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Sample records for survival cellular proliferation

  1. Leukocytic promotion of prostate cellular proliferation.

    Science.gov (United States)

    McDowell, Kristy L; Begley, Lesa A; Mor-Vaknin, Nirit; Markovitz, David M; Macoska, Jill A

    2010-03-01

    Histological evidence of pervasive inflammatory infiltrate has been noted in both benign prostatic hyperplasia/hypertrophy (BPH) and prostate cancer (PCa). Cytokines known to attract particular leukocyte subsets are secreted from prostatic stroma consequent to aging and also from malignant prostate epithelium. Therefore, we hypothesized that leukocytes associated with either acute or chronic inflammation attracted to the prostate consequent to aging or tumorigenesis may promote the abnormal cellular proliferation associated with BPH and PCa. An in vitro system designed to mimic the human prostatic microenvironment incorporating prostatic stroma (primary and immortalized prostate stromal fibroblasts), epithelium (N15C6, BPH-1, LNCaP, and PC3 cells), and inflammatory infiltrate (HL-60 cells, HH, and Molt-3 T-lymphocytes) was developed. Modified Boyden chamber assays were used to test the ability of prostate stromal and epithelial cells to attract leukocytes and to test the effect of leukocytes on prostate cellular proliferation. Antibody arrays were used to identify leukocyte-secreted cytokines mediating prostate cellular proliferation. Leukocytic cells migrated towards both prostate stromal and epithelial cells. CD4+ T-lymphocytes promoted the proliferation of both transformed and non-transformed prostate epithelial cell lines tested, whereas CD8+ T-lymphocytes as well as dHL-60M macrophagic and dHL-60N neutrophilic cells selectively promoted the proliferation of PCa cells. The results of these studies show that inflammatory cells can be attracted to the prostate tissue microenvironment and can selectively promote the proliferation of non-transformed or transformed prostate epithelial cells, and are consistent with differential role(s) for inflammatory infiltrate in the etiologies of benign and malignant proliferative disease in the prostate. Prostate 70: 377-389, 2010. (c) 2009 Wiley-Liss, Inc.

  2. The kinetics of cellular proliferation in regenerating liver.

    Science.gov (United States)

    Fabrikant, J I

    1968-03-01

    The study concerns the kinetics of cellular proliferation in the different cell populations of the normal and regenerating rat liver. A detailed analysis is presented, which includes techniques of in vivo labeling of DNA with tritiated thymidine and high-resolution radioautography, of the temporal and spatial patterns of DNA synthesis and cell division in the parenchymal cells, littoral cells, bile duct epithelium, and other cellular components in the liver during the first 64 hr of regeneration after partial hepatectomy. The analysis of cell population kinetics indicates that (a) the rate of entry of parenchymal cells into synthesis, after an initial burst of proliferative activity, was an orderly progression at 3-4%/hr; (b) most cells divided once and a few twice, a large proportion of the cell deficit being replaced by 72 hr after the onset of proliferation; (c) T(s) was approximately 8.0 hr; T(gg2+m/2), 3.0 hr; and M, approximately 1.0 hr. Littoral cell proliferation began about 24 hr after the onset of parenchymal cell proliferation; the rate of entry of littoral cells into synthesis was greater than 4%/hr. Interlobular bile duct cell proliferation lagged well behind the parenchymal and littoral cell populations both in time and extent of proliferation.

  3. Stimulation of Cellular Proliferation by Hepatitis B Virus X Protein

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    Charles R. Madden

    2001-01-01

    Full Text Available Chronic infection with the hepatitis B virus (HBV is a known risk factor in the development of human hepatocellular carcinoma (HCC. The HBV-encoded X protein, HBx, has been investigated for properties that may explain its cancer cofactor role in transgenic mouse lines. We discuss here recent data showing that HBx is able to induce hepatocellular proliferation in vitro and in vivo. This property of HBx is predicted to sensitize hepatocytes to other HCC cofactors, including exposure to carcinogens and to other hepatitis viruses. Cellular proliferation is intimately linked to the mechanism(s by which most tumor-associated viruses transform virus-infected cells. The HBx alteration of the cell cycle provides an additional mechanism by which chronic HBV infection may contribute to HCC.

  4. Collagen Promotes Higher Adhesion, Survival and Proliferation of Mesenchymal Stem Cells.

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    Chinnapaka Somaiah

    Full Text Available Mesenchymal stem cells (MSC can differentiate into several cell types and are desirable candidates for cell therapy and tissue engineering. However, due to poor cell survival, proliferation and differentiation in the patient, the therapy outcomes have not been satisfactory. Although several studies have been done to understand the conditions that promote proliferation, differentiation and migration of MSC in vitro and in vivo, still there is no clear understanding on the effect of non-cellular bio molecules. Of the many factors that influence the cell behavior, the immediate cell microenvironment plays a major role. In this context, we studied the effect of extracellular matrix (ECM proteins in controlling cell survival, proliferation, migration and directed MSC differentiation. We found that collagen promoted cell proliferation, cell survival under stress and promoted high cell adhesion to the cell culture surface. Increased osteogenic differentiation accompanied by high active RHOA (Ras homology gene family member A levels was exhibited by MSC cultured on collagen. In conclusion, our study shows that collagen will be a suitable matrix for large scale production of MSC with high survival rate and to obtain high osteogenic differentiation for therapy.

  5. Learning and adult neurogenesis: survival with or without proliferation?

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    Prickaerts, Jos; Koopmans, Guido; Blokland, Arjan; Scheepens, Arjan

    2004-01-01

    Recent high quality papers have renewed interest in the phenomenon of neurogenesis within the adult mammalian brain. Many studies now show that neurogenesis can be modulated by environmental factors including physical activity, stress, and learning. These findings have considerable implications for neuroscience in general, including the study of learning and memory, neural network plasticity, aging, neurodegeneration, and the recovery from brain injury. Although new light has been shed on this field, many contradictory findings have been reported. Here we propose two principle issues which underlie these inconsistencies, with particular focus on the interaction between learning and neurogenesis. The first issue relates to the basic methodology of measuring the generation of new brain cells, i.e., proliferation, as compared to survival of the newly made cells. Mostly, measures of neurogenesis reported are a combination of proliferation and survival, making it impossible to distinguish between these separate processes. The second aspect is in regards to the role of environmental factors which can affect both proliferation and survival independently. Especially the interaction between stress and learning is of importance since these might counteract each other in some circumstances. Reviewing the literature while taking these issues into account indicates that, in contrast to some findings, cell proliferation in the dentate gyrus of the hippocampus as a result of learning cannot be ruled out yet. On the other hand, increased survival of granule cells in the dentate gyrus as a result of hippocampal-dependent learning has been clearly demonstrated. Moreover, this learning-induced survival of granule cells, which were born before the actual learning experience, might provide a molecular mechanism for the 'use it or lose it' principle.

  6. Inositol hexaphosphate (IP6) inhibits cellular proliferation in melanoma.

    Science.gov (United States)

    Rizvi, Irfan; Riggs, Dale R; Jackson, Barbara J; Ng, Alex; Cunningham, Cynthia; McFadden, David W

    2006-06-01

    Inositol Hexaphosphate (IP6) is a naturally occurring polyphosphorylated carbohydrate found in food sources high in fiber content. We have previously reported IP6 to have significant inhibitory effects against pancreatic cancer in vitro. We hypothesized that the IP6 would significantly inhibit cell growth of cutaneous melanoma in vitro. The melanoma line HTB68 was cultured using standard techniques and treated with IP6 at doses ranging from 0.2 to 1.0 mM/well. Cell viability was measured by MTT at 72 h. VEGF production was measured in the cell supernatants by ELISA. Apoptosis was evaluated by Annexin V-FITC and results calculated using FACS analysis. Statistical analysis was performed by ANOVA. Significant reductions (P < 0.001) in cellular proliferation were observed with IP6. Overall, IP6 exhibited a mean inhibition of cell growth of 52.1 +/- 11.5% (range, 1.6-83.0%) at 72 h of incubation. VEGF production was significantly reduced (P < 0.001) by the addition of IP6 (7.5 pg/ml) compared to control (40.9 pg/ml). IP6 significantly increased (P = 0.029) late apoptosis from 5.3 to 7.0% gated events. No changes in necrosis or early apoptosis were observed. Adjuvant treatment of melanoma continues to challenge clinicians and patients. Our findings that IP6 significantly decreased cellular growth, VEGF production and increased late apoptosis in melanoma suggest its potential therapeutic value. Further in vivo studies are planned to evaluate safety and clinical utility of this agent.

  7. Identification of a proliferation signature related to survival in nodal peripheral T-cell lymphomas.

    Science.gov (United States)

    Cuadros, Marta; Dave, Sandeep S; Jaffe, Elaine S; Honrado, Emiliano; Milne, Roger; Alves, Javier; Rodríguez, Jose; Zajac, Magdalena; Benitez, Javier; Staudt, Louis M; Martinez-Delgado, Beatriz

    2007-08-01

    Nodal peripheral T-cell lymphomas (PTCLs) constitute a heterogeneous group of neoplasms, suggesting the existence of molecular differences contributing to their histologic and clinical variability. Initial expression profiling studies of T-cell lymphomas have been inconclusive in yielding clinically relevant insights. We applied DNA microarrays to gain insight into the molecular signatures associated with prognosis. We analyzed the expression profiles of 35 nodal PTCLs (23 PTCLs unspecified and 12 angioimmunoblastic) using two different microarray platforms, the cDNA microarray developed at the Spanish National Cancer Centre and an oligonucleotide microarray. We identified five clusters of genes, the expression of which varied significantly among the samples. Genes in these clusters seemed to be functionally related to different cellular processes such as proliferation, inflammatory response, and T-cell or B-cell lineages. Regardless of the microarray platform used, overexpression of genes in the proliferation signature was associated significantly with shorter survival of patients. This proliferation signature included genes commonly associated with the cell cycle, such as CCNA, CCNB, TOP2A, and PCNA. Moreover the PTCL proliferation signature showed a statistically significant inverse correlation with clusters of the inflammatory response (P < .0001), as well as with the percentage of CD68(+) cells. Our findings indicate that proliferation could be an important factor in evaluating nodal PTCL outcome and may help to define a more aggressive phenotype.

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

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    Nelson S. Yee

    2015-10-01

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

  9. Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe; Bayer, Monika L; Mackey, Abigail

    2010-01-01

    PURPOSE: The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67. PROCEDURES: Wistar rats (......-derived results were supported by a correlation in calf muscle to Ki67 (protein and mRNA level), while this coherence was not found in tendon. CONCLUSION: FLT-PET seems to be a promising tool for imaging of exercise-induced cellular proliferation in musculo-tendinous tissue....

  10. Cellular Morphology-Mediated Proliferation and Drug Sensitivity of Breast Cancer Cells

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    Ryota Domura

    2017-06-01

    Full Text Available The interpretation of the local microenvironment of the extracellular matrix for malignant tumor cells is in intimate relation with metastatic spread of cancer cells involving the associated issues of cellular proliferation and drug responsiveness. This study was aimed to assess the combination of both surface topographies (fiber alignments and different stiffness of the polymeric substrates (poly(l-lactic acid and poly(ε-caprolactone, PLLA and PCL, respectively as well as collagen substrates (coat and gel to elucidate the effect of the cellular morphology on cellular proliferation and drug sensitivities of two different types of breast cancer cells (MDA-MB-231 and MCF-7. The morphological spreading parameter (nucleus/cytoplasm area ratio induced by the anthropogenic substrates has correlated intimately with the cellular proliferation and the drug sensitivity the half maximal inhibitory concentration (IC50 of cancer cells. This study demonstrated the promising results of the parameter for the evaluation of cancer cell malignancy.

  11. A naringenin–tamoxifen combination impairs cell proliferation and survival of MCF-7 breast cancer cells

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    Hatkevich, Talia; Ramos, Joseph; Santos-Sanchez, Idalys; Patel, Yashomati M., E-mail: ympatel@uncg.edu

    2014-10-01

    Since over 60% of breast cancers are estrogen receptor positive (ER+), many therapies have targeted the ER. The ER is activated by both estrogen binding and phosphorylation. While anti-estrogen therapies, such as tamoxifen (Tam) have been successful they do not target the growth factor promoting phosphorylation of the ER. Other proliferation pathways such as the phosphatidylinositol-3 kinase, (PI3K) and the mitogen-activated protein kinase (MAPK) pathways are activated in breast cancer cells and are associated with poor prognosis. Thus targeting multiple cellular proliferation and survival pathways at the onset of treatment is critical for the development of more effective therapies. The grapefruit flavanone naringenin (Nar) is an inhibitor of both the PI3K and MAPK pathways. Previous studies examining either Nar or Tam used charcoal-stripped serum which removed estrogen as well as other factors. We wanted to use serum containing medium in order to retain all the potential inducers of cell proliferation so as not to exclude any targets of Nar. Here we show that a Nar–Tam combination is more effective than either Tam alone or Nar alone in MCF-7 breast cancer cells. We demonstrate that a Nar–Tam combination impaired cellular proliferation and viability to a greater extent than either component alone in MCF-7 cells. Furthermore, the use of a Nar–Tam combination requires lower concentrations of both compounds to achieve the same effects on proliferation and viability. Nar may function by inhibiting both PI3K and MAPK pathways as well as localizing ERα to the cytoplasm in MCF-7 cells. Our results demonstrate that a Nar–Tam combination induces apoptosis and impairs proliferation signaling to a greater extent than either compound alone. These studies provide critical information for understanding the molecular mechanisms involved in cell proliferation and apoptosis in breast cancer cells. - Highlights: • Nar–Tam impairs cell viability more effectively than

  12. Cellular proliferation and angiogenesis in nasal polyps of young adult and geriatric patients.

    Science.gov (United States)

    Shin, Jae Min; Byun, Jang Yul; Baek, Byoung Joon; Lee, Jae Yong

    2015-06-01

    Cellular proliferation and angiogenesis are associated with pathophysiology of nasal polyposis (NP). In a previous report, we showed that patient age is a predictive factor of surgical outcomes among patients with chronic rhinosinusitis and NP, and that geriatric patients exhibit better outcomes than pediatric and adult patients. We postulated that better outcomes in the geriatric population may be secondary to decreased proliferation and angiogenesis within polyps. Therefore, we evaluated the cellular proliferation and angiogenesis in young adult and geriatric patients with NP. This was a prospective case-control study. Twenty patients were divided into 2 groups according to age (20 to 30 years vs ≥65 years of age). NP tissues were sampled during endoscopic sinus surgery and processed for immunohistochemistry. Cellular proliferation was evaluated with proliferating cell nuclear antigen and Ki67, and angiogenesis was assessed with vascular endothelial growth factor. We also compared objective surgical outcomes using endoscopy scores. Immunohistochemical analysis revealed significantly higher expression and positive reactivity of proliferating cell nuclear antigen and Ki67 in the polyps of young adults than in those of geriatric patients, whereas the expression of vascular endothelial growth factor was similar between the 2 groups. Endoscopy scores were better in the geriatric group. Geriatric patients have a lower cellular proliferative ability than young adults, and angiogenesis does not significantly differ between the 2 age groups. Cellular proliferation seems to be the cause of the different surgical outcomes between the 2 age groups, whereas angiogenesis has no significant influence on the postoperative course. © 2015 ARS-AAOA, LLC.

  13. Lipotoxicity in the Pancreatic Beta Cell: Not Just Survival and Function, but Proliferation as Well?

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    Sharma, Rohit B.; Alonso, Laura C.

    2014-01-01

    Free fatty acids (FFAs) exert both positive and negative effects on beta cell survival and insulin secretory function, depending on concentration, duration, and glucose abundance. Lipid signals are mediated not only through metabolic pathways, but also through cell surface and nuclear receptors. Toxicity is modulated by positive signals arising from circulating factors such as hormones, growth factors and incretins, as well as negative signals such as inflammatory mediators and cytokines. Intracellular mechanisms of lipotoxicity include metabolic interference and cellular stress responses such as oxidative stress, endoplasmic reticulum (ER) stress, and possibly autophagy. New findings strengthen an old hypothesis that lipids may also impair compensatory beta cell proliferation. Clinical observations continue to support a role for lipid biology in the risk and progression of both type 1 (T1D) and type 2 diabetes (T2D). This review summarizes recent work in this important, rapidly evolving field. PMID:24740729

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

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    Samarzija, Ivana [Ecole Polytechnique Federale Lausanne (EPFL), Department of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), 1015 Lausanne (Switzerland); Beard, Peter, E-mail: peter.beard@epfl.ch [Ecole Polytechnique Federale Lausanne (EPFL), Department of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), 1015 Lausanne (Switzerland)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer Unknown cellular mutations complement papillomavirus-induced carcinogenesis. Black-Right-Pointing-Pointer Hedgehog pathway components are expressed by cervical cancer cells. Black-Right-Pointing-Pointer Hedgehog pathway activators and inhibitors regulate cervical cancer cell biology. Black-Right-Pointing-Pointer Cell immortalization by papillomavirus and activation of Hedgehog are independent. -- Abstract: Human papillomavirus (HPV) infection is considered to be a primary hit that causes cervical cancer. However, infection with this agent, although needed, is not sufficient for a cancer to develop. Additional cellular changes are required to complement the action of HPV, but the precise nature of these changes is not clear. Here, we studied the function of the Hedgehog (Hh) signaling pathway in cervical cancer. The Hh pathway can have a role in a number of cancers, including those of liver, lung and digestive tract. We found that components of the Hh pathway are expressed in several cervical cancer cell lines, indicating that there could exists an autocrine Hh signaling loop in these cells. Inhibition of Hh signaling reduces proliferation and survival of the cervical cancer cells and induces their apoptosis as seen by the up-regulation of the pro-apoptotic protein cleaved caspase 3. Our results indicate that Hh signaling is not induced directly by HPV-encoded proteins but rather that Hh-activating mutations are selected in cells initially immortalized by HPV. Sonic Hedgehog (Shh) ligand induces proliferation and promotes migration of the cervical cancer cells studied. Together, these results indicate pro-survival and protective roles of an activated Hh signaling pathway in cervical cancer-derived cells, and suggest that inhibition of this pathway may be a therapeutic option in fighting cervical cancer.

  15. Human Homolog of Drosophila Ariadne (HHARI) is a marker of cellular proliferation associated with nuclear bodies

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    Elmehdawi, Fatima; Wheway, Gabrielle; Szymanska, Katarzyna [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); Adams, Matthew [BioScreening Technology Group, Biomedical Health Research Center, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); High, Alec S. [Department of Histopathology, Bexley Wing, St. James' s University Hospital, Beckett Street, Leeds, LS9 7TF West Yorkshire (United Kingdom); Johnson, Colin A., E-mail: c.johnson@leeds.ac.uk [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); Robinson, Philip A. [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom)

    2013-02-01

    HHARI (also known as ARIH1) is an ubiquitin-protein ligase and is the cognate of the E2, UbcH7 (UBE2L3). To establish a functional role for HHARI in cellular proliferation processes, we performed a reverse genetics screen that identified n=86/522 (16.5%) ubiquitin conjugation components that have a statistically significant effect on cell proliferation, which included HHARI as a strong hit. We then produced and validated a panel of specific antibodies that establish HHARI as both a nuclear and cytoplasmic protein that is expressed in all cell types studied. HHARI was expressed at higher levels in nuclei, and co-localized with nuclear bodies including Cajal bodies (p80 coilin, NOPP140), PML and SC35 bodies. We confirmed reduced cellular proliferation after ARIH1 knockdown with individual siRNA duplexes, in addition to significantly increased levels of apoptosis, an increased proportion of cells in G2 phase of the cell cycle, and significant reductions in total cellular RNA levels. In head and neck squamous cell carcinoma biopsies, there are higher levels of HHARI expression associated with increased levels of proliferation, compared to healthy control tissues. We demonstrate that HHARI is associated with cellular proliferation, which may be mediated through its interaction with UbcH7 and modification of proteins in nuclear bodies. -- Highlights: ► We produce and validate new antibody reagents for the ubiquitin-protein ligase HHARI. ► HHARI colocalizes with nuclear bodies including Cajal, PML and SC35 bodies. ► We establish new functions in cell proliferation regulation for HHARI. ► Increased HHARI expression associates with squamous cell carcinoma and proliferation.

  16. An Oncogenic Virus Promotes Cell Survival and Cellular Transformation by Suppressing Glycolysis.

    Directory of Open Access Journals (Sweden)

    Ying Zhu

    2016-05-01

    Full Text Available Aerobic glycolysis is essential for supporting the fast growth of a variety of cancers. However, its role in the survival of cancer cells under stress conditions is unclear. We have previously reported an efficient model of gammaherpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV-induced cellular transformation of rat primary mesenchymal stem cells. KSHV-transformed cells efficiently induce tumors in nude mice with pathological features reminiscent of Kaposi's sarcoma tumors. Here, we report that KSHV promotes cell survival and cellular transformation by suppressing aerobic glycolysis and oxidative phosphorylation under nutrient stress. Specifically, KSHV microRNAs and vFLIP suppress glycolysis by activating the NF-κB pathway to downregulate glucose transporters GLUT1 and GLUT3. While overexpression of the transporters rescues the glycolytic activity, it induces apoptosis and reduces colony formation efficiency in softagar under glucose deprivation. Mechanistically, GLUT1 and GLUT3 inhibit constitutive activation of the AKT and NF-κB pro-survival pathways. Strikingly, GLUT1 and GLUT3 are significantly downregulated in KSHV-infected cells in human KS tumors. Furthermore, we have detected reduced levels of aerobic glycolysis in several KSHV-infected primary effusion lymphoma cell lines compared to a Burkitt's lymphoma cell line BJAB, and KSHV infection of BJAB cells reduced aerobic glycolysis. These results reveal a novel mechanism by which an oncogenic virus regulates a key metabolic pathway to adapt to stress in tumor microenvironment, and illustrate the importance of fine-tuning the metabolic pathways for sustaining the proliferation and survival of cancer cells, particularly under stress conditions.

  17. Tetraspanin CD9 modulates human lymphoma cellular proliferation via histone deacetylase activity

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    Herr, Michael J. [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Surgery, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Longhurst, Celia M.; Baker, Benjamin [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Homayouni, Ramin [Department of Biology, Bioinformatics Program, University of Memphis, Memphis, TN 38152 (United States); Speich, Henry E.; Kotha, Jayaprakash [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Jennings, Lisa K., E-mail: ljennings@uthsc.edu [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Surgery, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Biology, Bioinformatics Program, University of Memphis, Memphis, TN 38152 (United States)

    2014-05-16

    Highlights: • CD9 is differentially expressed in human Burkitt’s lymphoma cells. • We found that CD9 expression promotes these cells proliferation. • CD9 expression also increases HDAC activity. • HDAC inhibition decreased both cell proliferation and importantly CD9 expression. • CD9 may dictate HDAC efficacy and play a role in HDAC regulation. - Abstract: Non-Hodgkin Lymphoma (NHL) is a type of hematological malignancy that affects two percent of the overall population in the United States. Tetraspanin CD9 is a cell surface protein that has been thoroughly demonstrated to be a molecular facilitator of cellular phenotype. CD9 expression varies in two human lymphoma cell lines, Raji and BJAB. In this report, we investigated the functional relationship between CD9 and cell proliferation regulated by histone deacetylase (HDAC) activity in these two cell lines. Introduction of CD9 expression in Raji cells resulted in significantly increased cell proliferation and HDAC activity compared to Mock transfected Raji cells. The increase in CD9–Raji cell proliferation was significantly inhibited by HDAC inhibitor (HDACi) treatment. Pretreatment of BJAB cells with HDAC inhibitors resulted in a significant decrease in endogenous CD9 mRNA and cell surface expression. BJAB cells also displayed decreased cell proliferation after HDACi treatment. These results suggest a significant relationship between CD9 expression and cell proliferation in human lymphoma cells that may be modulated by HDAC activity.

  18. Modeling cell adhesion and proliferation: a cellular-automata based approach.

    Science.gov (United States)

    Vivas, J; Garzón-Alvarado, D; Cerrolaza, M

    Cell adhesion is a process that involves the interaction between the cell membrane and another surface, either a cell or a substrate. Unlike experimental tests, computer models can simulate processes and study the result of experiments in a shorter time and lower costs. One of the tools used to simulate biological processes is the cellular automata, which is a dynamic system that is discrete both in space and time. This work describes a computer model based on cellular automata for the adhesion process and cell proliferation to predict the behavior of a cell population in suspension and adhered to a substrate. The values of the simulated system were obtained through experimental tests on fibroblast monolayer cultures. The results allow us to estimate the cells settling time in culture as well as the adhesion and proliferation time. The change in the cells morphology as the adhesion over the contact surface progress was also observed. The formation of the initial link between cell and the substrate of the adhesion was observed after 100 min where the cell on the substrate retains its spherical morphology during the simulation. The cellular automata model developed is, however, a simplified representation of the steps in the adhesion process and the subsequent proliferation. A combined framework of experimental and computational simulation based on cellular automata was proposed to represent the fibroblast adhesion on substrates and changes in a macro-scale observed in the cell during the adhesion process. The approach showed to be simple and efficient.

  19. Obesity and cancer: At the crossroads of cellular metabolism and proliferation

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    O’Rourke, Robert W.

    2014-01-01

    Obesity is associated with an increased risk of cancer. The mechanisms underlying this association include but are not limited to increased systemic inflammation, an anabolic hormonal milieu, and adipocyte-cancer crosstalk, aberrant stimuli that conspire to promote neoplastic transformation. Cellular proliferation is uncoupled from nutrient availability in malignant cells, promoting tumor progression. Elucidation of the mechanisms underlying the obesity-cancer connection will lead to the development of novel metabolism-based agents for cancer prevention and treatment. PMID:25264328

  20. Pulsed Electromagnetic Field Stimulates Cellular Proliferation in Human Intervertebral Disc Cells

    OpenAIRE

    Lee, Hwan-Mo; Kwon, Un-Hye; Kim, Hyang; Kim, Ho-Joong; Kim, Boram; Park, Jin-Oh; Moon, Eun-Soo; Moon, Seong-Hwan

    2010-01-01

    Purpose The purpose of this study is to investigate the mechanism of cellular proliferation of electromagnetic field (EMF) on human intervertebral disc (IVD) cells. Materials and Methods Human IVD cells were cultured three-dimensionally in alginate beads. EMF was exposed to IVD cells with 650?, 1.8 millitesla magnetic flux density, 60 Hz sinusoidal wave. Cultures were divided into a control and EMF group. Cytotoxicity, DNA synthesis and proteoglycan synthesis were measured by MTT assay, [3H]-...

  1. Cellular automata model for human articular chondrocytes migration, proliferation and cell death: An in vitro validation.

    Science.gov (United States)

    Vaca-González, J J; Gutiérrez, M L; Guevara, J M; Garzón-Alvarado, D A

    2017-01-01

    Articular cartilage is characterized by low cell density of only one cell type, chondrocytes, and has limited self-healing properties. When articular cartilage is affected by traumatic injuries, a therapeutic strategy such as autologous chondrocyte implantation is usually proposed for its treatment. This approach requires in vitro chondrocyte expansion to yield high cell number for cell transplantation. To improve the efficiency of this procedure, it is necessary to assess cell dynamics such as migration, proliferation and cell death during culture. Computational models such as cellular automata can be used to simulate cell dynamics in order to enhance the result of cell culture procedures. This methodology has been implemented for several cell types; however, an experimental validation is required for each one. For this reason, in this research a cellular automata model, based on random-walk theory, was devised in order to predict articular chondrocyte behavior in monolayer culture during cell expansion. Results demonstrated that the cellular automata model corresponded to cell dynamics and computed-accurate quantitative results. Moreover, it was possible to observe that cell dynamics depend on weighted probabilities derived from experimental data and cell behavior varies according to the cell culture period. Thus, depending on whether cells were just seeded or proliferated exponentially, culture time probabilities differed in percentages in the CA model. Furthermore, in the experimental assessment a decreased chondrocyte proliferation was observed along with increased passage number. This approach is expected to having other uses as in enhancing articular cartilage therapies based on tissue engineering and regenerative medicine.

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

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    Huang, Er-Wen [Guangzhou Institute of Forensic Science, Guangzhou (China); Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Xue, Sheng-Jiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Li, Xiao-Yan [Department of Pharmacy, The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China); Xu, Suo-Wen [Department of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou (China); Cheng, Jian-Ding; Zheng, Jin-Xiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong [Guangzhou Institute of Forensic Science, Guangzhou (China); Li, Jie, E-mail: mdlijie@sina.com [Department of Anaesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou (China); Liu, Chao, E-mail: liuchaogaj@21cn.com [Guangzhou Institute of Forensic Science, Guangzhou (China)

    2014-05-02

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

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

    Directory of Open Access Journals (Sweden)

    Hourinaz Behesti

    2013-01-01

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

  4. Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise: use of FLT and PET/CT

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe Charlotte; Bayer, Monika L; Mackey, Abigail L

    2010-01-01

    The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67....

  5. [Cell signaling pathways interaction in cellular proliferation: Potential target for therapeutic interventionism].

    Science.gov (United States)

    Valdespino-Gómez, Víctor Manuel; Valdespino-Castillo, Patricia Margarita; Valdespino-Castillo, Víctor Edmundo

    2015-01-01

    Nowadays, cellular physiology is best understood by analysing their interacting molecular components. Proteins are the major components of the cells. Different proteins are organised in the form of functional clusters, pathways or networks. These molecules are ordered in clusters of receptor molecules of extracellular signals, transducers, sensors and biological response effectors. The identification of these intracellular signaling pathways in different cellular types has required a long journey of experimental work. More than 300 intracellular signaling pathways have been identified in human cells. They participate in cell homeostasis processes for structural and functional maintenance. Some of them participate simultaneously or in a nearly-consecutive progression to generate a cellular phenotypic change. In this review, an analysis is performed on the main intracellular signaling pathways that take part in the cellular proliferation process, and the potential use of some components of these pathways as target for therapeutic interventionism are also underlined. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

  6. Effect of propolis on mitotic and cellular proliferation indices in human blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Montoro, A.; Almonacid, M.; Villaescusa, J. [Valencia Hospital Univ. la Fe, Servicio de Proteccion Radiologica (Spain); Barquinero, J. [Barcelona Univ. Autonom, Servicio de Dosimetria Biologica, Unidad de Antropologia, Dept. de Biologia Animal, Vegetal y Ecologia, barcelona (Spain); Barrios, L. [Barcelona Univ. Autonoma, Dept. de Biologia Celular y Fisiologia. Unidad de Biologia Celular (Spain); Verdu, G. [Valencia Univ. Politecnica, Dept. de Ingenieria Quimica y Nuclear (Spain); Perez, J. [Hospital la Fe, Seccion de Radiofisica, Servicio de Radioterapia, valencia (Spain)

    2006-07-01

    The study of the frequency of chromosomal aberrations per cell is the tool used in Biological dosimetry studies. Using dose-effect calibration curve obtained in our laboratory, we can evaluate the radioprotector effect of the EEP (ethanolic extract of propolis) in cultures in vitro. Propolis is the generic name for resinous substance collected by honeybees. The results showed a reduction in chromosomal aberrations's frequency of up to 50 %. The following study consisted of analyzing human peripheral blood lymphocytes exposed to 2 Gy {gamma} rays, in presence and absence of EEP, the change in the frequency of chromosome aberrations was analysed with biological dosimetry. The protection against the formation of dicentric and ring was dose-dependent, but there seemed to be a maximum protection, i.e. a further increase in the concentration of EEP does not show additional protection. This work studies the effect of the EEP of the cellular cycle using the mitotic and cellular proliferation index, as an alternative for the screening cytostatic activity. The results indicate that the lymphocytes which were cultures in presence of EEP exhibited a significant and dependent-concentration decrease in mitotic index and proliferation kinetics. The possible mechanisms involved in the radioprotective influence of EEP are discussed. (authors)

  7. Immunohistochemical expression of EGFR in oral leukoplakia: Association with clinicopathological features and cellular proliferation

    Science.gov (United States)

    Ribeiro, Daniela C.; Gleber-Netto, Frederico O.; Sousa, Sílvia F.; Bernardes, Vanessa F.; Guimarães-Abreu, Mauro H.N.

    2012-01-01

    Objectives: to investigate the immunoexpression of epidermal growth factor receptor (EGFR) in a sample of oral leukoplakias (OL) and to determine the receptor’s association with dysplasia, tobacco consumption, lesion site, and proliferation rate. Although EGFR should be overexpressed in some oral leukoplakias, the factors that may interfere with this expression and the influence of this receptor on epithelial proliferation have yet to be investigated. Study Design: Samples of oral leukoplakias (48) and of normal oral epithelium (10) were immunohistologically examined for expression of EGFR. Immunohistochemistry for Ki-67, and p27 were also performed in leukoplakias. EGFR expression was associated with clinical and pathological features. Results: EGFR was positive in 62.5% of the leukoplakias and 50% of normal oral epithelium. The number of EGFR positive OL located in high-risk sites was significantly higher than EGFR positive OL located in low-risk sites. Most of the p27 negative leukoplakias were EGFR positive, and the p27 index in the parabasal layer was diminished in the presence of dysplasia. Positivity for EGFR was not associated with dysplasia, tobacco exposure, or Ki-67. Conclusion: EGFR is expressed in leukoplakia regardless of dysplasia, but EGFR positivity should be more frequent in lesions sited in areas of high cancer risk. The association between EGFR and p27 may represent an important mechanism in the control of cellular proliferation and malignant progression of oral epithelium and therefore warrants further investigation. Key words:Oral leukoplakia, EGFR, p27, Ki-67, epithelial dysplasia. PMID:22322523

  8. Rhythmic expressed clock regulates the transcription of proliferating cellular nuclear antigen in teleost retina.

    Science.gov (United States)

    Song, Hang; Wang, Defeng; De Jesus Perez, Felipe; Xie, Rongrong; Liu, Zhipeng; Chen, Chun-Chun; Yu, Meijuan; Yuan, Liudi; Fernald, Russell D; Zhao, Sheng

    2017-07-01

    Teleost fish continues to grow their eyes throughout life with the body size. In Astatotilapia burtoni, the fish retina increases by adding new retinal cells at the ciliary marginal zone (CMZ) and in the outer nuclear layer (ONL). Cell proliferation at both sites exhibits a daily rhythm in number of dividing cells. To understand how this diurnal rhythm of new cell production is controlled in retinal progenitor cells, we studied the transcription pattern of clock genes in retina, including clock1a, clock1b, bmal1a (brain and muscle ARNT-Like), and per1b (period1b). We found that these genes have a strong diurnal rhythmic transcription during light-dark cycles but not in constant darkness. An oscillation in pcna transcription was also observed during light-dark cycles, but again not in constant darkness. Our results also indicate an association between Clock proteins and the upstream region of pcna (proliferating cellular nuclear antigen) gene. A luciferase reporter assay conducted in an inducible clock knockdown cell line further demonstrated that the mutation on predicted E-Boxes in pcna promoter region significantly attenuated the transcriptional activation induced by Clock protein. These results suggested that the diurnal rhythmic expression of clock genes in A. burtoni retina could be light dependent and might contribute to the daily regulation of the proliferation of the retina progenitors through key components of cell cycle machinery, for instance, pcna. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Pulsed electromagnetic field stimulates cellular proliferation in human intervertebral disc cells.

    Science.gov (United States)

    Lee, Hwan-Mo; Kwon, Un-Hye; Kim, Hyang; Kim, Ho-Joong; Kim, Boram; Park, Jin-Oh; Moon, Eun-Soo; Moon, Seong-Hwan

    2010-11-01

    The purpose of this study is to investigate the mechanism of cellular proliferation of electromagnetic field (EMF) on human intervertebral disc (IVD) cells. Human IVD cells were cultured three-dimensionally in alginate beads. EMF was exposed to IVD cells with 650 Ω, 1.8 millitesla magnetic flux density, 60 Hz sinusoidal wave. Cultures were divided into a control and EMF group. Cytotoxicity, DNA synthesis and proteoglycan synthesis were measured by MTT assay, [(3)H]-thymidine, and [(35)S]-sulfate incorporation. To detect phenotypical expression, reverse transcription-polymerase chain reactions (RT-PCR) were performed for aggrecan, collagen type I, and type II mRNA expression. To assess action mechanism of EMF, IVD cells were exposed to EMF with N(G)-Monomethyl-L-arginine (NMMA) and acetylsalicylic acid (ASA). There was no cytotoxicity in IVD cells with the EMF group in MTT assay. Cellular proliferation was observed in the EMF group (p EMF group and the control. Cultures with EMF showed no significant change in the expression of aggrecan, type I, and type II collagen mRNA compared to the control group. Cultures with NMMA (blocker of nitric oxide) or ASA (blocker of prostaglandin E2) exposed to EMF demonstrated decreased DNA synthesis compared to control cultures without NMMA or ASA (p EMF stimulated DNA synthesis in human IVD cells while no significant effect on proteoglycan synthesis and chondrogenic phenotype expressions. DNA synthesis was partially mediated by nitric oxide and prostaglandin E2. EMF can be utilized to stimulate proliferation of IVD cells, which may provide efficient cell amplification in cell therapy to degenerative disc disease.

  10. A study of the effect of salicylic acetic acid on a lymphocyte cell model of cellular activation and proliferation.

    Science.gov (United States)

    Aguilar, Enrique Aranda; de la Haba-Rodríguez, Juan; Macho, Antonio; Lucena, Concha; Gómez, Auxiliadora; Calzado, Marco; Muñoz, Eduardo

    2006-01-18

    Salicylic acetic acid (SAA) is a drug that has formed part of the treatment of many diseases for many years. Its anti-inflammatory activity is well known, but recently its possible role in the interference in the oncogenesis mechanisms has become apparent. With the aim of supporting these yet preliminary observations, we studied the effect of salicylic acetic acid on a cellular activation and proliferation model. We used lymphocytes obtained from peripheral blood, which were later exposed to cellular activation and proliferation stimulus by the SEB antigen. Lymphocyte activation was determined by direct immunoflourescence through expression of the receptor IL-2 (CD25) alpha chain and proliferation through the incorporation of tritiated thymidine to the DNA in synthesis together with the determination of the cellular cycle by flow cytometry. We found that both processes, activation and proliferation, are inhibited by increasing doses of SAA.

  11. Asiatic Acid Prevents the Deleterious Effects of Valproic Acid on Cognition and Hippocampal Cell Proliferation and Survival

    Directory of Open Access Journals (Sweden)

    Jariya Umka Welbat

    2016-05-01

    Full Text Available Valproic acid (VPA is commonly prescribed as an anticonvulsant and mood stabilizer used in the treatment of epilepsy and bipolar disorder. A recent study has demonstrated that VPA reduces histone deacetylase (HDAC activity, an action which is believed to contribute to the effects of VPA on neural stem cell proliferation and differentiation which may explain the cognitive impairments produced in rodents and patients. Asiatic acid is a triterpenoid derived from the medicinal plant Centella asiatica. Our previous study has shown that Asiatic acid improves working spatial memory and increases cell proliferation in the sub granular zone of the hippocampal dentate gyrus. In the present study we investigate the effects of Asiatic acid in preventing the memory and cellular effects of VPA. Male Spraque-Dawley rats were orally administered Asiatic acid (30 mg/kg/day for 28 days, while VPA-treated animals received injections of VPA (300 mg/kg twice a day from Day 15 to Day 28 for 14 days. Spatial memory was determined using the novel object location (NOL test and hippocampal cell proliferation and survival was quantified by immuostaining for Ki-67 and Bromodeoxyuridine (BrdU, respectively. The results showed that VPA-treated animals were unable to discriminate between objects in familiar and novel locations. Moreover, VPA significantly reduced numbers of Ki-67 and BrdU positive cells. These results indicate that VPA treatment caused impairments of spatial working memory, cell proliferation and survival in the subgranular zone (SGZ of the hippocampal dentate gyrus (DG. However, these abnormalities were restored to control levels by co-treatment with Asiatic acid. These data demonstrate that Asiatic acid could prevent the spatial memory and neurogenesis impairments caused by VPA.

  12. Distinct Effects of miR-210 Reduction on Neurogenesis: Increased Neuronal Survival of Inflammation But Reduced Proliferation Associated with Mitochondrial Enhancement.

    Science.gov (United States)

    Voloboueva, Ludmila A; Sun, Xiaoyun; Xu, Lijun; Ouyang, Yi-Bing; Giffard, Rona G

    2017-03-15

    Neurogenesis is essential to brain development and plays a central role in the response to brain injury. Stroke and head trauma stimulate proliferation of endogenous neural stem cells (NSCs); however, the survival of young neurons is sharply reduced by postinjury inflammation. Cellular mitochondria are critical to successful neurogenesis and are a major target of inflammatory injury. Mitochondrial protection was shown to improve survival of young neurons. This study tested whether reducing cellular microRNA-210 (miR-210) would enhance mitochondrial function and improve survival of young murine neurons under inflammatory conditions. Several studies have demonstrated the potential of miR-210 inhibition to enhance and protect mitochondrial function through upregulation of mitochondrial proteins. Here, miR-210 inhibition significantly increased neuronal survival and protected the activity of mitochondrial enzymes cytochrome c oxidase and aconitase in differentiating NSC cultures exposed to inflammatory mediators. Unexpectedly, we found that reducing miR-210 significantly attenuated NSC proliferation upon induction of differentiation. Further investigation revealed that increased mitochondrial function suppressed the shift to primarily glycolytic metabolism and reduced mitochondrial length characteristic of dividing cells. Activation of AMP-regulated protein kinase-retinoblastoma signaling is important in NSC proliferation and the reduction of this activation observed by miR-210 inhibition is one mechanism contributing to the reduced proliferation. Postinjury neurogenesis occurs as a burst of proliferation that peaks in days, followed by migration and differentiation over weeks. Our studies suggest that mitochondrial protective miR-210 inhibition should be delayed until after the initial burst of proliferation, but could be beneficial during the prolonged differentiation stage.SIGNIFICANCE STATEMENT Increasing the success of endogenous neurogenesis after brain injury

  13. Characterizing Tumors Using Metabolic Imaging: PET Imaging of Cellular Proliferation and Steroid Receptors

    Directory of Open Access Journals (Sweden)

    David A. Mankoff

    2000-01-01

    Full Text Available Treatment decisions in oncology are increasingly guided by information on the biologic characteristics of tumors. Currently, patient-specific information on tumor biology is obtained from the analysis of biopsy material. Positron emission tomography (PET provides quantitative estimates of regional biochemistry and receptor status and can overcome the sampling error and difficulty in performing serial studies inherent with biopsy. Imaging using the glucose metabolism tracer, 2-deoxy-2-fluoro-D-glucose (FDG, has demonstrated PET's ability to guide therapy in clinical oncology. In this review, we highlight PET approaches to imaging two other aspects of tumor biology: cellular proliferation and tumor steroid receptors. We review the biochemical and biologic processes underlying the imaging, positron-emitting radiopharmaceuticals that have been developed, quantitative image-analysis considerations, and clinical studies to date. This provides a basis for evaluating future developments in these promising applications of PET metabolic imaging.

  14. Structure and biochemical characterization of proliferating cellular nuclear antigen from a parasitic protozoon

    Energy Technology Data Exchange (ETDEWEB)

    Cardona-Felix, Cesar S.; Lara-Gonzalez, Samuel; Brieba, Luis G. (LNLS)

    2012-02-08

    Proliferating cellular nuclear antigen (PCNA) is a toroidal-shaped protein that is involved in cell-cycle control, DNA replication and DNA repair. Parasitic protozoa are early-diverged eukaryotes that are responsible for neglected diseases. In this work, a PCNA from a parasitic protozoon was identified, cloned and biochemically characterized and its crystal structure was determined. Structural and biochemical studies demonstrate that PCNA from Entamoeba histolytica assembles as a homotrimer that is able to interact with and stimulate the activity of a PCNA-interacting peptide-motif protein from E. histolytica, EhDNAligI. The data indicate a conservation of the biochemical mechanisms of PCNA-mediated interactions between metazoa, yeast and parasitic protozoa.

  15. Cellular proliferation markers in peripheral and central fibromas: a comparative study

    Directory of Open Access Journals (Sweden)

    Bruna Gonçalves Garcia

    2013-04-01

    Full Text Available Objective: To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. Material and Methods: Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF, in 4 cases of odontogenic fibroma (OdF, in 8 cases of peripheral ossifying fibroma (PEOF and 7 cases of ossifying fibroma (OsF. The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. Results: Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05. The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05. The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. Conclusions: The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions.

  16. Cellular proliferation markers in peripheral and central fibromas: a comparative study.

    Science.gov (United States)

    Garcia, Bruna Gonçalves; Caldeira, Patrícia Carlos; Johann, Aline Cristina Batista Rodrigues; Sousa, Suzana Cantanhede Orsini Machado de; Caliari, Marcelo Vidigal; Carmo, Maria Auxiliadora Vieira do; Mesquita, Ricardo Alves

    2013-01-01

    To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions.

  17. Cellular proliferation markers in peripheral and central fibromas: a comparative study

    Science.gov (United States)

    GARCIA, Bruna Gonçalves; CALDEIRA, Patrícia Carlos; JOHANN, Aline Cristina Batista Rodrigues; de SOUSA, Suzana Cantanhede Orsini Machado; CALIARI, Marcelo Vidigal; do CARMO, Maria Auxiliadora Vieira; MESQUITA, Ricardo Alves

    2013-01-01

    Objective: To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. Material and Methods: Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. Results: Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. Conclusions: The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions. PMID:23739858

  18. Inhibition of 2-nitropropane-induced cellular proliferation, DNA synthesis and histopathological changes by melatonin.

    Science.gov (United States)

    El-Sokkary, Gamal H

    2002-08-01

    2-Nitropropane (2-NP) is mutagenic in a number of short-term mutagenicity assays in vitro and in vivo, and is a potent hepatocarcinogen in rats. Many studies have determined that differences in the metabolism and disposition of the chemicals that produce mutagenicity were not responsible for their observed carcinogenic differences, but that carcinogenicity correlated with the ability of the respective isomer to induce cell proliferation in the target organ. Three groups of male rats (control, 2-NP-treated [4 mmol/kg] and 2-NP + melatonin [10 mg/kg]) were used in the current study. Cell proliferation was quantitated by incorporation of 3H-thymidine, detected by autoradiography, into newly synthesized DNA. Histopatholgical study was carried out to investigate the morphological changes. Twenty four hours after 2-NP administration, there was an increase in the labelling index (LI) and grain count per labelled nucleus (GC/N) in the hepatocytes of 2-NP-injected rats versus those of control animals. The increase was 69.5% in LI and 29.4% in GC/N. Melatonin treatment, 30 minutes preceding 2-NP, reduced the increase in LI (44.4%) and GC/N (20.7%) when compared with 2-NP-treated rats. Histopathology revealed multiple focal areas of necrosis in the liver following 2-NP injection. In the lung, there was a mucinous degeneration of the bronchial epithelium. Melatonin treatment restored the histopathological changes in both the liver and lung and they are more or less normal. Overall, these results seem to indicate that the stimulatory effect of 2-NP on the cellular proliferation and the rate of DNA synthesis in the liver may be one of mechanisms by which the carcinogen induces its carcinogenic action. Also, melatonin treatment strongly protects the studied organs against the toxic effect of 2-NP.

  19. Changes in cellular proliferation and plasma products are associated with liver failure

    Institute of Scientific and Technical Information of China (English)

    Juliana; Gil; Melga?o; Frederico; Marianetti; Soriani; Pedro; Henrique; Ferreira; Sucupira; Leonardo; Assaf; Pinheiro; Yasmine; Rangel; Vieira; Jaqueline; Mendes; de; Oliveira; Lia; Laura; Lewis-Ximenez; Cristina; Carvalho; Vianna; Araújo; Lúcio; Filgueiras; Pacheco-Moreira; Gustavo; Batista; Menezes; Oswaldo; Gon?alves; Cruz; Claudia; Lamarca; Vitral; Marcelo; Alves; Pinto

    2016-01-01

    AIM To study the differences in immune response and cytokine profile between acute liver failure and selflimited acute hepatitis.METHODS Forty-six patients with self-limited acute hepatitis(AH), sixteen patients with acute liver failure(ALF), and twenty-two healthy subjects were involved in this study. The inflammatory and anti-inflammatory products in plasma samples were quantified using commercial enzyme-linked immunoassays and quantitative real-time PCR. The cellular immune responses were measured by proliferation assay using flow cytometry. The groups were divided into viral- and non-viral-induced selflimited AH and ALF. Thus, we worked with five groups: Hepatitis A virus(HAV)-induced self-limited acute hepatitis(HAV-AH), HAV-induced ALF(HAV-ALF), nonviral-induced self-limited acute hepatitis(non-viral AH), non-viral-induced acute liver failure(non-viral ALF), and healthy subjects(HC). Comparisons among HAV and non-viral-induced AH and ALF were performed.RESULTS The levels of mitochondrial DNA(mt DNA) and the cytokines investigated [interleukin(IL)-6, IL-8, IL-10, interferon gamma, and tumor necrosis factor] were significantly increased in ALF patients, independently of etiology(P < 0.05). High plasma mt DNA and IL-10 were the best markers associated with ALF [mt DNA: OR = 320.5(95%CI: 14.42-7123.33), P < 0.0001; and IL-10: OR = 18.8(95%CI: 1.38-257.94), P = 0.028] and death (mt DNA: OR = 12.1(95%CI: 2.57-57.07), P = 0.002; and IL-10: OR = 8.01(95%CI: 1.26-50.97), P = 0.027)In the cellular proliferation assay, NKbright, NKT and regulatory T cells(TReg) predominated in virusspecific stimulation in HAV-induced ALF patients with an anergic behavior in the cellular response to mitotic stimulation. Therefore, in non-viral-induced ALF, anergic behavior of activated T cells was not observed after mitotic stimulation, as expected and as described by the literature. CONCLUSION mt DNA and IL-10 may be

  20. KPNA2 is overexpressed in human and mouse endometrial cancers and promotes cellular proliferation.

    Science.gov (United States)

    Ikenberg, Kristian; Valtcheva, Nadejda; Brandt, Simone; Zhong, Qing; Wong, Christine E; Noske, Aurelia; Rechsteiner, Markus; Rueschoff, Jan H; Caduff, Rosmarie; Dellas, Athanassios; Obermann, Ellen; Fink, Daniel; Fuchs, Thomas; Krek, Wilhelm; Moch, Holger; Frew, Ian J; Wild, Peter J

    2014-10-01

    Endometrial cancer is the most frequently occurring malignancy of the female genital tract in Western countries. Although in many cases surgically curable, about 30% of the tumours represent an aggressive and untreatable disease. In an attempt to establish a reliable prognostic marker for endometrial carcinomas disregarding their histological diversity, we investigated the expression of KPNA2, a mediator of nucleocytoplasmic transport, and other cell proliferation-associated proteins and their correlation with cancer progression. We analysed patient tissue microarrays (TMAs) assembled from 527 endometrial cancer tissue specimens and uterus samples from a Trp53 knockout mouse model of endometrial cancer. Our data show that KPNA2 expression was significantly up-regulated in human endometrial carcinomas and associated with higher tumour grade (p = 0.026), higher FIGO stage (p = 0.027), p53 overexpression (p endometrial cancer subtype was detected. In the mouse model, KPNA2 showed increased expression levels from precancerous (EmgD, EIC) to far-advanced invasive lesions. We further investigated the cell proliferation capacity after siRNA-mediated KPNA2 knockdown in the human endometrial cancer cell line MFE-296. KPNA2 silencing led to decreased proliferation of the cancer cells, suggesting interplay of the protein with the cell cycle. Taken together, increased expression of KPNA2 is an independent prognostic marker for poor survival. The mechanism of enhanced nucleocytoplasmic transport by KPNA2 overexpression seems a common event in aggressive cancers since we have shown a significant correlation of KPNA2 expression and tumour aggressiveness in a large variety of other solid tumour entities. Introducing KPNA2 immunohistochemistry in routine diagnostics may allow for the identification of patients who need more aggressive treatment regimens. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  1. Selenium-binding protein 1 may decrease gastric cellular proliferation and migration

    National Research Council Canada - National Science Library

    ZHANG, CHENJING; XU, WEN; PAN, WENSHENG; WANG, NANA; LI, GUOGANG; FAN, XIAOYUAN; XU, XIANG; SHEN, SHENGRONG; DAS, UNDURTI N

    2013-01-01

    .... Using cell proliferation assays, immunochemical staining and immunoblotting and flow cytometry methods and in a xenograft model, we evaluated the role of SBP1 in proliferation, migration, senescence...

  2. Effects of Thapsigargin on the Proliferation and Survival of Human Rheumatoid Arthritis Synovial Cells

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2014-01-01

    Full Text Available A series of experiments have been carried out to investigate the effects of different concentrations of thapsigargin (0, 0.001, 0.1, and 1 μM on the proliferation and survival of human rheumatoid arthritis synovial cells (MH7A. The results showed that thapsigargin can block the cell proliferation in human rheumatoid arthritis synovial cells in a time- and dose-dependent manner. Results of Hoechst staining suggested that thapsigargin may induce cell apoptosis in MH7A cells in a time- and dose-dependent manner, and the percentages of cell death reached 44.6% at thapsigargin concentration of 1 μM treated for 4 days compared to the control. The protein and mRNA levels of cyclin D1 decreased gradually with the increasing of thapsigargin concentration and treatment times. Moreover, the protein levels of mTORC1 downstream indicators pS6K and p4EBP-1 were reduced by thapsigargin treatment at different concentrations and times, which should be responsible for the reduced cyclin D1 expressions. Our results revealed that thapsigargin may effectively impair the cell proliferation and survival of MH7A cells. The present findings will help to understand the molecular mechanism of fibroblast-like synoviocytes proliferations and suggest that thapsigargin is of potential for the clinical treatment of rheumatoid arthritis.

