD(+)-SIRT1 signaling. The effects of vitamin B3 deficiency on human aging warrant further investigation. PMID:26330291

  12. Ultraconserved region-containing Transformer 2β4 controls senescence of colon cancer cells.

    Science.gov (United States)

    Kajita, K; Kuwano, Y; Satake, Y; Kano, S; Kurokawa, K; Akaike, Y; Masuda, K; Nishida, K; Rokutan, K

    2016-01-01

    Ultraconserved regions (UCRs) are >200 bp genomic segments with perfect human-to-rodent sequence identity. Transcribed UCRs constitute a new category of noncoding RNAs whose functions remain poorly understood. The human transformer 2β (TRA2B) gene contains a 419-bp UCR spanning the 276-bp exon 2 and its neighboring introns. TRA2B exon 2 has premature stop codons, whereas an exon 2-containing splice variant (TRA2β4) was expressed preferentially in the nuclei of human colon cancer cells. TRA2β4 knockdown p53-independently stimulated CDKN1A transcription and increased p21, resulting in the appearance of senescent cells. Biotin pull-down and RNA immunoprecipitation assays revealed that TRA2β4 interacted with Sp1 through a Sp1-binding sequence (485-GGGG-488) in a stem-loop structure of exon 2. Mutation of this sequence (485-AAGG-488) disrupted the stem-loop structure, blocked the interaction with Sp1 and increased CDKN1A transcription. Overexpression of TRA2β4 significantly decreased CDKN1A mRNA levels and accelerated cell growth, but the introduction of the mutation in the Sp1-binding sequence completely canceled these effects. Taken together, TRA2β4 may sequester Sp1 from occupying promoters of target genes including CDKN1A, promoting cell growth by interrupting the senescence-related gene expression program. This novel function of TRA2β4 may uncover an oncogenic function of transcribed UCRs. PMID:27043659

  13. Ultraconserved region-containing Transformer 2β4 controls senescence of colon cancer cells

    Science.gov (United States)

    Kajita, K; Kuwano, Y; Satake, Y; Kano, S; Kurokawa, K; Akaike, Y; Masuda, K; Nishida, K; Rokutan, K

    2016-01-01

    Ultraconserved regions (UCRs) are >200 bp genomic segments with perfect human-to-rodent sequence identity. Transcribed UCRs constitute a new category of noncoding RNAs whose functions remain poorly understood. The human transformer 2β (TRA2B) gene contains a 419-bp UCR spanning the 276-bp exon 2 and its neighboring introns. TRA2B exon 2 has premature stop codons, whereas an exon 2-containing splice variant (TRA2β4) was expressed preferentially in the nuclei of human colon cancer cells. TRA2β4 knockdown p53-independently stimulated CDKN1A transcription and increased p21, resulting in the appearance of senescent cells. Biotin pull-down and RNA immunoprecipitation assays revealed that TRA2β4 interacted with Sp1 through a Sp1-binding sequence (485-GGGG-488) in a stem-loop structure of exon 2. Mutation of this sequence (485-AAGG-488) disrupted the stem-loop structure, blocked the interaction with Sp1 and increased CDKN1A transcription. Overexpression of TRA2β4 significantly decreased CDKN1A mRNA levels and accelerated cell growth, but the introduction of the mutation in the Sp1-binding sequence completely canceled these effects. Taken together, TRA2β4 may sequester Sp1 from occupying promoters of target genes including CDKN1A, promoting cell growth by interrupting the senescence-related gene expression program. This novel function of TRA2β4 may uncover an oncogenic function of transcribed UCRs. PMID:27043659

  14. Oncogenes induce the cancer-associated fibroblast phenotype: Metabolic symbiosis and “fibroblast addiction” are new therapeutic targets for drug discovery

    OpenAIRE

    Lisanti, Michael P.; Martinez-Outschoorn, Ubaldo E; Sotgia, Federica

    2013-01-01

    Metabolic coupling, between mitochondria in cancer cells and catabolism in stromal fibroblasts, promotes tumor growth, recurrence, metastasis, and predicts anticancer drug resistance. Catabolic fibroblasts donate the necessary fuels (such as L-lactate, ketones, glutamine, other amino acids, and fatty acids) to anabolic cancer cells, to metabolize via their TCA cycle and oxidative phosphorylation (OXPHOS). This provides a simple mechanism by which metabolic energy and biomass are transferred f...

  15. Fibroblast recruitment as a tool for ovarian cancer detection and targeted therapy.

    Science.gov (United States)

    Oren, Roni; Addadi, Yoseph; Narunsky Haziza, Lian; Dafni, Hagit; Rotkopf, Ron; Meir, Gila; Fishman, Ami; Neeman, Michal

    2016-10-15

    Metastatic ovarian cancer, the most lethal of gynecologic malignancies, is typically managed by debulking surgery, followed by chemotherapy. However, despite significant efforts, survival rate remains low. We have previously demonstrated, in mouse models, a specific systemic homing of labeled fibroblasts to solid ovarian tumors. Here, we demonstrate the feasibility of utilizing this specific homing of genetically modified fibroblasts for detection and targeted therapy of orthotopic metastatic ovarian carcinoma model in immune-deficient mice. Using an in vivo metastatic mouse model for ovarian cancer, we demonstrated that fibroblasts expressing fluorescent reporters injected intra-peritoneally, were specifically recruited to peritoneal tumor nodules (resulting in 93-100% co-localization). We further used fibroblasts over expressing the soluble receptor variant of VEGFR1 (s-Flt1). Mice bearing tumors were injected weekly with either control or s-Flt1 expressing fibroblasts. Injection of s-Flt1 expressing fibroblasts resulted in a significant reduction in the ascites volume, reduced vascularization of adherent metastases, and improved overall survival. Using fluorescently labeled fibroblasts for tumor detection with readily available intra-operative fluorescence imaging tools may be useful for tumor staging and directing biopsies or surgical efforts during exploratory or debulking surgery. Fibroblasts may serve as a beacon pointing to the otherwise invisible metastases in the peritoneal cavity of ovarian cancer patients. Utilizing the recruited fibroblasts also for targeted delivery of anti angiogenic or antitumor molecules may aid in controlling tumor progression. Thus, these results suggest a novel approach for targeting ovarian tumor metastases for both tumor detection and therapy. PMID:27242346

  16. Gene expression signature of fibroblast serum response predicts human cancer progression: similarities between tumors and wounds.

    Directory of Open Access Journals (Sweden)

    Howard Y Chang

    2004-02-01

    Full Text Available Cancer invasion and metastasis have been likened to wound healing gone awry. Despite parallels in cellular behavior between cancer progression and wound healing, the molecular relationships between these two processes and their prognostic implications are unclear. In this study, based on gene expression profiles of fibroblasts from ten anatomic sites, we identify a stereotyped gene expression program in response to serum exposure that appears to reflect the multifaceted role of fibroblasts in wound healing. The genes comprising this fibroblast common serum response are coordinately regulated in many human tumors, allowing us to identify tumors with gene expression signatures suggestive of active wounds. Genes induced in the fibroblast serum-response program are expressed in tumors by the tumor cells themselves, by tumor-associated fibroblasts, or both. The molecular features that define this wound-like phenotype are evident at an early clinical stage, persist during treatment, and predict increased risk of metastasis and death in breast, lung, and gastric carcinomas. Thus, the transcriptional signature of the response of fibroblasts to serum provides a possible link between cancer progression and wound healing, as well as a powerful predictor of the clinical course in several common carcinomas.

  17. Oxidative stress triggered by naturally occurring flavone apigenin results in senescence and chemotherapeutic effect in human colorectal cancer cells

    Directory of Open Access Journals (Sweden)

    Kacoli Banerjee

    2015-08-01

    Full Text Available Recent studies involving phytochemical polyphenolic compounds have suggested flavones often exert pro-oxidative effect in vitro against wide array of cancer cell lines. The aim of this study was to evaluate the in-vitro pro-oxidative activity of apigenin, a plant based flavone against colorectal cancer cell lines and investigate cumulative effect on long term exposure. In the present study, treatment of colorectal cell lines HT-29 and HCT-15 with apigenin resulted in anti-proliferative and apoptotic effects characterized by biochemical and morphological changes, including loss of mitochondrial membrane potential which aided in reversing the impaired apoptotic machinery leading to negative implications in cancer pathogenesis. Apigenin induces rapid free radical species production and the level of oxidative damage was assessed by qualitative and quantitative estimation of biochemical markers of oxidative stress. Increased level of mitochondrial superoxide suggested dose dependent mitochondrial oxidative damage which was generated by disruption in anti-apoptotic and pro-apoptotic protein balance. Continuous and persistent oxidative stress induced by apigenin at growth suppressive doses over extended treatment time period was observed to induce senescence which is a natural cellular mechanism to attenuate tumor formation. Senescence phenotype inducted by apigenin was attributed to changes in key molecules involved in p16-Rb and p53 independent p21 signaling pathways. Phosphorylation of retinoblastoma was inhibited and significant up-regulation of p21 led to simultaneous suppression of cyclins D1 and E which indicated the onset of senescence. Pro-oxidative stress induced premature senescence mediated by apigenin makes this treatment regimen a potential chemopreventive strategy and an in vitro model for aging research.

  18. Shikonin Induces Apoptosis, Necrosis, and Premature Senescence of Human A549 Lung Cancer Cells through Upregulation of p53 Expression

    Directory of Open Access Journals (Sweden)

    Yueh-Chiao Yeh

    2015-01-01

    Full Text Available Shikonin, a natural naphthoquinone pigment isolated from Lithospermum erythrorhizon, has been reported to suppress growth of various cancer cells. This study was aimed to investigate whether this chemical could also inhibit cell growth of lung cancer cells and, if so, works via what molecular mechanism. To fulfill this, A549 lung cancer cells were treated with shikonin and then subjected to microscopic, biochemical, flow cytometric, and molecular analyses. Compared with the controls, shikonin significantly induced cell apoptosis and reduced proliferation in a dose-dependent manner. Specially, lower concentrations of shikonin (1–2.5 μg/mL cause viability reduction; apoptosis and cellular senescence induction is associated with upregulated expressions of cell cycle- and apoptotic signaling-regulatory proteins, while higher concentrations (5–10 μg/mL precipitate both apoptosis and necrosis. Treatment of cells with pifithrin-α, a specific inhibitor of p53, suppressed shikonin-induced apoptosis and premature senescence, suggesting the role of p53 in mediating the actions of shikonin on regulation of lung cancer cell proliferation. These results indicate the potential and dose-related cytotoxic actions of shikonin on A549 lung cancer cells via p53-mediated cell fate pathways and raise shikonin a promising adjuvant chemotherapeutic agent for treatment of lung cancer in clinical practice.

  19. RUNX1 and its fusion oncoprotein derivative RUNX1-ETO induce senescence-like growth arrest independently of replicative stress

    Science.gov (United States)

    Wolyniec, Kamil; Wotton, Sandy; Kilbey, Anna; Jenkins, Alma; Terry, Anne; Peters, Gordon; Stocking, Carol; Cameron, Ewan; Neil, James C.

    2016-01-01

    A role for the RUNX genes in cancer failsafe processes has been suggested by their induction of senescence-like growth arrest in primary murine fibroblasts and the failure of RAS-induced senescence in Runx2 deficient cells. We now show that RUNX1 induces senescence in human primary fibroblasts. High affinity DNA binding is necessary but not sufficient, as shown by the functional attenuation of the truncated RUNX1/AML1a isoform and the TEL-RUNX1 fusion oncoprotein. However, a similar phenotype was potently induced by the RUNX1-ETO (AML1-ETO) oncoprotein, despite its dominant negative potential. Detailed comparison of H-RASV12, RUNX1 and RUNX1-ETO senescent phenotypes showed that the RUNX effectors induce earlier growth stasis with only low levels of DNA damage signalling and a lack of chromatin condensation, a marker of irreversible growth arrest. In human fibroblasts, all effectors induced p53 in the absence of detectable p14ARF, while only RUNX1-ETO induced senescence in p16INK4a null cells. Correlation was noted between induction of p53, reactive oxygen species and phospho-p38, while p38MAPK inhibition rescued cell growth markedly. These findings reveal a role for replication-independent pathways in RUNX and RUNX1-ETO senescence, and show that the context-specific oncogenic activity of RUNX1 fusion proteins are mirrored in their distinctive interactions with failsafe responses. PMID:19448675

  20. Dasatinib reverses Cancer-associated Fibroblasts (CAFs from primary Lung Carcinomas to a Phenotype comparable to that of normal Fibroblasts

    Directory of Open Access Journals (Sweden)

    van der Kuip Heiko

    2010-06-01

    Full Text Available Abstract Cancer associated fibroblasts (CAFs play a critical role for growth, invasion, and metastasis of cancer. Therefore, targeting CAFs with small molecule inhibitors may be an attractive anti-tumor strategy. The current study aims to identify small molecule kinase inhibitors affecting CAF's growth and to characterize the biological effects of active compounds on primary CAFs from lung cancer. We screened two individual CAF strains for their sensitivity to a panel of 160 kinase inhibitors. Five kinase inhibitors were identified inhibiting more than 50% of the growth of both cell lines. Three of them were inhibitors of PDGFR at nanomolar concentrations. Therefore, we further tested the FDA approved PDGFR inhibitors Dasatinib, Nilotinib, Sorafenib, and Imatinib. All 37 CAF strains investigated were highly sensitive to Dasatinib at clinically relevant concentrations. Imatinib was slightly less effective, whereas the inhibitory effects of Nilotinib and Sorafenib were significantly less pronounced. We investigated the effect of Dasatinib on the CAF transcriptome by microarray analysis of 9 individual CAF strains. 492 genes were identified whose expression was changed at least twofold. 104 of these encoded cell cycle related proteins with 97 of them being downregulated by Dasatinib. The majority of regulated genes, however, were of diverse biological functions not directly related to proliferation. We compared this Dasatinib expression signature to previously described differential signatures of normal tissue associated fibroblasts (NAFs and CAFs and to a signature of fibroblast serum response. There was a significant overlap between genes regulated by Dasatinib and serum repression genes. More importantly, of the 313 genes downregulated by Dasatinib 64 were also reduced in NAFs compared to CAFs. Furthermore, 26 of 179 genes identified as upregulated by Dasatinib were also found to be elevated in NAFs compared to CAFs. These data demonstrate that

  1. Cancer-associated fibroblasts from human NSCLC survive ablative doses of radiation but their invasive capacity is reduced

    International Nuclear Information System (INIS)

    Cancer-Associated Fibroblasts (CAFs) are significant components of solid malignancies and play central roles in cancer sustainability, invasion and metastasis. In this study we have investigated the invasive capacity and matrix remodelling properties of human lung CAFs after exposure to ablative doses of ionizing radiation (AIR), equivalent to single fractions delivered by stereotactic ablative radiotherapy (SART) for medically inoperable stage-I/II non-small-cell lung cancers. CAFs were isolated from lung tumour specimens from 16 donors. Initially, intrinsic radiosensitivity was evaluated by checking viability and extent of DNA-damage response (DDR) at different radiation doses. The migrative and invasive capacities of CAFs were thereafter determined after a sub-lethal single radiation dose of 18 Gy. To ascertain the mechanisms behind the altered invasive capacity of cells, expression of matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) were measured in the conditioned media several days post-irradiation, along with expression of cell surface integrins and dynamics of focal contacts by vinculin-staining. Exposing CAFs to 1 × 18 Gy resulted in a potent induction of multiple nuclear DDR foci (> 9/cell) with little resolution after 120 h, induced premature cellular senescence and inhibition of the proliferative, migrative and invasive capacity. AIR promoted MMP-3 and inhibited MMP-1 appearance to some extent, but did not affect expression of other major MMPs. Furthermore, surface expression of integrins α2, β1 and α5 was consistently enhanced, and a dramatic augmentation and redistribution of focal contacts was observed. Our data indicate that ablative doses of radiation exert advantageous inhibitory effects on the proliferative, migratory and invasive capacity of lung CAFs. The reduced motility of irradiated CAFs might be a consequence of stabilized focal contacts via integrins

  2. Cancer-associated fibroblasts from human NSCLC survive ablative doses of radiation but their invasive capacity is reduced

    Directory of Open Access Journals (Sweden)

    Hellevik Turid

    2012-04-01

    Full Text Available Abstract Background Cancer-Associated Fibroblasts (CAFs are significant components of solid malignancies and play central roles in cancer sustainability, invasion and metastasis. In this study we have investigated the invasive capacity and matrix remodelling properties of human lung CAFs after exposure to ablative doses of ionizing radiation (AIR, equivalent to single fractions delivered by stereotactic ablative radiotherapy (SART for medically inoperable stage-I/II non-small-cell lung cancers. Methods CAFs were isolated from lung tumour specimens from 16 donors. Initially, intrinsic radiosensitivity was evaluated by checking viability and extent of DNA-damage response (DDR at different radiation doses. The migrative and invasive capacities of CAFs were thereafter determined after a sub-lethal single radiation dose of 18 Gy. To ascertain the mechanisms behind the altered invasive capacity of cells, expression of matrix metalloproteinases (MMPs and their endogenous inhibitors (TIMPs were measured in the conditioned media several days post-irradiation, along with expression of cell surface integrins and dynamics of focal contacts by vinculin-staining. Results Exposing CAFs to 1 × 18 Gy resulted in a potent induction of multiple nuclear DDR foci (> 9/cell with little resolution after 120 h, induced premature cellular senescence and inhibition of the proliferative, migrative and invasive capacity. AIR promoted MMP-3 and inhibited MMP-1 appearance to some extent, but did not affect expression of other major MMPs. Furthermore, surface expression of integrins α2, β1 and α5 was consistently enhanced, and a dramatic augmentation and redistribution of focal contacts was observed. Conclusions Our data indicate that ablative doses of radiation exert advantageous inhibitory effects on the proliferative, migratory and invasive capacity of lung CAFs. The reduced motility of irradiated CAFs might be a consequence of stabilized focal contacts via integrins.

  3. Senescence-Associated Secretory Phenotypes Reveal Cell-Nonautonomous Functions of Oncogenic RAS and the p53 Tumor Suppressor

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    Copp& #233; , Jean-Philippe; Patil, Christopher; Rodier, Francis; Sun, Yu; Munoz, Denise; Goldstein, Joshua; Nelson, Peter; Desprez, Pierre-Yves; Campisi, Judith

    2008-10-24

    Cellular senescence suppresses cancer by arresting cell proliferation, essentially permanently, in response to oncogenic stimuli, including genotoxic stress. We modified the use of antibody arrays to provide a quantitative assessment of factors secreted by senescent cells. We show that human cells induced to senesce by genotoxic stress secrete myriad factors associated with inflammation and malignancy. This senescence-associated secretory phenotype (SASP) developed slowly over several days and only after DNA damage of sufficient magnitude to induce senescence. Remarkably similar SASPs developed in normal fibroblasts, normal epithelial cells, and epithelial tumor cells after genotoxic stress in culture, and in epithelial tumor cells in vivo after treatment of prostate cancer patients with DNA-damaging chemotherapy. In cultured premalignant epithelial cells, SASPs induced an epithelial-mesenchyme transition and invasiveness, hallmarks of malignancy, by a paracrine mechanism that depended largely on the SASP factors interleukin (IL)-6 and IL-8. Strikingly, two manipulations markedly amplified, and accelerated development of, the SASPs: oncogenic RAS expression, which causes genotoxic stress and senescence in normal cells, and functional loss of the p53 tumor suppressor protein. Both loss of p53 and gain of oncogenic RAS also exacerbated the promalignant paracrine activities of the SASPs. Our findings define a central feature of genotoxic stress-induced senescence. Moreover, they suggest a cell-nonautonomous mechanism by which p53 can restrain, and oncogenic RAS can promote, the development of age-related cancer by altering the tissue microenvironment.

  4. Dexamethasone reduces sensitivity to cisplatin by blunting p53-dependent cellular senescence in non-small cell lung cancer.

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    Haiyan Ge

    Full Text Available INTRODUCTION: Dexamethasone (DEX co-treatment has proved beneficial in NSCLC patients, improving clinical symptoms by the reduction of side effects after chemotherapy. However, recent studies have shown that DEX could render cancer cells more insensitive to cytotoxic drug therapy, but it is not known whether DEX co-treatment could influence therapy-induced senescence (TIS, and unknown whether it is in a p53-dependent or p53-independent manner. METHODS: We examined in different human NSCLC cell lines and detected cellular senescence after cisplatin (DDP treatment in the presence or absence of DEX. The in vivo effect of the combination of DEX and DDP was assessed by tumor growth experiments using human lung cancer cell lines growing as xenograft tumors in nude mice. RESULTS: Co-treatment with DEX during chemotherapy in NSCLC resulted in increased tumor cell viability and inhibition of TIS compared with DDP treated group. DEX co-treatment cells exhibited the decrease of DNA damage signaling pathway proteins, the lower expression of p53 and p21(CIP1, the lower cellular secretory program and down-regulation of NF-κB and its signaling cascade. DEX also significantly reduced DDP sensitivity in vivo. CONCLUSIONS: Our results underscore that DEX reduces chemotherapy sensitivity by blunting therapy induced cellular senescence after chemotherapy in NSCLC, which may, at least in part, in a p53-dependent manner. These data therefore raise concerns about the widespread combined use of gluocorticoids (GCs with antineoplastic drugs in the clinical management of cancer patients.

  5. Effect of primarily cultured human lung cancer-associated fibroblasts on radiosensitivity of lung cancer cells

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of human lung cancer-associated fibroblasts (CAF) on the radiosensitivity of lung cancer cells when CAF is placed in direct contact co-culture with lung cancer cells. Methods: Human lung CAF was obtained from fresh human lung adenocarcinoma tissue specimens by primary culture and subculture and was then identified by immunofluorescence staining. The CAF was placed in direct contact co-culture with lung cancer A549 and H1299 cells, and the effects of CAF on the radiosensitivity of A549 and H1299 cells were evaluated by colony-forming assay. Results: The human lung CAF obtained by adherent culture could stably grow and proliferate, and it had specific expression of α-smooth muscle actin, vimentin, and fibroblast activation protein,but without expression of cytokeratin-18. The plating efficiency (PE, %) of A549 cells at 0 Gy irradiation was (20.0 ± 3.9)% when cultured alone versus (32.3 ± 5.5)% when co-cultured with CAF (t=3.16, P<0.05), and the PE of H1299 cells at 0 Gy irradiation was (20.6 ± 3.1)% when cultured alone versus (35.2 ± 2.3)% when co-cultured with CAF (t=6.55, P<0.05). The cell survival rate at 2 Gy irradiation (SF2) of A549 cells was 0.727 ±0.061 when cultured alone versus 0.782 ± 0.089 when co-cultured with CAF (t=0.88, P>0.05), and the SF2 of H1299 cells was 0.692 ±0.065 when cultured alone versus 0.782 ± 0.037 when co-cultured with CAF (t=2.08, P>0.05). The protection enhancement ratios of human lung CAF for A549 cells and H1299 cells were 1.29 and 1.25, respectively. Conclusions: Human lung CAF reduces the radiosensitivity of lung cancer cells when placed in direct contact co-culture with them, and the radioprotective effect may be attributed to CAF promoting the proliferation of lung cancer cells. (authors)

  6. Caveolin-1 Expression Level in Cancer Associated Fibroblasts Predicts Outcome in Gastric Cancer

    Science.gov (United States)

    Gao, Jun; Fan, Lifang; Li, Zonghuan; Yang, Guifang; Chen, Honglei

    2013-01-01

    Aims Altered expression of epithelial or stromal caveolin-1 (Cav-1) is observed in various types of human cancers. However, the clinical significance of Cav-1 expression in gastric cancer (GC) remains largely unknown. The present study aims to explore the clinicopathological significance and prognostic value of both tumor cells and cancer associated fibroblasts (CAFs) Cav-1 in GC. Methods and Results Quantum dots immunofluorescence histochemistry was performed to examine the expression of Cav-1 in 20 cases of gastritis without intestinal metaplasia (IM), 20 cases of gastritis with IM and 286 cases of GC. Positive rates of epithelial Cav-1 in gastritis without IM, gastritis with IM and GC showed a decreasing trend (P = 0.012). Low expression of Cav-1 in CAFs but not in tumor cells was an independent predictor of poor prognosis in GC patients (P = 0.034 and 0.005 respectively in disease free survival and overall survival). Cav-1 level in tumor cells and CAFs showed no significant correlation with classic clinicopathological features. Conclusions Loss of epithelial Cav-1 may promote malignant progression and low CAFs Cav-1 level herald worse outcome of GC patient, suggesting CAFs Cav-1 may be a candidate therapeutic target and a useful prognostic marker of GC. PMID:23527097

  7. Advanced Research of Fibroblast Growth Factor Receptor 
in Non-small Cell Lung Cancer

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    Dan PU

    2013-11-01

    Full Text Available Lung cancer is severely threatening human health. In recent years, the treatment for lung adenocarcinoma has made a great progress, targeted therapy has been widely applied in clinic, and benefits amount of patients. However, in squamous cell lung cancer, the incidence of epidermal growth factor receptor (EGFR gene mutant and ALK fusion gene are low,and targeted therapy like Tarceva and crizotinib, can hardly work. Since the fibroblast growth factors (fibroblast growth factor, FGF pathway is considered to be related to tumor cell proliferation, metastasis and angiogenesis, more and more researches proved the amplification of fibroblast growth factor receptor (FGFR in squamous cell lung cancer. Experiments in vivo and in vitro found that blocking FGF pathway could reduce the proliferation of tumor cells and inhibit metastasis. The FGF pathway might be a new target for treatment of squamous cell lung cancer. This article reviews the effect of FGFR in tumorigenesis,as well as the prospect as a therapeutic target in non-small cell lung cancer.

  8. Multiple effects of electroporation on the adhesive behaviour of breast cancer cells and fibroblasts

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    Pehlivanova Viktoria N

    2012-03-01

    Full Text Available Abstract Background Recently electroporation using biphasic pulses was successfully applied in clinical developments for treating tumours in humans and animals. We evaluated the effects of electrical treatment on cell adhesion behaviour of breast cancer cells and fibroblasts. By applying bipolar electrical pulses we studied short- and long-lived effects on cell adhesion and survival, actin cytoskeleton and cell adhesion contacts in adherent cancer cells and fibroblasts. Methods Two cancer cell lines (MDA-MB-231 and MCF-7 and one fibroblast cell line 3T3 were used. Cells were exposed to high field intensity (200 - 1000 V/cm. Cell adhesion and survival after electrical exposure were studied by crystal violet assay and MTS assay. Cytoskeleton rearrangement and cell adhesion contacts were visualized by actin staining and fluorescent microscope. Results The degree of electropermeabilization of the adherent cells elevated steadily with the increasing of the field intensity. Adhesion behaviour of fibroblasts and MCF-7 was not significantly affected by electrotreatment. Interestingly, treating the loosely adhesive cancer cell line MDA-MB-231 with 200 V/cm and 500 V/cm resulted in increased cell adhesion. Cell replication of both studied cancer cell lines was disturbed after electropermeabilization. Electroporation influenced the actin cytoskeleton in cancer cells and fibroblasts in different ways. Since it disturbed temporarily the actin cytoskeleton in 3T3 cells, in cancer cells treated with lower and middle field intensity actin cytoskeleton was well presented in stress fibers, filopodia and lamellipodia. The electrotreatment for cancer cells provoked preferentially cell-cell adhesion contacts for MCF-7 and cell-ECM contacts for MDA-MB- 231. Conclusions Cell adhesion and survival as well as the type of cell adhesion (cell-ECM or cell-cell adhesion induced by the electroporation process is cell specific. The application of suitable electric pulses can

  9. Clonogenic growth of human breast cancer cells co-cultured in direct contact with serum-activated fibroblasts

    International Nuclear Information System (INIS)

    Accumulating evidence suggests that fibroblasts play a pivotal role in promoting the growth of breast cancer cells. The objective of the present study was to characterize and validate an in vitro model of the interaction between small numbers of human breast cancer cells and human fibroblasts. We measured the clonogenic growth of small numbers of human breast cancer cells co-cultured in direct contact with serum-activated, normal human fibroblasts. Using DNA microarrays, we also characterized the gene expression profile of the serum-activated fibroblasts. In order to validate the in vivo relevance of our experiments, we then analyzed clinical samples of metastatic breast cancer for the presence of myofibroblasts expressing α-smooth muscle actin. Clonogenic growth of human breast cancer cells obtained directly from in situ and invasive tumors was dramatically and consistently enhanced when the tumor cells were co-cultured in direct contact with serum-activated fibroblasts. This effect was abolished when the cells were co-cultured in transwells separated by permeable inserts. The fibroblasts in our experimental model exhibited a gene expression signature characteristic of 'serum response' (i.e. myofibroblasts). Immunostaining of human samples of metastatic breast cancer tissue confirmed that myofibroblasts are in direct contact with breast cancer cells. Serum-activated fibroblasts promote the clonogenic growth of human breast cancer cells in vitro through a mechanism that involves direct physical contact between the cells. This model shares many important molecular and phenotypic similarities with the fibroblasts that are naturally found in breast cancers

  10. Pancreatitis-induced Inflammation Contributes to Pancreatic Cancer by Inhibiting Oncogene-Induced Senescence

    Science.gov (United States)

    Guerra, Carmen; Collado, Manuel; Navas, Carolina; Schuhmacher, Alberto J; Hernández-Porras, Isabel; Cañamero, Marta; Rodriguez-Justo, Manuel; Serrano, Manuel; Barbacid, Mariano

    2016-01-01

    Pancreatic acinar cells of adult mice (≥P60) are resistant to transformation by some of the most robust oncogenic insults including expression of K-Ras oncogenes and loss of p16Ink4a/p19Arf or Trp53 tumor suppressors. Yet, these acinar cells yield pancreatic intraepithelial neoplasias (mPanIN) and ductal adenocarcinomas (mPDAC) if exposed to limited bouts of non-acute pancreatitis, providing they harbor K-Ras oncogenes. Pancreatitis contributes to tumor progression by abrogating the senescence barrier characteristic of low-grade mPanINs. Attenuation of pancreatitis-induced inflammation also accelerates tissue repair and thwarts mPanIN expansion. Patients with chronic pancreatitis display senescent PanINs, if they have received anti-inflammatory drugs. These results put forward the concept that anti-inflammatory treatment of people diagnosed with pancreatitis may reduce their risk of developing PDAC. PMID:21665147

  11. Grow-ING, Age-ING and Die-ING: ING proteins link cancer, senescence and apoptosis

    International Nuclear Information System (INIS)

    The INhibitor of Growth (ING) family of plant homeodomain (PHD) proteins induce apoptosis and regulate gene expression through stress-inducible binding of phospholipids with subsequent nuclear and nucleolar localization. Relocalization occurs concomitantly with interaction with a subset of nuclear proteins, including PCNA, p53 and several regulators of acetylation such as the p300/CBP and PCAF histone acetyltransferases (HATs), as well as the histone deacetylases HDAC1 and hSir2. These interactions alter the localized state of chromatin compaction, subsequently affecting the expression of subsets of genes, including those associated with the stress response (Hsp70), apoptosis (Bax, MDM2) and cell cycle regulation (p21WAF1, cyclin B) in a cell- and tissue-specific manner. The expression levels and subcellular localization of ING proteins are altered in a significant number of human cancer types, while the expression of ING isoforms changes during cellular aging, suggesting that ING proteins may play a role in linking cellular transformation and replicative senescence. The variety of functions attributed to ING proteins suggest that this tumor suppressor serves to link the disparate processes of cell cycle regulation, cell suicide and cellular aging through epigenetic regulation of gene expression. This review examines recent findings in the ING field with a focus on the functions of protein-protein interactions involving ING family members and the mechanisms by which these interactions facilitate the various roles that ING proteins play in tumorigenesis, apoptosis and senescence

  12. Normal fibroblasts induce E-cadherin loss and increase lymph node metastasis in gastric cancer.

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    Wen Xu

    Full Text Available BACKGROUND: A tumor is considered a heterogeneous complex in a three-dimensional environment that is flush with pathophysiological and biomechanical signals. Cell-stroma interactions guide the development and generation of tumors. Here, we evaluate the contributions of normal fibroblasts to gastric cancer. METHODOLOGY/PRINCIPAL FINDINGS: By coculturing normal fibroblasts in monolayers of BGC-823 gastric cancer cells, tumor cells sporadically developed short, spindle-like morphological characteristics and demonstrated enhanced proliferation and invasive potential. Furthermore, the transformed tumor cells demonstrated decreased tumor formation and increased lymphomatic and intestinal metastatic potential. Non-transformed BGC-823 cells, in contrast, demonstrated primary tumor formation and delayed intestinal and lymph node invasion. We also observed E-cadherin loss and the upregulation of vimentin expression in the transformed tumor cells, which suggested that the increase in metastasis was induced by epithelial-to-mesenchymal transition. CONCLUSION: Collectively, our data indicated that normal fibroblasts sufficiently induce epithelial-to-mesenchymal transition in cancer cells, thereby leading to metastasis.

  13. Induction of Extracellular Matrix-Remodeling Genes by the Senescence-Associated Protein APA-1

    OpenAIRE

    Benanti, Jennifer A.; Williams, Dawnnica K.; Robinson, Kristin L; Ozer, Harvey L.; Galloway, Denise A.

    2002-01-01

    Human fibroblasts undergo cellular senescence after a finite number of divisions, in response to the erosion of telomeres. In addition to being terminally arrested in the cell cycle, senescent fibroblasts express genes that are normally induced upon wounding, including genes that remodel the extracellular matrix. We have identified the novel zinc finger protein APA-1, whose expression increased in senescent human fibroblasts independent of telomere shortening. Extended passage, telomerase-imm...

  14. Cancer associated fibroblasts promote tumor growth and metastasis by modulating the tumor immune microenvironment in a 4T1 murine breast cancer model.

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    Debbie Liao

    Full Text Available BACKGROUND: Local inflammation associated with solid tumors commonly results from factors released by tumor cells and the tumor stroma, and promotes tumor progression. Cancer associated fibroblasts comprise a majority of the cells found in tumor stroma and are appealing targets for cancer therapy. Here, our aim was to determine the efficacy of targeting cancer associated fibroblasts for the treatment of metastatic breast cancer. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that cancer associated fibroblasts are key modulators of immune polarization in the tumor microenvironment of a 4T1 murine model of metastatic breast cancer. Elimination of cancer associated fibroblasts in vivo by a DNA vaccine targeted to fibroblast activation protein results in a shift of the immune microenvironment from a Th2 to Th1 polarization. This shift is characterized by increased protein expression of IL-2 and IL-7, suppressed recruitment of tumor-associated macrophages, myeloid derived suppressor cells, T regulatory cells, and decreased tumor angiogenesis and lymphangiogenesis. Additionally, the vaccine improved anti-metastatic effects of doxorubicin chemotherapy and enhanced suppression of IL-6 and IL-4 protein expression while increasing recruitment of dendritic cells and CD8(+ T cells. Treatment with the combination therapy also reduced tumor-associated Vegf, Pdgfc, and GM-CSF mRNA and protein expression. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that cancer associated fibroblasts promote tumor growth and metastasis through their role as key modulators of immune polarization in the tumor microenvironment and are valid targets for therapy of metastatic breast cancer.

  15. Resveratrol Induced Premature Senescence Is Associated with DNA Damage Mediated SIRT1 and SIRT2 Down-Regulation.

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    Mehtap Kilic Eren

    Full Text Available The natural polyphenolic compound resveratrol (3,4,5-trihydroxy-trans-stilbene has broad spectrum health beneficial activities including antioxidant, anti-inflammatory, anti-aging, anti-cancer, cardioprotective, and neuroprotective effects. Remarkably, resveratrol also induces apoptosis and cellular senescence in primary and cancer cells. Resveratrol's anti-aging effects both in vitro and in vivo attributed to activation of a (NAD-dependent histone deacetylase family member sirtuin-1 (SIRT1 protein. In mammals seven members (SIRT1-7 of sirtuin family have been identified. Among those, SIRT1 is the most extensively studied with perceptive effects on mammalian physiology and suppression of the diseases of aging. Yet no data has specified the role of sirtuins, under conditions where resveratrol treatment induces senescence. Current study was undertaken to investigate the effects of resveratrol in human primary dermal fibroblasts (BJ and to clarify the role of sirtuin family members in particular SIRT1 and SIRT2 that are known to be involved in cellular stress responses and cell cycle, respectively. Here, we show that resveratrol decreases proliferation of BJ cells in a time and dose dependent manner. In addition the increase in senescence associated β-galactosidase (SA-β-gal activity and methylated H3K9-me indicate the induction of premature senescence. A significant increase in phosphorylation of γ-H2AX, a surrogate of DNA double strand breaks, as well as in levels of p53, p21CIP1 and p16INK4A is also detected. Interestingly, at concentrations where resveratrol induced premature senescence we show a significant decrease in SIRT1 and SIRT2 levels by Western Blot and quantitative RT-PCR analysis. Conversely inhibition of SIRT1 and SIRT2 via siRNA or sirtinol treatment also induced senescence in BJ fibroblasts associated with increased SA-β-gal activity, γ-H2AX phosphorylation and p53, p21CIP1 and p16INK4A levels. Interestingly DNA damaging

  16. The chalcone butein from Rhus verniciflua Stokes inhibits clonogenic growth of human breast cancer cells co-cultured with fibroblasts

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    Tan Jenny

    2005-03-01

    Full Text Available Abstract Background Butein (3,4,2',4'-tetrahydroxychalone, a plant polyphenol, is a major biologically active component of the stems of Rhus verniciflua Stokes. It has long been used as a food additive in Korea and as an herbal medicine throughout Asia. Recently, butein has been shown to suppress the functions of fibroblasts. Because fibroblasts are believed to play an important role in promoting the growth of breast cancer cells, we investigated the ability of butein to inhibit the clonogenic growth of small numbers of breast cancer cells co-cultured with fibroblasts in vitro. Methods We first measured the clonogenic growth of small numbers of the UACC-812 human breast cancer cell line co-cultured on monolayers of serum-activated, human fibroblasts in the presence of butein (2 μg/mL or various other modulators of fibroblast function (troglitazone-1 μg/mL; GW9662-1 μM; meloxican-1 μM; and 3,4 dehydroproline-10 μg/mL. In a subsequent experiment, we measured the dose-response effect on the clonogenic growth of UACC-812 breast cancer cells by pre-incubating the fibroblasts with varying concentrations of butein (10 μg/ml-1.25 μg/mL. Finally, we measured the clonogenic growth of primary breast cancer cells obtained from 5 clinical specimens with normal fibroblasts and with fibroblasts that had been pre-treated with a fixed dose of butein (2.5 μg/mL. Results Of the five modulators of fibroblast function that we tested, butein was by far the most potent inhibitor of clonogenic growth of UACC-812 breast cancer cells co-cultured with fibroblasts. Pre-treatment of fibroblasts with concentrations of butein as low as 2.5 μg/mL nearly abolished subsequent clonogenic growth of UACC-812 breast cancer cells co-cultured with the fibroblasts. A similar dose of butein had no effect on the clonogenic growth of breast cancer cells cultured in the absence of fibroblasts. Significantly, clonogenic growth of the primary breast cancer cells was also

  17. Low ERK phosphorylation in cancer-associated fibroblasts is associated with tamoxifen resistance in pre-menopausal breast cancer.

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    Susann Busch

    Full Text Available PURPOSE: The aim of this study was to evaluate ERK phosphorylation as a stromal biomarker for breast cancer prognosis and tamoxifen treatment prediction within a randomized tamoxifen trial. PATIENTS AND METHODS: Tissue microarrays of two breast cancer cohorts including in total 743 invasive breast cancer samples were analyzed for ERK phosphorylation (pERK and smooth muscle actin-alpha expression (SMAα in cancer-associated fibroblasts (CAFs and links to clinico-pathological data and treatment-predictive values were delineated. RESULTS: By analyzing a unique randomized tamoxifen trial including breast cancer patients receiving no adjuvant treatment we show for the first time that patients low in ERK phosphorylation in CAFs did not respond to tamoxifen treatment despite having estrogen-receptor alpha (ERα-positive tumors compared to patients with high pERK levels in CAFs (P = 0.015, multivariate Cox regression interaction analysis. In both clinical materials we further show a significant association between pERK and SMAα, a characteristic marker for activated fibroblasts. SMAα expression however was not linked to treatment-predictive information but instead had prognostic qualities. CONCLUSION: The data suggests that the presence of a subpopulation of CAFs, defined by minimal activated ERK signaling, is linked to an impaired tamoxifen response. Thus, this report illustrates the importance of the stroma for monitoring treatment effects in pre-menopausal breast cancer.

  18. Fibroblast growth factor receptor inhibitors as a cancer treatment: from a biologic rationale to medical perspectives.

    Science.gov (United States)

    Dieci, Maria Vittoria; Arnedos, Monica; Andre, Fabrice; Soria, Jean Charles

    2013-03-01

    The fibroblast growth factor/fibroblast growth factor receptor (FGF/FGFR) signaling pathway plays a fundamental role in many physiologic processes, including embryogenesis, adult tissue homeostasis, and wound healing, by orchestrating angiogenesis. Ligand-independent and ligand-dependent activation have been implicated in a broad range of human malignancies and promote cancer progression in tumors driven by FGF/FGFR oncogenic mutations or amplifications, tumor neoangiogenesis, and targeted treatment resistance, thereby supporting a strong rationale for anti-FGF/FGFR agent development. Efforts are being pursued to develop selective approaches for use against this pathway by optimizing the management of emerging, class-specific toxicity profiles and correctly designing clinical trials to address these different issues. PMID:23418312

  19. Cancer-associated fibroblasts as another polarized cell type of the tumor microenvironment

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    MartinAugsten

    2014-03-01

    Full Text Available Tumor- or cancer-associated fibroblasts (CAFs are one of the most abundant stromal cell types in different carcinomas and comprise a heterogeneous cell population. Classically, CAFs are assigned with pro-tumorigenic effects stimulating tumor growth and progression. More recent studies demonstrated also tumor-inhibitory effects of CAFs suggesting that tumor-residing fibroblasts exhibit a similar degree of plasticity as other stromal cell types. Reciprocal interactions with the tumor milieu and different sources of origin are emerging as two important factors underlying CAF heterogeneity. This review highlights recent advances in our understanding of CAF biology and proposes to expand the term of cellular ´polarization´, previously introduced to describe different activation states of various immune cells, onto CAFs to reflect their phenotypic diversity.

  20. Antiproliferative effects of phenylaminonaphthoquinones are increased by ascorbate and associated with the appearance of a senescent phenotype in human bladder cancer cells

    International Nuclear Information System (INIS)

    Highlights: •Phenylaminonaphthoquinones are redox cyclers able to form ROS. •Phenylaminonaphthoquinones plus ascorbate inhibit T24 cell growth. •Phenylaminonaphthoquinones plus ascorbate lead to necrotic-like cell death. •Phenylaminonaphthoquinones plus ascorbate impair cell cycle and affect MAPKs. •Phenylaminonaphthoquinones plus ascorbate induce a senescent cancer cell phenotype. -- Abstract: Quinone-containing molecules have been developed against cancer mainly for their redox cycling ability leading to reactive oxygen species (ROS) formation. We have previously shown that donor-acceptor phenylaminonaphthoquinones are biologically active against a panel of cancer cells. In this report, we explored the mechanisms involved in cancer cell growth inhibition caused by two phenylaminonaphthoquinones, namely Q7 and Q9, with or without ascorbate (ASC). The results show that Q7 and Q9 are both redox cyclers able to form ROS, which strongly inhibit the proliferation of T24 cells. Q9 was a better redox cycler than Q7 because of marked stabilization of the semiquinone radical species arising from its reduction by ascorbate. Indeed, ASC dramatically enhances the inhibitory effect of Q9 on cell proliferation. Q9 plus ASC impairs the cell cycle, causing a decrease in the number of cells in the G2/M phase without involving other cell cycle regulating key proteins. Moreover, Q9 plus ASC influences the MAPK signaling pathways, provoking the appearance of a senescent cancer cell phenotype and ultimately leading to necrotic-like cell death. Because cellular senescence limits the replicative capacity of cells, our results suggest that induction of senescence may be exploited as a basis for new approaches to cancer therapy

  1. Antiproliferative effects of phenylaminonaphthoquinones are increased by ascorbate and associated with the appearance of a senescent phenotype in human bladder cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Felipe, K.B. [Laboratorio de Bioquímica Experimental, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis (Brazil); Benites, J. [Facultad de Ciencias de la Salud, Universidad Arturo Prat, Avenida Arturo Prat 2120, Casilla 121, Iquique (Chile); Glorieux, C.; Sid, B.; Valenzuela, M. [Université Catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group (GTOX), Brussels (Belgium); Kviecinski, M.R.; Pedrosa, R.C. [Laboratorio de Bioquímica Experimental, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis (Brazil); Valderrama, J.A. [Departamento Química Orgánica, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Casilla 306, Santiago (Chile); Levêque, Ph.; Gallez, B. [Université Catholique de Louvain, Louvain Drug Research Institute, Biomedical Magnetic Resonance Research Group (REMA), Brussels (Belgium); Verrax, J. [Université Catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group (GTOX), Brussels (Belgium); Buc Calderon, P., E-mail: pedro.buccalderon@uclouvain.be [Facultad de Ciencias de la Salud, Universidad Arturo Prat, Avenida Arturo Prat 2120, Casilla 121, Iquique (Chile); Université Catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group (GTOX), Brussels (Belgium)

    2013-04-19

    Highlights: •Phenylaminonaphthoquinones are redox cyclers able to form ROS. •Phenylaminonaphthoquinones plus ascorbate inhibit T24 cell growth. •Phenylaminonaphthoquinones plus ascorbate lead to necrotic-like cell death. •Phenylaminonaphthoquinones plus ascorbate impair cell cycle and affect MAPKs. •Phenylaminonaphthoquinones plus ascorbate induce a senescent cancer cell phenotype. -- Abstract: Quinone-containing molecules have been developed against cancer mainly for their redox cycling ability leading to reactive oxygen species (ROS) formation. We have previously shown that donor-acceptor phenylaminonaphthoquinones are biologically active against a panel of cancer cells. In this report, we explored the mechanisms involved in cancer cell growth inhibition caused by two phenylaminonaphthoquinones, namely Q7 and Q9, with or without ascorbate (ASC). The results show that Q7 and Q9 are both redox cyclers able to form ROS, which strongly inhibit the proliferation of T24 cells. Q9 was a better redox cycler than Q7 because of marked stabilization of the semiquinone radical species arising from its reduction by ascorbate. Indeed, ASC dramatically enhances the inhibitory effect of Q9 on cell proliferation. Q9 plus ASC impairs the cell cycle, causing a decrease in the number of cells in the G2/M phase without involving other cell cycle regulating key proteins. Moreover, Q9 plus ASC influences the MAPK signaling pathways, provoking the appearance of a senescent cancer cell phenotype and ultimately leading to necrotic-like cell death. Because cellular senescence limits the replicative capacity of cells, our results suggest that induction of senescence may be exploited as a basis for new approaches to cancer therapy.

  2. Activated FXR Inhibits Leptin Signaling and Counteracts Tumor-promoting Activities of Cancer-Associated Fibroblasts in Breast Malignancy

    OpenAIRE

    Cinzia Giordano; Ines Barone; Valentina Vircillo; Salvatore Panza; Rocco Malivindi; Luca Gelsomino; Michele Pellegrino; Vittoria Rago; Loredana Mauro; Marilena Lanzino; Maria Luisa Panno; Daniela Bonofiglio; Stefania Catalano; Sebastiano Andò

    2016-01-01

    Cancer-associated fibroblasts (CAFs), the principal components of the tumor stroma, play a central role in cancer development and progression. As an important regulator of the crosstalk between breast cancer cells and CAFs, the cytokine leptin has been associated to breast carcinogenesis. The nuclear Farnesoid X Receptor-(FXR) seems to exert an oncosuppressive role in different tumors, including breast cancer. Herein, we demonstrated, for the first time, that the synthetic FXR agonist GW4064,...

  3. MUC4 potentiates invasion and metastasis of pancreatic cancer cells through stabilization of fibroblast growth factor receptor 1

    OpenAIRE

    Rachagani, Satyanarayana; Muzafar A Macha; Moorthy P Ponnusamy; Haridas, Dhanya; Kaur, Sukhwinder; Jain, Maneesh; Batra, Surinder K.

    2012-01-01

    MUC4 is a type-1 transmembrane mucin differentially expressed in multiple cancers and has previously been shown to potentiate progression and metastasis of pancreatic cancer. In this study, we investigated the molecular mechanisms associated with the MUC4-induced invasion and metastasis in pancreatic cancer. Stable silencing of MUC4 in multiple pancreatic cancer cells resulted in the downregulation of N-cadherin and its interacting partner fibroblast growth factor receptor 1 (FGFR1) through d...

  4. Androgen receptor drives cellular senescence.

    Directory of Open Access Journals (Sweden)

    Yelena Mirochnik

    Full Text Available The accepted androgen receptor (AR role is to promote proliferation and survival of prostate epithelium and thus prostate cancer progression. While growth-inhibitory, tumor-suppressive AR effects have also been documented, the underlying mechanisms are poorly understood. Here, we for the first time link AR anti-cancer action with cell senescence in vitro and in vivo. First, AR-driven senescence was p53-independent. Instead, AR induced p21, which subsequently reduced ΔN isoform of p63. Second, AR activation increased reactive oxygen species (ROS and thereby suppressed Rb phosphorylation. Both pathways were critical for senescence as was proven by p21 and Rb knock-down and by quenching ROS with N-Acetyl cysteine and p63 silencing also mimicked AR-induced senescence. The two pathways engaged in a cross-talk, likely via PML tumor suppressor, whose localization to senescence-associated chromatin foci was increased by AR activation. All these pathways contributed to growth arrest, which resolved in senescence due to concomitant lack of p53 and high mTOR activity. This is the first demonstration of senescence response caused by a nuclear hormone receptor.

  5. The thorny path linking cellular senescence to organismalaging

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Christopher K.; Mian, Saira; Campisi, Judith

    2005-08-09

    Half a century is fast approaching since Hayflick and colleagues formally described the limited ability of normal human cells to proliferate in culture (Hayflick and Moorhead, 1961). This finding--that normal somatic cells, in contrast to cancer cells, cannot divide indefinitely--challenged the prevailing idea that cells from mortal multicellular organisms were intrinsically ''immortal'' (Carrell, 1912). It also spawned two hypotheses, essential elements of which persist today. The first held that the restricted proliferation of normal cells, now termed cellular senescence, suppresses cancer (Hayflick, 1965; Sager, 1991; Campisi, 2001). The second hypothesis, as explained in the article by Lorenzini et al., suggested that the limited proliferation of cells in culture recapitulated aspects of organismal aging (Hayflick, 1965; Martin, 1993). How well have these hypotheses weathered the ensuing decades? Before answering this question, we first consider current insights into the causes and consequences of cellular senescence. Like Lorenzini et al., we limit our discussion to mammals. We also focus on fibroblasts, the cell type studied by Lorenzini et al., but consider other types as well. We suggest that replicative capacity in culture is not a straightforward assessment, and that it correlates poorly with both longevity and body mass. We speculate this is due to the malleable and variable nature of replicative capacity, which renders it an indirect metric of qualitative and quantitative differences among cells to undergo senescence, a response that directly alters cellular phenotype and might indirectly alter tissue structure and function.

  6. Covalent Targeting of Fibroblast Growth Factor Receptor Inhibits Metastatic Breast Cancer.

    Science.gov (United States)

    Brown, Wells S; Tan, Li; Smith, Andrew; Gray, Nathanael S; Wendt, Michael K

    2016-09-01

    Therapeutic targeting of late-stage breast cancer is limited by an inadequate understanding of how tumor cell signaling evolves during metastatic progression and by the currently available small molecule inhibitors capable of targeting these processes. Herein, we demonstrate that both β3 integrin and fibroblast growth factor receptor-1 (FGFR1) are part of an epithelial-mesenchymal transition (EMT) program that is required to facilitate metastatic outgrowth in response to fibroblast growth factor-2 (FGF2). Mechanistically, β3 integrin physically disrupts an interaction between FGFR1 and E-cadherin, leading to a dramatic redistribution of FGFR1 subcellular localization, enhanced FGF2 signaling and increased three-dimensional (3D) outgrowth of metastatic breast cancer cells. This ability of β3 integrin to drive FGFR signaling requires the enzymatic activity of focal adhesion kinase (FAK). Consistent with these mechanistic data, we demonstrate that FGFR, β3 integrin, and FAK constitute a molecular signature capable of predicting decreased survival of patients with the basal-like subtype of breast cancer. Importantly, covalent targeting of a conserved cysteine in the P-loop of FGFR1-4 with our newly developed small molecule, FIIN-4, more effectively blocks 3D metastatic outgrowth as compared with currently available FGFR inhibitors. In vivo application of FIIN-4 potently inhibited the growth of metastatic, patient-derived breast cancer xenografts and murine-derived metastases growing within the pulmonary microenvironment. Overall, the current studies demonstrate that FGFR1 works in concert with other EMT effector molecules to drive aberrant downstream signaling, and that these events can be effectively targeted using our novel therapeutics for the treatment of the most aggressive forms of breast cancer. Mol Cancer Ther; 15(9); 2096-106. ©2016 AACR. PMID:27371729

  7. Transformable Peptide Nanocarriers for Expeditious Drug Release and Effective Cancer Therapy via Cancer-Associated Fibroblast Activation.

    Science.gov (United States)

    Ji, Tianjiao; Zhao, Ying; Ding, Yanping; Wang, Jing; Zhao, Ruifang; Lang, Jiayan; Qin, Hao; Liu, Xiaoman; Shi, Jian; Tao, Ning; Qin, Zhihai; Nie, Guangjun; Zhao, Yuliang

    2016-01-18

    A novel cleavable amphiphilic peptide (CAP) was designed to be specifically responsive to fibroblast activation protein-α (FAP-α), a protease specifically expressed on the surface of cancer-associated fibroblasts. The CAP self-assembled into fiber-like nanostructures in solution, while the presence of hydrophobic chemotherapeutic drugs readily transformed the assemblies into drug-loaded spherical nanoparticles. The disassembly of these nanoparticles (CAP-NPs) upon FAP-α cleavage resulted in rapid and efficient release of the encapsulated drugs specifically at tumor sites. This Transformers-like drug delivery strategy could allow them to disrupt the stromal barrier and enhance local drug accumulation. Therapeutic results suggested that drug-loaded CAP-NPs hold promising tumor specificity and therapeutic efficacy for various solid tumor models, confirming its potential utility and versatility in antitumor therapy. PMID:26283097

  8. A role for p53 in selenium-induced senescence

    Science.gov (United States)

    The tumor suppressor p53 and the ataxia-telangiectasia mutated (ATM) kinase play important roles in the senescence response to oncogene activation and DNA damage. We have previously shown that selenium-containing compounds can activate an ATM-dependent senescence response in MRC-5 normal fibroblasts...

  9. Exosome-mediated delivery of miR-9 induces cancer-associated fibroblast-like properties in human breast fibroblasts.

    Science.gov (United States)

    Baroni, S; Romero-Cordoba, S; Plantamura, I; Dugo, M; D'Ippolito, E; Cataldo, A; Cosentino, G; Angeloni, V; Rossini, A; Daidone, M G; Iorio, M V

    2016-01-01

    It is established that the interaction between microenvironment and cancer cells has a critical role in tumor development, given the dependence of neoplastic cells on stromal support. However, how this communication promotes the activation of normal (NFs) into cancer-associated fibroblasts (CAFs) is still not well understood. Most microRNA (miRNA) studies focused on tumor cell, but there is increasing evidence of their involvement in reprogramming NFs into CAFs. Here we show that miR-9, upregulated in various breast cancer cell lines and identified as pro-metastatic miRNA, affects the properties of human breast fibroblasts, enhancing the switch to CAF phenotype, thus contributing to tumor growth. Expressed at higher levels in primary triple-negative breast CAFs versus NFs isolated from patients, miR-9 improves indeed migration and invasion capabilities when transfected in immortalized NFs; viceversa, these properties are strongly impaired in CAFs upon miR-9 inhibition. We also demonstrate that tumor-secreted miR-9 can be transferred via exosomes to recipient NFs and this uptake results in enhanced cell motility. Moreover, we observed that this miRNA is also secreted by fibroblasts and in turn able to alter tumor cell behavior, by modulating its direct target E-cadherin, and NFs themselves. Consistently with the biological effects observed, gene expression profiles of NFs upon transient transfection with miR-9 show the modulation of genes mainly involved in cell motility and extracellular matrix remodeling pathways. Finally, we were able to confirm the capability of NFs transiently transfected with miR-9 to promote in vivo tumor growth. Taken together, these data provide new insights into the role of miR-9 as an important player in the cross-talk between cancer cells and stroma. PMID:27468688

  10. Exosome-mediated delivery of miR-9 induces cancer-associated fibroblast-like properties in human breast fibroblasts

    Science.gov (United States)

    Baroni, S; Romero-Cordoba, S; Plantamura, I; Dugo, M; D'Ippolito, E; Cataldo, A; Cosentino, G; Angeloni, V; Rossini, A; Daidone, M G; Iorio, M V

    2016-01-01

    It is established that the interaction between microenvironment and cancer cells has a critical role in tumor development, given the dependence of neoplastic cells on stromal support. However, how this communication promotes the activation of normal (NFs) into cancer-associated fibroblasts (CAFs) is still not well understood. Most microRNA (miRNA) studies focused on tumor cell, but there is increasing evidence of their involvement in reprogramming NFs into CAFs. Here we show that miR-9, upregulated in various breast cancer cell lines and identified as pro-metastatic miRNA, affects the properties of human breast fibroblasts, enhancing the switch to CAF phenotype, thus contributing to tumor growth. Expressed at higher levels in primary triple-negative breast CAFs versus NFs isolated from patients, miR-9 improves indeed migration and invasion capabilities when transfected in immortalized NFs; viceversa, these properties are strongly impaired in CAFs upon miR-9 inhibition. We also demonstrate that tumor-secreted miR-9 can be transferred via exosomes to recipient NFs and this uptake results in enhanced cell motility. Moreover, we observed that this miRNA is also secreted by fibroblasts and in turn able to alter tumor cell behavior, by modulating its direct target E-cadherin, and NFs themselves. Consistently with the biological effects observed, gene expression profiles of NFs upon transient transfection with miR-9 show the modulation of genes mainly involved in cell motility and extracellular matrix remodeling pathways. Finally, we were able to confirm the capability of NFs transiently transfected with miR-9 to promote in vivo tumor growth. Taken together, these data provide new insights into the role of miR-9 as an important player in the cross-talk between cancer cells and stroma. PMID:27468688

  11. Senescent Remodeling of the Innate and Adaptive Immune System in the Elderly Men with Prostate Cancer

    OpenAIRE

    Gianluigi Taverna; Mauro Seveso; Guido Giusti; Rodolfo Hurle; Pierpaolo Graziotti; Sanja Štifter; Maurizio Chiriva-Internati; Fabio Grizzi

    2014-01-01

    Despite years of intensive investigation that has been made in understanding prostate cancer, it remains a major cause of death in men worldwide. Prostate cancer emerges from multiple alterations that induce changes in expression patterns of genes and proteins that function in networks controlling critical cellular events. Based on the exponential aging of the population and the increasing life expectancy in industrialized Western countries, prostate cancer in the elderly men is becoming a di...

  12. Tyrosine kinase signalling in breast cancer: Fibroblast growth factors and their receptors

    International Nuclear Information System (INIS)

    The fibroblast growth factors [Fgfs (murine), FGFs (human)] constitute a large family of ligands that signal through a class of cell-surface tyrosine kinase receptors. Fgf signalling has been associated in vitro with cellular differentiation as well as mitogenic and motogenic responses. In vivo, Fgfs are critical for animal development, and some have potent angiogenic properties. Several Fgfs have been identified as oncogenes in murine mammary cancer, where their deregulation is associated with proviral insertions of the mouse mammary tumour virus (MMTV). Thus, in some mammary tumours of MMTV-infected mouse strains, integration of viral genomic DNA into the somatic DNA of mammary epithelial cells was found to have caused the inappropriate expression of members of this family of growth factors. Although examination of human breast cancers has shown an altered expression of FGFs or of their receptors in some tumours, their role in the causation of breast disease is unclear and remains controversial

  13. Cellular senescence and tumor promotion: Is aging the key?

    Science.gov (United States)

    Loaiza, Natalia; Demaria, Marco

    2016-04-01

    The senescence response is a potent tumor suppressor mechanism characterized by an irreversible growth arrest in response to potentially oncogenic signals to prevent the proliferation of damaged cells. Late in life, some of the features of senescent cells seem to mediate the development of age-related pathologies, including cancer. In the present review, we present a summary of the current knowledge regarding the causes, effector pathways and cellular features of senescence. We also discuss how the senescence response, initially a tumor suppressor mechanism, turns into a tumor promoter apparently as a consequence of aging. We argue that three age-related phenomena-senescence-associated secretory phenotype (SASP) dysregulation, decline in the immune system function and genomic instability-could contribute, independently or synergistically, to deteriorate the efficacy of the senescence response in stopping cancer. As a consequence, senescent cells could be considered premalignant cells, and targeting senescent cells could be a preventive and therapeutic strategy against cancer. PMID:26845683

  14. Co-targeting Deoxyribonucleic Acid–Dependent Protein Kinase and Poly(Adenosine Diphosphate-Ribose) Polymerase-1 Promotes Accelerated Senescence of Irradiated Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Azad, Arun, E-mail: arun.azad@bccancer.bc.ca [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Pathology, St. Vincent' s Hospital, University of Melbourne, Parkville, Victoria (Australia); Bukczynska, Patricia; Jackson, Susan [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Haput, Ygal; Cullinane, Carleen [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia); McArthur, Grant A.; Solomon, Benjamin [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Division of Cancer Medicine, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Medicine, St. Vincent' s Hospital, University of Melbourne, Parkville, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia)

    2014-02-01

    Purpose: To examine the effects of combined blockade of DNA-dependent protein kinase (DNA-PK) and poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1) on accelerated senescence in irradiated H460 and A549 non-small cell lung cancer cells. Methods and Materials: The effects of KU5788 and AG014699 (inhibitors of DNA-PK and PARP-1, respectively) on clonogenic survival, DNA double-strand breaks (DSBs), apoptosis, mitotic catastrophe, and accelerated senescence in irradiated cells were examined in vitro. For in vivo experiments, H460 xenografts established in athymic nude mice were treated with BEZ235 (a DNA-PK, ATM, and phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor) and AG014699 to determine effects on proliferation, DNA DSBs, and accelerated senescence after radiation. Results: Compared with either inhibitor alone, combination treatment with KU57788 and AG014699 reduced postradiation clonogenic survival and significantly increased persistence of Gamma-H2AX (γH2AX) foci in irradiated H460 and A549 cells. Notably, these effects coincided with the induction of accelerated senescence in irradiated cells as reflected by positive β-galactosidase staining, G2-M cell-cycle arrest, enlarged and flattened cellular morphology, increased p21 expression, and senescence-associated cytokine secretion. In irradiated H460 xenografts, concurrent therapy with BEZ235 and AG014699 resulted in sustained Gamma-H2AX (γH2AX) staining and prominent β-galactosidase activity. Conclusion: Combined DNA-PK and PARP-1 blockade increased tumor cell radiosensitivity and enhanced the prosenescent properties of ionizing radiation in vitro and in vivo. These data provide a rationale for further preclinical and clinical testing of this therapeutic combination.

  15. Cancer-associated fibroblasts are not formed from cancer cells by epithelial-to-mesenchymal transition in nu/nu mice

    Czech Academy of Sciences Publication Activity Database

    Dvořánková, B.; Smetana Jr, K.; Říhová, Blanka; Kučera, J.; Mateu, R.; Szabo, P.

