WorldWideScience

Sample records for satellite cell migration

  1. Regulation of turkey myogenic satellite cell migration by MicroRNAs miR-128 and miR-24.

    Science.gov (United States)

    Velleman, S G; Harding, R L

    2016-12-05

    Myogenic satellite cells are an adult stem cell responsible for all post-hatch muscle growth in poultry. As a stem cell population, satellite cells are highly heterogeneous, but the origin of this heterogeneity remains unclear. Heterogeneity is, in part, regulated by gene expression. One method of endogenous gene regulation that may contribute to heterogeneity is microRNAs (miRNAs). Two miRNAs previously shown to regulate poultry myogenic satellite cell proliferation and differentiation, miR-128 and miR-24, were studied to determine if they also affected satellite cell migration. Satellite cell migration is an essential step for both proliferation and differentiation. During proliferation, satellite cells will migrate and align to form new myofibers or donate their nuclei to existing myofibers leading to muscle fiber hypertrophy or regeneration. Transient transfection of miRNA specific mimics to each miRNA reduced migration of satellite cells following a cell culture scratch at 72 h of proliferation when the cultures were 90 to 100% confluent. However, only the migration in cells transfected with miR-24 mimics at 24 and 30 h following the scratch was significantly reduced (P ≤ 0.05) to around 70% of the distance migrated by controls. Alternately, transfection with inhibitors specific to miR-128 or miR-24 significantly (P ≤ 0.05) increased migration between 147 and 252% compared to their controls between 24 and 48 h following the scratch. These data demonstrate that miR-128 and miR-24 play a role in myogenic satellite cell migration, which will impact muscle development and growth.

  2. Satellite And Propeller Migration In Saturn's Rings

    Science.gov (United States)

    Crida, Aurelien; Charnoz, S.; Papaloizou, J.; Salmon, J.

    2009-09-01

    Saturn's rings host satellites like Pan and Daphnis, and smaller bodies like the recently discovered propellers (Tiscareno et al. 2006). These bodies interact gravitationally with the rings. Actually, the resulting perturbations on the ring system have revealed the presence of embedded objects (the Encke and Keeler gaps associated with Pan and Daphnis respectively, the little two-folded structures called propellers tracing the scattering of ring particles by some embedded small objects). Reciprocally, the rings must act on the embedded bodies, leading to their migration. Here, we study how the standard theory of planetary migration applies in Saturn's ring, where the pressure is negligible in contrast with standard protoplanetary disks. Pan and Daphnis should be in standard type II migration, governed by the global disk evolution. Therefore, their presence and position provide constraints on the history of the A-ring, which can be studied using numerical simulations of disk-satellite interactions. The propellers are fully embedded in the disc, and therefore should be subject to type I migration. The simple impulse approximation used by Lin and Papaloi zou (1979) to derive the one-sided torque is particularly suited to this case. Refining their calculation, taking density variations into account, and discussing the possibility for these bodies to enter the type III, runaway regime of migration, we aim at estimating a possible migration rate for these propellers, to be compared to the system life time.

  3. Trafficking and cell migration.

    Science.gov (United States)

    Ulrich, Florian; Heisenberg, Carl-Philipp

    2009-07-01

    The migration of single cells and epithelial sheets is of great importance for gastrulation and organ formation in developing embryos and, if misregulated, can have dire consequences e.g. during cancer metastasis. A keystone of cell migration is the regulation of adhesive contacts, which are dynamically assembled and disassembled via endocytosis. Here, we discuss some of the basic concepts about the function of endocytic trafficking during cell migration: transport of integrins from the cell rear to the leading edge in fibroblasts; confinement of signalling to the front of single cells by endocytic transport of growth factors; regulation of movement coherence in multicellular sheets by cadherin turnover; and shaping of extracellular chemokine gradients. Taken together, endocytosis enables migrating cells and tissues to dynamically modulate their adhesion and signalling, allowing them to efficiently migrate through their extracellular environment.

  4. Tetraspanins in Cell Migration

    Science.gov (United States)

    Jiang, Xupin; Zhang, Jiaping; Huang, Yuesheng

    2015-01-01

    Tetraspanins are a superfamily of small transmembrane proteins that are expressed in almost all eukaryotic cells. Through interacting with one another and with other membrane and intracellular proteins, tetraspanins regulate a wide range of proteins such as integrins, cell surface receptors, and signaling molecules, and thereby engage in diverse cellular processes ranging from cell adhesion and migration to proliferation and differentiation. In particular, tetraspanins modulate the function of proteins involved in all determining factors of cell migration including cell–cell adhesion, cell–ECM adhesion, cytoskeletal protrusion/contraction, and proteolytic ECM remodeling. We herein provide a brief overview of collective in vitro and in vivo studies of tetraspanins to illustrate their regulatory functions in the migration and trafficking of cancer cells, vascular endothelial cells, skin cells (keratinocytes and fibroblasts), and leukocytes. We also discuss the involvement of tetraspanins in various pathologic and remedial processes that rely on cell migration and their potential value as targets for therapeutic intervention. PMID:26091149

  5. Analysing immune cell migration.

    Science.gov (United States)

    Beltman, Joost B; Marée, Athanasius F M; de Boer, Rob J

    2009-11-01

    The visualization of the dynamic behaviour of and interactions between immune cells using time-lapse video microscopy has an important role in modern immunology. To draw robust conclusions, quantification of such cell migration is required. However, imaging experiments are associated with various artefacts that can affect the estimated positions of the immune cells under analysis, which form the basis of any subsequent analysis. Here, we describe potential artefacts that could affect the interpretation of data sets on immune cell migration. We propose how these errors can be recognized and corrected, and suggest ways to prevent the data analysis itself leading to biased results.

  6. Substrate curvature regulates cell migration

    Science.gov (United States)

    He, Xiuxiu; Jiang, Yi

    2017-06-01

    Cell migration is essential in many aspects of biology. Many basic migration processes, including adhesion, membrane protrusion and tension, cytoskeletal polymerization, and contraction, have to act in concert to regulate cell migration. At the same time, substrate topography modulates these processes. In this work, we study how substrate curvature at micrometer scale regulates cell motility. We have developed a 3D mechanical model of single cell migration and simulated migration on curved substrates with different curvatures. The simulation results show that cell migration is more persistent on concave surfaces than on convex surfaces. We have further calculated analytically the cell shape and protrusion force for cells on curved substrates. We have shown that while cells spread out more on convex surfaces than on concave ones, the protrusion force magnitude in the direction of migration is larger on concave surfaces than on convex ones. These results offer a novel biomechanical explanation to substrate curvature regulation of cell migration: geometric constrains bias the direction of the protrusion force and facilitates persistent migration on concave surfaces.

  7. New dimensions in cell migration

    NARCIS (Netherlands)

    Friedl, P.; Sahai, E.; Weiss, S.; Yamada, K.M.

    2012-01-01

    Studies of cell migration in three-dimensional (3D) cell culture systems and in vivo have revealed several differences when compared with cell migration in two dimensions, including their morphology and mechanical and signalling control. Here, researchers assess the contribution of 3D models to our

  8. Thermal migration of water on the Galilean satellites

    Energy Technology Data Exchange (ETDEWEB)

    Purves, N.G.; Pilcher, C.B.

    1980-01-01

    We have modeled the thermal migration of water on the Galilean satellites under the assumption of ballistic molecular trajectories. It is found that water migrating owing to solar radiation on an ice-covered satellite will build up in temperate latitudes, in general not reaching the poles. As much as 50 m of ice may have been lost by this process from the equatorial regions of Europa over the age of the solar system. The disappearance of patches of ice - for instance, the bright rays surrounding some impact craters - from the equatorial regions of Ganymede and Callisto may approach a value (the irreversible evaporation rate) three orders of magnitude larger than the net equatorial loss rate for ice-covered Europa. The presence of water ice pole caps on Ganymede extending to the latitudes at which thermal migration becomes important suggests that some process distributed an extensive, thin covering of water on the satellite, and that the equatorial regions were subsequently cleared by the thermal process.

  9. Cell migration in confined environments.

    Science.gov (United States)

    Irimia, Daniel

    2014-01-01

    We describe a protocol for measuring the speed of human neutrophils migrating through small channels, in conditions of mechanical confinement comparable to those experienced by neutrophils migrating through tissues. In such conditions, we find that neutrophils move persistently, at constant speed for tens of minutes, enabling precise measurements at single cells resolution, for large number of cells. The protocol relies on microfluidic devices with small channels in which a solution of chemoattractant and a suspension of isolated neutrophils are loaded in sequence. The migration of neutrophils can be observed for several hours, starting within minutes after loading the neutrophils in the devices. The protocol is divided into four main steps: the fabrication of the microfluidic devices, the separation of neutrophils from whole blood, the preparation of the assay and cell loading, and the analysis of data. We discuss the practical steps for the implementation of the migration assays in biology labs, the adaptation of the protocols to various cell types, including cancer cells, and the supplementary device features required for precise measurements of directionality and persistence during migration.

  10. A Discrete Cell Migration Model

    Energy Technology Data Exchange (ETDEWEB)

    Nutaro, James J [ORNL; Kruse, Kara L [ORNL; Ward, Richard C [ORNL; O' Quinn, Elizabeth [Wofford College; Woerner, Matthew M [ORNL; Beckerman, Barbara G [ORNL

    2007-01-01

    Migration of vascular smooth muscle cells is a fundamental process in the development of intimal hyperplasia, a precursor to development of cardiovascular disease and a potential response to injury of an arterial wall. Boyden chamber experiments are used to quantify the motion of cell populations in response to a chemoattractant gradient (i.e., cell chemotaxis). We are developing a mathematical model of cell migration within the Boyden chamber, while simultaneously conducting experiments to obtain parameter values for the migration process. In the future, the model and parameters will be used as building blocks for a detailed model of the process that causes intimal hyperplasia. The cell migration model presented in this paper is based on the notion of a cell as a moving sensor that responds to an evolving chemoattractant gradient. We compare the results of our three-dimensional hybrid model with results from a one-dimensional continuum model. Some preliminary experimental data that is being used to refine the model is also presented.

  11. Leucocytes, cytokines and satellite cells

    DEFF Research Database (Denmark)

    Paulsen, Gøran; Mikkelsen, Ulla Ramer; Raastad, Truls

    2012-01-01

    -damaging exercise', primarily eccentric exercise. We review the evidence for the notion that the degree of muscle damage is related to the magnitude of the cytokine response. In the third and final section, we look at the satellite cell response to a single bout of eccentric exercise, as well as the role...... damage. With the exception of IL-6, the sources of systemic cytokines following exercise remain unclear The satellite cell response to severe muscle damage is related to regeneration, whereas the biological significance of satellite cell proliferation after mild damage or non-damaging exercise remains...

  12. Satellite cells: the architects of skeletal muscle.

    Science.gov (United States)

    Chang, Natasha C; Rudnicki, Michael A

    2014-01-01

    The outstanding regenerative capacity of skeletal muscle is attributed to the resident muscle stem cell termed satellite cell. Satellite cells are essential for skeletal muscle regeneration as they ultimately provide the myogenic precursors that rebuild damaged muscle tissue. Satellite cells characteristically are a heterogeneous population of stem cells and committed progenitor cells. Delineation of cellular hierarchy and understanding how lineage fate choices are determined within the satellite cell population will be invaluable for the advancement of muscle regenerative therapies.

  13. Focal Adhesion-Independent Cell Migration.

    Science.gov (United States)

    Paluch, Ewa K; Aspalter, Irene M; Sixt, Michael

    2016-10-06

    Cell migration is central to a multitude of physiological processes, including embryonic development, immune surveillance, and wound healing, and deregulated migration is key to cancer dissemination. Decades of investigations have uncovered many of the molecular and physical mechanisms underlying cell migration. Together with protrusion extension and cell body retraction, adhesion to the substrate via specific focal adhesion points has long been considered an essential step in cell migration. Although this is true for cells moving on two-dimensional substrates, recent studies have demonstrated that focal adhesions are not required for cells moving in three dimensions, in which confinement is sufficient to maintain a cell in contact with its substrate. Here, we review the investigations that have led to challenging the requirement of specific adhesions for migration, discuss the physical mechanisms proposed for cell body translocation during focal adhesion-independent migration, and highlight the remaining open questions for the future.

  14. Migration of Cells in a Social Context

    DEFF Research Database (Denmark)

    Vedel, Søren; Tay, Savas; Johnston, Darius M.

    2013-01-01

    In multicellular organisms and complex ecosystems, cells migrate in a social context. While this is essential for the basic processes of life such as embryonic development, wound healing and unregulated migration furthermore is implicated in diseases such as cancer, the influence of neighboring c...... a test-bed for future studies of collective migration of individual cells.......In multicellular organisms and complex ecosystems, cells migrate in a social context. While this is essential for the basic processes of life such as embryonic development, wound healing and unregulated migration furthermore is implicated in diseases such as cancer, the influence of neighboring...... cells on the individual remains poorly understood. Previous work on isolated cells has revealed a stereotypical migratory behavior, however many aspects of the migration characteristics of cells in populations remained unknown exactly because of this lack of characterization of neighbour-cell influence...

  15. Efficient cell migration requires global chromatin condensation.

    Science.gov (United States)

    Gerlitz, Gabi; Bustin, Michael

    2010-07-01

    Cell migration is a fundamental process that is necessary for the development and survival of multicellular organisms. Here, we show that cell migration is contingent on global condensation of the chromatin fiber. Induction of directed cell migration by the scratch-wound assay leads to decreased DNaseI sensitivity, alterations in the chromatin binding of architectural proteins and elevated levels of H4K20me1, H3K27me3 and methylated DNA. All these global changes are indicative of increased chromatin condensation in response to induction of directed cell migration. Conversely, chromatin decondensation inhibited the rate of cell migration, in a transcription-independent manner. We suggest that global chromatin condensation facilitates nuclear movement and reshaping, which are important for cell migration. Our results support a role for the chromatin fiber that is distinct from its known functions in genetic processes.

  16. Collective cell migration during inflammatory response

    Science.gov (United States)

    Wu, Di; Stroka, Kimberly; Aranda-Espinoza, Helim

    2012-02-01

    Wound scratch healing assays of endothelial cell monolayers is a simple model to study collective cell migration as a function of biological signals. A signal of particular interest is the immune response, which after initial wounding in vivo causes the release of various inflammatory factors such as tumor necrosis alpha (TNF-α). TNF-α is an innate inflammatory cytokine that can induce cell growth, cell necrosis, and change cell morphology. We studied the effects of TNF-α on collective cell migration using the wound healing assays and measured several migration metrics, such as rate of scratch closure, velocities of leading edge and bulk cells, closure index, and velocity correlation functions between migrating cells. We observed that TNF-α alters all migratory metrics as a function of the size of the scratch and TNF-α content. The changes observed in migration correlate with actin reorganization upon TNF-α exposure.

  17. Satellite cells in human skeletal muscle plasticity.

    Science.gov (United States)

    Snijders, Tim; Nederveen, Joshua P; McKay, Bryon R; Joanisse, Sophie; Verdijk, Lex B; van Loon, Luc J C; Parise, Gianni

    2015-01-01

    Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodeling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to humans under physiological conditions. Findings from in vivo human studies suggest that satellite cells play a key role in skeletal muscle fiber repair/remodeling in response to exercise. Mounting evidence indicates that aging has a profound impact on the regulation of satellite cells in human skeletal muscle. Yet, the precise role of satellite cells in the development of muscle fiber atrophy with age remains unresolved. This review seeks to integrate recent results from in vivo human studies on satellite cell function in muscle fiber repair/remodeling in the wider context of satellite cell biology whose literature is largely based on animal and cell models.

  18. Satellite tracking of two Montagu's Harriers (Circus pygargus) : Dual pathways during autumn migration

    NARCIS (Netherlands)

    Trierweiler, Christiane; Koks, Ben J.; Drent, Rudi H.; Exo, Klaus-Michael; Komdeur, Jan; Dijkstra, Cor; Bairlein, Franz

    2007-01-01

    Autumn migration routes of two Dutch female Montagu's Harriers (Circus pygargus) were documented for the first time using satellite telemetry. Both migrated to their African wintering area-one via the Straits of Gibraltar through the Mediterranean and the other via Italy/Tunisia. The rate of travel

  19. Tuning Collective Cell Migration by Cell-Cell Junction Regulation

    NARCIS (Netherlands)

    Friedl, P.; Mayor, R.

    2017-01-01

    Collective cell migration critically depends on cell-cell interactions coupled to a dynamic actin cytoskeleton. Important cell-cell adhesion receptor systems implicated in controlling collective movements include cadherins, immunoglobulin superfamily members (L1CAM, NCAM, ALCAM), Ephrin/Eph receptor

  20. Tuning Collective Cell Migration by Cell-Cell Junction Regulation

    NARCIS (Netherlands)

    Friedl, P.; Mayor, R.

    2017-01-01

    Collective cell migration critically depends on cell-cell interactions coupled to a dynamic actin cytoskeleton. Important cell-cell adhesion receptor systems implicated in controlling collective movements include cadherins, immunoglobulin superfamily members (L1CAM, NCAM, ALCAM), Ephrin/Eph

  1. Human neutrophils facilitate tumor cell transendothelial migration.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

  2. Primordial Germ Cell Specification and Migration.

    Science.gov (United States)

    Marlow, Florence

    2015-01-01

    Primordial germ cells are the progenitor cells that give rise to the gametes. In some animals, the germline is induced by zygotic transcription factors, whereas in others, primordial germ cell specification occurs via inheritance of maternally provided gene products known as germ plasm. Once specified, the primordial germ cells of some animals must acquire motility and migrate to the gonad in order to survive. In all animals examined, perinuclear structures called germ granules form within germ cells. This review focuses on some of the recent studies, conducted by several groups using diverse systems, from invertebrates to vertebrates, which have provided mechanistic insight into the molecular regulation of germ cell specification and migration.

  3. Rho GTPases in collective cell migration

    NARCIS (Netherlands)

    Zegers, M.M.; Friedl, P.

    2014-01-01

    The family of Rho GTPases are intracellular signal transducers that link cell surface signals to multiple intracellular responses. They are best known for their role in regulating actin dynamics required for cell migration, but in addition control cell-cell adhesion, polarization, vesicle traffickin

  4. Rho GTPases in collective cell migration

    NARCIS (Netherlands)

    Zegers, M.M.; Friedl, P.

    2014-01-01

    The family of Rho GTPases are intracellular signal transducers that link cell surface signals to multiple intracellular responses. They are best known for their role in regulating actin dynamics required for cell migration, but in addition control cell-cell adhesion, polarization, vesicle

  5. Emergence of oligarchy in collective cell migration

    Science.gov (United States)

    Schumacher, Linus; Maini, Philip; Baker, Ruth

    Identifying the principles of collective cell migration has the potential to help prevent birth defects, improve regenerative therapies and develop model systems for cancer metastasis. In collaboration with experimental biologists, we use computational simulations of a hybrid model, comprising individual-based stochastic cell movement coupled to a reaction-diffusion equation for a chemoattractant, to explore the role of cell specialisation in the guidance of collective cell migration. In the neural crest, an important migratory cell population in vertebrate embryo development, we present evidence that just a few cells are guiding group migration in a cell-induced chemoattractant gradient that determines the switch between ``leader'' and ``follower'' behaviour in individual cells. This leads us to more generally consider under what conditions cell specialisation might become advantageous for collective migration. Alternatively, individual cell responses to locally different microenvironmental conditions could create the (artefactual) appearance of heterogeneity in a population of otherwise identical cellular agents. We explore these questions using a self-propelled particle model as a minimal description for collective cell migration in two and three dimensions.

  6. Entropy measures of collective cell migration

    Science.gov (United States)

    Whitby, Ariadne; Parrinello, Simona; Faisal, Aldo

    2015-03-01

    Collective cell migration is a critical process during tissue formation and repair. To this end there is a need to develop tools to quantitatively measure the dynamics of collective cell migration obtained from microscopy data. Drawing on statistical physics we use entropy of velocity fields derived from dense optic flow to quantitatively measure collective migration. Using peripheral nerve repair after injury as experimental system, we study how Schwann cells, guided by fibroblasts, migrate in cord-like structures across the cut, paving a highway for neurons. This process of emergence of organised behaviour is key for successful repair, yet the emergence of leader cells and transition from a random to ordered state is not understood. We find fibroblasts induce correlated directionality in migrating Schwann cells as measured by a decrease in the entropy of motion vector. We show our method is robust with respect to image resolution in time and space, giving a principled assessment of how various molecular mechanisms affect macroscopic features of collective cell migration. Finally, the generality of our method allows us to process both simulated cell movement and microscopic data, enabling principled fitting and comparison of in silico to in vitro. ICCS, Imperial College London & MRC Clinical Sciences Centre.

  7. Satellite Cell Heterogeneity in Skeletal Muscle Homeostasis.

    Science.gov (United States)

    Tierney, Matthew T; Sacco, Alessandra

    2016-06-01

    The cellular turnover required for skeletal muscle maintenance and repair is mediated by resident stem cells, also termed satellite cells. Satellite cells normally reside in a quiescent state, intermittently entering the cell cycle to fuse with neighboring myofibers and replenish the stem cell pool. However, the mechanisms by which satellite cells maintain the precise balance between self-renewal and differentiation necessary for long-term homeostasis remain unclear. Recent work has supported a previously unappreciated heterogeneity in the satellite cell compartment that may underlie the observed variability in cell fate and function. In this review, we examine the work supporting this notion as well as the potential governing principles, developmental origins, and principal determinants of satellite cell heterogeneity.

  8. Migration of cells in a social context

    DEFF Research Database (Denmark)

    Vedel, Søren; Tay, Savas; Johnston, Darius M

    2013-01-01

    In multicellular organisms and complex ecosystems, cells migrate in a social context. Whereas this is essential for the basic processes of life, the influence of neighboring cells on the individual remains poorly understood. Previous work on isolated cells has observed a stereotypical migratory b...... and pseudopod collapse following collisions. The model demonstrates how aspects of complex biology can be explained by simple rules of physics and constitutes a rapid test bed for future studies of collective migration of individual cells.......In multicellular organisms and complex ecosystems, cells migrate in a social context. Whereas this is essential for the basic processes of life, the influence of neighboring cells on the individual remains poorly understood. Previous work on isolated cells has observed a stereotypical migratory...

  9. Visualizing T cell migration in-situ

    Directory of Open Access Journals (Sweden)

    Alexandre P Benechet

    2014-07-01

    Full Text Available Mounting a protective immune response is critically dependent on the orchestrated movement of cells within lymphoid tissues. The structure of secondary lymphoid organs regulates immune responses by promoting optimal cell-cell and cell-extracellular matrix interactions. Naïve T cells are initially activated by antigen presenting cells in secondary lymphoid organs. Following priming, effector T cells migrate to the site of infection to exert their functions. Majority of the effector cells die while a small population of antigen specific T cells persist as memory cells in distinct anatomical locations. The persistence and location of memory cells in lymphoid and non-lymphoid tissues is critical to protect the host from re-infection. The localization of memory T cells is carefully regulated by several factors including the highly organized secondary lymphoid structure, the cellular expression of chemokine receptors and compartmentalized secretion of their cognate ligands. This balance between the anatomy and the ordered expression of cell surface and soluble proteins regulates the subtle choreography of T cell migration. In recent years, our understanding of cellular dynamics of T cells has been advanced by the development of new imaging techniques allowing in-situ visualization of T cell responses. Here we review the past and more recent studies that have utilized sophisticated imaging technologies to investigate the migration dynamics of naive, effector and memory T cells.

  10. Chemistry and biology of the compounds that modulate cell migration.

    Science.gov (United States)

    Tashiro, Etsu; Imoto, Masaya

    2016-03-01

    Cell migration is a fundamental step for embryonic development, wound repair, immune responses, and tumor cell invasion and metastasis. Extensive studies have attempted to reveal the molecular mechanisms behind cell migration; however, they remain largely unclear. Bioactive compounds that modulate cell migration show promise as not only extremely powerful tools for studying the mechanisms behind cell migration but also as drug seeds for chemotherapy against tumor metastasis. Therefore, we have screened cell migration inhibitors and analyzed their mechanisms for the inhibition of cell migration. In this mini-review, we introduce our chemical and biological studies of three cell migration inhibitors: moverastin, UTKO1, and BU-4664L.

  11. Erythropoietin, Stem Cell Factor, and Cancer Cell Migration.

    Science.gov (United States)

    Vazquez-Mellado, Maria J; Monjaras-Embriz, Victor; Rocha-Zavaleta, Leticia

    2017-01-01

    Cell migration of normal cells is tightly regulated. However, tumor cells are exposed to a modified microenvironment that promotes cell migration. Invasive migration of tumor cells is stimulated by receptor tyrosine kinases (RTKs) and is regulated by growth factors. Erythropoietin (Epo) is a glycoprotein hormone that regulates erythropoiesis and is also known to be a potent chemotactic agent that induces cell migration by binding to its receptor (EpoR). Expression of EpoR has been documented in tumor cells, and the potential of Epo to induce cell migration has been explored. Stem cell factor (SCF) is a cytokine that synergizes the effects of Epo during erythropoiesis. SCF is the ligand of c-Kit, a member of the RTKs family. Molecular activity of RTKs is a primary stimulus of cell motility. Thus, expression of the SCF/c-Kit axis is associated with cell migration. In this chapter, we summarize data describing the potential effect of Epo/EpoR and SCF/c-Kit as promoters of cancer cell migration. We also integrate recent findings on molecular mechanisms of Epo/EpoR- and SCF/c-Kit-mediated migration described in various cancer models. © 2017 Elsevier Inc. All rights reserved.

  12. PRMT7 Preserves Satellite Cell Regenerative Capacity.

    Science.gov (United States)

    Blanc, Roméo Sébastien; Vogel, Gillian; Chen, Taiping; Crist, Colin; Richard, Stéphane

    2016-02-16

    Regeneration of skeletal muscle requires the continued presence of quiescent muscle stem cells (satellite cells), which become activated in response to injury. Here, we report that whole-body protein arginine methyltransferase PRMT7(-/-) adult mice and mice conditionally lacking PRMT7 in satellite cells using Pax7-CreERT2 both display a significant reduction in satellite cell function, leading to defects in regenerative capacity upon muscle injury. We show that PRMT7 is preferentially expressed in activated satellite cells and, interestingly, PRMT7-deficient satellite cells undergo cell-cycle arrest and premature cellular senescence. These defects underlie poor satellite cell stem cell capacity to regenerate muscle and self-renew after injury. PRMT7-deficient satellite cells express elevated levels of the CDK inhibitor p21CIP1 and low levels of its repressor, DNMT3b. Restoration of DNMT3b in PRMT7-deficient cells rescues PRMT7-mediated senescence. Our findings define PRMT7 as a regulator of the DNMT3b/p21 axis required to maintain muscle stem cell regenerative capacity.

  13. PRMT7 Preserves Satellite Cell Regenerative Capacity

    Directory of Open Access Journals (Sweden)

    Roméo Sébastien Blanc

    2016-02-01

    Full Text Available Regeneration of skeletal muscle requires the continued presence of quiescent muscle stem cells (satellite cells, which become activated in response to injury. Here, we report that whole-body protein arginine methyltransferase PRMT7−/− adult mice and mice conditionally lacking PRMT7 in satellite cells using Pax7-CreERT2 both display a significant reduction in satellite cell function, leading to defects in regenerative capacity upon muscle injury. We show that PRMT7 is preferentially expressed in activated satellite cells and, interestingly, PRMT7-deficient satellite cells undergo cell-cycle arrest and premature cellular senescence. These defects underlie poor satellite cell stem cell capacity to regenerate muscle and self-renew after injury. PRMT7-deficient satellite cells express elevated levels of the CDK inhibitor p21CIP1 and low levels of its repressor, DNMT3b. Restoration of DNMT3b in PRMT7-deficient cells rescues PRMT7-mediated senescence. Our findings define PRMT7 as a regulator of the DNMT3b/p21 axis required to maintain muscle stem cell regenerative capacity.

  14. Satellite Tracking of Post-nesting Migration of Green Turtles

    Institute of Scientific and Technical Information of China (English)

    Wang Wenzhi; Wang Dongxiao; Wang Huajie; Song Xiaojun

    2002-01-01

    @@ During the period August 17-28, 2001, in collaboration with the Provincial Bureau of Oceanography & Fisheries of Guangdong and the South China Institute for Endangered Species, the South China Sea Institute of Oceanology, a CAS affiliate in the city of Guangzhou, conducted a sea turtle satellite tracking project at Haigui Bay (Fig. 1) in the vicinity of Gangkou Town, Huidong County, Guangdong Province.

  15. Regulation of satellite cell function in sarcopenia

    Directory of Open Access Journals (Sweden)

    Stephen E Alway

    2014-09-01

    Full Text Available The mechanisms contributing to sarcopenia include reduced satellite cell (myogenic stem cell function that is impacted by the environment (niche of these cells. Satellite cell function is affected by oxidative stress, which is elevated in aged muscles, and this along with changes in largely unknown systemic factors, likely contribute to the manner in which satellite cells respond to stressors such as exercise, disuse or rehabilitation in sarcopenic muscles. Nutritional intervention provides one therapeutic strategy to improve the satellite cell niche and systemic factors, with the goal of improving satellite cell function in aging muscles. Although many elderly persons consume various nutraceuticals with the hope of improving health, most of these compounds have not been thoroughly tested, and the impacts that they might have on sarcopenia, and satellite cell function are not clear. This review discusses data pertaining to the satellite cell responses and function in aging skeletal muscle, and the impact that three compounds: resveratrol, green tea catechins and β-Hydroxy-β-methylbutyrate have on regulating satellite cell function and therefore contributing to reducing sarcopenia or improving muscle mass after disuse in aging. The data suggest that these nutraceutical compounds improve satellite cell function during rehabilitative loading in animal models of aging after disuse (i.e., muscle regeneration. While these compounds have not been rigorously tested in humans, the data from animal models of aging provide a strong basis for conducting additional focused work to determine if these or other nutraceuticals can offset the muscle losses, or improve regeneration in sarcopenic muscles of older humans via improving satellite cell function.

  16. Study of cell migration in microfabricated channels.

    Science.gov (United States)

    Vargas, Pablo; Terriac, Emmanuel; Lennon-Duménil, Ana-Maria; Piel, Matthieu

    2014-02-21

    The method described here allows the study of cell migration under confinement in one dimension. It is based on the use of microfabricated channels, which impose a polarized phenotype to cells by physical constraints. Once inside channels, cells have only two possibilities: move forward or backward. This simplified migration in which directionality is restricted facilitates the automatic tracking of cells and the extraction of quantitative parameters to describe cell movement. These parameters include cell velocity, changes in direction, and pauses during motion. Microchannels are also compatible with the use of fluorescent markers and are therefore suitable to study localization of intracellular organelles and structures during cell migration at high resolution. Finally, the surface of the channels can be functionalized with different substrates, allowing the control of the adhesive properties of the channels or the study of haptotaxis. In summary, the system here described is intended to analyze the migration of large cell numbers in conditions in which both the geometry and the biochemical nature of the environment are controlled, facilitating the normalization and reproducibility of independent experiments.

  17. Study of Cell Migration in Microfabricated Channels

    Science.gov (United States)

    Vargas, Pablo; Terriac, Emmanuel; Lennon-Duménil, Ana-Maria; Piel, Matthieu

    2014-01-01

    The method described here allows the study of cell migration under confinement in one dimension. It is based on the use of microfabricated channels, which impose a polarized phenotype to cells by physical constraints. Once inside channels, cells have only two possibilities: move forward or backward. This simplified migration in which directionality is restricted facilitates the automatic tracking of cells and the extraction of quantitative parameters to describe cell movement. These parameters include cell velocity, changes in direction, and pauses during motion. Microchannels are also compatible with the use of fluorescent markers and are therefore suitable to study localization of intracellular organelles and structures during cell migration at high resolution. Finally, the surface of the channels can be functionalized with different substrates, allowing the control of the adhesive properties of the channels or the study of haptotaxis. In summary, the system here described is intended to analyze the migration of large cell numbers in conditions in which both the geometry and the biochemical nature of the environment are controlled, facilitating the normalization and reproducibility of independent experiments. PMID:24637569

  18. Evidence that dorsally mounted satellite transmitters affect migration chronology of Northern Pintails

    Science.gov (United States)

    Hupp, Jerry; Kharitonov, Sergei; Yamaguchi, Noriyuki M.; Ozaki, K.; Flint, Paul L.; Pearce, John M.; Tokita, Ken-ichi; Shimada, Tetsuo; Higuchi, Hiroyoshi

    2015-01-01

    We compared migration movements and chronology between Northern Pintails (Anas acuta) marked with dorsally mounted satellite transmitters and pintails marked only with tarsus rings. During weekly intervals of spring and autumn migration between their wintering area in Japan and nesting areas in Russia, the mean distance that ringed pintails had migrated was up to 1000 km farther than the mean distance radiomarked pintails migrated. Radiomarked pintails were detected at spring migration sites on average 9.9 days (90 % CI 8.0, 11.8) later than ringed pintails that were recovered within 50 km. Although ringed and radiomarked pintails departed from Japan on similar dates, the disparity in detection of radiomarked versus ringed pintails at shared sites increased 7.7 days (90 % CI 5.2, 10.2) for each 1000 km increase in distance from Japan. Thus, pintails marked with satellite transmitters arrived at nesting areas that were 2500 km from Japan on average 19 days later than ringed birds. Radiomarked pintails were detected at autumn migration stopovers on average 13.1 days (90 % CI 9.8, 16.4) later than ringed birds that were recovered within 50 km. We hypothesize that dorsal attachment of 12–20 g satellite transmitters to Northern Pintails increased the energetic cost of flight, which resulted in more rapid depletion of energetic reserves and shortened the distance pintails could fly without refueling. Radiomarked pintails may have used more stopovers or spent longer periods at stopovers. causing their migration schedule to diverge from ringed pintails. We urge further evaluation of the effects of dorsally mounted transmitters on migration chronology of waterfowl.

  19. China's First Satellite Tracking of Migration Route of Black-necked Cranes

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Teaming up with colleagues at home and abroad, CAS scientists launched China's first ever satellite tracking project on Black-necked Cranes in late February at the National Dashanbao Black-necked Crane Natural Reserve in southwest China's Yunnan Province. Its objective is to understand the migration route of the crane's eastern population so as to better protect this rare species.

  20. Collective cell migration: a mechanistic perspective.

    Science.gov (United States)

    Vedula, Sri Ram Krishna; Ravasio, Andrea; Lim, Chwee Teck; Ladoux, Benoit

    2013-11-01

    Collective cell migration is fundamental to gaining insights into various important biological processes such as wound healing and cancer metastasis. In particular, recent in vitro studies and in silico simulations suggest that mechanics can explain the social behavior of multicellular clusters to a large extent with minimal knowledge of various cellular signaling pathways. These results suggest that a mechanistic perspective is necessary for a comprehensive and holistic understanding of collective cell migration, and this review aims to provide a broad overview of such a perspective.

  1. Engineered Models of Confined Cell Migration

    Science.gov (United States)

    Paul, Colin D.; Hung, Wei-Chien; Wirtz, Denis; Konstantopoulos, Konstantinos

    2017-01-01

    Cells in the body are physically confined by neighboring cells, tissues, and the extracellular matrix. Although physical confinement modulates intracellular signaling and the underlying mechanisms of cell migration, it is difficult to study in vivo. Furthermore, traditional two-dimensional cell migration assays do not recapitulate the complex topographies found in the body. Therefore, a number of experimental in vitro models that confine and impose forces on cells in well-defined microenvironments have been engineered. We describe the design and use of microfluidic microchannel devices, grooved substrates, micropatterned lines, vertical confinement devices, patterned hydrogels, and micropipette aspiration assays for studying cell responses to confinement. Use of these devices has enabled the delineation of changes in cytoskeletal reorganization, cell–substrate adhesions, intracellular signaling, nuclear shape, and gene expression that result from physical confinement. These assays and the physiologically relevant signaling pathways that have been elucidated are beginning to have a translational and clinical impact. PMID:27420571

  2. Primordial Germ Cell Specification and Migration

    Science.gov (United States)

    Marlow, Florence

    2015-01-01

    Primordial germ cells are the progenitor cells that give rise to the gametes. In some animals, the germline is induced by zygotic transcription factors, whereas in others, primordial germ cell specification occurs via inheritance of maternally provided gene products known as germ plasm. Once specified, the primordial germ cells of some animals must acquire motility and migrate to the gonad in order to survive. In all animals examined, perinuclear structures called germ granules form within germ cells. This review focuses on some of the recent studies, conducted by several groups using diverse systems, from invertebrates to vertebrates, which have provided mechanistic insight into the molecular regulation of germ cell specification and migration. PMID:26918157

  3. Plasticity of cell migration: a multiscale tuning model.

    NARCIS (Netherlands)

    Friedl, P.H.A.; Wolf, K. van der

    2010-01-01

    Cell migration underlies tissue formation, maintenance, and regeneration as well as pathological conditions such as cancer invasion. Structural and molecular determinants of both tissue environment and cell behavior define whether cells migrate individually (through amoeboid or mesenchymal modes) or

  4. Plasticity of cell migration: a multiscale tuning model.

    NARCIS (Netherlands)

    Friedl, P.H.A.; Wolf, K. van der

    2010-01-01

    Cell migration underlies tissue formation, maintenance, and regeneration as well as pathological conditions such as cancer invasion. Structural and molecular determinants of both tissue environment and cell behavior define whether cells migrate individually (through amoeboid or mesenchymal modes) or

  5. Modeling traction forces in collective cell migration

    Science.gov (United States)

    Zimmermann, Juliane; Basan, Markus; Hayes, Ryan L.; Rappel, Wouter-Jan; Levine, Herbert

    2015-03-01

    Collective cell migration is an important process in embryonic development, wound healing, and cancer metastasis. We have developed a particle-based simulation for collective cell migration that describes flow patterns and finger formation at the tissue edge observed in wound healing experiments. We can apply methods for calculating intercellular stress to our simulation model, and have thereby provided evidence for the validity of a stress reconstitution method from traction forces used in experiments. To accurately capture experimentally measured traction forces and stresses in the tissue, which are mostly tensile, we have to include intracellular acto-myosin contraction into our simulation. We can then reproduce the experimentally observed behavior of cells moving around a circular obstacle, and suggest underlying mechanisms for cell-cell alignment and generation of traction force patterns.

  6. Bursts of activity in collective cell migration

    CERN Document Server

    Chepizhko, Oleksandr; Mastrapasqua, Eleonora; Nourazar, Mehdi; Ascagni, Miriam; Sugni, Michela; Fascio, Umberto; Leggio, Livio; Malinverno, Chiara; Scita, Giorgio; Santucci, Stephane; Alava, Mikko J; Zapperi, Stefano; La Porta, Caterina A M

    2016-01-01

    Dense monolayers of living cells display intriguing relaxation dynamics, reminiscent of soft and glassy materials close to the jamming transition, and migrate collectively when space is available, as in wound healing or in cancer invasion. Here we show that collective cell migration occurs in bursts that are similar to those recorded in the propagation of cracks, fluid fronts in porous media and ferromagnetic domain walls. In analogy with these systems, the distribution of activity bursts displays scaling laws that are universal in different cell types and for cells moving on different substrates. The main features of the invasion dynamics are quantitatively captured by a model of interacting active particles moving in a disordered landscape. Our results illustrate that collective motion of living cells is analogous to the corresponding dynamics in driven, but inanimate, systems.

  7. Tracking Mallards (Anas platyrhynchos) with GPS Satellite Transmitters Along Their Migration Route Through Northeast Asia.

    Science.gov (United States)

    Shin, Jeong-Hwa; Lee, Ki-Sup; Kim, Seol-Hee; Hwang, Jong-Kyung; Woo, Chanjin; Kim, Jiyeon; Kim, Jung-Hyun; Suh, Jae-Hwa; Jeong, Jipseol; Wang, Seung-Jun; Chung, Hyen-Mi; Yu, Seung-do; Choi, Kyung-Hee; Mo, In-Pil

    2016-05-01

    In this study, Global Positioning System satellite transmitters were attached to three mallards (Anas platyrhynchos) wintering in South Korea to track their migration routes, stopover sites, breeding sites, and migration patterns. We successfully tracked only one mallard (no. 108917) from November 15, 2011, to November 29, 2013, and determined separate migration routes in two cases of spring migration and one case of fall migration. The mallard repeatedly migrated to the same final destination, even though the travel path varied. We identified six stopover sites: Hunhe River, Liaohe River, Yinma River, Yalu River, Songjeon Bay, and Dahuofang Reservoir in China and South Korea. The wintering sites of two migration cases were discovered to be identical (Gokgyo River in Asan, South Korea). The terminal sites, which were presumed to be breeding grounds, were the same in both cases (Hinggan League in Inner Mongolia Autonomous Region, China). On the basis of the migration routes identified in this study, we suggest that future efforts to control highly pathogenic avian influenza (HPAI) should not only include avian influenza surveillance but also implement flyway-based strategies, with regard to all countries affected by potential HPAI outbreaks.

  8. Primary Cilia, Signaling Networks and Cell Migration

    DEFF Research Database (Denmark)

    Veland, Iben Rønn

    Primary cilia are microtubule-based, sensory organelles that emerge from the centrosomal mother centriole to project from the surface of most quiescent cells in the human body. Ciliary entry is a tightly controlled process, involving diffusion barriers and gating complexes that maintain a unique...... this controls directional cell migration as a physiological response. The ciliary pocket is a membrane invagination with elevated activity of clathrin-dependent endocytosis (CDE). In paper I, we show that the primary cilium regulates TGF-β signaling and the ciliary pocket is a compartment for CDE...... on formation of the primary cilium and CDE at the pocket region. The ciliary protein Inversin functions as a molecular switch between canonical and non-canonical Wnt signaling. In paper II, we show that Inversin and the primary cilium control Wnt signaling and are required for polarization and cell migration...

  9. Primary Cilia, Signaling Networks and Cell Migration

    DEFF Research Database (Denmark)

    Veland, Iben Rønn

    Primary cilia are microtubule-based, sensory organelles that emerge from the centrosomal mother centriole to project from the surface of most quiescent cells in the human body. Ciliary entry is a tightly controlled process, involving diffusion barriers and gating complexes that maintain a unique...... this controls directional cell migration as a physiological response. The ciliary pocket is a membrane invagination with elevated activity of clathrin-dependent endocytosis (CDE). In paper I, we show that the primary cilium regulates TGF-β signaling and the ciliary pocket is a compartment for CDE...... on formation of the primary cilium and CDE at the pocket region. The ciliary protein Inversin functions as a molecular switch between canonical and non-canonical Wnt signaling. In paper II, we show that Inversin and the primary cilium control Wnt signaling and are required for polarization and cell migration...

  10. Determinants of leader cells in collective cell migration.

    NARCIS (Netherlands)

    Khalil, A.; Friedl, P.H.A.

    2010-01-01

    Collective migration is a basic mechanism of cell translocation during morphogenesis, wound repair and cancer invasion. Collective movement requires cells to retain cell-cell contacts, exhibit group polarization with defined front-rear asymmetry, and consequently move as one multicellular unit. Depe

  11. Platelets Inhibit Migration of Canine Osteosarcoma Cells.

    Science.gov (United States)

    Bulla, S C; Badial, P R; Silva, R C; Lunsford, K; Bulla, C

    2017-01-01

    The interaction between platelets and tumour cells is important for tumour growth and metastasis. Thrombocytopenia or antiplatelet treatment negatively impact on cancer metastasis, demonstrating potentially important roles for platelets in tumour progression. To our knowledge, there is no information regarding the role of platelets in cancer progression in dogs. This study was designed to test whether canine platelets affected the migratory behaviour of three canine osteosarcoma cell lines and to give insights of molecular mechanisms. Intact platelets, platelet lysate and platelet releasate inhibited the migration of canine osteosarcoma cell lines. Addition of blood leucocytes to the platelet samples did not alter the inhibitory effect on migration. Platelet treatment also significantly downregulated the transcriptional levels of SNAI2 and TWIST1 genes. The interaction between canine platelets or molecules released during platelet activation and these tumour cell lines inhibits their migration, which suggests that canine platelets might antagonize metastasis of canine osteosarcoma. This effect is probably due to, at least in part, downregulation of genes related to epithelial-mesenchymal transition. Copyright © 2016. Published by Elsevier Ltd.

  12. Optimal chemotaxis in animal cell intermittent migration

    CERN Document Server

    Romanczuk, Pawel

    2015-01-01

    Animal cells can sense chemical gradients without moving, and are faced with the challenge of migrating towards a target despite noisy information on the target position. Here we discuss optimal search strategies for a chaser that moves by switching between two phases of motion ("run" and "tumble"), reorienting itself towards the target during tumble phases, and performing a persistent random walk during run phases. We show that the chaser average run time can be adjusted to minimize the target catching time or the spatial dispersion of the chasers. We obtain analytical results for the catching time and for the spatial dispersion in the limits of small and large ratios of run time to tumble time, and scaling laws for the optimal run times. Our findings have implications for optimal chemotactic strategies in animal cell migration.

  13. Preliminary study on migration pattern of the Tibetan antelope ( Pantholops hodgsonii) based on satellite tracking

    Science.gov (United States)

    Buho, Hoshino; Jiang, Z.; Liu, C.; Yoshida, T.; Mahamut, Halik; Kaneko, M.; Asakawa, M.; Motokawa, M.; Kaji, K.; Wu, X.; Otaishi, N.; Ganzorig, Sumiya; Masuda, R.

    2011-07-01

    The spatial and temporal patterns of the endangered Tibetan antelope or chiru ( Pantholops hodgsonii) have been studied using satellite-based ARGOS platform transmitter terminal (PTT) tracking data. The data was obtained from the satellite tracking of two female Tibetan antelopes that were collared with satellite transmitters and have been tracked from August 2007 to April 2009. Analysis of the locality data (LC) obtained, shows that both antelopes were migrant individuals, they shared the same calving ground surrounding lake Huiten (or Zhuonai lake), but different wintering pastures. Each antelope covered 250-300 km from the wintering to summer pastures. Annual range consisted of a core area that was used for at least 9 months; a calving ground used for a short time (from 8-20 days); and temporal pastures used during migration to and from the calving ground. Seasonal migration cycle was about 3 months, 27-30 days to reach the calving ground; 8-20 days staying there; and 36-40 days returning to the core area. Examination of the spatial distribution during migration showed that both chiru crossed the Qinghai-Tibetan railway (QTR) and the Golmud-Lhasa highway (GLH) at least two times, and reached calving ground (118-120 km from there) in 8 days, maintaining an average speed of 15 km per day. However, the return migration took twice as long (from 14 to 16 days). Each time, after reaching the QTR and GLH, the antelopes spent 20-40 days in that area, probably looking for passages and waiting. So far, we suppose that the QTR and the GLH have become a hindrance to the migration of the Tibetan antelopes and seriously delay their movement to and from the calving area. Extended aggregation of the herds of Tibetan antelopes along the QTR and the GLH may impact negatively with increased mortality among offspring, the spread of various diseases and overgrazing of pastures.

  14. Taking Aim at Moving Targets in Computational Cell Migration.

    Science.gov (United States)

    Masuzzo, Paola; Van Troys, Marleen; Ampe, Christophe; Martens, Lennart

    2016-02-01

    Cell migration is central to the development and maintenance of multicellular organisms. Fundamental understanding of cell migration can, for example, direct novel therapeutic strategies to control invasive tumor cells. However, the study of cell migration yields an overabundance of experimental data that require demanding processing and analysis for results extraction. Computational methods and tools have therefore become essential in the quantification and modeling of cell migration data. We review computational approaches for the key tasks in the quantification of in vitro cell migration: image pre-processing, motion estimation and feature extraction. Moreover, we summarize the current state-of-the-art for in silico modeling of cell migration. Finally, we provide a list of available software tools for cell migration to assist researchers in choosing the most appropriate solution for their needs.

  15. Collective cell migration: Implications for wound healing and cancer invasion

    Directory of Open Access Journals (Sweden)

    Li Li

    2013-07-01

    Full Text Available During embryonic morphogenesis, wound repair and cancer invasion, cells often migrate collectively via tight cell-cell junctions, a process named collective migration. During such migration, cells move as coherent groups, large cell sheets, strands or tubes rather than individually. One unexpected finding regarding collective cell migration is that being a "multicellular structure" enables cells to better respond to chemical and physical cues, when compared with isolated cells. This is important because epithelial cells heal wounds via the migration of large sheets of cells with tight intercellular connections. Recent studies have gained some mechanistic insights that will benefit the clinical understanding of wound healing in general. In this review, we will briefly introduce the role of collective cell migration in wound healing, regeneration and cancer invasion and discuss its underlying mechanisms as well as implications for wound healing.

  16. Rho family proteins in cell adhesion and cell migration.

    Science.gov (United States)

    Evers, E E; Zondag, G C; Malliri, A; Price, L S; ten Klooster, J P; van der Kammen, R A; Collard, J G

    2000-06-01

    Cell migration and the regulation of cadherin-mediated homotypic cell-cell interactions are critical events during development, morphogenesis and wound healing. Aberrations in signalling pathways involved in the regulation of cell migration and cadherin-mediated cell-cell adhesion contribute to tumour invasion and metastasis. The rho family proteins, including cdc42, rac1 and rhoA, regulate signalling pathways that mediate the distinct actin cytoskeleton changes required for both cellular motility and cell-cell adhesion. Recent studies indicate that rac directly influences rho activity at the GTPase level and that the reciprocal balance between rac and rho activity can determine epithelial or mesenchymal cell morphology and migratory behaviour of epithelial (tumour) cells.

  17. Globular adiponectin activates motility and regenerative traits of muscle satellite cells.

    Directory of Open Access Journals (Sweden)

    Tania Fiaschi

    Full Text Available Regeneration of adult injured skeletal muscle is due to activation of satellite cells, a population of stem cells resident beneath the basal lamina. Thus, information on soluble factors affecting satellite cell activation, as well as migration towards injury and fusion into new myofibers are essential. Here, we show that globular adiponectin (gAd, positively affects several features of muscle satellite cells. gAd activates satellite cells to exit quiescence and increases their recruitment towards myotubes. gAd elicits in satellite cells a specific motility program, involving activation of the small GTPase Rac1, as well as expression of Snail and Twist transcription factors driving a proteolytic motility, useful to reach the site of injury. We show that satellite cells produce autocrine full length adiponectin (fAd, which is converted to gAd by activated macrophages. In turns, gAd concurs to attract to the site of injury both satellite cells and macrophages and induces myogenesis in muscle satellite cells. Thus, these findings add a further role for gAd in skeletal muscle, including the hormone among factors participating in muscle regeneration.

  18. Quercetin Inhibits Cell Migration and Invasion in Human Osteosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Haifeng Lan

    2017-09-01

    Full Text Available Background/Aims: Osteosarcoma is a malignant tumor associated with high mortality; however, no effective therapies for the disease have been developed. Several studies have focused on elucidating the pathogenesis of osteosarcoma and have aimed to develop novel therapies for the disease. Quercetin is a vital dietary flavonoid that has been shown to have a variety of anticancer effects, as it induces cell cycle arrest, apoptosis, and differentiation and is involved in cell adhesion, metastasis and angiogenesis. Herein, we aimed to investigate the effects of quercetin on osteosarcoma migration and invasion in vitro and in vivo and to explore the molecular mechanisms underlying its effects on osteosarcoma migration and invasion. Methods: Cell viability, cell cycle activity and cell apoptosis were measured using CCK-8 assay and flow cytometry, and cell migration and invasion were evaluated by wound healing and transwell assays, respectively. The mRNA and protein expression levels of several proteins of interest were assessed by real-time quantitative PCR and western blotting, respectively. Moreover, a nude mouse model of human osteosarcoma lung metastasis was established to assess the anti-metastatic effects of quercetin in vivo. Results: We noted no significant differences in cell cycle activity and apoptosis between HOS and MG63 cells and control cells. Treatment with quercetin significantly attenuated cell migration and invasion in HOS and MG63 cells compared with treatment with control medium. Moreover HIF-1α, VEGF, MMP2, and MMP9 mRNA and protein expression levels were significantly downregulated in HOS cells treated with quercetin compared with HOS cells treated with controls. Additionally, treatment with quercetin attenuated metastatic lung tumor formation and growth in the nude mouse model of osteosarcoma compared with treatment with controls. Conclusion: Our findings regarding the inhibitory effects of quercetin on cell migration and

  19. Satellite tracking of the migration of Whooper Swans Cygnus cygnus wintering in Japan

    Science.gov (United States)

    Shimada, Tetsuo; Yamaguchi, Noriyuki M.; Hijikata, N.; Hiraoka, Emiko N.; Hupp, Jerry; Flint, Paul L.; Tokita, Ken-ichi; Fujita, Go; Uchida, Kiyoshi; Sato, F.; Kurechi, Masayuki; Pearce, John M.; Ramey, Andy M.; Higuchi, Hiroyoshi

    2014-01-01

    We satellite-tracked Whooper Swans Cygnus cygnus wintering in northern Japan to document their migration routes and timing, and to identify breeding areas. From 47 swans that we marked at Lake Izunuma-Uchinuma, Miyagi Prefecture, northeast Honshu, and at Lake Kussharo, east Hokkaido, we observed 57 spring and 33 autumn migrations from 2009-2012. In spring, swans migrated north along Sakhalin Island from eastern Hokkaido using stopovers in Sakhalin, at the mouth of the Amur River and in northern coastal areas of the Sea of Okhotsk. They ultimately reached molting/breedmg areas along the Indigirka River and the lower Kolyma River in northern Russia. In autumn, the swans basically reversed the spring migration routes. We identified northern Honshu, eastern Hokkaido, coastal areas in Sakhalin, the lower Amur River and northern coastal areas of the Sea of Okhotsk as the most frequent stopover sites, and the middle reaches of the Indigirka and the lower Kolyma River as presumed breeding sites. Our results are helpful in understanding the distribution of the breeding and stopover sites of Whooper Swans wintering in Japan and in identifying their major migration habitats. Our findings contribute to understanding the potential transmission process of avian influenza viruses potentially carried by swans, and provide information necessary to conserve Whooper Swans in East Asia.

  20. Satellite- versus temperature-derived green wave indices for predicting the timing of spring migration of avian herbivores

    NARCIS (Netherlands)

    Shariati Najafabadi, M.; Darvishzadeh, R.; Skidmore, A.K.; Kölzsch, A.; Vrieling, A.; Nolet, B.A.; Exo, K.; Meratnia, N.; Havinga, P.J.M.; Stahl, J.; Toxopeus, A.G.

    2015-01-01

    According to the green wave hypothesis, herbivores follow the flush of spring growth of forage plants during their spring migration to northern breeding grounds. In this study we compared two green wave indices for predicting the timing of the spring migration of avian herbivores: the satellite-deri

  1. T cell migration in rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Mario eMellado

    2015-07-01

    Full Text Available Rheumatoid arthritis (RA is an autoimmune disease characterized by chronic inflammation in joints, associated with synovial hyperplasia and with bone and cartilage destruction. Although the primacy of T cell-related events early in the disease continues to be debated, there is strong evidence that autoantigen recognition by specific T cells is crucial to the pathophysiology of rheumatoid synovitis. In addition, T cells are key components of the immune cell infiltrate detected in the joints of RA patients. Initial analysis of the cytokines released into the synovial membrane showed an imbalance, with a predominance of proinflammatory mediators, indicating a deleterious effect of Th1 T cells. There is nonetheless evidence that Th17 cells also play an important role in RA. T cells migrate from the bloodstream to the synovial tissue via their interactions with the endothelial cells that line synovial postcapillary venules. At this stage, selectins, integrins and chemokines have a central role in blood cell invasion of synovial tissue, and therefore in the intensity of the inflammatory response.In this review we will focus on the mechanisms involved in T cell attraction to the joint, the proteins involved in their extravasation from blood vessels, and the signaling pathways activated. Knowledge of these processes will lead to a better understanding of the mechanism by which the systemic immune response causes local joint disorders and will help to provide a molecular basis for therapeutic strategies.

  2. Cell shape dynamics: from waves to migration.

    Directory of Open Access Journals (Sweden)

    Meghan K Driscoll

    Full Text Available We observe and quantify wave-like characteristics of amoeboid migration. Using the amoeba Dictyostelium discoideum, a model system for the study of chemotaxis, we demonstrate that cell shape changes in a wave-like manner. Cells have regions of high boundary curvature that propagate from the leading edge toward the back, usually along alternating sides of the cell. Curvature waves are easily seen in cells that do not adhere to a surface, such as cells that are electrostatically repelled from surfaces or cells that extend over the edge of micro-fabricated cliffs. Without surface contact, curvature waves travel from the leading edge to the back of a cell at -35 µm/min. Non-adherent myosin II null cells do not exhibit these curvature waves. At the leading edge of adherent cells, curvature waves are associated with protrusive activity. Like regions of high curvature, protrusive activity travels along the boundary in a wave-like manner. Upon contact with a surface, the protrusions stop moving relative to the surface, and the boundary shape thus reflects the history of protrusive motion. The wave-like character of protrusions provides a plausible mechanism for the zig-zagging of pseudopods and for the ability of cells both to swim in viscous fluids and to navigate complex three dimensional topography.

  3. Desmosome dynamics in migrating epithelial cells requires the actin cytoskeleton

    Science.gov (United States)

    Roberts, Brett J.; Pashaj, Anjeza; Johnson, Keith R.; Wahl, James K.

    2011-01-01

    Re-modeling of epithelial tissues requires that the cells in the tissue rearrange their adhesive contacts in order to allow cells to migrate relative to neighboring cells. Desmosomes are prominent adhesive structures found in a variety of epithelial tissues that are believed to inhibit cell migration and invasion. Mechanisms regulating desmosome assembly and stability in migrating cells are largely unknown. In this study we established a cell culture model to examine the fate of desmosomal components during scratch wound migration. Desmosomes are rapidly assembled between epithelial cells at the lateral edges of migrating cells and structures are transported in a retrograde fashion while the structures become larger and mature. Desmosome assembly and dynamics in this system are dependent on the actin cytoskeleton prior to being associated with the keratin intermediate filament cytoskeleton. These studies extend our understanding of desmosome assembly and provide a system to examine desmosome assembly and dynamics during epithelial cell migration. PMID:21945137

  4. Muscle Satellite Cell Heterogeneity and Self-Renewal

    Directory of Open Access Journals (Sweden)

    Norio eMotohashi

    2014-01-01

    Full Text Available Adult skeletal muscle possesses extraordinary regeneration capacities. After muscle injury or exercise, large numbers of newly formed muscle fibers are generated within a week as a result of expansion and differentiation of a self-renewing pool of muscle stem cells termed muscle satellite cells. Normally, satellite cells are mitotically quiescent and reside beneath the basal lamina of muscle fibers. Upon regeneration, satellite cells are activated, and give rise to daughter myogenic precursor cells. After several rounds of proliferation, these myogenic precursor cells contribute to the formation of new muscle fibers. During cell division, a minor population of myogenic precursor cells returns to quiescent satellite cells as a self-renewal process. Currently, accumulating evidence has revealed the essential roles of satellite cells in muscle regeneration and the regulatory mechanisms, while it still remains to be elucidated how satellite cell self-renewal is molecularly regulated and how satellite cells are important in aging and diseased muscle. The number of satellite cells is decreased due to the changing niche during ageing, resulting in attenuation of muscle regeneration capacity. Additionally, in Duchenne muscular dystrophy (DMD patients, the loss of satellite cell regenerative capacity and decreased satellite cell number due to continuous needs for satellite cells lead to progressive muscle weakness with chronic degeneration. Thus, it is necessary to replenish muscle satellite cells continuously. This review outlines recent findings regarding satellite cell heterogeneity, asymmetric division and molecular mechanisms in satellite cell self-renewal which is crucial for maintenance of satellite cells as a muscle stem cell pool throughout life. In addition, we discuss roles in the stem cell niche for satellite cell maintenance, as well as related cell therapies for approaching treatment of DMD.

  5. Flow-driven cell migration under external electric fields

    Science.gov (United States)

    Li, Yizeng; Mori, Yoichiro; Sun, Sean X.

    2016-01-01

    Electric fields influence many aspects of cell physiology, including various forms of cell migration. Many cells are sensitive to electric fields, and can migrate toward a cathode or an anode, depending on the cell type. In this paper, we examine an actomyosin-independent mode of cell migration under electrical fields. Our theory considers a one-dimensional cell with water and ionic fluxes at the cell boundary. Water fluxes through the membrane are governed by the osmotic pressure difference across the cell membrane. Fluxes of cations and anions across the cell membrane are determined by the properties of the ion channels as well as the external electric field. Results show that without actin polymerization and myosin contraction, electric fields can also drive cell migration, even when the cell is not polarized. The direction of migration with respect to the electric field direction is influenced by the properties of ion channels, and are cell-type dependent. PMID:26765031

  6. Microfluidic device with dual mechanical cues for cell migration investigation.

    Science.gov (United States)

    Tsai, Chin-Hsiung; Kuo, Po-Ling

    2013-01-01

    Cell migration plays an important role in numerous physiological and pathological conditions, such as angiogenesis, wound healing and cancer metastasis. Understanding the fundamental mechanisms of cell migration is crucial to develop strategies for disease treatment and regenerative medicine. Several biomechanical cues have been well studied about their effects on guiding cell migration. However, the effects of dual or multiple cues on cell migration are barely addressed. In this work, we developed a microfluidic-based device to study the combinatory effects of osmotic and stiffness gradient on cell migration. Computer simulation and experimental validation showed that the device was capable of providing stable osmotic and stiffness gradient to cultured cells at the same time. Preliminary results suggest that our device has a valuable potential in studying cell migration in complex conditions which better recapitulate the complex environmental conditions in vivo.

  7. Skeletal Muscle Satellite Cell Activation Following Cutaneous Burn in Rats

    Science.gov (United States)

    2013-12-01

    Satellite cell isolation and culture Satellite cells were isolated similar as described by Allen et al. [30]. Following euthanasia , muscles were...satellite cell cultures. Methods Cell Biol 1997;52:155–76. [31] Tatsumi R, Liu X, Pulido A, Morales M, Sakata T, Dial S, Hattori A, Ikeuchi Y, Allen RE

  8. Fine Tuning Cell Migration by a Disintegrin and Metalloproteinases

    Science.gov (United States)

    Theodorou, K.

    2017-01-01

    Cell migration is an instrumental process involved in organ development, tissue homeostasis, and various physiological processes and also in numerous pathologies. Both basic cell migration and migration towards chemotactic stimulus consist of changes in cell polarity and cytoskeletal rearrangement, cell detachment from, invasion through, and reattachment to their neighboring cells, and numerous interactions with the extracellular matrix. The different steps of immune cell, tissue cell, or cancer cell migration are tightly coordinated in time and place by growth factors, cytokines/chemokines, adhesion molecules, and receptors for these ligands. This review describes how a disintegrin and metalloproteinases interfere with several steps of cell migration, either by proteolytic cleavage of such molecules or by functions independent of proteolytic activity. PMID:28260841

  9. Fine Tuning Cell Migration by a Disintegrin and Metalloproteinases.

    Science.gov (United States)

    Dreymueller, D; Theodorou, K; Donners, M; Ludwig, A

    2017-01-01

    Cell migration is an instrumental process involved in organ development, tissue homeostasis, and various physiological processes and also in numerous pathologies. Both basic cell migration and migration towards chemotactic stimulus consist of changes in cell polarity and cytoskeletal rearrangement, cell detachment from, invasion through, and reattachment to their neighboring cells, and numerous interactions with the extracellular matrix. The different steps of immune cell, tissue cell, or cancer cell migration are tightly coordinated in time and place by growth factors, cytokines/chemokines, adhesion molecules, and receptors for these ligands. This review describes how a disintegrin and metalloproteinases interfere with several steps of cell migration, either by proteolytic cleavage of such molecules or by functions independent of proteolytic activity.

  10. Migration of Tundra Swans (Cygnus columbianus) Wintering in Japan Using Satellite Tracking: Identification of the Eastern Palearctic Flyway.

    Science.gov (United States)

    Chen, Wenbo; Doko, Tomoko; Fujita, Go; Hijikata, Naoya; Tokita, Ken-Ichi; Uchida, Kiyoshi; Konishi, Kan; Hiraoka, Emiko; Higuchi, Hiroyoshi

    2016-02-01

    Migration through the Eastern Palearctic (EP) flyway by tundra swans (Cygnus columbianus) has not been thoroughly documented. We satellite-tracked the migration of 16 tundra swans that winter in Japan. The objectives of this study were 1) to show the migration pattern of the EP flyway of tundra swans; 2) to compare this pattern with the migration pattern of whooper swans; and 3) to identify stopover sites that are important for these swans' conservation. Tundra swans were captured at Kutcharo Lake, Hokkaido, in 2009-2012 and satellite-tracked. A new method called the "MATCHED (Migratory Analytical Time Change Easy Detection) method" was developed. Based on median, the spring migration began on 18 April and ended on 27 May. Autumn migration began on 9 September and ended on 2 November. The median duration of the spring and autumn migrations were 48 and 50 days, respectively. The mean duration at one stopover site was 5.5 days and 6.8 days for the spring and autumn migrations, respectively. The number of stopover sites was 3.0 and 2.5 for the spring and autumn migrations, respectively. The mean travel distances for the spring and autumn migrations were 6471 and 6331 km, respectively. Seven migration routes passing Sakhalin, the Amur River, and/or Kamchatka were identified. There were 15, 32, and eight wintering, stopover, and breeding sites, respectively. The migration routes and staging areas of tundra swans partially overlap with those of whooper swans, whose migration patterns have been previously documented. The migration patterns of these two swan species that winter in Japan confirm the importance of the Amur River, Udyl' Lake, Shchastya Bay, Aniva Bay, zaliv Chayvo Lake, zal Piltun Lake, zaliv Baykal Lake, Kolyma River, Buyunda River, Sen-kyuyel' Lake, and northern coastal areas of the Sea of Okhotsk.

  11. Isolation and Culture of Satellite Cells from Mouse Skeletal Muscle.

    Science.gov (United States)

    Musarò, Antonio; Carosio, Silvia

    2017-01-01

    Skeletal muscle tissue is characterized by a population of quiescent mononucleated myoblasts, localized between the basal lamina and sarcolemma of myofibers, known as satellite cells. Satellite cells play a pivotal role in muscle homeostasis and are the major source of myogenic precursors in mammalian muscle regeneration.This chapter describes protocols for isolation and culturing satellite cells isolated from mouse skeletal muscles. The classical procedure, which will be discussed extensively in this chapter, involves the enzymatic dissociation of skeletal muscles, while the alternative method involves isolation of satellite cells from isolated myofibers in which the satellite cells remain in their in situ position underneath the myofiber basal lamina.In particular, we discuss the technical aspect of satellite cell isolation, the methods necessary to enrich the satellite cell fraction and the culture conditions that optimize proliferation and myotube formation of mouse satellite cells.

  12. BMP signaling regulates satellite cell-dependent postnatal muscle growth.

    Science.gov (United States)

    Stantzou, Amalia; Schirwis, Elija; Swist, Sandra; Alonso-Martin, Sonia; Polydorou, Ioanna; Zarrouki, Faouzi; Mouisel, Etienne; Beley, Cyriaque; Julien, Anaïs; Le Grand, Fabien; Garcia, Luis; Colnot, Céline; Birchmeier, Carmen; Braun, Thomas; Schuelke, Markus; Relaix, Frédéric; Amthor, Helge

    2017-08-01

    Postnatal growth of skeletal muscle largely depends on the expansion and differentiation of resident stem cells, the so-called satellite cells. Here, we demonstrate that postnatal satellite cells express components of the bone morphogenetic protein (BMP) signaling machinery. Overexpression of noggin in postnatal mice (to antagonize BMP ligands), satellite cell-specific knockout of Alk3 (the gene encoding the BMP transmembrane receptor) or overexpression of inhibitory SMAD6 decreased satellite cell proliferation and accretion during myofiber growth, and ultimately retarded muscle growth. Moreover, reduced BMP signaling diminished the adult satellite cell pool. Abrogation of BMP signaling in satellite cell-derived primary myoblasts strongly diminished cell proliferation and upregulated the expression of cell cycle inhibitors p21 and p57 In conclusion, these results show that BMP signaling defines postnatal muscle development by regulating satellite cell-dependent myofiber growth and the generation of the adult muscle stem cell pool. © 2017. Published by The Company of Biologists Ltd.

