WorldWideScience

Sample records for cell proliferative fate

  1. PUF-8, a Pumilio Homolog, Inhibits the Proliferative Fate in the Caenorhabditis elegans Germline

    OpenAIRE

    Racher, Hilary; Hansen, Dave

    2012-01-01

    Stem cell populations are maintained by keeping a balance between self-renewal (proliferation) and differentiation of dividing stem cells. Within the Caenorhabditis elegans germline, the key regulator maintaining this balance is the canonical Notch signaling pathway, with GLP-1/Notch activity promoting the proliferative fate. We identified the Pumilio homolog, PUF-8, as an inhibitor of the proliferative fate of stem cells in the C. elegans germline. puf-8(0) strongly enhances overproliferatio...

  2. PUF-8, a Pumilio homolog, inhibits the proliferative fate in the Caenorhabditis elegans germline.

    Science.gov (United States)

    Racher, Hilary; Hansen, Dave

    2012-10-01

    Stem cell populations are maintained by keeping a balance between self-renewal (proliferation) and differentiation of dividing stem cells. Within the Caenorhabditis elegans germline, the key regulator maintaining this balance is the canonical Notch signaling pathway, with GLP-1/Notch activity promoting the proliferative fate. We identified the Pumilio homolog, PUF-8, as an inhibitor of the proliferative fate of stem cells in the C. elegans germline. puf-8(0) strongly enhances overproliferation of glp-1(gf) mutants and partially suppresses underproliferation of a weak glp-1(lf) mutant. The germline tumor that is formed in a puf-8(0); glp-1(gf) double mutant is due to a failure of germ cells to enter meiotic prophase. puf-8 likely inhibits the proliferative fate through negatively regulating GLP-1/Notch signaling or by functioning parallel to it. PMID:23050230

  3. Proliferative capacity of murine hematopoietic stem cells

    International Nuclear Information System (INIS)

    The present study demonstrates a decrease in self-renewal capacity with serial transfer of murine hematopoietic stem cells. Production of differentiated cell progeny is maintained longer than stem cell self-renewal. In normal animals the capacity for self-renewal is not decreased with increasing donor age. The stem cell compartment in normal animals, both young and old, appears to be proliferatively quiescent. After apparent recovery from the alkylating agent busulfan, the probability of stem cell self-renewal is decreased, there is a permanent defect in the capacity of the bone marrow for serial transplantation, and the stem cells are proliferatively active. These findings support a model of the hematopoietic stem cell compartment as a continuum of cells with decreasing capacities for self-renewal, increasing likelihood for differentiation, and increasing proliferative activity. Cells progress in the continuum in one direction and such progression is not reversible

  4. Divergent Paths Lnc Cell Fates.

    Science.gov (United States)

    Ounzain, Samir; Pedrazzini, Thierry

    2016-05-01

    Long noncoding RNAs (lncRNAs) comprise a class of regulatory molecules that may control diverse stem cell properties. Now in Cell Stem Cell, Luo et al. (2016) show that a specific group of lncRNAs, those transcribed divergently from protein coding genes, activate key developmental genes to control embryonic stem cell fate. PMID:27152437

  5. Th1 and Th17 cells induce proliferative glomerulonephritis.

    Science.gov (United States)

    Summers, Shaun A; Steinmetz, Oliver M; Li, Ming; Kausman, Joshua Y; Semple, Timothy; Edgtton, Kristy L; Borza, Dorin-Bogdan; Braley, Hal; Holdsworth, Stephen R; Kitching, A Richard

    2009-12-01

    Th1 effector CD4+ cells contribute to the pathogenesis of proliferative and crescentic glomerulonephritis, but whether effector Th17 cells also contribute is unknown. We compared the involvement of Th1 and Th17 cells in a mouse model of antigen-specific glomerulonephritis in which effector CD4+ cells are the only components of adaptive immunity that induce injury. We planted the antigen ovalbumin on the glomerular basement membrane of Rag1(-/-) mice using an ovalbumin-conjugated non-nephritogenic IgG1 monoclonal antibody against alpha3(IV) collagen. Subsequent injection of either Th1- or Th17-polarized ovalbumin-specific CD4+ effector cells induced proliferative glomerulonephritis. Mice injected with Th1 cells developed progressive albuminuria over 21 d, histologic injury including 5.5 +/- 0.9% crescent formation/segmental necrosis, elevated urinary nitrate, and increased renal NOS2, CCL2, and CCL5 mRNA. Mice injected with Th17 cells developed albuminuria by 3 d; compared with Th1-injected mice, their glomeruli contained more neutrophils and greater expression of renal CXCL1 mRNA. In conclusion, Th1 and Th17 effector cells can induce glomerular injury. Understanding how these two subsets mediate proliferative forms of glomerulonephritis may lead to targeted therapies. PMID:19820122

  6. Muscle Stem Cell Fate Is Controlled by the Cell-Polarity Protein Scrib

    Directory of Open Access Journals (Sweden)

    Yusuke Ono

    2015-02-01

    Full Text Available Satellite cells are resident skeletal muscle stem cells that supply myonuclei for homeostasis, hypertrophy, and repair in adult muscle. Scrib is one of the major cell-polarity proteins, acting as a potent tumor suppressor in epithelial cells. Here, we show that Scrib also controls satellite-cell-fate decisions in adult mice. Scrib is undetectable in quiescent cells but becomes expressed during activation. Scrib is asymmetrically distributed in dividing daughter cells, with robust accumulation in cells committed to myogenic differentiation. Low Scrib expression is associated with the proliferative state and preventing self-renewal, whereas high Scrib levels reduce satellite cell proliferation. Satellite-cell-specific knockout of Scrib in mice causes a drastic and insurmountable defect in muscle regeneration. Thus, Scrib is a regulator of tissue stem cells, controlling population expansion and self-renewal with Scrib expression dynamics directing satellite cell fate.

  7. Heterogeneity in proliferative potential of ovine mesenchymal stem cell colonies.

    Science.gov (United States)

    Rhodes, N P; Srivastava, J K; Smith, R F; Longinotti, C

    2004-04-01

    Bone marrow biopsies were taken from the iliac crest of 28 individual sheep from three different breeds, ranging in age from 4 months to 8 years and mesenchymal stem cells (MSCs) isolated using selection due to plastic adherence. Cells were cultured in medium that had been selected for its effect on observed MSC proliferation, until populations of greater than 50 million had been obtained from each biopsy. The identity of the isolated cell populations as progenitors of the mesenchymal lineage was verified by deriving both osteoblastic and chondrocytic phenotypes when cultured in osteogenic and chondrogenic medium supplements, respectively. The rate of cell proliferation for each marrow biopsy was measured at each passage and the number of initial stem cells in each sample estimated. There was no statistically significant correlation between the age of the sheep and MSC proliferative potential, or age and estimated initial MSC number. There was no apparent significant difference between proliferation rate and sheep breed and colonies established from frozen cells grew at similar rates to pre-frozen cells. Counter intuitively, there appeared to be a negatively correlated trend between proliferation rate and MSC concentration in the samples. It is concluded that no initial descriptive statistics of the marrow biopsies can assist in estimating the proliferative potential, and therefore the timing of future surgeries, of MSCs sampled for the purposes of tissue engineering. PMID:15332606

  8. Anti-proliferative effect of Ficus pumila Linn. on human leukemic cell lines

    Directory of Open Access Journals (Sweden)

    Christopher Larbie

    2015-04-01

    Conclusion: These findings suggest that crude extracts of FPS and FPL have anti-proliferative effect on the leukemia cells. The antioxidant properties of the plant including phenolics may be partly responsible for the anti-proliferative activity. Further studies are required to isolate chemical components of the plant and establish their anti-proliferative activities and mechanism of action. [Int J Basic Clin Pharmacol 2015; 4(2.000: 330-336

  9. Glucocorticoid dose determines osteocyte cell fate

    OpenAIRE

    Jia, Junjing; Yao, Wei; Guan, Min; Dai, WeiWei; Shahnazari, Mohammad; Kar, Rekha; Bonewald, Lynda; Jiang, Jean X.; Lane, Nancy E.

    2011-01-01

    In response to cellular insult, several pathways can be activated, including necrosis, apoptosis, and autophagy. Because glucocorticoids (GCs) have been shown to induce both osteocyte apoptosis and autophagy, we sought to determine whether osteocyte cell fate in the presence of GCs was dose dependent by performing in vivo and in vitro studies. Male Swiss-Webster mice were treated with slow-release prednisolone pellets at 1.4, 2.8, and 5.6 mg/kg/d for 28 d. An osteocyte cell line, MLO-Y4 cells...

  10. The C. elegans TPR Containing Protein, TRD-1, Regulates Cell Fate Choice in the Developing Germ Line and Epidermis.

    Directory of Open Access Journals (Sweden)

    Samantha Hughes

    Full Text Available Correct cell fate choice is crucial in development. In post-embryonic development of the hermaphroditic Caenorhabitis elegans, distinct cell fates must be adopted in two diverse tissues. In the germline, stem cells adopt one of three possible fates: mitotic cell cycle, or gamete formation via meiosis, producing either sperm or oocytes. In the epidermis, the stem cell-like seam cells divide asymmetrically, with the daughters taking on either a proliferative (seam or differentiated (hypodermal or neuronal fate. We have isolated a novel conserved C. elegans tetratricopeptide repeat containing protein, TRD-1, which is essential for cell fate determination in both the germline and the developing epidermis and has homologs in other species, including humans (TTC27. We show that trd-1(RNAi and mutant animals have fewer seam cells as a result of inappropriate differentiation towards the hypodermal fate. In the germline, trd-1 RNAi results in a strong masculinization phenotype, as well as defects in the mitosis to meiosis switch. Our data suggests that trd-1 acts downstream of tra-2 but upstream of fem-3 in the germline sex determination pathway, and exhibits a constellation of phenotypes in common with other Mog (masculinization of germline mutants. Thus, trd-1 is a new player in both the somatic and germline cell fate determination machinery, suggestive of a novel molecular connection between the development of these two diverse tissues.

  11. Cell fate regulation in early mammalian development

    Science.gov (United States)

    Oron, Efrat; Ivanova, Natalia

    2012-08-01

    Preimplantation development in mammals encompasses a period from fertilization to implantation and results in formation of a blastocyst composed of three distinct cell lineages: epiblast, trophectoderm and primitive endoderm. The epiblast gives rise to the organism, while the trophectoderm and the primitive endoderm contribute to extraembryonic tissues that support embryo development after implantation. In many vertebrates, such as frog or fish, maternally supplied lineage determinants are partitioned within the egg. Cell cleavage that follows fertilization results in polarization of these factors between the individual blastomeres, which become restricted in their developmental fate. In contrast, the mouse oocyte and zygote lack clear polarity and, until the eight-cell stage, individual blastomeres retain the potential to form all lineages. How are cell lineages specified in the absence of a maternally supplied blueprint? This is a fundamental question in the field of developmental biology. The answer to this question lies in understanding the cell-cell interactions and gene networks involved in embryonic development prior to implantation and using this knowledge to create testable models of the developmental processes that govern cell fates. We provide an overview of classic and contemporary models of early lineage development in the mouse and discuss the emerging body of work that highlights similarities and differences between blastocyst development in the mouse and other mammalian species.

  12. Cell fate regulation in early mammalian development

    International Nuclear Information System (INIS)

    Preimplantation development in mammals encompasses a period from fertilization to implantation and results in formation of a blastocyst composed of three distinct cell lineages: epiblast, trophectoderm and primitive endoderm. The epiblast gives rise to the organism, while the trophectoderm and the primitive endoderm contribute to extraembryonic tissues that support embryo development after implantation. In many vertebrates, such as frog or fish, maternally supplied lineage determinants are partitioned within the egg. Cell cleavage that follows fertilization results in polarization of these factors between the individual blastomeres, which become restricted in their developmental fate. In contrast, the mouse oocyte and zygote lack clear polarity and, until the eight-cell stage, individual blastomeres retain the potential to form all lineages. How are cell lineages specified in the absence of a maternally supplied blueprint? This is a fundamental question in the field of developmental biology. The answer to this question lies in understanding the cell–cell interactions and gene networks involved in embryonic development prior to implantation and using this knowledge to create testable models of the developmental processes that govern cell fates. We provide an overview of classic and contemporary models of early lineage development in the mouse and discuss the emerging body of work that highlights similarities and differences between blastocyst development in the mouse and other mammalian species. (paper)

  13. Fibronectin mediates mesendodermal cell fate decisions

    Science.gov (United States)

    Cheng, Paul; Andersen, Peter; Hassel, David; Kaynak, Bogac L.; Limphong, Pattraranee; Juergensen, Lonny; Kwon, Chulan; Srivastava, Deepak

    2013-01-01

    Non-cell-autonomous signals often play crucial roles in cell fate decisions during animal development. Reciprocal signaling between endoderm and mesoderm is vital for embryonic development, yet the key signals and mechanisms remain unclear. Here, we show that endodermal cells efficiently promote the emergence of mesodermal cells in the neighboring population through signals containing an essential short-range component. The endoderm-mesoderm interaction promoted precardiac mesoderm formation in mouse embryonic stem cells and involved endodermal production of fibronectin. In vivo, fibronectin deficiency resulted in a dramatic reduction of mesoderm accompanied by endodermal expansion in zebrafish embryos. This event was mediated by regulation of Wnt signaling in mesodermal cells through activation of integrin-β1. Our findings highlight the importance of the extracellular matrix in mediating short-range signals and reveal a novel function of endoderm, involving fibronectin and its downstream signaling cascades, in promoting the emergence of mesoderm. PMID:23715551

  14. The "occlusis" model of cell fate restriction.

    Science.gov (United States)

    Lahn, Bruce T

    2011-01-01

    A simple model, termed "occlusis", is presented here to account for both cell fate restriction during somatic development and reestablishment of pluripotency during reproduction. The model makes three assertions: (1) A gene's transcriptional potential can assume one of two states: the "competent" state, wherein the gene is responsive to, and can be activated by, trans-acting factors in the cellular milieu, and the "occluded" state, wherein the gene is blocked by cis-acting, chromatin-based mechanisms from responding to trans-acting factors such that it remains silent irrespective of whether transcriptional activators are present in the milieu. (2) As differentiation proceeds in somatic lineages, lineage-inappropriate genes shift progressively and irreversibly from competent to occluded state, thereby leading to the restriction of cell fate. (3) During reproduction, global deocclusion takes place in the germline and/or early zygotic cells to reset the genome to the competent state in order to facilitate a new round of organismal development. PMID:20954221

  15. Primary stimulation by dendritic cells induces antiviral proliferative and cytotoxic T cell responses in vitro

    OpenAIRE

    1989-01-01

    We used well-gassed hanging drop (20 microliters) cultures with high concentrations of purified T cells from normal BALB/c mice to examine whether dendritic cells (DC) can induce primary antiviral proliferative T cell responses and generate virus-specific CTL. We found that DC exposed to infectious influenza virus in vitro or in vivo in small numbers (0.1-1%) resulted in strong proliferation of responder T cells within 3 d, and this was strongly inhibited by antibodies to class II MHC molecul...

  16. Tissue-specific targeting of cell fate regulatory genes by E2f factors.

    Science.gov (United States)

    Julian, L M; Liu, Y; Pakenham, C A; Dugal-Tessier, D; Ruzhynsky, V; Bae, S; Tsai, S-Y; Leone, G; Slack, R S; Blais, A

    2016-04-01

    Cell cycle proteins are important regulators of diverse cell fate decisions, and in this capacity have pivotal roles in neurogenesis and brain development. The mechanisms by which cell cycle regulation is integrated with cell fate control in the brain and other tissues are poorly understood, and an outstanding question is whether the cell cycle machinery regulates fate decisions directly or instead as a secondary consequence of proliferative control. Identification of the genes targeted by E2 promoter binding factor (E2f) transcription factors, effectors of the pRb/E2f cell cycle pathway, will provide essential insights into these mechanisms. We identified the promoter regions bound by three neurogenic E2f factors in neural precursor cells in a genome-wide manner. Through bioinformatic analyses and integration of published genomic data sets we uncovered hundreds of transcriptionally active E2f-bound promoters corresponding to genes that control cell fate processes, including key transcriptional regulators and members of the Notch, fibroblast growth factor, Wnt and Tgf-β signaling pathways. We also demonstrate a striking enrichment of the CCCTC binding factor transcription factor (Ctcf) at E2f3-bound nervous system-related genes, suggesting a potential regulatory co-factor for E2f3 in controlling differentiation. Finally, we provide the first demonstration of extensive tissue specificity among E2f target genes in mammalian cells, whereby E2f3 promoter binding is well conserved between neural and muscle precursors at genes associated with cell cycle processes, but is tissue-specific at differentiation-associated genes. Our findings implicate the cell cycle pathway as a widespread regulator of cell fate genes, and suggest that E2f3 proteins control cell type-specific differentiation programs by regulating unique sets of target genes. This work significantly enhances our understanding of how the cell cycle machinery impacts cell fate and differentiation, and will

  17. EMT and MET as paradigms for cell fate switching

    Institute of Scientific and Technical Information of China (English)

    Jiekai Chen; Qingkai Han; Duanqing Pei

    2012-01-01

    Cell fate determination is a major unsolved problem in cell and developmental biology,The discovery of reprogramming by pluripotent factors offers a rational system to investigate the molecular mechanisms associated with cell fate decisions.The idea that reprogramming of fibroblasts starts with a mesenchymal-epithelial transition (MET) suggests that the process is perhaps a reversal of epithelial to mesenchymal transition (EMT) found frequently during early embryogenesis,As such,we believe that investigations into MET-EMT may yield detailed molecular insights into cell fate decisions,not only for the switching between epithelial and mesenchymal cells,but also other cell types.

  18. Tristetraprolin mediates the anti-proliferative effects of metformin in breast cancer cells

    OpenAIRE

    Pandiri, Indira; Chen, Yingqing; Joe, Yeonsoo; Kim, Hyo Jeong; Park, Jeongmin; Chung, Hun Taeg; Park, Jeong Woo

    2016-01-01

    Metformin, which is a drug commonly prescribed to treat type 2 diabetes, has anti-proliferative effects in cancer cells; however, the molecular mechanisms underlying this effect remain largely unknown. The aim is to investigate the role of tristetraprolin (TTP), an AU-rich element-binding protein, in anti-proliferative effects of metformin in cancer cells. p53 wild-type and p53 mutant breast cancer cells were treated with metformin, and expression of TTP and c-Myc was analyzed by semi-quantit...

  19. Integrative modelling of the influence of MAPK network on cancer cell fate decision.

    Directory of Open Access Journals (Sweden)

    Luca Grieco

    2013-10-01

    Full Text Available The Mitogen-Activated Protein Kinase (MAPK network consists of tightly interconnected signalling pathways involved in diverse cellular processes, such as cell cycle, survival, apoptosis and differentiation. Although several studies reported the involvement of these signalling cascades in cancer deregulations, the precise mechanisms underlying their influence on the balance between cell proliferation and cell death (cell fate decision in pathological circumstances remain elusive. Based on an extensive analysis of published data, we have built a comprehensive and generic reaction map for the MAPK signalling network, using CellDesigner software. In order to explore the MAPK responses to different stimuli and better understand their contributions to cell fate decision, we have considered the most crucial components and interactions and encoded them into a logical model, using the software GINsim. Our logical model analysis particularly focuses on urinary bladder cancer, where MAPK network deregulations have often been associated with specific phenotypes. To cope with the combinatorial explosion of the number of states, we have applied novel algorithms for model reduction and for the compression of state transition graphs, both implemented into the software GINsim. The results of systematic simulations for different signal combinations and network perturbations were found globally coherent with published data. In silico experiments further enabled us to delineate the roles of specific components, cross-talks and regulatory feedbacks in cell fate decision. Finally, tentative proliferative or anti-proliferative mechanisms can be connected with established bladder cancer deregulations, namely Epidermal Growth Factor Receptor (EGFR over-expression and Fibroblast Growth Factor Receptor 3 (FGFR3 activating mutations.

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

    Directory of Open Access Journals (Sweden)

    Solyanik G. I.

    2010-04-01

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

  1. Inhibitors of glycoprotein processing alter T-cell proliferative responses to antigen and to interleukin 2.

    OpenAIRE

    Wall, K A; Pierce, J D; Elbein, A D

    1988-01-01

    Most of the cell-surface molecules involved in T-cell immune responses are N-linked glycoproteins. We have investigated the effects of inhibitors of glycoprotein processing on specific T-cell functions, with the dual aims of examining the functional role of carbohydrate and of testing the usefulness of such compounds as immunomodulators. Treatment of a cloned murine helper T-cell line with these inhibitors differentially affects the proliferative response of the cell, depending upon the natur...

  2. Proliferating cell nuclear antigen in neutrophil fate.

    Science.gov (United States)

    Witko-Sarsat, Véronique; Ohayon, Delphine

    2016-09-01

    The life span of a neutrophil is a tightly regulated process as extended survival is beneficial for pathogen elimination and cell death necessary to prevent cytotoxic content release from activated neutrophils at the inflammatory site. Therefore, the control between survival and death must be a dynamic process. We have previously described that proliferating cell nuclear antigen (PCNA) which is known as a nuclear protein pivotal in DNA synthesis, is a key element in controlling neutrophil survival through its association with procaspases. Contrary to the dogma which asserted that PCNA has a strictly nuclear function, in mature neutrophils, PCNA is present exclusively within the cytosol due to its nuclear export at the end of the granulocytic differentiation. More recent studies are consistent with the notion that the cytosolic scaffold of PCNA is aimed at modulating neutrophil fate rather than simply preventing death. Ultimately, targeting neutrophil survival might have important applications not just in the field of immunology and inflammation, but also in hematology and transfusion. The neutrophil emerges as a unique and powerful cellular model to unravel the basic mechanisms governing the cell cycle-independent functions of PCNA and should be considered as a leader of the pack. PMID:27558345

  3. Cell fate control in the developing central nervous system

    International Nuclear Information System (INIS)

    The principal neural cell types forming the mature central nervous system (CNS) are now understood to be diverse. This cellular subtype diversity originates to a large extent from the specification of the earlier proliferating progenitor populations during development. Here, we review the processes governing the differentiation of a common neuroepithelial cell progenitor pool into mature neurons, astrocytes, oligodendrocytes, ependymal cells and adult stem cells. We focus on studies performed in mice and involving two distinct CNS structures: the spinal cord and the cerebral cortex. Understanding the origin, specification and developmental regulators of neural cells will ultimately impact comprehension and treatments of neurological disorders and diseases. - Highlights: • Similar mechanisms regulate cell fate in different CNS cell types and structures. • Cell fate regulators operate in a spatial–temporal manner. • Different neural cell types rely on the generation of a diversity of progenitor cells. • Cell fate decision is dictated by the integration of intrinsic and extrinsic signals

  4. Cell fate control in the developing central nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Guérout, Nicolas; Li, Xiaofei; Barnabé-Heider, Fanie, E-mail: Fanie.Barnabe-Heider@ki.se

    2014-02-01

    The principal neural cell types forming the mature central nervous system (CNS) are now understood to be diverse. This cellular subtype diversity originates to a large extent from the specification of the earlier proliferating progenitor populations during development. Here, we review the processes governing the differentiation of a common neuroepithelial cell progenitor pool into mature neurons, astrocytes, oligodendrocytes, ependymal cells and adult stem cells. We focus on studies performed in mice and involving two distinct CNS structures: the spinal cord and the cerebral cortex. Understanding the origin, specification and developmental regulators of neural cells will ultimately impact comprehension and treatments of neurological disorders and diseases. - Highlights: • Similar mechanisms regulate cell fate in different CNS cell types and structures. • Cell fate regulators operate in a spatial–temporal manner. • Different neural cell types rely on the generation of a diversity of progenitor cells. • Cell fate decision is dictated by the integration of intrinsic and extrinsic signals.

  5. Proliferative activity, DNA synthesis and reproductive death of near and distant descendants of irradiated cells

    International Nuclear Information System (INIS)

    In experiments on HeLa cells a study was made of a change in the rate of DNA synthesis, proliferative activity and reproductive death of exposed cells and their descendants throughout a number of generations. The rate of DNA synthesis decreased in 4 postirradiation generations, and a maximum inhibition (by 50%) was registered 48 h following irradiation. The proliferative activity of the irradiated cell descendants markedly decreased throughout 18-20 generations resulting in an increased death rate and a loss of cells from a generation. It is suggested that even the distant desendants (18-20 generations) of expose cells exhibited some lesions which may, in time, become fatal events leading to cell death

  6. Oct4 shuffles Sox partners to direct cell fate

    OpenAIRE

    AlFatah Mansour, Abed; Hanna, Jacob H.

    2013-01-01

    Early cell fate decisions demand rapid rewiring of transcriptional circuits. Stanton and colleagues report on enhancer-dependent partnering of Oct4 with either Sox2 or Sox17 to switch from pluripotency to differentiation.

  7. Control of stem cell fate by engineering their micro andnanoenvironment

    Institute of Scientific and Technical Information of China (English)

    Michelle F Griffin; Peter E Butler; Alexander M Seifalian; Deepak M Kalaskar

    2015-01-01

    Stem cells are capable of long-term self-renewal anddifferentiation into specialised cell types, making theman ideal candidate for a cell source for regenerativemedicine. The control of stem cell fate has become amajor area of interest in the field of regenerative medicineand therapeutic intervention. Conventional methodsof chemically inducing stem cells into specific lineagesis being challenged by the advances in biomaterialtechnology, with evidence highlighting that materialproperties are capable of driving stem cell fate. Materialsare being designed to mimic the clues stem cells receivein their in vivo stem cell niche including topographicaland chemical instructions. Nanotopographical clues thatmimic the extracellular matrix (ECM) in vivo have shownto regulate stem cell differentiation. The delivery of ECMcomponents on biomaterials in the form of short peptidessequences has also proved successful in directing stem celllineage. Growth factors responsible for controlling stemcell fate in vivo have also been delivered via biomaterialsto provide clues to determine stem cell differentiation. Analternative approach to guide stem cells fate is to providegenetic clues including delivering DNA plasmids andsmall interfering RNAs via scaffolds. This review, aims toprovide an overview of the topographical, chemical andmolecular clues that biomaterials can provide to guidestem cell fate. The promising features and challenges ofsuch approaches will be highlighted, to provide directionsfor future advancements in this exciting area of stem celltranslation for regenerative medicine.

  8. Spontaneous and mitogen-induced proliferative activity of mononuclear cells in patients with pollinosis

    International Nuclear Information System (INIS)

    The induction of the proliferative response of B cells by lipopolysaccharide (LPS) and the proliferative activity of T lymphocytes during stimulation by phytohemagglutinin (PHA) in patients with pollinosis, with hypersensitivity to timothy-grass pollen, were studied. Peripheral blood mononuclear cells (MNC) from 17 patients with pollinosis aged from 16 to 40 years, were used. Lymphocytes (MNC) were isolated form heparinized blood by centrifugation and LPS from E. coli serotype 026:B6 in final concentrations was used as B-cell activator. Tritium-thymidine was added 18 h before the end of the culture time. Incorporated radioactivity was counted in a Mark III liquid scintillation beta-counter. The hyperproduction of IgE observed in atopic patients is more likely to be connected with changes in the later stages of differentiation of IgE-synthesizing B-lymphocytes (at the memory cell level) into IgE-producing plasma cells

  9. Spontaneous and mitogen-induced proliferative activity of mononuclear cells in patients with pollinosis

    Energy Technology Data Exchange (ETDEWEB)

    Serov, A.A.

    1985-06-01

    The induction of the proliferative response of B cells by lipopolysaccharide (LPS) and the proliferative activity of T lymphocytes during stimulation by phytohemagglutinin (PHA) in patients with pollinosis, with hypersensitivity to timothy-grass pollen, were studied. Peripheral blood mononuclear cells (MNC) from 17 patients with pollinosis aged from 16 to 40 years, were used. Lymphocytes (MNC) were isolated form heparinized blood by centrifugation and LPS from E. coli serotype 026:B6 in final concentrations was used as B-cell activator. Tritium-thymidine was added 18 h before the end of the culture time. Incorporated radioactivity was counted in a Mark III liquid scintillation beta-counter. The hyperproduction of IgE observed in atopic patients is more likely to be connected with changes in the later stages of differentiation of IgE-synthesizing B-lymphocytes (at the memory cell level) into IgE-producing plasma cells.

  10. Tristetraprolin mediates the anti-proliferative effects of metformin in breast cancer cells.

    Science.gov (United States)

    Pandiri, Indira; Chen, Yingqing; Joe, Yeonsoo; Kim, Hyo Jeong; Park, Jeongmin; Chung, Hun Taeg; Park, Jeong Woo

    2016-02-01

    Metformin, which is a drug commonly prescribed to treat type 2 diabetes, has anti-proliferative effects in cancer cells; however, the molecular mechanisms underlying this effect remain largely unknown. The aim is to investigate the role of tristetraprolin (TTP), an AU-rich element-binding protein, in anti-proliferative effects of metformin in cancer cells. p53 wild-type and p53 mutant breast cancer cells were treated with metformin, and expression of TTP and c-Myc was analyzed by semi-quantitative RT-PCR, Western blots, and promoter activity assay. Breast cancer cells were transfected with siRNA against TTP to inhibit TTP expression or c-Myc and, after metformin treatment, analyzed for cell proliferation by MTS assay. Metformin induces the expression of tristetraprolin (TTP) in breast cancer cells in a p53-independent manner. Importantly, inhibition of TTP abrogated the anti-proliferation effect of metformin. We observed that metformin decreased c-Myc levels, and ectopic expression of c-Myc blocked the effect of metformin on TTP expression and cell proliferation. Our data indicate that metformin induces TTP expression by reducing the expression of c-Myc, suggesting a new model whereby TTP acts as a mediator of metformin's anti-proliferative activity in cancer cells. PMID:26956973

  11. The influence of immunosuppressive drugs on neural stem/progenitor cell fate in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Skardelly, Marco, E-mail: Marco.Skardelly@med.uni-tuebingen.de [Department of Neurosurgery, University Hospital, Leipzig (Germany); Translational Centre for Regenerative Medicine, University of Leipzig, Leipzig (Germany); Glien, Anja; Groba, Claudia; Schlichting, Nadine [Department of Neurosurgery, University Hospital, Leipzig (Germany); Kamprad, Manja [Institute of Clinical Immunology, Medical Faculty, University of Leipzig, Leipzig (Germany); Meixensberger, Juergen [Department of Neurosurgery, University Hospital, Leipzig (Germany); Milosevic, Javorina [Translational Centre for Regenerative Medicine, University of Leipzig, Leipzig (Germany)

    2013-12-10

    In allogenic and xenogenic transplantation, adequate immunosuppression plays a major role in graft survival, especially over the long term. The effect of immunosuppressive drugs on neural stem/progenitor cell fate has not been sufficiently explored. The focus of this study is to systematically investigate the effects of the following four different immunotherapeutic strategies on human neural progenitor cell survival/death, proliferation, metabolic activity, differentiation and migration in vitro: (1) cyclosporine A (CsA), a calcineurin inhibitor; (2) everolimus (RAD001), an mTOR-inhibitor; (3) mycophenolic acid (MPA, mycophenolate), an inhibitor of inosine monophosphate dehydrogenase and (4) prednisolone, a steroid. At the minimum effective concentration (MEC), we found a prominent decrease in hNPCs' proliferative capacity (BrdU incorporation), especially for CsA and MPA, and an alteration of the NAD(P)H-dependent metabolic activity. Cell death rate, neurogenesis, gliogenesis and cell migration remained mostly unaffected under these conditions for all four immunosuppressants, except for apoptotic cell death, which was significantly increased by MPA treatment. - Highlights: • Four immunosuppresants (ISs) were tested in human neural progenitor cells in vitro. • Cyclosporine A and mycophenolic acid showed a prominent anti-proliferative activity • Mycophenolic acid exhibited a significant pro-apoptotic effect. • NAD(P)H-dependent metabolic activity was occasionally induced by ISs. • Neuronal differentiation and migration potential remained unaffected by ISs treatment.

  12. The influence of immunosuppressive drugs on neural stem/progenitor cell fate in vitro

    International Nuclear Information System (INIS)

    In allogenic and xenogenic transplantation, adequate immunosuppression plays a major role in graft survival, especially over the long term. The effect of immunosuppressive drugs on neural stem/progenitor cell fate has not been sufficiently explored. The focus of this study is to systematically investigate the effects of the following four different immunotherapeutic strategies on human neural progenitor cell survival/death, proliferation, metabolic activity, differentiation and migration in vitro: (1) cyclosporine A (CsA), a calcineurin inhibitor; (2) everolimus (RAD001), an mTOR-inhibitor; (3) mycophenolic acid (MPA, mycophenolate), an inhibitor of inosine monophosphate dehydrogenase and (4) prednisolone, a steroid. At the minimum effective concentration (MEC), we found a prominent decrease in hNPCs' proliferative capacity (BrdU incorporation), especially for CsA and MPA, and an alteration of the NAD(P)H-dependent metabolic activity. Cell death rate, neurogenesis, gliogenesis and cell migration remained mostly unaffected under these conditions for all four immunosuppressants, except for apoptotic cell death, which was significantly increased by MPA treatment. - Highlights: • Four immunosuppresants (ISs) were tested in human neural progenitor cells in vitro. • Cyclosporine A and mycophenolic acid showed a prominent anti-proliferative activity • Mycophenolic acid exhibited a significant pro-apoptotic effect. • NAD(P)H-dependent metabolic activity was occasionally induced by ISs. • Neuronal differentiation and migration potential remained unaffected by ISs treatment

  13. Proliferative responses to canine thyroglobulin of peripheral blood mononuclear cells from hypothyroid dogs.

    Science.gov (United States)

    Tani, Hiroyuki; Nabetani, Tomoyo; Sasai, Kazumi; Baba, Eiichiroh

    2005-04-01

    The immune responses of hypothyroid dogs to canine thyroglobulin (cTg) were evaluated for the proliferative ability of peripheral blood mononuclear cells (PBMC). PBMC from three hypothyroid dogs with high titers of thyroglobulin autoantibody (TgAA) and 3 clinically normal dogs were cultured with 5, 10, or 20 microg/ml of cTg for 72 hr. The proliferative responses of the cells were determined by the level of incorporated BrdU. The numbers of cells expressing Thy-1, CD4, CD8 and IgG in the PBMC were counted by the immunofluorescence method. Proliferative responses to cTg were observed in the cells from hypothyroid dogs. The number of cells expressing IgG and CD8 in the hypothyroid dogs tended to be high compared with the clinically normal dogs. The CD4+ cells in cultures from hypothyroid dogs increased depending upon the amount of cTg. There was a significant (Pdogs. These findings suggest a possible relationship between canine hypothyroidism and cellular immunity. Loss of self tolerance to thyroid antigens in CD4+ T cells may play an important role in the development of canine hypothyroidism. PMID:15876785

  14. Metformin Enhances Anti-proliferative Effect of Cisplatin in Cervical Cancer Cell Line

    OpenAIRE

    Ratih D. Yudhani; Riza N. Pesik; Dono Indarto

    2016-01-01

    Cervival cancer is one of the top rank of gynecological malignancy in the world, leading to high morbidity and mortality rates. Cisplatin is a chemotherapeutic agent that is generally used to treat cervical cancer but the use of this drug is limited because of serious side effects. Metformin, a diabetic drug, decreases not only blood glucose levels but also cell viability of some cancer cells. The aim of this study was to investigate the anti-proliferative effect of combination metformin and ...

  15. ROLE OF THE MORPHOMETRIC PARAMETERS OF INTRATUMORAL MICROVESSELS AND THE PROLIFERATIVE ACTIVITY OF TUMOR CELLS IN RENAL CELL CARCINOMA

    Directory of Open Access Journals (Sweden)

    N. A. Gorban

    2014-08-01

    Full Text Available Tumor cell proliferation and angiogenesis are essential factors for tumor growth, progression, and metastasis.Objective: to assess the relationship between the values of proliferative activity and the morphometric parameters of intratumoral microvessels in metastatic and localized carcinomas of the kidney.Materials and methods. Surgical specimens taken from 54 patients (32 men and 22 women aged 26 to 69 years (mean age 55 ± 1.5 years with the verified diagnosis of clear-cell renal cell carcinoma (RCC were studied.Conclusion. Proliferative activity and angioarchitectonics are an important biological characteristic of a tumor of unequal clinical value in RCC. Metastatic carcinoma has a higher proliferative activity and a low tumor vascularization than those of localized carcinoma.

  16. Human T cell responses to dengue virus antigens. Proliferative responses and interferon gamma production.

    OpenAIRE

    Kurane, I; Innis, B L; Nisalak, A; Hoke, C; Nimmannitya, S; Meager, A.; Ennis, F A

    1989-01-01

    The severe complications of dengue virus infections, hemorrhagic manifestations and shock, are more commonly observed during secondary dengue virus infections than during primary infections. It has been speculated that these complications are mediated by cross-reactive host-immune responses. We have begun to analyze human T cell responses to dengue antigens in vitro to explain the possible role of T lymphocytes in the pathogenesis of these complications. Dengue antigens induce proliferative r...

  17. Cdc6 is a rate-limiting factor for proliferative capacity during HL60 cell differentiation

    International Nuclear Information System (INIS)

    The DNA replication (or origin) licensing pathway represents a critical step in cell proliferation control downstream of growth signalling pathways. Repression of origin licensing through down-regulation of the MCM licensing factors (Mcm2-7) is emerging as a ubiquitous route for lowering proliferative capacity as metazoan cells exit the cell division cycle into quiescent, terminally differentiated and senescent 'out-of-cycle' states. Using the HL60 monocyte/macrophage differentiation model system and a cell-free DNA replication assay, we have undertaken direct biochemical investigations of the coupling of origin licensing to the differentiation process. Our data show that down-regulation of the MCM loading factor Cdc6 acts as a molecular switch that triggers loss of proliferative capacity during early engagement of the somatic differentiation programme. Consequently, addition of recombinant Cdc6 protein to in vitro replication reactions restores DNA replication competence in nuclei prepared from differentiating cells. Differentiating HL60 cells over-expressing either wild-type Cdc6 or a CDK phosphorylation-resistant Cdc6 mutant protein (Cdc6A4) exhibit an extended period of cell proliferation compared to mock-infected cells. Notably, differentiating HL60 cells over-expressing the Cdc6A4 mutant fail to down-regulate Cdc6 protein levels, suggesting that CDK phosphorylation of Cdc6 is linked to its down-regulation during differentiation and the concomitant decrease in cell proliferation. In this experimental model, Cdc6 therefore plays a key role in the sequential molecular events leading to repression of origin licensing and loss of proliferative capacity during execution of the differentiation programme

  18. Intravitreal Ranibizumab for Stage IV Proliferative Sickle Cell Retinopathy: A First Case Report

    Directory of Open Access Journals (Sweden)

    Panagiotis G. Mitropoulos

    2014-01-01

    Full Text Available Purpose. To present the case of a 27-year-old male patient with stage IV proliferative sickle cell retinopathy, treated with one intravitreal injection of ranibizumab, showing regression of the neovascularization and no recurrence at the 9-month follow-up. Methods. A 27-year-old male patient presented with blurred vision and floaters in the right eye since three days. His best corrected visual acuity was 6/18. Ophthalmological examination and fluorescein angiography revealed proliferative sickle cell retinopathy stage IV with vitreous hemorrhage and sea fan neovascularization, as well as ischemic areas at the temporal periphery. Results. The patient was treated with one intravitreal injection of ranibizumab, presenting improvement in the visual acuity from 6/18 to 6/6, resolution of vitreous hemorrhage, and regression of the neovascularization. Additionally, he underwent scatter laser photocoagulation at the ischemic areas. At the 9-month follow-up there was no recurrence, while no adverse effects were noticed. Conclusions. Intravitreal ranibizumab may be a useful adjunct to laser photocoagulation in the management of proliferative sickle cell retinopathy and may permit some patients to avoid pars plana vitrectomy for vitreous hemorrhage.

  19. Proliferative cell response to loosening of total hip replacements: a cytofluorographic cell cycle analysis.

    Science.gov (United States)

    Santavirta, S; Pajamäki, J; Eskola, A; Konttinen, Y T; Lindholm, T

    1991-01-01

    Monocyte/macrophages and fibroblasts are the major reactive cells in the periprosthetic connective tissue in a loose totally replaced hip. Monocyte/macrophages are bone-marrow-derived, hematogenous cells, whereas mesenchymal fibroblasts replenish by local proliferation. The cell-cycle-phase frequency distribution therefore reflects the local mitotic fibroblast response to the loose total hip replacement (THR) implant. In 13 patients who underwent revision of a loose THR implant, most of the local cells were in the resting G0/G1 phase (88.1 +/- 6.3%, mean +/- SD), whereas 8.6 +/- 3.7% were in the S phase of the cycle, and 3.4 +/- 2.9% had already reached the G2/M phase. The highest DNA values were recorded in an osteoarthritic patient undergoing revision 4 years after the primary uncemented THR, while the lowest values were observed in a rheumatoid arthritis patient with a loose cemented prosthesis 15 years after the primary operation. The results suggest that the local proliferative fibroblast response in general is uniform and does not seem to depend on the type of prosthesis or the use of cement. The responses in aggressive granulomatous-type loosening and the common type of loosening were similar. PMID:1772725

  20. Age related decline in the proliferative response of human T cells to OKT3 stimulation

    International Nuclear Information System (INIS)

    The level of the in vitro proliferative response of human peripheral blood mononuclear cells (PBMC) to the OKT3 monoclonal antibody is directly related to the level of monocyte representation in the cell population. The responses to OKT3 stimulation of PBMC obtained from different individual are difficult to interpret due to variable percentage representation of monocytes. To eliminate this problem purified T cells from humans of various ages were incubated with 2 ng/ml OKT3 antibody and 10% purified autologous monocytes. The 3H-TdR incorporation of 1 x 105 T cells at 72 hrs of culture was 69,939 +/- 6085 (SEM) cpm for young individuals (mean age 35 yrs) and 33,163 +/- 2962 cpm for healthy elderly individuals (mean age 78 yrs). In addition, IL2 receptors were measured using two color fluorescence and flow cytometry with phycoerythrin conjugated anti-IL2 receptor antibody and FITC conjugated OKT11 antibody. The percentage of cells expressing IL2 receptors was 46% for the cells from the young individuals and 23% for cells from old individuals. These results suggest that the age related decline in the proliferative ability of T cells is partially due to a decreased expression of IL2 receptors and that proliferation and IL2 receptor expression is under the control of monocyte accessory cells

  1. FY08 LDRD Final Report Stem Cell Fate Decisions

    Energy Technology Data Exchange (ETDEWEB)

    Hiddessen, A

    2009-03-02

    A detailed understanding of the biological control of fate decisions of stem and progenitor cells is needed to harness their full power for tissue repair and/or regeneration. Currently, internal and external factors that regulate stem cell fate are not fully understood. We aim to engineer biocompatible tools to facilitate the measurement and comparison of the roles and significance of immobilized factors such as extracellular matrix and signaling peptides, synergistic and opposing soluble factors and signals, and cell-to-cell communication, in stem cell fate decisions. Our approach is based on the development of cell microarrays to capture viable stem/progenitor cells individually or in small clusters onto substrate-bound signals (e.g. proteins), combined with conventional antibody and customized subcellular markers made in-house, to facilitate tracking of cell behavior during exposure to relevant signals. Below we describe our efforts, including methods to manipulate a model epithelial stem cell system using a custom subcellular reporter to track and measure cell signaling, arrays with surface chemistry that support viable cells and enable controlled presentation of immobilized signals to cells on the array and fluorescence-based measurement of cell response, and successful on-array tests via conventional immunofluorescence assays that indicate correct cell polarity, localization of junctional proteins, and phenotype, properties which are essential to measuring true cell responses.

  2. Cdc20 control of cell fate during prolonged mitotic arrest

    DEFF Research Database (Denmark)

    Nilsson, Jakob

    2011-01-01

    The fate of cells arrested in mitosis by antimitotic compounds is complex but is influenced by competition between pathways promoting cell death and pathways promoting mitotic exit. As components of both of these pathways are regulated by Cdc20-dependent degradation, I hypothesize that variations...

  3. Divergence of zebrafish and mouse lymphatic cell fate specification pathways

    DEFF Research Database (Denmark)

    van Impel, Andreas; Zhao, Zhonghua; Hermkens, Dorien M A;

    2014-01-01

    In mammals, the homeodomain transcription factor Prox1 acts as the central regulator of lymphatic cell fate. Its restricted expression in a subset of cardinal vein cells leads to a switch towards lymphatic specification and hence represents a prerequisite for the initiation of lymphangiogenesis. ...

  4. Binary cell fate decisions and fate transformation in the Drosophila larval eye.

    Directory of Open Access Journals (Sweden)

    Abhishek Kumar Mishra

    Full Text Available The functionality of sensory neurons is defined by the expression of specific sensory receptor genes. During the development of the Drosophila larval eye, photoreceptor neurons (PRs make a binary choice to express either the blue-sensitive Rhodopsin 5 (Rh5 or the green-sensitive Rhodopsin 6 (Rh6. Later during metamorphosis, ecdysone signaling induces a cell fate and sensory receptor switch: Rh5-PRs are re-programmed to express Rh6 and become the eyelet, a small group of extraretinal PRs involved in circadian entrainment. However, the genetic and molecular mechanisms of how the binary cell fate decisions are made and switched remain poorly understood. We show that interplay of two transcription factors Senseless (Sens and Hazy control cell fate decisions, terminal differentiation of the larval eye and its transformation into eyelet. During initial differentiation, a pulse of Sens expression in primary precursors regulates their differentiation into Rh5-PRs and repression of an alternative Rh6-cell fate. Later, during the transformation of the larval eye into the adult eyelet, Sens serves as an anti-apoptotic factor in Rh5-PRs, which helps in promoting survival of Rh5-PRs during metamorphosis and is subsequently required for Rh6 expression. Comparably, during PR differentiation Hazy functions in initiation and maintenance of rhodopsin expression. Hazy represses Sens specifically in the Rh6-PRs, allowing them to die during metamorphosis. Our findings show that the same transcription factors regulate diverse aspects of larval and adult PR development at different stages and in a context-dependent manner.

  5. Arctigenin in combination with quercetin synergistically enhances the anti-proliferative effect in prostate cancer cells

    Science.gov (United States)

    Wang, Piwen; Phan, Tien; Gordon, David; Chung, Seyung; Henning, Susanne M.; Vadgama, Jaydutt V.

    2014-01-01

    Scope We investigated whether a combination of two promising chemopreventive agents arctigenin and quercetin increases the anti-carcinogenic potency at lower concentrations than necessary when used individually in prostate cancer. Methods and results Androgen-dependent LAPC-4 and LNCaP prostate cancer cells were treated with low doses of arctigenin and quercetin alone or in combination for 48h. The anti-proliferative activity of arctigenin was 10-20 fold stronger than quercetin in both cell lines. Their combination synergistically enhanced the anti-proliferative effect, with a stronger effect in androgen receptor (AR) wild-type LAPC-4 cells than in AR mutated LNCaP cells. Arctigenin demonstrated a strong ability to inhibit AR protein expression in LAPC-4 cells. The combination treatment significantly inhibited both AR and PI3K/Akt pathways compared to control. A protein array analysis revealed that the mixture targets multiple pathways particularly in LAPC-4 cells including Stat3 pathway. The mixture significantly inhibited the expression of several oncogenic microRNAs including miR-21, miR-19b, and miR-148a compared to control. The mixture also enhanced the inhibition of cell migration in both cell lines compared to individual compounds tested. Conclusion The combination of arctigenin and quercetin, that target similar pathways, at low physiological doses, provides a novel regimen with enhanced chemoprevention in prostate cancer. PMID:25380086

  6. Effects of argon laser radiation on aortic endothelial cells: Early membrane changes and proliferative response

    International Nuclear Information System (INIS)

    Membrane fluidity, transmembrane signaling responses, and proliferative characteristics of endothelial cells were studied to characterize biochemical and molecular changes after treatment with argon laser energy. Bovine aortic endothelial cells grown in monolayers were irradiated at 50, 100, and 200 J with an argon laser (wavelength, 488 and 514 nm). Proliferation, assayed by [3H]thymidine incorporation, was measured daily for 6 days. An initial lag phase was observed for irradiated cells when compared to nonirradiated controls (P less than 0.03), with eventual recovery by the third day. Membrane fluidity, determined by fluorescence anisotropy, was measured 1 hr after irradiation. A decrease in static rotational motion of 1,6-diphenyl-1,3,5-hexatriene (DPH) was noted in irradiated versus nonirradiated cells indicating a decrease in membrane fluidity (P less than 0.02). Dynamic studies of intracellular calcium and pH flux utilizing fluorescent probes demonstrated a preserved response to mitogenic stimulation. An increase in intracellular Ca2+ with a concomitant alkalinization of the intracellular milieu was observed in irradiated and non-irradiated cells in response to stimulation with endothelial cell growth factor (ECGF). These responses resemble those characterized for other mitogens. Argon laser energy applied to aortic endothelial cells decreases membrane fluidity early after irradiation. These alterations probably cause the initial lag observed in their proliferative response; however, the capacity to respond to exogenous mitogenic stimulation is maintained

  7. Long-term nonprogression and broad HIV-1-specific proliferative T-cell responses

    Directory of Open Access Journals (Sweden)

    Nesrina eImami

    2013-03-01

    Full Text Available Complex mechanisms underlying the maintenance of fully functional, proliferative, HIV-1-specific T-cell responses involve processes from early T-cell development through to the final stages of T-cell differentiation and antigen recognition. Virus-specific proliferative CD4 and CD8 T-cell responses, important for the control of infection, are observed in some HIV-1+ patients during early stages of disease, and are maintained in long-term nonprogressing subjects. In the vast majority of HIV-1+ patients, full immune functionality is lost when proliferative HIV-1-specific T-cell responses undergo a variable progressive decline throughout the course of chronic infection. This appears irreparable despite administration of potent combination antiretroviral therapy, which to date is non-curative, necessitating life-long administration and the development of effective, novel, therapeutic interventions. While a sterilising cure, involving clearance of virus from the host, remains a primary aim, a functional cure may be a more feasible goal with considerable impact on worldwide HIV-1 infection. Such an approach would enable long-term co-existence of host and virus in the absence of toxic and costly drugs. Effective immune homeostasis coupled with a balanced response appropriately targeting conserved viral antigens, in a manner that avoids hyperactivation and exhaustion, may prove to be the strongest correlate of durable viral control. This review describes novel concepts underlying full immune functionality in the context of HIV-1 infection, which may be utilised in future strategies designed to improve upon existing therapy. The aim will be to induce long-term nonprogressor or elite controller status in every infected host, through immune-mediated control of viraemia and reduction of viral reservoirs, leading to lower HIV-1 transmission rates.

  8. Buformin exhibits anti-proliferative and anti-invasive effects in endometrial cancer cells

    Science.gov (United States)

    Kilgore, Joshua; Jackson, Amanda L; Clark, Leslie H; Guo, Hui; Zhang, Lu; Jones, Hannah M; Gilliam, Timothy P; Gehrig, Paola A; Zhou, Chunxiao; Bae-Jump, Victoria L

    2016-01-01

    Objective: Biguanides are anti-diabetic drugs that are thought to have anti-tumorigenic effects. Most pre-clinical studies have focused on metformin for cancer treatment and prevention; however, buformin may be potentially more potent than metformin. Given this, our goal was to evaluate the effects of buformin on cell growth, adhesion and invasion in endometrial cancer cell lines. Methods: The ECC-1 and Ishikawa endometrial cancer cell lines were used. Cell proliferation was assessed by MTT assay. Apoptosis and cell cycle analysis was performed by FITC Annexin V assay and propidium iodide staining, respectively. Adhesion was analyzed using the laminin adhesion assay. Invasion was assessed using the transwell invasion assay. The effects of buformin on the AMPK/mTOR pathway were determined by Western immunoblotting. Results: Buformin and metformin inhibited cell proliferation in a dose-dependent manner in both endometrial cancer cell lines. IC50s were 1.4-1.6 mM for metformin and 8-150 μM for buformin. Buformin induced cell cycle G1 phase arrest in the ECC-1 cells and G2 phase arrest in the Ishikawa cells. For both ECC-1 and Ishikawa cells, treatment with buformin resulted in induction of apoptosis, reduction in adhesion and invasion, activation of AMPK and inhibition of phosphorylated-S6. Buformin potentiated the anti-proliferative effects of paclitaxel in both cell lines. Conclusion: Buformin has significant anti-proliferative and anti-metastatic effects in endometrial cancer cells through modulation of the AMPK/mTOR pathway. IC50 values were lower for buformin than metformin, suggesting that buformin may be more potent for endometrial cancer treatment and worthy of further investigation. PMID:27398153

  9. Hepatic progenitor cell resistance to TGF-β1's proliferative and apoptotic effects

    International Nuclear Information System (INIS)

    The success of hepatocellular therapies using stem or progenitor cell populations is dependent upon multiple factors including the donor cell, microenvironment, and etiology of the liver injury. The following experiments investigated the impact of TGF-β1 on a previously described population of hepatic progenitor cells (HPC). The majority of the hepatic progenitor cells were resistant to endogenously produced TGF-β1's proapoptotic and anti-proliferative effects unlike more well-differentiated cellular populations (e.g., mature hepatocytes). Surprisingly, in vitro TGF-β1 supplementation significantly inhibited de novo hepatic progenitor cell colony formation possibly via an indirect mechanism(s). Therefore despite the HPC's direct resistance to supplemental TGF-β1, this cytokine's inhibitory effect on colony formation could have a potential negative impact on the use of these cells as a therapy for patients with liver disease

  10. Restoration of proliferative response to M. leprae antigens in lepromatous T cells against candidate antileprosy vaccines.

    Science.gov (United States)

    Mustafa, A S

    1996-09-01

    Several studies conducted in the last decade suggest that Mycobacterium lepraereactive T cells exist in lepromatous patients, but their number may be too few to yield a detectable response in cell-mediated immunity (CMI) assays. Immunizations with candidate antileprosy vaccines and stimulation of T cells with M. leprae + interleukin-2 restore the M. leprae-induced CMI response in lepromatous leprosy patients. These immunizations and stimulation may enrich the pre-existing M. leprae-responsive T cells in lepromatous patients and, thereby, induce a detectable CMI response to M. leprae antigens upon repeat testing. To verify this proposition, we carried out a study in a group of 10 lepromatous leprosy patients. Peripheral blood mononuclear cells (PBMC) obtained from these patients were anergic to M. leprae antigens in proliferative assays, but they responded to the antigens of candidate antileprosy vaccines, i.e., M. bovis BCG, M. bovis BCG + M. leprae, and Mycobacterium w. The enrichment of M. leprae-responsive T cells was performed by establishing T-cell lines from the PBMC after in vitro stimulation with M. leprae, M. bovis BCG, M. bovis BCG + M. leprae, and Mycobacterium w. When tested for their proliferative responses, 1/10, 3/10, 6/10 and 2/10 T-cell lines established against M. leprae, M. bovis BCG, M. bovis BCG + M. leprae, and Mycobacterium w, respectively, responded to M. leprae. These results suggest that enrichment of pre-existing M. leprae-responsive T cells may contribute to the restoration of the T-cell response to M. leprae in some lepromatous patients. Four of the 10 M. leprae-induced T-cell lines proliferated in response to the 65 kDa, 36 kDa, 28 kDa, and 12 kDa recombinant antigens of M. leprae, suggesting that the nonresponsiveness of T cells in some lepromatous patients may be overcome by using recombinant antigens of M. leprae. PMID:8862259

  11. An ECHO in biology II: Insights in chondrocyte cell fate

    NARCIS (Netherlands)

    Schivo, S.; Scholma, J.; Huang, X.; Zhong, L.; Pol, van de J.C.; Karperien, H.B.J.; Langerak, R.; Post, J.N.

    2016-01-01

    Purpose: An intricate network of regulatory processes determines the chondrocyte cell fate during development and maintains tissue homeostasis. In the event of a disease such as OA, the regulatory network is critically compromised. To cure the disease, we need to restore the regulatory processes to

  12. Chemicals as the Sole Transformers of Cell Fate

    Science.gov (United States)

    Ebrahimi, Behnam

    2016-01-01

    Forced expression of lineage-specific transcription factors in somatic cells can result in the generation of different cell types in a process named direct reprogramming, bypassing the pluripotent state. However, the introduction of transgenes limits the therapeutic applications of the produced cells. Numerous small-molecules have been introduced in the field of stem cell biology capable of governing self-renewal, reprogramming, transdifferentiation and regeneration. These chemical compounds are versatile tools for cell fate conversion toward desired outcomes. Cell fate conversion using small-molecules alone (chemical reprogramming) has superiority over arduous traditional genetic techniques in several aspects. For instance, rapid, transient, and reversible effects in activation and inhibition of functions of specific proteins are of the profits of small-molecules. They are cost-effective, have a long half-life, diversity on structure and function, and allow for temporal and flexible regulation of signaling pathways. Additionally, their effects could be adjusted by fine-tuning concentrations and combinations of different small-molecules. Therefore, chemicals are powerful tools in cell fate conversion and study of stem cell and chemical biology in vitro and in vivo. Moreover, transgene-free and chemical-only transdifferentiation approaches provide alternative strategies for the generation of various cell types, disease modeling, drug screening, and regenerative medicine. The current review gives an overview of the recent findings concerning transdifferentiation by only small-molecules without the use of transgenes. PMID:27426081

  13. Anti-proliferative activity of Fumaria vaillantii extracts on different cancer cell lines

    Directory of Open Access Journals (Sweden)

    Fatemeh Haji Abbas Tabrizi

    2016-01-01

    Full Text Available Plant-derived natural products are known to have cancer chemo-preventive and chemo-therapeutic properties. Plant extracts or their active constituents are used as folk medicine in traditional therapies by 80% of the world population. The aim of the present study was to determine the anti-proliferative potential of Fumaria vaillantii extracts on three different cancer cell lines including malignant melanoma SKMEL-3, human breast adenocarcinoma MCF-7 and human myelogenous leukemia K562 as well as human gingival fibroblast (HGF as normal cell line. Anti-proliferative activity was evaluated by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT, flowcytometry and annexin methods. Total phenolics and flavonoids were determined by Folin-Ciocalteu and aluminum chloride methods. Chloroform fraction had the lowest IC 50 value at 72 h (0.1 μg/ml in MCF-7 cells. Flowcytometry and annexin-V analysis indicated that the chloroform fraction induced necrosis in MCF-7 cells. In addition, the colorimetric methods showed that the methanolic fraction possessed the highest amount of total phenolics (33.03 ± 0.75 mg/g of dry powder and flavonoids (10.5 ± 2.0 mg/g of dry powder.The collective data demonstrated that F. vaillantii chloroform fraction may contain effective compounds with chemo-therapeutic potential act through an apoptotic independent pathway.

  14. White kidney bean lectin exerts anti-proliferative and apoptotic effects on cancer cells.

    Science.gov (United States)

    Chan, Yau Sang; Xia, Lixin; Ng, Tzi Bun

    2016-04-01

    A 60-kDa glucosamine binding lectin, white kidney bean lectin (WKBL), was purified from Phaseolus vulgaris cv. white kidney beans, by application of anion exchange chromatography on Q-Sepharose, affinity chromatography on Affi-gel blue gel, and FPLC-size exclusion on Superdex 75. The anti-proliferative activity of WKBL on HONE1 cells and HepG2 cells was stronger than the activity on MCF7 cells and WRL68 cells (IC50 values for a 48-h treatment with WKBL on HONE1 cells: 18.8μM; HepG2 cells: 19.7μM; MCF7 cells: 26.9μM; and WRL68 cells: >80μM). The activity could be reduced by addition of glucosamine, which occupies the binding sites of WKBL, indicating that carbohydrate binding is crucial for the activity. Annexin V-FITC and PI staining, JC-1 staining and Hoechst 33342 staining revealed that apoptosis was induced on WKBL-treated HONE1 cells and HepG2 cells, but not as obviously on MCF7 cells. Cell cycle analysis also showed a slight cell cycle arrest on HONE1 cells after WKBL treatment. Western blotting suggested that WKBL induced apoptosis of HONE1 cells occurred through the extrinsic apoptosis pathway, with detection of increased level of active caspase 3, 8 and 9. PMID:26769089

  15. Cranberry and Grape Seed Extracts Inhibit the Proliferative Phenotype of Oral Squamous Cell Carcinomas

    Directory of Open Access Journals (Sweden)

    Kourt Chatelain

    2011-01-01

    Full Text Available Proanthocyanidins, compounds highly concentrated in dietary fruits, such as cranberries and grapes, demonstrate significant cancer prevention potential against many types of cancer. The objective of this study was to evaluate cranberry and grape seed extracts to quantitate and compare their anti-proliferative effects on the most common type of oral cancer, oral squamous cell carcinoma. Using two well-characterized oral squamous cell carcinoma cell lines, CAL27 and SCC25, assays were performed to evaluate the effects of cranberry and grape seed extract on phenotypic behaviors of these oral cancers. The proliferation of both oral cancer cell lines was significantly inhibited by the administration of cranberry and grape seed extracts, in a dose-dependent manner. In addition, key regulators of apoptosis, caspase-2 and caspase-8, were concomitantly up-regulated by these treatments. However, cranberry and grape seed extracts elicited differential effects on cell adhesion, cell morphology, and cell cycle regulatory pathways. This study represents one of the first comparative investigations of cranberry and grape seed extracts and their anti-proliferative effects on oral cancers. Previous findings using purified proanthocyanidin from grape seed extract demonstrated more prominent growth inhibition, as well as apoptosis-inducing, properties on CAL27 cells. These observations provide evidence that cranberry and grape seed extracts not only inhibit oral cancer proliferation but also that the mechanism of this inhibition may function by triggering key apoptotic regulators in these cell lines. This information will be of benefit to researchers interested in elucidating which dietary components are central to mechanisms involved in the mediation of oral carcinogenesis and progression.

  16. Mitochondrial localization of the low level p53 protein in proliferative cells

    International Nuclear Information System (INIS)

    p53 protein plays a central role in suppressing tumorigenesis by inducing cell cycle arrest or apoptosis through transcription-dependent and -independent mechanisms. Emerging publications suggest that following stress, a fraction of p53 translocates to mitochondria to induce cytochrome c release and apoptosis. However, the localization of p53 under unstressed conditions remains largely unexplored. Here we show that p53 is localized at mitochondria in absence of apoptotic stimuli, when cells are proliferating, localization observed in various cell types (rodent and human). This is also supported by acellular assays in which p53 bind strongly to mitochondria isolated from rat liver. Furthermore, the mitochondria subfractionation study and the alkaline treatment of the mitochondrial p53 revealed that the majority of mitochondrial p53 is present in the membranous compartments. Finally, we identified VDAC, a protein of the mitochondrial outer-membrane, as a putative partner of p53 in unstressed/proliferative cells.

  17. Asymmetric Cell Division in T Lymphocyte Fate Diversification.

    Science.gov (United States)

    Arsenio, Janilyn; Metz, Patrick J; Chang, John T

    2015-11-01

    Immunological protection against microbial pathogens is dependent on robust generation of functionally diverse T lymphocyte subsets. Upon microbial infection, naïve CD4(+) or CD8(+) T lymphocytes can give rise to effector- and memory-fated progeny that together mediate a potent immune response. Recent advances in single-cell immunological and genomic profiling technologies have helped elucidate early and late diversification mechanisms that enable the generation of heterogeneity from single T lymphocytes. We discuss these findings here and argue that one such mechanism, asymmetric cell division, creates an early divergence in T lymphocyte fates by giving rise to daughter cells with a propensity towards the terminally differentiated effector or self-renewing memory lineages, with cell-intrinsic and -extrinsic cues from the microenvironment driving the final maturation steps. PMID:26474675

  18. Proliferative activity of vervet monkey bone marrow-derived adherent cells

    International Nuclear Information System (INIS)

    Vervet monkey bone marrow-derived adherent cell population cultured in Fischer's medium supplemented with 12.5% fetal calf serum and 12.5% horse serum consists of two cell shapes: fusiform (type I) and polygonal (type II). Limiting-dilution cloning of the cells suggested that the two morphologically distinct cell types belong to the same cellular system even though they differ in their proliferative capabilities. The labeling index of type II cells, as measured by autoradiography, was found to be consistently lower than that of type I cells. It is probable that these two phenotypes represent different stages of differentiation, where progenitor type I gives rise to type II cells. The bone marrow-derived adherent cells were found to be cytokinetically at rest in vivo, using the thymidine suicide test, and relatively radioresistant with a D0 = 2.1 Gy and n = 2.36 at the time of explantation from the bone. Furthermore, in culture these cells are characterized by a relatively long cell cycle of 60 h, where the length of the S phase is 30 h, G2 is 12 h, M is 6 h, and G1 is 12 h. Thus, the vervet monkey bone marrow-derived adherent cells represent a cell population with a low turnover rate both in vivo and in vitro

  19. F-18-FDG positron emission tomography findings correlate pathological proliferative activity of oral squamous cell carcinoma

    International Nuclear Information System (INIS)

    It is still controversial whether fluorodeoxyglucose (FDG) uptake is correlated with cellular proliferation and prognosis of oral squamous cell carcinoma (OSC). In this study, we performed positron emission tomography (PET) study and immunohistochemical analysis to elucidate the relationship between FDG uptake and expression of cellular proliferative markers and pathological prognostic markers in patients with OSC. FDG PET and immunohistochemical staining have been carried out in sixteen patients with OSC. Tumor uptake of FDG was expressed with standardized uptake value (SUV). The expression of Ki-67, Topoisomerase IIα (Topo IIα), p53, and p63 in cancer cells was quantitatively assessed with positivity of the immunohistochemical staining. SUV was compared with the results of immunohistochemical analysis. FDG PET study revealed that SUV ranged from 3.6 to 22.1 with average of 10.4. Average positive rate of Ki-67, Topo IIα, p53, and p63 was 68.9%, 58.9%, 72.0%, and 65.2%, respectively. Pearson product-moment correlation coefficient analysis revealed that SUV was significantly correlated with Ki-67 (r=0.616, p=0.01), Topo IIα (r=0.677, p=0.004), p53 (r=0.613, p=0.01), and p63 (r=0.710, p=0.002), respectively. The present preliminary study indicated that FDG uptake was closely correlated with pathological cellular proliferative and prognostic markers in patients with OSC. (author)

  20. Immunity to leprosy. II. Genetic control of murine T cell proliferative responses to Mycobacterium leprae.

    Science.gov (United States)

    Douglas-Jones, A G; Watson, J D

    1985-10-01

    T cell proliferative responses to Mycobacterium leprae were measured after immunization of mice at the base of the tail with antigen and challenging lymphocytes from draining lymph nodes in culture with M. leprae. This T cell response to M. leprae has been compared in 18 inbred strains of mice. C57BL/10J mice were identified as low responder mice. The congenic strains B10.M and B10.Q were found to be high responders, whereas B10.BR and B10.P were low responders. F1 (B10.M X C57BL/10J) and F1 (B10.Q X C57BL/10J) hybrid mice were found to be low responders, similar to the C57BL/10J parent, indicating that the low responsive trait is dominant. Whereas B10.BR mice were shown to be low responders to M. leprae, B10.AKM and B10.A(2R) were clearly high responders, indicating that the H-2D region influences the magnitude of the T cell proliferative response. Gene complementation within the H-2 region was evident. Genes outside the H-2 region were also shown to influence the response to M. leprae. C3H/HeN were shown to be high responder mice, whereas other H-2k strains, BALB.K, CBA/N, and B10.BR, were low responders. Gene loci that influence the T cell proliferation assay have been discussed and were compared to known background genes which may be important for the growth of intracellular parasites. Because mycobacteria are intracellular parasites for antigen-presenting cells, genes that affect bacterial growth in these cells will also influence subsequent immune responses of the host. PMID:3928757

  1. Anti-proliferative action of silibinin on human colon adenomatous cancer HT-29 cells

    Directory of Open Access Journals (Sweden)

    Reyhan Akhtar

    2014-02-01

    Full Text Available Background: Silibinin a flavonoid from milk thistle (Silybum marianum exhibit a variety of pharmacological actions, including anti-proliferative and apoptotic activities against various types of cancers in intact animals and cancer cell lines. In the present study, the effect of silibinin on human colon cancer HT-29 cells was studied. Method: Incubations of cells with different silibinin concentrations (0.783-1,600 μg/ml for 24, 48 or 72 h showed a progressive decline in cell viability. Results: Loss of cell viability was time dependent and optimum inhibition of cell growth (78% was observed at 72 h. Under inverted microscope, the dead cells were seen as cell aggregates. IC50 (silibinin concentration killing 50% cells values were 180, 110 and 40μg/ml at 24, 48 and 72 h respectively. Conclusion: These findings re-enforce the anticancer potential of silibinin, as reported earlier for various other cancer cell lines (Ramasamy and Agarwal (2008, Cancer Letters, 269: 352-62.

  2. ARTEMIS stabilizes the genome and modulates proliferative responses in multipotent mesenchymal cells

    Directory of Open Access Journals (Sweden)

    Tompkins Kathleen

    2010-10-01

    Full Text Available Abstract Background Unrepaired DNA double-stranded breaks (DSBs cause chromosomal rearrangements, loss of genetic information, neoplastic transformation or cell death. The nonhomologous end joining (NHEJ pathway, catalyzing sequence-independent direct rejoining of DSBs, is a crucial mechanism for repairing both stochastically occurring and developmentally programmed DSBs. In lymphocytes, NHEJ is critical for both development and genome stability. NHEJ defects lead to severe combined immunodeficiency (SCID and lymphoid cancer predisposition in both mice and humans. While NHEJ has been thoroughly investigated in lymphocytes, the importance of NHEJ in other cell types, especially with regard to tumor suppression, is less well documented. We previously reported evidence that the NHEJ pathway functions to suppress a range of nonlymphoid tumor types, including various classes of sarcomas, by unknown mechanisms. Results Here we investigate roles for the NHEJ factor ARTEMIS in multipotent mesenchymal stem/progenitor cells (MSCs, as putative sarcomagenic cells of origin. We demonstrate a key role for ARTEMIS in sarcoma suppression in a sensitized mouse tumor model. In this context, we found that ARTEMIS deficiency led to chromosomal damage but, paradoxically, enhanced resistance and proliferative potential in primary MSCs subjected to various stresses. Gene expression analysis revealed abnormally regulated stress response, cell proliferation, and signal transduction pathways in ARTEMIS-defective MSCs. Finally, we identified candidate regulatory genes that may, in part, mediate a stress-resistant, hyperproliferative phenotype in preneoplastic ARTEMIS-deficient MSCs. Conclusions Our discoveries suggest that Art prevents genome damage and restrains proliferation in MSCs exposed to various stress stimuli. We propose that deficiency leads to a preneoplastic state in primary MSCs and is associated with aberrant proliferative control and cellular stress

  3. Epigenetic control of embryonic stem cell fate

    DEFF Research Database (Denmark)

    Christophersen, Nicolaj Strøyer; Helin, Kristian

    2010-01-01

    be induced rapidly to differentiate. Maintaining this balance of stability versus plasticity is a challenge, and extensive studies in recent years have focused on understanding the contributions of transcription factors and epigenetic enzymes to the "stemness" properties of these cells. Identifying...

  4. Azithromycin Synergistically Enhances Anti-Proliferative Activity of Vincristine in Cervical and Gastric Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xuezhang; Zhang, Yuyan; Li, Yong; Hao, Xiujing; Liu, Xiaoming, E-mail: erc1080@gmail.com; Wang, Yujiong, E-mail: erc1080@gmail.com [Key Laboratory of the Ministry of Education for the Conservation and Utilization of Special Biological Resources of Western China, Yinchuan 750021, Ningxia (China); College of Life Science, Ningxia University, Yinchuan 750021, Ningxia (China)

    2012-12-04

    In this study, the anti-proliferative and anticancer activity of azithromycin (AZM) was examined. In the presence of AZM, cell growth was inhibited more effectively in Hela and SGC-7901 cancer cells, relative to transformed BHK-21 cells. The respective 50% inhibition of cell growth (IC{sub 50}) values for Hela, SGC-7901 and BHK-21 were 15.66, 26.05 and 91.00 µg/mL at 72 h post incubation, indicative of a selective cytotoxicity against cancer cells. Cell apoptosis analysis using Hoechst nuclear staining and annexin V-FITC binding assay further demonstrated that AZM was capable of inducing apoptosis in both cancer cells and transformed cells. The apoptosis induced by AZM was partly through a caspase-dependent mechanism with an up-regulation of apoptotic protein cleavage PARP and caspase-3 products, as well as a down-regulation of anti-apoptotic proteins, Mcl-1, bcl-2 and bcl-X1. More importantly, a combination of AZM and a low dose of the common anti-cancer chemotherapeutic agent vincristine (VCR), produced a selectively synergistic effect on apoptosis of Hela and SGC-7901 cells, but not BHK-21 cells. In the presence of 12.50 μg/mL of VCR, the respective IC{sub 50} values of Hela, SGC-7901 and BHK-21 cells to AZM were reduced to 9.47 µg/mL, 8.43 µg/mL and 40.15 µg/mL at 72 h after the incubation, suggesting that the cytotoxicity of AZM had a selective anti-cancer effect on cancer over transformed cells in vitro. These results imply that AZM may be a potential anticancer agent for use in chemotherapy regimens, and it may minimize side effects via reduction of dosage and enhancing the effectiveness common chemotherapeutic drugs.

  5. Wnt signaling and the control of human stem cell fate.

    Science.gov (United States)

    Van Camp, J K; Beckers, S; Zegers, D; Van Hul, W

    2014-04-01

    Wnt signaling determines major developmental processes in the embryonic state and regulates maintenance, self-renewal and differentiation of adult mammalian tissue stem cells. Both β-catenin dependent and independent Wnt pathways exist, and both affect stem cell fate in developing and adult tissues. In this review, we debate the response to Wnt signal activation in embryonic stem cells and human, adult stem cells of mesenchymal, hematopoetic, intestinal, gastric, epidermal, mammary and neural lineages, and discuss the need for Wnt signaling in these cell types. Due to the vital actions of Wnt signaling in developmental and maintenance processes, deregulation of the pathway can culminate into a broad spectrum of developmental and genetic diseases, including cancer. The way in which Wnt signals can feed tumors and maintain cancer stem stells is discussed as well. Manipulation of Wnt signals both in vivo and in vitro thus carries potential for therapeutic approaches such as tissue engineering for regenerative medicine and anti-cancer treatment. Although many questions remain regarding the complete Wnt signal cell-type specific response and interplay of Wnt signaling with pathways such as BMP, Hedgehog and Notch, we hereby provide an overview of current knowledge on Wnt signaling and its control over human stem cell fate. PMID:24323281

  6. Induction of IgA and sustained deficiency of cell proliferative response in chronic hepatitis C

    Institute of Scientific and Technical Information of China (English)

    Yalena Amador-Ca(n)izares; Liz Alvarez-Lajonchere; Ivis Guerra; Ingrid Rodnguez-Alonso; Gillian Martínez-Donato; Julián Triana; Eddy E González-Horta; Angel Pérez; Santiago Due(n)as-Carrera

    2008-01-01

    AIM: In the present study, antibody and peripheral blood mononuclear cells (PBMC) proliferative responses against hepatitis C virus (HCV) antigens were evaluated in HCV chronically infected patients. METHODS: Paired serum and PBMC samples were taken six months apart from 34 individuals, either treated or not, and tested by enzyme-linked immunosorbent assay (ELISA) and carboxyfluorescein succinimidyl ester staining.RESULTS: Over 70% of the patients showed specific IgG and IgM against capsid, E1 and NS3, while HVR-1 was recognized by half of the patients. An increase in the levels of the anti-capsid IgM (P = 0.027) and IgG (P=0.0006) was observed in six-month samples, compared to baseline. Similarly, a significantly higher percent of patients had detectable IgA reactivity to capsid (P=0.017) and NS3 (P=0.005) after six months, compared to baseline. Particularly, IgA against structural antigens positively correlated with hepatic damage (P=0.036). IgG subclasses evaluation against capsid and NS3 revealed a positive recognition mediated by IgG1 in more than 80% of the individuals. On the contrary, less than 30% of the patients showed a positive proliferative response either of CD4+ or CD8+ T cells, being the capsid poorly recognized. CONCLUSION: These results confirm that while the cellular immune response is narrow and weak, a broad and vigorous humoral response occurs in HCV chronic infection. The observed correlation between IgA and hepatic damage may have diagnostic significance, although it warrants further confirmation.