    2015-01-01

    Roč. 143, č. 5 (2015), s. 463-469. ISSN 0948-6143 R&D Projects: GA ČR(CZ) GAP301/12/1254; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : Cancer stroma * Cancer -associated fibroblast * Myofibroblast Subject RIV: EC - Immunology Impact factor: 2.927, year: 2013

  16. Low power laser effects in cancer cells and fibroblasts submitted the ionizing radiation; Efeitos do laser de baixa potencia em celulas de linhagem tumoral e fibroblastos submetidos a radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Camila Ramos

    2015-07-01

    Cancer is considered a public health problem worldwide. According to Brazil's the National Cancer Institute (INCA), 576,000 new cases of cancer were estimated for 2015 in Brazil, representing the second leading cause of death. Radiotherapy may be a treatment to several of types of cancer, frequently using ionizing radiation to eradicate or prevent the proliferation of tumor cells. This treatment, however, can lead to death of non-tumor cells around in irradiated tissue. Given this, adjuvant therapies that can minimize the side effects of ionizing radiation are of extremely importance. In this context, low power laser (LPL) may be an alternative to modulate the response of healthy cells to ionizing radiation. In this study, cells of human gingival fibroblasts (FMM1) and breast cancer (MDAMB- 231) were exposed to gamma radiation at doses of 2.5 and 10 Gy. After twenty-four hours, cell were irradiated with LPL ( λ= 660 nm, 40 mW and total area of 0.04 cm²) with energy densities of 30, 60, 90, 120 and 150 J/cm². The cell viability was measured during four days, using the trypan blue technique. The influence of LPL on the cell cycle and on expression of the nuclear antigen of cellular proliferation (PCNA) was evaluated by flow cytometry. The expression of β-Galactosidase was the chosen method to assess cell senescence. Considering our adopted parameters, and focusing on the non-tumor cells, we have observed an increase in: 1) cell viability; 2) cell population in phases S and G{sub 2}/M cell cycle; 3) PCNA expression with decrease in senescence. No alterations were observed in the cell viability, with greater population in phases S and G{sub 2}/M cell cycle, while the number of senescent cells and the expression of PCNA were decreased. Therefore, we have concluded that the LPL promoted effects on both cell lineages, with increased cell viability on FMM1 cells, whether cancer cells maintained a decreased proliferation. (author)

  17. Aberrant DNA methylation in non-small cell lung cancer-associated fibroblasts

    Science.gov (United States)

    Vizoso, Miguel; Puig, Marta; Carmona, F.Javier; Maqueda, María; Velásquez, Adriana; Gómez, Antonio; Labernadie, Anna; Lugo, Roberto; Gabasa, Marta; Rigat-Brugarolas, Luis G.; Trepat, Xavier; Ramírez, Josep; Moran, Sebastian; Vidal, Enrique; Reguart, Noemí; Perera, Alexandre; Esteller, Manel; Alcaraz, Jordi

    2015-01-01

    Epigenetic changes through altered DNA methylation have been implicated in critical aspects of tumor progression, and have been extensively studied in a variety of cancer types. In contrast, our current knowledge of the aberrant genomic DNA methylation in tumor-associated fibroblasts (TAFs) or other stromal cells that act as critical coconspirators of tumor progression is very scarce. To address this gap of knowledge, we conducted genome-wide DNA methylation profiling on lung TAFs and paired control fibroblasts (CFs) from non-small cell lung cancer patients using the HumanMethylation450 microarray. We found widespread DNA hypomethylation concomitant with focal gain of DNA methylation in TAFs compared to CFs. The aberrant DNA methylation landscape of TAFs had a global impact on gene expression and a selective impact on the TGF-β pathway. The latter included promoter hypermethylation-associated SMAD3 silencing, which was associated with hyperresponsiveness to exogenous TGF-β1 in terms of contractility and extracellular matrix deposition. In turn, activation of CFs with exogenous TGF-β1 partially mimicked the epigenetic alterations observed in TAFs, suggesting that TGF-β1 may be necessary but not sufficient to elicit such alterations. Moreover, integrated pathway-enrichment analyses of the DNA methylation alterations revealed that a fraction of TAFs may be bone marrow-derived fibrocytes. Finally, survival analyses using DNA methylation and gene expression datasets identified aberrant DNA methylation on the EDARADD promoter sequence as a prognostic factor in non-small cell lung cancer patients. Our findings shed light on the unique origin and molecular alterations underlying the aberrant phenotype of lung TAFs, and identify a stromal biomarker with potential clinical relevance. PMID:26449251

  18. Fibroblasts weaken the anti-tumor effect of gefitinib on co-cultured non-small cell lung cancer cells

    Institute of Scientific and Technical Information of China (English)

    Yong Xiao; Wang Peiqin; Jiang Tao; Yu Wenchen; Shang Yan; Han Yiping; Zhang Pingping

    2014-01-01

    Background Non-small cell lung cancer (NSCLC) is the most common lung malignancy worldwide.The metastatic potential of NSCLC cells has been shown to be associated with the tumor microenvironment,which consists of tumor cells,stroma,blood vessels,immune infiltrates and the extracellular matrix.Fibroblasts can produce numerous extraceilular matrix molecules and growth factors.Gefitinib has been evaluated as a first-line treatment in selected patients,and it has shown favorable efficacy especially in NSCLC,but it is not effective for everyone.Methods In this study,we examined the antitumor activity of gefitinib on lung fibroblasts co-cultured of lung cancer cells.A series of co-culture experiments that employed cell counting kit-8 (CCK8),transwells,real-time polymerase chain reaction (RT-PCR) and Western blotting with HFL-1 fibroblasts and A549 human lung carcinoma cells were performed to learn more about tumor cell proliferation,migration and invasion; and to determine any change of epithelial mesenchymal transition (EMT)-associated tumor markers vimentin,matrix metallopro-teinase 2 (MMP2) and chemotaxis cytokines receptor 4 (CXCR4) mRNA levels.Results A549 cell proliferation in the presence of HFL-1 cells was not significantly increased compared with A549 cells alone,but A549 cell spheroid body formation was increased after co-culture,and treatment with gefitinib increased further.Our study also revealed that fibroblasts attenuated the lung cancer cell inhibition ratio of migration and invasion after gefitinib treatment in vitro.To further study this mechanism,RT-PCR analysis showed that vimentin,MMP2 and CXCR4 mRNA levels were more highly expressed in the lung cancer cells after co-culture,but did not obviously decrease compared with the control cells following gefitinib treatment.This suggests the mechanism by which fibroblasts attenuate gefitinib-induced expression of EMT-associated tumor markers.Finally,our results demonstrated that co-culture with A549 lung

  19. Oridonin induces apoptosis and senescence in colorectal cancer cells by increasing histone hyperacetylation and regulation of p16, p21, p27 and c-myc

    Directory of Open Access Journals (Sweden)

    Zhao Ying-Zheng

    2010-11-01

    Full Text Available Abstract Background Oridonin, a tetracycline diterpenoid compound, has the potential antitumor activities. Here, we evaluate the antitumor activity and action mechanisms of oridonin in colorectal cancer. Methods Effects of oridonin on cell proliferation were determined by using a CCK-8 Kit. Cell cycle distribution was determined by flow cytometry. Apoptosis was examined by analyzing subdiploid population and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Senescent cells were determined by senescence-associated β-galactosidase activity analysis. Semi-quantitative RT-PCR was used to examine the changes of mRNA of p16, p21, p27 and c-myc. The concomitant changes of protein expression were analyzed with Western blot. Expression of AcH3 and AcH4 were examined by immunofluorescence staining and Western blots. Effects of oridonin on colony formation of SW1116 were examined by Soft Agar assay. The in vivo efficacy of oridonin was detected using a xenograft colorectal cancer model in nude mice. Results Oridonin induced potent growth inhibition, cell cycle arrest, apoptosis, senescence and colony-forming inhibition in three colorectal cancer cell lines in a dose-dependent manner in vitro. Daily i.p. injection of oridonin (6.25, 12.5 or 25 mg/kg for 28 days significantly inhibited the growth of SW1116 s.c. xenografts in BABL/C nude mice. With western blot and reverse transcription-PCR, we further showed that the antitumor activities of oridonin correlated with induction of histone (H3 and H4 hyperacetylation, activation of p21, p27 and p16, and suppression of c-myc expression. Conclusion Oridonin possesses potent in vitro and in vivo anti-colorectal cancer activities that correlated with induction of histone hyperacetylation and regulation of pathways critical for maintaining growth inhibition and cell cycle arrest. Therefore, oridonin may represent a novel therapeutic option in colorectal cancer treatment.

  20. Oridonin induces apoptosis and senescence in colorectal cancer cells by increasing histone hyperacetylation and regulation of p16, p21, p27 and c-myc

    International Nuclear Information System (INIS)

    Oridonin, a tetracycline diterpenoid compound, has the potential antitumor activities. Here, we evaluate the antitumor activity and action mechanisms of oridonin in colorectal cancer. Effects of oridonin on cell proliferation were determined by using a CCK-8 Kit. Cell cycle distribution was determined by flow cytometry. Apoptosis was examined by analyzing subdiploid population and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Senescent cells were determined by senescence-associated β-galactosidase activity analysis. Semi-quantitative RT-PCR was used to examine the changes of mRNA of p16, p21, p27 and c-myc. The concomitant changes of protein expression were analyzed with Western blot. Expression of AcH3 and AcH4 were examined by immunofluorescence staining and Western blots. Effects of oridonin on colony formation of SW1116 were examined by Soft Agar assay. The in vivo efficacy of oridonin was detected using a xenograft colorectal cancer model in nude mice. Oridonin induced potent growth inhibition, cell cycle arrest, apoptosis, senescence and colony-forming inhibition in three colorectal cancer cell lines in a dose-dependent manner in vitro. Daily i.p. injection of oridonin (6.25, 12.5 or 25 mg/kg) for 28 days significantly inhibited the growth of SW1116 s.c. xenografts in BABL/C nude mice. With western blot and reverse transcription-PCR, we further showed that the antitumor activities of oridonin correlated with induction of histone (H3 and H4) hyperacetylation, activation of p21, p27 and p16, and suppression of c-myc expression. Oridonin possesses potent in vitro and in vivo anti-colorectal cancer activities that correlated with induction of histone hyperacetylation and regulation of pathways critical for maintaining growth inhibition and cell cycle arrest. Therefore, oridonin may represent a novel therapeutic option in colorectal cancer treatment

  1. Fibroblast Activation Protein Expression by Stromal Cells and Tumor-Associated Macrophages in Human Breast Cancer

    Science.gov (United States)

    Julia, Tchou; Zhang Paul, J; Yingtao, Bi; Celine, Satija; Rajrupa, Marjumdar; Stephen, TL; Lo, A; Haiying, Chen; Carolyn, Mies; June, Carl H; Jose, Conejo-Garcia; Ellen, Puré

    2013-01-01

    Summary Fibroblast activation protein (FAP) has long been known to be expressed in the stroma of breast cancer. However, very little is known if the magnitude of FAP expression within the stroma may have prognostic value and reflect the heterogeneous biology of the tumor cell. An earlier study had suggested that stromal FAP expression in breast cancer was inversely proportional to prognosis. We, therefore, hypothesized that stromal FAP expression may correlate with clinicopathologic variables and may serve as an adjunct prognostic factor in breast cancer. We evaluated the expression of FAP in a panel of breast cancer tissues (n=52) using a combination of immunostain analyses at the tissue and single cell level using freshly frozen or freshly digested human breast tumor samples respectively. Our results showed that FAP expression was abundantly expressed in the stroma across all breast cancer subtypes without significant correlation with clinicopathologic factors. We further identified a subset of FAP positive or FAP+ stromal cells that also expressed CD45, a pan-leukocyte marker. Using freshly dissociated human breast tumor specimens (n=5), we demonstrated that some of these FAP+ CD45+ cells were CD11b+CD14+MHC-II+ indicating that they were likely tumor associated macrophages (TAMs). Although FAP+CD45+ cells have been demonstrated in the mouse tumor stroma, our results demonstrating that human breast TAMs expressed FAP was novel and suggested that existing and future FAP directed therapy may have dual therapeutic benefits targeting both stromal mesenchymal cells and immune cells such as TAMs. More work is needed to explore the role of FAP as a potential targetable molecule in breast cancer treatment. PMID:24074532

  2. Radiosensitivity of skin fibroblasts from atomic bomb survivors with and without breast cancer

    International Nuclear Information System (INIS)

    Fibroblasts were established in vitro from skin biopsies obtained from 55 women and 1 man with or without breast cancer and with or without exposure to radiation from the atomic bomb explosion in Hiroshima. The radiosensitivity of these cells was evaluated by clonogenic assays after exposure to X-rays or to fission neutrons from a 252Cf source. Data were fitted to a multitarget model, S/S0 = A [1 - (1 - ekD)N], for both X-ray and neutron dose-survival curves. A single hit model, S/S0 = AekD, fits the neutron dose-survival responses as well. There were no differences in the means or variances of radiosensitivity between exposed and nonexposed groups or between patients with or without breast cancer. Hence, although the sample is not large, it provides no support for the hypothesis that atomic bomb radiation preferentially induces breast cancer in women whose cells in vitro are sensitive to cell killing by radiation

  3. Radiosensitivity of skin fibroblasts from atomic bomb survivors with and without breast cancer

    International Nuclear Information System (INIS)

    Fibroblasts were established in vitro from skin biopsies obtained from 55 women and one man with or without breast cancer and with or without exposure to radiation from the atomic bomb explosion in Hiroshima. The radiosensitivity of these cells was evaluated by clonogenic assays after exposure to X rays or to fission neutrons from a 252Cf source. Data were fitted to a multitarget model, S/S0 = A[1-(1-ekD)N], for both X-ray and neutron dose-survival curves. A single-hit model, S/S0 = AekD, fits the neutron dose-survival responses as well. These was no difference in the means or variances of radiosensitivity between exposed and nonexposed groups, or between patients with or without breast cancer. Hence, although the sample is not large, it provides no support for the hypothesis that A-bomb radiation preferentially induces breast cancer in women whose cells in vitro are sensitive to cell killing by radiation. (author)

  4. Simultaneous Expression of Cancer Stem Cell-Like Properties and Cancer-Associated Fibroblast-Like Properties in a Primary Culture of Breast Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Mami; Inoue, Takahiro; Shirai, Takuma; Takamatsu, Kazuhiko; Kunihiro, Shiori; Ishii, Hirokazu [Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, Kobe 650-0047 (Japan); Nishikata, Takahito, E-mail: nisikata@konan-u.ac.jp [Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, Kobe 650-0047 (Japan); Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, Kobe 650-0047 (Japan)

    2014-07-31

    The importance of cancer-associated fibroblasts (CAFs) in cancer biology has been recently highlighted owing to their critical roles in cancer growth, progression, metastasis, and therapeutic resistance. We have previously established a primary culture of breast cancer cells, which showed epithelial-mesenchymal transition and cancer stem cell-like properties. In this study, we found that the primary culture also showed CAF-like properties. For example, hypoxia inducible factor 1α (HIF1A) and its downstream genes, nuclear factor-kappa B2 (NF-κB2) and BCL2/adenovirus E1B 19 kd-interacting protein 3 (BNIP3), and many enzymes involved in glycolysis, such as GAPDH, LDH, PGAM1, and PKM2, were highly overexpressed in the primary culture. Moreover, media conditioned with the primary culture cells enhanced the growth of breast cancer cells. Similar to previous CAF studies, this enhancement suggested to be occurred through fibroblast growth factor signaling. This MCKH primary culture cell, which showed simultaneous expression of tumorigenic and CAF properties, offers a unique experimental system for studying the biology of CAFs.

  5. Simultaneous Expression of Cancer Stem Cell-Like Properties and Cancer-Associated Fibroblast-Like Properties in a Primary Culture of Breast Cancer Cells

    International Nuclear Information System (INIS)

    The importance of cancer-associated fibroblasts (CAFs) in cancer biology has been recently highlighted owing to their critical roles in cancer growth, progression, metastasis, and therapeutic resistance. We have previously established a primary culture of breast cancer cells, which showed epithelial-mesenchymal transition and cancer stem cell-like properties. In this study, we found that the primary culture also showed CAF-like properties. For example, hypoxia inducible factor 1α (HIF1A) and its downstream genes, nuclear factor-kappa B2 (NF-κB2) and BCL2/adenovirus E1B 19 kd-interacting protein 3 (BNIP3), and many enzymes involved in glycolysis, such as GAPDH, LDH, PGAM1, and PKM2, were highly overexpressed in the primary culture. Moreover, media conditioned with the primary culture cells enhanced the growth of breast cancer cells. Similar to previous CAF studies, this enhancement suggested to be occurred through fibroblast growth factor signaling. This MCKH primary culture cell, which showed simultaneous expression of tumorigenic and CAF properties, offers a unique experimental system for studying the biology of CAFs

  6. HiJAK’d Signaling; the STAT3 Paradox in Senescence and Cancer Progression

    Energy Technology Data Exchange (ETDEWEB)

    Junk, Damian J.; Bryson, Benjamin L.; Jackson, Mark W., E-mail: mark.w.jackson@case.edu [Department of Pathology, Case Western Reserve University, Case Comprehensive Cancer Center, 2103 Cornell Road, WRB 3-134, Cleveland, OH 44106 (United States)

    2014-03-26

    Clinical and epidemiological data have associated chronic inflammation with cancer progression. Most tumors show evidence of infiltrating immune and inflammatory cells, and chronic inflammatory disorders are known to increase the overall risk of cancer development. While immune cells are often observed in early hyperplastic lesions in vivo, there remains debate over whether these immune cells and the cytokines they produce in the developing hyperplastic microenvironment act to inhibit or facilitate tumor development. The interleukin-6 (IL-6) family of cytokines, which includes IL-6 and oncostatin M (OSM), among others (LIF, CT-1, CNTF, and CLC), are secreted by immune cells, stromal cells, and epithelial cells, and regulate diverse biological processes. Each of the IL-6 family cytokines signals through a distinct receptor complex, yet each receptor complex uses a shared gp130 subunit, which is critical for signal transduction following cytokine binding. Activation of gp130 results in the activation of Signal Transducer and Activator of Transcription 3 (STAT3), and the Mitogen-Activated Protein Kinase (MAPK) and Phosphatidylinositol 3-Kinase (PI3K) signaling cascades. Tumor suppressive signaling can often be observed in normal cells following prolonged STAT3 activation. However, there is mounting evidence that the IL-6 family cytokines can contribute to later stages of tumor progression in many ways. Here we will review how the microenvironmental IL-6 family cytokine OSM influences each stage of the transformation process. We discuss the intrinsic adaptations a developing cancer cell must make in order to tolerate and circumvent OSM-mediated growth suppression, as well as the OSM effectors that are hijacked during tumor expansion and metastasis. We propose that combining current therapies with new ones that suppress the signals generated from the tumor microenvironment will significantly impact an oncologist’s ability to treat cancer.

  7. HiJAK’d Signaling; the STAT3 Paradox in Senescence and Cancer Progression

    Directory of Open Access Journals (Sweden)

    Damian J. Junk

    2014-03-01

    Full Text Available Clinical and epidemiological data have associated chronic inflammation with cancer progression. Most tumors show evidence of infiltrating immune and inflammatory cells, and chronic inflammatory disorders are known to increase the overall risk of cancer development. While immune cells are often observed in early hyperplastic lesions in vivo, there remains debate over whether these immune cells and the cytokines they produce in the developing hyperplastic microenvironment act to inhibit or facilitate tumor development. The interleukin-6 (IL-6 family of cytokines, which includes IL-6 and oncostatin M (OSM, among others (LIF, CT-1, CNTF, and CLC, are secreted by immune cells, stromal cells, and epithelial cells, and regulate diverse biological processes. Each of the IL-6 family cytokines signals through a distinct receptor complex, yet each receptor complex uses a shared gp130 subunit, which is critical for signal transduction following cytokine binding. Activation of gp130 results in the activation of Signal Transducer and Activator of Transcription 3 (STAT3, and the Mitogen-Activated Protein Kinase (MAPK and Phosphatidylinositol 3-Kinase (PI3K signaling cascades. Tumor suppressive signaling can often be observed in normal cells following prolonged STAT3 activation. However, there is mounting evidence that the IL-6 family cytokines can contribute to later stages of tumor progression in many ways. Here we will review how the microenvironmental IL-6 family cytokine OSM influences each stage of the transformation process. We discuss the intrinsic adaptations a developing cancer cell must make in order to tolerate and circumvent OSM-mediated growth suppression, as well as the OSM effectors that are hijacked during tumor expansion and metastasis. We propose that combining current therapies with new ones that suppress the signals generated from the tumor microenvironment will significantly impact an oncologist’s ability to treat cancer.

  8. HiJAK’d Signaling; the STAT3 Paradox in Senescence and Cancer Progression

    International Nuclear Information System (INIS)

    Clinical and epidemiological data have associated chronic inflammation with cancer progression. Most tumors show evidence of infiltrating immune and inflammatory cells, and chronic inflammatory disorders are known to increase the overall risk of cancer development. While immune cells are often observed in early hyperplastic lesions in vivo, there remains debate over whether these immune cells and the cytokines they produce in the developing hyperplastic microenvironment act to inhibit or facilitate tumor development. The interleukin-6 (IL-6) family of cytokines, which includes IL-6 and oncostatin M (OSM), among others (LIF, CT-1, CNTF, and CLC), are secreted by immune cells, stromal cells, and epithelial cells, and regulate diverse biological processes. Each of the IL-6 family cytokines signals through a distinct receptor complex, yet each receptor complex uses a shared gp130 subunit, which is critical for signal transduction following cytokine binding. Activation of gp130 results in the activation of Signal Transducer and Activator of Transcription 3 (STAT3), and the Mitogen-Activated Protein Kinase (MAPK) and Phosphatidylinositol 3-Kinase (PI3K) signaling cascades. Tumor suppressive signaling can often be observed in normal cells following prolonged STAT3 activation. However, there is mounting evidence that the IL-6 family cytokines can contribute to later stages of tumor progression in many ways. Here we will review how the microenvironmental IL-6 family cytokine OSM influences each stage of the transformation process. We discuss the intrinsic adaptations a developing cancer cell must make in order to tolerate and circumvent OSM-mediated growth suppression, as well as the OSM effectors that are hijacked during tumor expansion and metastasis. We propose that combining current therapies with new ones that suppress the signals generated from the tumor microenvironment will significantly impact an oncologist’s ability to treat cancer

  9. Cancer Associated Fibroblasts express pro-inflammatory factors in human breast and ovarian tumors

    Energy Technology Data Exchange (ETDEWEB)

    Erez, Neta, E-mail: netaerez@post.tau.ac.il [Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel-Aviv 69978 (Israel); Glanz, Sarah [Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel-Aviv 69978 (Israel); Raz, Yael [Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel-Aviv 69978 (Israel); Department of Obstetrics and Gynecology, LIS Maternity Hospital, Tel Aviv Sourasky Medical Center, affiliated with Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel); Avivi, Camilla [Department of Pathology, Sheba Medical Center, Tel Hashomer, affiliated with Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel); Barshack, Iris [Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel-Aviv 69978 (Israel); Department of Pathology, Sheba Medical Center, Tel Hashomer, affiliated with Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel)

    2013-08-02

    Highlights: •CAFs in human breast and ovarian tumors express pro-inflammatory factors. •Expression of pro-inflammatory factors correlates with tumor invasiveness. •Expression of pro-inflammatory factors is associated with NF-κb activation in CAFs. -- Abstract: Inflammation has been established in recent years as a hallmark of cancer. Cancer Associated Fibroblasts (CAFs) support tumorigenesis by stimulating angiogenesis, cancer cell proliferation and invasion. We previously demonstrated that CAFs also mediate tumor-enhancing inflammation in a mouse model of skin carcinoma. Breast and ovarian carcinomas are amongst the leading causes of cancer-related mortality in women and cancer-related inflammation is linked with both these tumor types. However, the role of CAFs in mediating inflammation in these malignancies remains obscure. Here we show that CAFs in human breast and ovarian tumors express high levels of the pro-inflammatory factors IL-6, COX-2 and CXCL1, previously identified to be part of a CAF pro-inflammatory gene signature. Moreover, we show that both pro-inflammatory signaling by CAFs and leukocyte infiltration of tumors are enhanced in invasive ductal carcinoma as compared with ductal carcinoma in situ. The pro-inflammatory genes expressed by CAFs are known NF-κB targets and we show that NF-κB is up-regulated in breast and ovarian CAFs. Our data imply that CAFs mediate tumor-promoting inflammation in human breast and ovarian tumors and thus may be an attractive target for stromal-directed therapeutics.

  10. Metformin lowers the threshold for stress-induced senescence: a role for the microRNA-200 family and miR-205.

    Science.gov (United States)

    Cufí, Sílvia; Vazquez-Martin, Alejandro; Oliveras-Ferraros, Cristina; Quirantes, Rosa; Segura-Carretero, Antonio; Micol, Vicente; Joven, Jorge; Bosch-Barrera, Joaquim; Del Barco, Sonia; Martin-Castillo, Begoña; Vellon, Luciano; Menendez, Javier A

    2012-03-15

    We have tested the hypothesis that the antidiabetic biguanide metformin can be used to manipulate the threshold for stress-induced senescence (SIS), thus accelerating the onset of cancer-protective cellular senescence in response to oncogenic stimuli. Using senescence-prone murine embryonic fibroblasts (MEFs), we assessed whether metformin treatment modified the senescence phenotype that is activated in response to DNA damaging inducers. Metformin significantly enhanced the number of MEFs entering a senescent stage in response to doxorubicin, an anthracycline that induces cell senescence by activating DNA damage signaling pathways (e.g., ATM/ATR) in a reactive oxygen species (ROS)-dependent manner. Using WI-38 and BJ-1 human diploid fibroblasts (HDFs), we explored whether metformin supplementation throughout their entire replicative lifespan may promote the early appearance of the biomarkers of replicative senescence. Chronic metformin significantly reduced HDFs' lifespan by accelerating both the loss of replicative potential and the acquisition of replicative senescence-related biomarkers (e.g., enlarged and flattened cell shapes, loss of arrayed arrangement, accumulation of intracellular and extracellular debris and SA-β-gal-positive staining). Metformin functioned as a bona fide stressful agent, inducing monotonic, dose-dependent, SIS-like responses in BJ-1 HDFs, which are highly resistant to ROS-induced premature senescence. Metformin-induced SIS in BJ-1 fibroblasts was accompanied by the striking activation of several microRNAs belonging to the miR-200s family (miR-200a, miR-141 and miR429) and miR-205, thus mimicking a recently described ability of ROS to chemosensitize cancer cells by specifically upregulating anti-EMT (epithelial-to-mesenchymal transition) miR-200s. Because the unlimited proliferative potential of stem cells results from their metabolic refractoriness to SIS, we finally tested if metformin treatment could circumvent the stress (e.g., ROS

  11. Paracrine effect of GTP cyclohydrolase and angiopoietin-1 interaction in stromal fibroblasts on tumor Tie2 activation and breast cancer growth.

    Science.gov (United States)

    Chen, Liye; Zeng, Xin; Kleibeuker, Esther; Buffa, Francesca; Barberis, Alessandro; Leek, Russell D; Roxanis, Ioannis; Zhang, Wei; Worth, Andrew; Beech, John S; Harris, Adrian L; Cai, Shijie

    2016-02-23

    Cancer-associated fibroblasts (CAFs) play a key role in promoting tumor growth, acting through complex paracrine regulation. GTP cyclohydrolase (GTPCH) expression for tetrahydrobiopterin synthesis in tumor stroma is implicated in angiogenesis and tumor development. However, the clinical significance of GTPCH expression in breast cancer is still elusive and how GTPCH regulates stromal fibroblast and tumor cell communication remains unknown. We found that GTPCH was upregulated in breast CAFs and epithelia, and high GTPCH RNA was significantly correlated with larger high grade tumors and worse prognosis. In cocultures, GTPCH expressing fibroblasts stimulated breast cancer cell proliferation and motility, cancer cell Tie2 phosphorylation and consequent downstream pathway activation. GTPCH interacted with Ang-1 in stromal fibroblasts and enhanced Ang-1 expression and function, which in turn phosphorylated tumor Tie2 and induced cell proliferation. In coimplantation xenografts, GTPCH in fibroblasts enhanced tumor growth, upregulating Ang-1 and alpha-smooth muscle actin mainly in fibroblast-like cells. GTPCH inhibition resulted in the attenuation of tumor growth and angiogenesis. GTPCH/Ang-1 interaction in stromal fibroblasts and activation of Tie2 on breast tumor cells could play an important role in supporting breast cancer growth. GTPCH may be an important mechanism of paracrine tumor growth and hence a target for therapy in breast cancer. PMID:26814432

  12. The mRNA decay factor tristetraprolin (TTP) induces senescence in human papillomavirus-transformed cervical cancer cells by targeting E6-AP ubiquitin ligase

    OpenAIRE

    Sanduja, Sandhya; Kaza, Vimala; Dixon, Dan A.

    2009-01-01

    The RNA-binding protein tristetraprolin (TTP) regulates expression of many cancer-associated and proinflammatory factors through binding AU-rich elements (ARE) in the 3'-untranslated region (3'UTR) and facilitating rapid mRNA decay. Here we report on the ability of TTP to act in an anti-proliferative capacity in HPV18-positive HeLa cells by inducing senescence. HeLa cells maintain a dormant p53 pathway and elevated telomerase activity resulting from HPV-mediated transformation, whereas TTP ex...

  13. Oncogene-induced senescence in melanocytes

    OpenAIRE

    Leikam, Claudia

    2013-01-01

    Melanoma is the most aggressive skin cancer with very limited treatment options. Upon appearance of metastases chemotherapeutics are used to either kill or slow down the growth of cancer cells by inducing apoptosis or senescence, respectively. With melanomas originating from melanocytes, it is vital to elucidate the mechanisms that distinguish senescence induction from proliferation and tumourigenicity. Xmrk (Xiphophorus melanoma receptor kinase), the fish orthologue of the human epidermal gr...

  14. Breast cancer stromal fibroblasts promote the generation of CD44+CD24- cells through SDF-1/CXCR4 interaction

    Directory of Open Access Journals (Sweden)

    Zhang Huanle

    2010-06-01

    Full Text Available Abstract Background Breast cancer stem cells (BCSCs have been recently identified in breast carcinoma as CD44+CD24- cells, which exclusively retain tumorigenic activity and display stem cell-like properties. Using a mammosphere culture technique, MCF7 mammosphere cells are found to enrich breast cancer stem-like cells expressing CD44+CD24-. The stromal cells are mainly constituted by fibroblasts within a breast carcinoma, yet little is known of the contributions of the stromal cells to BCSCs. Methods Carcinoma-associated fibroblasts (CAFs and normal fibroblasts (NFs were isolated and identified by immunohistochemistry. MCF7 mammosphere cells were co-cultured with different stromal fibroblasts by a transwell cocultured system. Flow cytometry was used to measure CD44 and CD24 expression status on MCF7. ELISA (enzyme-linked immunosorbent assay was performed to investigate the production of stromal cell-derived factor 1 (SDF-1 in mammosphere cultures subject to various treatments. Mammosphere cells were injected with CAFs and NFs to examine the efficiency of tumorigenity in NOD/SCID mice. Results CAFs derived from breast cancer patients were found to be positive for α-smooth muscle actin (α-SMA, exhibiting the traits of myofibroblasts. In addition, CAFs played a central role in promoting the proliferation of CD44+CD24- cells through their ability to secrete SDF-1, which may be mediated to SDF-1/CXCR4 signaling. Moreover, the tumorigenicity of mammosphere cells with CAFs significantly increased as compared to that of mammosphere cells alone or with NFs. Conclusion We for the first time investigated the effects of stromal fibroblasts on CD44+CD24- cells and our findings indicated that breast CAFs contribute to CD44+CD24- cell proliferation through the secretion of SDF-1, and which may be important target for therapeutic approaches.

  15. p53 isoforms, Δ133p53 and p53β, are endogenous regulators of replicative cellular senescence

    OpenAIRE

    Fujita, Kaori; Mondal, Abdul M.; Horikawa, Izumi; Nguyen, Giang H.; Kumamoto, Kensuke; Sohn, Jane J.; Bowman, Elise D.; Mathe, Ewy A.; Schetter, Aaron J.; Pine, Sharon R.; Ji, Helen; Vojtesek, Borivoj; Bourdon, Jean-Christophe; Lane, David P; Harris, Curtis C.

    2009-01-01

    The finite proliferative potential of normal human cells leads to replicative cellular senescence, which is a critical barrier to tumour progression in vivo1–3. We show that human p53 isoforms (Δ133p53 and p53β)4 constitute an endogenous regulatory mechanism for p53-mediated replicative senescence. Induced p53β and diminished Δ133p53 were associated with replicative senescence, but not oncogene-induced senescence, in normal human fibroblasts. The replicatively senescent fibroblasts also expre...

  16. Characterization of human lung cancer-associated fibroblasts in three-dimensional in vitro co-culture model

    International Nuclear Information System (INIS)

    Highlights: ► We established three patient-paired sets of CAFs and NFs. ► CAFs and NFs were analyzed using three-dimensional co-culture experiments. ► CAFs clearly enhanced collagen gel contraction. ► CAFs showed higher α-SMA expression than NFs. ► CAFs were implicated in invasion and differentiation of lung cancer cells. -- Abstract: Lung cancer is the most common cause of cancer-related death worldwide. Stromal cancer-associated fibroblasts (CAFs) play crucial roles in carcinogenesis, proliferation, invasion, and metastasis of non-small cell lung carcinoma, and targeting of CAFs could be a novel strategy for cancer treatment. However, the characteristics of human CAFs still remain to be better defined. In this study, we established patient-matched CAFs and normal fibroblasts (NFs), from tumoral and non-tumoral portions of resected lung tissue from lung cancer patients. CAFs showed higher α-smooth muscle actin (α-SMA) expression than NFs, and CAFs clearly enhanced collagen gel contraction. Furthermore, we employed three-dimensional co-culture assay with A549 lung cancer cells, where CAFs were more potent in inducing collagen gel contraction. Hematoxylin and eosin staining of co-cultured collagen gel revealed that CAFs had the potential to increase invasion of A549 cells compared to NFs. These observations provide evidence that lung CAFs have the tumor-promoting capacity distinct from NFs.

  17. NKG2D ligands mediate immunosurveillance of senescent cells.

    Science.gov (United States)

    Sagiv, Adi; Burton, Dominick G A; Moshayev, Zhana; Vadai, Ezra; Wensveen, Felix; Ben-Dor, Shifra; Golani, Ofra; Polic, Bojan; Krizhanovsky, Valery

    2016-02-01

    Cellular senescence is a stress response mechanism that limits tumorigenesis and tissue damage. Induction of cellular senescence commonly coincides with an immunogenic phenotype that promotes self-elimination by components of the immune system, thereby facilitating tumor suppression and limiting excess fibrosis during wound repair. The mechanisms by which senescent cells regulate their immune surveillance are not completely understood. Here we show that ligands of an activating Natural Killer (NK) cell receptor (NKG2D), MICA and ULBP2 are consistently up-regulated following induction of replicative senescence, oncogene-induced senescence and DNA damage - induced senescence. MICA and ULBP2 proteins are necessary for efficient NK-mediated cytotoxicity towards senescent fibroblasts. The mechanisms regulating the initial expression of NKG2D ligands in senescent cells are dependent on a DNA damage response, whilst continuous expression of these ligands is regulated by the ERK signaling pathway. In liver fibrosis, the accumulation of senescent activated stellate cells is increased in mice lacking NKG2D receptor leading to increased fibrosis. Overall, our results provide new insights into the mechanisms regulating the expression of immune ligands in senescent cells and reveal the importance of NKG2D receptor-ligand interaction in protecting against liver fibrosis. PMID:26878797

  18. Protein markers of cancer-associated fibroblasts and tumor-initiating cells reveal subpopulations in freshly isolated ovarian cancer ascites

    Directory of Open Access Journals (Sweden)

    Wintzell My

    2012-08-01

    Full Text Available Abstract Background In ovarian cancer, massive intraperitoneal dissemination is due to exfoliated tumor cells in ascites. Tumor-initiating cells (TICs or cancer stem cells and cells showing epithelial-mesenchymal-transition (EMT are particularly implicated. Spontaneous spherical cell aggregates are sometimes observed, but although similar to those formed by TICs in vitro, their significance is unclear. Methods Cells freshly isolated from malignant ascites were separated into sphere samples (S-type samples, n=9 and monolayer-forming single-cell suspensions (M-type, n=18. Using western blot, these were then compared for expression of protein markers of EMT, TIC, and of cancer-associated fibroblasts (CAFs. Results S-type cells differed significantly from M-type by expressing high levels of E-cadherin and no or little vimentin, integrin-β3 or stem cell transcription factor Oct-4A. By contrast, M-type samples were enriched for CD44, Oct-4A and for CAF markers. Independently of M- and S-type, there was a strong correlation between TIC markers Nanog and EpCAM. The CAF marker α-SMA correlated with clinical stage IV. This is the first report on CAF markers in malignant ascites and on SUMOylation of Oct-4A in ovarian cancer. Conclusions In addition to demonstrating potentially high levels of TICs in ascites, the results suggest that the S-type population is the less tumorigenic one. Nanoghigh/EpCAMhigh samples represent a TIC subset which may be either M- or S-type, and which is separate from the CD44high/Oct-4Ahigh subset observed only in M-type samples. This demonstrates a heterogeneity in TIC populations in vivo which has practical implications for TIC isolation based on cell sorting. The biological heterogeneity will need to be addressed in future therapeutical strategies.

  19. Protein markers of cancer-associated fibroblasts and tumor-initiating cells reveal subpopulations in freshly isolated ovarian cancer ascites

    International Nuclear Information System (INIS)

    In ovarian cancer, massive intraperitoneal dissemination is due to exfoliated tumor cells in ascites. Tumor-initiating cells (TICs or cancer stem cells) and cells showing epithelial-mesenchymal-transition (EMT) are particularly implicated. Spontaneous spherical cell aggregates are sometimes observed, but although similar to those formed by TICs in vitro, their significance is unclear. Cells freshly isolated from malignant ascites were separated into sphere samples (S-type samples, n=9) and monolayer-forming single-cell suspensions (M-type, n=18). Using western blot, these were then compared for expression of protein markers of EMT, TIC, and of cancer-associated fibroblasts (CAFs). S-type cells differed significantly from M-type by expressing high levels of E-cadherin and no or little vimentin, integrin-β3 or stem cell transcription factor Oct-4A. By contrast, M-type samples were enriched for CD44, Oct-4A and for CAF markers. Independently of M- and S-type, there was a strong correlation between TIC markers Nanog and EpCAM. The CAF marker α-SMA correlated with clinical stage IV. This is the first report on CAF markers in malignant ascites and on SUMOylation of Oct-4A in ovarian cancer. In addition to demonstrating potentially high levels of TICs in ascites, the results suggest that the S-type population is the less tumorigenic one. Nanoghigh/EpCAMhigh samples represent a TIC subset which may be either M- or S-type, and which is separate from the CD44high/Oct-4Ahigh subset observed only in M-type samples. This demonstrates a heterogeneity in TIC populations in vivo which has practical implications for TIC isolation based on cell sorting. The biological heterogeneity will need to be addressed in future therapeutical strategies

  20. Activated FXR Inhibits Leptin Signaling and Counteracts Tumor-promoting Activities of Cancer-Associated Fibroblasts in Breast Malignancy.

    Science.gov (United States)

    Giordano, Cinzia; Barone, Ines; Vircillo, Valentina; Panza, Salvatore; Malivindi, Rocco; Gelsomino, Luca; Pellegrino, Michele; Rago, Vittoria; Mauro, Loredana; Lanzino, Marilena; Panno, Maria Luisa; Bonofiglio, Daniela; Catalano, Stefania; Andò, Sebastiano

    2016-01-01

    Cancer-associated fibroblasts (CAFs), the principal components of the tumor stroma, play a central role in cancer development and progression. As an important regulator of the crosstalk between breast cancer cells and CAFs, the cytokine leptin has been associated to breast carcinogenesis. The nuclear Farnesoid X Receptor-(FXR) seems to exert an oncosuppressive role in different tumors, including breast cancer. Herein, we demonstrated, for the first time, that the synthetic FXR agonist GW4064, inhibiting leptin signaling, affects the tumor-promoting activities of CAFs in breast malignancy. GW4064 inhibited growth, motility and invasiveness induced by leptin as well as by CAF-conditioned media in different breast cancer cell lines. These effects rely on the ability of activated FXR to increase the expression of the suppressor of the cytokine signaling 3 (SOCS3) leading to inhibition of leptin-activated signaling and downregulation of leptin-target genes. In vivo xenograft studies, using MCF-7 cells alone or co-injected with CAFs, showed that GW4064 administration markedly reduced tumor growth. Interestingly, GW4064-treated tumors exhibited decreased levels of leptin-regulated proteins along with a strong staining intensity for SOCS3. Thus, FXR ligands might represent an emerging potential anti-cancer therapy able to block the tumor supportive role of activated fibroblasts within the breast microenvironment. PMID:26899873

  1. Essential roles of the interaction between cancer cell-derived chemokine, CCL4, and intra-bone CCR5-expressing fibroblasts in breast cancer bone metastasis.

    Science.gov (United States)

    Sasaki, Soichiro; Baba, Tomohisa; Nishimura, Tatsunori; Hayakawa, Yoshihiro; Hashimoto, Shin-Ichi; Gotoh, Noriko; Mukaida, Naofumi

    2016-08-01

    From a murine breast cancer cell line, 4T1, we established a subclone, 4T1.3, which consistently metastasizes to bone upon its injection into the mammary fat pad. 4T1.3 clone exhibited similar proliferation rate and migration capacity as the parental clone. However, the intra-bone injection of 4T1.3 clone caused larger tumors than that of the parental cells, accompanied with increases in fibroblast, but not osteoclast or osteoblast numbers. 4T1.3 clone displayed an enhanced expression of a chemokine, CCL4, but not its specific receptor, CCR5. CCL4 shRNA-transfection of 4T1.3 clone had few effects on its in vitro properties, but reduced the tumorigenicity arising from the intra-bone injection. Moreover, intra-bone injection of 4T1.3 clone caused smaller tumors in mice deficient in CCR5 or those receiving CCR5 antagonist than in wild-type mice. The reduced tumor formation was associated with attenuated accumulation of CCR5-positive fibroblasts expressing connective tissue growth factor (CTGF)/CCN2. Tumor cell-derived CCL4 could induce fibroblasts to express CTGF/CCN2, which could support 4T1.3 clone proliferation under hypoxic culture conditions. Thus, the CCL4-CCR5 axis can contribute to breast cancer metastasis to bone by mediating the interaction between cancer cells and fibroblasts in bone cavity. PMID:27177471

  2. The Apoptotic Effects of the P300 Activator on Breast Cancer and Lung Fibroblast Cell Lines

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Salahshoor

    2013-10-01

    Full Text Available Background: P300 is an enzyme that acetylates histones during stress. It alsoacetylates several non-histone proteins, including P53 which is the most important tumorsuppressor gene. P53 plays an important role in the apoptosis of tumor cells. Hereby,this study describes the potency of cholera toxin B subunit as a P300 activator to induceapoptosis in a breast cancer cell line (MCF-7 and a lung fibroblast cell line (MRC-5as a non-tumorigenic control sample. Methods: MCF-7 and MRC-5 were cultured in RPMI-1640 and treated with orwithout cholera toxin B subunit at the concentration of 85.43 μmol/L, based on the half-maximal inhibitory concentration index at different times (24, 48 and 72 h. Thepercentage of apoptotic cells was measured by flow cytometry. Real-time quantitativeRT-PCR was performed to estimate the mRNA expression of P300 in MCF-7 and MRC-5 with cholera toxin B subunit at different times. We used the ELISA and Bradford proteintechniques to detect levels of total and acetylated P53 protein generated in MCF-7 andMRC-5. Results: Our findings indicated that the cholera toxin B subunit effectively andsignificantly induced more apoptosis in MCF-7 compared to MRC-5. We showed thatexpression of P300 up-regulated by increasing the time of the cholera toxin B subunittreatment in MCF-7 but not in MRC-5. In addition, the acetylated and total P53protein levels increased more in MCF-7 cells than in MRC-5 cells.Conclusion: Cholera toxin B subunit induced significant cell death in MCF-7, butit could be well tolerated in MRC-5. Therefore, cholera toxin B subunit can besuggested as an anti-cancer agent.

  3. Loss of p21Sdi1 expression in senescent cells after DNA damage accompanied with increase of miR-93 expression and reduced p53 interaction with p21Sdi1 gene promoter

    International Nuclear Information System (INIS)

    Highlights: → Reduced p21 expression in senescent cells treated with DNA damaging agents. → Increase of [3H]thymidine and BrdU incorporations in DNA damaged-senescent cells. → Upregulation of miR-93 expression in senescent cells in response to DSB. → Failure of p53 binding to p21 promoter in senescent cells in response to DSB. → Molecular mechanism of increased cancer development in aged than young individuals. -- Abstract: To answer what is a critical event for higher incidence of tumor development in old than young individuals, primary culture of human diploid fibroblasts were employed and DNA damage was induced by doxorubicin or X-ray irradiation. Response to the damage was different between young and old cells; loss of p21sdi1 expression in spite of p53S15 activation in old cells along with [3H]thymidine and BrdU incorporation, but not in young cells. The phenomenon was confirmed by other tissue fibroblasts obtained from different donor ages. Induction of miR-93 expression and reduced p53 binding to p21 gene promoter account for loss of p21sdi1 expression in senescent cells after DNA damage, suggesting a mechanism of in vivo carcinogenesis in aged tissue without repair arrest.

  4. DNA damaging bystander signalling from stem cells, cancer cells and fibroblasts after Cr(VI) exposure and its dependence on telomerase

    International Nuclear Information System (INIS)

    The bystander effect is a feature of low dose radiation exposure and is characterized by a signaling process from irradiated cells to non irradiated cells, which causes DNA and chromosome damage in these 'nearest neighbour' cells. Here we show that a low and short dose of Cr(VI) can induce stem cells, cancer cells and fibroblasts to chronically secrete bystander signals, which cause DNA damage in neighboring cells. The Cr(VI) induced bystander signaling depended on the telomerase status of either cell. Telomerase negative fibroblasts were able to receive DNA damaging signals from telomerase positive or negative fibroblasts or telomerase positive cancer cells. However telomerase positive fibroblasts were resistant to signals from Cr(VI) exposed telomerase positive fibroblasts or cancer cells. Human embryonic stem cells, with positive Oct4 staining as a marker of pluripotency, showed no significant increase of DNA damage from adjacent Cr and mitomycin C exposed fibroblasts whilst those cells that were negatively stained did. This selectivity of DNA damaging bystander signaling could be an important consideration in developing therapies against cancer and in the safety and effectiveness of tissue engineering and transplantation using stem cells.

  5. DNA damaging bystander signalling from stem cells, cancer cells and fibroblasts after Cr(VI) exposure and its dependence on telomerase

    Energy Technology Data Exchange (ETDEWEB)

    Cogan, Nicola [Bristol Implant Research Centre, University of Bristol, Bristol, BS10 5NB (United Kingdom); Baird, Duncan M. [Department of Pathology School of Medicine, Cardiff University, Henry Wellcome Building for Biomedical Research in Wales, Heath Park, Cardiff, CF14 4XN (United Kingdom); Phillips, Ryan [Bristol Implant Research Centre, University of Bristol, Bristol, BS10 5NB (United Kingdom); Crompton, Lucy A.; Caldwell, Maeve A. [Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, BS1 3NY (United Kingdom); Rubio, Miguel A. [Center of Regenerative Medicine in Barcelona, CMRB Dr. Aiguader, 88, 7th Floor, 08003 Barcelona (Spain); Newson, Roger [Radiation and Environmental Science Centre, Focas Institute, Dublin Institute of Technology, Dublin 2 (Ireland); Lyng, Fiona [National Heart and Lung Institute, Imperial College London, London, SW7 2AZ (United Kingdom); Case, C. Patrick, E-mail: c.p.case@bristol.ac.uk [Bristol Implant Research Centre, University of Bristol, Bristol, BS10 5NB (United Kingdom)

    2010-01-05

    The bystander effect is a feature of low dose radiation exposure and is characterized by a signaling process from irradiated cells to non irradiated cells, which causes DNA and chromosome damage in these 'nearest neighbour' cells. Here we show that a low and short dose of Cr(VI) can induce stem cells, cancer cells and fibroblasts to chronically secrete bystander signals, which cause DNA damage in neighboring cells. The Cr(VI) induced bystander signaling depended on the telomerase status of either cell. Telomerase negative fibroblasts were able to receive DNA damaging signals from telomerase positive or negative fibroblasts or telomerase positive cancer cells. However telomerase positive fibroblasts were resistant to signals from Cr(VI) exposed telomerase positive fibroblasts or cancer cells. Human embryonic stem cells, with positive Oct4 staining as a marker of pluripotency, showed no significant increase of DNA damage from adjacent Cr and mitomycin C exposed fibroblasts whilst those cells that were negatively stained did. This selectivity of DNA damaging bystander signaling could be an important consideration in developing therapies against cancer and in the safety and effectiveness of tissue engineering and transplantation using stem cells.

  6. Cancer Associated Fibroblasts in Stage I-IIIA NSCLC: Prognostic Impact and Their Correlations with Tumor Molecular Markers.

    Directory of Open Access Journals (Sweden)

    Thomas K Kilvaer

    Full Text Available Cancer Associated Fibroblasts (CAFs are thought to regulate tumor growth and metastasis. Fibroblast Activating Protein 1 (FAP-1 is a marker for fibroblast activation and by many recognized as the main marker of CAFs. Alpha Smooth Muscle Actin (α-SMA is a general myofibroblast marker, and can be used to identify CAFs. This study investigates the prognostic impact of FAP-1 and α-SMA in non-small cell lung cancer (NSCLC patients and correlates their expression to 105 proteins investigated in the same cohort.Tumor specimens from 536 NSCLC patients were obtained and tissue micro-arrays were constructed. Immunohistochemistry was used to evaluate the expression of FAP-1 and α-SMA and explore their impact on survival and association with other tumor molecular markers in NSCLC patients.High expression of FAP-1, but not α-SMA, in squamous cell carcinoma (SCC, P = 0.043, HR = 0.63 95% CI 0.40-0.99 was significantly associated with increased disease-specific survival. FAP-1 and α-SMA were not significantly correlated to each other. Analyses of FAP-1 and α-SMA associated with other tumor-related proteins revealed histotype-specific correlation patterns.The presence of FAP-1 expressing CAFs is an indicator of positive outcome for NSCLC-SCC patients. In addition, correlation analyses suggest FAP-1 and α-SMA to label different subsets of fibroblasts and their associations with other tumor-related proteins diverge according to histological subtype.

  7. Quantum Dots-Based Immunofluorescent Imaging of Stromal Fibroblasts Caveolin-1 and Light Chain 3B Expression and Identification of Their Clinical Significance in Human Gastric Cancer

    Science.gov (United States)

    He, Yuyu; Zhao, Xianda; Gao, Jun; Fan, Lifang; Yang, Guifang; Cho, William Chi-shing; Chen, Honglei

    2012-01-01

    Caveolin-1 (Cav-1) expression deficiency and autophagy in tumor stromal fibroblasts (hereafter fibroblasts) are involved in tumor proliferation and progression, particularly in breast and prostate cancer. The aim of this study was to detect the expression of fibroblastic Cav-1 and LC3B, markers of autophagy, in gastric cancer (GC) and to analyze their clinical significances. Furthermore, because Epstein-Barr virus (EBV)-associated GC (EBVaGC) is a unique subtype of GC; we compared the differential expression of fibroblastic Cav-1 and LC3B in EBVaGC and non-EBVaGC. Quantum dots (QDs)-based immunofluorescence histochemistry was used to examine the expression of fibroblastic Cav-1 and LC3B in 118 cases of GC with adequate stroma. QDs-based double immunofluorescence labeling was performed to detect the coexpression of Cav-1 and LC3B proteins. EBV-encoded small RNA was detected by QDs-based fluorescence in situ hybridization to identify EBVaGC. Multivariate analysis indicated that low fibroblastic Cav-1 level was an independent prognosticator (p = 0.029) that predicted poorer survival of GC patients. Positive fibroblastic LC3B was correlated with lower invasion (p = 0.032) and was positively associated with Cav-1 expression (r = 0.432, p < 0.001). EBV infection did not affect fibroblastic Cav-1 and LC3B expression. In conclusion, positive fibroblastic LC3B correlates with lower invasion, and low expression of fibroblastic Cav-1 is a novel predictor of poor GC prognosis. PMID:23203033

  8. Cancer-associated fibroblasts promote endometrial cancer growth via activation of interleukin-6/STAT-3/c-Myc pathway.

    Science.gov (United States)

    Subramaniam, Kavita S; Omar, Intan Sofia; Kwong, Soke Chee; Mohamed, Zahurin; Woo, Yin Ling; Mat Adenan, Noor Azmi; Chung, Ivy

    2016-01-01

    Cancer-associated fibroblasts (CAFs) secrete various pro-tumorigenic cytokines, yet the role of these cytokines in the progression of endometrial cancer remains unclear. We found that CAFs isolated from human endometrial cancer (EC) tissues secreted high levels of interleukin-6 (IL-6), which promotes EC cell proliferation in vitro. Neutralizing IL-6 in CAF-conditioned media reduced (47% inhibition) while IL-6 recombinant protein increased cell proliferation (~2.4 fold) of both EC cell lines and primary cultures. IL-6 receptors (IL-6R and gp130) were expressed only in EC epithelial cells but not in CAF, indicating a one-way paracrine signaling. In the presence of CAF-conditioned media, Janus kinase/signal transducers and activators of transcription (JAK/STAT3) pathway was activated in EC cells. Treatment with JAK and STAT3 specific inhibitors, AD412 and STATTIC, respectively, significantly abrogated CAF-mediated cell proliferation, indicating the role of IL-6 activation in EC cell proliferation. We further showed that one of STAT-3 target genes, c-Myc, was highly induced in EC cells after exposure to CAF-conditioned medium at both mRNA (>105-fold vs. control) and protein level (>2-fold vs. control). EC cell proliferation was dependent on c-Myc expression, as RNAi-mediated c-Myc down-regulation led to a significant 46% reduction in cell viability when compared with scrambled control. Interestingly, CAF-conditioned media failed to promote proliferation in EC cells with reduced c-Myc expression, suggesting that CAF-mediated cell proliferation was also dependent on c-Myc expression. Subcutaneous tumor xenograft model showed that EC cells grew at least 1.4 times larger when co-injected with CAF, when compared to those injected with EC cells alone. Mice injected with EC cells with down-regulated c-Myc expression, however, showed at least 2.5 times smaller tumor compared to those in control group. Notably, there was no increase of tumor size when co-injected with CAFs

  9. Cancer-associated fibroblasts promote endometrial cancer growth via activation of interleukin-6/STAT-3/c-Myc pathway

    Science.gov (United States)

    Subramaniam, Kavita S; Omar, Intan Sofia; Kwong, Soke Chee; Mohamed, Zahurin; Woo, Yin Ling; Mat Adenan, Noor Azmi; Chung, Ivy

    2016-01-01

    Cancer-associated fibroblasts (CAFs) secrete various pro-tumorigenic cytokines, yet the role of these cytokines in the progression of endometrial cancer remains unclear. We found that CAFs isolated from human endometrial cancer (EC) tissues secreted high levels of interleukin-6 (IL-6), which promotes EC cell proliferation in vitro. Neutralizing IL-6 in CAF-conditioned media reduced (47% inhibition) while IL-6 recombinant protein increased cell proliferation (~2.4 fold) of both EC cell lines and primary cultures. IL-6 receptors (IL-6R and gp130) were expressed only in EC epithelial cells but not in CAF, indicating a one-way paracrine signaling. In the presence of CAF-conditioned media, Janus kinase/signal transducers and activators of transcription (JAK/STAT3) pathway was activated in EC cells. Treatment with JAK and STAT3 specific inhibitors, AD412 and STATTIC, respectively, significantly abrogated CAF-mediated cell proliferation, indicating the role of IL-6 activation in EC cell proliferation. We further showed that one of STAT-3 target genes, c-Myc, was highly induced in EC cells after exposure to CAF-conditioned medium at both mRNA (>105-fold vs. control) and protein level (>2-fold vs. control). EC cell proliferation was dependent on c-Myc expression, as RNAi-mediated c-Myc down-regulation led to a significant 46% reduction in cell viability when compared with scrambled control. Interestingly, CAF-conditioned media failed to promote proliferation in EC cells with reduced c-Myc expression, suggesting that CAF-mediated cell proliferation was also dependent on c-Myc expression. Subcutaneous tumor xenograft model showed that EC cells grew at least 1.4 times larger when co-injected with CAF, when compared to those injected with EC cells alone. Mice injected with EC cells with down-regulated c-Myc expression, however, showed at least 2.5 times smaller tumor compared to those in control group. Notably, there was no increase of tumor size when co-injected with CAFs

  10. Keeping the senescence secretome under control: Molecular reins on the senescence-associated secretory phenotype.

    Science.gov (United States)

    Malaquin, Nicolas; Martinez, Aurélie; Rodier, Francis

    2016-09-01

    Cellular senescence is historically associated with cancer suppression and aging. Recently, the reach of the senescence genetic program has been extended to include the ability of senescent cells to actively participate in tissue remodelling during many physiological processes, including placental biology, embryonic patterning, wound healing, and tissue stress responses caused by cancer therapy. Besides growth arrest, a significant feature of senescent cells is their ability to modify their immediate microenvironment using a senescence-associated (SA) secretome, commonly termed the SA secretory phenotype (SASP). Among others, the SASP contains growth factors, cytokines, and extracellular proteases that modulate the majority of both the beneficial and detrimental microenvironmental phenotypes caused by senescent cells. The SASP is thus becoming an obvious pharmaceutical target to manipulate SA effects. Herein, we review known signalling pathways underlying the SASP, including the DNA damage response (DDR), stress kinases, inflammasome, alarmin, inflammation- and cell survival-related transcription factors, miRNAs, RNA stability, autophagy, chromatin components, and metabolic regulators. We also describe the SASP as a temporally regulated dynamic sub-program of senescence that can be divided into a rapid DDR-associated phase, an early self-amplification phase, and a late "mature" phase, the late phase currently being the most widely studied SASP signature. Finally, we discuss how deciphering the signalling pathways regulating the SASP reveal targets that can be manipulated to harness the SA effects to benefit therapies for cancer and other age-related pathologies. PMID:27235851

  11. Inonotus obliquus Protects against Oxidative Stress-Induced Apoptosis and Premature Senescence

    OpenAIRE

    Yun, Jong Seok; Pahk, Jung Woon; Lee, Jong Seok; Shin, Won Cheol; Lee, Shin Young; Hong, Eock Kee

    2011-01-01

    In this study, we investigated the cytoprotective effects of Inonotus obliquus against oxidative stress-induced apoptosis and premature senescence. Pretreatment with I. obliquus scavenged intracellular ROS and prevented lipid peroxidation in hydrogen peroxide-treated human fibroblasts. As a result, I. obliquus exerted protective effects against hydrogen peroxide-induced apoptosis and premature senescence in human fibroblasts. In addition, I. obliquus suppressed UV-induced morphologic skin cha...

  12. Fibroblast growth factor receptor 4 Gly388Arg polymorphism in Chinese gastric cancer patients

    Directory of Open Access Journals (Sweden)

    Yan-Ying Shen

    2013-01-01

    Full Text Available AIM: To investigate the contribution of the fibroblast growth factor receptor 4 (FGFR4 Gly388Arg polymorphism as a genetic risk factor for gastric cancer (GC and to investigate any associations between this polymorphism and clinicopathological parameters and survival. METHODS: Tumors and matched adjacent non-cancer tissues were collected from 304 GC patients, and 5 mL of venous blood was collected from 62 GC patients and 392 age- and sex-matched healthy controls without cancer history from the same ethnic population. DNA was extracted, and direct sequencing analyses were performed to genotype the FGFR4 Gly388Arg polymorphism in all the samples. Differences in the genotype frequencies of the FGFR4 Gly388Arg polymorphism between GC patients and healthy controls were estimated using the χ2 test. Binary logistic regression was used for all analysis variables to estimate risk as the ORs with 95%CIs. The relationships between the FGFR4 genotype and clinicopathological parameters were tested with the χ2 test. The Kaplan-Meier product-limit method, the log-rank test, and the Cox regression model were applied to evaluate the effect of the FGFR4 genotype on the overall survival of patients with GC. RESULTS: In the present GC cohort, 118 patients (38.8% were homozygous for the Gly388 allele, 124 patients (40.8% were heterozygous, and 62 patients (20.4% were homozygous for the Arg388 allele. The frequencies of the Gly/Gly, Gly/Arg, and Arg/Arg genotypes in the healthy controls were 33.6%, 48.0%, and 18.4%, respectively. The distributions of genotypes (χ2 = 3.589, P = 0.166 and alleles (χ2 = 0.342, P = 0.559 of the FGFR4 Gly388Arg polymorphism were not different between the GC patients and the healthy controls. Although we observed no correlation between the FGFR4 Gly388Arg polymorphism and clinicopathological parameters or survival in the total cohort of GC patients, the presence of the Arg388 allele was associated with shorter survival time in patients

  13. NOTCH3 Is Induced in Cancer-Associated Fibroblasts and Promotes Angiogenesis in Oral Squamous Cell Carcinoma

    Science.gov (United States)

    Kayamori, Kou; Katsube, Ken-ichi; Sakamoto, Kei; Ohyama, Yoshio; Hirai, Hideaki; Yukimori, Akane; Ohata, Yae; Akashi, Takumi; Saitoh, Masao; Harada, Kiyoshi; Harada, Hiroyuki; Yamaguchi, Akira

    2016-01-01

    Recent studies have shown that Notch signaling is involved in many types of cancers, including oral squamous cell carcinomas (OSCCs). However, the role of Notch signaling in the tumor microenvironment is not yet fully understood. In this study, we investigated the roles of NOTCH3 signaling in cancer associated fibroblasts (CAFs) in OSCCs. Immunohistochemical study of 93 human tongue OSCC cases indicated that about one third of OSCCs showed NOTCH3 expression in CAFs, and that this expression significantly correlated with tumor-size. In vitro study showed that OSCC cell lines, especially HO1-N-1 cells stimulated NOTCH3 expression in normal human dermal fibroblasts (NHDFs) through direct cell-to-cell contact. Immunohistochemical and morphometric analysis using human OSCC samples demonstrated that NOTCH3 expression in CAFs significantly correlated with micro-vessel density in cancer stroma. In vitro angiogenesis assays involving co-culture of NHDFs with HO1-N-1 and human umbilical endothelial cells (HUVECs), and NOTCH3 knockdown in NHDFs using siRNA, demonstrated that HO1-N-1 cells significantly promoted tube formation dependent on NOTCH3-expression in NHDFs. Moreover, NOTCH3 expression in CAFs was related to poor prognosis of the OSCC patients. This work provides a new insight into the role of Notch signaling in CAFs associated with tumor angiogenesis and the possibility of NOTCH3-targeted molecular therapy in OSCCs. PMID:27124156

  14. TGF-β/NF1/Smad4-mediated suppression of ANT2 contributes to oxidative stress in cellular senescence.

    Science.gov (United States)

    Kretova, Miroslava; Sabova, Ludmila; Hodny, Zdenek; Bartek, Jiri; Kollarovic, Gabriel; Nelson, Buck D; Hubackova, Sona; Luciakova, Katarina

    2014-12-01

    Oxidative stress and persistent activation of DNA damage response (DDR) are causally involved in the development of cellular senescence, a phenomenon implicated in fundamental (patho)physiological processes such as aging, fetal development and tumorigenesis. Here, we report that adenine nucleotide translocase-2 (ANT2) is consistently down-regulated in all three major forms of cellular senescence: replicative, oncogene-induced and drug-induced, in both normal and cancerous human cells. We previously reported formation of novel NF1/Smad transcription repressor complexes in growth-arrested fibroblasts. Here we show that such complexes form in senescent cells. Mechanistically, binding of the NF1/Smad complexes to the NF1-dependent repressor elements in the ANT2 gene promoter repressed ANT2 expression. Etoposide-induced formation of these complexes and repression of ANT2 were relatively late events co-incident with production and secretion of, and dependent on, TGF-β. siRNA-mediated knock-down of ANT2 in proliferating cells resulted in increased levels of reactive oxygen species (ROS) and activation of the DDR. Knock-down of ANT2, together with etoposide treatment, further intensified ROS production and DNA damage signaling, leading to enhanced apoptosis. Together, our data show that TGF-β-mediated suppression of ANT2 through NF1/Smad4 complexes contributes to oxidative stress and DNA damage during induction of cellular senescence. PMID:25220407

  15. Cancer-associated fibroblasts promote hepatocellular carcinoma metastasis through chemokine-activated hedgehog and TGF-β pathways.

