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Sample records for cells targeted calcium-mediated

  1. Growth control in colon epithelial cells: gadolinium enhances calcium-mediated growth regulation.

    Science.gov (United States)

    Attili, Durga; Jenkins, Brian; Aslam, Muhammad Nadeem; Dame, Michael K; Varani, James

    2012-12-01

    Gadolinium, a member of the lanthanoid family of transition metals, interacts with calcium-binding sites on proteins and other biological molecules. The overall goal of the present investigation was to determine if gadolinium could enhance calcium-induced epithelial cell growth inhibition in the colon. Gadolinium at concentrations as low as 1-5 μM combined with calcium inhibits proliferation of human colonic epithelial cells more effectively than calcium alone. Gadolinium had no detectable effect on calcium-induced differentiation in the same cells based on change in cell morphology, induction of E-cadherin synthesis, and translocation of E-cadherin from the cytosol to the cell surface. When the colon epithelial cells were treated with gadolinium and then exposed to increased calcium concentrations, movement of extracellular calcium into the cell was suppressed. In contrast, gadolinium treatment had no effect on ionomycin-induced release of stored intracellular calcium into the cytoplasm. Whether these in vitro observations can be translated into an approach for reducing abnormal proliferation in the colonic mucosa (including polyp formation) is not known. These results do, however, provide an explanation for our recent findings that a multi-mineral supplement containing all of the naturally occurring lanthanoid metals including gadolinium are more effective than calcium alone in preventing colon polyp formation in mice on a high-fat diet.

  2. Upregulation and activation of caspase-3 or caspase-8 and elevation of intracellular free calcium mediated apoptosis of indomethacin-induced K562 cells

    Institute of Scientific and Technical Information of China (English)

    张广森; 周光飚; 戴崇文

    2004-01-01

    Background A nonsteroidal anti-inflammatory drug, indomethacin, has been shown to have anti-leukemic activity and induce leukemic cell opoptosis. This study was to elucidate the mechanism of indomethacin-induced K562 cell apoptosis.Methods K562 cells were grown in RPMI 1640 medium and treated with different doses of indomethacin (0 μmol/L, 100 μmol/L, 200 μmol/L, 400 μmol/L, 800 μmol/L) for 72 hours. The cells were harvested, and cell viability or apoptosis was analyzed using MTT assay and AO/EB stain, combining laser scanning confocal microscopy (LSCM) technique separately. For the localization and distribution of intracellular caspase-3 or caspase-8 protein, immunofluorescence assay was carried out. To reveal the activation of caspase-3 or caspase-8 in indomethacin-treated cells, Western blot detection was used. The change in intracellular free calcium was determined by Fluo-3/ Am probe labeling combined with LSCM. Results Indomethacin could lead to K562 cell apoptosis and inhibit cell viability in a concentration-dependent manner. An increased expression of intracellular caspase-3 or caspase-8 was observed at higher doses of indomethacin (400-800 μmol/L). Western blot results showed upregrulation and activation in both caspase-3 and caspase-8 protein. Under indomethacin intervention, the levels of intracellular free calcium showed a significant increase. Blocking the activity of cyclooxygenase did not abolish the effects of indomethacin on K562 cell apoptosis.Conclusions Activation and upregulation of caspase-3 or caspase-8 protein were responsible for Indomethacin-induced K562 cell apoptosis. Variation of intracellular free calcium might switch on the apoptotic pathway and the proapoptotic effect of indomethacin might be cyclooxygenase-independent.

  3. Negundoside, an irridiod glycoside from leaves of Vitex negundo, protects human liver cells against calcium-mediated toxicity induced by carbon tetrachloride

    Institute of Scientific and Technical Information of China (English)

    Sheikh A Tasduq; Peerzada J Kaiser; Bishan D Gupta; Vijay K Gupta; Rakesh K Johri

    2008-01-01

    AIM: To evaluate the protective effect of 2'-p-hydroxy benzoylmussaenosidic acid [negundoside (NG), against carbon tetrachloride (CCl4)-induced toxicity in HUH-7 cells.METHODS: CCl4 is a well characterized hepatotoxin, and inducer of cytochrome P4502E1 (CYP2E1)-mediated oxidative stress. In addition, lipid peroxidation and accumulation of intracellular calcium are important steps in the pathway involved in CCl4 toxicity. Liver cells (HUH-7) were treated with CCl4, and the mechanism of the cytoprotective effect of NG was assessed. Silymarin, a known hepatoprotective drug, was used as control.RESULTS: NG protected HUH-7 cells against CCl4 toxicity and loss of viability without modulating CYP2E1 activity. Prevention of CCl4, toxicity was associated with a reduction in oxidative damage as reflected by decreased generation of reactive oxygen species (ROS), a decrease in lipid peroxidation and accumulation of intracellular Ca2+ levels and maintenance of intracellular glutathione homeostasis. Decreased mitochondrial membrane potential (MMP), induction of caspases mediated DNA fragmentation and cell cycle arrest, as a result of CCl4 treatment, were also blocked by NG. The protection afforded by NG seemed to be mediated by activation of cyclic adenosine monophosphate (cAMP) synthesis and inhibition of phospholipases (cPLA2).CONCLUSION: NG exerts a protective effect on CYP2El-dependent CCl4 toxicity via inhibition of lipid peroxidation, followed by an improved intracellular calcium homeostasis and inhibition of Ca2+-dependent proteases.

  4. Cellular Mechanisms of Calcium-Mediated Triggered Activity

    Science.gov (United States)

    Song, Zhen

    Life-threatening cardiac arrhythmias continue to pose a major health problem. Ventricular fibrillation, which is a complex form of electrical wave turbulence in the lower chambers of the heart, stops the heart from pumping and is the largest cause of natural death in the United States. Atrial fibrillation, a related form of wave turbulence in the upper heart chambers, is in turn the most common arrhythmia diagnosed in clinical practice. Despite extensive research to date, mechanisms of cardiac arrhythmias remain poorly understood. It is well established that both spatial disorder of the refractory period of heart cells and triggered activity (TA) jointly contribute to the initiation and maintenance of arrhythmias. TA broadly refers to the abnormal generation of a single or a sequence of abnormal excitation waves from a small submillimeter region of the heart in the interval of time between two normal waves generated by the heart's natural pacemaker (the sinoatrial node). TA has been widely investigated experimentally and occurs in several pathological conditions where the intracellular concentration of free Ca2+ ions in heart cells becomes elevated. Under such conditions, Ca2+ can be spontaneously released from intracellular stores, thereby driving an electrogenic current that exchanges 3Na+ ions for one Ca2+ ion across the cell membrane. This current in turn depolarizes the membrane of heart cells after a normal excitation. If this calcium-mediated "delayed after depolarization'' (DAD) is sufficiently large, it can generate an action potential. While the arrhythmogenic importance of spontaneous Ca2+ release and DADs is well appreciated, the conditions under which they occur in heart pathologies remain poorly understood. Calcium overload is only one factor among several other factors that can promote DADs, including sympathetic nerve stimulation, different expression levels of membrane ion channels and calcium handling proteins, and different mutations of those

  5. In vivo immunotoxicity of perfluorooctane sulfonate in BALB/c mice: Identification of T-cell receptor and calcium-mediated signaling pathway disruption through gene expression profiling of the spleen.

    Science.gov (United States)

    Lv, Qi-Yan; Wan, Bin; Guo, Liang-Hong; Yang, Yu; Ren, Xiao-Min; Zhang, Hui

    2015-10-05

    Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant that is used worldwide and is continuously being detected in biota and the environment, thus presenting potential threats to the ecosystem and human health. Although PFOS is highly immunotoxic, its underlying molecular mechanisms remain largely unknown. The present study examined PFOS-induced immunotoxicity in the mouse spleen and explored its underlying mechanisms by gene expression profiling. Oral exposure of male BALB/c mice for three weeks followed by one-week recovery showed that a 10 mg/kg/day PFOS exposure damaged the splenic architecture, inhibited T-cell proliferation in response to mitogen, and increased the percentages of T helper (CD3(+)CD4(+)) and cytotoxic T (CD3(+)CD8(+)) cells, despite the decrease in the absolute number of these cells. A delayed type of PFOS immunotoxicity was observed, which mainly occurred during the recovery period. Global gene expression profiling of mouse spleens and QRT-PCR analyses suggest that PFOS inhibited the expression of genes involved in cell cycle regulation and NRF2-mediated oxidative stress response, and upregulated those in TCR signaling, calcium signaling, and p38/MAPK signaling pathways. Western blot analysis confirmed that the expressions of CAMK4, THEMIS, and CD3G, which were involved in the upregulated pathways, were induced upon PFOS exposure. Acute PFOS exposure modulated calcium homoeostasis in splenocytes. These results indicate that PFOS exposure can activate TCR signaling and calcium ion influx, which provides a clue for the potential mechanism of PFOS immunotoxicity. The altered signaling pathways by PFOS treatment as revealed in the present study might facilitate in better understanding PFOS immunotoxicity and explain the association between immune disease and PFOS exposure.

  6. Targeting Notch to target cancer stem cells.

    Science.gov (United States)

    Pannuti, Antonio; Foreman, Kimberly; Rizzo, Paola; Osipo, Clodia; Golde, Todd; Osborne, Barbara; Miele, Lucio

    2010-06-15

    The cellular heterogeneity of neoplasms has been at the center of considerable interest since the "cancer stem cell hypothesis", originally formulated for hematologic malignancies, was extended to solid tumors. The origins of cancer "stem" cells (CSC) or tumor-initiating cells (TIC; henceforth referred to as CSCs) and the methods to identify them are hotly debated topics. Nevertheless, the existence of subpopulations of tumor cells with stem-like characteristics has significant therapeutic implications. The stem-like phenotype includes indefinite self-replication, pluripotency, and, importantly, resistance to chemotherapeutics. Thus, it is plausible that CSCs, regardless of their origin, may escape standard therapies and cause disease recurrences and/or metastasis after apparently complete remissions. Consequently, the idea of selectively targeting CSCs with novel therapeutics is gaining considerable interest. The Notch pathway is one of the most intensively studied putative therapeutic targets in CSC, and several investigational Notch inhibitors are being developed. However, successful targeting of Notch signaling in CSC will require a thorough understanding of Notch regulation and the context-dependent interactions between Notch and other therapeutically relevant pathways. Understanding these interactions will increase our ability to design rational combination regimens that are more likely to prove safe and effective. Additionally, to determine which patients are most likely to benefit from treatment with Notch-targeting therapeutics, reliable biomarkers to measure pathway activity in CSC from specific tumors will have to be identified and validated. This article summarizes the most recent developments in the field of Notch-targeted cancer therapeutics, with emphasis on CSC.

  7. Killing cells by targeting mitosis.

    Science.gov (United States)

    Manchado, E; Guillamot, M; Malumbres, M

    2012-03-01

    Cell cycle deregulation is a common feature of human cancer. Tumor cells accumulate mutations that result in unscheduled proliferation, genomic instability and chromosomal instability. Several therapeutic strategies have been proposed for targeting the cell division cycle in cancer. Whereas inhibiting the initial phases of the cell cycle is likely to generate viable quiescent cells, targeting mitosis offers several possibilities for killing cancer cells. Microtubule poisons have proved efficacy in the clinic against a broad range of malignancies, and novel targeted strategies are now evaluating the inhibition of critical activities, such as cyclin-dependent kinase 1, Aurora or Polo kinases or spindle kinesins. Abrogation of the mitotic checkpoint or targeting the energetic or proteotoxic stress of aneuploid or chromosomally instable cells may also provide further benefits by inducing lethal levels of instability. Although cancer cells may display different responses to these treatments, recent data suggest that targeting mitotic exit by inhibiting the anaphase-promoting complex generates metaphase cells that invariably die in mitosis. As the efficacy of cell-cycle targeting approaches has been limited so far, further understanding of the molecular pathways modulating mitotic cell death will be required to move forward these new proposals to the clinic.

  8. Targeting tumour Cell Plasticity

    Institute of Scientific and Technical Information of China (English)

    Elizabeth D. WILLIAMS

    2009-01-01

    @@ Her research is focused on understanding the mechanisms of tumour progression and metastasis, particularly in uro-logical carcinomas (bladder and prostate). Tumour cell plasticity, including epithelial-mesenchymal transition, is a cen-tral theme in Dr Williams' work.

  9. Novel vistas of calcium-mediated signalling in the thalamus.

    Science.gov (United States)

    Pape, Hans-Christian; Munsch, Thomas; Budde, Thomas

    2004-05-01

    Traditionally, the role of calcium ions (Ca(2+)) in thalamic neurons has been viewed as that of electrical charge carriers. Recent experimental findings in thalamic cells have only begun to unravel a highly complex Ca(2+) signalling network that exploits extra- and intracellular Ca(2+) sources. In thalamocortical relay neurons, interactions between T-type Ca(2+) channel activation, Ca(2+)-dependent regulation of adenylyl cyclase activity and the hyperpolarization-activated cation current ( I(h)) regulate oscillatory burst firing during periods of sleep and generalized epilepsy, while a functional triad between Ca(2+) influx through high-voltage-activated (most likely L-type) Ca(2+) channels, Ca(2+)-induced Ca(2+) release via ryanodine receptors (RyRs) and a repolarizing mechanism (possibly via K(+) channels of the BK(Ca) type) supports tonic spike firing as required during wakefulness. The mechanisms seem to be located mostly at dendritic and somatic sites, respectively. One functional compartment involving local GABAergic interneurons in certain thalamic relay nuclei is the glomerulus, in which the dendritic release of GABA is regulated by Ca(2+) influx via canonical transient receptor potential channels (TRPC), thereby presumably enabling transmitters of extrathalamic input systems that are coupled to phospholipase C (PLC)-activating receptors to control feed-forward inhibition in the thalamus. Functional interplay between T-type Ca(2+) channels in dendrites and the A-type K(+) current controls burst firing, contributing to the range of oscillatory activity observed in these interneurons. GABAergic neurons in the reticular thalamic (RT) nucleus recruit a specific set of Ca(2+)-dependent mechanisms for the generation of rhythmic burst firing, of which a particular T-type Ca(2+) channel in the dendritic membrane, the Ca(2+)-dependent activation of non-specific cation channels ( I(CAN)) and of K(+) channels (SK(Ca) type) are key players. Glial Ca(2+) signalling in

  10. Targeting vaccines to dendritic cells.

    Science.gov (United States)

    Foged, Camilla; Sundblad, Anne; Hovgaard, Lars

    2002-03-01

    Dendritic cells (DC) are specialized antigen presenting cells (APC) with a remarkable ability to take up antigens and stimulate major histocompatibility complex (MHC)-restricted specific immune responses. Recent discoveries have shown that their role in initiating primary immune responses seems to be far superior to that of B-cells and macrophages. DC are localized at strategic places in the body at sites used by pathogens to enter the organism, and are thereby in an optimal position to capture antigens. In general, vaccination strategies try to mimic the invasiveness of the pathogens. DC are considered to play a central role for the provocation of primary immune responses by vaccination. A rational way of improving the potency and safety of new and already existing vaccines could therefore be to direct vaccines specifically to DC. There is a need for developing multifunctional vaccine drug delivery systems (DDS) with adjuvant effect that target DC directly and induce optimal immune responses. This paper will review the current knowledge of DC physiology as well as the progress in the field of novel vaccination strategies that directly or indirectly aim at targeting DC.

  11. Potential targets for lung squamous cell carcinoma

    Science.gov (United States)

    Researchers have identified potential therapeutic targets in lung squamous cell carcinoma, the second most common form of lung cancer. The Cancer Genome Atlas (TCGA) Research Network study comprehensively characterized the lung squamous cell carcinoma gen

  12. Targeting vaccines to dendritic cells

    DEFF Research Database (Denmark)

    Foged, Camilla; Sundblad, Anne; Hovgaard, Lars

    2002-01-01

    delivery systems (DDS) with adjuvant effect that target DC directly and induce optimal immune responses. This paper will review the current knowledge of DC physiology as well as the progress in the field of novel vaccination strategies that directly or indirectly aim at targeting DC....

  13. Targeting influenza virosomes to ovarian carcinoma cells

    NARCIS (Netherlands)

    Mastrobattista, E; Schoen, P; Wilschut, J; Crommelin, DJA; Storm, G

    2001-01-01

    Reconstituted influenza virus envelopes (virosomes) containing the viral hemagglutinin (HA) have attracted attention as delivery vesicles for cytosolic drug delivery as they possess membrane fusion activity. Here, we show that influenza virosomes can be targeted towards ovarian carcinoma cells (OVCA

  14. HIV-1 target cells in the CNS

    OpenAIRE

    Joseph, Sarah B.; Arrildt, Kathryn T.; Sturdevant, Christa B.; Swanstrom, Ronald

    2014-01-01

    HIV-1 replication in the central nervous system (CNS) is typically limited by the availability of target cells. HIV-1 variants that are transmitted and dominate the early stages of infection almost exclusively use the CCR5 coreceptor and are well adapted to entering, and thus infecting, cells expressing high CD4 densities similar to those found on CD4+ T cells. While the “immune privileged” CNS is largely devoid of CD4+ T cells, macrophage and microglia are abundant throughout ...

  15. Targeted destruction of HIV-positive cells

    Directory of Open Access Journals (Sweden)

    Jyoti R Sharma

    2014-11-01

    Full Text Available Introduction: HIV/AIDS is now a global epidemic that has become the leading infectious killer of adults worldwide. Although antiretroviral (ARV therapy has dramatically improved the quality of life and increased the life expectancy of those infected with HIV but frequency of dosing and drug toxicity as well as the development of viral resistance pose additional limitations. The rapidly expanding field of nanotechnology has vast potential to radically advance the treatment and prevention of HIV/AIDS. Nanoparticles can provide improved drug delivery, by virtue of their small size, robustness, safety, multimodality or multifunctionality. Aims and objectives: Since HIV primarily infects CD4+ cells; we aim to use CD4 as a selectable target to deliver a pro-apoptotic protein to HIV-infected cells using nanoparticles as carriers. The aim of study was to develop a nanotechnology-based death inducing delivery system for the destruction of CD4+HIV infected cells through the activation of caspase-3. Methodology: A modified caspase-3 protein (Mut-3 was engineered, which is cleavable only by HIV-1 protease. Mut-3 can activate apoptosis in the presence of HIV-1 protease, consequently killing HIV-positive cells. Mut-3 protein was conjugated to gold nanoparticles together with a CD4-targeting peptide. The efficacy of the gold nanoparticles was tested on CHO cells that were genetically engineered to express GFP labelled CD4 and HIV-1 protease. Results: Mut-3 was expressed in bacterial cells and purified. CHO cells that stably over express CD4-GFP and HIV-1 protease were selected using Fluorescence Activated Cell Sorting. Dose response cell culture experiments showed that gold nanoparticles without Mut-3 and CD4-targeting peptide did not induce cell death in CHO cells, while gold nanoparticles that was conjugated with Mut-3 and the CD4-targeting peptide rapidly induced cell death in CHO cells. Conclusions: Our results suggest that gold nanoparticles conjugated

  16. Rationale for B cell targeting in SLE

    Science.gov (United States)

    Sanz, Iñaki

    2014-01-01

    B cells are central pathogenic players in Systemic Lupus Erythematosus and multiple other autoinmune diseases through antibody production as well as antibody independent functiona. At the same time, B cells are known to play important regulatory functions that may protect against autoimmune manifestations. Yet, the functional role of different B cell populations and their contribution to disease remain to be understood. The advent of agents that specifically target B cells, in particular anti-CD20 and ant-BLyS antibodies, have demonstrated the efficacy of this approach for the treatment of human autoimmunity. The analysis of patients treated with these and other B cell agents provide a unique opportunity to understand the correlates of clinical response and the significance of different B cell subsets. Here we discuss this information and how it could be used to better understand SLE and improve the rational design of B cell directed therapies in this disease. PMID:24763533

  17. Therapeutic Approaches to Target Cancer Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, Arlhee, E-mail: arlhee@cim.sld.cu; Leon, Kalet [Department of Systems Biology, Center of Molecular Immunology, 216 Street, PO Box 16040, Atabey, Havana 11600 (Cuba)

    2011-08-15

    The clinical relevance of cancer stem cells (CSC) remains a major challenge for current cancer therapies, but preliminary findings indicate that specific targeting may be possible. Recent studies have shown that these tumor subpopulations promote tumor angiogenesis through the increased production of VEGF, whereas the VEGF neutralizing antibody bevacizumab specifically inhibits CSC growth. Moreover, nimotuzumab, a monoclonal antibody against the epidermal growth factor receptor (EGFR) with a potent antiangiogenic activity, has been shown by our group to reduce the frequency of CSC-like subpopulations in mouse models of brain tumors when combined with ionizing radiation. These studies and subsequent reports from other groups support the relevance of approaches based on molecular-targeted therapies to selectively attack CSC. This review discusses the relevance of targeting both the EGFR and angiogenic pathways as valid approaches to this aim. We discuss the relevance of identifying better molecular markers to develop drug screening strategies that selectively target CSC.

  18. Cost targets for domestic fuel cell CHP

    Science.gov (United States)

    Staffell, I.; Green, R.; Kendall, K.

    Fuel cells have the potential to reduce domestic energy bills by providing both heat and power at the point of use, generating high value electricity from a low cost fuel. However, the cost of installing the fuel cell must be sufficiently low to be recovered by the savings made over its lifetime. A computer simulation is used to estimate the savings and cost targets for fuel cell CHP systems. Two pitfalls of this kind of simulation are addressed: the selection of representative performance figures for fuel cells, and the range of houses from which energy demand data was taken. A meta-study of the current state of the art is presented, and used with 102 house-years of demand to simulate the range of economic performance expected from four fuel cell technologies within the UK domestic CHP market. Annual savings relative to a condensing boiler are estimated at €170-300 for a 1 kWe fuel cell, giving a target cost of €350-625 kW -1 for any fuel cell technology that can demonstrate a 2.5-year lifetime. Increasing lifetime and reducing fuel cell capacity are identified as routes to accelerated market entry. The importance of energy demand is seen to outweigh both economic and technical performance assumptions, while manufacture cost and system lifetime are highlighted as the only significant differences between the technologies considered. SOFC are considered to have the greatest potential, but uncertainty in the assumptions used precludes any clear-cut judgement.

  19. Targeting regulatory T cells in cancer.

    LENUS (Irish Health Repository)

    Byrne, William L

    2012-01-31

    Infiltration of tumors by regulatory T cells confers growth and metastatic advantages by inhibiting antitumor immunity and by production of receptor activator of NF-kappaB (RANK) ligand, which may directly stimulate metastatic propagation of RANK-expressing cancer cells. Modulation of regulatory T cells can enhance the efficacy of cancer immunotherapy. Strategies include depletion, interference with function, inhibition of tumoral migration, and exploitation of T-cell plasticity. Problems with these strategies include a lack of specificity, resulting in depletion of antitumor effector T cells or global interruption of regulatory T cells, which may predispose to autoimmune diseases. Emerging technologies, such as RNA interference and tetramer-based targeting, may have the potential to improve selectivity and efficacy.

  20. Targeting cancer stem cells in hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    He AR

    2014-12-01

    Full Text Available Aiwu Ruth He,1 Daniel C Smith,1 Lopa Mishra2 1Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, 2Department of Gastroenterology, Hepatology, and Nutrition, The University of Texas MD Anderson Cancer Center, Houston, TX, USA Abstract: The poor outcome of patients with hepatocellular carcinoma (HCC is attributed to recurrence of the disease after curative treatment and the resistance of HCC cells to conventional chemotherapy, which may be explained partly by the function of liver cancer stem cells (CSCs. Liver CSCs have emerged as an important therapeutic target against HCC. Numerous surface markers for liver CSCs have been identified, and include CD133, CD90, CD44, CD13, and epithelial cell adhesion molecules. These surface markers serve not only as tools for identifying and isolating liver CSCs but also as therapeutic targets for eradicating these cells. In studies of animal models and large-scale genomic analyses of human HCC samples, many signaling pathways observed in normal stem cells have been found to be altered in liver CSCs, which accounts for the stemness and aggressive behavior of these cells. Antibodies and small molecule inhibitors targeting the signaling pathways have been evaluated at different levels of preclinical and clinical development. Another strategy is to promote the differentiation of liver CSCs to less aggressive HCC that is sensitive to conventional chemotherapy. Disruption of the tumor niche essential for liver CSC homeostasis has become a novel strategy in cancer treatment. To overcome the challenges in developing treatment for liver CSCs, more research into the genetic makeup of patient tumors that respond to treatment may lead to more effective therapy. Standardization of HCC CSC tumor markers would be helpful for measuring the CSC response to these agents. Herein, we review the current strategies for developing treatment to eradicate liver CSCs and to improve the outcome for patients with

  1. Targeted silver nanoparticles for ratiometric cell phenotyping

    Science.gov (United States)

    Willmore, Anne-Mari A.; Simón-Gracia, Lorena; Toome, Kadri; Paiste, Päärn; Kotamraju, Venkata Ramana; Mölder, Tarmo; Sugahara, Kazuki N.; Ruoslahti, Erkki; Braun, Gary B.; Teesalu, Tambet

    2016-04-01

    Affinity targeting is used to deliver nanoparticles to cells and tissues. For efficient targeting, it is critical to consider the expression and accessibility of the relevant receptors in the target cells. Here, we describe isotopically barcoded silver nanoparticles (AgNPs) as a tool for auditing affinity ligand receptors in cells. Tumor penetrating peptide RPARPAR (receptor: NRP-1) and tumor homing peptide GKRK (receptor: p32) were used as affinity ligands on the AgNPs. The binding and uptake of the peptide-functionalized AgNPs by cultured PPC-1 prostate cancer and M21 melanoma cells was dependent on the cell surface expression of the cognate peptide receptors. Barcoded peptide-functionalized AgNPs were synthesized from silver and palladium isotopes. The cells were incubated with a cocktail of the barcoded nanoparticles [RPARPAR (R), GKRK (K), and control], and cellular binding and internalization of each type of nanoparticle was assessed by inductively coupled plasma mass spectrometry. The results of isotopic analysis were in agreement with data obtained using optical methods. Using ratiometric measurements, we were able to classify the PPC-1 cell line as mainly NRP-1-positive, with 75 +/- 5% R-AgNP uptake, and the M21 cell line as only p32-positive, with 89 +/- 9% K-AgNP uptake. The isotopically barcoded multiplexed AgNPs are useful as an in vitro ratiometric phenotyping tool and have potential uses in functional evaluation of the expression of accessible homing peptide receptors in vivo.Affinity targeting is used to deliver nanoparticles to cells and tissues. For efficient targeting, it is critical to consider the expression and accessibility of the relevant receptors in the target cells. Here, we describe isotopically barcoded silver nanoparticles (AgNPs) as a tool for auditing affinity ligand receptors in cells. Tumor penetrating peptide RPARPAR (receptor: NRP-1) and tumor homing peptide GKRK (receptor: p32) were used as affinity ligands on the AgNPs. The

  2. Ion mediated targeting of cells with nanoparticles

    Science.gov (United States)

    Maheshwari, Vivek; Fu, Jinlong

    2010-03-01

    In eukaryotic cells, Ca^2+ ions are necessary for intracellular signaling, in activity of mitochondria and a variety of other cellular process that have been linked to cell apoptosis, proteins synthesis and cell-cycle regulation. Here we show that Ca^2+ ions, serving as the bio-compatible interface can be used to target Saccharomyces cerevisiae (SaC, baker's yeast), a model eukaryotic cell, with Au nanoparticles (10 nm). The Ca^2+ ions bind to the carboxylic acid groups in the citrate functionalized Au nanoparticles. This transforms the nanoparticles into micron long 1-D branched chain assemblies due to inter-particle dipole-dipole interaction and inter-particle bonding due to the divalent nature of the Ca^2+ ion. A similar transformation is observed with the use of divalent ions Mg^2+, Cd^2+ and Fe^2+. The 1-D assembly aids the interfacing of ion-nanoparticles on the cell by providing multiple contact points. Further monovalent ions such as Na^+ are also effective for the targeting of the cell with nanoparticles. However Na-Au nanoparticles are limited in their deposition as they exist in solution as single particles. The cells remain alive after the deposition process and their vitality is unaffected by the interfacing with ion-nanoparticles.

  3. Mast cell proteases as pharmacological targets.

    Science.gov (United States)

    Caughey, George H

    2016-05-05

    Mast cells are rich in proteases, which are the major proteins of intracellular granules and are released with histamine and heparin by activated cells. Most of these proteases are active in the granule as well as outside of the mast cell when secreted, and can cleave targets near degranulating mast cells and in adjoining tissue compartments. Some proteases released from mast cells reach the bloodstream and may have far-reaching actions. In terms of relative amounts, the major mast cell proteases include the tryptases, chymases, cathepsin G, carboxypeptidase A3, dipeptidylpeptidase I/cathepsin C, and cathepsins L and S. Some mast cells also produce granzyme B, plasminogen activators, and matrix metalloproteinases. Tryptases and chymases are almost entirely mast cell-specific, whereas other proteases, such as cathepsins G, C, and L are expressed by a variety of inflammatory cells. Carboxypeptidase A3 expression is a property shared by basophils and mast cells. Other proteases, such as mastins, are largely basophil-specific, although human basophils are protease-deficient compared with their murine counterparts. The major classes of mast cell proteases have been targeted for development of therapeutic inhibitors. Also, a human β-tryptase has been proposed as a potential drug itself, to inactivate of snake venins. Diseases linked to mast cell proteases include allergic diseases, such as asthma, eczema, and anaphylaxis, but also include non-allergic diseases such as inflammatory bowel disease, autoimmune arthritis, atherosclerosis, aortic aneurysms, hypertension, myocardial infarction, heart failure, pulmonary hypertension and scarring diseases of lungs and other organs. In some cases, studies performed in mouse models suggest protective or homeostatic roles for specific proteases (or groups of proteases) in infections by bacteria, worms and other parasites, and even in allergic inflammation. At the same time, a clearer picture has emerged of differences in the

  4. Targeting cell cycle regulators in hematologic malignancies

    Directory of Open Access Journals (Sweden)

    Eiman eAleem

    2015-04-01

    Full Text Available Hematologic malignancies represent the fourth most frequently diagnosed cancer in economically developed countries. In hematologic malignancies normal hematopoiesis is interrupted by uncontrolled growth of a genetically altered stem or progenitor cell (HSPC that maintains its ability of self-renewal. Cyclin-dependent kinases (CDKs not only regulate the mammalian cell cycle, but also influence other vital cellular processes, such as stem cell renewal, differentiation, transcription, epigenetic regulation, apoptosis, and DNA repair. Chromosomal translocations, amplification, overexpression and altered CDK activities have been described in different types of human cancer, which have made them attractive targets for pharmacological inhibition. Mouse models deficient for one or more CDKs have significantly contributed to our current understanding of the physiological functions of CDKs, as well as their roles in human cancer. The present review focuses on selected cell cycle kinases with recent emerging key functions in hematopoiesis and in hematopoietic malignancies, such as CDK6 and its role in MLL-rearranged leukemia and acute lymphocytic leukemia, CDK1 and its regulator WEE-1 in acute myeloid leukemia, and cyclin C/CDK8/CDK19 complexes in T-cell acute lymphocytic leukemia. The knowledge gained from gene knockout experiments in mice of these kinases is also summarized. An overview of compounds targeting these kinases, which are currently in clinical development in various solid tumors and hematopoietic malignances, is presented. These include the CDK4/CDK6 inhibitors (palbociclib, LEE011, LY2835219, pan-CDK inhibitors that target CDK1 (dinaciclib, flavopiridol, AT7519, TG02, P276-00, terampeprocol and RGB 286638 as well as the WEE-1 kinase inhibitor, MK-1775. The advantage of combination therapy of cell cycle inhibitors with conventional chemotherapeutic agents used in the treatment of AML, such as cytarabine, is discussed.

  5. Targeting the osteosarcoma cancer stem cell

    Directory of Open Access Journals (Sweden)

    Qin Ling

    2010-10-01

    Full Text Available Abstract Osteosarcoma is the most common type of solid bone cancer and the second leading cause of cancer-related death in pediatric patients. Many patients are not cured by the current osteosarcoma therapy consisting of combination chemotherapy along with surgery and thus new treatments are urgently needed. In the last decade, cancer stem cells have been identified in many tumors such as leukemia, brain, breast, head and neck, colon, skin, pancreatic, and prostate cancers and these cells are proposed to play major roles in drug resistance, tumor recurrence, and metastasis. Recent studies have shown evidence that osteosarcoma also possesses cancer stem cells. This review summarizes the current knowledge about the osteosarcoma cancer stem cell including the methods used for its isolation, its properties, and its potential as a new target for osteosarcoma treatment.

  6. Structural Insights into the Calcium-Mediated Allosteric Transition in the C-Terminal Domain of Calmodulin from Nuclear Magnetic Resonance Measurements.

    Science.gov (United States)

    Kukic, Predrag; Lundström, Patrik; Camilloni, Carlo; Evenäs, Johan; Akke, Mikael; Vendruscolo, Michele

    2016-01-12

    Calmodulin is a two-domain signaling protein that becomes activated upon binding cooperatively two pairs of calcium ions, leading to large-scale conformational changes that expose its binding site. Despite significant advances in understanding the structural biology of calmodulin functions, the mechanistic details of the conformational transition between closed and open states have remained unclear. To investigate this transition, we used a combination of molecular dynamics simulations and nuclear magnetic resonance (NMR) experiments on the Ca(2+)-saturated E140Q C-terminal domain variant. Using chemical shift restraints in replica-averaged metadynamics simulations, we obtained a high-resolution structural ensemble consisting of two conformational states and validated such an ensemble against three independent experimental data sets, namely, interproton nuclear Overhauser enhancements, (15)N order parameters, and chemical shift differences between the exchanging states. Through a detailed analysis of this structural ensemble and of the corresponding statistical weights, we characterized a calcium-mediated conformational transition whereby the coordination of Ca(2+) by just one oxygen of the bidentate ligand E140 triggers a concerted movement of the two EF-hands that exposes the target binding site. This analysis provides atomistic insights into a possible Ca(2+)-mediated activation mechanism of calmodulin that cannot be achieved from static structures alone or from ensemble NMR measurements of the transition between conformations.

  7. Targeting the acute myeloid leukemia stem cells.

    Science.gov (United States)

    Krause, Alexandre; Luciana, M; Krause, Fontanari; Rego, Eduardo M

    2010-02-01

    The idea that within the bulk of leukemic cells there are immature progenitors which are intrinsically resistant to chemotherapy and able to repopulate the tumor after treatment is not recent. Nevertheless, the term leukemia stem cells (LSCs) has been adopted recently to describe these immature progenitors based on the fact that they share the most relevant features of the normal hematopoetic stem cells (HSCs), i.e. the self-renewal potential and quiescent status. LSCs differ from their normal counterparts and from the more differentiated leukemic cells regarding the default status of pathways regulating apoptosis, cell cycle, telomere maintenance and transport pumps activity. In addition, unique features regarding the interaction of these cells with the microenvironment have been characterized. Therapeutic strategies targeting these unique features are at different stages of development but the reported results are promising. The aim of this review is, by taking acute myeloid leukemia (AML) as a bona fide example, to discuss some of the mechanisms used by the LSCs to survive and the strategies which could be used to eradicate these cells.

  8. Therapeutic strategies for targeting cancer stem cells

    Institute of Scientific and Technical Information of China (English)

    Yu Jeong Kim; Elizabeth L Siegler; Natnaree Siriwon; Pin Wang

    2016-01-01

    The therapeutic limitations of conventional chemotherapeutic drugs present a challenge for cancer therapy; these shortcomings are largely attributed to the ability of cancer cells to repopulate and metastasize after initial therapies. Compelling evidence suggests that cancer stem cells (CSCs) have a crucial impact in current shortcomings of cancer therapy because they are largely responsible for tumor initiation, relapse, metastasis, and chemo-resistance. Thus, a better understanding of the properties and mechanisms underlying CSC resistance to treatments is necessary to improve patient outcomes and survival rates. In this review, the authors characterize and compare different CSC-speciifc biomarkers that are present in various types of tumors. We further discuss multiple targeting approaches currently in preclinical or clinical testing that show great potential for targeting CSCs. This review discusses numerous strategies to eliminate CSCs by targeting surface biomarkers, regulating CSC-associated oncogenes and signaling pathways, inhibiting drug-eflfux pumps involved in drug resistance, modulating the tumor microenvironment and immune system, and applying drug combination therapy using nanomedicine.

  9. Cancer Stem Cells: A Moving Target.

    Science.gov (United States)

    Francipane, Maria Giovanna; Chandler, Julie; Lagasse, Eric

    2013-06-01

    Even though the number of anti-cancer drugs entering clinical trials and approved by the FDA has increased in recent years, many cancer patients still experience poor survival outcome. The main explanation for such a dismal prognosis is that current therapies might leave behind a population of cancer cells with the capacity for long-term self-renewal, so-called cancer stem cells (CSCs), from which most tumors are believed to be derived and fueled. CSCs might favor local and distant recurrence even many years after initial treatment, thus representing a potential target for therapies aimed at improving clinical outcome. In this review, we will address the CSC hypothesis with a particular emphasis on its current paradigms and debates, and discuss several mechanisms of CSC resistance to conventional therapies.

  10. Engineering novel cell surface chemistry for selective tumor cell targeting

    Energy Technology Data Exchange (ETDEWEB)

    Bertozzi, C.R. [Univ. of California, Berkeley, CA (United States)]|[Lawrence Berkeley National Lab., CA (United States)

    1997-12-31

    A common feature of many different cancers is the high expression level of the two monosaccharides sialic acid and fucose within the context of cell-surface associated glycoconjugates. A correlation has been made between hypersialylation and/or hyperfucosylation and the highly metastatic phenotype. Thus, a targeting strategy based on sialic acid or fucose expression would be a powerful tool for the development of new cancer cell-selective therapies and diagnostic agents. We have discovered that ketone groups can be incorporated metabolically into cell-surface associated sialic acids. The ketone is can be covalently ligated with hydrazide functionalized proteins or small molecules under physiological conditions. Thus, we have discovered a mechanism to selectively target hydrazide conjugates to highly sialylated cells such as cancer cells. Applications of this technology to the generation of novel cancer cell-selective toxins and MRI contrast reagents will be discussed, in addition to progress towards the use of cell surface fucose residues as vehicles for ketone expression.

  11. Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

    Science.gov (United States)

    Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

    2000-04-01

    Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy.

  12. M cell targeting by a Claudin 4 targeting peptide can enhance mucosal IgA responses

    Directory of Open Access Journals (Sweden)

    Lo David D

    2012-03-01

    Full Text Available Abstract Background Mucosal immune surveillance is thought to be largely achieved through uptake by specialized epithelial M cells. We recently identified Claudin 4 as an M cell target receptor and developed a Claudin 4 targeting peptide (CPE that can mediate uptake of nanoparticles through Nasal Associated Lymphoid Tissue (NALT M cells. Methods Recombinant influenza hemagglutinin (HA and a version with the CPE peptide at the C-terminal end was used to immunize mice by the intranasal route along with a single dose of cholera toxin as an adjuvant. Serum and mucosal IgG and IgA responses were tested for reactivity to HA. Results We found that the recombinant HA was immunogenic on intranasal administration, and inclusion of the CPE targeting peptide induced higher mucosal IgA responses. This mucosal administration also induced systemic serum IgG responses with Th2 skewing, but targeting did not enhance IgG responses, suggesting that the IgG response to mucosal immunization is independent of the effects of CPE M cell targeting. Conclusions M cell targeting mediated by a Claudin 4-specific targeting peptide can enhance mucosal IgA responses above the response to non-targeted mucosal antigen. Since Claudin 4 has also been found to be regulated in human Peyer's patch M cells, the CPE targeting peptide could be a reasonable platform delivery technology for mucosal vaccination.

  13. Kaposi's sarcoma associated herpesvirus (KSHV entry into target cells

    Directory of Open Access Journals (Sweden)

    Sayan eChakraborty

    2012-01-01

    Full Text Available Herpesvirus infection of target cells is a complex process involving multiple host cell surface molecules (receptors and multiple viral envelope glycoproteins. Kaposi’s sarcoma associated herpesvirus (KSHV or HHV-8 infects a variety of in vivo target cells such as endothelial cells, B cells, monocytes, epithelial cells, and keratinocytes. KSHV also infects a diversity of in vitro target cells and establishes in vitro latency in many of these cell types. KSHV interactions with the host cell surface molecules and its mode of entry in the various target cells are critical for the understanding of KSHV pathogenesis. KSHV is the first herpesvirus shown to interact with adherent target cell integrins and this interaction initiates the host cell pre-existing signal pathways that are utilized for successful infection. This chapter discusses the various aspects of the early stage of KSHV infection of target cells, receptors used and issues that need to be clarified and future directions. The various signaling events triggered by KSHV infection and the potential role of signaling events in the different stages of infection are summarized providing the framework and starting point for further detailed studies essential to fully comprehend the pathogenesis of KSHV.

  14. Cell-targeting aptamers act as intracellular delivery vehicles.

    Science.gov (United States)

    Gopinath, Subash C B; Lakshmipriya, Thangavel; Chen, Yeng; Arshad, M K Md; Kerishnan, Jesinda P; Ruslinda, A R; Al-Douri, Yarub; Voon, C H; Hashim, Uda

    2016-08-01

    Aptamers are single-stranded nucleic acids or peptides identified from a randomized combinatorial library through specific interaction with the target of interest. Targets can be of any size, from small molecules to whole cells, attesting to the versatility of aptamers for binding a wide range of targets. Aptamers show drug properties that are analogous to antibodies, with high specificity and affinity to their target molecules. Aptamers can penetrate disease-causing microbial and mammalian cells. Generated aptamers that target surface biomarkers act as cell-targeting agents and intracellular delivery vehicles. Within this context, the "cell-internalizing aptamers" are widely investigated via the process of cell uptake with selective binding during in vivo systematic evolution of ligands by exponential enrichment (SELEX) or by cell-internalization SELEX, which targets cell surface antigens to be receptors. These internalizing aptamers are highly preferable for the localization and functional analyses of multiple targets. In this overview, we discuss the ways by which internalizing aptamers are generated and their successful applications. Furthermore, theranostic approaches featuring cell-internalized aptamers are discussed with the purpose of analyzing and diagnosing disease-causing pathogens.

  15. Human immune cell targeting of protein nanoparticles - caveospheres

    Science.gov (United States)

    Glass, Joshua J.; Yuen, Daniel; Rae, James; Johnston, Angus P. R.; Parton, Robert G.; Kent, Stephen J.; de Rose, Robert

    2016-04-01

    Nanotechnology has the power to transform vaccine and drug delivery through protection of payloads from both metabolism and off-target effects, while facilitating specific delivery of cargo to immune cells. However, evaluation of immune cell nanoparticle targeting is conventionally restricted to monocultured cell line models. We generated human caveolin-1 nanoparticles, termed caveospheres, which were efficiently functionalized with monoclonal antibodies. Using this platform, we investigated CD4+ T cell and CD20+ B cell targeting within physiological mixtures of primary human blood immune cells using flow cytometry, imaging flow cytometry and confocal microscopy. Antibody-functionalization enhanced caveosphere binding to targeted immune cells (6.6 to 43.9-fold) within mixed populations and in the presence of protein-containing fluids. Moreover, targeting caveospheres to CCR5 enabled caveosphere internalization by non-phagocytic CD4+ T cells--an important therapeutic target for HIV treatment. This efficient and flexible system of immune cell-targeted caveosphere nanoparticles holds promise for the development of advanced immunotherapeutics and vaccines.

  16. Patient-Derived Antibody Targets Tumor Cells

    Science.gov (United States)

    An NCI Cancer Currents blog on an antibody derived from patients that killed tumor cells in cell lines of several cancer types and slowed tumor growth in mouse models of brain and lung cancer without evidence of side effects.

  17. Targeting Quiescent Cancer Cells to Eliminate Tumor Recurrence After Therapy

    Science.gov (United States)

    2015-10-01

    AD_________________ (Leave blank) Award Number: W81XWH-14-1-0350 TITLE: Targeting Quiescent Cancer Cells to Eliminate Tumor Recurrence After...30 Sep 2014 - 29 Sep 2015 4. TITLE AND SUBTILE Targeting Quiescent Cancer Cells to Eliminate Tumor Recurrence After Therapy 5a. CONTRACT NUMBER...Innovative reporter gene systems are designed to mark quiescent or proliferating lung cancer cells (Aim 1) and then used to track and trace the dynamics of

  18. Double-strand breaks at the target locus stimulate gene targeting in embryonic stem cells.

    Science.gov (United States)

    Smih, F; Rouet, P; Romanienko, P J; Jasin, M

    1995-01-01

    Double-strand breaks (DSBs) are recombinogenic lesions in chromosomal DNA in yeast, Drosophila and Caenorhabditis elegans. Recent studies in mammalian cells utilizing the I-Scel endonuclease have demonstrated that in some immortalized cell lines DSBs in chromosomal DNA are also recombinogenic. We have now tested embryonic stem (ES) cells, a non-transformed mouse cell line frequently used in gene targeting studies. We find that a DSB introduced by I-Scel stimulates gene targeting at a selectable neo locus at least 50-fold. The enhanced level of targeting is achieved by transient expression of the I-Scel endonuclease. In 97% of targeted clones a single base pair polymorphism in the transfected homologous fragment was incorporated into the target locus. Analysis of the targeted locus demonstrated that most of the homologous recombination events were 'two-sided', in contrast to previous studies in 3T3 cells in which 'one-sided' homologous events predominated. Thus ES cells may be more faithful in incorporating homologous fragments into their genome than other cells in culture. Images PMID:8559659

  19. Buoyancy-activated cell sorting using targeted biotinylated albumin microbubbles.

    Directory of Open Access Journals (Sweden)

    Yu-Ren Liou

    Full Text Available Cell analysis often requires the isolation of certain cell types. Various isolation methods have been applied to cell sorting, including fluorescence-activated cell sorting and magnetic-activated cell sorting. However, these conventional approaches involve exerting mechanical forces on the cells, thus risking cell damage. In this study we applied a novel isolation method called buoyancy-activated cell sorting, which involves using biotinylated albumin microbubbles (biotin-MBs conjugated with antibodies (i.e., targeted biotin-MBs. Albumin MBs are widely used as contrast agents in ultrasound imaging due to their good biocompatibility and stability. For conjugating antibodies, biotin is conjugated onto the albumin MB shell via covalent bonds and the biotinylated antibodies are conjugated using an avidin-biotin system. The albumin microbubbles had a mean diameter of 2 μm with a polydispersity index of 0.16. For cell separation, the MDA-MB-231 cells are incubated with the targeted biotin-MBs conjugated with anti-CD44 for 10 min, centrifuged at 10 g for 1 min, and then allowed 1 hour at 4 °C for separation. The results indicate that targeted biotin-MBs conjugated with anti-CD44 antibodies can be used to separate MDA-MB-231 breast cancer cells; more than 90% of the cells were collected in the MB layer when the ratio of the MBs to cells was higher than 70:1. Furthermore, we found that the separating efficiency was higher for targeted biotin-MBs than for targeted avidin-incorporated albumin MBs (avidin-MBs, which is the most common way to make targeted albumin MBs. We also demonstrated that the recovery rate of targeted biotin-MBs was up to 88% and the sorting purity was higher than 84% for a a heterogenous cell population containing MDA-MB-231 cells (CD44(+ and MDA-MB-453 cells (CD44-, which are classified as basal-like breast cancer cells and luminal breast cancer cells, respectively. Knowing that the CD44(+ is a commonly used cancer-stem-cell

  20. Mesenchymal stem cells targeting the GVHD

    Institute of Scientific and Technical Information of China (English)

    WANG Liang; ZHAO Robert ChunHua

    2009-01-01

    Acute graft-versus-host disease (GVHD) occurs after allogeneic hematopoietic stem cell transplant and is a reaction of donor immune cells against host tissues. About 35% -5% of hematopoietic stem cell transplant (HSCT) recipients will develop acute GVHD. It is associated with considerable morbidity and mortality, particularly in patients who do not respond to primary therapy, which usually consists of glucocorticoids(steroids). Most of the available second-line and third-line treatments for sterold-refractory acute GVHD induce severe immunodeficiency, which is commonly accompanied by lethal infectious complications. Mesenchymal stem cells (MSCs) have been shown to mediate immunomodulatory effects. The recently elucidated immunosuppreseive potential of mesenchymal stem cells has set the stage for their clinical testing as cellular immunosuppressants, MSCs have been used in patients with steroid-refractory acute GVHD, and encouraging responses have been obtained in many studies. The utility of MSCs for the treatment of GVHD is becoming clear.

  1. Glial cells as drug targets : What does it take?

    NARCIS (Netherlands)

    Moller, Thomas; Boddeke, Hendrikus W. G. M.

    2016-01-01

    The last two decades have brought a significant increase in our understanding of glial biology and glial contribution to CNS disease. Yet, despite the fact that glial cells make up the majority of CNS cells, no drug specifically targeting glial cells is on the market. Given the long development time

  2. Identification of novel Notch target genes in T cell leukaemia

    Directory of Open Access Journals (Sweden)

    Warrander Fiona

    2009-06-01

    Full Text Available Abstract Background Dysregulated Notch signalling is believed to play an important role in the development and maintenance of T cell leukaemia. At a cellular level, Notch signalling promotes proliferation and inhibits apoptosis of T cell acute lymphoblastic leukaemia (T-ALL cells. In this study we aimed to identify novel transcriptional targets of Notch signalling in the T-ALL cell line, Jurkat. Results RNA was prepared from Jurkat cells retrovirally transduced with an empty vector (GFP-alone or vectors containing constitutively active forms of Notch (N1ΔE or N3ΔE, and used for Affymetrix microarray analysis. A subset of genes found to be regulated by Notch was chosen for real-time PCR validation and in some cases, validation at the protein level, using several Notch-transduced T-ALL and non-T-ALL leukaemic cell lines. As expected, several known transcriptional target of Notch, such as HES1 and Deltex, were found to be overexpressed in Notch-transduced cells, however, many novel transcriptional targets of Notch signalling were identified using this approach. These included the T cell costimulatory molecule CD28, the anti-apoptotic protein GIMAP5, and inhibitor of DNA binding 1 (1D1. Conclusion The identification of such downstream Notch target genes provides insights into the mechanisms of Notch function in T cell leukaemia, and may help identify novel therapeutic targets in this disease.

  3. Modeling Natural Killer Cell Targeted Immunotherapies

    Science.gov (United States)

    Lopez-Lastra, Silvia; Di Santo, James P.

    2017-01-01

    Animal models have extensively contributed to our understanding of human immunobiology and to uncover the underlying pathological mechanisms occurring in the development of diseases. However, mouse models do not reproduce the genetic and molecular complexity inherent in human disease conditions. Human immune system (HIS) mouse models that are susceptible to human pathogens and can recapitulate human hematopoiesis and tumor immunobiology provide one means to bridge the interspecies gap. Natural killer cells are the founding member of the innate lymphoid cell family. They exert a rapid and strong immune response against tumor and pathogen-infected cells. Their antitumor features have long been exploited for therapeutic purposes in the context of cancer. In this review, we detail the development of highly immunodeficient mouse strains and the models currently used in cancer research. We summarize the latest improvements in adoptive natural killer (NK) cell therapies and the development of novel NK cell sources. Finally, we discuss the advantages of HIS mice to study the interactions between human NK cells and human cancers and to develop new therapeutic strategies.

  4. Targeting DNA vaccines to myeloid cells using a small peptide.

    Science.gov (United States)

    Ye, Chunting; Choi, Jang Gi; Abraham, Sojan; Shankar, Premlata; Manjunath, N

    2015-01-01

    Targeting DNA vaccines to dendritic cells (DCs) greatly enhances immunity. Although several approaches have been used to target protein Ags to DCs, currently there is no method that targets DNA vaccines directly to DCs. Here, we show that a small peptide derived from the rabies virus glycoprotein fused to protamine residues (RVG-P) can target DNA to myeloid cells, including DCs, which results in enhanced humoral and T-cell responses. DCs targeted with a DNA vaccine encoding the immunodominant vaccinia B8R gene via RVG-P were able to restimulate vaccinia-specific memory T cells in vitro. Importantly, a single i.v. injection of B8R gene bound to RVG-P was able to prime a vaccinia-specific T-cell response that was able to rapidly clear a subsequent vaccinia challenge in mice. Moreover, delivery of DNA in DCs was enough to induce DC maturation and efficient Ag presentation without the need for adjuvants. Finally, immunization of mice with a DNA-vaccine encoding West Nile virus (WNV) prM and E proteins via RVG-P elicited high titers of WNV-neutralizing Abs that protected mice from lethal WNV challenge. Thus, RVG-P provides a reagent to target DNA vaccines to myeloid cells and elicit robust T-cell and humoral immune responses.

  5. Coating nanoparticles with cell membranes for targeted drug delivery.

    Science.gov (United States)

    Gao, Weiwei; Zhang, Liangfang

    2015-01-01

    Targeted delivery allows drug molecules to preferentially accumulate at the sites of action and thus holds great promise to improve therapeutic index. Among various drug-targeting approaches, nanoparticle-based delivery systems offer some unique strengths and have achieved exciting preclinical and clinical results. Herein, we aim to provide a review on the recent development of cell membrane-coated nanoparticle system, a new class of biomimetic nanoparticles that combine both the functionalities of cellular membranes and the engineering flexibility of synthetic nanomaterials for effective drug delivery and novel therapeutics. This review is particularly focused on novel designs of cell membrane-coated nanoparticles as well as their underlying principles that facilitate the purpose of drug targeting. Three specific areas are highlighted, including: (i) cell membrane coating to prolong nanoparticle circulation, (ii) cell membrane coating to achieve cell-specific targeting and (iii) cell membrane coating for immune system targeting. Overall, cell membrane-coated nanoparticles have emerged as a novel class of targeted nanotherapeutics with strong potentials to improve on drug delivery and therapeutic efficacy for treatment of various diseases.

  6. Targeting Strategies for Renal Cell Carcinoma: From Renal Cancer Cells to Renal Cancer Stem Cells.

    Science.gov (United States)

    Yuan, Zhi-Xiang; Mo, Jingxin; Zhao, Guixian; Shu, Gang; Fu, Hua-Lin; Zhao, Wei

    2016-01-01

    Renal cell carcinoma (RCC) is a common form of urologic tumor that originates from the highly heterogeneous epithelium of renal tubules. Over the last decade, targeting therapies to renal cancer cells have transformed clinical care for RCC. Recently, it was proposed that renal cancer stem cells (CSCs) isolated from renal carcinomas were responsible for driving tumor growth and resistance to conventional chemotherapy and radiotherapy, according to the theory of CSCs; this has provided the rationale for therapies targeting this aggressive cell population. Precise identification of renal CSC populations and the complete cell hierarchy will accurately inform characterization of disease subtypes. This will ultimately contribute to more personalized and targeted therapies. Here, we summarize potential targeting strategies for renal cancer cells and renal CSCs, including tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors (mTOR), interleukins, CSC marker inhibitors, bone morphogenetic protein-2, antibody drug conjugates, and nanomedicine. In conclusion, targeting therapies for RCC represent new directions for exploration and clinical investigation and they plant a seed of hope for advanced clinical care.

  7. The most promising strategy targeted against cancer stem cells

    Institute of Scientific and Technical Information of China (English)

    LIN Zhi-xiong; YANG Li-juan; ZHEN Shi-ming

    2011-01-01

    To the Editor:We read with great enthusiasm an interesting and exciting review article Targeting glioma stem cells:enough to terminate gliomagenesis? by Dong and Huang,1 who believed that single targeting therapy against glioma stem cells is unsuccessful and ameliorating the local tumor inducing/promoting microenvironment should be a reasonable strategy.Our group is enduringly engaged in the study of glioma,and we also put much concern upon the research of tumor microecosystem (TMES).In fact,the targeting therapy against cancer stem cells (CSCs) involves two aspects.One is the marked molecular target against CSCs.The other is how to deal with CSCs,by cytotoxic against CSCs,or inducing tumor stem cells to differentiate,or others?

  8. Calcium-Mediated Regulation of Proton-Coupled Sodium Transport - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Schumaker, Karen S [Professor

    2013-10-24

    The long-term goal of our experiments was to understand mechanisms that regulate energy coupling by ion currents in plants. Activities of living organisms require chemical, mechanical, osmotic or electrical work, the energy for which is supplied by metabolism. Adenosine triphosphate (ATP) has long been recognized as the universal energy currency, with metabolism supporting the synthesis of ATP and the hydrolysis of ATP being used for the subsequent work. However, ATP is not the only energy currency in living organisms. A second and very different energy currency links metabolism to work by the movement of ions passing from one side of a membrane to the other. These ion currents play a major role in energy capture and they support a range of physiological processes from the active transport of nutrients to the spatial control of growth and development. In Arabidopsis thaliana (Arabidopsis), the activity of a plasma membrane Na+/H+ exchanger, SALT OVERLY SENSITIVE1 (SOS1), is essential for regulation of sodium ion homeostasis during plant growth in saline conditions. Mutations in SOS1 result in severely reduced seedling growth in the presence of salt compared to the growth of wild type. SOS1 is a secondary active transporter coupling movement of sodium ions out of the cell using energy stored in the transplasma membrane proton gradient, thereby preventing the build-up of toxic levels of sodium in the cytosol. SOS1 is regulated by complexes containing the SOS2 and CALCINEURIN B-LIKE10 (CBL10) or SOS3 proteins. CBL10 and SOS3 (also identified as CBL4) encode EF-hand calcium sensors that interact physically with and activate SOS2, a serine/threonine protein kinase. The CBL10/SOS2 or SOS3/SOS2 complexes then activate SOS1 Na+/H+ exchange activity. We completed our studies to understand how SOS1 activity is regulated. Specifically, we asked: (1) how does CBL10 regulate SOS1 activity? (2) What role do two putative CBL10-interacting proteins play in SOS1 regulation? (3) Are

  9. Mesenchymal stem cells targeting the GVHD

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Robert; ChunHua

    2009-01-01

    Acute graft-versus-host disease(GVHD) occurs after allogeneic hematopoietic stem cell transplant and is a reaction of donor immune cells against host tissues.About 35%-50% of hematopoietic stem cell transplant(HSCT) recipients will develop acute GVHD.It is associated with considerable morbidity and mortality,particularly in patients who do not respond to primary therapy,which usually consists of glucocorticoids(steroids).Most of the available second-line and third-line treatments for steroid-refractory acute GVHD induce severe immunodeficiency,which is commonly accompanied by lethal infectious complications.Mesenchymal stem cells(MSCs) have been shown to mediate immunomodulatory effects.The recently elucidated immunosuppressive potential of mesenchymal stem cells has set the stage for their clinical testing as cellular immunosuppressants,MSCs have been used in patients with steroid-refractory acute GVHD,and encouraging responses have been obtained in many studies.The utility of MSCs for the treatment of GVHD is becoming clear.

  10. Targeting the bone marrow: applications in stem cell transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Orchard, K. [Southampton University Hospital Trust, Southampton (United Kingdom). Department of Haematology; Cooper, M. [St. Bartholomew' s Hospital, London (United Kingdom). Pharmacy Department

    2004-12-01

    Therapeutic doses of radiation cab be selectively directed to the bone marrow either directly using vectors that bind to myeloid and/or lymphoid specific antigens or indirectly by targeting bone matrix. The combination of an accessible target tissue and relatively radiation sensitive malignant cells favours the use of targeted radiotherapy in the treatment of haematopoietic malignancies. Dose escalation of targeted radiation can increase tumour cell destruction and has led to the use of myelosuppressive and possibly myeloablative doses of targeted radiation. A natural development has been the use of targeted radiation in conditioning prior to haematopoietic stem cell transplantation (HSCT). Several groups are actively exploring the use of targeted radiotherapy in the context of HSCT as treatment for haematological malignancies. Although no randomised trials using targeted radiotherapy in HSCT have been published, phase I and II trials have shown very encouraging results stimulating further clinical research in this field. After more than a decade of translational research the optimal combination of therapeutic radioisotope and vector has not been determined. This review summarises the clinical experience of targeted radiotherapy in HSCT and discusses the problems that still need to be solved to maximise the potential of this new treatment modality in HSCT.

  11. [Advances of molecular targeted therapy in squamous cell lung cancer].

    Science.gov (United States)

    Ma, Li; Zhang, Shucai

    2013-12-01

    Squamous cell lung cancer (SQCLC) is one of the most prevalent subtypes of lung cancer worldwide, about 400,000 persons die from squamous-cell lung cancer around the world, and its pathogenesis is closely linked with tobacco exposure. Unfortunately, squamous-cell lung cancer patients do not benefit from major advances in the development of targeted therapeutics such as epidermal growth factor receptor (EGFR) inhibitors or anaplastic lymphoma kinase (ALK) inhibitors that show exquisite activity in lung adenocarcinomas with EGFR mutations or echinoderm microtubule associated protein like-4 (EML4)-ALK fusions, respectively. Major efforts have been launched to characterize the genomes of squamous-cell lung cancers. Among the new results emanating from these efforts are amplifications of the fibroblast growth factor receptor 1 (FGFR1) gene, the discoidin domain receptor 2 (DDR2) gene mutation as potential novel targets for the treatment of SQCLCs. Researchers find that there are many specific molecular targeted genes in the genome of squamous-cell lung cancer patients. These changes play a vital role in cell cycle regulation, oxidative stress, cell apoptosis, squamous epithelium differentiation, may be the candidate targeted moleculars in SQCLCs. Here, we provide a review on these discoveries and their implications for clinical trials in squamous-cell lung cancer assessing the value of novel therapeutics addressing these targets.

  12. Advances of Molecular Targeted Therapy in Squamous Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Li MA

    2013-12-01

    Full Text Available Squamous cell lung cancer (SQCLC is one of the most prevalent subtypes of lung cancer worldwide, about 400,000 persons die from squamous-cell lung cancer around the world, and its pathogenesis is closely linked with tobacco exposure. Unfortunately, squamous-cell lung cancer patients do not benefit from major advances in the development of targeted therapeutics such as epidermal growth factor receptor (EGFR inhibitors or anaplastic lymphoma kinase (ALK inhibitors that show exquisite activity in lungadenocarcinomas with EGFR mutations or echinoderm microtubule associated protein like-4 (EML4-ALK fusions, respectively. Major efforts have been launched to characterize the genomes of squamous-cell lung cancers. Among the new results emanating from these efforts are amplifications of the fibroblast growth factor receptor 1 (FGFR1 gene, the discoidin domain receptor 2 (DDR2 gene mutation as potential novel targets for the treatment of SQCLCs. Researchers find that there are many specific molecular targeted genes in the genome of squamous-cell lung cancer patients. These changes play a vital role in cell cycle regulation, oxidative stress, cell apoptosis, squamous epithelium differentiation, may be the candidate targeted moleculars in SQCLCs. Here, we provide a review on these discoveries and their implications for clinical trials in squamous-cell lungcancer assessing the value of novel therapeutics addressing these targets.

  13. Targeted cellular ablation based on the morphology of malignant cells

    Science.gov (United States)

    Ivey, Jill W.; Latouche, Eduardo L.; Sano, Michael B.; Rossmeisl, John H.; Davalos, Rafael V.; Verbridge, Scott S.

    2015-11-01

    Treatment of glioblastoma multiforme (GBM) is especially challenging due to a shortage of methods to preferentially target diffuse infiltrative cells, and therapy-resistant glioma stem cell populations. Here we report a physical treatment method based on electrical disruption of cells, whose action depends strongly on cellular morphology. Interestingly, numerical modeling suggests that while outer lipid bilayer disruption induced by long pulses (~100 μs) is enhanced for larger cells, short pulses (~1 μs) preferentially result in high fields within the cell interior, which scale in magnitude with nucleus size. Because enlarged nuclei represent a reliable indicator of malignancy, this suggested a means of preferentially targeting malignant cells. While we demonstrate killing of both normal and malignant cells using pulsed electric fields (PEFs) to treat spontaneous canine GBM, we proposed that properly tuned PEFs might provide targeted ablation based on nuclear size. Using 3D hydrogel models of normal and malignant brain tissues, which permit high-resolution interrogation during treatment testing, we confirmed that PEFs could be tuned to preferentially kill cancerous cells. Finally, we estimated the nuclear envelope electric potential disruption needed for cell death from PEFs. Our results may be useful in safely targeting the therapy-resistant cell niches that cause recurrence of GBM tumors.

  14. Surface-modified gold nanorods for specific cell targeting

    Science.gov (United States)

    Wang, Chan-Ung; Arai, Yoshie; Kim, Insun; Jang, Wonhee; Lee, Seonghyun; Hafner, Jason H.; Jeoung, Eunhee; Jung, Deokho; Kwon, Youngeun

    2012-05-01

    Gold nanoparticles (GNPs) have unique properties that make them highly attractive materials for developing functional reagents for various biomedical applications including photothermal therapy, targeted drug delivery, and molecular imaging. For in vivo applications, GNPs need to be prepared with very little or negligible cytotoxicitiy. Most GNPs are, however, prepared using growth-directing surfactants such as cetyl trimethylammonium bromide (CTAB), which are known to have considerable cytotoxicity. In this paper, we describe an approach to remove CTAB to a non-toxic concentration. We optimized the conditions for surface modification with methoxypolyethylene glycol thiol (mPEG), which replaced CTAB and formed a protective layer on the surface of gold nanorods (GNRs). The cytotoxicities of pristine and surface-modified GNRs were measured in primary human umbilical vein endothelial cells and human cell lines derived from hepatic carcinoma cells, embryonic kidney cells, and thyroid papillary carcinoma cells. Cytotoxicity assays revealed that treating cells with GNRs did not significantly affect cell viability except for thyroid papillary carcinoma cells. Thyroid cancer cells were more susceptible to residual CTAB, so CTAB had to be further removed by dialysis in order to use GNRs for thyroid cell targeting. PEGylated GNRs are further modified to present monoclonal antibodies that recognize a specific surface marker, Na-I symporter, for thyroid cells. Antibody-conjugated GNRs specifically targeted human thyroid cells in vitro.

  15. Therapeutic strategies targeting B-cells in multiple sclerosis.

    Science.gov (United States)

    Milo, Ron

    2016-07-01

    Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system (CNS) that traditionally has been considered to be mediated primarily by T-cells. Increasing evidence, however, suggests the fundamental role of B-cells in the pathogenesis of the disease. Recent strategies targeting B-cells in MS have demonstrated impressive and sometimes surprising results: B-cell depletion by monoclonal antibodies targeting the B-cell surface antigen CD20 (e.g. rituximab, ocrelizumab, ofatumumab) was shown to exert profound anti-inflammatory effect in MS with favorable risk-benefit ratio, with ocrelizumab demonstrating efficacy in both relapsing-remitting (RR) and primary-progressive (PP) MS in phase III clinical trials. Depletion of CD52 expressing T- and B-cells and monocytes by alemtuzumab resulted in impressive and durable suppression of disease activity in RRMS patients. On the other hand, strategies targeting B-cell cytokines such as atacicept resulted in increased disease activity. As our understanding of the biology of B-cells in MS is increasing, new compounds that target B-cells continue to be developed which promise to further expand the armamentarium of MS therapies and allow for more individualized therapy for patients with this complex disease.

  16. Targeting Prostate Cancer Stem Cells with Alpha-Particle Therapy

    Science.gov (United States)

    Ceder, Jens; Elgqvist, Jörgen

    2017-01-01

    Modern molecular and radiopharmaceutical development has brought the promise of tumor-selective delivery of antibody–drug conjugates to tumor cells for the diagnosis and treatment of primary and disseminated tumor disease. The classical mode of discourse regarding targeted therapy has been that the antigen targeted must be highly and homogenously expressed in the tumor cell population, and at the same time exhibit low expression in healthy tissue. However, there is increasing evidence that the reason cancer patients are not cured by current protocols is that there exist subpopulations of cancer cells that are resistant to conventional therapy including radioresistance and that these cells express other target antigens than the bulk of the tumor cells. These types of cells are often referred to as cancer stem cells (CSCs). The CSCs are tumorigenic and have the ability to give rise to all types of cells found in a cancerous disease through the processes of self-renewal and differentiation. If the CSCs are not eradicated, the cancer is likely to recur after therapy. Due to some of the characteristics of alpha particles, such as short path length and high density of energy depositions per distance traveled in tissue, they are especially well suited for use in targeted therapies against microscopic cancerous disease. The characteristics of alpha particles further make it possible to minimize the irradiation of non-targeted surrounding healthy tissue, but most importantly, make it possible to deliver high-absorbed doses locally and therefore eradicating small tumor cell clusters on the submillimeter level, or even single tumor cells. When alpha particles pass through a cell, they cause severe damage to the cell membrane, cytoplasm, and nucleus, including double-strand breaks of DNA that are very difficult to repair for the cell. This means that very few hits to a cell by alpha particles are needed in order to cause cell death, enabling killing of cells, such as CSCs

  17. Targeting Breast Cancer Cells for Destruction

    Science.gov (United States)

    2006-07-01

    specificity for some homeodomains in correlation with base pair 4 of the binding site, especially when the residue is phenylalanine or arginine (13, 14...Lysyl Hydroxylase (PLOD) Gene Expres- sion: Implications for the Pathology of Rieger Syndrome, J. Cell Biol. 152, 545-552. 29. Espinoza, H. M., Cox, C...requirement for phenylalanine in position 20 is well demonstrated by its conservation across the homeodomain family and its presence in the conserved

  18. Targeted Ablation of CML Stem Cells

    Science.gov (United States)

    2007-01-01

    the major active component in Feverfew (Tanacetum parthenium), an herbal medicine that has been used to treat migraine and rheumatoid arthritis for...glycerol for 15 minutes at room temperature. Protein/DNA complexes were resolved on a native polyacrylamide gel in 0.25 Tris-borate-EDTA (TBE...DNA complexes were resolved on a native polyacrylamide gel in 0.25X TBE. For immunoblots, cells were prepared and analyzed as previously described

  19. The mechanism of gene targeting in human somatic cells.

    Directory of Open Access Journals (Sweden)

    Yinan Kan

    2014-04-01

    Full Text Available Gene targeting in human somatic cells is of importance because it can be used to either delineate the loss-of-function phenotype of a gene or correct a mutated gene back to wild-type. Both of these outcomes require a form of DNA double-strand break (DSB repair known as homologous recombination (HR. The mechanism of HR leading to gene targeting, however, is not well understood in human cells. Here, we demonstrate that a two-end, ends-out HR intermediate is valid for human gene targeting. Furthermore, the resolution step of this intermediate occurs via the classic DSB repair model of HR while synthesis-dependent strand annealing and Holliday Junction dissolution are, at best, minor pathways. Moreover, and in contrast to other systems, the positions of Holliday Junction resolution are evenly distributed along the homology arms of the targeting vector. Most unexpectedly, we demonstrate that when a meganuclease is used to introduce a chromosomal DSB to augment gene targeting, the mechanism of gene targeting is inverted to an ends-in process. Finally, we demonstrate that the anti-recombination activity of mismatch repair is a significant impediment to gene targeting. These observations significantly advance our understanding of HR and gene targeting in human cells.

  20. The mechanism of gene targeting in human somatic cells.

    Science.gov (United States)

    Kan, Yinan; Ruis, Brian; Lin, Sherry; Hendrickson, Eric A

    2014-04-01

    Gene targeting in human somatic cells is of importance because it can be used to either delineate the loss-of-function phenotype of a gene or correct a mutated gene back to wild-type. Both of these outcomes require a form of DNA double-strand break (DSB) repair known as homologous recombination (HR). The mechanism of HR leading to gene targeting, however, is not well understood in human cells. Here, we demonstrate that a two-end, ends-out HR intermediate is valid for human gene targeting. Furthermore, the resolution step of this intermediate occurs via the classic DSB repair model of HR while synthesis-dependent strand annealing and Holliday Junction dissolution are, at best, minor pathways. Moreover, and in contrast to other systems, the positions of Holliday Junction resolution are evenly distributed along the homology arms of the targeting vector. Most unexpectedly, we demonstrate that when a meganuclease is used to introduce a chromosomal DSB to augment gene targeting, the mechanism of gene targeting is inverted to an ends-in process. Finally, we demonstrate that the anti-recombination activity of mismatch repair is a significant impediment to gene targeting. These observations significantly advance our understanding of HR and gene targeting in human cells.

  1. Nanomaterials in Targeting Cancer Stem Cells for Cancer Therapy

    Science.gov (United States)

    Qin, Weiwei; Huang, Guan; Chen, Zuanguang; Zhang, Yuanqing

    2017-01-01

    Cancer stem cells (CSCs) have been identified in almost all cancers and give rise to metastases and can also act as a reservoir of cancer cells that may cause a relapse after surgery, radiation, or chemotherapy. Thus they are obvious targets in therapeutic approaches and also a great challenge in cancer treatment. The threat presented by CSCs lies in their unlimited proliferative ability and multidrug resistance. These findings have necessitated an effective novel strategy to target CSCs for cancer treatment. Nanomaterials are on the route to providing novel methods in cancer therapies. Although, there have been a large number of excellent work in the field of targeted cancer therapy, it remains an open question how nanomaterials can meet future demands for targeting and eradicating of CSCs. In this review, we summarized recent and highlighted future prospects for targeting CSCs for cancer therapies by using a variety of nanomaterials.