  7. Evidence for a new segregant series of B cell antigens that are encoded in the HLA-D region and that stimulate secondary allogenic proliferative and cytotoxic responses

    OpenAIRE

    1980-01-01

    Five new histocompatibility antigens, designated secondary B cell or (SB) antigens, have been identified by secondary allogeneic proliferative and cytotoxic responses. The reagents used to define the SB antigents are lymphocytes primed between donors matched for all known HLA antigens. The SB antigens stimulate weak primary allogeneic proliferative responses (a mean relative response of 8%) but strong secondary proliferative responses. Strong secondary cell-mediated cytotoxicity is generated ...

  8. Anti-proliferative effects of Bifidobacterium adolescentis SPM0212 extract on human colon cancer cell lines

    International Nuclear Information System (INIS)

    Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as anti-tumor activity. The aim of the present work was to study the growth inhibition of tumor cells by butanol extract of Bifidobacterium adolescentis isolated from healthy young Koreans. The anti-proliferative activity of B. adolescentis isolates was assessed by XTT assays on three human colon cancer cell lines (Caco-2, HT-29, and SW480). The effects of B. adolescentis SPM0212 butanol extract on tumor necrosis factor-α (TNF-α) and nitric oxide (NO) production were tested using the murine macrophage RAW 264.7 cell line. The butanol extract of B. adolescentis SPM0212 dose-dependently inhibited the growth of Caco-2, HT-29, and SW480 cells by 70%, 30%, and 40%, respectively, at 200 μg/mL. Additionally, the butanol extract of B. adolescentis SPM0212 induced macrophage activation and significantly increased the production of TNF-α and NO, which regulate immune modulation and are cytotoxic to tumor cells. The butanol extract of B. adolescentis SPM0212 increased activity of the host immune system and may improve human health by helping to prevent colon cancer as a biological response modifier

  9. Anti-proliferative effects of Bifidobacterium adolescentis SPM0212 extract on human colon cancer cell lines

    Directory of Open Access Journals (Sweden)

    Chung Myung

    2008-10-01

    Full Text Available Abstract Background Lactic acid bacteria (LAB are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as anti-tumor activity. The aim of the present work was to study the growth inhibition of tumor cells by butanol extract of Bifidobacterium adolescentis isolated from healthy young Koreans. Methods The anti-proliferative activity of B. adolescentis isolates was assessed by XTT assays on three human colon cancer cell lines (Caco-2, HT-29, and SW480. The effects of B. adolescentis SPM0212 butanol extract on tumor necrosis factor-α (TNF-α and nitric oxide (NO production were tested using the murine macrophage RAW 264.7 cell line. Results The butanol extract of B. adolescentis SPM0212 dose-dependently inhibited the growth of Caco-2, HT-29, and SW480 cells by 70%, 30%, and 40%, respectively, at 200 μg/mL. Additionally, the butanol extract of B. adolescentis SPM0212 induced macrophage activation and significantly increased the production of TNF-α and NO, which regulate immune modulation and are cytotoxic to tumor cells. Conclusion The butanol extract of B. adolescentis SPM0212 increased activity of the host immune system and may improve human health by helping to prevent colon cancer as a biological response modifier.

  10. Immunochemical expression of proliferative cell nuclear antigen in aging cultured astrocytes

    Directory of Open Access Journals (Sweden)

    M. C. Vanzani

    2003-08-01

    Full Text Available Cell differentiation degree and mitotic activity were sequentially assessed by immunoperoxidase labeling of glial fibrillary acidic protein (GFAP and proliferative cell nuclear antigen (PCNA, respectively, in rat brain cultured astrocytes maintained up to 60 days in vitro (DIV of first subculture, or weekly passaged until their 12th subculture. Cell count was performed through a 0.01 mm2 section reticule and morphometric analysis with a stereological grid. The number of double immunoreactive cells peaked by 2 DIV to achieve its lowest value at 60 DIV. At 24 hs of cell seeding of successive passages, such values peaked by the 6th subculture to gradually decrease thereafter. Increasing cell hypertrophy was found during the long-term first subculture but not after passaging. At the end of the observation period, doubly immunolabeled astrocytes were still recorded, thus evidencing retention of proliferative potential despite aging.El grado de diferenciación celular y la actividad mitótica fueron secuencialmente determinados mediante marcación por inmunoperoxidasa de la proteína gliofibrilar ácida (GFAP y del antígeno nuclear de proliferación celular (PCNA, respectivamente, en cultivos astrocitarios obtenidos de encéfalo de rata y mantenidos hasta 60 días in vitro (DIV de su primer subcultivo, o mediante pasajes semanales hasta el 12do subcultivo. El conteo celular se realizó mediante una retícula de 0.01-mm2 de sección y el análisis morfométrico con una grilla estereológica. El número de células doblemente inmunorreactivas alcanzó valores máximos a los 2 DIV para descender a los menores a los 60 DIV. A las 24 hs de sembrado celular de los sucesivos pasajes, esos valores ascendieron hacia el 6to subcultivo para luego declinar. En cuanto a la hipertrofia celular, se observó en todo el curso del primer subcultivo, pero no durante los posteriores pasajes. Al final del período de observación, todavía se continuaban detectando

  11. Anti-Proliferative Effect of Rosmarinus officinalis L. Extract on Human Melanoma A375 Cells.

    Directory of Open Access Journals (Sweden)

    Lucia Cattaneo

    Full Text Available Rosemary (Rosmarinus officinalis L. has been used since ancient times in traditional medicine, while nowadays various rosemary formulations are increasingly exploited by alternative medicine to cure or prevent a wide range of health disorders. Rosemary's bioproperties have prompted scientific investigation, which allowed us to ascertain antioxidant, anti-inflammatory, cytostatic, and cytotoxic activities of crude extracts or of pure components. Although there is a growing body of experimental work, information about rosemary's anticancer properties, such as chemoprotective or anti-proliferative effects on cancer cells, is very poor, especially concerning the mechanism of action. Melanoma is a skin tumor whose diffusion is rapidly increasing in the world and whose malignancy is reinforced by its high resistance to cytotoxic agents; hence the availability of new cytotoxic drugs would be very helpful to improve melanoma prognosis. Here we report on the effect of a rosemary hydroalcoholic extract on the viability of the human melanoma A375 cell line. Main components of rosemary extract were identified by liquid chromatography coupled to tandem mass spectrometry (LC/ESI-MS/MS and the effect of the crude extract or of pure components on the proliferation of cancer cells was tested by MTT and Trypan blue assays. The effect on cell cycle was investigated by using flow cytometry, and the alteration of the cellular redox state was evaluated by intracellular ROS levels and protein carbonylation analysis. Furthermore, in order to get information about the molecular mechanisms of cytotoxicity, a comparative proteomic investigation was performed.

  12. Anti-Proliferative Effect of Rosmarinus officinalis L. Extract on Human Melanoma A375 Cells.

    Science.gov (United States)

    Cattaneo, Lucia; Cicconi, Rosella; Mignogna, Giuseppina; Giorgi, Alessandra; Mattei, Maurizio; Graziani, Giulia; Ferracane, Rosalia; Grosso, Alessandro; Aducci, Patrizia; Schininà, M Eugenia; Marra, Mauro

    2015-01-01

    Rosemary (Rosmarinus officinalis L.) has been used since ancient times in traditional medicine, while nowadays various rosemary formulations are increasingly exploited by alternative medicine to cure or prevent a wide range of health disorders. Rosemary's bioproperties have prompted scientific investigation, which allowed us to ascertain antioxidant, anti-inflammatory, cytostatic, and cytotoxic activities of crude extracts or of pure components. Although there is a growing body of experimental work, information about rosemary's anticancer properties, such as chemoprotective or anti-proliferative effects on cancer cells, is very poor, especially concerning the mechanism of action. Melanoma is a skin tumor whose diffusion is rapidly increasing in the world and whose malignancy is reinforced by its high resistance to cytotoxic agents; hence the availability of new cytotoxic drugs would be very helpful to improve melanoma prognosis. Here we report on the effect of a rosemary hydroalcoholic extract on the viability of the human melanoma A375 cell line. Main components of rosemary extract were identified by liquid chromatography coupled to tandem mass spectrometry (LC/ESI-MS/MS) and the effect of the crude extract or of pure components on the proliferation of cancer cells was tested by MTT and Trypan blue assays. The effect on cell cycle was investigated by using flow cytometry, and the alteration of the cellular redox state was evaluated by intracellular ROS levels and protein carbonylation analysis. Furthermore, in order to get information about the molecular mechanisms of cytotoxicity, a comparative proteomic investigation was performed. PMID:26176704

  13. Proliferative response of human prostate cancer cell to hormone inhibited by androgen receptor antisense RNA

    Institute of Scientific and Technical Information of China (English)

    江军; 王洛夫; 方玉华; 靳风烁; 靳文生

    2004-01-01

    Background The failure of endocrine treatment for advanced prostate cancer might be related to aberrant activation of androgen receptor (AR). Prostate cancer cell line LNCaP contains AR that can be activated by androgen, estrogen and progesterone. This study was set to investigate the effects of antisense AR RNA on growth of LNCaP cultured in medium containing varied concentrations of R1881, 17β-estradiol, and progesterone, respectively. Methods LNCaP cells transfected with antisense AR RNA retroviral vector pL-AR-SN were designated as LNCaPas-AR. LNCaP cells containing empty vector pLXSN served as LNCaPNeo. LNCaP and LNCaPNeo were taken as controls. In vitro cell growth assay, proliferative cells of LNCaP and tranfected LNCaPs were counted by typan staining when they cultured with synthetic androgen R1881, 17β-estradiol, and progesterone, respectively. Results Growth of LNCaPas-AR was inhibited significantly (P<0.05) compared with that of LNCaP and LNCaPNeo at 1 nmol/L R1881, 10 nmol/L 17β-estradiol, and 1 nmol/L progesterone, respectively. No difference was seen between LNCaP and LNCaPNeo(P>0.05). Microscopic observation showed that LNCaP and LNCaPNeo cells grew well, but only few LNCaPas-AR cells were alive. Conclusions Our observations indicate that antisense AR RNA retroviral vector pL-AR-SN could change androgen-independent characteristics of LNCaP cells, which might shed some novel insights into the treatment of androgen-independent prostate cancer.

  14. Evaluation of viability and proliferative activity of human urothelial cells cultured onto xenogenic tissue-engineered extracellular matrices.

    LENUS (Irish Health Repository)

    Davis, Niall F

    2011-04-01

    To evaluate the viability and proliferative activity of human urothelial cells (HUCs) cultured on tissue-engineered extracellular matrix scaffolds and to assess the potential of extracellular matrixes to support the growth of HUCs in their expected in vivo urine environment.

  15. Evaluation of cell proliferative activity after irradiation using immunohistochemical approach and flow cytometry

    International Nuclear Information System (INIS)

    To evaluate a proliferative activity of post-irradiated malignant cells, we studied the kinetics of HeLa cells using immunohistochemical approach and flow cytometry. HeLa cells were stained with two proliferation-associated monoclonal antibodies, Ki-67 and anti-DNA polymerase α antibody. Nucleoli of non-irradiated cells were granularly stained with Ki-67. After irradiation, only the center of nuclei was diffusely stained with Ki-67. One hundred forty-four hours after low-dose irradiation, the staining patterns became the same as the control. On the other hand, after high-dose irradiation, the center of nuclei was weakly stained. DNA polymerase α was diffusely labelled with nuclei of the control. It was located around the border of nuclei of low-dose irradiated cells like a ring. But after high-dose irradiation, it was granularly distributed in the periphery of nuclei. FITC conjugated Ki-67/PI two parameter analysis was done by a single laser flow cytometer. Twenty-four hours after irradiation, DNA-histograms showed the accumulation to G2/M phase and the increase of DNA content of G2/M cells, as exposure dose was increased. Two parameter analysis showed the increase of FITC uptake of G2/M phase as dose increased. These changes of flow cytometry were remarkably observed after 24 hours' incubation. It was shown that the difference of Ki-67 antigen and DNA polymerase α appearance depended on the irradiation dose. These findings suggest that immunohistochemical staining with Ki-67 or anti-DNA polymerase α antibody and flow cytometry using Ki-67 are available to evaluate cell damages after irradiation. (author)

  16. Immunophenotyping and T-cell proliferative capacity in a healthy aged population.

    Science.gov (United States)

    Peres, Alessandra; Bauer, Moisés; da Cruz, Ivana Beatrice; Nardi, Nance Beyer; Chies, José Artur Bogo

    2003-01-01

    The age-related decline of immunological functions is well established but it remains largely unknown which specific changes are related to disease. We analyzed peripheral blood lymphocytes of 42 healthy elderly as well as 24 healthy young subjects from southern Brazil. No differences in phytohemagglutinin-induced proliferation and CD4:CD8 ratio were found between the subjects. However, CD4 expression (considering mean fluorescence intensity) was found upregulated in elderly subjects. No changes in activation molecules CD25, CD28, CD69 and CD95 were observed. A reduced proportion of naive (CD45RA+) T cells was found in the elderly compared to young subjects. No changes in adhesion molecule expression (CD11c and CD31) were observed. However, the frequencies of CD49d-positive cells, as well as expression of CD62L, were increased in the eldery subjects. We further described two subgroups of eldery subjects with an immunological risk profile defined by lower CD4:CD8 ratio and reduced proliferative response to mitogens. These data suggest that healthy aging is associated with intact T-cell proliferation and some compensatory immunophenotypical changes. PMID:14618026

  17. Structural and functional development of rat and mouse gastric mucous cells in relation to their proliferative activity

    International Nuclear Information System (INIS)

    An investigation has been carried out to find a relation between the differentiation and the mitotic activity of gastric mucous cells of the rat and the mouse. It is shown that the bulk mucous production is carried out by the older, non-proliferative, surface mucous cells that line the foveolae and the gastric surface. One experiment describes the renewal of mouse gastric mucous cells following fast neutron irradiation. (C.F.)

  18. Murine regulatory T cells contain hyper-proliferative and death-prone subsets with differential ICOS expression

    OpenAIRE

    Chen, Yong; Shen, Shudan; Gorentla, Balachandra; Gao, Jimin; Zhong, Xiao-Ping

    2012-01-01

    Regulatory T cells (Treg) are crucial for self-tolerance. It has been an enigma that Treg exhibit an anergic phenotype reflected by hypo-proliferation in vitro following T cell receptor (TCR) stimulation but undergo vigorous proliferation in vivo. We report here that, different from conventional T cells (Tcon), murine Treg are prone to death but hyper-proliferative in vitro and in vivo. During in vitro culture, most Treg die with or without TCR stimulation, correlated with constitutive activa...

  19. Erythropoietin guides multipotent hematopoietic progenitor cells toward an erythroid fate

    Science.gov (United States)

    Grover, Amit; Mancini, Elena; Moore, Susan; Mead, Adam J.; Atkinson, Deborah; Rasmussen, Kasper D.; O’Carroll, Donal; Jacobsen, Sten Eirik W.

    2014-01-01

    The erythroid stress cytokine erythropoietin (Epo) supports the development of committed erythroid progenitors, but its ability to act on upstream, multipotent cells remains to be established. We observe that high systemic levels of Epo reprogram the transcriptomes of multi- and bipotent hematopoietic stem/progenitor cells in vivo. This induces erythroid lineage bias at all lineage bifurcations known to exist between hematopoietic stem cells (HSCs) and committed erythroid progenitors, leading to increased erythroid and decreased myeloid HSC output. Epo, therefore, has a lineage instructive role in vivo, through suppression of non-erythroid fate options, demonstrating the ability of a cytokine to systematically bias successive lineage choices in favor of the generation of a specific cell type. PMID:24493804

  20. Relationship between proliferative activity of cancer cells and clinicopathological factors in patients with esophageal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    Jun-Xing Huang; Wei Yan; Zheng-Xiang Song; Rong-Yu Qian; Ping Chen; Eeva Salminen; Jorma Toppari

    2005-01-01

    AIM: To assess whether the molecular markers of malignant tumors could improve the understanding of tumor characteristics, and to observe the characteristics of expression of cell cycle markers Ki-67 and cydin A in esophageal carcinoma and to analyze the relationship between proliferative activity of cancer cells and clinicopathological factors.METHODS: Seventy of surgically resected esophageal squamous cell carcinoma (SCC) were examined by immunohistochemistry utilizing commercially available antibodies. Nuclear staining was regarded as a positive result. At least 50 fields in each tumor and non-tumor section were evaluated at a medium power (x200) to determine the proportion of tumor cells and the staining intensity of nuclei in the entire sections.RESULTS: Ki-67 and cyclin A were only expressed in base cells of normal esophageal mucosa. The positive immunostaining of nuclei of SCC was significantly higher than that in normal esophageal mucosa (t= 13.32 and t= 7.52,respectively, P<0.01). The distribution of positively stained was more diffuse and stronger in poorly differentiated SCC. Both Ki-67 and cyclin A expressions were related to histological grades of tumors (t = 3.5675 and t = 3.916; t= 2.13, respectively, P<0.05) but not to the sex and age of the patients, tumor size, lymphatic invasion, location, or stage grouping.CONCLUSION: The proliferative activity of cancer cells may be understood by immunohistochemistry of Ki-67 and cyclin A in Chinese patients with esophageal SCC. These cell cycle markers may serve as an indicator of cancer cell proliferation rate. The overexpression of cell cycle markers Ki-67 and cyclin A suggests the poor SCC differentiation in patients with esophageal carcinoma.

  1. Spatially patterned matrix elasticity directs stem cell fate

    Science.gov (United States)

    Yang, Chun; DelRio, Frank W.; Ma, Hao; Killaars, Anouk R.; Basta, Lena P.; Kyburz, Kyle A.; Anseth, Kristi S.

    2016-01-01

    There is a growing appreciation for the functional role of matrix mechanics in regulating stem cell self-renewal and differentiation processes. However, it is largely unknown how subcellular, spatial mechanical variations in the local extracellular environment mediate intracellular signal transduction and direct cell fate. Here, the effect of spatial distribution, magnitude, and organization of subcellular matrix mechanical properties on human mesenchymal stem cell (hMSCs) function was investigated. Exploiting a photodegradation reaction, a hydrogel cell culture substrate was fabricated with regions of spatially varied and distinct mechanical properties, which were subsequently mapped and quantified by atomic force microscopy (AFM). The variations in the underlying matrix mechanics were found to regulate cellular adhesion and transcriptional events. Highly spread, elongated morphologies and higher Yes-associated protein (YAP) activation were observed in hMSCs seeded on hydrogels with higher concentrations of stiff regions in a dose-dependent manner. However, when the spatial organization of the mechanically stiff regions was altered from a regular to randomized pattern, lower levels of YAP activation with smaller and more rounded cell morphologies were induced in hMSCs. We infer from these results that irregular, disorganized variations in matrix mechanics, compared with regular patterns, appear to disrupt actin organization, and lead to different cell fates; this was verified by observations of lower alkaline phosphatase (ALP) activity and higher expression of CD105, a stem cell marker, in hMSCs in random versus regular patterns of mechanical properties. Collectively, this material platform has allowed innovative experiments to elucidate a novel spatial mechanical dosing mechanism that correlates to both the magnitude and organization of spatial stiffness. PMID:27436901

  2. Nuclear Morphometry in Ductal Breast Carcinoma with Correlation to Cell Proliferative Activity and Prognosis

    International Nuclear Information System (INIS)

    Morphometry is the quantitative description of biologic structures. This study was designed to evaluate the efficiency of morphometric measurements in diagnosis and prognosis of patients with breast carcinoma. Methods: Histological samples from 61 patients of invasive duct carcinoma (IDC) of no special type (NST), 12 cases of ductal carcinoma in situ (DCIS) and 14 control breast samples taken from fibrocystic change disease were retrospectively analyzed by computerized nuclear morphometry. All IDC patients underwent modified radical mastectomy without preoperative chemotherapy. The mean follow up was 28±19 months (range] -71). In each case, 25-50 nuclei were measured and the mean nuclear area (MNA), mean nuclear perimeter (MNP), mean maximum nuclear diameter (MMNO) and mean minimal nuclear diameter (Mmnd) were measured. The mean axis ratio (MAR), mean nuclear compactness (MNC), mean nuclear size (MNS) and mean shape factor (MSHF), were calculated mathematically. To measure the nuclear diameters, a new method was employed using the AutoCAD program. Morphometric parameters were compared with different clinico pathologic features, patient's survival and cell proliferative activity as determined by Ki-67 immunostaining which was evaluated quantitatively. Most of the morphometric parameters were significantly higher in DCIS and IDC groups than benign one. In IDC group morphometric features related to nuclear size (MNA, MNP, MMNO, Mmnd and MNS) were significantly correlated to most clinico pathologic features and cell proliferative activity assessed by Ki-67 immunostaining. However, the shape factor failed to achieve this correlation. The univariate analysis using Kaplan Meier curves indicated that short survival time was correlated with high nuclear morphometric values (MNA. MNP, MMND, Mmnd, MNS and MSHF). Moreover, the Spear man correlation analysis showed that Mmnd has the highest converse correlation with survival (r= -0.75, (ρ < 0.0001). In multivariate analysis

  3. Control of Cell Fate in the Circulatory and Ventilatory Systems

    CERN Document Server

    Thiriet, Marc

    2012-01-01

    The volumes in this authoritative series present a multidisciplinary approach to modeling and simulation of flows in the cardiovascular and ventilatory systems, especially multiscale modeling and coupled simulations. The cardiovascular and respiratory systems are tightly coupled, as their primary function is to supply oxygen to and remove carbon dioxide from the body's cells. Because physiological conduits have deformable and reactive walls, macroscopic flow behavior and prediction must be coupled to nano- and microscopic events in a corrector scheme of regulated mechanisms. Therefore, investigation of flows of blood and air in physiological conduits requires an understanding of the biology, chemistry, and physics of these systems together with the mathematical tools to describe their functioning. Volumes 1 and 2 are devoted to cell organization and fate, as well as activities that are autoregulated and/or controlled by the cell environment. Volume 1 examined cellular features that allow adaptation to env...

  4. Notch1 is required in newly postmitotic cells to inhibit the rod photoreceptor fate

    OpenAIRE

    Mizeracka, Karolina; DeMaso, Christina R.; Cepko, Constance L.

    2013-01-01

    Several models of cell fate determination can be invoked to explain how single retinal progenitor cells (RPCs) produce different cell types in a terminal division. To gain insight into this process, the effects of the removal of a cell fate regulator, Notch1, were studied in newly postmitotic cells using a conditional allele of Notch1 (N1-CKO) in mice. Almost all newly postmitotic N1-CKO cells became rod photoreceptors, whereas wild-type (WT) cells achieved a variety of fates. Single cell pro...

  5. Evaluation of the Anti-proliferative Effects of Ophiocoma erinaceus Methanol Extract Against Human Cervical Cancer Cells

    OpenAIRE

    Baharara, Javad; Amini, Elaheh; Namvar, Farideh

    2016-01-01

    Background: Marine organisms provide appreciable source of novel bioactive compounds with pharmacological potential. There is little information in correlation with anti-cancer activities of brittle star. In the present study, anti-neoplastic efficacy of Ophiocoma erinaceus methanol extract against human cervical cancer cells was investigated. Methods: The HeLa cells were cultured and exposed to brittle star methanol extract for 24 and 48 hr. The anti-proliferative properties were examined by...

  6. Nuclear Morphometry and Ki67 Proliferative Marker in Renal Clear Cell Carcinoma

    International Nuclear Information System (INIS)

    Different grading systems for renal cell carcinoma (RCC) were proposed to assess patients' outcome. lnterobserver variability interfere with the widespread acceptance. Study of the tumor proliferative activity could provide another parameter for predicting biologic aggression and subsequent prognosis. Patients and Methods: Twenty patients who underwent radical nephrectomy for RCC were selected for histopathologic study. Normal tissue beneath the neoplasm in 5 specimen was used as control. Nuclear morphometry was carried by using CAS 200 image analysis system. Cellular proliferation was examined by immunohistochemistry, using Ki67 (MIB-I) monoclonal antibody on paraffin embedded tissue. All data were subjected to statistical evaluation. The mean nuclear area was significantly increased versus normal nuclei (ρ=0.0001). It was significant in relation to patients' survival. There was significant increased nuclear area with advancing stages (means =51.85±14.3 μm2, 75.50±12.8 μm2 and 116.35±7.16 μm2) and grade III tumors (mean = 116.27±7.08 μm2). There was an insignificant difference between grades I and II (59.96±17.16 μm2 and 62.34±20.22 μm2 respectively). The mean nuclear diameter was significantly increased with stage IIIa while no difference was noticed between stage I and II (20.29 ± 0.92 μm, 14.31±2.44 μm and 13.33±1.54 μm respectively). Tumor grading was significant in relation to the mean nuclear diameter (14.3±2.44 μm, 15.33 ±1.45 μm and 20.29±0.92 μm). The mean Ki67 (MIBI) proliferative index (PI) was significantly increased in the tumor versus control region (ρ=0.0001). Ki 67 PI was significant in relation to stage (9. 8.89%, 45.98±4.43% and 58.67±6.23%), (ρ=0.0001). However, PI was significantly increased with grade III tumors without a significant difference between grade I and II (ρ=0.02). Morphometric nuclear area and Ki67 proliferation index could provide reliable information that complements the other parameter to assess

  7. Regulation of VEGF and bFGF mRNA expression and other proliferative compounds in skeletal muscle cells.

    Science.gov (United States)

    Jensen, L; Schjerling, P; Hellsten, Y

    2004-01-01

    The role of muscle contraction, prostanoids, nitric oxide and adenosine in the regulation of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and endothelial cell proliferative compounds in skeletal muscle cell cultures was examined. VEGF and bFGF mRNA, protein release as well as the proliferative effect of extracellular medium was determined in non-stimulated and electro-stimulated rat and human skeletal muscle cells. In rat skeletal muscle cells these aspects were also determined after treatment with inhibitors and/or donors of nitric oxide (NO), prostanoids and adenosine. Electro-stimulation caused an elevation in the VEGF and bFGF mRNA levels of rat muscle cells by 33% and 43% (P < 0.05), respectively, and in human muscle cells VEGF mRNA was elevated by 24%. Medium from electro-stimulated human, but not rat muscle cells induced a 126% higher (P < 0.05) endothelial cell proliferation than medium from non-stimulated cells. Cyclooxygenase inhibition of rat muscle cells induced a 172% increase (P < 0.05) in VEGF mRNA and a 104% increase in the basal VEGF release. Treatment with the NO donor SNAP (0.5 microM) decreased (P < 0.05) VEGF and bFGF mRNA by 42 and 38%, respectively. Medium from SNAP treated muscle cells induced a 45% lower (P < 0.05) proliferation of endothelial cells than control medium. Adenosine enhanced the basal VEGF release from muscle cells by 75% compared to control. The present data demonstrate that contractile activity, NO, adenosine and products of cyclooxygenase regulate the expression of VEGF and bFGF mRNA in skeletal muscle cells and that contractile activity and NO regulate endothelial cell proliferative compounds in muscle extracellular fluid. PMID:15609080

  8. An exquisite cross-control mechanism among endothelial cell fate regulators directs the plasticity and heterogeneity of lymphatic endothelial cells

    Science.gov (United States)

    Kang, Jinjoo; Yoo, Jaehyuk; Lee, Sunju; Tang, Wanli; Aguilar, Berenice; Ramu, Swapnika; Choi, Inho; Otu, Hasan H.; Shin, Jay W.; Dotto, G. Paolo; Koh, Chester J.; Detmar, Michael

    2010-01-01

    Arteriovenous-lymphatic endothelial cell fates are specified by the master regulators, namely, Notch, COUP-TFII, and Prox1. Whereas Notch is expressed in the arteries and COUP-TFII in the veins, the lymphatics express all 3 cell fate regulators. Previous studies show that lymphatic endothelial cell (LEC) fate is highly plastic and reversible, raising a new concept that all 3 endothelial cell fates may coreside in LECs and a subtle alteration can result in a reprogramming of LEC fate. We provide a molecular basis verifying this concept by identifying a cross-control mechanism among these cell fate regulators. We found that Notch signal down-regulates Prox1 and COUP-TFII through Hey1 and Hey2 and that activated Notch receptor suppresses the lymphatic phenotypes and induces the arterial cell fate. On the contrary, Prox1 and COUP-TFII attenuate vascular endothelial growth factor signaling, known to induce Notch, by repressing vascular endothelial growth factor receptor-2 and neuropilin-1. We show that previously reported podoplanin-based LEC heterogeneity is associated with differential expression of Notch1 in human cutaneous lymphatics. We propose that the expression of the 3 cell fate regulators is controlled by an exquisite feedback mechanism working in LECs and that LEC fate is a consequence of the Prox1-directed lymphatic equilibrium among the cell fate regulators. PMID:20351309

  9. Severe proliferative retinopathy is associated with blood hyperviscosity in sickle cell hemoglobin-C disease but not in sickle cell anemia. : Sickle cell disease and retinopathy

    OpenAIRE

    Lemaire, Clément; Lamarre, Yann; Lemonne, Nathalie; Waltz, Xavier; Chahed, Sadri; Cabot, Florence; Botez, Ioana; Tressieres, Benoit; Lalanne-Mistrih, Marie-Laure; Etienne-Julan, Maryse; Connes, Philippe

    2012-01-01

    International audience Little is known about the impact of blood rheology on the occurrence of retinopathy in sickle cell disease (SCD). Fifty-nine adult SCD patients in steady-state condition participated to the study: 32 with homozygous SCD (sickle cell anemia; SCA) and 27 with sickle cell hemoglobin-C disease (SCC). The patients underwent retinal examination and were categorized according to the classification of Goldberg: 1) no retinopathy (group 1), 2) non-proliferative or proliferati...

  10. Quantifying intrinsic and extrinsic control of single-cell fates in cancer and stem/progenitor cell pedigrees with competing risks analysis

    OpenAIRE

    J. A. Cornwell; Hallett, R. M.; S. Auf der Mauer; A. Motazedian; Schroeder, T.; J. S. Draper; Harvey, R. P.; R. E. Nordon

    2016-01-01

    The molecular control of cell fate and behaviour is a central theme in biology. Inherent heterogeneity within cell populations requires that control of cell fate is studied at the single-cell level. Time-lapse imaging and single-cell tracking are powerful technologies for acquiring cell lifetime data, allowing quantification of how cell-intrinsic and extrinsic factors control single-cell fates over time. However, cell lifetime data contain complex features. Competing cell fates, censoring, an...

  11. Increased Stiffness in Aged Skeletal Muscle Impairs Muscle Progenitor Cell Proliferative Activity.

    Directory of Open Access Journals (Sweden)

    Grégory Lacraz

    Full Text Available Skeletal muscle aging is associated with a decreased regenerative potential due to the loss of function of endogenous stem cells or myogenic progenitor cells (MPCs. Aged skeletal muscle is characterized by the deposition of extracellular matrix (ECM, which in turn influences the biomechanical properties of myofibers by increasing their stiffness. Since the stiffness of the MPC microenvironment directly impacts MPC function, we hypothesized that the increase in muscle stiffness that occurs with aging impairs the behavior of MPCs, ultimately leading to a decrease in regenerative potential.We showed that freshly isolated individual myofibers from aged mouse muscles contain fewer MPCs overall than myofibers from adult muscles, with fewer quiescent MPCs and more proliferative and differentiating MPCs. We observed alterations in cultured MPC behavior in aged animals, where the proliferation and differentiation of MPCs were lower and higher, respectively. These alterations were not linked to the intrinsic properties of aged myofibers, as shown by the similar values for the cumulative population-doubling values and fusion indexes. However, atomic force microscopy (AFM indentation experiments revealed a nearly 4-fold increase in the stiffness of the MPC microenvironment. We further showed that the increase in stiffness is associated with alterations to muscle ECM, including the accumulation of collagen, which was correlated with higher hydroxyproline and advanced glycation end-product content. Lastly, we recapitulated the impaired MPC behavior observed in aging using a hydrogel substrate that mimics the stiffness of myofibers.These findings provide novel evidence that the low regenerative potential of aged skeletal muscle is independent of intrinsic MPC properties but is related to the increase in the stiffness of the MPC microenvironment.

  12. GTP depletion synergizes the anti-proliferative activity of chemotherapeutic agents in a cell type-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Tao; Meng, Lingjun [Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A and M Health Science Center, Houston, TX 77030 (United States); Tsai, Robert Y.L., E-mail: rtsai@ibt.tamhsc.edu [Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A and M Health Science Center, Houston, TX 77030 (United States)

    2011-10-22

    Highlights: {yields} Strong synergy between mycophenolic acid (MPA) and 5-FU in MDA-MB-231 cells. {yields} Cell type-dependent synergy between MPA and anti-proliferative agents. {yields} The synergy of MPA on 5-FU is recapitulated by RNA polymerase-I inhibition. {yields} The synergy of MPA on 5-FU requires the expression of nucleostemin. -- Abstract: Mycophenolic acid (MPA) depletes intracellular GTP by blocking de novo guanine nucleotide synthesis. GTP is used ubiquitously for DNA/RNA synthesis and as a signaling molecule. Here, we made a surprising discovery that the anti-proliferative activity of MPA acts synergistically with specific chemotherapeutic agents in a cell type-dependent manner. In MDA-MB-231 cells, MPA shows an extremely potent synergy with 5-FU but not with doxorubicin or etoposide. The synergy between 5-FU and MPA works most effectively against the highly tumorigenic mammary tumor cells compared to the less tumorigenic ones, and does not work in the non-breast cancer cell types that we tested, with the exception of PC3 cells. On the contrary, MPA shows the highest synergy with paclitaxel but not with 5-FU in SCC-25 cells, derived from oral squamous cell carcinomas. Mechanistically, the synergistic effect of MPA on 5-FU in MDA-MB-231 cells can be recapitulated by inhibiting the RNA polymerase-I activity and requires the expression of nucleostemin. This work reveals that the synergy between MPA and anti-proliferative agents is determined by cell type-dependent factors.

  13. PRISM/PRDM6, a Transcriptional Repressor That Promotes the Proliferative Gene Program in Smooth Muscle Cells

    OpenAIRE

    Davis, Christopher A.; Haberland, Michael; Arnold, Michael A.; Sutherland, Lillian B.; McDonald, Oliver G.; Richardson, James A.; Childs, Geoffrey; Harris, Stephen; Owens, Gary K.; Olson, Eric N.

    2006-01-01

    Smooth muscle cells (SMCs) display remarkable phenotypic diversity and plasticity and can readily switch between proliferative and differentiated states in response to extracellular cues. In an effort to identify novel transcriptional regulators of smooth muscle phenotypes, we compared the gene expression profiles of arterial and venous SMCs by microarray-based transcriptional profiling. Among numerous genes displaying distinct expression patterns in these two SMC types, we discovered an expr...

  14. Time-variant clustering model for understanding cell fate decisions.

    Science.gov (United States)

    Huang, Wei; Cao, Xiaoyi; Biase, Fernando H; Yu, Pengfei; Zhong, Sheng

    2014-11-01

    Both spatial characteristics and temporal features are often the subjects of concern in physical, social, and biological studies. This work tackles the clustering problems for time course data in which the cluster number and clustering structure change with respect to time, dubbed time-variant clustering. We developed a hierarchical model that simultaneously clusters the objects at every time point and describes the relationships of the clusters between time points. The hidden layer of this model is a generalized form of branching processes. A reversible-jump Markov Chain Monte Carlo method was implemented for model inference, and a feature selection procedure was developed. We applied this method to explore an open question in preimplantation embryonic development. Our analyses using single-cell gene expression data suggested that the earliest cell fate decision could start at the 4-cell stage in mice, earlier than the commonly thought 8- to 16-cell stage. These results together with independent experimental data from single-cell RNA-seq provided support against a prevailing hypothesis in mammalian development. PMID:25339442

  15. Nanomaterials for regulating cancer and stem cell fate

    Science.gov (United States)

    Shah, Birju P.

    The realm of nanomedicine has grown exponentially over the past few decades. However, there are several obstacles that need to be overcome, prior to the wide-spread clinical applications of these nanoparticles, such as (i) developing well-defined nanoparticles of varying size, morphology and composition to enable various clinical applications; (ii) overcome various physiological barriers encountered in order to deliver the therapeutics to the target location; and (iii) real-time monitoring of the nano-therapeutics within the human body for tracking their uptake, localization and effect. Hence, this dissertation focuses on developing multimodal nanotechnology-based approaches to overcome the above-mentioned challenges and thus enable regulation of cancer and stem cell fate. The initial part of this dissertation describes the development of multimodal magnetic core-shell nanoparticles (MCNPs), comprised of a highly magnetic core surrounded by a thin gold shell, thus combining magnetic and plasmonic properties. These nanoparticles were utilized for mainly two applications: (i) Magnetically-facilitated delivery of siRNA and plasmid DNA for effective stem cell differentiation and imaging and (ii) Combined hyperthermia and targeted delivery of a mitochondria-targeting peptide for enhancing apoptosis in cancer cells. The following part of this dissertation presents the generation of a multi-functional cyclodextrin-conjugated polymeric delivery platform (known as DexAMs), for co-delivery of anticancer drugs and siRNAs in a target-specific manner to brain tumor cells. This combined delivery of chemotherapeutics and siRNA resulted in a synergistic effect on the apoptosis of brain tumor cells, as compared to the individual treatments. The final part of this thesis presents development of stimuli-responsive uorescence resonance energy transfer (FRET)-based mesoporous silica nanoparticles for real-time monitoring of drug release in cells. The stimuli-responsive behavior of

  16. Cell fate reprogramming by control of intracellular network dynamics

    Science.gov (United States)

    Zanudo, Jorge G. T.; Albert, Reka

    Identifying control strategies for biological networks is paramount for practical applications that involve reprogramming a cell's fate, such as disease therapeutics and stem cell reprogramming. Although the topic of controlling the dynamics of a system has a long history in control theory, most of this work is not directly applicable to intracellular networks. Here we present a network control method that integrates the structural and functional information available for intracellular networks to predict control targets. Formulated in a logical dynamic scheme, our control method takes advantage of certain function-dependent network components and their relation to steady states in order to identify control targets, which are guaranteed to drive any initial state to the target state with 100% effectiveness and need to be applied only transiently for the system to reach and stay in the desired state. We illustrate our method's potential to find intervention targets for cancer treatment and cell differentiation by applying it to a leukemia signaling network and to the network controlling the differentiation of T cells. We find that the predicted control targets are effective in a broad dynamic framework. Moreover, several of the predicted interventions are supported by experiments. This work was supported by NSF Grant PHY 1205840.

  17. Generation of bivalent chromatin domains during cell fate decisions

    Directory of Open Access Journals (Sweden)

    De Gobbi Marco

    2011-06-01

    Full Text Available Abstract Background In self-renewing, pluripotent cells, bivalent chromatin modification is thought to silence (H3K27me3 lineage control genes while 'poising' (H3K4me3 them for subsequent activation during differentiation, implying an important role for epigenetic modification in directing cell fate decisions. However, rather than representing an equivalently balanced epigenetic mark, the patterns and levels of histone modifications at bivalent genes can vary widely and the criteria for identifying this chromatin signature are poorly defined. Results Here, we initially show how chromatin status alters during lineage commitment and differentiation at a single well characterised bivalent locus. In addition we have determined how chromatin modifications at this locus change with gene expression in both ensemble and single cell analyses. We also show, on a global scale, how mRNA expression may be reflected in the ratio of H3K4me3/H3K27me3. Conclusions While truly 'poised' bivalently modified genes may exist, the original hypothesis that all bivalent genes are epigenetically premarked for subsequent expression might be oversimplistic. In fact, from the data presented in the present work, it is equally possible that many genes that appear to be bivalent in pluripotent and multipotent cells may simply be stochastically expressed at low levels in the process of multilineage priming. Although both situations could be considered to be forms of 'poising', the underlying mechanisms and the associated implications are clearly different.

  18. Insulin Promotes Proliferative Vitality and Invasive Capability of Pancreatic Cancer Cells via Hypoxia-inducible Factor 1α Pathway

    Institute of Scientific and Technical Information of China (English)

    汪理; 周伟; 勾善淼; 王统玲; 刘涛; 王春友

    2010-01-01

    This study examined whether insulin-stimulated hypoxia-inducible factor 1α(HIF-1α) expression plays a crucial role in promoting the proliferative vitality and invasive capability in human pancreatic cancer cells.PANC-1 cells were divided into three groups:Control group,insulin group and insulin+YC-1(a pharmacological inhibitor of HIF-1α) group in terms of different treatments.Cells in the insulin group or insulin+YC-1 group were treated with insulin(0.1,1,10 and 100 nmol/L) alone or combined with 3-(5'-hydr...

  19. Mitophagy-driven mitochondrial rejuvenation regulates stem cell fate.

    Science.gov (United States)

    Vazquez-Martin, Alejandro; Van den Haute, Chris; Cufí, Sílvia; Corominas-Faja, Bruna; Cuyàs, Elisabet; Lopez-Bonet, Eugeni; Rodriguez-Gallego, Esther; Fernández-Arroyo, Salvador; Joven, Jorge; Baekelandt, Veerle; Menendez, Javier A

    2016-07-01

    Our understanding on how selective mitochondrial autophagy, or mitophagy, can sustain the archetypal properties of stem cells is incomplete. PTEN-induced putative kinase 1 (PINK1) plays a key role in the maintenance of mitochondrial morphology and function and in the selective degradation of damaged mitochondria by mitophagy. Here, using embryonic fibroblasts fromPINK1 gene-knockout (KO) mice, we evaluated whether mitophagy is a causal mechanism for the control of cell-fate plasticity and maintenance of pluripotency. Loss of PINK1-dependent mitophagy was sufficient to dramatically decrease the speed and efficiency of induced pluripotent stem cell (iPSC) reprogramming. Mitophagy-deficient iPSC colonies, which were characterized by a mixture of mature and immature mitochondria, seemed unstable, with a strong tendency to spontaneously differentiate and form heterogeneous populations of cells. Although mitophagy-deficient iPSC colonies normally expressed pluripotent markers, functional monitoring of cellular bioenergetics revealed an attenuated glycolysis in mitophagy-deficient iPSC cells. Targeted metabolomics showed a notable alteration in numerous glycolysis- and TCA-related metabolites in mitophagy-deficient iPSC cells, including a significant decrease in the intracellular levels of α-ketoglutarate -a key suppressor of the differentiation path in stem cells. Mitophagy-deficient iPSC colonies exhibited a notably reduced teratoma-initiating capacity, but fully retained their pluripotency and multi-germ layer differentiation capacity in vivo. PINK1-dependent mitophagy pathway is an important mitochondrial switch that determines the efficiency and quality of somatic reprogramming. Mitophagy-driven mitochondrial rejuvenation might contribute to the ability of iPSCs to suppress differentiation by directing bioenergetic transition and metabolome remodeling traits. These findings provide new insights into how mitophagy might influence the stem cell decisions to retain

  20. EBI2 augments Tfh cell fate by promoting interaction with IL-2-quenching dendritic cells.

    Science.gov (United States)

    Li, Jianhua; Lu, Erick; Yi, Tangsheng; Cyster, Jason G

    2016-05-01

    T follicular helper (Tfh) cells are a subset of T cells carrying the CD4 antigen; they are important in supporting plasma cell and germinal centre responses. The initial induction of Tfh cell properties occurs within the first few days after activation by antigen recognition on dendritic cells, although how dendritic cells promote this cell-fate decision is not fully understood. Moreover, although Tfh cells are uniquely defined by expression of the follicle-homing receptor CXCR5 (refs 1, 2), the guidance receptor promoting the earlier localization of activated T cells at the interface of the B-cell follicle and T zone has been unclear. Here we show that the G-protein-coupled receptor EBI2 (GPR183) and its ligand 7α,25-dihydroxycholesterol mediate positioning of activated CD4 T cells at the interface of the follicle and T zone. In this location they interact with activated dendritic cells and are exposed to Tfh-cell-promoting inducible co-stimulator (ICOS) ligand. Interleukin-2 (IL-2) is a cytokine that has multiple influences on T-cell fate, including negative regulation of Tfh cell differentiation. We demonstrate that activated dendritic cells in the outer T zone further augment Tfh cell differentiation by producing membrane and soluble forms of CD25, the IL-2 receptor α-chain, and quenching T-cell-derived IL-2. Mice lacking EBI2 in T cells or CD25 in dendritic cells have reduced Tfh cells and mount defective T-cell-dependent plasma cell and germinal centre responses. These findings demonstrate that distinct niches within the lymphoid organ T zone support distinct cell fate decisions, and they establish a function for dendritic-cell-derived CD25 in controlling IL-2 availability and T-cell differentiation. PMID:27147029

  1. Prolonged antigen presentation by immune complex-binding dendritic cells programs the proliferative capacity of memory CD8 T cells.

    Science.gov (United States)

    León, Beatriz; Ballesteros-Tato, André; Randall, Troy D; Lund, Frances E

    2014-07-28

    The commitment of naive CD8 T cells to effector or memory cell fates can occur after a single day of antigenic stimulation even though virus-derived antigens (Ags) are still presented by DCs long after acute infection is resolved. However, the effects of extended Ag presentation on CD8 T cells are undefined and the mechanisms that regulate prolonged Ag presentation are unknown. We showed that the sustained presentation of two different epitopes from influenza virus by DCs prevented the premature contraction of the primary virus-specific CD8 T cell response. Although prolonged Ag presentation did not alter the number of memory CD8 T cells that developed, it was essential for programming the capacity of these cells to proliferate, produce cytokines, and protect the host after secondary challenge. Importantly, prolonged Ag presentation by DCs was dependent on virus-specific, isotype-switched antibodies (Abs) that facilitated the capture and cross-presentation of viral Ags by FcγR-expressing DCs. Collectively, our results demonstrate that B cells and Abs can regulate the quality and functionality of a subset of antiviral CD8 T cell memory responses and do so by promoting sustained Ag presentation by DCs during the contraction phase of the primary T cell response. PMID:25002751

  2. Fate and degradation of petroleum hydrocarbons in stormwater bioretention cells

    Science.gov (United States)

    LeFevre, Gregory Hallett

    This dissertation describes the investigation of the fate of hydrocarbons in stormwater bioretention areas and those mechanisms that affect hydrocarbon fate in such systems. Seventy-five samples from 58 bioretention areas were collected and analyzed to measure total petroleum hydrocarbon (TPH) residual and biodegradation functional genes. TPH residual in bioretention areas was greater than background sites but low overall (<3 µg/kg), and well below either the TPH concentration of concern or the expected concentration, assuming no losses. Bioretention areas with deep-root vegetation contained significantly greater quantites of bacterial 16S rRNA genes and two functional genes involved in hydrocarbon biodegradation. Field soils were capable of mineralizing naphthalene, a polycyclic aromatic hydrocarbon (PAH) when incubated in the laboratory. In an additional laboratory investigation, a column study was initiated to comprehensively determine naphthalene fate in a simulated bioretention cell using a 14C-labeled tracer. Sorption to soil was the greatest sink of naphthalene in the columns, although biodegradation and vegetative uptake were also important loss mechanisms. Little leaching occurred following the first flush, and volatilization was insignificant. Significant enrichment of naphthalene degrading bacteria occurred over the course of the experiment as a result of naphthalene exposure. This was evident from enhanced naphthalene biodegradation kinetics (measured via batch tests), significant increases in naphthalene dioxygenase gene quantities, and a significant correlation observed between naphthalene residual and biodegradation functional genes. Vegetated columns outperformed the unplanted control column in terms of total naphthalene removal and biodegradation kinetics. As a result of these experiments, a final study focused on why planted systems outperform unplanted systems was conducted. Plant root exudates were harvested from hydroponic setups for three

  3. Modification of cell volume and proliferative capacity of Pseudokirchneriella subcapitata cells exposed to metal stress

    International Nuclear Information System (INIS)

    Highlights: •Metals induce morphological alterations on P. subcapitata. •Algal cell cycle consists: mother cell growth; cell division, with two nucleus divisions; release of four autospores. •Cu(II) and Cr(VI) arrest cell growth before the first nuclear division. •Cd(II) arrests cell growth after the second nuclear division but before the cytokinesis. •The approach used can be useful in the elucidation of different modes of action of pollutants. -- Abstract: The impact of metals (Cd, Cr, Cu and Zn) on growth, cell volume and cell division of the freshwater alga Pseudokirchneriella subcapitata exposed over a period of 72 h was investigated. The algal cells were exposed to three nominal concentrations of each metal: low (closed to 72 h-EC10 values), intermediate (closed to 72 h-EC50 values) and high (upper than 72 h-EC90 values). The exposure to low metal concentrations resulted in a decrease of cell volume. On the contrary, for the highest metal concentrations an increase of cell volume was observed; this effect was particularly notorious for Cd and less pronounced for Zn. Two behaviours were found when algal cells were exposed to intermediate concentrations of metals: Cu(II) and Cr(VI) induced a reduction of cell volume, while Cd(II) and Zn(II) provoked an opposite effect. The simultaneous nucleus staining and cell image analysis, allowed distinguishing three phases in P. subcapitata cell cycle: growth of mother cell; cell division, which includes two divisions of the nucleus; and, release of four autospores. The exposure of P. subcapitata cells to the highest metal concentrations resulted in the arrest of cell growth before the first nucleus division [for Cr(VI) and Cu(II)] or after the second nucleus division but before the cytokinesis (release of autospores) when exposed to Cd(II). The different impact of metals on algal cell volume and cell-cycle progression, suggests that different toxicity mechanisms underlie the action of different metals studied

  4. Modification of cell volume and proliferative capacity of Pseudokirchneriella subcapitata cells exposed to metal stress

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Manuela D. [Bioengineering Laboratory-CIETI, Chemical Engineering Department, ISEP-School of Engineering of Polytechnic Institute of Porto, Rua Dr António Bernardino de Almeida, 431, 4200-072 Porto (Portugal); IBB-Institute for Biotechnology and Bioengineering, Centre for Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Soares, Eduardo V., E-mail: evs@isep.ipp.pt [Bioengineering Laboratory-CIETI, Chemical Engineering Department, ISEP-School of Engineering of Polytechnic Institute of Porto, Rua Dr António Bernardino de Almeida, 431, 4200-072 Porto (Portugal); IBB-Institute for Biotechnology and Bioengineering, Centre for Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

    2014-02-15

    Highlights: •Metals induce morphological alterations on P. subcapitata. •Algal cell cycle consists: mother cell growth; cell division, with two nucleus divisions; release of four autospores. •Cu(II) and Cr(VI) arrest cell growth before the first nuclear division. •Cd(II) arrests cell growth after the second nuclear division but before the cytokinesis. •The approach used can be useful in the elucidation of different modes of action of pollutants. -- Abstract: The impact of metals (Cd, Cr, Cu and Zn) on growth, cell volume and cell division of the freshwater alga Pseudokirchneriella subcapitata exposed over a period of 72 h was investigated. The algal cells were exposed to three nominal concentrations of each metal: low (closed to 72 h-EC{sub 10} values), intermediate (closed to 72 h-EC{sub 50} values) and high (upper than 72 h-EC{sub 90} values). The exposure to low metal concentrations resulted in a decrease of cell volume. On the contrary, for the highest metal concentrations an increase of cell volume was observed; this effect was particularly notorious for Cd and less pronounced for Zn. Two behaviours were found when algal cells were exposed to intermediate concentrations of metals: Cu(II) and Cr(VI) induced a reduction of cell volume, while Cd(II) and Zn(II) provoked an opposite effect. The simultaneous nucleus staining and cell image analysis, allowed distinguishing three phases in P. subcapitata cell cycle: growth of mother cell; cell division, which includes two divisions of the nucleus; and, release of four autospores. The exposure of P. subcapitata cells to the highest metal concentrations resulted in the arrest of cell growth before the first nucleus division [for Cr(VI) and Cu(II)] or after the second nucleus division but before the cytokinesis (release of autospores) when exposed to Cd(II). The different impact of metals on algal cell volume and cell-cycle progression, suggests that different toxicity mechanisms underlie the action of

  5. Phytochemical Properties and Anti-Proliferative Activity of Olea europaea L. Leaf Extracts against Pancreatic Cancer Cells

    Directory of Open Access Journals (Sweden)

    Chloe D. Goldsmith

    2015-07-01

    Full Text Available Olea europaea L. leaves are an agricultural waste product with a high concentration of phenolic compounds; especially oleuropein. Oleuropein has been shown to exhibit anti-proliferative activity against a number of cancer types. However, they have not been tested against pancreatic cancer, the fifth leading cause of cancer related death in Western countries. Therefore, water, 50% ethanol and 50% methanol extracts of Corregiola and Frantoio variety Olea europaea L. leaves were investigated for their total phenolic compounds, total flavonoids and oleuropein content, antioxidant capacity and anti-proliferative activity against MiaPaCa-2 pancreatic cancer cells. The extracts only had slight differences in their phytochemical properties, and at 100 and 200 μg/mL, all decreased the viability of the pancreatic cancer cells relative to controls. At 50 μg/mL, the water extract from the Corregiola leaves exhibited the highest anti-proliferative activity with the effect possibly due to early eluting HPLC peaks. For this reason, olive leaf extracts warrant further investigation into their potential anti-pancreatic cancer benefits.

  6. β-catenin-driven binary cell fate decisions in animal development.

    Science.gov (United States)

    Bertrand, Vincent

    2016-01-01

    The Wnt/β-catenin pathway plays key roles during animal development. In several species, β-catenin is used in a reiterative manner to regulate cell fate diversification between daughter cells following division. This binary cell fate specification mechanism has been observed in animals that belong to very diverse phyla: the nematode Caenorhabditis elegans, the annelid Platynereis, and the ascidian Ciona. It may also play a role in the regulation of several stem cell lineages in vertebrates. While the molecular mechanism behind this binary cell fate switch is not fully understood, it appears that both secreted Wnt ligands and asymmetric cortical factors contribute to the generation of the difference in nuclear β-catenin levels between daughter cells. β-Catenin then cooperates with lineage specific transcription factors to induce the expression of novel sets of transcription factors at each round of divisions, thereby diversifying cell fate. For further resources related to this article, please visit the WIREs website. PMID:26952169

  7. The proliferative effects of asbestos-exposed peripheral blood mononuclear cells on mesothelial cells

    Science.gov (United States)

    MAKI, YUHO; NISHIMURA, YASUMITSU; TOYOOKA, SHINICHI; SOH, JUNICHI; TSUKUDA, KAZUNORI; SHIEN, KAZUHIKO; FURUKAWA, MASASHI; MURAOKA, TAKAYUKI; UENO, TSUYOSHI; TANAKA, NORIMITSU; YAMAMOTO, HIROMASA; ASANO, HIROAKI; MAEDA, MEGUMI; KUMAGAI-TAKEI, NAOKO; LEE, SUNI; MATSUZAKI, HIDENORI; OTSUKI, TAKEMI; MIYOSHI, SHINICHIRO

    2016-01-01

    Malignant mesothelioma (MM) is thought to arise from the direct effect of asbestos on mesothelial cells. However, MM takes a long time to develop following exposure to asbestos, which suggests that the effects of asbestos are complex. The present study examined the effects of asbestos exposure on the cell growth of MeT-5A human mesothelial cells via cytokines produced by immune cells. Peripheral blood mononuclear cells (PBMCs) were stimulated with antibodies against cluster of differentiation (CD)3 and CD28 upon exposure to the asbestos chrysotile A (CA) or crocidolite (CR); the growth of MeT-5A cells in media supplemented with PBMC culture supernatants was subsequently examined. MeT-5A cells exhibited an increase in proliferation when grown in supernatant from the 7-day PBMC culture exposed to CA or CR. Analysis of cytokine production demonstrated increased levels of granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-1α, IL-1β, IL-3, IL-5, IL-13 and IL-17A in supernatants. Individual administration of these cytokines, excluding G-CSF and GM-CSF, led to an increase in cell growth of MeT-5A, whereas this effect was not observed following the combined administration of these cytokines. The results indicate that cytokines secreted by immune cells upon exposure to asbestos cause an increase in the growth activity of mesothelial cells, suggesting that alterations in the production of cytokines by immune cells may contribute to tumorigenesis in individuals exposed to asbestos.

  8. Cellular Programming and Reprogramming: Sculpting Cell Fate for the Production of Dopamine Neurons for Cell Therapy

    Directory of Open Access Journals (Sweden)

    Julio C. Aguila

    2012-01-01

    success of clinical applications depends on our ability to steer pluripotent stem cells towards the right neuronal identity. In Parkinson disease, the loss of dopamine neurons is more pronounced in the ventrolateral population that projects to the sensorimotor striatum. Because synapses are highly specific, only neurons with this precise identity will contribute, upon transplantation, to the synaptic reconstruction of the dorsal striatum. Thus, understanding the developmental cell program of the mesostriatal dopamine neurons is critical for the identification of the extrinsic signals and cell-intrinsic factors that instruct and, ultimately, determine cell identity. Here, we review how extrinsic signals and transcription factors act together during development to shape midbrain cell fates. Further, we discuss how these same factors can be applied in vitro to induce, select, and reprogram cells to the mesostriatal dopamine fate.

  9. Ki-S1, a novel proliferative marker: flow cytometric assessment of staining in human breast carcinoma cells.

    OpenAIRE

    Camplejohn, R. S.; Brock, A.; Barnes, D. M.; Gillett, C; Raikundalia, B.; Kreipe, H.; Parwaresch, M R

    1993-01-01

    There is considerable interest in immunohistochemical markers of proliferation which are suitable for use on routinely fixed clinical material. The novel proliferation-associated antibody Ki-S1 shows promise in this respect. In this study we have: (i) defined the pattern of Ki-S1 labelling relative to the cell cycle phase; (ii) investigated the labelling pattern with Ki-S1 on a human breast cell line (ZR75) under varying proliferative conditions induced by serum deprivation and refeeding; (ii...

  10. Phorbol 12-myristate 13-acetate induces protein kinase ceta-specific proliferative response in astrocytic tumor cells.

    Science.gov (United States)

    Hussaini, I M; Karns, L R; Vinton, G; Carpenter, J E; Redpath, G T; Sando, J J; VandenBerg, S R

    2000-07-21

    Protein kinase C (PKC) activation has been implicated in cellular proliferation in neoplastic astrocytes. The roles for specific PKC isozymes in regulating this glial response, however, are not well understood. The aim of this study was to characterize the expression of PKC isozymes and the role of PKC-eta expression in regulating cellular proliferation in two well characterized astrocytic tumor cell lines (U-1242 MG and U-251 MG) with different properties of growth in cell culture. Both cell lines expressed an array of conventional (alpha, betaI, betaII, and gamma) and novel (theta and epsilon) PKC isozymes that can be activated by phorbol myristate acetate (PMA). Another novel PKC isozyme, PKC-eta, was only expressed by U-251 MG cells. In contrast, PKC-delta was readily detected in U-1242 MG cells but was present only at low levels in U-251 MG cells. PMA (100 nm) treatment for 24 h increased cell proliferation by over 2-fold in the U-251 MG cells, whereas it decreased the mitogenic response in the U-1242 MG cells by over 90%. When PKC-eta was stably transfected into U-1242 MG cells, PMA increased cell proliferation by 2.2-fold, similar to the response of U-251 MG cells. The cell proliferation induced by PMA in both the U-251 MG and U-1242-PKC-eta cells was blocked by the PKC inhibitor bisindolylmaleimide (0.5 micrometer) and the MEK inhibitor, PD 98059 (50 micrometer). Transient transfection of wild type U-251 with PKC-eta antisense oligonucleotide (1 micrometer) also blocked the PMA-induced increase in [(3)H]thymidine incorporation. The data demonstrate that two glioblastoma lines, with functionally distinct proliferative responses to PMA, express different novel PKC isozymes and that the differential expression of PKC-eta plays a determining role in the different proliferative capacity. PMID:10806212

  11. Curcumin conjugated with PLGA potentiates sustainability, anti-proliferative activity and apoptosis in human colon carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Bhargav N Waghela

    Full Text Available Curcumin, an ingredient of turmeric, exhibits a variety of biological activities such as anti-inflammatory, anti-atherosclerotic, anti-proliferative, anti-oxidant, anti-cancer and anti-metastatic. It is a highly pleiotropic molecule that inhibits cell proliferation and induces apoptosis in cancer cells. Despite its imperative biological activities, chemical instability, photo-instability and poor bioavailability limits its utilization as an effective therapeutic agent. Therefore, enhancing the bioavailability of curcumin may improve its therapeutic index for clinical setting. In the present study, we have conjugated curcumin with a biodegradable polymer Poly (D, L-lactic-co-glycolic acid and evaluated its apoptotic potential in human colon carcinoma cells (HCT 116. The results show that curcumin-PLGA conjugate efficiently inhibits cell proliferation and cell survival in human colon carcinoma cells as compared to native curcumin. Additionally, curcumin conjugated with PLGA shows improved cellular uptake and exhibits controlled release at physiological pH as compared to native curcumin. The curcumin-PLGA conjugate efficiently activates the cascade of caspases and promotes intrinsic apoptotic signaling. Thus, the results suggest that conjugation potentiates the sustainability, anti-proliferative and apoptotic activity of curcumin. This approach could be a promising strategy to improve the therapeutic index of cancer therapy.

  12. A single dividing cell population with imbalanced fate drives oesophageal tumour growth.

    Science.gov (United States)

    Frede, Julia; Greulich, Philip; Nagy, Tibor; Simons, Benjamin D; Jones, Philip H

    2016-09-01

    Understanding the cellular mechanisms of tumour growth is key for designing rational anticancer treatment. Here we used genetic lineage tracing to quantify cell behaviour during neoplastic transformation in a model of oesophageal carcinogenesis. We found that cell behaviour was convergent across premalignant tumours, which contained a single proliferating cell population. The rate of cell division was not significantly different in the lesions and the surrounding epithelium. However, dividing tumour cells had a uniform, small bias in cell fate so that, on average, slightly more dividing than non-dividing daughter cells were generated at each round of cell division. In invasive cancers induced by Kras(G12D) expression, dividing cell fate became more strongly biased towards producing dividing over non-dividing cells in a subset of clones. These observations argue that agents that restore the balance of cell fate may prove effective in checking tumour growth, whereas those targeting cycling cells may show little selectivity. PMID:27548914

  13. ¬Mesenchymal Stem Cell Fate: Applying Biomaterials for Control of Stem Cell Behaviour

    OpenAIRE

    Hilary Jane Anderson; Matthew John Dalby; Jugal eSahoo; Rein eUljin

    2016-01-01

    Mesenchymal Stem Cell Fate: Applying Biomaterials for Control of Stem Cell BehaviourHilary J Anderson1, Jugal Kishore Sahoo2, Rein V Ulijn2,3, Matthew J Dalby1*1 Centre for Cell Engineering, University of Glasgow, Glasgow, UK.2 Technology and Innovation centre, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK. 3 Advanced Science Research Centre (ASRC) and Hunter College, City University of New York, NY 10031, NY, USA. Correspondence:*Hilary Andersonh.anderson...

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

    International Nuclear Information System (INIS)

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

  15. Sox17-Mediated XEN Cell Conversion Identifies Dynamic Networks Controlling Cell-Fate Decisions in Embryo-Derived Stem Cells

    Directory of Open Access Journals (Sweden)

    Angela C.H. McDonald

    2014-10-01

    Full Text Available Little is known about the gene regulatory networks (GRNs distinguishing extraembryonic endoderm (ExEn stem (XEN cells from those that maintain the extensively characterized embryonic stem cell (ESC. An intriguing network candidate is Sox17, an essential transcription factor for XEN derivation and self-renewal. Here, we show that forced Sox17 expression drives ESCs toward ExEn, generating XEN cells that contribute to ExEn when placed back into early mouse embryos. Transient Sox17 expression is sufficient to drive this fate change during which time cells transit through distinct intermediate states prior to the generation of functional XEN-like cells. To orchestrate this conversion process, Sox17 acts in autoregulatory and feedforward network motifs, regulating dynamic GRNs directing cell fate. Sox17-mediated XEN conversion helps to explain the regulation of cell-fate changes and reveals GRNs regulating lineage decisions in the mouse embryo.

  16. Proliferative kinetics of the haematopoietic stem cells of the mouse after several weeks of reconvalescence of an irradiation attack

    International Nuclear Information System (INIS)

    The 125IDU(iodo-deoxyuridine) tracer-technique was applied for investigating proliferative kinetics. The intention was to reveal a possible persistent irradiation damage in the haematopoietic stem-cells of the mouse. The three following methodically differing arrangements were made: 1. 35 days after irradiation with 450 rad no difference is found between the measured turnover of incorporated 125IUD in the bone marrow and not irradiated mice. However, there is a splenic cell population which unambiguously transfers its activity slowlier. A dose-response relationship exists to a limited extent. 2. By four transplantations at different instants the donors were marked first, and then the turnover of the early haematopoietic precursor cells in the bone marrow was detected. It resulted that 35 days after irradiation with 450 rad the turnover takes place slightly slowlier than in not irradiated early precursor cells. Iodised water, which is administered before the tracer technique is applied, seems to have a stimulating effect, particularly on the turnover of irradiated stem cells; the marking with a specific activity of 2000 Ci/mol seems to have a slightly toxic effect. 3. A test was developed, by which the proliferation velocity of stem cells and their descendants is measured when there is a very high proliferation stimulus. Differing amounts of bone marrow cells are transfused to lethally irradiated receivers. Within the logarithmic phase of the 125IDU incorporation the relative cellular proliferation, originating in the stem cells being in the spleen, is determined for the interval between day 3 and day 5. It results very clearly that the descendants of those stem cells irradiated with 450 rad after a reconvalescence time of 35 days present a lower degree of rapid proliferative ability than the not irradiated cells. (orig./MG)

  17. Human mammary progenitor cell fate decisions are productsof interactions with combinatorial microenvironments

    DEFF Research Database (Denmark)

    LaBarge, Mark A.; Nelson, Celeste M.; Villadsen, René;

    2009-01-01

    factors, ECM, and other cells, as well as physical properties of the ECM. To understand regulation of fate decisions, therefore, would require a means of understanding carefully choreographed combinatorial interactions. Here we used microenvironment protein microarrays to functionally identify...

  18. Msx2 alters the timing of retinal ganglion cells fate commitment and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Shao-Yun, E-mail: jiangshaoyun@yahoo.com [School of Dentistry, Tianjin Medical University, 12 Qi Xiang Tai Street, Tianjin 300070 (China); Wang, Jian-Tao, E-mail: wangjiantao65@hotmail.com [Eye Center, Tianjin Medical University, 64 Tongan Road, Tianjin 300070 (China); Dohney Eye Institute, Keck School of Medicine, University of Southern California, 1355 San Pablo Street, DOH 314, Los Angeles, CA 90033 (United States)

    2010-05-14

    Timing of cell fate commitment determines distinct retinal cell types, which is believed to be controlled by a tightly coordinated regulatory program of proliferation, cell cycle exit and differentiation. Although homeobox protein Msx2 could induce apoptosis of optic vesicle, it is unclear whether Msx2 regulates differentiation and cell fate commitment of retinal progenitor cells (RPCs) to retinal ganglion cells (RGCs). In this study, we show that overexpression of Msx2 transiently suppressed the expression of Cyclin D1 and blocked cell proliferation. Meanwhile, overexpression of Msx2 delayed the expression of RGC-specific differentiation markers (Math5 and Brn3b), which showed that Msx2 could affect the timing of RGCs fate commitment and differentiation by delaying the timing of cell cycle exit of retinal progenitors. These results indicate Msx2 possesses dual regulatory functions in controlling cell cycle progression of retinal RPCs and timing of RGCs differentiation.

  19. Msx2 alters the timing of retinal ganglion cells fate commitment and differentiation

    International Nuclear Information System (INIS)

    Timing of cell fate commitment determines distinct retinal cell types, which is believed to be controlled by a tightly coordinated regulatory program of proliferation, cell cycle exit and differentiation. Although homeobox protein Msx2 could induce apoptosis of optic vesicle, it is unclear whether Msx2 regulates differentiation and cell fate commitment of retinal progenitor cells (RPCs) to retinal ganglion cells (RGCs). In this study, we show that overexpression of Msx2 transiently suppressed the expression of Cyclin D1 and blocked cell proliferation. Meanwhile, overexpression of Msx2 delayed the expression of RGC-specific differentiation markers (Math5 and Brn3b), which showed that Msx2 could affect the timing of RGCs fate commitment and differentiation by delaying the timing of cell cycle exit of retinal progenitors. These results indicate Msx2 possesses dual regulatory functions in controlling cell cycle progression of retinal RPCs and timing of RGCs differentiation.

  20. Ultra violet radiation-induced defects in accessory cell function in the human proliferative response to tetanus

    International Nuclear Information System (INIS)

    Ultraviolet B radiation (290-320 nm) has been shown to interfere with accessory cell function of human peripheral blood mononuclear cells in the generation of a proliferative response to tetanus. By altering the timing of irradiation of adherent cells and using short pulses of antigen, we have identified a minimum of two u.v. sensitive accessory cell functions. The first involves antigen presentation and is not readily reversible with time in culture after irradiation. The second is demonstrated by the ability of low doses of u.v. radiation given after the tetanus toxoid pulse to inhibit an event(s) occuring independent of antigen processing. Both occur within a range of doses which would penetrate to the vasculature of the skin of humans exposed to the sun or to phototherapy. (author)

  1. Tenascin-C in the extracellular matrix promotes the selection of highly proliferative and tubulogenesis-defective endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Tercia Rodrigues [Universidade do Estado do Rio de Janeiro (UERJ), Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biologia Celular, Laboratorio de Biologia da Celula Endotelial e da Angiogenese (LabAngio), Rio de Janeiro (Brazil); Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Carvalho da Fonseca, Anna Carolina [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Nunes, Sara Santana; Oliveira da Silva, Aline [Universidade do Estado do Rio de Janeiro (UERJ), Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biologia Celular, Laboratorio de Biologia da Celula Endotelial e da Angiogenese (LabAngio), Rio de Janeiro (Brazil); Dubois, Luiz Gustavo Feijo; Faria, Jane; Kahn, Suzana Assad [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Viana, Nathan Bessa [Universidade Federal do Rio de Janeiro, Laboratorio de Pincas Oticas, Coordenacao de Programas de Estudos Avancados, Instituto de Ciencias Biomedicas, Rio de Janeiro (Brazil); Universidade Federal do Rio de Janeiro, Instituto de Fisica, Rio de Janeiro (Brazil); Marcondes, Jorge [Universidade Federal do Rio de Janeiro, Hospital Universitario Clementino Fraga Filho, Servico de Neurocirurgia, Rio de Janeiro (Brazil); Legrand, Chantal [Institut Universitaire d' Hematologie, Universite Paris-Diderot, Paris 7, INSERM U553, Paris (France); Moura-Neto, Vivaldo [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); and others

    2011-09-10

    The extracellular matrix (ECM) contains important cues for tissue homeostasis and morphogenesis. The matricellular protein tenascin-C (TN-C) is overexpressed in remodeling tissues and cancer. In the present work, we studied the effect of different ECM-which exhibited a significant diversity in their TN-C content-in endothelial survival, proliferation and tubulogenic differentiation: autologous (endothelial) ECM devoid of TN-C, but bearing large amounts of FN; fibroblast ECM, bearing both high TN-C and FN contents; and finally, glioma-derived matrices, usually poor in FN, but very rich in TN-C. HUVECs initially adhered to the immobilized matrix produced by U373 MG glioma cells, but significantly detached and died by anoikis (50 to 80%) after 24 h, as compared with cells incubated with endothelial and fibroblast matrices. Surviving endothelial cells (20 to 50%) became up to 6-fold more proliferative and formed 74-97% less tube-like structures in vitro than cells grown on non-tumoral matrices. An antibody against the EGF-like repeats of tenascin-C (TN-C) partially rescued cells from the tubulogenic defect, indicating that this molecule is responsible for the selection of highly proliferative and tubulogenic defective endothelial cells. Interestingly, by using defined substrata, in conditions that mimic glioma and normal cell ECM composition, we observed that fibronectin (FN) modulates the TN-C-induced selection of endothelial cells. Our data show that TN-C is able to modulate endothelial branching morphogenesis in vitro and, since it is prevalent in matrices of injured and tumor tissues, also suggest a role for this protein in vascular morphogenesis, in these physiological contexts.

  2. Tenascin-C in the extracellular matrix promotes the selection of highly proliferative and tubulogenesis-defective endothelial cells

    International Nuclear Information System (INIS)

    The extracellular matrix (ECM) contains important cues for tissue homeostasis and morphogenesis. The matricellular protein tenascin-C (TN-C) is overexpressed in remodeling tissues and cancer. In the present work, we studied the effect of different ECM-which exhibited a significant diversity in their TN-C content-in endothelial survival, proliferation and tubulogenic differentiation: autologous (endothelial) ECM devoid of TN-C, but bearing large amounts of FN; fibroblast ECM, bearing both high TN-C and FN contents; and finally, glioma-derived matrices, usually poor in FN, but very rich in TN-C. HUVECs initially adhered to the immobilized matrix produced by U373 MG glioma cells, but significantly detached and died by anoikis (50 to 80%) after 24 h, as compared with cells incubated with endothelial and fibroblast matrices. Surviving endothelial cells (20 to 50%) became up to 6-fold more proliferative and formed 74-97% less tube-like structures in vitro than cells grown on non-tumoral matrices. An antibody against the EGF-like repeats of tenascin-C (TN-C) partially rescued cells from the tubulogenic defect, indicating that this molecule is responsible for the selection of highly proliferative and tubulogenic defective endothelial cells. Interestingly, by using defined substrata, in conditions that mimic glioma and normal cell ECM composition, we observed that fibronectin (FN) modulates the TN-C-induced selection of endothelial cells. Our data show that TN-C is able to modulate endothelial branching morphogenesis in vitro and, since it is prevalent in matrices of injured and tumor tissues, also suggest a role for this protein in vascular morphogenesis, in these physiological contexts.

  3. Human Induced Pluripotent Stem Cell-Derived Microvesicles Transmit RNAs and Proteins to Recipient Mature Heart Cells Modulating Cell Fate and Behavior.

    Science.gov (United States)

    Bobis-Wozowicz, Sylwia; Kmiotek, Katarzyna; Sekula, Malgorzata; Kedracka-Krok, Sylwia; Kamycka, Elzbieta; Adamiak, Marta; Jankowska, Urszula; Madetko-Talowska, Anna; Sarna, Michal; Bik-Multanowski, Miroslaw; Kolcz, Jacek; Boruczkowski, Dariusz; Madeja, Zbigniew; Dawn, Buddhadeb; Zuba-Surma, Ewa K

    2015-09-01

    Microvesicles (MVs) are membrane-enclosed cytoplasmic fragments released by normal and activated cells that have been described as important mediators of cell-to-cell communication. Although the ability of human induced pluripotent stem cells (hiPSCs) to participate in tissue repair is being increasingly recognized, the use of hiPSC-derived MVs (hiPSC-MVs) in this regard remains unknown. Accordingly, we investigated the ability of hiPSC-MVs to transfer bioactive molecules including mRNA, microRNA (miRNA), and proteins to mature target cells such as cardiac mesenchymal stromal cells (cMSCs), and we next analyzed effects of hiPSC-MVs on fate and behavior of such target cells. The results show that hiPSC-MVs derived from integration-free hiPSCs cultured under serum-free and feeder-free conditions are rich in mRNA, miRNA, and proteins originated from parent cells; however, the levels of expression vary between donor cells and MVs. Importantly, we found that transfer of hiPSC components by hiPSC-MVs impacted on transcriptome and proteomic profiles of target cells as well as exerted proliferative and protective effects on cMSCs, and enhanced their cardiac and endothelial differentiation potential. hiPSC-MVs also transferred exogenous transcripts from genetically modified hiPSCs that opens new perspectives for future strategies to enhance MV content. We conclude that hiPSC-MVs are effective vehicles for transferring iPSC attributes to adult somatic cells, and hiPSC-MV-mediated horizontal transfer of RNAs and proteins to injured tissues may be used for therapeutic tissue repair. In this study, for the first time, we propose a new concept of use of hiPSCs as a source of safe acellular bioactive derivatives for tissue regeneration. PMID:26031404

  4. Blastomeres show differential fate changes in 8-cell Xenopus laevis embryos that are rotated 90 degrees before first cleavage

    Science.gov (United States)

    Huang, S.; Johnson, K. E.; Wang, H. Z.