    Science.gov (United States)

    Liu, Jiao; Chen, Sheng; Wang, Wei; Ning, Bei-Fang; Chen, Fei; Shen, Weifeng; Ding, Jin; Chen, Wansheng; Xie, Wei-Fen; Zhang, Xin

    2016-08-28

    Fibroblasts are rich in the surrounding microenvironment of hepatocellular carcinoma (HCC) because most HCCs occur in fibrotic or cirrhotic livers. However, the role of cancer-associated fibroblasts (CAFs) in HCC metastasis remains obscure. Here, we reported that CAFs promote the migration and invasion of HCC cells in vitro and facilitate the HCC metastasis to the bone, brain and lung in NOD/SCID mice. The RayBio human chemokine antibody array revealed that CAFs secret higher levels of CCL2, CCL5, CCL7 and CXCL16 than peri-tumor fibroblasts. CCL2 and CCL5 increase the migration but not the invasion of HCC cells, while CCL7 and CXCL16 promote both migration and invasion of HCC cells. Moreover, CCL2 and CCL5 stimulate the activation of the hedgehog (Hh) pathway, while CCL7 and CXCL16 enhance the activity of the transforming growth factor-β (TGF-β) pathway in HCC cells. The neutralizing antibodies of chemokines notably attenuate the effect of CAFs on HCC metastasis and compromised the activation of Hh and TGF-β pathways in HCC cells. In summary, CAF-secreted CCL2, CCL5, CCL7 and CXCL16 promote HCC metastasis through the coordinate activation of Hh and TGF-β pathways in HCC cells. PMID:27216982

  16. Cell Surface Glycoprotein of Reactive Stromal Fibroblasts as a Potential Antibody Target in Human Epithelial Cancers

    Science.gov (United States)

    Garin-Chesa, Pilar; Old, Lloyd J.; Rettig, Wolfgang J.

    1990-09-01

    The F19 antigen is a cell surface glycoprotein (M_r, 95,000) of human sarcomas and proliferating, cultured fibroblasts that is absent from resting fibroblasts in normal adult tissues. Normal and malignant epithelial cells are also F19^-. The present immunohistochemical study describes induction of F19 in the reactive mesenchyme of epithelial tumors. F19^+ fibroblasts were found in primary and metastatic carcinomas, including colorectal (18 of 18 cases studied), breast (14/14), ovarian (21/21), bladder (9/10), and lung carcinomas (13/13). In contrast, the stroma of benign colorectal adenomas, fibrocystic disease and fibroadenomas of breast, benign prostate hyperplasia, in situ bladder carcinomas, and benign ovarian tumors showed no or only moderate numbers of F19^+ fibroblasts. Analysis of dermal incision wounds revealed that F19 is strongly induced during scar formation. Comparison of F19 with the extracellular matrix protein tenascin, a putative marker of tumor mesenchyme, showed a cellular staining pattern for F19 vs. the extracellular matrix pattern for tenascin and widespread expression of tenascin in F19^- normal tissues and benign tumors. Our results suggest that the F19^+ phenotype correlates with specialized fibroblast functions in wound healing and malignant tumor growth. Because of its abundance in tumor mesenchyme, F19 may serve as a target for antibodies labeled with radioisotopes or toxic agents, or inflammatogenic antibodies, in carcinoma patients.

  17. Hematopoietic stem cell-derived cancer-associated fibroblasts are novel contributors to the pro-tumorigenic microenvironment.

    Science.gov (United States)

    McDonald, Lindsay T; Russell, Dayvia L; Kelly, Ryan R; Xiong, Ying; Motamarry, Anjan; Patel, Risha K; Jones, Jeffrey A; Watson, Patricia M; Turner, David P; Watson, Dennis K; Soloff, Adam C; Findlay, Victoria J; LaRue, Amanda C

    2015-05-01

    Targeting the tumor microenvironment is critical toward improving the effectiveness of cancer therapeutics. Cancer-associated fibroblasts (CAFs) are one of the most abundant cell types of the tumor microenvironment, playing an important role in tumor progression. Multiple origins for CAFs have been proposed including resident fibroblasts, adipocytes, and bone marrow. Our laboratory previously identified a novel hematopoietic stem cell (HSC) origin for CAFs; however, the functional roles of HSC-derived CAFs (HSC-CAFs) in tumor progression have not yet been examined. To test the hypothesis that HSC-CAFs promote tumor progression through contribution to extracellular matrix (ECM) and paracrine production of pro-angiogenic factors, we developed a method to isolate HSC-CAFs. HSC-CAFs were profiled on the basis of their expression of hematopoietic and fibroblastic markers in two murine tumor models. Profiling revealed production of factors associated with ECM deposition and remodeling. Functional in vivo studies showed that co-injection of HSC-CAFs with tumor cells resulted in increased tumor growth rate and significantly larger tumors than tumor cells alone. Immunohistochemical studies revealed increased blood vessel density with co-injection, demonstrating a role for HSC-CAFs in tumor vascularization. Mechanistic in vitro studies indicated that HSC-CAFs play a role in producing vascular endothelial growth factor A and transforming growth factor-β1 in endothelial tube formation and patterning. In vitro and in vivo findings suggest that HSC-CAFs are a critical component of the tumor microenvironment and suggest that targeting the novel HSC-CAF may be a promising therapeutic strategy. PMID:26025666

  18. FAP-overexpressing fibroblasts produce an extracellular matrix that enhances invasive velocity and directionality of pancreatic cancer cells

    International Nuclear Information System (INIS)

    Alterations towards a permissive stromal microenvironment provide important cues for tumor growth, invasion, and metastasis. In this study, Fibroblast activation protein (FAP), a serine protease selectively produced by tumor-associated fibroblasts in over 90% of epithelial tumors, was used as a platform for studying tumor-stromal interactions. We tested the hypothesis that FAP enzymatic activity locally modifies stromal ECM (extracellular matrix) components thus facilitating the formation of a permissive microenvironment promoting tumor invasion in human pancreatic cancer. We generated a tetracycline-inducible FAP overexpressing fibroblastic cell line to synthesize an in vivo-like 3-dimensional (3D) matrix system which was utilized as a stromal landscape for studying matrix-induced cancer cell behaviors. A FAP-dependent topographical and compositional alteration of the ECM was characterized by measuring the relative orientation angles of fibronectin fibers and by Western blot analyses. The role of FAP in the matrix-induced permissive tumor behavior was assessed in Panc-1 cells in assorted matrices by time-lapse acquisition assays. Also, FAP+ matrix-induced regulatory molecules in cancer cells were determined by Western blot analyses. We observed that FAP remodels the ECM through modulating protein levels, as well as through increasing levels of fibronectin and collagen fiber organization. FAP-dependent architectural/compositional alterations of the ECM promote tumor invasion along characteristic parallel fiber orientations, as demonstrated by enhanced directionality and velocity of pancreatic cancer cells on FAP+ matrices. This phenotype can be reversed by inhibition of FAP enzymatic activity during matrix production resulting in the disorganization of the ECM and impeded tumor invasion. We also report that the FAP+ matrix-induced tumor invasion phenotype is β1-integrin/FAK mediated. Cancer cell invasiveness can be affected by alterations in the tumor

  19. In vitro radiosensitivity of primary human fibroblasts. Lack of correlation with acute radiation toxicity in patients with head and neck cancer

    International Nuclear Information System (INIS)

    Background and purpose: There is a considerable hope among clinicians and radiobiologists to detect genetically radiosensitive patients prior to radiotherapy. A predictive assay would enable adjustment of the total irradiation dose to the individual at a constant risk of normal tissue complications. In this prospective study, the clonogenic survival assay for primary human fibroblasts to determine radiosensitivity in vitro was evaluated and then correlated with clinically observed acute radiation reactions. Materials and methods: One hundred twenty-five independent survival experiments with primary fibroblasts derived from 63 biopsies from 55 cancer and non-cancer patients were performed. Results: A wide variation of cell survival between biopsies was detected. Statistical analysis revealed a highly significantly larger interindividual than intraindividual variation of SF2 values. However, a considerable scatter of SF2 values in repeated experiments was observed in individual cases. Age, gender, disease status (cancer patient, non-cancer patient) and origin of fibroblasts (skin, periodontal tissue) were demonstrated not to be statistically significant confounding factors on the intrinsic radiosensitivity in vitro. In a prospective study, no correlation of the SF2 and acute reactions in 25 patients with head and neck cancer treated with a primary accelerated radiochemotherapy was detected. Conclusion: Our data show that the clonogenic assay is able to distinguish between intrinsic radiosensitivities of primary human fibroblasts if a statistical approach is used but does not predict acute radiation toxicity

  20. Human mammary fibroblasts stimulate invasion of breast cancer cells in a three-dimensional culture and increase stroma development in mouse xenografts

    International Nuclear Information System (INIS)

    Tumour phenotype is regulated in a complex fashion as a result of interactions between malignant cells and the tumour stroma. Fibroblasts are the most abundant and perhaps most active part of the tumour stroma. A better understanding of the changes that occur in fibroblasts in response to the presence of malignant cells may lead to the development of new strategies for cancer treatment. We explored the effects of fibroblasts on the growth and invasion of mammary carcinoma tumour cells in vitro and in vivo. In order to analyse secreted factors that affect invasive abilities of breast cancer cells we co-cultured human mammary fibroblasts (HMF3s) and cancer cells (MCF7S1) in three-dimensional (3D) growth conditions devoid of heterogeneous cell-cell contact. To study the possible influence of fibroblasts on MCF7S1 cancer cell growth in vivo we co-injected HMF3s and MCF7S1 cells in Balb/c nu/nu mice. In 3D co-culture both HMF3s and MCF7S1 cells demonstrated enhanced invasion into a Matrigel matrix. This was correlated with enhanced expression of the metastasis promoting S100A4 protein in fibroblasts, stimulation of the matrix metalloproteinase (MMP)-2 activity, and enhanced secretion of a range of different cytokines. Orthotopic injection of oestrogen-dependent MCF7S1 cancer cells together with fibroblasts showed stimulation of tumour growth in mice without an external oestrogen supply. The resulting tumours were characterized by increased development of extracellular matrix, as well as an increase of murine S100A4 concentration and activity of MMP-2 in the tumour interstitial fluid. Stimulation of the invasive phenotype of tumour cells in 3D co-cultures with fibroblasts could be correlated with increased production of S100A4 and MMP-2. We propose that enhanced development of mouse host-derived tumour stroma in a MCF7S1 co-injection xenograft model leads to oestrogen independency and is triggered by the initial presence of human fibroblasts

  1. Senescence Meets Dedifferentiation

    Directory of Open Access Journals (Sweden)

    Yemima Givaty Rapp

    2015-06-01

    Full Text Available Senescence represents the final stage of leaf development but is often induced prematurely following exposure to biotic and abiotic stresses. Leaf senescence is manifested by color change from green to yellow (due to chlorophyll degradation or to red (due to de novo synthesis of anthocyanins coupled with chlorophyll degradation and frequently culminates in programmed death of leaves. However, the breakdown of chlorophyll and macromolecules such as proteins and RNAs that occurs during leaf senescence does not necessarily represent a one-way road to death but rather a reversible process whereby senescing leaves can, under certain conditions, re-green and regain their photosynthetic capacity. This phenomenon essentially distinguishes senescence from programmed cell death, leading researchers to hypothesize that changes occurring during senescence might represent a process of trans-differentiation, that is the conversion of one cell type to another. In this review, we highlight attributes common to senescence and dedifferentiation including chromatin structure and activation of transposable elements and provide further support to the notion that senescence is not merely a deterioration process leading to death but rather a unique developmental state resembling dedifferentiation.

  2. PML, SUMOylation and senescence

    Directory of Open Access Journals (Sweden)

    HuguesDe Thé

    2013-07-01

    Full Text Available Since its discovery, 25 years ago, PML has been an enigma. Implicated in the oncogenic PML/RARA fusion, forming elusive intranuclear domains, triggering cell death or senescence, controlled by and perhaps controlling SUMOylation... there are multiple PML-related issues. Here we review the reciprocal interactions between PML, senescence and SUMOylation, notably in the context of cellular transformation.

  3. Evolution of plant senescence

    Directory of Open Access Journals (Sweden)

    Young Mike

    2009-07-01

    Full Text Available Abstract Background Senescence is integral to the flowering plant life-cycle. Senescence-like processes occur also in non-angiosperm land plants, algae and photosynthetic prokaryotes. Increasing numbers of genes have been assigned functions in the regulation and execution of angiosperm senescence. At the same time there has been a large expansion in the number and taxonomic spread of plant sequences in the genome databases. The present paper uses these resources to make a study of the evolutionary origins of angiosperm senescence based on a survey of the distribution, across plant and microbial taxa, and expression of senescence-related genes. Results Phylogeny analyses were carried out on protein sequences corresponding to genes with demonstrated functions in angiosperm senescence. They include proteins involved in chlorophyll catabolism and its control, homeoprotein transcription factors, metabolite transporters, enzymes and regulators of carotenoid metabolism and of anthocyanin biosynthesis. Evolutionary timelines for the origins and functions of particular genes were inferred from the taxonomic distribution of sequences homologous to those of angiosperm senescence-related proteins. Turnover of the light energy transduction apparatus is the most ancient element in the senescence syndrome. By contrast, the association of phenylpropanoid metabolism with senescence, and integration of senescence with development and adaptation mediated by transcription factors, are relatively recent innovations of land plants. An extended range of senescence-related genes of Arabidopsis was profiled for coexpression patterns and developmental relationships and revealed a clear carotenoid metabolism grouping, coordinated expression of genes for anthocyanin and flavonoid enzymes and regulators and a cluster pattern of genes for chlorophyll catabolism consistent with functional and evolutionary features of the pathway. Conclusion The expression and phylogenetic

  4. Essential roles of the interaction between cancer cell-derived chemokine, CCL4, and intra-bone CCR5-expressing fibroblasts in breast cancer bone metastasis

    OpenAIRE

    Sasaki, Soichiro; Baba, Tomohisa; Nishimura, Tatsunori; Hayakawa, Yoshihiro; Hashimoto, Shin-ichi; GOTO, Noriko(Graduate school of Education,Tokyo Gakugei University); Mukaida, Naofumi

    2016-01-01

    From a murine breast cancer cell line, 4T1, we established a subclone, 4T1.3, which consistently metastasizes to bone upon its injection into the mammary fat pad. 4T1.3 clone exhibited similar proliferation rate and migration capacity as the parental clone. However, the intra-bone injection of 4T1.3 clone caused larger tumors than that of the parental cells, accompanied with increases in fibroblast, but not osteoclast or osteoblast numbers. 4T1.3 clone displayed an enhanced expression of a ch...

  5. N-Methyl-N'-nitro-N-nitrosoguanidine-induced senescence-like growth arrest in colon cancer cells is associated with loss of adenomatous polyposis coli protein, microtubule organization, and telomeric DNA

    Directory of Open Access Journals (Sweden)

    Narayan Satya

    2004-01-01

    Full Text Available Abstract Background Cellular senescence is a state in which mammalian cells enter into an irreversible growth arrest and altered biological functions. The senescence response in mammalian cells can be elicited by DNA-damaging agents. In the present study we report that the DNA-damaging agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG is able to induce senescence in the HCT-116 colon cancer cell line. Results Cells treated with lower concentrations of MNNG (0–25 microM for 50 h showed a dose-dependent increase in G2/M phase arrest and apoptosis; however, cells treated with higher concentrations of MNNG (50–100 microM showed a senescence-like G0/G1 phase arrest which was confirmed by increased expression of β-galactosidase, a senescence induced marker. The G2/M phase arrest and apoptosis were found to be associated with increased levels of p53 protein, but the senescence-like G0/G1 phase arrest was dissociated with p53 protein levels, since the p53 protein levels decreased in senescence-like arrested cells. We further, determined whether the decreased level of p53 was a transcriptional or a translational phenomenon. The results revealed that the decreased level of p53 protein in senescence-like arrested cells was a transcriptional phenomenon since p53 mRNA levels simultaneously decreased after treatment with higher concentrations of MNNG. We also examined the effect of MNNG treatment on other cell cycle-related proteins such as p21, p27, cyclin B1, Cdc2, c-Myc and max. The expression levels of these proteins were increased in cells treated with lower concentrations of MNNG, which supported the G2/M phase arrest. However, cells treated with higher concentrations of MNNG showed decreased levels of these proteins, and hence, may not play a role in cell cycle arrest. We then examined a possible association of the expression of APC protein and telomeric DNA signals with cellular senescence in MNNG-treated cells. We found that protein and m

  6. Overview of Space Radiation Health Risks (Cancer, Cognition, Cardiovascular) and Potential Common Pathways Such as Senescence and Inflammation

    Science.gov (United States)

    Patel, Zarana S.; Huff, Janice L.; Simonsen, Lisa C.

    2016-01-01

    The radiation environment in space poses significant challenges to human health and is a major concern for long duration, manned space missions. Outside the Earth's protective magnetosphere, astronauts are exposed to higher levels of galactic cosmic rays, whose physical characteristics are distinct from terrestrial sources of radiation such as x-rays and gamma-rays. Galactic cosmic rays consist of high energy, high charge (HZE) particles as well as high energy protons; they impart unique biological damage as they traverse through tissue with impacts on human health that are largely unknown. Understanding the quantitative and qualitative differences in biological responses produced by galactic cosmic radiation compared to Earth-based radiation is a major focus of space radiation research and is imperative for accurate risk assessment for long duration space missions. The major health issues of concern are epithelial carcinogenesis, central nervous system effects that may result in acute (inflight) cognitive impairment and late neurological disorders, degenerative tissue effects including cardiovascular, digestive and respiratory risks as well as possible acute radiation syndromes in the event of an unshielded exposure to a large solar particle event. In this presentation, we review evidence for health risks associated with heavy ion exposure and research strategies to enable manned space flight outside low Earth orbit. We are currently focused on common risk pathways that can be targeted for mitigation via countermeasures, and senescence and inflammation are prime areas for investigation.

  7. The small-molecule Bcl-2 inhibitor HA14-1 sensitizes cervical cancer cells, but not normal fibroblasts, to heavy-ion radiation

    International Nuclear Information System (INIS)

    This is the first study to demonstrate that the small-molecule Bcl-2 inhibitor HA14-1 renders human cervical cancer cells and their Bcl-2 overexpressing radioresistant counterparts, but not normal fibroblasts, more susceptible to heavy ions. Thus, Bcl-2 may be an attractive target for improving the efficacy of heavy-ion therapy

  8. mda-7/IL-24: Multifunctional cancer-specific apoptosis-inducing cytokine

    OpenAIRE

    Gupta, Pankaj; Su, Zao-zhong; Lebedeva, Irina V.; Sarkar, Devanand; Sauane, Moira; Emdad, Luni; Michael A. Bachelor; Grant, Steven; Curiel, David T; Dent, Paul; Fisher, Paul B.

    2006-01-01

    “Differentiation therapy” provides a unique and potentially effective, less toxic treatment paradigm for cancer. Moreover, combining “differentiation therapy” with molecular approaches presents an unparalleled opportunity to identify and clone genes mediating cancer growth control, differentiation, senescence, and programmed cell death (apoptosis). Subtraction hybridization applied to human melanoma cells induced to terminally differentiate by treatment with fibroblast interferon (IFN-β) plus...

  9. Using real-time impedance-based assays to monitor the effects of fibroblast-derived media on the adhesion, proliferation, migration and invasion of colon cancer cells

    OpenAIRE

    2014-01-01

    Increasing our knowledge of the mechanisms regulating cell proliferation, migration and invasion are central to understanding tumour progression and metastasis. The local tumour microenvironment contributes to the transformed phenotype in cancer by providing specific environmental cues that alter the cells behaviour and promotes metastasis. Fibroblasts have a strong association with cancer and in recent times there has been some emphasis in designing novel therapeutic strategies that alter fi...

  10. The fibroblast Tiam1-osteopontin pathway modulates breast cancer invasion and metastasis

    OpenAIRE

    Xu, Kun; Tian, Xuejun; Oh, Sun Y.; Movassaghi, Mohammad; Naber, Stephen P.; Kuperwasser, Charlotte; Buchsbaum, Rachel J

    2016-01-01

    Background The tumor microenvironment has complex effects in cancer pathophysiology that are not fully understood. Most cancer therapies are directed against malignant cells specifically, leaving pro-malignant signals from the microenvironment unaddressed. Defining specific mechanisms by which the tumor microenvironment contributes to breast cancer metastasis may lead to new therapeutic approaches against advanced breast cancer. Methods We use a novel method for manipulating three-dimensional...

  11. A correlation between residual DNA double-strand breaks and clonogenic measurements of radiosensitivity in fibroblasts from preradiotherapy cervix cancer patients

    International Nuclear Information System (INIS)

    Purpose: To study the relationship between residual DNA damage and clonogenic measurements of radiosensitivity in fibroblasts from pretreatment cervix cancer patients. Methods and Materials: Early passage vaginal fibroblasts from nine preradiotherapy cervix cancer patients and two radiosensitive skin fibroblast cell strains were studied. Cell survival was measured by clonogenic assay following both high and low dose rate irradiation. Residual DNA damage was measured using pulsed-field gel electrophoresis (PFGE) after irradiating radiolabeled, plateau-phase cells at 37 deg. C and allowing 24 h for repair. DNA damage was expressed both in terms of the residual damage slope (fitted to data from 60 to 150 Gy) and the fraction of activity released (FAR) following 150 Gy. Results: The surviving fraction at 2 Gy (SF2) values after high dose rate irradiation for the vaginal fibroblasts ranged from 0.15 to 0.32 (a 2.2-fold difference). When the two radiosensitive cell strains were included, residual damage, expressed as the residual damage slope, correlated with α (r = 0.82, p = 0.002), D bar (r = -0.91, p 2 (p = -0.79, p = 0.004), and when the vaginal fibroblasts alone were studied, the residual damage slope again correlated with clonogenic survival, although less strongly [α (r 0.66, p = 0.053), D bar (r = -0.83, p = 0.006), and SF2 (r = -0.63, p 0.07)]. Within the group of vaginal fibroblasts there was a 4.0-fold difference in residual DNA damage slope. When residual damage was expressed as FAR at 150Gy, then for all cell strains the correlations were α: r 0.78, p 0.004, D bar: r = -0.86, p = 0.001, and SF2: r = -0.78, p = 0.004, and for the vaginal fibroblast strains alone the correlations were α: r = 0.60, p = 0.088, D bar: r = -0.75, p = 0.02, and SF2: r = 0.62, p = 0.077. Conclusion: This study confirms previous findings that residual DNA damage correlates with clonogenic survival in fibroblasts. In addition, it demonstrates a correlation for fibroblasts from

  12. Inhibition of the phosphoinositide 3-kinase pathway induces a senescence-like arrest mediated by p27Kip1

    NARCIS (Netherlands)

    Collado, M.; Medema, R.H.; Garcia-Cao, I.; Dubuisson, M.L.N.; Barradas, M.; Glassford, J.; Rivas, C.; Burgering, B.M.T.; Serrano, M.; Lam, E.W.-F.

    2000-01-01

    A senescence-like growth arrest is induced in mouse primary embryo fibroblasts by inhibitors of phosphoinositide 3-kinase (PI3K). We observed that senescence-like growth arrest is correlated with an increase in p27Kip1 but that down-regulation of other cyclin-dependent kinase (CDK) inhibitors, inclu

  13. Advancement of Phenotype Transformation of Cancer-associated Fibroblasts: 
from Genetic Alterations to Epigenetic Modification

    Directory of Open Access Journals (Sweden)

    Dali CHEN

    2015-02-01

    Full Text Available In the field of human cancer research, even though the vast majority attentions were paid to tumor cells as “the seeds”, the roles of tumor microenvironments as “the soil” are gradually explored in recent years. As a dominant compartment of tumor microenvironments, cancer-associated fibroblasts (CAFs were discovered to correlated with tumorigenesis, tumor progression and prognosis. And the exploration of the mechanisms of CAF phenotype transformation would conducive to the further understand of the CAFs function in human cancers. As we known that CAFs have four main origins, including epithelial cells, endothelial cells, mesenchymal stem cells (MSCs and local mesenchymal cells. However, researchers found that all these origins finally conduct similiar phenotypes from intrinsic to extrinsic ones. Thus, what and how a mechanism can conduct the phenotype transformation of CAFs with different origins? Two viewpoints are proposed to try to answer the quetsion, involving genetic alterations and epigenetic modifications. This review will systematically summarize the advancement of mechanisms of CAF phenotype transformations in the aspect of genentic and epigenetic modifications.

  14. Cancer-Associated Fibroblasts Regulate Tumor-Initiating Cell Plasticity in Hepatocellular Carcinoma through c-Met/FRA1/HEY1 Signaling

    OpenAIRE

    Eunice Yuen Ting Lau; Jessica Lo; Bowie Yik Ling Cheng; Mark Kin Fai Ma; Joyce Man Fong Lee; Johnson Kai Yu Ng; Stella Chai; Chi Ho Lin; Suk Ying Tsang; Stephanie Ma; Irene Oi Lin Ng; Terence Kin Wah Lee

    2016-01-01

    Like normal stem cells, tumor-initiating cells (T-ICs) are regulated extrinsically within the tumor microenvironment. Because HCC develops primarily in the context of cirrhosis, in which there is an enrichment of activated fibroblasts, we hypothesized that cancer-associated fibroblasts (CAFs) would regulate liver T-ICs. We found that the presence of α-SMA(+) CAFs correlates with poor clinical outcome. CAF-derived HGF regulates liver T-ICs via activation of FRA1 in an Erk1,2-dependent manner. ...

  15. TSH overcomes Braf(V600E)-induced senescence to promote tumor progression via downregulation of p53 expression in papillary thyroid cancer.

    Science.gov (United States)

    Zou, M; Baitei, E Y; Al-Rijjal, R A; Parhar, R S; Al-Mohanna, F A; Kimura, S; Pritchard, C; Binessa, H A; Alzahrani, A S; Al-Khalaf, H H; Hawwari, A; Akhtar, M; Assiri, A M; Meyer, B F; Shi, Y

    2016-04-14

    The BRAF(V600E) mutation is found in approximately 40% of papillary thyroid cancers (PTC). Mice with thyroid-specific expression of Braf(V600E) (TPO-Braf(V600E)) develop PTC rapidly with high levels of serum thyroid-stimulating hormone (TSH). It is unclear to what extent the elevated TSH contributes to tumor progression. To investigate the progression of Braf(V600E)-induced PTC (BVE-PTC) under normal TSH, we transplanted BVE-PTC tumors subcutaneously into nude and TPO-Braf(WT) mice. Regression of the transplanted tumors was observed in both nude and TPO-Braf(WT) mice. They were surrounded by heavy lymphocyte infiltration and oncogene-induced senescence (OIS) was demonstrated by strong β-gal staining and absence of Ki-67 expression. In contrast, BVE-PTC transplants continued to grow when transplanted into TPO-Braf(V600E) mice. The expression of Trp53 was increased in tumor transplants undergoing OIS. Trp53 inactivation reversed OIS and enabled tumor transplants to grow in nude mice with characteristic cell morphology of anaplastic thyroid cancer (ATC). PTC-to-ATC transformation was also observed in primary BVE-PTC tumors. ATC cells derived from Trp53 knockout tumors had increased PI3K/AKT signaling and became resistant to Braf(V600E) inhibitor PLX4720, which could be overcome by combined treatment of PI3K inhibitor LY294002 and PLX4720. In conclusion, BVE-PTC progression could be contained via p53-dependent OIS and TSH is a major disruptor of this balance. Simultaneous targeting of both MAPK and PI3K/AKT pathways offer a better therapeutic outcome against ATC. The current study reinforces the importance of rigorous control of serum TSH in PTC patients. PMID:26477313

  16. Influence of low doses of radiation due to 222Rn on proliferation of fibroblasts and MCF-7 human breast cancer cells in vitro

    International Nuclear Information System (INIS)

    The aim of the present study is to analyze the effects of low doses of radiation due to radon (within the range present in the environment) in the proliferation of normal (fibroblasts) and tumoral (MCF-7 human breast cancer cells) mammalian cells. Both fibroblast and MCF-7 cells were incubated in culture media with different levels of radon (doses of 10-15,000 μGy), or non-radon (control). After incubation the number of cells per plate was measured with a hemocytometer. The dissolution of radon in the culture media decreased the proliferation of MCF-7 cells (not the fibroblasts). Within the range of doses used in this experiment, the lowest as well as the highest doses of radiation had the lowest antiproliferative effects. Intermediate doses strongly decreased the number of final cells with respect to those in the control population

  17. Defective DNA repair increases susceptibility to senescence through extension of Chk1-mediated G2 checkpoint activation.

    Science.gov (United States)

    Johmura, Yoshikazu; Yamashita, Emiri; Shimada, Midori; Nakanishi, Keiko; Nakanishi, Makoto

    2016-01-01

    Susceptibility to senescence caused by defective DNA repair is a major hallmark of progeroid syndrome patients, but molecular mechanisms of how defective DNA repair predisposes to senescence are largely unknown. We demonstrate here that suppression of DNA repair pathways extends the duration of Chk1-dependent G2 checkpoint activation and sensitizes cells to senescence through enhancement of mitosis skipping. Extension of G2 checkpoint activation by introduction of the TopBP1 activation domain and the nondegradable mutant of Claspin sensitizes cells to senescence. In contrast, a shortening of G2 checkpoint activation by expression of SIRT6 or depletion of OTUB2 reduces susceptibility to senescence. Fibroblasts from progeroid syndromes tested shows a correlation between an extension of G2 checkpoint activation and an increase in the susceptibility to senescence. These results suggest that extension of G2 checkpoint activation caused by defective DNA repair is critical for senescence predisposition in progeroid syndrome patients. PMID:27507734

  18. Senescence and immortality in hepatocellular carcinoma.

    Science.gov (United States)

    Ozturk, Mehmet; Arslan-Ergul, Ayca; Bagislar, Sevgi; Senturk, Serif; Yuzugullu, Haluk

    2009-12-01

    Cellular senescence is a process leading to terminal growth arrest with characteristic morphological features. This process is mediated by telomere-dependent, oncogene-induced and ROS-induced pathways, but persistent DNA damage is the most common cause. Senescence arrest is mediated by p16(INK4a)- and p21(Cip1)-dependent pathways both leading to retinoblastoma protein (pRb) activation. p53 plays a relay role between DNA damage sensing and p21(Cip1) activation. pRb arrests the cell cycle by recruiting proliferation genes to facultative heterochromatin for permanent silencing. Replicative senescence that occurs in hepatocytes in culture and in liver cirrhosis is associated with lack of telomerase activity and results in telomere shortening. Hepatocellular carcinoma (HCC) cells display inactivating mutations of p53 and epigenetic silencing of p16(INK4a). Moreover, they re-express telomerase reverse transcriptase required for telomere maintenance. Thus, senescence bypass and cellular immortality is likely to contribute significantly to HCC development. Oncogene-induced senescence in premalignant lesions and reversible immortality of cancer cells including HCC offer new potentials for tumor prevention and treatment. PMID:19070423

  19. Cross-species functional analysis of cancer-associated fibroblasts identifies a critical role for CLCF1 and IL6 in non-small cell lung cancer in vivo

    OpenAIRE

    Vicent, Silvestre; Sayles, Leanne C.; Vaka, Dedeepya; Khatri, Purvesh; Gevaert, Olivier; Chen, Ron; Zheng, Yanyan; Anna K Gillespie; Clarke, Nicole; Xu, Yue; Shrager, Joseph; Hoang, Chuong D.; Plevritis, Sylvia; Butte, Atul J; Sweet-Cordero, E. Alejandro

    2012-01-01

    Cancer-associated fibroblasts (CAFs) have been reported to support tumor progression by a variety of mechanisms. However, their role in the progression of non-small cell lung cancer (NSCLC) remains poorly defined. In addition, the extent to which specific proteins secreted by CAFs contribute directly to tumor growth is unclear. To study the role of CAFs in NSCLC, a cross-species functional characterization of mouse and human lung CAFs was performed. CAFs supported the growth of lung cancer ce...

  20. Histone Modifications in Senescence-Associated Resistance to Apoptosis by Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Yan Y. Sanders

    2013-01-01

    Full Text Available Aging and age-related diseases are associated with cellular senescence that results in variable apoptosis susceptibility to oxidative stress. Although fibroblast senescence has been associated with apoptosis resistance, mechanisms for this have not been well defined. In this report, we studied epigenetic mechanisms involving histone modifications that confer apoptosis resistance to senescent human diploid fibroblasts (HDFs. HDFs that undergo replicative senescence display typical morphological features, express senescence-associated β-galactosidase, and increased levels of the tumor suppressor genes, p16, p21, and caveolin-1. Senescent HDFs are more resistant to oxidative stress (exogenous H2O2-induced apoptosis in comparison to non-senescent (control HDFs; this is associated with constitutively high levels of the anti-apoptotic gene, Bcl-2, and low expression of the pro-apoptotic gene, Bax. Cellular senescence is characterized by global increases in H4K20 trimethylation and decreases in H4K16 acetylation in association with increased activity of Suv420h2 histone methyltransferase (which targets H4K20, decreased activity of the histone acetyltransferase, Mof (which targets H4K16, as well as decreased total histone acetyltransferase activity. In contrast to Bax gene, chromatin immunoprecipitation studies demonstrate marked enrichment of the Bcl-2 gene with H4K16Ac, and depletion with H4K20Me3, predicting active transcription of this gene in senescent HDFs. These data indicate that both global and locus-specific histone modifications of chromatin regulate altered Bcl-2:Bax gene expression in senescent fibroblasts, contributing to its apoptosis-resistant phenotype.

  1. Characterization of various cell lines from different ampullary cancer subtypes and cancer associated fibroblast-mediated responses

    OpenAIRE

    Lai, Zon Weng; Bolm, Louisa; Fuellgraf, Hannah; Biniossek, Martin L.; Makowiec, Frank; Hopt, Ulrich Theodor; Werner, Martin; Keck, Tobias; Bausch, Dirk; Sorio, Claudio; Scarpa, Aldo; Schilling, Oliver; Bronsert, Peter; Wellner, Ulrich Friedrich

    2016-01-01

    Background Ampullary cancer is a relatively rare form of cancer and usually treated by pancreatoduodenectomy, followed by adjuvant therapy. The intestinal subtype is associated with markedly improved prognosis after resection. At present, only few cell lines are available for in vitro studies of ampullary cancer and they have not been collectively characterized. Methods We characterize five ampullary cancer cell lines by subtype maker expression, epithelial-mesenchymal transition (EMT) featur...

  2. Low-Dose Hyper-Radiosensitivity Is Not a Common Effect in Normal Asynchronous and G2-Phase Fibroblasts of Cancer Patients

    International Nuclear Information System (INIS)

    Purpose: In our previous study, using the micronucleus assay, a low-dose hyper-radiosensitivity (HRS)-like phenomenon was observed for normal fibroblasts of 2 of the 40 cancer patients investigated. In this article we report, for the first time, the survival response of primary fibroblasts from 25 of these patients to low-dose irradiation and answer the question regarding the effect of G2-phase enrichment on HRS elicitation. Methods and Materials: The clonogenic survival of asynchronous as well as G2-phase enriched fibroblast populations was measured. Separation of G2-phase cells and precise cell counting was performed using a fluorescence-activated cell sorter. Sorted and plated cells were irradiated with single doses (0.1-4 Gy) of 6-MV x-rays. For each patient, at least 4 independent experiments were performed, and the induced-repair model was fitted over the whole data set to confirm the presence of HRS effect. Results: The HRS response was demonstrated for the asynchronous and G2-phase enriched cell populations of 4 patients. For the rest of patients, HRS was not defined in either of the 2 fibroblast populations. Thus, G2-phase enrichment had no effect on HRS elicitation. Conclusions: The fact that low-dose hyper-radiosensitivity is not a common effect in normal human fibroblasts implies that HRS may be of little consequence in late-responding connective tissues with regard to radiation fibrosis

  3. Vitamin E Supplementation Delays Cellular Senescence In Vitro.

    Science.gov (United States)

    La Fata, Giorgio; Seifert, Nicole; Weber, Peter; Mohajeri, M Hasan

    2015-01-01

    Vitamin E is an important antioxidant that protects cells from oxidative stress-induced damage, which is an important contributor to the progression of ageing. Ageing can be studied in vitro using primary cells reaching a state of irreversible growth arrest called senescence after a limited number of cellular divisions. Generally, the most utilized biomarker of senescence is represented by the expression of the senescence associated β-galactosidase (SA-β-gal). We aimed here to study the possible effects of vitamin E supplementation in two different human primary cell types (HUVECs and fibroblasts) during the progression of cellular senescence. Utilizing an unbiased automated system, based on the detection of the SA-β-gal, we quantified cellular senescence in vitro and showed that vitamin E supplementation reduced the numbers of senescent cells during progression of ageing. Acute vitamin E supplementation did not affect cellular proliferation, whereas it was decreased after chronic treatment. Mechanistically, we show that vitamin E supplementation acts through downregulation of the expression of the cycline dependent kinase inhibitor P21. The data obtained from this study support the antiageing properties of vitamin E and identify possible mechanisms of action that warrant further investigation. PMID:26613084

  4. Vitamin E Supplementation Delays Cellular Senescence In Vitro

    Directory of Open Access Journals (Sweden)

    Giorgio La Fata

    2015-01-01

    Full Text Available Vitamin E is an important antioxidant that protects cells from oxidative stress-induced damage, which is an important contributor to the progression of ageing. Ageing can be studied in vitro using primary cells reaching a state of irreversible growth arrest called senescence after a limited number of cellular divisions. Generally, the most utilized biomarker of senescence is represented by the expression of the senescence associated β-galactosidase (SA-β-gal. We aimed here to study the possible effects of vitamin E supplementation in two different human primary cell types (HUVECs and fibroblasts during the progression of cellular senescence. Utilizing an unbiased automated system, based on the detection of the SA-β-gal, we quantified cellular senescence in vitro and showed that vitamin E supplementation reduced the numbers of senescent cells during progression of ageing. Acute vitamin E supplementation did not affect cellular proliferation, whereas it was decreased after chronic treatment. Mechanistically, we show that vitamin E supplementation acts through downregulation of the expression of the cycline dependent kinase inhibitor P21. The data obtained from this study support the antiageing properties of vitamin E and identify possible mechanisms of action that warrant further investigation.

  5. Markers of fibroblast-rich tumor stroma and perivascular cells in serous ovarian cancer: Inter- and intra-patient heterogeneity and impact on survival

    Science.gov (United States)

    Corvigno, Sara; Wisman, G. Bea A.; Mezheyeuski, Artur; van der Zee, Ate G.J.; Nijman, Hans W.; Åvall-Lundqvist, Elisabeth; Östman, Arne; Dahlstrand, Hanna

    2016-01-01

    Inter- and intra-patient variations in tumor microenvironment of serous ovarian cancer are largely unexplored. We aimed to explore potential co-regulation of tumor stroma characteristics, analyze their concordance in primary and metastatic lesions, and study their impact on survival. A tissue microarray (TMA) with 186 tumors and 91 matched metastases was subjected to immunohistochemistry double staining with endothelial cell marker CD34 and fibroblast and pericyte markers α-SMA, PDGFβR and desmin. Images were digitally analyzed to yield “metrics” related to vasculature and stroma features. Intra-case analyses showed that PDGFβR in perivascular cells and fibroblasts were strongly correlated. Similar findings were observed concerning α-SMA. Most stroma characteristics showed large variations in intra-case comparisons of primary tumors and metastasis. Large PDGFβR-positive stroma fraction and high PDGFβFR positive perivascular intensity were both significantly associated with shorter survival in uni- and multi-variate analyses (HR 1.7, 95% CI 1.1-2.5; HR 1.7, 95% CI 1.1-2.8). In conclusion, we found PDGFβR- and α-SMA-expression to be largely independent of each other but concordantly activated in perivascular cells and in fibroblasts within the primary tumor. Stromal characteristics differed between primary tumors and metastases. PDGFβR in perivascular cells and in fibroblasts may be novel prognostic markers in serous ovarian cancer. PMID:26918345

  6. Fibroblast-Mediated Collagen Remodeling Within the Tumor Microenvironment Facilitates Progression of Thyroid Cancers Driven by BrafV600E and Pten Loss.

    Science.gov (United States)

    Jolly, Lee Ann; Novitskiy, Sergey; Owens, Phillip; Massoll, Nicole; Cheng, Nikki; Fang, Wei; Moses, Harold L; Franco, Aime T

    2016-04-01

    Contributions of the tumor microenvironment (TME) to progression in thyroid cancer are largely unexplored and may illuminate a basis for understanding rarer aggressive cases of this disease. In this study, we investigated the relationship between the TME and thyroid cancer progression in a mouse model where thyroid-specific expression of oncogenic BRAF and loss of Pten (Braf(V600E)/Pten(-/-)/TPO-Cre) leads to papillary thyroid cancers (PTC) that rapidly progress to poorly differentiated thyroid cancer (PDTC). We found that fibroblasts were recruited to the TME of Braf(V600E)/Pten(-/-)/TPO-Cre thyroid tumors. Conditioned media from cell lines established from these tumors, but not tumors driven by mutant H-ras, induced fibroblast migration and proliferation in vitro Notably, the extracellular matrix of Braf(V600E)/Pten(-/-)/TPO-Cre tumors was enriched with stromal-derived fibrillar collagen, compared with wild-type or Hras-driven tumors. Further, type I collagen enhanced the motility of Braf(V600E)/Pten(-/-)/TPO-Cre tumor cells in vitro In clinical specimens, we found COL1A1 and LOX to be upregulated in PTC and expressed at highest levels in PDTC and anaplastic thyroid cancer. Additionally, increased expression levels of COL1A1 and LOX were associated with decreased survival in thyroid cancer patients. Overall, our results identified fibroblast recruitment and remodeling of the extracellular matrix as pivotal features of the TME in promoting thyroid cancer progression, illuminating candidate therapeutic targets and biomarkers in advanced forms of this malignancy. Cancer Res; 76(7); 1804-13. ©2016 AACR. PMID:26818109

  7. Human Subperitoneal Fibroblast and Cancer Cell Interaction Creates Microenvironment That Enhances Tumor Progression and Metastasis

    OpenAIRE

    Kojima, Motohiro; Higuchi, Youichi; Yokota, Mitsuru; Ishii, Genichiro; Saito, Norio; Aoyagi, Kazuhiko; Sasaki, Hiroki; Ochiai, Atsushi

    2014-01-01

    Backgrounds Peritoneal invasion in colon cancer is an important prognostic factor. Peritoneal invasion can be objectively identified as periotoneal elastic laminal invasion (ELI) by using elastica stain, and the cancer microenvironment formed by the peritoneal invasion (CMPI) can also be observed. Cases with ELI more frequently show distant metastasis and recurrence. Therefore, CMPI may represent a particular milieu that facilitates tumor progression. Pathological and biological investigation...

  8. Cancer-Associated Fibroblasts from lung tumors maintain their immuno-suppressive abilities after high-dose irradiation

    Directory of Open Access Journals (Sweden)

    Laia eGorchs

    2015-05-01

    Full Text Available Accumulating evidence supports the notion that high-dose (>5 Gy radiotherapy (RT regimens are triggering stronger pro-immunogenic effects than standard low-dose (2 Gy regimens. However, the effects of RT on certain immunoregulatory elements in tumors remain unexplored. In this study we have investigated the effects of high-dose irradiation (HD-RT on the immunomodulating functions of cancer-associated fibroblasts (CAFs. Primary CAF cultures were established from lung cancer specimens derived from patients diagnosed for non-small cell lung cancer. Irradiated and non-irradiated CAFs were examined for immunomodulation in experiments with peripheral blood mononuclear cells from random, healthy donors. Regulation of lymphocytes behavior was checked by lymphocyte proliferation assays, lymphocyte migration assays and T-cell cytokine production. Additionally, CAF-secreted immuno-regulatory factors were studied by multiplex protein arrays, ELISAs and by LC-MS/MS proteomics. In all functional assays we observed a powerful immuno-suppressive effect exerted by CAF-conditioned medium on activated T-cells (p>0,001, and this effect was sustained after a single radiation dose of 18 Gy. Relevant immuno-suppressive molecules such as prostaglandin E2, interleukin-6 and -10, or transforming growth factor-β were found in CAF conditioned medium, but their secretion was unchanged after irradiation. Finally, immunogenic cell death responses in CAFs were studied by exploring the release of high motility group box-1 and ATP. Both alarmins remained undetectable before and after irradiation. In conclusion, CAFs play a powerful immuno-suppressive effect over activated T-cells, and this effect remains unchanged after HD-RT. Importantly, CAFs do not switch on immunogenic cell death responses after exposure to HD-RT.

  9. From Ancient Pathways to Aging Cells-Connecting Metabolism and Cellular Senescence.

    Science.gov (United States)

    Wiley, Christopher D; Campisi, Judith

    2016-06-14

    Cellular senescence is a complex stress response that permanently arrests the proliferation of cells at risk for oncogenic transformation. However, senescent cells can also drive phenotypes associated with aging. Although the senescence-associated growth arrest prevents the development of cancer, and the metabolism of cancer cells has been studied in depth, the metabolic causes and consequences of cellular senescence were largely unexplored until recently. New findings reveal key roles for several aspects of cellular metabolism in the establishment and control of senescent phenotypes. These discoveries have important implications for both cancer and aging. In this review, we highlight some of the recent links between metabolism and phenotypes that are commonly associated with senescent cells. PMID:27304503

  10. Inonotus obliquus protects against oxidative stress-induced apoptosis and premature senescence.

    Science.gov (United States)

    Yun, Jong Seok; Pahk, Jung Woon; Lee, Jong Seok; Shin, Won Cheol; Lee, Shin Young; Hong, Eock Kee

    2011-05-01

    In this study, we investigated the cytoprotective effects of Inonotus obliquus against oxidative stress-induced apoptosis and premature senescence. Pretreatment with I. obliquus scavenged intracellular ROS and prevented lipid peroxidation in hydrogen peroxide-treated human fibroblasts. As a result, I. obliquus exerted protective effects against hydrogen peroxide-induced apoptosis and premature senescence in human fibroblasts. In addition, I. obliquus suppressed UV-induced morphologic skin changes, such as skin thickening and wrinkle formation, in hairless mice in vivo and increased collagen synthesis through inhibition of MMP-1 and MMP-9 activities in hydrogen peroxide-treated human fibroblasts. Taken together, these results demonstrate that I. obliquus can prevent the aging process by attenuating oxidative stress in a model of stress-induced premature senescence. PMID:21359681

  11. Novel expression of CST1 as candidate senescence marker.

    Science.gov (United States)

    Keppler, Daniel; Zhang, Jun; Bihani, Teeru; Lin, Athena W

    2011-07-01

    Senescent cells exhibit altered expression of numerous genes. Identifying the significance of the changes in gene expression may help advance our understanding of the senescence biology. Here, we report on the consistent and strong upregulation of CST1 expression during cellular senescence, independent of the initial trigger. CST1 expression at both the messenger RNA and protein levels was barely detected in control cells, which included early passage proliferating, quiescent, or immortal human fibroblasts and various human tumor cell lines. Immunoblotting and immunofluorescence cytochemical studies further suggest that CST1 accumulates intracellularly, within vesicular structures. We discuss these results in light of the known function of CST1 as a potent inhibitor of lysosomal cysteine proteases. PMID:21636832

  12. Never-ageing cellular senescence

    OpenAIRE

    Ogrunc, Müge; d’Adda di Fagagna, Fabrizio

    2011-01-01

    Cellular senescence was historically discovered as a form of cellular ageing of in vitro cultured cells. It has been under the spotlight following the evidence of oncogene-induced senescence in vivo and its role as a potent tumour suppressor mechanism. Presently, a PubMed search using keywords ‘cellular senescence and cancer’ reveals 8398 number of references (by April 2011) showing that while our knowledge of senescence keeps expanding, the complexity of the phenomenon keeps us – researchers...

  13. Fibroblast growth factor signaling and inhibition in non-small cell lung cancer and their role in squamous cell tumors

    International Nuclear Information System (INIS)

    With the introduction of targeted agents primarily applicable to non-small cell lung cancer (NSCLC) of adenocarcinoma histology, there is a heightened unmet need in the squamous cell carcinoma population. Targeting the angiogenic fibroblast growth factor (FGF)/FGF receptor (FGFR) signaling pathway is among the strategies being explored in squamous NSCLC; these efforts are supported by growth-promoting effects of FGF signaling in preclinical studies (including interactions with other pathways) and observations suggesting that FGF/FGFR-related aberrations may be more common in squamous versus adenocarcinoma and other histologies. A number of different anti-FGF/FGFR approaches have shown promise in preclinical studies. Clinical trials of two multitargeted tyrosine kinase inhibitors are restricting enrollment to patients with squamous NSCLC: a phase I/II trial of nintedanib added to first-line gemcitabine/cisplatin and a phase II trial of ponatinib for previously treated advanced disease, with the latter requiring not only squamous disease but also a confirmed FGFR kinase amplification or mutation. There are several ongoing clinical trials of multitargeted agents in general NSCLC populations, including but not limited to patients with squamous disease. Other FGF/FGFR-targeted agents are in earlier clinical development. While results are awaited from these clinical investigations in squamous NSCLC and other disease settings, additional research is needed to elucidate the role of FGF/FGFR signaling in the biology of NSCLC of different histologies

  14. Glioma-associated endothelial cells show evidence of replicative senescence

    International Nuclear Information System (INIS)

    The innately programmed process of replicative senescence has been studied extensively with respect to cancer, but primarily from the perspective of tumor cells overcoming this stringent innate barrier and acquiring the capacity for unlimited proliferation. In this study, we focus on the potential role of replicative senescence affecting the non-transformed endothelial cells of the blood vessels within the tumor microenvironment. Based on the well-documented aberrant structural and functional features of blood vessels within solid tumors, we hypothesized that tumor-derived factors may lead to premature replicative senescence in tumor-associated brain endothelial cells (TuBEC). We show here that glioma tissue, but not normal brain tissue, contains cells that express the signature of replicative senescence, senescence-associated β-galactosidase (SA-β-gal), on CD31-positive endothelial cells. Primary cultures of human TuBEC stain for SA-β-gal and exhibit characteristics of replicative senescence, including increased levels of the cell cycle inhibitors p21 and p27, increased resistance to cytotoxic drugs, increased growth factor production, and inability to proliferate. These data provide the first demonstration that tumor-derived brain endothelial cells may have reached an end-stage of differentiation known as replicative senescence and underscore the need for anti-angiogenic therapies to target this unique tumor-associated endothelial cell population

  15. Genetic characterization of senescence-accelerated mouse (SAM).

    Science.gov (United States)

    Higuchi, K

    1997-01-01

    The Senescence-Accelerated Mouse (SAM) strains are unique and appropriate models for genetic studies on aging because the SAMP strains have an "accelerated senescence" phenotype for which the SAMR strains are controls, and each SAMP strain has a strain-specific age-associated disorder. Furthermore, because they have gone through sufficient generations of sister-brother mating, they can be considered inbred strains, which can be analyzed genetically. There are now 11 SAMP strains and 3 SAMR strains descended from the progenitor litters. Analysis with the Gompertz function shows that the SAMP strains have the same initial mortality rate (IMR) as the SAMR strains but a shorter mortality rate doubling time (MRDT), presumably due to genes that accelerated the rate of senescence in the SAMP strains. This accelerated senescence may also occur in cultured fibroblast-like cells. We performed molecular genetic characterization of all the SAM strains to acquire a base of genetic information from which we could develop hypotheses on the mechanism of development of SAM strains and genetic factors that contribute to accelerated senescence. PMID:9088910

  16. Differential gene expression before and after ionizing radiation of subcutaneous fibroblasts identifies breast cancer patients resistant to radiation-induced fibrosis

    International Nuclear Information System (INIS)

    Background and purpose: Differentially gene expression between patients with either very low or very high risk of radiation-induced fibrosis (RIF) in patient-derived fibroblasts after irradiation has previously been reported. In the present study, we are investigating the robustness of radiation-induced changes in gene expression in fibroblasts, whether differential expression is more pronounced when looking at the fold induction levels, taking into account the differences in background expression levels between patients, and whether there is a linear correlation between individual risk of RIF and changes in radiation-induced gene expression in fibroblasts. Material and methods: Gene expression was analysed by quantitative real-time PCR before and after a fractionated scheme with 3 x 3.5 Gy/3 days in fibroblasts derived from 26 patients with breast cancer treated with post-mastectomy radiotherapy. Results: Robust radiation-induced changes in gene expression were observed, with differential gene expression between low and high risk patients being most pronounced for the fold induction level ('after' value divided by 'before' value for each patient). When including patients with intermediate risk, there was no linear correlation between individual risk of RIF and differential expression of the genes investigated. Rather, differential gene expression could divide patients into two clearly separated groups, a larger, sensitive group and a smaller resistant group. Conclusions: Differential gene expression in irradiated fibroblasts might be an important tool in the identification of differences in the genetic background between patients with variable risk of RIF, and in the identification of new targets for prevention and intervention of the fibrotic process

  17. Stimulation of MMP-11 (stromelysin-3) expression in mouse fibroblasts by cytokines, collagen and co-culture with human breast cancer cell lines

    International Nuclear Information System (INIS)

    Matrix metalloproteinases (MMPs) are central to degradation of the extracellular matrix and basement membrane during both normal and carcinogenic tissue remodeling. MT1-MMP (MMP-14) and stromelysin-3 (MMP-11) are two members of the MMP family of proteolytic enzymes that have been specifically implicated in breast cancer progression. Expressed in stromal fibroblasts adjacent to epithelial tumour cells, the mechanism of MT1-MMP and MMP-11 induction remains unknown. To investigate possible mechanisms of induction, we examined the effects of a number of plausible regulatory agents and treatments that may physiologically influence MMP expression during tumour progression. Thus NIH3T3 and primary mouse embryonic fibroblasts (MEFs) were: a) treated with the cytokines IL-1β, IL-2, IL-6, IL-8 and TGF-β for 3, 6, 12, 24, and 48 hours; b) grown on collagens I, IV and V; c) treated with fibronectin, con-A and matrigel; and d) co-cultured with a range of HBC (human breast cancer) cell lines of varied invasive and metastatic potential. Competitive quantitative RT-PCR indicated that MMP-11 expression was stimulated to a level greater than 100%, by 48 hour treatments of IL-1β, IL-2, TGF-β, fibronectin and collagen V. No other substantial changes in expression of MMP-11 or MT1-MMP in either tested fibroblast culture, under any treatment conditions, were observed. We have demonstrated significant MMP-11 stimulation in mouse fibroblasts using cytokines, matrix constituents and HBC cell lines, and also some inhibition of MT1-MMP. Our data suggest that the regulation of these genes in the complex stromal-epithelial interactions that occur in human breast carcinoma, is influenced by several mechanisms

  18. Stimulation of MMP-11 (stromelysin-3 expression in mouse fibroblasts by cytokines, collagen and co-culture with human breast cancer cell lines

    Directory of Open Access Journals (Sweden)

    Matthaei Klaus I

    2004-07-01

    Full Text Available Abstract Background Matrix metalloproteinases (MMPs are central to degradation of the extracellular matrix and basement membrane during both normal and carcinogenic tissue remodeling. MT1-MMP (MMP-14 and stromelysin-3 (MMP-11 are two members of the MMP family of proteolytic enzymes that have been specifically implicated in breast cancer progression. Expressed in stromal fibroblasts adjacent to epithelial tumour cells, the mechanism of MT1-MMP and MMP-11 induction remains unknown. Methods To investigate possible mechanisms of induction, we examined the effects of a number of plausible regulatory agents and treatments that may physiologically influence MMP expression during tumour progression. Thus NIH3T3 and primary mouse embryonic fibroblasts (MEFs were: a treated with the cytokines IL-1β, IL-2, IL-6, IL-8 and TGF-β for 3, 6, 12, 24, and 48 hours; b grown on collagens I, IV and V; c treated with fibronectin, con-A and matrigel; and d co-cultured with a range of HBC (human breast cancer cell lines of varied invasive and metastatic potential. Results Competitive quantitative RT-PCR indicated that MMP-11 expression was stimulated to a level greater than 100%, by 48 hour treatments of IL-1β, IL-2, TGF-β, fibronectin and collagen V. No other substantial changes in expression of MMP-11 or MT1-MMP in either tested fibroblast culture, under any treatment conditions, were observed. Conclusion We have demonstrated significant MMP-11 stimulation in mouse fibroblasts using cytokines, matrix constituents and HBC cell lines, and also some inhibition of MT1-MMP. Our data suggest that the regulation of these genes in the complex stromal-epithelial interactions that occur in human breast carcinoma, is influenced by several mechanisms.

  19. Identification of 30 protein species involved in replicative senescence and stress-induced premature senescence

    DEFF Research Database (Denmark)

    Dierick, Jean François; Kalume, Dário E; Wenders, Frédéric;

    2002-01-01

    Exposure of human proliferative cells to subcytotoxic stress triggers stress-induced premature senescence (SIPS) which is characterized by many biomarkers of replicative senescence. Proteomic comparison of replicative senescence and stress-induced premature senescence indicates that, at the level...

  20. Fibroblast growth factor receptor 1 amplification in non-small cell lung cancer by quantitative real-time PCR.

    Directory of Open Access Journals (Sweden)

    Shirish M Gadgeel

    Full Text Available INTRODUCTION: Amplification of the fibroblast growth factor receptor 1 (FGFR1 gene has been described in tumors of non-small-cell lung cancer (NSCLC patients. Prior reports showed conflicting rates of amplification frequency and clinical relevance. MATERIALS AND METHODS: We developed a reliable real-time quantitative PCR assay to assess the frequency of FGFR1 amplification and assessed the optimal cutoff level of amplification for clinical application. RESULTS: In a training cohort of 203 NSCLCs, we established that a 3.5-fold amplification optimally divided patients into groups with different survival rates with a clear threshold level. Those with FGFR1 amplification levels above 3.5-fold had an inferior survival. These data were confirmed in a validation cohort of 142 NSCLC. After adjusting for age, sex, performance status, stage, and histology, patients with FGFR1 amplification levels above 3.5 fold had a hazard ratio of 2.91 (95% CI- 1.14, 7.41; pvalue-0.025 for death in the validation cohort. The rates of FGFR1 amplification using the cutoff level of 3.5 were 5.1% in squamous cell and 4.1% in adenocarcinomas. There was a non-significant trend towards higher amplifications rates in heavy smokers (> 15 pack-years of cigarette consumption as compared to light smokers. DISCUSSION: Our data suggest that a 3.5-fold amplification of FGFR1 is of clinical importance in NSCLC. Our cutpoint analysis showed a clear threshold effect for the impact of FGFR1 amplification on patients' survival, which can be used as an initial guide for patient selection in trials assessing efficacy of novel FGFR inhibitors.

  1. Circulating Fibroblast Growth Factor 21 (Fgf21) as Diagnostic and Prognostic Biomarker in Renal Cancer

    Science.gov (United States)

    Knott, ME; Minatta, JN; Roulet, L; Gueglio, G; Pasik, L; Ranuncolo, SM; Nuñez, M; Puricelli, L; De Lorenzo, MS

    2016-01-01

    Background The finding of new biomarkers is needed to have a better sub-classification of primary renal tumors (RCC) as well as more reliable predictors of outcome and therapy response. In this study, we evaluated the role of circulating FGF21, an endocrine factor, as a diagnostic and prognostic biomarker for ccRCC. Materials and Methods Serum samples from healthy controls (HC), clear cell and chromophobe RCC cancer patients were obtained from the serum biobank “Biobanco Público de Muestras Séricas Oncológicas” (BPMSO) of the “Instituto de Oncología “Ángel H. Roffo”. Serum FGF21 and leptin were measured by ELISA while other metabolic markers were measured following routinely clinical procedures. Results One of our major findings was that FGF21 levels were significantly increased in ccRCC patients compared with HC. Moreover, we showed an association between the increased serum FGF21 levels and the shorter disease free survival in a cohort of 98 ccRCC patients, after adjustment for other predictors of outcome. Conclusion Our results suggest that higher FGF21 serum level is an independent prognostic biomarker, associated with worse free-disease survival. PMID:27358750

  2. Transformable Peptide Nanocarriers for Expeditious Drug Release and Effective Cancer Therapy via Cancer‐Associated Fibroblast Activation

    OpenAIRE

    Ji, Tianjiao; Zhao, Ying; Ding, Yanping; Wang, Jing; Zhao, Ruifang; Lang, Jiayan; Qin, Hao; Liu, Xiaoman; Shi, Jian; Tao, Ning; Qin, Zhihai; Nie, Guangjun; Zhao, Yuliang

    2015-01-01

    Abstract A novel cleavable amphiphilic peptide (CAP) was designed to be specifically responsive to fibroblast activation protein‐α (FAP‐α), a protease specifically expressed on the surface of cancer‐associated fibroblasts. The CAP self‐assembled into fiber‐like nanostructures in solution, while the presence of hydrophobic chemotherapeutic drugs readily transformed the assemblies into drug‐loaded spherical nanoparticles. The disassembly of these nanoparticles (CAP‐NPs) upon FAP‐α cleavage resu...

  3. Inactivation of the FoxO3a transcription factor is associated with the production of reactive oxygen species during protein kinase CK2 downregulation-mediated senescence in human colon cancer and breast cancer cells.

    Science.gov (United States)

    Park, Seong-Yeol; Bae, Young-Seuk

    2016-09-01

    We previously showed that protein kinase CK2 downregulation mediates senescence through the reactive oxygen species (ROS)-p53-p21(Cip1/WAF1) pathway in various human cells. In the present study, we investigated whether the FoxO3a transcription factor is associated with ROS production during CK2 downregulation-induced senescence in human colon cancer HCT116 and breast cancer MCF-7 cells. FoxO3a overexpression suppressed ROS production and p53 stabilization induced by a CK2α knockdown. CK2α downregulation induced nuclear export of FoxO3a through stimulation of AKT-mediated phosphorylation of FoxO3a and decreased transcription of its target genes (Cu/ZnSOD, MnSOD, and catalase). In contrast, CK2α overexpression inhibited AKT-mediated FoxO3a phosphorylation. This resulted in nuclear accumulation of FoxO3a, and elevated expression of its target genes. Therefore, these data indicate for the first time that CK2 downregulation stimulates ROS generation by inhibiting FoxO3a during premature senescence in human colon and breast cancer cells. PMID:27470586

  4. Characterization of fibroblast growth factor receptor 2 overexpression in the human breast cancer cell line SUM-52PE

    International Nuclear Information System (INIS)

    The fibroblast growth factor receptor (FGFR)2 gene has been shown to be amplified in 5-10% of breast cancer patients. A breast cancer cell line developed in our laboratory, SUM-52PE, was shown to have a 12-fold amplification of the FGFR2 gene, and FGFR2 message was found to be overexpressed 40-fold in SUM-52PE cells as compared with normal human mammary epithelial (HME) cells. Both human breast cancer (HBC) cell lines and HME cells expressed two FGFR2 isoforms, whereas SUM-52PE cells overexpressed those two isoforms, as well as several unique FGFR2 polypeptides. SUM-52PE cells expressed exclusively FGFR2-IIIb isoforms, which are high-affinity receptors for fibroblast growth factor (FGF)-1 and FGF-7. Differences were identified in the expression of the extracellular Ig-like domains, acid box and carboxyl termini, and several variants not previously reported were isolated from these cells. The FGFR family of receptor tyrosine kinases includes four members, all of which are highly alternatively spliced and glycosylated. For FGFR2, alternative splicing of the second half of the third Ig-like domain, involving exons IIIb and IIIc, is a mutually exclusive choice that affects ligand binding specificity and affinity [1,2,3]. It appears that the second half of the third Ig-like domain can dictate high affinity for FGF-2 or keratinocyte growth factor (KGF), whereas affinity for FGF-1 appears to remain the same [3]. Alternative splicing of the carboxyl terminus has been shown to involve at least two different exons that can produce at least three different variants. The C1-type and C2-type carboxyl termini are encoded by the same exon, and have two different splice acceptor sites, whereas the C3-type carboxyl terminus is encoded by a separate exon [4]. The biologic significance of the C1 carboxyl terminus, as compared with the shorter C3 variant found primarily in tumorigenic samples, has been studied in NIH3T3 transfection assays, in which C3 variants were able to produce

  5. Regulation of the PML tumor suppressor in drug-induced senescence of human normal and cancer cells by JAK/STAT-mediated signaling

    Czech Academy of Sciences Publication Activity Database

    Hubáčková, Soňa; Nováková, Zora; Krejčíková, Kateřina; Košař, Martin; Dobrovolná, Jana; Dušková, Pavlína; Hanzlíková, Hana; Vančurová, Markéta; Barath, P.; Bartek, J.; Hodný, Zdeněk

    2010-01-01

    Roč. 9, č. 15 (2010), s. 3085-3099. ISSN 1538-4101 R&D Projects: GA AV ČR IAA500390501; GA ČR GA204/08/1418; GA ČR GA301/08/0353 Institutional research plan: CEZ:AV0Z50520514 Keywords : PML tumor suppressor * cellular senescence * JAK-STAT signaling pathway Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.999, year: 2010

  6. Mitochondrial dysfunction accounts for the stochastic heterogeneity in telomere-dependent senescence.

    Directory of Open Access Journals (Sweden)

    João F Passos

    2007-05-01

    Full Text Available Aging is an inherently stochastic process, and its hallmark is heterogeneity between organisms, cell types, and clonal populations, even in identical environments. The replicative lifespan of primary human cells is telomere dependent; however, its heterogeneity is not understood. We show that mitochondrial superoxide production increases with replicative age in human fibroblasts despite an adaptive UCP-2-dependent mitochondrial uncoupling. This mitochondrial dysfunction is accompanied by compromised [Ca(2+]i homeostasis and other indicators of a retrograde response in senescent cells. Replicative senescence of human fibroblasts is delayed by mild mitochondrial uncoupling. Uncoupling reduces mitochondrial superoxide generation, slows down telomere shortening, and delays formation of telomeric gamma-H2A.X foci. This indicates mitochondrial production of reactive oxygen species (ROS as one of the causes of replicative senescence. By sorting early senescent (SES cells from young proliferating fibroblast cultures, we show that SES cells have higher ROS levels, dysfunctional mitochondria, shorter telomeres, and telomeric gamma-H2A.X foci. We propose that mitochondrial ROS is a major determinant of telomere-dependent senescence at the single-cell level that is responsible for cell-to-cell variation in replicative lifespan.