  13. Bird migration and avian influenza: a comparison of hydrogen stable isotopes and satellite tracking methods

    Science.gov (United States)

    Bridge, Eli S.; Kelly, Jeffrey F.; Xiao, Xiangming; Takekawa, John Y.; Hill, Nichola J.; Yamage, Mat; Haque, Enam Ul; Islam, Mohammad Anwarul; Mundkur, Taej; Yavuz, Kiraz Erciyas; Leader, Paul; Leung, Connie Y.H.; Smith, Bena; Spragens, Kyle A.; Vandegrift, Kurt J.; Hosseini, Parviez R.; Saif, Samia; Mohsanin, Samiul; Mikolon, Andrea; Islam, Ausrafal; George, Acty; Sivananinthaperumal, Balachandran; Daszak, Peter; Newman, Scott H.

    2014-01-01

    Satellite-based tracking of migratory waterfowl is an important tool for understanding the potential role of wild birds in the long-distance transmission of highly pathogenic avian influenza. However, employing this technique on a continental scale is prohibitively expensive. This study explores the utility of stable isotope ratios in feathers in examining both the distances traveled by migratory birds and variation in migration behavior. We compared the satellite-derived movement data of 22 ducks from 8 species captured at wintering areas in Bangladesh, Turkey, and Hong Kong with deuterium ratios (δD) in the feathers of these and other individuals captured at the same locations. We derived likely molting locations from the satellite tracking data and generated expected isotope ratios based on an interpolated map of δD in rainwater. Although δD was correlated with the distance between wintering and molting locations, surprisingly, measured δD values were not correlated with either expected values or latitudes of molting sites. However, population-level parameters derived from the satellite-tracking data, such as mean distance between wintering and molting locations and variation in migration distance, were reflected by means and variation of the stable isotope values. Our findings call into question the relevance of the rainfall isotope map for Asia for linking feather isotopes to molting locations, and underscore the need for extensive ground truthing in the form of feather-based isoscapes. Nevertheless, stable isotopes from feathers could inform disease models by characterizing the degree to which regional breeding populations interact at common wintering locations. Feather isotopes also could aid in surveying wintering locations to determine where high-resolution tracking techniques (e.g. satellite tracking) could most effectively be employed. Moreover, intrinsic markers such as stable isotopes offer the only means of inferring movement information from

  14. Characterization of the role of RILP in cell migration

    Directory of Open Access Journals (Sweden)

    Azzurra Margiotta

    2017-05-01

    Full Text Available Rab-interacting lysosomal protein (RILP is a regulator of late stages of endocytosis. Recent work proved that depletion of RILP promotes migration of breast cancer cells in wound healing assay, whereas its overexpression influences re-arrangements of actin cytoskeleton. Here, we further characterized the role of RILP in cell migration by analyzing several aspects of this process. We showed that RILP is fundamental also for migration of lung cancer cells regulating cell velocity. RILP silencing did not affect Golgi apparatus nor microtubules reorientation during migration. However, both RILP over-expression and expression of its mutated form, RILP-C33, impair cell adhesion and spreading. In conclusion, our results demonstrate that RILP has important regulatory roles in cell motility affecting migration velocity but also in cell adhesion and cell spreading.

  15. Directional Cell Migration in Response to Repeated Substratum Stretching

    Science.gov (United States)

    Okimura, Chika; Iwadate, Yoshiaki

    2017-10-01

    Crawling migration plays an essential role in a variety of biological phenomena, including development, wound healing, and immune system function. Migration properties such as anterior-posterior polarity, directionality, and velocity are regulated not only by the reception of a chemoattractant but also by sensing mechanical inputs from the external environment. In this review, we describe the mechanical response of migrating cells, particularly under repeated stretching of the elastic substratum, highlighting the fact that there appear to be two independent mechanosensing systems that generate the polarity needed for migration. Cells that have no stress fibers, such as Dictyostelium cells and neutrophil-like differentiated HL-60 cells, migrate perpendicular to the stretching direction via myosin II localization. Cells that do possess stress fibers, however, such as fish keratocytes, migrate parallel to the stretching via a stress-fiber-dependent process.

  16. Modeling Bird Migration in Changing Habitats: Space-based Ornithology using Satellites and GIS

    Science.gov (United States)

    Smith, James A.; Deppe, Jill L.

    2008-01-01

    Understanding bird migration and avian biodiversity is one of the most compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties presenting challenges in both geographic space and time. Space based technology, coupled with geographic information systems, yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At NASA, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. In our work, we use individual organism biophysical models and drive these models with satellite observations and numerical weather predictions of the spatio-temporal gradients in climate and habitat. Geographic information system technology comprises one component of our overall simulation framework, especially for characterizing the changing habitats and conditions encountered by en-route migratory birds. Simulation provides a tool for studying bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. Such models yield an understanding of how a migratory flyway and its component habitats function as a whole and link stop-over ecology with biological conservation and management. We present examples of our simulation of shorebirds, principally, pectoral sandpipers, along the central flyways of the United States and Canada from the Gulf of Mexico to Alaska.

  17. Modeling Bird Migration in Changing Habitats: Space-based Ornithology using Satellites and GIS

    Science.gov (United States)

    Smith, James A.; Deppe, Jill L.

    2008-01-01

    Understanding bird migration and avian biodiversity is one of the most compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties presenting challenges in both geographic space and time. Space based technology, coupled with geographic information systems, yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At NASA, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. In our work, we use individual organism biophysical models and drive these models with satellite observations and numerical weather predictions of the spatio-temporal gradients in climate and habitat. Geographic information system technology comprises one component of our overall simulation framework, especially for characterizing the changing habitats and conditions encountered by en-route migratory birds. Simulation provides a tool for studying bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. Such models yield an understanding of how a migratory flyway and its component habitats function as a whole and link stop-over ecology with biological conservation and management. We present examples of our simulation of shorebirds, principally, pectoral sandpipers, along the central flyways of the United States and Canada from the Gulf of Mexico to Alaska.

  18. Lutein Inhibits the Migration of Retinal Pigment Epithelial Cells via Cytosolic and Mitochondrial Akt Pathways (Lutein Inhibits RPE Cells Migration

    Directory of Open Access Journals (Sweden)

    Ching-Chieh Su

    2014-08-01

    Full Text Available During the course of proliferative vitreoretinopathy (PVR, the retinal pigment epithelium (RPE cells will de-differentiate, proliferate, and migrate onto the surfaces of the sensory retina. Several studies have shown that platelet-derived growth factor (PDGF can induce migration of RPE cells via an Akt-related pathway. In this study, the effect of lutein on PDGF-BB-induced RPE cells migration was examined using transwell migration assays and Western blot analyses. We found that both phosphorylation of Akt and mitochondrial translocation of Akt in RPE cells induced by PDGF-BB stimulation were suppressed by lutein. Furthermore, the increased migration observed in RPE cells with overexpressed mitochondrial Akt could also be suppressed by lutein. Our results demonstrate that lutein can inhibit PDGF-BB induced RPE cells migration through the inhibition of both cytoplasmic and mitochondrial Akt activation.

  19. Proliferation conditions for human satellite cells. The fractional content of satellite cells

    DEFF Research Database (Denmark)

    Gaster, M; Beck-Nielsen, H; Schrøder, H D

    2001-01-01

    the fraction of Sc in culture. Evaluation of different culture conditions allowed us to find proliferation conditions preferentially for Sc: a) Sc should be cultured on surfaces coated with ECM-gel. b) Primary cell culture should be inoculated in DMEM supplemented with 10% fetal calf serum to increase cell......Primary satellite cell cultures have become an important tool as a model system for skeletal muscles. A common problem in human satellite cell culturing is fibroblast overgrowth. We combined N-CAM (Leu19) immunocytochemical staining of satellite cells (Sc) with stereological methods to estimate...... adherence. c) Change of media to DMEM supplemented with 2% Ultroser-G and 2% FCS after 24 h.d) Before subcultivation, cells should be preplated for 30 min. The fractional content of Sc in passage four when applying this method of cultivation was 0.82 +/- 0.07 (mean +/- SE, N = 10). Our method enabled us...

  20. Cell migration towards CXCL12 in leukemic cells compared to breast cancer cells.

    Science.gov (United States)

    Mills, Shirley C; Goh, Poh Hui; Kudatsih, Jossie; Ncube, Sithembile; Gurung, Renu; Maxwell, Will; Mueller, Anja

    2016-04-01

    Chemotaxis or directed cell migration is mediated by signalling events initiated by binding of chemokines to their cognate receptors and the activation of a complex signalling cascade. The molecular signalling pathways involved in cell migration are important to understand cancer cell metastasis. Therefore, we investigated the molecular mechanisms of CXCL12 induced cell migration and the importance of different signalling cascades that become activated by CXCR4 in leukemic cells versus breast cancer cells. We identified Src kinase as being essential for cell migration in both cancer types, with strong involvement of the Raf/MEK/ERK1/2 pathway. We did not detect any involvement of Ras or JAK2/STAT3 in CXCL12 induced migration in Jurkat cells. Preventing PKC activation with inhibitors does not affect migration in Jurkat cells at all, unlike in the adherent breast cancer cell line MCF-7 cells. However, in both cell lines, knock down of PKCα prevents migration towards CXCL12, whereas the expression of PKCζ is less crucial for migration. PI3K activation is essential in both cell types, however LY294002 usage in MCF-7 cells does not block migration significantly. These results highlight the importance of verifying specific signalling pathways in different cell settings and with different approaches.

  1. Migration and wintering sites of Pelagic Cormorants determined by satellite telemetry

    Science.gov (United States)

    Hatch, Shyla A.; Gill, V.A.; Mulcahy, D.M.

    2011-01-01

    Factors affecting winter survival may be key determinants of status and population trends of seabirds, but connections between breeding sites and wintering areas of most populations are poorly known. Pelagic Cormorants (Phalacrocorax pelagicus; N= 6) surgically implanted with satellite transmitters migrated from a breeding colony on Middleton Island, northern Gulf of Alaska, to wintering sites in southeast Alaska and northern British Columbia. Winter locations averaged 920 km (range = 600-1190 km) from the breeding site. Migration flights in fall and spring lasted ???5 d in four instances. After reaching wintering areas, cormorants settled in narrowly circumscribed inshore locations (~10-km radius) and remained there throughout the nonbreeding period (September- March). Two juveniles tagged at the breeding colony as fledglings remained at their wintering sites for the duration of the tracking interval (14 and 22 mo, respectively). Most cormorants used multiple sites within their winter ranges for roosting and foraging. Band recoveries show that Pelagic Cormorants in southern British Columbia and Washington disperse locally in winter, rather than migrating like the cormorants in our study. Radio-tagging and monitoring cormorants and other seabirds from known breeding sites are vital for understanding migratory connectivity and improving conservation strategies for local populations. ?? 2011 The Authors. Journal of Field Ornithology ?? 2011 Association of Field Ornithologists.

  2. Multi-cellular logistics of collective cell migration.

    Directory of Open Access Journals (Sweden)

    Masataka Yamao

    Full Text Available During development, the formation of biological networks (such as organs and neuronal networks is controlled by multicellular transportation phenomena based on cell migration. In multi-cellular systems, cellular locomotion is restricted by physical interactions with other cells in a crowded space, similar to passengers pushing others out of their way on a packed train. The motion of individual cells is intrinsically stochastic and may be viewed as a type of random walk. However, this walk takes place in a noisy environment because the cell interacts with its randomly moving neighbors. Despite this randomness and complexity, development is highly orchestrated and precisely regulated, following genetic (and even epigenetic blueprints. Although individual cell migration has long been studied, the manner in which stochasticity affects multi-cellular transportation within the precisely controlled process of development remains largely unknown. To explore the general principles underlying multicellular migration, we focus on the migration of neural crest cells, which migrate collectively and form streams. We introduce a mechanical model of multi-cellular migration. Simulations based on the model show that the migration mode depends on the relative strengths of the noise from migratory and non-migratory cells. Strong noise from migratory cells and weak noise from surrounding cells causes "collective migration," whereas strong noise from non-migratory cells causes "dispersive migration." Moreover, our theoretical analyses reveal that migratory cells attract each other over long distances, even without direct mechanical contacts. This effective interaction depends on the stochasticity of the migratory and non-migratory cells. On the basis of these findings, we propose that stochastic behavior at the single-cell level works effectively and precisely to achieve collective migration in multi-cellular systems.

  3. HIF-1α Promotes A Hypoxia-Independent Cell Migration.

    Science.gov (United States)

    Li, Liyuan; Madu, Chikezie O; Lu, Andrew; Lu, Yi

    2010-01-01

    Hypoxia-inducible factor-1α (HIF-1α) is known as a transactivator for VEGF gene promoter. It can be induced by hypoxia. However, no study has been done so far to dissect HIF-1α-mediated effects from hypoxia or VEGF-mediated effects. By using a HIF-1α knockout (HIF-1α KO) cell system in mouse embryonic fibroblast (MEF) cells, this study analyzes cell migration and HIF-1α, hypoxia and VEGF activation. A hypoxia-mediated HIF-1α induction and VEGF transactivation were observed: both HIF-1α WT lines had significantly increased VEGF transactivation, as an indicator for HIF-1α induction, in hypoxia compared to normoxia; in contrast, HIF-1α KO line had no increased VEGF transactivation under hypoxia. HIF-1α promotes cell migration: HIF-1α-KO cells had a significantly reduced migration compared to that of the HIF-1α WT cells under both normoxia and hypoxia. The significantly reduced cell migration in HIF-1α KO cells can be partially rescued by the restoration of WT HIF-1α expression mediated by adenoviral-mediated gene transfer. Interestingly, hypoxia has no effect on cell migration: the cells had a similar cell migration rate under hypoxic and normoxic conditions for both HIF-1α WT and HIF-1α KO lines, respectively. Collectively, these data suggest that HIF-1α plays a role in MEF cell migration that is independent from hypoxia-mediated effects.

  4. Leader Cells Define Directionality of Trunk, but Not Cranial, Neural Crest Cell Migration

    Directory of Open Access Journals (Sweden)

    Jo Richardson

    2016-05-01

    Full Text Available Collective cell migration is fundamental for life and a hallmark of cancer. Neural crest (NC cells migrate collectively, but the mechanisms governing this process remain controversial. Previous analyses in Xenopus indicate that cranial NC (CNC cells are a homogeneous population relying on cell-cell interactions for directional migration, while chick embryo analyses suggest a heterogeneous population with leader cells instructing directionality. Our data in chick and zebrafish embryos show that CNC cells do not require leader cells for migration and all cells present similar migratory capacities. In contrast, laser ablation of trunk NC (TNC cells shows that leader cells direct movement and cell-cell contacts are required for migration. Moreover, leader and follower identities are acquired before the initiation of migration and remain fixed thereafter. Thus, two distinct mechanisms establish the directionality of CNC cells and TNC cells. This implies the existence of multiple molecular mechanisms for collective cell migration.

  5. Satellite tracking of two lesser spotted eagles Aquila pomarina, migrating from Namibia

    Science.gov (United States)

    Meyburg, B.-U.; Ellis, D.H.; Meyburg, C.; Mendelsohn, J.; Scheller, W.

    2001-01-01

    One immature and one subadult Lesser Spotted Eagle, Aquila pomarina, were followed by satellite telemetry from their non-breeding areas in Namibia. Both birds were fitted with transmitters (PTTs) in February 1994 and tracked, the immature for six months and two weeks, over distances of 10084 and 16773 km, respectively. During their time in Namibia both birds? movements were in response to good local rainfall. The immature eagle left Namibia at the end of February, the subadult at the end of March. They flew to their respective summer quarters in Hungary and the Ukraine, arriving there 2.5 and 1.5 months later than the breeding adults. The immature eagle took over two months longer on the homeward journey than a breeding male followed by telemetry in a previous study. On returning, the immature eagle followed the narrow flightpath through Africa used by other Lesser Spotted Eagles on their outward migration. It reached this corridor, which runs roughly between longitudes 31? and 36? East from Suez to Lake Tanganyika, veering from the shortest route in a direction east-northeast through Angola and Zambia to the southern end of Lake Tanganyika. The route taken by the subadult bird on its return migration differed markedly from that of all Lesser Spotted Eagles tracked to date, running further west through the Democratic Republic of Congo where, level with the equator, it flew over the eastern rainforest of that country. The outward migration, however, followed the same corridor and coincided in time with the migration of adults.

  6. Glycation of extracellular matrix proteins impairs migration of immune cells.

    Science.gov (United States)

    Haucke, Elisa; Navarrete-Santos, Alexander; Simm, Andreas; Silber, Rolf-Edgar; Hofmann, Britt

    2014-01-01

    The immune response during aging and diabetes is disturbed and may be due to the altered migration of immune cells in an aged tissue. Our study should prove the hypothesis that age and diabetes-related advanced glycation end products (AGEs) have an impact on the migration and adhesion of human T-cells. To achieve our purpose, we used in vitro AGE-modified proteins (soluble albumin and fibronectin [FN]), as well as human collagen obtained from bypass graft. A Boyden chamber was used to study cell migration. Migrated Jurkat T-cells were analyzed by flow cytometry and cell adhesion by crystal violet staining. Actin polymerization was determined by phalloidin-Alexa-fluor 488-labeled antibody and fluorescence microscopy. We found that significantly fewer cells (50%, p = 0.003) migrated through methylglyoxal modified FN. The attachment to FN in the presence of AGE-bovine serum albumin (BSA) was also reduced (p < 0.05). In ex vivo experiments, isolated collagen from human vein graft material negatively affected the migration of the cells depending on the grade of AGE modification of the collagen. Collagen with a low AGE level reduced the cell migration by 30%, and collagen with a high AGE level by 60%. Interaction of the cells with an AGE-modified matrix, but not with soluble AGEs like BSA-AGE per se, was responsible for a disturbed migration. The reduced migration was accompanied by an impaired actin polymerization. We conclude that AGEs-modified matrix protein inhibits cell migration and adhesion of Jurkat T-cells.

  7. Automated migration analysis based on cell texture: method & reliability

    Directory of Open Access Journals (Sweden)

    Chittenden Thomas W

    2005-03-01

    Full Text Available Abstract Background In this paper, we present and validate a way to measure automatically the extent of cell migration based on automated examination of a series of digital photographs. It was designed specifically to identify the impact of Second Hand Smoke (SHS on endothelial cell migration but has broader applications. The analysis has two stages: (1 preprocessing of image texture, and (2 migration analysis. Results The output is a graphic overlay that indicates the front lines of cell migration superimposed on each original image, with automated reporting of the distance traversed vs. time. Expert preference compares to manual placement of leading edge shows complete equivalence of automated vs. manual leading edge definition for cell migration measurement. Conclusion Our method is indistinguishable from careful manual determinations of cell front lines, with the advantages of full automation, objectivity, and speed.

  8. Phenotypic changes in satellite glial cells in cultured trigeminal ganglia.

    Science.gov (United States)

    Belzer, Vitali; Shraer, Nathanael; Hanani, Menachem

    2010-11-01

    Satellite glial cells (SGCs) are specialized cells that form a tight sheath around neurons in sensory ganglia. In recent years, there is increasing interest in SGCs and they have been studied in both intact ganglia and in tissue culture. Here we studied phenotypic changes in SGCs in cultured trigeminal ganglia from adult mice, containing both neurons and SGCs, using phase optics, immunohistochemistry and time-lapse photography. Cultures were followed for up to 14 days. After isolation virtually every sensory neuron is ensheathed by SGCs, as in the intact ganglia. After one day in culture, SGCs begin to migrate away from their parent neurons, but in most cases the neurons still retain an intact glial cover. At later times in culture, there is a massive migration of SGCs away from the neurons and they undergo clear morphological changes, and at 7 days they become spindle-shaped. At one day in culture SGCs express the glial marker glutamine synthetase, and also the purinergic receptor P2X7. From day 2 in culture the glutamine synthetase expression is greatly diminished, whereas that of P2X7 is largely unchanged. We conclude that SGCs retain most of their characteristics for about 24 h after culturing, but undergo major phenotypic changes at later times.

  9. Collective dynamics of cell migration and cell rearrangements

    Science.gov (United States)

    Kabla, Alexandre

    Understanding multicellular processes such as embryo development or cancer metastasis requires to decipher the contributions of local cell autonomous behaviours and long range interactions with the tissue environment. A key question in this context concerns the emergence of large scale coordination in cell behaviours, a requirement for collective cell migration or convergent extension. I will present a few examples where physical and mechanical aspects play a significant role in driving tissue scale dynamics. Geometrical confinement is one of the key external factors influencing large scale coordination during collective migration. Using a combination of in vitro experiments and numerical simulations, we show that the velocity correlation length, measured in unconfined conditions, provides a convenient length scale to predict the dynamic response under confinement. The same length scale can also be used to quantify the influence range of directional cues within the cell population. Heterogeneity within motile cell populations is frequently associated with an increase in their invasive capability and appears to play an important role during cancer metastasis. Using in silico experiments, we studied the way cell invasion is influenced by both the degree of cell coordination and the amount of variability in the motile force of the invading cells. Results suggest that mechanical heterogeneity dramatically enhances the invasion rate through an emerging cooperative process between the stronger and weaker cells, accounting for a number of observed invasion phenotypes. Effective convergent extension requires on a consistent orientation of cell intercalation at the tissue scale, most often in relation with planar cell polarity mechanisms to define the primary axes of deformation. Using a novel modelling approach for cells mechanical interactions, we studied the dynamics of substrate free motile cell populations. Ongoing work shows in particular that nematic order emerges

  10. Functional transcriptomics of a migrating cell in Caenorhabditis elegans.

    Science.gov (United States)

    Schwarz, Erich M; Kato, Mihoko; Sternberg, Paul W

    2012-10-02

    In both metazoan development and metastatic cancer, migrating cells must carry out a detailed, complex program of sensing cues, binding substrates, and moving their cytoskeletons. The linker cell in Caenorhabditis elegans males undergoes a stereotyped migration that guides gonad organogenesis, occurs with precise timing, and requires the nuclear hormone receptor NHR-67. To better understand how this occurs, we performed RNA-seq of individually staged and dissected linker cells, comparing transcriptomes from linker cells of third-stage (L3) larvae, fourth-stage (L4) larvae, and nhr-67-RNAi-treated L4 larvae. We observed expression of 8,000-10,000 genes in the linker cell, 22-25% of which were up- or down-regulated 20-fold during development by NHR-67. Of genes that we tested by RNAi, 22% (45 of 204) were required for normal shape and migration, suggesting that many NHR-67-dependent, linker cell-enriched genes play roles in this migration. One unexpected class of genes up-regulated by NHR-67 was tandem pore potassium channels, which are required for normal linker-cell migration. We also found phenotypes for genes with human orthologs but no previously described migratory function. Our results provide an extensive catalog of genes that act in a migrating cell, identify unique molecular functions involved in nematode cell migration, and suggest similar functions in humans.

  11. Asymmetric division coordinates collective cell migration in angiogenesis.

    Science.gov (United States)

    Costa, Guilherme; Harrington, Kyle I; Lovegrove, Holly E; Page, Donna J; Chakravartula, Shilpa; Bentley, Katie; Herbert, Shane P

    2016-12-01

    The asymmetric division of stem or progenitor cells generates daughters with distinct fates and regulates cell diversity during tissue morphogenesis. However, roles for asymmetric division in other more dynamic morphogenetic processes, such as cell migration, have not previously been described. Here we combine zebrafish in vivo experimental and computational approaches to reveal that heterogeneity introduced by asymmetric division generates multicellular polarity that drives coordinated collective cell migration in angiogenesis. We find that asymmetric positioning of the mitotic spindle during endothelial tip cell division generates daughters of distinct size with discrete 'tip' or 'stalk' thresholds of pro-migratory Vegfr signalling. Consequently, post-mitotic Vegfr asymmetry drives Dll4/Notch-independent self-organization of daughters into leading tip or trailing stalk cells, and disruption of asymmetry randomizes daughter tip/stalk selection. Thus, asymmetric division seamlessly integrates cell proliferation with collective migration, and, as such, may facilitate growth of other collectively migrating tissues during development, regeneration and cancer invasion.

  12. Silk film topography directs collective epithelial cell migration.

    Directory of Open Access Journals (Sweden)

    Brian D Lawrence

    Full Text Available The following study provides new insight into how surface topography dictates directed collective epithelial cell sheet growth through the guidance of individual cell movement. Collective cell behavior of migrating human corneal limbal-epithelial cell sheets were studied on highly biocompatible flat and micro-patterned silk film surfaces. The silk film edge topography guided the migratory direction of individual cells making up the collective epithelial sheet, which resulted in a 75% increase in total culture elongation. This was due to a 3-fold decrease in cell sheet migration rate efficiency for movement perpendicular to the topography edge. Individual cell migration direction is preferred in the parallel approach to the edge topography where localization of cytoskeletal proteins to the topography's edge region is reduced, which results in the directed growth of the collective epithelial sheet. Findings indicate customized biomaterial surfaces may be created to direct both the migration rate and direction of tissue epithelialization.

  13. Cancer cell motility: lessons from migration in confined spaces

    Science.gov (United States)

    Paul, Colin D.; Mistriotis, Panagiotis; Konstantopoulos, Konstantinos

    2017-01-01

    Time-lapse, deep-tissue imaging made possible by advances in intravital microscopy has demonstrated the importance of tumour cell migration through confining tracks in vivo. These tracks may either be endogenous features of tissues or be created by tumour or tumour-associated cells. Importantly, migration mechanisms through confining microenvironments are not predicted by 2D migration assays. Engineered in vitro models have been used to delineate the mechanisms of cell motility through confining spaces encountered in vivo. Understanding cancer cell locomotion through physiologically relevant confining tracks could be useful in developing therapeutic strategies to combat metastasis. PMID:27909339

  14. Collective cell migration drives morphogenesis of the kidney nephron.

    Directory of Open Access Journals (Sweden)

    Aleksandr Vasilyev

    2009-01-01

    Full Text Available Tissue organization in epithelial organs is achieved during development by the combined processes of cell differentiation and morphogenetic cell movements. In the kidney, the nephron is the functional organ unit. Each nephron is an epithelial tubule that is subdivided into discrete segments with specific transport functions. Little is known about how nephron segments are defined or how segments acquire their distinctive morphology and cell shape. Using live, in vivo cell imaging of the forming zebrafish pronephric nephron, we found that the migration of fully differentiated epithelial cells accounts for both the final position of nephron segment boundaries and the characteristic convolution of the proximal tubule. Pronephric cells maintain adherens junctions and polarized apical brush border membranes while they migrate collectively. Individual tubule cells exhibit basal membrane protrusions in the direction of movement and appear to establish transient, phosphorylated Focal Adhesion Kinase-positive adhesions to the basement membrane. Cell migration continued in the presence of camptothecin, indicating that cell division does not drive migration. Lengthening of the nephron was, however, accompanied by an increase in tubule cell number, specifically in the most distal, ret1-positive nephron segment. The initiation of cell migration coincided with the onset of fluid flow in the pronephros. Complete blockade of pronephric fluid flow prevented cell migration and proximal nephron convolution. Selective blockade of proximal, filtration-driven fluid flow shifted the position of tubule convolution distally and revealed a role for cilia-driven fluid flow in persistent migration of distal nephron cells. We conclude that nephron morphogenesis is driven by fluid flow-dependent, collective epithelial cell migration within the confines of the tubule basement membrane. Our results establish intimate links between nephron function, fluid flow, and morphogenesis.

  15. Satellite Cells in Muscular Dystrophy - Lost in Polarity.

    Science.gov (United States)

    Chang, Natasha C; Chevalier, Fabien P; Rudnicki, Michael A

    2016-06-01

    Recent findings employing the mdx mouse model for Duchenne muscular dystrophy (DMD) have revealed that muscle satellite stem cells play a direct role in contributing to disease etiology and progression of DMD, the most common and severe form of muscular dystrophy. Lack of dystrophin expression in DMD has critical consequences in satellite cells including an inability to establish cell polarity, abrogation of asymmetric satellite stem-cell divisions, and failure to enter the myogenic program. Thus, muscle wasting in dystrophic mice is not only caused by myofiber fragility but is exacerbated by intrinsic satellite cell dysfunction leading to impaired regeneration. Despite intense research and clinical efforts, there is still no effective cure for DMD. In this review we highlight recent research advances in DMD and discuss the current state of treatment and, importantly, how we can incorporate satellite cell-targeted therapeutic strategies to correct satellite cell dysfunction in DMD.

  16. Myogenic skeletal muscle satellite cells communicate by tunnelling nanotubes.

    Science.gov (United States)

    Tavi, Pasi; Korhonen, Topi; Hänninen, Sandra L; Bruton, Joseph D; Lööf, Sara; Simon, Andras; Westerblad, Håkan

    2010-05-01

    Quiescent satellite cells sit on the surface of the muscle fibres under the basal lamina and are activated by a variety of stimuli to disengage, divide and differentiate into myoblasts that can regenerate or repair muscle fibres. Satellite cells adopt their parent's fibre type and must have some means of communication with the parent fibre. The mechanisms behind this communication are not known. We show here that satellite cells form dynamic connections with muscle fibres and other satellite cells by F-actin based tunnelling nanotubes (TNTs). Our results show that TNTs readily develop between satellite cells and muscle fibres. Once developed, TNTs permit transport of intracellular material, and even cellular organelles such as mitochondria between the muscle fibre and satellite cells. The onset of satellite cell differentiation markers Pax-7 and MyoD expression was slower in satellite cells cultured in the absence than in the presence of muscle cells. Furthermore physical contact between myofibre and satellite cell progeny is required to maintain subtype identity. Our data establish that TNTs constitute an integral part of myogenic cell communication and that physical cellular interaction control myogenic cell fate determination.

  17. Regulator of calcineurin 1 modulates cancer cell migration in vitro

    OpenAIRE

    Espinosa, Allan V.; Shinohara, Motoo; Porchia,Leonardo M; Chung, Yun Jae; McCarty, Samantha; Saji, Motoyasu; Ringel, Matthew D.

    2009-01-01

    Metastasis suppressors and other regulators of cell motility play an important role in tumor invasion and metastases. We previously identified that activation of the G protein coupled receptor 54 (GPR54) by the metastasis suppressor metastin inhibits cell migration in association with overexpression of Regulator of calcineurin 1 (RCAN1), an endogenous regulator of calcineurin. Calcineurin inhibitors also blocked cell migration in vitro and RCAN1 protein levels were reduced in nodal metastases...

  18. Nuclear stiffening inhibits migration of invasive melanoma cells

    OpenAIRE

    Ribeiro, Alexandre J. S.; Khanna, Payal; Sukumar, Aishwarya; Dong, Cheng; Dahl, Kris Noel

    2014-01-01

    During metastasis, melanoma cells must be sufficiently deformable to squeeze through extracellular barriers with small pore sizes. We visualize and quantify deformability of single cells using micropipette aspiration and examine the migration potential of a population of melanoma cells using a flow migration apparatus. We artificially stiffen the nucleus with recombinant overexpression of Δ50 lamin A, which is found in patients with Hutchison Gilford progeria syndrome and in aged individuals....

  19. Migration of dendritic cell based cancer vaccines: in vivo veritas?

    NARCIS (Netherlands)

    Adema, G.J.; Vries, I.J.M. de; Punt, C.J.A.; Figdor, C.G.

    2005-01-01

    Ex vivo generated cancer vaccines based on dendritic cells (DCs) are currently applied in the clinic. The migration of DCs from the tissues to the lymph nodes is tightly controlled and involves many different mediators and their receptors. A recent study demonstrated that the rate of migration of

  20. Analysis of primary cilia in directional cell migration in fibroblasts

    DEFF Research Database (Denmark)

    Christensen, Søren Tvorup; Veland, Iben; Schwab, Albrecht;

    2013-01-01

    Early studies of migrating fibroblasts showed that primary cilia orient in front of the nucleus and point toward the leading edge. Recent work has shown that primary cilia coordinate a series of signaling pathways critical to fibroblast cell migration during development and in wound healing. In p...

  1. A pilgrim's progress: Seeking meaning in primordial germ cell migration.

    Science.gov (United States)

    Cantú, Andrea V; Laird, Diana J

    2017-07-18

    Comparative studies of primordial germ cell (PGC) development across organisms in many phyla reveal surprising diversity in the route of migration, timing and underlying molecular mechanisms, suggesting that the process of migration itself is conserved. However, beyond the perfunctory transport of cellular precursors to their later arising home of the gonads, does PGC migration serve a function? Here we propose that the process of migration plays an additional role in quality control, by eliminating PGCs incapable of completing migration as well as through mechanisms that favor PGCs capable of responding appropriately to migration cues. Focusing on PGCs in mice, we explore evidence for a selective capacity of migration, considering the tandem regulation of proliferation and migration, cell-intrinsic and extrinsic control, the potential for tumors derived from failed PGC migrants, the potential mechanisms by which migratory PGCs vary in their cellular behaviors, and corresponding effects on development. We discuss the implications of a selective role of PGC migration for in vitro gametogenesis. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  2. The histone demethylase UTX regulates stem cell migration and hematopoiesis.

    Science.gov (United States)

    Thieme, Sebastian; Gyárfás, Tobias; Richter, Cornelia; Özhan, Günes; Fu, Jun; Alexopoulou, Dimitra; Muders, Michael H; Michalk, Irene; Jakob, Christiane; Dahl, Andreas; Klink, Barbara; Bandola, Joanna; Bachmann, Michael; Schröck, Evelin; Buchholz, Frank; Stewart, A Francis; Weidinger, Gilbert; Anastassiadis, Konstantinos; Brenner, Sebastian

    2013-03-28

    Regulated migration of hematopoietic stem cells is fundamental for hematopoiesis. The molecular mechanisms underlying stem cell trafficking are poorly defined. Based on a short hairpin RNA library and stromal cell-derived factor-1 (SDF-1) migration screening assay, we identified the histone 3 lysine 27 demethylase UTX (Kdm6a) as a novel regulator for hematopoietic cell migration. Using hematopoietic stem and progenitor cells from our conditional UTX knockout (KO) mice, we were able to confirm the regulatory function of UTX on cell migration. Moreover, adult female conditional UTX KO mice displayed myelodysplasia and splenic erythropoiesis, whereas UTX KO males showed no phenotype. During development, all UTX KO female and a portion of UTX KO male embryos developed a cardiac defect, cranioschisis, and died in utero. Therefore, UTY, the male homolog of UTX, can compensate for UTX in adults and partially during development. Additionally, we found that UTX knockdown in zebrafish significantly impairs SDF-1/CXCR4-dependent migration of primordial germ cells. Our data suggest that UTX is a critical regulator for stem cell migration and hematopoiesis.

  3. Migration

    NARCIS (Netherlands)

    Gienapp, P.; Candolin, Ulrika; Wong, Bob

    2012-01-01

    This chapter examines how human-induced environmental changes affect migration. It explores how such changes affect conditions along the migration route, as well as the cues that are used in the timing of migration such as the celestial bodies and the planet's magnetic field. It emphasizes the effec

  4. The thioredoxin system in breast cancer cell invasion and migration

    Directory of Open Access Journals (Sweden)

    Maneet Bhatia

    2016-08-01

    Full Text Available Metastasis is the most life threatening aspect of breast cancer. It is a multi-step process involving invasion and migration of primary tumor cells with a subsequent colonization of these cells at a secondary location. The aim of the present study was to investigate the role of thioredoxin (Trx1 in the invasion and migration of breast cancer cells and to assess the strength of the association between high levels of Trx1 and thioredoxin reductase (TrxR1 expression with breast cancer patient survival. Our results indicate that the expression of both Trx1 and TrxR1 are statistically significantly increased in breast cancer patient cells compared with paired normal breast tissue from the same patient. Over-expression of Trx1 in MDA-MB-231 breast cancer cell lines enhanced cell invasion in in vitro assays while expression of a redox inactive mutant form of Trx1 (designated 1SS or the antisense mRNA inhibited cell invasion. Addition of exogenous Trx1 also enhanced cell invasion, while addition of a specific monoclonal antibody that inhibits Trx1 redox function decreased cell invasion. Over-expression of intracellular Trx1 did not increase cell migration but expression of intracellular 1SS inhibited migration. Addition of exogenous Trx1 enhanced cell migration while 1SS had no effect. Treatment with auranofin inhibited TrxR activity, cell migration and clonogenic activity of MDA-MB-231 cells, while increasing reactive oxygen species (ROS levels. Analysis of 25 independent cohorts with 5910 patients showed that Trx1 and TrxR1 were both associated with a poor patient prognosis in terms of overall survival, distant metastasis free survival and disease free survival. Therefore, targeting the Trx system with auranofin or other specific inhibitors may provide improved breast cancer patient outcomes through inhibition of cancer invasion and migration.

  5. The thioredoxin system in breast cancer cell invasion and migration.

    Science.gov (United States)

    Bhatia, Maneet; McGrath, Kelly L; Di Trapani, Giovanna; Charoentong, Pornpimol; Shah, Fenil; King, Mallory M; Clarke, Frank M; Tonissen, Kathryn F

    2016-08-01

    Metastasis is the most life threatening aspect of breast cancer. It is a multi-step process involving invasion and migration of primary tumor cells with a subsequent colonization of these cells at a secondary location. The aim of the present study was to investigate the role of thioredoxin (Trx1) in the invasion and migration of breast cancer cells and to assess the strength of the association between high levels of Trx1 and thioredoxin reductase (TrxR1) expression with breast cancer patient survival. Our results indicate that the expression of both Trx1 and TrxR1 are statistically significantly increased in breast cancer patient cells compared with paired normal breast tissue from the same patient. Over-expression of Trx1 in MDA-MB-231 breast cancer cell lines enhanced cell invasion in in vitro assays while expression of a redox inactive mutant form of Trx1 (designated 1SS) or the antisense mRNA inhibited cell invasion. Addition of exogenous Trx1 also enhanced cell invasion, while addition of a specific monoclonal antibody that inhibits Trx1 redox function decreased cell invasion. Over-expression of intracellular Trx1 did not increase cell migration but expression of intracellular 1SS inhibited migration. Addition of exogenous Trx1 enhanced cell migration while 1SS had no effect. Treatment with auranofin inhibited TrxR activity, cell migration and clonogenic activity of MDA-MB-231 cells, while increasing reactive oxygen species (ROS) levels. Analysis of 25 independent cohorts with 5910 patients showed that Trx1 and TrxR1 were both associated with a poor patient prognosis in terms of overall survival, distant metastasis free survival and disease free survival. Therefore, targeting the Trx system with auranofin or other specific inhibitors may provide improved breast cancer patient outcomes through inhibition of cancer invasion and migration.

  6. Patterned hybrid nanohole array surfaces for cell adhesion and migration.

    Science.gov (United States)

    Westcott, Nathan P; Lou, Yi; Muth, John F; Yousaf, Muhammad N

    2009-10-06

    We report the fabrication of hybrid nanohole array surfaces to study the role of the surface nanoevironment on cell adhesion and cell migration. We use polystyrene beads and reactive ion etching to control the size and the spacing between nanoholes on a tailored self-assembled monolayer inert gold surface. The arrays were characterized by scanning electron microscopy and brightfield microscopy. For cell adhesion studies, cells were seeded to these substrates to study the effect of ligand spacing on cell spreading, stress fiber formation, and focal adhesion structure and size. Finally, comparative cell migration rates were examined on the various nanohole array surfaces using time-lapse microscopy.

  7. An open data ecosystem for cell migration research

    NARCIS (Netherlands)

    Masuzzo, P.; Martens, L.; Ampe, C.; Anderson, K.I.; Barry, J.; Wever, O. De; Debeir, O.; Decaestecker, C.; Dolznig, H.; Friedl, P.H.A.; Gaggioli, C.; Geiger, B.; Goldberg, I.G.; Horn, E.; Horwitz, R.; Kam, Z.; Devedec, S.E. Le; Vignjevic, D.M.; Moore, J.; Olivo-Marin, J.C.; Sahai, E.; Sansone, S.A.; Sanz-Moreno, V.; Stromblad, S.; Swedlow, J.; Textor, J.C.; Troys, M. Van; Zantl, R.

    2015-01-01

    Cell migration research has recently become both a high content and a high throughput field thanks to technological, computational, and methodological advances. Simultaneously, however, urgent bioinformatics needs regarding data management, standardization, and dissemination have emerged. To address

  8. An open data ecosystem for cell migration research

    NARCIS (Netherlands)

    Masuzzo, P.; Martens, L.; Ampe, C.; Anderson, K.I.; Barry, J.; Wever, O. De; Debeir, O.; Decaestecker, C.; Dolznig, H.; Friedl, P.H.A.; Gaggioli, C.; Geiger, B.; Goldberg, I.G.; Horn, E.; Horwitz, R.; Kam, Z.; Devedec, S.E. Le; Vignjevic, D.M.; Moore, J.; Olivo-Marin, J.C.; Sahai, E.; Sansone, S.A.; Sanz-Moreno, V.; Stromblad, S.; Swedlow, J.; Textor, J.C.; Troys, M. Van; Zantl, R.

    2015-01-01

    Cell migration research has recently become both a high content and a high throughput field thanks to technological, computational, and methodological advances. Simultaneously, however, urgent bioinformatics needs regarding data management, standardization, and dissemination have emerged. To address

  9. Long-Term Live Cell Imaging of Cell Migration: Effects of Pathogenic Fungi on Human Epithelial Cell Migration.

    Science.gov (United States)

    Wöllert, Torsten; Langford, George M

    2016-01-01

    Long-term live cell imaging was used in this study to determine the responses of human epithelial cells to pathogenic biofilms formed by Candida albicans. Epithelial cells of the skin represent the front line of defense against invasive pathogens such as C. albicans but under certain circumstances, especially when the host's immune system is compromised, the skin barrier is breached. The mechanisms by which the fungal pathogen penetrates the skin and invade the deeper layers are not fully understood. In this study we used keratinocytes grown in culture as an in vitro model system to determine changes in host cell migration and the actin cytoskeleton in response to virulence factors produced by biofilms of pathogenic C. albicans. It is clear that changes in epithelial cell migration are part of the response to virulence factors secreted by biofilms of C. albicans and the actin cytoskeleton is the downstream effector that mediates cell migration. Our goal is to understand the mechanism by which virulence factors hijack the signaling pathways of the actin cytoskeleton to alter cell migration and thereby invade host tissues. To understand the dynamic changes of the actin cytoskeleton during infection, we used long-term live cell imaging to obtain spatial and temporal information of actin filament dynamics and to identify signal transduction pathways that regulate the actin cytoskeleton and its associated proteins. Long-term live cell imaging was achieved using a high resolution, multi-mode epifluorescence microscope equipped with specialized light sources, high-speed cameras with high sensitivity detectors, and specific biocompatible fluorescent markers. In addition to the multi-mode epifluorescence microscope, a spinning disk confocal long-term live cell imaging system (Olympus CV1000) equipped with a stage incubator to create a stable in vitro environment for long-term real-time and time-lapse microscopy was used. Detailed descriptions of these two long-term live

  10. Migration of epithelial cells on laminins: RhoA antagonizes directionally persistent migration.

    Science.gov (United States)

    Zhang, Zhigang; Chometon, Gretel; Wen, Tingting; Qu, Haiyan; Mauch, Cornelia; Krieg, Thomas; Aumailley, Monique

    2011-01-01

    Spatial and temporal expression of laminin isoforms is assumed to provide specific local information to neighboring cells. Here, we report the remarkably selective presence of LM-111 at the very tip of hair follicles where LM-332 is absent, suggesting that epithelial cells lining the dermal-epidermal junction at this location may receive different signals from the two laminins. This hypothesis was tested in vitro by characterizing with functional and molecular assays the comportment of keratinocytes exposed to LM-111 and LM-332. The two laminins induced morphologically distinct focal adhesions, and LM-332, but not LM-111, elicited persistent migration of keratinocytes. The different impact on cellular behavior was associated with distinct activation patterns of Rho GTPases and other signaling intermediates. In particular, while LM-111 triggered a robust activation of Cdc42, LM-332 provoked a strong and sustained activation of FAK. Interestingly, activation of Rac1 was necessary but not sufficient to promote migration because there was no directed migration on LM-111 despite Rac1 activation. In contrast, RhoA antagonized directional migration, since silencing of RhoA by RNA interference boosted unidirectional migration on LM-332. Molecular analysis of the role of RhoA strongly suggested that the mechanisms involve disassembly of cell-cell contacts, loss of the cortical actin network, mobilization of α6β4 integrin out of stable adhesions, and displacement of the integrin from its association with the insoluble pool of intermediate filaments.

  11. Phosphorylation of actopaxin regulates cell spreading and migration

    Science.gov (United States)

    Clarke, Dominic M.; Brown, Michael C.; LaLonde, David P.; Turner, Christopher E.

    2004-01-01

    Actopaxin is an actin and paxillin binding protein that localizes to focal adhesions. It regulates cell spreading and is phosphorylated during mitosis. Herein, we identify a role for actopaxin phosphorylation in cell spreading and migration. Stable clones of U2OS cells expressing actopaxin wild-type (WT), nonphosphorylatable, and phosphomimetic mutants were developed to evaluate actopaxin function. All proteins targeted to focal adhesions, however the nonphosphorylatable mutant inhibited spreading whereas the phosphomimetic mutant cells spread more efficiently than WT cells. Endogenous and WT actopaxin, but not the nonphosphorylatable mutant, were phosphorylated in vivo during cell adhesion/spreading. Expression of the nonphosphorylatable actopaxin mutant significantly reduced cell migration, whereas expression of the phosphomimetic increased cell migration in scrape wound and Boyden chamber migration assays. In vitro kinase assays demonstrate that extracellular signal-regulated protein kinase phosphorylates actopaxin, and treatment of U2OS cells with the MEK1 inhibitor UO126 inhibited adhesion-induced phosphorylation of actopaxin and also inhibited cell migration. PMID:15353548

  12. SOX15 regulates proliferation and migration of endometrial cancer cells.

    Science.gov (United States)

    Rui, Xiaohui; Xu, Yun; Jiang, Xiping; Guo, Caixia; Jiang, Jingting

    2017-08-18

    The study aimed to investigate the effects of SOX15 on proliferation and migration of endometrial cancer (EC) cells. Immunohistochemistry was applied to determine the expression of SOX15 in EC tissues and adjacent tissues. We used cell transfection method to construct the HEC-1-A and Ishikawa cell lines with stable overexpression and low-expression SOX15 Reverse transcription quantitative real-time PCR (RT-qPCR) and western blot were performed to examine expression of SOX15 mRNA and SOX15 protein respectively. By conducting a series of cell proliferation assay and migration assay, we analyzed the influence of SOX15 overexpression or low-expression on EC cell proliferation and migration. The expression of SOX15 mRNA and protein in EC tissues was significantly lower than that in adjacent tissues. After lentivirus-transfecting SOX15 , the expression level of SOX15 mRNA and protein was significantly increased in cells of SOX15 group, and decreased in sh- SOX15 group. Overexpression of SOX15 could suppress cell proliferation, while downregulation of SOX15 increased cell proliferation. Flow cytometry results indicated that overexpression of SOX15 induced the ratio of cell cycle arrest in G1 stage. In addition, transwell migration assay results showed that SOX15 overexpression significantly inhibited cell migration, and also downregulation of SOX15 promoted the migration. As a whole, SOX15 could regulate the proliferation and migration of EC cells and upregulation of SOX15 could be valuable for EC treatment. ©2017 The Author(s).

  13. Functional Overload Enhances Satellite Cell Properties in Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Shin Fujimaki

    2016-01-01

    Full Text Available Skeletal muscle represents a plentiful and accessible source of adult stem cells. Skeletal-muscle-derived stem cells, termed satellite cells, play essential roles in postnatal growth, maintenance, repair, and regeneration of skeletal muscle. Although it is well known that the number of satellite cells increases following physical exercise, functional alterations in satellite cells such as proliferative capacity and differentiation efficiency following exercise and their molecular mechanisms remain unclear. Here, we found that functional overload, which is widely used to model resistance exercise, causes skeletal muscle hypertrophy and converts satellite cells from quiescent state to activated state. Our analysis showed that functional overload induces the expression of MyoD in satellite cells and enhances the proliferative capacity and differentiation potential of these cells. The changes in satellite cell properties coincided with the inactivation of Notch signaling and the activation of Wnt signaling and likely involve modulation by transcription factors of the Sox family. These results indicate the effects of resistance exercise on the regulation of satellite cells and provide insight into the molecular mechanism of satellite cell activation following physical exercise.

  14. Isolation, Culture and Identification of Porcine Skeletal Muscle Satellite Cells

    Directory of Open Access Journals (Sweden)

    Bo-jiang Li

    2015-08-01

    Full Text Available The objective of this study was to establish the optimum protocol for the isolation and culture of porcine muscle satellite cells. Mononuclear muscle satellite cells are a kind of adult stem cell, which is located between the basal lamina and sarcolemma of muscle fibers and is the primary source of myogenic precursor cells in postnatal muscle. Muscle satellite cells are a useful model to investigate the mechanisms of muscle growth and development. Although the isolation and culture protocols of muscle satellite cells in some species (e.g. mouse have been established successfully, the culture system for porcine muscle satellite cells is very limited. In this study, we optimized the isolation procedure of porcine muscle satellite cells and elaborated the isolation and culture process in detail. Furthermore, we characterized the porcine muscle satellite cells using the immunofluorecence. Our study provides a reference for the isolation of porcine muscle satellite cells and will be useful for studying the molecular mechanisms in these cells.

  15. Annexin A1 induces skeletal muscle cell migration acting through formyl peptide receptors.

    Directory of Open Access Journals (Sweden)

    Valentina Bizzarro

    Full Text Available Annexin A1 (ANXA1, lipocortin-1 is a glucocorticoid-regulated 37-kDa protein, so called since its main property is to bind (i.e. to annex to cellular membranes in a Ca(2+-dependent manner. Although ANXA1 has predominantly been studied in the context of immune responses and cancer, the protein can affect a larger variety of biological phenomena, including cell proliferation and migration. Our previous results show that endogenous ANXA1 positively modulates myoblast cell differentiation by promoting migration of satellite cells and, consequently, skeletal muscle differentiation. In this work, we have evaluated the hypothesis that ANXA1 is able to exert effects on myoblast cell migration acting through formyl peptide receptors (FPRs following changes in its subcellular localization as in other cell types and tissues. The analysis of the subcellular localization of ANXA1 in C2C12 myoblasts during myogenic differentiation showed an interesting increase of extracellular ANXA1 starting from the initial phases of skeletal muscle cell differentiation. The investigation of intracellular Ca(2+ perturbation following exogenous administration of the ANXA1 N-terminal derived peptide Ac2-26 established the engagement of the FPRs which expression in C2C12 cells was assessed by qualitative PCR. Wound healing assay experiments showed that Ac2-26 peptide is able to increase migration of C2C12 skeletal muscle cells and to induce cell surface translocation and secretion of ANXA1. Our results suggest a role for ANXA1 as a highly versatile component in the signaling chains triggered by the proper calcium perturbation that takes place during active migration and differentiation or membrane repair since the protein is strongly redistributed onto the plasma membranes after an rapid increase of intracellular levels of Ca(2+. These properties indicate that ANXA1 may be involved in a novel repair mechanism for skeletal muscle and may have therapeutic implications with

  16. 3D printing of biomimetic microstructures for cancer cell migration

    Science.gov (United States)

    Huang, Tina Qing; Qu, Xin; Liu, Justin; Chen, Shaochen

    2013-01-01

    To understand the physical behavior and migration of cancer cells, a 3D in vitro micro-chip in hydrogel was created using 3D projection printing. The micro-chip has a honeycomb branched structure, aiming to mimic 3D vascular morphology to test, monitor, and analyze differences in the behavior of cancer cells (i.e. HeLa) vs. non-cancerous cell lines (i.e. 10T1/2). The 3D Projection Printing system can fabricate complex structures in seconds from user-created designs. The fabricated microstructures have three different channel widths of 25, 45, and 120 microns wide to reflect a range of blood vessel diameters. HeLa and 10T1/2 cells seeded within the micro-chip were then analyzed for morphology and cell migration speed. 10T1/2 cells exhibited greater changes in morphology due to channel size width than HeLa cells; however, channel width had a limited effect on 10T1/2 cell migration while HeLa cancer cell migration increased as channel width decreased. This physiologically relevant 3D cancer tissue model has the potential to be a powerful tool for future drug discoveries and cancer migration studies PMID:24150602

  17. Satellite cells from dystrophic muscle retain regenerative capacity

    Directory of Open Access Journals (Sweden)

    Luisa Boldrin

    2015-01-01

    Full Text Available Duchenne muscular dystrophy is an inherited disorder that is characterized by progressive skeletal muscle weakness and wasting, with a failure of muscle maintenance/repair mediated by satellite cells (muscle stem cells. The function of skeletal muscle stem cells resident in dystrophic muscle may be perturbed by being in an increasing pathogenic environment, coupled with constant demands for repairing muscle. To investigate the contribution of satellite cell exhaustion to this process, we tested the functionality of satellite cells isolated from the mdx mouse model of Duchenne muscular dystrophy. We found that satellite cells derived from young mdx mice contributed efficiently to muscle regeneration within our in vivo mouse model. To then test the effects of long-term residence in a dystrophic environment, satellite cells were isolated from aged mdx muscle. Surprisingly, they were as functional as those derived from young or aged wild type donors. Removing satellite cells from a dystrophic milieu reveals that their regenerative capacity remains both intact and similar to satellite cells derived from healthy muscle, indicating that the host environment is critical for controlling satellite cell function.

  18. The role of satellite cells in muscle hypertrophy.

    Science.gov (United States)

    Blaauw, Bert; Reggiani, Carlo

    2014-02-01

    The role of satellite cells in muscle hypertrophy has long been a debated issue. In the late 1980s it was shown that proteins remain close to the myonucleus responsible for its synthesis, giving rise to the idea of a nuclear domain. This, together with the observation that during various models of muscle hypertrophy there is an activation of the muscle stem cells, i.e. satellite cells, lead to the idea that satellite cell activation is required for muscle hypertrophy. Thus, satellite cells are not only responsible for muscle repair and regeneration, but also for hypertrophic growth. Further support for this line of thinking was obtained after studies showing that irradiation of skeletal muscle, and therefore elimination of all satellite cells, completely prevented overload-induced hypertrophy. Recently however, using different transgenic approaches, it has become clear that muscle hypertrophy can occur without a contribution of satellite cells, even though in most situations of muscle hypertrophy satellite cells are activated. In this review we will discuss the contribution of satellite cells, and other muscle-resident stem cells, to muscle hypertrophy both in mice as well as in humans.

  19. Narrow-front loop migration in a population of the common cuckoo Cuculus canorus, as revealed by satellite telemetry.

    Science.gov (United States)

    Willemoes, Mikkel; Strandberg, Roine; Klaassen, Raymond H G; Tøttrup, Anders P; Vardanis, Yannis; Howey, Paul W; Thorup, Kasper; Wikelski, Martin; Alerstam, Thomas

    2014-01-01

    Narrow migration corridors known in diurnal, social migrants such as raptors, storks and geese are thought to be caused by topographical leading line effects in combination with learning detailed routes across generations. Here, we document narrow-front migration in a nocturnal, solitary migrant, the common cuckoo Cuculus canorus, using satellite telemetry. We tracked the migration of adult cuckoos from the breeding grounds in southern Scandinavia (n = 8), to wintering sites in south-western Central Africa (n = 6) and back to the breeding grounds (n = 3). Migration patterns were very complex; in addition to the breeding and wintering sites, six different stopover sites were identified during the 16,000 km annual route that formed a large-scale clockwise loop. Despite this complexity, individuals showed surprisingly similar migration patterns, with very little variation between routes. We compared observed tracks with simulated routes based on vector orientation (with and without effects of barriers on orientation and survival). Observed distances between routes were often significantly smaller than expected if the routes were established on the basis of an innate vector orientation programme. Average distance between individuals in eastern Sahel after having migrated more than 5,000 km for example, was merely 164 km. This implies that more sophisticated inherent guiding mechanisms, possibly involving elements of intermediate goal area navigation or more elaborate external cues, are necessary to explain the complex narrow-front migration pattern observed for the cuckoos in this study.

  20. Narrow-front loop migration in a population of the common cuckoo Cuculus canorus, as revealed by satellite telemetry.

    Directory of Open Access Journals (Sweden)

    Mikkel Willemoes

    Full Text Available Narrow migration corridors known in diurnal, social migrants such as raptors, storks and geese are thought to be caused by topographical leading line effects in combination with learning detailed routes across generations. Here, we document narrow-front migration in a nocturnal, solitary migrant, the common cuckoo Cuculus canorus, using satellite telemetry. We tracked the migration of adult cuckoos from the breeding grounds in southern Scandinavia (n = 8, to wintering sites in south-western Central Africa (n = 6 and back to the breeding grounds (n = 3. Migration patterns were very complex; in addition to the breeding and wintering sites, six different stopover sites were identified during the 16,000 km annual route that formed a large-scale clockwise loop. Despite this complexity, individuals showed surprisingly similar migration patterns, with very little variation between routes. We compared observed tracks with simulated routes based on vector orientation (with and without effects of barriers on orientation and survival. Observed distances between routes were often significantly smaller than expected if the routes were established on the basis of an innate vector orientation programme. Average distance between individuals in eastern Sahel after having migrated more than 5,000 km for example, was merely 164 km. This implies that more sophisticated inherent guiding mechanisms, possibly involving elements of intermediate goal area navigation or more elaborate external cues, are necessary to explain the complex narrow-front migration pattern observed for the cuckoos in this study.

  1. Laser-photophoretic migration and fractionation of human blood cells.

    Science.gov (United States)

    Monjushiro, Hideaki; Tanahashi, Yuko; Watarai, Hitoshi

    2013-05-13

    Laser photophoretic migration behavior of human blood cells in saline solution was investigated under the irradiation of Nd:YAG laser beam (532 nm) in the absence and the presence of the flow in a fused silica capillary. Red blood cells (RBC) were migrated faster than white blood cells (WBC) and blood pellets to the direction of propagation of laser light. The observed photophoretic velocity of RBC was about 11 times faster than those of others. This was understood from the larger photophoretic efficiency of RBC than that of WBC, which was simulated based on the Mie scattering theory. Furthermore, it was found that, during the photophoretic migration, RBCs spontaneously orientated parallel to the migration direction so as to reduce the drag force. Finally, it was demonstrated that RBC and WBC were separated in a micro-channel flow system by the laser photophoresis.

  2. Modelling Rho GTPase biochemistry to predict collective cell migration

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    Merchant, Brian; Feng, James

    The collective migration of cells, due to individual cell polarization and intercellular contact inhibition of locomotion, features prominently in embryogenesis and metastatic cancers. Existing methods for modelling collectively migrating cells tend to rely either on highly abstracted agent-based models, or on continuum approximations of the group. Both of these frameworks represent intercellular interactions such as contact inhibition of locomotion as hard-coded rules defining model cells. In contrast, we present a vertex-dynamics framework which predicts polarization and contact inhibition of locomotion naturally from an underlying model of Rho GTPase biochemistry and cortical mechanics. We simulate the interaction between many such model cells, and study how modulating Rho GTPases affects migratory characteristics of the group, in the context of long-distance collective migration of neural crest cells during embryogenesis.

  3. [Chemokines and their participation in leukemic cells migration].

    Science.gov (United States)

    Parfieńczyk, Adam; Kiersnowska-Rogowska, Beata; Rogowski, Franciszek

    2003-11-01

    Impaired migration of leukocytes is characteristic feature of leukaemias. Knowledge of the mechanisms of leukaemia cells migration has expanded greatly in recent years. Leukocytes infiltrates are formed in surrounding tissues due to changes in chemokines and adhesion molecules concentrations. The adhesive interactions of cells with other cells and between cells and with the extracellular matrix are started by activation leukaemic leukocytes by specific chemokines. There are four groups of chemokines receptors: CXC, CC, C and CX3C. Unfortunately pathological processes of cells activation in the curse of leukaemias have not been fully explained yet. The paper presents current opinions about structure and role of some chemokines and their receptors in leukaemic cells migration.

  4. Commensal bacteria promote migration of mast cells into the intestine.

    Science.gov (United States)

    Kunii, Junichi; Takahashi, Kyoko; Kasakura, Kazumi; Tsuda, Masato; Nakano, Kou; Hosono, Akira; Kaminogawa, Shuichi

    2011-06-01

    Mast cells differentiate from hematopoietic stem cells in the bone marrow and migrate via the circulation to peripheral tissues, where they play a pivotal role in induction of both innate and adaptive immune responses. In this study, the effect of intestinal commensal bacteria on the migration of mast cells into the intestine was investigated. Histochemical analyses showed that germ-free (GF) mice had lower mast cell densities in the small intestine than normal mice. It was also shown that GF mice had lower mast cell proportion out of lamina propria leukocytes in the small intestine and higher mast cell percentages in the blood than normal mice by flow cytometry. These results indicate that migration of mast cells from the blood to the intestine is promoted by intestinal commensal bacteria. In addition, MyD88⁻/⁻ mice had lower densities of intestinal mast cells than CV mice, suggesting that the promotive effect of commensals is, at least in part, TLR-dependent. The ligands of CXC chemokine receptor 2 (CXCR2), which is critical for homing of mast cells to the intestine, were expressed higher in intestinal tissues and in intestinal epithelial cells (IECs) of normal mice than in those of GF or MyD88⁻/⁻ mice. Collectively, it is suggested that commensals promote migration of mast cells into the intestine through the induction of CXCR2 ligands from IECs in a TLR-dependent manner.

  5. Hematopoietic Pyk2 regulates migration of differentiated HL-60 cells

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    Duan Yingli

    2010-05-01

    Full Text Available Abstract Background Pyk2 is a non-receptor cytoplasmic tyrosine kinase that belongs to the focal adhesion kinase family and has been implicated in neutrophil spreading and respiratory burst activity caused by TNF-α. However, the role of Pyk2 in neutrophil migration is incompletely defined. In this study, we tested the hypothesis that Pyk2 regulates the migration of neutrophil-like differentiated HL-60 cells subsequent to β2-integrin mediated cell adhesion. Methods HL-60 cells were induced to differentiate into neutrophil-like cells (dHL60 by incubation in medium containing 1.25% DMSO for up to 4 days. Pyk2 expression and tyrosine phosphorylation was measured by Western blot analysis. Adhesion of dHL60 cells to plated fibrinogen was measured by residual myeloperoxidase activity. dHL60 cell migration was evaluated using a 96-well chemoTx chamber. Results Western blot analysis demonstrated that hematopoietic Pyk2 was predominantly expressed after HL60 cell differentiation. Pyk2 was tyrosine phosphorylated upon adhesion of dHL60 cells to plated fibrinogen in the presence of fMLP. By contrast, tyrosine phosphorylation of Pyk2 was insignificant in dHL60 cells treated in suspension with fMLP. Antibodies against CD18 blocked both phosphorylation of Pyk2 and adhesion of dHL60 cells to fibrinogen, demonstrating that phosphorylation of Pyk2 was β2-integrin dependent. TAT-Pyk2-CT, a dominant negative fusion protein in which the TAT protein transduction domain was fused to the c-terminal Pyk2, attenuated fMLP-stimulated spreading, migration and phosphorylation of endogenous Pyk2 without blocking adhesion of dHL-60 cells to fibrinogen. Similarly, silencing of Pyk2 expression by siRNA in dHL60 cells also attenuated dHL60 cell migration caused by fMLP. Phospho-Pyk2 was evenly distributed around cell membrane circumferentially in unstimulated dHL-60 cells adherent to plated fibrinogen. In dHL60 cells treated with fMLP to cause cell spreading and polarization

  6. Effects of TNF-alpha on Endothelial Cell Collective Migration

    Science.gov (United States)

    Chen, Desu; Wu, Di; Helim Aranda-Espinoza, Jose; Losert, Wolfgang

    2013-03-01

    Tumor necrosis factor (TNF-alpha) is a small cell-signaling protein usually released by monocytes and macrophages during an inflammatory response. Previous work had shown the effects of TNF-alpha on single cell morphology, migration, and biomechanical properties. However, the effect on collective migrations remains unexplored. In this work, we have created scratches on monolayers of human umbilical endothelial cells (HUVECs) treated with 25ng/mL TNF-alpha on glass substrates. The wound healing like processes were imaged with phase contrast microscopy. Quantitative analysis of the collective migration of cells treated with TNF-alpha indicates that these cells maintain their persistent motion and alignment better than untreated cells. In addition, the collective migration was characterized by measuring the amount of non-affine deformations of the wound healing monolayer. We found a lower mean non-affinity and narrower distribution of non-affinities upon TNF-alpha stimulation. These results suggest that TNF-alpha introduces a higher degree of organized cell collective migration.

  7. Multiscale mechanisms of cell migration during development: theory and experiment.

    Science.gov (United States)

    McLennan, Rebecca; Dyson, Louise; Prather, Katherine W; Morrison, Jason A; Baker, Ruth E; Maini, Philip K; Kulesa, Paul M

    2012-08-01

    Long-distance cell migration is an important feature of embryonic development, adult morphogenesis and cancer, yet the mechanisms that drive subpopulations of cells to distinct targets are poorly understood. Here, we use the embryonic neural crest (NC) in tandem with theoretical studies to evaluate model mechanisms of long-distance cell migration. We find that a simple chemotaxis model is insufficient to explain our experimental data. Instead, model simulations predict that NC cell migration requires leading cells to respond to long-range guidance signals and trailing cells to short-range cues in order to maintain a directed, multicellular stream. Experiments confirm differences in leading versus trailing NC cell subpopulations, manifested in unique cell orientation and gene expression patterns that respond to non-linear tissue growth of the migratory domain. Ablation experiments that delete the trailing NC cell subpopulation reveal that leading NC cells distribute all along the migratory pathway and develop a leading/trailing cellular orientation and gene expression profile that is predicted by model simulations. Transplantation experiments and model predictions that move trailing NC cells to the migratory front, or vice versa, reveal that cells adopt a gene expression profile and cell behaviors corresponding to the new position within the migratory stream. These results offer a mechanistic model in which leading cells create and respond to a cell-induced chemotactic gradient and transmit guidance information to trailing cells that use short-range signals to move in a directional manner.

  8. Uronyl 2-O sulfotransferase potentiates Fgf2-induced cell migration.

    Science.gov (United States)

    Nikolovska, Katerina; Spillmann, Dorothe; Seidler, Daniela G

    2015-02-01

    Fibroblast growth factor 2 (Fgf2) is involved in several biological functions. Fgf2 requires glycosaminoglycans, like chondroitin and dermatan sulfates (hereafter denoted CS/DS) as co-receptors. CS/DS are linear polysaccharides composed of repeating disaccharide units [-4GlcUAb1-3-GalNAc-b1-] and [-4IdoUAa1-3-GalNAc-b1-],which can be sulfated. Uronyl 2-O-sulfotransferase (Ust)introduces sulfation at the C2 of IdoUA and GlcUA resulting inover-sulfated units. Here, we investigated the role of Ust-mediated CS/DS 2-O sulfation in Fgf2-induced cell migration. We found that CHO-K1 cells overexpressing Ust contain significantly more CS/DS2-O sulfated units, whereas Ust knockdown abolished CS/DS 2-O sulfation. These structural differences in CS/DS resulted in altered Fgf2 binding and increased phosphorylation of ERK1/2 (also known as MAPK3 and MAPK1, respectively). As a functional consequence of CS/DS 2-O sulfation and altered Fgf2 binding, cell migration and paxillin activation were increased. Inhibition of sulfation, knockdown of Ust and inhibition of FgfR resulted in reduced migration. Similarly, in 3T3 cells Fgf2 treatment increased migration, which was abolished by Ust knockdown. The proteoglycan controlling the CHO migration was syndecan 1. Knockdown of Sdc1 in CHO-K1 cells overexpressing Ust abolished cell migration.We conclude that the presence of distinctly sulfated CS/DS can tune the Fgf2 effect on cell migration.