  3. Spindle assembly checkpoint protein expression correlates with cellular proliferation and shorter time to recurrence in ovarian cancer.

    LENUS (Irish Health Repository)

    McGrogan, Barbara

    2014-07-01

    Ovarian carcinoma (OC) is the most lethal of the gynecological malignancies, often presenting at an advanced stage. Treatment is hampered by high levels of drug resistance. The taxanes are microtubule stabilizing agents, used as first-line agents in the treatment of OC that exert their apoptotic effects through the spindle assembly checkpoint. BUB1-related protein kinase (BUBR1) and mitotic arrest deficient 2 (MAD2), essential spindle assembly checkpoint components, play a key role in response to taxanes. BUBR1, MAD2, and Ki-67 were assessed on an OC tissue microarray platform representing 72 OC tumors of varying histologic subtypes. Sixty-one of these patients received paclitaxel and platinum agents combined; 11 received platinum alone. Overall survival was available for all 72 patients, whereas recurrence-free survival (RFS) was available for 66 patients. Increased BUBR1 expression was seen in serous carcinomas, compared with other histologies (P = .03). Increased BUBR1 was significantly associated with tumors of advanced stage (P = .05). Increased MAD2 and BUBR1 expression also correlated with increased cellular proliferation (P < .0002 and P = .02, respectively). Reduced MAD2 nuclear intensity was associated with a shorter RFS (P = .03), in ovarian tumors of differing histologic subtype (n = 66). In this subgroup, for those women who received paclitaxel and platinum agents combined (n = 57), reduced MAD2 intensity also identified women with a shorter RFS (P < .007). For the entire cohort of patients, irrespective of histologic subtype or treatment, MAD2 nuclear intensity retained independent significance in a multivariate model, with tumors showing reduced nuclear MAD2 intensity identifying patients with a poorer RFS (P = .05).

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-04-15

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

  5. Arecoline augments cellular proliferation in the prostate gland of male Wistar rats.

    Science.gov (United States)

    Saha, Indraneel; Chatterjee, Aniruddha; Mondal, Anushree; Maiti, Bishwa Ranjan; Chatterji, Urmi

    2011-09-01

    Areca nut chewing is the fourth most popular habit in the world due to its effects as a mild stimulant, causing a feeling of euphoria and slightly heightened alertness. Areca nuts contain several alkaloids and tannins, of which arecoline is the most abundant and known to have several adverse effects in humans, specially an increased risk of oral cancer. On evaluating the effects of arecoline on the male endocrine physiology in Wistar rats, it was found that arecoline treatment led to an overall enlargement and increase in the wet weight of the prostate gland, and a two-fold increase in serum gonadotropin and testosterone levels. Since the prostate is a major target for testosterone, the consequences of arecoline consumption were studied specifically in the prostate gland. Arecoline treatment led to an increase in the number of rough endoplasmic reticulum and reduction of secretory vesicles, signifying a hyperactive state of the prostate. Increased expression of androgen receptors in response to arecoline allowed for enhanced effect of testosterone in the prostate of treated animals, which augmented cell proliferation, subsequently confirmed by an increase in the expression of Ki-67 protein. Cellular proliferation was also the outcome of concomitant over expression of the G(1)-to-S cell cycle regulatory proteins, cyclin D1 and CDK4, both at the transcriptional and translational levels. Taken together, the findings provide the first evidence that regular use of arecoline may lead to prostatic hyperplasia and hypertrophy, and eventually to disorders associated with prostate enlargement. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Neuroprotective Effect of Uncaria rhynchophylla in Kainic Acid-Induced Epileptic Seizures by Modulating Hippocampal Mossy Fiber Sprouting, Neuron Survival, Astrocyte Proliferation, and S100B Expression

    Directory of Open Access Journals (Sweden)

    Chung-Hsiang Liu

    2012-01-01

    Full Text Available Uncaria rhynchophylla (UR, which is a traditional Chinese medicine, has anticonvulsive effect in our previous studies, and the cellular mechanisms behind this are still little known. Because of this, we wanted to determine the importance of the role of UR on kainic acid- (KA- induced epilepsy. Oral UR for 6 weeks can successfully attenuate the onset of epileptic seizure in animal tests. Hippocampal mossy fiber sprouting dramatically decreased, while neuronal survival increased with UR treatment in hippocampal CA1 and CA3 areas. Furthermore, oral UR for 6 weeks significantly attenuated the overexpression of astrocyte proliferation and S100B proteins but not γ-aminobutyric acid A (GABAA receptors. These results indicate that oral UR for 6 weeks can successfully attenuate mossy fiber sprouting, astrocyte proliferation, and S100B protein overexpression and increase neuronal survival in KA-induced epileptic rat hippocampus

  7. Abnormal expression of HAX-1 is associated with cellular proliferation and migration in human hypopharyngeal squamous cell carcinoma

    Science.gov (United States)

    Wu, Hao; Chen, Jianqiu; Wang, Qiang; Yin, Yong; Da, Peng; Le, Huijun; Zhang, Zhenxin; Qiu, Xiaoxia

    2017-01-01

    HCLS1-associated protein X-1 (HAX-1) is highly expressed or overexpressed in various types of human tumor, and its overexpression is associated with cancer metastasis and cellular proliferation. However, the precise molecular mechanism involved in HAX-1-associated proliferation and metastasis in hypopharyngeal carcinoma is unknown. The present study aimed to investigate the role of HAX-1 in the metastasis and proliferation of hypopharyngeal carcinoma. Reverse transcription-quantitative polymerase chain reaction analysis and western blotting indicated that HAX-1 was overexpressed in hypopharyngeal carcinoma specimens. MTT, clone formation and transwell assays were performed to detect the effects of HAX-1 knockdown or overexpression on the major oncogenic properties of the FaDu hypopharyngeal carcinoma cell line. Downregulation of HAX-1 was observed to significantly suppress cellular proliferation, migration and clonal. By contrast, overexpression of HAX-1 significantly promoted cellular proliferation, migration and clonal formation. Furthermore, HAX-1 knockdown markedly suppressed epithelial-mesenchymal transition. In conclusion, HAX-1 is a potential oncogene, and may promote the tumorigenesis and progression of hypopharyngeal carcinoma, as well as serve as a valuable molecular target for the treatment of hypopharyngeal carcinoma. PMID:28791389

  8. Stochastic cellular automata model of cell migration, proliferation and differentiation: validation with in vitro cultures of muscle satellite cells.

    Science.gov (United States)

    Garijo, N; Manzano, R; Osta, R; Perez, M A

    2012-12-07

    Cell migration and proliferation has been modelled in the literature as a process similar to diffusion. However, using diffusion models to simulate the proliferation and migration of cells tends to create a homogeneous distribution in the cell density that does not correlate to empirical observations. In fact, the mechanism of cell dispersal is not diffusion. Cells disperse by crawling or proliferation, or are transported in a moving fluid. The use of cellular automata, particle models or cell-based models can overcome this limitation. This paper presents a stochastic cellular automata model to simulate the proliferation, migration and differentiation of cells. These processes are considered as completely stochastic as well as discrete. The model developed was applied to predict the behaviour of in vitro cell cultures performed with adult muscle satellite cells. Moreover, non homogeneous distribution of cells has been observed inside the culture well and, using the above mentioned stochastic cellular automata model, we have been able to predict this heterogeneous cell distribution and compute accurate quantitative results. Differentiation was also incorporated into the computational simulation. The results predicted the myotube formation that typically occurs with adult muscle satellite cells. In conclusion, we have shown how a stochastic cellular automata model can be implemented and is capable of reproducing the in vitro behaviour of adult muscle satellite cells. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Centriole Amplification in Zebrafish Affects Proliferation and Survival but Not Differentiation of Neural Progenitor Cells

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    Edo Dzafic

    2015-10-01

    Full Text Available In animal cells, supernumerary centrosomes, resulting from centriole amplification, cause mitotic aberrations and have been associated with diseases, including microcephaly and cancer. To evaluate how centriole amplification impacts organismal development at the cellular and tissue levels, we used the in vivo imaging potential of the zebrafish. We demonstrate that centriole amplification can induce multipolar anaphase, resulting in binucleated cells. Such binucleation causes substantial apoptosis in the neuroepithelium. Interestingly, not all epithelia are similarly sensitive to binucleation, as skin cells tolerate it without entering apoptosis. In the neuroepithelium, however, binucleation leads to tissue degeneration and subsequent organismal death. Notably, this tissue degeneration can be efficiently counterbalanced by compensatory proliferation of wild-type cells. Because the risk for generating a binucleated daughter recurs at every cell division, centriole amplification in the neuroepithelium is especially deleterious during progenitor proliferation. Once cells reach the differentiation phase, however, centriole amplification does not impair neuronal differentiation.

  10. Telomerase activity is spontaneously increased in lymphocytes from patients with atopic dermatitis and correlates with cellular proliferation

    DEFF Research Database (Denmark)

    Wu, Kehuai; Volke, Anne Rehné; Lund, Marianne

    1999-01-01

    Telomerase is a ribonucleoprotein enzyme involved with cellular proliferation and cellular senescence. The aim of the present study was to investigate telomerase activity in lymphocytes from patients with atopic dermatitis (AD) and to observe its regulation of cellular proliferation. Peripheral......, and staphylococcal enterotoxin A (SEA) (0.1 microg/ml). Telomerase activity was measured by the telomeric repeat amplification protocol-based telomerase polymerase chain reaction enzyme-linked immunosorbent assay at 0 and 72 h of incubation. In addition, DNA synthesis of the cells was assayed using 3H......-thymidine incorporation. We found that telomerase activity in non-stimulated PBMC from patients with AD was significantly up-regulated without any stimulation during the 72 h of in vitro incubation. The most potent stimulator of telomerase activity was SEA, followed by anti-CD3 plus IL-2, anti-CD3 alone, and PPD. IL-2...

  11. A Flap Endonuclease (TcFEN1) Is Involved in Trypanosoma cruzi Cell Proliferation, DNA Repair, and Parasite Survival.

    Science.gov (United States)

    Ponce, Ivan; Aldunate, Carmen; Valenzuela, Lucia; Sepúlveda, Sofia; Garrido, Gilda; Kemmerling, Ulrike; Cabrera, Gonzalo; Galanti, Norbel

    2017-07-01

    FLAP endonucleases (FEN) are involved both in DNA replication and repair by processing DNA intermediaries presenting a nucleotide flap using its phosphodiesterase activity. In spite of these important functions in DNA metabolism, this enzyme was not yet studied in Trypanosomatids. Trypanosoma cruzi, the ethiological agent of Chagas disease, presents two dividing cellular forms (epimastigote and amastigote) and one non-proliferative, infective form (trypomastigote). The parasite survives DNA damage produced by reactive species generated in its hosts. The activity of a T. cruzi FLAP endonuclease (TcFEN1) was determined in the three cellular forms of the parasite using a DNA substrate generated by annealing three different oligonucleotides to form a double-stranded DNA with a 5' flap in the middle. This activity showed optimal pH and temperature similar to other known FENs. The substrate cut by the flap endonuclease activity could be ligated by the parasite generating a repaired DNA product. A DNA flap endonuclease coding sequence found in the T. cruzi genome (TcFEN1) was cloned, inserted in parasite expression vectors and transfected to epimastigotes. The purified native recombinant protein showed DNA flap endonuclease activity. This endonuclease was found located in the parasite nucleus of transfected epimastigotes and its over-expression increased both parasite proliferation and survival to H 2 O 2 . The presence of a flap endonuclease activity in T. cruzi and its nuclear location are indicative of the participation of this enzyme in DNA processing of flap fragments during DNA replication and repair in this parasite of ancient evolutive origin. J. Cell. Biochem. 118: 1722-1732, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. The Spalt transcription factors regulate cell proliferation, survival and epithelial integrity downstream of the Decapentaplegic signalling pathway

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    María F. Organista

    2012-10-01

    The expression of the spalt genes is regulated by the Decapentaplegic signalling pathway in the Drosophila wing. These genes participate in the patterning of the longitudinal wing veins by regulating the expression of vein-specific genes, and in the establishment of cellular affinities in the central region of the wing blade epithelium. The Spalt proteins act as transcription factors, most likely regulating gene expression by repression, but the identity of their target genes in the wing is still unknown. As a preliminary step to unravel the genetic hierarchy controlled by the Spalt proteins, we have analysed their requirements during wing development, and addressed to what extent they mediate all the functions of the Decapentaplegic pathway in this developmental system. We identify additional functions for Spalt in cell division, survival, and maintenance of epithelial integrity. Thus, Spalt activity is required to promote cell proliferation, acting in the G2/M transition of the cell cycle. The contribution of Spalt to cell division is limited to the central region of the wing blade, as they do not mediate the extra growth triggered by Decapentaplegic signalling in the peripheral regions of the wing disc. In addition, Spalt function is required to maintain cell viability in cells exposed to high levels of Decapentaplegic signalling. This aspect of Spalt function is related to the repression of JNK signalling in the spalt domain of expression. Finally, we further characterise the requirements of Spalt to maintain epithelial integrity by regulating cellular affinities between cells located in the central wing region. Our results indicate that Spalt function mediates most of the requirements identified for Decapentaplegic signalling, contributing to establish the cellular qualities that differentiate central versus peripheral territories in the wing blade.

  13. CSE1L/CAS, the cellular apoptosis susceptibility protein, enhances invasion and metastasis but not proliferation of cancer cells

    Directory of Open Access Journals (Sweden)

    Chen Ying-Chun

    2008-07-01

    Full Text Available Abstract Background The cellular apoptosis susceptibility (CAS protein is regarded as a proliferation-associated protein that associates with tumour proliferation as it associates with microtubule and functions in the mitotic spindle checkpoint. However, there is no any actual experimental study showing CAS (or CSE1 and CSE1L can increase the proliferation of cancer cells. Previous pathological study has reported that CAS was strongly positive stained in all of the metastasis melanoma that be examined. Thus, CAS may regulate the invasion and metastasis of cancers. CAS is highly expressed in cancers; if CAS is associated with cancer proliferation, then increased CAS expression should be able to increase the proliferation of cancer cells. We studied whether increased CAS expression can increase cancer cell proliferation and whether CAS regulates the invasion of cancer cells. Methods We enhanced or reduced CAS expression by transfecting CAS or anti-CAS expression vectors into human MCF-7 breast cancer cells. The proliferations of cells were determined by trypan blue exclusion assay and flow cytometry analysis. Invasion of cancer cells were determined by matrigel-based invasion assay. Results Our studies showed that increased CAS expression was unable to enhance cancer cell proliferation. Immunofluorescence showed CAS was distributed in cytoplasm areas near cell membrane and cell protrusions. CAS was localized in cytoplasmic vesicle and immunogold electronmicroscopy showed CAS was located in vesicle membrane. CAS overexpression enhanced matrix metalloproteinase-2 (MMP-2 secretion and cancer cell invasion. Animal experiments showed CAS reduction inhibited the metastasis of B16-F10 melanoma cells by 56% in C57BL/6 mice. Conclusion Our results indicate that CAS increases the invasion but not the proliferation of cancer cells. Thus, CAS plus ECM-degradation proteinases may be used as the markers for predicting the advance of tumour metastasis.

  14. MANF Is Indispensable for the Proliferation and Survival of Pancreatic β Cells

    Directory of Open Access Journals (Sweden)

    Maria Lindahl

    2014-04-01

    Full Text Available All forms of diabetes mellitus (DM are characterized by the loss of functional pancreatic β cell mass, leading to insufficient insulin secretion. Thus, identification of novel approaches to protect and restore β cells is essential for the development of DM therapies. Mesencephalic astrocyte-derived neurotrophic factor (MANF is an endoplasmic reticulum (ER-stress-inducible protein, but its physiological role in mammals has remained obscure. We generated MANF-deficient mice that strikingly develop severe diabetes due to progressive postnatal reduction of β cell mass, caused by decreased proliferation and increased apoptosis. Additionally, we show that lack of MANF in vivo in mouse leads to chronic unfolded protein response (UPR activation in pancreatic islets. Importantly, MANF protein enhanced β cell proliferation in vitro and overexpression of MANF in the pancreas of diabetic mice enhanced β cell regeneration. We demonstrate that MANF specifically promotes β cell proliferation and survival, thereby constituting a therapeutic candidate for β cell protection and regeneration.

  15. Distributing tasks via multiple input pathways increases cellular survival in stress.

    Science.gov (United States)

    Granados, Alejandro A; Crane, Matthew M; Montano-Gutierrez, Luis F; Tanaka, Reiko J; Voliotis, Margaritis; Swain, Peter S

    2017-05-17

    Improving in one aspect of a task can undermine performance in another, but how such opposing demands play out in single cells and impact on fitness is mostly unknown. Here we study budding yeast in dynamic environments of hyperosmotic stress and show how the corresponding signalling network increases cellular survival both by assigning the requirements of high response speed and high response accuracy to two separate input pathways and by having these pathways interact to converge on Hog1, a p38 MAP kinase. Cells with only the less accurate, reflex-like pathway are fitter in sudden stress, whereas cells with only the slow, more accurate pathway are fitter in increasing but fluctuating stress. Our results demonstrate that cellular signalling is vulnerable to trade-offs in performance, but that these trade-offs can be mitigated by assigning the opposing tasks to different signalling subnetworks. Such division of labour could function broadly within cellular signal transduction.

  16. Fisetin inhibits cellular proliferation and induces mitochondria-dependent apoptosis in human gastric cancer cells.

    Science.gov (United States)

    Sabarwal, Akash; Agarwal, Rajesh; Singh, Rana P

    2017-02-01

    The anticancer effects of fisetin, a dietary agent, are largely unknown against human gastric cancer. Herein, we investigated the mechanisms of fisetin-induced inhibition of growth and survival of human gastric carcinoma AGS and SNU-1 cells. Fisetin (25-100 μM) caused significant decrease in the levels of G1 phase cyclins and CDKs, and increased the levels of p53 and its S15 phosphorylation in gastric cancer cells. We also observed that growth suppression and death of non-neoplastic human intestinal FHs74int cells were minimally affected by fisetin. Fisetin strongly increased apoptotic cells and showed mitochondrial membrane depolarization in gastric cancer cells. DNA damage was observed as early as 3 h after fisetin treatment which was accompanied with gamma-H2A.X(S139) phosphorylation and cleavage of PARP. Fisetin-induced apoptosis was observed to be independent of p53. DCFDA and MitoSOX analyses showed an increase in mitochondrial ROS generation in time- and dose-dependent fashion. It also increased cellular nitrite and superoxide generation. Pre-treatment with N-acetyl cysteine (NAC) inhibited ROS generation and also caused protection from fisetin-induced DNA damage. The formation of comets were observed in only fisetin treated cells which was blocked by NAC pre-treatment. Further investigation of the source of ROS, using mitochondrial respiratory chain (MRC) complex inhibitors, suggested that fisetin caused ROS generation specifically through complex I. Collectively, these results for the first time demonstrated that fisetin possesses anticancer potential through ROS production most likely via MRC complex I leading to apoptosis in human gastric carcinoma cells. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. A Dual Program for Translation Regulation in Cellular Proliferation and Differentiation

    DEFF Research Database (Denmark)

    Gingold, Hila; Tehler, Disa; Christoffersen, Nanna R

    2014-01-01

    A dichotomous choice for metazoan cells is between proliferation and differentiation. Measuring tRNA pools in various cell types, we found two distinct subsets, one that is induced in proliferating cells, and repressed otherwise, and another with the opposite signature. Correspondingly, we found ...

  18. Sirtuin 7 promotes cellular survival following genomic stress by attenuation of DNA damage, SAPK activation and p53 response

    Energy Technology Data Exchange (ETDEWEB)

    Kiran, Shashi; Oddi, Vineesha [Laboratory of Cancer Biology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001 (India); Ramakrishna, Gayatri, E-mail: gayatrirama1@gmail.com [Laboratory of Cancer Biology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001 (India); Laboratory of Cancer Cell Biology, Department of Research, Institute of Liver and Biliary Sciences, Delhi 110070 (India)

    2015-02-01

    Maintaining the genomic integrity is a constant challenge in proliferating cells. Amongst various proteins involved in this process, Sirtuins play a key role in DNA damage repair mechanisms in yeast as well as mammals. In the present work we report the role of one of the least explored Sirtuin viz., SIRT7, under conditions of genomic stress when treated with doxorubicin. Knockdown of SIRT7 sensitized osteosarcoma (U2OS) cells to DNA damage induced cell death by doxorubicin. SIRT7 overexpression in NIH3T3 delayed cell cycle progression by causing delay in G1 to S transition. SIRT7 overexpressing cells when treated with low dose of doxorubicin (0.25 µM) showed delayed onset of senescence, lesser accumulation of DNA damage marker γH2AX and lowered levels of growth arrest markers viz., p53 and p21 when compared to doxorubicin treated control GFP expressing cells. Resistance to DNA damage following SIRT7 overexpression was also evident by EdU incorporation studies where cellular growth arrest was significantly delayed. When treated with higher dose of doxorubicin (>1 µM), SIRT7 conferred resistance to apoptosis by attenuating stress activated kinases (SAPK viz., p38 and JNK) and p53 response thereby shifting the cellular fate towards senescence. Interestingly, relocalization of SIRT7 from nucleolus to nucleoplasm together with its co-localization with SAPK was an important feature associated with DNA damage. SIRT7 mediated resistance to doxorubicin induced apoptosis and senescence was lost when p53 level was restored by nutlin treatment. Overall, we propose SIRT7 attenuates DNA damage, SAPK activation and p53 response thereby promoting cellular survival under conditions of genomic stress. - Highlights: • Knockdown of SIRT7 sensitized cells to DNA damage induced apoptosis. • SIRT7 delayed onset of premature senescence by attenuating DNA damage response. • Overexpression of SIRT7 delayed cell cycle progression by delaying G1/S transition. • Upon DNA damage SIRT

  19. Effects of 5-fluorouracil in nuclear and cellular morphology, proliferation, cell cycle, apoptosis, cytoskeletal and caveolar distribution in primary cultures of smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Marcelo de Carvalho Filgueiras

    Full Text Available Colon cancer is one of the most prevalent types of cancer in the world and is one of the leading causes of cancer death. The anti-metabolite 5- fluorouracil (5-FU is widely used in the treatment of patients with colon cancer and other cancer types. 5-FU-based chemotherapy has been shown to be very efficient in the improvement of overall survival of the patients and for the eradication of the disease. Unfortunately, common side effects of 5-FU include severe alterations in the motility of the gastrointestinal tissues. Nevertheless, the molecular and cellular effects of 5-FU in smooth muscle cells are poorly understood. Primary smooth muscle cell cultures are an important tool for studies of the biological consequences of 5-FU at the cellular level. The avian gizzard is one of the most robust organs of smooth muscle cells. Here we studied the molecular and cellular effects of the chemotherapic drug 5-FU in a primary culture of chick gizzard smooth muscle cells. We found that treatment of smooth muscle cells with 5-FU inhibits cell proliferation by the arrest of cells in the G1 phase of cell cycle and induce apoptosis. 5-FU induced a decrease in the percentage of histone H3-positive cells. Treatment of cells with 5-FU induced changes in cellular and nuclear morphology, a decrease in the number of stress fibers and a major decrease in the number of caveolin-3 positive cells. Our results suggest that the disorganization of the actin cytoskeleton and the reduction of caveolin-3 expression could explain the alterations in contractility observed in patients treated with 5-FU. These findings might have an impact in the understanding of the cellular effects of 5-FU in smooth muscle tissues and might help the improvement of new therapeutic protocols for the treatment of colon cancer.

  20. HPV16 E2 could act as down-regulator in cellular genes implicated in apoptosis, proliferation and cell differentiation

    Directory of Open Access Journals (Sweden)

    Valencia-Hernández Armando

    2011-05-01

    Full Text Available Abstract Background Human Papillomavirus (HPV E2 plays several important roles in the viral cycle, including the transcriptional regulation of the oncogenes E6 and E7, the regulation of the viral genome replication by its association with E1 helicase and participates in the viral genome segregation during mitosis by its association with the cellular protein Brd4. It has been shown that E2 protein can regulate negative or positively the activity of several cellular promoters, although the precise mechanism of this regulation is uncertain. In this work we constructed a recombinant adenoviral vector to overexpress HPV16 E2 and evaluated the global pattern of biological processes regulated by E2 using microarrays expression analysis. Results The gene expression profile was strongly modified in cells expressing HPV16 E2, finding 1048 down-regulated genes, and 581 up-regulated. The main cellular pathway modified was WNT since we found 28 genes down-regulated and 15 up-regulated. Interestingly, this pathway is a convergence point for regulating the expression of genes involved in several cellular processes, including apoptosis, proliferation and cell differentiation; MYCN, JAG1 and MAPK13 genes were selected to validate by RT-qPCR the microarray data as these genes in an altered level of expression, modify very important cellular processes. Additionally, we found that a large number of genes from pathways such as PDGF, angiogenesis and cytokines and chemokines mediated inflammation, were also modified in their expression. Conclusions Our results demonstrate that HPV16 E2 has regulatory effects on cellular gene expression in HPV negative cells, independent of the other HPV proteins, and the gene profile observed indicates that these effects could be mediated by interactions with cellular proteins. The cellular processes affected suggest that E2 expression leads to the cells in to a convenient environment for a replicative cycle of the virus.

  1. Melanoma-initiating cells exploit M2 macrophage TGFβ and arginase pathway for survival and proliferation

    Science.gov (United States)

    Tham, Muly; Tan, Kar Wai; Keeble, Jo; Wang, Xiaojie; Hubert, Sandra; Barron, Luke; Tan, Nguan Soon; Kato, Masashi; Prevost-Blondel, Armelle; Angeli, Veronique; Abastado, Jean-Pierre

    2014-01-01

    M2 macrophages promote tumor growth and metastasis, but their interactions with specific tumor cell populations are poorly characterized. Using a mouse model of spontaneous melanoma, we showed that CD34− but not CD34+ tumor-initiating cells (TICs) depend on M2 macrophages for survival and proliferation. Tumor-associated macrophages (TAMs) and macrophage-conditioned media protected CD34− TICs from chemotherapy in vitro. In vivo, while inhibition of CD115 suppressed the macrophage-dependent CD34− TIC population, chemotherapy accelerated its development. The ability of TICs to respond to TAMs was acquired during melanoma progression and immediately preceded a surge in metastatic outgrowth. TAM-derived transforming growth factor-β (TGFβ) and polyamines produced via the Arginase pathway were critical for stimulation of TICs and synergized to promote their growth. PMID:25294815

  2. G-CSFR ubiquitination critically regulates myeloid cell survival and proliferation.

    Directory of Open Access Journals (Sweden)

    Jing Ai

    Full Text Available The granulocyte colony-stimulating factor receptor (G-CSFR is a critical regulator of granulopoiesis. Mutations in the G-CSFR in patients with severe congenital neutropenia (SCN transforming to acute myelogenous leukemia (AML have been shown to induce hypersensitivity and enhanced growth responses to G-CSF. Recent studies have demonstrated the importance of the ubiquitin/proteasome system in the initiation of negative signaling by the G-CSFR. To further investigate the role of ubiquitination in regulating G-CSFR signaling, we generated a mutant form of the G-CSFR (K762R/G-CSFR which abrogates the attachment of ubiquitin to the lysine residue at position 762 of the G-CSFR that is deleted in the Delta716 G-CSFR form isolated from patients with SCN/AML. In response to G-CSF, mono-/polyubiquitination of the G-CSFR was impaired in cells expressing the mutant K762R/G-CSFR compared to cells transfected with the WT G-CSFR. Cells stably transfected with the K762R/G-CSFR displayed a higher proliferation rate, increased sensitivity to G-CSF, and enhanced survival following cytokine depletion, similar to previously published data with the Delta716 G-CSFR mutant. Activation of the signaling molecules Stat5 and Akt were also increased in K762R/G-CSFR transfected cells in response to G-CSF, and their activation remained prolonged after G-CSF withdrawal. These results indicate that ubiquitination is required for regulation of G-CSFR-mediated proliferation and cell survival. Mutations that disrupt G-CSFR ubiquitination at lysine 762 induce aberrant receptor signaling and hyperproliferative responses to G-CSF, which may contribute to leukemic transformation.

  3. High MRPS23 expression contributes to hepatocellular carcinoma proliferation and indicates poor survival outcomes.

    Science.gov (United States)

    Pu, Meng; Wang, Jianlin; Huang, Qike; Zhao, Ge; Xia, Congcong; Shang, Runze; Zhang, Zhuochao; Bian, Zhenyuan; Yang, Xishegn; Tao, Kaishan

    2017-07-01

    Hepatocellular carcinoma is one of the most prevalent neoplasms and the leading cause of cancer-related mortality worldwide. Mitochondrial ribosomal protein S23 is encoded by a nuclear gene and participates in mitochondrial protein translation. Mitochondrial ribosomal protein S23 overexpression has been found in many types of cancer. In this study, we explored mitochondrial ribosomal protein S23 expression in primary hepatocellular carcinoma tissues compared with matched adjacent non-tumoral liver tissues using mitochondrial ribosomal protein S23 messenger RNA and protein levels collected from public databases and clinical samples. Immunohistochemistry was performed to analyze the relationship between mitochondrial ribosomal protein S23 and various clinicopathological features. The results indicated that mitochondrial ribosomal protein S23 was significantly overexpressed in hepatocellular carcinoma. High mitochondrial ribosomal protein S23 expression was correlated with the tumor size and tumor-metastasis-node stage. Moreover, patients with high mitochondrial ribosomal protein S23 expression levels presented poorer survival rates. Mitochondrial ribosomal protein S23 was an independent prognostic factor for survival, especially at the early stage of hepatocellular carcinoma. In addition, the downregulation of mitochondrial ribosomal protein S23 decreased the proliferation of hepatocellular carcinoma in vitro and in vivo. In conclusion, we verified for the first time that mitochondrial ribosomal protein S23 expression was upregulated in hepatocellular carcinoma. High mitochondrial ribosomal protein S23 levels can predict poor clinical outcomes in hepatocellular carcinoma, and this protein plays a key role in tumor proliferation. Therefore, mitochondrial ribosomal protein S23 may be a potential therapeutic target for hepatocellular carcinoma.

  4. B-cell lymphoma 6 promotes proliferation and survival of trophoblastic cells.

    Science.gov (United States)

    Muschol-Steinmetz, Cornelia; Jasmer, Britta; Kreis, Nina-Naomi; Steinhäuser, Kerstin; Ritter, Andreas; Rolle, Udo; Yuan, Juping; Louwen, Frank

    2016-01-01

    Preeclampsia is one of the leading causes of maternal and perinatal mortality and morbidity and its pathogenesis is not fully understood. B-cell lymphoma 6 (BCL6), a key regulator of B-lymphocyte development, is altered in preeclamptic placentas. We show here that BCL6 is present in all 3 studied trophoblast cell lines and it is predominantly expressed in trophoblastic HTR-8/SVneo cells derived from a 1(st) trimester placenta, suggestive of its involvement in trophoblast expansion in the early stage of placental development. BCL6 is strongly stabilized upon stress stimulation. Inhibition of BCL6, by administrating either small interfering RNA or a specific small molecule inhibitor 79-6, reduces proliferation and induces apoptosis in trophoblastic cells. Intriguingly, depletion of BCL6 in HTR-8/SVneo cells results in a mitotic arrest associated with mitotic defects in centrosome integrity, indicative of its involvement in mitotic progression. Thus, like in haematopoietic cells and breast cancer cells, BCL6 promotes proliferation and facilitates survival of trophoblasts under stress situation. Further studies are required to decipher its molecular roles in differentiation, migration and the fusion process of trophoblasts. Whether increased BCL6 observed in preeclamptic placentas is one of the causes or the consequences of preeclampsia warrants further investigations in vivo and in vitro.

  5. Growth, survival, proliferation and pathogenesis of Listeria monocytogenes under low oxygen or anaerobic conditions: a review.

    Science.gov (United States)

    Lungu, B; Ricke, S C; Johnson, M G

    2009-01-01

    Listeria monocytogenes is a Gram positive facultative anaerobe that causes listeriosis, a disease that mainly affects the immune-compromised, the elderly, infants and pregnant women. In the susceptible immune challenged population, listeriosis is very severe and has a fatality rate of up to 30%. Control of L. monocytogenes is difficult due to its: 1) widespread presence in the environment, 2) intrinsic physiological resistance, 3) ability to adapt to external stresses and 4) ability to grow at a wide range of temperatures. L. monocytogenes encounters anaerobic conditions in the external environment as well as during pathogenesis. Although L. monocytogenes is a facultative anaerobe, the differential effects of O(2) and oxidation-reduction potential on the multiplication of L. monocytogenes have not been established. In addition, most laboratory studies to determine the growth, survival and persistence of this pathogen in foods as well as in the environment have emphasized the response of this pathogen under aerobic conditions. Consequently, this has led to a limited understanding of the metabolic and physiological responses of L. monocytogenes in low oxygen environments. Therefore, the objective of our review was to highlight the progress that has been made in L. monocytogenes research with emphasis on the role of low oxygen and/or anaerobiosis in the growth, survival and proliferation of this pathogen in the environment as well as during pathogenesis.

  6. Cellular Retinoic Acid-Binding Protein 1 Modulates Stem Cell Proliferation to Affect Learning and Memory in Male Mice.

    Science.gov (United States)

    Lin, Yu-Lung; Persaud, Shawna D; Nhieu, Jennifer; Wei, Li-Na

    2017-09-01

    Retinoic acid (RA) is the active ingredient of vitamin A. It exerts its canonical activity by binding to nuclear RA receptors (RARs) to regulate gene expression. Increasingly, RA is also known to elicit nongenomic RAR-independent activities, most widely detected in activating extracellular regulated kinase (ERK)1/2. This study validated the functional role of cellular retinoic acid-binding protein 1 (Crabp1) in mediating nongenomic activity in RA, specifically activating ERK1/2 to rapidly augment the cell cycle by expanding the growth 1 phase and slowing down embryonic stem cell and neural stem cell (NSC) proliferation. The study further uncovered the physiological activity of Crabp1 in modulating NSC proliferation and animal behavior. In the Crabp1 knockout mouse hippocampus, where Crabp1 is otherwise detected in the subgranular zone, neurogenesis and NSC proliferation increased and hippocampus-dependent brain functions such as learning and memory correspondingly improved. This study established the physiological role of Crabp1 in modulating stem cell proliferation and hippocampus-dependent brain activities such as learning and memory. Copyright © 2017 Endocrine Society.

  7. Evidence that thyroid hormone induces olfactory cellular proliferation in salmon during a sensitive period for imprinting.

    Science.gov (United States)

    Lema, Sean C; Nevitt, Gabrielle A

    2004-09-01

    Salmon have long been known to imprint and home to natal stream odors, yet the mechanisms driving olfactory imprinting remain obscure. The timing of imprinting is associated with elevations in plasma thyroid hormone levels, with possible effects on growth and proliferation of the peripheral olfactory system. Here, we begin to test this idea by determining whether experimentally elevated plasma levels of 3,5,3'-triiodothyronine (T(3)) influence cell proliferation as detected by the 5-bromo-2'-deoxyuridine (BrdU) cell birth-dating technique in the olfactory epithelium of juvenile coho salmon (Oncorhynchus kisutch). We also explore how natural fluctuations in thyroxine (T(4)) relate to proliferation in the epithelium during the parr-smolt transformation. In both studies, we found that BrdU labeled both single and clusters of mitotic cells. The total number of BrdU-labeled cells in the olfactory epithelium was significantly greater in fish with artificially elevated T(3) compared with placebo controls. This difference in proliferation was restricted to the basal region of the olfactory epithelium, where multipotent progenitor cells differentiate into olfactory receptor neurons. The distributions of mitotic cluster sizes differed significantly from a Poisson distribution for both T(3) and placebo treatments, suggesting that proliferation tends to be non-random. Over the course of the parr-smolt transformation, changes in the density of BrdU cells showed a positive relationship with natural fluctuations in plasma T(4). This relationship suggests that even small changes in thyroid activity can stimulate the proliferation of neural progenitor cells in the salmon epithelium. Taken together, our results establish a link between the thyroid hormone axis and measurable anatomical changes in the peripheral olfactory system.

  8. MiR-371-5p facilitates pancreatic cancer cell proliferation and decreases patient survival.

    Directory of Open Access Journals (Sweden)

    De He

    Full Text Available microRNAs (miRNAs play a critical role in tumorigenesis, either as a tumor suppressor or as an oncogenic miRNA, depending on different tumor types. To date, scientists have obtained a substantial amount of knowledge with regard to miRNAs in pancreatic cancer. However, the expression and function of miR-371-5p in pancreatic cancer has not been clearly elucidated. The aim of this study was to investigate the roles of miR-371-5p in pancreatic cancer and its association with the survival of patients with pancreatic cancer.The expression of miR-371-5p was examined in pancreatic duct adenocarcinoma (PDAC and their adjacent normal pancreatic tissues (ANPT or in pancreatic cancer cell lines by qRT-PCR. The association of miR-371-5p expression with overall survival was determined. The proliferation and apoptosis of SW-1990 and Panc-1 cells, transfected with miR-371-5p mimics or inhibitor, were assessed using MTT assay and flow cytometry, respectively. The tumorigenicity was evaluated via mice xenograft experiments. miR-371-5p promoter interactions were analyzed by chromatin immunoprecipitation assays (ChIP. Protein expression was analyzed by Western blot.The expression level of miR-371-5p was dramatically upregulated in clinical PDAC tissues compared with ANPT. Patients with high miR-371-5p expression had a significantly shorter survival than those with low miR-371-5p expression. The in vitro and in vivo assays showed that overexpression of miR-371-5p resulted in cell proliferation and increased tumor growth, which was associated with inhibitor of growth 1 (ING1 downregulation. Interestingly, we also found that ING1, in turn, inhibited expression of miR-371-5p in the promoter region.our study demonstrates a novel ING1-miR-371-5p regulatory feedback loop, which may have a critical role in PDAC. Thus miR-371-5p can prove to be a novel prognostic factor and therapeutic target for pancreatic cancer treatment.

  9. Epigenetic inactivation of TWIST2 in acute lymphoblastic leukemia modulates proliferation, cell survival and chemosensitivity

    Science.gov (United States)

    Thathia, Shabnam H.; Ferguson, Stuart; Gautrey, Hannah E.; van Otterdijk, Sanne D.; Hili, Michela; Rand, Vikki; Moorman, Anthony V.; Meyer, Stefan; Brown, Robert; Strathdee, Gordon

    2012-01-01

    Background Altered regulation of many transcription factors has been shown to be important in the development of leukemia. TWIST2 modulates the activity of a number of important transcription factors and is known to be a regulator of hematopoietic differentiation. Here, we investigated the significance of epigenetic regulation of TWIST2 in the control of cell growth and survival and in response to cytotoxic agents in acute lymphoblastic leukemia. Design and Methods TWIST2 promoter methylation status was assessed quantitatively, by combined bisulfite and restriction analysis (COBRA) and pyrosequencing assays, in multiple types of leukemia and TWIST2 expression was determined by quantitative reverse transcriptase polymerase chain reaction analysis. The functional role of TWIST2 in cell proliferation, survival and response to chemotherapy was assessed in transient and stable expression systems. Results We found that TWIST2 was inactivated in more than 50% of cases of childhood and adult acute lymphoblastic leukemia through promoter hypermethylation and that this epigenetic regulation was especially prevalent in RUNX1-ETV6-driven cases. Re-expression of TWIST2 in cell lines resulted in a dramatic reduction in cell growth and induction of apoptosis in the Reh cell line. Furthermore, re-expression of TWIST2 resulted in increased sensitivity to the chemotherapeutic agents etoposide, daunorubicin and dexamethasone and TWIST2 hypermethylation was almost invariably found in relapsed adult acute lymphoblastic leukemia (91% of samples hypermethylated). Conclusions This study suggests a dual role for epigenetic inactivation of TWIST2 in acute lymphoblastic leukemia, initially through altering cell growth and survival properties and subsequently by increasing resistance to chemotherapy. PMID:22058208

  10. Protein kinase CK2 and its role in cellular proliferation, development and pathology

    DEFF Research Database (Denmark)

    Guerra, B; Issinger, O G

    1999-01-01

    , signaling, proliferation and in various steps of development. The tetrameric holoenzyme (alpha2beta2) consists of two catalytic alpha-subunits and two regulatory beta-subunits. The structure of the catalytic subunit with the fixed positioning of the activation segment in the active conformation through its...

  11. Accumulated SET protein up-regulates and interacts with hnRNPK, increasing its binding to nucleic acids, the Bcl-xS repression, and cellular proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Luciana O.; Garcia, Cristiana B.; Matos-Silva, Flavia A. [Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil); Curti, Carlos [Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil); Leopoldino, Andréia M., E-mail: andreiaml@usp.br [Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil)

    2014-02-28

    Highlights: • hnRNPK is a new target of SET. • SET regulates hnRNPK. • SET and hnRNPK accumulation promotes tumorigenesis. • SET accumulation is a potential model to study genes regulated by SET-hnRNPK. - Abstract: SET and hnRNPK are proteins involved in gene expression and regulation of cellular signaling. We previously demonstrated that SET accumulates in head and neck squamous cell carcinoma (HNSCC); hnRNPK is a prognostic marker in cancer. Here, we postulate that SET and hnRNPK proteins interact to promote tumorigenesis. We performed studies in HEK293 and HNSCC (HN6, HN12, and HN13) cell lines with SET/hnRNPK overexpression and knockdown, respectively. We found that SET and/or hnRNPK protein accumulation increased cellular proliferation. SET accumulation up-regulated hnRNPK mRNA and total/phosphorylated protein, promoted hnRNPK nuclear location, and reduced Bcl-x mRNA levels. SET protein directly interacted with hnRNPK, increasing both its binding to nucleic acids and Bcl-xS repression. We propose that hnRNPK should be a new target of SET and that SET–hnRNPK interaction, in turn, has potential implications in cell survival and malignant transformation.

  12. Magnolol Affects Cellular Proliferation, Polyamine Biosynthesis and Catabolism-Linked Protein Expression and Associated Cellular Signaling Pathways in Human Prostate Cancer Cells in vitro

    Directory of Open Access Journals (Sweden)

    Brendan T. McKeown

    2015-01-01

    Full Text Available Background: Prostate cancer is the most commonly diagnosed form of cancer in men in Canada and the United States. Both genetic and environmental factors contribute to the development and progression of many cancers, including prostate cancer. Context and purpose of this study: This study investigated the effects of magnolol, a compound found in the roots and bark of the magnolia tree Magnolia officinalis, on cellular proliferation and proliferation-linked activities of PC3 human prostate cancer cells in vitro. Results: PC3 cells exposed to magnolol at a concentration of 80 μM for 6 hours exhibited decreased protein expression of ornithine decarboxylase, a key regulator in polyamine biosynthesis, as well as affecting the expression of other proteins involved in polyamine biosynthesis and catabolism. Furthermore, protein expression of the R2 subunit of ribonucleotide reductase, a key regulatory protein associated with DNA synthesis, was significantly decreased. Finally, the MAPK (mitogen-activated protein kinase, PI3K (phosphatidylinositol 3-kinase, NFκB (nuclear factor of kappa-light-chain-enhancer of activated B cells and AP-1 (activator protein 1 cellular signaling pathways were assayed to determine which, if any, of these pathways magnolol exposure would alter. Protein expressions of p-JNK-1 and c-jun were significantly increased while p-p38, JNK-1/2, PI3Kp85, p-PI3Kp85, p-Akt, NFκBp65, p-IκBα and IκBα protein expressions were significantly decreased. Conclusions: These alterations further support the anti-proliferative effects of magnolol on PC3 human prostate cancer cells in vitro and suggest that magnolol may have potential as a novel anti-prostate cancer agent.

  13. microRNA-10b Is Overexpressed and Critical for Cell Survival and Proliferation in Medulloblastoma

    Science.gov (United States)

    Pal, Rekha; Greene, Stephanie

    2015-01-01

    This study demonstrates the effects of miRNA-10b on medulloblastoma proliferation through transcriptional induction of the anti-apoptotic protein BCL2. Using a cancer specific miRNA-array, high expression of miRNA-10b in medulloblastoma cell lines compared to a normal cerebellar control was shown, and this was confirmed with real time PCR (RT-PCR). Two medulloblastoma cell lines (DAOY and UW228) were transiently transfected with control miRNA, miRNA-10b inhibitor or miRNA-10b mimic and subjected to RT-PCR, MTT, apoptosis, clonogenic assay and western blot analysis. Transfection of miRNA-10b inhibitor induced a significant down-regulation of miRNA-10b expression, inhibited proliferation, and induced apoptosis, while miRNA-10b mimic exerted an opposite effect. Inhibition of miRNA-10b abrogated the colony-forming capability of medulloblastoma cells, and markedly down-regulated the expression of BCL2. Down-regulation of BCL2 by antisense oligonucleotides or siRNA also significantly down-regulated miRNA-10b, suggesting that BCL2 is a major mediator of the effects of miRNA-10b. ABT-737 and ABT-199, potent inhibitors of BCL2, downregulated the expression of miRNA-10b and increased apoptosis. Analysis of miRNA-10b levels in 13 primary medulloblastoma samples revealed that the 2 patients with the highest levels of miRNA-10b had multiple recurrences (4.5) and died within 8 years of diagnosis, compared with the 11 patients with low levels of miRNA-10b who had a mean of 1.2 recurrences and nearly 40% long-term survival. The data presented here indicate that miRNA-10b may act as an oncomir in medulloblastoma tumorigenesis, and reveal a previously unreported mechanism with Bcl-2 as a mediator of the effects of miRNA-10b upon medulloblastoma cell survival. PMID:26394044

  14. microRNA-10b Is Overexpressed and Critical for Cell Survival and Proliferation in Medulloblastoma.

    Directory of Open Access Journals (Sweden)

    Rekha Pal

    Full Text Available This study demonstrates the effects of miRNA-10b on medulloblastoma proliferation through transcriptional induction of the anti-apoptotic protein BCL2. Using a cancer specific miRNA-array, high expression of miRNA-10b in medulloblastoma cell lines compared to a normal cerebellar control was shown, and this was confirmed with real time PCR (RT-PCR. Two medulloblastoma cell lines (DAOY and UW228 were transiently transfected with control miRNA, miRNA-10b inhibitor or miRNA-10b mimic and subjected to RT-PCR, MTT, apoptosis, clonogenic assay and western blot analysis. Transfection of miRNA-10b inhibitor induced a significant down-regulation of miRNA-10b expression, inhibited proliferation, and induced apoptosis, while miRNA-10b mimic exerted an opposite effect. Inhibition of miRNA-10b abrogated the colony-forming capability of medulloblastoma cells, and markedly down-regulated the expression of BCL2. Down-regulation of BCL2 by antisense oligonucleotides or siRNA also significantly down-regulated miRNA-10b, suggesting that BCL2 is a major mediator of the effects of miRNA-10b. ABT-737 and ABT-199, potent inhibitors of BCL2, downregulated the expression of miRNA-10b and increased apoptosis. Analysis of miRNA-10b levels in 13 primary medulloblastoma samples revealed that the 2 patients with the highest levels of miRNA-10b had multiple recurrences (4.5 and died within 8 years of diagnosis, compared with the 11 patients with low levels of miRNA-10b who had a mean of 1.2 recurrences and nearly 40% long-term survival. The data presented here indicate that miRNA-10b may act as an oncomir in medulloblastoma tumorigenesis, and reveal a previously unreported mechanism with Bcl-2 as a mediator of the effects of miRNA-10b upon medulloblastoma cell survival.

  15. Immunohistochemical detection of factors related to cellular proliferation and apoptosis in radicular and dentigerous cysts.

    Science.gov (United States)

    Martins, Caroline Alberici; Rivero, Elena Riet Correa; Dufloth, Rozany Mucha; Figueiredo, Cláudia Pinto; Vieira, Daniella Serafin Couto

    2011-01-01

    This study proposed to investigate aspects of cell proliferation and death in the epithelium of radicular (RCs) and dentigerous (DCs) cysts. Serial sections of 17 RCs and 9 DCs were prepared for immunohistochemical detection of caspase-3, Bcl-2, and Ki-67 antigens. Caspase-3 was detected mainly in the suprabasal and superficial epithelial cells of RCs and DCs, whereas Ki-67 was detected predominantly in the basal layer. Both markers had significant expression in hyperplastic epithelium related to an intense inflammation in the capsule. Immunoreactivity for Bcl-2 was restricted to the basal layer and was significantly higher in atrophic epithelium of DCs than that of RCs. These results suggest that epithelial proliferation is balanced by apoptosis and that the presence of inflammation inhibits the Bcl-2 expression. DCs and RCs have different formation mechanisms but have similar biological behavior in the presence of intense inflammatory infiltrate. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. SYNERGISTIC ROLE OF FOOD BIO-MOLECULES IN CELLULAR PROLIFERATION AND CYTOTOXIC ACTIVITY

    OpenAIRE

    A. Mangala Gowri*1 and S. Priya2

    2017-01-01

    Nutrigenomics is the study of molecular relationships between nutritional stimuli andthe response of the genes. The metabolic signals that the nucleus receives from internal factors (hormones) and external factors (nutrients) are responsible for maintaining the functional integrity of genes, with the latter being more influential of environmental stimuli. In response to many types of environmental stimuli including nutrition, the human genomes evolve. Herbs promote proliferation of tissue pro...

  17. Influence of abiotic factors on bacterial proliferation and anoxic survival of the sea mussel Mytilus edulis L.

    NARCIS (Netherlands)

    Babarro, J.M.F.; De Zwaan, A.

    2002-01-01

    The effect of several abiotic factors (salinity, temperature and pH) on bacterial proliferation and survival time of the sea mussel Mytilus edulis L. were studied under anoxic incubations. In addition, the presence in the incubation media of ammonium and the volatile fatty acids propionate and

  18. Effects of protein kinase C activators and staurosporine on protein kinase activity, cell survival, and proliferation in Tetrahymena thermophila

    DEFF Research Database (Denmark)

    Straarup, EM; Schousboe, P; Hansen, HQ

    1997-01-01

    Autocrine factors prevent cell death in the ciliate Tetrahymena thermophila, a unicellular eukaryote, in a chemically defined medium. At certain growth conditions these factors are released at a sufficient concentration by > 500 cells ml-1 to support cell survival and proliferation. The protein k...

  19. Epithelial Xbp1 Is Required for Cellular Proliferation and Differentiation during Mammary Gland Development

    Science.gov (United States)

    Hasegawa, Daisuke; Calvo, Veronica; Avivar-Valderas, Alvaro; Lade, Abigale; Chou, Hsin-I; Lee, Youngmin A.; Farias, Eduardo F.; Aguirre-Ghiso, Julio A.

    2015-01-01

    Xbp1, a key mediator of the unfolded protein response (UPR), is activated by IRE1α-mediated splicing, which results in a frameshift to encode a protein with transcriptional activity. However, the direct function of Xbp1 in epithelial cells during mammary gland development is unknown. Here we report that the loss of Xbp1 in the mammary epithelium through targeted deletion leads to poor branching morphogenesis, impaired terminal end bud formation, and spontaneous stromal fibrosis during the adult virgin period. Additionally, epithelial Xbp1 deletion induces endoplasmic reticulum (ER) stress in the epithelium and dramatically inhibits epithelial proliferation and differentiation during lactation. The synthesis of milk and its major components, α/β-casein and whey acidic protein (WAP), is significantly reduced due to decreased prolactin receptor (Prlr) and ErbB4 expression in Xbp1-deficient mammary epithelium. Reduction of Prlr and ErbB4 expression and their diminished availability at the cell surface lead to reduced phosphorylated Stat5, an essential regulator of cell proliferation and differentiation during lactation. As a result, lactating mammary glands in these mice produce less milk protein, leading to poor pup growth and postnatal death. These findings suggest that the loss of Xbp1 induces a terminal UPR which blocks proliferation and differentiation during mammary gland development. PMID:25713103

  20. Fish oil supplementation associated with decreased cellular degeneration and increased cellular proliferation 6 weeks after middle cerebral artery occlusion in the rat

    Directory of Open Access Journals (Sweden)

    Pascoe MC

    2015-01-01

    Full Text Available Michaela C Pascoe,1 David W Howells, 2David P Crewther,1 Leeanne M Carey,2,3 Sheila G Crewther4 1Brain Sciences Institute, Swinburne University, ²Florey Institute of Neuroscience and Mental Health, University of Melbourne, 3Department of Occupational Therapy, School of Allied Health La Trobe University, 4School of Psychological Science, La Trobe University, Melbourne, VIC, Australia Abstract: Anti-inflammatory long-chain omega-3 polyunsaturated fatty acids (n-3-LC-PUFAs are both neuroprotective and have antidepressive effects. However the influence of dietary supplemented n-3-LC-PUFAs on inflammation-related cell death and proliferation after middle cerebral artery occlusion (MCAo-induced stroke is unknown. We have previously demonstrated that anxiety-like and hyperactive locomotor behaviors are reduced in n-3-LC-PUFA-fed MCAo animals. Thus in the present study, male hooded Wistar rats were exposed to MCAo or sham surgeries and examined behaviorally 6 weeks later, prior to euthanasia and examination of lesion size, cell death and proliferation in the dentate gyrus, cornu ammonis region of the hippocampus of the ipsilesional hemispheres, and the thalamus of the ipsilesional and contralesional hemispheres. Markers of cell genesis and cell degeneration in the hippocampus or thalamus of the ipsilesional hemisphere did not differ between surgery and diet groups 6 weeks post MCAo. Dietary supplementation with n-3-LC-PUFA decreased cell degeneration and increased cell proliferation in the thalamic region of the contralesional hemisphere. MCAo–associated cell degeneration in the hippocampus and thalamus positively correlated with anxiety-like and hyperactive locomotor behaviors previously reported in these animals. These results suggest that anti-inflammatory n-3-LC-PUFA supplementation appears to have cellular protective effects after MCAo in the rat, which may affect behavioral outcomes. Keywords: apoptosis, polyunsaturated fatty acids

  1. Influence of reproductive activity, sex steroids, and seasonality on epigonal organ cellular proliferation in the skate (Leucoraja erinacea).