  7. Dextran sulphate crowding and sodium deoxycholate lysis of primary breast fibroblast cells achieve extracellular matrix deposition and decellularization for breast cancer stem cell culture

    Directory of Open Access Journals (Sweden)

    Aroem Naruni

    2016-01-01

    .Extracellular matrix provides tissue integrity, acts as a native scaffold for cell attachment and interaction and alsoserves as reservoir for growth factors. The aim of this experiment w asto achieve the deposition and decellularizationof ECM.Methods: Cells crowder have been developed to increase ECM deposit in the primary breast fibroblast cells layerobtained from isolation of single cell from breast mammoplasty specimen. Five hundred kDa dextran was addedinto DMEM medium containing 0.5% fetal bovine serum (FBS and 100 μm of L-ascorbic acid 2-phosphate. Afterseven days, cells were lysed by sodium deoxycholate (DOC. Results were observed in a fluorescence microscope.Results: Extracellular matrix deposition and decellularization of primary breast fibroblast cells were detected byusing extracellular matrix protein, fibronectin via rabbit anti human fibronectin and anti-rabbit IgG conjugated withAlexa Fluor 488.Conclusion: Dextran sulphate increased extracellular matrix deposit in primary breast fibroblast cell layer and thetreatment with sodium deoxycolate lysed cells resulted in extracellular matrix decellularization. (Health ScienceJournal of Indonesia 2015;6:43-7Keywords: extracellular matrix, breast cancer stem cell, breast fibroblast cell

  8. MicroRNA Regulation of Ionizing Radiation-Induced Premature Senescence

    International Nuclear Information System (INIS)

    Purpose: MicroRNAs (miRNAs) have emerged as critical regulators of many cellular pathways. Ionizing radiation (IR) exposure causes DNA damage and induces premature senescence. However, the role of miRNAs in IR-induced senescence has not been well defined. Thus, the purpose of this study was to identify and characterize senescence-associated miRNAs (SA-miRNAs) and to investigate the role of SA-miRNAs in IR-induced senescence. Methods and Materials: In human lung (WI-38) fibroblasts, premature senescence was induced either by IR or busulfan (BU) treatment, and replicative senescence was accomplished by serial passaging. MiRNA microarray were used to identify SA-miRNAs, and real-time reverse transcription (RT)-PCR validated the expression profiles of SA-miRNAs in various senescent cells. The role of SA-miRNAs in IR-induced senescence was characterized by knockdown of miRNA expression, using anti-miRNA oligonucleotides or by miRNA overexpression through the transfection of pre-miRNA mimics. Results: We identified eight SA-miRNAs, four of which were up-regulated (miR-152, -410, -431, and -493) and four which were down-regulated (miR-155, -20a, -25, and -15a), that are differentially expressed in both prematurely senescent (induced by IR or BU) and replicatively senescent WI-38 cells. Validation of the expression of these SA-miRNAs indicated that down-regulation of miR-155, -20a, -25, and -15a is a characteristic miRNA expression signature of cellular senescence. Functional analyses revealed that knockdown of miR-155 or miR-20a, but not miR-25 or miR-15a, markedly enhanced IR-induced senescence, whereas ectopic overexpression of miR-155 or miR-20a significantly inhibited senescence induction. Furthermore, our studies indicate that miR-155 modulates IR-induced senescence by acting downstream of the p53 and p38 mitogen-activated protein kinase (MAPK) pathways and in part via regulating tumor protein 53-induced nuclear protein 1 (TP53INP1) expression. Conclusion: Our

  9. Biological Monitoring of Hexavalent Chromium and Serum Levels of the Senescence Biomarker Apolipoprotein J/Clusterin in Welders

    OpenAIRE

    Vassilios Makropoulos; Gonos, Efstathios S.; Magda Lourda; Trougakos, Ioannis P.; Xenophon Cominos; Alexopoulos, Evangelos C.

    2008-01-01

    Welding fumes contain metals and other toxic substances known or strongly suspected to be related with oxidative stress and premature cellular senescence. Apolipoprotein J/Clusterin (ApoJ/CLU) is a glycoprotein that is differentially regulated in various physiological and disease states including ageing and age-related diseases. In vitro data showed that exposure of human diploid fibroblasts to hexavalent chromium (Cr(VI)) resulted in premature senescence and significant upregulation of the A...

  10. The case for negative senescence

    DEFF Research Database (Denmark)

    Vaupel, James W; Baudisch, Annette; Dölling, Martin;

    2004-01-01

    Negative senescence is characterized by a decline in mortality with age after reproductive maturity, generally accompanied by an increase in fecundity. Hamilton (1966) ruled out negative senescence: we adumbrate the deficiencies of his model. We review empirical studies of various plants and some...

  11. PTTG1 attenuates drug-induced cellular senescence.

    Directory of Open Access Journals (Sweden)

    Yunguang Tong

    Full Text Available As PTTG1 (pituitary tumor transforming gene abundance correlates with adverse outcomes in cancer treatment, we determined mechanisms underlying this observation by assessing the role of PTTG1 in regulating cell response to anti-neoplastic drugs. HCT116 cells devoid of PTTG1 (PTTG1(-/- exhibited enhanced drug sensitivity as assessed by measuring BrdU incorporation in vitro. Apoptosis, mitosis catastrophe or DNA damage were not detected, but features of senescence were observed using low doses of doxorubicin and TSA. The number of drug-induced PTTG1(-/- senescent cells increased ∼4 fold as compared to WT PTTG1-replete cells (p<0.001. p21, an important regulator of cell senescence, was induced ∼3 fold in HCT116 PTTG1(-/- cells upon doxorubicin or Trichostatin A treatment. Binding of Sp1, p53 and p300 to the p21 promoter was enhanced in PTTG1(-/- cells after treatment, suggesting transcriptional regulation of p21. p21 knock down abrogated the observed senescent effects of these drugs, indicating that PTTG1 likely suppresses p21 to regulate drug-induced senescence. PTTG1 also regulated SW620 colon cancer cells response to doxorubicin and TSA mediated by p21. Subcutaneously xenografted PTTG1(-/- HCT116 cells developed smaller tumors and exhibited enhanced responses to doxorubicin. PTTG1(-/- tumor tissue derived from excised tumors exhibited increased doxorubicin-induced senescence. As senescence is a determinant of cell responses to anti-neoplastic treatments, these findings suggest PTTG1 as a tumor cell marker to predict anti-neoplastic treatment outcomes.

  12. Asporin Is a Fibroblast-Derived TGF-β1 Inhibitor and a Tumor Suppressor Associated with Good Prognosis in Breast Cancer.

    Directory of Open Access Journals (Sweden)

    Pamela Maris

    2015-09-01

    Full Text Available Breast cancer is a leading malignancy affecting the female population worldwide. Most morbidity is caused by metastases that remain incurable to date. TGF-β1 has been identified as a key driving force behind metastatic breast cancer, with promising therapeutic implications.Employing immunohistochemistry (IHC analysis, we report, to our knowledge for the first time, that asporin is overexpressed in the stroma of most human breast cancers and is not expressed in normal breast tissue. In vitro, asporin is secreted by breast fibroblasts upon exposure to conditioned medium from some but not all human breast cancer cells. While hormone receptor (HR positive cells cause strong asporin expression, triple-negative breast cancer (TNBC cells suppress it. Further, our findings show that soluble IL-1β, secreted by TNBC cells, is responsible for inhibiting asporin in normal and cancer-associated fibroblasts. Using recombinant protein, as well as a synthetic peptide fragment, we demonstrate the ability of asporin to inhibit TGF-β1-mediated SMAD2 phosphorylation, epithelial to mesenchymal transition, and stemness in breast cancer cells. In two in vivo murine models of TNBC, we observed that tumors expressing asporin exhibit significantly reduced growth (2-fold; p = 0.01 and metastatic properties (3-fold; p = 0.045. A retrospective IHC study performed on human breast carcinoma (n = 180 demonstrates that asporin expression is lowest in TNBC and HER2+ tumors, while HR+ tumors have significantly higher asporin expression (4-fold; p = 0.001. Assessment of asporin expression and patient outcome (n = 60; 10-y follow-up shows that low protein levels in the primary breast lesion significantly delineate patients with bad outcome regardless of the tumor HR status (area under the curve = 0.87; 95% CI 0.78-0.96; p = 0.0001. Survival analysis, based on gene expression (n = 375; 25-y follow-up, confirmed that low asporin levels are associated with a reduced likelihood of

  13. Mitochondrial DNA deletion and impairment of mitochondrial biogenesis by reactive oxygen species in ionizing radiation-induced premature senescence

    International Nuclear Information System (INIS)

    The aim of this study was to determine whether an increase of ROS level in cellular senescence induced by IR could mediate mtDNA deletion via impairment of mitochondria biogenesis in IMR-90 human lung fibroblast cells. Our results showed that IR induced cellular senescence, intracellular ROS, and mtDNA deletion, and in particular, suppressed the expression of mitochondrial biogenesis genes (NRF-1, TFAM). Furthermore, these IR-induced events were abolished using a potent antioxidant, NAC, which suggests that ROS is a key cause of mtDNA deletion in IR-induced cellular senescence, and that the alteration of mitochondrial biogenesis may mediate these processes

  14. Mitochondrial DNA deletion and impairment of mitochondrial biogenesis by reactive oxygen species in ionizing radiation-induced premature senescence

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Hyeon Soo; Jung, U Hee; Jo, Sung Kee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    The aim of this study was to determine whether an increase of ROS level in cellular senescence induced by IR could mediate mtDNA deletion via impairment of mitochondria biogenesis in IMR-90 human lung fibroblast cells. Our results showed that IR induced cellular senescence, intracellular ROS, and mtDNA deletion, and in particular, suppressed the expression of mitochondrial biogenesis genes (NRF-1, TFAM). Furthermore, these IR-induced events were abolished using a potent antioxidant, NAC, which suggests that ROS is a key cause of mtDNA deletion in IR-induced cellular senescence, and that the alteration of mitochondrial biogenesis may mediate these processes

  15. Markers of cellular senescence. Telomere shortening as a marker of cellular senescence.

    Science.gov (United States)

    Bernadotte, Alexandra; Mikhelson, Victor M; Spivak, Irina M

    2016-01-01

    The cellular senescence definition comes to the fact of cells irreversible proliferation disability. Besides the cell cycle arrest, senescent cells go through some morphological, biochemical, and functional changes which are the signs of cellular senescence. The senescent cells (including replicative senescence and stress-induced premature senescence) of all the tissues look alike. They are metabolically active and possess the set of characteristics in vitro and in vivo, which are known as biomarkers of aging and cellular senescence. Among biomarkers of cellular senescence telomere shortening is a rather elegant frequently used biomarker. Validity of telomere shortening as a marker for cellular senescence is based on theoretical and experimental data. PMID:26805432

  16. Regulation of a senescence checkpoint response by the E2F1 transcription factor and p14ARF tumor suppressor

    Energy Technology Data Exchange (ETDEWEB)

    Dimri, Goberdhan P.; Itahana, Koji; Acosta, Meileen; Campisi, Judith

    1999-11-05

    Normal cells do not divide indefinitely due to a process known as replicative senescence. Human cells arrest growth with a senescent phenotype when they acquire one or more critically short telomere as a consequence of cell division. Recent evidence suggests that certain types of DNA damage, chromatin remodeling, or oncogenic forms of Rasor Raf can also elicit a senescence response. We show here that E2F1, a multifunctional transcription factor that binds the retinoblastoma (pRb) tumor suppressor and can either promote or suppress tumorigenesis, induces a senescent phenotype when overexpressed in normal human fibroblasts. Normal human cells stably arrested proliferation and expressed several markers of replicative senescence in response to E2F1. This activity of E2F1 was independent of its pRb binding activity, but dependent on its ability to stimulate gene expression. The E2F1 target gene critical for the senescence response appeared to be the p14ARF tumor suppressor. Replicatively senescent human fibroblasts overexpressed p14ARF, and ectopic expression of p14ARF in presenescent cells induced a phenotype similar to that induced by E2F1. Consistent with a critical role for p14ARF, cells with compromised p53 function were immune to senescence induction by E2F1, as were cells deficient in p14ARF. Our findings support the idea that the senescence response is a critical tumor suppressive mechanism, provide an explanation for the apparently paradoxical roles of E2F1 in oncogenesis, and identify p14ARF as a potentially important mediator of the senescent phenotype.

  17. Extracellular Matrix Modulates Morphology, Growth, Oxidative Stress Response and Functionality of Human Skin Fibroblasts during Aging In Vitro

    DEFF Research Database (Denmark)

    Jørgensen, Peter; Rattan, Suresh

    2014-01-01

    The Hayflick system of cellular aging and replicative senescence in vitro has been used widely in both basic and applied research in biogerontology. The state of replicative senescence is generally considered to be irreversible, but is modifiable by genetic and environmental manipulations. Some...... recent observations indicate that replicative lifespan, senescence and functionality of cells in vitro can be significantly affected by the quality of the extra cellular matrix (ECM). Following up on those reports, here we show that using the ECM prepared from early passage young cells, partial...... rejuvenation of serially passaged human facial skin fibroblasts was possible in pre-senescent middle-aged cells, but not in fully senescent late passage cells. ECM from young cells improved the appearance, viability, stress tolerance and wound healing ability of skin fibroblasts. Furthermore, young ECM...

  18. NAC transcription factors in senescence

    DEFF Research Database (Denmark)

    Podzimska-Sroka, Dagmara; O'Shea, Charlotte; Gregersen, Per L.;

    2015-01-01

    involving the hormone abscisic acid, Arabidopsis NAP promotes chlorophyll degradation, a hallmark of senescence. Furthermore, studies of the functional rice ortholog, OsNAP, suggest that NAC genes can be targeted to obtain specific changes in lifespan control and nutrient remobilization in crop plants. This...... domains determine the interactions in gene regulatory networks. Emerging local NAC-centered gene regulatory networks reveal complex molecular mechanisms of stress- and hormone-regulated senescence and basic physiological steps of the senescence process. For example, through molecular interactions...

  19. Regulation of cellular senescence by the essential caveolar component PTRF/Cavin-1

    Institute of Scientific and Technical Information of China (English)

    Lin Bai; Xiaoli Deng; Juanjuan Li; Miao Wang; Qian Li; Wei An; Deli A; Yu-Sheng Cong

    2011-01-01

    Polymerase I and transcript release factor (PTRF, also known as Cavin-1) is an essential component in the biogenesis and function of caveolae. Here, we show that PTRF expression is increased in senescent human fibroblasts.Importantly, overexpression of PTRF induced features characteristic of cellular senescence, whereas reduced PTRF expression extended the cellular replicative lifespan. Interestingly, we found that PTRF localized primarily to the nuclei of young and quiescent WI-38 human fibroblasts, but translocated to the cytosol and plasma membrane during cellular senescence. Furthermore, electron microscopic analysis demonstrated an increased number of caveolar structures in senescent and PTRF-transfected WI-38 cells. Our data suggest that the role of PTRF in cellular senes cence is dependent on its targeting to caveolae and its interaction with caveolin-l, which appeared to be regulated by the phosphorylation of PTRF. Taken together, our findings identify PTRF as a novel regulator of cellular senescence that acts through the p53/p21 and caveolar pathways.

  20. Effect of cell cycle inhibitor p19ARF on senescence of human diploid cell

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To investigate the effect of cell cycle inhibitor p19ARF on replicative senescence of human diploid cell, recombinant p19ARF eukaryotic expression vector was constructed and p19ARF gene was transfected into human diploid fibroblasts (WI-38 cells) by liposome-mediated transfection for overexpression. Then, the effects of p19ARF on replicative senescence of WI-38 cells were observed. The results re- vealed that, compared with control cells, the WI-38 cells in which p19ARF gene was introduced showed significant up-regulation of p53 and p21 expression level, decrease of cell generation by 10 12 generations, decline of cell growth rate with cell cycle being arrested at G1 phase, increase of positive rate of senescent marker SA-β-gal staining, and decrease of mitochondrial membrane potential. The morphology of the transfected fibroblasts presented the characteristics changes similar to senescent cells. These results indicated that high expression of p19ARF may promote the senescent process of human diploid cells.

  1. Nuclear accumulation of Yes-Associated Protein (YAP) maintains the survival of doxorubicin-induced senescent cells by promoting survivin expression.

    Science.gov (United States)

    Ma, Kai; Xu, Qing; Wang, Shuren; Zhang, Weina; Liu, Mei; Liang, Shufang; Zhu, Hongxia; Xu, Ningzhi

    2016-05-28

    Although chemotherapeutic drugs can induce senescence to prohibit further division of tumor cells, senescence could also promote tumorigenesis mainly through a senescence-associated secretory phenotype. Therefore, senescent tumor cells should be eliminated immediately to prevent drug resistance and recurrence. Here, we used a doxorubicin-induced senescence model to explore the mechanism underlying the survival of therapy-induced senescent cells. After low-dose doxorubicin treatment, tumor cells turned on a senescence program and became large and flattened, increasing their contact area with the extracellular matrix (ECM). Furthermore, Yes-associated protein (YAP) accumulated in the nucleus and YAP activity was increased in doxorubicin-induced senescent cells. Knockdown of YAP increased the sensitivity of cells to low-dose doxorubicin treatment, causing apoptosis rather than senescence. Moreover, the anti-apoptotic gene survivin, a YAP target gene, was overexpressed in senescent cells. Inhibition of survivin could lead to selective elimination of senescent cells through apoptosis. Our study indicates that nuclear accumulation of YAP could promote the survival of senescent cells by increasing survivin expression. Therefore, targeting YAP or survivin might be a new strategy for clearing senescent cancer cells during drug treatment. PMID:26944315

  2. A new approach to cancer therapy due to appropriate uptake and retention kinetics of meta-tetrahydroxy-phenylchlorin in a human fibroblast cell line.

    Science.gov (United States)

    Wierrani, F; Fiedler, D; Schnitzhofer, G; Stewart, J C; Gharehbaghi, K; Henry, M; Grin, W; Grünberger, W; Krammer, B

    1996-04-01

    Studies have shown that meta-tetrahydroxy-phenylchlorin is an efficient tumor targeting agent for laser photodynamic therapy. The effectiveness of this approach for cancer treatment depends on drug concentration, incubation time and extracellular protein. We studied uptake and retention kinetics of mTHPC in a human fibroblast cell line. Our results clearly demonstrate a difference in the amount of extracellular mTHPC at an incubation temperature of 37 degrees C compared to 20 degrees C and 4 degrees C. pH-values were always constant and not responsible for the increase. Furthermore, both absorption and fluorescence of mTHPC increase when incubated at normal human body temperature. Incubation of human fibroblast cells with mTHPC (10 micg/mL) showed that intracellular mTHPC increases in a linear manner reaching saturation after 24 hours and declining until 48 hours with concommitant increase of supernatant mTHPC. Therefore, we believe that tumor cells can be treated optimally with PDT following a delay > 24 hours after drug administration with a minimum of damage to surrounding normal tissues. PMID:8937740

  3. IGF-I enhances cellular senescence via the reactive oxygen species-p53 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Handayaningsih, Anastasia-Evi; Takahashi, Michiko; Fukuoka, Hidenori; Iguchi, Genzo; Nishizawa, Hitoshi; Yamamoto, Masaaki; Suda, Kentaro [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe (Japan); Takahashi, Yutaka, E-mail: takahash@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe (Japan)

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Cellular senescence plays an important role in tumorigenesis and aging process. Black-Right-Pointing-Pointer We demonstrated IGF-I enhanced cellular senescence in primary confluent cells. Black-Right-Pointing-Pointer IGF-I enhanced cellular senescence in the ROS and p53-dependent manner. Black-Right-Pointing-Pointer These results may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging. -- Abstract: Cellular senescence is characterized by growth arrest, enlarged and flattened cell morphology, the expression of senescence-associated {beta}-galactosidase (SA-{beta}-gal), and by activation of tumor suppressor networks. Insulin-like growth factor-I (IGF-I) plays a critical role in cellular growth, proliferation, tumorigenesis, and regulation of aging. In the present study, we show that IGF-I enhances cellular senescence in mouse, rat, and human primary cells in the confluent state. IGF-I induced expression of a DNA damage marker, {gamma}H2AX, the increased levels of p53 and p21 proteins, and activated SA-{beta}-gal. In the confluent state, an altered downstream signaling of IGF-I receptor was observed. Treatment with a reactive oxygen species (ROS) scavenger, N-acetylcystein (NAC) significantly suppressed induction of these markers, indicating that ROS are involved in the induction of cellular senescence by IGF-I. In p53-null mouse embryonic fibroblasts, the IGF-I-induced augmentation of SA-{beta}-gal and p21 was inhibited, demonstrating that p53 is required for cellular senescence induced by IGF-I. Thus, these data reveal a novel pathway whereby IGF-I enhances cellular senescence in the ROS and p53-dependent manner and may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging.

  4. AP4 directly downregulates p16 and p21 to suppress senescence and mediate transformation

    OpenAIRE

    Jackstadt, R; Jung, P.; Hermeking, H

    2013-01-01

    Here we analyzed the function of the c-MYC-inducible basic helix–loop–helix leucine-zipper transcription factor AP4 in AP4-deficient mouse embryo fibroblasts (MEFs). Loss of AP4 resulted in premature senescence and resistance towards immortalization. Senescence was accompanied by induction of the cyclin-dependent kinase inhibitor-encoding genes p16, a known tumor suppressor, and p21, a previously described target for repression by AP4. Notably, AP4 directly repressed p16 expression via conser...

  5. Inhibition of HDAC increases the senescence induced by natural polyphenols in glioma cells.

    Science.gov (United States)

    Vargas, José E; Filippi-Chiela, Eduardo C; Suhre, Tais; Kipper, Franciele C; Bonatto, Diego; Lenz, Guido

    2014-08-01

    Cellular senescence is an irreversible block of cellular division, and induction of senescence is being considered for treatment of many cancer types, mainly those resistant to classical pro-apoptotic therapies. Resveratrol (Rsv) and quercetin (Quer), two natural polyphenols, are able to induce senescence in different cancer models, including gliomas, the most common and aggressive primary brain tumor. These polyphenols modulate the activity of several proteins involved in cell growth and death in cancer cells, including histone deacetylases (HDAC), but the role of HDAC in senescence induced by Rsv and Quer is unclear. The HDAC inhibitor sodium butyrate (NaB) potentiated the pro-senescent effect of Rsv and Quer in human and rat glioma cell lines but not in normal rat astrocytes. Furthermore, the increment of Quer-induced senescence by NaB was accompanied by an increase of reactive oxygen species levels and an increment of the number of cells with nuclear abnormalities. Altogether, these data support a positive role of HDAC inhibition on the senescence induced by these polyphenols, and therefore co-treatment of HDAC inhibitors and polyphenols emerges as a potential alternative for gliomas. PMID:25070040

  6. Derepression of hTERT gene expression promotes escape from oncogene-induced cellular senescence.

    Science.gov (United States)

    Patel, Priyanka L; Suram, Anitha; Mirani, Neena; Bischof, Oliver; Herbig, Utz

    2016-08-23

    Oncogene-induced senescence (OIS) is a critical tumor-suppressing mechanism that restrains cancer progression at premalignant stages, in part by causing telomere dysfunction. Currently it is unknown whether this proliferative arrest presents a stable and therefore irreversible barrier to cancer progression. Here we demonstrate that cells frequently escape OIS induced by oncogenic H-Ras and B-Raf, after a prolonged period in the senescence arrested state. Cells that had escaped senescence displayed high oncogene expression levels, retained functional DNA damage responses, and acquired chromatin changes that promoted c-Myc-dependent expression of the human telomerase reverse transcriptase gene (hTERT). Telomerase was able to resolve existing telomeric DNA damage response foci and suppressed formation of new ones that were generated as a consequence of DNA replication stress and oncogenic signals. Inhibition of MAP kinase signaling, suppressing c-Myc expression, or inhibiting telomerase activity, caused telomere dysfunction and proliferative defects in cells that had escaped senescence, whereas ectopic expression of hTERT facilitated OIS escape. In human early neoplastic skin and breast tissue, hTERT expression was detected in cells that displayed features of senescence, suggesting that reactivation of telomerase expression in senescent cells is an early event during cancer progression in humans. Together, our data demonstrate that cells arrested in OIS retain the potential to escape senescence by mechanisms that involve derepression of hTERT expression. PMID:27503890

  7. Abnormal phenotype of cultured fibroblasts in human skin with chronic radiotherapy damage

    International Nuclear Information System (INIS)

    Purpose: The pathophysiological aspects of radiation-induced fibrosis (RIF) have not been well characterized. We therefore cultured human fibroblasts from samples of skin with RIF to investigate the long-term effects of therapeutic irradiation. Materials and methods: Biopsies of normal and RIF skin were obtained from patients previously irradiated for cancer, without recurrence. Cells were extracted from dermis samples by the outgrowth technique, seeded as monolayers and cultured at confluence. Enzyme activities and proteins were assayed, RNA was isolated and Northern blot analysis was performed on surviving cells between passages 2 and 5. Results: RIF cell cultures displayed heterogeneous fibroblasts populations. The initial outgrowth consisted of one-third small cells that floated rapidly, one-third spindle-shaped cells migrating far from the explant to form islets and one-third large pleiomorphic cells. In subsequent subcultures, surviving cells exhibited either myofibroblastic characteristics with a normal proliferative capacity or senescent morphology with a reduced proliferative capacity. These RIF cells had a brief finite lifespan, with dramatically reduced growth rate during their initial outgrowth and the following passages. Study of the antioxidant metabolism showed that Mn superoxide dismutase and catalase activities were significantly weaker in surviving RIF cells than healthy fibroblasts. These exhausted RIF cells exhibited no overexpression of transforming growth factor β or tissue inhibitor of metalloproteinase. Conclusion: Irradiation may lead to apparently contradictory effects such as fibrosis and necrosis in clinical practice. In cell culture, we observed two main cellular phenotypes which may be related to both processes, i.e. myofibroblast-like cells and fibrocyte-like cells. These two phenotypes may represent two steps in the differentiation induced as a long-term effect of therapeutic irradiation of the skin. Cell culture probably

  8. Transfer of malignant trait to BRCA1 deficient human fibroblasts following exposure to serum of cancer patients

    OpenAIRE

    Hamam, Dana; Abdouh, Mohamed; Gao, Zu-hua; Arena, Vincenzo; Arena, Manuel; Arena, Goffredo Orazio

    2016-01-01

    Background It was reported that metastases might occur via transfer of biologically active blood circulating molecules from the primary tumor to distant organs rather than only migration of cancer cells. We showed in an earlier study that exposure of immortalized human embryonic kidney cells (HEK 293) to cancer patient sera, induce their transformation into undifferentiated cancers due to a horizontal transfer of malignant traits. In the present work, we tested the hypothesis that even other ...

  9. ATM Couples Replication Stress and Metabolic Reprogramming during Cellular Senescence

    Directory of Open Access Journals (Sweden)

    Katherine M. Aird

    2015-05-01

    Full Text Available Replication stress induced by nucleotide deficiency plays an important role in cancer initiation. Replication stress in primary cells typically activates the cellular senescence tumor-suppression mechanism. Senescence bypass correlates with development of cancer, a disease characterized by metabolic reprogramming. However, the role of metabolic reprogramming in the cellular response to replication stress has been little explored. Here, we report that ataxia telangiectasia mutated (ATM plays a central role in regulating the cellular response to replication stress by shifting cellular metabolism. ATM inactivation bypasses senescence induced by replication stress triggered by nucleotide deficiency. This was due to restoration of deoxyribonucleotide triphosphate (dNTP levels through both upregulation of the pentose phosphate pathway via increased glucose-6-phosphate dehydrogenase (G6PD activity and enhanced glucose and glutamine consumption. These phenotypes were mediated by a coordinated suppression of p53 and upregulation of c-MYC downstream of ATM inactivation. Our data indicate that ATM status couples replication stress and metabolic reprogramming during senescence.

  10. Oxidative stress induces senescence in human mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Brandl, Anita [Department of Anesthesiology, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Meyer, Matthias; Bechmann, Volker [Department of Trauma Surgery, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Nerlich, Michael [Department of Anesthesiology, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Angele, Peter, E-mail: Peter.Angele@klinik.uni-regensburg.de [Department of Trauma Surgery, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany)

    2011-07-01

    Mesenchymal stem cells (MSCs) contribute to tissue repair in vivo and form an attractive cell source for tissue engineering. Their regenerative potential is impaired by cellular senescence. The effects of oxidative stress on MSCs are still unknown. Our studies were to investigate into the proliferation potential, cytological features and the telomere linked stress response system of MSCs, subject to acute or prolonged oxidant challenge with hydrogen peroxide. Telomere length was measured using the telomere restriction fragment assay, gene expression was determined by rtPCR. Sub-lethal doses of oxidative stress reduced proliferation rates and induced senescent-morphological features and senescence-associated {beta}-galactosidase positivity. Prolonged low dose treatment with hydrogen peroxide had no effects on cell proliferation or morphology. Sub-lethal and prolonged low doses of oxidative stress considerably accelerated telomere attrition. Following acute oxidant insult p21 was up-regulated prior to returning to initial levels. TRF1 was significantly reduced, TRF2 showed a slight up-regulation. SIRT1 and XRCC5 were up-regulated after oxidant insult and expression levels increased in aging cells. Compared to fibroblasts and chondrocytes, MSCs showed an increased tolerance to oxidative stress regarding proliferation, telomere biology and gene expression with an impaired stress tolerance in aged cells.

  11. Oxidative stress induces senescence in human mesenchymal stem cells

    International Nuclear Information System (INIS)

    Mesenchymal stem cells (MSCs) contribute to tissue repair in vivo and form an attractive cell source for tissue engineering. Their regenerative potential is impaired by cellular senescence. The effects of oxidative stress on MSCs are still unknown. Our studies were to investigate into the proliferation potential, cytological features and the telomere linked stress response system of MSCs, subject to acute or prolonged oxidant challenge with hydrogen peroxide. Telomere length was measured using the telomere restriction fragment assay, gene expression was determined by rtPCR. Sub-lethal doses of oxidative stress reduced proliferation rates and induced senescent-morphological features and senescence-associated β-galactosidase positivity. Prolonged low dose treatment with hydrogen peroxide had no effects on cell proliferation or morphology. Sub-lethal and prolonged low doses of oxidative stress considerably accelerated telomere attrition. Following acute oxidant insult p21 was up-regulated prior to returning to initial levels. TRF1 was significantly reduced, TRF2 showed a slight up-regulation. SIRT1 and XRCC5 were up-regulated after oxidant insult and expression levels increased in aging cells. Compared to fibroblasts and chondrocytes, MSCs showed an increased tolerance to oxidative stress regarding proliferation, telomere biology and gene expression with an impaired stress tolerance in aged cells.

  12. Phenylbutyric acid induces the cellular senescence through an Akt/p21WAF1 signaling pathway

    International Nuclear Information System (INIS)

    Highlights: ► Phenylbutyric acid induces cellular senescence. ► Phenylbutyric acid activates Akt kinase. ► The knockdown of PERK also can induce cellular senescence. ► Akt/p21WAF1 pathway activates in PERK knockdown induced cellular senescence. -- Abstract: It has been well known that three sentinel proteins – PERK, ATF6 and IRE1 – initiate the unfolded protein response (UPR) in the presence of misfolded or unfolded proteins in the ER. Recent studies have demonstrated that upregulation of UPR in cancer cells is required to survive and proliferate. Here, we showed that long exposure to 4-phenylbutyric acid (PBA), a chemical chaperone that can reduce retention of unfolded and misfolded proteins in ER, induced cellular senescence in cancer cells such as MCF7 and HT1080. In addition, we found that treatment with PBA activates Akt, which results in p21WAF1 induction. Interestingly, the depletion of PERK but not ATF6 and IRE1 also induces cellular senescence, which was rescued by additional depletion of Akt. This suggests that Akt pathway is downstream of PERK in PBA induced cellular senescence. Taken together, these results show that PBA induces cellular senescence via activation of the Akt/p21WAF1 pathway by PERK inhibition.

  13. Inhibition of fibroblast growth factor 2-induced apoptosis involves survivin expression, protein kinase Cα activation and subcellular translocation of Smac in human small cell lung cancer cells

    Institute of Scientific and Technical Information of China (English)

    Desheng Xiao; Kuansong Wang; Jianhua Zhou; Huiqiu Cao; Zhenghao Deng; Yongbin Hu; Xiahui Qu; Jifang Wen

    2008-01-01

    To investigate the mechanism by which fibroblast growth factor 2 (FGF-2) inhibits apoptosis in the human small cell lung cancer cell line H446 subjected to serum starvation,apoptosis was evaluated by flow cytometry, Hoechst 33258 staining, caspase-3 activity, and DNA fragmentation.Survivin expression induced by FGF-2 and protein kinase Cα (PKCα) translocation was detected by subcellular fractionation and Western blot analysis. In addition, FGF-2-induced release of Smac from mitochondria to the cytoplasm was analyzed by Western blotting and immunofluorescence.FGF-2 reduced apoptosis induced by serum starvation and up-regulated survivin expression in H446 cells in a dosedependent and time-dependent manner, and inhibited caspase-3 activity. FGF-2 also inhibited the release of Smac from mitochondria to the cytoplasm induced by serum starvation and increased PKCα translocation from the cytoplasm to the cell membrane. In addition, PKC inhibitor inhibited the expression of survivin. FGF-2 up-regulates the expression of survivin protein in H446 cells and blocks the release of Smac from mitochondria to the cytoplasm. PKCα regulated FGF-2-induced survivin expression. Thus, survivin, Smac,and PKCα might play important roles in the inhibition of apoptosis by FGF-2 in human small cell lung cancer cells.

  14. Increased expression of fibroblast growth factor 13 in prostate cancer is associated with shortened time to biochemical recurrence after radical prostatectomy.

    Science.gov (United States)

    Yu, Lan; Toriseva, Mervi; Tuomala, Miikka; Seikkula, Heikki; Elo, Teresa; Tuomela, Johanna; Kallajoki, Markku; Mirtti, Tuomas; Taimen, Pekka; Boström, Peter J; Alanen, Kalle; Nurmi, Martti; Nees, Matthias; Härkönen, Pirkko

    2016-07-01

    Fibroblast growth factor homologous factors (FHFs) belong to the fibroblast growth factor (FGF) superfamily, which plays an important role in prostate cancer (PCa). Mining of public database suggests that FGF13 (FHF2) mRNA expression is altered in over 30% of PCa cases. This study examined the FGF13 expression pattern in human PCa specimens and evaluated its potential as a biomarker for patient outcome after radical prostatectomy (RP). Immunohistochemistry (IHC) showed that FGF13 was detectable in the majority of human PCa samples, and FGF13 IHC scores were higher in high-grade prostatic intraepithelial neoplasia, in primary PCa and in metastatic PCa than in benign prostatic tissue. There was a significant association between high cytoplasmic FGF13 staining and a risk of biochemical recurrence (BCR) after RP. This was also evident in the intermediate to high-risk patient groups. In contrast, positive nuclear FGF13 staining along with low cytoplasmic FGF13 group showed a decreased BCR risk. Multivariate regression analysis indicated that high cytoplasmic FGF13 staining was associated with BCR and that this could serve as an independent prognostic marker in PCa. Several PCa cell lines showed increased FGF13 expression at the mRNA and protein levels compared to the immortalized prostate epithelial cell line PNT1a. Analysis of co-labeled cells suggested a possible interaction of FGF13 with α-tubulin and the voltage-gated sodium channel proteins (NaV s/VGSCs). Our data indicate that, for PCa patients after RP, FGF13 serves as a potential novel prognostic marker that improves prediction of BCR-free survival, in particular if combined with other clinical parameters. PMID:26891277

  15. Hepatic Carcinoma—Associated Fibroblasts Promote an Adaptative Response in Colorectal Cancer Cells That Inhibit Proliferation and Apoptosis: Nonresistant Cells Die by Nonapoptotic Cell Death

    Directory of Open Access Journals (Sweden)

    Mireia Berdiel-Acer

    2011-10-01

    Full Text Available Carcinoma-associated fibroblasts (CAFs are important contributors of microenvironment in determining the tumor’s fate. This study aimed to compare the influence of liver microenvironment and primary tumor microenvironment on the behavior of colorectal carcinoma. Conditioned medium (CM from normal colonic fibroblasts (NCFs, CAFs from primary tumor (CAF-PT or liver metastasis (CAF-LM were obtained. We performed functional assays to test the influence of each CM on colorectal cell lines. Microarray and gene set enrichment analysis (GSEA were performed in DLD1 cells cultured in matched CM. In DLD1 cells, CAF-LM CM compared with CAF-PT CM and NCF led to a more aggressive phenotype, induced the features of an epithelial-to-mesenchymal transition more efficiently, and stimulated migration and invasion to a greater extent. Sustained stimulation with CAF-LM CM evoked a transient G2/M cell cycle arrest accompanied by a reduction of apoptosis, inhibition of proliferation, and decreased viability of SW1116, SW620, SW480, DLD1, HT-29, and Caco-2 cells and provoked nonapoptotic cell death in those cells carrying KRAS mutations. Cells resistant to CAF-LM CM completely changed their morphology in an extracellular signal-regulated protein kinase-dependent process and depicted an increased stemness capacity alongside the Wnt pathway stimulation. The transcriptomic profile of DLD1 cells treated with CAF-LM CM was associated with Wnt and mitogen-activated protein kinase pathways activation in GSEA. Therefore, the liver microenvironment induces more efficiently the aggressiveness of colorectal cancer cells than other matched microenvironments do but secondarily evokes cell death. Resistant cells displayed higher stemness capacity.

  16. Quantitative analysis using ELISA of vascular endothelial growth factor and basic fibroblast growth factor in human colorectal cancer, liver metastasis of colorectal cancer and hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Muriel Mathonnet; Bernard Descottes; Denis Valleix; Fran(c)ois Labrousse; Véronique Truffinet; Yves Denizot

    2006-01-01

    @@ TO THE EDITOR Angiogenesis consists of the sprouting of capillaries from pre-existing vessels[1]. It is well-known that tumor growth is angiogenesis-dependent. Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF)stimulated vascular endothelial cell proliferation and are involved in the neoplastic angiogenesis of several types of tumors including those of the intestinal tract[1-5].

  17. Survey of post-gamma-ray colony-forming ability, DNA metabolism and oncogene status in non-malignant fibroblast strains from cancer-prone families and individual cancer patients

    International Nuclear Information System (INIS)

    The in vitro radiobiological studies described here have focused on highly selected individuals comprising some of the most likely cases of predisposition to radiogenic cancer ascertained to date. Our results argue against the existence, within the general population, of quantitatively significant subgroups sensitive to the carcinogenic effects of ubiquitous low-level radiation. In fact, of the forty-six cancer-susceptible conditions examined, only four (i.e. members of the cancer-prone lineage in two kindreds and two isolated patients), exhibited abnormal cellular response to γ-rays in vitro. These findings indicate that in this unprecedented collection of high cancer risk conditions, the incidence of abnormal radiation cytotoxicity is only about two-fold above that found in a randomly selected group of age-matched healthy subjects (i.e, about 9% [4/46 conditions] versus about 5% [1/21 volunteers]). This interpretation of the data assumes, however, that the post-γ-ray CFA assay performed on cultured dermal fibroblasts is a reliable and sensitive indicator of the donor's susceptibility to develop radiogenic cancer, irrespective of the anatomical site or histological type of the tumour(s). (author)

  18. Cancer-associated fibroblasts promote non-small cell lung cancer cell invasion by upregulation of glucose-regulated protein 78 (GRP78) expression in an integrated bionic microfluidic device.

    Science.gov (United States)

    Yu, Ting; Guo, Zhe; Fan, Hui; Song, Jing; Liu, Yuanbin; Gao, Zhancheng; Wang, Qi

    2016-05-01

    The tumor microenvironment is comprised of cancer cells and various stromal cells and their respective cellular components. Cancer-associated fibroblasts (CAFs), a major part of the stromal cells, are a key determinant in tumor progression, while glucose-regulated protein (GRP)78 is overexpressed in many human cancers and is involved in tumor invasion and metastasis. This study developed a microfluidic-based three dimension (3D) co-culture device to mimic an in vitro tumor microenvironment in order to investigate tumor cell invasion in real-time. This bionic chip provided significant information regarding the role of GRP78, which may be stimulated by CAFs, to promote non-small cell lung cancer cell invasion in vitro. The data showed that CAF induced migration of NSCLC A549 and SPCA-1 cells in this three-dimensional invasion microdevice, which is confirmed by using the traditional Transwell system. Furthermore, CAF induced GRP78 expression in A549 and SPCA-1 cells to facilitate NSCLC cell migration and invasion, whereas knockdown of GRP78 expression blocked A549 and SPCA-1 cell migration and invasion capacity. In conclusion, these data indicated that CAFs might promote NSCLC cell invasion by up-regulation of GRP78 expression and this bionic chip microdevice is a robust platform to assess the interaction of cancer and stromal cells in tumor environment study. PMID:27016417

  19. Recombinogenic Telomeres in Diploid Sorex granarius (Soricidae, Eulipotyphla) Fibroblast Cells

    OpenAIRE

    Zhdanova, N. S.; Draskovic, I.; Minina, J. M.; Karamysheva, T. V.; Novo, C. L.; Liu, W.-Y.; Porreca, R. M.; Gibaud, A.; Zvereva, M.E.; Skvortsov, D. A.; Rubtsov, N.B.; Londoño-Vallejo, A

    2014-01-01

    The telomere structure in the Iberian shrew Sorex granarius is characterized by unique, striking features, with short arms of acrocentric chromosomes carrying extremely long telomeres (up to 300 kb) with interspersed ribosomal DNA (rDNA) repeat blocks. In this work, we investigated the telomere physiology of S. granarius fibroblast cells and found that telomere repeats are transcribed on both strands and that there is no telomere-dependent senescence mechanism. Although telomerase activit...

  20. Plant senescence and crop productivity

    DEFF Research Database (Denmark)

    Gregersen, Per L.; Culetic, Andrea; Boschian, Luca;

    2013-01-01

    Senescence is a developmental process which in annual crop plants overlaps with the reproductive phase. Senescence might reduce crop yield when it is induced prematurely under adverse environmental conditions. This review covers the role of senescence for the productivity of crop plants....... With the aim to enhance productivity, a number of functional stay-green cultivars have been selected by conventional breeding, in particular of sorghum and maize. In many cases, a positive correlation between leaf area duration and yield has been observed, although in a number of other cases, stay......-green cultivars do not display significant effects with regards to productivity. In several crops, the stay-green phenotype is observed to be associated with a higher drought resistance and a better performance under low nitrogen conditions. Among the approaches used to achieve stay-green phenotypes in transgenic...

  1. Predatory senescence in ageing wolves

    Science.gov (United States)

    MacNulty, D.R.; Smith, D.W.; Vucetich, J.A.; Mech, L.D.; Stahler, D.R.; Packer, C.

    2009-01-01

    It is well established that ageing handicaps the ability of prey to escape predators, yet surprisingly little is known about how ageing affects the ability of predators to catch prey. Research into long-lived predators has assumed that adults have uniform impacts on prey regardless of age. Here we use longitudinal data from repeated observations of individually-known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park to demonstrate that adult predatory performance declines with age and that an increasing ratio of senescent individuals in the wolf population depresses the rate of prey offtake. Because this ratio fluctuates independently of population size, predatory senescence may cause wolf populations of equal size but different age structure to have different impacts on prey populations. These findings suggest that predatory senescence is an important, though overlooked, factor affecting predator-prey dynamics. ?? 2009 Blackwell Publishing Ltd/CNRS.

  2. Immortalization of human fibroblasts transformed by origin-defective simian virus 40.

    OpenAIRE

    Neufeld, D S; Ripley, S; Henderson, A; Ozer, H L

    1987-01-01

    Simian virus 40 (SV40)-mediated transformation of human diploid fibroblasts has provided an effective experimental system for studies of both "senescence" in cell culture and carcinogenesis. Previous interpretations may have been complicated, however, by the semipermissive virus-cell interaction. In earlier studies, we previously demonstrated that the human diploid fibroblast line HS74 can be efficiently transformed by DNA from replication-defective mutants of SV40 containing a deletion in th...

  3. Selective insulin resistance in hepatocyte senescence

    International Nuclear Information System (INIS)

    Insulin resistance has been described in association with chronic liver disease for decades. Hepatocyte senescence has been demonstrated in chronic liver disease and as many as 80% of hepatocytes show a senescent phenotype in advanced liver disease. The aim of this study was to understand the role of hepatocyte senescence in the development of insulin resistance. Senescence was induced in HepG2 cells via oxidative stress. The insulin metabolic pathway was studied in control and senescent cells following insulin stimulation. GLUT2 and GLUT4 expressions were studied in HepG2 cells and human liver tissue. Further, GLUT2 and GLUT4 expressions were studied in three independent chronic liver disease cohorts. Signalling impairment distal to Akt in phosphorylation of AS160 and FoxO1 was evident in senescent HepG2 cells. Persistent nuclear localisation of FoxO1 was demonstrated in senescent cells despite insulin stimulation. Increased GLUT4 and decreased GLUT2 expressions were evident in senescent cells, human cirrhotic liver tissue and publically available liver disease datasets. Changes in GLUT expressions were associated with a poor clinical prognosis. In conclusion, selective insulin resistance is evident in senescent HepG2 cells and changes in GLUT expressions can be used as surrogate markers of hepatocyte senescence. - Highlights: • Senescent hepatocytes demonstrate selective insulin resistance. • GLUT changes act as markers of hepatocyte senescence and have prognostic value. • Study offers insight into long noticed intimacy of cirrhosis and insulin resistance

  4. Selective insulin resistance in hepatocyte senescence

    Energy Technology Data Exchange (ETDEWEB)

    Aravinthan, Aloysious [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Challis, Benjamin [Institute of Metabolic Sciences, University of Cambridge, Cambridge (United Kingdom); Shannon, Nicholas [Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Hoare, Matthew [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Heaney, Judith [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Foundation for Liver Research, Institute of Hepatology, London (United Kingdom); Alexander, Graeme J.M., E-mail: gja1000@doctors.org.uk [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom)

    2015-02-01

    Insulin resistance has been described in association with chronic liver disease for decades. Hepatocyte senescence has been demonstrated in chronic liver disease and as many as 80% of hepatocytes show a senescent phenotype in advanced liver disease. The aim of this study was to understand the role of hepatocyte senescence in the development of insulin resistance. Senescence was induced in HepG2 cells via oxidative stress. The insulin metabolic pathway was studied in control and senescent cells following insulin stimulation. GLUT2 and GLUT4 expressions were studied in HepG2 cells and human liver tissue. Further, GLUT2 and GLUT4 expressions were studied in three independent chronic liver disease cohorts. Signalling impairment distal to Akt in phosphorylation of AS160 and FoxO1 was evident in senescent HepG2 cells. Persistent nuclear localisation of FoxO1 was demonstrated in senescent cells despite insulin stimulation. Increased GLUT4 and decreased GLUT2 expressions were evident in senescent cells, human cirrhotic liver tissue and publically available liver disease datasets. Changes in GLUT expressions were associated with a poor clinical prognosis. In conclusion, selective insulin resistance is evident in senescent HepG2 cells and changes in GLUT expressions can be used as surrogate markers of hepatocyte senescence. - Highlights: • Senescent hepatocytes demonstrate selective insulin resistance. • GLUT changes act as markers of hepatocyte senescence and have prognostic value. • Study offers insight into long noticed intimacy of cirrhosis and insulin resistance.

  5. Transgenic plants with altered senescence characteristics

    Science.gov (United States)

    Amasino, Richard M.; Gan, Susheng; Noh, Yoo-Sun

    2002-03-19

    The identification of senescence-specific promoters from plants is described. Using information from the first senescence-specific promoter, SAG12 from Arabidopsis, other homologous promoters from another plant have been identified. Such promoters may be used to delay senescence in commercially important plants.

  6. Promising markers for the detection of premature senescence tumor cells induced by ionizing radiation: Cathepsin D and eukaryotic translation elongation factor 1

    International Nuclear Information System (INIS)

    Recently, it has been proved that induction of senescence could be a promising way of tumor treatment. Senescence was originally described in normal human cells undergoing a finite number of divisions before permanent growth arrest. It has now become regarded more broadly as a general biological program of terminal growth arrest. A variety of stresses such as ionizing radiation (IR), oxidative stress, oncogenic transformation, DNA damaging agents triggers stress-induced premature senescence, i.e. rapid and permanent cell growth arrest. Therefore, premature senescence is bona fide barrier to tumorigenesis and hallmark of premalignant tumors. However, there is lack of obvious markers for senescent tumor cells. To identify useful premature senescence markers for tumor cells, we monitored the changes of protein expression profile in IR-induced premature senescence MCF7 human breast cancer cells. We identified biomarkers which evidently changed their expression levels in ionizing radiation-induced senescenct tumor cells

  7. Senescence-related functional nuclear barrier by down-regulation of nucleo-cytoplasmic trafficking gene expression

    International Nuclear Information System (INIS)

    One of the characteristic natures of senescent cells is the hypo- or irresponsiveness not only to growth factors but also to apoptotic stress. In the present study, we confirmed the inhibition of nuclear translocation of activated p-ERK1/2 and NF-kB p50 in response to growth stimuli or LPS in the senescent human diploid fibroblasts. In order to elucidate the underlying mechanism for the senescence-associated hypo-responsiveness, we carried out the comparison study for gene expression profiles through microarray analysis. In consequence, we observed the vast reduction in expression of nucleo-cytoplasmic trafficking genes in senescent cells, when compared with those in young cells. Expression levels of several nucleoporins, karyopherin α, karyopherin β, Ran, and Ran-regulating factors were confirmed to be down-regulated in senescent HDFs by using RT-PCR and Western blot methods. Taken together, these data suggest the operation of certain senescence-associated functional nuclear barriers by down-regulation of the nucleo-cytoplasmic trafficking genes in the senescent cells.

  8. Aminolevulinic acid-based photodynamic therapy induces apoptosis of prematurely senescent fibroblasts induced by ultraviolet B stress%氨基酮戊酸光动力疗法诱导中波紫外线应激性衰老成纤维细胞发生凋亡

    Institute of Scientific and Technical Information of China (English)

    张丽超; 张海荣; 周炳荣; 骆丹; 马立文; 张家安; 王申; 易飞; Maya Valeska Gozali

    2015-01-01

    Objective To study the effect of aminolevulinic acid-based photodynamic therapy (ALA-PDT) on oxidative damage to and apoptosis of prematurely senescent fibroblasts induced by ultraviolet B stress (UVB-SIPS-FB).Methods Both normal fibroblasts and UVB-SIPS-FB were divided into 2-hour and 6-hour groups with the duration of incubation with ALA away from light being 2 and 6 hours respectively,and each group was divided into 7 subgroups:control subgroup receiving no treatment,ALA subgroup treated with ALA alone,red laser group treated with 100 J/cm2 red laser alone,3 ALA-PDT subgroups pretreated with ALA followed by red laser radiation at 25,50 and 100 J/cm2 respectively,NAC + ALA-PDT subgroup sequentially pretreated with ALA and NAC (5 mmol/L) followed by red laser radiation at 50 J/cm2.The wavelength and power density of red laser was 635 nm and 50 mW/cm2 respectively in this study.Fluorescence microscopy and flow cytometry were performed to determine the levels of reactive oxygen species (ROS) and mitochondrial membrane potentials (MMPs),and Hoechst staining and flow cytometry to detect cell apoptosis.Statistical analysis was carried out with the software SPSS 13.0 by one-way analysis of variance (ANOVA) and q test.Results The apoptosis rate of UVB-SIPS-FB was significantly higher in the 25-,50-,100-J/cm2 ALA-PDT subgroups (2-hour group:7.34% ± 0.87%,8.39% ± 1.16% and 17.03% ± 1.29% vs.3.81% ± 0.59%,F=102.70,P< 0.05;6-hour group:13.85% ± 1.71%,23.40% ± 2.14% and 41.02% ± 2.73% vs.5.09% ± 1.64%,F=106.00,P < 0.05) than in the control subgroups,but lower in the NAC + ALA-PDT subgroups (2-hour group:5.35% ± 0.58%,6-hour group:9.97% ± 3.23%,both P < 0.05) than in the 50-J/cm2 ALA-PDT subgroups.There was no significant difference in the apoptosis rate of UVB-SIPS-FB between the ALA subgroups or red laser subgroups and control subgroups.ALA-PDT subgroups showed significantly increased ROS level and MMP,and the degree of

  9. 99Tcm-N(NOEt2 Uptake Kinetics Difference among KMB17 Human Embryonic Lung Diploid Fibroblast and Different Human Lung Cancer Cells

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    Wei JIA

    2010-04-01

    Full Text Available Background and objective PET/CT imaging is expensive, so searching the tumor imaging agent for SPECT/CT is necessary. 99Tcm-N(NOEt2 [bis (N-ethoxy-N-ethyl dithiocarbamato nitrido99Tcm (V] can be uptaken by lung cancer cells and other cells alike. The aim of this study is to evaluate the distinctive value in lung tumor with 99Tcm-N(NOEt2, the difference in its uptake kinetics in human embryonic lung diploid fibroblasts KMB17 and several kinds of lung cancer cells lines. Methods Firstly, six different cell culture medium which contained YTMLC Gejiu human lung squamous carcinoma cell, SPC-A1 human lung adenocarcinoma cell, AGZY low metastatic human lung adenocarcinoma, 973 high metastatic human lung adenocarcinoma cell, GLC-82 Gejiu human lung adenocarcinoma cell, and KMB17 human embryonic lung diploid fibroblast, respectively with equal cell density of 1×106/mL and the same volume were prepared; secondly, the same radioactive dose of 99Tcm-N(NOEt2 was added into each sample and then 300 μL mixed sample was taken out respectively and cultured in 37 oC culture box; Finally, 5 min, 15 min, 30 min, 45 min, 60 min, 75 min, 90 min after cultivation, centrifuged each cultured sample and determined the intracellular radiocounts of each sample, calculated each cell sample’s uptake rate of 99Tcm-N(NOEt2 at different time. Results Statistical difference was found among six cell samples, and the uptake rate sequence from high to low is 973 and SPC-A1>YTMLC>GLC-82>AGZY>KMB17 respectively; furthermore, 30 min-45 min after culture, the uptake rate reached stability, and the 45 min uptake rate of each sample was higher than its 96.7% uptake peak. Conclusion Based on the results above mentioned, it is supposed that there are discriminative clinical value when using 99Tcm-N(NOEt2 as a tumor targeting imaging agent, and 30 min or so after injection may be the best imaging time in the early imaging stage.

  10. Relationship between residual radiation-induced DNA double-strand breaks in cultured fibroblasts and late radiation reactions: a comparison of training and validation cohorts of breast cancer patients

    International Nuclear Information System (INIS)

    Background and purpose: Using pulsed field gel electrophoresis (PFGE) a significant correlation was demonstrated between residual DNA double-strand breaks (dsbs) and the development of late radiation fibrosis in a group of 39 breast cancer patients studied retrospectively. This group formed a training cohort generating a hypothesis that there is a relationship between residual radiation-induced DNA dsbs in cultured fibroblasts and late radiotherapy reactions in breast cancer patients. The aim of this study was to retest and validate the hypothesis. Materials and methods: The study was retrospective. Skin biopsies were taken from a validation cohort of 50 breast cancer patients and PFGE was used to examine residual radiation-induced dsbs in cultured fibroblasts. Late morbidity was measured clinically as fibrosis and using the late effects on normal tissues scales that incorporate subjective, objective management and analytic data (LENT SOMA). Results: PFGE data were obtained for 49 biopsies. In the 49 patients there was no correlation between residual DNA damage and either fibrosis (r=-0.027, P=0.85) or LENT SOMA (r=-0.10, P=0.48) scores. There was no significant relationship between residual damage and fibrosis for the combined training and validation cohorts of 88 patients (r=0.20, P=0.063). Conclusions: This study did not validate the hypothesis that there is a relationship between fibroblast residual DNA damage and late morbidity in breast cancer patients. The PFGE assay on fibroblasts is not a suitable test of the degree of late radiation-induced fibrosis in the breast

  11. A study on genetic variants of Fibroblast growth factor receptor 2 (FGFR2 and the risk of breast cancer from North India.

    Directory of Open Access Journals (Sweden)

    Sarah Siddiqui

    Full Text Available Genome-Wide Association Studies (GWAS have identified Fibroblast growth factor receptor 2 (FGFR2 as a candidate gene for breast cancer with single nucleotide polymorphisms (SNPs located in intron 2 region as the susceptibility loci strongly associated with the risk. However, replicate studies have often failed to extrapolate the association to diverse ethnic regions. This hints towards the existing heterogeneity among different populations, arising due to differential linkage disequilibrium (LD structures and frequencies of SNPs within the associated regions of the genome. It is therefore important to revisit the previously linked candidates in varied population groups to unravel the extent of heterogeneity. In an attempt to investigate the role of FGFR2 polymorphisms in susceptibility to the risk of breast cancer among North Indian women, we genotyped rs2981582, rs1219648, rs2981578 and rs7895676 polymorphisms in 368 breast cancer patients and 484 healthy controls by Polymerase chain reaction-Restriction fragment length polymorphism (PCR-RFLP assay. We observed a statistically significant association with breast cancer risk for all the four genetic variants (P<0.05. In per-allele model for rs2981582, rs1219648, rs7895676 and in dominant model for rs2981578, association remained significant after bonferroni correction (P<0.0125. On performing stratified analysis, significant correlations with various clinicopathological as well as environmental and lifestyle characteristics were observed. It was evident that rs1219648 and rs2981578 interacted with exogenous hormone use and advanced clinical stage III (after Bonferroni correction, P<0.000694, respectively. Furthermore, combined analysis on these four loci revealed that compared to women with 0-1 risk loci, those with 2-4 risk loci had increased risk (OR = 1.645, 95%CI = 1.152-2.347, P = 0.006. In haplotype analysis, for rs2981578, rs2981582 and rs1219648, risk haplotype (GTG was

  12. Reversible Immortalization Enables Seamless Transdifferentiation of Primary Fibroblasts into Other Lineage Cells.

    Science.gov (United States)

    Xie, Fei; Gong, Kerui; Li, Ke; Zhang, Mingliang; Chang, Judy C; Jiang, Shizhong; Ye, Lin; Wang, Jiaming; Tan, Yuting; Kan, Yuet Wai

    2016-08-15

    Fibroblasts can be transdifferentiated directly into other somatic cells such as cardiomyocytes, hematopoietic cells, and neurons. An advantage of somatic cell differentiation without first generating induced pluripotent stem cells (iPSCs) is that it avoids contamination of the differentiated cells with residual iPSCs, which may cause teratoma. However, since primary fibroblasts from biopsy undergo senescence during repeated culture, it may be difficult to grow transdifferentiated cells in sufficient numbers for future therapeutic purposes. To circumvent this problem, we reversibly immortalized primary fibroblasts by using the piggyBac transposon to deliver the human telomerase reverse transcriptase (hTERT) gene hTERT plus SV40 Large T. Both approaches enabled fibroblasts to grow continuously without senescence, and neither caused teratoma formation in immunodeficient mice. However, fibroblasts immortalized with hTERT plus SV40 large T antigen accumulated chromosomal rearrangements, whereas fibroblasts immortalized with hTERT retained the normal karyotype. To transdifferentiate hTERT-immortalized fibroblasts into other somatic lineage cells, we transiently transfected them with episomal OCT4 and cultured them under neural cell growth condition with transposase to remove the transposon. Tripotent neural progenitor cells were seamlessly and efficiently generated. Thus, reversible immortalization of primary fibroblasts with hTERT will allow potential autologous cell-based therapeutics that bypass and simulate iPSC generation. PMID:27328768

  13. Dynamic Bcl-xL (S49) and (S62) Phosphorylation/Dephosphorylation during Mitosis Prevents Chromosome Instability and Aneuploidy in Normal Human Diploid Fibroblasts

    Science.gov (United States)

    Baruah, Prasamit Saurav; Beauchemin, Myriam; Hébert, Josée; Bertrand, Richard

    2016-01-01

    Bcl-xL proteins undergo dynamic phosphorylation/dephosphorylation on Ser49 and Ser62 residues during mitosis. The expression of Bcl-xL(S49A), (S62A) and dual (S49/62A) phosphorylation mutants in tumor cells lead to severe mitotic defects associated with multipolar spindle, chromosome lagging and bridging, and micro-, bi- and multi-nucleated cells. Because the above observations were made in tumor cells which already display genomic instability, we now address the question: will similar effects occur in normal human diploid cells? We studied normal human diploid BJ foreskin fibroblast cells expressing Bcl-xL (wild type), (S49A), (S49D), (S62A), (S62D) and the dual-site (S49/62A) and (S49/62D) mutants. Cells expressing S49 and/or S62 phosphorylation mutants showed reduced kinetics of cell population doubling. These effects on cell population doubling kinetics correlated with early outbreak of senescence with no impact on the cell death rate. Senescent cells displayed typical senescence-associated phenotypes including high-level of senescence-associated β-galactosidase activity, interleukin-6 (IL-6) secretion, tumor suppressor p53 and cyclin-dependent kinase inhibitor p21Waf1/Cip1 activation as well as γH2A.X-associated nuclear chromatin foci. Fluorescence in situ hybridization analysis and Giemsa-banded karyotypes revealed that the expression of Bcl-xL phosphorylation mutants in normal diploid BJ cells provoked chromosome instability and aneuploidy. These findings suggest that dynamic Bcl-xL(S49) and (S62) phosphorylation/dephosphorylation cycles are important in the maintenance of chromosome integrity during mitosis in normal cells. They could impact future strategies aiming to develop and identify compounds that could target not only the anti-apoptotic domain of Bcl-xL protein, but also its mitotic domain for cancer therapy. PMID:27398719

  14. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation

    Science.gov (United States)

    Zhang, Xurui; Ye, Caiyong; Sun, Fang; Wei, Wenjun; Hu, Burong; Wang, Jufang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92–1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. We observed less efficient repair when DNA damage was induced by heavy ions compared with X-rays and most of the irreparable damage was complex of single strand breaks and double strand breaks, while DNA damage induced by X-rays was mostly repaired in 24 hours and the remained damage was preferentially associated with telomeric DNA. Our results suggest that DNA damage induced by heavy ion is often complex and difficult to repair, thus presents as persistent DNA damage and pushes the cell into senescence. In contrast, persistent DNA damage induced by X-rays is preferentially associated with telomeric DNA and the telomere-favored persistent DNA damage contributes to X-rays induced cellular senescence. These findings provide new insight into the understanding of high relative biological effectiveness of heavy ions relevant to cancer therapy and space radiation research. PMID:27187621

  15. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation.