    1998-01-01

    To study the mechanisms of dorsal axis specification, the alteration in dorsal cell fate of cleavage stage blastomeres in axis-respecified Xenopus laevis embryos was investigated. Fertilized eggs were rotated 90 degrees with the sperm entry point up or down with respect to the gravitational field. At the 8-cell stage, blastomeres were injected with the lineage tracers, Texas Red- or FITC-Dextran Amines. The distribution of the labeled progeny was mapped at the tail-bud stages (stages 35-38) and compared with the fate map of an 8-cell embryo raised in a normal orientation. As in the normal embryos, each blastomere in the rotated embryos has a characteristic and predictable cell fate. After 90 degrees rotation the blastomeres in the 8-cell stage embryo roughly switched their position by 90 degrees, but the fate of the blastomeres did not simply show a 90 degrees switch appropriate for their new location. Four types of fate change were observed: (i) the normal fate of the blastomere is conserved with little change; (ii) the normal fate is completely changed and a new fate is adopted according to the blastomere's new position: (iii) the normal fate is completely changed, but the new fate is not appropriate for its new position; and (4) the blastomere partially changed its fate and the new fate is a combination of its original fate and a fate appropriate to its new location. According to the changed fates, the blastomeres that adopt dorsal fates were identified in rotated embryos. This identification of dorsal blastomeres provides basic important information for further study of dorsal signaling in Xenopus embryos.

  5. Merkel cell polyomavirus and human papilloma virus in proliferative skin lesions arising in patients treated with BRAF inhibitors.

    Science.gov (United States)

    Falchook, G S; Rady, P; Konopinski, J C; Busaidy, N; Hess, K; Hymes, S; Nguyen, H P; Prieto, V G; Bustinza-Linares, E; Lin, Q; Parkhurst, K L; Hong, D S; Sherman, S; Tyring, S K; Kurzrock, R

    2016-07-01

    The potential role of oncogenic viruses mediating development of proliferative skin lesions in patients treated with RAF inhibitors is poorly understood. The objective of this study was to investigate human papilloma virus (HPV) and Merkel cell polyomavirus (MCPyV) in skin lesions among patients treated with RAF inhibitors with the help of a case series describing prevalence of HPV, MCPyV, and RAS mutations in skin biopsies obtained from patients receiving RAF inhibitors and developing cutaneous lesions. HPV-DNA was amplified by PCR utilizing multiple nested primer systems designed for detection of a broad range of HPV types. MCPyV copy number determination with real time PCR technology was performed by a "Quantification of MCPyV, small t region" kit. Thirty-six patients were tested (squamous cell carcinoma (SCC) = 14; verruca vulgaris = 15; other = 11). Nine of 12 SCCs (75 %) and eight of 13 verruca vulgaris lesions (62 %) tested positive for MCPyV whereas none of the normal skin biopsies obtained from nine of these patients tested positive for MCPyV (p = 0.0007). HPV incidence in cutaneous SCCs was not different compared to normal skin (50 vs. 56 %, p = 0.86). The association between MCPyV and proliferative skin lesions after RAF inhibitor therapy merits further investigation. PMID:27098388

  6. Facile modification of gelatin-based microcarriers with multiporous surface and proliferative growth factors delivery to enhance cell growth

    International Nuclear Information System (INIS)

    The design of microcarriers plays an important role in the success of cell expansion. The present article provides a facile approach to modify the gelatin-based particles and investigates the feasibility of their acting as microcarriers for cell attachment and growth. Gelatin particles (150-320 μm) were modified by cryogenic treatment and lyophilization to develop the surface with the features of multiporous morphology and were incorporated with proliferative growth factors (bFGF) by adsorption during the post-preparation, which enables them to serve as microcarriers for cells amplification, together with the advantages of larger cell-surface contact area and capability of promoting cell propagation. The microstructure and release assay of the modified microcarriers demonstrated that the pores on surface were uniform and bFGF was released in a controlled manner. Through in vitro fibroblast culture, these features resulted in a prominent increase in the cell attachment rate and cell growth rate relative to the conditions without modification. Although the scanning electron microscopy and optical microscopy analysis results indicated that cells attached, spread, and proliferated on all the microcarriers, cell growth clearly showed a significant correlation with the multiporous structure of microcarriers, in particular on bFGF combined ones. These results validate our previous assumption that the facile modification could improve cell growth on the gelatin-based microcarriers obviously and the novel microcarriers may be a promising candidate in tissue engineering

  7. Facile modification of gelatin-based microcarriers with multiporous surface and proliferative growth factors delivery to enhance cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Huang Sha [Department of Oral Histology and Pathology, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Research and Development Center for Tissue Engineering, Fourth Military Medical University, Xi' an 710032 (China); Wang Yijuan [Key Laboratory for Macromolecular Science of Shaanxi Province, Shaanxi Normal University, Xi' an 710062 (China); Deng, Tianzheng [Research and Development Center for Tissue Engineering, Fourth Military Medical University, Xi' an 710032 (China); Department of Oral and Maxillofacial Surgery, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Jin Fang [Department of Orthodontics, School of Stomatology, Fourth Military Medical University, Xi' an, 710032 (China); Liu Shouxin [Key Laboratory for Macromolecular Science of Shaanxi Province, Shaanxi Normal University, Xi' an 710062 (China); Zhang Yongjie [Department of Oral Histology and Pathology, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Research and Development Center for Tissue Engineering, Fourth Military Medical University, Xi' an 710032 (China); Feng Feng [Research and Development Center for Tissue Engineering, Fourth Military Medical University, Xi' an 710032 (China); Department of Dermatology, Tangdu Hospital, Fourth Military Medical University, Xi' an 710038 (China); Jin Yan [Department of Oral Histology and Pathology, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Research and Development Center for Tissue Engineering, Fourth Military Medical University, Xi' an 710032 (China)], E-mail: yanjin@fmmu.edu.cn

    2008-07-28

    The design of microcarriers plays an important role in the success of cell expansion. The present article provides a facile approach to modify the gelatin-based particles and investigates the feasibility of their acting as microcarriers for cell attachment and growth. Gelatin particles (150-320 {mu}m) were modified by cryogenic treatment and lyophilization to develop the surface with the features of multiporous morphology and were incorporated with proliferative growth factors (bFGF) by adsorption during the post-preparation, which enables them to serve as microcarriers for cells amplification, together with the advantages of larger cell-surface contact area and capability of promoting cell propagation. The microstructure and release assay of the modified microcarriers demonstrated that the pores on surface were uniform and bFGF was released in a controlled manner. Through in vitro fibroblast culture, these features resulted in a prominent increase in the cell attachment rate and cell growth rate relative to the conditions without modification. Although the scanning electron microscopy and optical microscopy analysis results indicated that cells attached, spread, and proliferated on all the microcarriers, cell growth clearly showed a significant correlation with the multiporous structure of microcarriers, in particular on bFGF combined ones. These results validate our previous assumption that the facile modification could improve cell growth on the gelatin-based microcarriers obviously and the novel microcarriers may be a promising candidate in tissue engineering.

  8. Cell Fate and Differentiation of Bone Marrow Mesenchymal Stem Cells

    Science.gov (United States)

    Jimi, Eijiro

    2016-01-01

    Osteoblasts and bone marrow adipocytes originate from bone marrow mesenchymal stem cells (BMMSCs) and there appears to be a reciprocal relationship between adipogenesis and osteoblastogenesis. Alterations in the balance between adipogenesis and osteoblastogenesis in BMMSCs wherein adipogenesis is increased relative to osteoblastogenesis are associated with decreased bone quality and quantity. Several proteins have been reported to regulate this reciprocal relationship but the exact nature of the signals regulating the balance between osteoblast and adipocyte formation within the bone marrow space remains to be determined. In this review, we focus on the role of Transducin-Like Enhancer of Split 3 (TLE3), which was recently reported to regulate the balance between osteoblast and adipocyte formation from BMMSCs. We also discuss evidence implicating canonical Wnt signalling, which plays important roles in both adipogenesis and osteoblastogenesis, in regulating TLE3 expression. Currently, there is demand for new effective therapies that target the stimulation of osteoblast differentiation to enhance bone formation. We speculate that reducing TLE3 expression or activity in BMMSCs could be a useful approach towards increasing osteoblast numbers and reducing adipogenesis in the bone marrow environment. PMID:27298623

  9. Deubiquitylating Enzyme UBP64 Controls Cell Fate through Stabilization of the Transcriptional Repressor Tramtrack▿

    Science.gov (United States)

    Bajpe, Prashanth Kumar; van der Knaap, Jan A.; Demmers, Jeroen A. A.; Bezstarosti, Karel; Bassett, Andrew; van Beusekom, Heleen M. M.; Travers, Andrew A.; Verrijzer, C. Peter

    2008-01-01

    Protein ubiquitylation plays a central role in multiple signal transduction pathways. However, the substrate specificity and potential developmental roles of deubiquitylating enzymes remain poorly understood. Here, we show that the Drosophila ubiquitin protease UBP64 controls cell fate in the developing eye. UBP64 represses neuronal cell fate but promotes the formation of nonneuronal cone cells. Using a proteomics approach, we identified the transcriptional repressor Tramtrack (TTK) as a primary UBP64 substrate. In common with TTK, reduced UBP64 levels lead to a loss of cone cells, supernumerary photoreceptors, and mechanosensory bristle cells. Previously, it was demonstrated that the blockade of neuronal cell fate was relieved by SINA-dependent ubiquitylation and degradation of TTK. We found that UBP64 counteracts SINA function by deubiquitylating TTK, leading to its stabilization and thereby promoting a nonneuronal cell fate. Mass spectrometric mapping revealed that SINA ubiquitylates multiple sites dispersed throughout TTK, which are duly deubiquitylated by UBP64. This observation suggests that both E3 SINA and UBP64 use a scanning mechanism to (de)ubiquitylate TTK. We conclude that the balance of TTK ubiquitylation by SINA and deubiquitylation by UBP64 constitutes a specific posttranslational switch controlling cell fate. PMID:18160715

  10. Role of Geminin in cell fate determination of hematopoietic stem cells (HSCs).

    Science.gov (United States)

    Yasunaga, Shin'ichiro; Ohno, Yoshinori; Shirasu, Naoto; Zhang, Bo; Suzuki-Takedachi, Kyoko; Ohtsubo, Motoaki; Takihara, Yoshihiro

    2016-09-01

    Geminin exerts two distinct molecular roles. Geminin negatively regulates DNA replication licensing through the direct interaction with Cdt1 to prevent re-replication in proliferating cells. Geminin also regulates chromatin remodeling through the direct interaction with Brahma/Brg1 to maintain undifferentiated states of stem cells. We previously uncovered that Polycomb-group complex 1 and Hoxb4/Hoxa9, well-known intrinsic factors that are essential for maintaining the hematopoietic stem cell (HSC) activity, alternatively act as ubiquitin-proteasome systems for Geminin protein to reduce the protein expression level, and sustain the HSC activity. Thus, Geminin is presumed to play an important role in determining cell fate, i.e., turning on and off cellular quiescence and proliferation/differentiation, in HSCs. We recently generated recombinant cell-penetrating Geminin (CP-Geminin), enabling rapid incorporation and withdraw of Geminin protein in cells. CP-Geminin may be useful in regulating the cell cycle and chromatin configuration. In this article, we summarize current information on the molecular functions of Geminin and the regulatory system for Geminin protein expression, and argue for the molecular role of Geminin in cell fate determination of HSCs, and future perspective of a new technology for manipulating the activities of HSCs and cancer stem cells (CSCs). PMID:27422432

  11. Platycodin D from Platycodonis Radix enhances the anti-proliferative effects of doxorubicin on breast cancer MCF-7 and MDA-MB-231 cells

    OpenAIRE

    Tang, Zheng-Hai; Li, Ting; Gao, Hong-wei; Sun, Wen; Chen, Xiu-Ping; Wang, Yi-Tao; Lu, Jin-jian

    2014-01-01

    Background It has been demonstrated that platycodin D (PD) exhibits anti-cancer activities. This study aims to investigate the anti-proliferative effects of the combination of PD and doxorubicin (DOX) on human breast cancer cells (MCF-7 and MDA-MB-231 cells). Methods The anti-proliferative effects of different dosages of PD, DOX, and PD + DOX on MCF-7 and MDA-MB-231 cells were determined by the MTT assay. The 10 μM PD, 5 μM DOX, and 10 μM PD + 5 μM DOX induced-protein expression of apoptosis-...

  12. Proliferative and anti-proliferative effects of dietary levels of phytoestrogens in rat pituitary GH3/B6/F10 cells - the involvement of rapidly activated kinases and caspases

    Directory of Open Access Journals (Sweden)

    Watson Cheryl S

    2009-09-01

    Full Text Available Abstract Background Phytoestogens are a group of lipophillic plant compounds that can have estrogenic effects in animals; both tumorigenic and anti-tumorigenic effects have been reported. Prolactin-secreting adenomas are the most prevalent form of pituitary tumors in humans and have been linked to estrogen exposures. We examined the proliferative effects of phytoestrogens on a rat pituitary tumor cell line, GH3/B6/F10, originally subcloned from GH3 cells based on its ability to express high levels of the membrane estrogen receptor-α. Methods We measured the proliferative effects of these phytoestrogens using crystal violet staining, the activation of several mitogen-activated protein kinases (MAPKs and their downstream targets via a quantitative plate immunoassay, and caspase enzymatic activities. Results Four phytoestrogens (coumestrol, daidzein, genistein, and trans-resveratrol were studied over wide concentration ranges. Except trans-resveratrol, all phytoestrogens increased GH3/B6/F10 cell proliferation at some concentration relevant to dietary levels. All four phytoestrogens attenuated the proliferative effects of estradiol when administered simultaneously. All phytoestrogens elicited MAPK and downstream target activations, but with time course patterns that often differed from that of estradiol and each other. Using selective antagonists, we determined that MAPKs play a role in the ability of these phytoestrogens to elicit these responses. In addition, except for trans-resveratrol, a serum removal-induced extrinsic apoptotic pathway was blocked by these phytoestrogens. Conclusion Phytoestrogens can block physiological estrogen-induced tumor cell growth in vitro and can also stimulate growth at high dietary concentrations in the absence of endogenous estrogens; these actions are correlated with slightly different signaling response patterns. Consumption of these compounds should be considered in strategies to control endocrine tumor cell

  13. Formula G1: Cell cycle in the driver's seat of stem cell fate determination.

    Science.gov (United States)

    Julian, Lisa M; Carpenedo, Richard L; Rothberg, Janet L Manias; Stanford, William L

    2016-04-01

    Cell cycle dynamics has emerged as a key regulator of stem cell fate decisions. In particular, differentiation decisions are associated with the G1 phase, and recent evidence suggests that self-renewal is actively regulated outside of G1. The mechanisms underlying these phenomena are largely unknown, but direct control of gene regulatory programs by the cell cycle machinery is heavily implicated. A recent study sheds important mechanistic insight by demonstrating that in human embryonic stem cells (hESCs) the Cyclin-dependent kinase CDK2 controls a wide-spread epigenetic program that drives transcription at differentiation-related gene promoters specifically in G1. Here, we discuss this finding and explore whether similar mechanisms are likely to function in multipotent stem cells. The implications of this discovery toward our understanding of stem cell-related disease are discussed, and we postulate novel mechanisms that position the cell cycle as a regulator of cell fate gene networks at epigenetic, transcriptional and post-transcriptional levels. PMID:26857166

  14. Expression of p75NGFR, a Proliferative and Basal Cell Marker, in the Buccal Mucosa Epithelium during Re-epithelialization

    International Nuclear Information System (INIS)

    We investigated the expression of p75NGFR, a proliferative and basal cell marker, in the mouse buccal mucosa epithelium during wound healing in order to elucidate the role of epithelial stem cells. Epithelial defects were generated in the epithelium of the buccal mucosa of 6-week-old mice using CO2 laser irradiation. BrdU was immediately administered to mice following laser irradiation. They were then sacrificed after 1, 3, 7, and 14 days. Paraffin sections were prepared and the irradiated areas were analyzed using immunohistochemistry with anti-p75NGFR, BrdU, PCNA, and CK14 antibodies. During re-epithelialization, PCNA (–)/p75NGFR (+) cells extended to the wound, which then closed, whereas PCNA (+)/p75NGFR (+) cells were not observed at the edge of the wound. In addition, p75NGFR (–)/CK14 (+), which reflected the presence of post-mitotic differentiating cells, was observed in the supra-basal layers of the extended epithelium. BrdU (+)/p75NGFR (+), which reflected the presence of epithelial stem cells, was detected sparsely in buccal basal epithelial cells after healing, and disappeared after 7 days. These results suggest that p75NGFR (+) keratinocytes are localized in the basal layer, which contains oral epithelial stem cells, and retain the ability to proliferate in order to regenerate the buccal mucosal epithelium

  15. Cell Adhesion Geometry Regulates Non-Random DNA Segregation and Asymmetric Cell Fates in Mouse Skeletal Muscle Stem Cells

    OpenAIRE

    Siham Yennek; Mithila Burute; Manuel Théry; Shahragim Tajbakhsh

    2014-01-01

    Cells of several metazoan species have been shown to non-randomly segregate their DNA such that older template DNA strands segregate to one daughter cell. The mechanisms that regulate this asymmetry remain undefined. Determinants of cell fate are polarized during mitosis and partitioned asymmetrically as the spindle pole orients during cell division. Chromatids align along the pole axis; therefore, it is unclear whether extrinsic cues that determine spindle pole position also promote non-rand...

  16. Cell Adhesion Geometry Regulates Non-Random DNA Segregation and Asymmetric Cell Fates in Mouse Skeletal Muscle Stem Cells

    OpenAIRE

    Yennek, Siham; Burute, Mithila; Théry, Manuel; Tajbakhsh, Shahragim

    2014-01-01

    International audience Cells of several metazoan species have been shown to non-randomly segregate their DNA such that older template DNA strands segregate to one daughter cell. The mechanisms that regulate this asymmetry remain undefined. Determinants of cell fate are polarized during mitosis and partitioned asymmetrically as the spindle pole orients during cell division. Chromatids align along the pole axis; therefore, it is unclear whether extrinsic cues that determine spindle pole posi...

  17. Cell adhesion geometry regulates non-random DNA segregation and asymmetric cell fates in mouse skeletal muscle stem cells.

    OpenAIRE

    Yennek, Siham; Burute, Mithila; Théry, Manuel; Tajbakhsh, Shahragim

    2014-01-01

    International audience Cells of several metazoan species have been shown to non-randomly segregate their DNA such that older template DNA strands segregate to one daughter cell. The mechanisms that regulate this asymmetry remain undefined. Determinants of cell fate are polarized during mitosis and partitioned asymmetrically as the spindle pole orients during cell division. Chromatids align along the pole axis; therefore, it is unclear whether extrinsic cues that determine spindle pole posi...

  18. Cell adhesion geometry regulates non-random DNA segregation and asymmetric cell fates in mouse skeletal muscle stem cells

    OpenAIRE

    Yennek, Siham; Burute, Mithila; Thery, Manuel

    2014-01-01

    Cells of several metazoan species have been shown to non-randomly segregate their DNA such that older template DNA strands segregate to one daughter cell. The mechanisms that regulate this asymmetry remain undefined. Determinants of cell fate are polarized during mitosis and partitioned asymmetrically as the spindle pole orients during cell division. Chromatids align along the pole axis; therefore, it is unclear whether extrinsic cues that determine spindle pole position also promote non-rand...

  19. Stem cell decisions: a twist of fate or a niche market?

    Science.gov (United States)

    Januschke, Jens; Näthke, Inke

    2014-10-01

    Establishing and maintaining cell fate in the right place at the right time is a key requirement for normal tissue maintenance. Stem cells are at the core of this process. Understanding how stem cells balance self-renewal and production of differentiating cells is key for understanding the defects that underpin many diseases. Both, external cues from the environment and cell intrinsic mechanisms can control the outcome of stem cell division. The role of the orientation of stem cell division has emerged as an important mechanism for specifying cell fate decisions. Although, the alignment of cell divisions can dependent on spatial cues from the environment, maintaining stemness is not always linked to positioning of stem cells in a particular microenvironment or `niche'. Alternate mechanisms that could contribute to cellular memory include differential segregation of centrosomes in asymmetrically dividing cells. PMID:24613913

  20. Autocrine/paracrine proliferative effect of ovarian GH and IGF-I in chicken granulosa cell cultures.

    Science.gov (United States)

    Ahumada-Solórzano, S Marisela; Martínez-Moreno, Carlos G; Carranza, Martha; Ávila-Mendoza, José; Luna-Acosta, José Luis; Harvey, Steve; Luna, Maricela; Arámburo, Carlos

    2016-08-01

    It is known that growth hormone (GH) and its receptor (GHR) are expressed in granulosa cells (GC) and thecal cells during the follicular development in the hen ovary, which suggests GH is involved in autocrine/paracrine actions in the female reproductive system. In this work, we show that the knockdown of local ovarian GH with a specific cGH siRNA in GC cultures significantly decreased both cGH mRNA expression and GH secretion to the media, and also reduced their proliferative rate. Thus, we analyzed the effect of ovarian GH and recombinant chicken GH (rcGH) on the proliferation of pre-hierarchical GCs in primary cultures. Incubation of GCs with either rcGH or conditioned media, containing predominantly a 15-kDa GH isoform, showed that both significantly increased proliferation as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, proliferating cell nuclear antigen (PCNA) quantification and ((3)H)-thymidine incorporation ((3)H-T) assays in a dose response fashion. Both, locally produced GH and rcGH also induced the phosphorylation of Erk1/2 in GC cultures. Furthermore, GH increased IGF-I synthesis and its release into the GC culture incubation media. These results suggest that GH may act through local IGF-I to induce GC proliferation, since IGF-I immunoneutralization completely abolished the GH-induced proliferative effect. These data suggest that GH and IGF-I may play a role as autocrine/paracrine regulators during the follicular development in the hen ovary at the pre-hierarchical stage. PMID:27174747

  1. Mammalian aPKC/Par polarity complex mediated regulation of epithelial division orientation and cell fate

    International Nuclear Information System (INIS)

    Oriented cell division is a key regulator of tissue architecture and crucial for morphogenesis and homeostasis. Balanced regulation of proliferation and differentiation is an essential property of tissues not only to drive morphogenesis but also to maintain and restore homeostasis. In many tissues orientation of cell division is coupled to the regulation of differentiation producing daughters with similar (symmetric cell division, SCD) or differential fate (asymmetric cell division, ACD). This allows the organism to generate cell lineage diversity from a small pool of stem and progenitor cells. Division orientation and/or the ratio of ACD/SCD need to be tightly controlled. Loss of orientation or an altered ratio can promote overgrowth, alter tissue architecture and induce aberrant differentiation, and have been linked to morphogenetic diseases, cancer and aging. A key requirement for oriented division is the presence of a polarity axis, which can be established through cell intrinsic and/or extrinsic signals. Polarity proteins translate such internal and external cues to drive polarization. In this review we will focus on the role of the polarity complex aPKC/Par3/Par6 in the regulation of division orientation and cell fate in different mammalian epithelia. We will compare the conserved function of this complex in mitotic spindle orientation and distribution of cell fate determinants and highlight common and differential mechanisms in which this complex is used by tissues to adapt division orientation and cell fate to the specific properties of the epithelium

  2. Mammalian aPKC/Par polarity complex mediated regulation of epithelial division orientation and cell fate

    Energy Technology Data Exchange (ETDEWEB)

    Vorhagen, Susanne; Niessen, Carien M., E-mail: carien.niessen@uni-koeln.de

    2014-11-01

    Oriented cell division is a key regulator of tissue architecture and crucial for morphogenesis and homeostasis. Balanced regulation of proliferation and differentiation is an essential property of tissues not only to drive morphogenesis but also to maintain and restore homeostasis. In many tissues orientation of cell division is coupled to the regulation of differentiation producing daughters with similar (symmetric cell division, SCD) or differential fate (asymmetric cell division, ACD). This allows the organism to generate cell lineage diversity from a small pool of stem and progenitor cells. Division orientation and/or the ratio of ACD/SCD need to be tightly controlled. Loss of orientation or an altered ratio can promote overgrowth, alter tissue architecture and induce aberrant differentiation, and have been linked to morphogenetic diseases, cancer and aging. A key requirement for oriented division is the presence of a polarity axis, which can be established through cell intrinsic and/or extrinsic signals. Polarity proteins translate such internal and external cues to drive polarization. In this review we will focus on the role of the polarity complex aPKC/Par3/Par6 in the regulation of division orientation and cell fate in different mammalian epithelia. We will compare the conserved function of this complex in mitotic spindle orientation and distribution of cell fate determinants and highlight common and differential mechanisms in which this complex is used by tissues to adapt division orientation and cell fate to the specific properties of the epithelium.

  3. Prolonged effect of fluid flow stress on the proliferative activity of mesothelial cells after abrupt discontinuation of fluid streaming

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, Shigehisa, E-mail: aokis@cc.saga-u.ac.jp [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan); Ikeda, Satoshi [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan); Takezawa, Toshiaki [Transgenic Animal Research Center, National Institute of Agrobiological Sciences, Ibaraki (Japan); Kishi, Tomoya [Department of Internal Medicine, Saga University, Saga (Japan); Makino, Junichi [Makino Clinic, Saga (Japan); Uchihashi, Kazuyoshi; Matsunobu, Aki [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan); Noguchi, Mitsuru [Department of Urology, Faculty of Medicine, Saga University, Saga (Japan); Sugihara, Hajime [Department of Physical Therapy, International University of Health and Welfare, Fukuoka (Japan); Toda, Shuji [Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga (Japan)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer Late-onset peritoneal fibrosis leading to EPS remains to be elucidated. Black-Right-Pointing-Pointer Fluid streaming is a potent factor for peritoneal fibrosis in PD. Black-Right-Pointing-Pointer We focused on the prolonged effect of fluid streaming on mesothelial cell kinetics. Black-Right-Pointing-Pointer A history of fluid streaming exposure promoted mesothelial proliferative activity. Black-Right-Pointing-Pointer We have thus identified a potent new factor for late-onset peritoneal fibrosis. -- Abstract: Encapsulating peritoneal sclerosis (EPS) often develops after transfer to hemodialysis and transplantation. Both termination of peritoneal dialysis (PD) and transplantation-related factors are risks implicated in post-PD development of EPS, but the precise mechanism of this late-onset peritoneal fibrosis remains to be elucidated. We previously demonstrated that fluid flow stress induced mesothelial proliferation and epithelial-mesenchymal transition via mitogen-activated protein kinase (MAPK) signaling. Therefore, we speculated that the prolonged bioactive effect of fluid flow stress may affect mesothelial cell kinetics after cessation of fluid streaming. To investigate how long mesothelial cells stay under the bioactive effect brought on by fluid flow stress after removal of the stress, we initially cultured mesothelial cells under fluid flow stress and then cultured the cells under static conditions. Mesothelial cells exposed to fluid flow stress for a certain time showed significantly high proliferative activity compared with static conditions after stoppage of fluid streaming. The expression levels of protein phosphatase 2A, which dephosphorylates MAPK, in mesothelial cells changed with time and showed a biphasic pattern that was dependent on the duration of exposure to fluid flow stress. There were no differences in the fluid flow stress-related bioactive effects on mesothelial cells once a certain time had passed

  4. A blueprint for engineering cell fate: current technologies to reprogram cell identity

    Institute of Scientific and Technical Information of China (English)

    Samantha A Morris; George Q Daley

    2013-01-01

    Human diseases such as heart failure,diabetes,neurodegenerative disorders,and many others result from the deficiency or dysfunction of critical cell types.Strategies for therapeutic tissue repair or regeneration require the in vitro manufacture of clinically relevant quantities of defined cell types.In addition to transplantation therapy,the generation of otherwise inaccessible cells also permits disease modeling,toxicology testing and drug discovery in vitro.In this review,we discuss current strategies to manipulate the identity of abundant and accessible cells by differentiation from an induced pluripotent state or direct conversion between differentiated states.We contrast these approaches with recent advances employing partial reprogramming to facilitate lineage switching,and discuss the mechanisms underlying the engineering of cell fate.Finally,we address the current limitations of the field and how the resulting cell types can be assessed to ensure the production of medically relevant populations.

  5. Two new oleanane-type triterpenoids from Platycodi Radix and anti-proliferative activity in HSC-T6 cells.

    Science.gov (United States)

    Zhan, Qin; Zhang, Feng; Sun, Lianna; Wu, Zhijun; Chen, Wansheng

    2012-01-01

    Two new oleanane-type triterpenoids, named platycodonoids A and B (1, 2), together with five known saponins, including platycodin D (3), deapioplatycodin D (4), 3-O-β-D-glucopyranosyl polygalacic acid (5), 3-O-β-D-glucopyranosyl platycodigenin (6) and polygalacin D (7), were isolated from the roots of Platycodon grandiflorum. On the basis of spectral data and chemical evidence, the structures of the new compounds were elucidated as 2β,3β,23,24-tetrahydroxy-28-nor-olean-12-en-16-one (1) and 2β,3β,23,24- tetrahydroxy-28-nor-olean-12-en-16-one-3-O-β-D-glucopyranoside (2). Compounds 1-7 were evaluated for their in vitro anti-proliferative activity against the HSC-T6 cell line. PMID:23519261

  6. Two New Oleanane-Type Triterpenoids from Platycodi Radix and Anti-proliferative Activity in HSC-T6 Cells

    Directory of Open Access Journals (Sweden)

    Wansheng Chen

    2012-12-01

    Full Text Available Two new oleanane-type triterpenoids, named platycodonoids A and B (1, 2, together with five known saponins, including platycodin D (3, deapioplatycodin D (4, 3-O-β-D-glucopyranosyl polygalacic acid (5, 3-O-β-D-glucopyranosyl platycodigenin (6 and polygalacin D (7, were isolated from the roots of Platycodon grandiflorum. On the basis of spectral data and chemical evidence, the structures of the new compounds were elucidated as 2β,3β,23,24-tetrahydroxy-28-nor-olean-12-en-16-one (1 and 2β,3β,23,24- tetrahydroxy-28-nor-olean-12-en-16-one-3-O-β-D-glucopyranoside (2. Compounds 1–7 were evaluated for their in vitro anti-proliferative activity against the HSC-T6 cell line.

  7. Identification of novel genes involved in the commitment of endodermal cells to the thymic epithelial cell fate

    OpenAIRE

    Mathieu, Yves D.

    2006-01-01

    The thymus provides the microenvironment for the maturation and selection of the majority of peripheral T cells. Endodermal cells of the ventral aspect of the third pharyngeal pouch (3rdpp) at 10.5 days of mouse gestation (E10.5) adopt a thymic epithelial cell fate while cells of the dorsal part of the 3rdpp give rise to the parathyroid glands. To identify novel genes potentially involved in the commitment of endodermal cells to the thymic epithelial cell fate, the transcriptome o...

  8. Evaluation of the proliferative activity of immunocompetent cells in the jejunal and iliac lymph nodes of prepubertal female wild boars diagnosed with mixed mycotoxicosis

    Directory of Open Access Journals (Sweden)

    Zielonka Łukasz

    2015-06-01

    Full Text Available The study evaluated the proliferative activity of immunocompetent cells in the jejunal and iliac lymph nodes of prepubertal female wild boars exposed to deoxynivalenol and zearalenone in naturally contaminated feed. The evaluation was performed with the use of the MTT assay and 2 mitogens: lipopolysaccharide (LPS and concanavalin A. Intensified proliferative processes in T and B lymphocytes were revealed. The mitogenic activity of LPS was more expressed in the lymphocytes of both iliac and jejunal lymph nodes in comparison with the control group. Proliferative activity was higher in iliac lymph nodes than in jejunal lymph nodes. A reverse trend was observed in the percentage of live cells, which was higher in jejunal lymph nodes during the evaluation of lymphocyte proliferation.

  9. ANTI-PROLIFERATIVE ACTIVITY OF TINOSPORA CORDIFOLIA DETERMINED BY CELL COUNT AND TRYPAN BLUE DYE EXCLUSION METHOD IN MCF-7 CELLS

    Directory of Open Access Journals (Sweden)

    Sakthi Priya M*, KV Venkateswaran, LN Mathuram, M ParthibanT and Vijayanand

    2013-04-01

    Full Text Available An in-vitro study was performed in mammary tumor cell line MCF-7 to find out the antiproliferative activity of aqueous and hydro-alcoholic extracts of Guduchi Tinospora cordifolia, each at three different doses viz., 200µg/ml, 400µg/ml and 600µg/ml. Their effects on the proliferation of cells were analyzed by cell count assay and cell viability was detected by using trypan blue dye exclusion method. Both of the extracts produced significant decrease in cell count and cell viability, with maximum effect being noticed at the dose level of 600µg/ml. This  result suggest that aqueous and hydro-alcoholic extracts of Tinospora cordifolia could reduce cell count and  cell viability in MCF-7 cell line and act as effective anti-proliferative agent in mammary tumor.

  10. DEPENDENCE OF STEM CELL FATE IN ARABIDOPSIS ON A FEEDBACK LOOP REGULATED BY CLV3 ACTIVITY

    Science.gov (United States)

    The fate of stem cells in plant meristems is governed by directional signalling systems that are regulated by negative feedback. In Arabidopsis, the CLAVATA (CLV) genes encode the essential components of a negative, stem cell restricting pathway. We have used transgenic plants over-expressing CLV3 t...

  11. Determining the fate of fluorescent quantum dots on surface of engineered budding S. cerevisiae cell molecular landscape

    OpenAIRE

    Chouhan, Raghuraj Singh; Qureshi, Anjum; Kolkar Mohammed, Javed Hussain Niazi

    2015-01-01

    In this study, we surface engineered living S. cerevisiae cells by decorating quantum dots (QDs) and traced the fate of QDs on molecular landscape of single mother cell through several generation times (progeny cells). The fate of QDs on cell-surface was tracked through the cellular division events using confocal microscopy and fluorescence emission profiles. The extent of cell-surface QDs distribution among the offspring was determined as the mother cell divides into daughter cells. Fluoresc...

  12. Lactobacillus casei Exerts Anti-Proliferative Effects Accompanied by Apoptotic Cell Death and Up-Regulation of TRAIL in Colon Carcinoma Cells

    Science.gov (United States)

    Santarmaki, Valentina; Aindelis, Georgios; Tompoulidou, Evgenia; Lamprianidou, Eleftheria E.; Saxami, Georgia; Ypsilantis, Petros; Lampri, Evangeli S.; Simopoulos, Constantinos; Kotsianidis, Ioannis; Galanis, Alex; Kourkoutas, Yiannis; Dimitrellou, Dimitra; Chlichlia, Katerina

    2016-01-01

    Probiotic microorganisms such as lactic acid bacteria (LAB) exert a number of strain-specific health-promoting activities attributed to their immunomodulatory, anti-inflammatory and anti-carcinogenic properties. Despite recent attention, our understanding of the biological processes involved in the beneficial effects of LAB strains is still limited. To this end, the present study investigated the growth-inhibitory effects of Lactobacillus casei ATCC 393 against experimental colon cancer. Administration of live Lactobacillus casei (as well as bacterial components thereof) on murine (CT26) and human (HT29) colon carcinoma cell lines raised a significant concentration- and time-dependent anti-proliferative effect, determined by cell viability assays. Specifically, a dramatic decrease in viability of colon cancer cells co-incubated with 109 CFU/mL L. casei for 24 hours was detected (78% for HT29 and 52% for CT26 cells). In addition, live L. casei induced apoptotic cell death in both cell lines as revealed by annexin V and propidium iodide staining. The significance of the in vitro anti-proliferative effects was further confirmed in an experimental tumor model. Oral daily administration of 109 CFU live L. casei for 13 days significantly inhibited in vivo growth of colon carcinoma cells, resulting in approximately 80% reduction in tumor volume of treated mice. Tumor growth inhibition was accompanied by L. casei-driven up-regulation of the TNF-related apoptosis-inducing ligand TRAIL and down-regulation of Survivin. Taken together, these findings provide evidence for beneficial tumor-inhibitory, anti-proliferative and pro-apoptotic effects driven by this probiotic LAB strain. PMID:26849051

  13. Lactobacillus casei Exerts Anti-Proliferative Effects Accompanied by Apoptotic Cell Death and Up-Regulation of TRAIL in Colon Carcinoma Cells.

    Directory of Open Access Journals (Sweden)

    Angeliki Tiptiri-Kourpeti

    Full Text Available Probiotic microorganisms such as lactic acid bacteria (LAB exert a number of strain-specific health-promoting activities attributed to their immunomodulatory, anti-inflammatory and anti-carcinogenic properties. Despite recent attention, our understanding of the biological processes involved in the beneficial effects of LAB strains is still limited. To this end, the present study investigated the growth-inhibitory effects of Lactobacillus casei ATCC 393 against experimental colon cancer. Administration of live Lactobacillus casei (as well as bacterial components thereof on murine (CT26 and human (HT29 colon carcinoma cell lines raised a significant concentration- and time-dependent anti-proliferative effect, determined by cell viability assays. Specifically, a dramatic decrease in viability of colon cancer cells co-incubated with 10(9 CFU/mL L. casei for 24 hours was detected (78% for HT29 and 52% for CT26 cells. In addition, live L. casei induced apoptotic cell death in both cell lines as revealed by annexin V and propidium iodide staining. The significance of the in vitro anti-proliferative effects was further confirmed in an experimental tumor model. Oral daily administration of 10(9 CFU live L. casei for 13 days significantly inhibited in vivo growth of colon carcinoma cells, resulting in approximately 80% reduction in tumor volume of treated mice. Tumor growth inhibition was accompanied by L. casei-driven up-regulation of the TNF-related apoptosis-inducing ligand TRAIL and down-regulation of Survivin. Taken together, these findings provide evidence for beneficial tumor-inhibitory, anti-proliferative and pro-apoptotic effects driven by this probiotic LAB strain.

  14. Post-proliferative immature radial glial cells female-specifically express aromatase in the medaka optic tectum.

    Directory of Open Access Journals (Sweden)

    Akio Takeuchi

    Full Text Available Aromatase, the key enzyme responsible for estrogen biosynthesis, is present in the brain of all vertebrates. Much evidence has accumulated that aromatase is highly and exclusively expressed in proliferating mature radial glial cells in the brain of teleost fish even in adulthood, unlike in other vertebrates. However, the physiological significance of this expression remains unknown. We recently found that aromatase is female-specifically expressed in the optic tectum of adult medaka fish. In the present study, we demonstrated that, contrary to the accepted view of the teleost brain, female-specific aromatase-expressing cells in the medaka optic tectum represent a transient subset of post-proliferative immature radial glial cells in the neural stem cell lineage. This finding led us to hypothesize that female-specific aromatase expression and consequent estrogen production causes some sex difference in the life cycle of tectal cells. As expected, the female tectum exhibited higher expression of genes indicative of cell proliferation and radial glial maturation and lower expression of an anti-apoptotic gene than did the male tectum, suggesting a female-biased acceleration of the cell life cycle. Complicating the interpretation of this result, however, is the additional observation that estrogen administration masculinized the expression of these genes in the optic tectum, while simultaneously stimulating aromatase expression. Taken together, these results provide evidence that a unique subpopulation of neural stem cells female-specifically express aromatase in the optic tectum and suggest that this aromatase expression and resultant estrogen synthesis have an impact on the life cycle of tectal cells, whether stimulatory or inhibitory.

  15. Expression Profile of Apoptotic Mediators and Proliferative Markers in Oral Squamous Cell Carcinoma

    International Nuclear Information System (INIS)

    Oral squamous cell carcinoma (OSCC) represents a major health problem worldwide. It is therefore essential to develop a deeper understanding of its biology. Beside the recent hypothesis of cancer stem cells, the consideration of its cell death and cell proliferation has emerged as important diagnostic and prognostic tools. Purpose of the Study: Detection of the proportion of cell loss monitored by apoptosis-related genes, p53, p21 and Bcl2, and their relationship to the pathological proliferation parameter, PCNA in OSCC. Furthermore, discussion of the hypothesis of cancer stem cell biology in OSCC would be anticipated. Material and Methods: Archival 35 tissue embedded paraffin blocks, that were previously diagnosed as well to moderately differentiated OSCC, were immunohistochemically stained using a panel of antibodies including apoptotic mediators, p53, p21, Bcl2, and proliferation marker, PCNA. Immuno expression was scored using a semiquantitative scale and statistically analyzed. Results: The clinico-pathological data revealed that mean age was 46.9±8.2 and the tongue was the most affected site, followed by the palate then the floor of the mouth. There was no significant difference between metastasizing and non-metastasizing patients regarding age or gender (p=0.174, 0.404, respectively). On the other hand, variable profile patterns of the investigated indicators existed, where PCNA positively immunostaining cells was 100% while P21 recorded the higher percentage of negatively immunoreactive cells (42.9%). A common trait for the studied cell cycle indicators was that the basal and supra basal epithelial cells as well as the peripheral cells of the invading nests were the harbor of immunoreactivity. Meanwhile, Pca immuno positivity was revealed in all epithelial layers plus stromal cells. Conclusions: Assessment of the studied cell cycle regulators may be valuable to judge tumorigenesis of Osac. Furthermore, deregulation of cell cycle control might aid in the

  16. Sigma factors, asymmetry, and the determination of cell fate in Bacillus subtilis.

    OpenAIRE

    Lewis, P J; Partridge, S R; Errington, J

    1994-01-01

    Soon after the initiation of sporulation, Bacillus subtilis divides asymmetrically to produce sister cells that have very different developmental fates. Recently, it has been proposed that the differential gene expression which begins soon after this division is due to cell-specific activation of the transcription factors sigma F and sigma E in the prespore and the mother cell, respectively. We describe the use of a method for the localization of gene expression in individual sporulating cell...

  17. Differential T Cell Function and Fate in Lymph Node and Nonlymphoid Tissues

    OpenAIRE

    Harris, N. L.; Watt, V; Ronchese, F.; Le Gros, G.

    2002-01-01

    The functions and fate of antigen-experienced T cells isolated from lymph node or nonlymphoid tissues were analyzed in a system involving adoptive transfer of in vitro-activated T cells into mice. Activated T cells present in the lymph nodes could be stimulated by antigen to divide, produce effector cytokines, and migrate to peripheral tissues. By contrast, activated T cells that had migrated into nonlymphoid tissues (lung and airway) produced substantial effector cytokines upon antigen chall...

  18. An emerging molecular mechanism for the neural vs mesodermal cell fate decision

    Institute of Scientific and Technical Information of China (English)

    Roman A Li; Kate G Storey

    2011-01-01

    @@ Understanding how primary cell fates are established and maintained in the vertebrate embryo provides important insights that inform directed in vitro differentiation of embryonic stem cells or adult cells that have undergone induced pluripotency.Neural differentiation is of particular interest as new neural cells may contribute to therapeutic approaches to nervous system injury and diseases and provide in vitro disease models for small molecule screening and for determining personalized drug treatments.

  19. Role of VDR in anti-proliferative effects of calcitriol in tumor-derived endothelial cells and tumor angiogenesis in vivo

    OpenAIRE

    Chung, Ivy; Han, Guangzhou; Seshadri, Mukund; Gillard, Bryan M.; Yu, Wei-Dong; Barbara A Foster; Trump, Donald L.; Johnson, Candace S.

    2009-01-01

    Calcitriol (1, 25-dihydroxycholecalciferol), the major active form of vitamin D, is anti-proliferative in tumor cells and tumor-derived endothelial cells (TDEC). These actions of calcitriol are mediated at least in part by vitamin D receptor (VDR), which is expressed in many tissues including endothelial cells. To investigate the role of VDR in calcitriol effects on tumor vasculature, we established TRAMP-2 tumors subcutaneously into either VDR wild type (WT) or knockout (KO) mice. Within 30 ...

  20. Differences between the neurogenic and proliferative abilities of Müller glia with stem cell characteristics and the ciliary epithelium from the adult human eye

    OpenAIRE

    Bhatia, Bhairavi; Jayaram, Hari; Singhal, Shweta; Jones, Megan F; Limb, G. Astrid

    2011-01-01

    Much controversy has arisen on the nature and sources of stem cells in the adult human retina. Whilst ciliary epithelium has been thought to constitute a source of neural stem cells, a population of Müller glia in the neural retina has also been shown to exhibit neurogenic characteristics. This study aimed to compare the neurogenic and proliferative abilities between these two major cell populations. It also examined whether differences exist between the pigmented and non-pigmented ciliary ep...

  1. Fate and metabolism of the brominated flame retardant tetrabromobisphenol A (TBBPA) in rice cell suspension culture.

    Science.gov (United States)

    Wang, Songfeng; Cao, Siqi; Wang, Yongfeng; Jiang, Bingqi; Wang, Lianhong; Sun, Feifei; Ji, Rong

    2016-07-01

    Tetrabromobisphenol A (TBBPA) is the brominated flame retardant with the highest production volume and its bioaccumulation in environment has caused both human health and environmental concerns, however the fate and metabolism of TBBPA in plants is unknown. We studied the fate, metabolites, and transformation of (14)C-labeled TBBPA in rice cell suspension culture. During the incubation for 14 days, TBBPA degradation occurred continuously in the culture, accompanied by formation of one anisolic metabolite [2,6-dibromo-4-(2-(2-hydroxy)-propyl)-anisole] (DBHPA) (50% of the degraded TBBPA) and cellular debris-bound residues (46.4%) as well as mineralization (3.6%). The cells continuously accumulated TBBPA in the cytoplasm, while a small amount of DBHPA (2.1% of the initially applied TBBPA) was detectable inside the cells only at the end of incubation. The majority of the accumulated residues in the cells was attributed to the cellular debris-bound residues, accounting for 70-79% of the accumulation after the first incubation day. About 5.4% of the accumulation was associated with cell organelles, which contributed 7.5% to the cellular debris-bound residues. Based on the fate and metabolism of TBBPA in the rice cell suspension culture, a type II ipso-substitution pathway was proposed to describe the initial step for TBBPA degradation in the culture and balance the fate of TBBPA in the cells. To the best of our knowledge, our study provides for the first time the insights into the fate and metabolism of TBBPA in plants and points out the potential role of type II ipso-hydroxylation substitution in degradation of alkylphenols in plants. Further studies are required to reveal the mechanisms for the bound-residue formation (e.g., binding of residues to specific cell wall components), nature of the binding, and toxicological effects of the bound residues and DBHPA. PMID:27105166

  2. Noble Hybrid Nanostructures as Efficient Anti-Proliferative Platforms for Human Breast Cancer Cell.

    Science.gov (United States)

    Tavangar, Amirhossein; Premnath, Priyatha; Tan, Bo; Venkatakrishnan, Krishnan

    2016-04-27

    Nanomaterials have proven to possess great potential in biomaterials research. Recently, they have suggested considerable promise in cancer diagnosis and therapy. Among others, silicon (Si) nanomaterials have been extensively employed for various biomedical applications; however, the utilization of Si for cancer therapy has been limited to nanoparticles, and its potential as anticancer substrates has not been fully explored. Noble nanoparticles have also received considerable attention owing to unique anticancer properties to improve the efficiency of biomaterials for numerous biological applications. Nevertheless, immobilization and control over delivery of the nanoparticles have been challenge. Here, we develop hybrid nanoplatforms to efficiently hamper breast cancer cell adhesion and proliferation. Platforms are synthesized by femtosecond laser processing of Si into multiphase nanostructures, followed by sputter-coating with gold (Au)/gold-palladium (Au-Pd) nanoparticles. The performance of the developed platforms was then examined by exploring the response of normal fibroblast and metastatic breast cancer cells. Our results from the quantitative and qualitative analyses show a dramatic decrease in the number of breast cancer cells on the hybrid platform compared to untreated substrates. Whereas, fibroblast cells form stable adhesion with stretched and elongated cytoskeleton and actin filaments. The hybrid platforms perform as dual-acting cytophobic/cytostatic stages where Si nanostructures depress breast cancer cell adhesion while immobilized Au/Au-Pd nanoparticles are gradually released to affect any surviving cell on the nanostructures. The nanoparticles are believed to be taken up by breast cancer cells via endocytosis, which subsequently alter the cell nucleus and may cause cell death. The findings suggest that the density of nanostructures and concentration of coated nanoparticles play critical roles on cytophobic/cytostatic properties of the platforms on

  3. Proliferative and apoptotic effects of andrographolide on the BGC-823 human gastric cancer cell line

    Institute of Scientific and Technical Information of China (English)

    LI Shu-guang; WANG Yuan-yu; YE Zai-yuan; SHAO Qing-shu; TAO Hou-quan; SHU Li-sha; ZHAO Yi-feng

    2013-01-01

    Background Andrographolide has been shown to have anticancer activity on diverse cancer cell lines representing different types of human cancers.The aim of this research was to investigate the anticancer and apoptotic effects of andrographolide on the BGC-823 human gastric cancer cell line.Methods Cell proliferation and IC50 were evaluated using MTT assay,cell-cycle analysis with flow cytometry apoptotic effects with Annexin-V/propidium iodide double-staining assay,and morphologic structure with transmission electron microscopy.Immunohistochemistry and reverse-transcription PCR was used to analyze Bcl-2,Bax,and caspase-3 expressions.Results Andrographolide showed a time-and concentration-dependent inhibitory effects on BGC-823 cell growth.Compared to controls,the number of cells in the G0-G1-phase increased significantly,S and G2-M-phase cells decreased after 48 hours of treatment with andrographolide,and both early and late apoptotic rates increased significantly compared to the controls,all in a concentration-dependent manner.Bax and caspase-3 expressions were markedly increased,and Bcl-2 expression was decreased.Conclusions Andrographolide inhibits BGC-823 cell growth and induces BGC-823 cell apoptosis by up-regulating Bax and caspase-3 expressions and down-regulating Bcl-2 expression.Andrographolide may be useful as a potent and selective agent in the treatment of human gastric cancers.

  4. Target antigen expression on a professional antigen-presenting cell induces superior proliferative antitumor T-cell responses via chimeric T-cell receptors.

    Science.gov (United States)

    Rossig, Claudia; Bär, Annette; Pscherer, Sibylle; Altvater, Bianca; Pule, Martin; Rooney, Cliona M; Brenner, Malcolm K; Jürgens, Heribert; Vormoor, Josef

    2006-01-01

    Human T cells expressing tumor antigen-specific chimeric receptors fail to sustain their growth and activation in vivo, which greatly reduces their therapeutic value. The defective proliferative response to tumor cells in vitro can partly be overcome by concomitant CD28 costimulatory signaling. We investigated whether T-cell activation via chimeric receptors (chRec) can be further improved by ligand expression on antigen-presenting cells of B-cell origin. We generated Epstein-Barr virus (EBV)-specific cytotoxic T lymphocytes (CTLs) expressing a CD19-specific chRec. These CTLs are provided with native receptor stimulation by autologous EBV-transformed B-lymphoblastoid cell lines (LCLs) but exclusively with chRec (CD19-specific) stimulation by allogeneic, human leukocyte antigen (HLA)-mismatched CD19+ LCLs. CD19zeta-transduced EBV-specific CTLs specifically lysed both allogeneic EBV targets and CD19+ tumor cells through the chRec in a major histocompatibility complex-independent manner, while maintaining their ability to recognize autologous EBV targets through the native T-cell receptor. The transduced CTLs failed to proliferate in response to CD19+ tumor targets even in the presence of CD28 costimulatory signaling. By contrast, CD19 expressed on HLA-mismatched LCL-induced T-cell activation and long-term proliferation that essentially duplicated the result from native receptor stimulation with autologous LCLs, suggesting that a deficit of costimulatory molecules on target cells in addition to CD28 is indeed responsible for inadequate chRec-mediated T-cell function. Hence, effective tumor immunotherapy may be favored if engagement of the chRec on modified T cells is complemented by interaction with multiple costimulator molecules. The use of T cells with native specificity for EBV may be one means of attaining this objective. PMID:16365597

  5. Role of Notch signaling in cell-fate determination of human mammary stem/progenitor cells

    International Nuclear Information System (INIS)

    Notch signaling has been implicated in the regulation of cell-fate decisions such as self-renewal of adult stem cells and differentiation of progenitor cells along a particular lineage. Moreover, depending on the cellular and developmental context, the Notch pathway acts as a regulator of cell survival and cell proliferation. Abnormal expression of Notch receptors has been found in different types of epithelial metaplastic lesions and neoplastic lesions, suggesting that Notch may act as a proto-oncogene. The vertebrate Notch1 and Notch4 homologs are involved in normal development of the mammary gland, and mutated forms of these genes are associated with development of mouse mammary tumors. In order to determine the role of Notch signaling in mammary cell-fate determination, we have utilized a newly described in vitro system in which mammary stem/progenitor cells can be cultured in suspension as nonadherent 'mammospheres'. Notch signaling was activated using exogenous ligands, or was inhibited using previously characterized Notch signaling antagonists. Utilizing this system, we demonstrate that Notch signaling can act on mammary stem cells to promote self-renewal and on early progenitor cells to promote their proliferation, as demonstrated by a 10-fold increase in secondary mammosphere formation upon addition of a Notch-activating DSL peptide. In addition to acting on stem cells, Notch signaling is also able to act on multipotent progenitor cells, facilitating myoepithelial lineage-specific commitment and proliferation. Stimulation of this pathway also promotes branching morphogenesis in three-dimensional Matrigel cultures. These effects are completely inhibited by a Notch4 blocking antibody or a gamma secretase inhibitor that blocks Notch processing. In contrast to the effects of Notch signaling on mammary stem/progenitor cells, modulation of this pathway has no discernable effect on fully committed, differentiated, mammary epithelial cells. These studies

  6. Engineering Cell Instructive Materials To Control Cell Fate and Functions through Material Cues and Surface Patterning.

    Science.gov (United States)

    Ventre, Maurizio; Netti, Paolo A

    2016-06-22

    Mastering the interaction between cells and extracellular environment is a fundamental prerequisite in order to engineer functional biomaterial interfaces able to instruct cells with specific commands. Such advanced biomaterials might find relevant application in prosthesis design, tissue engineering, diagnostics and stem cell biology. Because of the highly complex, dynamic, and multifaceted context, a thorough understanding of the cell-material crosstalk has not been achieved yet; however, a variety of material features including biological cues, topography, and mechanical properties have been proved to impact the strength and the nature of the cell-material interaction, eventually affecting cell fate and functions. Although the nature of these three signals may appear very different, they are equated by their participation in the same material-cytoskeleton crosstalk pathway as they regulate cell adhesion events. In this work we present recent and relevant findings on the material-induced cell responses, with a particular emphasis on how the presentation of biochemical/biophysical signals modulates cell behavior. Finally, we summarize and discuss the literature data to draw out unifying elements concerning cell recognition of and reaction to signals displayed by material surfaces. PMID:26693600

  7. Role of thrombin in the proliferative response of T-47D mammary tumor cells

    International Nuclear Information System (INIS)

    The growth of the human metastatic cell line (T-47D) in a chemically defined medium (DM) is shown to be dependent on the presence of three traditional growth factors: epidermal growth factor, insulin, and transferrin. The addition of thrombin further stimulates its growth. The mitogenic action on a human mammary tumor cell lines from epithelial origin is a novel action of thrombin. Cells in the DM show striking morphological changes which are dramatically enhanced by the addition of thrombin. These observations are part of a pleiotropic response to the growth factors: the protein content of the cells increases in the defined medium; the 2DG gels of the 35S- and 35P-labeled proteins show important changes in spots, several of which are probably of cytoskeletal origin. It is also shown that cells in a semisolid growth factor-supplemented medium have growth advantages over their counterparts grown with serum. All the phenotypic changes mentioned above reveal the important role of growth factors in the growth and behavior of this mammary cell line. The results obtained with thrombin indicate a new site of action of this enzyme which may be important in the metastatic spread of human mammary tumor cells

  8. Radiosensitivity of mouse seminal vesicle cells which show proliferative response to androgen and estrogen

    International Nuclear Information System (INIS)

    Injections of either androgen or estrogen have been shown to induce proliferation of epithelial cells in the seminal vesicle of castrated mice. Uptake of 5-[125I]iodo-2'-deoxyuridine ([125I]IdUrd) by the whole seminal vesicle was used as an index for cell proliferation. Although uptake of [125I]IdUrd induced by androgen was about four times as great as that induced by estrogen, both values decreased with a similar pattern after irradiation. Uptake of [125I]IdUrd showed a dose-dependent decrease up to 1000 rad; the values remained unchanged until 4000 rad. Uptake of [125I]IdUrd by the radiosensitive cell population was calculated by substracting [I-125]IdUrd uptake attributable to the radioresistant cell population from total [I-125]IdUrd uptake. Androgen- and estrogen-responsive cells were equally sensitive to irradiation. Recovery of androgen-responsive cells from radiation-induced decrease was examined with or without androgen stimulation. Although recovery occurred without androgen, it was significantly enhanced by androgen stimulation following irradiation. Irradiation seems useful for investigation of kinetic characteristics of epithelial stem cells in the seminal vesicle of mice

  9. Modulation of intracellular calcium and proliferative activity of invertebrate and vertebrate cells by ethylene

    Directory of Open Access Journals (Sweden)

    Müller Werner EG

    2001-05-01

    Full Text Available Abstract Background Ethylene is a widely distributed alkene product which is formed enzymatically (e.g., in plants or by photochemical reactions (e.g., in the upper oceanic layers from dissolved organic carbon. This gaseous compound was recently found to induce in cells from the marine sponge Suberites domuncula, an increase in intracellular Ca2+ level ([Ca2+]i and an upregulation of the expression of two genes, the potential ethylene-responsive gene, SDERR, and a Ca2+/calmodulin-dependent protein kinase. Results Here we describe for the first time, that besides sponge cells, mammalian cell lines (mouse NIH-3T3 and human HeLa and SaOS-2 cells respond to ethylene, generated by ethephon, with an immediate and strong, transient increase in [Ca2+]i level, as demonstrated using Fura-2 imaging method. A rise of [Ca2+]i level was also found following exposure to ethylene gas of cells kept under pressure (SaOS-2 cells. The upregulation of [Ca2+]i was associated with an increase in the level of the cell cycle-associated Ki-67 antigen. In addition, we show that the effect of ethephon addition to S. domuncula cells depends on the presence of calcium in the extracellular milieu. Conclusion The results presented in this paper indicate that ethylene, previously known to act as a mediator (hormone in plants only, deserves also attention as a potential signaling molecule in higher vertebrates. Further studies are necessary to clarify the specificity and physiological significance of the effects induced by ethylene in mammalian cells.

  10. Hydrogen peroxide – production, fate and role in redox signaling of tumor cells

    OpenAIRE

    Lennicke, Claudia; Rahn, Jette; Lichtenfels, Rudolf; Wessjohann, Ludger A; Seliger, Barbara

    2015-01-01

    Hydrogen peroxide (H2O2) is involved in various signal transduction pathways and cell fate decisions. The mechanism of the so called “redox signaling” includes the H2O2-mediated reversible oxidation of redox sensitive cysteine residues in enzymes and transcription factors thereby altering their activities. Depending on its intracellular concentration and localization, H2O2 exhibits either pro- or anti-apoptotic activities. In comparison to normal cells, cancer cells are characterized by an in...

  11. Fate mapping of interleukin-17 producing T cells in inflammatory responses

    OpenAIRE

    Stockinger, Brigitta B; Hirota, Keiji; Duarte, Joao H; Veldhoen, Marc; Hornsby, Eve; Li, Ying; Cua, Daniel J.; Tolaini, Mauro; Menzel, Ursula; Garefalaki, Anna; Potocnik, Alexandre J.; Wilhelm, Christoph; Ahlfors, Helena

    2011-01-01

    Abstract We describe a reporter mouse strain designed to fate-map cells that have activated IL-17A. Here we show that TH17 cells show distinct plasticity in different inflammatory settings. Chronic inflammatory conditions in EAE caused a switch to alternative cytokines in TH17 cells, whereas acute cutaneous infection with Candida albicans, did not result in deviation of TH17 to alternative cytokine production, although IL-17A production was shut off in the course of the infection ....

  12. GATA-3 Maintains the Differentiation of the Luminal Cell Fate in the Mammary Gland

    OpenAIRE

    Kouros-Mehr, Hosein; Slorach, Euan M.; Sternlicht, Mark D.; Werb, Zena

    2006-01-01

    The GATA family of transcription factors plays fundamental roles in cell-fate specification. However, it is unclear if these genes are necessary for the maintenance of cellular differentiation after development. We identified GATA-3 as the most highly enriched transcription factor in the mammary epithelium of pubertal mice. GATA-3 was found in the luminal cells of mammary ducts and the body cells of terminal end buds (TEBs). Upon conditional deletion of GATA-3, mice exhibited severe defects i...

  13. Induction of autophagy by proteasome inhibitor is associated with proliferative arrest in colon cancer cells

    International Nuclear Information System (INIS)

    The ubiquitin-proteasome system (UPS) and lysosome-dependent macroautophagy (autophagy) are two major intracellular pathways for protein degradation. Blockade of UPS by proteasome inhibitors has been shown to activate autophagy. Recent evidence also suggests that proteasome inhibitors may inhibit cancer growth. In this study, the effect of a proteasome inhibitor MG-132 on the proliferation and autophagy of cultured colon cancer cells (HT-29) was elucidated. Results showed that MG-132 inhibited HT-29 cell proliferation and induced G2/M cell cycle arrest which was associated with the formation of LC3+ autophagic vacuoles and the accumulation of acidic vesicular organelles. MG-132 also increased the protein expression of LC3-I and -II in a time-dependent manner. In this connection, 3-methyladenine, a Class III phosphoinositide 3-kinase inhibitor, significantly abolished the formation of LC3+ autophagic vacuoles and the expression of LC3-II but not LC3-I induced by MG-132. Taken together, this study demonstrates that inhibition of proteasome in colon cancer cells lowers cell proliferation and activates autophagy. This discovery may shed a new light on the novel function of proteasome in the regulation of autophagy and proliferation in colon cancer cells

  14. Investigation of cell proliferative activity on the surface of the nanocomposite material produced by laser radiation

    Science.gov (United States)

    Zhurbina, N. N.; Kurilova, U. E.; Ickitidze, L. P.; Podgaetsky, V. M.; Selishchev, S. V.; Suetina, I. A.; Mezentseva, M. V.; Eganova, E. M.; Pavlov, A. A.; Gerasimenko, A. Y.

    2016-04-01

    A new method for the formation of composite nanomaterials based on multi-walled and single-walled carbon nanotubes (CNT) on a silicon substrate has been developed. Formation is carried out by ultrasound coating of a silicon substrate by homogenous dispersion of CNTs in the albumin matrix and further irradiation with the continuous laser beam with a wavelength of 810 nm and power of 5.5 watts. The high electrical conductivity of CNTs provides its structuring under the influence of the laser radiation electric field. The result is a scaffold that provides high mechanical strength of nanocomposite material (250 MPa). For in vitro studies of materials biocompatibility a method of cell growth microscopic analysis was developed. Human embryonic fibroblasts (EPP) were used as biological cells. Investigation of the interaction between nanocomposite material and cells was carried out by optical and atomic force microscopy depending on the time of cells incubation. The study showed that after 3 hours incubation EPP were fixed on the substrate surface, avoiding the surface of the composite material. However, after 24 hours of incubation EPP fix on the sample surface and then begin to grow and divide. After 72 hours of incubation, the cells completely fill the sample surface of nanocomposite material. Thus, a nanocomposite material based on CNTs in albumin matrix does not inhibit cell growth on its surface, and favours their growth. The nanocomposite material can be used for creating soft tissue implants

  15. Anti-Proliferative Effects of Siegesbeckia orientalis Ethanol Extract on Human Endometrial RL-95 Cancer Cells

    Directory of Open Access Journals (Sweden)

    Chi-Chang Chang

    2014-12-01

    Full Text Available Endometrial cancer is a common malignancy of the female genital tract. This study demonstrates that Siegesbeckia orientalis ethanol extract (SOE significantly inhibited the proliferation of RL95-2 human endometrial cancer cells. Treating RL95-2 cells with SOE caused cell arrest in the G2/M phase and induced apoptosis of RL95-2 cells by up-regulating Bad, Bak and Bax protein expression and down-regulation of Bcl-2 and Bcl-xL protein expression. Treatment with SOE increased protein expression of caspase-3, -8 and -9 dose-dependently, indicating that apoptosis was through the intrinsic and extrinsic apoptotic pathways. Moreover, SOE was also effective against A549 (lung cancer, Hep G2 (hepatoma, FaDu (pharynx squamous cancer, MDA-MB-231 (breast cancer, and especially on LNCaP (prostate cancer cell lines. In total, 10 constituents of SOE were identified by Gas chromatography-mass analysis. Caryophyllene oxide and caryophyllene are largely responsible for most cytotoxic activity of SOE against RL95-2 cells. Overall, this study suggests that SOE is a promising anticancer agent for treating endometrial cancer.

  16. Anti-Proliferative Effect of Copper Oxide Nanorods Against Human Cervical Carcinoma Cells.

    Science.gov (United States)

    Pandurangan, Muthuraman; Nagajyothi, P C; Shim, Jaesool; Kim, Doo Hwan

    2016-09-01

    Metal oxide nanoparticles have been widely investigated for its use in the pharmacological field. The present study was aimed to investigate the cytotoxicity of copper oxide nanorods in human cervical carcinoma cells. The effect of copper oxide nanorods on cell viability was determined by sulforhodamine-B (SRB) assay. The fluorescence and confocal microscopy analyzes showed the cell rounding and nuclear fragmentation following exposure of copper oxide nanorods. Reactive oxygen species (ROS) was increased and could initiate membrane lipid peroxidation, which in turn regulate cytokinetic movements of cells. The messenger RNA (mRNA) expression of p53 and caspase 3 was increased, which further confirms the occurrence of apoptosis at the transcriptional level. Furthermore, caspase-3 enzyme activity was increased, which also confirms the occurrence of apoptosis in tumor cells at the translational level. Taking all our experimental results together, it may suggest that the copper oxide nanorods could be a potential anti-tumor agent to inhibit cancer cell proliferation. PMID:26811107

  17. Interrogating a cell signalling network sensitively monitors cell fate transition during early differentiation of mouse embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    LIU; Yi-Hsin; HO; Chih-ming

    2010-01-01

    The different cell types in an animal are often considered to be specified by combinations of transcription factors,and defined by marker gene expression.This paradigm is challenged,however,in stem cell research and application.Using a mouse embryonic stem cell(mESC) culture system,here we show that the expression level of many key stem cell marker genes/transcription factors such as Oct4,Sox2 and Nanog failed to monitor cell status transition during mESC differentiation.On the other hand,the response patterns of cell signalling network to external stimuli,as monitored by the dynamics of protein phosphorylation,changed dramatically.Our results also suggest that an irreversible alternation in the cell signalling network precedes the adjustment of transcription factor levels.This is consistent with the notion that signal transduction events regulate cell fate specification.We propose that interrogating a cell signalling network can assess the cell property more precisely,and provide a sensitive measurement for the early events in cell fate transition.We wish to bring attention to the potential problem of cell identification using a few marker genes,and suggest a novel methodology to address this issue.

  18. Human mammary progenitor cell fate decisions are products of interactions with combinatorial microenvironments

    Energy Technology Data Exchange (ETDEWEB)

    LaBarge, Mark A; Nelson, Celeste M; Villadsen, Rene; Fridriksdottir, Agla; Ruth, Jason R; Stampfer, Martha R; Petersen, Ole W; Bissell, Mina J

    2008-09-19

    In adult tissues, multi-potent progenitor cells are some of the most primitive members of the developmental hierarchies that maintain homeostasis. That progenitors and their more mature progeny share identical genomes, suggests that fate decisions are directed by interactions with extrinsic soluble factors, ECM, and other cells, as well as physical properties of the ECM. To understand regulation of fate decisions, therefore, would require a means of understanding carefully choreographed combinatorial interactions. Here we used microenvironment protein microarrays to functionally identify combinations of cell-extrinsic mammary gland proteins and ECM molecules that imposed specific cell fates on bipotent human mammary progenitor cells. Micropatterned cell culture surfaces were fabricated to distinguish between the instructive effects of cell-cell versus cell-ECM interactions, as well as constellations of signaling molecules; and these were used in conjunction with physiologically relevant 3 dimensional human breast cultures. Both immortalized and primary human breast progenitors were analyzed. We report on the functional ability of those proteins of the mammary gland that maintain quiescence, maintain the progenitor state, and guide progenitor differentiation towards myoepithelial and luminal lineages.

  19. Synergistic anti-proliferative effects of gambogic acid with docetaxel in gastrointestinal cancer cell lines

    Directory of Open Access Journals (Sweden)

    Zou Zhengyun

    2012-04-01

    Full Text Available Summary Background Gambogic acid has a marked anti-tumor effect for gastric and colorectal cancers in vitro and in vivo. However, recent investigations on gambogic acid have focused mainly on mono-drug therapy, and its potential role in cancer therapy has not been comprehensively illustrated. This study aimed to assess the interaction between gambogic acid and docetaxel on human gastrointestinal cancer cells and to investigate the mechanism of gambogic acid plus docetaxel treatment-induced apoptotic cell death. Methods MTT assay was used to determine IC50 values in BGC-823, MKN-28, LOVO and SW-116 cells after gambogic acid and docetaxel administration. Median effect analysis was applied for determination of synergism and antagonism. Synergistic interaction between gambogic acid and docetaxel was evaluated using the combination index (CI method. Furthermore, cellular apoptosis was analyzed by Annexin-V and propidium iodide (PI double staining. Additionally, mRNA expression of drug-associated genes, i.e., β-tublin III and tau, and the apoptosis-related gene survivin, were measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR. Results Gambogic acid provided a synergistic effect on the cytotoxicity induced by docetaxel in all four cell lines. The combined application of gambogic acid and docetaxel enhanced apoptosis in gastrointestinal cancer cells. Moreover, gambogic acid markedly decreased the mRNA expression of docetaxel-related genes, including β-tubulin III, tau and survivin, in BGC-823 cells. Conclusions Gambogic acid plus docetaxel produced a synergistic anti-tumor effect in gastrointestinal cancer cells, suggesting that the drug combination may offer a novel treatment option for patients with gastric and colorectal cancers.

  20. Proliferative effect of Hachimijiogan, a Japanese herbal medicine, in C2C12 skeletal muscle cells

    Directory of Open Access Journals (Sweden)

    Takeda T

    2015-02-01

    Full Text Available Takashi Takeda,1,2 Kenji Tsuiji,2 Bin Li,2 Mari Tadakawa,2 Nobuo Yaegashi2 1Division of Women’s Health, Research Institute of Traditional Asian Medicine, Kinki University School of Medicine, Osaka, Japan; 2Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Sendai, Japan Background: Hachimijiogan (HJG, Ba-Wei-Di-Huang-Wan in Chinese, is one of the most popular herbal medicines in Japanese Kampo. HJG is often prescribed for the prevention and treatment of age-related diseases. Muscle atrophy plays an important role in aging-related disabilities such as sarcopenia. The purpose of this study was to investigate the possible beneficial effect of HJG on skeletal muscle.Methods: Cells of murine skeletal muscle myoblast cell line C2C12 were used as an in vitro model of muscle cell proliferation and differentiation. The effect of HJG on C2C12 cell proliferation and differentiation was assessed. We counted the number of myotubes morphologically to assess the degree of differentiation.Results: HJG treatment (200 µg/mL for 3 days significantly increased C2C12 cell number by 1.23-fold compared with that of the control. HJG promoted the proliferation of C2C12 cells through activation of the ERK1/2 signaling pathway without affecting the Akt signaling pathway. HJG did not affect the differentiation of C2C12 cells. Conclusion: HJG had beneficial effects on skeletal muscle myoblast proliferation. These findings may provide a useful intervention for the prevention and treatment of sarcopenia. Keywords: ERK1/2 signaling pathway, herbal medicine, myoblast, proliferation, sarcopenia

  1. A deterministic map of Waddington's epigenetic landscape for cell fate specification

    Directory of Open Access Journals (Sweden)

    Andersen Melvin E

    2011-05-01

    Full Text Available Abstract Background The image of the "epigenetic landscape", with a series of branching valleys and ridges depicting stable cellular states and the barriers between those states, has been a popular visual metaphor for cell lineage specification - especially in light of the recent discovery that terminally differentiated adult cells can be reprogrammed into pluripotent stem cells or into alternative cell lineages. However the question of whether the epigenetic landscape can be mapped out quantitatively to provide a predictive model of cellular differentiation remains largely unanswered. Results Here we derive a simple deterministic path-integral quasi-potential, based on the kinetic parameters of a gene network regulating cell fate, and show that this quantity is minimized along a temporal trajectory in the state space of the gene network, thus providing a marker of directionality for cell differentiation processes. We then use the derived quasi-potential as a measure of "elevation" to quantitatively map the epigenetic landscape, on which trajectories flow "downhill" from any location. Stochastic simulations confirm that the elevation of this computed landscape correlates to the likelihood of occurrence of particular cell fates, with well-populated low-lying "valleys" representing stable cellular states and higher "ridges" acting as barriers to transitions between the stable states. Conclusions This quantitative map of the epigenetic landscape underlying cell fate choice provides mechanistic insights into the "forces" that direct cellular differentiation in the context of physiological development, as well as during artificially induced cell lineage reprogramming. Our generalized approach to mapping the landscape is applicable to non-gradient gene regulatory systems for which an analytical potential function cannot be derived, and also to high-dimensional gene networks. Rigorous quantification of the gene regulatory circuits that govern cell

  2. Roles of ERβ and GPR30 in Proliferative Response of Human Bladder Cancer Cell to Estrogen

    Directory of Open Access Journals (Sweden)

    Weiren Huang

    2015-01-01

    Full Text Available Bladder cancer belongs to one of the most common cancers and is a leading cause of deaths in our society. Urothelial carcinoma of the bladder (UCB is the main type of this cancer, and the estrogen receptors in UCB remain to be studied. Our experiment aimed to investigate the possible biological effect of 17β-estradiol on human bladder-derived T24 carcinoma cells and to indicate its related mechanisms. T24 cells were treated with various doses of 17β-estradiol, and cell proliferation was detected using MTT assays. 17β-estradiol promoted T24 cell proliferation independent of ERβ/GPR30-regulated EGFR-MAPK pathway, while it inhibited cell growth via GPR30. Furthermore, the expression levels of downstream genes (c-FOS, BCL-2, and CYCLIN D1 were increased by 17β-estradiol and this effect was independently associated with activity of the EGFR-MAPK pathway. The two estrogen receptors might be potential therapeutic targets for the treatment of bladder cancer.

  3. Gene expression in proliferative smooth muscle cells apoptosis of canine biliary duct induced by γ radiation

    International Nuclear Information System (INIS)

    By putting 103Pd-stent into canine biliary duct, proliferation of the smooth muscle cell, apoptosis and changes of the related genes after irradiation of canine biliary duct by 103Pd-stent are observed. The experimental dogs are randomly divided into a common-stent group and a 103Pd-stent group, 6 animals each group. Pathohistology, cell apoptosis, immuno -histochemistry for BCL-2 and FAS, RT-PCR for expression of Caspase-3 gene are performed. The results show: 1) The utmost intimal thickness of biliary duct in the 103Pd-stent group is obviously decreased comparing with the common-stent group after 30 days, and the percentages of the largest stenosis of the biliary duct are 54.73% and 17.61% (P103Pd-stent group are obviously decreased; 3) FAS and Caspase-3 expression in the 103Pd-stent group are consistent with cell apoptosis; 4) BCL-2 expression in the 10'3Pd-stent group is negatively related to FSA and Caspase-3 expressions. It indicats that γ radiation may induce caspase-3 gene activation which to lead the apoptosis of smooth muscle cells of canine biliary duct and to inhibit proliferation of smooth muscle cells and prevent restenosis of biliary duct. (authors)

  4. p53 is important for the anti-proliferative effect of ibuprofen in colon carcinoma cells

    International Nuclear Information System (INIS)

    S-ibuprofen which inhibits the cyclooxygenase-1/-2 and R-ibuprofen which shows no COX-inhibition at therapeutic concentrations have anti-carcinogenic effects in human colon cancer cells; however, the molecular mechanisms for these effects are still unknown. Using HCT-116 colon carcinoma cell lines, expressing either the wild-type form of p53 (HCT-116 p53wt) or being p(HCT-116 p53-/-), we demonstrated that both induction of a cell cycle block and apoptosis after S- and R-ibuprofen treatment is in part dependent on p53. Also in the in vivo nude mice model HCT-116 p53-/- xenografts were less sensitive for S- and R-ibuprofen treatment than HCT-116 p53wt cells. Furthermore, results indicate that induction of apoptosis in HCT-116 p53wt cells after ibuprofen treatment is in part dependent on a signalling pathway including the neutrophin receptor p75NTR, p53 and Bax

  5. Proliferative response of mouse spermatogonial stem cells after irradiation: a quantitative model analysis of experimental data

    International Nuclear Information System (INIS)

    The testes of CDF1 mice were irradiated with single doses of X-rays ranging from 2-16 Gy. The number of haploid cells in the testis at different times after irradiation (42-350 days) was determined by one-parameter flow cytometry both for irradiated animals and for age-matched controls. Based on literature data on the kinetics of the spermatogenesis in mice, a mathematical model of the (hierarchical) germ tissue was developed. Using this model, the processes of radiation-induced cell loss and subsequent recovery were simulated and free parameters of the model were estimated by fitting the model prediction to the experimental data. One of the aims of the study was to investigate the kinetic behaviour of spermatogonial stem cells and the corresponding control mechanisms. (author)

  6. Quantifying intrinsic and extrinsic control of single-cell fates in cancer and stem/progenitor cell pedigrees with competing risks analysis.