    Science.gov (United States)

    Lutton, B V; Callard, I P

    2008-01-01

    In elasmobranchs, the epigonal organ, a unique leukopoietic immune tissue, is associated with the gonads. As the ovaries increase in size during reproductive activity, the overall mass of the epigonal organ does not change. However, immunohistochemistry (proliferating cell nuclear antigen Ab) demonstrated more proliferative activity and extravasation of epigonal leukocytes from blood vessels in reproductively active (RA) skates (Leucoraja erinacea) than in non-reproductively active (NRA) skates. In addition, [(3)H]thymidine incorporation was greater in epigonal leukocytes from RA skates than in leukocytes from NRA skates. Plasma from RA skates, but not from NRA skates, increased proliferation of epigonal leukocytes in vitro, an effect that was not seen using steroid-free plasma. In contrast to the stimulatory effect of plasma on leukocyte proliferation, addition of steroids (estrogen, progesterone, testosterone, and dexamethasone) in vitro decreased [(3)H]thymidine incorporation. While the inhibitory response to steroids was seasonally variable, (3)[H]thymidine incorporation was always highest in RA animals, in which plasma steroid levels were also consistently highest. These studies suggest functional interactions between reproductive and immune tissues in the skate, and that cellular turnover in epigonal tissue may be influenced by gonadal activity.

  2. Further studies on the survival of non-proliferating human diploid fibroblasts irradiated with ultraviolet light

    Energy Technology Data Exchange (ETDEWEB)

    Chan, G.L.; Little, J.B. (Harvard Univ., Boston, MA (USA). School of Public Health)

    1982-04-01

    Labelling index data showed that in AG1518 cells, a diploid human fibroblast strain, there was a lag period of at least 14 hours between subculture from the density-inhibited plateau phase of growth and entry into DNA synthesis. Cells irradiated with 254nm wavelength U.V. light 8 hours after subculture did not exhibit the same degree of resistance as cells irradiated in plateau phase and subcultured immediately. When cells were arrested from proliferation by maintenance in an arginine and glutamine deficient medium for 72 hours, they were nearly as resistant to U.V. light as plateau phase cells although maintenance in this medium for 24 hours after irradiation supported further recovery only after low U.V. doses. One strain of Cockayne syndrome fibroblasts was found to be resistant to U.V. light in plateau phase while another strain was found to have the same survival response whether it was irradiated in the plateau or log phase of growth.

  3. Melanoma tumors frequently acquire LRP2/megalin expression, which modulates melanoma cell proliferation and survival rates.

    Science.gov (United States)

    Andersen, Rikke K; Hammer, Katrine; Hager, Henrik; Christensen, Julie N; Ludvigsen, Maja; Honoré, Bent; Thomsen, Mai-Britt H; Madsen, Mette

    2015-05-01

    We show that the multiligand receptor megalin, known to mediate uptake and trafficking of nutrients and signaling molecules, is frequently expressed in malignant melanoma samples. Expression of megalin-encoding mRNA was investigated in 65 samples of nevi, melanomas, and melanoma metastases and was observed in more than 60% of the malignant samples, while only in 20% of the benign counterparts. Megalin expression in nevus and melanoma samples was additionally investigated by immunohistochemistry, which confirmed our mRNA-based observations. We furthermore show that a panel of tumor-derived melanoma cell lines express LRP2/megalin endogenously. In these cells, megalin is internalized from the cell surface and localizes extensively to intracellular vesicles, confirming receptor activity and pointing toward association with the endocytic apparatus. Groundbreaking, our results indicate that sustained megalin expression in melanoma cells is crucial for cell maintenance, as siRNA-mediated reduction in melanoma cell expression of LRP2/megalin significantly decreases melanoma cell proliferation and survival rates. © 2015 The Authors. Pigment Cell & Melanoma Research Published by John Wiley & Sons Ltd.

  4. Isoquercitrin isolated from Hyptis fasciculata reduces glioblastoma cell proliferation and changes beta-catenin cellular localization.

    Science.gov (United States)

    Amado, Nathália G; Cerqueira, Débora M; Menezes, Fabio S; da Silva, Joaquim Fernando Mendes; Neto, Vivaldo Moura; Abreu, Jose G

    2009-08-01

    Isoquercitrin isolated from the aerial parts of Hyptis fasciculata was evaluated according to its capacity to interfere with glioblastoma (Gbm) cell growth. Gbm cells were incubated with isoquercitrin, quercetin, or rutin at concentrations of 25, 50, and 100 mumol/l for 24, 48, and 72 h. Quercetin and rutin affected Gbm cell proliferation after treatment times of longer than 24 h. However, increasing concentrations of isoquercitrin inhibited 50% of Gbm cell proliferation at 24 h and further reached nearly 90% inhibition at 72 h. This effect did not affect cell morphology, cell viability, or cleaved capase-3 levels, indicating that isoquercitrin did not induce Gbm cell death. A marked reduction in cyclin D1 levels and an increase in p27 levels were observed when 100 micromol/l of isoquercitrin was added to Gbm cells. Interestingly, nuclear beta-catenin staining observed in a subpopulation of untreated Gbm cells was found in the cytoplasm after 100-micromol/l isoquercitrin treatment. Collectively, these data show that isoquercitrin reduces Gbm cell growth without inducing apoptosis, possibly by modulating the control of the cell cycle. Our data also suggest that beta-catenin-mediated signaling may be involved on the antiproliferative activity of isoquercitrin.

  5. Proliferation marker pKi-67 occurs in different isoforms with various cellular effects.

    Science.gov (United States)

    Schmidt, Mirko H H; Broll, Rainer; Bruch, Hans-Peter; Finniss, Susan; Bögler, Oliver; Duchrow, Michael

    2004-04-15

    The Ki-67 antigen, pKi-67, is a commonly used proliferation marker in research and pathology. It has been recognized that the protein exists in two different splice variants that differ in one exon. In the current work, we present three new splice variants of human pKi-67 consisting of two naturally occurring isoforms and one atypical version. Additionally, data is presented indicating that alternative splicing of the pKi-67 N-terminus is common in tumor cell lines. Analyzing 93 tissues mainly consisting of brain tumor specimens, we found evidence that long and short isoform can be expressed independently of each other. Induction of mitosis in human peripheral blood mononuclear cells revealed that short pKi-67 appears earlier in the cell cycle than the long isoform and reaches its expression maximum when transcription of the latter sets in. Finally, transfection of mammalian culture cells with exon 7 (specific for the long pKi-67 isoform and not present in the short isoform) in a tetracycline regulated expression system decreased the rate of cell proliferation without affecting the cell cycle. In summary, we present evidence that the pKi-67 N-terminus is differentially spliced resulting in at least five different isoforms with different functions. Copyright 2004 Wiley-Liss, Inc.

  6. Cardiomyocyte Differentiation Promotes Cell Survival During Nicotinamide Phosphoribosyltransferase Inhibition Through Increased Maintenance of Cellular Energy Stores.

    Science.gov (United States)

    Kropp, Erin M; Broniowska, Katarzyna A; Waas, Matthew; Nycz, Alyssa; Corbett, John A; Gundry, Rebekah L

    2017-04-01

    To address concerns regarding the tumorigenic potential of undifferentiated human pluripotent stem cells (hPSC) that may remain after in vitro differentiation and ultimately limit the broad use of hPSC-derivatives for therapeutics, we recently described a method to selectively eliminate tumorigenic hPSC from their progeny by inhibiting nicotinamide phosphoribosyltransferase (NAMPT). Limited exposure to NAMPT inhibitors selectively removes hPSC from hPSC-derived cardiomyocytes (hPSC-CM) and spares a wide range of differentiated cell types; yet, it remains unclear when and how cells acquire resistance to NAMPT inhibition during differentiation. In this study, we examined the effects of NAMPT inhibition among multiple time points of cardiomyocyte differentiation. Overall, these studies show that in vitro cardiomyogenic commitment and continued culturing provides resistance to NAMPT inhibition and cell survival is associated with the ability to maintain cellular ATP pools despite depletion of NAD levels. Unlike cells at earlier stages of differentiation, day 28 hPSC-CM can survive longer periods of NAMPT inhibition and maintain ATP generation by glycolysis and/or mitochondrial respiration. This is distinct from terminally differentiated fibroblasts, which maintain mitochondrial respiration during NAMPT inhibition. Overall, these results provide new mechanistic insight into how regulation of cellular NAD and energy pools change with hPSC-CM differentiation and further inform how NAMPT inhibition strategies could be implemented within the context of cardiomyocyte differentiation. Stem Cells Translational Medicine 2017;6:1191-1201. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  7. The inflammatory microenvironment of the aging prostate facilitates cellular proliferation and hypertrophy.

    Science.gov (United States)

    Begley, L A; Kasina, S; MacDonald, J; Macoska, J A

    2008-08-01

    Benign Prostatic Hypertrophy (BPH, also known as benign prostatic hyperplasia or benign prostatic enlargement), is one of the most common benign proliferative conditions associated with aging in men and is pathologically characterized by the proliferation of fibroblast/myofibroblast and epithelial cell types in the prostate. Previous studies from our laboratory have shown that the CXC-type chemokines, CXCL5 and CXCL12, are secreted by aging prostate stroma and promote both proliferative and transcriptional responses from prostate epithelial cells. Using array-based gene expression profiling and quantitative reverse-transcriptase polymerase chain reaction, we now show that the transcriptome of the aging prostate stroma is characterized by the up-regulation of several genes that encode secreted inflammatory mediators, including secreted CXC-type chemokines (CXCL1, CXCL2, CXCL5, CXCL6, CXCL12), interleukins (IL11, IL33), and transcripts with cytokine homology (CYTL1). At the protein level, ELISA experiments demonstrated that CXCL1, CXCL5, and CXCL6 were secreted by primary prostate stromal fibroblasts explanted from aging prostate stroma. Dose-response assays confirmed that, like CXCL5 and CXCL12, CXCL1 and CXCL6 promote low-level proliferative responses from both prostate stromal fibroblasts and epithelial cells. Taken together, these data suggest that inflammatory mediators are secreted by prostatic stroma consequent to aging, that the levels of these mediators are sufficient to promote low-level increases in the proliferative rate of both epithelial and stromal fibroblast cell types. Moreover, these processes may account for the low-level, but cumulative, proliferation of both epithelial and fibroblastic/myofibroblastic cell types that characterizes the aging-associated development of benign prostatic hypertophy.

  8. Amantadine inhibits cellular proliferation and induces the apoptosis of hepatocellular cancer cells in vitro.

    Science.gov (United States)

    Lan, Zengmei; Chong, Zhaoyang; Liu, Cong; Feng, Danyang; Fang, Dihai; Zang, Weijin; Zhou, Jun

    2015-09-01

    Hepatocellular carcinoma (HCC) is one of the most aggressive malignancies worldwide, and its incidence associated with viral infection has increased in recent years. Amantadine is a tricyclic symmetric amine that can effectively protect against the hepatitis C virus. However, its antitumor properties remain unclear. In the present study, the effects of amantadine on tumor cell viability, cell cycle regulation and apoptosis were investigated. The growth of HepG2 and SMMC‑7721 cells (HCC cell lines) was detected by an MTT assay. Flow cytometry was used to investigate cell cycle regulation and apoptosis. Reverse transcription‑quantitative polymerase chain reaction and western blot analysis were also performed to examine the expression of cell cycle‑ and apoptosis‑related genes and proteins, including cyclin E, cyclin D1, cyclin‑dependent kinase 2 (CDK2), B‑cell lymphoma 2 (Bcl‑2) and Bax. Our results demonstrated that amantadine markedly inhibited the proliferation of HepG2 and SMMC‑7721 cells in a dose‑ and time‑dependent manner and arrested the cell cycle at the G0/G1 phase. The levels of the cell cycle‑related genes and proteins (cyclin D1, cyclin E and CDK2) were reduced by amantadine, and apoptosis was significantly induced. Amantadine treatment also reduced Bcl‑2 and increased the Bax protein and mRNA levels. Additionally, Bcl‑2/Bax ratios were lower in the two HCC cell lines following amantadine treatment. Collectively, these results emphasize the role of amantadine in suppressing proliferation and inducing apoptosis in HCC cells, advocating its use as a novel tumor-suppressive therapeutic candidate.

  9. Survival and proliferation characteristics of the microalga Chlamydomonas sp. ICE-L after hypergravitational stress pretreatment

    Science.gov (United States)

    Gao, Zhengquan; Li, Demao; Meng, Chunxiao; Xu, Dong; Zhang, Xiaowen; Ye, Naihao

    2013-09-01

    Seeking extraterrestrial life, transferring between planets, even migrating to other planets attracts more and more attention of public and scientists. However, to make it clear for the ability to survive the forces studies is prerequisite to enable the speculations by natural means. Gravity is a critical force involved in all the life on Earth and, possibly, others planets. Organisms have been grown in microgravity habitats and in centrifuges to characterize the biological response to a range of gravitational forces and radiation levels in space and on Earth. However, little is known about the profiles of eukaryotic life under conditions of hyperacceleration attributable to extreme gravities. In this study, a eukaryotic extremophile, the Antarctic green microalga Chlamydomonas sp. ICE-L, showed amazing proliferation capacity during and after hypergravitational stress for 30 min to 48 h at 110,200, 423,400, and 670,800g. These extreme gravities also had profound effects on viability, reproduction rate, photosynthesis efficiency, and gene transcriptional expression of this microalga. Most notably, all three supergravities efficiently stimulated algal cell division, but the greater the centrifugal force and the longer the duration of treatment, the lower the viable rate and breeding potential of samples in the following incubation. These results illustrated Chlamydomonas sp. ICE-L is a useful eukaryotic model system candidate for space research. Further studies could provide new insight into the physical limits of life and its evolution and enhance the possibility for interstellar space travel and the quest for extraterrestrial life according to panspermia theory. Also, it indicated that life come from the outer space is not always prokaryotes but may be eukaryotes.

  10. TRPV1 mediates cellular uptake of anandamide and thus promotes endothelial cell proliferation and network-formation

    Directory of Open Access Journals (Sweden)

    Nicole A. Hofmann

    2014-11-01

    Full Text Available Anandamide (N-arachidonyl ethanolamide, AEA is an endogenous cannabinoid that is involved in various pathological conditions, including cardiovascular diseases and tumor-angiogenesis. Herein, we tested the involvement of classical cannabinoid receptors (CBRs and the Ca2+-channel transient receptor potential vanilloid 1 (TRPV1 on cellular AEA uptake and its effect on endothelial cell proliferation and network-formation. Uptake of the fluorescence-labeled anandamide (SKM4-45-1 was monitored in human endothelial colony-forming cells (ECFCs and a human endothelial-vein cell line (EA.hy926. Involvement of the receptors during AEA translocation was determined by selective pharmacological inhibition (AM251, SR144528, CID16020046, SB366791 and molecular interference by TRPV1-selective siRNA-mediated knock-down and TRPV1 overexpression. We show that exclusively TRPV1 contributes essentially to AEA transport into endothelial cells in a Ca2+-independent manner. This TRPV1 function is a prerequisite for AEA-induced endothelial cell proliferation and network-formation. Our findings point to a so far unknown moonlighting function of TRPV1 as Ca2+-independent contributor/regulator of AEA uptake. We propose TRPV1 as representing a promising target for development of pharmacological therapies against AEA-triggered endothelial cell functions, including their stimulatory effect on tumor-angiogenesis.

  11. Lack of potassium channel induces proliferation and survival causing increased neurogenesis and two-fold hippocampus enlargement

    DEFF Research Database (Denmark)

    Almgren, Malin; Persson, Ann-Sophie; Fenghua, Chen

    2007-01-01

    and the second week of life. To investigate the hyperplasia, cell proliferation was studied within the subgranular zone of the DG using BrdU and Ki67. There was a three-fold increase in proliferation in mceph/mceph mice compared to wild type mice at an age before onset of epileptic symptoms (3 weeks...... was lower in mceph/mceph supporting additional overgrowth mechanism than induced by seizures. In conclusion, lack of a functional Kv1.1 ion channel subunit in the mceph/mceph mice causes a unique neuronal hyperplasia in distinct hippocampal regions and consequently hippocampal enlargement from 2 to 3 weeks...... of age. This phenotype is a result, at least in DG, from increased proliferation, neurogenesis, and enhanced general hippocampal cell survival. Udgivelsesdato: 2007-null...

  12. N-cadherin negatively regulates osteoblast proliferation and survival by antagonizing Wnt, ERK and PI3K/Akt signalling.

    Directory of Open Access Journals (Sweden)

    Eric Haÿ

    Full Text Available BACKGROUND: Osteoblasts are bone forming cells that play an essential role in osteogenesis. The elucidation of the mechanisms that control osteoblast number is of major interest for the treatment of skeletal disorders characterized by abnormal bone formation. Canonical Wnt signalling plays an important role in the control of osteoblast proliferation, differentiation and survival. Recent studies indicate that the cell-cell adhesion molecule N-cadherin interacts with the Wnt co-receptors LRP5/6 to regulate osteoblast differentiation and bone accrual. The role of N-cadherin in the control of osteoblast proliferation and survival remains unknown. METHODS AND PRINCIPAL FINDINGS: Using murine MC3T3-E1 osteoblastic cells and N-cadherin transgenic mice, we demonstrate that N-cadherin overexpression inhibits cell proliferation in vitro and in vivo. The negative effect of N-cadherin on cell proliferation results from decreased Wnt, ERK and PI3K/Akt signalling and is restored by N-cadherin neutralizing antibody that antagonizes N-cadherin-LRP5 interaction. Inhibition of Wnt signalling using DKK1 or Sfrp1 abolishes the ability of N-cadherin blockade to restore ERK and PI3K signalling and cell proliferation, indicating that the altered cell growth in N-cadherin overexpressing cells is in part secondary to alterations in Wnt signalling. Consistently, we found that N-cadherin overexpression inhibits the expression of Wnt3a ligand and its downstream targets c-myc and cyclin D1, an effect that is partially reversed by N-cadherin blockade. We also show that N-cadherin overexpression decreases osteoblast survival in vitro and in vivo. This negative effect on cell survival results from inhibition of PI3K/Akt signalling and increased Bax/Bcl-2, a mechanism that is rescued by Wnt3a. CONCLUSION: The data show that N-cadherin negatively controls osteoblast proliferation and survival via inhibition of autocrine/paracrine Wnt3a ligand expression and attenuation of Wnt

  13. Tensin2 is a novel mediator in thrombopoietin (TPO)-induced cellular proliferation by promoting Akt signaling.

    Science.gov (United States)

    Jung, Andre Scott; Kaushansky, Alexis; Macbeath, Gavin; Kaushansky, Kenneth

    2011-06-01

    Thrombopoietin (TPO) and its receptor c-Mpl are essential in the regulation of the hematopoietic stem and progenitors cells as well as for the differentiation of megakaryocytes into mature platelets. Once TPO binds to its receptor, an intracellular signaling process is initiated through Janus kinase (JAK-2)-induced phosphorylation of the c-Mpl intracellular domain. Although some protein mediators that transmit the effects of TPO have been identified, many remain undiscovered. Using an unbiased approach with peptide microarrays that contained virtually every Src Homology (SH)2 and Phosphotyrosine Binding (PTB) domains in the human genome, we discovered a previously unreported interaction between c-Mpl at phospho-Tyrosine631 (pY 631) and Tensin2, a protein for which limited information is available. Confirming the findings of the microarrays, we discovered that Tensin2 co-precipitates with a pY 631 bearing peptide. Furthermore, we found that Tensin2 becomes phosphorylated in a TPO dependent manner. The functional consequence of Tensin2 was tested via knockdown of Tensin2, which dramatically decreased TPO-dependent cellular proliferation of UT7-TPO cell line as well as their activation of Akt signaling. These studies affirm the use of these arrays as an unbiased screening tool of protein-protein interactions. We conclude that Tensin2 is an important new mediator in TPO/c-Mpl pathway and has a positive affect on cellular growth, at least in part through its effect on the PI3K/Akt signaling.

  14. Cellular proliferation and infiltration following interstitial irradiation of normal dog brain is altered by an inhibitor of polyamine synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Fike, J.R.; Gobbel, G.T.; Chou, D. [Univ. of California, San Francisco, CA (United States)] [and others

    1995-07-15

    The objectives of this study were to quantitatively define proliferative and infiltrative cell responses after focal {sup 125}I irradiation of normal brain, and to determine the effects of an intravenous infusion of {alpha}-defluoromethylornithine (DFMO) on those responses. Adult beagle dogs were irradiated using high activity {sup 125}I sources. Cellular responses were quantified using a histomorphometric analysis. After radiation alone, cellular events included a substantial acute inflammatory response followed by increased BrdU labeling and progressive increases in numbers of capillaries and astrocytes. {alpha}-Difluoromethylornithine treatment significantly affected the measured cell responses. As in controls, an early inflammatory response was measured, but after 2 weeks there were more PMNs/unit area than in controls. The onset of measurable BrdU labeling was delayed in DFMO-treated animals, and the magnitude of labeling was significantly reduced. Increases in astrocyte and vessel numbers/mm{sup 2} were observed after a 2-week delay. At the site of implant, astrocytes from DFMO-treated dogs were significantly smaller than those from controls. There is substantial cell proliferation and infiltration in response to interstitial irradiation of normal brain, and these responses are significantly altered by DFMO treatment. Although the precise mechanisms by which DFMO exerts its effects in this model are not known, the results from this study suggest that modification of radiation injury may be possible by manipulating the response of normal cells to injury. 57 refs., 6 figs.

  15. BRCA1 haploinsufficiency leads to altered expression of genes involved in cellular proliferation and development.

    Directory of Open Access Journals (Sweden)

    Harriet E Feilotter

    Full Text Available The assessment of BRCA1 and BRCA2 coding sequences to identify pathogenic mutations associated with inherited breast/ovarian cancer syndrome has provided a method to identify high-risk individuals, allowing them to seek preventative treatments and strategies. However, the current test is expensive, and cannot differentiate between pathogenic variants and those that may be benign. Focusing only on one of the two BRCA partners, we have developed a biological assay for haploinsufficiency of BRCA1. Using a series of EBV-transformed cell lines, we explored gene expression patterns in cells that were BRCA1 wildtype compared to those that carried (heterozygous BRCA1 pathogenic mutations. We identified a subset of 43 genes whose combined expression pattern is a sensitive predictor of BRCA1 status. The gene set was disproportionately made up of genes involved in cellular differentiation, lending credence to the hypothesis that single copy loss of BRCA1 function may impact differentiation, rendering cells more susceptible to undergoing malignant processes.

  16. Breast cancer cellular proliferation indexes and 99mTc-sesta Mibi capture: what correlation?

    Science.gov (United States)

    Bonazzi, G; Cistaro, A; Bellò, M; Bessone, M; Tetti, M; Villata, E; Coluccia, C; Ardine, M; Moz, G; Massaioli, N; Bisi, G

    2001-03-01

    Aim of this study was to verify existing correlations between breast cancer 99mTc-sestaMIBI cells uptake and their cytological characteristics. Forty-five patients with clinically and/or mammographically suspect breast cancer were enrolled. In all patients 99mTc-sestaMIBI scintimammography was performed and malignant lesions were detected in 44 cases and benign in one case. In positive uptake (PU) lesions with diameter <1.5cm, 85.7% showed a high tumor grade (II-III degrees) while in negative uptake (NU) lesions with diameter <1.5cm, 100% showed a low tumor grade (I degrees). In PU lesions, 70% had expressed a high value of Ki 67, while 100% of the NU lesions showed normal values. In this series, tumor diameter does not play a basic role, while the correlations between uptake and the histological grade (G) and/or cellular kinetics (Ki67) seem to be more important. Further studies are needed to confirm our present results.

  17. HIV aspartyl peptidase inhibitors interfere with cellular proliferation, ultrastructure and macrophage infection of Leishmania amazonensis.

    Directory of Open Access Journals (Sweden)

    Lívia O Santos

    Full Text Available BACKGROUND: Leishmania is the etiologic agent of leishmanisais, a protozoan disease whose pathogenic events are not well understood. Current therapy is suboptimal due to toxicity of the available therapeutic agents and the emergence of drug resistance. Compounding these problems is the increase in the number of cases of Leishmania-HIV coinfection, due to the overlap between the AIDS epidemic and leishmaniasis. METHODOLOGY/PRINCIPAL FINDINGS: In the present report, we have investigated the effect of HIV aspartyl peptidase inhibitors (PIs on the Leishmania amazonensis proliferation, ultrastructure, interaction with macrophage cells and expression of classical peptidases which are directly involved in the Leishmania pathogenesis. All the HIV PIs impaired parasite growth in a dose-dependent fashion, especially nelfinavir and lopinavir. HIV PIs treatment caused profound changes in the leishmania ultrastructure as shown by transmission electron microscopy, including cytoplasm shrinking, increase in the number of lipid inclusions and some cells presenting the nucleus closely wrapped by endoplasmic reticulum resembling an autophagic process, as well as chromatin condensation which is suggestive of apoptotic death. The hydrolysis of HIV peptidase substrate by L. amazonensis extract was inhibited by pepstatin and HIV PIs, suggesting that an aspartyl peptidase may be the intracellular target of the inhibitors. The treatment with HIV PIs of either the promastigote forms preceding the interaction with macrophage cells or the amastigote forms inside macrophages drastically reduced the association indexes. Despite all these beneficial effects, the HIV PIs induced an increase in the expression of cysteine peptidase b (cpb and the metallopeptidase gp63, two well-known virulence factors expressed by Leishmania spp. CONCLUSIONS/SIGNIFICANCE: In the face of leishmaniasis/HIV overlap, it is critical to further comprehend the sophisticated interplays among Leishmania

  18. Survival and proliferation of alginate encapsulated Trichoderma spp. in Egyptian soil in comparison with allyl alcohol soil fumigation.

    Science.gov (United States)

    Shaban, G M; El-Komy, H M

    2001-01-01

    Conidia of Trichoderma harzianum and T. pseudokoningii (Rifai) were formulated to make alginate pellets with or without 10% cellulose as a food-base material. The formulations were compared for their ability for survival and proliferation of Trichoderma spp. in clay-loamy soil (50% moisture content) with allyl alcohol fumigation (0.05, 0.1 and 0.2 ml/1,000 ml space). Trichoderma medium E (TME) containing 100 microg/ml pentachloronitrobenzene (PCNB) was valuable for isolation and counting of Trichoderma spp. from the tested soil than the Glucose-Czapek's agar medium containing 1:15,000 Rose-bengal. The promotive effect of Trichoderma by different doses of allyl alcohol fumigation still enhanced after two-month incubation period. Conidia entrapped in alginate with or without cellulose and introduced into the soil survived better than conidia added directly to the same soil after three months incubation period. Sterile soil provided a more favorable environment for the proliferation and survival of immobilized conidia than the non-sterile soil, and the addition of 10% cellulose increased the survival of the entrapped conidia more than those prepared without cellulose. Soil fumigation inhibited the occurrence of other fungal species; however, inoculation of the soil with alginate immobilized conidia or conidial suspension had such inhibitory effect but in a less extent.

  19. MiR-9, -31, and -182 deregulation promote proliferation and tumor cell survival in colon cancer.

    Science.gov (United States)

    Cekaite, Lina; Rantala, Juha K; Bruun, Jarle; Guriby, Marianne; Agesen, Trude H; Danielsen, Stine A; Lind, Guro E; Nesbakken, Arild; Kallioniemi, Olli; Lothe, Ragnhild A; Skotheim, Rolf I

    2012-09-01

    Several microRNAs (miRNAs) are known to be deregulated in colon cancer, but the mechanisms behind their potential involvement on proliferation and tumor cell survival are unclear. The present study aimed to identify miRNAs with functional implications for development of colon cancer. The cell proliferation and apoptosis were examined following perturbations of miRNA levels by employing a comprehensive miRNA library screen. miRNAs nominated for relevance to colon cancer were validated on expression and functional levels. By integrating the effect of miRNA up-regulation with the endogenous miRNA expression levels within the HT29, HCT116, and SW480 colon cancer cell lines, we identified miRNAs controlling cell proliferation (n = 53) and apoptosis (n = 93). From these functionally nominated miRNAs, we narrowed the list to 10 oncogene- and 20 tumor suppressor-like miRNAs that were also differentially expressed between colon cancer (n = 80) and normal colonic mucosa (n = 20). The differential expressions of miR-9, miR-31, and miR-182 were successfully validated in a series of colon carcinomas (n = 30) and polyps (n = 10) versus normal colonic mucosa (n = 10), whereas the functional effect was confirmed in an in-depth validation using different cell viability and apoptotic markers. Several transcription factors and genes regulating cell proliferation were identified as putative target genes by integrative miRNA/mRNA expression analysis obtained from the same colon cancer patient samples. This study suggests that deregulated expression of miR-9, miR-31, and miR-182 during carcinogenesis plays a significant role in the development of colon cancer by promoting proliferation and tumor cell survival.

  20. MiR-9, -31, and -182 Deregulation Promote Proliferation and Tumor Cell Survival in Colon Cancer12

    Science.gov (United States)

    Cekaite, Lina; Rantala, Juha K; Bruun, Jarle; Guriby, Marianne; Ågesen, Trude H; Danielsen, Stine A; Lind, Guro E; Nesbakken, Arild; Kallioniemi, Olli; Lothe, Ragnhild A; Skotheim, Rolf I

    2012-01-01

    Several microRNAs (miRNAs) are known to be deregulated in colon cancer, but the mechanisms behind their potential involvement on proliferation and tumor cell survival are unclear. The present study aimed to identify miRNAs with functional implications for development of colon cancer. The cell proliferation and apoptosis were examined following perturbations of miRNA levels by employing a comprehensive miRNA library screen. miRNAs nominated for relevance to colon cancer were validated on expression and functional levels. By integrating the effect of miRNA up-regulation with the endogenous miRNA expression levels within the HT29, HCT116, and SW480 colon cancer cell lines, we identified miRNAs controlling cell proliferation (n = 53) and apoptosis (n = 93). From these functionally nominated miRNAs, we narrowed the list to 10 oncogene- and 20 tumor suppressor-like miRNAs that were also differentially expressed between colon cancer (n = 80) and normal colonic mucosa (n = 20). The differential expressions of miR-9, miR-31, and miR-182 were successfully validated in a series of colon carcinomas (n = 30) and polyps (n = 10) versus normal colonic mucosa (n = 10), whereas the functional effect was confirmed in an in-depth validation using different cell viability and apoptotic markers. Several transcription factors and genes regulating cell proliferation were identified as putative target genes by integrative miRNA/mRNA expression analysis obtained from the same colon cancer patient samples. This study suggests that deregulated expression of miR-9, miR-31, and miR-182 during carcinogenesis plays a significant role in the development of colon cancer by promoting proliferation and tumor cell survival. PMID:23019418

  1. MiR-9, -31, and -182 Deregulation Promote Proliferation and Tumor Cell Survival in Colon Cancer

    Directory of Open Access Journals (Sweden)

    Lina Cekaite

    2012-09-01

    Full Text Available Several microRNAs (miRNAs are known to be deregulated in colon cancer, but the mechanisms behind their potential involvement on proliferation and tumor cell survival are unclear. The present study aimed to identify miRNAs with functional implications for development of colon cancer. The cell proliferation and apoptosis were examined following perturbations of miRNA levels by employing a comprehensive miRNA library screen. miRNAs nominated for relevance to colon cancer were validated on expression and functional levels. By integrating the effect of miRNA up-regulation with the endogenous miRNA expression levels within the HT29, HCT116, and SW480 colon cancer cell lines, we identified miRNAs controlling cell proliferation (n = 53 and apoptosis (n = 93. From these functionally nominated miRNAs, we narrowed the list to 10 oncogene- and 20 tumor suppressor-like miRNAs that were also differentially expressed between colon cancer (n = 80 and normal colonic mucosa (n = 20. The differential expressions of miR-9, miR-31, and miR-182 were successfully validated in a series of colon carcinomas (n = 30 and polyps (n = 10 versus normal colonic mucosa (n = 10, whereas the functional effect was confirmed in an in-depth validation using different cell viability and apoptotic markers. Several transcription factors and genes regulating cell proliferation were identified as putative target genes by integrative miRNA/mRNA expression analysis obtained from the same colon cancer patient samples. This study suggests that deregulated expression of miR-9, miR-31, and miR-182 during carcinogenesis plays a significant role in the development of colon cancer by promoting proliferation and tumor cell survival.

  2. Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joon-Seok; Lee, Cheol-Koo, E-mail: cklee2005@korea.ac.kr

    2013-09-13

    Highlights: •CR decreases total ROS and mitochondrial superoxide during the chronological aging. •CR does not affect the levels of oxidative damage on protein and DNA. •CR contributes extension of chronological lifespan by maintenance of ATP level -- Abstract: The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA.

  3. 3-hydroxykynurenine suppresses CD4+ T-cell proliferation, induces T-regulatory-cell development, and prolongs corneal allograft survival.

    Science.gov (United States)

    Zaher, Sarah S; Germain, Conrad; Fu, Hongmei; Larkin, Daniel F P; George, Andrew J T

    2011-04-01

    IDO (indoleamine 2,3-dioxygenase) modulates the immune response by depletion of the essential amino acid tryptophan, and IDO overexpression has been shown to prolong corneal allograft survival. This study was conducted to examine the effect of kynurenines, the products of tryptophan breakdown and known to act directly on T lymphocytes, on corneal graft survival. The effects of kynurenines on T-cell proliferation and death, T-regulatory-cell development, and dendritic cell function, phenotype, and viability were analyzed in vitro. The effect of topical and systemic administration of 3-hydroxykynurenine (3HK) on orthotopic murine corneal allograft survival was examined. T-lymphocyte proliferation was inhibited by two of the four different kynurenines: 3HK and 3-hydroxyanthranilic acid (3HAA). This effect was accompanied by significant T-cell death. Neither 3HK nor 3HAA altered dendritic cell function, nor did they induce apoptosis or pathogenicity to corneal endothelial cells. Administration of systemic and topical 3HK to mice receiving a fully mismatched corneal graft resulted in significant prolongation of graft survival (median survival of control grafts, 12 days; of treated, 19 and 15 days, respectively; P < 0.0003). While systemic administration of 3HK was associated with a significant depletion of CD4(+) T, CD8(+) T, and B lymphocytes in peripheral blood, no depletion was found after topical administration. The production of kynurenines, in particular 3HK and 3HAA, may be one mechanism (in addition to tryptophan depletion) by which IDO prolongs graft survival. These molecules have potential as specific agents for preventing allograft rejection in patients at high rejection risk.

  4. Effects of octreotide and insulin on colon cancer cellular proliferation and correlation with hTERT activity.

    Science.gov (United States)

    Ayiomamitis, Georgios D; Notas, George; Zaravinos, Apostolos; Drygiannakis, Ioannis; Georgiadou, Maria; Sfakianaki, Ourania; Mastrodimou, Niki; Thermos, Kyriaki; Kouroumalis, Elias

    2014-01-01

    Peptide hormone somatostatin and its receptors have a wide range of physiological functions and play a role in the treatment of numerous human diseases, including colorectal cancer. Octreotide, a synthetic somatostatin-analog peptide, inhibits growth of colonic cancer cells primarily by binding to G-protein coupled receptors and elicits cellular responses through second-messenger systems. Insulin also initiates mitogenic signals in certain cell types. The objective of the present study was to explore the effects of octreotide with or without insulin treatment, on Caco-2 and HT-29 human colon-cancer cell proliferation and to correlate their effects with the activation of telomerase reverse transcriptase (hTERT). The involvement of protein tyrosine phosphatases in the regulation of the anti-proliferative effect of octreotide was also evaluated. Sodium orthovanadate was used to reverse the anti- proliferative effect of octreotide. Telomerase activity was determined for each time point under octreotide and/or insulin treatment. Elevated expression of sst1, sst2 and sst5 was confirmed in both cell lines by RT-PCR. Immunocytochemistry detected sst1, sst2A, sst2B, sst3, sst4 and sst5 protein expression in the membranes of both cell lines. Octreotide inhibited the proliferation of Caco-2 and HT-29 cells in a time and dose-dependent manner. Insulin exerted proliferative effects in Caco-2 cells and octreotide reversed its effect in both cell lines. Sodium orthovanadate suppressed the anti-proliferative effect of octreotide both in Caco-2 and HT-29 cells. Telomerase activity was significantly reduced when Caco-2 cells were exposed to octreotide, under serum-free cultured medium. On the other hand, telomerase attenuation after octreotide treatment could not counteract the actions of insulin on both cells. Our data indicate that the use of octreotide could provide a possible therapeutic approach to the management of certain patients who suffer from colon cancer.

  5. Effects of octreotide and insulin on colon cancer cellular proliferation and correlation with hTERT activity

    Science.gov (United States)

    Ayiomamitis, Georgios D.; Notas, George; Zaravinos, Apostolos; Drygiannakis, Ioannis; Georgiadou, Maria; Sfakianaki, Ourania; Mastrodimou, Niki; Thermos, Kyriaki; Kouroumalis, Elias

    2014-01-01

    Peptide hormone somatostatin and its receptors have a wide range of physiological functions and play a role in the treatment of numerous human diseases, including colorectal cancer. Octreotide, a synthetic somatostatin-analog peptide, inhibits growth of colonic cancer cells primarily by binding to G-protein coupled receptors and elicits cellular responses through second-messenger systems. Insulin also initiates mitogenic signals in certain cell types. The objective of the present study was to explore the effects of octreotide with or without insulin treatment, on Caco-2 and HT-29 human colon-cancer cell proliferation and to correlate their effects with the activation of telomerase reverse transcriptase (hTERT). The involvement of protein tyrosine phosphatases in the regulation of the anti-proliferative effect of octreotide was also evaluated. Sodium orthovanadate was used to reverse the anti- proliferative effect of octreotide. Telomerase activity was determined for each time point under octreotide and/or insulin treatment. Elevated expression of sst1, sst2 and sst5 was confirmed in both cell lines by RT-PCR. Immunocytochemistry detected sst1, sst2A, sst2B, sst3, sst4 and sst5 protein expression in the membranes of both cell lines. Octreotide inhibited the proliferation of Caco-2 and HT-29 cells in a time and dose-dependent manner. Insulin exerted proliferative effects in Caco-2 cells and octreotide reversed its effect in both cell lines. Sodium orthovanadate suppressed the anti-proliferative effect of octreotide both in Caco-2 and HT-29 cells. Telomerase activity was significantly reduced when Caco-2 cells were exposed to octreotide, under serum-free cultured medium. On the other hand, telomerase attenuation after octreotide treatment could not counteract the actions of insulin on both cells. Our data indicate that the use of octreotide could provide a possible therapeutic approach to the management of certain patients who suffer from colon cancer. PMID:25594044

  6. Epstein-Barr virus nuclear antigen 3A promotes cellular proliferation by repression of the cyclin-dependent kinase inhibitor p21WAF1/CIP1.

    Directory of Open Access Journals (Sweden)

    Melissa L Tursiella

    2014-10-01

    Full Text Available Latent infection by Epstein-Barr virus (EBV is highly associated with the endemic form of Burkitt lymphoma (eBL, which typically limits expression of EBV proteins to EBNA-1 (Latency I. Interestingly, a subset of eBLs maintain a variant program of EBV latency - Wp-restricted latency (Wp-R - that includes expression of the EBNA-3 proteins (3A, 3B and 3C, in addition to EBNA-1. In xenograft assays, Wp-R BL cell lines were notably more tumorigenic than their counterparts that maintain Latency I, suggesting that the additional latency-associated proteins expressed in Wp-R influence cell proliferation and/or survival. Here, we evaluated the contribution of EBNA-3A. Consistent with the enhanced tumorigenic potential of Wp-R BLs, knockdown of EBNA-3A expression resulted in abrupt cell-cycle arrest in G0/G1 that was concomitant with conversion of retinoblastoma protein (Rb to its hypophosphorylated state, followed by a loss of Rb protein. Comparable results were seen in EBV-immortalized B lymphoblastoid cell lines (LCLs, consistent with the previous observation that EBNA-3A is essential for sustained growth of these cells. In agreement with the known ability of EBNA-3A and EBNA-3C to cooperatively repress p14(ARF and p16(INK4a expression, knockdown of EBNA-3A in LCLs resulted in rapid elevation of p14(ARF and p16I(NK4a. By contrast, p16(INK4a was not detectably expressed in Wp-R BL and the low-level expression of p14(ARF was unchanged by EBNA-3A knockdown. Amongst other G1/S regulatory proteins, only p21(WAF1/CIP1, a potent inducer of G1 arrest, was upregulated following knockdown of EBNA-3A in Wp-R BL Sal cells and LCLs, coincident with hypophosphorylation and destabilization of Rb and growth arrest. Furthermore, knockdown of p21(WAF1/CIP1 expression in Wp-R BL correlated with an increase in cellular proliferation. This novel function of EBNA-3A is distinct from the functions previously described that are shared with EBNA-3C, and likely contributes to

  7. RELM-β promotes human pulmonary artery smooth muscle cell proliferation via FAK-stimulated surviving

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chunlong, E-mail: lclmd@sina.com; Li, Xiaohui; Luo, Qiong; Yang, Hui; Li, Lun; Zhou, Qiong; Li, Yue; Tang, Hao; Wu, Lifu

    2017-02-01

    Resistin-like molecule-β (RELM-β), focal adhesion kinase (FAK), and survivin may be involved in the proliferation of cultured human pulmonary artery smooth muscle cells (HPAMSCs), which is involved in pulmonary hypertension. HPAMSCs were treated with human recombinant RELM-β (rhRELM-β). siRNAs against FAK and survivin were transfected into cultured HPASMCs. Expression of FAK and survivin were examined by RT-PCR and western blot. Immunofluorescence was used to localize FAK. Flow cytometry was used to examine cell cycle distribution and cell death. Compared to the control group, all rhRELM-β-treated groups demonstrated significant increases in the expression of FAK and survivin (P<0.05). rhRELM-β significantly increased the proportion of HPASMCs in the S phase and decreased the proportion in G0/G1. FAK siRNA down-regulated survivin expression while survivin siRNA did not affect FAK expression. FAK siRNA effectively inhibited FAK and survivin expression in RELM-β-treated HPASMCs and partially suppressed cell proliferation. RELM-β promoted HPASMC proliferation and upregulated FAK and survivin expression. In conclusion, results suggested that FAK is upstream of survivin in the signaling pathway mediating cell proliferation. FAK seems to be important in RELM-β-induced HPASMC proliferation, partially by upregulating survivin expression. - Highlights: • rhRELM-β increased the expression of FAK and survivin. • rhRELM-β increased the proportion of HPASMCs in the S phase. • FAK is upstream of survivin in the signaling pathway mediating cell proliferation. • FAK is important in RELM-β-induced HPASMC proliferation, partly via survivin.

  8. Diurnal variations in proliferation and crypt survival suggest a small target cell population in mouse colon

    Energy Technology Data Exchange (ETDEWEB)

    Dobbin, J.; Hamilton, E.

    1986-01-01

    Male C57BLasup(t) mice of two ages, 3-5 months (young) and 14-15 months (old) were given 11 or 15Gy whole body irradiation at different times through the day. The mice were killed after 4.5 days and the number of surviving crypts per circumference of jejunum, ileum, transverse colon and descending colon were scored. These results show crypt survival in the small and large intestine of 15-month-old mice. In the ileum the maximum crypt survival was found at 04.00 h and the minimum at 08.00 h. In the jejunum and both regions of the colon the maximum crypt survival occurred at 16.00 h. The nadir of crypt survival after 15 Gy was at 04.00 h in the jejunum and at 20.00 and 24.00 h in the transverse and descending colon, respectively. In young mice, crypt survival levels were similar to those found in old animals except at 04.00 h. when survival in the jejunum and ileum fell to 0.0004+-0.0002 and 0.0007+-0.0004, respectively. The lowest crypt survival in the colon of young mice also occurred at 04.00 h and in all four tissues the greatest number of crypts survived irradiation at 24.00 h.

  9. Int6/eIF3e Is Essential for Proliferation and Survival of Human Glioblastoma Cells

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    Julie Sesen

    2014-01-01

    Full Text Available Glioblastomas (GBM are very aggressive and malignant brain tumors, with frequent relapses despite an appropriate treatment combining surgery, chemotherapy and radiotherapy. In GBM, hypoxia is a characteristic feature and activation of Hypoxia Inducible Factors (HIF-1α and HIF-2α has been associated with resistance to anti-cancer therapeutics. Int6, also named eIF3e, is the “e” subunit of the translation initiation factor eIF3, and was identified as novel regulator of HIF-2α. Eukaryotic initiation factors (eIFs are key factors regulating total protein synthesis, which controls cell growth, size and proliferation. The functional significance of Int6 and the effect of Int6/EIF3E gene silencing on human brain GBM has not yet been described and its role on the HIFs is unknown in glioma cells. In the present study, we show that Int6/eIF3e suppression affects cell proliferation, cell cycle and apoptosis of various GBM cells. We highlight that Int6 inhibition induces a diminution of proliferation through cell cycle arrest and increased apoptosis. Surprisingly, these phenotypes are independent of global cell translation inhibition and are accompanied by decreased HIF expression when Int6 is silenced. In conclusion, we demonstrate here that Int6/eIF3e is essential for proliferation and survival of GBM cells, presumably through modulation of the HIFs.

  10. Evaluation of Residual Cellularity and Proliferation on Preoperatively Treated Breast Cancer: A Comparison between Image Analysis and Light Microscopy Analysis

    Directory of Open Access Journals (Sweden)

    Valentina Corletto

    1998-01-01

    Full Text Available Histopathology has been suggested as a reliable method for tumour reduction evaluation of preoperatively treated breast cancer. Immunocytochemistry can be used to enhance the visibility of residual tumour cellularity and in the evaluation of its proliferative activity. We compared Image Analysis (IA with Light Microscopy Analysis (LMA on sections of breast carcinomas treated with preoperative chemo‐ or chemo/radiotherapy in the evaluation of the Neoplastic Cell Density (NCD (69 cases and the Proliferation Index (PI (35 cases. NCD was expressed as the immunoreactive area to cytokeratin over the total original neoplastic area and PI was expressed as the number of immunostained tumoural nuclei with MIB1 MoAb over the total of tumoural nuclei. The intraobserver agreement and that between IA and LMA for both indices were estimated by the common (Kw and the jackknife weighted kappa statistic (K˜w. The extent of agreement of each considered category was also assessed by means of the category‐specific kappa statistics (Kcs. The intraobserver agreement within LMA for NCD and PI and that between IA and LMA for PI were both satisfactory. Upon evaluation of the NCD, the agreement between IA and LMA showed unsatisfactory results, especially when the ratio between the residual tumour cells and the background was critical.

  11. Metabolic and protein interaction sub-networks controlling the proliferation rate of cancer cells and their impact on patient survival.

    Science.gov (United States)

    Feizi, Amir; Bordel, Sergio

    2013-10-24

    Cancer cells can have a broad scope of proliferation rates. Here we aim to identify the molecular mechanisms that allow some cancer cell lines to grow up to 4 times faster than other cell lines. The correlation of gene expression profiles with the growth rate in 60 different cell lines has been analyzed using several genome-scale biological networks and new algorithms. New possible regulatory feedback loops have been suggested and the known roles of several cell cycle related transcription factors have been confirmed. Over 100 growth-correlated metabolic sub-networks have been identified, suggesting a key role of simultaneous lipid synthesis and degradation in the energy supply of the cancer cells growth. Many metabolic sub-networks involved in cell line proliferation appeared also to correlate negatively with the survival expectancy of colon cancer patients.

  12. Glucagon-like peptide 2 dose-dependently activates intestinal cell survival and proliferation in neonatal piglets

    DEFF Research Database (Denmark)

    Burrin, Douglas G; Stoll, Barbara; Guan, Xinfu

    2005-01-01

    saline or GLP-2 at three rates (2.5, 5.0, and 10.0 nmol.kg(-1).d(-1)) for 7 d. Plasma GLP-2 concentrations ranged from 177 +/- 27 to 692 +/- 85 pM in the low- and high-infusion groups, respectively. GLP-2 infusion dose-dependently increased small intestinal weight, DNA and protein content, and villus...... of caspase-3 and -6 and active caspase-3 abundance decreased, yet procaspase-3 abundance increased markedly with increasing infusion rate and plasma concentration of GLP-2. The GLP-2-dose-dependent suppression of intestinal apoptosis and caspase-3 activity was associated with increased protein kinase B...... is concentration dependent at physiological GLP-2 concentrations; however, induction of cell proliferation and protein synthesis is a pharmacological response. Moreover, we show that GLP-2 stimulates intestinal cell survival and proliferation in association with induction of protein kinase B and glycogen...

  13. Histone demethylase JMJD2B is required for tumor cell proliferation and survival and is overexpressed in gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wenjuan; Zhao, Li; Zang, Wen; Liu, Zhifang; Chen, Long; Liu, Tiantian [Department of Microbiology/Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, 44 Wenhua Xi Road, Jinan 250012 (China); Xu, Dawei, E-mail: Dawei.Xu@ki.se [Department of Microbiology/Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, 44 Wenhua Xi Road, Jinan 250012 (China); Department of Medicine, Division of Hematology, Karolinska University Hospital, Solna and Karolinska Institutet, Stockholm (Sweden); Jia, Jihui, E-mail: jiajihui@sdu.edu.cn [Department of Microbiology/Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, 44 Wenhua Xi Road, Jinan 250012 (China)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer JMJD2B is required for cell proliferation and in vivo tumorigenesis. Black-Right-Pointing-Pointer JMJD2B depletion induces apoptosis and/or cell cycle arrest. Black-Right-Pointing-Pointer JMJD2B depletion activates DNA damage response and enhances p53 stabilization. Black-Right-Pointing-Pointer JMJD2B is overexpressed in human primary gastric cancer. -- Abstract: Epigenetic alterations such as aberrant expression of histone-modifying enzymes have been implicated in tumorigenesis. Jumonji domain containing 2B (JMJD2B) is a newly identified histone demethylase that regulates chromatin structure or gene expression by removing methyl residues from trimethylated lysine 9 on histone H3. Recent observations have shown oncogenic activity of JMJD2B. We explored the functional role of JMJD2B in cancer cell proliferation, survival and tumorigenesis, and determined its expression profile in gastric cancer. Knocking down JMJD2B expression by small interfering RNA (siRNA) in gastric and other cancer cells inhibited cell proliferation and/or induced apoptosis and elevated the expression of p53 and p21{sup CIP1} proteins. The enhanced p53 expression resulted from activation of the DNA damage response pathway. JMJD2B knockdown markedly suppressed xenograft tumor growth in vivo in mice. Moreover, JMJD2B expression was increased in primary gastric-cancer tissues of humans. Thus, JMJD2B is required for sustained proliferation and survival of tumor cells in vitro and in vivo, and its aberrant expression may contribute to the pathogenesis of gastric cancer.

  14. Peroxisome Proliferator-Activated Receptor (PPAR): Balance for Survival in Parasitic Infections

    OpenAIRE

    Chan, Marion M.; Evans, Kyle W.; Moore, Andrea R.; Dunne Fong

    2010-01-01

    Parasitic infections induce a magnitude of host responses. At the opposite ends of the spectrum are those that ensure the host's needs to eliminate the invaders and to minimize damage to its own tissues. This review analyzes how parasites would manipulate immunity by activating the immunosuppressive nuclear factor, peroxisome proliferator-activated receptors (PPARs) with type 2 cytokines and free fatty acids from arachidonic acid metabolism. PPARs limit the action of type 1 immunity, in w...

  15. Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) promotes lung fibroblast proliferation, survival and differentiation to myofibroblasts.