    Science.gov (United States)

    Zhang, Xurui; Ye, Caiyong; Sun, Fang; Wei, Wenjun; Hu, Burong; Wang, Jufang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92-1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. We observed less efficient repair when DNA damage was induced by heavy ions compared with X-rays and most of the irreparable damage was complex of single strand breaks and double strand breaks, while DNA damage induced by X-rays was mostly repaired in 24 hours and the remained damage was preferentially associated with telomeric DNA. Our results suggest that DNA damage induced by heavy ion is often complex and difficult to repair, thus presents as persistent DNA damage and pushes the cell into senescence. In contrast, persistent DNA damage induced by X-rays is preferentially associated with telomeric DNA and the telomere-favored persistent DNA damage contributes to X-rays induced cellular senescence. These findings provide new insight into the understanding of high relative biological effectiveness of heavy ions relevant to cancer therapy and space radiation research. PMID:27187621

  16. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation.

    Directory of Open Access Journals (Sweden)

    Xurui Zhang

    Full Text Available Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92-1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. We observed less efficient repair when DNA damage was induced by heavy ions compared with X-rays and most of the irreparable damage was complex of single strand breaks and double strand breaks, while DNA damage induced by X-rays was mostly repaired in 24 hours and the remained damage was preferentially associated with telomeric DNA. Our results suggest that DNA damage induced by heavy ion is often complex and difficult to repair, thus presents as persistent DNA damage and pushes the cell into senescence. In contrast, persistent DNA damage induced by X-rays is preferentially associated with telomeric DNA and the telomere-favored persistent DNA damage contributes to X-rays induced cellular senescence. These findings provide new insight into the understanding of high relative biological effectiveness of heavy ions relevant to cancer therapy and space radiation research.

  17. Cell surface response of chemically transformed, malignant mouse embryonal fibroblasts and human colon cancer cells to the maturation-promoting agent, N,N-dimethylformamide

    International Nuclear Information System (INIS)

    The lactoperoxidase/125I radioiodination procedure was used to probe the cell surface of normal, nontransformed AKR-2B mouse embryo fibroblasts and malignant, permanently methylcholanthrene-transformed AKR-2B (AKR-MCA) cells to establish the relationship between cell surface changes and transformation/differentiation in this call system. AKR-MCA cells displayed surface alterations secondary to N,N-dimethylformamide (DFM)-promoted differentiation. Growth of AKR-MCA cells in DMF virtually eliminated the 85,000 and 63,000 molecular weight surface proteins susceptible to radioiodination and increased surface material of ∼200,000 molecular weight. Thus, surface profiles of DFM-treated AKR-MCA cells were essentially identical to those of nontransformed AKR-2B cells. Experimentation was extended to a cultured human colon cancer cell line (HCT MOSER). HCT MOSER cells exposed to DMF manifested marked, reversible morphological and surface changes which occurred as a function of time of growth in DMF and DMF concentration. Interestingly, material reactive with anti-fibronectin was found on the surfaces and in the culture medium of DFM-treated HCT MOSER cells

  18. SM22{alpha}-induced activation of p16{sup INK4a}/retinoblastoma pathway promotes cellular senescence caused by a subclinical dose of {gamma}-radiation and doxorubicin in HepG2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Rim; Lee, Hee Min; Lee, So Yong; Kim, Eun Jin; Kim, Kug Chan [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Paik, Sang Gi [Department of Biology, School of Biosciences and Biotechnology, Chungnam National University, Daejeon (Korea, Republic of); Cho, Eun Wie, E-mail: ewcho@kribb.re.kr [Daejeon-KRIBB-FHCRC Cooperation Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Kim, In Gyu, E-mail: igkim@kaeri.re.kr [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-09-10

    Research highlights: {yields} SM22{alpha} overexpression in HepG2 cells leads cells to a growth arrest state, and the treatment of a subclinical dose of {gamma}-radiation or doxorubicin promotes cellular senescence. {yields} SM22{alpha} overexpression elevates p16{sup INK4a} followed by pRB activation, but there are no effects on p53/p21{sup WAF1/Cip1} pathway. {yields} SM22{alpha}-induced MT-1G activates p16{sup INK4a}/pRB pathway, which promotes cellular senescence by damaging agents. -- Abstract: Smooth muscle protein 22-alpha (SM22{alpha}) is known as a transformation- and shape change-sensitive actin cross-linking protein found in smooth muscle tissue and fibroblasts; however, its functional role remains uncertain. We reported previously that SM22{alpha} overexpression confers resistance against anti-cancer drugs or radiation via induction of metallothionein (MT) isozymes in HepG2 cells. In this study, we demonstrate that SM22{alpha} overexpression leads cells to a growth arrest state and promotes cellular senescence caused by treatment with a subclinical dose of {gamma}-radiation (0.05 and 0.1 Gy) or doxorubicin (0.01 and 0.05 {mu}g/ml), compared to control cells. Senescence growth arrest is known to be controlled by p53 phosphorylation/p21{sup WAF1/Cip1} induction or p16{sup INK4a}/retinoblastoma protein (pRB) activation. SM22{alpha} overexpression in HepG2 cells elevated p16{sup INK4a} followed by pRB activation, but did not activate the p53/p21{sup WAF1/Cip1} pathway. Moreover, MT-1G, which is induced by SM22{alpha} overexpression, was involved in the activation of the p16{sup INK4a}/pRB pathway, which led to a growth arrest state and promoted cellular senescence caused by damaging agents. Our findings provide the first demonstration that SM22{alpha} modulates cellular senescence caused by damaging agents via regulation of the p16{sup INK4a}/pRB pathway in HepG2 cells and that these effects of SM22{alpha} are partially mediated by MT-1G.

  19. Fibroblast Growth Factor 2—A Predictor of Outcome for Patients Irradiated for Stage II-III Non–Small-Cell Lung Cancer

    International Nuclear Information System (INIS)

    Purpose: The prognostic value of the tumor cell expression of the fibroblast growth factor 2 (FGF-2) in patients with non–small-cell lung cancer (NSCLC) is unclear. The present study investigated the effect of tumor cell expression of FGF-2 on the outcome of 60 patients irradiated for Stage II-III NSCLC. Methods and Materials: The effect of FGF-2 expression and 13 additional factors on locoregional control (LRC), metastasis-free survival (MFS), and overall survival (OS) were retrospectively evaluated. These additional factors included age, gender, Karnofsky performance status, histologic type, histologic grade, T and N category, American Joint Committee on Cancer stage, surgery, chemotherapy, pack-years, smoking during radiotherapy, and hemoglobin during radiotherapy. Locoregional failure was identified by endoscopy or computed tomography. Univariate analyses were performed with the Kaplan-Meier method and the Wilcoxon test and multivariate analyses with the Cox proportional hazard model. Results: On univariate analysis, improved LRC was associated with surgery (p = .017), greater hemoglobin levels (p = .036), and FGF-2 negativity (p <.001). On multivariate analysis of LRC, surgery (relative risk [RR], 2.44; p = .037), and FGF-2 expression (RR, 5.06; p <.001) maintained significance. On univariate analysis, improved MFS was associated with squamous cell carcinoma (p = .020), greater hemoglobin levels (p = .007), and FGF-2 negativity (p = .001). On multivariate analysis of MFS, the hemoglobin levels (RR, 2.65; p = .019) and FGF-2 expression (RR, 3.05; p = .004) were significant. On univariate analysis, improved OS was associated with a lower N category (p = .048), greater hemoglobin levels (p <.001), and FGF-2 negativity (p <.001). On multivariate analysis of OS, greater hemoglobin levels (RR, 4.62; p = .002) and FGF-2 expression (RR, 3.25; p = .002) maintained significance. Conclusions: Tumor cell expression of FGF-2 appeared to be an independent negative

  20. Irinotecan treatment and senescence failure promote the emergence of more transformed and invasive cells that depend on anti-apoptotic Mcl-1

    OpenAIRE

    Jonchère, Barbara; Vétillard, Alexandra; Toutain, Bertrand; Lam, David; Bernard, Anne Charlotte; Henry, Cécile; Trécesson, Sophie De Carné; Gamelin, Erick; Juin, Philippe; Guette, Catherine; Coqueret, Olivier

    2014-01-01

    Induction of senescence by chemotherapy was initially characterized as a suppressive response that prevents tumor cell proliferation. However, in response to treatment, it is not really known how cells can survive senescence and how irreversible this pathway is. In this study, we analyzed cell escape in response to irinotecan, a first line treatment used in colorectal cancer that induced senescence. We detected subpopulations of cells that adapted to chemotherapy and resumed proliferation. Su...

  1. Stress-induced premature senescence (SIPS). Influence of SIPS on radiotherapy

    International Nuclear Information System (INIS)

    Replicative senescence is a fundamental feature in normal human diploid cells and results from dysfunctional telomeres at the Hayflick cell division limit. Ionizing radiation (IR) prematurely induces the same phenotypes as replicative senescence prior to the Hayflick limit. This process is known as stress-induced premature senescence (SIPS). Since the cell cycle is irreversibly arrested in SIPS-induced cells, even if they are stimulated by various growth factors, it is thought that SIPS is a form of cell death, irreversibly eliminating replicating cells. IR-induced-focus formation of DNA repair proteins, a marker of DNA damage, is detected in SIPS as well as replicative senescent cells. Furthermore, both processes persistently induce cell cycle checkpoint mechanisms, indicating DNA damage created by ionizing radiation induces SIPS in normal cells, possibly by the same mechanisms as those occurring in replicative senescence. Interestingly, IR induces SIPS not only in normal cells, but also in tumor cells. Due to the expression of telomerase in tumor cells, telomere-dependent replicative senescence does not occur. However, SIPS is induced under certain conditions after IR exposure. Thus, cell death triggered by IR can be attributed to apoptosis or SIPS in tumor cells. However, metabolic function remains intact in SIPS-induced cancer cells, and recent studies show that senescence eliminate cells undergoing SIPS secrete various kinds of factors outside the cell, changing the microenvironment. Evidence using co-culture systems containing normal senescent stromal cells and epithelial tumor cells show that factors secreted from senescent stroma cells promote the growth of tumor epithelial cells both in vitro and in vivo. Thus, regulation of factors secreted from SIPS-induced stromal cells, as well as tumor cells, may affect radiotherapy. (author)

  2. A novel requirement for Janus kinases as mediators of drug resistance induced by fibroblast growth factor-2 in human cancer cells.

    Directory of Open Access Journals (Sweden)

    Catarina R Carmo

    Full Text Available The development of resistance to chemotherapy is a major cause of cancer-related death. Elucidating the mechanisms of drug resistance should thus lead to novel therapeutic strategies. Fibroblast growth factor (FGF-2 signaling induces the assembly of a multi-protein complex that provides tumor cells with the molecular machinery necessary for drug resistance. This complex, which involves protein kinase C (PKC ε, v-raf murine sarcoma viral oncogene homolog B1 (B-RAF and p70 S6 kinase β (S6K2, enhances the selective translation of anti-apoptotic proteins such as B-cell leukaemia/lymphoma-2 (BCL-2 and inhibitors of apoptosis protein (IAP family members and these are able to protect multiple cancer cell types from chemotherapy-induced cell death. The Janus kinases (JAKs are most noted for their critical roles in mediating cytokine signaling and immune responses. Here, we show that JAKs have novel functions that support their consideration as new targets in therapies aimed at reducing drug resistance. As an example, we show that the Janus kinase TYK2 is phosphorylated downstream of FGF-2 signaling and required for the full phosphorylation of extracellular signal-regulated kinase (ERK 1/2. Moreover, TYK2 is necessary for the induction of key anti-apoptotic proteins, such as BCL-2 and myeloid cell leukemia sequence (MCL 1, and for the promotion of cell survival upon FGF-2. Silencing JAK1, JAK2 or TYK2 using RNA interference (RNAi inhibits FGF2-mediated proliferation and results in the sensitization of tumor cells to chemotherapy-induced killing. These effects are independent of activation of signal transducer and activator of transcription (STAT 1, STAT3 and STAT5A/B, the normal targets of JAK signaling. Instead, TYK2 associates with the other kinases previously implicated in FGF-2-mediated drug resistance. In light of these findings we hypothesize that TYK2 and other JAKs are important modulators of FGF-2-driven cell survival and that inhibitors of

  3. Biomarkers of replicative senescence revisited

    DEFF Research Database (Denmark)

    Nehlin, Jan

    2016-01-01

    of telomere length and associated damage, and the accompanying changes that take place elicit signals that have an impact on a number of molecules and downstream events. Precise measurements of replicative senescence biomarkers in biological samples from individuals could be clinically associated...... with their chronological age and present health status, help define their current rate of aging and contribute to establish personalized therapy plans to reduce, counteract or even avoid the appearance of aging biomarkers....

  4. The oxidative hypothesis of senescence

    Directory of Open Access Journals (Sweden)

    Gilca M

    2007-01-01

    Full Text Available The oxidative hypothesis of senescence, since its origin in 1956, has garnered significant evidence and growing support among scientists for the notion that free radicals play an important role in ageing, either as "damaging" molecules or as signaling molecules. Age-increasing oxidative injuries induced by free radicals, higher susceptibility to oxidative stress in short-lived organisms, genetic manipulations that alter both oxidative resistance and longevity and the anti-ageing effect of caloric restriction and intermittent fasting are a few examples of accepted scientific facts that support the oxidative theory of senescence. Though not completely understood due to the complex "network" of redox regulatory systems, the implication of oxidative stress in the ageing process is now well documented. Moreover, it is compatible with other current ageing theories (e.g., those implicating the mitochondrial damage/mitochondrial-lysosomal axis, stress-induced premature senescence, biological "garbage" accumulation, etc. This review is intended to summarize and critically discuss the redox mechanisms involved during the ageing process: sources of oxidant agents in ageing (mitochondrial -electron transport chain, nitric oxide synthase reaction- and non-mitochondrial- Fenton reaction, microsomal cytochrome P450 enzymes, peroxisomal β -oxidation and respiratory burst of phagocytic cells, antioxidant changes in ageing (enzymatic- superoxide dismutase, glutathione-reductase, glutathion peroxidase, catalase- and non-enzymatic glutathione, ascorbate, urate, bilirubine, melatonin, tocopherols, carotenoids, ubiquinol, alteration of oxidative damage repairing mechanisms and the role of free radicals as signaling molecules in ageing.

  5. A higher oxidative status accelerates senescence and aggravates age-dependent disorders in SAMP strains of mice.

    Science.gov (United States)

    Hosokawa, Masanori

    2002-11-01

    The SAM strain of mice is actually a group of related inbred strains consisting of series of SAMP (accelerated senescence-prone, short-lived) and SAMR (accelerated senescence-resistant, longer-lived) strains. Comparing with the SAMR strains, the SAMP strains of mice show a more accelerated senescence process, shorter lifespan, and an earlier onset and more rapid progress of age-associated pathological phenotypes similar to several geriatric disorders observed in humans, including senile osteoporosis, degenerative joint disease, age-related deficits in learning and memory, olfactory bulb and forebrain atrophy, presbycusis and retinal atrophy, senile amyloidosis, immunosenescence, senile lungs, and diffuse medial thickening of the aorta. The higher oxidative stress observed in the SAMP strains of mice are partly caused by mitochondrial dysfunction, and may be one cause of the senescence acceleration and age-dependent alterations in cell structure and function, including neuronal cell degeneration. This senescence acceleration is also observed during senescence/crisis in cultures of isolated fibroblast-like cells from SAMP strains of mice, and was associated with a hyperoxidative status. These observations suggest that the SAM strains are useful tools in the attempt to understand the mechanisms of age-dependent degeneration of cells and tissues, and their aggravation, and to develop clinical interventions. PMID:12470893

  6. Forging a signature of in vivo senescence.

    Science.gov (United States)

    Sharpless, Norman E; Sherr, Charles J

    2015-07-01

    'Cellular senescence', a term originally defining the characteristics of cultured cells that exceed their replicative limit, has been broadened to describe durable states of proliferative arrest induced by disparate stress factors. Proposed relationships between cellular senescence, tumour suppression, loss of tissue regenerative capacity and ageing suffer from lack of uniform definition and consistently applied criteria. Here, we highlight caveats in interpreting the importance of suboptimal senescence-associated biomarkers, expressed either alone or in combination. We advocate that more-specific descriptors be substituted for the now broadly applied umbrella term 'senescence' in defining the suite of diverse physiological responses to cellular stress. PMID:26105537

  7. Reprogramming of Fibroblasts From Older Women With Pelvic Floor Disorders Alters Cellular Behavior Associated With Donor Age

    OpenAIRE

    Wen, Yan; Wani, Prachi; Zhou, Lu; Baer, Tom; Phadnis, Smruti Madan; Reijo Pera, Renee A.; Chen, Bertha

    2013-01-01

    The effect of donor age on induced pluripotent stem cell (iPSC) lines and on the cells redifferentiated from these iPSCs was examined. iPSCs were derived from vaginal fibroblasts from women with pelvic organ prolapse. Donor age did not appear to affect reprogramming and cell mitotic activity in fibroblasts redifferentiated from iPSCs, and donor age differences were not observed in the iPSCs using standard senescence markers.

  8. Phenylbutyric acid induces the cellular senescence through an Akt/p21{sup WAF1} signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hag Dong [Laboratory of Biochemistry, School of Life Sciences and Biotechnology, and BioInstitute, Korea University, Seoul 136-701 (Korea, Republic of); Jang, Chang-Young [Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women' s University, Seoul 140-742 (Korea, Republic of); Choe, Jeong Min [Laboratory of Biochemistry, School of Life Sciences and Biotechnology, and BioInstitute, Korea University, Seoul 136-701 (Korea, Republic of); Department of Biochemistry, Korea University College of Medicine, Seoul 136-705 (Korea, Republic of); Korean Institute of Molecular Medicine and Nutrition, Seoul 136-705 (Korea, Republic of); Sohn, Jeongwon, E-mail: biojs@korea.ac.kr [Department of Biochemistry, Korea University College of Medicine, Seoul 136-705 (Korea, Republic of); Korean Institute of Molecular Medicine and Nutrition, Seoul 136-705 (Korea, Republic of); Kim, Joon, E-mail: joonkim@korea.ac.kr [Laboratory of Biochemistry, School of Life Sciences and Biotechnology, and BioInstitute, Korea University, Seoul 136-701 (Korea, Republic of)

    2012-06-01

    Highlights: Black-Right-Pointing-Pointer Phenylbutyric acid induces cellular senescence. Black-Right-Pointing-Pointer Phenylbutyric acid activates Akt kinase. Black-Right-Pointing-Pointer The knockdown of PERK also can induce cellular senescence. Black-Right-Pointing-Pointer Akt/p21{sup WAF1} pathway activates in PERK knockdown induced cellular senescence. -- Abstract: It has been well known that three sentinel proteins - PERK, ATF6 and IRE1 - initiate the unfolded protein response (UPR) in the presence of misfolded or unfolded proteins in the ER. Recent studies have demonstrated that upregulation of UPR in cancer cells is required to survive and proliferate. Here, we showed that long exposure to 4-phenylbutyric acid (PBA), a chemical chaperone that can reduce retention of unfolded and misfolded proteins in ER, induced cellular senescence in cancer cells such as MCF7 and HT1080. In addition, we found that treatment with PBA activates Akt, which results in p21{sup WAF1} induction. Interestingly, the depletion of PERK but not ATF6 and IRE1 also induces cellular senescence, which was rescued by additional depletion of Akt. This suggests that Akt pathway is downstream of PERK in PBA induced cellular senescence. Taken together, these results show that PBA induces cellular senescence via activation of the Akt/p21{sup WAF1} pathway by PERK inhibition.

  9. Senescence in Human Mesenchymal Stem Cells: Functional Changes and Implications in Stem Cell-Based Therapy

    Science.gov (United States)

    Turinetto, Valentina; Vitale, Emanuela; Giachino, Claudia

    2016-01-01

    Regenerative medicine is extensively interested in developing cell therapies using mesenchymal stem cells (MSCs), with applications to several aging-associated diseases. For successful therapies, a substantial number of cells are needed, requiring extensive ex vivo cell expansion. However, MSC proliferation is limited and it is quite likely that long-term culture evokes continuous changes in MSCs. Therefore, a substantial proportion of cells may undergo senescence. In the present review, we will first present the phenotypic characterization of senescent human MSCs (hMSCs) and their possible consequent functional alterations. The accumulation of oxidative stress and dysregulation of key differentiation regulatory factors determine decreased differentiation potential of senescent hMSCs. Senescent hMSCs also show a marked impairment in their migratory and homing ability. Finally, many factors present in the secretome of senescent hMSCs are able to exacerbate the inflammatory response at a systemic level, decreasing the immune modulation activity of hMSCs and promoting either proliferation or migration of cancer cells. Considering the deleterious effects that these changes could evoke, it would appear of primary importance to monitor the occurrence of senescent phenotype in clinically expanded hMSCs and to evaluate possible ways to prevent in vitro MSC senescence. An updated critical presentation of the possible strategies for in vitro senescence monitoring and prevention constitutes the second part of this review. Understanding the mechanisms that drive toward hMSC growth arrest and evaluating how to counteract these for preserving a functional stem cell pool is of fundamental importance for the development of efficient cell-based therapeutic approaches. PMID:27447618

  10. Re-expression of HPV16 E2 in SiHa (human cervical cancer) cells potentiates NF-κB activation induced by TNF-α concurrently increasing senescence and survival.

    Science.gov (United States)

    Prabhavathy, Devan; Subramanian, Chandrasekaran Karthik; Karunagaran, Devarajan

    2015-01-01

    Re-expression of E2 in human papillomavirus (HPV) transformed tumour cells can induce apoptosis; however, some evidences also attribute an important role to E2 in sustaining tumorigenesis. In the present paper, we studied the effects of tumour necrosis factor (TNF)-α-mediated NF-κB (nuclear factor kappa-light-chain-enhancer of activated B-cells) activation on E2-induced senescence in HPV16-integrated SiHa cells. The results show that E2 inhibits endogenous E6 gene expression and sensitizes SiHa cells to TNF-α-induced NF-κB activation. Under this condition there was an increase in the expression of senescent proteins p53, p21, p27 and p16 and senescence-associated (SA)-β-galactosidase activity indicating that TNF-α augments E2-mediated senescence. Re-expression of E2 expression with TNF-α treatment resulted in an increase in the expression of anti-apoptotic Bcl2 (B-cell lymphoma 2) protein and other pro-survival genes like cyclin D1 (cyc D1), survivin and hTERT (human telomerase reverse transcriptase). Concomitantly, E2 + TNF-α combination increased the survival of SiHa cells by positive changes in viability, proliferation and colony formation. E2-induced apoptotic tendency shifted towards senescence in presence of TNF-α by arresting the cells at both G0/G1 and G2/M phases, thus enhancing cell survival. Another observation in the present study is the significant up-regulation of key senescence messaging factors regulated by NF-κB namely interleukin (IL)-6, IL-8, high-mobility group protein A (HMGA)1 and B (HMGB)1 in E2-transfected cells treated with TNF-α. Our data provide a mechanistic basis and a new insight for the role of TNF-α and E2 in linking cellular senescence, tumorigenesis and HPV re-infection. PMID:25572145

  11. Piperlongumine Suppresses Proliferation of Human Oral Squamous Cell Carcinoma through Cell Cycle Arrest, Apoptosis and Senescence.

    Science.gov (United States)

    Chen, San-Yuan; Liu, Geng-Hung; Chao, Wen-Ying; Shi, Chung-Sheng; Lin, Ching-Yen; Lim, Yun-Ping; Lu, Chieh-Hsiang; Lai, Peng-Yeh; Chen, Hau-Ren; Lee, Ying-Ray

    2016-01-01

    Oral squamous cell carcinoma (OSCC), an aggressive cancer originating in the oral cavity, is one of the leading causes of cancer deaths in males worldwide. This study investigated the antitumor activity and mechanisms of piperlongumine (PL), a natural compound isolated from Piper longum L., in human OSCC cells. The effects of PL on cell proliferation, the cell cycle, apoptosis, senescence and reactive oxygen species (ROS) levels in human OSCC cells were investigated. PL effectively inhibited cell growth, caused cell cycle arrest and induced apoptosis and senescence in OSCC cells. Moreover, PL-mediated anti-human OSCC behavior was inhibited by an ROS scavenger N-acetyl-l-cysteine (NAC) treatment, suggesting that regulation of ROS was involved in the mechanism of the anticancer activity of PL. These findings suggest that PL suppresses tumor growth by regulating the cell cycle and inducing apoptosis and senescence and is a potential chemotherapy agent for human OSCC cells. PMID:27120594

  12. Piperlongumine Suppresses Proliferation of Human Oral Squamous Cell Carcinoma through Cell Cycle Arrest, Apoptosis and Senescence

    Directory of Open Access Journals (Sweden)

    San-Yuan Chen

    2016-04-01

    Full Text Available Oral squamous cell carcinoma (OSCC, an aggressive cancer originating in the oral cavity, is one of the leading causes of cancer deaths in males worldwide. This study investigated the antitumor activity and mechanisms of piperlongumine (PL, a natural compound isolated from Piper longum L., in human OSCC cells. The effects of PL on cell proliferation, the cell cycle, apoptosis, senescence and reactive oxygen species (ROS levels in human OSCC cells were investigated. PL effectively inhibited cell growth, caused cell cycle arrest and induced apoptosis and senescence in OSCC cells. Moreover, PL-mediated anti-human OSCC behavior was inhibited by an ROS scavenger N-acetyl-l-cysteine (NAC treatment, suggesting that regulation of ROS was involved in the mechanism of the anticancer activity of PL. These findings suggest that PL suppresses tumor growth by regulating the cell cycle and inducing apoptosis and senescence and is a potential chemotherapy agent for human OSCC cells.

  13. Radiation induced chromosome instability in human fibroblasts

    International Nuclear Information System (INIS)

    Evidence has been arising that some biological effects can manifest many cell divisions after irradiation. We have demonstrated that de novo chromosome instability can be detected 10- 15 mean population doubling after heavy ion irradiations. This chromosome instability is characterized by end to end fusions between specific chromosomes. The specificity of the instability may differ from one donor to another but for the same donor, the same instability should be observed after irradiation, during the senescence process and after SV40 transfection (before crisis). In irradiated primary culture fibroblasts, the expression of the delayed chromosomal instability lasts for several cell divisions without inducing cell death. Several rounds of fusions- breakage-fusions can be performed and unbalanced clones emerge (gain or loss of chromosomes with the shorter telomeres would become unstable first.. The difference in the chromosomal instability among donors could be due to a polymorphism in telomere lengths. This could induce large variation in long term response to irradiation among individuals. (author)

  14. Petal Senescence: New Concepts for Ageing Cells

    NARCIS (Netherlands)

    Woltering, E.J.; Doorn, van W.G.

    2009-01-01

    Senescence in flower petals can be regarded as a form of programmed cell death (PCD), being a process where cells or tissues are broken down in an orderly and predictable manner, whereby nutrients are re-used by other cells, tissues or plant parts. The process of petal senescence shows many similari

  15. Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Phadke, Manali; Krynetskaia, Natalia [Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Mishra, Anurag [Jayne Haines Center for Pharmacogenomics, Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Krynetskiy, Evgeny, E-mail: ekrynets@temple.edu [Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Jayne Haines Center for Pharmacogenomics, Temple University School of Pharmacy, Philadelphia, PA 19140 (United States)

    2011-07-29

    Highlights: {yields} We examined the effect of glyceraldehyde 3-phosphate (GAPDH) depletion on proliferation of human carcinoma A549 cells. {yields} GAPDH depletion induces accelerated senescence in tumor cells via AMPK network, in the absence of DNA damage. {yields} Metabolic and genetic rescue experiments indicate that GAPDH has regulatory functions linking energy metabolism and cell cycle. {yields} Induction of senescence in LKB1-deficient lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation. -- Abstract: Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-{beta}-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of {alpha} subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

  16. Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

    International Nuclear Information System (INIS)

    Highlights: → We examined the effect of glyceraldehyde 3-phosphate (GAPDH) depletion on proliferation of human carcinoma A549 cells. → GAPDH depletion induces accelerated senescence in tumor cells via AMPK network, in the absence of DNA damage. → Metabolic and genetic rescue experiments indicate that GAPDH has regulatory functions linking energy metabolism and cell cycle. → Induction of senescence in LKB1-deficient lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation. -- Abstract: Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-β-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of α subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

  17. Possible Roles of Strigolactones during Leaf Senescence

    Directory of Open Access Journals (Sweden)

    Yusuke Yamada

    2015-09-01

    Full Text Available Leaf senescence is a complicated developmental process that involves degenerative changes and nutrient recycling. The progress of leaf senescence is controlled by various environmental cues and plant hormones, including ethylene, jasmonic acid, salicylic acid, abscisic acid, cytokinins, and strigolactones. The production of strigolactones is induced in response to nitrogen and phosphorous deficiency. Strigolactones also accelerate leaf senescence and regulate shoot branching and root architecture. Leaf senescence is actively promoted in a nutrient-poor soil environment, and nutrients are transported from old leaves to young tissues and seeds. Strigolactones might act as important signals in response to nutrient levels in the rhizosphere. In this review, we discuss the possible roles of strigolactones during leaf senescence.

  18. Expression of Senescence-Associated microRNAs and Target Genes in Cellular Aging and Modulation by Tocotrienol-Rich Fraction

    Directory of Open Access Journals (Sweden)

    Sharon Gwee Sian Khee

    2014-01-01

    Full Text Available Emerging evidences highlight the implication of microRNAs as a posttranscriptional regulator in aging. Several senescence-associated microRNAs (SA-miRNAs are found to be differentially expressed during cellular senescence. However, the role of dietary compounds on SA-miRNAs remains elusive. This study aimed to elucidate the modulatory role of tocotrienol-rich fraction (TRF on SA-miRNAs (miR-20a, miR-24, miR-34a, miR-106a, and miR-449a and established target genes of miR-34a (CCND1, CDK4, and SIRT1 during replicative senescence of human diploid fibroblasts (HDFs. Primary cultures of HDFs at young and senescent were incubated with TRF at 0.5 mg/mL. Taqman microRNA assay showed significant upregulation of miR-24 and miR-34a and downregulation of miR-20a and miR-449a in senescent HDFs (P<0.05. TRF reduced miR-34a expression in senescent HDFs and increased miR-20a expression in young HDFs and increased miR-449a expression in both young and senescent HDFs. Our results also demonstrated that ectopic expression of miR-34a reduced the expression of CDK4 significantly (P<0.05. TRF inhibited miR-34a expression thus relieved its inhibition on CDK4 gene expression. No significant change was observed on the expression of CCND1, SIRT1, and miR-34a upstream transcriptional regulator, TP53. In conclusion tocotrienol-rich fraction prevented cellular senescence of human diploid fibroblasts via modulation of SA-miRNAs and target genes expression.

  19. Fibroblasts in fibrosis: novel roles and mediators

    Directory of Open Access Journals (Sweden)

    Ryan Thomas Kendall

    2014-05-01

    Full Text Available Fibroblasts are the most common cell type of the connective tissues found throughout the body and the principal source of the extensive extracellular matrix (ECM characteristic of these tissues. They are also the central mediators of the pathological fibrotic accumulation of ECM and the cellular proliferation and differentiation that occurs in response to prolonged tissue injury and chronic inflammation. The transformation of the fibroblast cell lineage involves classical developmental signaling programs and includes a surprisingly diverse range of precursor cell types—most notably, myofibroblasts that are the apex of the fibrotic phenotype. Myofibroblasts display exaggerated ECM production; constitutively secrete and are hypersensitive to chemical signals such as cytokines, chemokines, and growth factors; and are endowed with a contractile apparatus allowing them to manipulate the ECM fibers physically to close open wounds. In addition to ECM production, fibroblasts have multiple concomitant biological roles, such as in wound healing, inflammation, and angiogenesis, which are each interwoven with the process of fibrosis. We now recognize many common fibroblast-related features across various physiological and pathological protracted processes. Indeed, a new appreciation has emerged for the role of noncancerous fibroblast interactions with tumors in cancer progression. Although the predominant current clinical treatments of fibrosis involve nonspecific immunosuppressive and anti-proliferative drugs, a variety of potential therapies under investigation specifically target fibroblast biology.

  20. Simvastatin rises reactive oxygen species levels and induces senescence in human melanoma cells by activation of p53/p21 pathway

    International Nuclear Information System (INIS)

    Recent studies demonstrated that simvastatin has antitumor properties in several types of cancer cells, mainly by inducing apoptosis and inhibiting growth. The arrest of proliferation is a feature of cellular senescence; however, the occurrence of senescence in melanoma cells upon simvastatin treatment has not been investigated until now. Our results demonstrated that exposure of human metastatic melanoma cells (WM9) to simvastatin induces a senescent phenotype, characterized by G1 arrest, positive staining for senescence-associated β-galactosidase assay, and morphological changes. Also, the main pathways leading to cell senescence were examined in simvastatin-treated human melanoma cells, and the expression levels of phospho-p53 and p21 were upregulated by simvastatin, suggesting that cell cycle regulators and DNA damage pathways are involved in the onset of senescence. Since simvastatin can act as a pro-oxidant agent, and oxidative stress may be related to senescence, we measured the intracellular ROS levels in WM9 cells upon simvastatin treatment. Interestingly, we found an increased amount of intracellular ROS in these cells, which was accompanied by elevated expression of catalase and peroxiredoxin-1. Collectively, our results demonstrated that simvastatin can induce senescence in human melanoma cells by activation of p53/p21 pathway, and that oxidative stress may be related to this process. - Highlights: • Lower concentrations of simvastatin can induce senescent phenotype in melanoma cells. • Simvastatin induces senescence in human melanoma cells via p53/p21 pathway. • Senescent phenotype is related with increased intracellular ROS. • Partial detoxification of ROS by catalase/peroxiredoxin-1 could lead cells to senescence rather than apoptosis

  1. Simvastatin rises reactive oxygen species levels and induces senescence in human melanoma cells by activation of p53/p21 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Guterres, Fernanda Augusta de Lima Barbosa; Martinez, Glaucia Regina; Rocha, Maria Eliane Merlin; Winnischofer, Sheila Maria Brochado, E-mail: sheilambw@ufpr.br

    2013-11-15

    Recent studies demonstrated that simvastatin has antitumor properties in several types of cancer cells, mainly by inducing apoptosis and inhibiting growth. The arrest of proliferation is a feature of cellular senescence; however, the occurrence of senescence in melanoma cells upon simvastatin treatment has not been investigated until now. Our results demonstrated that exposure of human metastatic melanoma cells (WM9) to simvastatin induces a senescent phenotype, characterized by G1 arrest, positive staining for senescence-associated β-galactosidase assay, and morphological changes. Also, the main pathways leading to cell senescence were examined in simvastatin-treated human melanoma cells, and the expression levels of phospho-p53 and p21 were upregulated by simvastatin, suggesting that cell cycle regulators and DNA damage pathways are involved in the onset of senescence. Since simvastatin can act as a pro-oxidant agent, and oxidative stress may be related to senescence, we measured the intracellular ROS levels in WM9 cells upon simvastatin treatment. Interestingly, we found an increased amount of intracellular ROS in these cells, which was accompanied by elevated expression of catalase and peroxiredoxin-1. Collectively, our results demonstrated that simvastatin can induce senescence in human melanoma cells by activation of p53/p21 pathway, and that oxidative stress may be related to this process. - Highlights: • Lower concentrations of simvastatin can induce senescent phenotype in melanoma cells. • Simvastatin induces senescence in human melanoma cells via p53/p21 pathway. • Senescent phenotype is related with increased intracellular ROS. • Partial detoxification of ROS by catalase/peroxiredoxin-1 could lead cells to senescence rather than apoptosis.

  2. Inference of Target Gene Regulation via miRNAs during Cell Senescence by Using the MiRaGE Server.

    Science.gov (United States)

    Taguchi, Y-H

    2012-08-01

    miRNAs have recently been shown to play a key role in cell senescence, by downregulating target genes. Thus, inference of those miRNAs that critically downregulate target genes is important. However, inference of target gene regulation by miRNAs is difficult and is often achieved simply by investigating significant upregulation during cell senescence. Here, we inferred the regulation of target genes by miRNAs, using the recently developed MiRaGE server, together with the change in miRNA expression during fibroblast IMR90 cell senescence. We revealed that the simultaneous consideration of 2 criteria, the up(down)regulation and the down(up) regulatiion of target genes, yields more feasible miRNA, i.e., those that are most frequently reported to be down/upregulated and/or to possess biological backgrounds that induce cell senescence. Thus, when analyzing miRNAs that critically contribute to cell senescence, it is important to consider the level of target gene regulation, simultaneously with the change in miRNA expression. PMID:23185711

  3. Characterization of a novel positive transcription regulatory element that differentially regulates the alpha-2-macroglobulin gene in replicative senescence.

    Science.gov (United States)

    Li, Renzhong; Ma, Liwei; Huang, Yu; Zhang, Zongyu; Tong, Tanjun

    2011-12-01

    Alpha-2-macroglobulin (α2M), a protease inhibitor, is implicated in Alzheimer's disease, atherosclerosis, and other age-related diseases. The elevated level of α2M mRNA has been described in replicative senescence and it could be used as a biomarker of the aging cells. However, the mechanism responsible for the up-regulation of its expression is still unclear. This report identified a novel transcriptional regulatory element, the α2M transcription enhancement element (ATEE), within the α2M promoter. This element differentially activates α2M expression in senescent versus young fibroblasts. Electrophoretic mobility shift assays revealed abundant complexes in senescent cell nuclear extracts compared with young cell nuclear extracts. The DNase I footprint revealed the protein-binding core sequence through which the protein binds the ATEE. Mutation within ATEE selectively abolished α2M promoter activity in senescent (but not young) cells. These results indicated the ATEE, as a positive transcription regulatory element, contributes to the up-regulation of α2M during replicative senescence. PMID:21541797

  4. The fibroblast growth factor-2 (F.G.F.-2) expression predicts the tumoral response and the local of non at small cells bronchi cancers after chemoradiotherapy

    International Nuclear Information System (INIS)

    The tumoral expression of the fibroblast growth factor-2 is correlated with a bad response to chemotherapy and a strong rate of local recurrence. F.G.F.-2 would define a radioresistant phenotype of non at small cells bronchi carcinoma. (N.C.)

  5. DNA Hypomethylation and Histone Variant macroH2A1 Synergistically Attenuate Chemotherapy-Induced Senescence to Promote Hepatocellular Carcinoma Progression.

    Science.gov (United States)

    Borghesan, Michela; Fusilli, Caterina; Rappa, Francesca; Panebianco, Concetta; Rizzo, Giovanni; Oben, Jude A; Mazzoccoli, Gianluigi; Faulkes, Chris; Pata, Illar; Agodi, Antonella; Rezaee, Farhad; Minogue, Shane; Warren, Alessandra; Peterson, Abigail; Sedivy, John M; Douet, Julien; Buschbeck, Marcus; Cappello, Francesco; Mazza, Tommaso; Pazienza, Valerio; Vinciguerra, Manlio

    2016-02-01

    Aging is a major risk factor for progression of liver diseases to hepatocellular carcinoma (HCC). Cellular senescence contributes to age-related tissue dysfunction, but the epigenetic basis underlying drug-induced senescence remains unclear. macroH2A1, a variant of histone H2A, is a marker of senescence-associated heterochromatic foci that synergizes with DNA methylation to silence tumor-suppressor genes in human fibroblasts. In this study, we investigated the relationship between macroH2A1 splice variants, macroH2A1.1 and macroH2A1.2, and liver carcinogenesis. We found that protein levels of both macroH2A1 isoforms were increased in the livers of very elderly rodents and humans, and were robust immunohistochemical markers of human cirrhosis and HCC. In response to the chemotherapeutic and DNA-demethylating agent 5-aza-deoxycytidine (5-aza-dC), transgenic expression of macroH2A1 isoforms in HCC cell lines prevented the emergence of a senescent-like phenotype and induced synergistic global DNA hypomethylation. Conversely, macroH2A1 depletion amplified the antiproliferative effects of 5-aza-dC in HCC cells, but failed to enhance senescence. Senescence-associated secretory phenotype and whole-transcriptome analyses implicated the p38 MAPK/IL8 pathway in mediating macroH2A1-dependent escape of HCC cells from chemotherapy-induced senescence. Furthermore, chromatin immunoprecipitation sequencing revealed that this hepatic antisenescence state also required active transcription that could not be attributed to genomic occupancy of these histones. Collectively, our findings reveal a new mechanism by which drug-induced senescence is epigenetically regulated by macroH2A1 and DNA methylation and suggest macroH2A1 as a novel biomarker of hepatic senescence that could potentially predict prognosis and disease progression. PMID:26772755

  6. Inactivation of Rb in stromal fibroblasts promotes epithelial cell invasion.

    Science.gov (United States)

    Pickard, Adam; Cichon, Ann-Christin; Barry, Anna; Kieran, Declan; Patel, Daksha; Hamilton, Peter; Salto-Tellez, Manuel; James, Jacqueline; McCance, Dennis J

    2012-07-18

    Stromal-derived growth factors are required for normal epithelial growth but are also implicated in tumour progression. We have observed inactivation of the retinoblastoma protein (Rb), through phosphorylation, in cancer-associated fibroblasts in oro-pharyngeal cancer specimens. Rb is well known for its cell-autonomous effects on cancer initiation and progression; however, cell non-autonomous functions of Rb are not well described. We have identified a cell non-autonomous role of Rb, using three-dimensional cultures, where depletion of Rb in stromal fibroblasts enhances invasive potential of transformed epithelia. In part, this is mediated by upregulation of keratinocyte growth factor (KGF), which is produced by the depleted fibroblasts. KGF drives invasion of epithelial cells through induction of MMP1 expression in an AKT- and Ets2-dependent manner. Our data identify that stromal fibroblasts can alter the invasive behaviour of the epithelium, and we show that altered expression of KGF can mediate these functions. PMID:22643222

  7. Repair of DNA strand breaks in progeric fibroblasts and aging human diploid cells

    International Nuclear Information System (INIS)

    The rate of rejoining of DNA strand breaks induced by 10 krad of γ-irradiation has been studied in normal human diploid skin fibroblasts and skin fibroblasts from six patients with symptoms of progeria. Although slightly more rapid in very early passage, the repair rate in normal cells was similar throughout most of their life span in vitro. The appearance of cells with reduced repair capacity was evident as the cultures became senescent. The progeric fibroblasts varied greatly in their response to irradiation. The rate of repair was greatly reduced in two strains, whereas in two others extensive DNA degradation was consistently observed in unirradiated cells. Degradation was apparently related to the radiation received from the incorporated radiolabel. Normal repair was seen in progeric fibroblasts transformed by SV40 virus

  8. Piperlongumine Suppresses Proliferation of Human Oral Squamous Cell Carcinoma through Cell Cycle Arrest, Apoptosis and Senescence

    OpenAIRE

    San-Yuan Chen; Geng-Hung Liu; Wen-Ying Chao; Chung-Sheng Shi; Ching-Yen Lin; Yun-Ping Lim; Chieh-Hsiang Lu; Peng-Yeh Lai; Hau-Ren Chen; Ying-Ray Lee

    2016-01-01

    Oral squamous cell carcinoma (OSCC), an aggressive cancer originating in the oral cavity, is one of the leading causes of cancer deaths in males worldwide. This study investigated the antitumor activity and mechanisms of piperlongumine (PL), a natural compound isolated from Piper longum L., in human OSCC cells. The effects of PL on cell proliferation, the cell cycle, apoptosis, senescence and reactive oxygen species (ROS) levels in human OSCC cells were investigated. PL effectively inhibited ...

  9. Age, stage and senescence in plants

    OpenAIRE

    Caswell, Hal; Salguero-Gómez, Roberto

    2013-01-01

    1. Senescence (an increase in the mortality rate or force of mortality, or a decrease in fertility, with increasing age) is a widespread phenomenon. Theories about the evolution of senescence have long focused on the age trajectories of the selection gradients on mortality and fertility. In purely age-classified models, these selection gradients are non-increasing with age, implying that traits expressed early in life have a greater impact on fitness than traits expressed later in life. This ...

  10. Peach Leaf Senescence Delayed by Criconemella xenoplax

    OpenAIRE

    Nyczepir, A. P.; Wood, B. W.

    1988-01-01

    Fall annual leaf senescence of peach was delayed in the field and in microplots in the presence of Criconemella xenoplax. Soil from the rhizosphere of orchard trees with greener leaves had ca. 2.5 × more nematodes than soil around trees in a more advanced state of fall senescence. In microplots, monoclonal antibody enzyme immunoassay (EIA) of leaf cytokinins indicated that concentration of zeatin riboside-like substances and chlorophyll content were greater in leaves of trees growing in nemat...

  11. Basal Cell Carcinoma in Gorlin's Patients: a Matter of Fibroblasts-Led Protumoral Microenvironment?

    Directory of Open Access Journals (Sweden)

    Yannick Gache

    Full Text Available Basal cell carcinoma (BCC is the commonest tumor in human. About 70% sporadic BCCs bear somatic mutations in the PATCHED1 tumor suppressor gene which encodes the receptor for the Sonic Hedgehog morphogen (SHH. PATCHED1 germinal mutations are associated with the dominant Nevoid Basal Cell Carcinoma Syndrome (NBCCS, a major hallmark of which is a high susceptibility to BCCs. Although the vast majority of sporadic BCCs arises exclusively in sun exposed skin areas, 40 to 50% BCCs from NBCCS patients develop in non photo-exposed skin. Since overwhelming evidences indicate that microenvironment may both be modified by- and influence the- epithelial tumor, we hypothesized that NBCCS fibroblasts could contribute to BCCs in NBCCS patients, notably those developing in non photo-exposed skin areas. The functional impact of NBCCS fibroblasts was then assessed in organotypic skin cultures with control keratinocytes. Onset of epidermal differentiation was delayed in the presence of primary NBCCS fibroblasts. Unexpectedly, keratinocyte proliferation was severely reduced and showed high levels of nuclear P53 in both organotypic skin cultures and in fibroblast-led conditioning experiments. However, in spite of increased levels of senescence associated β-galactosidase activity in keratinocytes cultured in the presence of medium conditioned by NBCCS fibroblasts, we failed to observe activation of P16 and P21 and then of bona fide features of senescence. Constitutive extinction of P53 in WT keratinocytes resulted in an invasive phenotype in the presence of NBCCS fibroblasts. Finally, we found that expression of SHH was limited to fibroblasts but was dependent on the presence of keratinocytes. Inhibition of SHH binding resulted in improved epidermal morphogenesis. Altogether, these data suggest that the repertoire of diffusible factors (including SHH expressed by primary NBCCS fibroblasts generate a stress affecting keratinocytes behavior and epidermal homeostasis

  12. Friend or foe: emerging role of nuclear factor kappa-light-chain-enhancer of activated B cells in cell senescence

    Directory of Open Access Journals (Sweden)

    Mowla SN

    2013-09-01

    Full Text Available Sophia N Mowla,1 Neil D Perkins,2 Parmjit S Jat11Department of Neurodegenerative Disease and MRC Prion Unit, UCL Institute of Neurology, Queen Square, London, UK; 2Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UKAbstract: The nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB proteins are a family of ubiquitously expressed transcription factors that regulate the response to cellular stress. They mediate innate and adaptive immunity through the initiation of an inflammatory response to pro-inflammatory signals. The role of persistent inflammation in aiding tumor development has led to the NF-κB family of transcription factors being strongly implicated in promoting cancer. However, recent studies have now revealed that NF-κB can also function as a tumor suppressor through the induction of cellular senescence. Cellular senescence is a stable cell cycle arrest that normal cells undergo in response to a variety of intrinsic and extrinsic stimuli including: progressive telomere shortening, changes in telomeric structure, or other forms of genotoxic stress. Senescence can compromise tissue repair and regeneration, contributing to tissue and organismal aging via the accumulation of senescent cells, depletion of stem/progenitor cells and secretion of an array of inflammatory cytokines, chemokines, and matrix metalloproteinases. Senescence can also lead to the removal of potentially cancerous cells, thereby acting as a potent tumor suppressor mechanism. Herein, we review the evidence indicating a role for NF-κB in tumor suppression via cellular senescence and suggest that depending upon the subunit expressed, the biological context, and the type and intensity of the signal, NF-κB can indeed promote senescence growth arrest.Keywords: cell senescence, growth arrest, NF-κB, SASP

  13. Differential gene expression before and after ionizing radiation of subcutaneous fibroblasts identifies breast cancer patients resistant to radiation-induced fibrosis

    DEFF Research Database (Denmark)

    Alsner, Jan; Rødningen, Olaug K.; Overgaard, Jens

    2007-01-01

    BACKGROUND AND PURPOSE: Differentially gene expression between patients with either very low or very high risk of radiation-induced fibrosis (RIF) in patient-derived fibroblasts after irradiation has previously been reported. In the present study, we are investigating the robustness of radiation......-induced changes in gene expression in fibroblasts, whether differential expression is more pronounced when looking at the fold induction levels, taking into account the differences in background expression levels between patients, and whether there is a linear correlation between individual risk of RIF and......, there was no linear correlation between individual risk of RIF and differential expression of the genes investigated. Rather, differential gene expression could divide patients into two clearly separated groups, a larger, sensitive group and a smaller resistant group. CONCLUSIONS: Differential gene...

  14. Characterization and rescue of telomeric abnormalities in ICF syndrome type I fibroblasts.

    Directory of Open Access Journals (Sweden)

    Shiran eYehezkel

    2013-02-01

    Full Text Available Mutations in the human DNA methyltransferase 3B (DNMT3B gene lead to ICF (immunodeficiency, centromeric region instability, facial anomalies syndrome type I. We have previously described a telomere-related phenotype in cells from these patients, involving severe hypomethylation of subtelomeric regions, abnormally short telomeres and high levels of telomeric-repeat-containing RNA (TERRA. Here we demonstrate that ICF-patient fibroblasts carry abnormally short telomeres at a low population doubling and enter senescence prematurely. Accordingly, we attempted to rescue the senescence phenotype by ectopic expression of human telomerase, which led to elongated telomeres with hypomethylated subtelomeres. The senescence phenotype was overcome under these conditions, thus dissociating subtelomeric-DNA hypomethylation per se from the senescence phenotype. In addition, we examined whether the subtelomeric methylation could be restored by expression of a normal copy of full length DNMT3B1 in ICF fibroblasts. Ectopic expression of DNMT3B1 failed to rescue the abnormal hypomethylation at subtelomeres. However, partial rescue of subtelomeric-hypomethylation was achieved by co-expression of DNMT3B1 together with DNA methyltransferase 3-like (DNMT3L, encoding a protein that functions as a stimulator of DNMT3A and DNMT3B. DNMT3B1 and DNMT3L are predominantly expressed during early embryonic development, suggesting that de novo subtelomeric DNA methylation during crucial stages of human embryonic development may be necessary for setting and maintaining normal telomere length.

  15. Reduction of exportin 6 activity leads to actin accumulation via failure of RanGTP restoration and NTF2 sequestration in the nuclei of senescent cells

    International Nuclear Information System (INIS)

    We have previously reported that G-actin accumulation in nuclei is a universal phenomenon of cellular senescence. By employing primary culture of human diploid fibroblast (HDF) and stress-induced premature senescence (SIPS), we explored whether the failure of actin export to cytoplasm is responsible for actin accumulation in nuclei of senescent cells. Expression of exportin 6 (Exp6) and small G-protein, Ran, was significantly reduced in the replicative senescence, but not yet in SIPS, whereas nuclear import of actin by cofilin was already increased in SIPS. After treatment of young HDF cells with H2O2, rapid reduction of nuclear RanGTP was observed along with cytoplasmic increase of RanGDP. Furthermore, significantly reduced interaction of Exp6 with RanGTP was found by GST-Exp6 pull-down analysis. Failure of RanGTP restoration was accompanied with inhibition of ATP synthesis and NTF2 sequestration in the nuclei along with accordant change of senescence morphology. Indeed, knockdown of Exp6 expression significantly increased actin molecule in the nuclei of young HDF cells. Therefore, actin accumulation in nuclei of senescent cells is most likely due to the failure of RanGTP restoration with ATP deficiency and NTF2 accumulation in nuclei, which result in the decrease of actin export via Exp6 inactivation, in addition to actin import by cofilin activation.

  16. DNA-damage response network at the crossroads of cell-cycle checkpoints,cellular senescence and apoptosis

    Institute of Scientific and Technical Information of China (English)

    SCHMITT Estelle; PAQUET Claudie; BEAUCHEMIN Myriam; BERTRAND Richard

    2007-01-01

    Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation,cellular senescence and cell death.Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities.Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms.Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death.The intimate link between the cell cycle,cellular senescence,apoptosis regulation,cancer development and tumor responses to cancer treatment has become eminently apparent.Extensive research on tumor suppressor genes,oncogenes,the cell cycle and apoptosis regulatory genes has revealed how the DNA damage-sensing and -signaling pathways,referred to as the DNA-damage response network,are tied to cell proliferation,cell-cycle arrest,cellular senescence and apoptosis.DNA-damage responses are complex,involving "sensor" proteins that sense the damage,and transmit signals to "transducer" proteins,which,in turn,convey the signals to numerous "effector" proteins implicated in specific cellular pathways,including DNA repair mechanisms,cell-cycle checkpoints,cellular senescence and apoptosis.The Bcl-2 family of proteins stands among the most crucial regulators of apoptosis and performs vital functions in deciding whether a cell will live or die after cancer chemotherapy and irradiation.In addition,several studies have now revealed that members of the Bcl-2 family also interface with the cell cycle,DNA repair/recombination and cellular senescence,effects that are generally distinct from their function in apoptosis.In this review,we report progress in understanding the molecular networks that regulate cell-cycle checkpoints,cellular senescence and apoptosis after DNA damage,and discuss the influence of some Bcl-2 family members on cell-cycle checkpoint regulation.

  17. Paclitaxel targets FOXM1 to regulate KIF20A in mitotic catastrophe and breast cancer paclitaxel resistance.

    Science.gov (United States)

    Khongkow, P; Gomes, A R; Gong, C; Man, E P S; Tsang, J W-H; Zhao, F; Monteiro, L J; Coombes, R C; Medema, R H; Khoo, U S; Lam, E W-F

    2016-02-25

    FOXM1 has been implicated in taxane resistance, but the molecular mechanism involved remains elusive. In here, we show that FOXM1 depletion can sensitize breast cancer cells and mouse embryonic fibroblasts into entering paclitaxel-induced senescence, with the loss of clonogenic ability, and the induction of senescence-associated β-galactosidase activity and flat cell morphology. We also demonstrate that FOXM1 regulates the expression of the microtubulin-associated kinesin KIF20A at the transcriptional level directly through a Forkhead response element (FHRE) in its promoter. Similar to FOXM1, KIF20A expression is downregulated by paclitaxel in the sensitive MCF-7 breast cancer cells and deregulated in the paclitaxel-resistant MCF-7Tax(R) cells. KIF20A depletion also renders MCF-7 and MCF-7Tax(R) cells more sensitive to paclitaxel-induced cellular senescence. Crucially, resembling paclitaxel treatment, silencing of FOXM1 and KIF20A similarly promotes abnormal mitotic spindle morphology and chromosome alignment, which have been shown to induce mitotic catastrophe-dependent senescence. The physiological relevance of the regulation of KIF20A by FOXM1 is further highlighted by the strong and significant correlations between FOXM1 and KIF20A expression in breast cancer patient samples. Statistical analysis reveals that both FOXM1 and KIF20A protein and mRNA expression significantly associates with poor survival, consistent with a role of FOXM1 and KIF20A in paclitaxel action and resistance. Collectively, our findings suggest that paclitaxel targets the FOXM1-KIF20A axis to drive abnormal mitotic spindle formation and mitotic catastrophe and that deregulated FOXM1 and KIF20A expression may confer paclitaxel resistance. These findings provide insights into the underlying mechanisms of paclitaxel resistance and have implications for the development of predictive biomarkers and novel chemotherapeutic strategies for paclitaxel resistance. PMID:25961928

  18. Proliferation and mitogenic response to PDGF-BB of fibroblasts isolated from chronic venous leg ulcers is ulcer-age dependent

    DEFF Research Database (Denmark)

    Agren, M S; Steenfos, H H; Dabelsteen, S;

    1999-01-01

    pronounced than would have been expected based on studies on acute wounds. The objective of this study was to compare fibroblasts in culture obtained from chronic wounds (non-healing chronic venous leg ulcers), acute wounds and normal dermis regarding growth, mitogenic response to platelet-derived growth...... fibroblasts (n = 8) was significantly (p < 0.05) decreased compared with those from acute wounds (n = 10) and normal dermis (n = 5). Fibroblasts from ulcers older than 3 y grew significantly (p < 0.01) slower than those from ulcers that had been present for less than 3 y. Morphology and size of fibroblasts...... from the oldest chronic wounds deviated substantially from those of acute wounds and normal dermis, and resembled in vitro aged or senescent fibroblasts. Mitogenic response of chronic wound fibroblasts to human recombinant platelet-derived growth factor-BB was also reduced with ulcer age. No...

  19. Another Facet to the Anticancer Response to Lamellarin D: Induction of Cellular Senescence through Inhibition of Topoisomerase I and Intracellular Ros Production

    Directory of Open Access Journals (Sweden)

    Caroline Ballot

    2014-01-01

    Full Text Available Lamellarin D (LamD is a marine alkaloid with broad spectrum antitumor activities. Multiple intracellular targets of LamD, which affect cancer cell growth and induce apoptosis, have been identified. These include nuclear topoisomerase I, relevant kinases (such as cyclin-dependent kinase 2 and the mitochondrial electron transport chain. While we have previously demonstrated that LamD at micromolar range deploys strong cytotoxicity by inducing mitochondrial apoptosis, mechanisms of its cytostatic effect have not yet been characterized. Here, we demonstrated that induction of cellular senescence (depicted by cell cycle arrest in G2 associated with β-galactosidase activity is a common response to subtoxic concentrations of LamD. Cellular senescence is observed in a large panel of cancer cells following in vitro or in vivo exposure to LamD. The onset of cellular senescence is dependent on the presence of intact topoisomerase I since topoisomerase I-mutated cells are resistant to senescence induced by LamD. LamD-induced senescence occurs without important loss of telomere integrity. Instead, incubation with LamD results in the production of intracellular reactive oxygen species (ROS, which are critical for senescence as demonstrated by the inhibitory effect of antioxidants. In addition, cancer cells lacking mitochondrial DNA also exhibit cellular senescence upon LamD exposure indicating that LamD can trigger senescence, unlike apoptosis, in the absence of functional mitochondria. Overall, our results identify senescence-associated growth arrest as a powerful effect of LamD and add compelling evidence for the pharmacological interest of lamellarins as potential anticancer agents.

  20. Human umbilical cord Wharton's jelly mesenchymal stem cells do not transform to tumor-associated fibroblasts in the presence of breast and ovarian cancer cells unlike bone marrow mesenchymal stem cells.

    Science.gov (United States)

    Subramanian, Arjunan; Shu-Uin, Gan; Kae-Siang, Ngo; Gauthaman, Kalamegam; Biswas, Arijit; Choolani, Mahesh; Bongso, Ariff; Chui-Yee, Fong

    2012-06-01

    Human bone marrow mesenchymal stem cells (hBMMSCs) were shown to transform into tumor-associated fibroblasts (TAFs) when in the vicinity of breast cancer tumors and played an important role in tumor enhancement and metastasis. In early human development MSCs migrating from the yolk sac and aorta-gonad-mesonephros (AGM) via the umbilical cord to the placenta and back to the fetal bone marrow were shown to get trapped in the gelatinous Wharton's jelly of the umbilical cord. The common origin of the Wharton's jelly MSCs and the finally homed hBMMSCs prompted us to evaluate whether hWJSCs are also involved in TAF transformation. hWJSCs and hBMMSCs were grown in the presence of breast and ovarian cancer cell conditioned medium (MDA-TCM, TOV-TCM) for 30 days. No changes were observed in the hWJSCs but the hBMMSCs transformed from short to thin long fibroblasts, their proliferation rates increased and CD marker expression decreased. The transformed hBMMSCs showed positive staining for the tumor-associated markers FSP, VEGF, EGF, and Tn-C. Real-time PCR and multiplex luminex bead analysis showed upregulation of TAF-related genes (FSP, FAP, Tn-C, Tsp-1, EGF, bFGF, IL-6, α-SMA, VEGF, and TGF-β) for hBMMSCs with low expression for hWJSCs. The luciferase assay showed that hWJSCs previously exposed to MDA-TCM or TOV-TCM had no stimulatory growth effect on luciferase-tagged MDA or TOV cells unlike hBMMSCs. The results confirmed that hWJSCs do not transform to the TAF phenotype and may therefore not be associated with enhanced growth of solid tumors making them a safe MSC for cell based therapies. PMID:22234854

  1. A Micro-RNA Connection in BRafV600E-Mediated Premature Senescence of Human Melanocytes

    Directory of Open Access Journals (Sweden)

    Gang Ren

    2012-01-01

    Full Text Available Recent high-throughput-sequencing of the cancer genome has identified oncogenic mutations in BRaf genetic locus as one of the critical events in melanomagenesis. In normal cells, the activity of BRaf is tightly regulated. Gain-of-function mutations like those identified in melanoma frequently lead to enhanced cell-survival and unrestrained growth. The activating mutation of BRaf will also induce the cells to senesce. However, the mechanism by which the oncogenic BRaf induces the senescent barrier remains poorly defined. microRNAs have regulatory functions toward the expression of genes that are important in carcinogenesis. Here we show that expression of several microRNAs is altered when the oncogenic version of BRaf is introduced in cultured primary melanocytes and these cells undergo premature cellular senescence. These include eight microRNAs whose expression rates are significantly stimulated and three that are repressed. While most of the induced microRNAs have documented negative effects on cell cycle progression, one of the repressed microRNAs has proven oncogenic functions. Ectopic expression of some of these induced microRNAs increased the expression of senescence markers and induced growth arrest and senescence in primary melanocytes. Taken together, our results suggest that the change in microRNA expression rates may play a vital role in senescence induced by the oncogenic BRaf.

  2. Acute dyskerin depletion triggers cellular senescence and renders osteosarcoma cells resistant to genotoxic stress-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ping; Mobasher, Maral E.; Alawi, Faizan, E-mail: falawi@upenn.edu

    2014-04-18

    Highlights: • Dyskerin depletion triggers cellular senescence in U2OS osteosarcoma cells. • Dyskerin-depleted cells are resistant to apoptosis induced by genotoxic stress. • Chromatin relaxation sensitizes dyskerin-depleted cells to apoptosis. - Abstract: Dyskerin is a conserved, nucleolar RNA-binding protein implicated in an increasing array of fundamental cellular processes. Germline mutation in the dyskerin gene (DKC1) is the cause of X-linked dyskeratosis congenita (DC). Conversely, wild-type dyskerin is overexpressed in sporadic cancers, and high-levels may be associated with poor prognosis. It was previously reported that acute loss of dyskerin function via siRNA-mediated depletion slowed the proliferation of transformed cell lines. However, the mechanisms remained unclear. Using human U2OS osteosarcoma cells, we show that siRNA-mediated dyskerin depletion induced cellular senescence as evidenced by proliferative arrest, senescence-associated heterochromatinization and a senescence-associated molecular profile. Senescence can render cells resistant to apoptosis. Conversely, chromatin relaxation can reverse the repressive effects of senescence-associated heterochromatinization on apoptosis. To this end, genotoxic stress-induced apoptosis was suppressed in dyskerin-depleted cells. In contrast, agents that induce chromatin relaxation, including histone deacetylase inhibitors and the DNA intercalator chloroquine, sensitized dyskerin-depleted cells to apoptosis. Dyskerin is a core component of the telomerase complex and plays an important role in telomere homeostasis. Defective telomere maintenance resulting in premature senescence is thought to primarily underlie the pathogenesis of X-linked DC. Since U2OS cells are telomerase-negative, this leads us to conclude that loss of dyskerin function can also induce cellular senescence via mechanisms independent of telomere shortening.