  9. Commitment of Satellite Cells Expressing the Calcium Channel α2δ1 Subunit to the Muscle Lineage

    Directory of Open Access Journals (Sweden)

    Tammy Tamayo

    2012-01-01

    Full Text Available Satellite cells can maintain or repair muscle because they possess stem cell properties, making them a valuable option for cell therapy. However, cell transplants into skeletal muscle of patients with muscular dystrophy are limited by donor cell attachment, migration, and survival in the host tissue. Cells used for therapy are selected based on specific markers present in the plasma membrane. Although many markers have been identified, there is a need to find a marker that is expressed at different states in satellite cells, activated, quiescent, or differentiated cell. Furthermore, the marker has to be present in human tissue. Recently we reported that the plasma membrane α2δ1 protein is involved in cell attachment and migration in myoblasts. The α2δ1 subunit forms a part of the L-type voltage-dependent calcium channel in adult skeletal muscle. We found that the α2δ1 subunit is expressed in the majority of newly isolated satellite cells and that it appears earlier than the α1 subunits and at higher levels than the β or γ subunits. We also found that those cells that expressed α2δ1 would differentiate into muscle cells. This evidence indicates that the α2δ1 may be used as a marker of satellite cells that will differentiate into muscle.

  10. Insulin promotes cell migration by regulating PSA-NCAM.

    Science.gov (United States)

    Monzo, Hector J; Coppieters, Natacha; Park, Thomas I H; Dieriks, Birger V; Faull, Richard L M; Dragunow, Mike; Curtis, Maurice A

    2017-06-01

    Cellular interactions with the extracellular environment are modulated by cell surface polysialic acid (PSA) carried by the neural cell adhesion molecule (NCAM). PSA-NCAM is involved in cellular processes such as differentiation, plasticity, and migration, and is elevated in Alzheimer's disease as well as in metastatic tumour cells. Our previous work demonstrated that insulin enhances the abundance of cell surface PSA by inhibiting PSA-NCAM endocytosis. In the present study we have identified a mechanism for insulin-dependent inhibition of PSA-NCAM turnover affecting cell migration. Insulin enhanced the phosphorylation of the focal adhesion kinase leading to dissociation of αv-integrin/PSA-NCAM clusters, and promoted cell migration. Our results show that αv-integrin plays a key role in the PSA-NCAM turnover process. αv-integrin knockdown stopped PSA-NCAM from being endocytosed, and αv-integrin/PSA-NCAM clusters co-labelled intracellularly with Rab5, altogether indicating a role for αv-integrin as a carrier for PSA-NCAM during internalisation. Furthermore, inhibition of p-FAK caused dissociation of αv-integrin/PSA-NCAM clusters and counteracted the insulin-induced accumulation of PSA at the cell surface and cell migration was impaired. Our data reveal a functional association between the insulin/p-FAK-dependent regulation of PSA-NCAM turnover and cell migration through the extracellular matrix. Most importantly, they identify a novel mechanism for insulin-stimulated cell migration. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Cell collectivity regulation within migrating cell cluster during Kupffer’s vesicle formation in zebrafish

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    Takaaki eMatsui

    2015-05-01

    Full Text Available Although cell adhesion is thought to fasten cells tightly, cells that adhere to each other can migrate directionally. This group behavior, called collective cell migration, is observed during normal development, wound healing, and cancer invasion. Loss-of-function of cell adhesion molecules in several model systems of collective cell migration results in delay or inhibition of migration of cell groups but does not lead to dissociation of the cell groups, suggesting that mechanisms of cells staying assembled as a single cell cluster, termed as cell collectivity, remain largely unknown. During the formation of Kupffer’s vesicle (KV, an organ of laterality in zebrafish, KV progenitors form a cluster and migrate together toward the vegetal pole. Importantly, in this model system of collective cell migration, knockdown of cell adhesion molecules or signal components leads to failure of cell collectivity. In this review, we summarize recent findings in cell collectivity regulation during collective migration of KV progenitor cells and describe our current understanding of how cell collectivity is regulated during collective cell migration.

  12. Migration and keratinization of cells in wool follicles.

    Science.gov (United States)

    Chapman, R E; Downes, A M; Wilson, P A

    1980-10-01

    Migration of cells in wool follicles of an adult Merino sheep was studied autoradiographically in skin samples taken at intervals after an intravenous injection of [3H]thymidine. Fibre and inner root sheath cells incorporated [3H]thymidine in a cone-shape region of the follicle bulb. Labelled inner sheath cells migrated out of the bulb ahead of contemporaneous cells in the fibre and remained in advance, although to a progressively lesser extent, until the inner sheath cells sloughed into the follicle lumen. Outer root sheath cells incorporated [3H]thymidine along the length of the follicle. Cells in the proximal half of the outer sheath migrated inwards and distally and sloughed into the follicle lumen before contemporaneous inner sheath cells. Other cells in the distal half of the outer sheath migrated past the level where cells from the proximal population were shed and also sloughed into the lumen. In the most distal part of the outer sheath, which formed the epidermis-like lining of the follicle canal, little migration of cells was observed during 8 days of observation. The specific activity of tritium in fibres plucked from the same sheep at intervals after the intravenous injection of [3H]thymidine was determined by scintillation counting and assessed in terms of cell migration and hardening of the fibres. The time which the specific activity of solvent-degreased fibres reached a maximum was found to give an estimate of the time for cells in the fibre to migrate to the upper limit of the keratogenous zone. When the plucked fibres were extracted with 8 M urea the times of the maximum specific activities of the urea-dispersible and urea-insoluble material provided respectively estimates of the times at which hardening of the fibres began and ended. The effects of different planes of nutrition were examined in two other Merino sheep by radioassay of fibres plucked after intravenous injections of [3H]thymidine given after equilibration period of at least 2 months

  13. How Tissue Mechanical Properties Affect Enteric Neural Crest Cell Migration.

    Science.gov (United States)

    Chevalier, N R; Gazguez, E; Bidault, L; Guilbert, T; Vias, C; Vian, E; Watanabe, Y; Muller, L; Germain, S; Bondurand, N; Dufour, S; Fleury, V

    2016-02-18

    Neural crest cells (NCCs) are a population of multipotent cells that migrate extensively during vertebrate development. Alterations to neural crest ontogenesis cause several diseases, including cancers and congenital defects, such as Hirschprung disease, which results from incomplete colonization of the colon by enteric NCCs (ENCCs). We investigated the influence of the stiffness and structure of the environment on ENCC migration in vitro and during colonization of the gastrointestinal tract in chicken and mouse embryos. We showed using tensile stretching and atomic force microscopy (AFM) that the mesenchyme of the gut was initially soft but gradually stiffened during the period of ENCC colonization. Second-harmonic generation (SHG) microscopy revealed that this stiffening was associated with a gradual organization and enrichment of collagen fibers in the developing gut. Ex-vivo 2D cell migration assays showed that ENCCs migrated on substrates with very low levels of stiffness. In 3D collagen gels, the speed of the ENCC migratory front decreased with increasing gel stiffness, whereas no correlation was found between porosity and ENCC migration behavior. Metalloprotease inhibition experiments showed that ENCCs actively degraded collagen in order to progress. These results shed light on the role of the mechanical properties of tissues in ENCC migration during development.

  14. Loss of Gadkin Affects Dendritic Cell Migration In Vitro.

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    Hannah Schachtner

    Full Text Available Migration is crucial for the function of dendritic cells (DCs, which act as outposts of the immune system. Upon detection of pathogens, skin- and mucosa-resident DCs migrate to secondary lymphoid organs where they activate T cells. DC motility relies critically on the actin cytoskeleton, which is regulated by the actin-related protein 2/3 (ARP2/3 complex, a nucleator of branched actin networks. Consequently, loss of ARP2/3 stimulators and upstream Rho family GTPases dramatically impairs DC migration. However, nothing is known yet about the relevance of ARP2/3 inhibitors for DC migration. We previously demonstrated that the AP-1-associated adaptor protein Gadkin inhibits ARP2/3 by sequestering it on intracellular vesicles. Consistent with a role of Gadkin in DC physiology, we here report Gadkin expression in bone marrow-derived DCs and show that its protein level and posttranslational modification are regulated upon LPS-induced DC maturation. DCs derived from Gadkin-deficient mice were normal with regards to differentiation and maturation, but displayed increased actin polymerization. While the actin-dependent processes of macropinocytosis and cell spreading were not affected, loss of Gadkin significantly impaired DC migration in vitro, however, in vivo DC migration was unperturbed suggesting the presence of compensatory mechanisms.

  15. Heparin inhibits human coronary artery smooth muscle cell migration.

    Science.gov (United States)

    Kohno, M; Yokokawa, K; Yasunari, K; Minami, M; Kano, H; Mandal, A K; Yoshikawa, J

    1998-09-01

    Heparin, an anticoagulant, has been shown to reduce neointimal proliferation and restenosis following vascular injury in experimental studies, but the clinical trials of heparin in coronary balloon angioplasty have been negative. The current study, therefore, examined the effect of heparin on basal or stimulated migration by serum and platelet-derived growth factor (PDGF)-BB in cultured human coronary artery smooth muscle cells (SMCs) by Boyden's chamber method. In addition, the reversibility of the heparin effect on human coronary artery SMC migration was examined. Fetal calf serum (FCS) and PDGF-BB stimulated SMC migration in a concentration-dependent manner. Heparin in moderate to high concentration (10 to 100 U/mL) exhibited concentration-related inhibition of FCS- and PDGF-BB-stimulated SMC migration; however, a low concentration (1 U/mL) of heparin had no inhibitory effects. Heparin also had weak inhibitory effects on nonstimulated SMC migration. The SMCs that were exposed to a high concentration (100 U/mL) of heparin for 6 hours were capable of migrating after a short lag period of removal of heparin from the culture medium. These SMCs also showed recovery of responses to FCS and PDGF-BB by migrating significantly greater than the nonstimulated level. Furthermore, heparin-containing medium did not contain detached cells. These results indicate that heparin inhibits human coronary artery SMC migration, especially when stimulated by FCS or PDGF-BB, and that this inhibitory effect of heparin is reversible and not simply a function of killing cells.

  16. A global downregulation of microRNAs occurs in human quiescent satellite cells during myogenesis

    NARCIS (Netherlands)

    Koning, Merel; Werker, Paul M N; van Luyn, Marja J A; Krenning, Guido; Harmsen, Martin C

    2012-01-01

    During myogenesis, human satellite cells differentiate and form multinucleated myotubes, while a fraction of the human satellite cells enter quiescence. These quiescent satellite cells are able to activate, proliferate and contribute to muscle regeneration. Post-transcriptional regulation of

  17. Expression of aquaporin-1 in SMMC-7221 liver carcinoma cells promotes cell migration

    Institute of Scientific and Technical Information of China (English)

    LI Yongming; FENG Xuechao; YANG Hong; MA Tonghui

    2006-01-01

    Migration of tumor cells is a crucial step in tumor invasion and metastasis. Here we provide evidence that aquaporin expression is involved in tumor cell migration. RT-PCR, immunofluorescence and Western blot analysis demonstrated the AQP1 protein expression on the plasma membrane of SMMC-7221 human hepatoma cells. SMMC-7221 cell clones with high (SMMC-7221hPf) and low (SMMC-7221/Pf) water permeability were identified by functional assays with corresponding high and low AQP1 expression. Cell migration rate was remarkably higher in SMMC-7221hPf cells than SMMC-7221/Pf cells, assessed by Boyden chamber and wound healing assays, whereas cell growth and adhesion were not different. Adenovirus-mediated AQP1 expression in SMMC-7221/Pf cells increased their water permeability and migration rate. These results provide the first evidence that aquaporin-mediated membrane water permeability enhances tumor cell migration and may be associated with tumor invasion and metastasis.

  18. Stem cells migration during skeletal muscle regeneration - the role of Sdf-1/Cxcr4 and Sdf-1/Cxcr7 axis.

    Science.gov (United States)

    Kowalski, Kamil; Kołodziejczyk, Aleksandra; Sikorska, Maria; Płaczkiewicz, Jagoda; Cichosz, Paulina; Kowalewska, Magdalena; Stremińska, Władysława; Jańczyk-Ilach, Katarzyna; Koblowska, Marta; Fogtman, Anna; Iwanicka-Nowicka, Roksana; Ciemerych, Maria A; Brzoska, Edyta

    2016-10-13

    The skeletal muscle regeneration occurs due to the presence of tissue specific stem cells - satellite cells. These cells, localized between sarcolemma and basal lamina, are bound to muscle fibers and remain quiescent until their activation upon muscle injury. Due to pathological conditions, such as extensive injury or dystrophy, skeletal muscle regeneration is diminished. Among the therapies aiming to ameliorate skeletal muscle diseases are transplantations of the stem cells. In our previous studies we showed that Sdf-1 (stromal derived factor -1) increased migration of stem cells and their fusion with myoblasts in vitro. Importantly, we identified that Sdf-1 caused an increase in the expression of tetraspanin CD9 - adhesion protein involved in myoblasts fusion. In the current study we aimed to uncover the details of molecular mechanism of Sdf-1 action. We focused at the Sdf-1 receptors - Cxcr4 and Cxcr7, as well as signaling pathways induced by these molecules in primary myoblasts, as well as various stem cells - mesenchymal stem cells and embryonic stem cells, i.e. the cells of different migration and myogenic potential. We showed that Sdf-1 altered actin organization via FAK (focal adhesion kinase), Cdc42 (cell division control protein 42), and Rac-1 (Ras-Related C3 Botulinum Toxin Substrate 1). Moreover, we showed that Sdf-1 modified the transcription profile of genes encoding factors engaged in cells adhesion and migration. As the result, cells such as primary myoblasts or embryonic stem cells, became characterized by more effective migration when transplanted into regenerating muscle.

  19. Leukotrienes induce the migration of Th17 cells.

    Science.gov (United States)

    Lee, Wonyong; Su Kim, Hyeong; Lee, Gap Ryol

    2015-01-01

    Th17 cell trafficking in response to leukotriene signaling is poorly understood. Here we showed that Th17 cells express high levels of leukotriene B4 receptor 1 (LTB4R1) and cysteinyl leukotriene receptor 1 (CysLTR1). Th17 cells migrated under the guidance of leukotriene B4 and D4. The migration of Th17 cells was more efficient than that of Th1 and Th2 cells, and it was blocked by specific inhibitors of LTB4R1 or CysLTR1. Studies in an animal model of experimental autoimmune encephalomyelitis revealed that treatment with montelukast alleviated disease symptoms and inhibited the recruitment of Th17 cells to the central nervous system. Thus, leukotrienes may act as chemoattractants for Th17 cells.

  20. Subventricular zone cell migration: lessons from quantitative 2-photon microscopy

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    Rachel eJames

    2011-03-01

    Full Text Available Neuroblasts born in the adult subventricular zone (SVZ migrate long distances in the rostral migratory stream (RMS to the olfactory bulbs where they integrate into circuitry as functional interneurons. As very little was known about the dynamic parameters of SVZ neuroblast migration, we used two-photon time-lapse microscopy to analyze migration in acute slices. This involved analyzing 3-dimensional stacks of images over time and uncovered several novel aspects of SVZ migration: chains remain stable, cells can be immotile for extensive periods, morphology does not necessarily correlate with motility, neuroblasts exhibit local exploratory motility, dorsoventral migration occurs throughout the striatal SVZ and neuroblasts turn at distinctive angles. We investigated these novel findings in the SVZ and RMS from the population to the single cell level. In this review we also discuss some technical considerations when setting up a two-photon microscopic imaging system. Throughout the review we identify several unsolved questions about SVZ neuroblast migration that might be addressed with current or emerging techniques.

  1. Epac Activation Regulates Human Mesenchymal Stem Cells Migration and Adhesion.

    Science.gov (United States)

    Yu, Jiao-Le; Deng, Ruixia; Chung, Sookja K; Chan, Godfrey Chi-Fung

    2016-04-01

    How to enhance the homing of human mesenchymal stem cells (hMSCs) to the target tissues remains a clinical challenge nowadays. To overcome this barrier, the mechanism responsible for the hMSCs migration and engraftment has to be defined. Currently, the exact mechanism involved in migration and adhesion of hMSCs remains unknown. Exchange protein directly activated by cAMP (Epac), a novel protein discovered in cAMP signaling pathway, may have a potential role in regulating cells adhesion and migration by triggering the downstream Rap family signaling cascades. However, the exact role of Epac in cells homing is elusive. Our study evaluated the role of Epac in the homing of hMSCs. We confirmed that hMSCs expressed functional Epac and its activation enhanced the migration and adhesion of hMSCs significantly. The Epac activation was further found to be contributed directly to the chemotactic responses induced by stromal cell derived factor-1 (SDF-1) which is a known chemokine in regulating hMSCs homing. These findings suggested Epac is connected to the SDF-1 signaling cascades. In conclusion, our study revealed that Epac plays a role in hMSCs homing by promoting adhesion and migration. Appropriate manipulation of Epac may enhance the homing of hMSCs and facilitate their future clinical applications.

  2. High glucose-mediated oxidative stress impairs cell migration.

    Directory of Open Access Journals (Sweden)

    Marcelo L Lamers

    Full Text Available Deficient wound healing in diabetic patients is very frequent, but the cellular and molecular causes are poorly defined. In this study, we evaluate the hypothesis that high glucose concentrations inhibit cell migration. Using CHO.K1 cells, NIH-3T3 fibroblasts, mouse embryonic fibroblasts and primary skin fibroblasts from control and diabetic rats cultured in 5 mM D-glucose (low glucose, LG, 25 mM D-glucose (high glucose, HG or 25 mM L-glucose medium (osmotic control--OC, we analyzed the migration speed, protrusion stability, cell polarity, adhesion maturation and the activity of the small Rho GTPase Rac1. We also analyzed the effects of reactive oxygen species by incubating cells with the antioxidant N-Acetyl-Cysteine (NAC. We observed that HG conditions inhibited cell migration when compared to LG or OC. This inhibition resulted from impaired cell polarity, protrusion destabilization and inhibition of adhesion maturation. Conversely, Rac1 activity, which promotes protrusion and blocks adhesion maturation, was increased in HG conditions, thus providing a mechanistic basis for the HG phenotype. Most of the HG effects were partially or completely rescued by treatment with NAC. These findings demonstrate that HG impairs cell migration due to an increase in oxidative stress that causes polarity loss, deficient adhesion and protrusion. These alterations arise, in large part, from increased Rac1 activity and may contribute to the poor wound healing observed in diabetic patients.

  3. Use of Advanced Solar Cells for Commercial Communication Satellites

    Science.gov (United States)

    Bailey, Sheila G.; Landis, Geoffrey A.

    1995-01-01

    The current generation of communications satellites are located primarily in geosynchronous Earth orbit (GEO). Over the next decade, however, a new generation of communications satellites will be built and launched, designed to provide a world-wide interconnection of portable telephones. For this mission, the satellites must be positioned in lower polar and near-polar orbits. To provide complete coverage, large numbers of satellites will be required. Because the required number of satellites decreases as the orbital altitude is increased, fewer satellites would be required if the orbit chosen were raised from low to intermediate orbit. However, in intermediate orbits, satellites encounter significant radiation due to trapped electrons and protons. Radiation tolerant solar cells may be necessary to make such satellites feasible. We analyze the amount of radiation encountered in low and intermediate polar orbits at altitudes of interest to next-generation communication satellites, calculate the expected degradation for silicon, GaAs, and InP solar cells, and show that the lifetimes can be significantly increased by use of advanced solar cells.

  4. In search of greener pastures: Using satellite images to predict the effects of environmental change on zebra migration

    Science.gov (United States)

    Bartlam-Brooks, Hattie L. A.; Beck, Pieter S. A.; Bohrer, Gil; Harris, Stephen

    2013-12-01

    ungulate migrations occurred in most grassland and boreal woodland ecosystems, but many have been lost due to increasing habitat loss and fragmentation. With the rate of environmental change increasing, identifying and prioritizing migration routes for conservation has taken on a new urgency. Understanding the cues that drive long-distance animal movements is critical to predicting the fate of migrations under different environmental change scenarios and how large migratory herbivores will respond to increasing resource heterogeneity and anthropogenic influences. We used an individual-based modeling approach to investigate the influence of environmental conditions, monitored using satellite data, on departure date and movement speed of migrating zebras in Botswana. Daily zebra movements between dry and rainy season ranges were annotated with coincident observations of precipitation from the Tropical Rainfall Measuring Mission data set and Moderate Resolution Imaging Spectroradiometer-derived normalized difference vegetation index (NDVI). An array of increasingly complex movement models representing alternative hypotheses regarding the environmental cues and controls for movement was parameterized and tested. The best and most justified model predicted daily zebra movement as two linear functions of precipitation rate and NDVI and included a modeled departure date as a function of cumulative precipitation. The model was highly successful at replicating both the timing and pace of seven actual migrations observed using GPS telemetry (R2 = 0.914). It shows how zebras rapidly adjust their movement to changing environmental conditions during migration and are able to reverse migration to avoid adverse conditions or exploit renewed resource availability, a nomadic behavior which should lend them a degree of resilience to climate and environmental change. Our results demonstrate how competing individual-based migration models, informed by freely available satellite data

  5. Collisions of deformable cells lead to collective migration

    Science.gov (United States)

    Löber, Jakob; Ziebert, Falko; Aranson, Igor S.

    2015-03-01

    Collective migration of eukaryotic cells plays a fundamental role in tissue growth, wound healing and immune response. The motion, arising spontaneously or in response to chemical and mechanical stimuli, is also important for understanding life-threatening pathologies, such as cancer and metastasis formation. We present a phase-field model to describe the movement of many self-organized, interacting cells. The model takes into account the main mechanisms of cell motility - acto-myosin dynamics, as well as substrate-mediated and cell-cell adhesion. It predicts that collective cell migration emerges spontaneously as a result of inelastic collisions between neighboring cells: collisions lead to a mutual alignment of the cell velocities and to the formation of coherently-moving multi-cellular clusters. Small cell-to-cell adhesion, in turn, reduces the propensity for large-scale collective migration, while higher adhesion leads to the formation of moving bands. Our study provides valuable insight into biological processes associated with collective cell motility.

  6. Modeling keratinocyte wound healing dynamics: Cell-cell adhesion promotes sustained collective migration.

    Science.gov (United States)

    Nardini, John T; Chapnick, Douglas A; Liu, Xuedong; Bortz, David M

    2016-07-07

    The in vitro migration of keratinocyte cell sheets displays behavioral and biochemical similarities to the in vivo wound healing response of keratinocytes in animal model systems. In both cases, ligand-dependent Epidermal Growth Factor Receptor (EGFR) activation is sufficient to elicit collective cell migration into the wound. Previous mathematical modeling studies of in vitro wound healing assays assume that physical connections between cells have a hindering effect on cell migration, but biological literature suggests a more complicated story. By combining mathematical modeling and experimental observations of collectively migrating sheets of keratinocytes, we investigate the role of cell-cell adhesion during in vitro keratinocyte wound healing assays. We develop and compare two nonlinear diffusion models of the wound healing process in which cell-cell adhesion either hinders or promotes migration. Both models can accurately fit the leading edge propagation of cell sheets during wound healing when using a time-dependent rate of cell-cell adhesion strength. The model that assumes a positive role of cell-cell adhesion on migration, however, is robust to changes in the leading edge definition and yields a qualitatively accurate density profile. Using RNAi for the critical adherens junction protein, α-catenin, we demonstrate that cell sheets with wild type cell-cell adhesion expression maintain migration into the wound longer than cell sheets with decreased cell-cell adhesion expression, which fails to exhibit collective migration. Our modeling and experimental data thus suggest that cell-cell adhesion promotes sustained migration as cells pull neighboring cells into the wound during wound healing.

  7. Effective fiber hypertrophy in satellite cell-depleted skeletal muscle.

    Science.gov (United States)

    McCarthy, John J; Mula, Jyothi; Miyazaki, Mitsunori; Erfani, Rod; Garrison, Kelcye; Farooqui, Amreen B; Srikuea, Ratchakrit; Lawson, Benjamin A; Grimes, Barry; Keller, Charles; Van Zant, Gary; Campbell, Kenneth S; Esser, Karyn A; Dupont-Versteegden, Esther E; Peterson, Charlotte A

    2011-09-01

    An important unresolved question in skeletal muscle plasticity is whether satellite cells are necessary for muscle fiber hypertrophy. To address this issue, a novel mouse strain (Pax7-DTA) was created which enabled the conditional ablation of >90% of satellite cells in mature skeletal muscle following tamoxifen administration. To test the hypothesis that satellite cells are necessary for skeletal muscle hypertrophy, the plantaris muscle of adult Pax7-DTA mice was subjected to mechanical overload by surgical removal of the synergist muscle. Following two weeks of overload, satellite cell-depleted muscle showed the same increases in muscle mass (approximately twofold) and fiber cross-sectional area with hypertrophy as observed in the vehicle-treated group. The typical increase in myonuclei with hypertrophy was absent in satellite cell-depleted fibers, resulting in expansion of the myonuclear domain. Consistent with lack of nuclear addition to enlarged fibers, long-term BrdU labeling showed a significant reduction in the number of BrdU-positive myonuclei in satellite cell-depleted muscle compared with vehicle-treated muscle. Single fiber functional analyses showed no difference in specific force, Ca(2+) sensitivity, rate of cross-bridge cycling and cooperativity between hypertrophied fibers from vehicle and tamoxifen-treated groups. Although a small component of the hypertrophic response, both fiber hyperplasia and regeneration were significantly blunted following satellite cell depletion, indicating a distinct requirement for satellite cells during these processes. These results provide convincing evidence that skeletal muscle fibers are capable of mounting a robust hypertrophic response to mechanical overload that is not dependent on satellite cells.

  8. Effective fiber hypertrophy in satellite cell-depleted skeletal muscle

    Science.gov (United States)

    McCarthy, John J.; Mula, Jyothi; Miyazaki, Mitsunori; Erfani, Rod; Garrison, Kelcye; Farooqui, Amreen B.; Srikuea, Ratchakrit; Lawson, Benjamin A.; Grimes, Barry; Keller, Charles; Van Zant, Gary; Campbell, Kenneth S.; Esser, Karyn A.; Dupont-Versteegden, Esther E.; Peterson, Charlotte A.

    2011-01-01

    An important unresolved question in skeletal muscle plasticity is whether satellite cells are necessary for muscle fiber hypertrophy. To address this issue, a novel mouse strain (Pax7-DTA) was created which enabled the conditional ablation of >90% of satellite cells in mature skeletal muscle following tamoxifen administration. To test the hypothesis that satellite cells are necessary for skeletal muscle hypertrophy, the plantaris muscle of adult Pax7-DTA mice was subjected to mechanical overload by surgical removal of the synergist muscle. Following two weeks of overload, satellite cell-depleted muscle showed the same increases in muscle mass (approximately twofold) and fiber cross-sectional area with hypertrophy as observed in the vehicle-treated group. The typical increase in myonuclei with hypertrophy was absent in satellite cell-depleted fibers, resulting in expansion of the myonuclear domain. Consistent with lack of nuclear addition to enlarged fibers, long-term BrdU labeling showed a significant reduction in the number of BrdU-positive myonuclei in satellite cell-depleted muscle compared with vehicle-treated muscle. Single fiber functional analyses showed no difference in specific force, Ca2+ sensitivity, rate of cross-bridge cycling and cooperativity between hypertrophied fibers from vehicle and tamoxifen-treated groups. Although a small component of the hypertrophic response, both fiber hyperplasia and regeneration were significantly blunted following satellite cell depletion, indicating a distinct requirement for satellite cells during these processes. These results provide convincing evidence that skeletal muscle fibers are capable of mounting a robust hypertrophic response to mechanical overload that is not dependent on satellite cells. PMID:21828094

  9. Capturing Trojans and Irregular Satellites - the key required to unlock planetary migration

    CERN Document Server

    Horner, Jonathan; Lykawka, Patryk Sofia

    2013-01-01

    It is now accepted that the Solar system's youth was a dynamic and chaotic time. The giant planets migrated significant distances to reach their current locations, and evidence of that migration's influence on the Solar system abounds. That migration's pace, and the distance over which it occurred, is still heavily debated. Some models feature systems in which the giant planets were initially in an extremely compact configuration, in which Uranus and Neptune are chaotically scattered into the outer Solar system. Others feature architectures that were initially more relaxed, and smoother, more sedate migration. To determine which of these scenarios best represents the formation of our Solar system, we must turn to the structure of the system's small body populations, in which the scars of that migration are still clearly visible. We present the first results of a program investigating the effect of giant planet migration on the reservoirs of small bodies that existed at that time. As the planets migrate, they ...

  10. Effect of 7-hydroxystaurosporine on glioblastoma cell invasion and migration

    Institute of Scientific and Technical Information of China (English)

    Qing-hui MENG; Li-xin ZHOU; Jia-lin LUO; Jian-ping CAO; Jian TONG; Sai-jun FAN

    2005-01-01

    Aim: To investigate the effect of 7-hydroxystaurosporine (UCN-01), a selective protein kinase C (PKC) inhibitor, on cell growth, migration, and invasion in inva sive human glioblastoma U-87MG cells. Methods: PKC activity was determined based on the PKC-catalyzed transfer of the 32p-phosphate group from [g-32p]ATP into a PKC-specific peptide substrate. Cell viability was measured by MTT assay.Cell invasion and migration were evaluated by a Boyden chamber assay and scratch wound assay, respectively. Protein expression was analyzed using Western blot assay. The formation of 3-dimensional cellular aggregates was examined by a cell-cell aggregation assay. Results: UCN-01 treatment resulted in concentration- and time-dependent inhibition of U-87MG cell growth at higher doses (> 100 nmol/L), and reduced cell invasion and migration capability at less cytotoxic doses (<100 nmol/L). UCN-01 significantly repressed PKC activity. Consistent with this result, UCN-01 blocked cell invasion stimulated by phorbel 12-myristate13-acetate (PMA) and ethanol (EtOH), 2 PKC activators. Enforced expression of the tumor suppressor genes BRCA1 and PTEN increased the anti-invasion potential of UCN-01. Exposure to UCN-01 caused a dose-dependent increase in cell adhesion molecule E-cadherin. The effect of UCN-01 on the formation of cell-cell aggregation was significantly reduced by the addition of an anti-E-cadherin antibody. Conclusion: UCN-01 inhibits the invasion and migration of human glioma cells. Accordingly, UCN-01 can have potential clinical applications for the treatment of human glioma metastasis.

  11. M-cadherin-mediated intercellular interactions activate satellite cell division.

    Science.gov (United States)

    Marti, Merce; Montserrat, Núria; Pardo, Cristina; Mulero, Lola; Miquel-Serra, Laia; Rodrigues, Alexandre Miguel Cavaco; Andrés Vaquero, José; Kuebler, Bernd; Morera, Cristina; Barrero, María José; Izpisua Belmonte, Juan Carlos

    2013-11-15

    Adult muscle stem cells and their committed myogenic precursors, commonly referred to as the satellite cell population, are involved in both muscle growth after birth and regeneration after damage. It has been previously proposed that, under these circumstances, satellite cells first become activated, divide and differentiate, and only later fuse to the existing myofiber through M-cadherin-mediated intercellular interactions. Our data show that satellite cells fuse with the myofiber concomitantly to cell division, and only when the nuclei of the daughter cells are inside the myofiber, do they complete the process of differentiation. Here we demonstrate that M-cadherin plays an important role in cell-to-cell recognition and fusion, and is crucial for cell division activation. Treatment of satellite cells with M-cadherin in vitro stimulates cell division, whereas addition of anti-M-cadherin antibodies reduces the cell division rate. Our results suggest an alternative model for the contribution of satellite cells to muscle development, which might be useful in understanding muscle regeneration, as well as muscle-related dystrophies.

  12. Cell Migration According to Shape of Graphene Oxide Micropatterns

    Directory of Open Access Journals (Sweden)

    Sung Eun Kim

    2016-10-01

    Full Text Available Photolithography is a unique process that can effectively manufacture micro/nano-sized patterns on various substrates. On the other hand, the meniscus-dragging deposition (MDD process can produce a uniform surface of the substrate. Graphene oxide (GO is the oxidized form of graphene that has high hydrophilicity and protein absorption. It is widely used in biomedical fields such as drug delivery, regenerative medicine, and tissue engineering. Herein, we fabricated uniform GO micropatterns via MDD and photolithography. The physicochemical properties of the GO micropatterns were characterized by atomic force microscopy (AFM, scanning electron microscopy (SEM, and Raman spectroscopy. Furthermore, cell migration on the GO micropatterns was investigated, and the difference in cell migration on triangle and square GO micropatterns was examined for their effects on cell migration. Our results demonstrated that the GO micropatterns with a desired shape can be finely fabricated via MDD and photolithography. Moreover, it was revealed that the shape of GO micropatterns plays a crucial role in cell migration distance, speed, and directionality. Therefore, our findings suggest that the GO micropatterns can serve as a promising biofunctional platform and cell-guiding substrate for applications to bioelectric devices, cell-on-a-chip, and tissue engineering scaffolds.

  13. First description of autumn migration of Sooty Falcon Falco concolor from the United Arab Emirates to Madagascar using satellite telemetry

    Science.gov (United States)

    Javed, Salim; Douglas, David C.; Khan, Shahid Noor; Nazeer Shah, Junid; Ali Al Hammadi, Abdullah

    2012-01-01

    The movement and migration pattern of the 'Near Threatened' Sooty Falcon Falco concolor is poorly known. Sooty Falcons breed on the islands of the Arabian Gulf after arriving from their non-breeding areas that are mainly in Madagascar. In the first satellite tracking of the species we fitted a 9.5 g Argos solar powered transmitter on an adult breeding Sooty Falcon off the western coast of Abu Dhabi in the United Arab Emirates. The bird successfully undertook autumn migration to Madagascar, a known wintering area for the species. We document the Sooty Falcon's autumn migration route and stop-over sites. The adult Sooty Falcon initiated its migration at night and with tailwinds, and travelled mainly during daytime hours for 13 days over an inland route of more than 5,656 km. The three stop-over sites in East Africa were characterised by moderate to sparse shrub cover associated with potential sources of water. We discuss the migration pattern of the tracked bird in relation to importance of non-breeding areas for Sooty Falcons and recent declines in numbers in their breeding range.

  14. Nuclear envelope rupture and repair during cancer cell migration

    Science.gov (United States)

    Denais, Celine M.; Gilbert, Rachel M.; Isermann, Philipp; McGregor, Alexandra L.; te Lindert, Mariska; Weigelin, Bettina; Davidson, Patricia M.; Friedl, Peter; Wolf, Katarina; Lammerding, Jan

    2016-01-01

    During cancer metastasis, tumor cells penetrate tissues through tight interstitial spaces, requiring extensive deformation of the cell and its nucleus. Here, we investigated tumor cell migration in confining microenvironments in vitro and in vivo. Nuclear deformation caused localized loss of nuclear envelope (NE) integrity, which led to the uncontrolled exchange of nucleo-cytoplasmic content, herniation of chromatin across the NE, and DNA damage. The incidence of NE rupture increased with cell confinement and with depletion of nuclear lamins, NE proteins that structurally support the nucleus. Cells restored NE integrity using components of the endosomal sorting complexes required for transport-III (ESCRT-III) machinery. Our findings indicate that cell migration incurs substantial physical stress on the NE and its content, requiring efficient NE and DNA damage repair for survival. PMID:27013428

  15. Leader Cells Define Directionality of Trunk, but Not Cranial, Neural Crest Cell Migration.

    Science.gov (United States)

    Richardson, Jo; Gauert, Anton; Briones Montecinos, Luis; Fanlo, Lucía; Alhashem, Zainalabdeen Mohmammed; Assar, Rodrigo; Marti, Elisa; Kabla, Alexandre; Härtel, Steffen; Linker, Claudia

    2016-05-31

    Collective cell migration is fundamental for life and a hallmark of cancer. Neural crest (NC) cells migrate collectively, but the mechanisms governing this process remain controversial. Previous analyses in Xenopus indicate that cranial NC (CNC) cells are a homogeneous population relying on cell-cell interactions for directional migration, while chick embryo analyses suggest a heterogeneous population with leader cells instructing directionality. Our data in chick and zebrafish embryos show that CNC cells do not require leader cells for migration and all cells present similar migratory capacities. In contrast, laser ablation of trunk NC (TNC) cells shows that leader cells direct movement and cell-cell contacts are required for migration. Moreover, leader and follower identities are acquired before the initiation of migration and remain fixed thereafter. Thus, two distinct mechanisms establish the directionality of CNC cells and TNC cells. This implies the existence of multiple molecular mechanisms for collective cell migration. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  16. Surface topography during neural stem cell differentiation regulates cell migration and cell morphology.

    Science.gov (United States)

    Czeisler, Catherine; Short, Aaron; Nelson, Tyler; Gygli, Patrick; Ortiz, Cristina; Catacutan, Fay Patsy; Stocker, Ben; Cronin, James; Lannutti, John; Winter, Jessica; Otero, José Javier

    2016-12-01

    We sought to determine the contribution of scaffold topography to the migration and morphology of neural stem cells by mimicking anatomical features of scaffolds found in vivo. We mimicked two types of central nervous system scaffolds encountered by neural stem cells during development in vitro by constructing different diameter electrospun polycaprolactone (PCL) fiber mats, a substrate that we have shown to be topographically similar to brain scaffolds. We compared the effects of large fibers (made to mimic blood vessel topography) with those of small-diameter fibers (made to mimic radial glial process topography) on the migration and differentiation of neural stem cells. Neural stem cells showed differential migratory and morphological reactions with laminin in different topographical contexts. We demonstrate, for the first time, that neural stem cell biological responses to laminin are dependent on topographical context. Large-fiber topography without laminin prevented cell migration, which was partially reversed by treatment with rock inhibitor. Cell morphology complexity assayed by fractal dimension was inhibited in nocodazole- and cytochalasin-D-treated neural precursor cells in large-fiber topography, but was not changed in small-fiber topography with these inhibitors. These data indicate that cell morphology has different requirements on cytoskeletal proteins dependent on the topographical environment encountered by the cell. We propose that the physical structure of distinct scaffolds induces unique signaling cascades that regulate migration and morphology in embryonic neural precursor cells. J. Comp. Neurol. 524:3485-3502, 2016. © 2016 Wiley Periodicals, Inc.

  17. The MRL proteins: adapting cell adhesion, migration and growth.

    Science.gov (United States)

    Coló, Georgina P; Lafuente, Esther M; Teixidó, Joaquin

    2012-01-01

    MIG-10, RIAM and Lamellipodin (Lpd) are the founding members of the MRL family of multi-adaptor molecules. These proteins have common domain structures but display distinct functions in cell migration and adhesion, signaling, and in cell growth. The binding of RIAM with active Rap1 and with talin provides these MRL molecules with important regulatory roles on integrin-mediated cell adhesion and migration. Furthermore, RIAM and Lpd can regulate actin dynamics through their binding to actin regulatory Ena/VASP proteins. Recent data generated with the Drosophila MRL ortholog called Pico and with RIAM in melanoma cells indicate that these proteins can also regulate cell growth. As MRL proteins represent a relatively new family, many questions on their structure-function relationships remain unanswered, including regulation of their expression, post-translational modifications, new interactions, involvement in signaling and their knockout mice phenotype.

  18. Role of laminin receptor in tumor cell migration

    DEFF Research Database (Denmark)

    Wewer, U M; Taraboletti, G; Sobel, M E;

    1987-01-01

    Polyclonal antisera were made against biochemically purified laminin receptor protein as well as against synthetic peptides deduced from a complementary DNA clone corresponding to the COOH-terminal end of the laminin receptor (U.M. Wewer et al., Proc. Natl. Acad. Sci. USA, 83: 7137-7141, 1986......). These antisera were used to study the potential role of laminin receptor in laminin-mediated attachment and haptotactic migration of human A2058 melanoma cells. The anti-laminin receptor antisera reacted with the surface of suspended, nonpermeabilized melanoma and carcinoma cells. The anti-laminin receptor...... antisera blocked the surface interaction of A2058 cells with endogenous laminin, resulting in the inhibition of laminin-mediated cell attachment. The A2058 melanoma cells migrated toward a gradient of solid phase laminin or fibronectin (haptotaxis). Anti-laminin antiserum abolished haptotaxis on laminin...

  19. Long-term satellite tracking reveals variable seasonal migration strategies of basking sharks in the north-east Atlantic

    Science.gov (United States)

    Doherty, P. D.; Baxter, J. M.; Gell, F. R.; Godley, B. J.; Graham, R. T.; Hall, G.; Hall, J.; Hawkes, L. A.; Henderson, S. M.; Johnson, L.; Speedie, C.; Witt, M. J.

    2017-01-01

    Animal migration is ubiquitous in nature with individuals within a population often exhibiting varying movement strategies. The basking shark (Cetorhinus maximus) is the world’s second largest fish species, however, a comprehensive understanding of their long-term wider-ranging movements in the north-east Atlantic is currently lacking. Seventy satellite tags were deployed on basking sharks over four years (2012–2015) off the west coast of Scotland and the Isle of Man. Data from 28 satellite tags with attachment durations of over 165 days reveal post-summer ranging behaviours. Tagged sharks moved a median minimum straight-line distance of 3,633 km; achieving median displacement of 1,057 km from tagging locations. Tagged individuals exhibited one of three migration behaviours: remaining in waters of UK, Ireland and the Faroe Islands; migrating south to the Bay of Biscay or moving further south to waters off the Iberian Peninsula, and North Africa. Sharks used both continental shelf areas and oceanic habitats, primarily in the upper 50–200 m of the water column, spanning nine geo-political zones and the High Seas, demonstrating the need for multi-national cooperation in the management of this species across its range. PMID:28216646

  20. Reciprocal control of cell proliferation and migration

    Directory of Open Access Journals (Sweden)

    De Donatis Alina

    2010-09-01

    Full Text Available Abstract In adult tissue the quiescent state of a single cell is maintained by the steady state conditions of its own microenvironment for what concern both cell-cell as well as cell-ECM interaction and soluble factors concentration. Physiological or pathological conditions can alter this quiescent state through an imbalance of both soluble and insoluble factors that can trigger a cellular phenotypic response. The kind of cellular response depends by many factors but one of the most important is the concentration of soluble cytokines sensed by the target cell. In addition, due to the intrinsic plasticity of many cellular types, every single cell is able, in response to the same stimulus, to rapidly switch phenotype supporting minimal changes of microenviromental cytokines concentration. Wound healing is a typical condition in which epithelial, endothelial as well as mesenchymal cells are firstly subjected to activation of their motility in order to repopulate the damaged region and then they show a strong proliferative response in order to successfully complete the wound repair process. This schema constitute the leitmotif of many other physiological or pathological conditions such as development vasculogenesis/angiogenesis as well as cancer outgrowth and metastasis. Our review focuses on the molecular mechanisms that control the starting and, eventually, the switching of cellular phenotypic outcome in response to changes in the symmetry of the extracellular environment.

  1. Myosin IIA deficient cells migrate efficiently despite reduced traction forces at cell periphery

    Directory of Open Access Journals (Sweden)

    Melissa H. Jorrisch

    2013-02-01

    Cell motility is a cornerstone of embryogenesis, tissue remodeling and repair, and cancer cell invasion. It is generally thought that migrating cells grab and exert traction force onto the extracellular matrix in order to pull the cell body forward. While previous studies have shown that myosin II deficient cells migrate efficiently, whether these cells exert traction forces during cell migration in the absence of the major contractile machinery is currently unknown. Using an array of micron-sized pillars as a force sensor and shRNA specific to each myosin II isoform (A and B, we analyzed how myosin IIA and IIB individually regulate cell migration and traction force generation. Myosin IIA and IIB localized preferentially to the leading edge where traction force was greatest, and the trailing edge, respectively. When individual myosin II isoforms were depleted by shRNA, myosin IIA deficient cells lost actin stress fibers and focal adhesions, whereas myosin IIB deficient cells maintained similar actin organization and focal adhesions as wild-type cells. Interestingly, myosin IIA deficient cells migrated faster than wild-type or myosin IIB deficient cells on both a rigid surface and a pillar array, yet myosin IIA deficient cells exerted significantly less traction force at the leading edge than wild-type or myosin IIB deficient cells. These results suggest that, in the absence of myosin IIA mediated force-generating machinery, cells move with minimal traction forces at the cell periphery, thus demonstrating the remarkable ability of cells to adapt and migrate.

  2. Myosin IIA deficient cells migrate efficiently despite reduced traction forces at cell periphery.

    Science.gov (United States)

    Jorrisch, Melissa H; Shih, Wenting; Yamada, Soichiro

    2013-04-15

    Cell motility is a cornerstone of embryogenesis, tissue remodeling and repair, and cancer cell invasion. It is generally thought that migrating cells grab and exert traction force onto the extracellular matrix in order to pull the cell body forward. While previous studies have shown that myosin II deficient cells migrate efficiently, whether these cells exert traction forces during cell migration in the absence of the major contractile machinery is currently unknown. Using an array of micron-sized pillars as a force sensor and shRNA specific to each myosin II isoform (A and B), we analyzed how myosin IIA and IIB individually regulate cell migration and traction force generation. Myosin IIA and IIB localized preferentially to the leading edge where traction force was greatest, and the trailing edge, respectively. When individual myosin II isoforms were depleted by shRNA, myosin IIA deficient cells lost actin stress fibers and focal adhesions, whereas myosin IIB deficient cells maintained similar actin organization and focal adhesions as wild-type cells. Interestingly, myosin IIA deficient cells migrated faster than wild-type or myosin IIB deficient cells on both a rigid surface and a pillar array, yet myosin IIA deficient cells exerted significantly less traction force at the leading edge than wild-type or myosin IIB deficient cells. These results suggest that, in the absence of myosin IIA mediated force-generating machinery, cells move with minimal traction forces at the cell periphery, thus demonstrating the remarkable ability of cells to adapt and migrate.

  3. NHERF-1: Modulator of Glioblastoma Cell Migration and Invasion

    Directory of Open Access Journals (Sweden)

    Kerri L. Kislin

    2009-04-01

    Full Text Available The invasive nature of malignant gliomas is a clinical problem rendering tumors incurable by conventional treatment modalities such as surgery, ionizing radiation, and temozolomide. Na+/H+ exchanger regulatory factor 1 (NHERF-1 is a multifunctional adaptor protein, recruiting cytoplasmic signaling proteins and membrane receptors/transporters into functional complexes. This study revealed that NHERF-1 expression is increased in highly invasive cells that reside in the rim of glioblastoma multiforme (GBM tumors and that NHERF-1 sustains glioma migration and invasion. Gene expression profiles were evaluated from laser capture-microdissected human GBM cells isolated from patient tumor cores and corresponding invaded white matter regions. The role of NHERF-1 in the migration and dispersion of GBM cell lines was examined by reducing its expression with small-interfering RNA followed by radial migration, three-dimensional collagen dispersion, immunofluorescence, and survival assays. The in situ expression of NHERF-1 protein was restricted to glioma cells and the vascular endothelium, with minimal to no detection in adjacent normal brain tissue. Depletion of NHERF-1 arrested migration and dispersion of glioma cell lines and caused an increase in cell-cell cohesiveness. Glioblastoma multiforme cells with depleted NHERF-1 evidenced a marked decrease in stress fibers, a larger cell size, and a more rounded shape with fewer cellular processes. When NHERF-1 expression was reduced, glioma cells became sensitized to temozolomide treatment resulting in increased apoptosis. Taken together, these results provide the first evidence for NHERF-1 as a participant in the highly invasive phenotype of malignant gliomas and implicate NHERF-1 as a possible therapeutic target for treatment of GBM.

  4. Guidance signalling regulates leading edge behaviour during collective cell migration of cardiac cells in Drosophila.

    Science.gov (United States)

    Raza, Qanber; Jacobs, J Roger

    2016-11-15

    Collective cell migration is the coordinated movement of cells, which organize tissues during morphogenesis, repair and some cancers. The motile cell membrane of the advancing front in collective cell migration is termed the Leading Edge. The embryonic development of the vertebrate and Drosophila hearts are both characterized by the coordinated medial migration of a bilateral cluster of mesodermal cells. In Drosophila, the cardioblasts form cohesive bilateral rows that migrate collectively as a unit towards the dorsal midline to form the dorsal vessel. We have characterized the collective cell migration of cardioblasts as an in vivo quantitative model to study the behaviour of the Leading Edge. We investigated whether guidance signalling through Slit and Netrin pathways plays a role in cell migration during heart development. Through time-lapse imaging and quantitative assessment of migratory behaviour of the cardioblasts in loss-of-function mutants, we demonstrate that both Slit and Netrin mediated signals are autonomously and concomitantly required to maximize migration velocity, filopodial and lamellipodial activities. Additionally, we show that another Slit and Netrin receptor, Dscam1, the role of which during heart development was previously unknown, is required for both normal migration of cardioblasts and luminal expansion. Leading edge behaviour analysis revealed a dosage dependent genetic interaction between Slit and Netrin receptors suggesting that downstream signalling through these receptors converge on a common output that increases leading edge activity of the cardioblasts. Finally, we found that guidance signalling maintains the balance between epithelial and mesenchymal characteristics of the migrating cardioblasts.

  5. Migrastatin analogues inhibit canine mammary cancer cell migration and invasion.

    Directory of Open Access Journals (Sweden)

    Kinga Majchrzak

    Full Text Available BACKGROUND: Cancer spread to other organs is the main cause of death of oncological patients. Migration of cancer cells from a primary tumour is the crucial step in the complex process of metastasis, therefore blocking this process is currently the main treatment strategy. Metastasis inhibitors derived from natural products, such as, migrastatin, are very promising anticancer agents. Thus, the aim of our study was to investigate the effect of six migrastatin analogues (MGSTA-1 to 6 on migration and invasion of canine mammary adenocarcinoma cell lines isolated from primary tumours and their metastases to the lungs. Canine mammary tumours constitute a valuable tool for studying multiple aspect of human cancer. RESULTS: OUR RESULTS SHOWED THAT TWO OF SIX FULLY SYNTHETIC ANALOGUES OF MIGRASTATIN: MGSTA-5 and MGSTA-6 were potent inhibitors of canine mammary cancer cells migration and invasion. These data were obtained using the wound healing test, as well as trans-well migration and invasion assays. Furthermore, the treatment of cancer cells with the most effective compound (MGSTA-6 disturbed binding between filamentous F-actin and fascin1. Confocal microscopy analyses revealed that treatment with MGSTA-6 increased the presence of unbound fascin1 and reduced co-localization of F-actin and fascin1 in canine cancer cells. Most likely, actin filaments were not cross-linked by fascin1 and did not generate the typical filopodial architecture of actin filaments in response to the activity of MGSTA-6. Thus, administration of MGSTA-6 results in decreased formation of filopodia protrusions and stress fibres in canine mammary cancer cells, causing inhibition of cancer migration and invasion. CONCLUSION: Two synthetic migrastatin analogues (MGSTA-5 and MGSTA-6 were shown to be promising compounds for inhibition of cancer metastasis. They may have beneficial therapeutic effects in cancer therapy in dogs, especially in combination with other anticancer drugs

  6. Muscle Satellite Cells: Exploring the Basic Biology to Rule Them.

    Science.gov (United States)

    Almeida, Camila F; Fernandes, Stephanie A; Ribeiro Junior, Antonio F; Keith Okamoto, Oswaldo; Vainzof, Mariz

    2016-01-01

    Adult skeletal muscle is a postmitotic tissue with an enormous capacity to regenerate upon injury. This is accomplished by resident stem cells, named satellite cells, which were identified more than 50 years ago. Since their discovery, many researchers have been concentrating efforts to answer questions about their origin and role in muscle development, the way they contribute to muscle regeneration, and their potential to cell-based therapies. Satellite cells are maintained in a quiescent state and upon requirement are activated, proliferating, and fusing with other cells to form or repair myofibers. In addition, they are able to self-renew and replenish the stem pool. Every phase of satellite cell activity is highly regulated and orchestrated by many molecules and signaling pathways; the elucidation of players and mechanisms involved in satellite cell biology is of extreme importance, being the first step to expose the crucial points that could be modulated to extract the optimal response from these cells in therapeutic strategies. Here, we review the basic aspects about satellite cells biology and briefly discuss recent findings about therapeutic attempts, trying to raise questions about how basic biology could provide a solid scaffold to more successful use of these cells in clinics.

  7. Human Satellite Cell Transplantation and Regeneration from Diverse Skeletal Muscles

    Directory of Open Access Journals (Sweden)

    Xiaoti Xu

    2015-09-01

    Full Text Available Identification of human satellite cells that fulfill muscle stem cell criteria is an unmet need in regenerative medicine. This hurdle limits understanding how closely muscle stem cell properties are conserved among mice and humans and hampers translational efforts in muscle regeneration. Here, we report that PAX7 satellite cells exist at a consistent frequency of 2–4 cells/mm of fiber in muscles of the human trunk, limbs, and head. Xenotransplantation into mice of 50–70 fiber-associated, or 1,000–5,000 FACS-enriched CD56+/CD29+ human satellite cells led to stable engraftment and formation of human-derived myofibers. Human cells with characteristic PAX7, CD56, and CD29 expression patterns populated the satellite cell niche beneath the basal lamina on the periphery of regenerated fibers. After additional injury, transplanted satellite cells robustly regenerated to form hundreds of human-derived fibers. Together, these findings conclusively delineate a source of bona-fide endogenous human muscle stem cells that will aid development of clinical applications.

  8. Semaphorin 7A Promotes Chemokine-Driven Dendritic Cell Migration

    NARCIS (Netherlands)

    van Rijn, Anoek; Paulis, Leonie; te Riet, Joost; Vasaturo, Angela; Reinieren-Beeren, Inge; van der Schaaf, Alie; Kuipers, Arthur J.; Schulte, Luuk P.; Jongbloets, Bart C.; Pasterkamp, R. Jeroen; Figdor, Carl G.; van Spriel, Annemiek B.; Buschow, Sonja I.

    2016-01-01

    Dendritic cell (DC) migration is essential for efficient host defense against pathogens and cancer, as well as for the efficacy of DC-based immunotherapies. However, the molecules that induce the migratory phenotype of DCs are poorly defined. Based on a largescale proteome analysis of maturing DCs,

  9. Ginsenoside Rg1 promotes endothelial progenitor cell migration and proliferation

    Institute of Scientific and Technical Information of China (English)

    Ai-wu SHI; Xiao-bin WANG; Feng-xiang LU; Min-min ZHU; Xiang-qing KONG; Ke-jiang CAO

    2009-01-01

    Aim: To investigate the effect of ginsenoside Rgl on the migration, adhesion, proliferation, and VEGF expression of endothe-lial progenitor cells (EPCs).Methods: EPCs were isolated from human peripheral blood and incubated with different concentrations of ginsenoside Rgl (0.1, 0.5, 1.0, and 5.0 μmol/L) and vehicle controls. EPC migration was detected with a modified Boyden chamber assay. EPC adhesion was determined by counting adherent cells on fibronectin-coated culture dishes. EPC proliferation was analyzed with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. In vitro vasculogenesis was assayed using an in vitro vasculogenesis detection kit. A VEGF-ELISA kit was used to measure the amount of VEGF protein in the cell culture medium.Results: Ginsenoside Rgl promoted EPC adhesionp proliferation, migration and in vitro vasculogenesis in a dose- and time-dependent manner. Cell cycle analysis showed that 5.0 μmol/L of ginsenoside Rgl significantly increased the EPC prolifera-tive phase (S phase) and decreased the resting phase (G0/G1 phase). Ginsenoside Rgl increased vascular endothelial growth factor production.Conclusion: The results indicate that ginsenoside Rgl promotes proliferation, migration, adhesion and in vitro vasculogen-esis.

  10. Chemical amplifier, self-ignition mechanism, and amoeboid cell migration

    Science.gov (United States)

    Schienbein, M.; Gruler, H.

    1995-10-01

    The signal transduction chain of amoeboid migrating cells, such as human granulocytes, is approximated. Only the mean concentration of intracellular messenger molecules is considered. The weak cellular input signal originating from membrane-bound receptors occupied by molecules that stimulate migration steers a large flux of energy and mass. The strong second intracellular signal is produced by a chemical amplifier. Several functions are performed by this second intracellular signal: (i) the activation of the microfilaments (linear motor), (ii) the renewal of the membrane-bound receptors, and (iii) the alteration of the input characteristics of the chemical amplifier. The rate equation for the second messenger is derived. The solution of this machine equation is compared with experimental results. The chemokinetic dose-response curve, as well as a machine cycle, are predicted. A threshold concentration of the migration-stimulating molecules is predicted. At high concentrations, the cells are in an activated state with self-maintained oscillations of the second intracellular messenger, and at low concentrations, the cells are in an inactivated state without oscillations. The migration-stimulated cells are compared to a laser.

  11. STRIPAK components determine mode of cancer cell migration and metastasis

    DEFF Research Database (Denmark)

    Madsen, Chris D; Hooper, Steven; Tozluoglu, Melda;

    2015-01-01

    and MST4 kinases, which promote the co-localization of the contractile actomyosin machinery with the Ezrin/Radixin/Moesin family proteins by phosphorylating the inhibitors of PPP1CB, PPP1R14A-D. Using computational modelling, in vitro cell migration assays and in vivo breast cancer metastasis assays we...

  12. 25-Hydroxycholesterol promotes migration and invasion of lung adenocarcinoma cells.

    Science.gov (United States)

    Chen, Li; Zhang, Lishan; Xian, Guozhe; Lv, Yinping; Lin, Yanliang; Wang, Yibing

    2017-03-18

    25-hydroxycholesterol (25-HC) is enzymatically produced by cholesterol 25-hydorxylase in various organs and is involved in many processes, including lipid metabolism, inflammation and the immune response. However, the role of 25-HC in the migration and invasion of lung adenocarcinoma (ADC) cells remains largely unknown. In this study, we demonstrated that 0.1 μM 25-HC promoted ADC cell migration and invasion without affecting cell proliferation, especially after coculture with THP1-derived macrophages. Further investigation showed that 0.1 μM 25-HC significantly stimulated interleukin-1β (IL-1β) secretion in a coculture system and increased the expression of LXR and Snail. IL-1β also mimicked the effect of 25-HC. LXR knockdown notably blocked the 25-HC-induced Snail expression, migration and invasion in both the monoculture system and the coculture system, but it did not impact the effect of IL-1β, which suggested that IL-1β functioned in an LXR-independent manner. These results suggested that 25-HC promoted ADC cell migration and invasion in an LXR-dependent manner in the monoculture system but that in the coculture system, the 25-HC-induced IL-1β secretion enhanced the effect of 25-HC in an LXR-independent manner.

  13. Migrating glioma cells express stem cell markers and give rise to new tumors upon xenografting

    DEFF Research Database (Denmark)

    Munthe, Sune; Sørensen, Mia D; Thomassen, Mads

    2016-01-01

    -related genes and the HOX-gene list in migrating cells compared to spheroids. Determination of GBM molecular subtypes revealed that subtypes of spheroids and migrating cells were identical. In conclusion, migrating tumor cells preserve expression of stem cell markers and functional CSC characteristics. Since......Glioblastoma (GBM) is the most frequent and malignant brain tumor with an overall survival of only 14.6 months. Although these tumors are treated with surgery, radiation and chemotherapy, recurrence is inevitable. A critical population of tumor cells in terms of therapy, the so-called cancer stem...... cells (CSCs), has been identified in gliomas and many other cancers. These tumor cells have a stem cell-like phenotype and are suggested to be responsible for tumor growth, chemo- and radio-resistance as well as recurrence. However, functional evidence for migrating glioma cells having a stem cell...

  14. Single and collective cell migration: the mechanics of adhesions

    Science.gov (United States)

    De Pascalis, Chiara; Etienne-Manneville, Sandrine

    2017-01-01

    Chemical and physical properties of the environment control cell proliferation, differentiation, or apoptosis in the long term. However, to be able to move and migrate through a complex three-dimensional environment, cells must quickly adapt in the short term to the physical properties of their surroundings. Interactions with the extracellular matrix (ECM) occur through focal adhesions or hemidesmosomes via the engagement of integrins with fibrillar ECM proteins. Cells also interact with their neighbors, and this involves various types of intercellular adhesive structures such as tight junctions, cadherin-based adherens junctions, and desmosomes. Mechanobiology studies have shown that cell–ECM and cell–cell adhesions participate in mechanosensing to transduce mechanical cues into biochemical signals and conversely are responsible for the transmission of intracellular forces to the extracellular environment. As they migrate, cells use these adhesive structures to probe their surroundings, adapt their mechanical properties, and exert the appropriate forces required for their movements. The focus of this review is to give an overview of recent developments showing the bidirectional relationship between the physical properties of the environment and the cell mechanical responses during single and collective cell migration. PMID:28684609

  15. Collective cell migration: a physics perspective

    Science.gov (United States)

    Hakim, Vincent; Silberzan, Pascal

    2017-07-01

    Cells have traditionally been viewed either as independently moving entities or as somewhat static parts of tissues. However, it is now clear that in many cases, multiple cells coordinate their motions and move as collective entities. Well-studied examples comprise development events, as well as physiological and pathological situations. Different ex vivo model systems have also been investigated. Several recent advances have taken place at the interface between biology and physics, and have benefitted from progress in imaging and microscopy, from the use of microfabrication techniques, as well as from the introduction of quantitative tools and models. We review these interesting developments in quantitative cell biology that also provide rich examples of collective out-of-equilibrium motion.

  16. Mast cell progenitors: origin, development and migration to tissues.

    Science.gov (United States)

    Dahlin, Joakim S; Hallgren, Jenny

    2015-01-01

    Mast cells in tissues are developed from mast cell progenitors emerging from the bone marrow in a process highly regulated by transcription factors. Through the advancement of the multicolor flow cytometry technique, the mast cell progenitor population in the mouse has been characterized in terms of surface markers. However, only cell populations with enriched mast cell capability have been described in human. In naïve mice, the peripheral tissues have a constitutive pool of mast cell progenitors. Upon infections in the gut and in allergic inflammation in the lung, the local mast cell progenitor numbers increase tremendously. This review focuses on the origin and development of mast cell progenitors. Furthermore, the evidences for cells and molecules that govern the migration of these cells in mice in vivo are described.

  17. Histone modifications associated with cancer cell migration and invasion.

    Science.gov (United States)

    Hieda, Miki; Matsuura, Nariaki; Kimura, Hiroshi

    2015-01-01

    Genome-wide aberrant histone modifications are present in a wide range of cancers, and they are associated with carcinogenesis and cancer progression. Aberrant histone modification patterns affect transcriptional regulation, chromosome stability, chromatin structure, chromatin remodeling, and DNA methylation; furthermore, these patterns can predict clinical outcome in many types of cancer. The main cause of poor clinical outcome is metastasis, which is strongly associated with tissue invasion at the primary tumor site. Invasion of cancer cells into surrounding tissue and the vasculature is an important initial step in tumor metastasis, and cell migration is a critical requirement for metastasis. Here, we describe the advantages of detecting global histone modifications by immunohistochemical analysis and provide a collection of protocols for assaying cell migration, invasion, and cell-extracellular matrix adhesion in vitro.

  18. Seasonal distributions and migrations of Northwest Atlantic swordfish: inferences from integration of pop-up satellite archival tagging studies.

    Science.gov (United States)

    Neilson, John D; Loefer, Josh; Prince, Eric D; Royer, François; Calmettes, Beatriz; Gaspar, Philippe; Lopez, Rémy; Andrushchenko, Irene

    2014-01-01

    Data sets from three laboratories conducting studies of movements and migrations of Atlantic swordfish (Xiphias gladius) using pop-up satellite archival tags were pooled, and processed using a common methodology. From 78 available deployments, 38 were selected for detailed examination based on deployment duration. The points of deployment ranged from southern Newfoundland to the Straits of Florida. The aggregate data comprise the most comprehensive information describing migrations of swordfish in the Atlantic. Challenges in using data from different tag manufacturers are discussed. The relative utility of geolocations obtained with light is compared with results derived from temperature information for this deep-diving species. The results show that fish tagged off North America remain in the western Atlantic throughout their deployments. This is inconsistent with the model of stock structure used in assessments conducted by the International Commission for the Conservation of Atlantic Tunas, which assumes that fish mix freely throughout the North Atlantic.

  19. New insights into directed cell migration: characteristics and mechanisms.

    Science.gov (United States)

    Gruler, H

    1995-01-01

    The present article describes how it is possible to elucidate the essential cellular machines controlling directed migration. Investigations are performed with cells like granulocytes, fibroblasts or neural crest cells and these cells are found to contain two independent types of machines, a steerer (controller without feedback) for the speed and an automatic controller (controller with feedback) for the angle of migration. The first intracellular signal is the distribution of membrane bound receptors occupied by kinesis stimulating molecules from the extracellular space. Motile force is produced by a linear motor supplied by the chemically amplified first intracellular signal (total number of occupied receptors). When properties of the cellular steering device are investigated, results show the angle of migration to be corrected by an automatic controller and an asymmetric distribution of occupied receptors to be the first intracellular signal for directed migration. Properties of the goal-seeking device are also investigated. As in many different types of technical machines, the cellular machinery operates in a cyclic manner which in the case of granulocytes a measuring cycle of 8 s and a response cycle of approximately 60 s. These cellular machines may be understood in terms of a self-ignition mechanism where the renewal of membrane bound receptors is the essential step.

  20. Migration Phenotype of Brain-Cancer Cells Predicts Patient Outcomes

    Directory of Open Access Journals (Sweden)

    Chris L. Smith

    2016-06-01

    Full Text Available Glioblastoma multiforme is a heterogeneous and infiltrative cancer with dismal prognosis. Studying the migratory behavior of tumor-derived cell populations can be informative, but it places a high premium on the precision of in vitro methods and the relevance of in vivo conditions. In particular, the analysis of 2D cell migration may not reflect invasion into 3D extracellular matrices in vivo. Here, we describe a method that allows time-resolved studies of primary cell migration with single-cell resolution on a fibrillar surface that closely mimics in vivo 3D migration. We used this platform to screen 14 patient-derived glioblastoma samples. We observed that the migratory phenotype of a subset of cells in response to platelet-derived growth factor was highly predictive of tumor location and recurrence in the clinic. Therefore, migratory phenotypic classifiers analyzed at the single-cell level in a patient-specific way can provide high diagnostic and prognostic value for invasive cancers.

  1. Migration of amoeba cells in an electric field

    Science.gov (United States)

    Guido, Isabella; Bodenschatz, Eberhard

    2015-03-01

    Exogenous and endogenous electric fields play a role in cell physiology as a guiding mechanism for the orientation and migration of cells. Electrotaxis of living cells has been observed for several cell types, e.g. neurons, fibroblasts, leukocytes, neural crest cells, cancer cells. Dictyostelium discoideum (Dd), an intensively investigated chemotactic model organism, also exhibits a strong electrotactic behavior moving toward the cathode under the influence of electric fields. Here we report experiments on the effects of DC electric fields on the directional migration of Dd cells. We apply the electric field to cells seeded into microfluidic devices equipped with agar bridges to avoid any harmful effects of the electric field on the cells (ions formation, pH changes, etc.) and a constant flow to prevent the build-up of chemical gradient that elicits chemotaxis. Our results show that the cells linearly increase their speed over time when a constant electric field is applied for a prolonged duration (2 hours). This novel phenomenon cannot be attributed to mechanotaxis as the drag force of the electroosmotic flow is too small to produce shear forces that can reorient cells. It is independent of the cellular developmental stage and to our knowledge, it was not observed in chemotaxis. This work is supported by MaxSynBio project of the Max Planck Society.