    Science.gov (United States)

    Cornwell, J A; Hallett, R M; der Mauer, S Auf; Motazedian, A; Schroeder, T; Draper, J S; Harvey, R P; Nordon, R E

    2016-01-01

    The molecular control of cell fate and behaviour is a central theme in biology. Inherent heterogeneity within cell populations requires that control of cell fate is studied at the single-cell level. Time-lapse imaging and single-cell tracking are powerful technologies for acquiring cell lifetime data, allowing quantification of how cell-intrinsic and extrinsic factors control single-cell fates over time. However, cell lifetime data contain complex features. Competing cell fates, censoring, and the possible inter-dependence of competing fates, currently present challenges to modelling cell lifetime data. Thus far such features are largely ignored, resulting in loss of data and introducing a source of bias. Here we show that competing risks and concordance statistics, previously applied to clinical data and the study of genetic influences on life events in twins, respectively, can be used to quantify intrinsic and extrinsic control of single-cell fates. Using these statistics we demonstrate that 1) breast cancer cell fate after chemotherapy is dependent on p53 genotype; 2) granulocyte macrophage progenitors and their differentiated progeny have concordant fates; and 3) cytokines promote self-renewal of cardiac mesenchymal stem cells by symmetric divisions. Therefore, competing risks and concordance statistics provide a robust and unbiased approach for evaluating hypotheses at the single-cell level. PMID:27250534

  7. Processing of whey modulates proliferative and immune functions in intestinal epithelial cells

    DEFF Research Database (Denmark)

    Nguyen, Duc Ninh; Sangild, Per Torp; Li, Yanqi;

    2016-01-01

    bioactive proteins and effects on proliferation and immune response in intestinal epithelial cells (IEC). The results showed that low-heat-treated WPC had elevated levels of lactoferrin and transforming growth factor-β2 compared with that of standard WPC. The level of aggregates depended on the source of...

  8. Proliferative responses and binding properties of hematopoietic cells transfected with low-affinity receptors for leukemia inhibitory factor, oncostatin M, and ciliary neurotrophic factor.

    OpenAIRE

    Gearing, D P; Ziegler, S F; Comeau, M R; Friend, D; Thoma, B; Cosman, D; Park, L.; Mosley, B

    1994-01-01

    Specific low-affinity receptors for leukemia inhibitory factor (LIF), oncostatin M (OSM; gp130), and ciliary neurotrophic factor (CNTF; receptor alpha, CNTFR alpha) may be utilized in various combinations to generate high-affinity binding sites and signal transduction. We have tested the ability of combinations of these receptors to transduce a proliferative signal in BAF-B03 cells. Coexpression of the LIF receptor and gp130 in these cells conferred high-affinity LIF and OSM binding and respo...

  9. Rare amplicons implicate frequent deregulation of cell fate specification pathways in oral squamous cell carcinoma.

    Science.gov (United States)

    Snijders, Antoine M; Schmidt, Brian L; Fridlyand, Jane; Dekker, Nusi; Pinkel, Daniel; Jordan, Richard C K; Albertson, Donna G

    2005-06-16

    Genomes of solid tumors are characterized by gains and losses of regions, which may contribute to tumorigenesis by altering gene expression. Often the aberrations are extensive, encompassing whole chromosome arms, which makes identification of candidate genes in these regions difficult. Here, we focused on narrow regions of gene amplification to facilitate identification of genetic pathways important in oral squamous cell carcinoma (SCC) development. We used array comparative genomic hybridization (array CGH) to define minimum common amplified regions and then used expression analysis to identify candidate driver genes in amplicons that spanned LAMA3, MMP7), as well as members of the hedgehog (GLI2) and notch (JAG1, RBPSUH, FJX1) pathways to be amplified and overexpressed. Deregulation of these and other members of the hedgehog and notch pathways (HHIP, SMO, DLL1, NOTCH4) implicates deregulation of developmental and differentiation pathways, cell fate misspecification, in oral SCC development. PMID:15824737

  10. Mitochondrial Dynamics Controls T Cell Fate through Metabolic Programming.

    Science.gov (United States)

    Buck, Michael D; O'Sullivan, David; Klein Geltink, Ramon I; Curtis, Jonathan D; Chang, Chih-Hao; Sanin, David E; Qiu, Jing; Kretz, Oliver; Braas, Daniel; van der Windt, Gerritje J W; Chen, Qiongyu; Huang, Stanley Ching-Cheng; O'Neill, Christina M; Edelson, Brian T; Pearce, Edward J; Sesaki, Hiromi; Huber, Tobias B; Rambold, Angelika S; Pearce, Erika L

    2016-06-30

    Activated effector T (TE) cells augment anabolic pathways of metabolism, such as aerobic glycolysis, while memory T (TM) cells engage catabolic pathways, like fatty acid oxidation (FAO). However, signals that drive these differences remain unclear. Mitochondria are metabolic organelles that actively transform their ultrastructure. Therefore, we questioned whether mitochondrial dynamics controls T cell metabolism. We show that TE cells have punctate mitochondria, while TM cells maintain fused networks. The fusion protein Opa1 is required for TM, but not TE cells after infection, and enforcing fusion in TE cells imposes TM cell characteristics and enhances antitumor function. Our data suggest that, by altering cristae morphology, fusion in TM cells configures electron transport chain (ETC) complex associations favoring oxidative phosphorylation (OXPHOS) and FAO, while fission in TE cells leads to cristae expansion, reducing ETC efficiency and promoting aerobic glycolysis. Thus, mitochondrial remodeling is a signaling mechanism that instructs T cell metabolic programming. PMID:27293185

  11. Anti-Proliferative Effect of an Aqueous Extract of Prunella vulgaris in Vascular Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Sun Mi Hwang

    2013-01-01

    Full Text Available The abnormal proliferation of vascular smooth muscle cells (VSMCs in arterial walls is an important pathogenic factor of vascular disorders such as diabetic atherosclerosis. We have reported the anti-inflammatory effect of an aqueous extract from Prunella vulgaris (APV in vascular endothelial cell. In the present study, APV exhibited inhibitory effects on high glucose-stimulated VSMC proliferation, migration, and invasion activities, inducing G1 cell cycle arrest with downregulation of cyclins and CDKs and upregulation of the CKIs, p21waf1/cip1 and p27kip1. Furthermore, APV dose dependently suppressed the high glucose-induced matrix metalloproteinase activity. High glucose-induced phosphorylation of ERK, p38 MAPK, was decreased by the pretreatment of APV. NF-κB activation by high glucose was attenuated by APV, as an antioxidant. APV attenuated the high glucose-induced decrease of nuclear factor E2-related factor-2 (Nrf2 translocation and heme oxygenase-1 (HO-1 expression. Intracellular cGMP level was also increased by APV treatment. These results demonstrate that APV may inhibit VSMC proliferation via downregulating ROS/NF-κB /ERK/p38 MAPK pathways. In addition, APV has a beneficial effect by the interaction of Nrf2-mediated NO/cGMP with HO-1, suggesting that Prunella vulgaris may be useful in preventing diabetic atherosclerosis.

  12. Anti-proliferative effect of leaf extracts of Eucalyptus citriodora against human cancer cells in vitro and in vivo.

    Science.gov (United States)

    Bhagat, Madhulika; Sharma, Vikas; Saxena, Ajit Kumar

    2012-12-01

    Six different extracts from Eucalyptus citriodora leaves were investigated for their anticancer effect. Extracts were prepared using a range of polar and non-polar solvents to leach out maximum active components. Phytochemical analysis of the extracts revealed the presence of anthraquinones, cardiac glycosides, flavonoids, saponins and tannins. Cytotoxic activity of different extracts was tested in vitro against seven human cancer cell lines from seven different tissues, such as SW-620 (colon), HOP-62 (lung), PC-3 (prostate), OVCAR-5 (ovary), HeLa (cervix), IMR-32 (neuroblastoma) and HEP-2 (liver). The ethyl acetate, chloroform and 50% methanolic extract displayed highest anti-proliferative effect in a dose-dependent manner. In vivo anti-tumor activity was evaluated against murine tumor (solid) model of Ehrlich ascites carcinoma and Sarcoma 180. The results showed that ethyl acetate and aqueous extracts suppressed the growth of Ehrlich ascites carcinoma (29.79% and 18.48%, respectively), but showed little growth inhibition in case of Sarcoma 180 (13. 86% and 8.57%, respectively). The activity might be due to the flavonoids, tannins and saponins that are present in all the extracts of the plant. Further investigation is required for the isolation of active principle(s) from the ethyl acetate extract, which has shown significant in vitro and in vivo anticancer potential. PMID:23350280

  13. Novel triterpenoid saponins from residual seed cake of Camellia oleifera Abel. show anti-proliferative activity against tumor cells.

    Science.gov (United States)

    Zong, Jianfa; Wang, Ruilong; Bao, Guanhu; Ling, Tiejun; Zhang, Liang; Zhang, Xinfu; Hou, Ruyan

    2015-07-01

    Four oleanane-type triterpenoid saponins were isolated from the seed cake of Camellia oleifera Abel.: camelliasaponin B1 and three new saponins, oleiferasaponin C1-C3 (1-3). Their structures were identified as 22-O-angeloyl-camelliagenin B 3-O-[β-d-galactopyranosyl-(1→2)]-[β-d-galactopyranosyl-(1→2)-α-l-arabinopyranosyl-(1→3)]-β-d-glucopyranosiduronic acid methyl ester (1); 22-O-angeloyl-camelliagenin A 3-O-[β-d-galactopyranosyl-(1→2)]-[β-d-glucopyranosyl-(1→2)-β-d-galactopyranosyl-(1→3)]-β-d-glucopyranosiduronic acid methyl ester (2); and 28-O-cinnamoyl-camelliagenin B 3-O-[β-d-galactopyranosylz-(1→2)] [β-d-galactopyranosyl(1→2)-α-l-arabinopyranosyl-(1→3)]-β-d-glucopyranosiduronic acid methyl ester (3) through 1D and 2D NMR, HR-ESI-MS, as well as GC-MS spectroscopic methods. The anti-proliferative activities of these four compounds were investigated on five human tumor cell lines (BEL-7402, BGC-823, MCF-7, HL-60 and KB). Compounds 1 and 2 and camelliasaponin B1 showed significant cytotoxic activities. PMID:25958771

  14. Stem cell fate determination during development and regeneration of ectodermal organs

    Directory of Open Access Journals (Sweden)

    LuciaJimenez-Rojo

    2012-04-01

    Full Text Available The development of ectoderm-derived appendages results in a large variety of highly specialized organs such as hair follicles, mammary glands, salivary glands and teeth. Despite varying in number, shape and function, all these ectodermal organs develop through continuous and reciprocal epithelial-mesenchymal interactions, sharing common morphological and molecular features especially during their embryonic development. Diseases such as ectodermal dysplasias can affect simultaneously these organs, suggesting that they may arise from common multipotent precursors residing in the embryonic ectoderm. During embryogenesis, these putative ectodermal stem cells may adopt different fates and consequently be able to generate a variety of tissue-specific stem cells, which are the sources for the various cell lineages that form the diverse organs. The specification of those common epithelial precursors, as well as their further lineage commitment to tissue-specific stem cells, might be controlled by specific signals. It has been well documented that Notch, Wnt, bone morphogenetic protein (BMP and fibroblast growth factor (FGF signaling pathways regulate cell fate decisions during the various stages of ectodermal organ development. However, the in vivo spatial and temporal dynamics of these signaling pathways are not yet well understood. Improving the current knowledge on the mechanisms involved in stem cell fate determination during organogenesis and homeostasis of ectodermal organs is crucial to develop effective stem cell-based therapies in order to regenerate or replace pathological and damaged tissues.

  15. JAK/STAT signaling regulates tissue outgrowth and male germline stem cell fate in Drosophila

    Institute of Scientific and Technical Information of China (English)

    Shree Ram SINGH; Xiu CHEN; Steven X.HOU

    2005-01-01

    In multicellular organisms, biological activities are regulated by cell signaling. The various signal transduction pathways regulate cell fate, proliferation, migration, and polarity. Miscoordination of the communicative signals will lead to disasters like cancer and other fatal diseases. The JAK/STAT signal transduction pathway is one of the pathways, which was first identified in vertebrates and is highly conserved throughout evolution. Studying the JAK/STAT signal transduction pathway in Drosophila provides an excellent opportunity to understand the molecular mechanism of the cell regulation during development and tumor formation. In this review, we discuss the general overview of JAK/STAT signaling in Drosophila with respect to its functions in the eye development and stem cell fate determination.

  16. Stem-cell dynamics and lineage topology from in vivo fate mapping in the hematopoietic system.

    Science.gov (United States)

    Höfer, Thomas; Barile, Melania; Flossdorf, Michael

    2016-06-01

    In recent years, sophisticated fate-mapping tools have been developed to study the behavior of stem cells in the intact organism. These experimental approaches are beginning to yield a quantitative picture of how cell numbers are regulated during steady state and in response to challenges. Focusing on hematopoiesis and immune responses, we discuss how novel mathematical approaches driven by these fate-mapping data have provided insights into the dynamics and topology of cellular differentiation pathways in vivo. The combination of experiment and theory has allowed to quantify the degree of self-renewal in stem and progenitor cells, shown how native hematopoiesis differs fundamentally from post-transplantation hematopoiesis, and uncovered that the diversification of T lymphocytes during immune responses resembles tissue renewal driven by stem cells. PMID:27107166

  17. Medium Renewal Blocks Anti-Proliferative Effects of Metformin in Cultured MDA-MB-231 Breast Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Maruša Rajh

    Full Text Available Epidemiological studies indicate that metformin, a widely used type 2 diabetes drug, might reduce breast cancer risk and mortality in patients with type 2 diabetes. Metformin might protect against breast cancer indirectly by ameliorating systemic glucose homeostasis. Alternatively, it might target breast cancer cells directly. However, experiments using MDA-MB-231 cells, a standard in vitro breast cancer model, produced inconsistent results regarding effectiveness of metformin as a direct anti-cancer agent. Metformin treatments in cultured MDA-MB-231 cells are usually performed for 48-96 hours, but protocols describing renewal of cell culture medium during these prolonged treatments are rarely reported. We determined whether medium renewal protocol might alter sensitivity of MDA-MB-231 cells treated with metformin. Using the MTS assay, BrdU incorporation and Hoechst staining we found that treatment with metformin for 48-72 hours failed to suppress viability and proliferation of MDA-MB-231 cells if low-glucose (1 g/L medium was renewed every 24 hours. Conversely, metformin suppressed their viability and proliferation if medium was not renewed. Without renewal glucose concentration in the medium was reduced to 0.1 g/L in 72 hours, which likely explains increased sensitivity to metformin under these conditions. We also examined whether 2-deoxy-D-glucose (2-DG reduces resistance to metformin. In the presence of 2-DG metformin reduced viability and proliferation of MDA-MB-231 cells with or without medium renewal, thus demonstrating that 2-DG reduces their resistance to metformin. In sum, we show that medium renewal blocks anti-proliferative effects of metformin during prolonged treatments in low-glucose medium. Differences in medium renewal protocols during prolonged treatments might therefore lead to apparently inconsistent results as regards effectiveness of metformin as a direct anti-cancer agent. Finally, our results indicate that co-therapy with

  18. Medium Renewal Blocks Anti-Proliferative Effects of Metformin in Cultured MDA-MB-231 Breast Cancer Cells.

    Science.gov (United States)

    Rajh, Maruša; Dolinar, Klemen; Miš, Katarina; Pavlin, Mojca; Pirkmajer, Sergej

    2016-01-01

    Epidemiological studies indicate that metformin, a widely used type 2 diabetes drug, might reduce breast cancer risk and mortality in patients with type 2 diabetes. Metformin might protect against breast cancer indirectly by ameliorating systemic glucose homeostasis. Alternatively, it might target breast cancer cells directly. However, experiments using MDA-MB-231 cells, a standard in vitro breast cancer model, produced inconsistent results regarding effectiveness of metformin as a direct anti-cancer agent. Metformin treatments in cultured MDA-MB-231 cells are usually performed for 48-96 hours, but protocols describing renewal of cell culture medium during these prolonged treatments are rarely reported. We determined whether medium renewal protocol might alter sensitivity of MDA-MB-231 cells treated with metformin. Using the MTS assay, BrdU incorporation and Hoechst staining we found that treatment with metformin for 48-72 hours failed to suppress viability and proliferation of MDA-MB-231 cells if low-glucose (1 g/L) medium was renewed every 24 hours. Conversely, metformin suppressed their viability and proliferation if medium was not renewed. Without renewal glucose concentration in the medium was reduced to 0.1 g/L in 72 hours, which likely explains increased sensitivity to metformin under these conditions. We also examined whether 2-deoxy-D-glucose (2-DG) reduces resistance to metformin. In the presence of 2-DG metformin reduced viability and proliferation of MDA-MB-231 cells with or without medium renewal, thus demonstrating that 2-DG reduces their resistance to metformin. In sum, we show that medium renewal blocks anti-proliferative effects of metformin during prolonged treatments in low-glucose medium. Differences in medium renewal protocols during prolonged treatments might therefore lead to apparently inconsistent results as regards effectiveness of metformin as a direct anti-cancer agent. Finally, our results indicate that co-therapy with 2-DG and

  19. Elevated Levels of Cytokines Associated with Th2 and Th17 Cells in Vitreous Fluid of Proliferative Diabetic Retinopathy Patients.

    Directory of Open Access Journals (Sweden)

    Masaru Takeuchi

    Full Text Available Macrophages are involved in low-grade inflammation in diabetes, and play pathogenic roles in proliferative diabetic retinopathy (PDR by producing proinflammatory cytokines. T cells as well as other cells are also activated by proinflammatory cytokines, and infiltration into the vitreous of patients with PDR has been shown. In this study, we measured helper T (Th cell-related cytokines in the vitreous of PDR patients to define the characteristics of Th-mediated immune responses associated with PDR. The study group consisted of 25 type 2 diabetic patients (25 eyes with PDR. The control group consisted of 27 patients with epiretinal membrane (ERM, 26 patients with idiopathic macular hole (MH, and 26 patients with uveitis associated with sarcoidosis. Vitreous fluid was obtained at the beginning of vitrectomy, and centrifuging for cellular removals was not performed. Serum was also collected from PDR patients. IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, soluble sCD40L, and TNFα in the vitreous and serum samples were measured. Both percent detectable and levels of IL-4, IL-6, IL-17A, IL-21, IL-22, and TNFα in the vitreous were significantly higher than those in the serum in PDR patients. Vitreous levels of these cytokines and IL-31 were significantly higher in PDR than in ERM or MH patients. Vitreous levels of IL-4, IL-17A, IL-22, IL-31, and TNFα in PDR patients were also significantly higher than those of sarcoidosis patients. In PDR patients, vitreous IL-17A level correlated significantly with vitreous levels of IL-22 and IL-31, and especially with IL-4 and TNFα. Although it is unclear whether these cytokines play facilitative roles or inhibitory roles for the progression of PDR, the present study indicated that Th2- and Th17-related immune responses are involved in the pathogenesis of PDR.

  20. Murine Lung Cancer Increases CD4+ T Cell Apoptosis and Decreases Gut Proliferative Capacity in Sepsis.

    Directory of Open Access Journals (Sweden)

    John D Lyons

    Full Text Available Mortality is significantly higher in septic patients with cancer than in septic patients without a history of cancer. We have previously described a model of pancreatic cancer followed by sepsis from Pseudomonas aeruginosa pneumonia in which cancer septic mice have higher mortality than previously healthy septic mice, associated with increased gut epithelial apoptosis and decreased T cell apoptosis. The purpose of this study was to determine whether this represents a common host response by creating a new model in which both the type of cancer and the model of sepsis are altered.C57Bl/6 mice received an injection of 250,000 cells of the lung cancer line LLC-1 into their right thigh and were followed three weeks for development of palpable tumors. Mice with cancer and mice without cancer were then subjected to cecal ligation and puncture and sacrificed 24 hours after the onset of sepsis or followed 7 days for survival.Cancer septic mice had a higher mortality than previously healthy septic mice (60% vs. 18%, p = 0.003. Cancer septic mice had decreased number and frequency of splenic CD4+ lymphocytes secondary to increased apoptosis without changes in splenic CD8+ numbers. Intestinal proliferation was also decreased in cancer septic mice. Cancer septic mice had a higher bacterial burden in the peritoneal cavity, but this was not associated with alterations in local cytokine, neutrophil or dendritic cell responses. Cancer septic mice had biochemical evidence of worsened renal function, but there was no histologic evidence of renal injury.Animals with cancer have a significantly higher mortality than previously healthy animals following sepsis. The potential mechanisms associated with this elevated mortality differ significantly based upon the model of cancer and sepsis utilized. While lymphocyte apoptosis and intestinal integrity are both altered by the combination of cancer and sepsis, the patterns of these alterations vary greatly depending on

  1. Xanthones from Garcinia paucinervis with in vitro anti-proliferative activity against HL-60 cells.

    Science.gov (United States)

    Li, Da-Hong; Li, Chen-Xi; Jia, Cui-Cui; Sun, Ya-Ting; Xue, Chun-Mei; Bai, Jiao; Hua, Hui-Ming; Liu, Xiao-Qiu; Li, Zhan-Lin

    2016-02-01

    Three new xanthones, paucinervins H-J (1-3), as well as eleven known compounds (4-14), were isolated from the leaves of Garcinia paucinervis. The structures of the new compounds (1-3) were elucidated by 1D, 2D NMR spectra and HR ESIMS. In vitro antiproliferative activity against human promyelocytic leukemia HL-60 cells was tested, among which, compounds 2, 5, 6 and 7 exhibited strong growth inhibitory effects with GI50 values ranging from 1.30 to 9.08 μM, respectively. Preliminary SARs were also discussed. PMID:26659874

  2. Allosteric Regulation of Histidine Kinases by Their Cognate Response Regulator Determines Cell Fate

    OpenAIRE

    Paul, Ralf; Jaeger, Tina; Abel, Sören; Wiederkehr, Irene; Folcher, Marc; Biondi, Emanuele G.; Laub, Michael T.; Jenal, Urs

    2008-01-01

    The two-component phosphorylation network is of critical importance for bacterial growth and physiology. Here, we address plasticity and interconnection of distinct signal transduction pathways within this network. In Caulobacter crescentus antagonistic activities of the PleC phosphatase and DivJ kinase localized at opposite cell poles control the phosphorylation state and subcellular localization of the cell fate determinator protein DivK. We show that DivK functions as an allosteric regulat...

  3. Oral squamous cell carcinoma proliferative phenotype is modulated by proanthocyanidins: a potential prevention and treatment alternative for oral cancer

    Directory of Open Access Journals (Sweden)

    Swapp Aaron

    2007-06-01

    Full Text Available Abstract Background Despite the recently reported drop in the overall death rate from cancer, the estimated survival rate and number of deaths from oral cancer remain virtually unchanged. Early detection efforts, in combination with strategies for prevention and risk-reduction, have the potential to dramatically improve clinical outcomes. The identification of non-toxic, effective treatments, including complementary and alternative therapies, is critical if the survival rate is to be improved. Epidemiologic studies have suggested a protective effect from certain plant-derived foods and extracts; however, it has been difficult to isolate and identify the compounds most responsible for these observations. The primary purpose of this study was to investigate the response of human oral squamous cell carcinoma (OSCC to proanthocyanidin (PAC, a plant-derived compound that may inhibit the progression of several other cancers. Methods Using a series of in vitro assays, we sought to quantify the effects of PAC on OSCC, cervical carcinoma, and non-cancerous cell lines, specifically the effects of PAC on cell proliferation. Recent data suggest that infection with the human papillomavirus (HPV may also modulate the proliferative potential of OSCC; therefore, we also measured the effects of PAC administration on HPV-transfected OSCC proliferation. Results Our results demonstrated that PAC administration was sufficient to significantly suppress cellular proliferation of OSCC in a dose-dependent manner. In addition, the increased proliferation of OSCC after transfection with HPV 16 was reduced by the administration of PAC, as was the proliferation of the cervical cancer and non-cancerous cell lines tested. Our results also provide preliminary evidence that PAC administration may induce apoptosis in cervical and oral cancer cell lines, while acting merely to suppress proliferation of the normal cell line control. Conclusion These results signify that PAC may be

  4. Structure of the Phosphatase Domain of the Cell Fate Determinant SpoIIE from Bacillus subtilis

    OpenAIRE

    Levdikov, Vladimir M; Blagova, Elena V.; Rawlings, Andrea E.; Jameson, Katie; Tunaley, James; Hart, Darren J.; Barak, Imrich; Wilkinson, Anthony J.

    2012-01-01

    Sporulation in Bacillus subtilis begins with an asymmetric cell division producing two genetically identical cells with different fates. SpoIIE is a membrane protein that localizes to the polar cell division sites where it causes FtsZ to relocate from mid-cell to form polar Z-rings. Following polar septation, SpoIIE establishes compartment-specific gene expression in the smaller forespore cell by dephosphorylating the anti-sigma factor antagonist SpoIIAA, leading to the release of the RNA pol...

  5. Highly proliferative primitive fetal liver hematopoietic stem cells are fueled by oxidative metabolic pathways

    Directory of Open Access Journals (Sweden)

    Javed K. Manesia

    2015-11-01

    Full Text Available Hematopoietic stem cells (HSCs in the fetal liver (FL unlike adult bone marrow (BM proliferate extensively, posing different metabolic demands. However, metabolic pathways responsible for the production of energy and cellular building blocks in FL HSCs have not been described. Here, we report that FL HSCs use oxygen dependent energy generating pathways significantly more than their BM counterparts. RNA-Seq analysis of E14.5 FL versus BM derived HSCs identified increased expression levels of genes involved in oxidative phosphorylation (OxPhos and the citric acid cycle (TCA. We demonstrated that FL HSCs contain more mitochondria than BM HSCs, which resulted in increased levels of oxygen consumption and reactive oxygen species (ROS production. Higher levels of DNA repair and antioxidant pathway gene expression may prevent ROS-mediated (genotoxicity in FL HSCs. Thus, we here for the first time highlight the underestimated importance of oxygen dependent pathways for generating energy and building blocks in FL HSCs.

  6. Developmental biology: cell fate in the mammary gland

    Science.gov (United States)

    Most breast cancers have their origin in the luminal epithelial cells of the mammary gland. Defining how a master regulator controls the development of this cell lineage could provide important hints about why this should be. ...

  7. Effects of prolonged moderate body deuteration on proliferative activity in major cell renewal systems in mice

    International Nuclear Information System (INIS)

    To evaluate the effects of prolonged moderate body deuteration on incorporation of tritiated thymidine (3HTdR) into the DNA of major cell renewal systems, young adult mice were given drinking fluid containing 30 % heavy water for 7, 14, 21, 42 and 70 days. Control mice drank tap water. Three hours prior to sacrifice, 925 kBq of HTdR were injected intravenously. Following extraction of the bulk of the soluble activity with an aqueous formalin solution, the residual 3H-activity of the organs was assayed by liquid scintillation counting and by autoradiography. The total thymic 3H-activity and the thymic weight, particularly of the cortex, were significantly reduced indeuterated mice early in the course of the experiment. The fraction of labeled thymocytes diminished to less than one half of the control values on day 70. The 3H-activity of the bone marrow in deuterated mice was reduced to about 3.4 of control values. In contrast, the total 3H-activity of the small intestine, as well as mean labeling index and mitotic index of small intestinal epithelia, were mot markedly altered in deuterated versus control mice. Drinking water containing 30 % of heavy water did thus not result in generalized, profound and progressive disturbance of HTdR incorporation in all the major cell renewal systems in the mouse. The thymus and, to a lesser extent, the bone marrow, were unquestionably affected, but the depression of HTdR incorporation did not increase markedly in the course of 10 weeks. In these terms, the toxicity of 30 % heavy wateer in the drinking fluid appears minor. This is of particular interest since exposure to similar concentrations is known to elicit immunodepressive and/or antineoplastic effects

  8. Changes in the proliferative activity of hippocampal neural stem cells from manganismus mice

    Institute of Scientific and Technical Information of China (English)

    Guohe Tan; Boning Yang; Guofu Tan; Bo Liang; Jiangu Gong; Xiaodong Ge; Songchao Guo

    2007-01-01

    BACKGROUND: Manganese neurotoxicity presents in the form of not only extracorticospinal tract injury of central nervous system (CNS), but also learning and memory ability damage. So, the mechanism of manganese neurotoxicity will be further studied from the angle ofhippocampus.OBJECTIVE: To observe the effects of manganism on learning and memory ability and the proliferation of neural stem cells (NSCs) in hippocampus of mouse brains, and analyze whether this effect has dose-dependence.DESIGN: Randomized controlled experiment.SETTING: Department of Human Anatomy, and Department of Industrial Hygiene and Occupational Diseases, Guangxi Medical University.MATERIALS: Twenty-eight male Kunming mice, aged 2 weeks, were involved in this experiment. The involved mice were randomized into 4 groups, with 7 in each: control group, low-dose manganism group,middle-dose manganism group and high-dose manganism group. Manganese chloride was purchased from Shantou Chemicals Factory.METHODS: This experiment was carried out in the Experimental Center for Preclinical Medicine, Guangxi Medical University from November 2005 to August 2006. Mice in the low-, middle- and high-dose manganism groups were intraperitoneally injected with 5, 20 and 50 mg/kg per day manganese chloride, once a day, for 2 weeks successively. Mice in the control group were injected with the same amount of stroke-physiological saline solution. Neurobehavioral detection of all the animals was performed in Morris water maze constantly from the 7th day after the first injection of manganese chloride solution. Learning ability was detected in the place navigation test. Mice were trained for 5 consecutive days with four trials per day. The time to find the platform was latency. Memory ability was detected in spatial probe test. Platform was withdrawn on the following day of place navigation. The mice were placed in the water from a random start in the edge of the pool. The number of times they traversed the plateform

  9. Cell adhesion geometry regulates non-random DNA segregation and asymmetric cell fates in mouse skeletal muscle stem cells.

    Science.gov (United States)

    Yennek, Siham; Burute, Mithila; Théry, Manuel; Tajbakhsh, Shahragim

    2014-05-22

    Cells of several metazoan species have been shown to non-randomly segregate their DNA such that older template DNA strands segregate to one daughter cell. The mechanisms that regulate this asymmetry remain undefined. Determinants of cell fate are polarized during mitosis and partitioned asymmetrically as the spindle pole orients during cell division. Chromatids align along the pole axis; therefore, it is unclear whether extrinsic cues that determine spindle pole position also promote non-random DNA segregation. To mimic the asymmetric divisions seen in the mouse skeletal stem cell niche, we used micropatterns coated with extracellular matrix in asymmetric and symmetric motifs. We show that the frequency of non-random DNA segregation and transcription factor asymmetry correlates with the shape of the motif and that these events can be uncoupled. Furthermore, regulation of DNA segregation by cell adhesion occurs within a defined time interval. Thus, cell adhesion cues have a major impact on determining both DNA segregation patterns and cell fates. PMID:24836002

  10. Cell Adhesion Geometry Regulates Non-Random DNA Segregation and Asymmetric Cell Fates in Mouse Skeletal Muscle Stem Cells

    Directory of Open Access Journals (Sweden)

    Siham Yennek

    2014-05-01

    Full Text Available Cells of several metazoan species have been shown to non-randomly segregate their DNA such that older template DNA strands segregate to one daughter cell. The mechanisms that regulate this asymmetry remain undefined. Determinants of cell fate are polarized during mitosis and partitioned asymmetrically as the spindle pole orients during cell division. Chromatids align along the pole axis; therefore, it is unclear whether extrinsic cues that determine spindle pole position also promote non-random DNA segregation. To mimic the asymmetric divisions seen in the mouse skeletal stem cell niche, we used micropatterns coated with extracellular matrix in asymmetric and symmetric motifs. We show that the frequency of non-random DNA segregation and transcription factor asymmetry correlates with the shape of the motif and that these events can be uncoupled. Furthermore, regulation of DNA segregation by cell adhesion occurs within a defined time interval. Thus, cell adhesion cues have a major impact on determining both DNA segregation patterns and cell fates.

  11. Processing of whey modulates proliferative and immune functions in intestinal epithelial cells.

    Science.gov (United States)

    Nguyen, Duc Ninh; Sangild, Per T; Li, Yanqi; Bering, Stine B; Chatterton, Dereck E W

    2016-02-01

    Whey protein concentrate (WPC) is often subjected to heat treatment during industrial processing, resulting in protein denaturation and loss of protein bioactivity. We hypothesized that WPC samples subjected to different degrees of thermal processing are associated with different levels of bioactive proteins and effects on proliferation and immune response in intestinal epithelial cells (IEC). The results showed that low-heat-treated WPC had elevated levels of lactoferrin and transforming growth factor-β2 compared with that of standard WPC. The level of aggregates depended on the source of whey, with the lowest level being found in WPC derived from acid whey. Following acid activation, WPC from acid whey enhanced IEC proliferation compared with WPC from sweet whey or nonactivated WPC. Low-heat-treated WPC from acid whey induced greater secretion of IL-8 in IEC than either standard WPC from acid whey or low-heat-treated WPC from sweet whey. Following acid activation (to activate growth factors), low-heat-treated WPC from sweet whey induced higher IL-8 levels in IEC compared with standard WPC from sweet whey. In conclusion, higher levels of bioactive proteins in low-heat-treated WPC, especially from acid whey, may enhance proliferation and cytokine responses of IEC. These considerations could be important to maintain optimal bioactivity of infant formulas, including their maturational and immunological effects on the developing intestine. PMID:26709184

  12. Phenotypic plasticity within yeast colonies: differential partitioning of cell fates.

    Science.gov (United States)

    Piccirillo, Sarah; Kapros, Tamas; Honigberg, Saul M

    2016-05-01

    Across many phyla, a common aspect of multicellularity is the organization of different cell types into spatial patterns. In the budding yeast Saccharomyces cerevisiae, after diploid colonies have completed growth, they differentiate to form alternating layers of sporulating cells and feeder cells. In the current study, we found that as yeast colonies developed, the feeder cell layer was initially separated from the sporulating cell layer. Furthermore, the spatial pattern of sporulation in colonies depended on the colony's nutrient environment; in two environments in which overall colony sporulation efficiency was very similar, the pattern of feeder and sporulating cells within the colony was very different. As noted previously, under moderately suboptimal conditions for sporulation-low acetate concentration or high temperature-the number of feeder cells increases as does the dependence of sporulation on the feeder-cell transcription factor, Rlm1. Here we report that even under a condition that is completely blocked sporulation, the number of feeder cells still increased. These results suggest broader implications to our recently proposed "Differential Partitioning provides Environmental Buffering" or DPEB hypothesis. PMID:26743103

  13. Experimental and theoretical study of possible correlation between the electrochemistry of canthin-6-one and the anti-proliferative activity against human cancer stem cells

    Science.gov (United States)

    Cebrián-Torrejón, G.; Doménech-Carbó, A.; Scotti, M. T.; Fournet, A.; Figadère, B.; Poupon, E.

    2015-12-01

    This work presents an approach to study the performance of novel targets able to overcome cancer stem cell chemoresistance, based on the voltammetric data for microparticulate films of natural or synthetic alkaloids from the canthin-6-one series. A comparison of this voltammetric technique with conventional solution phase electrochemistry suggests the differences in the anti-proliferative activity of canthin-6-ones could be tentatively correlated to their different capacity to generate semiquinone radical anions. These data also match theoretical calculations.

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

    OpenAIRE

    König, Heike

    2009-01-01

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

  15. Regulation of spindle orientation and neural stem cell fate in the Drosophila optic lobe

    Directory of Open Access Journals (Sweden)

    Brand Andrea H

    2007-01-01

    Full Text Available Abstract Background The choice of a stem cell to divide symmetrically or asymmetrically has profound consequences for development and disease. Unregulated symmetric division promotes tumor formation, whereas inappropriate asymmetric division affects organ morphogenesis. Despite its importance, little is known about how spindle positioning is regulated. In some tissues cell fate appears to dictate the type of cell division, whereas in other tissues it is thought that stochastic variation in spindle position dictates subsequent sibling cell fate. Results Here we investigate the relationship between neural progenitor identity and spindle positioning in the Drosophila optic lobe. We use molecular markers and live imaging to show that there are two populations of progenitors in the optic lobe: symmetrically dividing neuroepithelial cells and asymmetrically dividing neuroblasts. We use genetically marked single cell clones to show that neuroepithelial cells give rise to neuroblasts. To determine if a change in spindle orientation can trigger a neuroepithelial to neuroblast transition, we force neuroepithelial cells to divide along their apical/basal axis by misexpressing Inscuteable. We find that this does not induce neuroblasts, nor does it promote premature neuronal differentiation. Conclusion We show that symmetrically dividing neuroepithelial cells give rise to asymmetrically dividing neuroblasts in the optic lobe, and that regulation of spindle orientation and division symmetry is a consequence of cell type specification, rather than a mechanism for generating cell type diversity.

  16. Searching in mother nature for anti-cancer activity: anti-proliferative and pro-apoptotic effect elicited by green barley on leukemia/lymphoma cells.

    Directory of Open Access Journals (Sweden)

    Elisa Robles-Escajeda

    Full Text Available Green barley extract (GB was investigated for possible anti-cancer activity by examining its anti-proliferative and pro-apoptotic properties on human leukemia/lymphoma cell lines. Our results indicate that GB exhibits selective anti-proliferative activity on a panel of leukemia/lymphoma cells in comparison to non-cancerous cells. Specifically, GB disrupted the cell-cycle progression within BJAB cells, as manifested by G2/M phase arrest and DNA fragmentation, and induced apoptosis, as evidenced by phosphatidylserine (PS translocation to the outer cytoplasmic membrane in two B-lineage leukemia/lymphoma cell lines. The pro-apoptotic effect of GB was found to be independent of mitochondrial depolarization, thus implicating extrinsic cell death pathways to exert its cytotoxicity. Indeed, GB elicited an increase of TNF-α production, caspase-8 and caspase-3 activation, and PARP-1 cleavage within pre-B acute lymphoblastic leukemia Nalm-6 cells. Moreover, caspase-8 and caspase-3 activation and PARP-1 cleavage were strongly inhibited/blocked by the addition of the specific caspase inhibitors Z-VAD-FMK and Ac-DEVD-CHO. Furthermore, intracellular signaling analyses determined that GB treatment enhanced constitutive activation of Lck and Src tyrosine kinases in Nalm-6 cells. Taken together, these findings indicate that GB induced preferential anti-proliferative and pro-apoptotic signals within B-lineage leukemia/lymphoma cells, as determined by the following biochemical hallmarks of apoptosis: PS externalization, enhanced release of TNF-α, caspase-8 and caspase-3 activation, PARP-1 cleavage and DNA fragmentation Our observations reveal that GB has potential as an anti-leukemia/lymphoma agent alone or in combination with standard cancer therapies and thus warrants further evaluation in vivo to support these findings.

  17. Mark the transition: chromatin modifications and cell fate decision

    Institute of Scientific and Technical Information of China (English)

    Qiang Wu; Huck-Hui Ng

    2011-01-01

    With their unique features of selfrenewal and pluripotency,human embryonic stem (hES) cells are considered to be a nearly unlimited resource for research and clinical applications [1].Accordingly,the transcriptional network specifying and governing human ES cell identity has been extensively studied.OCT4,NANOG and SOX2 form a core transcriptional network that regulates itself as well as a number of target genes [2].This transcriptional network acts together with signaling pathways to maintain ES cell identity [3].Moreover,the last decade has seen tremendous advances in understanding the epigenetic mechanisms underlying ES eell self-renewal and pluripotency.

  18. Intestinal Neurogenin 3 Directs Differentiation of a Bipotential Secretory Progenitor to Endocrine Cell Rather than Goblet Cell Fate

    OpenAIRE

    López-Díaz, Lymari; Jain, Renu N.; Keeley, Theresa M.; VanDussen, Kelli L.; Brunkan, Cynthia S.; Gumucio, Deborah L.; Samuelson, Linda C.

    2007-01-01

    Neurogenin 3 is essential for enteroendocrine cell development; however, it is unknown whether this transcription factor is sufficient to induce an endocrine program in the intestine or how it affects the development of other epithelial cells originating from common progenitors. In this study, the mouse villin promoter was used to drive Neurogenin 3 expression throughout the developing epithelium to measure the affect on cell fate. Although the general morphology of the intestine was unchange...

  19. Fate of cerium dioxide nanoparticles in endothelial cells: exocytosis

    International Nuclear Information System (INIS)

    Although cytotoxicity and endocytosis of nanoparticles have been the subject of numerous studies, investigations regarding exocytosis as an important mechanism to reduce intracellular nanoparticle accumulation are rather rare and there is a distinct lack of knowledge. The current study investigated the behavior of human microvascular endothelial cells to exocytose cerium dioxide (CeO2) nanoparticles (18.8 nm) by utilization of specific inhibitors [brefeldin A; nocodazole; methyl-β-cyclodextrin (MβcD)] and different analytical methods (flow cytometry, transmission electron microscopy, inductively coupled plasma mass spectrometry). Overall, it was found that endothelial cells were able to release CeO2 nanoparticles via exocytosis after the migration of nanoparticle containing endosomes toward the plasma membrane. The exocytosis process occurred mainly by fusion of vesicular membranes with plasma membrane resulting in the discharge of vesicular content to extracellular environment. Nevertheless, it seems to be likely that nanoparticles present in the cytosol could leave the cells in a direct manner. MβcD treatment led to the strongest inhibition of the nanoparticle exocytosis indicating a significant role of the plasma membrane cholesterol content in the exocytosis process. Brefeldin A (inhibitor of Golgi-to-cell-surface-transport) caused a higher inhibitory effect on exocytosis than nocodazole (inhibitor of microtubules). Thus, the transfer from distal Golgi compartments to the cell surface influenced the exocytosis process of the CeO2 nanoparticles more than the microtubule-associated transport. In conclusion, endothelial cells, which came in contact with nanoparticles, e.g., after intravenously applied nano-based drugs, can regulate their intracellular nanoparticle amount, which is necessary to avoid adverse nanoparticle effects on cells

  20. Fate of cerium dioxide nanoparticles in endothelial cells: exocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Strobel, Claudia, E-mail: Claudia.Strobel@med.uni-jena.de [Jena University Hospital – Friedrich Schiller University Jena, Department of Experimental Radiology, Institute of Diagnostic and Interventional Radiology (Germany); Oehring, Hartmut [Jena University Hospital – Friedrich Schiller University Jena, Institute of Anatomy II (Germany); Herrmann, Rudolf [University of Augsburg, Department of Physics (Germany); Förster, Martin [Jena University Hospital – Friedrich Schiller University Jena, Department of Internal Medicine I, Division of Pulmonary Medicine and Allergy/Immunology (Germany); Reller, Armin [University of Augsburg, Department of Physics (Germany); Hilger, Ingrid, E-mail: ingrid.hilger@med.uni-jena.de [Jena University Hospital – Friedrich Schiller University Jena, Department of Experimental Radiology, Institute of Diagnostic and Interventional Radiology (Germany)

    2015-05-15

    Although cytotoxicity and endocytosis of nanoparticles have been the subject of numerous studies, investigations regarding exocytosis as an important mechanism to reduce intracellular nanoparticle accumulation are rather rare and there is a distinct lack of knowledge. The current study investigated the behavior of human microvascular endothelial cells to exocytose cerium dioxide (CeO{sub 2}) nanoparticles (18.8 nm) by utilization of specific inhibitors [brefeldin A; nocodazole; methyl-β-cyclodextrin (MβcD)] and different analytical methods (flow cytometry, transmission electron microscopy, inductively coupled plasma mass spectrometry). Overall, it was found that endothelial cells were able to release CeO{sub 2} nanoparticles via exocytosis after the migration of nanoparticle containing endosomes toward the plasma membrane. The exocytosis process occurred mainly by fusion of vesicular membranes with plasma membrane resulting in the discharge of vesicular content to extracellular environment. Nevertheless, it seems to be likely that nanoparticles present in the cytosol could leave the cells in a direct manner. MβcD treatment led to the strongest inhibition of the nanoparticle exocytosis indicating a significant role of the plasma membrane cholesterol content in the exocytosis process. Brefeldin A (inhibitor of Golgi-to-cell-surface-transport) caused a higher inhibitory effect on exocytosis than nocodazole (inhibitor of microtubules). Thus, the transfer from distal Golgi compartments to the cell surface influenced the exocytosis process of the CeO{sub 2} nanoparticles more than the microtubule-associated transport. In conclusion, endothelial cells, which came in contact with nanoparticles, e.g., after intravenously applied nano-based drugs, can regulate their intracellular nanoparticle amount, which is necessary to avoid adverse nanoparticle effects on cells.

  1. Tapetal cell fate, lineage and proliferation in the Arabidopsis anther.

    Science.gov (United States)

    Feng, Xiaoqi; Dickinson, Hugh G

    2010-07-01

    The four microsporangia of the flowering plant anther develop from archesporial cells in the L2 of the primordium. Within each microsporangium, developing microsporocytes are surrounded by concentric monolayers of tapetal, middle layer and endothecial cells. How this intricate array of tissues, each containing relatively few cells, is established in an organ possessing no formal meristems is poorly understood. We describe here the pivotal role of the LRR receptor kinase EXCESS MICROSPOROCYTES 1 (EMS1) in forming the monolayer of tapetal nurse cells in Arabidopsis. Unusually for plants, tapetal cells are specified very early in development, and are subsequently stimulated to proliferate by a receptor-like kinase (RLK) complex that includes EMS1. Mutations in members of this EMS1 signalling complex and its putative ligand result in male-sterile plants in which tapetal initials fail to proliferate. Surprisingly, these cells continue to develop, isolated at the locular periphery. Mutant and wild-type microsporangia expand at similar rates and the 'tapetal' space at the periphery of mutant locules becomes occupied by microsporocytes. However, induction of late expression of EMS1 in the few tapetal initials in ems1 plants results in their proliferation to generate a functional tapetum, and this proliferation suppresses microsporocyte number. Our experiments also show that integrity of the tapetal monolayer is crucial for the maintenance of the polarity of divisions within it. This unexpected autonomy of the tapetal 'lineage' is discussed in the context of tissue development in complex plant organs, where constancy in size, shape and cell number is crucial. PMID:20570940

  2. 1984: On monitoring cell fate in three-dimensional polymeric scaffolds for tissue engineering applications

    OpenAIRE

    Leferink, Anne Marijke

    2014-01-01

    In cartilage and bone engineering there is a high need for methods to replace traditional tissue and organ transplantation approaches to overcome the currently faced problems of donor shortage and invasiveness of the transplantation procedure. Although many promising advances have been made in the past decades in in vitro tissue engineering, quality control remains a challenge. Most conventional methods to assess the quality of a tissue engineered construct, e.g. by studying cell fate and tis...

  3. The acquisition of cell fate in the Arabidopsis thaliana root meristem

    OpenAIRE

    Scheres, B.J.G.; Berg, C. van den; Hage, W.; Willemsen, V; Werff, N. van der; Wolkenfelt, H.; McKhann, H.; Weisbeek, P.

    1997-01-01

    During plant embryogenesis an embryo with cotyledons, a shoot apical meristem, a hypocotyl and a root apical meristem, is formed. The primary root and shoot meristems initiate post-embryonic growth generating all plant organs. The root meristem forms the primary root, and the shoot meristem forms the aerial portion of the plant including secondary meristems. Histological and fate map data have shown that there is no precise correlation between the shoot meristem cells and their descendants. T...

  4. Prox1 physically and functionally interacts with COUP-TFII to specify lymphatic endothelial cell fate

    Science.gov (United States)

    Lee, Sunju; Kang, Jinjoo; Yoo, Jaehyuk; Ganesan, Sathish K.; Cook, Sarah C.; Aguilar, Berenice; Ramu, Swapnika; Lee, Juneyong

    2009-01-01

    Specification of endothelial cell (EC) fate during vascular development is controlled by distinct key regulators. While Notch plays an essential role in induction of arterial phenotypes, COUP-TFII is required to maintain the venous EC identity. Homeodomain transcription factor Prox1 functions to reprogram venous ECs to lymphatic endothelial cells (LECs). Here, we report that the venous EC fate regulator COUP-TFII is expressed in LECs throughout development and physically interacts with Prox1 to form a stable complex in various cell types including LECs. We found that COUP-TFII functions as a coregulator of Prox1 to control several lineage-specific genes including VEGFR-3, FGFR-3, and neuropilin-1 and is required along with Prox1 to maintain LEC phenotype. Together, we propose that the physical and functional interactions of the 2 proteins constitute an essential part in the program specifying LEC fate and may provide the molecular basis for the hypothesis of venous EC identity being the prerequisite for LEC specification. PMID:18815287

  5. Proliferative effects of gamma-amino butyric acid on oral squamous cell carcinoma cells are associated with mitogen-activated protein kinase signaling pathways.

    Science.gov (United States)

    Ma, Jing; Zhang, Yan; Wang, Jun; Zhao, Tianyu; Ji, Ping; Song, Jinlin; Zhang, Hongmei; Luo, Wenping

    2016-07-01

    Gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the adult mammalian central nervous system, has been reported to play an important physiological role in peripheral non-neuronal tissues, such as tumors. However, whether deregulated GABA is associated with oral squamous cell carcinoma (OSCC) is currently unknown. In this study, we investigated the effects of GABA on the proliferation of the OSCC cell line, Tca8113. Immunohistochemical analyses were performed to examine the expression of GABA A type receptor pi subunit (GABRP) in human OSCC tissues, and reverse transcription polymerase chain reaction, immunofluorescence staining and western blot analysis were performed to examine the expression of GABRP in Tca8113 cells. The proliferative effects of GABA on Tca8113 cells were analyzed by CCK-8 assay and flow cytometry. The activation status of mitogen-activated protein kinases (MAPKs) was examined by western blot analysis. GABRP expression was observed in the cytoplasm with a higher level in poorly differentiated OSCC tissues. The mRNA and protein expression levels of GABRP were detected in the Tca8113 cells. The addition of GABA and the GABA A type receptor agonist, Muscimol, promoted cell proliferation and inhibited cell apoptosis through the activation of the p38 MAPK and the inhibition of the JNK MAPK signaling pathways. These results imply a novel role of GABA in OSCC. PMID:27222045

  6. Transcriptional regulatory mechanisms that govern embryonic stem cell fate.

    Science.gov (United States)

    Das, Satyabrata; Levasseur, Dana

    2013-01-01

    Embryonic stem cells (ESCs) are defined by their simultaneous capacity for limitless self-renewal and the ability to specify cells borne of all germ layers. The regulation of ESC pluripotency is governed by a set of core transcription factors that regulate transcription by interfacing with nuclear proteins that include the RNA polymerase II core transcriptional machinery, histone modification enzymes, and chromatin remodeling protein complexes. The growing adoption of systems biological approaches used in stem cell biology over last few years has contributed significantly to our understanding of pluripotency. Multilayered approaches coupling transcriptome profiling and proteomics (Nanog-, Oct4-, and Sox2-centered protein interaction networks or "interactomes") with transcription factor chromatin occupancy and epigenetic footprint measurements have enabled a more comprehensive understanding of ESC pluripotency and self-renewal. Together with the genetic and biochemical characterization of promising pluripotency modifying proteins, these systems biological approaches will continue to clarify the molecular underpinnings of the ESC state. This will most certainly contribute to the improvement of current methodologies for the derivation of pluripotent cells from adult tissues. PMID:23756950

  7. Microspore embryogenesis: reprogramming cell fate from pollen to embryo development

    NARCIS (Netherlands)

    Hui Li,

    2014-01-01

    Microspore embryogenesis is an expression of plant cell totipotency that leads to the production of haploid embryos. Besides being a widely exploited plant breeding tool, microspore embryogenesis is also a fascinating system that can be used to obtain a deeper mechanistic understanding of plant toti

  8. Ubiquitin Ligases and Deubiquitinating Enzymes in CD4+ T Cell Effector Fate Choice and Function.

    Science.gov (United States)

    Layman, Awo A K; Oliver, Paula M

    2016-05-15

    The human body is exposed to potentially pathogenic microorganisms at barrier sites such as the skin, lungs, and gastrointestinal tract. To mount an effective response against these pathogens, the immune system must recruit the right cells with effector responses that are appropriate for the task at hand. Several types of CD4(+) T cells can be recruited, including Th cells (Th1, Th2, and Th17), T follicular helper cells, and regulatory T cells. These cells help to maintain normal immune homeostasis in the face of constantly changing microbes in the environment. Because these cells differentiate from a common progenitor, the composition of their intracellular milieu of proteins changes to appropriately guide their effector function. One underappreciated process that impacts the levels and functions of effector fate-determining factors is ubiquitylation. This review details our current understanding of how ubiquitylation regulates CD4(+) T cell effector identity and function. PMID:27183634

  9. Essential role of Bmp signaling and its positive feedback loop in the early cell fate evolution of chordates

    OpenAIRE

    Kozmiková, I. (Iryna); S Candiani; P. Fabian; Gurská, D. (Daniela); Kozmik, Z

    2013-01-01

    In chordates, early separation of cell fate domains occurs prior to the final specification of ectoderm to neural and non-neural as well as mesoderm to dorsal and ventral during development. Maintaining such division with the establishment of an exact border between the domains is required for the formation of highly differentiated structures such as neural tube and notochord. We hypothesized that the key condition for efficient cell fate separation in a chordate embryo is the presence of a p...

  10. The Adipocyte-Derived Hormone Leptin Has Proliferative Actions on Androgen-Resistant Prostate Cancer Cells Linking Obesity to Advanced Stages of Prostate Cancer

    Directory of Open Access Journals (Sweden)

    M. Raschid Hoda

    2012-01-01

    Full Text Available Background. Because obesity may be a risk factor for prostate cancer, we investigated proliferative effects of adipocytes-derived hormone leptin on human prostate cancer cells and assessed the role of mitogen-activated protein kinase (MAPK signaling pathway in mediating these actions. Material and Methods. Three human prostate cancer cell lines were treated with increasing doses of recombinant leptin. Cell growth was measured under serum-free conditions using a spectrophotometric assay. Further, Western blotting was applied to detect the phosphorylation of an ERK1/2, and a specific inhibitor of MAPK (PD98059; 40 μM was used. Results. In both androgen-resistant cell lines DU145 and PC-3, cell growth was dose-dependently increased by leptin after 24 hrs and 48 hrs of incubation, whereas leptin’s proliferative effects on androgen-sensitive cell line LNCaP was less pronounced. Further, leptin caused dose-dependent ERK1/2 phosphorylation in both androgen-resistant cell lines, and pretreatment of these cells with PD98059 inhibited these responses. Conclusions. Leptin may be a potential link between obesity and risk of progression of prostate cancer. Thus, studies on leptin and obesity association to prostate cancer should differentiate patients according to androgen sensitivity.

  11. Herpes simplex virus (HSV)-specific proliferative and cytotoxic T-cell responses in humans immunized with an HSF type 2 glycoprotein subunit vaccine

    International Nuclear Information System (INIS)

    Studies were undertaken to determine whether immunization of humans with a herpes simplex virus type 2 (HSV-2) glycoprotein-subunit vaccine would result in the priming of both HSV-specific proliferating cells and cytotoxic T cells. Peripheral blood lymphocytes (PBL) from all eight vaccinees studied responded by proliferating after stimulation with HSV-2, HSV-1, and glycoprotein gB-1. The PBL of five of these eight vaccinees proliferated following stimulation with gD-2, whereas stimulation with Gd-1 resulted in relatively low or no proliferative responses. T-cell clones were generated from HSV-2-stimulated PBL of three vaccinees who demonstrated strong proliferative responses to HSV-1 and HSV-2. Of 12 clones studied in lymphoproliferative assays, 9 were found to be cross-reactive for HSV-1 and HSV-2. Of the approximately 90 T-cell clones isolated, 14 demonstrated HSV-specific cytotoxic activity. Radioimmunoprecipitation-polyacrylamide gel electrophoresis analyses confirmed that the vaccinees had antibodies only to HSV glycoproteins, not to proteins which are absent in the subunit vaccine, indicating that these vaccinees had not become infected with HSV. Immunization of humans with an HSV-2 glycoprotein-subunit vaccine thus results in the priming of T cells that proliferate in response to stimulation with HSV and its glycoproteins and T cells that have cytotoxic activity against HSV-infected cells. Such HSV-specific memory T cells were detected as late as 2 years following the last boost with the subunit vaccine

  12. Fate of deposited cells in an aerobic binary bacterial biofilm

    International Nuclear Information System (INIS)

    A biofilm is a matrix of microbial cells and their extracellular products that is associated with a solid surface. Previous studies on biofilm development have employed only dissolved compounds as growth limiting substrates, without the influence of microbial species invading from the bulk liquid. The goal of this research project was to quantify the kinetics of processes governing suspended biomass turnover in biofilm systems, and the accompanying effects of suspended cell deposition on biofilm population dynamics. Experiments were conducted with two species of bacteria, Pseudomonas putida ATCC 11172 grown on glucose, and Hyphomicrobium ZV620 grown on methanol. Cryptic growth and particulate hydrolysis studies were evaluated, using combinations of these two bacteria, by measuring the uptake of radiolabelled cell lysis products, under batch conditions. Biofilms studies were performed to investigate bacterial deposition, continual biofilm removal by shear induced erosion, and biofilm ecology. Biofilms were developed in a flow cell reactor, under laminar flow conditions. Bacterial species were differentiated by radioactively labelling each species with their carbon substrate. A mathematical model was developed to predict the biofilm ecology of mixed cultures. The equations developed predict biofilm accumulation, as well as substrate and oxygen consumption. Results indicate that cryptic growth will occur for bacteria growing on their own species soluble lysis products and in some cases, bacteria growing on the soluble lysis products of other species. Particulate hydrolysis only occurred for Pseudomonas putida growing on Pseudomonas putida lysis products, but the lack of particulate hydrolysis occurring in the other studies may have been due to the short experimental period

  13. Environmental cues to guide stem cell fate decision for tissue engineering applications.

    Science.gov (United States)

    Alsberg, Eben; von Recum, Horst A; Mahoney, Melissa J

    2006-09-01

    The human body contains a variety of stem cells capable of both repeated self-renewal and production of specialised, differentiated progeny. Critical to the implementation of these cells in tissue engineering strategies is a thorough understanding of which external signals in the stem cell microenvironment provide cues to control their fate decision in terms of proliferation or differentiation into a desired, specific phenotype. These signals must then be incorporated into tissue regeneration approaches for regulated exposure to stem cells. The precise spatial and temporal presentation of factors directing stem cell behaviour is extremely important during embryogenesis, development and natural healing events, and it is possible that this level of control will be vital to the success of many regenerative therapies. This review covers existing tissue engineering approaches to guide the differentiation of three disparate stem cell populations: mesenchymal, neural and endothelial. These progenitor cells will be of central importance in many future connective, neural and vascular tissue regeneration technologies. PMID:16918253

  14. Viscoelastic Properties of Differentiating Blood Cells Are Fate- and Function-Dependent

    Science.gov (United States)

    Ekpenyong, Andrew E.; Whyte, Graeme; Chalut, Kevin; Pagliara, Stefano; Lautenschläger, Franziska; Fiddler, Christine; Paschke, Stephan; Keyser, Ulrich F.; Chilvers, Edwin R.; Guck, Jochen

    2012-01-01

    Although cellular mechanical properties are known to alter during stem cell differentiation, understanding of the functional relevance of such alterations is incomplete. Here, we show that during the course of differentiation of human myeloid precursor cells into three different lineages, the cells alter their viscoelastic properties, measured using an optical stretcher, to suit their ultimate fate and function. Myeloid cells circulating in blood have to be advected through constrictions in blood vessels, engendering the need for compliance at short time-scales (minutes), compared to undifferentiated cells. These findings suggest that reduction in steady-state viscosity is a physiological adaptation for enhanced migration through tissues. Our results indicate that the material properties of cells define their function, can be used as a cell differentiation marker and could serve as target for novel therapies. PMID:23028868

  15. Targeting pleiotropic signaling pathways to control adult cardiac stem cell fate and function

    Directory of Open Access Journals (Sweden)

    GiancarloForte

    2014-07-01

    Full Text Available The identification of different pools of cardiac progenitor cells resident in the adult mammalian heart opened a new era in heart regeneration as a means to restore the loss of functional cardiac tissue and overcome the limited availability of donor organs. Indeed, resident stem cells are believed to participate to tissue homeostasis and renewal in healthy and damaged myocardium although their actual contribution to these processes remain unclear. The poor outcome in terms of cardiac regeneration following tissue damage point out at the need for a deeper understanding of the molecular mechanisms controlling CPC behavior and fate determination before new therapeutic strategies can be developed. The regulation of cardiac resident stem cell fate and function is likely to result from the interplay between pleiotropic signaling pathways as well as tissue- and cell-specific regulators. Such a modular interaction – which has already been described in the nucleus of a number of different cells where transcriptional complexes form to activate specific gene programs - would account for the unique responses of cardiac progenitors to general and tissue-specific stimuli.The study of the molecular determinants involved in cardiac stem/progenitor cell regulatory mechanisms may shed light on the processes of cardiac homeostasis in health and disease and thus provide clues on the actual feasibility of cardiac cell therapy through tissue-specific progenitors.

  16. Laminopathies disrupt epigenomic developmental programs and cell fate.

    Science.gov (United States)

    Perovanovic, Jelena; Dell'Orso, Stefania; Gnochi, Viola F; Jaiswal, Jyoti K; Sartorelli, Vittorio; Vigouroux, Corinne; Mamchaoui, Kamel; Mouly, Vincent; Bonne, Gisèle; Hoffman, Eric P

    2016-04-20

    The nuclear envelope protein lamin A is encoded by thelamin A/C(LMNA) gene, which can contain missense mutations that cause Emery-Dreifuss muscular dystrophy (EDMD) (p.R453W). We fused mutated forms of the lamin A protein to bacterial DNA adenine methyltransferase (Dam) to define euchromatic-heterochromatin (epigenomic) transitions at the nuclear envelope during myogenesis (using DamID-seq). Lamin A missense mutations disrupted appropriate formation of lamin A-associated heterochromatin domains in an allele-specific manner-findings that were confirmed by chromatin immunoprecipitation-DNA sequencing (ChIP-seq) in murine H2K cells and DNA methylation studies in fibroblasts from muscular dystrophy patient who carried a distinctLMNAmutation (p.H222P). Observed perturbations of the epigenomic transitions included exit from pluripotency and cell cycle programs [euchromatin (open, transcribed) to heterochromatin (closed, silent)], as well as induction of myogenic loci (heterochromatin to euchromatin). In muscle biopsies from patients with either a gain- or change-of-functionLMNAgene mutation or a loss-of-function mutation in theemeringene, both of which cause EDMD, we observed inappropriate loss of heterochromatin formation at theSox2pluripotency locus, which was associated with persistent mRNA expression ofSox2 Overexpression ofSox2inhibited myogenic differentiation in human immortalized myoblasts. Our findings suggest that nuclear envelopathies are disorders of developmental epigenetic programming that result from altered formation of lamina-associated domains. PMID:27099177

  17. GATA3 induces human T-cell commitment by restraining Notch activity and repressing NK-cell fate.

    Science.gov (United States)

    Van de Walle, Inge; Dolens, Anne-Catherine; Durinck, Kaat; De Mulder, Katrien; Van Loocke, Wouter; Damle, Sagar; Waegemans, Els; De Medts, Jelle; Velghe, Imke; De Smedt, Magda; Vandekerckhove, Bart; Kerre, Tessa; Plum, Jean; Leclercq, Georges; Rothenberg, Ellen V; Van Vlierberghe, Pieter; Speleman, Frank; Taghon, Tom

    2016-01-01

    The gradual reprogramming of haematopoietic precursors into the T-cell fate is characterized by at least two sequential developmental stages. Following Notch1-dependent T-cell lineage specification during which the first T-cell lineage genes are expressed and myeloid and dendritic cell potential is lost, T-cell specific transcription factors subsequently induce T-cell commitment by repressing residual natural killer (NK)-cell potential. How these processes are regulated in human is poorly understood, especially since efficient T-cell lineage commitment requires a reduction in Notch signalling activity following T-cell specification. Here, we show that GATA3, in contrast to TCF1, controls human T-cell lineage commitment through direct regulation of three distinct processes: repression of NK-cell fate, upregulation of T-cell lineage genes to promote further differentiation and restraint of Notch activity. Repression of the Notch1 target gene DTX1 hereby is essential to prevent NK-cell differentiation. Thus, GATA3-mediated positive and negative feedback mechanisms control human T-cell lineage commitment. PMID:27048872

  18. Cyclin D2 in the basal process of neural progenitors is linked to non-equivalent cell fates

    OpenAIRE

    Tsunekawa, Yuji; Britto, Joanne M; Takahashi, Masanori; Polleux, Franck; Tan, Seong-Seng; Osumi, Noriko

    2012-01-01

    Localized translation of the cell-cycle regulator Cyclin D2 in the basal process of radial glial progenitor cells leads to its selective inheritance by the daughter cell undergoing self-renewal, thus representing a new mechanism for asymmetric cell fate determination.

  19. 1-calcium phosphate-uracil, a synthesized pyrimidine derivative agent, has anti-proliferative, pro-apoptotic and anti-invasion effects on multiple tumor cell lines

    OpenAIRE

    Peng, Jing; Chen, Xinlian; Hu, Qian; Yang, Mei; Liu, Hongqian; Wei, Wei; Liu, Shanling; Wang, HE

    2014-01-01

    1-calcium phosphate-uracil (1-CP-U), a synthetic pyrimidine derivative, has been documented to demonstrate a variety of different biological activities. However, the potency and mechanisms of this agent’s anti-cancer activity have not been elucidated to date. In the present study, the anti-cancer effects of 1-CP-U were examined in a range of in vitro assays. Different cell lines were treated with 1-CP-U at varied concentrations (0.7, 1.0, 1.4 μmol/l) for indicated durations. The cell prolifer...

  20. Pax6- and Six3-mediated induction of lens cell fate in mouse and human ES cells.

    Directory of Open Access Journals (Sweden)

    Raymond M Anchan

    Full Text Available Embryonic stem (ES cells provide a potentially useful in vitro model for the study of in vivo tissue differentiation. We used mouse and human ES cells to investigate whether the lens regulatory genes Pax6 and Six3 could induce lens cell fate in vitro. To help assess the onset of lens differentiation, we derived a new mES cell line (Pax6-GFP mES that expresses a GFP reporter under the control of the Pax6 P0 promoter and lens ectoderm enhancer. Pax6 or Six3 expression vectors were introduced into mES or hES cells by transfection or lentiviral infection and the differentiating ES cells analyzed for lens marker expression. Transfection of mES cells with Pax6 or Six3 but not with other genes induced the expression of lens cell markers and up-regulated GFP reporter expression in Pax6-GFP mES cells by 3 days post-transfection. By 7 days post-transfection, mES cell cultures exhibited a>10-fold increase over controls in the number of colonies expressing γA-crystallin, a lens fiber cell differentiation marker. RT-PCR and immunostaining revealed induction of additional lens epithelial or fiber cell differentiation markers including Foxe3, Prox1, α- and β-crystallins, and Tdrd7. Moreover, γA-crystallin- or Prox1-expressing lentoid bodies formed by 30 days in culture. In hES cells, Pax6 or Six3 lentiviral vectors also induced lens marker expression. mES cells that express lens markers reside close to but are distinct from the Pax6 or Six3 transduced cells, suggesting that the latter induce nearby undifferentiated ES cells to adopt a lens fate by non-cell autonomous mechanisms. In sum, we describe a novel mES cell GFP reporter line that is useful for monitoring induction of lens fate, and demonstrate that Pax6 or Six3 is sufficient to induce ES cells to adopt a lens fate, potentially via non-cell autonomous mechanisms. These findings should facilitate investigations of lens development.

  1. BRAF Mutation Is Associated With a Specific Cell Type With Features Suggestive of Senescence in Ovarian Serous Borderline (Atypical Proliferative) Tumors

    DEFF Research Database (Denmark)

    Zeppernick, Felix; Ardighieri, Laura; Hannibal, Charlotte G;

    2014-01-01

    Serous borderline tumor also known as atypical proliferative serous tumor (APST) is the precursor of ovarian low-grade serous carcinoma (LGSC). In this study, we correlated the morphologic and immunohistochemical phenotypes of 71 APSTs and 18 LGSCs with the mutational status of KRAS and BRAF, the...... LGSCs, EC cells were found in only 2, and both contained BRAF mutations. The EC cells were present admixed with cuboidal and columnar cells lining the papillae and appeared to be budding from the surface, resulting in individual cells and clusters of detached cells "floating" above the papillae...... of ovarian tumors by showing that BRAF mutation is associated with cellular senescence and the presence of a specific cell type characterized by abundant EC. This "oncogene-induced senescence" phenotype may represent a mechanism that impedes progression of APSTs to LGSC....

  2. Dynamic Pax6 expression during the neurogenic cell cycle influences proliferation and cell fate choices of retinal progenitors

    Directory of Open Access Journals (Sweden)

    Yang Xian-Jie

    2009-08-01

    Full Text Available Abstract Background The paired homeobox protein Pax6 is essential for proliferation and pluripotency of retinal progenitors. However, temporal changes in Pax6 protein expression associated with the generation of various retinal neurons have not been characterized with regard to the cell cycle. Here, we examine the dynamic changes of Pax6 expression among chicken retinal progenitors as they progress through the neurogenic cell cycle, and determine the effects of altered Pax6 levels on retinogenesis. Results We provide evidence that during the preneurogenic to neurogenic transition, Pax6 protein levels in proliferating progenitor cells are down-regulated. Neurogenic retinal progenitors retain a relatively low level of Pax6 protein, whereas postmitotic neurons either elevate or extinguish Pax6 expression in a cell type-specific manner. Cell imaging and cell cycle analyses show that neurogenic progenitors in the S phase of the cell cycle contain low levels of Pax6 protein, whereas a subset of progenitors exhibits divergent levels of Pax6 protein upon entering the G2 phase of the cell cycle. We also show that M phase cells contain varied levels of Pax6, and some correlate with the onset of early neuronal marker expression, forecasting cell cycle exit and cell fate commitment. Furthermore, either elevating or knocking down Pax6 attenuates cell proliferation and results in increased cell death. Reducing Pax6 decreases retinal ganglion cell genesis and enhances cone photoreceptor and amacrine interneuron production, whereas elevating Pax6 suppresses cone photoreceptor and amacrine cell fates. Conclusion These studies demonstrate for the first time quantitative changes in Pax6 protein expression during the preneurogenic to neurogenic transition and during the neurogenic cell cycle. The results indicate that Pax6 protein levels are stringently controlled in proliferating progenitors. Maintaining a relatively low Pax6 protein level is necessary for S phase

  3. Gastrin: a distinct fate of neurogenin3 positive progenitor cells in the embryonic pancreas.

    Directory of Open Access Journals (Sweden)

    Yaron Suissa

    Full Text Available Neurogenin3(+ (Ngn3(+ progenitor cells in the developing pancreas give rise to five endocrine cell types secreting insulin, glucagon, somatostatin, pancreatic polypeptide and ghrelin. Gastrin is a hormone produced primarily by G-cells in the stomach, where it functions to stimulate acid secretion by gastric parietal cells. Gastrin is expressed in the embryonic pancreas and is common in islet cell tumors, but the lineage and regulators of pancreatic gastrin(+ cells are not known. We report that gastrin is abundantly expressed in the embryonic pancreas and disappears soon after birth. Some gastrin(+ cells in the developing pancreas co-express glucagon, ghrelin or pancreatic polypeptide, but many gastrin(+ cells do not express any other islet hormone. Pancreatic gastrin(+ cells express the transcription factors Nkx6.1, Nkx2.2 and low levels of Pdx1, and derive from Ngn3(+ endocrine progenitor cells as shown by genetic lineage tracing. Using mice deficient for key transcription factors we show that gastrin expression depends on Ngn3, Nkx2.2, NeuroD1 and Arx, but not Pax4 or Pax6. Finally, gastrin expression is induced upon differentiation of human embryonic stem cells to pancreatic endocrine cells expressing insulin. Thus, gastrin(+ cells are a distinct endocrine cell type in the pancreas and an alternative fate of Ngn3+ cells.

  4. The G protein-coupled receptor GPR30 mediates the proliferative and invasive effects induced by hydroxytamoxifen in endometrial cancer cells

    International Nuclear Information System (INIS)

    Highlights: ► We assessed hydroxytamoxifen (OHT) effects in two endometrial cancer cell lines. ► GPR30 mediates the proliferative effects induced by OHT. ► GPR30 mediates the invasive effects induced by OHT. ► GPR30 expression was up-regulated by OHT in endometrial cancer cell line. -- Abstract: The selective ER modulator tamoxifen (TAM) is the most widely used ER antagonist for treatment of women with hormone-dependent breast tumor. However, long-term treatment is associated with an increased risk of endometrial cancer. The aim of the present study was to demonstrate new insight into the role of G-protein coupled receptor 30 (GPR30) in the activity of TAM, which promoted endometrial cancer. In endometrial cancer cell lines ISHIKAWA and KLE, the potential of 4-hydroxytamoxifen (OHT), the active metabolite of TAM, 17β-estradiol (E2) and G1, a non-steroidal GPR30-specific agonist to promote cell proliferation and invasion was evaluated. All agents above induced high proliferative and invasive effects, while the down-regulation of GPR30 or the interruption of MAPK signal pathway partly or completely prevented the action of the regent. Moreover, the RNA and protein expression of GPR30 was up-regulated by G1, E2 or OHT in both cell lines. The present study provided a new insight into the mechanism involved in the agonistic activity exerted by TAM in the uterus.

  5. The G protein-coupled receptor GPR30 mediates the proliferative and invasive effects induced by hydroxytamoxifen in endometrial cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Du, Gui-Qiang; Zhou, Long; Chen, Xiao-Yue [Department of Obstetrics and Gynecology, The International Peace Maternity and Child Health Hospital of the China Welfare Institute Affiliated to Shanghai Jiao Tong University, 910, Hengshan Road, Shanghai (China); Wan, Xiao-Ping, E-mail: wanxiaoping61@126.com [Department of Obstetrics and Gynecology, The International Peace Maternity and Child Health Hospital of the China Welfare Institute Affiliated to Shanghai Jiao Tong University, 910, Hengshan Road, Shanghai (China); He, Yin-Yan [Department of Obstetrics and Gynecology, Shanghai First People' s Hospital, Shanghai Jiao Tong University, Shanghai (China)

    2012-04-06

    Highlights: Black-Right-Pointing-Pointer We assessed hydroxytamoxifen (OHT) effects in two endometrial cancer cell lines. Black-Right-Pointing-Pointer GPR30 mediates the proliferative effects induced by OHT. Black-Right-Pointing-Pointer GPR30 mediates the invasive effects induced by OHT. Black-Right-Pointing-Pointer GPR30 expression was up-regulated by OHT in endometrial cancer cell line. -- Abstract: The selective ER modulator tamoxifen (TAM) is the most widely used ER antagonist for treatment of women with hormone-dependent breast tumor. However, long-term treatment is associated with an increased risk of endometrial cancer. The aim of the present study was to demonstrate new insight into the role of G-protein coupled receptor 30 (GPR30) in the activity of TAM, which promoted endometrial cancer. In endometrial cancer cell lines ISHIKAWA and KLE, the potential of 4-hydroxytamoxifen (OHT), the active metabolite of TAM, 17{beta}-estradiol (E2) and G1, a non-steroidal GPR30-specific agonist to promote cell proliferation and invasion was evaluated. All agents above induced high proliferative and invasive effects, while the down-regulation of GPR30 or the interruption of MAPK signal pathway partly or completely prevented the action of the regent. Moreover, the RNA and protein expression of GPR30 was up-regulated by G1, E2 or OHT in both cell lines. The present study provided a new insight into the mechanism involved in the agonistic activity exerted by TAM in the uterus.