  3. Senescence-accelerated mouse (SAM): a novel murine model of senescence.

    Science.gov (United States)

    Takeda, T; Hosokawa, M; Higuchi, K

    1997-01-01

    The Senescence-Accelerated Mouse (SAM) has been under development by our research team at Kyoto University since 1970 through the selective inbreeding of the AKR/J strain of mice donated by the Jackson Laboratory in 1968, based on a graded score for senescence, life span, and pathologic phenotype. At present, there are 12 lines of SAM: nine senescence-prone inbred strains (SAMP) including SAMP1, SAMP2, SAMP3, SAMP6, SAMP7, SAMP8, SAMP9, SAMP10, and SAMP11; and three senescence-resistant inbred strains (SAMR) including SAMR1, SAMR4, and SAMR5. Data from survival curves, Gompertzian function, and grading score of senescence, together with growth patterns of body weight of these SAMP and SAMR, revealed that the characteristic feature of aging common to all SAMP mice is "accelerated senescence;" early onset and irreversible advance of senescence manifested by several signs and gross lesions such as the loss of normal behavior, various skin lesions, increased lordokyphosis, etc., after a period of normal development. In the course of SAM development, it became evident that SAMP strains manifest various pathologic phenotypes that are characteristic enough to differentiate the SAM strains. The genetic background and significance of SAM development are discussed. PMID:9088907

  4. Senescence rates in patients with end-stage renal disease

    DEFF Research Database (Denmark)

    Koopman, J J E; Rozing, M P; Kramer, Ada;

    2011-01-01

    function of the Gompertz equation as a superior descriptor of senescence rate. Here, we tested both measures of the rate of senescence in a population of patients with end-stage renal disease. It is clinical dogma that patients on dialysis experience accelerated senescence, whereas those with a functional...

  5. HDACs and the senescent phenotype of WI-38 cells

    Directory of Open Access Journals (Sweden)

    Noonan Emily J

    2005-10-01

    Full Text Available Abstract Background Normal cells possess a limited proliferative life span after which they enter a state of irreversible growth arrest. This process, known as replicative senescence, is accompanied by changes in gene expression that give rise to a variety of senescence-associated phenotypes. It has been suggested that these gene expression changes result in part from alterations in the histone acetylation machinery. Here we examine the influence of HDAC inhibitors on the expression of senescent markers in pre- and post-senescent WI-38 cells. Results Pre- and post-senescent WI-38 cells were treated with the HDAC inhibitors butyrate or trichostatin A (TSA. Following HDAC inhibitor treatment, pre-senescent cells increased p21WAF1 and β-galactosidase expression, assumed a flattened senescence-associated morphology, and maintained a lower level of proteasome activity. These alterations also occurred during normal replicative senescence of WI-38 cells, but were not accentuated further by HDAC inhibitors. We also found that HDAC1 levels decline during normal replicative senescence. Conclusion Our findings indicate that HDACs impact numerous phenotypic changes associated with cellular senescence. Reduced HDAC1 expression levels in senescent cells may be an important event in mediating the transition to a senescent phenotype.

  6. The thyroid hormone receptor β induces DNA damage and premature senescence

    OpenAIRE

    Zambrano, Alberto; García-Carpizo, Verónica; Gallardo, M. Esther; Villamuera, Raquel; Gómez-Ferrería, María Ana; Pascual, Ángel; Buisine, Nicolas; Sachs, Laurent M.; Garesse, Rafael; Aranda, Ana

    2014-01-01

    There is increasing evidence that the thyroid hormone (TH) receptors (THRs) can play a role in aging, cancer and degenerative diseases. In this paper, we demonstrate that binding of TH T3 (triiodothyronine) to THRB induces senescence and deoxyribonucleic acid (DNA) damage in cultured cells and in tissues of young hyperthyroid mice. T3 induces a rapid activation of ATM (ataxia telangiectasia mutated)/PRKAA (adenosine monophosphate- activated protein kinase) signal transduction and recruitment ...

  7. Senescence in fungi: the view from Neurospora.

    Science.gov (United States)

    Maheshwari, Ramesh; Navaraj, Arunasalam

    2008-03-01

    Some naturally occurring strains of fungi cease growing through successive subculturing, i.e., they senesce. In Neurospora, senescing strains usually contain intramitochondrial linear or circular plasmids. An entire plasmid or its part(s) integrates into the mtDNA, causing insertional mutagenesis. The functionally defective mitochondria replicate faster than the wild-type mitochondria and spread through interconnected hyphal cells. Senescence could also be due to spontaneous lethal nuclear gene mutations arising in the multinucleated mycelium. However, their phenotypic effects remain masked until the nuclei segregate into a homokaryotic spore, and the spore germinates to form a mycelium that is incapable of extended culturing. Ultimately the growth of a fungal colony ceases due to dysfunctional oxidative phosphorylation. Results with senescing nuclear mutants or growth-impaired cytoplasmic mutants suggest that mtDNA is inherently unstable, requiring protection by as yet unidentified nuclear-gene-encoded factors for normal functioning. Interestingly, these results are in accord with the endosymbiotic theory of origin of eukaryotic cells. PMID:18093134

  8. T cell senescence and cardiovascular diseases.

    Science.gov (United States)

    Yu, Hee Tae; Park, Sungha; Shin, Eui-Cheol; Lee, Won-Woo

    2016-08-01

    Age-related changes in the immune system, commonly termed "immunosenescence," contribute to deterioration of the immune response and fundamentally impact the health and survival of elderly individuals. Immunosenescence affects both the innate and adaptive immune systems; however, the most notable changes are in T cell immunity and include thymic involution, the collapse of T cell receptor (TCR) diversity, an imbalance in T cell populations, and the clonal expansion of senescent T cells. Senescent T cells have the ability to produce large quantities of proinflammatory cytokines and cytotoxic mediators; thus, they have been implicated in the pathogenesis of many chronic inflammatory diseases. Recently, an increasing body of evidence has suggested that senescent T cells also have pathogenic potential in cardiovascular diseases, such as hypertension, atherosclerosis, and myocardial infarction, underscoring the detrimental roles of these cells in various chronic inflammatory responses. Given that cardiovascular disease is the number one cause of death worldwide, there is great interest in understanding the contribution of age-related immunological changes to its pathogenesis. In this review, we discuss general features of age-related alterations in T cell immunity and the possible roles of senescent T cells in the pathogenesis of cardiovascular disease. PMID:26188489

  9. Telomerase Therapy to Reverse Cardiovascular Senescence

    OpenAIRE

    Nazari-Shafti, Timo Z.; Cooke, John P

    2015-01-01

    Cellular senescence of endothelial cells plays an important role in the development of vascular lesions that ultimately lead to an atherosclerotic plaque. This review focuses on the age-related changes of endothelial and vascular smooth muscle cells that contribute to vascular disease and discusses potential new targets that could rejuvenate the vascular system and thereby prevent or delay atherosclerosis.

  10. Change and aging senescence as an adaptation.

    Directory of Open Access Journals (Sweden)

    André C R Martins

    Full Text Available Understanding why we age is a long-lived open problem in evolutionary biology. Aging is prejudicial to the individual, and evolutionary forces should prevent it, but many species show signs of senescence as individuals age. Here, I will propose a model for aging based on assumptions that are compatible with evolutionary theory: i competition is between individuals; ii there is some degree of locality, so quite often competition will be between parents and their progeny; iii optimal conditions are not stationary, and mutation helps each species to keep competitive. When conditions change, a senescent species can drive immortal competitors to extinction. This counter-intuitive result arises from the pruning caused by the death of elder individuals. When there is change and mutation, each generation is slightly better adapted to the new conditions, but some older individuals survive by chance. Senescence can eliminate those from the genetic pool. Even though individual selection forces can sometimes win over group selection ones, it is not exactly the individual that is selected but its lineage. While senescence damages the individuals and has an evolutionary cost, it has a benefit of its own. It allows each lineage to adapt faster to changing conditions. We age because the world changes.

  11. Mitochondria change dynamics and morphology during grapevine leaf senescence.

    Directory of Open Access Journals (Sweden)

    Cristina Ruberti

    Full Text Available Leaf senescence is the last stage of development of an organ and is aimed to its ordered disassembly and nutrient reallocation. Whereas chlorophyll gradually degrades during senescence in leaves, mitochondria need to maintain active to sustain the energy demands of senescing cells. Here we analysed the motility and morphology of mitochondria in different stages of senescence in leaves of grapevine (Vitis vinifera, by stably expressing a GFP (green fluorescent protein reporter targeted to these organelles. Results show that mitochondria were less dynamic and markedly changed morphology during senescence, passing from the elongated, branched structures found in mature leaves to enlarged and sparse organelles in senescent leaves. Progression of senescence in leaves was not synchronous, since changes in mitochondria from stomata were delayed. Mitochondrial morphology was also analysed in grapevine cell cultures. Mitochondria from cells at the end of their growth curve resembled those from senescing leaves, suggesting that cell cultures might represent a useful model system for senescence. Additionally, senescence-associated mitochondrial changes were observed in plants treated with high concentrations of cytokinins. Overall, morphology and dynamics of mitochondria might represent a reliable senescence marker for plant cells.

  12. New concept: cellular senescence in pathophysiology of cholangiocarcinoma.

    Science.gov (United States)

    Sasaki, Motoko; Nakanuma, Yasuni

    2016-05-01

    Cholangiocarcinoma, a malignant tumor arising in the hepatobiliary system, presents with poor prognosis because of difficulty in its early detection/diagnosis. Recent progress revealed that cellular senescence may be involved in the pathophysiology of cholangiocarcinoma. Cellular senescence is defined as permanent growth arrest caused by several cellular injuries, such as oncogenic mutations and oxidative stress. "Oncogene-induced" and/or stress-induced senescence may occur in the process of multi-step cholangiocarcinogenesis, and overexpression of a polycomb group protein EZH2 may play a role in the escape from, and/or bypassing of, senescence. Furthermore, senescent cells may play important roles in tumor development and progression via the production of senescence-associated secretory phenotypes. Cellular senescence may be a new target for the prevention, early diagnosis, and therapy of cholangiocarcinoma in the near future. PMID:26680649

  13. Use of NAP gene to manipulate leaf senescence in plants

    Science.gov (United States)

    Gan, Susheng; Guo, Yongfeng

    2013-04-16

    The present invention discloses transgenic plants having an altered level of NAP protein compared to that of a non-transgenic plant, where the transgenic plants display an altered leaf senescence phenotype relative to a non-transgenic plant, as well as mutant plants comprising an inactivated NAP gene, where mutant plants display a delayed leaf senescence phenotype compared to that of a non-mutant plant. The present invention also discloses methods for delaying leaf senescence in a plant, as well as methods of making a mutant plant having a decreased level of NAP protein compared to that of a non-mutant plant, where the mutant plant displays a delayed leaf senescence phenotype relative to a non-mutant plant. Methods for causing precocious leaf senescence or promoting leaf senescence in a plant are also disclosed. Also disclosed are methods of identifying a candidate plant suitable for breeding that displays a delayed leaf senescence and/or enhanced yield phenotype.

  14. Fibroblast differentiation in subcutaneous fibrosis after postmastectomy radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Herskind, C.; Johansen, J.; Bentzen, S.M.; Overgaard, M.; Overgaard, J.; Bamberg, M.; Rodemann, H.P. [Univ. of Tuebingen (Germany). Section of Radiobiology and Molecular Environmental Research

    2000-07-01

    In order to acquire a better understanding of the mechanism of radiation-induced fibrosis, we studied the differentiation of normal skin fibroblasts cultured from breast cancer radiotherapy patients with different risk of fibrosis. The differentiation state of fibroblasts was characterized in clonal cultures using established cytomorphological criteria. Collagen synthesis was determined by 3H-proline incorporation into pepsin-resistant protein. Radiation-induced inactivation of fibroblasts was paralleled by an increase in terminally differentiated fibrocytes, demonstrating that premature terminal differentiation is an important response to irradiation of fibroblasts from radiotherapy patients. Surviving colony-forming fibroblasts showed a change in differentiation with an increase in the ratio L:E of progenitor fibroblasts in late (L) compared to early (E) differentiation states. Furthermore, increased collagen production was observed after irradiation. The results provide evidence supporting a role of terminal fibroblast differentiation in radiation-induced fibrosis and imply that the progenitor population surviving radiotherapy might be more prone to terminal differentiation than before radiotherapy.

  15. Tinospora cordifolia Induces Differentiation and Senescence Pathways in Neuroblastoma Cells.

    Science.gov (United States)

    Mishra, Rachana; Kaur, Gurcharan

    2015-08-01

    Children diagnosed with neuroblastomas often suffer from severe side as well as late effects of conventional treatments like chemotherapy and radiotherapy. Recent advances in understanding of molecular pathways involved in cellular differentiation and apoptosis have helped in the development of new therapeutic approach based on differentiation-based therapy of malignant tumours. Natural medicines with their holistic therapeutic approach are known to selectively eliminate cancer cells thus provide a better substitute for the conventional treatment modes. The current study was aimed to investigate the anti-cancer potential of aqueous ethanolic extract of Tinospora cordifolia (TCE) using IMR-32 human neuroblastoma cell line as a model system. TCE is highly recommended in Ayurveda for its general body and metal health-promoting properties. TCE treatment was seen to arrest the majority of cells in G0/G1 phase and modulated the expression of DNA clamp sliding protein (PCNA) and cyclin D1. Further, TCE-treated cells showed differentiation as revealed by their morphology and the expression of neuronal cell specific differentiation markers NF200, MAP-2 and NeuN in neuroblastoma cells. The differentiated phenotype was associated with induction of senescence and pro-apoptosis pathways by enhancing expression of senescence marker mortalin and Rel A subunit of nuclear factor kappa beta (NFkB) along with decreased expression of anti-apoptotic marker, Bcl-xl. TCE exhibited anti-metastatic activity and significantly reduced cell migration in the scratched area along with downregulation of neural cell adhesion molecule (NCAM) polysialylation and secretion of matrix metalloproteinases (MMPs). Our data suggest that crude extract or active phytochemicals from this plant may be a potential candidate for differentiation-based therapy of malignant neuroblastoma cells. PMID:25280667

  16. MicroRNA-34a induces a senescence-like change via the down-regulation of SIRT1 and up-regulation of p53 protein in human esophageal squamous cancer cells with a wild-type p53 gene background.

    Science.gov (United States)

    Ye, Zhimin; Fang, Jun; Dai, Shujun; Wang, Yuezhen; Fu, Zhenfu; Feng, Wei; Wei, Qichun; Huang, Pintong

    2016-01-28

    MiR-34a has been reported as a non-coding RNA universally expressed in normal old cells and a probable suppressor of diverse cancer cells; however, this miRNA's expression and anti-tumor mechanism in esophageal squamous cancer cells (ESCC) remains unclear. We explored these questions in three human ESCC lines, KYSE-450, KYSE-410, and ECa-109, with wild-type p53 and mutant p53 backgrounds. Through a specific stem-loop RT primer for miR-34a, we examined the relevant expression level of miR-34a in these three cell lines using real-time reverse transcription PCR (qRT-PCR). We found that the expression level of miR-34a induced by the DNA damage agent adrmycin (ADR) was both p53- and time-dependent. Following incubation with miR-34a, cellular growth inhibition was exhibited differently in the three cell lines harbored with different p53 backgrounds. Furthermore, the MTT assay demonstrated an miR-34a-related cytotoxic effect in cell growth. Senescence-associated β-galactosidase (SA-β-Gal) staining was used to examine senescence-like phenotypes induced by miR-34a. Mechanistic investigation suggested that the down-regulation of Sirtuin1 (SIRT1) and up-regulation of p53/p21 contributed to the anti-tumor mechanism of miR-34a in wild-type p53 ECa-109 cells, while neither of the apoptosis-related proteins PARP and caspase-3 caused significant changes. In summary, our findings indicated that the intrinsic expression of miR-34a was relatively low and was expressed differently among different p53 backgrounds and ADR treatment times. The anti-tumor effect of miR-34a was primarily dependent on the regulation of SIRT1 and p53/p21 protein, not apoptosis-associated proteins. PMID:26523671

  17. Nanog induces suppression of senescence through downregulation of p27KIP1 expression

    Science.gov (United States)

    Münst, Bernhard; Thier, Marc Christian; Winnemöller, Dirk; Helfen, Martina; Thummer, Rajkumar P.; Edenhofer, Frank

    2016-01-01

    ABSTRACT A comprehensive analysis of the molecular network of cellular factors establishing and maintaining pluripotency as well as self renewal of pluripotent stem cells is key for further progress in understanding basic stem cell biology. Nanog is necessary for the natural induction of pluripotency in early mammalian development but dispensable for both its maintenance and its artificial induction. To gain further insight into the molecular activity of Nanog, we analyzed the outcomes of Nanog gain-of-function in various cell models employing a recently developed biologically active recombinant cell-permeant protein, Nanog-TAT. We found that Nanog enhances the proliferation of both NIH 3T3 and primary fibroblast cells. Nanog transduction into primary fibroblasts results in suppression of senescence-associated β-galactosidase activity. Investigation of cell cycle factors revealed that transient activation of Nanog correlates with consistent downregulation of the cell cycle inhibitor p27KIP1 (also known as CDKN1B). By performing chromatin immunoprecipitation analysis, we confirmed bona fide Nanog-binding sites upstream of the p27KIP1 gene, establishing a direct link between physical occupancy and functional regulation. Our data demonstrates that Nanog enhances proliferation of fibroblasts through transcriptional regulation of cell cycle inhibitor p27 gene. PMID:26795560

  18. High EMT Signature Score of Invasive Non-Small Cell Lung Cancer (NSCLC Cells Correlates with NFκB Driven Colony-Stimulating Factor 2 (CSF2/GM-CSF Secretion by Neighboring Stromal Fibroblasts.

    Directory of Open Access Journals (Sweden)

    Albin Rudisch

    Full Text Available We established co-cultures of invasive or non-invasive NSCLC cell lines and various types of fibroblasts (FBs to more precisely characterize the molecular mechanism of tumor-stroma crosstalk in lung cancer. The HGF-MET-ERK1/2-CREB-axis was shown to contribute to the onset of the invasive phenotype of Calu-1 with HGF being secreted by FBs. Differential expression analysis of the respective mono- and co-cultures revealed an upregulation of NFκB-related genes exclusively in co-cultures with Calu-1. Cytokine Array- and ELISA-based characterization of the "cytokine fingerprints" identified CSF2 (GM-CSF, CXCL1, CXCL6, VEGF, IL6, RANTES and IL8 as being specifically upregulated in various co-cultures. Whilst CXCL6 exhibited a strictly FB-type-specific induction profile regardless of the invasiveness of the tumor cell line, CSF2 was only induced in co-cultures of invasive cell lines regardless of the partnered FB type. These cultures revealed a clear link between the induction of CSF2 and the EMT signature of the cancer cell line. The canonical NFκB signaling in FBs, but not in tumor cells, was shown to be responsible for the induced and constitutive CSF2 expression. In addition to CSF2, cytokine IL6, IL8 and IL1B, and chemokine CXCL1 and CXCL6 transcripts were also shown to be increased in co-cultured FBs. In contrast, their induction was not strictly dependent on the invasiveness of the co-cultured tumor cell. In a multi-reporter assay, additional signaling pathways (AP-1, HIF1-α, KLF4, SP-1 and ELK-1 were found to be induced in FBs co-cultured with Calu-1. Most importantly, no difference was observed in the level of inducibility of these six signaling pathways with regard to the type of FBs used. Finally, upon tumor fibroblast interaction the massive induction of chemokines such as CXCL1 and CXCL6 in FBs might be responsible for increased recruitment of a monocytic cell line (THP-1 in a transwell assay.

  19. Protein Kinase CK2 Regulates Cytoskeletal Reorganization during Ionizing Radiation-Induced Senescence of Human Mesenchymal Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Daojing; Jang, Deok-Jin

    2009-08-21

    Human mesenchymal stem cells (hMSC) are critical for tissue regeneration. How hMSC respond to genotoxic stresses and potentially contribute to aging and cancer remain underexplored. We demonstrated that ionizing radiation induced cellular senescence of hMSC over a period of 10 days, showing a critical transition between day 3 and day 6. This was confirmed by senescence-associated beta-galactosidase (SA-{beta}-gal) staining, protein expression profiles of key cell cycle regulators (retinoblastoma (Rb) protein, p53, p21{sup waf1/Cip1}, and p16{sup INK4A}), and senescence-associated secretory phenotypes (SASPs) (IL-8, IL-12, GRO, and MDC). We observed dramatic cytoskeletal reorganization of hMSC through reduction of myosin-10, redistribution of myosin-9, and secretion of profilin-1. Using a SILAC-based phosphoproteomics method, we detected significant reduction of myosin-9 phosphorylation at Ser1943, coinciding with its redistribution. Importantly, through treatment with cell permeable inhibitors (4,5,6,7-tetrabromo-1H-benzotriazole (TBB) and 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole (DMAT)), and gene knockdown using RNA interference, we identified CK2, a kinase responsible for myosin-9 phosphorylation at Ser1943, as a key factor contributing to the radiation-induced senescence of hMSC. We showed that individual knockdown of CK2 catalytic subunits CK2{alpha} and CK2{alpha}{prime} induced hMSC senescence. However, only knockdown of CK2{alpha} resulted in morphological phenotypes resembling those of radiation-induced senescence. These results suggest that CK2{alpha} and CK2{alpha}{prime} play differential roles in hMSC senescence progression, and their relative expression might represent a novel regulatory mechanism for CK2 activity.

  20. Resveratrol induces cellular senescence with attenuated mono-ubiquitination of histone H2B in glioma cells

    International Nuclear Information System (INIS)

    Research highlights: → Resveratrol induces cellular senescence in glioma cell. → Resveratrol inhibits mono-ubiquitination of histone H2B at K120. → Depletion of RNF20, phenocopies the inhibitory effects of resveratrol. → Mono-ubiquitination of histone H2B at K120 is a novel target of resveratrol. → RNF20 inhibits cellular senescence in proliferating glioma cells. -- Abstract: Resveratrol (3,4',5-trihydroxy-trans-stilbene), a polyphenol naturally occurring in grapes and other plants, has cancer chemo-preventive effects and therapeutic potential. Although resveratrol modulates multiple pathways in tumor cells, how resveratrol or its affected pathways converge on chromatin to mediate its effects is not known. Using glioma cells as a model, we showed here that resveratrol inhibited cell proliferation and induced cellular hypertrophy by transforming spindle-shaped cells to enlarged, irregular and flatten-shaped ones. We further showed that resveratrol-induced hypertrophic cells expressed senescence-associated-β-galactosidase, suggesting that resveratrol-induced cellular senescence in glioma cells. Consistent with these observations, we demonstrated that resveratrol inhibited clonogenic efficiencies in vitro and tumor growth in a xenograft model. Furthermore, we found that acute treatment of resveratrol inhibited mono-ubiquitination of histone H2B at K120 (uH2B) in breast, prostate, pancreatic, lung, brain tumor cells as well as primary human cells. Chronic treatment with low doses of resveratrol also inhibited uH2B in the resveratrol-induced senescent glioma cells. Moreover, we showed that depletion of RNF20, a ubiquitin ligase of histone H2B, inhibited uH2B and induced cellular senescence in glioma cells in vitro, thereby recapitulated the effects of resveratrol. Taken together, our results suggest that uH2B is a novel direct or indirect chromatin target of resveratrol and RNF20 plays an important role in inhibiting cellular senescence programs that are

  1. Bioactive Constituents of Zanthoxylum rhetsa Bark and Its Cytotoxic Potential against B16-F10 Melanoma Cancer and Normal Human Dermal Fibroblast (HDF) Cell Lines.

    Science.gov (United States)

    Santhanam, Ramesh Kumar; Ahmad, Syahida; Abas, Faridah; Safinar Ismail, Intan; Rukayadi, Yaya; Tayyab Akhtar, Muhammad; Shaari, Khozirah

    2016-01-01

    Zanthoxylum rhetsa is an aromatic tree, known vernacularly as "Indian Prickly Ash". It has been predominantly used by Indian tribes for the treatment of many infirmities like diabetes, inflammation, rheumatism, toothache and diarrhea. In this study, we identified major volatile constituents present in different solvent fractions of Z. rhetsa bark using GC-MS analysis and isolated two tetrahydrofuran lignans (yangambin and kobusin), a berberine alkaloid (columbamine) and a triterpenoid (lupeol) from the bioactive chloroform fraction. The solvent fractions and purified compounds were tested for their cytotoxic potential against human dermal fibroblasts (HDF) and mouse melanoma (B16-F10) cells, using the MTT assay. All the solvent fractions and purified compounds were found to be non-cytotoxic to HDF cells. However, the chloroform fraction and kobusin exhibited cytotoxic effect against B16-F10 melanoma cells. The presence of bioactive lignans and alkaloids were suggested to be responsible for the cytotoxic property of Z. rhetsa bark against B16-F10 cells. PMID:27231889

  2. Bioactive Constituents of Zanthoxylum rhetsa Bark and Its Cytotoxic Potential against B16-F10 Melanoma Cancer and Normal Human Dermal Fibroblast (HDF Cell Lines

    Directory of Open Access Journals (Sweden)

    Ramesh Kumar Santhanam

    2016-05-01

    Full Text Available Zanthoxylum rhetsa is an aromatic tree, known vernacularly as “Indian Prickly Ash”. It has been predominantly used by Indian tribes for the treatment of many infirmities like diabetes, inflammation, rheumatism, toothache and diarrhea. In this study, we identified major volatile constituents present in different solvent fractions of Z. rhetsa bark using GC-MS analysis and isolated two tetrahydrofuran lignans (yangambin and kobusin, a berberine alkaloid (columbamine and a triterpenoid (lupeol from the bioactive chloroform fraction. The solvent fractions and purified compounds were tested for their cytotoxic potential against human dermal fibroblasts (HDF and mouse melanoma (B16-F10 cells, using the MTT assay. All the solvent fractions and purified compounds were found to be non-cytotoxic to HDF cells. However, the chloroform fraction and kobusin exhibited cytotoxic effect against B16-F10 melanoma cells. The presence of bioactive lignans and alkaloids were suggested to be responsible for the cytotoxic property of Z. rhetsa bark against B16-F10 cells.

  3. A gain-of-function senescence bypass screen identifies the homeobox transcription factor DLX2 as a regulator of ATM-p53 signaling.

    Science.gov (United States)

    Wang, Yifan; Xu, Qikai; Sack, Laura; Kang, Chanhee; Elledge, Stephen J

    2016-02-01

    Senescence stimuli activate multiple tumor suppressor pathways to initiate cycle arrest and a differentiation program characteristic of senescent cells. We performed a two-stage, gain-of-function screen to select for the genes whose enhanced expression can bypass replicative senescence. We uncovered multiple genes known to be involved in p53 and Rb regulation and ATM regulation, two components of the CST (CTC1-STN1-TEN1) complex involved in preventing telomere erosion, and genes such as REST and FOXO4 that have been implicated in aging. Among the new genes now implicated in senescence, we identified DLX2, a homeobox transcription factor that has been shown to be required for tumor growth and metastasis and is associated with poor cancer prognosis. Growth analysis showed that DLX2 expression led to increased cellular replicative life span. Our data suggest that DLX2 expression reduces the protein components of the TTI1/TTI2/TEL2 complex, a key complex required for the proper folding and stabilization of ATM and other members of the PIKK (phosphatidylinositol 3-kinase-related kinase) family kinase, leading to reduced ATM-p53 signaling and senescence bypass. We also found that the overexpression of DLX2 exhibited a mutually exclusive relationship with p53 alterations in cancer patients. Our functional screen identified novel players that may promote tumorigenesis by regulating the ATM-p53 pathway and senescence. PMID:26833729

  4. Exercise Prevents Diet-Induced Cellular Senescence in Adipose Tissue.

    Science.gov (United States)

    Schafer, Marissa J; White, Thomas A; Evans, Glenda; Tonne, Jason M; Verzosa, Grace C; Stout, Michael B; Mazula, Daniel L; Palmer, Allyson K; Baker, Darren J; Jensen, Michael D; Torbenson, Michael S; Miller, Jordan D; Ikeda, Yasuhiro; Tchkonia, Tamara; van Deursen, Jan M; Kirkland, James L; LeBrasseur, Nathan K

    2016-06-01

    Considerable evidence implicates cellular senescence in the biology of aging and chronic disease. Diet and exercise are determinants of healthy aging; however, the extent to which they affect the behavior and accretion of senescent cells within distinct tissues is not clear. Here we tested the hypothesis that exercise prevents premature senescent cell accumulation and systemic metabolic dysfunction induced by a fast-food diet (FFD). Using transgenic mice that express EGFP in response to activation of the senescence-associated p16(INK4a) promoter, we demonstrate that FFD consumption causes deleterious changes in body weight and composition as well as in measures of physical, cardiac, and metabolic health. The harmful effects of the FFD were associated with dramatic increases in several markers of senescence, including p16, EGFP, senescence-associated β-galactosidase, and the senescence-associated secretory phenotype (SASP) specifically in visceral adipose tissue. We show that exercise prevents the accumulation of senescent cells and the expression of the SASP while nullifying the damaging effects of the FFD on parameters of health. We also demonstrate that exercise initiated after long-term FFD feeding reduces senescent phenotype markers in visceral adipose tissue while attenuating physical impairments, suggesting that exercise may provide restorative benefit by mitigating accrued senescent burden. These findings highlight a novel mechanism by which exercise mediates its beneficial effects and reinforces the effect of modifiable lifestyle choices on health span. PMID:26983960

  5. Cristacarpin promotes ER stress-mediated ROS generation leading to premature senescence by activation of p21(waf-1).

    Science.gov (United States)

    Chakraborty, Souneek; Rasool, Reyaz Ur; Kumar, Sunil; Nayak, Debasis; Rah, Bilal; Katoch, Archana; Amin, Hina; Ali, Asif; Goswami, Anindya

    2016-06-01

    Stress-induced premature senescence (SIPS) is quite similar to replicative senescence that is committed by cells exposed to various stress conditions viz. ultraviolet radiation (DNA damage), hydrogen peroxide (oxidative stress), chemotherapeutic agents (cytotoxic threat), etc. Here, we report that cristacarpin, a natural product obtained from the stem bark of Erythrina suberosa, promotes endoplasmic reticulum (ER) stress, leading to sub-lethal reactive oxygen species (ROS) generation and which eventually terminates by triggering senescence in pancreatic and breast cancer cells through blocking the cell cycle in the G1 phase. The majority of cristacarpin-treated cells responded to conventional SA-β-gal stains; showed characteristic p21(waf1) upregulation along with enlarged and flattened morphology; and increased volume, granularity, and formation of heterochromatin foci-all of these features are the hallmarks of senescence. Inhibition of ROS generation by N-acetyl-L-cysteine (NAC) significantly reduced the expression of p21(waf1), confirming that the modulation in p21(waf1) by anti-proliferative cristacarpin was ROS dependent. Further, the elevation in p21(waf1) expression in PANC-1 and MCF-7 cells was consistent with the decrease in the expression of Cdk-2 and cyclinD1. Here, we provide evidence that cristacarpin promotes senescence in a p53-independent manner. Moreover, cristacarpin treatment induced p38MAPK, indicating the ROS-dependent activation of the MAP kinase pathway, and thus abrogates the tumor growth in mouse allograft tumor model. PMID:27246693

  6. Remodeling of chromatin structure in senescent cells and its potential impact on tumor suppression and aging

    OpenAIRE

    Adams, Peter D

    2007-01-01

    Cellular senescence is an important tumor suppression process, and a possible contributor to tissue aging. Senescence is accompanied extensive changes in chromatin structure. In particular, many senescent cells accumulate specialized domains of facultative heterochromatin, called Senescence Associated Heterochromatin Foci (SAHF), which are thought to repress expression of proliferation-promoting genes, thereby contributing to senescence-associated proliferation arrest. This article reviews ou...

  7. Anti-aromatase effect of resveratrol and melatonin on hormonal positive breast cancer cells co-cultured with breast adipose fibroblasts

    NARCIS (Netherlands)

    Chottanapund, Suthat; Van Duursen, M. B M; Navasumrit, Panida; Hunsonti, Potchanee; Timtavorn, Supatchaya; Ruchirawat, Mathuros; Van den Berg, Martin

    2014-01-01

    Targeting the estrogen pathway has been proven effective in the treatment for estrogen receptor positive breast cancer. There are currently two common groups of anti-estrogenic compounds used in the clinic; Selective Estrogen Receptor Modulators (SERMs, e.g. tamoxifen) and Selective Estrogen Enzyme

  8. Increased OXPHOS activity precedes rise in glycolytic rate in H-RasV12/E1A transformed fibroblasts that develop a Warburg phenotype

    Directory of Open Access Journals (Sweden)

    Pluk Helma

    2009-07-01

    Full Text Available Abstract Background The Warburg phenotype in cancer cells has been long recognized, but there is still limited insight in the consecutive metabolic alterations that characterize its establishment. We obtained better understanding of the coupling between metabolism and malignant transformation by studying mouse embryonic fibroblast-derived cells with loss-of-senescence or H-RasV12/E1A-transformed phenotypes at different stages of oncogenic progression. Results Spontaneous immortalization or induction of senescence-bypass had only marginal effects on metabolic profiles and viability. In contrast, H-RasV12/E1A transformation initially caused a steep increase in oxygen consumption and superoxide production, accompanied by massive cell death. During prolonged culture in vitro, cell growth rate increased gradually, along with tumor forming potential in in vitro anchorage-independent growth assays and in vivo tumor formation assays in immuno-deficient mice. Notably, glucose-to-lactic acid flux increased with passage number, while cellular oxygen consumption decreased. This conversion in metabolic properties was associated with a change in mitochondrial NAD+/NADH redox, indicative of decreased mitochondrial tricarboxic acid cycle and OXPHOS activity. Conclusion The high rate of oxidative metabolism in newly transformed cells is in marked contrast with the high glycolytic rate in cells in the later tumor stage. In our experimental system, with cells growing under ambient oxygen conditions in nutrient-rich media, the shift towards this Warburg phenotype occurred as a step-wise adaptation process associated with augmented tumorigenic capacity and improved survival characteristics of the transformed cells. We hypothesize that early-transformed cells, which potentially serve as founders for new tumor masses may escape therapies aimed at metabolic inhibition of tumors with a fully developed Warburg phenotype.

  9. Adiponectin corrects premature cellular senescence and normalizes antimicrobial peptide levels in senescent keratinocytes.

    Science.gov (United States)

    Jin, Taewon; Kim, Min Jeong; Heo, Won Il; Park, Kui Young; Choi, Sun Young; Lee, Mi-Kyung; Hong, Seung-Phil; Kim, Seong-Jin; Im, Myung; Moon, Nam Ju; Seo, Seong Jun

    2016-09-01

    Stress-induced premature senescence or aging causes dysfunction in the human somatic system. Adiponectin (Acrp30) plays a role in functional recovery, especially with adenosine 3',5'-monophosphate (AMP)-activated protein kinase (AMPK) and silent mating type information regulation 2 homolog 1 (SIRT1). Acrp30 stimulation reduced the premature senescence positive ratio induced by hydrogen peroxide (H2O2) and restituted human β-defensin 2 (hBD-2) levels in senescent keratinocytes. Acrp30 recovered AMPK activity in senescent keratinocytes and increased SIRT1 deacetylation activity. As a result, FoxO1 and FoxO3 transcription activity was recovered. Additionally, Acrp30 stimulation suppresses NFκB p65, which induces abnormal expression of hBD-2 induced by H2O2. In the present study, we have shown that Acrp30 reduces premature senescence and recovers cellular function in keratinocytes. These results suggest a role for Acrp30 as an anti-aging agent to improve impaired skin immune barriers. PMID:27349869

  10. Characterization of senescence-associated protease activities involved in the efficient protein remobilization during leaf senescence of winter oilseed rape.

    Science.gov (United States)

    Poret, Marine; Chandrasekar, Balakumaran; van der Hoorn, Renier A L; Avice, Jean-Christophe

    2016-05-01

    Oilseed rape (Brassica napus L.) is a crop plant characterized by a poor nitrogen (N) use efficiency that is mainly due to low N remobilization efficiency during the sequential leaf senescence of the vegetative stage. As a high leaf N remobilization efficiency was strongly linked to a high remobilization of proteins during leaf senescence of rapeseed, our objective was to identify senescence-associated protease activities implicated in the protein degradation. To reach this goal, leaf senescence processes and protease activities were investigated in a mature leaf becoming senescent in plants subjected to ample or low nitrate supply. The characterization of protease activities was performed by using in vitro analysis of RuBisCO degradation with or without inhibitors of specific protease classes followed by a protease activity profiling using activity-dependent probes. As expected, the mature leaf became senescent regardless of the nitrate treatment, and nitrate limitation enhanced the senescence processes associated with an enhanced degradation of soluble proteins. The characterization of protease activities revealed that: (i) aspartic proteases and the proteasome were active during senescence regardless of nitrate supply, and (ii) the activities of serine proteases and particularly cysteine proteases (Papain-like Cys proteases and vacuolar processing enzymes) increased when protein remobilization associated with senescence was accelerated by nitrate limitation. Short statement: Serine and particularly cysteine proteases (both PLCPs and VPEs) seem to play a crucial role in the efficient protein remobilization when leaf senescence of oilseed rape was accelerated by nitrate limitation. PMID:26993244

  11. Calculating the Rate of Senescence From Mortality Data

    DEFF Research Database (Denmark)

    Koopman, Jacob J E; Rozing, Maarten P; Kramer, Anneke; Abad, José M; Finne, Patrik; Heaf, James G; Hoitsma, Andries J; De Meester, Johan M J; Palsson, Runolfur; Postorino, Maurizio; Ravani, Pietro; Wanner, Christoph; Jager, Kitty J; van Bodegom, David; Westendorp, Rudi G J

    2015-01-01

    , they do not fit mortality rates at young and old ages. Therefore, we developed a method to calculate senescence rates from the acceleration of mortality directly without modeling the mortality rates. We applied the different methods to age group-specific mortality data from the European Renal...... Association-European Dialysis and Transplant Association Registry, including patients with end-stage renal disease on dialysis, who are known to suffer from increased senescence rates (n = 302,455), and patients with a functioning kidney transplant (n = 74,490). From age 20 to 70, senescence rates were...... comparable when calculated with or without a model. However, when using non-modeled mortality rates, senescence rates were yielded at young and old ages that remained concealed when using modeled mortality rates. At young ages senescence rates were negative, while senescence rates declined at old ages. In...

  12. Abnormal ultraviolet mutagenic spectrum in plasmid DNA replicated in cultured fibroblasts from a patient with the skin cancer-prone disease, xeroderma pigmentosum.

    OpenAIRE

    Seetharam, S; Protić-Sabljić, M; Seidman, M M; Kraemer, K H

    1987-01-01

    A shuttle vector plasmid, pZ189, was utilized to assess the types of mutations that cells from a patient with xeroderma pigmentosum, complementation group D, introduce into ultraviolet (UV) damaged, replicating DNA. Patients with xeroderma pigmentosum have clinical and cellular UV hypersensitivity, increased frequency of sun-induced skin cancer, and deficient DNA repair. In comparison to UV-treated pZ189 replicated in DNA repair-proficient cells, there were fewer surviving plasmids, a higher ...

  13. The PML domain of PML-RARα blocks senescence to promote leukemia.

    Science.gov (United States)

    Korf, Katharina; Wodrich, Harald; Haschke, Alexander; Ocampo, Corinne; Harder, Lena; Gieseke, Friederike; Pollmann, Annika; Dierck, Kevin; Prall, Sebastian; Staege, Hannah; Ma, Hui; Horstmann, Martin A; Evans, Ronald M; Sternsdorf, Thomas

    2014-08-19

    In most acute promyelocytic leukemia (APL) cases, translocons produce a promyelocytic leukemia protein-retinoic acid receptor α (PML-RARα) fusion gene. Although expression of the human PML fusion in mice promotes leukemia, its efficiency is rather low. Unexpectedly, we find that simply replacing the human PML fusion with its mouse counterpart results in a murine PML-RARα (mPR) hybrid protein that is transformed into a significantly more leukemogenic oncoprotein. Using this more potent isoform, we show that mPR promotes immortalization by preventing cellular senescence, impeding up-regulation of both the p21 and p19(ARF) cell-cycle regulators. This induction coincides with a loss of the cancer-associated ATRX/Daxx-histone H3.3 predisposition complex and suggests inhibition of senescence as a targetable mechanism in APL therapy. PMID:25092303

  14. The PML domain of PML–RARα blocks senescence to promote leukemia

    Science.gov (United States)

    Korf, Katharina; Wodrich, Harald; Haschke, Alexander; Ocampo, Corinne; Harder, Lena; Gieseke, Friederike; Pollmann, Annika; Dierck, Kevin; Prall, Sebastian; Staege, Hannah; Ma, Hui; Horstmann, Martin A.; Evans, Ronald M.; Sternsdorf, Thomas

    2014-01-01

    In most acute promyelocytic leukemia (APL) cases, translocons produce a promyelocytic leukemia protein–retinoic acid receptor α (PML–RARα) fusion gene. Although expression of the human PML fusion in mice promotes leukemia, its efficiency is rather low. Unexpectedly, we find that simply replacing the human PML fusion with its mouse counterpart results in a murine PML–RARα (mPR) hybrid protein that is transformed into a significantly more leukemogenic oncoprotein. Using this more potent isoform, we show that mPR promotes immortalization by preventing cellular senescence, impeding up-regulation of both the p21 and p19ARF cell-cycle regulators. This induction coincides with a loss of the cancer-associated ATRX/Daxx–histone H3.3 predisposition complex and suggests inhibition of senescence as a targetable mechanism in APL therapy. PMID:25092303

  15. Telomere-independent cellular senescence in human fetal cardiomyocytes

    OpenAIRE

    Ball, Andrew J.; Levine, F

    2005-01-01

    Fetal cardiomyocytes have been proposed as a potential source of cell-based therapy for heart failure. This study examined cellular senescence in cultured human fetal ventricular cardiomyocytes (HFCs). HFCs were isolated and identified by immunocytochemistry and RT-PCR. Cells were found to senesce after 20-25 population doublings, as determined by growth arrest, morphological changes and senescence-associated beta-galactosidase activity. Using the telomeric repeat amplification protocol assay...

  16. Delayed leaf senescence induces extreme drought tolerance in crop plants

    OpenAIRE

    Rivero, Rosa; Peleg, Zvi; Szczerba, Mark; Tumimbang, Ellen; Jauregui, Rosa N; Liu, Li; Blumwald, Eduardo

    2009-01-01

    Drought, the most prominent threat to agricultural production worldwide, accelerates leaf senescence, leading to a decrease in canopy size, loss in photosynthesis and reduced yields. On the basis of the assumption that senescence is a type of cell death program that could be inappropriately activated during drought, we hypothesized that it may be possible to enhance drought tolerance by delaying drought-induced leaf senescence through the stress-induced synthesis of cytokinins. We generated m...

  17. Mutation accumulation and the catastrophic senescence of Pacific salmon

    CERN Document Server

    Penna, T J P; Stauffer, D; Stauffer, Dietrich

    1995-01-01

    The bit-string model of biological aging is used to simulate the catastrophic senescence of Pacific Salmon. We have shown that reproduction occuring only once and at a fixed age is the only ingredient needed to explain the catastrophic senescence according the mutation accumulation theory. Several results are presented, some of them with up to 10^8 fishes, showing how the survival rates in catastrophic senescence are affected by changes in the parameters of the model.

  18. Fibroblasts induce epithelial to mesenchymal transition in breast tumor cells which is prevented by fibroblasts treatment with histamine in high concentration.

    Science.gov (United States)

    Porretti, Juliana C; Mohamad, Nora A; Martín, Gabriela A; Cricco, Graciela P

    2014-06-01

    Epithelial to mesenchymal transition (EMT) of cancer cells is an essential process in cancer progression. Cancer cells that undergone EMT loose cell-cell contacts, acquire mesenchymal properties and develop migratory and invasive abilities. In previous studies we have demonstrated that histamine may modify the invasive phenotype of pancreatic and mammary tumor cells. In this work we proposed to investigate whether histamine may also influence the interaction between tumor cells and normal fibroblasts. The potential activation of normal CCD-1059Sk fibroblasts by histamine and EMT phenotypic changes induced in MCF-7 and MDA-MB-231 breast tumor cells by the conditioned media (CM) derived from fibroblasts were evaluated. Initially, we determined the presence of H1, H2 and H4 histamine receptors and matrix metalloproteinase 2 (MMP2) mRNA in CCD-1059Sk fibroblasts. MMP2 gelatinolytic activity, cell migration and alpha-smooth muscle actin expression were increased in fibroblasts by low doses (histamine. MCF-7 cells cultured with CM from fibroblasts exhibited spindle-shaped morphology, cell spreading and cytoplasmic expression of β-catenin but there was no change in MMP2 activity and cell migration. MDA-MB-231 cells cultured with CM from fibroblasts showed a more elongated phenotype, cell spreading, cytoplasmic β-catenin, increased MMP2 activity and endogenous TGF-β1 expression, and enhanced cell migration and invasion. Notably, all these features were reversed when mammary tumor cells were cultured with CM from fibroblasts treated with 20μM histamine. In conclusion, high doses of histamine may prevent the activation of fibroblasts and also avert the EMT related changes induced in epithelial tumor cells by fibroblasts CM. PMID:24685678

  19. Sunitinib mesylate inhibits proliferation of human colonic stromal fibroblasts in vitro and in vivo *

    OpenAIRE

    Wang, Zhan-huai; Li, Qiong; Ruan, Shu-qin; Xiao, Qian; Liu, Yue; Hu, Ye-ting; Hu, Li-feng; Chen, Hai-Yan; Zheng, Shu; Zhang, Su-zhan; Ding, Ke-Feng

    2014-01-01

    Objective: Cancer stromal fibroblasts are important members of the cancer microenvironment. In this study, we determined the effect of sunitinib, a small molecule tyrosine kinase inhibitor, on the primary human colonic fibroblasts. Methods: Cell cycle analysis and cell proliferation assays were performed to evaluate the inhibitory effect of sunitinib in vitro. Western-blot analysis was performed to evaluate variations in the levels of phosphorylated platelet-derived growth factor receptor β (...

  20. Abnormal ultraviolet mutagenic spectrum in plasmid DNA replicated in cultured fibroblasts from a patient with the skin cancer-prone disease, xeroderma pigmentosum

    International Nuclear Information System (INIS)

    A shuttle vector plasmid, pZ189, was utilized to assess the types of mutations that cells from a patient with xeroderma pigmentosum, complementation group D, introduce into ultraviolet (UV) damaged, replicating DNA. Patients with xeroderma pigmentosum have clinical and cellular UV hypersensitivity, increased frequency of sun-induced skin cancer, and deficient DNA repair. In comparison to UV-treated pZ189 replicated in DNA repair-proficient cells, there were fewer surviving plasmids, a higher frequency of plasmids with mutations, fewer plasmids with two or more mutations in the marker gene, and a new mutagenic hotspot. The major type of base substitution mutation was the G:C to A:T transition with both cell lines. These results, together with similar findings published earlier with cells from a xeroderma pigmentosum patient in complementation group A, suggest that isolated G:C to A:T somatic mutations may be particularly important in generation of human skin cancer by UV radiation

  1. Role of the beta catenin destruction complex in mediating chemotherapy-induced senescence-associated secretory phenotype.

    Directory of Open Access Journals (Sweden)

    Dipanjan Basu

    Full Text Available Cellular senescence is considered as a tumor suppressive mechanism. Recent evidence indicates however that senescent cells secrete various growth factors and cytokines, some of which may paradoxically promote cancer progression. This phenomenon termed senescence-associated secretory phenotype (SASP must be inhibited in order for anti-proliferative agents to be effective. The present study was designed to determine whether the β-catenin destruction complex (BCDC, known to integrate the action of various growth factors and cytokines, would represent a suitable target to inhibit the activity of SASP components. For this, we carried out experiments to determine the effect of drug-induced senescence on secretion of SASP, β-catenin transactivation, and the relationship between these processes. Moreover, genetic and pharmacological approaches were used to define the implication of BCDC in mediating the effects of SASP components on cell migration and resistance to drugs. The findings indicate that drug-induced senescence was associated with expression of various Wnt ligands in addition to previously known SASP components. Beta catenin transactivation and expression of genes implicated in epithelial-mesenchymal transition (EMT also increased in response to drug-induced SASP. These effects were prevented by Pyrvinium, a recently described activator of BCDC. Pyrvinium also suppressed the effects of SASP on cell migration and resistance to doxorubicin. Together, these findings provide insights on the potential role of BCDC in mediating the effects of drug-induced SASP on cancer cell invasion and resistance to therapy, and suggest that targeting this pathway may represent an effective approach to enhance the activity of current and prospective anti-cancer therapeutics.

  2. Studying the Anti-aging Effect of Human Growth Hormone on Human Fibroblast Cells via Telomerase Activity

    Directory of Open Access Journals (Sweden)

    Nader Chaparzadeh

    2010-01-01

    Full Text Available Objective: In recent years, studies have focused on the telomerase for cancer treatmentby repressing telomerase in cancerous cells or prevent cell aging by activating it in theaged cells. Thus, in these studies natural and synthetic agents have been used to repressor activate telomerase. In this research, we investigated the effects of human growth hormone(hGH on aging via evaluation of telomerase activity.Materials and Methods: Primary human foreskin fibroblast cells were isolated, culturedand treated with different concentrations of hGH. BrdU and MTT cell proliferation assaysand cells number counting. Cell aging was assayed by the senescence sensitivegalactosidase staining method. Telomerase activity was measured with a telomerasePCR ELISA kit.Data were analyzed with SPSS software (one-way ANOVA and univariateANOVA.Results: Our results indicated that cells treated with a lower concentration (0.1, 1 ng/mlof hGH had more green color cells (aged cells. Furthermore, cell proliferation increasedwith increasing hGH concentrations (10 to 100 ng/ml which was significant in comparisonwith untreated control cells. TRAP assay results indicated that telomerase activityincreased with increasing hGH concentration, but there was no significant difference. Additionally,more rapid cell growth and telomerase activity was noted in the absence of H2O2when compared with the presence of H2O2, which was significantly different.Conclusion: Although increasing cell proliferation along with increasing hGH concentrationwas confirmed by all cell proliferation assays, only the cell counting test was statisticallysignificant. Thus, it is inconclusive that hGH (up to 100 ng/ml has an anti-agingeffect. Also, because there was no significant difference in the telomerase activity results(in spite of increasing progress along with increasing hGH concentration we can not certainlyconclude that hGH (up to 100 ng/ml impacts telomerase activity.

  3. MicroRNA-34a regulation of endothelial senescence

    International Nuclear Information System (INIS)

    Research highlights: → MicroRNA-34a (miR-34a) regulates senescence and cell cycle progression in endothelial cells. → MiR-34a expression increases during endothelial cell senescence and in older mice. → SIRT1 is a miR-34a target gene in endothelial cells. → SIRT1 mediates the effects of miR-34a upon cell senescence in endothelial cells. -- Abstract: Endothelial senescence is thought to play a role in cardiovascular diseases such as atherosclerosis. We hypothesized that endothelial microRNAs (miRNAs) regulate endothelial survival and senescence. We found that miR-34a is highly expressed in primary endothelial cells. We observed that miR-34a expression increases in senescent human umbilical cord vein endothelial cells (HUVEC) and in heart and spleen of older mice. MiR-34a over-expression induces endothelial cell senescence and also suppresses cell proliferation by inhibiting cell cycle progression. Searching for how miR-34a affects senescence, we discovered that SIRT1 is a target of miR-34a. Over-expressing miR-34a inhibits SIRT1 protein expression, and knocking down miR-34a enhances SIRT1 expression. MiR-34a triggers endothelial senescence in part through SIRT1, since forced expression of SIRT1 blocks the ability of miR-34a to induce senescence. Our data suggest that miR-34a contributes to endothelial senescence through suppression of SIRT1.

  4. Increased SHP-1 expression results in radioresistance, inhibition of cellular senescence, and cell cycle redistribution in nasopharyngeal carcinoma cells

    International Nuclear Information System (INIS)

    Radioresistance is the main limit to the efficacy of radiotherapy in nasopharyngeal carcinoma (NPC). SHP-1 is involved in cancer progression, but its role in radioresistance and senescence of NPC is not well understood. This study aimed to assess the role of SHP-1 in the radioresistance and senescence of NPC cells. SHP-1 was knocked-down and overexpressed in CNE-1 and CNE-2 cells using lentiviruses. Cells were irradiated to observe their radiosensitivity by colony forming assay. BrdU incorporation assay and flow cytometry were used to monitor cell cycle. A β-galactosidase assay was used to assess senescence. Western blot was used to assess SHP-1, p21, p53, pRb, Rb, H3K9Me3, HP1γ, CDK4, cyclin D1, cyclin E, and p16 protein expressions. Compared with CNE-1-scramble shRNA cells, SHP-1 downregulation resulted in increased senescence (+107 %, P < 0.001), increased radiosensitivity, higher proportion of cells in G0/G1 (+33 %, P < 0.001), decreased expressions of CDK4 (−44 %, P < 0.001), cyclin D1 (−41 %, P = 0.001), cyclin E (−97 %, P < 0.001), Rb (−79 %, P < 0.001), and pRb (−76 %, P = 0.001), and increased expression of p16 (+120 %, P = 0.02). Furthermore, SHP-1 overexpression resulted in radioresistance, inhibition of cellular senescence, and cell cycle arrest in the S phase. Levels of p53 and p21 were unchanged in both cell lines (all P > 0.05). SHP-1 has a critical role in radioresistance, cell cycle progression, and senescence of NPC cells. Down-regulating SHP-1 may be a promising therapeutic approach for treating patients with NPC

  5. Expression of the senescence marker p16INK4a in skin biopsies of acute lymphoblastic leukemia survivors: a pilot study

    International Nuclear Information System (INIS)

    Most childhood cancer survivors will develop ionizing radiation treatment-related health conditions that, in many instances, resemble age-associated pathologies. Treatment-induced premature senescence could be an underlying mechanism. Here we wanted to know whether the expression of p16INK4a, a senescence/aging biomarker, is increased in skin biopsies of acute lymphoblastic leukemia survivors (ALL), previously exposed to chemotherapy and radiation therapy. Several years post-treatments, we found p16INK4a mRNA levels are 5.8 times higher in scalp skin biopsies (targeted by cranial irradiation therapy) compared to buttocks skin biopsies (n = 10, p = 0.01). These results demonstrate for the first time that premature senescence is induced in pediatric cancer survivors and that p16INK4a expression could be used as a potential biomarker in this population

  6. Senescence and programmed cell death : substance or semantics?

    NARCIS (Netherlands)

    Doorn, van W.G.; Woltering, E.J.

    2004-01-01

    The terms senescence and programmed cell death (PCD) have led to some confusion. Senescence as visibly observed in, for example, leaf yellowing and petal wilting, has often been taken to be synonymous with the programmed death of the constituent cells. PCD also obviously refers to cells, which show

  7. The Pace and Shape of Senescence in Angiosperms

    DEFF Research Database (Denmark)

    Baudisch, Annette; Salguero-Gómez, Roberto; Jones, Owen; Wrycza, Tomasz; Mbeau-Ache, Cyril; Franco, Miguel; Colchero, Fernando

    2013-01-01

    phylogenetic relationships using a resolved supertree. 4. In contrast to the animal kingdom, most angiosperms (93%) show no senescence. Senescence is observed among phanerophytes (i.e. trees), but not among any other growth form (e.g. epiphytes, chamaephytes or cryptopyhtes). Yet, most phanerophytes (81%) do...

  8. Global Reorganization of the Nuclear Landscape in Senescent Cells

    Directory of Open Access Journals (Sweden)

    Tamir Chandra

    2015-02-01

    Full Text Available Cellular senescence has been implicated in tumor suppression, development, and aging and is accompanied by large-scale chromatin rearrangements, forming senescence-associated heterochromatic foci (SAHF. However, how the chromatin is reorganized during SAHF formation is poorly understood. Furthermore, heterochromatin formation in senescence appears to contrast with loss of heterochromatin in Hutchinson-Gilford progeria. We mapped architectural changes in genome organization in cellular senescence using Hi-C. Unexpectedly, we find a dramatic sequence- and lamin-dependent loss of local interactions in heterochromatin. This change in local connectivity resolves the paradox of opposing chromatin changes in senescence and progeria. In addition, we observe a senescence-specific spatial clustering of heterochromatic regions, suggesting a unique second step required for SAHF formation. Comparison of embryonic stem cells (ESCs, somatic cells, and senescent cells shows a unidirectional loss in local chromatin connectivity, suggesting that senescence is an endpoint of the continuous nuclear remodelling process during differentiation.

  9. Cellular and molecular aspects of quinoa leaf senescence.

    Science.gov (United States)

    López-Fernández, María Paula; Burrieza, Hernán Pablo; Rizzo, Axel Joel; Martínez-Tosar, Leandro Julián; Maldonado, Sara

    2015-09-01

    During leaf senescence, degradation of chloroplasts precede to changes in nuclei and other cytoplasmic organelles, RuBisCO stability is progressively lost, grana lose their structure, plastidial DNA becomes distorted and degraded, the number of plastoglobuli increases and abundant senescence-associated vesicles containing electronically dense particles emerge from chloroplasts pouring their content into the central vacuole. This study examines quinoa leaf tissues during development and senescence using a range of well-established markers of programmed cell death (PCD), including: morphological changes in nuclei and chloroplasts, degradation of RuBisCO, changes in chlorophyll content, DNA degradation, variations in ploidy levels, and changes in nuclease profiles. TUNEL reaction and DNA electrophoresis demonstrated that DNA fragmentation in nuclei occurs at early senescence, which correlates with induction of specific nucleases. During senescence, metabolic activity is high and nuclei endoreduplicate, peaking at 4C. At this time, TEM images showed some healthy nuclei with condensed chromatin and nucleoli. We have found that DNA fragmentation, induction of senescence-associated nucleases and endoreduplication take place during leaf senescence. This provides a starting point for further research aiming to identify key genes involved in the senescence of quinoa leaves. PMID:26259186

  10. Senescence vs. sustenance: Evolutionary-demographic models of aging

    OpenAIRE

    Annette Baudisch; James Vaupel

    2010-01-01

    Humans, and many other species, suffer senescence: mortality increases and fertility declines with adult age. Some species, however, enjoy sustenance: mortality and fertility remain constant. Here we develop simple but general evolutionary-demographic models to explain the conditions that favor senescence vs. sustenance. The models illustrate how mathematical demography can deepen understanding of the evolution of aging.

  11. Emerging roles of lncRNAs in senescence

    DEFF Research Database (Denmark)

    Montes Resano, Marta; Lund, Anders H

    2016-01-01

    Cellular senescence is a complex stress response that leads to an irreversible state of cell growth arrest. Senescence may be induced by different stimuli such as telomere shortening, DNA damage or oncogenic insult among others. Senescent cells are metabolically highly active producing a wealth of...... cytokines and chemokines that depending on the context may have a beneficial or deleterious impact on the organism. Senescence is considered a tightly regulated stress response that is largely governed by the p53/p21 and p16/Rb pathways. Many molecules have been identified as regulators of these two...... current knowledge of the mechanistic roles of lncRNAs affecting the main senescence pathways and discuss the importance of identifying new regulators. This article is protected by copyright. All rights reserved....

  12. TNF-{alpha} similarly induces IL-6 and MCP-1 in fibroblasts from colorectal liver metastases and normal liver fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Lars, E-mail: lars.mueller@uksh-kiel.de [Department of General and Thoracic Surgery, University Hospital of Schleswig-Holstein (Germany); Seggern, Lena von [Department of Hepatobiliary Surgery and Solid Organ Transplantation, University Hospital Hamburg-Eppendorf, Hamburg (Germany); Schumacher, Jennifer; Goumas, Freya; Wilms, Christian; Braun, Felix; Broering, Dieter C. [Department of General and Thoracic Surgery, University Hospital of Schleswig-Holstein (Germany)

    2010-07-02

    Cancer-associated fibroblasts (CAFs) represent the predominant cell type of the neoplastic stroma of solid tumors, yet their biology and functional specificity for cancer pathogenesis remain unclear. We show here that primary CAFs from colorectal liver metastases express several inflammatory, tumor-enhancing factors, including interleukin (IL)-6 and monocyte-chemoattractant protein (MCP)-1. Both molecules were intensely induced by TNF-{alpha} on the transcript and protein level, whereas PDGF-BB, TGF-{beta}1 and EGF showed no significant effects. To verify their potential specialization for metastasis progression, CAFs were compared to fibroblasts from non-tumor liver tissue. Interestingly, these liver fibroblasts (LFs) displayed similar functions. Further analyses revealed a comparable up-regulation of intercellular adhesion molecule-1 (ICAM-1) by TNF-{alpha}, and of alpha-smooth muscle actin, by TGF-{beta}1. Moreover, the proliferation of both cell types was induced by PDGF-BB, and CAFs and LFs displayed an equivalent migration towards HT29 colon cancer cells in Boyden chamber assays. In conclusion, colorectal liver metastasis may be supported by CAFs and resident fibroblastic cells competent to generate a prometastatic microenvironment through inflammatory activation of IL-6 and MCP-1.

  13. The H3K27me3 demethylase JMJD3 contributes to the activation of the INK4A-ARF locus in response to oncogene- and stress-induced senescence

    DEFF Research Database (Denmark)

    Agger, Karl; Cloos, Paul A C; Rudkjaer, Lise;

    2009-01-01

    The tumor suppressor proteins p16INK4A and p14ARF, encoded by the INK4A-ARF locus, are key regulators of cellular senescence. The locus is epigenetically silenced by the repressive H3K27me3 mark in normally growing cells, but becomes activated in response to oncogenic stress. Here, we show that e...... mouse embryonic fibroblasts results in suppression of p16Ink4a and p19Arf expression and in their immortalization....

  14. Transcription Factor ATAF1 in Arabidopsis Promotes Senescence by Direct Regulation of Key Chloroplast Maintenance and Senescence Transcriptional Cascades.

    Science.gov (United States)

    Garapati, Prashanth; Xue, Gang-Ping; Munné-Bosch, Sergi; Balazadeh, Salma

    2015-07-01

    Senescence represents a fundamental process of late leaf development. Transcription factors (TFs) play an important role for expression reprogramming during senescence; however, the gene regulatory networks through which they exert their functions, and their physiological integration, are still largely unknown. Here, we identify the Arabidopsis (Arabidopsis thaliana) abscisic acid (ABA)- and hydrogen peroxide-activated TF Arabidopsis thaliana activating factor1 (ATAF1) as a novel upstream regulator of senescence. ATAF1 executes its physiological role by affecting both key chloroplast maintenance and senescence-promoting TFs, namely GOLDEN2-LIKE1 (GLK1) and ORESARA1 (Arabidopsis NAC092), respectively. Notably, while ATAF1 activates ORESARA1, it represses GLK1 expression by directly binding to their promoters, thereby generating a transcriptional output that shifts the physiological balance toward the progression of senescence. We furthermore demonstrate a key role of ATAF1 for ABA- and hydrogen peroxide-induced senescence, in accordance with a direct regulatory effect on ABA homeostasis genes, including nine-CIS-epoxycarotenoid dioxygenase3 involved in ABA biosynthesis and ABC transporter G family member40, encoding an ABA transport protein. Thus, ATAF1 serves as a core transcriptional activator of senescence by coupling stress-related signaling with photosynthesis- and senescence-related transcriptional cascades. PMID:25953103

  15. Arabidopsis CPR5 is a senescence-regulatory gene with pleiotropic functions as predicted by the evolutionary theory of senescence

    NARCIS (Netherlands)

    Jing, Hai-Chun; Anderson, Lisa; Sturre, Marcel J. G.; Hille, Jacques; Dijkwel, Paul P.