  2. B cells as a target of immune modulation

    Directory of Open Access Journals (Sweden)

    Hawker Kathleen

    2009-01-01

    Full Text Available B cells have recently been identified as an integral component of the immune system; they play a part in autoimmunity through antigen presentation, antibody secretion, and complement activation. Animal models of multiple sclerosis (MS suggest that myelin destruction is partly mediated through B cell activation (and plasmablasts. MS patients with evidence of B cell involvement, as compared to those without, tend to have a worse prognosis. Finally, the significant decrease in new gadolinium-enhancing lesions, new T2 lesions, and relapses in MS patients treated with rituximab (a monoclonal antibody against CD20 on B cells leads us to the conclusion that B cells play an important role in MS and that immune modulation of these cells may ameliorate the disease. This article will explore the role of B cells in MS and the rationale for the development of B cell-targeted therapeutics. MS is an immune-mediated disease that affects over 2 million people worldwide and is the number one cause of disability in young patients. Most therapeutic targets have focused on T cells; however, recently, the focus has shifted to the role of B cells in the pathogenesis of MS and the potential of B cells as a therapeutic target.

  3. Improved drug targeting of cancer cells by utilizing actively targetable folic acid-conjugated albumin nanospheres.

    Science.gov (United States)

    Shen, Zheyu; Li, Yan; Kohama, Kazuhiro; Oneill, Brian; Bi, Jingxiu

    2011-01-01

    Folic acid-conjugated albumin nanospheres (FA-AN) have been developed to provide an actively targetable drug delivery system for improved drug targeting of cancer cells with reduced side effects. The nanospheres were prepared by conjugating folic acid onto the surface of albumin nanospheres using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) as a catalyst. To test the efficacy of these nanospheres as a potential delivery platform, doxorubicin-loaded albumin nanospheres (DOX-AN) and doxorubicin-loaded FA-AN (FA-DOX-AN) were prepared by entrapping DOX (an anthracycline, antibiotic drug widely used in cancer chemotherapy that works by intercalating DNA) into AN and FA-AN nanoparticles. Cell uptake of the DOX was then measured. The results show that FA-AN was incorporated into HeLa cells (tumor cells) only after 2.0h incubation, whereas HeLa cells failed to incorporate albumin nanospheres without conjugated folic acid after 4.0h incubation. When HeLa cells were treated with the DOX-AN, FA-DOX-AN nanoparticles or free DOX, cell viability decreased with increasing culture time (i.e. cell death increases with time) over a 70h period. Cell viability was always the lowest for free DOX followed by FA-DOX-AN4 and then DOX-AN. In a second set of experiments, HeLa cells washed to remove excess DOX after an initial incubation for 2h were incubated for 70h. The corresponding cell viability was slightly higher when the cells were treated with FA-DOX-AN or free DOX whilst cells treated with DOX-AN nanoparticles remained viable. The above experiments were repeated for non-cancerous, aortic smooth muscle cells (AoSMC). As expected, cell viability of the HeLa cells (with FA receptor alpha, FRα) and AoSMC cells (without FRα) decreased rapidly with time in the presence of free DOX, but treatment with FA-DOX-AN resulted in selective killing of the tumor cells. These results indicated that FA-AN may be used as a promising actively targetable drug delivery system to improve drug

  4. Targeting population heterogeneity for optimal cell factories

    DEFF Research Database (Denmark)

    Heins, Anna-Lena; Carlqvist, Magnus; Helmark, S.

    analysis, and thereby created the possibility to map population heterogeneity. A factorial design with pH, glucose concentration and oxygen level was performed in batch cultivations using the growth reporter strains to evaluate the effect of those environmental factors on heterogeneity level and amount...... of living cells. A highly dynamic behavior with regard to subpopulation distribution during the different growth stages was seen for the batch cultivations. Moreover, it could be demonstrated that the glucose concentration had a clear influence on the heterogeneity. The results from the factorial design...

  5. Targeting Strategies for Renal Cell Carcinoma: From Renal Cancer Cells to Renal Cancer Stem Cells

    OpenAIRE

    Zhi-xiang Yuan; Jingxin Mo; Guixian Zhao; Gang Shu; Hua-lin Fu; Wei Zhao

    2016-01-01

    Renal cell carcinoma (RCC) is a common form of urologic tumor that originates from the highly heterogeneous epithelium of renal tubules. Over the last decade, targeting therapies to renal cancer cells have transformed clinical care for RCC. Recently, it was proposed that renal cancer stem cells (CSCs) isolated from renal carcinomas were responsible for driving tumor growth and resistance to conventional chemotherapy and radiotherapy, according to the theory of CSCs; this has provided the rati...

  6. Novel cAMP targets in cell proliferation

    NARCIS (Netherlands)

    Kuiperij, Hinke Bertha

    2004-01-01

    cAMP is a second messenger that plays a role in a wide variety of biological processes, one of which is the regulation of cell proliferation. Adenylate cyclases generate cAMP in the cell upon activation, followed by binding to and activation of its direct targets, PKA and Epac. PKA is a protein kina

  7. Glypican-3 Targeting of Liver Cancer Cells Using Multifunctional Nanoparticles

    Directory of Open Access Journals (Sweden)

    James O. Park

    2011-01-01

    Full Text Available Imaging is essential in accurately detecting, staging, and treating primary liver cancer (hepatocellular carcinoma [HCC], one of the most prevalent and lethal malignancies. We developed a novel multifunctional nanoparticle (NP specifically targeting glypican-3 (GPC3, a proteoglycan implicated in promotion of cell growth that is overexpressed in most HCCs. Quantitative real-time polymerase chain reaction was performed to confirm the differential GPC3 expression in two human HCC cells, Hep G2 (high and HLF (negligible. These cells were treated with biotin-conjugated GPC3 monoclonal antibody (αGPC3 and subsequently targeted using superparamagnetic iron oxide NPs conjugated to streptavidin and Alexa Fluor 647. Flow cytometry demonstrated that only GPC3-expressing Hep G2 cells were specifically targeted using this αGPC3-NP conjugate (fourfold mean fluorescence over nontargeted NP, and magnetic resonance imaging (MRI experiments showed similar findings (threefold R2 relaxivity. Confocal fluorescence microscopy localized the αGPC3 NPs only to the cell surface of GPC3-expressing Hep G2 cells. Further characterization of this construct demonstrated a negatively charged, monodisperse, 50 nm NP, ideally suited for tumor targeting. This GPC3-specific NP system, with dual-modality imaging capability, may enhance pretreatment MRI, enable refined intraoperative HCC visualization by near-infrared fluorescence, and be potentially used as a carrier for delivery of tumor-targeted therapies, improving patient outcomes.

  8. The quest for targets executing MYC-dependent cell transformation

    Directory of Open Access Journals (Sweden)

    Markus eHartl

    2016-06-01

    Full Text Available MYC represents a transcription factor with oncogenic potential converting multiple cellular signals into a broad transcriptional response, thereby controlling the expression of numerous protein-coding and non-coding RNAs important for cell proliferation, metabolism, differentiation, and apoptosis. Constitutive activation of MYC leads to neoplastic cell transformation, and deregulated MYC alleles are frequently observed in many human cancer cell types. Multiple approaches have been performed to isolate genes differentially expressed in cells containing aberrantly activated MYC proteins leading to the identification of thousands of putative targets. Functional analyses of genes differentially expressed in MYC-transformed cells had revealed that so far more than forty upregulated or downregulated MYC targets are actively involved in cell transformation or tumorigenesis. However, for determination which of the known, or yet unidentified targets are responsible for processing the oncogenic MYC program, further systematic and selective approaches are required. The search for critical targets in MYC-dependent tumor cells is exacerbated by the fact that during tumor development, cancer cells progressively evolve in a multistep process thereby acquiring their characteristic features in an additive manner. Functional expression cloning, combinatorial gene expression and appropriate in vivo tests could represent adequate tools for dissecting the complex scenario of MYC-specified cell transformation. In this context, the central goal is to identify a minimal set of targets that suffices to phenocopy oncogenic MYC. Recently developed genomic editing tools could be employed to confirm the requirement of crucial transformation-associated targets.Knowledge about essential MYC regulated genes is beneficial to expedite the development of specific inhibitors to interfere with growth and viability of human tumor cells in which MYC is aberrantly activated

  9. Targeting dendritic cells in vivo for cancer therapy

    Directory of Open Access Journals (Sweden)

    Irina eCaminschi

    2012-02-01

    Full Text Available Monoclonal antibodies that recognise cell surface molecules have been used deliver antigenic cargo to dendritic cells (DC for induction of immune responses. The encouraging anti-tumour immunity elicited using this immunisation strategy suggests its suitability for clinical trials. This review discusses the complex network of DC, the functional specialisation of DC-subsets, the immunological outcomes of targeting different DC-subsets and their cell surface receptors, and the requirements for the induction of effective anti-tumour immunity. Finally, we review preclinical experiments and the progress towards targeting human DC in vivo.

  10. Mitochondria as therapeutic targets for cancer stem cells

    Institute of Scientific and Technical Information of China (English)

    In Sung Song; Jeong Yu Jeong; Seung Hun Jeong; Hyoung Kyu Kim; Kyung Soo Ko; Byoung Doo Rhee; Nari Kim; Jin Han

    2015-01-01

    Cancer stem cells (CSCs) are maintained by theirsomatic stem cells and are responsible for tumorinitiation, chemoresistance, and metastasis. Evidencefor the CSCs existence has been reported for a numberof human cancers. The CSC mitochondria have beenshown recently to be an important target for cancertreatment, but clinical significance of CSCs and theirmitochondria properties remain unclear. Mitochondriatargetedagents are considerably more effectivecompared to other agents in triggering apoptosis ofCSCs, as well as general cancer cells, via mitochondrialdysfunction. Mitochondrial metabolism is altered incancer cells because of their reliance on glycolyticintermediates, which are normally destined for oxidativephosphorylation. Therefore, inhibiting cancer-specificmodifications in mitochondrial metabolism, increasingreactive oxygen species production, or stimulatingmitochondrial permeabilization transition could bepromising new therapeutic strategies to activate celldeath in CSCs as well, as in general cancer cells. Thisreview analyzed mitochondrial function and its potentialas a therapeutic target to induce cell death in CSCs.Furthermore, combined treatment with mitochondriatargeteddrugs will be a promising strategy for thetreatment of relapsed and refractory cancer.

  11. Immunologic targeting of FOXP3 in inflammatory breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Smita Nair

    Full Text Available The forkhead transcription factor FOXP3 is necessary for induction of regulatory T lymphocytes (Tregs and their immunosuppressive function. We have previously demonstrated that targeting Tregs by vaccination of mice with murine FOXP3 mRNA-transfected dendritic cells (DCs elicits FOXP3-specific T cell responses and enhances tumor immunity. It is clear that FOXP3 expression is not restricted to T-cell lineage and herein, using RT-PCR, flow cytometry, and western immunoblot we demonstrate for the first time that FOXP3 is expressed in inflammatory breast cancer (IBC cells, SUM149 (triple negative, ErbB1-activated and SUM190 (ErbB2-overexpressing. Importantly, FOXP3-specific T cells generated in vitro using human FOXP3 RNA-transfected DCs as stimulators efficiently lyse SUM149 cells. Interestingly, an isogenic model (rSUM149 derived from SUM149 with an enhanced anti-apoptotic phenotype was resistant to FOXP3-specific T cell mediated lysis. The MHC class I cellular processing mechanism was intact in both cell lines at the protein and transcription levels suggesting that the resistance to cytolysis by rSUM149 cells was not related to MHC class I expression or to the MHC class I antigen processing machinery in these cells. Our data suggest that FOXP3 may be an effective tumor target in IBC cells however increased anti-apoptotic signaling can lead to immune evasion.

  12. Targeted cancer cell death induced by biofunctionalized magnetic nanowires

    KAUST Repository

    Contreras, Maria F.

    2014-02-01

    Magnetic micro and nanomaterials are increasingly interesting for biomedical applications since they possess many advantageous properties: they can become biocompatible, they can be functionalized to target specific cells and they can be remotely manipulated by magnetic fields. The goal of this study is to use antibody-functionalized nickel nanowires (Ab-NWs) as an alternative method in cancer therapy overcoming the limitations of current treatments that lack specificity and are highly cytotoxic. Ab-NWs have been incubated with cancer cells and a 12% drop on cell viability was observed for a treatment of only 10 minutes and an alternating magnetic field of low intensity and low frequency. It is believed that the Ab-NWs vibrate transmitting a mechanical force to the targeted cells inducing cell death. © 2014 IEEE.

  13. The cell growth suppressor, mir-126, targets IRS-1.

    Science.gov (United States)

    Zhang, Jin; Du, Ying-ying; Lin, Yi-feng; Chen, Ya-ting; Yang, Lu; Wang, Hui-jun; Ma, Duan

    2008-12-05

    miRNAs are a family of approximately 22-nuleotide-long noncoding RNAs involved in the formation and progress of tumors. Since traditional methods for the detection of miRNAs expression have many disadvantages, we developed a simple method called polyA RT PCR. With this method, we detected a series of miRNAs and found that mir-126 is one of the miRNAs underexpressed in breast cancer cells. Flow cytometry analysis showed that mir-126 inhibited cell cycle progression from G1/G0 to S. Further studies revealed that mir-126 targeted IRS-1 at the translation level. Knocking down of IRS-1 suppresses cell growth in HEK293 and breast cancer cell MCF-7, which recapitulates the effects of mir-126. In conclusion, we developed a simple method for high-throughput screening of miRNAs and found that mir-126, a cell growth suppressor, targets IRS-1.

  14. PEG-templated mesoporous silica nanoparticles exclusively target cancer cells

    Science.gov (United States)

    Morelli, Catia; Maris, Pamela; Sisci, Diego; Perrotta, Enrico; Brunelli, Elvira; Perrotta, Ida; Panno, Maria Luisa; Tagarelli, Antonio; Versace, Carlo; Casula, Maria Francesca; Testa, Flaviano; Andò, Sebastiano; Nagy, Janos B.; Pasqua, Luigi

    2011-08-01

    Mesoporous silica nanoparticles (MSNs) have been proposed as DNA and drug delivery carriers, as well as efficient tools for fluorescent cell tracking. The major limitation is that MSNs enter cells regardless of a target-specific functionalization. Here we show that non functionalized MSNs, synthesized using a PEG surfactant-based interfacial synthesis procedure, do not enter cells, while a highly specific, receptor mediated, cellular internalization of folic acid (FOL) grafted MSNs (MSN-FOL), occurs exclusively in folate receptor (FR) expressing cells. Neither the classical clathrin pathway nor macropinocytosis is involved in the MSN endocytic process, while fluorescent MSNs (MSN-FITC) enter cells through aspecific, caveolae-mediated, endocytosis. Moreover, internalized particles seem to be mostly exocytosed from cells within 96 h. Finally, cisplatin (Cp) loaded MSN-FOL were tested on cancerous FR-positive (HeLa) or normal FR-negative (HEK293) cells. A strong growth arrest was observed only in HeLa cells treated with MSN-FOL-Cp. The results presented here show that our mesoporous nanoparticles do not enter cells unless opportunely functionalized, suggesting that they could represent a promising vehicle for drug targeting applications.Mesoporous silica nanoparticles (MSNs) have been proposed as DNA and drug delivery carriers, as well as efficient tools for fluorescent cell tracking. The major limitation is that MSNs enter cells regardless of a target-specific functionalization. Here we show that non functionalized MSNs, synthesized using a PEG surfactant-based interfacial synthesis procedure, do not enter cells, while a highly specific, receptor mediated, cellular internalization of folic acid (FOL) grafted MSNs (MSN-FOL), occurs exclusively in folate receptor (FR) expressing cells. Neither the classical clathrin pathway nor macropinocytosis is involved in the MSN endocytic process, while fluorescent MSNs (MSN-FITC) enter cells through aspecific, caveolae

  15. High efficiency cell-specific targeting of cytokine activity

    Science.gov (United States)

    Garcin, Geneviève; Paul, Franciane; Staufenbiel, Markus; Bordat, Yann; van der Heyden, José; Wilmes, Stephan; Cartron, Guillaume; Apparailly, Florence; de Koker, Stefaan; Piehler, Jacob; Tavernier, Jan; Uzé, Gilles

    2014-01-01

    Systemic toxicity currently prevents exploiting the huge potential of many cytokines for medical applications. Here we present a novel strategy to engineer immunocytokines with very high targeting efficacies. The method lies in the use of mutants of toxic cytokines that markedly reduce their receptor-binding affinities, and that are thus rendered essentially inactive. Upon fusion to nanobodies specifically binding to marker proteins, activity of these cytokines is selectively restored for cell populations expressing this marker. This ‘activity-by-targeting’ concept was validated for type I interferons and leptin. In the case of interferon, activity can be directed to target cells in vitro and to selected cell populations in mice, with up to 1,000-fold increased specific activity. This targeting strategy holds promise to revitalize the clinical potential of many cytokines.

  16. Stem cell guidance through the mechanistic target of rapamycin

    Institute of Scientific and Technical Information of China (English)

    Kenneth; Maiese

    2015-01-01

    Stem cells offer great promise for the treatment of multiple disorders throughout the body. Critical to this premise is the ability to govern stem cell pluripotency, proliferation, and differentiation. The mechanistic target of rapamycin(mT OR), 289-kD a serine/threonine protein kinase, that is a vital component of mT OR Complex 1 and mT OR Complex 2 represents a critical pathway for the oversight of stem cell maintenance. mT OR can control the programmed cell death pathways of autophagy andapoptosis that can yield variable outcomes in stem cell survival and be reliant upon proliferative pathways that include Wnt signaling, Wnt1 inducible signaling pathway protein 1(WISP1), silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1), and trophic factors. mT OR also is a necessary component for the early development and establishment of stem cells as well as having a significant impact in the regulation of the maturation of specific cell phenotypes. Yet, as a proliferative agent, mT OR can not only foster cancer stem cell development and tumorigenesis, but also mediate cell senescence under certain conditions to limit invasive cancer growth. mT OR offers an exciting target for the oversight of stem cell therapies but requires careful consideration of the diverse clinical outcomes that can be fueled by mT OR signaling pathways.

  17. Salinomycin inhibits osteosarcoma by targeting its tumor stem cells.

    Science.gov (United States)

    Tang, Qing-Lian; Zhao, Zhi-Qiang; Li, Jin-Chun; Liang, Yi; Yin, Jun-Qiang; Zou, Chang-Ye; Xie, Xian-Biao; Zeng, Yi-Xin; Shen, Jing-Nan; Kang, Tiebang; Wang, Jin

    2011-12-01

    Osteosarcoma is the most common primary bone tumor in children and adolescents and is typically associated with a poor prognosis. Tumor stem cells (TSCs) are presumed to drive tumor initiation and tumor relapse or metastasis. Hence, the poor prognosis of osteosarcoma likely results from a failure to target the osteosarcoma stem cells. Here, we have utilized three different methods to enrich TSCs in osteosarcoma and further evaluated whether salinomycin could selectively target TSCs in osteosarcoma. Our results indicated that sarcosphere selection, chemotherapy selection and stem cell marker OCT4 or SOX2 over-expression are all effective in the enrichment of TSCs from osteosarcoma cell lines. Further investigation found that salinomycin inhibited osteosarcoma by selectively targeting its stem cells both in vitro and in vivo without severe side effects, and the Wnt/β-catenin signaling pathway may be involved in this inhibition of salinomycin. Taken together, we have identified that salinomycin is an effective inhibitor of osteosarcoma stem cells, supporting the use of salinomycin for elimination of osteosarcoma stem cells and implying a need for further clinical evaluation.

  18. Dendritic cell targeted vaccines: Recent progresses and challenges.

    Science.gov (United States)

    Chen, Pengfei; Liu, Xinsheng; Sun, Yuefeng; Zhou, Peng; Wang, Yonglu; Zhang, Yongguang

    2016-03-01

    Dendritic cells (DCs) are known to be a set of morphology, structure and function of heterogeneous professional antigen presenting cells (APCs), as well as the strongest functional antigen presenting cells, which can absorb, process and present antigens. As the key regulators of innate and adaptive immune responses, DCs are at the center of the immune system and capable of interacting with both B cells and T cells, thereby manipulating the humoral and cellular immune responses. DCs provide an essential link between the innate and adaptive immunity, and the strong immune activation function of DCs and their properties of natural adjuvants, make them a valuable target for antigen delivery. Targeting antigens to DC-specific endocytic receptors in combination with the relevant antibodies or ligands along with immunostimulatory adjuvants has been recently recognized as a promising strategy for designing an effective vaccine that elicits a strong and durable T cell response against intracellular pathogens and cancer. This opinion article provides a brief summary of the rationales, superiorities and challenges of existing DC-targeting approaches.

  19. Calcium-mediated oxidative stress: a common mechanism in tight junction disruption by different types of cellular stress.

    Science.gov (United States)

    Gangwar, Ruchika; Meena, Avtar S; Shukla, Pradeep K; Nagaraja, Archana S; Dorniak, Piotr L; Pallikuth, Sandeep; Waters, Christopher M; Sood, Anil; Rao, RadhaKrishna

    2017-02-20

    The role of reactive oxygen species (ROS) in osmotic stress, dextran sulfate sodium (DSS) and cyclic stretch-induced tight junction (TJ) disruption was investigated in Caco-2 cell monolayers in vitro and restraint stress-induced barrier dysfunction in mouse colon in vivo Live cell imaging showed that osmotic stress, cyclic stretch and DSS triggered rapid production of ROS in Caco-2 cell monolayers, which was blocked by depletion of intracellular Ca(2+) by 1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid. Knockdown of CaV1.3 or TRPV6 channels blocked osmotic stress and DSS-induced ROS production and attenuated TJ disruption and barrier dysfunction. N-Acetyl l-cysteine (NAC) and l-N(G)-Nitroarginine methyl ester (l-NAME) blocked stress-induced TJ disruption and barrier dysfunction. NAC and l-NAME also blocked stress-induced activation of c-Jun N-terminal kinase (JNK) and c-Src. ROS was colocalized with the mitochondrial marker in stressed cells. Cyclosporin A blocked osmotic stress and DSS-induced ROS production, barrier dysfunction, TJ disruption and JNK activation. Mitochondria-targeted Mito-TEMPO blocked osmotic stress and DSS-induced barrier dysfunction and TJ disruption. Chronic restraint stress in mice resulted in the elevation of intracellular Ca(2+), activation of JNK and c-Src, and disruption of TJ in the colonic epithelium. Furthermore, corticosterone administration induced JNK and c-Src activation, TJ disruption and protein thiol oxidation in colonic mucosa. The present study demonstrates that oxidative stress is a common signal in the mechanism of TJ disruption in the intestinal epithelium by different types of cellular stress in vitro and bio behavioral stress in vivo.

  20. Multimodal imaging of nanovaccine carriers targeted to human dendritic cells

    NARCIS (Netherlands)

    Cruz, L.J.; Tacken, P.J.; Bonetto, F.J.; Buschow, S.I.; Croes, H.J.E.; Wijers-Rouw, M.J.P.; Vries, I.J.M. de; Figdor, C.G.

    2011-01-01

    Dendritic cells (DCs) are key players in the initiation of adaptive immune responses and are currently exploited in immunotherapy against cancer and infectious diseases. The targeted delivery of nanovaccine particles (NPs) to DCs in vivo is a promising strategy to enhance immune responses. Here, tar

  1. Targeted genome editing in human repopulating haematopoietic stem cells

    NARCIS (Netherlands)

    P. Genovese (Pietro); G. Schiroli (Giulia); G. Escobar (Giulia); T. Di Tomaso (Tiziano); C. Firrito (Claudia); A. Calabria (Andrea); D. Moi (Davide); R. Mazzieri (Roberta); C. Bonini (Chiara); M.V. Holmes (Michael); P.D. Gregory (Philip); M. van der Burg (Mirjam); B. Gentner (Bernhard); E. Montini (Eugenio); A. Lombardo (Angelo); L. Naldini (Luigi)

    2014-01-01

    textabstractTargeted genome editing by artificial nucleases has brought the goal of site-specific transgene integration and gene correction within the reach of gene therapy. However, its application to long-term repopulating haematopoietic stem cells (HSCs) has remained elusive. Here we show that po

  2. Cell-penetrating antimicrobial peptides - prospectives for targeting intracellular infections

    DEFF Research Database (Denmark)

    Bahnsen, Jesper S; Franzyk, Henrik; Sayers, Edward J;

    2015-01-01

    . TPk showed the highest antibacterial activity. SA-3 exhibited selective disruption of liposomes mimicking Gram-positive and Gram-negative membranes. CONCLUSION: PK-12-KKP is an unlikely candidate for targeting intracellular bacteria, as the eukaryotic cell-penetrating ability is poor. SA-3, affected...

  3. Human skin Langerhans cells are targets of dengue virus infection

    NARCIS (Netherlands)

    Wu, SJL; Grouard-Vogel, G; Mascola, [No Value; Brachtel, E; Putvatana, R; Louder, MK; Filgueira, L; Marovich, MA; Wong, HK; Blauvelt, A; Murphy, GS; Robb, ML; Innes, BL; Birx, DL; Hayes, CG; Frankel, SS

    2000-01-01

    Dengue virus (DV), an arthropod-borne flavivirus, causes a febrile illness for which there is no antiviral treatment and no vaccine(1,2). Macrophages are important in dengue pathogenesis; however, the initial target cell for DV infection remains unknown. As DV is introduced into human skin by mosqui

  4. Polylactic Acid Nanoparticles Targeted to Brain Microvascular Endothelial Cells

    Institute of Scientific and Technical Information of China (English)

    WANG Huafang; HU Yu; SUN Wangqiang; XIE Changsheng

    2005-01-01

    In this work, blank polylactic acid (PLA) nanoparticles with unstained surface were prepared by the nano-deposition method. On the basis of the preparation, the effect of surface modification on brain microvascular endothelial cells (BMECs) targeting was examined by in vivo experiments and fluorescence microscopy. The results showed that PLA nanoparticles are less toxic than PACA nanoparticles but their BMECs targeting is similar to PACA nanoparticles. The experiments suggest that drugs can be loaded onto the particles and become more stable through adsorption on the surface of PLA nanoparticles with high surface activity. The surface of PLA nanoparticles was obviously modified and the hydrophilicity was increased as well in the presence of non-ionic surfactants on PLA nanoparticles. As a targeting moiety, polysobate 80 (T-80) can facilitate BMECs targeting of PLA nanoparticles.

  5. Multiple personalities: synaptic target cells as introverts and extroverts.

    Science.gov (United States)

    Ritzenthaler, S; Chiba, A

    2001-10-01

    The intricate process of wiring a neuronetwork requires a high degree of accuracy in the communication between pre- and post-synaptic cells. While presynaptic cells have been widely recognized for their dynamic role in synaptic matchmaking, post-synaptic cells have historically been overlooked as passive targets. Recent studies in the Drosophila embryonic neuromuscular system provide compelling evidence that post-synaptic cells participate actively in the synaptogenic process. Endocytosis allows them to quickly modify the array of molecular cues they provide on their surfaces and the extension of dynamic filopodia allows post-synaptic cells to engage in direct long-distance communication. By making use of familiar cellular mechanisms such as endocytosis and filopodia formation, post-synaptic cells may be able to communicate more effectively with potential synaptic partners.

  6. Oncotripsy: Targeting cancer cells selectively via resonant harmonic excitation

    CERN Document Server

    Heyden, Stefanie

    2015-01-01

    We investigate a method of selectively targeting cancer cells by means of ultrasound harmonic excitation at their resonance frequency, which we refer to as oncotripsy. The geometric model of the cells takes into account the cytoplasm, nucleus and nucleolus, as well as the plasma membrane and nuclear envelope. Material properties are varied within a pathophysiologically-relevant range. A first modal analysis reveals the existence of a spectral gap between the natural frequencies and, most importantly, resonant growth rates of healthy and cancerous cells. The results of the modal analysis are verified by simulating the fully-nonlinear transient response of healthy and cancerous cells at resonance. The fully nonlinear analysis confirms that cancerous cells can be selectively taken to lysis by the application of carefully tuned ultrasound harmonic excitation while simultaneously leaving healthy cells intact.

  7. Oncotripsy: Targeting cancer cells selectively via resonant harmonic excitation

    Science.gov (United States)

    Heyden, S.; Ortiz, M.

    2016-07-01

    We investigate a method of selectively targeting cancer cells by means of ultrasound harmonic excitation at their resonance frequency, which we refer to as oncotripsy. The geometric model of the cells takes into account the cytoplasm, nucleus and nucleolus, as well as the plasma membrane and nuclear envelope. Material properties are varied within a pathophysiologically-relevant range. A first modal analysis reveals the existence of a spectral gap between the natural frequencies and, most importantly, resonant growth rates of healthy and cancerous cells. The results of the modal analysis are verified by simulating the fully-nonlinear transient response of healthy and cancerous cells at resonance. The fully nonlinear analysis confirms that cancerous cells can be selectively taken to lysis by the application of carefully tuned ultrasound harmonic excitation while simultaneously leaving healthy cells intact.

  8. Breast cancer stem cells, EMT and therapeutic targets

    Energy Technology Data Exchange (ETDEWEB)

    Kotiyal, Srishti; Bhattacharya, Susinjan, E-mail: s.bhattacharya@jiit.ac.in

    2014-10-10

    Highlights: • Therapeutic targeting or inhibition of the key molecules of signaling pathways can control growth of breast cancer stem cells (BCSCs). • Development of BCSCs also involves miRNA interactions. • Therapeutic achievement can be done by targeting identified targets in the BCSC pathways. - Abstract: A small heterogeneous population of breast cancer cells acts as seeds to induce new tumor growth. These seeds or breast cancer stem cells (BCSCs) exhibit great phenotypical plasticity which allows them to undergo “epithelial to mesenchymal transition” (EMT) at the site of primary tumor and a future reverse transition. Apart from metastasis they are also responsible for maintaining the tumor and conferring it with drug and radiation resistance and a tendency for post-treatment relapse. Many of the signaling pathways involved in induction of EMT are involved in CSC generation and regulation. Here we are briefly reviewing the mechanism of TGF-β, Wnt, Notch, TNF-α, NF-κB, RTK signalling pathways which are involved in EMT as well as BCSCs maintenance. Therapeutic targeting or inhibition of the key/accessory players of these pathways could control growth of BCSCs and hence malignant cancer. Additionally several miRNAs are dysregulated in cancer stem cells indicating their roles as oncogenes or tumor suppressors. This review also lists the miRNA interactions identified in BCSCs and discusses on some newly identified targets in the BCSC regulatory pathways like SHIP2, nicastrin, Pin 1, IGF-1R, pro-inflammatory cytokines and syndecan which can be targeted for therapeutic achievements.

  9. NK Cells Preferentially Target Tumor Cells with a Cancer Stem Cell Phenotype.

    Science.gov (United States)

    Ames, Erik; Canter, Robert J; Grossenbacher, Steven K; Mac, Stephanie; Chen, Mingyi; Smith, Rachel C; Hagino, Takeshi; Perez-Cunningham, Jessica; Sckisel, Gail D; Urayama, Shiro; Monjazeb, Arta M; Fragoso, Ruben C; Sayers, Thomas J; Murphy, William J

    2015-10-15

    Increasing evidence supports the hypothesis that cancer stem cells (CSCs) are resistant to antiproliferative therapies, able to repopulate tumor bulk, and seed metastasis. NK cells are able to target stem cells as shown by their ability to reject allogeneic hematopoietic stem cells but not solid tissue grafts. Using multiple preclinical models, including NK coculture (autologous and allogeneic) with multiple human cancer cell lines and dissociated primary cancer specimens and NK transfer in NSG mice harboring orthotopic pancreatic cancer xenografts, we assessed CSC viability, CSC frequency, expression of death receptor ligands, and tumor burden. We demonstrate that activated NK cells are capable of preferentially killing CSCs identified by multiple CSC markers (CD24(+)/CD44(+), CD133(+), and aldehyde dehydrogenase(bright)) from a wide variety of human cancer cell lines in vitro and dissociated primary cancer specimens ex vivo. We observed comparable effector function of allogeneic and autologous NK cells. We also observed preferential upregulation of NK activation ligands MICA/B, Fas, and DR5 on CSCs. Blocking studies further implicated an NKG2D-dependent mechanism for NK killing of CSCs. Treatment of orthotopic human pancreatic cancer tumor-bearing NSG mice with activated NK cells led to significant reductions in both intratumoral CSCs and tumor burden. Taken together, these data from multiple preclinical models, including a strong reliance on primary human cancer specimens, provide compelling preclinical evidence that activated NK cells preferentially target cancer cells with a CSC phenotype, highlighting the translational potential of NK immunotherapy as part of a combined modality approach for refractory solid malignancies.

  10. Liposomes to target peripheral neurons and Schwann cells.

    Directory of Open Access Journals (Sweden)

    Sooyeon Lee

    Full Text Available While a wealth of literature for tissue-specific liposomes is emerging, optimal formulations to target the cells of the peripheral nervous system (PNS are lacking. In this study, we asked whether a novel formulation of phospholipid-based liposomes could be optimized for preferential uptake by microvascular endothelia, peripheral neurons and Schwann cells. Here, we report a unique formulation consisting of a phospholipid, a polymer surfactant and cholesterol that result in enhanced uptake by targeted cells. Using fluorescently labeled liposomes, we followed particle internalization and trafficking through a distinct route from dextran and escape from degradative compartments, such as lysosomes. In cultures of non-myelinating Schwann cells, liposomes associate with the lipid raft marker Cholera toxin, and their internalization is inhibited by disruption of lipid rafts or actin polymerization. In contrast, pharmacological inhibition of clathrin-mediated endocytosis does not significantly impact liposome entry. To evaluate the efficacy of liposome targeting in tissues, we utilized myelinating explant cultures of dorsal root ganglia and isolated diaphragm preparations, both of which contain peripheral neurons and myelinating Schwann cells. In these models, we detected preferential liposome uptake into neurons and glial cells in comparison to surrounding muscle tissue. Furthermore, in vivo liposome administration by intramuscular or intravenous injection confirmed that the particles were delivered to myelinated peripheral nerves. Within the CNS, we detected the liposomes in choroid epithelium, but not in myelinated white matter regions or in brain parenchyma. The described nanoparticles represent a novel neurophilic delivery vehicle for targeting small therapeutic compounds, biological molecules, or imaging reagents into peripheral neurons and Schwann cells, and provide a major advancement toward developing effective therapies for peripheral

  11. Novel therapeutic Strategies for Targeting Liver Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Naoki Oishi, Xin Wei Wang

    2011-01-01

    Full Text Available The cancer stem cell (CSC hypothesis was first proposed over 40 years ago. Advances in CSC isolation were first achieved in hematological malignancies, with the first CSC demonstrated in acute myeloid leukemia. However, using similar strategies and technologies, and taking advantage of available surface markers, CSCs have been more recently demonstrated in a growing range of epithelial and other solid organ malignancies, suggesting that the majority of malignancies are dependent on such a compartment.Primary liver cancer consists predominantly of hepatocellular carcinoma (HCC and intrahepatic cholangiocarcinoma (ICC. It is believed that hepatic progenitor cells (HPCs could be the origin of some HCCs and ICCs. Furthermore, stem cell activators such as Wnt/β-catenin, TGF-β, Notch and Hedgehog signaling pathways also expedite tumorigenesis, and these pathways could serve as molecular targets to assist in designing cancer prevention strategies. Recent studies indicate that additional factors such as EpCAM, Lin28 or miR-181 may also contribute to HCC progression by targeting HCC CSCs. Various therapeutic drugs that directly modulate CSCs have been examined in vivo and in vitro. However, CSCs clearly have a complex pathogenesis, with a considerable crosstalk and redundancy in signaling pathways, and hence targeting single molecules or pathways may have a limited benefit for treatment. Many of the key signaling molecules are shared by both CSCs and normal stem cells, which add further challenges for designing molecularly targeted strategies specific to CSCs but sparing normal stem cells to avoid side effects. In addition to the direct control of CSCs, many other factors that are needed for the maintenance of CSCs, such as angiogenesis, vasculogenesis, invasion and migration, hypoxia, immune evasion, multiple drug resistance, and radioresistance, should be taken into consideration when designing therapeutic strategies for HCC.Here we provide a brief

  12. Targeting cancer stem cells: emerging role of Nanog transcription factor

    Directory of Open Access Journals (Sweden)

    Wang ML

    2013-09-01

    Full Text Available Mong-Lien Wang,1 Shih-Hwa Chiou,2,3 Cheng-Wen Wu1,4–61Institute of Biochemistry and Molecular Biology, 2Institute of Pharmacology, National Yang Ming University, Taipei, Taiwan; 3Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan; 4Institute of Microbiology and Immunology, 5Institute of Clinical Medicine, National Yang Ming University, Taipei, Taiwan; 6Institute of Biomedical Science, Academia Sinica, Taipei, TaiwanAbstract: The involvement of stemness factors in cancer initiation and progression has drawn much attention recently, especially after the finding that introducing four stemness factors in somatic cells is able to reprogram the cells back to an embryonic stem cell-like state. Following accumulating data revealing abnormal elevated expression levels of key stemness factors, like Nanog, Oct4, and Sox2, in several types of cancer stem cells; the importance and therapeutic potential of targeting these stemness regulators in cancers has turned to research focus. Nanog determines cell fate in both embryonic and cancer stem cells; activating Nanog at an inappropriate time would result in cancer stem cells rather than normal pluripotent stem cells or differentiated somatic cells. Upregulated Nanog is correlated with poor survival outcome of patients with various types of cancer. The discoveries of downstream regulatory pathways directly or indirectly mediated by Nanog indicate that Nanog regulates several aspects of cancer development such as tumor cell proliferation, self-renewal, motility, epithelial-mesenchymal transition, immune evasion, and drug-resistance, which are all defined features for cancer stem cells. The current review paper illustrates the central role of Nanog in the regulatory networks of cancer malignant development and stemness acquirement, as well as in the communication between cancer cells and the surrounding stroma. Though a more defined model is needed to test the

  13. Lactoferrin targets T cells in the small intestine

    DEFF Research Database (Denmark)

    Nielsen, Sanne Mie; Hansen, Gert Helge; Danielsen, E Michael

    2010-01-01

    pathogens, and Lf receptors have been identified at the surfaces of a number of different cells. In the small intestine Lf binds to the luminal surface, but its further interaction with the epithelial cells is controversial. METHODS: In the present work, we studied the uptake of Lf in cultured mucosal...... explants of pig small intestine by immunofluorescence and immunogold microscopy. RESULTS: Lf rapidly bound to the brush border and subsequently appeared in punctae in the apical cytoplasm, indicating internalization into an endosomal compartment. Essentially, no labeling was detected elsewhere...... defense of the small intestinal mucosa by targeting the population of T cells in the lamina propria....

  14. Key cancer cell signal transduction pathways as therapeutic targets.

    Science.gov (United States)

    Bianco, Roberto; Melisi, Davide; Ciardiello, Fortunato; Tortora, Giampaolo

    2006-02-01

    Growth factor signals are propagated from the cell surface, through the action of transmembrane receptors, to intracellular effectors that control critical functions in human cancer cells, such as differentiation, growth, angiogenesis, and inhibition of cell death and apoptosis. Several kinases are involved in transduction pathways via sequential signalling activation. These kinases include transmembrane receptor kinases (e.g., epidermal growth factor receptor EGFR); or cytoplasmic kinases (e.g., PI3 kinase). In cancer cells, these signalling pathways are often altered and results in a phenotype characterized by uncontrolled growth and increased capability to invade surrounding tissue. Therefore, these crucial transduction molecules represent attractive targets for cancer therapy. This review will summarize current knowledge of key signal transduction pathways, that are altered in cancer cells, as therapeutic targets for novel selective inhibitors. The most advanced targeted agents currently under development interfere with function and expression of several signalling molecules, including the EGFR family; the vascular endothelial growth factor and its receptors; and cytoplasmic kinases such as Ras, PI3K and mTOR.

  15. Resistance to antibiotics targeted to the bacterial cell wall.

    Science.gov (United States)

    Nikolaidis, I; Favini-Stabile, S; Dessen, A

    2014-03-01

    Peptidoglycan is the main component of the bacterial cell wall. It is a complex, three-dimensional mesh that surrounds the entire cell and is composed of strands of alternating glycan units crosslinked by short peptides. Its biosynthetic machinery has been, for the past five decades, a preferred target for the discovery of antibacterials. Synthesis of the peptidoglycan occurs sequentially within three cellular compartments (cytoplasm, membrane, and periplasm), and inhibitors of proteins that catalyze each stage have been identified, although not all are applicable for clinical use. A number of these antimicrobials, however, have been rendered inactive by resistance mechanisms. The employment of structural biology techniques has been instrumental in the understanding of such processes, as well as the development of strategies to overcome them. This review provides an overview of resistance mechanisms developed toward antibiotics that target bacterial cell wall precursors and its biosynthetic machinery. Strategies toward the development of novel inhibitors that could overcome resistance are also discussed.

  16. Lysosomal disruption preferentially targets acute myeloid leukemia cells and progenitors

    Science.gov (United States)

    Sukhai, Mahadeo A.; Prabha, Swayam; Hurren, Rose; Rutledge, Angela C.; Lee, Anna Y.; Sriskanthadevan, Shrivani; Sun, Hong; Wang, Xiaoming; Skrtic, Marko; Seneviratne, Ayesh; Cusimano, Maria; Jhas, Bozhena; Gronda, Marcela; MacLean, Neil; Cho, Eunice E.; Spagnuolo, Paul A.; Sharmeen, Sumaiya; Gebbia, Marinella; Urbanus, Malene; Eppert, Kolja; Dissanayake, Dilan; Jonet, Alexia; Dassonville-Klimpt, Alexandra; Li, Xiaoming; Datti, Alessandro; Ohashi, Pamela S.; Wrana, Jeff; Rogers, Ian; Sonnet, Pascal; Ellis, William Y.; Corey, Seth J.; Eaves, Connie; Minden, Mark D.; Wang, Jean C.Y.; Dick, John E.; Nislow, Corey; Giaever, Guri; Schimmer, Aaron D.

    2012-01-01

    Despite efforts to understand and treat acute myeloid leukemia (AML), there remains a need for more comprehensive therapies to prevent AML-associated relapses. To identify new therapeutic strategies for AML, we screened a library of on- and off-patent drugs and identified the antimalarial agent mefloquine as a compound that selectively kills AML cells and AML stem cells in a panel of leukemia cell lines and in mice. Using a yeast genome-wide functional screen for mefloquine sensitizers, we identified genes associated with the yeast vacuole, the homolog of the mammalian lysosome. Consistent with this, we determined that mefloquine disrupts lysosomes, directly permeabilizes the lysosome membrane, and releases cathepsins into the cytosol. Knockdown of the lysosomal membrane proteins LAMP1 and LAMP2 resulted in decreased cell viability, as did treatment of AML cells with known lysosome disrupters. Highlighting a potential therapeutic rationale for this strategy, leukemic cells had significantly larger lysosomes compared with normal cells, and leukemia-initiating cells overexpressed lysosomal biogenesis genes. These results demonstrate that lysosomal disruption preferentially targets AML cells and AML progenitor cells, providing a rationale for testing lysosomal disruption as a novel therapeutic strategy for AML. PMID:23202731

  17. A novel double-targeted nondrug delivery system for targeting cancer stem cells

    Directory of Open Access Journals (Sweden)

    Qiao S

    2016-12-01

    Full Text Available Shupei Qiao,1,* Yufang Zhao,1,* Shuai Geng,2,* Yong Li,1,* Xiaolu Hou,1,3 Yi Liu,1 Feng-Huei Lin,4,5 Lifen Yao,6 Weiming Tian1 1School of Life Science and Technology, Harbin Institute of Technology, 2Department of Pharmacology, Harbin Medical University, 3Department of Cardiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China; 4Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan; 5Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan; 6Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China *These authors contributed equally to this work Abstract: Instead of killing cancer stem cells (CSCs, the conventional chemotherapy used for cancer treatment promotes the enrichment of CSCs, which are responsible for tumor growth, metastasis, and recurrence. However, most therapeutic agents are only able to kill a small proportion of CSCs by targeting one or two cell surface markers or dysregulated CSC pathways, which are usually shared with normal stem cells (NSCs. In this study, we developed a novel nondrug delivery system for the dual targeting of CSCs by conjugating hyaluronic acid (HA and grafting the doublecortin-like kinase 1 (DCLK1 monoclonal antibody to the surface of poly(ethylene glycol (PEG–poly(d,l-lactide-co-glycolide (PLGA nanoparticles (NPs, which can specifically target CD44 receptors and the DCLK1 surface marker – the latter was shown to possess the capacity to distinguish between CSCSs and NSCs. The size and morphology of these NPs were characterized by dynamic light scattering (DLS, transmission electron microscopy (TEM, and scanning electron microscopy (SEM. This was followed by studies of NP encapsulation efficiency and in vitro drug release properties. Then, the cytotoxicity of the NPs was tested via Cell Counting Kit-8 assay. Finally

  18. Targeted cytotoxic therapy kills persisting HIV infected cells during ART.

    Science.gov (United States)

    Denton, Paul W; Long, Julie M; Wietgrefe, Stephen W; Sykes, Craig; Spagnuolo, Rae Ann; Snyder, Olivia D; Perkey, Katherine; Archin, Nancie M; Choudhary, Shailesh K; Yang, Kuo; Hudgens, Michael G; Pastan, Ira; Haase, Ashley T; Kashuba, Angela D; Berger, Edward A; Margolis, David M; Garcia, J Victor

    2014-01-01

    Antiretroviral therapy (ART) can reduce HIV levels in plasma to undetectable levels, but rather little is known about the effects of ART outside of the peripheral blood regarding persistent virus production in tissue reservoirs. Understanding the dynamics of ART-induced reductions in viral RNA (vRNA) levels throughout the body is important for the development of strategies to eradicate infectious HIV from patients. Essential to a successful eradication therapy is a component capable of killing persisting HIV infected cells during ART. Therefore, we determined the in vivo efficacy of a targeted cytotoxic therapy to kill infected cells that persist despite long-term ART. For this purpose, we first characterized the impact of ART on HIV RNA levels in multiple organs of bone marrow-liver-thymus (BLT) humanized mice and found that antiretroviral drug penetration and activity was sufficient to reduce, but not eliminate, HIV production in each tissue tested. For targeted cytotoxic killing of these persistent vRNA(+) cells, we treated BLT mice undergoing ART with an HIV-specific immunotoxin. We found that compared to ART alone, this agent profoundly depleted productively infected cells systemically. These results offer proof-of-concept that targeted cytotoxic therapies can be effective components of HIV eradication strategies.

  19. Trastuzumab Sensitizes Ovarian Cancer Cells to EGFR-targeted Therapeutics

    Directory of Open Access Journals (Sweden)

    Wilken Jason A

    2010-03-01

    Full Text Available Abstract Background Early studies have demonstrated comparable levels of HER2/ErbB2 expression in both breast and ovarian cancer. Trastuzumab (Herceptin, a therapeutic monoclonal antibody directed against HER2, is FDA-approved for the treatment of both early and late stage breast cancer. However, clinical studies of trastuzumab in epithelial ovarian cancer (EOC patients have not met the same level of success. Surprisingly, however, no reports have examined either the basis for primary trastuzumab resistance in ovarian cancer or potential ways of salvaging trastuzumab as a potential ovarian cancer therapeutic. Methods An in vitro model of primary trastuzumab-resistant ovarian cancer was created by long-term culture of HER2-positive ovarian carcinoma-derived cell lines with trastuzumab. Trastuzumab treated vs. untreated parental cells were compared for HER receptor expression, trastuzumab sensitivity, and sensitivity to other HER-targeted therapeutics. Results In contrast to widely held assumptions, here we show that ovarian cancer cells that are not growth inhibited by trastuzumab are still responsive to trastuzumab. Specifically, we show that responsiveness to alternative HER-targeted inhibitors, such as gefitinib and cetuximab, is dramatically potentiated by long-term trastuzumab treatment of ovarian cancer cells. HER2-positive ovarian carcinoma-derived cells are, therefore, not "unresponsive" to trastuzumab as previously assumed, even when they not growth inhibited by this drug. Conclusions Given the recent success of EGFR-targeted therapeutics for the treatment of other solid tumors, and the well-established safety profile of trastuzumab, results presented here provide a rationale for re-evaluation of trastuzumab as an experimental ovarian cancer therapeutic, either in concert with, or perhaps as a "primer" for EGFR-targeted therapeutics.

  20. Alpinetin targets glioma stem cells by suppressing Notch pathway.

    Science.gov (United States)

    Wang, Jianpeng; Yan, Zhiyong; Liu, Xia; Che, Shusheng; Wang, Chao; Yao, Weicheng

    2016-07-01

    Glioma is among the most common human malignancies with poor prognosis. Glioma stem cells (GSCs) are the culprit of glioma, suggesting that GSCs are potential therapeutic targets. Notch signaling pathway plays a pivotal role for the function of GSCs, implying that suppression of Notch pathway may be an effective strategy for GSC-targeting therapy. In this study, we found that alpinetin, a natural compound, can suppress the proliferation and invasiveness of GSCs and induce apoptosis in GSCs. Immunoblot analysis and luciferase assay revealed that Notch signaling was suppressed by alpinetin. Furthermore, restoration of Notch signaling activity rescued the effect of alpinetin on GSC's function. The anti-tumor activity of alpinetin was further confirmed in an animal model. Collectively, targeting of GSC by alpinetin is an effective strategy for glioma therapy.

  1. Targeted therapy in non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    Shou-Ching Tang

    2004-01-01

    @@ 1 Introduction Recent progress in molecular biology has enabled us to better understand the molecular mechanism underlying pathogenesis of human malignancy including lung cancer. Sequencing of human genome has identified many oncogenes and tumor suppressor genes,giving us a better understanding of the molecular events leading to the formation, progression, metastasis, and the development of drug resistance in human lung cancer. In addition, many signal transduction pathways have been discovered that play important roles in lung cancer. Novel strategy of anti-cancer drug development now involves the identification and development of targeted therapy that interrupts one or more than one pathways or cross-talk among different signal transduction pathways. In addition, efforts are underway that combine the traditional cytotoxic (non-targeted) agents with the biological (targeted) therapy to increase the response rate and survival in patients with lung cancer, especially advanced non-small cell lung cancer (NSCLC).

  2. Cancer immunotherapy: nanodelivery approaches for immune cell targeting and tracking

    Science.gov (United States)

    Conniot, João; Silva, Joana; Fernandes, Joana; Silva, Liana; Gaspar, Rogério; Brocchini, Steve; Florindo, Helena; Barata, Teresa

    2014-11-01

    Cancer is one of the most common diseases afflicting people globally. New therapeutic approaches are needed due to the complexity of cancer as a disease. Many current treatments are very toxic and have modest efficacy at best. Increased understanding of tumor biology and immunology has allowed the development of specific immunotherapies with minimal toxicity. It is important to highlight the performance of monoclonal antibodies, immune adjuvants, vaccines and cell-based treatments. Although these approaches have shown varying degrees of clinical efficacy, they illustrate the potential to develop new strategies. Targeted immunotherapy is being explored to overcome the heterogeneity of malignant cells and the immune suppression induced by both the tumor and its microenvironment. Nanodelivery strategies seek to minimize systemic exposure to target therapy to malignant tissue and cells. Intracellular penetration has been examined through the use of functionalized particulates. These nano-particulate associated medicines are being developed for use in imaging, diagnostics and cancer targeting. Although nano-particulates are inherently complex medicines, the ability to confer, at least in principle, different types of functionality allows for the plausible consideration these nanodelivery strategies can be exploited for use as combination medicines. The development of targeted nanodelivery systems in which therapeutic and imaging agents are merged into a single platform is an attractive strategy. Currently, several nanoplatform-based formulations, such as polymeric nanoparticles, micelles, liposomes and dendrimers are in preclinical and clinical stages of development. Herein, nanodelivery strategies presently investigated for cancer immunotherapy, cancer targeting mechanisms and nanocarrier functionalization methods will be described. We also intend to discuss the emerging nano-based approaches suitable to be used as imaging techniques and as cancer treatment options.

  3. Delivery of Therapeutic RNAs Into Target Cells IN VIVO

    Science.gov (United States)

    Ng, Mei Ying; Hagen, Thilo

    2014-02-01

    RNA-based therapy is one of the most promising approaches to treat human diseases. Specifically, the use of short interfering RNA (siRNA) siRNA and microRNA (miRNA) mimics for in vivo RNA interference has immense potential as it directly lowers the expression of the therapeutic target protein. However, there are a number of major roadblocks to the successful implementation of siRNA and other RNA based therapies in the clinic. These include the instability of RNAs in vivo and the difficulty to efficiently deliver the RNA into the target cells. Hence, various innovative approaches have been taken over the years to develop effective RNA delivery methods. These methods include liposome-, polymeric nanoparticle- and peptide-mediated cellular delivery. In a recent innovative study, bioengineered bacterial outer membrane vesicles were used as vehicles for effective delivery of siRNA into cells in vivo.

  4. The polarized double cell target of the SMC

    CERN Document Server

    Adams, D; Arik, E; Arvidson, A; Badelek, B; Ballintijn, M K; Bardin, G; Baum, G; Berglund, P; Betev, L; Bird, I G; Birsa, R; Björkholm, P; Bonner, B E; De Botton, N R; Boutemeur, M; Bradamante, Franco; Bravar, A; Bressan, A; Bültmann, S; Burtin, E; Cavata, C; Crabb, D; Cranshaw, J; Çuhadar-Dönszelmann, T; Dalla Torre, S; Van Dantzig, R; Derro, B R; Deshpande, A A; Dhawan, S K; Dulya, C M; Dyring, A; Eichblatt, S; Faivre, Jean-Claude; Fasching, D; Feinstein, F; Fernández, C; Forthmann, S; Frois, Bernard; Gallas, A; Garzón, J A; Gaussiran, T; Gilly, H; Giorgi, M A; von Goeler, E; Görtz, S; Gracia, G; De Groot, N; Grosse-Perdekamp, M; Gülmez, E; Haft, K; Von Harrach, D; Hasegawa, T; Hautle, P; Hayashi, N; Heusch, C A; Horikawa, N; Hughes, V W; Igo, G; Ishimoto, S; Iwata, T; Kabuss, E M; Kageya, T; Karev, A G; Kessler, H J; Ketel, T; Kiryluk, J; Kishi, A; Kiselev, Yu F; Klostermann, L; Krämer, Dietrich; Krivokhizhin, V G; Kröger, W; Kurek, K; Kyynäräinen, J; Lamanna, M; Landgraf, U; Layda, T; Le Goff, J M; Lehár, F; de Lesquen, A; Lichtenstadt, J; Lindqvist, T; Litmaath, M; Loewe, M; Magnon, A; Mallot, G K; Marie, F; Martin, A; Martino, J; Matsuda, T; Mayes, B W; McCarthy, J S; Medved, K S; Meyer, W T; Van Middelkoop, G; Miller, D; Miyachi, Y; Mori, K; Moromisato, J H; Nassalski, J P; Naumann, Lutz; Neganov, B S; Niinikoski, T O; Oberski, J; Ogawa, A; Ozben, C; Parks, D P; Pereira, H; Penzo, Aldo L; Perrot-Kunne, F; Peshekhonov, V D; Piegaia, R; Pinsky, L; Platchkov, S K; Pló, M; Pose, D; Postma, H; Pretz, J; Pussieux, T; Pyrlik, J; Rädel, G; Reyhancan, I; Reicherz, G; Rijllart, A; Roberts, J B; Rock, S E; Rodríguez, M; Rondio, Ewa; Rosado, A; Roscherr, B; Sabo, I; Saborido, J; Sandacz, A; Savin, I A; Schiavon, R P; Schiller, A; Schüler, K P; Segel, R E; Seitz, R; Semertzidis, Y K; Sever, F; Shanahan, P; Sichtermann, E P; Simeoni, F; Smirnov, G I; Staude, A; Steinmetz, A; Stiegler, U; Stuhrmann, H B; Szleper, M; Teichert, K M; Tessarotto, F; Thers, D; Tlaczala, W; Trentalange, S; Tripet, A; Ünel, G; Velasco, M; Vogt, J; Voss, Rüdiger; Weinstein, R; Whitten, C; Windmolders, R; Willumeit, R; Wislicki, W; Witzmann, A; Zanetti, A M; Zaremba, K; Zhao, J

    1999-01-01

    The polarized target of the Spin Muon Collaboration at CERN was used for deep inelastic muon scattering experiments during 1993 to 1996 with a polarized muon beam to investigate the spin structure of the nucleon. Most of the experiments were carried out with longitudinal target polarization and 190 GeV muons, and some were done with transverse polarization and 100 GeV muons. Protons as well as deuterons were polarized by dynamic nuclear polarization (DNP) in three kinds of solid materials $-$ butanol, ammonia, and deuterated butanol, with maximum degrees of polarization of 94, 91, and 60 \\%, respectively. Considerable attention was paid to the accuracies of the NMR polarization measurements and their analyses. The achieved accuracies were between 2.0 and 3.2 \\%. The SMC target system with two cells of opposite polarizations, each cell 65 cm long and 5 cm in diameter, constitutes the largest polarized target system ever built and facilitates accurate spin asymmetry measurements. The design considerations, the ...

  5. Diffusion tensor driven contour closing for cell microinjection targeting.

    Science.gov (United States)

    Becattini, Gabriele; Mattos, Leonardo S; Caldwell, Darwin G

    2010-01-01

    This article introduces a novel approach to robust automatic detection of unstained living cells in bright-field (BF) microscope images with the goal of producing a target list for an automated microinjection system. The overall image analysis process is described and includes: preprocessing, ridge enhancement, image segmentation, shape analysis and injection point definition. The developed algorithm implements a new version of anisotropic contour completion (ACC) based on the partial differential equation (PDE) for heat diffusion which improves the cell segmentation process by elongating the edges only along their tangent direction. The developed ACC algorithm is equivalent to a dilation of the binary edge image with a continuous elliptic structural element that takes into account local orientation of the contours preventing extension towards normal direction. Experiments carried out on real images of 10 to 50 microm CHO-K1 adherent cells show a remarkable reliability in the algorithm along with up to 85% success for cell detection and injection point definition.

  6. Topical vaccination with functionalized particles targeting dendritic cells.

    Science.gov (United States)

    Baleeiro, Renato B; Wiesmüller, Karl-Heinz; Reiter, Yoran; Baude, Barbara; Dähne, Lars; Patzelt, Alexa; Lademann, Jürgen; Barbuto, José A; Walden, Peter

    2013-08-01

    Needle-free vaccination, for reasons of safety, economy, and convenience, is a central goal in vaccine development, but it also needs to meet the immunological requirements for efficient induction of prophylactic and therapeutic immune responses. Combining the principles of noninvasive delivery to dendritic cells (DCs) through skin and the immunological principles of cell-mediated immunity, we developed microparticle-based topical vaccines. We show here that the microparticles are efficient carriers for coordinated delivery of the essential vaccine constituents to DCs for cross-presentation of the antigens and stimulation of T-cell responses. When applied to the skin, the microparticles penetrate into hair follicles and target the resident DCs, the immunologically most potent cells and site for induction of efficient immune responses. The microparticle vaccine principle can be applied to different antigen formats such as peptides and proteins, or nucleic acids coding for the antigens.

  7. Innovative T Cell-Targeted Therapy for Ovarian Cancer

    Science.gov (United States)

    2014-10-01

    cell specificity by introducing a tumor-specific chimeric antigen receptor. Blood 2010; 116(7): 1035-44. 14. Kalos M, Levine BL, Porter DL, Katz S...leukemia. Sci Transl Med 2011; 3(95): 95ra73. 15. Porter DL, Levine BL, Kalos M, Bagg A, June CH. Chimeric antigen receptor-modified T cells in chronic...pool ( diamonds ) of all three antibodies were used to block killing of Jurkat (left), IGROV1 (middle), or OC314 (right) tumor targets antibodies at 0.3

  8. A novel gene delivery system targeting cells expressing VEGF receptors

    Institute of Scientific and Technical Information of China (English)

    LIJUNMIN; JINGCHULUO; 等

    1999-01-01

    Two ligand oligopeptides GV1 and GV2 were designed according to the putative binding region of VEGF to its receptors.GV1,GV2 and endosome releasing oligopeptide HA20 were conjugated with poly-L-lysine or protamine and the resulting conjugates could interact with DNA in a noncovalent bond to form a complex.Using pSV2-β-galactosidase as a reporter gene,it has been demonstrated that exogenous gene was transferred into bovine aortic arch-derived endothelial cells (ABAE) and human malignant melanoma cell lines (A375) in vitro.In vivo experiments,exogenous gene was transferred into tumor vascular endothelial cells and tumor cells of subcutaneously transplanted human colon cancer LOVO,human malignant melanoma A375 and human hepatoma graft in nude mice.This system could also target gene to intrahepatically transplanted human hepatoma injected via portal vein in nude mice.These results are correlated with the relevant receptors(flt-1,flk-1/KDR) expression on the targeted cells and tissues.

  9. The cell's nucleolus: an emerging target for chemotherapeutic intervention.

    Science.gov (United States)

    Pickard, Amanda J; Bierbach, Ulrich

    2013-09-01

    The transient nucleolus plays a central role in the up-regulated synthesis of ribosomal RNA (rRNA) to sustain ribosome biogenesis, a hallmark of aberrant cell growth. This function, in conjunction with its unique pathohistological features in malignant cells and its ability to mediate apoptosis, renders this sub-nuclear structure a potential target for chemotherapeutic agents. In this Minireview, structurally and functionally diverse small molecules are discussed that have been reported to either interact with the nucleolus directly or perturb its function indirectly by acting on its dynamic components. These molecules include all major classes of nucleic-acid-targeted agents, antimetabolites, kinase inhibitors, anti-inflammatory drugs, natural product antibiotics, oligopeptides, as well as nanoparticles. Together, these molecules are invaluable probes of structure and function of the nucleolus. They also provide a unique opportunity to develop novel strategies for more selective and therefore better-tolerated chemotherapeutic intervention. In this regard, inhibition of RNA polymerase-I-mediated rRNA synthesis appears to be a promising mechanism for killing cancer cells. The recent development of molecules targeted at G-quadruplex-forming rRNA gene sequences, which are currently undergoing clinical trials, seems to attest to the success of this approach.

  10. Therapies targeting cancer stem cells: Current trends and future challenges

    Institute of Scientific and Technical Information of China (English)

    Denisa; L; Dragu; Laura; G; Necula; Coralia; Bleotu; Carmen; C; Diaconu; Mihaela; Chivu-Economescu

    2015-01-01

    Traditional therapies against cancer, chemo- and radiotherapy, have multiple limitations that lead to treatment failure and cancer recurrence. These limitations are related to systemic and local toxicity, while treatment failure and cancer relapse are due to drug resistance and self-renewal, properties of a small population of tumor cells called cancer stem cells(CSCs). These cells are involved in cancer initiation, maintenance, metastasis and recurrence. Therefore, in order to develop efficient treatments that can induce a longlasting clinical response preventing tumor relapse it is important to develop drugs that can specifically target and eliminate CSCs. Recent identification of surface markers and understanding of molecular feature associated with CSC phenotype helped with the design of effective treatments. In this review we discuss targeting surface biomarkers, signaling pathways that regulate CSCs self-renewal and differentiation, drug-efflux pumps involved in apoptosis resistance, microenvironmental signals that sustain CSCs growth, manipulation of mi RNA expression, and induction of CSCs apoptosis and differentiation, with specific aim to hamper CSCs regeneration and cancer relapse. Some of these agents are under evaluation in preclinical and clinical studies, most of them for using in combination with traditional therapies. The combined therapy using conventional anticancer drugs with CSCs-targeting agents, may offer a promising strategy for management and eradication of different types of cancers.

  11. Improvement of desolvation and resilience of alginate binders for Si-based anodes in a lithium ion battery by calcium-mediated cross-linking.

    Science.gov (United States)

    Yoon, Jihee; Oh, Dongyeop X; Jo, Changshin; Lee, Jinwoo; Hwang, Dong Soo

    2014-12-14

    Si-based anodes in lithium ion batteries (LIBs) have exceptionally high theoretical capacity, but the use of a Si-based anode in LIBs is problematic because the charging-discharging process can fracture the Si particles. Alginate and its derivatives show promise as Si particle binders in the anode. We show that calcium-mediated "egg-box" electrostatic cross-linking of alginate improves toughness, resilience, electrolyte desolvation of the alginate binder as a Si-binder for LIBs. Consequently, the improved mechanical properties of the calcium alginate binder compared to the sodium alginate binder and other commercial binders extend the lifetime and increase the capacity of Si-based anodes in LIBs.

  12. Targeting cancer stem cells with p53 modulators

    Science.gov (United States)

    Hayashi, Ryo; Appella, Ettore; Kopelovich, Levy; DeLeo, Albert B.

    2016-01-01

    Cancer stem cells (CSC) typically over-express aldehyde dehydrogenase (ALDH). Thus, ALDHbright tumor cells represent targets for developing novel cancer prevention/treatment interventions. Loss of p53 function is a common genetic event during cancer development wherein small molecular weight compounds (SMWC) that restore p53 function and reverse tumor growth have been identified. Here, we focused on two widely studied p53 SMWC, CP-31398 and PRIMA-1, to target ALDHbright CSC in human breast, endometrial and pancreas carcinoma cell lines expressing mutant or wild type (WT) p53. CP-31398 and PRIMA-1 significantly reduced CSC content and sphere formation by these cell lines in vitro. In addition, these agents were more effective in vitro against CSC compared to cisplatin and gemcitabine, two often-used chemotherapeutic agents. We also tested a combinatorial treatment in methylcholantrene (MCA)-treated mice consisting of p53 SMWC and p53-based vaccines. Yet using survival end-point analysis, no increased efficacy in the presence of either p53 SMWC alone or with vaccine compared to vaccine alone was observed. These results may be due, in part, to the presence of immune cells, such as activated lymphocytes expressing WT p53 at levels comparable to some tumor cells, wherein further increase of p53 expression by p53 SMWC may alter survival of these immune cells and negatively impact an effective immune response. Continuous exposure of mice to MCA may have also interfered with the action of these p53 SMWC, including potential direct interaction with MCA. Nonetheless, the effect of p53 SMWC on CSC and cancer treatment remains of great interest. PMID:27074569

  13. Radioprotection of targeted and bystander cells by methylproamine

    Energy Technology Data Exchange (ETDEWEB)

    Burdak-Rothkamm, Susanne [Queen' s University Belfast, Centre for Cancer Research and Cell Biology, Belfast (United Kingdom); Oxford University Hospitals, Cellular Pathology, Oxford (United Kingdom); Smith, Andrea; Lobachevsky, Pavel; Martin, Roger [Peter MacCallum Cancer Centre, Molecular Radiation Biology Laboratory, Melbourne (Australia); University of Melbourne, The Sir Peter MacCallum Department of Oncology, Melbourne (Australia); Prise, Kevin M. [Queen' s University Belfast, Centre for Cancer Research and Cell Biology, Belfast (United Kingdom)

    2014-09-23

    Radioprotective agents are of interest for application in radiotherapy for cancer and in public health medicine in the context of accidental radiation exposure. Methylproamine is the lead compound of a class of radioprotectors which act as DNA binding anti-oxidants, enabling the repair of transient radiation-induced oxidative DNA lesions. This study tested methylproamine for the radioprotection of both directly targeted and bystander cells. T98G glioma cells were treated with 15 μM methylproamine and exposed to {sup 137}Cs γ-ray/X-ray irradiation and He{sup 2+} microbeam irradiation. Radioprotection of directly targeted cells and bystander cells was measured by clonogenic survival or γH2AX assay. Radioprotection of directly targeted T98G cells by methylproamine was observed for {sup 137}Cs γ-rays and X-rays but not for He{sup 2+} charged particle irradiation. The effect of methylproamine on the bystander cell population was tested for both X-ray irradiation and He{sup 2+} ion microbeam irradiation. The X-ray bystander experiments were carried out by medium transfer from irradiated to non-irradiated cultures and three experimental designs were tested. Radioprotection was only observed when recipient cells were pretreated with the drug prior to exposure to the conditioned medium. In microbeam bystander experiments targeted and nontargeted cells were co-cultured with continuous methylproamine treatment during irradiation and postradiation incubation; radioprotection of bystander cells was observed. Methylproamine protected targeted cells from DNA damage caused by γ-ray or X-ray radiation but not He{sup 2+} ion radiation. Protection of bystander cells was independent of the type of radiation which the donor population received. (orig.) [German] Radioprotektive Agenzien sind sowohl in der Strahlentherapie von Krebserkrankungen als auch im Strahlenschutz im Zusammenhang mit akzidenteller Exposition von Bedeutung. Methylproamine ist die Leitsubstanz einer Klasse von

  14. New small molecules targeting apoptosis and cell viability in osteosarcoma.

    Directory of Open Access Journals (Sweden)

    Doris Maugg

    Full Text Available Despite the option of multimodal therapy in the treatment strategies of osteosarcoma (OS, the most common primary malignant bone tumor, the standard therapy has not changed over the last decades and still involves multidrug chemotherapy and radical surgery. Although successfully applied in many patients a large number of patients eventually develop recurrent or metastatic disease in which current therapeutic regimens often lack efficacy. Thus, new therapeutic strategies are urgently needed. In this study, we performed a phenotypic high-throughput screening campaign using a 25,000 small-molecule diversity library to identify new small molecules selectively targeting osteosarcoma cells. We could identify two new small molecules that specifically reduced cell viability in OS cell lines U2OS and HOS, but affected neither hepatocellular carcinoma cell line (HepG2 nor primary human osteoblasts (hOB. In addition, the two compounds induced caspase 3 and 7 activity in the U2OS cell line. Compared to conventional drugs generally used in OS treatment such as doxorubicin, we indeed observed a greater sensitivity of OS cell viability to the newly identified compounds compared to doxorubicin and staurosporine. The p53-negative OS cell line Saos-2 almost completely lacked sensitivity to compound treatment that could indicate a role of p53 in the drug response. Taken together, our data show potential implications for designing more efficient therapies in OS.

  15. Engineering tumor cell targeting in nanoscale amyloidal materials

    Science.gov (United States)

    Unzueta, Ugutz; Seras-Franzoso, Joaquin; Virtudes Céspedes, María; Saccardo, Paolo; Cortés, Francisco; Rueda, Fabián; Garcia-Fruitós, Elena; Ferrer-Miralles, Neus; Mangues, Ramon; Vázquez, Esther; Villaverde, Antonio

    2017-01-01

    Bacterial inclusion bodies are non-toxic, mechanically stable and functional protein amyloids within the nanoscale size range that are able to naturally penetrate into mammalian cells, where they deliver the embedded protein in a functional form. The potential use of inclusion bodies in protein delivery or protein replacement therapies is strongly impaired by the absence of specificity in cell binding and penetration, thus preventing targeting. To address this issue, we have here explored whether the genetic fusion of two tumor-homing peptides, the CXCR4 ligands R9 and T22, to an inclusion body-forming green fluorescent protein (GFP), would keep the interaction potential and the functionality of the fused peptides and then confer CXCR4 specificity in cell binding and further uptake of the materials. The fusion proteins have been well produced in Escherichia coli in their full-length form, keeping the potential for fluorescence emission of the partner GFP. By using specific inhibitors of CXCR4 binding, we have demonstrated that the engineered protein particles are able to penetrate CXCR4+ cells, in a receptor-mediated way, without toxicity or visible cytopathic effects, proving the availability of the peptide ligands on the surface of inclusion bodies. Since no further modification is required upon their purification, the biological production of genetically targeted inclusion bodies opens a plethora of cost-effective possibilities in the tissue-specific intracellular transfer of functional proteins through the use of structurally and functionally tailored soft materials.

  16. Targeting Gallium to Cancer Cells through the Folate Receptor

    Directory of Open Access Journals (Sweden)

    Nerissa Viola-Villegas

    2008-01-01

    Full Text Available The development of gallium(III compounds as anti-cancer agents for both treatment and diagnosis is a rapidly developing field of research. Problems remain in exploring the full potential of gallium(III as a safe and successful therapeutic agent or as an imaging agent. One of the major issues is that gallium(III compounds have little tropism for cancer cells. We have combined the targeting properties of folic acid (FA with long chain liquid polymer poly(ethylene glycol (PEG ‘spacers’. This FA-PEG unit has been coupled to the gallium coordination complex of 1,4,7,10-tetraazacyclo-dodecane-N,N′,N′′,N′′′-tetraacetic acid (DOTA through amide linkages for delivery into target cells overexpressing the folate receptor (FR. In vitro cytotoxicity assays were conducted against a multi-drug resistant ovarian cell line (A2780/AD that overexpresses the FR and contrasted against a FR free Chinese hamster ovary (CHO cell line. Results are rationalized taking into account stability studies conducted in RPMI 1640 media and HEPES buffer at pH 7.4.