    Science.gov (United States)

    Hasaneen, Nadia A; Cao, Jian; Pulkoski-Gross, Ashleigh; Zucker, Stanley; Foda, Hussein D

    2016-02-17

    Idiopathic pulmonary fibrosis (IPF) is a chronic progressively fatal disease. Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) is a glycosylated transmembrane protein that induces the expression of some matrix metalloproteinase (MMP) in neighboring stromal cells through direct epithelial-stromal interactions. EMMPRIN is highly expressed in type II alveolar epithelial cells at the edges of the fibrotic areas in IPF lung sections. However, the exact role of EMMPRIN in IPF is unknown. To determine if EMMPRIN contributes to lung fibroblast proliferation, resistance to apoptosis, and differentiation to myofibroblasts, normal Human lung fibroblasts (NHLF) transiently transfected with either EMMPRIN/GFP or GFP were treated with TGF- β1 from 0 to 10 ng/ml for 48 h and examined for cell proliferation (thymidine incorporation), apoptosis (FACS analysis and Cell Death Detection ELISA assay), cell migration (Modified Boyden chamber) and differentiation to myofibroblasts using Western blot for α-smooth actin of cell lysates. The effect of EMMPRIN inhibition on NHLF proliferation, apoptosis, migration and differentiation to myofibroblasts after TGF- β1 treatment was examined using EMMPRIN blocking antibody. We examined the mechanism by which EMMPRIN induces its effects on fibroblasts by studying the β-catenin/canonical Wnt signaling pathway using Wnt luciferase reporter assays and Western blot for total and phosphorylated β-catenin. Human lung fibroblasts overexpressing EMMPRIN had a significant increase in cell proliferation and migration compared to control fibroblasts. Furthermore, EMMPRIN promoted lung fibroblasts resistance to apoptosis. Lung fibroblasts overexpressing EMMPRIN showed a significantly increased expression of α- smooth muscle actin, a marker of differentiation to myofibroblasts compared to control cells. TGF-β1 increased the expression of EMMPRIN in lung fibroblasts in a dose-dependent manner. Attenuation of EMMPRIN expression with the use of an

  16. Tenovin-6 inhibits proliferation and survival of diffuse large B-cell lymphoma cells by blocking autophagy.

    Science.gov (United States)

    Yuan, Hongfeng; He, Meilan; Cheng, Fan; Bai, Rosemary; da Silva, Suzane Ramos; Aguiar, Ricardo C T; Gao, Shou-Jiang

    2017-02-28

    Diffuse large B-cell lymphoma (DLBCL) is one of the most aggressive non-Hodgkin lymphomas. It is curable but one-third of cases are refractory to therapy or relapse after initial response highlighting the urgent need for developing novel therapeutic approaches. Targeting sirtuins, particularly SIRT1 by genetic approaches or using pharmaceutical inhibitor tenovin-6, has shown promising therapeutic potential in various hematopoietic malignancies. However, it remains unknown whether these approaches are effective for DLBCL. In this study, we have found that tenovin-6 potently inhibits the proliferation and survival of DLBCL cells. Surprisingly, specific knockdown of SIRT1/2/3 has no effect on DLBCL. Mechanistically, tenovin-6 increases the level of microtubule-associated protein 1 light chain 3B (LC3B)-II in a SIRT1/2/3- and p53-independent manner in DLBCL cell lines. Tenovin-6-mediated increase of LC3B-II is through inhibition of classical autophagy pathway. Furthermore, inhibition of the autophagy pathway by using other inhibitors or by knocking down key genes in the pathway impairs cell proliferation and survival of DLBCL cells. These results indicate that targeting the autophagic pathway could be a novel therapeutic strategy for DLBCL and that precaution should be taken to interpret data where tenovin-6 was used as an inhibitor of sirtuins.

  17. microRNA-100 targets SMRT/NCOR2, reduces proliferation, and improves survival in glioblastoma animal models.

    Directory of Open Access Journals (Sweden)

    Bahauddeen M Alrfaei

    Full Text Available Glioblastoma (GBM is the most frequently diagnosed malignant human glioma, and current median patient survival is less than two years despite maximal surgery followed by temozolomide chemoradiation therapies. Novel microRNA-related therapies are now being developed for cancers such as GBM. Differential microRNA expression profiling revealed that miR-100 expression is down-regulated in GBM compared to normal controls. We report that miR-100 expression reduces GBM tumorigenicity. In vitro, four GBM lines (U87, U251, 22T, and 33T demonstrated reduced proliferation 24 hours after transient miR100 overexpression via transfection. miR-100 triggered cell death an average 70% more than scrambled miR controls 24 hours after transient transfection (p < 0.01. miR-100 targeted inhibition of the "silencing mediator of retinoid or thyroid hormone receptor-2" (SMRT/NCOR2 gene was confirmed via reporter assays. Ki67 proliferation index was decreased 40% in tumor xenografts generated from stable miR-100 transfected GBM lines versus controls (p < 0.01. Furthermore, treatment of tumor xenografts with a single pre-mir-100 injection (60 pmol significantly extended survival of mice bearing intracranial GBM xenografts 25% more than scrambled controls (p < 0.01; n=8. These studies establish miR-100's effect on tumor GBM growth, and suggest clinical potential for microRNA-related GBM therapy.

  18. microRNA-100 Targets SMRT/NCOR2, Reduces Proliferation, and Improves Survival in Glioblastoma Animal Models

    Science.gov (United States)

    Alrfaei, Bahauddeen M.; Vemuganti, Raghu; Kuo, John S.

    2013-01-01

    Glioblastoma (GBM) is the most frequently diagnosed malignant human glioma, and current median patient survival is less than two years despite maximal surgery followed by temozolomide chemoradiation therapies. Novel microRNA-related therapies are now being developed for cancers such as GBM. Differential microRNA expression profiling revealed that miR-100 expression is down-regulated in GBM compared to normal controls. We report that miR-100 expression reduces GBM tumorigenicity. In vitro, four GBM lines (U87, U251, 22T, and 33T) demonstrated reduced proliferation 24 hours after transient miR100 overexpression via transfection. miR-100 triggered cell death an average 70% more than scrambled miR controls 24 hours after transient transfection (p SMRT/NCOR2) gene was confirmed via reporter assays. Ki67 proliferation index was decreased 40% in tumor xenografts generated from stable miR-100 transfected GBM lines versus controls (p < 0.01). Furthermore, treatment of tumor xenografts with a single pre-mir-100 injection (60 pmol) significantly extended survival of mice bearing intracranial GBM xenografts 25% more than scrambled controls (p < 0.01; n=8). These studies establish miR-100’s effect on tumor GBM growth, and suggest clinical potential for microRNA-related GBM therapy. PMID:24244722

  19. Ex Vivo Expanded Human NK Cells Survive and Proliferate in Humanized Mice with Autologous Human Immune Cells.

    Science.gov (United States)

    Vahedi, Fatemeh; Nham, Tina; Poznanski, Sophie M; Chew, Marianne V; Shenouda, Mira M; Lee, Dean; Ashkar, Ali A

    2017-09-21

    Adoptive immune cell therapy is emerging as a promising immunotherapy for cancer. Particularly, the adoptive transfer of NK cells has garnered attention due to their natural cytotoxicity against tumor cells and safety upon adoptive transfer to patients. Although strategies exist to efficiently generate large quantities of expanded NK cells ex vivo, it remains unknown whether these expanded NK cells can persist and/or proliferate in vivo in the absence of exogenous human cytokines. Here, we have examined the adoptive transfer of ex vivo expanded human cord blood-derived NK cells into humanized mice reconstituted with autologous human cord blood immune cells. We report that ex vivo expanded NK cells are able to survive and possibly proliferate in vivo in humanized mice without exogenous cytokine administration, but not in control mice that lack human immune cells. These findings demonstrate that the presence of autologous human immune cells supports the in vivo survival of ex vivo expanded human NK cells. These results support the application of ex vivo expanded NK cells in cancer immunotherapy and provide a translational humanized mouse model to test the lifespan, safety, and functionality of adoptively transferred cells in the presence of autologous human immune cells prior to clinical use.

  20. Induction of cell proliferation and survival genes by estradiol-repressed microRNAs in breast cancer cells

    Directory of Open Access Journals (Sweden)

    Yu Xinfeng

    2012-01-01

    Full Text Available Abstract Background In estrogen responsive MCF-7 cells, estradiol (E2 binding to ERα leads to transcriptional regulation of genes involved in the control of cell proliferation and survival. MicroRNAs (miRNAs have emerged as key post-transcriptional regulators of gene expression. The aim of this study was to explore whether miRNAs were involved in hormonally regulated expression of estrogen responsive genes. Methods Western blot and QPCR were used to determine the expression of estrogen responsive genes and miRNAs respectively. Target gene expression regulated by miRNAs was validated by luciferase reporter assays and transfection of miRNA mimics or inhibitors. Cell proliferation was evaluated by MTS assay. Results E2 significantly induced bcl-2, cyclin D1 and survivin expression by suppressing the levels of a panel of miRNAs (miR-16, miR-143, miR-203 in MCF-7 cells. MiRNA transfection and luciferase assay confirmed that bcl-2 was regulated by miR-16 and miR-143, cyclinD1 was modulated by miR-16. Importantly, survivin was found to be targeted by miR-16, miR-143, miR-203. The regulatory effect of E2 can be either abrogated by anti-estrogen ICI 182, 780 and raloxifene pretreatment, or impaired by ERα siRNA, indicating the regulation is dependent on ERα. In order to investigate the functional significance of these miRNAs in estrogen responsive cells, miRNAs mimics were transfected into MCF-7 cells. It revealed that overexpression of these miRNAs significantly inhibited E2-induced cell proliferation. Further study of the expression of the miRNAs indicated that miR-16, miR-143 and miR-203 were highly expressed in triple positive breast cancer tissues, suggesting a potential tumor suppressing effect of these miRNAs in ER positive breast cancer. Conclusions These results demonstrate that E2 induces bcl-2, cyclin D1 and survivin by orchestrating the coordinate downregulation of a panel of miRNAs. In turn, the miRNAs manifest growth suppressive effects

  1. Hepatocyte growth factor modulates in vitro survival and proliferation of germ cells during postnatal testis development.

    Science.gov (United States)

    Catizone, A; Ricci, G; Del Bravo, J; Galdieri, M

    2006-04-01

    The hepatocyte growth factor (HGF) is a pleiotropic cytokine that influences mitogenesis, motility and differentiation of many different cell types by its tyrosine kinase receptor c-Met. We previously demonstrated that the c-Met/HGF system is present and functionally active during postnatal testis development. We found also that spermatozoa express c-Met and that HGF has a positive effect on the maintenance of sperm motility. In the present paper, we extend our study on the germ cells at different stages of differentiation during the postnatal development of the testis. We demonstrate that c-met is present in rat spermatogonia, pachytene spermatocytes and round spermatids and that HGF significantly increases spermatogonial proliferation in 8- to 10-day-old pre-pubertal rats. At this age HGF does not affect Sertoli cells and peritubular myoid cells proliferation. In addition, we studied the effect of the factor on germ cell apoptosis and we show that HGF prevents the germ cell apoptotic process. We also studied the effect of HGF on 18- to 20-day-old and 28- to 30-day-old rat testes. At these ages also the factor significantly increases germ cell duplication and decreases the number of apoptotic cells. However, the effect on programmed cell death is higher in the 8- to 10-day-old rats and declines in the older animals. In conclusion, we report that rat germ cells (spermatogonia, pachytene spermatocytes and round spermatids) express c-met and that HGF modulates germ cell proliferating activity and apoptosis in vitro. These data indicate that the c-Met/HGF system is involved in male germ cell homeostasis and, consequently, has a role in male fertility.

  2. Long-term potentiation promotes proliferation/survival and neuronal differentiation of neural stem/progenitor cells.

    Directory of Open Access Journals (Sweden)

    Taesup Cho

    Full Text Available Neural stem cell (NSC replacement therapy is considered a promising cell replacement therapy for various neurodegenerative diseases. However, the low rate of NSC survival and neurogenesis currently limits its clinical potential. Here, we examined if hippocampal long-term potentiation (LTP, one of the most well characterized forms of synaptic plasticity, promotes neurogenesis by facilitating proliferation/survival and neuronal differentiation of NSCs. We found that the induction of hippocampal LTP significantly facilitates proliferation/survival and neuronal differentiation of both endogenous neural progenitor cells (NPCs and exogenously transplanted NSCs in the hippocampus in rats. These effects were eliminated by preventing LTP induction by pharmacological blockade of the N-methyl-D-aspartate glutamate receptor (NMDAR via systemic application of the receptor antagonist, 3-[(R-2-carboxypiperazin-4-yl]-propyl-1-phosphonic acid (CPP. Moreover, using a NPC-neuron co-culture system, we were able to demonstrate that the LTP-promoted NPC neurogenesis is at least in part mediated by a LTP-increased neuronal release of brain-derived neurotrophic factor (BDNF and its consequent activation of tropomysosin receptor kinase B (TrkB receptors on NSCs. Our results indicate that LTP promotes the neurogenesis of both endogenous and exogenously transplanted NSCs in the brain. The study suggests that pre-conditioning of the host brain receiving area with a LTP-inducing deep brain stimulation protocol prior to NSC transplantation may increase the likelihood of success of using NSC transplantation as an effective cell therapy for various neurodegenerative diseases.

  3. Prostaglandin receptor EP3 regulates cell proliferation and migration with impact on survival of endometrial cancer patients.

    Science.gov (United States)

    Zhu, Junyan; Trillsch, Fabian; Mayr, Doris; Kuhn, Christina; Rahmeh, Martina; Hofmann, Simone; Vogel, Marianne; Mahner, Sven; Jeschke, Udo; von Schönfeldt, Viktoria

    2018-01-02

    Prostaglandin E2 (PGE2) receptor 3 (EP3) regulates tumor cell proliferation, migration, and invasion in numerous cancers. The role of EP3 as a prognostic biomarker in endometrial cancer remains unclear. The primary aim of this study was to analyze the prognostic significance of EP3 expression in endometrial cancer. We analyzed the EP3 expression of 140 endometrial carcinoma patients by immunohistochemistry. RL95-2 endometrial cancer cell line was chosen from four endometrial cancer cell lines (RL95-2, Ishikawa, HEC-1-A, and HEC-1-B) according to EP3 expression level. Treated with PGE2 and EP3 antagonist, RL95-2 cells were investigated by MTT, BrdU, and wound healing assay for functional assessment of EP3. EP3 staining differed significantly according to WHO tumor grading in both whole cohort (p = 0.01) and the subgroup of endometrioid carcinoma (p = 0.01). Patients with high EP3 expression in their respective tumors had impaired progression-free survival as well as overall survival in both cohorts above. EP3 expression in the overall cohort was identified as an independent prognostic marker for progression-free survival (HR 1.014, 95%CI 1.003-1.024, p = 0.01) when adjusted for age, stage, grading, and recurrence. Treatment with EP3 antagonists induced upregulation of estrogen receptor β and decreased activity of Ras and led to attenuated proliferation and migration of RL95-2 cells. EP3 seems to play a crucial role in endometrial cancer progression. In the context of limited systemic treatment options for endometrial cancer, this explorative analysis identifies EP3 as a potential target for diagnostic workup and therapy.

  4. Muscle mitohormesis promotes cellular survival via serine/glycine pathway flux

    NARCIS (Netherlands)

    Ost, M.; Keipert, S.; Schothorst, van E.M.; Donner, V.; Stelt, van der I.; Kipp, A.; Petzke, K.J.; Jove, M.; Pamplona, R.; Portero-Otin, M.; Keijer, J.; Klaus, S.

    2015-01-01

    Recent studies on mouse and human skeletal muscle (SM) demonstrated the important link between mitochondrial function and the cellular metabolic adaptation. To identify key compensatory molecular mechanisms in response to chronic mitochondrial distress, we analyzed mice with ectopic SM respiratory

  5. Macrophages improve survival, proliferation and migration of engrafted myogenic precursor cells into MDX skeletal muscle.

    Directory of Open Access Journals (Sweden)

    Pierre-François Lesault

    Full Text Available Transplantation of muscle precursor cells is of therapeutic interest for focal skeletal muscular diseases. However, major limitations of cell transplantation are the poor survival, expansion and migration of the injected cells. The massive and early death of transplanted myoblasts is not fully understood although several mechanisms have been suggested. Various attempts have been made to improve their survival or migration. Taking into account that muscle regeneration is associated with the presence of macrophages, which are helpful in repairing the muscle by both cleansing the debris and deliver trophic cues to myoblasts in a sequential way, we attempted in the present work to improve myoblast transplantation by coinjecting macrophages. The present data showed that in the 5 days following the transplantation, macrophages efficiently improved: i myoblast survival by limiting their massive death, ii myoblast expansion within the tissue and iii myoblast migration in the dystrophic muscle. This was confirmed by in vitro analyses showing that macrophages stimulated myoblast adhesion and migration. As a result, myoblast contribution to regenerating host myofibres was increased by macrophages one month after transplantation. Altogether, these data demonstrate that macrophages are beneficial during the early steps of myoblast transplantation into skeletal muscle, showing that coinjecting these stromal cells may be used as a helper to improve the efficiency of parenchymal cell engraftment.

  6. Plasma Rich in Growth Factors Induces Cell Proliferation, Migration, Differentiation, and Cell Survival of Adipose-Derived Stem Cells

    Directory of Open Access Journals (Sweden)

    Maravillas Mellado-López

    2017-01-01

    Full Text Available Adipose-derived stem cells (ASCs are a promising therapeutic alternative for tissue repair in various clinical applications. However, restrictive cell survival, differential tissue integration, and undirected cell differentiation after transplantation in a hostile microenvironment are complications that require refinement. Plasma rich in growth factors (PRGF from platelet-rich plasma favors human and canine ASC survival, proliferation, and delaying human ASC senescence and autophagocytosis in comparison with serum-containing cultures. In addition, canine and human-derived ASCs efficiently differentiate into osteocytes, adipocytes, or chondrocytes in the presence of PRGF. PRGF treatment induces phosphorylation of AKT preventing ASC death induced by lethal concentrations of hydrogen peroxide. Indeed, AKT inhibition abolished the PRGF apoptosis prevention in ASC exposed to 100 μM of hydrogen peroxide. Here, we show that canine ASCs respond to PRGF stimulus similarly to the human cells regarding cell survival and differentiation postulating the use of dogs as a suitable translational model. Overall, PRGF would be employed as a serum substitute for mesenchymal stem cell amplification to improve cell differentiation and as a preconditioning agent to prevent oxidative cell death.

  7. Peroxisome Proliferator-Activated Receptor (PPAR: Balance for Survival in Parasitic Infections

    Directory of Open Access Journals (Sweden)

    Marion M. Chan

    2010-01-01

    Full Text Available Parasitic infections induce a magnitude of host responses. At the opposite ends of the spectrum are those that ensure the host's needs to eliminate the invaders and to minimize damage to its own tissues. This review analyzes how parasites would manipulate immunity by activating the immunosuppressive nuclear factor, peroxisome proliferator-activated receptors (PPARs with type 2 cytokines and free fatty acids from arachidonic acid metabolism. PPARs limit the action of type 1 immunity, in which classically activated macrophages act through the production of proinflammatory signals, to spare the parasites. They also favor the development of alternately activated macrophages which control inflammation so the host would not be destroyed. Possibly, the nuclear factors hold a pivotal role in the establishment of chronic infection by delicately balancing the pro- and anti-inflammatory signaling mechanisms and their ligands may be used as combination therapeutics to limit host pathology.

  8. Expression of exogenous LIN28 contributes to proliferation and survival of mouse primary cortical neurons in vitro.

    Science.gov (United States)

    Bhuiyan, M I H; Lee, J-H; Kim, S Y; Cho, K-O

    2013-09-17

    LIN28, an RNA-binding protein, is known to be involved in the regulation of many cellular processes, such as embryonic stem cell proliferation, cell fate succession, developmental timing, and oncogenesis. In this study, we investigated the effect of constitutively expressing exogenous LIN28 on neuronal cell proliferation and viability in vitro. Plasmids containing LIN28-green fluorescent protein (GFP) or GFP were introduced into the embryonic mouse brains at E14.5 by in utero electroporation. Two days after electroporation, embryonic cortices were harvested and cultured. It was found that transfected cells stably overexpressed LIN28 in vitro. Viability curve from live cell imaging showed that the number of GFP-expressing cells decreased over time in line with naive primary cortical neurons. In contrast, the number of LIN28-GFP-overexpressing neurons initially increased and remained high at later time-points in culture than GFP-expressing cells. Double immunofluorescence showed that at an early time in culture, the number of Ki-67/GFP double-positive cells was higher in the LIN28-GFP group than that of controls. Moreover, there were significantly lower numbers of condensed nuclei/GFP- and cleaved caspase-3/GFP-positive cells in the LIN28-GFP groups compared to control GFP. Furthermore, it was confirmed that the LIN28-GFP-expressing cells at days in vitro (DIV)13 were neuronal nuclei (NeuN)-positive mature neurons. Finally, the expression of insulin-like growth factor 2 (IGF-2) was induced in LIN28-expressing primary cortical neurons, which was not detected in controls. Taken together, our results indicate that the expression of exogenous LIN28 can promote the proliferation of neural progenitor cells and exert prosurvival effect on primary cortical neurons by inhibiting caspase-dependent apoptosis, possibly via upregulation of IGF-2. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. Sigma-1 receptor chaperone at the ER-mitochondrion interface mediates the mitochondrion-ER-nucleus signaling for cellular survival.

    Science.gov (United States)

    Mori, Tomohisa; Hayashi, Teruo; Hayashi, Eri; Su, Tsung-Ping

    2013-01-01

    The membrane of the endoplasmic reticulum (ER) of a cell forms contacts directly with mitochondria whereby the contact is referred to as the mitochondrion-associated ER membrane or the MAM. Here we found that the MAM regulates cellular survival via an MAM-residing ER chaperone the sigma-1 receptor (Sig-1R) in that the Sig-1R chaperones the ER stress sensor IRE1 to facilitate inter-organelle signaling for survival. IRE1 is found in this study to be enriched at the MAM in CHO cells. We found that IRE1 is stabilized at the MAM by Sig-1Rs when cells are under ER stress. Sig-1Rs stabilize IRE1 and thus allow for conformationally correct IRE1 to dimerize into the long-lasting, activated endonuclease. The IRE1 at the MAM also responds to reactive oxygen species derived from mitochondria. Therefore, the ER-mitochondrion interface serves as an important subcellular entity in the regulation of cellular survival by enhancing the stress-responding signaling between mitochondria, ER, and nucleus.

  10. Krüppel-like factor 5 is essential for proliferation and survival of mouse intestinal epithelial stem cells

    Directory of Open Access Journals (Sweden)

    Mandayam O. Nandan

    2015-01-01

    Full Text Available Krüppel-like factor 5 (KLF5 is a pro-proliferative transcription factor that is expressed in dividing epithelial cells of the intestinal crypt. Leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5 has been identified as a stem cell marker in both small intestinal and colonic epithelial cells. To determine whether KLF5 regulates proliferation of intestinal stem cells, we investigated the effects of Klf5 deletion specifically from the intestinal stem cells in adult mice. Mice with inducible intestinal stem cell-specific deletion of Klf5 (Lgr5-Klf5fl/fl were injected with tamoxifen for 5 consecutive days to induce Lgr5-driven Cre expression. Intestinal and colonic tissues were examined by immunohistochemistry at various time points up to 112 days following start of tamoxifen treatment. Klf5 is co-localized in the crypt-based columnar (CBC cells that express Lgr5. By 11 days following the start of tamoxifen treatment, Lgr5-positive crypts from which Klf5 was deleted exhibited a loss of proliferation that was accompanied by an increase in apoptosis. Beginning at 14 days following the start of tamoxifen treatment, both Klf5 expression and proliferation were re-established in the transit-amplifying epithelial cells but not in the Lgr5-positive CBC cells. By 112 days post-treatment, up to 90% of the Lgr5-positive cells from which Klf5 was deleted were lost from the intestinal crypts. These results indicate a critical role for KLF5 in the survival and maintenance of intestinal stem cells.

  11. Anti-MHC Class I Antibody Activation of Proliferation and Survival Signaling in Murine Cardiac Allografts1

    Science.gov (United States)

    Jindra, Peter T.; Hsueh, Aileen; Hong, Longshen; Gjertson, David; Shen, Xiu-Da; Gao, Feng; Dang, Julie; Mischel, Paul S.; Baldwin, William M.; Fishbein, Michael C.; Kupiec-Weglinski, Jerzy W.; Reed, Elaine F.

    2013-01-01

    Anti-MHC class I alloantibodies have been implicated in the process of acute and chronic rejection because these Abs can bind to endothelial cells and transduce signals leading to the activation of cell survival and proliferation pathways. To characterize the role of the MHC class I-signaling pathway in the pathogenesis of Ab-mediated rejection, we developed a mouse vascularized heterotopic cardiac allograft model in which B6.RAG1 KO hosts (H-2Kb/Db) received a fully MHC-incompatible BALB/c (H-2Kd/Dd) heart transplant and were passively transfused with anti-donor MHC class I Ab. We demonstrate that cardiac allografts of mice treated with anti-MHC class I Abs show characteristic features of Ab-mediated rejection including microvascular changes accompanied by C4d deposition. Phosphoproteomic analysis of signaling molecules involved in the MHC class I cell proliferation and survival pathways were elevated in anti-class I-treated mice compared with the isotype control-treated group. Pairwise correlations, hierarchical clustering, and multidimensional scaling algorithms were used to dissect the class I-signaling pathway in vivo. Treatment with anti-H-2Kd Ab was highly correlated with the activation of Akt and p70S6Kinase (S6K). When measuring distance as a marker of interrelatedness, multidimensional scaling analysis revealed a close association between members of the mammalian target of rapamycin pathway including mammalian target of rapamycin, S6K, and S6 ribosomal protein. These results provide the first analysis of the interrelationships between these signaling molecules in vivo that reflects our knowledge of the signaling pathway derived from in vitro experiments. PMID:18250428

  12. ICT1 predicts a poor survival and correlated with cell proliferation in diffuse large B-cell lymphoma.

    Science.gov (United States)

    Xie, Wenjun; Wu, Meijuan; Fu, Tianhong; Li, Xiaohong; Wang, Zhaoming; Hu, Yongxian; Zhu, Liyan; Zhang, Gu

    2017-09-05

    Immature colon carcinoma transcript-1 (ICT1) is a crucial member of the large mitoribosomal subunit in mitochondrial ribosome, which has been shown to be closely related to tumorigenesis. Its expression and function in human diffuse large B-cell lymphoma (DLBCL), however, remained elusive. In this study, analysis of public available Oncomine database suggested that the expression levels of ICT1 mRNA was significantly upregulated in DLBCL tissues. Consistently, we described ICT1 was remarkably upregulated in fresh DLBCL samples compared with the corresponding normal tissues using quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and Western blotting. Moreover, ICT1 overexpression was associated with the poor overall survival (OS) of DLBCL patients. Finally, we used DLBCL cell lines to further probe the potential mechanisms, and found shRNA-mediated knockdown of ICT1 significantly suppressed DLBCL cell proliferation, induced cell cycle arrest at G0/G1 phase and apoptosis in vitro. Further verification showed that inhibition of ICT1 gene expression caused the upregulation of the p21, Bad and caspase-3, and downregulation of PCNA, Survivin, CDK4, CDK6 and Cyclin D1. Taken together, this study suggested that ICT1 may play an oncogenic role in human DLBCL by promoting cell proliferation and it might be a biomarker of unfavorable prognosis in DLBCL patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Serratia marcescens Is Able to Survive and Proliferate in Autophagic-Like Vacuoles inside Non-Phagocytic Cells

    Science.gov (United States)

    Colombo, María Isabel; García Véscovi, Eleonora

    2011-01-01

    Serratia marcescens is an opportunistic human pathogen that represents a growing problem for public health, particularly in hospitalized or immunocompromised patients. However, little is known about factors and mechanisms that contribute to S. marcescens pathogenesis within its host. In this work, we explore the invasion process of this opportunistic pathogen to epithelial cells. We demonstrate that once internalized, Serratia is able not only to persist but also to multiply inside a large membrane-bound compartment. This structure displays autophagic-like features, acquiring LC3 and Rab7, markers described to be recruited throughout the progression of antibacterial autophagy. The majority of the autophagic-like vacuoles in which Serratia resides and proliferates are non-acidic and have no degradative properties, indicating that the bacteria are capable to either delay or prevent fusion with lysosomal compartments, altering the expected progression of autophagosome maturation. In addition, our results demonstrate that Serratia triggers a non-canonical autophagic process before internalization. These findings reveal that S. marcescens is able to manipulate the autophagic traffic, generating a suitable niche for survival and proliferation inside the host cell. PMID:21901159

  14. Nerve Regeneration Potential of Protocatechuic Acid in RSC96 Schwann Cells by Induction of Cellular Proliferation and Migration through IGF-IR-PI3K-Akt Signaling.

    Science.gov (United States)

    Ju, Da-Tong; Liao, Hung-En; Shibu, Marthandam Asokan; Ho, Tsung-Jung; Padma, Viswanadha Vijaya; Tsai, Fuu-Jen; Chung, Li-Chin; Day, Cecilia Hsuan; Lin, Chien-Chung; Huang, Chih-Yang

    2015-12-31

    Peripheral nerve injuries, caused by accidental trauma, acute compression or surgery, often result in temporary or life-long neuronal dysfunctions and inflict great economic or social burdens on the patients. Nerve cell proliferation is an essential process to restore injured nerves of adults. Schwann cells play a crucial role in endogenous repair of peripheral nerves due to their ability to proliferate, migrate and provide trophic support to axons via expression of various neurotrophic factors, such as the nerve growth factor (NGF), especially after nerve injury. Protocatechuic acid (PCA) is a dihydroxybenzoic acid, a type of phenolic acid, isolated from the kernels of Alpinia oxyphylla Miq (AOF), a traditional Chinese herbal medicine the fruits of which are widely used as a tonic, aphrodisiac, anti-salivation and anti-diarrheatic. This study investigated the molecular mechanisms by which PCA induces Schwann cell proliferation by activating IGF-IR-PI3K-Akt pathway. Treatment with PCA induces phosphorylation of the insulin-like growth factor-I (IGF-I)-mediated phosphatidylinositol 3 kinase/serine - threonine kinase (PI3K/Akt) pathway, and activates expression of cell nuclear antigen (PCNA) in a dose-dependent manner. Cell cycle analysis after 18 h of treatment showed that proliferation of the RSC96 cells was enhanced by PCA treatment. The PCA induced proliferation was accompanied by modulation in the expressions of cell cycle proteins cyclin D1, cyclin E and cyclin A. Knockdown of PI3K using small interfering RNA (siRNA) and inhibition of IGF-IR receptor resulted in the reduction in cell survival proteins. The results collectively showed that PCA treatment promoted cell proliferation and cell survival via IGF-I signaling.

  15. The Role of Heme and Reactive Oxygen Species in Proliferation and Survival of Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Marcia Cristina Paes

    2011-01-01

    Full Text Available Trypanosoma cruzi, the protozoan responsible for Chagas disease, has a complex life cycle comprehending two distinct hosts and a series of morphological and functional transformations. Hemoglobin degradation inside the insect vector releases high amounts of heme, and this molecule is known to exert a number of physiological functions. Moreover, the absence of its complete biosynthetic pathway in T. cruzi indicates heme as an essential molecule for this trypanosomatid survival. Within the hosts, T. cruzi has to cope with sudden environmental changes especially in the redox status and heme is able to increase the basal production of reactive oxygen species (ROS which can be also produced as byproducts of the parasite aerobic metabolism. In this regard, ROS sensing is likely to be an important mechanism for the adaptation and interaction of these organisms with their hosts. In this paper we discuss the main features of heme and ROS susceptibility in T. cruzi biology.

  16. An overview of colorimetric assay methods used to assess survival or proliferation of mammalian cells.

    Science.gov (United States)

    Vega-Avila, Elisa; Pugsley, Michael K

    2011-01-01

    The aim of this review is to briefly describe some colorimetric methods that are commonly used to evaluate a new chemical entity (NCE) on cell cultures in non-clinical oncology discovery research. These methods have the distinct advantage over other techniques in that they can be applied and used in a cell monolayer or a suspension culture. Both protein assay determination and cell viability assays may be conducted using these culture systems. The viability of cell cultures is routinely assessed by utilizing the metabolic capacity of cells which biochemically convert chemicals (usually color dyes) which can then be conveniently measured at specific wavelengths using a multi-well plate reader. Resazurin (Alamar Blue) is an example of one of these metabolically active compounds. Resazurin is a nontoxic dye that can also be used to measure migration and cellular invasion without resorting to sacrifice of the cells during the test procedure. Another is 5-bromo-2-deoxyuridine (bromodeoxyuridine or BrdU) which is a thymidine analog that incorporates into the DNA of dividing cells during the S-phase of the cell cycle. We will also discuss the colorimetric version of the traditional 3H-thymidine incorporation and immunoenzymatic assay used to measure DNA synthesis and its application to discovery research.

  17. Andrographolide Suppresses MV4-11 Cell Proliferation through the Inhibition of FLT3 Signaling, Fatty Acid Synthesis and Cellular Iron Uptake

    Directory of Open Access Journals (Sweden)

    Xiao Chen

    2017-08-01

    Full Text Available Background: Andrographolide (ADR, the main active component of Andrographis paniculata, displays anticancer activity in various cancer cell lines, among which leukemia cell lines exhibit the highest sensitivity to ADR. In particular, ADR was also reported to have reduced drug resistance in multidrug resistant cell lines. However, the mechanism of action (MOA of ADR’s anticancer and anti-drug-resistance activities remain elusive. Methods: In this study, we used the MV4-11 cell line, a FLT3 positive acute myeloid leukemia (AML cell line that displays multidrug resistance, as our experimental system. We first evaluated the effect of ADR on MV4-11 cell proliferation. Then, a quantitative proteomics approach was applied to identify differentially expressed proteins in ADR-treated MV4-11 cells. Finally, cellular processes and signal pathways affected by ADR in MV4-11 cell were predicted with proteomic analysis and validated with in vitro assays. Results: ADR inhibits MV4-11 cell proliferation in a dose- and time-dependent manner. With a proteomic approach, we discovered that ADR inhibited fatty acid synthesis, cellular iron uptake and FLT3 signaling pathway in MV4-11 cells. Conclusions: ADR inhibits MV4-11 cell proliferation through inhibition of fatty acid synthesis, iron uptake and protein synthesis. Furthermore, ADR reduces drug resistance by blocking FLT3 signaling.

  18. Merlin, a "magic" linker between extracellular cues and intracellular signaling pathways that regulate cell motility, proliferation, and survival.

    Science.gov (United States)

    Stamenkovic, Ivan; Yu, Qin

    2010-09-01

    Genetic alterations of neurofibromatosis type 2 (NF2) gene lead to the development of schwannomas, meningiomas, and ependymomas. Mutations of NF2 gene were also found in thyroid cancer, mesothelioma, and melanoma, suggesting that it functions as a tumor suppressor in a wide spectrum of cells. The product of NF2 gene is merlin (moesin-ezrin-radixin-like protein), a member of the Band 4.1 superfamily proteins. Merlin shares significant sequence homology with the ERM (Ezrin-Radixin-Moesin) family proteins and serves as a linker between transmembrane proteins and the actin-cytoskeleton. Merlin is a multifunctional protein and involved in integrating and regulating the extracellular cues and intracellular signaling pathways that control cell fate, shape, proliferation, survival, and motility. Recent studies showed that merlin regulates the cell-cell and cell-matrix adhesions and functions of the cell surface adhesion/extracellular matrix receptors including CD44 and that merlin and CD44 antagonize each other's function and work upstream of the mammalian Hippo signaling pathway. Furthermore, merlin plays important roles in stabilizing the contact inhibition of proliferation and in regulating activities of several receptor tyrosine kinases. Accumulating data also suggested an emerging role of merlin as a negative regulator of growth and progression of several non-NF2 associated cancer types. Together, these recent advances have improved our basic understanding about merlin function, its regulation, and the major signaling pathways regulated by merlin and provided the foundation for future translation of these findings into the clinic for patients bearing the cancers in which merlin function and/or its downstream signaling pathways are impaired or altered.

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

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seong-Su, E-mail: seong-su-han@uiowa.edu [Division of Pediatric Hematology-Oncology, University of Iowa Carver College of Medicine, Iowa City, IA (United States); Han, Sangwoo [Health and Human Physiology, University of Iowa Carver College of Medicine, Iowa City, IA (United States); Kamberos, Natalie L. [Division of Pediatric Hematology-Oncology, University of Iowa Carver College of Medicine, Iowa City, IA (United States)

    2014-09-26

    Highlights: • PL inhibits the proliferation of B-ALL cell lines irrespective of GC-resistance. • PL selectively kills B-ALL cells by increasing ROS, but not normal counterpart. • PL does not sensitize majority of B-ALL cells to DEX. • PL represses the network of constitutively activated TFs and modulates their target genes. • PL may serve as a new therapeutic molecule for GC-resistant B-ALL. - Abstract: Piperlongumine (PL), a pepper plant alkaloid from Piper longum, has anti-inflammatory and anti-cancer properties. PL selectively kills both solid and hematologic cancer cells, but not normal counterparts. Here we evaluated the effect of PL on the proliferation and survival of B-cell acute lymphoblastic leukemia (B-ALL), including glucocorticoid (GC)-resistant B-ALL. Regardless of GC-resistance, PL inhibited the proliferation of all B-ALL cell lines, but not normal B cells, in a dose- and time-dependent manner and induced apoptosis via elevation of ROS. Interestingly, PL did not sensitize most of B-ALL cell lines to dexamethasone (DEX). Only UoC-B1 exhibited a weak synergistic effect between PL and DEX. All B-ALL cell lines tested exhibited constitutive activation of multiple transcription factors (TFs), including AP-1, MYC, NF-κB, SP1, STAT1, STAT3, STAT6 and YY1. Treatment of the B-ALL cells with PL significantly downregulated these TFs and modulated their target genes. While activation of AURKB, BIRC5, E2F1, and MYB mRNA levels were significantly downregulated by PL, but SOX4 and XBP levels were increased by PL. Intriguingly, PL also increased the expression of p21 in B-ALL cells through a p53-independent mechanism. Given that these TFs and their target genes play critical roles in a variety of hematological malignancies, our findings provide a strong preclinical rationale for considering PL as a new therapeutic agent for the treatment of B-cell malignancies, including B-ALL and GC-resistant B-ALL.

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

    DEFF Research Database (Denmark)

    Brockdorff, J; Nielsen, M; Kaltoft, K

    2000-01-01

    The role of Lck in IL-2-induced proliferation and cell survival is still controversial. Here, we show that the Src family kinase inhibitor, PP1, reduced the IL-2-induced proliferation of human T cells significantly without inhibiting the anti-apoptotic effect of IL-2. As Lck is the only Src family...... kinase activated upon IL-2 stimulation in T cells, this indicates that Lck is involved in IL-2-induced proliferation but not survival. IL-2-induced MAP kinase activation was only slightly inhibited by PP1, suggesting that Lck is not essential for IL-2-induced MAP kinase activation in human T cells. We...... found that an IL-2-sensitive, human mycosis fungoides-derived tumor T cell line is Lck negative, and that the IL-2-induced MAP kinase activation is comparable to non-cancerous T cells, although a little delayed in kinetics. An Lck expressing clone was established by transfecting Lck into mycosis...

  1. Asiatic acid protects against cognitive deficits and reductions in cell proliferation and survival in the rat hippocampus caused by 5-fluorouracil chemotherapy.

    Directory of Open Access Journals (Sweden)

    Pornthip Chaisawang

    Full Text Available The chemotherapy drug, 5-fluorouracil (5-FU, has been reported to cause cognitive impairments in cancer patients. The drug also reduces cell proliferation and survival in the brain. Asiatic acid (AA is a triterpene compound found in Centella asiatica that can protect against reduction of neurogenesis in the hippocampus and memory deficits induced by valproic acid (VPA. In the present study, we investigated the preventive effects of AA on the deficits in spatial working memory and cell proliferation and survival caused by 5-FU chemotherapy in a rat model. Male Sprague Dawley rats received 5-FU (5 i.v. injections, 25 mg/kg on day 8, 11, 14, 17 and 20 of the study. This was co-administered with AA (30 mg/kg, oral gavage tube either 20 days before receiving 5-FU (preventive, after receiving 5-FU (recovery, or for the entire period of the experiment (throughout. Spatial working memory was determined using the novel object location (NOL test and hippocampal cell proliferation and survival of dividing cells were quantified using immunohistochemistry. Rats in the 5-FU alone and recovery groups showed memory deficits in the NOL test and reductions in cell proliferation and cell survival in the subgranular zone (SGZ of the hippocampal dentate gyrus. Rats in the control, AA alone, and both preventive and throughout co-administration groups, however, did not exhibit these characteristics. The results showed that 5-FU chemotherapy impaired memory and reduced cell proliferation and cell survival in the SGZ of the hippocampal dentate gyrus. However, these impairments in the animals receiving 5-FU chemotherapy were restored to control levels when AA was co-administered before and during 5-FU treatment. These data demonstrate that AA can prevent the spatial working memory and hippocampal neurogenesis impairments caused by 5-FU chemotherapy.

  2. Store-Operated Ca2+ Entry Does Not Control Proliferation in Primary Cultures of Human Metastatic Renal Cellular Carcinoma

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    Silvia Dragoni

    2014-01-01

    Full Text Available Store-operated Ca2+ entry (SOCE is activated following depletion of the inositol-1,4,5-trisphosphate (InsP3-sensitive Ca2+ pool to regulate proliferation in immortalized cell lines established from either primary or metastatic lesions. The molecular nature of SOCE may involve both Stim1, which senses Ca2+ levels within the endoplasmic reticulum (ER Ca2+ reservoir, and a number of a Ca2+-permeable channels on the plasma membrane, including Orai1, Orai3, and members of the canonical transient receptor (TRPC1–7 family of ion channels. The present study was undertaken to assess whether SOCE is expressed and controls proliferation in primary cultures isolated from secondary lesions of heavily pretreated metastatic renal cell carcinoma (mRCC patients. SOCE was induced following pharmacological depletion of the ER Ca2+ store, but not by InsP3-dependent Ca2+ release. Metastatic RCC cells express Stim1-2, Orai1–3, and TRPC1–7 transcripts and proteins. In these cells, SOCE was insensitive to BTP-2, 10 µM Gd3+ and Pyr6, while it was inhibited by 100 µM Gd3+, 2-APB, and carboxyamidotriazole (CAI. Neither Gd3+ nor 2-APB or CAI impaired mRCC cell proliferation. Consistently, no detectable Ca2+ signal was elicited by growth factor stimulation. Therefore, a functional SOCE is expressed but does not control proliferation of mRCC cells isolated from patients resistant to multikinase inhibitors.

  3. Pleomorphic adenoma of oral minor salivary glands: An investigation of its neoplastic potential based on apoptosis, mucosecretory activity and cellular proliferation.

    Science.gov (United States)

    Ferreira, Jean Carlos Barbosa; Morais, Marília Oliveira; Elias, Marcela Ramos Abrahão; Batista, Aline Carvalho; Leles, Claudio Rodriguês; Mendonça, Elismauro Francisco

    2014-06-01

    The aim of this study was to investigate the neoplastic potential of the PA of minor oral salivary glands measured by apoptosis (Bcl-2, Bax and p53), mucosecretory activity (MUC1), and cellular proliferation (Ki-67). Thirty-one cases of PA of the oral cavity and four controls (C) taken from normal oral minor salivary glands were analyzed using the immunohistochemistry technique. The proteins were detected utilizing a semi-quantitative method (scores) as follows: (-) negative ≤5%, (+) low 6-25%, (++) moderate 26-50% and (+++) high >50% of positive tumour cells. The apoptotic indices were evaluated by the ratio Bcl-2/Bax. Non-parametric comparison and correlation tests were used for analysis. The data showed high staining of anti-apoptotic protein Bcl-2 in both groups (PA=57.9%; C=67.7%) and a significantly lower expression of pro-apoptotic protein Bax (PA=22.7%; C=97.7%) and MUC1 (PA=14%; C=82.3%) in PA than in C (p0.05). The neoplastic potential of PA could be associated with an imbalance in apoptotic processes and a lower index of cellular proliferation. Mucosecretory activity does not play a significant role in primary PA. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Induction of cellular proliferation in a human astrocytoma cell line by a Trypanosoma cruzi-derived antigen: a mechanism of pathogenesis?

    Science.gov (United States)

    Duran-Rehbein, G A; Vargas-Zambrano, J C; Cuéllar, A; Puerta, C J; Gonzalez, J M

    2017-01-30

    Trypanosoma cruzi can compromise the human central nervous system (CNS) during acute infection or reactivation in immune-suppressed hosts. Astrocytes have been identified as targets of T. cruzi's CNS infection in humans. Despite a high degree of parasitism and cellular lysis by T. cruzi in vitro the number of astrocytoma cells did not change when compared to uninfected cultures. This work evaluated cellular proliferation, changes in Major Histocompatibility Complex (MHC) expression as a reflection of antigen processing, and cytokine (IL-6 & IL-8) secretion in a human astrocytoma cell line exposed to a trypomastigote-derived antigen. Light microscopy was used to evaluate the number of cells; MHC molecule expression, cell cycle and cytokine secretion were assessed by flow cytometry. The number of astrocytoma cells increased proportional to the amount of antigen used and the percentage of cells in G2/M phase was higher when compared to control cultures. Antigen exposure increased expression of MHC class II, but not MHC class I in comparison to cultures incubated without antigen. Astrocytoma cell secretion of IL-6 and IL-8 was unaffected by antigen exposure. These results suggest the participation of a trypomastigote-derived mediator that induces astrocytoma cell proliferation without an inflammatory response; which may contribute to the pathogenesis of neurologic Chagas disease.

  5. Classic Ras Proteins Promote Proliferation and Survival Via Distinct Phosphoproteome Alterations in Neurofibromin-Null Malignant Peripheral Nerve Sheath Tumor Cells

    Science.gov (United States)

    Brossier, Nicole M.; Prechtl, Amanda M.; Longo, Jody Fromm; Barnes, Stephen; Wilson, Landon S.; Byer, Stephanie J.; Brosius, Stephanie N.; Carroll, Steven L.

    2015-01-01

    Neurofibromin, the tumor suppressor encoded by the neurofibromatosis type 1 (NF1) gene, potentially suppresses the activation of H-Ras, N-Ras and K-Ras. However, it is not known whether these classic Ras proteins are hyperactivated in NF1-null nerve sheath tumors, how they contribute to tumorigenesis and what signaling pathways mediate their effects. Here we show that H-Ras, N-Ras and K-Ras are coexpressed with their activators, (guanine nucleotide exchange factors), in neurofibromin-null malignant peripheral nerve sheath tumor (MPNST) cells and that all 3 Ras proteins are activated. Dominant negative (DN) H-Ras, a pan-inhibitor of the classic Ras family, inhibited MPNST proliferation and survival, but not migration. However, NF1-null MPNST cells were variably dependent on individual Ras proteins. In some lines, ablation of H-Ras, N-Ras and/or K-Ras inhibited mitogenesis. In others, ablation of a single Ras protein had no effect on proliferation; in these lines, ablation of a single Ras protein resulted in compensatory increases in the activation and/or expression of other Ras proteins. Using mass spectrometry-based phosphoproteomics, we identified 7 signaling networks affecting morphology, proliferation and survival that are regulated by DN H-Ras. Thus, neurofibromin loss activates multiple classic Ras proteins that promote proliferation and survival by regulating several distinct signaling cascades. PMID:25946318

  6. Increased expression of fatty acid synthase provides a survival advantage to colorectal cancer cells via upregulation of cellular respiration.

    Science.gov (United States)

    Zaytseva, Yekaterina Y; Harris, Jennifer W; Mitov, Mihail I; Kim, Ji Tae; Butterfield, D Allan; Lee, Eun Y; Weiss, Heidi L; Gao, Tianyan; Evers, B Mark

    2015-08-07

    Fatty acid synthase (FASN), a lipogenic enzyme, is upregulated in colorectal cancer (CRC). Increased de novo lipid synthesis is thought to be a metabolic adaptation of cancer cells that promotes survival and metastasis; however, the mechanisms for this phenomenon are not fully understood. We show that FASN plays a role in regulation of energy homeostasis by enhancing cellular respiration in CRC. We demonstrate that endogenously synthesized lipids fuel fatty acid oxidation, particularly during metabolic stress, and maintain energy homeostasis. Increased FASN expression is associated with a decrease in activation of energy-sensing pathways and accumulation of lipid droplets in CRC cells and orthotopic CRCs. Immunohistochemical evaluation demonstrated increased expression of FASN and p62, a marker of autophagy inhibition, in primary CRCs and liver metastases compared to matched normal colonic mucosa. Our findings indicate that overexpression of FASN plays a crucial role in maintaining energy homeostasis in CRC via increased oxidation of endogenously synthesized lipids. Importantly, activation of fatty acid oxidation and consequent downregulation of stress-response signaling pathways may be key adaptation mechanisms that mediate the effects of FASN on cancer cell survival and metastasis, providing a strong rationale for targeting this pathway in advanced CRC.

  7. Epidermal growth factor receptor status in early stage breast cancer is associated with cellular proliferation but not cross-talk.

    Science.gov (United States)

    Stebbing, Justin; Thiyagarajan, Arun; Surendrakumar, Veena; Payne, Rachel; Krell, Jonathan; Szydlo, Richard; Peston, David; Lewis, Jacqueline S; Coombes, R Charles; Shousha, Sami

    2011-09-01

    The epidermal growth factor receptor (EGFR) is a therapeutic target in a number of settings in solid malignancies, but its role in breast cancer has remained unclear and controversial. In 810 primary breast cancers derived from patients suitable for cytotoxic chemotherapy, EGFR was prospectively measured and interactions with tumour and clinical correlates were tested to observe whether postulated cross-talk mechanisms are likely to modulate breast cancer metastasis and proliferation. A minority (79 tumours, 9.8%) were EGFR positive; in a multivariate analysis the likelihood of being EGFR positive was significantly increased for patients with grade 3 disease, compared with grade 1 (OR 15.6; 95% CI 2 to 122, p=0.0001), and for oestrogen receptor-negative status compared with positive (OR 24.1; 95% CI 12.7 to 46.00, p=0.0001). EGFR expression may play a role in breast cancer proliferation, but appears unlikely to modify tumour pathology via postulated mechanisms of oestrogen receptor/EGFR-mediated cross-talk.

  8. Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

    Science.gov (United States)

    Chorna, Nataliya E; Santos-Soto, Iván J; Carballeira, Nestor M; Morales, Joan L; de la Nuez, Janneliz; Cátala-Valentin, Alma; Chornyy, Anatoliy P; Vázquez-Montes, Adrinel; De Ortiz, Sandra Peña

    2013-01-01

    Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN), the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ) of the dentate gyrus (DG) and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v.) microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.

  9. Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

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    Nataliya E Chorna

    Full Text Available Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN, the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ of the dentate gyrus (DG and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v. microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.

  10. Effect of artemisia species on cellular proliferation and apoptosis in human breast cancer cells via estrogen receptor-related pathway.

    Science.gov (United States)

    Choi, Eunjeong; Kim, Gunhee

    2013-10-01

    To investigate the mechanism underlying the anticancer effect of Artemisia species through the inhibition of cell growth and induction of apoptosis in breast carcinoma cells. To evaluate the anticancer activity of methanol extracts of eight Artemisia species (Artemisia stolonifera, Artemisia selengensis, Artemisia japonica, Artemisia Montana, Artemisia capillaris, Artemisia sylvatica, Artemisia keiskeana, and Artemisia scoparia), we first investigated the proliferation of estrogen receptor (ER)-positive MCF-7 breast carcinoma cells exposed to 5 or 200 g/mL for 72 h. Apoptosis induction was assessed by an Annexin V binding assay in cells exposed to extracts at a high concentration (200 g/mL). To verify the mechanism of apoptosis, ER expression and its related signaling was investigated using an immunoblot assay under the same conditions. MCF-7 cells showed the strongest antiproliferative response to the tested extracts. However, a biphasic effect was observed: the extracts inhibited proliferation at high concentrations whereas they stimulated it at low ones. ER expression was similarly modulated by the extracts. However, all of the extracts induced apoptosis at a high concentration (200 g/mL). Compared to the control level, exposure to the extracts resulted in a remarkable increase in the shift of cell populations. The present study suggests that the tested Artemisia species exerted their anticancer effects through the induction of apoptosis via an ER-related pathway.

  11. Bromelain and N-acetylcysteine inhibit proliferation and survival of gastrointestinal cancer cells in vitro: significance of combination therapy.

    Science.gov (United States)

    Amini, Afshin; Masoumi-Moghaddam, Samar; Ehteda, Anahid; Morris, David Lawson

    2014-11-12

    Bromelain and N-acetylcysteine are two natural, sulfhydryl-containing compounds with good safety profiles which have been investigated for their benefits and application in health and disease for more than fifty years. As such, the potential values of these agents in cancer therapy have been variably reported in the literature. In the present study, the efficacy of bromelain and N-acetylcysteine in single agent and combination treatment of human gastrointestinal carcinoma cells was evaluated in vitro and the underlying mechanisms of effect were explored. The growth-inhibitory effects of bromelain and N-acetylcysteine, on their own and in combination, on a panel of human gastrointestinal carcinoma cell lines, including MKN45, KATO-III, HT29-5F12, HT29-5M21 and LS174T, were assessed by sulforhodamine B assay. Moreover, the influence of the treatment on the expression of a range of proteins involved in the regulation of cell cycle and survival was investigated by Western blot. The presence of apoptosis was also examined by TUNEL assay. Bromelain and N-acetylcysteine significantly inhibited cell proliferation, more potently in combination therapy. Drug-drug interaction in combination therapy was found to be predominantly synergistic or additive. Mechanistically, apoptotic bodies were detected in treated cells by TUNEL assay. Furthermore, Western blot analysis revealed diminution of cyclins A, B and D, the emergence of immunoreactive subunits of caspase-3, caspase-7, caspase-8 and cleaved PARP, withering or cleavage of procaspase-9, overexpression of cytochrome c, reduced expression of anti-apoptotic Bcl-2 and pro-survival phospho-Akt, the emergence of the autophagosomal marker LC3-II and deregulation of other autophagy-related proteins, including Atg3, Atg5, Atg7, Atg12 and Beclin 1. These results were more prominent in combination therapy. We report for the first time to our knowledge the growth-inhibitory and cytotoxic effects of bromelain and N-acetylcysteine, in

  12. Engagement of cellular prion protein with the co-chaperone Hsp70/90 organizing protein regulates the proliferation of glioblastoma stem-like cells.