  6. Removal of damaged proteins during ES cell fate specification requires the proteasome activator PA28

    DEFF Research Database (Denmark)

    Hernebring, Malin; Fredriksson, Asa; Liljevald, Maria; Cvijovic, Marija; Norrman, Karin; Wiseman, John; Semb, Tor Henrik; Nyström, Thomas

    2013-01-01

    In embryonic stem cells, removal of oxidatively damaged proteins is triggered upon the first signs of cell fate specification but the underlying mechanism is not known. Here, we report that this phase of differentiation encompasses an unexpected induction of genes encoding the proteasome activato...... that PA28aß has a hitherto unidentified role required for resetting the levels of protein damage at the transition from self-renewal to cell differentiation.......In embryonic stem cells, removal of oxidatively damaged proteins is triggered upon the first signs of cell fate specification but the underlying mechanism is not known. Here, we report that this phase of differentiation encompasses an unexpected induction of genes encoding the proteasome activator...... PA28aß (11S), subunits of the immunoproteasome (20Si), and the 20Si regulator TNFa. This induction is accompanied by assembly of mature PA28-20S(i) proteasomes and elevated proteasome activity. Inhibiting accumulation of PA28a using miRNA counteracted the removal of damaged proteins demonstrating...

  7. SOX17 is a critical specifier of human primordial germ cell fate.

    Science.gov (United States)

    Irie, Naoko; Weinberger, Leehee; Tang, Walfred W C; Kobayashi, Toshihiro; Viukov, Sergey; Manor, Yair S; Dietmann, Sabine; Hanna, Jacob H; Surani, M Azim

    2015-01-15

    Specification of primordial germ cells (PGCs) marks the beginning of the totipotent state. However, without a tractable experimental model, the mechanism of human PGC (hPGC) specification remains unclear. Here, we demonstrate specification of hPGC-like cells (hPGCLCs) from germline competent pluripotent stem cells. The characteristics of hPGCLCs are consistent with the embryonic hPGCs and a germline seminoma that share a CD38 cell-surface marker, which collectively defines likely progression of the early human germline. Remarkably, SOX17 is the key regulator of hPGC-like fate, whereas BLIMP1 represses endodermal and other somatic genes during specification of hPGCLCs. Notable mechanistic differences between mouse and human PGC specification could be attributed to their divergent embryonic development and pluripotent states, which might affect other early cell-fate decisions. We have established a foundation for future studies on resetting of the epigenome in hPGCLCs and hPGCs for totipotency and the transmission of genetic and epigenetic information. PMID:25543152

  8. Neural stem cell sex dimorphism in aromatase (CYP19 expression: a basis for differential neural fate

    Directory of Open Access Journals (Sweden)

    Jay Waldron

    2010-11-01

    Full Text Available Jay Waldron1, Althea McCourty1, Laurent Lecanu1,21The Research Institute of the McGill University Health Centre, Montreal, Canada; 2Department of Medicine, McGill University, Quebec, CanadaPurpose: Neural stem cell (NSC transplantation and pharmacologic activation of endogenous neurogenesis are two approaches that trigger a great deal of interest as brain repair strategies. However, the success rate of clinical attempts using stem cells to restore neurologic functions altered either after traumatic brain injury or as a consequence of neurodegenerative disease remains rather disappointing. This suggests that factors affecting the fate of grafted NSCs are largely understudied and remain to be characterized. We recently reported that aging differentially affects the neurogenic properties of male and female NSCs. Although the sex steroids androgens and estrogens participate in the regulation of neurogenesis, to our knowledge, research on how gender-based differences affect the capacity of NSCs to differentiate and condition their neural fate is lacking. In the present study, we explored further the role of cell sex as a determining factor of the neural fate followed by differentiating NSCs and its relationship with a potential differential expression of aromatase (CYP19, the testosterone-metabolizing enzyme.Results: Using NSCs isolated from the subventricular zone of three-month-old male and female Long-Evans rats and maintained as neurospheres, we showed that differentiation triggered by retinoic acid resulted in a neural phenotype that depends on cell sex. Differentiated male NSCs mainly expressed markers of neuronal fate, including ßIII-tubulin, microtubule associated protein 2, growth-associated protein 43, and doublecortin. In contrast, female NSCs essentially expressed the astrocyte marker glial fibrillary acidic protein. Quantification of the expression of aromatase showed a very low level of expression in undifferentiated female NSCs

  9. Duel of the fates: the role of transcriptional circuits and noise in CD4+ cells.

    Science.gov (United States)

    Hebenstreit, Daniel; Deonarine, Andrew; Babu, M Madan; Teichmann, Sarah A

    2012-06-01

    CD4+ T cells play key roles in orchestrating adaptive immune responses, and are a popular model for mammalian cell differentiation. While immune regulation would seem to require exactly adjusted mRNA and protein expression levels of key factors, there is little evidence that this is strictly the case. Stochastic gene expression and plasticity of cell types contrast the apparent need for precision. Recent work has provided insight into the magnitude of molecular noise, as well as the relationship between noise, transcriptional circuits and epigenetic modifications in a variety of cell types. These processes and their interplay will also govern gene expression patterns in the different CD4+ cell types, and the determination of their cellular fates. PMID:22498241

  10. The developmental fate of green fluorescent mouse embryonic germ cells in chimeric embryos

    Institute of Scientific and Technical Information of China (English)

    XUXIN; SUMIOSUGANO; 等

    1999-01-01

    Primordial germ cells (PGCs),as precursors of mammalian germ lineage,have been gaining more attention as a new resource of pluripotent stem cells,which bring a great possibility to study developmental events of germ cell in vitro and at animal level.EG4 cells derived from 10.5 days post coitum (dpc) PGCs of 129/svJ strain mouse were established and maintained in an undifferentiated state.With an attempt to study the differentiation capability of EG4 cells with a reporter protein:green fluorescence protein,and the possible application of EG4 cells in the research of germ cell development,we have generated several EG4-GFP cell lines expressing enhanced green fluorescence protein (EGFP) and still maintaining typical characteristics of pluripotent stem cells.Then,the differentiation of EG4-GFP cells in vitro as well as their developmental fate in chimeric embryos which were produced by aggregating EG4-GFP cells to 8-cell stage embryos were studied.The results showed that EG4 cells carrying green fluorescence have a potential use in the research of germ cell development and other related studies.

  11. The construction and proliferative effects of a lentiviral vector capable of stably overexpressing SPINK1 gene in human pancreatic cancer AsPC-1 cell line.

    Science.gov (United States)

    Zhang, Jing; Wang, Dongmei; Hu, Na; Wang, Qian; Yu, Shanice; Wang, Jun

    2016-05-01

    This study aims to design and generate recombinant lentiviral vector containing the complete coding sequence (CDS) region of human serine protease inhibitor Kazal type 1 gene (SPINK1) and establish a human pancreatic cancer cell line (AsPC-1) stably overexpressing SPINK1. Then, to assess the proliferative and oncogenic effects of upregulated SPINK1 gene on pancreatic cancer AsPC-1 cells using different methods. Initially, the target coding sequence (CDS) of SPINK1 was amplified by polymerase chain reaction (PCR) and the synthesized product was subsequently subcloned into the lentiviral vector. The construction of recombinant SPINK1 gene was verified by the restriction digestion and sequencing analysis. The lentiviral particles carrying SPINK1 gene were produced by co-transfection of the recombination lentiviral vector and the packaging mix plasmids into 293 T cells and filtered and concentrated before AsPC-1 cells were infected by the virus particles. The cells transduced were differentially selected with puromycin, and the clones that highly expressed SPINK1 were chosen by real-time PCR and confirmed by Western blot after 7 weeks. The stably transduced AsPC-1 cell line showed significantly increased metabolic and proliferative capability using CCK-8 and Trypan Blue assays (P < 0.001). Cell cycle and DNA content analysis by flow cytometry showed that upregulated SPINK1 elicited significant increase in the percentage of AsPC-1 cells in the S and G2/M phase (P < 0.001). Clone formation assay demonstrated that the number of the colonies formed in the experimental group was greater than that in the control parental cells (P < 0.001). It was concluded that a stable AsPC-1 cell line capable of overexpressing SPINK1 had been successfully created, and that the proliferative capacity of AsPC-1 pancreatic cancer cells was significantly raised by SPINK1 upregulation as well as the ability of a single AsPC-1 cell to grow into a colony. PMID:26586397

  12. Stem cell and progenitor fate in the mammalian intestine: Notch and lateral inhibition in homeostasis and disease

    Science.gov (United States)

    Sancho, Rocio; Cremona, Catherine A; Behrens, Axel

    2015-01-01

    The control of cell fate decisions is vital to build functional organs and maintain normal tissue homeostasis, and many pathways and processes cooperate to direct cells to an appropriate final identity. Because of its continuously renewing state and its carefully organised hierarchy, the mammalian intestine has become a powerful model to dissect these pathways in health and disease. One of the signalling pathways that is key to maintaining the balance between proliferation and differentiation in the intestinal epithelium is the Notch pathway, most famous for specifying distinct cell fates in adjacent cells via the evolutionarily conserved process of lateral inhibition. Here, we will review recent discoveries that advance our understanding of how cell fate in the mammalian intestine is decided by Notch and lateral inhibition, focusing on the molecular determinants that regulate protein turnover, transcriptional control and epigenetic regulation. PMID:25855643

  13. Putting things in place for fertilization: discovering roles for importin proteins in cell fate and spermatogenesis

    Directory of Open Access Journals (Sweden)

    Kate L. Loveland

    2015-01-01

    Full Text Available Importin proteins were originally characterized for their central role in protein transport through the nuclear pores, the only intracellular entry to the nucleus. This vital function must be tightly regulated to control access by transcription factors and other nuclear proteins to genomic DNA, to achieve appropriate modulation of cellular behaviors affecting cell fate. Importin-mediated nucleocytoplasmic transport relies on their specific recognition of cargoes, with each importin binding to distinct and overlapping protein subsets. Knowledge of importin function has expanded substantially in regard to three key developmental systems: embryonic stem cells, muscle cells and the germ line. In the decade since the potential for regulated nucleocytoplasmic transport to contribute to spermatogenesis was proposed, we and others have shown that the importins that ferry transcription factors into the nucleus perform additional roles, which control cell fate. This review presents key findings from studies of mammalian spermatogenesis that reveal potential new pathways by which male fertility and infertility arise. These studies of germline genesis illuminate new ways in which importin proteins govern cellular differentiation, including via directing proteins to distinct intracellular compartments and by determining cellular stress responses.

  14. Cell fate after mitotic arrest in different tumor cells is determined by the balance between slippage and apoptotic threshold

    Energy Technology Data Exchange (ETDEWEB)

    Galán-Malo, Patricia; Vela, Laura; Gonzalo, Oscar; Calvo-Sanjuán, Rubén; Gracia-Fleta, Lucía; Naval, Javier; Marzo, Isabel, E-mail: imarzo@unizar.es

    2012-02-01

    Microtubule poisons and other anti-mitotic drugs induce tumor death but the molecular events linking mitotic arrest to cell death are still not fully understood. We have analyzed cell fate after mitotic arrest produced by the microtubule-destabilizing drug vincristine in a panel of human tumor cell lines showing different response to vincristine. In Jurkat, RPMI 8226 and HeLa cells, apoptosis was triggered shortly after vincristine-induced mitotic arrest. However, A549 cells, which express a great amount of Bcl-x{sub L} and undetectable amounts of Bak, underwent mitotic slippage prior to cell death. However, when Bcl-x{sub L} gene was silenced in A549 cells, vincristine induced apoptosis during mitotic arrest. Another different behavior was found in MiaPaca2 cells, where vincristine caused death by mitotic catastrophe that switched to apoptosis when cyclin B1 degradation was prevented by proteasome inhibition. Overexpression of Bcl-x{sub L} or silencing Bax and Bak expression delayed the onset of apoptosis in Jurkat and RPMI 8226 cells, enabling mitotic slippage and endoreduplication. In HeLa cells, overexpression of Bcl-x{sub L} switched cell death from apoptosis to mitotic catastrophe. Mcl-1 offered limited protection to vincristine-induced cell death and Mcl-1 degradation was not essential for vincristine-induced death. All these results, taken together, indicate that the Bcl-x{sub L}/Bak ratio and the ability to degrade cyclin B1 determine cell fate after mitotic arrest in the different tumor cell types. Highlights: ► Vincristine induces cell death by apoptosis or mitotic catastrophe. ► Apoptosis-proficient cells die by apoptosis during mitosis upon vincristine treatment. ► p53wt apoptosis-deficient cells undergo apoptosis from a G1-like tetraploid state. ► p53mt apoptosis-deficient cells can survive and divide giving rise to 8N cells.

  15. Anti-Proliferative and Pro-Apoptotic Activities of 4-Methyl-2,6-bis(1-phenylethyl)phenol in Cancer Cells.

    Science.gov (United States)

    Sung, Nak Yoon; Kim, Seung Cheol; Kim, Yun Hwan; Kim, Gihyeon; Lee, Yunmi; Sung, Gi-Ho; Kim, Ji Hye; Yang, Woo Seok; Kim, Mi Seon; Baek, Kwang-Soo; Kim, Jong-Hoon; Cho, Jae Youl

    2016-07-01

    It has been found that 4-isopropyl-2,6-bis(1-phenylethyl)phenol (KTH-13), a novel compound isolated from Cordyceps bassiana, is able to suppress tumor cell proliferation by inducing apoptosis. To mass-produce this compound, we established a total synthesis method. Using those conditions, we further synthesized various analogs with structural similarity to KTH-13. In this study, we aimed to test their anti-cancer activity by measuring anti-proliferative and pro-apoptotic activities. Of 8 compounds tested, 4-methyl-2,6-bis(1-phenylethyl)phenol (KTH-13-Me) exhibited the strongest anti-proliferative activity toward MDA-MB 231 cells. KTH-13-Me also similarly suppressed the survival of various cancer cell lines, including C6 glioma, HCT-15, and LoVo cells. Treatment of KTH-13-Me induced several apoptotic signs in C6 glioma cells, such as morphological changes, induction of apoptotic bodies, and nuclear fragmentation and chromatin condensation. Concordantly, early-apoptotic cells were also identified by staining with FITC-Annexin V/PI. Moreover, KTH-13-Me highly enhanced the activation of caspase-3 and caspase-9, and decreased the protein level of Bcl-2. In addition, the phosphorylation levels of Src and STAT3 were diminished in KTH-13-Me-treated C6 cells. Therefore, these results suggest that KTH-13-Me can be developed as a novel anti-cancer drug capable of blocking proliferation, inducing apoptosis, and blocking cell survival signaling in cancer cells. PMID:27068261

  16. Dominant effects of Δ40p53 on p53 function and melanoma cell fate

    OpenAIRE

    Takahashi, Rie; Markovic, Svetomir; Scrable, Heidi

    2013-01-01

    The p53 gene encodes 12 distinct isoforms some of which can alter p53 activity in the absence of genomic alteration. Endogenous p53 isoforms have been identified in cancers; however, the function of these isoforms remains unclear. In melanoma, the frequency of p53 mutations is relatively low compared to other cancers suggesting that these isoforms may play a larger role in regulating p53 activity. We hypothesized that p53 function and therefore cell fate might be altered by the presence of Δ4...

  17. Estrogen receptor coregulators and pioneer factors: The orchestrators of mammary gland cell fate and development

    Directory of Open Access Journals (Sweden)

    Bramanandam eManavathi

    2014-08-01

    Full Text Available The 17-beta estradiol (E2, a steroid hormone, which play critical role in various cellular processes such as cell proliferation, differentiation, migration and apoptosis, is essential for reproduction and mammary gland development. E2 actions are mediated by two classical nuclear hormone receptors, estrogen receptor alpha and beta (ERs. The activity of ERs depends on the coordinate activity of ligand binding, posttranslational modification, and importantly their interaction with their partner proteins called ‘coregulators’. Because majority of breast cancers are ERalpha positive and coregulators are proved to be crucial for ER transcriptional activity, an increased interest in the field has led to the identification of a large number of coregulators. In the last decade, gene knockout studies using mouse models provided impetus to our further understanding of the role of these coregulators in mammary gland development. Several coregulators appear to be critical for terminal end bud formation, ductal branching and alveologenesis during mammary gland development. The emerging studies support that, in addition to these coregulators, the other ER partner proteins ‘pioneering factors’ also seems to contribute significantly to E2 signaling and mammary cell fate. This review discusses emerging themes in coregulator- and pioneering factor-mediated action on ER functions, particularly their role in mammary gland cell fate and development.

  18. Single-Cell Profiling of Epigenetic Modifiers Identifies PRDM14 as an Inducer of Cell Fate in the Mammalian Embryo

    Directory of Open Access Journals (Sweden)

    Adam Burton

    2013-11-01

    Full Text Available Cell plasticity or potency is necessary for the formation of multiple cell types. The mechanisms underlying this plasticity are largely unknown. Preimplantation mouse embryos undergo drastic changes in cellular potency, starting with the totipotent zygote through to the formation of the pluripotent inner cell mass (ICM and differentiated trophectoderm in the blastocyst. Here, we set out to identify and functionally characterize chromatin modifiers that define the transitions of potency and cell fate in the mouse embryo. Using a quantitative microfluidics approach in single cells, we show that developmental transitions are marked by distinctive combinatorial profiles of epigenetic modifiers. Pluripotent cells of the ICM are distinct from their differentiated trophectoderm counterparts. We show that PRDM14 is heterogeneously expressed in 4-cell-stage embryos. Forced expression of PRDM14 at the 2-cell stage leads to increased H3R26me2 and can induce a pluripotent ICM fate. Our results shed light on the epigenetic networks that govern cellular potency and identity in vivo.

  19. Early Cell Fate Decisions of Human Embryonic Stem Cells and Mouse Epiblast Stem Cells Are Controlled by the Same Signalling Pathways

    OpenAIRE

    Ludovic Vallier; Thomas Touboul; Zhenzhi Chng; Minodora Brimpari; Nicholas Hannan; Enrique Millan; Smithers, Lucy E.; Matthew Trotter; Peter Rugg-Gunn; Anne Weber; Pedersen, Roger A.

    2009-01-01

    Human embryonic stem cells have unique value for regenerative medicine, as they are capable of differentiating into a broad variety of cell types. Therefore, defining the signalling pathways that control early cell fate decisions of pluripotent stem cells represents a major task. Moreover, modelling the early steps of embryonic development in vitro may provide the best approach to produce cell types with native properties. Here, we analysed the function of key developmental growth factors suc...

  20. Determination of wing cell fate by the escargot and snail genes in Drosophila.

    Science.gov (United States)

    Fuse, N; Hirose, S; Hayashi, S

    1996-04-01

    Inset appendages such as the wing and the leg are formed in response to inductive signals in the embryonic field. In Drosophila, cells receiving such signals initiate developmental programs which allow them to become imaginal discs. Subsequently, these discs autonomously organize patterns specific for each appendage. We here report that two related transcription factors, Escargot and Snail that are expressed in the embryonic wing disc, function as intrinsic determinants of the wing cell fate. In escargot or snail mutant embryos, wing-specific expression of Snail, Vestigial and beta-galactosidase regulated by escargot enhancer were found as well as in wild-type embryos. However, in escargot snail double mutant embryos, wing development proceeded until stage 13, but the marker expression was not maintained in later stages, and the invagination of the primordium was absent. From such analyses, it was concluded that Escargot and Snail expression in the wing disc are maintained by their auto- and crossactivation. Ubiquitous escargot or snail expression induced from the hsp70 promoter rescued the escargot snail double mutant phenotype with the effects confined to the prospective wing cells. Similar DNA binding specificities of Escargot and Snail suggest that they control the same set of genes required for wing development. We thus propose the following scenario for early wing disc development. Prospective wing cells respond to the induction by turning on escargot and snail transcription, and become competent for regulation by Escargot and Snail. Such cells initiate auto- and crossregulatory circuits of escargot and snail. The sustained Escargot and Snail expression then activates vestigial and other target genes that are essential for wing development. This maintains the commitment to the wing cell fate and induces wing-specific cell shape change. PMID:8620833

  1. Gene Regulatory Network Analysis Reveals Differences in Site-specific Cell Fate Determination in Mammalian Brain

    Directory of Open Access Journals (Sweden)

    Gokhan eErtaylan

    2014-12-01

    Full Text Available Neurogenesis - the generation of new neurons - is an ongoing process that persists in the adult mammalian brain of several species, including humans. In this work we analyze two discrete brain regions: the subventricular zone (SVZ lining the walls of the lateral ventricles; and the subgranular zone (SGZ of the dentate gyrus of the hippocampus in mice and shed light on the SVZ and SGZ specific neurogenesis. We propose a computational model that relies on the construction and analysis of region specific gene regulatory networks from the publicly available data on these two regions. Using this model a number of putative factors involved in neuronal stem cell (NSC identity and maintenance were identified. We also demonstrate potential gender and niche-derived differences based on cell surface and nuclear receptors via Ar, Hif1a and Nr3c1.We have also conducted cell fate determinant analysis for SVZ NSC populations to Olfactory Bulb interneurons and SGZ NSC populations to the granule cells of the Granular Cell Layer. We report thirty-one candidate cell fate determinant gene pairs, ready to be validated. We focus on Ar - Pax6 in SVZ and Sox2 - Ncor1 in SGZ. Both pairs are expressed and localized in the suggested anatomical structures as shown by in situ hybridization and found to physically interact.Finally, we conclude that there are fundamental differences between SGZ and SVZ neurogenesis. We argue that these regulatory mechanisms are linked to the observed differential neurogenic potential of these regions. The presence of nuclear and cell surface receptors in the region specific regulatory circuits indicate the significance of niche derived extracellular factors, hormones and region specific factors such as the oxygen sensitivity, dictating SGZ and SVZ specific neurogenesis.

  2. Differentially activated macrophages orchestrate myogenic precursor cell fate during human skeletal muscle regeneration

    DEFF Research Database (Denmark)

    Saclier, Marielle; Yacoub-Youssef, Houda; Mackey, Abigail;

    2013-01-01

    Macrophages (MPs) exert either beneficial or deleterious effects on tissue repair, depending on their activation/polarization state. They are crucial for adult skeletal muscle repair, notably by acting on myogenic precursor cells. However, these interactions have not been fully characterized. Here......, we explored both in vitro and in vivo, in human, the interactions of differentially activated MPs with myogenic precursor cells (MPCs) during adult myogenesis and skeletal muscle regeneration. We showed in vitro that through the differential secretion of cytokines and growth factors, proinflammatory...... anti-inflammatory markers. These data demonstrate for the first time in human that MPs sequentially orchestrate adult myogenesis during regeneration of damaged skeletal muscle. These results support the emerging concept that inflammation, through MP activation, controls stem cell fate and coordinates...

  3. Genetic control of murine T cell proliferative responses to Mycobacterium leprae. V. Evidence for cross-reactivity between host antigens and Mycobacterium leprae

    International Nuclear Information System (INIS)

    T cell proliferative responses to Mycobacterium leprae were measured by immunization of mice at the base of the tail with Ag and challenging lymphocytes from draining lymph nodes in culture with M. leprae. C57BL/10J and B10.BR mice were identified as low responder mice and the congenic strains B10.M, B10.Q, and B10.AKM as high responders whereas F1 (high x low) hybrid mice were found to be low responders. The cellular basis of low responsiveness did not appear to result from a defect in Ag-presenting cells or the activation of suppressor T cells by M. leprae. The influence of the environment in which T cells developed on responsiveness to M. leprae was analyzed in chimeric mice prepared by irradiating F1(C57BL/10J x B10.M) mice and reconstituting with bone marrow from C57BL/10J, B10.M, or F1 donors. Six weeks later, chimeric mice were immunized with M. leprae, lymph node cells were subsequently prepared, and H-2 phenotyped and challenged in culture with M. leprae Ag. T cell proliferative responses were found to be low in all cases, similar to those observed using lymph node cells from F1 hybrid mice. These results suggested that high responder B10.M lymphocytes developing in the irradiated F1 mice became tolerized to antigenic determinants found on M. leprae. This implied cross-reactive epitopes existed between some mouse strains and M. leprae. Low responsiveness to M. leprae in low responder and F1 hybrid mice may result from tolerance to H-2-encoded Ag that show cross-reactivity with M. leprae

  4. DMPD: Nitric oxide and cell viability in inflammatory cells: a role for NO inmacrophage function and fate. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15691589 Nitric oxide and cell viability in inflammatory cells: a role for NO inmac...(.png) (.svg) (.html) (.csml) Show Nitric oxide and cell viability in inflammatory cells: a role for NO inma...ty in inflammatory cells: a role for NO inmacrophage function and fate. Authors Bosca L, Zeini M, Traves PG,

  5. The fate of chrysotile-induced multipolar mitosis and aneuploid population in cultured lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Beatriz de Araujo Cortez

    Full Text Available Chrysotile is one of the six types of asbestos, and it is the only one that can still be commercialized in many countries. Exposure to other types of asbestos has been associated with serious diseases, such as lung carcinomas and pleural mesotheliomas. The association of chrysotile exposure with disease is controversial. However, in vitro studies show the mutagenic potential of chrysotile, which can induce DNA and cell damage. The present work aimed to analyze alterations in lung small cell carcinoma cultures after 48 h of chrysotile exposure, followed by 2, 4 and 8 days of recovery in fiber-free culture medium. Some alterations, such as aneuploid cell formation, increased number of cells in G2/M phase and cells in multipolar mitosis were observed even after 8 days of recovery. The presence of chrysotile fibers in the cell cultures was detected and cell morphology was observed by laser scanning confocal microscopy. After 4 and 8 days of recovery, only a few chrysotile fragments were present in some cells, and the cellular morphology was similar to that of control cells. Cells transfected with the GFP-tagged α-tubulin plasmid were treated with chrysotile for 24 or 48 h and cells in multipolar mitosis were observed by time-lapse microscopy. Fates of these cells were established: retention in metaphase, cell death, progression through M phase generating more than two daughter cells or cell fusion during telophase or cytokinesis. Some of them were related to the formation of aneuploid cells and cells with abnormal number of centrosomes.

  6. Thickness sensing of hMSCs on collagen gel directs stem cell fate

    International Nuclear Information System (INIS)

    Research highlights: → hMSCs appeared to sense thin collagen gel (130 μm) with higher effective modulus as compared to thick gel (1440 μm). → Control of collagen gel thickness can modulate cellular behavior, even stem cell fate (neuronal vs. Quiescent). → Distinct cellular behavior of hMSCs on thin and thick collagen gel suggests long range interaction of hMSCs with collagen gel. -- Abstract: Mechanically compliant substrate provides crucial biomechanical cues for multipotent stem cells to regulate cellular fates such as differentiation, proliferation and maintenance of their phenotype. Effective modulus of which cells sense is not only determined by intrinsic mechanical properties of the substrate, but also the thickness of substrate. From our study, it was found that interference from underlying rigid support at hundreds of microns away could induce significant cellular response. Human mesenchymal stem cells (hMSCs) were cultured on compliant biological gel, collagen type I, of different thickness but identical ECM composition and local stiffness. The cells sensed the thin gel (130 μm) as having a higher effective modulus than the thick gel (1440 μm) and this was reflected in their changes in morphology, actin fibers structure, proliferation and tissue specific gene expression. Commitment into neuronal lineage was observed on the thin gel only. Conversely, the thick gel (1440 μm) was found to act like a substrate with lower effective modulus that inhibited actin fiber polymerization. Stem cells on the thick substrate did not express tissue specific genes and remained at their quiescent state. This study highlighted the need to consider not only the local modulus but also the thickness of biopolymer gel coating during modulation of cellular responses.

  7. β-Catenin Signaling Biases Multipotent Lingual Epithelial Progenitors to Differentiate and Acquire Specific Taste Cell Fates.

    Directory of Open Access Journals (Sweden)

    Dany Gaillard

    2015-05-01

    Full Text Available Continuous taste bud cell renewal is essential to maintain taste function in adults; however, the molecular mechanisms that regulate taste cell turnover are unknown. Using inducible Cre-lox technology, we show that activation of β-catenin signaling in multipotent lingual epithelial progenitors outside of taste buds diverts daughter cells from a general epithelial to a taste bud fate. Moreover, while taste buds comprise 3 morphological types, β-catenin activation drives overproduction of primarily glial-like Type I taste cells in both anterior fungiform (FF and posterior circumvallate (CV taste buds, with a small increase in Type II receptor cells for sweet, bitter and umami, but does not alter Type III sour detector cells. Beta-catenin activation in post-mitotic taste bud precursors likewise regulates cell differentiation; forced activation of β-catenin in these Shh+ cells promotes Type I cell fate in both FF and CV taste buds, but likely does so non-cell autonomously. Our data are consistent with a model where β-catenin signaling levels within lingual epithelial progenitors dictate cell fate prior to or during entry of new cells into taste buds; high signaling induces Type I cells, intermediate levels drive Type II cell differentiation, while low levels may drive differentiation of Type III cells.

  8. The neural stem cell fate determinant TRIM32 regulates complex behavioral traits

    Directory of Open Access Journals (Sweden)

    Anna-Lena eHillje

    2015-03-01

    Full Text Available In mammals, new neurons are generated throughout the entire lifespan in two restricted areas of the brain, the dentate gyrus (DG of the hippocampus and the subventricular zone (SVZ – olfactory bulb (OB system. In both regions newborn neurons display unique properties that clearly distinguish them from mature neurons. Enhanced excitability and increased synaptic plasticity enables them to add specific properties to information processing by modulating the existing local circuitry of already established mature neurons. Hippocampal neurogenesis has been suggested to play a role in spatial-navigation learning, spatial memory and spatial pattern separation. Cumulative evidences implicate that adult-born OB neurons contribute to learning processes and odor memory. We recently demonstrated that the cell fate determinant TRIM32 is upregulated in differentiating neuroblasts of the SVZ-OB system in the adult mouse brain. The absence of TRIM32 leads to increased progenitor cell proliferation and less cell death. Both effects accumulate in an overproduction of adult-generated OB neurons. Here, we present novel data from behavioral studies showing that such an enhancement of OB neurogenesis not necessarily leads to increased olfactory performance but in contrast even results in impaired olfactory capabilities. In addition, we show at the cellular level that TRIM32 protein levels increase during differentiation of neural stem cells. At the molecular level, several metabolic intermediates that are connected to glycolysis, glycine or cysteine metabolism are deregulated in TRIM32 knockout mice brain tissue. These metabolomics pathways are directly or indirectly linked to anxiety or depression like behavior. In summary, our study provides comprehensive data on how the impairment of neurogenesis caused by the loss of the cell fate determinant TRIM32 causes a decrease of olfactory performance as well as a deregulation of metabolomic pathways that are linked to

  9. Bar represses dPax2 and decapentaplegic to regulate cell fate and morphogenetic cell death in Drosophila eye.

    Directory of Open Access Journals (Sweden)

    Jongkyun Kang

    Full Text Available The coordinated regulation of cell fate and cell survival is crucial for normal pattern formation in developing organisms. In Drosophila compound eye development, crystalline arrays of hexagonal ommatidia are established by precise assembly of diverse cell types, including the photoreceptor cells, cone cells and interommatidial (IOM pigment cells. The molecular basis for controlling the number of cone and IOM pigment cells during ommatidial pattern formation is not well understood. Here we present evidence that BarH1 and BarH2 homeobox genes are essential for eye patterning by inhibiting excess cone cell differentiation and promoting programmed death of IOM cells. Specifically, we show that loss of Bar from the undifferentiated retinal precursor cells leads to ectopic expression of Prospero and dPax2, two transcription factors essential for cone cell specification, resulting in excess cone cell differentiation. We also show that loss of Bar causes ectopic expression of the TGFβ homolog Decapentaplegic (Dpp posterior to the morphogenetic furrow in the larval eye imaginal disc. The ectopic Dpp expression is not responsible for the formation of excess cone cells in Bar loss-of-function mutant eyes. Instead, it causes reduction in IOM cell death in the pupal stage by antagonizing the function of pro-apoptotic gene reaper. Taken together, this study suggests a novel regulatory mechanism in the control of developmental cell death in which the repression of Dpp by Bar in larval eye disc is essential for IOM cell death in pupal retina.

  10. Ascl1b and Neurod1, instead of Neurog3, control pancreatic endocrine cell fate in zebrafish

    OpenAIRE

    Flasse, Lydie; Pirson, Justine; Stern, David,; Von Berg, Virginie; Manfroid, Isabelle; Peers, Bernard; Voz, Marianne

    2013-01-01

    Background NEUROG3 is a key regulator of pancreatic endocrine cell differentiation in mouse, essential for the generation of all mature hormone producing cells. It is repressed by Notch signaling that prevents pancreatic cell differentiation by maintaining precursors in an undifferentiated state. Results We show that, in zebrafish, neurog3 is not expressed in the pancreas and null neurog3 mutant embryos do not display any apparent endocrine defects. The control of endocrine cell fate is inste...

  11. Synthesis, characterization, anti-inflammatory and anti-proliferative activity against MCF-7 cells of O-alkyl and O-acyl flavonoid derivatives.

    Science.gov (United States)

    Hoang, T Kim-Dung; Huynh, T Kim-Chi; Nguyen, Thanh-Danh

    2015-12-01

    A series of O-alkyl and O-acyl flavonoid derivatives was synthesized in high efficiency. Alkylation and acylation of 5-hydroxyflavonoids showed that the low reactivity hydroxyl group, 5-OH, well reacted with strong reagents whereas with weaker reagents, the different products were obtained dependently on structural characteristic of ring C of respective flavonoid. In order to evaluate anti-inflammatory activity, all compounds were tested for in vitro inhibition of bovine serum albumin denaturation and in vivo inhibition of carrageenan-induced mouse paw edema. Among them, the compounds 3, 3b, 4b and 4c demonstrated more effective anti-inflammatory activity than standard drugs (diclofenac sodium and ketoprofen) in both tests. Meanwhile, the flavonoids 2, 2c, 3a and 4b displayed anti-proliferative activity against MCF-7 cell lines. Triacetyl derivative of hesperetin 4b inducing degradation of DNA in MCF-7 cells was observed. PMID:26432615

  12. Interplay of Notch and FGF signaling restricts cell fate and MAPK activation in the Drosophila trachea.

    Science.gov (United States)

    Ikeya, T; Hayashi, S

    1999-10-01

    The patterned branching in the Drosophila tracheal system is triggered by the FGF-like ligand Branchless that activates a receptor tyrosine kinase Breathless and the MAP kinase pathway. A single fusion cell at the tip of each fusion branch expresses the zinc-finger gene escargot, leads branch migration in a stereotypical pattern and contacts with another fusion cell to mediate fusion of the branches. A high level of MAP kinase activation is also limited to the tip of the branches. Restriction of such cell specialization events to the tip is essential for tracheal tubulogenesis. Here we show that Notch signaling plays crucial roles in the singling out process of the fusion cell. We found that Notch is activated in tracheal cells by Branchless signaling through stimulation of &Dgr; expression at the tip of tracheal branches and that activated Notch represses the fate of the fusion cell. In addition, Notch is required to restrict activation of MAP kinase to the tip of the branches, in part through the negative regulation of Branchless expression. Notch-mediated lateral inhibition in sending and receiving cells is thus essential to restrict the inductive influence of Branchless on the tracheal tubulogenesis. PMID:10498681

  13. A fungicide-responsive kinase as a tool for synthetic cell fate regulation.

    Science.gov (United States)

    Furukawa, Kentaro; Hohmann, Stefan

    2015-08-18

    Engineered biological systems that precisely execute defined tasks have major potential for medicine and biotechnology. For instance, gene- or cell-based therapies targeting pathogenic cells may replace time- and resource-intensive drug development. Engineering signal transduction systems is a promising, yet presently underexplored approach. Here, we exploit a fungicide-responsive heterologous histidine kinase for pathway engineering and synthetic cell fate regulation in the budding yeast Saccharomyces cerevisiae. Rewiring the osmoregulatory Hog1 MAPK signalling system generates yeast cells programmed to execute three different tasks. First, a synthetic negative feedback loop implemented by employing the fungicide-responsive kinase and a fungicide-resistant derivative reshapes the Hog1 activation profile, demonstrating how signalling dynamics can be engineered. Second, combinatorial integration of different genetic parts including the histidine kinases, a pathway activator and chemically regulated promoters enables control of yeast growth and/or gene expression in a two-input Boolean logic manner. Finally, we implemented a genetic 'suicide attack' system, in which engineered cells eliminate target cells and themselves in a specific and controllable manner. Taken together, fungicide-responsive kinases can be applied in different constellations to engineer signalling behaviour. Sensitizing engineered cells to existing chemicals may be generally useful for future medical and biotechnological applications. PMID:26138483

  14. A peroxisome proliferator-activated receptor ligand MCC-555 imparts anti-proliferative response in pancreatic cancer cells by PPARgamma-independent up-regulation of KLF4

    International Nuclear Information System (INIS)

    MCC-555 is a novel PPARα/γ dual ligand of the thiazolidinedione class and was recently developed as an anti-diabetic drug with unique properties. MCC-555 also has anti-proliferative activity through growth inhibition and apoptosis induction in several cancer cell types. Our group has shown that MCC-555 targets several proteins in colorectal tumorigenesis including nonsteroidal anti-inflammatory drug (NSAID)-activated gene (NAG-1) which plays an important role in chemoprevention responsible for chemopreventive compounds. NAG-1 is a member of the TGF-β superfamily and is involved in tumor progression and development; however, NAG-1's roles in pancreatic cancer have not been studied. In this report, we found that MCC-555 alters not only NAG-1 expression, but also p21 and cyclin D1 expression. NAG-1 and p21 expression was not blocked by PPARγ-specific antagonist GW9662, suggesting that MCC-555-induced NAG-1 and p21 expression is independent of PPARγ activation. However, decreasing cyclin D1 by MCC-555 seems to be affected by PPARγ activation. Further, we found that the GC box located in the NAG-1 promoter play an important role in NAG-1 transactivation by MCC-555. Subsequently, we screened several transcription factors that may bind to the GC box region in the NAG-1 promoter and found that KLF4 potentially binds to this region. Expression of KLF4 precedes NAG-1 and p21 expression in the presence of MCC-555, whereas blocking KLF4 expression using specific KLF4 siRNA showed that both NAG-1 and p21 expression by MCC-555 was blocked. In conclusion, MCC-555's actions on anti-proliferation involve both PPARγ-dependent and -independent pathways, thereby enhancing anti-tumorigenesis in pancreatic cancer cells. -- Highlights: ► PPARα/γ ligand MCC-555 exhibits anti-proliferative activity in pancreatic cancer cells. ► MCC-555 affects KLF4 expression following by NAG-1 and p21 expression in a PPARγ independent manner. ► MCC-555 also affects cyclin D1 down

  15. The neural crest stem cells: control of neural crest cell fate and plasticity by endothelin-3

    Directory of Open Access Journals (Sweden)

    ELISABETH DUPIN

    2001-12-01

    Full Text Available How the considerable diversity of neural crest (NC-derived cell types arises in the vertebrate embryo has long been a key question in developmental biology. The pluripotency and plasticity of differentiation of the NC cell population has been fully documented and it is well-established that environmental cues play an important role in patterning the NC derivatives throughout the body. Over the past decade, in vivo and in vitro cellular approaches have unravelled the differentiation potentialities of single NC cells and led to the discovery of NC stem cells. Although it is clear that the final fate of individual cells is in agreement with their final position within the embryo, it has to be stressed that the NC cells that reach target sites are pluripotent and further restrictions occur only late in development. It is therefore a heterogenous collection of cells that is submitted to local environmental signals in the various NC-derived structures. Several factors were thus identified which favor the development of subsets of NC-derived cells in vitro. Moreover, the strategy of gene targeting in mouse has led at identifying new molecules able to control one or several aspects of NC cell differentiation in vivo. Endothelin peptides (and endothelin receptors are among those. The conjunction of recent data obtained in mouse and avian embryos and reviewed here contributes to a better understanding of the action of the endothelin signaling pathway in the emergence and stability of NC-derived cell phenotypes.O modo como a diversidade dos tipos celulares derivados da crista neural (CN surge, no embrião de vertebrado, tem sido uma pergunta chave na biologia do desenvolvimento. A pluripotência e a plasticidade na diferenciação da população de células da CN têm sido intensivamente documentadas, ficando deste modo estabelecido que os factores ambientais têm um papel importante na correta diferenciação dos derivados da CN no organismo. Na d

  16. Association between Tumorigenic Potential and the Fate of Cancer Cells in a Syngeneic Melanoma Model

    Science.gov (United States)

    Krelin, Yakov; Berkovich, Liron; Amit, Moran; Gil, Ziv

    2013-01-01

    The self-renewal potential of a cancer cell can be estimated by using particular assays, which include xenotransplantation in immunocompromised animals or culturing in non-adherent serum-free stem-cells media (SCM). However, whether cells with self-renewal potential actually contribute to disease is unknown. Here we investigated the tumorigenic potential and fate of cancer cells in an in-vivo melanoma model. We examined cell lines which were derived from the same parental line: a non-metastatic cell line (K1735/16), a metastatic cell line (K1735/M4) and a cell line which was selected in non-adherent conditions (K1735/16S). All cell lines exhibited similar proliferation kinetics when grown on culture plates. K1735/16 cells grown in soft agar or in suspension non-adherent conditions failed to form colonies or spheroids, whereas the other cell lines showed prominent colonogenicity and spheroid formation capacity. By using sphere limiting dilution analysis (SLDA) in serum-free media, K1735/16S and K1735/M4 cells grown in suspension were capable of forming spheroids even in low frequencies of concentrations, as opposed to K1735/16 cells. The tumorigenic potential of the cell lines was determined in SCID mice using intra footpad injections. Palpable tumors were evident in all mice. In agreement with the in-vitro studies, the K1735/M4 cell line exhibited the highest growth kinetics, followed by the K1735/16S cell line, whereas the K1735/16 cell line had the lowest tumor growth potential (P<0.001). In contrast, when we repeated the experiments in syngeneic C3H/HeN mice, the K1735/16 cell line produced macroscopic tumors 30–100 days after injection, whereas K1735/M4 and K1735/16S derived tumors regressed spontaneously in 90–100% of mice. TUNEL analysis revealed significantly higher number of apoptotic cells in K1735/16S and K1735/M4 cell line-derived tumors compared to K1735/16 tumors (P<0.001). The models we have examined here raised the possibility, that cells with

  17. Forced expression of Hnf1b/Foxa3 promotes hepatic fate of embryonic stem cells.

    Science.gov (United States)

    Yahoo, Neda; Pournasr, Behshad; Rostamzadeh, Jalal; Hakhamaneshi, Mohammad Saeed; Ebadifar, Asghar; Fathi, Fardin; Baharvand, Hossein

    2016-05-20

    Embryonic stem (ES) cell-derived hepatocytes have the potential to be used for basic research, regenerative medicine, and drug discovery. Recent reports demonstrated that in addition to conventional differentiation inducers such as chemical compounds and cytokines, overexpression of lineage-specific transcription factors could induce ES cells to differentiate to a hepatic fate. Here, we hypothesized that lentivirus-mediated inducible expression of hepatic lineage transcription factors could enhance mouse ES cells to hepatocyte-like cells. We screened the effects of candidate transcription factors Hnf1b, Hnf1a, Hnf4a, Foxa1, Foxa3 and Hex, and determined that the combination of Hnf1b/Foxa3 promoted expression of several hepatic lineage-specific markers and proteins, in addition to glycogen storage, ICG uptake, and secretion of albumin and urea. The differentiated cells were engraftable and expressed albumin when transplanted into a carbon tetrachloride-injured mouse model. These results demonstrated the crucial role of Hnf1b and Foxa3 in hepatogenesis in vitro and provided a valuable tool for the efficient differentiation of HLCs from ES cells. PMID:27107701

  18. Role of VDR in anti-proliferative effects of calcitriol in tumor-derived endothelial cells and tumor angiogenesis in vivo

    Science.gov (United States)

    Chung, Ivy; Han, Guangzhou; Seshadri, Mukund; Gillard, Bryan M.; Yu, Wei-dong; Foster, Barbara A.; Trump, Donald L.; Johnson, Candace S.

    2008-01-01

    Calcitriol (1, 25-dihydroxycholecalciferol), the major active form of vitamin D, is anti-proliferative in tumor cells and tumor-derived endothelial cells (TDEC). These actions of calcitriol are mediated at least in part by vitamin D receptor (VDR), which is expressed in many tissues including endothelial cells. To investigate the role of VDR in calcitriol effects on tumor vasculature, we established TRAMP-2 tumors subcutaneously into either VDR wild type (WT) or knockout (KO) mice. Within 30 days post inoculation, tumors in KO mice were larger than those in WT (P<0.001). TDEC from WT expressed VDR and were able to transactivate a reporter gene whereas TDEC from KO mice were not. Treatment with calcitriol resulted in growth inhibition in TDEC expressing VDR. However, TDEC from KO mice were relatively resistant, suggesting that calcitriol-mediated growth inhibition on TDEC is VDR-dependent. Further analysis of the TRAMP-C2 tumor sections revealed that the vessels in KO mice were enlarged and had less pericyte coverage compared to WT (P<0.001). Contrast-enhanced MRI demonstrated an increase in vascular volume of TRAMP tumors grown in VDR KO mice compared to WT mice (P<0.001) and FITC-dextran permeability assay suggested a higher extent of vascular leakage in tumors from KO mice. Using ELISA and Western blot analysis, there was an increase of HIF-1 alpha, VEGF, Ang1 and PDGF-BB levels observed in tumors from KO mice. These results indicate that calcitriol-mediated anti-proliferative effects on TDEC are VDR dependent and loss of VDR can lead to abnormal tumor angiogenesis. PMID:19141646

  19. The CLAVATA signaling pathway mediating stem cell fate in shoot meristems requires Ca(2+) as a secondary cytosolic messenger.

    Science.gov (United States)

    Chou, Hsuan; Zhu, Yingfang; Ma, Yi; Berkowitz, Gerald A

    2016-02-01

    CLAVATA1 (CLV1) is a receptor protein expressed in the shoot apical meristem (SAM) that translates perception of a non-cell-autonomous CLAVATA3 (CLV3) peptide signal into altered stem cell fate. CLV3 reduces expression of WUSCHEL (WUS) and FANTASTIC FOUR 2 (FAF2) in the SAM. Expression of WUS and FAF2 leads to maintenance of undifferentiated stem cells in the SAM. CLV3 binding to CLV1 inhibits expression of these genes and controls stem cell fate in the SAM through an unidentified signaling pathway. Cytosolic Ca(2+) elevations, cyclic nucleotide (cGMP)-activated Ca(2+) channels, and cGMP have been linked to signaling downstream of receptors similar to CLV1. Hence, we hypothesized that cytosolic Ca(2+) elevation mediates the CLV3 ligand/CLV1 receptor signaling that controls meristem stem cell fate. CLV3 application to Arabidopsis seedlings results in elevation of cytosolic Ca(2+) and cGMP. CLV3 control of WUS was prevented in a genotype lacking a functional cGMP-activated Ca(2+) channel. In wild-type plants, CLV3 inhibition of WUS and FAF2 expression was impaired by treatment with either a Ca(2+) channel blocker or a guanylyl cyclase inhibitor. When CLV3-dependent repression of WUS is blocked, altered control of stem cell fate leads to an increase in SAM size; we observed a larger SAM size in seedlings treated with the Ca(2+) channel blocker. These results suggest that the CLV3 ligand/CLV1 receptor system initiates a signaling cascade that elevates cytosolic Ca(2+) , and that this cytosolic secondary messenger is involved in the signal transduction cascade linking CLV3/CLV1 to control of gene expression and stem cell fate in the SAM. PMID:26756833

  20. Asymmetric Localization of Cdx2 mRNA during the First Cell-Fate Decision in Early Mouse Development

    Directory of Open Access Journals (Sweden)

    Maria Skamagki

    2013-02-01

    Full Text Available A longstanding question in mammalian development is whether the divisions that segregate pluripotent progenitor cells for the future embryo from cells that differentiate into extraembryonic structures are asymmetric in cell-fate instructions. The transcription factor Cdx2 plays a key role in the first cell-fate decision. Here, using live-embryo imaging, we show that localization of Cdx2 transcripts becomes asymmetric during development, preceding cell lineage segregation. Cdx2 transcripts preferentially localize apically at the late eight-cell stage and become inherited asymmetrically during divisions that set apart pluripotent and differentiating cells. Asymmetric localization depends on a cis element within the coding region of Cdx2 and requires cell polarization as well as intact microtubule and actin cytoskeletons. Failure to enrich Cdx2 transcripts apically results in a significant decrease in the number of pluripotent cells. We discuss how the asymmetric localization and segregation of Cdx2 transcripts could contribute to multiple mechanisms that establish different cell fates in the mouse embryo.

  1. [Proliferative verrucous leukoplakia].

    Science.gov (United States)

    Lindenmüller, Irène Hitz; Lambrecht, J Thomas

    2006-01-01

    Proliferative verrucous leukoplakia (PVL) is a seldom form of oral leukoplakia (OL) with high transformation tendency. It starts as a bold hyperkeratosis changing into an exophytic verrucous form spreading in the oral cavity. The clinical diagnosis therefore is a retrospective one. PMID:16792055

  2. Proliferative retinopathy predicts nephropathy

    DEFF Research Database (Denmark)

    Karlberg, Charlotte; Falk, Christine; Green, Anders;

    2012-01-01

    We wanted to examine proliferative retinopathy as a marker of incident nephropathy in a 25-year follow-up study of a population-based cohort of Danish type 1 diabetic patients and to examine cross-sectional associations between nephropathy and retinopathy in long-term surviving patients of the sa...

  3. Tracing Conidial Fate and Measuring Host Cell Antifungal Activity Using a Reporter of Microbial Viability in the Lung

    OpenAIRE

    Jhingran, Anupam; Mar, Katrina B.; Kumasaka, Debra K.; Sue E Knoblaugh; Ngo, Lisa Y.; Segal, Brahm H; Iwakura, Yoichiro; Lowell, Clifford A.; Hamerman, Jessica A.; Lin, Xin; Tobias M Hohl

    2012-01-01

    Fluorescence can be harnessed to monitor microbial fate and to investigate functional outcomes of individual microbial cell-host cell encounters at portals of entry in native tissue environments. We illustrate this concept by introducing fluorescent Aspergillus reporter (FLARE) conidia that simultaneously report phagocytic uptake and fungal viability during cellular interactions with the murine respiratory innate immune system. Our studies using FLARE conidia reveal stepwise and cell-type-spe...

  4. Stimulative Effects of Low Intensity He-Ne Laser Irradiation on the Proliferative Potential and Cell-Cycle Progression of Myoblasts in Culture

    Directory of Open Access Journals (Sweden)

    Cui-Ping Zhang

    2014-01-01

    Full Text Available Low intensity laser irradiation (LILI was found to promote the regeneration of skeletal muscle in vivo but the cellular mechanisms are not fully understood. Myoblasts, normally quiescent and inactivated in adult skeletal muscle, are a type of myogenic progenitor cells and considered as the major candidates responsible for muscle regeneration. The aim of the present study was to study the effect of LILI on the growth potential and cell-cycle progression of the cultured myoblasts. Primary myoblasts isolated from rat hind legs were cultured in nutrient-deficient medium for 36 hours and then irradiated by helium-neon laser at a certain energy density. Immunohistochemical and flow cytometric analysis revealed that laser irradiation could increase the expression of cellular proliferation marker and the amount of cell subpopulations in the proliferative phase as compared with the nonirradiated control group. Meanwhile, the expressions of cell-cycle regulatory proteins in the laser-treated myoblasts were markedly upregulated as compared to the unirradiated cells, indicating that LILI could promote the reentry of quiescent myoblasts into the cell division cycle. These results suggest that LILI at certain fluences could promote their proliferation, thus contributing to the skeletal muscle regeneration following trauma and myopathic diseases.

  5. Proliferative retinopathies: animal models and therapeutic opportunities.

    Science.gov (United States)

    Villacampa, Pilar; Haurigot, Virginia; Bosch, Fatima

    2015-01-01

    Proliferative retinopathies are the leading causes of blindness in Western societies. The development of new, more efficacious treatments that take advantage of recent advances in the fields of gene and cell therapy requires further investigations on the mechanisms underlying disease onset and progression, and adequate animal models that recapitulate the pathogenesis of human proliferative retinopathy and allow evaluation of the long-term therapeutic benefits that these therapies can offer. Unfortunately, most models of retinal neovascularization have short-term evolution and diabetic rodents show a very mild retinal phenotype, limited to non-proliferative changes, and do not develop proliferative retinopathy at all. Transgenic mice overexpressing Insulin-like Growth Factor-I (IGF-I) in the retina (TgIGF-I) constitute the only rodent model currently available that develops most of the retinal alterations observed in diabetic eyes, with a temporal evolution that resembles that of the human disease. TgIGF-I have retinal vascular alterations that progress as animals age from non-proliferative to proliferative disease, making these mice an excellent model of proliferative retinopathy that, due to its slow progression, allows long-term evaluation of novel antiangiogenic therapies. At the molecular level, transgenic retinas recapitulate a variety of changes that are also observed in diabetic retinas, which reinforces the validity of this model. In addition to vascular and glial alterations, Tg-IGF-I mice show progressive neurodegeneration that leads to blindness in old animals. Thus, TgIGF-I are a useful model for testing the long-term efficacy and safety of innovative antiangiogenic, glial-modulating and neuroprotective therapies for the treatment of diabetic retinopathy and other retinal proliferative disorders. PMID:25760215

  6. Antigen availability determines CD8⁺ T cell-dendritic cell interaction kinetics and memory fate decisions.

    Science.gov (United States)

    Henrickson, Sarah E; Perro, Mario; Loughhead, Scott M; Senman, Balimkiz; Stutte, Susanne; Quigley, Michael; Alexe, Gabriela; Iannacone, Matteo; Flynn, Michael P; Omid, Shaida; Jesneck, Jonathan L; Imam, Sabrina; Mempel, Thorsten R; Mazo, Irina B; Haining, W Nicholas; von Andrian, Ulrich H

    2013-09-19

    T cells are activated by antigen (Ag)-bearing dendritic cells (DCs) in lymph nodes in three phases. The duration of the initial phase of transient, serial DC-T cell interactions is inversely correlated with Ag dose. The second phase, characterized by stable DC-T cell contacts, is believed to be necessary for full-fledged T cell activation. Here we have shown that this is not the case. CD8⁺ T cells interacting with DCs presenting low-dose, short-lived Ag did not transition to phase 2, whereas higher Ag dose yielded phase 2 transition. Both antigenic constellations promoted T cell proliferation and effector differentiation but yielded different transcriptome signatures at 12 hr and 24 hr. T cells that experienced phase 2 developed long-lived memory, whereas conditions without stable contacts yielded immunological amnesia. Thus, T cells make fate decisions within hours after Ag exposure, resulting in long-term memory or abortive effector responses, correlating with T cell-DCs interaction kinetics. PMID:24054328

  7. Multiple bidirectional alterations of phenotype and changes in proliferative potential during the in vitro and in vivo passage of clonal mast cell populations derived from mouse peritoneal mast cells

    Energy Technology Data Exchange (ETDEWEB)

    Kanakura, Y.; Thompson, H.; Nakano, T.; Yamamura, T.; Asai, H.; Kitamura, Y.; Metcalfe, D.D.; Galli, S.J.

    1988-09-01

    Mouse peritoneal mast cells (PMC) express a connective tissue-type mast cell (CTMC) phenotype, including reactivity with the heparin-binding fluorescent dye berberine sulfate and incorporation of (35S) sulfate predominantly into heparin proteoglycans. When PMC purified to greater than 99% purity were cultured in methylcellulose with IL-3 and IL-4, approximately 25% of the PMC formed colonies, all of which contained both berberine sulfate-positive and berberine sulfate-negative mast cells. When these mast cells were transferred to suspension culture, they generated populations that were 100% berberine sulfate-negative, a characteristic similar to that of mucosal mast cells (MMC), and that synthesized predominantly chondroitin sulfate (35S) proteoglycans. When ''MMC-like'' cultured mast cells derived from WBB6F1-+/+ PMC were injected into the peritoneal cavities of mast cell-deficient WBB6F1-W/Wv mice, the adoptively transferred mast cell population became 100% berberine sulfate-positive. In methylcellulose culture, these ''second generation PMC'' formed clonal colonies containing both berberine sulfate-positive and berberine sulfate-negative cells, but exhibited significantly less proliferative ability than did normal +/+ PMC. Thus, clonal mast cell populations initially derived from single PMC exhibited multiple and bidirectional alterations between CTMC-like and MMC-like phenotypes. However, this process was associated with a progressive diminution of the mast cells' proliferative ability.

  8. MicroRNA-126–mediated control of cell fate in B-cell myeloid progenitors as a potential alternative to transcriptional factors

    OpenAIRE

    Okuyama, Kazuki; Ikawa, Tomokatsu; Gentner, Bernhard; Hozumi, Katsuto; Harnprasopwat, Ratanakanit; Lu, Jun; Yamashita, Riu; Ha, Daon; Toyoshima, Takae; Chanda, Bidisha; Kawamata, Toyotaka; Yokoyama, Kazuaki; Wang, Shusheng; Ando, Kiyoshi; Lodish, Harvey F.

    2013-01-01

    Lineage specification is thought to be largely regulated at the level of transcription, where lineage-specific transcription factors drive specific cell fates. MicroRNAs (miR), vital to many cell functions, act posttranscriptionally to decrease the expression of target mRNAs. MLL-AF4 acute lymphocytic leukemia exhibits both myeloid and B-cell surface markers, suggesting that the transformed cells are B-cell myeloid progenitor cells. Through gain- and loss-of-function experiments, we demonstra...

  9. FGFR2IIIb-MAPK Activity Is Required for Epithelial Cell Fate Decision in the Lower Müllerian Duct.

    Science.gov (United States)

    Terakawa, Jumpei; Rocchi, Altea; Serna, Vanida A; Bottinger, Erwin P; Graff, Jonathan M; Kurita, Takeshi

    2016-07-01

    Cell fate of lower Müllerian duct epithelium (MDE), to become uterine or vaginal epithelium, is determined by the absence or presence of ΔNp63 expression, respectively. Previously, we showed that SMAD4 and runt-related transcription factor 1 (RUNX1) were independently required for MDE to express ΔNp63. Here, we report that vaginal mesenchyme directs vaginal epithelial cell fate in MDE through paracrine activation of fibroblast growth factor (FGF) receptor-MAPK pathway. In the developing reproductive tract, FGF7 and FGF10 were enriched in vaginal mesenchyme, whereas FGF receptor 2IIIb was expressed in epithelia of both the uterus and vagina. When Fgfr2 was inactivated, vaginal MDE underwent uterine cell fate, and this differentiation defect was corrected by activation of MEK-ERK pathway. In vitro, FGF10 in combination with bone morphogenetic protein 4 and activin A (ActA) was sufficient to induce ΔNp63 in MDE, and ActA was essential for induction of RUNX1 through SMAD-independent pathways. Accordingly, inhibition of type 1 receptors for activin in neonatal mice induced uterine differentiation in vaginal epithelium by down-regulating RUNX1, whereas conditional deletion of Smad2 and Smad3 had no effect on vaginal epithelial differentiation. In conclusion, vaginal epithelial cell fate in MDE is induced by FGF7/10-MAPK, bone morphogenetic protein 4-SMAD, and ActA-RUNX1 pathway activities, and the disruption in any one of these pathways results in conversion from vaginal to uterine epithelial cell fate. PMID:27164167

  10. Data integration for identification of important transcription factors of STAT6-mediated cell fate decisions.

    Science.gov (United States)

    Jargosch, M; Kröger, S; Gralinska, E; Klotz, U; Fang, Z; Chen, W; Leser, U; Selbig, J; Groth, D; Baumgrass, R

    2016-01-01

    Data integration has become a useful strategy for uncovering new insights into complex biological networks. We studied whether this approach can help to delineate the signal transducer and activator of transcription 6 (STAT6)-mediated transcriptional network driving T helper (Th) 2 cell fate decisions. To this end, we performed an integrative analysis of publicly available RNA-seq data of Stat6-knockout mouse studies together with STAT6 ChIP-seq data and our own gene expression time series data during Th2 cell differentiation. We focused on transcription factors (TFs), cytokines, and cytokine receptors and delineated 59 positively and 41 negatively STAT6-regulated genes, which were used to construct a transcriptional network around STAT6. The network illustrates that important and well-known TFs for Th2 cell differentiation are positively regulated by STAT6 and act either as activators for Th2 cells (e.g., Gata3, Atf3, Satb1, Nfil3, Maf, and Pparg) or as suppressors for other Th cell subpopulations such as Th1 (e.g., Ar), Th17 (e.g., Etv6), or iTreg (e.g., Stat3 and Hif1a) cells. Moreover, our approach reveals 11 TFs (e.g., Atf5, Creb3l2, and Asb2) with unknown functions in Th cell differentiation. This fact together with the observed enrichment of asthma risk genes among those regulated by STAT6 underlines the potential value of the data integration strategy used here. Thus, our results clearly support the opinion that data integration is a useful tool to delineate complex physiological processes. PMID:27420972

  11. Genomic DISC1 Disruption in hiPSCs Alters Wnt Signaling and Neural Cell Fate

    Directory of Open Access Journals (Sweden)

    Priya Srikanth

    2015-09-01

    Full Text Available Genetic and clinical association studies have identified disrupted in schizophrenia 1 (DISC1 as a candidate risk gene for major mental illness. DISC1 is interrupted by a balanced chr(1;11 translocation in a Scottish family in which the translocation predisposes to psychiatric disorders. We investigate the consequences of DISC1 interruption in human neural cells using TALENs or CRISPR-Cas9 to target the DISC1 locus. We show that disruption of DISC1 near the site of the translocation results in decreased DISC1 protein levels because of nonsense-mediated decay of long splice variants. This results in an increased level of canonical Wnt signaling in neural progenitor cells and altered expression of fate markers such as Foxg1 and Tbr2. These gene expression changes are rescued by antagonizing Wnt signaling in a critical developmental window, supporting the hypothesis that DISC1-dependent suppression of basal Wnt signaling influences the distribution of cell types generated during cortical development.

  12. Genomic DISC1 Disruption in hiPSCs Alters Wnt Signaling and Neural Cell Fate.

    Science.gov (United States)

    Srikanth, Priya; Han, Karam; Callahan, Dana G; Makovkina, Eugenia; Muratore, Christina R; Lalli, Matthew A; Zhou, Honglin; Boyd, Justin D; Kosik, Kenneth S; Selkoe, Dennis J; Young-Pearse, Tracy L

    2015-09-01

    Genetic and clinical association studies have identified disrupted in schizophrenia 1 (DISC1) as a candidate risk gene for major mental illness. DISC1 is interrupted by a balanced chr(1;11) translocation in a Scottish family in which the translocation predisposes to psychiatric disorders. We investigate the consequences of DISC1 interruption in human neural cells using TALENs or CRISPR-Cas9 to target the DISC1 locus. We show that disruption of DISC1 near the site of the translocation results in decreased DISC1 protein levels because of nonsense-mediated decay of long splice variants. This results in an increased level of canonical Wnt signaling in neural progenitor cells and altered expression of fate markers such as Foxg1 and Tbr2. These gene expression changes are rescued by antagonizing Wnt signaling in a critical developmental window, supporting the hypothesis that DISC1-dependent suppression of basal Wnt signaling influences the distribution of cell types generated during cortical development. PMID:26299970

  13. Fate of pup inside the Mycobacterium proteasome studied by in-cell NMR.

    Directory of Open Access Journals (Sweden)

    Andres Y Maldonado

    Full Text Available The Mycobacterium tuberculosis proteasome is required for maximum virulence and to resist killing by the host immune system. The prokaryotic ubiquitin-like protein, Pup-GGE, targets proteins for proteasome-mediated degradation. We demonstrate that Pup-GGQ, a precursor of Pup-GGE, is not a substrate for proteasomal degradation. Using STINT-NMR, an in-cell NMR technique, we studied the interactions between Pup-GGQ, mycobacterial proteasomal ATPase, Mpa, and Mtb proteasome core particle (CP inside a living cell at amino acid residue resolution. We showed that under in-cell conditions, in the absence of the proteasome CP, Pup-GGQ interacts with Mpa only weakly, primarily through its C-terminal region. When Mpa and non-stoichiometric amounts of proteasome CP are present, both the N-terminal and C-terminal regions of Pup-GGQ bind strongly to Mpa. This suggests a mechanism by which transient binding of Mpa to the proteasome CP controls the fate of Pup.

  14. Fate and protective effect of marrow stromal cells after subretinal transplantation

    Institute of Scientific and Technical Information of China (English)

    Hong Pan; Xinjian Liu; Jihong Wu; Yuhua Tian; Shenghai Zhang; Zhixin Lin; Qian Huang

    2008-01-01

    Engraftment of marrow stromai cells(MSCs)has been proposed as a therapeutic approach for degenerative diseases.In this study we investigated the fate and dynamic progress of grafted MSCs in living retina with the aim of evaluating the use of transplanted MSCs to treat retinal degeneration.Approximately 1×10 5 gfp-MSCs in 2 μl phosphate-buffered saline were injected into the subretinal space of adult Sprague-Dawley rats.Two weeks later,approximately 0.174%±O.082% of the transplanted cells had survived and diffused into the subretinal space.Nine weeks after transplantation the surviving gfp-MSCs accounted for 0.049%±0.023% of the number of cells injected and were mainly located at the injection site.The same number of MSCs were transplanted into the left eye subretinal space of 3-week-old hereditary retinal degenerative Royal College of Surgeons rats,and phosphate-buffered saline was injected into their right eyes as a control.Five weeks after transplantation,the amount of rudimentary photoreceptors was more significantly increased in grafted eyes than in control eyes.The results indicated that grafted MS CS could survive and rescue retinal degeneration.

  15. Foodomics study on the effects of extracellular production of hydrogen peroxide by rosemary polyphenols on the anti-proliferative activity of rosemary polyphenols against HT-29 cells.

    Science.gov (United States)

    Valdés, Alberto; García-Cañas, Virginia; Koçak, Engin; Simó, Carolina; Cifuentes, Alejandro

    2016-07-01

    A number of studies have demonstrated a strong association between the antioxidant properties of rosemary polyphenols and their chemoprotective activity. However, the prooxidant effects of rosemary polyphenols have been rarely reported. In this work, a foodomics study is performed to investigate the in vitro autooxidation of carnosic acid (CA), carnosol (CS) and a polyphenol-enriched rosemary extract (SC-RE) in cell culture conditions. The results revealed that rosemary polyphenols autooxidation in culture medium generated H2 O2 at different rates. Generated H2 O2 levels by SC-RE and CA, but not CS, were correlated with intracellular reactive oxygen species (ROS) generation in HT-29 cells, and were partially involved in their anti-proliferative effect in this cell line. These compounds also induced different effects on glutathione metabolism. Results also indicated that high extracellular H2 O2 concentrations, resulting of using high (45 μg/mL) SC-RE concentration in culture media, exerted some artifactual effects related with cell cycle, but they did not influence the expression of relevant molecular biomarkers of stress. PMID:26842614

  16. Neuregulin3 alters cell fate in the epidermis and mammary gland

    Directory of Open Access Journals (Sweden)

    Ashworth Alan

    2007-09-01

    Full Text Available Abstract Background The Neuregulin family of ligands and their receptors, the Erbb tyrosine kinases, have important roles in epidermal and mammary gland development as well as during carcinogenesis. Previously, we demonstrated that Neuregulin3 (Nrg3 is a specification signal for mammary placode formation in mice. Nrg3 is a growth factor, which binds and activates Erbb4, a receptor tyrosine kinase that regulates cell proliferation and differentiation. To understand the role of Neuregulin3 in epidermal morphogenesis, we have developed a transgenic mouse model that expresses Nrg3 throughout the basal layer (progenitor/stem cell compartment of mouse epidermis and the outer root sheath of developing hair follicles. Results Transgenic females formed supernumerary nipples and mammary glands along and adjacent to the mammary line providing strong evidence that Nrg3 has a role in the initiation of mammary placodes along the body axis. In addition, alterations in morphogenesis and differentiation of other epidermal appendages were observed, including the hair follicles. The transgenic epidermis is hyperplastic with excessive sebaceous differentiation and shows striking similarities to mouse models in which c-Myc is activated in the basal layer including decreased expression levels of the adhesion receptors, α6-integrin and β1-integrin. Conclusion These results indicate that the epidermis is sensitive to Nrg3 signaling, and that this growth factor can regulate cell fate of pluripotent epidermal cell populations including that of the mammary gland. Nrg3 appears to act, in part, by inducing c-Myc, altering the proliferation and adhesion properties of the basal epidermis, and may promote exit from the stem cell compartment. The results we describe provide significant insight into how growth factors, such as Nrg3, regulate epidermal homeostasis by influencing the balance between stem cell renewal, lineage selection and differentiation.

  17. Telomerase expression extends the proliferative life-span and maintains the osteogenic potential of human bone marrow stromal cells

    DEFF Research Database (Denmark)

    Simonsen, Janne Lytoft; Kjeldsen, Cecilia Rosada; Serakinci, Nedime;

    2002-01-01

    Human bone marrow stromal cells (hMSCs) were stably transduced by a retroviral vector containing the gene for the catalytic subunit of human telomerase (hTERT). Transduced cells (hMSC-TERTs) had telomerase activity, and the mean telomere length was increased as compared with that of control cells...... subculturing, did not form tumors, and had a normal karyotype. When implanted subcutaneously in immunodeficient mice, the transduced cells formed more bone than did normal cells. These results suggest that ectopic expression of telomerase in hMSCs prevents senescence-associated impairment of osteoblast...

  18. Feedback from each retinal neuron population drives expression of subsequent fate determinant genes without influencing the cell cycle exit timing.

    Science.gov (United States)

    Kei, Jeremy Ng Chi; Dudczig, Stefanie; Currie, Peter D; Jusuf, Patricia R

    2016-09-01

    During neurogenesis, progenitors balance proliferation and cell cycle exit together with expression of fate determinant genes to ensure that the correct number of each of these neuron types is generated. Although intrinsic gene expression acting cell autonomously within each progenitor drives these processes, the final number of neurons generated is also influenced by extrinsic cues, representing a potential avenue to direct neurogenesis in developmental disorders or regenerative settings without the requirement to change intrinsic gene expression. Thus, it is important to understand which of these stages of neurogenesis are amenable to such extrinsic influences. Additionally, all types of neurons are specified in a highly conserved histogenic order, although its significance is unknown. This study makes use of conserved patterns of neurogenesis in the relatively simple yet highly organized zebrafish retina model, in which such histogenic birth order is well characterized. We directly visualize and quantify birth dates and cell fate determinant expression in WT vs. environments lacking different neuronal populations. This study shows that extrinsic feedback from developing retinal neurons is important for the temporal expression of intrinsic fate determinants but not for the timing of birth dates. We found no changes in cell cycle exit timing but did find a significant delay in the expression of genes driving the generation only of later- but not earlier-born cells, suggesting that the robustness of this process depends on continuous feedback from earlier-formed cell types. Thus, extrinsic cues selectively influence cell fate determinant progression, which may explain the function of the retinal histogenic order observed. J. Comp. Neurol. 524:2553-2566, 2016. © 2016 Wiley Periodicals, Inc. PMID:26850379

  19. Anti-proliferative effect of biogenic gold nanoparticles against breast cancer cell lines (MDA-MB-231 & MCF-7)

    Science.gov (United States)

    K. S., Uma Suganya; Govindaraju, K.; Ganesh Kumar, V.; Prabhu, D.; Arulvasu, C.; Stalin Dhas, T.; Karthick, V.; Changmai, Niranjan

    2016-05-01

    Breast cancer is a major complication in women and numerous approaches are being developed to overcome this problem. In conventional treatments such as chemotherapy and radiotherapy the post side effects cause an unsuitable effect in treatment of cancer. Hence, it is essential to develop a novel strategy for the treatment of this disease. In the present investigation, a possible route for green synthesis of gold nanoparticles (AuNPs) using leaf extract of Mimosa pudica and its anticancer efficacy in the treatment of breast cancer cell lines is studied. The synthesized nanoparticles were found to be effective in killing cancer cells (MDA-MB-231 & MCF-7) which were studied using various anticancer assays (MTT assay, cell morphology determination, cell cycle analysis, comet assay, Annexin V-FITC/PI staining and DAPI staining). Cell morphological analysis showed the changes occurred in cancer cells during the treatment with AuNPs. Cell cycle analysis revealed apoptosis in G0/G1 to S phase. Similarly in Comet assay, there was an increase in tail length in treated cells in comparison with the control. Annexin V-FITC/PI staining assay showed prompt fluorescence in treated cells indicating the translocation of phosphatidylserine from the inner membrane. PI and DAPI staining showed the DNA damage in treated cells.

  20. Number and proliferative capacity of osteogenic stem cells are maintained during aging and in patients with osteoporosis

    DEFF Research Database (Denmark)

    Dokkedahl, Karin Stenderup; Justesen, J; Eriksen, E F;

    2001-01-01

    [age, 66-74 years]) and 13 patients with osteoporosis (age, 58-83 years). Bone marrow was aspirated from iliac crest; mononuclear cells were enriched in MSCs by magnetic activated cell sorting (MACS) using STRO-1 antibody. Total CFU-F number, size distribution, cell density per CFU-F, number of...... alkaline phosphatase positive (ALP+) CFU-Fs, and the total ALP+ cells were determined. In addition, matrix mineralization as estimated by alizarin red S (AR-S) staining was quantified. No significant difference in colony-forming efficiency between young individuals (mean +/- SEM; 87 +/- 12 CFU...

  1. Exine dehiscing induces rape microspore polarity, which results in different daughter cell fate and fixes the apical–basal axis of the embryo

    Science.gov (United States)

    Tang, Xingchun; Liu, Yuan; Sun, Meng-xiang

    2013-01-01

    The roles of cell polarity and the first asymmetric cell division during early embryogenesis in apical–basal cell fate determination remain unclear. Previously, a novel Brassica napus microspore embryogenesis system was established, by which rape exine-dehisced microspores were induced by physical stress. Unlike traditional microspore culture, cell polarity and subsequent asymmetric division appeared in the exine-dehisced microspore, which finally developed into a typical embryo with a suspensor. Further studies indicated that polarity is critical for apical–basal cell fate determination and suspensor formation. However, the pattern of the first division was not only determined by cell polarity but was also regulated by the position of the ruptured exine. The first division could be equal or unequal, with its orientation essentially perpendicular to the polar axis. In both types of cell division, the two daughter cells could have different cell fates and give rise to an embryo with a suspensor, similar to zygotic apical–basal cell differentiation. The alignment of the two daughter cells is consistent with the orientation of the apical–basal axis of future embryonic development. Thus, the results revealed that exine dehiscing induces rape microspore polarization, and this polarity results in a different cell fate and fixes the apical–basal axis of embryogenesis, but is uncoupled from cell asymmetric division. The present study demonstrated the relationships among cell polarity, asymmetric cell division, and cell fate determination in early embryogenesis. PMID:23162119

  2. Exine dehiscing induces rape microspore polarity, which results in different daughter cell fate and fixes the apical-basal axis of the embryo.

    Science.gov (United States)

    Tang, Xingchun; Liu, Yuan; He, Yuqing; Ma, Ligang; Sun, Meng-Xiang

    2013-01-01

    The roles of cell polarity and the first asymmetric cell division during early embryogenesis in apical-basal cell fate determination remain unclear. Previously, a novel Brassica napus microspore embryogenesis system was established, by which rape exine-dehisced microspores were induced by physical stress. Unlike traditional microspore culture, cell polarity and subsequent asymmetric division appeared in the exine-dehisced microspore, which finally developed into a typical embryo with a suspensor. Further studies indicated that polarity is critical for apical-basal cell fate determination and suspensor formation. However, the pattern of the first division was not only determined by cell polarity but was also regulated by the position of the ruptured exine. The first division could be equal or unequal, with its orientation essentially perpendicular to the polar axis. In both types of cell division, the two daughter cells could have different cell fates and give rise to an embryo with a suspensor, similar to zygotic apical-basal cell differentiation. The alignment of the two daughter cells is consistent with the orientation of the apical-basal axis of future embryonic development. Thus, the results revealed that exine dehiscing induces rape microspore polarization, and this polarity results in a different cell fate and fixes the apical-basal axis of embryogenesis, but is uncoupled from cell asymmetric division. The present study demonstrated the relationships among cell polarity, asymmetric cell division, and cell fate determination in early embryogenesis. PMID:23162119

  3. YUCCA-mediated auxin biogenesis is required for cell fate transition occurring during de novo root organogenesis in Arabidopsis.