  17. Lipoproteins tethered dendrimeric nanoconstructs for effective targeting to cancer cells

    Science.gov (United States)

    Jain, Anupriya; Jain, Keerti; Mehra, Neelesh Kumar; Jain, N. K.

    2013-10-01

    In the present investigation, poly (propylene imine) dendrimers up to fifth generation (PPI G5.0) were synthesized using ethylene diamine and acrylonitrile. Lipoproteins (high-density lipoprotein; HDL and low-density lipoprotein; LDL) were isolated from human plasma by discontinuous density gradient ultracentrifugation, characterized and tethered to G5.0 PPI dendrimers to construct LDL- and HDL-conjugated dendrimeric nanoconstructs for tumor-specific delivery of docetaxel. Developed formulations showed sustained release characteristics in in vitro drug release and in vivo pharmacokinetic studies. The cancer targeting potential of lipoprotein coupled dendrimers was investigated by ex vivo cytotoxicity and cell uptake studies using human hepatocellular carcinoma cell lines (HepG2 cells) and biodistribution studies in albino rats of Sprague-Dawley strain. Lipoprotein anchored dendrimeric nanoconstructs showed significant uptake by cancer cells as well as higher biodistribution of docetaxel to liver and spleen. It is concluded that these precisely synthesized engineered dendrimeric nanoconstructs could serve as promising drug carrier for fighting with the fatal disease, i.e., cancer, attributed to their defined targeting and therapeutic potential.

  18. Lipoproteins tethered dendrimeric nanoconstructs for effective targeting to cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Anupriya; Jain, Keerti, E-mail: keertijain02@gmail.com; Mehra, Neelesh Kumar, E-mail: neelesh81mph@gmail.com; Jain, N. K., E-mail: dr.jnarendr@gmail.com [Dr. H. S. Gour University, Pharmaceutics Research Laboratory, Department of Pharmaceutical Sciences (India)

    2013-10-15

    In the present investigation, poly (propylene imine) dendrimers up to fifth generation (PPI G5.0) were synthesized using ethylene diamine and acrylonitrile. Lipoproteins (high-density lipoprotein; HDL and low-density lipoprotein; LDL) were isolated from human plasma by discontinuous density gradient ultracentrifugation, characterized and tethered to G5.0 PPI dendrimers to construct LDL- and HDL-conjugated dendrimeric nanoconstructs for tumor-specific delivery of docetaxel. Developed formulations showed sustained release characteristics in in vitro drug release and in vivo pharmacokinetic studies. The cancer targeting potential of lipoprotein coupled dendrimers was investigated by ex vivo cytotoxicity and cell uptake studies using human hepatocellular carcinoma cell lines (HepG2 cells) and biodistribution studies in albino rats of Sprague-Dawley strain. Lipoprotein anchored dendrimeric nanoconstructs showed significant uptake by cancer cells as well as higher biodistribution of docetaxel to liver and spleen. It is concluded that these precisely synthesized engineered dendrimeric nanoconstructs could serve as promising drug carrier for fighting with the fatal disease, i.e., cancer, attributed to their defined targeting and therapeutic potential.

  19. Target cell cyclophilins facilitate human papillomavirus type 16 infection.

    Directory of Open Access Journals (Sweden)

    Malgorzata Bienkowska-Haba

    2009-07-01

    Full Text Available Following attachment to primary receptor heparan sulfate proteoglycans (HSPG, human papillomavirus type 16 (HPV16 particles undergo conformational changes affecting the major and minor capsid proteins, L1 and L2, respectively. This results in exposure of the L2 N-terminus, transfer to uptake receptors, and infectious internalization. Here, we report that target cell cyclophilins, peptidyl-prolyl cis/trans isomerases, are required for efficient HPV16 infection. Cell surface cyclophilin B (CyPB facilitates conformational changes in capsid proteins, resulting in exposure of the L2 N-terminus. Inhibition of CyPB blocked HPV16 infection by inducing noninfectious internalization. Mutation of a putative CyP binding site present in HPV16 L2 yielded exposed L2 N-terminus in the absence of active CyP and bypassed the need for cell surface CyPB. However, this mutant was still sensitive to CyP inhibition and required CyP for completion of infection, probably after internalization. Taken together, these data suggest that CyP is required during two distinct steps of HPV16 infection. Identification of cell surface CyPB will facilitate the study of the complex events preceding internalization and adds a putative drug target for prevention of HPV-induced diseases.

  20. Neuroblastoma cell lines contain pluripotent tumor initiating cells that are susceptible to a targeted oncolytic virus.

    Directory of Open Access Journals (Sweden)

    Yonatan Y Mahller

    Full Text Available BACKGROUND: Although disease remission can frequently be achieved for patients with neuroblastoma, relapse is common. The cancer stem cell theory suggests that rare tumorigenic cells, resistant to conventional therapy, are responsible for relapse. If true for neuroblastoma, improved cure rates may only be achieved via identification and therapeutic targeting of the neuroblastoma tumor initiating cell. Based on cues from normal stem cells, evidence for tumor populating progenitor cells has been found in a variety of cancers. METHODOLOGY/PRINCIPAL FINDINGS: Four of eight human neuroblastoma cell lines formed tumorspheres in neural stem cell media, and all contained some cells that expressed neurogenic stem cell markers including CD133, ABCG2, and nestin. Three lines tested could be induced into multi-lineage differentiation. LA-N-5 spheres were further studied and showed a verapamil-sensitive side population, relative resistance to doxorubicin, and CD133+ cells showed increased sphere formation and tumorigenicity. Oncolytic viruses, engineered to be clinically safe by genetic mutation, are emerging as next generation anticancer therapeutics. Because oncolytic viruses circumvent typical drug-resistance mechanisms, they may represent an effective therapy for chemotherapy-resistant tumor initiating cells. A Nestin-targeted oncolytic herpes simplex virus efficiently replicated within and killed neuroblastoma tumor initiating cells preventing their ability to form tumors in athymic nude mice. CONCLUSIONS/SIGNIFICANCE: These results suggest that human neuroblastoma contains tumor initiating cells that may be effectively targeted by an oncolytic virus.

  1. A new prospect in cancer therapy: targeting cancer stem cells to eradicate cancer

    Institute of Scientific and Technical Information of China (English)

    Li-Sha Chen; An-Xin Wang; Bing Dong; Ke-Feng Pu; Li-Hua Yuan; Yi-Min Zhu

    2012-01-01

    According to the cancer stem cell theory,cancers can be initiated by cancer stem cells.This makes cancer stem cells prime targets for therapeutic intervention.Eradicating cancer stem cells by efficient targeting agents may have the potential to cure cancer.In this review,we summarize recent breakthroughs that have improved our understanding of cancer stem cells,and we discuss the therapeutic strategy of targeting cancer stem cells,a promising future direction for cancer stem cell research.

  2. Dendritic cell targeting vaccine for HPV-associated cancer

    Science.gov (United States)

    Yin, Wenjie; Duluc, Dorothée; Joo, HyeMee; Oh, SangKon

    2017-01-01

    Dendritic cells (DCs) are major antigen presenting cells that can efficiently prime and activate cellular immune responses. Delivering antigens to in vivo DCs has thus been considered as a promising strategy that could allow us to mount T cell-mediated therapeutic immunity against cancers in patients. Successful development of such types of cancer vaccines that can target in vivo DCs, however, requires a series of outstanding questions that need to be addressed. These include the proper selection of which DC surface receptors, specific DC subsets and DC activators that can further enhance the efficacy of vaccines by promoting effector T cell infiltration and retention in tumors and their actions against tumors. Supplementing these areas of research with additional strategies that can counteract tumor immune evasion mechanisms is also expected to enhance the efficacy of such therapeutic vaccines against cancers. After more than a decade of study, we have concluded that antigen targeting to DCs via CD40 to evoke cellular responses is more efficient than targeting antigens to the same types of DCs via eleven other DC surface receptors tested. In recent work, we have further demonstrated that a prototype vaccine (anti-CD40-HPV16.E6/7, a recombinant fusion protein of anti-human CD40 and HPV16.E6/7 protein) for HPV16-associated cancers can efficiently activate HPV16.E6/7-specific T cells, particularly CD8+ T cells, from the blood of HPV16+ head-and-neck cancer patients. Moreover, anti-CD40-HPV16.E6/7 plus poly(I:C) can mount potent therapeutic immunity against TC-1 tumor expressing HPV16.E6/7 protein in human CD40 transgenic mice. In this manuscript, we thus highlight our recent findings for the development of novel CD40 targeting immunotherapeutic vaccines for HPV16-associated malignancies. In addition, we further discuss several of key questions that still remain to be addressed for enhancing therapeutic immunity elicited by our prototype vaccine against HPV16

  3. Bacterial cell division as a target for new antibiotics.

    Science.gov (United States)

    Sass, Peter; Brötz-Oesterhelt, Heike

    2013-10-01

    Bacterial resistance to currently applied antibiotics complicates the treatment of infections and demands the evaluation of new strategies to counteract multidrug-resistant bacteria. In recent years, the inhibition of the bacterial divisome, mainly by targeting the central cell division mediator FtsZ, has been recognized as a promising strategy for antibiotic attack. New antibiotics were shown to either interfere with the natural dynamics and functions of FtsZ during the cell cycle or to activate a bacterial protease to degrade FtsZ and thus bring about bacterial death in a suicidal manner. Their efficacy in animal models of infection together with resistance-breaking properties prove the potential of such drugs and validate the inhibition of bacterial cell division as an attractive approach for antibiotic intervention.

  4. Targeting cancer stem cells by using the nanoparticles

    Directory of Open Access Journals (Sweden)

    Hong IS

    2015-09-01

    Full Text Available In-Sun Hong,1,2,* Gyu-Beom Jang,1,2,* Hwa-Yong Lee,3 Jeong-Seok Nam1,2 1Laboratory of Tumor Suppressor, Lee Gil Ya Cancer and Diabetes Institute, 2Department of Molecular Medicine, School of Medicine, Gachon University, Incheon, 3The Faculty of Liberal Arts, Jungwon University, Chungbuk, Republic of Korea *These authors contributed equally to this work Abstract: Cancer stem cells (CSCs have been shown to be markedly resistant to conventional cancer treatments such as chemotherapy and radiation therapy. Therefore, therapeutic strategies that selectively target CSCs will ultimately lead to better cancer treatments. Currently, accessible conventional therapeutic agents mainly eliminate the bulk tumor but do not eliminate CSCs. Therefore, the discovery and improvement of CSC-targeting therapeutic agents are necessary. Nanoparticles effectively inhibit multiple types of CSCs by targeting specific signaling pathways (Wnt/ß-catenin, Notch, transforming growth factor-ß, and hedgehog signaling and/or specific markers (aldehyde dehydrogenases, CD44, CD90, and CD133 critically involved in CSC function and maintenance. In this review article, we summarized a number of findings to provide current information about their therapeutic potential of nanoparticles in various cancer cell types and CSCs. Keywords: ALDH, Wnt/ß-catenin, Hedgehog, Notch, TGF-ß signaling, CD44, CD133

  5. Targeting Cell Death Pathways for Therapeutic Intervention in Kidney Diseases.

    Science.gov (United States)

    Garg, Jay P; Vucic, Domagoj

    2016-05-01

    Precise regulation of cell death and survival is essential for proper maintenance of organismal homeostasis, development, and the immune system. Deregulated cell death can lead to developmental defects, neuropathies, infections, and cancer. Kidney diseases, especially acute pathologies linked to ischemia-reperfusion injury, are among illnesses that profoundly are affected by improper regulation or execution of cell death pathways. Attempts to develop medicines for kidney diseases have been impacted by the complexity of these pathologies given the heterogeneous patient population and diverse etiologies. By analyzing cell death pathways activated in kidney diseases, we attempt to differentiate their importance for these pathologies with a goal of identifying those that have more profound impact and the best therapeutic potential. Although classic apoptosis still might be important, regulated necrosis pathways including necroptosis, ferroptosis, parthanatos, and mitochondrial permeability transition-associated cell death play a significantly role in kidney diseases, especially in acute kidney pathologies. Although targeting receptor-interacting protein 1 kinase appears to be the best therapeutic strategy, combination with inhibitors of other cell death pathways is likely to bring superior benefit and possible cure to patients suffering from kidney diseases.

  6. Suppressor T cells - a sensitive target of lead toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Hambach, A.; Stiller-Winkler, R.; Oberbarnscheidt, J.; Ewers, J.

    1983-01-01

    Studies were performed to investigate the effect of chronic low level lead exposure on the regulatory functions of T cells in the humoral immune response to sheep red blood cells (SRBC) in mice. Female mice were exposed to lead (as lead acetate) in the diet at 545 (group 1) and 2180 ppm (group 2) for 10 weeks. Lead exposure resulting in blood lead levels (PbB) of about 50 ..mu..g/100 g (group 1) produced a substantial increase of the number of IgG antibodies secreting spleen cells on days 3 and 4 after challenge. At the higher exposure level (group 2; PbB 60-80 ..mu..g/100 g) a suppression of the number of IgG plaque forming cells was observed. The IgM response was much smaller than the IgG response. Although differences between the group means were small, the results indicate that there also is an enhancement of the IgM response in the lower dosage group on days 3 and 4. In a second experiment the effect of in vivo lead exposure on antigenic competition was examined. Lead substantially reduced the effect of antigenic competition. Results of both experiments suggest that suppressor T cells rather than helper T cells may represent the primary target for lead. Throughout this study serum complement C3 levels were determined. Complement C3 levels tended to be reduced in the lead exposed groups before as well as after inocculation with SRBC. (orig.*.

  7. Suppressor T cells - a sensitive target of lead toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Hambach, A.; Stiller-Winkler, R.; Oberbarnscheidt, J.; Ewers, U.

    1983-01-01

    Studies were performed to investigate the effect of chronic low level lead exposure on the regulatory functions of T cells in the humoral immune response to sheep red blood cells (SRBC) in mice. Female mice were exposed to lead (as lead acetate) in the diet at 545 (group 1) and 2180 ppm (group 2) for 10 weeks. Lead exposure resulting in blood lead levels (PbB) of about 50 ..mu..g/100 g (group 1) produced a substantial increase of the number of IgG antibodies secreting spleen cells on days 3 and 4 after challenge. At the higher exposure level (group 2; PbB 60-80 ..mu..m/100 g) a suppression of the number of IgG plawue forming cells was observed. The IgM response was much smaller than the IgG response. Although differences between the group means were small, the results indicate that there also is an enhancement of the IgM response in the lower dosage group on days 3 and 4. In a second experiment the effect of in vivo lead exposure on antigenic competition was examined. Lead substantially reduced the effect of antigenic competition. Results of both experiments suggest that suppressor T cells rather than helper T cells may represent the primary target for lead. Throughout this study serum complement C3 levels were determined. Complement C3 levels tended to be reduced in the lead exposed groups before as well as after inocculation with SRBC.

  8. Folate-conjugated immunoglobulin targets melanoma tumor cells for NK cell effector functions

    Science.gov (United States)

    Skinner, Cassandra C.; McMichael, Elizabeth L.; Jaime-Ramirez, Alena C.; Abrams, Zachary B.; Lee, Robert J.; Carson, William E.

    2016-01-01

    The folate receptor (FR) is over-expressed on the vascular side of cancerous cells including those of the breast, ovaries, testes, and cervix. We hypothesized that a folate-conjugated immunoglobulin (F-IgG) would bind to the FR that is over-expressed on melanoma tumor cells to target these cells for lysis by natural killer (NK) cells. Folate receptor expression was confirmed in the Mel-39 (human melanoma) cell line by flow cytometry and immunoblot analysis, using KB (human oral epithelial) and F01 (human melanoma) as a positive and negative control, respectively. FR-positive and negative cell lines were treated with F-IgG or control immunoglobulin G (C-IgG) in the presence or absence of cytokines in order to determine NK cell ability to lyse FR-positive cell lines. NK cell activation was significantly upregulated and lysis of Mel 39 tumor cells enhanced following treatment with F-IgG, as compared to C-IgG at all effector:target (E:T) ratios (p<0.01). This trend was further enhanced by NK cell stimulation with the activating cytokine interleukin-12 (IL-12). NK cell production of cytokines such as interferon-gamma (IFN-γ), macrophage inflammatory protein 1 alpha (MIP-1α), and regulated on activation normal T-cell expressed and secreted (RANTES) were also significantly increased in response to co-stimulation with IL-12 stimulation and F-IgG-coated Mel 39 target cells, as compared to controls (p<0.01). In contrast, F-IgG did not bind to the FR-negative cell line F01 and had no significant effect on NK cell lysis or cytokine production. This research indicates the potential use of F-IgG for its ability to induce an immune response from NK cells against FR-positive melanoma tumor cells which can be further enhanced by the addition of cytokines. PMID:27035691

  9. Targeting proliferating cell nuclear antigen and its protein interactions induces apoptosis in multiple myeloma cells.

    Directory of Open Access Journals (Sweden)

    Rebekka Müller

    Full Text Available Multiple myeloma is a hematological cancer that is considered incurable despite advances in treatment strategy during the last decade. Therapies targeting single pathways are unlikely to succeed due to the heterogeneous nature of the malignancy. Proliferating cell nuclear antigen (PCNA is a multifunctional protein essential for DNA replication and repair that is often overexpressed in cancer cells. Many proteins involved in the cellular stress response interact with PCNA through the five amino acid sequence AlkB homologue 2 PCNA-interacting motif (APIM. Thus inhibiting PCNA's protein interactions may be a good strategy to target multiple pathways simultaneously. We initially found that overexpression of peptides containing the APIM sequence increases the sensitivity of cancer cells to contemporary therapeutics. Here we have designed a cell-penetrating APIM-containing peptide, ATX-101, that targets PCNA and show that it has anti-myeloma activity. We found that ATX-101 induced apoptosis in multiple myeloma cell lines and primary cancer cells, while bone marrow stromal cells and primary healthy lymphocytes were much less sensitive. ATX-101-induced apoptosis was caspase-dependent and cell cycle phase-independent. ATX-101 also increased multiple myeloma cells' sensitivity against melphalan, a DNA damaging agent commonly used for treatment of multiple myeloma. In a xenograft mouse model, ATX-101 was well tolerated and increased the anti-tumor activity of melphalan. Therefore, targeting PCNA by ATX-101 may be a novel strategy in multiple myeloma treatment.

  10. Advanced cell therapies: targeting, tracking and actuation of cells with magnetic particles.

    Science.gov (United States)

    Connell, John J; Patrick, P Stephen; Yu, Yichao; Lythgoe, Mark F; Kalber, Tammy L

    2015-01-01

    Regenerative medicine would greatly benefit from a new platform technology that enabled measurable, controllable and targeting of stem cells to a site of disease or injury in the body. Superparamagnetic iron-oxide nanoparticles offer attractive possibilities in biomedicine and can be incorporated into cells, affording a safe and reliable means of tagging. This review describes three current and emerging methods to enhance regenerative medicine using magnetic particles to guide therapeutic cells to a target organ; track the cells using MRI and assess their spatial localization with high precision and influence the behavior of the cell using magnetic actuation. This approach is complementary to the systemic injection of cell therapies, thus expanding the horizon of stem cell therapeutics.

  11. Tyrosine kinase inhibitors target cancer stem cells in renal cell cancer.

    Science.gov (United States)

    Czarnecka, Anna M; Solarek, Wojciech; Kornakiewicz, Anna; Szczylik, Cezary

    2016-03-01

    This study was designed to analyze the impact of multi-targeted tyrosine kinase inhibitors on the cancer stem cell subpopulation in renal cell cancer. The second objective was to evaluate the effect of tumor growth inhibition related to a tumor niche factor - oxygen deprivation - as hypoxia develops along with the anti-angiogenic activity of tyrosine kinase inhibitors in renal tumors. Cells were treated with tyrosine kinase inhibitors, sunitinib, sorafenib and axitinib, in 2D and 3D culture conditions. Cell proliferation along with drug toxicity were evaluated. It was shown that the proliferation rate of cancer stem cells was decreased by the tyrosine kinase inhibitors. The efficacy of the growth inhibition was limited by hypoxic conditions and 3D intratumoral cell-cell interactions. We conclude that understanding the complex molecular interaction feedback loops between differentiated cancer cells, cancer stem cells and the tumor microenvironment in 3D culture should aid the identification of novel treatment targets and to evalute the efficacy of renal cancer therapies. Cell-cell interaction may represent a critical microenvironmental factor regulating cancer stem cell self-renewal potential, enhancing the stem cell phenotype and limiting drug toxicity. At the same time the role of hypoxia in renal cancer stem cell biology is also significant.

  12. Specifically targeted gene therapy for small-cell lung cancer

    DEFF Research Database (Denmark)

    Christensen, C.L.; Zandi, R.; Gjetting, T.

    2009-01-01

    Small-cell lung cancer (SCLC) is a highly malignant disease with poor prognosis. Hence, there is great demand for new therapies that can replace or supplement the current available treatment regimes. Gene therapy constitutes a promising strategy and relies on the principle of introducing exogenous....... This review describes and discusses the current status of the application of gene therapy in relation to SCLC Udgivelsesdato: 2009/4...... DNA into malignant cells causing them to die. Since SCLC is a highly disseminated malignancy, the gene therapeutic agent must be administered systemically, obligating a high level of targeting of tumor tissue and the use of delivery vehicles designed for systemic circulation of the therapeutic DNA...

  13. Mannosylated biodegradable polyethyleneimine for targeted DNA delivery to dendritic cells

    Directory of Open Access Journals (Sweden)

    Sun X

    2012-06-01

    Full Text Available Xun Sun, Simu Chen, Jianfeng Han, Zhirong ZhangKey Laboratory of Drug Targeting and Drug Delivery System, Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu, People’s Republic of ChinaBackground: To establish a potential gene-delivery system with the ability to deliver plasmid DNA to dendritic cells (DCs more efficiently and specifically, we designed and synthesized a low-molecular-weight polyethyleneimine and triethyleneglycol polymer (PEI–TEG and a series of its mannosylated derivatives.Methods: PEI–TEG was synthesized from PEI2000 and PEI600 with TEG as the cross-linker. PEI–TEG was then linked to mannose via a phenylisothiocyanate bridge to obtain man-PEI–TEG conjugates. The DNA conveyance abilities of PEI–TEG, man-PEI–TEG, as well as control PEI25k were evaluated by measuring their zeta potential, particle size, and DNA-binding abilities. The in vitro cytotoxicity, cell uptake, and transfection efficiency of these PEI/DNA complexes were examined on the DC2.4 cell line. Finally, a maturation experiment evaluated the effect of costimulatory molecules CD40, CD80, and CD86 on murine bone marrow-derived DCs (BMDCs using flow cytometry.Results: PEI–TEG and man-PEI–TEG were successfully synthesized and were shown to retain the excellent properties of PEI25k for condensing DNA. Compared with PEI–TEG as well as PEI25k, the man-PEI–TEG had less cytotoxicity and performed better in both cellular uptake and transfection assays in vitro. The results of the maturation experiment showed that all the PEI/DNA complexes induced an adequate upregulation of surface markers for DC maturation.Conclusion: These results demonstrated that man-PEI–TEG can be employed as a DC-targeting gene-delivery system.Keywords: dendritic cells, DCs, mannose, polyethyleneimine, PEI, gene delivery

  14. Dendritic Cells as a Pharmacological Target of Traditional Chinese Medicine

    Institute of Scientific and Technical Information of China (English)

    Xin Chen; Lu Yang; O. M. Zack Howard; Joost J. Oppenheim

    2006-01-01

    Dendritic cells (DCs) represent a heterogeneous population of professional antigen-presenting cells (APCs) that play a central role in the initiation and regulation of immune responses. There is considerable evidence that DCs can be used as therapeutic targets for pharmacological modulation of immune responses. Traditional Chines emedicine (TCM) has a long-standing history of using herbal medicine in the treatment of variety of human diseases.Many of the clinical effects of TCM have reportedly been attributed to the up- or down-regulation of immune responses. Accumulating evidence indicates that TCM and its components can interfere with immune responses at the earliest stage by targeting key functions of DCs. Here, we review those published studies of TCM with respect to their effects on immunobiological functions of DCs. Investigations based on both chemical entities derived from TCM as well as TCM herbal mixtures are presented. These studies suggest that various TCM herbal medicines have the capacity to inhibit or promote major functions of DCs, such as differentiation, maturation, cytokine production, survival, antigen uptake and presentation as well as trafficking. These studies have revealed novel biological effects of TCM and documented the utility of this approach to discover novel biological modifier of DC functions derived from natural sources.

  15. Testicular cell junction: a novel target for male contraception.

    Science.gov (United States)

    Lee, Nikki P Y; Wong, Elissa W P; Mruk, Dolores D; Cheng, C Yan

    2009-01-01

    Even though various contraceptive methods are widely available, the number of unwanted pregnancies is still on the rise in developing countries, pressurizing the already resource limited nations. One of the major underlying reasons is the lack of effective, low cost, and safe contraceptives for couples. During the past decade, some studies were performed using animal models to decipher if the Sertoli-germ cell junction in the testis is a target for male fertility regulation. Some of these study models were based on the use of hormones and/or chemicals to disrupt the hypothalamic-pituitary-testicular axis (e.g., androgen-based implants or pills) and others utilized a panel of chemical entities or synthetic peptides to perturb spermatogenesis either reversibly or non-reversibly. Among them, adjudin, a potential male contraceptive, is one of the compounds exerting its action on the unique adherens junctions, known as ectoplasmic specializations, in the testis. Since the testis is equipped with inter-connected cell junctions, an initial targeting of one junction type may affect the others and these accumulative effects could lead to spermatogenic arrest. This review attempts to cover an innovative theme on how male infertility can be achieved by inducing junction instability and defects in the testis, opening a new window of research for male contraceptive development. While it will still take much time and effort of intensive investigation before a product can reach the consumable market, these findings have provided hope for better family planning involving men.

  16. Primary targets in photochemical inactivation of cells in culture

    Science.gov (United States)

    Berg, Kristian; Jones, Stuart G.; Prydz, Kristian; Moan, Johan

    1995-01-01

    The mechanisms of photoinactivation of NHIK 3025 cells in culture sensitized by tetrasulfonated phenylporphines (TPPS4) are described). Ultracentrifugation studies on postnuclear supernatants indicated that the intracellular distribution of TPPS4 resembles that of (beta) -N-acetyl-D-glucosaminidase ((beta) -AGA), a lysosomal marker enzyme, and that the cytosolic content of TPPS4 is below the detection limit of the ultracentrifugation method. Upon light exposure more than 90% of TPPS4 was lost from the lysosomal fractions, due to lysosomal rupture. The content of TPPS4 in the postnuclear supernatants was reduced by 30 - 40% upon exposure to light. This is most likely due to binding of TPPS4 to the nuclei, which were removed from the cell extracts before ultracentrifugation, after photochemical treatment. The unpolymerized form of tubulin seems to be an important target for the photochemical inactivation of NHIK 3025 cells. Since TPPS4 is mainly localized in lysosomes it was assumed that a dose of light disrupting a substantial number of lysosomes followed by microtubule depolymerization by nocodazole would enhance the sensitivity of the cells to photoinactivation. This was confirmed by using a colony-forming assay. The increased phototoxic effect exerted by such a treatment regime could be explained by an enhanced sensitivity of tubulin to light. Another cytosolic constituent, lactate dehydrogenase, was not photoinactivated by TPPS4 and light.

  17. Salinomycin as a Drug for Targeting Human Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Cord Naujokat

    2012-01-01

    Full Text Available Cancer stem cells (CSCs represent a subpopulation of tumor cells that possess self-renewal and tumor initiation capacity and the ability to give rise to the heterogenous lineages of malignant cells that comprise a tumor. CSCs possess multiple intrinsic mechanisms of resistance to chemotherapeutic drugs, novel tumor-targeted drugs, and radiation therapy, allowing them to survive standard cancer therapies and to initiate tumor recurrence and metastasis. Various molecular complexes and pathways that confer resistance and survival of CSCs, including expression of ATP-binding cassette (ABC drug transporters, activation of the Wnt/β-catenin, Hedgehog, Notch and PI3K/Akt/mTOR signaling pathways, and acquisition of epithelial-mesenchymal transition (EMT, have been identified recently. Salinomycin, a polyether ionophore antibiotic isolated from Streptomyces albus, has been shown to kill CSCs in different types of human cancers, most likely by interfering with ABC drug transporters, the Wnt/β-catenin signaling pathway, and other CSC pathways. Promising results from preclinical trials in human xenograft mice and a few clinical pilote studies reveal that salinomycin is able to effectively eliminate CSCs and to induce partial clinical regression of heavily pretreated and therapy-resistant cancers. The ability of salinomycin to kill both CSCs and therapy-resistant cancer cells may define the compound as a novel and an effective anticancer drug.

  18. Effects of small interfering RNAs targeting fascin on human esophageal squamous cell carcinoma cell lines

    Directory of Open Access Journals (Sweden)

    Garcia Jose

    2010-06-01

    Full Text Available Abstract Background Fascin induces membrane protrusions and cell motility. Fascin overexpression was associated with poor prognosis, and its downregulation reduces cell motility and invasiveness in esophageal squamous cell carcinoma (ESCC. Using a stable knockdown cell line, we revealed the effect of fascin on cell growth, cell adhesion and tumor formation. Methods We examined whether fascin is a potential target in ESCC using in vitro and in vivo studies utilizing a specific siRNA. We established a stable transfectant with downregulated fascin from KYSE170 cell line. Results The fascin downregulated cell lines showed a slower growth pattern by 40.3% (p In vivo, the tumor size was significantly smaller in the tumor with fascin knockdown cells than in mock cells by 95% at 30 days after inoculation. Conclusions These findings suggest that fascin overexpression plays a role in tumor growth and progression in ESCC and that cell death caused by its downregulation might be induced by cell adhesion loss. This indicates that targeting fascin pathway could be a novel therapeutic strategy for the human ESCC.

  19. Neoadjuvant targeted therapy in patients with renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    B. Ya. Alekseev

    2015-01-01

    Full Text Available Cytoreductive nephrectomy as an independent option in patients with metastatic renal cell carcinoma (mRCC cannot be considered as the only effective method, with rare exception, of a few patients with solitary metastases. Cytoreductive nephrectomy is now part of a multimodal approach encompassing surgical treatment and systemic drug therapy. Many retrospective and two prospective studies have demonstrated that it is expedient to perform cytoreductive nephrectomy. Immunotherapy should not be used as preoperatively in the era of cytokine therapy for mRCC due to that fact that it has no impact on primary tumor. In the current targeted therapy era, many investigators have concentrated attentionon the role of neoadjuvant targeted therapy for the treatment of patients with both localized and locally advanced mRCC. The potential benefits of neoadjuvant therapy for localized and locally advanced RCC include to make surgery easier and to increase the possibility of organsparing treatment, by decreasing the stage of primary tumor and the size of tumors. The possible potential advantages of neoadjuvant targeted therapy in patients with mRCC include prompt initiation of necessary systemic therapy; identification of patients with primary refractory tumors; and a preoperative reduction in the stage of primary tumor. Numerous retrospective and some prospective phase II studies have shown that neoadjuvant targeted therapy in patients with localized and locally advanced RCC is possible and tolerable and surgical treatment after neoadjuvant targeted therapy is safe and executable with a low incidence of complications. If neoadjuvant therapy is to be performed, it should be done within 2–4 months before surgery. Sorafenib and sunitinib are now most tested and suitable for neoadjuvant targeted therapy. Sorafenib is a more preferred drug due to its shorter half-life and accordingly to the possibility of discontinuing the drug immediately prior to

  20. Curcumin targets fibroblast–tumor cell interactions in oral squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Dudás, József, E-mail: jozsef.dudas@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Fullár, Alexandra, E-mail: fullarsz@gmail.com [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Üllői út 26, 1085 Budapest (Hungary); Romani, Angela, E-mail: angela.romani@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Pritz, Christian, E-mail: christian.pritz@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Kovalszky, Ilona, E-mail: koval@korb1.sote.hu [1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Üllői út 26, 1085 Budapest (Hungary); Hans Schartinger, Volker, E-mail: volker.schartinger@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Mathias Sprinzl, Georg, E-mail: georg.sprinzl@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Riechelmann, Herbert, E-mail: herbert.riechelmann@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria)

    2013-04-01

    Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of OSCC tumor cells. We hypothesized that Curcumin targets this dynamic mutual interaction between CAFs and tumor cells. Normal and 2 μM Curcumin-treated co-culture were performed for 4 days, followed by analysis of tumor cell invasivity, mRNA/protein expression of EMT-markers and mediators, activity measure of matrix metalloproteinase 9 (MMP-9), and western blot analysis of signal transduction in tumor cells and fibroblasts. In Curcumin-treated co-culture, in tumor cells, the levels of nuclear factor κB (NFκBα) and early response kinase (ERK)—decreased, in fibroblasts, integrin αv protein synthesis decreased compared to corresponding cells in normal co-culture. The signal modulatory changes induced by Curcumin caused decreased release of EMT-mediators in CAFs and reversal of EMT in tumor cells, which was associated with decreased invasion. These data confirm the palliative potential of Curcumin in clinical application. - Graphical abstract: Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of tumor cells. Curcumin targets this dynamic mutual interaction between CAFs and tumor cells by inhibiting the production of EMT mediators in CAFs and by modification of intracellular signaling in tumor cells. This causes less invasivity and reversal of EMT in tumor cells. Highlights: ► Curcumin targets tumor–fibroblast interaction in head and neck cancer. ► Curcumin suppresses mediators of epithelial–mesenchymal transition. ► Curcumin decreases the invasivity of tumor cells.

  1. Central nervous system myeloid cells as drug targets: current status and translational challenges.

    Science.gov (United States)

    Biber, Knut; Möller, Thomas; Boddeke, Erik; Prinz, Marco

    2016-02-01

    Myeloid cells of the central nervous system (CNS), which include parenchymal microglia, macrophages at CNS interfaces and monocytes recruited from the circulation during disease, are increasingly being recognized as targets for therapeutic intervention in neurological and psychiatric diseases. The origin of these cells in the immune system distinguishes them from ectodermal neurons and other glia and endows them with potential drug targets distinct from classical CNS target groups. However, despite the identification of several promising therapeutic approaches and molecular targets, no agents directly targeting these cells are currently available. Here, we assess strategies for targeting CNS myeloid cells and address key issues associated with their translation into the clinic.

  2. Stem Cell-Based Cell Carrier for Targeted Oncolytic Virotherapy: Translational Opportunity and Open Questions.

    Science.gov (United States)

    Kim, Janice; Hall, Robert R; Lesniak, Maciej S; Ahmed, Atique U

    2015-11-27

    Oncolytic virotherapy for cancer is an innovative therapeutic option where the ability of a virus to promote cell lysis is harnessed and reprogrammed to selectively destroy cancer cells. Such treatment modalities exhibited antitumor activity in preclinical and clinical settings and appear to be well tolerated when tested in clinical trials. However, the clinical success of oncolytic virotherapy has been significantly hampered due to the inability to target systematic metastasis. This is partly due to the inability of the therapeutic virus to survive in the patient circulation, in order to target tumors at distant sites. An early study from various laboratories demonstrated that cells infected with oncolytic virus can protect the therapeutic payload form the host immune system as well as function as factories for virus production and enhance the therapeutic efficacy of oncolytic virus. While a variety of cell lineages possessed potential as cell carriers, copious investigation has established stem cells as a very attractive cell carrier system in oncolytic virotherapy. The ideal cell carrier desire to be susceptible to viral infection as well as support viral infection, maintain immunosuppressive properties to shield the loaded viruses from the host immune system, and most importantly possess an intrinsic tumor homing ability to deliver loaded viruses directly to the site of the metastasis-all qualities stem cells exhibit. In this review, we summarize the recent work in the development of stem cell-based carrier for oncolytic virotherapy, discuss the advantages and disadvantages of a variety of cell carriers, especially focusing on why stem cells have emerged as the leading candidate, and finally propose a future direction for stem cell-based targeted oncolytic virotherapy that involves its establishment as a viable treatment option for cancer patients in the clinical setting.

  3. Oxymatrine liposome attenuates hepatic fibrosis via targeting hepatic stellate cells

    Institute of Scientific and Technical Information of China (English)

    Ning-Li Chai; Qiang Fu; Hui Shi; Chang-Hao Cai; Jun Wan; Shi-Ping Xu; Ben-Yan Wu

    2012-01-01

    AIM:To investigate the potential mechanism of ArgGly-Asp (RGD) peptide-labeled liposome loading oxymatrine (OM) therapy in CCl4-induced hepatic fibrosis in METHODS:We constructed a rat model of CCl4-induced hepatic fibrosis and treated the rats with different formulations of OM.To evaluate the antifibrotic effect of OM,we detected levels of alkaline phosphatase,hepatic histopathology (hematoxylin and eosin stain and Masson staining) and fibrosis-related gene expression of matrix metallopeptidase (MMP)-2,tissue inhibitor of metalloproteinase (TIMP)-1 as well as type Ⅰ procollagen via quantitative real-time polymerase chain reaction.To detect cell viability and apoptosis of hepatic stellate cells (HSCs),we performed 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay and flow cytometry.To reinforce the combination of oxymatrine with HSCs,we constructed fluorescein-isothiocyanate-conjugated Arg-Gly-Asp peptide-labeled liposomes loading OM,and its targeting of HSCs was examined by fluorescent microscopy.RESULTS:OM attenuated CCl4-induced hepatic fibrosis,as defined by reducing serum alkaline phosphatase (344.47 ± 27.52 U/L vs 550.69 ± 43.78 U/L,P < 0.05),attenuating liver injury and improving collagen deposits (2.36% ± 0.09% vs 7.70% ± 0.60%,P < 0.05) and downregulating fibrosis-related gene expression,that is,MMP-2,TIMP-1 and type Ⅰ procollagen (P < 0.05).OM inhibited cell viability and induced apoptosis of HSCs in vitro.RGD promoted OM targeting of HSCs and enhanced the therapeutic effect of OM in terms of serum alkaline phosphatase (272.51 ± 19.55 U/L vs 344.47 ± 27.52 U/L,P < 0.05),liver injury,collagen deposits (0.26% ± 0.09% vs 2.36% ± 0.09%,P < 0.05) and downregulating fibrosis-related gene expression,that is,MMP-2,TIMP-1 and type Ⅰ procollagen (P < 0.05).Moreover,in vitro assay demonstrated that RGD enhanced the effect of OM on HSC viability and apoptosis.CONCLUSION:OM attenuated hepatic fibrosis by

  4. RNA interference targeting raptor inhibits proliferation of gastric cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Wu, William Ka Kei; Lee, Chung Wa [Institute of Digestive Diseases, LKS Institute of Health Sciences and Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Cho, Chi Hin [Institute of Digestive Diseases, LKS Institute of Health Sciences and Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Chan, Francis Ka Leung [Institute of Digestive Diseases, LKS Institute of Health Sciences and Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Yu, Jun, E-mail: junyu@cuhk.edu.hk [Institute of Digestive Diseases, LKS Institute of Health Sciences and Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Sung, Joseph Jao Yiu, E-mail: joesung@cuhk.edu.hk [Institute of Digestive Diseases, LKS Institute of Health Sciences and Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China)

    2011-06-10

    Mammalian target of rapamycin complex 1 (mTORC1) is dysregulated in gastric cancer. The biologic function of mTORC1 in gastric carcinogenesis is unclear. Here, we demonstrate that disruption of mTORC1 function by RNA interference-mediated downregulation of raptor substantially inhibited gastric cancer cell proliferation through induction of G{sub 0}/G{sub 1}-phase cell cycle arrest. The anti-proliferative effect was accompanied by concomitant downregulation of activator protein-1 and upregulation of Smad2/3 transcriptional activities. In addition, the expression of cyclin D{sub 3} and p21{sup Waf1}, which stabilizes cyclin D/cdk4 complex for G{sub 1}-S transition, was reduced by raptor knockdown. In conclusion, disruption of mTORC1 inhibits gastric cancer cell proliferation through multiple pathways. This discovery may have an implication in the application of mTORC1-directed therapy for the treatment of gastric cancer.

  5. Rare earth fluorescent nanoparticles for specific cancer cell targeting

    Science.gov (United States)

    Stefanakis, Dimitrios; Ghanotakis, Demetrios F.

    2016-07-01

    Terbium layered hydroxide nanoparticles (Tb2(OH)5NO3) were synthesized by a one-pot coprecipitation method. The characterization of this preparation revealed highly oriented fluorescent nanoparticles. An attempt to improve the properties of Tb2(OH)5NO3 resulted in the preparation of two optimized nanoparticles. In particular, Tb2(OH)5NO3:Eu and Tb2(OH)5NO3-FA were prepared when Tb2(OH)5NO3 was doped with Europium and when the surface was modified with folic acid (FA), respectively. The size of the above nanoparticles was below 100 nm, and thus they have the potential to be used for biomedical applications. The interaction of nanoparticles with human cells was studied using confocal microscopy. This study revealed that only the nanoparticles modified with folic acid have the ability to be targeted to HeLa cells. This specific identification of cancer cells, in combination with the fluorescent properties of Tb2(OH)5NO3, could render these nanoparticles appropriate for biomedical applications.

  6. Facile Discovery of Cell-Surface Protein Targets of Cancer Cell Aptamers.

    Science.gov (United States)

    Bing, Tao; Shangguan, Dihua; Wang, Yinsheng

    2015-10-01

    Cancer biomarker discovery constitutes a frontier in cancer research. In recent years, cell-binding aptamers have become useful molecular probes for biomarker discovery. However, there are few successful examples, and the critical barrier resides in the identification of the cell-surface protein targets for the aptamers, where only a limited number of aptamer targets have been identified so far. Herein, we developed a universal SILAC-based quantitative proteomic method for target discovery of cell-binding aptamers. The method allowed for distinguishing specific aptamer-binding proteins from nonspecific proteins based on abundance ratios of proteins bound to aptamer-carrying bait and control bait. In addition, we employed fluorescently labeled aptamers for monitoring and optimizing the binding conditions. We were able to identify and validate selectin L and integrin α4 as the protein targets for two previously reported aptamers, Sgc-3b and Sgc-4e, respectively. This strategy should be generally applicable for the discovery of protein targets for other cell-binding aptamers, which will promote the applications of these aptamers.

  7. Selective cell targeting and lineage tracing of human induced pluripotent stem cells using recombinant avian retroviruses.

    Science.gov (United States)

    Hildebrand, Laura; Seemann, Petra; Kurtz, Andreas; Hecht, Jochen; Contzen, Jörg; Gossen, Manfred; Stachelscheid, Harald

    2015-12-01

    Human induced pluripotent stem cells (hiPSC) differentiate into multiple cell types. Selective cell targeting is often needed for analyzing gene function by overexpressing proteins in a distinct population of hiPSC-derived cell types and for monitoring cell fate in response to stimuli. However, to date, this has not been possible, as commonly used viruses enter the hiPSC via ubiquitously expressed receptors. Here, we report for the first time the application of a heterologous avian receptor, the tumor virus receptor A (TVA), to selectively transduce TVA(+) cells in a mixed cell population. Expression of the TVA surface receptor via genetic engineering renders cells susceptible for infection by avian leucosis virus (ALV). We generated hiPSC lines with this stably integrated, ectopic TVA receptor gene that expressed the receptor while retaining pluripotency. The undifferentiated hiPSC(TVA+) as well as their differentiating progeny could be infected by recombinant ALV (so-called RCAS virus) with high efficiency. Due to incomplete receptor blocking, even sequential infection of differentiating or undifferentiated TVA(+) cells was possible. In conclusion, the TVA/RCAS system provides an efficient and gentle gene transfer system for hiPSC and extends our possibilities for selective cell targeting and lineage tracing studies.

  8. Host Cell Factors as Antiviral Targets in Arenavirus Infection

    Directory of Open Access Journals (Sweden)

    Elsa B. Damonte

    2012-09-01

    Full Text Available Among the members of the Arenaviridae family, Lassa virus and Junin virus generate periodic annual outbreaks of severe human hemorrhagic fever (HF in endemic areas of West Africa and Argentina, respectively. Given the human health threat that arenaviruses represent and the lack of a specific and safe chemotherapy, the search for effective antiviral compounds is a continuous demanding effort. Since diverse host cell pathways and enzymes are used by RNA viruses to fulfill their replicative cycle, the targeting of a host process has turned an attractive antiviral approach in the last years for many unrelated virus types. This strategy has the additional benefit to reduce the serious challenge for therapy of RNA viruses to escape from drug effects through selection of resistant variants triggered by their high mutation rate. This article focuses on novel strategies to identify inhibitors for arenavirus therapy, analyzing the potential for antiviral developments of diverse host factors essential for virus infection.

  9. Host cell factors as antiviral targets in arenavirus infection.

    Science.gov (United States)

    Linero, Florencia N; Sepúlveda, Claudia S; Giovannoni, Federico; Castilla, Viviana; García, Cybele C; Scolaro, Luis A; Damonte, Elsa B

    2012-09-01

    Among the members of the Arenaviridae family, Lassa virus and Junin virus generate periodic annual outbreaks of severe human hemorrhagic fever (HF) in endemic areas of West Africa and Argentina, respectively. Given the human health threat that arenaviruses represent and the lack of a specific and safe chemotherapy, the search for effective antiviral compounds is a continuous demanding effort. Since diverse host cell pathways and enzymes are used by RNA viruses to fulfill their replicative cycle, the targeting of a host process has turned an attractive antiviral approach in the last years for many unrelated virus types. This strategy has the additional benefit to reduce the serious challenge for therapy of RNA viruses to escape from drug effects through selection of resistant variants triggered by their high mutation rate. This article focuses on novel strategies to identify inhibitors for arenavirus therapy, analyzing the potential for antiviral developments of diverse host factors essential for virus infection.

  10. Functional RNA delivery targeted to dendritic cells by synthetic nanoparticles.

    Science.gov (United States)

    McCullough, Kenneth C; Bassi, Isabelle; Démoulins, Thomas; Thomann-Harwood, Lisa J; Ruggli, Nicolas

    2012-09-01

    Dendritic cells (DCs) are essential to many aspects of immune defense development and regulation. They provide important targets for prophylactic and therapeutic delivery. While protein delivery has had considerable success, RNA delivery is still expanding. Delivering RNA molecules for RNAi has shown particular success and there are reports on successful delivery of mRNA. Central, therein, is the application of cationic entities. Following endocytosis of the delivery vehicle for the RNA, cationic entities should promote vesicular membrane perturbation, facilitating cytosolic release. The present review explains the diversity of DC function in immune response development and control. Promotion of delivered RNA cytosolic release is discussed, relating to immunoprophylactic and therapeutic potential, and DC endocytic machinery is reviewed, showing how DC endocytic pathways influence the handling of internalized material. The potential advantages for application of replicating RNA are presented and discussed, in consideration of their value and development in the near future.

  11. Engineering targeted chromosomal amplifications in human breast epithelial cells.

    Science.gov (United States)

    Springer, Simeon; Yi, Kyung H; Park, Jeenah; Rajpurohit, Anandita; Price, Amanda J; Lauring, Josh

    2015-07-01

    Chromosomal amplifications are among the most common genetic alterations found in human cancers. However, experimental systems to study the processes that lead to specific, recurrent amplification events in human cancers are lacking. Moreover, some common amplifications, such as that at 8p11-12 in breast cancer, harbor multiple driver oncogenes, which are poorly modeled by conventional overexpression approaches. We sought to develop an experimental system to model recurrent chromosomal amplification events in human cell lines. Our strategy is to use homologous-recombination-mediated gene targeting to deliver a dominantly selectable, amplifiable marker to a specified chromosomal location. We used adeno-associated virus vectors to target human MCF-7 breast cancer cells at the ZNF703 locus, in the recurrent 8p11-12 amplicon, using the E. coli inosine monophosphate dehydrogenase (IMPDH) enzyme as a marker. We applied selective pressure using IMPDH inhibitors. Surviving clones were found to have increased copy number of ZNF703 (average 2.5-fold increase) by droplet digital PCR and FISH. Genome-wide array comparative genomic hybridization confirmed that amplifications had occurred on the short arm of chromosome 8, without changes on 8q or other chromosomes. Patterns of amplification were variable and similar to those seen in primary human breast cancers, including "sawtooth" patterns, distal copy number loss, and large continuous regions of copy number gain. This system will allow study of the cis- and trans-acting factors that are permissive for chromosomal amplification and provide a model to analyze oncogene cooperativity in amplifications harboring multiple candidate driver genes.

  12. Active targeting of tumor cells using light emitting bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Sung Min; Min, Jung Joon; Hong, Yeong Jin; Kim, Hyun Ju; Le, Uuenchi N.; Rhee, Joon Haeng; Song, Ho Chun; Heo, Young Jun; Bom, Hee Seung; Choy, Hyon E [School of Medicine, Chonnam National University, Gwangju (Korea, Republic of)

    2004-07-01

    The presence of bacteria and viruses in human tumors has been recognized for more than 50 years. Today, with the discovery of bacterial strains that specifically target tumors, and aided by genomic sequencing and genetic engineering, there is new interest in the use of bacteria as tumor vectors. Here, we show that bacteria injected intravenously into live animals entered and replicated in solid tumors and metastases using the novel imaging technology of biophotonics. Bioluminescence operon (LuxCDABE) or fluorescence protein, GFP) has been cloned into pUC19 plasmid to engineer pUC19lux or pUC19gfp. Engineered plasmid was transformed into different kinds of wild type (MG1655) or mutant E. coli (DH5, ppGpp, fnr, purE, crpA, flagella, etc.) strains to construct light emitting bacteria. Xenograft tumor model has been established using CT26 colon cancer cell line. Light emitting bacteria was injected via tail vein into tumor bearing mouse. In vivo bioluminescence imaging has been done after 20 min to 14 days of bacterial injection. We observed localization of tumors by light-emitting E. coli in tumor (CT-26) bearing mice. We confirmed the presence of light-emitting bacteria under the fluorescence microscope with E. coli expressing GFP. Althoug varying mutants strain with deficient invading function has been found in tumor tissues, mutant strains of movement (flagella) couldn't show any light signal from the tumor tissue under the cooled CCD camera, indicating bacteria may actively target the tumor cells. Based on their 'tumor-finding' nature, bacteria may be designed to carry multiple genes or drugs for detection and treatment of cancer, such as prodrug-converting enzymes, toxins, angiogenesis inhibitors and cytokines.

  13. RNA interference targets arbovirus replication in Culicoides cells.

    Science.gov (United States)

    Schnettler, Esther; Ratinier, Maxime; Watson, Mick; Shaw, Andrew E; McFarlane, Melanie; Varela, Mariana; Elliott, Richard M; Palmarini, Massimo; Kohl, Alain

    2013-03-01

    Arboviruses are transmitted to vertebrate hosts by biting arthropod vectors such as mosquitoes, ticks, and midges. These viruses replicate in both arthropods and vertebrates and are thus exposed to different antiviral responses in these organisms. RNA interference (RNAi) is a sequence-specific RNA degradation mechanism that has been shown to play a major role in the antiviral response against arboviruses in mosquitoes. Culicoides midges are important vectors of arboviruses, known to transmit pathogens of humans and livestock such as bluetongue virus (BTV) (Reoviridae), Oropouche virus (Bunyaviridae), and likely the recently discovered Schmallenberg virus (Bunyaviridae). In this study, we investigated whether Culicoides cells possess an antiviral RNAi response and whether this is effective against arboviruses, including those with double-stranded RNA (dsRNA) genomes, such as BTV. Using reporter gene-based assays, we established the presence of a functional RNAi response in Culicoides sonorensis-derived KC cells which is effective in inhibiting BTV infection. Sequencing of small RNAs from KC and Aedes aegypti-derived Aag2 cells infected with BTV or the unrelated Schmallenberg virus resulted in the production of virus-derived small interfering RNAs (viRNAs) of 21 nucleotides, similar to the viRNAs produced during arbovirus infections of mosquitoes. In addition, viRNA profiles strongly suggest that the BTV dsRNA genome is accessible to a Dicer-type nuclease. Thus, we show for the first time that midge cells target arbovirus replication by mounting an antiviral RNAi response mainly resembling that of other insect vectors of arboviruses.

  14. Cornering metastases: therapeutic targeting of circulating tumor cells and stem cells.

    Directory of Open Access Journals (Sweden)

    Bishoy eFaltas

    2012-07-01

    Full Text Available The last decade has witnessed an evolution of our understanding of the biology of the metastatic cascade. Recent insights into the metastatic process show that it is complex, dynamic and multi-directional. This process starts at a very early stage in the natural history of solid tumor growth leading to early development of metastases that grow in parallel with the primary tumor. The role of stem cells in perpetuating cancer metastases is increasingly becoming more evident. At the same time, there is a growing recognition of the crucial role circulating tumor cells (CTCs play in the development of metastases. These insights have laid the biological foundations for therapeutic targeting of CTCs, a promising area of research that aims to reduce cancer morbidity and mortality by preventing the development of metastases at a very early stage. The hematogenous transport phase of the metastatic cascade provides critical access to CTCs for therapeutic targeting aiming to interrupt the metastatic process. Recent advances in the fields of nanotechnology and micro-fluidics have led to the development of several devices for in-vivo targeting of CTC during transit in the circulation. Selectin-coated tubes that target cell adhesion molecules, immuno-magnetic separators and in-vivo photoacoustic flow cytometers are currently being developed for this purpose. On the pharmacological front, several pharmacological and immunological agents targeting cancer stem cells are currently being developed. Such agents may ultimately prove to be effective against circulating tumor stem cells (CTSCs. Although still in its infancy, therapeutic targeting of CTCs and CTSCs offers an unprecedented opportunity to prevent the development of metastasis and potentially alter the natural history of cancer. By rendering cancer a local disease, these approaches could lead to major reductions in metastasis-related morbidity and mortality.

  15. Cell Membrane-Cloaked Nanoparticles for Targeted Therapeutics

    Science.gov (United States)

    Luk, Brian Tsengchi

    interactions between membranes and synthetic nanoparticles, and how the membrane coating technique faithfully translates the complexities of natural cellular membranes to the nanoscale. The following three sections explore potential therapeutic applications of membrane-coated nanoparticles for targeted drug delivery, biodetoxification, and immunomodulation. Ultimately, cell membrane-cloaked nanoparticles have the potential to significantly change the landscape of nanomedicine. The novel applications presented in this thesis are just a few of many examples currently being researched, with countless more avenues waiting to be explored.

  16. Free Extracellular miRNA Functionally Targets Cells by Transfecting Exosomes from Their Companion Cells.

    Directory of Open Access Journals (Sweden)

    Krzysztof Bryniarski

    Full Text Available Lymph node and spleen cells of mice doubly immunized by epicutaneous and intravenous hapten application produce a suppressive component that inhibits the action of the effector T cells that mediate contact sensitivity reactions. We recently re-investigated this phenomenon in an immunological system. CD8+ T lymphocyte-derived exosomes transferred suppressive miR-150 to the effector T cells antigen-specifically due to exosome surface coat of antibody light chains made by B1a lymphocytes. Extracellular RNA (exRNA is protected from plasma RNases by carriage in exosomes or by chaperones. Exosome transfer of functional RNA to target cells is well described, whereas the mechanism of transfer of exRNA free of exosomes remains unclear. In the current study we describe extracellular miR-150, extracted from exosomes, yet still able to mediate antigen-specific suppression. We have determined that this was due to miR-150 association with antibody-coated exosomes produced by B1a cell companions of the effector T cells, which resulted in antigen-specific suppression of their function. Thus functional cell targeting by free exRNA can proceed by transfecting companion cell exosomes that then transfer RNA cargo to the acceptor cells. This contrasts with the classical view on release of RNA-containing exosomes from the multivesicular bodies for subsequent intercellular targeting. This new alternate pathway for transfer of exRNA between cells has distinct biological and immunological significance, and since most human blood exRNA is not in exosomes may be relevant to evaluation and treatment of diseases.

  17. Osteosarcoma: Cells-of-Origin, Cancer Stem Cells, and Targeted Therapies

    Directory of Open Access Journals (Sweden)

    Ander Abarrategi

    2016-01-01

    Full Text Available Osteosarcoma (OS is the most common type of primary solid tumor that develops in bone. Although standard chemotherapy has significantly improved long-term survival over the past few decades, the outcome for those patients with metastatic or recurrent OS remains dismally poor and, therefore, novel agents and treatment regimens are urgently required. A hypothesis to explain the resistance of OS to chemotherapy is the existence of drug resistant CSCs with progenitor properties that are responsible of tumor relapses and metastasis. These subpopulations of CSCs commonly emerge during tumor evolution from the cell-of-origin, which are the normal cells that acquire the first cancer-promoting mutations to initiate tumor formation. In OS, several cell types along the osteogenic lineage have been proposed as cell-of-origin. Both the cell-of-origin and their derived CSC subpopulations are highly influenced by environmental and epigenetic factors and, therefore, targeting the OS-CSC environment and niche is the rationale for many recently postulated therapies. Likewise, some strategies for targeting CSC-associated signaling pathways have already been tested in both preclinical and clinical settings. This review recapitulates current OS cell-of-origin models, the properties of the OS-CSC and its niche, and potential new therapies able to target OS-CSCs.

  18. Glioblastoma: Molecular Pathways, Stem Cells and Therapeutic Targets

    Energy Technology Data Exchange (ETDEWEB)

    Jhanwar-Uniyal, Meena, E-mail: meena_jhanwar@nymc.edu; Labagnara, Michael; Friedman, Marissa; Kwasnicki, Amanda; Murali, Raj [Department of Neurosurgery, New York Medical College, Valhalla, NY 10595 (United States)

    2015-03-25

    Glioblastoma (GBM), a WHO-defined Grade IV astrocytoma, is the most common and aggressive CNS malignancy. Despite current treatment modalities, the survival time remains dismal. The main cause of mortality in patients with this disease is reoccurrence of the malignancy, which is attributed to treatment-resistant cancer stem cells within and surrounding the primary tumor. Inclusion of novel therapies, such as immuno- and DNA-based therapy, may provide better means of treating GBM. Furthermore, manipulation of recently discovered non-coding microRNAs, some of which regulate tumor growth through the development and maintenance of GBM stem cells, could provide new prospective therapies. Studies conducted by The Cancer Genome Atlas (TCGA) also demonstrate the role of molecular pathways, specifically the activated PI3K/AKT/mTOR pathway, in GBM tumorigenesis. Inhibition of the aforementioned pathway may provide a more direct and targeted method to GBM treatment. The combination of these treatment modalities may provide an innovative therapeutic approach for the management of GBM.

  19. A new target for the HYPOM polarimeter with plane LH{sub 2} cells

    Energy Technology Data Exchange (ETDEWEB)

    Golovanov, L.B.; Borzounov, Yu.; Piskunov, N.M.; Tsvinev, A.P.; Ball, J.; Sans, J.L.; Tomasi-Gustafsson, E. E-mail: etomasi@cea.fr

    1999-06-01

    We present a new liquid hydrogen target working as a secondary target for an extended polarimeter. The specificity of this target is that the inner cell has a parallelepipedic shape. The dimensions along the beam and along the focal plane are maximized, for a small vertical extension, using a much smaller volume of liquid hydrogen, as compared to standard cylindrical cells.

  20. Targeting Cell Surface Proteins in Molecular Photoacoustic Imaging to Detect Ovarian Cancer Early

    Science.gov (United States)

    2013-07-01

    10-1-0422 TITLE: Targeting Cell Surface Proteins in Molecular Photoacoustic Imaging to Detect Ovarian Cancer Early PRINCIPAL...DATES COVERED 1 July 2010 - 30 June 2013 4. TITLE AND SUBTITLE Targeting Cell Surface Proteins in Molecular 5a. CONTRACT NUMBER Photoacoustic ...upon request). Aim 2) Prioritize ovarian cancer-associated surface proteins for their utility as molecular photoacoustic imaging targets and

  1. A smart multifunctional drug delivery nanoplatform for targeting cancer cells

    Science.gov (United States)

    Hoop, M.; Mushtaq, F.; Hurter, C.; Chen, X.-Z.; Nelson, B. J.; Pané, S.

    2016-06-01

    most tumors. Approximately a 2.5 times higher drug release from Ni nanotubes at pH = 6 is achieved compared to that at pH = 7.4. The outside of the Ni tube is coated with gold. A fluorescein isothiocyanate (FITC) labeled thiol-ssDNA, a biological marker, was conjugated on its surface by thiol-gold click chemistry, which enables traceability. The Ni nanotube allows the propulsion of the device by means of external magnetic fields. As the proposed nanoarchitecture integrates different functional building blocks, our drug delivery nanoplatform can be employed for carrying molecular drug conjugates and for performing targeted combinatorial therapies, which can provide an alternative and supplementary solution to current drug delivery technologies. Electronic supplementary information (ESI) available: Fig. S1 drug release control experiment; Fig. S2 cell viability assay; video - magnetic manipulation. See DOI: 10.1039/c6nr02228f

  2. Clinical immunotherapy of B-cell malignancy using CD19-targeted CAR T-cells.

    Science.gov (United States)

    Maher, John

    2014-02-01

    The CD19 molecule is ubiquitously expressed throughout all stages of B-cell differentiation, but is not found on haemopoietic stem cells. Since most B-cell leukaemias and lymphomas retain CD19 expression, it represents an excellent target for immunotherapy of these malignant disorders. Over the past 10 years, compelling pre-clinical evidence has accrued to indicate that expression of a CD19-targeted chimeric antigen receptor (CAR) in peripheral blood T-cells exerts therapeutic efficacy in diverse models of B-cell malignancy. Building on this, clinical studies are ongoing in several centres in which autologous CD19-specific CAR T-cells are undergoing evaluation in patients with acute and chronic B-cell leukaemia and refractory lymphoma. Early data have generated considerable excitement, providing grounds to speculate that CAR-based immunotherapy will radically alter existing management paradigms in B-cell malignancy. The focus of this mini-review is to evaluate these emerging clinical data and to speculate on clinical prospects for this new therapeutic modality.

  3. Targeting miR-155 suppresses proliferation and induces apoptosis of HL-60 cells by targeting Slug/PUMA signal.

    Science.gov (United States)

    Liang, Hui; Dong, Ziyan; Liu, Jiang-Feng; Chuang, Wei; Gao, Li-Zhen; Ren, Yu-Guo

    2016-10-27

    Recent studies have shown that high miR-155 expression was associated with poor prognosis in patients with acute myelogeneous leukemia (AML). Furthermore, targeting miR-155 results in monocytic differentiation and apoptosis. However, the exact role and mechanisms of miR-155 in human AML remains speculative. HL-60 cells were treated with anti-miR-155 for 72 h. Cell growth and apoptosis in vitro were detected by MTT, BrdU proliferation, colony formation and flow cytometry assay. The effect of anti-miR-155 on growth of HL-60 cells was also evaluated in a leukemia mouse model. Slug cDNA and PUMA siRNA trannsfection was used to assess the signal pathway. Different protein expression was detected by western blot assay and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assay. The results shown that targeting miR-155 resulted in a 24-fold decrease of miR-155 expression compared to negative control in the HL-60 cells. Targeting miR-155 significantly downregulated Slug and upregulated PUMA expression, and decreased HL-60 cell growth by 70% , impaired colony formation by approximately 60%, and increased HL-60 cell apoptosis by 45%. Targeting PUMA reversed miR-155 sliencing-induced proliferation and apoptosis of HL-60 cells. Restoration of Slug decreased PUMA expression. In murine engraftment models of HL-60 cells, we showed that targeting miR-155 was able to reduce tumor growth. This was accompanied with decreased Slug expression and increased PUMA expression in these tumors. Collectively, our findings strongly suggest targeting miR-155 exhibited in vivo and in vitro antileukemic activities in AML through a novel mechanism resulting in inhibition of Slug expression and increase of PUMA expression.

  4. Bypassing Protein Corona Issue on Active Targeting: Zwitterionic Coatings Dictate Specific Interactions of Targeting Moieties and Cell Receptors.

    Science.gov (United States)

    Safavi-Sohi, Reihaneh; Maghari, Shokoofeh; Raoufi, Mohammad; Jalali, Seyed Amir; Hajipour, Mohammad J; Ghassempour, Alireza; Mahmoudi, Morteza

    2016-09-07

    Surface functionalization strategies for targeting nanoparticles (NP) to specific organs, cells, or organelles, is the foundation for new applications of nanomedicine to drug delivery and biomedical imaging. Interaction of NPs with biological media leads to the formation of a biomolecular layer at the surface of NPs so-called as "protein corona". This corona layer can shield active molecules at the surface of NPs and cause mistargeting or unintended scavenging by the liver, kidney, or spleen. To overcome this corona issue, we have designed biotin-cysteine conjugated silica NPs (biotin was employed as a targeting molecule and cysteine was used as a zwitterionic ligand) to inhibit corona-induced mistargeting and thus significantly enhance the active targeting capability of NPs in complex biological media. To probe the targeting yield of our engineered NPs, we employed both modified silicon wafer substrates with streptavidin (i.e., biotin receptor) to simulate a target and a cell-based model platform using tumor cell lines that overexpress biotin receptors. In both cases, after incubation with human plasma (thus forming a protein corona), cellular uptake/substrate attachment of the targeted NPs with zwitterionic coatings were significantly higher than the same NPs without zwitterionic coating. Our results demonstrated that NPs with a zwitterionic surface can considerably facilitate targeting yield of NPs and provide a promising new type of nanocarriers in biological applications.

  5. Rationally designed BCL6 inhibitors target activated B cell diffuse large B cell lymphoma.

    Science.gov (United States)

    Cardenas, Mariano G; Yu, Wenbo; Beguelin, Wendy; Teater, Matthew R; Geng, Huimin; Goldstein, Rebecca L; Oswald, Erin; Hatzi, Katerina; Yang, Shao-Ning; Cohen, Joanna; Shaknovich, Rita; Vanommeslaeghe, Kenno; Cheng, Huimin; Liang, Dongdong; Cho, Hyo Je; Abbott, Joshua; Tam, Wayne; Du, Wei; Leonard, John P; Elemento, Olivier; Cerchietti, Leandro; Cierpicki, Tomasz; Xue, Fengtian; MacKerell, Alexander D; Melnick, Ari M

    2016-09-01

    Diffuse large B cell lymphomas (DLBCLs) arise from proliferating B cells transiting different stages of the germinal center reaction. In activated B cell DLBCLs (ABC-DLBCLs), a class of DLBCLs that respond poorly to current therapies, chromosomal translocations and amplification lead to constitutive expression of the B cell lymphoma 6 (BCL6) oncogene. The role of BCL6 in maintaining these lymphomas has not been investigated. Here, we designed small-molecule inhibitors that display higher affinity for BCL6 than its endogenous corepressor ligands to evaluate their therapeutic efficacy for targeting ABC-DLBCL. We used an in silico drug design functional-group mapping approach called SILCS to create a specific BCL6 inhibitor called FX1 that has 10-fold greater potency than endogenous corepressors and binds an essential region of the BCL6 lateral groove. FX1 disrupted formation of the BCL6 repression complex, reactivated BCL6 target genes, and mimicked the phenotype of mice engineered to express BCL6 with corepressor binding site mutations. Low doses of FX1 induced regression of established tumors in mice bearing DLBCL xenografts. Furthermore, FX1 suppressed ABC-DLBCL cells in vitro and in vivo, as well as primary human ABC-DLBCL specimens ex vivo. These findings indicate that ABC-DLBCL is a BCL6-dependent disease that can be targeted by rationally designed inhibitors that exceed the binding affinity of natural BCL6 ligands.

  6. A model of calcium-mediated coupling between membrane activity and clock gene expression in neurons of the suprachiasmatic nucleus

    CERN Document Server

    Casado, J M

    2015-01-01

    Rhythms in electrical activity in the membrane of cells in the suprachiasmatic nucleus (SCN) are crucial for the function of the circadian timing system, which is characterized by the expression of the so-called clock genes. Intracellular Ca$^{2+}$ ions seem to connect, at least in part, the electrical activity of SCN neurons with the expression of clock genes. In this paper, we introduce a simple mathematical model describing the linking of membrane activity to the transcription of one gene by means of a feedback mechanism based on the dynamics of intracellular calcium ions.

  7. Mammalian target of rapamycin activity is required for expansion of CD34(+) hematopoietic progenitor cells

    NARCIS (Netherlands)

    Geest, Christian R.; Zwartkruis, Fried J.; Vellenga, Edo; Coffer, Paul J.; Buitenhuis, Miranda

    2009-01-01

    Background The mammalian target of rapamycin is a conserved protein kinase known to regulate protein synthesis, cell size and proliferation. Aberrant regulation of mammalian target of rapamycin activity has been observed in hematopoietic malignancies, including acute leukemias and myelodysplastic sy

  8. Mammalian target of rapamycin activity is required for expansion of CD34+ hematopoietic progenitor cells

    NARCIS (Netherlands)

    Geest, C.R.; Zwartkruis, G.J.T.; Vellenga, E.; Coffer, P.J.; Buitenhuis, M.

    2009-01-01

    Background The mammalian target of rapamycin is a conserved protein kinase known to regulate protein synthesis, cell size and proliferation. Aberrant regulation of mammalian target of rapamycin activity has been observed in hematopoietic malignancies, including acute leukemias and myelodysplastic sy

  9. Targeting breast cancer stem cells with HER2-specific antibodies and natural killer cells.

    Science.gov (United States)

    Diessner, Joachim; Bruttel, Valentin; Becker, Kathrin; Pawlik, Miriam; Stein, Roland; Häusler, Sebastian; Dietl, Johannes; Wischhusen, Jörg; Hönig, Arnd

    2013-01-01

    Breast cancer is the most common cancer among women worldwide. Every year, nearly 1.4 million new cases of breast cancer are diagnosed, and about 450.000 women die of the disease. Approximately 15-25% of breast cancer cases exhibit increased quantities of the trans-membrane receptor tyrosine kinase human epidermal growth factor receptor 2 (HER2) on the tumor cell surface. Previous studies showed that blockade of this HER2 proto-oncogene with the antibody trastuzumab substantially improved the overall survival of patients with this aggressive type of breast cancer. Recruitment of natural killer (NK) cells and subsequent induction of antibody-dependent cell-mediated cytotoxicity (ADCC) contributed to this beneficial effect. We hypothesized that antibody binding to HER2-positive breast cancer cells and thus ADCC might be further improved by synergistically applying two different HER2-specific antibodies, trastuzumab and pertuzumab. We found that tumor cell killing via ADCC was increased when the combination of trastuzumab, pertuzumab, and NK cells was applied to HER2-positive breast cancer cells, as compared to the extent of ADCC induced by a single antibody. Furthermore, a subset of CD44(high)CD24(low)HER2(low) cells, which possessed characteristics of cancer stem cells, could be targeted more efficiently by the combination of two HER2-specific antibodies compared to the efficiency of one antibody. These in vitro results demonstrated the immunotherapeutic benefit achieved by the combined application of trastuzumab and pertuzumab. These findings are consistent with the positive results of the clinical studies, CLEOPATRA and NEOSPHERE, conducted with patients that had HER2-positive breast cancer. Compared to a single antibody treatment, the combined application of trastuzumab and pertuzumab showed a stronger ADCC effect and improved the targeting of breast cancer stem cells.

  10. RNA Interference Targeting Leptin Gene Effect on Hepatic Stellate Cells

    Institute of Scientific and Technical Information of China (English)

    XUE Xiulan; LIN Jusheng; SONG Yuhu; SUN Xuemei; ZHOU Hejun

    2005-01-01

    To construct the specific siRNA expression vectors and investigate their effect on leptin and collagen I in HSC, which provide a new approach to the prevent and treat hepatic fibrosis. The five siRNAs against leptin gene were transcript synthesized intracellularly by expression templates of plasmid vector psiRNA-hH1neo. The recombinant leptin siRNA plasmid vectors could express in eukaryocyte , and then to evaluate them by using enzyme cutting and sequencing. The recombinant plasmids were transfected into HSCs using Lipofectamine methods respectively. The cells were selected after growing in DMEM containing 300 μg/mL G418 for about 4 weeks. Gene expression of leptin and collagen I were showed by Western blot analysis and reverse transcription polymerase chain reaction (RT-PCR). Identification by enzyme cutting and sequencing showed that the leptin siRNA expression vectors were constructed successfully, and leptin siRNA could inhibit the leptin and collagen I gene expression effectively. It was concluded that RNA interference-mediated silencing of leptin gene diminished leptin and collagen I gene expression in HSCs. Furthermore, attenuated the extracellular matrix over-deposition at the same time. Leptin gene is ideal targets of gene therapy for liver fibrosis.