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    Iglesia, Rebeca Piatniczka; Prado, Mariana Brandão; Cruz, Lilian; Martins, Vilma Regina; Santos, Tiago Góss; Lopes, Marilene Hohmuth

    2017-04-17

    Glioblastoma (GBM), a highly aggressive brain tumor, contains a subpopulation of glioblastoma stem-like cells (GSCs) that play roles in tumor maintenance, invasion, and therapeutic resistance. GSCs are therefore a promising target for GBM treatment. Our group identified the cellular prion protein (PrP C ) and its partner, the co-chaperone Hsp70/90 organizing protein (HOP), as potential target candidates due to their role in GBM tumorigenesis and in neural stem cell maintenance. GSCs expressing different levels of PrP C were cultured as neurospheres with growth factors, and characterized with stem cells markers and adhesion molecules markers through immunofluorescence and flow cytometry. We than evaluated GSC self-renewal and proliferation by clonal density assays and BrdU incorporation, respectively, in front of recombinant HOP treatment, combined or not with a HOP peptide which mimics the PrP C binding site. Stable silencing of HOP was also performed in parental and/or PrP C -depleted cell populations, and proliferation in vitro and tumor growth in vivo were evaluated. Migration assays were performed on laminin-1 pre-coated glass. We observed that, when GBM cells are cultured as neurospheres, they express specific stemness markers such as CD133, CD15, Oct4, and SOX2; PrP C is upregulated compared to monolayer culture and co-localizes with CD133. PrP C silencing downregulates the expression of molecules associated with cancer stem cells, upregulates markers of cell differentiation and affects GSC self-renewal, pointing to a pivotal role for PrP C in the maintenance of GSCs. Exogenous HOP treatment increases proliferation and self-renewal of GSCs in a PrP C -dependent manner while HOP knockdown disturbs the proliferation process. In vivo, PrP C and/or HOP knockdown potently inhibits the growth of subcutaneously implanted glioblastoma cells. In addition, disruption of the PrP C -HOP complex by a HOP peptide, which mimics the PrP C binding site, affects GSC self

  13. Grape seed and red wine polyphenol extracts inhibit cellular cholesterol uptake, cell proliferation, and 5-lipoxygenase activity.

    Science.gov (United States)

    Leifert, Wayne R; Abeywardena, Mahinda Y

    2008-12-01

    Accumulating evidence suggests that grape seed and wine polyphenol extracts possess a diverse array of actions and may be beneficial in the prevention of inflammatory-mediated disease such as cardiovascular disease and cancer. This study aimed to determine whether the reported pleiotropic effects of several polyphenolic extracts from grape seed products or red wine would also include inhibition of cholesterol uptake and cell proliferation, and inhibit a known specific target of the inflammatory process, that is, 5-lipoxygenase (5-LOX). Incubation of HT29, Caco2, HepG2, or HuTu80 cells in a medium containing [(3)H]cholesterol in the presence of a grape seed extract (GSE) or red wine polyphenolic compounds (RWPCs) inhibited [(3)H]cholesterol uptake by up to 66% (which appeared maximal). The estimated IC(50) values were 60 and 83 microg/mL for RWPC and GSE, respectively. Similar cholesterol uptake inhibitory effects were observed using the fluorescent cholesterol analogue NBD cholesterol. The inhibition of cholesterol uptake was independent of the sample's (GSE and RWPC) potent antioxidative capacity. Red wine polyphenolic compound and GSE dose dependently inhibited HT29 colon adenocarcinoma cell proliferation, which was accompanied by an increase in apoptosis. In addition, RWPC and GSE inhibited 5-LOX activity with the IC(50) values being 35 and 13 microg/mL, respectively. Two of 3 other GSEs tested also significantly inhibited 5-LOX activity. Inhibition of cholesterol uptake and proinflammatory 5-LOX activity may be beneficial in preventing the development of chronic degenerative diseases such as cardiovascular disease and cancer.

  14. Rapamycin attenuates BAFF-extended proliferation and survival via disruption of mTORC1/2 signaling in normal and neoplastic B-lymphoid cells.

    Science.gov (United States)

    Zeng, Qingyu; Qin, Shanshan; Zhang, Hai; Liu, Beibei; Qin, Jiamin; Wang, Xiaoxue; Zhang, Ruijie; Liu, Chunxiao; Dong, Xiaoqing; Zhang, Shuangquan; Huang, Shile; Chen, Long

    2018-01-01

    B cell activating factor from the TNF family (BAFF) stimulates B-cell proliferation and survival, but excessive BAFF promotes the development of aggressive B cells leading to malignant and autoimmune diseases. Recently, we have reported that rapamycin, a macrocyclic lactone, attenuates human soluble BAFF (hsBAFF)-stimulated B-cell proliferation/survival by suppressing mTOR-mediated PP2A-Erk1/2 signaling pathway. Here, we show that the inhibitory effect of rapamycin on hsBAFF-promoted B cell proliferation/survival is also related to blocking hsBAFF-stimulated phosphorylation of Akt, S6K1, and 4E-BP1, as well as expression of survivin in normal and B-lymphoid (Raji and Daudi) cells. It appeared that both mTORC1 and mTORC2 were involved in the inhibitory activity of rapamycin, as silencing raptor or rictor enhanced rapamycin's suppression of hsBAFF-induced survivin expression and proliferation/viability in B cells. Also, PP242, an mTORC1/2 kinase inhibitor, repressed survivin expression, and cell proliferation/viability more potently than rapamycin (mTORC1 inhibitor) in B cells in response to hsBAFF. Of interest, ectopic expression of constitutively active Akt (myr-Akt) or constitutively active S6K1 (S6K1-ca), or downregulation of 4E-BP1 conferred resistance to rapamycin's attenuation of hsBAFF-induced survivin expression and B-cell proliferation/viability, whereas overexpression of dominant negative Akt (dn-Akt) or constitutively hypophosphorylated 4E-BP1 (4EBP1-5A), or downregulation of S6K1, or co-treatment with Akt inhibitor potentiated the inhibitory effects of rapamycin. The findings indicate that rapamycin attenuates excessive hsBAFF-induced cell proliferation/survival via blocking mTORC1/2 signaling in normal and neoplastic B-lymphoid cells. Our data underscore that rapamycin may be a potential agent for preventing excessive BAFF-evoked aggressive B-cell malignancies and autoimmune diseases. © 2017 Wiley Periodicals, Inc.

  15. Tolerance to Gamma Radiation in the Tardigrade Hypsibius dujardini from Embryo to Adult Correlate Inversely with Cellular Proliferation.

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    Eliana Beltrán-Pardo

    Full Text Available Tardigrades are highly tolerant to desiccation and ionizing radiation but the mechanisms of this tolerance are not well understood. In this paper, we report studies on dose responses of adults and eggs of the tardigrade Hypsibius dujardini exposed to gamma radiation. In adults the LD50/48h for survival was estimated at ~ 4200 Gy, and doses higher than 100 Gy reduced both fertility and hatchability of laid eggs drastically. We also evaluated the effect of radiation (doses 50 Gy, 200 Gy, 500 Gy on eggs in the early and late embryonic stage of development, and observed a reduced hatchability in the early stage, while no effect was found in the late stage of development. Survival of juveniles from irradiated eggs was highly affected by a 500 Gy dose, both in the early and the late stage. Juveniles hatched from eggs irradiated at 50 Gy and 200 Gy developed into adults and produced offspring, but their fertility was reduced compared to the controls. Finally we measured the effect of low temperature during irradiation at 4000 Gy and 4500 Gy on survival in adult tardigrades, and observed a slight delay in the expressed mortality when tardigrades were irradiated on ice. Since H. dujardini is a freshwater tardigrade with lower tolerance to desiccation compared to limno-terrestrial tardigrades, the high radiation tolerance in adults, similar to limno-terrestrial tardigrades, is unexpected and seems to challenge the idea that desiccation and radiation tolerance rely on the same molecular mechanisms. We suggest that the higher radiation tolerance in adults and late stage embryos of H. dujardini (and in other studied tardigrades compared to early stage embryos may partly be due to limited mitotic activity, since tardigrades have a low degree of somatic cell division (eutely, and dividing cells are known to be more sensitive to radiation.

  16. Role of the amygdala in antidepressant effects on hippocampal cell proliferation and survival and on depression-like behavior in the rat.

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    Jorge E Castro

    Full Text Available The stimulation of adult hippocampal neurogenesis by antidepressants has been associated with multiple molecular pathways, but the potential influence exerted by other brain areas has received much less attention. The basolateral complex of the amygdala (BLA, a region involved in anxiety and a site of action of antidepressants, has been implicated in both basal and stress-induced changes in neural plasticity in the dentate gyrus. We investigated here whether the BLA modulates the effects of the SSRI antidepressant fluoxetine on hippocampal cell proliferation and survival in relation to a behavioral index of depression-like behavior (forced swim test. We used a lesion approach targeting the BLA along with a chronic treatment with fluoxetine, and monitored basal anxiety levels given the important role of this behavioral trait in the progress of depression. Chronic fluoxetine treatment had a positive effect on hippocampal cell survival only when the BLA was lesioned. Anxiety was related to hippocampal cell survival in opposite ways in sham- and BLA-lesioned animals (i.e., negatively in sham- and positively in BLA-lesioned animals. Both BLA lesions and low anxiety were critical factors to enable a negative relationship between cell proliferation and depression-like behavior. Therefore, our study highlights a role for the amygdala on fluoxetine-stimulated cell survival and on the establishment of a link between cell proliferation and depression-like behavior. It also reveals an important modulatory role for anxiety on cell proliferation involving both BLA-dependent and -independent mechanisms. Our findings underscore the amygdala as a potential target to modulate antidepressants' action in hippocampal neurogenesis and in their link to depression-like behaviors.

  17. Expression of R132H mutational IDH1 in human U87 glioblastoma cells affects the SREBP1a pathway and induces cellular proliferation.

    Science.gov (United States)

    Zhu, Jian; Cui, Gang; Chen, Ming; Xu, Qinian; Wang, Xiuyun; Zhou, Dai; Lv, Shengxiang; Fu, Linshan; Wang, Zhong; Zuo, Jianling

    2013-05-01

    Sterol regulatory element-binding protein-1a (SREBP1a) is a member of the SREBP family of transcription factors, which mainly controls homeostasis of lipids. SREBP1a can also activate the transcription of isocitrate dehydrogenase 1 (IDH1) by binding to its promoter region. IDH1 mutations, especially R132H mutation of IDH1, are a common feature of a major subset of human gliomas. There are few data available on the relationship between mutational IDH1 expression and SREBP1a pathway. In this study, we investigated cellular effects and SREBP1a pathway alterations caused by R132H mutational IDH1 expression in U87 cells. Two glioma cell lines, stably expressing mutational (U87/R132H) or wild type (U87/wt) IDH1, were established. A cell line, stably transfected with pcDNA3.1(+) (U87/vector), was generated as a control. Click-iT EdU assay, sulforhodamine B assay, and wound healing assay respectively showed that the expression of R132H induced cellular proliferation, cell growth, and cell migration. Western blot revealed that SREBP1 was increased in U87/R132H compared with that in U87/wt. Elevated SREBP1a and several its target genes, but not SREBP1c, were detected by real-time polymerase chain reaction in U87/R132H. All these findings indicated that R132H mutational IDH1 is involved in the regulation of proliferation, growth, and migration of glioma cells. These effects may partially be mediated by SREBP1a pathway.

  18. The cellular prion protein PrP(c is involved in the proliferation of epithelial cells and in the distribution of junction-associated proteins.

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    Etienne Morel

    Full Text Available BACKGROUND: The physiological function of the ubiquitous cellular prion protein, PrP(c, is still under debate. It was essentially studied in nervous system, but poorly investigated in epithelial cells. We previously reported that PrP(c is targeted to cell-cell junctions of polarized epithelial cells, where it interacts with c-Src. METHODOLOGY/FINDINGS: We show here that, in cultured human enterocytes and in intestine in vivo, the mature PrP(c is differentially targeted either to the nucleus in dividing cells or to cell-cell contacts in polarized/differentiated cells. By proteomic analysis, we demonstrate that the junctional PrP(c interacts with cytoskeleton-associated proteins, such as gamma- and beta-actin, alpha-spectrin, annexin A2, and with the desmosome-associated proteins desmoglein, plakoglobin and desmoplakin. In addition, co-immunoprecipitation experiments revealed complexes associating PrP(c, desmoglein and c-Src in raft domains. Through siRNA strategy, we show that PrP(c is necessary to complete the process of epithelial cell proliferation and for the sub-cellular distribution of proteins involved in cell architecture and junctions. Moreover, analysis of the architecture of the intestinal epithelium of PrP(c knock-out mice revealed a net decrease in the size of desmosomal junctions and, without change in the amount of BrdU incorporation, a shortening of the length of intestinal villi. CONCLUSIONS/SIGNIFICANCE: From these results, PrP(c could be considered as a new partner involved in the balance between proliferation and polarization/differentiation in epithelial cells.

  19. Metabolic and cellular plasticity in white adipose tissue II: role of peroxisome proliferator-activated receptor-alpha.

    Science.gov (United States)

    Li, Pipeng; Zhu, Zhengxian; Lu, Yuyan; Granneman, James G

    2005-10-01

    Chronic activation of adipocyte beta-adrenergic receptors induces remodeling of white adipose tissue (WAT) that includes a transient inflammatory response followed by mitochondrial biogenesis, induction of fatty acid oxidation genes, and elevation of tissue oxidative metabolism. Gene profiling experiments of WAT during remodeling induced by the beta(3)-adrenergic receptor agonist CL-316,243 (CL) suggested that peroxisome proliferator-activated receptor-alpha (Ppara), which is upregulated by CL, might be an important transcriptional regulator of that process. Histological, physiological, and molecular analysis of CL-induced remodeling in wild-type mice and mice lacking Ppara demonstrated that Ppara was important for inducing adipocyte mitochondrial biogenesis and upregulating genes involved in fatty acid oxidation. Furthermore, Ppara-deficient mice exhibited sustained WAT inflammation during CL treatment, indicating that upregulation of Ppara limits proinflammatory signaling during chronic lipolytic activation. Together, these data support the hypothesis that WAT remodeling is an adaptive response to excessive fatty acid mobilization whereby Ppara and its downstream targets elevate fatty acid catabolism and suppress proinflammatory signaling.

  20. Heterogeneous Nuclear Ribonucleoprotein K Supports Vesicular Stomatitis Virus Replication by Regulating Cell Survival and Cellular Gene Expression

    Science.gov (United States)

    Dinh, Phat X.; Das, Anshuman; Franco, Rodrigo

    2013-01-01

    The heterogeneous nuclear ribonucleoprotein K (hnRNP K) is a member of the family of hnRNPs and was recently shown in a genome-wide small interfering RNA (siRNA) screen to support vesicular stomatitis virus (VSV) growth. To decipher the role of hnRNP K in VSV infection, we conducted studies which suggest that the protein is required for VSV spreading. Virus binding to cells, entry, and nucleocapsid uncoating steps were not adversely affected in the absence of hnRNP K, whereas viral genome transcription and replication were reduced slightly. These results indicate that hnRNP K is likely involved in virus assembly and/or release from infected cells. Further studies showed that hnRNP K suppresses apoptosis of virus-infected cells, resulting in increased cell survival during VSV infection. The increased survival of the infected cells was found to be due to the suppression of proapoptotic proteins such as Bcl-XS and Bik in a cell-type-dependent manner. Additionally, depletion of hnRNP K resulted in not only significantly increased levels of T-cell-restricted intracellular antigen 1 (TIA1) but also switching of the expression of the two isoforms of the protein (TIA1a and TIA1b), both of which inhibited VSV replication. hnRNP K was also found to support expression of several cellular proteins known to be required for VSV infection. Overall, our studies demonstrate hnRNP K to be a multifunctional protein that supports VSV infection via its role(s) in suppressing apoptosis of infected cells, inhibiting the expression of antiviral proteins, and maintaining the expression of proteins required for the virus. PMID:23843646

  1. Gene Expression of Glucose Transporter 1 (GLUT1, Hexokinase 1 and Hexokinase 2 in Gastroenteropancreatic Neuroendocrine Tumors: Correlation with F-18-fluorodeoxyglucose Positron Emission Tomography and Cellular Proliferation

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    Andreas Kjaer

    2013-10-01

    Full Text Available Neoplastic tissue exhibits high glucose utilization and over-expression of glucose transporters (GLUTs and hexokinases (HKs, which can be imaged by 18F-Fluorodeoxyglucose-positron emission tomography (FDG-PET. The aim of the present study was to investigate the expression of glycolysis-associated genes and to compare this with FDG-PET imaging as well as with the cellular proliferation index in two cancer entities with different malignant potential. Using real-time PCR, gene expression of GLUT1, HK1 and HK2 were studied in 34 neuroendocrine tumors (NETs in comparison with 14 colorectal adenocarcinomas (CRAs. The Ki67 proliferation index and, when available, FDG-PET imaging was compared with gene expression. Overexpression of GLUT1 gene expression was less frequent in NETs (38% compared to CRAs (86%, P = 0.004. HK1 was overexpressed in 41% and 71% of NETs and CRAs, respectively (P = 0.111 and HK2 was overexpressed in 50% and 64% of NETs and CRAs, respectively (P = 0.53. There was a significant correlation between the Ki67 proliferation index and GLUT1 gene expression for the NETs (R = 0.34, P = 0.047, but no correlation with the hexokinases. FDG-PET identified foci in significantly fewer NETs (36% than CRAs (86%, (P = 0.04. The gene expression results, with less frequent GLUT1 and HK1 upregulation in NETs, confirmed the lower metabolic activity of NETs compared to the more aggressive CRAs. In accordance with this, fewer NETs were FDG-PET positive compared to CRA tumors and FDG uptake correlated with GLUT1 gene expression.

  2. TRANSGENIC GDNF POSITIVELY INFLUENCES PROLIFERATION, DIFFERENTIATION, MATURATION AND SURVIVAL OF MOTOR NEURONS PRODUCED FROM MOUSE EMBRYONIC STEM CELLS.

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    Daniel Édgar Cortés

    2016-09-01

    Full Text Available Embryonic stem cells (ESC are pluripotent and thus can differentiate into every cell type present in the body. Directed differentiation into motor neurons has been described for pluripotent cells. Although neurotrophic factors promote neuronal survival, their role in neuronal commitment is elusive. Here, we developed double-transgenic lines of mouse ESC that constitutively produce Glial cell-derived neurotrophic factor (GDNF and also contain a GFP reporter, driven by HB9, which is expressed only by postmitotic motor neurons. After lentiviral transduction, ESC lines integrated and expressed the human GDNF gene without altering pluripotency markers before differentiation. Further, GDNF-ESC showed significantly higher spontaneous release of this neurotrophin to the medium, when compared to controls. To study motor neuron induction, control and GDNF cell lines were grown as embryoid bodies and stimulated with retinoic acid and Sonic Hedgehog. In GDNF-overexpressing cells, a significant increase of proliferative Olig2+ precursors, which are specified as spinal motor neurons, was found. Accordingly, GDNF increases the yield of cells with the pan motor neuronal markers HB9, monitored by GFP expression, and Isl1. At terminal differentiation, almost all differentiated neurons express phenotypic markers of motor neurons in GDNF cultures, with lower proportions in control cells. To test if the effects of GDNF were present at early differentiation stages, exogenous recombinant human GDNF was added to control ESC, also resulting in enhanced motor neuron differentiation. This effect was abolished by the co-addition of neutralizing anti-GDNF antibodies, strongly suggesting that differentiating ESC are responsive to GDNF. Using the HB9::GFP reporter, motor neurons were selected for electrophysiological recordings. Motor neurons differentiated from GDNF-ESC, compared to control motor neurons, showed greater electrophysiological maturation, characterized by

  3. Strong anti-Epstein Barr virus (EBV or cytomegalovirus (CMV cellular immune responses predict survival and a favourable response to anti-tuberculosis therapy

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    Tumaini Nagu

    2017-03-01

    Conclusions: Increased cellular immune responses to CMV and EBV antigens at the time of diagnosis of pulmonary tuberculosis are associated with increased survival after a standard six months anti-TB therapy. CVM and EBV antigens may represent “intrinsic markers for immune fitness” and guide improved TB therapies including host-directed therapies.

  4. Long non-coding RNA lnc-MX1-1 is associated with poor clinical features and promotes cellular proliferation and invasiveness in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Chen-Yi; Gao, Yuan; Wang, Xing-Jie [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Ruan, Yuan [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Department of Urology, Shanghai General Hospital Affiliated to Nanjing Medical University, Shanghai 200080 (China); Bei, Xiao-Yu; Wang, Xiao-Hai; Jing, Yi-Feng; Zhao, Wei; Jiang, Qi [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Li, Jia; Han, Bang-Min [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Institute of Urology, Shanghai Jiao Tong University, Shanghai 200080 (China); Xia, Shu-Jie [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Department of Urology, Shanghai General Hospital Affiliated to Nanjing Medical University, Shanghai 200080 (China); Institute of Urology, Shanghai Jiao Tong University, Shanghai 200080 (China); Zhao, Fu-Jun, E-mail: drzhaofujun@yahoo.com [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Institute of Urology, Shanghai Jiao Tong University, Shanghai 200080 (China)

    2016-02-12

    Long non-coding RNAs (lncRNAs) are emerging as key molecules in human cancer genesis and progression, including prostate cancer. Large amount of lncRNAs have been found that differentially expressed between prostate cancer tissues and normal prostate tissues. Whether these lncRNAs could serve as a novel biomarker for prostate cancer diagnosis or prognosis, and their biological functions in prostate cancer need further investigation. In the present study, we identified that lncRNA lnc-MX1-1 is over-expressed in prostate cancer tissues compared with their adjacent normal prostate tissues by gene expression array profiling. The expression of lnc-MX1-1 in 60 prostate cancer cases was determined by real-time quantitative PCR and the correlations between lnc-MX1-1 expression and patients' clinical features were further analyzed. Next, we impaired lnc-MX1-1 expression using RNAi in LNCaP and 22Rv1 prostate cancer cells to explore the effects of lnc-MX1-1 on proliferation and invasiveness of the cells. Our results showed that there was a significant association between over-expression of lnc-MX1-1 and patients' clinical features such as PSA, Gleason score, metastasis, and recurrence free survival. Moreover, knockdown of lnc-MX1-1 reduced both proliferation and invasiveness of LNCaP and 22Rv1 cells. In conclusion, the results suggest that lnc-MX1-1 may serve as a potential biomarker and therapeutic target for prostate cancer. - Highlights: • LncRNA lnc-MX1-1 is up-regulated in prostate cancer. • Overexpression of lnc-MX1-1 is correlated with poor prostate cancer clinical features. • Knockdown of lnc-MX1-1 reduces proliferation and invasiveness of prostate cancer cells.

  5. Expression of GLUT-1 in epithelial ovarian carcinoma: correlation with tumor cell proliferation, angiogenesis, survival and ability to predict optimal cytoreduction.

    Science.gov (United States)

    Semaan, Assaad; Munkarah, Adnan R; Arabi, Haitham; Bandyopadhyay, Sudeshna; Seward, Shelly; Kumar, Sanjeev; Qazi, Aamer; Hussein, Yasser; Morris, Robert T; Ali-Fehmi, Rouba

    2011-04-01

    GLUT-1 is involved at various steps in the processes of tumor progression. The objective of this study was to examine the relationship between GLUT-1 expression and tumor proliferation and angiogenesis in epithelial ovarian carcinoma. Specimens from 213 patients with epithelial ovarian carcinoma were evaluated by immunohistochemistry for GLUT-1, Ki-67, and vascular endothelial growth factor. Tumor microvessel density was assessed with CD34 immunostaining. We investigated the relationships between GLUT-1 expression and clinicopathologic characteristics, tumor angiogenesis (tumor MVD and vascular endothelial growth factor expression), and tumor proliferation (Ki-67). The effect of GLUT-1 expression on patient survival and on the volume of residual disease after cytoreduction was determined. There was a significant positive correlation between expression of GLUT-1, Ki-67, and microvessel density. In univariate survival analysis, high GLUT-1 expression, high Ki-67 expression and high tumor microvessel density showed a significant impact on patient survival (p=0.0001). In multivariate analysis including patients with all tumor stages, after controlling for age, race, stage, grade, MVD, and the 3 markers (GLUT-1, Ki-67 and VEGF), only age (HR 1.5; 95% CI 1-2.3), stage (HR 3.6; 95% CI 1.8-7.5) and grade (HR 2.3; 95% CI 1.2-4.5) retained their significance as independent poor prognostic factors. Tumors simultaneously overexpressing GLUT-1 and Ki-67 were less likely to be optimally cytoreduced as compared to tumors overexpressing only one or neither of those two markers (OR: 3.8, p=0.01). Expression of GLUT-1 correlates with tumor proliferation and microvessel density in epithelial ovarian carcinoma. In addition, patients with rapidly proliferating advanced stage tumors overexpressing GLUT-1 have a lesser chance for optimal cytoreduction. Copyright © 2010 Elsevier Inc. All rights reserved.

  6. Survival

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide information on the survival of California red-legged frogs in a unique ecosystem to better conserve this threatened species while restoring...

  7. Abrogation of E-cadherin-mediated cellular aggregation allows proliferation of pluripotent mouse embryonic stem cells in shake flask bioreactors.

    Directory of Open Access Journals (Sweden)

    Lisa Mohamet

    2010-09-01

    Full Text Available A fundamental requirement for the exploitation of embryonic stem (ES cells in regenerative medicine is the ability to reproducibly derive sufficient numbers of cells of a consistent quality in a cost-effective manner. However, undifferentiated ES cells are not ideally suited to suspension culture due to the formation of cellular aggregates, ultimately limiting scalability. Significant advances have been made in recent years in the culture of ES cells, including automated adherent culture and suspension microcarrier or embryoid body bioreactor culture. However, each of these methods exhibits specific disadvantages, such as high cost, additional downstream processes or reduced cell doubling times.Here we show that abrogation of the cell surface protein E-cadherin, using either gene knockout (Ecad-/- or the neutralising antibody DECMA-1 (EcadAb, allows culture of mouse ES cells as a near-single cell suspension in scalable shake flask culture over prolonged periods without additional media supplements. Both Ecad-/- and EcadAb ES cells exhibited adaptation phases in suspension culture, with optimal doubling times of 7.3 h±0.9 and 15.6 h±4.7 respectively and mean-fold increase in viable cell number of 95.1±2.0 and 16±0.9-fold over 48 h. EcadAb ES cells propagated as a dispersed cell suspension for 15 d maintained expression of pluripotent markers, exhibited a normal karyotype and high viability. Subsequent differentiation of EcadAb ES cells resulted in expression of transcripts and proteins associated with the three primary germ layers.This is the first demonstration of the culture of pluripotent ES cells as a near-single cell suspension in a manual fed-batch shake flask bioreactor and represents a significant improvement on current ES cell culture techniques. Whilst this proof-of-principle method would be useful for the culture of human ES and iPS cells, further steps are necessary to increase cell viability of hES cells in suspension.

  8. The MRC-5 human embryonal lung fibroblast two-dimensional gel cellular protein database: quantitative identification of polypeptides whose relative abundance differs between quiescent, proliferating and SV40 transformed cells

    DEFF Research Database (Denmark)

    Celis, J E; Dejgaard, K; Madsen, Peder

    1990-01-01

    (1323 with isoelectric focusing and 572 with nonequilibrium pH gradient electrophoresis) are recorded in this database, containing quantitative and qualitative data on the relative abundance of cellular proteins synthesized by quiescent, proliferating and SV40 transformed MRC-5 fibroblasts. Of the 592......A new version of the MRC-5 two-dimensional gel cellular protein database (Celis et al., Electrophoresis 1989, 10, 76-115) is presented. Gels were scanned with a Molecular Dynamics laser scanner and processed by the PDQUEST II software. A total of 1895 [35S]methionine-labeled cellular polypeptides...

  9. Specific blockade by CD54 and MHC II of CD40-mediated signaling for B cell proliferation and survival

    DEFF Research Database (Denmark)

    Doyle, I S; Hollmann, C A; Crispe, I N

    2001-01-01

    Regulation of B lymphocyte proliferation is critical to maintenance of self-tolerance, and intercellular interactions are likely to signal such regulation. Here, we show that coligation of either the adhesion molecule ICAM-1/CD54 or MHC II with CD40 inhibited cell cycle progression and promoted a...

  10. RNAi targeting Nogo Receptor enhanced survival and proliferation of murine retinal ganglion cells during N-methyl-D-aspartate-induced optic nerve crush.

    Science.gov (United States)

    Zeng, Kun; Zhong, Bo; Shen, Xiao-Li; Fang, Min; Lin, Bao-Tao; Ma, Da-Hui

    2017-09-12

    We investigated the effects of lentivirus-mediated RNAi targeting of Nogo Receptor ( NgR ) on the proliferation and survival of murine retinal ganglion cells (mRGCs) in vitro and in vivo . Cultured mRGCs and C57BL/6 male mice were divided into 4 experimental groups: blank, model [100 μM N-methyl-D-aspartate (NMDA)], nscRNA (100 μM NMDA+ nscRNA vectors) and siNgR (100 μM NMDA+ siNgR vectors). CCK-8 and flow cytometry analyses revealed that silencing NgR enhanced proliferation, cell cycling and survival of NMDA-treated mRGCs. H&E staining showed that NgR silencing enhanced mRGC cell density and reduced angiogenesis in NMDA-treated retinal tissues. TUNEL assays showed that mRGC apoptosis was significantly diminished by NgR silencing in NMDA-treated retinal tissues. Western blotting and qRT-PCR analysis in NMDA-treated mRGCs and murine retinal tissues revealed that NgR silencing resulted in downregulation of RhoA signaling (RhoA and ROCK2). Western blotting showed that levels of activated Bax and cleaved caspase 3 were decreased, while Bcl-2 and pro-caspase 3 were increased in NMDA-treated mRGCs and murine retinal tissues, which corroborated the decreased apoptosis. These findings indicate that NgR gene silencing increases proliferation and survival of mRGCs in NMDA-treated murine retinas, which suggests a potential for therapeutic application to preventing optic nerve damage.

  11. Cellular growth and survival are mediated by beta 1 integrins in normal human breast epithelium but not in breast carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Howlett, Anthony R; Bailey, Nina; Damsky, Caroline; Petersen, Ole W; Bissell, Mina J

    1994-11-28

    We previously established a rapid three-dimensional assay for discrimination of normal and malignant human breast epithelial cells using a laminin-rich reconstituted basement membrane. In this assay, normal epithelial cells differentiate into well-organized acinar structures whereas tumor cells fail to recapitulate this process and produce large, disordered colonies. The data suggest that breast acinar morphogenesis and differentiation is regulated by cell-extracellular matrix (ECM) interactions and that these interactions are altered in malignancy. Here, we investigated the role of ECM receptors (integrins) in these processes and report on the expression and function of potential laminin receptors in normal and tumorigenic breast epithelial cells. Immmunocytochemical analysis showed that normal and carcinoma cells in a three-dimensional substratum express profiles of integrins similar to normal and malignant breast tissues in situ. Normal cells express {alpha}1, {alpha}2, {alpha}3, {alpha}6, {beta}1 and {beta}4 integrin subunits, whereas breast carcinoma cells show variable losses, disordered expression, or down regulation of these subunits. Function-blocking experiments using inhibitory antiintegrin subunit antibodies showed a >5-fold inhibition of the formation of acinar structures by normal cells in the presence of either anti-{beta}1 or anti-{alpha}3 antibodies, whereas anti-{alpha}2 or -{alpha}6 had little or no effect. In experiments where collagen type I gels were used instead of basement membrane, acinar morphogenesis was blocked by anti-{beta}1 and -{alpha}2 antibodies but not by anti-{alpha}3. These data suggest a specificity of integrin utilization dependent on the ECM ligands encountered by the cell. The interruption of normal acinar morphogenesis by anti-integrin antibodies was associated with an inhibition of cell growth and induction of apoptosis. Function-blocking antibodies had no inhibitory effect on the rate of tumor cell growth, survival or

  12. Blockage of Wnt/β-Catenin Signaling by Nanoparticles Reduces Survival and Proliferation of CLL Cells In Vitro-Preliminary Study.

    Science.gov (United States)

    Franiak-Pietryga, Ida; Maciejewski, Henryk; Ziemba, Barbara; Appelhans, Dietmar; Voit, Brigitte; Robak, Tadeusz; Jander, Magdalena; Treliński, Jacek; Bryszewska, Maria; Borowiec, Maciej

    2017-11-01

    The Wnt/β-catenin signaling pathway is shown to play a significant role in the control of the survival, proliferation, and differentiation of hematopoietic cells. Studies have confirmed that aberrant activation of canonical Wnt signaling occurs in various forms of leukemia, and is crucial for chronic lymphocytic leukemia (CLL) pathogenesis. The aim of the study is to evaluate the influence of maltotriose (M3) modified fourth generation poly(propylene imine) dendrimers (PPI-G4) on Wnt/β-catenin pathway gene expression in CLL (MEC-1) cells and to compare these findings with those obtained with fludarabine (FA). Microarray data analysis reveals seven of 19 Wnt/β-catenin pathway genes whose expression changes significantly during dendrimer and FA treatment: WNT10A, WNT6, and CDH1 among others. PPI-G4-M3 is already known to influence MEC-1 cell apoptosis and proliferation. The obtained results suggest that the reduction in cell survival under the influence of glycodendrimers and FA may be due to loss of Wnt signaling. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. In situ normoxia enhances survival and proliferation rate of human adipose tissue-derived stromal cells without increasing the risk of tumourigenesis.

    Directory of Open Access Journals (Sweden)

    Jane Ru Choi

    Full Text Available Adipose tissue-derived stromal cells (ASCs natively reside in a relatively low-oxygen tension (i.e., hypoxic microenvironment in human body. Low oxygen tension (i.e., in situ normoxia, has been known to enhance the growth and survival rate of ASCs, which, however, may lead to the risk of tumourigenesis. Here, we investigated the tumourigenic potential of ASCs under their physiological condition to ensure their safe use in regenerative therapy. Human ASCs isolated from subcutaneous fat were cultured in atmospheric O2 concentration (21% O2 or in situ normoxia (2% O2. We found that ASCs retained their surface markers, tri-lineage differentiation potential, and self-renewal properties under in situ normoxia without altering their morphology. In situ normoxia displayed a higher proliferation and viability of ASCs with less DNA damage as compared to atmospheric O2 concentration. Moreover, low oxygen tension significantly up-regulated VEGF and bFGF mRNA expression and protein secretion while reducing the expression level of tumour suppressor genes p16, p21, p53, and pRb. However, there were no significant differences in ASCs telomere length and their relative telomerase activity when cultured at different oxygen concentrations. Collectively, even with high proliferation and survival rate, ASCs have a low tendency of developing tumour under in situ normoxia. These results suggest 2% O2 as an ideal culture condition for expanding ASCs efficiently while maintaining their characteristics.

  14. SLC25A22 Promotes Proliferation and Survival of Colorectal Cancer Cells With KRAS Mutations and Xenograft Tumor Progression in Mice via Intracellular Synthesis of Aspartate.

    Science.gov (United States)

    Wong, Chi Chun; Qian, Yun; Li, Xiaona; Xu, Jiaying; Kang, Wei; Tong, Joanna H; To, Ka-Fai; Jin, Ye; Li, Weilin; Chen, Huarong; Go, Minnie Y Y; Wu, Jian-Lin; Cheng, Ka Wing; Ng, Simon S M; Sung, Joseph J Y; Cai, Zongwei; Yu, Jun

    2016-11-01

    Many colorectal cancer (CRC) cells contain mutations in KRAS. Analyses of CRC cells with mutations in APC or CTNNB1 and KRAS identified SLC25A22, which encodes mitochondrial glutamate transporter, as a synthetic lethal gene. We investigated the functions of SLC25A22 in CRC cells with mutations in KRAS. We measured levels of SLC25A22 messenger RNA and protein in paired tumor and nontumor colon tissues collected from 130 patients in Hong Kong and 17 patients in China and compared protein levels with patient survival times. Expression of SLC25A22 was knocked down in KRAS mutant CRC cell lines (DLD1, HCT116, LOVO, SW480, SW620, and SW1116) and CRC cell lines without mutations in KRAS (CACO-2, COLO205, HT29, and SW48); cells were analyzed for colony formation, proliferation, glutaminolysis and aspartate synthesis, and apoptosis in Matrigel and polymerase chain reaction array analyses. DLD1 and HCT116 cells with SLC25A22 knockdown were grown as xenograft tumors in nude mice; tumor growth and metastasis were measured. SLC25A22 was expressed ectopically in HCT116 cells, which were analyzed in vitro and grown as xenograft tumors in nude mice. Levels of SLC25A22 messenger RNA and protein were increased in colorectal tumor tissues compared with matched nontumor colon tissues; increased protein levels were associated with shorter survival times of patients (P = .01). Knockdown of SLC25A22 in KRAS mutant CRC cells reduced their proliferation, migration, and invasion in vitro, and tumor formation and metastasis in mice, compared with cells without SLC25A22 knockdown. Knockdown of SLC25A22 reduced aspartate biosynthesis, leading to apoptosis, decreased cell proliferation in KRAS mutant CRC cells. Incubation of KRAS mutant CRC cells with knockdown of SLC25A22 with aspartate increased proliferation and reduced apoptosis, which required GOT1, indicating that oxaloacetate is required for cell survival. Decreased levels of oxaloacetate in cells with knockdown of SLC25A22 reduced

  15. Association of Sphingosine-1-phosphate (S1P)/S1P Receptor-1 Pathway with Cell Proliferation and Survival in Canine Hemangiosarcoma.

    Science.gov (United States)

    Rodriguez, A M; Graef, A J; LeVine, D N; Cohen, I R; Modiano, J F; Kim, J-H

    2015-01-01

    Sphingosine-1-phosphate (S1P) is a key biolipid signaling molecule that regulates cell growth and survival, but it has not been studied in tumors from dogs. S1P/S1P1 signaling will contribute to the progression of hemangiosarcoma (HSA). Thirteen spontaneous HSA tissues, 9 HSA cell lines, 8 nonmalignant tissues, including 6 splenic hematomas and 2 livers with vacuolar degeneration, and 1 endothelial cell line derived from a dog with splenic hematoma were used. This was a retrospective case series and in vitro study. Samples were obtained as part of medically necessary diagnostic procedures. Microarray, qRT-PCR, immunohistochemistry, and immunoblotting were performed to examine S1P1 expression. S1P concentrations were measured by high-performance liquid chromatography/mass spectrometry. S1P signaling was evaluated by intracellular Ca(2+) mobilization; proliferation and survival were evaluated using the MTS assay and Annexin V staining. Canine HSA cells expressed higher levels of S1P1 mRNA than nonmalignant endothelial cells. S1P1 protein was present in HSA tissues and cell lines. HSA cells appeared to produce low levels of S1P, but they selectively consumed S1P from the culture media. Exogenous S1P induced an increase in intracellular calcium as well as increased proliferation and viability of HSA cells. Prolonged treatment with FTY720, an inhibitor of S1P1 , decreased S1P1 protein expression and induced apoptosis of HSA cells. S1P/S1P1 signaling pathway functions to maintain HSA cell viability and proliferation. The data suggest that S1P1 or the S1P pathway in general could be targets for therapeutic intervention for dogs with HSA. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  16. Species-specific control of cellular proliferation and the impact of large animal models for the use of olfactory ensheathing cells and Schwann cells in spinal cord repair.

    Science.gov (United States)

    Wewetzer, Konstantin; Radtke, Christine; Kocsis, Jeffery; Baumgärtner, Wolfgang

    2011-05-01

    Autologous transplantation of olfactory ensheathing cells (OECs) and Schwann cells (SCs) is considered a promising option to promote axonal regrowth and remyelination after spinal cord injury in humans. However, if the experimental data from the rodent model can be directly extrapolated to humans, as widely believed, remains to be established. While limitations of the rodent system have recently been discussed with regard to the distinct organization of the motor systems, the question whether OECs and SCs may display species-specific properties has not been fully addressed. Prompted by recent studies on canine and porcine glia, we performed a detailed analysis of the in vitro and in vivo properties of OECs and SCs and show that rodent but not human, monkey, porcine, and canine glia require mitogens for in vitro expansion, display a complex response to elevated intracellular cAMP, and undergo spontaneous immortalization upon prolonged mitogen stimulation. These data indicate fundamental inter-species differences of the control of cellular proliferation. Whether OECs and SCs from large animals and humans share growth-promoting in vivo properties with their rodent counterpart is not yet clear. Autologous implantation studies in humans did not reveal adverse effects of cell transplantation so far. However, in vivo studies of large animal or human glia and rodent recipients mainly focused on the remyelinating potential of the transplanted cells. Thus, further experimental in vivo studies in large animals are essential to fully define the axonal growth-promoting potential of OECs and SCs. Based on the homology of the in vitro growth control between porcine, canine and human glia, it is concluded that these species may serve as valuable translational models for scaling up human procedures. This article is part of a Special Issue entitled: Understanding olfactory ensheathing glia and their prospect for nervous system repair. Copyright © 2010 Elsevier Inc. All rights

  17. Cellular stress-induced up-regulation of FMRP promotes cell survival by modulating PI3K-Akt phosphorylation cascades

    Directory of Open Access Journals (Sweden)

    Wells David

    2011-02-01

    Full Text Available Abstract Background Fragile X syndrome (FXS, the most commonly inherited mental retardation and single gene cause of autistic spectrum disorder, occurs when the Fmr1 gene is mutated. The product of Fmr1, fragile X linked mental retardation protein (FMRP is widely expressed in HeLa cells, however the roles of FMRP within HeLa cells were not elucidated, yet. Interacting with a diverse range of mRNAs related to cellular survival regulatory signals, understanding the functions of FMRP in cellular context would provide better insights into the role of this interesting protein in FXS. Using HeLa cells treated with etoposide as a model, we tried to determine whether FMRP could play a role in cell survival. Methods Apoptotic cell death was induced by etoposide treatment on Hela cells. After we transiently modulated FMRP expression (silencing or enhancing by using molecular biotechnological methods such as small hairpin RNA virus-induced knock down and overexpression using transfection with FMRP expression vectors, cellular viability was measured using propidium iodide staining, TUNEL staining, and FACS analysis along with the level of activation of PI3K-Akt pathway by Western blot. Expression level of FMRP and apoptotic regulator BcL-xL was analyzed by Western blot, RT-PCR and immunocytochemistry. Results An increased FMRP expression was measured in etoposide-treated HeLa cells, which was induced by PI3K-Akt activation. Without FMRP expression, cellular defence mechanism via PI3K-Akt-Bcl-xL was weakened and resulted in an augmented cell death by etoposide. In addition, FMRP over-expression lead to the activation of PI3K-Akt signalling pathway as well as increased FMRP and BcL-xL expression, which culminates with the increased cell survival in etoposide-treated HeLa cells. Conclusions Taken together, these results suggest that FMRP expression is an essential part of cellular survival mechanisms through the modulation of PI3K, Akt, and Bcl-xL signal

  18. miRNA array analysis determines miR-205 is overexpressed in head and neck squamous cell carcinoma and enhances cellular proliferation

    Directory of Open Access Journals (Sweden)

    Howard JD

    2013-08-01

    Full Text Available MicroRNAs (miRNAs play a critical role in cell cycle and pro-survival signal regulation. Consequently, their deregulation can enhance tumorigenesis and cancer progression. In the current investigation, we determined whether cancer- or human papillomavirus (HPV-specific miRNA deregulation could further elucidate signal transduction events unique to head and neck squamous cell carcinoma (HNSCC. Twenty-nine newly diagnosed HNSCC tumors (HPV-positive: 14, HPV-negative: 15 and four normal mucosa samples were analyzed for global miRNA expression. Differential miRNA expression analysis concluded HNSCC is characterized by a general upregulation of miRNAs compared to normal mucosa. Additionally, miR-449a and miR-129-3p were statistically significant miRNAs differentially expressed between HPV-positive and HPV-negative HNSCC. The upregulation of miR-449a was also validated within an independent dataset obtained from TCGA containing 279 HNSCCs and 39 normal adjacent mucosa samples. To gain a better understanding of miRNA-mediated cell cycle deregulation in HNSCC, we functionally evaluated miR-205, a transcript upregulated in our cancer-specific analysis and a putative regulator of E2F1. Modulation of miR-205 with a miRNA mimic and inhibitor revealed miR-205 is capable of regulating E2F1 expression in HNSCC and overexpression of this transcript enhances proliferation. This study demonstrates miRNA expression is highly deregulated in HNSCC and functional evaluations of these miRNAs may reveal novel HPV context dependent mechanisms in this disease.

  19. Over-expression of 60s ribosomal L23a is associated with cellular proliferation in SAG resistant clinical isolates of Leishmania donovani.

    Directory of Open Access Journals (Sweden)

    Sanchita Das

    Full Text Available Sodium antimony gluconate (SAG unresponsiveness of Leishmania donovani (Ld had effectively compromised the chemotherapeutic potential of SAG. 60s ribosomal L23a (60sRL23a, identified as one of the over-expressed protein in different resistant strains of L.donovani as observed with differential proteomics studies indicates towards its possible involvement in SAG resistance in L.donovani. In the present study 60sRL23a has been characterized for its probable association with SAG resistance mechanism.The expression profile of 60s ribosomal L23a (60sRL23a was checked in different SAG resistant as well as sensitive strains of L.donovani clinical isolates by real-time PCR and western blotting and was found to be up-regulated in resistant strains. Ld60sRL23a was cloned, expressed in E.coli system and purified for raising antibody in swiss mice and was observed to have cytosolic localization in L.donovani. 60sRL23a was further over-expressed in sensitive strain of L.donovani to check its sensitivity profile against SAG (Sb V and III and was found to be altered towards the resistant mode.This study reports for the first time that the over expression of 60sRL23a in SAG sensitive parasite decreases the sensitivity of the parasite towards SAG, miltefosine and paramomycin. Growth curve of the tranfectants further indicated the proliferative potential of 60sRL23a assisting the parasite survival and reaffirming the extra ribosomal role of 60sRL23a. The study thus indicates towards the role of the protein in lowering and redistributing the drug pressure by increased proliferation of parasites and warrants further longitudinal study to understand the underlying mechanism.

  20. MYC through miR-17-92 Suppresses Specific Target Genes to Maintain Survival, Autonomous Proliferation, and a Neoplastic State

    KAUST Repository

    Li, Yulin

    2014-08-01

    The MYC oncogene regulates gene expression through multiple mechanisms, and its overexpression culminates in tumorigenesis. MYC inactivation reverses turmorigenesis through the loss of distinguishing features of cancer, including autonomous proliferation and survival. Here we report that MYC via miR-17-92 maintains a neoplastic state through the suppression of chromatin regulatory genes Sin3b, Hbp1, Suv420h1, and Btg1, as well as the apoptosis regulator Bim. The enforced expression of miR-17-92 prevents MYC suppression from inducing proliferative arrest, senescence, and apoptosis and abrogates sustained tumor regression. Knockdown of the five miR-17-92 target genes blocks senescence and apoptosis while it modestly delays proliferative arrest, thus partially recapitulating miR-17-92 function. We conclude that MYC, via miR-17-92, maintains a neoplastic state by suppressing specific target genes.

  1. Effects of cIAP-1, cIAP-2 and XIAP triple knockdown on prostate cancer cell susceptibility to apoptosis, cell survival and proliferation.

    LENUS (Irish Health Repository)

    Gill, Catherine

    2009-01-01

    BACKGROUND: Manipulating apoptotic resistance represents an important strategy for the treatment of hormone refractory prostate cancer. We hypothesised that the Inhibitor of Apoptosis (IAP) Proteins may be mediating this resistance and knockdown of cIAP-1, cIAP-2 and XIAP would increase sensitivity to apoptosis. METHODS: cIAP-1, cIAP-2 and XIAP where knocked down either individually or in combination using siRNA in androgen independent prostate cancer PC-3 cells as confirmed by real-time PCR and western blotting. Cells were then treated with TRAIL, Etoposide, or Tunicamycin, and apoptosis assessed by PI DNA staining. Apoptosis was confirmed with Annexin V labelling and measurement of PARP cleavage, and was inhibited using the pan-caspase inhibitor, zVAD.fmk. Clonogenic assays and assessment of ID-1 expression by western blotting were used to measure recovery and proliferation. RESULTS: PC-3 are resistant to TRAIL induced apoptosis and have elevated expression of cIAP-1, cIAP-2 and XIAP. Combined knockdown sensitised PC-3 to TRAIL induced apoptosis, but not to Etoposide or Tunicmycin, with corresponding increases in caspase activity and PARP cleavage which was inhibited by ZVAD.fmk. Triple knock down decreased proliferation which was confirmed by decreased ID-1 expression. CONCLUSION: Simultaneous knock down of the IAPs not only sensitised the PC-3 to TRAIL but also inhibited their proliferation rates and clonogenic survival. The inability to alter sensitivity to other triggers of apoptosis suggests that this effect is specific for death receptor pathways and knock down might facilitate immune-surveillance mechanisms to counter cancer progression and, in combination with therapeutic approaches using TRAIL, could represent an important treatment strategy.

  2. Effects of cIAP-1, cIAP-2 and XIAP triple knockdown on prostate cancer cell susceptibility to apoptosis, cell survival and proliferation

    Directory of Open Access Journals (Sweden)

    Dowling Catherine

    2009-06-01

    Full Text Available Abstract Background Manipulating apoptotic resistance represents an important strategy for the treatment of hormone refractory prostate cancer. We hypothesised that the Inhibitor of Apoptosis (IAP Proteins may be mediating this resistance and knockdown of cIAP-1, cIAP-2 and XIAP would increase sensitivity to apoptosis. Methods cIAP-1, cIAP-2 and XIAP where knocked down either individually or in combination using siRNA in androgen independent prostate cancer PC-3 cells as confirmed by real-time PCR and western blotting. Cells were then treated with TRAIL, Etoposide, or Tunicamycin, and apoptosis assessed by PI DNA staining. Apoptosis was confirmed with Annexin V labelling and measurement of PARP cleavage, and was inhibited using the pan-caspase inhibitor, zVAD.fmk. Clonogenic assays and assessment of ID-1 expression by western blotting were used to measure recovery and proliferation. Results PC-3 are resistant to TRAIL induced apoptosis and have elevated expression of cIAP-1, cIAP-2 and XIAP. Combined knockdown sensitised PC-3 to TRAIL induced apoptosis, but not to Etoposide or Tunicmycin, with corresponding increases in caspase activity and PARP cleavage which was inhibited by ZVAD.fmk. Triple knock down decreased proliferation which was confirmed by decreased ID-1 expression. Conclusion Simultaneous knock down of the IAPs not only sensitised the PC-3 to TRAIL but also inhibited their proliferation rates and clonogenic survival. The inability to alter sensitivity to other triggers of apoptosis suggests that this effect is specific for death receptor pathways and knock down might facilitate immune-surveillance mechanisms to counter cancer progression and, in combination with therapeutic approaches using TRAIL, could represent an important treatment strategy.

  3. Association of high HLA-E expression during acute cellular rejection and numbers of HLA class I leader peptide mismatches with reduced renal allograft survival.

    Science.gov (United States)

    Guberina, Hana; Rebmann, Vera; Wagner, Bettina; da Silva Nardi, Fabiola; Dziallas, Phillip; Dolff, Sebastian; Bienholz, Anja; Wohlschlaeger, Jeremias; Bankfalvi, Agnes; Heinemann, Falko M; Witzke, Oliver; Zoet, Yvonne M; Claas, Frans H J; Horn, Peter A; Kribben, Andreas; Doxiadis, Ilias I N

    2017-03-01

    Non-classical Human Leukocyte Antigen (HLA)-E preferentially presents leader peptides derived from classical HLA-class I molecules. HLA-E can trigger opposed immune responses by interacting with inhibitory NKG2A or by activating NKG2C receptors on NK and T-cells. We studied the impact of HLA-E on renal allograft survival during acute cellular rejection. HLA-E expression was up-regulated in acute cellular rejection (ACR) biopsies (n=12) compared to biopsies from 13 renal allografts with no rejection-signs. HLA-E up-regulation was correlated with numbers of HLA-class I leader peptide mismatches (p=0.04). CD8+ and CD56+ infiltrating cells correlated with HLA-E expression (pleader peptides might represent additional targets for immune-activating responses. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. Survival, proliferation and differentiation enhancement of neural stem cells cultured in three-dimensional polyethylene glycol-RGD hydrogel with tenascin.

    Science.gov (United States)

    Naghdi, Pejman; Tiraihi, Taki; Ganji, Fariba; Darabi, Shehram; Taheri, Taher; Kazemi, Hadi

    2016-03-01

    Polyethylene glycol hydrogel (PEG) conjugated with arginyl glycyl aspartic acid (RGD) (PEG-RGD) has been considered to be a scaffold in three-dimensional (3D) culture that improves neurite outgrowth; on the other hand, tenascin C controls neural growth and differentiation. In this study, the effect of a combined RGD and tenascin C mixture in 3D culture (3D-PEG-RGD-TnC) on the survival, growth and differentiation of neural stem cells. The viability of the culture has been evaluated by live/dead assay and the results show that the viability of NSCs in 3D-PEG-RGD-TnC is significantly higher than its value in 3D-PEG-RGD. The proliferation was evaluated by MTS test and was found to be slightly improved but statistically not significant. Accordingly, the differentiation was evaluated by immunoreactivity to nestin, neurofilament 68, neurofilament 160, neurofilament 200 and GFAP; and the expression of nestin, neuro D, musashi1, β-tubulin III, GFAP, MBP and Oct4 was studied using RT-PCR. The results showed enhancement of the differentiation of NSCs into the neuronal phenotype in 3D-PEG-RGD-TnC. The morphology of NSCs cultured in 3D-PEG-RGD-TnC showed neurite outgrowths and increase in the contact between the differentiated cells' extensions. The conclusion of this study was that NSC survival, proliferation and differentiation are enhanced when the cells are cultured in 3D-PEG-RGD-TnC. Copyright © 2014 John Wiley & Sons, Ltd.