    Science.gov (United States)

    Chen, Lyuqin; Tong, Jianhua; Xiao, Langtao; Ruan, Ying; Liu, Jingchun; Zeng, Minhuan; Huang, Hai; Wang, Jia-Wei; Xu, Lin

    2016-07-01

    Many plant organs have the ability to regenerate a new plant after detachment or wounding via de novo organogenesis. During de novo root organogenesis from Arabidopsis thaliana leaf explants, endogenic auxin is essential for the fate transition of regeneration-competent cells to become root founder cells via activation of WUSCHEL-RELATED HOMEOBOX 11 (WOX11). However, the molecular events from leaf explant detachment to auxin-mediated cell fate transition are poorly understood. In this study, we used an assay to determine the concentration of indole-3-acetic acid (IAA) to provide direct evidence that auxin is produced after leaf explant detachment, a process that involves YUCCA (YUC)-mediated auxin biogenesis. Inhibition of YUC prevents expression of WOX11 and fate transition of competent cells, resulting in the blocking of rooting. Further analysis showed that YUC1 and YUC4 act quickly (within 4 hours) in response to wounding after detachment in both light and dark conditions and promote auxin biogenesis in both mesophyll and competent cells, whereas YUC5, YUC8, and YUC9 primarily respond in dark conditions. In addition, YUC2 and YUC6 contribute to rooting by providing a basal auxin level in the leaf. Overall, our study indicates that YUC genes exhibit a division of labour during de novo root organogenesis from leaf explants in response to multiple signals. PMID:27255928

  4. Aurora A Kinase Regulates Mammary Epithelial Cell Fate by Determining Mitotic Spindle Orientation in a Notch-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Joseph L. Regan

    2013-07-01

    Full Text Available Cell fate determination in the progeny of mammary epithelial stem/progenitor cells remains poorly understood. Here, we have examined the role of the mitotic kinase Aurora A (AURKA in regulating the balance between basal and luminal mammary lineages. We find that AURKA is highly expressed in basal stem cells and, to a lesser extent, in luminal progenitors. Wild-type AURKA expression promoted luminal cell fate, but expression of an S155R mutant reduced proliferation, promoted basal fate, and inhibited serial transplantation. The mechanism involved regulation of mitotic spindle orientation by AURKA and the positioning of daughter cells after division. Remarkably, this was NOTCH dependent, as NOTCH inhibitor blocked the effect of wild-type AURKA expression on spindle orientation and instead mimicked the effect of the S155R mutant. These findings directly link AURKA, NOTCH signaling, and mitotic spindle orientation and suggest a mechanism for regulating the balance between luminal and basal lineages in the mammary gland.

  5. Proliferative effect of whey from cow's milk obtained at two different stages of pregnancy measured in MCF-7 cells

    DEFF Research Database (Denmark)

    Nielsen, Tina S; Andersen, Charlotte; Sejrsen, Kristen;

    2012-01-01

    (whey) in a proliferation assay with estrogen-sensitive MCF-7 human breast cancer cells. Milk samples were obtained from 22 cows representing different stages of pregnancy (first and second half) and whey was produced from the milk. 0·1, 0·25 or 0·5% whey was included in the cell culture medium and...

  6. Protein O-mannosylation is crucial for human mesencyhmal stem cells fate.

    Science.gov (United States)

    Ragni, E; Lommel, M; Moro, M; Crosti, M; Lavazza, C; Parazzi, V; Saredi, S; Strahl, S; Lazzari, L

    2016-01-01

    Human mesenchymal stem cells (MSC) are promising cell types in the field of regenerative medicine. Although many pathways have been dissected in the effort to better understand and characterize MSC potential, the impact of protein N- or O-glycosylation has been neglected. Deficient protein O-mannosylation is a pathomechanism underlying severe congenital muscular dystrophies (CMD) that start to develop at the embryonic developmental stage and progress in the adult, often in tissues where MSC exert their function. Here we show that O-mannosylation genes, many of which are putative or verified glycosyltransferases (GTs), are expressed in a similar pattern in MSC from adipose tissue, bone marrow, and umbilical cord blood and that their expression levels are retained constant during mesengenic differentiation. Inhibition of the first players of the enzymatic cascade, POMT1/2, resulted in complete abolishment of chondrogenesis and alterations of adipogenic and osteogenic potential together with a lethal effect during myogenic induction. Since to date, no therapy for CMD is available, we explored the possibility of using MSC extracellular vesicles (EVs) as molecular source of functional GTs mRNA. All MSC secrete POMT1 mRNA-containing EVs that are able to efficiently fuse with myoblasts which are among the most affected cells by CMD. Intriguingly, in a pomt1 patient myoblast line EVs were able to partially revert O-mannosylation deficiency and contribute to a morphology recovery. Altogether, these results emphasize the crucial role of protein O-mannosylation in stem cell fate and properties and open the possibility of using MSC vesicles as a novel therapeutic approach to CMD. PMID:26245304

  7. Human adipose stem cells maintain proliferative, synthetic and multipotential properties when suspension cultured as self-assembling spheroids

    International Nuclear Information System (INIS)

    Adipose-derived stromal/stem cells (ASCs) have been gaining recognition as an extremely versatile cell source for tissue engineering. The usefulness of ASCs in biofabrication is further enhanced by our demonstration of the unique properties of these cells when they are cultured as three-dimensional cellular aggregates or spheroids. As described herein, three-dimensional formulations, or self-assembling ASC spheroids develop their own extracellular matrix that serves to increase the robustness of the cells to mechanical stresses. The composition of the extracellular matrix can be altered based on the external environment of the spheroids and these constructs can be grown in a reproducible manner and to a consistent size. The spheroid formulation helps preserve the viability and developmental plasticity of ASCs even under defined, serum-free media conditions. For the first time, we show that multiple generations of adherent ASCs produced from these spheroids retain their ability to differentiate into multiple cell/tissue types. These demonstrated properties support the idea that culture-expanded ASCs are an excellent candidate cellular material for ‘organ printing’—the approach of developing complex tissue structures from a standardized cell ‘ink’ or cell formulation. (paper)

  8. A monoclonal antibody (8H3) that binds to rat T lineage cells and augments in vitro proliferative responses

    OpenAIRE

    1990-01-01

    A murine monoclonal antibody, designated 8H3, recognizes a cell surface antigen expressed exclusively on rat T lineage cells. 8H3 antibody immunoprecipitated 180-, 120-, and 90-kD components from rat thymocytes as well as splenic T cells under nonreducing conditions. 8H3 antibody specifically inhibited the binding of thymocytes to fibronectin. Furthermore, binding of rat thymocytes to immobilized synthetic peptide Gly-Arg-Gly-Asp-Ser-Pro-Cys-BSA was inhibited by 8H3 antibody as was Gly-Arg-Gl...

  9. Development of transplant vasculopathy in aortic allografts correlates with neointimal smooth muscle cell proliferative capacity and fibrocyte frequency

    NARCIS (Netherlands)

    Onuta, Geanina; van Ark, Joris; Rienstra, Heleen; Boer, Mark Walther; Klatter, Flip A.; Bruggeman, Cathrien A.; Zeebregts, Clark J.; Rozing, Jan; Hillebrands, Jan-Luuk

    2010-01-01

    Objective: Transplant vasculopathy consists of neointima formation in graft vasculature resulting from vascular smooth muscle cell recruitment and proliferation. Variation in the severity of vasculopathy has been demonstrated. Genetic predisposition is suggested as a putative cause of this variation

  10. 18F-FAMT uptake correlates with tumor proliferative activity in oral squamous cell carcinoma. Comparative study with 18F-FDG PET and immunohistochemistry

    International Nuclear Information System (INIS)

    L-3-[18F]-fluoro-α-methyl tyrosine (FAMT) is transported into cancer cells by L-type amino acid transporter 1 (LAT1). The purpose of the present study is to correlate the uptake of FAMT and fluorodeoxyglucose (FDG) with the cellular proliferative activity measured by the Ki-67 labeling index (Ki-67 LI) in oral squamous cell carcinoma (OSCC). Twenty-five patients with OSCC were enrolled in this study. Both FAMT-positron emission tomography (PET) and FDG-PET were performed within 4 weeks before surgery in all cases. The uptake of FAMT and FDG was compared by semiquantitative analysis with maximal standardized uptake values (SUVmax) of the primary tumors. Ki-67 LI of the tumors was analyzed by immunohistochemical staining and correlated with the clinicopathologic variables and the uptake of PET tracers. For primary tumor detection, FAMT-PET exhibited a sensitivity of 84%, whereas that of FDG-PET was 88%. In all visible lesions, mean FDG uptake determined by average SUVmax was 9.7 (range 4.2-15.9) and mean FAMT uptake was 3.5 (range 1.3-8.5). The SUVmax of FAMT tended to show a better correlation with Ki-67 LI (r=0.878) than that of FDG (r=0.643). Uptake of FAMT correlated with cellular proliferation of OSCC. FAMT-PET may be a useful procedure to evaluate tumor proliferation of OSCC. (author)

  11. Neuronal Cell Fate Specification by the Convergence of Different Spatiotemporal Cues on a Common Terminal Selector Cascade.

    Directory of Open Access Journals (Sweden)

    Hugo Gabilondo

    2016-05-01

    Full Text Available Specification of the myriad of unique neuronal subtypes found in the nervous system depends upon spatiotemporal cues and terminal selector gene cascades, often acting in sequential combinatorial codes to determine final cell fate. However, a specific neuronal cell subtype can often be generated in different parts of the nervous system and at different stages, indicating that different spatiotemporal cues can converge on the same terminal selectors to thereby generate a similar cell fate. However, the regulatory mechanisms underlying such convergence are poorly understood. The Nplp1 neuropeptide neurons in the Drosophila ventral nerve cord can be subdivided into the thoracic-ventral Tv1 neurons and the dorsal-medial dAp neurons. The activation of Nplp1 in Tv1 and dAp neurons depends upon the same terminal selector cascade: col>ap/eya>dimm>Nplp1. However, Tv1 and dAp neurons are generated by different neural progenitors (neuroblasts with different spatiotemporal appearance. Here, we find that the same terminal selector cascade is triggered by Kr/pdm>grn in dAp neurons, but by Antp/hth/exd/lbe/cas in Tv1 neurons. Hence, two different spatiotemporal combinations can funnel into a common downstream terminal selector cascade to determine a highly related cell fate.

  12. Neuronal Cell Fate Specification by the Convergence of Different Spatiotemporal Cues on a Common Terminal Selector Cascade.

    Science.gov (United States)

    Gabilondo, Hugo; Stratmann, Johannes; Rubio-Ferrera, Irene; Millán-Crespo, Irene; Contero-García, Patricia; Bahrampour, Shahrzad; Thor, Stefan; Benito-Sipos, Jonathan

    2016-05-01

    Specification of the myriad of unique neuronal subtypes found in the nervous system depends upon spatiotemporal cues and terminal selector gene cascades, often acting in sequential combinatorial codes to determine final cell fate. However, a specific neuronal cell subtype can often be generated in different parts of the nervous system and at different stages, indicating that different spatiotemporal cues can converge on the same terminal selectors to thereby generate a similar cell fate. However, the regulatory mechanisms underlying such convergence are poorly understood. The Nplp1 neuropeptide neurons in the Drosophila ventral nerve cord can be subdivided into the thoracic-ventral Tv1 neurons and the dorsal-medial dAp neurons. The activation of Nplp1 in Tv1 and dAp neurons depends upon the same terminal selector cascade: col>ap/eya>dimm>Nplp1. However, Tv1 and dAp neurons are generated by different neural progenitors (neuroblasts) with different spatiotemporal appearance. Here, we find that the same terminal selector cascade is triggered by Kr/pdm>grn in dAp neurons, but by Antp/hth/exd/lbe/cas in Tv1 neurons. Hence, two different spatiotemporal combinations can funnel into a common downstream terminal selector cascade to determine a highly related cell fate. PMID:27148744

  13. Medium Renewal Blocks Anti-Proliferative Effects of Metformin in Cultured MDA-MB-231 Breast Cancer Cells

    OpenAIRE

    Maruša Rajh; Klemen Dolinar; Katarina Miš; Mojca Pavlin; Sergej Pirkmajer

    2016-01-01

    Epidemiological studies indicate that metformin, a widely used type 2 diabetes drug, might reduce breast cancer risk and mortality in patients with type 2 diabetes. Metformin might protect against breast cancer indirectly by ameliorating systemic glucose homeostasis. Alternatively, it might target breast cancer cells directly. However, experiments using MDA-MB-231 cells, a standard in vitro breast cancer model, produced inconsistent results regarding effectiveness of metformin as a direct ant...

  14. Synthesis of new diarylamides with pyrimidinyl pyridine scaffold and evaluation of their anti-proliferative effect on cancer cell lines.

    Science.gov (United States)

    Abdelazem, Ahmed Z; Al-Sanea, Mohammad M; Park, Hyun-Mee; Lee, So Ha

    2016-02-15

    A new series of diarylamides, having a pyrimidinyl pyridine scaffold, was designed and synthesized. The target compounds were synthesized in three steps. A selected group from the target compounds was tested over a panel of 60 cancer cell lines at a single dose concentration of 10μM, and the most active compound, 5j, was further tested in a five-dose testing mode to determine its IC50 value over the 60 cell lines. In single-dose testing mode, compound 5j showed the highest growth inhibition against the NCI-60 cancer cell lines, while other tested compounds showed a weak to moderate inhibitory activity against a range of different cancer cell lines. In five-dose testing mode, compound 5j showed strong inhibitory activity in micro molar range against many cancer cell lines. Its major activity was against melanoma cancer cell lines. Therefore, compound 5j is a promising hit compound targeting this severe form of cancer. PMID:26786696

  15. [Proliferative vitreoretinopathy: curative treatment].

    Science.gov (United States)

    Chiquet, C; Rouberol, F

    2014-10-01

    Proliferative vitreoretinopathy (PVR), which causes contractile fibrocellular membranes that may prevent retinal reattachment, remains one of the most severe complications of rhegmatogenous retinal detachment (RD), with an incidence of 5-11%, and one of the most frequent causes of surgical failure (50-75%). Its severity is due to the complexity of the surgery required to treat patients, and to its uncertain anatomic and functional prognosis. Curative treatment of PVR includes vitrectomy, sometimes associated with phacoemulsification or scleral buckling; systematic peeling of epiretinal membranes, occasionally retinectomy; and systematic retinopexy by endolaser photocoagulation. The current preferred internal tamponade is silicone oil. Silicone oils of various densities are undergoing comparative studies. PMID:24997865

  16. Proliferative sickle cell retinopathy associated with sickle cell trait and gestational diabetes: case report Retinopatia falciforme proliferativa associada a traço falciforme e diabetes gestacional: relato de caso

    Directory of Open Access Journals (Sweden)

    Jefferson Augusto Santana Ribeiro

    2009-06-01

    Full Text Available Proliferative sickle cell retinopathy is an uncommon complication in individuals with sickle cell trait (AS. However, the risk for proliferative retinopathy development is increased in patients with AS hemoglobinopathy associated with systemic conditions or ocular trauma. A case of a patient with AS hemoglobinopathy who developed proliferative sickle cell retinopathy after the occurrence of gestational diabetes and pregnancy-induced hypertension is reported. Hemoglobin electrophoresis revealed presence of A2 5.0%, S 35.0% and A 53.2%. The present case emphasizes the importance of evaluating systemic comorbidities in patients with sickle cell trait during pregnancy since sickle cell retinopathy can progress rapidly, as well as the importance of regular eye fundus examination in these patients.Retinopatia falciforme proliferativa é uma complicação incomum em indivíduos com traço falciforme, havendo, porém, risco aumentado de desenvolver retinopatia proliferativa em pacientes com hemoglobinopatia AS associada a condições sistêmicas ou trauma ocular. Neste artigo será apresentado um caso de paciente com diabetes gestacional, hipertensão arterial sistêmica associada à gravidez e traço falciforme. Eletroforese de hemoglobinas revelou a presença de A2 5,0%, S 35,0% e A 53,2%. Este caso ressalta a importância da avaliação de comorbidades sistêmicas em pacientes com traço falciforme no período gestacional, uma vez que pode ocorrer rápida progressão da retinopatia falciforme, devendo-se realizar também exames regulares do fundo de olho nestes pacientes.

  17. Molecular analysis of ex-vivo CD133+ GBM cells revealed a common invasive and angiogenic profile but different proliferative signatures among high grade gliomas

    Directory of Open Access Journals (Sweden)

    Garcia Juan L

    2010-08-01

    of samples: those discriminated by tumour location and, the most importantly, the group discriminated by their proliferative potential; Conclusions Primary glioblastomas could be sub-classified according to the properties of their CD133+ cells. The molecular characterization of these potential stem cell populations could be critical to find new therapeutic targets and to develop an effective therapy for these tumours with very dismal prognosis.

  18. Molecular analysis of ex-vivo CD133+ GBM cells revealed a common invasive and angiogenic profile but different proliferative signatures among high grade gliomas

    International Nuclear Information System (INIS)

    and, the most importantly, the group discriminated by their proliferative potential; Primary glioblastomas could be sub-classified according to the properties of their CD133+ cells. The molecular characterization of these potential stem cell populations could be critical to find new therapeutic targets and to develop an effective therapy for these tumours with very dismal prognosis

  19. Role of SCHIZORIZA in asymmetric cell division, cell fate segregation and specification in Arabidopsis root development

    NARCIS (Netherlands)

    Jansweijer, V.M.A.

    2013-01-01

    Multicellular organisms develop their large variety of cell types from just one single cell, the zygote. Both plants and animals use asymmetric cell division to establish a multicellular body plan How different cell and tissue types are determined, how patterns are created and maintained, and which

  20. Development of a new Ca2+/calmodulin antagonist and its anti-proliferative activity against colorectal cancer cells

    International Nuclear Information System (INIS)

    We previously identified a cellular target of a cell cycle inhibitor HBC as Ca2+/calmodulin (Ca2+/CaM) through chemical genetics approach. Using the mechanism-based drug design, we developed a new Ca2+/CaM antagonists based on the structure of HBC. The compound, (4-{3,5-bis-[2-(4-hydroxy-3-methoxy-phenyl)-vinyl]-4,5-dihydro-pyrazol-1-yl }-phenyl)-(4-methyl-piperazin-1-yl)-methanone (referred as HBCP), binds to Ca2+/CaM in vitro and inhibits the proliferation of HCT15 colon cancer cells. HBCP induced sustained phosphorylation of ERK1/2 and subsequently activated p21WAF1 expression in HCT15 cells. Moreover, HBCP reversibly induced the G0/G1 cell cycle arrest in the cells. These data demonstrate that HBCP is a new potent Ca2+/CaM antagonist and can be applied for CaM related therapeutic uses

  1. Modulation of rabbit corneal epithelial cells fate using embryonic stem cell extract

    OpenAIRE

    Zhan, Weijiao; Liu, Zhiping; Liu, Ying; Ke, Qicheng; Ding, Yuanyuan; Lu, Xiaoyan; Wang, Zhichong

    2010-01-01

    Purpose To develop a new culture system to cultivate differentiated autologous cells in vitro for cell therapy and tissue engineering. Methods After incubation in murine embryonic stem cell (ESC) extract for 1 h, streptolysin-O (SLO) permeabilized cells were resealed with CaCl2 and continually cultured for weeks. The morphological study was analyzed by light microscopy. Isolated colonies were selected and expanded to establish cell lines. Octamer-4 (Oct-4), stage-specific embryonic antigen-1 ...

  2. Essential role of Bmp signaling and its positive feedback loop in the early cell fate evolution of chordates

    Czech Academy of Sciences Publication Activity Database

    Kozmiková, Iryna; Candiani, S.; Fabian, Peter; Gurská, Daniela; Kozmik, Zbyněk

    2013-01-01

    Roč. 382, č. 2 (2013), s. 538-554. ISSN 0012-1606 R&D Projects: GA ČR GCP305/10/J064; GA MŠk EE2.3.30.0027 Institutional support: RVO:68378050 Keywords : Bmp signaling * axial patterning * cell fate * chordates * evolution Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.637, year: 2013

  3. Anti-Proliferative Activity of Meroditerpenoids Isolated from the Brown Alga Stypopodium flabelliforme against Several Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Patricia Valentao

    2011-05-01

    Full Text Available The sea constitutes one of the most promising sources of novel compounds with potential application in human therapeutics. In particular, algae have proved to be an interesting source of new bioactive compounds. In this work, six meroditerpenoids (epitaondiol, epitaondiol diacetate, epitaondiol monoacetate, stypotriol triacetate, 14-ketostypodiol diacetate and stypodiol isolated from the brown alga Stypopodium flabelliforme were tested for their cell proliferation inhibitory activity in five cell lines. Cell lines tested included human colon adenocarcinoma (Caco-2, human neuroblastoma (SH-SY5Y, rat basophilic leukemia (RBL-2H3, murine macrophages (RAW.267 and Chinese hamster fibroblasts (V79. Antimicrobial activity of the compounds was also evaluated against Staphylococcus aureus, Salmonella typhimurium, Proteus mirabilis, Bacillus cereus, Enterococcus faecalis and Micrococcus luteus. Overall, the compounds showed good activity against all cell lines, with SH-SY5Y and RAW.267 being the most susceptible. Antimicrobial capacity was observed for epitaondiol monoacetate, stypotriol triacetate and stypodiol, with the first being the most active. The results suggest that these molecules deserve further studies in order to evaluate their potential as therapeutic agents.

  4. Influence of interferon preparations on the proliferative capacity of human and mouse bone marrow cells in vitro

    NARCIS (Netherlands)

    E. van 't Hull (Eveline); B. Löwenberg (Bob); M. de Vries (Marco); H. Schellekens (Huub)

    1978-01-01

    textabstractThe toxicity of interferon to bone marrow was studied by the use of in vitro colony forming assays for hemopoietic cells. In the same study the relative inhibitory effects of two clinically common interferon preparations, leukocyte and fibroblast interferons, were compared with regard to

  5. Anti-proliferative actions of 2-decylamino-5,8-dimethoxy-1,4-naphthoquinone in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jung-Jin [Department of Pharmacology, Chungnam National University College of Pharmacy, Daejeon 305-764 (Korea, Republic of); Institute of Drug Research and Development, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Zhang, Wei-Yun; Yi, Hyoseok; Kim, Yohan; Kim, In-Su [Department of Pharmacology, Chungnam National University College of Pharmacy, Daejeon 305-764 (Korea, Republic of); Shen, Gui-Nan; Song, Gyu-Yong [Department of Medicinal Chemistry, Chungnam National University College of Pharmacy, Daejeon 305-764 (Korea, Republic of); Myung, Chang-Seon, E-mail: cm8r@cnu.ac.kr [Department of Pharmacology, Chungnam National University College of Pharmacy, Daejeon 305-764 (Korea, Republic of); Institute of Drug Research and Development, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2011-07-22

    Highlights: {yields} 2-Decylamino-DMNQ inhibited PDGF-BB-induced VSMC proliferation in a dose-dependent manner with no apparent cytotoxicity. {yields} 2-Decylamino-DMNQ inhibited PDGF-BB-induced phosphorylation of Erk1/2 and PLC{gamma}1. {yields} 2-Decylamino-DMNQ arrested a G{sub 0}/G{sub 1} cell cycle progression in association with pRb phosphorylation and PCNA expression. {yields} Both U0126, an Erk inhibitor, and U73122, a PLC{gamma} inhibitor, arrested a G{sub 0}/G{sub 1} phase of the cell cycle. -- Abstract: Naphthoquinone derivatives have been reported to possess various pharmacological activities, such as antiplatelet, anticancer, antifungal, and antiviral properties. In this study, we investigated the effects of a newly-synthesized naphthoquinone derivative, 2-decylamino-5,8-dimethoxy-1,4-naphthoquinone (2-decylamino-DMNQ), on VSMC proliferation and examined the molecular basis of the underlying mechanism. In a dose-dependent manner, 2-decylamino-DMNQ inhibited PDGF-stimulated VSMC proliferation with no apparent cytotoxic effect. While 2-decylamino-DMNQ did not affect PDGF-R{beta} or Akt, it did inhibit the phosphorylation of Erk1/2 and PLC{gamma}1 induced by PDGF. Moreover, 2-decylamino-DMNQ suppressed DNA synthesis through the arrest of cell cycle progression at the G{sub 0}/G{sub 1} phase, including the suppression of pRb phosphorylation and a decrease in PCNA expression, which was related to the downregulation of cell cycle regulatory factors, such as cyclin D1/E and CDK 2/4. It was demonstrated that both U0126, an Erk1/2 inhibitor, and U73122, a PLC{gamma} inhibitor, increased the proportion of cells in the G{sub 0}/G{sub 1} phase of the cell cycle. Thus, these results suggest that 2-decylamino DMNQ has an inhibitory effect on PDGF-induced VSMC proliferation and the mechanism of this action is through cell cycle arrest at the G{sub 0}/G{sub 1} phase. This may be a useful tool for studying interventions for vascular restenosis in coronary

  6. INSULIN ANALOGUES: ANALYSIS OF PROLIFERATIVE POTENCY AND CHARACTERIZATION OF RECEPTORS AND SIGNALLING PATHWAYS ACTIVATED IN HUMAN MAMMARY EPITHELIAL CELLS

    OpenAIRE

    Shukla, Ashish

    2009-01-01

    Insulin analogues have been developed with the aim to provide better glycaemic control to diabetic patients. They are generated by modifying the insulin backbone which, however, may alter relevant biochemical characteristics such as the affinity to insulin receptor and type I insulin-like growth factor receptor (IGF-IR), and the insulin receptor dissociation rate. As a result insulin analogues may exhibit stronger mitogenic potency than regular insulin. Normal mammary epithelial cells show hi...

  7. Efavirenz Has the Highest Anti-Proliferative Effect of Non-Nucleoside Reverse Transcriptase Inhibitors against Pancreatic Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Markus Hecht

    Full Text Available Cancer prevention and therapy in HIV-1-infected patients will play an important role in future. The non-nucleoside reverse transcriptase inhibitors (NNRTI Efavirenz and Nevirapine are cytotoxic against cancer cells in vitro. As other NNRTIs have not been studied so far, all clinically used NNRTIs were tested and the in vitro toxic concentrations were compared to drug levels in patients to predict possible anti-cancer effects in vivo.Cytotoxicity was studied by Annexin-V-APC/7AAD staining and flow cytometry in the pancreatic cancer cell lines BxPC-3 and Panc-1 and confirmed by colony formation assays. The 50% effective cytotoxic concentrations (EC50 were calculated and compared to the blood levels in our patients and published data.The in vitro EC50 of the different drugs in the BxPC-3 pancreatic cancer cells were: Efavirenz 31.5 μmol/l (= 9944 ng/ml, Nevirapine 239 μmol/l (= 63,786 ng/ml, Etravirine 89.0 μmol/l (= 38,740 ng/ml, Lersivirine 543 μmol/l (= 168,523 ng/ml, Delavirdine 171 μmol/l (= 78,072 ng/ml, Rilpivirine 24.4 μmol/l (= 8941 ng/ml. As Efavirenz and Rilpivirine had the highest cytotoxic potential and Nevirapine is frequently used in HIV-1 positive patients, the results of these three drugs were further studied in Panc-1 pancreatic cancer cells and confirmed with colony formation assays. 205 patient blood levels of Efavirenz, 127 of Rilpivirine and 31 of Nevirapine were analyzed. The mean blood level of Efavirenz was 3587 ng/ml (range 162-15,363 ng/ml, of Rilpivirine 144 ng/ml (range 0-572 ng/ml and of Nevirapine 4955 ng/ml (range 1856-8697 ng/ml. Blood levels from our patients and from published data had comparable Efavirenz levels to the in vitro toxic EC50 in about 1 to 5% of all patients.All studied NNRTIs were toxic against cancer cells. A low percentage of patients taking Efavirenz reached in vitro cytotoxic blood levels. It can be speculated that in HIV-1 positive patients having high Efavirenz blood levels pancreatic

  8. 59. Protectivc effect of melatonin on genetic damage by chemical mutagen and the influence on cell prolife-ration kenetics

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: In this study, we observed the effect of melatonin on the frequency of sister chromatid exchange, micronucleus formation of binuclear cell in lymphocyte from human peripheral blood in vitro, micronucleus formation of mouse bone marrow polycychromatic erythrocyte in vivo, which were induced by chemical mutagen, and lymphocyte proliferation kenetics in vitro. Methods: ① Lymphocytes were cultured in vitro in the presence of 0.01,0.10,1.00 mmol/L melatonin, mitomycin C(MMC) (positive control), 0.5% ethanol (negative control)and 0.01,0.10,1.00 mmol/L melatonin plus MMC for 72 h at 37℃±1℃. Lymphocytes were examined for the frequence of SCE, mitotic index, cell proliferation cycle, cell cycle ratio and proliferation index. ② Lymphocytes were cultured in vitro in the presence of 0.01,0.10,1.00 mmol/L melatonin, mitomycin C(MMC) (positive control), 0.5% ethanol (negative control) and 0.01,0.10,1.00 mmol/L melatonin plus MMC for 44 h at 37℃±1℃. Then each culture was given cytochalasin B, which was cultured to 72 h. Binuclear lymphocytes were examined for the micronucleus rate. ③ The mice were administered with 0.1, 1.0,10.0 mg/kg*bw melatonin and distillated water (negative control) respectively for 7 d, then were given melatonin plus cyclophosphamide (CP) (positive control) for 2 d since the eighth day. The rate of micronulclei of mouse bone marrow polycychromatic erythrocyte was examined. Results: ① The frequences of sister chromatid exchange of lymphocytes which were cultured in the presence of 0.01,0.10,1.00 mmol/L melatonin compared with negative control exhibited no statistical significance. ② The SCE of cells treated with melatonin plus MMC compared with positive control were markedly decreased. ③ The mitotic indices of lymphocytes cultured in the presence of 0.10,1.00 mmol/L melatonin were lower than negative control. The proliferation index was significant lower than negative control only in the culture exposed to 1.00 mmol

  9. Combination of low O(2) concentration and mesenchymal stromal cells during culture of cord blood CD34(+) cells improves the maintenance and proliferative capacity of hematopoietic stem cells.

    Science.gov (United States)

    Hammoud, Mohammad; Vlaski, Marija; Duchez, Pascale; Chevaleyre, Jean; Lafarge, Xavier; Boiron, Jean-Michel; Praloran, Vincent; Brunet De La Grange, Philippe; Ivanovic, Zoran

    2012-06-01

    The physiological approach suggests that an environment associating the mesenchymal stromal cells (MSC) and low O(2) concentration would be most favorable for the maintenance of hematopoietic stem cells (HSCs) in course of ex vivo expansion of hematopoietic grafts. To test this hypothesis, we performed a co-culture of cord blood CD34(+) cells with or without MSC in presence of cytokines for 10 days at 20%, 5%, and 1.5% O(2) and assessed the impact on total cells, CD34(+) cells, committed progenitors (colony-forming cells-CFC) and stem cells activity (pre-CFC and Scid repopulating cells-SRC). Not surprisingly, the expansion of total cells, CD34(+) cells, and CFC was higher in co-culture and at 20% O(2) compared to simple culture and low O(2) concentrations, respectively. However, co-culture at low O(2) concentrations provided CD34(+) cell and CFC amplification similar to classical culture at 20% O(2) . Interestingly, low O(2) concentrations ensured a better pre-CFC and SRC preservation/expansion in co-culture. Indeed, SRC activity in co-culture at 1.5% O(2) was higher than in freshly isolated CD34(+) cells. Interleukin-6 production by MSC at physiologically low O(2) concentrations might be one of the factors mediating this effect. Our data demonstrate that association of co-culture and low O(2) concentration not only induces sufficient expansion of committed progenitors (with respect to the classical culture), but also ensures a better maintenance/expansion of hematopoietic stem cells (HSCs), pointing to the oxygenation as a physiological regulatory factor but also as a cell engineering tool. PMID:21913190

  10. Apoptosis mediated anti-proliferative effect of compound isolated from Cassia auriculata leaves against human colon cancer cell line

    Science.gov (United States)

    Esakkirajan, M.; Prabhu, N. M.; Manikandan, R.; Beulaja, M.; Prabhu, D.; Govindaraju, K.; Thiagarajan, R.; Arulvasu, C.; Dhanasekaran, G.; Dinesh, D.; Babu, G.

    2014-06-01

    A compound was isolated from Cassia auriculata leaves and characterized by high-performance liquid chromatography (HPLC), liquid chromatography mass spectrometry (LC-MS), UV-vis spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). The in vitro anticancer effect of the compound isolated from C. auriculata was evaluated in human colon cancer cells HCT 15 by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cytotoxicity, nuclear morphology analysis and measurement of lactate dehydrogenase. The isolated compound 4-(2,5 dichlorobenzyl)-2,3,4,5,6,7 hexahydro7(4 methoxyphenyl)benzo[h][1,4,7] triazecin8(1H)-one showed 50% inhibition of HCT 15 cells when tested at 20 μg/ml after 24 h incubation. Cytotoxicity, nuclear morphology and lactate dehydrogenase assays clearly show potent anticancer activity of the isolated compound against colon cancer. Thus, the in vitro findings suggest that the compound isolated from C. auriculata leaves have potent anti-cancer properties with possible clinical applications.

  11. Modulation of rabbit corneal epithelial cells fate using embryonic stem cell extract

    Science.gov (United States)

    Zhan, Weijiao; Liu, Zhiping; Liu, Ying; Ke, Qicheng; Ding, Yuanyuan; Lu, Xiaoyan

    2010-01-01

    Purpose To develop a new culture system to cultivate differentiated autologous cells in vitro for cell therapy and tissue engineering. Methods After incubation in murine embryonic stem cell (ESC) extract for 1 h, streptolysin-O (SLO) permeabilized cells were resealed with CaCl2 and continually cultured for weeks. The morphological study was analyzed by light microscopy. Isolated colonies were selected and expanded to establish cell lines. Octamer-4 (Oct-4), stage-specific embryonic antigen-1 (SSEA-1), transformation-related protein 63 (p63), ATP-binding cassette subfamily G, member 2 (ABCG2), and cytokeratin3 (K3) were detected by indirect immunofluorescent staining. Oct-4, K3, and p63 were also detected by RT–PCR analysis. To examine the stemness characteristics of the induced cells, both alkaline phosphatase (AKP) staining and tumorigenicity detection were performed, respectively. Results Reprogramming was induced in corneal epithelial cells. The reprogrammed cells showed characteristics similar to ESCs in the early weeks, including colony formation, positive AKP staining, and multi-potential differentiation in vivo. Oct-4 and SSEA1 protein expression was upregulated. However, these changes were not persistent or stable. With the passage of time, the colonies became flat. The ESC markers were downregulated, while epithelial cell related proteins gradually increased. Conclusions Less terminal differentiated rabbit corneal epithelial cells could be induced to a more pluripotent state with embryonic stem cell extract (ESC-E). These cells have the potential to return to the beginning of their own lineage and obtain the ability of long-term growth. Our findings indicate that this culture system can generate low-immunogenic autologous cells for use in regenerative medicine. PMID:20664691

  12. Planar cell polarity effector gene Intu regulates cell fate-specific differentiation of keratinocytes through the primary cilia.

    Science.gov (United States)

    Dai, D; Li, L; Huebner, A; Zeng, H; Guevara, E; Claypool, D J; Liu, A; Chen, J

    2013-01-01

    Genes involved in the planar cell polarity (PCP) signaling pathway are essential for a number of developmental processes in mammals, such as convergent extension and ciliogenesis. Tissue-specific PCP effector genes of the PCP signaling pathway are believed to mediate PCP signals in a tissue- and cell type-specific manner. However, how PCP signaling controls the morphogenesis of mammalian tissues remains unclear. In this study, we investigated the role of inturned (Intu), a tissue-specific PCP effector gene, during hair follicle formation in mice. Tissue-specific disruption of Intu in embryonic epidermis resulted in hair follicle morphogenesis arrest because of the failure of follicular keratinocyte to differentiate. Targeting Intu in the epidermis resulted in almost complete loss of primary cilia in epidermal and follicular keratinocytes, and a suppressed hedgehog signaling pathway. Surprisingly, the epidermal stratification and differentiation programs and barrier function were not affected. These results demonstrate that tissue-specific PCP effector genes of the PCP signaling pathway control the differentiation of keratinocytes through the primary cilia in a cell fate- and context-dependent manner, which may be critical in orchestrating the propagation and interpretation of polarity signals established by the core PCP components. PMID:22935613

  13. ShaPINg cell fate upon DNA damage:role of Pin1 isomerase in DNA damage-induced cell death and repair

    Directory of Open Access Journals (Sweden)

    Thomas G Hofmann

    2014-06-01

    Full Text Available The peptidyl-prolyl cis/trans isomerase Pin1 acts as a molecular timer in proline-directed Ser/Thr kinase signaling and shapes cellular responses based on recognition of phosphorylation marks and implementing conformational changes in its substrates. Accordingly, Pin1 has been linked to numerous phosphorylation-controlled signaling pathways and cellular processes such as cell cycle progression, proliferation and differentiation. In addition, Pin1 plays a pivotal role in DNA damage-triggered cell fate decisions. Whereas moderate DNA damage is balanced by DNA repair, cells confronted with massive genotoxic stress are eliminated by the induction of programmed cell death or cellular senescence. In this review we summarize and discuss the current knowledge on how Pin1 specifies cell fate through regulating key players of the apoptotic and the repair branch of the DNA damage response.

  14. Sequence of neuron origin and neocortical laminar fate: relation to cell cycle of origin in the developing murine cerebral wall

    Science.gov (United States)

    Takahashi, T.; Goto, T.; Miyama, S.; Nowakowski, R. S.; Caviness, V. S. Jr

    1999-01-01

    Neurons destined for each region of the neocortex are known to arise approximately in an "inside-to-outside" sequence from a pseudostratified ventricular epithelium (PVE). This sequence is initiated rostrolaterally and propagates caudomedially. Moreover, independently of location in the PVE, the neuronogenetic sequence in mouse is divisible into 11 cell cycles that occur over a 6 d period. Here we use a novel "birth hour" method that identifies small cohorts of neurons born during a single 2 hr period, i.e., 10-20% of a single cell cycle, which corresponds to approximately 1.5% of the 6 d neuronogenetic period. This method shows that neurons arising with the same cycle of the 11 cycle sequence in mouse have common laminar fates even if they arise from widely separated positions on the PVE (neurons of fields 1 and 40) and therefore arise at different embryonic times. Even at this high level of temporal resolution, simultaneously arising cells occupy more than one cortical layer, and there is substantial overlap in the distributions of cells arising with successive cycles. We demonstrate additionally that the laminar representation of cells arising with a given cycle is little if at all modified over the early postnatal interval of histogenetic cell death. We infer from these findings that cell cycle is a neuronogenetic counting mechanism and that this counting mechanism is integral to subsequent processes that determine cortical laminar fate.

  15. miRNA-mediated feedback inhibition of JAK/STAT morphogen signalling establishes a cell fate threshold.

    Science.gov (United States)

    Yoon, Wan Hee; Meinhardt, Hans; Montell, Denise J

    2011-09-01

    Patterns of cell fates generated by morphogens are critically important for normal development; however, the mechanisms by which graded morphogen signals are converted into all-or-none cell fate responses are incompletely understood. In the Drosophila ovary, high and sustained levels of the secreted morphogen Unpaired (Upd) specify the migratory border-cell population by activating the signal transducer and activator of transcription (STAT). A lower or transient level of STAT activity specifies a non-migratory population of follicle cells. Here we identify miR-279 as a component of a feedback pathway that further dampens the response in cells with low levels of JAK/STAT activity. miR-279 directly repressed STAT, and loss of miR-279 mimicked STAT gain-of-function or loss of Apontic (Apt), a known feedback inhibitor of STAT. Apt was essential for miR-279 expression in non-migratory follicle cells, whereas another STAT target, Ken and Barbie (Ken), downregulated miR-279 in border cells. Mathematical modelling and simulations of this regulatory circuit including miR-279, Apt and Ken supported key roles for miR-279 and Apt in generating threshold responses to the Upd gradient. PMID:21857668

  16. Adrenomedullin as a Growth and Cell Fate Regulatory Factor for Adult Neural Stem Cells

    OpenAIRE

    Sonia Martínez-Herrero; Ignacio M Larráyoz; Laura Ochoa-Callejero; Josune García-Sanmartín; Alfredo Martínez

    2012-01-01

    The use of stem cells as a strategy for tissue repair and regeneration is one of the biomedical research areas that has attracted more interest in the past few years. Despite the classic belief that the central nervous system (CNS) was immutable, now it is well known that cell turnover occurs in the mature CNS. Postnatal neurogenesis is subjected to tight regulation by many growth factors, cell signals, and transcription factors. An emerging molecule involved in this process is adrenomedullin...

  17. New naphthalene derivatives and isoquinoline alkaloids from Ancistrocladus cochinchinensis with their anti-proliferative activity on human cancer cells.

    Science.gov (United States)

    Lien, Le Quynh; Linh, Tran My; Giang, Vu Huong; Mai, Nguyen Chi; Nhiem, Nguyen Xuan; Tai, Bui Huu; Cuc, Nguyen Thi; Anh, Hoang Le Tuan; Ban, Ninh Khac; Minh, Chau Van; Kiem, Phan Van

    2016-08-15

    Five new compounds, named ancistronaphtosides A and B (1 and 2), anciscochine (3), anciscochine 6-O-β-d-glucopyranoside (4), and 4'-methoxy-5-epi-ancistecrorine A1 (5), together with tortoside A (6) and 4-hydroxy-2-methoxyphenyl-6-O-syringoyl-β-d-glucopyranoside (7) were isolated from the methanolic extract of Ancistrocladus cochinchinensis. Their chemical structures were established using HR-ESI-MS, NMR spectroscopic, and chiroptical methods. Compound 5 significantly exhibited anti-proliferation against HL-60, LU-1, and SK-MEL-2 cells with IC50 values of 5.0±1.2, 6.5±1.6, and 6.8±2.0μg/mL, respectively. PMID:27423477

  18. An APC:WNT counter-current-like mechanism regulates cell division along the colonic crypt axis: a mechanism that explains how APC mutations induce proliferative abnormalities that drive colon cancer development.

    Directory of Open Access Journals (Sweden)

    Bruce M Boman

    2013-11-01

    Full Text Available APC normally down-regulates WNT signaling in human colon, and APC mutations cause proliferative abnormalities in premalignant crypts leading to colon cancer, but the mechanisms are unclear at the level of spatial and functional organization of the crypt. Accordingly, we postulated a counter-current-like mechanism based on gradients of factors (APC;WNT that regulate colonocyte proliferation along the crypt axis. During crypt renewal, stem cells (SCs at the crypt bottom generate non-SC daughter cells that proliferate and differentiate while migrating upwards. The APC concentration is low at the crypt bottom and high at the top (where differentiated cells reside. WNT signaling, in contrast, is high at the bottom (where SCs reside and low at the top. Given that WNT and APC gradients are counter to one another, we hypothesized that a counter-current-like mechanism exists. Since both APC and WNT signaling components (e.g. survivin are required for mitosis, this mechanism establishes a zone in the lower crypt where conditions are optimal for maximal cell division and mitosis orientation (symmetric versus asymmetric. APC haploinsufficiency diminishes the APC gradient, shifts the proliferative zone upwards, and increases symmetric division, which causes SC overpopulation. In homozygote mutant crypts, these changes are exacerbated. Thus, APC-mutation-induced changes in the counter-current-like mechanism cause expansion of proliferative populations (SCs, rapidly-proliferating cells during tumorigenesis. We propose this mechanism also drives crypt fission, functions in the crypt cycle, and underlies adenoma development. Novel chemoprevention approaches designed to normalize the two gradients and readjust the proliferative zone downwards, might thwart progression of these premalignant changes.

  19. Cytoplasmic NOTCH and membrane-derived β-catenin link cell fate choice to epithelial-mesenchymal transition during myogenesis

    Science.gov (United States)

    Sieiro, Daniel; Rios, Anne C; Hirst, Claire E; Marcelle, Christophe

    2016-01-01

    How cells in the embryo coordinate epithelial plasticity with cell fate decision in a fast changing cellular environment is largely unknown. In chick embryos, skeletal muscle formation is initiated by migrating Delta1-expressing neural crest cells that trigger NOTCH signaling and myogenesis in selected epithelial somite progenitor cells, which rapidly translocate into the nascent muscle to differentiate. Here, we uncovered at the heart of this response a signaling module encompassing NOTCH, GSK-3β, SNAI1 and β-catenin. Independent of its transcriptional function, NOTCH profoundly inhibits GSK-3β activity. As a result SNAI1 is stabilized, triggering an epithelial to mesenchymal transition. This allows the recruitment of β-catenin from the membrane, which acts as a transcriptional co-factor to activate myogenesis, independently of WNT ligand. Our results intimately associate the initiation of myogenesis to a change in cell adhesion and may reveal a general principle for coupling cell fate changes to EMT in many developmental and pathological processes. DOI: http://dx.doi.org/10.7554/eLife.14847.001 PMID:27218451

  20. Hippo pathway effectors control cardiac progenitor cell fate by acting as dynamic sensors of substrate mechanics and nanostructure

    KAUST Repository

    Mosqueira, Diogo

    2014-03-25

    Stem cell responsiveness to extracellular matrix (ECM) composition and mechanical cues has been the subject of a number of investigations so far, yet the molecular mechanisms underlying stem cell mechano-biology still need full clarification. Here we demonstrate that the paralog proteins YAP and TAZ exert a crucial role in adult cardiac progenitor cell mechano-sensing and fate decision. Cardiac progenitors respond to dynamic modifications in substrate rigidity and nanopattern by promptly changing YAP/TAZ intracellular localization. We identify a novel activity of YAP and TAZ in the regulation of tubulogenesis in 3D environments and highlight a role for YAP/TAZ in cardiac progenitor proliferation and differentiation. Furthermore, we show that YAP/TAZ expression is triggered in the heart cells located at the infarct border zone. Our results suggest a fundamental role for the YAP/TAZ axis in the response of resident progenitor cells to the modifications in microenvironment nanostructure and mechanics, thereby contributing to the maintenance of myocardial homeostasis in the adult heart. These proteins are indicated as potential targets to control cardiac progenitor cell fate by materials design. © 2014 American Chemical Society.

  1. Epigenetic profiles signify cell fate plasticity in unipotent spermatogonial stem and progenitor cells

    Science.gov (United States)

    Liu, Ying; Giannopoulou, Eugenia G.; Wen, Duancheng; Falciatori, Ilaria; Elemento, Olivier; Allis, C. David; Rafii, Shahin; Seandel, Marco

    2016-01-01

    Spermatogonial stem and progenitor cells (SSCs) generate adult male gametes. During in vitro expansion, these unipotent murine cells spontaneously convert to multipotent adult spermatogonial-derived stem cells (MASCs). Here we investigate this conversion process through integrative transcriptomic and epigenomic analyses. We find in SSCs that promoters essential to maintenance and differentiation of embryonic stem cells (ESCs) are enriched with histone H3-lysine4 and -lysine 27 trimethylations. These bivalent modifications are maintained at most somatic promoters after conversion, bestowing MASCs an ESC-like promoter chromatin. At enhancers, the core pluripotency circuitry is activated partially in SSCs and completely in MASCs, concomitant with loss of germ cell-specific gene expression and initiation of embryonic-like programs. Furthermore, SSCs in vitro maintain the epigenomic characteristics of germ cells in vivo. Our observations suggest that SSCs encode innate plasticity through the epigenome and that both conversion of promoter chromatin states and activation of cell type-specific enhancers are prominent features of reprogramming. PMID:27117588

  2. Asymmetric cell division and its role in cell fate determination in the green alga Tetraselmis indica

    Indian Academy of Sciences (India)

    Mani Arora; Arga Chandrashekar Anil; Karl Burgess; Jane Delany; Ehsan Mesbahi

    2015-12-01

    The prasinophytes (early diverging Chlorophyta), consisting of simple unicellular green algae, occupy a critical position at the base of the green algal tree of life, with some of its representatives viewed as the cell form most similar to the first green alga, the `ancestral green flagellate'. Relatively large-celled unicellular eukaryotic phytoflagellates (such as Tetraselmis and Scherffelia), traditionally placed in Prasinophyceae but now considered as members of Chlorodendrophyceae (core Chlorophyta), have retained some primitive characteristics of prasinophytes. These organisms share several ultrastructural features with the other core chlorophytes (Trebouxiophyceae, Ulvophyceae and Chlorophyceae). However, the role of Chlorodendrophycean algae as the evolutionary link between cellular individuality and cellular cooperation has been largely unstudied. Here, we show that clonal populations of a unicellular chlorophyte, Tetraselmis indica, consist of morphologically and ultrastructurally variant cells which arise through asymmetric cell division. These cells also differ in their physiological properties. The structural and physiological differences in the clonal cell population correlate to a certain extent with the longevity and function of cells.

  3. Asymmetric cell division and its role in cell fate determination in the green alga Tetraselmis indica

    Digital Repository Service at National Institute of Oceanography (India)

    Arora, M.; Anil, A.C.; Burgess, K.; Delany, J.E.; Mesbahi, E.

    The prasinophytes (early diverging Chlorophyta), consisting of simple unicellular green algae, occupy a critical position at the base of the green algal tree of life, with some of its representatives viewed as the cell form most similar to the first...

  4. The transcription factor GATA3 controls cell fate and maintenance of type 2 innate lymphoid cells

    OpenAIRE

    Hoyler, Thomas; Klose, Christoph S.N.; Souabni, Abdallah; Turqueti-Neves, Adriana; Pfeifer, Dietmar; Rawlins, Emma L.; Voehringer, David; Busslinger, Meinrad; Diefenbach, Andreas

    2012-01-01

    Innate lymphoid cells (ILCs) reside at mucosal surfaces and control immunity to intestinal infections. Type 2 innate lymphoid cells (ILC2) produce cytokines such as IL-5 and IL-13 and are required for immune defense against helminth infections and are involved in the pathogenesis of airway hyperreactivity. Here, we have investigated the role of the transcription factor GATA3 for ILC2 differentiation and maintenance. We showed that ILC2 and their lineage-specified bone marrow precursor (ILC2P)...

  5. A cell cycle kinase with tandem sensory PAS domains integrates cell fate cues

    Science.gov (United States)

    Mann, Thomas H.; Seth Childers, W.; Blair, Jimmy A.; Eckart, Michael R.; Shapiro, Lucy

    2016-01-01

    All cells must integrate sensory information to coordinate developmental events in space and time. The bacterium Caulobacter crescentus uses two-component phospho-signalling to regulate spatially distinct cell cycle events through the master regulator CtrA. Here, we report that CckA, the histidine kinase upstream of CtrA, employs a tandem-PAS domain sensor to integrate two distinct spatiotemporal signals. Using CckA reconstituted on liposomes, we show that one PAS domain modulates kinase activity in a CckA density-dependent manner, mimicking the stimulation of CckA kinase activity that occurs on its transition from diffuse to densely packed at the cell poles. The second PAS domain interacts with the asymmetrically partitioned second messenger cyclic-di-GMP, inhibiting kinase activity while stimulating phosphatase activity, consistent with the selective inactivation of CtrA in the incipient stalked cell compartment. The integration of these spatially and temporally regulated signalling events within a single signalling receptor enables robust orchestration of cell-type-specific gene regulation. PMID:27117914

  6. A cell cycle kinase with tandem sensory PAS domains integrates cell fate cues.

    Science.gov (United States)

    Mann, Thomas H; Seth Childers, W; Blair, Jimmy A; Eckart, Michael R; Shapiro, Lucy

    2016-01-01

    All cells must integrate sensory information to coordinate developmental events in space and time. The bacterium Caulobacter crescentus uses two-component phospho-signalling to regulate spatially distinct cell cycle events through the master regulator CtrA. Here, we report that CckA, the histidine kinase upstream of CtrA, employs a tandem-PAS domain sensor to integrate two distinct spatiotemporal signals. Using CckA reconstituted on liposomes, we show that one PAS domain modulates kinase activity in a CckA density-dependent manner, mimicking the stimulation of CckA kinase activity that occurs on its transition from diffuse to densely packed at the cell poles. The second PAS domain interacts with the asymmetrically partitioned second messenger cyclic-di-GMP, inhibiting kinase activity while stimulating phosphatase activity, consistent with the selective inactivation of CtrA in the incipient stalked cell compartment. The integration of these spatially and temporally regulated signalling events within a single signalling receptor enables robust orchestration of cell-type-specific gene regulation. PMID:27117914

  7. The anti-proliferative effect of L-carnosine correlates with a decreased expression of hypoxia inducible factor 1 alpha in human colon cancer cells.

    Directory of Open Access Journals (Sweden)

    Barbara Iovine

    Full Text Available In recent years considerable attention has been given to the use of natural substances as anticancer drugs. The natural antioxidant dipeptide L-carnosine belongs to this class of molecules because it has been proved to have a significant anticancer activity both in vitro and in vivo. Previous studies have shown that L-carnosine inhibits the proliferation of human colorectal carcinoma cells by affecting the ATP and Reactive Oxygen Species (ROS production. In the present study we identified the Hypoxia-Inducible Factor 1α (HIF-1α as a possible target of L-carnosine in HCT-116 cell line. HIF-1α protein is over-expressed in multiple types of human cancer and is the major cause of resistance to drugs and radiation in solid tumours. Of particular interest are experimental data supporting the concept that generation of ROS provides a redox signal for HIF-1α induction, and it is known that some antioxidants are able to suppress tumorigenesis by inhibiting HIF-1α. In the current study we found that L-carnosine reduces the HIF-1α protein level affecting its stability and decreases the HIF-1 transcriptional activity. In addition, we demonstrated that L-carnosine is involved in ubiquitin-proteasome system promoting HIF-1α degradation. Finally, we compared the antioxidant activity of L-carnosine with that of two synthetic anti-oxidant bis-diaminotriazoles (namely 1 and 2, respectively. Despite these three compounds have the same ability in reducing intracellular ROS, 1 and 2 are more potent scavengers and have no effect on HIF-1α expression and cancer cell proliferation. These findings suggest that an analysis of L-carnosine antioxidant pathway will clarify the mechanism underlying the anti-proliferative effects of this dipeptide on colon cancer cells. However, although the molecular mechanism by which L-carnosine down regulates or inhibits the HIF-1α activity has not been yet elucidated, this ability may be promising in treating hypoxia

  8. The anti-proliferative effect of L-carnosine correlates with a decreased expression of hypoxia inducible factor 1 alpha in human colon cancer cells.

    Science.gov (United States)

    Iovine, Barbara; Oliviero, Giorgia; Garofalo, Mariangela; Orefice, Maria; Nocella, Francesca; Borbone, Nicola; Piccialli, Vincenzo; Centore, Roberto; Mazzone, Massimiliano; Piccialli, Gennaro; Bevilacqua, Maria Assunta

    2014-01-01

    In recent years considerable attention has been given to the use of natural substances as anticancer drugs. The natural antioxidant dipeptide L-carnosine belongs to this class of molecules because it has been proved to have a significant anticancer activity both in vitro and in vivo. Previous studies have shown that L-carnosine inhibits the proliferation of human colorectal carcinoma cells by affecting the ATP and Reactive Oxygen Species (ROS) production. In the present study we identified the Hypoxia-Inducible Factor 1α (HIF-1α) as a possible target of L-carnosine in HCT-116 cell line. HIF-1α protein is over-expressed in multiple types of human cancer and is the major cause of resistance to drugs and radiation in solid tumours. Of particular interest are experimental data supporting the concept that generation of ROS provides a redox signal for HIF-1α induction, and it is known that some antioxidants are able to suppress tumorigenesis by inhibiting HIF-1α. In the current study we found that L-carnosine reduces the HIF-1α protein level affecting its stability and decreases the HIF-1 transcriptional activity. In addition, we demonstrated that L-carnosine is involved in ubiquitin-proteasome system promoting HIF-1α degradation. Finally, we compared the antioxidant activity of L-carnosine with that of two synthetic anti-oxidant bis-diaminotriazoles (namely 1 and 2, respectively). Despite these three compounds have the same ability in reducing intracellular ROS, 1 and 2 are more potent scavengers and have no effect on HIF-1α expression and cancer cell proliferation. These findings suggest that an analysis of L-carnosine antioxidant pathway will clarify the mechanism underlying the anti-proliferative effects of this dipeptide on colon cancer cells. However, although the molecular mechanism by which L-carnosine down regulates or inhibits the HIF-1α activity has not been yet elucidated, this ability may be promising in treating hypoxia-related diseases. PMID

  9. Tracking the fate of her4 expressing cells in the regenerating retina using her4:Kaede zebrafish.

    Science.gov (United States)

    Wilson, Stephen G; Wen, Wen; Pillai-Kastoori, Lakshmi; Morris, Ann C

    2016-04-01

    The Basic-Helix-Loop-Helix-Orange (bHLH-O) transcription factor Hairy-related 4 (her4) is a downstream effector of Notch-Delta signaling that represses expression of typically pro-neural genes in proliferative domains of the central nervous system. Notch-Delta signaling in the retina has been shown to increase in response to injury and influences neuroprotective properties of Müller glia. In contrast to mammals, teleost fish are able to regenerate retinal neurons in response to injury. In zebrafish, her4 is upregulated in the regenerating neural retina in response to both acute and chronic photoreceptor damage, but the contribution of her4 expressing cells to neurogenesis following acute or chronic retinal damage has remained unexplored. Here we investigate the role of her4 in the regenerating retina in a background of chronic, rod-specific degeneration as well as following acute light damage. We demonstrate that her4 is expressed in the persistently neurogenic ciliary marginal zone (CMZ), as well as in small subsets of slowly proliferating Müller glia in the inner nuclear layer (INL) of the central retina. We generated a transgenic line of zebrafish that expresses the photoconvertible Kaede reporter driven by a her4 promoter and validated that expression of the transgene faithfully recapitulates endogenous her4 expression. Lineage tracing analysis revealed that her4-expressing cells in the INL contribute to the rod lineage, and her4 expressing cells in the CMZ are capable of generating any retinal cell type except rod photoreceptors. Our results indicate that her4 is involved in a replenishing pathway that maintains populations of stem cells in the central retina, and that the magnitude of the her4-associated proliferative response mirrors the extent of retinal damage. PMID:26616101

  10. Hydrogel formulation determines cell fate of fetal and adult neural progenitor cells

    Directory of Open Access Journals (Sweden)

    Emily R. Aurand

    2014-01-01

    Full Text Available Hydrogels provide a unique tool for neural tissue engineering. These materials can be customized for certain functions, i.e. to provide cell/drug delivery or act as a physical scaffold. Unfortunately, hydrogel complexities can negatively impact their biocompatibility, resulting in unintended consequences. These adverse effects may be combated with a better understanding of hydrogel chemical, physical, and mechanical properties, and how these properties affect encapsulated neural cells. We defined the polymerization and degradation rates and compressive moduli of 25 hydrogels formulated from different concentrations of hyaluronic acid (HA and poly(ethylene glycol (PEG. Changes in compressive modulus were driven primarily by the HA concentration. The in vitro biocompatibility of fetal-derived (fNPC and adult-derived (aNPC neural progenitor cells was dependent on hydrogel formulation. Acute survival of fNPC benefited from hydrogel encapsulation. NPC differentiation was divergent: fNPC differentiated into mostly glial cells, compared with neuronal differentiation of aNPC. Differentiation was influenced in part by the hydrogel mechanical properties. This study indicates that there can be a wide range of HA and PEG hydrogels compatible with NPC. Additionally, this is the first study comparing hydrogel encapsulation of NPC derived from different aged sources, with data suggesting that fNPC and aNPC respond dissimilarly within the same hydrogel formulation.

  11. CAM and cell fate targeting: molecular and energetic insights into cell growth and differentiation.

    Science.gov (United States)

    Ventura, Carlo

    2005-09-01

    Evidence-based medicine is switching from the analysis of single diseases at a time toward an integrated assessment of a diseased person. Complementary and alternative medicine (CAM) offers multiple holistic approaches, including osteopathy, homeopathy, chiropractic, acupuncture, herbal and energy medicine and meditation, all potentially impacting on major human diseases. It is now becoming evident that acupuncture can modify the expression of different endorphin genes and the expression of genes encoding for crucial transcription factors in cellular homeostasis. Extremely low frequency magnetic fields have been found to prime the commitment to a myocardial lineage in mouse embryonic stem cells, suggesting that magnetic energy may direct stem cell differentiation into specific cellular phenotypes without the aid of gene transfer technologies. This finding may pave the way to novel approaches in tissue engineering and regeneration. Different ginseng extracts have been shown to modulate growth and differentiation in pluripotent cells and to exert wound-healing and antitumor effects through opposing activities on the vascular system, prompting the hypothesis that ancient compounds may be the target for new logics in cell therapy. These observations and the subtle entanglement among different CAM systems suggest that CAM modalities may deeply affect both the signaling and transcriptional level of cellular homeostasis. Such a perception holds promises for a new era in CAM, prompting reproducible documentation of biological responses to CAM-related strategies and compounds. To this end, functional genomics and proteomics and the comprehension of the cell signaling networks may substantially contribute to the development of a molecular evidence-based CAM. PMID:16136206

  12. CAM and Cell Fate Targeting: Molecular and Energetic Insights into Cell Growth and Differentiation

    Directory of Open Access Journals (Sweden)

    Carlo Ventura

    2005-01-01

    Full Text Available Evidence-based medicine is switching from the analysis of single diseases at a time toward an integrated assessment of a diseased person. Complementary and alternative medicine (CAM offers multiple holistic approaches, including osteopathy, homeopathy, chiropractic, acupuncture, herbal and energy medicine and meditation, all potentially impacting on major human diseases. It is now becoming evident that acupuncture can modify the expression of different endorphin genes and the expression of genes encoding for crucial transcription factors in cellular homeostasis. Extremely low frequency magnetic fields have been found to prime the commitment to a myocardial lineage in mouse embryonic stem cells, suggesting that magnetic energy may direct stem cell differentiation into specific cellular phenotypes without the aid of gene transfer technologies. This finding may pave the way to novel approaches in tissue engineering and regeneration. Different ginseng extracts have been shown to modulate growth and differentiation in pluripotent cells and to exert wound-healing and antitumor effects through opposing activities on the vascular system, prompting the hypothesis that ancient compounds may be the target for new logics in cell therapy. These observations and the subtle entanglement among different CAM systems suggest that CAM modalities may deeply affect both the signaling and transcriptional level of cellular homeostasis. Such a perception holds promises for a new era in CAM, prompting reproducible documentation of biological responses to CAM-related strategies and compounds. To this end, functional genomics and proteomics and the comprehension of the cell signaling networks may substantially contribute to the development of a molecular evidence–based CAM.

  13. [Proliferative vitreoretinopathy: prophylactic treatment].

    Science.gov (United States)

    Chiquet, C; Rouberol, F

    2014-11-01

    Proliferative vitreoretinopathy (PVR) is a complex process. It causes contractile fibrocellular membranes that may prevent retinal reattachment. PVR therefore remains one of the most severe complications of rhegmatogenous retinal detachment (RD), with an incidence of 5-11%, and is among the most frequent causes of surgical failure (50-75%). Its severity derives from the complexity of the surgery required to treat patients and from its uncertain anatomic and functional prognosis. The first step in preventing PVR is to identify patients at risk by means of clinical and/or biological factors such as the characteristics of retinal tears (large size, number) and detachment (preexisting PVR, extent), and the use of cryotherapy. Surgeons must therefore adapt their surgical approach to the risk of PVR. The study of animal models and the natural history of the condition in humans demonstrate the importance of early antiproliferative treatment in the early stage of the disease. Combining 5-fluoro-uracil and heparin in the vitrectomy infusion lowers the rate of postoperative PVR onset in patients with PVR risk factors. The evaluation of new molecules and new dosages will lead to a decisive step in the fight against PVR. PMID:25012973

  14. Differential cytotoxicity of [123I]IUdR, [125I]IUdR and [131I]IUdR to human glioma cells in monolayer or spheroid culture: effect of proliferative heterogeneity and radiation cross-fire.

    OpenAIRE

    Neshasteh-Riz, A.; Mairs, R. J.; Angerson, W J; Stanton, P D; Reeves, J. R.; Rampling, R.; Owens, J.; Wheldon, T E

    1998-01-01

    Radioiodinated iododeoxyuridine (IUdR) is a novel, cycle-specific agent that has potential for the treatment of residual malignant glioma after surgery. As only cells in S-phase incorporate IUdR into DNA, a major limitation to this therapy is likely to be proliferative heterogeneity of the tumour cell population. Using a clonogenic end point, we have compared the toxicities of three radioiodoanalogues of IUdR--[123I]IUdR, [125I]IUdR and [131I]IUdR--to the human glioma cell line UVW, cultured ...

  15. Non-Proliferative Diabetic Retinopathy Vision Simulator

    Science.gov (United States)

    ... Retinopathy Vision Simulator Non-Proliferative Diabetic Retinopathy Vision Simulator Mar. 03, 2014 How does non-proliferative diabetic ... to form deposits. Previous Proliferative Diabetic Retinopathy Vision Simulator Related Ask an Ophthalmologist Answers Injection alternatives for ...

  16. hESC Differentiation toward an Autonomic Neuronal Cell Fate Depends on Distinct Cues from the Co-Patterning Vasculature

    Directory of Open Access Journals (Sweden)

    Lisette M. Acevedo

    2015-06-01

    Full Text Available To gain insight into the cellular and molecular cues that promote neurovascular co-patterning at the earliest stages of human embryogenesis, we developed a human embryonic stem cell model to mimic the developing epiblast. Contact of ectoderm-derived neural cells with mesoderm-derived vasculature is initiated via the neural crest (NC, not the neural tube (NT. Neurovascular co-patterning then ensues with specification of NC toward an autonomic fate requiring vascular endothelial cell (EC-secreted nitric oxide (NO and direct contact with vascular smooth muscle cells (VSMCs via T-cadherin-mediated homotypic interactions. Once a neurovascular template has been established, NT-derived central neurons then align themselves with the vasculature. Our findings reveal that, in early human development, the autonomic nervous system forms in response to distinct molecular cues from VSMCs and ECs, providing a model for how other developing lineages might coordinate their co-patterning.

  17. Tracing Conidial Fate and Measuring Host Cell Antifungal Activity Using a Reporter of Microbial Viability in the Lung

    Directory of Open Access Journals (Sweden)

    Anupam Jhingran

    2012-12-01

    Full Text Available Fluorescence can be harnessed to monitor microbial fate and to investigate functional outcomes of individual microbial cell-host cell encounters at portals of entry in native tissue environments. We illustrate this concept by introducing fluorescent Aspergillus reporter (FLARE conidia that simultaneously report phagocytic uptake and fungal viability during cellular interactions with the murine respiratory innate immune system. Our studies using FLARE conidia reveal stepwise and cell-type-specific requirements for CARD9 and Syk, transducers of C-type lectin receptor and integrin signals, in neutrophil recruitment, conidial uptake, and conidial killing in the lung. By achieving single-event resolution in defined leukocyte populations, the FLARE method enables host cell profiling on the basis of pathogen uptake and killing and may be extended to other pathogens in diverse model host organisms to query molecular, cellular, and pharmacologic mechanisms that shape host-microbe interactions.

  18. Notch-mediated post-translational control of Ngn3 protein stability regulates pancreatic patterning and cell fate commitment

    DEFF Research Database (Denmark)

    Qu, Xiaoling; Afelik, Solomon; Jensen, Jan Nygaard;

    2013-01-01

    involves transcriptional repression as previously shown, but also incorporates a novel post-translational mechanism. In addition to its ability to promote endocrine fate, we provide evidence of a competing ability of Ngn3 in the patterning of multipotent progenitor cells in turn controlling the formation......-producing beta-cells can be significantly enhanced upon induction of a pro-endocrine drive combined with the inhibition of Notch processing....... of ducts. On one hand, Ngn3 cell-intrinsically activates endocrine target genes; on the other, Ngn3 cell-extrinsically promotes lateral signaling via the Dll1>Notch>Hes1 pathway which substantially limits its ability to sustain endocrine formation. Prior to endocrine commitment, the Ngn3-mediated...

  19. Neuronal cell fate decisions:  O2 and CO2 sensing neurons require egl-13/Sox5

    DEFF Research Database (Denmark)

    Gramstrup Petersen, Jakob; Pocock, Roger David John

    2013-01-01

    We recently conducted a study that aimed to describe the differentiation mechanisms used to generate O2 and CO2 sensing neurons in C. elegans. We identified egl-13/Sox5 to be required for the differentiation of both O2 and CO2 sensing neurons. We found that egl-13 functions cell autonomously to...... drive O2 and CO2 sensing neuron fate and is therefore essential for O2 and CO2 sensing-induced behaviors. Through systematic dissection of the egl-13 promoter we identified upstream regulators of egl-13 and proposed a model of how differentiation of O2 and CO2 sensing neurons is regulated. In this...

  20. Highly variable individual donor cell fates characterize robust horizontal gene transfer of an integrative and conjugative element.

    Science.gov (United States)

    Delavat, François; Mitri, Sara; Pelet, Serge; van der Meer, Jan Roelof

    2016-06-14

    Horizontal gene transfer is an important evolutionary mechanism for bacterial adaptation. However, given the typical low transfer frequencies in a bacterial population, little is known about the fate and interplay of donor cells and the mobilized DNA during transfer. Here we study transfer of an integrative and conjugative element (ICE) among individual live bacterial cells. ICEs are widely distributed mobile DNA elements that are different than plasmids because they reside silent in the host chromosome and are maintained through vertical descent. Occasionally, ICEs become active, excise, and transmit their DNA to a new recipient, where it is reintegrated. We develop a fluorescent tool to differentiate excision, transfer, and reintegration of a model ICE named ICEclc (for carrying the clc genes for chlorocatechol metabolism) among single Pseudomonas cells by using time-lapse microscopy. We find that ICEclc activation is initiated in stationary phase cells, but excision and transfer predominantly occur only when such cells have been presented with new nutrients. Donors with activated ICE develop a number of different states, characterized by reduced cell division rates or growth arrest, persistence, or lysis, concomitant with ICE excision, and likely, ICE loss or replication. The donor cell state transitions can be described by using a stochastic model, which predicts that ICE fitness is optimal at low initiation rates in stationary phase. Despite highly variable donor cell fates, ICE transfer is remarkably robust overall, with 75% success after excision. Our results help to better understand ICE behavior and shed a new light on bacterial cellular differentiation during horizontal gene transfer. PMID:27247406

  1. Analysis on Pathogenesis of 50 Cases of Bladder Proliferative Lesions

    Institute of Scientific and Technical Information of China (English)

    陈志强; 蓝儒竹; 叶章群; 杨为民

    2003-01-01

    In order to study the pathogenesis, clinical and pathological characteristics of prolifera-tive lesions of the bladder, 50 cases of proliferative lesions of the bladder from 150 patients withcomplaints of frequency, urgency, hematuria and dysuria were subjected to cystoscopic biopsy ofthe suspicious foci in the bladder. In combination with the symptoms, urine routine and urodynam-ics, the relationship of proliferative lesions of the bladder to the inflammation and obstruction of thelower urinary tract was analyzed. Of the 50 cases of proliferative bladder lesions, 44 cases (88%)had lower urinary tract infection and 29 (58%) lower urinary tract obstruction. The patients withlower urinary tract obstruction were all complicated with infection. Three cases were associatedwith transitional cell carcinoma. Malignant cells were detected in 1 case by urinary cytologic exami-nation. Proliferative lesions of the bladder, especially those without other obvious mucosa changesunder cystoscopy, are common histological variants of urothelium in the patients with chronic in-flammation and obstruction of the lower urinary tract. Chronic inflammation and obstruction of thelower urinary tract might be the causes for proliferative lesions of the bladder. It is suggested thatdifferent treatments should be applied according to the scope and histological type of the prolifera-tive lesions.

  2. The different fate of satellite cells on conductive composite electrospun nanofibers with graphene and graphene oxide nanosheets.

    Science.gov (United States)

    Mahmoudifard, Matin; Soleimani, Masoud; Hatamie, Shadie; Zamanlui, Soheila; Ranjbarvan, Parviz; Vossoughi, Manouchehr; Hosseinzadeh, Simzar

    2016-01-01

    Electrospinning of composite polymer solutions provides fantastic potential to prepare novel nanofibers for use in a variety of applications. The addition of graphene (G) and graphene oxide (GO) nanosheets to bioactive polymers was found to enhance their conductivity and biocompatibility. Composite conductive nanofibers of polyaniline (PANI) and polyacrylonitrile (PAN) with G and GO nanosheets were prepared by an electrospinning process. The fabricated membranes were investigated by physical and chemical examinations including scanning electron microscopy (SEM), Raman spectroscopy, x-ray diffraction (XRD) and tensile assay. The muscle satellite cells enriched by a pre-plating technique were cultured in the following and their proliferation and differentiation behavior studied by MTT, Real-Time PCR assays and 4', 6-diamidino-2-phenylindole (DAPI) staining. The cultured cells on composite nanofibrous PAN/PANI-CSA/G confirmed a higher proliferation and differentiation value compared to other groups including PAN/PANI-CSA/GO and PAN/PANI-CSA scaffolds. Furthermore, the higher stiffness of the former scaffold showed a lower cell spreading as a function of stem cell activation into more proliferative cells. It is supposed that the enhanced conductivity value in addition to relative higher stiffness of the PAN/PANI-CSA/G composite nanofibers plays a favorable role for proliferation and differentiation of satellite cells. PMID:26962722

  3. Cell-to-cell signaling influences the fate of prostate cancer stem cells and their potential to generate more aggressive tumors.

    Directory of Open Access Journals (Sweden)

    Luisa Salvatori

    Full Text Available An increasing number of malignancies has been shown to be initiated and propelled by small subpopulations of cancer stem cells (CSC. However, whether tumor aggressiveness is driven by CSC and by what extent this property may be relevant within the tumor mass is still unsettled. To address this issue, we isolated a rare tumor cell population on the basis of its CD44(+CD24(- phenotype from the human androgen-independent prostate carcinoma cell line DU145 and established its CSC properties. The behavior of selected CSC was investigated with respect to the bulk DU145 cells. The injection of CSC in nude mice generated highly vascularized tumors infiltrating the adjacent tissues, showing high density of neuroendocrine cells and expressing low levels of E-cadherin and β-catenin as well as high levels of vimentin. On the contrary, when a comparable number of unsorted DU145 cells were injected the resulting tumors were less aggressive. To investigate the different features of tumors in vivo, the influence of differentiated tumor cells on CSC was examined in vitro by growing CSC in the absence or presence of conditioned medium from DU145 cells. CSC grown in permissive conditions differentiated into cell populations with features similar to those of cells held in aggressive tumors generated from CSC injection. Differently, conditioned medium induced CSC to differentiate into a cell phenotype comparable to cells of scarcely aggressive tumors originated from bulk DU145 cell injection. These findings show for the first time that CSC are able to generate differentiated cells expressing either highly or scarcely aggressive phenotype, thus influencing prostate cancer progression. The fate of CSC was determined by signals released from tumor environment. Moreover, using microarray analysis we selected some molecules which could be involved in this cell-to-cell signaling, hypothesizing their potential value for prognostic or therapeutic applications.

  4. Early postnatal respiratory viral infection alters hippocampal neurogenesis, cell fate, and neuron morphology in the neonatal piglet.