  11. Targeted Application of Human Genetic Variation Can Improve Red Blood Cell Production from Stem Cells.

    Science.gov (United States)

    Giani, Felix C; Fiorini, Claudia; Wakabayashi, Aoi; Ludwig, Leif S; Salem, Rany M; Jobaliya, Chintan D; Regan, Stephanie N; Ulirsch, Jacob C; Liang, Ge; Steinberg-Shemer, Orna; Guo, Michael H; Esko, Tõnu; Tong, Wei; Brugnara, Carlo; Hirschhorn, Joel N; Weiss, Mitchell J; Zon, Leonard I; Chou, Stella T; French, Deborah L; Musunuru, Kiran; Sankaran, Vijay G

    2016-01-07

    Multipotent and pluripotent stem cells are potential sources for cell and tissue replacement therapies. For example, stem cell-derived red blood cells (RBCs) are a potential alternative to donated blood, but yield and quality remain a challenge. Here, we show that application of insight from human population genetic studies can enhance RBC production from stem cells. The SH2B3 gene encodes a negative regulator of cytokine signaling and naturally occurring loss-of-function variants in this gene increase RBC counts in vivo. Targeted suppression of SH2B3 in primary human hematopoietic stem and progenitor cells enhanced the maturation and overall yield of in-vitro-derived RBCs. Moreover, inactivation of SH2B3 by CRISPR/Cas9 genome editing in human pluripotent stem cells allowed enhanced erythroid cell expansion with preserved differentiation. Our findings therefore highlight the potential for combining human genome variation studies with genome editing approaches to improve cell and tissue production for regenerative medicine.

  12. Targeted and non-targeted effects in cell wall polysaccharides from transgenetically modified potato tubers

    NARCIS (Netherlands)

    Huang, J.H.

    2016-01-01

    The plant cell wall is a chemically complex network composed mainly of polysaccharides. Cell wall polysaccharides surround and protect plant cells and are responsible for the stability and rigidity of plant tissue. Pectin is a major component of primary cell wall and the middle lamella of plants. Ho

  13. Identification of ligand-target pairs from combined libraries of small molecules and unpurified protein targets in cell lysates.

    Science.gov (United States)

    McGregor, Lynn M; Jain, Tara; Liu, David R

    2014-02-26

    We describe the development and validation of interaction determination using unpurified proteins (IDUP), a method that selectively amplifies DNA sequences identifying ligand+target pairs from a mixture of DNA-linked small molecules and unpurified protein targets in cell lysates. By operating in cell lysates, IDUP preserves native post-translational modifications and interactions with endogenous binding partners, thereby enabling the study of difficult-to-purify targets and increasing the potential biological relevance of detected interactions compared with methods that require purified proteins. In IDUP, target proteins are associated with DNA oligonucleotide tags either non-covalently using a DNA-linked antibody or covalently using a SNAP-tag. Ligand-target binding promotes hybridization of a self-priming hairpin that is extended by a DNA polymerase to create a DNA strand that contains sequences identifying both the target and its ligand. These sequences encoding ligand+target pairs are selectively amplified by PCR and revealed by high-throughput DNA sequencing. IDUP can respond to the effect of affinity-modulating adaptor proteins in cell lysates that would be absent in ligand screening or selection methods using a purified protein target. This capability was exemplified by the 100-fold amplification of DNA sequences encoding FRB+rapamycin or FKBP+rapamycin in samples overexpressing both FRB and FKBP (FRB·rapamycin+FKBP, Kd ≈ 100 fM; FKBP·rapamycin+FRB, Kd = 12 nM). In contrast, these sequences were amplified 10-fold less efficiently in samples overexpressing either FRB or FKBP alone (rapamycin+FKBP, Kd ≈ 0.2 nM; rapamcyin+FRB, Kd = 26 μM). Finally, IDUP was used to process a model library of DNA-linked small molecules and a model library of cell lysates expressing SNAP-target fusions combined in a single sample. In this library×library experiment, IDUP resulted in enrichment of sequences corresponding to five known ligand+target pairs ranging in binding

  14. An innovative pre-targeting strategy for tumor cell specific imaging and therapy

    Science.gov (United States)

    Qin, Si-Yong; Peng, Meng-Yun; Rong, Lei; Jia, Hui-Zhen; Chen, Si; Cheng, Si-Xue; Feng, Jun; Zhang, Xian-Zheng

    2015-08-01

    A programmed pre-targeting system for tumor cell imaging and targeting therapy was established based on the ``biotin-avidin'' interaction. In this programmed functional system, transferrin-biotin can be actively captured by tumor cells with the overexpression of transferrin receptors, thus achieving the pre-targeting modality. Depending upon avidin-biotin recognition, the attachment of multivalent FITC-avidin to biotinylated tumor cells not only offered the rapid fluorescence labelling, but also endowed the pre-targeted cells with targeting sites for the specifically designed biotinylated peptide nano-drug. Owing to the successful pre-targeting, tumorous HepG2 and HeLa cells were effectively distinguished from the normal 3T3 cells via fluorescence imaging. In addition, the self-assembled peptide nano-drug resulted in enhanced cell apoptosis in the observed HepG2 cells. The tumor cell specific pre-targeting strategy is applicable for a variety of different imaging and therapeutic agents for tumor treatments.A programmed pre-targeting system for tumor cell imaging and targeting therapy was established based on the ``biotin-avidin'' interaction. In this programmed functional system, transferrin-biotin can be actively captured by tumor cells with the overexpression of transferrin receptors, thus achieving the pre-targeting modality. Depending upon avidin-biotin recognition, the attachment of multivalent FITC-avidin to biotinylated tumor cells not only offered the rapid fluorescence labelling, but also endowed the pre-targeted cells with targeting sites for the specifically designed biotinylated peptide nano-drug. Owing to the successful pre-targeting, tumorous HepG2 and HeLa cells were effectively distinguished from the normal 3T3 cells via fluorescence imaging. In addition, the self-assembled peptide nano-drug resulted in enhanced cell apoptosis in the observed HepG2 cells. The tumor cell specific pre-targeting strategy is applicable for a variety of different imaging

  15. Antibody-targeting of steady state dendritic cells induces tolerance mediated by regulatory T cells

    Directory of Open Access Journals (Sweden)

    Karsten eMahnke

    2016-02-01

    Full Text Available Dendritic cells (DCs are often defined as pivotal inducers of immunity, but these proinflammatory properties only develop after stimulation or ex vivo manipulation of DCs. Under non-inflammatory conditions in vivo, DCs are embedded into a tissue environment and encounter a plethora of self-antigens derived from apoptotic material. This material is transported to secondary lymphoid organs. As DCs maintain their non-activated phenotype in a sterile tissue environment, interaction with T cells will induce rather regulatory T cells (Treg than effector T cells. Thus, DCs are not only inducers of immunity but are also critical for maintenance of peripheral tolerance. Therapeutical intervention for the induction of long lasting tolerance in several autoimmune conditions may therefore be possible by manipulating DC activation and/or targeting of DCs in their natural tissue environment.

  16. Inhibition of notch signaling in glioblastoma targets cancer stem cells via an endothelial cell intermediate.

    Science.gov (United States)

    Hovinga, Koos E; Shimizu, Fumiko; Wang, Rong; Panagiotakos, Georgia; Van Der Heijden, Maartje; Moayedpardazi, Hamideh; Correia, Ana Sofia; Soulet, Denis; Major, Tamara; Menon, Jayanthi; Tabar, Viviane

    2010-06-01

    Glioblastoma multiforme (GBM) is a highly heterogeneous malignant tumor. Recent data suggests the presence of a hierarchical organization within the GBM cell population that involves cancer cells with stem-like behavior, capable of repopulating the tumor and contributing to its resistance to therapy. Tumor stem cells are thought to reside within a vascular niche that provides structural and functional support. However, most GBM studies involve isolated tumor cells grown under various culture conditions. Here, we use a novel three-dimensional organotypic "explant" system of surgical GBM specimens that preserves cytoarchitecture and tumor stroma along with tumor cells. Notch inhibition in explants results in decreased proliferation and self-renewal of tumor cells but is also associated with a decrease in endothelial cells. When endothelial cells are selectively eliminated from the explants via a toxin conjugate, we also observed a decrease in self-renewal of tumor stem cells. These findings support a critical role for tumor endothelial cells in GBM stem cell maintenance, mediated at least in part by Notch signaling. The explant system further highlighted differences in the response to radiation between explants and isolated tumor neurospheres. Combination treatment with Notch blockade and radiation resulted in a substantial decrease in proliferation and in self-renewal in tumor explants while radiation alone was less effective. This data suggests that the Notch pathway plays a critical role in linking angiogenesis and cancer stem cell self-renewal and is thus a potential therapeutic target. Three-dimensional explant systems provide a novel approach for the study of tumor and microenvironment interactions.

  17. A Modular Probe Strategy for Drug Localization, Target Identification and Target Occupancy Measurement on Single Cell Level.

    Science.gov (United States)

    Rutkowska, Anna; Thomson, Douglas W; Vappiani, Johanna; Werner, Thilo; Mueller, Katrin M; Dittus, Lars; Krause, Jana; Muelbaier, Marcel; Bergamini, Giovanna; Bantscheff, Marcus

    2016-09-16

    Late stage failures of candidate drug molecules are frequently caused by off-target effects or inefficient target engagement in vivo. In order to address these fundamental challenges in drug discovery, we developed a modular probe strategy based on bioorthogonal chemistry that enables the attachment of multiple reporters to the same probe in cell extracts and live cells. In a systematic evaluation, we identified the inverse electron demand Diels-Alder reaction between trans-cyclooctene labeled probe molecules and tetrazine-tagged reporters to be the most efficient bioorthogonal reaction for this strategy. Bioorthogonal biotinylation of the probe allows the identification of drug targets in a chemoproteomics competition binding assay using quantitative mass spectrometry. Attachment of a fluorescent reporter enables monitoring of spatial localization of probes as well as drug-target colocalization studies. Finally, direct target occupancy of unlabeled drugs can be determined at single cell resolution by competitive binding with fluorescently labeled probe molecules. The feasibility of the modular probe strategy is demonstrated with noncovalent PARP inhibitors.

  18. Cell Membrane Capsules for Encapsulation of Chemotherapeutic and Cancer Cell Targeting in Vivo.

    Science.gov (United States)

    Peng, Li-Hua; Zhang, Yuan-Hong; Han, Li-Jie; Zhang, Chen-Zhen; Wu, Jia-He; Wang, Xia-Rong; Gao, Jian-Qing; Mao, Zheng-Wei

    2015-08-26

    Systemic administration of chemotherapeutic agents can cause indiscriminate drug distribution and severe toxicity. Until now, encapsulation and targeting of drugs have typically relied on synthetic vehicles, which cannot minimize the clearance by the renal system and may also increase the risk of chemical side effects. Cell membrane capsules (CMCs) provide a generic and far more natural approach to the challenges of drug encapsulation and delivery in vivo. Here aptamer AS1411, which can recognize and bind overexpressed nucleolin on a cancer cell membrane, was chemically conjugated onto CMCs. As a result, AS1411 modified CMCs showed enhanced ingestion in certain cancer cells in vitro and accumulation in mouse cancer xenografts in vivo. Chemotherapeutics and contrast agents with therapeutically significant concentrations can be packaged into CMCs by reversible permeating their plasma membranes. The systematic administration of cancer targeting CMCs loaded with doxorubicin hydrochloride can significantly inhibit tumor growth in mouse xenografts, with significantly reduced toxicity compared to free drug. These findings suggest that cancer targeting CMCs may have considerable benefits in drug delivery and cancer treatment.

  19. Display of GPI-anchored anti-EGFR nanobodies on extracellular vesicles promotes tumour cell targeting

    NARCIS (Netherlands)

    Kooijmans, Sander A A; Aleza, Clara Gómez; Roffler, Steve R; van Solinge, Wouter W; Vader, Pieter; Schiffelers, Raymond M

    2016-01-01

    BACKGROUND: Extracellular vesicles (EVs) are attractive candidate drug delivery systems due to their ability to functionally transport biological cargo to recipient cells. However, the apparent lack of target cell specificity of exogenously administered EVs limits their therapeutic applicability. In

  20. Single granule cells reliably discharge targets in the hippocampal CA3 network in vivo.

    Science.gov (United States)

    Henze, Darrell A; Wittner, Lucia; Buzsáki, György

    2002-08-01

    Processing of neuronal information depends on interactions between the anatomical connectivity and cellular properties of single cells. We examined how these computational building blocks work together in the intact rat hippocampus. Single spikes in dentate granule cells, controlled intracellularly, generally failed to discharge either interneurons or CA3 pyramidal cells. In contrast, trains of spikes effectively discharged both CA3 cell types. Increasing the discharge rate of the granule cell increased the discharge probability of its target neuron and decreased the delay between the onset of a granule cell train and evoked firing in postsynaptic targets. Thus, we conclude that the granule cell to CA3 synapses are 'conditional detonators,' dependent on granule cell firing pattern. In addition, we suggest that information in single granule cells is converted into a temporal delay code in target CA3 pyramidal cells and interneurons. These data demonstrate how a neural circuit of the CNS may process information.

  1. Cold atmospheric plasma treatment selectively targets head and neck squamous cell carcinoma cells.

    Science.gov (United States)

    Guerrero-Preston, Rafael; Ogawa, Takenori; Uemura, Mamoru; Shumulinsky, Gary; Valle, Blanca L; Pirini, Francesca; Ravi, Rajani; Sidransky, David; Keidar, Michael; Trink, Barry

    2014-10-01

    The treatment of locoregional recurrence (LRR) of head and neck squamous cell carcinoma (HNSCC) often requires a combination of surgery, radiation therapy and/or chemotherapy. Survival outcomes are poor and the treatment outcomes are morbid. Cold atmospheric plasma (CAP) is an ionized gas produced at room temperature under laboratory conditions. We have previously demonstrated that treatment with a CAP jet device selectively targets cancer cells using in vitro melanoma and in vivo bladder cancer models. In the present study, we wished to examine CAP selectivity in HNSCC in vitro models, and to explore its potential for use as a minimally invasive surgical approach that allows for specific cancer cell or tumor tissue ablation without affecting the surrounding healthy cells and tissues. Four HNSCC cell lines (JHU-022, JHU-028, JHU-029, SCC25) and 2 normal oral cavity epithelial cell lines (OKF6 and NOKsi) were subjected to cold plasma treatment for durations of 10, 30 and 45 sec, and a helium flow of 20 l/min-1 for 10 sec was used as a positive treatment control. We showed that cold plasma selectively diminished HNSCC cell viability in a dose-response manner, as evidenced by MTT assays; the viability of the OKF6 cells was not affected by the cold plasma. The results of colony formation assays also revealed a cell-specific response to cold plasma application. Western blot analysis did not provide evidence that the cleavage of PARP occurred following cold plasma treatment. In conclusion, our results suggest that cold plasma application selectively impairs HNSCC cell lines through non-apoptotic mechanisms, while having a minimal effect on normal oral cavity epithelial cell lines.

  2. Campylobacter jejuni cell lysates differently target mitochondria and lysosomes on HeLa cells.

    Science.gov (United States)

    Canonico, B; Campana, R; Luchetti, F; Arcangeletti, M; Betti, M; Cesarini, E; Ciacci, C; Vittoria, E; Galli, L; Papa, S; Baffone, W

    2014-08-01

    Campylobacter jejuni is the most common cause of bacterial gastroenteritis in humans. The synthesis of cytolethal distending toxin appears essential in the infection process. In this work we evaluated the sequence of lethal events in HeLa cells exposed to cell lysates of two distinct strains, C. jejuni ATCC 33291 and C. jejuni ISS3. C. jejuni cell lysates (CCLys) were added to HeLa cell monolayers which were analysed to detect DNA content, death features, bcl-2 and p53 status, mitochondria/lysosomes network and finally, CD54 and CD59 alterations, compared to cell lysates of C. jejuni 11168H cdtA mutant. We found mitochondria and lysosomes differently targeted by these bacterial lysates. Death, consistent with apoptosis for C. jejuni ATCC 33291 lysate, occurred in a slow way (>48 h); concomitantly HeLa cells increase their endolysosomal compartment, as a consequence of toxin internalization besides a simultaneous and partial lysosomal destabilization. C. jejuni CCLys induces death in HeLa cells mainly via a caspase-dependent mechanism although a p53 lysosomal pathway (also caspase-independent) seems to appear in addition. In C. jejuni ISS3-treated cells, the p53-mediated oxidative degradation of mitochondrial components seems to be lost, inducing the deepest lysosomal alterations. Furthermore, CD59 considerably decreases, suggesting both a degradation or internalisation pathway. CCLys-treated HeLa cells increase CD54 expression on their surface, because of the action of lysate as its double feature of toxin and bacterial peptide. In conclusion, we revealed that C. jejuni CCLys-treated HeLa cells displayed different features, depending on the particular strain.

  3. 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

  4. Targeting Head and Neck Cancer Stem Cells: Current Advances and Future Challenges.

    Science.gov (United States)

    Birkeland, A C; Owen, J H; Prince, M E

    2015-11-01

    Cancer stem cells (CSCs), or tumor-initiating cells, comprise a subset of tumor cells with demonstrated ability for tumor growth, invasion, metastasis, and resistance to chemotherapy and radiation. Targeting of CSCs remains an attractive yet elusive therapeutic option, with the goal of increasing specificity and effectiveness in tumor eradication, as well as decreasing off-target or systemic toxicity. Research into further characterization and targeted therapy toward head and neck CSCs is an active and rapidly evolving field. This review discusses the current state of research into therapy against head and neck CSCs and future directions for targeted therapy.

  5. New Strategies in Engineering T-cell Receptor Gene-Modified T cells to More Effectively Target Malignancies.

    Science.gov (United States)

    Schmitt, Thomas M; Stromnes, Ingunn M; Chapuis, Aude G; Greenberg, Philip D

    2015-12-01

    The immune system, T cells in particular, have the ability to target and destroy malignant cells. However, antitumor immune responses induced from the endogenous T-cell repertoire are often insufficient for the eradication of established tumors, as illustrated by the failure of cancer vaccination strategies or checkpoint blockade for most tumors. Genetic modification of T cells to express a defined T-cell receptor (TCR) can provide the means to rapidly generate large numbers of tumor-reactive T cells capable of targeting tumor cells in vivo. However, cell-intrinsic factors as well as immunosuppressive factors in the tumor microenvironment can limit the function of such gene-modified T cells. New strategies currently being developed are refining and enhancing this approach, resulting in cellular therapies that more effectively target tumors and that are less susceptible to tumor immune evasion.

  6. Targeting Prostate Cancer Cells by Combined Oxidative Stress Induction and Androgen Receptor Antagonism

    Science.gov (United States)

    2015-08-01

    AD_________________ Award Number: W81XWH-12-1-0340 TITLE: Targeting Prostate Cancer Cells by Combined Oxidative Stress Induction and Androgen...COVERED 1 Aug 2014 - 21 Jul 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Targeting Prostate Cancer Cells by Combined Oxidative Stress Induction and

  7. A general functional response of cytotoxic T lymphocyte-mediated killing of target cells.

    Science.gov (United States)

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

    2014-04-15

    Cytotoxic T lymphocytes (CTLs) kill virus-infected cells and tumor cells, and play a critical role in immune protection. Our knowledge of how the CTL killing efficiency varies with CTL and target cell numbers is limited. Here, we simulate a region of lymphoid tissue using a cellular Potts model to characterize the functional response of CTL killing of target cells, and find that the total killing rate saturates both with the CTL and the target cell densities. The relative saturation in CTL and target cell densities is determined by whether a CTL can kill multiple target cells at the same time, and whether a target cell can be killed by many CTLs together. We find that all the studied regimes can be well described by a double-saturation (DS) function with two different saturation constants. We show that this DS model can be mechanistically derived for the cases where target cells are killed by a single CTL. For the other cases, a biological interpretation of the parameters is still possible. Our results imply that this DS function can be used as a tool to predict the cellular interactions in cytotoxicity data.

  8. Targeted Lymphoma Cell Death by Novel Signal Transduction Modifications

    Science.gov (United States)

    2011-07-01

    binding via direct visualization . negative #41 HB22.7 Figure 11. Ramos B cells were either incubated with anti-mouse FITC (negative), HB22.7 + anti...plemented with 10% FCS and incubated with AET - activated sheep red blood cells (SRBC) for 1 h. B-cells were collected at the interface after centrifugation...prepared and incubated with cells (4 9 104 cells/ml) for 4 days. Percent cell killing was quan- tified by visual examination using trypan blue dye exclusion

  9. Expression of Glycosylphosphatidylinositol-Anchored CD59 on Target Cells Enhances Human NK Cell-Mediated Cytotoxicity1

    OpenAIRE

    2006-01-01

    NK cell-mediated cytotoxicity of target cells is the result of a balance between the activating and inhibitory signals provided by their respective ligand-receptor interactions. In our current study, we have investigated the significance of CD59 on human target cells in modulating this process. A range of CD59 site-specific Abs were used in NK cytotoxicity blocking studies against the CD59-expressing K562 target cell line. Significantly reduced cytotoxicity was observed in the presence of Abs...

  10. Immuno nanoparticles integrated electrical control of targeted cancer cell development using whole cell bioelectronic device.

    Science.gov (United States)

    Hondroulis, Evangelia; Zhang, Rui; Zhang, Chengxiao; Chen, Chunying; Ino, Kosuke; Matsue, Tomokazu; Li, Chen-Zhong

    2014-01-01

    Electrical properties of cells determine most of the cellular functions, particularly ones which occur in the cell's membrane. Manipulation of these electrical properties may provide a powerful electrotherapy option for the treatment of cancer as cancerous cells have been shown to be more electronegative than normal proliferating cells. Previously, we used an electrical impedance sensing system (EIS) to explore the responses of cancerous SKOV3 cells and normal HUVEC cells to low intensity (electric fields, determining that the optimal frequency for SKOV3 proliferation arrest was 200 kHz, without harming the non-cancerous HUVECs. In this study, to determine if these effects are cell type dependant, human breast adenocarcinoma cells (MCF7) were subjected to a range of frequencies (50 kHz-2 MHz) similar to the previously tested SKOV3. For the MCF7, an optimal frequency of 100 kHz was determined using the EIS, indicating a higher sensitivity towards the applied field. Further experiments specifically targeting the two types of cancer cells using HER2 antibody functionalized gold nanoparticles (HER2-AuNPs) were performed to determine if enhanced electric field strength can be induced via the application of nanoparticles, consequently leading to the killing of the cancerous cells without affecting non cancerous HUVECs and MCF10a providing a platform for the development of a non-invasive cancer treatment without any harmful side effects. The EIS was used to monitor the real-time consequences on cellular viability and a noticeable decrease in the growth profile of the MCF7 was observed with the application of the HER2-AuNPs and the electric fields indicating specific inhibitory effects on dividing cells in culture. To further understand the effects of the externally applied field to the cells, an Annexin V/EthD-III assay was performed to determine the cell death mechanism indicating apoptosis. The zeta potential of the SKOV3 and the MCF7 before and after incorporation of

  11. Vesicle-associated membrane protein 7 (VAMP-7) is essential for target cell killing in a natural killer cell line.

    Science.gov (United States)

    Marcet-Palacios, Marcelo; Odemuyiwa, Solomon O; Coughlin, Jason J; Garofoli, Daniella; Ewen, Catherine; Davidson, Courtney E; Ghaffari, Mazyar; Kane, Kevin P; Lacy, Paige; Logan, Michael R; Befus, A Dean; Bleackley, R Chris; Moqbel, Redwan

    2008-02-15

    Natural killer cells recognize and induce apoptosis in foreign, transformed or virus-infected cells through the release of perforin and granzymes from secretory lysosomes. Clinically, NK-cell mediated killing is a major limitation to successful allo- and xenotransplantation. The molecular mechanisms that regulate the fusion of granzyme B-containing secretory lysosomes to the plasma membrane in activated NK cells, prior to target cell killing, are not fully understood. Using the NK cell line YT-Indy as a model, we have investigated the expression of SNAP REceptors (SNAREs), both target (t-) and vesicular (v-) SNAREs, and their function in granzyme B-mediated target cell killing. Our data showed that YT-Indy cells express VAMP-7 and SNAP-23, but not VAMP-2. VAMP-7 was associated with granzyme B-containing lysosomal granules. Using VAMP-7 small interfering RNA (siRNA), we successfully knocked down the expression of VAMP-7 protein in YT-Indy to less than 10% of untreated cells in 24h. VAMP7-deficient YT-Indy cells activated via co-culture with Jurkat cells released <1ng/mL of granzyme B, compared to 1.5-2.5 microg/mL from controls. Using Jurkat cells as targets, we showed a 7-fold reduction in NK cell-mediated killing by VAMP-7 deficient YT-Indy cells. Our results show that VAMP-7 is a crucial component of granzyme B release and target cell killing in the NK cell line YT-Indy. Thus, targeting VAMP-7 expression specifically with siRNA, following transplantation, may be a viable strategy for preventing NK cell-mediated transplant rejection, in vivo.

  12. 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.

  13. Targeted Therapy for Renal Cell Carcinoma: a Prospective study

    Directory of Open Access Journals (Sweden)

    Robin Joshi

    2015-06-01

    Conclusions: In our cohort, use of sunitinib showed similar outcome to previously published articles. Our study supports the use of sunitinib in metastatic renal cell carcinoma. Keywords: metastatic renal cell carcinoma; sunitinib; tyrosine kinase inhibitor.

  14. Autoantigenic targets of B-cell receptors derived from chronic lymphocytic leukemias bind to and induce proliferation of leukemic cells.

    Science.gov (United States)

    Zwick, Carsten; Fadle, Natalie; Regitz, Evi; Kemele, Maria; Stilgenbauer, Stephan; Bühler, Andreas; Pfreundschuh, Michael; Preuss, Klaus-Dieter

    2013-06-06

    Antigenic targets of the B-cell receptor (BCR) derived from malignant cells in chronic lymphocytic leukemia (CLL) might play a role in the pathogenesis of this neoplasm. We screened human tissue-derived protein macroarrays with antigen-binding fragments derived from 47 consecutive cases of CLL. An autoantigenic target was identified for 12/47 (25.5%) of the cases, with 3 autoantigens being the target of the BCRs from 2 patients each. Recombinantly expressed autoantigens bound specifically to the CLL cells from which the BCR used for the identification of the respective autoantigen was derived. Moreover, binding of the autoantigen to the respective leukemic cells induced a specific activation and proliferation of these cells. In conclusion, autoantigens are frequent targets of CLL-BCRs. Their specific binding to and induction of proliferation in the respective leukemic cells provide the most convincing evidence to date for the long-time hypothesized role of autoantigens in the pathogenesis of CLL.

  15. A drug target that stimulates development of healthy stem cells

    Science.gov (United States)

    Scientists have overcome a major impediment to the development of effective stem cell therapies by studying mice that lack CD47, a protein found on the surface of both healthy and cancer cells. They discovered that cells obtained from the lungs of CD47-de

  16. Genetically Programmed Clusters of Gold Nanoparticles for Cancer Cell-Targeted Photothermal Therapy.

    Science.gov (United States)

    Oh, Mi Hwa; Yu, Jeong Heon; Kim, Insu; Nam, Yoon Sung

    2015-10-14

    Interpretations of the interactions of nanocarriers with biological cells are often complicated by complex synthesis of materials, broad size distribution, and heterogeneous surface chemistry. Herein, the major capsid proteins of an icosahedral T7 phage (55 nm in diameter) are genetically engineered to display a gold-binding peptide and a prostate cancer cell-binding peptide in a tandem sequence. The genetically modified phage attracts gold nanoparticles (AuNPs) to form a cluster of gold nanoparticles (about 70 nanoparticles per phage). The cluster of AuNPs maintains cell-targeting functionality and exhibits excellent dispersion stability in serum. Under a very low light irradiation (60 mW cm(-2)), only targeted AuNP clusters kill the prostate cancer cells in minutes (not in other cell types), whereas neither nontargeted AuNP clusters nor citrate-stabilized AuNPs cause any significant cell death. The result suggests that the prostate cancer cell-targeted clusters of AuNPs are targeted to only prostate cancer cells and, when illuminated, generate local heating to more efficiently and selectively kill the targeted cancer cells. Our strategy can be generalized to target other types of cells and assemble other kinds of nanoparticles for a broad range of applications.

  17. Target Cell-Specific Modulation of Transmitter Release at Terminals from a Single Axon

    Science.gov (United States)

    Scanziani, Massimo; Gahwiler, Beat H.; Charpak, Serge

    1998-09-01

    In the hippocampus, a CA3 pyramidal cell forms excitatory synapses with thousands of other pyramidal cells and inhibitory interneurons. By using sequential paired recordings from three connected cells, we show that the presynaptic properties of CA3 pyramidal cell terminals, belonging to the same axon, differ according to the type of target cell. Activation of presynaptic group III metabotropic glutamate receptors decreases transmitter release only at terminals contacting CA1 interneurons but not CA1 pyramidal cells. Furthermore, terminals contacting distinct target cells show different frequency facilitation. On the basis of these results, we conclude that the pharmacological and physiological properties of presynaptic terminals are determined, at least in part, by the target cells.

  18. Mesenchymal stem cells as therapeutic delivery vehicles targeting tumor stroma

    DEFF Research Database (Denmark)

    Serakinci, Nedime; Christensen, Rikke; Sørensen, Flemming Brandt

    2011-01-01

    The field of stem cell biology continues to evolve by characterization of further types of stem cells and by exploring their therapeutic potential for experimental and clinical applications. Human mesenchymal stem cells (hMSCs) are one of the most promising candidates simply because...... better understanding and in vivo supporting data. The homing ability of hMSCs was investigated by creating a human xenograft model by transplanting an ovarian cancer cell line into immunocompromised mice. Then, genetically engineered hMSC-telo1 cells were injected through the tail vein...

  19. A visual targeting system for the microinjection of unstained adherent cells.

    Science.gov (United States)

    Becattini, Gabriele; Mattos, Leonardo S; Caldwell, Darwin G

    2013-02-01

    Automatic localization and targeting are critical steps in automating the process of microinjecting adherent cells. This process is currently performed manually by highly trained operators and is characterized as a laborious task with low success rate. Therefore, automation is desired to increase the efficiency and consistency of the operations. This research offers a contribution to this procedure through the development of a vision system for a robotic microinjection setup. Its goals are to automatically locate adherent cells in a culture dish and target them for a microinjection. Here the major concern was the achievement of an error-free targeting system to guarantee high consistency in microinjection experiments. To accomplish this, a novel visual targeting algorithm integrating different image processing techniques was proposed. This framework employed defocusing microscopy to highlight cell features and improve cell segmentation and targeting reliability. Three main image processing techniques, operating at three different focus levels in a bright field (BF) microscope, were used: an anisotropic contour completion (ACC) method, a local intensity variation background-foreground classifier, and a grayscale threshold-based segmentation. The proposed framework combined information gathered by each of these methods using a validation map and this was shown to provide reliable cell targeting results. Experiments conducted with sets of real images from two different cell lines (CHO-K1 and HEK), which contained a total of more than 650 cells, yielded flawless targeting results along with a cell detection ratio greater than 50%.

  20. Targeting eradication of malignant cells derived from human bone marrow mesenchymal stromal cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yingbin [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); School of Life Science, Southwest University, Chongqing 400715 (China); Cai, Shaoxi, E-mail: sxcai@cqu.edu.cn [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Yang, Li [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); College of Pharmacy, Jinan University, Guangzhou 510632 (China); Yu, Shuhui [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Library of Southwest University, Chongqing 400715 (China); Jiang, Jiahuan; Yan, Xiaoqing [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Zhang, Haoxing [School of Life Science, Southwest University, Chongqing 400715 (China); Liu, Lan [Department of Laboratory of Medicine, Children' s Hospital of Chongqin Medical University, Chongqing 400014 (China); Liu, Qun [College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041 (China); Du, Jun [Center of Microbiology, Biochemistry, and Pharmacology, School of Pharmaceutical Science, Sun Yat-Sen University, Guangzhou 510080 (China); Cai, Shaohui [College of Pharmacy, Jinan University, Guangzhou 510632 (China); Sung, K.L. Paul [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Departments of Orthopaedic Surgery and Bioengineering, University of California, SD 0412 (United States)

    2010-12-10

    Human bone marrow mesenchymal stromal cells (hBMSC) have been shown to participate in malignant transformation. However, hampered by the low frequency of malignant transformation of hBMSC, we do not yet know how to prevent malignant transformation of implanted hBMSC. In this study, in order to establish a model for the eradication of hBMSC-derived malignant cells, a gene fusion consisting of a human telomerase (hTERT) promoter modified with both c-Myc and myeloid zinc finger protein2 (MZF-2) binding elements and followed by the E. coli cytosine deaminase (CD) and luciferase genes was stably transferred into hBMSC via lentiviral transduction; n-phosphonacelyl-L-aspartic acid (PALA) selection was used to generate malignant cell colonies derived from transduced hBMSC after treatment with the carcinogenic reagent BPDE. Cells that were amplified after PALA selection were used for transplantation and 5-FC pro-drug cytotoxicity tests. The results showed that PALA-resistant malignant cells could be generated from hBMSC co-induced with lentiviral transduction and treatment with Benzo(a)pyrene Diol Epoxide (BPDE); the modification of c-Myc and MZF-2 binding elements could remarkably enhance the transcriptional activities of the hTERT promoter in malignant cells, whereas transcriptional activity was depressed in normal hBMSC; malignant cells stably expressing CD under the control of the modified hTERT promoter could be eliminated by 5-FC administration. This study has provided a method for targeted eradication of malignant cells derived from hBMSC.

  1. Viral piracy: HIV-1 targets dendritic cells for transmission.

    Science.gov (United States)

    Lekkerkerker, Annemarie N; van Kooyk, Yvette; Geijtenbeek, Teunis B H

    2006-04-01

    Dendritic cells (DCs), the professional antigen presenting cells, are critical for host immunity by inducing specific immune responses against a broad variety of pathogens. Remarkably the human immunodeficiency virus-1 (HIV-1) subverts DC function leading to spread of the virus. At an early phase of HIV-1 transmission, DCs capture HIV-1 at mucosal surfaces and transmit the virus to T cells in secondary lymphoid tissues. Capture of the virus on DCs takes place via C-type lectins of which the dendritic cell-specific intercellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin (DC-SIGN) is the best studied. DC-SIGN-captured HIV-1 particles accumulate in CD81(+) multivesicular bodies (MVBs) in DCs and are subsequently transmitted to CD4+ T cells resulting in infection of T cells. The viral cell-to-cell transmission takes place at the DC-T cell interface termed the infectious synapse. Recent studies demonstrate that direct infection of DCs contributes to the transmission to T cells at a later phase. Moreover, the infected DCs may function as cellular reservoirs for HIV-1. This review discusses the different processes that govern viral piracy of DCs by HIV-1, emphasizing the intracellular routing of the virus from capture on the cell surface to egress in the infectious synapse.

  2. B cells as therapeutic targets in autoimmune neurological disorders.

    Science.gov (United States)

    Dalakas, Marinos C

    2008-10-01

    B cells have a fundamental role in the pathogenesis of various autoimmune neurological disorders, not only as precursors of antibody-producing cells, but also as important regulators of the T-cell activation process through their participation in antigen presentation, cytokine production, and formation of ectopic germinal centers in the intermeningeal spaces. Two B-cell trophic factors-BAFF (B-cell-activating factor) and APRIL (a proliferation-inducing ligand)-and their receptors are strongly upregulated in many immunological disorders of the CNS and PNS, and these molecules contribute to clonal expansion of B cells in situ. The availability of monoclonal antibodies or fusion proteins against B-cell surface molecules and trophic factors provides a rational approach to the treatment of autoimmune neurological diseases. This article reviews the role of B cells in autoimmune neurological disorders and summarizes the experience to date with rituximab, a B-cell-depleting monoclonal antibody against CD20, for the treatment of relapsing-remitting multiple sclerosis, autoimmune neuropathies, neuromyelitis optica, paraneoplastic neurological disorders, myasthenia gravis, and inflammatory myopathies. It is expected that ongoing controlled trials will establish the efficacy and long-term safety profile of anti-B-cell agents in several autoimmune neurological disorders, as well as exploring the possibility of a safe and synergistic effect with other immunosuppressants or immunomodulators.

  3. HLA-targeted flow cytometric sorting of blood cells allows separation of pure and viable microchimeric cell populations.

    Science.gov (United States)

    Drabbels, Jos J M; van de Keur, Carin; Kemps, Berit M; Mulder, Arend; Scherjon, Sicco A; Claas, Frans H J; Eikmans, Michael

    2011-11-10

    Microchimerism is defined by the presence of low levels of nonhost cells in a person. We developed a reliable method for separating viable microchimeric cells from the host environment. For flow cytometric cell sorting, HLA antigens were targeted with human monoclonal HLA antibodies (mAbs). Optimal separation of microchimeric cells (present at a proportion as low as 0.01% in artificial mixtures) was obtained with 2 different HLA mAbs, one targeting the chimeric cells and the other the background cells. To verify purity of separated cell populations, flow-sorted fractions of 1000 cells were processed for DNA analysis by HLA-allele-specific and Y-chromosome-directed real-time quantitative PCR assays. After sorting, PCR signals of chimeric DNA markers in the positive fractions were significantly enhanced compared with those in the presort samples, and they were similar to those in 100% chimeric control samples. Next, we demonstrate applicability of HLA-targeted FACS sorting after pregnancy by separating chimeric maternal cells from child umbilical cord mononuclear cells. Targeting allelic differences with anti-HLA mAbs with FACS sorting allows maximal enrichment of viable microchimeric cells from a background cell population. The current methodology enables reliable microchimeric cell detection and separation in clinical specimens.

  4. Target cell-dependent normalization of transmitter release at neocortical synapses.

    Science.gov (United States)

    Koester, Helmut J; Johnston, Daniel

    2005-05-01

    The efficacy and short-term modification of neocortical synaptic connections vary with the type of target neuron. We investigated presynaptic Ca2+ and release probability at single synaptic contacts between pairs of neurons in layer 2/3 of the rat neocortex. The amplitude of Ca2+ signals in boutons of pyramids contacting bitufted or multipolar interneurons or other pyramids was dependent on the target cell type. Optical quantal analysis at single synaptic contacts suggested that release probabilities are also target cell-specific. Both the Ca2+ signal and the release probability of different boutons of a pyramid contacting the same target cell varied little. We propose that the mechanisms that regulate the functional properties of boutons of a pyramid normalize the presynaptic Ca2+ influx and release probability for all those boutons that innervate the same target cell.

  5. [Research progress in developing reporter systems for the enrichment of positive cells with targeted genome modification].

    Science.gov (United States)

    Bai, Yichun; Xu, Kun; Wei, Zehui; Ma, Zheng; Zhang, Zhiying

    2016-01-01

    Targeted genome editing technology plays an important role in studies of gene function, gene therapy and transgenic breeding. Moreover, the efficiency of targeted genome editing is increased dramatically with the application of recently developed artificial nucleases such as ZFNs, TALENs and CRISPR/Cas9. However, obtaining positive cells with targeted genome modification is restricted to some extent by nucleases expression plasmid transfection efficiency, nucleases expression and activity, and repair efficiency after genome editing. Thus, the enrichment and screening of positive cells with targeted genome modification remains a problem that need to be solved. Surrogate reporter systems could be used to reflect the efficiency of nucleases indirectly and enrich genetically modified positive cells effectively, which may increase the efficiency of the enrichment and screening of positive cells with targeted genome modification. In this review, we mainly summarized principles and applications of reporter systems based on NHEJ and SSA repair mechanisms, which may provide references for related studies in future.

  6. Rapid and Cost-Effective Gene Targeting in Rat Embryonic Stem Cells by TALENs

    Institute of Scientific and Technical Information of China (English)

    Chang Tong; Guanyi Huang; Charles Ashton; Hongping Wu; Hexin Yan; Qi-Long Ying

    2012-01-01

    The rat is the preferred animal model in many areas of biomedical research and drug development.Genetic manipulation in rats has lagged behind that in mice due to the lack of efficient gene targeting tools.Previously,we generated a knockout rat via conventional homologous recombination in rat embryonic stem (ES) cells.Here,we show that efficient gene targeting in rat ES cells can be achieved quickly through transcription activator-like effector nuclease (TALEN)-mediated DNA double-strand breaks.Using the Golden Gate cloning technique,we constructed a pair of TALEN targeting vectors for the gene of interest in 5 days.After gene transfection,the targeted rat ES cell colonies were isolated,screened,and confirmed by PCR without the need of drug selection.Our results suggest that TALEN-mediated gene targeting is a superior means of establishing genetically modified rat ES cell lines with high efficiency and short turnaround time.

  7. The kinematics of cytotoxic lymphocytes influence their ability to kill target cells.

    Science.gov (United States)

    Bhat, Purnima; Leggatt, Graham; Matthaei, Klaus I; Frazer, Ian H

    2014-01-01

    Cytotoxic lymphocytes (CTL) have been reported to show a range of motility patterns from rapid long-range tracking to complete arrest, but how and whether these kinematics affect their ability to kill target cells is not known. Many in vitro killing assays utilize cell lines and tumour-derived cells as targets, which may be of limited relevance to the kinetics of CTL-mediated killing of somatic cells. Here, live-cell microscopy is used to examine the interactions of CTL and primary murine skin cells presenting antigens. We developed a qualitative and quantitative killing assay using extended-duration fluorescence time-lapse microscopy coupled with large-volume objective software-based data analysis to obtain population data of cell-to-cell interactions, motility and apoptosis. In vivo and ex vivo activated antigen-specific cytotoxic lymphocytes were added to primary keratinocyte targets in culture with fluorometric detection of caspase-3 activation in targets as an objective determinant of apoptosis. We found that activated CTL achieved contact-dependent apoptosis of non-tumour targets after a period of prolonged attachment - on average 21 hours - which was determined by target cell type, amount of antigen, and activation status of CTL. Activation of CTL even without engagement of the T cell receptor was sufficient to mobilise cells significantly above baseline, while the addition of cognate antigen further enhanced their motility. Highly activated CTL showed markedly increased vector displacement, and velocity, and lead to increased antigen-specific target cell death. These data show that the inherent kinematics of CTL correlate directly with their ability to kill non-tumour cells presenting cognate antigen.

  8. The kinematics of cytotoxic lymphocytes influence their ability to kill target cells.

    Directory of Open Access Journals (Sweden)

    Purnima Bhat

    Full Text Available Cytotoxic lymphocytes (CTL have been reported to show a range of motility patterns from rapid long-range tracking to complete arrest, but how and whether these kinematics affect their ability to kill target cells is not known. Many in vitro killing assays utilize cell lines and tumour-derived cells as targets, which may be of limited relevance to the kinetics of CTL-mediated killing of somatic cells. Here, live-cell microscopy is used to examine the interactions of CTL and primary murine skin cells presenting antigens. We developed a qualitative and quantitative killing assay using extended-duration fluorescence time-lapse microscopy coupled with large-volume objective software-based data analysis to obtain population data of cell-to-cell interactions, motility and apoptosis. In vivo and ex vivo activated antigen-specific cytotoxic lymphocytes were added to primary keratinocyte targets in culture with fluorometric detection of caspase-3 activation in targets as an objective determinant of apoptosis. We found that activated CTL achieved contact-dependent apoptosis of non-tumour targets after a period of prolonged attachment - on average 21 hours - which was determined by target cell type, amount of antigen, and activation status of CTL. Activation of CTL even without engagement of the T cell receptor was sufficient to mobilise cells significantly above baseline, while the addition of cognate antigen further enhanced their motility. Highly activated CTL showed markedly increased vector displacement, and velocity, and lead to increased antigen-specific target cell death. These data show that the inherent kinematics of CTL correlate directly with their ability to kill non-tumour cells presenting cognate antigen.

  9. Getting to the heart of the matter in cancer: Novel approaches to targeting cancer stem cells.

    Science.gov (United States)

    Colvin, Hugh; Mori, Masaki

    2017-01-01

    Cancer is one of the leading causes of deaths worldwide. While cancers may initially show good response to chemotherapy or radiotherapy, it is not uncommon for them to recur at a later date. This phenomenon may be explained by the existence of a small population of cancer stem cells, which are inherently resistant to anti-cancer treatment as well as being capable of self-renewal. Therefore, while most of the tumour bulk consisting of cells that are not cancer stem cells respond to treatment, the cancer stem cells remain, leading to disease recurrence. Following this logic, the effective targeting of cancer stem cells holds promise for providing long-term cure in individuals with cancer. Cancer stem cells, like normal stem cells are endowed with mechanisms to protect themselves against a wide range of insults including anti-cancer treatments, such as the enhancement of the DNA damage response and the ability to extrude drugs. It is therefore important to develop new strategies if cancer stem cells are to be eradicated. In this review, we describe the strategies that we have developed to target cancer stem cells. These strategies include the targeting of the histone demethylase jumonji, AT rich interactive domain 1B (JARID1B), which we found to be functionally significant in the maintenance of cancer stem cells. Other strategies being pursued include reprogramming of cancer stem cells and the targeting of a functional cell surface marker of liver cancer stem cells, the aminopeptidase CD13.

  10. Targeting Breast Cancer Stem Cells In Triple Negative Breast Cancer

    Science.gov (United States)

    2014-10-01

    tumorigenesis (tumorsphere formation) and BCSC, which are linked to increase development of chemotherapeutic resistance and relapse. Effective inhibition of...and& mouse&BC&cells&[5,&29]& Lep7n&&induces&protein&expression&and&ac7va7on&of& Notch1 ,&G3&and&4&in&human&BC&& ER+&and&ERG&&and&mouse&E0771&ER+&cells&[29...mouse&BC&cells&[5,&29]& Lep7n&&induces&protein&expression&and&ac7va7on&of& Notch1 ,&G3&and&4&in&human&BC&& ER+&and&ERG&&and&mouse&E0771&ER+&cells&[29

  11. Therapeutic targeting of myeloid-derived suppressor cells.

    Science.gov (United States)

    Ugel, Stefano; Delpozzo, Federica; Desantis, Giacomo; Papalini, Francesca; Simonato, Francesca; Sonda, Nada; Zilio, Serena; Bronte, Vincenzo

    2009-08-01

    Myeloid-derived suppressor cells (MDSCs) represent a subset of myeloid cells that expand under pathological conditions, such as cancer development, acute and chronic infections, trauma, bone marrow transplantations, and some autoimmune diseases. MDSCs mediate a negative regulation of the immune response by affecting different T lymphocyte subsets. Potential mechanisms, which underlie this inhibitory activity range from those requiring direct cell-to-cell contact with others, more indirect, and mediated by the modification of the microenvironment. Pharmacological inhibition of MDSC suppressive pathways is a promising strategy to overcome disease-induced immune defects, which might be a key step in enhancing the effectiveness of immune-based therapies.

  12. Cell-type-specific, Aptamer-functionalized Agents for Targeted Disease Therapy.

    Science.gov (United States)

    Zhou, Jiehua; Rossi, John J

    2014-06-17

    One hundred years ago, Dr. Paul Ehrlich popularized the "magic bullet" concept for cancer therapy in which an ideal therapeutic agent would only kill the specific tumor cells it targeted. Since then, "targeted therapy" that specifically targets the molecular defects responsible for a patient's condition has become a long-standing goal for treating human disease. However, safe and efficient drug delivery during the treatment of cancer and infectious disease remains a major challenge for clinical translation and the development of new therapies. The advent of SELEX technology has inspired many groundbreaking studies that successfully adapted cell-specific aptamers for targeted delivery of active drug substances in both in vitro and in vivo models. By covalently linking or physically functionalizing the cell-specific aptamers with therapeutic agents, such as siRNA, microRNA, chemotherapeutics or toxins, or delivery vehicles, such as organic or inorganic nanocarriers, the targeted cells and tissues can be specifically recognized and the therapeutic compounds internalized, thereby improving the local concentration of the drug and its therapeutic efficacy. Currently, many cell-type-specific aptamers have been developed that can target distinct diseases or tissues in a cell-type-specific manner. In this review, we discuss recent advances in the use of cell-specific aptamers for targeted disease therapy, as well as conjugation strategies and challenges.

  13. Protocells and their use for targeted delivery of multicomponent cargos to cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Brinker, Jeffrey C.; Ashley, Carlee Erin; Jiang, Xingmao; Liu, Juewen; Peabody, David S.; Wharton, Walker Richard; Carnes, Eric; Chackerian, Bryce; Willman, Cheryl L.

    2016-11-01

    Various embodiments provide materials and methods for synthesizing protocells for use in targeted delivery of cargo components to cancer cells. In one embodiment, the lipid bilayer can be fused to the porous particle core to form a protocell. The lipid bilayer can be modified with targeting ligands or other ligands to achieve targeted delivery of cargo components that are loaded within the protocell to a target cell, e.g., a type of cancer. Shielding materials can be conjugated to the surface of the lipid bilayer to reduce undesired non-specific binding.

  14. Identification of human embryonic progenitor cell targeting peptides using phage display.

    Directory of Open Access Journals (Sweden)

    Paola A Bignone

    Full Text Available Human pluripotent stem (hPS cells are capable of differentiation into derivatives of all three primary embryonic germ layers and can self-renew indefinitely. They therefore offer a potentially scalable source of replacement cells to treat a variety of degenerative diseases. The ability to reprogram adult cells to induced pluripotent stem (iPS cells has now enabled the possibility of patient-specific hPS cells as a source of cells for disease modeling, drug discovery, and potentially, cell replacement therapies. While reprogramming technology has dramatically increased the availability of normal and diseased hPS cell lines for basic research, a major bottleneck is the critical unmet need for more efficient methods of deriving well-defined cell populations from hPS cells. Phage display is a powerful method for selecting affinity ligands that could be used for identifying and potentially purifying a variety of cell types derived from hPS cells. However, identification of specific progenitor cell-binding peptides using phage display may be hindered by the large cellular heterogeneity present in differentiating hPS cell populations. We therefore tested the hypothesis that peptides selected for their ability to bind a clonal cell line derived from hPS cells would bind early progenitor cell types emerging from differentiating hPS cells. The human embryonic stem (hES cell-derived embryonic progenitor cell line, W10, was used and cell-targeting peptides were identified. Competition studies demonstrated specificity of peptide binding to the target cell surface. Efficient peptide targeted cell labeling was accomplished using multivalent peptide-quantum dot complexes as detected by fluorescence microscopy and flow cytometry. The cell-binding peptides were selective for differentiated hPS cells, had little or no binding on pluripotent cells, but preferential binding to certain embryonic progenitor cell lines and early endodermal hPS cell derivatives. Taken

  15. Specific targeting of tumor cells by lyophilisomes functionalized with antibodies

    NARCIS (Netherlands)

    van Bracht, Etienne; Stolle, Sarah; Hafmans, Theo G.; Boerman, Otto C.; Oosterwijk, Egbert; van Kuppevelt, Toin H.; Daamen, Willeke F.

    2014-01-01

    Lyophilisomes are a novel class of proteinaceous biodegradable nano/micro drug delivery capsules prepared by freezing, annealing and Iyophilization. In the present study, lyophilisomes were functionalized for active targeting by antibody conjugation in order to obtain a selective drug-carrier system

  16. Targeting of liposomes to HIV-1-infected cells by peptides derived from the CD4 receptor.

    Science.gov (United States)

    Slepushkin, V A; Salem, I I; Andreev, S M; Dazin, P; Düzgüneş, N

    1996-10-23

    Liposomes can be targeted to HIV-infected cells by either reconstituting transmembrane CD4 in the membrane or covalently coupling soluble CD4 to modified lipids. We investigated whether synthetic peptides could be used as ligands for targeting liposomes. A synthetic peptide from the complementarity determining region 2 (CDR-2)-like domain of CD4 could bind specifically to HIV-infected cells and mediate the binding of peptide-coupled liposomes to these cells. A peptide from the CDR-3-like domain of CD4 inhibited HIV-induced syncytia formation, but failed to target liposomes to infected cells. This apparent discrepancy may be due to the requirement for a conformational change in the CD4 receptor for the CDR-3 region to interact with the HIV envelope protein. Our results demonstrate the feasibility of using synthetic peptides to target liposomes containing antiviral drugs to HIV-infected cells.

  17. The hair follicle and its stem cells as drug delivery targets.

    Science.gov (United States)

    Hoffman, Robert M

    2006-05-01

    The hair follicle is a skin appendage with a complex structure containing many cell types that produce highly specialised proteins. The hair follicle is in a continuous cycle: anagen is the hair growth phase, catagen the involution phase and telogen is the resting phase. The follicle offers many potential therapeutic targets. Hoffman and colleagues have pioneered hair-follicle-specific targeting using liposomes to deliver small and large molecules, including genes. They have also pioneered ex vivo hair-follicle targeting with continued expression of the introduced gene following transplantation. Recently, it has been discovered that hair follicle stem cells are highly pluripotent and can form neurons, glial cells and other cell types, and this has suggested that hair follicle stem cells may serve as gene therapy targets for regenerative medicine.

  18. Targeted and ultrasound-triggered cancer cell injury using perfluorocarbon emulsion-loaded liposomes endowed with cancer cell-targeting and fusogenic capabilities.

    Science.gov (United States)

    Ninomiya, Kazuaki; Yamashita, Takahiro; Tanabe, Yamato; Imai, Miki; Takahashi, Kenji; Shimizu, Nobuaki

    2016-01-01

    This study investigated the targeting and ultrasound-triggered injury of cancer cells using anticancer drug-free liposomes that contained an emulsion of perfluoropentane (ePFC5) and were co-modified with avidin as a targeting ligand for cancer cells and the hemagglutinating virus of Japan (HVJ) envelope to promote liposome fusion with the cells. These liposomes are designated as ePFC5-loaded avidin/HVJ liposomes. ePFC5-loaded liposomes were sensitized to ultrasound irradiation. Liposomes modified with avidin alone (avidin liposomes) showed binding to MCF-7 human breast cancer cells, and liposomes modified with HVJ envelope alone (HVJ liposomes) were found to fuse with MCF-7 cells. The irradiation of MCF-7 cells with 1 MHz ultrasound (30s, 1.2 W/cm(2), duty ratio 30%) combined with ePFC5-loaded avidin/HVJ liposomes resulted in a decrease in cell viability at 1h after irradiation to 43% of that of controls without ultrasound irradiation or liposomes. The cell viability was lower than that of cells treated with ultrasound irradiation with ePFC5-loaded avidin liposomes or ePFC5-loaded HVJ liposomes. This indicates that co-modification of liposome with avidin and HVJ envelope could enhance ultrasound-induced cell injury in the presence of ePFC5-loaded liposomes.

  19. Targeted Delivery of Carbon Nanotubes to Cancer Cells

    Science.gov (United States)

    2009-09-01

    the linear fit ( Beer -Lambert law) of absorbance at 808 nm versus the B-CNT concentration. Ablation of mAb-CNT-Coated Cells with NIR Light. One million...4Department of Molecular and Cell Biology, The University of Texas at Dallas, Richardson, TX 5Department of Microbiology , University of Texas Southwestern

  20. Rhodacyanine derivative selectively targets cancer cells and overcomes tamoxifen resistance.

    Directory of Open Access Journals (Sweden)

    John Koren

    Full Text Available MKT-077, a rhodacyanine dye, was shown to produce cancer specific cell death. However, complications prevented the use of this compound beyond clinical trials. Here we describe YM-1, a derivative of MKT-077. We found that YM-1 was more cytotoxic and localized differently than MKT-077. YM-1 demonstrated this cytotoxicity across multiple cancer cell lines. This toxicity was limited to cancer cell lines; immortalized cell models were unaffected. Brief applications of YM-1 were found to be non-toxic. Brief treatment with YM-1 restored tamoxifen sensitivity to a refractory tamoxifen-resistant MCF7 cell model. This effect is potentially due to altered estrogen receptor alpha phosphorylation, an outcome precipitated by selective reductions in Akt levels (Akt/PKB. Thus, modifications to the rhodocyanine scaffold could potentially be made to improve efficacy and pharmacokinetic properties. Moreover, the impact on tamoxifen sensitivity could be a new utility for this compound family.

  1. Rhodacyanine derivative selectively targets cancer cells and overcomes tamoxifen resistance.

    Science.gov (United States)

    Koren, John; Miyata, Yoshinari; Kiray, Janine; O'Leary, John C; Nguyen, Lana; Guo, Jianping; Blair, Laura J; Li, Xiaokai; Li, Xiokai; Jinwal, Umesh K; Cheng, Jin Q; Gestwicki, Jason E; Dickey, Chad A

    2012-01-01

    MKT-077, a rhodacyanine dye, was shown to produce cancer specific cell death. However, complications prevented the use of this compound beyond clinical trials. Here we describe YM-1, a derivative of MKT-077. We found that YM-1 was more cytotoxic and localized differently than MKT-077. YM-1 demonstrated this cytotoxicity across multiple cancer cell lines. This toxicity was limited to cancer cell lines; immortalized cell models were unaffected. Brief applications of YM-1 were found to be non-toxic. Brief treatment with YM-1 restored tamoxifen sensitivity to a refractory tamoxifen-resistant MCF7 cell model. This effect is potentially due to altered estrogen receptor alpha phosphorylation, an outcome precipitated by selective reductions in Akt levels (Akt/PKB). Thus, modifications to the rhodocyanine scaffold could potentially be made to improve efficacy and pharmacokinetic properties. Moreover, the impact on tamoxifen sensitivity could be a new utility for this compound family.

  2. Dendritic cell based PSMA immunotherapy for prostate cancer using a CD40-targeted adenovirus vector.

    Directory of Open Access Journals (Sweden)

    Briana Jill Williams

    Full Text Available Human prostate tumor vaccine and gene therapy trials using ex vivo methods to prime dendritic cells (DCs with prostate specific membrane antigen (PSMA have been somewhat successful, but to date the lengthy ex vivo manipulation of DCs has limited the widespread clinical utility of this approach. Our goal was to improve upon cancer vaccination with tumor antigens by delivering PSMA via a CD40-targeted adenovirus vector directly to DCs as an efficient means for activation and antigen presentation to T-cells. To test this approach, we developed a mouse model of prostate cancer by generating clonal derivatives of the mouse RM-1 prostate cancer cell line expressing human PSMA (RM-1-PSMA cells. To maximize antigen presentation in target cells, both MHC class I and TAP protein expression was induced in RM-1 cells by transduction with an Ad vector expressing interferon-gamma (Ad5-IFNγ. Administering DCs infected ex vivo with CD40-targeted Ad5-huPSMA, as well as direct intraperitoneal injection of the vector, resulted in high levels of tumor-specific CTL responses against RM-1-PSMA cells pretreated with Ad5-IFNγ as target cells. CD40 targeting significantly improved the therapeutic antitumor efficacy of Ad5-huPSMA encoding PSMA when combined with Ad5-IFNγ in the RM-1-PSMA model. These results suggest that a CD-targeted adenovirus delivering PSMA may be effective clinically for prostate cancer immunotherapy.

  3. Dendritic cell based PSMA immunotherapy for prostate cancer using a CD40-targeted adenovirus vector.

    Science.gov (United States)

    Williams, Briana Jill; Bhatia, Shilpa; Adams, Lisa K; Boling, Susan; Carroll, Jennifer L; Li, Xiao-Lin; Rogers, Donna L; Korokhov, Nikolay; Kovesdi, Imre; Pereboev, Alexander V; Curiel, David T; Mathis, J Michael

    2012-01-01

    Human prostate tumor vaccine and gene therapy trials using ex vivo methods to prime dendritic cells (DCs) with prostate specific membrane antigen (PSMA) have been somewhat successful, but to date the lengthy ex vivo manipulation of DCs has limited the widespread clinical utility of this approach. Our goal was to improve upon cancer vaccination with tumor antigens by delivering PSMA via a CD40-targeted adenovirus vector directly to DCs as an efficient means for activation and antigen presentation to T-cells. To test this approach, we developed a mouse model of prostate cancer by generating clonal derivatives of the mouse RM-1 prostate cancer cell line expressing human PSMA (RM-1-PSMA cells). To maximize antigen presentation in target cells, both MHC class I and TAP protein expression was induced in RM-1 cells by transduction with an Ad vector expressing interferon-gamma (Ad5-IFNγ). Administering DCs infected ex vivo with CD40-targeted Ad5-huPSMA, as well as direct intraperitoneal injection of the vector, resulted in high levels of tumor-specific CTL responses against RM-1-PSMA cells pretreated with Ad5-IFNγ as target cells. CD40 targeting significantly improved the therapeutic antitumor efficacy of Ad5-huPSMA encoding PSMA when combined with Ad5-IFNγ in the RM-1-PSMA model. These results suggest that a CD-targeted adenovirus delivering PSMA may be effective clinically for prostate cancer immunotherapy.

  4. Investigation of the strategies for targeting of the afterglow nanoparticles to tumor cells.

    Science.gov (United States)

    Rashidi, Leila Hossein; Homayoni, Homa; Zou, Xiaoju; Liu, Li; Chen, Wei

    2016-03-01

    Afterglow nanoparticles have been widely investigated as new agents for cancer imaging and as a light source for photodynamic activation for cancer treatment. For both applications, the targeting of the afterglow nanoparticles to tumor cells is an important and challenging issue. Here we report the strategies for targeting Sr3MgSi2O8:Eu(2+),Dy(3+) afterglow nanoparticles to tumor cells by conjugating with variety of targeting molecules such as folic acid, RGD peptide, and R-11 peptide. For folic acid targeting, experimental observations were conducted on PC-3 cells (folate receptor negative), MCF-7 (folate receptor positive), and KB cells (folate receptor positive) to compare the cellular uptake and confirm targeted delivery. For the cyclic RGDfK peptide, experiments were carried out on the integrin αvβ3 positive MDA-MB-231 breast cancer cell line and the integrin αvβ3 negative MCF-7 breast cancer cell lines in order to compare the cellular uptakes. As for R11-SH peptide, cellular uptake of the afterglow nanoparticles was observed on LNCaP and PC3 prostate cancer cell lines. All the observations showed that the cellular uptakes of the nanoparticles were enhanced by conjugation to variety of targeting molecules which are specific for breast and prostate cancer cells.

  5. Oct4 targets regulatory nodes to modulate stem cell function.

    Directory of Open Access Journals (Sweden)

    Pearl A Campbell

    Full Text Available Stem cells are characterized by two defining features, the ability to self-renew and to differentiate into highly specialized cell types. The POU homeodomain transcription factor Oct4 (Pou5f1 is an essential mediator of the embryonic stem cell state and has been implicated in lineage specific differentiation, adult stem cell identity, and cancer. Recent description of the regulatory networks which maintain 'ES' have highlighted a dual role for Oct4 in the transcriptional activation of genes required to maintain self-renewal and pluripotency while concomitantly repressing genes which facilitate lineage specific differentiation. However, the molecular mechanism by which Oct4 mediates differential activation or repression at these loci to either maintain stem cell identity or facilitate the emergence of alternate transcriptional programs required for the realization of lineage remains to be elucidated. To further investigate Oct4 function, we employed gene expression profiling together with a robust statistical analysis to identify genes highly correlated to Oct4. Gene Ontology analysis to categorize overrepresented genes has led to the identification of themes which may prove essential to stem cell identity, including chromatin structure, nuclear architecture, cell cycle control, DNA repair, and apoptosis. Our experiments have identified previously unappreciated roles for Oct4 for firstly, regulating chromatin structure in a state consistent with self-renewal and pluripotency, and secondly, facilitating the expression of genes that keeps the cell poised to respond to cues that lead to differentiation. Together, these data define the mechanism by which Oct4 orchestrates cellular regulatory pathways to enforce the stem cell state and provides important insight into stem cell function and cancer.

  6. Targeted genome editing in human cells using CRISPR/Cas nucleases and truncated guide RNAs.

    Science.gov (United States)

    Fu, Yanfang; Reyon, Deepak; Joung, J Keith

    2014-01-01

    CRISPR RNA-guided nucleases have recently emerged as a robust genome-editing platform that functions in a wide range of organisms. To reduce off-target effects of these nucleases, we developed and validated a modified system that uses truncated guide RNAs (tru-gRNAs). The use of tru-gRNAs leads to decreases in off-target effects and does not generally compromise the on-target efficiencies of these genome-editing nucleases. In this chapter, we describe guidelines for identifying potential tru-gRNA target sites and protocols for measuring the on-target efficiencies of CRISPR RNA-guided nucleases in human cells.

  7. Pros and Cons of Antigen-Presenting Cell Targeted Tumor Vaccines

    Directory of Open Access Journals (Sweden)

    Cleo Goyvaerts

    2015-01-01

    Full Text Available In therapeutic antitumor vaccination, dendritic cells play the leading role since they decide if, how, when, and where a potent antitumor immune response will take place. Since the disentanglement of the complexity and merit of different antigen-presenting cell subtypes, antitumor immunotherapeutic research started to investigate the potential benefit of targeting these subtypes in situ. This review will discuss which antigen-presenting cell subtypes are at play and how they have been targeted and finally question the true meaning of targeting antitumor-based vaccines.

  8. Targeted liposomes for delivery of protein-based drugs into the cytoplasm of tumor cells

    NARCIS (Netherlands)

    Mastrobattista, E; Crommelin, DJA; Wilschut, J; Storm, G

    2002-01-01

    Our goal was to deliver therapeutically active macromolecules into the cytosol of target cells. First, attempts were made to prepare virosomes that specifically interact with OVCAR-3 cells (human ovarian cancer cells). Detergent solubilized influenza virus envelopes were reconstituted forming viroso

  9. Plectasin, a Fungal Defensin, Targets the Bacterial Cell Wall Precursor Lipid II

    DEFF Research Database (Denmark)

    Schneider, Tanja; Kruse, Thomas; Wimmer, Reinhard

    2010-01-01

    that plectasin, a fungal defensin, acts by directly binding the bacterial cell-wall precursor Lipid II. A wide range of genetic and biochemical approaches identify cell-wall biosynthesis as the pathway targeted by plectasin. In vitro assays for cell-wall synthesis identified Lipid II as the specific cellular...

  10. Nanoscale mapping and organization analysis of target proteins on cancer cells from B-cell lymphoma patients

    Energy Technology Data Exchange (ETDEWEB)

    Li, Mi [State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Xiao, Xiubin [Department of Lymphoma, Affiliated Hospital of Military Medical Academy of Sciences, Beijing 100071 (China); Liu, Lianqing, E-mail: lqliu@sia.cn [State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016 (China); Xi, Ning, E-mail: xin@egr.msu.edu [State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016 (China); Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong (China); Wang, Yuechao; Dong, Zaili [State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016 (China); Zhang, Weijing, E-mail: zhangwj3072@163.com [Department of Lymphoma, Affiliated Hospital of Military Medical Academy of Sciences, Beijing 100071 (China)

    2013-11-01

    CD20, a membrane protein highly expressed on most B-cell lymphomas, is an effective target demonstrated in clinical practice for treating B-cell non-Hodgkin's lymphoma (NHL). Rituximab is a monoclonal antibody against CD20. In this work, we applied atomic force microscopy (AFM) to map the nanoscale distribution of CD20 molecules on the surface of cancer cells from clinical B-cell NHL patients under the assistance of ROR1 fluorescence recognition (ROR1 is a specific cell surface marker exclusively expressed on cancer cells). First, the ROR1 fluorescence labeling experiments showed that ROR1 was expressed on cancer cells from B-cell lymphoma patients, but not on normal cells from healthy volunteers. Next, under the guidance of ROR1 fluorescence, the rituximab-conjugated AFM tips were moved to cancer cells to image the cellular morphologies and detect the CD20-rituximab interactions on the cell surfaces. The distribution maps of CD20 on cancer cells were constructed by obtaining arrays of (16×16) force curves in local areas (500×500 nm{sup 2}) on the cell surfaces. The experimental results provide a new approach to directly investigate the nanoscale distribution of target protein on single clinical cancer cells. - Highlights: • Cancer cells were recognized from healthy cells by ROR1 fluorescence labeling. • The nanoscale distribution of CD20 on cancer cells was characterized. • The distribution of CD20 was non-uniform on the surface of cancer cells.

  11. A one-step rectification of sperm cell targeting ensures the success of double fertilization

    Institute of Scientific and Technical Information of China (English)

    Jilei Huang; Yan Ju; Xiangfeng Wang; Quan Zhang; Sodmergen

    2015-01-01

    Successful fertilization in animals depends on competition among millions of sperm cells, whereas double fertilization in flowering plants usually involves just one pollen tube releasing two immobile sperm cells. It is largely a mystery how the plant sperm cells fuse efficiently with their female targets within an embryo sac. We show that the initial positioning of sperm cells upon discharge from the pollen tube is usually inopportune for gamete fusions and that adjustment of sperm cell targeting occurs through release and re-adhesion of one sperm cell, while the other connected sperm cell remains in stagnation. This enables proper adhesion of each sperm cell to a female gamete and coordinates the gamete fusions. Our findings reveal inner embryo sac dynamics that ensure the reproductive success of flowering plants and suggest a requirement for sperm cell differentiation as the basis of double fertilization.

  12. Chaetoglobosin A preferentially induces apoptosis in chronic lymphocytic leukemia cells by targeting the cytoskeleton

    DEFF Research Database (Denmark)

    Knudsen, Peter Boldsen; Hanna, B.; Ohl, S.

    2014-01-01

    . To provide insight into its mechanism of action, we showed that ChA targets filamentous actin in CLL cells and thereby induces cell cycle arrest and inhibits membrane ruffling and cell migration. Our data further revealed that Chaetoglobosin A prevents CLL cell activation and sensitizes them for treatment......Chronic lymphocytic leukemia (CLL) is an incurable malignancy of mature B cells. One of the major challenges in treatment of CLL is the achievement of a complete remission to prevent relapse of disease originating from cells within lymphoid tissues and subsequent chemoresistance. In search...... for novel drugs that target CLL cells also in protective microenvironments, we performed a fungal extract screen using cocultures of primary CLL cells with bone marrow-derived stromal cells. A metabolite produced by Penicillium aquamarinium was identified as Chaetoglobosin A, a member of the cytochalasan...

  13. Understanding and Targeting Cell Growth Networks in Breast Cancer

    Science.gov (United States)

    2010-04-01

    Briata P, et al. (2003) The Wnt/beta-catenin-->Pitx2 pathway controls the turnover of Pitx2 and other unstable mRNAs. Molecular Cell 12(5):1201-1211...transcripts. Molecular Cell 20(6):891-903. 20. Gherzi R, et al. (2004) A KH domain RNA binding protein, KSRP, promotes ARE-directed mRNA turnover by...recruiting the degradation machinery. Molecular Cell 14(5):571-583. 21. Kroll TT, Zhao WM, Jiang C, & Huber PW (2002) A homolog of FBP2/KSRP binds to

  14. Salinomycin encapsulated nanoparticles as a targeting vehicle for glioblastoma cells.

    Science.gov (United States)

    Tığlı Aydın, R Seda; Kaynak, Gökçe; Gümüşderelioğlu, Menemşe

    2016-02-01

    Salinomycin has been introduced as a novel alternative to traditional anti-cancer drugs. The aim of this study was to test a strategy designed to deliver salinomycin to glioblastoma cells in vitro. Salinomycin-encapsulated polysorbate 80-coated poly(lactic-co-glycolic acid) nanoparticles (P80-SAL-PLGA) were prepared and characterized with respect to particle size, morphology, thermal properties, drug encapsulation efficiency and controlled salinomycin-release behaviour. The in vitro cellular uptake of P80-SAL-PLGA (5 and 10 µM) or uncoated nanoparticles was assessed in T98G human glioblastoma cells, and the cell viability was investigated with respect to anti-growth activities. SAL, which was successfully transported to T98G glioblastoma cells via P80 coated nanoparticles (∼14% within 60 min), greatly decreased (p salinomycin delivery system in the treatment of human glioblastoma.

  15. Biodegradable nanoparticles for targeted ultrasound imaging of breast cancer cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Liu Jun [Department of Biomedical Engineering, Ohio State University, 270 Bevis Hall, 1080 Carmack Rd, Columbus, OH 43210 (United States); Li Jie [Department of Biomedical Engineering, Ohio State University, 270 Bevis Hall, 1080 Carmack Rd, Columbus, OH 43210 (United States); Rosol, Thomas J [Department of Veterinary Biosciences, Ohio State University, 1925 Coffey Rd, Columbus, OH 43210 (United States); Pan Xueliang [Department of Statistics, Ohio State University, 1958 Neil Avenue, Columbus, OH 43210 (United States); Voorhees, Jeffrey L [Ohio State Biochemistry Program, Ohio State University, 108 Aronoff Building, 318 West 12 Avenue, Columbus, OH 43210 (United States)

    2007-08-21

    Disease-specific enhanced imaging through a targeted agent promises to improve the specificity of medical ultrasound. Nanoparticles may provide unique advantages for targeted ultrasound imaging due to their novel physical and surface properties. In this study, we examined a nanoparticle agent developed from a biodegradable polymer, polylactic acid (PLA). The nanoparticles (mean diameter = 250 nm) were surface conjugated to an anti-Her2 antibody (i.e., Herceptin) for specific binding to breast cancer cells that overexpress Her2 receptors. We examined the targeting specificity and the resultant ultrasound enhancement in Her2-positive and negative cells. Flow cytometry and confocal imaging were used to assess the nanoparticle-cell binding. Her2-positive cells demonstrated substantial staining after incubation with nanoparticle/antibody conjugates, while minimal staining was found in Her2-negative cells, indicating receptor-specific binding of the conjugated PLA nanoparticles. In high-resolution ultrasound B-mode images, the average gray scale of the Her2-positive cells was consistently and significantly higher after nanoparticle treatment (133 {+-} 4 in treated cells versus 109 {+-} 4 in control, p < 0.001, n = 5), while no difference was detected in the cells that did not overexpress the receptors (117 {+-} 3 in treated cells versus 118 {+-} 5 in control). In conclusion, the feasibility of using targeted nanoparticles to enhance ultrasonic images was demonstrated in vitro. This may be a promising approach to target cancer biomarkers for site-specific ultrasound imaging.