    2007-01-01

    Arabidopsis CPR5 is a senescence-regulatory gene with pleiotropic functions as predicted by the evolutionary theory of senescence Hai-Chun Jing1,2, Lisa Anderson3, Marcel J.G. Sturre1, Jacques Hille1 and Paul P. Dijkwel1,* 1Molecular Biology of Plants, Groningen Biomolecular Sciences and Biotechnolo

  16. REDD1 protects osteoblast cells from gamma radiation-induced premature senescence.

    Directory of Open Access Journals (Sweden)

    Xiang Hong Li

    Full Text Available Radiotherapy is commonly used for cancer treatment. However, it often results in side effects due to radiation damage in normal tissue, such as bone marrow (BM failure. Adult hematopoietic stem and progenitor cells (HSPC reside in BM next to the endosteal bone surface, which is lined primarily by hematopoietic niche osteoblastic cells. Osteoblasts are relatively more radiation-resistant than HSPCs, but the mechanisms are not well understood. In the present study, we demonstrated that the stress response gene REDD1 (regulated in development and DNA damage responses 1 was highly expressed in human osteoblast cell line (hFOB cells after γ irradiation. Knockdown of REDD1 with siRNA resulted in a decrease in hFOB cell numbers, whereas transfection of PCMV6-AC-GFP-REDD1 plasmid DNA into hFOB cells inhibited mammalian target of rapamycin (mTOR and p21 expression and protected these cells from radiation-induced premature senescence (PS. The PS in irradiated hFOB cells were characterized by significant inhibition of clonogenicity, activation of senescence biomarker SA-β-gal, and the senescence-associated cytokine secretory phenotype (SASP after 4 or 8 Gy irradiation. Immunoprecipitation assays demonstrated that the stress response proteins p53 and nuclear factor κ B (NFkB interacted with REDD1 in hFOB cells. Knockdown of NFkB or p53 gene dramatically suppressed REDD1 protein expression in these cells, indicating that REDD1 was regulated by both factors. Our data demonstrated that REDD1 is a protective factor in radiation-induced osteoblast cell premature senescence.

  17. Single Exposure of Human Oral Mucosa Fibroblasts to Ultraviolet B Radiation Reduces Proliferation and Induces COX-2 Expression and Activation

    Directory of Open Access Journals (Sweden)

    Y Boza

    2010-12-01

    Full Text Available The lip vermillion constitutes a transition tissue, between oral mucosa and skin, where oral mucosal cells from epithelial and connective tissue compartments are exposed to ultraviolet (UV sunlight. Fibroblasts are abundant resident cells of the connective tissue which are key regulators of extracellular matrix composition, as well as, epithelial and endothelial cell function. UVB light, an inherent component of sunlight, causes several alterations in skin fibroblasts, including premature senescence and increased cyclooxygenase (COX-2 expression. To assess if UVB irradiation had similar effects on fibroblasts derived from human oral mucosa (HOM, primary cultures of HOM fibroblasts were irradiated with a single dose of 30 or 60 mJ/cm²of UVB light or sham-irradiated. Fibroblast proliferation was assessed from 3 to 48 hrs after UVB-irradiation utilizing [³H]-thymidine incorporation and MTT assays. In addition, COX-2 mRNA expression was detected by RT-PCR, and PGE2 production was assessed using enzyme immunoassay from 0.5 to 24 hrs after UVB-irradiation. The results showed a significant decrease in proliferation of UVB-irradiated HOM fibroblasts as compared to controls as measured by both [³H]-thymidine incorporation and MTT assays (p<0.001. HOM fibroblasts had increased COX-2 mRNA expression at 0.5 and 12 hrs after irradiation, and PGE2 production was elevated at 12 and 24 hrs post-irradiation as compared to controls (p<0.05. The results showed an inhibitory effect of a single dose of UVB irradiation on HOM fibroblast proliferation with an increase in COX-2 expression and activation. Therefore, photodamaged fibroblasts may play and important role in the pathogenesis of UV-induced lesions of the lip.

  18. COH-203, a novel microtubule inhibitor, exhibits potent anti-tumor activity via p53-dependent senescence in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Huan; Zuo, Dai-Ying; Bai, Zhao-Shi; Xu, Jing-Wen; Li, Zeng-Qiang [Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang (China); Shen, Qi-Rong; Wang, Zhi-Wei [Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang (China); Zhang, Wei-Ge, E-mail: zhangweige2000@sina.com [Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang (China); Wu, Ying-Liang, E-mail: yingliang_1016@163.com [Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang (China)

    2014-12-12

    Highlights: • COH-203 exhibits anti-hepatoma effects in vitro and in vivo with low toxicity. • COH-203 inhibits tubulin polymerization. • COH-203 induces mitotic arrest followed by mitotic slippage in BEL-7402 cells. • COH-203 induces p53-dependent senescence in BEL-7402 cells. - Abstract: 5-(3-Hydroxy-4-methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)-3H-1, 2-dithiol-3-one (COH-203) is a novel synthesized analogue of combretastatin A-4 that can be classified as a microtubule inhibitor. In this study, we evaluated the anti-hepatoma effect of COH-203 in vitro and in vivo and explored the underlying molecular mechanisms. COH-203 was shown to be more effective in inhibiting the proliferation of liver cancer cells compared with normal liver cells. COH-203 also displayed potent anti-tumor activity in a hepatocellular carcinoma xenograft model without significant toxicity. Mechanistic studies demonstrated that treatment with COH-203 induced mitotic arrest by inhibiting tubulin polymerization in BEL-7402 liver cancer cells. Long-term COH-203 treatment in BEL-7402 cells led to mitotic slippage followed by senescence via the p14{sup Arf}–p53–p21 and p16{sup INK4α}–Rb pathways. Furthermore, suppression of p53 via pifithrin-α (p53 inhibitor) and p53-siRNA attenuated COH-203-induced senescence in BEL-7402 cells, suggesting that COH-203 induced senescence p53-dependently. In conclusion, we report for the first time that COH-203, one compound in the combretastatin family, promotes anti-proliferative activity through the induction of p-53 dependent senescence. Our findings will provide a molecular rationale for the development of COH-203 as a promising anti-tumor agent.

  19. The time-pattern of rises and falls in proliferation fades with senescence of mortal lines and is perpetuated in immortal rat hepatoma Fao cell line.

    Science.gov (United States)

    Maigné, J; Deschatrette, J; Sarrazin, S; Hecquet, B; Guerroui, S; Wolfrom, C

    1998-02-01

    Immortal cells perpetuate the rises and falls of proliferation that are progressively damped in mortal long-term cultured cells. For immortal rat hepatoma Fao cells, similar waves of proliferation occurred about every 3-4 wk. Under the same conditions, embryonic human fibroblasts and transformed but not immortalized embryonic fibroblasts display similarly recurring proliferation waves that progressively decrease in amplitude until senescence of the lines. In addition, strains of diploid normal human skin fibroblasts cultured under different culture conditions display a similar time-pattern of proliferation. Although the amplitude and baseline of these fluctuations are characteristic for each cell line, a common point was marked slow down in proliferation after every sequence of about 25 population doublings for all cells. Renewed proliferation waves of Fao cells allow about 22-23 additional population doublings each. Normal embryonic fibroblast culture and its transformed counterpart accumulate about 30 and 60 population doublings, respectively, before senescence. Normal fibroblast strains accumulate about 25 population doublings over their entire life spans. This halt in proliferation after every stretch of about 25 population doublings may correspond to a structural or functional stop following attrition of telomeric DNA. This putative stop may be bypassed once in transformed embryonic cells and repetitively in immortal cells. In support of this hypothesis, we observed rapid telomere shortening, in two steps, during divisions of mortal embryonic cells, and maintenance of long telomeres in immortal Fao cells, which may indicate episodic repair of telomeres. Alternatively, such maintenance of long telomeres may reflect survival and successive clonal growth of rare cells with long telomeres. We suggest that the balance between telomere attrition and repair processes regulates the waves of proliferation. PMID:9542655

  20. Overexpression of HDAC1 induces cellular senescence by Sp1/PP2A/pRb pathway

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Jian-Ying [Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan (China); Hung, Jan-Jong, E-mail: petehung@mail.ncku.edu.tw [Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan (China); Institute of Bioinformatics and Biosignal Transduction, National Cheng-Kung University, Tainan 701, Taiwan (China)

    2011-04-15

    Highlights: {yields} Overexpression of HDAC1 induces Sp1 deacetylation and raises Sp1/p300 complex formation to bind to PP2Ac promoter. {yields} Overexpression of HDAC1 strongly inhibits the phosphorylation of pRb through up-regulation of PP2A. {yields} Overexpressed HDAC1 restrains cell proliferaction and induces cell senescence though a novel Sp1/PP2A/pRb pathway. -- Abstract: Senescence is associated with decreased activities of DNA replication, protein synthesis, and cellular division, which can result in deterioration of cellular functions. Herein, we report that the growth and division of tumor cells were significantly repressed by overexpression of histone deacetylase (HDAC) 1 with the Tet-off induced system or transient transfection. In addition, HDAC1 overexpression led to senescence through both an accumulation of hypophosphorylated active retinoblastoma protein (pRb) and an increase in the protein level of protein phosphatase 2A catalytic subunit (PP2Ac). HDAC1 overexpression also increased the level of Sp1 deacetylation and elevated the interaction between Sp1 and p300, and subsequently that Sp1/p300 complex bound to the promoter of PP2Ac, thus leading to induction of PP2Ac expression. Similar results were obtained in the HDAC1-Tet-off stable clone. Taken together, these results indicate that HDAC1 overexpression restrained cell proliferation and induced premature senescence in cervical cancer cells through a novel Sp1/PP2A/pRb pathway.

  1. Endothelial cell senescence is associated with disrupted cell-cell junctions and increased monolayer permeability

    Directory of Open Access Journals (Sweden)

    Krouwer Vincent J D

    2012-08-01

    Full Text Available Abstract Background Cellular senescence is associated with cellular dysfunction and has been shown to occur in vivo in age-related cardiovascular diseases such as atherosclerosis. Atherogenesis is accompanied by intimal accumulation of LDL and increased extravasation of monocytes towards accumulated and oxidized LDL, suggesting an affected barrier function of vascular endothelial cells. Our objective was to study the effect of cellular senescence on the barrier function of non-senescent endothelial cells. Methods Human umbilical vein endothelial cells were cultured until senescence. Senescent cells were compared with non-senescent cells and with co-cultures of non-senescent and senescent cells. Adherens junctions and tight junctions were studied. To assess the barrier function of various monolayers, assays to measure permeability for Lucifer Yellow (LY and horseradish peroxidase (PO were performed. Results The barrier function of monolayers comprising of senescent cells was compromised and coincided with a change in the distribution of junction proteins and a down-regulation of occludin and claudin-5 expression. Furthermore, a decreased expression of occludin and claudin-5 was observed in co-cultures of non-senescent and senescent cells, not only between senescent cells but also along the entire periphery of non-senescent cells lining a senescent cell. Conclusions Our findings show that the presence of senescent endothelial cells in a non-senescent monolayer disrupts tight junction morphology of surrounding young cells and increases the permeability of the monolayer for LY and PO.

  2. MicroRNA miR-125b induces senescence in human melanoma cells

    DEFF Research Database (Denmark)

    Glud, Martin; Manfé, Valentina; Biskup, Edyta; Holst, Line; Dirksen, Anne Marie Ahlburg; Hastrup, Nina; Nielsen, Finn C; Drzewiecki, Krzysztof T; Gniadecki, Robert

    2011-01-01

    MicroRNAs (miRNAs) are small noncoding RNA molecules involved in gene regulation. Aberrant expression of miRNA has been associated with the development or progression of several diseases, including cancer. In a previous study, we found that the expression of miRNA-125b (miR-125b) was two-fold lower...... in malignant melanoma producing lymph node micrometastases than in nonmetastasizing tumors. To get further insight into the functional role of miR-125b, we assessed whether its overexpression or silencing affects apoptosis, proliferation, or senescence in melanoma cell lines. We showed that...

  3. [Contribution to tumor escape and chemotherapy response: A choice between senescence and apoptosis in heterogeneous tumors].

    Science.gov (United States)

    Jonchère, Barbara; Vétillard, Alexandra; Toutain, Bertrand; Guette, Catherine; Coqueret, Olivier

    2016-01-01

    Understanding adaptive signaling pathways in response to chemotherapy is one of the main challenges of cancer treatment. Activated in response to DNA damage, cell cycle and mitotic checkpoints activate the p53-p21 and p16-Rb pathways and induce apoptosis or senescence. Since senescent cells survive and produce a secretome that influences neighbouring cells, it is not particularly clear whether these responses are equivalent and if tumor cells escape these two suppressive pathways to the same extent. Predicting escape is also complicated by the fact that cancer cells adapt to treatments by activating the epithelial-mesenchymal transition and by producing clones with cancer-initiating cells features. Dedifferentiation pathways used in stressful conditions reconstitute dividing and sometimes more aggressive populations in response to chemotherapy. These observations illustrate the importance of tumor heterogeneity and the adaptation capacities of different intra-tumoral subclones. Depending on their oncogenic profile, on their localisation within the tumor and on their interaction with stromal cells, these subclones are expected to have different responses and adaptation capacities to chemotherapy. A complete eradication will certainly rely on combination therapies that can kill at the same time the bulk of the sensitive tumor but can also prevent plasticity and the generation of persistent clones. PMID:26762946

  4. Regulation of Leaf Senescence and Crop Genetic Improvement

    Institute of Scientific and Technical Information of China (English)

    Xiao-Yuan Wu; Ben-Ke Kuai; Ji-Zeng Jia; Hai-Chun Jing

    2012-01-01

    Leaf senescence can impact crop production by either changing photosynthesis duration,or by modifying the nutrient remobilization efficiency and harvest index.The doubling of the grain yield in major cereals in the last 50 years was primarily achieved through the extension of photosynthesis duration and the increase in crop biomass partitioning,two things that are intrinsically coupled with leaf senescence.In this review,we consider the functionality of a leaf as a function of leaf age,and divide a leaf's life into three phases:the functionality increasing phase at the early growth stage,the full functionality phase,and the senescence and functionality decreasing phase.A genetic framework is proposed to describe gene actions at various checkpoints to regulate leaf development and senescence.Four categories of genes contribute to crop production:those which regulate (Ⅰ) the speed and transition of early leaf growth,(Ⅱ) photosynthesis rate,(Ⅲ) the onset and (Ⅳ) the progression of leaf senescence.Current advances in isolating and characterizing senescence regulatory genes are discussed in the leaf aging and crop production context.We argue that the breeding of crops with leaf senescence ideotypes should be an essential part of further crop genetic improvement.

  5. Shifting p53-induced senescence to cell death by TIS21(/BTG2/Pc3) gene through posttranslational modification of p53 protein.

    Science.gov (United States)

    Choi, Ok Ran; Ryu, Min Sook; Lim, In Kyoung

    2016-09-01

    Cellular senescence and apoptosis can be regulated by p53 activity, although the underlying mechanism of the switch between the two events remains largely unknown. Cells exposed to cancer chemotherapy can escape to senescence phenotype rather than undergoing apoptosis. By employing adenoviral transduction of p53 or TIS21 genes, we observed shifting of p53 induced-senescence to apoptosis in EJ bladder cancer cells, which express H-RasV12 and mutant p53; transduction of p53 increased H-RasV12 expression along with senescence phenotypes, whereas coexpression with TIS21 (p53+TIS21) induced cell death rather than senescence. The TIS21-mediated switch of senescence to apoptosis was accompanied by nuclear translocation of p53 protein and its modifications on Ser-15 and Ser-46 phosphorylation and acetylations on Lys-120, -320, -373 and -382 residues. Mechanistically, TIS21(/BTG2) regulated posttranslational modification of p53 via enhancing miR34a and Bax expressions as opposed to inhibiting SIRT1 and Bcl2 expression. At the same time, TIS21 increased APAF-1 and p53AIP1 expressions, but inhibited the interaction of p53 with iASPP. In vitro tumorigenicity was significantly reduced in the p53+TIS21 expresser through inhibiting micro-colony proliferation by TIS21. Effect of TIS21 on the regulation of p53 activity was confirmed by knockdown of TIS21 expression by RNA interference. Therefore, we suggest TIS21 expression as an endogenous cell death inducer at the downstream of p53 gene, which might be useful for intractable cancer chemotherapy. PMID:27208501

  6. Proteolytic activity during senescence of plants

    Science.gov (United States)

    Huffaker, R. C.

    1990-01-01

    Although information has rapidly developed concerning the intracellular localization of plant proteins, relatively few reports concern the intracellular location of endo- and exo-proteolytic activities. Relatively few proteases have been purified, characterized, and associated with a specific cellular location. With the exception of the processing proteases involved in transport of proteins across membranes, little progress has yet been made concerning determination of in vivo products of specific proteases. Information on the turnover of individual proteins and the assessment of rate-limiting steps in pathways as proteins are turned over is steadily appearing. Since chloroplasts are the major site of both protein synthesis and, during senescence, degradation, it was important to show unambiguously that chloroplasts can degrade their own constituents. Another important contribution was to obtain evidence that the chloroplasts contain proteases capable of degrading their constituents. This work has been more tenuous because of the low activities found and the possibility of contamination by vacuolar enzymes during the isolation of organelles. The possible targeting of cytoplasmic proteins for degradation by facilitating their transport into vacuoles is a field which hopefully will develop more rapidly in the future. Information on targeting of proteins for degradation via the ubiquitin (Ub) degradation pathway is developing rapidly. Future research must determine how much unity exists across the different eukaryotic systems. At present, it has important implications for protein turnover in plants, since apparently Ub is involved in the degradation of phytochrome. Little information has been developed regarding what triggers increased proteolysis with the onset of senescence, although it appears to involve protein synthesis. Thus far, the evidence indicates that the complement of proteases prior to senescence is sufficient to carry out the observed protein

  7. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation

    OpenAIRE

    Xurui Zhang; Caiyong Ye; Fang Sun; Wenjun Wei; Burong Hu; Jufang Wang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92-1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. ...

  8. Co-culture of 3D tumor spheroids with fibroblasts as a model for epithelial–mesenchymal transition in vitro

    International Nuclear Information System (INIS)

    Epithelial–mesenchymal transition (EMT) acts as a facilitator of metastatic dissemination in the invasive margin of malignant tumors where active tumor–stromal crosstalks take place. Co-cultures of cancer cells with cancer-associated fibroblasts (CAFs) are often used as in vitro models of EMT. We established a tumor–fibroblast proximity co-culture using HT-29 tumor spheroids (TSs) with CCD-18co fibroblasts. When co-cultured with TSs, CCD-18co appeared activated, and proliferative activity as well as cell migration increased. Expression of fibronectin increased whereas laminin and type I collagen decreased in TSs co-cultured with fibroblasts compared to TSs alone, closely resembling the margin of in vivo xenograft tissue. Active TGFβ1 in culture media significantly increased in TS co-cultures but not in 2D co-cultures of cancer cells–fibroblasts, indicating that 3D context-associated factors from TSs may be crucial to crosstalks between cancer cells and fibroblasts. We also observed in TSs co-cultured with fibroblasts increased expression of α-SMA, EGFR and CTGF; reduced expression of membranous β-catenin and E-cadherin, together suggesting an EMT-like changes similar to a marginal region of xenograft tissue in vivo. Overall, our in vitro TS–fibroblast proximity co-culture mimics the EMT-state of the invasive margin of in vivo tumors in early metastasis. - Highlights: • An adjacent co-culture of tumor spheroids and fibroblasts is presented as EMT model. • Activation of fibroblasts and increased cell migration were shown in co-culture. • Expression of EMT-related factors in co-culture was similar to that in tumor tissue. • Crosstalk between spheroids and fibroblasts was demonstrated by secretome analysis

  9. Co-culture of 3D tumor spheroids with fibroblasts as a model for epithelial–mesenchymal transition in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun-Ah, E-mail: j.sarah.k@gmail.com [Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Lee, Eun Kyung, E-mail: leeek@catholic.ac.kr [Department of Biochemistry, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Cancer Evolution Research Center, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Kuh, Hyo-Jeong, E-mail: hkuh@catholic.ac.kr [Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Cancer Evolution Research Center, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of)

    2015-07-15

    Epithelial–mesenchymal transition (EMT) acts as a facilitator of metastatic dissemination in the invasive margin of malignant tumors where active tumor–stromal crosstalks take place. Co-cultures of cancer cells with cancer-associated fibroblasts (CAFs) are often used as in vitro models of EMT. We established a tumor–fibroblast proximity co-culture using HT-29 tumor spheroids (TSs) with CCD-18co fibroblasts. When co-cultured with TSs, CCD-18co appeared activated, and proliferative activity as well as cell migration increased. Expression of fibronectin increased whereas laminin and type I collagen decreased in TSs co-cultured with fibroblasts compared to TSs alone, closely resembling the margin of in vivo xenograft tissue. Active TGFβ1 in culture media significantly increased in TS co-cultures but not in 2D co-cultures of cancer cells–fibroblasts, indicating that 3D context-associated factors from TSs may be crucial to crosstalks between cancer cells and fibroblasts. We also observed in TSs co-cultured with fibroblasts increased expression of α-SMA, EGFR and CTGF; reduced expression of membranous β-catenin and E-cadherin, together suggesting an EMT-like changes similar to a marginal region of xenograft tissue in vivo. Overall, our in vitro TS–fibroblast proximity co-culture mimics the EMT-state of the invasive margin of in vivo tumors in early metastasis. - Highlights: • An adjacent co-culture of tumor spheroids and fibroblasts is presented as EMT model. • Activation of fibroblasts and increased cell migration were shown in co-culture. • Expression of EMT-related factors in co-culture was similar to that in tumor tissue. • Crosstalk between spheroids and fibroblasts was demonstrated by secretome analysis.

  10. Poldip2 knockout results in perinatal lethality, reduced cellular growth and increased autophagy of mouse embryonic fibroblasts.

    Directory of Open Access Journals (Sweden)

    David I Brown

    Full Text Available Polymerase-δ interacting protein 2 (Poldip2 is an understudied protein, originally described as a binding partner of polymerase delta and proliferating cell nuclear antigen (PCNA. Numerous roles for Poldip2 have been proposed, including mitochondrial elongation, DNA replication/repair and ROS production via Nox4. In this study, we have identified a novel role for Poldip2 in regulating the cell cycle. We used a Poldip2 gene-trap mouse and found that homozygous animals die around the time of birth. Poldip2-/- embryos are significantly smaller than wild type or heterozygous embryos. We found that Poldip2-/- mouse embryonic fibroblasts (MEFs exhibit reduced growth as measured by population doubling and growth curves. This effect is not due to apoptosis or senescence; however, Poldip2-/- MEFs have higher levels of the autophagy marker LC3b. Measurement of DNA content by flow cytometry revealed an increase in the percentage of Poldip2-/- cells in the G1 and G2/M phases of the cell cycle, accompanied by a decrease in the percentage of S-phase cells. Increases in p53 S20 and Sirt1 were observed in passage 2 Poldip2-/- MEFs. In passage 4/5 MEFs, Cdk1 and CyclinA2 are downregulated in Poldip2-/- cells, and these changes are reversed by transfection with SV40 large T-antigen, suggesting that Poldip2 may target the E2F pathway. In contrast, p21CIP1 is increased in passage 4/5 Poldip2-/- MEFs and its expression is unaffected by SV40 transfection. Overall, these results reveal that Poldip2 is an essential protein in development, and underline its importance in cell viability and proliferation. Because it affects the cell cycle, Poldip2 is a potential novel target for treating proliferative conditions such as cancer, atherosclerosis and restenosis.

  11. Transcriptional profile of genes involved in ascorbate glutathione cycle in senescing leaves for an early senescence leaf (esl) rice mutant.

    Science.gov (United States)

    Li, Zhaowei; Su, Da; Lei, Bingting; Wang, Fubiao; Geng, Wei; Pan, Gang; Cheng, Fangmin

    2015-03-15

    To clarify the complex relationship between ascorbate-glutathione (AsA-GSH) cycle and H2O2-induced leaf senescence, the genotype-dependent difference in some senescence-related physiological parameters and the transcript levels and the temporal patterns of genes involved in the AsA-GSH cycle during leaf senescence were investigated using two rice genotypes, namely, the early senescence leaf (esl) mutant and its wild type. Meanwhile, the triggering effect of exogenous H2O2 on the expression of OsAPX genes was examined using detached leaves. The results showed that the esl mutant had higher H2O2 level than its wild type at the initial stage of leaf senescence. At transcriptional level, the association of expression of various genes involved in the AsA-GSH cycle with leaf senescence was isoform dependent. For OsAPXs, the transcripts of two cytosolic OsAPX genes (OsAPX1 and OsAPX2), thylakoid-bound OsAPX8, chloroplastic OsAPX7 and peroxisomal OsAPX4 exhibited remarkable genotype-dependent variation in their expression levels and temporal patterns during leaf senescence, there were significantly increasing transcripts of OsAXP1 and OsAPX7, severely repressed transcripts of OsAPX4 and OsAPX8 for the esl rice at the initial leaf senescence. In contrast, the repressing transcript of OsAPX8 was highly sensitive to the increasing H2O2 level in the senescing rice leaves, while higher H2O2 concentration resulted in the enhancing transcripts of two cytosolic OsAPX genes, OsAPX7 transcript was greatly variable with different H2O2 concentrations and incubating duration, suggesting that the different OsAPXs isoforms played a complementary role in perceiving and scavenging H2O2 accumulation at various H2O2 concentrations during leaf senescence. Higher H2O2 level, increased AsA level, higher activities of APX and glutathione reductase (GR), and relatively stable GSH content during the entire sampling period in the leaves of esl mutant implied that a close interrelationship existed

  12. Senescent vs. non-senescent cells in the human annulus in vivo: Cell harvest with laser capture microdissection and gene expression studies with microarray analysis

    Directory of Open Access Journals (Sweden)

    Ingram Jane A

    2010-01-01

    Full Text Available Abstract Background Senescent cells are well-recognized in the aging/degenerating human disc. Senescent cells are viable, cannot divide, remain metabolically active and accumulate within the disc over time. Molecular analysis of senescent cells in tissue offers a special challenge since there are no cell surface markers for senescence which would let one use fluorescence-activated cell sorting as a method for separating out senescent cells. Methods We employed a novel laser capture microdissection (LCM design to selectively harvest senescent and non-senescent annulus cells in paraffin-embedded tissue, and compared their gene expression with microarray analysis. LCM was used to separately harvest senescent and non-senescent cells from 11 human annulus specimens. Results Microarray analysis revealed significant differences in expression levels in senescent cells vs non-senescent cells: 292 genes were upregulated, and 321 downregulated. Genes with established relationships to senescence were found to be significantly upregulated in senescent cells vs. non-senescent cells: p38 (MPAK14, RB-Associated KRAB zinc finger, Discoidin, CUB and LCCL domain, growth arrest and DNA-damage inducible beta, p28ING5, sphingosine-1-phosphate receptor 2 and somatostatin receptor 3; cyclin-dependent kinase 8 showed significant downregulation in senescent cells. Nitric oxidase synthase 1, and heat shock 70 kDa protein 6, both of which were significantly down-regulated in senescent cells, also showed significant changes. Additional genes related to cytokines, cell proliferation, and other processes were also identified. Conclusions Our LCM-microarray analyses identified a set of genes associated with senescence which were significantly upregulated in senescent vs non-senescent cells in the human annulus. These genes include p38 MAP kinase, discoidin, inhibitor of growth family member 5, and growth arrest and DNA-damage-inducible beta. Other genes, including genes

  13. Interaction Mortality: Senescence May Have Evolved because It Increases Lifespan

    DEFF Research Database (Denmark)

    Wensink, M. J.; Wrycza, T. F.; Baudisch, A.

    2014-01-01

    Given an extrinsic challenge, an organism may die or not depending on how the threat interacts with the organism's physiological state. To date, such interaction mortality has been only a minor factor in theoretical modeling of senescence. We describe a model of interaction mortality that does not...... involve specific functions, making only modest assumptions. Our model distinguishes explicitly between the physiological state of an organism and potential extrinsic, age-independent threats. The resulting mortality may change with age, depending on whether the organism's state changes with age. We find...... that depending on the physiological constraints, any outcome, be it 'no senescence' or 'high rate of senescence', can be found in any environment; that the highest optimal rate of senescence emerges for an intermediate physiological constraint, i.e. intermediate strength of trade-off; and that the...

  14. Assessing senescence patterns in populations of large mammals

    Directory of Open Access Journals (Sweden)

    Gaillard, J.-M.

    2004-06-01

    Full Text Available Theoretical models such as those of Gompertz and Weibull are commonly used to study senescence in survival for humans and laboratory or captive animals. For wild populations of vertebrates, senescence in survival has more commonly been assessed by fitting simple linear or quadratic relationships between survival and age. By using appropriate constraints on survival parameters in Capture-Mark-Recapture (CMR models, we propose a first analysis of the suitability of the Gompertz and the two-parameter Weibull models for describing aging-related mortality in free-ranging populations of ungulates. We first show how to handle the Gompertz and the two-parameter Weibull models in the context of CMR analyses. Then we perform a comparative analysis of senescence patterns in both sexes of two ungulate species highly contrasted according to the intensity of sexual selection. Our analyses provide support to the Gompertz model for describing senescence patterns in ungulates. Evolutionary implications of our results are discussed

  15. Focal adhesion kinase is required for synovial fibroblast invasion, but not murine inflammatory arthritis

    OpenAIRE

    Shelef, Miriam A; Bennin, David A.; Yasmin, Nihad; Warner, Thomas F; Ludwig, Thomas; Beggs, Hilary E.; Huttenlocher, Anna

    2014-01-01

    Introduction Synovial fibroblasts invade cartilage and bone, leading to joint destruction in rheumatoid arthritis. However, the mechanisms that regulate synovial fibroblast invasion are not well understood. Focal adhesion kinase (FAK) has been implicated in cellular invasion in several cell types, and FAK inhibitors are in clinical trials for cancer treatment. Little is known about the role of FAK in inflammatory arthritis, but, given its expression in synovial tissue, its known role in invas...

  16. Immune targeting of fibroblast activation protein triggers recognition of multipotent bone marrow stromal cells and cachexia

    OpenAIRE

    Tran, Eric; Chinnasamy, Dhanalakshmi; Yu, Zhiya; Morgan, Richard A.; Lee, Chyi-Chia Richard; Restifo, Nicholas P; Rosenberg, Steven A.

    2013-01-01

    Fibroblast activation protein (FAP) is a candidate universal target antigen because it has been reported to be selectively expressed in nearly all solid tumors by a subset of immunosuppressive tumor stromal fibroblasts. We verified that 18/18 human tumors of various histologies contained pronounced stromal elements staining strongly for FAP, and hypothesized that targeting tumor stroma with FAP-reactive T cells would inhibit tumor growth in cancer-bearing hosts. T cells genetically engineered...

  17. Leaf senescence in alstroemeria: regulation by phytochrome gibberellins and cytokinins.

    OpenAIRE

    Kappers, I

    1998-01-01

    Leaf senescence in plants is a regulated process influenced by light as well as phytohormones. In the present study the putative role of the phytohormones cytokinins and gibberellins as mediators for the light signal on leaf senescence in alstroemeria was studied. It was found that low photon fluences of red light ensured maximal delay of chlorophyll and protein breakdown. This effect of red light could be completely counteracted by a subsequent far red irradiation, indicating phytochrome inv...

  18. Five dysfunctional telomeres predict onset of senescence in human cells

    OpenAIRE

    Kaul, Zeenia; Cesare, Anthony J.; Huschtscha, Lily I.; Neumann, Axel A.; Reddel, Roger R

    2011-01-01

    Replicative senescence is accompanied by a telomere-specific DNA damage response (DDR). We found that DDR+ telomeres occur spontaneously in early-passage normal human cells and increase in number with increasing cumulative cell divisions. DDR+ telomeres at replicative senescence retain TRF2 and RAP1 proteins, are not associated with end-to-end fusions and mostly result from strand-independent, postreplicative dysfunction. On the basis of the calculated number of DDR+ telomeres in G1-phase cel...

  19. Members of the barley NAC transcription factor gene family show differential co-regulation with senescence-associated genes during senescence of flag leaves

    DEFF Research Database (Denmark)

    Christiansen, Michael W; Gregersen, Per L.

    2014-01-01

    NAC transcription factor family during senescence of barley flag leaves was studied. Several members of the NAC transcription factor gene family were up-regulated during senescence in a microarray experiment, together with a large range of senescence-associated genes, reflecting the coordinated...

  20. Microprobe analysis of human fibroblasts

    International Nuclear Information System (INIS)

    The Melbourne Proton Microprobe has been used to study the copper content in human skin fibroblast cells derived from patients with the genetic disease Menkes Syndrome. Both normal and diseased cells have been studied to investigate any elemental differences occurring between the two cell types. This paper details the preparatory techniques necessary for individual cell analysis and presents the elemental information with a new three dimensional contour mapping technique. These maps are used to highlight elemental differences between normal and mutant fibroblasts. The work also confirms the expected copper excess found in the Menkes cell and indicates that the microprobe can be used for rapid identification of a Menkes carrier

  1. Arsenic exposure through drinking water leads to senescence and alteration of telomere length in humans: A case-control study in West Bengal, India.

    Science.gov (United States)

    Chatterjee, Debmita; Bhattacharjee, Pritha; Sau, Tanmoy J; Das, Jayanta K; Sarma, Nilendu; Bandyopadhyay, Apurba K; Roy, Sib Sankar; Giri, Ashok K

    2015-09-01

    Arsenic (As) induces pre-malignant and malignant dermatological lesions, non-dermatological health effects and cancers in humans. Senescence involves telomere length changes and acquisition of senescence-associated secretory phenotype (SASP), which promotes carcinogenesis. Though in vitro studies have shown that As induces senescence, population based studies are lacking. We investigated the arsenic-induced senescence, telomere length alteration and its contribution towards development of As-induced skin cancer. The study participants included 60 each of As-exposed individuals with skin lesion (WSL), without skin lesions (WOSL) and 60 unexposed controls. Exposure assessment of drinking water and urine was done. SA β-gal activity, ELISA, and quantification of senescence proteins, alternative lengthening of telomere (ALT) associated proteins and telomerase activity were performed. Relative telomere length (RTL) was determined by qPCR. A significantly higher number of senescent cells, over-expression of p53 and p21 were observed in the As-exposed individuals when compared to unexposed. SASP markers, MMP-1/MMP-3 were significantly higher in the WSL but not IL-6/IL-8. A significant increase of RTL was observed in the WSL group, which was telomerase-independent but exhibited an over-expression of ALT associated proteins TRF-1 and TRF-2 with higher increase in TRF-2. An increased risk for developing As-induced skin lesions was found for individuals having RTL greater than 0.827 (odds ratio, 13.75; 95% CI: 5.66-33.41; P telomere length might be useful for predicting the risk of development of As-induced skin lesions. PMID:24665044

  2. Density dependence triggers runaway selection of reduced senescence.

    Directory of Open Access Journals (Sweden)

    Robert M Seymour

    2007-12-01

    Full Text Available In the presence of exogenous mortality risks, future reproduction by an individual is worth less than present reproduction to its fitness. Senescent aging thus results inevitably from transferring net fertility into younger ages. Some long-lived organisms appear to defy theory, however, presenting negligible senescence (e.g., hydra and extended lifespans (e.g., Bristlecone Pine. Here, we investigate the possibility that the onset of vitality loss can be delayed indefinitely, even accepting the abundant evidence that reproduction is intrinsically costly to survival. For an environment with constant hazard, we establish that natural selection itself contributes to increasing density-dependent recruitment losses. We then develop a generalized model of accelerating vitality loss for analyzing fitness optima as a tradeoff between compression and spread in the age profile of net fertility. Across a realistic spectrum of senescent age profiles, density regulation of recruitment can trigger runaway selection for ever-reducing senescence. This novel prediction applies without requirement for special life-history characteristics such as indeterminate somatic growth or increasing fecundity with age. The evolution of nonsenescence from senescence is robust to the presence of exogenous adult mortality, which tends instead to increase the age-independent component of vitality loss. We simulate examples of runaway selection leading to negligible senescence and even intrinsic immortality.

  3. Human endothelial senescence can be induced by TNF-α

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    TNF-α is one of the most important proinfiammatory cytokines in mediating multiple physio-pathological functions during immunological responses. Vascular endothelial cells, when stimulated by TNF-α2 can increase the expression of multiple cytokines and cellular adhesion molecules and, in turn, actively promote the inflammatory responses by recruiting and activating of leukocytes to the inflammatory site. In addition to endothelial death induced by TNF-α2 we found for the first time that TNF-α can also induce the human endothelial cells senescence. The induced senescent endothelial cells will display SA-β-Gal staining and they were arrested in G0-G1 phase. We found that Aψm would always be up-regulated in response to TNF-α stimulation at early time but when the cells become senescent, A ψmshows a tendency to decrease. It may reflect the sthenic function of mitochondria at early time in response to TNF-αstimulation and decay when the endothelial cells were induced senescent. ROS fluctuates at early time and also decreases when the endothelial cells become senescent. Our results show that the change of mitochondrial function may be related to the senescent process.``

  4. Gene pathways that delay Caenorhabditis elegans reproductive senescence.

    Directory of Open Access Journals (Sweden)

    Meng C Wang

    2014-12-01

    Full Text Available Reproductive senescence is a hallmark of aging. The molecular mechanisms regulating reproductive senescence and its association with the aging of somatic cells remain poorly understood. From a full genome RNA interference (RNAi screen, we identified 32 Caenorhabditis elegans gene inactivations that delay reproductive senescence and extend reproductive lifespan. We found that many of these gene inactivations interact with insulin/IGF-1 and/or TGF-β endocrine signaling pathways to regulate reproductive senescence, except nhx-2 and sgk-1 that modulate sodium reabsorption. Of these 32 gene inactivations, we also found that 19 increase reproductive lifespan through their effects on oocyte activities, 8 of them coordinate oocyte and sperm functions to extend reproductive lifespan, and 5 of them can induce sperm humoral response to promote reproductive longevity. Furthermore, we examined the effects of these reproductive aging regulators on somatic aging. We found that 5 of these gene inactivations prolong organismal lifespan, and 20 of them increase healthy life expectancy of an organism without altering total life span. These studies provide a systemic view on the genetic regulation of reproductive senescence and its intersection with organism longevity. The majority of these newly identified genes are conserved, and may provide new insights into age-associated reproductive senescence during human aging.

  5. Hematopoietic Stem Cell–Derived Cancer–Associated Fibroblasts Are Novel Contributors to the Pro-Tumorigenic Microenvironment

    OpenAIRE

    McDonald, Lindsay T.; Russell, Dayvia L.; Kelly, Ryan R; Ying Xiong; Anjan Motamarry; Patel, Risha K.; Jones, Jeffrey A.; Watson, Patricia M.; Turner, David P; Watson, Dennis K.; Soloff, Adam C.; Findlay, Victoria J.; Amanda C. LaRue

    2015-01-01

    Targeting the tumor microenvironment is critical toward improving the effectiveness of cancer therapeutics. Cancer-associated fibroblasts (CAFs) are one of the most abundant cell types of the tumor microenvironment, playing an important role in tumor progression. Multiple origins for CAFs have been proposed including resident fibroblasts, adipocytes, and bone marrow. Our laboratory previously identified a novel hematopoietic stem cell (HSC) origin for CAFs; however, the functional roles of HS...

  6. Cellular senescence as the causal nexus of aging

    Directory of Open Access Journals (Sweden)

    Naina eBhatia-Dey

    2016-02-01

    Full Text Available We present cellular senescence as the ultimate driver of the aging process, as a causal nexus that bridges microscopic subcellular damage with the phenotypic, macroscopic effect of aging. It is important to understand how the various types of subcellular damage correlated with the aging process lead to the larger, visible effects of anatomical aging. While it has always been assumed that subcellular damage (cause results in macroscopic aging (effect, the bridging link between the two has been hard to define. Here, we propose that this bridge, which we term the causal nexus, is in fact cellular senescence. The subcellular damage itself does not directly cause the visible signs of aging, but rather, as the damage accumulates and reaches a critical mass, cells cease to proliferate and acquire the deleterious senescence-associated secretory phenotype (SASP which then leads to the macroscopic consequences of tissue breakdown to create the physiologically aged phenotype. Thus senescence is a precondition for anatomical aging, and this explains why aging is a gradual process that remains largely invisible during most of its progression. The subcellular damage includes shortening of telomeres, damage to mitochondria, aneuploidy and DNA double-strand breaks triggered by various genetic, epigenetic, and environmental factors. Damage pathways acting in isolation or in concert converge at the causal nexus of cellular senescence. In each species some types of damage can be more causative than in others and operate at a variable pace; for example, telomere erosion appears to be a primary cause in human cells, whereas activation of tumor suppressor genes is more causative in rodents. Such species-specific mechanisms indicate that despite different initial causes, most of aging is traced to a single convergent causal nexus: senescence. The exception is in some invertebrate species that escape senescence, and in nondividing cells such as neurons, where

  7. Molecular Mechanisms of Phosphorus Metabolism and Transport during Leaf Senescence

    Directory of Open Access Journals (Sweden)

    Kyla A. Stigter

    2015-12-01

    Full Text Available Leaf senescence, being the final developmental stage of the leaf, signifies the transition from a mature, photosynthetically active organ to the attenuation of said function and eventual death of the leaf. During senescence, essential nutrients sequestered in the leaf, such as phosphorus (P, are mobilized and transported to sink tissues, particularly expanding leaves and developing seeds. Phosphorus recycling is crucial, as it helps to ensure that previously acquired P is not lost to the environment, particularly under the naturally occurring condition where most unfertilized soils contain low levels of soluble orthophosphate (Pi, the only form of P that roots can directly assimilate from the soil. Piecing together the molecular mechanisms that underpin the highly variable efficiencies of P remobilization from senescing leaves by different plant species may be critical for devising effective strategies for improving overall crop P-use efficiency. Maximizing Pi remobilization from senescing leaves using selective breeding and/or biotechnological strategies will help to generate P-efficient crops that would minimize the use of unsustainable and polluting Pi-containing fertilizers in agriculture. This review focuses on the molecular mechanisms whereby P is remobilized from senescing leaves and transported to sink tissues, which encompasses the action of hormones, transcription factors, Pi-scavenging enzymes, and Pi transporters.

  8. Radiation-Induced Differentiation in Human Lung Fibroblast

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sa-Rah; Ahn, Ji-Yeon; Han, Young-Soo; Shim, Jie-Young; Yun, Yeon-Sook; Song, Jie-Young [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2007-10-15

    One of the most common tumors in many countries is lung cancer and patients with lung cancer may take radiotherapy. Although radiotherapy may have its own advantages, it can also induce serious problems such as acute radiation pneumonitis and pulmonary fibrosis. Pulmonary fibrosis is characterized by excessive production of {alpha}-SMA and accumulation of extracellular matrix (ECM) such as collagen and fibronectin. There has been a great amount of research about fibrosis but the exact mechanism causing the reaction is not elucidated especially in radiation-induced fibrosis. Until now it has been known that several factors such as transforming growth factor (TGF-{beta}), tumor necrosis factor (TNF), interleukin (IL)-1, IL-6, platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) are related to fibrosis. Among them TGF-{beta} with Smad signaling is known to be the main stream and other signaling molecules such as MAPK, ERK and JNK (3) also participates in the process. In addition to those above factors, it is thought that more diverse and complicate mechanisms may involve in the radiationinduced fibrosis. Therefore, to investigate the underlying mechanisms in radiation induced fibrosis, first of all, we confirmed whether radiation induces trans differentiation in human normal lung fibroblasts. Here, we suggest that not only TGF-{beta} but also radiation can induce trans differentiation in human lung fibroblast WI-38 and IMR-90.

  9. 透明质酸合酶-2在癌相关成纤维细胞促进舌癌细胞侵袭中的作用%Effects of hyaluronan synthase 2 on invasiveness of tongue cancer cells mediated by cancer-associated fibroblasts

    Institute of Scientific and Technical Information of China (English)

    张子文; 张宇; 王东苗; 江宏兵

    2014-01-01

    目的:检测透明质酸合酶2 (hyaluronan synthase 2,HAS2)在正常成纤维细胞(normal zone fibroblasts,NFs)及癌相关成纤维细胞(cancer-associated fibroblasts,CAFs)中的表达,并探讨其在CAFs介导的舌鳞癌细胞系Cal27侵袭行为中的作用.方法:分别从同一舌癌患者手术切除标本的癌组织及癌旁组织获取CAFs和NFs.免疫细胞化学、Westem blot法鉴定细胞表型.实时定量RT-PCR及Western blot检测透明质酸合酶在两种细胞中的表达.利用Transwell小室共培养模型,观察CAFs及NFs对舌癌细胞系Cal27侵袭能力的影响.利用siRNA抑制CAFs中的HAS2,并分析其对Cal27侵袭能力的影响.结果:o-SMA表达于CAFs,NFs中几乎无表达.Cal27在CAFs组中的侵袭力显著高于NFs组及空白对照组(P<0.01).实时定量RT-PCR结果显示HAS2在CAFs中的表达是NFs的7倍(P< 0.01),蛋白水平则为NFs的3倍(P<0.01);Cal27在HAS2干扰组的侵袭力显著低于CAFs组及无关序列组(P<0.01).结论:CAFs具有促进舌癌细胞侵袭能力的作用,高表达HAS2可能是其作用机制之一,抑制肿瘤微环境中CAFs的HAS2功能可能是一条新的抗肿瘤侵袭转移的途径.

  10. L-Lactate Protects Skin Fibroblasts against Aging-Associated Mitochondrial Dysfunction via Mitohormesis

    Directory of Open Access Journals (Sweden)

    Jaroslav Zelenka

    2015-01-01

    Full Text Available A moderate elevation of reactive oxygen species (ROS production and a mild inhibition of mitochondrial respiratory chain have been associated with a health promotion and a lifespan extension in several animal models of aging. Here, we tested whether this phenomenon called mitohormesis could be mediated by L-lactate. The treatment with 5 mM L-lactate significantly increased H2O2 production and slightly inhibited the respiration in cultured skin fibroblasts and in isolated mitochondria. The L-lactate exposure was associated with oxidation of intracellular glutathione, phosphorylation of 5′AMP-activated protein kinase (AMPK, and induction of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α transcription. A replicative aging of fibroblasts (L0 with a constant (LC, or intermittent 5 mM L-lactate (LI in media showed that the high-passage LI fibroblasts have higher respiration, lower H2O2 release, and lower secretion of L-lactate compared to L0 and LC. This protection against mitochondrial dysfunction in LI cells was associated with lower activity of mechanistic target of rapamycin complex 1 (mTORC1, less signs of cellular senescence, and increased autophagy compared to L0 and LC. In conclusion, we demonstrated that intermittent but not constant exposure to L-lactate triggers mitohormesis, prevents aging-associated mitochondrial dysfunction, and improves other markers of aging.

  11. iNOS signaling interacts with COX-2 pathway in colonic fibroblasts.

    Science.gov (United States)

    Zhu, Yingting; Zhu, Min; Lance, Peter

    2012-10-01

    COX-2 and iNOS are two major inflammatory mediators implicated in colorectal inflammation and cancer. Previously, the role of colorectal fibroblasts involved in regulation of COX-2 and iNOS expression was largely ignored. In addition, the combined interaction of COX-2 and iNOS signalings and their significance in the progression of colorectal inflammation and cancer within the fibroblasts have received little investigation. To address those issues, we investigated the role of colonic fibroblasts in the regulation of COX-2 and iNOS gene expression, and explored possible mechanisms of interaction between COX-2 and iNOS signalings using a colonic CCD-18Co fibroblast line and LPS, a potential stimulator of COX-2 and iNOS. Our results clearly demonstrated that LPS activated COX-2 gene expression and enhanced PGE(2) production, stimulated iNOS gene expression and promoted NO production in the fibroblasts. Interestingly, activation of COX-2 signaling by LPS was not involved in activation of iNOS signaling, while activation of iNOS signaling by LPS contributed in part to activation of COX-2 signaling. Further analysis indicated that PKC plays a major role in the activation and interaction of COX-2 and iNOS signalings induced by LPS in the fibroblasts. PMID:22683859

  12. Transcriptional Analysis of Normal Human Fibroblast Responses to Microgravity Stress

    Institute of Scientific and Technical Information of China (English)

    Yongqing Liu; Eugenia Wang

    2008-01-01

    To understand the molecular mechanism (s) of how spaceflight affects cellular signaling pathways, quiescent normal human WI-38 fibroblasts were flown on the STS-93 space shuttle mission. Subsequently, RNA samples from the space flown and ground-control cells were used to construct two cDNA libraries, which were then processed for suppression subtractive hybridization (SSH) to identify spaceflight-specific gene expression. The SSH data show that key genes related to oxidative stress, DNA repair, and fatty acid oxidation are activated by spaceflight, suggesting the induction of cellular oxidative stress. This is further substantiated by the up-regulation of neuregulin 1 and the calcium-binding protein calmodulin 2. Another obvious stress sign is that spaceflight evokes the Ras/mitogen-activated protein kinase and phosphatidylinositol-3 kinase signaling pathways, along with up-regulating several G1-phase cell cycle traverse genes. Other genes showing up regulation of expression are involved in protein synthesis and pro-apoptosis, as well as pro-survival. Interactome analysis of functionally related genes shows that c-Myc is the "hub" for those genes showing significant changes. Hence, our results suggest that microgravity travel may impact changes in gene expression mostly associated with cellular stress signaling, directing cells to either apoptotic death or premature senescence.

  13. Cell fusion induced by ERVWE1 or measles virus causes cellular senescence

    OpenAIRE

    Chuprin, Anna; Gal, Hilah; BIRON-SHENTAL, Tal; Biran, Anat; Amiel, Aliza; Rozenblatt, Shmuel; Krizhanovsky, Valery

    2013-01-01

    Cellular senescence limits proliferation of potentially detrimental cells, preventing tumorigenesis and restricting tissue damage. However, the function of senescence in nonpathological conditions is unknown. Here, Krizhanovsky and colleagues discover a new pathway to activate senescence cell fusion. The authors find that fusion-induced senescence occurs during embryonic development in the placenta. A counterpart of this process is also observed after infection by the measles virus. The resul...

  14. Human RON receptor tyrosine kinase induces complete epithelial-to-mesenchymal transition but causes cellular senescence

    International Nuclear Information System (INIS)

    The RON receptor tyrosine kinase is a member of the MET proto-oncogene family and is important for cell proliferation, differentiation, and cancer development. Here, we created a series of Madin-Darby canine kidney (MDCK) epithelial cell clones that express different levels of RON, and have investigated their biological properties. While low levels of RON correlated with little morphological change in MDCK cells, high levels of RON expression constitutively led to morphological scattering or complete and stabilized epithelial-to-mesenchymal transition (EMT). Unexpectedly, MDCK clones expressing higher levels of RON exhibited retarded proliferation and senescence, despite increased motility and invasiveness. RON was constitutively tyrosine-phosphorylated in MDCK cells expressing high levels of RON and undergoing EMT, and the MAPK signaling pathway was activated. This study reveals for the first time that RON alone is sufficient to induce complete and stabilized EMT in MDCK cells, and overexpression of RON does not cause cell transformation but rather induces cell cycle arrest and senescence, leading to impaired cell proliferation

  15. Cell Senescence in Myxoid/Round Cell Liposarcoma

    Directory of Open Access Journals (Sweden)

    Christina Kåbjörn Gustafsson

    2014-01-01

    Full Text Available Myxoid/round cell liposarcoma (MLS/RCLS is the second most common liposarcoma type and characterized by the fusion oncogenes FUS-DDIT3 or EWSR1-DDIT3. Previous analysis of cell cycle regulatory proteins revealed a prominent expression of G1-cyclins, cyclin dependent kinases, and their inhibitors but very few cells progressing through the G1/S boundary. Here, we extend the investigation to proteins involved in cell senescence in an immunohistochemistry based study of 17 MLS/RCLS cases. Large subpopulations of tumor cells expressed the RBL2 pocket protein and senescence associated heterochromatin 1γ and IL8 receptor β. We conclude that MLS/RCLS tissues contain major populations of senescent tumor cells and this may explain the slow growth rate of this tumor type.

  16. Chlorophyll loss associated with heat-induced senescence in bentgrass.

    Science.gov (United States)

    Jespersen, David; Zhang, Jing; Huang, Bingru

    2016-08-01

    Heat stress-induced leaf senescence is characterized by the loss of chlorophyll from leaf tissues. The objectives of this study were to examine genetic variations in the level of heat-induced leaf senescence in hybrids of colonial (Agrostis capillaris)×creeping bentgrass (Agrostis stolonifera) contrasting in heat tolerance, and determine whether loss of leaf chlorophyll during heat-induced leaf senescence was due to suppressed chlorophyll synthesis and/or accelerated chlorophyll degradation in the cool-season perennial grass species. Plants of two hybrid backcross genotypes ('ColxCB169' and 'ColxCB190') were exposed to heat stress (38/33°C, day/night) for 28 d in growth chambers. The analysis of turf quality, membrane stability, photochemical efficiency, and chlorophyll content demonstrated significant variations in the level of leaf senescence induced by heat stress between the two genotypes, with ColXCB169 exhibiting a lesser degree of decline in chlorophyll content, photochemical efficiency and membrane stability than ColXCB190. The assays of enzymatic activity or gene expression of several major chlorophyll-synthesizing (porphobilinogen deaminase, Mg-chelatase, protochlorophyllide-reductase) and chlorophyll-degrading enzymes (chlorophyllase, pheophytinase, and chlorophyll-degrading peroxidase) indicated heat-induced decline in leaf chlorophyll content was mainly due to accelerated chlorophyll degradation, as manifested by increased gene expression levels of chlorophyllase and pheophytinase, and the activity of pheophytinase (PPH), while chlorophyll-synthesizing genes and enzymatic activities were not differentially altered by heat stress in the two genotypes. The analysis of heat-induced leaf senescence of pph mutants of Arabidopsis further confirmed that PPH could be one enzymes that plays key roles in regulating heat-accelerated chlorophyll degradation. Further research on enzymes responsible in part for the loss of chlorophyll during heat

  17. Reprogramming suppresses premature senescence phenotypes of Werner syndrome cells and maintains chromosomal stability over long-term culture.

    Directory of Open Access Journals (Sweden)

    Akira Shimamoto

    Full Text Available Werner syndrome (WS is a premature aging disorder characterized by chromosomal instability and cancer predisposition. Mutations in WRN are responsible for the disease and cause telomere dysfunction, resulting in accelerated aging. Recent studies have revealed that cells from WS patients can be successfully reprogrammed into induced pluripotent stem cells (iPSCs. In the present study, we describe the effects of long-term culture on WS iPSCs, which acquired and maintained infinite proliferative potential for self-renewal over 2 years. After long-term cultures, WS iPSCs exhibited stable undifferentiated states and differentiation capacity, and premature upregulation of senescence-associated genes in WS cells was completely suppressed in WS iPSCs despite WRN deficiency. WS iPSCs also showed recapitulation of the phenotypes during differentiation. Furthermore, karyotype analysis indicated that WS iPSCs were stable, and half of the descendant clones had chromosomal profiles that were similar to those of parental cells. These unexpected properties might be achieved by induced expression of endogenous telomerase gene during reprogramming, which trigger telomerase reactivation leading to suppression of both replicative senescence and telomere dysfunction in WS cells. These findings demonstrated that reprogramming suppressed premature senescence phenotypes in WS cells and WS iPSCs could lead to chromosomal stability over the long term. WS iPSCs will provide opportunities to identify affected lineages in WS and to develop a new strategy for the treatment of WS.

  18. Platinum(II) phenanthroimidazole G-quadruplex ligand induces selective telomere shortening in A549 cancer cells.

    Science.gov (United States)

    Mancini, Johanna; Rousseau, Philippe; Castor, Katherine J; Sleiman, Hanadi F; Autexier, Chantal

    2016-02-01

    Telomere maintenance, achieved by the binding of protective shelterin capping proteins to telomeres and by either telomerase or a recombination-based alternative lengthening of telomere (ALT) mechanism, is critical for cell proliferation and survival. Extensive telomere shortening or loss of telomere integrity activates DNA damage checkpoints, leading to cell senescence or death. Although telomerase upregulation is an attractive target for anti-cancer therapy, the lag associated with telomere shortening and the potential activation of ALT pose a challenge. An alternative approach is to modify telomere interactions with binding proteins (telomere uncapping). G-quadruplex ligands stabilize structures generated from single-stranded G-rich 3'-telomere end (G-quadruplex) folding, which in principle, cannot be elongated by telomerase, thus leading to telomere shortening. Ligands can also mediate rapid anti-proliferative effects by telomere uncapping. We previously reported that the G-quadruplex ligand, phenylphenanthroimidazole ethylenediamine platinum(II) (PIP), inhibits telomerase activity in vitro[47]. In the current study, a long-term seeding assay showed that PIP significantly inhibited the seeding capacity of A549 lung cancer cells and to a lesser extent primary MRC5 fibroblast cells. Importantly, treatment with PIP caused a significant dose- and time-dependent decrease in average telomere length of A549 but not MRC5 cells. Moreover, cell cycle analysis revealed a significant increase in G1 arrest upon treatment of A549 cells, but not MRC5 cells. Both apoptosis and cellular senescence may contribute to the anti-proliferative effects of PIP. Our studies validate the development of novel and specific therapeutic ligands targeting telomeric G-quadruplex structures in cancer cells. PMID:26724375

  19. Radiation-induced gene expression in human subcutaneous fibroblasts is predictive of radiation-induced fibrosis

    DEFF Research Database (Denmark)

    Rødningen, Olaug Kristin; Børresen-Dale, Anne-Lise; Alsner, Jan;

    2008-01-01

    BACKGROUND AND PURPOSE: Breast cancer patients show a large variation in normal tissue reactions after ionizing radiation (IR) therapy. One of the most common long-term adverse effects of ionizing radiotherapy is radiation-induced fibrosis (RIF), and several attempts have been made over the last...... years to develop predictive assays for RIF. Our aim was to identify basal and radiation-induced transcriptional profiles in fibroblasts from breast cancer patients that might be related to the individual risk of RIF in these patients. MATERIALS AND METHODS: Fibroblast cell lines from 31 individuals with......-treated fibroblasts. Transcriptional differences in basal and radiation-induced gene expression profiles were investigated using 15K cDNA microarrays, and results analyzed by both SAM and PAM. RESULTS: Sixty differentially expressed genes were identified by applying SAM on 10 patients with the highest risk of RIF and...

  20. Abnormal phenotype of human cultured fibroblasts from superficial radiation-induced fibrosis (RIF)

    International Nuclear Information System (INIS)

    Pathophysiological aspects of human RIF have not been well characterized and our present knowledge is mostly established on extrapolated data from experimental in vivo studies or in vitro cell irradiation. We developed human cell cultures from superficial RIF samples, in order to analyze directly the long term process following therapeutic irradiation. Our study showed that in human RIF, characterized by an heterogeneous extra-cellular matrix deposition, atrophic vascularization, myo-fibroblast like cells and inflammatory cells, the surviving cells in culture exhibited a dramatic reduced proliferation and a low metabolism, characteristic signs of a senescence process. These results might explain the delayed radiation-induced necrosis as an ultimate evolution of RIF. (authors)

  1. Repairing DNA damage by XRCC6/KU70 reverses TLR4-deficiency-worsened HCC development via restoring senescence and autophagic flux

    OpenAIRE

    Wang, Ziyan; Lin, Heng; Hua, Fang; Hu, Zhuo-Wei

    2013-01-01

    Hepatocellular carcinoma (HCC) is among the most lethal and prevalent cancers in the human population. The initiation and progression of HCC is closely associated with chronic liver inflammation. Recent research indicates that nonhomologous end joining (NHEJ), one of the DNA repair mechanisms, autophagy and senescence are all involved in the pathogenesis of HCC induced by carcinogens or oxidative stress. DNA repair proteins including XRCC6/KU70 and XRCC5/KU80 are the critical NHEJ factors tha...

  2. Role of polyamines and ethylene as modulators of plant senescence

    Indian Academy of Sciences (India)

    S Pandey; S A Ranade; P K Nagar; Nikhil Kumar

    2000-09-01

    Under optimal conditions of growth, senescence, a terminal phase of development, sets in after a certain physiological age. It is a dynamic and closely regulated developmental process which involves an array of changes at both physiological and biochemical levels including gene expression. A large number of biotic and abiotic factors accelerate the process. Convincing evidence suggests the involvement of polyamines (PAs) and ethylene in this process. Although the biosynthetic pathways of both PAs and ethylene are interrelated, S-adenosylmethionine (SAM) being a common precursor, their physiological functions are distinct and at times antagonistic, particularly during leaf and flower senescence and also during fruit ripening. This provides an effective means for regulation of their biosynthesis and also to understand the mechanism by which the balance between the two can be established for manipulating the senescence process. The present article deals with current advances in the knowledge of the interrelationship between ethylene and PAs during senescence which may open up new vistas of investigation for the future.

  3. TP53inp1 Gene Is Implicated in Early Radiation Response in Human Fibroblast Cells

    Directory of Open Access Journals (Sweden)

    Nikolett Sándor

    2015-10-01

    Full Text Available Tumor protein 53-induced nuclear protein-1 (TP53inp1 is expressed by activation via p53 and p73. The purpose of our study was to investigate the role of TP53inp1 in response of fibroblasts to ionizing radiation. γ-Ray radiation dose-dependently induces the expression of TP53inp1 in human immortalized fibroblast (F11hT cells. Stable silencing of TP53inp1 was done via lentiviral transfection of shRNA in F11hT cells. After irradiation the clonogenic survival of TP53inp1 knockdown (F11hT-shTP cells was compared to cells transfected with non-targeting (NT shRNA. Radiation-induced senescence was measured by SA-β-Gal staining and autophagy was detected by Acridine Orange dye and microtubule-associated protein-1 light chain 3 (LC3B immunostaining. The expression of TP53inp1, GDF-15, and CDKN1A and alterations in radiation induced mitochondrial DNA deletions were evaluated by qPCR. TP53inp1 was required for radiation (IR induced maximal elevation of CDKN1A and GDF-15 expressions. Mitochondrial DNA deletions were increased and autophagy was deregulated following irradiation in the absence of TP53inp1. Finally, we showed that silencing of TP53inp1 enhances the radiation sensitivity of fibroblast cells. These data suggest functional roles for TP53inp1 in radiation-induced autophagy and survival. Taken together, we suppose that silencing of TP53inp1 leads radiation induced autophagy impairment and induces accumulation of damaged mitochondria in primary human fibroblasts.

  4. RNAi-mediated knocking- down of rlpk2 gene retarded soybean leaf senescence

    Institute of Scientific and Technical Information of China (English)

    LI Xiaoping; MA Yuanyuan; LI Pengli; ZHANG Liwen; WANG Yong; ZHANG Ren; WANG Ningning

    2005-01-01

    Leaf senescence that occurs in the last stage of leaf development is a genetically programmed process. It is very significant to elucidate the molecular mechanisms that control the initiation and progression of leaf senescence and the way the senescence signal is transduced. In a previous study on artificially induced soybean leaf senescence, we cloned a novel gene designated rlpk2 (Genbank Accession No. AY687391) that encodes a leucine-rich repeat (LRR) receptor like protein kinase. The expression level of rlpk2 gene was shown to be strongly up-regulated during both the natural leaf senescence process in this report and the artificially induced primary-leaf-senescence process in our previous work. The RNA interference (RNAi)-mediated knocking-down of rlpk2 dramatically retarded both the natural and nutrient deficiency-induced leaf senescence in transgenic soybean. The transgenic leaves showed more cell-aggregated surface structure and higher content of chlorophyll.

  5. Random mtDNA mutations modulate proliferation capacity in mouse embryonic fibroblasts

    International Nuclear Information System (INIS)

    Highlights: → Increased mtDNA mutations in MEFs lead to high level of spontaneous immortalization. → This process is independent of endogenous ROS production. → Aerobic glycolysis significantly contributes to spontaneous immortalization of MEFs. -- Abstract: An increase in mtDNA mutation load leads to a loss of critical cells in different tissues thereby contributing to the physiological process of organismal ageing. Additionally, the accumulation of senescent cells that display changes in metabolic function might act in an active way to further disrupt the normal tissue function. We believe that this could be the important link missing in our understanding of the molecular mechanisms of premature ageing in the mtDNA mutator mice. We tested proliferation capacity of mtDNA mutator cells in vitro. When cultured in physiological levels of oxygen (3%) their proliferation capacity is somewhat lower than wild-type cells. Surprisingly, in conditions of increased oxidative stress (20% O2) mtDNA mutator mouse embryonic fibroblasts exhibit continuous proliferation due to spontaneous immortalization, whereas the same conditions promote senescence in wild-type cells. We believe that an increase in aerobic glycolysis observed in mtDNA mutator mice is a major mechanism behind this process. We propose that glycolysis promotes proliferation and allows a fast turnover of metabolites, but also leads to energy crisis due to lower ATP production rate. This could lead to compromised replication and/or repair and therefore, in rare cases, might lead to mutations in tumor suppressor genes and spontaneous immortalization.