  2. Periodic migration in a physical model of cells on micropatterns

    Science.gov (United States)

    Camley, Brian A.; Zhao, Yanxiang; Li, Bo; Levine, Herbert; Rappel, Wouter-Jan

    2013-01-01

    We extend a model for the morphology and dynamics of a crawling eukaryotic cell to describe cells on micropatterned substrates. This model couples cell morphology, adhesion, and cytoskeletal flow in response to active stresses induced by actin and myosin. We propose that protrusive stresses are only generated where the cell adheres, leading to the cell's effective confinement to the pattern. Consistent with experimental results, simulated cells exhibit a broad range of behaviors, including steady motion, turning, bipedal motion, and periodic migration, in which the cell crawls persistently in one direction before reversing periodically. We show that periodic motion emerges naturally from the coupling of cell polarization to cell shape by reducing the model to a simplified one-dimensional form that can be understood analytically. PMID:24160631

  3. [Molecular mechanism maintaining muscle satellite cells and the roles in sarcopenia.

    Science.gov (United States)

    Takemoto, Yusei; Fukada, So-Ichiro

    2017-01-01

    Skeletal muscle has its stem cell named satellite cell. The absence of satellite cells does not allow muscle regeneration, it is unquestionable that satellite cell is indispensable for muscle regeneration processes. A certain number of satellite cells appear to be necessary for the successful muscle regeneration, meaning the maintenance of the satellite cells is essential for the functional homeostasis of skeletal muscle. Recent studies have revealed the molecular mechanism underlying satellite cell maintenance in a steady state. A loss of those molecules responsible for the maintenance often results in decreased satellite cell pool and reduced regeneration ability. On the other hand, the contribution of satellite cells to muscle hypertrophy or aged-related atrophy(sarcopenia)is controversial. In this review, we will introduce the molecules that regulate satellite cells homeostasis in the dormant state and then further discuss the recent results on the roles of satellite cell in sarcopenia.

  4. Fucan effect on CHO cell proliferation and migration.

    Science.gov (United States)

    Nobre, Leonardo Thiago Duarte Barreto; Vidal, Arthur Anthunes Jacome; Almeida-Lima, Jailma; Oliveira, Ruth Medeiros; Paredes-Gamero, Edgar Jean; Medeiros, Valquiria Pereira; Trindade, Edvaldo Silva; Franco, Celia Regina Cavichiolo; Nader, Helena Bonciani; Rocha, Hugo Alexandre Oliveira

    2013-10-15

    Fucan is a term used to denominate sulfated L-fucose rich polysaccharides. Here, a heterofucan, named fucan B, was extracted from the Spatoglossum schröederi seaweed. This 21.5 kDa galactofucan inhibited CHO-K1 proliferation and migration when fibronectin was the substrate. Fucan B derivatives revealed that such effects depend on their degree of sulfation. Fucan B did not induce cell death, but promoted G1 cell cycle arrest. Western blotting and flow cytometry analysis suggest that fucan B binds to fibronectin and activates integrin, mainly integrin α5β1, which induces FAK/RAS/MEK/ERK activation. FAK activation inhibits CHO-K1 migration on fibronectin and ERK blocks cell cycle progression. This study indicates that fucan B could be applied in developing new antitumor drugs.

  5. Ion channels in control of pancreatic stellate cell migration

    Science.gov (United States)

    Storck, Hannah; Hild, Benedikt; Schimmelpfennig, Sandra; Sargin, Sarah; Nielsen, Nikolaj; Zaccagnino, Angela; Budde, Thomas; Novak, Ivana; Kalthoff, Holger; Schwab, Albrecht

    2017-01-01

    Pancreatic stellate cells (PSCs) play a critical role in the progression of pancreatic ductal adenocarcinoma (PDAC). Once activated, PSCs support proliferation and metastasis of carcinoma cells. PSCs even co-metastasise with carcinoma cells. This requires the ability of PSCs to migrate. In recent years, it has been established that almost all “hallmarks of cancer” such as proliferation or migration/invasion also rely on the expression and function of ion channels. So far, there is only very limited information about the function of ion channels in PSCs. Yet, there is growing evidence that ion channels in stromal cells also contribute to tumor progression. Here we investigated the function of KCa3.1 channels in PSCs. KCa3.1 channels are also found in many tumor cells of different origin. We revealed the functional expression of KCa3.1 channels by means of Western blot, immunofluorescence and patch clamp analysis. The impact of KCa3.1 channel activity on PSC function was determined with live-cell imaging and by measuring the intracellular Ca2+ concentration ([Ca2+]i). KCa3.1 channel blockade or knockout prevents the stimulation of PSC migration and chemotaxis by reducing the [Ca2+]i and calpain activity. KCa3.1 channels functionally cooperate with TRPC3 channels that are upregulated in PDAC stroma. Knockdown of TRPC3 channels largely abolishes the impact of KCa3.1 channels on PSC migration. In summary, our results clearly show that ion channels are crucial players in PSC physiology and pathophysiology. PMID:27903970

  6. CYR61 downregulation reduces osteosarcoma cell invasion, migration, and metastasis.

    Science.gov (United States)

    Fromigue, Olivia; Hamidouche, Zahia; Vaudin, Pascal; Lecanda, Fernando; Patino, Ana; Barbry, Pascal; Mari, Bernard; Marie, Pierre J

    2011-07-01

    Osteosarcoma is the most common primary tumor of bone. The rapid development of metastatic lesions and resistance to chemotherapy remain major mechanisms responsible for the failure of treatments and the poor survival rate for patients. We showed previously that the HMGCoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase inhibitor statin exhibits antitumoral effects on osteosarcoma cells. Here, using microarray analysis, we identify Cyr61 as a new target of statins. Transcriptome and molecular analyses revealed that statins downregulate Cyr61 expression in human and murine osteosarcoma cells. Cyr61 silencing in osteosarcoma cell lines enhanced cell death and reduced cell migration and cell invasion compared with parental cells, whereas Cyr61 overexpression had opposite effects. Cyr61 expression was evaluated in 231 tissue cores from osteosarcoma patients. Tissue microarray analysis revealed that Cyr61 protein expression was higher in human osteosarcoma than in normal bone tissue and was further increased in metastatic tissues. Finally, tumor behavior and metastasis occurrence were analyzed by intramuscular injection of modified osteosarcoma cells into BALB/c mice. Cyr61 overexpression enhanced lung metastasis development, whereas cyr61 silencing strongly reduced lung metastases in mice. The results reveal that cyr61 expression increases with tumor grade in human osteosarcoma and demonstrate that cyr61 silencing inhibits in vitro osteosarcoma cell invasion and migration as well as in vivo lung metastases in mice. These data provide a novel molecular target for therapeutic intervention in metastatic osteosarcoma. Copyright © 2011 American Society for Bone and Mineral Research.

  7. Silencing of directional migration in roundabout4 knockdown endothelial cells

    Directory of Open Access Journals (Sweden)

    Roberts David D

    2008-11-01

    Full Text Available Abstract Background Roundabouts are axon guidance molecules that have recently been identified to play a role in vascular guidance as well. In this study, we have investigated gene knockdown analysis of endothelial Robos, in particular roundabout 4 (robo4, the predominant Robo in endothelial cells using small interfering RNA technology in vitro. Results Robo1 and Robo4 knockdown cells display distinct activity in endothelial cell migration assay. The knockdown of robo4 abrogated the chemotactic response of endothelial cells to serum but enhanced a chemokinetic response to Slit2, while robo1 knockdown cells do not display chemotactic response to serum or VEGF. Robo4 knockdown endothelial cells unexpectedly show up regulation of Rho GTPases. Zebrafish Robo4 rescues both Rho GTPase homeostasis and serum reduced chemotaxis in robo4 knockdown cells. Robo1 and Robo4 interact and share molecules such as Slit2, Mena and Vilse, a Cdc42-GAP. In addition, this study mechanistically implicates IRSp53 in the signaling nexus between activated Cdc42 and Mena, both of which have previously been shown to be involved with Robo4 signaling in endothelial cells. Conclusion This study identifies specific components of the Robo signaling apparatus that work together to guide directional migration of endothelial cells.

  8. On the Role of PDZ Domain-Encoding Genes in Drosophila Border Cell Migration

    OpenAIRE

    Aranjuez, George; Kudlaty, Elizabeth; Longworth, Michelle S; McDonald, Jocelyn A.

    2012-01-01

    Cells often move as collective groups during normal embryonic development and wound healing, although the mechanisms governing this type of migration are poorly understood. The Drosophila melanogaster border cells migrate as a cluster during late oogenesis and serve as a powerful in vivo genetic model for collective cell migration. To discover new genes that participate in border cell migration, 64 out of 66 genes that encode PDZ domain-containing proteins were systematically targeted by in v...

  9. SENP1 regulates cell migration and invasion in neuroblastoma.

    Science.gov (United States)

    Xiang-Ming, Yan; Zhi-Qiang, Xu; Ting, Zhang; Jian, Wang; Jian, Pan; Li-Qun, Yuan; Ming-Cui, Fu; Hong-Liang, Xia; Xu, Cao; Yun, Zhou

    2016-05-01

    Neuroblastoma (NB) is an embryonic solid tumor derived from precursor cells of the sympathetic nervous system, and accounts for 11% of childhood cancers and around 15% of cancer deaths in children. SUMOylation and deSUMOylation are dynamic mechanisms regulating a spectrum of protein activities. The SUMO proteases (SENP) remove SUMO conjugate from proteins, and their expression is deregulated in diverse cancers. However, nothing is known about the role of SENPs in NBL. In the present study, we found that SENP1 expression was significantly high in metastatic NB tissues compared with primary NB tissues. Overexpression of SENP1 promoted NB cells migration and invasion. Inhibition of SENP1 could significantly suppress NB cell migration and invasion. Moreover, we found that SENP1 could regulate the expression of CDH1, MMP9, and MMP2. In summary, the data presented here indicate a significant role of SENP1 in the regulation of cell migration and invasion in NB and suppress SENP1 expression as promising candidates for novel treatment strategies of NB.

  10. Nifedipine promotes the proliferation and migration of breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Dong-Qing Guo

    Full Text Available Nifedipine is widely used as a calcium channel blocker (CCB to treat angina and hypertension,but it is controversial with respect the risk of stimulation of cancers. In this study, we demonstrated that nifedipine promoted the proliferation and migration of breast cancer cells both invivo and invitro. However, verapamil, another calcium channel blocker, didn't exert the similar effects. Nifedipine and high concentration KCl failed to alter the [Ca2+]i in MDA-MB-231 cells, suggesting that such nifedipine effect was not related with calcium channel. Moreover, nifedipine decreased miRNA-524-5p, resulting in the up-regulation of brain protein I3 (BRI3. Erk pathway was consequently activated and led to the proliferation and migration of breast cancer cells. Silencing BRI3 reversed the promoting effect of nifedipine on the breast cancer. In a summary, nifedipine stimulated the proliferation and migration of breast cancer cells via the axis of miRNA-524-5p-BRI3-Erk pathway independently of its calcium channel-blocking activity. Our findings highlight that nifedipine but not verapamil is conducive for breast cancer growth and metastasis, urging that the caution should be taken in clinic to prescribe nifedipine to women who suffering both hypertension and breast cancer, and hypertension with a tendency in breast cancers.

  11. Molecular aspects of tumor cell migration and invasion

    Directory of Open Access Journals (Sweden)

    Giuseppina Bozzuto

    2010-03-01

    Full Text Available Cell migration and invasion are crucial steps in many physiological events. However, they are also implicated in the physiopathology of many diseases, such as cancer. To spread through the tissues, tumor cells use mechanisms that involve several molecular actors: adhesion receptor families, receptor tyrosine kinases, cytoskeleton proteins, adapter and signalling proteins interplay in a complex scenario. The balance of cellular signals for proliferation and survival responses also regulates migratory behaviours of tumor cells. To complicate the scene of crime drug resistance players can interfere thus worsening this delicate situation. The complete understanding of this molecular jungle is an impossible mission: some molecular aspects are reviewed in this paper.

  12. Angiotensin II facilitates breast cancer cell migration and metastasis.

    Directory of Open Access Journals (Sweden)

    Sylvie Rodrigues-Ferreira

    Full Text Available Breast cancer metastasis is a leading cause of death by malignancy in women worldwide. Efforts are being made to further characterize the rate-limiting steps of cancer metastasis, i.e. extravasation of circulating tumor cells and colonization of secondary organs. In this study, we investigated whether angiotensin II, a major vasoactive peptide both produced locally and released in the bloodstream, may trigger activating signals that contribute to cancer cell extravasation and metastasis. We used an experimental in vivo model of cancer metastasis in which bioluminescent breast tumor cells (D3H2LN were injected intra-cardiacally into nude mice in order to recapitulate the late and essential steps of metastatic dissemination. Real-time intravital imaging studies revealed that angiotensin II accelerates the formation of metastatic foci at secondary sites. Pre-treatment of cancer cells with the peptide increases the number of mice with metastases, as well as the number and size of metastases per mouse. In vitro, angiotensin II contributes to each sequential step of cancer metastasis by promoting cancer cell adhesion to endothelial cells, trans-endothelial migration and tumor cell migration across extracellular matrix. At the molecular level, a total of 102 genes differentially expressed following angiotensin II pre-treatment were identified by comparative DNA microarray. Angiotensin II regulates two groups of connected genes related to its precursor angiotensinogen. Among those, up-regulated MMP2/MMP9 and ICAM1 stand at the crossroad of a network of genes involved in cell adhesion, migration and invasion. Our data suggest that targeting angiotensin II production or action may represent a valuable therapeutic option to prevent metastatic progression of invasive breast tumors.

  13. Angiotensin Converting Enzyme Regulates Cell Proliferation and Migration

    Science.gov (United States)

    Carvalho, Clarissa Coelho; Florentino, Rodrigo Machado; França, Andressa; Matias, Eveline; Guimarães, Paola Bianchi; Batista, Carolina; Freire, Valder; Carmona, Adriana Karaoglanovic; Pesquero, João Bosco; de Paula, Ana Maria; Foureaux, Giselle; Leite, Maria de Fatima

    2016-01-01

    Background The angiotensin-I converting enzyme (ACE) plays a central role in the renin-angiotensin system, acting by converting the hormone angiotensin-I to the active peptide angiotensin-II (Ang-II). More recently, ACE was shown to act as a receptor for Ang-II, and its expression level was demonstrated to be higher in melanoma cells compared to their normal counterparts. However, the function that ACE plays as an Ang-II receptor in melanoma cells has not been defined yet. Aim Therefore, our aim was to examine the role of ACE in tumor cell proliferation and migration. Results We found that upon binding to ACE, Ang-II internalizes with a faster onset compared to the binding of Ang-II to its classical AT1 receptor. We also found that the complex Ang-II/ACE translocates to the nucleus, through a clathrin-mediated process, triggering a transient nuclear Ca2+ signal. In silico studies revealed a possible interaction site between ACE and phospholipase C (PLC), and experimental results in CHO cells, demonstrated that the β3 isoform of PLC is the one involved in the Ca2+ signals induced by Ang-II/ACE interaction. Further studies in melanoma cells (TM-5) showed that Ang-II induced cell proliferation through ACE activation, an event that could be inhibited either by ACE inhibitor (Lisinopril) or by the silencing of ACE. In addition, we found that stimulation of ACE by Ang-II caused the melanoma cells to migrate, at least in part due to decreased vinculin expression, a focal adhesion structural protein. Conclusion ACE activation regulates melanoma cell proliferation and migration. PMID:27992423

  14. FH535 inhibited migration and growth of breast cancer cells.

    Science.gov (United States)

    Iida, Joji; Dorchak, Jesse; Lehman, John R; Clancy, Rebecca; Luo, Chunqing; Chen, Yaqin; Somiari, Stella; Ellsworth, Rachel E; Hu, Hai; Mural, Richard J; Shriver, Craig D

    2012-01-01

    There is substantial evidence indicating that the WNT signaling pathway is activated in various cancer cell types including breast cancer. Previous studies reported that FH535, a small molecule inhibitor of the WNT signaling pathway, decreased growth of cancer cells but not normal fibroblasts, suggesting this pathway plays a role in tumor progression and metastasis. In this study, we tested FH535 as a potential inhibitor for malignant phenotypes of breast cancer cells including migration, invasion, and growth. FH535 significantly inhibited growth, migration, and invasion of triple negative (TN) breast cancer cell lines (MDA-MB231 and HCC38) in vitro. We demonstrate that FH535 was a potent growth inhibitor for TN breast cancer cell lines (HCC38 and MDA-MB-231) but not for other, non-TN breast cancer cell lines (MCF-7, T47D or SK-Br3) when cultured in three dimensional (3D) type I collagen gels. Western blotting analyses suggest that treatment of MDA-MB-231 cells with FH535 markedly inhibited the expression of NEDD9 but not activations of FAK, Src, or downstream targets such as p38 and Erk1/2. We demonstrated that NEDD9 was specifically associated with CSPG4 but not with β1 integrin or CD44 in MDA-MB-231 cells. Analyses of gene expression profiles in breast cancer tissues suggest that CSPG4 expression is higher in Basal-type breast cancers, many of which are TN, than any other subtypes. These results suggest not only a mechanism for migration and invasion involving the canonical WNT-signaling pathways but also novel strategies for treating patients who develop TN breast cancer.

  15. FH535 inhibited migration and growth of breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Joji Iida

    Full Text Available There is substantial evidence indicating that the WNT signaling pathway is activated in various cancer cell types including breast cancer. Previous studies reported that FH535, a small molecule inhibitor of the WNT signaling pathway, decreased growth of cancer cells but not normal fibroblasts, suggesting this pathway plays a role in tumor progression and metastasis. In this study, we tested FH535 as a potential inhibitor for malignant phenotypes of breast cancer cells including migration, invasion, and growth. FH535 significantly inhibited growth, migration, and invasion of triple negative (TN breast cancer cell lines (MDA-MB231 and HCC38 in vitro. We demonstrate that FH535 was a potent growth inhibitor for TN breast cancer cell lines (HCC38 and MDA-MB-231 but not for other, non-TN breast cancer cell lines (MCF-7, T47D or SK-Br3 when cultured in three dimensional (3D type I collagen gels. Western blotting analyses suggest that treatment of MDA-MB-231 cells with FH535 markedly inhibited the expression of NEDD9 but not activations of FAK, Src, or downstream targets such as p38 and Erk1/2. We demonstrated that NEDD9 was specifically associated with CSPG4 but not with β1 integrin or CD44 in MDA-MB-231 cells. Analyses of gene expression profiles in breast cancer tissues suggest that CSPG4 expression is higher in Basal-type breast cancers, many of which are TN, than any other subtypes. These results suggest not only a mechanism for migration and invasion involving the canonical WNT-signaling pathways but also novel strategies for treating patients who develop TN breast cancer.

  16. MiR-155 inhibits cell migration of human cardiomyocyte progenitor cells (hCMPCs) via targeting of MMP-16

    NARCIS (Netherlands)

    Liu, Jia; van Mil, Alain; Aguor, Eissa N. E.; Siddiqi, Sailay; Vrijsen, Krijn; Jaksani, Sridevi; Metz, Corina; Zhao, Jiajun; Strijkers, Gustav J.; Doevendans, Pieter A.; Sluijter, Joost P. G.

    2012-01-01

    Undesired cell migration after targeted cell transplantation potentially limits beneficial effects for cardiac regeneration. MicroRNAs are known to be involved in several cellular processes, including cell migration. Here, we attempt to reduce human cardiomyocyte progenitor cell (hCMPC) migration vi

  17. Dock-family exchange factors in cell migration and disease.

    Science.gov (United States)

    Gadea, Gilles; Blangy, Anne

    2014-10-01

    Dock family proteins are evolutionary conserved exchange factors for the Rho GTPases Rac and Cdc42. There are 11 Dock proteins in mammals, named Dock1 (or Dock180) to Dock11 that play different cellular functions. In particular, Dock proteins regulate actin cytoskeleton, cell adhesion and migration. Not surprisingly, members of the Dock family have been involved in various pathologies, including cancer and defects in the central nervous and immune systems. This review proposes an update of the recent findings regarding the function of Dock proteins, focusing on their role in the control of cell migration and invasion and the consequences in human diseases. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. A possible new focus for stroke treatment - migrating stem cells.

    Science.gov (United States)

    Sullivan, Robert; Duncan, Kelsey; Dailey, Travis; Kaneko, Yuji; Tajiri, Naoki; Borlongan, Cesario V

    2015-07-01

    Stroke is a leading cause of mortality in the US. More so, its infliction often leaves patients with lasting morbidity and deficits. Ischemic stroke comprises nearly 90% of incidents and the majority of medical treatment aims at reestablishing perfusion and preventing recurrence. Long-term options for neurorestoration are limited by the infancy of their innovative approach. Accumulating evidence suggests the therapeutic potential of stem cells in neurorestoration, however, proper stem cell migration remains a challenge in translating stem cell therapy from the laboratory to the clinic. In this paper, we propose the role that exogenous stem cell transplantation may serve in facilitating the migration of endogenous stem cells to the site of injury, an idea termed 'biobridge'. Recent research in the field of traumatic brain injury has provided a foundational understanding that, through the use of exogenous stem cells, native tissue architecture may be manipulated by proteinases to allow better communication between the endogenous sites of neural stem cells and the regions of injury. There is still much to be learned about these mechanisms, though it is the devastating nature of stroke that necessitates continued research into the prospective therapeutic potential of this novel approach.

  19. Novel interactions between erythroblast macrophage protein and cell migration.

    Science.gov (United States)

    Javan, Gulnaz T; Can, Ismail; Yeboah, Fred; Lee, Youngil; Soni, Shivani

    2016-09-01

    Erythroblast macrophage protein is a novel protein known to mediate attachment of erythroid cells to macrophages to form erythroblastic islands in bone marrow during erythropoiesis. Emp-null macrophages are small with round morphologies, and lack cytoplasmic projections which imply immature structure. The role of Emp in macrophage development and function is not fully elucidated. Macrophages perform varied functions (e.g. homeostasis, erythropoiesis), and are implicated in numerous pathophysiological conditions such as cellular malignancy. The objective of the current study is to investigate the interaction of Emp with cytoskeletal- and cell migration-associated proteins involved in macrophage functions. A short hairpin RNA lentiviral system was use to down-regulate the expression of Emp in macrophage cells. A cell migration assay revealed that the relocation of macrophages was significantly inhibited when Emp expression was decreased. To further analyze changes in gene expression related to cell motility, PCR array was performed by down-regulating Emp expression. The results indicated that expression of mitogen-activated protein kinase 1 and thymoma viral proto-oncogene 1 were significantly higher when Emp was down-regulated. The results implicate Emp in abnormal cell motility, thus, warrants to assess its role in cancer where tumor cell motility is required for invasion and metastasis.

  20. Rac activation by the T-cell receptor inhibits T cell migration.

    Directory of Open Access Journals (Sweden)

    Eva Cernuda-Morollón

    Full Text Available BACKGROUND: T cell migration is essential for immune responses and inflammation. Activation of the T-cell receptor (TCR triggers a migration stop signal to facilitate interaction with antigen-presenting cells and cell retention at inflammatory sites, but the mechanisms responsible for this effect are not known. METHODOLOGY/PRINCIPAL FINDINGS: Migrating T cells are polarized with a lamellipodium at the front and uropod at the rear. Here we show that transient TCR activation induces prolonged inhibition of T-cell migration. TCR pre-activation leads to cells with multiple lamellipodia and lacking a uropod even after removal of the TCR signal. A similar phenotype is induced by expression of constitutively active Rac1, and TCR signaling activates Rac1. TCR signaling acts via Rac to reduce phosphorylation of ezrin/radixin/moesin proteins, which are required for uropod formation, and to increase stathmin phosphorylation, which regulates microtubule stability. T cell polarity and migration is partially restored by inhibiting Rac or by expressing constitutively active moesin. CONCLUSIONS/SIGNIFICANCE: We propose that transient TCR signaling induces sustained inhibition of T cell migration via Rac1, increased stathmin phosphorylation and reduced ERM phosphorylation which act together to inhibit T-cell migratory polarity.

  1. Rho GTPases and regulation of cell migration and polarization in human corneal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Aihua Hou

    Full Text Available PURPOSE: Epithelial cell migration is required for regeneration of tissues and can be defective in a number of ocular surface diseases. This study aimed to determine the expression pattern of Rho family small G-proteins in human corneal epithelial cells to test their requirement in directional cell migration. METHODS: Rho family small G-protein expression was assessed by reverse transcription-polymerase chain reaction. Dominant-inhibitory constructs encoding Rho proteins or Rho protein targeting small interfering RNA were transfected into human corneal epithelial large T antigen cells, and wound closure rate were evaluated by scratch wounding assay, and a complementary non-traumatic cell migration assay. Immunofluorescence staining was performed to study cell polarization and to assess Cdc42 downstream effector. RESULTS: Cdc42, Chp, Rac1, RhoA, TC10 and TCL were expressed in human corneal epithelial cells. Among them, Cdc42 and TCL were found to significantly affect cell migration in monolayer scratch assays. These results were confirmed through the use of validated siRNAs directed to Cdc42 and TCL. Scramble siRNA transfected cells had high percentage of polarized cells than Cdc42 or TCL siRNA transfected cells at the wound edge. We showed that the Cdc42-specific effector p21-activated kinase 4 localized predominantly to cell-cell junctions in cell monolayers, but failed to translocate to the leading edge in Cdc42 siRNA transfected cells after monolayer wounding. CONCLUSION: Rho proteins expressed in cultured human corneal epithelial cells, and Cdc42, TCL facilitate two-dimensional cell migration in-vitro. Although silencing of Cdc42 and TCL did not noticeably affect the appearance of cell adhesions at the leading edge, the slower migration of these cells indicates both GTP-binding proteins play important roles in promoting cell movement of human corneal epithelial cells.

  2. Common mechanisms regulating cell cortex properties during cell division and cell migration.

    Science.gov (United States)

    Roubinet, Chantal; Tran, Phong T; Piel, Matthieu

    2012-11-01

    Single cell morphogenesis results from a balance of forces involving internal pressure (also called turgor pressure in plants and fungi) and the plastic and dynamic outer shell of the cell. Dominated by the cell wall in plants and fungi, mechanical properties of the outer shell of animal cells arise from the cell cortex, which is mostly composed of the plasma membrane (and membrane proteins) and the underlying meshwork of actin filaments and myosin motors (and associated proteins). In this review, following Bray and White [1988; Science 239:883-889], we draw a parallel between the regulation of the cell cortex during cell division and cell migration in animal cells. Starting from the similarities in shape changes and underlying mechanical properties, we further propose that the analogy between cell division and cell migration might run deeper, down to the basic molecular mechanisms driving cell cortex remodeling. We focus our attention on how an heterogeneous and dynamic cortex can be generated to allow cell shape changes while preserving cell integrity.

  3. STRIPAK components determine mode of cancer cell migration and metastasis

    Science.gov (United States)

    Madsen, Chris D.; Hooper, Steven; Tozluoglu, Melda; Bruckbauer, Andreas; Fletcher, Georgina; Erler, Janine T.; Bates, Paul A.; Thompson, Barry; Sahai, Erik

    2017-01-01

    The contractile actomyosin cytoskeleton and its connection to the plasma membrane are critical for control of cell shape and migration. We identify three STRIPAK complex components, FAM40A, FAM40B, and STRN3, as regulators of the actomyosin cortex. We show that FAM40A negatively regulates the MST3 and MST4 kinases, which promote the co-localisation of the contractile actomyosin machinery with the Ezrin/Radixin/Moesin family proteins by phosphorylating the inhibitors of PPP1CB, PPP1R14A-D. Using computational modelling, in vitro cell migration assays and in vivo breast cancer metastasis assays we demonstrate that co-localisation of contractile activity and actin-plasma membrane linkage reduces cell speed on planar surfaces, but favours migration in confined environments similar to those observed in vivo. We further show that FAM40B mutations found in human tumours uncouple it from PP2A and enable it to drive a contractile phenotype, which may underlie its role in human cancer. PMID:25531779

  4. Methylene blue modulates transendothelial migration of peripheral blood cells.

    Directory of Open Access Journals (Sweden)

    Isabella Werner

    Full Text Available Vasoplegia is a severe complication after cardiac surgery. Within the last years the administration of nitric oxide synthase inhibitor methylene blue (MB became a new therapeutic strategy. Our aim was to investigate the role of MB on transendothelial migration of circulating blood cells, the potential role of cyclic cGMP, eNOS and iNOS in this process, and the influence of MB on endothelial cell apoptosis. Human vascular endothelial cells (HuMEC-1 were treated for 30 minutes or 2 hours with different concentrations of MB. Inflammation was mimicked by LPS stimulation prior and after MB. Transmigration of PBMCs and T-Lymphocytes through the treated endothelial cells was investigated. The influence of MB upon the different subsets of PBMCs (Granulocytes, T- and B-Lymphocytes, and Monocytes was assessed after transmigration by means of flow-cytometry. The effect of MB on cell apoptosis was evaluated using Annexin-V and Propidium Iodide stainings. Analyses of the expression of cyclic cGMP, eNOS and iNOS were performed by means of RT-PCR and Western Blot. Results were analyzed using unpaired Students T-test. Analysis of endothelial cell apoptosis by MB indicated a dose-dependent increase of apoptotic cells. We observed time- and dose-dependent effects of MB on transendothelial migration of PBMCs. The prophylactic administration of MB led to an increase of transendothelial migration of PBMCs but not Jurkat cells. Furthermore, HuMEC-1 secretion of cGMP correlated with iNOS expression after MB administration but not with eNOS expression. Expression of these molecules was reduced after MB administration at protein level. This study clearly reveals that endothelial response to MB is dose- and especially time-dependent. MB shows different effects on circulating blood cell-subtypes, and modifies the release patterns of eNOS, iNOS, and cGMP. The transendothelial migration is modulated after treatment with MB. Furthermore, MB provokes apoptosis of endothelial

  5. Methylene blue modulates transendothelial migration of peripheral blood cells.

    Science.gov (United States)

    Werner, Isabella; Guo, Fengwei; Bogert, Nicolai V; Stock, Ulrich A; Meybohm, Patrick; Moritz, Anton; Beiras-Fernandez, Andres

    2013-01-01

    Vasoplegia is a severe complication after cardiac surgery. Within the last years the administration of nitric oxide synthase inhibitor methylene blue (MB) became a new therapeutic strategy. Our aim was to investigate the role of MB on transendothelial migration of circulating blood cells, the potential role of cyclic cGMP, eNOS and iNOS in this process, and the influence of MB on endothelial cell apoptosis. Human vascular endothelial cells (HuMEC-1) were treated for 30 minutes or 2 hours with different concentrations of MB. Inflammation was mimicked by LPS stimulation prior and after MB. Transmigration of PBMCs and T-Lymphocytes through the treated endothelial cells was investigated. The influence of MB upon the different subsets of PBMCs (Granulocytes, T- and B-Lymphocytes, and Monocytes) was assessed after transmigration by means of flow-cytometry. The effect of MB on cell apoptosis was evaluated using Annexin-V and Propidium Iodide stainings. Analyses of the expression of cyclic cGMP, eNOS and iNOS were performed by means of RT-PCR and Western Blot. Results were analyzed using unpaired Students T-test. Analysis of endothelial cell apoptosis by MB indicated a dose-dependent increase of apoptotic cells. We observed time- and dose-dependent effects of MB on transendothelial migration of PBMCs. The prophylactic administration of MB led to an increase of transendothelial migration of PBMCs but not Jurkat cells. Furthermore, HuMEC-1 secretion of cGMP correlated with iNOS expression after MB administration but not with eNOS expression. Expression of these molecules was reduced after MB administration at protein level. This study clearly reveals that endothelial response to MB is dose- and especially time-dependent. MB shows different effects on circulating blood cell-subtypes, and modifies the release patterns of eNOS, iNOS, and cGMP. The transendothelial migration is modulated after treatment with MB. Furthermore, MB provokes apoptosis of endothelial cells in a dose

  6. Surface Modification of Intact Poly(dimethylsiloxane) for Cell Culture and Cell Migration

    Institute of Scientific and Technical Information of China (English)

    LI Li; LIU WenMing; WANG JinYi

    2009-01-01

    @@ Cell migration plays a crucial role in various biological processes including embryogenests,wound healing,immune response,and tissue development~([1]).Exploring and understanding the mechanisms and related factors underlying cell migration arc also very important for emerging areas of biotedmology which focus on cellular transplantation and the manufacture of artificial tissues,as well as for the development of new therapeutic strategies for controlling invasive tumor cells~([2]).

  7. BMP2 rescues deficient cell migration in Tgfbr3(-/-) epicardial cells and requires Src kinase.

    Science.gov (United States)

    Allison, Patrick; Espiritu, Daniella; Camenisch, Todd D

    2016-05-03

    During embryogenesis, the epicardium undergoes proliferation, migration, and differentiation into several cardiac cell types which contribute to the coronary vessels. The type III transforming growth factor-β receptor (TGFβR3) is required for epicardial cell invasion and development of coronary vasculature in vivo. Bone Morphogenic Protein-2 (BMP2) is a driver of epicardial cell migration. Utilizing a primary epicardial cell line derived from Tgfbr3(+/+) and Tgfbr3(-/-) mouse embryos, we show that Tgfbr3(-/-) epicardial cells are deficient in BMP2 mRNA expression. Tgfbr3(-/-) epicardial cells are deficient in 2-dimensional migration relative to Tgfbr3(+/+) cells; BMP2 induces cellular migration to Tgfbr3(+/+) levels without affecting proliferation. We further demonstrate that Src kinase activity is required for BMP2 driven Tgfbr3(-/-) migration. BMP2 also requires Src for filamentous actin polymerization in Tgfbr3(-/-) epicardial cells. Taken together, our data identifies a novel pathway in epicardial cell migration required for development of the coronary vessels.

  8. Leader cells define directionality of trunk, but not cranial, neural crest migration

    OpenAIRE

    Richardson, Jo; Gauert, Anton; Montecinos, Luis Briones; Fanlo, Lucía; Alhashem, Zainalabdeen Mohmammed; Assar, Rodrigo; MARTI, ELISA; Kabla, Alexandre; Härtel, Steffen; Linker, Claudia

    2016-01-01

    Summary:Collective cell migration is fundamental for life and a hallmark of cancer. Neural crest (NC) cells migrate collectively, but the mechanisms governing this process remain controversial. Previous analyses in Xenopus indicate that cranial NC (CNC) cells are a homogeneous population relying on cell-cell interactions for directional migration, while chick embryo analyses suggest a heterogeneous population with leader cells instructing directionality. Our data in chick and zebrafish embryo...

  9. Involvement of regulatory volume decrease in the migration of nasopharyngeal carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Jian Wen MAO; Li Xin CHEN; Li Wei WANG; Tim JACOB; Xue Rong SUN; Hui LI; Lin Yan ZHU; Pan LI; Ping ZHONG; Si Huai NIE

    2005-01-01

    The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5'-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of nonmigrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells.

  10. Fucan effect on CHO cell proliferation and migration

    OpenAIRE

    Nobre, Leonardo Thiago Duarte Barreto; Vidal, Arthur Anthunes Jacome; Almeida-Lima, Jailma; Oliveira, Ruth Medeiros; Paredes-Gamero, Edgar Jean [UNIFESP; Medeiros, Valquiria Pereira de [UNIFESP; Trindade, Edvaldo da Silva [UNIFESP; Franco,Celia Regina Cavichiolo; Nader, Helena Bonciani; Rocha, Hugo Alexandre Oliveira

    2013-01-01

    Fucan is a term used to denominate sulfated L-fucose rich polysaccharides. Here, a heterofucan, named fucan B, was extracted from the Spatoglossum schroederi seaweed. This 21.5 kDa galactofucan inhibited CHO-Kl proliferation and migration when fibronectin was the substrate. Fucan B derivatives revealed that such effects depend on their degree of sulfation. Fucan B did not induce cell death, but promoted G1 cell cycle arrest. Western blotting and flow cytometry analysis suggest that fucan B bi...

  11. Functional screening with a live cell imaging-based random cell migration assay.

    Science.gov (United States)

    van Roosmalen, Wies; Le Dévédec, Sylvia E; Zovko, Sandra; de Bont, Hans; van de Water, Bob

    2011-01-01

    Cell migration, essential in cancer progression, is a complex process comprising a number of spatiotemporally regulated and well-coordinated mechanisms. In order to study (random) cell migration in the context of responses to various external cues (such as growth factors) or intrinsic cell signaling, a number of different tools and approaches have been developed. In order to unravel the key pathways and players involved in the regulation of (cancer) cell migration, a systematical mapping of the players/pathways is required. For this purpose, we developed a cell migration assay based on automatic high-throughput microscopy screen. This approach allows for screening of hundreds of genes, e.g., those encoding various kinases and phosphatases but can also be used for screening of drugs libraries. Moreover, we have developed an automatic analysis pipeline comprising of (a) automatic data acquisition (movie) and (b) automatic analysis of the acquired movies of the migrating cells. Here, we describe various facets of this approach. Since cell migration is essential in progression of cancer metastasis, we describe two examples of experiments performed on highly motile (metastatic) cancer cells.

  12. Human Mesenchymal Stem Cell Morphology and Migration on Microtextured Titanium

    Science.gov (United States)

    Banik, Brittany L.; Riley, Thomas R.; Platt, Christina J.; Brown, Justin L.

    2016-01-01

    The implant used in spinal fusion procedures is an essential component to achieving successful arthrodesis. At the cellular level, the implant impacts healing and fusion through a series of steps: first, mesenchymal stem cells (MSCs) need to adhere and proliferate to cover the implant; second, the MSCs must differentiate into osteoblasts; third, the osteoid matrix produced by the osteoblasts needs to generate new bone tissue, thoroughly integrating the implant with the vertebrate above and below. Previous research has demonstrated that microtextured titanium is advantageous over smooth titanium and PEEK implants for both promoting osteogenic differentiation and integrating with host bone tissue; however, no investigation to date has examined the early morphology and migration of MSCs on these surfaces. This study details cell spreading and morphology changes over 24 h, rate and directionality of migration 6–18 h post-seeding, differentiation markers at 10 days, and the long-term morphology of MSCs at 7 days, on microtextured, acid-etched titanium (endoskeleton), smooth titanium, and smooth PEEK surfaces. The results demonstrate that in all metrics, the two titanium surfaces outperformed the PEEK surface. Furthermore, the rough acid-etched titanium surface presented the most favorable overall results, demonstrating the random migration needed to efficiently cover a surface in addition to morphologies consistent with osteoblasts and preosteoblasts. PMID:27243001

  13. Impaired energy metabolism of senescent muscle satellite cells is associated with oxidative modifications of glycolytic enzymes

    DEFF Research Database (Denmark)

    Baraibar, Martín A; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina

    2016-01-01

    Accumulation of oxidized proteins is a hallmark of cellular and organismal aging. Adult muscle stem cell (or satellite cell) replication and differentiation is compromised with age contributing to sarcopenia. However, the molecular events related to satellite cell dysfunction during aging...

  14. Satellite glial cells in sensory ganglia: its role in pain

    Directory of Open Access Journals (Sweden)

    Filipa Alexandra Leite Costa

    2015-02-01

    Full Text Available BACKGROUND AND OBJECTIVES: Satellite glial cells in sensory ganglia are a recent subject of research in the field of pain and a possible therapeutic target in the future. Therefore, the aim of this study was to summarize some of the important physiological and morphological characteristics of these cells and gather the most relevant scientific evidence about its possible role in the development of chronic pain. CONTENT: In the sensory ganglia, each neuronal body is surrounded by satellite glial cells forming distinct functional units. This close relationship enables bidirectional communication via a paracrine signaling between those two cell types. There is a growing body of evidence that glial satellite cells undergo structural and biochemical changes after nerve injury, which influence neuronal excitability and consequently the development and/or maintenance of pain in different animal models of chronic pain. CONCLUSIONS: Satellite glial cells are important in the establishment of physiological pain, in addition to being a potential target for the development of new pain treatments.

  15. Collective cell migration of thyroid carcinoma cells: a beneficial ability to override unfavourable substrates.

    Science.gov (United States)

    Lobastova, Liudmila; Kraus, Dominik; Glassmann, Alexander; Khan, Dilaware; Steinhäuser, Christian; Wolff, Christina; Veit, Nadine; Winter, Jochen; Probstmeier, Rainer

    2017-02-01

    Tumor cell invasion and metastasis are life threatening events. Invasive tumor cells tend to migrate as collective sheets. In the present in vitro study we aimed to (i) assess whether collective tumor cells gain benefits in their migratory potential compared to single cells and (ii) to identify its putative underlying molecular mechanisms. The migratory potential of single and collective carcinoma cells was assessed using video time lapse microscopy and cell migration assays in the absence and presence of seven potential gap junction inhibitors or the Rac1 inhibitor Z62954982. The perturbation of gap junctions was assessed using a dye diffusion assay. In addition, LDH-based cytotoxicity and RT-PCR-based expression analyses were performed. Whereas single breast, cervix and thyroid carcinoma cells were virtually immobile on unfavourable plastic surfaces, we found that they gained pronounced migratory capacities as collectives under comparable conditions. Thyroid carcinoma cells, that were studied in more detail, were found to express specific subsets of connexins and to form active gap junctions as revealed by dye diffusion analysis. Although all potential gap junction blockers suppressed intercellular dye diffusion in at least one of the cell lines tested, only two of them were found to inhibit collective cell migration and none of them to inhibit single cell migration. In the presence of the Rac1 inhibitor Z62954982 collective migration, but not single cell migration, was found to be reduced up to 20 %. Our data indicate that collective migration enables tumor cells to cross otherwise unfavourable substrate areas. This capacity seems to be independent of intercellular communication via gap junctions, whereas Rac1-dependent intracellular signalling seems to be essential.

  16. Intracellular pH gradients in migrating cells

    DEFF Research Database (Denmark)

    Martin, Christine; Pedersen, Stine Helene Falsig; Schwab, Albrecht

    2011-01-01

    might function as such unevenly distributed regulators as they modulate the interaction of focal adhesion proteins and components of the cytoskeleton in vitro. However, an intracellular pH (pH(i)) gradient reflecting a spatial asymmetry of protons has not been shown so far. One major regulator of pH......(i), the Na(+)/H(+) exchanger NHE1, is essential for cell migration and accumulates at the cell front. Here, we test the hypothesis that the uneven distribution of NHE1 activity creates a pH(i) gradient in migrating cells. Using the pH-sensitive fluorescent dye BCECF, pH(i) was measured in five cell lines (MV......3, B16V, NIH3T3, MDCK-F1, EA.hy926) along the axis of movement. Differences in pH(i) between the front and the rear end (¿pH(i) front-rear) were present in all cell lines, and inhibition of NHE1 either with HOE642 or by absence of extracellular Na(+) caused the pH(i) gradient to flatten or disappear...

  17. A large-scale (19) F MRI-based cell migration assay to optimize cell therapy.

    NARCIS (Netherlands)

    Bonetto, F.J.; Srinivas, M.; Weigelin, B.; Cruz, L.J.; Heerschap, A.; Friedl, P.H.A.; Figdor, C.G.; Vries, I.J.M. de

    2012-01-01

    Adoptive transfer of cells for therapeutic purposes requires efficient and precise delivery to the target organ whilst preserving cell function. Therefore, therapeutically applied cells need to migrate and integrate within their target tissues after delivery, e.g. dendritic cells (DCs) need to migra

  18. Mechanobiology of cell migration in the context of dynamic two-way cell-matrix interactions.

    Science.gov (United States)

    Kurniawan, Nicholas A; Chaudhuri, Parthiv Kant; Lim, Chwee Teck

    2016-05-24

    Migration of cells is integral in various physiological processes in all facets of life. These range from embryonic development, morphogenesis, and wound healing, to disease pathology such as cancer metastasis. While cell migratory behavior has been traditionally studied using simple assays on culture dishes, in recent years it has been increasingly realized that the physical, mechanical, and chemical aspects of the matrix are key determinants of the migration mechanism. In this paper, we will describe the mechanobiological changes that accompany the dynamic cell-matrix interactions during cell migration. Furthermore, we will review what is to date known about how these changes feed back to the dynamics and biomechanical properties of the cell and the matrix. Elucidating the role of these intimate cell-matrix interactions will provide not only a better multi-scale understanding of cell motility in its physiological context, but also a more holistic perspective for designing approaches to regulate cell behavior.

  19. Impact of tumor cell cytoskeleton organization on invasiveness and migration: a microchannel-based approach.

    Directory of Open Access Journals (Sweden)

    Claudio G Rolli

    Full Text Available Cell migration is a fundamental feature of the interaction of cells with their surrounding. The cell's stiffness and ability to deform itself are two major characteristics that rule migration behavior especially in three-dimensional tissue. We simulate this situation making use of a micro-fabricated migration chip to test the active invasive behavior of pancreatic cancer cells (Panc-1 into narrow channels. At a channel width of 7 microm cell migration through the channels was significantly impeded due to size exclusion. A striking increase in cell invasiveness was observed once the cells were treated with the bioactive lipid sphingosylphosphorylcholine (SPC that leads to a reorganization of the cell's keratin network, an enhancement of the cell's deformability, and also an increase in the cell's migration speed on flat surfaces. The migration speed of the highly deformed cells inside the channels was three times higher than of cells on flat substrates but was not affected upon SPC treatment. Cells inside the channels migrated predominantly by smooth sliding while maintaining constant cell length. In contrast, cells on adhesion mediating narrow lines moved in a stepwise way, characterized by fluctuations in cell length. Taken together, with our migration chip we demonstrate that the dimensionality of the environment strongly affects the migration phenotype and we suggest that the spatial cytoskeletal keratin organization correlates with the tumor cell's invasive potential.

  20. Satellite cell depletion prevents fiber hypertrophy in skeletal muscle.

    Science.gov (United States)

    Egner, Ingrid M; Bruusgaard, Jo C; Gundersen, Kristian

    2016-08-15

    The largest mammalian cells are the muscle fibers, and they have multiple nuclei to support their large cytoplasmic volumes. During hypertrophic growth, new myonuclei are recruited from satellite stem cells into the fiber syncytia, but it was recently suggested that such recruitment is not obligatory: overload hypertrophy after synergist ablation of the plantaris muscle appeared normal in transgenic mice in which most of the satellite cells were abolished. When we essentially repeated these experiments analyzing the muscles by immunohistochemistry and in vivo and ex vivo imaging, we found that overload hypertrophy was prevented in the satellite cell-deficient mice, in both the plantaris and the extensor digitorum longus muscles. We attribute the previous findings to a reliance on muscle mass as a proxy for fiber hypertrophy, and to the inclusion of a significant number of regenerating fibers in the analysis. We discuss that there is currently no model in which functional, sustainable hypertrophy has been unequivocally demonstrated in the absence of satellite cells; an exception is re-growth, which can occur using previously recruited myonuclei without addition of new myonuclei. © 2016. Published by The Company of Biologists Ltd.

  1. Cell Image Velocimetry (CIV): boosting the automated quantification of cell migration in wound healing assays.

    Science.gov (United States)

    Milde, Florian; Franco, Davide; Ferrari, Aldo; Kurtcuoglu, Vartan; Poulikakos, Dimos; Koumoutsakos, Petros

    2012-11-01

    Cell migration is commonly quantified by tracking the speed of the cell layer interface in wound healing assays. This quantification is often hampered by low signal to noise ratio, in particular when complex substrates are employed to emulate in vivo cell migration in geometrically complex environments. Moreover, information about the cell motion, readily available inside the migrating cell layers, is not usually harvested. We introduce Cell Image Velocimetry (CIV), a combination of cell layer segmentation and image velocimetry algorithms, to drastically enhance the quantification of cell migration by wound healing assays. The resulting software analyses the speed of the interface as well as the detailed velocity field inside the cell layers in an automated fashion. CIV is shown to be highly robust for images with low signal to noise ratio, low contrast and frame shifting and it is portable across various experimental settings. The modular design and parametrization of CIV is not restricted to wound healing assays and allows for the exploration and quantification of flow phenomena in any optical microscopy dataset. Here, we demonstrate the capabilities of CIV in wound healing assays over topographically engineered surfaces and quantify the relative merits of differently aligned gratings on cell migration.

  2. Co-culture with Sertoli cells promotes proliferation and migration of umbilical cord mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fenxi, E-mail: fxzhang0824@gmail.com [Department of Anatomy, Sanquan College, Xinxiang Medical University, Henan 453003, People' s Republic of China (China); Hong, Yan; Liang, Wenmei [Department of Histology and Embryology, Guiyang Medical University, Guizhou 550004, People' s Republic of China (China); Ren, Tongming [Department of Anatomy, Sanquan College, Xinxiang Medical University, Henan 453003, People' s Republic of China (China); Jing, Suhua [ICU Center, The Third Hospital of Xinxiang Medical University, Henan 453003, People' s Republic of China (China); Lin, Juntang [Stem Cell Center, Xinxiang Medical University, Henan 453003, People' s Republic of China (China)

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer Co-culture of Sertoli cells (SCs) with human umbilical cord mesenchymal stem cells (UCMSCs). Black-Right-Pointing-Pointer Presence of SCs dramatically increased proliferation and migration of UCMSCs. Black-Right-Pointing-Pointer Presence of SCs stimulated expression of Mdm2, Akt, CDC2, Cyclin D, CXCR4, MAPKs. -- Abstract: Human umbilical cord mesenchymal stem cells (hUCMSCs) have been recently used in transplant therapy. The proliferation and migration of MSCs are the determinants of the efficiency of MSC transplant therapy. Sertoli cells are a kind of 'nurse' cells that support the development of sperm cells. Recent studies show that Sertoli cells promote proliferation of endothelial cells and neural stem cells in co-culture. We hypothesized that co-culture of UCMSCs with Sertoli cells may also promote proliferation and migration of UCMSCs. To examine this hypothesis, we isolated UCMSCs from human cords and Sertoli cells from mouse testes, and co-cultured them using a Transwell system. We found that UCMSCs exhibited strong proliferation ability and potential to differentiate to other cell lineages such as osteocytes and adipocytes. The presence of Sertoli cells in co-culture significantly enhanced the proliferation and migration potential of UCMSCs (P < 0.01). Moreover, these phenotypic changes were accompanied with upregulation of multiple genes involved in cell proliferation and migration including phospho-Akt, Mdm2, phospho-CDC2, Cyclin D1, Cyclin D3 as well as CXCR4, phospho-p44 MAPK and phospho-p38 MAPK. These findings indicate that Sertoli cells boost UCMSC proliferation and migration potential.

  3. Probing Leader Cells in Endothelial Collective Migration by Plasma Lithography Geometric Confinement

    Science.gov (United States)

    Yang, Yongliang; Jamilpour, Nima; Yao, Baoyin; Dean, Zachary S.; Riahi, Reza; Wong, Pak Kin

    2016-03-01

    When blood vessels are injured, leader cells emerge in the endothelium to heal the wound and restore the vasculature integrity. The characteristics of leader cells during endothelial collective migration under diverse physiological conditions, however, are poorly understood. Here we investigate the regulation and function of endothelial leader cells by plasma lithography geometric confinement generated. Endothelial leader cells display an aggressive phenotype, connect to follower cells via peripheral actin cables and discontinuous adherens junctions, and lead migrating clusters near the leading edge. Time-lapse microscopy, immunostaining, and particle image velocimetry reveal that the density of leader cells and the speed of migrating clusters are tightly regulated in a wide range of geometric patterns. By challenging the cells with converging, diverging and competing patterns, we show that the density of leader cells correlates with the size and coherence of the migrating clusters. Collectively, our data provide evidence that leader cells control endothelial collective migration by regualting the migrating clusters.

  4. Probing Leader Cells in Endothelial Collective Migration by Plasma Lithography Geometric Confinement.

    Science.gov (United States)

    Yang, Yongliang; Jamilpour, Nima; Yao, Baoyin; Dean, Zachary S; Riahi, Reza; Wong, Pak Kin

    2016-03-03

    When blood vessels are injured, leader cells emerge in the endothelium to heal the wound and restore the vasculature integrity. The characteristics of leader cells during endothelial collective migration under diverse physiological conditions, however, are poorly understood. Here we investigate the regulation and function of endothelial leader cells by plasma lithography geometric confinement generated. Endothelial leader cells display an aggressive phenotype, connect to follower cells via peripheral actin cables and discontinuous adherens junctions, and lead migrating clusters near the leading edge. Time-lapse microscopy, immunostaining, and particle image velocimetry reveal that the density of leader cells and the speed of migrating clusters are tightly regulated in a wide range of geometric patterns. By challenging the cells with converging, diverging and competing patterns, we show that the density of leader cells correlates with the size and coherence of the migrating clusters. Collectively, our data provide evidence that leader cells control endothelial collective migration by regualting the migrating clusters.

  5. To The Abercrombie Meeting and back again: a journey into the world of cell migration.

    Science.gov (United States)

    Makowska, Katarzyna Anna

    2013-01-01

    The 7th Abercrombie Meeting took place in Oxford this past summer. It was organized by The Royal Microscopical Society with the support of The British Society for Cell Biology. Michael Abercrombie was a pioneer in the field of investigating cell behavior using time-lapse microscopy. The meeting was focused on "multi-dimensional cell migration in development and disease" and it brought together many of the world's leading researchers in the area, providing an opportunity to discuss the very latest advances and possible future developments in the field. The meeting sessions included Invasive Migration, Invasive Adhesions in Migrating Cells, Signaling in Migration, Immune Cell Migration, Migrations during Morphogenesis and Migration and Disease. As with all Abercrombie meetings, the conference delegates were treated to a staggering array of live cell imaging, in vivo imaging and images generated by the latest developments in microscopy.

  6. An Experimental Biotelemetric Study Based on Satellite Tracking During Post-nesting Migrations of Green Turtles

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A biotelemetry experiment is conducted to study the migrant behavior of green turtles (Chelonia mydas) in South China Sea and acquire the physical environment data. The method in use is to track the post-nesting migrant routes of green turtles through the satellite linked transmitters attached on the back of turtles and the global satellite signal transmitting system of Argos. We obtained the posinestions of the post-nesting migrant routes of three green turtles and environment data, which are important in conservation of green turtles and the research of physical oceanography. Based on the test, the concept, principle and method of biotelemetry are also introduced in this paper with a discussion of the further development of this technique and its applying prospection in future.

  7. Lymph node topology dictates T cell migration behavior.

    Science.gov (United States)

    Beltman, Joost B; Marée, Athanasius F M; Lynch, Jennifer N; Miller, Mark J; de Boer, Rob J

    2007-04-16

    Adaptive immunity is initiated by T cell recognition of foreign peptides presented on dendritic cells (DCs) by major histocompatibility molecules. These interactions take place in secondary lymphoid tissues, such as lymph nodes (LNs) and spleen, and hence the anatomical structure of these tissues plays a crucial role in the development of immune responses. Two-photon microscopy (2PM) imaging in LNs suggests that T cells walk in a consistent direction for several minutes, pause briefly with a regular period, and then take off in a new, random direction. Here, we construct a spatially explicit model of T cell and DC migration in LNs and show that all dynamical properties of T cells could be a consequence of the densely packed LN environment. By means of 2PM experiments, we confirm that the large velocity fluctuations of T cells are indeed environmentally determined rather than resulting from an intrinsic motility program. Our simulations further predict that T cells self-organize into microscopically small, highly dynamic streams. We present experimental evidence for the presence of such turbulent streams in LNs. Finally, the model allows us to estimate the scanning rates of DCs (2,000 different T cells per hour) and T cells (100 different DCs per hour).

  8. Neonatal Satellite Cells Form Small Myotubes in Vitro

    NARCIS (Netherlands)

    Carvajal Monroy, P.L.; Grefte, S.; Kuijpers-Jagtman, A.M.; Den Hoff, Von J.W.; Wagener, F.A.D.T.G.

    2017-01-01

    Although palatal muscle reconstruction in patients with cleft palate takes place during early childhood, normal speech development is often not achieved. We hypothesized that the intrinsic properties of head satellite cells (SCs) and the young age of these patients contribute to the poor muscle

  9. Tre1, a G protein-coupled receptor, directs transepithelial migration of Drosophila germ cells.

    Directory of Open Access Journals (Sweden)

    Prabhat S Kunwar

    2003-12-01

    Full Text Available In most organisms, germ cells are formed distant from the somatic part of the gonad and thus have to migrate along and through a variety of tissues to reach the gonad. Transepithelial migration through the posterior midgut (PMG is the first active step during Drosophila germ cell migration. Here we report the identification of a novel G protein-coupled receptor (GPCR, Tre1, that is essential for this migration step. Maternal tre1 RNA is localized to germ cells, and tre1 is required cell autonomously in germ cells. In tre1 mutant embryos, most germ cells do not exit the PMG. The few germ cells that do leave the midgut early migrate normally to the gonad, suggesting that this gene is specifically required for transepithelial migration and that mutant germ cells are still able to recognize other guidance cues. Additionally, inhibiting small Rho GTPases in germ cells affects transepithelial migration, suggesting that Tre1 signals through Rho1. We propose that Tre1 acts in a manner similar to chemokine receptors required during transepithelial migration of leukocytes, implying an evolutionarily conserved mechanism of transepithelial migration. Recently, the chemokine receptor CXCR4 was shown to direct migration in vertebrate germ cells. Thus, germ cells may more generally use GPCR signaling to navigate the embryo toward their target.

  10. Epac1 increases migration of endothelial cells and melanoma cells via FGF2-mediated paracrine signaling

    DEFF Research Database (Denmark)

    Baljinnyam, Erdene; Umemura, Masanari; Chuang, Christine

    2014-01-01

    Fibroblast growth factor (FGF2) regulates endothelial and melanoma cell migration. The binding of FGF2 to its receptor requires N-sulfated heparan sulfate (HS) glycosamine. We have previously reported that Epac1, an exchange protein activated by cAMP, increases N-sulfation of HS in melanoma....... Therefore, we examined whether Epac1 regulates FGF2-mediated cell-cell communication. Conditioned medium (CM) of melanoma cells with abundant expression of Epac1 increased migration of human umbilical endothelial cells (HUVEC) and melanoma cells with poor expression of Epac1. CM-induced increase...... in migration was inhibited by antagonizing FGF2, by the removal of HS and by the knockdown of Epac1. In addition, knockdown of Epac1 suppressed the binding of FGF2 to FGF receptor in HUVEC, and in vivo angiogenesis in melanoma. Furthermore, knockdown of Epac1 reduced N-sulfation of HS chains attached...

  11. Interplay of RhoA and mechanical forces in collective cell migration driven by leader cells.

    Science.gov (United States)

    Reffay, M; Parrini, M C; Cochet-Escartin, O; Ladoux, B; Buguin, A; Coscoy, S; Amblard, F; Camonis, J; Silberzan, P

    2014-03-01

    The leading front of a collectively migrating epithelium often destabilizes into multicellular migration fingers where a cell initially similar to the others becomes a leader cell while its neighbours do not alter. The determinants of these leader cells include mechanical and biochemical cues, often under the control of small GTPases. However, an accurate dynamic cartography of both mechanical and biochemical activities remains to be established. Here, by mapping the mechanical traction forces exerted on the surface by MDCK migration fingers, we show that these structures are mechanical global entities with the leader cells exerting a large traction force. Moreover, the spatial distribution of RhoA differential activity at the basal plane strikingly mirrors this force cartography. We propose that RhoA controls the development of these fingers through mechanical cues: the leader cell drags the structure and the peripheral pluricellular acto-myosin cable prevents the initiation of new leader cells.

  12. Primary mesenchyme cell migration requires a chondroitin sulfate/dermatan sulfate proteoglycan.

    Science.gov (United States)

    Lane, M C; Solursh, M

    1991-02-01

    Primary mesenchyme cell migration in the sea urchin embryo is inhibited by sulfate deprivation and exposure to exogenous beta-D-xylosides, two treatments known to disrupt proteoglycan synthesis. We show that in the developing sea urchin, exogenous xyloside affects the synthesis by the primary mesenchyme cells of a very large, cell surface chondroitin sulfate/dermatan sulfate proteoglycan. This proteoglycan is present in a partially purified fraction that restores migratory ability to defective cells in vitro. The integrity of this chondroitin sulfate/dermatan sulfate proteoglycan appears essential for primary mesenchyme cell migration since treatment of actively migrating cells with chondroitinase ABC reversibly inhibited their migration in vitro.

  13. RNase L Suppresses Androgen Receptor Signaling, Cell Migration and Matrix Metalloproteinase Activity in Prostate Cancer Cells

    Science.gov (United States)

    Dayal, Shubham; Zhou, Jun; Manivannan, Praveen; Siddiqui, Mohammad Adnan; Ahmad, Omaima Farid; Clark, Matthew; Awadia, Sahezeel; Garcia-Mata, Rafael; Shemshedini, Lirim; Malathi, Krishnamurthy

    2017-01-01

    The interferon antiviral pathways and prostate cancer genetics converge on a regulated endoribonuclease, RNase L. Positional cloning and linkage studies mapped Hereditary Prostate Cancer 1 (HPC1) to RNASEL. To date, there is no correlation of viral infections with prostate cancer, suggesting that RNase L may play additional roles in tumor suppression. Here, we demonstrate a role of RNase L as a suppressor of androgen receptor (AR) signaling, cell migration and matrix metalloproteinase activity. Using RNase L mutants, we show that its nucleolytic activity is dispensable for both AR signaling and migration. The most prevalent HPC1-associated mutations in RNase L, R462Q and E265X, enhance AR signaling and cell migration. RNase L negatively regulates cell migration and attachment on various extracellular matrices. We demonstrate that RNase L knockdown cells promote increased cell surface expression of integrin β1 which activates Focal Adhesion Kinase-Sarcoma (FAK-Src) pathway and Ras-related C3 botulinum toxin substrate 1-guanosine triphosphatase (Rac1-GTPase) activity to increase cell migration. Activity of matrix metalloproteinase (MMP)-2 and -9 is significantly increased in cells where RNase L levels are ablated. We show that mutations in RNase L found in HPC patients may promote prostate cancer by increasing expression of AR-responsive genes and cell motility and identify novel roles of RNase L as a prostate cancer susceptibility gene. PMID:28257035

  14. RNase L Suppresses Androgen Receptor Signaling, Cell Migration and Matrix Metalloproteinase Activity in Prostate Cancer Cells.

    Science.gov (United States)

    Dayal, Shubham; Zhou, Jun; Manivannan, Praveen; Siddiqui, Mohammad Adnan; Ahmad, Omaima Farid; Clark, Matthew; Awadia, Sahezeel; Garcia-Mata, Rafael; Shemshedini, Lirim; Malathi, Krishnamurthy

    2017-03-01

    The interferon antiviral pathways and prostate cancer genetics converge on a regulated endoribonuclease, RNase L. Positional cloning and linkage studies mapped Hereditary Prostate Cancer 1 (HPC1) to RNASEL. To date, there is no correlation of viral infections with prostate cancer, suggesting that RNase L may play additional roles in tumor suppression. Here, we demonstrate a role of RNase L as a suppressor of androgen receptor (AR) signaling, cell migration and matrix metalloproteinase activity. Using RNase L mutants, we show that its nucleolytic activity is dispensable for both AR signaling and migration. The most prevalent HPC1-associated mutations in RNase L, R462Q and E265X, enhance AR signaling and cell migration. RNase L negatively regulates cell migration and attachment on various extracellular matrices. We demonstrate that RNase L knockdown cells promote increased cell surface expression of integrin β1 which activates Focal Adhesion Kinase-Sarcoma (FAK-Src) pathway and Ras-related C3 botulinum toxin substrate 1-guanosine triphosphatase (Rac1-GTPase) activity to increase cell migration. Activity of matrix metalloproteinase (MMP)-2 and -9 is significantly increased in cells where RNase L levels are ablated. We show that mutations in RNase L found in HPC patients may promote prostate cancer by increasing expression of AR-responsive genes and cell motility and identify novel roles of RNase L as a prostate cancer susceptibility gene.

  15. RNase L Suppresses Androgen Receptor Signaling, Cell Migration and Matrix Metalloproteinase Activity in Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Shubham Dayal

    2017-03-01

    Full Text Available The interferon antiviral pathways and prostate cancer genetics converge on a regulated endoribonuclease, RNase L. Positional cloning and linkage studies mapped Hereditary Prostate Cancer 1 (HPC1 to RNASEL. To date, there is no correlation of viral infections with prostate cancer, suggesting that RNase L may play additional roles in tumor suppression. Here, we demonstrate a role of RNase L as a suppressor of androgen receptor (AR signaling, cell migration and matrix metalloproteinase activity. Using RNase L mutants, we show that its nucleolytic activity is dispensable for both AR signaling and migration. The most prevalent HPC1-associated mutations in RNase L, R462Q and E265X, enhance AR signaling and cell migration. RNase L negatively regulates cell migration and attachment on various extracellular matrices. We demonstrate that RNase L knockdown cells promote increased cell surface expression of integrin β1 which activates Focal Adhesion Kinase-Sarcoma (FAK-Src pathway and Ras-related C3 botulinum toxin substrate 1-guanosine triphosphatase (Rac1-GTPase activity to increase cell migration. Activity of matrix metalloproteinase (MMP-2 and -9 is significantly increased in cells where RNase L levels are ablated. We show that mutations in RNase L found in HPC patients may promote prostate cancer by increasing expression of AR-responsive genes and cell motility and identify novel roles of RNase L as a prostate cancer susceptibility gene.

  16. Arecoline inhibits endothelial cell growth and migration and the attachment to mononuclear cells

    Directory of Open Access Journals (Sweden)

    Shuei-Kuen Tseng

    2014-09-01

    Conclusion: Arecoline impaired vascular endothelial cells by inhibiting their growth and migration and their adhesion to U937 mononuclear cells. These results reveal that arecoline may contribute to the pathogenesis of oral submucous fibrosis and cardiovascular diseases by affecting endothelial cell function in BQ chewers.

  17. Notch1-Dll4 signalling and mechanical force regulate leader cell formation during collective cell migration.

    Science.gov (United States)

    Riahi, Reza; Sun, Jian; Wang, Shue; Long, Min; Zhang, Donna D; Wong, Pak Kin

    2015-03-13

    At the onset of collective cell migration, a subset of cells within an initially homogenous population acquires a distinct 'leader' phenotype with characteristic morphology and motility. However, the factors driving the leader cell formation as well as the mechanisms regulating leader cell density during the migration process remain to be determined. Here we use single-cell gene expression analysis and computational modelling to show that the leader cell identity is dynamically regulated by Dll4 signalling through both Notch1 and cellular stress in a migrating epithelium. Time-lapse microscopy reveals that Dll4 is induced in leader cells after the creation of the cell-free region and leader cells are regulated via Notch1-Dll4 lateral inhibition. Furthermore, mechanical stress inhibits Dll4 expression and leader cell formation in the monolayer. Collectively, our findings suggest that a reduction of mechanical force near the boundary promotes Notch1-Dll4 signalling to dynamically regulate the density of leader cells during collective cell migration.