    Science.gov (United States)

    Conrad, Matthew S; Harasim, Samantha; Rhodes, Justin S; Van Alstine, William G; Johnson, Rodney W

    2015-02-01

    Respiratory viral infections are common during the neonatal period in humans, but little is known about how early-life infection impacts brain development. The current study used a neonatal piglet model as piglets have a gyrencephalic brain with growth and development similar to human infants. Piglets were inoculated with porcine reproductive and respiratory syndrome virus (PRRSV) to evaluate how chronic neuroinflammation affects hippocampal neurogenesis and neuron morphology. Piglets in the neurogenesis study received one bromodeoxyuridine injection on postnatal day (PD) 7 and then were inoculated with PRRSV. Piglets were sacrificed at PD 28 and the number of BrdU+ cells and cell fate were quantified in the dentate gyrus. PRRSV piglets showed a 24% reduction in the number of newly divided cells forming neurons. Approximately 15% of newly divided cells formed microglia, but this was not affected by sex or PRRSV. Additionally, there was a sexual dimorphism of new cell survival in the dentate gyrus where males had more cells than females, and PRRSV infection caused a decreased survival in males only. Golgi impregnation was used to characterize dentate granule cell morphology. Sholl analysis revealed that PRRSV caused a change in inner granule cell morphology where the first branch point was extended further from the cell body. Males had more complex dendritic arbors than females in the outer granule cell layer, but this was not affected by PRRSV. There were no changes to dendritic spine density or morphology distribution. These findings suggest that early-life viral infection can impact brain development. PMID:25176574

  5. Aging alters bone-fat reciprocity by shifting in vivo mesenchymal precursor cell fate towards an adipogenic lineage.

    Science.gov (United States)

    Singh, Lakshman; Brennan, Tracy A; Russell, Elizabeth; Kim, Jung-Hoon; Chen, Qijun; Brad Johnson, F; Pignolo, Robert J

    2016-04-01

    Bone marrow derived mesenchymal progenitor cells (MPCs) play an important role in bone homeostasis. Age-related changes occur in bone resulting in a decrease in bone density and a relative increase in adipocity. Although in vitro studies suggest the existence of an age-related lineage switch between osteogenic and adipogenic fates, stem cell and microenvironmental contributions to this process have not been elucidated in vivo. In order to study the effects of MPC and microenvironmental aging on functional engraftment and lineage switching, transplantation studies were performed under non-myeloablative conditions in old recipients, with donor MPCs derived from young and old green fluorescent protein (GFP) transgenic mice. Robust engraftment by young MPCs or their progeny was observed in the marrow, bone-lining region and in the matrix of young recipients; however, significantly lower engraftment was seen at the same sites in old recipients transplanted with old MPCs. Differentiation of transplanted MPCs strongly favored adipogenesis over osteogenesis in old recipients irrespective of MPC donor age, suggesting that microenvironmental alterations that occur with in vivo aging are predominately responsible for MPC lineage switching. These data indicate that aging alters bone-fat reciprocity and differentiation of mesenchymal progenitors towards an adipogenic fate. PMID:26805026

  6. Opposing Regulation of PROX1 by Interleukin-3 Receptor and NOTCH Directs Differential Host Cell Fate Reprogramming by Kaposi Sarcoma Herpes Virus

    Science.gov (United States)

    Choi, Inho; Choi, Dongwon; Chung, Hee Kyoung; Kim, Kyu Eui; Lee, Sunju; Aguilar, Berenice; Kang, Jinjoo; Park, Eunkyung; Lee, Yong Suk; Maeng, Yong-Sun; Kim, Nam Yoon; Koh, Chester J.; Hong, Young-Kwon

    2012-01-01

    Lymphatic endothelial cells (LECs) are differentiated from blood vascular endothelial cells (BECs) during embryogenesis and this physiological cell fate specification is controlled by PROX1, the master regulator for lymphatic development. When Kaposi sarcoma herpes virus (KSHV) infects host cells, it activates the otherwise silenced embryonic endothelial differentiation program and reprograms their cell fates. Interestingly, previous studies demonstrated that KSHV drives BECs to acquire a partial lymphatic phenotype by upregulating PROX1 (forward reprogramming), but stimulates LECs to regain some BEC-signature genes by downregulating PROX1 (reverse reprogramming). Despite the significance of this KSHV-induced bidirectional cell fate reprogramming in KS pathogenesis, its underlying molecular mechanism remains undefined. Here, we report that IL3 receptor alpha (IL3Rα) and NOTCH play integral roles in the host cell type-specific regulation of PROX1 by KSHV. In BECs, KSHV upregulates IL3Rα and phosphorylates STAT5, which binds and activates the PROX1 promoter. In LECs, however, PROX1 was rather downregulated by KSHV-induced NOTCH signal via HEY1, which binds and represses the PROX1 promoter. Moreover, PROX1 was found to be required to maintain HEY1 expression in LECs, establishing a reciprocal regulation between PROX1 and HEY1. Upon co-activation of IL3Rα and NOTCH, PROX1 was upregulated in BECs, but downregulated in LECs. Together, our study provides the molecular mechanism underlying the cell type-specific endothelial fate reprogramming by KSHV. PMID:22719258

  7. Peripheral Blood Monocytes as Adult Stem Cells: Molecular Characterization and Improvements in Culture Conditions to Enhance Stem Cell Features and Proliferative Potential

    OpenAIRE

    Hendrik Ungefroren; Ayman Hyder; Maren Schulze; Fawzy El-Sayed, Karim M.; Evelin Grage-Griebenow; Nussler, Andreas K.; Fred Fändrich

    2016-01-01

    Adult stem or programmable cells hold great promise in diseases in which damaged or nonfunctional cells need to be replaced. We have recently demonstrated that peripheral blood monocytes can be differentiated in vitro into cells resembling specialized cell types like hepatocytes and pancreatic beta cells. During phenotypic conversion, the monocytes downregulate monocyte/macrophage differentiation markers, being indicative of partial dedifferentiation, and are partially reprogrammed to acquire...

  8. Restoration of p53 Expression in Human Cancer Cell Lines Upregulates the Expression of Notch1: Implications for Cancer Cell Fate Determination after Genotoxic Stress

    Directory of Open Access Journals (Sweden)

    Fatouma Alimirah

    2007-05-01

    Full Text Available Following genotoxic stress, transcriptional activation of target genes by p53 tumor suppressor is critical in cell fate determination. Here we report that the restoration of p53 function in human cancer cell lines that are deficient in p53 function upregulated the expression of Notch1. Interestingly, the expression of wild-type p53 in human prostate and breast cancer cell lines correlated well with increased expression of Notch1. Furthermore, knockdown of p53 expression in cancer cells that express wild-type p53 resulted in reduced expression of Notch1. Importantly, genotoxic stress to cancer cells that resulted in activation of p53 also upregulated the expression of Notch1. Moreover, p53mediated induction of Notch1 expression was associated with stimulation of the activity of Notch-responsive reporters. Notably, p53 differentially regulated the expression of Notch family members: expression of Notch2 and Notch4 was not induced by p53. Significantly, treatment of cells with gamma secretase inhibitor, an inhibitor of Notch signaling, increased susceptibility to apoptosis in response to genotoxic stress. Together, our observations suggest that p53mediated upregulation of Notch1 expression in human cancer cell lines contributes to cell fate determination after genotoxic stress.

  9. Imaging long-term fate of intramyocardially implanted mesenchymal stem cells in a porcine myocardial infarction model.

    Directory of Open Access Journals (Sweden)

    Emerson C Perin

    Full Text Available The long-term fate of stem cells after intramyocardial delivery is unknown. We used noninvasive, repetitive PET/CT imaging with [(18F]FEAU to monitor the long-term (up to 5 months spatial-temporal dynamics of MSCs retrovirally transduced with the sr39HSV1-tk gene (sr39HSV1-tk-MSC and implanted intramyocardially in pigs with induced acute myocardial infarction. Repetitive [(18F]FEAU PET/CT revealed a biphasic pattern of sr39HSV1-tk-MSC dynamics; cell proliferation peaked at 33-35 days after injection, in periinfarct regions and the major cardiac lymphatic vessels and lymph nodes. The sr39HSV1-tk-MSC-associated [(18F]FEAU signals gradually decreased thereafter. Cardiac lymphography studies using PG-Gd-NIRF813 contrast for MRI and near-infrared fluorescence imaging showed rapid clearance of the contrast from the site of intramyocardial injection through the subepicardial lymphatic network into the lymphatic vessels and periaortic lymph nodes. Immunohistochemical analysis of cardiac tissue obtained at 35 and 150 days demonstrated several types of sr39HSV1-tk expressing cells, including fibro-myoblasts, lymphovascular cells, and microvascular and arterial endothelium. In summary, this study demonstrated the feasibility and sensitivity of [(18F]FEAU PET/CT imaging for long-term, in-vivo monitoring (up to 5 months of the fate of intramyocardially injected sr39HSV1-tk-MSC cells. Intramyocardially transplanted MSCs appear to integrate into the lymphatic endothelium and may help improve myocardial lymphatic system function after MI.

  10. ANTI-PROLIFERATIVE ACTIVITY OF TINOSPORA CORDIFOLIA DETERMINED BY CELL COUNT AND TRYPAN BLUE DYE EXCLUSION METHOD IN MCF-7 CELLS

    OpenAIRE

    Sakthi Priya M*, KV Venkateswaran, LN Mathuram, M ParthibanT and Vijayanand

    2013-01-01

    An in-vitro study was performed in mammary tumor cell line MCF-7 to find out the antiproliferative activity of aqueous and hydro-alcoholic extracts of Guduchi Tinospora cordifolia, each at three different doses viz., 200µg/ml, 400µg/ml and 600µg/ml. Their effects on the proliferation of cells were analyzed by cell count assay and cell viability was detected by using trypan blue dye exclusion method. Both of the extracts produced significant decrease in cell count and cell viability, with maxi...

  11. Control of flowering and cell fate by LIF2, an RNA binding partner of the polycomb complex component LHP1.

    Directory of Open Access Journals (Sweden)

    David Latrasse

    Full Text Available Polycomb Repressive Complexes (PRC modulate the epigenetic status of key cell fate and developmental regulators in eukaryotes. The chromo domain protein like heterochromatin protein1 (LHP1 is a subunit of a plant PRC1-like complex in Arabidopsis thaliana and recognizes histone H3 lysine 27 trimethylation, a silencing epigenetic mark deposited by the PRC2 complex. We have identified and studied an LHP1-Interacting Factor2 (LIF2. LIF2 protein has RNA recognition motifs and belongs to the large hnRNP protein family, which is involved in RNA processing. LIF2 interacts in vivo, in the cell nucleus, with the LHP1 chromo shadow domain. Expression of LIF2 was detected predominantly in vascular and meristematic tissues. Loss-of-function of LIF2 modifies flowering time, floral developmental homeostasis and gynoecium growth determination. lif2 ovaries have indeterminate growth and produce ectopic inflorescences with severely affected flowers showing proliferation of ectopic stigmatic papillae and ovules in short-day conditions. To look at how LIF2 acts relative to LHP1, we conducted transcriptome analyses in lif2 and lhp1 and identified a common set of deregulated genes, which showed significant enrichment in stress-response genes. By comparing expression of LHP1 targets in lif2, lhp1 and lif2 lhp1 mutants we showed that LIF2 can either antagonize or act with LHP1. Interestingly, repression of the FLC floral transcriptional regulator in lif2 mutant is accompanied by an increase in H3K27 trimethylation at the locus, without any change in LHP1 binding, suggesting that LHP1 is targeted independently from LIF2 and that LHP1 binding does not strictly correlate with gene expression. LIF2, involved in cell identity and cell fate decision, may modulate the activity of LHP1 at specific loci, during specific developmental windows or in response to environmental cues that control cell fate determination. These results highlight a novel link between plant RNA

  12. High-definition mapping of retroviral integration sites defines the fate of allogeneic T cells after donor lymphocyte infusion.

    Science.gov (United States)

    Cattoglio, Claudia; Maruggi, Giulietta; Bartholomae, Cynthia; Malani, Nirav; Pellin, Danilo; Cocchiarella, Fabienne; Magnani, Zulma; Ciceri, Fabio; Ambrosi, Alessandro; von Kalle, Christof; Bushman, Frederic D; Bonini, Chiara; Schmidt, Manfred; Mavilio, Fulvio; Recchia, Alessandra

    2010-01-01

    The infusion of donor lymphocytes transduced with a retroviral vector expressing the HSV-TK suicide gene in patients undergoing hematopoietic stem cell transplantation for leukemia/lymphoma promotes immune reconstitution and prevents infections and graft-versus-host disease. Analysis of the clonal dynamics of genetically modified lymphocytes in vivo is of crucial importance to understand the potential genotoxic risk of this therapeutic approach. We used linear amplification-mediated PCR and pyrosequencing to build a genome-wide, high-definition map of retroviral integration sites in the genome of peripheral blood T cells from two different donors and used gene expression profiling and bioinformatics to associate integration clusters to transcriptional activity and to genetic and epigenetic features of the T cell genome. Comparison with matched random controls and with integrations obtained from CD34(+) hematopoietic stem/progenitor cells showed that integration clusters occur within chromatin regions bearing epigenetic marks associated with active promoters and regulatory elements in a cell-specific fashion. Analysis of integration sites in T cells obtained ex vivo two months after infusion showed no evidence of integration-related clonal expansion or dominance, but rather loss of cells harboring integration events interfering with RNA post-transcriptional processing. The study shows that high-definition maps of retroviral integration sites are a powerful tool to analyze the fate of genetically modified T cells in patients and the biological consequences of retroviral transduction. PMID:21203516

  13. Exine dehiscing induces rape microspore polarity, which results in different daughter cell fate and fixes the apical–basal axis of the embryo

    OpenAIRE

    Tang, Xingchun; Liu, Yuan; He, Yuqing; Ma, Ligang; Sun, Meng-xiang

    2012-01-01

    The roles of cell polarity and the first asymmetric cell division during early embryogenesis in apical–basal cell fate determination remain unclear. Previously, a novel Brassica napus microspore embryogenesis system was established, by which rape exine-dehisced microspores were induced by physical stress. Unlike traditional microspore culture, cell polarity and subsequent asymmetric division appeared in the exine-dehisced microspore, which finally developed into a typical embryo with a suspen...

  14. A specific box switches the cell fate determining activity of XOTX2 and XOTX5b in the Xenopus retina

    Directory of Open Access Journals (Sweden)

    He Rong-Qiao

    2007-06-01

    Full Text Available Abstract Background Otx genes, orthologues of the Drosophila orthodenticle gene (otd, play crucial roles in vertebrate brain development. In the Xenopus eye, Xotx2 and Xotx5b promote bipolar and photoreceptor cell fates, respectively. The molecular basis of their differential action is not completely understood, though the carboxyl termini of the two proteins seem to be crucial. To define the molecular domains that make the action of these proteins so different, and to determine whether their retinal abilities are shared by Drosophila OTD, we performed an in vivo molecular dissection of their activity by transfecting retinal progenitors with several wild-type, deletion and chimeric constructs of Xotx2, Xotx5b and otd. Results We identified a small 8–10 amino acid divergent region, directly downstream of the homeodomain, that is crucial for the respective activities of XOTX2 and XOTX5b. In lipofection experiments, the exchange of this 'specificity box' completely switches the retinal activity of XOTX5b into that of XOTX2 and vice versa. Moreover, the insertion of this box into Drosophila OTD, which has no effect on retinal cell fate, endows it with the specific activity of either XOTX protein. Significantly, in cell transfection experiments, the diverse ability of XOTX2 and XOTX5b to synergize with NRL, a cofactor essential for vertebrate rod development, to transactivate the rhodopsin promoter is also switched depending on the box. We also show by GST-pull down that XOTX2 and XOTX5b differentially interact with NRL, though this property is not strictly dependent on the box. Conclusion Our data provide molecular evidence on how closely related homeodomain gene products can differentiate their functions to regulate distinct cell fates. A small 'specificity box' is both necessary and sufficient to confer on XOTX2 and XOTX5b their distinct activities in the developing frog retina and to convert the neutral orthologous OTD protein of Drosophila

  15. Fates of Microcystis aeruginosa Cells and Associated Microcystins in Sediment and the Effect of Coagulation Process on Them

    Directory of Open Access Journals (Sweden)

    Xiaoguo Chen

    2013-12-01

    Full Text Available During toxic Microcystis aeruginosa blooms, large amounts of cells can enter sediment through natural settlement, and coagulation treatment used to control water blooms can enhance the accumulation of cells. However, the current understanding of the fates of these cells and associated microcystins (MCs, as well as the effect of coagulation treatment on these factors, is limited. The results of the present study show that Microcystis aeruginosa cells in sediment were steadily decomposed under experimental conditions, and that they completely disappeared within 28 days. The major MCs released from settled cells were immediately degraded in sediment, and microbial degradation may be the main mechanism involved in this process. Coagulation treatment with PAC (polyaluminium chloride + sepiolite can efficiently remove Microcystis aeruginosa cells from the water column and prevent their re-invasion. Furthermore, coagulation treatment with PAC + sepiolite had no significant effect on the release and decomposition of MCs and, thus, will not enhance the MCs pollution. However, coagulation treatment can accelerate the nutrient cycle by enhancing the settlement of cells. More attention should be paid to the effect on nutrient cycle when coagulation treatment is used for restoration of aquatic ecosystems.

  16. Type I and Type II Interferon Coordinately Regulate Suppressive Dendritic Cell Fate and Function during Viral Persistence

    Science.gov (United States)

    Cunningham, Cameron R.; Champhekar, Ameya; Tullius, Michael V.; Dillon, Barbara Jane; Zhen, Anjie; de la Fuente, Justin Rafael; Herskovitz, Jonathan; Elsaesser, Heidi; Snell, Laura M.; Wilson, Elizabeth B.; de la Torre, Juan Carlos; Kitchen, Scott G.; Horwitz, Marcus A.; Bensinger, Steven J.; Smale, Stephen T.; Brooks, David G.

    2016-01-01

    Persistent viral infections are simultaneously associated with chronic inflammation and highly potent immunosuppressive programs mediated by IL-10 and PDL1 that attenuate antiviral T cell responses. Inhibiting these suppressive signals enhances T cell function to control persistent infection; yet, the underlying signals and mechanisms that program immunosuppressive cell fates and functions are not well understood. Herein, we use lymphocytic choriomeningitis virus infection (LCMV) to demonstrate that the induction and functional programming of immunosuppressive dendritic cells (DCs) during viral persistence are separable mechanisms programmed by factors primarily considered pro-inflammatory. IFNγ first induces the de novo development of naive monocytes into DCs with immunosuppressive potential. Type I interferon (IFN-I) then directly targets these newly generated DCs to program their potent T cell immunosuppressive functions while simultaneously inhibiting conventional DCs with T cell stimulating capacity. These mechanisms of monocyte conversion are constant throughout persistent infection, establishing a system to continuously interpret and shape the immunologic environment. MyD88 signaling was required for the differentiation of suppressive DCs, whereas inhibition of stimulatory DCs was dependent on MAVS signaling, demonstrating a bifurcation in the pathogen recognition pathways that promote distinct elements of IFN-I mediated immunosuppression. Further, a similar suppressive DC origin and differentiation was also observed in Mycobacterium tuberculosis infection, HIV infection and cancer. Ultimately, targeting the underlying mechanisms that induce immunosuppression could simultaneously prevent multiple suppressive signals to further restore T cell function and control persistent infections. PMID:26808628

  17. Single-cell mass cytometry reveals intracellular survival/proliferative signaling in FLT3-ITD-mutated AML stem/progenitor cells

    OpenAIRE

    Han, Lina; Qiu, Peng; Zeng, Zhihong; Jorgensen, Jeffrey L.; Mak, Duncan H; Burks, Jared K.; Schober, Wendy; McQueen, Teresa J; Cortes, Jorge; Tanner, Scott D; Roboz, Gail J; Kantarjian, Hagop M; Kornblau, Steven M.; Guzman, Monica L.; Andreeff, Michael

    2015-01-01

    Understanding the unique phenotypes and complex signaling pathways of leukemia stem cells (LSCs) will provide insights and druggable targets that can be used to eradicate acute myeloid leukemia (AML). Current work on AML LSCs is limited by the number of parameters that conventional flow cytometry (FCM) can analyze because of cell autofluorescence and fluorescent dye spectral overlap. Single-cell mass cytometry (CyTOF) substitutes rare earth elements for fluorophores to label antibodies, which...

  18. Engineering hyaluronic acid hydrogel degradation to control cellular interactions and adult stem cell fate in 3D

    Science.gov (United States)

    Khetan, Sudhir

    The design and implementation of extracellular matrix (ECM)-mimetic hydrogels for tissue engineering (TE) applications requires an intensive understanding of cell-material interactions, including matrix remodeling and stem cell differentiation. However, the influence of microenvironmental cues, e.g., matrix biodegradability, on cell behavior in vitro has not been well studied in the case of direct cell encapsulation within 3-dimensional (3D) hydrogels. To address these issues, a facile sequential crosslinking technique was developed that provides spatial and temporal control of 3D hydrogel degradability to investigate the importance of material design on cell behavior. Specifically, hydrogels were synthesized from hyaluronic acid (HA) macromers in a sequential process: (1) a primary Michael-type addition crosslinking using cell adhesive and matrix metalloprotease (MMP)-degradable oligopeptides to consume a portion of total reactive groups and resulting in "-UV" hydrogels permissive to cell-mediated degradation, followed by (2) a secondary, light initiated free-radical crosslinking to consume remaining reactive groups and "switch" the network to a non-degradable structure ("+UV") via the addition of non-degradable kinetic chains. Using this approach, we demonstrated control of encapsulated hMSC spreading by varying the crosslink type (i.e., the relative hydrogel biodegradability), including with spatial control. Upon incubation with bipotential soluble differentiation factors, these same degradation-mediated spreading cues resulted in an hMSC differentiation fate switch within -UV versus +UV environments. Follow-up studies demonstrated that degradation-mediated traction generation, rather than matrix mechanics or cell morphology, is the critical biophysical signal determining hMSC fate. Sequentially crosslinked HA hydrogels were also studied for the capacity to support remodeling by in vivo and ex vivo tissues, including with spatial control, toward tissue

  19. Four and a Half LIM Domains 1b (Fhl1b) Is Essential for Regulating the Liver versus Pancreas Fate Decision and for β-Cell Regeneration.

    Science.gov (United States)

    Xu, Jin; Cui, Jiaxi; Del Campo, Aranzazu; Shin, Chong Hyun

    2016-02-01

    The liver and pancreas originate from overlapping embryonic regions, and single-cell lineage tracing in zebrafish has shown that Bone morphogenetic protein 2b (Bmp2b) signaling is essential for determining the fate of bipotential hepatopancreatic progenitors towards the liver or pancreas. Despite its pivotal role, the gene regulatory networks functioning downstream of Bmp2b signaling in this process are poorly understood. We have identified four and a half LIM domains 1b (fhl1b), which is primarily expressed in the prospective liver anlage, as a novel target of Bmp2b signaling. fhl1b depletion compromised liver specification and enhanced induction of pancreatic cells from endodermal progenitors. Conversely, overexpression of fhl1b favored liver specification and inhibited induction of pancreatic cells. By single-cell lineage tracing, we showed that fhl1b depletion led lateral endodermal cells, destined to become liver cells, to become pancreatic cells. Reversely, when fhl1b was overexpressed, medially located endodermal cells, fated to differentiate into pancreatic and intestinal cells, contributed to the liver by directly or indirectly modulating the discrete levels of pdx1 expression in endodermal progenitors. Moreover, loss of fhl1b increased the regenerative capacity of β-cells by increasing pdx1 and neurod expression in the hepatopancreatic ductal system. Altogether, these data reveal novel and critical functions of Fhl1b in the hepatic versus pancreatic fate decision and in β-cell regeneration. PMID:26845333

  20. Four and a Half LIM Domains 1b (Fhl1b Is Essential for Regulating the Liver versus Pancreas Fate Decision and for β-Cell Regeneration.

    Directory of Open Access Journals (Sweden)

    Jin Xu

    2016-02-01

    Full Text Available The liver and pancreas originate from overlapping embryonic regions, and single-cell lineage tracing in zebrafish has shown that Bone morphogenetic protein 2b (Bmp2b signaling is essential for determining the fate of bipotential hepatopancreatic progenitors towards the liver or pancreas. Despite its pivotal role, the gene regulatory networks functioning downstream of Bmp2b signaling in this process are poorly understood. We have identified four and a half LIM domains 1b (fhl1b, which is primarily expressed in the prospective liver anlage, as a novel target of Bmp2b signaling. fhl1b depletion compromised liver specification and enhanced induction of pancreatic cells from endodermal progenitors. Conversely, overexpression of fhl1b favored liver specification and inhibited induction of pancreatic cells. By single-cell lineage tracing, we showed that fhl1b depletion led lateral endodermal cells, destined to become liver cells, to become pancreatic cells. Reversely, when fhl1b was overexpressed, medially located endodermal cells, fated to differentiate into pancreatic and intestinal cells, contributed to the liver by directly or indirectly modulating the discrete levels of pdx1 expression in endodermal progenitors. Moreover, loss of fhl1b increased the regenerative capacity of β-cells by increasing pdx1 and neurod expression in the hepatopancreatic ductal system. Altogether, these data reveal novel and critical functions of Fhl1b in the hepatic versus pancreatic fate decision and in β-cell regeneration.

  1. Single-cell mass cytometry reveals intracellular survival/proliferative signaling in FLT3-ITD-mutated AML stem/progenitor cells.

    Science.gov (United States)

    Han, Lina; Qiu, Peng; Zeng, Zhihong; Jorgensen, Jeffrey L; Mak, Duncan H; Burks, Jared K; Schober, Wendy; McQueen, Teresa J; Cortes, Jorge; Tanner, Scott D; Roboz, Gail J; Kantarjian, Hagop M; Kornblau, Steven M; Guzman, Monica L; Andreeff, Michael; Konopleva, Marina

    2015-04-01

    Understanding the unique phenotypes and complex signaling pathways of leukemia stem cells (LSCs) will provide insights and druggable targets that can be used to eradicate acute myeloid leukemia (AML). Current work on AML LSCs is limited by the number of parameters that conventional flow cytometry (FCM) can analyze because of cell autofluorescence and fluorescent dye spectral overlap. Single-cell mass cytometry (CyTOF) substitutes rare earth elements for fluorophores to label antibodies, which allows measurements of up to 120 parameters in single cells without correction for spectral overlap. The aim of this study was the evaluation of intracellular signaling in antigen-defined stem/progenitor cell subsets in primary AML. CyTOF and conventional FCM yielded comparable results on LSC phenotypes defined by CD45, CD34, CD38, CD123, and CD99. Intracellular phosphoprotein responses to ex vivo cell signaling inhibitors and cytokine stimulation were assessed in myeloid leukemia cell lines and one primary AML sample. CyTOF and conventional FCM results were confirmed by western blotting. In the primary AML sample, we investigated the cell responses to ex vivo stimulation with stem cell factor and BEZ235-induced inhibition of PI3K and identified activation patterns in multiple PI3K downstream signaling pathways including p-4EBP1, p-AKT, and p-S6, particularly in CD34(+) subsets. We evaluated multiple signaling pathways in antigen-defined subpopulations in primary AML cells with FLT3-ITD mutations. The data demonstrated the heterogeneity of cell phenotype distribution and distinct patterns of signaling activation across AML samples and between AML and normal samples. The mTOR targets p-4EBP1 and p-S6 were exclusively found in FLT3-ITD stem/progenitor cells, but not in their normal counterparts, suggesting both as novel targets in FLT3 mutated AML. Our data suggest that CyTOF can identify functional signaling pathways in antigen-defined subpopulations in primary AML, which may

  2. Evaluation of the effects of ethinylestradiol on sexual differentiation in the olvas-GFP/STII-YI medaka (transgenic Oryzias latipes) strain as estimated by proliferative activity of germ cells

    International Nuclear Information System (INIS)

    We evaluated the effects of 17(-ethinylestradiol (EE2) on sexual differentiation in transgenic olvas-GFP/STII-YI medaka (Oryzias latipes) in terms of the proliferative activity of germ cells. This strain contains the green fluorescent protein (GFP) gene fused to the regulatory region of the medaka vasa gene, and germ cell-specific expression of GFP can be visualized in living (transparent) individuals. From 0 days post-hatch (0 dph) onwards, juveniles were exposed to graded concentrations of EE2 (25.2-1710 ng/L) for 35 days. The gonads of live specimens were monitored by measuring their size and calculating their GFP-fluorescence area. GFP-fluorescent area in control females was about 10 times that in control males at 10 days posthatch (dph) whereas the gonadal size of 10 dph males that had been exposed to 158 ng/L of EE2 significantly increased up to twice the size of control males, indicating that abnormal sexual differentiation towards female might occur in these individuals. Histological examination and identification of the sex-linked marker SL1 indicated that male to female sex reversal occurred at EE2 exposure ≥45.1 ng/L at 35 dph. These results suggest that observation of proliferative activity of germ cells in the olvas-GFP/STII-YI strain could be applied to facilitated screening fish model to detect adverse effects on sexual differentiation as early as 10 dph juveniles.

  3. Sox17-Mediated XEN Cell Conversion Identifies Dynamic Networks Controlling Cell-Fate Decisions in Embryo-Derived Stem Cells

    OpenAIRE

    McDonald, Angela C.H.; Steffen Biechele; Janet Rossant; William L. Stanford

    2014-01-01

    Little is known about the gene regulatory networks (GRNs) distinguishing extraembryonic endoderm (ExEn) stem (XEN) cells from those that maintain the extensively characterized embryonic stem cell (ESC). An intriguing network candidate is Sox17, an essential transcription factor for XEN derivation and self-renewal. Here, we show that forced Sox17 expression drives ESCs toward ExEn, generating XEN cells that contribute to ExEn when placed back into early mouse embryos. Transient Sox17 expressio...

  4. The ETS domain transcriptional repressor Anterior open inhibits MAP kinase and Wingless signaling to couple tracheal cell fate with branch identity.

    Science.gov (United States)

    Caviglia, Sara; Luschnig, Stefan

    2013-03-01

    Cells at the tips of budding branches in the Drosophila tracheal system generate two morphologically different types of seamless tubes. Terminal cells (TCs) form branched lumenized extensions that mediate gas exchange at target tissues, whereas fusion cells (FCs) form ring-like connections between adjacent tracheal metameres. Each tracheal branch contains a specific set of TCs, FCs, or both, but the mechanisms that select between the two tip cell types in a branch-specific fashion are not clear. Here, we show that the ETS domain transcriptional repressor anterior open (aop) is dispensable for directed tracheal cell migration, but plays a key role in tracheal tip cell fate specification. Whereas aop globally inhibits TC and FC specification, MAPK signaling overcomes this inhibition by triggering degradation of Aop in tip cells. Loss of aop function causes excessive FC and TC specification, indicating that without Aop-mediated inhibition, all tracheal cells are competent to adopt a specialized fate. We demonstrate that Aop plays a dual role by inhibiting both MAPK and Wingless signaling, which induce TC and FC fate, respectively. In addition, the branch-specific choice between the two seamless tube types depends on the tracheal branch identity gene spalt major, which is sufficient to inhibit TC specification. Thus, a single repressor, Aop, integrates two different signals to couple tip cell fate selection with branch identity. The switch from a branching towards an anastomosing tip cell type may have evolved with the acquisition of a main tube that connects separate tracheal primordia to generate a tubular network. PMID:23444354

  5. Sexual Fate Change of XX Germ Cells Caused by the Deletion of SMAD4 and STRA8 Independent of Somatic Sex Reprogramming.

    Science.gov (United States)

    Wu, Quan; Fukuda, Kurumi; Kato, Yuzuru; Zhou, Zhi; Deng, Chu-Xia; Saga, Yumiko

    2016-09-01

    The differential programming of sperm and eggs in gonads is a fundamental topic in reproductive biology. Although the sexual fate of germ cells is believed to be determined by signaling factors from sexually differentiated somatic cells in fetal gonads, the molecular mechanism that determines germ cell fate is poorly understood. Herein, we show that mothers against decapentaplegic homolog 4 (SMAD4) in germ cells is required for female-type differentiation. Germ cells in Smad4-deficient ovaries respond to retinoic acid signaling but fail to undergo meiotic prophase I, which coincides with the weaker expression of genes required for follicular formation, indicating that SMAD4 signaling is essential for oocyte differentiation and meiotic progression. Intriguingly, germline-specific deletion of Smad4 in Stra8-null female germ cells resulted in the up-regulation of genes required for male gonocyte differentiation, including Nanos2 and PLZF, suggesting the initiation of male-type differentiation in ovaries. Moreover, our transcriptome analyses of mutant ovaries revealed that the sex change phenotype is achieved without global gene expression changes in somatic cells. Our results demonstrate that SMAD4 and STRA8 are essential factors that regulate the female fate of germ cells. PMID:27606421

  6. Evaluating the uptake and intracellular fate of polystyrene nanoparticles by primary and hepatocyte cell lines in vitro

    International Nuclear Information System (INIS)

    Nanoparticles (NPs) are being used within diverse applications such as medicines, clothing, cosmetics and food. In order to promote the safe development of such nanotechnologies it is essential to assess the potential adverse health consequences associated with human exposure. The liver is recognised as a target site for NP toxicity, due to NP accumulation within this organ subsequent to injection, inhalation or instillation. The uptake of fluorescent polystyrene carboxylated particles (20 nm or 200 nm diameter) by hepatocytes was determined using confocal microscopy; with cells imaged 'live' during particle exposure or after exposure within fixed cells. Comparisons between the uptake of polystyrene particles by primary rat hepatocytes, and human hepatocyte cell lines (C3A and HepG2) were made. Uptake of particles by hepatocytes was size, time, and serum dependent. Specifically, the uptake of 200 nm particles was limited, but 20 nm NPs were internalised by all cell types from 10 min onwards. At 10 min, 20 nm NP fluorescence co-localised with the tubulin cytoskeleton staining; after 30 min NP fluorescence compartmentalised into structures located within and/or between cells. The fate of internalised NPs was considered and they were not contained within early endosomes or lysosomes, but within mitochondria of cell lines. NPs accumulated within bile canaliculi to a limited extent, which suggests that NPs can be eliminated within bile. This is in keeping with the finding that gold NPs were eliminated in bile following intravenous injection into rats. The findings were, in the main, comparable between primary rat hepatocytes and the different human hepatocyte cell lines.

  7. Cellular size as a means of tracking mTOR activity and cell fate of CD4+ T cells upon antigen recognition.

    Directory of Open Access Journals (Sweden)

    Kristen N Pollizzi

    Full Text Available mTOR is a central integrator of metabolic and immunological stimuli, dictating immune cell activation, proliferation and differentiation. In this study, we demonstrate that within a clonal population of activated T cells, there exist both mTORhi and mTORlo cells exhibiting highly divergent metabolic and immunologic functions. By taking advantage of the role of mTOR activation in controlling cellular size, we demonstrate that upon antigen recognition, mTORhi CD4+ T cells are destined to become highly glycolytic effector cells. Conversely, mTORlo T cells preferentially develop into long-lived cells that express high levels of Bcl-2, CD25, and CD62L. Furthermore, mTORlo T cells have a greater propensity to differentiate into suppressive Foxp3+ T regulatory cells, and this paradigm was also observed in human CD4+ T cells. Overall, these studies provide the opportunity to track the development of effector and memory T cells from naïve precursors, as well as facilitate the interrogation of immunologic and metabolic programs that inform these fates.

  8. Proliferative glomerulonephritis and primary antiphospholipid syndrome

    International Nuclear Information System (INIS)

    Little is known regarding the association of primary antiphospholipid syndrome (APLS) and proliferative glomerulonephiritis (GN). We describe a biopsy-documented case with primary APLS and proliferative (GN) with no evidence of thrombotic microangiopathy (TMA), and in the absence of other manifestations of systematic lupus erythematosus (SLE). She presented initially with left popliteal deep venous thrombosis and nephrotic syndrome. Her first pregnancy at the age of 26 years resulted in the intra-uterine fetal death at term. Two subsequent pregnancies ended up with miscarriages at 3 and 4 months of gestation. Urinalysis revealed glomerular red blood cells of 1.0000.000/ml and granular cast; proteinuria of 13.4grams/24 hours, which was non-selective; hemoglobin 12 gm/dl, normal white blood cell and platelets; serum albumin 2.6gm/dl; anti-nuclear antibody (ANA) and anti DNA were negative and complement levels normal. Lupus anticoagulant was positive leading to a diagnosis of primary APLS. The biopsy findings were consistent with membranoproliferative GN. She continued to have steroid-resistant proteinuria, but stable renal function after a 12-year follow up period. She had 2 pregnancies during this period and was delivered at term using caesarian section. She received heparin during the pregnancies. Later she developed hypertension easily controlled by atenolol. This case provides evidence that primary APLS can be associated with proliferative GN due to immune deposits and not only TMA as previously reported, and in the complete absence of SLE. Performing more renal biopsies in this group of patients may disclose a greater prevalence of proleferative GN and may help in devising a rationale for treatment. (author)

  9. Energy metabolism and energy-sensing pathways in mammalian embryonic and adult stem cell fate

    OpenAIRE

    Rafalski, Victoria A.; Mancini, Elena; Brunet, Anne

    2012-01-01

    Metabolism is influenced by age, food intake, and conditions such as diabetes and obesity. How do physiological or pathological metabolic changes influence stem cells, which are crucial for tissue homeostasis? This Commentary reviews recent evidence that stem cells have different metabolic demands than differentiated cells, and that the molecular mechanisms that control stem cell self-renewal and differentiation are functionally connected to the metabolic state of the cell and the surrounding...

  10. Modeling reveals bistability and low-pass filtering in the network module determining blood stem cell fate.

    Directory of Open Access Journals (Sweden)

    Jatin Narula

    2010-05-01

    Full Text Available Combinatorial regulation of gene expression is ubiquitous in eukaryotes with multiple inputs converging on regulatory control elements. The dynamic properties of these elements determine the functionality of genetic networks regulating differentiation and development. Here we propose a method to quantitatively characterize the regulatory output of distant enhancers with a biophysical approach that recursively determines free energies of protein-protein and protein-DNA interactions from experimental analysis of transcriptional reporter libraries. We apply this method to model the Scl-Gata2-Fli1 triad-a network module important for cell fate specification of hematopoietic stem cells. We show that this triad module is inherently bistable with irreversible transitions in response to physiologically relevant signals such as Notch, Bmp4 and Gata1 and we use the model to predict the sensitivity of the network to mutations. We also show that the triad acts as a low-pass filter by switching between steady states only in response to signals that persist for longer than a minimum duration threshold. We have found that the auto-regulation loops connecting the slow-degrading Scl to Gata2 and Fli1 are crucial for this low-pass filtering property. Taken together our analysis not only reveals new insights into hematopoietic stem cell regulatory network functionality but also provides a novel and widely applicable strategy to incorporate experimental measurements into dynamical network models.

  11. RhoA determines lineage fate of mesenchymal stem cells by modulating CTGF–VEGF complex in extracellular matrix

    Science.gov (United States)

    Li, Changjun; Zhen, Gehua; Chai, Yu; Xie, Liang; Crane, Janet L.; Farber, Emily; Farber, Charles R.; Luo, Xianghang; Gao, Peisong; Cao, Xu; Wan, Mei

    2016-01-01

    Mesenchymal stem cells (MSCs) participate in the repair/remodelling of many tissues, where MSCs commit to different lineages dependent on the cues in the local microenvironment. Here we show that TGFβ-activated RhoA/ROCK signalling functions as a molecular switch regarding the fate of MSCs in arterial repair/remodelling after injury. MSCs differentiate into myofibroblasts when RhoA/ROCK is turned on, endothelial cells when turned off. The former is pathophysiologic resulting in intimal hyperplasia, whereas the latter is physiological leading to endothelial repair. Further analysis revealed that MSC RhoA activation promotes formation of an extracellular matrix (ECM) complex consisting of connective tissue growth factor (CTGF) and vascular endothelial growth factor (VEGF). Inactivation of RhoA/ROCK in MSCs induces matrix metalloproteinase-3-mediated CTGF cleavage, resulting in VEGF release and MSC endothelial differentiation. Our findings uncover a novel mechanism by which cell–ECM interactions determine stem cell lineage specificity and offer additional molecular targets to manipulate MSC-involved tissue repair/regeneration. PMID:27126736

  12. Chromatin dynamics in pollen mother cells underpin a common scenario at the somatic-to-reproductive fate transition of both the male and female lineages in Arabidopsis

    OpenAIRE

    She, Wenjing; Baroux, Célia

    2015-01-01

    Unlike animals, where the germline is established early during embryogenesis, plants set aside their reproductive lineage late in development in dedicated floral organs. The specification of pollen mother cells (PMC) committed to meiosis takes place in the sporogenous tissue in anther locules and marks the somatic-to-reproductive cell fate transition toward the male reproductive lineage. Here we show that Arabidopsis PMC differentiation is accompanied by large-scale changes in chromatin organ...

  13. Nkx2.2 and Nkx2.9 Are the Key Regulators to Determine Cell Fate of Branchial and Visceral Motor Neurons in Caudal Hindbrain

    OpenAIRE

    Jarrar, Wassan; Dias, Jose M.; Ericson, Johan; Arnold, Hans-Henning; Holz, Andreas

    2015-01-01

    Cranial motor nerves in vertebrates are comprised of the three principal subtypes of branchial, visceral, and somatic motor neurons, which develop in typical patterns along the anteroposterior and dorsoventral axes of hindbrain. Here we demonstrate that the formation of branchial and visceral motor neurons critically depends on the transcription factors Nkx2.2 and Nkx2.9, which together determine the cell fate of neuronal progenitor cells. Disruption of both genes in mouse embryos results in ...

  14. Fate of Mammalian Cochlear Hair Cells and Stereocilia after Loss of the Stereocilia

    OpenAIRE

    Jia, Shuping; Yang, Shiming; Guo, Weiwei; David Z Z He

    2009-01-01

    Cochlear hair cells transduce mechanical stimuli into electrical activity. The site of hair cell transduction is the hair bundle, an array of stereocilia with different height arranged in a staircase. Tip links connect the apex of each stereocilium to the side of its taller neighbor. The hair bundle and tip links of hair cells are susceptible to acoustic trauma and ototoxic drugs. It has been shown that hair cells in lower vertebrates and in the mammalian vestibular system may survive bundle ...

  15. Estrogen signaling in the proliferative endometrium: implications in endometriosis

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Pereira da Costa e Silva

    2016-02-01

    Full Text Available SUMMARY Even though the physiological role of estrogen in the female reproductive cycle and endometrial proliferative phase is well established, the signaling pathways by which estrogen exerts its action in the endometrial tissue are still little known. In this regard, advancements in cell culture techniques and maintenance of endometrial cells in cultures enabled the discovery of new signaling mechanisms activated by estrogen in the normal endometrium and in endometriosis. This review aims to present the recent findings in the genomic and non-genomic estrogen signaling pathways in the proliferative human endometrium specifically associated with the pathogenesis and development of endometriosis.

  16. The Phenotypic Fate of Bone Marrow-Derived Stem Cells in Acute Kidney Injury

    Directory of Open Access Journals (Sweden)

    Guowei Feng

    2013-11-01

    Full Text Available Background: Despite increasing attention on the role of bone marrow derived stem cells in repair or rejuvenation of tissues and organs, cellular mechanisms of such cell-based therapy remain poorly understood. Methods: We reconstituted hematopoiesis in recipient C57BL/6J mice by transplanting syngeneic GFP+ bone marrow (BM cells. Subsequently, the recipients received subcutaneous injection of granulocyte-colony stimulating factor (G-CSF and were subjected to acute renal ischemic injury. Flow cytometry and immunostaining were performed at various time points to assess engraftment and phenotype of BM derived stem cells. Results: Administration of G-CSF increased the release of BM derived stem cells into circulation and enhanced the ensuing recruitment of BM derived stem cells into injured kidney. During the second month post injury, migrated BM derived stem cells lost hematopoietic phenotype (CD45 but maintained the expression of other markers (Sca-1, CD133 and CD44, suggesting their potential of transdifferentiation into renal stem cells. Moreover, G-CSF treatment enhanced the phenotypic conversion. Conclusion: Our work depicted a time-course dependent transition of phenotypic characteristics of BM derived stem cells, demonstrated the existence of BM derived stem cells in damaged kidney and revealed the effects of G-CSF on cell transdifferentiation.

  17. Intertwining extracellular nucleotides and their receptors with Ca2+ in determining adult neural stem cell survival, proliferation and final fate.

    Science.gov (United States)

    Lecca, Davide; Fumagalli, Marta; Ceruti, Stefania; Abbracchio, Maria P

    2016-08-01

    In the central nervous system (CNS), during both brain and spinal cord development, purinergic and pyrimidinergic signalling molecules (ATP, UTP and adenosine) act synergistically with peptidic growth factors in regulating the synchronized proliferation and final specification of multipotent neural stem cells (NSCs) to neurons, astrocytes or oligodendrocytes, the myelin-forming cells. Some NSCs still persist throughout adulthood in both specific 'neurogenic' areas and in brain and spinal cord parenchyma, retaining the potentiality to generate all the three main types of adult CNS cells. Once CNS anatomical structures are defined, purinergic molecules participate in calcium-dependent neuron-to-glia communication and also control the behaviour of adult NSCs. After development, some purinergic mechanisms are silenced, but can be resumed after injury, suggesting a role for purinergic signalling in regeneration and self-repair also via the reactivation of adult NSCs. In this respect, at least three different types of adult NSCs participate in the response of the adult brain and spinal cord to insults: stem-like cells residing in classical neurogenic niches, in particular, in the ventricular-subventricular zone (V-SVZ), parenchymal oligodendrocyte precursor cells (OPCs, also known as NG2-glia) and parenchymal injury-activated astrocytes (reactive astrocytes). Here, we shall review and discuss the purinergic regulation of these three main adult NSCs, with particular focus on how and to what extent modulation of intracellular calcium levels by purinoceptors is mandatory to determine their survival, proliferation and final fate.This article is part of the themed issue 'Evolution brings Ca(2+) and ATP together to control life and death'. PMID:27377726

  18. Immunological control of adult neural stem cells

    OpenAIRE

    Gonzalez-Perez, Oscar; Quiñones-Hinojosa, Alfredo; Garcia-Verdugo, Jose Manuel

    2010-01-01

    Adult neurogenesis occurs only in discrete regions of adult central nervous system: the subventricular zone and the subgranular zone. These areas are populated by adult neural stem cells (aNSC) that are regulated by a number of molecules and signaling pathways, which control their cell fate choices, survival and proliferation rates. For a long time, it was believed that the immune system did not exert any control on neural proliferative niches. However, it has been observed that many patholog...

  19. Experimental proliferative glomerulonephritis in the cat.

    Science.gov (United States)

    Bishop, S A; Stokes, C R; Lucke, V M

    1992-01-01

    A model of chronic serum sickness was used to induce immune-complex glomerulonephritis in seven experimental cats, by daily intravenous inoculation of an increasing dose (5 to 35 mg) of human serum albumin (HSA). At week four, two of the seven animals developed anterior uveitis. At week 23, two different animals developed the subcutaneous oedema characteristic of the nephrotic syndrome (NS), whilst the other five cats appeared clinically normal. The kidneys were examined at necropsy by light microscopy and by transmission electron microscopy. The glomeruli of four animals (three with both proteinuria and uraemia, and one with proteinuria only) showed morphological changes under light microscopy. The abnormalities suggested that a diffuse mesangial proliferative glomerulonephritis (GN) had been induced in three cats and diffuse membranoproliferative GN induced in another. Ultrastructural studies revealed electron-dense deposits (immune-complexes) in six of the seven cats. Two cats without glomerular abnormalities by light microscopy had mesangial deposits and three cats with mesangial proliferative GN had deposits at mesangial, subendothelial and/or subepithelial sites. The single cat with membranoproliferative GN had deposits at mesangial, subendothelial, subepithelial and intramembranous sites. Immunohistological examination (peroxidase-antiperoxidase technique) showed that HSA and immunoglobulin (IgG and IgM) were deposited in the glomeruli of these cats. Deposits were the most dense in cats with more severe renal lesions. Deposits of IgM were most abundant. An extensive cellular infiltrate, comprising macrophages, neutrophils and plasma cells, was observed only in the four animals which showed abnormalities in glomerular ultrastructure. The disease induced in these cats thus appears to differ from the membranous nephropathy previously described in the cat and bears a close resemblance to immune complex (IC) disease in man. In view of the relatively few specific

  20. IRF4 at the crossroads of effector T-cell fate decision.

    Science.gov (United States)

    Huber, Magdalena; Lohoff, Michael

    2014-07-01

    Interferon regulatory factor 4 (IRF4) is a transcription factor that is expressed in hematopoietic cells and plays pivotal roles in the immune response. Originally described as a lymphocyte-specific nuclear factor, IRF4 promotes differentiation of naïve CD4(+) T cells into T helper 2 (Th2), Th9, Th17, or T follicular helper (Tfh) cells and is required for the function of effector regulatory T (eTreg) cells. Moreover, IRF4 is essential for the sustained differentiation of cytotoxic effector CD8(+) T cells, for CD8(+) T-cell memory formation, and for differentiation of naïve CD8(+) T cells into IL-9-producing (Tc9) and IL-17-producing (Tc17) CD8(+) T-cell subsets. In this review, we focus on recent findings on the role of IRF4 during the development of CD4(+) and CD8(+) T-cell subsets and the impact of IRF4 on T-cell-mediated immune responses in vivo. PMID:24782159

  1. Chromatin dynamics in Pollen Mother Cells underpin a common scenario at the somatic-to-reproductive fate transition of both the male and female lineages in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Wenjing eShe

    2015-04-01

    Full Text Available Unlike animals, where the germline is established early during embryogenesis, plants set aside their reproductive lineage late in development in dedicated floral organs. The specification of pollen mother cells (PMCs committed to meiosis takes place in the sporogenous tissue in anther locules and marks the somatic-to-reproductive cell fate transition towards the male reproductive lineage. Here we show that Arabidopsis PMCs differentiation is accompanied by large-scale changes in chromatin organization. This is characterized by significant increase in nuclear volume, chromatin decondensation, reduction in heterochromatin, eviction of linker histones and the H2AZ histone variant. These structural alterations are accompanied by dramatic, quantitative changes in histone modifications levels compared to that of surrounding somatic cells that do not share a sporogenic fate. All these changes are highly reminiscent of those we have formerly described in female megaspore mother cells (MMCs. This indicates that chromatin reprogramming is a common underlying scenario in the somatic-to-reproductive cell fate transition in both male and female lineages.

  2. Hydrogels with tunable stress relaxation regulate stem cell fate and activity

    Science.gov (United States)

    Chaudhuri, Ovijit; Gu, Luo; Klumpers, Darinka; Darnell, Max; Bencherif, Sidi A.; Weaver, James C.; Huebsch, Nathaniel; Lee, Hong-Pyo; Lippens, Evi; Duda, Georg N.; Mooney, David J.

    2016-03-01

    Natural extracellular matrices (ECMs) are viscoelastic and exhibit stress relaxation. However, hydrogels used as synthetic ECMs for three-dimensional (3D) culture are typically elastic. Here, we report a materials approach to tune the rate of stress relaxation of hydrogels for 3D culture, independently of the hydrogel's initial elastic modulus, degradation, and cell-adhesion-ligand density. We find that cell spreading, proliferation, and osteogenic differentiation of mesenchymal stem cells (MSCs) are all enhanced in cells cultured in gels with faster relaxation. Strikingly, MSCs form a mineralized, collagen-1-rich matrix similar to bone in rapidly relaxing hydrogels with an initial elastic modulus of 17 kPa. We also show that the effects of stress relaxation are mediated by adhesion-ligand binding, actomyosin contractility and mechanical clustering of adhesion ligands. Our findings highlight stress relaxation as a key characteristic of cell-ECM interactions and as an important design parameter of biomaterials for cell culture.

  3. Skeletal Cell Fate Decisions Within Periosteum and Bone Marrow During Bone Regeneration

    OpenAIRE

    Colnot, Céline

    2008-01-01

    Bone repair requires the mobilization of adult skeletal stem cells/progenitors to allow deposition of cartilage and bone at the injury site. These stem cells/progenitors are believed to come from multiple sources including the bone marrow and the periosteum. The goal of this study was to establish the cellular contributions of bone marrow and periosteum to bone healing in vivo and to assess the effect of the tissue environment on cell differentiation within bone marrow and periosteum. Results...

  4. Expression Levels of Histone Deacetylases Determine the Cell Fate of Hematopoietic Progenitors*

    OpenAIRE

    Wada, Taeko; Kikuchi, Jiro; Nishimura, Noriko; Shimizu, Rumi; Kitamura, Toshio; Furukawa, Yusuke

    2009-01-01

    Histone deacetylases (HDACs) are globally implicated in the growth and differentiation of mammalian cells; however, relatively little is known about their specific roles in hematopoiesis. In this study, we investigated the expression of HDACs in human hematopoietic cells and their functions during hematopoiesis. The expression of HDACs was very low in hematopoietic progenitor cells, which was accompanied by histone hyperacetylation. HDACs were detectable in more differentiated progenitors and...

  5. FATE OF EMBRYONIC STEM CELLS TRANSPLANTED INTO THE DEAFENED MAMMALIAN COCHLEA

    OpenAIRE

    Coleman, B.; Hardman, J; Coco, A.; Epp, S; Silva, M; Crook, J; Shepherd, R

    2006-01-01

    Spiral ganglion neurons (SGNs), the primary afferent neurons of the cochlea, degenerate following a sensorineural hearing loss (SNHL) due to lack of trophic support normally received from hair cells. Cell transplantation is emerging as a potential strategy for inner ear rehabilitation, as injected cells may be able to replace damaged SGNs in the deafened cochlea. An increase in the number of surviving SGNs may result in improved efficacy of cochlear implants (CIs). We examined the survival of...

  6. Use of Tritiated Thymidine to Study the Origin and Fate of Inflammatory Cells

    International Nuclear Information System (INIS)

    In a series of experiments mice were injected with tritiated thymidine at various times following a challenging injection of either tetanus or diphtheria toxoid and the number and proportion of mononuclear cells synthesizing DNA at the site of injection determined. It was noted that the increase in mononuclear inflammatory cells was not preceded by a similar decrease in cells synthesizing DNA. This indicates that the majority of inflammatory mononuclear cells must migrate into the inflamed area, presumably from the blood vessels. Inflammatory cells labelled with tritiated thymidine were injected into the site of inflammation, and autopsies performed at various times. Labelled cells were found not only in the inflammatory area, but in the spleen, bone marrow and lymph nodes. These experiments indicate that as the inflammation subsides, inflammatory cells pass back into the lymphatic and blood vascular systems and eventually some find their way to the hemopoietic tissues of the body. Experiments will be reported indicating formation of plasma cells by inflammatory mononuclear cells. These findings will be discussed in relation to hemopoiesis. (author)

  7. Methamphetamine decreases dentate gyrus stem cell self-renewal and shifts the differentiation towards neuronal fate

    OpenAIRE

    Sofia Baptista; Charlène Lasgi; Caroline Benstaali; Nuno Milhazes; Fernanda Borges; Carlos Fontes-Ribeiro; Fabienne Agasse; Ana Paula Silva

    2014-01-01

    Methamphetamine (METH) is a highly addictive psychostimulant drug of abuse that negatively interferes with neurogenesis. In fact, we have previously shown that METH triggers stem/progenitor cell death and decreases neuronal differentiation in the dentate gyrus (DG). Still, little is known regarding its effect on DG stem cell properties. Herein, we investigate the impact of METH on mice DG stem/progenitor cell self-renewal functions. METH (10 nM) decreased DG stem cell self-renewal, while 1 nM...

  8. In vivo MRI of cancer cell fate at the single-cell level in a mouse model of breast cancer metastasis to the brain.

    Science.gov (United States)

    Heyn, Chris; Ronald, John A; Ramadan, Soha S; Snir, Jonatan A; Barry, Andrea M; MacKenzie, Lisa T; Mikulis, David J; Palmieri, Diane; Bronder, Julie L; Steeg, Patricia S; Yoneda, Toshiyuki; MacDonald, Ian C; Chambers, Ann F; Rutt, Brian K; Foster, Paula J

    2006-11-01

    Metastasis (the spread of cancer from a primary tumor to secondary organs) is responsible for most cancer deaths. The ability to follow the fate of a population of tumor cells over time in an experimental animal would provide a powerful new way to monitor the metastatic process. Here we describe a magnetic resonance imaging (MRI) technique that permits the tracking of breast cancer cells in a mouse model of brain metastasis at the single-cell level. Cancer cells that were injected into the left ventricle of the mouse heart and then delivered to the brain were detectable on MR images. This allowed the visualization of the initial delivery and distribution of cells, as well as the growth of tumors from a subset of these cells within the whole intact brain volume. The ability to follow the metastatic process from the single-cell stage through metastatic growth, and to quantify and monitor the presence of solitary undivided cells will facilitate progress in understanding the mechanisms of brain metastasis and tumor dormancy, and the development of therapeutics to treat this disease. PMID:17029229

  9. The B-MYB transcriptional network guides cell cycle progression and fate decisions to sustain self-renewal and the identity of pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Ming Zhan

    Full Text Available Embryonic stem cells (ESCs are pluripotent and have unlimited self-renewal capacity. Although pluripotency and differentiation have been examined extensively, the mechanisms responsible for self-renewal are poorly understood and are believed to involve an unusual cell cycle, epigenetic regulators and pluripotency-promoting transcription factors. Here we show that B-MYB, a cell cycle regulated phosphoprotein and transcription factor critical to the formation of inner cell mass, is central to the transcriptional and co-regulatory networks that sustain normal cell cycle progression and self-renewal properties of ESCs. Phenotypically, B-MYB is robustly expressed in ESCs and induced pluripotent stem cells (iPSCs, and it is present predominantly in a hypo-phosphorylated state. Knockdown of B-MYB results in functional cell cycle abnormalities that involve S, G2 and M phases, and reduced expression of critical cell cycle regulators like ccnb1 and plk1. By conducting gene expression profiling on control and B-MYB deficient cells, ChIP-chip experiments, and integrative computational analyses, we unraveled a highly complex B-MYB-mediated transcriptional network that guides ESC self-renewal. The network encompasses critical regulators of all cell cycle phases and epigenetic regulators, pluripotency transcription factors, and differentiation determinants. B-MYB along with E2F1 and c-MYC preferentially co-regulate cell cycle target genes. B-MYB also co-targets genes regulated by OCT4, SOX2 and NANOG that are significantly associated with stem cell differentiation, embryonic development, and epigenetic control. Moreover, loss of B-MYB leads to a breakdown of the transcriptional hierarchy present in ESCs. These results coupled with functional studies demonstrate that B-MYB not only controls and accelerates cell cycle progression in ESCs it contributes to fate decisions and maintenance of pluripotent stem cell identity.

  10. ZFPIP/Zfp462 is involved in P19 cell pluripotency and in their neuronal fate

    Energy Technology Data Exchange (ETDEWEB)

    Masse, Julie [CNRS UMR 6061, Institut de Genetique et Developpement de Rennes (IGDR), Rennes (France); Universite de Rennes 1, 35043 Rennes cedex (France); Piquet-Pellorce, Claire [Universite de Rennes 1, 35043 Rennes cedex, EA 4427 SeRAIC (France); Viet, Justine; Guerrier, Daniel; Pellerin, Isabelle [CNRS UMR 6061, Institut de Genetique et Developpement de Rennes (IGDR), Rennes (France); Universite de Rennes 1, 35043 Rennes cedex (France); Deschamps, Stephane, E-mail: stephane.deschamps@univ-rennes1.fr [CNRS UMR 6061, Institut de Genetique et Developpement de Rennes (IGDR), Rennes (France); Universite de Rennes 1, 35043 Rennes cedex (France)

    2011-08-01

    The nuclear zinc finger protein ZFPIP/Zfp462 is an important factor involved in cell division during the early embryonic development of vertebrates. In pluripotent P19 cells, ZFPIP/Zfp462 takes part in cell proliferation, likely via its role in maintaining chromatin structure. To further define the function of ZFPIP/Zfp462 in the mechanisms of pluripotency and cell differentiation, we constructed a stable P19 cell line in which ZFPIP/Zfp462 knockdown is inducible. We report that ZFPIP/Zfp462 was vital for mitosis and self-renewal in pluripotent P19 cells. Its depletion induced substantial decreases in the expression of the pluripotency genes Nanog, Oct4 and Sox2 and was associated with the transient expression of specific neuronal differentiation markers. We also demonstrated that ZFPIP/Zfp462 expression appears to be unnecessary after neuronal differentiation is induced in P19 cells. Taken together, our results strongly suggest that ZFPIP/Zfp462 is a key chromatin factor involved in maintaining P19 pluripotency and in the early mechanisms of neural differentiation but that it is dispensable in differentiated P19 cells.

  11. Imaging and fate of stem cells labeled with superparamgnetic nanoparticles in brain and spinal cord injury

    Czech Academy of Sciences Publication Activity Database

    Syková, Eva

    Iowa, 2004. s. 17. [Stem Cell Biology Development and Plasticity A Growth Factor and Signal Transduction Symposium. 16.09.2004-19.09.2004, Iowa] R&D Projects: GA MŠk LN00A065 Keywords : stem cells * nanoparticles Subject RIV: FH - Neurology

  12. ZFPIP/Zfp462 is involved in P19 cell pluripotency and in their neuronal fate

    International Nuclear Information System (INIS)

    The nuclear zinc finger protein ZFPIP/Zfp462 is an important factor involved in cell division during the early embryonic development of vertebrates. In pluripotent P19 cells, ZFPIP/Zfp462 takes part in cell proliferation, likely via its role in maintaining chromatin structure. To further define the function of ZFPIP/Zfp462 in the mechanisms of pluripotency and cell differentiation, we constructed a stable P19 cell line in which ZFPIP/Zfp462 knockdown is inducible. We report that ZFPIP/Zfp462 was vital for mitosis and self-renewal in pluripotent P19 cells. Its depletion induced substantial decreases in the expression of the pluripotency genes Nanog, Oct4 and Sox2 and was associated with the transient expression of specific neuronal differentiation markers. We also demonstrated that ZFPIP/Zfp462 expression appears to be unnecessary after neuronal differentiation is induced in P19 cells. Taken together, our results strongly suggest that ZFPIP/Zfp462 is a key chromatin factor involved in maintaining P19 pluripotency and in the early mechanisms of neural differentiation but that it is dispensable in differentiated P19 cells.

  13. Methamphetamine decreases dentate gyrus stem cell self-renewal and shifts the differentiation towards neuronal fate

    Directory of Open Access Journals (Sweden)

    Sofia Baptista

    2014-09-01

    Full Text Available Methamphetamine (METH is a highly addictive psychostimulant drug of abuse that negatively interferes with neurogenesis. In fact, we have previously shown that METH triggers stem/progenitor cell death and decreases neuronal differentiation in the dentate gyrus (DG. Still, little is known regarding its effect on DG stem cell properties. Herein, we investigate the impact of METH on mice DG stem/progenitor cell self-renewal functions. METH (10 nM decreased DG stem cell self-renewal, while 1 nM delayed cell cycle in the G0/G1-to-S phase transition and increased the number of quiescent cells (G0 phase, which correlated with a decrease in cyclin E, pEGFR and pERK1/2 protein levels. Importantly, both drug concentrations (1 or 10 nM did not induce cell death. In accordance with the impairment of self-renewal capacity, METH (10 nM decreased Sox2+/Sox2+ while increased Sox2−/Sox2− pairs of daughter cells. This effect relied on N-methyl-d-aspartate (NMDA signaling, which was prevented by the NMDA receptor antagonist, MK-801 (10 μM. Moreover, METH (10 nM increased doublecortin (DCX protein levels consistent with neuronal differentiation. In conclusion, METH alters DG stem cell properties by delaying cell cycle and decreasing self-renewal capacities, mechanisms that may contribute to DG neurogenesis impairment followed by cognitive deficits verified in METH consumers.

  14. A subset of osteoblasts expressing high endogenous levels of PPARgamma switches fate to adipocytes in the rat calvaria cell culture model.

    Directory of Open Access Journals (Sweden)

    Yuji Yoshiko

    Full Text Available BACKGROUND: Understanding fate choice and fate switching between the osteoblast lineage (ObL and adipocyte lineage (AdL is important to understand both the developmental inter-relationships between osteoblasts and adipocytes and the impact of changes in fate allocation between the two lineages in normal aging and certain diseases. The goal of this study was to determine when during lineage progression ObL cells are susceptible to an AdL fate switch by activation of endogenous peroxisome proliferator-activated receptor (PPARgamma. METHODOLOGY/PRINCIPAL FINDINGS: Multiple rat calvaria cells within the ObL developmental hierarchy were isolated by either fractionation on the basis of expression of alkaline phosphatase or retrospective identification of single cell-derived colonies, and treated with BRL-49653 (BRL, a synthetic ligand for PPARgamma. About 30% of the total single cell-derived colonies expressed adipogenic potential (defined cytochemically when BRL was present. Profiling of ObL and AdL markers by qRT-PCR on amplified cRNA from over 160 colonies revealed that BRL-dependent adipogenic potential correlated with endogenous PPARgamma mRNA levels. Unexpectedly, a significant subset of relatively mature ObL cells exhibited osteo-adipogenic bipotentiality. Western blotting and immunocytochemistry confirmed that ObL cells co-expressed multiple mesenchymal lineage determinants (runt-related transcription factor 2 (Runx2, PPARgamma, Sox9 and MyoD which localized in the cytoplasm initially, and only Runx2 translocated to the nucleus during ObL progression. Notably, however, some cells exhibited both PPARgamma and Runx2 nuclear labeling with concomitant upregulation of expression of their target genes with BRL treatment. CONCLUSIONS/SIGNIFICANCE: We conclude that not only immature but a subset of relatively mature ObL cells characterized by relatively high levels of endogenous PPARgamma expression can be switched to the AdL. The fact that some Ob

  15. Chinmo is sufficient to induce male fate in somatic cells of the adult Drosophila ovary.

    Science.gov (United States)

    Ma, Qing; de Cuevas, Margaret; Matunis, Erika L

    2016-03-01

    Sexual identity is continuously maintained in specific differentiated cell types long after sex determination occurs during development. In the adult Drosophila testis, the putative transcription factor Chronologically inappropriate morphogenesis (Chinmo) acts with the canonical male sex determinant DoublesexM (Dsx(M)) to maintain the male identity of somatic cyst stem cells and their progeny. Here we find that ectopic expression of chinmo is sufficient to induce a male identity in adult ovarian somatic cells, but it acts through a Dsx(M)-independent mechanism. Conversely, the feminization of the testis somatic stem cell lineage caused by loss of chinmo is enhanced by expression of the canonical female sex determinant Dsx(F), indicating that chinmo acts in parallel with the canonical sex determination pathway to maintain the male identity of testis somatic cells. Consistent with this finding, ectopic expression of female sex determinants in the adult testis disrupts tissue morphology. The miRNA let-7 downregulates chinmo in many contexts, and ectopic expression of let-7 in the adult testis is sufficient to recapitulate the chinmo loss-of-function phenotype, but we find no apparent phenotypes upon removal of let-7 in the adult ovary or testis. Our finding that chinmo is necessary and sufficient to promote a male identity in adult gonadal somatic cells suggests that the sexual identity of somatic cells can be reprogrammed in the adult Drosophila ovary as well as in the testis. PMID:26811385

  16. [Proliferative vitreoretinopathy: pathophysiology and clinical diagnosis].

    Science.gov (United States)

    Rouberol, F; Chiquet, C

    2014-09-01

    Proliferative vitreoretinopathy (PVR) remains one of the most common causes of failed retinal detachment (RD) surgery. Many histological and clinical studies have highlighted the chain of events leading to PVR: cellular migration into the vitreous cavity, cellular differentiation, myofibroblast proliferation and activation, synthesis of extracellular matrix proteins, then contraction of preretinal tissues. The development of PVR can be explained schematically by cellular exposure to growth factors and cytokines (particularly retinal pigment epithelial cells and glial cells), in the context of break-down of the blood-retinal barrier (inflammation, choroidal detachment, iatrogenic effect of cryotherapy and surgery) and of cellular contact with the vitreous. Although the pathophysiology of PVR is now better understood, its severity remains an issue. A systematic search for preoperative PVR risk factors allows the most suitable therapeutic option to be chosen. PMID:24997864

  17. Diverse spatio-temporal dynamical patterns of p53 and cell fate decisions

    Science.gov (United States)

    Clairambault, Jean; Eliaš, Ján

    2016-06-01

    The protein p53 as a tumour suppressor protein accumulates in cells in response to DNA damage and transactivates a large variety of genes involved in apoptosis, cell cycle regulation and numerous other processes. Recent biological observations suggest that specific spatio-temporal dynamical patterns of p53 may be associated with specific cellular response, and thus the spatio-temporal heterogeneity of the p53 dynamics contributes to the overall complexity of p53 signalling. Reaction-diffusion equations taking into account spatial representation of the cell and motion of the species inside the cell can be used to model p53 protein network and could be thus of some help to biologists and pharmacologists in anticancer treatment.

  18. Transcriptional Profiling of Ectoderm Specification to Keratinocyte Fate in Human Embryonic Stem Cells

    OpenAIRE

    Ana Mafalda Baptista Tadeu; Samantha Lin; Lin Hou; Lisa Chung; Mei Zhong; Hongyu Zhao; Valerie Horsley

    2015-01-01

    In recent years, several studies have shed light into the processes that regulate epidermal specification and homeostasis. We previously showed that a broad-spectrum γ-secretase inhibitor DAPT promoted early keratinocyte specification in human embryonic stem cells triggered to undergo ectoderm specification. Here, we show that DAPT accelerates human embryonic stem cell differentiation and induces expression of the ectoderm protein AP2. Furthermore, we utilize RNA sequencing to identify severa...

  19. Cell type dependent morphological adaptation in polyelectrolyte hydrogels governs chondrogenic fate.

    Science.gov (United States)

    Raghothaman, Deepak; Leong, Meng Fatt; Lim, Tze Chiun; Wan, Andrew C A; Ser, Zheng; Lee, Eng Hin; Yang, Zheng

    2016-01-01

    Repair of critical-size articular cartilage defects typically involves delivery of cells in biodegradable, 3D matrices. Differences in the developmental status of mesenchymal stem cells (MSCs) and terminally differentiated mature chondrocytes might be a critical factor in engineering appropriate 3D matrices for articular cartilage tissue engineering. This study examined the relationship between material-driven early cell morphological adaptations and chondrogenic outcomes, by studying the influence of aligned collagen type I (Col I) presentation on chondrocytes and MSC in interfacial polyelectrolyte complexation (IPC)-based hydrogels. In the absence of Col I, both chondrocytes and MSCs adopted rounded cell morphology and formed clusters, with chondrocyte clusters favoring the maintenance of hyaline phenotype, while MSC clusters differentiated to fibro-superficial zone-like chondrocytes. Encapsulated chondrocytes in IPC-Col I hydrogel adopted a fibroblastic morphology forming fibro-superficial zone-like phenotype, which could be reversed by inhibiting actin polymerization using cytochalasin D (CytD). In contrast, adoption of fibroblastic morphology by encapsulated MSCs in IPC-Col I facilitated superior chondrogenesis, generating a mature, hyaline neocartilage tissue. CytD treatment abrogated the elongation of MSCs and brought about a single cell-like state, resulting in insignificant chondrogenic differentiation, underscoring the essential requirement of providing matrix environments that are amenable to cell-cell interactions for robust MSC chondrogenic differentiation. Our study demonstrates that MSCs and culture-expanded chondrocytes favour differential microenvironmental niches and emphasizes the importance of designing biomaterials that meet cell type-specific requirements, in adopting chondrocyte or MSC-based approaches for regenerating hyaline, articular cartilage. PMID:27041648

  20. REX-1 expression and p38 MAPK activation status can determine proliferation/differentiation fates in human mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Dilli Ram Bhandari

    Full Text Available BACKGROUND: REX1/ZFP42 is a well-known embryonic stem cell (ESC marker. However, the role of REX1, itself, is relatively unknown because the function of REX1 has only been reported in the differentiation of ESCs via STAT signaling pathways. Human mesenchymal stem cells (hMSCs isolated from young tissues and cancer cells express REX1. METHODOLOGY/PRINCIPAL FINDING: Human umbilical cord blood-derived MSCs (hUCB-MSCs and adipose tissue-derived MSCs (hAD-MSCs strongly express REX1 and have a lower activation status of p38 MAPK, but bone marrow-derived MSCs (hBM-MSCs have weak REX1 expression and higher activation of p38 MAPK. These results indicated that REX1 expression in hMSCs was positively correlated with proliferation rates but inversely correlated with the phosphorylation of p38 MAPK. In hUCB-MSCs, the roles of REX1 and p38 MAPK were investigated, and a knockdown study was performed using a lentiviral vector-based small hairpin RNA (shRNA. After REX1 knockdown, decreased cell proliferation was observed. In REX1 knocked-down hUCB-MSCs, the osteogenic differentiation ability deteriorated, but the adipogenic potential increased or was similar to that observed in the controls. The phosphorylation of p38 MAPK in hUCB-MSCs significantly increased after REX1 knockdown. After p38 MAPK inhibitor treatment, the cell growth in REX1 knocked-down hUCB-MSCs almost recovered, and the suppressed expression levels of CDK2 and CCND1 were also restored. The expression of MKK3, an upstream regulator of p38 MAPK, significantly increased in REX1 knocked-down hUCB-MSCs. The direct binding of REX1 to the MKK3 gene was confirmed by a chromatin immunoprecipitation (ChIP assay. CONCLUSIONS/SIGNIFICANCE: These findings showed that REX1 regulates the proliferation/differentiation of hMSCs through the suppression of p38 MAPK signaling via the direct suppression of MKK3. Therefore, p38 MAPK and REX-1 status can determine the cell fate of adult stem cells (ASCs. These

  1. Release and fate of fluorocarbons in a shredder residue landfill cell: 2. Field investigations.

    Science.gov (United States)

    Scheutz, Charlotte; Fredenslund, Anders M; Nedenskov, Jonas; Kjeldsen, Peter

    2010-11-01

    The shredder residues from automobiles, home appliances and other metal containing products are often disposed in landfills, as recycling technologies for these materials are not common in many countries. Shredder waste contains rigid and soft foams from cushions and insulation panels blown with fluorocarbons. The objective of this study was to determine the gas composition, attenuation, and emission of fluorocarbons in a monofill shredder residue landfill cell by field investigation. Landfill gas generated within the shredder waste primarily consisted of CH(4) (27%) and N(2) (71%), without CO(2), indicating that the gas composition was governed by chemical reactions in combination with anaerobic microbial reactions. The gas generated also contained different fluorocarbons (up to 27 μg L(-1)). The presence of HCFC-21 and HCFC-31 indicated that anaerobic degradation of CFC-11 occurred in the landfill cell, as neither of these compounds has been produced for industrial applications. This study demonstrates that a landfill cell containing shredder waste has a potential for attenuating CFC-11 released from polyurethane (PUR) insulation foam in the cell via aerobic and anaerobic biodegradation processes. In deeper, anaerobic zones of the cell, reductive dechlorination of CFCs to HCFCs was evident, while in the shallow, oxic zones, there was a high potential for biooxidation of both methane and lesser chlorinated fluorocarbons. These findings correlated well with both laboratory results (presented in a companion paper) and surface emission measurements that, with the exception from a few hot spots, indicated that surface emissions were negative or below detection. PMID:20444588

  2. Optimization of Femtosecond Laser Polymerized Structural Niches to Control Mesenchymal Stromal Cell Fate in Culture

    Directory of Open Access Journals (Sweden)

    Manuela T. Raimondi

    2014-06-01

    Full Text Available We applied two-photon polymerization to fabricate 3D synthetic niches arranged in complex patterns to study the effect of mechano-topological parameters on morphology, renewal and differentiation of rat mesenchymal stromal cells. Niches were formed in a photoresist with low auto-fluorescence, which enabled the clear visualization of the fluorescence emission of the markers used for biological diagnostics within the internal niche structure. The niches were structurally stable in culture up to three weeks. At three weeks of expansion in the niches, cell density increased by almost 10-fold and was 67% greater than in monolayer culture. Evidence of lineage commitment was observed in monolayer culture surrounding the structural niches, and within cell aggregates, but not inside the niches. Thus, structural niches were able not only to direct stem cell homing and colony formation, but also to guide aggregate formation, providing increased surface-to-volume ratios and space for stem cells to adhere and renew, respectively.

  3. Gene dosage imbalance during DNA replication controls bacterial cell-fate decision

    Science.gov (United States)

    Igoshin, Oleg

    Genes encoding proteins in a common regulatory network are frequently located close to one another on the chromosome to facilitate co-regulation or couple gene expression to growth rate. Contrasting with these observations, here we demonstrate a functional role for the arrangement of Bacillus subtilis sporulation network genes on opposite sides of the chromosome. We show that the arrangement of two sporulation network genes, one located close to the origin, the other close to the terminus leads to a transient gene dosage imbalance during chromosome replication. This imbalance is detected by the sporulation network to produce cell-cycle coordinated pulses of the sporulation master regulator Spo0A~P. This pulsed response allows cells to decide between sporulation and continued vegetative growth during each cell-cycle spent in starvation. Furthermore, changes in DNA replication and cell-cycle parameters with decreased growth rate in starvation conditions enable cells to indirectly detect starvation without the need for evaluating specific metabolites. The simplicity of the uncovered coordination mechanism and starvation sensing suggests that it may be widely applicable in a variety of gene regulatory and stress-response settings. This work is supported by National Science Foundation Grants MCB-1244135, EAGER-1450867, MCB-1244423, NIH NIGMS Grant R01 GM088428 and HHMI International Student Fellowship.