  16. Targeting epidermal Langerhans cells by epidermal powder immunization

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Immune reactions to foreign or self-antigens lead to protective immunity and, sometimes, immune disorders such as allergies and autoimmune diseases. Antigen presenting cells (APC) including epidermal Langerhans cells (LCs) play an important role in the course and outcome of the immune reactions. Epidermal powder immunization (EPI) is a technology that offers a tool to manipulate the LCs and the potential to harness the immune reactions towards prevention and treatment of infectious diseases and immune disorders.

  17. Hyaluronic acid-conjugated liposome nanoparticles for targeted delivery to CD44 overexpressing glioblastoma cells

    Science.gov (United States)

    Hayward, Stephen L.; Wilson, Christina L.; Kidambi, Srivatsan

    2016-01-01

    Glioblastoma Multiforme (GBM) is a highly prevalent and deadly brain malignancy characterized by poor prognosis and restricted disease management potential. Despite the success of nanocarrier systems to improve drug/gene therapy for cancer, active targeting specificity remains a major hurdle for GBM. Additionally, since the brain is a multi-cell type organ, there is a critical need to develop an approach to distinguish between GBM cells and healthy brain cells for safe and successful treatment. In this report, we have incorporated hyaluronic acid (HA) as an active targeting ligand for GBM. To do so, we employed HA conjugated liposomes (HALNPs) to study the uptake pathway in key cells in the brain including primary astrocytes, microglia, and human GBM cells. We observed that the HALNPs specifically target GBM cells over other brain cells due to higher expression of CD44 in tumor cells. Furthermore, CD44 driven HALNP uptake into GBM cells resulted in lysosomal evasion and increased efficacy of Doxorubicin, a model anti-neoplastic agent, while the astrocytes and microglia cells exhibited extensive HALNP-lysosome co-localization and decreased antineoplastic potency. In summary, novel CD44 targeted lipid based nanocarriers appear to be proficient in mediating site-specific delivery of drugs via CD44 receptors in GBM cells, with an improved therapeutic margin and safety. PMID:27120809

  18. Functional genetic targeting of embryonic kidney progenitor cells ex vivo.

    Science.gov (United States)

    Junttila, Sanna; Saarela, Ulla; Halt, Kimmo; Manninen, Aki; Pärssinen, Heikki; Lecca, M Rita; Brändli, André W; Sims-Lucas, Sunder; Skovorodkin, Ilya; Vainio, Seppo J

    2015-05-01

    The embryonic mammalian metanephric mesenchyme (MM) is a unique tissue because it is competent to generate the nephrons in response to Wnt signaling. An ex vivo culture in which the MM is separated from the ureteric bud (UB), the natural inducer, can be used as a classic tubule induction model for studying nephrogenesis. However, technological restrictions currently prevent using this model to study the molecular genetic details before or during tubule induction. Using nephron segment-specific markers, we now show that tubule induction in the MM ex vivo also leads to the assembly of highly segmented nephrons. This induction capacity was reconstituted when MM tissue was dissociated into a cell suspension and then reaggregated (drMM) in the presence of human recombinant bone morphogenetic protein 7/human recombinant fibroblast growth factor 2 for 24 hours before induction. Growth factor-treated drMM also recovered the capacity for organogenesis when recombined with the UB. Cell tracking and time-lapse imaging of chimeric drMM cultures indicated that the nephron is not derived from a single progenitor cell. Furthermore, viral vector-mediated transduction of green fluorescent protein was much more efficient in dissociated MM cells than in intact mesenchyme, and the nephrogenic competence of transduced drMM progenitor cells was preserved. Moreover, drMM cells transduced with viral vectors mediating Lhx1 knockdown were excluded from the nephric tubules, whereas cells transduced with control vectors were incorporated. In summary, these techniques allow reproducible cellular and molecular examinations of the mechanisms behind nephrogenesis and kidney organogenesis in an ex vivo organ culture/organoid setting.

  19. Influence of interferon on the functional expression of natural killer target structures of murine lymphoma cells.

    Science.gov (United States)

    Marini, S; Guadagni, F; Bonmassar, E; Potenza, P; Giuliani, A

    1986-10-01

    Murine lymphoma cells (YAC-1), induced by Moloney leukemia virus, nontreated (YAC) or pretreated in vitro with interferon (YAC-IF), were tested for their susceptibility to natural killer (NK)-mediated cytolysis. In line with previous reports YAC-IF were less susceptible to NK lysis than YAC cells. In cold competition assay, YAC-IF inhibited cytotoxicity to a lesser extent than YAC lymphoma when labeled target YAC cells were used. However, when radioactive YAC-IF cells were used as targets, cold competition attained with both YAC and YAC-IF was essentially the same. Furthermore, effector splenocytes, depleted of NK effector cells through immunoabsorption on YAC monolayer, were inactive against both YAC and YAC-IF targets. On the other hand, effector lymphocytes, absorbed on YAC-IF monolayer, retained NK activity against YAC cells but not against YAC-IF targets. These results are compatible with the hypothesis that interferon (IF) modulates negatively a subset of "interferon-susceptible" (IFS) NK target structure(s) (TS) of YAC cells, which would then express membrane determinants not functionally present on YAC-IF cells. On the other hand YAC and YAC-IF cells share "interferon-resistant" (IFR) TS not affected by pretreatment with IF. In order to test whether IFS X TS and IFR X TS are present on the same cell or clonally distributed, YAC cells were cloned and tested for NK susceptibility following IF pretreatment. The results did not support the hypothesis of a clonal distribution of both IFS X TS and IFR X TS since IF pretreatment of all clones, obtained by limiting dilution, resulted in a net impairment of target susceptibility to NK effector cells.

  20. Generation of tumor-targeted human T lymphocytes from induced pluripotent stem cells for cancer therapy.

    Science.gov (United States)

    Themeli, Maria; Kloss, Christopher C; Ciriello, Giovanni; Fedorov, Victor D; Perna, Fabiana; Gonen, Mithat; Sadelain, Michel

    2013-10-01

    Progress in adoptive T-cell therapy for cancer and infectious diseases is hampered by the lack of readily available, antigen-specific, human T lymphocytes. Pluripotent stem cells could provide an unlimited source of T lymphocytes, but the therapeutic potential of human pluripotent stem cell-derived lymphoid cells generated to date remains uncertain. Here we combine induced pluripotent stem cell (iPSC) and chimeric antigen receptor (CAR) technologies to generate human T cells targeted to CD19, an antigen expressed by malignant B cells, in tissue culture. These iPSC-derived, CAR-expressing T cells display a phenotype resembling that of innate γδ T cells. Similar to CAR-transduced, peripheral blood γδ T cells, the iPSC-derived T cells potently inhibit tumor growth in a xenograft model. This approach of generating therapeutic human T cells 'in the dish' may be useful for cancer immunotherapy and other medical applications.

  1. Cell-mediated Delivery and Targeted Erosion of Noncovalently Crosslinked Hydrogels

    Science.gov (United States)

    Kiick, Kristi L. (Inventor); Yamaguchi, Nori (Inventor)

    2013-01-01

    A method for targeted delivery of therapeutic compounds from hydrogels is presented. The method involves administering to a cell a hydrogel in which a therapeutic compound is noncovalently bound to heparin.

  2. A novel strategy for cancer treatment:Targeting cancer stem cells

    Institute of Scientific and Technical Information of China (English)

    LIU Jia; MA LeiNa; WANG YiGang; LIU XinYuan; QIAN QiJun

    2008-01-01

    Cancer stem cell/tumor-initiating cell (CSC/TIC) is a subclass of cancer cells possessing parts of properties of normal stem cell. It has a high capacity of proliferation and plays a pivotal role in tumor recurrence and tumor resistance to radiotherapy and chemotherapy. At present, small molecule in-hibitors and fusion proteins are widely used in the CSC-targeting strategy. Gene-virotherapy, which uses oncolytic adenovirus as a vector to mediate the expression of therapeutic gene, shows a signifi-cant superiority to other regimens of cancer treatment and has a good efficacy in the treatment of solid tumors. Thus, it is a promising choice to apply gene-virotherapy into the CSC-targeting treatment. Based on the molecular mechanism underlying CSC self-renewal, a series of effective strategies for targeting CSC have been established. This review will summarize the recent research progresses on CSC-targeting treatment.

  3. Tapping Stem Cells to Target AMD: Challenges and Prospects

    Directory of Open Access Journals (Sweden)

    Caroline Brandl

    2015-01-01

    Full Text Available Human pluripotent stem cells (hPSCs are increasingly gaining attention in biomedicine as valuable resources to establish patient-derived cell culture models of the cell type known to express the primary pathology. The idea of “a patient in a dish” aims at basic, but also clinical, applications with the promise to mimic individual genetic and metabolic complexities barely reflected in current invertebrate or vertebrate animal model systems. This may particularly be true for the inherited and complex diseases of the retina, as this tissue has anatomical and physiological aspects unique to the human eye. For example, the complex age-related macular degeneration (AMD, the leading cause of blindness in Western societies, can be attributed to a large number of genetic and individual factors with so far unclear modes of mutual interaction. Here, we review the current status and future prospects of utilizing hPSCs, specifically induced pluripotent stem cells (iPSCs, in basic and clinical AMD research, but also in assessing potential treatment options. We provide an outline of concepts for disease modelling and summarize ongoing and projected clinical trials for stem cell-based therapy in late-stage AMD.

  4. Colon cancer stem cells: promise of targeted therapy.

    Science.gov (United States)

    Todaro, Matilde; Francipane, Maria Giovanna; Medema, Jan Paul; Stassi, Giorgio

    2010-06-01

    First developed for hematologic disorders, the concept of cancer stem cells (CSCs) was expanded to solid tumors, including colorectal cancer (CRC). The traditional model of colon carcinogenesis includes several steps that occur via mutational activation of oncogenes and inactivation of tumor suppressor genes. Intestinal epithelial cells exist for a shorter amount of time than that required to accumulate tumor-inducing genetic changes, so researchers have investigated the concept that CRC arises from the long-lived stem cells, rather than from the differentiated epithelial cells. Colon CSCs were originally identified through the expression of the CD133 glycoprotein using an antibody directed to its epitope AC133. It is not clear if CD133 is a marker of colon CSCs-other cell surface markers, such as epithelial-specific antigen, CD44, CD166, Musashi-1, CD29, CD24, leucine-rich repeat-containing G-protein-coupled receptor 5, and aldehyde dehydrogenase 1, have been proposed. In addition to initiating and sustaining tumor growth, CSCs are believed to mediate cancer relapse after chemotherapy. How can we identify and analyze colon CSCs and what agents are being designed to kill this chemotherapy-refractory population?

  5. MicroRNAs targeting TGFβ signalling underlie the regulatory T cell defect in multiple sclerosis.

    Science.gov (United States)

    Severin, Mary E; Lee, Priscilla W; Liu, Yue; Selhorst, Amanda J; Gormley, Matthew G; Pei, Wei; Yang, Yuhong; Guerau-de-Arellano, Mireia; Racke, Michael K; Lovett-Racke, Amy E

    2016-06-01

    Transforming growth factor beta (TGFβ) signalling is critical for regulatory T cell development and function, and regulatory T cell dysregulation is a common observation in autoimmune diseases, including multiple sclerosis. In a comprehensive miRNA profiling study of patients with multiple sclerosis naïve CD4 T cells, 19 differentially expressed miRNAs predicted to target the TGFβ signalling pathway were identified, leading to the hypothesis that miRNAs may be responsible for the regulatory T cell defect observed in patients with multiple sclerosis. Patients with multiple sclerosis had reduced levels of TGFβ signalling components in their naïve CD4 T cells. The differentially expressed miRNAs negatively regulated the TGFβ pathway, resulting in a reduced capacity of naïve CD4 T cells to differentiate into regulatory T cells. Interestingly, the limited number of regulatory T cells, that did develop when these TGFβ-targeting miRNAs were overexpressed, were capable of suppressing effector T cells. As it has previously been demonstrated that compromising TGFβ signalling results in a reduced regulatory T cell repertoire insufficient to control autoimmunity, and patients with multiple sclerosis have a reduced regulatory T cell repertoire, these data indicate that the elevated expression of multiple TGFβ-targeting miRNAs in naïve CD4 T cells of patients with multiple sclerosis impairs TGFβ signalling, and dampens regulatory T cell development, thereby enhancing susceptibility to developing multiple sclerosis.

  6. Glycoengineering of Human Cell Lines Using Zinc Finger Nuclease Gene Targeting

    DEFF Research Database (Denmark)

    Steentoft, Catharina; Bennett, Eric Paul; Clausen, Henrik

    2013-01-01

    Lectin affinity chromatography is a powerful technique for isolation of glycoproteins carrying a specific glycan structure of interest. However, the enormous diversity of glycans present on the cell surface, as well as on individual proteins, makes it difficult to isolate an entire glycoproteome...... with one or even a series of lectins. Here we present a technique to generate cell lines with homogenous truncated O-glycans using zinc finger nuclease gene targeting. Because of their simplified O-glycoproteome, the cells have been named SimpleCells. Glycoproteins from SimpleCells can be isolated...... in a single purification step by lectin chromatography performed on a long lectin column. This protocol describes Zinc finger nuclease gene targeting of human cells to simplify the glycoproteome, as well as lectin chromatography and isolation of glycopeptides from total cell lysates of SimpleCells....

  7. Polarizing T and B cell responses by APC-targeted subunit vaccines.

    Directory of Open Access Journals (Sweden)

    Gunnveig eGrødeland

    2015-07-01

    Full Text Available Current influenza vaccines mostly aim at the induction of specific neutralizing antibodies. While antibodies are important for protection against a particular virus strain, T cells can recognize epitopes that will offer broader protection against influenza. We have previously developed a DNA vaccine format by which protein antigens can be targeted specifically to receptors on antigen presenting cells (APCs. The DNA-encoded vaccine proteins are homodimers, each chain consisting of a targeting unit, a dimerization unit, and an antigen. The strategy of targeting antigen to APCs greatly enhances immune responses as compared to non-targeted controls. Furthermore, targeting of antigen to different receptors on APCs can polarize the immune response to different arms of immunity. Here, we discuss how targeting of hemagglutinin (HA to MHC class II molecules increases Th2 and IgG1 antibody responses, whereas targeting to chemokine receptors XCR1 or CCR1/3/5 increases Th1 and IgG2a responses, in addition to CD8+ T cell responses. We also discuss these results in relation to work published by others on APC-targeting. Differential targeting of APC surface molecules may allow the induction of tailor-made phenotypes of adaptive immune responses that are optimal for protection against various infectious agents, including influenza virus.

  8. Mesenchymal Stem Cells after Polytrauma: Actor and Target

    Directory of Open Access Journals (Sweden)

    Markus Huber-Lang

    2016-01-01

    Full Text Available Mesenchymal stem cells (MSCs are multipotent cells that are considered indispensable in regeneration processes after tissue trauma. MSCs are recruited to damaged areas via several chemoattractant pathways where they function as “actors” in the healing process by the secretion of manifold pro- and anti-inflammatory, antimicrobial, pro- and anticoagulatory, and trophic/angiogenic factors, but also by proliferation and differentiation into the required cells. On the other hand, MSCs represent “targets” during the pathophysiological conditions after severe trauma, when excessively generated inflammatory mediators, complement activation factors, and damage- and pathogen-associated molecular patterns challenge MSCs and alter their functionality. This in turn leads to complement opsonization, lysis, clearance by macrophages, and reduced migratory and regenerative abilities which culminate in impaired tissue repair. We summarize relevant cellular and signaling mechanisms and provide an up-to-date overview about promising future therapeutic MSC strategies in the context of severe tissue trauma.

  9. Re-programming tumour cell metabolism to treat cancer: no lone target for lonidamine

    Science.gov (United States)

    Bhutia, Yangzom D.; Babu, Ellappan; Ganapathy, Vadivel

    2016-01-01

    Tumour cell metabolism is very different from normal cell metabolism; cancer cells re-programme the metabolic pathways that occur in normal cells in such a manner that it optimizes their proliferation, growth and survival. Although this metabolic re-programming obviously operates to the advantage of the tumour, it also offers unique opportunities for effective cancer therapy. Molecules that target the tumour cell-specific metabolic pathways have potential as novel anti-cancer drugs. Lonidamine belongs to this group of molecules and is already in use in some countries for cancer treatment. It has been known for a long time that lonidamine interferes with energy production in tumour cells by inhibiting hexokinase II (HKII), a glycolytic enzyme. However, subsequent studies have uncovered additional pharmacological targets for the drug, which include the electron transport chain and the mitochondrial permeability transition pore, thus expanding the pharmacological effects of the drug on tumour cell metabolism. A study by Nancolas et al. in a recent issue of the Biochemical Journal identifies two additional new targets for lonidamine: the pyruvate transporter in the mitochondria and the H+-coupled monocarboxylate transporters in the plasma membrane (PM). It is thus becoming increasingly apparent that the anti-cancer effects of lonidamine do not occur through a single target; the drug works at multiple sites. Irrespective of the molecular targets, what lonidamine does in the end is to undo what the tumour cells have done in terms of re-programming cellular metabolism and mitochondrial function. PMID:27234586

  10. Re-programming tumour cell metabolism to treat cancer: no lone target for lonidamine.

    Science.gov (United States)

    Bhutia, Yangzom D; Babu, Ellappan; Ganapathy, Vadivel

    2016-06-01

    Tumour cell metabolism is very different from normal cell metabolism; cancer cells re-programme the metabolic pathways that occur in normal cells in such a manner that it optimizes their proliferation, growth and survival. Although this metabolic re-programming obviously operates to the advantage of the tumour, it also offers unique opportunities for effective cancer therapy. Molecules that target the tumour cell-specific metabolic pathways have potential as novel anti-cancer drugs. Lonidamine belongs to this group of molecules and is already in use in some countries for cancer treatment. It has been known for a long time that lonidamine interferes with energy production in tumour cells by inhibiting hexokinase II (HKII), a glycolytic enzyme. However, subsequent studies have uncovered additional pharmacological targets for the drug, which include the electron transport chain and the mitochondrial permeability transition pore, thus expanding the pharmacological effects of the drug on tumour cell metabolism. A study by Nancolas et al. in a recent issue of the Biochemical Journal identifies two additional new targets for lonidamine: the pyruvate transporter in the mitochondria and the H(+)-coupled monocarboxylate transporters in the plasma membrane (PM). It is thus becoming increasingly apparent that the anti-cancer effects of lonidamine do not occur through a single target; the drug works at multiple sites. Irrespective of the molecular targets, what lonidamine does in the end is to undo what the tumour cells have done in terms of re-programming cellular metabolism and mitochondrial function.

  11. Engineering of Targeted Nanoparticles for Cancer Therapy Using Internalizing Aptamers Isolated by Cell-Uptake Selection

    Science.gov (United States)

    Xiao, Zeyu; Levy-Nissenbaum, Etgar; Alexis, Frank; Lupták, Andrej; Teply, Benjamin A.; Chan, Juliana M.; Shi, Jinjun; Digga, Elise; Cheng, Judy; Langer, Robert; Farokhzad, Omid C.

    2012-01-01

    One of the major challenges in the development of targeted nanoparticles (NPs) for cancer therapy is to discover targeting ligands that allow for differential binding and uptake by the target cancer cells. Using prostate cancer (PCa) as a model disease, we developed a cell-uptake selection strategy to isolate PCa-specific internalizing 2'-Omethyl RNA aptamers (Apts) for NP incorporation. Twelve cycles of selection and counter-selection were done to obtain a panel of internalizing Apts, which can distinguish PCa cells from non-prostate and normal prostate cells. After Apt characterization, size minimization, and conjugation of the Apts with fluorescently-labeled polymeric NPs, the NP-Apt bioconjugates exhibit PCa specificity and enhancement in cellular uptake when compared to non-targeted NPs lacking the internalizing Apts. Furthermore, when docetaxel, a chemotherapeutic agent used for the treatment of PCa, was encapsulated within the NP-Apt, a significant improvement in cytotoxicity was achieved in targeted PCa cells. Rather than isolating high-affinity Apts as reported in previous selection processes, our selection strategy was designed to enrich cancer-cell specific internalizing Apts. A similar cell-uptake selection strategy may be used to develop specific internalizing ligands for a myriad of other diseases and can potentially facilitate delivering various molecules, including drugs and siRNAs, into cells. PMID:22214176

  12. Utilization of Rad51C promoter for transcriptional targeting of cancer cells

    Science.gov (United States)

    Li, Zhen; Jiang, Ying; Tian, Xiao; Seluanov, Andrei; Gorbunova, Vera; Mao, Zhiyong

    2014-01-01

    Cancer therapy that specifically targets malignant cells with minimal or no toxicity to normal tissue has been a long-standing goal of cancer research. Rad51 expression is elevated in a wide range of cancers and Rad51 promoter has been used to transcriptionally target tumor cells, however, a large size of Rad51 promoter limits its application for gene therapy. To identify novel tumor-specific promoters, we examined expression levels of Rad51 paralogs, Rad51B, Rad51C, and Rad51D as well as Rad52 in a panel of normal and tumor cell lines. We found that Rad51C is significantly overexpressed in cancer cells. The expression was up-regulated by approximately 6-fold at the mRNA level and 9-fold at the protein level. Interestingly, the 2064 bp long Rad51C promoter fragment was approximately 300-fold higher in cancer cells than in normal cells. A construct containing Rad51C promoter driving diphtheria toxin A efficiently killed several types of cancer cells with very mild effect to normal cells. These results underscore the potential of targeting the homologous recombination pathway in cancer cells and provide a proof of principle that the Rad51C promoter fragment can be used to transcriptionally target cancer cells. PMID:24742710

  13. Targeting and Imaging of Cancer Cells via Monosaccharide-Imprinted Fluorescent Nanoparticles

    Science.gov (United States)

    Wang, Shuangshou; Yin, Danyang; Wang, Wenjing; Shen, Xiaojing; Zhu, Jun-Jie; Chen, Hong-Yuan; Liu, Zhen

    2016-03-01

    The recognition of cancer cells is a key for cancer diagnosis and therapy, but the specificity highly relies on the use of biorecognition molecules particularly antibodies. Because biorecognition molecules suffer from some apparent disadvantages, such as hard to prepare and poor storage stability, novel alternatives that can overcome these disadvantages are highly important. Here we present monosaccharide-imprinted fluorescent nanoparticles (NPs) for targeting and imaging of cancer cells. The molecularly imprinted polymer (MIP) probe was fluorescein isothiocyanate (FITC) doped silica NPs with a shell imprinted with sialic acid, fucose or mannose as the template. The monosaccharide-imprinted NPs exhibited high specificity toward the target monosaccharides. As the template monosaccharides used are over-expressed on cancer cells, these monosaccharide-imprinted NPs allowed for specific targeting cancer cells over normal cells. Fluorescence imaging of human hepatoma carcinoma cells (HepG-2) over normal hepatic cells (L-02) and mammary cancer cells (MCF-7) over normal mammary epithelial cells (MCF-10A) by these NPs was demonstrated. As the imprinting approach employed herein is generally applicable and highly efficient, monosaccharide-imprinted NPs can be promising probes for targeting cancer cells.

  14. Folate-conjugated polymer micelles for active targeting to cancer cells: preparation, in vitro evaluation of targeting ability and cytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    You Jian [College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Li Xin [College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Cui Fude [College of Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang 110016 (China); Du Yongzhong [College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Yuan Hong [College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Hu Fuqiang [College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China)

    2008-01-30

    To obtain an active-targeting carrier to cancer cells, folate-conjugated stearic acid grafted chitosan oligosaccharide (Fa-CSOSA) was synthesized by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)-mediated coupling reaction. The substitution degree is 22.1%. The critical micelle concentrations (CMCs) of Fa-CSOSA were 0.017 and 0.0074 mg ml{sup -1} in distilled water and PBS (pH 7.4), respectively. The average volume size range of Fa-CSOSA micelles was 60-120 nm. The targeting ability of Fa-CSOSA micelles was investigated against two kinds of cell lines (A549 and Hela), which have different amounts of folate receptors in their surface. The results indicated that Fa-CSOSA micelles presented a targeting ability to the cells (Hela) with a higher expression of folate receptor during a short-time incubation (<6 h). As incubation proceeded, the special spatial structure of the micelles gradually plays a main role in cellular internalization of the micelles. Good internalization of the micelles into both Hela and A549 cells was shown. Then, paclitaxel (PTX) was encapsulated into the micelles, and the content of PTX in the micelles was about 4.8% (w/w). The average volume size range of PTX-loaded micelles was 150-340 nm. Furthermore, the anti-tumor efficacy in vitro was investigated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) method. The IC{sub 50} of Taxol (a clinical formulation containing PTX) on A549 and Hela cells was 7.0 and 11.0 {mu}g ml{sup -1}, respectively. The cytotoxicity of PTX-loaded micelles was improved sharply (IC{sub 50} on A549: 0.32 {mu}g ml{sup -1}; IC{sub 50} on Hela: 0.268 {mu}g ml{sup -1}). This is attributed to the increased intracellular delivery of the drug. The Fa-CSOSA micelles that are presented may be a promising active-targeting carrier candidate via folate mediation.

  15. Cancer cell signaling pathways targeted by spice-derived nutraceuticals.

    Science.gov (United States)

    Sung, Bokyung; Prasad, Sahdeo; Yadav, Vivek R; Aggarwal, Bharat B

    2012-01-01

    Extensive research within the last half a century has revealed that cancer is caused by dysregulation of as many as 500 different gene products. Most natural products target multiple gene products and thus are ideally suited for prevention and treatment of various chronic diseases, including cancer. Dietary agents such as spices have been used extensively in the Eastern world for a variety of ailments for millennia, and five centuries ago they took a golden journey to the Western world. Various spice-derived nutraceuticals, including 1'-acetoxychavicol acetate, anethole, capsaicin, cardamonin, curcumin, dibenzoylmethane, diosgenin, eugenol, gambogic acid, gingerol, thymoquinone, ursolic acid, xanthohumol, and zerumbone derived from galangal, anise, red chili, black cardamom, turmeric, licorice, fenugreek, clove, kokum, ginger, black cumin, rosemary, hop, and pinecone ginger, respectively, are the focus of this review. The modulation of various transcription factors, growth factors, protein kinases, and inflammatory mediators by these spice-derived nutraceuticals are described. The anticancer potential through the modulation of various targets is also the subject of this review. Although they have always been used to improve taste and color and as a preservative, they are now also used for prevention and treatment of a wide variety of chronic inflammatory diseases, including cancer.

  16. Mitochondrial targeted β-lapachone induces mitochondrial dysfunction and catastrophic vacuolization in cancer cells.

    Science.gov (United States)

    Ma, Jing; Lim, Chaemin; Sacher, Joshua R; Van Houten, Bennett; Qian, Wei; Wipf, Peter

    2015-11-01

    Mitochondria play important roles in tumor cell physiology and survival by providing energy and metabolites for proliferation and metastasis. As part of their oncogenic status, cancer cells frequently produce increased levels of mitochondrial-generated reactive oxygen species (ROS). However, extensive stimulation of ROS generation in mitochondria has been shown to be able to induce cancer cell death, and is one of the major mechanisms of action of many anticancer agents. We hypothesized that enhancing mitochondrial ROS generation through direct targeting of a ROS generator into mitochondria will exhibit tumor cell selectivity, as well as high efficacy in inducing cancer cell death. We thus synthesized a mitochondrial targeted version of β-lapachone (XJB-Lapachone) based on our XJB mitochondrial targeting platform. We found that the mitochondrial targeted β-lapachone is more efficient in inducing apoptosis compared to unconjugated β-lapachone, and the tumor cell selectivity is maintained. XJB-Lapachone also induced extensive cellular vacuolization and autophagy at a concentration not observed with unconjugated β-lapachone. Through characterization of mitochondrial function we revealed that XJB-Lapachone is indeed more capable of stimulating ROS generation in mitochondria, which led to a dramatic mitochondrial uncoupling and autophagic degradation of mitochondria. Taken together, we have demonstrated that targeting β-lapachone accomplishes higher efficacy through inducing ROS generation directly in mitochondria, resulting in extensive mitochondrial and cellular damage. XJB-Lapachone will thus help to establish a novel platform for the design of next generation mitochondrial targeted ROS generators for cancer therapy.

  17. Analysis of the role of homology arms in gene-targeting vectors in human cells.

    Directory of Open Access Journals (Sweden)

    Ayako Ishii

    Full Text Available Random integration of targeting vectors into the genome is the primary obstacle in human somatic cell gene targeting. Non-homologous end-joining (NHEJ, a major pathway for repairing DNA double-strand breaks, is thought to be responsible for most random integration events; however, absence of DNA ligase IV (LIG4, the critical NHEJ ligase, does not significantly reduce random integration frequency of targeting vector in human cells, indicating robust integration events occurring via a LIG4-independent mechanism. To gain insights into the mechanism and robustness of LIG4-independent random integration, we employed various types of targeting vectors to examine their integration frequencies in LIG4-proficient and deficient human cell lines. We find that the integration frequency of targeting vector correlates well with the length of homology arms and with the amount of repetitive DNA sequences, especially SINEs, present in the arms. This correlation was prominent in LIG4-deficient cells, but was also seen in LIG4-proficient cells, thus providing evidence that LIG4-independent random integration occurs frequently even when NHEJ is functionally normal. Our results collectively suggest that random integration frequency of conventional targeting vectors is substantially influenced by homology arms, which typically harbor repetitive DNA sequences that serve to facilitate LIG4-independent random integration in human cells, regardless of the presence or absence of functional NHEJ.

  18. Targeting Dendritic Cell Function during Systemic Autoimmunity to Restore Tolerance

    Directory of Open Access Journals (Sweden)

    Juan P. Mackern-Oberti

    2014-09-01

    Full Text Available Systemic autoimmune diseases can damage nearly every tissue or cell type of the body. Although a great deal of progress has been made in understanding the pathogenesis of autoimmune diseases, current therapies have not been improved, remain unspecific and are associated with significant side effects. Because dendritic cells (DCs play a major role in promoting immune tolerance against self-antigens (self-Ags, current efforts are focusing at generating new therapies based on the transfer of tolerogenic DCs (tolDCs during autoimmunity. However, the feasibility of this approach during systemic autoimmunity has yet to be evaluated. TolDCs may ameliorate autoimmunity mainly by restoring T cell tolerance and, thus, indirectly modulating autoantibody development. In vitro induction of tolDCs loaded with immunodominant self-Ags and subsequent cell transfer to patients would be a specific new therapy that will avoid systemic immunosuppression. Herein, we review recent approaches evaluating the potential of tolDCs for the treatment of systemic autoimmune disorders.

  19. Gene targeting in embryonic stem cells, II: conditional technologies

    Science.gov (United States)

    Genome modification via transgenesis has allowed researchers to link genotype and phenotype as an alternative approach to the characterization of random mutations through evolution. The synergy of technologies from the fields of embryonic stem (ES) cells, gene knockouts, and protein-mediated recombi...

  20. Lung Dendritic cells: Targets for therapy in allergic disease

    NARCIS (Netherlands)

    B.N.M. Lambrecht (Bart)

    2008-01-01

    textabstractDendritic cells are crucial in determining the functional outcome of allergen encounter in the lung. Antigen presentation by myeloid DCs leads to Th2 sensitization typical of allergic disease, whereas antigen presentation by plasmacytoid DCs serves to dampen inflammation. It is increasin

  1. Targeting cancer cells with folic acid-iminoboronate fluorescent conjugates.

    Science.gov (United States)

    Cal, Pedro M S D; Frade, Raquel F M; Chudasama, Vijay; Cordeiro, Carlos; Caddick, Stephen; Gois, Pedro M P

    2014-05-25

    Herein we present the synthesis of fluorescent 2-acetylbenzeneboronic acids that undergo B-N promoted conjugation with lysozyme and N-(2-aminoethyl) folic acid (EDA-FA), generating conjugates that are selectively recognized and internalized by cancer cells that over-express folic acid receptors.

  2. Targeted treatments in advanced renal cell carcinoma: focus on axitinib

    Directory of Open Access Journals (Sweden)

    Verzoni E

    2014-03-01

    Full Text Available Elena Verzoni, Paolo Grassi, Isabella Testa, Roberto Iacovelli, Pamela Biondani, Enrico Garanzini , Filippo De Braud, Giuseppe ProcopioDepartment of Medical Oncology 1, Fondazione IRCCS Istituto Nazionale Tumori, Milan, ItalyAbstract: Antiangiogenesis options have evolved rapidly in the last few years, with an increasing number of agents currently approved by the US Food and Drug Administration and European Medicines Agency. Angiogenesis inhibitors have been shown to be very effective for the treatment of metastatic renal cancer cell. Axitinib is a third-generation inhibitor of vascular endothelial growth factor receptor and is currently being developed for the treatment of various malignancies. The pharmacokinetic properties of axitinib may have a selective therapeutic effect, with minimal adverse reactions and enhanced safety. In a large Phase III study of previously treated patients with metastatic renal cell carcinoma, axitinib achieved a longer progression-free survival than sorafenib with an acceptable safety profile and good quality of life. This review focuses on the pharmacology, pharmacokinetics, and clinical activity of axitinib in the current treatment of renal cell carcinoma. The role of axitinib in the adjuvant and/or neoadjuvant setting needs to be evaluated in further clinical trials.Keywords: axitinib, renal cell carcinoma, vascular endothelial growth factor receptor, angiogenesis

  3. Targeting inflammation with autoantigen-specific T cells

    NARCIS (Netherlands)

    Guichelaar, T.

    2008-01-01

    Chronic autoimmune diseases are driven by cells that respond to tissue components of the body. Inflammation in diseases like rheumatoid arthritis, diabetes or multiple sclerosis, can be suppressed by drug therapy. However, the broad range of immunosuppressive action of these drugs often does not res

  4. Increasing intracellular bioavailable copper selectively targets prostate cancer cells.

    Science.gov (United States)

    Cater, Michael A; Pearson, Helen B; Wolyniec, Kamil; Klaver, Paul; Bilandzic, Maree; Paterson, Brett M; Bush, Ashley I; Humbert, Patrick O; La Fontaine, Sharon; Donnelly, Paul S; Haupt, Ygal

    2013-07-19

    The therapeutic efficacy of two bis(thiosemicarbazonato) copper complexes, glyoxalbis[N4-methylthiosemicarbazonato]Cu(II) [Cu(II)(gtsm)] and diacetylbis[N4-methylthiosemicarbazonato]Cu(II) [Cu(II)(atsm)], for the treatment of prostate cancer was assessed in cell culture and animal models. Distinctively, copper dissociates intracellularly from Cu(II)(gtsm) but is retained by Cu(II)(atsm). We further demonstrated that intracellular H2gtsm [reduced Cu(II)(gtsm)] continues to redistribute copper into a bioavailable (exchangeable) pool. Both Cu(II)(gtsm) and Cu(II)(atsm) selectively kill transformed (hyperplastic and carcinoma) prostate cell lines but, importantly, do not affect the viability of primary prostate epithelial cells. Increasing extracellular copper concentrations enhanced the therapeutic capacity of both Cu(II)(gtsm) and Cu(II)(atsm), and their ligands (H2gtsm and H2atsm) were toxic only toward cancerous prostate cells when combined with copper. Treatment of the Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) model with Cu(II)(gtsm) (2.5 mg/kg) significantly reduced prostate cancer burden (∼70%) and severity (grade), while treatment with Cu(II)(atsm) (30 mg/kg) was ineffective at the given dose. However, Cu(II)(gtsm) caused mild kidney toxicity in the mice, associated primarily with interstitial nephritis and luminal distention. Mechanistically, we demonstrated that Cu(II)(gtsm) inhibits proteasomal chymotrypsin-like activity, a feature further established as being common to copper-ionophores that increase intracellular bioavailable copper. We have demonstrated that increasing intracellular bioavailable copper can selectively kill cancerous prostate cells in vitro and in vivo and have revealed the potential for bis(thiosemicarbazone) copper complexes to be developed as therapeutics for prostate cancer.

  5. Mechanism of Action of Two Flavone Isomers Targeting Cancer Cells with Varying Cell Differentiation Status.

    Directory of Open Access Journals (Sweden)

    Timothy M LeJeune

    Full Text Available Apoptosis can be triggered in two different ways, through the intrinsic or the extrinsic pathway. The intrinsic pathway is mediated by the mitochondria via the release of cytochrome C while the extrinsic pathway is prompted by death receptor signals and bypasses the mitochondria. These two pathways are closely related to cell proliferation and survival signaling cascades, which thereby constitute possible targets for cancer therapy. In previous studies we introduced two plant derived isomeric flavonoids, flavone A and flavone B which induce apoptosis in highly tumorigenic cancer cells of the breast, colon, pancreas, and the prostate. Flavone A displayed potent cytotoxic activity against more differentiated carcinomas of the colon (CaCo-2 and the pancreas (Panc28, whereas flavone B cytotoxic action is observed on poorly differentiated carcinomas of the colon (HCT 116 and pancreas (MIA PaCa. Apoptosis is induced by flavone A in better differentiated colon cancer CaCo-2 and pancreatic cancer Panc 28 cells via the intrinsic pathway by the inhibition of the activated forms of extracellular signal-regulated kinase (ERK and pS6, and subsequent loss of phosphorylation of Bcl-2 associated death promoter (BAD protein, while apoptosis is triggered by flavone B in poorly differentiated colon cancer HCT 116 and MIA PaCa pancreatic cancer cells through the extrinsic pathway with the concomitant upregulation of the phosphorylated forms of ERK and c-JUN at serine 73. These changes in protein levels ultimately lead to activation of apoptosis, without the involvement of AKT.

  6. DNA-templated antibody conjugation for targeted drug delivery to cancer cells

    DEFF Research Database (Denmark)

    Liu, Tianqiang

    2016-01-01

    -templated organic synthesis due to the wide existence of the 3-histidine cluster in most wild-type proteins. In this thesis, three projects that relate to targeted drug delivery to cancer cells based on the DTPC method is described. The first project was a delivery system which uses transferrin as the targeting...... ligand and saporin (ribosome inactivating protein) as the warhead to achieve enhanced cellular uptake and cytotoxicity of saporin to transferrin receptor overexpressed cancer cell line. The transferrin-saporin conjugate complex are formed by linking the site-selective DNA-transferrin conjugates with mono...... to cancer cells. The DNA duplex in the conjugates could be used for doxorubicin intercalation since it contains CGA repeats. Confocal microscopy and flow cytometry results showed a receptor-mediated targeting manner to EGFR+ cancer cell lines (KB and MDA-MB-231), and resulted in enhanced cell killing...

  7. Keratin 15 promoter targets putative epithelial stem cells in the hair follicle bulge.

    Science.gov (United States)

    Liu, Yaping; Lyle, Stephen; Yang, Zaixin; Cotsarelis, George

    2003-11-01

    Putative epithelial stem cells in the hair follicle bulge are thought to play pivotal roles in the homeostasis, aging, and carcinogenesis of the cutaneous epithelium. Elucidating the role of bulge cells in these processes has been hampered by the lack of gene promoters that target this area with specificity. Here we describe the isolation of the mouse keratin 15 (K15) promoter and demonstrate its utility for preferentially targeting hair follicle bulge cells in adult K15/lacZ transgenic mice. We found that patterns of K15 expression and promoter activity changed with age and correlated with levels of differentiation within the cutaneous epithelium; less differentiated keratinocytes in the epidermis of the neonatal mouse and in the bulge area of the adult mouse preferentially expressed K15. These findings demonstrate the utility of the K15 promoter for targeting epithelial stem cells in the hair follicle bulge and set the stage for elucidating the role of bulge cells in skin biology.

  8. miR-1271 promotes non-small-cell lung cancer cell proliferation and invasion via targeting HOXA5

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yongfang; Xu, Lianhong; Jiang, Lixin, E-mail: jianglx66766@163.com

    2015-03-13

    MicroRNAs (miRNAs) are short, non-coding RNAs (∼22 nt) that play important roles in the pathogenesis of human diseases by negatively regulating numerous target genes at posttranscriptional level. However, the role of microRNAs in lung cancer, particularly non-small-cell lung cancer (NSCLC), has remained elusive. In this study, two microRNAs, miR-1271 and miR-628, and their predicted target genes were identified differentially expressed in NSCLC by analyzing the miRNA and mRNA expression data from NSCLC tissues and their matching normal controls. miR-1271 and its target gene HOXA5 were selected for further investigation. CCK-8 proliferation assay showed that the cell proliferation was promoted by miR-1271 in NSCLC cells, while miR-1271 inhibitor could significantly inhibited the proliferation of NSCLC cells. Interestingly, migration and invasion assay indicated that overexpression of miR-1271 could significantly promoted the migration and invasion of NSCLC cells, whereas miR-1271 inhibitor could inhibited both cell migration and invasion of NSCLC cells. Western blot showed that miR-1271 suppressed the protein level of HOXA5, and luciferase assays confirmed that miR-1271 directly bound to the 3'untranslated region of HOXA5. This study indicated indicate that miR-1271 regulates NSCLC cell proliferation and invasion, via the down-regulation of HOXA5. Thus, miR-1271 may represent a potential therapeutic target for NSCLC intervention. - Highlights: • Overexpression of miR-1271 promoted proliferation and invasion of NSCLC cells. • miR-1271 inhibitor inhibited the proliferation and invasion of NSCLC cells. • miR-1271 targets 3′ UTR of HOXA5 in NSCLC cells. • miR-1271 negatively regulates HOXA5 in NSCLC cells.

  9. An off-target nucleostemin RNAi inhibits growth in human glioblastoma-derived cancer stem cells.

    Directory of Open Access Journals (Sweden)

    Jon Gil-Ranedo

    Full Text Available Glioblastomas (GBM may contain a variable proportion of active cancer stem cells (CSCs capable of self-renewal, of aggregating into CD133(+ neurospheres, and to develop intracranial tumors that phenocopy the original ones. We hypothesized that nucleostemin may contribute to cancer stem cell biology as these cells share characteristics with normal stem cells. Here we report that nucleostemin is expressed in GBM-CSCs isolated from patient samples, and that its expression, conversely to what it has been described for ordinary stem cells, does not disappear when cells are differentiated. The significance of nucleostemin expression in CSCs was addressed by targeting the corresponding mRNA using lentivirally transduced short hairpin RNA (shRNA. In doing so, we found an off-target nucleostemin RNAi (shRNA22 that abolishes proliferation and induces apoptosis in GBM-CSCs. Furthermore, in the presence of shRNA22, GBM-CSCs failed to form neurospheres in vitro or grow on soft agar. When these cells are xenotransplanted into the brains of nude rats, tumor development is significantly delayed. Attempts were made to identify the primary target/s of shRNA22, suggesting a transcription factor involved in one of the MAP-kinases signaling-pathways or multiple targets. The use of this shRNA may contribute to develop new therapeutic approaches for this incurable type of brain tumor.

  10. ALK signaling and target therapy in anaplastic large cell lymphoma

    Directory of Open Access Journals (Sweden)

    Fabrizio eTabbo

    2012-05-01

    Full Text Available The discovery by Morris SW et al. in 1994 of the genes contributing to the t(2;5(p23;q35 translocation has put the foundation for a molecular based recognition of Anaplastic Large Cell Lymphoma (ALCL and pointed out the need for a further stratification of T-cell neoplasia. Likewise the detection of ALK genetic lesions among many human cancers has defined unique subsets of cancer patients, providing new opportunities for innovative therapeutic interventions. The objective of this review is to appraise the molecular mechanisms driving ALK-mediated transformation, and to maintain the neoplastic phenotype. The understanding of these events will allow the design and implementation of novel tailored strategies for a well-defined subset of cancer patients.

  11. Histone modifications: Targeting head and neck cancer stem cells

    Institute of Scientific and Technical Information of China (English)

    John; M; Le; Cristiane; H; Squarize; Rogerio; M; Castilho

    2014-01-01

    Head and neck squamous cell carcinoma(HNSCC) is the sixth most common cancer worldwide, and is responsible for a quarter of a million deaths annually. The survival rate for HNSCC patients is poor, showing only minor improvement in the last three decades. Despite new surgical techniques and chemotherapy protocols, tumor resistance to chemotherapy remains a significant challenge for HNSCC patients. Numerous mechanisms underlie chemoresistance, including genetic and epigenetic alterations in cancer cells that may be acquired during treatment and activation of mitogenic signaling pathways, such as nuclear factor kappa-light-chain-enhancer-of activated B cell, that cause reduced apoptosis. In addition to dysfunctional molecular signaling, emerging evidence reveals involvement of cancer stem cells(CSCs) in tumor development and in tumor resistance to chemotherapy and radiotherapy. These observations have sparked interest in understanding the mechanisms involved in the control of CSC function and fate. Post-translational modifications of histones dynamically influence gene expression independent of alterations to the DNA sequence. Recent findings from our group have shown that pharmacological induction of posttranslational modifications of tumor histones dynamically modulates CSC plasticity. These findings suggest that a better understanding of the biology of CSCs in response to epigenetic switches and pharmacological inhibitors of histone function may directly translate to the development of a mechanism-based strategy to disrupt CSCs. In this review, we present and discuss current knowledge on epigenetic modifications of HNSCC and CSC response to DNA methylation and histone modifications. In addition, we discuss chromatin modifications and their role in tumor resistance to therapy.

  12. Isoform-specific targeting of ROCK proteins in immune cells

    OpenAIRE

    Zanin-Zhorov, Alexandra; Flynn, Ryan; Waksal, Samuel D.; Blazar, Bruce R.

    2016-01-01

    ABSTRACT Rho-associated kinase 1 (ROCK1) and ROCK2 are activated by Rho GTPase and control cytoskeleton rearrangement through modulating the phosphorylation of their down-stream effector molecules. Although these 2 isoforms share more than 90% homology within their kinase domain the question of whether ROCK proteins function identically in different cell types is not clear. By using both pharmacological inhibition and genetic knockdown approaches recent studies suggest that the ROCK2 isoform ...

  13. Targeting Protective Autophagy Exacerbates UV-Triggered Apoptotic Cell Death

    Directory of Open Access Journals (Sweden)

    Shih-Hwa Chiou

    2012-01-01

    Full Text Available Autophagy is activated by various stresses, including DNA damage, and previous studies of DNA damage-induced autophagy have focused on the response to chemotherapeutic drugs, ionizing radiation, and reactive oxygen species. In this study, we investigated the biological significance of autophagic response to ultraviolet (UV irradiation in A549 and H1299 cells. Our results indicated that UV induces on-rate autophagic flux in these cells. Autophagy inhibition resulting from the knockdown of beclin-1 and Atg5 reduced cell viability and enhanced apoptosis. Moreover, we found that ATR phosphorylation was accompanied by microtubule-associated protein 1 light chain 3B II (LC3B-II expression during the early phases following UV irradiation, which is a well-established inducer of ATR. Knocking down ATR further attenuated the reduction in LC3B-II at early stages in response to UV treatment. Despite the potential role of ATR in autophagic response, reduced ATR expression does not affect autophagy induction during late phases (24 and 48 h after UV treatment. The result is consistent with the reduced ATR phosphorylation at the same time points and suggests that autophagic response at this stage is activated via a distinct pathway. In conclusion, this study demonstrated that autophagy acts as a cytoprotective mechanism against UV-induced apoptosis and that autophagy induction accompanied with apoptosis at late stages is independent of ATR activation.

  14. Hyperinsulinism induced by targeted suppression of beta cell KATP channels.

    Science.gov (United States)

    Koster, J C; Remedi, M S; Flagg, T P; Johnson, J D; Markova, K P; Marshall, B A; Nichols, C G

    2002-12-24

    ATP-sensitive K+ (K(ATP)) channels couple cell metabolism to electrical activity. To probe the role of K(ATP) in glucose-induced insulin secretion, we have generated transgenic mice expressing a dominant-negative, GFP-tagged K(ATP) channel subunit in which residues 132-134 (Gly-Tyr-Gly) in the selectivity filter were replaced by Ala-Ala-Ala, under control of the insulin promoter. Transgene expression was confirmed by both beta cell-specific green fluorescence and complete suppression of channel activity in those cells ( approximately 70%) that did fluoresce. Transgenic mice developed normally with no increased mortality and displayed normal body weight, blood glucose levels, and islet architecture. However, hyperinsulinism was evident in adult mice as (i) a disproportionately high level of circulating serum insulin for a given glucose concentration ( approximately 2-fold increase in blood insulin), (ii) enhanced glucose-induced insulin release from isolated islets, and (iii) mild yet significant enhancement in glucose tolerance. Enhanced glucose-induced insulin secretion results from both increased glucose sensitivity and increased release at saturating glucose concentration. The results suggest that incomplete suppression of K(ATP) channel activity can give rise to a maintained hyperinsulinism.

  15. Intracellular protein target detection by quantum dots optimized for live cell imaging.

    Science.gov (United States)

    Choi, Youngseon; Kim, Keumhyun; Hong, Sukmin; Kim, Hichul; Kwon, Yong-Jun; Song, Rita

    2011-08-17

    Imaging of specific intracellular target proteins in living cells has been of great challenge and importance for understanding intracellular events and elucidating various biological phenomena. Highly photoluminescent and water-soluble semiconductor nanocrystal quantum dots (QDs) have been extensively applied to various cellular imaging applications due to the long-term photostability and the tunable narrow emission spectra with broad excitation. Despite the great success of various bioimaging and diagnostic applications, visualization of intracellular targets in live cells still has been of great challenge. Nonspecific binding, difficulty of intracellular delivery, or endosomal trapping of nanosized QDs are the main reasons to hamper specific target binding in live cells. In this context, we prepared the polymer-coated QDs (pcQD) of which the surface was optimized for specific intracellular targeting in live cells. Efficient intracellular delivery was achieved through PEGylation and subsequent cell penetrating peptide (i.e., TAT) conjugation to the pcQD in order to avoid significant endosomal sequestration and to facilitate internalization of the QDs, respectively. In this study, we employed HEK293 cell line overexpressing endothelin A receptor (ET(A)R), a family of G-protein coupled receptor (GPCR), of which the cytosolic c-terminal site is genetically engineered to possess green fluorescent protein (GFP) as our intracellular protein target. The fluorescence signal of the target protein and the well-defined intracellular behavior of the GPCR help to evaluate the targeting specificity of QDs in living cells. To test the hypothesis that the TAT-QDs conjugated with antibody against intracellular target of interest can find the target, we conjugated anti-GFP antibody to TAT-PEG-pcQD using heterobifunctional linkers. Compared to the TAT-PEG-pcQD, which was distributed throughout the cytoplasm, the antiGFP-functionalized TAT-PEG-pcQD could penetrate the cell membrane

  16. 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.

  17. MicroRNA-145 targets YES and STAT1 in colon cancer cells

    DEFF Research Database (Denmark)

    Gregersen, Lea H; Jacobsen, Anders B; Frankel, Lisa

    2010-01-01

    miRNA overexpression. Gene Ontology analysis showed an overrepresentation of genes involved in cell death, cellular growth and proliferation, cell cycle, gene expression and cancer. A number of the identified miRNA targets have previously been implicated in cancer, including YES, FSCN1, ADAM17, BIRC2......, VANGL1 as well as the transcription factor STAT1. Both YES and STAT1 were verified as direct miR-145 targets. CONCLUSIONS/SIGNIFICANCE: The study identifies and validates new cancer-relevant direct targets of miR-145 in colon cancer cells and hereby adds important mechanistic understanding of the tumor......BACKGROUND: MicroRNAs (miRNAs) have emerged as important gene regulators and are recognized as key players in tumorigenesis. miR-145 is reported to be down-regulated in several cancers, but knowledge of its targets in colon cancer remains limited. METHODOLOGY/PRINCIPAL FINDINGS: To investigate...

  18. Development of an efficient targeted cell-SELEX procedure for DNA aptamer reagents.

    Directory of Open Access Journals (Sweden)

    Susanne Meyer

    Full Text Available BACKGROUND: DNA aptamers generated by cell-SELEX offer an attractive alternative to antibodies, but generating aptamers to specific, known membrane protein targets has proven challenging, and has severely limited the use of aptamers as affinity reagents for cell identification and purification. METHODOLOGY: We modified the BJAB lymphoblastoma cell line to over-express the murine c-kit cell surface receptor. After six rounds of cell-SELEX, high-throughput sequencing and bioinformatics analysis, we identified aptamers that bound BJAB cells expressing c-kit but not wild-type BJAB controls. One of these aptamers also recognizes c-kit endogenously expressed by a mast cell line or hematopoietic progenitor cells, and specifically blocks binding of the c-kit ligand stem cell factor (SCF. This aptamer enables better separation by fluorescence-activated cell sorting (FACS of c-kit(+ hematopoietic progenitor cells from mixed bone marrow populations than a commercially available antibody, suggesting that this approach may be broadly useful for rapid isolation of affinity reagents suitable for purification of other specific cell types. CONCLUSIONS/SIGNIFICANCE: Here we describe a novel procedure for the efficient generation of DNA aptamers that bind to specific cell membrane proteins and can be used as high affinity reagents. We have named the procedure STACS (Specific TArget Cell-SELEX.

  19. Targeting the gut vascular endothelium induces gut effector CD8 T cell responses via cross-presentation by dendritic cells.

    Science.gov (United States)

    Bourges, Dorothee; Zhan, Yifan; Brady, Jamie L; Braley, Hal; Caminschi, Irina; Prato, Sandro; Villadangos, José A; Lew, Andrew M

    2007-11-01

    Systemic delivery of Ag usually induces poor mucosal immunity. To improve the CD8 T cell response at mucosal sites, we targeted the Ag to MAdCAM-1, a mucosal addressin cell adhesion molecule expressed mainly by high endothelial venules (HEV) in mesenteric lymph nodes (MLN) and Peyer's patches of gut-associated lymphoid tissue. When chemical conjugates of anti-MAdCAM-1 Ab and model Ag OVA were injected i.v., a greatly enhanced proliferative response of Ag-specific OT-I CD8 T cells was detected in MLN. This was preceded by prolonged accumulation, up to 2 wk, of the anti-MAdCAM OVA conjugate on HEV of Peyer's patches and MLN. In contrast, nontargeted OVA conjugate was very inefficient in inducing OT-I CD8 T cell proliferation in MLN and required at least 20-fold more Ag to induce a comparable response. In addition, MAdCAM targeting elicits an endogenous OVA-specific CD8 T cell response, evident by IFN-gamma production and target killing. Induced response offers protection against an OVA-expressing B cell lymphoma. We propose that the augmentation of gut CD8 T cell responses by MAdCAM targeting is due to both accumulation of Ag in the HEV and conversion of a soluble Ag to a cell-associated one, allowing cross-presentation by DCs.

  20. Transfection and mutagenesis of target genes in mosquito cells by locked nucleic acid-modified oligonucleotides.

    Science.gov (United States)

    Pakpour, Nazzy; Cheung, Kong Wai; Souvannaseng, Lattha; Concordet, Jean-Paul; Luckhart, Shirley

    2010-12-26

    Plasmodium parasites, the causative agent of malaria, are transmitted through the bites of infected Anopheles mosquitoes resulting in over 250 million new infections each year. Despite decades of research, there is still no vaccine against malaria, highlighting the need for novel control strategies. One innovative approach is the use of genetically modified mosquitoes to effectively control malaria parasite transmission. Deliberate alterations of cell signaling pathways in the mosquito, via targeted mutagenesis, have been found to regulate parasite development (1). From these studies, we can begin to identify potential gene targets for transformation. Targeted mutagenesis has traditionally relied upon the homologous recombination between a target gene and a large DNA molecule. However, the construction and use of such complex DNA molecules for generation of stably transformed cell lines is costly, time consuming and often inefficient. Therefore, a strategy using locked nucleic acid-modified oligonucleotides (LNA-ONs) provides a useful alternative for introducing artificial single nucleotide substitutions into episomal and chromosomal DNA gene targets (reviewed in (2)). LNA-ON-mediated targeted mutagenesis has been used to introduce point mutations into genes of interest in cultured cells of both yeast and mice (3,4). We show here that LNA-ONs can be used to introduce a single nucleotide change in a transfected episomal target that results in a switch from blue fluorescent protein (BFP) expression to green fluorescent protein (GFP) expression in both Anopheles gambiae and Anopheles stephensi cells. This conversion demonstrates for the first time that effective mutagenesis of target genes in mosquito cells can be mediated by LNA-ONs and suggests that this technique may be applicable to mutagenesis of chromosomal targets in vitro and in vivo.

  1. MicroRNA-944 Affects Cell Growth by Targeting EPHA7 in Non-Small Cell Lung Cancer

    Science.gov (United States)

    Liu, Minxia; Zhou, Kecheng; Cao, Yi

    2016-01-01

    MicroRNAs (miRNAs) have critical roles in lung tumorigenesis and development. To determine aberrantly expressed miRNAs involved in non-small cell lung cancer (NSCLC) and investigate pathophysiological functions and mechanisms, we firstly carried out small RNA deep sequencing in NSCLC cell lines (EPLC-32M1, A549 and 801D) and a human immortalized cell line 16HBE, we then studied miRNA function by cell proliferation and apoptosis. cDNA microarray, luciferase reporter assay and miRNA transfection were used to investigate interaction between the miRNA and target gene. miR-944 was significantly down-regulated in NSCLC and had many putative targets. Moreover, the forced expression of miR-944 significantly inhibited the proliferation of NSCLC cells in vitro. By integrating mRNA expression data and miR-944-target prediction, we disclosed that EPHA7 was a potential target of miR-944, which was further verified by luciferase reporter assay and microRNA transfection. Our data indicated that miR-944 targets EPHA7 in NSCLC and regulates NSCLC cell proliferation, which may offer a new mechanism underlying the development and progression of NSCLC. PMID:27681722

  2. Preclinical targeting of human T-cell malignancies using CD4-specific chimeric antigen receptor (CAR)-engineered T cells.

    Science.gov (United States)

    Pinz, K; Liu, H; Golightly, M; Jares, A; Lan, F; Zieve, G W; Hagag, N; Schuster, M; Firor, A E; Jiang, X; Ma, Y

    2016-03-01

    Peripheral T-cell lymphomas (PTCLs) are aggressive lymphomas with no effective upfront standard treatment and ineffective options in relapsed disease, resulting in poorer clinical outcomes as compared with B-cell lymphomas. The adoptive transfer of T cells engineered to express chimeric antigen receptors (CARs) is a promising new approach for treatment of hematological malignancies. However, preclinical reports of targeting T-cell lymphoma with CARs are almost non-existent. Here we have designed a CAR, CD4CAR, which redirects the antigen specificity of CD8+ cytotoxic T cells to CD4-expressing cells. CD4CAR T cells derived from human peripheral blood mononuclear cells and cord blood effectively redirected T-cell specificity against CD4+ cells in vitro. CD4CAR T cells efficiently eliminated a CD4+ leukemic cell line and primary CD4+ PTCL patient samples in co-culture assays. Notably, CD4CAR T cells maintained a central memory stem cell-like phenotype (CD8+CD45RO+CD62L+) under standard culture conditions. Furthermore, in aggressive orthotropic T-cell lymphoma models, CD4CAR T cells efficiently suppressed the growth of lymphoma cells while also significantly prolonging mouse survival. Combined, these studies demonstrate that CD4CAR-expressing CD8+ T cells are efficacious in ablating malignant CD4+ populations, with potential use as a bridge to transplant or stand-alone therapy for the treatment of PTCLs.

  3. Odin (ANKS1A is a Src family kinase target in colorectal cancer cells

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    Feller Stephan M

    2008-10-01

    Full Text Available Abstract Background Src family kinases (SFK are implicated in the development of some colorectal cancers (CRC. One SFK member, Lck, is not detectable in normal colonic epithelium, but becomes aberrantly expressed in a subset of CRCs. Although SFK have been extensively studied in fibroblasts and different types of immune cells, their physical and functional targets in many epithelial cancers remain poorly characterised. Results 64 CRC cell lines were tested for expression of Lck. SW620 CRC cells, which express high levels of Lck and also contain high basal levels of tyrosine phosphorylated (pY proteins, were then analysed to identify novel SFK targets. Since SH2 domains of SFK are known to often bind substrates after phosphorylation by the kinase domain, the LckSH2 was compared with 14 other SH2s for suitability as affinity chromatography reagent. Mass spectrometric analyses of LckSH2-purified pY proteins subsequently identified several proteins readily known as SFK kinase substrates, including cortactin, Tom1L1 (SRCASM, GIT1, vimentin and AFAP1L2 (XB130. Additional proteins previously reported as substrates of other tyrosine kinase were also detected, including the EGF and PDGF receptor target Odin. Odin was further analysed and found to contain substantially less pY upon inhibition of SFK activity in SW620 cells, indicating that it is a formerly unknown SFK target in CRC cells. Conclusion Rapid identification of known and novel SFK targets in CRC cells is feasible with SH2 domain affinity chromatography. The elucidation of new SFK targets like Odin in epithelial cancer cells is expected to lead to novel insight into cancer cell signalling mechanisms and may also serve to indicate new biomarkers for monitoring tumor cell responses to drug treatments.

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

    Science.gov (United States)

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

    2017-01-01

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

  5. MicroRNA-145 targets YES and STAT1 in colon cancer cells

    DEFF Research Database (Denmark)

    Gregersen, Lea H; Jacobsen, Anders B; Frankel, Lisa;

    2010-01-01

    miRNA overexpression. Gene Ontology analysis showed an overrepresentation of genes involved in cell death, cellular growth and proliferation, cell cycle, gene expression and cancer. A number of the identified miRNA targets have previously been implicated in cancer, including YES, FSCN1, ADAM17, BIRC2...

  6. Amidine-bearing lipoplex targeting to hepatocyte cells

    Institute of Scientific and Technical Information of China (English)

    Yasuya Kudo; Kazunori Koiwai; Kazuhiro Shimizu; Shota Kusuki; Mina Sakuragi; Naohiko Shimada; Yoichi Takeda; Kazuo Sakurai

    2008-01-01

    A lipoplex (i.e., pDNA#1/lipid complex and transfection reagent for pDNA delivery) containing galactosylceramide (GalCer) and an amidine-bearing lipid (TRX) was examined whether the bound pDNA was specifically ingested by hepatocyte via asialoglycoprotein receptor (ASGPR) and then expressed protein. Gel electrophoresis and small-angle X-ray scattering (SAXS) confirmed that the TRX-GalCer liposome#2 complexed with pDNA and the resultant lipoplex took a hexagonally packed inverted cylinder structure when the GalCer composition was less than 20 wt.% of the total lipid. When the lipoplex carrying pGL3 (luciferase-cording pDNA) was administrated to HepG2, the luciferase activity was increased with increasing the GalCer composition until it reached 3 wt.% and then decreased upon further addition of GalCer. When we added galactose itself as a competitor, the luciferase activity was decreased, while glucose did not show such decrease, suggesting that HepG2 ingested the lipoplex via ASGPR-mediated endocytosis. This paper indicated that the hexagonally packed inverted cylinder structures of lipoplex may not always provide excellent transfection and presented a possibility that the TRX lipoplex#3 can obtain a cellular-targeting ability through the receptors for oligosaccharide.

  7. Epidermal Growth Factor Receptor targeting in non-small cell lung cancer: revisiting different strategies against the same target.

    Science.gov (United States)

    Castañón, Eduardo; Martín, Patricia; Rolfo, Christian; Fusco, Juan P; Ceniceros, Lucía; Legaspi, Jairo; Santisteban, Marta; Gil-Bazo, Ignacio

    2014-01-01

    Epidermal Growth Factor Receptor (EGFR) tyrosine kinase inhibitors (TKIs) have changed the paradigm of treatment in non-small cell lung cancer (NSCLC). The molecular biology study of EGFR has led to clinical trials that select patients more accurately, regarding the presence of EGFR activating mutations. Nonetheless, a lack of response or a temporary condition of the response has been detected in patients on EGFR TKIs. This has urged to study potential resistance mechanisms underneath. The most important ones are the presence of secondary mutations in EGFR, such as T790M, or the overexpression of mesenchymal-epithelial transition factor (MET) that may explain why patients who initially respond to EGFR TKIs, may ultimately become refractory. Several approaches have been taken and new drugs both targeting EGFR resistance-mutation or MET are currently being developed. Here we review and update the EGFR biological pathway as well as the clinical data leading to approval of the EGFR TKIs currently in the market. New compounds under investigation targeting resistance mutations or dually targeting EGFR and other relevant receptors are also reviewed and discussed.

  8. Targeting CXCR4 in HIV Cell-Entry Inhibition

    DEFF Research Database (Denmark)

    Steen, Anne; Schwartz, T W; Rosenkilde, M M

    2010-01-01

    CXCR4 and CCR5 constitute the two major coreceptors for HIV-1 entry into host cells. In the course of an HIV-infection, a coreceptor switch takes place in approximately half of the patients - from R5 HIV-1 (CCR5 utilizing) strains to X4 HIV-1 (CXCR4 utilizing) strains. Treatment of HIV......-infected individuals with CXCR4 antagonists delays the onset of AIDS by preventing the CCR5 to CXCR4 coreceptor switch. In addition to the endogenous CXCR4 and CCR5 ligands, other chemokines, for example the human herpesvirus 8 encoded CC-chemokine, vCCL2, and modifications hereof, have proven efficient HIV-1 cell...... no oral bioavailability. The hunt for orally active small-molecule CXCR4 antagonists led to the development of monocyclam-based compounds, and recently to the non-cyclam antagonist AMD070, which is orally active and currently in Phase II clinical trial as anti-HIV treatment. Current review provides...

  9. Recent advances of novel targeted therapy for squamous cell carcinoma of the head and neck

    Directory of Open Access Journals (Sweden)

    Jed A. Katzel

    2011-12-01

    Full Text Available Targeted therapies have proven beneficial for patients suffering from a number of different malignancies, including cancers of the head and neck. Cetuximab, a monoclonal antibody targeting the epidermal growth factor receptor has shown benefit in combination with radiation for untreated patients or as a single agent for patients with platinum resistant disease. Cetuximab is the only targeted agent currently approved by the Federal Drug Administration for the treatment of head and neck cancer. A number of other agents have shown promising initial results including intracellular tyrosine kinase inhibitors, agents targeting vascular endothelial growth factor receptor, as well as other classes of novel therapies. Some of the data supporting the use of targeted therapy, including agents not yet approved in head and neck cancer, will be presented in this review. As our understanding of the cancer cell signaling pathways and novel targeted agents increases, the potential for treatment with reduced toxicity and improved clinical outcomes will become a reality.

  10. AS1411 aptamer tagged PLGA-lecithin-PEG nanoparticles for tumor cell targeting and drug delivery.

    Science.gov (United States)

    Aravind, Athulya; Jeyamohan, Prashanti; Nair, Remya; Veeranarayanan, Srivani; Nagaoka, Yutaka; Yoshida, Yasuhiko; Maekawa, Toru; Kumar, D Sakthi

    2012-11-01

    Liposomes and polymers are widely used drug carriers for controlled release since they offer many advantages like increased treatment effectiveness, reduced toxicity and are of biodegradable nature. In this work, anticancer drug-loaded PLGA-lecithin-PEG nanoparticles (NPs) were synthesized and were functionalized with AS1411 anti-nucleolin aptamers for site-specific targeting against tumor cells which over expresses nucleolin receptors. The particles were characterized by transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). The drug-loading efficiency, encapsulation efficiency and in vitro drug release studies were conducted using UV spectroscopy. Cytotoxicity studies were carried out in two different cancer cell lines, MCF-7 and GI-1 cells and two different normal cells, L929 cells and HMEC cells. Confocal microscopy and flowcytometry confirmed the cellular uptake of particles and targeted drug delivery. The morphology analysis of the NPs proved that the particles were smooth and spherical in shape with a size ranging from 60 to 110 nm. Drug-loading studies indicated that under the same drug loading, the aptamer-targeted NPs show enhanced cancer killing effect compared to the corresponding non-targeted NPs. In addition, the PLGA-lecithin-PEG NPs exhibited high encapsulation efficiency and superior sustained drug release than the drug loaded in plain PLGA NPs. The results confirmed that AS1411 aptamer-PLGA-lecithin-PEG NPs are potential carrier candidates for differential targeted drug delivery.

  11. From drug response profiling to target addiction scoring in cancer cell models

    Directory of Open Access Journals (Sweden)

    Bhagwan Yadav

    2015-10-01

    Full Text Available Deconvoluting the molecular target signals behind observed drug response phenotypes is an important part of phenotype-based drug discovery and repurposing efforts. We demonstrate here how our network-based deconvolution approach, named target addiction score (TAS, provides insights into the functional importance of druggable protein targets in cell-based drug sensitivity testing experiments. Using cancer cell line profiling data sets, we constructed a functional classification across 107 cancer cell models, based on their common and unique target addiction signatures. The pan-cancer addiction correlations could not be explained by the tissue of origin, and only correlated in part with molecular and genomic signatures of the heterogeneous cancer cells. The TAS-based cancer cell classification was also shown to be robust to drug response data resampling, as well as predictive of the transcriptomic patterns in an independent set of cancer cells that shared similar addiction signatures with the 107 cancers. The critical protein targets identified by the integrated approach were also shown to have clinically relevant mutation frequencies in patients with various cancer subtypes, including not only well-established pan-cancer genes, such as PTEN tumor suppressor, but also a number of targets that are less frequently mutated in specific cancer types, including ABL1 oncoprotein in acute myeloid leukemia. An application to leukemia patient primary cell models demonstrated how the target deconvolution approach offers functional insights into patient-specific addiction patterns, such as those indicative of their receptor-type tyrosine-protein kinase FLT3 internal tandem duplication (FLT3-ITD status and co-addiction partners, which may lead to clinically actionable, personalized drug treatment developments. To promote its application to the future drug testing studies, we have made available an open-source implementation of the TAS calculation in the form

  12. A novel method for producing target cells and assessing cytotoxic T lymphocyte activity in outbred hosts

    Directory of Open Access Journals (Sweden)

    Bendinelli Mauro

    2009-03-01

    Full Text Available Abstract Background Cytotoxic T lymphocytes play a crucial role in the immunological control of microbial infections and in the design of vaccines and immunotherapies. Measurement of cytotoxic T lymphocyte activity requires that the test antigen is presented by target cells having the same or compatible class I major hystocompatibility complex antigens as the effector cells. Conventional assays use target cells labeled with 51chromium and infer cytotoxic T lymphocyte activity by measuring the isotope released by the target cells lysed following incubation with antigen-specific cytotoxic T lymphocytes. This assay is sensitive but needs manipulation and disposal of hazardous radioactive reagents and provides a bulk estimate of the reporter released, which may be influenced by spontaneous release of the label and other poorly controllable variables. Here we describe a novel method for producing target in outbred hosts and assessing cytotoxic T lymphocyte activity by flow cytometry. Results The method consists of culturing skin fibroblasts, immortalizing them with a replication defective clone of simian virus 40, and finally transducing them with a bicistronic vector encoding the target antigen and the reporter green fluorescent protein. When used in a flow cytometry-based assay, the target cells obtained with this method proved valuable for assessing the viral envelope protein specific cytotoxic T lymphocyte activity in domestic cats acutely or chronically infected with feline immunodeficiency virus, a lentivirus similar to human immunodeficiency virus and used as animal model for AIDS studies. Conclusion Given the versatility of the bicistronic vector used, its ability to deliver multiple and large transgenes in target cells, and its extremely wide cell specificity when pseudotyped with the vesicular stomatitis virus envelope protein, the method is potentially exploitable in many animal species.

  13. Multifunctional AS1411-functionalized fluorescent gold nanoparticles for targeted cancer cell imaging and efficient photodynamic therapy.