  6. Random mtDNA mutations modulate proliferation capacity in mouse embryonic fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Kukat, Alexandra [Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institute, S-17171 Stockholm (Sweden); Cologne Excellence Cluster on Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Cologne University Clinic, D-50674 Cologne (Germany); Edgar, Daniel [Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institute, S-17171 Stockholm (Sweden); Bratic, Ivana [Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institute, S-17171 Stockholm (Sweden); Cologne Excellence Cluster on Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Cologne University Clinic, D-50674 Cologne (Germany); Maiti, Priyanka [Cologne Excellence Cluster on Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Cologne University Clinic, D-50674 Cologne (Germany); Trifunovic, Aleksandra, E-mail: aleksandra.trifunovic@ki.se [Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institute, S-17171 Stockholm (Sweden); Cologne Excellence Cluster on Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Cologne University Clinic, D-50674 Cologne (Germany)

    2011-06-10

    Highlights: {yields} Increased mtDNA mutations in MEFs lead to high level of spontaneous immortalization. {yields} This process is independent of endogenous ROS production. {yields} Aerobic glycolysis significantly contributes to spontaneous immortalization of MEFs. -- Abstract: An increase in mtDNA mutation load leads to a loss of critical cells in different tissues thereby contributing to the physiological process of organismal ageing. Additionally, the accumulation of senescent cells that display changes in metabolic function might act in an active way to further disrupt the normal tissue function. We believe that this could be the important link missing in our understanding of the molecular mechanisms of premature ageing in the mtDNA mutator mice. We tested proliferation capacity of mtDNA mutator cells in vitro. When cultured in physiological levels of oxygen (3%) their proliferation capacity is somewhat lower than wild-type cells. Surprisingly, in conditions of increased oxidative stress (20% O{sub 2}) mtDNA mutator mouse embryonic fibroblasts exhibit continuous proliferation due to spontaneous immortalization, whereas the same conditions promote senescence in wild-type cells. We believe that an increase in aerobic glycolysis observed in mtDNA mutator mice is a major mechanism behind this process. We propose that glycolysis promotes proliferation and allows a fast turnover of metabolites, but also leads to energy crisis due to lower ATP production rate. This could lead to compromised replication and/or repair and therefore, in rare cases, might lead to mutations in tumor suppressor genes and spontaneous immortalization.

  7. So You Can Teach Old Fibroblasts New Tricks.

    Science.gov (United States)

    Virós, Amaya; Girotti, Maria Romina; Marais, Richard

    2016-06-01

    New data show that as dermal fibroblasts grow old, they increase their secretion of the WNT antagonist sFRP2 to drive melanoma cell metastasis. sFRP2 suppresses β-catenin and MITF signaling in melanoma cells, downregulating the redox regulator APE1, making melanoma cells more sensitive to oxidative stress and driving resistance to BRAF inhibitors. Thus, the aging microenvironment in elderly patient skin activates a signaling pathway that drives more aggressive melanoma cell behavior. Cancer Discov; 6(6); 581-3. ©2016 AACR. PMID:27261482

  8. Mitochondrial pAL2-1 plasmid homologs are senescence factors in Podospora anserina independent of intrinsic senescence

    NARCIS (Netherlands)

    van Diepeningen, Anne D; Debets, Alfons J M; Slakhorst, S Marijke; Hoekstra, Rolf F

    2008-01-01

    Since the first description of a linear mitochondrial plasmid in Podospora anserina, pAL2-1, and homologous plasmids have gone from being considered beneficial longevity plasmids, via neutral genetic elements, toward mutator plasmids causing senescence. The plasmid has an invertron structure, with t

  9. Dehydroleucodine inhibits tumor growth in a preclinical melanoma model by inducing cell cycle arrest, senescence and apoptosis.

    Science.gov (United States)

    Costantino, Valeria V; Lobos-Gonzalez, Lorena; Ibañez, Jorge; Fernandez, Dario; Cuello-Carrión, F Darío; Valenzuela, Manuel A; Barbieri, Manuel A; Semino, Silvana N; Jahn, Graciela A; Quest, Andrew F G; Lopez, Luis A

    2016-03-01

    Malignant melanoma represents the fastest growing public health risk of all cancer types worldwide. Several strategies and anti-cancer drugs have been used in an effort to improve treatments, but the development of resistance to anti-neoplastic drugs remains the major cause of chemotherapy failure in melanomas. Previously, we showed that the sesquiterpene lactone, dehydroleucodine (DhL), promotes the accumulation of DNA damage markers, such as H2AX and 53BP1, in human tumor cells. Also DhL was shown to trigger either cell senescence or apoptosis in a concentration-dependent manner in HeLa and MCF7 cells. Here, we evaluated the effects of DhL on B16F0 mouse melanoma cells in vitro and in a pre-clinical melanoma model. DhL inhibited the proliferation of B16F0 cells by inducing senescence or apoptosis in a concentration-dependent manner. Also, DhL reduced the expression of the cell cycle proteins cyclin D1 and B1 and the inhibitor of apoptosis protein, survivin. In melanomas generated by subcutaneous injection of B16F0 cells into C57/BL6 mice, the treatment with 20 mg DhL /Kg/day in preventive, simultaneous and therapeutic protocols reduced tumor volumes by 70%, 60% and 50%, respectively. DhL treatments reduced the number of proliferating, while increasing the number of senescent and apoptotic tumor cells. To estimate the long-term effects of DhL, a mathematical model was applied to fit experimental data. Extrapolation beyond experimental time points revealed that DhL administration following preventive and therapeutic protocols is predicted to be more effective than simultaneous treatments with DhL in restricting tumor growth. PMID:26718258

  10. From Accumulation to Degradation: Reprogramming Polyamine Metabolism Facilitates Dark-Induced Senescence in Barley Leaf Cells

    Science.gov (United States)

    Sobieszczuk-Nowicka, Ewa; Kubala, Szymon; Zmienko, Agnieszka; Małecka, Arleta; Legocka, Jolanta

    2016-01-01

    The aim of this study was to analyze whether polyamine (PA) metabolism is involved in dark-induced Hordeum vulgare L. ‘Nagrad’ leaf senescence. In the cell, the titer of PAs is relatively constant and is carefully controlled. Senescence-dependent increases in the titer of the free PAs putrescine, spermidine, and spermine occurred when the process was induced, accompanied by the formation of putrescine conjugates. The addition of the anti-senescing agent cytokinin, which delays senescence, to dark-incubated leaves slowed the senescence-dependent PA accumulation. A feature of the senescence process was initial accumulation of PAs at the beginning of the process and their subsequent decrease during the later stages. Indeed, the process was accompanied by both enhanced expression of PA biosynthesis and catabolism genes and an increase in the activity of enzymes involved in the two metabolic pathways. To confirm whether the capacity of the plant to control senescence might be linked to PA, chlorophyll fluorescence parameters, and leaf nitrogen status in senescing barley leaves were measured after PA catabolism inhibition and exogenously applied γ-aminobutyric acid (GABA). The results obtained by blocking putrescine oxidation showed that the senescence process was accelerated. However, when the inhibitor was applied together with GABA, senescence continued without disruption. On the other hand, inhibition of spermidine and spermine oxidation delayed the process. It could be concluded that in dark-induced leaf senescence, the initial accumulation of PAs leads to facilitating their catabolism. Putrescine supports senescence through GABA production and spermidine/spermine supports senescence-dependent degradation processes, is verified by H2O2 generation. PMID:26779231

  11. MicroRNA-191 triggers keratinocytes senescence by SATB1 and CDK6 downregulation

    International Nuclear Information System (INIS)

    Highlights: ► miR-191 expression is upregulated in senescencent human epidermal keratinocytes. ► miR-191 overexpression is sufficient per se to induce senescence in keratinocytes. ► SATB1 and CDK6 are downregulated in senescence and are direct miR-191 targets. ► SATB1 and CDK6 silencing by siRNA triggers senescence in HEKn cells. -- Abstract: Keratinocyte replicative senescence has an important role in time-dependent changes of the epidermis, a tissue with high turnover. Senescence encompasses growth arrest during which cells remain metabolically active but acquire a typical enlarged, vacuolar and flattened morphology. It is also accompanied by the expression of endogenous senescence-associated-β-galactosidase and specific gene expression profiles. MicroRNAs levels have been shown to be modulated during keratinocytes senescence, playing key roles in inhibiting proliferation and in the acquisition of senescent markers. Here, we identify miR-191 as an anti-proliferative and replicative senescence-associated miRNA in primary human keratinocytes. Its overexpression is sufficient per se to induce senescence, as evaluated by induction of several senescence-associated markers. We show that SATB1 and CDK6 3′UTRs are two miR-191 direct targets involved in this pathway. Cdk6 and Satb1 protein levels decrease during keratinocytes replicative senescence and their silencing by siRNA is able to induce a G1 block in cell cycle, accompanied by an increase in senescence-associated markers.

  12. Stressed SIRT7: facing a crossroad of senescence and immortality.

    Science.gov (United States)

    Liu, Jun-Ping; Chen, Ruping

    2015-06-01

    SIRT7 with coenzyme NAD catalyzes protein de-acetylation. In stress response, SIRT7 regulates protein folding in mitochondria with unknown mechanisms. Decreases in SIRT7 entrain hematopoietic stem cell senescence, but increasing SIRT7 causes elevation of hematopoietic stem cell regenerative function. We discuss the recent findings on SIRT7 and its binding proteins, NRF1 and GABPβ1, in decision making between the choices of inducing cell aging and immortality. PMID:25970806

  13. Mediterranean diet reduces senescence-associated stress in endothelial cells

    OpenAIRE

    Marin, Carmen; Delgado-Lista, Javier; Ramirez, Rafael; Carracedo, Julia; Caballero, Javier; Perez-Martinez, Pablo; Gutierrez-Mariscal, Francisco Miguel; Garcia-Rios, Antonio; Delgado-Casado, Nieves; Cruz-Teno, Cristina; Yubero-Serrano, Elena Maria; Tinahones, Francisco; Malagon, Maria del Mar; Perez-Jimenez, Francisco; Lopez-Miranda, Jose

    2011-01-01

    This paper aims to study the effects of the oxidative stress induced by quality and quantity of dietary fat on cellular senescence. Twenty elderly subjects consumed three diets, each for 4 weeks: a saturated fatty acid diet (SFA), a low-fat and high-carbohydrate diet (CHO-ALA), and a Mediterranean diet (MedDiet) enriched in monounsaturated fatty acid following a randomized crossover design. For each diet, we investigated intracellular reactive oxidative species (ROS), cellular apoptosis and t...

  14. Cytokines shape chemotherapy-induced and 'bystander' senescence

    Czech Academy of Sciences Publication Activity Database

    Hodný, Zdeněk; Hubáčková, Soňa; Bartek, Jiří

    2010-01-01

    Roč. 2, č. 2 (2010), s. 375-376. ISSN 1945-4589 R&D Projects: GA ČR GA204/08/1418; GA ČR GA301/08/0353 Institutional research plan: CEZ:AV0Z50520514 Keywords : bystander cellular senescence * cytokines * PML Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.964, year: 2010

  15. Degranulating mast cells in fibrotic regions of human tumors and evidence that mast cell heparin interferes with the growth of tumor cells through a mechanism involving fibroblasts

    International Nuclear Information System (INIS)

    The purpose of this study was to test the hypothesis that mast cells that are present in fibrotic regions of cancer can suppress the growth of tumor cells through an indirect mechanism involving peri-tumoral fibroblasts. We first immunostained a wide variety of human cancers for the presence of degranulated mast cells. In a subsequent series of controlled in vitro experiments, we then co-cultured UACC-812 human breast cancer cells with normal fibroblasts in the presence or absence of different combinations and doses of mast cell tryptase, mast cell heparin, a lysate of the human mast cell line HMC-1, and fibroblast growth factor-7 (FGF-7), a powerful, heparin-binding growth factor for breast epithelial cells. Degranulating mast cells were localized predominantly in the fibrous tissue of every case of breast cancer, head and neck cancer, lung cancer, ovarian cancer, non-Hodgkin's lymphoma, and Hodgkin's disease that we examined. Mast cell tryptase and HMC-1 lysate had no significant effect on the clonogenic growth of cancer cells co-cultured with fibroblasts. By contrast, mast cell heparin at multiple doses significantly reduced the size and number of colonies of tumor cells co-cultured with fibroblasts, especially in the presence of FGF-7. Neither heparin nor FGF-7, individually or in combination, produced any significant effect on the clonogenic growth of breast cancer cells cultured without fibroblasts. Degranulating mast cells are restricted to peri-tumoral fibrous tissue, and mast cell heparin is a powerful inhibitor of clonogenic growth of tumor cells co-cultured with fibroblasts. These results may help to explain the well-known ability of heparin to inhibit the growth of primary and metastatic tumors

  16. Identification and function analyses of senescence-associated WRKYs in wheat.

    Science.gov (United States)

    Zhang, Haoshan; Zhao, Mingming; Song, Qiuhang; Zhao, Lifeng; Wang, Geng; Zhou, Chunjiang

    2016-06-10

    Leaf senescence is a positive, highly regulated, complex process, and transcription factors play important roles in the regulation of this process. We identified and characterized 116 WRKYs from the wheat genome database. Thirteen TaWRKYs were confirmed as senescence-associated genes. We focused on TaWRKY7, which is up-regulated in the natural leaf senescence process. TaWRKY7 is expressed in different tissues of wheat and is localized in the nucleus. It shows transcriptional activation activity in yeast cells. The ectopic over-expression of TaWRKY7 in Arabidopsis (Arabidopsis thaliana) significantly promoted early leaf senescence under darkness treatment and prevented leaf moisture losses. TaWRKY7 played important roles in the senescence process and was involved in abiotic stress responses. Our transcriptomic and genetic studies on WRKYs suggest that WRKY transcription factors are a type of vital regulator in leaf senescence in wheat (Triticum aestivum L.). PMID:27166153

  17. Senescence-accelerated mouse (SAM): a biogerontological resource in aging research.

    Science.gov (United States)

    Takeda, T

    1999-01-01

    The senescence-accelerated mouse (SAM), consisting of 14 senescence-prone inbred strains (SAMP) and 4 senescence-resistant inbred strains (SAMR) has been under development since 1970 through the selective inbreeding of AKR/J strain mice donated by the Jackson laboratory in 1968, based on the data of the grading score of senescence, life span, and pathologic phenotypes. The characteristic feature of aging common to all SAMP and SAMR mice is accelerated senescence and normal aging, respectively. Furthermore, SAMP and SAMR strains manifest various pathobiological phenotypes which include such neurobiological phenotypes as deficits in learning and memory, emotional disorders, abnormal circadian rhythms, brain atrophy, hearing impairment, etc., and are often characteristic enough to differentiate the strains. Various efforts are currently being made using the SAM model to clarify the underlying mechanisms in accelerated senescence as well as the etiopathogenic mechanisms in age-associated pathobiologies. Genetic background and significance of SAM development are discussed. PMID:10537019

  18. Flag leaf senescence in high grain protein wheat genotypes

    International Nuclear Information System (INIS)

    Bread wheat genotypes with higher grain protein (15 to 17%) were compared with the normal grain protein (13 to 14%), high yielding cultivar Kalyan Sona for grain yield, rate of flag leaf senescence and nitrogen loss from the flag leaf during the grain filling period. High grain protein genotypes showed higher rates of flag leaf senescence and nitrogen loss. Although the potential grain number per square metre was not significantly different, a lower grain yield of high grain protein genotypes was due to poor realization of the potential grain number. The rate of flag leaf senescence and the rate of nitrogen loss from the flag leaf were positively correlated with each other and with grain protein percentage. They showed a significant negative correlation with grain yield. It is hypothesized that the increased nitrogen demand of developing seeds with genetic potential for higher grain protein induces early mobilization and breakdown of foliage proteins, thereby reducing the photosynthetic capacity. Reduced assimilate supply, in turn, causes lower realization of the potential grain number, which ultimately contributes to a lower yield. (author)

  19. Human endothelial senescence induced by IL-1α in vitro

    Institute of Scientific and Technical Information of China (English)

    YAO Aiyu; ZHOU Jianjun; LIU Yabing; FENG Meifu; ZHOU Rouli

    2004-01-01

    Interleukin 1(IL-1) is an important proinflammatory cytokine that causes pleiotropic effects. Vascular endothelial cells stimulated by IL-1α can lead to the inflammatory response. Reactive oxygen species (ROS) are also generated at the site of inflammation and serve as an important factor against foreign invader. Here we report that long-term stimulation of human vein endothelial cells with IL-1α can accelerate their senescence associated with β-galactosidase activity. The flow cytometric analyses showed that most of the induced cells entered G0-G1 phase. DNA damage was more severe in senescent cells by comet assay. The induced cells by IL-1α had higher levels of ROS and malonyldialdehyde (MDA), lower activity of antioxidant enzymes and lower capacity of total antioxidant systems than control, which led to cell damage and cell degeneration, that is to say, which contributed to cellular senescence. Our results gave a direct proof to a new hypothesis-"the inflammation hypothesis of aging" on cellular level, and also provided a basis for the study on anti-aging and aging-related diseases.

  20. Il-6 signaling between ductal carcinoma in situ cells and carcinoma-associated fibroblasts mediates tumor cell growth and migration

    OpenAIRE

    Osuala, Kingsley O.; Sameni, Mansoureh; Shah, Seema; Aggarwal, Neha; Simonait, Michelle L.; Franco, Omar E.; Hong, Yan; Hayward, Simon W.; Behbod, Fariba; Mattingly, Raymond R.; Sloane, Bonnie F.

    2015-01-01

    Background Ductal carcinoma in situ (DCIS) is a non-obligate precursor lesion of invasive breast cancer in which approximately half the patients will progress to invasive cancer. Gaining a better understanding of DCIS progression may reduce overtreatment of patients. Expression of the pro-inflammatory cytokine interleukin-6 increases with pathological stage and grade, and is associated with poorer prognosis in breast cancer patients. Carcinoma associated fibroblasts (CAFs), which are present ...

  1. Carbon/Nitrogen Imbalance Associated with Drought-Induced Leaf Senescence in Sorghum bicolor

    OpenAIRE

    Daoqian Chen; Shiwen Wang; Binglin Xiong; Beibei Cao; Xiping Deng

    2015-01-01

    Drought stress triggers mature leaf senescence, which supports plant survival and remobilization of nutrients; yet leaf senescence also critically decreases post-drought crop yield. Drought generally results in carbon/nitrogen imbalance, which is reflected in the increased carbon:nitrogen (C:N) ratio in mature leaves, and which has been shown to be involved in inducing leaf senescence under normal growth conditions. Yet the involvement of the carbon/nitrogen balance in regulation of drought-i...

  2. Delayed leaf senescence induces extreme drought tolerance in a flowering plant

    OpenAIRE

    Rivero, Rosa M.; Kojima, Mikiko; Gepstein, Amira; Sakakibara, Hitoshi; Mittler, Ron; Gepstein, Shimon; Blumwald, Eduardo

    2007-01-01

    Drought, the most prominent threat to agricultural production worldwide, accelerates leaf senescence, leading to a decrease in canopy size, loss in photosynthesis and reduced yields. On the basis of the assumption that senescence is a type of cell death program that could be inappropriately activated during drought, we hypothesized that it may be possible to enhance drought tolerance by delaying drought-induced leaf senescence. We generated transgenic plants expressing an isopentenyltransfera...

  3. Oxidative Stress Induces Endothelial Cell Senescence via Downregulation of Sirt6

    OpenAIRE

    Rong Liu; Hua Liu; Yonju Ha; Tilton, Ronald G.; Wenbo Zhang

    2014-01-01

    Accumulating evidence has shown that diabetes accelerates aging and endothelial cell senescence is involved in the pathogenesis of diabetic vascular complications, including diabetic retinopathy. Oxidative stress is recognized as a key factor in the induction of endothelial senescence and diabetic retinopathy. However, specific mechanisms involved in oxidative stress-induced endothelial senescence have not been elucidated. We hypothesized that Sirt6, which is a nuclear, chromatin-bound protei...

  4. Adaptation to altitude affects the senescence response to chilling in the perennial plant Arabis alpina

    OpenAIRE

    Wingler, Astrid; Juvany, Marta; Cuthbert, Caroline; Munné-Bosch, Sergi

    2014-01-01

    In annual plants with determinate growth, sugar accumulation signals high carbon availability once growth has ceased, resulting in senescence-dependent nutrient recycling to the seeds. However, this senescence-inducing effect of sugars is abolished at cold temperature, where sugar accumulation is important for protection. Here, natural variation was exploited to analyse the effect of chilling on interactions between leaf senescence, sugars, and phytohormones in Arabis alpina, a perennial plan...

  5. Plants do not count… or do they? New perspectives on the universality of senescence

    OpenAIRE

    Salguero-Gómez, Roberto; Shefferson, Richard P.; Hutchings, Michael J.

    2013-01-01

    1. Senescence, the physiological decline that results in decreasing survival and/or reproduction with age, remains one of the most perplexing topics in biology. Most theories explaining the evolution of senescence (i.e. antagonistic pleiotropy, accumulation of mutations, disposable soma) were developed decades ago. Even though these theories have implicitly focused on unitary animals, they have also been used as the foundation from which the universality of senescence across the tree of life ...

  6. Senescence in the wild: Insights from a long-term study on Seychelles warblers.

    Science.gov (United States)

    Hammers, Martijn; Kingma, Sjouke A; Bebbington, Kat; van de Crommenacker, Janske; Spurgin, Lewis G; Richardson, David S; Burke, Terry; Dugdale, Hannah L; Komdeur, Jan

    2015-11-01

    Senescence--the progressive age-dependent decline in performance--occurs in most organisms. There is considerable variation in the onset and rate of senescence between and within species. Yet the causes of this variation are still poorly understood, despite being central to understanding the evolution of senescence. Long-term longitudinal studies on wild animals are extremely well-suited to studying the impact of environmental and individual characteristics (and the interaction between the two) on senescence, and can help us to understand the mechanisms that shape the evolution of senescence. In this review, we summarize and discuss the insights gained from our comprehensive long-term individual-based study of the Seychelles warbler (Acrocephalus sechellensis). This species provides an excellent model system in which to investigate the evolution of senescence in the wild. We found that Seychelles warblers show senescent declines in survival and reproduction, and discuss how individual characteristics (body condition, body size) and environmental effects (low- versus high-quality environments) may affect the onset and rate of senescence. Further, we highlight the evidence for trade-offs between early-life investment and senescence. We describe how key cellular and physiological processes (oxidative stress and telomere shortening) underpinning senescence are affected by individual and environmental characteristics in the Seychelles warbler (e.g. food availability, reproductive investment, disease) and we discuss how such physiological variation may mediate the relationship between environmental characteristics and senescence. Based on our work using Seychelles warblers as a model system, we show how insights from long-term studies of wild animals may help unravel the causes of the remarkable variation in senescence observed in natural systems, and highlight areas for promising future research. PMID:26344178

  7. Intermittent Stem Cell Cycling Balances Self-Renewal and Senescence of the C. elegans Germ Line

    OpenAIRE

    Cinquin, A.; Chiang, M.; Paz, A.; Hallman, S; Yuan, O; Vysniauskaite, I; Fowlkes, CC; Cinquin, O.

    2016-01-01

    Self-renewing organs often experience a decline in function in the course of aging. It is unclear whether chronological age or external factors control this decline, or whether it is driven by stem cell self-renewal-for example, because cycling cells exhaust their replicative capacity and become senescent. Here we assay the relationship between stem cell cycling and senescence in the Caenorhabditis elegans reproductive system, defining this senescence as the progressive decline in "reproducti...

  8. Genome-Wide Transcriptional Reorganization Associated with Senescence-to-Immortality Switch during Human Hepatocellular Carcinogenesis

    OpenAIRE

    Yildiz, Gokhan; Arslan-Ergul, Ayca; Bagislar, Sevgi; Konu, Ozlen; Yuzugullu, Haluk; Gursoy-Yuzugullu, Ozge; Ozturk, Nuri; Ozen, Cigdem; Ozdag, Hilal; Erdal, Esra; Karademir, Sedat; Sagol, Ozgul; Mizrak, Dilsa; BOZKAYA, Hakan; Ilk, Hakki Gokhan

    2013-01-01

    Senescence is a permanent proliferation arrest in response to cell stress such as DNA damage. It contributes strongly to tissue aging and serves as a major barrier against tumor development. Most tumor cells are believed to bypass the senescence barrier (become “immortal”) by inactivating growth control genes such as TP53 and CDKN2A. They also reactivate telomerase reverse transcriptase. Senescence-to-immortality transition is accompanied by major phenotypic and biochemical changes mediated b...

  9. A Screen Identifies the Oncogenic Micro-RNA miR-378a-5p as a Negative Regulator of Oncogene-Induced Senescence

    DEFF Research Database (Denmark)

    Kooistra, Susanne Marije; Rudkjær, Lise Christine; Lees, Michael James; Steinhauer, Cornelia; Johansen, Jens Vilstrup; Helin, Kristian

    2014-01-01

    Oncogene-induced senescence (OIS) can occur in response to hyperactive oncogenic signals and is believed to be a fail-safe mechanism protecting against tumorigenesis. To identify new factors involved in OIS, we performed a screen for microRNAs that can overcome or inhibit OIS in human diploid......-associated β-galactosidase. Moreover, cells with ectopic expression of miR-378a-5p retain proliferative capacity even in the presence of an activated Braf oncogene. Finally, we identified several miR-378a-5p targets in diploid fibroblasts that might explain the mechanism by which the microRNA can delay OIS. We...... speculate that miR-378a-5p might positively influence tumor formation by delaying OIS, which is consistent with a known pro-oncogenic function of this microRNA....

  10. Premature aging and immune senescence in HIV-infected children

    Science.gov (United States)

    Gianesin, Ketty; Noguera-Julian, Antoni; Zanchetta, Marisa; Del Bianco, Paola; Petrara, Maria Raffaella; Freguja, Riccardo; Rampon, Osvalda; Fortuny, Clàudia; Camós, Mireia; Mozzo, Elena; Giaquinto, Carlo; De Rossi, Anita

    2016-01-01

    Objective: Several pieces of evidence indicate that HIV-infected adults undergo premature aging. The effect of HIV and antiretroviral therapy (ART) exposure on the aging process of HIV-infected children may be more deleterious since their immune system coevolves from birth with HIV. Design: Seventy-one HIV-infected (HIV+), 65 HIV-exposed-uninfected (HEU), and 56 HIV-unexposed-uninfected (HUU) children, all aged 0–5 years, were studied for biological aging and immune senescence. Methods: Telomere length and T-cell receptor rearrangement excision circle levels were quantified in peripheral blood cells by real-time PCR. CD4+ and CD8+ cells were analysed for differentiation, senescence, and activation/exhaustion markers by flow cytometry. Results: Telomere lengths were significantly shorter in HIV+ than in HEU and HUU children (overall, P < 0.001 adjusted for age); HIV+ ART-naive (42%) children had shorter telomere length compared with children on ART (P = 0.003 adjusted for age). T-cell receptor rearrangement excision circle levels and CD8+ recent thymic emigrant cells (CD45RA+CD31+) were significantly lower in the HIV+ than in control groups (overall, P = 0.025 and P = 0.005, respectively). Percentages of senescent (CD28−CD57+), activated (CD38+HLA-DR+), and exhausted (PD1+) CD8+ cells were significantly higher in HIV+ than in HEU and HUU children (P = 0.004, P < 0.001, and P < 0.001, respectively). Within the CD4+ cell subset, the percentage of senescent cells did not differ between HIV+ and controls, but programmed cell death receptor-1 expression was upregulated in the former. Conclusions: HIV-infected children exhibit premature biological aging with accelerated immune senescence, which particularly affects the CD8+ cell subset. HIV infection per se seems to influence the aging process, rather than exposure to ART for prophylaxis or treatment. PMID:26990630

  11. Senescent heart compared with pressure overload-induced hypertrophy.

    Science.gov (United States)

    Assayag, P; Charlemagne, D; de Leiris, J; Boucher, F; Valère, P E; Lortet, S; Swynghedauw, B; Besse, S

    1997-01-01

    Although systolic left ventricular (LV) function is normal in the elderly, aging is associated in rat papillary muscle with mechanical and sarcoplasmic reticulum Ca2+ ATPase alterations similar to those observed in the hypertrophied heart. However, alterations in the other calcium-regulating proteins implicated in contraction and relaxation are still unknown. To investigate alterations in LV function and calcium-regulating proteins, we measured hemodynamics and Na(+)-Ca2+ exchanger (NCx), ryanodine receptor (RyR2), and sarcoplasmic reticular Ca2+ ATPase (SERCA2) mRNA levels (expressed in densitometric scores normalized to that of poly(A+) mRNA) in left ventricle from 4-month-old (adult, n = 13) and 24-month-old (senescent, n = 15) rats. For ex vivo contractile function, active tension was measured during isolated heart perfusion in adult (n = 11) and senescent (n = 11) rats. For comparison of age-dependent effects of moderate hypertension on both hemodynamics and calcium proteins, renovascular hypertension was induced or a sham operation performed at 2 (n = 11 and n = 6) and 22 (n = 26 and n = 5) months of age. In senescent rats, LV systolic pressure and maximal rates of pressure development were unaltered, although active tension was depressed (4.7 +/- 0.4 versus 8.3 +/- 0.7 g/g heart weight in adults, P < .0001). SERCA2 mRNA levels were decreased in senescent left ventricle (0.98 +/- 0.05 versus 1.18 +/- 0.05 in adults, P < .01), without changes in NCx and RyR2 mRNA accumulation. Renovascular hypertension resulted in 100% mortality in aged rats; in adults, renovascular hypertension resulted, 2 months later, in an increase of LV systolic pressure (170 +/- 7 versus 145 +/- 3 mm Hg in sham-operated rats, P < .05) and in mild LV hypertrophy (+18%, P < .01) associated with a decrease in SERCA2 mRNA levels (1.02 +/- 0.03 versus 1.18 +/- 0.03 in sham-operated rats, P < .001). Contractile dysfunction in senescent isolated heart and decreased SERCA2 mRNA levels were

  12. The emerging role of senescent cells in tissue homeostasis and pathophysiology

    Directory of Open Access Journals (Sweden)

    Kaoru Tominaga

    2015-05-01

    Full Text Available Cellular senescence is a state of permanent growth arrest and is thought to play a pivotal role in tumor suppression. Cellular senescence may play an important role in tumor suppression, wound healing, and protection against tissue fibrosis in physiological conditions in vivo. However, accumulating evidence that senescent cells may have harmful effects in vivo and may contribute to tissue remodeling, organismal aging, and many age-related diseases also exists. Cellular senescence can be induced by various intrinsic and extrinsic factors. Both p53/p21 and p16/RB pathways are important for irreversible growth arrest in senescent cells. Senescent cells secret numerous biologically active factors. This specific secretion phenotype by senescent cells may largely contribute to physiological and pathological consequences in organisms. Here I review the molecular basis of cell cycle arrest and the specific secretion phenotype in cellular senescence. I also summarize the current knowledge of the role of cellular senescence in vivo in physiological and pathological settings.

  13. Senescence-associated secretory phenotype and its possible role in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Kumar, Manish; Seeger, Werner; Voswinckel, Robert

    2014-09-01

    Chronic obstructive pulmonary disease (COPD) is a major disease of the lungs. It primarily occurs after a prolonged period of cigarette smoking. Chronic inflammation of airways and the alveolar space as well as lung tissue destruction are the hallmarks of COPD. Recently it has been shown that cellular senescence might play a role in the pathogenesis of COPD. Cellular senescence comprises signal transduction program, leading to irreversible cell cycle arrest. The growth arrest in senescence can be triggered by many different mechanisms, including DNA damage and its recognition by cellular sensors, leading to the activation of cell cycle checkpoint responses and activation of DNA repair machinery. Senescence can be induced by several genotoxic factors apart from telomere attrition. When senescence induction is based on DNA damage, senescent cells display a unique phenotype, which has been termed "senescence-associated secretory phenotype" (SASP). SASP may be an important driver of chronic inflammation and therefore may be part of a vicious cycle of inflammation, DNA damage, and senescence. This research perspective aims to showcase cellular senescence with relevance to COPD and the striking similarities between the mediators and secretory phenotype in COPD and SASP. PMID:25171460

  14. Replicative senescence in normal liver, chronic hepatitis C, and hepatocellular carcinomas.

    Science.gov (United States)

    Paradis, V; Youssef, N; Dargère, D; Bâ, N; Bonvoust, F; Deschatrette, J; Bedossa, P

    2001-03-01

    There is growing evidence that senescent cells accumulate in vivo and are associated with the aging process in parallel with the progressive erosion of telomeres. Because recent data show that telomere shortening is involved in the pathogenesis of liver cirrhosis, we looked for replicative senescence cells in normal livers, chronic hepatitis C, and hepatocellular carcinoma (HCC). Replicative senescent cells were detected on liver tissue cryosections using expression of a specific marker, senescence-associated beta-galactosidase, a cytoplasmic enzyme detected at pH 6. A total of 57 frozen liver samples (15 normal liver, 32 chronic hepatitis C, and 10 HCCs) were studied. Replicative senescence was graded as absent in 56% of cases (32 of 57) and present in 44% (25 of 57). Replicative senescence was considered present in 3 of 15 normal livers (20%), 16 of 32 chronic hepatitis cases (50%), and 6 of 10 HCCs (60%). In the group of nontumoral livers, the presence of senescent cells in liver was associated with older age (P =.03). In the group with chronic hepatitis C, fibrosis stage, but not activity grade, was significantly correlated with the accumulation of replicative senescent cells (P HCC in the surrounding liver (P HCC development. Detection of replicative senescent cells may then serve as a predictive marker of a hepatocellular carcinoma in the surrounding tissue. HUM PATHOL 32:327-332. PMID:11274643

  15. Mitochondrial DNA deletion and impairment of mitochondrial biogenesis are mediated by reactive oxygen species in ionizing radiation-induced premature senescence

    International Nuclear Information System (INIS)

    Mitochondrial DNA (mtDNA) deletion is a well-known marker for oxidative stress and aging, and contributes to harmful effects in cultured cells and animal tissues. mtDNA biogenesis genes (NRF-1, TFAM) are essential for the maintenance of mtDNA, as well as the transcription and replication of mitochondrial genomes. Considering that oxidative stress is known to affect mitochondrial biogenesis, we hypothesized that ionizing radiation (IR)-induced reactive oxygen species (ROS) causes mtDNA deletion by modulating the mitochondrial biogenesis, thereby leading to cellular senescence. Therefore, we examined the effects of IR on ROS levels, cellular senescence, mitochondrial biogenesis, and mtDNA deletion in IMR-90 human lung fibroblast cells. Young IMR-90 cells at population doubling (PD) 39 were irradiated at 4 or 8 Gy. Old cells at PD55, and H2O2-treated young cells at PD 39, were compared as a positive control. The IR increased the intracellular ROS level, senescence-associated β-galactosidase (SA-β-gal) activity, and mtDNA common deletion (4977 bp), and it decreased the mRNA expression of NRF-1 and TFAM in IMR-90 cells. Similar results were also observed in old cells (PD 55) and H2O2-treated young cells. To confirm that a increase in ROS level is essential for mtDNA deletion and changes of mitochondrial biogenesis in irradiated cells, the effects of N-acetylcysteine (NAC) were examined. In irradiated and H2O2-treated cells, 5 mM NAC significantly attenuated the increases of ROS, mtDNA deletion, and SA-β-gal activity, and recovered from decreased expressions of NRF-1 and TFAM mRNA. These results suggest that ROS is a key cause of IR-induced mtDNA deletion, and the suppression of the mitochondrial biogenesis gene may mediate this process.

  16. Mitochondrial DNA deletion and impairment of mitochondrial biogenesis are mediated by reactive oxygen species in ionizing radiation-induced premature senescence

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Hyeon Soo; Jung, U Hee; Jo, Sung Kee [Radiation Biotechnology Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Young Sang [College of Natural Sciences, Chungnam National University, Daejeon (Korea, Republic of)

    2011-09-15

    Mitochondrial DNA (mtDNA) deletion is a well-known marker for oxidative stress and aging, and contributes to harmful effects in cultured cells and animal tissues. mtDNA biogenesis genes (NRF-1, TFAM) are essential for the maintenance of mtDNA, as well as the transcription and replication of mitochondrial genomes. Considering that oxidative stress is known to affect mitochondrial biogenesis, we hypothesized that ionizing radiation (IR)-induced reactive oxygen species (ROS) causes mtDNA deletion by modulating the mitochondrial biogenesis, thereby leading to cellular senescence. Therefore, we examined the effects of IR on ROS levels, cellular senescence, mitochondrial biogenesis, and mtDNA deletion in IMR-90 human lung fibroblast cells. Young IMR-90 cells at population doubling (PD) 39 were irradiated at 4 or 8 Gy. Old cells at PD55, and H2O2-treated young cells at PD 39, were compared as a positive control. The IR increased the intracellular ROS level, senescence-associated {beta}-galactosidase (SA-{beta}-gal) activity, and mtDNA common deletion (4977 bp), and it decreased the mRNA expression of NRF-1 and TFAM in IMR-90 cells. Similar results were also observed in old cells (PD 55) and H{sub 2}O{sub 2}-treated young cells. To confirm that a increase in ROS level is essential for mtDNA deletion and changes of mitochondrial biogenesis in irradiated cells, the effects of N-acetylcysteine (NAC) were examined. In irradiated and H{sub 2}O{sub 2}-treated cells, 5 mM NAC significantly attenuated the increases of ROS, mtDNA deletion, and SA-{beta}-gal activity, and recovered from decreased expressions of NRF-1 and TFAM mRNA. These results suggest that ROS is a key cause of IR-induced mtDNA deletion, and the suppression of the mitochondrial biogenesis gene may mediate this process.

  17. Fibroblast cultures in duchenne muscular dystrophy

    International Nuclear Information System (INIS)

    Primary skin fibroblast cultures were grown from forearm pinch skin biopsies obtained from 24 patients with Duchenne muscular dystrophy (DMD) and ten normal controls matched for sex and age. The first subcultures were grown for 7 days and incubated with L-(3H)-proline for 24 hours. Intracellular collagen incoption was significantly decreased (2.2 X) and extracellular collagen incorporation significantly increased (1.8 X) in fibroblast cultures from patients with DMD by both collagenase assay and polyacrylamide gel electrophoresis. The synthesis of noncollagen proteins showed low values from the DMD fibroblast cultures. The alterations in synthesis and secretion of collagen and noncollagen proteins were characteristic only for the log phase of DMD fibroblasts. (author)

  18. Differences in motility pattern between human buccal fibroblasts and periodontal and skin fibroblasts

    DEFF Research Database (Denmark)

    Lepekhin, Eugene; Grøn, Birgitte; Berezin, Vladimir;

    2002-01-01

    -assisted microscope work-station. For evaluation of cell morphology, cell contours were recognized semiautomatically and used for determination of cell area, cell spreading and number and length of processes. We found that the cellular displacement of the buccal fibroblasts was only approximately 50% of the cellular...... displacement of periodontal and skin fibroblasts. The decreased cellular displacement of the buccal fibroblasts was found to be due to both lower cellular speed and less persistence in direction. The buccal fibroblasts also displayed smaller areas and longer processes. The differences in cellular morphology...

  19. The β-carboline alkaloid harmine inhibits telomerase activity of MCF-7 cells by down-regulating hTERT mRNA expression accompanied by an accelerated senescent phenotype

    Directory of Open Access Journals (Sweden)

    Lei Zhao

    2013-10-01

    Full Text Available The end replication problem, which occurs in normal somatic cells inducing replicative senescence, is solved in most cancer cells by activating telomerase. The activity of telomerase is highly associated with carcinogenesis which makes the enzyme an attractive biomarker in cancer diagnosis and treatment. The indole alkaloid harmine has multiple pharmacological properties including DNA intercalation which can lead to frame shift mutations. In this study, harmine was applied to human breast cancer MCF-7 cells. Its activity towards telomerase was analyzed by utilizing the telomeric repeat amplification protocol (TRAP. Our data indicate that harmine exhibits a pronounced cytotoxicity and induces an anti-proliferation state in MCF-7 cells which is accompanied by a significant inhibition of telomerase activity and an induction of an accelerated senescence phenotype by over-expressing elements of the p53/p21 pathway.

  20. Antroquinonol, a natural ubiquinone derivative, induces a cross talk between apoptosis, autophagy and senescence in human pancreatic carcinoma cells.

    Science.gov (United States)

    Yu, Chia-Chun; Chiang, Po-Cheng; Lu, Pin-Hsuan; Kuo, Mao-Tien; Wen, Wu-Che; Chen, Peini; Guh, Jih-Hwa

    2012-08-01

    Pancreatic cancer is a malignant neoplasm of the pancreas. A mutation and constitutive activation of K-ras occurs in more than 90% of pancreatic adenocarcinomas. A successful approach for the treatment of pancreatic cancers is urgent. Antroquinonol, a ubiquinone derivative isolated from a camphor tree mushroom, Antrodia camphorata, induced a concentration-dependent inhibition of cell proliferation in pancreatic cancer PANC-1 and AsPC-1 cells. Flow cytometric analysis of DNA content by propidium iodide staining showed that antroquinonol induced G1 arrest of the cell cycle and a subsequent apoptosis. Antroquinonol inhibited Akt phosphorylation at Ser(473), the phosphorylation site critical for Akt kinase activity, and blocked the mammalian target of rapamycin (mTOR) phosphorylation at Ser(2448), a site dependent on mTOR activity. Several signals responsible for mTOR/p70S6K/4E-BP1 signaling cascades have also been examined to validate the pathway. Moreover, antroquinonol induced the down-regulation of several cell cycle regulators and mitochondrial antiapoptotic proteins. In contrast, the expressions of K-ras and its phosphorylation were significantly increased. The coimmunoprecipitation assay showed that the association of K-ras and Bcl-xL was dramatically augmented, which was indicative of apoptotic cell death. Antroquinonol also induced the cross talk between apoptosis, autophagic cell death and accelerated senescence, which was, at least partly, explained by the up-regulation of p21(Waf1/Cip1) and K-ras. In summary, the data suggest that antroquinonol induces anticancer activity in human pancreatic cancers through an inhibitory effect on PI3-kinase/Akt/mTOR pathways that in turn down-regulates cell cycle regulators. The translational inhibition causes G1 arrest of the cell cycle and an ultimate mitochondria-dependent apoptosis. Moreover, autophagic cell death and accelerated senescence also explain antroquinonol-mediated anticancer effect. PMID:21840189

  1. Coupling of cytoskeleton functions for fibroblast locomotion

    DEFF Research Database (Denmark)

    Couchman, J R; Lenn, M; Rees, D A

    1985-01-01

    Using a chick cell phenotype specialised for locomotion with morphometric measurements made possible by modern instrumentation technology, we have reinvestigated motile functions in fibroblast locomotion. Quantitative analysis of rapid fluctuations in cell form and organelle distribution during l...... function of microtubules to direct the flow towards multiple foci on the leading edge, and so determine cell polarity. Such a mechanism of locomotion for fibroblasts has many features consistent with evidence for other cell types, especially amoebae and leukocytes....

  2. Modulation of Gingival Fibroblast Minocycline Accumulation by Biological Mediators

    OpenAIRE

    Walters, J.D.; Nakkula, R.J.; Maney, P.

    2005-01-01

    Gingival fibroblasts actively accumulate tetracyclines, thereby enhancing their redistribution from blood to gingiva. Since growth factors and pro-inflammatory cytokines regulate many fibroblast activities, they could potentially enhance fibroblast minocycline accumulation. To test this hypothesis, we treated gingival fibroblast monolayers for 1 or 6 hours with platelet-derived growth factor-BB (PDGF), fibroblast growth factor-2 (FGF), transforming growth factor-β1 (TGF), or tumor necrosis fa...

  3. The common properties and the heterogeneity of dermal fibroblast subpopulations.

    OpenAIRE

    Makarchuk O.I.

    2007-01-01

    Dermal fibroblasts are a dynamic and diverse population of cells whose functions in skin in many respects remain unknown. Normal adult human skin contains at least three distinct subpopulations of fibroblasts, which occupy unique niches in the dermis. Fibroblasts from each of these niches exhibit distinctive differences when cultured separately. Specific differences in fibroblast histophysiology are evident in papillary dermal fibroblasts, which reside in the superficial dermis, and reticular...

  4. Biosynthesis of fibronectin by human embryo fibroblasts

    International Nuclear Information System (INIS)

    The biosynthesis of fibronectin by human embryo fibroblasts, transformed by SV-40 virus, was investigated in intact cells and in a cell-free protein-synthesizing system on free and membrane-bound polyribosomes, isolated from the same cells. It was shown that fibronectin production in the culture medium by transformed fibroblasts is reduced by a factor of 4.5, while its percent content in the medium is decreased by a factor of 2. The content of fibronectin material precipitable by antibodies during the immunoprecipitation reaction proved to be somewhat greater in transformed cells than in normal cells, although the percentage was decreased by a factor of 1.5. However, the content of the fibronectin monomer with molecular weight 220 kilodaltons was 1.6 times as great in the cellular material of normal fibroblasts. In an investigation of fibronectin biosynthesis in a cell-free system it was established that in transformed cells 45% of the fibronectin is synthesized on free polyribosomes; in normal fibroblasts only 13% of the fibronectin is synthesized on free polyribosomes. It is suggested that one of the consequences of the transformation of human fibroblasts by SV-40 virus, leading to a decrease in fibronectin production, is the spatial uncoupling of the polyribosomes and membrane structures responsible for protein transport out of the cell, as a result of which a substantial portion of the fibronectin synthesized by transformed fibroblasts is subjected to intracellular degradation

  5. Telomerase inhibition by siRNA causes senescence and apoptosis in Barrett's adenocarcinoma cells: mechanism and therapeutic potential

    Directory of Open Access Journals (Sweden)

    Batchu Ramesh B

    2005-07-01

    Full Text Available Abstract Background In cancer cells, telomerase induction helps maintain telomere length and thereby bypasses senescence and provides enhanced replicative potential. Chemical inhibitors of telomerase have been shown to reactivate telomere shortening and cause replicative senescence and apoptotic cell death of tumor cells while having little or no effect on normal diploid cells. Results We designed siRNAs against two different regions of telomerase gene and evaluated their effect on telomere length, proliferative potential, and gene expression in Barrett's adenocarcinoma SEG-1 cells. The mixture of siRNAs in nanomolar concentrations caused a loss of telomerase activity that appeared as early as day 1 and was essentially complete at day 3. Inhibition of telomerase activity was associated with marked reduction in median telomere length and complete loss of detectable telomeres in more than 50% of the treated cells. Telomere loss caused senescence in 40% and apoptosis in 86% of the treated cells. These responses appeared to be associated with activation of DNA sensor HR23B and subsequent activation of p53 homolog p73 and p63 and E2F1. Changes in these gene regulators were probably the source of observed up-regulation of cell cycle inhibitors, p16 and GADD45. Elevated transcript levels of FasL, Fas and caspase 8 that activate death receptors and CARD 9 that interacts with Bcl10 and NFKB to enhance mitochondrial translocation and activation of caspase 9 were also observed. Conclusion These studies show that telomerase siRNAs can cause effective suppression of telomerase and telomere shortening leading to both cell cycle arrest and apoptosis via mechanisms that include up-regulation of several genes involved in cell cycle arrest and apoptosis. Telomerase siRNAs may therefore be strong candidates for highly selective therapy for chemoprevention and treatment of Barrett's adenocarcinoma.

  6. Cancer

    Science.gov (United States)

    ... Blood tests (which look for chemicals such as tumor markers) Bone marrow biopsy (for lymphoma or leukemia) Chest ... the case with skin cancers , as well as cancers of the lung, breast, and colon. If the tumor has spread ...

  7. Cancer

    Science.gov (United States)

    Cancer begins in your cells, which are the building blocks of your body. Normally, your body forms ... be benign or malignant. Benign tumors aren't cancer while malignant ones are. Cells from malignant tumors ...

  8. Differential effects on cell motility, embryonic stem cell self-renewal and senescence by diverse Src kinase family inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Tamm, Christoffer, E-mail: christoffer.tamm@imbim.uu.se; Galito, Sara Pijuan, E-mail: sara.pijuan@imbim.uu.se; Anneren, Cecilia, E-mail: cecilia.anneren@imbim.uu.se

    2012-02-15

    The Src family of non-receptor tyrosine kinases (SFKs) has been shown to play an intricate role in embryonic stem (ES) cell maintenance. In the present study we have focused on the underlying molecular mechanisms responsible for the vastly different effects induced by various commonly used SFK inhibitors. We show that several diverse cell types, including fibroblasts completely lacking SFKs, cannot undergo mitosis in response to SU6656 and that this is caused by an unselective inhibition of Aurora kinases. In contrast, PP2 and PD173952 block motility immediately upon exposure and forces cells to grow in dense colonies. The subsequent halt in proliferation of fibroblast and epithelial cells in the center of the colonies approximately 24 h post-treatment appears to be caused by cell-to-cell contact inhibition rather than a direct effect of SFK kinase inhibition. Interestingly, in addition to generating more homogenous and dense ES cell cultures, without any diverse effect on proliferation, PP2 and PD173652 also promote ES cell self-renewal by reducing the small amount of spontaneous differentiation typically observed under standard ES cell culture conditions. These effects could not be mirrored by the use of Gleevec, a potent inhibitor of c-Abl and PDGFR kinases that are also inhibited by PP2. -- Highlights: Black-Right-Pointing-Pointer SFK inhibitor SU6656 induces senescence in mouse ES cells. Black-Right-Pointing-Pointer SU6656 inhibits mitosis in a SFK-independent manner via cross-selectivity for Aurora kinases. Black-Right-Pointing-Pointer SFK inhibitor PP2 impairs cell motility in various cell lines, including mouse ES cells. Black-Right-Pointing-Pointer Ensuing impeded motility, PP2 inhibits proliferation of various cells lines except for mouse ES cells. Black-Right-Pointing-Pointer SFK inhibitors PP2 and PD173952 impede spontaneous differentiation in standard mouse ES culture maintenance.

  9. Differential effects on cell motility, embryonic stem cell self-renewal and senescence by diverse Src kinase family inhibitors

    International Nuclear Information System (INIS)

    The Src family of non-receptor tyrosine kinases (SFKs) has been shown to play an intricate role in embryonic stem (ES) cell maintenance. In the present study we have focused on the underlying molecular mechanisms responsible for the vastly different effects induced by various commonly used SFK inhibitors. We show that several diverse cell types, including fibroblasts completely lacking SFKs, cannot undergo mitosis in response to SU6656 and that this is caused by an unselective inhibition of Aurora kinases. In contrast, PP2 and PD173952 block motility immediately upon exposure and forces cells to grow in dense colonies. The subsequent halt in proliferation of fibroblast and epithelial cells in the center of the colonies approximately 24 h post-treatment appears to be caused by cell-to-cell contact inhibition rather than a direct effect of SFK kinase inhibition. Interestingly, in addition to generating more homogenous and dense ES cell cultures, without any diverse effect on proliferation, PP2 and PD173652 also promote ES cell self-renewal by reducing the small amount of spontaneous differentiation typically observed under standard ES cell culture conditions. These effects could not be mirrored by the use of Gleevec, a potent inhibitor of c-Abl and PDGFR kinases that are also inhibited by PP2. -- Highlights: ► SFK inhibitor SU6656 induces senescence in mouse ES cells. ► SU6656 inhibits mitosis in a SFK-independent manner via cross-selectivity for Aurora kinases. SFK inhibitor PP2 impairs cell motility in various cell lines, including mouse ES cells. ► Ensuing impeded motility, PP2 inhibits proliferation of various cells lines except for mouse ES cells. ► SFK inhibitors PP2 and PD173952 impede spontaneous differentiation in standard mouse ES culture maintenance.

  10. Genome-wide transcriptional reorganization associated with senescence-to-immortality switch during human hepatocellular carcinogenesis.

    Directory of Open Access Journals (Sweden)

    Gokhan Yildiz

    Full Text Available Senescence is a permanent proliferation arrest in response to cell stress such as DNA damage. It contributes strongly to tissue aging and serves as a major barrier against tumor development. Most tumor cells are believed to bypass the senescence barrier (become "immortal" by inactivating growth control genes such as TP53 and CDKN2A. They also reactivate telomerase reverse transcriptase. Senescence-to-immortality transition is accompanied by major phenotypic and biochemical changes mediated by genome-wide transcriptional modifications. This appears to happen during hepatocellular carcinoma (HCC development in patients with liver cirrhosis, however, the accompanying transcriptional changes are virtually unknown. We investigated genome-wide transcriptional changes related to the senescence-to-immortality switch during hepatocellular carcinogenesis. Initially, we performed transcriptome analysis of senescent and immortal clones of Huh7 HCC cell line, and identified genes with significant differential expression to establish a senescence-related gene list. Through the analysis of senescence-related gene expression in different liver tissues we showed that cirrhosis and HCC display expression patterns compatible with senescent and immortal phenotypes, respectively; dysplasia being a transitional state. Gene set enrichment analysis revealed that cirrhosis/senescence-associated genes were preferentially expressed in non-tumor tissues, less malignant tumors, and differentiated or senescent cells. In contrast, HCC/immortality genes were up-regulated in tumor tissues, or more malignant tumors and progenitor cells. In HCC tumors and immortal cells genes involved in DNA repair, cell cycle, telomere extension and branched chain amino acid metabolism were up-regulated, whereas genes involved in cell signaling, as well as in drug, lipid, retinoid and glycolytic metabolism were down-regulated. Based on these distinctive gene expression features we developed a 15

  11. Genome-wide transcriptional reorganization associated with senescence-to-immortality switch during human hepatocellular carcinogenesis.

    Science.gov (United States)

    Yildiz, Gokhan; Arslan-Ergul, Ayca; Bagislar, Sevgi; Konu, Ozlen; Yuzugullu, Haluk; Gursoy-Yuzugullu, Ozge; Ozturk, Nuri; Ozen, Cigdem; Ozdag, Hilal; Erdal, Esra; Karademir, Sedat; Sagol, Ozgul; Mizrak, Dilsa; Bozkaya, Hakan; Ilk, Hakki Gokhan; Ilk, Ozlem; Bilen, Biter; Cetin-Atalay, Rengul; Akar, Nejat; Ozturk, Mehmet

    2013-01-01

    Senescence is a permanent proliferation arrest in response to cell stress such as DNA damage. It contributes strongly to tissue aging and serves as a major barrier against tumor development. Most tumor cells are believed to bypass the senescence barrier (become "immortal") by inactivating growth control genes such as TP53 and CDKN2A. They also reactivate telomerase reverse transcriptase. Senescence-to-immortality transition is accompanied by major phenotypic and biochemical changes mediated by genome-wide transcriptional modifications. This appears to happen during hepatocellular carcinoma (HCC) development in patients with liver cirrhosis, however, the accompanying transcriptional changes are virtually unknown. We investigated genome-wide transcriptional changes related to the senescence-to-immortality switch during hepatocellular carcinogenesis. Initially, we performed transcriptome analysis of senescent and immortal clones of Huh7 HCC cell line, and identified genes with significant differential expression to establish a senescence-related gene list. Through the analysis of senescence-related gene expression in different liver tissues we showed that cirrhosis and HCC display expression patterns compatible with senescent and immortal phenotypes, respectively; dysplasia being a transitional state. Gene set enrichment analysis revealed that cirrhosis/senescence-associated genes were preferentially expressed in non-tumor tissues, less malignant tumors, and differentiated or senescent cells. In contrast, HCC/immortality genes were up-regulated in tumor tissues, or more malignant tumors and progenitor cells. In HCC tumors and immortal cells genes involved in DNA repair, cell cycle, telomere extension and branched chain amino acid metabolism were up-regulated, whereas genes involved in cell signaling, as well as in drug, lipid, retinoid and glycolytic metabolism were down-regulated. Based on these distinctive gene expression features we developed a 15-gene

  12. 人类成纤维细胞生长因子受体1的Ⅲb亚型在胰腺癌细胞中的作用%The role of human fibroblast growth factor receptor 1-Ⅲb isoform in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    刘占兵; 杨尹默; 乔岐禄; 赵建勋; 黄莚庭; Marko Kornmann

    2007-01-01

    Objective To study the role of Ⅲb isoform of human fibroblast growth factor receptor 1 (FGFR1-Ⅲb) in PANC-1 pancreatic cancer cells. Methods The plasmid of human full-length FGFR1-Ⅲb isoform,pSVK4/FGFR1-Ⅲb, was stable transfected into cultured PNAC-1 pancreatic cancer cell lines facilitated by lipofectamine. The function of FGFR1-Ⅲb in transfected pancreatic cancer cells were examined by MTT assay, soft agar assay, cell migration assay, single cell movement assay, In vivo tumorigenicity assay. Results The basal anchorage-dependent and -independent cell growth was significantly inhibited. Additionally, FGFR1-Ⅲb expression inhibited single cell movement and in vitro invasion as determined by time-lapse microscopy and boyden chamber assay as well as in vivo tumor formation and growth in nude mice. Microscopic analysis of the xenograft tumors revealed a reduced Ki-67 labelling, lower amount of tumor necrosis and higher grade of differentiation in FGFR1-Ⅲb expressing tumors. Conclusion We identified a functional human FGFR mRNA splice variant that inhibits the transforming potential of pancreatic cancer cells.%目的 探讨人类成纤维细胞生长因子受体1的Ⅲb亚型(FGFR1-Ⅲb)在胰腺癌细胞中的作用. 方法 以脂质体法将人类全长FGFR1-Ⅲb表达质粒pSVK4/FGFR1-Ⅲb稳定转染入PANC-1胰腺癌细胞,通过MTT试验、软琼脂试验、细胞迁移试验、单个细胞运动试验和裸鼠移植瘤试验检测FGFR1-Ⅲb在转染的胰腺癌细胞中的功能. 结果 转染FGFR1-Ⅲb受体的胰腺癌细胞,在细胞生长、细胞迁移、细胞运动、移植瘤形成及生长方面均受抑,且移植瘤Ki-67表达减低、肿瘤组织中坏死灶减少. 结论 人类FGFR1-Ⅲb受体为胰腺癌细胞的功能性受体,对胰腺癌细胞具有抑制作用.

  13. JNK inhibition sensitizes tumor cells to radiation-induced premature senescence via Bcl-2/ROS/DDR signaling pathway

    International Nuclear Information System (INIS)

    Premature senescence is considered as a cellular defense mechanism to prevent tumorigenesis. Although recent evidences demonstrate that c-Jun N-terminal kinase (JNK) is involved in the senescence process, the target and exact mechanism of JNK signaling in the regulation of cell proliferation has yet to be defined. In this study, we investigated the role of JNK in premature senescence and demonstrated JNK inhibition sensitized tumor cells to radiation-induced premature senescence

  14. Early Autumn Senescence in Red Maple (Acer rubrum L. Is Associated with High Leaf Anthocyanin Content

    Directory of Open Access Journals (Sweden)

    Rachel Anderson

    2015-08-01

    Full Text Available Several theories exist about the role of anthocyanins in senescing leaves. To elucidate factors contributing to variation in autumn leaf anthocyanin contents among individual trees, we analysed anthocyanins and other leaf traits in 27 individuals of red maple (Acer rubrum L. over two growing seasons in the context of timing of leaf senescence. Red maple usually turns bright red in the autumn, but there is considerable variation among the trees. Leaf autumn anthocyanin contents were consistent between the two years of investigation. Autumn anthocyanin content strongly correlated with degree of chlorophyll degradation mid to late September, early senescing leaves having the highest concentrations of anthocyanins. It also correlated positively with leaf summer chlorophyll content and dry matter content, and negatively with specific leaf area. Time of leaf senescence and anthocyanin contents correlated with soil pH and with canopy openness. We conclude that the importance of anthocyanins in protection of leaf processes during senescence depends on the time of senescence. Rather than prolonging the growing season by enabling a delayed senescence, autumn anthocyanins in red maple in Ontario are important when senescence happens early, possibly due to the higher irradiance and greater danger of oxidative damage early in the season.

  15. Dominant Gene cplsr1 Corresponding to Premature Leaf Senescence Resistance in Cotton (Gossypium hirsutum L.)

    Institute of Scientific and Technical Information of China (English)

    Jingqing Zhao; Tengfei Jiang; Zhi Liu; Wenwei Zhang; Guiliang Jian; Fangjun Qi

    2012-01-01

    Cotton (Gossypium hirsutum L.) premature leaf senescence-resistant inbred XLZ33 and senescencesusceptible inbred lines XLZ13 were selected and crossed to produce F1,F1-reciprocal,F2 and BC1 generations for evaluation of leaf senescence process and inheritance.The results showed that leaf senescence processes for XLZ13 and XLZ33 were obviously different and leaf senescence traits could be distinguished between the two parents at particular periods of cotton growth.Inheritance anlysis for the cotton premature leaf senescence resistant trait further showed that the segregation in the F2 fit a 3:1 ratio inheritance pattern,with resistance being dominant.The backcross of F1 to the susceptible parent produced a 1:1 ratio,confirming that cotton premature leaf senescence resistant trait was from a single gene.The single dominant gene controlling cotton premature leaf senescence resistance in XLZ33 was named as cotton premature leaf senescence resistance 1,with the symbol cplsr1.

  16. Purple sweet potato color inhibits endothelial premature senescence by blocking the NLRP3 inflammasome.

    Science.gov (United States)

    Sun, Chunhui; Fan, Shaohua; Wang, Xin; Lu, Jun; Zhang, Zifeng; Wu, Dongmei; Shan, Qun; Zheng, Yuanlin

    2015-10-01

    Purple sweet potato color (PSPC), flavonoids isolated from purple sweet potato, has been well demonstrated for the pharmacological properties. In the present study, we attempt to explore whether the antisenescence was involved in PSPC-mediated protection against endothelium dysfunction in type 2 diabetes mellitus (T2DM) and, if involved, what are the possible mechanisms. The results showed that atherogenesis and endothelial senescence in the thoracic aorta were promoted in mice with prediabetes; meanwhile, PSPC attenuated the deterioration of vascular vessel and inhibited the endothelial senescence. Diabetes mellitus is a documented high-risk factor for the development of atherosclerosis. Studies show that D-galactose (D-gal) promotes endothelial cell senescence in vitro. In our study, we have determined that PSPC could suppress the D-gal-induced premature senescence and the abnormal endothelial function, discovered in the early stages of atherosclerosis induced by T2DM. We have discovered that the PSPC down-regulates reactive oxygen species (ROS) accumulation and the NLRP3 inflammasome functions. Furthermore, the premature senescence induced by D-gal was inhibited after attenuation of ROS and deactivation of NLRP3 inflammasomes. However, once the NLRP3 inflammasomes are overactivated, PSPC could not restrain cell senescence. These data imply that the beneficial effects of PSPC on diabetes-induced endothelial dysfunction and senescence are mediated through ROS and NLRP3 signaling pathways, suggesting a potential target for the prevention of endothelial senescence-related cardiovascular diseases. PMID:26164602

  17. Cytokine expression and signaling in drug-induced cellular senescence

    Czech Academy of Sciences Publication Activity Database

    Nováková, Zora; Hubáčková, Soňa; Košař, Martin; Janderová-Rossmeislová, Lenka; Dobrovolná, Jana; Vašicová, Pavla; Vančurová, Markéta; Hořejší, Zuzana; Hozák, Pavel; Bartek, Jiří; Hodný, Zdeněk

    2010-01-01

    Roč. 29, č. 2 (2010), s. 273-284. ISSN 0950-9232 R&D Projects: GA AV ČR IAA500390501; GA ČR GA204/08/1418; GA MŠk LC545 Grant ostatní: EC(XE) TRIREME Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50200510 Keywords : cellular senescence * cytokines * JAK/STAT signaling pathway Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.414, year: 2010

  18. Biological age and rates of senescence of organism of students

    Directory of Open Access Journals (Sweden)

    Loshits'ka T.I.

    2010-07-01

    Full Text Available Correlations of biological and passport age of student young people are considered. In an experiment took part 25 students by age 17-19 years. The calculation of their biological age is conducted. The rates of senescence of organism of students are appraised. Indexes which have the strongest connection with the index of biological age are certain. The got results are compared to information of researchers of other regions of Ukraine. The prospects of health work are offered on physical education for adjustment of difference between biological and passport age.

  19. TAp73 promotes anti-senescence-anabolism not proliferation

    Science.gov (United States)

    Agostini, Massimiliano; Niklison-Chirou, Maria Victoria; Catani, Maria Valeria; Knight, Richard A.; Melino, Gerry; Rufini, Alessandro

    2014-01-01

    TAp73, a member of the p53 family, has been traditionally considered a tumor suppressor gene, but a recent report has claimed that it can promote cel