  18. Impaired migration and cell volume regulation in aquaporin 5-deficient SPC-A1 cells.

    Science.gov (United States)

    Chen, Zhihong; Zhang, Ziqiang; Gu, Yutong; Bai, Chunxue

    2011-05-31

    Aquaporin 5 (AQP5) is widely expressed in various organ and tissues. In light of the novel oncogenic properties of aquaporins (AQPs), here we investigated the effect of AQP5 knockdown by RNAi on transmembrane osmotic water permeability, cell migration potential and cell volume regulation ability. AQP5 expression was inhibited by short hairpin RNA in SPC-A1 cells, a lung adenocarcinoma cell line. Cells loaded with a fluoroprobe (calcein-AM) were immersed in either isosmotic, hyperosmotic or hyposmotic solutions, and fluorescence intensity was recorded using confocal microscopy. These measurements were used to calculate osmotic water permeability coefficients (Pf) and to monitor regulated volume decrease (RVD). Tumor cell migration and invasion assays were performed in a modified Boyden chamber. Wound healing and colony forming ability were also tested. Although self-quenching was not found in SPC-A1 cells, we observed a linear relationship between fluorescence intensity and cell water volume, suggesting that this method is a sensitive and reproducible way to measure single-cell transmembrane water permeability. Cells in which the AQP5 gene was silenced showed a 49.4% decrease in osmotic water permeability, a 55.3% decrease in migration and a 28.4% decrease in invasion potential. In addition, RVD decreased remarkably with reduced osmotic water permeability. Our results suggest that AQP5, which mediates water permeability and thus regulates cell shape and volume, is a potentially important determinant in cell migration. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Multi-Walled Carbon Nanotubes Inhibit Breast Cancer Cell Migration.

    Science.gov (United States)

    Graham, Elizabeth G; Wailes, Elizabeth M; Levi-Polyachenko, Nicole H

    2016-02-01

    According to the American Cancer Society, breast cancer is the second leading cause of cancer death in the US. Cancerous cells may have inadequate adhesions to the extracellular matrix and adjacent cells. Previous work has suggested that restoring these contacts may negate the cancer phenotype. This work aims to restore those contacts using multi-walled carbon nanotubes (MWNTs). Varying concentrations of carboxylated MWNTs in water, with or without type I collagen, were dried to create a thin film upon which one of three breast cell lines were seeded: cancerous and metastatic MDA- MB-231 cells, cancerous but non-metastatic MCF7 cells, or non-cancerous MCF10A cells. Proliferation, adhesion, scratch and autophagy assays, western blots, and immunochemical staining were used to assess adhesion and E-cadherin expression. Breast cancer cells grown on a MWNT-collagen coated surface displayed increased adhesion and decreased migration which correlated with an increase in E-cadherin. This work suggests an alternative approach to cancer treatment by physically mediating the cells' microenvironment.

  20. Analysis of CCR7 mediated T cell transfectant migration using a microfluidic gradient generator.

    Science.gov (United States)

    Wu, Xun; Wu, Jiandong; Li, Hongzhao; Legler, Daniel F; Marshall, Aaron J; Lin, Francis

    2015-04-01

    T lymphocyte migration is crucial for adaptive immunity. Manipulation of signaling molecules controlling cell migration combined with in-vitro cell migration analysis provides a powerful research approach. Microfluidic devices, which can precisely configure chemoattractant gradients and allow quantitative single cell analysis, have been increasingly applied to cell migration and chemotaxis studies. However, there are a very limited number of published studies involving microfluidic migration analysis of genetically manipulated immune cells. In this study, we describe a simple microfluidic method for quantitative analysis of T cells expressing transfected chemokine receptors and other cell migration signaling probes. Using this method, we demonstrated chemotaxis of Jurkat transfectants expressing wild-type or C-terminus mutated CCR7 within a gradient of chemokine CCL19, and characterized the difference in transfectant migration mediated by wild-type and mutant CCR7. The EGFP-tagged CCR7 allows identification of CCR7-expressing transfectants in cell migration analysis and microscopy assessment of CCR7 dynamics. Collectively, our study demonstrated the effective use of the microfluidic method for studying CCR7 mediated T cell transfectant migration. We envision this developed method will provide a useful platform to functionally test various signaling mechanisms at the cell migration level.

  1. Actin-Based Feedback Circuits in Cell Migration and Endocytosis

    Science.gov (United States)

    Wang, Xinxin

    In this thesis, we study the switch and pulse functions of actin during two important cellular processes, cell migration and endocytosis. Actin is an abundant protein that can polymerize to form a dendritic network. The actin network can exert force to push or bend the cell membrane. During cell migration, the actin network behaves like a switch, assembling mostly at one end or at the other end. The end with the majority of the actin network is the leading edge, following which the cell can persistently move in the same direction. The other end, with the minority of the actin network, is the trailing edge, which is dragged by the cell as it moves forward. When subjected to large fluctuations or external stimuli, the leading edge and the trailing edge can interchange and change the direction of motion, like a motion switch. Our model of the actin network in a cell reveals that mechanical force is crucial for forming the motion switch. We find a transition from single state symmetric behavior to switch behavior, when tuning parameters such as the force. The model is studied by both stochastic simulations, and a set of rate equations that are consistent with the simulations. Endocytosis is a process by which cells engulf extracellular substances and recycle the cell membrane. In yeast cells, the actin network is transiently needed to overcome the pressure difference across the cell membrane caused by turgor pressure. The actin network behaves like a pulse, which assembles and then disassembles within about 30 seconds. Using a stochastic model, we reproduce the pulse behaviors of the actin network and one of its regulatory proteins, Las17. The model matches green fluorescence protein (GFP) experiments for wild-type cells. The model also predicts some phenotypes that modify or diminish the pulse behavior. The phenotypes are verified with both experiments performed at Washington University and with other groups' experiments. We find that several feedback mechanisms are

  2. Cell growth and migration under octenidine-antiseptic treatment.

    Science.gov (United States)

    Jenull, S; Hojdar, K; Laggner, H; Velimirov, B; Zemann, N; Huettinger, M

    2015-06-01

    The toxicity of octenidine antiseptics in cultured cells contrasts their good tolerability in tissue. This phenomenon prompted us to examine which cell culture conditions allow survival and proliferation and to investigate a possible modulation of toxicity by the extracellular matrix proteoglycan chondroitin sulfate. We tested fibroblasts and MCF7 cells for growth using the MTT test, and assessed wound healing potency with a laceration assay. Expression levels of the genes involved in controlling wound healing were assessed with RT-PCR. A 24 hour exposure to the octenidine-based solution was found incompatible with cell growth. When octenidine solution (0.5-0.5mg/l) was coated on dishes, growth was profoundly reduced after 24 hours, however there was no cytotoxic effect at 0.012 mg/l. Interestingly, when dishes were first coated with chondroitin sulfate the cytotoxicity of octenidine-based solution was modulated. Cell migration was not inhibited by octenidine-based solution treatment (2 minutes; 15 mg/l). No significant changes in gene expression levels in response to the octenidine-based solution treatment were detected. In cell culture conditions application of the octenidine-based solution without toxicity can be observed, comparable to the minimal application required to give full bactericidal effect. Alteration of toxicity by interaction with chondroitin sulfate in cell culture suggests a similar function for extraceullar matrix in intact tissue.

  3. Substrate elasticity affects bovine satellite cell activation kinetics in vitro.

    Science.gov (United States)

    Lapin, M R; Gonzalez, J M; Johnson, S E

    2013-05-01

    Satellite cells support efficient postnatal skeletal muscle hypertrophy through fusion into the adjacent muscle fiber. Nuclear contribution allows for maintenance of the fiber myonuclear domain and proficient transcription of myogenic genes. Niche growth factors affect satellite cell biology; however, the interplay between fiber elasticity and microenvironment proteins remains largely unknown. The objective of the experiment was to examine the effects of hepatocyte growth factor (HGF) and surface elasticity on bovine satellite cell (BSC) activation kinetics in vitro. Young's elastic modulus was calculated for the semimembranosus (SM) and LM muscles of young bulls (5 d; n = 8) and adult cows (27 mo; n = 4) cattle. Results indicate that LM elasticity decreased (P Young's modulus for the SM was noted. Bovine satellite cells were seeded atop polyacrylamide bioscaffolds with surface elasticities that mimic young bull and adult cow LM or traditional cultureware. Cells were maintained in low-serum media supplemented with 5 ng/mL HGF or vehicle only for 24 or 48 h. Activation was evaluated by proliferating cell nuclear antigen (PCNA) immunocytochemistry. Results indicate that BSC maintained on rigid surfaces were activated at 24 h and refractive to HGF supplementation. By contrast, fewer (P young bull (8.1 ± 1.7 kPa) or adult cow (14.6 ± 1.6 kPa) LM. Supplementation with HGF promoted activation of BSC cultured on bioscaffolds as measured by an increase (P muscle stem cells (P > 0.05). However, with increasing surface elasticity, an increase (P muscle progenitors was observed. These results confirm that biophysical and biochemical signals regulate BSC activation.

  4. Putting the brakes on cancer cell migration: JAM-A restrains integrin activation.

    Science.gov (United States)

    Naik, Ulhas P; Naik, Meghna U

    2008-01-01

    Junctional Adhesion Molecule A (JAM-A) is a member of the Ig superfamily of membrane proteins expressed in platelets, leukocytes, endothelial cells and epithelial cells. We have previously shown that in endothelial cells, JAM-A regulates basic fibroblast growth factor, (FGF-2)-induced angiogenesis via augmenting endothelial cell migration. Recently, we have revealed that in breast cancer cells, downregulation of JAM-A enhances cancer cell migration and invasion. Further, ectopic expression of JAM-A in highly metastatic MDA-MB-231 cells attenuates cell migration, and downregulation of JAM-A in low-metastatic T47D cells enhance migration. Interestingly, JAM-A expression is greatly diminished as breast cancer disease progresses. The molecular mechanism of this function of JAM-A is beyond its well-characterized barrier function at the tight junction. Our results point out that JAM-A differentially regulates migration of endothelial and cancer cells.

  5. Collective cell migration requires suppression of actomyosin at cell-cell contacts mediated by DDR1 and the cell polarity regulators Par3 and Par6

    OpenAIRE

    Hidalgo-Carcedo, Cristina; Hooper, Steven; Chaudhry, Shahid I.; Williamson, Peter; Harrington, Kevin; Leitinger, Birgit; Sahai, Erik

    2010-01-01

    Collective cell migration occurs in a range of contexts: cancer cells frequently invade in cohorts while retaining cell-cell junctions. Here we show that collective cancer cell invasion depends on reducing actomyosin contractility at sites of cell-cell contact. When actomyosin is not down-regulated at cell-cell contacts migrating cells lose cohesion. We provide a novel molecular mechanism for this down-regulation. Depletion of Discoidin Domain Receptor 1 (DDR1) blocks collective cancer cell i...

  6. Stromal Cell-Derived Factor-1 Promotes Cell Migration, Tumor Growth of Colorectal Metastasis

    Directory of Open Access Journals (Sweden)

    Otto Kollmar

    2007-10-01

    Full Text Available In a mouse model of established extrahepatic colorectal metastasis, we analyzed whether stromal cellderived factor (SDF 1 stimulates tumor cell migration in vitro, angiogenesis, tumor growth in vivo. METHODS: Using chemotaxis chambers, CT26.WT colorectal tumor cell migration was studied under stimulation with different concentrations of SDF-1. To evaluate angiogenesis, tumor growth in vivo, green fluorescent protein-transfected CT26.WT cells were implanted in dorsal skinfold chambers of syngeneic BALB/c mice. After 5 days, tumors were locally exposed to SDF-1. Cell proliferation, tumor microvascularization, growth were studied during a further 9-day period using intravital fluorescence microscopy, histology, immunohistochemistry. Tumors exposed to PBS only served as controls. RESULTS:In vitro, > 30% of unstimulated CT26.WT cells showed expression of the SDF-1 receptor CXCR4. On chemotaxis assay, SDF-1 provoked a dose-dependent increase in cell migration. In vivo, SDF-1 accelerated neovascularization, induced a significant increase in tumor growth. Capillaries of SDF-1-treated tumors showed significant dilation. Of interest, SDF-1 treatment was associated with a significantly increased expression of proliferating cell nuclear antigen, a downregulation of cleaved caspase-3. CONCLUSION: Our study indicates that the CXC chemokine SDF-1 promotes tumor cell migration in vitro, tumor growth of established extrahepatic metastasis in vivo due to angiogenesis-dependent induction of tumor cell proliferation, inhibition of apoptotic cell death.

  7. Selective migration of neuralized embryonic stem cells to stem cell factor and media conditioned by glioma cell lines

    Science.gov (United States)

    Serfozo, Peter; Schlarman, Maggie S; Pierret, Chris; Maria, Bernard L; Kirk, Mark D

    2006-01-01

    Background Pluripotent mouse embryonic stem (ES) cells can be induced in vitro to become neural progenitors. Upon transplantation, neural progenitors migrate toward areas of damage and inflammation in the CNS. We tested whether undifferentiated and neuralized mouse ES cells migrate toward media conditioned by glioma cell lines (C6, U87 & N1321) or Stem Cell Factor (SCF). Results Cell migration assays revealed selective migration by neuralized ES cells to conditioned media as well as to synthetic SCF. Migration of undifferentiated ES cells was extensive, but not significantly different from that of controls (Unconditioned Medium). RT-PCR analysis revealed that all the three tumor cell lines tested synthesized SCF and that both undifferentiated and neuralized ES cells expressed c-kit, the receptor for SCF. Conclusion Our results demonstrate that undifferentiated ES cells are highly mobile and that neural progenitors derived from ES cells are selectively attracted toward factors produced by gliomas. Given that the glioma cell lines synthesize SCF, SCF may be one of several factors that contribute to the selective migration observed. PMID:16436212

  8. Selective migration of neuralized embryonic stem cells to stem cell factor and media conditioned by glioma cell lines

    Directory of Open Access Journals (Sweden)

    Maria Bernard L

    2006-01-01

    Full Text Available Abstract Background Pluripotent mouse embryonic stem (ES cells can be induced in vitro to become neural progenitors. Upon transplantation, neural progenitors migrate toward areas of damage and inflammation in the CNS. We tested whether undifferentiated and neuralized mouse ES cells migrate toward media conditioned by glioma cell lines (C6, U87 & N1321 or Stem Cell Factor (SCF. Results Cell migration assays revealed selective migration by neuralized ES cells to conditioned media as well as to synthetic SCF. Migration of undifferentiated ES cells was extensive, but not significantly different from that of controls (Unconditioned Medium. RT-PCR analysis revealed that all the three tumor cell lines tested synthesized SCF and that both undifferentiated and neuralized ES cells expressed c-kit, the receptor for SCF. Conclusion Our results demonstrate that undifferentiated ES cells are highly mobile and that neural progenitors derived from ES cells are selectively attracted toward factors produced by gliomas. Given that the glioma cell lines synthesize SCF, SCF may be one of several factors that contribute to the selective migration observed.

  9. Iodine Migration and its Effect on Hysteresis in Perovskite Solar Cells.

    Science.gov (United States)

    Li, Cheng; Tscheuschner, Steffen; Paulus, Fabian; Hopkinson, Paul E; Kießling, Johannes; Köhler, Anna; Vaynzof, Yana; Huettner, Sven

    2016-03-23

    The migration and accumulation of iodide ions create a modulation of the respective interfacial barriers causing the hysteresis in solar cells based on methylammonium lead iodide perovskites. Iodide ions are identified as the migrating species by measuring temperature dependent current-transients and photoelectron spectroscopy. The involved changes in the built-in potential due to ion migration are directly measured by electroabsorption spectroscopy.

  10. Nuclear receptors Nur77 and Nurr1 modulate mesenchymal stromal cell migration

    NARCIS (Netherlands)

    Maijenburg, M.W.; Gilissen, C.; Melief, S.M.; Kleijer, M.; Weijer, K.; Ten Brinke, A.; Roelofs, H.; Tiel, C.M. van; Veltman, J.A.; Vries, C.J. de; Schoot, C.E. van der; Voermans, C.

    2012-01-01

    Detailed understanding of mesenchymal stromal cells (MSC) migration is imperative for future cellular therapies. To identify genes involved in the process of MSC migration, we generated gene expression profiles of migrating and nonmigrating fetal bone marrow MSC (FBMSC). Only 12 genes showed differe

  11. Heparan Sulfate Proteoglycans Regulate Fgf Signaling and Cell Polarity during Collective Cell Migration

    Directory of Open Access Journals (Sweden)

    Marina Venero Galanternik

    2015-01-01

    Full Text Available Collective cell migration is a highly regulated morphogenetic movement during embryonic development and cancer invasion that involves the precise orchestration and integration of cell-autonomous mechanisms and environmental signals. Coordinated lateral line primordium migration is controlled by the regulation of chemokine receptors via compartmentalized Wnt/β-catenin and fibroblast growth factor (Fgf signaling. Analysis of mutations in two exostosin glycosyltransferase genes (extl3 and ext2 revealed that loss of heparan sulfate (HS chains results in a failure of collective cell migration due to enhanced Fgf ligand diffusion and loss of Fgf signal transduction. Consequently, Wnt/β-catenin signaling is activated ectopically, resulting in the subsequent loss of the chemokine receptor cxcr7b. Disruption of HS proteoglycan (HSPG function induces extensive, random filopodia formation, demonstrating that HSPGs are involved in maintaining cell polarity in collectively migrating cells. The HSPGs themselves are regulated by the Wnt/β-catenin and Fgf pathways and thus are integral components of the regulatory network that coordinates collective cell migration with organ specification and morphogenesis.

  12. Inferring single-cell behaviour from large-scale epithelial sheet migration patterns.

    Science.gov (United States)

    Lee, Rachel M; Yue, Haicen; Rappel, Wouter-Jan; Losert, Wolfgang

    2017-05-01

    Cell migration plays an important role in a wide variety of biological processes and can incorporate both individual cell motion and collective behaviour. The emergent properties of collective migration are receiving increasing attention as collective motion's role in diseases such as metastatic cancer becomes clear. Yet, how individual cell behaviour influences large-scale, multi-cell collective motion remains unclear. In this study, we provide insight into the mechanisms behind collective migration by studying cell migration in a spreading monolayer of epithelial MCF10A cells. We quantify migration using particle image velocimetry and find that cell groups have features of motion that span multiple length scales. Comparing our experimental results to a model of collective cell migration, we find that cell migration within the monolayer can be affected in qualitatively different ways by cell motion at the boundary, yet it is not necessary to introduce leader cells at the boundary or specify other large-scale features to recapitulate this large-scale phenotype in simulations. Instead, in our model, collective motion can be enhanced by increasing the overall activity of the cells or by giving the cells a stronger coupling between their motion and polarity. This suggests that investigating the activity and polarity persistence of individual cells will add insight into the collective migration phenotypes observed during development and disease. © 2017 The Author(s).

  13. Cytoglobin inhibits migration through PI3K/AKT/mTOR pathway in fibroblast cells.

    Science.gov (United States)

    Demirci, Selami; Doğan, Ayşegül; Apdik, Hüseyin; Tuysuz, Emre Can; Gulluoglu, Sukru; Bayrak, Omer Faruk; Şahin, Fikrettin

    2017-06-15

    Cell proliferation and migration are crucial in many physiological processes including development, cancer, tissue repair, and wound healing. Cell migration is regulated by several signaling molecules. Identification of genes related to cell migration is required to understand molecular mechanism of non-healing chronic wounds which is a major concern in clinics. In the current study, the role of cytoglobin (CYGB) gene in fıbroblast cell migration and proliferation was described. L929 mouse fibroblast cells were transduced with lentiviral particles for CYGB and GFP, and analyzed for cell proliferation and migration ability. Fibroblast cells overexpressing CYGB displayed decreased cell proliferation, colony formation capacity, and cell migration. Phosphorylation levels of mTOR and two downstream effectors S6 and 4E-BP1 which take part in PI3K/AKT/mTOR signaling declined in CYGB-overexpressing cells. Microarray analysis indicated that CYGB overexpression leads to downregulation of cell proliferation, migration, and tumor growth associated genes in L929 cell line. This study demonstrated the role of CYGB in fibroblast cell motility and proliferation. CYGB could be a promising candidate for further studies as a potential target for diseases related to cell migration such as cancer and chronic wound treatment.

  14. Polydatin induces bone marrow stromal cells migration by activation of ERK1/2.

    Science.gov (United States)

    Chen, ZhenQiu; Wei, QiuShi; Hong, GuoJu; Chen, Da; Liang, Jiang; He, Wei; Chen, Mei Hui

    2016-08-01

    Bone marrow stromal cells (BMSCs) have proven to be useful for the treatment of numerous human diseases. However, the reparative ability of BMSCs is limited by their poor migration. Polydatin, widely used in traditional Chinese remedies, has proven to exert protective effects to BMSCs. However, little is known about its role in BMSCs migration. In this study, we studied the effects of polydatin on rat BMSCs migration using the scratch wound healing and transwell migration assays. Our results showed polydatin could promote BMSCs migration. Further experiments showed activation of ERK 1/2, but not JNK, was required for polydatin-induced BMSCs migration, suggesting that polydatin may promote BMSCs migration via the ERK 1/2 signaling pathways. Taken together, our results indicate that polydatin might be beneficial for stem cell replacement therapy by improving BMSCs migration.

  15. Guided migration of neural stem cells derived from human embryonic stem cells by an electric field.

    Science.gov (United States)

    Feng, Jun-Feng; Liu, Jing; Zhang, Xiu-Zhen; Zhang, Lei; Jiang, Ji-Yao; Nolta, Jan; Zhao, Min

    2012-02-01

    Small direct current (DC) electric fields (EFs) guide neurite growth and migration of rodent neural stem cells (NSCs). However, this could be species dependent. Therefore, it is critical to investigate how human NSCs (hNSCs) respond to EF before any possible clinical attempt. Aiming to characterize the EF-stimulated and guided migration of hNSCs, we derived hNSCs from a well-established human embryonic stem cell line H9. Small applied DC EFs, as low as 16 mV/mm, induced significant directional migration toward the cathode. Reversal of the field polarity reversed migration of hNSCs. The galvanotactic/electrotactic response was both time and voltage dependent. The migration directedness and distance to the cathode increased with the increase of field strength. (Rho-kinase) inhibitor Y27632 is used to enhance viability of stem cells and has previously been reported to inhibit EF-guided directional migration in induced pluripotent stem cells and neurons. However, its presence did not significantly affect the directionality of hNSC migration in an EF. Cytokine receptor [C-X-C chemokine receptor type 4 (CXCR4)] is important for chemotaxis of NSCs in the brain. The blockage of CXCR4 did not affect the electrotaxis of hNSCs. We conclude that hNSCs respond to a small EF by directional migration. Applied EFs could potentially be further exploited to guide hNSCs to injured sites in the central nervous system to improve the outcome of various diseases.

  16. Regulation of epidermal Langerhans cell migration by lactoferrin.

    Science.gov (United States)

    Cumberbatch, M; Dearman, R J; Uribe-Luna, S; Headon, D R; Ward, P P; Conneely, O M; Kimber, I

    2000-05-01

    Lactoferrin (LF) is a member of the transferrin family of iron-binding glycoproteins to which several anti-inflammatory functions have been ascribed. LF has been shown to down-regulate expression of the pro-inflammatory cytokine tumour necrosis factor-alpha (TNF-alpha), although the possibility has been raised that the activity of LF in this regard was indirect and secondary to its ability to bind to and inactivate the bacterial lipopolysaccharide (LPS) used to induce cytokine production. However, the identification of putative membrane receptors for LF raises the possibility that the interaction of LF with its receptor may be one important route through which this protein exerts anti-inflammatory activity. In the present investigations the biological properties of LF have been examined in a model of cutaneous immune function where the allergen-induced migration of epidermal Langerhans cells (LC) from the skin and their subsequent accumulation as dendritic cells (DC) in skin-draining lymph nodes are known to be dependent upon the de novo synthesis of TNF-alpha, but independent of exogenous LPS. Consistent with the protein having direct anti-inflammatory properties, it was found that the intradermal injection of recombinant murine LF (either iron-saturated or iron-depleted LF) inhibited significantly allergen (oxazolone) -induced LC migration and DC accumulation. That these inhibitory effects were secondary to the inhibition of local TNF-alpha synthesis was suggested by the findings that first, LF was unable to inhibit LC migration induced by intradermal injection of TNF-alpha itself, and second, that migration stimulated by local administration of another epidermal cytokine, interleukin 1beta, which is also dependent upon TNF-alpha production, was impaired significantly by prior treatment with LF. Finally, immunohistochemical analyses demonstrated the presence of LF in skin, associated primarily with keratinocytes. Collectively these data support the possession by

  17. Expression and phosphorylation of stathmin correlate with cell migration in esophageal squamous cell carcinoma.

    Science.gov (United States)

    Liu, Fei; Sun, Yu-Lin; Xu, Yang; Liu, Fang; Wang, Li-Shun; Zhao, Xiao-Hang

    2013-02-01

    Microtubules play extensive roles in cellular processes, including cell motility. Stathmin is an important protein which destabilizes microtubules. The essential function of stathmin is closely associated with its phosphorylation status. Stathmin is overexpressed in many human cancers and has a significant relationship with clinical characteristics such as grade, tumor size and prognosis. We demonstrated that stathmin was overexpressed in ESCC tissues using both 2-DE and immunohistochemistry analysis. In addition, overexpression of stathmin was significantly correlated with histological grade in ESCC. However, no correlation was found with age, gender and lymph node metastasis. Knockdown of stathmin with siRNA impaired cell migration in KYSE30 and KYSE410 cells. When EC0156 cells were treated with paclitaxel, stathmin was stably phosphorylated and migration was impaired. These observations suggest that stathmin may have a more important function in ESCC development and migration. The present study provides further understanding of the importance of stathmin in ESCC therapy or diagnosis.

  18. Prostaglandins in Cancer Cell Adhesion, Migration, and Invasion

    Directory of Open Access Journals (Sweden)

    David G. Menter

    2012-01-01

    Full Text Available Prostaglandins exert a profound influence over the adhesive, migratory, and invasive behavior of cells during the development and progression of cancer. Cyclooxygenase-2 (COX-2 and microsomal prostaglandin E2 synthase-1 (mPGES-1 are upregulated in inflammation and cancer. This results in the production of prostaglandin E2 (PGE2, which binds to and activates G-protein-coupled prostaglandin E1-4 receptors (EP1-4. Selectively targeting the COX-2/mPGES-1/PGE2/EP1-4 axis of the prostaglandin pathway can reduce the adhesion, migration, invasion, and angiogenesis. Once stimulated by prostaglandins, cadherin adhesive connections between epithelial or endothelial cells are lost. This enables cells to invade through the underlying basement membrane and extracellular matrix (ECM. Interactions with the ECM are mediated by cell surface integrins by “outside-in signaling” through Src and focal adhesion kinase (FAK and/or “inside-out signaling” through talins and kindlins. Combining the use of COX-2/mPGES-1/PGE2/EP1-4 axis-targeted molecules with those targeting cell surface adhesion receptors or their downstream signaling molecules may enhance cancer therapy.

  19. Brain-derived Neurotrophic Factor Promotes the Migration of Olfactory Ensheathing Cells Through TRPC Channels.

    Science.gov (United States)

    Wang, Ying; Teng, Hong-Lin; Gao, Yuan; Zhang, Fan; Ding, Yu-Qiang; Huang, Zhi-Hui

    2016-12-01

    Olfactory ensheathing cells (OECs) are a unique type of glial cells with axonal growth-promoting properties in the olfactory system. Organized migration of OECs is essential for neural regeneration and olfactory development. However, the molecular mechanism of OEC migration remains unclear. In the present study, we examined the effects of brain-derived neurotrophic factor (BDNF) on OEC migration. Initially, the "scratch" migration assay, the inverted coverslip and Boyden chamber migration assays showed that BDNF could promote the migration of primary cultured OECs. Furthermore, BDNF gradient attracted the migration of OECs in single-cell migration assays. Mechanistically, TrkB receptor expressed in OECs mediated BDNF-induced OEC migration, and BDNF triggered calcium signals in OECs. Finally, transient receptor potential cation channels (TRPCs) highly expressed in OECs were responsible for BDNF-induced calcium signals, and required for BDNF-induced OEC migration. Taken together, these results demonstrate that BDNF promotes the migration of cultured OECs and an unexpected finding is that TRPCs are required for BDNF-induced OEC migration. GLIA 2016;64:2154-2165.

  20. miR-1 Inhibits Cell Growth, Migration, and Invasion by Targeting VEGFA in Osteosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Junjie Niu

    2016-01-01

    Full Text Available microRNAs (miRNAs are small noncoding RNAs and have been shown to play a crucial role in the osteosarcoma (OS tumorigenesis and progression. VEGFA is a key regulator of angiogenesis and plays an important role in regulation of tumor metastasis. The objective of this study was to determine whether VEGFA was involved in miR-1-mediated suppression of proliferation, migration, and invasion of OS cells. The expression levels of miR-1 were significantly lower in OS tumor tissues than those in adjacent normal tissues and in SAOS-2 and U2OS cell lines compared to a normal osteoblast (NHOst cell line. VEGFA was upregulated in OS tumor tissues and SAOS-2 and U2OS cell lines. The results of CCK-8 assay and transwell assay showed that miR-1 acted as a tumor suppressor by inhibiting cell proliferation, migration, and invasion in U2OS cells. Dual luciferase reporter assay demonstrated that VEGFA was a direct and functional target gene of miR-1. miR-1 directly inhibits the protein expression of VEGFA via its 3′-UTR. Knockdown of VEGFA by siRNA inhibited proliferation, migration, and invasion of U2OS cells. Our study suggested the potential inhibitory function of miR-1 in OS cell proliferation, migration, and invasion via inhibiting VEGFA.

  1. A Macroscopic Mathematical Model for Cell Migration Assays Using a Real-Time Cell Analysis.

    Science.gov (United States)

    Di Costanzo, Ezio; Ingangi, Vincenzo; Angelini, Claudia; Carfora, Maria Francesca; Carriero, Maria Vincenza; Natalini, Roberto

    Experiments of cell migration and chemotaxis assays have been classically performed in the so-called Boyden Chambers. A recent technology, xCELLigence Real Time Cell Analysis, is now allowing to monitor the cell migration in real time. This technology measures impedance changes caused by the gradual increase of electrode surface occupation by cells during the course of time and provide a Cell Index which is proportional to cellular morphology, spreading, ruffling and adhesion quality as well as cell number. In this paper we propose a macroscopic mathematical model, based on advection-reaction-diffusion partial differential equations, describing the cell migration assay using the real-time technology. We carried out numerical simulations to compare simulated model dynamics with data of observed biological experiments on three different cell lines and in two experimental settings: absence of chemotactic signals (basal migration) and presence of a chemoattractant. Overall we conclude that our minimal mathematical model is able to describe the phenomenon in the real time scale and numerical results show a good agreement with the experimental evidences.

  2. [Effect of polysaccharides from Radix Glycyrrhizae on migration and polyamines contents of IEC-6 cell].

    Science.gov (United States)

    Wen, Peng; Sui, Jing-Jing; Li, Ru-Liu; Zhao, Shi-Qing; Lu, Wen-Biao; Chen, Wei-Wen

    2012-07-01

    To study the effect of polysaccharides from Radix Glycyrrhizae on migration and polyamines (putrescine, spermidine and spermine) contents of IEC-6 cell. Cell migration model was induced by scratch method in each well,and the polyamines in IEC-6 cell was determined by pre-column derivation high performance liquid chromatography. The polysaccharides inhibited effect on migration and polyamines contents of IEC-6 cells, and on IEC-6 cell migration by DFMO (a polyamines synthesis inhibitor) and the polyamines contents in the cells were observed. The polysaccharides (50 mg/L or 100 mg/L) was able to promote the cell migration, reverse the cell migration inhibition by DFMO, enhance the IEC-6 cell polyamines (putrescine, spermidine and spermine) contents in the process of cell migration and reverse the reduction of polyamines (putrescine, spermidine and spermine) induced by DFMO. The effect of Radix Glycyrrhizae on the gastrointestinal mucosal damage repairing may be related to increasing polyamine content in cells and promoting cell migration.

  3. Crawling and Gliding: A Computational Model for Shape-Driven Cell Migration

    NARCIS (Netherlands)

    Niculescu, I.; Textor, J.C.; Boer, R.J. de

    2015-01-01

    Cell migration is a complex process involving many intracellular and extracellular factors, with different cell types adopting sometimes strikingly different morphologies. Modeling realistically behaving cells in tissues is computationally challenging because it implies dealing with multiple levels

  4. Crawling and Gliding : A Computational Model for Shape-Driven Cell Migration

    NARCIS (Netherlands)

    Niculescu, Ioana; Textor, Johannes; de Boer, Rob J

    2015-01-01

    Cell migration is a complex process involving many intracellular and extracellular factors, with different cell types adopting sometimes strikingly different morphologies. Modeling realistically behaving cells in tissues is computationally challenging because it implies dealing with multiple levels

  5. Fast-crawling cell types migrate to avoid the direction of periodic substratum stretching.

    Science.gov (United States)

    Okimura, Chika; Ueda, Kazuki; Sakumura, Yuichi; Iwadate, Yoshiaki

    2016-07-03

    To investigate the relationship between mechanical stimuli from substrata and related cell functions, one of the most useful techniques is the application of mechanical stimuli via periodic stretching of elastic substrata. In response to this stimulus, Dictyostelium discoideum cells migrate in a direction perpendicular to the stretching direction. The origins of directional migration, higher migration velocity in the direction perpendicular to the stretching direction or the higher probability of a switch of migration direction to perpendicular to the stretching direction, however, remain unknown. In this study, we applied periodic stretching stimuli to neutrophil-like differentiated HL-60 cells, which migrate perpendicular to the direction of stretch. Detailed analysis of the trajectories of HL-60 cells and Dictyostelium cells obtained in a previous study revealed that the higher probability of a switch of migration direction to that perpendicular to the direction of stretching was the main cause of such directional migration. This directional migration appears to be a strategy adopted by fast-crawling cells in which they do not migrate faster in the direction they want to go, but migrate to avoid a direction they do not want to go.

  6. Fast-crawling cell types migrate to avoid the direction of periodic substratum stretching

    Science.gov (United States)

    Okimura, Chika; Ueda, Kazuki; Sakumura, Yuichi; Iwadate, Yoshiaki

    2016-01-01

    ABSTRACT To investigate the relationship between mechanical stimuli from substrata and related cell functions, one of the most useful techniques is the application of mechanical stimuli via periodic stretching of elastic substrata. In response to this stimulus, Dictyostelium discoideum cells migrate in a direction perpendicular to the stretching direction. The origins of directional migration, higher migration velocity in the direction perpendicular to the stretching direction or the higher probability of a switch of migration direction to perpendicular to the stretching direction, however, remain unknown. In this study, we applied periodic stretching stimuli to neutrophil-like differentiated HL-60 cells, which migrate perpendicular to the direction of stretch. Detailed analysis of the trajectories of HL-60 cells and Dictyostelium cells obtained in a previous study revealed that the higher probability of a switch of migration direction to that perpendicular to the direction of stretching was the main cause of such directional migration. This directional migration appears to be a strategy adopted by fast-crawling cells in which they do not migrate faster in the direction they want to go, but migrate to avoid a direction they do not want to go. PMID:26980079

  7. From cell differentiation to cell collectives: Bacillus subtilis uses division of labor to migrate.

    Directory of Open Access Journals (Sweden)

    Jordi van Gestel

    2015-04-01

    Full Text Available The organization of cells, emerging from cell-cell interactions, can give rise to collective properties. These properties are adaptive when together cells can face environmental challenges that they separately cannot. One particular challenge that is important for microorganisms is migration. In this study, we show how flagellum-independent migration is driven by the division of labor of two cell types that appear during Bacillus subtilis sliding motility. Cell collectives organize themselves into bundles (called "van Gogh bundles" of tightly aligned cell chains that form filamentous loops at the colony edge. We show, by time-course microscopy, that these loops migrate by pushing themselves away from the colony. The formation of van Gogh bundles depends critically on the synergistic interaction of surfactin-producing and matrix-producing cells. We propose that surfactin-producing cells reduce the friction between cells and their substrate, thereby facilitating matrix-producing cells to form bundles. The folding properties of these bundles determine the rate of colony expansion. Our study illustrates how the simple organization of cells within a community can yield a strong ecological advantage. This is a key factor underlying the diverse origins of multicellularity.

  8. Integrin-mediated cell migration is blocked by inhibitors of human neuraminidase.

    Science.gov (United States)

    Jia, Feng; Howlader, Md Amran; Cairo, Christopher W

    2016-09-01

    Integrins are critical receptors in cell migration and adhesion. A number of mechanisms are known to regulate the function of integrins, including phosphorylation, conformational change, and cytoskeletal anchoring. We investigated whether native neuraminidase (Neu, or sialidase) enzymes which modify glycolipids could play a role in regulating integrin-mediated cell migration. Using a scratch assay, we found that exogenously added Neu3 and Neu4 activity altered rates of cell migration. We observed that Neu4 increased the rate of migration in two cell lines (HeLa, A549); while Neu3 only increased migration in HeLa cells. A bacterial neuraminidase was able to increase the rate of migration in HeLa, but not in A549 cells. Treatment of cells with complex gangliosides (GM1, GD1a, GD1b, and GT1b) resulted in decreased cell migration rates, while LacCer was able to increase rates of migration in both lines. Importantly, our results show that treatment of cells with inhibitors of native Neu enzymes had a dramatic effect on the rates of cell migration. The most potent compound tested targeted the human Neu4 isoenzyme, and was able to substantially reduce the rate of cell migration. We found that the lateral mobility of integrins was reduced by treatment of cells with Neu3, suggesting that Neu3 enzyme activity resulted in changes to integrin-co-receptor or integrin-cytoskeleton interactions. Finally, our results support the hypothesis that inhibitors of human Neu can be used to investigate mechanisms of cell migration and for the development of anti-adhesive therapies.

  9. Predictive estimation of upward pollutant migration during shale gas production using satellite image processing

    Science.gov (United States)

    Lyalko, Vadim; Azimov, Oleksandr; Yakovlev, Yevgen

    2016-07-01

    The report considers the relevance of the application of modern remote aerospace and hydrogeological methods in the problems of the ecological safety for the hydrosphere during shale gas production in Ukraine. Case studies of pilot implementation of these methods are present for the Bilyaivska area adjacent to the Yuzivka licensed site within the Dnieper-Donets Depression. A number of the hydrogeological filtration parameters and the thematic processing for remote sensing data of the Earth enable to obtain the rough estimate of the temporal indices for the upward pollutant migration from the fracturing zone to the groundwater aquifers in the potential process of shale gas production (as an example the 400-Bilyaivska well). It is found that the possible variety of the active permeability in tectonic zone, which may be predicted by using remote sensing of the Earth image interpretation in vicinity of the well, is responsible for the passage time of pollution from the fracturing zone level to the groundwater aquifers one and this time interval spans 50˜5 years.

  10. ERP44 inhibits human lung cancer cell migration mainly via IP3R2.

    Science.gov (United States)

    Huang, Xue; Jin, Meng; Chen, Ying-Xiao; Wang, Jun; Zhai, Kui; Chang, Yan; Yuan, Qi; Yao, Kai-Tai; Ji, Guangju

    2016-06-01

    Cancer cell migration is involved in tumour metastasis. However, the relationship between calcium signalling and cancer migration is not well elucidated. In this study, we used the human lung adenocarcinoma A549 cell line to examine the role of endoplasmic reticulum protein 44 (ERP44), which has been reported to regulate calcium release inside of the endoplasmic reticulum (ER), in cell migration. We found that the inositol 1,4,5-trisphosphate receptors (IP3Rs/ITPRs) inhibitor 2-APB significantly inhibited A549 cell migration by inhibiting cell polarization and pseudopodium protrusion, which suggests that Ca2+ is necessary for A549 cell migration. Similarly, the overexpression of ERP44 reduced intracellular Ca2+ release via IP3Rs, altered cell morphology and significantly inhibited the migration of A549 cells. These phenomena were primarily dependent on IP3R2 because wound healing in A549 cells with IP3R2 rather than IP3R1 or IP3R3 siRNA was markedly inhibited. Moreover, the overexpression of ERP44 did not affect the migration of the human neuroblastoma cell line SH-SY5Y, which mainly expresses IP3R1. Based on the above observations, we conclude that ERP44 regulates A549 cell migration mainly via an IP3R2-dependent pathway.

  11. Computational modelling of cell chain migration reveals mechanisms that sustain follow-the-leader behaviour.

    Science.gov (United States)

    Wynn, Michelle L; Kulesa, Paul M; Schnell, Santiago

    2012-07-07

    Follow-the-leader chain migration is a striking cell migratory behaviour observed during vertebrate development, adult neurogenesis and cancer metastasis. Although cell-cell contact and extracellular matrix (ECM) cues have been proposed to promote this phenomenon, mechanisms that underlie chain migration persistence remain unclear. Here, we developed a quantitative agent-based modelling framework to test mechanistic hypotheses of chain migration persistence. We defined chain migration and its persistence based on evidence from the highly migratory neural crest model system, where cells within a chain extend and retract filopodia in short-lived cell contacts and move together as a collective. In our agent-based simulations, we began with a set of agents arranged as a chain and systematically probed the influence of model parameters to identify factors critical to the maintenance of the chain migration pattern. We discovered that chain migration persistence requires a high degree of directional bias in both lead and follower cells towards the target. Chain migration persistence was also promoted when lead cells maintained cell contact with followers, but not vice-versa. Finally, providing a path of least resistance in the ECM was not sufficient alone to drive chain persistence. Our results indicate that chain migration persistence depends on the interplay of directional cell movement and biased cell-cell contact.

  12. Cell surface activation of progelatinase A (proMMP—2) and cell migration

    Institute of Scientific and Technical Information of China (English)

    NAGASEHIDEAKI

    1998-01-01

    Gelatinase A (MMP-2) is considered to play a critical role in cell migration and invasion.The proteinase is cerceted from the cell as an inactive zymogen.In vivo it is postulated that activation of progelationase A (proMMP-2) takes place on the cell surface mediated by membrane-type matrix metalloproteinases (MT-MMPs).Recent studies have demonstrated that proMMP-2 is recruited to the cell surface by interacting with tissue inhibitor of metalloproteinases-2 (TIMP-2) bound to MT1-MMP by forming a ternary complex.Free MT1-MMP closely located to the ternary complex then activates proMMP-2 on the cell surface.MT1-MMP is found in cultured invasive cancer cells at the invadopodia.The MT-MMP/TIMP-2/MMP-2 system thus provides localized expression of proteolysis of the extracellular matrix required for cell migration.

  13. Modeling the Jovian subnebula: I - Thermodynamical conditions and migration of proto-satellites

    CERN Document Server

    Alibert, Y; Benz, W; Alibert, Yann; Mousis, Olivier; Benz, Willy

    2005-01-01

    We have developed an evolutionary turbulent model of the Jovian subnebula consistent with the extended core accretion formation models of Jupiter described by Alibert et al. (2005b) and derived from Alibert et al. (2004,2005a). This model takes into account the vertical structure of the subnebula, as well as the evolution of the surface density as given by an $\\alpha$-disk model and is used to calculate the thermodynamical conditions in the subdisk, for different values of the viscosity parameter. We show that the Jovian subnebula evolves in two different phases during its lifetime. In the first phase, the subnebula is fed through its outer edge by the solar nebula as long as it has not been dissipated. In the second phase, the solar nebula has disappeared and the Jovian subdisk expands and gradually clears with time as Jupiter accretes the remaining material. We also demonstrate that early generations of satellites formed during the beginning of the first phase of the subnebula cannot survive in this environ...

  14. Specific Myosins Control Actin Organization, Cell Morphology, and Migration in Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Katarzyna A. Makowska

    2015-12-01

    Full Text Available We investigated the myosin expression profile in prostate cancer cell lines and found that Myo1b, Myo9b, Myo10, and Myo18a were expressed at higher levels in cells with high metastatic potential. Moreover, Myo1b and Myo10 were expressed at higher levels in metastatic tumors. Using an siRNA-based approach, we found that knockdown of each myosin resulted in distinct phenotypes. Myo10 knockdown ablated filopodia and decreased 2D migration speed. Myo18a knockdown increased circumferential non-muscle myosin 2A-associated actin filament arrays in the lamella and reduced directional persistence of 2D migration. Myo9b knockdown increased stress fiber formation, decreased 2D migration speed, and increased directional persistence. Conversely, Myo1b knockdown increased numbers of stress fibers but did not affect 2D migration. In all cases, the cell spread area was increased and 3D migration potential was decreased. Therefore, myosins not only act as molecular motors but also directly influence actin organization and cell morphology, which can contribute to the metastatic phenotype.

  15. Modulation of epithelial tissue and cell migration by microgrooves.

    NARCIS (Netherlands)

    Dalton, B.A.; Walboomers, X.F.; Dziegielewski, M.; Evans, M.D.; Taylor, S.; Jansen, J.A.; Steele, J.G.

    2001-01-01

    We used a polystyrene substratum to study the response of migrating epithelium to 1- or 5-microm depth microgrooves with groove/ridge widths of 1, 2, 5, or 10 microm. The migration of a tissue sheet was enhanced along the microgrooves, while migration across the microgrooves was inhibited. Changing

  16. Insulin-producing cells from embryonic stem cells rescues hyperglycemia via intra-spleen migration.

    Science.gov (United States)

    Ren, Meng; Shang, Changzhen; Zhong, Xiaomei; Guo, Ruomi; Lao, Guojuan; Wang, Xiaoyi; Cheng, Hua; Min, Jun; Yan, Li; Shen, Jun

    2014-12-23

    Implantation of embryonic stem cells (ESC)-derived insulin-producing cells has been extensively investigated for treatment of diabetes in animal models. However, the in vivo behavior and migration of transplanted cells in diabetic models remains unclear. Here we investigated the location and migration of insulin-producing cells labeled with superparamagnetic iron oxide (SPIO) using a dynamic MRI tracking method. SPIO labeled cells showed hypointense signal under the kidney subcapsules of diabetic mice on MRI, and faded gradually over the visiting time. However, new hypointense signal appeared in the spleen 1 week after transplantation, and became obvious with the time prolongation. Further histological examination proved the immigrated cells were insulin and C-peptide positive cells which were evenly distributed throughout the spleen. These intra-spleen insulin-producing cells maintained their protective effects against hyperglycemia in vivo, and these effects were reversed upon spleen removal. Transplantation of insulin-producing cells through spleen acquired an earlier blood glucose control as compared with that through kidney subcapsules. In summary, our data demonstrate that insulin-producing cells transplanted through kidney subcapsules were not located in situ but migrated into spleen, and rescues hyperglycemia in diabetic models. MRI may provide a novel tracking method for preclinical cell transplantation therapy of diabetes continuously and non-invasively.

  17. Computational modelling of multi-cell migration in a multi-signalling substrate

    Science.gov (United States)

    Jamaleddin Mousavi, Seyed; Doblaré, Manuel; Hamdy Doweidar, Mohamed

    2014-04-01

    Cell migration is a vital process in many biological phenomena ranging from wound healing to tissue regeneration. Over the past few years, it has been proven that in addition to cell-cell and cell-substrate mechanical interactions (mechanotaxis), cells can be driven by thermal, chemical and/or electrical stimuli. A numerical model was recently presented by the authors to analyse single cell migration in a multi-signalling substrate. That work is here extended to include multi-cell migration due to cell-cell interaction in a multi-signalling substrate under different conditions. This model is based on balancing the forces that act on the cell population in the presence of different guiding cues. Several numerical experiments are presented to illustrate the effect of different stimuli on the trajectory and final location of the cell population within a 3D heterogeneous multi-signalling substrate. Our findings indicate that although multi-cell migration is relatively similar to single cell migration in some aspects, the associated behaviour is very different. For instance, cell-cell interaction may delay single cell migration towards effective cues while increasing the magnitude of the average net cell traction force as well as the local velocity. Besides, the random movement of a cell within a cell population is slightly greater than that of single cell migration. Moreover, higher electrical field strength causes the cell slug to flatten near the cathode. On the other hand, as with single cell migration, the existence of electrotaxis dominates mechanotaxis, moving the cells to the cathode or anode pole located at the free surface. The numerical results here obtained are qualitatively consistent with related experimental works.

  18. Overexpression of Dishevelled-2 contributes to proliferation and migration of human esophageal squamous cell carcinoma.

    Science.gov (United States)

    Zhou, Guoren; Ye, Jinjun; Sun, Lei; Zhang, Zhi; Feng, Jifeng

    2016-06-01

    Dishevelled-2 (Dvl2) was associated with tumor cell proliferation and migration. We aimed to examine the mechanism of Dvl2 in esophageal squamous cell carcinoma (ESCC). Dvl2 was overexpressed in human ESCC tissues and cell lines ECA109 and TE1 cells. CCK-8 and colony formation assay was performed to evaluate the proliferation in ECA109 cells transfected with Dvl2-shRNA. Wound-healing assay and transwell assay were used to examine the activities of migration and invasion in Dvl2-silenced ESCC cells. Knockdown of Dvl2 significantly reduced ECA109 cell proliferation and migration. Moreover, we demonstrated that the proliferation and migration ability of Dvl2 might through the activation of Wnt pathway by targeting the Cyclin D1 and MMP-9. We came to the conclusion that the proliferation and migration effects of Dvl2 might contribute to malignant development of human ESCC.

  19. Microbial desalination cell with capacitive adsorption for ion migration control.

    Science.gov (United States)

    Forrestal, Casey; Xu, Pei; Jenkins, Peter E; Ren, Zhiyong

    2012-09-01

    A new microbial desalination cell with capacitive adsorption capability (cMDC) was developed to solve the ion migration problem facing current MDC systems. Traditional MDCs remove salts by transferring ions to the anode and cathode chambers, which may prohibit wastewater beneficial reuse due to increased salinity. The cMDC uses adsorptive activated carbon cloth (ACC) as the electrodes and utilizes the formed capacitive double layers for electrochemical ion adsorption. The cMDC removed an average of 69.4% of the salt from the desalination chamber through electrode adsorption during one batch cycle, and it did not add salts to the anode or cathode chamber. It was estimated that 61-82.2mg of total dissolved solids (TDS) was adsorbed to 1g of ACC electrode. The cMDC provides a new approach for salt management, organic removal, and energy production. Further studies will be conducted to optimize reactor configuration and achieve in situ electrode regeneration.

  20. Leader cells regulate collective cell migration via Rac activation in the downstream signaling of integrin beta 1 and PI3K

    OpenAIRE

    YAMAGUCHI, Naoya; Mizutani, Takeomi; Kawabata, Kazushige; Haga, Hisashi

    2015-01-01

    Collective cell migration plays a crucial role in several biological processes, such as embryonic development, wound healing, and cancer metastasis. Here, we focused on collectively migrating Madin-Darby Canine Kidney (MDCK) epithelial cells that follow a leader cell on a collagen gel to clarify the mechanism of collective cell migration. First, we removed a leader cell from the migrating collective with a micromanipulator. This then caused disruption of the cohesive migration of cells that f...

  1. Impaired SIRT1 promotes the migration of vascular smooth muscle cell-derived foam cells.

    Science.gov (United States)

    Zhang, Ming-Jie; Zhou, Yi; Chen, Lei; Wang, Xu; Pi, Yan; Long, Chun-Yan; Sun, Meng-Jiao; Chen, Xue; Gao, Chang-Yue; Li, Jing-Cheng; Zhang, Li-Li

    2016-07-01

    The formation of fat-laden foam cells, contributing to the fatty streaks of the plaques of atheroma, is the critical early process in atherosclerosis. The previous study demonstrated that vascular smooth muscle cells (VSMCs) contain a much larger burden of the excess cholesterol in comparison with monocyte-derived macrophages in human coronary atherosclerosis, as the main origin of foam cells. It is noteworthy that VSMC-derived foam cells are deposited in subintima but not media, where VSMCs normally deposit in. Therefore, migration from media to intima is an indispensable step for a VSMC to accrue neutral lipids and form foam cell. Whether this migration occurs paralleled with or prior to the formation of foam cell is still unclear. Herein, the present study was designed to test the VSMC migratory capability in the process of foam cell formation induced by oxidized low-density lipoprotein (oxLDL). In conclusion, we provide evidence that oxLDL induces the VSMC-derived foam cells formation with increased migration ability and MMP-9 expression, which were partly attributed to the impaired SIRT1 and enhanced nuclear factor-kappa B (NF-κB) activity. As activation of transient receptor potential vanilloid type 1 (TRPV1) has been reported to have anti-atherosclerotic effects, we investigated its role in oxLDL-treated VSMC migration. It is found that activating TRPV1 by capsaicin inhibits VSMC foam cell formation and the accompanied migration through rescuing the SIRT1 and suppressing NF-κB signaling. The present study provides evidence that SIRT1 may be a promising intervention target of atherosclerosis, and raises the prospect of TRPV1 in prevention and treatment of atherosclerosis.

  2. Continual Cell Deformation Induced via Attachment to Oriented Fibers Enhances Fibroblast Cell Migration

    Science.gov (United States)

    Qin, Sisi; Ricotta, Vincent; Simon, Marcia; Clark, Richard A. F.; Rafailovich, Miriam H.

    2015-01-01

    Fibroblast migration is critical to the wound healing process. In vivo, migration occurs on fibrillar substrates, and previous observations have shown that a significant time lag exists before the onset of granulation tissue. We therefore conducted a series of experiments to understand the impact of both fibrillar morphology and migration time. Substrate topography was first shown to have a profound influence. Fibroblasts preferentially attach to fibrillar surfaces, and orient their cytoplasm for maximal contact with the fiber edge. In the case of en-mass cell migration out of an agarose droplet, fibroblasts on flat surfaces emerged with an enhanced velocity, v = 52μm/h, that decreases to the single cell value, v = 28μm/h within 24 hours and remained constant for at least four days. Fibroblasts emerging on fibrillar surfaces emerged with the single cell velocity, which remained constant for the first 24 hours and then increased reaching a plateau with more than twice the initial velocity within the next three days. The focal adhesions were distributed uniformly in cells on flat surfaces, while on the fibrillar surface they were clustered along the cell periphery. Furthermore, the number of focal adhesions for the cells on the flat surfaces remained constant, while it decreased on the fibrillar surface during the next three days. The deformation of the cell nuclei was found to be 50% larger on the fiber surfaces for the first 24 hours. While the mean deformation remained constant on the flat surface, it increased for the next three days by 24% in cells on fibers. On the fourth day, large actin/myosin fibers formed in cells on fibrillar surfaces only and coincided with a change from the standard migration mechanism involving extension of lamellipodia, and retraction of the rear, to one involving strong contractions oriented along the fibers and centered about the nucleus. PMID:25774792

  3. Continual cell deformation induced via attachment to oriented fibers enhances fibroblast cell migration.

    Directory of Open Access Journals (Sweden)

    Sisi Qin

    Full Text Available Fibroblast migration is critical to the wound healing process. In vivo, migration occurs on fibrillar substrates, and previous observations have shown that a significant time lag exists before the onset of granulation tissue. We therefore conducted a series of experiments to understand the impact of both fibrillar morphology and migration time. Substrate topography was first shown to have a profound influence. Fibroblasts preferentially attach to fibrillar surfaces, and orient their cytoplasm for maximal contact with the fiber edge. In the case of en-mass cell migration out of an agarose droplet, fibroblasts on flat surfaces emerged with an enhanced velocity, v = 52μm/h, that decreases to the single cell value, v = 28μm/h within 24 hours and remained constant for at least four days. Fibroblasts emerging on fibrillar surfaces emerged with the single cell velocity, which remained constant for the first 24 hours and then increased reaching a plateau with more than twice the initial velocity within the next three days. The focal adhesions were distributed uniformly in cells on flat surfaces, while on the fibrillar surface they were clustered along the cell periphery. Furthermore, the number of focal adhesions for the cells on the flat surfaces remained constant, while it decreased on the fibrillar surface during the next three days. The deformation of the cell nuclei was found to be 50% larger on the fiber surfaces for the first 24 hours. While the mean deformation remained constant on the flat surface, it increased for the next three days by 24% in cells on fibers. On the fourth day, large actin/myosin fibers formed in cells on fibrillar surfaces only and coincided with a change from the standard migration mechanism involving extension of lamellipodia, and retraction of the rear, to one involving strong contractions oriented along the fibers and centered about the nucleus.

  4. Microtubules and Lis-1/NudE/dynein regulate invasive cell-on-cell migration in Drosophila.

    Directory of Open Access Journals (Sweden)

    Nachen Yang

    Full Text Available The environment through which cells migrate in vivo differs considerably from the in vitro environment where cell migration is often studied. In vivo many cells migrate in crowded and complex 3-dimensional tissues and may use other cells as the substratum on which they move. This includes neurons, glia and their progenitors in the brain. Here we use a Drosophila model of invasive, collective migration in a cellular environment to investigate the roles of microtubules and microtubule regulators in this type of cell movement. Border cells are of epithelial origin and have no visible microtubule organizing center (MTOC. Interestingly, microtubule plus-end growth was biased away from the leading edge. General perturbation of the microtubule cytoskeleton and analysis by live imaging showed that microtubules in both the migrating cells and the substrate cells affect movement. Also, whole-tissue and cell autonomous deletion of the microtubule regulator Stathmin had distinct effects. A screen of 67 genes encoding microtubule interacting proteins uncovered cell autonomous requirements for Lis-1, NudE and Dynein in border cell migration. Net cluster migration was decreased, with initiation of migration and formation of dominant front cell protrusion being most dramatically affected. Organization of cells within the cluster and localization of cell-cell adhesion molecules were also abnormal. Given the established role of Lis-1 in migrating neurons, this could indicate a general role of Lis-1/NudE, Dynein and microtubules, in cell-on-cell migration. Spatial regulation of cell-cell adhesion may be a common theme, consistent with observing both cell autonomous and non-autonomous requirements in both systems.

  5. The acetylenic tricyclic bis(cyano enone), TBE-31, targets microtubule dynamics and cell polarity in migrating cells.

    Science.gov (United States)

    Chan, Eddie; Saito, Akira; Honda, Tadashi; Di Guglielmo, Gianni M

    2016-04-01

    Cell migration is dependent on the microtubule network for structural support as well as for the proper delivery and positioning of polarity proteins at the leading edge of migrating cells. Identification of drugs that target cytoskeletal-dependent cell migration and protein transport in polarized migrating cells is important in understanding the cell biology of normal and tumor cells and can lead to new therapeutic targets in disease processes. Here, we show that the tricyclic compound TBE-31 directly binds to tubulin and interferes with microtubule dynamics, as assessed by end binding 1 (EB1) live cell imaging. Interestingly, this interference is independent of in vitro tubulin polymerization. Using immunofluorescence microscopy, we also observed that TBE-31 interferes with the polarity of migratory cells. The polarity proteins Rac1, IQGAP and Tiam1 were localized at the leading edge of DMSO-treated migrating cell, but were observed to be in multiple protrusions around the cell periphery of TBE-31-treated cells. Finally, we observed that TBE-31 inhibits the migration of Rat2 fibroblasts with an IC50 of 0.75 μM. Taken together, our results suggest that the inhibition of cell migration by TBE-31 may result from the improper maintenance of cell polarity of migrating cells.

  6. Confinement and low adhesion induce fast amoeboid migration of slow mesenchymal cells.

    Science.gov (United States)

    Liu, Yan-Jun; Le Berre, Maël; Lautenschlaeger, Franziska; Maiuri, Paolo; Callan-Jones, Andrew; Heuzé, Mélina; Takaki, Tohru; Voituriez, Raphaël; Piel, Matthieu

    2015-02-12

    The mesenchymal-amoeboid transition (MAT) was proposed as a mechanism for cancer cells to adapt their migration mode to their environment. While the molecular pathways involved in this transition are well documented, the role of the microenvironment in the MAT is still poorly understood. Here, we investigated how confinement and adhesion affect this transition. We report that, in the absence of focal adhesions and under conditions of confinement, mesenchymal cells can spontaneously switch to a fast amoeboid migration phenotype. We identified two main types of fast migration--one involving a local protrusion and a second involving a myosin-II-dependent mechanical instability of the cell cortex that leads to a global cortical flow. Interestingly, transformed cells are more prone to adopt this fast migration mode. Finally, we propose a generic model that explains migration transitions and predicts a phase diagram of migration phenotypes based on three main control parameters: confinement, adhesion, and contractility.

  7. Chemotactic migration of T cells towards dendritic cells promotes the detection of rare antigens.

    Science.gov (United States)

    Vroomans, Renske M A; Marée, Athanasius F M; de Boer, Rob J; Beltman, Joost B

    2012-01-01

    In many immunological processes chemoattraction is thought to play a role in guiding cells to their sites of action. However, based on in vivo two-photon microscopy experiments in the absence of cognate antigen, T cell migration in lymph nodes (LNs) has been roughly described as a random walk. Although it has been shown that dendritic cells (DCs) carrying cognate antigen in some circumstances attract T cells chemotactically, it is currently still unclear whether chemoattraction of T cells towards DCs helps or hampers scanning. Chemoattraction towards DCs could on the one hand help T cells to rapidly find DCs. On the other hand, it could be deleterious if DCs become shielded by a multitude of attracted yet non-specific T cells. Results from a recent simulation study suggested that the deleterious effect dominates. We re-addressed the question whether T cell chemoattraction towards DCs is expected to promote or hamper the detection of rare antigens using the Cellular Potts Model, a formalism that allows for dynamic, flexible cellular shapes and cell migration. Our simulations show that chemoattraction of T cells enhances the DC scanning efficiency, leading to an increased probability that rare antigen-specific T cells find DCs carrying cognate antigen. Desensitization of T cells after contact with a DC further improves the scanning efficiency, yielding an almost threefold enhancement compared to random migration. Moreover, the chemotaxis-driven migration still roughly appears as a random walk, hence fine-tuned analysis of cell tracks will be required to detect chemotaxis within microscopy data.

  8. Chemotactic migration of T cells towards dendritic cells promotes the detection of rare antigens.

    Directory of Open Access Journals (Sweden)

    Renske M A Vroomans

    Full Text Available In many immunological processes chemoattraction is thought to play a role in guiding cells to their sites of action. However, based on in vivo two-photon microscopy experiments in the absence of cognate antigen, T cell migration in lymph nodes (LNs has been roughly described as a random walk. Although it has been shown that dendritic cells (DCs carrying cognate antigen in some circumstances attract T cells chemotactically, it is currently still unclear whether chemoattraction of T cells towards DCs helps or hampers scanning. Chemoattraction towards DCs could on the one hand help T cells to rapidly find DCs. On the other hand, it could be deleterious if DCs become shielded by a multitude of attracted yet non-specific T cells. Results from a recent simulation study suggested that the deleterious effect dominates. We re-addressed the question whether T cell chemoattraction towards DCs is expected to promote or hamper the detection of rare antigens using the Cellular Potts Model, a formalism that allows for dynamic, flexible cellular shapes and cell migration. Our simulations show that chemoattraction of T cells enhances the DC scanning efficiency, leading to an increased probability that rare antigen-specific T cells find DCs carrying cognate antigen. Desensitization of T cells after contact with a DC further improves the scanning efficiency, yielding an almost threefold enhancement compared to random migration. Moreover, the chemotaxis-driven migration still roughly appears as a random walk, hence fine-tuned analysis of cell tracks will be required to detect chemotaxis within microscopy data.

  9. Cell-autonomous and environmental contributions to the interstitial migration of T cells.

    Science.gov (United States)

    Mrass, Paulus; Petravic, Janka; Davenport, Miles P; Weninger, Wolfgang

    2010-09-01

    A key to understanding the functioning of the immune system is to define the mechanisms that facilitate directed lymphocyte migration to and within tissues. The recent development of improved imaging technologies, most prominently multi-photon microscopy, has enabled the dynamic visualization of immune cells in real-time directly within intact tissues. Intravital imaging approaches have revealed high spontaneous migratory activity of T cells in secondary lymphoid organs and inflamed tissues. Experimental evidence points towards both environmental and cell-intrinsic cues involved in the regulation of lymphocyte motility in the interstitial space. Based on these data, several conceptually distinct models have been proposed in order to explain the coordination of lymphocyte migration both at the single cell and population level. These range from "stochastic" models, where chance is the major driving force, to "deterministic" models, where the architecture of the microenvironment dictates the migratory trajectory of cells. In this review, we focus on recent advances in understanding naïve and effector T cell migration in vivo. In addition, we discuss some of the contradictory experimental findings in the context of theoretical models of migrating leukocytes.

  10. ANKHD1 silencing inhibits Stathmin 1 activity, cell proliferation and migration of leukemia cells.

    Science.gov (United States)

    Machado-Neto, João Agostinho; Lazarini, Mariana; Favaro, Patricia; de Melo Campos, Paula; Scopim-Ribeiro, Renata; Franchi Junior, Gilberto Carlos; Nowill, Alexandre Eduardo; Lima, Paulo Roberto Moura; Costa, Fernando Ferreira; Benichou, Serge; Olalla Saad, Sara Teresinha; Traina, Fabiola

    2015-03-01

    ANKHD1 is highly expressed in human acute leukemia cells and potentially regulates multiple cellular functions through its ankyrin-repeat domains. In order to identify interaction partners of the ANKHD1 protein and its role in leukemia cells, we performed a yeast two-hybrid system screen and identified SIVA, a cellular protein known to be involved in proapoptotic signaling pathways. The interaction between ANKHD1 and SIVA was confirmed by co-imunoprecipitation assays. Using human leukemia cell models and lentivirus-mediated shRNA approaches, we showed that ANKHD1 and SIVA proteins have opposing effects. While it is known that SIVA silencing promotes Stathmin 1 activation, increased cell migration and xenograft tumor growth, we showed that ANKHD1 silencing leads to Stathmin 1 inactivation, reduced cell migration and xenograft tumor growth, likely through the inhibition of SIVA/Stathmin 1 association. In addition, we observed that ANKHD1 knockdown decreases cell proliferation, without modulating apoptosis of leukemia cells, while SIVA has a proapoptotic function in U937 cells, but does not modulate proliferation in vitro. Results indicate that ANKHD1 binds to SIVA and has an important role in inducing leukemia cell proliferation and migration via the Stathmin 1 pathway. ANKHD1 may be an oncogene and participate in the leukemia cell phenotype.

  11. PLACENTAL SECRETORY FACTORS INFLUENCE TO THP-1 CELLS PHENOTYPE AND THP-1 CELLS TRANSENDOTHELIAL MIGRATION

    Directory of Open Access Journals (Sweden)

    O. I. Stepanova

    2013-01-01

    Full Text Available Decidual and placental macrophage pools are renewed due to its transendothelial monocyte migration from peripheral blood. Tissue macrophages control placental development and provide fetomaternal immunological tolerance. Preeclamptic pregnancy is accompanied by increased monocyte migration to decidual tissue and local inflammatory events. Regulatory mechanisms of monocyte recruitment to placental and decidual tissues is still unclear. Therefore we investigated the influence soluble placental factors (SPFs during the first- and third-trimester normal pregnancy, as compared to effects of these factors in preeclamptic pregnancy. We studied biological actions of SPF upon transendothelial migration of monocyte-like THP-1 cells and their phenotypic pattern. Transendothelial migration of THP-1 cells was more intensive with firsttrimester SPFs from normal pregnancy, when compared with third-trimester samples, and it was accompanied by decreased CD11a expression. SPFs from pre-eclamptic pregnancy caused an increase in transendothelial migration of THP-1 cells, as compared to SPFs from normal pregnancies, being accompanied by increased CD11b expression. The present study was supported by grants ГК №  02.740.11.0711, НШ-3594.2010.7, МД-150.2011.7 and a grant from St.-Petersburg Goverment for young scientists.