    Science.gov (United States)

    Ai, Jun; Xu, Yuanhong; Lou, Baohua; Li, Dan; Wang, Erkang

    2014-01-01

    Herein, one multifunctional AS1411-functionalized fluorescent gold nanoparticles (named NAANPs) is synthesized and successfully applied for both targeted cancer cell imaging and efficient photodynamic therapy (PDT). The NAANPs are obtained by functionalizing the gold nanoparticles with AS1411 aptamer and then bound with one porphyrin derivative N-methylmesoporphyrin IX (NMM). Using HeLa cells over expressing nucleolin as representative cancer cells, the formed NAANPs can target to the cell surface via the specific AS1411-nucleolin interaction, which can discriminate the cancer cells from normal ones (e.g. HEK293) unambiguously. That the fluorescence intensity of NMM increased significantly upon binding to AS1411 G-quadruplex makes the NAANPs appropriate fluorescence reagent for cell imaging. Meanwhile, NMM can also be used as a photosensitizer, thus irradiation of the NAANPs by the white light from a common electric torch can lead to efficient production of cytotoxic reactive oxygen species for establishing a new type of PDT to cancer cells. Gold nanoparticles play the roles of both carrier and enhancer of the functional groups onto the cells. In addition, they not only possess inherently certain cytotoxicity to the cancer cells, but also boost the cellular uptake of the fluorescent groups. As a result, the efficiency of both the targeted cell imaging and PDT could be ensured.

  14. Targeting NK cells for anti-cancer immunotherapy: clinical and pre-clinical approaches

    Directory of Open Access Journals (Sweden)

    Sebastian eCarotta

    2016-04-01

    Full Text Available The recent success of checkpoint blockade has highlighted the potential of immunotherapy approaches for cancer treatment. While the majority of approved immunotherapy drugs target T cell subsets, it is appreciated that other components of the immune system have important roles in tumor immune-surveillance as well and thus represent promising additional targets for immunotherapy. Natural killer cells are the body’s first line of defense against infected or transformed cells as they kill target cells in an antigen-independent manner. Although several studies have clearly demonstrated the active role of NK cells in cancer-immune surveillance, only few clinically approved therapies currently exist that harness their potential. Our increased understanding of NK cell biology over the past few years has renewed the interest in NK cell based anti-cancer therapies, which has lead to a steady increase of NK cell based clinical and pre-clinical trials. Here, the role of NK cells in cancer immunesurveillance is summarized and several novel approaches to enhance NK cell cytotoxicity against cancer are discussed.

  15. GABAergic cells are the major postsynaptic targets of mossy fibers in the rat hippocampus.

    Science.gov (United States)

    Acsády, L; Kamondi, A; Sík, A; Freund, T; Buzsáki, G

    1998-05-01

    Dentate granule cells communicate with their postsynaptic targets by three distinct terminal types. These include the large mossy terminals, filopodial extensions of the mossy terminals, and smaller en passant synaptic varicosities. We examined the postsynaptic targets of mossy fibers by combining in vivo intracellular labeling of granule cells, immunocytochemistry, and electron microscopy. Single granule cells formed large, complex "mossy" synapses on 11-15 CA3 pyramidal cells and 7-12 hilar mossy cells. In contrast, GABAergic interneurons, identified with immunostaining for substance P-receptor, parvalbumin, and mGluR1a-receptor, were selectively innervated by very thin (filopodial) extensions of the mossy terminals and by small en passant boutons in both the hilar and CA3 regions. These terminals formed single, often perforated, asymmetric synapses on the cell bodies, dendrites, and spines of GABAergic interneurons. The number of filopodial extensions and small terminals was 10 times larger than the number of mossy terminals. These findings show that in contrast to cortical pyramidal neurons, (1) granule cells developed distinct types of terminals to affect interneurons and pyramidal cells and (2) they innervated more inhibitory than excitatory cells. These findings may explain the physiological observations that increased activity of granule cells suppresses the overall excitability of the CA3 recurrent system and may form the structural basis of the target-dependent regulation of glutamate release in the mossy fiber system.

  16. Expression and subcellular targeting of canine parvovirus capsid proteins in baculovirus-transduced NLFK cells.

    Science.gov (United States)

    Gilbert, Leona; Välilehto, Outi; Kirjavainen, Sanna; Tikka, Päivi J; Mellett, Mark; Käpylä, Pirjo; Oker-Blom, Christian; Vuento, Matti

    2005-01-17

    A mammalian baculovirus delivery system was developed to study targeting in Norden Laboratories feline kidney (NLFK) cells of the capsid proteins of canine parvovirus (CPV), VP1 and VP2, or corresponding counterparts fused to EGFP. VP1 and VP2, when expressed alone, both had equal nuclear and cytoplasmic distribution. However, assembled form of VP2 had a predominantly cytoplasmic localization. When VP1 and VP2 were simultaneously present in cells, their nuclear localization increased. Thus, confocal immunofluorescence analysis of cells transduced with the different baculovirus constructs or combinations thereof in the absence or presence of infecting CPV revealed that the VP1 protein is a prerequisite for efficient targeting of VP2 to the nucleus. The baculovirus vectors were functional and the genes of interest efficiently introduced to this CPV susceptible mammalian cell line. Thus, we show evidence that the system could be utilized to study targeting of the CPV capsid proteins.

  17. Radioiodinated Naphthylalanine Derivatives Targeting Pancreatic Beta Cells in Normal and Nonobese Diabetic Mice

    Science.gov (United States)

    Amartey, John K.; Shi, Yufei; Al-Jammaz, Ibrahim; Esguerra, Celestina; Al-Otaibi, Basem; Al-Mohanna, Futwan

    2008-01-01

    An imaging method capable of using a signal from pancreatic beta cells to determine their mass would be of immense value in monitoring the progression of diabetes as well as response to treatment. Somatostatin receptors (SSTRs) are expressed on beta cells and are a potential target for imaging. The main objective of this study was to investigate whether pancreatic beta cells are a target for radiolabeled naphthylalanine derivatives. The molecules were subjected to in vitro and ex vivo evaluations. Pancreatic uptake of radioactivity was lower in nonobese diabetic (NOD) mice than normal mice at all time points investigated (P < .05) and correlated with the number of islets in tissue sections of both control and NOD mice. Immunohistochemical and confocal fluorescent microscopic studies showed colocalization of insulin and the conjugate radioligand in the pancreas. The results demonstrated that pancreatic uptake is receptor-mediated, and that beta cells are the primary target. PMID:18483609

  18. Magnetic Nanoparticles for Targeting and Imaging of Stem Cells in Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Michelle R. Santoso

    2016-01-01

    Full Text Available Stem cell therapy has broad applications in regenerative medicine and increasingly within cardiovascular disease. Stem cells have emerged as a leading therapeutic option for many diseases and have broad applications in regenerative medicine. Injuries to the heart are often permanent due to the limited proliferation and self-healing capability of cardiomyocytes; as such, stem cell therapy has become increasingly important in the treatment of cardiovascular diseases. Despite extensive efforts to optimize cardiac stem cell therapy, challenges remain in the delivery and monitoring of cells injected into the myocardium. Other fields have successively used nanoscience and nanotechnology for a multitude of biomedical applications, including drug delivery, targeted imaging, hyperthermia, and tissue repair. In particular, superparamagnetic iron oxide nanoparticles (SPIONs have been widely employed for molecular and cellular imaging. In this mini-review, we focus on the application of superparamagnetic iron oxide nanoparticles in targeting and monitoring of stem cells for the treatment of myocardial infarctions.

  19. ErbB-targeted CAR T-cell immunotherapy of cancer.

    Science.gov (United States)

    Whilding, Lynsey M; Maher, John

    2015-01-01

    Chimeric antigen receptor (CAR) based immunotherapy has been under development for the last 25 years and is now a promising new treatment modality in the field of cancer immunotherapy. The approach involves genetically engineering T cells to target malignant cells through expression of a bespoke fusion receptor that couples an HLA-independent antigen recognition domain to one or more intracellular T-cell activating modules. Multiple clinical trials are now underway in several centers to investigate CAR T-cell immunotherapy of diverse hematologic and solid tumor types. The most successful results have been achieved in the treatment of patients with B-cell malignancies, in whom several complete and durable responses have been achieved. This review focuses on the preclinical and clinical development of CAR T-cell immunotherapy of solid cancers, targeted against members of the ErbB family.

  20. Targeting KIT on innate immune cells to enhance the antitumor activity of checkpoint inhibitors.

    Science.gov (United States)

    Stahl, Maximilian; Gedrich, Richard; Peck, Ronald; LaVallee, Theresa; Eder, Joseph Paul

    2016-06-01

    Innate immune cells such as mast cells and myeloid-derived suppressor cells are key components of the tumor microenvironment. Recent evidence indicates that levels of myeloid-derived suppressor cells in melanoma patients are associated with poor survival to checkpoint inhibitors. This suggests that targeting both the innate and adaptive suppressive components of the immune system will maximize clinical benefit and elicit more durable responses in cancer patients. Preclinical data suggest that targeting signaling by the receptor tyrosine kinase KIT, particularly on mast cells, may modulate innate immune cell numbers and activity in tumors. Here, we review data highlighting the importance of the KIT signaling in regulating antitumor immune responses and the potential benefit of combining selective KIT inhibitors with immune checkpoint inhibitors.

  1. Targeted antigen delivery to dendritic cells elicits robust antiviral T cell-mediated immunity in the liver

    Science.gov (United States)

    Volckmar, Julia; Gereke, Marcus; Ebensen, Thomas; Riese, Peggy; Philipsen, Lars; Lienenklaus, Stefan; Wohlleber, Dirk; Klopfleisch, Robert; Stegemann-Koniszewski, Sabine; Müller, Andreas J.; Gruber, Achim D.; Knolle, Percy; Guzman, Carlos A.; Bruder, Dunja

    2017-01-01

    Hepatotropic viruses such as hepatitis C virus cause life-threatening chronic liver infections in millions of people worldwide. Targeted in vivo antigen-delivery to cross-presenting dendritic cells (DCs) has proven to be extraordinarily efficient in stimulating antigen-specific T cell responses. To determine whether this approach would as well be suitable to induce local antiviral effector T cells in the liver we compared different vaccine formulations based on either the targeting of DEC-205 or TLR2/6 on cross-presenting DCs or formulations not involving in vivo DC targeting. As read-outs we used in vivo hepatotropic adenovirus challenge, histology and automated multidimensional fluorescence microscopy (MELC). We show that targeted in vivo antigen delivery to cross-presenting DCs is highly effective in inducing antiviral CTLs capable of eliminating virus-infected hepatocytes, while control vaccine formulation not involving DC targeting failed to induce immunity against hepatotropic virus. Moreover, we observed distinct patterns of CD8+ T cell interaction with virus-infected and apoptotic hepatocytes in the two DC-targeting groups suggesting that the different vaccine formulations may stimulate distinct types of effector functions. Our findings represent an important step toward the future development of vaccines against hepatotropic viruses and the treatment of patients with hepatic virus infection after liver transplantation to avoid reinfection. PMID:28266658

  2. In vivo targeting of antigens to maturing dendritic cells via the DEC-205 receptor improves T cell vaccination.

    Science.gov (United States)

    Bonifaz, Laura C; Bonnyay, David P; Charalambous, Anna; Darguste, Dara I; Fujii, Shin-Ichiro; Soares, Helena; Brimnes, Marie K; Moltedo, Bruno; Moran, Thomas M; Steinman, Ralph M

    2004-03-15

    The prevention and treatment of prevalent infectious diseases and tumors should benefit from improvements in the induction of antigen-specific T cell immunity. To assess the potential of antigen targeting to dendritic cells to improve immunity, we incorporated ovalbumin protein into a monoclonal antibody to the DEC-205 receptor, an endocytic receptor that is abundant on these cells in lymphoid tissues. Simultaneously, we injected agonistic alpha-CD40 antibody to mature the dendritic cells. We found that a single low dose of antibody-conjugated ovalbumin initiated immunity from the naive CD4+ and CD8+ T cell repertoire. Unexpectedly, the alphaDEC-205 antigen conjugates, given s.c., targeted to dendritic cells systemically and for long periods, and ovalbumin peptide was presented on MHC class I for 2 weeks. This was associated with stronger CD8+ T cell-mediated immunity relative to other forms of antigen delivery, even when the latter was given at a thousand times higher doses. In parallel, the mice showed enhanced resistance to an established rapidly growing tumor and to viral infection at a mucosal site. By better harnessing the immunizing functions of maturing dendritic cells, antibody-mediated antigen targeting via the DEC-205 receptor increases the efficiency of vaccination for T cell immunity, including systemic and mucosal resistance in disease models.

  3. Display of GPI-anchored anti-EGFR nanobodies on extracellular vesicles promotes tumour cell targeting

    Directory of Open Access Journals (Sweden)

    Sander A. A. Kooijmans

    2016-03-01

    Full Text Available Background: Extracellular vesicles (EVs are attractive candidate drug delivery systems due to their ability to functionally transport biological cargo to recipient cells. However, the apparent lack of target cell specificity of exogenously administered EVs limits their therapeutic applicability. In this study, we propose a novel method to equip EVs with targeting properties, in order to improve their interaction with tumour cells. Methods: EV producing cells were transfected with vectors encoding for anti-epidermal growth factor receptor (EGFR nanobodies, which served as targeting ligands for tumour cells, fused to glycosylphosphatidylinositol (GPI anchor signal peptides derived from decay-accelerating factor (DAF. EVs were isolated using ultrafiltration/size-exclusion liquid chromatography and characterized using western blotting, Nanoparticle Tracking Analysis, and electron microscopy. EV–tumour cell interactions were analyzed under static conditions using flow cytometry and under flow conditions using a live-cell fluorescence microscopy-coupled perfusion system. Results: V analysis showed that GPI-linked nanobodies were successfully displayed on EV surfaces and were highly enriched in EVs compared with parent cells. Display of GPI-linked nanobodies on EVs did not alter general EV characteristics (i.e. morphology, size distribution and protein marker expression, but greatly improved EV binding to tumour cells dependent on EGFR density under static conditions. Moreover, nanobody-displaying EVs showed a significantly improved cell association to EGFR-expressing tumour cells under flow conditions. Conclusions: We show that nanobodies can be anchored on the surface of EVs via GPI, which alters their cell targeting behaviour. Furthermore, this study highlights GPI-anchoring as a new tool in the EV toolbox, which may be applied for EV display of a variety of proteins, such as antibodies, reporter proteins and signaling molecules.

  4. Display of GPI-anchored anti-EGFR nanobodies on extracellular vesicles promotes tumour cell targeting

    Science.gov (United States)

    Kooijmans, Sander A. A.; Aleza, Clara Gómez; Roffler, Steve R.; van Solinge, Wouter W.; Vader, Pieter; Schiffelers, Raymond M.

    2016-01-01

    Background Extracellular vesicles (EVs) are attractive candidate drug delivery systems due to their ability to functionally transport biological cargo to recipient cells. However, the apparent lack of target cell specificity of exogenously administered EVs limits their therapeutic applicability. In this study, we propose a novel method to equip EVs with targeting properties, in order to improve their interaction with tumour cells. Methods EV producing cells were transfected with vectors encoding for anti-epidermal growth factor receptor (EGFR) nanobodies, which served as targeting ligands for tumour cells, fused to glycosylphosphatidylinositol (GPI) anchor signal peptides derived from decay-accelerating factor (DAF). EVs were isolated using ultrafiltration/size-exclusion liquid chromatography and characterized using western blotting, Nanoparticle Tracking Analysis, and electron microscopy. EV–tumour cell interactions were analyzed under static conditions using flow cytometry and under flow conditions using a live-cell fluorescence microscopy-coupled perfusion system. Results EV analysis showed that GPI-linked nanobodies were successfully displayed on EV surfaces and were highly enriched in EVs compared with parent cells. Display of GPI-linked nanobodies on EVs did not alter general EV characteristics (i.e. morphology, size distribution and protein marker expression), but greatly improved EV binding to tumour cells dependent on EGFR density under static conditions. Moreover, nanobody-displaying EVs showed a significantly improved cell association to EGFR-expressing tumour cells under flow conditions. Conclusions We show that nanobodies can be anchored on the surface of EVs via GPI, which alters their cell targeting behaviour. Furthermore, this study highlights GPI-anchoring as a new tool in the EV toolbox, which may be applied for EV display of a variety of proteins, such as antibodies, reporter proteins and signaling molecules. PMID:26979463

  5. Novel Roles for P53 in the Genesis and Targeting of Tetraploid Cancer Cells

    OpenAIRE

    Batzaya Davaadelger; Hong Shen; Maki, Carl G.

    2014-01-01

    Tetraploid (4N) cells are considered important in cancer because they can display increased tumorigenicity, resistance to conventional therapies, and are believed to be precursors to whole chromosome aneuploidy. It is therefore important to determine how tetraploid cancer cells arise, and how to target them. P53 is a tumor suppressor protein and key regulator of tetraploidy. As part of the "tetraploidy checkpoint", p53 inhibits tetraploid cell proliferation by promoting a G1-arrest in incipie...

  6. Temporally controlled targeting of 4-hydroxynonenal to specific proteins in living cells.

    Science.gov (United States)

    Fang, Xinqiang; Fu, Yuan; Long, Marcus J C; Haegele, Joseph A; Ge, Eva J; Parvez, Saba; Aye, Yimon

    2013-10-02

    In-depth chemical understanding of complex biological processes hinges upon the ability to systematically perturb individual systems. However, current approaches to study impacts of biologically relevant reactive small molecules involve bathing of the entire cell or isolated organelle with excess amounts, leading to off-target effects. The resultant lack of biochemical specificity has plagued our understanding of how biological electrophiles mediate signal transduction or regulate responses that confer defense mechanisms to cellular electrophilic stress. Here we introduce a target-specific electrophile delivery platform that will ultimately pave the way to interrogate effects of reactive electrophiles on specific target proteins in cells. The new methodology is demonstrated by photoinducible targeted delivery of 4-hydroxynonenal (HNE) to the proteins Keap1 and PTEN. Covalent conjugation of the HNE-precursor to HaloTag fused to the target proteins enables directed HNE delivery upon photoactivation. The strategy provides proof of concept of selective delivery of reactive electrophiles to individual electrophile-responsive proteins in mammalian cells. It opens a new avenue enabling more precise determination of the pathophysiological consequences of HNE-induced chemical modifications on specific target proteins in cells.

  7. Designing nanoconjugates to effectively target pancreatic cancer cells in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Jameel Ahmad Khan

    Full Text Available BACKGROUND: Pancreatic cancer is the fourth leading cause of cancer related deaths in America. Monoclonal antibodies are a viable treatment option for inhibiting cancer growth. Tumor specific drug delivery could be achieved utilizing these monoclonal antibodies as targeting agents. This type of designer therapeutic is evolving and with the use of gold nanoparticles it is a promising approach to selectively deliver chemotherapeutics to malignant cells. Gold nanoparticles (GNPs are showing extreme promise in current medicinal research. GNPs have been shown to non-invasively kill tumor cells by hyperthermia using radiofrequency. They have also been implemented as early detection agents due to their unique X-ray contrast properties; success was revealed with clear delineation of blood capillaries in a preclinical model by CT (computer tomography. The fundamental parameters for intelligent design of nanoconjugates are on the forefront. The goal of this study is to define the necessary design parameters to successfully target pancreatic cancer cells. METHODOLOGY/PRINCIPAL FINDINGS: The nanoconjugates described in this study were characterized with various physico-chemical techniques. We demonstrate that the number of cetuximab molecules (targeting agent on a GNP, the hydrodynamic size of the nanoconjugates, available reactive surface area and the ability of the nanoconjugates to sequester EGFR (epidermal growth factor receptor, all play critical roles in effectively targeting tumor cells in vitro and in vivo in an orthotopic model of pancreatic cancer. CONCLUSION: Our results suggest the specific targeting of tumor cells depends on a number of crucial components 1 targeting agent to nanoparticle ratio 2 availability of reactive surface area on the nanoparticle 3 ability of the nanoconjugate to bind the target and 4 hydrodynamic diameter of the nanoconjugate. We believe this study will help define the design parameters for formulating better strategies

  8. Adoptive transfer of osteoclast-expanded natural killer cells for immunotherapy targeting cancer stem-like cells in humanized mice.

    Science.gov (United States)

    Kozlowska, Anna K; Kaur, Kawaljit; Topchyan, Paytsar; Jewett, Anahid

    2016-07-01

    Based on data obtained from oral, pancreatic and lung cancers, glioblastoma, and melanoma, we have established that natural killer (NK) cells target cancer stem-like cells (CSCs). CSCs displaying low MHC class I, CD54, and PD-L1 are killed by cytotoxic NK cells and are differentiated by split anergized NK cells through both membrane bound and secreted forms of TNF-α and IFN-γ. NK cells select and differentiate both healthy and transformed stem-like cells, resulting in target cell maturation and shaping of their microenvironment. In our recent studies, we have observed that oral, pancreatic, and melanoma CSCs were capable of forming large tumors in humanized bone marrow, liver, thymus (hu-BLT) mice with fully reconstituted human immune system. In addition, major human immune subsets including NK cells, T cells, B cells, and monocytes were present in the spleen, bone marrow, peripheral blood, and tumor microenvironment. Similar to our previously published in vitro data, CSCs differentiated with split anergized NK cells prior to implantation in mice formed smaller tumors. Intravenous injection of functionally potent osteoclast-expanded NK cells inhibited tumor growth through differentiation of CSCs in humanized mice. In this review, we present current approaches, advances, and existing limitations in studying interactions of the immune system with the tumor, in particular NK cells with CSCs, using in vivo preclinical hu-BLT mouse model. In addition, we discuss the use of osteoclast-expanded NK cells in targeting cancer stem-like tumors in humanized mice-a strategy that provides a much-needed platform to develop effective cancer immunotherapies.

  9. Targeted images of KB cells using folate-conjugated gold nanoparticles

    Science.gov (United States)

    Rathinaraj, Pierson; Lee, Kyubae; Park, Soo-Young; Kang, Inn-Kyu

    2015-01-01

    Mercaptosuccinic acid-coated gold (GM) nanoparticles were prepared and characterized by transmission electron microscopy and dynamic light scattering. Folic acid (F) was then conjugated to the GM to preferentially target oral squamous cancer (KB) cells with folate receptors expressed on their membranes and facilitate the transit of the nanoparticles across the cell membrane. Finally, a fluorescence dye (Atto) was conjugated to the nanoparticles to visualize their internalization into KB cells. After culture of the cells in a medium containing GM and folate-conjugated GM (GF), the interaction of surface-modified gold nanoparticles with KB cells was studied.

  10. Nanobiotechnology meets plant cell biology: Carbon nanotubes as organelle targeting nanocarriers

    KAUST Repository

    Bayoumi, Maged Fouad

    2013-01-01

    For years, nanotechnology has shown great promise in the fields of biomedical and biotechnological sciences and medical research. In this review, we demonstrate its versatility and applicability in plant cell biology studies. Specifically, we discuss the ability of functionalized carbon nanotubes to penetrate the plant cell wall, target specific organelles, probe protein-carrier activity and induce organelle recycling in plant cells. We also, shed light on prospective applications of carbon nanomaterials in cell biology and plant cell transformation. © 2013 The Royal Society of Chemistry.

  11. Notch signaling: targeting cancer stem cells and epithelial-to-mesenchymal transition.

    Science.gov (United States)

    Espinoza, Ingrid; Pochampally, Radhika; Xing, Fei; Watabe, Kounosuke; Miele, Lucio

    2013-09-06

    Notch signaling is an evolutionarily conserved pathway involved in cell fate control during development, stem cell self-renewal, and postnatal tissue differentiation. Roles for Notch in carcinogenesis, the biology of cancer stem cells, tumor angiogenesis, and epithelial-to-mesenchymal transition (EMT) have been reported. This review describes the role of Notch in the "stemness" program in cancer cells and in metastases, together with a brief update on the Notch inhibitors currently under investigation in oncology. These agents may be useful in targeting cancer stem cells and to reverse the EMT process.

  12. Folic acid-CdTe quantum dot conjugates and their applications for cancer cell targeting

    Energy Technology Data Exchange (ETDEWEB)

    Suriamoorthy, Preethi; Zhang, Xing; Hao, Guiyang; Joly, Alan G.; Singh, S.; Hossu, Marius; Sun, Xiankai; Chen, Wei

    2010-12-01

    In this study, we report the preparation,luminescence, and targeting properties of folic acid- CdTe quantum dot conjugates. Water-soluble CdTe quantum dots were synthesized and conjugated with folic acid using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide-N-hydroxysuccinimide chemistry. The in-fluence of folic acid on the luminescence properties of CdTe quantum dots was investigated, and no energy transfer between them was observed. To investigate the efficiency of folic acid-CdTe nanoconjugates for tumor targeting, pure CdTe quantum dots and folic acid-coated CdTe quantum dots were incubated with human naso- pharyngeal epidermal carcinoma cell line with positive expressing folic acid receptors (KB cells) and lung cancer cells without expression of folic acid receptors (A549 cells). For the cancer cells with positive folate receptors (KB cells), the uptake for CdTe quantum dots is very low, but for folic acid-CdTe nanoconjugates, the uptake is very high. For the lung cancer cells without folate receptors (A549 cells), the uptake for folic acid- CdTe nanoconjugates is also very low. The results indicate that folic acid is an effective targeting molecule for tumor cells with overexpressed folate receptors.

  13. CollagenVI-Cre mice: A new tool to target stromal cells in secondary lymphoid organs.

    Science.gov (United States)

    Prados, Alejandro; Kollias, George; Koliaraki, Vasiliki

    2016-09-08

    Stromal cells in secondary lymphoid organs (SLOs) are non-hematopoietic cells involved in the regulation of adaptive immune responses. Three major stromal populations have been identified in adult SLOs: fibroblastic reticular cells (FRCs), follicular dendritic cells (FDCs) and marginal reticular cells (MRCs). The properties of these individual populations are not clearly defined, mainly due to the lack of appropriate genetic tools, especially for MRCs. Here, we analyzed stromal cell targeting in SLOs from a transgenic mouse strain that expresses Cre recombinase under the CollagenVI promoter, using lineage tracing approaches. We show that these mice target specifically MRCs and FDCs, but not FRCs in Peyer's patches and isolated lymphoid follicles in the intestine. In contrast, stromal cells in lymph nodes and the spleen do not express the transgene, which renders ColVI-cre mice ideal for the specific targeting of stromal cells in the gut-associated lymphoid tissue (GALT). This funding further supports the hypothesis of organ-specific stromal precursors in SLOs. Interestingly, in all tissues analyzed, there was also high specificity for perivascular cells, which have been proposed to act as FDC precursors. Taken together, ColVI-Cre mice are a useful new tool for the dissection of MRC- and FDC-specific functions and plasticity in the GALT.

  14. Gene Transfer from Targeted Liposomes to Specific Lymphoid Cells by Electroporation

    Science.gov (United States)

    Machy, Patrick; Lewis, Florence; McMillan, Lynette; Jonak, Zdenka L.

    1988-11-01

    Large unilamellar liposomes, coated with protein A and encapsulating the gene that confers resistance to mycophenolic acid, were used as a model system to demonstrate gene transfer into specific lymphoid cells. Protein A, which selectively recognizes mouse IgG2a antibodies, was coupled to liposomes to target them specifically to defined cell types coated with IgG2a antibody. Protein A-coated liposomes bound human B lymphoblastoid cells preincubated with a mouse IgG2a anti-HLA monoclonal antibody but failed to adhere to cells challenged with an irrelevant (anti-H-2) antibody of the same isotype or to cells incubated in the absence of antibody. Transfection of target cells bound to protein A-coated liposomes was achieved by electroporation. This step was essential since only electroporated cells survived in a selective medium containing mycophenolic acid. Transfection efficiency with electroporation and targeted liposomes was as efficient as conventional procedures that used unencapsulated plasmids free in solution but, in the latter case, cell selectivity is not possible. This technique provides a methodology for introducing defined biological macromolecules into specific cell types.

  15. 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.

  16. Targeted alternative splicing of TAF4: a new strategy for cell reprogramming

    Science.gov (United States)

    Kazantseva, Jekaterina; Sadam, Helle; Neuman, Toomas; Palm, Kaia

    2016-01-01

    Reprogramming of somatic cells has become a versatile tool for biomedical research and for regenerative medicine. In the current study, we show that manipulating alternative splicing (AS) is a highly potent strategy to produce cells for therapeutic applications. We demonstrate that silencing of hTAF4-TAFH activity of TAF4 converts human facial dermal fibroblasts to melanocyte-like (iMel) cells. iMel cells produce melanin and express microphthalmia-associated transcription factor (MITF) and its target genes at levels comparable to normal melanocytes. Reprogramming of melanoma cells by manipulation with hTAF4-TAFH activity upon TAFH RNAi enforces cell differentiation towards chondrogenic pathway, whereas ectoptic expression of TAF4 results in enhanced multipotency and neural crest-like features in melanoma cells. In both cell states, iMels and cancer cells, hTAF4-TAFH activity controls migration by supporting E- to N-cadherin switches. From our data, we conclude that targeted splicing of hTAF4-TAFH coordinates AS of other TFIID subunits, underscoring the role of TAF4 in synchronised changes of Pol II complex composition essential for efficient cellular reprogramming. Taken together, targeted AS of TAF4 provides a unique strategy for generation of iMels and recapitulating stages of melanoma progression. PMID:27499390

  17. Determining duration of HER2-targeted therapy using stem cell extinction models.

    Directory of Open Access Journals (Sweden)

    Lindsay Riley

    Full Text Available INTRODUCTION: Trastuzumab dramatically improves survival in breast cancer patients whose tumor overexpresses HER2. A subpopulation of cells in human breast tumors has been identified with characteristics of cancer stem cells. These breast cancer stem-like cells (BCSCs rely on HER2 signaling for self-renewal, suggesting that HER2-targeted therapy targets BCSCs even when the bulk of the tumor does not overexpress HER2. In order to guide clinical trials examining HER2-targeted therapy in the adjuvant setting, we propose a mathematical model to examine BCSC population dynamics and predict optimal duration of therapy. METHODS: Varying the susceptibility of BCSCs to HER2-targeted therapy, we quantify the average time to extinction of BCSCs. We expand our model using stochastic simulation to include the partially differentiated tumor cells (TCs that represent bulk tumor population and examine effects of plasticity on required duration of therapy. RESULTS: Lower susceptibility of BCSCs and increased rates of dedifferentiation entail longer extinction times, indicating a need for prolonged administration of HER2-targeted therapy. We predict that even when therapy does not appreciably reduce tumor size in the advanced cancer setting, it will eventually eradicate the tumor in the adjuvant setting as long as there is at least a modest effect on BCSCs. CONCLUSIONS: We anticipate that our results will inform clinical trials of targeted therapies in planning the duration of therapy needed to eradicate BCSCs. Our predictions also address safety, as longer duration of therapy entails a greater potential impact on normal stem cells that may also be susceptible to stem cell-targeted therapies.

  18. Single cell targeting using plasmon resonant gold-coated liposomes

    Science.gov (United States)

    Leung, Sarah J.; Romanowski, Marek

    2012-03-01

    We have developed an experimental system with the potential for the delivery and localized release of an encapsulated agent with high spatial and temporal resolution. We previously introduced liposome-supported plasmon resonant gold nanoshells; in this composite structure, the liposome allows for the encapsulation of substances, such as therapeutic agents, neurotransmitters, or growth factors, and the plasmon resonant structure facilitates the rapid release of encapsulated contents upon laser light illumination. More recently, we demonstrated that these gold-coated liposomes are capable of releasing their contents in a spectrally-controlled manner, where plasmon resonant nanoparticles only release content upon illumination with a wavelength of light matching their plasmon resonance band. We now show that this release mechanism can be used in a biological setting to deliver a peptide derivative of cholecystokinin to HEK293 cells overexpressing the CCK2 receptor. Using directed laser light, we may enable localized release from gold-coated liposomes to enable accurate perturbation of cellular functions in response to released compounds; this system may have possible applications in signaling pathways and drug discovery.

  19. Sickle cell disease: time for a targeted neonatal screening programme.

    LENUS (Irish Health Repository)

    Gibbons, C

    2015-02-01

    Ireland has seen a steady increase in paediatric sickle cell disease (SCD). In 2005, only 25% of children with SCD were referred to the haemoglobinopathy service in their first year. A non-funded screening programme was implemented. This review aimed to assess the impact screening has had. All children referred to the haemoglobinopathy service born in Ireland after 2005 were identified. Data was collected from the medical chart and laboratory system. Information was analysed using Microsoft Excel. 77 children with SCD were identified. The median age at antibiotic commencement in the screened group was 56 days compared with 447 days in the unscreened group, p = < 0.0003. 22 (28%) of infants were born in centre\\'s that do not screen and 17 (81%) were over 6 months old at referral, compared with 14 (21%) in the screened group. 6 (27%) of those in the unscreened group presented in acute crisis compared with 2 (3%) in the screened population. The point prevalence of SCD in Ireland is 0.2% in children under 15 yr of African and Asian descent. We identified delays in referral and treatment, which reflect the lack of government funded support and policy. We suggest all maternity units commence screening for newborns at risk of SCD. It is a cost effective intervention with a number needed to screen of just 4 to prevent a potentially fatal crisis.

  20. Targeting Th17 Cells with Small Molecules and Small Interference RNA.

    Science.gov (United States)

    Lin, Hui; Song, Pingfang; Zhao, Yi; Xue, Li-Jia; Liu, Yi; Chu, Cong-Qiu

    2015-01-01

    T helper 17 (Th17) cells play a central role in inflammatory and autoimmune diseases via the production of proinflammatory cytokines interleukin- (IL-) 17, IL-17F, and IL-22. Anti-IL-17 monoclonal antibodies show potent efficacy in psoriasis but poor effect in rheumatoid arthritis (RA) and Crohn's disease. Alternative agents targeting Th17 cells may be a better way to inhibit the development and function of Th17 cells than antibodies of blocking a single effector cytokine. Retinoic acid-related orphan receptor gamma t (RORγt) which acts as the master transcription factor of Th17 differentiation has been an attractive pharmacologic target for the treatment of Th17-mediated autoimmune disease. Recent progress in technology of chemical screen and engineering nucleic acid enable two new classes of therapeutics targeting RORγt. Chemical screen technology identified several small molecule specific inhibitors of RORγt from a small molecule library. Systematic evolution of ligands by exponential enrichment (SELEX) technology enabled target specific aptamers to be isolated from a random sequence oligonucleotide library. In this review, we highlight the development and therapeutic potential of small molecules inhibiting Th17 cells by targeting RORγt and aptamer mediated CD4(+) T cell specific delivery of small interference RNA against RORγt gene expression to inhibit pathogenic effector functions of Th17 lineage.

  1. Unusual target selectivity of perisomatic inhibitory cells in the hilar region of the rat hippocampus.

    Science.gov (United States)

    Acsády, L; Katona, I; Martínez-Guijarro, F J; Buzsáki, G; Freund, T F

    2000-09-15

    Perisomatic inhibitory innervation of all neuron types profoundly affects their firing characteristics and vulnerability. In this study we examined the postsynaptic targets of perisomatic inhibitory cells in the hilar region of the dentate gyrus where the proportion of potential target cells (excitatory mossy cells and inhibitory interneurons) is approximately equal. Both cholecystokinin (CCK)- and parvalbumin-immunoreactive basket cells formed multiple contacts on the somata and proximal dendrites of mossy cells. Unexpectedly, however, perisomatic inhibitory terminals arriving from these cell types largely ignored hilar GABAergic cell populations. Eighty-ninety percent of various GABAergic neurons including other CCK-containing basket cells received no input from CCK-positive terminals. Parvalbumin-containing cells sometimes innervated each other but avoided 75% of other GABAergic cells. Overall, a single mossy cell received 40 times more CCK-immunoreactive terminals and 15 times more parvalbumin-positive terminals onto its soma than the cell body of an average hilar GABAergic cell. In contrast to the pronounced target selectivity in the hilar region, CCK- and parvalbumin-positive neurons innervated each other via collaterals in stratum granulosum and moleculare. Our observations indicate that the inhibitory control in the hilar region is qualitatively different from other cortical areas at both the network level and the level of single neurons. The paucity of perisomatic innervation of hilar interneurons should have profound consequences on their action potential generation and on their ensemble behavior. These findings may help explain the unique physiological patterns observed in the hilus and the selective vulnerability of the hilar cell population in various pathophysiological conditions.

  2. Aptamer-targeted inhibition of mTOR in T cells enhances antitumor immunity.

    Science.gov (United States)

    Berezhnoy, Alexey; Castro, Iris; Levay, Agata; Malek, Thomas R; Gilboa, Eli

    2014-01-01

    Recent studies have underscored the importance of memory T cells in mediating protective immunity against pathogens and cancer. Pharmacological inhibition of regulators that mediate T cell differentiation promotes the differentiation of activated CD8(+) T cells into memory cells. Nonetheless, pharmacological agents have broad targets and can induce undesirable immunosuppressive effects. Here, we tested the hypothesis that aptamer-targeted siRNA inhibition of mTOR complex 1 (mTORC1) function in CD8(+) T cells can enhance their differentiation into memory T cells and potentiate antitumor immunity more effectively than the pharmacologic inhibitor rapamycin. To specifically target activated cells, we conjugated an siRNA targeting the mTORC1 component raptor to an aptamer that binds 4-1BB, a costimulatory molecule that is expressed on CD8(+) T cells following TCR stimulation. We found that systemic administration of the 4-1BB aptamer-raptor siRNA to mice downregulated mTORC1 activity in the majority of CD8(+) T cells, leading to the generation of a potent memory response that exhibited cytotoxic effector functions and enhanced vaccine-induced protective immunity in tumor-bearing mice. In contrast, while treatment with the general mTORC1 inhibitor rapamycin also enhanced antigen-activated CD8(+) T cell persistence, the cytotoxic effector functions of the reactivated memory cells were reduced and the alloreactivity of DCs was diminished. Consistent with the immunological findings, mice treated with rapamycin, but not with 4-1BB aptamer-raptor siRNA, failed to reject a subsequent tumor challenge.

  3. Visual cells remember earlier applied target: plasticity of orientation selectivity.

    Directory of Open Access Journals (Sweden)

    Narcis Ghisovan

    Full Text Available BACKGROUND: A canonical proposition states that, in mature brain, neurons responsive to sensory stimuli are tuned to specific properties installed shortly after birth. It is amply demonstrated that that neurons in adult visual cortex of cats are orientation-selective that is they respond with the highest firing rates to preferred oriented stimuli. METHODOLOGY/PRINCIPAL FINDINGS: In anesthetized cats, prepared in a conventional fashion for single cell recordings, the present investigation shows that presenting a stimulus uninterruptedly at a non-preferred orientation for twelve minutes induces changes in orientation preference. Across all conditions orientation tuning curves were investigated using a trial by trial method. Contrary to what has been previously reported with shorter adaptation duration, twelve minutes of adaptation induces mostly attractive shifts, i.e. toward the adapter. After a recovery period allowing neurons to restore their original orientation tuning curves, we carried out a second adaptation which produced three major results: (1 more frequent attractive shifts, (2 an increase of their magnitude, and (3 an additional enhancement of responses at the new or acquired preferred orientation. Additionally, we also show that the direction of shifts depends on the duration of the adaptation: shorter adaptation in most cases produces repulsive shifts, whereas adaptation exceeding nine minutes results in attractive shifts, in the same unit. Consequently, shifts in preferred orientation depend on the duration of adaptation. CONCLUSION/SIGNIFICANCE: The supplementary response improvements indicate that neurons in area 17 keep a memory trace of the previous stimulus properties, thereby upgrading cellular performance. It also highlights the dynamic nature of basic neuronal properties in adult cortex since repeated adaptations modified both the orientation tuning selectivity and the response strength to the preferred orientation. These

  4. Target engagement and drug residence time can be observed in living cells with BRET.

    Science.gov (United States)

    Robers, Matthew B; Dart, Melanie L; Woodroofe, Carolyn C; Zimprich, Chad A; Kirkland, Thomas A; Machleidt, Thomas; Kupcho, Kevin R; Levin, Sergiy; Hartnett, James R; Zimmerman, Kristopher; Niles, Andrew L; Ohana, Rachel Friedman; Daniels, Danette L; Slater, Michael; Wood, Monika G; Cong, Mei; Cheng, Yi-Qiang; Wood, Keith V

    2015-12-03

    The therapeutic action of drugs is predicated on their physical engagement with cellular targets. Here we describe a broadly applicable method using bioluminescence resonance energy transfer (BRET) to reveal the binding characteristics of a drug with selected targets within intact cells. Cell-permeable fluorescent tracers are used in a competitive binding format to quantify drug engagement with the target proteins fused to Nanoluc luciferase. The approach enabled us to profile isozyme-specific engagement and binding kinetics for a panel of histone deacetylase (HDAC) inhibitors. Our analysis was directed particularly to the clinically approved prodrug FK228 (Istodax/Romidepsin) because of its unique and largely unexplained mechanism of sustained intracellular action. Analysis of the binding kinetics by BRET revealed remarkably long intracellular residence times for FK228 at HDAC1, explaining the protracted intracellular behaviour of this prodrug. Our results demonstrate a novel application of BRET for assessing target engagement within the complex milieu of the intracellular environment.

  5. Hyaluronic acid modified mesoporous carbon nanoparticles for targeted drug delivery to CD44-overexpressing cancer cells

    Science.gov (United States)

    Wan, Long; Jiao, Jian; Cui, Yu; Guo, Jingwen; Han, Ning; Di, Donghua; Chang, Di; Wang, Pu; Jiang, Tongying; Wang, Siling

    2016-04-01

    In this paper, hyaluronic acid (HA) functionalized uniform mesoporous carbon spheres (UMCS) were synthesized for targeted enzyme responsive drug delivery using a facile electrostatic attraction strategy. This HA modification ensured stable drug encapsulation in mesoporous carbon nanoparticles in an extracellular environment while increasing colloidal stability, biocompatibility, cell-targeting ability, and controlled cargo release. The cellular uptake experiments of fluorescently labeled mesoporous carbon nanoparticles, with or without HA functionalization, demonstrated that HA-UMCS are able to specifically target cancer cells overexpressing CD44 receptors. Moreover, the cargo loaded doxorubicin (DOX) and verapamil (VER) exhibited a dual pH and hyaluronidase-1 responsive release in the tumor microenvironment. In addition, VER/DOX/HA-UMCS exhibited a superior therapeutic effect on an in vivo HCT-116 tumor in BALB/c nude mice. In summary, it is expected that HA-UMCS will offer a new method for targeted co-delivery of drugs to tumors overexpressing CD44 receptors.

  6. CRISPR-Cas9 nuclear dynamics and target recognition in living cells.

    Science.gov (United States)

    Ma, Hanhui; Tu, Li-Chun; Naseri, Ardalan; Huisman, Maximiliaan; Zhang, Shaojie; Grunwald, David; Pederson, Thoru

    2016-08-29

    The bacterial CRISPR-Cas9 system has been repurposed for genome engineering, transcription modulation, and chromosome imaging in eukaryotic cells. However, the nuclear dynamics of clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) guide RNAs and target interrogation are not well defined in living cells. Here, we deployed a dual-color CRISPR system to directly measure the stability of both Cas9 and guide RNA. We found that Cas9 is essential for guide RNA stability and that the nuclear Cas9-guide RNA complex levels limit the targeting efficiency. Fluorescence recovery after photobleaching measurements revealed that single mismatches in the guide RNA seed sequence reduce the target residence time from >3 h to as low as CRISPR discriminates between genuine versus mismatched targets for genome editing via radical alterations in residence time.

  7. Targeting the cell cycle in esophageal adenocarcinoma: an adjunct to anticancer treatment.

    Science.gov (United States)

    Dibb, Martyn; Ang, Yeng S

    2011-04-28

    Esophageal adenocarcinoma is a major cause of cancer death in men in the developed world. Continuing poor outcomes with conventional therapies that predominantly target apoptosis pathways have lead to increasing interest in treatments that target the cell cycle. A large international effort has led to the development of a large number of inhibitors, which target cell cycle kinases, including cyclin-dependent kinases, Aurora kinases and polo-like kinase. Initial phase I/II trials in solid tumors have often demonstrated only modest clinical benefits of monotherapy. This may relate in part to a failure to identify the patient populations that will gain the most clinical benefit. Newer compounds lacking the side effect profile of first-generation compounds may show utility as adjunctive treatments targeted to an individual's predicted response to treatment.

  8. Targeting the cell cycle in esophageal adenocarcinoma: An adjunct to anticancer treatment

    Institute of Scientific and Technical Information of China (English)

    Martyn Dibb; Yeng S Ang

    2011-01-01

    Esophageal adenocarcinoma is a major cause of cancer death in men in the developed world. Continuing poor outcomes with conventional therapies that predomi-nantly target apoptosis pathways have lead to increas-ing interest in treatments that target the cell cycle. A large international effort has led to the development of a large number of inhibitors, which target cell cycle kinases, including cyclin-dependent kinases, Aurora ki-nases and polo-like kinase. Initial phaseⅠ/Ⅱtrials in solid tumors have often demonstrated only modest clinical benefits of monotherapy. This may relate in part to a failure to identify the patient populations that will gain the most clinical benefit. Newer compounds lacking the side effect profile of first-generation compounds may show utility as adjunctive treatments targeted to an in-dividual's predicted response to treatment.

  9. Cell-specific biomarkers and targeted biopharmaceuticals for breast cancer treatment.

    Science.gov (United States)

    Liu, Mei; Li, Zhiyang; Yang, Jingjing; Jiang, Yanyun; Chen, Zhongsi; Ali, Zeeshan; He, Nongyue; Wang, Zhifei

    2016-08-01

    Breast cancer is the second leading cause of cancer death among women, and its related treatment has been attracting significant attention over the past decades. Among the various treatments, targeted therapy has shown great promise as a precision treatment, by binding to cancer cell-specific biomarkers. So far, great achievements have been made in targeted therapy of breast cancer. In this review, we first discuss cell-specific biomarkers, which are not only useful for classification of breast cancer subtyping but also can be utilized as goals for targeted therapy. Then, the innovative and generic-targeted biopharmaceuticals for breast cancer, including monoclonal antibodies, non-antibody proteins and small molecule drugs, are reviewed. Finally, we provide our outlook on future developments of biopharmaceuticals, and provide solutions to problems in this field.

  10. [Current strategies in the treatment of renal-cell cancer: targeted therapies].

    Science.gov (United States)

    Trigo, José Manuel; Bellmunt, Joaquim

    2008-03-22

    Renal-cell carcinoma represents 95% of all renal tumours. The Von Hippel-Lindau (VHL) tumor-suppressor gene is mutated or silenced in most clear cell renal carcinomas. pVHL loss results in the stabilization of the heterodimeric transcription factor hypoxia-inducible factor (HIF) and enhanced transactivation of HIF target genes. HIF itself has been difficult to inhibit with drug-like molecules although a number of agents that indirectly inhibit HIF, including mTOR (mammalian target of rapamycin) inhibitors, have been identified. Moreover, a number of drugs have been developed that target HIF-responsive gene products, such as vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), implicated in tumor angiogenesis. Many of these targeted therapies, especially sunitinib, have demonstrated significant activity in kidney cancer clinical trials and represent a substantive advance in the treatment of this disease.

  11. Targeting single neuronal networks for gene expression and cell labeling in vivo.

    Science.gov (United States)

    Marshel, James H; Mori, Takuma; Nielsen, Kristina J; Callaway, Edward M

    2010-08-26

    To understand fine-scale structure and function of single mammalian neuronal networks, we developed and validated a strategy to genetically target and trace monosynaptic inputs to a single neuron in vitro and in vivo. The strategy independently targets a neuron and its presynaptic network for specific gene expression and fine-scale labeling, using single-cell electroporation of DNA to target infection and monosynaptic retrograde spread of a genetically modifiable rabies virus. The technique is highly reliable, with transsynaptic labeling occurring in every electroporated neuron infected by the virus. Targeting single neocortical neuronal networks in vivo, we found clusters of both spiny and aspiny neurons surrounding the electroporated neuron in each case, in addition to intricately labeled distal cortical and subcortical inputs. This technique, broadly applicable for probing and manipulating single neuronal networks with single-cell resolution in vivo, may help shed new light on fundamental mechanisms underlying circuit development and information processing by neuronal networks throughout the brain.

  12. MicroRNA-370 directly targets FOXM1 to inhibit cell growth and metastasis in osteosarcoma cells.

    Science.gov (United States)

    Duan, Ning; Hu, Xiaojing; Yang, Xiaowei; Cheng, Huiguang; Zhang, Wentao

    2015-01-01

    MicroRNAs (miRNAs) are endogenous, non-coding, small RNAs, which play a critical role in regulating varieties of the biological and pathologic processes. Several reports have indicated that miR-370 acts as a tumor suppressor in varieties of tumors. However, the roles of miR-370 in osteosarcoma have not been reported. In this study, our objective was to explore the biological functions and its molecular mechanism of miR-370 in osteosarcoma cell lines, finding a therapeutic target of osteosarcoma. Our data demonstrated that miR-370 was evidently reduced in osteosarcoma cell lines, whereas FOXM1 expression was markedly increased. Up-regulation of miR-370 suppressed proliferation, arrested cell cycle and induced apoptosis in osteosarcoma cells. Besides, invasion and EMT of osteosarcoma cells was also inhibited by introduction of miR-370. Next, we found that FOXM1 expression was significantly reduced by up-regulation of miR-370. Bioinformatics analysis predicted that the FOXM1 was a potential target gene of miR-370. Luciferase reporter assay further confirmed that miR-370 could directly target the 3' UTR of FOXM1. Overexpression of FOXM1 in osteosarcoma cells transfected with miR-370 mimic partially reversed the effects of miR-370. In conclusion, miR-370 inhibited cell growth and metastasis in osteosarcoma cells by down-regulation of FOXM1.

  13. In Vivo Targeting of Antigens to Maturing Dendritic Cells via the DEC-205 Receptor Improves T Cell Vaccination

    Science.gov (United States)

    Bonifaz, Laura C.; Bonnyay, David P.; Charalambous, Anna; Darguste, Dara I.; Fujii, Shin-Ichiro; Soares, Helena; Brimnes, Marie K.; Moltedo, Bruno; Moran, Thomas M.; Steinman, Ralph M.

    2004-01-01

    The prevention and treatment of prevalent infectious diseases and tumors should benefit from improvements in the induction of antigen-specific T cell immunity. To assess the potential of antigen targeting to dendritic cells to improve immunity, we incorporated ovalbumin protein into a monoclonal antibody to the DEC-205 receptor, an endocytic receptor that is abundant on these cells in lymphoid tissues. Simultaneously, we injected agonistic α-CD40 antibody to mature the dendritic cells. We found that a single low dose of antibody-conjugated ovalbumin initiated immunity from the naive CD4+ and CD8+ T cell repertoire. Unexpectedly, the αDEC-205 antigen conjugates, given s.c., targeted to dendritic cells systemically and for long periods, and ovalbumin peptide was presented on MHC class I for 2 weeks. This was associated with stronger CD8+ T cell–mediated immunity relative to other forms of antigen delivery, even when the latter was given at a thousand times higher doses. In parallel, the mice showed enhanced resistance to an established rapidly growing tumor and to viral infection at a mucosal site. By better harnessing the immunizing functions of maturing dendritic cells, antibody-mediated antigen targeting via the DEC-205 receptor increases the efficiency of vaccination for T cell immunity, including systemic and mucosal resistance in disease models. PMID:15024047

  14. Nucleolin on the cell surface as a new molecular target for gastric cancer treatment.

    Science.gov (United States)

    Watanabe, Tatsuro; Hirano, Kazuya; Takahashi, Atsushi; Yamaguchi, Kensei; Beppu, Masatoshi; Fujiki, Hirota; Suganuma, Masami

    2010-01-01

    Nucleolin is an abundant non-ribosomal protein found in nucleolus and a major component of silver-stained nucleolar organizer region (AgNOR), a histopathological marker of cancer which is highly elevated in cancer cells. We recently reported that nucleolin on the cell surface of mouse gastric cancer cells acts as a receptor for tumor necrosis factor-alpha-inducing protein (Tipalpha), a new carcinogenic factor of Helicobacter pylori. In this study, we first examined the localization of nucleolin on cell surface of five gastric cancer cell lines by cell fractionation and flow cytometry: We found that large amounts of nucleolin were present on surface of MKN-45, KATOIII, MKN-74, and AGS cells, with smaller amounts on surface of MKN-1 cells. The membrane fraction of normal epithelial cells of mouse glandular stomach did not contain much nucleolin, suggesting that translocation of nucleolin to the cell surface occurs during carcinogenesis, making for easier binding with Tipalpha. AS1411, a nucleolin targeted DNA aptamer, inhibited growth of gastric cancer cell lines in this order of potency: MKN-45>KATOIII>AGS>MKN-74=MKN-1, associated with induction of S-phase cell cycle arrest. Fluorescein isothiocyanate (FITC)-AS1411 was more rapidly incorporated into MKN-45 and AGS than into MKN-1 cells, based on varying amounts of cell surface nucleolin. We think that AS1411 first binds to nucleolin on the cell surface and that the binding complex is then incorporated into the cells. All results indicate that nucleolin on the cell surface is a new and promising therapeutic target for treatment of gastric cancer.

  15. NFL-lipid nanocapsules for brain neural stem cell targeting in vitro and in vivo.

    Science.gov (United States)

    Carradori, Dario; Saulnier, Patrick; Préat, Véronique; des Rieux, Anne; Eyer, Joel

    2016-09-28

    The replacement of injured neurons by the selective stimulation of neural stem cells in situ represents a potential therapeutic strategy for the treatment of neurodegenerative diseases. The peptide NFL-TBS.40-63 showed specific interactions towards neural stem cells of the subventricular zone. The aim of our work was to produce a NFL-based drug delivery system able to target neural stem cells through the selective affinity between the peptide and these cells. NFL-TBS.40-63 (NFL) was adsorbed on lipid nanocapsules (LNC) whom targeting efficiency was evaluated on neural stem cells from the subventricular zone (brain) and from the central canal (spinal cord). NFL-LNC were incubated with primary neural stem cells in vitro or injected in vivo in adult rat brain (right lateral ventricle) or spinal cord (T10). NFL-LNC interactions with neural stem cells were different depending on the origin of the cells. NFL-LNC showed a preferential uptake by neural stem cells from the brain, while they did not interact with neural stem cells from the spinal cord. The results obtained in vivo correlate with the results observed in vitro, demonstrating that NFL-LNC represent a promising therapeutic strategy to selectively deliver bioactive molecules to brain neural stem cells.

  16. Targeting Netrin-1 in glioblastoma stem-like cells inhibits growth, invasion, and angiogenesis.

    Science.gov (United States)

    Sanvoranart, Tanwarat; Supokawej, Aungkura; Kheolamai, Pakpoom; U-Pratya, Yaowalak; Poungvarin, Niphon; Sathornsumetee, Sith; Issaragrisil, Surapol

    2016-11-01

    Glioblastoma (GBM) is an aggressive malignant brain tumor that still lacks effective therapy. Glioblastoma stem cells (GBM-SCs) were identified to contribute to aggressive phenotypes and poor clinical outcomes for GBM. Netrin-1, an axon guidance molecule, has been found in several tumors in adults. However, the role of Netrin-1 in GBM-SCs remains largely unknown. In this study, CD133-positive U251 GBM cells were used as a putative GBM-SC population to identify the functions of Netrin-1. Using lentiviral transduction, Netrin-1 miR RNAi vectors were transduced into CD133-positive U251 cells. We demonstrated that cell proliferation and survival were decreased following targeted deletion of Netrin-1. Cell invasion was dramatically diminished in Netrin-1 knockdown GBM-SCs. Moreover, Netrin-1 knockdown GBM-SCs exhibited less proangiogenic activity. In conclusion, Netrin-1 may represent a therapeutic target in glioblastoma.

  17. Dose-dependent regulation of target gene expression and cell proliferation by c-Myc levels.

    Science.gov (United States)

    Schuhmacher, Marino; Eick, Dirk

    2013-01-01

    The proto-oncogene c-myc encodes a basic helix-loop-helix leucine zipper transcription factor (c-Myc). c-Myc plays a crucial role in cell growth and proliferation. Here, we examined how expression of c-Myc target genes and cell proliferation depend on variation of c-Myc protein levels. We show that proliferation rates, the number of cells in S-phase, and cell size increased in a dose-dependent manner in response to increasing c-Myc levels. Likewise, the mRNA levels of c-Myc responsive genes steadily increased with rising c-Myc levels. Strikingly, steady-state mRNA levels of c-Myc target genes did not saturate even at highest c-Myc concentrations. These characteristics predestine c-Myc levels as a cellular rheostat for the control and fine-tuning of cell proliferation and growth rates.

  18. Zn(II)-curc targets p53 in thyroid cancer cells.

    Science.gov (United States)

    Garufi, Alessia; D'Orazi, Valerio; Crispini, Alessandra; D'Orazi, Gabriella

    2015-10-01

    TP53 mutation is a common event in many cancers, including thyroid carcinoma. Defective p53 activity promotes cancer resistance to therapies and a more malignant phenotype, acquiring oncogenic functions. Rescuing the function of mutant p53 (mutp53) protein is an attractive anticancer therapeutic strategy. Zn(II)-curc is a novel small molecule that has been shown to target mutp53 protein in several cancer cells, but its effect in thyroid cancer cells remains unclear. Here, we investigated whether Zn(II)-curc could affect p53 in thyroid cancer cells with both p53 mutation (R273H) and wild-type p53. Zn(II)-curc induced mutp53H273 downregulation and reactivation of wild-type functions, such as binding to canonical target promoters and target gene transactivation. This latter effect was similar to that induced by PRIMA-1. In addition, Zn(II)-curc triggered p53 target gene expression in wild-type p53-carrying cells. In combination treatments, Zn(II)-curc enhanced the antitumor activity of chemotherapeutic drugs, in both mutant and wild-type-carrying cancer cells. Taken together, our data indicate that Zn(II)-curc promotes the reactivation of p53 in thyroid cancer cells, providing in vitro evidence for a potential therapeutic approach in thyroid cancers.

  19. 1,25-Dihydroxyvitamin D/sub 3/ target cells in immature pancreatic islets

    Energy Technology Data Exchange (ETDEWEB)

    Clark, S.A.; Stumpf, W.E.; Sar, M.; DeLuca, H.F.

    1987-07-01

    Target cells of 1,25-dihydroxyvitamin D/sub 3/ were identified by autoradiography in islets from rats of different ages. Nuclei of pancreatic islet cells selectively concentrated 1,25-(/sup 3/H)dihydroxyvitamin D/sub 3/ but not 25-(/sup 3/H)hydroxyvitamin D/sub 3/ or 24,25-(/sup 3/H)dihydroxyvitamin D/sub 3/. Developmental studies of pancreatic islets indicated that target cells, as revealed by significant nuclear concentration of 1,25-(/sup 3/H)dihydroxyvitamin D/sub 3/, are present in islet cells of fetal rats. The percentage of islet cells that concentrated 1,25-(/sup 3/H)dihydroxyvitamin D/sub 3/ increased from 10 to 15% in the fetus to 60% at 1 day of age. Immunocytochemical staining indicated that insulin-containing cells but not glucagon or somatostatin cells concentrated 1,25-(/sup 3/H)dihydroxyvitamin D/sub 3/. Peak uptake of 1,25(/sup 3/H) dihydroxyvitamin D/sub 3/ was calculated to be 400 pmol/mg DNA, with no significant difference in nuclear accumulation between islets cells from neonatal and adult rats or between islets in vivo and isolated islets in vitro. The results of these studies indicate that (1) 1,25-(/sup 3/H)dihydroxyvitamin D/sub 3/ target cells are present in islets before pancreatic ..beta..-cells are morphologically or functionally mature; (2) islet ..beta..-cells concentrate 1,25-dihydroxyvitamin D/sub 3/, but not 25-hydroxyvitamin D/sub 3/ or 24,25-dihydroxyvitamin D/sub 3/. The authors conclude that only the 1,25-dihydroxyvitamin D/sub 3/ metabolite of vitamin D is accumulated by nuclei of developing and mature ..beta..-cells and suggest that 1,25-dihydroxyvitamin D/sub 3/ plays a role in the maturation of islet ..beta..-cells.

  20. microRNA-181b targets MLK2 in HL-60 cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    microRNAs(miRNAs) play critical roles in many different cellular processes,including metabolism,apoptosis,differentiation and development.We showed miR-181b to be highly expressed in acute myeloid leukemia(AML).Furthermore,miR-181b contributed to proliferation of AML cells by targeting MLK2.Our results demonstrated that miR-181b plays an important role in the biology of AML and may be useful in developing therapies targeting miRNAs.

  1. The Rho Target PRK2 Regulates Apical Junction Formation in Human Bronchial Epithelial Cells

    OpenAIRE

    Wallace, Sean W.; Magalhaes, Ana; Hall, Alan

    2010-01-01

    Rho GTPases regulate multiple signaling pathways to control a number of cellular processes during epithelial morphogenesis. To investigate the downstream pathways through which Rho regulates epithelial apical junction formation, we screened a small interfering RNA (siRNA) library targeting 28 known Rho target proteins in 16HBE human bronchial epithelial cells. This led to the identification of the serine-threonine kinase PRK2 (protein kinase C-related kinase 2, also called PKN2). Depletion of...

  2. Developing Novel Therapeutics Targeting Undifferentiated and Castration-Resistant Prostate Cancer Stem Cells

    Science.gov (United States)

    2015-10-01

    to identify PCSC-specific homing peptides; and 2) To perform unbiased drug library screening to identify novel PCSC-targeting chemicals. In the past...Specific Aim 2, we have finished a targeted library screening to identify several compounds that could sensitize the AR-PSA- LNCaP cells. We have also...peptide and finishing up screening and validating the kinase inhibitor library screening .

  3. T cells targeting NY-ESO-1 demonstrate efficacy against disseminated neuroblastoma

    OpenAIRE

    Singh, Nathan; Kulikovskaya, Irina; Barrett, David M.; Binder-Scholl, Gwendolyn; Jakobsen, Bent; Martinez, Daniel; Pawel, Bruce; June, Carl H.; Kalos, Michael D.; Grupp, Stephan A.

    2015-01-01

    The cancer-testis antigen NY-ESO-1 is expressed by many solid tumors and has limited expression by mature somatic tissues, making it a highly attractive target for tumor immunotherapy. Targeting NY-ESO-1 using engineered T cells has demonstrated clinical efficacy in the treatment of some adult tumors. Neuroblastoma is a significant cause of cancer mortality in children, and is a tumor type shown to be responsive to immunotherapies. We evaluated a large panel of primarily resected neuroblastom...

  4. A three-cell liquid hydrogen target for an extended focal plane polarimeter

    Energy Technology Data Exchange (ETDEWEB)

    Golovanov, L.B.; Borzounov, Yu.T.; Piskunov, N.M.; Tsvinev, A.P. [Joint Inst. for Nuclear Research, Dubna (Russian Federation). Lab. of High Energy; Ball, J.; Chesny, Ph.; Gheller, J.M.; Guillier, G.; Ladygin, V.P.; Theure, Ph.; Tomasi-Gustafsson, E. [Laboratoire National Saturne, Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France)

    1996-12-31

    This article describes the design and working principle of a 3-cell liquid hydrogen target produced for the high-energy deuteron polarimeter HYPOM. This target uses liquid Helium as a cooling agent. After a general description of the apparatus, tests and operating modes are thoroughly explained. In particular the air controlled self regulation of Helium flow in the cryostat to stabilize the liquid hydrogen level is presented. (author). 12 refs.; Submitted to Nuclear Instruments and Methods, A (NL).

  5. Effective Binding of a Phosphatidylserine-Targeting Antibody to Ebola Virus Infected Cells and Purified Virions

    Science.gov (United States)

    Dowall, S. D.; Graham, V. A.; Corbin-Lickfett, K.; Empig, C.; Schlunegger, K.; Bruce, C. B.; Easterbrook, L.; Hewson, R.

    2015-01-01

    Ebola virus is responsible for causing severe hemorrhagic fevers, with case fatality rates of up to 90%. Currently, no antiviral or vaccine is licensed against Ebola virus. A phosphatidylserine-targeting antibody (PGN401, bavituximab) has previously been shown to have broad-spectrum antiviral activity. Here, we demonstrate that PGN401 specifically binds to Ebola virus and recognizes infected cells. Our study provides the first evidence of phosphatidylserine-targeting antibody reactivity against Ebola virus. PMID:25815346

  6. Effective Binding of a Phosphatidylserine-Targeting Antibody to Ebola Virus Infected Cells and Purified Virions

    Directory of Open Access Journals (Sweden)

    S. D. Dowall

    2015-01-01

    Full Text Available Ebola virus is responsible for causing severe hemorrhagic fevers, with case fatality rates of up to 90%. Currently, no antiviral or vaccine is licensed against Ebola virus. A phosphatidylserine-targeting antibody (PGN401, bavituximab has previously been shown to have broad-spectrum antiviral activity. Here, we demonstrate that PGN401 specifically binds to Ebola virus and recognizes infected cells. Our study provides the first evidence of phosphatidylserine-targeting antibody reactivity against Ebola virus.

  7. Obtaining control of cell surface functionalizations via Pre-targeting and Supramolecular host guest interactions.

    Science.gov (United States)

    Rood, Mark T M; Spa, Silvia J; Welling, Mick M; Ten Hove, Jan Bart; van Willigen, Danny M; Buckle, Tessa; Velders, Aldrik H; van Leeuwen, Fijs W B

    2017-01-06

    The use of mammalian cells for therapeutic applications is finding its way into modern medicine. However, modification or "training" of cells to make them suitable for a specific application remains complex. By envisioning a chemical toolbox that enables specific, but straight-forward and generic cellular functionalization, we investigated how membrane-receptor (pre)targeting could be combined with supramolecular host-guest interactions based on β-cyclodextrin (CD) and adamantane (Ad). The feasibility of this approach was studied in cells with membranous overexpression of the chemokine receptor 4 (CXCR4). By combining specific targeting of CXCR4, using an adamantane (Ad)-functionalized Ac-TZ14011 peptide (guest; KD = 56 nM), with multivalent host molecules that entailed fluorescent β-CD-Poly(isobutylene-alt-maleic-anhydride)-polymers with different fluorescent colors and number of functionalities, host-guest cell-surface modifications could be studied in detail. A second set of Ad-functionalized entities enabled introduction of additional surface functionalities. In addition, the attraction between CD and Ad could be used to drive cell-cell interactions. Combined we have shown that supramolecular interactions, that are based on specific targeting of an overexpressed membrane-receptor, allow specific and stable, yet reversible, surface functionalization of viable cells and how this approach can be used to influence the interaction between cells and their surroundings.

  8. Adenanthin targets peroxiredoxin I/II to kill hepatocellular carcinoma cells.

    Science.gov (United States)

    Hou, J-K; Huang, Y; He, W; Yan, Z-W; Fan, L; Liu, M-H; Xiao, W-L; Sun, H-D; Chen, G-Q

    2014-09-04

    Adenanthin, a natural diterpenoid isolated from the leaves of Isodon adenanthus, has recently been reported to induce leukemic cell differentiation by targeting peroxiredoxins (Prx) I and II. On the other hand, increasing lines of evidence propose that these Prx proteins would become potential targets to screen drugs for the prevention and treatment of solid tumors. Therefore, it is of significance to explore the potential activities of adenanthin on solid tumor cells. Here, we demonstrate that Prx I protein is essential for the survival of hepatocellular carcinoma (HCC) cells, and adenanthin can kill these malignant liver cells in vitro and xenografts. We also show that the cell death-inducing activity of adenanthin on HCC cells is mediated by the increased reactive oxygen species (ROS) levels. Furthermore, the silencing of Prx I or Prx II significantly enhances the cytotoxic activity of adenanthin on HCC, whereas the ectopic expression of Prx I and Prx II but not their mutants of adenanthin-bound cysteines can rescue adenanthin-induced cytotoxicity in Prxs-silenced HCC cells. Taken together, our results propose that adenanthin targets Prx I/II to kill HCC cells and its therapeutic significance warrants to be further explored in HCC patients.

  9. CD133-targeted gene transfer into long-term repopulating hematopoietic stem cells.

    Science.gov (United States)

    Brendel, Christian; Goebel, Benjamin; Daniela, Abriss; Brugman, Martijn; Kneissl, Sabrina; Schwäble, Joachim; Kaufmann, Kerstin B; Müller-Kuller, Uta; Kunkel, Hana; Chen-Wichmann, Linping; Abel, Tobias; Serve, Hubert; Bystrykh, Leonid; Buchholz, Christian J; Grez, Manuel

    2015-01-01

    Gene therapy for hematological disorders relies on the genetic modification of CD34(+) cells, a heterogeneous cell population containing about 0.01% long-term repopulating cells. Here, we show that the lentiviral vector CD133-LV, which uses a surface marker on human primitive hematopoietic stem cells (HSCs) as entry receptor, transfers genes preferentially into cells with high engraftment capability. Transduction of unstimulated CD34(+) cells with CD133-LV resulted in gene marking of cells with competitive proliferative advantage in vitro and in immunodeficient mice. The CD133-LV-transduced population contained significantly more cells with repopulating capacity than cells transduced with vesicular stomatitis virus (VSV)-LV, a lentiviral vector pseudotyped with the vesicular stomatitis virus G protein. Upon transfer of a barcode library, CD133-LV-transduced cells sustained gene marking in vivo for a prolonged period of time with a 6.7-fold higher recovery of barcodes compared to transduced control cells. Moreover, CD133-LV-transduced cells were capable of repopulating secondary recipients. Lastly, we show that this targeting strategy can be used for transfer of a therapeutic gene into CD34(+) cells obtained from patients suffering of X-linked chronic granulomatous disease. In conclusion, direct gene transfer into CD133(+) cells allows for sustained long-term engraftment of gene corrected cells.

  10. A combination of trastuzumab and BAG-1 inhibition synergistically targets HER2 positive breast cancer cells.

    Science.gov (United States)

    Papadakis, Emmanouil; Robson, Natalia; Yeomans, Alison; Bailey, Sarah; Laversin, Stephanie; Beers, Stephen; Sayan, A Emre; Ashton-Key, Margaret; Schwaiger, Stefan; Stuppner, Hermann; Troppmair, Jakob; Packham, Graham; Cutress, Ramsey

    2016-04-05

    Treatment of HER2+ breast cancer with trastuzumab is effective and combination anti-HER2 therapies have demonstrated benefit over monotherapy in the neoadjuvant and metastatic settings. This study investigated the therapeutic potential of targeting the BAG-1 protein co-chaperone in trastuzumab-responsive or -resistant cells. In the METABRIC dataset, BAG-1 mRNA was significantly elevated in HER2+ breast tumors and predicted overall survival in a multivariate analysis (HR = 0.81; p = 0.022). In a breast cell line panel, BAG-1 protein was increased in HER2+ cells and was required for optimal growth as shown by siRNA knockdown. Overexpression of BAG-1S in HER2+ SKBR3 cells blocked growth inhibition by trastuzumab, whereas overexpression of a mutant BAG-1S protein (BAG-1S H3AB), defective in binding HSC70, potentiated the effect of trastuzumab. Injection of a Tet-On SKBR3 clone, induced to overexpress myc-BAG-1S into the mammary fat pads of immunocompromised mice, resulted in 2-fold larger tumors compared to uninduced controls. Induction of myc-BAG-1S expression in two Tet-On SKBR3 clones attenuated growth inhibition by trastuzumab in vitro. Targeting endogenous BAG-1 by siRNA enhanced growth inhibition of SKBR3 and BT474 cells by trastuzumab, while BAG-1 protein-protein interaction inhibitor (Thio-S or Thio-2) plus trastuzumab combination treatment synergistically attenuated growth. In BT474 cells this reduced protein synthesis, caused G1/S cell cycle arrest and targeted the ERK and AKT signaling pathways. In a SKBR3 subpopulation with acquired resistance to trastuzumab BAG-1 targeting remained effective and either Thio-2 or BAG-1 siRNA reduced growth more compared to trastuzumab-responsive parental cells. In summary, targeting BAG-1 function in combination with anti-HER2 therapy might prove beneficial.

  11. Targeted Germline Modifications in Rats Using CRISPR/Cas9 and Spermatogonial Stem Cells

    Directory of Open Access Journals (Sweden)

    Karen M. Chapman

    2015-03-01

    Full Text Available Organisms with targeted genomic modifications are efficiently produced by gene editing in embryos using CRISPR/Cas9 RNA-guided DNA endonuclease. Here, to facilitate germline editing in rats, we used CRISPR/Cas9 to catalyze targeted genomic mutations in rat spermatogonial stem cell cultures. CRISPR/Cas9-modified spermatogonia regenerated spermatogenesis and displayed long-term sperm-forming potential following transplantation into rat testes. Targeted germline mutations in Epsti1 and Erbb3 were vertically transmitted from recipients to exclusively generate “pure,” non-mosaic mutant progeny. Epsti1 mutant rats were produced with or without genetic selection of donor spermatogonia. Monoclonal enrichment of Erbb3 null germlines unmasked recessive spermatogenesis defects in culture that were buffered in recipients, yielding mutant progeny isogenic at targeted alleles. Thus, spermatogonial gene editing with CRISPR/Cas9 provided a platform for generating targeted germline mutations in rats and for studying spermatogenesis.