  5. Behavioural Effects of Adult Vitamin D Deficiency in BALB/c Mice Are not Associated with Proliferation or Survival of Neurons in the Adult Hippocampus.

    Directory of Open Access Journals (Sweden)

    Natalie J Groves

    Full Text Available Epidemiological studies have shown that up to one third of adults have insufficient levels of vitamin D and there is an association between low vitamin D concentrations and adverse brain outcomes, such as depression. Vitamin D has been shown to be involved in processes associated with neurogenesis during development. Therefore, the aim of this study was to test the hypothesis that adult vitamin D (AVD deficiency in BALB/c mice was associated with (a adult hippocampal neurogenesis at baseline, b following 6 weeks of voluntary wheel running and (c a depressive-like phenotype on the forced swim test (FST, which may be linked to alterations in hippocampal neurogenesis. We assessed proliferation and survival of adult born hippocampal neurons by counting the number of cells positive for Ki67 and doublecortin (DCX, and incorporation of 5-Bromo-2'-Deoxyuridine (BrdU within newly born mature neurons using immunohistochemistry. There were no significant effects of diet on number of Ki67+, DCX+ or BrdU+ cells in the dentate gyrus. All mice showed significantly increased number of Ki67+ cells and BrdU incorporation, and decreased immobility time in the FST, after voluntary wheel running. A significant correlation was found in control mice between immobility time in the FST and level of hippocampal neurogenesis, however, no such correlation was found for AVD-deficient mice. We conclude that AVD deficiency was not associated with impaired proliferation or survival of adult born neurons in BALB/c mice and that the impact on rodent behaviour may not be due to altered neurogenesis per se, but to altered function of new hippocampal neurons or processes independent of adult neurogenesis.

  6. Proteomic characterisation reveals active Wnt-signalling by human multipotent stromal cells as a key regulator of beta cell survival and proliferation.

    Science.gov (United States)

    Kuljanin, Miljan; Bell, Gillian I; Sherman, Stephen E; Lajoie, Gilles A; Hess, David A

    2017-10-01

    Novel strategies to stimulate the expansion of beta cell mass in situ are warranted for diabetes therapy. The aim of this study was to elucidate the secretome of human bone marrow (BM)-derived multipotent stromal cells (MSCs) with documented islet regenerative paracrine function. We hypothesised that regenerative MSCs will secrete a unique combination of protein factors that augment islet regeneration. Human BM-derived MSCs were examined for glucose-lowering capacity after transplantation into streptozotocin-treated NOD/severe combined immunodeficiency (SCID) mice and segregated into samples with regenerative (MSC(R)) vs nonregenerative (MSC(NR)) capacity. Secreted proteins associated with islet regenerative function were identified using stable isotope labelling with amino acids in cell culture (SILAC)-based quantitative proteomics. To functionally validate the importance of active Wnt signalling, we stimulated the Wnt-signalling pathway in MSC(NR) samples during ex vivo expansion using glycogen synthase kinase 3 (GSK3) inhibition (CHIR99201), and the conditioned culture media (CM) generated was tested for the capacity to support cultured human islet cell survival and proliferation in vitro. MSC(R) showed increased secretion of proteins associated with cell growth, matrix remodelling, immunosuppressive and proangiogenic properties. In contrast, MSC(NR) uniquely secreted proteins known to promote inflammation and negatively regulate angiogenesis. Most notably, MSC(R) maintained Wnt signalling via Wnt5A/B (~2.5-fold increase) autocrine activity during ex vivo culture, while MSC(NR) repressed Wnt signalling via Dickkopf-related protein (DKK)1 (~2.5-fold increase) and DKK3 secretion. Inhibition of GSK3 activity in MSC(NR) samples increased the accumulation of nuclear β-catenin and generated CM that augmented beta cell survival (13% increases) and proliferation when exposed to cultured human islets. Maintenance of active Wnt signalling within human MSCs promotes the

  7. TGF-β1 activates the canonical NF-κB signaling to promote cell survival and proliferation in dystrophic muscle fibroblasts in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhen-Yu [Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou 510080, Guangdong Province (China); Department of Neurology, The Second Affiliated Hospital, Guangzhou Medical University, No.250 Changgang East Road, Guangzhou 510260, Guangdong Province (China); Zhong, Zhi-Gang; Qiu, Meng-Yao; Zhong, Yu-Hua [Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou 510080, Guangdong Province (China); Zhang, Wei-Xi, E-mail: weixizhang@qq.com [Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou 510080, Guangdong Province (China)

    2016-03-18

    Activated fibroblasts continue to proliferate at injury sites, leading to progressive muscular fibrosis in Duchenne muscular dystrophy (DMD). TGF-β1 is a dominant profibrotic mediator thought to play a critical role in muscle fibrosis; however, the implicated mechanisms are not fully understood. Here we showed that TGF-β1 increased the resistance to apoptosis and stimulated cell cycle progression in dystrophic muscle fibroblasts under serum deprivation conditions in vitro. TGF-β1 treatment activated the canonical NF-κB pathway; and we found that pharmacological inhibition of IKKβ with IMD-0354 and RelA gene knockdown with siRNA attenuated these effects of TGF-β1 on dystrophic muscle fibroblasts. Collectively, our data suggest that TGF-β1 prevents apoptosis and cell cycle arrest in dystrophic muscle fibroblasts through the canonical NF-κB signaling pathway. - Highlights: • TGF-β1 promotes survival and proliferation in dystrophic muscle fibroblasts. • TGF-β1 activated the canonical NF-κB pathway in dystrophic muscle fibroblasts. • Canonical NF-κB pathway mediates these effects of TGF-β1.

  8. Modulation of the uptake of critical nutrients by breast cancer cells by lactate: Impact on cell survival, proliferation and migration.

    Science.gov (United States)

    Guedes, Marta; Araújo, João R; Correia-Branco, Ana; Gregório, Inês; Martel, Fátima; Keating, Elisa

    2016-02-15

    This work aimed to characterize the uptake of folate and glucose by breast cancer cells and to study the effect of lactate upon the transport of these nutrients and upon cell viability, proliferation and migration capacity. Data obtained showed that: a) MCF7 cells uptake (3)H-folic acid ((3)H-FA) at physiological but not at acidic pH; b) T47D cells accumulate (3)H-FA and (14)C-5-methyltetrahydrofolate ((14)C-5-MTHF) more efficiently at acidic than at physiological pH; c) (3)H-deoxyglucose ((3)H-DG) uptake by T47D cells is sodium-independent, inhibited by cytochalasin B (CYT B) and stimulated by insulin. Regarding the effect of lactate, in T47D cells, acute (26 min) and chronic (24 h) exposure to lactic acid (LA) stimulated (3)H-FA uptake. Acute exposure to LA also stimulated (3)H-DG uptake and chronic exposure to LA significantly stimulated T47D cell migratory capacity. In conclusion, the transport of folates is strikingly different in two phenotypically similar breast cancer cell lines: MCF7 and T47D cells. Additionally, lactate seems to act as a signaling molecule which increases the uptake of nutrients and promotes the migration capacity of T47D cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. RB1CC1 activates RB1 pathway and inhibits proliferation and cologenic survival in human cancer.

    Directory of Open Access Journals (Sweden)

    Tokuhiro Chano

    2010-06-01

    Full Text Available RB1-inducible coiled-coil 1 (RB1CC1, also known as FIP200 plays a role in the enhancement of the RB1 pathway through the direct binding to a GC-rich region 201bp upstream (from the initiation ATG of the RB1 promoter. Here, we identified hSNF5 and p53 as the binding partners of RB1CC1 by immunoprecipitation and immunofluorescence assays. Interaction between these molecules and the RB1 pathway was analyzed by the assays of chromatin immunoprecipitation, luciferase-reporter, reverse transcription-polymerase chain reaction and immunoblot. The tumor growth suppression by RB1CC1 was evaluated by flow cytometry or by a cell growth assay. The nuclear RB1CC1 complex involving hSNF5 and/or p53 activated transcription of RB1, p16 and p21, and suppressed tumor cell growth. Furthermore, nuclear RB1CC1 expression significantly correlated with those of RB1 and p16 in breast cancer tissue in vivo, and the Ki-67 proliferation index was dependent on p53 as well as RB1CC1. The present study indicates that RB1CC1 together with hSNF5 and/or p53 enhances the RB1 pathway through transcriptional activation of RB1, p16 and p21. Evaluation of RB1CC1 expression combined with RB1 and p53 status is expected to provide useful information in clinical practice and future therapeutic strategies in breast cancer.

  10. Sublethal pesticide doses negatively affect survival and the cellular responses in American foulbrood-infected honeybee larvae

    Science.gov (United States)

    López, Javier Hernández; Krainer, Sophie; Engert, Antonia; Schuehly, Wolfgang; Riessberger-Gallé, Ulrike; Crailsheim, Karl

    2017-02-01

    Disclosing interactions between pesticides and bee infections is of most interest to understand challenges that pollinators are facing and to which extent bee health is compromised. Here, we address the individual and combined effect that three different pesticides (dimethoate, clothianidin and fluvalinate) and an American foulbrood (AFB) infection have on mortality and the cellular immune response of honeybee larvae. We demonstrate for the first time a synergistic interaction when larvae are exposed to sublethal doses of dimethoate or clothianidin in combination with Paenibacillus larvae, the causative agent of AFB. A significantly higher mortality than the expected sum of the effects of each individual stressor was observed in co-exposed larvae, which was in parallel with a drastic reduction of the total and differential hemocyte counts. Our results underline that characterizing the cellular response of larvae to individual and combined stressors allows unmasking previously undetected sublethal effects of pesticides in colony health.

  11. ANCA-stimulated neutrophils release BLyS and promote B cell survival: a clinically relevant cellular process.

    Science.gov (United States)

    Holden, N J; Williams, J M; Morgan, M D; Challa, A; Gordon, J; Pepper, R J; Salama, A D; Harper, L; Savage, C O S

    2011-12-01

    To determine a role for antineutrophil cytoplasmic antibody (ANCA)-activated neutrophils in promoting B cell survival through the release of B lymphocyte stimulator (BLyS). Neutrophil BLyS expression was measured by flow cytometry. Concentrations of BLyS in cell supernatants and donor serum samples were measured by ELISA. Cell survival assays were carried out using an L3055 cell line and viability measured by flow cytometry. Tumour necrosis factor α and formyl-Met-Leu-Phe (fMLP) treatment of non-primed neutrophils and treatment of primed neutrophils with anti-PR3 ANCA IgG resulted in a significant increase in surface expression of BLyS within 30 min which returned to basal levels by 2 h. Supernatants from ANCA-stimulated neutrophils were shown to contain increased levels of BLyS and to promote the survival of the centroblast cell line L3055. Serum BLyS concentrations are increased in patients with active ANCA-associated systemic vasculitis and these levels are increased further following 1-3 months of treatment with rituximab. ANCA specifically causes the release of BLyS from activated neutrophils which can support B cell survival in vitro. The presence of serum BLyS in active disease and its increase following B cell depletion suggest it is an important factor in disease pathogenesis and may facilitate disease relapse.

  12. Nuclear Localization of DNAJB6 Is Associated With Survival of Patients With Esophageal Cancer and Reduces AKT Signaling and Proliferation of Cancer Cells.

    Science.gov (United States)

    Yu, Valen Zhuoyou; Wong, Victor Chun-Lam; Dai, Wei; Ko, Josephine Mun-Yee; Lam, Alfred King-Yin; Chan, Kwok Wah; Samant, Rajeev S; Lung, Hong Lok; Shuen, Wai Ho; Law, Simon; Chan, Yuen Piu; Lee, Nikki Pui-Yue; Tong, Daniel King Hung; Law, Tsz Ting; Lee, Victor Ho-Fun; Lung, Maria Li

    2015-12-01

    The DnaJ (Hsp40) homolog, subfamily B, member 6 (DNAJB6) is part of a family of proteins that regulates chaperone activities. One of its isoforms, DNAJB6a, contains a nuclear localization signal and regulates β-catenin signaling during breast cancer development. We investigated the role of DNAJB6 in the pathogenesis of esophageal squamous cell carcinoma (ESCC). We performed immunohistochemical analyses of primary ESCC samples and lymph node metastases from a cohort of 160 patients who underwent esophagectomy with no preoperative chemoradiotherapy at Hong Kong Queen Mary Hospital. Data were collected on patient outcomes over a median time of 12.1 ± 2.9 months. Retrospective survival association analyses were performed. Wild-type and mutant forms of DNAJB6a were overexpressed in cancer cell lines (KYSE510, KYSE 30TSI, KYSE140, and KYSE70TS), which were analyzed in proliferation and immunoblot assays, or injected subcutaneously into nude mice. Levels of DNAJB6 were knocked down in ESCC cell lines (KYSE450 and T.Tn), immortalized normal esophageal epithelial cell lines (NE3 and NE083), and other cells with short hairpin RNAs, or by genome engineering. Bimolecular fluorescence complementation was used to study interactions between proteins in living cells. In primary ESCC samples, patients whose tumors had high nuclear levels of DNAJB6 had longer overall survival times (19.2 ± 1.8 months; 95% confidence interval [CI], 15.6-22.8 mo) than patients whose tumors had low nuclear levels of DNAJB6 (12.6 ± 1.4 mo; 95% CI, 9.8-15.4 mo; P = .004, log-rank test). Based on Cox regression analysis, patients whose tumors had high nuclear levels of DNAJB6 had a lower risk of death than patients with low levels (hazard ratio, 0.562; 95% CI, 0.379-0.834; P = .004). Based on log-rank analysis and Cox regression analysis, the combination of the nuclear level of DNAJB6 and the presence of lymph node metastases at diagnosis could be used to stratify patients into groups with good or

  13. Mad2 overexpression is associated with high cell proliferation and reduced disease-free survival in primary gastrointestinal diffuse large B-cell lymphoma.

    Science.gov (United States)

    Chen, Fei; Liu, Shangqin; Zhou, Yi; Shen, Hui; Zuo, Xuelan

    2016-08-01

    Primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL) is a rare hematological malignancy with limited results on carcinogenesis and clinical characteristics. The aims of the current study were to examine mitotic arrest deficiency protein 2 (Mad2) expressions in PGI-DLBCL, and assess its association with Ki-67 expression, Helicobacter pylori (H. pylori) infection, BCL-6 gene rearrangement, and clinicopathological variables. Cancer tissues from 38 PGI-DLBCL patients were examined for Mad2, Ki-67, and H. pylori expression by immunohistochemistry, using normal gastrointestinal tissues and nodal DLBCL as controls. BCL-6 gene translocation was analyzed by fluorescence in situ hybridization (FISH), and Mad2 expression status was evaluated along with clinicopathological characteristics. Mad2 expression was increased in PGI-DLBCL patients when compared with controls. The expression of Mad2 was 51.55 ± 22.88% in PGI-DLBCL, which was higher than reactive lymph node (28.77 ± 10.89%) and lymphoid nodule in normal gastrointestinal tissue (26.41 ± 11.30%) (P = 0.002), while it was comparable to nodal DLBCL (57.23 ± 20.79%) (P = 0.358). Mad2 overexpression had a positive correlation with Ki-67 proliferation index (r = 0.55, P = 0.01) in PGI-DLBCL, and patients with BCL-6 gene rearrangement had lower Mad2 expression (P = 0.032) than patients with intact BCL-6, while no relation was found between Mad2 expression and H. pylori infection. PGI-DLBCL patients with higher Mad2 expression had lower estimated disease-free survival (DFS) (17.10% vs. 53.00%) (P = 0.049). However, no correlation was found between Mad2 expression levels and overall survival (OS) (P = 0.443). Aberrant Mad2 expression was associated with cell proliferation and genetic instability, which may contribute to the carcinogenesis of PGI-DLBCL. Mad2 overexpression indicated a poor DFS and may be a potential biomarker for estimating prognosis for PGI

  14. Microarray analysis reveals that leptin induces autocrine/paracrine cascades to promote survival and proliferation of colon epithelial cells in an Apc genotype-dependent fashion.

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    Fenton, Jenifer I; Lavigne, Jackie A; Perkins, Susan N; Liu, Huaitian; Chandramouli, Gadisetti V R; Shih, Joanna H; Hord, Norman G; Hursting, Stephen D

    2008-01-01

    The imbalance in systemic mediators of inflammation, such as leptin, is thought to be involved in obesity-associated cancers. In addition, systemic endocrine signals can influence the local autocrine/paracrine factors produced within this microenvironment to influence epithelial cell fate. We previously demonstrated that leptin preferentially promotes the survival and proliferation of colon epithelial cells possessing an Apc mutation (IMCE) but not model normal cells (YAMC). Therefore, the purpose of this study was to identify leptin-induced functional gene family changes which characterize the response of colon epithelial cells possessing an Apc mutation but not normal cells. Consistent with our knowledge of colon carcinogenesis, genes regulating the Wnt/beta-catenin-mediated pathway including Mdm2, Pik3r1, and Rb1 were upregulated by leptin. Importantly, leptin induced IGF-mediated pathway gene expression changes and their protein products in IMCE cells. In the IMCE cells IGFBP-6, IGF-1, and Crim1 expression was upregulated, while IGFBP-2, IGFBP-3, IGFBP-4, IGFBP-5, and Nov expression was downregulated by leptin treatment. These data establish a biologically plausible mechanistic link between the elevated levels of growth factors and the increased risk of colon cancer associated with obesity. (c) 2007 Wiley-Liss, Inc.

  15. Paraffin embedding allows effective analysis of proliferation, survival, and immunophenotyping of cells cultured on poly(l-lactic acid) electrospun nanofiber scaffolds.

    Science.gov (United States)

    Foroni, Laura; Dirani, Giorgio; Gualandi, Chiara; Focarete, Maria Letizia; Pasquinelli, Gianandrea

    2010-08-01

    Morphological and immunophenotypic characterization of cells grown on poly(l-lactic acid) (PLLA) electrospun scaffolds is usually performed using immunofluorescence and cryosections. However, these methods present practical limits; histological processing, on the other hand, is believed to lead to artifactual changes in the scaffold structure. Here the formalin-fixed paraffin-embedding (FFPE) procedure was tailored to process PLLA electrospun scaffolds grown with human umbilical vein endothelial cells. After 1 to 7 days of culture, the scaffolds were processed with the FFPE procedure. Using this protocol, not only cross sections but also "en face" sections were obtained. This made possible to perform the effective light microscopy analysis of cell morphology and to assess cell adhesion and penetration without considerable scaffold damage. The method was also suitable for immunohistochemical assays, such as proliferation (Ki67), extracellular matrix production (type IV collagen), survival (cleaved caspase-3), and immunophenotyping (KDR, CD44, vimentin, CD45); results were compared with those obtained using complementary techniques (scanning electron microscopy, Alamar Blue assay, and cryosections). The FFPE protocol can be safely applied to PLLA scaffolds and provides information that are essential to study the mechanisms of interaction between cells and PLLA fibers before their potential implantation in vivo.

  16. Effects of four Fusarium toxins (fumonisin B(1), alpha-zearalenol, nivalenol and deoxynivalenol) on porcine whole-blood cellular proliferation.

    Science.gov (United States)

    Luongo, D; De Luna, R; Russo, R; Severino, L

    2008-07-01

    The in vitro effects of four Fusarium toxins, fumonisin B(1) (FB(1)), alpha-zearalenol (alpha-ZEA), nivalenol (NIV) and deoxynivalenol (DON), on mitogen-induced cell proliferation were determined in swine whole-blood cultures. Considering the lack of sufficient toxicological data both on single and in combination effects, in vitro studies may contribute to risk assessment of these toxins. Incubation with increasing concentrations of FB(1) did not produce any consequence on proliferation; in contrast alpha-ZEA, NIV and DON showed an inhibitory effect. Dose-response curves for each mycotoxin were generated. NIV was found to be the most potent toxin followed by DON and alpha-ZEA. The effects of both FB(1)+alpha-ZEA and NIV+DON mixtures were also analysed to investigate possible interactions. The results indicated that combination of FB(1)+alpha-ZEA produces a synergistic inhibition of porcine cell proliferation; whereas there is no interaction between DON and NIV on porcine whole-blood proliferation, at tested concentrations.

  17. Dynamic cellular finite-element method for modelling large-scale cell migration and proliferation under the control of mechanical and biochemical cues: a study of re-epithelialization.

    Science.gov (United States)

    Zhao, Jieling; Cao, Youfang; DiPietro, Luisa A; Liang, Jie

    2017-04-01

    Computational modelling of cells can reveal insight into the mechanisms of the important processes of tissue development. However, current cell models have limitations and are challenged to model detailed changes in cellular shapes and physical mechanics when thousands of migrating and interacting cells need to be modelled. Here we describe a novel dynamic cellular finite-element model (DyCelFEM), which accounts for changes in cellular shapes and mechanics. It also models the full range of cell motion, from movements of individual cells to collective cell migrations. The transmission of mechanical forces regulated by intercellular adhesions and their ruptures are also accounted for. Intra-cellular protein signalling networks controlling cell behaviours are embedded in individual cells. We employ DyCelFEM to examine specific effects of biochemical and mechanical cues in regulating cell migration and proliferation, and in controlling tissue patterning using a simplified re-epithelialization model of wound tissue. Our results suggest that biochemical cues are better at guiding cell migration with improved directionality and persistence, while mechanical cues are better at coordinating collective cell migration. Overall, DyCelFEM can be used to study developmental processes when a large population of migrating cells under mechanical and biochemical controls experience complex changes in cell shapes and mechanics. © 2017 The Author(s).

  18. EBV BART MicroRNAs Target Multiple Pro-apoptotic Cellular Genes to Promote Epithelial Cell Survival.

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    Dong Kang

    2015-06-01

    Full Text Available Epstein-Barr virus (EBV is a ubiquitous human γ-herpesvirus that can give rise to cancers of both B-cell and epithelial cell origin. In EBV-induced cancers of epithelial origin, including nasopharyngeal carcinomas (NPCs and gastric carcinomas, the latent EBV genome expresses very high levels of a cluster of 22 viral pre-miRNAs, called the miR-BARTs, and these have previously been shown to confer a degree of resistance to pro-apoptotic drugs. Here, we present an analysis of the ability of individual miR-BART pre-miRNAs to confer an anti-apoptotic phenotype and report that five of the 22 miR-BARTs demonstrate this ability. We next used photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP to globally identify the mRNA targets bound by these miR-BARTs in latently infected epithelial cells. This led to the identification of ten mRNAs encoding pro-apoptotic mRNA targets, all of which could be confirmed as valid targets for the five anti-apoptotic miR-BARTs by indicator assays and by demonstrating that ectopic expression of physiological levels of the relevant miR-BART in the epithelial cell line AGS resulted in a significant repression of the target mRNA as well as the encoded protein product. Using RNA interference, we further demonstrated that knockdown of at least seven of these cellular miR-BART target transcripts phenocopies the anti-apoptotic activity seen upon expression of the relevant EBV miR-BART miRNA. Together, these observations validate previously published reports arguing that the miR-BARTs can exert an anti-apoptotic effect in EBV-infected epithelial cells and provide a mechanistic explanation for this activity. Moreover, these results identify and validate a substantial number of novel mRNA targets for the anti-apoptotic miR-BARTs.

  19. Jurkat cell proliferation is suppressed by Chlamydia (Chlamydophila) pneumoniae infection accompanied with attenuation of phosphorylation at Thr389 of host cellular p70S6K.

    Science.gov (United States)

    Hirai, Itaru; Ebara, Megumi; Nakanishi, Shoko; Yamamoto, Chihiro; Sasaki, Tadahiro; Ikuta, Kazuyoshi; Yamamoto, Yoshimasa

    2013-04-01

    Chlamydia (Chlamydophila) pneumoniae infects T lymphocytes and multiplies within them. Our previous studies have indicated that C. pneumoniae infection suppresses proliferation of peripheral blood mononuclear cells stimulated with Staphylococcus-enterotoxin B; however, the mechanism of suppression was unclear. In this study, we explored the molecular mechanism involved in C. pneumoniae infection by using human acute T cell leukemia cell line, Jurkat E6-1. Proliferation of Jurkat cells was suppressed in an m.o.i.-dependent manner by C. pneumoniae infection. The suppression by the infection was particularly evident during the initial 24h of the infection, and down modulation of cyclin D3 protein levels were observed at the same time period by immunoblot analysis. The suppression of the Jurkat cell proliferation and the down modulation of cyclin D3 protein level were only induced by viable C. pneumoniae infection, not by exposure to UV-killed or heat-killed C. pneumoniae. Phosphorylations at Thr308 and Ser473 of AKT were induced by C. pneumoniae infection; however, phosphorylation at Thr389 of the downstream kinase, p70S6K was inhibited by unidentified mechanism associated with C. pneumoniae infection. Taking into account that G1 arrest of the C. pneumoniae infected Jurkat cells were not observed and that p70S6K is one of the most important regulators of protein synthesis, it was suggested that the suppression of Jurkat cell proliferation by C. pneumoniae was at least in part mediated by down modulation of protein synthesis through attenuation of Thr389 phosphorylation of p70S6K. Copyright © 2012 Elsevier GmbH. All rights reserved.

  20. Cleavage of E-Cadherin by Matrix Metalloproteinase-7 Promotes Cellular Proliferation in Nontransformed Cell Lines via Activation of RhoA

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    Conor C. Lynch

    2010-01-01

    Full Text Available Perturbations in cell-cell contact machinery occur frequently in epithelial cancers and result in increased cancer cell migration and invasion. Previously, we demonstrated that MMP-7, a protease implicated in mammary and intestinal tumor growth, can process the adherens junction component E-cadherin. This observation leads us to test whether MMP-7 processing of E-cadherin could directly impact cell proliferation in nontransformed epithelial cell lines (MDCK and C57MG. Our goal was to investigate the possibility that MMP-7 produced by cancer cells may have effects on adjacent normal epithelium. Here, we show that MMP-7 processing of E-cadherin mediates, (1 loss of cell-cell contact, (2 increased cell migration, (3 a loss of epithelial cell polarization and (4 increased cell proliferation via RhoA activation. These data demonstrate that MMP-7 promotes epithelial cell proliferation via the processing of E-cadherin and provide insights into the molecular mechanisms that govern epithelial cell growth.

  1. FBXW7/hCDC4 controls glioma cell proliferation in vitro and is a prognostic marker for survival in glioblastoma patients

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    Hagedorn Martin

    2007-02-01

    Full Text Available Abstract Background In the quest for novel molecular mediators of glioma progression, we studied the regulation of FBXW7 (hCDC4/hAGO/SEL10, its association with survival of patients with glioblastoma and its potential role as a tumor suppressor gene in glioma cells. The F-box protein Fbxw7 is a component of SCFFbxw7, a Skp1-Cul1-F-box E3 ubiquitin ligase complex that tags specific proteins for proteasome degradation. FBXW7 is mutated in several human cancers and functions as a haploinsufficient tumor suppressor in mice. Any of the identified targets, Cyclin E, c-Myc, c-Jun, Notch1/4 and Aurora-A may have oncogenic properties when accumulated in tumors with FBXW7 loss. Results We tested the expression of FBXW7 in human glioma biopsies by quantitative PCR and compared the transcript levels of grade IV glioma (glioblastoma, G-IV with those of grade II tumors (G-II. In more than 80% G-IV, expression of FBXW7 was significantly reduced. In addition, levels of FBXW7 were correlated with survival indicating a possible implication in tumor aggressiveness. Locus 4q31.3 which carries FBXW7 was investigated by in situ hybridization on biopsy touchprints. This excluded allelic loss as the principal cause for low expression of FBXW7 in G-IV tumors. Two targets of Fbxw7, Aurora-A and Notch4 were preferentially immunodetected in G-IV biopsies. Next, we investigated the effects of FBXW7 misregulation in glioma cells. U87 cells overexpressing nuclear isoforms of Fbxw7 lose the expression of the proliferation markers PCNA and Ki-67, and get counterselected in vitro. This observation fits well with the hypothesis that Fbxw7 functions as a tumor suppressor in astroglial cells. Finally, FBXW7 knockdown in U87 cells leads to defects in mitosis that may promote aneuploidy in progressing glioma. Conclusion Our results show that FBXW7 expression is a prognostic marker for patients with glioblastoma. We suggest that loss of FBXW7 plays an important role in glioma

  2. Effects of insulin analogs and glucagon-like peptide-1 receptor agonists on proliferation and cellular energy metabolism in papillary thyroid cancer

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    He L

    2017-11-01

    Full Text Available Liang He,1,* Siliang Zhang,2,* Xiaowen Zhang,3 Rui Liu,2 Haixia Guan,2 Hao Zhang1 1Department of Thyroid Surgery, The First Hospital of China Medical University, Shenyang, Liaoning, 2Department of Endocrinology and Metabolism, The Endocrine Institute and The Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Hospital of China Medical University, Shenyang, Liaoning, 3Department of Endocrinology and Metabolism, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, People’s Republic of China *These authors contributed equally to this work Purpose: This study was aimed to investigate the expressions of the insulin receptor (IR, insulin-like growth factor receptor (IGF-1R, and glucagon-like peptide-1 receptor (GLP-1R in normal thyroid tissue, papillary thyroid cancer (PTC tissues, and PTC cells, and to examine the possible role of insulin analogs and GLP-1R agonists in cell proliferation and energy metabolism in PTC cells.Methods: The expressions of IR, IGF-1R, and GLP-1R in PTC tissues and PTC cell lines were detected by immunohistochemistry and western blotting, respectively. Cell proliferation was evaluated by the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay. Levels of members of the phosphoinositol-3 kinase/AKT serine/threonine kinase (Akt and mitogen-activated protein kinase/extracellular signal-regulated kinase (Erk signaling pathways were measured by western blotting. Energy metabolism of PTC cell lines was analyzed using a Seahorse Extracellular Flux analyzer.Results: Three receptors could be detected in both PTC tissues and PTC cell lines. Expressions of IGF-1R and GLP-1R were more obvious in PTC than in normal thyroid cells. Neither insulin, four insulin analogs, and two GLP-1R agonists showed significant effects on the proliferation of PTC cells, nor did they influence the levels of Akt/p-Akt and Erk/p-Erk. None of these antidiabetic agents could change the mitochondrial

  3. Differences in p53 status significantly influence the cellular response and cell survival to 1,25-dihydroxyvitamin D3-metformin cotreatment in colorectal cancer cells.

    Science.gov (United States)

    Abu El Maaty, Mohamed A; Strassburger, Wendy; Qaiser, Tooba; Dabiri, Yasamin; Wölfl, Stefan

    2017-11-01

    Mutations in the tumor suppressor p53 are highly prevalent in cancers and are known to influence the sensitivity of cells to various chemotherapeutics including the anti-cancer candidates 1,25-dihydrovitamin D3 [1,25D3] and metformin. Previous studies have demonstrated additive/synergistic anti-cancer effects of the 1,25D3-metformin combination in different models, however, the influence of p53 status on the efficacy of this regimen has not been investigated. The CRC colorectal cancer (CRC) cell lines HCT116 wild-type (wt), HCT116 p53-/-, and HT-29 (mutant; R273H) were employed, covering three different p53 variations. Synergistic effects of the combination were confirmed in all cell lines using MTT assay. Detailed evaluation of the combination's effects was performed, including on-line measurements of cellular metabolism (glycolysis/respiration) using a biosensor chip system, analyses of mitochondrial activity (membrane potential and ATP/ROS production), mRNA expression analysis of WNT/β-catenin pathway players, and a comprehensive proteomic screen using immunoblotting and ELISA microarrays. AMPK signaling was found to be more strongly induced in response to all treatments in HCT116 wt cells compared to other cell lines, an observation that was coupled to a stronger accumulation of intracellular ROS in response to metformin/combination, and finally an induction in autophagy, depicted by an increase in LC3II:LC3I ratio in combination-treated cells compared to mono-treatments. An induction in apoptotic signaling was observed in the other cell lines in response to the combination, illustrated by a decrease in expression of pro-survival Bcl2 family members. P53 status impacts cellular responses to the combination but does not hamper its anti-proliferative synergy. © 2017 Wiley Periodicals, Inc.

  4. Binding of sFRP-3 to EGF in the extra-cellular space affects proliferation, differentiation and morphogenetic events regulated by the two molecules.

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    Raffaella Scardigli

    Full Text Available BACKGROUND: sFRP-3 is a soluble antagonist of Wnts, widely expressed in developing embryos. The Wnt gene family comprises cysteine-rich secreted ligands that regulate cell proliferation, differentiation, organogenesis and oncogenesis of different organisms ranging from worms to mammals. In the canonical signal transduction pathway Wnt proteins bind to the extracellular domain of Frizzled receptors and consequently recruit Dishevelled (Dsh to the cell membrane. In addition to Wnt membrane receptors belonging to the Frizzled family, several other molecules have been described which share homology in the CRD domain and lack the putative trans-membrane domain, such as sFRP molecules (soluble Frizzled Related Protein. Among them, sFRP-3 was originally isolated from bovine articular cartilage and also as a component of the Spemann organizer. sFRP-3 blocks Wnt-8 induced axis duplication in Xenopus embryos and binds to the surface of cells expressing a membrane-anchored form of Wnt-1. Injection of sFRP-3 mRNA blocks expression of XMyoD mRNA and leads to embryos with enlarged heads and shortened trunks. METHODOLOGY/PRINCIPAL FINDINGS: Here we report that sFRP-3 specifically blocks EGF-induced fibroblast proliferation and foci formation. Over-expression of sFRP-3 reverts EGF-mediated inhibition of hair follicle development in the mouse ectoderm while its ablation in Xenopus maintains EGF-mediated inhibition of ectoderm differentiation. Conversely, over-expression of EGF reverts the inhibition of somitic myogenesis and axis truncation in Xenopus and mouse embryos caused by sFRP-3. In vitro experiments demonstrated a direct binding of EGF to sFRP-3 both on heparin and on the surface of CHO cells where the molecule had been membrane anchored. CONCLUSIONS/SIGNIFICANCE: sFRP-3 and EGF reciprocally inhibit their effects on cell proliferation, differentiation and morphogenesis and indeed are expressed in contiguous domains of the embryo, suggesting that in

  5. Basic Fibroblast Growth Factor Inhibits Apoptosis and Promotes Proliferation of Adipose-Derived Mesenchymal Stromal Cells Isolated from Patients with Type 2 Diabetes by Reducing Cellular Oxidative Stress

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    Daria Nawrocka

    2017-01-01

    Full Text Available Type 2 diabetes (T2D is a chronic metabolic disorder affecting increasing number of people in developed countries. Therefore new strategies for treatment of T2D and its complications are of special interest. Nowadays, cellular therapies involving mesenchymal stromal cells that reside in adipose tissue (ASCs constitute a promising approach; however, there are still many obstacles concerning safety and effectiveness that need to be overcome before ASCs could be engaged for the treatment of diabetes mellitus. One of the challenges is preventing ASCs from deterioration caused by elevated oxidative stress present in diabetes milieu. In the current study we investigated the effect of basic fibroblast growth factor (bFGF treatment on ASCs isolated from patients with diagnosed T2D. We demonstrate here that cell exposition to bFGF in 5 and 10 ng/mL dosages results in improved morphology, increased proliferative activity, reduced cellular senescence and apoptosis, and decreased oxidative stress, indicating recovery of ASCs’ function impaired by T2D. Therefore our results provide a support for bFGF as a potential therapeutic agent for improving stem cell-based approaches for the treatment of diabetes mellitus and its complications.

  6. Bioaugmentation with GFP-Tagged Pseudomonas migulae AN-1 in Aniline-Contaminated Aquifer Microcosms: Cellular Responses, Survival and Effect on Indigenous Bacterial Community.

    Science.gov (United States)

    Zhao, Yongsheng; Qu, Dan; Zhou, Rui; Ma, Yunge; Wang, Hao; Ren, Hejun

    2016-05-28

    The recently isolated aniline-degrading bacterium Pseudomonas migulae AN-1 was tagged with green fluorescent protein (GFP) to investigate its bioaugmentation potential against anilinecontaminated groundwater through microcosm experiments. The survival and cellular response of GFP-tagged AN-1 introduced in a lab-scale aquifer corresponded directly with aniline consumption. During the process, the GFP-tagged AN-1 biomass increased from 7.52 × 10⁵ cells/ml to 128 × 10⁵ cells/ml and the degradation rate of aniline was 6.04 mg/l/h. GFP-tagged AN-1 was moderately hydrophobic (41.74%-47.69%) when treated with 20- 100 mg/l aniline and exhibited relatively strong hydrophobicity (55.25%-65.78%) when the concentration of aniline was ≥100 mg/l. The membrane permeability of AN-1 increased followed by a rise in aniline below 100 mg/l and was invariable with aniline above 100 mg/l. Pyrosequencing analysis showed that the relative abundance of Proteobacteria (accounted for 99.22% in the non-bioaugmentation samples) changed to 89.23% after bioaugmentation with GFP-tagged AN-1. Actinobacteria increased from 0.29% to 2.01%, whereas the abundance of Firmicutes barely changed. These combined findings demonstrate the feasibility of removing aniline in aquifers by introducing the strain AN-1 and provide valuable information on the changes in the diversity of dominant populations during bioaugmentation.

  7. Orally administered indomethacin acutely reduces cellular prion protein in the small intestine and modestly increases survival of mice exposed to infectious prions.

    Science.gov (United States)

    Martin, Gary R; Sharkey, Keith A; Jirik, Frank R

    2015-05-01

    The oral uptake of infectious prions represents a common way to acquire a prion disease; thus, host factors, such as gut inflammation and intestinal "leakiness", have the potential to influence infectivity. For example, the ingestion of nonsteroidal anti-inflammatory drugs (NSAIDs) is known to induce intestinal inflammation and increase intestinal permeability. Previously, we reported that normal cellular prion protein (PrP(C)) expression was increased in experimental colitis, and since the level of PrP(C) expressed is a determinant of prion disease propagation, we hypothesized that NSAID administration prior to the oral inoculation of mice with infectious prions would increase intestinal PrP(C) expression and accelerate the onset of neurological disease. In the long-term experiments, one group of mice was gavaged with indomethacin, followed by a second gavage with brain homogenate containing mouse-adapted scrapie (ME7). Control mice received ME7 brain homogenate alone. Brain and splenic tissues were harvested at several time points for immunoblotting, including at the onset of clinical signs of disease. In a second series of experiments, mice were gavaged with indomethacin to assess the acute effects of this treatment on intestinal PrP(C) expression. Acutely, NSAID treatment reduced intestinal PrP(C) expression, and chronically, there was a modest delay in the onset of neurological disease. In contrast to our hypothesis, brief exposure to an NSAID decreased intestinal PrP(C) expression and led to a modest survival advantage following oral ingestion of infectious prions.

  8. E2F1-mediated upregulation of p19INK4d determines its periodic expression during cell cycle and regulates cellular proliferation.

    Directory of Open Access Journals (Sweden)

    Abel L Carcagno

    Full Text Available BACKGROUND: A central aspect of development and disease is the control of cell proliferation through regulation of the mitotic cycle. Cell cycle progression and directionality requires an appropriate balance of positive and negative regulators whose expression must fluctuate in a coordinated manner. p19INK4d, a member of the INK4 family of CDK inhibitors, has a unique feature that distinguishes it from the remaining INK4 and makes it a likely candidate for contributing to the directionality of the cell cycle. p19INK4d mRNA and protein levels accumulate periodically during the cell cycle under normal conditions, a feature reminiscent of cyclins. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we demonstrate that p19INK4d is transcriptionally regulated by E2F1 through two response elements present in the p19INK4d promoter. Ablation of this regulation reduced p19 levels and restricted its expression during the cell cycle, reflecting the contribution of a transcriptional effect of E2F1 on p19 periodicity. The induction of p19INK4d is delayed during the cell cycle compared to that of cyclin E, temporally separating the induction of these proliferative and antiproliferative target genes. Specific inhibition of the E2F1-p19INK4d pathway using triplex-forming oligonucleotides that block E2F1 binding on p19 promoter, stimulated cell proliferation and increased the fraction of cells in S phase. CONCLUSIONS/SIGNIFICANCE: The results described here support a model of normal cell cycle progression in which, following phosphorylation of pRb, free E2F induces cyclin E, among other target genes. Once cyclinE/CDK2 takes over as the cell cycle driving kinase activity, the induction of p19 mediated by E2F1 leads to inhibition of the CDK4,6-containing complexes, bringing the G1 phase to an end. This regulatory mechanism constitutes a new negative feedback loop that terminates the G1 phase proliferative signal, contributing to the proper coordination of the cell

  9. Identification of intermediate risk breast cancer patients with 1-3 positive lymph nodes and excellent survival after tamoxifen as only systemic adjuvant therapy by use of markers of proliferation and apoptosis.

    Science.gov (United States)

    Linderholm, B K; Linder, S; Arnesson, L-G; Stål, O

    2013-10-01

    According to current guidelines, patients with primary breast cancer and 1-3 lymph node metastases will in general be offered adjuvant chemotherapy. Our objective was to investigate the relationship between markers of proliferation and apoptosis with survival for patients subjected to adjuvant tamoxifen solely. Tumour cytosol samples from 409 consecutive patients with operable oestrogen receptor positive BC, stage I-III and treated with tamoxifen for 2 or 5 years were assessed for levels of caspase-cleaved cytokeratin-18 (ccCK18), an indicator of apoptosis, by use of an ELISA assay. Data on S-phase fraction (SPF) were available for 370 patients. Survival analyses were performed according to levels of ccCK18 and SPF separately, as well as combined. A wide range of ccCK18 protein levels was found, median 9.97, range 0.0-87.3 pg/μgDNA. Increasing SPFs were significantly associated with a lower distant recurrence-free survival (DRFS) (p = 0.025) and breast cancer survival (BCS) (p = 0.046). In the group with low SPF (below mean), low amounts of ccCK/18 correlated with a shorter DRFS (p = 0.0028) and BCS (p = 0.0027). A Proliferation Index (PI); a quotient of ccCK18/SPF was constructed. Low PI (high ccCK18/SPF ratios) were significantly correlated with an improved survival both when analysed as continuous variables; DRFS (p = 0.021), BCS (p = 0.038) and when divided into quartiles; DRFS (p < 0.001) and BCS (p = 0.0012). A similar correlation was found in patients with 1-3 lymph node metastases; DRFS (p = 0.089) and BCS (p = 0.019). A Cox's proportional hazard model including age, tumour size, lymph node status, PgR and ccCK18/SPF was used for multivariate analysis. High ccCK18/SPF ratios correlated with improved survival; DRFS (HR = 0.47 (0.22-0.98), p = 0.043), and BCS (HR = 0.39 (0.16-1.00), p = 0.049), respectively. By use of a proliferation index based on markers of proliferation and apoptosis, a group of patients with 1-3 lymph node metastases with good outcome

  10. Early differential cell death and survival mechanisms initiate and contribute to the development of OPIDN: A study of molecular, cellular, and anatomical parameters

    Energy Technology Data Exchange (ETDEWEB)

    Damodaran, T.V., E-mail: tdamodar@nccu.edu [Dept of Medicine, Duke University Medical Center, Durham, NC (United States); Pharmacology and Cancer biology, Duke University Medical Center, Durham, NC (United States); Dept of Biology, North Carolina Central University, Durham, NC 27707 (United States); Attia, M.K. [Pharmacology and Cancer biology, Duke University Medical Center, Durham, NC (United States); Abou-Donia, M.B., E-mail: donia@mc.duke.edu [Pharmacology and Cancer biology, Duke University Medical Center, Durham, NC (United States)

    2011-11-15

    analysis revealed that the order of severity of damage declines from the spino-cerebellar, ventral, and dorsal tract respectively, suggesting neuroanatomical specificity. Thus, early activation of cell death and cell survival processes may play significant role in the clinical progression and syndromic clinical feature presentation of OPIDN. -- Highlights: Black-Right-Pointing-Pointer Multiple mechanisms of neurodegeneration were indicated in a study on OPIDN model. Black-Right-Pointing-Pointer Altered expressions of BCL2 and GADD45 were recorded in various tissues of CNS. Black-Right-Pointing-Pointer Multiple anomalous cellular (neuronal and astroglial) features were recorded. Black-Right-Pointing-Pointer Anatomical specificity of the neurodegeneration was described.

  11. Strong anti-Epstein Barr virus (EBV) or cytomegalovirus (CMV) cellular immune responses predict survival and a favourable response to anti-tuberculosis therapy.

    Science.gov (United States)

    Nagu, Tumaini; Aboud, Said; Rao, Martin; Matee, Mecky; Axelsson, Rebecca; Valentini, Davide; Mugusi, Ferdinand; Zumla, Alimuddin; Maeurer, Markus

    2017-03-01

    Intact immune responses to cytomegalovirus (CMV) and Epstein-Barr virus (EBV) represent a biologically and clinically relevant correlate of 'immunological fitness' in humans. However, there is a lack of knowledge concerning anti-EBV or anti-CMV responses in patients with pulmonary tuberculosis (TB), in whom aberrant immune responses may promote progression of clinical disease. Venous blood samples were obtained at the time of (sputum smear positive) pulmonary TB diagnosis. A whole blood assay was performed by exposing PBMCs (peripheral blood mononuclear cells) to a panel of infectious antigens, including CMV, EBV and mycobacterial proteins. Cell culture supernatants were collected after seven days and interferon gamma (IFN-γ) was measured using a sandwich ELISA. Patients received standard first line anti-tuberculosis rifampicin (R)/isoniazid (H)/ethambutol (E)/pyrazinamide (Z) for two months followed by RH for four months. PBMCs from cured patients (after treatment completion) exhibited significantly stronger IFN-γ responses to CMV (p=0.035), EBV (p=0.006) or Mycobacterium tuberculosis ESAT-6 (p=0.043) at the time of diagnosis as compared to patients who succumbed to TB during treatment. IFN-γ responses to other viral (H5N1, HSV-1) as well as other mycobacterial (Ag85A, Rv2958c, Rv0447c) antigens were not found to be significantly different among patients who were cured or those who succumbed to TB. Increased cellular immune responses to CMV and EBV antigens at the time of diagnosis of pulmonary tuberculosis are associated with increased survival after a standard six months anti-TB therapy. CVM and EBV antigens may represent "intrinsic markers for immune fitness" and guide improved TB therapies including host-directed therapies. Copyright © 2017. Published by Elsevier Ltd.

  12. Cell proliferation and survival mechanisms underlying the abnormal persistence of follicular cysts in bovines with cystic ovarian disease induced by ACTH.

    Science.gov (United States)

    Salvetti, Natalia R; Stangaferro, Matías L; Palomar, Martín M; Alfaro, Natalia S; Rey, Florencia; Gimeno, Eduardo J; Ortega, Hugo H

    2010-10-01

    Cystic ovarian disease (COD) is an important cause of infertility that affects cattle. Alterations in the ovarian micro-environment of females with follicular cysts could alter the normal processes of proliferation and programmed cell death in ovarian cells. Thus, the objective in the present study was to evaluate apoptosis and proliferation in induced ovarian cystic follicles in cows to investigate the follicular persistence. Stage of estrous cycle was synchronized in 10 heifers and 5 were then subjected to the induction of COD by administration of ACTH. After the ovariectomy number of in situ apoptotic cells by TUNEL assay, active caspase-3, FAS/FASLG and members of the BCL2 family were compared by immunohistochemistry and multiplex PCR and cell proliferation by evaluation of Ki-67 protein and cyclin D1 and E mRNA. Significantly (pfollicular cysts and related diseases. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Glutamate Increases In Vitro Survival and Proliferation and Attenuates Oxidative Stress-Induced Cell Death in Adult Spinal Cord-Derived Neural Stem/Progenitor Cells via Non-NMDA Ionotropic Glutamate Receptors.

    Science.gov (United States)

    Hachem, Laureen D; Mothe, Andrea J; Tator, Charles H

    2016-08-15

    Traumatic spinal cord injury (SCI) leads to a cascade of secondary chemical insults, including oxidative stress and glutamate excitotoxicity, which damage host neurons and glia. Transplantation of exogenous neural stem/progenitor cells (NSPCs) has shown promise in enhancing regeneration after SCI, although survival of transplanted cells remains poor. Understanding the response of NSPCs to the chemical mediators of secondary injury is essential in finding therapies to enhance survival. We examined the in vitro effects of glutamate and glutamate receptor agonists on adult rat spinal cord-derived NSPCs. NSPCs isolated from the periventricular region of the adult rat spinal cord were exposed to various concentrations of glutamate for 96 h. We found that glutamate treatment (500 μM) for 96 h significantly increased live cell numbers, reduced cell death, and increased proliferation, but did not significantly alter cell phenotype. Concurrent glutamate treatment (500 μM) in the setting of H2O2 exposure (500 μM) for 10 h increased NSPC survival compared to H2O2 exposure alone. The effects of glutamate on NSPCs were blocked by the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate receptor antagonist GYKI-52466, but not by the N-methyl-D-aspartic acid receptor antagonist MK-801 or DL-AP5, or the mGluR3 antagonist LY-341495. Furthermore, treatment of NSPCs with AMPA, kainic acid, or the kainate receptor-specific agonist (RS)-2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl)propanoic acid mimicked the responses seen with glutamate both alone and in the setting of oxidative stress. These findings offer important insights into potential mechanisms to enhance NSPC survival and implicate a potential role for glutamate in promoting NSPC survival and proliferation after traumatic SCI.

  14. The Cooperative Effect of Genistein and Protein Hydrolysates on the Proliferation and Survival of Osteoblastic Cells (hFOB 1.19

    Directory of Open Access Journals (Sweden)

    Shuo Wang

    2016-11-01

    Full Text Available Chum salmon skin gelatin, de-isoflavoned soy protein, and casein were hydrolyzed at two degrees of hydrolysis. Genistein, the prepared hydrolysates, and genistein-hydrolysate combinations were assessed for their proliferative and anti-apoptotic effects on human osteoblasts (hFOB 1.19 to clarify potential cooperative effects between genistein and these hydrolysates in these two activities. Genistein at 2.5 μg/L demonstrated the highest proliferative activity, while the higher dose of genistein inhibited cell growth. All hydrolysates promoted osteoblast proliferation by increasing cell viability to 102.9%–131.1%. Regarding etoposide- or NaF-induced osteoblast apoptosis, these hydrolysates at 0.05 g/L showed both preventive and therapeutic effects against apoptosis. In the mode of apoptotic prevention, the hydrolysates decreased apoptotic cells from 32.9% to 15.2%–23.7% (etoposide treatment or from 23.6% to 14.3%–19.6% (NaF treatment. In the mode of apoptotic rescue, the hydrolysates lessened the extent of apoptotic cells from 15.9% to 13.0%–15.3% (etoposide treatment or from 13.3% to 10.9%–12.7% (NaF treatment. Gelatin hydrolysates showed the highest activities among all hydrolysates in all cases. All investigated combinations (especially the genistein-gelatin hydrolysate combination had stronger proliferation, apoptotic prevention, and rescue than genistein itself or their counterpart hydrolysates alone, suggesting that genistein cooperated with these hydrolysates, rendering greater activities in osteoblast proliferation and anti-apoptosis.

  15. UVB-induced nuclear translocation of TC-PTP by AKT/14-3-3σ axis inhibits keratinocyte survival and proliferation.

    Science.gov (United States)

    Kim, Mihwa; Morales, Liza D; Baek, Minwoo; Slaga, Thomas J; DiGiovanni, John; Kim, Dae Joon

    2017-10-31

    Understanding protein subcellular localization is important to determining the functional role of specific proteins. T-cell protein tyrosine phosphatase (TC-PTP) contains bipartite nuclear localization signals (NLSI and NLSII) in its C-terminus. We previously have demonstrated that the nuclear form of TC-PTP (TC45) is mainly localized to the cytoplasm in keratinocytes and it is translocated to the nucleus following UVB irradiation. Here, we report that TC45 is translocated by an AKT/14-3-3σ-mediated mechanism in response to UVB exposure, resulting in increased apoptosis and decreased keratinocyte proliferation. We demonstrate that UVB irradiation increased phosphorylation of AKT and induced nuclear translocation of 14-3-3σ and TC45. However, inhibition of AKT blocked nuclear translocation of TC45 and 14-3-3σ. Site-directed mutagenesis of 14-3-3σ binding sites within TC45 showed that a substitution at Threonine 179 (TC45/T179A) effectively blocked UVB-induced nuclear translocation of ectopic TC45 due to the disruption of the direct binding between TC45 and 14-3-3σ. Overexpression of TC45/T179A in keratinocytes resulted in a decrease of UVB-induced apoptosis which corresponded to an increase in nuclear phosphorylated STAT3, and cell proliferation was higher in TC45/T179A-overexpressing keratinocytes compared to control keratinocytes following UVB irradiation. Furthermore, deletion of TC45 NLSII blocked its UVB-induced nuclear translocation, indicating that both T179 and NLSII are required. Taken together, our findings suggest that AKT and 14-3-3σ cooperatively regulate TC45 nuclear translocation in a critical step of an early protective mechanism against UVB exposure that signals the deactivation of STAT3 in order to promote keratinocyte cell death and inhibit keratinocyte proliferation.