  12. ProBDNF inhibits collective migration and chemotaxis of rat Schwann cells.

    Science.gov (United States)

    Ding, You-Quan; Li, Xuan-Yang; Xia, Guan-Nan; Ren, Hong-Yi; Zhou, Xin-Fu; Su, Bing-Yin; Qi, Jian-Guo

    2016-10-01

    Schwann cell migration, including collective migration and chemotaxis, is essential for the formation of coordinate interactions between Schwann cells and axons during peripheral nerve development and regeneration. Moreover, limited migration of Schwann cells imposed a serious obstacle on Schwann cell-astrocytes intermingling and spinal cord repair after Schwann cell transplantation into injured spinal cords. Recent studies have shown that mature brain-derived neurotrophic factor, a member of the neurotrophin family, inhibits Schwann cell migration. The precursor form of brain-derived neurotrophic factor, proBDNF, was expressed in the developing or degenerating peripheral nerves and the injured spinal cords. Since "the yin and yang of neurotrophin action" has been established as a common sense, proBDNF would be expected to promote Schwann cell migration. However, we found, in the present study, that exogenous proBDNF also inhibited in vitro collective migration and chemotaxis of RSC 96 cells, a spontaneously immortalized rat Schwann cell line. Moreover, proBDNF suppressed adhesion and spreading of those cells. At molecular level, proBDNF inhibits F-actin polymerization and focal adhesion dynamics in cultured RSC 96 cells. Therefore, our results suggested a special case against the classical opinion of "the yin and yang of neurotrophin action" and implied that proBDNF might modulate peripheral nerve development or regeneration and spinal cord repair through perturbing native or transplanted Schwann cell migration.

  13. RBP-J (Rbpsuh) is essential to maintain muscle progenitor cells and to generate satellite cells.

    Science.gov (United States)

    Vasyutina, Elena; Lenhard, Diana C; Wende, Hagen; Erdmann, Bettina; Epstein, Jonathan A; Birchmeier, Carmen

    2007-03-13

    In the developing muscle, a pool of myogenic progenitor cells is formed and maintained. These resident progenitors provide a source of cells for muscle growth in development and generate satellite cells in the perinatal period. By the use of conditional mutagenesis in mice, we demonstrate here that the major mediator of Notch signaling, the transcription factor RBP-J, is essential to maintain this pool of progenitor cells in an undifferentiated state. In the absence of RBP-J, these cells undergo uncontrolled myogenic differentiation, leading to a depletion of the progenitor pool. This results in a lack of muscle growth in development and severe muscle hypotrophy. In addition, satellite cells are not formed late in fetal development in conditional RBP-J mutant mice. We conclude that RBP-J is required in the developing muscle to set aside proliferating progenitors and satellite cells.

  14. Muscle Interstitial Cells: A Brief Field Guide to Non-satellite Cell Populations in Skeletal Muscle.

    Science.gov (United States)

    Tedesco, Francesco Saverio; Moyle, Louise A; Perdiguero, Eusebio

    2017-01-01

    Skeletal muscle regeneration is mainly enabled by a population of adult stem cells known as satellite cells. Satellite cells have been shown to be indispensable for adult skeletal muscle repair and regeneration. In the last two decades, other stem/progenitor cell populations resident in the skeletal muscle interstitium have been identified as "collaborators" of satellite cells during regeneration. They also appear to have a key role in replacing skeletal muscle with adipose, fibrous, or bone tissue in pathological conditions. Here, we review the role and known functions of these different interstitial skeletal muscle cell types and discuss their role in skeletal muscle tissue homeostasis, regeneration, and disease, including their therapeutic potential for cell transplantation protocols.

  15. Matrix Metalloproteinase 9 Secreted by Hypoxia Cardiac Fibroblasts Triggers Cardiac Stem Cell Migration In Vitro

    Directory of Open Access Journals (Sweden)

    Qing Gao

    2015-01-01

    Full Text Available Cessation of blood supply due to myocardial infarction (MI leads to complicated pathological alteration in the affected regions. Cardiac stem cells (CSCs migration plays a major role in promoting recovery of cardiac function and protecting cardiomyocytes in post-MI remodeling. Despite being the most abundant cell type in the mammalian heart, cardiac fibroblasts (CFs were underestimated in the mechanism of CSCs migration. Our objective in this study is therefore to investigate the migration related factors secreted by hypoxia CFs in vitro and the degree that they contribute to CSCs migration. We found that supernatant from hypoxia induced CFs could accelerate CSCs migration. Four migration-related cytokines were reported upregulated both in mRNA and protein levels. Upon adding antagonists of these cytokines, the number of migration cells significantly declined. When the cocktail antagonists of all above four cytokines were added, the migration cells number reduced to the minimum level. Besides, MMP-9 had an important effect on triggering CSCs migration. As shown in our results, MMP-9 induced CSCs migration and the underlying mechanism might involve TNF-α signaling which induced VEGF and MMP-9 expression.

  16. The mechanism for primordial germ-cell migration is conserved between Japanese eel and zebrafish.

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    Taiju Saito

    Full Text Available Primordial germ cells (PGCs are segregated and specified from somatic cells during early development. These cells arise elsewhere and have to migrate across the embryo to reach developing gonadal precursors. Several molecules associated with PGC migration (i.e. dead-end, nanos1, and cxcr4 are highly conserved across phylum boundaries. However, since cell migration is a complicated process that is regulated spatially and temporally by multiple adaptors and signal effectors, the process is unlikely to be explained by these known genes only. Indeed, it has been shown that there are variations in PGC migration pattern during development among teleost species. However, it is still unclear whether the actual mechanism of PGC migration is conserved among species. In this study, we studied the migration of PGCs in Japanese eel (Anguilla japonica embryos and tested the migration mechanism between Japanese eel and zebrafish (Danio rerio for conservation, by transplanting eel PGCs into zebrafish embryos. The experiments showed that eel PGCs can migrate toward the gonadal region of zebrafish embryos along with endogenous PGCs, even though the migration patterns, behaviors, and settlements of PGCs are somewhat different between these species. Our results demonstrate that the migration mechanism of PGCs during embryonic development is highly conserved between these two distantly related species (belonging to different teleost orders.

  17. Nonpolarized signaling reveals two distinct modes of 3D cell migration.

    Science.gov (United States)

    Petrie, Ryan J; Gavara, Núria; Chadwick, Richard S; Yamada, Kenneth M

    2012-04-30

    We search in this paper for context-specific modes of three-dimensional (3D) cell migration using imaging for phosphatidylinositol (3,4,5)-trisphosphate (PIP3) and active Rac1 and Cdc42 in primary fibroblasts migrating within different 3D environments. In 3D collagen, PIP3 and active Rac1 and Cdc42 were targeted to the leading edge, consistent with lamellipodia-based migration. In contrast, elongated cells migrating inside dermal explants and the cell-derived matrix (CDM) formed blunt, cylindrical protrusions, termed lobopodia, and Rac1, Cdc42, and PIP3 signaling was nonpolarized. Reducing RhoA, Rho-associated protein kinase (ROCK), or myosin II activity switched the cells to lamellipodia-based 3D migration. These modes of 3D migration were regulated by matrix physical properties. Specifically, experimentally modifying the elasticity of the CDM or collagen gels established that nonlinear elasticity supported lamellipodia-based migration, whereas linear elasticity switched cells to lobopodia-based migration. Thus, the relative polarization of intracellular signaling identifies two distinct modes of 3D cell migration governed intrinsically by RhoA, ROCK, and myosin II and extrinsically by the elastic behavior of the 3D extracellular matrix.

  18. FASN, ErbB2-mediated glycolysis is required for breast cancer cell migration.

    Science.gov (United States)

    Zhou, Lan; Jiang, Sufang; Fu, Qiang; Smith, Kelly; Tu, Kailing; Li, Hua; Zhao, Yuhua

    2016-05-01

    Both fatty acid synthase (FASN) and ErbB2 have been shown to promote breast cancer cell migration. However, the underlying molecular mechanism remains poorly understood and there is no reported evidence that directly links glycolysis to breast cancer cell migration. In this study, we investigated the role of FASN, ErbB2-mediated glycolysis in breast cancer cell migration. First, we compared lactate dehydrogenase A (LDHA) protein levels, glycolysis and cell migration between FASN, ErbB2-overexpressing SK-BR-3 cells and FASN, ErbB2-low-expressing MCF7 cells. Then, SK-BR-3 cells were treated with cerulenin (Cer), an inhibitor of FASN, and ErbB2, LDHA protein levels, glycolysis, and cell migration were detected. Next, we transiently transfected ErbB2 plasmid into MCF7 cells and detected FASN, LDHA protein levels, glycolysis and cell migration. Heregulin-β1 (HRG-β1) is an activator of ErbB2 and 2-deoxyglucose (2-DG) and oxamate (OX) are inhibitors of glycolysis. MCF7 cells were treated with HRG-β1 alone, HRG-β1 plus 2-DG, OX or cerulenin and glycolysis, and cell migration were measured. We found that FASN, ErbB2-high-expressing SK-BR-3 cells displayed higher levels of glycolysis and migration than FASN, ErbB2-low-expressing MCF7 cells. Inhibition of FASN by cerulenin impaired glycolysis and migration in SK-BR-3 cells. Transient overexpression of ErbB2 in MCF7 cells promotes glycolysis and migration. Moreover, 2-deoxyglucose (2-DG), oxamate (OX), or cerulenin partially reverses heregulin-β1 (HRG-β1)-induced glycolysis and migration in MCF7 cells. In conclusion, this study demonstrates that FASN, ErbB2-mediated glycolysis is required for breast cancer cell migration. These novel findings indicate that targeting FASN, ErbB2-mediated glycolysis may be a new approach to reverse breast cancer cell migration.

  19. Fibronectin Modulates Cell Adhesion and Signaling to Promote Single Cell Migration of Highly Invasive Oral Squamous Cell Carcinoma.

    Directory of Open Access Journals (Sweden)

    Grasieli de Oliveira Ramos

    Full Text Available Cell migration is regulated by adhesion to the extracellular matrix (ECM through integrins and activation of small RhoGTPases, such as RhoA and Rac1, resulting in changes to actomyosin organization. During invasion, epithelial-derived tumor cells switch from laminin-enriched basal membrane to collagen and fibronectin-enriched connective tissue. How this switch affects the tumor migration is still unclear. We tested the hypothesis that ECM dictates the invasiveness of Oral Squamous Cell Carcinoma (OSCC. We analyzed the migratory properties of two OSCC lines, a low invasive cell line with high e-cadherin levels (Linv/HE-cad or a highly invasive cell line with low e-cadherin levels (Hinv/LE-cad, plated on different ECM components. Compared to laminin, fibronectin induced non-directional collective migration and decreased RhoA activity in Linv/HE-cad OSCC. For Hinv/LE-cad OSCC, fibronectin increased Rac1 activity and induced smaller adhesions, resulting in a fast single cell migration in both 2D and 3D environments. Consistent with these observations, human OSCC biopsies exhibited similar changes in cell-ECM adhesion distribution at the invasive front of the tumor, where cells encounter fibronectin. Our results indicate that ECM composition might induce a switch from collective to single cell migration according to tumor invasiveness due to changes in cell-ECM adhesion and the resulting signaling pathways that alter actomyosin organization.

  20. Inhibition of Rho-Kinase Abrogates Migration of Human Transitional Cell Carcinoma Cells : Results of an in vitro Study

    NARCIS (Netherlands)

    vom Dorp, Frank; Sanders, Harald; Boergermann, Christof; Luemmen, Gerd; Ruebben, Herbert; Jakobs, Karl H.; Schmidt, Martina

    2011-01-01

    Introduction: Migration of cells involves a complex signaling network. The aim of the present study was to elucidate the impact of Rho-kinase (ROK) on G protein-coupled receptor-induced migration of human transitional cell carcinoma cells in an in vitro experimental setting. Materials and Methods: I

  1. Cell-surface proteoglycan in sea urchin primary mesenchyme cell migration

    Energy Technology Data Exchange (ETDEWEB)

    Lane, M.C.

    1989-01-01

    Early in the development of the sea urchin embryo, the primary mesenchyme cells (PMC) migrate along the basal lamina of the blastocoel. Migration is inhibited in L. pictus embryos cultured in sulfate-free seawater and in S. purpuratus embryos exposed to exogenous {beta}-D-xylosides. An in vitro assay was developed to test the migratory capacity of normal PMC on normal and treated blastocoelic matrix. Sulfate deprivation and exposure to exogenous xyloside render PMC nonmotile on either matrix. Materials removed from the surface of normal PMC by treatment with 1 M urea restored migratory ability to defective cells, whereas a similar preparation isolated from the surface of epithelial cells at the same stage did not. Migration also resumed when cells were removed from the xyloside or returned to normal seawater. The urea extract was partially purified and characterized by radiolabeling, gel electrophoresis, fluorography, ion exchange chromatography, and western blotting. The PMC synthesize a large chondroitin sulfate/dermatan sulfate proteoglycan that is present in an active fraction isolated by chromatography. Chondroitinase ABC digestion of live cells blocked migration reversibly, further supporting the identification of the chondroitin sulfate/dermatan sulfate proteoglycan as the active component in the urea extract. Much of the incorporated sulfate was distributed along the filopodia in {sup 35}SO{sub 4}-labelled PMC by autoradiography. The morphology of normal and treated S. purpuratus PMC was examined by scanning electron microscopy, and differences in spreading, particularly of the extensive filopodia present on the cells, was observed. A model for the role of the chondroitin sulfate/dermatan sulfate proteoglycan in cell detachment during migration is proposed.

  2. Overexpression of Rac1 in leukemia patients and its role in leukemia cell migration and growth

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jiying [State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020 (China); Rao, Qing, E-mail: raoqing@gmail.com [State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020 (China); Wang, Min; Wei, Hui; Xing, Haiyan; Liu, Hang; Wang, Yanzhong; Tang, Kejing; Peng, Leiwen; Tian, Zheng; Wang, Jianxiang [State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020 (China)

    2009-09-04

    Rac1 belongs to the Rho family that act as critical mediators of signaling pathways controlling cell migration and proliferation and contributes to the interactions of hematopoietic stem cells with their microenvironment. Alteration of Rac1 might result in unbalanced interactions and ultimately lead to leukemogenesis. In this study, we analyze the expression of Rac1 protein in leukemia patients and determine its role in the abnormal behaviours of leukemic cells. Rac1 protein is overexpressed in primary acute myeloid leukemia cells as compared to normal bone marrow mononuclear cells. siRNA-mediated silencing of Rac1 in leukemia cell lines induced inhibition of cell migration, proliferation, and colony formation. Additionally, blocking Rac1 activity by an inhibitor of Rac1-GTPase, NSC23766, suppressed cell migration and growth. We conclude that overexpression of Rac1 contributes to the accelerated migration and high proliferation potential of leukemia cells, which could be implicated in leukemia development and progression.

  3. Down-regulation of vimentin expression inhibits carcinoma cell migration and adhesion.

    Science.gov (United States)

    McInroy, Lorna; Määttä, Arto

    2007-08-17

    Vimentin is a type III Intermediate filament protein that is expressed frequently in epithelial carcinomas correlating with invasiveness and poor prognosis. We have analysed migration and adhesion to collagenous matrix of a panel of carcinoma cell lines. In vitro invasiveness was highest in vimentin-positive SW480 colon cancer and MDA-MB-231 breast cancer cells and the role of vimentin in these cell lines was investigated by RNA interference. Down-regulation of vimentin expression resulted in impaired migration in both scratch-wound experiments and in invasion assays through cell culture inserts coated with collagen gel. Compromised migration was observed in both cell lines, whereas cell attachment assays revealed impaired adhesion to fibrillar collagen in MDA-MB-231 cells while the adhesion of vimentin-ablated SW480 cells, that express both vimentin and keratin intermediate filaments was not affected. In conclusion, ablation of vimentin expression inhibits migration and invasion of colon and breast cancer cell lines.

  4. A Cellular Potts Model simulating cell migration on and in matrix environments

    NARCIS (Netherlands)

    Scianna, M.; Preziosi, L.; Wolf, K.A.

    2013-01-01

    Cell migration on and through extracellular matrix is fundamental in a wide variety of physiological and pathological phenomena, and is exploited in scaffold-based tissue engineering. Migration is regulated by a number of extracellular matrix- or cell-derived biophysical parameters, such as matrix f

  5. Coagulation Factor Xa inhibits cancer cell migration via Protease-activated receptor-1 activation

    NARCIS (Netherlands)

    Borensztajn, Keren; Bijlsma, Maarten F.; Reitsma, Pieter H.; Peppelenbosch, Maikel R.; Spek, C. Arnold

    2009-01-01

    Cell migration is critically important in (patho) physiological processes. The metastatic potential of cancer cells partly depends on activation of the coagulation cascade. The aim of the present study was to determine whether coagulation factor X (FXa) can regulate the migration and invasion of can

  6. Optogenetic toolkit reveals the role of Ca2+ sparklets in coordinated cell migration.

    Science.gov (United States)

    Kim, Jin Man; Lee, Minji; Kim, Nury; Heo, Won Do

    2016-05-24

    Cell migration is controlled by various Ca(2+) signals. Local Ca(2+) signals, in particular, have been identified as versatile modulators of cell migration because of their spatiotemporal diversity. However, little is known about how local Ca(2+) signals coordinate between the front and rear regions in directionally migrating cells. Here, we elucidate the spatial role of local Ca(2+) signals in directed cell migration through combinatorial application of an optogenetic toolkit. An optically guided cell migration approach revealed the existence of Ca(2+) sparklets mediated by L-type voltage-dependent Ca(2+) channels in the rear part of migrating cells. Notably, we found that this locally concentrated Ca(2+) influx acts as an essential transducer in establishing a global front-to-rear increasing Ca(2+) gradient. This asymmetrical Ca(2+) gradient is crucial for maintaining front-rear morphological polarity by restricting spontaneous lamellipodia formation in the rear part of migrating cells. Collectively, our findings demonstrate a clear link between local Ca(2+) sparklets and front-rear coordination during directed cell migration.

  7. Crossing barriers: the new dimension of 2D cell migration assays.

    NARCIS (Netherlands)

    Horssen, R. van; Hagen, T.L.M. ten

    2011-01-01

    In our body cells move in three dimensions, embedded in an extracellular matrix that varies in composition, density and stiffness, and this movement is fundamental to life. Next to 3D cell migration assays, representing these physiological circumstances, still we need 2D migrations assays to perform

  8. Dexamethasone Inhibits Tumor Necrosis Factor-α-stimulated Gastric Epithelial Cell Migration

    Directory of Open Access Journals (Sweden)

    Jiing-Chyuan Luo

    2009-10-01

    Conclusion: TNF-α plays a regulatory role in rat gastric epithelial cell migration and dexamethasone inhibited TNF-α-stimulated cell migration, which was associated with a decrease in COX-2 expression and PGE2 formation. [J Chin Med Assoc 2009;72(10:509–514

  9. Matrix metalloproteinase 13 mediates nitric oxide activation of endothelial cell migration

    Science.gov (United States)

    López-Rivera, Esther; Lizarbe, Tania R.; Martínez-Moreno, Mónica; López-Novoa, José Miguel; Rodríguez-Barbero, Alicia; Rodrigo, José; Fernández, Ana Patricia; Álvarez-Barrientos, Alberto; Lamas, Santiago; Zaragoza, Carlos

    2005-01-01

    To explore the mechanisms by which NO elicits endothelial cell (EC) migration we used murine and bovine aortic ECs in an in vitro wound-healing model. We found that exogenous or endogenous NO stimulated EC migration. Moreover, migration was significantly delayed in ECs derived from endothelial NO synthase-deficient mice compared with WT murine aortic EC. To assess the contribution of matrix metalloproteinase (MMP)-13 to NO-mediated EC migration, we used RNA interference to silence MMP-13 expression in ECs. Migration was delayed in cells in which MMP-13 was silenced. In untreated cells MMP-13 was localized to caveolae, forming a complex with caveolin-1. Stimulation with NO disrupted this complex and significantly increased extracellular MMP-13 abundance, leading to collagen breakdown. Our findings show that MMP-13 is an important effector of NO-activated endothelial migration. PMID:15728377

  10. Class 3 semaphorins induce F-actin reorganization in human dendritic cells: Role in cell migration.

    Science.gov (United States)

    Curreli, Sabrina; Wong, Bin Sheng; Latinovic, Olga; Konstantopoulos, Konstantinos; Stamatos, Nicholas M

    2016-12-01

    Class 3 semaphorins (Semas) are soluble proteins that are well recognized for their role in guiding axonal migration during neuronal development. In the immune system, Sema3A has been shown to influence murine dendritic cell (DC) migration by signaling through a neuropilin (NRP)-1/plexin-A1 coreceptor axis. Potential roles for class 3 Semas in human DCs have yet to be described. We tested the hypothesis that Sema3A, -3C, and -3F, each with a unique NRP-1 and/or NRP-2 binding specificity, influence human DC migration. In this report, we find that although NRP-1 and NRP-2 are expressed in human immature DCs (imDCs), NRP-2 expression increases as cells mature further, whereas expression of NRP-1 declines dramatically. Elevated levels of RNA encoding plexin-A1 and -A3 are present in both imDCs and mature DC (mDCs), supporting the relevance of Sema/NRP/plexin signaling pathways in these cells. Sema3A, -3C, and -3F bind to human DCs, with Sema3F binding predominantly through NRP-2. The binding of these Semas leads to reorganization of actin filaments at the plasma membrane and increased transwell migration in the absence or presence of chemokine CCL19. Microfluidic chamber assays failed to demonstrate consistent changes in speed of Sema3C-treated DCs, suggesting increased cell deformability as a possible explanation for enhanced transwell migration. Although monocytes express RNA encoding Sema3A, -3C, and -3F, only RNA encoding Sema3C increases robustly during DC differentiation. These data suggest that Sema3A, -3C, and -3F, likely with coreceptors NRP-1, NRP-2, and plexin-A1 and/or -A3, promote migration and possibly other activities of human DCs during innate and adaptive immune responses.

  11. Balancing Cell Migration with Matrix Degradation Enhances Gene Delivery to Cells Cultured Three-Dimensionally Within Hydrogels

    Science.gov (United States)

    Shepard, Jaclyn A.; Huang, Alyssa; Shikanova, Ariella; Shea, Lonnie D.

    2010-01-01

    In regenerative medicine, hydrogels are employed to fill defects and support the infiltration of cells that can ultimately regenerate tissue. Gene delivery within hydrogels targeting infiltrating cells has the potential to promote tissue formation, but the delivery efficiency of nonviral vectors within hydrogels is low hindering their applicability in tissue regeneration. To improve their functionality, we have conducted a mechanistic study to investigate the contribution of cell migration and matrix degradation on gene delivery. In this report, lipoplexes were entrapped within hydrogels based on poly(ethylene glycol) (PEG) crosslinked with peptides containing matrix metalloproteinase degradable sequences. The mesh size of these hydrogels is substantially less than the size of the entrapped lipoplexes, which can function to retain vectors. Cell migration and transfection were simultaneously measured within hydrogels with varying density of cell adhesion sites (Arg-Gly-Asp peptides) and solids content. Increasing RGD density increased expression levels up to 100-fold, while greater solids content sustained expression levels for 16 days. Increasing RGD density and decreasing solids content increased cell migration, which indicates expression levels increase with increased cell migration. Initially exposing cells to vector resulted in transient expression that declined after 2 days, verifying the requirement of migration to sustain expression. Transfected cells were predominantly located within the population of migrating cells for hydrogels that supported cell migration. Although the small mesh size retained at least 70% of the lipoplexes in the absence of cells after 32 days, the presence of cells decreased retention to 10% after 16 days. These results indicate that vectors retained within hydrogels contact migrating cells, and that persistent cell migration can maintain elevated expression levels. Thus matrix degradation and cell migration are fundamental design

  12. A novel role for Lh3 dependent ECM modifications during neural crest cell migration in zebrafish.

    Directory of Open Access Journals (Sweden)

    Santanu Banerjee

    Full Text Available During vertebrate development, trunk neural crest cells delaminate along the entire length of the dorsal neural tube and initially migrate as a non-segmented sheet. As they enter the somites, neural crest cells rearrange into spatially restricted segmental streams. Extracellular matrix components are likely to play critical roles in this transition from a sheet-like to a stream-like mode of migration, yet the extracellular matrix components and their modifying enzymes critical for this transition are largely unknown. Here, we identified the glycosyltransferase Lh3, known to modify extracellular matrix components, and its presumptive substrate Collagen18A1, to provide extrinsic signals critical for neural crest cells to transition from a sheet-like migration behavior to migrating as a segmental stream. Using live cell imaging we show that in lh3 null mutants, neural crest cells fail to transition from a sheet to a stream, and that they consequently enter the somites as multiple streams, or stall shortly after entering the somites. Moreover, we demonstrate that transgenic expression of lh3 in a small subset of somitic cells adjacent to where neural crest cells switch from sheet to stream migration restores segmental neural crest cell migration. Finally, we show that knockdown of the presumptive Lh3 substrate Collagen18A1 recapitulates the neural crest cell migration defects observed in lh3 mutants, consistent with the notion that Lh3 exerts its effect on neural crest cell migration by regulating post-translational modifications of Collagen18A1. Together these data suggest that Lh3-Collagen18A1 dependent ECM modifications regulate the transition of trunk neural crest cells from a non-segmental sheet like migration mode to a segmental stream migration mode.

  13. A novel role for Lh3 dependent ECM modifications during neural crest cell migration in zebrafish.

    Science.gov (United States)

    Banerjee, Santanu; Isaacman-Beck, Jesse; Schneider, Valerie A; Granato, Michael

    2013-01-01

    During vertebrate development, trunk neural crest cells delaminate along the entire length of the dorsal neural tube and initially migrate as a non-segmented sheet. As they enter the somites, neural crest cells rearrange into spatially restricted segmental streams. Extracellular matrix components are likely to play critical roles in this transition from a sheet-like to a stream-like mode of migration, yet the extracellular matrix components and their modifying enzymes critical for this transition are largely unknown. Here, we identified the glycosyltransferase Lh3, known to modify extracellular matrix components, and its presumptive substrate Collagen18A1, to provide extrinsic signals critical for neural crest cells to transition from a sheet-like migration behavior to migrating as a segmental stream. Using live cell imaging we show that in lh3 null mutants, neural crest cells fail to transition from a sheet to a stream, and that they consequently enter the somites as multiple streams, or stall shortly after entering the somites. Moreover, we demonstrate that transgenic expression of lh3 in a small subset of somitic cells adjacent to where neural crest cells switch from sheet to stream migration restores segmental neural crest cell migration. Finally, we show that knockdown of the presumptive Lh3 substrate Collagen18A1 recapitulates the neural crest cell migration defects observed in lh3 mutants, consistent with the notion that Lh3 exerts its effect on neural crest cell migration by regulating post-translational modifications of Collagen18A1. Together these data suggest that Lh3-Collagen18A1 dependent ECM modifications regulate the transition of trunk neural crest cells from a non-segmental sheet like migration mode to a segmental stream migration mode.

  14. A minimal model for spontaneous cell polarization and edge activity in oscillating, rotating and migrating cells

    CERN Document Server

    Raynaud, Franck; Gabella, Chiara; Bornert, Alicia; Sbalzarini, Ivo F; Meister, Jean-Jacques; Verkhovsky, Alexander B

    2016-01-01

    How the cells break symmetry and organize their edge activity to move directionally is a fun- damental question in cell biology. Physical models of cell motility commonly rely on gradients of regulatory factors and/or feedback from the motion itself to describe polarization of edge activity. Theses approaches, however, fail to explain cell behavior prior to the onset of polarization. Our analysis using the model system of polarizing and moving fish epidermal keratocytes suggests a novel and simple principle of self-organization of cell activity in which local cell-edge dynamics depends on the distance from the cell center, but not on the orientation with respect to the front-back axis. We validate this principle with a stochastic model that faithfully reproduces a range of cell-migration behaviors. Our findings indicate that spontaneous polarization, persistent motion, and cell shape are emergent properties of the local cell-edge dynamics controlled by the distance from the cell center.

  15. Myosin-II-Mediated Directional Migration of Dictyostelium Cells in Response to Cyclic Stretching of Substratum

    Science.gov (United States)

    Iwadate, Yoshiaki; Okimura, Chika; Sato, Katsuya; Nakashima, Yuta; Tsujioka, Masatsune; Minami, Kazuyuki

    2013-01-01

    Living cells are constantly subjected to various mechanical stimulations, such as shear flow, osmotic pressure, and hardness of substratum. They must sense the mechanical aspects of their environment and respond appropriately for proper cell function. Cells adhering to substrata must receive and respond to mechanical stimuli from the substrata to decide their shape and/or migrating direction. In response to cyclic stretching of the elastic substratum, intracellular stress fibers in fibroblasts and endothelial, osteosarcoma, and smooth muscle cells are rearranged perpendicular to the stretching direction, and the shape of those cells becomes extended in this new direction. In the case of migrating Dictyostelium cells, cyclic stretching regulates the direction of migration, and not the shape, of the cell. The cells migrate in a direction perpendicular to that of the stretching. However, the molecular mechanisms that induce the directional migration remain unknown. Here, using a microstretching device, we recorded green fluorescent protein (GFP)-myosin-II dynamics in Dictyostelium cells on an elastic substratum under cyclic stretching. Repeated stretching induced myosin II localization equally on both stretching sides in the cells. Although myosin-II-null cells migrated randomly, myosin-II-null cells expressing a variant of myosin II that cannot hydrolyze ATP migrated perpendicular to the stretching. These results indicate that Dictyostelium cells accumulate myosin II at the portion of the cell where a large strain is received and migrate in a direction other than that of the portion where myosin II accumulated. This polarity generation for migration does not require the contraction of actomyosin. PMID:23442953

  16. A modeling approach to study the effect of cell polarization on keratinocyte migration.

    Directory of Open Access Journals (Sweden)

    Matthias Jörg Fuhr

    Full Text Available The skin forms an efficient barrier against the environment, and rapid cutaneous wound healing after injury is therefore essential. Healing of the uppermost layer of the skin, the epidermis, involves collective migration of keratinocytes, which requires coordinated polarization of the cells. To study this process, we developed a model that allows analysis of live-cell images of migrating keratinocytes in culture based on a small number of parameters, including the radius of the cells, their mass and their polarization. This computational approach allowed the analysis of cell migration at the front of the wound and a reliable identification and quantification of the impaired polarization and migration of keratinocytes from mice lacking fibroblast growth factors 1 and 2--an established model of impaired healing. Therefore, our modeling approach is suitable for large-scale analysis of migration phenotypes of cells with specific genetic defects or upon treatment with different pharmacological agents.

  17. The satellite cell in male and female, developing and adult mouse muscle: distinct stem cells for growth and regeneration.

    Directory of Open Access Journals (Sweden)

    Alice Neal

    Full Text Available Satellite cells are myogenic cells found between the basal lamina and the sarcolemma of the muscle fibre. Satellite cells are the source of new myofibres; as such, satellite cell transplantation holds promise as a treatment for muscular dystrophies. We have investigated age and sex differences between mouse satellite cells in vitro and assessed the importance of these factors as mediators of donor cell engraftment in an in vivo model of satellite cell transplantation. We found that satellite cell numbers are increased in growing compared to adult and in male compared to female adult mice. We saw no difference in the expression of the myogenic regulatory factors between male and female mice, but distinct profiles were observed according to developmental stage. We show that, in contrast to adult mice, the majority of satellite cells from two week old mice are proliferating to facilitate myofibre growth; however a small proportion of these cells are quiescent and not contributing to this growth programme. Despite observed changes in satellite cell populations, there is no difference in engraftment efficiency either between satellite cells derived from adult or pre-weaned donor mice, male or female donor cells, or between male and female host muscle environments. We suggest there exist two distinct satellite cell populations: one for muscle growth and maintenance and one for muscle regeneration.

  18. Neurotensin is a Versatile Modulator of In Vitro Human Pancreatic Ductal Adenocarcinoma Cell (PDAC Migration

    Directory of Open Access Journals (Sweden)

    Tatjana Mijatovic

    2007-01-01

    Full Text Available Background: While the neurotensin (NT roles in pancreatic cancer growth are well documented, its effects on pancreatic cancer cell migration have not been described. Methods: The NT-induced effects on the migration process of human pancreatic ductal adenocarcinoma cells (PDACs were characterized by means of various assays including computer-assisted video-microscopy, fluorescence microscopy, ELISA-based, small GTPase pull-down and phosphorylation assays. Results: The NT-induced modifications on in vitro PDACs migration largely depended on the extra-cellular matrix environment and cell propensity to migrate collectively or individually. While NT significantly reduced the level of migration of collectively migrating PDACs on vitronectin, it significantly increased the level of individually migrating PDACs. These effects were mainly mediated through the sortilin/NTR3 receptor. Neurotensin both induced altered expression of αV and β5 integrin subunits in PDACs cultured on vitronectin resulting in modified adhesion abilities, and caused modifications to the organization of the actin cytoskeleton through the NT-mediated activation of small Rho GTPases. While the NT effects on individually migrating PDACs were mediated at least through the EGFR/ERK signaling pathways, those on collectively migrating PDACs appeared highly dependent on the PI 3-kinase pathway. Conclusion: This study strongly suggests the involvement of neurotensin in the modulation of human PDAC migration.

  19. Electrical signals polarize neuronal organelles, direct neuron migration, and orient cell division.

    Science.gov (United States)

    Yao, Li; McCaig, Colin D; Zhao, Min

    2009-09-01

    During early brain development, the axis of division of neuronal precursor cells is regulated tightly and can determine whether neurons remain in the germinal layers or migrate away. Directed neuronal migration depends on the establishment of cell polarity, and cells are polarized dynamically in response to extracellular signals. Endogenous electric fields (EFs) orient cell division and direct migration of a variety of cell types. Here, we show that cell division of cultured hippocampal cells (neuron-like cells and glial-like cells) is oriented strikingly by an applied EF, which also directs neuronal migration. Directed migration involves polarization of the leading neurite, of the microtubule-associated protein MAP-2 and of the Golgi apparatus and the centrosome, all of which reposition asymmetrically to face the cathode. Pharmacological inhibition of Rho-associated coiled-coil forming protein kinases (ROCK) and phosphoinositide 3-kinase decreased, leading neurite orientation and Golgi polarization in the neurons in response to an EF and in parallel decreased the directedness of EF-guided neuronal migration. This work demonstrates that the axis of hippocampal cell division, the establishment of neuronal polarity, the polarization of intracellular structures, and the direction of neuronal migration are all regulated by an extracellular electrical cue.

  20. Analysis of Histone Deacetylase-Dependent Effects on Cell Migration Using the Stripe Assay.

    Science.gov (United States)

    Mertsch, Sonja; Thanos, Solon

    2017-01-01

    For normal embryonic development/morphogenesis, cell migration and homing are well-orchestrated and important events requiring specific cellular mechanisms. In diseases such as cancer deregulated cell migration represents a major problem. Therefore, numerous efforts are under way to understand the molecular mechanisms of tumor cell migration and to generate more efficient tumor therapies. Cell migration assays are one of the most commonly used functional assays. The wound-healing assay or the Boyden chamber assay are variations of these assays. Nearly all of them are two-dimensional assays and the cells can only migrate on one substrate at a time. This is in contrast to the in vivo situation where the cells are faced simultaneously with different surfaces and interact with different cell types. To approach this in vivo situation we used a modified version of the stripe assay designed by Bonhoeffer and colleagues to examine mechanisms of axonal guidance. The design of this assay allows cells to decide between two different substrates offered at the same time. Utilizing alternating neuronal substrates for migration analyses we can partially mimic the complex in vivo situation for brain tumor cells. Here we describe the detailed protocol to perform a modified version of the stripe assay in order to observe substrate-dependent migration effects in vitro, to analyze the effect of Rho-dependent kinases (ROCKS), of histone deacetylases (HDACs) and of other molecules on glioma cells.

  1. Common mechanisms linking connexin43 to neural progenitor cell migration and glioma invasion.

    Science.gov (United States)

    Naus, Christian C; Aftab, Qurratulain; Sin, Wun Chey

    2016-02-01

    Cell migration is critical for cell differentiation, tissue formation and organ development. Several mechanisms come to play in the process of cell migration, orchestrating changes in cell polarity, adhesion, process extension and motility. Recent findings have shown that gap junctions, and specifically connexin43 (Cx43), can play a significant role in these processes, impacting adhesion and cytoskeletal rearrangements. Thus Cx43 within a cell regulates its motility and migration via intracellular signaling. Furthermore, Cx43 in the host cells can impact the degree of cellular migration through that tissue. Similarities in these connexin-based processes account for both neural progenitor migration in the developing brain, and for glioma cell invasion in the mature brain. In both cases, Cx43 in the tissue ("soil") in which cells ("seeds") exist facilitates their migration and, for glioma cells, tissue invasion. Cx43 mediates these effects through channel- and non-channel-dependent mechanisms which have similarities in both paradigms of cell migration. This provides insight into developmental processes and pathological situations, as well as possible therapeutic approaches regarding specific functional domains of gap junction proteins.

  2. Cortactin affects cell migration by regulating intercellular adhesion and cell spreading

    NARCIS (Netherlands)

    van Rossum, AGSH; Moolenaar, WH; Schuuring, E

    2006-01-01

    Cortactin is an F-actin binding protein that stabilizes F-actin networks and promotes actin polymerization by activating the Arp2/3 complex. Overexpression of cortactin, as observed in several human cancers, stimulates cell migration, invasion, and experimental metastasis; however, the underlying

  3. Lipid raft association restricts CD44-ezrin interaction and promotion of breast cancer cell migration.

    LENUS (Irish Health Repository)

    Donatello, Simona

    2012-12-01

    Cancer cell migration is an early event in metastasis, the main cause of breast cancer-related deaths. Cholesterol-enriched membrane domains called lipid rafts influence the function of many molecules, including the raft-associated protein CD44. We describe a novel mechanism whereby rafts regulate interactions between CD44 and its binding partner ezrin in migrating breast cancer cells. Specifically, in nonmigrating cells, CD44 and ezrin localized to different membranous compartments: CD44 predominantly in rafts, and ezrin in nonraft compartments. After the induction of migration (either nonspecific or CD44-driven), CD44 affiliation with lipid rafts was decreased. This was accompanied by increased coprecipitation of CD44 and active (threonine-phosphorylated) ezrin-radixin-moesin (ERM) proteins in nonraft compartments and increased colocalization of CD44 with the nonraft protein, transferrin receptor. Pharmacological raft disruption using methyl-β-cyclodextrin also increased CD44-ezrin coprecipitation and colocalization, further suggesting that CD44 interacts with ezrin outside rafts during migration. Conversely, promoting CD44 retention inside lipid rafts by pharmacological inhibition of depalmitoylation virtually abolished CD44-ezrin interactions. However, transient single or double knockdown of flotillin-1 or caveolin-1 was not sufficient to increase cell migration over a short time course, suggesting complex crosstalk mechanisms. We propose a new model for CD44-dependent breast cancer cell migration, where CD44 must relocalize outside lipid rafts to drive cell migration. This could have implications for rafts as pharmacological targets to down-regulate cancer cell migration.

  4. A parallel and quantitative cell migration assay using a novel multi-well-based device.

    Science.gov (United States)

    Quan, Qianghua; Zhang, Shuwen; Wang, Xudong; Ouyang, Qi; Wang, Yugang; Yang, Gen; Luo, Chunxiong

    2016-12-01

    Cell migration assays for different chemical environments are important for both scientists and clinicians searching for new therapeutics. In this study, we developed a multi-well-based microfluidic chip that has multiple units for different conditions. In each unit, cells can be patterned and then released to observe their migration. Automatic image analysis and model-based data processing were developed to describe the integrated cell migration assay precisely and quickly. As a demonstration, the migration behaviors of two types of cells in eight chemical conditions were studied. The results showed that supplementation with transforming growth factor-β(TGF-β) significantly promoted the migration of MCF-7 and MCF-10 A cells compared to several growth factors, such as Epidermal Growth Factor(EGF) and basic fibroblast growth factor(bFGF), as well as a control sample. Cells can migrate particularly fast with two or more mixed supplementary factors, such as TGF-β + bFGF + EGF, which indicated a synergy effect. Thus, this chip could be used to quantitatively observe cancer cell migration and demonstrated great potential for use in quantitative migration studies and chemical screening.

  5. Cell-alignment patterns in the collective migration of cells with polarized adhesion

    Science.gov (United States)

    Matsushita, Katsuyoshi

    2017-03-01

    Dictyostelium discoideum (Dd) utilizes inhomogeneities in the distribution of cell-cell adhesion molecules on cell membranes for collective cell migration. A simple example of an inhomogeneity is a front-side (leading-edge) polarization in the distribution at the early streaming stage. Experiments have shown that the polarized cell-cell adhesion induces side-by-side contact between cells [Beug et al., Nature (London) 274, 445 (1978), 10.1038/274445a0]. This result is counterintuitive, as one would expect cells to align front to front in contact with each other on the basis of front-side polarization. In this work, we theoretically examine whether front-side polarization induces side-by-side contact in collective cell migration. We construct a model for expressing cells with this polarization based on the two-dimensional cellular Potts model. By a numerical simulation with this model, we find cell-cell alignment wherein cells form lateral arrays with side-by-side contacts as observed in the experiments.

  6. Miniature Dielectric Barrier Discharge Nonthermal Plasma Induces Apoptosis in Lung Cancer Cells and Inhibits Cell Migration

    Science.gov (United States)

    Eisenmann, Kathryn M.

    2017-01-01

    Traditional cancer treatments like radiotherapy and chemotherapy have drawbacks and are not selective for killing only cancer cells. Nonthermal atmospheric pressure plasmas with dielectric barrier discharge (DBD) can be applied to living cells and tissues and have emerged as novel tools for localized cancer therapy. The purpose of this study was to investigate the different effects caused by miniature DBD (mDBD) plasma to A549 lung cancer cells. In this study, A549 lung cancer cells cultured in 12 well plates were treated with mDBD plasma for specified treatment times to assess the changes in the size of the area of cell detachment, the viability of attached or detached cells, and cell migration. Furthermore, we investigated an innovative mDBD plasma-based therapy for localized treatment of lung cancer cells through apoptotic induction. Our results indicate that plasma treatment for 120 sec causes apoptotic cell death in 35.8% of cells, while mDBD plasma treatment for 60 sec, 30 sec, or 15 sec causes apoptotic cell death in 20.5%, 14.1%, and 6.3% of the cell population, respectively. Additionally, we observed reduced A549 cell migration in response to mDBD plasma treatment. Thus, mDBD plasma system can be a viable platform for localized lung cancer therapy. PMID:28243603

  7. Cdc42 is not essential for filopodium formation, directed migration, cell polarization, and mitosis in fibroblastoid cells

    DEFF Research Database (Denmark)

    Czuchra, Aleksandra; Wu, Xunwei; Meyer, Hannelore

    2005-01-01

    Cdc42 is a small GTPase involved in the regulation of the cytoskeleton and cell polarity. To test whether Cdc42 has an essential role in the formation of filopodia or directed cell migration, we generated Cdc42-deficient fibroblastoid cells by conditional gene inactivation. We report here that loss...... of Cdc42 did not affect filopodium or lamellipodium formation and had no significant influence on the speed of directed migration nor on mitosis. Cdc42-deficient cells displayed a more elongated cell shape and had a reduced area. Furthermore, directionality during migration and reorientation of the Golgi...... apparatus into the direction of migration was decreased. However, expression of dominant negative Cdc42 in Cdc42-null cells resulted in strongly reduced directed migration, severely reduced single cell directionality, and complete loss of Golgi polarization and of directionality of protrusion formation...

  8. Effect of S1P5 on proliferation and migration of human esophageal cancer cells

    OpenAIRE

    Hu, Wei-Min; Li, Li; Jing, Bao-Qian; Zhao, Yong-Sheng; Wang, Chao-Li; Feng, Li; Xie, Yong-En

    2010-01-01

    AIM: To investigate the sphingosine 1-phosphate (S1P) receptor expression profile in human esophageal cancer cells and the effects of S1P5 on proliferation and migration of human esophageal cancer cells.

  9. Genetic engineering of human NK cells to express CXCR2 improves migration to renal cell carcinoma.

    Science.gov (United States)

    Kremer, Veronika; Ligtenberg, Maarten; Zendehdel, Rosa; Seitz, Christina; Duivenvoorden, Annet; Wennerberg, Erik; Colón, Eugenia; Scherman-Plogell, Ann-Helén; Lundqvist, Andreas

    2017-09-19

    Adoptive natural killer (NK) cell transfer is being increasingly used as cancer treatment. However, clinical responses have so far been limited to patients with hematological malignancies. A potential limiting factor in patients with solid tumors is defective homing of the infused NK cells to the tumor site. Chemokines regulate the migration of leukocytes expressing corresponding chemokine receptors. Various solid tumors, including renal cell carcinoma (RCC), readily secrete ligands for the chemokine receptor CXCR2. We hypothesize that infusion of NK cells expressing high levels of the CXCR2 chemokine receptor will result in increased influx of the transferred NK cells into tumors, and improved clinical outcome in patients with cancer. Blood and tumor biopsies from 14 primary RCC patients were assessed by flow cytometry and chemokine analysis. Primary NK cells were transduced with human CXCR2 using a retroviral system. CXCR2 receptor functionality was determined by Calcium flux and NK cell migration was evaluated in transwell assays. We detected higher concentrations of CXCR2 ligands in tumors compared with plasma of RCC patients. In addition, CXCL5 levels correlated with the intratumoral infiltration of CXCR2-positive NK cells. However, tumor-infiltrating NK cells from RCC patients expressed lower CXCR2 compared with peripheral blood NK cells. Moreover, healthy donor NK cells rapidly lost their CXCR2 expression upon in vitro culture and expansion. Genetic modification of human primary NK cells to re-express CXCR2 improved their ability to specifically migrate along a chemokine gradient of recombinant CXCR2 ligands or RCC tumor supernatants compared with controls. The enhanced trafficking resulted in increased killing of target cells. In addition, while their functionality remained unchanged compared with control NK cells, CXCR2-transduced NK cells obtained increased adhesion properties and formed more conjugates with target cells. To increase the success of NK

  10. Salinomycin treatment reduces metastatic tumor burden by hampering cancer cell migration

    OpenAIRE

    Kopp, Florian; Hermawan, Adam; Oak, Prajakta Shirish; Herrmann, Annika; Wagner, Ernst; Roidl, Andreas

    2014-01-01

    Background: Tumor spreading is the major threat for cancer patients. The recently published anti-cancer drug salinomycin raised hope for an improved treatment by targeting therapy-refractory cancer stem cells. However, an unambiguous role of salinomycin against cancer cell migration and metastasis formation remains elusive. Findings: We report that salinomycin effectively inhibits cancer cell migration in a variety of cancer types as determined by Boyden chamber assays. Additionally, cells we...

  11. Immature human dendritic cells enhance their migration through KCa3.1 channel activation.

    Science.gov (United States)

    Crottès, David; Félix, Romain; Meley, Daniel; Chadet, Stéphanie; Herr, Florence; Audiger, Cindy; Soriani, Olivier; Vandier, Christophe; Roger, Sébastien; Angoulvant, Denis; Velge-Roussel, Florence

    2016-04-01

    Migration capacity is essential for dendritic cells (DCs) to present antigen to T cells for the induction of immune response. The DC migration is supposed to be a calcium-dependent process, while not fully understood. Here, we report a role of the KCa3.1/IK1/SK4 channels in the migration capacity of both immature (iDC) and mature (mDC) human CD14(+)-derived DCs. KCa3.1 channels were shown to control the membrane potential of human DC and the Ca(2+) entry, which is directly related to migration capacities. The expression of migration marker such as CCR5 and CCR7 was modified in both types of DCs by TRAM-34 (100nM). But, only the migration of iDC was decreased by use of both TRAM-34 and KCa3.1 siRNA. Confocal analyses showed a close localization of CCR5 with KCa3.1 in the steady state of iDC. Finally, the implication of KCa3.1 seems to be limited to the migration capacities as T cell activation of DCs appeared unchanged. Altogether, these results demonstrated that KCa3.1 channels have a pro-migratory effect on iDC migration. Our findings suggest that KCa3.1 in human iDC play a major role in their migration and constitute an attractive target for the cell therapy optimization.

  12. Hypoxia promotes Rab5 activation, leading to tumor cell migration, invasion and metastasis.

    Science.gov (United States)

    Silva, Patricio; Mendoza, Pablo; Rivas, Solange; Díaz, Jorge; Moraga, Carolina; Quest, Andrew F G; Torres, Vicente A

    2016-05-17

    Hypoxia, a common condition of the tumor microenvironment, is associated with poor patient prognosis, tumor cell migration, invasion and metastasis. Recent evidence suggests that hypoxia alters endosome dynamics in tumor cells, leading to augmented cell proliferation and migration and this is particularly relevant, because endosomal components have been shown to be deregulated in cancer. The early endosome protein Rab5 is a small GTPase that promotes integrin trafficking, focal adhesion turnover, Rac1 activation, tumor cell migration and invasion. However, the role of Rab5 and downstream events in hypoxia remain unknown. Here, we identify Rab5 as a critical player in hypoxia-driven tumor cell migration, invasion and metastasis. Exposure of A549 human lung carcinoma, ZR-75, MDA-MB-231 and MCF-7 human breast cancer and B16-F10 mouse melanoma cells to hypoxia increased Rab5 activation, followed by its re-localization to the leading edge and association with focal adhesions. Importantly, Rab5 was required for hypoxia-driven cell migration, FAK phosphorylation and Rac1 activation, as shown by shRNA-targeting and transfection assays with Rab5 mutants. Intriguingly, the effect of hypoxia on both Rab5 activity and migration was substantially higher in metastatic B16-F10 cells than in poorly invasive B16-F0 cells. Furthermore, exogenous expression of Rab5 in B16-F0 cells predisposed to hypoxia-induced migration, whereas expression of the inactive mutant Rab5/S34N prevented the migration of B16-F10 cells induced by hypoxia. Finally, using an in vivo syngenic C57BL/6 mouse model, Rab5 expression was shown to be required for hypoxia-induced metastasis. In summary, these findings identify Rab5 as a key mediator of hypoxia-induced tumor cell migration, invasion and metastasis.

  13. Impact of Mesenchymal Stem Cell secreted PAI-1 on colon cancer cell migration and proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, Niamh M. [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland); Joyce, Myles R. [Department of Colorectal Surgery, University College Hospital, Galway (Ireland); Murphy, J. Mary; Barry, Frank P.; O’Brien, Timothy [Regenerative Medicine Institute, National University of Ireland, Galway (Ireland); Kerin, Michael J. [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland); Dwyer, Roisin M., E-mail: roisin.dwyer@nuigalway.ie [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland)

    2013-06-14

    Highlights: •MSCs were directly co-cultured with colorectal cancer (CRC) cells on 3D scaffolds. •MSCs influence CRC protein/gene expression, proliferation and migration. •We report a significant functional role of MSC-secreted PAI-1 in colon cancer. -- Abstract: Mesenchymal Stem Cells are known to engraft and integrate into the architecture of colorectal tumours, with little known regarding their fate following engraftment. This study aimed to investigate mediators of Mesenchymal Stem Cell (MSC) and colon cancer cell (CCC) interactions. Mesenchymal Stem Cells and colon cancer cells (HT29 and HCT-116) were cultured individually or in co-culture on 3-dimensional scaffolds. Conditioned media containing all secreted factors was harvested at day 1, 3 and 7. Chemokine secretion and expression were analyzed by Chemi-array, ELISA (Macrophage migration inhibitory factor (MIF), plasminogen activator inhibitor type 1 (PAI-1)) and RQ-PCR. Colon cancer cell migration and proliferation in response to recombinant PAI-1, MSCs and MSCs + antibody to PAI-1 was analyzed using Transwell inserts and an MTS proliferation assay respectively. Chemi-array revealed secretion of a wide range of factors by each cell population, including PAI-1and MIF. ELISA analysis revealed Mesenchymal Stem Cells to secrete the highest levels of PAI-1 (MSC mean 10.6 ng/mL, CCC mean 1.01 ng/mL), while colon cancer cells were the principal source of MIF. MSC-secreted PAI-1 stimulated significant migration of both CCC lines, with an antibody to the chemokine shown to block this effect (67–88% blocking,). A cell-line dependant effect on CCC proliferation was shown for Mesenchymal Stem Cell-secreted PAI-1 with HCT-116 cells showing decreased proliferation at all concentrations, and HT29 cells showing increased proliferation in the presence of higher PAI-1 levels. This is the first study to identify PAI-1 as an important mediator of Mesenchymal Stem Cell/colon cancer cell interactions and highlights the

  14. RBP-J (Rbpsuh) is essential to maintain muscle progenitor cells and to generate satellite cells

    OpenAIRE

    Vasyutina, Elena; Lenhard, Diana C.; Wende, Hagen; Erdmann, Bettina; Epstein, Jonathan A.; Birchmeier, Carmen

    2007-01-01

    In the developing muscle, a pool of myogenic progenitor cells is formed and maintained. These resident progenitors provide a source of cells for muscle growth in development and generate satellite cells in the perinatal period. By the use of conditional mutagenesis in mice, we demonstrate here that the major mediator of Notch signaling, the transcription factor RBP-J, is essential to maintain this pool of progenitor cells in an undifferentiated state. In the absence of RBP-J, these cells unde...

  15. A quorum-sensing factor in vegetative Dictyostelium discoideum cells revealed by quantitative migration analysis.

    Directory of Open Access Journals (Sweden)

    Laurent Golé

    Full Text Available BACKGROUND: Many cells communicate through the production of diffusible signaling molecules that accumulate and once a critical concentration has been reached, can activate or repress a number of target genes in a process termed quorum sensing (QS. In the social amoeba Dictyostelium discoideum, QS plays an important role during development. However little is known about its effect on cell migration especially in the growth phase. METHODS AND FINDINGS: To investigate the role of cell density on cell migration in the growth phase, we use multisite timelapse microscopy and automated cell tracking. This analysis reveals a high heterogeneity within a given cell population, and the necessity to use large data sets to draw reliable conclusions on cell motion. In average, motion is persistent for short periods of time (t ≤ 5 min, but normal diffusive behavior is recovered over longer time periods. The persistence times are positively correlated with the migrated distances. Interestingly, the migrated distance decreases as well with cell density. The adaptation of cell migration to cell density highlights the role of a secreted quorum sensing factor (QSF on cell migration. Using a simple model describing the balance between the rate of QSF generation and the rate of QSF dilution, we were able to gather all experimental results into a single master curve, showing a sharp cell transition between high and low motile behaviors with increasing QSF. CONCLUSION: This study unambiguously demonstrates the central role played by QSF on amoeboid motion in the growth phase.

  16. Envisioning migration: mathematics in both experimental analysis and modeling of cell behavior.

    Science.gov (United States)

    Zhang, Elizabeth R; Wu, Lani F; Altschuler, Steven J

    2013-10-01

    The complex nature of cell migration highlights the power and challenges of applying mathematics to biological studies. Mathematics may be used to create model equations that recapitulate migration, which can predict phenomena not easily uncovered by experiments or intuition alone. Alternatively, mathematics may be applied to interpreting complex data sets with better resolution--potentially empowering scientists to discern subtle patterns amid the noise and heterogeneity typical of migrating cells. Iteration between these two methods is necessary in order to reveal connections within the cell migration signaling network, as well as to understand the behavior that arises from those connections. Here, we review recent quantitative analysis and mathematical modeling approaches to the cell migration problem. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Electric Signals Regulate the Directional Migration of Oligodendrocyte Progenitor Cells (OPCs) via β1 Integrin.

    Science.gov (United States)

    Zhu, Bangfu; Nicholls, Matthew; Gu, Yu; Zhang, Gaofeng; Zhao, Chao; Franklin, Robin J M; Song, Bing

    2016-11-22

    The guided migration of neural cells is essential for repair in the central nervous system (CNS). Oligodendrocyte progenitor cells (OPCs) will normally migrate towards an injury site to re-sheath demyelinated axons; however the mechanisms underlying this process are not well understood. Endogenous electric fields (EFs) are known to influence cell migration in vivo, and have been utilised in this study to direct the migration of OPCs isolated from neonatal Sprague-Dawley rats. The OPCs were exposed to physiological levels of electrical stimulation, and displayed a marked electrotactic response that was dependent on β1 integrin, one of the key subunits of integrin receptors. We also observed that F-actin, an important component of the cytoskeleton, was re-distributed towards the leading edge of the migrating cells, and that this asymmetric rearrangement was associated with β1 integrin function.

  18. Dynamic tensile forces drive collective cell migration through three-dimensional extracellular matrices

    Science.gov (United States)

    Gjorevski, Nikolce; S. Piotrowski, Alexandra; Varner, Victor D.; Nelson, Celeste M.

    2015-01-01

    Collective cell migration drives tissue remodeling during development, wound repair, and metastatic invasion. The physical mechanisms by which cells move cohesively through dense three-dimensional (3D) extracellular matrix (ECM) remain incompletely understood. Here, we show directly that migration of multicellular cohorts through collagenous matrices occurs via a dynamic pulling mechanism, the nature of which had only been inferred previously in 3D. Tensile forces increase at the invasive front of cohorts, serving a physical, propelling role as well as a regulatory one by conditioning the cells and matrix for further extension. These forces elicit mechanosensitive signaling within the leading edge and align the ECM, creating microtracks conducive to further migration. Moreover, cell movements are highly correlated and in phase with ECM deformations. Migrating cohorts use spatially localized, long-range forces and consequent matrix alignment to navigate through the ECM. These results suggest biophysical forces are critical for 3D collective migration. PMID:26165921

  19. RLIM interacts with Smurf2 and promotes TGF-{beta} induced U2OS cell migration

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yongsheng [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433 (China); State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084 (China); Yang, Yang; Gao, Rui; Yang, Xianmei [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433 (China); Yan, Xiaohua [State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084 (China); Wang, Chenji; Jiang, Sirui [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433 (China); Yu, Long, E-mail: longyu@fudan.edu.cn [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433 (China)

    2011-10-14

    Highlights: {yields} RLIM directly binds to Smurf2. {yields} RLIM enhances TGF-{beta} responsiveness in U2OS cells. {yields} RLIM promotes TGF-{beta} driven migration of osteosarcoma U2OS cells. -- Abstract: TGF-{beta} (transforming growth factor-{beta}), a pleiotropic cytokine that regulates diverse cellular processes, has been suggested to play critical roles in cell proliferation, migration, and carcinogenesis. Here we found a novel E3 ubiquitin ligase RLIM which can directly bind to Smurf2, enhancing TGF-{beta} responsiveness in osteosarcoma U2OS cells. We constructed a U2OS cell line stably over-expressing RLIM and demonstrated that RLIM promoted TGF-{beta}-driven migration of U2OS cells as tested by wound healing assay. Our results indicated that RLIM is an important positive regulator in TGF-{beta} signaling pathway and cell migration.

  20. How do cells produce and regulate the driving force in the process of migration?

    Science.gov (United States)

    Zhong, Y.; Ji, B.

    2014-06-01

    Cell migration behaviors have been studied from various aspects and at different length scales (molecular, subcellular and cellular scales), however, the mechanisms of how cell produces and controls the driving force for its migration have not been fully understood. Here for the first time we draw a more unified picture of driving force production that integrates the mechanisms from molecular to subcellular and cellular levels to show how cell produces and regulates the driving force and thus control its motility. We suggest that although the external mechanical and chemical factors can influence cell migration, the cell is able to actively control and regulate its driving force for its motility through controlling the stability of cell adhesion via actively regulating its spreading shape. To demonstrate this picture of regulation of the driving force, a FEM-based simulation framework is developed by modeling the dynamics of adhesion at cell front, de-adhesion at cell rear, and forward motion of cell body under cell traction force for different cell shape. The migration of keratocyte and fibroblast cells is simulated for different matrix rigidity and rigidity gradient. We show that the cell migration speed biphasically depends on the matrix rigidity. The mechanism is that the variation of matrix rigidity tunes the balance of competition between stability of cell adhesion at cell front and instability of adhesion at cell rear, which consequently controls the driving force of cell migration. We further propose a parameter called motility factor for a quantitative description of impact of mechanical properties of matrix and cell shape on the driving force of cell migration.

  1. Cell migration or cytokinesis and proliferation? – Revisiting the “go or grow” hypothesis in cancer cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Garay, Tamás; Juhász, Éva; Molnár, Eszter [2nd Department of Pathology, Semmelweis University, Budapest (Hungary); Eisenbauer, Maria [Institute of Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Vienna (Austria); Czirók, András [Department of Biological Physics, Eötvös University, Budapest (Hungary); Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS (United States); Dekan, Barbara; László, Viktória; Hoda, Mir Alireza [Department of Thoracic Surgery, Medical University of Vienna, Vienna (Austria); Döme, Balázs [Department of Thoracic Surgery, Medical University of Vienna, Vienna (Austria); National Korányi Institute of TB and Pulmonology, Budapest (Hungary); Tímár, József [2nd Department of Pathology, Semmelweis University, Budapest (Hungary); MTA-SE Tumor Progression Research Group, Hungarian Academy of Sciences, Budapest (Hungary); Klepetko, Walter [Department of Thoracic Surgery, Medical University of Vienna, Vienna (Austria); Berger, Walter [Institute of Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Vienna (Austria); Hegedűs, Balázs, E-mail: balazs.hegedus@meduniwien.ac.at [Department of Thoracic Surgery, Medical University of Vienna, Vienna (Austria); MTA-SE Tumor Progression Research Group, Hungarian Academy of Sciences, Budapest (Hungary)

    2013-12-10

    The mortality of patients with solid tumors is mostly due to metastasis that relies on the interplay between migration and proliferation. The “go or grow” hypothesis postulates that migration and proliferation spatiotemporally excludes each other. We evaluated this hypothesis on 35 cell lines (12 mesothelioma, 13 melanoma and 10 lung cancer) on both the individual cell and population levels. Following three-day-long videomicroscopy, migration, proliferation and cytokinesis-length were quantified. We found a significantly higher migration in mesothelioma cells compared to melanoma and lung cancer while tumor types did not differ in mean proliferation or duration of cytokinesis. Strikingly, we found in melanoma and lung cancer a significant positive correlation between mean proliferation and migration. Furthermore, non-dividing melanoma and lung cancer cells displayed slower migration. In contrast, in mesothelioma there were no such correlations. Interestingly, negative correlation was found between cytokinesis-length and migration in melanoma. FAK activation was higher in melanoma cells with high motility. We demonstrate that the cancer cells studied do not defer proliferation for migration. Of note, tumor cells from various organ systems may differently regulate migration and proliferation. Furthermore, our data is in line with the observation of pathologists that highly proliferative tumors are often highly invasive. - Highlights: • We investigated the “go or grow” hypothesis in human cancer cells in vitro. • Proliferation and migration positively correlate in melanoma and lung cancer cells. • Duration of cytokinesis and migration shows inverse correlation. • Increased FAK activation is present in highly motile melanoma cells.

  2. Directional migration of cancer cells induced by a blue light intensity gradient.

    Science.gov (United States)

    Lan, Chien-Chih; Lu, Eugene Youjhen; Pan, Huei-Jyuan; Lee, Chau-Hwang

    2015-07-01

    We used a spatial light modulator to project an optical micropattern of 473 nm light with a quartic intensity gradient on a single lung cancer cell. We observed that the intracellular amounts of reactive oxygen species (ROS) of the cancer cells were proportional to the intensity of the blue light, and the blue light intensity gradients could drive directional cell migration. This optically induced directional cell migration was inhibited by a ROS scavenger in the culture medium in a dose-dependent manner. In contrast, the ROS levels in fibroblasts were saturated by the blue light at low intensity and therefore the fibroblasts did not exhibit directional migration in the intensity gradient.

  3. Regulatory domain selectivity in the cell-type specific PKN-dependence of cell migration.

    Science.gov (United States)

    Lachmann, Sylvie; Jevons, Amy; De Rycker, Manu; Casamassima, Adele; Radtke, Simone; Collazos, Alejandra; Parker, Peter J

    2011-01-01

    The mammalian protein kinase N (PKN) family of Serine/Threonine kinases comprises three isoforms, which are targets for Rho family GTPases. Small GTPases are major regulators of the cellular cytoskeleton, generating interest in the role(s) of specific PKN isoforms in processes such as cell migration and invasion. It has been reported that PKN3 is required for prostate tumour cell invasion but not PKN1 or 2. Here we employ a cell model, the 5637 bladder tumour cell line where PKN2 is relatively highly expressed, to assess the potential redundancy of these isoforms in migratory responses. It is established that PKN2 has a critical role in the migration and invasion of these cells. Furthermore, using a PKN wild-type and chimera rescue strategy, it is shown that PKN isoforms are not simply redundant in supporting migration, but appear to be linked through isoform specific regulatory domain properties to selective upstream signals. It is concluded that intervention in PKNs may need to be directed at multiple isoforms to be effective in different cell types.

  4. Regulatory domain selectivity in the cell-type specific PKN-dependence of cell migration.

    Directory of Open Access Journals (Sweden)

    Sylvie Lachmann

    Full Text Available The mammalian protein kinase N (PKN family of Serine/Threonine kinases comprises three isoforms, which are targets for Rho family GTPases. Small GTPases are major regulators of the cellular cytoskeleton, generating interest in the role(s of specific PKN isoforms in processes such as cell migration and invasion. It has been reported that PKN3 is required for prostate tumour cell invasion but not PKN1 or 2. Here we employ a cell model, the 5637 bladder tumour cell line where PKN2 is relatively highly expressed, to assess the potential redundancy of these isoforms in migratory responses. It is established that PKN2 has a critical role in the migration and invasion of these cells. Furthermore, using a PKN wild-type and chimera rescue strategy, it is shown that PKN isoforms are not simply redundant in supporting migration, but appear to be linked through isoform specific regulatory domain properties to selective upstream signals. It is concluded that intervention in PKNs may need to be directed at multiple isoforms to be effective in different cell types.

  5. Enhancement of endothelial cell migration by constitutively active LPA{sub 1}-expressing tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Kitayoshi, Misaho; Kato, Kohei; Tanabe, Eriko; Yoshikawa, Kyohei; Fukui, Rie [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Fukushima, Nobuyuki [Division of Molecular Neurobiology, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Tsujiuchi, Toshifumi, E-mail: ttujiuch@life.kindai.ac.jp [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan)

    2012-06-01

    Highlights: Black-Right-Pointing-Pointer Mutated LPA{sub 1} stimulates cell migration of endothelial cells. Black-Right-Pointing-Pointer VEGF expressions are increased by mutated LPA{sub 1}. Black-Right-Pointing-Pointer LPA signaling via mutated LPA{sub 1} is involved in angiogenesis. Black-Right-Pointing-Pointer Mutated LPA{sub 1} promotes cancer cell progression. -- Abstract: Lysophosphatidic acid (LPA) receptors belong to G protein-coupled transmembrane receptors (LPA receptors; LPA{sub 1} to LPA{sub 6}). They indicate a variety of cellular response by the interaction with LPA, including cell proliferation, migration and differentiation. Recently, we have reported that constitutive active mutated LPA{sub 1} induced the strong biological effects of rat neuroblastoma B103 cells. In the present study, we examined the effects of mutated LPA{sub 1} on the interaction between B103 cells and endothelial F-2 cells. Each LPA receptor expressing B103 cells were maintained in serum-free DMEM and cell motility assay was performed with a Cell Culture Insert. When F-2 cells were cultured with conditioned medium from Lpar1 and Lpar3-expressing cells, the cell motility of F-2 cells was significantly higher than control cells. Interestingly, the motile activity of F-2 cells was strongly induced by mutated LPA{sub 1} than other cells, correlating with the expression levels of vascular endothelial growth factor (Vegf)-A and Vegf-C. Pretreatment of LPA signaling inhibitors inhibited F-2 cell motility stimulated by mutated LPA{sub 1}. These results suggest that activation of LPA signaling via mutated LPA{sub 1} may play an important role in the promotion of angiogenesis in rat neuroblastoma cells.

  6. Physical limits of cell migration: Control by ECM space and nuclear deformation and tuning by proteolysis and traction force.