  12. Drug delivery using nanoparticles for cancer stem-like cell targeting

    Directory of Open Access Journals (Sweden)

    Bing eLu

    2016-04-01

    Full Text Available The theory of cancer stem-like cell (or cancer stem cell, CSC has been established to explain how tumor heterogeneity arises and contributes to tumor progression in diverse cancer types. CSCs are believed to drive tumor growth and elicit resistance to conventional therapeutics. Therefore, CSCs are becoming novel target in both medical researches and clinical studies. Emerging evidences showed that nanoparticles effectively inhibit many types of CSCs by targeting various specific markers (aldehyde dehydrogenases, CD44, CD90, and CD133 and signaling pathways (Notch, Hedgehog, and TGF-β, which are critically involved in CSC function and maintenance. In this review, we briefly summarize the current status of CSC research and review a number of state-of-the-art nanomedicine approaches targeting CSC. In addition, we discuss emerging therapeutic strategies using epigenetic drugs to eliminate CSCs and inhibit cancer cell reprogramming.

  13. Therapeutic potential of mTOR inhibitors for targeting cancer stem cells.

    Science.gov (United States)

    Francipane, Maria Giovanna; Lagasse, Eric

    2016-11-01

    The mammalian target of rapamycin (mTOR) pathway is aberrantly activated in many cancer types. As the intricate network of regulatory mechanisms controlling mTOR activity is uncovered, more refined drugs are designed and tested in clinical trials. While first generation mTOR inhibitors have failed to show clinical efficacy due partly to the feedback relief of oncogenetic circuits, newly developed inhibitors show greater promise as anti-cancer agents. An effective drug must defeat the cancer stem cells (CSCs) while sparing the normal stem cells. Due to its opposing role on normal and malignant stem cells, mTOR lends itself very well as a therapeutic target. Indeed, a preferential inhibitory effect on CSCs has already been shown for some mTOR inhibitors. These results provide a compelling rationale for the clinical development of mTOR-targeted therapies.

  14. Stopping cancer in its tracks: using small molecular inhibitors to target glioblastoma migrating cells.

    Science.gov (United States)

    Mattox, Austin K; Li, Jing; Adamson, David C

    2012-12-01

    Glioblastoma multiforme (GBM) represents one of the most common aggressive types of primary brain tumors. Despite advances in surgical resection, novel neuroimaging procedures, and the most recent adjuvant radiotherapy and chemotherapy, the median survival after diagnosis is about 12-14 months. Targeting migrating GBM cells is a key research strategy in the fight against this devastating cancer. Though the vast majority of the primary tumor focus can be surgically resected, these migrating cells are responsible for its universal recurrence. Numerous strategies and technologies are being explored to target migrating glioma cells, with small molecular inhibitors as one of the most commonly studied. Small molecule inhibitors, such as protein kinase inhibitors, phosphorylation site inhibitors, protease inhibitors, and antisense oligonucleotides show promise in slowing the progression of this disease. A better understanding of these small molecule inhibitors and how they target various extra- and intracellular signaling pathways may eventually lead to a cure for GBM.

  15. Targeting EGFR-overexpressed A431 cells with EGF-labeled silica-coated magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Kralj, Slavko, E-mail: slavko.kralj@ijs.si [Jozef Stefan Institute, Department for Materials Synthesis (Slovenia); Rojnik, Matija; Kos, Janko [University of Ljubljana, Faculty of Pharmacy (Slovenia); Makovec, Darko [Jozef Stefan Institute, Department for Materials Synthesis (Slovenia)

    2013-05-15

    Human epidermal growth-factor receptor (EGFR) has emerged as an attractive target for cancer therapy. In this study, amino- or carboxyl-functionalized silica-coated maghemite nanoparticles were conjugated with epidermal growth-factor (EGF) using five different binding modes: carbodiimide chemistry, two types of homo-bifunctional cross-linking reagents, and electrostatic interactions between the nanoparticles and the EGF. The nanoparticles and their aqueous suspensions were characterized by transmission electron microscopy, zeta-potential measurements and dynamic light scattering. The binding efficiency of the EGF to the nanoparticles was measured by flow cytometry using a specific anti-EGF antibody. The ability of EGF bioconjugates to target the EGF receptors was tested using EGFR over-expressing A431 cells in comparison to EGFR negative HeLa cells. Our results showed that the bioconjugates where the EGF was bonded by carbodiimide chemistry are the most effective for the specific targeting of EGFR-expressing cells in vitro.

  16. Facile Synthesis of Biocompatible Fluorescent Nanoparticles for Cellular Imaging and Targeted Detection of Cancer Cells.

    Science.gov (United States)

    Tang, Fu; Wang, Chun; Wang, Xiaoyu; Li, Lidong

    2015-11-18

    In this work, we report the facile synthesis of functional core-shell structured nanoparticles with fluorescence enhancement, which show specific targeting of cancer cells. Biopolymer poly-l-lysine was used to coat the silver core with various shell thicknesses. Then, the nanoparticles were functionalized with folic acid as a targeting agent for folic acid receptor. The metal-enhanced fluorescence effect was observed when the fluorophore (5-(and-6)-carboxyfluorescein-succinimidyl ester) was conjugated to the modified nanoparticle surface. Cellular imaging assay of the nanoparticles in folic acid receptor-positive cancer cells showed their excellent biocompatibility and selectivity. The as-prepared functional nanoparticles demonstrate the efficiency of the metal-enhanced fluorescence effect and provide an alternative approach for the cellular imaging and targeting of cancer cells.

  17. A novel murine T-cell receptor targeting NY-ESO-1.

    Science.gov (United States)

    Rosati, Shannon F; Parkhurst, Maria R; Hong, Young; Zheng, Zhili; Feldman, Steven A; Rao, Mahadev; Abate-Daga, Daniel; Beard, Rachel E; Xu, Hui; Black, Mary A; Robbins, Paul F; Schrump, David A; Rosenberg, Steven A; Morgan, Richard A

    2014-04-01

    Cancer testis antigens, such as NY-ESO-1, are expressed in a variety of prevalent tumors and represent potential targets for T-cell receptor (TCR) gene therapy. DNA encoding a murine anti-NY-ESO-1 TCR gene (mTCR) was isolated from immunized HLA-A*0201 transgenic mice and inserted into a γ-retroviral vector. Two mTCR vectors were produced and used to transduce human PBL. Transduced cells were cocultured with tumor target cell lines and T2 cells pulsed with the NY-ESO-1 peptide, and assayed for cytokine release and cell lysis activity. The most active TCR construct was selected for production of a master cell bank for clinical use. mTCR-transduced PBL maintained TCR expression in short-term and long-term culture, ranging from 50% to 90% efficiency 7-11 days after stimulation and 46%-82% 10-20 days after restimulation. High levels of interferon-γ secretion were observed (1000-12000 pg/mL), in tumor coculture assays and recognition of peptide-pulsed cells was observed at 0.1 ng/mL, suggesting that the new mTCR had high avidity for antigen recognition. mTCR-transduced T cells also specifically lysed human tumor targets. In all assays, the mTCR was equivalent or better than the comparable human TCR. As the functional activity of TCR-transduced cells may be affected by the formation of mixed dimers, mTCRs, which are less likely to form mixed dimers with endogenous hTCRs, may be more effective in vivo. This new mTCR targeted to NY-ESO-1 represents a novel potential therapeutic option for adoptive cell-transfer therapy for a variety of malignancies.

  18. Enhancement of antibody-dependent mechanisms of tumor cell lysis by a targeted activator of complement.

    Science.gov (United States)

    Imai, Masaki; Ohta, Rieko; Varela, Juan C; Song, Hongbin; Tomlinson, Stephen

    2007-10-01

    Complement inhibitors expressed on tumor cells provide a hindrance to the therapeutic efficacy of some monoclonal antibodies (mAb). We investigated a novel strategy to overwhelm complement inhibitor activity and amplify complement activation on tumor cells. The C3-binding domain of human complement receptor 2 (CR2; CD21) was linked to the complement-activating Fc region of human IgG1 (CR2-Fc), and the ability of the construct to target and amplify complement deposition on tumor cells was investigated. CR2 binds C3 activation fragments, and CR2-Fc targeted tumor cells by binding to C3 initially deposited by a tumor-specific antibody. Complement deposition on Du145 cells (human prostate cancer cell line) and anti-MUC1 mAb-mediated complement-dependent lysis of Du145 cells were significantly enhanced by CR2-Fc. Anti-MUC1 antibody-dependent cell-mediated cytotoxicity of Du145 by human peripheral blood mononuclear cells was also significantly enhanced by CR2-Fc in both the presence and the absence of complement. Radiolabeled CR2-Fc targeted to s.c. Du145 tumors in nude mice treated with anti-MUC1 mAb, validating the targeting strategy in vivo. A metastatic model was used to investigate the effect of CR2-Fc in a therapeutic paradigm. Administration of CR2-Fc together with mAb therapy significantly improved long-term survival of nude mice challenged with an i.v. injection of EL4 cells. The data show that CR2-Fc enhances the therapeutic efficacy of antibody therapy, and the construct may provide particular benefits under conditions of limiting antibody concentration or low tumor antigen density.

  19. Advances of Driver Gene and Targeted Therapy of Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Dan ZHANG

    2014-10-01

    Full Text Available Lung cancer is the leading cause of cancer-related mortality in the worldwide. The discovery of drive gene makes tumor treatment is no longer "one-size-fits-all". Targeted therapy to change the present situation of cancer drugs become "bullet" with eyes, the effect is visible and bring a revolution in the treatment of lung cancer. The diver gene and targeted therapy have became the new cedule of non-small cell lung cancer (NSCLC. Society of Clinical Oncology (ASCO has showed 11 kinds of diver genes. Here, we review the functional and structural characteristics and the targeted therapy in the 11 kinds of driver gene mutations.

  20. [Advances of driver gene and targeted therapy of non-small cell lung cancer].

    Science.gov (United States)

    Zhang, Dan; Huang, Yan; Wang, Hongyang

    2014-10-20

    Lung cancer is the leading cause of cancer-related mortality in the worldwide. The discovery of drive gene makes tumor treatment is no longer "one-size-fits-all". Targeted therapy to change the present situation of cancer drugs become "bullet" with eyes, the effect is visible and bring a revolution in the treatment of lung cancer. The diver gene and targeted therapy have became the new cedule of non-small cell lung cancer (NSCLC). Society of Clinical Oncology (ASCO) has showed 11 kinds of diver genes. Here, we review the functional and structural characteristics and the targeted therapy in the 11 kinds of driver gene mutations.

  1. Cell-specific RNA aptamer against human CCR5 specifically targets HIV-1 susceptible cells and inhibits HIV-1 infectivity.

    Science.gov (United States)

    Zhou, Jiehua; Satheesan, Sangeetha; Li, Haitang; Weinberg, Marc S; Morris, Kevin V; Burnett, John C; Rossi, John J

    2015-03-19

    The C-C chemokine receptor type 5 (CCR5) is a receptor expressed by T cells and macrophages that serves as a coreceptor for macrophage-tropic HIV-1. Loss of CCR5 is associated with resistance to HIV-1. Here, we combine the live-cell-based SELEX with high-throughput sequencing technology to generate CCR5 RNA aptamers capable of specifically targeting HIV-1 susceptible cells (as small interfering RNA [siRNA] delivery agent) and inhibiting HIV-1 infectivity (as antiviral agent) via block of the CCR5 required for HIV-1 to enter cells. One of the best candidates, G-3, efficiently bound and was internalized into human CCR5-expressing cells. The G-3 specifically neutralized R5 virus infection in primary peripheral blood mononuclear cells, and in vivo generated human CD4(+) T cells with a nanomolar inhibitory concentration 50%. G-3 was also capable of transferring functional siRNAs to CCR5-expressing cells. Collectively, the cell-specific, internalizing, CCR5-targeted aptamers and aptamer-siRNA conjugates offer promise for overcoming some of the current challenges of drug resistance in HIV-1 by providing cell-type- or tissue-specific delivery of various therapeutic moieties.

  2. Participation of CD45, NKR-P1A and ANK61 antigen in rat hepatic NK cell (pit cell)-mediated target cell cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    Dian Zhong Luo; David Vermijlen; B lent Ahishali; Vasilis Triantis; Eddie Wisse; Karin Vanderkerken; Peter J.K. Kuppen

    2000-01-01

    AIM Several triggering receptors have been described to be involved in natural killer (NK) cellmediated target cytotoxicity. In these studies, NK cells derived from blood or spleen were used. Pit cells are liver-specific NK cells that possess a higher level of natural cytotoxicity and a different morphology when compared to blood NK cells. The aim of this study was to characterize the role of the NK-triggering molecules NKR-P1A, ANK61 antigen, and CD45 in pit cell-mediated killing of target cells. METHODS 51 Cr-release and DNA fragmentation were used to quantify target cell lysis and apoptosis, respectively. RESULTS Flow cytometric analysis showed that pit cells expressed CD45, NKR-P1A, and ANK61 antigen. Treatment of pit cells with monoclonal antibody ( mAb ) to CD45 ( ANK74 ) not only inhibited CC531s or YAC-1 target lysis but also apoptosis induced by pit cells. The mAbs to NKRP1A (3.2.3) and ANK61 antigen (ANK61) had no effect on pit cell-mediated CC531s or YAC-1 target cytolysis or apoptosis, while they did increase the Fcγ receptor positive (FcγR+) P815 cytolysis and apoptosis. This enhanced cytotoxicity could he inhibited by 3,4-dichloroisocoumarin, an inhibitor of granzymes. CONCLUSION These results indicate that CD45 participates in pit cell-mediated CC531s and YAC-1 target cytolysis and apoptosis. NKR-P1A and ANK61 antigen on pit cells function as activation structures against FcγR+ P815 cells, which was mediated by the perforin/granzyme pathway.

  3. Identification of cell-specific targets of sumoylation during mouse spermatogenesis.

    Science.gov (United States)

    Xiao, Yuxuan; Pollack, Daniel; Andrusier, Miriam; Levy, Avi; Callaway, Myrasol; Nieves, Edward; Reddi, Prabhakara; Vigodner, Margarita

    2016-02-01

    Recent findings suggest diverse and potentially multiple roles of small ubiquitin-like modifier (SUMO) in testicular function and spermatogenesis. However, SUMO targets remain uncharacterized in the testis due to the complex multicellular nature of testicular tissue, the inability to maintain and manipulate spermatogenesis in vitro, and the technical challenges involved in identifying low-abundance endogenous SUMO targets. In this study, we performed cell-specific identification of sumoylated proteins using concentrated cell lysates prepared with de-sumoylation inhibitors from freshly purified spermatocytes and spermatids. One-hundred and twenty proteins were uniquely identified in the spermatocyte and/or spermatid fractions. The identified proteins are involved in the regulation of transcription, stress response, microRNA biogenesis, regulation of major enzymatic pathways, nuclear-cytoplasmic transport, cell-cycle control, acrosome biogenesis, and other processes. Several proteins with important roles during spermatogenesis were chosen for further characterization by co-immunoprecipitation, co-localization, and in vitro sumoylation studies. GPS-SUMO Software was used to identify consensus and non-consensus sumoylation sites within the amino acid sequences of the proteins. The analyses confirmed the cell-specific sumoylation and/or SUMO interaction of several novel, previously uncharacterized SUMO targets such as CDK1, RNAP II, CDC5, MILI, DDX4, TDP-43, and STK31. Furthermore, several proteins that were previously identified as SUMO targets in somatic cells (KAP1 and MDC1) were identified as SUMO targets in germ cells. Many of these proteins have a unique role in spermatogenesis and during meiotic progression. This research opens a novel avenue for further studies of SUMO at the level of individual targets.

  4. Angiopep-2 and activatable cell penetrating peptide dual modified nanoparticles for enhanced tumor targeting and penetrating.

    Science.gov (United States)

    Mei, Ling; Zhang, Qianyu; Yang, Yuting; He, Qin; Gao, Huile

    2014-10-20

    Delivering chemotherapeutics by nanoparticles into tumor was influenced by at least two factors: specific targeting and highly efficient penetrating of the nanoparticles. In this study, two targeting ligands, angiopep-2 and activatable cell penetrating peptide (ACP), were functionalized onto nanoparticles for tumor targeting delivery. In this system, angiopep-2 is a ligand of low-density lipoprotein receptor-related protein-1 (LRP1) which was highly expressed on tumor cells, and the ACP was constructed by the conjugation of RRRRRRRR (R8) with EEEEEEEE through a matrix metalloproteinase-2 (MMP-2) sensitive linker, enabling the ACP with tumor microenvironment-responsive cell penetrating property. 4h incubation of ACP with MMP-2 leads to over 80% cleavage of ACP, demonstrating ACP indeed possessed MMP-2 responsive property. The constructed dual targeting nanoparticles (AnACNPs) were approximately 110 nm with a polydispersity index of 0.231. In vitro, ACP modification and angiopep-2 modification could both enhance the U-87 MG cell uptake because of the high expression of MMP-2 and LRP-1 on C6 cells. AnACNPs showed higher uptake level than the single ligand modified nanoparticles. The uptake of all particles was time- and concentration-dependent and endosomes were involved. In vivo, AnACNPs showed best tumor targeting efficiency. The distribution of AnACNPs in tumor was higher than all the other particles. After microvessel staining with anti-CD31 antibody, the fluorescent distribution demonstrated AnACNPs could distribute in the whole tumor with the highest intensity. In conclusion, a novel drug delivery system was developed for enhanced tumor dual targeting and elevated cell internalization.

  5. Identification of cell-specific targets of sumoylation during mouse spermatogenesis

    Science.gov (United States)

    Xiao, Yuxuan; Pollack, Daniel; Andrusier, Miriam; Levy, Avi; Callaway, Myrasol; Nieves, Edward; Reddi, Prabhakara; Vigodner, Margarita

    2015-01-01

    Recent findings suggest diverse and potentially multiple roles of SUMO in testicular function and spermatogenesis. However, SUMO targets remain uncharacterized in the testis due to the complex multicellular nature of testicular tissue, the inability to maintain and manipulate spermatogenesis in vitro, and the technical challenges involved in identifying low-abundance endogenous SUMO targets. In this study, we performed cell-specific identification of sumoylated proteins using concentrated cell lysates prepared with de-sumoylation inhibitors from freshly purified spermatocytes and spermatids. One-hundred and twenty proteins were uniquely identified in the spermatocyte and/or spermatid fractions. The identified proteins are involved in the regulation of transcription, stress response, microRNA biogenesis, regulation of major enzymatic pathways, nuclear-cytoplasmic transport, cell cycle control, acrosome biogenesis, and other processes. Several proteins with important roles during spermatogenesis were chosen for further characterization by co-immunoprecipitation, co-localization and in-vitro sumoylation studies. GPS-SUMO software was used to identify consensus and non-consensus sumoylation sites within the amino acid sequences of the proteins. The analyses confirmed the cell-specific sumoylation and/or SUMO interaction of several novel, previously uncharacterized SUMO targets such as CDK1, RNAP II, CDC5, MILI, DDX4, TDP-43 and STK31. Furthermore, several proteins that were previously identified as SUMO targets in somatic cells (e.g., KAP1, MDC1) were identified as SUMO targets in germ cells. Many of these proteins have a unique role in spermatogenesis and during meiotic progression. This research opens a novel avenue for further studies of SUMO at the level of individual targets. PMID:26701181

  6. Identification and Regulation of c-Myb Target Genes in MCF-7 Cells

    Directory of Open Access Journals (Sweden)

    O'Rourke John P

    2011-01-01

    Full Text Available Abstract Background The c-Myb transcription factor regulates differentiation and proliferation in hematopoietic cells, stem cells and epithelial cells. Although oncogenic versions of c-Myb were first associated with leukemias, over expression or rearrangement of the c-myb gene is common in several types of solid tumors, including breast cancers. Expression of the c-myb gene in human breast cancer cells is dependent on estrogen stimulation, but little is known about the activities of the c-Myb protein or what genes it regulates in estrogen-stimulated cells. Methods We used chromatin immunoprecipitation coupled with whole genome promoter tiling microarrays to identify endogenous c-Myb target genes in human MCF-7 breast cancer cells and characterized the activity of c-Myb at a panel of target genes during different stages of estrogen deprivation and stimulation. Results By using different antibodies and different growth conditions, the c-Myb protein was found associated with over 10,000 promoters in MCF-7 cells, including many genes that encode cell cycle regulators or transcription factors and more than 60 genes that encode microRNAs. Several previously identified c-Myb target genes were identified, including CCNB1, MYC and CXCR4 and novel targets such as JUN, KLF4, NANOG and SND1. By studying a panel of these targets to validate the results, we found that estradiol stimulation triggered the association of c-Myb with promoters and that association correlated with increased target gene expression. We studied one target gene, CXCR4, in detail, showing that c-Myb associated with the CXCR4 gene promoter and activated a CXCR4 reporter gene in transfection assays. Conclusions Our results show that c-Myb associates with a surprisingly large number of promoters in human cells. The results also suggest that estradiol stimulation leads to large-scale, genome-wide changes in c-Myb activity and subsequent changes in gene expression in human breast cancer

  7. Stanniocalcin-2 is a HIF-1 target gene that promotes cell proliferation in hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Law, Alice Y.S. [Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong); Wong, Chris K.C., E-mail: ckcwong@hkbu.edu.hk [Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong)

    2010-02-01

    Stanniocalcin-2 (STC2), the paralog of STC1, has been suggested as a novel target of oxidative stress response to protect cells from apoptosis. The expression of STC2 has been reported to be highly correlated with human cancer development. In this study, we reported that STC2 is a HIF-1 target gene and is involved in the regulation of cell proliferation. STC2 was shown to be up-regulated in different breast and ovarian cancer cells, following exposure to hypoxia. Using ovarian cancer cells (SKOV3), the underlying mechanism of HIF-1 mediated STC2 gene transactivation was characterized. Hypoxia-induced STC2 expression was found to be HIF-1{alpha} dependent and required the recruitment of p300 and HDAC7. Using STC2 promoter deletion constructs and site-directed mutagenesis, two authentic consensus HIF-1 binding sites were identified. Under hypoxic condition, the silencing of STC2 reduced while the overexpression of STC2 increased the levels of phosphorylated retinoblastoma and cyclin D in both SKOV3 and MCF7 cells. The change in cell cycle proteins correlated with the data of the serial cell counts. The results indicated that cell proliferation was reduced in STC2-silenced cells but was increased in STC2-overexpressing hypoxic cells. Solid tumor progression is usually associated with hypoxia. The identification and functional analysis of STC2 up-regulation by hypoxia, a feature of the tumor microenvironment, sheds light on a possible role for STC2 in tumors.

  8. Immunization of stromal cell targeting fibroblast activation protein providing immunotherapy to breast cancer mouse model.

    Science.gov (United States)

    Meng, Mingyao; Wang, Wenju; Yan, Jun; Tan, Jing; Liao, Liwei; Shi, Jianlin; Wei, Chuanyu; Xie, Yanhua; Jin, Xingfang; Yang, Li; Jin, Qing; Zhu, Huirong; Tan, Weiwei; Yang, Fang; Hou, Zongliu

    2016-08-01

    Unlike heterogeneous tumor cells, cancer-associated fibroblasts (CAF) are genetically more stable which serve as a reliable target for tumor immunotherapy. Fibroblast activation protein (FAP) which is restrictively expressed in tumor cells and CAF in vivo and plays a prominent role in tumor initiation, progression, and metastasis can function as a tumor rejection antigen. In the current study, we have constructed artificial FAP(+) stromal cells which mimicked the FAP(+) CAF in vivo. We immunized a breast cancer mouse model with FAP(+) stromal cells to perform immunotherapy against FAP(+) cells in the tumor microenvironment. By forced expression of FAP, we have obtained FAP(+) stromal cells whose phenotype was CD11b(+)/CD34(+)/Sca-1(+)/FSP-1(+)/MHC class I(+). Interestingly, proliferation capacity of the fibroblasts was significantly enhanced by FAP. In the breast cancer-bearing mouse model, vaccination with FAP(+) stromal cells has significantly inhibited the growth of allograft tumor and reduced lung metastasis indeed. Depletion of T cell assays has suggested that both CD4(+) and CD8(+) T cells were involved in the tumor cytotoxic immune response. Furthermore, tumor tissue from FAP-immunized mice revealed that targeting FAP(+) CAF has induced apoptosis and decreased collagen type I and CD31 expression in the tumor microenvironment. These results implicated that immunization with FAP(+) stromal cells led to the disruption of the tumor microenvironment. Our study may provide a novel strategy for immunotherapy of a broad range of cancer.

  9. Genome-wide mapping of Polycomb target genes unravels their roles in cell fate transitions

    DEFF Research Database (Denmark)

    Bracken, Adrian P; Dietrich, Nikolaj; Pasini, Diego;

    2006-01-01

    The Polycomb group (PcG) proteins form chromatin-modifying complexes that are essential for embryonic development and stem cell renewal and are commonly deregulated in cancer. Here, we identify their target genes using genome-wide location analysis in human embryonic fibroblasts. We find that Pol......The Polycomb group (PcG) proteins form chromatin-modifying complexes that are essential for embryonic development and stem cell renewal and are commonly deregulated in cancer. Here, we identify their target genes using genome-wide location analysis in human embryonic fibroblasts. We find...

  10. Targeted therapy for cytokine-refractory metastatic renal cell carcinoma, and treatment in the community.

    Science.gov (United States)

    Bukowski, Ronald M

    2006-05-01

    This report of a case of cytokine-refractory metastatic, clear-cell renal cell carcinoma (RCC) presents some current issues related to use of targeted therapy in the community. Due to the different mechanisms of cytostatic vs. cytotoxic agents, traditional response assessments may not always apply in deciding when to either continue or stop treatment. While community physicians may increasingly focus more on duration of response, symptom relief, and how well patients tolerate treatment, there is a clear need for validated surrogate markers of biologic activity and response, as well as randomized trials that directly compare some of the targeted therapies being applied in advanced RCC.

  11. Effect of antisense oligonucleotides targeting telomerase catalytic subunit on tumor cell proliferationin vitro

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    To screen specific antitumor drugs targeting telomerase catalytic subunit (hEST2), 12 different hEST2 antisense oligonucleotides were designed based on hEST2 mRNA second structure and transfected into tumor cell lines by the lipofectin-mediated method. Cell growth activity was evaluated by MTT assay. hEST212 was picked out and its specificity, antitumor tree and continuous effect were analyzed. The results showed that hEST212 had promising antitumor activity in vitro, hEST2 can be used as a pratical target and an antisense drug candidate for cancer.

  12. A rapid and efficient method to express target genes in mammalian cells by baculovirus

    Institute of Scientific and Technical Information of China (English)

    Tong Cheng; Chen-Yu Xu; Ying-Bin Wang; Min Chen; Ting Wu; Jun Zhang; Ning-Shao Xia

    2004-01-01

    AIM: To investigate the modification of baculovirus vector and the feasibility of delivering exogenous genes into mammalian cells with the culture supernatant of Spodoptera frugiperta (Sf9) cells infected by recombinant baculoviruses.METHODS: Two recombinant baculoviruses (BacV-CMVEGFPA, BacV-CMV-EGFPB) containing CMV-EGFP expression cassette were constructed. HepG2 cells were directly incubated with the culture supernatant of Sf9 cells infected by recombinant baculoviruses, and reporter gene transfer and expression efficiencies were analyzed by flow cytometry (FCM). The optimal transduction conditions were investigated by FCM assay in HepG2 cells. Gene-transfer and expression efficiencies in HepG2 or CV1 cells by baculovirus vectors were compared with lipofectAMINE, recombinant retrovirus and vaccinia virus expression systems. Twenty different mammalian cell lines were used to investigate the feasibility of delivering exogenous genes into different mammalian cells with the culture supernatant of infected Sf9 cells.RESULTS: CMV promoter could directly express reporter genes in Sf9 cells with a relatively low efficiency. Target cells incubated with the 1:1 diluted culture supernatant (moi=50) for 12 h at 37 ℃ could achieve the highest transduction and expression efficiencies with least impairment to cell viability. Under similar conditions the baculovirus vector could achieve the highest gene-transfer and expression efficiency than lipofectAMINE, recombinant retrovirus and vaccinia virus expression systems. Most mammalian cell lines could be transduced with recombinant baculovirus. In primate adherent culture cells the recombinant baculovirus could arrive the highest infection and expression efficiencies, but it was not very satisfactory in the cell lines from mice and suspended culture cells.CONCLUSION: Mammalian cells incubated with the culture supernatant of infected Sf9 cells could serve as a very convenient way for rapid and efficient expression of foreign

  13. CD81, a cell cycle regulator, is a novel target for histone deacetylase inhibition in glioma cells.

    Science.gov (United States)

    Gensert, JoAnn M; Baranova, Oxana V; Weinstein, David E; Ratan, Rajiv R

    2007-06-01

    Recent advances in cancer cell biology have focused on histone deacetylase inhibitors (HDACi's) because they target pathways critical to the development and progression of disease. In particular, HDACi's can induce expression of epigenetically silenced genes that promote growth arrest, differentiation and cell death. In glioma cells, one such repressed gene is the tetraspanin CD81, which regulates cytostasis in various cell lines and in astrocytes, the major cellular component of gliomas. Our studies show that HDACi's, trichostatin and sodium butyrate, promote growth arrest and differentiation with negligible cell death in glioma cells and induce expression of CD81 and cyclin-dependent kinase inhibitor 1A (p21(CIP/WAF-1)), another regulator of cytostasis in astrocytes. Interference RNA knock-down of CD81 abrogates cytostasis promoted by HDAC inhibition indicating that HDACi-induced CD81 is responsible for growth arrest. Induction of CD81 expression through HDAC inhibition is a novel strategy to promote growth arrest in glioma cells.

  14. Molecular beacon-enabled purification of living cells by targeting cell type-specific mRNAs.

    Science.gov (United States)

    Wile, Brian M; Ban, Kiwon; Yoon, Young-Sup; Bao, Gang

    2014-10-01

    Molecular beacons (MBs) are dual-labeled oligonucleotides that fluoresce only in the presence of complementary mRNA. The use of MBs to target specific mRNAs allows sorting of specific cells from a mixed cell population. In contrast to existing approaches that are limited by available surface markers or selectable metabolic characteristics, the MB-based method enables the isolation of a wide variety of cells. For example, the ability to purify specific cell types derived from pluripotent stem cells (PSCs) is important for basic research and therapeutics. In addition to providing a general protocol for MB design, validation and nucleofection into cells, we describe how to isolate a specific cell population from differentiating PSCs. By using this protocol, we have successfully isolated cardiomyocytes differentiated from mouse or human PSCs (hPSCs) with ∼ 97% purity, as confirmed by electrophysiology and immunocytochemistry. After designing MBs, their ordering and validation requires 2 weeks, and the isolation process requires 3 h.

  15. Cell-type independent MYC target genes reveal a primordial signature involved in biomass accumulation.

    Directory of Open Access Journals (Sweden)

    Hongkai Ji

    Full Text Available The functions of key oncogenic transcription factors independent of context have not been fully delineated despite our richer understanding of the genetic alterations in human cancers. The MYC oncogene, which produces the Myc transcription factor, is frequently altered in human cancer and is a major regulatory hub for many cancers. In this regard, we sought to unravel the primordial signature of Myc function by using high-throughput genomic approaches to identify the cell-type independent core Myc target gene signature. Using a model of human B lymphoma cells bearing inducible MYC, we identified a stringent set of direct Myc target genes via chromatin immunoprecipitation (ChIP, global nuclear run-on assay, and changes in mRNA levels. We also identified direct Myc targets in human embryonic stem cells (ESCs. We further document that a Myc core signature (MCS set of target genes is shared in mouse and human ESCs as well as in four other human cancer cell types. Remarkably, the expression of the MCS correlates with MYC expression in a cell-type independent manner across 8,129 microarray samples, which include 312 cell and tissue types. Furthermore, the expression of the MCS is elevated in vivo in Eμ-Myc transgenic murine lymphoma cells as compared with premalignant or normal B lymphocytes. Expression of the MCS in human B cell lymphomas, acute leukemia, lung cancers or Ewing sarcomas has the highest correlation with MYC expression. Annotation of this gene signature reveals Myc's primordial function in RNA processing, ribosome biogenesis and biomass accumulation as its key roles in cancer and stem cells.

  16. Neurotensin, a novel target of Wnt/β-catenin pathway, promotes growth of neuroendocrine tumor cells.

    Science.gov (United States)

    Kim, Ji Tae; Liu, Chunming; Zaytseva, Yekaterina Y; Weiss, Heidi L; Townsend, Courtney M; Evers, B Mark

    2015-03-15

    Wnt/β-catenin signaling plays a pivotal role in regulating cell growth and differentiation by activation of the β-catenin/T-cell factor (TCF) complex and subsequent regulation of a set of target genes that have one or more TCF-binding elements (TBEs). Hyperactivation of this pathway has been implicated in numerous malignancies including human neuroendocrine tumors (NETs). Neurotensin (NT), an intestinal hormone, induces proliferation of several gastrointestinal (GI) cancers including cancers of the pancreas and colon. Here, we analyzed the human NT promoter in silico and found at least four consensus TBEs within the proximal promoter region. Using a combination of ChIP and luciferase reporter assays, we identified one TBE (located ∼900 bp proximal from the transcription start site) that was immunoprecipitated efficiently by TCF4-targeting antibody; mutation of this site attenuated the responsiveness to β-catenin. We also confirmed that the promoter activity and the mRNA and protein expression levels of NT were increased by various Wnt pathway activators and decreased by Wnt inhibitors in NET cell lines BON and QGP-1, which express and secrete NT. Similarly, the intracellular content and secretion of NT were induced by Wnt3a in these cells. Finally, inhibition of NT signaling suppressed cell proliferation and anchorage-independent growth and decreased expression levels of growth-related proteins in NET cells. Our results indicate that NT is a direct target of the Wnt/β-catenin pathway and may be a mediator for NET cell growth.

  17. Challenges and limitations of targeting cancer stem cells and/or the tumour microenvironment

    Directory of Open Access Journals (Sweden)

    Juan Sebastian Yakisich

    2012-05-01

    Full Text Available The existence of cancer cells with stem cell properties (Cancer Stem Cells, CSCs and their association with tumor resistance and relapse has led to the search for active compounds to eliminate these cells or modulate their stemness in the hope of curing cancer. So far, three classes of drugs that target cancer stemness (Stemness Modulator Drugs have been identified: i drugs that selectively eliminate CSCs (stem cell targeting drugs; ii drugs that decrease stemness (stemness inhibitor drugs; and iii drugs that promote stemness (stemness promoting drugs. In addition, microenvironment modulating drugs aimed at selectively targeting the stem cell niche are being investigated and may represent an important class of drug for cancer therapy. This article will briefly review the current use of these substances and discuss the potential outcomes, challenges and limitations of treatment modalities using these classes of drugs for cancer treatment. Finally, a modular tumor model will be proposed as a guide to integrate our knowledge on the biology of cancer stem cell with that of the tumor microenvironment to promote a more rational development of anticancer therapy.

  18. MiRNA-125a-5p inhibits glioblastoma cell proliferation and promotes cell differentiation by targeting TAZ

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Jian; Xiao, Gelei [Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); The Institute of Skull Base Surgery & Neuro-oncology at Hunan, Changsha, Hunan 410008 (China); Peng, Gang [Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); Liu, Dingyang [Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); The Institute of Skull Base Surgery & Neuro-oncology at Hunan, Changsha, Hunan 410008 (China); Wang, Zeyou [Cancer Research Institute, Central South University, Changsha, Hunan 410008 (China); Liao, Yiwei; Liu, Qing [Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); The Institute of Skull Base Surgery & Neuro-oncology at Hunan, Changsha, Hunan 410008 (China); Wu, Minghua [The Institute of Skull Base Surgery & Neuro-oncology at Hunan, Changsha, Hunan 410008 (China); Cancer Research Institute, Central South University, Changsha, Hunan 410008 (China); Yuan, Xianrui, E-mail: xry69@163.com [Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); The Institute of Skull Base Surgery & Neuro-oncology at Hunan, Changsha, Hunan 410008 (China)

    2015-02-06

    Highlights: • Expression of miR-125a-5p is inversely correlated with that of TAZ in glioma cells. • MiR-125a-5p represses TAZ expression in glioma cells. • MiR-125a-5p directly targets the 3′ UTR of TAZ mRNA and promotes its degradation. • MiR-125a-5p represses CTGF and survivin via TAZ, and inhibits glioma cell growth. • MiR-125a-5p inhibits the stem cell features of HFU-251 MG cells. - Abstract: Glioblastoma (GBM) is the most lethal brain tumor due to the resistance to conventional therapies, such as radiotherapy and chemotherapy. TAZ, an important mediator of the Hippo pathway, was found to be up-regulated in diverse cancers, including in GBM, and plays important roles in tumor initiation and progression. However, little is known about the regulation of TAZ expression in tumors. In this study, we found that miR-125a-5p is an important regulator of TAZ in glioma cells by directly targeting the TAZ 3′ UTR. MiR-125a-5p levels are inversely correlated with that of TAZ in normal astrocytes and a panel of glioma cell lines. MiR-125a-5p represses the expression of TAZ target genes, including CTGF and survivin, and inhibits cell proliferation and induces the differentiation of GBM cells; whereas over-expression of TAZ rescues the effects of miR-125a-5p. This study revealed a mechanism for TAZ deregulation in glioma cells, and also demonstrated a tumor suppressor role of miR-125a-5p in glioblastoma cells.

  19. Targeted Delivery of siRNA to Transferrin Receptor Overexpressing Tumor Cells via Peptide Modified Polyethylenimine

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    Yuran Xie

    2016-10-01

    Full Text Available The use of small interference RNA (siRNA to target oncogenes is a promising treatment approach for cancer. However, siRNA cancer therapies are hindered by poor delivery of siRNA to cancer cells. Transferrin receptor (TfR is overexpressed in many types of tumor cells and therefore is a potential target for the selective delivery of siRNA to cancer cells. Here, we used the TfR binding peptide HAIYPRH (HAI peptide conjugated to cationic polymer branched polyethylenimine (bPEI, optimized the coupling strategy, and the TfR selective delivery of siRNA was evaluated in cells with high (H1299 and low TfR expression (A549 and H460. The HAI-bPEI conjugate exhibited chemico-physical properties in terms of size, zeta-potential, and siRNA condensation efficiency similar to unmodified bPEI. Confocal microscopy and flow cytometry results revealed that HAI-bPEI selectively delivered siRNA to H1299 cells compared with A549 or H460 cells. Moreover, HAI-bPEI achieved more efficient glyceraldehyde 3-phosphate dehydrogenase (GAPDH gene knockdown in H1299 cells compared with bPEI alone. However, despite optimization of the targeting peptide and coupling strategy, HAI-bPEI can only silence reporter gene enhanced green fluorescent protein (eGFP at the protein level when chloroquine is present, indicating that further optimization of the conjugate is required. In conclusion, the HAI peptide may be useful to target TfR overexpressing tumors in targeted gene and siRNA delivery approaches.

  20. [In vitro targeting effect of lactoferrin modified PEGylated liposomes for hepatoma cells].

    Science.gov (United States)

    Wei, Min-yan; Zou, Qi; Wu, Chuan-bin; Xu, Yue-hong

    2015-10-01

    A lactoferrin-containing PEGylated liposome system (Lf-PLS) was developed and tested in vitro as a hepatoma-targeting drug delivery system. PEGylated liposomes (PLS) were successfully prepared using the thin film hydration method with peglipid post insertion. Lf was covalently conjugated onto the carboxyl terminal of DSPE-PEG2000-COOH on liposomes. Coumarin-6 was used to trace Lf-PLS with fluorescence. The cellular uptake of this system was carried out in asialoglycoprotein receptor (ASGPR) positive HepG2 cells via confocal microscopy and flow cytometry. The Lf-PLS liposome was observed as spherical or oval vesicles with the particle size around 130 nm, zeta potential about -30 mV and encapsulation efficiency more than 80%. The confocal microscopy images and flow cytometry data demonstrated that Lf-PLS resulted in significantly higher cell association by ASGPR positive HepG2 cells compared to PLS. The association between Lf-PLS and cells were dependent on the concentration, time and temperature, which was inhibited by pre-incubation with excessive free Lf. The results suggest that Lf-PLS has a good targeting effect on HepG2 cells in vitro. The targeting mechanism may be related to the specific binding of Lf and ASGPR on HepG2 cells, which guides Lf-PLS to the cell surface to induce an active endocytosis process. All these results demonstrated that Lf-PLS might be a potential drug delivery system in targeting hepatocellular carcinoma, which deserves more research on its targeting ability, antitumor efficiency, and metabolism in vivo for treatment of hepatomacellular carcinoma.

  1. Targeted metabolomics in cultured cells and tissues by mass spectrometry: method development and validation.

    Science.gov (United States)

    Abdel Rahman, Anas M; Pawling, Judy; Ryczko, Michael; Caudy, Amy A; Dennis, James W

    2014-10-03

    Metabolomics is the identification and quantitation of small bio-molecules (metabolites) in biological samples under various environmental and genetic conditions. Mass spectrometry provides the unique opportunity for targeted identification and quantification of known metabolites by selective reaction monitoring (SRM). However, reproducibility of this approach depends on careful consideration of sample preparation, chemical classes, and stability of metabolites to be evaluated. Herein, we introduce and validate a targeted metabolite profiling workflow for cultured cells and tissues by liquid chromatography-triple quadrupole tandem mass spectrometry. The method requires a one-step extraction of water-soluble metabolites and targeted analysis of central metabolites that include glycolysis, amino acids, nucleotides, citric acid cycle, and the hexosamine biosynthetic pathway. The sensitivity, reproducibility and molecular stability of each targeted metabolite were assessed under experimental conditions. Quantitation of metabolites by peak area ratio was linear with a dilution over a 4 fold dynamic range with minimal deviation R(2)=0.98. Inter- and intra-day precision with cells and tissues had an average coefficient of variation <15% for cultured cell lines, and somewhat higher for mouse liver tissues. The method applied in triplicate measurements readily distinguished immortalized cells from malignant cells, as well as mouse littermates based on their hepatic metabolic profiles.

  2. Regulation of mitochondrial morphology and cell cycle by microRNA-214 targeting Mitofusin2.

    Science.gov (United States)

    Bucha, Sudha; Mukhopadhyay, Debashis; Bhattacharyya, Nitai Pada

    2015-10-02

    Huntington's disease (HD) is an autosomal dominant neurodegenerative disease caused by the increase in CAG repeats beyond 36 at the exon1 of the gene Huntingtin (HTT). Among the various dysfunctions of biological processes in HD, transcription deregulation due to abnormalities in actions of transcription factors has been considered to be one of the important pathological conditions. In addition, deregulation of microRNA (miRNA) expression has been described in HD. Earlier, expression of microRNA-214 (miR-214) has been shown to increase in HD cell models and target HTT gene; the expression of the later being inversely correlated to that of miR-214. In the present communication, we observed that the expressions of several HTT co-expressed genes are modulated by exogenous expression of miR-214 or by its mutant. Among several HTT co-expressed genes, MFN2 was shown to be the direct target of miR-214. Exogenous expression of miR-214, repressed the expression of MFN2, increased the distribution of fragmented mitochondria and altered the distribution of cells in different phases of cell cycle. In summary, we have shown that increased expression of miR-214 observed in HD cell model could target MFN2, altered mitochondrial morphology and deregulated cell cycle. Inhibition of miR-214 could be a possible target of intervention in HD pathogenesis.

  3. Impact of genetic targets on therapy in head and neck squamous cell carcinoma.

    Science.gov (United States)

    Chaikhoutdinov, Irina; Goldenberg, David

    2013-01-01

    Despite advances in surgical technique, radiation therapy and chemotherapy, the mortality from head and neck squamous cell carcinoma (HNSCC) has not improved significantly. Squamous cell carcinoma is caused by tobacco use, alcohol consumption and infection with high-risk types of human papillomavirus. It is the 6th most common cancer in the world, with upwards of 45,000 new cases reported yearly in the United States alone.In recent years, there has been a significant increase in the understanding of the molecular and genetic pathogenesis of head and neck cancer, shedding light on the unexpected heterogeneity of the disease. Genetic analysis has led to new classification schemes for HNSCC, with different subgroups exhibiting different prognoses. In addition, multiple targets in aberrant signaling pathways have been identified using increasingly sophisticated bio-informatics tools. Advances in technology have allowed for novel delivery mechanisms to introduce genetic material into cells to produce a therapeutic effect by targeting cancer cells via a number of different approaches.A pressing need to develop novel therapies to augment current treatment modalities has led to a number of translational studies involving gene therapy in the treatment of HNSCC. This article will focus on a review of the most recent developments in molecular biology of head and neck squamous cell carcinoma in regards to possible targets for gene therapy, as well as the array of novel therapeutic strategies directed at these targets.

  4. siRNA targeting stathmin inhibits invasion and enhances chemotherapy sensitivity of stem cells derived from glioma cell lines.

    Science.gov (United States)

    Song, Yuwen; Mu, Luyan; Han, Xuezhe; Liu, Xiaoqian; Fu, Songbin

    2014-12-01

    Glioma is one of the most highly angiogenic tumors, and glioma stem cells (GSCs) are responsible for resistance to chemotherapy and radiotherapy, as well as recurrence after operation. Stathmin is substantial for mitosis and plays an important role in proliferation and migration of glioma-derived endothelial cells. However, the relationship between stathmin and GSCs is incompletely understood. Here we isolated GSCs from glioma cell lines U87MG and U251, and then used siRNA targeting stathmin for silencing. We showed that silencing of stathmin suppressed the proliferation, increased the apoptosis rate, and arrested the cell cycle at G2/M phase in GSCs. Silencing of stathmin in GSCs also resulted in inhibited the migration/invasion as well as the capability of vasculogenic mimicry. The susceptibility of GSCs to temozolomide was also enhanced by stathmin silencing. Our findings suggest stathmin as a potential target in GSCs for glioma treatment.

  5. HIV-1-Induced Small T Cell Syncytia Can Transfer Virus Particles to Target Cells through Transient Contacts

    Directory of Open Access Journals (Sweden)

    Menelaos Symeonides

    2015-12-01

    Full Text Available HIV-1 Env mediates fusion of viral and target cell membranes, but it can also mediate fusion of infected (producer and target cells, thus triggering the formation of multinucleated cells, so-called syncytia. Large, round, immobile syncytia are readily observable in cultures of HIV-1-infected T cells, but these fast growing “fusion sinks” are largely regarded as cell culture artifacts. In contrast, small HIV-1-induced syncytia were seen in the paracortex of peripheral lymph nodes and other secondary lymphoid tissue of HIV-1-positive individuals. Further, recent intravital imaging of lymph nodes in humanized mice early after their infection with HIV-1 demonstrated that a significant fraction of infected cells were highly mobile, small syncytia, suggesting that these entities contribute to virus dissemination. Here, we report that the formation of small, migratory syncytia, for which we provide further quantification in humanized mice, can be recapitulated in vitro if HIV-1-infected T cells are placed into 3D extracellular matrix (ECM hydrogels rather than being kept in traditional suspension culture systems. Intriguingly, live-cell imaging in hydrogels revealed that these syncytia, similar to individual infected cells, can transiently interact with uninfected cells, leading to rapid virus transfer without cell-cell fusion. Infected cells were also observed to deposit large amounts of viral particles into the extracellular space. Altogether, these observations suggest the need to further evaluate the biological significance of small, T cell-based syncytia and to consider the possibility that these entities do indeed contribute to virus spread and pathogenesis.

  6. Targeting of follicle stimulating hormone peptide-conjugated dendrimers to ovarian cancer cells

    Science.gov (United States)

    Modi, Dimple A.; Sunoqrot, Suhair; Bugno, Jason; Lantvit, Daniel D.; Hong, Seungpyo; Burdette, Joanna E.

    2014-02-01

    Ovarian cancer is the most lethal gynecological malignancy. Current treatment modalities include a combination of surgery and chemotherapy, which often lead to loss of fertility in premenopausal women and a myriad of systemic side effects. To address these issues, we have designed poly(amidoamine) (PAMAM) dendrimers to selectively target the follicle stimulating hormone receptor (FSHR), which is overexpressed by tumorigenic ovarian cancer cells but not by immature primordial follicles and other non-tumorigenic cells. Fluorescein-labeled generation 5 (G5) PAMAM dendrimers were conjugated with the binding peptide domain of FSH (FSH33) that has a high affinity to FSHR. The targeted dendrimers exhibited high receptor selectivity to FSHR-expressing OVCAR-3 cells, resulting in significant uptake and downregulation of an anti-apoptotic protein survivin, while showing minimal interactions with SKOV-3 cells that do not express FSHR. The selectivity of the FSH33-targeted dendrimers was further validated in 3D organ cultures of normal mouse ovaries. Immunostaining of the conjugates revealed their selective binding and uptake by ovarian surface epithelium (OSE) cells that express FSHR, while sparing the immature primordial follicles. In addition, an in vivo study monitoring tissue accumulation following a single intraperitoneal (i.p.) injection of the conjugates showed significantly higher accumulation of FSH33-targeted dendrimers in the ovary and oviduct compared to the non-targeted conjugates. These proof-of-concept findings highlight the potential of these FSH33-targeted dendrimers to serve as a delivery platform for anti-ovarian cancer drugs, while reducing their systemic side effects by preventing nonspecific uptake by the primordial follicles.Ovarian cancer is the most lethal gynecological malignancy. Current treatment modalities include a combination of surgery and chemotherapy, which often lead to loss of fertility in premenopausal women and a myriad of systemic side

  7. Notch signaling: targeting cancer stem cells and epithelial-to-mesenchymal transition

    Directory of Open Access Journals (Sweden)

    Espinoza I

    2013-09-01

    Full Text Available Ingrid Espinoza,1,2 Radhika Pochampally,1,2 Fei Xing,1 Kounosuke Watabe,1,3 Lucio Miele1,4 1Cancer Institute, 2Department of Biochemistry, 3Department of Microbiology, 4Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, USA Abstract: Notch signaling is an evolutionarily conserved pathway involved in cell fate control during development, stem cell self-renewal, and postnatal tissue differentiation. Roles for Notch in carcinogenesis, the biology of cancer stem cells, tumor angiogenesis, and epithelial-to-mesenchymal transition (EMT have been reported. This review describes the role of Notch in the “stemness” program in cancer cells and in metastases, together with a brief update on the Notch inhibitors currently under investigation in oncology. These agents may be useful in targeting cancer stem cells and to reverse the EMT process. Keywords: Notch signaling, EMT, cancer stem cells, mesenchymal stem cells, metastases, Notch inhibitors

  8. Targeted liposome-loaded microbubbles for cell-specific ultrasound-triggered drug delivery.

    Science.gov (United States)

    Geers, Bart; De Wever, Olivier; Demeester, Joseph; Bracke, Marc; De Smedt, Stefaan C; Lentacker, Ine

    2013-12-01

    One of the main problems in cancer treatment is disease relapse through metastatic colonization, which is caused by circulating tumor cells (CTCs). This work reports on liposome-loaded microbubbles targeted to N-cadherin, a cell-cell adhesion molecule expressed by CTCs. It is shown that such microbubbles can indeed bind to N-cadherin at the surface of HMB2 cells. Interestingly, in a mixture of cells with and without N-cadherin expression, binding of the liposome-loaded microbubbles mainly occurs to the N-cadherin-expressing cells. Importantly, applying ultrasound results in the intracellular delivery of a model drug (loaded in the liposomes) in the N-cadherin-expressing cells only. As described in this paper, such liposome-loaded microbubbles may find application as theranostics and in devices aimed for the specific killing of CTCs in blood.

  9. Targeted immunotherapy of cancer with CAR T cells: achievements and challenges.

    Science.gov (United States)

    Lipowska-Bhalla, Grazyna; Gilham, David E; Hawkins, Robert E; Rothwell, Dominic G

    2012-07-01

    The adoptive transfer of chimeric antigen receptor (CAR)-expressing T cells is a relatively new but promising approach in the field of cancer immunotherapy. This therapeutic strategy is based on the genetic reprogramming of T cells with an artificial immune receptor that redirects them against targets on malignant cells and enables their destruction by exerting T cell effector functions. There has been an explosion of interest in the use of CAR T cells as an immunotherapy for cancer. In the pre-clinical setting, there has been a considerable focus upon optimizing the structural and signaling potency of the CAR while advances in bio-processing technology now mean that the clinical testing of these gene-modified T cells has become a reality. This review will summarize the concept of CAR-based immunotherapy and recent clinical trial activity and will further discuss some of the likely future challenges facing CAR-modified T cell therapies.

  10. Generation of CRISPR/Cas9-mediated gene-targeted pigs via somatic cell nuclear transfer.

    Science.gov (United States)

    Zhou, Xiaoqing; Xin, Jige; Fan, Nana; Zou, Qingjian; Huang, Jiao; Ouyang, Zhen; Zhao, Yu; Zhao, Bentian; Liu, Zhaoming; Lai, Sisi; Yi, Xiaoling; Guo, Lin; Esteban, Miguel A; Zeng, Yangzhi; Yang, Huaqiang; Lai, Liangxue

    2015-03-01

    The domestic pig has been widely used as an important large animal model. Precise and efficient genetic modification in pig provides a great promise in biomedical research. Recently, clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas) system has been successfully used to produce many gene-targeted animals. However, these animals have been generated by co-injection of Cas9 mRNA and single-guide RNA (sgRNA) into one-cell stage embryos, which mostly resulted in mosaicism of the modification. One or two rounds of further breeding should be performed to obtain homozygotes with identical genotype and phenotype. To address this issue, gene-targeted somatic cells can be used as donor for somatic cell nuclear transfer (SCNT) to produce gene-targeted animals with single and identical mutations. In this study, we applied Cas9/sgRNAs to effectively direct gene editing in porcine fetal fibroblasts and then mutant cell colonies were used as donor to generate homozygous gene-targeted pigs through single round of SCNT. As a result, we successfully obtained 15 tyrosinase (TYR) biallelic mutant pigs and 20 PARK2 and PINK1 double-gene knockout (KO) pigs. They were all homozygous and no off-target mutagenesis was detected by comprehensive analysis. TYR (-/-) pigs showed typical albinism and the expression of parkin and PINK1 were depleted in PARK2 (-/-)/PINK1 (-/-) pigs. The results demonstrated that single- or double-gene targeted pigs can be effectively achieved by using the CRISPR/Cas9 system combined with SCNT without mosaic mutation and detectable off-target effects. This gene-editing system provides an efficient, rapid, and less costly manner to generate genetically modified pigs or other large animals.

  11. Prolactin-induced Subcellular Targeting of GLUT1 Glucose Transporter in Living Mammary Epithelial Cells

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    Arieh Riskin

    2015-10-01

    Full Text Available Background: Studying the biological pathways involved in mammalian milk production during lactation could have many clinical implications. The mammary gland is unique in its requirement for transport of free glucose into the cell for the synthesis of lactose, the primary carbohydrate in milk. Objective: To study GLUT1 trafficking and subcellular targeting in living mammary epithelial cells (MEC in culture. Methods: Immunocytochemistry was used to study GLUT1 hormonally regulated subcellular targeting in human MEC (HMEC. To study GLUT1 targeting and recycling in living mouse MEC (MMEC in culture, we constructed fusion proteins of GLUT1 and green fluorescent protein (GFP and expressed them in CIT3 MMEC. Cells were maintained in growth medium (GM, or exposed to secretion medium (SM, containing prolactin. Results: GLUT1 in HMEC localized primarily to the plasma membrane in GM. After exposure to prolactin for 4 days, GLUT1 was targeted intracellularly and demonstrated a perinuclear distribution, co-localizing with lactose synthetase. The dynamic trafficking of GFP-GLUT1 fusion proteins in CIT3 MMEC suggested a basal constitutive GLUT1 recycling pathway between an intracellular pool and the cell surface that targets most GLUT1 to the plasma membrane in GM. Upon exposure to prolactin in SM, GLUT1 was specifically targeted intracellularly within 90–110 minutes. Conclusions: Our studies suggest intracellular targeting of GLUT1 to the central vesicular transport system upon exposure to prolactin. The existence of a dynamic prolactin-induced sorting machinery for GLUT1 could be important for transport of free glucose into the Golgi for lactose synthesis during lactation.

  12. CRACC-targeting Fc-fusion protein induces activation of NK cells and DCs and improves T cell immune responses to antigenic targets.

    Science.gov (United States)

    Aldhamen, Yasser A; Rastall, David P W; Chen, Weimin; Seregin, Sergey S; Pereira-Hicks, Cristiane; Godbehere, Sarah; Kaminski, Norbert E; Amalfitano, Andrea

    2016-06-08

    The CD2-like receptor activating cytotoxic cell (CRACC) receptor is a member of the SLAM family of receptors that are found on several types of immune cells. We previously demonstrated that increasing the abundance of the adaptor protein EAT-2 during vaccination enhanced innate and adaptive immune responses to vaccine antigens. Engagement of the CRACC receptor in the presence of the EAT-2 adaptor generally results in immune cell activation, while activating CRACC signaling in cells that lack EAT-2 adaptor inhibits their effector and regulatory functions. As EAT-2 is the only SAP adaptor that interacts with the CRACC receptor, we hypothesized that technologies that specifically modulate CRACC signaling during vaccination may also improve antigen specific adaptive immune responses. To test this hypothesis, we constructed a CRACC-targeting Fc fusion protein and included it in vaccination attempts. Indeed, mice co-vaccinated with the CRACC-Fc fusion protein and an adenovirus vaccine expressing the HIV-Gag protein had improved Gag-specific T cell responses, as compared to control mice. These responses are characterized by increased numbers of Gag-specific tetramer+ CD8+ T cells and increases in production of IFNγ, TNFα, and IL2, by Gag-specific CD8+ T cells. Moreover, our results revealed that use of the CRACC-Fc fusion protein enhances vaccine-elicited innate immune responses, as characterized by increased dendritic cells (DCs) maturation and IFNγ production from NK cells. This study highlights the importance of CRACC signaling during the induction of an immune response generally, and during vaccinations specifically, and also lends insight into the mechanisms underlying our prior results noting EAT-2-dependent improvements in vaccine efficacy.

  13. Combinational targeting offsets antigen escape and enhances effector functions of adoptively transferred T cells in glioblastoma.

    Science.gov (United States)

    Hegde, Meenakshi; Corder, Amanda; Chow, Kevin K H; Mukherjee, Malini; Ashoori, Aidin; Kew, Yvonne; Zhang, Yi Jonathan; Baskin, David S; Merchant, Fatima A; Brawley, Vita S; Byrd, Tiara T; Krebs, Simone; Wu, Meng Fen; Liu, Hao; Heslop, Helen E; Gottschalk, Stephen; Gottachalk, Stephen; Yvon, Eric; Ahmed, Nabil

    2013-11-01

    Preclinical and early clinical studies have demonstrated that chimeric antigen receptor (CAR)-redirected T cells are highly promising in cancer therapy. We observed that targeting HER2 in a glioblastoma (GBM) cell line results in the emergence of HER2-null tumor cells that maintain the expression of nontargeted tumor-associated antigens. Combinational targeting of these tumor-associated antigens could therefore offset this escape mechanism. We studied the single-cell coexpression patterns of HER2, IL-13Rα2, and EphA2 in primary GBM samples using multicolor flow cytometry and immunofluorescence, and applied a binomial routine to the permutations of antigen expression and the related odds of complete tumor elimination. This mathematical model demonstrated that cotargeting HER2 and IL-13Rα2 could maximally expand the therapeutic reach of the T cell product in all primary tumors studied. Targeting a third antigen did not predict an added advantage in the tumor cohort studied. We therefore generated bispecific T cell products from healthy donors and from GBM patients by pooling T cells individually expressing HER2 and IL-13Rα2-specific CARs and by making individual T cells to coexpress both molecules. Both HER2/IL-13Rα2-bispecific T cell products offset antigen escape, producing enhanced effector activity in vitro immunoassays (against autologous glioma cells in the case of GBM patient products) and in an orthotopic xenogeneic murine model. Further, T cells coexpressing HER2 and IL-13Rα2-CARs exhibited accentuated yet antigen-dependent downstream signaling and a particularly enhanced antitumor activity.

  14. GEM-loaded magnetic albumin nanospheres modified with cetuximab for simultaneous targeting, magnetic resonance imaging, and double-targeted thermochemotherapy of pancreatic cancer cells

    Directory of Open Access Journals (Sweden)

    Wang L

    2015-03-01

    Full Text Available Ling Wang,1 Yanli An,2 Chenyan Yuan,3 Hao Zhang,2 Chen Liang,2 Fengan Ding,2 Qi Gao,1 Dongsheng Zhang4 1Department of Ultrasonography, Zhong Da Hospital, Medical School, Southeast University, Nanjing, People’s Republic of China; 2Medical School, Southeast University, Nanjing, People’s Republic of China; 3Department of Clinical Laboratory, Zhong Da Hospital, Medical School, Southeast University, Nanjing, People’s Republic of China; 4Jiangsu Key Laboratory for Biomaterials and Devices, Medical School, Southeast University, Nanjing, People’s Republic of China Background: Targeted delivery is a promising strategy to improve the diagnostic imaging and therapeutic effect of cancers. In this paper, novel cetuximab (C225-conjugated, gemcitabine (GEM-containing magnetic albumin nanospheres (C225-GEM/MANs were fabricated and applied as a theranostic nanocarrier to conduct simultaneous targeting, magnetic resonance imaging (MRI, and double-targeted thermochemotherapy against pancreatic cancer cells. Methods: Fe3O4 nanoparticles (NPs and GEM co-loaded albumin nanospheres (GEM/MANs were prepared, and then C225 was further conjugated to synthesize C225-GEM/MANs. Their morphology, mean particle size, GEM encapsulation ratio, specific cell-binding ability, and thermal dynamic profiles were characterized. The effects of discriminating different EGFR-expressing pancreatic cancer cells (AsPC-1 and MIA PaCa-2 and monitoring cellular targeting effects were assessed by targeted MRI. Lastly, the antitumor efficiency of double/C225/magnetic-targeted and nontargeted thermochemotherapy was compared with chemotherapy alone using 3-(4, 5-dimethyl-2-thiazolyl-2,5-diphenyl-2H-tetrazolium bromide (MTT and flow cytometry (FCM assay. Results: When treated with targeted nanospheres, AsPC-1 cells showed a significantly less intense MRI T2 signal than MIA PaCa-2 cells, while both cells had similar signal strength when incubated with nontargeted nanospheres. T2 signal

  15. Cell-based proteome profiling of potential dasatinib targets by use of affinity-based probes.

    Science.gov (United States)

    Shi, Haibin; Zhang, Chong-Jing; Chen, Grace Y J; Yao, Shao Q

    2012-02-15

    Protein kinases (PKs) play an important role in the development and progression of cancer by regulating cell growth, survival, invasion, metastasis, and angiogenesis. Dasatinib (BMS-354825), a dual Src/Abl inhibitor, is a promising therapeutic agent with oral bioavailability. It has been used for the treatment of imatinib-resistant chronic myelogenous leukemia (CML). Most kinase inhibitors, including Dasatinib, inhibit multiple cellular targets and do not possess exquisite cellular specificity. Recent efforts in kinase research thus focus on the development of large-scale, proteome-wide chemical profiling methods capable of rapid identification of potential cellular (on- and off-) targets of kinase inhibitors. Most existing approaches, however, are still problematic and in many cases not compatible with live-cell studies. In this work, we have successfully developed a cell-permeable kinase probe (DA-2) capable of proteome-wide profiling of potential cellular targets of Dasatinib. In this way, highly regulated, compartmentalized kinase-drug interactions were maintained. By comparing results obtained from different proteomic setups (live cells, cell lysates, and immobilized affinity matrix), we found DA-2 was able to identify significantly more putative kinase targets. In addition to Abl and Src family tyrosine kinases, a number of previously unknown Dasatinib targets have been identified, including several serine/threonine kinases (PCTK3, STK25, eIF-2A, PIM-3, PKA C-α, and PKN2). They were further validated by pull-down/immunoblotting experiments as well as kinase inhibition assays. Further studies are needed to better understand the exact relevance of Dasatinib and its pharmacological effects in relation to these newly identified cellular targets. The approach developed herein should be amenable to the study of many of the existing reversible drugs/drug candidates.

  16. Inhibition of human esophageal squamous cell carcinomas by targeted silencing of tumor enhancer genes: an overview.

    Science.gov (United States)

    Islamian, Jalil Pirayesh; Mohammadi, Mohsen; Baradaran, Behzad

    2014-06-01

    Esophageal cancer has been reported as the ninth most common malignancy and ranks as the sixth most frequent cause of death worldwide. Esophageal cancer treatment involves surgery, chemotherapy, radiation therapy, or combination therapy. Novel strategies are needed to boost the oncologic outcome. Recent advances in the molecular biology of esophageal cancer have documented the role of genetic alterations in tumorigenesis. Oncogenes serve a pivotal function in tumorigenesis. Targeted therapies are directed at the unique molecular signature of cancer cells for enhanced efficacy with low toxicity. RNA interference (RNAi) technology is a powerful tool for silencing endogenous or exogenous genes in mammalian cells. Related results have shown that targeting oncogenes with siRNAs, specifically the mRNA, effectively reduces tumor cell proliferation and induces apoptotic cell death. This article will briefly review studies on silencing tumor enhancer genes related to the induction of esophageal cancer.

  17. Eosinophils and mast cells as therapeutic targets in pediatric functional dyspepsia

    Institute of Scientific and Technical Information of China (English)

    Craig; A; Friesen; Jennifer; V; Schurman; Jennifer; M; Colombo; Susan; M; Abdel-Rahman

    2013-01-01

    There is an increasing appreciation for the importance of inflammation as a pathophysiologic entity that contributes to functional gastrointestinal disorders including functional dyspepsia(FD).Importantly,inflammation may serve as a mediator between psychologic and physiologic functions.This manuscript reviews the literature implicating two inflammatory cell types,mast cells and eosinophils,in the generation of dyspeptic symptoms and explores their potential as targets for the treatment of FD.There are a number of inciting events which may initiate an inflammatory response,and the subsequent recruitment and activation of mast cells and eosinophils.These include internal triggers such as stress and anxiety,as well as external triggers such as microbes and allergens.Previous studies suggest that there may be efficacy in utilizing medications directed at mast cells and eosinophils.Evidence exists to suggest that combining "anti-inflammatory" medications with other treatments targeting stress can improve the rate of symptom resolution in pediatric FD.

  18. Direct activation of the apoptosis machinery as a mechanism to target cancer cells.

    Science.gov (United States)

    Nguyen, Jack T; Wells, James A

    2003-06-24

    Apoptosis plays a pivotal role in the cytotoxic activity of most chemotherapeutic drugs, and defects in this pathway provide a basis for drug resistance in many cancers. Thus the ability to restore apoptosis by using small molecules could have important therapeutic implications. Using a cell-free assay to simultaneously target multiple components of the apoptosis pathway, we identified a class of compounds that activate caspases in a cytochrome c-dependent manner and induce apoptosis in whole cells. By reconstituting the apoptosis pathway with purified proteins, we determined that these compounds promote the protein-protein association of Apaf-1 into the functional apoptosome. These compounds exert cytostatic and cytotoxic effects on a variety of cancer cell lines while having little or no activity against the normal cell lines tested. These findings suggest that direct activation of the basic apoptosis machinery may be a viable mechanism to selectively target cancer.

  19. Antiproliferative Activity of Crocin Involves Targeting of Microtubules in Breast Cancer Cells

    Science.gov (United States)

    Hire, Rupali R.; Srivastava, Shalini; Davis, Melissa B.; Kumar Konreddy, Ananda; Panda, Dulal

    2017-01-01

    Crocin, a component of saffron spice, is known to have an anticancer activity. However, the targets of crocin are not known. In this study, crocin was found to inhibit the proliferation of HCC70, HCC1806, HeLa and CCD1059sk cells by targeting microtubules. Crocin depolymerized both the interphase and mitotic microtubules of different cancer cells, inhibited mitosis and induced multipolar spindle formation in these cells. In vitro, crocin inhibited the assembly of pure tubulin as well as the assembly of microtubule-associated protein rich tubulin. Electron microscopic analysis showed that crocin inhibited microtubule assembly while it induced aggregation of tubulin at higher concentrations. Crocin co-eluted with tubulin suggesting that it binds to tubulin. Vinblastine inhibited the binding of crocin to tubulin while podophyllotoxin did not inhibit the crocin binding indicating that crocin binds at the vinblastine site on tubulin. The results suggested that crocin inhibited cell proliferation mainly by disrupting the microtubule network. PMID:28337976

  20. EphrinA1-targeted nanoshells for photothermal ablation of prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Andre M Gobin

    2008-10-01

    Full Text Available Andre M Gobin, James J Moon, Jennifer L WestDepartment of Bioengineering, Rice University, Houston, TX, USAAbstract: Gold-coated silica nanoshells are a class of nanoparticles that can be designed to possess strong absorption of light in the near infrared (NIR wavelength region. When injected intravenously, these nanoshells have been shown to accumulate in tumors and subsequently mediate photothermal treatment, leading to tumor regression. In this work, we sought to improve their specificity by targeting them to prostate tumor cells. We report selective targeting of PC-3 cells with nanoshells conjugated to ephrinA1, a ligand for EphA2 receptor that is overexpressed on PC-3 cells. We demonstrate selective photo-thermal destruction of these cells upon application of the NIR laser.Keywords: nanoshell, near infrared, photothermal treatment, prostate cancer

  1. Genomic targets of Brachyury (T in differentiating mouse embryonic stem cells.

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    Amanda L Evans

    Full Text Available The T-box transcription factor Brachyury (T is essential for formation of the posterior mesoderm and the notochord in vertebrate embryos. Work in the frog and the zebrafish has identified some direct genomic targets of Brachyury, but little is known about Brachyury targets in the mouse.Here we use chromatin immunoprecipitation and mouse promoter microarrays to identify targets of Brachyury in embryoid bodies formed from differentiating mouse ES cells. The targets we identify are enriched for sequence-specific DNA binding proteins and include components of signal transduction pathways that direct cell fate in the primitive streak and tailbud of the early embryo. Expression of some of these targets, such as Axin2, Fgf8 and Wnt3a, is down regulated in Brachyury mutant embryos and we demonstrate that they are also Brachyury targets in the human. Surprisingly, we do not observe enrichment of the canonical T-domain DNA binding sequence 5'-TCACACCT-3' in the vicinity of most Brachyury target genes. Rather, we have identified an (AC(n repeat sequence, which is conserved in the rat but not in human, zebrafish or Xenopus. We do not understand the significance of this sequence, but speculate that it enhances transcription factor binding in the regulatory regions of Brachyury target genes in rodents.Our work identifies the genomic targets of a key regulator of mesoderm formation in the early mouse embryo, thereby providing insights into the Brachyury-driven genetic regulatory network and allowing us to compare the function of Brachyury in different species.

  2. Quantification of Mesenchymal Stem Cell (MSC delivery to a target site using in vivo confocal microscopy.

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    Luke J Mortensen

    Full Text Available The ability to deliver cells to appropriate target tissues is a prerequisite for successful cell-based therapy. To optimize cell therapy it is therefore necessary to develop a robust method of in vivo cell delivery quantification. Here we examine Mesenchymal Stem Cells (MSCs labeled with a series of 4 membrane dyes from which we select the optimal dye combination for pair-wise comparisons of delivery to inflamed tissue in the mouse ear using confocal fluorescence imaging. The use of an optimized dye pair for simultaneous tracking of two cell populations in the same animal enables quantification of a test population that is referenced to an internal control population, thereby eliminating intra-subject variations and variations in injected cell numbers. Consistent results were obtained even when the administered cell number varied by more than an order of magnitude, demonstrating an ability to neutralize one of the largest sources of in vivo experimental error and to greatly reduce the number of cells required to evaluate cell delivery. With this method, we are able to show a small but significant increase in the delivery of cytokine pre-treated MSCs (TNF-α & IFN-γ compared to control MSCs. Our results suggest future directions for screening cell strategies using our in vivo cell delivery assay, which may be useful to develop methods to maximize cell therapeutic potential.

  3. Protein characterization of intracellular target-sorted, formalin-fixed cell subpopulations

    Science.gov (United States)

    Sadick, Jessica S.; Boutin, Molly E.; Hoffman-Kim, Diane; Darling, Eric M.