  16. Cigarette smoke extract promotes human vascular smooth muscle cell proliferation and survival through ERK1/2- and NF-κB-dependent pathways

    DEFF Research Database (Denmark)

    Chen, Qing-Wen; Edvinsson, Lars; Xu, Cang-Bao

    2010-01-01

    Tobacco use is one of the major risk factors of cardiovascular disease. The underlying molecular mechanisms that link cigarette smoke to cardiovascular disease remain unclear. The present study was designed to examine the effects of dimethyl sulfoxide (DMSO)-soluble smoke particles (DSPs) on human...... and necrosis were found in serum-starved HASMCs. DSPs decreased cell death and increased B-cell leukemia/lymphoma 2 expression. Blocking phosphorylation of ERK1/2 or NF-κB attenuated DSP-induced cell death inhibition. Cigarette smoke particles stimulate HASMC proliferation and inhibit cell death...

  17. Cigarette smoke extract promotes human vascular smooth muscle cell proliferation and survival through ERK1/2- and NF-κB-dependent pathways

    DEFF Research Database (Denmark)

    Chen, Qing-Wen; Edvinsson, Lars; Xu, Cang-Bao

    2010-01-01

    Tobacco use is one of the major risk factors of cardiovascular disease. The underlying molecular mechanisms that link cigarette smoke to cardiovascular disease remain unclear. The present study was designed to examine the effects of dimethyl sulfoxide (DMSO)-soluble smoke particles (DSPs) on human...... and necrosis were found in serum-starved HASMCs. DSPs decreased cell death and increased B-cell leukemia/lymphoma 2 expression. Blocking phosphorylation of ERK1/2 or NF-¿B attenuated DSP-induced cell death inhibition. Cigarette smoke particles stimulate HASMC proliferation and inhibit cell death...

  18. Effect of the herbicide Roundup on Perkinsus olseni in vitro proliferation and in vivo survival when infecting a permissive host, the clam Ruditapes decussatus.

    Science.gov (United States)

    Elandalloussi, L M; Leite, R B; Rodrigues, P M; Afonso, R; Cancela, M L

    2008-06-01

    Coastal habitats are increasingly being exposed to herbicide contamination from urban and agricultural catchments. Data on its toxicity on aquatic ecosystems, especially those based on sediment, are relatively scarce. This study aimed at investigating whether the susceptibility of an aquatic filter-feeding organism, the carpet-shell clam (Ruditapes decussatus) to the parasite Perkinsus olseni was influenced by the herbicide Roundup and its active ingredient glyphosate. The effect of Roundup and glyphosate on P. olseni in vitro proliferation was also evaluated and appeared to confirm the higher toxicity of Roundup when compared with technical grade glyphosate.

  19. The histone H3 methyltransferase G9A epigenetically activates the serine-glycine synthesis pathway to sustain cancer cell survival and proliferation.

    Science.gov (United States)

    Ding, Jane; Li, Tai; Wang, Xiangwei; Zhao, Erhu; Choi, Jeong-Hyeon; Yang, Liqun; Zha, Yunhong; Dong, Zheng; Huang, Shuang; Asara, John M; Cui, Hongjuan; Ding, Han-Fei

    2013-12-03

    Increased activation of the serine-glycine biosynthetic pathway is an integral part of cancer metabolism that drives macromolecule synthesis needed for cell proliferation. Whether this pathway is under epigenetic control is unknown. Here we show that the histone H3 lysine 9 (H3K9) methyltransferase G9A is required for maintaining the pathway enzyme genes in an active state marked by H3K9 monomethylation and for the transcriptional activation of this pathway in response to serine deprivation. G9A inactivation depletes serine and its downstream metabolites, triggering cell death with autophagy in cancer cell lines of different tissue origins. Higher G9A expression, which is observed in various cancers and is associated with greater mortality in cancer patients, increases serine production and enhances the proliferation and tumorigenicity of cancer cells. These findings identify a G9A-dependent epigenetic program in the control of cancer metabolism, providing a rationale for G9A inhibition as a therapeutic strategy for cancer. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Changes in the cellular microRNA profile by the intracellular expression of HIV-1 Tat regulator: A potential mechanism for resistance to apoptosis and impaired proliferation in HIV-1 infected CD4+ T cells.

    Science.gov (United States)

    Sánchez-Del Cojo, María; López-Huertas, María Rosa; Díez-Fuertes, Francisco; Rodríguez-Mora, Sara; Bermejo, Mercedes; López-Campos, Guillermo; Mateos, Elena; Jiménez-Tormo, Laura; Gómez-Esquer, Francisco; Díaz-Gil, Gema; Alcamí, José; Coiras, Mayte

    2017-01-01

    HIV-1 induces changes in the miRNA expression profile of infected CD4+ T cells that could improve viral replication. HIV-1 regulator Tat modifies the cellular gene expression and has been appointed as an RNA silencing suppressor. Tat is a 101-residue protein codified by two exons that regulates the elongation of viral transcripts. The first exon of Tat (amino acids 1-72) forms the transcriptionally active protein Tat72, but the presence of the second exon (amino acids 73-101) results in a more competent regulatory protein (Tat101) with additional functions. Intracellular, full-length Tat101 induces functional and morphological changes in CD4+ T cells that contribute to HIV-1 pathogenesis such as delay in T-cell proliferation and protection against FasL-mediated apoptosis. But the precise mechanism by which Tat produces these changes remains unknown. We analyzed how the stable expression of intracellular Tat101 and Tat72 modified the miRNA expression profile in Jurkat cells and if this correlated with changes in apoptotic pathways and cell cycle observed in Tat-expressing cells. Specifically, the enhanced expression of hsa-miR-21 and hsa-miR-222 in Jurkat-Tat101 cells was associated with the reduced expression of target mRNAs encoding proteins related to apoptosis and cell cycle such as PTEN, PDCD4 and CDKN1B. We developed Jurkat cells with stable expression of hsa-miR-21 or hsa-miR-222 and observed a similar pattern to Jurkat-Tat101 in resistance to FasL-mediated apoptosis, cell cycle arrest in G2/M and altered cell morphology. Consequently, upregulation of hsa-miR-21 and hsa-miR-222 by Tat may contribute to protect against apoptosis and to anergy observed in HIV-infected CD4+ T cells.

  1. The Effects of kisspeptin-10 on Migration and Proliferation of Endothelial Cell

    Directory of Open Access Journals (Sweden)

    Fatemeh Golzar

    2015-01-01

    Full Text Available Background: Migration, expansion and survival of endothelial cells that are an important cellular component of blood vessels plays an important role in the induction of tumor growth. Kisspeptins (kp, peptides that bind to coupled-G protein receptor (GPR54, inhibit each step of metastatic cascade include invasion, migration and homing, angiogenesis, survival and proliferation. In this study we investigated effects of kisspeptin-10, the most potent member of kisspeptin family, on Migration and proliferation of endothelial cells that are necessary for angiogenesis and tumor metastasis. Materials and Methods: We compared migration of Human Umbilical Vein Endothelial Cells (HUVECs were treated with 10-100 or 500 nM kp-10 for 24 hours and no treated cells using an in vitro trans membrane migration assay and HUVEC proliferation of treated endothelial cells with 10-100 or 500 nM kp-10 for 48 hours and no treated cells was measured by MTT Cell Proliferation Assay Kit. Analysis of data was performed using the Kruskal-Wallis test followed by the Mann-Whitney test. Results: Migration and proliferation of endothelial cells were increased at lower concentration of kp-10 specially at 100 nM while higher concentration reduced both migration and proliferation. Conclusion: Our data showed that different concentrations of kp-10 have distinct effects on migration and proliferation of endothelial cells.

  2. Stem cell survival is severely compromised by the thymidineanalog EdU (5-ethynyl-2'-deoxyuridine), an alternative to BrdU for proliferation assays and stem cell tracing

    DEFF Research Database (Denmark)

    Andersen, Ditte C; Skovrind, Ida; Christensen, Marlene Louise

    2013-01-01

    Stem cell therapy has opened up the possibility of treating numerous degenerating diseases. However, we are still merely at the stage of identifying appropriate sources of stem cells and exploring their full differentiation potential. Thus, tracking the stem cells upon in vivo engraftment...... and during in vitro co-culture is very important and is an area of research embracing many pitfalls. 5-Ethynyl-2'-deoxyuridine (EdU), a rather new thymidine analog incorporated into DNA, has recently been suggested to be a novel highly valid alternative to other dyes for labeling of stem cells and subsequent...... tracing of their proliferation and differentiation ability. However, our results herein do not at any stage support this recommendation, since EdU severely reduces the viability of stem cells. Accordingly, we found that transplanted EdU-labeled stem cells hardly survive upon in vivo transplantation...

  3. Expression of p89c-Mybex9b, an alternatively spliced form of c-Myb, is required for proliferation and survival of p210BCR/ABL-expressing cells

    Science.gov (United States)

    Manzotti, G; Mariani, S A; Corradini, F; Bussolari, R; Cesi, V; Vergalli, J; Ferrari-Amorotti, G; Fragliasso, V; Soliera, A R; Cattelani, S; Raschellà, G; Holyoake, T L; Calabretta, B

    2012-01-01

    The c-Myb gene encodes the p75c-Myb isoform and less-abundant proteins generated by alternatively spliced transcripts. Among these, the best known is pc-Mybex9b, which contains 121 additional amino acids between exon 9 and 10, in a domain involved in protein–protein interactions and negative regulation. In hematopoietic cells, expression of pc-Mybex9b accounts for 10–15% of total c-Myb; these levels may be biologically relevant because modest changes in c-Myb expression affects proliferation and survival of leukemic cells and lineage choice and frequency of normal hematopoietic progenitors. In this study, we assessed biochemical activities of pc-Mybex9b and the consequences of perturbing its expression in K562 and primary chronic myeloid leukemia (CML) progenitor cells. Compared with p75c-Myb, pc-Mybex9b is more stable and more effective in transactivating Myb-regulated promoters. Ectopic expression of pc-Mybex9b enhanced proliferation and colony formation and reduced imatinib (IM) sensitivity of K562 cells; conversely, specific downregulation of pc-Mybex9b reduced proliferation and colony formation, enhanced IM sensitivity of K562 cells and markedly suppressed colony formation of CML CD34+ cells, without affecting the levels of p75c-Myb. Together, these studies indicate that expression of the low-abundance pc-Mybex9b isoform has an important role for the overall biological effects of c-Myb in BCR/ABL-transformed cells. PMID:22829973

  4. Lead decreases cell survival, proliferation, and neuronal differentiation of primary cultured adult neural precursor cells through activation of the JNK and p38 MAP kinases

    Science.gov (United States)

    Engstrom, Anna; Wang, Hao; Xia, Zhengui

    2015-01-01

    Adult hippocampal neurogenesis is the process whereby adult neural precursor cells (aNPCs) in the subgranular zone (SGZ) of the dentate gyrus (DG) generate adult-born, functional neurons in the hippocampus. This process is modulated by various extracellular and intracellular stimuli, and the adult-born neurons have been implicated in hippocampus-dependent learning and memory. However, studies on how neurotoxic agents affect this process and the underlying mechanisms are limited. The goal of this study was to determine whether lead, a heavy metal, directly impairs critical processes in adult neurogenesis and to characterize the underlying signaling pathways using primary cultured SGZ-aNPCs isolated from adult mice. We report here that lead significantly increases apoptosis and inhibits proliferation in SGZ-aNPCs. In addition, lead significantly impairs spontaneous neuronal differentiation and maturation. Furthermore, we found that activation of the c-Jun NH2-terminal kinase (JNK) and p38 mitogen activated protein (MAP) kinase signaling pathways are important for lead cytotoxicity. Our data suggest that lead can directly act on adult neural stem cells and impair critical processes in adult hippocampal neurogenesis, which may contribute to its neurotoxicity and adverse effects on cognition in adults. PMID:25967738

  5. The involvement of miR-100 in bladder urothelial carcinogenesis changing the expression levels of mRNA and proteins of genes related to cell proliferation, survival, apoptosis and chromosomal stability.

    Science.gov (United States)

    Morais, Denis R; Reis, Sabrina T; Viana, Nayara; Piantino, Camila Berfort; Massoco, Cristina; Moura, Caio; Dip, Nelson; Silva, Iran A; Srougi, Miguel; Leite, Katia Rm

    2014-01-01

    MicroRNAs (miRNA) are small non-coding RNAs that play an important role in the control of gene expression by inhibiting protein translation or promoting messenger RNA degradation. Today, miRNAs have been shown to be involved in various physiological and pathological cellular processes, including cancer, where they can act as oncogenes or tumor suppressor genes. Recently, lowered expression of miR-100, resulting in upregulation of FGFR3, has been correlated with low-grade, non-invasive bladder urothelial cancer, as an alternative oncogenesis pathway to the typical FGFR3 gene mutation. Our aim is to analyze the role of miR-100 in bladder cancer cell lines in controlling the expression of some of its possible target genes, including FGFR3 and its relationship with proliferation, apoptosis and DNA ploidy. The bladder cancer cell lines RT4 and T24 were transfected with pre-miR 100, anti-miR 100 and their respective controls using a lipid-based formulation. After transfection mRNA and protein levels of its supposed target genes THAP2, BAZ2A, mTOR, SMARCA5 and FGFR3 were analyzed by quantitative real time polymerase chain reaction (qRT-PCR) and western blotting. Cell proliferation, apoptosis and DNA ploidy were analyzed by flow cytometry. For statistical analysis, a t-test was applied, p RT4, mTOR (p = 0.023) and SMARCA5 (p = 0.015) in T24. There was a reduction in the expression of all proteins, variable from 22.5% to 57.1% in both cell lines. In T24 miR-100 promoted an increase in cell proliferation and anti-miR 100 promoted apoptosis characterizing miR-100 as an oncomiR in this cell line representative of a high-grade urothelial carcinoma. miR-100 transfection reduces expression of BAZ2A, mTOR and SMARCA5 mRNA and protein in BC cell lines. miR-100 would be classified as an oncomiR in T24 cells representative of high grade urothelial carcinoma promoting increase in cell proliferation and reduction in apoptosis. The knowledge of miRNA role in tumors will allow their use

  6. The novel mTORC1/2 dual inhibitor INK-128 suppresses survival and proliferation of primary and transformed human pancreatic cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Lou, Hai-zhou [Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Weng, Xiao-chuan [Department of Anesthesiology, Hangzhou Xia-sha Hospital, Hangzhou 310018 (China); Pan, Hong-ming; Pan, Qin [Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Sun, Peng [Department of Medical Oncology, Sun Yat-Sen University Cancer Center, Guangzhou 510060 (China); Liu, Li-li [Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Chen, Bin, E-mail: chenbinhangzhou126@126.com [Department of Hepatopancreatobiliary Surgery, First People’s Hospital of Hangzhou, Hangzhou 310006 (China)

    2014-07-25

    Highlights: • INK-128 inhibits the survival and growth of human pancreatic cancer cells. • INK-128 induced pancreatic cancer cell apoptosis and necrosis simultaneously. • INK-128 blocks mTORC1/2 activation simultaneously in pancreatic cancer cells. • INK-128 down-regulates cyclin D1 and causes pancreatic cancer cell cycle arrest. • INK-128 significantly increases sensitivity of pancreatic cancer cells to gemcitabine. - Abstract: Pancreatic cancer has one of worst prognosis among all human malignancies around the world, the development of novel and more efficient anti-cancer agents against this disease is urgent. In the current study, we tested the potential effect of INK-128, a novel mammalian target of rapamycin (mTOR) complex 1 and 2 (mTORC1/2) dual inhibitor, against pancreatic cancer cells in vitro. Our results demonstrated that INK-128 concentration- and time-dependently inhibited the survival and growth of pancreatic cancer cells (both primary cells and transformed cells). INK-128 induced pancreatic cancer cell apoptosis and necrosis simultaneously. Further, INK-128 dramatically inhibited phosphorylation of 4E-binding protein 1 (4E-BP1), ribosomal S6 kinase 1 (S6K1) and Akt at Ser 473 in pancreatic cancer cells. Meanwhile, it downregulated cyclin D1 expression and caused cell cycle arrest. Finally, we found that a low concentration of INK-128 significantly increased the sensitivity of pancreatic cancer cells to gemcitabine. Together, our in vitro results suggest that INK-128 might be further investigated as a novel anti-cancer agent or chemo-adjuvant for pancreatic cancer treatment.

  7. Extracellular matrix-mediated cellular communication in the heart

    Science.gov (United States)

    Valiente-Alandi, Iñigo; Schafer, Allison E.; Blaxall, Burns C.

    2016-01-01

    The extracellular matrix (ECM) is a complex and dynamic scaffold that maintains tissue structure and dynamics. However, the view of the ECM as an inert architectural support has been increasingly challenged. The ECM is a vibrant meshwork, a crucial organizer of cellular microenvironments. It plays a direct role in cellular interactions regulating cell growth, survival, spreading, proliferation, differentiation and migration through the intricate relationship among cellular and acellular tissue components. This complex interrelationship preserves cardiac function during homeostasis; however it is also responsible for pathologic remodeling following myocardial injury. Therefore, enhancing our understanding of this cross-talk may provide mechanistic insights into the pathogenesis of heart failure and suggest new approaches to novel, targeted pharmacologic therapies. This review explores the implications of ECM-cell interactions in myocardial cell behavior and cardiac function at baseline and following myocardial injury. PMID:26778458

  8. The depletion of nuclear glutathione impairs cell proliferation in 3t3 fibroblasts.

    Directory of Open Access Journals (Sweden)

    Jelena Markovic

    2009-07-01

    Full Text Available Glutathione is considered essential for survival in mammalian cells and yeast but not in prokaryotic cells. The presence of a nuclear pool of glutathione has been demonstrated but its role in cellular proliferation and differentiation is still a matter of debate.We have studied proliferation of 3T3 fibroblasts for a period of 5 days. Cells were treated with two well known depleting agents, diethyl maleate (DEM and buthionine sulfoximine (BSO, and the cellular and nuclear glutathione levels were assessed by analytical and confocal microscopic techniques, respectively. Both agents decreased total cellular glutathione although depletion by BSO was more sustained. However, the nuclear glutathione pool resisted depletion by BSO but not with DEM. Interestingly, cell proliferation was impaired by DEM, but not by BSO. Treating the cells simultaneously with DEM and with glutathione ethyl ester to restore intracellular GSH levels completely prevented the effects of DEM on cell proliferation.Our results demonstrate the importance of nuclear glutathione in the control of cell proliferation in 3T3 fibroblasts and suggest that a reduced nuclear environment is necessary for cells to progress in the cell cycle.

  9. Nitrogen anabolism underlies the importance of glutaminolysis in proliferating cells.

    Science.gov (United States)

    Meng, Meng; Chen, Shuyang; Lao, Taotao; Liang, Dongming; Sang, Nianli

    2010-10-01

    Glutaminolysis and Warburg effect are the two most noticeable metabolic features of tumor cells whereas their biological significance in cell proliferation remains elusive. A widely accepted current hypothesis is that tumor cells use glutamine as a preferred carbon source for energy and reducing power, which has been used to explain both glutaminolysis and the Warburg effect. Here we provide evidence to show that supplying nitrogen, not the carbon skeleton, underlies the major biological importance of glutaminolysis for proliferating cells. We show alternative nitrogen supplying mechanisms rescue cell proliferation in glutamine-free media. Particularly, we show that ammonia is sufficient to maintain a long-term survival and proliferation of Hep3B in glutamine-free media. We also observed that nitrogen source restriction repressed carbon metabolic pathways including glucose utilization. Based on these new observations and metabolic pathways well established in published literature, we propose an alternative model that cellular demand for glutamate as a key molecule in nitrogen anabolism is the driving force of glutaminolysis in proliferating cells. Our model suggests that the Warburg effect may be a metabolic consequence secondary to the nitrogen anabolism.

  10. Regulator of G-Protein Signaling 5 Reduces HeyA8 Ovarian Cancer Cell Proliferation and Extends Survival in a Murine Tumor Model

    Directory of Open Access Journals (Sweden)

    Molly K. Altman

    2012-01-01

    Full Text Available The regulator of G-protein signaling 5 (RGS5 belongs to a family of GTPase activators that terminate signaling cascades initiated by extracellular mediators and G-protein-coupled receptors. RGS5 has an interesting dual biological role. One functional RGS5 role is as a pericyte biomarker influencing the switch to angiogenesis during malignant progression. Its other functional role is to promote apoptosis in hypoxic environments. We set out to clarify the extent to which RGS5 expression regulates tumor progression—whether it plays a pathogenic or protective role in ovarian tumor biology. We thus constructed an inducible gene expression system to achieve RGS5 expression in HeyA8-MDR ovarian cancer cells. Through this we observed that inducible RGS5 expression significantly reduces in vitro BrdU-positive HeyA8-MDR cells, although this did not correlate with a reduction in tumor volume observed using an in vivo mouse model of ovarian cancer. Interestingly, mice bearing RGS5-expressing tumors demonstrated an increase in survival compared with controls, which might be attributed to the vast regions of necrosis observed by pathological examination. Additionally, mice bearing RGS5-expressing tumors were less likely to have ulcerated tumors. Taken together, this data supports the idea that temporal expression and stabilization of RGS5 could be a valuable tactic within the context of a multicomponent approach for modulating tumor progression.

  11. STAT3 Regulates Proliferation and Survival of CD8+ T Cells: Enhances Effector Responses to HSV-1 Infection, and Inhibits IL-10+ Regulatory CD8+ T Cells in Autoimmune Uveitis

    Directory of Open Access Journals (Sweden)

    Cheng-Rong Yu

    2013-01-01

    Full Text Available STAT3 regulates CD4+ T cell survival and differentiation. However, its effects on CD8+ T cells are not well understood. Here, we show that in comparison to WT CD8+ T cells, STAT3-deficient CD8+ T cells exhibit a preactivated memory-like phenotype, produce more IL-2, proliferate faster, and are more sensitive to activation-induced cell death (AICD. The enhanced proliferation and sensitivity to AICD correlated with downregulation of class-O forkhead transcription factors (FoxO1, FoxO3A, , , Bcl-2, OX-40, and upregulation of FasL, Bax, and Bad. We examined whether STAT3-deficient CD8+ T cells can mount effective response during herpes simplex virus (HSV-1 infection and experimental autoimmune uveitis (EAU. Compared to WT mice, HSV-1-infected STAT3-deficient mice (STAT3KO produced less IFN- and virus-specific KLRG-1+ CD8+ T cells. STAT3KO mice are also resistant to EAU and produced less IL-17-producing Tc17 cells. Resistance of STAT3KO to EAU correlated with marked expansion of IL-10-producing regulatory CD8+ T cells (CD8-Treg implicated in recovery from autoimmune encephalomyelitis. Thus, increases of IL-6-induced STAT3 activation observed during inflammation may inhibit expansion of CD8-Tregs, thereby impeding recovery from uveitis. These results suggest that STAT3 is a potential therapeutic target for upregulating CD8+ T cell-mediated responses to viruses and suggest the successful therapeutic targeting of STAT3 as treatment for uveitis, derived, in part, from promoting CD8-Treg expansion.

  12. The Clustered, Regularly Interspaced, Short Palindromic Repeats-associated Endonuclease 9 (CRISPR/Cas9)-created MDM2 T309G Mutation Enhances Vitreous-induced Expression of MDM2 and Proliferation and Survival of Cells.

    Science.gov (United States)

    Duan, Yajian; Ma, Gaoen; Huang, Xionggao; D'Amore, Patricia A; Zhang, Feng; Lei, Hetian

    2016-07-29

    The G309 allele of SNPs in the mouse double minute (MDM2) promoter locus is associated with a higher risk of cancer and proliferative vitreoretinopathy (PVR), but whether SNP G309 contributes to the pathogenesis of PVR is to date unknown. The clustered regularly interspaced short palindromic repeats (CRISPR)-associated endonuclease (Cas) 9 from Streptococcus pyogenes (SpCas9) can be harnessed to manipulate a single or multiple nucleotides in mammalian cells. Here we delivered SpCas9 and guide RNAs using dual adeno-associated virus-derived vectors to target the MDM2 genomic locus together with a homologous repair template for creating the mutation of MDM2 T309G in human primary retinal pigment epithelial (hPRPE) cells whose genotype is MDM2 T309T. The next-generation sequencing results indicated that there was 42.51% MDM2 G309 in the edited hPRPE cells using adeno-associated viral CRISPR/Cas9. Our data showed that vitreous induced an increase in MDM2 and subsequent attenuation of p53 expression in MDM2 T309G hPRPE cells. Furthermore, our experimental results demonstrated that MDM2 T309G in hPRPE cells enhanced vitreous-induced cell proliferation and survival, suggesting that this SNP contributes to the pathogenesis of PVR. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. The Clustered, Regularly Interspaced, Short Palindromic Repeats-associated Endonuclease 9 (CRISPR/Cas9)-created MDM2 T309G Mutation Enhances Vitreous-induced Expression of MDM2 and Proliferation and Survival of Cells*

    Science.gov (United States)

    Duan, Yajian; Ma, Gaoen; Huang, Xionggao; D'Amore, Patricia A.; Zhang, Feng; Lei, Hetian

    2016-01-01

    The G309 allele of SNPs in the mouse double minute (MDM2) promoter locus is associated with a higher risk of cancer and proliferative vitreoretinopathy (PVR), but whether SNP G309 contributes to the pathogenesis of PVR is to date unknown. The clustered regularly interspaced short palindromic repeats (CRISPR)-associated endonuclease (Cas) 9 from Streptococcus pyogenes (SpCas9) can be harnessed to manipulate a single or multiple nucleotides in mammalian cells. Here we delivered SpCas9 and guide RNAs using dual adeno-associated virus-derived vectors to target the MDM2 genomic locus together with a homologous repair template for creating the mutation of MDM2 T309G in human primary retinal pigment epithelial (hPRPE) cells whose genotype is MDM2 T309T. The next-generation sequencing results indicated that there was 42.51% MDM2 G309 in the edited hPRPE cells using adeno-associated viral CRISPR/Cas9. Our data showed that vitreous induced an increase in MDM2 and subsequent attenuation of p53 expression in MDM2 T309G hPRPE cells. Furthermore, our experimental results demonstrated that MDM2 T309G in hPRPE cells enhanced vitreous-induced cell proliferation and survival, suggesting that this SNP contributes to the pathogenesis of PVR. PMID:27246850

  14. Prospective Study of Serial Imaging Comparing Fluorodeoxyglucose Positron Emission Tomography (PET) and Fluorothymidine PET During Radical Chemoradiation for Non-Small Cell Lung Cancer: Reduction of Detectable Proliferation Associated With Worse Survival.

    Science.gov (United States)

    Everitt, Sarah; Ball, David; Hicks, Rodney J; Callahan, Jason; Plumridge, Nikki; Trinh, Jenny; Herschtal, Alan; Kron, Tomas; Mac Manus, Michael

    2017-11-15

    To investigate the associations between interim tumor responses on (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) and (18)F-fluorothymidine ((18)F-FLT) PET and patient outcomes, especially progression-free survival (PFS) and overall survival (OS), in non-small cell lung cancer (NSCLC) patients. Patients with FDG-PET/computed tomography stage I-III NSCLC were prescribed concurrent chemotherapy and radiation therapy (60 Gy in 30 fractions). Scans were acquired at baseline (FDG-PET/computed tomography [FDGBL] for radiation therapy planning and FLT-PET [FLTBL]), week 2 (FDGwk2 and FLTwk2), and week 4 (FDGwk4 and FLTwk4) of chemoradiation therapy. Tumor responses were categorized as complete or partial responses or stable or progressive disease (SD, PD) using European Organization for Research and Treatment of Cancer criteria. Associations between response, OS, and PFS were analyzed with univariate Cox regressions and plotted using Kaplan-Meier curves. Between 2009 and 2013, 60 patients were recruited. Thirty-seven (62%) were male, and the median age was 66 years (range, 31-86 years). Two-year OS and PFS were 0.51 and 0.26, respectively. Unexpectedly, SD on FLTwk2 compared with complete response/partial response was associated with longer OS (hazard ratio [95% confidence interval] 2.01 [0.87-4.65], P=.082) and PFS (2.01 [0.92-4.36], P=.061). Weeks 2 and 4 FDG PET/CT were not significantly associated with survival. Study scans provided additional information to FDGBL in 21 patients (35%). Distant metastases detected in 3 patients on FLTBL and in 2 patients on FDG/FLTwk2 changed treatment intent from curative to palliative. Locoregional progression during radiation therapy was observed in 5 (8%) patients, prompting larger radiation therapy fields. Stable uptake of (18)F-FLT at week 2 was paradoxically associated with longer OS and PFS. This suggests that suppression of tumor cell proliferation may protect against radiation-induced tumor cell

  15. Gemcitabine resistance in breast cancer cells regulated by PI3K/AKT-mediated cellular proliferation exerts negative feedback via the MEK/MAPK and mTOR pathways

    Directory of Open Access Journals (Sweden)

    Yang XL

    2014-06-01

    Full Text Available Xiao Li Yang, Feng Juan Lin, Ya Jie Guo, Zhi Min Shao, Zhou Luo Ou Key Laboratory of Breast Cancer in Shanghai, Breast Cancer Institute, Cancer Hospital, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China Abstract: Chemoresistance is a major cause of cancer treatment failure and leads to a reduction in the survival rate of cancer patients. Phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR and mitogen-activated protein kinase (MAPK pathways are aberrantly activated in many malignant tumors, including breast cancer, which may indicate an association with breast cancer chemoresistance. In this study, we generated a chemoresistant human breast cancer cell line, MDA-MB-231/gemcitabine (simplified hereafter as “231/Gem”, from MDA-MB-231 human breast cancer cells. Flow cytometry studies revealed that with the same treatment concentration of gemcitabine, 231/Gem cells displayed more robust resistance to gemcitabine, which was reflected by fewer apoptotic cells and enhanced percentage of S-phase cells. Through the use of inverted microscopy, Cell Counting Kit-8, and Transwell assays, we found that compared with parental 231 cells, 231/Gem cells displayed more morphologic projections, enhanced cell proliferative ability, and improved cell migration and invasion. Mechanistic studies revealed that the PI3K/AKT/mTOR and mitogen-activated protein kinase kinase (MEK/MAPK signaling pathways were activated through elevated expression of phosphorylated (p-extracellular signal-regulated kinase (ERK, p-AKT, mTOR, p-mTOR, p-P70S6K, and reduced expression of p-P38 and LC3-II (the marker of autophagy in 231/Gem in comparison to control cells. However, there was no change in the expression of Cyclin D1 and p-adenosine monophosphate-activated protein kinase (AMPK. In culture, inhibitors of PI3K/AKT and mTOR, but not of MEK/MAPK, could reverse the enhanced proliferative

  16. A Critical Role for the Peroxisome Proliferator-Activated Receptor α (PPARα) in the Cellular Fasting Response: The PPARα -Null Mouse as a Model of Fatty Acid Oxidation Disorders

    National Research Council Canada - National Science Library

    Teresa C. Leone; Carla J. Weinheimer; Daniel P. Kelly

    1999-01-01

    ...), plays a pivotal role in the cellular metabolic response to fasting. Short-term starvation caused hepatic steatosis, myocardial lipid accumulation, and hypoglycemia, with an inadequate ketogenic response in adult mice lacking PPARα (PPARα...

  17. Whole-Body Exposure to (28)Si-Radiation Dose-Dependently Disrupts Dentate Gyrus Neurogenesis and Proliferation in the Short Term and New Neuron Survival and Contextual Fear Conditioning in the Long Term.

    Science.gov (United States)

    Whoolery, Cody W; Walker, Angela K; Richardson, Devon R; Lucero, Melanie J; Reynolds, Ryan P; Beddow, David H; Clark, K Lyles; Shih, Hung-Ying; LeBlanc, Junie A; Cole, Mara G; Amaral, Wellington Z; Mukherjee, Shibani; Zhang, Shichuan; Ahn, Francisca; Bulin, Sarah E; DeCarolis, Nathan A; Rivera, Phillip D; Chen, Benjamin P C; Yun, Sanghee; Eisch, Amelia J

    2017-11-01

    Astronauts traveling to Mars will be exposed to chronic low doses of galactic cosmic space radiation, which contains highly charged, high-energy (HZE) particles. (56)Fe-HZE-particle exposure decreases hippocampal dentate gyrus (DG) neurogenesis and disrupts hippocampal function in young adult rodents, raising the possibility of impaired astronaut cognition and risk of mission failure. However, far less is known about how exposure to other HZE particles, such as (28)Si, influences hippocampal neurogenesis and function. To compare the influence of (28)Si exposure on indices of neurogenesis and hippocampal function with previous studies on (56)Fe exposure, 9-week-old C57BL/6J and Nestin-GFP mice (NGFP; made and maintained for 10 or more generations on a C57BL/6J background) received whole-body (28)Si-particle-radiation exposure (0, 0.2 and 1 Gy, 300 MeV/n, LET 67 KeV/μ, dose rate 1 Gy/min). For neurogenesis assessment, the NGFP mice were injected with the mitotic marker BrdU at 22 h postirradiation and brains were examined for indices of hippocampal proliferation and neurogenesis, including Ki67(+), BrdU(+), BrdU(+)NeuN(+) and DCX(+) cell numbers at short- and long-term time points (24 h and 3 months postirradiation, respectively). In the short-term group, stereology revealed fewer Ki67(+), BrdU(+) and DCX(+) cells in 1-Gy-irradiated group relative to nonirradiated control mice, fewer Ki67(+) and DCX(+) cells in 0.2 Gy group relative to control group and fewer BrdU(+) and DCX(+) cells in 1 Gy group relative to 0.2 Gy group. In contrast to the clearly observed radiation-induced, dose-dependent reductions in the short-term group across all markers, only a few neurogenesis indices were changed in the long-term irradiated groups. Notably, there were fewer surviving BrdU(+) cells in the 1 Gy group relative to 0- and 0.2-Gy-irradiated mice in the long-term group. When the short- and long-term groups were analyzed by sex, exposure to radiation had a similar effect on

  18. Cellular automata

    CERN Document Server

    Codd, E F

    1968-01-01

    Cellular Automata presents the fundamental principles of homogeneous cellular systems. This book discusses the possibility of biochemical computers with self-reproducing capability.Organized into eight chapters, this book begins with an overview of some theorems dealing with conditions under which universal computation and construction can be exhibited in cellular spaces. This text then presents a design for a machine embedded in a cellular space or a machine that can compute all computable functions and construct a replica of itself in any accessible and sufficiently large region of t

  19. Cell Proliferation and Cytotoxicity Assays.

    Science.gov (United States)

    Adan, Aysun; Kiraz, Yağmur; Baran, Yusuf

    Cell viability is defined as the number of healthy cells in a sample and proliferation of cells is a vital indicator for understanding the mechanisms in action of certain genes, proteins and pathways involved cell survival or death after exposing to toxic agents. Generally, methods used to determine viability are also common for the detection of cell proliferation. Cell cytotoxicity and proliferation assays are generally used for drug screening to detect whether the test molecules have effects on cell proliferation or display direct cytotoxic effects. Regardless of the type of cell-based assay being used, it is important to know how many viable cells are remaining at the end of the experiment. There are a variety of assay methods based on various cell functions such as enzyme activity, cell membrane permeability, cell adherence, ATP production, co-enzyme production, and nucleotide uptake activity. These methods could be basically classified into different categories: (I) dye exclusion methods such as trypan blue dye exclusion assay, (II) methods based on metabolic activity, (III) ATP assay, (IV) sulforhodamine B assay, (V) protease viability marker assay, (VI) clonogenic cell survival assay, (VII) DNA synthesis cell proliferation assays and (V) raman micro-spectroscopy. In order to choose the optimal viability assay, the cell type, applied culture conditions, and the specific questions being asked should be considered in detail. This particular review aims to provide an overview of common cell proliferation and cytotoxicity assays together with their own advantages and disadvantages, their methodologies, comparisons and intended purposes.

  20. Oxidative stress induced pulmonary endothelial cell proliferation is ...

    African Journals Online (AJOL)

    Cellular hyper-proliferation, endothelial dysfunction and oxidative stress are hallmarks of the pathobiology of pulmonary hypertension. Indeed, pulmonary endothelial cells proliferation is susceptible to redox state modulation. Some studies suggest that superoxide stimulates endothelial cell proliferation while others have ...

  1. Essential roles of the nitric oxide (no)/cGMP/protein kinase G type-Iα (PKG-Iα) signaling pathway and the atrial natriuretic peptide (ANP)/cGMP/PKG-Iα autocrine loop in promoting proliferation and cell survival of OP9 bone marrow stromal cells.

    Science.gov (United States)

    Wong, Janica C; Fiscus, Ronald R

    2011-03-01

    Inappropriate signaling conditions within bone marrow stromal cells (BMSCs) can lead to loss of BMSC survival, contributing to the loss of a proper micro-environmental niche for hematopoietic stem cells (HSCs), ultimately causing bone marrow failure. In the present study, we investigated the novel role of endogenous atrial natriuretic peptide (ANP) and the nitric oxide (NO)/cGMP/protein kinase G type-Iα (PKG-Iα) signaling pathway in regulating BMSC survival and proliferation, using the OP9 BMSC cell line commonly used for facilitating the differentiation of HSCs. Using an ANP-receptor blocker, endogenously produced ANP was found to promote cell proliferation and prevent apoptosis. NO donor SNAP (S-nitroso-N-acetylpenicillamine) at low concentrations (10 and 50 µM), which would moderately stimulate PKG activity, protected these BMSCs against spontaneous apoptosis. YC-1, a soluble guanylyl cyclase (sGC) activator, decreased the levels of apoptosis, similar to the cytoprotective effects of low-level NO. ODQ (1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one), which blocks endogenous NO-induced activation of sGC and thus lowers endogenous cGMP/PKG activity, significantly elevated apoptotic levels by 2.5- and three-fold. Pre-incubation with 8-Bromo-cGMP or ANP, which bypass the ODQ block, almost completely prevented the ODQ-induced apoptosis. A highly-specific PKG inhibitor, DT-3, at 20, and 30 µM, caused 1.5- and two-fold increases in apoptosis, respectively. ODQ and DT-3 also decreased BMSCs proliferation and colony formation. Small Interfering RNA gene knockdown of PKG-Iα increased apoptosis and decreased proliferation in BMSCs. The data suggest that basal NO/cGMP/PKG-Iα activity and autocrine ANP/cGMP/PKG-Iα are necessary for preserving OP9 cell survival and promoting cell proliferation and migration. Copyright © 2010 Wiley-Liss, Inc.

  2. Calcium signaling and cell proliferation.

    Science.gov (United States)

    Pinto, Mauro Cunha Xavier; Kihara, Alexandre Hiroaki; Goulart, Vânia A M; Tonelli, Fernanda M P; Gomes, Katia N; Ulrich, Henning; Resende, Rodrigo R

    2015-11-01

    Cell proliferation is orchestrated through diverse proteins related to calcium (Ca(2+)) signaling inside the cell. Cellular Ca(2+) influx that occurs first by various mechanisms at the plasma membrane, is then followed by absorption of Ca(2+) ions by mitochondria and endoplasmic reticulum, and, finally, there is a connection of calcium stores to the nucleus. Experimental evidence indicates that the fluctuation of Ca(2+) from the endoplasmic reticulum provides a pivotal and physiological role for cell proliferation. Ca(2+) depletion in the endoplasmatic reticulum triggers Ca(2+) influx across the plasma membrane in an phenomenon called store-operated calcium entries (SOCEs). SOCE is activated through a complex interplay between a Ca(2+) sensor, denominated STIM, localized in the endoplasmic reticulum and a Ca(2+) channel at the cell membrane, denominated Orai. The interplay between STIM and Orai proteins with cell membrane receptors and their role in cell proliferation is discussed in this review. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. The Proliferation Enhancing Effects of Salidroside on Schwann Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Hui Liu

    2017-01-01

    Full Text Available Derived from Rhodiola rosea L., which is a popular plant in Eastern Europe and Asia, salidroside has pharmacological properties including antiviral, anticancer, hepatoprotective, antidiabetic, and antioxidative effects. Recent studies show that salidroside has neurotrophic and neuroprotective effects. However, the effect of salidroside on Schwann cells (SCs and the underlying mechanisms of the salidroside-induced neurotrophin secretion have seldom been studied. In this study, the effect of salidroside on the survival, proliferation, and gene expression of Schwann cells lineage (RSC96 was studied through the examinations of the cell viability, proliferation, morphology, and expression of neurotrophic factor related genes including BDNF, GDNF, and CDNF at 2, 4, and 6 days, respectively. These results showed that salidroside significantly enhanced survival and proliferation of SCs. The underlying mechanism might involve that salidroside affected SCs growth through the modulation of several neurotrophic factors including BDNF, GDNF, and CDNF. As for the concentration, 0.4 mM, 0.2 mM, and 0.1 mM of salidroside were recommended, especially 0.2 mM. This investigation indicates that salidroside is capable of enhancing SCs survival and function in vitro, which highlights the possibility that salidroside as a drug agent to promote nerve regeneration in cellular nerve scaffold through salidroside-induced neurotrophin secretion in SCs.

  4. The Proliferation Enhancing Effects of Salidroside on Schwann Cells In Vitro.

    Science.gov (United States)

    Liu, Hui; Lv, Peizhen; Wu, Huayu; Zhang, Kun; Xu, Fuben; Zheng, Li; Zhao, Jinmin

    2017-01-01

    Derived from Rhodiola rosea L., which is a popular plant in Eastern Europe and Asia, salidroside has pharmacological properties including antiviral, anticancer, hepatoprotective, antidiabetic, and antioxidative effects. Recent studies show that salidroside has neurotrophic and neuroprotective effects. However, the effect of salidroside on Schwann cells (SCs) and the underlying mechanisms of the salidroside-induced neurotrophin secretion have seldom been studied. In this study, the effect of salidroside on the survival, proliferation, and gene expression of Schwann cells lineage (RSC96) was studied through the examinations of the cell viability, proliferation, morphology, and expression of neurotrophic factor related genes including BDNF, GDNF, and CDNF at 2, 4, and 6 days, respectively. These results showed that salidroside significantly enhanced survival and proliferation of SCs. The underlying mechanism might involve that salidroside affected SCs growth through the modulation of several neurotrophic factors including BDNF, GDNF, and CDNF. As for the concentration, 0.4 mM, 0.2 mM, and 0.1 mM of salidroside were recommended, especially 0.2 mM. This investigation indicates that salidroside is capable of enhancing SCs survival and function in vitro, which highlights the possibility that salidroside as a drug agent to promote nerve regeneration in cellular nerve scaffold through salidroside-induced neurotrophin secretion in SCs.

  5. TAp73 promotes anti-senescence-anabolism not proliferation.

    Science.gov (United States)

    Agostini, Massimiliano; Niklison-Chirou, Maria Victoria; Catani, Maria Valeria; Knight, Richard A; Melino, Gerry; Rufini, Alessandro

    2014-11-01

    TAp73, a member of the p53 family, has been traditionally considered a tumor suppressor gene, but a recent report has claimed that it can promote cellular proliferation. This assumption is based on biochemical evidence of activation of anabolic metabolism, with enhanced pentose phosphate shunt (PPP) and nucleotide biosynthesis. Here, while we confirm that TAp73 expression enhances anabolism, we also substantiate its role in inhibiting proliferation and promoting cell death. Hence, we would like to propose an alternative interpretation of the accumulating data linking p73 to cellular metabolism: we suggest that TAp73 promotes anabolism to counteract cellular senescence rather than to support proliferation.

  6. Cellular proliferation rate and insulin-like growth factor binding protein (IGFBP)-2 and IGFBP-3 and estradiol receptor alpha expression in the mammary gland of dairy heifers naturally infected with gastrointestinal nematodes during development.

    Science.gov (United States)

    Perri, A F; Dallard, B E; Baravalle, C; Licoff, N; Formía, N; Ortega, H H; Becú-Villalobos, D; Mejia, M E; Lacau-Mengido, I M

    2014-01-01

    Mammary ductal morphogenesis during prepuberty occurs mainly in response to insulin-like growth factor-1 (IGF-1) and estradiol stimulation. Dairy heifers infected with gastrointestinal nematodes have reduced IGF-1 levels, accompanied by reduced growth rate, delayed puberty onset, and lower parenchyma-stroma relationship in their mammary glands. Immunohistochemical studies were undertaken to determine variations in cell division rate, IGF-1 system components, and estradiol receptors (ESR) during peripubertal development in the mammary glands of antiparasitic-treated and untreated Holstein heifers naturally infected with gastrointestinal nematodes. Mammary biopsies were taken at 20, 30, 40, and 70 wk of age. Proliferating cell nuclear antigen immunolabeling, evident in nuclei, tended to be higher in the parenchyma of the glands from treated heifers than in those from untreated. Insulin-like growth factor binding proteins (IGFBP) type 2 and type 3 immunolabeling was cytoplasmic and was evident in stroma and parenchyma. The IGFBP2-labeled area was lower in treated than in untreated heifers. In the treated group, a maximal expression of this protein was seen at 40 wk of age, whereas in the untreated group the labeling remained constant. No differences were observed for IGFBP3 between treatment groups or during development. Immunolabeling for α ESR (ESR1) was evident in parenchymal nuclei and was higher in treated than in untreated heifers. In the treated group, ESR1 peaked at 30 wk of age and then decreased. These results demonstrate that the parasite burden in young heifers negatively influence mammary gland development, affecting cell division rate and parameters related to estradiol and IGF-1 signaling in the gland. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2016-01-01

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

  8. [Senescence and cellular immortality].

    Science.gov (United States)

    Trentesaux, C; Riou, J-F

    2010-11-01

    Senescence was originally described from the observation of the limited ability of normal cells to grow in culture, and may be generated by telomere erosion, accumulation of DNA damages, oxidative stress and modulation of oncogenes or tumor suppressor genes. Senescence corresponds to a cellular response aiming to control tumor progression by limiting cell proliferation and thus constitutes an anticancer barrier. Senescence is observed in pre-malignant tumor stages and disappears from malignant tumors. Agents used in standard chemotherapy also have the potential to induce senescence, which may partly explain their therapeutic activities. It is possible to restore senescence in tumors using targeted therapies that triggers telomere dysfunction or reactivates suppressor genes functions, which are essential for the onset of senescence.

  9. Incidental Epstein-Barr virus associated atypical lymphoid proliferation arising in a left atrial myxoma: a case of long survival without any postsurgical treatment and review of the literature.

    Science.gov (United States)

    Bartoloni, Giovanni; Pucci, Angela; Giorlandino, Alexandra; Berretta, Massimiliano; Mignosa, Carmelo; Italia, Fabrizio; Carbone, Antonino; Canzonieri, Vincenzo

    2013-01-01

    We report a case of left atrial cardiac myxoma harbouring an incidental atypical B-cell lymphoid proliferation. Histology disclosed classic myxoma cells embedded in a mucopolysaccharide-rich matrix and a micronodular atypical lymphoid proliferation under the surface of the mass. Myxoma cells were immunoreactive for calretinin, while lymphoid cells expressed B lineage markers (CD 20+, CD79a), without evidence of clonality. Moreover, they were LMP1 positive; EBNA2 negative; KSHV/HHV8 negative; and, by in situ hybridization, EBER/Epstein-Barr virus (EBV) positive and Kappa and Lambda negative. According to the 2008 WHO schemes, the present case shares close similarities either with diffuse large B-cell lymphomas growing in the context of long-standing chronic inflammation or with primary effusion lymphomas, solid variant, both associated with EBV infection. This is the sixth case of incidental atypical lymphoid proliferation discovered in a cardiac myxoma reported so far. The optimal treatment of such lesions remains undefined, but their clinical course is indolent. After an accurate staging workup, without any postsurgical treatment, the patient we observed has been well with no recurrence of the disease at 6 years of follow-up. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Suspension Matrices for Improved Schwann-Cell Survival after Implantation into the Injured Rat Spinal Cord

    Science.gov (United States)

    Patel, Vivek; Joseph, Gravil; Patel, Amit; Patel, Samik; Bustin, Devin; Mawson, David; Tuesta, Luis M.; Puentes, Rocio; Ghosh, Mousumi

    2010-01-01

    Abstract Trauma to the spinal cord produces endogenously irreversible tissue and functional loss, requiring the application of therapeutic approaches to achieve meaningful restoration. Cellular strategies, in particular Schwann-cell implantation, have shown promise in overcoming many of the obstacles facing successful repair of the injured spinal cord. Here, we show that the implantation of Schwann cells as cell suspensions with in-situ gelling laminin:collagen matrices after spinal-cord contusion significantly enhances long-term cell survival but not proliferation, as well as improves graft vascularization and the degree of axonal in-growth over the standard implantation vehicle, minimal media. The use of a matrix to suspend cells prior to implantation should be an important consideration for achieving improved survival and effectiveness of cellular therapies for future clinical application. PMID:20144012

  11. Cellular mechanotransduction

    Directory of Open Access Journals (Sweden)

    Wolfgang H. Goldmann

    2016-01-01

    Full Text Available Cell adhesion and cell–cell contacts are pre-requisites for proper metabolism, protein synthesis, cell survival, and cancer metastasis. Major transmembrane receptors are the integrins, which are responsible for cell matrix adhesions, and the cadherins, which are important for cell-cell adhesions.  Adherent cells are anchored via focal adhesions (FAs to the extracellular matrix, while cell-cell contacts are connected via focal adherens junctions (FAJs. Force transmission over considerable distances and stress focusing at these adhesion sites make them prime candidates for mechanosensors. Exactly which protein(s within FAs and FAJs or which membrane component of ion channels sense, transmit, and respond to mechano-chemical signaling is currently strongly debated and numerous candidates have been proposed.

  12. SIRT1 inhibits the mouse intestinal motility and epithelial proliferation

    Science.gov (United States)

    SIRT1 inhibits the mouse intestinal motility and epithelial proliferation. Sirtuin 1 (SIRT1), a NAD+-dependent histone deacetylase, is involved in a wide array of cellular processes, including glucose homeostasis, energy metabolism, proliferation and apoptosis, and immune response. However, it is un...

  13. Apigenin inhibits proliferation and migratory properties of Barrett's ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of apigenin on Barrett's esophagus–associated esophageal adenocarcinoma (BEAC) cells OE33, and also to ascertain the mechanism by which it inhibits cellular proliferation and motility. Methods: Proliferation index of OE33 in the absence and presence of apigenin was determined by.

  14. The impact of NudCD1 on renal carcinoma cell proliferation, migration, and invasion.

    Science.gov (United States)

    Wang, R-J; Wang, N; Cui, G; Chen, Y; Zhong, H; Tang, J

    2018-02-01

    Renal cell carcinoma (RCC) is the most common malignant tumor in the urogenital system. Its easily metastatic characteristics greatly reduce the postoperative survival rate. NudCD1, as a proto-oncogene, may be involved in the proliferation, migration, and invasion of renal cell carcinoma cell. This study intends to explore the expression of NudCD1 in renal cancer tissue and its effect on renal cell behavior. NudCD1 expression in RCC tissue was tested Western blot. The cellular localization of NudCD1 was detected by immunohistochemistry (IHC). NudCD1 highly expressed RCC cell line was selected. NudCD1 knockdown or overexpression was performed through cell transfection. Cell proliferation, migration, and invasion were assessed by MTT assay, wound scratch assay, and transwell assay, respectively. NudCD1 mainly located in the cytoplasm and significantly upregulated in RCC tissue compared with adjacent normal control (p < 0.05). NudCD1 expressed highest in A498 cell line among several RCC cell lines. NudCD1 expression was positively correlated with cell proliferation, migration, and invasion in A498. NudCD1 may be treated as a key factor in regulating cell behavior. NudCD1 significantly increased in RCC and was positively correlated with cell proliferation, migration, and invasion. It could be used as an indicator for the early screening and potential treatment target for RCC.

  15. Chronic toluene exposure induces cell proliferation in the mice SVZ but not migration through the RMS.

    Science.gov (United States)

    Franco, Ireri; Valdez-Tapia, Mariana; Sanchez-Serrano, Sinthia L; Cruz, Silvia L; Lamas, Monica

    2014-07-11

    Abuse of toluene-containing inhalants is associated to various cognitive impairments that have been partly associated to deviation of the hippocampal neurogenesis processes during adulthood. In the present study we analyzed the effect of chronic toluene exposure (6000ppm) on cell proliferation and migration in the other selected area of the rodent brain where neurogenesis persist throughout adulthood, the subventricular zone of the lateral ventricle (SVZ). We used an anti-Ki67 antibody to evaluate SVZ cell proliferation, BrdU to evaluate cell survival and double-staining with BrdU and the migration marker doublecortin (DCX) to evaluate migration, by immunofluorescence 2h, 1, 5, 10 or 15 days after 20 sessions of toluene exposure. We found that toluene induced an initial burst of cell proliferation in the SVZ but not a significant increase in migration toward the rostral migratory stream (RMS) or the number of cells that migrate to the olfactory bulb. In addition, we detected a small number of new migrating cells in the corpus callosum and striatum of control mice that was similar in toluene-exposed brains. These results may underline the homeostatic capabilities of the populations of dividing cells, previously demonstrated using other drugs of abuse and demonstrate that toluene misuse can alter cellular proliferation in the postnatal brain. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Knockdown of Cripto-1 inhibits the proliferation, migration, invasion ...