  4. The autophagic- lysosomal pathway determines the fate of glial cells under manganese- induced oxidative stress conditions.

    Science.gov (United States)

    Gorojod, R M; Alaimo, A; Porte Alcon, S; Pomilio, C; Saravia, F; Kotler, M L

    2015-10-01

    Manganese (Mn) overexposure is frequently associated with the development of a neurodegenerative disorder known as Manganism. The Mn-mediated generation of reactive oxygen species (ROS) promotes cellular damage, finally leading to apoptotic cell death in rat astrocytoma C6 cells. In this scenario, the autophagic pathway could play an important role in preventing cytotoxicity. In the present study, we found that Mn induced an increase in the amount and total volume of acidic vesicular organelles (AVOs), a process usually related to the activation of the autophagic pathway. Particularly, the generation of enlarged AVOs was a ROS- dependent event. In this report we demonstrated for the first time that Mn induces autophagy in glial cells. This conclusion emerged from the results obtained employing a battery of autophagy markers: a) the increase in LC3-II expression levels, b) the formation of autophagic vesicles labeled with monodansylcadaverine (MDC) or LC3 and, c) the increase in Beclin 1/ Bcl-2 and Beclin 1/ Bcl-X(L) ratio. Autophagy inhibition employing 3-MA and mAtg5(K130R) resulted in decreased cell viability indicating that this event plays a protective role in Mn- induced cell death. In addition, mitophagy was demonstrated by an increase in LC3 and TOM-20 colocalization. On the other hand, we proposed the occurrence of lysosomal membrane permeabilization (LMP) based in the fact that cathepsins B and D activities are essential for cell death. Both cathepsin B inhibitor (Ca-074 Me) or cathepsin D inhibitor (Pepstatin A) completely prevented Mn- induced cytotoxicity. In addition, low dose of Bafilomycin A1 showed a similar effect, a finding that adds evidence about the lysosomal role in Mn cytotoxicity. Finally, in vivo experiments demonstrated that Mn induces injury and alters LC3 expression levels in rat striatal astrocytes. In summary, our results demonstrated that autophagy is activated to counteract the harmful effect caused by Mn. These data is valuable to

  5. Transport across the cell-membrane dictates nanoparticle fate and toxicity: a new paradigm in nanotoxicology

    Science.gov (United States)

    Guarnieri, Daniela; Sabella, Stefania; Muscetti, Ornella; Belli, Valentina; Malvindi, Maria Ada; Fusco, Sabato; de Luca, Elisa; Pompa, Pier Paolo; Netti, Paolo A.

    2014-08-01

    The toxicity of metallic nanoparticles (MNPs) has been fully ascertained, but the mechanisms underlying their cytotoxicity remain still largely unclear. Here we demonstrate that the cytotoxicity of MNPs is strictly reliant on the pathway of cellular internalization. In particular, if otherwise toxic gold, silver, and iron oxide NPs are forced through the cell membrane bypassing any form of active mechanism (e.g., endocytosis), no significant cytotoxic effect is registered. Pneumatically driven NPs across the cell membrane show a different distribution within the cytosol compared to NPs entering the cell by active endocytosis. Specifically, they exhibit free random Brownian motions within the cytosol and do not accumulate in lysosomes. Results suggest that intracellular accumulation of metallic nanoparticles into endo-lysosomal compartments is the leading cause of nanotoxicity, due to consequent nanoparticle degradation and in situ release of metal ions.The toxicity of metallic nanoparticles (MNPs) has been fully ascertained, but the mechanisms underlying their cytotoxicity remain still largely unclear. Here we demonstrate that the cytotoxicity of MNPs is strictly reliant on the pathway of cellular internalization. In particular, if otherwise toxic gold, silver, and iron oxide NPs are forced through the cell membrane bypassing any form of active mechanism (e.g., endocytosis), no significant cytotoxic effect is registered. Pneumatically driven NPs across the cell membrane show a different distribution within the cytosol compared to NPs entering the cell by active endocytosis. Specifically, they exhibit free random Brownian motions within the cytosol and do not accumulate in lysosomes. Results suggest that intracellular accumulation of metallic nanoparticles into endo-lysosomal compartments is the leading cause of nanotoxicity, due to consequent nanoparticle degradation and in situ release of metal ions. Electronic supplementary information (ESI) available. See DOI

  6. SOX17 is a Critical Specifier of Human Primordial Germ Cell Fate

    OpenAIRE

    Irie, Naoko; Weinberger, Leehee; Tang, Walfred W. C.; KOBAYASHI, Toshihiro; Viukov, Sergey; Manor, Yair S.; Dietmann, Sabine; Hanna, Jacob H.; Surani, M. Azim

    2014-01-01

    We thank Rick Livesey and his lab for help with the culture of hESCs; Sohei Kitazawa and Janet Shipley for the TCam-2 cells; Nigel Miller and Andy Riddell for cell sorting, Roger Barker, Xiaoling He, and Pam Tyers for collection of human embryos; and Charles Bradshaw for help with bioinformatics. We thank members of the Surani and Hanna labs for important discussions and technical help. N.I. is supported by Grant-in-Aid for fellows of the JSPS and by BIRAX (the Britain Israe...

  7. Origin and fate of hematopoietic stem precursor cells in the leech Hirudo medicinalis

    Directory of Open Access Journals (Sweden)

    A Grimaldi

    2016-07-01

    Full Text Available The hematopoietic process by which blood cells are formed has been intensely studied for over a century using several model systems. An increasing amount of evidence shows that hematopoiesis, angiogenesis, immune response and the regulating these processes (i.e., cytokines are highly conserved across taxonomic groups. Over the last decade, the leech Hirudo medicinalis, given its simple anatomy and its repertoire of less varied cell types when compared to vertebrates, has been proposed as a powerful model for studying basic steps of hematopoiesis and immune responses. Here, I provide a broad overview of H. medicinalis hematopoiesis and I highlight the benefits of using leech as a model.

  8. Epigenetic Induction of Definitive and Pancreatic Endoderm Cell Fate in Human Fibroblasts

    Science.gov (United States)

    Faas, Marijke M.; de Vos, Paul; Verfaillie, Catherine M.

    2016-01-01

    Reprogramming can occur by the introduction of key transcription factors (TFs) as well as by epigenetic changes. We demonstrated that histone deacetylase inhibitor (HDACi) Trichostatin A (TSA) combined with a chromatin remodeling medium (CRM) induced expression of a number of definitive endoderm and early and late pancreatic marker genes. When CRM was omitted, endoderm/pancreatic marker genes were not induced. Furthermore, treatment with DNA methyltransferase inhibitor (DNMTi) 5-azacytidine (5AZA) CRM did not affect gene expression changes, and when 5AZA was combined with TSA, no further increase in gene expression of endoderm, pancreatic endoderm, and endocrine markers was seen over levels induced with TSA alone. Interestingly, TSA-CRM did not affect expression of pluripotency and hepatocyte genes but induced some mesoderm transcripts. Upon removal of TSA-CRM, the endoderm/pancreatic gene expression profile returned to baseline. Our findings underscore the role epigenetic modification in transdifferentiation of one somatic cell into another. However, full reprogramming of fibroblasts to β-cells will require combination of this approach with TF overexpression and/or culture of the partially reprogrammed cells under β-cell specific conditions. PMID:27403168

  9. Construction of a fucoidan/laminin functional multilayer to direction vascular cell fate and promotion hemocompatibility.

    Science.gov (United States)

    Ye, Changrong; Wang, Yan; Su, Hong; Yang, Ping; Huang, Nan; F Maitz, Manfred; Zhao, Anshan

    2016-07-01

    Surface biofunctional modification of cardiovascular stents is a versatile approach to reduce the adverse effects after implantation. In this work, a novel multifunctional coating was fabricated by coimmobilization of the sulfated polysaccharide of brown algae fucoidan and laminin to biomimic the vascular intimal conditions in order to support rapid endothelialization, prevent restenosis and improve hemocompatibility. The surface properties of the coating such as hydrophilicity, bonding density of biomolecules and stability were evaluated and optimized. According to the biocompatibility tests, the fucoidan/laminin multilayer coated surface displayed less platelet adhesion with favorable anticoagulant property. In addition, the fucoidan/laminin complex showed function to selectively regulate vascular cells growth behavior. The proliferation of endothelial cells (ECs) on the fucoidan/laminin biofunctional coating was significantly promoted. For the smooth muscle cells (SMCs), inhibitory effects on cell adhesion and proliferation were observed. In conclusion, the fucoidan/laminin biofunctional coating was successfully fabricated with desirable anticoagulant and endothelialization properties which show a promising application in the vascular devices such as vascular stents or grafts surface modification. PMID:27127049

  10. Epigenetic Induction of Definitive and Pancreatic Endoderm Cell Fate in Human Fibroblasts.

    Science.gov (United States)

    Sambathkumar, Rangarajan; Kalo, Eric; Van Rossom, Rob; Faas, Marijke M; de Vos, Paul; Verfaillie, Catherine M

    2016-01-01

    Reprogramming can occur by the introduction of key transcription factors (TFs) as well as by epigenetic changes. We demonstrated that histone deacetylase inhibitor (HDACi) Trichostatin A (TSA) combined with a chromatin remodeling medium (CRM) induced expression of a number of definitive endoderm and early and late pancreatic marker genes. When CRM was omitted, endoderm/pancreatic marker genes were not induced. Furthermore, treatment with DNA methyltransferase inhibitor (DNMTi) 5-azacytidine (5AZA) CRM did not affect gene expression changes, and when 5AZA was combined with TSA, no further increase in gene expression of endoderm, pancreatic endoderm, and endocrine markers was seen over levels induced with TSA alone. Interestingly, TSA-CRM did not affect expression of pluripotency and hepatocyte genes but induced some mesoderm transcripts. Upon removal of TSA-CRM, the endoderm/pancreatic gene expression profile returned to baseline. Our findings underscore the role epigenetic modification in transdifferentiation of one somatic cell into another. However, full reprogramming of fibroblasts to β-cells will require combination of this approach with TF overexpression and/or culture of the partially reprogrammed cells under β-cell specific conditions. PMID:27403168

  11. Imaging the fate of implanted stem cells in brain and spinal cord injury

    Czech Academy of Sciences Publication Activity Database

    Syková, Eva

    Innsbruck : organizátor, 2003, s. 1. [FENS Winter School 2003. Kitzbuehel (AT), 07.12.2003-14.12.2003] R&D Projects: GA MŠk LN00A065 Institutional research plan: CEZ:AV0Z5039906 Keywords : Stem cells * spinal cord injury Subject RIV: FH - Neurology

  12. A Progesterone-CXCR4 Axis Controls Mammary Progenitor Cell Fate in the Adult Gland

    Directory of Open Access Journals (Sweden)

    Yu-Jia Shiah

    2015-03-01

    Full Text Available Progesterone drives mammary stem and progenitor cell dynamics through paracrine mechanisms that are currently not well understood. Here, we demonstrate that CXCR4, the receptor for stromal-derived factor 1 (SDF-1; CXC12, is a crucial instructor of hormone-induced mammary stem and progenitor cell function. Progesterone elicits specific changes in the transcriptome of basal and luminal mammary epithelial populations, where CXCL12 and CXCR4 represent a putative ligand-receptor pair. In situ, CXCL12 localizes to progesterone-receptor-positive luminal cells, whereas CXCR4 is induced in both basal and luminal compartments in a progesterone-dependent manner. Pharmacological inhibition of CXCR4 signaling abrogates progesterone-directed expansion of basal (CD24+CD49fhi and luminal (CD24+CD49flo subsets. This is accompanied by a marked reduction in CD49b+SCA-1− luminal progenitors, their functional capacity, and lobuloalveologenesis. These findings uncover CXCL12 and CXCR4 as novel paracrine effectors of hormone signaling in the adult mammary gland, and present a new avenue for potentially targeting progenitor cell growth and malignant transformation in breast cancer.

  13. Equine-Induced Pluripotent Stem Cells Retain Lineage Commitment Toward Myogenic and Chondrogenic Fates

    Directory of Open Access Journals (Sweden)

    Mattia Quattrocelli

    2016-01-01

    Full Text Available Induced pluripotent stem cells (iPSCs hold great potential not only for human but also for veterinary purposes. The equine industry must often deal with health issues concerning muscle and cartilage, where comprehensive regenerative strategies are still missing. In this regard, a still open question is whether equine iPSCs differentiate toward muscle and cartilage, and whether donor cell type influences their differentiation potential. We addressed these questions through an isogenic system of equine iPSCs obtained from myogenic mesoangioblasts (MAB-iPSCs and chondrogenic mesenchymal stem cells (MSC-iPSCs. Despite similar levels of pluripotency characteristics, the myogenic differentiation appeared enhanced in MAB-iPSCs. Conversely, the chondrogenic differentiation was augmented in MSC-iPSCs through both teratoma and in vitro differentiation assays. Thus, our data suggest that equine iPSCs can differentiate toward the myogenic and chondrogenic lineages, and can present a skewed differentiation potential in favor of the source cell lineage.

  14. Genome-wide mapping of Polycomb target genes unravels their roles in cell fate transitions

    DEFF Research Database (Denmark)

    Bracken, Adrian P; Dietrich, Nikolaj; Pasini, Diego;

    2006-01-01

    The Polycomb group (PcG) proteins form chromatin-modifying complexes that are essential for embryonic development and stem cell renewal and are commonly deregulated in cancer. Here, we identify their target genes using genome-wide location analysis in human embryonic fibroblasts. We find that Pol...

  15. Epigenetic Induction of Definitive and Pancreatic Endoderm Cell Fate in Human Fibroblasts

    Directory of Open Access Journals (Sweden)

    Rangarajan Sambathkumar

    2016-01-01

    Full Text Available Reprogramming can occur by the introduction of key transcription factors (TFs as well as by epigenetic changes. We demonstrated that histone deacetylase inhibitor (HDACi Trichostatin A (TSA combined with a chromatin remodeling medium (CRM induced expression of a number of definitive endoderm and early and late pancreatic marker genes. When CRM was omitted, endoderm/pancreatic marker genes were not induced. Furthermore, treatment with DNA methyltransferase inhibitor (DNMTi 5-azacytidine (5AZA CRM did not affect gene expression changes, and when 5AZA was combined with TSA, no further increase in gene expression of endoderm, pancreatic endoderm, and endocrine markers was seen over levels induced with TSA alone. Interestingly, TSA-CRM did not affect expression of pluripotency and hepatocyte genes but induced some mesoderm transcripts. Upon removal of TSA-CRM, the endoderm/pancreatic gene expression profile returned to baseline. Our findings underscore the role epigenetic modification in transdifferentiation of one somatic cell into another. However, full reprogramming of fibroblasts to β-cells will require combination of this approach with TF overexpression and/or culture of the partially reprogrammed cells under β-cell specific conditions.

  16. Proliferative activity of adrenal glands with adrenocortical cytomegaly measured by MIB-1 labeling index.

    Science.gov (United States)

    Fasano, M; Greco, M A

    1996-01-01

    To investigate the proliferative activity of cytomegalic cells in the fetal adrenal cortex, we studied adrenal glands with cytomegaly by immunohistochemistry using the nuclear proliferation maker MIB-1. The percentage of positively stained nuclei was quantified using the SAMBA 4000 image analysis system. Only one case showed occasional positively stained cytomegalic cell nuclei. The permanent cortices showed proliferative activity that decreased with increasing gestational age. No proliferative activity was seen in normal fetal cortices except in one case that received corticosteroid therapy and had a maternal history of diabetes. The near absence of proliferative activity of the cytomegalic cells supports the previously proposed theory of cellular exhaustion following hyperactivity. The high proliferative activity in the fetal cortex of the infant receiving corticosteroid therapy may provide insight into the stimulus causing the hypermetabolic state. PMID:9025875

  17. Heparins for proliferative nephritides? Short review on an advancing topic.

    Science.gov (United States)

    Wardle, E N

    1996-01-01

    The rationale behind a proposed use of heparins for the control of proliferative nephritides is presented. Heparins stop adhesion of leucocytes to endothelial cells, they are anti-complementary, they modulate the activities of phagocytes and they stop the proliferation of mesangial cells or vascular smooth muscle cells. Heparins prevent the release of endothelin-1 and potentiate the action of constitutive nitric oxide. Low-molecular-weight heparins or pentosan polysulphate are now favoured. PMID:8856244

  18. Proliferative verrucous leukoplakia: An update.

    Science.gov (United States)

    Munde, Anita; Karle, Ravindra

    2016-01-01

    Proliferative verrucous leukoplakia (PVL) is a rare form of oral leukoplakia, which was first described in 1985 by Hansen et al. Since then, various published case series have presented PVL as a disease with aggressive biological behavior due to its high probability of recurrence and a high rate of malignant transformation, usually higher than 70%. PVL is a long-term progressive condition, which is observed more frequently in elderly women, over 60 years at the time of diagnosis. The buccal mucosa and tongue are the most frequently involved sites. It develops initially as a white plaque of hyperkeratosis that eventually becomes a multifocal disease with confluent, exophytic and proliferative features with a progressive deterioration of the lesions, making it more and more difficult to control. Tobacco use does not seem to have a significant influence on the appearance or progression of PVL and may occur both in smokers and nonsmokers. Prognosis is poor for this seemingly harmless-appearing white lesion of the oral mucosa. At present, the etiology of PVL remains unclear as well as its management and diagnosis, which is still retrospective, late and poorly defined, lacking consensus criteria. This short review discusses the clinical and histopathological features, diagnosis, traditional treatment and the current management of the disease. PMID:27461595

  19. Prion replication occurs in endogenous adult neural stem cells and alters their neuronal fate: involvement of endogenous neural stem cells in prion diseases.

    Directory of Open Access Journals (Sweden)

    Aroa Relaño-Ginès

    Full Text Available Prion diseases are irreversible progressive neurodegenerative diseases, leading to severe incapacity and death. They are characterized in the brain by prion amyloid deposits, vacuolisation, astrocytosis, neuronal degeneration, and by cognitive, behavioural and physical impairments. There is no treatment for these disorders and stem cell therapy therefore represents an interesting new approach. Gains could not only result from the cell transplantation, but also from the stimulation of endogenous neural stem cells (NSC or by the combination of both approaches. However, the development of such strategies requires a detailed knowledge of the pathology, particularly concerning the status of the adult neurogenesis and endogenous NSC during the development of the disease. During the past decade, several studies have consistently shown that NSC reside in the adult mammalian central nervous system (CNS and that adult neurogenesis occurs throughout the adulthood in the subventricular zone of the lateral ventricle or the Dentate Gyrus of the hippocampus. Adult NSC are believed to constitute a reservoir for neuronal replacement during normal cell turnover or after brain injury. However, the activation of this system does not fully compensate the neuronal loss that occurs during neurodegenerative diseases and could even contribute to the disease progression. We investigated here the status of these cells during the development of prion disorders. We were able to show that NSC accumulate and replicate prions. Importantly, this resulted in the alteration of their neuronal fate which then represents a new pathologic event that might underlie the rapid progression of the disease.

  20. Upon impact: the fate of adhering Pseudomonas fluorescens cells during nanofiltration.

    Science.gov (United States)

    Habimana, Olivier; Semião, Andrea J C; Casey, Eoin

    2014-08-19

    Nanofiltration (NF) is a high-pressure membrane filtration process increasingly applied in drinking water treatment and water reuse processes. NF typically rejects divalent salts, organic matter, and micropollutants. However, the efficiency of NF is adversely affected by membrane biofouling, during which microorganisms adhere to the membrane and proliferate to create a biofilm. Here we show that adhered Pseudomonas fluorescens cells under high permeate flux conditions are met with high fluid shear and convective fluxes at the membrane-liquid interface, resulting in their structural damage and collapse. These results were confirmed by fluorescent staining, flow cytometry, and scanning electron microscopy. This present study offers a "first-glimpse" of cell damage and death during the initial phases of bacterial adhesion to NF membranes and raises a key question about the role of this observed phenomena during early-stage biofilm formation under permeate flux and cross-flow conditions. PMID:25072514

  1. Metabolic reprogramming towards aerobic glycolysis correlates with greater proliferative ability and resistance to metabolic inhibition in CD8 versus CD4 T cells.

    Directory of Open Access Journals (Sweden)

    Yilin Cao

    Full Text Available T lymphocytes (T cells undergo metabolic reprogramming after activation to provide energy and biosynthetic materials for growth, proliferation and differentiation. Distinct T cell subsets, however, adopt metabolic programs specific to support their needs. As CD4 T cells coordinate adaptive immune responses while CD8 T cells become cytotoxic effectors, we compared activation-induced proliferation and metabolic reprogramming of these subsets. Resting CD4 and CD8 T cells were metabolically similar and used a predominantly oxidative metabolism. Following activation CD8 T cells proliferated more rapidly. Stimulation led both CD4 and CD8 T cells to sharply increase glucose metabolism and adopt aerobic glycolysis as a primary metabolic program. Activated CD4 T cells, however, remained more oxidative and had greater maximal respiratory capacity than activated CD8 T cells. CD4 T cells were also associated with greater levels of ROS and increased mitochondrial content, irrespective of the activation context. CD8 cells were better able, however, to oxidize glutamine as an alternative fuel source. The more glycolytic metabolism of activated CD8 T cells correlated with increased capacity for growth and proliferation, along with reduced sensitivity of cell growth to metabolic inhibition. These specific metabolic programs may promote greater growth and proliferation of CD8 T cells and enhance survival in diverse nutrient conditions.

  2. Tracking Cell Fate with Synthetic Memory and Pulse Detecting Transcriptional Circuits

    OpenAIRE

    Inniss, Mara Christine

    2014-01-01

    Synthetic biology aims to engineer biological systems to meet new challenges and teach us more about natural biological systems. These pursuits range from the building of relatively simple transcriptional circuits, to engineering the metabolism of an organism, to reconstructing entire genomes. While we are still emerging from the foundational stages of this new field, we are already using engineered cells to discover underlying biological mechanisms, develop new therapeutics, and produce natu...

  3. rBMP Represses Wnt Signaling and Influences Skeletal Progenitor Cell Fate Specification During Bone Repair

    OpenAIRE

    Minear, Steve; Leucht, Philipp; Miller, Samara; Helms, Jill A.

    2010-01-01

    Bone morphogenetic proteins (BMPs) participate in multiple stages of the fetal skeletogenic program from promoting cell condensation to regulating chondrogenesis and bone formation through endochondral ossification. Here, we show that these pleiotropic functions are recapitulated when recombinant BMPs are used to augment skeletal tissue repair. In addition to their well-documented ability to stimulate chondrogenesis in a skeletal injury, we show that recombinant BMPs (rBMPs) simultaneously su...

  4. Opposing Fgf and Bmp activities regulate the specification of olfactory sensory and respiratory epithelial cell fates

    OpenAIRE

    Maier, Esther; von Hofsten, Jonas; Nord, Hanna; Fernandes, Marie; Paek, Hunki; Hébert, Jean M.; Gunhaga, Lena

    2010-01-01

    The olfactory sensory epithelium and the respiratory epithelium are derived from the olfactory placode. However, the molecular mechanisms regulating the differential specification of the sensory and the respiratory epithelium have remained undefined. To address this issue, we first identified Msx1/2 and Id3 as markers for respiratory epithelial cells by performing quail chick transplantation studies. Next, we established chick explant and intact chick embryo assays of sensory/respiratory epit...

  5. Carbon nanotube-based substrates for modulation of human pluripotent stem cell fate

    OpenAIRE

    Pryzhkova, Marina V; Aria, Indrat; Cheng, Qingsu; Harris, Greg M.; Zan, Xingjie; Gharib, Morteza; Jabbarzadeh, Ehsan

    2014-01-01

    We investigated the biological response of human pluripotent stem cells (hPSCs) cultured on a carbon nanotube (CNT) array-based substrate with the long term goal to direct hPSC germ layer specification for a wide variety of tissue engineering applications. CNT arrays were fabricated using a chemical vapor deposition system allowing for control over surface roughness and mechanical stiffness. Our results demonstrated that hPSCs readily attach to hydrophilized and extracellular matrix coated CN...

  6. Laser ablation of persistent twist cells in Drosophila: muscle precursor fate is not segmentally restricted

    Science.gov (United States)

    Farrell, E. R.; Keshishian, H.

    1999-01-01

    In Drosophila the precursors of the adult musculature arise during embryogenesis. These precursor cells have been termed Persistent Twist Cells (PTCs), as they continue to express the transcription factor Twist after that gene ceases expression elsewhere in the mesoderm. In the larval abdomen, the PTCs are associated with peripheral nerves in stereotypic ventral, dorsal, and lateral clusters, which give rise, respectively, to the ventral, dorsal, and lateral muscle fiber groups of the adult. We tested the developmental potential of the PTCs by using a microbeam laser to ablate specific clusters in larvae. We found that the ablation of a single segmental PTC cluster does not usually result in the deletion of the corresponding adult fibers of that segment. Instead, normal or near normal numbers of adult fibers can form after the ablation. Examination of pupae following ablation showed that migrating PTCs from adjacent segments are able to invade the affected segment, replenishing the ablated cells. However, the ablation of homologous PTCs in multiple segments does result in the deletion of the corresponding adult muscle fibers. These data indicate that the PTCs in an abdominal segment can contribute to the formation of muscle fibers in adjacent abdominal segments, and thus are not inherently restricted to the formation of muscle fibers within their segment of origin.

  7. Study on proliferative responses to host Ia antigens in allogeneic bone marrow chimera in mice: sequential analysis of the reactivity and characterization of the cells involved in the responses

    International Nuclear Information System (INIS)

    Irradiation bone marrow chimeras were established by reconstitution of lethally irradiated AKR mice with C57BL/10 marrow cells to permit serial analysis of the developing reactivities of lymphocytes from such chimeras, [B10----AKR], against donor, host, or third party antigens. We found that substantial proliferative responses to Ia antigens of the recipient strain and also to third party antigens were generated by the thymocytes obtained from the irradiation chimeras at an early stage after bone marrow reconstitution. The majority of the responding thymocytes had surfaces lacking demonstrable peanut agglutinin receptors and were donor type Thy-1+, Ly-2-, and L3T4+ in both anti-recipient and anti-third party MLR. In anti-host responses, however, Ly-2+ thymocytes seemed to be at least partially involved. This capacity of thymus cells to mount a response to antigens of the recipient strain declined shortly thereafter, whereas the capacity to mount MLR against third party antigens persisted. The spleen cells of [B10----AKR] chimeras at the same time developed a more durable capability to exhibit anti-host reactivities and a permanent capability of reacting to third party allo-antigens. The stimulator antigens were Ia molecules on the stimulator cells in both anti-recipient and anti-third party MLR. The responding splenocytes were of donor origin and most of them had Thy-1+, Ly-1+2-, and L3T4+ phenotype

  8. Graded Nodal/Activin signaling titrates conversion of quantitative phospho-Smad2 levels into qualitative embryonic stem cell fate decisions.

    Directory of Open Access Journals (Sweden)

    Kian Leong Lee

    2011-06-01

    Full Text Available Nodal and Activin are morphogens of the TGFbeta superfamily of signaling molecules that direct differential cell fate decisions in a dose- and distance-dependent manner. During early embryonic development the Nodal/Activin pathway is responsible for the specification of mesoderm, endoderm, node, and mesendoderm. In contradiction to this drive towards cellular differentiation, the pathway also plays important roles in the maintenance of self-renewal and pluripotency in embryonic and epiblast stem cells. The molecular basis behind stem cell interpretation of Nodal/Activin signaling gradients and the undertaking of disparate cell fate decisions remains poorly understood. Here, we show that any perturbation of endogenous signaling levels in mouse embryonic stem cells leads to their exit from self-renewal towards divergent differentiation programs. Increasing Nodal signals above basal levels by direct stimulation with Activin promotes differentiation towards the mesendodermal lineages while repression of signaling with the specific Nodal/Activin receptor inhibitor SB431542 induces trophectodermal differentiation. To address how quantitative Nodal/Activin signals are translated qualitatively into distinct cell fates decisions, we performed chromatin immunoprecipitation of phospho-Smad2, the primary downstream transcriptional factor of the Nodal/Activin pathway, followed by massively parallel sequencing, and show that phospho-Smad2 binds to and regulates distinct subsets of target genes in a dose-dependent manner. Crucially, Nodal/Activin signaling directly controls the Oct4 master regulator of pluripotency by graded phospho-Smad2 binding in the promoter region. Hence stem cells interpret and carry out differential Nodal/Activin signaling instructions via a corresponding gradient of Smad2 phosphorylation that selectively titrates self-renewal against alternative differentiation programs by direct regulation of distinct target gene subsets and Oct4

  9. Megaloblastic hematopoiesis in vitro. Interaction of anti-folate receptor antibodies with hematopoietic progenitor cells leads to a proliferative response independent of megaloblastic changes.

    OpenAIRE

    Antony, A C; Briddell, R A; Brandt, J E; Straneva, J E; Verma, R S; M. E. Miller; Kalasinski, L A; R. HOFFMAN

    1991-01-01

    We tested the hypothesis that anti-placental folate receptor (PFR) antiserum-mediated effects on hematopoietic progenitor cells in vitro of increased cell proliferation and megaloblastic morphology were independent responses. We determined that (a) purified IgG from anti-PFR antiserum reacted with purified apo- and holo-PFR and specifically immunoprecipitated a single (44-kD) iodinated moiety on cell surfaces of low density mononuclear cells (LDMNC); (b) when retained in culture during in vit...

  10. Migration, fate and in vivo imaging of adult stem cells in the CNS

    Czech Academy of Sciences Publication Activity Database

    Syková, Eva; Jendelová, Pavla

    2007-01-01

    Roč. 14, - (2007), s. 1336-1342. ISSN 1350-9047 R&D Projects: GA AV ČR KAN201110651; GA MŠk 1M0538; GA MŠk(CZ) LC554; GA ČR(CZ) GA309/06/1594 Grant ostatní: GA MZd(CZ) NR8339; EU(DE) 512146; EU(FR) 518233 Institutional research plan: CEZ:AV0Z50390703 Source of funding: R - rámcový projekt EK ; R - rámcový projekt EK Keywords : Mesenchymal stem cells * Contrast agents * Nanoparticles Subject RIV: FH - Neurology Impact factor: 8.254, year: 2007

  11. The Effect of Pro-Neurogenic Gene Expression on Adult Subventricular Zone Precursor Cell Recruitment and Fate Determination After Excitotoxic Brain Injury

    Science.gov (United States)

    Jones, Kathryn S; Connor, Bronwen J

    2016-01-01

    Despite the presence of on-going neurogenesis in the adult mammalian brain, neurons are generally not replaced after injury. Using a rodent model of excitotoxic cell loss and retroviral (RV) lineage tracing, we previously demonstrated transient recruitment of precursor cells from the subventricular zone (SVZ) into the lesioned striatum. In the current study we determined that these cells included migratory neuroblasts and oligodendrocyte precursor cells (OPC), with the predominant response from glial cells. We attempted to override this glial response by ectopic expression of the pro-neurogenic genes Pax6 or Dlx2 in the adult rat SVZ following quinolinic acid lesioning. RV-Dlx2 over-expression stimulated repair at a previously non-neurogenic time point by enhancing neuroblast recruitment and the percentage of cells that retained a neuronal fate within the lesioned area, compared to RV-GFP controls. RV-Pax6 expression was unsuccessful at inhibiting glial fate and intriguingly, increased OPC cell numbers with no change in neuronal recruitment. These findings suggest that gene choice is important when attempting to augment endogenous repair as the lesioned environment can overcome pro-neurogenic gene expression. Dlx2 over-expression however was able to partially overcome an anti-neuronal environment and therefore is a promising candidate for further study of striatal regeneration.

  12. Wnt-inhibitory factor 1 dysregulation of the bone marrow niche exhausts hematopoietic stem cells

    OpenAIRE

    Schaniel, Christoph; Sirabella, Dario; Qiu, Jiajing; Niu, Xiaohong; Lemischka, Ihor R.; Moore, Kateri A.

    2011-01-01

    The role of Wnt signaling in hematopoietic stem cell fate decisions remains controversial. We elected to dysregulate Wnt signaling from the perspective of the stem cell niche by expressing the pan Wnt inhibitor, Wnt inhibitory factor 1 (Wif1), specifically in osteoblasts. Here we report that osteoblastic Wif1 overexpression disrupts stem cell quiescence, leading to a loss of self-renewal potential. Primitive stem and progenitor populations were more proliferative and elevated in bone marrow a...

  13. Stat3 signaling regulates embryonic stem cell fate in a dose-dependent manner

    Directory of Open Access Journals (Sweden)

    Chih-I Tai

    2014-09-01

    Full Text Available Stat3 is essential for mouse embryonic stem cell (mESC self-renewal mediated by LIF/gp130 receptor signaling. Current understanding of Stat3-mediated ESC self-renewal mechanisms is very limited, and has heretofore been dominated by the view that Stat3 signaling functions in a binary “on/off” manner. Here, in contrast to this binary viewpoint, we demonstrate a contextual, rheostat-like mechanism for Stat3's function in mESCs. Activation and expression levels determine whether Stat3 functions in a self-renewal or a differentiation role in mESCs. We also show that Stat3 induces rapid differentiation of mESCs toward the trophectoderm (TE lineage when its activation level exceeds certain thresholds. Stat3 induces this differentiation phenotype via induction of Tfap2c and its downstream target Cdx2. Our findings provide a novel concept in the realm of Stat3, self-renewal signaling, and pluripotent stem cell biology. Ultimately, this finding may facilitate the development of conditions for the establishment of authentic non-rodent ESCs.

  14. Release and fate of fluorocarbons in a shredder residue landfill cell: 1. Laboratory experiments.

    Science.gov (United States)

    Scheutz, Charlotte; Fredenslund, Anders M; Nedenskov, Jonas; Kjeldsen, Peter

    2010-11-01

    The shredder residues from automobiles, home appliances and other metal-containing products are often disposed in landfills, as recycling technologies for these materials are not common in many countries. Shredder waste contains rigid and soft foams from cushions and insulation panels blown with fluorocarbons. The objective of this study was to use laboratory experiments to estimate fluorocarbon release and attenuation processes in a monofill shredder residue (SR) landfill cell. Waste from the open SR landfill cell at the AV Miljø landfill in Denmark was sampled at three locations. The waste contained 1-3% metal and a relatively low fraction of rigid polyurethane (PUR) foam particles. The PUR waste contained less blowing agent (CFC-11) than predicted from a release model. However, CFC-11 was steadily released in an aerobic bench scale experiment. Anaerobic waste incubation bench tests showed that SRSR produced significant methane (CH(4)), but at rates that were in the low end of the range observed for municipal solid waste. Aerobic and anaerobic batch experiments showed that processes in SRSR potentially can attenuate the fluorocarbons released from the SRSR itself: CFC-11 is degraded under anaerobic conditions with the formation of degradation products, which are being degraded under CH(4) oxidation conditions prevailing in the upper layers of the SR. PMID:20435458

  15. Nuclear receptor NR5A2 controls neural stem cell fate decisions during development

    Science.gov (United States)

    Stergiopoulos, Athanasios; Politis, Panagiotis K.

    2016-01-01

    The enormous complexity of mammalian central nervous system (CNS) is generated by highly synchronized actions of diverse factors and signalling molecules in neural stem/progenitor cells (NSCs). However, the molecular mechanisms that integrate extrinsic and intrinsic signals to control proliferation versus differentiation decisions of NSCs are not well-understood. Here we identify nuclear receptor NR5A2 as a central node in these regulatory networks and key player in neural development. Overexpression and loss-of-function experiments in primary NSCs and mouse embryos suggest that NR5A2 synchronizes cell-cycle exit with induction of neurogenesis and inhibition of astrogliogenesis by direct regulatory effects on Ink4/Arf locus, Prox1, a downstream target of proneural genes, as well as Notch1 and JAK/STAT signalling pathways. Upstream of NR5a2, proneural genes, as well as Notch1 and JAK/STAT pathways control NR5a2 endogenous expression. Collectively, these observations render NR5A2 a critical regulator of neural development and target gene for NSC-based treatments of CNS-related diseases. PMID:27447294

  16. p66Shc Aging Protein in Control of Fibroblasts Cell Fate

    Directory of Open Access Journals (Sweden)

    Mariusz R. Wieckowski

    2011-08-01

    Full Text Available Reactive oxygen species (ROS are wieldy accepted as one of the main factors of the aging process. These highly reactive compounds modify nucleic acids, proteins and lipids and affect the functionality of mitochondria in the first case and ultimately of the cell. Any agent or genetic modification that affects ROS production and detoxification can be expected to influence longevity. On the other hand, genetic manipulations leading to increased longevity can be expected to involve cellular changes that affect ROS metabolism. The 66-kDa isoform of the growth factor adaptor Shc (p66Shc has been recognized as a relevant factor to the oxygen radical theory of aging. The most recent data indicate that p66Shc protein regulates life span in mammals and its phosphorylation on serine 36 is important for the initiation of cell death upon oxidative stress. Moreover, there is strong evidence that apart from aging, p66Shc may be implicated in many oxidative stress-associated pathologies, such as diabetes, mitochondrial and neurodegenerative disorders and tumorigenesis. This article summarizes recent knowledge about the role of p66Shc in aging and senescence and how this protein can influence ROS production and detoxification, focusing on studies performed on skin and skin fibroblasts.

  17. Regulation of Cell Fate Determination by Single-Repeat R3 MYB Transcription Factors in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shucai [Northeast Normal University, Changchun, China; Chen, Jay [ORNL

    2014-01-01

    MYB transcription factors regulate multiple aspects of plant growth and development. Among the large family of MYB transcription factors, single-repeat R3 MYB are characterized by their short sequence (<120 amino acids) consisting largely of the single MYB DNA-binding repeat. In the model plant Arabidopsis, R3 MYBs mediate lateral inhibition during epidermal patterning and are best characterized for their regulatory roles in trichome and root hair development. R3 MYBs act as negative regulators for trichome formation but as positive regulators for root hair development. In this article, we provide a comprehensive review on the role of R3 MYBs in the regulation of cell type specification in the model plant Arabidopsis.

  18. Proliferative and antiproliferative effects of interferon-gamma and tumor necrosis factor-alpha on cell lines derived from cervical and ovarian malignancies

    International Nuclear Information System (INIS)

    Four human cell lines derived from cervical carcinomas (ME-180, SiHa, HT-3, and MS751) and three human cell lines derived from ovarian carcinomas (SK-OV-3, Caov-3, and NIH:OVCAR-3) were analyzed in vitro to determine the effect of recombinant interferon-gamma and recombinant human tumor necrosis factor-alpha on cell growth and survival. The effects of interferon-gamma, tumor necrosis factor-alpha, and both interferon-gamma and tumor necrosis factor-alpha on cell growth were measured after 24 and 72 hours of incubation by the incorporation of chromium 51. The results of this analysis showed that all seven cell lines were resistant to the antiproliferative action of tumor necrosis factor-alpha, that the growth of most cell lines was inhibited by interferon-gamma by 72 hours of incubation, and that after 72 hours of incubation all cell lines demonstrated a synergistic antiproliferative response to the combination of interferon-gamma and tumor necrosis factor-alpha. However, the effects of these cytokines on cell growth were found to differ among cell lines and varied with the concentration and the duration of incubation. The growth of one cell line (Caov-3) was stimulated by both tumor necrosis factor-alpha and interferon-gamma. These results suggest that the clinical effects of these cytokines on the growth of gynecologic cancers may be more complex than previously supposed

  19. Leptin: A proliferative factor for breast cancer?

    International Nuclear Information System (INIS)

    Mammary adipose tissue is an important source of paracrine mitogens and anti-mitogens, including insulin-like growth factor, transforming growth factors, and cytokines (especially, TNFα and IL-1β). Nevertheless, it is also an important source of the adipocytokine, leptin. Recently, leptin was reported to stimulate the proliferation of various cell types (pancreatic β cells, prostate, colorectal, lung, etc.) as a new growth factor. It was also shown to stimulate the proliferation of breast cancer cell lines. In this study, we conducted an immunohistochemical analysis of leptin expression in normal tissue and benign and malignant ductal breast cell, representing the different states of the invasion process. We determined for the first time that leptin is expressed both by ductal breast tumors and by benign lesions as atypical hyperplasia. This suggests that leptin may be taken up or synthesized by all modified ductal breast cells, and may prove a proliferative factor. Moreover, leptin is unexpressed by normal tissue in the healthy breast but is exhibited by the normal tissue in near vicinity of the malignant ductal breast lesions. We also postulated that leptin may be a prognostic or diagnostic factor for ductal breast cancer. These putative hypotheses require further study

  20. Distinctive effects of eicosapentaenoic and docosahexaenoic acids in regulating neural stem cell fate are mediated via endocannabinoid signalling pathways.

    Science.gov (United States)

    Dyall, S C; Mandhair, H K; Fincham, R E A; Kerr, D M; Roche, M; Molina-Holgado, F

    2016-08-01

    Emerging evidence suggests a complex interplay between the endocannabinoid system, omega-3 fatty acids and the immune system in the promotion of brain self-repair. However, it is unknown if all omega-3 fatty acids elicit similar effects on adult neurogenesis and if such effects are mediated or regulated by interactions with the endocannabinoid system. This study investigated the effects of DHA and EPA on neural stem cell (NSC) fate and the role of the endocannabinoid signalling pathways in these effects. EPA, but not DHA, significantly increased proliferation of NSCs compared to controls, an effect associated with enhanced levels of the endocannabinoid 2-arachidonylglycerol (2-AG) and p-p38 MAPK, effects attenuated by pre-treatment with CB1 (AM251) or CB2 (AM630) receptor antagonists. Furthermore, in NSCs derived from IL-1β deficient mice, EPA significantly decreased proliferation and p-p38 MAPK levels compared to controls, suggesting a key role for IL-1β signalling in the effects observed. Although DHA similarly increased 2-AG levels in wild-type NSCs, there was no concomitant increase in proliferation or p-p38 MAPK activity. In addition, in NSCs from IL-1β deficient mice, DHA significantly increased proliferation without effects on p-P38 MAPK, suggesting effects of DHA are mediated via alternative signalling pathways. These results provide crucial new insights into the divergent effects of EPA and DHA in regulating NSC proliferation and the pathways involved, and highlight the therapeutic potential of their interplay with endocannabinoid signalling in brain repair. PMID:27044662

  1. Carbon nanotube-based substrates for modulation of human pluripotent stem cell fate

    Science.gov (United States)

    Pryzhkova, Marina V.; Aria, Indrat; Cheng, Qingsu; Harris, Greg M.; Zan, Xingjie; Gharib, Morteza; Jabbarzadeh, Ehsan

    2016-01-01

    We investigated the biological response of human pluripotent stem cells (hPSCs) cultured on a carbon nanotube (CNT) array-based substrate with the long term goal to direct hPSC germ layer specification for a wide variety of tissue engineering applications. CNT arrays were fabricated using a chemical vapor deposition system allowing for control over surface roughness and mechanical stiffness. Our results demonstrated that hPSCs readily attach to hydrophilized and extracellular matrix coated CNT arrays. hPSCs cultured as colonies in conditions supporting self-renewal demonstrated the morphology and marker expression of undifferentiated hPSCs. Conditions inducing spontaneous differentiation lead to hPSC commitment to all three embryonic germ layers as assessed by immunostaining and RT-PCR analysis. Strikingly, the physical characteristics of CNT arrays favored mesodermal specification of hPSCs. This is contradictory to the behavior of hPSCs on traditional tissue culture plastic which promotes the development of ectoderm. Altogether, these results demonstrate the potential of CNT arrays to be used in the generation of new platforms that allow for precise control of hPSC differentiation by tuning the characteristics of their physical microenvironment. PMID:24690530

  2. Epigenetic control of dendritic cell development and fate determination of common myeloid progenitor by Mysm1.

    Science.gov (United States)

    Won, Haejung; Nandakumar, Vijayalakshmi; Yates, Peter; Sanchez, Suzi; Jones, Lindsey; Huang, Xue F; Chen, Si-Yi

    2014-10-23

    The mechanisms controlling the development of dendritic cells (DCs) remain incompletely understood. Using an Mysm1 knockout (Mysm1(-/-)) mouse model, we identified the histone H2A deubiquitinase Mysm1, as a critical regulator in DC differentiation. Mysm1(-/-) mice showed a global reduction of DCs in lymphoid organs, whereas development of granulocytes and macrophages were not severely affected. Hematopoietic progenitors and DC precursors were significantly decreased in Mysm1(-/-) mice and defective in Fms-like tyrosine kinase-3(Flt3) ligand-induced, but not in granulocyte macrophage-colony-stimulating factor (GM-CSF)-induced DC differentiation in vitro. Molecular studies demonstrated that the developmental defect of DCs from common myeloid progenitor (CMP) in Mysm1(-/-) mice is associated with decreased Flt3 expression and that Mysm1 derepresses transcription of the Flt3 gene by directing histone modifications at the Flt3 promoter region. Two molecular mechanisms were found to be responsible for the selective role of Mysm1 in lineage determination of DCs from CMPs: the selective expression of Mysm1 in a subset of CMPs and the different requirement of Mysm1 for PU.1 recruitment to the Flt3 locus vs GM-CSF-α and macrophage-colony-stimulating factor receptor loci. In conclusion, this study reveals an essential role of Mysm1 in epigenetic regulation of Flt3 transcription and DC development, and it provides a novel mechanism for lineage determination from CMP. PMID:25217698

  3. Carbon nanotube-based substrates for modulation of human pluripotent stem cell fate.

    Science.gov (United States)

    Pryzhkova, Marina V; Aria, Indrat; Cheng, Qingsu; Harris, Greg M; Zan, Xingjie; Gharib, Morteza; Jabbarzadeh, Ehsan

    2014-06-01

    We investigated the biological response of human pluripotent stem cells (hPSCs) cultured on a carbon nanotube (CNT) array-based substrate with the long term goal to direct hPSC germ layer specification for a wide variety of tissue engineering applications. CNT arrays were fabricated using a chemical vapor deposition system allowing for control over surface roughness and mechanical stiffness. Our results demonstrated that hPSCs readily attach to hydrophilized and extracellular matrix coated CNT arrays. hPSCs cultured as colonies in conditions supporting self-renewal demonstrated the morphology and marker expression of undifferentiated hPSCs. Conditions inducing spontaneous differentiation lead to hPSC commitment to all three embryonic germ layers as assessed by immunostaining and RT-PCR analysis. Strikingly, the physical characteristics of CNT arrays favored mesodermal specification of hPSCs. This is contradictory to the behavior of hPSCs on traditional tissue culture plastic which promotes the development of ectoderm. Altogether, these results demonstrate the potential of CNT arrays to be used in the generation of new platforms that allow for precise control of hPSC differentiation by tuning the characteristics of their physical microenvironment. PMID:24690530

  4. Decreased proliferative, migrative and neuro-differentiative potential of postnatal rat enteric neural crest-derived cells during culture in vitro.

    Science.gov (United States)

    Yu, Hui; Pan, Wei-Kang; Zheng, Bai-Jun; Wang, Huai-Jie; Chen, Xin-Lin; Liu, Yong; Gao, Ya

    2016-05-01

    A growing body of evidence supports the potential use of enteric neural crest-derived cells (ENCCs) as a cell replacement therapy for Hirschsprung's disease. Based on previous observations of robust propagation of primary ENCCs, as opposed to their progeny, it is suggested that their therapeutic potential after in vitro expansion may be restricted. We therefore examined the growth and differentiation activities and phenotypic characteristics of continuous ENCC cultures. ENCCs were isolated from the intestines of postnatal rats and were identified using an immunocytochemical approach. During continuous ENCC culture expansion, proliferation, migration, apoptosis, and differentiation potentials were monitored. The Cell Counting Kit-8 was used for assessment of ENCC vitality, Transwell inserts for cell migration, immunocytochemistry for cell counts and identification, and flow cytometry for apoptosis. Over six continuous generations, ENCC proliferation potency was reduced and with prolonged culture, the ratio of migratory ENCCs was decreased. The percentage of apoptosis showed an upward trend with prolonged intragenerational culture, but showed a downward trend with prolonged culture of combined generations. Furthermore, the percentage of peripherin(+) cells decreased whilst the percentage of GFAP(+) cells increased with age. The results demonstrated that alterations in ENCC growth characteristics occur with increased culture time, which may partially account for the poor results of proposed cell therapies. PMID:27068376

  5. Par-3 partitioning defective 3 homolog (C. elegans) and androgen-induced prostate proliferative shutoff associated protein genes are mutationally inactivated in prostate cancer cells

    International Nuclear Information System (INIS)

    Gene identification by nonsense-mediated mRNA decay inhibition (GINI) has proven its usefulness in identifying mutant genes in cancer cell lines. An increase in transcription in response to NMD inhibition of a subset of genes is a major cause of false positives when genes are selected for sequencing analysis. To distinguish between mRNA accumulations caused by stress response-induced transcription and nonsense-containing mRNA stabilizations is a challenge in identifying mutant genes using GINI. To identify potential tumor-suppressor genes mutated in prostate cancer cell lines, we applied a version of GINI that involves inhibition of NMD in two steps. In the first step, NMD is inhibited in duplicate tissue-culture plates. During this step, both the substrate for NMD and stress-response mRNA transcripts are accumulated in cells. In the second step, transcription is inhibited in both plates and NMD is inhibited in one plate and released in the second plate. Microarray analysis of gene-expression profiles in both plates after the second step detects only the differences in mRNA degradation but not in mRNA accumulation. Analyzing gene expression profile alterations in 22RV1 and LNCaP prostate cancer cells following NMD inhibition we selected candidates for sequencing analysis in both cell lines. Sequencing identified inactivating mutations in both alleles of the PARD3 and AS3 genes in the LNCaP and 22RV1 cells, respectively. Introduction of a wild-type PARD3 cDNA into the LNCaP cells resulted in a higher proliferation rate in tissue culture, a higher adhesion of LNCaP cells to the components of extracellular matrix and impaired the growth of the LNCaP cells in soft agar and in a three-dimensional cell-culture. The mutational inactivation in a prostate cancer cell line of the PARD3 gene involved in asymmetric cell division and maintenance of cell-polarity suggests that the loss of cell-polarity contributes to prostate carcinogenesis

  6. Involvement of Numb-mediated HIF-1α inhibition in anti-proliferative effect of PNA-antimiR-182 in trastuzumab-sensitive and -resistant SKBR3 cells.

    Science.gov (United States)

    Sajadimajd, Soraya; Yazdanparast, Razieh; Akram, Sadeghirizi

    2016-04-01

    Trastuzumab is a humanized monoclonal antibody against the human epidermal growth factor receptor 2 (HER2) that is overexpressed in about 25 % of breast cancer patients. However, primary and/or acquired resistance to trastuzumab develops in most affected persons. In this study, we explored the functional role of miR-182 inhibition with aiming the sensitization of SKBR3 cells to trastuzumab. Cell viability, apoptosis, colony formation, and migration capacities of SKBR3(S) (sensitive) and SKBR3(R) (resistant) cells were assessed to determine the anti-proliferative effects of PNA-antimiR-182. In addition, the expression levels of miR-182, mRNA of FOXO1, and Bim as well as the protein levels of HER2 and Notch1 signaling factors were evaluated by stem-loop RT-qPCR, RT-qPCR, and Western blot, respectively. The results indicated that miR-182 might play a causal role in the mechanism of trastuzumab. In line with that, PNA-antimiR-182 inhibited synergistically the viability of both the sensitive and resistant cell groups. Furthermore, the inhibitory effect of PNA-anitmiR-182 on migration in SKBR3 cells was more than the induction of apoptosis. In addition, PNA-antimiR-182 reduced the levels of NICD, Hes1, HIF-1α, and p-Akt in both cell groups, while it augmented the intracellular content of FOXO1 and Numb suppressor proteins. In other words, PNA-antimiR-182-mediated upregulation of Numb was associated with downregulation of HIF-1α and Hes1. Consequently, downregulation of miR-182 might find therapeutical value for overcoming trastuzumab resistance. Graphical Abstract The crosstalk between HER2 and Notch1 signaling pathway is mediated by miR-182. PMID:26563369

  7. Embryonic stem cells are redirected to non-tumorigenic epithelial cell fate by interaction with the mammary microenvironment.

    Directory of Open Access Journals (Sweden)

    Corinne A Boulanger

    Full Text Available Experiments were conducted to redirect mouse Embryonic Stem (ES cells from a tumorigenic phenotype to a normal mammary epithelial phenotype in vivo. Mixing LacZ-labeled ES cells with normal mouse mammary epithelial cells at ratios of 1:5 and 1:50 in phosphate buffered saline and immediately inoculating them into epithelium-divested mammary fat pads of immune-compromised mice accomplished this. Our results indicate that tumorigenesis occurs only when normal mammary ductal growth is not achieved in the inoculated fat pads. When normal mammary gland growth occurs, we find ES cells (LacZ+ progeny interspersed with normal mammary cell progeny in the mammary epithelial structures. We demonstrate that these progeny, marked by LacZ expression, differentiate into multiple epithelial subtypes including steroid receptor positive luminal cells and myoepithelial cells indicating that the ES cells are capable of epithelial multipotency in this context but do not form teratomas. In addition, in secondary transplants, ES cell progeny proliferate, contribute apparently normal mammary progeny, maintain their multipotency and do not produce teratomas.

  8. Anti-proliferative and apoptosis-triggering potential of disulfiram and disulfiram-loaded polysorbate 80-stabilized PLGA nanoparticles on hepatocellular carcinoma Hep3B cell line.

    Science.gov (United States)

    Hoda, Muddasarul; Pajaniradje, Sankar; Shakya, Garima; Mohankumar, Kumaravel; Rajagopalan, Rukkumani

    2016-08-01

    There is an emerging trend to restudy known drugs for their anti-cancer potential. One such anti-alcoholic drug, disulfiram, with significant anti-cancer potential was studied for its efficacy against Hep3B cell lines, an in vitro model of hepatocellular carcinoma. Simultaneously, we intended to study the effect of polysorbate 80-stabilized PLGA nanoparticles and its DSF-loaded counterpart. Cell and nuclear staining, comet assay, flow cytometry and Western blots were performed. Results suggest that cell proliferation was inhibited by DSF and its PLGA nanoparticles through cell cycle arrest, triggering activation of apoptotic pathways that culminates with cell death. DSF loaded nanoparticles when compared with free DSF, showed significantly lesser effect due to its sustained drug-releasing property, while empty nanoparticles showed negligible influence on Hep3B cells. Our results suggest that DSF alone contributes to cell death, while polysorbate 80-stabilized PLGA nanoparticles show sustained drug release patterns that would potentially lower dosage regimens. PMID:27013133

  9. Nuclear shape descriptors by automated morphometry may distinguish aggressive variants of squamous cell carcinoma from relatively benign skin proliferative lesions: a pilot study.

    Science.gov (United States)

    Yang, Weixi; Tian, Rong; Xue, Tongqing

    2015-08-01

    We evaluated whether degrees of dysplasia may be consistently accessed in an automatic fashion, using different kinds of non-melanoma skin cancer (NMSC) as a validatory model. Namely, we compared Bowen disease, actinic keratosis, basal cell carcinoma, low-grade squamous cell carcinoma, and invasive squamous cell carcinoma. We hypothesized that characterizing the shape of nuclei may be important to consistently diagnose the aggressiveness of a skin tumor. While basal cell carcinoma is comparatively relatively benign, management of squamous cell carcinoma is controversial because of its potential to recur and intraoperative dilemma regarding choice of the margin or the depth for the excision. We provide evidence here that progressive nuclear dysplasia may be automatically estimated through the thresholded images of skin cancer and quantitative parameters estimated to provide a quasi-quantitative data, which can thenceforth guide the management of the particular cancer. For circularity, averaging more than 2500 nuclei in each group estimated the means ± SD as 0.8 ± 0.007 vs. 0.78 ± 0.0063 vs. 0.42 ± 0.014 vs. 0.63 ± 0.02 vs. 0.51 ± 0.02 (F = 318063.56, p form, in comparison to locally occurring squamous cell carcinoma and basal cell carcinoma, or benign skin lesions. PMID:25753477

  10. Chmp 1A is a mediator of the anti-proliferative effects of All-trans Retinoic Acid in human pancreatic cancer cells

    Directory of Open Access Journals (Sweden)

    Nguyen Hanh

    2009-02-01

    Full Text Available Abstract Background We recently have shown that Charged multivesicular protein/Chromatin modifying protein1A (Chmp1A functions as a tumor suppressor in human pancreatic tumor cells. Pancreatic cancer has the worst prognosis of all cancers with a dismal 5-year survival rate. Preclinical studies using ATRA for treating human pancreatic cancer suggest this compound might be useful for treatment of pancreatic cancer patients. However, the molecular mechanism by which ATRA inhibits growth of pancreatic cancer cells is not clear. The objective of our study was to investigate whether Chmp1A is involved in ATRA-mediated growth inhibition of human pancreatic tumor cells. Results We performed microarray studies using HEK 293T cells and discovered that Chmp1A positively regulated Cellular retinol-binding protein 1 (CRBP-1. CRBP-1 is a key regulator of All-trans retinoic acid (ATRA through ATRA metabolism and nuclear localization. Since our microarray data indicates a potential involvement of Chmp1A in ATRA signaling, we tested this hypothesis by treating pancreatic tumor cells with ATRA in vitro. In the ATRA-responsive cell lines, ATRA significantly increased the protein expression of Chmp1A, CRBP-1, P53 and phospho-P53 at serine 15 and 37 position. We found that knockdown of Chmp1A via shRNA abolished the ATRA-mediated growth inhibition of PanC-1 cells. Also, Chmp1A silencing diminished the increase of Chmp1A, P53 and phospho-P53 protein expression induced by ATRA. In the ATRA non-responsive cells, ATRA did not have any effect on the protein level of Chmp1A and P53. Chmp1A over-expression, however, induced growth inhibition of ATRA non-responsive cells, which was accompanied by an increase of Chmp1A, P53 and phospho-P53. Interestingly, in ATRA responsive cells Chmp1A is localized to the nucleus, which became robust upon ATRA treatment. In the ATRA-non-responsive cells, Chmp1A was mainly translocated to the plasma membrane upon ATRA treatment. Conclusion

  11. MiR-155 is overexpressed in patients with atopic dermatitis and modulates T-cell proliferative responses by targeting cytotoxic T lymphocyte-associated antigen 4

    DEFF Research Database (Denmark)

    Sonkoly, Enikö; Janson, Peter; Majuri, Marja-Leena; Savinko, Terhi; Fyhrquist, Nanna; Eidsmo, Liv; Xu, Ning; Meisgen, Florian; Wei, Tianling; Bradley, Maria; Stenvang, Jan; Kauppinen, Sakari; Alenius, Harri; Lauerma, Antti; Homey, Bernhard; Winqvist, Ola; Ståhle, Mona; Pivarcsi, Andor

    2010-01-01

    MicroRNAs (miRNAs) are short noncoding RNAs that suppress gene expression at the posttranscriptional level. Atopic dermatitis is a common chronic inflammatory skin disease characterized by the presence of activated T cells within the skin....

  12. Fate of tumor cells injected into left ventricle of heart in BALB/c mice: role of natural killer cells

    DEFF Research Database (Denmark)

    Basse, P; Hokland, P; Heron, I;

    1988-01-01

    arrested and, to a large extent, destroyed in the lungs, which contain the first capillary bed that iv injected tumor cells meet. After LV injection the initial distribution of the tumor cells, which depends on the distribution of cardiac output at the time of injection, was estimated by use of...

  13. Anti-proliferative effects of polyphenols from pomegranate rind (Punica granatum L.) on EJ bladder cancer cells via regulation of p53/miR-34a axis.

    Science.gov (United States)

    Zhou, Benhong; Yi, Huilan; Tan, Jun; Wu, Yue; Liu, Gang; Qiu, Zhenpeng

    2015-03-01

    miRNAs and their validated miRNA targets appear as novel effectors in biological activities of plant polyphenols; however, limited information is available on miR-34a mediated cytotoxicity of pomegranate rind polyphenols in cancer cell lines. For this purpose, cell viability assay, Realtime quantitative PCR for mRNA quantification, western blot for essential protein expression, p53 silencing by shRNA and miR-34a knockdown were performed in the present study. EJ cell treatment with 100 µg (GAE)/mL PRE for 48 h evoked poor cell viability and caspase-dependent pro-apoptosis appearance. PRE also elevated p53 protein and triggered miR-34a expression. The c-Myc and CD44 were confirmed as direct targets of miR-34a in EJ cell apoptosis induced by PRE. Our results provide sufficient evidence that polyphenols in PRE can be potential molecular clusters to suppress bladder cancer cell EJ proliferation via p53/miR-34a axis. PMID:25572695

  14. Anti-Proliferative Effect of Camellianin A in Adinandra nitida Leaves and Its Apoptotic Induction in Human Hep G2 and MCF-7 Cells

    Directory of Open Access Journals (Sweden)

    Han Gao

    2010-05-01

    Full Text Available Leaves of Adinandra nitida constitute a kind of flavonoid-rich plant food. In this study, camellianin A, the main flavonoid in the leaves of Adinandra nitida,was prepared and identified by high performance liquid chromatography-photodiode array detector-electrospray ionization mass spectrometry (HPLC-PDA-ESI/MS. In the anticancer assay, it was found camellianin A could inhibit the proliferation of the human hepatocellular liver carcinoma Hep G2 and human breast adenocarcinoma MCF-7 cell lines in a dose-dependent manner and induce the significant increase of the G0/G1 cell population. After treated by camellianin A, phosphatidylserine of Hep G2 and MCF-7 cells could translocate significantly to the surface of the membrane. The increase of an early apoptotic population of Hep G2 and MCF-7 cells was observed. It was concluded that camellianin A not only affected the progress of the cell cycle, but also induced cells to enter into apoptosis.

  15. Silver Nanoparticles Exhibit the Dose-Dependent Anti-Proliferative Effect against Human Squamous Carcinoma Cells Attenuated in the Presence of Berberine

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    Arkadiusz Dziedzic

    2016-03-01

    Full Text Available The biological activity of nanosize silver particles towards oral epithelium-derived carcinoma seems to be still underinvestigated. We evaluated the influence of low doses of nanosize scale silver particles on the proliferation and viability of malignant oral epithelial keratinocytes in vitro, alone and in conjunction with the plant alkaloid berberine. Cells of human tongue squamous carcinoma SCC-25 (ATCC CRL-1628, cultivated with the mixture of Dulbecco's modified Eagle’s medium, were exposed to silver nanoparticles alone (AgNPs, concentrations from 0.31 to 10 μg/mL and to a combination of AgNPs with berberine chloride (BER, 1/2 IC50 concentration during 24 h and 48 h. The cytotoxic activity of AgNPs with diameters of 10 nm ± 4 nm was measured by 3-(4,5-dimethyl-2-thiazyl-2,5-diphenyl-2H-tetrazolium bromide (MTT assay. Cell cycle analysis was performed by treating cells with propidium iodide followed by flow-activated cell sorting. RT-QPCR reaction was used to assess expression of anti-apoptotic proteins Bcl-2 and pro-apoptotic protein Bcl-2-associated X protein Bax genes expression. Monodisperse silver nanoparticles at a concentration of 10 μg/mL arrested SCC-25 cells cycle after 48 h at the G0/G1 phase in a dose- and time-dependent manner through disruption G0/G1 checkpoint, with increase of Bax/Bcl-2 ratio gene expression. AgNPs exhibit cytotoxic effects on SCC-25 malignant oral epithelial keratinocytes, which is diminished when combined with BER. The AgNPs concentration required to inhibit the growth of carcinoma cells by 50% (IC50 after 48 h was estimated at 5.19 μg/mL. AgNPs combined with BER increased the expression of Bcl-2 while decreasing the ratio of Bax/Bcl-2 in SCC-25 cells. Silver particles at low doses therefore reduce the proliferation and viability of oral squamous cell carcinoma cells. SCC-25 cells are susceptible to damage from AgNPs-induced stress, which can be regulated by the natural alkaloid berberine, suggesting

  16. Anti-proliferative activity of oral anti-hyperglycemic agents on human vascular smooth muscle cells: thiazolidinediones (glitazones have enhanced activity under high glucose conditions

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    de Dios Stephanie T

    2007-10-01

    Full Text Available Abstract Background Inhibition of vascular smooth muscle cell (vSMC proliferation by oral anti-hyperglycemic agents may have a role to play in the amelioration of vascular disease in diabetes. Thiazolidinediones (TZDs inhibit vSMC proliferation but it has been reported that they anomalously stimulate [3H]-thymidine incorporation. We investigated three TZDs, two biguanides and two sulfonylureas for their ability of inhibit vSMC proliferation. People with diabetes obviously have fluctuating blood glucose levels thus we determined the effect of media glucose concentration on the inhibitory activity of TZDs in a vSMC preparation that grew considerably more rapidly under high glucose conditions. We further explored the mechanisms by which TZDs increase [3H]-thymidine incorporation. Methods VSMC proliferation was investigated by [3H]-thymidine incorporation into DNA and cell counting. Activation and inhibition of thymidine kinase utilized short term [3H]-thymidine uptake. Cell cycle events were analyzed by FACS. Results VSMC cells grown for 3 days in DMEM with 5% fetal calf serum under low (5 mM glucose and high (25 mM glucose increased in number by 2.5 and 4.7 fold, respectively. Rosiglitazone and pioglitazone showed modest but statistically significantly greater inhibitory activity under high versus low glucose conditions (P 3H]-thymidine into DNA but did not increase cell numbers. Troglitazone inhibited serum mediated thymidine kinase induction in a concentration dependent manner. FACS analysis showed that troglitazone and rosiglitazone but not pioglitazone placed a slightly higher percentage of cells in the S phase of a growing culture. Of the biguanides, metformin had no effect on proliferation assessed as [3H]-thymidine incorporation or cell numbers whereas phenformin was inhibitory in both assays albeit at high concentrations. The sulfonylureas chlorpropamide and gliclazide had no inhibitory effect on vSMC proliferation assessed by either [3H

  17. In vitro anti-proliferative activities of Aloe perryi flowers extract on human liver, colon, breast, lung, prostate and epithelial cancer cell lines.

    Science.gov (United States)

    Al-Oqail, Mai Mohammad; El-Shaibany, Amina; Al-Jassas, Ebtesam; Al-Sheddi, Ebtesam Saad; Al-Massarani, Shaza Mohamed; Farshori, Nida Nayyar

    2016-03-01

    Natural products, especially plant extracts have offered vast opportunities in the field of drug development due to its chemical diversity. The genus Aloe has for long been used for medicinal purposes in different parts of the world. The present study was designed to investigate the phytochemicals and anti-cancer potential of Aloe perryi flowers. The phytochemical analysis revealed the presence of carbohydrates, glycosides, phytosterols, phenols, flavonoids and proteins. While alkaloids and saponins were absent. The percentage inhibition of various extracts (viz. petroleum ether, chloroform, ethyl acetate, butanol and aqueous) of A. perryi flowers on seven human cancer cell lines (HepG2, HCT-116, MCF-7, A549, PC-3, HEp-2 and HeLa) has been evaluated using MTT assay. All the extracts significantly inhibit the proliferation of cancer cells in a concentration-dependent manner. The petroleum ether extract was most active, where the inhibition was recorded as 92.6%, 93.9%, 92%, 90.9%, 88.9%, 82% and 85.7% for HepG2, HCT-116, MCF-7, A-549, PC-3, HEp-2 and HeLa cells, respectively. The results also revealed that HCT-116 cells were more sensitive among all the cell lines studied. PMID:27113311

  18. Thymic and Postthymic Regulation of Naïve CD4+ T-Cell Lineage Fates in Humans and Mice Models

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    José E. Belizário

    2016-01-01

    Full Text Available Our understanding of how thymocytes differentiate into many subtypes has been increased progressively in its complexity. At early life, the thymus provides a suitable microenvironment with specific combination of stromal cells, growth factors, cytokines, and chemokines to induce the bone marrow lymphoid progenitor T-cell precursors into single-positive CD4+ and CD8+ T effectors and CD4+CD25+ T-regulatory cells (Tregs. At postthymic compartments, the CD4+ T-cells acquire distinct phenotypes which include the classical T-helper 1 (Th1, T-helper 2 (Th2, T-helper 9 (Th9, T-helper 17 (Th17, follicular helper T-cell (Tfh, and induced T-regulatory cells (iTregs, such as the regulatory type 1 cells (Tr1 and transforming growth factor-β- (TGF-β- producing CD4+ T-cells (Th3. Tregs represent only a small fraction, 5–10% in mice and 1-2% in humans, of the overall CD4+ T-cells in lymphoid tissues but are essential for immunoregulatory circuits mediating the inhibition and expansion of all lineages of T-cells. In this paper, we first provide an overview of the major cell-intrinsic developmental programs that regulate T-cell lineage fates in thymus and periphery. Next, we introduce the SV40 immortomouse as a relevant mice model for implementation of new approaches to investigate thymus organogenesis, CD4 and CD8 development, and thymus cells tumorogenesis.

  19. Thymic and Postthymic Regulation of Naïve CD4+ T-Cell Lineage Fates in Humans and Mice Models

    Science.gov (United States)

    Belizário, José E.; Brandão, Wesley; Rossato, Cristiano; Peron, Jean Pierre

    2016-01-01

    Our understanding of how thymocytes differentiate into many subtypes has been increased progressively in its complexity. At early life, the thymus provides a suitable microenvironment with specific combination of stromal cells, growth factors, cytokines, and chemokines to induce the bone marrow lymphoid progenitor T-cell precursors into single-positive CD4+ and CD8+ T effectors and CD4+CD25+ T-regulatory cells (Tregs). At postthymic compartments, the CD4+ T-cells acquire distinct phenotypes which include the classical T-helper 1 (Th1), T-helper 2 (Th2), T-helper 9 (Th9), T-helper 17 (Th17), follicular helper T-cell (Tfh), and induced T-regulatory cells (iTregs), such as the regulatory type 1 cells (Tr1) and transforming growth factor-β- (TGF-β-) producing CD4+ T-cells (Th3). Tregs represent only a small fraction, 5–10% in mice and 1-2% in humans, of the overall CD4+ T-cells in lymphoid tissues but are essential for immunoregulatory circuits mediating the inhibition and expansion of all lineages of T-cells. In this paper, we first provide an overview of the major cell-intrinsic developmental programs that regulate T-cell lineage fates in thymus and periphery. Next, we introduce the SV40 immortomouse as a relevant mice model for implementation of new approaches to investigate thymus organogenesis, CD4 and CD8 development, and thymus cells tumorogenesis.

  20. Planar cell polarity effector gene Intu regulates cell fate-specific differentiation of keratinocytes through the primary cilia

    OpenAIRE

    Dai, D.; Li, L.; Huebner, A; H. Zeng; Guevara, E; Claypool, D J; Liu, A.; Chen, J.

    2012-01-01

    Genes involved in the planar cell polarity (PCP) signaling pathway are essential for a number of developmental processes in mammals, such as convergent extension and ciliogenesis. Tissue-specific PCP effector genes of the PCP signaling pathway are believed to mediate PCP signals in a tissue- and cell type-specific manner. However, how PCP signaling controls the morphogenesis of mammalian tissues remains unclear. In this study, we investigated the role of inturned (Intu), a tissue-specific PCP...

  1. Biogenesis and fate of the cell-cell adhesion molecule, agglutinin, during gametogenesis and fertilization of Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    Fertilization in Chlamydomonas begins with the species-specific recognition and adhesion between gametes of opposite mating types via agglutinin molecules on the flagellar surface. This adhesion generates a cAMP-mediated sexual signal that initiates the subsequent events of call wall release, mating structure activation, and cell fusion. Although flagella of paired gametes remain attached to each other until the zygote forms, the process is dynamic. Engaged agglutinins rapidly become inactivated and turnover, requiring the constant supply of new agglutinins to replace the lost molecules. A population of cell body associated agglutinins has been postulated to the pool of agglutinins recruited during this turnover. Cell body agglutinins, therefore were identified, purified, localized within the cells and compared to flagellar agglutinins. The relationship between these two agglutinin populations was also examined. Cell body agglutinins were biochemically indistinguishable from the flagellar form with respect to their Mr, sedimentation coefficient, and hydrophobicity elution properties. Functionally, however, these molecules were inactive in situ. The calculated surface density of agglutinins in the cell body and flagellar domains was similar and thus could not explain their functional difference, but two domains contiguous and yet distinctive suggested they may be separated by a functional barrier. To test this, a method was developed, using a monoclonal antibody and cycloheximide, that removed the flagellar agglutinins so movement between the domains could be monitored. Mobilization of agglutinins onto the flagella did not occur unless sexual signaling was induced with cAMP and papaverine

  2. New steroidal 17β-carboxy derivatives present anti-5α-reductase activity and anti-proliferative effects in a human androgen-responsive prostate cancer cell line.

    Science.gov (United States)

    Amaral, Cristina; Varela, Carla; Correia-da-Silva, Georgina; Tavares da Silva, Elisiário; Carvalho, Rui A; Costa, Saul C P; Cunha, Sara C; Fernandes, José O; Teixeira, Natércia; Roleira, Fernanda M F

    2013-11-01

    The androgens testosterone (T) and dihydrotestosterone (DHT), besides playing an important role in prostate development and growth, are also responsible for the development and progression of benign prostate hyperplasia (BPH) and prostate cancer. Therefore, the actions of these hormones can be antagonized by preventing the irreversible conversion of T into DHT by inhibiting 5α-reductase (5α-R). This has been a useful therapeutic approach for the referred diseases and can be achieved by using 5α-reductase inhibitors (RIs). Steroidal RIs, finasteride and dutasteride, are used in clinic for BPH treatment and were also proposed for chemoprevention of prostate cancer. Nevertheless, due to the increase in bone and muscle loss, impotency and occurrence of high-grade prostate tumours, it is important to seek for other potent and specific molecules with lower side effects. In the present work, we designed and synthesized steroids with the 3-keto-Δ(4) moiety in the A-ring, as in the 5α-R substrate T, and with carboxamide, carboxyester or carboxylic acid functions at the C-17β position. The inhibitory 5α-R activity, in human prostate microsomes, as well as the anti-proliferative effects of the most potent compounds, in a human androgen-responsive prostate cancer cell line (LNCaP cells), were investigated. Our results showed that steroids 3, 4 and 5 are good RIs, which suggest that C-17β lipophylic amides favour 5α-R inhibition. Moreover, these steroids induce a decrease in cell viability of stimulated LNCaP cells, in a 5α-R dependent-manner, similarly to finasteride. PMID:23933094

  3. Porcine adipose tissue-derived mesenchymal stem cells retain their proliferative characteristics, senescence, karyotype and plasticity after long-term cryopreservation.

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    Rafael Dariolli

    Full Text Available We and others have provided evidence that adipose tissue-derived mesenchymal stem cells (ASCs can mitigate rat cardiac functional deterioration after myocardial ischemia, even though the mechanism of action or the relevance of these findings to human conditions remains elusive. In this regard, the porcine model is a key translational step, because it displays heart anatomic-physiological features that are similar to those found in the human heart. Towards this end, we wanted to establish the cultural characteristics of porcine ASCs (pASCs with or without long-term cryostorage, considering that allogeneic transplantation may also be a future option. Compared to fresh pASCs, thawed cells displayed 90-95% viability and no changes in morphological characteristics or in the expression of surface markers (being pASCs characterized by positive markers CD29(+; CD90(+; CD44(+; CD140b(+; CD105(+; and negative markers CD31(-; CD34(-; CD45(- and SLA-DR(-; n = 3. Mean population doubling time was also comparable (64.26±15.11 hours to thawed cells vs. 62.74±18.07 hours to fresh cells and cumulative population doubling increased constantly until Passage 10 (P10 in the entire cell population, with a small and gradual increase in senescence (P5, 3.25%±0.26 vs. 3.47%±0.32 and P10, 9.6%±0.29 vs. 10.67%±1.25, thawed vs. fresh; SA-β-Gal staining. Chromosomal aberrations were not observed. In addition, under both conditions pASCs responded to adipogenic and osteogenic chemical cues in vitro. In conclusion, we have demonstrated the growth characteristics, senescence, and the capacity of pASCs to respond to chemical cues in vitro and have provided evidence that t