    2016-01-01

    Cellular heterogeneity is inherent in most human tissues, making the investigation of specific cell types challenging. Here, we describe a novel, fixation/intracellular target-based sorting and protein extraction method to provide accurate protein characterization for cell subpopulations. Validation and feasibility tests were conducted using homogeneous, neural cell lines and heterogeneous, rat brain cells, respectively. Intracellular proteins of interest were labeled with fluorescent antibodies for fluorescence-activated cell sorting. Reproducible protein extraction from fresh and fixed samples required lysis buffer with high concentrations of Tris-HCl and sodium dodecyl sulfate as well as exposure to high heat. No deterioration in protein amount or quality was observed for fixed, sorted samples. For the feasibility experiment, a primary rat subpopulation of neuronal cells was selected for based on high, intracellular β-III tubulin signal. These cells showed distinct protein expression differences from the unsorted population for specific (phosphorylated tau) and non-specific (total tau) protein targets. Our approach allows for determining more accurate protein profiles directly from cell types of interest and provides a platform technology in which any cell subpopulation can be biochemically investigated. PMID:27666089

  4. Evodiamine selectively targets cancer stem-like cells through the p53-p21-Rb pathway.

    Science.gov (United States)

    Han, Seula; Woo, Jong Kyu; Jung, Yuchae; Jeong, Dawoon; Kang, Minsook; Yoo, Young-Ji; Lee, Hani; Oh, Seung Hyun; Ryu, Jae-Ha; Kim, Woo-Young

    2016-01-22

    In spite of the recent improvements, the resistance to chemotherapy/radiotherapy followed by relapse is the main hurdle for the successful treatment of breast cancer, a leading cause of death in women. A small population of breast cancer cells that have stem-like characteristics (cancer stem-like cells; CSLC) may contribute to this resistance and relapse. Here, we report on a component of a traditional Chinese medicine, evodiamine, which selectively targets CSLC of breast cancer cell lines MCF7 and MDAMB 231 at a concentration that does show a little or no cytotoxic effect on bulk cancer cells. While evodiamine caused the accumulation of bulk cancer cells at the G2/M phase, it did not hold CSLC in a specific cell cycle phase but instead, selectively killed CSLC. This was not due to the culture of CSLC in suspension or without FBS. A proteomic analysis and western blotting revealed that evodiamine changed the expression of cell cycle regulating molecules more efficiently in CSLC cells than in bulk cancer cells. Surprisingly, evodiamine selectively activated p53 and p21 and decreased inactive Rb, the master molecules in G1/S checkpoint. These data collectively suggest a novel mechanism involving CSLC-specific targeting by evodiamine and its possible use to the therapy of breast cancer.

  5. Clinical regressions and broad immune activation following combination therapy targeting human NKT cells in myeloma.

    Science.gov (United States)

    Richter, Joshua; Neparidze, Natalia; Zhang, Lin; Nair, Shiny; Monesmith, Tamara; Sundaram, Ranjini; Miesowicz, Fred; Dhodapkar, Kavita M; Dhodapkar, Madhav V

    2013-01-17

    Natural killer T (iNKT) cells can help mediate immune surveillance against tumors in mice. Prior studies targeting human iNKT cells were limited to therapy of advanced cancer and led to only modest activation of innate immunity. Clinical myeloma is preceded by an asymptomatic precursor phase. Lenalidomide was shown to mediate antigen-specific costimulation of human iNKT cells. We treated 6 patients with asymptomatic myeloma with 3 cycles of combination of α-galactosylceramide-loaded monocyte-derived dendritic cells and low-dose lenalidomide. Therapy was well tolerated and led to reduction in tumor-associated monoclonal immunoglobulin in 3 of 4 patients with measurable disease. Combination therapy led to activation-induced decline in measurable iNKT cells and activation of NK cells with an increase in NKG2D and CD56 expression. Treatment also led to activation of monocytes with an increase in CD16 expression. Each cycle of therapy was associated with induction of eosinophilia as well as an increase in serum soluble IL2 receptor. Clinical responses correlated with pre-existing or treatment-induced antitumor T-cell immunity. These data demonstrate synergistic activation of several innate immune cells by this combination and the capacity to mediate tumor regression. Combination therapies targeting iNKT cells may be of benefit toward prevention of cancer in humans.

  6. Myo/Nog cells: targets for preventing the accumulation of skeletal muscle-like cells in the human lens.

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    Jacquelyn Gerhart

    Full Text Available Posterior capsule opacification (PCO is a vision impairing condition that arises in some patients following cataract surgery. The fibrotic form of PCO is caused by myofibroblasts that may emerge in the lens years after surgery. In the chick embryo lens, myofibroblasts are derived from Myo/Nog cells that are identified by their expression of the skeletal muscle specific transcription factor MyoD, the bone morphogenetic protein inhibitor Noggin, and the epitope recognized by the G8 monoclonal antibody. The goal of this study was to test the hypothesis that depletion of Myo/Nog cells will prevent the accumulation of myofibroblasts in human lens tissue. Myo/Nog cells were present in anterior, equatorial and bow regions of the human lens, cornea and ciliary processes. In anterior lens tissue removed by capsulorhexis, Myo/Nog cells had synthesized myofibroblast and skeletal muscle proteins, including vimentin, MyoD and sarcomeric myosin. Alpha smooth muscle actin (α-SMA was detected in a subpopulation of Myo/Nog cells. Areas of the capsule denuded of epithelial cells were surrounded by Myo/Nog cells. Some of these cell free areas contained a wrinkle in the capsule. Depletion of Myo/Nog cells eliminated cells expressing skeletal muscle proteins in 5-day cultures but did not affect cells immunoreactive for beaded filament proteins that accumulate in differentiating lens epithelial cells. Transforming growth factor-betas 1 and 2 that mediate an epithelial-mesenchymal transition, did not induce the expression of skeletal muscle proteins in lens cells following Myo/Nog cell depletion. This study demonstrates that Myo/Nog cells in anterior lens tissue removed from cataract patients have undergone a partial differentiation to skeletal muscle. Myo/Nog cells appear to be the source of skeletal muscle-like cells in explants of human lens tissue. Targeting Myo/Nog cells with the G8 antibody during cataract surgery may reduce the incidence of PCO.

  7. Early T Cell Recognition of B Cells following Epstein-Barr Virus Infection: Identifying Potential Targets for Prophylactic Vaccination.

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    Jill M Brooks

    2016-04-01

    Full Text Available Epstein-Barr virus, a B-lymphotropic herpesvirus, is the cause of infectious mononucleosis, has strong aetiologic links with several malignancies and has been implicated in certain autoimmune diseases. Efforts to develop a prophylactic vaccine to prevent or reduce EBV-associated disease have, to date, focused on the induction of neutralising antibody responses. However, such vaccines might be further improved by inducing T cell responses capable of recognising and killing recently-infected B cells. In that context, EBNA2, EBNA-LP and BHRF1 are the first viral antigens expressed during the initial stage of B cell growth transformation, yet have been poorly characterised as CD8+ T cell targets. Here we describe CD8+ T cell responses against each of these three "first wave" proteins, identifying target epitopes and HLA restricting alleles. While EBNA-LP and BHRF1 each contained one strong CD8 epitope, epitopes within EBNA2 induced immunodominant responses through several less common HLA class I alleles (e.g. B*3801 and B*5501, as well as subdominant responses through common class I alleles (e.g. B7 and C*0304. Importantly, such EBNA2-specific CD8+ T cells recognised B cells within the first day post-infection, prior to CD8+ T cells against well-characterised latent target antigens such as EBNA3B or LMP2, and effectively inhibited outgrowth of EBV-transformed B cell lines. We infer that "first wave" antigens of the growth-transforming infection, especially EBNA2, constitute potential CD8+ T cell immunogens for inclusion in prophylactic EBV vaccine design.

  8. Targeting stemness is an effective strategy to control EML4-ALK+ non-small cell lung cancer cells.

    Science.gov (United States)

    Oh, Se Jin; Noh, Kyung Hee; Lee, Young-Ho; Hong, Soon-Oh; Song, Kwon-Ho; Lee, Hyo-Jung; Kim, Soyeon; Kim, Tae Min; Jeon, Ju-Hong; Seo, Jae Hong; Kim, Dong-Wan; Kim, Tae Woo

    2015-11-24

    The fusion between anaplastic lymphoma kinase (ALK) and echinoderm microtubule-associated protein-like 4 (EML4) is a causative factor in a unique subset of patients with non-small cell lung carcinoma (NSCLC). Although the inhibitor crizotinib, as it blocks the kinase activity of the resulting EML4-ALK fusion protein, displays remarkable initial responses, a fraction of NSCLC cases eventually become resistant to crizotinib by acquiring mutations in the ALK domain or activating bypass pathways via EGFR, KIT, or KRAS. Cancer stem cell (CSC) theory provides a plausible explanation for acquisition of tumorigenesis and resistance. However, the question as to whether EML4-ALK-driven tumorigenesis is linked with the stem-like property and whether the stemness is an effective target in controlling EML4-ALK+ NSCLC including crizotinib-resistant NSCLC cells has not been addressed. Here, we report that stem-like properties stem from ALK activity in EML4-ALK+ NSCLC cells. Notably, treatment with rapamycin, a CSC targeting agent, attenuates stem-like phenotypes of the EML4-ALK+ cells, which increased capability of tumor formation and higher expression of stemness-associated molecules such as ALDH, NANOG, and OCT4. Importantly, combinational treatment with rapamycin and crizotinib leads to synergistic anti-tumor effects on EML4-ALK+ NSCLC cells as well as on those resistant to crizotinib. Thus, we provide a proof of principle that targeting stemness would be a novel strategy to control intractable EML4-ALK+ NSCLC.

  9. The Transcriptional Targets of Mutant FOXL2 in Granulosa Cell Tumours

    OpenAIRE

    2012-01-01

    BACKGROUND: Despite their distinct biology, granulosa cell tumours (GCTs) are treated the same as other ovarian tumours. Intriguingly, a recurring somatic mutation in the transcription factor Forkhead Box L2 (FOXL2) 402C>G has been found in nearly all GCTs examined. This investigation aims to identify the pathogenicity of mutant FOXL2 by studying its altered transcriptional targets. METHODS: The expression of mutant FOXL2 was reduced in the GCT cell line KGN, and wildtype and mutant FOXL2 wer...

  10. Combination therapy targeting both cancer stem-like cells and bulk tumor cells for improved efficacy of breast cancer treatment.

    Science.gov (United States)

    Wang, Tao; Narayanaswamy, Radhika; Ren, Huilan; Torchilin, Vladimir P

    2016-06-01

    Many types of tumors are organized in a hierarchy of heterogeneous cell populations. The cancer stem-like cells (CSCs) hypothesis suggests that tumor development and metastasis are driven by a minority population of cells, which are responsible for tumor initiation, growth and recurrences. The inability to efficiently eliminate CSCs during chemotherapy, together with CSCs being highly tumorigenic and invasive, may result in treatment failure due to cancer relapse and metastases. CSCs are emerging as a promising target for the development of translational cancer therapies. Ideal panacea for cancer would kill all malignant cells, including CSCs and bulk tumor cells. Since both chemotherapy and CSCs-specific therapy are insufficient to cure cancer, we propose combination therapy with CSCs-targeted agents and chemotherapeutics for improved breast cancer treatment. We generated in vitro mammosphere of 2 breast cancer cell lines, and demonstrated ability of mammospheres to grow and enrich cancer cells with stem-like properties, including self-renewal, multilineage differentiation and enrichment of cells expressing breast cancer stem-like cell biomarkers CD44(+)/CD24(-/low). The formation of mammospheres was significantly inhibited by salinomycin, validating its pharmacological role against the cancer stem-like cells. In contrast, paclitaxel showed a minimal effect on the proliferation and growth of breast cancer stem-like cells. While combination therapies of salinomycin with conventional chemotherapy (paclitaxel or lipodox) showed a potential to improve tumor cell killing, different subtypes of breast cancer cells showed different patterns in response to the combination therapies. While optimization of combination therapy is warranted, the design of combination therapy should consider phenotypic attributes of breast cancer types.

  11. MiR-223 suppresses cell proliferation by targeting IGF-1R.

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    Cheng You Jia

    Full Text Available To study the roles of microRNA-223 (miR-223 in regulation of cell growth, we established a miR-223 over-expression model in HeLa cells infected with miR-223 by Lentivirus pLL3.7 system. We observed in this model that miR-223 significantly suppressed the proliferation, growth rate, colony formation of HeLa cells in vitro, and in vivo tumorigenicity or tumor formation in nude mice. To investigate the mechanisms involved, we scanned and examined the potential and putative target molecules of miR-223 by informatics, quantitative PCR and Western blot, and found that insulin-like growth factor-1 receptor (IGF-1R was the functional target of miR-223 inhibition of cell proliferation. Targeting IGF-1R by miR-223 was not only seen in HeLa cells, but also in leukemia and hepatoma cells. The downstream pathway, Akt/mTOR/p70S6K, to which the signal was mediated by IGF-1R, was inhibited as well. The relative luciferase activity of the reporter containing wild-type 3'UTR(3'untranslated region of IGF-1R was significantly suppressed, but the mutant not. Silence of IGF-1R expression by vector-based short hairpin RNA resulted in the similar inhibition with miR-223. Contrarily, rescued IGF-1R expression in the cells that over-expressed miR-223, reversed the inhibition caused by miR-223 via introducing IGF-1R cDNA that didn't contain the 3'UTR. Meanwhile, we also noted that miR-223 targeted Rasa1, but the downstream molecules mediated by Rasa1 was neither targeted nor regulated. Therefore we believed that IGF-1R was the functional target for miR-223 suppression of cell proliferation and its downstream PI3K/Akt/mTOR/p70S6K pathway suppressed by miR-223 was by targeting IGF-1R.

  12. Smart Cancer Cell Targeting Imaging and Drug Delivery System by Systematically Engineering Periodic Mesoporous Organosilica Nanoparticles.

    Science.gov (United States)

    Lu, Nan; Tian, Ying; Tian, Wei; Huang, Peng; Liu, Ying; Tang, Yuxia; Wang, Chunyan; Wang, Shouju; Su, Yunyan; Zhang, Yunlei; Pan, Jing; Teng, Zhaogang; Lu, Guangming

    2016-02-10

    The integration of diagnosis and therapy into one nanoplatform, known as theranostics, has attracted increasing attention in the biomedical areas. Herein, we first present a cancer cell targeting imaging and drug delivery system based on engineered thioether-bridged periodic mesoporous organosilica nanoparticles (PMOs). The PMOs are stably and selectively conjugated with near-infrared fluorescence (NIRF) dye Cyanine 5.5 (Cy5.5) and anti-Her2 affibody on the outer surfaces to endow them with excellent NIRF imaging and cancer targeting properties. Also, taking the advantage of the thioether-group-incorporated mesopores, the release of chemotherapy drug doxorubicin (DOX) loaded in the PMOs is responsive to the tumor-related molecule glutathione (GSH). The drug release percentage reaches 84.8% in 10 mM of GSH solution within 24 h, which is more than 2-fold higher than that without GSH. In addition, the drug release also exhibits pH-responsive, which reaches 53.6% at pH 5 and 31.7% at pH 7.4 within 24 h. Confocal laser scanning microscopy and flow cytometry analysis demonstrate that the PMOs-based theranostic platforms can efficiently target to and enter Her2 positive tumor cells. Thus, the smart imaging and drug delivery nanoplatforms induce high tumor cell growth inhibition. Meanwhile, the Cy5.5 conjugated PMOs perform great NIRF imaging ability, which could monitor the intracellular distribution, delivery and release of the chemotherapy drug. In addition, cell viability and histological assessments show the engineered PMOs have good biocompatibility, further encouraging the following biomedical applications. Over all, the systemically engineered PMOs can serve as a novel cancer cell targeting imaging and drug delivery platform with NIRF imaging, GSH and pH dual-responsive drug release, and high tumor cell targeting ability.

  13. The transcriptional targets of mutant FOXL2 in granulosa cell tumours.

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    Roseanne Rosario

    Full Text Available BACKGROUND: Despite their distinct biology, granulosa cell tumours (GCTs are treated the same as other ovarian tumours. Intriguingly, a recurring somatic mutation in the transcription factor Forkhead Box L2 (FOXL2 402C>G has been found in nearly all GCTs examined. This investigation aims to identify the pathogenicity of mutant FOXL2 by studying its altered transcriptional targets. METHODS: The expression of mutant FOXL2 was reduced in the GCT cell line KGN, and wildtype and mutant FOXL2 were overexpressed in the GCT cell line COV434. Total RNA was hybridised to Affymetrix U133 Plus 2 microarrays. Comparisons were made between the transcriptomes of control cells and cells altered by FOXL2 knockdown and overexpression, to detect potential transcriptional targets of mutant FOXL2. RESULTS: The overexpression of wildtype and mutant FOXL2 in COV434, and the silencing of mutant FOXL2 expression in KGN, has shown that mutant FOXL2 is able to differentially regulate the expression of many genes, including two well known FOXL2 targets, StAR and CYP19A. We have shown that many of the genes regulated by mutant FOXL2 are clustered into functional annotations of cell death, proliferation, and tumourigenesis. Furthermore, TGF-β signalling was found to be enriched when using the gene annotation tools GATHER and GeneSetDB. This enrichment was still significant after performing a robust permutation analysis. CONCLUSION: Given that many of the transcriptional targets of mutant FOXL2 are known TGF-β signalling genes, we suggest that deregulation of this key antiproliferative pathway is one way mutant FOXL2 contributes to the pathogenesis of adult-type GCTs. We believe this pathway should be a target for future therapeutic interventions, if outcomes for women with GCTs are to improve.

  14. Improved Activation toward Primary Colorectal Cancer Cells by Antigen-Specific Targeting Autologous Cytokine-Induced Killer Cells

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    Claudia Schlimper

    2012-01-01

    Full Text Available Adoptive therapy of malignant diseases with cytokine-induced killer (CIK cells showed promise in a number of trials; the activation of CIK cells from cancer patients towards their autologous cancer cells still needs to be improved. Here, we generated CIK cells ex vivo from blood lymphocytes of colorectal cancer patients and engineered those cells with a chimeric antigen receptor (CAR with an antibody-defined specificity for carcinoembryonic antigen (CEA. CIK cells thereby gained a new specificity as defined by the CAR and showed increase in activation towards CEA+ colon carcinoma cells, but less in presence of CEA− cells, indicated by increased secretion of proinflammatory cytokines. Redirected CIK activation was superior by CAR-mediated CD28-CD3ζ than CD3ζ signaling only. CAR-engineered CIK cells from colon carcinoma patients showed improved activation against their autologous, primary carcinoma cells from biopsies resulting in more efficient tumour cell lysis. We assume that adoptive therapy with CAR-modified CIK cells shows improved selectivity in targeting autologous tumour lesions.

  15. Targeting cyclin B1 inhibits proliferation and sensitizes breast cancer cells to taxol

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    Strebhardt Klaus

    2008-12-01

    Full Text Available Abstract Background Cyclin B1, the regulatory subunit of cyclin-dependent kinase 1 (Cdk1, is essential for the transition from G2 phase to mitosis. Cyclin B1 is very often found to be overexpressed in primary breast and cervical cancer cells as well as in cancer cell lines. Its expression is correlated with the malignancy of gynecological cancers. Methods In order to explore cyclin B1 as a potential target for gynecological cancer therapy, we studied the effect of small interfering RNA (siRNA on different gynecological cancer cell lines by monitoring their proliferation rate, cell cycle profile, protein expression and activity, apoptosis induction and colony formation. Tumor formation in vivo was examined using mouse xenograft models. Results Downregulation of cyclin B1 inhibited proliferation of several breast and cervical cancer cell lines including MCF-7, BT-474, SK-BR-3, MDA-MB-231 and HeLa. After combining cyclin B1 siRNA with taxol, we observed an increased apoptotic rate accompanied by an enhanced antiproliferative effect in breast cancer cells. Furthermore, control HeLa cells were progressively growing, whereas the tumor growth of HeLa cells pre-treated with cyclin B1 siRNA was strongly inhibited in nude mice, indicating that cyclin B1 is indispensable for tumor growth in vivo. Conclusion Our data support the notion of cyclin B1 being essential for survival and proliferation of gynecological cancer cells. Concordantly, knockdown of cyclin B1 inhibits proliferation in vitro as well as in vivo. Moreover, targeting cyclin B1 sensitizes breast cancer cells to taxol, suggesting that specific cyclin B1 targeting is an attractive strategy for the combination with conventionally used agents in gynecological cancer therapy.

  16. B-cell-targeted therapy for systemic lupus erythematosus: an update.

    Science.gov (United States)

    Ding, Changhai; Foote, Simon; Jones, Graeme

    2008-01-01

    Systemic lupus erythematosus (SLE) is a classic autoimmune disease characterized by a myriad of immune system aberrations, most likely resulting from pathogenic autoantibody production, immune complex deposition, and subsequent end-organ damage. B cells play a key role in the pathogenesis; therefore, B-cell-targeted therapies, including B-cell depletion and blockage of B-cell survival factors such as B-lymphocyte stimulator (BLyS), are potential therapeutic targets for SLE. In uncontrolled clinical trials from approximately 20 studies, rituximab--a mouse-human chimeric anti-CD20 monoclonal antibody that effectively depletes B cells--has been demonstrated to reduce disease activity and decrease serum autoantibodies, with a clinical response of 86% in a case series of approximately 400 SLE patients with refractory disease, with or without concomitant use of cyclophosphamide. Epratuzumab, a humanized anti-CD22 monoclonal antibody that partially depletes B cells, has also been shown to reduce disease activity but not to decrease autoantibody levels in patients with moderately active SLE. Randomized controlled phase I/II trials in patients with active SLE have documented that belimumab, a humanized anti-BLyS monoclonal antibody, reduces B-cell numbers, inhibits disease activity and decreases anti-double-stranded DNA autoantibody in SLE patients. All these therapies are well tolerated, but accompanying infectious complications have been observed. Other B-cell-targeted therapies such as 'humanized' monoclonal antibodies to CD20 (e.g. ocrelizumab) and agents that interrupt B-cell/T-cell interactions also have potential, and the efficacy of these, along with rituximab, belimumab and epratuzumab, needs to be determined by randomized controlled trials.

  17. Repair at single targeted DNA double-strand breaks in pluripotent and differentiated human cells.

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    Hua Fung

    Full Text Available Differences in ex vivo cell culture conditions can drastically affect stem cell physiology. We sought to establish an assay for measuring the effects of chemical, environmental, and genetic manipulations on the precision of repair at a single DNA double-strand break (DSB in pluripotent and somatic human cells. DSBs in mammalian cells are primarily repaired by either homologous recombination (HR or nonhomologous end-joining (NHEJ. For the most part, previous studies of DSB repair in human cells have utilized nonspecific clastogens like ionizing radiation, which are highly nonphysiologic, or assayed repair at randomly integrated reporters. Measuring repair after random integration is potentially confounded by locus-specific effects on the efficiency and precision of repair. We show that the frequency of HR at a single DSB differs up to 20-fold between otherwise isogenic human embryonic stem cells (hESCs based on the site of the DSB within the genome. To overcome locus-specific effects on DSB repair, we used zinc finger nucleases to efficiently target a DSB repair reporter to a safe-harbor locus in hESCs and a panel of somatic human cell lines. We demonstrate that repair at a targeted DSB is highly precise in hESCs, compared to either the somatic human cells or murine embryonic stem cells. Differentiation of hESCs harboring the targeted reporter into astrocytes reduces both the efficiency and precision of repair. Thus, the phenotype of repair at a single DSB can differ based on either the site of damage within the genome or the stage of cellular differentiation. Our approach to single DSB analysis has broad utility for defining the effects of genetic and environmental modifications on repair precision in pluripotent cells and their differentiated progeny.

  18. Stable gene targeting in human cells using single-strand oligonucleotides with modified bases.

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    Xavier Rios

    Full Text Available Recent advances allow multiplexed genome engineering in E. coli, employing easily designed oligonucleotides to edit multiple loci simultaneously. A similar technology in human cells would greatly expedite functional genomics, both by enhancing our ability to test how individual variants such as single nucleotide polymorphisms (SNPs are related to specific phenotypes, and potentially allowing simultaneous mutation of multiple loci. However, oligo-mediated targeting of human cells is currently limited by low targeting efficiencies and low survival of modified cells. Using a HeLa-based EGFP-rescue reporter system we show that use of modified base analogs can increase targeting efficiency, in part by avoiding the mismatch repair machinery. We investigate the effects of oligonucleotide toxicity and find a strong correlation between the number of phosphorothioate bonds and toxicity. Stably EGFP-corrected cells were generated at a frequency of ~0.05% with an optimized oligonucleotide design combining modified bases and reduced number of phosphorothioate bonds. We provide evidence from comparative RNA-seq analysis suggesting cellular immunity induced by the oligonucleotides might contribute to the low viability of oligo-corrected cells. Further optimization of this method should allow rapid and scalable genome engineering in human cells.

  19. Heme oxygenase-1 promotes Caco-2 cell proliferation and migration by targeting CTNND1

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; LIU Yu-lin; CHEN Guang-xiang; CUI Bin; WANG Jin-shen; SHI Yu-long; LI Le-ping

    2013-01-01

    Background Heme oxygenase-1 (HO-1) can be induced by inflammatory cytokines,oxidation,ischemia,hypoxia,and endotoxins.As a "graft survival protective gene," HO-1 is a hot spot in organ transplantation research.However,the role of HO-1 gene expression in the function of human colon adenocarcinoma cell line (Caco-2) cells has not been reported previously.Methods The role of HO-1 in the proliferation and migration of Caco-2 cells was analyzed using a stable HO-1 expression plasmid.We constructed a recombinant adeno-associated virus plasmid containing the HO-1 gene,heme oxygenase 1 (HMOX1),which was transfected into Caco-2 intestinal cells.We identified a number of target genes by global microarray analysis combined with real-time polymerase chain reaction (PCR) and chromatin immunoprecipitation assay.Results Our results showed that significant HO-1 upregulation was demonstrated in the Caco-2 cells after HO-1 transfection.Restoration of HO-1 expression promoted proliferation and invasion in vitro.The CTNND1 gene,a member of the armadillo protein family,was identified as a direct HO-1 target gene.Conclusion Overexpression of HO-1 promotes Caco-2 cell proliferation and migration by targeting the CTNND1 gene.

  20. Screening and target identification of bioactive compounds that modulate cell migration and autophagy.

    Science.gov (United States)

    Tashiro, Etsu; Imoto, Masaya

    2016-08-01

    Cell migration is a fundamental step for embryonic development, wound repair, immune responses, and tumor cell invasion and metastasis. It is well known that protrusive structures, namely filopodia and lamellipodia, can be observed at the leading edge of migrating cells. The formation of these structures is necessary for cell migration; however, the molecular mechanisms behind the formation of these structures remain largely unclear. Therefore, bioactive compounds that modulate protrusive structures are extremely powerful tools for studying the mechanisms behind the formation of these structures and subsequent cell migration. Therefore, we have screened for bioactive compounds that inhibit the formation of filopodia, lamellipodia, or cell migration from natural products, and attempted to identify the target molecules of our isolated compounds. Additionally, autophagy is a bulk, non-specific protein degradation system that is involved in the pathogenesis of cancer and neurodegenerative disorders. Recent extensive studies have revealed the molecular mechanisms of autophagy, however, they also remain largely unclear. Thus, we also have screened for bioactive compounds that modulate autophagy, and identified the target molecules. In the present article, we introduce the phenotypic screening system and target identification of four bioactive compounds.

  1. Engineering of Systematic Elimination of a Targeted Chromosome in Human Cells

    Directory of Open Access Journals (Sweden)

    Hiroshi Sato

    2017-01-01

    Full Text Available Embryonic trisomy leads to abortion or congenital genetic disorders in humans. The most common autosomal chromosome abnormalities are trisomy of chromosomes 13, 18, and 21. Although alteration of gene dosage is thought to contribute to disorders caused by extra copies of chromosomes, genes associated with specific disease phenotypes remain unclear. To generate a normal cell from a trisomic cell as a means of etiological analysis or candidate therapy for trisomy syndromes, we developed a system to eliminate a targeted chromosome from human cells. Chromosome 21 was targeted by integration of a DNA cassette in HeLa cells that harbored three copies of chromosome 21. The DNA cassette included two inverted loxP sites and a herpes simplex virus thymidine kinase (HSV-tk gene. This system causes missegregation of chromosome 21 after expression of Cre recombinase and subsequently enables the selection of cells lacking the chromosome by culturing in a medium that includes ganciclovir (GCV. Cells harboring only two copies of chromosome 21 were efficiently induced by transfection of a Cre expression vector, indicating that this approach is useful for eliminating a targeted chromosome.

  2. Butyrate Induced Cell Cycle Arrest in Bovine Cells through Targeting Gene Expression relevance to DNA Replication Apparatus

    Science.gov (United States)

    Using both real-time RT-PCR and Western blot analysis in bovine kidney epithelial cells, we systematically investigated the gene expression relevance to DNA replication apparatus targeted by butyrate. The real-time PCR and Western blot data generally confirmed the microarray analysis. From the quan...

  3. A clinically attainable dose of L-asparaginase targets glutamine addiction in lymphoid cell lines.

    Science.gov (United States)

    Sugimoto, Koichi; Suzuki, Hiroshi I; Fujimura, Tsutomu; Ono, Asami; Kaga, Naoko; Isobe, Yasushi; Sasaki, Makoto; Taka, Hikari; Miyazono, Kohei; Komatsu, Norio

    2015-11-01

    L-asparaginase (L-ASNase) is an important branch of chemotherapy for acute lymphoblastic leukemia (ALL) and some types of non-Hodgkin's lymphoma, including natural killer (NK)-cell lymphoma. Although it mediates hydrolysis of asparagine (Asn) and glutamine (Gln), which are variably required for cancer cell survival, the relative contribution of Asn and Gln depletion to the anti-tumor activity in therapeutic doses is unclear in ALL and malignant lymphoma. Here we demonstrate that L-ASNase exerts cytotoxicity through targeting the Gln addiction phenotype in lymphoid cell lines. A clinically attainable intermediate dose of L-ASNase induced massive apoptosis in ALL Jurkat and mantle cell lymphoma Jeko cell lines, while a low dose of L-ASNase effectively killed NK-cell lymphoma cells. In the lymphoid cell lines Jurkat and Jeco, deprivation of Gln but not Asn specifically suppressed cell growth and survival, and phenocopied the action of L-ASNase. L-ASNase treatment and Gln deprivation dramatically disrupted the refilling of the tricarboxylic acid (TCA) cycle by intracellular glutamate (Glu) and disturbed the mitochondrial integrity, which were alleviated by various anaplerotic TCA cycle intermediates, suggesting a direct contribution of glutaminase activity of L-ASNase. The action of L-ASNase differs between Jurkat cells and NK-cell lymphoma cells, according to their dependence on Gln and Asn. Furthermore, we observed that high expression of glutaminase GLS1 is associated with increased sensivity to L-ASNase in pediatric B lineage ALL. Our results redefine L-ASNase as a therapeutic agent targeting Gln addiction in certain lymphoid cells and offer an additional basis for predicting L-ASNase sensitivity and engineering selective L-ASNase derivatives for leukemia and lymphoma.

  4. Exosomes from B cells and Dendritic cells: mechanisms of formation, secretion and targeting

    NARCIS (Netherlands)

    Buschow, S.I.

    2006-01-01

    Many cell types, including dendritic cells (DC) and B cells, secrete small vesicles called exosomes. Exosomes from immune cells are thought to have immuno-regulatory functions but their precise role remains unresolved. The aim of the studies presented in this thesis was to get more insight into the

  5. Targeting of peptide conjugated magnetic nanoparticles to urokinase plasminogen activator receptor (uPAR) expressing cells

    Science.gov (United States)

    Hansen, Line; Unmack Larsen, Esben Kjær; Nielsen, Erik Holm; Iversen, Frank; Liu, Zhuo; Thomsen, Karen; Pedersen, Michael; Skrydstrup, Troels; Nielsen, Niels Chr.; Ploug, Michael; Kjems, Jørgen

    2013-08-01

    Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific targeting peptide onto polyethylene glycol (PEG) coated USPIO nanoparticles by click chemistry resulted in a five times higher uptake in vitro in a uPAR positive cell line compared to nanoparticles carrying a non-binding control peptide. In accordance with specific receptor-mediated recognition, a low uptake was observed in the presence of an excess of ATF, a natural ligand for uPAR. The uPAR specific magnetic nanoparticles can potentially provide a useful supplement for tumor patient management when combined with MRI and drug delivery.Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific

  6. Induction of apoptosis in human cancer cells by targeting mitochondria with gold nanoparticles

    Science.gov (United States)

    Mkandawire, M. M.; Lakatos, M.; Springer, A.; Clemens, A.; Appelhans, D.; Krause-Buchholz, U.; Pompe, W.; Rödel, G.; Mkandawire, M.

    2015-06-01

    A major challenge in designing cancer therapies is the induction of cancer cell apoptosis, although activation of intrinsic apoptotic pathways by targeting gold nanoparticles to mitochondria is promising. We report an in vitro procedure targeting mitochondria with conjugated gold nanoparticles and investigating effects on apoptosis induction in the human breast cancer cell line Jimt-1. Gold nanoparticles were conjugated to a variant of turbo green fluorescent protein (mitoTGFP) harbouring an amino-terminal mitochondrial localization signal. Au nanoparticle conjugates were further complexed with cationic maltotriose-modified poly(propylene imine) third generation dendrimers. Fluorescence and transmission electron microscopy revealed that Au nanoparticle conjugates were directed to mitochondria upon transfection, causing partial rupture of the outer mitochondrial membrane, triggering cell death. The ability to target Au nanoparticles into mitochondria of breast cancer cells and induce apoptosis reveals an alternative application of Au nanoparticles in photothermal therapy of cancer.A major challenge in designing cancer therapies is the induction of cancer cell apoptosis, although activation of intrinsic apoptotic pathways by targeting gold nanoparticles to mitochondria is promising. We report an in vitro procedure targeting mitochondria with conjugated gold nanoparticles and investigating effects on apoptosis induction in the human breast cancer cell line Jimt-1. Gold nanoparticles were conjugated to a variant of turbo green fluorescent protein (mitoTGFP) harbouring an amino-terminal mitochondrial localization signal. Au nanoparticle conjugates were further complexed with cationic maltotriose-modified poly(propylene imine) third generation dendrimers. Fluorescence and transmission electron microscopy revealed that Au nanoparticle conjugates were directed to mitochondria upon transfection, causing partial rupture of the outer mitochondrial membrane, triggering cell

  7. Targeting of peptide conjugated magnetic nanoparticles to urokinase plasminogen activator receptor (uPAR) expressing cells

    DEFF Research Database (Denmark)

    Hansen, Line; Unmack Larsen, Esben Kjær; Nielsen, Erik Holm

    2013-01-01

    Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted...... towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor...... to nanoparticles carrying a non-binding control peptide. In accordance with specific receptor-mediated recognition, a low uptake was observed in the presence of an excess of ATF, a natural ligand for uPAR. The uPAR specific magnetic nanoparticles can potentially provide a useful supplement for tumor patient...

  8. Molecular targeted therapy in the treatment of advanced stage non-small cell lung cancer (NSCLC).

    Science.gov (United States)

    Kumarakulasinghe, Nesaretnam Barr; van Zanwijk, Nico; Soo, Ross A

    2015-04-01

    Historically, patients with advanced stage non-small cell lung cancer (NSCLC) were treated with chemotherapy alone, but a therapeutic plateau has been reached. Advances in the understanding of molecular genetics have led to the recognition of multiple molecularly distinct subsets of NSCLC. This in turn has led to the development of rationally directed molecular targeted therapy, leading to improved clinical outcomes. Tumour genotyping for EGFR mutations and ALK rearrangement has meant chemotherapy is no longer given automatically as first-line treatment but reserved for when patients do not have a 'druggable' driver oncogene. In this review, we will address the current status of clinically relevant driver mutations and emerging new molecular subsets in lung adenocarcinoma and squamous cell carcinoma, and the role of targeted therapy and mechanisms of acquired resistance to targeted therapy.

  9. Cancer Stem Cells: Targeting the Roots of Cancer, Seeds of Metastasis, and Sources of Therapy Resistance

    Science.gov (United States)

    Adorno-Cruz, Valery; Kibria, Golam; Liu, Xia; Doherty, Mary; Junk, Damian J.; Guan, Dongyin; Hubert, Chris; Venere, Monica; Mulkearns-Hubert, Erin; Sinyuk, Maksim; Alvarado, Alvaro; Caplan, Arnold I.; Rich, Jeremy; Gerson, Stanton L.; Lathia, Justin; Liu, Huiping

    2015-01-01

    With the goal to remove the roots of cancer, eliminate metastatic seeds, and overcome therapy resistance, the 2014 inaugural International Cancer Stem Cell (CSC) Conference at Cleveland, OH, convened together over 320 investigators, including 55 invited world-class speakers, 25 short oral presenters, and 100 poster presenters, to gain an in-depth understanding of CSCs and explore therapeutic opportunities targeting CSCs. The meeting enabled intriguing discussions on several topics including: genetics and epigenetics; cancer origin and evolution; microenvironment and exosomes; metabolism and inflammation; metastasis and therapy resistance; single cell and heterogeneity; plasticity and reprogramming; as well as other new concepts. Reports of clinical trials targeting CSCs emphasized the urgent need for strategically designing combinational CSC-targeting therapies against cancer. PMID:25604264

  10. Schwann cells express erythropoietin receptor and represent a major target for Epo in peripheral nerve injury.

    Science.gov (United States)

    Li, Xiaoqing; Gonias, Steven L; Campana, W Marie

    2005-09-01

    Erythropoietin (Epo) expresses potent neuroprotective activity in the peripheral nervous system; however, the underlying mechanism remains incompletely understood. In this study, we demonstrate that Epo is upregulated in sciatic nerve after chronic constriction injury (CCI) and crush injury in rats, largely due to local Schwann cell production. In uninjured and injured nerves, Schwann cells also express Epo receptor (EpoR), and its expression is increased during Wallerian degeneration. CCI increased the number of Schwann cells at the injury site and the number was further increased by exogenously administered recombinant human Epo (rhEpo). To explore the activity of Epo in Schwann cells, primary cultures were established. These cells expressed cell-surface Epo receptors, with masses of 71 and 62 kDa, as determined by surface protein biotinylation and affinity precipitation. The 71-kDa species was rapidly but transiently tyrosine-phosphorylated in response to rhEpo. ERK/MAP kinase was also activated in rhEpo-treated Schwann cells; this response was blocked by pharmacologic antagonism of JAK-2. RhEpo promoted Schwann cell proliferation, as determined by BrdU incorporation. Cell proliferation was ERK/MAP kinase-dependent. These results support a model in which Schwann cells are a major target for Epo in injured peripheral nerves, perhaps within the context of an autocrine signaling pathway. EpoR-induced cell signaling and Schwann cell proliferation may protect injured peripheral nerves and promote regeneration.

  11. Targeting Foxp3+ regulatory T cells-related immunosuppression for cancer immunotherapy

    Institute of Scientific and Technical Information of China (English)

    FENG Li-li; WANG Xin

    2010-01-01

    Objective To review the current research into Foxp3+ regulatory T cells (Treg) cell surface molecules, plasticity of Treg cells and mechanisms of Treg cell suppression and to explore the possibilities to interfere in Treg cell suppression of anti-tumor immunity.Data sources A literature search of all English articles was performed on the online electronic PubMed database dated 1995 to 2010. The keywords searched included: CD4+CD25+Foxp3+ regulatory T lymphocytes, cancer, and immunotherapy. After finding relevant articles within these search limits, a manual search was conducted through the references from these articles.Study selection Articles regarding the role of Treg cells in tumor immunity and the utility of Treg cells in tumor immunotherapy.Results The results show that significant numbers of Treg cells are found in many tumors and it has been shown that the number of tumor infiltrating Treg cells correlates with adverse clinic outcomes. Treg cells are emerging as a key component of acquired tolerance to tumors.Conclusions Several mechanisms of immunosuppression can be mediated by Treg cell function. Distinct immunosuppressive molecules expressed by Treg cells or diverse molecules related to Treg induction or migration represent potential drug targets for caner immunotherapy.

  12. Telomerase inhibition effectively targets mouse and human AML stem cells and delays relapse following chemotherapy

    DEFF Research Database (Denmark)

    Bruedigam, Claudia; Bagger, Frederik O; Heidel, Florian H;

    2014-01-01

    Acute myeloid leukemia (AML) is an aggressive and lethal blood cancer maintained by rare populations of leukemia stem cells (LSCs). Selective targeting of LSCs is a promising approach for treating AML and preventing relapse following chemotherapy, and developing such therapeutic modalities is a key...

  13. Multidisciplinary management of metastatic renal cell carcinoma in the era of targeted therapies.

    NARCIS (Netherlands)

    Escudier, B.; Osanto, S.; Ljungberg, B.; Porta, C.; Wagstaff, J.; Mulders, P.F.A.; Gore, M.; Bex, A.; Bellmunt, J.; Bracarda, S.; Franklin, A.; Honore, P.H.; Ravaud, A.; Steijn, J.; Aziz, Z.; Akaza, H.

    2012-01-01

    The use of targeted agents to treat metastatic renal cell carcinoma (mRCC) has significantly extended progression-free and overall survival but raises issues relating to the long-term delivery of care and the sustained monitoring of efficacy and toxicities, certain of which have not previously been

  14. Modular Assembly of Cell-targeting Devices Based on an Uncommon G-quadruplex Aptamer

    DEFF Research Database (Denmark)

    Opazo, Felipe; Eiden, Laura; Hansen, Line;

    2015-01-01

    cells. We further optimized this aptamer to a highly versatile and stable minimized version. The minimized aptamer can be easily equipped with different functionalities like quantum dots, organic dyes, or even a second different aptamer domain yielding a bi-paratopic aptamer. Although the target...

  15. Accessing Structurally Diverse Near-Infrared Cyanine Dyes for Folate Receptor-Targeted Cancer Cell Staining.

    Science.gov (United States)

    König, Sandra G; Krämer, Roland

    2017-03-24

    Folate receptor (FR) targeting is one of the most promising strategies for the development of small-molecule based cancer imaging agents since the FR is highly overexpressed on the surface of many cancer cell types. FR-targeted conjugates of NIR emissive cyanine dyes are in advanced clinical trials for fluorescence-guided surgery and are valuable research tools for optical molecular imaging in animal models. Only a small number of promising conjugates has been evaluated so far. Analysis of structure-performance relations to identify critical factors modulating the performance of targeted conjugates is essential for successful further optimization. This contribution addresses the need for convenient synthetic access to structurally diverse NIR-emissive cyanine dyes for conjugation with folic acid. Structural variations were introduced to readily available cyanine precursors in particular via C-C-coupling reactions including Suzuki- and (for the first time with these types of dyes) Sonogashira cross couplings. Photophysical properties such as absorbance maxima, brightness, and photostability are highly dependent on the molecular structure. Selected modified cyanines were conjugated to folic acid for cancer cell targeting. Several conjugates display a favorable combination of high fluorescence brightness and photostability with high affinity to FR positive cancer cells, and enable the selective imaging of these cells with low background.

  16. Live-attenuated measles virus vaccine targets dendritic cells and macrophages in muscle of nonhuman primates

    NARCIS (Netherlands)

    L.J. Rennick (Linda); R.D. de Vries (Rory); T.J. Carsillo (Thomas J.); K. Lemon (Ken); G. van Amerongen (Geert); M. Ludlow (Martin); D.T. Nguyen (Tien); S. Yüksel (Selma); R.J. Verbugh (Joyce); P. Haddock (Paula); S. McQuaid (Stephen); W.P. Duprex (Paul); R.L. de Swart (Rik)

    2015-01-01

    textabstractAlthough live-attenuated measles virus (MV) vaccines have been used successfully for over 50 years, the target cells that sustain virus replication in vivo are still unknown. We generated a reverse genetics system for the live-attenuated MV vaccine strain Edmonston- Zagreb (EZ), allowing

  17. The Uses and Future Prospects of Metabolomics and Targeted Metabolite Profiling in Cell Factory Development

    DEFF Research Database (Denmark)

    Harrison, Scott James; Herrgard, Markus

    2013-01-01

    The development of cell factories for the production of chemicals has traditionally relied on measurements of product metabolite titers to assess the performance of genetically manipulated strains. With the development of improved metabolomics and targeted metabolite profiling methods, these broa......The development of cell factories for the production of chemicals has traditionally relied on measurements of product metabolite titers to assess the performance of genetically manipulated strains. With the development of improved metabolomics and targeted metabolite profiling methods......, these broader measurements of the cellular metabolic state are now becoming part of the toolbox used to characterize cell factories. In this review we briefly summarize the benefits and challenges of global metabolomics and targeted metabolite profiling methods and discuss the application of these methods...... in both pathway discovery and cell factory engineering. We focus particularly on exploring the potential of global metabolomics to complement more traditional targeted methods. We conclude the review by discussing emerging trends in metabolomics and how these developments can aid the engineering of better...

  18. Endothelial cells internalize and degrade RGD-modified proteins developed for tumor vasculature targeting

    NARCIS (Netherlands)

    Schraaa, AJ; Kok, RJ; Berendsen, AD; Moorlag, HE; Bos, EJ; Meijer, DKF; de Leij, LFMH; Molema, G

    2002-01-01

    Tumor vasculature can be targeted by peptides containing an RGD (Arg-Gly-Asp) sequence, which bind to a p, and alpha(v)beta(5) integrins on angiogenic endothelial cells. By covalently attaching cyclic RGD-peptides (cRGDfK) to a protein backbone, we prepared a multivalent peptide-protein conjugate wi

  19. Efficient intracellular delivery of 5-fluorodeoxyuridine into colon cancer cells by targeted immunoliposomes

    NARCIS (Netherlands)

    Koning, GA; Kamps, JAAM; Scherphof, GL

    2002-01-01

    Immunoliposomes, liposomes with monoclonal antibodies attached, are being developed for targeting the anti-cancer drug 5-fluoro-2'-deoxyuridine (FUdR) to colon cancer cells. A monoclonal antibody against the rat colon carcinoma CC531 was covalently coupled to liposomes containing a dipalmitoylated d

  20. Targeted therapy of renal cell carcinoma: synergistic activity of cG250-TNF and IFNg.

    NARCIS (Netherlands)

    Bauer, S.; Oosterwijk-Wakka, J.C.; Adrian, N.; Oosterwijk, E.; Fischer, E.; Wuest, T.; Stenner, F.; Perani, A.; Cohen, L.; Knuth, A.; Divgi, C.; Jager, D.; Scott, A.M.; Ritter, G.; Old, L.J.; Renner, C.

    2009-01-01

    Immunotherapeutic targeting of G250/Carbonic anhydrase IX (CA-IX) represents a promising strategy for treatment of renal cell carcinoma (RCC). The well characterized human-mouse chimeric G250 (cG250) antibody has been shown in human studies to specifically enrich in CA-IX positive tumors and was cho

  1. Cell-specific targeting of lipid-based carriers for ODN and DNA

    NARCIS (Netherlands)

    Bartsch, M; Weeke-Klimp, AH; Meijer, DKF; Scherphof, GL; Kamps, JAAM

    2005-01-01

    It is well recognized that there is an urgent need for non-toxic systemically applicable vectors for biologically active nucleotides to fully exploit the current potential of molecular medicine in gene therapy. Cell-specific targeting of non-viral lipid-based carriers for ODN and DNA is a prerequisi

  2. A novel technology to target adenovirus vectors : application in cells involved in atherosclerosis

    NARCIS (Netherlands)

    Gras, Jan Cornelis Emile

    2007-01-01

    In this thesis a novel technology is described to target adenovirus vectors. Adenovirus vectors are powerful tools to modulate gene expression. The use of these vectors however, is hampered by the fact that many for gene therapy interesting cell types do not, or only at low levels express the CAR re

  3. MicroRNA-181b promotes ovarian cancer cell growth and invasion by targeting LATS2

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Ying; Gao, Yan, E-mail: gaoyanhdhos@126.com

    2014-05-09

    Highlights: • miR-181b is upregulated in human ovarian cancer tissues. • miR-181b promotes ovarian cancer cell proliferation and invasion. • LATS2 is a direct target of miR-181b. • LATS2 is involved in miR-181b-induced ovarian cancer cell growth and invasion. - Abstract: MicroRNAs (miRNAs) are strongly implicated in tumorigenesis and metastasis. In this study, we showed significant upregulation of miR-181b in ovarian cancer tissues, compared with the normal ovarian counterparts. Forced expression of miR-181b led to remarkably enhanced proliferation and invasion of ovarian cancer cells while its knockdown induced significant suppression of these cellular events. The tumor suppressor gene, LATS2 (large tumor suppressor 2), was further identified as a novel direct target of miR-181b. Specifically, miR-181b bound directly to the 3′-untranslated region (UTR) of LATS2 and suppressed its expression. Restoration of LATS2 expression partially reversed the oncogenic effects of miR-181b. Our results indicate that miR-181b promotes proliferation and invasion by targeting LATS2 in ovarian cancer cells. These findings support the utility of miR-181b as a potential diagnostic and therapeutic target for ovarian cancer.

  4. Targeting Hepatitis B Virus-Infected Cells with a T-Cell Receptor-Like Antibody▿ †

    Science.gov (United States)

    Sastry, Konduru S. R.; Too, Chien Tei; Kaur, Kaval; Gehring, Adam J.; Low, Lionel; Javiad, Alia; Pollicino, Teresa; Li, Li; Kennedy, Patrick T. F.; Lopatin, Uri; Macary, Paul A.; Bertoletti, Antonio

    2011-01-01

    Virus-specific CD8 T cells are activated when their T-cell receptors (TCRs) recognize the specific viral peptide/major histocompatibility complex (MHC) class I (pMHC) complexes present on the surface of infected cells. Antibodies able to recognize the specific pMHC can mimic TCR specificity and both represent a valuable biological tool to visualize pMHC complexes on infected cells and serve as a delivery system for highly targeted therapies. To evaluate these possibilities, we created a monoclonal antibody able to specifically recognize a hepatitis B virus (HBV) envelope epitope (Env at positions 183 to 91 [Env183-91]) presented by the HLA-A201 molecule, and we tested its ability to recognize HBV-infected hepatocytes and to deliver a cargo to a specific target. We demonstrate that this antibody detects and visualizes the processed product of HBV proteins produced in naturally HBV-infected cells, is not inhibited by soluble HBV proteins present in patient sera, and mediates the intracellular delivery of a fluorescent molecule to target cells. Additionally, compared to CD8 T cells specific for the same HBV epitope, the TCR-like antibody has both a superior sensitivity and a specificity focused on distinct amino acids within the epitope. These data demonstrate that a T-cell receptor-like antibody can be used to determine the quantitative relationship between HBV replication and specific antigen presentation to CD8 T cells and serves as a novel therapeutic delivery platform for personalized health care for HBV-infected patients. PMID:21159876

  5. Adenovirus Vectors Target Several Cell Subtypes of Mammalian Inner Ear In Vivo

    Science.gov (United States)

    Li, Wenyan; Shen, Jun

    2016-01-01

    Mammalian inner ear harbors diverse cell types that are essential for hearing and balance. Adenovirus is one of the major vectors to deliver genes into the inner ear for functional studies and hair cell regeneration. To identify adenovirus vectors that target specific cell subtypes in the inner ear, we studied three adenovirus vectors, carrying a reporter gene encoding green fluorescent protein (GFP) from two vendors or with a genome editing gene Cre recombinase (Cre), by injection into postnatal days 0 (P0) and 4 (P4) mouse cochlea through scala media by cochleostomy in vivo. We found three adenovirus vectors transduced mouse inner ear cells with different specificities and expression levels, depending on the type of adenoviral vectors and the age of mice. The most frequently targeted region was the cochlear sensory epithelium, including auditory hair cells and supporting cells. Adenovirus with GFP transduced utricular supporting cells as well. This study shows that adenovirus vectors are capable of efficiently and specifically transducing different cell types in the mammalian inner ear and provides useful tools to study inner ear gene function and to evaluate gene therapy to treat hearing loss and vestibular dysfunction. PMID:28116172

  6. Induction of mitochondrial dysfunction as a strategy for targeting tumour cells in metabolically compromised microenvironments.

    Science.gov (United States)

    Zhang, Xiaonan; Fryknäs, Mårten; Hernlund, Emma; Fayad, Walid; De Milito, Angelo; Olofsson, Maria Hägg; Gogvadze, Vladimir; Dang, Long; Påhlman, Sven; Schughart, Leoni A Kunz; Rickardson, Linda; D'Arcy, Padraig; Gullbo, Joachim; Nygren, Peter; Larsson, Rolf; Linder, Stig

    2014-01-01

    Abnormal vascularization of solid tumours results in the development of microenvironments deprived of oxygen and nutrients that harbour slowly growing and metabolically stressed cells. Such cells display enhanced resistance to standard chemotherapeutic agents and repopulate tumours after therapy. Here we identify the small molecule VLX600 as a drug that is preferentially active against quiescent cells in colon cancer 3-D microtissues. The anticancer activity is associated with reduced mitochondrial respiration, leading to bioenergetic catastrophe and tumour cell death. VLX600 shows enhanced cytotoxic activity under conditions of nutrient starvation. Importantly, VLX600 displays tumour growth inhibition in vivo. Our findings suggest that tumour cells in metabolically compromised microenvironments have a limited ability to respond to decreased mitochondrial function, and suggest a strategy for targeting the quiescent populations of tumour cells for improved cancer treatment.

  7. Targeting and molecular imaging of HepG2 cells using surface-functionalized gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Rathinaraj, Pierson [Auckland University of Technology, Institute of Biomedical Technologies (New Zealand); Lee, Kyubae; Choi, Yuri; Park, Soo-Young [Kyungpook National University, School of Applied Chemical Engineering, Graduate School (Korea, Republic of); Kwon, Oh Hyeong [Kumoh National Institute of Technology, Department of Polymer Science and Engineering (Korea, Republic of); Kang, Inn-Kyu, E-mail: ikkang@knu.ac.kr [Kyungpook National University, School of Applied Chemical Engineering, Graduate School (Korea, Republic of)

    2015-07-15

    Mercaptosuccinic acid (M)-conjugated gold nanoparticles (GM) were prepared and characterized by transmission electron microscope and dynamic light scattering. M was used to improve the monodispersity and non-specific intracellular uptake of nanoparticles. Lactobionic acid (L) was subsequently conjugated to the GM to target preferentially HepG2 cells (liver cancer cells) that express asialoglycoprotein receptors (ASGPR) on their membrane surfaces and facilitate the transit of nanoparticles across the cell membrane. The mean size of lactobionic acid-conjugated gold nanoparticle (GL) was approximately 10 ± 0.2 nm. Finally, the Atto 680 dye (A6) was coupled to the nanoparticles to visualize their internalization into HepG2 cells. The interaction of surface-modified gold nanoparticles with HepG2 cells was studied after culturing cells in media containing the GM or L-conjugated GM (GL)

  8. Identification and Targeting of Candidate Pre-Existing Lurker Cells that Give Rise to Castration-Resistant Prostate Cancer

    Science.gov (United States)

    2015-10-01

    progenitor cells as the pre-existing “lurker” cells in primary prostate tumors, to evaluate potential therapeutic targets in intermediate luminal... progenitor cells, and to define candidate biomarkers in intermediate luminal progenitor cells that can predict prognosis and response to hormonal therapy...15. SUBJECT TERMS Prostate, epithelial, Androgen-deprivation therapy, Castration-resistant prostate cancer, luminal progenitor , intermediate cell

  9. High throughput determination of TGFβ1/SMAD3 targets in A549 lung epithelial cells.

    Directory of Open Access Journals (Sweden)

    Yingze Zhang

    Full Text Available BACKGROUND: Transforming growth factor beta 1 (TGFβ1 plays a major role in many lung diseases including lung cancer, pulmonary hypertension, and pulmonary fibrosis. TGFβ1 activates a signal transduction cascade that results in the transcriptional regulation of genes in the nucleus, primarily through the DNA-binding transcription factor SMAD3. The objective of this study is to identify genome-wide scale map of SMAD3 binding targets and the molecular pathways and networks affected by the TGFβ1/SMAD3 signaling in lung epithelial cells. METHODOLOGY: We combined chromatin immunoprecipitation with human promoter region microarrays (ChIP-on-chip along with gene expression microarrays to study global transcriptional regulation of the TGFβ1/SMAD3 pathway in human A549 alveolar epithelial cells. The molecular pathways and networks associated with TGFβ1/SMAD3 signaling were identified using computational approaches. Validation of selected target gene expression and direct binding of SMAD3 to promoters were performed by quantitative real time RT-PCR and electrophoretic mobility shift assay on A549 and human primary lung epithelial cells. RESULTS AND CONCLUSIONS: Known TGFβ1 target genes such as SERPINE1, SMAD6, SMAD7, TGFB1 and LTBP3, were found in both ChIP-on-chip and gene expression analyses as well as some previously unrecognized targets such as FOXA2. SMAD3 binding of FOXA2 promoter and changed expression were confirmed. Computational approaches combining ChIP-on-chip and gene expression microarray revealed multiple target molecular pathways affected by the TGFβ1/SMAD3 signaling. Identification of global targets and molecular pathways and networks associated with TGFβ1/SMAD3 signaling allow for a better understanding of the mechanisms that determine epithelial cell phenotypes in fibrogenesis and carcinogenesis as does the discovery of the direct effect of TGFβ1 on FOXA2.

  10. MicroRNA-133a Inhibits Osteosarcoma Cells Proliferation and Invasion via Targeting IGF-1R

    Directory of Open Access Journals (Sweden)

    Guangnan Chen

    2016-02-01

    Full Text Available Background/Aims: MicroRNAs (miRNAs are a class of small noncoding RNAs that regulate gene expression by repressing translation or cleaving RNA transcripts in a sequence-specific manner. Downregulated microRNAs and their roles in cancer development have attracted much attention. A growing body of evidence showed that microRNA-133a (miR-133a has inhibitory effects on cell proliferation, migration, invasion, and metastasis of osteosarcoma. Methods: MiR-133a expression in human osteosarcoma cell lines and human normal osteoblastic cell line hFOB was investigated by real-time PCR (RT-PCR. The role of miR-133a in human osteosarcoma growth and invasion was assessed in cell lines in vitro and in vivo. Then, luciferase reporter assay validated IGF-1R as a downstream and functional target of miR-133a, and functional studies revealed that the anti-tumor effect of miR-133a was probably due to targeting and repressing of IGF-1R expression. Results: MiR-133a was lower expressed in human osteosarcoma cell lines than human normal osteoblastic cell line hFOB and its effect on inhibiting proliferation, invasion and metastasis is mediated by its direct interaction with the IGF-1R. Furthermore, the tumour-suppressive function of miR-133a probably contributed to inhibiting the activation AKT and ERK signaling pathway. Conclusion: MiR-133a suppresses osteosarcoma progression and metastasis by targeting IGF-1R in human osteosarcoma cells, providing a novel candidate prognostic factor and a potential anti-metastasis therapeutic target in osteosarcoma.

  11. Targeting SHP2 for EGFR inhibitor resistant non-small cell lung carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jie; Zeng, Li-Fan; Shen, Weihua [Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (United States); Turchi, John J. [Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (United States); Department of Medicine, Indiana University School of Medicine, Indianapolis (United States); Zhang, Zhong-Yin, E-mail: zyzhang@iu.edu [Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (United States)

    2013-10-04

    Highlights: •SHP2 is required for EGFR inhibitor resistant NSCLC H1975 cell proliferation. •SHP2 inhibitor blocks EGF-stimulated ERK1/2 activation and proliferation. •SHP2 inhibitor exhibits marked anti-tumor activity in H1975 xenograft mice. •SHP2 inhibitor synergizes with PI3K inhibitor in suppressing cell growth. •Targeting SHP2 represents a novel strategy for EGFR inhibitor resistant NSCLCs. -- Abstract: Targeted therapy with inhibitors of epidermal growth factor receptor (EGFR) has produced a noticeable benefit to non-small cell lung cancer (NSCLC) patients whose tumors carry activating mutations (e.g. L858R) in EGFR. Unfortunately, these patients develop drug resistance after treatment, due to acquired secondary gatekeeper mutations in EGFR (e.g. T790M). Given the critical role of SHP2 in growth factor receptor signaling, we sought to determine whether targeting SHP2 could have therapeutic value for EGFR inhibitor resistant NSCLC. We show that SHP2 is required for EGF-stimulated ERK1/2 phosphorylation and proliferation in EGFR inhibitor resistant NSCLC cell line H1975, which harbors the EGFR T790M/L858R double-mutant. We demonstrate that treatment of H1975 cells with II-B08, a specific SHP2 inhibitor, phenocopies the observed growth inhibition and reduced ERK1/2 activation seen in cells treated with SHP2 siRNA. Importantly, we also find that II-B08 exhibits marked anti-tumor activity in H1975 xenograft mice. Finally, we observe that combined inhibition of SHP2 and PI3K impairs both the ERK1/2 and PI3K/AKT signaling axes and produces significantly greater effects on repressing H1975 cell growth than inhibition of either protein individually. Collectively, these results suggest that targeting SHP2 may represent an effective strategy for treatment of EGFR inhibitor resistant NSCLCs.

  12. Research Status on Molecular Targeted Therapy for Squamous-Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Yanan LI

    2014-08-01

    Full Text Available Lung cancer is one of the world's highest morbidity and mortality disease in malignant tumors currently. Squamous-cell lung cancer (SQCLC is one of the most prevalent subtypes of lung cancer worldwide, after surgery, radiotherapy, chemotherapy and other comprehensive treatment, its 5-year survival rate is still below 15%. The current molecular targeted therapy plays an important role in the treatment of SQCLC, an urgent need to be more in-depth study. SQCLC molecular targeted therapy mainly epidermal growth factor receptor (EGFR, phosphoin-3-kinase catalytic alpha polypeptide (PIK3CA, fibroblast growth factor receptor 1 (FGFR1, discoidin domain receptor 2 (DDR2, phosphatase and tensin homolog deleted on chromosome ten (PTEN, BRAF, MET, insulin-like growth factor 1 receptor (IGF-1R and other as the target of the drug, some targeted drugs are being developed, and some targeted drugs have entered clinical trials. In recent years, with studies molecular targeted therapy in SQCLC, analysis of the development and trgeted therapy achieved substantial progress in improving the survival rate of SQCLC, and other research to improve the quality of life, make is possible to individualized targeted therapy of SQCLC.

  13. Changes in peripheral blood immune cells: their prognostic significance in metastatic renal cell carcinoma patients treated with molecular targeted therapy.

    Science.gov (United States)

    Kobayashi, Minoru; Kubo, Taro; Komatsu, Kenji; Fujisaki, Akira; Terauchi, Fumihito; Natsui, Shinsuke; Nukui, Akinori; Kurokawa, Shinsuke; Morita, Tatsuo

    2013-06-01

    Recently, novel molecular targeted agents markedly changed the treatment of renal cell carcinoma (RCC), with promising results. However, there is little understanding of how these agents affect immune cell populations in RCC, an immunogenic tumor. Therefore, we investigated the changes in the peripheral blood immune cells in 58 RCC patients during the first 4 weeks of treatment with sorafenib, sunitinib, everolimus, or temsirolimus and evaluated whether these changes were associated with clinical outcomes. The immunological parameters were the proportion of type-1 (Th1) and type-2 (Th2) T cells, regulatory T cells (Treg), mature dendritic cells, and the neutrophil-to-lymphocyte ratio (NLR). The changes in these immune cells varied with the agents and the clinical response, dichotomized by the median progression-free survival (PFS) time (PFS-short or PFS-long). A significant decrease in the Th1/Th2 ratio was seen after sunitinib treatment only in the PFS-short group, suggesting a shift toward Th2 that down-regulates host immunity. The NLRs indicative of the balance between host immunity and cancer-related inflammation were consistently lower in the PFS-long group than in the PFS-short group, suggesting that lower NLR is associated with better clinical response. Only sunitinib decreased NLR remarkably regardless of PFS status, which may favor anti-tumor immunity. When patients were dichotomized by the cutoff values, Th1/Th2 ratio was not associated with PFS in any targeted therapy, while lower pre-treatment NLR was associated with longer PFS in each targeted therapy. In addition, in RCC patients given sequential targeted therapy, those with a lower baseline NLR survived significantly longer compared with the counterparts. Moreover, those whose baseline NLR was sustained low during the initial therapy survived the longest. Our results suggest the diverse changes in host immune cells in RCC patients during targeted therapy. The changes in NLR during the early phase of

  14. Analysis of target genes induced by IL-13 cytotoxin in human glioblastoma cells.

    Science.gov (United States)

    Han, Jing; Yang, Liming; Puri, Raj K

    2005-03-01

    IL-13 cytotoxin comprised of IL-13 and a mutated form of Pseudomonas exotoxin (fusion protein termed IL-13-PE38QQR) has been shown to inhibit protein synthesis leading to necrotic and apoptotic cell death in glioblastoma cells that express high levels of interleukin-13 receptors (IL-13R). To identify target genes of cell death and other cellular genes with IL-13 receptors in glioblastoma cells, we utilized the cDNA microarrays to analyze global gene expression profiles after IL-13 cytotoxin and IL-13 treatment. IL-13 cytotoxin mediated cytotoxicity to U251 cells in a dose-dependent manner. Hierarchical cluster analysis of differentially expressed genes in U251 glioma cells at different time points after IL-13 cytotoxin treatment showed three major groups, each representing a specific expression pattern. Randomly selected differentially expressed genes from each group were confirmed by RT-PCR analysis. Most down-regulated genes belong to cell adhesion, motility, angiogenesis, DNA repair, and metabolic pathways. While up-regulated genes belong to cell cycle arrest, apoptosis, signaling and various metabolic pathways. Unexpectedly, at early time points, both IL-13 and IL-13 cytotoxin induced several genes belonging to different pathways most notably IL-8, DIO2, END1, and ALDH1A3 indicating that these genes are early response genes and their products may be associated with IL-13R. In addition, IL-13 cytotoxin induced IL-13Ralpha2 mRNA expression during the treatment in glioma cells. Our results indicate that novel cellular genes are involved with IL-13 receptors and that IL-13 cytotoxin induced cell death involves various target genes in human glioblastoma cells. On going studies will determine the role of associated genes and their products in the IL-13R functions in glioma cells.

  15. Molecular manipulation targeting regulation of dopaminergic differentiation and proliferation of neural stem cells or pluripotent stem cells.

    Science.gov (United States)

    Ding, Yin-Xiu; Wei, Li-Chun; Wang, Ya-Zhou; Cao, Rong; Wang, Xi; Chen, Liang-Wei

    2011-06-01

    Parkinson's disease (PD) is a severe deliberating neurological disease caused by progressive degenerative death of dopaminergic neurons in the substantia nigra of midbrain. While cell replacement strategy by transplantation of neural stem cells and inducement of dopaminergic neurons is recommended for the treatment of PD, understanding the differentiation mechanism and controlled proliferation of grafted stem cells remain major concerns in their clinical application. Here we review recent studies on molecular signaling pathways in regulation of dopaminergic differentiation and proliferation of stem cells, particularly Wnt/beta-catenin signaling in stimulating formation of the dopaminergic phenotype, Notch signaling in inhibiting stem cell differentiation, and Sonic hedgehog functioning in neural stem cell proliferation and neuronal cell production. Activation of oncogenes involved in uncontrolled proliferation or tumorigenicity of stem cells is also discussed. It is proposed that a selective molecular manipulation targeting strategy will greatly benefit cell replacement therapy for PD by effectively promoting dopaminergic neuronal cell generation and reducing risk of tumorigenicity of in vivo stem cell applications.

  16. c-Myc is a novel target of cell cycle arrest by honokiol in prostate cancer cells.

    Science.gov (United States)

    Hahm, Eun-Ryeong; Singh, Krishna Beer; Singh, Shivendra V

    2016-09-01

    Honokiol (HNK), a highly promising phytochemical derived from Magnolia officinalis plant, exhibits in vitro and in vivo anticancer activity against prostate cancer but the underlying mechanism is not fully clear. This study was undertaken to delineate the role of c-Myc in anticancer effects of HNK. Exposure of prostate cancer cells to plasma achievable doses of HNK resulted in a marked decrease in levels of total and/or phosphorylated c-Myc protein as well as its mRNA expression. We also observed suppression of c-Myc protein in PC-3 xenografts upon oral HNK administration. Stable overexpression of c-Myc in PC-3 and 22Rv1 cells conferred significant protection against HNK-mediated growth inhibition and G0-G1 phase cell cycle arrest. HNK treatment decreased expression of c-Myc downstream targets including Cyclin D1 and Enhancer of Zeste Homolog 2 (EZH2), and these effects were partially restored upon c-Myc overexpression. In addition, PC-3 and DU145 cells with stable knockdown of EZH2 were relatively more sensitive to growth inhibition by HNK compared with control cells. Finally, androgen receptor overexpression abrogated HNK-mediated downregulation of c-Myc and its targets particularly EZH2. The present study indicates that c-Myc, which is often overexpressed in early and late stages of human prostate cancer, is a novel target of prostate cancer growth inhibition by HNK.

  17. Up-regulation of hexokinaseII in myeloma cells: targeting myeloma cells with 3-bromopyruvate.

    Science.gov (United States)

    Nakano, Ayako; Miki, Hirokazu; Nakamura, Shingen; Harada, Takeshi; Oda, Asuka; Amou, Hiroe; Fujii, Shiro; Kagawa, Kumiko; Takeuchi, Kyoko; Ozaki, Shuji; Matsumoto, Toshio; Abe, Masahiro

    2012-02-01

    Hexokinase II (HKII), a key enzyme of glycolysis, is widely over-expressed in cancer cells. However, HKII levels and its roles in ATP production and ATP-dependent cellular process have not been well studied in hematopoietic malignant cells including multiple myeloma (MM) cells.We demonstrate herein that HKII is constitutively over-expressed in MM cells. 3-bromopyruvate (3BrPA), an inhibitor of HKII, promptly and substantially suppresses ATP production and induces cell death in MM cells. Interestingly, cocultures with osteoclasts (OCs) but not bone marrow stromal cells (BMSCs) enhanced the phosphorylation of Akt along with an increase in HKII levels and lactate production in MM cells. The enhancement of HKII levels and lactate production in MM cells by OCs were mostly abrogated by the PI3K inhibitor LY294002, suggesting activation of glycolysis in MM cells by OCs via the PI3K-Akt-HKII pathway. Although BMSCs and OCs stimulate MM cell growth and survival, 3BrPA induces cell death in MM cells even in cocultures with OCs as well as BMSCs. Furthermore, 3BrPA was able to diminish ATP-dependent ABC transporter activity to restore drug retention in MM cells in the presence of OCs. These results may underpin possible clinical application of 3BrPA in patients with MM.

  18. miR-29a modulates neuronal differentiation through targeting REST in mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Ping Duan

    Full Text Available OBJECTIVE: To investigate the modulation of microRNAs (miRNAs upon the neuronal differentiation of mesenchymal stem cells (MSCs through targeting RE-1 Silencing Factor (REST, a mature neuronal gene suppressor in neuronal and un-neuronal cells. METHODS: Rat bone marrow derived-MSCs were induced into neuron-like cells (MSC-NCs by DMSO and BHA in vitro. The expression of neuron specific enolase (NSE, microtubule-associated protein tau (Tau, REST and its target genes, including synaptosomal-associated protein 25 (SNAP25 and L1 cell adhesion molecular (L1CAM, were detected in MSCs and MSC-NCs. miRNA array analysis was conducted to screen for the upregulated miRNAs after neuronal differentiation. TargetScan was used to predict the relationship between these miRNAs and REST gene, and dual luciferase reporter assay was applied to validate it. Gain and loss of function experiments were used to study the role of miR-29a upon neuronal differentiation of MSCs. The knockdown of REST was conducted to show that miR-29a affected this process through targeting REST. RESULTS: MSCs were induced into neuron-like cells which presented neuronal cell shape and expressed NSE and Tau. The expression of REST declined and the expression of SNAP25 and L1CAM increased upon the neuronal differentiation of MSCs. Among 14 upregulated miRNAs, miR-29a was validated to target REST gene. During the neuronal differentiation of MSCs, miR-29a inhibition blocked the downregulation of REST, as well as the upregulation of SNAP25, L1CAM, NSE and Tau. REST knockdown rescued the effect of miR-29a inhibition on the expression of NSE and Tau. Meanwhile, miR-29a knockin significantly decreased the expression of REST and increased the expression of SNAP25 and L1CMA in MSCs, but did not significantly affect the expression of NSE and Tau. CONCLUSION: miR-29a regulates neurogenic markers through targeting REST in mesenchymal stem cells, which provides advances in neuronal differentiation research

  19. Targeting of the P2X7 receptor in pancreatic cancer and stellate cells.

    OpenAIRE

    Giannuzzo, Andrea; Saccomano, Mara; Napp, Joanna; Ellegaard, Maria; Alves, Frauke; Novak, Ivana

    2016-01-01

    The ATP-gated receptor P2X7 (P2X7R) is involved in regulation of cell survival and has been of interest in cancer field. Pancreatic ductal adenocarcinoma (PDAC) is a deadly cancer and new markers and therapeutic targets are needed. PDAC is characterized by a complex tumour microenvironment, which includes cancer and pancreatic stellate cells (PSCs), and potentially high nucleotide/side turnover. Our aim was to determine P2X7R expression and function in human pancreatic cancer cells in vitro a...

  20. Lipid-Based Nanovectors for