    NARCIS (Netherlands)

    Wolf, K.A.; Lindert, M.M. te; Krause, M.; Alexander, S.; Riet, J. te; Willis, A.L.; Hoffman, R.M.; Figdor, C.G.; Weiss, S.J.; Friedl, P.

    2013-01-01

    Cell migration through 3D tissue depends on a physicochemical balance between cell deformability and physical tissue constraints. Migration rates are further governed by the capacity to degrade ECM by proteolytic enzymes, particularly matrix metalloproteinases (MMPs), and integrin- and

  7. Co-regulation of cell polarization and migration by caveolar proteins PTRF/Cavin-1 and caveolin-1.

    Directory of Open Access Journals (Sweden)

    Michelle M Hill

    Full Text Available Caveolin-1 and caveolae are differentially polarized in migrating cells in various models, and caveolin-1 expression has been shown to quantitatively modulate cell migration. PTRF/cavin-1 is a cytoplasmic protein now established to be also necessary for caveola formation. Here we tested the effect of PTRF expression on cell migration. Using fluorescence imaging, quantitative proteomics, and cell migration assays we show that PTRF/cavin-1 modulates cellular polarization, and the subcellular localization of Rac1 and caveolin-1 in migrating cells as well as PKCα caveola recruitment. PTRF/cavin-1 quantitatively reduced cell migration, and induced mesenchymal epithelial reversion. Similar to caveolin-1, the polarization of PTRF/cavin-1 was dependent on the migration mode. By selectively manipulating PTRF/cavin-1 and caveolin-1 expression (and therefore caveola formation in multiple cell systems, we unveil caveola-independent functions for both proteins in cell migration.

  8. Focal adhesion kinase is involved in the migration of human osteosarcoma cells

    Science.gov (United States)

    FENG, SITAN; SHI, XIN; REN, KE; WU, SUJIA; SUN, XIAOLIANG

    2015-01-01

    The aim of the present study was to analyze the expression of focal adhesion kinase (FAK) in osteosarcoma (OS) cell lines with different migration abilities in order to determine the role of FAK in migration. A number of different 143B subclone cell lines (A1, A2, A3, A4 and A5) were obtained by a limiting dilution method, and the expression of FAK was detected using western blot analysis. The role of FAK in the migration of OS cells was investigated using small interfering RNA (siRNA), and the ratio of the number of lamellipodia was compared by immunofluorescence staining. The A2 and A3 OS 143B subclone cell lines demonstrated a stronger migration ability and exhibited higher FAK expression compared with the A1 cell line (P<0.05). Following transfection with FAK-siRNA, the migration ability of the A3 cells was significantly decreased (P<0.05), and the ratio of the number of lamellipodia formed was reduced from 35 to 11% (P<0.05). In conclusion, the level of FAK expression was higher in the cell lines with a stronger migration ability. FAK affects the migration ability of OS cells by suppressing the formation of lamellipodia. PMID:26137126

  9. The RhoGEF TEM4 Regulates Endothelial Cell Migration by Suppressing Actomyosin Contractility.

    Directory of Open Access Journals (Sweden)

    Natalia Mitin

    Full Text Available Persistent cellular migration requires efficient protrusion of the front of the cell, the leading edge where the actin cytoskeleton and cell-substrate adhesions undergo constant rearrangement. Rho family GTPases are essential regulators of the actin cytoskeleton and cell adhesion dynamics. Here, we examined the role of the RhoGEF TEM4, an activator of Rho family GTPases, in regulating cellular migration of endothelial cells. We found that TEM4 promotes the persistence of cellular migration by regulating the architecture of actin stress fibers and cell-substrate adhesions in protruding membranes. Furthermore, we determined that TEM4 regulates cellular migration by signaling to RhoC as suppression of RhoC expression recapitulated the loss-of-TEM4 phenotypes, and RhoC activation was impaired in TEM4-depleted cells. Finally, we showed that TEM4 and RhoC antagonize myosin II-dependent cellular contractility and the suppression of myosin II activity rescued the persistence of cellular migration of TEM4-depleted cells. Our data implicate TEM4 as an essential regulator of the actin cytoskeleton that ensures proper membrane protrusion at the leading edge of migrating cells and efficient cellular migration via suppression of actomyosin contractility.

  10. Tumor cell migration screen identifies SRPK1 as breast cancer metastasis determinant

    Science.gov (United States)

    van Roosmalen, Wies; Le Dévédec, Sylvia E.; Golani, Ofra; Smid, Marcel; Pulyakhina, Irina; Timmermans, Annemieke M.; Look, Maxime P.; Zi, Di; Pont, Chantal; de Graauw, Marjo; Naffar-Abu-Amara, Suha; Kirsanova, Catherine; Rustici, Gabriella; Hoen, Peter A.C. ‘t; Martens, John W.M.; Foekens, John A.; Geiger, Benjamin; van de Water, Bob

    2015-01-01

    Tumor cell migration is a key process for cancer cell dissemination and metastasis that is controlled by signal-mediated cytoskeletal and cell matrix adhesion remodeling. Using a phagokinetic track assay with migratory H1299 cells, we performed an siRNA screen of almost 1,500 genes encoding kinases/phosphatases and adhesome- and migration-related proteins to identify genes that affect tumor cell migration speed and persistence. Thirty candidate genes that altered cell migration were validated in live tumor cell migration assays. Eight were associated with metastasis-free survival in breast cancer patients, with integrin β3–binding protein (ITGB3BP), MAP3K8, NIMA-related kinase (NEK2), and SHC-transforming protein 1 (SHC1) being the most predictive. Examination of genes that modulate migration indicated that SRPK1, encoding the splicing factor kinase SRSF protein kinase 1, is relevant to breast cancer outcomes, as it was highly expressed in basal breast cancer. Furthermore, high SRPK1 expression correlated with poor breast cancer disease outcome and preferential metastasis to the lungs and brain. In 2 independent murine models of breast tumor metastasis, stable shRNA-based SRPK1 knockdown suppressed metastasis to distant organs, including lung, liver, and spleen, and inhibited focal adhesion reorganization. Our study provides comprehensive information on the molecular determinants of tumor cell migration and suggests that SRPK1 has potential as a drug target for limiting breast cancer metastasis. PMID:25774502

  11. A role for RNA post-transcriptional regulation in satellite cell activation

    Directory of Open Access Journals (Sweden)

    Farina Nicholas H

    2012-10-01

    Full Text Available Abstract Background Satellite cells are resident skeletal muscle stem cells responsible for muscle maintenance and repair. In resting muscle, satellite cells are maintained in a quiescent state. Satellite cell activation induces the myogenic commitment factor, MyoD, and cell cycle entry to facilitate transition to a population of proliferating myoblasts that eventually exit the cycle and regenerate muscle tissue. The molecular mechanism involved in the transition of a quiescent satellite cell to a transit-amplifying myoblast is poorly understood. Methods Satellite cells isolated by FACS from uninjured skeletal muscle and 12 h post-muscle injury from wild type and Syndecan-4 null mice were probed using Affymetrix 430v2 gene chips and analyzed by Spotfiretm and Ingenuity Pathway analysis to identify gene expression changes and networks associated with satellite cell activation, respectively. Additional analyses of target genes identify miRNAs exhibiting dynamic changes in expression during satellite cell activation. The function of the miRNAs was assessed using miRIDIAN hairpin inhibitors. Results An unbiased gene expression screen identified over 4,000 genes differentially expressed in satellite cells in vivo within 12 h following muscle damage and more than 50% of these decrease dramatically. RNA binding proteins and genes involved in post-transcriptional regulation were significantly over-represented whereas splicing factors were preferentially downregulated and mRNA stability genes preferentially upregulated. Furthermore, six computationally identified miRNAs demonstrated novel expression through muscle regeneration and in satellite cells. Three of the six miRNAs were found to regulate satellite cell fate. Conclusions The quiescent satellite cell is actively maintained in a state poised to activate in response to external signals. Satellite cell activation appears to be regulated by post-transcriptional gene regulation.

  12. Stretching Fibroblasts Remodels Fibronectin and Alters Cancer Cell Migration

    Science.gov (United States)

    Ao, Mingfang; Brewer, Bryson M.; Yang, Lijie; Franco Coronel, Omar E.; Hayward, Simon W.; Webb, Donna J.; Li, Deyu

    2015-02-01

    Most investigations of cancer-stroma interactions have focused on biochemical signaling effects, with much less attention being paid to biophysical factors. In this study, we investigated the role of mechanical stimuli on human prostatic fibroblasts using a microfluidic platform that was adapted for our experiments and further developed for both repeatable performance among multiple assays and for compatibility with high-resolution confocal microscopy. Results show that mechanical stretching of normal tissue-associated fibroblasts (NAFs) alters the structure of secreted fibronectin. Specifically, unstretched NAFs deposit and assemble fibronectin in a random, mesh-like arrangement, while stretched NAFs produce matrix with a more organized, linearly aligned structure. Moreover, the stretched NAFs exhibited an enhanced capability for directing co-cultured cancer cell migration in a persistent manner. Furthermore, we show that stretching NAFs triggers complex biochemical signaling events through the observation of increased expression of platelet derived growth factor receptor α (PDGFRα). A comparison of these behaviors with those of cancer-associated fibroblasts (CAFs) indicates that the observed phenotypes of stretched NAFs are similar to those associated with CAFs, suggesting that mechanical stress is a critical factor in NAF activation and CAF genesis.

  13. Aptamers Binding to c-Met Inhibiting Tumor Cell Migration.

    Directory of Open Access Journals (Sweden)

    Birgit Piater

    Full Text Available The human receptor tyrosine kinase c-Met plays an important role in the control of critical cellular processes. Since c-Met is frequently over expressed or deregulated in human malignancies, blocking its activation is of special interest for therapy. In normal conditions, the c-Met receptor is activated by its bivalent ligand hepatocyte growth factor (HGF. Also bivalent antibodies can activate the receptor by cross linking, limiting therapeutic applications. We report the generation of the RNA aptamer CLN64 containing 2'-fluoro pyrimidine modifications by systematic evolution of ligands by exponential enrichment (SELEX. CLN64 and a previously described single-stranded DNA (ssDNA aptamer CLN3 exhibited high specificities and affinities to recombinant and cellular expressed c-Met. Both aptamers effectively inhibited HGF-dependent c-Met activation, signaling and cell migration. We showed that these aptamers did not induce c-Met activation, revealing an advantage over bivalent therapeutic molecules. Both aptamers were shown to bind overlapping epitopes but only CLN3 competed with HGF binding to cMet. In addition to their therapeutic and diagnostic potential, CLN3 and CLN64 aptamers exhibit valuable tools to further understand the structural and functional basis for c-Met activation or inhibition by synthetic ligands and their interplay with HGF binding.

  14. EGF receptor signalling is essential for electric-field-directed migration of breast cancer cells.

    Science.gov (United States)

    Pu, Jin; McCaig, Colin D; Cao, Lin; Zhao, Zhiqiang; Segall, Jeffrey E; Zhao, Min

    2007-10-01

    The mechanisms by which cancer cells migrate to metastasise are not fully understood. Breast cancers are accompanied by electrical depolarisation of tumour epithelial cells. The electrical changes can be detected on the skin and are used to differentiate malignant from benign breast tumours. Could the electrical signals play a role in metastasis by promoting tumour cell migration? We report that electric fields stimulate and direct migration of human breast cancer cells. Importantly, these effects were more significant in highly metastatic tumour cells than in low metastatic tumour cells. Electric-field-enhanced directional migration correlates well with the expression level of EGF receptor (EGFR/ErbB1). To confirm this, we transfected low metastatic clone MTC cells with human ErbB1, which significantly increased the electrotactic response. Inhibition of ErbB1 completely abolished the directional response of MTLn3 cells to an electric field. Transfection of MTLn3 cells and MDA-MB-435 cells with expression vectors for ErbB family members ErbB1, ErbB2 and ErbB3 also significantly enhanced EF-induced migration. These results suggest that electric signals might play a role in metastasis of breast cancers by enhancing cell migration through the ErbB-signalling pathway.

  15. Aquaporin 1 Facilitated Hepatocellular Carcinoma SMMC7221 Cell Migration Associated with Water Permeability

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ai-li; LI Jiang; WANG Yan-qing; ZAKNROU Zohra; MA Tong-hui; LI Xiao-meng

    2011-01-01

    The authors investigated the regulation of human aquaporin l(hAQPl) and the involvement of aquaporin l(AQPl) in the migration of human hepatocellular carcinoma SMMC-7221 cells using RNA intereference technology.Firstly, two short hairpin RNA(shRNA) constructs in PBSU6 vector were reconstructed and their knockdown effects were identified in SMMC-7221 cells. Next, the involvement of endogenous hAQPl in regulating the migration of SMMC-7221 cells was investigated via siRNA technology. HAQPl-shRNA can specifically inhibit AQPl dependent osmotic water permeability. Meanwhile the migration of SMMC-7221 cells was inhibited remarkably after silencing AQPl by performing transwell cell migration assay and in vitro wound healing assay. Furthermore, in the presence of an inhibitor HgCl2, the water permeability of the cell membrane was remarkably decreased, the expression of AQPl was upregulated after HgCl2 treatment and the cell movement was decreased at the moment. Increased AQPl cannot attenuate cell migration ability when cell membrane loses its water permeability function. This demonstrates that the cell migration was remarkably related to the transporting water function of cell membrane.

  16. Regulatory Domain Selectivity in the Cell-Type Specific PKN-Dependence of Cell Migration

    OpenAIRE

    Sylvie Lachmann; Amy Jevons; Manu De Rycker; Adele Casamassima; Simone Radtke; Alejandra Collazos; Peter J Parker

    2011-01-01

    The mammalian protein kinase N (PKN) family of Serine/Threonine kinases comprises three isoforms, which are targets for Rho family GTPases. Small GTPases are major regulators of the cellular cytoskeleton, generating interest in the role(s) of specific PKN isoforms in processes such as cell migration and invasion. It has been reported that PKN3 is required for prostate tumour cell invasion but not PKN1 or 2. Here we employ a cell model, the 5637 bladder tumour cell line where PKN2 is relativel...

  17. Phosphatidylinositol 4-phosphate in the Golgi apparatus regulates cell-cell adhesion and invasive cell migration in human breast cancer.

    Science.gov (United States)

    Tokuda, Emi; Itoh, Toshiki; Hasegawa, Junya; Ijuin, Takeshi; Takeuchi, Yukiko; Irino, Yasuhiro; Fukumoto, Miki; Takenawa, Tadaomi

    2014-06-01

    Downregulation of cell-cell adhesion and upregulation of cell migration play critical roles in the conversion of benign tumors to aggressive invasive cancers. In this study, we show that changes in cell-cell adhesion and cancer cell migration/invasion capacity depend on the level of phosphatidylinositol 4-phosphate [PI(4)P] in the Golgi apparatus in breast cancer cells. Attenuating SAC1, a PI(4)P phosphatase localized in the Golgi apparatus, resulted in decreased cell-cell adhesion and increased cell migration in weakly invasive cells. In contrast, silencing phosphatidylinositol 4-kinase IIIβ, which generates PI(4)P in the Golgi apparatus, increased cell-cell adhesion and decreased invasion in highly invasive cells. Furthermore, a PI(4)P effector, Golgi phosphoprotein 3, was found to be involved in the generation of these phenotypes in a manner that depends on its PI(4)P-binding ability. Our results provide a new model for breast cancer cell progression in which progression is controlled by PI(4)P levels in the Golgi apparatus.

  18. Time-lapse cinematography of the capillary tube cell migration inhibition test.

    Science.gov (United States)

    Bray, M A

    1980-01-01

    The kinetics of human and guinea pig cell migration inhibition have been studied using time-lapse cinematography of cells migrating from capillary tubes. Guinea pig and human cells exhibit markedly different kinetics in the absence of inhibitors. Specific antigen causes a dose-related inhibition of migration for up to 60 h using guinea pig cells and a peak of inhibition after 18 h using the human leucocyte system. The timing of measurement of maximum activity more critical for the latter test. The kinetics of lymphokine generation have been examined and the migration inhibitory activity of the plant mitogen (PHA), a Kurloff cell product and a continuous cell line supernatant have been compared with the inhibitory profiles of lymphokine preparations and specific antigen.

  19. Controlled skeletal progenitor cell migration on nanostructured porous silicon/silicon micropatterns

    Science.gov (United States)

    Torres-Costa, V.; Sánchez-Vaquero, V.; Muñoz-Noval, Á.; González-Méndez, L.; Punzón-Quijorna, E.; Gallach-Pérez, D.; Manso-Silván, M.; Martínez-Muñoz, G.; Climent-Font, A.; García-Ruiz, J. P.; Martín-Palma, R. J.

    2011-10-01

    In this work nanostructured porous silicon (nanoPS) was used for the fabrication of surface micropatterns aiming at controlling cell adhesion and migration. In particular, surface patterns of nanoPS and Si were engineered by high-energy ion-beam irradiation and subsequent anodization. It was found that human skeletal progenitor cells are sensitive to oneand two-dimensional patterns and that focal adhesion is inhibited on nanoPS areas. In spite of this anti-fouling characteristics, studies on patterns with reduced Si areas show that cells conform to nanoPS pathways favoring migration through cell protrusion, body translocation and tail retraction from two parallel Si traction rails. Moreover, migration can be blocked and cells tend to arrange when grid patterns with the appropriate dimensions are fabricated. The experimental results confirm that progenitor cells are able to exploit nanoPS anti-fouling designs by adapting to it for migration purposes.

  20. The Exposure of Breast Cancer Cells to Fulvestrant and Tamoxifen Modulates Cell Migration Differently

    Directory of Open Access Journals (Sweden)

    Dionysia Lymperatou

    2013-01-01

    Full Text Available There is no doubt that there are increased benefits of hormonal therapy to breast cancer patients; however, current evidence suggests that estrogen receptor (ER blockage using antiestrogens is associated with a small induction of invasiveness in vitro. The mechanism by which epithelial tumor cells escape from the primary tumor and colonize to a distant site is not entirely understood. This study investigates the effect of two selective antagonists of the ER, Fulvestrant (Fulv and Tamoxifen (Tam, on the invasive ability of breast cancer cells. We found that 17β-estradiol (E2 demonstrated a protective role regarding cell migration and invasion. Fulv did not alter this effect while Tam stimulated active cell migration according to an increase in Snail and a decrease in E-cadherin protein expression. Furthermore, both tested agents increased expression of matrix metalloproteinases (MMPs and enhanced invasive potential of breast cancer cells. These changes were in line with focal adhesion kinase (FAK rearrangement. Our data indicate that the anti-estrogens counteracted the protective role of E2 concerning migration and invasion since their effect was not limited to antiproliferative events. Although Fulv caused a less aggressive result compared to Tam, the benefits of hormonal therapy concerning invasion and metastasis yet remain to be investigated.

  1. Nicotine enhances migration and invasion of human esophageal squamous carcinoma cells which is inhibited by nimesulide

    Institute of Scientific and Technical Information of China (English)

    Ye Zong; Shu-Tian Zhang; Sheng-Tao Zhu

    2009-01-01

    AIM:To study the effect of nicotine on the migration and invasion of human esophageal squamous carcinoma cells and to investigate whether nimesulide can inhibit the effect of nicotine. METHODS:The esophageal squamous carcinoma cell line (TE-13) was treated with different concentrations of nicotine (100 mg/mL and 200 mg/mL) or 200 mg/mL nicotine plus 100 mmol/L nimesulide. Cell migration and invasion were measured using migration and invasion chamber systems. COX-2 expression was determined by Western blotting. Matrix metalloproteinase-2 (MMP-2) was analyzed by zymography and ELISA. RESULTS:Nicotine (100 mg/mL, 200 mg/mL) enhanced TE-13 cells migration and invasion, and increased the protein expression of COX-2 and the activity of MMP-2. Nicotine (200 mg/mL) stimulated TE-13 cells migration and invasion which were partly blocked by nimesulide. This was associated with decreased protein expression of COX-2 and decreased activity and protein expression of MMP-2.CONCLUSION:Nicotine enhances the migration and invasion of the esophageal squamous carcinoma cell line, and nimesulide partly blocks the effect of nicotine-enhanced esophageal squamous carcinoma cell migration and invasion.

  2. Suppression of calpain expression by NSAIDs is associated with inhibition of cell migration in rat duodenum.

    Science.gov (United States)

    Silver, Kristopher; Littlejohn, A; Thomas, Laurel; Bawa, Bhupinder; Lillich, James D

    2017-05-15

    Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for the alleviation of pain and inflammation, but these drugs are also associated with a suite of negative side effects. Gastrointestinal (GI) toxicity is particularly concerning since it affects an estimated 70% of individuals taking NSAIDs routinely, and evidence suggests the majority of toxicity is occurring in the small intestine. Traditionally, NSAID-induced GI toxicity has been associated with indiscriminate inhibition of cyclooxygenase isoforms, but other mechanisms, including inhibition of cell migration, intestinal restitution, and wound healing, are likely to contribute to toxicity. Previous efforts demonstrated that treatment of cultured intestinal epithelial cells (IEC) with NSAIDs inhibits expression and activity of calpain proteases, but the effects of specific inhibition of calpain expression in vitro or the effects of NSAIDs on intestinal cell migration in vivo remain to be determined. Accordingly, we examined the effect of suppression of calpain protease expression with siRNA on cell migration in cultured IECs and evaluated the effects of NSAID treatment on epithelial cell migration and calpain protease expression in rat duodenum. Our results show that calpain siRNA inhibits protease expression and slows migration in cultured IECs. Additionally, NSAID treatment of rats slowed migration up the villus axis and suppressed calpain expression in duodenal epithelial cells. Our results are supportive of the hypothesis that suppression of calpain expression leading to slowing of cell migration is a potential mechanism through which NSAIDs cause GI toxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Crawling and Gliding: A Computational Model for Shape-Driven Cell Migration.

    Science.gov (United States)

    Niculescu, Ioana; Textor, Johannes; de Boer, Rob J

    2015-10-01

    Cell migration is a complex process involving many intracellular and extracellular factors, with different cell types adopting sometimes strikingly different morphologies. Modeling realistically behaving cells in tissues is computationally challenging because it implies dealing with multiple levels of complexity. We extend the Cellular Potts Model with an actin-inspired feedback mechanism that allows small stochastic cell rufflings to expand to cell protrusions. This simple phenomenological model produces realistically crawling and deforming amoeboid cells, and gliding half-moon shaped keratocyte-like cells. Both cell types can migrate randomly or follow directional cues. They can squeeze in between other cells in densely populated environments or migrate collectively. The model is computationally light, which allows the study of large, dense and heterogeneous tissues containing cells with realistic shapes and migratory properties.

  4. Crawling and Gliding: A Computational Model for Shape-Driven Cell Migration.

    Directory of Open Access Journals (Sweden)

    Ioana Niculescu

    2015-10-01

    Full Text Available Cell migration is a complex process involving many intracellular and extracellular factors, with different cell types adopting sometimes strikingly different morphologies. Modeling realistically behaving cells in tissues is computationally challenging because it implies dealing with multiple levels of complexity. We extend the Cellular Potts Model with an actin-inspired feedback mechanism that allows small stochastic cell rufflings to expand to cell protrusions. This simple phenomenological model produces realistically crawling and deforming amoeboid cells, and gliding half-moon shaped keratocyte-like cells. Both cell types can migrate randomly or follow directional cues. They can squeeze in between other cells in densely populated environments or migrate collectively. The model is computationally light, which allows the study of large, dense and heterogeneous tissues containing cells with realistic shapes and migratory properties.

  5. Piperine impairs the migration and T cell-activating function of dendritic cells.

    Science.gov (United States)

    Rodgers, Gemma; Doucette, Carolyn D; Soutar, David A; Liwski, Robert S; Hoskin, David W

    2016-02-03

    Piperine, a major alkaloid found in the fruits of black and long pepper plants, has anti-inflammatory properties; however, piperine's effect on dendritic cell (DC) migration and T cell-activating function has not been investigated. Bone marrow-derived mouse DCs that were matured in the presence of 100 μM piperine showed reduced in vitro migration in response to CCL21, as well as reduced in vivo migration to lymph nodes. In addition, piperine-treated DCs had reduced CCR7 expression and elevated CCR5 expression, as well as reduced expression of CD40 and class II major histocompatibility complex molecules and decreased nuclear accumulation of RelB. DC production of interleukin (IL)-6, tumor necrosis factor α, and monocyte chemoattractant protein-1 in response to lipopolysaccharide stimulation was also reduced following piperine treatment. Exposure to piperine during maturation therefore caused DCs to retain an immature phenotype, which was associated with a reduced capacity to promote T cell activation since co-culture of ovalbumin (OVA323-339)-specific T cells with OVA323-339-pulsed DCs that were previously matured in the presence of piperine showed reduced interferon-γ and IL-2 expression. OVA323-339-specific T cell proliferation was also reduced in vivo in the presence of piperine-treated DCs. Inhibition of DC migration and function by piperine may therefore be a useful strategy to down-regulate potentially harmful DC-driven T cell responses to self-antigens and transplantation antigens.

  6. Luteolin inhibits lung metastasis, cell migration, and viability of triple-negative breast cancer cells

    Science.gov (United States)

    Cook, Matthew T; Liang, Yayun; Besch-Williford, Cynthia; Hyder, Salman M

    2017-01-01

    Most breast cancer-related deaths from triple-negative breast cancer (TNBC) occur following metastasis of cancer cells and development of tumors at secondary sites. Because TNBCs lack the three receptors targeted by current chemotherapeutic regimens, they are typically treated with extremely aggressive and highly toxic non-targeted treatment strategies. Women with TNBC frequently develop metastatic lesions originating from drug-resistant residual cells and have poor prognosis. For this reason, novel therapeutic strategies that are safer and more effective are sought. Luteolin (LU) is a naturally occurring, non-toxic plant compound that has proven effective against several types of cancer. With this in mind, we conducted in vivo and in vitro studies to determine whether LU might suppress metastasis of TNBC. In an in vivo mouse metastasis model, LU suppressed metastasis of human MDA-MB-435 and MDA-MB-231 (4175) LM2 TNBC cells to the lungs. In in vitro assays, LU inhibited cell migration and viability of MDA-MB-435 and MDA-MB-231 (4175) LM2 cells. Further, LU induced apoptosis in MDA-MB-231 (4175) LM2 cells. Relatively low levels (10 µM) of LU significantly inhibited vascular endothelial growth factor (VEGF) secretion in MDA-MB-231 (4175) LM2 cells, suggesting that it has the ability to suppress a potent angiogenic and cell survival factor. In addition, migration of MDA-MB-231 (4175) LM2 cells was inhibited upon exposure to an antibody against the VEGF receptor, KDR, but not by exposure to a VEGF165 antibody. Collectively, these data suggest that the anti-metastatic properties of LU may, in part, be due to its ability to block VEGF production and KDR-mediated activity, thereby inhibiting tumor cell migration. These studies suggest that LU deserves further investigation as a potential treatment option for women with TNBC. PMID:28096694

  7. Spatial regulation of the cAMP-dependent protein kinase during chemotactic cell migration

    OpenAIRE

    Howe, Alan K.; Baldor, Linda C.; Hogan, Brian P.

    2005-01-01

    Historically, the cAMP-dependent protein kinase (PKA) has a paradoxical role in cell motility, having been shown to both facilitate and inhibit actin cytoskeletal dynamics and cell migration. In an effort to understand this dichotomy, we show here that PKA is regulated in subcellular space during cell migration. Immunofluorescence microscopy and biochemical enrichment of pseudopodia showed that type II regulatory subunits of PKA and PKA activity are enriched in protrusive cellular structures ...

  8. Androgen-induced cell migration: role of androgen receptor/filamin A association.

    Directory of Open Access Journals (Sweden)

    Gabriella Castoria

    Full Text Available BACKGROUND: Androgen receptor (AR controls male morphogenesis, gametogenesis and prostate growth as well as development of prostate cancer. These findings support a role for AR in cell migration and invasiveness. However, the molecular mechanism involved in AR-mediated cell migration still remains elusive. METHODOLOGY/PRINCIPAL FINDINGS: Mouse embryo NIH3T3 fibroblasts and highly metastatic human fibrosarcoma HT1080 cells harbor low levels of transcriptionally incompetent AR. We now report that, through extra nuclear action, AR triggers migration of both cell types upon stimulation with physiological concentrations of the androgen R1881. We analyzed the initial events leading to androgen-induced cell migration and observed that challenging NIH3T3 cells with 10 nM R1881 rapidly induces interaction of AR with filamin A (FlnA at cytoskeleton. AR/FlnA complex recruits integrin beta 1, thus activating its dependent cascade. Silencing of AR, FlnA and integrin beta 1 shows that this ternary complex controls focal adhesion kinase (FAK, paxillin and Rac, thereby driving cell migration. FAK-null fibroblasts migrate poorly and Rac inhibition by EHT impairs motility of androgen-treated NIH3T3 cells. Interestingly, FAK and Rac activation by androgens are independent of each other. Findings in human fibrosarcoma HT1080 cells strengthen the role of Rac in androgen signaling. The Rac inhibitor significantly impairs androgen-induced migration in these cells. A mutant AR, deleted of the sequence interacting with FlnA, fails to mediate FAK activation and paxillin tyrosine phosphorylation in androgen-stimulated cells, further reinforcing the role of AR/FlnA interaction in androgen-mediated motility. CONCLUSIONS/SIGNIFICANCE: The present report, for the first time, indicates that the extra nuclear AR/FlnA/integrin beta 1 complex is the key by which androgen activates signaling leading to cell migration. Assembly of this ternary complex may control organ development

  9. Thymosin beta 4 induces hair growth via stem cell migration and differentiation.

    Science.gov (United States)

    Philp, Deborah; St-Surin, Sharleen; Cha, Hee-Jae; Moon, Hye-Sung; Kleinman, Hynda K; Elkin, Michael

    2007-09-01

    Thymosin beta 4 is a small 43-amino-acid molecule that has multiple biological activities, including promotion of cell migration angiogenesis, cell survival, protease production, and wound healing. We have found that thymosin beta 4 promotes hair growth in various rat and mice models including a transgenic thymosin beta 4 overexpressing mouse. We have also determined the mechanism by which thymosin beta 4 acts to promote hair growth by examining its effects on follicle stem cell growth, migration, differentiation, and protease production.

  10. Stimulation of cortical myosin phosphorylation by p114RhoGEF drives cell migration and tumor cell invasion.

    Directory of Open Access Journals (Sweden)

    Stephen J Terry

    Full Text Available Actinomyosin activity is an important driver of cell locomotion and has been shown to promote collective cell migration of epithelial sheets as well as single cell migration and tumor cell invasion. However, the molecular mechanisms underlying activation of cortical myosin to stimulate single cell movement, and the relationship between the mechanisms that drive single cell locomotion and those that mediate collective cell migration of epithelial sheets are incompletely understood. Here, we demonstrate that p114RhoGEF, an activator of RhoA that associates with non-muscle myosin IIA, regulates collective cell migration of epithelial sheets and tumor cell invasion. Depletion of p114RhoGEF resulted in specific spatial inhibition of myosin activation at cell-cell contacts in migrating epithelial sheets and the cortex of migrating single cells, but only affected double and not single phosphorylation of myosin light chain. In agreement, overall elasticity and contractility of the cells, processes that rely on persistent and more constant forces, were not affected, suggesting that p114RhoGEF mediates process-specific myosin activation. Locomotion was p114RhoGEF-dependent on Matrigel, which favors more roundish cells and amoeboid-like actinomyosin-driven movement, but not on fibronectin, which stimulates flatter cells and lamellipodia-driven, mesenchymal-like migration. Accordingly, depletion of p114RhoGEF led to reduced RhoA, but increased Rac activity. Invasion of 3D matrices was p114RhoGEF-dependent under conditions that do not require metalloproteinase activity, supporting a role of p114RhoGEF in myosin-dependent, amoeboid-like locomotion. Our data demonstrate that p114RhoGEF drives cortical myosin activation by stimulating myosin light chain double phosphorylation and, thereby, collective cell migration of epithelial sheets and amoeboid-like motility of tumor cells.

  11. A key role for PTP1B in dendritic cell maturation, migration, and T cell activation.

    Science.gov (United States)

    Martin-Granados, Cristina; Prescott, Alan R; Le Sommer, Samantha; Klaska, Izabela P; Yu, Tian; Muckersie, Elizabeth; Giuraniuc, Claudiu V; Grant, Louise; Delibegovic, Mirela; Forrester, John V

    2015-12-01

    Dendritic cells (DC) are the major antigen-presenting cells bridging innate and adaptive immunity, a function they perform by converting quiescent DC to active, mature DC with the capacity to activate naïve T cells. They do this by migrating from the tissues to the T cell area of the secondary lymphoid tissues. Here, we demonstrate that myeloid cell-specific genetic deletion of PTP1B (LysM PTP1B) leads to defects in lipopolysaccharide-driven bone marrow-derived DC (BMDC) activation associated with increased levels of phosphorylated Stat3. We show that myeloid cell-specific PTP1B deletion also causes decreased migratory capacity of epidermal DC, as well as reduced CCR7 expression and chemotaxis to CCL19 by BMDC. PTP1B deficiency in BMDC also impairs their migration in vivo. Further, immature LysM PTP1B BMDC display fewer podosomes, increased levels of phosphorylated Src at tyrosine 527, and loss of Src localization to podosome puncta. In co-culture with T cells, LysM PTP1B BMDC establish fewer and shorter contacts than control BMDC. Finally, LysM PTP1B BMDC fail to present antigen to T cells as efficiently as control BMDC. These data provide first evidence for a key regulatory role for PTP1B in mediating a central DC function of initiating adaptive immune responses in response to innate immune cell activation.

  12. Cdc42-dependent leading edge coordination is essential for interstitial dendritic cell migration

    DEFF Research Database (Denmark)

    Lammermann, Tim; Renkawitz, Jorg; Wu, Xunwei;

    2009-01-01

    Mature dendritic cells (DCs) moving from the skin to the lymph node are a prototypic example of rapidly migrating amoeboid leukocytes. Interstitial DC migration is directionally guided by chemokines, but independent of specific adhesive interactions with the tissue as well as pericellular...

  13. G protein-coupled receptor kinase 2 positively regulates epithelial cell migration

    NARCIS (Netherlands)

    Penela, Petronila; Ribas, Catalina; Aymerich, Ivette; Eijkelkamp, Niels; Barreiro, Olga; Heijnen, Cobi J.; Kavelaars, Annemieke; Sanchez-Madrid, Francisco; Mayor, Federico

    2008-01-01

    Cell migration requires integration of signals arising from both the extracellular matrix and messengers acting through G protein-coupled receptors (GPCRs). We find that increased levels of G protein-coupled receptor kinase 2 (GRK2), a key player in GPCR regulation, poteniate migration of epithelial

  14. A microfluidic wound-healing assay for quantifying endothelial cell migration

    NARCIS (Netherlands)

    van der Meer, Andries Dirk; Vermeul, Kim; Poot, Andreas A.; Feijen, Jan; Vermes, I.

    A microfluidic wound-healing assay for quantifying endothelial cell migration. Am J Physiol Heart Circ Physiol 298: H719–H725, 2010. First published November 20, 2009; doi:10.1152/ajpheart.00933.2009.—Endothelial migration is an important process in the formation of blood vessels and the repair of

  15. A two-step model for Langerhans cell migration to skin-draining LN

    OpenAIRE

    2008-01-01

    Although the role of Langerhans cells (LC) in skin immune responses is still a matter of debate, it is known that LC require the chemokine receptor CCR7 for migrating to skin-draining LN. A report in the current issue of the European Journal of Immunology unfolds some of the intricacies of LC migration, showing that LC need CXCR4, but not CCR7, for their migration from the epidermis to the dermis. Thus, LC migration to skin-draining LN occurs in two distinct phases: a first step from the epid...

  16. Microfluidic chip with integrated electrical cell-impedance sensing for monitoring single cancer cell migration in three-dimensional matrixes.

    Science.gov (United States)

    Nguyen, Tien Anh; Yin, Tsung-I; Reyes, Diego; Urban, Gerald A

    2013-11-19

    Cell migration has been recognized as one hallmark of malignant tumor progression. By integrating the method of electrical cell-substrate impedance sensing (ECIS) with the Boyden chamber design, the state-of-the-art techniques provide kinetic information about cell migration and invasion processes in three-dimensional (3D) extracellular matrixes. However, the information related to the initial stage of cell migration with single-cell resolution, which plays a unique role in the metastasis-invasion cascade of cancer, is not yet available. In this paper, we present a microfluidic device integrated with ECIS for investigating single cancer cell migration in 3D matrixes. Using microfluidics techniques without the requirement of physical connections to off-chip pneumatics, the proposed sensor chip can efficiently capture single cells on microelectrode arrays for sequential on-chip 2D or 3D cell culture and impedance measurement. An on-chip single-cell migration assay was successfully demonstrated within several minutes. Migration of single metastatic MDA-MB-231 cells in their initial stage can be monitored in real time; it shows a rapid change in impedance magnitude of approximately 10 Ω/s, whereas no prominent impedance change is observed for less-metastasis MCF-7 cells. The proposed sensor chip, allowing for a rapid and selective detection of the migratory properties of cancer cells at the single-cell level, could be applied as a new tool for cancer research.

  17. Collective migration models: Dynamic monitoring of leader cells in migratory/invasive disease processes

    Science.gov (United States)

    Dean, Zachary Steven

    Leader cells are a fundamental biological process that have only been investigated since the early 2000s. These cells have often been observed emerging at the edge of an artificial wound in 2D epithelial cell collective invasion, created with either a mechanical scrape from a pipette tip or from the removal of a plastic, physical blocker. During migration, the moving cells maintain cell-cell contacts, an important quality of collective migration; the leader cells originate from either the first or the second row, they increase in size compared to other cells, and they establish ruffled lamellipodia. Recent studies in 3D have also shown that cells emerging from an invading collective group that also exhibit leader-like properties. Exactly how leader cells influence and interact with follower cells as well as other cells types during collective migration, however, is another matter, and is a subject of intense investigation between many different labs and researchers. The majority of leader cell research to date has involved epithelial cells, but as collective migration is implicated in many different pathogenic diseases, such as cancer and wound healing, a better understanding of leader cells in many cell types and environments will allow significant improvement to therapies and treatments for a wide variety of disease processes. In fact, more recent studies on collective migration and invasion have broadened the field to include other cell types, including mesenchymal cancer cells and fibroblasts. However, the proper technology for picking out dynamic, single cells within a moving and changing cell population over time has severely limited previous investigation into leader cell formation and influence over other cells. In line with these previous studies, we not only bring new technology capable of dynamically monitoring leader cell formation, but we propose that leader cell behavior is more than just an epithelial process, and that it is a critical physiological

  18. Concentric Gel System to Study the Biophysical Role of Matrix Microenvironment on 3D Cell Migration

    Science.gov (United States)

    Kurniawan, Nicholas Agung; Chaudhuri, Parthiv Kant; Lim, Chwee Teck

    2015-01-01

    The ability of cells to migrate is crucial in a wide variety of cell functions throughout life from embryonic development and wound healing to tumor and cancer metastasis. Despite intense research efforts, the basic biochemical and biophysical principles of cell migration are still not fully understood, especially in the physiologically relevant three-dimensional (3D) microenvironments. Here, we describe an in vitro assay designed to allow quantitative examination of 3D cell migration behaviors. The method exploits the cell’s mechanosensing ability and propensity to migrate into previously unoccupied extracellular matrix (ECM). We use the invasion of highly invasive breast cancer cells, MDA-MB-231, in collagen gels as a model system. The spread of cell population and the migration dynamics of individual cells over weeks of culture can be monitored using live-cell imaging and analyzed to extract spatiotemporally-resolved data. Furthermore, the method is easily adaptable for diverse extracellular matrices, thus offering a simple yet powerful way to investigate the role of biophysical factors in the microenvironment on cell migration. PMID:25867104

  19. A Cellular Potts Model simulating cell migration on and in matrix environments.

    Science.gov (United States)

    Scianna, Marco; Preziosi, Luigi; Wolf, Katarina

    2013-02-01

    Cell migration on and through extracellular matrix is fundamental in a wide variety of physiological and pathological phenomena, and is exploited in scaffold-based tissue engineering. Migration is regulated by a number of extracellular matrix- or cell-derived biophysical parameters, such as matrix fiber orientation, pore size, and elasticity, or cell deformation, proteolysis, and adhesion. We here present an extended Cellular Potts Model (CPM) able to qualitatively and quantitatively describe cell migration efficiencies and phenotypes both on two-dimensional substrates and within three-dimensional matrices, close to experimental evidence. As distinct features of our approach, cells are modeled as compartmentalized discrete objects, differentiated into nucleus and cytosolic region, while the extracellular matrix is composed of a fibrous mesh and a homogeneous fluid. Our model provides a strong correlation of the directionality of migration with the topological extracellular matrix distribution and a biphasic dependence of migration on the matrix structure, density, adhesion, and stiffness, and, moreover, simulates that cell locomotion in highly constrained fibrillar obstacles requires the deformation of the cell's nucleus and/or the activity of cell-derived proteolysis. In conclusion, we here propose a mathematical modeling approach that serves to characterize cell migration as a biological phenomenon in healthy and diseased tissues and in engineering applications.

  20. Inhibition of Cdc42 is essential for Mig-6 suppression of cell migration induced by EGF.

    Science.gov (United States)

    Jiang, Xinni; Niu, MengMeng; Chen, Deshi; Chen, Jing; Cao, Yang; Li, Xiaorong; Ying, Haoqiang; Bergholz, Johann; Zhang, Yujun; Xiao, Zhi-Xiong

    2016-08-02

    The adaptor protein Mig-6 is a negative regulator of EGF signaling. It is shown that Mig-6 inhibits cell migration via direct interaction with the ErbB receptors, thereby inhibiting cross-phosphorylation or targeting the receptors for degradation. Mig-6 has also been shown to bind to and inhibit the Rho GTPase Cdc42 to suppress cytoskeletal rearrangement. However, the molecular mechanism(s) by which Mig-6 inhibits cell migration via Cdc42 is still not entirely clear. Here, we show that Mig-6 binding to Cdc42 is necessary and sufficient to inhibit EGF-induced filopodia formation and migration. This binding, mediated by four specific residues (I11, R12, M26, R30) in the Mig-6 CRIB domain, is essential for Mig-6 function. In addition, ectopic expression of Cdc42 reverses Mig-6 inhibition of cell migration. Mig-6 CRIB domain, alone, is sufficient to inhibit cell migration. Conversely, Mig-6 binding to EGFR is dispensable for Mig-6-mediated inhibition of cell migration. Moreover, we found that decreased Mig-6 expression correlates with cancer progression in breast and prostate cancers. Together, our results demonstrate that Mig-6 inhibition of Cdc42 signaling is critical in Mig-6 function to suppress cell migration and that dysregulation of this pathway may play a critical role in cancer development.

  1. Impaired energy metabolism of senescent muscle satellite cells is associated with oxidative modifications of glycolytic enzymes

    DEFF Research Database (Denmark)

    Baraibar, Martín A; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina

    2016-01-01

    Accumulation of oxidized proteins is a hallmark of cellular and organismal aging. Adult muscle stem cell (or satellite cell) replication and differentiation is compromised with age contributing to sarcopenia. However, the molecular events related to satellite cell dysfunction during aging are not...

  2. Stable SET knockdown in breast cell carcinoma inhibits cell migration and invasion

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jie [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Yang, Xi-fei [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Ren, Xiao-hu [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Meng, Xiao-jing [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Huang, Hai-yan [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Zhao, Qiong-hui [Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen (China); Yuan, Jian-hui; Hong, Wen-xu; Xia, Bo; Huang, Xin-feng; Zhou, Li [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Liu, Jian-jun, E-mail: bio-research@hotmail.com [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Zou, Fei, E-mail: zoufei616@163.com [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China)

    2014-10-10

    Highlights: • We employed RNA interference to knockdown SET expression in breast cancer cells. • Knockdown of SET expression inhibits cell proliferation, migration and invasion. • Knockdown of SET expression increases the activity and expression of PP2A. • Knockdown of SET expression decreases the expression of MMP-9. - Abstract: Breast cancer is the most malignant tumor for women, however, the mechanisms underlying this devastating disease remain unclear. SET is an endogenous inhibitor of protein phosphatase 2A (PP2A) and involved in many physiological and pathological processes. SET could promote the occurrence of tumor through inhibiting PP2A. In this study, we explore the role of SET in the migration and invasion of breast cancer cells MDA-MB-231 and ZR-75-30. The stable suppression of SET expression through lentivirus-mediated RNA interference (RNAi) was shown to inhibit the growth, migration and invasion of breast cancer cells. Knockdown of SET increases the activity and expression of PP2Ac and decrease the expression of matrix metalloproteinase 9 (MMP-9). These data demonstrate that SET may be involved in the pathogenic processes of breast cancer, indicating that SET can serve as a potential therapeutic target for the treatment of breast cancer.

  3. Dependence of sea urchin primary mesenchyme cell migration on xyloside- and sulfate-sensitive cell surface-associated components.

    Science.gov (United States)

    Lane, M C; Solursh, M

    1988-05-01

    The migration of sea urchin primary mesenchyme cells (PMC) is inhibited in embryos cultured in sulfate-free seawater and in seawater containing exogenous xylosides. In the present study, primary mesenchyme cells and extra-cellular matrix have been isolated from normal and treated Lytechinus pictus and Strongylocentrotus purpuratus embryos and recombined in an in vitro migration assay to determine whether the cells or the matrix are migration defective. Normal cells were found to migrate on either normal or treated matrix, whereas sulfate-deprived and xyloside-treated PMC failed to migrate in vitro on normal and treated substrata. Migratory ability can be restored to defective cells by returning the PMC to normal seawater, or by exposing the defective cells to materials removed from the surface of normal cells with 1 M urea. The similarity of the results obtained with sulfate-deprived and xyloside-treated PMC suggested that a common molecule may be affected by the two treatments. As a first test of this possibility, xyloside-treated S. purpuratus PMC were given the urea extract prepared from sulfate-deprived S. purpuratus PMC, and this extract did not restore migratory ability. These findings indicate that PMC normally synthesize a surface-associated molecule that is involved in cell migration, and the sensitivity to exogenous xylosides and sulfate deprivation suggests that a sulfated proteoglycan may be involved in primary mesenchyme cell migration.

  4. Autocrine CCL19 blocks dendritic cell migration toward weak gradients of CCL21

    DEFF Research Database (Denmark)

    Hansen, Morten; Met, Özcan; Larsen, Niels Bent

    2016-01-01

    the effect of autocrine CCL19 on in vitro migration of human DCs toward CCL21. Results. Using human monocyte-derived DCs in a 3D chemotaxis assay, we are the first to demonstrate that CCL19 more potently induces directed migration of human DCs compared with CCL21. When comparing migration of type 1 DCs......Background aims. Maturation of dendritic cells (DCs) induces their homing from peripheral to lymphatic tissues guided by CCL21. However, in vitro matured human monocyte-derived DC cancer vaccines injected intradermally migrate poorly to lymph nodes (LNs). In vitro maturation protocols generate DCs...... and PGE2-DCs, migration of type 1 DCs was strikingly impaired compared with PGE2-DCs, but only toward low concentrations of CCL21. When type 1 DCs were cultured overnight in fresh culture medium (reducing autocrine CCL19 levels), a rescuing effect was observed on migration toward low concentrations of CCL...

  5. CXCL12 is essential for migration of activated Langerhans cells from epidermis to dermis.

    Science.gov (United States)

    Ouwehand, Krista; Santegoets, Saskia J A M; Bruynzeel, Derk P; Scheper, Rik J; de Gruijl, Tanja D; Gibbs, Susan

    2008-11-01

    The initial step in Langerhans cell (LC) migration from the epidermis to the lymph node involves migration of maturing LC into the dermis. Here, we investigated the migration of LC out of the epidermis after exposure of the skin to contact allergens. Ex vivo intact human skin, epidermal sheets, and LC derived from the MUTZ-3 cell line (MUTZ-LC) were used to determine whether dermal fibroblasts play a role in mediating LC migration towards the dermis. Exposure of epidermal sheets or MUTZ-LC to allergens (nickel sulphate, 2,4-dinitrochlorobenzene, and cinnamaldehyde) or a cytokine maturation cocktail resulted in LC migration towards dermal fibroblasts. This was due to upregulation of CXCR4 on maturing LC and secretion of CXCL12/stromal derived factor-1 chemokine by fibroblasts. Neutralizing antibodies to either CXCL12 or CXCR4 completely blocked migration. Injection of CXCL12 neutralizing antibodies into intact human skin totally inhibited LC migration into the dermis. In contrast, neutralizing antibodies to CCL19/CCL21 did not inhibit migration into the dermis. We describe a novel and essential role of dermis-derived CXCL12 in initiating migration of maturing human LC to the dermis thus permitting their further journey to the draining lymph nodes.

  6. TAZ Mediates Lysophosphatidic Acid-Induced Migration and Proliferation of Epithelial Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Geun Ok Jeong

    2013-07-01

    Full Text Available Background: Transcriptional co-activator with PDZ-binding motif (TAZ, a downstream effector of the Hippo pathway, has been reported to regulate organ size, tissue homeostasis, and tumorigenesis by acting as a transcriptional co-activator. Lysophosphatidic acid (LPA is a bioactive lipid implicated in tumorigenesis and metastasis of ovarian cancer through activation of G protein-coupled receptors. However, the involvement of TAZ in LPA-induced tumorigenesis of ovarian cancer has not been elucidated. Methods: In order to demonstrate the role of TAZ in LPA-stimulated tumorigenesis, the effects of LPA on TAZ expression and cell migration were determined by Western blotting and chemotaxis analyses in R182 human epithelial ovarian cancer cells. Results and Conclusion: Treatment of R182 cells with the LPA receptor inhibitor Ki16425 blocked LPA-induced cell migration. In addition, transfection of R182 cells with small interfering RNA specific for LPA receptor 1 resulted in abrogation of LPA-stimulated cell migration. LPA induced phosphorylation of ERK and p38 MAP kinase in R182 cells and pretreatment of cells with the MEK-ERK pathway inhibitor U0126, but not the p38 MAPK inhibitor SB202190, resulted in abrogation of LPA-induced cell migration. Pretreatment of R182 cells with U0126 attenuated LPA-induced mRNA levels of TAZ and its transcriptional target genes, such as CTGF and CYR61, without affecting phosphorylation level of YAP. These results suggest that MEK-ERK pathway plays a key role in LPA-induced cell migration and mRNA expression of TAZ in R182 cells, without affecting stability of TAZ protein. In addition, small interfering RNA-mediated silencing of TAZ expression attenuated LPA-stimulated migration of R182 cells. These results suggest that TAZ plays a key role in LPA-stimulated migration of epithelial ovarian cancer cells.

  7. Computational models reveal a passive mechanism for cell migration in the crypt.

    Directory of Open Access Journals (Sweden)

    Sara-Jane Dunn

    Full Text Available Cell migration in the intestinal crypt is essential for the regular renewal of the epithelium, and the continued upward movement of cells is a key characteristic of healthy crypt dynamics. However, the driving force behind this migration is unknown. Possibilities include mitotic pressure, active movement driven by motility cues, or negative pressure arising from cell loss at the crypt collar. It is possible that a combination of factors together coordinate migration. Here, three different computational models are used to provide insight into the mechanisms that underpin cell movement in the crypt, by examining the consequence of eliminating cell division on cell movement. Computational simulations agree with existing experimental results, confirming that migration can continue in the absence of mitosis. Importantly, however, simulations allow us to infer mechanisms that are sufficient to generate cell movement, which is not possible through experimental observation alone. The results produced by the three models agree and suggest that cell loss due to apoptosis and extrusion at the crypt collar relieves cell compression below, allowing cells to expand and move upwards. This finding suggests that future experiments should focus on the role of apoptosis and cell extrusion in controlling cell migration in the crypt.

  8. Astrocytes from the brain microenvironment alter migration and morphology of metastatic breast cancer cells.

    Science.gov (United States)

    Shumakovich, Marina A; Mencio, Caitlin P; Siglin, Jonathan S; Moriarty, Rebecca A; Geller, Herbert M; Stroka, Kimberly M

    2017-08-09

    Tumor cell metastasis to the brain involves cell migration through biochemically and physically complex microenvironments at the blood-brain barrier (BBB). The current understanding of tumor cell migration across the BBB is limited. We hypothesize that an interplay between biochemical cues and physical cues at the BBB affects the mechanisms of brain metastasis. We found that astrocyte conditioned medium (ACM) applied directly to tumor cells increased tumor cell velocity, induced elongation, and promoted actin stress fiber organization. Notably, treatment of the extracellular matrix with ACM led to even more significant increases in tumor cell velocity in comparison with ACM treatment of cells directly. Furthermore, inhibiting matrix metalloproteinases in ACM reversed ACM's effect on tumor cells. The effects of ACM on tumor cell morphology and migration also depended on astrocytes' activation state. Finally, using a microfluidic device, we found that the effects of ACM were abrogated in confinement. Overall, our work demonstrates that astrocyte-secreted factors alter migration and morphology of metastatic breast tumor cells, and this effect depends on the cells' mechanical microenvironment.-Shumakovich, M. A., Mencio, C. P., Siglin, J. S., Moriarty, R. A., Geller, H. M., Stroka, K. M. Astrocytes from the brain microenvironment alter migration and morphology of metastatic breast cancer cells. © FASEB.

  9. Sphingosine-1-phosphate receptors regulate individual cell behaviours underlying the directed migration of prechordal plate progenitor cells during zebrafish gastrulation.

    Science.gov (United States)

    Kai, Masatake; Heisenberg, Carl-Philipp; Tada, Masazumi

    2008-09-01

    During vertebrate gastrulation, cells forming the prechordal plate undergo directed migration as a cohesive cluster. Recent studies revealed that E-cadherin-mediated coherence between these cells plays an important role in effective anterior migration, and that platelet-derived growth factor (Pdgf) appears to act as a guidance cue in this process. However, the mechanisms underlying this process at the individual cell level remain poorly understood. We have identified miles apart (mil) as a suppressor of defective anterior migration of the prospective prechordal plate in silberblick (slb)/wnt11 mutant embryos, in which E-cadherin-mediated coherence of cell movement is reduced. mil encodes Edg5, a sphingosine-1-phosphate (S1P) receptor belonging to a family of five G-protein-coupled receptors (S1PRs). S1P is a lipid signalling molecule that has been implicated in regulating cytoskeletal rearrangements, cell motility and cell adhesion in a variety of cell types. We examined the roles of Mil in anterior migration of prechordal plate progenitor cells and found that, in slb embryos injected with mil-MO, cells migrate with increased motility but decreased directionality, without restoring the coherence of cell migration. This indicates that prechordal plate progenitor cells can migrate effectively as individuals, as well as in a coherent cluster of cells. Moreover, we demonstrate that Mil regulates cell motility and polarisation through Pdgf and its intracellular effecter PI3K, but modulates cell coherence independently of the Pdgf/PI3K pathway, thus co-ordinating cell motility and coherence. These results suggest that the net migration of prechordal plate progenitors is determined by different parameters, including motility, persistence and coherence.

  10. Discovery of Novel Small Molecules that Activate Satellite Cell Proliferation and Enhance Repair of Damaged Muscle.

    Science.gov (United States)

    Billin, Andrew N; Bantscheff, Marcus; Drewes, Gerard; Ghidelli-Disse, Sonja; Holt, Jason A; Kramer, Henning F; McDougal, Alan J; Smalley, Terry L; Wells, Carrow I; Zuercher, William J; Henke, Brad R

    2016-02-19

    Skeletal muscle progenitor stem cells (referred to as satellite cells) represent the primary pool of stem cells in adult skeletal muscle responsible for the generation of new skeletal muscle in response to injury. Satellite cells derived from aged muscle display a significant reduction in regenerative capacity to form functional muscle. This decrease in functional recovery has been attributed to a decrease in proliferative capacity of satellite cells. Hence, agents that enhance the proliferative abilities of satellite cells may hold promise as therapies for a variety of pathological settings, including repair of injured muscle and age- or disease-associated muscle wasting. Through phenotypic screening of isolated murine satellite cells, we identified a series of 2,4-diaminopyrimidines (e.g., 2) that increased satellite cell proliferation. Importantly, compound 2 was effective in accelerating repair of damaged skeletal muscle in an in vivo mouse model of skeletal muscle injury. While these compounds were originally prepared as c-Jun N-terminal kinase 1 (JNK-1) inhibitors, structure-activity analyses indicated JNK-1 inhibition does not correlate with satellite cell activity. Screening against a broad panel of kinases did not result in identification of an obvious molecular target, so we conducted cell-based proteomics experiments in an attempt to identify the molecular target(s) responsible for the potentiation of the satellite cell proliferation. These data provide the foundation for future efforts to design improved small molecules as potential therapeutics for muscle repair and regeneration.

  11. Oxidative stress enhances Axl-mediated cell migration through an Akt1/Rac1-dependent mechanism.

    Science.gov (United States)

    Huang, Jhy-Shrian; Cho, Chun-Yu; Hong, Chih-Chen; Yan, Ming-De; Hsieh, Mao-Chih; Lay, Jong-Ding; Lai, Gi-Ming; Cheng, Ann-Lii; Chuang, Shuang-En

    2013-12-01

    Persistent oxidative stress is common in cancer cells because of abnormal generation of reactive oxygen species (ROS) and has been associated with malignant phenotypes, such as chemotherapy resistance and metastasis. Both overexpression of Axl and abnormal ROS elevation have been linked to cell transformation and increased cell migration. However, the relationship between Axl and ROS in malignant cell migration has not been previously evaluated. Using an in vitro human lung cancer model, we examined the redox state of lung adenocarcinoma cell lines of low metastatic (CL1-0) and high metastatic (CL1-5) potentials. Here we report that Axl activation elicits ROS accumulation through the oxidase-coupled small GTPase Rac1. We also observed that oxidative stress could activate Axl phosphorylation to synergistically enhance cell migration. Further, Axl signaling activated by H2O2 treatment results in enhancement of cell migration via a PI3K/Akt-dependent pathway. The kinase activity of Axl is required for the Axl-mediated cell migration and prolongs the half-life of phospho-Akt under oxidative stress. Finally, downregulation of Akt1, but not Akt2, by RNAi in Axl-overexpressing cells inhibits the amount of activated Rac1 and the ability to migrate induced by H2O2 treatment. Together, these results show that a novel Axl-signaling cascade induced by H2O2 treatment triggers cell migration through the PI3K/Akt1/Rac1 pathway. Elucidation of redox regulation in Axl-related malignant migration may provide new molecular insights into the mechanisms underlying tumor progression.

  12. Brief Report: Robo1 Regulates the Migration of Human Subventricular Zone Neural Progenitor Cells During Development.

    Science.gov (United States)

    Guerrero-Cazares, Hugo; Lavell, Emily; Chen, Linda; Schiapparelli, Paula; Lara-Velazquez, Montserrat; Capilla-Gonzalez, Vivian; Clements, Anna Christina; Drummond, Gabrielle; Noiman, Liron; Thaler, Katrina; Burke, Anne; Quiñones-Hinojosa, Alfredo

    2017-07-01

    Human neural progenitor cell (NPC) migration within the subventricular zone (SVZ) of the lateral ganglionic eminence is an active process throughout early brain development. The migration of human NPCs from the SVZ to the olfactory bulb during fetal stages resembles what occurs in adult rodents. As the human brain develops during infancy, this migratory stream is drastically reduced in cell number and becomes barely evident in adults. The mechanisms regulating human NPC migration are unknown. The Slit-Robo signaling pathway has been defined as a chemorepulsive cue involved in axon guidance and neuroblast migration in rodents. Slit and Robo proteins expressed in the rodent brain help guide neuroblast migration from the SVZ through the rostral migratory stream to the olfactory bulb. Here, we present the first study on the role that Slit and Robo proteins play in human-derived fetal neural progenitor cell migration (hfNPC). We describe that Robo1 and Robo2 isoforms are expressed in the human fetal SVZ. Furthermore, we demonstrate that Slit2 is able to induce a chemorepellent effect on the migration of hfNPCs derived from the human fetal SVZ. In addition, when Robo1 expression is inhibited, hfNPCs are unable to migrate to the olfactory bulb of mice when injected in the anterior SVZ. Our findings indicate that the migration of human NPCs from the SVZ is partially regulated by the Slit-Robo axis. This pathway could be regulated to direct the migration of NPCs in human endogenous neural cell therapy. Stem Cells 2017;35:1860-1865. © 2017 AlphaMed Press.

  13. Chemoattractant signaling between tumor cells and macrophages regulates cancer cell migration, metastasis and neovascularization.

    Directory of Open Access Journals (Sweden)

    Chad E Green

    Full Text Available Tumor-associated macrophages are known to influence cancer progression by modulation of immune function, angiogenesis, and cell metastasis, however, little is known about the chemokine signaling networks that regulate this process. Utilizing CT26 colon cancer cells and RAW 264.7 macrophages as a model cellular system, we demonstrate that treatment of CT26 cells with RAW 264.7 conditioned medium induces cell migration, invasion and metastasis. Inflammatory gene microarray analysis indicated CT26-stimulated RAW 264.7 macrophages upregulate SDF-1alpha and VEGF, and that these cytokines contribute to CT26 migration in vitro. RAW 264.7 macrophages also showed a robust chemotactic response towards CT26-derived chemokines. In particular, microarray analysis and functional testing revealed CSF-1 as the major chemoattractant for RAW 264.7 macrophages. Interestingly, in the chick CAM model of cancer progression, RAW 264.7 macrophages localized specifically to the tumor periphery where they were found to increase CT26 tumor growth, microvascular density, vascular disruption, and lung metastasis, suggesting these cells home to actively invading areas of the tumor, but not the hypoxic core of the tumor mass. In support of these findings, hypoxic conditions down regulated CSF-1 production in several tumor cell lines and decreased RAW 264.7 macrophage migration in vitro. Together our findings suggest a model where normoxic tumor cells release CSF-1 to recruit macrophages to the tumor periphery where they secrete motility and angiogenic factors that facilitate tumor cell invasion and metastasis.

  14. The Hippo pathway polarizes the actin cytoskeleton during collective migration of Drosophila border cells.

    Science.gov (United States)

    Lucas, Eliana P; Khanal, Ichha; Gaspar, Pedro; Fletcher, Georgina C; Polesello, Cedric; Tapon, Nicolas; Thompson, Barry J

    2013-06-10

    Collective migration of Drosophila border cells depends on a dynamic actin cytoskeleton that is highly polarized such that it concentrates around the outer rim of the migrating cluster of cells. How the actin cytoskeleton becomes polarized in these cells to enable collective movement remains unknown. Here we show that the Hippo signaling pathway links determinants of cell polarity to polarization of the actin cytoskeleton in border cells. Upstream Hippo pathway components localize to contacts between border cells inside the cluster and signal through the Hippo and Warts kinases to polarize actin and promote border cell migration. Phosphorylation of the transcriptional coactivator Yorkie (Yki)/YAP by Warts does not mediate the function of this pathway in promoting border cell migration, but rather provides negative feedback to limit the speed of migration. Instead, Warts phosphorylates and inhibits the actin regulator Ena to activate F-actin Capping protein activity on inner membranes and thereby restricts F-actin polymerization mainly to the outer rim of the migrating cluster.

  15. Patterning of Endothelial Cells and Mesenchymal Stem Cells by Laser-Assisted Bioprinting to Study Cell Migration

    Directory of Open Access Journals (Sweden)

    Jean-Michel Bourget

    2016-01-01

    Full Text Available Tissue engineering of large organs is currently limited by the lack of potent vascularization in vitro. Tissue-engineered bone grafts can be prevascularized in vitro using endothelial cells (ECs. The microvascular network architecture could be controlled by printing ECs following a specific pattern. Using laser-assisted bioprinting, we investigated the effect of distance between printed cell islets and the influence of coprinted mesenchymal cells on migration. When printed alone, ECs spread out evenly on the collagen hydrogel, regardless of the distance between cell islets. However, when printed in coculture with mesenchymal cells by laser-assisted bioprinting, they remained in the printed area. Therefore, the presence of mesenchymal cell is mandatory in order to create a pattern that will be conserved over time. This work describes an interesting approach to study cell migration that could be reproduced to study the effect of trophic factors.

  16. Patterning of Endothelial Cells and Mesenchymal Stem Cells by Laser-Assisted Bioprinting to Study Cell Migration

    Science.gov (United States)

    Medina, Manuela; Rémy, Murielle; Thébaud, Noélie Brunehilde; Bareille, Reine; Chassande, Olivier; Amédée, Joëlle; Catros, Sylvain

    2016-01-01

    Tissue engineering of large organs is currently limited by the lack of potent vascularization in vitro. Tissue-engineered bone grafts can be prevascularized in vitro using endothelial cells (ECs). The microvascular network architecture could be controlled by printing ECs following a specific pattern. Using laser-assisted bioprinting, we investigated the effect of distance between printed cell islets and the influence of coprinted mesenchymal cells on migration. When printed alone, ECs spread out evenly on the collagen hydrogel, regardless of the distance between cell islets. However, when printed in coculture with mesenchymal cells by laser-assisted bioprinting, they remained in the printed area. Therefore, the presence of mesenchymal cell is mandatory in order to create a pattern that will be conserved over time. This work describes an interesting approach to study cell migration that could be reproduced to study the effect of trophic factors. PMID:27833916

  17. Effect of epidermal growth factor on the migration of neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Faliang Duan; Guoping Yang; Junwu Wei; Jinglei Wu

    2006-01-01

    BACKGROUND:Recently,researches on neural stem cells(NSCs)are focus on differentiation and migration of stem cells.How to regulate and control differentiation and migration of NSCs based on human wills is still a hot topic.OBJECTIVE:To investigate the effct of epidermal growth factor (EGF) on the migration and proliferation of NSCs and analyze duration of the effect.DESIGN:Contrast study based on cells.SETFING:Department of Neurological Surgery,the First Hospital of Wuhan.MATERIALS:Healthy SD rats aged 13-14 embryonic days.EGF(Sigma Company).METHODS:The experiment was carried out in the Animal Laboratory of Experimental Center Affiliated to the First Hospital of Wuhan from October 2004 to July 2006.NSCs selected from embryonic striatum of rats with 13-14 embryonic days were cultured;7 days later,suspended neural sphere was used to make simple cell suspension and cultured once more.Then,DMEM-F12+20 μg/L EGF was added into culture medium;14 days latar.the rats were divided into experimental group and control group.Rats in the experimental group were cultured with the same medium mentioned above;however, rats in the control group were cultured with only DMEM-F12.Migration of cells was observed under microscope every day.MAIN OUTCOME MEASURES:NSCs migration in both experimental group and control group.RESULTS:Cell spheres in primary culture were NSCs.In addition,14 days later,proliferation of stem cells were observed remarkably in EGF culture.and size of cell sphere was about that of 100 cells.In exparimental group.proliferation of cell sphere was slow down on the 14th culture day,and apophysis was erupted to neighbor cell sphere.Moreover,NSCs migrated from big cell sphere to small cell sphere during 14-17 culture days.and then,cell migration was disappeared at 17 days after culture.In control group.cell migration was not observed.CONCLUSION:EGF can induce proliferation and migration of NSCs during a special time(14-17 days).However,NSCs do not immigrate over the

  18. The Maf factor Traffic jam both enables and inhibits collective cell migration in Drosophila oogenesis.

    Science.gov (United States)

    Gunawan, Felix; Arandjelovic, Mimi; Godt, Dorothea

    2013-07-01

    Border cell cluster (BCC) migration in the Drosophila ovary is an excellent system to study the gene regulatory network that enables collective cell migration. Here, we identify the large Maf transcription factor Traffic jam (Tj) as an important regulator of BCC migration. Tj has a multifaceted impact on the known core cascade that enables BCC motility, consisting of the Jak/Stat signaling pathway, the C/EBP factor Slow border cells (Slbo), and the downstream effector DE-cadherin (DEcad). The initiation of BCC migration coincides with a Slbo-dependent decrease in Tj expression. This reduction of Tj is required for normal BCC motility, as high Tj expression strongly impedes migration. At high concentration, Tj has a tripartite negative effect on the core pathway: a decrease in Slbo, an increase in the Jak/Stat inhibitor Socs36E, and a Slbo-independent reduction of DEcad. However, maintenance of a low expression level of Tj in the BCC during migration is equally important, as loss of tj function also results in a significant delay in migration concomitant with a reduction of Slbo and consequently of DEcad. Taken together, we conclude that the regulatory feedback loop between Tj and Slbo is necessary for achieving the correct activity levels of migration-regulating factors to ensure proper BCC motility.

  19. Rb1 gene inactivation expands satellite cell and postnatal myoblast pools.

    Science.gov (United States)

    Hosoyama, Tohru; Nishijo, Koichi; Prajapati, Suresh I; Li, Guangheng; Keller, Charles

    2011-06-03

    Satellite cells are well known as a postnatal skeletal muscle stem cell reservoir that under injury conditions participate in repair. However, mechanisms controlling satellite cell quiescence and activation are the topic of ongoing inquiry by many laboratories. In this study, we investigated whether loss of the cell cycle regulatory factor, pRb, is associated with the re-entry of quiescent satellite cells into replication and subsequent stem cell expansion. By ablation of Rb1 using a Pax7CreER,Rb1 conditional mouse line, satellite cell number was increased 5-fold over 6 months. Furthermore, myoblasts originating from satellite cells lacking Rb1 were also increased 3-fold over 6 months, while terminal differentiation was greatly diminished. Similarly, Pax7CreER,Rb1 mice exhibited muscle fiber hypotrophy in vivo under steady state conditions as well as a delay of muscle regeneration following cardiotoxin-mediated injury. These results suggest that cell cycle re-entry of quiescent satellite cells is accelerated by lack of Rb1, resulting in the expansion of both satellite cells and their progeny in adolescent muscle. Conversely, that sustained Rb1 loss in the satellite cell lineage causes a deficit of muscle fiber formation. However, we also show that pharmacological inhibition of protein phosphatase 1 activity, which will result in pRb inactivation accelerates satellite cell activation and/or expansion in a transient manner. Together, our results raise the possibility that reversible pRb inactivation in satellite cells and inhibition of protein phosphorylation may provide a new therapeutic tool for muscle atrophy by short term expansion of the muscle stem cells and myoblast pool.

  20. Effect of chymotrypsin C and related proteins on pancreatic cancer cell migration

    Institute of Scientific and Technical Information of China (English)

    Haibo Wang; Wei Sha; Zhixue Liu; Cheng-Wu Chi

    2011-01-01

    Pancreatic cancer is a malignant cancer with a bigh mortality rate. The amount of chymotrypsin C in pancreatic cancer cells is only 20% of that found in normal cells.Chymotrypsin C has been reported to be involved in cancer cell apoptosis, but its effect on pancreatic cancer cell migration is unclear. We performed cell migration scratch assays and Transwell experiments, and found that cell migration ability was downregulated in pancreatic cancer Aspc-1 cells that overexpressed chymotrypsin C, whereas the cell migration ability was upregulated in Aspc-1 cells in which chymotrypsin C was suppressed. Two-dimensional fluorescence differential in gel electrophoresis/mass spectrometry method was used to identify the proteins that were differentially expressed in Aspc-1 cells that were transfected with plasmids to induce either overexpression or suppressed expression of chymotrypsin C. Among 26 identified differential proteins, cytokeratin 18 was most obviously correlated with chymotrypsin C expression. Cytokeratin 18 is expressed in developmental tissues in early stages of cancer,and is highly expressed in most carcinomas. We speculated that chymotrypsin C might regulate pancreatic cancer cell migration in relation to cytokeratin 18 expression.

  1. Inhibitory effect of blue light emitting diode on migration and invasion of cancer cells.

    Science.gov (United States)

    Oh, Phil-Sun; Kim, Hyun-Soo; Kim, Eun-Mi; Hwang, Hyosook; Ryu, Hyang Hwa; Lim, SeokTae; Sohn, Myung-Hee; Jeong, Hwan-Jeong

    2017-12-01

    The aim of this study was to determine the effects and molecular mechanism of blue light emitting diode (LED) in tumor cells. A migration and invasion assay for the metastatic behavior of mouse colon cancer CT-26 and human fibrosarcoma HT-1080 cells was performed. Cancer cell migration-related proteins were identified by obtaining a 2-dimensional gel electrophoresis (2-DE) in total cellular protein profile of blue LED-irradiated cancer cells, followed by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis of proteins. Protein levels were examined by immunoblotting. Irradiation with blue LED inhibited CT-26 and HT-1080 cell migration and invasion. The anti-metastatic effects of blue LED irradiation were associated with inhibition of matrix metalloproteinase (MMP)-2 and MMP-9 expression. P38 MAPK phosphorylation was increased in blue LED-irradiated CT-26 and HT-1080 cells, but was inhibited after pretreatment with SB203580, a specific inhibitor of p38 MAPK. Inhibition of p38 MAPK phosphorylation by SB203580 treatment increased number of migratory cancer cells in CT-26 and HT-1080 cells, indicating that blue LED irradiation inhibited cancer cell migration via phosphorylation of p38 MAPK. Additionally blue LED irradiation of mice injected with CT-26 cells expressing luciferase decreased early stage lung metastasis compared to untreated control mice. These results indicate that blue LED irradiation inhibits cancer cell migration and invasion in vitro and in vivo. © 2017 Wiley Periodicals, Inc.

  2. Ring-Shaped Microlanes and Chemical Barriers as a Platform for Probing Single-Cell Migration

    Science.gov (United States)

    Schreiber, Christoph; Segerer, Felix J.; Wagner, Ernst; Roidl, Andreas; Rädler, Joachim O.

    2016-01-01

    Quantification and discrimination of pharmaceutical and disease-related effects on cell migration requires detailed characterization of single-cell motility. In this context, micropatterned substrates that constrain cells within defined geometries facilitate quantitative readout of locomotion. Here, we study quasi-one-dimensional cell migration in ring-shaped microlanes. We observe bimodal behavior in form of alternating states of directional migration (run state) and reorientation (rest state). Both states show exponential lifetime distributions with characteristic persistence times, which, together with the cell velocity in the run state, provide a set of parameters that succinctly describe cell motion. By introducing PEGylated barriers of different widths into the lane, we extend this description by quantifying the effects of abrupt changes in substrate chemistry on migrating cells. The transit probability decreases exponentially as a function of barrier width, thus specifying a characteristic penetration depth of the leading lamellipodia. Applying this fingerprint-like characterization of cell motion, we compare different cell lines, and demonstrate that the cancer drug candidate salinomycin affects transit probability and resting time, but not run time or run velocity. Hence, the presented assay allows to assess multiple migration-related parameters, permits detailed characterization of cell motility, and has potential applications in cell biology and advanced drug screening. PMID:27242099

  3. In-vivo cell tracking to quantify endothelial cell migration during zebrafish angiogenesis

    Science.gov (United States)

    Menon, Prahlad G.; Rochon, Elizabeth R.; Roman, Beth L.

    2016-03-01

    The mechanism of endothelial cell migration as individual cells or collectively while remaining an integral component of a functional blood vessel has not been well characterized. In this study, our overarching goal is to define an image processing workflow to facilitate quantification of how endothelial cells within the first aortic arch and are proximal to the zebrafish heart behave in response to the onset of flow (i.e. onset of heart beating). Endothelial cell imaging was conducted at this developmental time-point i.e. ~24-28 hours post fertilization (hpf) when flow first begins, using 3D+time two-photon confocal microscopy of a live, wild-type, transgenic, zebrafish expressing green fluorescent protein (GFP) in endothelial cell nuclei. An image processing pipeline comprised of image signal enhancement, median filtering for speckle noise reduction, automated identification of the nuclei positions, extraction of the relative movement of nuclei between consecutive time instances, and finally tracking of nuclei, was designed for achieving the tracking of endothelial cell nuclei and the identification of their movement towards or away from the heart. Pilot results lead to a hypothesis that upon the onset of heart beat and blood flow, endothelial cells migrate collectively towards the heart (by 21.51+/-10.35 μm) in opposition to blood flow (i.e. subtending 142.170+/-21.170 with the flow direction).

  4. Subversion of cell-autonomous immunity and cell migration by Legionella pneumophila effectors

    Directory of Open Access Journals (Sweden)

    Sylvia eSimon

    2015-09-01

    Full Text Available Bacteria trigger host defense and inflammatory processes such as cytokine production, pyroptosis and the chemotactic migration of immune cells towards the source of infection. However, a number of pathogens interfere with these immune functions by producing specific so-called effector proteins, which are delivered to host cells via dedicated secretion systems. Air-borne Legionella pneumophila bacteria trigger an acute and potential fatal inflammation in the lung termed Legionnaires’ disease. The opportunistic pathogen L. pneumophila is a natural parasite of free-living amoebae, but also replicates in alveolar macrophages and accidentally infects humans. The bacteria employ the Icm/Dot type IV secretion system and as many as 300 different effector proteins to govern host cell interactions and establish in phagocytes an intracellular replication niche, the Legionella-containing vacuole. Some Icm/Dot-translocated effector proteins target cell autonomous immunity or cell migration, i.e. they interfere with (i endocytic, secretory or retrograde vesicle trafficking pathways, (ii organelle or cell motility, (iii the inflammasome and programmed cell death, or (iv the transcription factor NF-κB. Here we review recent mechanistic insights into the subversion of cellular immune functions by L. pneumophila.

  5. Loss of myoferlin redirects breast cancer cell motility towards collective migration.

    Directory of Open Access Journals (Sweden)

    Leonithas I Volakis

    Full Text Available Cell migration plays a central role in the invasion and metastasis of tumors. As cells leave the primary tumor, they undergo an epithelial to mesenchymal transition (EMT and migrate as single cells. Epithelial tumor cells may also migrate in a highly directional manner as a collective group in some settings. We previously discovered that myoferlin (MYOF is overexpressed in breast cancer cells and depletion of MYOF results in a mesenchymal to epithelial transition (MET and reduced invasion through extracellular matrix (ECM. However, the biomechanical mechanisms governing cell motility during MYOF depletion are poorly understood. We first demonstrated that lentivirus-driven shRNA-induced MYOF loss in MDA-MB-231 breast cancer cells (MDA-231(MYOF-KD leads to an epithelial morphology compared to the mesenchymal morphology observed in control (MDA-231(LTVC and wild-type cells. Knockdown of MYOF led to significant reductions in cell migration velocity and MDA-231(MYOF-KD cells migrated directionally and collectively, while MDA-231(LTVC cells exhibited single cell migration. Decreased migration velocity and collective migration were accompanied by significant changes in cell mechanics. MDA-231(MYOF-KD cells exhibited a 2-fold decrease in cell stiffness, a 2-fold increase in cell-substrate adhesion and a 1.5-fold decrease in traction force generation. In vivo studies demonstrated that when immunocompromised mice were implanted with MDA-231(MYOF-KD cells, tumors were smaller and demonstrated lower tumor burden. Moreover, MDA-231(MYOF-KD tumors were highly circularized and did not invade locally into the adventia in contrast to MDA-231(LTVC-injected animals. Thus MYOF loss is associated with a change in tumor formation in xenografts and leads to smaller, less invasive tumors. These data indicate that MYOF, a previously unrecognized protein in cancer, is involved in MDA-MB-231 cell migration and contributes to biomechanical alterations. Our results indicate

  6. Transforming potential and matrix stiffness co-regulate confinement sensitivity of tumor cell migration

    Science.gov (United States)

    Pathak, Amit

    2013-01-01

    It is now well established that tumor cell invasion through tissue is strongly regulated by the microstructural and mechanical properties of the extracellular matrix (ECM). However, it remains unclear how these physical microenvironmental inputs are jointly processed with oncogenic lesions to drive invasion. In this study, we address this open question by combining a microfabricated polyacrylamide channel (μPAC) platform that enables independent control of ECM stiffness and confinement with an isogenically-matched breast tumor progression series in which the oncogenes ErbB2 and 14-3-3ζ are overexpressed independently or in tandem. We find that increasing channel confinement and overexpressing ErbB2 both promote cell migration to a similar degree when other parameters are kept constant. In contrast, 14-3-3ζ overexpression slows migration speed, and does so in a fashion that dwarfs effects of ECM confinement and stiffness. We also find that ECM stiffness dramatically enhances cell motility when combined with ErbB2 overexpression, demonstrating that biophysical cues and cell-intrinsic parameters promote cell invasion in an integrative manner. Morphometric analysis of cells inside the μPAC platform reveals that the rapid cell migration induced by narrow channels and ErbB2 overexpression both are accompanied by increased cell polarization. Disruption of this polarization by pharmacological inhibition of Rac GTPase phenocopies 14-3-3ζ overexpression by reducing cell polarization and slowing migration. By systematically measuring migration speed as a function of matrix stiffness and confinement, we also quantify for the first time the sensitivity of migration speed to microchannel properties and transforming potential. These results demonstrate that oncogenic lesions and ECM biophysical properties can synergistically interact to drive invasive migration, and that both inputs may act through common molecular mechanisms to enhance migration speed. PMID:23832051

  7. Expression of Rho GTPases family in melanoma cells and its influence on cytoskeleton and migration.

    Science.gov (United States)

    Wen, Si-Jian; Zhang, Wei; Ni, Na-Na; Wu, Qiong; Wang, Xiao-Po; Lin, You-Kun; Sun, Jian-Fang

    2017-05-02

    Rho GTPases family members influenced the filopodia, lamellipodia, stress fiber and adhesion plaque of melanoma cells through regulating cytoskeleton recombination. The role of Rho GTPases family in the migration and invasion of melanoma and its molecular mechanism were explored. The morphological difference between three types of melanoma cells (M14, A375 and MV3) and human melanocyte (MC) was observed by the Hoffman microscope. Cells were stained by phalloidin labeled by rhodamine. The differences between 4 types of cells in filopodia, lamellipodia, stress fiber and adhesion plaque (microfilament is the main constituent) were observed under the super-high resolution microscope. The migration ability of 4 types of cells was detected by Transwell migration assay. QPCR was used to detect the mRNA transcription level of Rho GTPases family. WB was adopted to detect the expression of RhoD and DIAPH2 proteins. There were significant differences in filopodia, lamellipodia, stress fiber and adhesion plaque between MC and 3 types of melanoma cells (M14, A375 and MV3). MC did not have stress fiber or adhesion plaque, while M14, A375 and MV3 had stress fiber and adhesion plaque. All 4 types of cells had thin and short filopodia. MV3 had fewer but thicker stress fibers than the latter two. Transwell migration test indicated the followings: M14 and A375 had a similar high migration rate; the migration rate of MV3 was slightly low; MC did not have the ability of transmembrane migration. QPCR results of Rho GTPases family in 4 types of cells showed the change corresponding to immunofluorescence. WB results showed that RhoD was barely expressed in M14, A375 or MV3. DIAPH2, the downstream effector molecule of RhoD, had the corresponding change. Rho GTPases influences the migration and invasion of melanoma cells through regulating filopodia, lamellipodia, stress fiber and adhesion plaque (microfilament is the main constituent).

  8. CD152 (CTLA-4 determines CD4 T cell migration in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Karin Knieke

    Full Text Available BACKGROUND: Migration of antigen-experienced T cells to secondary lymphoid organs and the site of antigenic-challenge is a mandatory prerequisite for the precise functioning of adaptive immune responses. The surface molecule CD152 (CTLA-4 is mostly considered as a negative regulator of T cell activation during immune responses. It is currently unknown whether CD152 can also influence chemokine-driven T cell migration. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the consequences of CD152 signaling on Th cell migration using chemotaxis assays in vitro and radioactive cell tracking in vivo. We show here that the genetic and serological inactivation of CD152 in Th1 cells reduced migration towards CCL4, CXCL12 and CCL19, but not CXCL9, in a G-protein dependent manner. In addition, retroviral transduction of CD152 cDNA into CD152 negative cells restored Th1 cell migration. Crosslinking of CD152 together with CD3 and CD28 stimulation on activated Th1 cells increased expression of the chemokine receptors CCR5 and CCR7, which in turn enhanced cell migration. Using sensitive liposome technology, we show that mature dendritic cells but not activated B cells were potent at inducing surface CD152 expression and the CD152-mediated migration-enhancing signals. Importantly, migration of CD152 positive Th1 lymphocytes in in vivo experiments increased more than 200% as compared to CD152 negative counterparts showing that indeed CD152 orchestrates specific migration of selected Th1 cells to sites of inflammation and antigenic challenge in vivo. CONCLUSIONS/SIGNIFICANCE: We show here, that CD152 signaling does not just silence cells, but selects individual ones for migration. This novel activity of CD152 adds to the already significant role of CD152 in controlling peripheral immune responses by allowing T cells to localize correctly during infection. It also suggests that interference with CD152 signaling provides a tool for altering the cellular composition at

  9. Isolation, culture and biological characteristics of multipotent porcine skeletal muscle satellite cells.

    Science.gov (United States)

    Yang, Jinjuan; Liu, Hao; Wang, Kunfu; Li, Lu; Yuan, Hongyi; Liu, Xueting; Liu, Yingjie; Guan, Weijun

    2017-03-02

    Skeletal muscle has a huge regenerative potential for postnatal muscle growth and repair, which mainly depends on a kind of muscle progenitor cell population, called satellite cell. Nowadays, the majority of satellite cells were obtained from human, mouse, rat and other animals but rarely from pig. In this article, the porcine skeletal muscle satellite cells were isolated and cultured in vitro. The expression of surface markers of satellite cells was detected by immunofluorescence and RT-PCR assays. The differentiation capacity was assessed by inducing satellite cells into adipocytes, myoblasts and osteoblasts. The results showed that satellite cells isolated from porcine tibialis anterior were subcultured up to 12 passages and were positive for Pax7, Myod, c-Met, desmin, PCNA and NANOG but were negative for Myogenin. Satellite cells were also induced to differentiate into adipocytes, osteoblasts and myoblasts, respectively. These findings indicated that porcine satellite cells possess similar biological characteristics of stem cells, which may provide theoretical basis and experimental evidence for potential therapeutic application in the treatment of dystrophic muscle and other muscle injuries.

  10. Isolation, Culture, and Immunostaining of Skeletal Muscle Myofibers from Wildtype and Nestin-GFP Mice as a Means to Analyze Satellite Cell.

    Science.gov (United States)

    Stuelsatz, Pascal; Keire, Paul; Yablonka-Reuveni, Zipora

    2017-01-01

    Multinucleated myofibers, the functional contractile units of adult skeletal muscle, harbor mononuclear Pax7(+) myogenic progenitors on their surface between the myofiber basal lamina and plasmalemma. These progenitors, known as satellite cells, are the primary myogenic stem cells in adult muscle. This chapter describes our laboratory protocols for isolating, culturing, and immunostaining intact myofibers from mouse skeletal muscle as a means for studying satellite cell dynamics. The first protocol discusses myofiber isolation from the flexor digitorum brevis (FDB) muscle. These short myofibers are plated in dishes coated with PureCol collagen (formerly known as Vitrogen) and maintained in a mitogen-poor medium (± supplemental growth factors). Employing such conditions, satellite cells remain at the surface of the parent myofiber while synchronously undergoing a limited number of proliferative cycles and rapidly differentiate. The second protocol discusses the isolation of longer myofibers from the extensor digitorum longus (EDL) muscle. These EDL myofibers are routinely plated individually as adherent myofibers in wells coated with Matrigel and maintained in a mitogen-rich medium, conditions in which satellite cells migrate away from the parent myofiber, proliferate extensively, and generate numerous differentiating progeny. Alternatively, these EDL myofibers can be plated as non-adherent myofibers in uncoated wells and maintained in a mitogen-poor medium (± supplemental growth factors), conditions that retain satellite cell progeny at the myofiber niche similar to the FDB myofiber cultures. However, the adherent myofiber format is our preferred choice for monitoring satellite cells in freshly isolated (Time 0) myofibers. We conclude this chapter by promoting the Nestin-GFP transgenic mouse as an efficient tool for direct analysis of satellite cells in isolated myofibers. While satellite cells have been often detected by their expression of the Pax7 protein or

  11. Tipping the balance: robustness of tip cell selection, migration and fusion in angiogenesis.

    Directory of Open Access Journals (Sweden)

    Katie Bentley

    2009-10-01

    Full Text Available Vascular abnormalities contribute to many diseases such as cancer and diabetic retinopathy. In angiogenesis new blood vessels, headed by a migrating tip cell, sprout from pre-existing vessels in response to signals, e.g., vascular endothelial growth factor (VEGF. Tip cells meet and fuse (anastomosis to form blood-flow supporting loops. Tip cell selection is achieved by Dll4-Notch mediated lateral inhibition resulting, under normal conditions, in an interleaved arrangement of tip and non-migrating stalk cells. Previously, we showed that the increased VEGF levels found in many diseases can cause the delayed negative feedback of lateral inhibition to produce abnormal oscillations of tip/stalk cell fates. Here we describe the development and implementation of a novel physics-based hierarchical agent model, tightly coupled to in vivo data, to explore the system dynamics as perpetual lateral inhibition combines with tip cell migration and fusion. We explore the tipping point between normal and abnormal sprouting as VEGF increases. A novel filopodia-adhesion driven migration mechanism is presented and validated against in vivo data. Due to the unique feature of ongoing lateral inhibition, 'stabilised' tip/stalk cell patterns show sensitivity to the formation of new cell-cell junctions during fusion: we predict cell fates can reverse. The fusing tip cells become inhibited and neighbouring stalk cells flip fate, recursively providing new tip cells. Junction size emerges as a key factor in establishing a stable tip/stalk pattern. Cell-cell junctions elongate as tip cells migrate, which is shown to provide positive feedback to lateral inhibition, causing it to be more susceptible to pathological oscillations. Importantly, down-regulation of the migratory pathway alone is shown to be sufficient to rescue the sprouting system from oscillation and restore stability. Thus we suggest the use of migration inhibitors as therapeutic agents for vascular

  12. Chronic toluene exposure induces cell proliferation in the mice SVZ but not migration through the RMS.

    Science.gov (United States)

    Franco, Ireri; Valdez-Tapia, Mariana; Sanchez-Serrano, Sinthia L; Cruz, Silvia L; Lamas, Monica

    2014-07-11

    Abuse of toluene-containing inhalants is associated to various cognitive impairments that have been partly associated to deviation of the hippocampal neurogenesis processes during adulthood. In the present study we analyzed the effect of chronic toluene exposure (6000ppm) on cell proliferation and migration in the other selected area of the rodent brain where neurogenesis persist throughout adulthood, the subventricular zone of the lateral ventricle (SVZ). We used an anti-Ki67 antibody to evaluate SVZ cell proliferation, BrdU to evaluate cell survival and double-staining with BrdU and the migration marker doublecortin (DCX) to evaluate migration, by immunofluorescence 2h, 1, 5, 10 or 15 days after 20 sessions of toluene exposure. We found that toluene induced an initial burst of cell proliferation in the SVZ but not a significant increase in migration toward the rostral migratory stream (RMS) or the number of cells that migrate to the olfactory bulb. In addition, we detected a small number of new migrating cells in the corpus callosum and striatum of control mice that was similar in toluene-exposed brains. These results may underline the homeostatic capabilities of the populations of dividing cells, previously demonstrated using other drugs of abuse and demonstrate that toluene misuse can alter cellular proliferation in the postnatal brain. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Effects of arecoline on cell growth, migration, and differentiation in cementoblasts

    Directory of Open Access Journals (Sweden)

    Yi-Juai Chen

    2015-12-01

    Conclusion: Taken together, these results suggest that arecoline could inhibit cell growth, migration, and differentiation in cementoblasts. Areca quid chewers might be more susceptible to the destruction of periodontium and less responsive to regenerative procedure during periodontal therapy.

  14. Endocytosis regulates cell soma translocation and the distribution of adhesion proteins in migrating neurons.

    Directory of Open Access Journals (Sweden)

    Jennifer C Shieh

    Full Text Available Newborn neurons migrate from their birthplace to their final location to form a properly functioning nervous system. During these movements, young neurons must attach and subsequently detach from their substrate to facilitate migration, but little is known about the mechanisms cells use to release their attachments. We show that the machinery for clathrin-mediated endocytosis is positioned to regulate the distribution of adhesion proteins in a subcellular region just proximal to the neuronal cell body. Inhibiting clathrin or dynamin function impedes the movement of migrating neurons both in vitro and in vivo. Inhibiting dynamin function in vitro shifts the distribution of adhesion proteins to the rear of the cell. These results suggest that endocytosis may play a critical role in regulating substrate detachment to enable cell body translocation in migrating neurons.

  15. Protein kinase C, focal adhesions and the regulation of cell migration

    DEFF Research Database (Denmark)

    Fogh, Betina S; Multhaupt, Hinke A B; Couchman, John Robert

    2014-01-01

    Cell adhesion to extracellular matrix is a complex process involving protrusive activity driven by the actin cytoskeleton, engagement of specific receptors, followed by signaling and cytoskeletal organization. Thereafter, contractile and endocytic/recycling activities may facilitate migration...

  16. Satellite Cells Contribution to Exercise Mediated Muscle Hypertrophy and Repair

    Science.gov (United States)

    Bazgir, Behzad; Fathi, Rouhollah; Rezazadeh Valojerdi, Mojtaba; Mozdziak, Paul; Asgari, Alireza

    2017-01-01

    Satellite cells (SCs) are the most abundant skeletal muscle stem cells. They are widely recognized for their contributions to maintenance of muscle mass, regeneration and hypertrophy during the human life span. These cells are good candidates for cell therapy due to their self-renewal capabilities and presence in an undifferentiated form. Presently, a significant gap exists between our knowledge of SCs behavior and their application as a means for human skeletal muscle tissue repair and regeneration. Both physiological and pathological stimuli potentially affect SCs activation, proliferation, and terminal differentiation the former category being the focus of this article. Activation of SCs occurs following exercise, post-training micro-injuries, and electrical stimulation. Exercise, as a potent and natural stimulus, is at the center of numerous studies on SC activation and relevant fields. According to research, different exercise modalities end with various effects. This review article attempts to picture the state of the art of the SCs life span and their engagement in muscle regeneration and hypertrophy in exercise. PMID:28042532

  17. Satellite Cells Contribution to Exercise Mediated Muscle Hypertrophy and Repair

    Directory of Open Access Journals (Sweden)

    Behzad Bazgir

    2016-10-01

    Full Text Available Satellite cells (SCs are the most abundant skeletal muscle stem cells. They are widely recognized for their contributions to maintenance of muscle mass, regeneration and hypertrophy during the human life span. These cells are good candidates for cell therapy due to their self-renewal capabilities and presence in an undifferentiated form. Presently, a significant gap exists between our knowledge of SCs behavior and their application as a means for human skeletal muscle tissue repair and regeneration. Both physiological and pathological stimuli potentially affect SCs activation, proliferation, and terminal differentiation - the former category being the focus of this article. Activation of SCs occurs following exercise, post-training micro-injuries, and electrical stimulation. Exercise, as a potent and natural stimulus, is at the center of numerous studies on SC activation and relevant fields. According to research, different exercise modalities end with various effects. This review article attempts to picture the state of the art of the SCs life span and their engagement in muscle regeneration and hypertrophy in exercise.

  18. XB130 translocation to microfilamentous structures mediates NNK-induced migration of human bronchial epithelial cells.

    Science.gov (United States)

    Wu, Qifei; Nadesalingam, Jeya; Moodley, Serisha; Bai, Xiaohui; Liu, Mingyao

    2015-07-20

    Cigarette smoking contributes to the pathogenesis of chronic obstructive pulmonary disease and lung cancer. Nicotine-derived nitrosamine ketone (NNK) is the most potent carcinogen among cigarette smoking components, and is known to enhance migration of cancer cells. However, the effect of NNK on normal human bronchial epithelial cells is not well studied. XB130 is a member of actin filament associated protein family and is involved in cell morphology changes, cytoskeletal rearrangement and outgrowth formation, as well as cell migration. We hypothesized that XB130 mediates NNK-induced migration of normal human bronchial epithelial cells. Our results showed that, after NNK stimulation, XB130 was translocated to the cell periphery and enriched in cell motility-associated structures, such as lamellipodia, in normal human bronchial epithelial BEAS2B cells. Moreover, overexpression of XB130 significantly enhanced NNK-induced migration, which requires both the N- and C-termini of XB130. Overexpression of XB130 enhanced NNK-induced protein tyrosine phosphorylation and promoted matrix metalloproteinase-14 translocation to cell motility-associated cellular structures after NNK stimulation. XB130-mediated NNK-induced cell migration may contribute to airway epithelial repair; however, it may also be involved in cigarette smoking-related chronic obstructive pulmonary disease and lung cancer.

  19. B cells within germinal centers migrate preferentially from dark to light zone.

    Science.gov (United States)

    Beltman, Joost B; Allen, Christopher D C; Cyster, Jason G; de Boer, Rob J

    2011-05-24

    One of the main questions in the field of imaging immune cell migration in living tissues is whether cells fulfill their functionality via random or nonrandom migration processes. For some applications, this issue has remained controversial even after publication of various imaging studies. A prime example is B-cell migration in germinal centers (GCs) where somatic hypermutation and clonal selection of B cells are thought to occur within morphologically distinct regions termed dark zone (DZ) and light zone (LZ). Here, we reanalyze a previously published dataset on GC B-cell migration, applying a sensitive analysis technique to detect directed migration and using a procedure to correct for a number of artifacts that frequently occur in time-lapse imaging experiments. Although B cells roughly perform a persistent random walk, we present evidence that they have a small preference (of on average about 0.2-0.3 μm min(-1)) to migrate from DZ to LZ, which is consistent with classical views of the GC reaction. This preference is most pronounced among a large subset of almost half of the B-cell population migrating along relatively straight tracks. Using a computational model to generate long-lasting B-cell tracks based on the experimental motility data (including the small directional preference), we predict a time course to travel from DZ to LZ of a few hours. This is consistent with experimental observations, and we show that at the observed cellular motility such a time course cannot be explained without the small preferential migration from DZ to LZ.

  20. Effects of valsartan on angiotensin II-induced migration of human coronary artery smooth muscle cells.

    Science.gov (United States)

    Kohno, M; Ohmori, K; Nozaki, S; Mizushige, K; Yasunari, K; Kano, H; Minami, M; Yoshikawa, J

    2000-11-01

    The migration as well as proliferation of coronary artery medial smooth muscle cells (SMC) into the intima is proposed to be an important process of intimal thickening in coronary atherosclerosis. In the current study, we examined the effects of the angiotensin type 1 receptor antagonist valsartan on angiotensin II (Ang II)-induced migration of cultured human coronary artery SMC using Boyden's chamber methods. Ang II significantly stimulated human coronary artery SMC migration in a concentration-dependent manner between 10(-6) and 10(-8) mol/l when cells of passage 4 to 6 were used. However, the migration response to Ang II was moderately decreased in cells of passage 10 to 12, and was markedly decreased in cells of passage 15 to 17, compared to that of passage 4 to 6. Ang II-induced migration was blocked by the Ang II type 1 (AT1) receptor antagonist valsartan in a concentration-dependent manner. By contrast, the Ang II type 2 (AT2) receptor antagonist PD 123319 did not affect Ang II-induced migration. Ang II modestly increased the cell number of human coronary artery SMC after a 24-h incubation. This increase in cell numbers was also clearly blocked by valsartan, but not by PD 123319. These results indicate that Ang II stimulates migration as well as proliferation via AT1 receptors in human coronary artery SMC when cells of passage 4 to 6 are used. Valsartan may prevent the progression of coronary atherosclerosis through an inhibition of Ang II-induced migration and proliferation in these cells, although in vivo evidence is lacking.

  1. Narrow-front loop migration in a population of the common cuckoo Cuculus canorus, as revealed by satellite telemetry

    NARCIS (Netherlands)

    Willemoes, Mikkel; Strandberg, Roine; Klaassen, Raymond H. G.; Tottrup, Anders P.; Vardanis, Yannis; Howey, Paul W.; Thorup, Kasper; Wikelski, Martin; Alerstam, Thomas

    2014-01-01

    Narrow migration corridors known in diurnal, social migrants such as raptors, storks and geese are thought to be caused by topographical leading line effects in combination with learning detailed routes across generations. Here, we document narrow-front migration in a nocturnal, solitary migrant,

  2. Doxycycline inhibits leukemic cell migration via inhibition of matrix metalloproteinases and phosphorylation of focal adhesion kinase.

    Science.gov (United States)

    Wang, Chunhuai; Xiang, Ru; Zhang, Xiangzhong; Chen, Yunxian

    2015-09-01

    Doxycycline, a tetracycline-based antibiotic, has been reported to attenuate melanoma cell migration through inhibiting the focal adhesion kinase (FAK) signaling pathway. However, it remains to be elucidated whether doxycycline exerts this effect on leukemia cell migration. The present study aimed to examine the role of doxycycline in leukemia cell migration. The invasion capacities of the human leukemia cell lines KG1a (acute myelogenous leukemia) and K562 (chronic myelogenous leukemia) were evaluated using Matrigel® matrix‑coated Transwell® chamber assays; leukemic cell lines treated with doxycycline (1 µg/ml) or anti‑β1‑integrin antibodies were added to the upper chamber, while untreated cells were included as controls. Reverse transcription quantitative polymerase chain reaction was performed in order to further understand the influence of doxycycline treatment on the expression of FAK and gelatinases in the KG1a and K562 leukemic cell lines. In addition, FAK protein expression and phosphorylation were determined using western blot analysis in order to investigate the mechanism by which doxycycline inhibited leukemic cell migration. The results revealed that doxycycline treatment significantly attenuated the migration of KG1a and K562 cells, which was demonstrated to be associated with inhibition of the expression and phosphorylation of FAK. In addition, doxycycline treatment inhibited matrix metalloproteinase (MMP)‑2 and MMP‑9 expression. Furthermore, incubation with blocking anti‑β1‑integrin antibodies had an analogous inhibitory effect on leukemic cell migration to that of doxycycline. In conclusion, the results of the present study suggested that doxycycline attenuated leukemic cell migration through inhibiting the FAK signaling pathway. Therefore, doxycycline may have potential for use as a novel strategy for the treatment of leukemia.

  3. Circadian Clock Genes Modulate Human Bone Marrow Mesenchymal Stem Cell Differentiation, Migration and Cell Cycle.

    Science.gov (United States)

    Boucher, Helene; Vanneaux, Valerie; Domet, Thomas; Parouchev, Alexandre; Larghero, Jerome

    2016-01-01

    Many of the components that regulate the circadian clock have been identified in organisms and humans. The influence of circadian rhythm (CR) on the regulation of stem cells biology began to be evaluated. However, little is known on the role of CR on human mesenchymal stem cell (hMSCs) properties. The objective of this study was to investigate the influence of CR on the differentiation capacities of bone marrow hMSCs, as well as the regulation of cell cycle and migration capabilities. To that, we used both a chemical approach with a GSK-3β specific inhibitor (2'E,3'Z-6-bromoindirubin-3'-oxime, BIO) and a knockdown of CLOCK and PER2, two of the main genes involved in CR regulation. In these experimental conditions, a dramatic inhibition of adipocyte differentiation was observed, while osteoblastic differentiation capacities were not modified. In addition, cell migration was decreased in PER2-/- cells. Lastly, downregulation of circadian clock genes induced a modification of the hMSCs cell cycle phase distribution, which was shown to be related to a change of the cyclin expression profile. Taken together, these data showed that CR plays a role in the regulation of hMSCs differentiation and division, and likely represent key factor in maintaining hMSCs properties.

  4. EphrinB3 restricts endogenous neural stem cell migration after traumatic brain injury.

    Science.gov (United States)

    Dixon, Kirsty J; Mier, Jose; Gajavelli, Shyam; Turbic, Alisa; Bullock, Ross; Turnley, Ann M; Liebl, Daniel J

    2016-11-01

    Traumatic brain injury (TBI) leads to a series of pathological events that can have profound influences on motor, sensory and cognitive functions. Conversely, TBI can also stimulate neural stem/progenitor cell proliferation leading to increased numbers of neuroblasts migrating outside their restrictive neurogenic zone to areas of damage in support of tissue integrity. Unfortunately, the factors that regulate migration are poorly understood. Here, we examine whether ephrinB3 functions to restrict neuroblasts from migrating outside the subventricular zone (SVZ) and rostral migratory stream (RMS). We have previously shown that ephrinB3 is expressed in tissues surrounding these regions, including the overlying corpus callosum (CC), and is reduced after controlled cortical impact (CCI) injury. Our current study takes advantage of ephrinB3 knockout mice to examine the influences of ephrinB3 on neuroblast migration into CC and cortex tissues after CCI injury. Both injury and/or ephrinB3 deficiency led to increased neuroblast numbers and enhanced migration outside the SVZ/RMS zones. Application of soluble ephrinB3-Fc molecules reduced neuroblast migration into the CC after injury and limited neuroblast chain migration in cultured SVZ explants. Our findings suggest that ephrinB3 expression in tissues surrounding neurogenic regions functions to restrict neuroblast migration outside the RMS by limiting chain migration.

  5. ATM regulation of IL-8 links oxidative stress to cancer cell migration and invasion.

    Science.gov (United States)

    Chen, Wei-Ta; Ebelt, Nancy D; Stracker, Travis H; Xhemalce, Blerta; Van Den Berg, Carla L; Miller, Kyle M

    2015-06-01

    Ataxia-telangiectasia mutated (ATM) protein kinase regulates the DNA damage response (DDR) and is associated with cancer suppression. Here we report a cancer-promoting role for ATM. ATM depletion in metastatic cancer cells reduced cell migration and invasion. Transcription analyses identified a gene network, including the chemokine IL-8, regulated by ATM. IL-8 expression required ATM and was regulated by oxidative stress. IL-8 was validated as an ATM target by its ability to rescue cell migration and invasion defects in ATM-depleted cells. Finally, ATM-depletion in human breast cancer cells reduced lung tumors in a mouse xenograft model and clinical data validated IL-8 in lung metastasis. These findings provide insights into how ATM activation by oxidative stress regulates IL-8 to sustain cell migration and invasion in cancer cells to promote metastatic potential. Thus, in addition to well-established roles in tumor suppression, these findings identify a role for ATM in tumor progression.

  6. Effects of N-acetylcysteine on matrix metalloproteinase-9 secretion and cell migration of human corneal epithelial cells

    OpenAIRE

    Ramaesh, T; Ramaesh, K; Riley, S C; West, J.D.; Dhillon, B

    2012-01-01

    Matrix metalloproteinase-9 (MMP-9) secreted by corneal epithelial cells has a role in the remodelling of extracellular matrix and migration of epithelial cells. Elevated levels of MMP-9 activity in the ocular surface may be involved in the pathogenesis of corneal diseases. N-acetylcysteine (NAC) has been used to treat corneal diseases, including recurrent epithelial erosions. In this study, its effects on the MMP-9 secretion and human corneal epithelial (HCE) cell migration were evaluated in ...

  7. Hyaluronan synthase 3 (HAS3) overexpression downregulates MV3 melanoma cell proliferation, migration and adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Takabe, Piia, E-mail: piia.takabe@uef.fi [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland); Bart, Geneviève [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland); Ropponen, Antti [University of Eastern Finland, Institute of Clinical Medicine, 70211 Kuopio (Finland); Rilla, Kirsi; Tammi, Markku; Tammi, Raija; Pasonen-Seppänen, Sanna [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland)

    2015-09-10

    Malignant skin melanoma is one of the most deadly human cancers. Extracellular matrix (ECM) influences the growth of malignant tumors by modulating tumor cells adhesion and migration. Hyaluronan is an essential component of the ECM, and its amount is altered in many tumors, suggesting an important role for hyaluronan in tumorigenesis. Nonetheless its role in melanomagenesis is not understood. In this study we produced a MV3 melanoma cell line with inducible expression of the hyaluronan synthase 3 (HAS3) and studied its effect on the behavior of the melanoma cells. HAS3 overexpression expanded the cell surface hyaluronan coat and decreased melanoma cell adhesion, migration and proliferation by cell cycle arrest at G1/G0. Melanoma cell migration was restored by removal of cell surface hyaluronan by Streptomyces hyaluronidase and by receptor blocking with hyaluronan oligosaccharides, while the effect on cell proliferation was receptor independent. Overexpression of HAS3 decreased ERK1/2 phosphorylation suggesting that inhibition of MAP-kinase signaling was responsible for these suppressive effects on the malignant phenotype of MV3 melanoma cells. - Highlights: • Inducible HAS3-MV3 melanoma cell line was generated using Lentiviral transduction. • HAS3 overexpression inhibits MV3 cell migration via hyaluronan–receptor interaction. • HAS3 overexpression decreases MV3 melanoma cell proliferation and adhesion. • ERK1/2 phosphorylation is downregulated by 50% in HAS3 overexpressing cells. • The results suggest that hyaluronan has anti-cancer like effects in melanoma.

  8. Differential satellite cell density of type I and II fibres with lifelong endurance running in old men

    DEFF Research Database (Denmark)

    Mackey, Abigail; Karlsen, A; Couppé, C

    2014-01-01

    between these variables were determined. RESULTS: In O-Un and O-Tr, type II fibres were smaller and contained fewer satellite cells than type I fibres. However, when expressed relative to fibre area, the difference in satellite cell content between fibre types was eliminated in O-Tr, but not O...... the satellite cell pool and (ii) is associated with a similar density of satellite cells in type I and II fibres despite a failure to preserve the equal fibre type distribution of satellite cells observed in young individuals. Taken together, these data reveal a differential regulation of satellite cell content...

  9. Tangential migration of glutamatergic neurons and cortical patterning during development: Lessons from Cajal-Retzius cells.

    Science.gov (United States)

    Barber, Melissa; Pierani, Alessandra

    2016-08-01

    Tangential migration is a mode of cell movement, which in the developing cerebral cortex, is defined by displacement parallel to the ventricular surface and orthogonal to the radial glial fibers. This mode of long-range migration is a strategy by which distinct neuronal classes generated from spatially and molecularly distinct origins can integrate to form appropriate neural circuits within the cortical plate. While it was previously believed that only GABAergic cortical interneurons migrate tangentially from their origins in the subpallial ganglionic eminences to integrate in the cortical plate, it is now known that transient populations of glutamatergic neurons also adopt this mode of migration. These include Cajal-Retzius cells (CRs), subplate neurons (SPs), and cortical plate transient neurons (CPTs), which have crucial roles in orchestrating the radial and tangential development of the embryonic cerebral cortex in a noncell-autonomous manner. While CRs have been extensively studied, it is only in the last decade that the molecular mechanisms governing their tangential migration have begun to be elucidated. To date, the mechanisms of SPs and CPTs tangential migration remain unknown. We therefore review the known signaling pathways, which regulate parameters of CRs migration including their motility, contact-redistribution and adhesion to the pial surface, and discuss this in the context of how CR migration may regulate their signaling activity in a spatial and temporal manner. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 847-881, 2016.

  10. The Caenorhabditis elegans Q neuroblasts : A powerful system to study cell migration at single-cell resolution in vivo

    NARCIS (Netherlands)

    Rella, Lorenzo; Fernandes Póvoa, Euclides E.; Korswagen, Hendrik C.

    2016-01-01

    During development, cell migration plays a central role in the formation of tissues and organs. Understanding the molecular mechanisms that drive and control these migrations is a key challenge in developmental biology that will provide important insights into disease processes, including cancer cel

  11. Convergent extension: using collective cell migration and cell intercalation to shape embryos.

    Science.gov (United States)

    Tada, Masazumi; Heisenberg, Carl-Philipp

    2012-11-01

    Body axis elongation represents a common and fundamental morphogenetic process in development. A key mechanism triggering body axis elongation without additional growth is convergent extension (CE), whereby a tissue undergoes simultaneous narrowing and extension. Both collective cell migration and cell intercalation are thought to drive CE and are used to different degrees in various species as they elongate their body axis. Here, we provide an overview of CE as a general strategy for body axis elongation and discuss conserved and divergent mechanisms underlying CE among different species.

  12. Migratory properties of cultured olfactory ensheathing cells by single-cell migration assay

    Institute of Scientific and Technical Information of China (English)

    Zhi-hui Huang; Ying Wang; Li Cao; Zhi-da Su; Yan-ling Zhu; Yi-zhang Chen; Xiao-bing Yuan; Cheng He

    2008-01-01

    Olfactory ensheathing cells (OECs) are a unique type of glial cells that have axonal growth-promoting properties. OEC transplantation has emerged as a promising experimental therapy of axonal injuries and demyelinating diseases. However, some fundamental cellular properties of OECs remain unclear. In this study, we found that the distinct OEC subpopulations exhibited different migratory properties based on time-lapse imaging of single isolated cells, possibly due to their different cytoskeletal organizations. Moreover, OEC subpopulations displayed different attractive migratory responses to a gradient of lysophosphatidic acid (LPA) in single-cell migration assays. Finally, we found that OEC subpopulations transformed into each other spontaneously. Together, these results demonstrate, for the first time to our knowledge, that distinct OEC subpopulations display different migratory properties in vitro and provide new evidence to support the notion of OECs as a single cell type with malleable functional phenotypes.

  13. Three-dimensional numerical model of cell morphology during migration in multi-signaling substrates.

    Directory of Open Access Journals (Sweden)

    Seyed Jamaleddin Mousavi

    Full Text Available Cell Migration associated with cell shape changes are of central importance in many biological processes ranging from morphogenesis to metastatic cancer cells. Cell movement is a result of cyclic changes of cell morphology due to effective forces on cell body, leading to periodic fluctuations of the cell length and cell membrane area. It is well-known that the cell can be guided by different effective stimuli such as mechanotaxis, thermotaxis, chemotaxis and/or electrotaxis. Regulation of intracellular mechanics and cell's physical interaction with its substrate rely on control of cell shape during cell migration. In this notion, it is essential to understand how each natural or external stimulus may affect the cell behavior. Therefore, a three-dimensional (3D computational model is here developed to analyze a free mode of cell shape changes during migration in a multi-signaling micro-environment. This model is based on previous models that are presented by the same authors to study cell migration with a constant spherical cell shape in a multi-signaling substrates and mechanotaxis effect on cell morphology. Using the finite element discrete methodology, the cell is represented by a group of finite elements. The cell motion is modeled by equilibrium of effective forces on cell body such as traction, protrusion, electrostatic and drag forces, where the cell traction force is a function of the cell internal deformations. To study cell behavior in the presence of different stimuli, the model has been employed in different numerical cases. Our findings, which are qualitatively consistent with well-known related experimental observations, indicate that adding a new stimulus to the cell substrate pushes the cell to migrate more directionally in more elongated form towards the more effective stimuli. For instance, the presence of thermotaxis, chemotaxis and electrotaxis can further move the cell centroid towards the corresponding stimulus, respectively

  14. Nuclear Membrane-Targeted Gold Nanoparticles Inhibit Cancer Cell Migration and Invasion.

    Science.gov (United States)

    Ali, Moustafa R K; Wu, Yue; Ghosh, Deepraj; Do, Brian H; Chen, Kuangcai; Dawson, Michelle R; Fang, Ning; Sulchek, Todd A; El-Sayed, Mostafa A

    2017-03-27

    Most cancer patients die from metastasis. Recent studies have shown that gold nanoparticles (AuNPs) can slow down the migration/invasion speed of cancer cells and suppress metastasis. Since nuclear stiffness of the cell largely decreases cell migration, our hypothesis is that targeting AuNPs to the cell nucleus region could enhance nuclear stiffness, and therefore inhibit cell migration and invasion. Our results showed that upon nuclear targeting of AuNPs, the ovarian cancer cell motilities decrease significantly, compared with nontargeted AuNPs. Furthermore, using atomic force microscopy, we observed an enhanced cell nuclear stiffness. In order to understand the mechanism of cancer cell migration/invasion inhibition, the exact locations of the targeted AuNPs were clearly imaged using a high-resolution three-dimensional imaging microscope, which showed that the AuNPs were trapped at the nuclear membrane. In addition, we observed a greatly increased expression level of lamin A/C protein, which is located in the inner nuclear membrane and functions as a structural component of the nuclear lamina to enhance nuclear stiffness. We propose that the AuNPs that are trapped at the nuclear membrane both (1) add to the mechanical stiffness of the nucleus and (2) stimulate the overexpression of lamin A/C located around the nuclear membrane, thus increasing nuclear stiffness and slowing cancer cell migration and invasion.

  15. Redundant control of migration and adhesion by ERM proteins in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Baeyens, Nicolas; Latrache, Iman; Yerna, Xavier [Laboratory of Cell Physiology, IoNS, Université Catholique de Louvain (Belgium); Noppe, Gauthier; Horman, Sandrine [Pôle de Recherche Cardiovasculaire, IREC, Université Catholique de Louvain (Belgium); Morel, Nicole, E-mail: nicole.morel@uclouvain.be [Laboratory of Cell Physiology, IoNS, Université Catholique de Louvain (Belgium)

    2013-11-22

    Highlights: •The three ERM proteins are expressed in vascular smooth muscle cell. •ERM depletion inhibited PDGF-evoked migration redundantly. •ERM depletion increased cell adhesion redundantly. •ERM depletion did not affect PDGF-evoked Ca signal, Rac1 activation, proliferation. •ERM proteins control PDGF-induced migration by regulating adhesion. -- Abstract: Ezrin, radixin, and moesin possess a very similar structure with a C-terminal actin-binding domain and a N-terminal FERM interacting domain. They are known to be involved in cytoskeleton organization in several cell types but their function in vascular smooth muscle cells (VSMC) is still unknown. The aim of this study was to investigate the role of ERM proteins in cell migration induced by PDGF, a growth factor involved in pathophysiological processes like angiogenesis or atherosclerosis. We used primary cultured VSMC obtained from rat aorta, which express the three ERM proteins. Simultaneous depletion of the three ERM proteins with specific siRNAs abolished the effects of PDGF on cell architecture and migration and markedly increased cell adhesion and focal adhesion size, while these parameters were only slightly affected by depletion of ezrin, radixin or moesin alone. Rac1 activation, cell proliferation, and Ca{sup 2+} signal in response to PDGF were unaffected by ERM depletion. These results indicate that ERM proteins exert a redundant control on PDGF-induced VSMC migration by regulating focal adhesion turn-over and cell adhesion to substrate.

  16. Angiogenin enhances cell migration by regulating stress fiber assembly and focal adhesion dynamics.

    Directory of Open Access Journals (Sweden)

    Saisai Wei

    Full Text Available Angiogenin (ANG acts on both vascular endothelial cells and cancer cells, but the underlying mechanism remains elusive. In this study, we carried out a co-immunoprecipitation assay in HeLa cells and identified 14 potential ANG-interacting proteins. Among these proteins, β-actin, α-actinin 4, and non-muscle myosin heavy chain 9 are stress fiber components and involved in cytoskeleton organization and movement, which prompted us to investigate the mechanism of action of ANG in cell migration. Upon confirmation of the interactions between ANG and the three proteins, further studies revealed that ANG co-localized with β-actin and α-actinin 4 at the leading edge of migrating cells. Down-regulation of ANG resulted in fewer but thicker stress fibers with less dynamics, which was associated with the enlargements of focal adhesions. The focal adhesion kinase activity and cell migration capacity were significantly decreased in ANG-deficient cells. Taken together, our data demonstrated that the existence of ANG in the cytoplasm optimizes stress fiber assembly and focal adhesion formation to accommodate cell migration. The finding that ANG promoted cancer cell migration might provide new clues for tumor metastasis research.

  17. Directed migration of human bone marrow mesenchymal stem cells in a physiological direct current electric field

    Directory of Open Access Journals (Sweden)

    Z Zhao

    2011-11-01

    Full Text Available At sites of bone fracture, naturally-occurring electric fields (EFs exist during healing and may guide cell migration. In this study, we investigated whether EFs could direct the migration of bone marrow mesenchymal stem cells (BM-MSCs, which are known to be key players in bone formation. Human BM-MSCs were cultured in direct current EFs of 10 to 600 mV/mm. Using time-lapse microscopy, we demonstrated that an EF directed migration of BM-MSCs mainly to the anode. Directional migration occurred at a low threshold and with a physiological EF of ~25 mV/mm. Increasing the EF enhanced the MSC migratory response. The migration speed peaked at 300 mV/mm, at a rate of 42 ±1 µm/h, around double the control (no EF migration rate. MSCs showed sustained response to prolonged EF application in vitro up to at least 8 h. The electrotaxis of MSCs with either early (P3-P5 or late (P7-P10 passage was also investigated. Migration was passage-dependent with higher passage number showing reduced directed migration, within the range of passages examined. An EF of 200 mV/mm for 2 h did not affect cell senescence, phenotype, or osteogenic potential of MSCs, regardless of passage number within the range tested (P3-P10. Our findings indicate that EFs are a powerful cue in directing migration of human MSCs in vitro. An applied EF may be useful to control or enhance migration of MSCs during bone healing.

  18. Effects of SOX2 on Proliferation, Migration and Adhesion of Human Dental Pulp Stem Cells.

    Science.gov (United States)

    Liu, Pengfei; Cai, Jinglei; Dong, Delu; Chen, Yaoyu; Liu, Xiaobo; Wang, Yi; Zhou, Yulai

    2015-01-01

    As a key factor for cell pluripotent and self-renewing phenotypes, SOX2 has attracted scientists' attention gradually in recent years. However, its exact effects in dental pulp stem cells (DPSCs) are still unclear. In this study, we mainly investigated whether SOX2 could affect some biological functions of DPSCs. DPSCs were isolated from the dental pulp of human impacted third molar. SOX2 overexpressing DPSCs (DPSCs-SOX2) were established through retroviral infection. The effect of SOX2 on cell proliferation, migration and adhesion ability was evaluated with CCK-8, trans-well system and fibronectin-induced cell attachment experiment respectively. Whole genome expression of DPSCs-SOX2 was analyzed with RNA microarray. Furthermore, a rescue experiment was performed with SOX2-siRNA in DPSC-SOX2 to confirm the effect of SOX2 overexpression in DPSCs. We found that SOX2 overexpression could result in the enhancement of cell proliferation, migration, and adhesion in DPSCs obviously. RNA microarray analysis indicated that some key genes in the signal pathways associated with cell cycle, migration and adhesion were upregulated in different degree, and the results were further confirmed with qPCR and western-blot. Finally, DPSC-SOX2 transfected with SOX2-siRNA showed a decrease of cell proliferation, migration and adhesion ability, which further confirmed the biological effect of SOX2 in human DPSCs. This study indicated that SOX2 could improve the cell proliferation, migration and adhesion ability of DPSCs through regulating gene expression about cell cycle, migration and adhesion, and provided a novel strategy to develop seed cells with strong proliferation, migration and adhesion ability for tissue engineering.

  19. Effects of SOX2 on Proliferation, Migration and Adhesion of Human Dental Pulp Stem Cells.

    Directory of Open Access Journals (Sweden)

    Pengfei Liu

    Full Text Available As a key factor for cell pluripotent and self-renewing phenotypes, SOX2 has attracted scientists' attention gradually in recent years. However, its exact effects in dental pulp stem cells (DPSCs are still unclear. In this study, we mainly investigated whether SOX2 could affect some biological functions of DPSCs. DPSCs were isolated from the dental pulp of human impacted third molar. SOX2 overexpressing DPSCs (DPSCs-SOX2 were established through retroviral infection. The effect of SOX2 on cell proliferation, migration and adhesion ability was evaluated with CCK-8, trans-well system and fibronectin-induced cell attachment experiment respectively. Whole genome expression of DPSCs-SOX2 was analyzed with RNA microarray. Furthermore, a rescue experiment was performed with SOX2-siRNA in DPSC-SOX2 to confirm the effect of SOX2 overexpression in DPSCs. We found that SOX2 overexpression could result in the enhancement of cell proliferation, migration, and adhesion in DPSCs obviously. RNA microarray analysis indicated that some key genes in the signal pathways associated with cell cycle, migration and adhesion were upregulated in different degree, and the results were further confirmed with qPCR and western-blot. Finally, DPSC-SOX2 transfected with SOX2-siRNA showed a decrease of cell proliferation, migration and adhesion ability, which further confirmed the biological effect of SOX2 in human DPSCs. This study indicated that SOX2 could improve the cell proliferation, migration and adhesion ability of DPSCs through regulating gene expression about cell cycle, migration and adhesion, and provided a novel strategy to develop seed cells with strong proliferation, migration and adhesion ability for tissue engineering.

  20. Extracellular vesicles from malignant effusions induce tumor cell migration: inhibitory effect of LMWH tinzaparin.

    Science.gov (United States)

    Gamperl, Hans; Plattfaut, Corinna; Freund, Annika; Quecke, Tabea; Theophil, Friederike; Gieseler, Frank

    2016-10-01

    Elevated levels of extracellular vesicles (EVs) have been correlated with inflammatory diseases as well as progressive and metastatic cancer. By presenting tissue factor (TF) on their membrane surface, cellular microparticles (MPs) activate both the coagulation system and cell-signaling pathways such as the PAR/ERK pathway. We have shown before that malignant effusions are a rich source of tumor cell-derived EVs. Here, we used EVs from malignant effusions from three different patients after serial low-speed centrifugation steps as recommended by the ISTH (lsEV). Significant migration of human pancreatic carcinoma cells could be induced by lsEVs and was effectively inhibited by pre-incubation with tinzaparin, a low-molecular-weight heparin. Tinzaparin induced tissue factor pathway inhibitor (TFPI) release from tumor cells, and recombinant TFPI inhibited EV-induced tumor cell migration. EVs also induced ERK phosphorylation, whereas inhibitors of PAR2 and ERK suppressed EV-induced tumor cell migration. LsEVs have been characterized by high-resolution flow cytometry and, after elimination of smaller vesicles including exosomes, by further high-speed centrifugation (hsEV). The remaining population consisting primarily of MPs is indeed the main migration-inducing population with tenase activity. Compared to other LMWHs, tinzaparin is suggested to have high potency to induce TFPI release from epithelial cells. The migration-inhibitory effect of TFPI and the interruption of tumor cell migration by inhibitors of PAR2 and ERK suggest that lsEVs induce tumor cell migration by activating the PAR2 signaling pathway. Tinzaparin might inhibit this process at least partly by inducing the release of TFPI from tumor cells, which blocks PAR-activating TF complexes. The clinical relevance of the results is discussed.

  1. R-Ras regulates migration through an interaction with filamin A in melanoma cells.

    Directory of Open Access Journals (Sweden)

    Joanna E Gawecka

    Full Text Available BACKGROUND: Changes in cell adhesion and migration in the tumor microenvironment are key in the initiation and progression of metastasis. R-Ras is one of several small GTPases that regulate cell adhesion and migration on the extracellular matrix, however the mechanism has not been completely elucidated. Using a yeast two-hybrid approach we sought to identify novel R-Ras binding proteins that might mediate its effects on integrins. METHODS AND FINDINGS: We identified Filamin A (FLNa as a candidate interacting protein. FLNa is an actin-binding scaffold protein that also binds to integrin beta1, beta2 and beta7 tails and is associated with diverse cell processes including cell migration. Indeed, M2 melanoma cells require FLNa for motility. We further show that R-Ras and FLNa interact in co-immunoprecipitations and pull-down assays. Deletion of FLNa repeat 3 (FLNaDelta3 abrogated this interaction. In M2 melanoma cells active R-Ras co-localized with FLNa but did not co-localize with FLNa lacking repeat 3. Thus, activated R-Ras binds repeat 3 of FLNa. The functional consequence of this interaction was that active R-Ras and FLNa coordinately increased cell migration. In contrast, co-expression of R-Ras and FLNaDelta3 had a significantly reduced effect on migration. While there was enhancement of integrin activation and fibronectin matrix assembly, cell adhesion was not altered. Finally, siRNA knockdown of endogenous R-Ras impaired FLNa-dependent fibronectin matrix assembly. CONCLUSIONS: These data support a model in which R-Ras functionally associates with FLNa and thereby regulates integrin-dependent migration. Thus in melanoma cells R-Ras and FLNa may cooperatively promote metastasis by enhancing cell migration.

  2. SLUG promotes prostate cancer cell migration and invasion via CXCR4/CXCL12 axis

    Directory of Open Access Journals (Sweden)

    Uygur Berna

    2011-11-01

    Full Text Available Abstract Background SLUG is a zinc-finger transcription factor of the Snail/Slug zinc-finger family that plays a role in migration and invasion of tumor cells. Mechanisms by which SLUG promotes migration and invasion in prostate cancers remain elusive. Methods Expression level of CXCR4 and CXCL12 was examined by Western blot, RT-PCR, and qPCR analyses. Forced expression of SLUG was mediated by retroviruses, and SLUG and CXCL12 was downregulated by shRNAs-expressing lentiviruses. Migration and invasion of prostate cancer were measured by scratch-wound assay and invasion assay, respectively. Research We demonstrated that forced expression of SLUG elevated CXCR4 and CXCL12 expression in human prostate cancer cell lines PC3, DU145, 22RV1, and LNCaP; conversely, reduced expression of SLUG by shRNA downregulated CXCR4 and CXCL12 expression at RNA and protein levels in prostate cancer cells. Furthermore, ectopic expression of SLUG increased MMP9 expression and activity in PC3, 22RV1, and DU-145 cells, and SLUG knockdown by shRNA downregulated MMP9 expression. We showed that CXCL12 is required for SLUG-mediated MMP9 expression in prostate cancer cells. Moreover, we found that migration and invasion of prostate cancer cells was increased by ectopic expression of SLUG and decreased by SLUG knockdown. Notably, knockdown of CXCL12 by shRNA impaired SLUG-mediated migration and invasion in prostate cancer cells. Lastly, our data suggest that CXCL12 and SLUG regulate migration and invasion of prostate cancer cells independent of cell growth. Conclusion We provide the first compelling evidence that upregulation of autocrine CXCL12 is a major mechanism underlying SLUG-mediated migration and invasion of prostate cancer cells. Our findings suggest that CXCL12 is a therapeutic target for prostate cancer metastasis.

  3. Polymorphonuclear cells stimulate the migration and metastatic potential of rat sarcoma cells.

    Science.gov (United States)

    Remedi, María Mónica; Donadio, Ana Carolina; Chiabrando, Gustavo Alberto

    2009-02-01

    The tumour microenvironment, which is largely composed of inflammatory cells, is a crucial participant in the neoplastic process through the promotion of cell proliferation, survival and migration. Neutrophil polymorphonuclear cells (PMNs) induce inflammatory reactions that can be either cytotoxic for tumour cells or can promote tumour growth and metastasis. Previously, we have reported a spontaneous metastasis tumour model that has tumour PMNs infiltration, and metastasis, to liver and spleen. The aim of this study was to evaluate the PMNs influences on the tumour cell invasion and metastatic properties. We analysed intercellular adhesion molecule-1 (ICAM-1), urokinase-type plasminogen activator receptor (uPAR), MT1-MMP (membrane type 1-matrix metalloproteinase) and MMP2 protein expression in TuE-t cells cultured with PMNs or PMNs-conditioned medium isolated from tumour bearing and normal rats. The interaction between tumour cells and PMNs induced a decrease in ICAM-1 expression in tumour cells as well as an increase in MMP2 and tumour cell motility. Besides, conserved expression of uPAR and MT1-MMP in tumour cells was also demonstrated. The up-regulation in MMP2 associated with uPAR and MT1-MMP conserved expression may be related to an increased extracellular matrix proteolysis. These results showed that the interaction of tumour cells with PMNs could favour tumour cell spreading through the promotion of a tumour invasive phenotype.

  4. On the role of PDZ domain-encoding genes in Drosophila border cell migration.

    Science.gov (United States)

    Aranjuez, George; Kudlaty, Elizabeth; Longworth, Michelle S; McDonald, Jocelyn A

    2012-11-01

    Cells often move as collective groups during normal embryonic development and wound healing, although the mechanisms governing this type of migration are poorly understood. The Drosophila melanogaster border cells migrate as a cluster during late oogenesis and serve as a powerful in vivo genetic model for collective cell migration. To discover new genes that participate in border cell migration, 64 out of 66 genes that encode PDZ domain-containing proteins were systematically targeted by in vivo RNAi knockdown. The PDZ domain is one of the largest families of protein-protein interaction domains found in eukaryotes. Proteins that contain PDZ domains participate in a variety of biological processes, including signal transduction and establishment of epithelial apical-basal polarity. Targeting PDZ proteins effectively assesses a larger number of genes via the protein complexes and pathways through which these proteins function. par-6, a known regulator of border cell migration, was a positive hit and thus validated the approach. Knockdown of 14 PDZ domain genes disrupted migration with multiple RNAi lines. The candidate genes have diverse predicted cellular functions and are anticipated to provide new insights into the mechanisms that control border cell movement. As a test of this concept, two genes that disrupted migration were characterized in more detail: big bang and the Dlg5 homolog CG6509. We present evidence that Big bang regulates JAK/STAT signaling, whereas Dlg5/CG6509 maintains cluster cohesion. Moreover, these results demonstrate that targeting a selected class of genes by RNAi can uncover novel regulators of collective cell migration.

  5. Sox2 promotes survival of satellite glial cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-08-14

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

  6. The candidate tumor suppressor gene ECRG4 inhibits cancer cells migration and invasion in esophageal carcinoma

    Directory of Open Access Journals (Sweden)

    Lu ShihHsin

    2010-10-01

    Full Text Available Abstract Background The esophageal cancer related gene 4 (ECRG4 was initially identified and cloned in our laboratory from human normal esophageal epithelium (GenBank accession no.AF325503. ECRG4 was a new tumor suppressor gene in esophageal squamous cell carcinoma (ESCC associated with prognosis. In this study, we investigated the novel tumor-suppressing function of ECRG4 in cancer cell migration, invasion, adhesion and cell cycle regulation in ESCC. Methods Transwell and Boyden chamber experiments were utilized to examined the effects of ECRG4 expression on ESCC cells migration, invasion and adhesion. And flow cytometric analysis was used to observe the impact of ECRG4 expression on cell cycle regulation. Finally, the expression levels of cell cycle regulating proteins p53 and p21 in human ESCC cells transfected with ECRG4 gene were evaluated by Western blotting. Results The restoration of ECRG4 expression in ESCC cells inhibited cancer cells migration and invasion (P P > 0.05. Furthermore, ECRG4 could cause cell cycle G1 phase arrest in ESCC (P Conclusion ECRG4 is a candidate tumor suppressor gene which suppressed tumor cells migration and invasion without affecting cell adhesion ability in ESCC. Furthermore, ECRG4 might cause cell cycle G1 phase block possibly through inducing the increased expression of p53 and p21 proteins in ESCC.

  7. A mathematical model coupling polarity signaling to cell adhesion explains diverse cell migration patterns.

    Directory of Open Access Journals (Sweden)

    William R Holmes

    2017-05-01

    Full Text Available Protrusion and retraction of lamellipodia are common features of eukaryotic cell motility. As a cell migrates through its extracellular matrix (ECM, lamellipod growth increases cell-ECM contact area and enhances engagement of integrin receptors, locally amplifying ECM input to internal signaling cascades. In contrast, contraction of lamellipodia results in reduced integrin engagement that dampens the level of ECM-induced signaling. These changes in cell shape are both influenced by, and feed back onto ECM signaling. Motivated by experimental observations on melanoma cells lines (1205Lu and SBcl2 migrating on fibronectin (FN coated topographic substrates (anisotropic post-density arrays, we probe this interplay between intracellular and ECM signaling. Experimentally, cells exhibited one of three lamellipodial dynamics: persistently polarized, random, or oscillatory, with competing lamellipodia o