    Indian Academy of Sciences (India)

    We performed Cell Counting Kit-8, 5-ethynyl-2-deoxyuridine (EdU) incorporation assay and flowcytometry to detect the cellular proliferation and cycle. The transwell assay was used to observe cellular migration andinvasion. The ability of angiogenesis was evaluated by tube formation assay. Our results showed that CR-1 ...

  17. PI(3,4,5)P3 Engagement Restricts Akt Activity to Cellular Membranes.

    Science.gov (United States)

    Ebner, Michael; Lučić, Iva; Leonard, Thomas A; Yudushkin, Ivan

    2017-02-02

    Protein kinase B/Akt regulates cellular metabolism, survival, and proliferation in response to hormones and growth factors. Hyperactivation of Akt is frequently observed in cancer, while Akt inactivation is associated with severe diabetes. Here, we investigated the molecular and cellular mechanisms that maintain Akt activity proportional to the activating stimulus. We show that binding of phosphatidylinositol-3,4,5-trisphosphate (PIP3) or PI(3,4)P2 to the PH domain allosterically activates Akt by promoting high-affinity substrate binding. Conversely, dissociation from PIP3 was rate limiting for Akt dephosphorylation, dependent on the presence of the PH domain. In cells, active Akt associated primarily with cellular membranes. In contrast, a transforming mutation that uncouples kinase activation from PIP3 resulted in the accumulation of hyperphosphorylated, active Akt in the cytosol. Our results suggest that intramolecular allosteric and cellular mechanisms cooperate to restrict Akt activity to cellular membranes, thereby enhancing the fidelity of Akt signaling and the specificity of downstream substrate phosphorylation. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. XIAP antagonist embelin inhibited proliferation of cholangiocarcinoma cells.

    Directory of Open Access Journals (Sweden)

    Cody J Wehrkamp

    Full Text Available Cholangiocarcinoma cells are dependent on antiapoptotic signaling for survival and resistance to death stimuli. Recent mechanistic studies have revealed that increased cellular expression of the E3 ubiquitin-protein ligase X-linked inhibitor of apoptosis (XIAP impairs TRAIL- and chemotherapy-induced cytotoxicity, promoting survival of cholangiocarcinoma cells. This study was undertaken to determine if pharmacologic antagonism of XIAP protein was sufficient to sensitize cholangiocarcinoma cells to cell death. We employed malignant cholangiocarcinoma cell lines and used embelin to antagonize XIAP protein. Embelin treatment resulted in decreased XIAP protein levels by 8 hours of treatment with maximal effect at 16 hours in KMCH and Mz-ChA-1 cells. Assessment of nuclear morphology demonstrated a concentration-dependent increase in nuclear staining. Interestingly, embelin induced nuclear morphology changes as a single agent, independent of the addition of TNF-related apoptosis inducing ligand (TRAIL. However, caspase activity assays revealed that increasing embelin concentrations resulted in slight inhibition of caspase activity, not activation. In addition, the use of a pan-caspase inhibitor did not prevent nuclear morphology changes. Finally, embelin treatment of cholangiocarcinoma cells did not induce DNA fragmentation or PARP cleavage. Apoptosis does not appear to contribute to the effects of embelin on cholangiocarcinoma cells. Instead, embelin caused inhibition of cell proliferation and cell cycle analysis indicated that embelin increased the number of cells in S and G2/M phase. Our results demonstrate that embelin decreased proliferation in cholangiocarcinoma cell lines. Embelin treatment resulted in decreased XIAP protein expression, but did not induce or enhance apoptosis. Thus, in cholangiocarcinoma cells the mechanism of action of embelin may not be dependent on apoptosis.

  19. Overexpression of the human DEK oncogene reprograms cellular metabolism and promotes glycolysis.

    Directory of Open Access Journals (Sweden)

    Marie C Matrka

    Full Text Available The DEK oncogene is overexpressed in many human malignancies including at early tumor stages. Our reported in vitro and in vivo models of squamous cell carcinoma have demonstrated that DEK contributes functionally to cellular and tumor survival and to proliferation. However, the underlying molecular mechanisms remain poorly understood. Based on recent RNA sequencing experiments, DEK expression was necessary for the transcription of several metabolic enzymes involved in anabolic pathways. This identified a possible mechanism whereby DEK may drive cellular metabolism to enable cell proliferation. Functional metabolic Seahorse analysis demonstrated increased baseline and maximum extracellular acidification rates, a readout of glycolysis, in DEK-overexpressing keratinocytes and squamous cell carcinoma cells. DEK overexpression also increased the maximum rate of oxygen consumption and therefore increased the potential for oxidative phosphorylation (OxPhos. To detect small metabolites that participate in glycolysis and the tricarboxylic acid cycle (TCA that supplies substrate for OxPhos, we carried out NMR-based metabolomics studies. We found that high levels of DEK significantly reprogrammed cellular metabolism and altered the abundances of amino acids, TCA cycle intermediates and the glycolytic end products lactate, alanine and NAD+. Taken together, these data support a scenario whereby overexpression of the human DEK oncogene reprograms keratinocyte metabolism to fulfill energy and macromolecule demands required to enable and sustain cancer cell growth.

  20. Overexpression of the human DEK oncogene reprograms cellular metabolism and promotes glycolysis

    Science.gov (United States)

    Watanabe, Miki; Muraleedharan, Ranjithmenon; Lambert, Paul F.; Lane, Andrew N.; Romick-Rosendale, Lindsey E.; Wells, Susanne I.

    2017-01-01

    The DEK oncogene is overexpressed in many human malignancies including at early tumor stages. Our reported in vitro and in vivo models of squamous cell carcinoma have demonstrated that DEK contributes functionally to cellular and tumor survival and to proliferation. However, the underlying molecular mechanisms remain poorly understood. Based on recent RNA sequencing experiments, DEK expression was necessary for the transcription of several metabolic enzymes involved in anabolic pathways. This identified a possible mechanism whereby DEK may drive cellular metabolism to enable cell proliferation. Functional metabolic Seahorse analysis demonstrated increased baseline and maximum extracellular acidification rates, a readout of glycolysis, in DEK-overexpressing keratinocytes and squamous cell carcinoma cells. DEK overexpression also increased the maximum rate of oxygen consumption and therefore increased the potential for oxidative phosphorylation (OxPhos). To detect small metabolites that participate in glycolysis and the tricarboxylic acid cycle (TCA) that supplies substrate for OxPhos, we carried out NMR-based metabolomics studies. We found that high levels of DEK significantly reprogrammed cellular metabolism and altered the abundances of amino acids, TCA cycle intermediates and the glycolytic end products lactate, alanine and NAD+. Taken together, these data support a scenario whereby overexpression of the human DEK oncogene reprograms keratinocyte metabolism to fulfill energy and macromolecule demands required to enable and sustain cancer cell growth. PMID:28558019

  1. Determining lineage pathways from cellular barcoding experiments

    NARCIS (Netherlands)

    Perié, Leïla; Hodgkin, Philip D; Naik, Shalin H; Schumacher, Ton N; de Boer, Rob J; Duffy, Ken R

    2014-01-01

    Cellular barcoding and other single-cell lineage-tracing strategies form experimental methodologies for analysis of in vivo cell fate that have been instrumental in several significant recent discoveries. Due to the highly nonlinear nature of proliferation and differentiation, interrogation of the

  2. Cellular proliferation and regeneration following tissue damage. Progress report. [Eyes

    Energy Technology Data Exchange (ETDEWEB)

    Harding, C.V.

    1976-10-01

    Results are reported from a study of wound healing in tissues of the eye, particularly lens, cornea, and surrounding tissues. The reactions of these tissues to mechanical injuries, as well as injuries induced by chemotoxic agents were studied. It is postulated that a better understanding of the basic reactions of the eye to injurious agents may be of importance in the evaluation of potential environmental hazards.

  3. Fatty acids and breast cancer cell proliferation.

    Science.gov (United States)

    Hardy, R W; Wickramasinghe, N S; Ke, S C; Wells, A

    1997-01-01

    We and others have shown that fatty acids are important regulators of breast cancer cell proliferation. In particular individual fatty acids specifically alter EGF-induced cell proliferation in very different ways. This regulation is mediated by an EGFR/G-protein signaling pathway. Understanding the molecular mechanisms of how this signaling pathway functions and how fatty acids regulate it will provide important information on the cellular and molecular basis for the association of dietary fat and cancer. Furthermore these in vitro studies may explain data previously obtained from in vivo animal studies and identify "good" as well as "bad" fatty acids with respect to the development of cancer.

  4. Chemosensitizing effects of carbon-based nanomaterials in cancer cells: enhanced apoptosis and inhibition of proliferation as underlying mechanisms.

    Science.gov (United States)

    Erdmann, Kati; Ringel, Jessica; Hampel, Silke; Rieger, Christiane; Huebner, Doreen; Wirth, Manfred P; Fuessel, Susanne

    2014-10-10

    Recent studies have shown that carbon nanomaterials such as carbon nanofibres (CNFs) and multi-walled carbon nanotubes (CNTs) can exert antitumor activities themselves and sensitize cancer cells to conventional chemotherapeutics such as carboplatin and cisplatin. In the present study, the chemosensitizing effect of CNFs and CNTs on cancer cells of urological origin was investigated regarding the underlying mechanisms. Prostate cancer (DU-145, PC-3) and bladder cancer (EJ28) cells were treated with carbon nanomaterials (CNFs, CNTs) and chemotherapeutics (carboplatin, cisplatin) alone as well as in combination for 24 h. Forty-eight(EJ28) or 72 h (DU-145, PC-3) after the end of treatment the effects on cellular proliferation,clonogenic survival, cell death rate and cell cycle distribution were evaluated. Depending on the cell line, simultaneous administration of chemotherapeutics and carbon nanomaterials produced an additional inhibition of cellular proliferation and clonogenic survival of up to 77% and 98%, respectively, compared to the inhibitory effects of the chemotherapeutics alone. These strongly enhanced antiproliferative effects were accompanied by an elevated cell death rate, which was predominantly mediated via apoptosis and not by necrosis. The antitumor effects of combinations with CNTs were less pronounced than those with CNFs. The enhanced effects of the combinatory treatments on cellular function were mostly of additive to partly synergistic nature. Furthermore, cell cycle analysis demonstrated an arrest at the G2/M phase mediated by a monotreatment with chemotherapeutics. Following combinatory treatments, mostly less than or nearly additive increases of cell fractions in the G2/M phase could be observed. In conclusion,the pronounced chemosensitizing effects of CNFs and CNTs were mediated by an enhanced apoptosis and inhibition of proliferation. The combination of carbon-based nanomaterials and conventional chemotherapeutics represents a novel approach

  5. Surviving the crash: T-cell homeostasis

    Indian Academy of Sciences (India)

    TOSHIBA

    Spatial and temporal elements. – Cellular sites for the integration of cell death and survival cues. – Spatial regulation of Notch activity for cell survival. Page 4. Cell survival is determined by the availability and uptake of nutrients live dead. Activated T-cells. T-cells. Page 5. dead wildtype. Bax active -6A7. Nucleus – H33342.

  6. Cellular Homeostasis and Antioxidant Response in Epithelial HT29 Cells on Titania Nanotube Arrays Surface

    Directory of Open Access Journals (Sweden)

    Rabiatul Basria SMN Mydin

    2017-01-01

    Full Text Available Cell growth and proliferative activities on titania nanotube arrays (TNA have raised alerts on genotoxicity risk. Present toxicogenomic approach focused on epithelial HT29 cells with TNA surface. Fledgling cell-TNA interaction has triggered G0/G1 cell cycle arrests and initiates DNA damage surveillance checkpoint, which possibly indicated the cellular stress stimuli. A profound gene regulation was observed to be involved in cellular growth and survival signals such as p53 and AKT expressions. Interestingly, the activation of redox regulator pathways (antioxidant defense was observed through the cascade interactions of GADD45, MYC, CHECK1, and ATR genes. These mechanisms furnish to protect DNA during cellular division from an oxidative challenge, set in motion with XRRC5 and RAD50 genes for DNA damage and repair activities. The cell fate decision on TNA-nanoenvironment has been reported to possibly regulate proliferative activities via expression of p27 and BCL2 tumor suppressor proteins, cogent with SKP2 and BCL2 oncogenic proteins suppression. Findings suggested that epithelial HT29 cells on the surface of TNA may have a positive regulation via cell-homeostasis mechanisms: a careful circadian orchestration between cell proliferation, survival, and death. This nanomolecular knowledge could be beneficial for advanced medical applications such as in nanomedicine and nanotherapeutics.

  7. Anatomically discrete sex differences and enhancement by testosterone of cell proliferation in the telencephalic ventricle zone of the adult canary brain.

    Science.gov (United States)

    Barker, Jennifer M; Ball, Gregory F; Balthazart, Jacques

    2014-01-01

    Previous work in songbirds has suggested that testosterone increases neuronal recruitment and survival in HVC but does not affect neuronal proliferation in the ventricular zone and that males and females have similar rates of proliferation except at discrete locations. Many of these conclusions are however based on limited data or were inferred indirectly. Here we specifically tested the effects of testosterone on cellular proliferation in the ventricular zone of both male and female adult canaries. We implanted adult birds of both sexes with testosterone or empty implants for 1 week and injected them with BrdU. One day later, we collected their brains and quantified BrdU-positive cells in the ventricular zone (VZ) at different rostro-caudal levels of the brain, ranging from the level where the song nucleus Area X occurs through the caudal extent of HVC. Proliferation in the dorsal part of the VZ was low and unaffected by sex or testosterone treatment. In the ventral part of the VZ, females had more proliferating cells than males, but only at rostral levels, near Area X. Also in the ventral part of the VZ, testosterone increased proliferation in birds of both sexes, but only in the mid- to caudal-VZ, caudal to the level of Area X, around the septum and HVC. We thus demonstrate here that there is both an effect of testosterone and possibly a more subtle effect of sex on cellular proliferation in the adult songbird brain, and that these effects are specific to different levels of the brain. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Cracking the survival code

    Science.gov (United States)

    Füllgrabe, Jens; Heldring, Nina; Hermanson, Ola; Joseph, Bertrand

    2014-01-01

    Modifications of histones, the chief protein components of the chromatin, have emerged as critical regulators of life and death. While the “apoptotic histone code” came to light a few years ago, accumulating evidence indicates that autophagy, a cell survival pathway, is also heavily regulated by histone-modifying proteins. In this review we describe the emerging “autophagic histone code” and the role of histone modifications in the cellular life vs. death decision. PMID:24429873

  9. Contribution of constitutively proliferating precursor cell subtypes to dentate neurogenesis after cortical infarcts

    Directory of Open Access Journals (Sweden)

    Oberland Julia

    2010-11-01

    Full Text Available Abstract Background It is well known that focal ischemia increases neurogenesis in the adult dentate gyrus of the hippocampal formation but the cellular mechanisms underlying this proliferative response are only poorly understood. We here investigated whether precursor cells which constitutively proliferate before the ischemic infarct contribute to post-ischemic neurogenesis. To this purpose, transgenic mice expressing green fluorescent protein (GFP under the control of the nestin promoter received repetitive injections of the proliferation marker bromodeoxyuridine (BrdU prior to induction of cortical infarcts. We then immunocytochemically analyzed the fate of these BrdU-positive precursor cell subtypes from day 4 to day 28 after the lesion. Results Quantification of BrdU-expressing precursor cell populations revealed no alteration in number of radial glia-like type 1 cells but a sequential increase of later precursor cell subtypes in lesioned animals (type 2a cells at day 7, type 3 cells/immature neurons at day 14. These alterations result in an enhanced survival of mature neurons 4 weeks postinfarct. Conclusions Focal cortical infarcts recruit dentate precursor cells generated already before the infarct and significantly contribute to an enhanced neurogenesis. Our findings thereby increase our understanding of the complex cellular mechanisms of postlesional neurogenesis.

  10. bFGF and Activin A function to promote survival and proliferation of single iPS cells in conditioned half-exchange mTeSR1 medium.

    Science.gov (United States)

    Guo, Xiaoling; Lian, Ruiling; Guo, Yonglong; Liu, Qing; Ji, Qingshan; Chen, Jiansu

    2015-07-01

    Human induced pluripotent stem (iPS) cells can be well maintained by clonal growth. The pluripotent growth of single iPS cells is limited by low survival. To facilitate robust single iPS cells cultured in vitro, half-exchange mTeSR1 medium (HM), whole-exchange medium (WM) and iPS cell-derived conditioned medium (iPS-CM) culture were used. The effects of bFGF and Activin A on the growth of single iPS cells were explored. The dissociation and propagation of single iPS cells also included Accutase enzymatic isolation, Rho-associated protein kinase (ROCK) inhibitor Y27632 protection and high-density single-cell seeding (1 × 10(6) cells/well). CCK-8 assays demonstrated that the viability of clonal iPS cells in mTeSR1 medium and single iPS cells in HM, iPS-CM or WM supplemented with 100 ng/ml bFGF and 10 ng/ml Activin A was significantly higher than that in WM. Annexin v and propidium iodide (PI) assay, Calcein AM and EthD-III double staining also confirmed the similar results. ELISA assays showed that the levels of bFGF and Activin A of single iPS cells in HM and iPS-CM were higher than single iPS cells in WM. Meanwhile, Reverse Transcription-Polymerase Chain Reaction (RT-PCR), quantitative Polymerase Chain Reaction (qPCR), Western Blotting (WB), Immunofluorescence (IF) and karyotype analysis revealed that HM culture was able to maintain undifferentiated markers of Nanog, Klf4, Sox2, Oct4, and did not affect the karyotype of iPS cells. Undifferentiated single iPS cells in HM displayed homogenized growth. These findings demonstrate that bFGF and Activin A are important for the survival and growth of single iPS cells. HM culture system combined Accutase, Y27632 and high-density single-cell seeding can facilitate short-term growth of single iPS cells in vitro.

  11. Amino acids and autophagy: cross-talk and co-operation to control cellular homeostasis.

    Science.gov (United States)

    Carroll, Bernadette; Korolchuk, Viktor I; Sarkar, Sovan

    2015-10-01

    Maintenance of amino acid homeostasis is important for healthy cellular function, metabolism and growth. Intracellular amino acid concentrations are dynamic; the high demand for protein synthesis must be met with constant dietary intake, followed by cellular influx, utilization and recycling of nutrients. Autophagy is a catabolic process via which superfluous or damaged proteins and organelles are delivered to the lysosome and degraded to release free amino acids into the cytoplasm. Furthermore, autophagy is specifically activated in response to amino acid starvation via two key signaling cascades: the mammalian target of rapamycin (mTOR) complex 1 (mTORC1) and the general control nonderepressible 2 (GCN2) pathways. These pathways are key regulators of the integration between anabolic (amino acid depleting) and catabolic (such as autophagy which is amino acid replenishing) processes to ensure intracellular amino acid homeostasis. Here, we discuss the key roles that amino acids, along with energy (ATP, glucose) and oxygen, are playing in cellular growth and proliferation. We further explore how sophisticated methods are employed by cells to sense intracellular amino acid concentrations, how amino acids can act as a switch to dictate the temporal and spatial activation of anabolic and catabolic processes and how autophagy contributes to the replenishment of free amino acids, all to ensure cell survival. Relevance of these molecular processes to cellular and organismal physiology and pathology is also discussed.

  12. GM-CSF produced by nonhematopoietic cells is required for early epithelial cell proliferation and repair of injured colonic mucosa.

    Science.gov (United States)

    Egea, Laia; McAllister, Christopher S; Lakhdari, Omar; Minev, Ivelina; Shenouda, Steve; Kagnoff, Martin F

    2013-02-15

    GM-CSF is a growth factor that promotes the survival and activation of macrophages and granulocytes, as well as dendritic cell differentiation and survival in vitro. The mechanism by which exogenous GM-CSF ameliorates the severity of Crohn's disease in humans and colitis in murine models has mainly been considered to reflect its activity on myeloid cells. We used GM-CSF-deficient (GM-CSF(-/-)) mice to probe the functional role of endogenous host-produced GM-CSF in a colitis model induced after injury to the colon epithelium. Dextran sodium sulfate (DSS), at doses that resulted in little epithelial damage and mucosal ulceration in wild type mice, caused marked colon ulceration and delayed ulcer healing in GM-CSF(-/-) mice. Colon crypt epithelial cell proliferation in vivo was significantly decreased in GM-CSF(-/-) mice at early times after DSS injury. This was paralleled by decreased expression of crypt epithelial cell genes involved in cell cycle, proliferation, and wound healing. Decreased crypt cell proliferation and delayed ulcer healing in GM-CSF(-/-) mice were rescued by exogenous GM-CSF, indicating the lack of a developmental abnormality in the epithelial cell proliferative response in those mice. Nonhematopoietic cells, and not myeloid cells, produced the GM-CSF important for colon epithelial proliferation after DSS-induced injury, as revealed by bone marrow chimera and dendritic cell-depletion experiments, with colon epithelial cells being the cellular source of GM-CSF. Endogenous epithelial cell-produced GM-CSF has a novel nonredundant role in facilitating epithelial cell proliferation and ulcer healing in response to injury of the colon crypt epithelium.

  13. The Chemical Biology of Nitric Oxide. Implications in Cellular Signaling

    Science.gov (United States)

    Thomas, Douglas D.; Ridnour, Lisa A.; Isenberg, Jeffrey S.; Flores-Santana, Wilmarie; Switzer, Christopher H.; Donzellie, Sonia; Hussain, Perwez; Vecoli, Cecilia; Paolocci, Nazareno; Ambs, Stefan; Colton, Carol; Harris, Curtis; Roberts, David D.; Wink, David A.

    2008-01-01

    Nitric oxide (NO) has earned the reputation of being a signaling mediator with many diverse and often opposing biological activities. The diversity in response to this simple diatomic molecule comes from the enormous variety of chemical reactions and biological properties associated with it. In the last few years, the importance of steady state NO concentrations have emerged as a key determinant of its biological function. Precise cellular responses are differentially regulated by specific NO concentration. We propose 5 basic distinct concentration levels of NO activity; cGMP mediated processes ([NO] 400 nM) and nitrosative stress (1 µM). In general, lower NO concentrations promote cell survival and proliferation, while higher levels favor cell cycle arrest, apoptosis, and senescence. Free radical interactions will also influence NO signaling. One of the consequences of reactive oxygen species (ROS) generation is to reduce NO concentrations. This antagonizes the signaling of nitric oxide and in some cases results in converting a cell cycle arrest profile to a cell survival one. The resulting reactive nitrogen species (RNS) that are generated from these reactions can also have biological effects and increase oxidative and nitrosative stress responses. A number of factors determine the formation of NO and its concentration, such as diffusion, consumption, and substrate availability which are referred to as Kinetic Determinants for Molecular Target Interactions. These are the chemical and biochemical parameters that shape cellular responses to NO. Herein we discuss signal transduction and the chemical biology of NO in terms of the direct and indirect reactions. PMID:18439435

  14. Multifaceted role of prohibitin in cell survival and apoptosis.

    Science.gov (United States)

    Peng, Ya-Ting; Chen, Ping; Ouyang, Ruo-Yun; Song, Lei

    2015-09-01

    Human eukaryotic prohibitin (prohibitin-1 and prohibitin-2) is a membrane protein with different cellular localizations. It is involved in multiple cellular functions, including energy metabolism, proliferation, apoptosis, and senescence. The subcellular localization of prohibitin may determine its functions. Membrane prohibitin regulate the cellular signaling of membrane transport, nuclear prohibitin control transcription activation and the cell cycle, and mitochondrial prohibitin complex stabilize the mitochondrial genome and modulate mitochondrial dynamics, mitochondrial morphology, mitochondrial biogenesis, and the mitochondrial intrinsic apoptotic pathway. Moreover, prohibitin can translocates into the nucleus or the mitochondria under apoptotic signals and the subcellular shuttling of prohibitin is necessary for apoptosis process. Apoptosis is the process of programmed cell death that is important for the maintenance of normal physiological functions. Consequently, any alteration in the content, post-transcriptional modification (i.e. phosphorylation) or the nuclear or mitochondrial translocation of prohibitin may influence cell fate. Understanding the mechanisms of the expression and regulation of prohibitin may be useful for future research. This review provides an overview of the multifaceted and essential roles played by prohibitin in the regulation of cell survival and apoptosis.

  15. Proliferation Security Initiative (PSI)

    National Research Council Canada - National Science Library

    Squassoni, Sharon

    2005-01-01

    President Bush announced the Proliferation Security Initiative (PSI) on May 31, 2003. Since then, 16 nations have pledged their cooperation in interdicting shipments of weapons of mass destruction-related...

  16. TAp73 promotes anti-senescence-anabolism not proliferation

    OpenAIRE

    Agostini, Massimiliano; Niklison-Chirou, Maria Victoria; Catani, Maria Valeria; Knight, Richard A.; Melino, Gerry; Rufini, Alessandro

    2014-01-01

    TAp73, a member of the p53 family, has been traditionally considered a tumor suppressor gene, but a recent report has claimed that it can promote cellular proliferation. This assumption is based on biochemical evidence of activation of anabolic metabolism, with enhanced pentose phosphate shunt (PPP) and nucleotide biosynthesis. Here, while we confirm that TAp73 expression enhances anabolism, we also substantiate its role in inhibiting proliferation and promoting cell death. Hence, we would li...

  17. Análise comparativa da proliferação celular entre carcinomas de células escamosas orais HPV-positivos e HPV-negativos Comparative analysis of the cellular proliferation between HPV-positive and HPV-negative oral squamous cell carcinomas

    Directory of Open Access Journals (Sweden)

    Danielle Albuquerque Pires Rocha

    2007-08-01

    , previously analyzed regarding the presence or absence of HPV, as well as the viral type, using PCR (primers GP5+/GP6+ and dot blot hybridization, respectively. Immunohistochemical study was performed by streptoavidin-biotin technique with antibody against nuclear protein Ki-67. RESULTS: The mean of positivity index of the HPV-positive OSCC (17.7% was greater than HPV-negative OSCC (14.2%, however the statistic analysis showed that standard deviation in both groups was very high, almost equal the mean (14% and 9.5%, respectively. The Mann-Whitney non-parametric statistic test disclosed that there wasn't a significantly statistical difference between the groups. DISCUSSION: Similar studies to these are few and they are not concordant in demonstrating a bigger tumoral proliferative activity in those cases infected by HPV in relation to those not infected, either through the analysis of the protein expression related to the cellular cycle as in the direct analysis of the tumoral proliferative fraction. CONCLUSION: There were not differences in the rates of cell proliferation between the HPV-positive and HPV-negative grups.

  18. Cellular IRES-mediated translation

    Science.gov (United States)

    2011-01-01

    Translation of cellular mRNAs via initiation at internal ribosome entry sites (IRESs) has received increased attention during recent years due to its emerging significance for many physiological and pathological stress conditions in eukaryotic cells. Expression of genes bearing IRES elements in their mRNAs is controlled by multiple molecular mechanisms, with IRES-mediated translation favored under conditions when cap-dependent translation is compromised. In this review, we discuss recent advances in the field and future directions that may bring us closer to understanding the complex mechanisms that guide cellular IRES-mediated expression. We present examples in which the competitive action of IRES-transacting factors (ITAFs) plays a pivotal role in IRES-mediated translation and thereby controls cell-fate decisions leading to either pro-survival stress adaptation or cell death. PMID:21220943

  19. Age and cellular composition influence overall survival in a collective of non-immunocompromised patients with EBV-positive diffuse large B-cell lymphoma from a German lymphoma center.

    Science.gov (United States)

    Jöhrens, Korinna; Trappe, Ralf Ulrich; Lenze, Dido; Pfreundschuh, Michael; Ziepert, Marita; Hummel, Michael; Anagnostopoulos, Ioannis

    2016-12-01

    We investigated 41 diffuse large B-cell lymphomas (DLBCL) diagnosed at one center harboring ≥50% of latently Epstein-Barr virus (EBV)-infected neoplastic cells occurring in 34 patients aged ≥50 years and in 7 patients younger than 50 years in the absence of any known immunodeficiency for the expression patterns of EBV latent and immediate-early proteins, for the differentiation stage of the neoplastic cells, the presence of cytogenetic alterations and a possible co-infection with the human herpes virus (HHV)-8. Here, we show that EBV-positive DLBCLs rarely arise from naïve and more frequently from post-germinal center B-cells that often contain crippling immunoglobulin gene mutations. Most of the lymphomas did not exhibit breaks in the BCL2, BCL6, and MYC genes and none of the cases investigated contained HHV-8 sequences. Patients aged impact on overall survival.

  20. Niclosamide, an anti-helminthic molecule, downregulates the retroviral oncoprotein Tax and pro-survival Bcl-2 proteins in HTLV-1-transformed T lymphocytes

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    Xiang, Di [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Yuan, Yunsheng [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai (China); Chen, Li [Pharmacy College, Fujian University of Traditional Chinese Medicine, Fuzhou (China); Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Liu, Xin; Belani, Chandra [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Cheng, Hua, E-mail: hcheng@ihv.umaryland.edu [Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Department Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States)

    2015-08-14

    Adult T cell leukemia and lymphoma (ATL) is a highly aggressive form of hematological malignancy and is caused by chronic infection of human T cell leukemia virus type 1 (HTLV-1). The viral genome encodes an oncogenic protein, Tax, which plays a key role in transactivating viral gene transcription and in deregulating cellular oncogenic signaling to promote survival, proliferation and transformation of virally infected T cells. Hence, Tax is a desirable therapeutic target, particularly at early stage of HTLV-1-mediated oncogenesis. We here show that niclosamide, an anti-helminthic molecule, induced apoptosis of HTLV-1-transformed T cells. Niclosamide facilitated degradation of the Tax protein in proteasome. Consistent with niclosamide-mediated Tax degradation, this compound inhibited activities of MAPK/ERK1/2 and IκB kinases. In addition, niclosamide downregulated Stat3 and pro-survival Bcl-2 family members such as Mcl-1 and repressed the viral gene transcription of HTLV-1 through induction of Tax degradation. Since Tax, Stat3 and Mcl-1 are crucial molecules for promoting survival and growth of HTLV-1-transformed T cells, our findings demonstrate a novel mechanism of niclosamide in inducing Tax degradation and downregulating various cellular pro-survival molecules, thereby promoting apoptosis of HTLV-1-associated leukemia cells. - Highlights: • Niclosamide is a promising therapeutic candidate for adult T cell leukemia. • Niclosamide employs a novel mechanism through proteasomal degradation of Tax. • Niclosamide downregulates certain cellular pro-survival molecules.

  1. Proliferation and survival signaling from both Jak2-V617F and Lyn involving GSK3 and mTOR/p70S6K/4EBP1 in PVTL-1 cell line newly established from acute myeloid leukemia transformed from polycythemia vera.

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    Toshikage Nagao

    Full Text Available The gain of function mutation JAK2-V617F is very frequently found in myeloproliferative neoplasms (MPNs and is strongly implicated in pathogenesis of these and other hematological malignancies. Here we report establishment of a new leukemia cell line, PVTL-1, homozygous for JAK2-V617F from a 73-year-old female patient with acute myeloid leukemia (AML transformed from MPN. PVTL-1 is positive for CD7, CD13, CD33, CD34, CD117, HLA-DR, and MPO, and has complex karyotypic abnormalities, 44,XX,-5q,-7,-8,add(11(p11.2,add(11(q23,-16,+21,-22,+mar1. Sequence analysis of JAK2 revealed only the mutated allele coding for Jak2-V617F. Proliferation of PVTL-1 was inhibited and apoptosis was induced by the pan-Jak inhibitor Jak inhibitor-1 (JakI-1 or dasatinib, which inhibits the Src family kinases as well as BCR/ABL. Consistently, the Src family kinase Lyn was constitutively activated with phosphorylation of Y396 in the activation loop, which was inhibited by dasatinib but not by JakI-1. Further analyses with JakI-1 and dasatinib indicated that Jak2-V617F phosphorylated STAT5 and SHP2 while Lyn phosphorylated SHP1, SHP2, Gab-2, c-Cbl, and CrkL to induce the SHP2/Gab2 and c-Cbl/CrkL complex formation. In addition, JakI-1 and dasatinib inactivated the mTOR/p70S6K/4EBP1 pathway and reduced the inhibitory phosphorylation of GSK3 in PVTL-1 cells, which correlated with their effects on proliferation and survival of these cells. Furthermore, inhibition of GSK3 by its inhibitor SB216763 mitigated apoptosis induced by dasatinib but not by JakI-1. Together, these data suggest that apoptosis may be suppressed in PVTL-1 cells through inactivation of GSK3 by Lyn as well as Jak2-V617F and additionally through activation of STAT5 by Jak2-V617F. It is also speculated that activation of the mTOR/p70S6K/4EBP1 pathway may mediate proliferation signaling from Jak2-V617F and Lyn. PVTL-1 cells may provide a valuable model system to elucidate the molecular mechanisms involved in

  2. p53/Surviving Ratio as a Parameter for Chemotherapy Induction Response in Children with Acute Myeloid Leukemia

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    Rinaldi Lenggana

    2016-11-01

    Full Text Available Acute myeloid leukemia (AML is a malignancy that is often found in children. Many studies into the failure of apoptosis function, or programmed cell death, is one of the most important regulatory mechanisms of cellular hemostasis which is closely linked to the development of cancer, are important. Also, regulation of the apoptotic (p53 and anti-apoptotic (surviving proteins influence treatment outcome. One role of p53 is to monitor cellular stress necessary to induce apoptosis. Surviving (BIRC5 is a group of proteins in the apoptosis inhibitor which works by inhibiting caspase-3. The role of surviving is considered very important in oncogenesis proliferation and cell growth regulation. Chemotherapy in childhood AML can inhibit cell growth and induce slowing as well as stopping the cell cycle. Thus, the aim of this study was to compare p53 and surviving before and after receiving induction chemotherapy in children with AML and also to determine the p53/surviving ratio. Peripheral blood mononuclear cells were collected from AML children before treatment and three months after starting their induction therapy. p53 and surviving were measured by flowcytometry using monoclonal antibodies. Data were analyzed by t-test for comparison between groups and Spearman’s test to find out the correlation between variables with a significant value of p < 0.05. A total of 8 children were evaluated. The intensity of p53 expression was not significantly increased after induction phase chemotherapy (p = 0.224, but surviving expression and the ratio of p53/surviving were significantly increased in the treatment group compared with the levels prior to chemotherapy (p = 0.002, p = 0.034, and there was a strong negative correlation between p53 and surviving after chemotherapy (r = −0.63, p = 0.049.

  3. How one TSH receptor antibody induces thyrocyte proliferation while another induces apoptosis.

    Science.gov (United States)

    Morshed, Syed A; Ma, Risheng; Latif, Rauf; Davies, Terry F

    2013-12-01

    Thyroid stimulating hormone (TSH) activates two major G-protein arms, Gsα and Gq leading to initiation of down-stream signaling cascades for survival, proliferation and production of thyroid hormones. Antibodies to the TSH receptor (TSHR-Abs), found in patients with Graves' disease, may have stimulating, blocking, or neutral actions on the thyroid cell. We have shown previously that such TSHR-Abs are distinct signaling imprints after binding to the TSHR and that such events can have variable functional consequences for the cell. In particular, there is a great contrast between stimulating (S) TSHR-Abs, which induce thyroid hormone synthesis and secretion as well as thyroid cell proliferation, compared to so called "neutral" (N) TSHR-Abs which may induce thyroid cell apoptosis via reactive oxygen species (ROS) generation. In the present study, using a rat thyrocyte (FRTL-5) ex vivo model system, our hypothesis was that while N-TSHR-Abs can induce apoptosis via activation of mitochondrial ROS (mROS), the S-TSHR-Abs are able to stimulate cell survival and avoid apoptosis by actively suppressing mROS. Using fluorescent microscopy, fluorometry, live cell imaging, immunohistochemistry and immunoblot assays, we have observed that S-TSHR-Abs do indeed suppress mROS and cellular stress and this suppression is exerted via activation of the PKA/CREB and AKT/mTOR/S6K signaling cascades. Activation of these signaling cascades, with the suppression of mROS, initiated cell proliferation. In sharp contrast, a failure to activate these signaling cascades with increased activation of mROS induced by N-TSHR-Abs resulted in thyroid cell apoptosis. Our current findings indicated that signaling diversity induced by different TSHR-Abs regulated thyroid cell fate. While S-TSHR-Abs may rescue cells from apoptosis and induce thyrocyte proliferation, N-TSHR-Abs aggravate the local inflammatory infiltrate within the thyroid gland, or in the retro-orbit, by inducing cellular apoptosis; a

  4. Resveratrol Inhibits the Proliferation of Neural Progenitor Cells and Hippocampal Neurogenesis*

    Science.gov (United States)

    Park, Hee Ra; Kong, Kyoung Hye; Yu, Byung Pal; Mattson, Mark P.; Lee, Jaewon

    2012-01-01

    Resveratrol is a phytoalexin and natural phenol that is present at relatively high concentrations in peanuts and red grapes and wine. Based upon studies of yeast and invertebrate models, it has been proposed that ingestion of resveratrol may also have anti-aging actions in mammals including humans. It has been suggested that resveratrol exerts its beneficial effects on health by activating the same cellular signaling pathways that are activated by dietary energy restriction (DR). Some studies have reported therapeutic actions of resveratrol in animal models of metabolic and neurodegenerative disorders. However, the effects of resveratrol on cell, tissue and organ function in healthy subjects are largely unknown. In the present study, we evaluated the potential effects of resveratrol on the proliferation and survival of neural progenitor cells (NPCs) in culture, and in the hippocampus of healthy young adult mice. Resveratrol reduced the proliferation of cultured mouse multi-potent NPCs, and activated AMP-activated protein kinase (AMPK), in a concentration-dependent manner. Administration of resveratrol to mice (1–10 mg/kg) resulted in activation of AMPK, and reduced the proliferation and survival of NPCs in the dentate gyrus of the hippocampus. Resveratrol down-regulated the levels of the phosphorylated form of cyclic AMP response element-binding protein (pCREB) and brain-derived neurotrophic factor (BDNF) in the hippocampus. Finally, resveratrol-treated mice exhibited deficits in hippocampus-dependent spatial learning and memory. Our findings suggest that resveratrol, unlike DR, adversely affects hippocampal neurogenesis and cognitive function by a mechanism involving activation of AMPK and suppression of CREB and BDNF signaling. PMID:23105098

  5. Basic fibroblast growth factor/vascular endothelial growth factor in the serum from severe burn patients stimulates the proliferation of cultured human umbilical cord mesenchymal stem cells via activation of Notch signaling pathways.

    Science.gov (United States)

    Liu, Ling-Ying; Hou, Yu-Sen; Chai, Jia-Ke; Hu, Quan; Duan, Hong-Jie; Yu, Yong-Hui; Yin, Hui-Nan; Hao, Dai-Feng; Feng, Guang; Li, Tao; Du, Jun-Dong

    2013-11-01

    Mesenchymal stem cells (MSCs) are the leading cellular constituents used in regenerative medicine. MSCs repair and reconstruct wounds of acute traumata and radiation-induced burns through proliferation, differentiation, and trophic activity. However, repair effect of MSCs on severe burn wounds remain to be clarified because severe burns are much more complex traumata than radiation-induced burns. Survival and proliferation of MSCs in microenvironments affected by severe burns are very important for improving wound repair/regeneration. This study aimed to elucidate the survival and proliferation effects and the potential proliferation mechanism of serum from severe burn patients (BPS) on human umbilical cord MSCs (hUCMSCs) in vitro. The hUCMSCs were isolated, cultured, and identified. Next, we evaluated the effects of BPS on cell numbers, cell cycle progression, cyclin D expression, and key proteins and genes of the Notch signaling pathway. Putative mechanisms underlying the proliferation of hUCMSCs were investigated. BPS markedly increased the number of hUCMSCs, and the results of the cell cycle studies indicated that BPS induced cell cycle progression into the M phase. Cyclin D expression was higher with BPS than in the control group. Moreover, Notch-1, a key determinant of hUCMSC activation and proliferation, and its target gene Hes-1 were overexpressed after BPS treatment. Proliferation numbers of hUCMSC, rate of proliferation period (G2/M+S), and the expression of cyclin D, Notch-1, and Hes-1 were markedly decreased by Notch signaling inhibitors (DAPT/GSI). In the case of BPS, basic fibroblast growth factor and vascular endothelial growth factor were the key factors that promoted hUCMSC proliferation. This study provides novel evidence for the role of BPS in the survival and rapid proliferation of hUCMSCs and suggests that these cells could be used for cell therapy-based clinical applications for treating severe burns. Furthermore, hUCMSC proliferation was

  6. Pursuing the identification of O(2) deprivation survival mechanisms in plants related to selective mRNA translation, hormone-independent cellular elongation and preparation for the arrival of oxygen.

    Science.gov (United States)

    Shingaki-Wells, Rachel N; Huang, Shaobai; Taylor, Nicolas L; Millar, A Harvey

    2011-10-01

    Anoxia can occur in crop fields when flooding forms a physical barrier that reduces oxygen availability. Rice, but not wheat, can germinate and elongate its coleoptile under anoxia, providing an excellent model for understanding mechanisms of anoxia tolerance. We have shown differential molecular responses of rice and wheat coleoptiles to anoxia and discovered novel metabolic adaptations in amino acid metabolism for tissue tolerance. In this addendum, we elaborate on our discussion to speculate on the functions of differentially regulated proteins and their possible roles in selective transcription and translation, alternative elongation strategies and preparedness for exposure to air. In addition, it is thought that rapid growth is a stress avoidance strategy; if adequate coleoptile growth occurs then plants can outgrow floodwaters to resume or begin aerobic respiration. An innate response mechanism to the arrival of air, and the oxidative stress inherent to this, would therefore be necessary in survival beyond the alleviation of anoxia. Thus, we emphasize the importance of recognizing anoxia as a multi-stage stress where responses otherwise considered counter-intuitive may have evolved as preparative defenses for when exposure to air occurs.

  7. Cell proliferation in carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, S.M.; Ellwein, L.B. (Univ. of Nebraska Medical Center, Omaha (USA))

    1990-08-31

    Chemicals that induce cancer at high doses in animal bioassays often fail to fit the traditional characterization of genotoxins. Many of these nongenotoxic compounds (such as sodium saccharin) have in common the property that they increase cell proliferation in the target organ. A biologically based, computerized description of carcinogenesis was used to show that the increase in cell proliferation can account for the carcinogenicity of nongenotoxic compounds. The carcinogenic dose-response relationship for genotoxic chemicals (such as 2-acetylaminofluorene) was also due in part to increased cell proliferation. Mechanistic information is required for determination of the existence of a threshold for the proliferative (and carcinogenic) response of nongenotoxic chemicals and the estimation of risk for human exposure.

  8. Predicting cellular growth from gene expression signatures.

    Directory of Open Access Journals (Sweden)

    Edoardo M Airoldi

    2009-01-01

    Full Text Available Maintaining balanced growth in a changing environment is a fundamental systems-level challenge for cellular physiology, particularly in microorganisms. While the complete set of regulatory and functional pathways supporting growth and cellular proliferation are not yet known, portions of them are well understood. In particular, cellular proliferation is governed by mechanisms that are highly conserved from unicellular to multicellular organisms, and the disruption of these processes in metazoans is a major factor in the development of cancer. In this paper, we develop statistical methodology to identify quantitative aspects of the regulatory mechanisms underlying cellular proliferation in Saccharomyces cerevisiae. We find that the expression levels of a small set of genes can be exploited to predict the instantaneous growth rate of any cellular culture with high accuracy. The predictions obtained in this fashion are robust to changing biological conditions, experimental methods, and technological platforms. The proposed model is also effective in predicting growth rates for the related yeast Saccharomyces bayanus and the highly diverged yeast Schizosaccharomyces pombe, suggesting that the underlying regulatory signature is conserved across a wide range of unicellular evolution. We investigate the biological significance of the gene expression signature that the predictions are based upon from multiple perspectives: by perturbing the regulatory network through the Ras/PKA pathway, observing strong upregulation of growth rate even in the absence of appropriate nutrients, and discovering putative transcription factor binding sites, observing enrichment in growth-correlated genes. More broadly, the proposed methodology enables biological insights about growth at an instantaneous time scale, inaccessible by direct experimental methods. Data and tools enabling others to apply our methods are available at http://function.princeton.edu/growthrate.

  9. Dedifferentiation and proliferation of mammalian cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Yiqiang Zhang

    2010-09-01

    Full Text Available It has long been thought that mammalian cardiomyocytes are terminally-differentiated and unable to proliferate. However, myocytes in more primitive animals such as zebrafish are able to dedifferentiate and proliferate to regenerate amputated cardiac muscle.Here we test the hypothesis that mature mammalian cardiomyocytes retain substantial cellular plasticity, including the ability to dedifferentiate, proliferate, and acquire progenitor cell phenotypes. Two complementary methods were used: 1 cardiomyocyte purification from rat hearts, and 2 genetic fate mapping in cardiac explants from bi-transgenic mice. Cardiomyocytes isolated from rodent hearts were purified by multiple centrifugation and Percoll gradient separation steps, and the purity verified by immunostaining and RT-PCR. Within days in culture, purified cardiomyocytes lost their characteristic electrophysiological properties and striations, flattened and began to divide, as confirmed by proliferation markers and BrdU incorporation. Many dedifferentiated cardiomyocytes went on to express the stem cell antigen c-kit, and the early cardiac transcription factors GATA4 and Nkx2.5. Underlying these changes, inhibitory cell cycle molecules were suppressed in myocyte-derived cells (MDCs, while microRNAs known to orchestrate proliferation and pluripotency increased dramatically. Some, but not all, MDCs self-organized into spheres and re-differentiated into myocytes and endothelial cells in vitro. Cell fate tracking of cardiomyocytes from 4-OH-Tamoxifen-treated double-transgenic MerCreMer/ZEG mouse hearts revealed that green fluorescent protein (GFP continues to be expressed in dedifferentiated cardiomyocytes, two-thirds of which were also c-kit(+.Contradicting the prevailing view that they are terminally-differentiated, postnatal mammalian cardiomyocytes are instead capable of substantial plasticity. Dedifferentiation of myocytes facilitates proliferation and confers a degree of stemness

  10. Profile of cell proliferation and apoptosis activated by the intrinsic and extrinsic pathways in the prostate of aging rats.

    Science.gov (United States)

    Gonzaga, Amanda C R; Campolina-Silva, Gabriel H; Werneck-Gomes, Hipácia; Moura-Cordeiro, Júnia D; Santos, Letícia C; Mahecha, Germán A B; Morais-Santos, Mônica; Oliveira, Cleida A

    2017-06-01

    Estrogens acting through the receptors ERα and ERβ participate in prostate normal growth and cancer. ERβ is highly expressed in the prostate epithelium, playing pro-apoptotic, anti-proliferative, and pro-differentiation roles. Apoptosis is activated by the intrinsic pathway after castration and by the extrinsic pathway after ERβ agonist treatment. This differential activation of apoptotic pathways is important since a major problem in the treatment of prostate cancer is the recurrence of tumors after androgen withdrawal. However, a comprehensive study about the pattern of apoptosis in the aging prostate is lacking, a knowledge gap that we aimed to address herein. Cellular age-related proliferative and apoptotic profiles of prostate tissue obtained from aging Wistar rats were evaluated. Cell death (caspase-3, -8, -9, TNFα) was assessed by immunohistochemistry, immunofluorescence, and TUNEL. Cell proliferation (MCM7) and cell survival factors (ERK1/2, p-ERK1/2, p-Akt, and NF-κB) were determined by immunohistochemistry. As the rats aged, the number of proliferating cells gradually reduced in the normal epithelium of all prostate lobes, while increasing in focal areas of intraepithelial proliferation. Interestingly, in areas of intraepithelial proliferation, we observed a reduction in the number of cells positive for caspase-3, -8, and -9. Regardless the animal's age, few prostate epithelial cells were positive for caspase-3, caspase-9, and TUNEL. In contrast, a progressive increase was seen in the positivity for caspase-8, especially in the atrophic epithelium of ventral prostate, which coincided with a reduction in TNFα immunoreaction. However, morphology of most caspase-8 positive cells suggests that they were not apoptotic. We also found reduced ERβ expression in the same areas. Possibly, low levels of the pro-apoptotic inductors TNFα and ERβ direct caspase-8 activity to an alternative pro-survival role in the atrophic epithelium. This hypothesis is

  11. Glycolysis and the pentose phosphate pathway are differentially associated with the dichotomous regulation of glioblastoma cell migration versus proliferation.

    Science.gov (United States)

    Kathagen-Buhmann, Annegret; Schulte, Alexander; Weller, Jonathan; Holz, Mareike; Herold-Mende, Christel; Glass, Rainer; Lamszus, Katrin

    2016-09-01

    The dichotomy between glioblastoma cell migration and proliferation is regulated by various parameters including oxygen tension. In glioblastoma stem-like cells, hypoxia induces downregulation of pentose phosphate pathway (PPP) enzymes and a flux shift towards glycolysis. We investigated whether the 2 parallel glucose metabolic pathways are intrinsically linked with cell function and whether these pathways are mechanistically involved in regulating functional programs. Enzyme expression, migration, and proliferation under hypoxia were studied in multiple cell types. Rapidly and slowly dividing or migrating glioblastoma cells were separated, and enzyme profiles were compared. Glucose-6-phosphate dehydrogenase (G6PD) and Aldolase C (ALDOC), the most strongly inversely regulated PPP and glycolysis enzymes, were knocked down by short hairpin RNA. Hypoxia caused downregulation of PPP enzymes and upregulation of glycolysis enzymes in a broad spectrum of cancer and nonneoplastic cells and consistently stimulated migration while reducing proliferation. PPP enzyme expression was increased in rapidly dividing glioblastoma cells, whereas glycolysis enzymes were decreased. Conversely, glycolysis enzymes were elevated in migrating cells, whereas PPP enzymes were diminished. Knockdown of G6PD reduced glioblastoma cell proliferation, whereas ALDOC knockdown decreased migration. Enzyme inhibitors had similar effects. G6PD knockdown in a highly proliferative but noninvasive glioblastoma cell line resulted in prolonged survival of mice with intracerebral xenografts, whereas ALDOC knockdown shortened survival. In a highly invasive glioblastoma xenograft model, tumor burden was unchanged by either knockdown. Cell function and metabolic state are coupled independently of hypoxia, and glucose metabolic pathways are causatively involved in regulating "go or grow" cellular programs. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro

  12. Cellular and Molecular Action of the Mitogenic Protein-Deamidating Toxin from Pasteurella multocida

    Science.gov (United States)

    Wilson, Brenda A.; Ho, Mengfei

    2011-01-01

    Summary The mitogenic toxin from Pasteurella multocida (PMT) is a member of the dermonecrotic toxin family, which includes toxins from Bordetella, E. coli and Yersinia. Members of the dermonecrotic toxin family modulate G-protein targets in host cells through selective deamidation and/or transglutamination of a critical active site glutamine residue in the G-protein target, which results in activation of the intrinsic GTPase activity. Structural and biochemical data point to the uniqueness of PMT among these toxins in its structure and action. Whereas the other dermonecrotic toxins act on small Rho GTPases, PMT acts on the α subunits of heterotrimeric Gq, Gi and G12/13 protein families. To date, experimental evidence support a model whereby PMT potently stimulates various mitogenic and survival pathways through activation of Gq and G12/13 signaling, ultimately leading to cellular proliferation, while strongly inhibiting pathways involved in cellular differentiation through activation of Gi signaling. The resulting cellular outcomes account for the global physiological effects observed during infection with toxinogenic P. multocida, as well as hint at potential long-term sequelae that may result from PMT exposure. PMID:21569202

  13. On differences in radiosensitivity estimation: TCP experiments versus survival curves. A theoretical study.

    Science.gov (United States)

    Stavrev, Pavel; Stavreva, Nadejda; Ruggieri, Ruggero; Nahum, Alan

    2015-08-07

    We have compared two methods of estimating the cellular radiosensitivity of a heterogeneous tumour, namely, via cell-survival and via tumour control probability (TCP) pseudo-experiments. It is assumed that there exists intra-tumour variability in radiosensitivity and that the tumour consists predominantly of radiosensitive cells and a small number of radio-resistant cells.Using a multi-component, linear-quadratic (LQ) model of cell kill, a pseudo-experimental cell-survival versus dose curve is derived. This curve is then fitted with a mono-component LQ model describing the response of a homogeneous cell population. For the assumed variation in radiosensitivity it is shown that the composite pseudo-experimental survival curve is well approximated by the survival curve of cells with uniform radiosensitivity.For the same initial cell radiosensitivity distribution several pseudo-experimental TCP curves are simulated corresponding to different fractionation regimes. The TCP model used accounts for clonogen proliferation during a fractionated treatment. The set of simulated TCP curves is then fitted with a mono-component TCP model. As in the cell survival experiment the fit with a mono-component model assuming uniform radiosensitivity is shown to be highly acceptable.However, the best-fit values of cellular radiosensitivity produced via the two methods are very different. The cell-survival pseudo-experiment yields a high radiosensitivity value, while the TCP pseudo-experiment shows that the dose-response is dominated by the most resistant sub-population in the tumour, even when this is just a small fraction of the total.

  14. Transient inter-cellular polymeric linker.

    Science.gov (United States)

    Ong, Siew-Min; He, Lijuan; Thuy Linh, Nguyen Thi; Tee, Yee-Han; Arooz, Talha; Tang, Guping; Tan, Choon-Hong; Yu, Hanry

    2007-09-01

    Three-dimensional (3D) tissue-engineered constructs with bio-mimicry cell-cell and cell-matrix interactions are useful in regenerative medicine. In cell-dense and matrix-poor tissues of the internal organs, cells support one another via cell-cell interactions, supplemented by small amount of the extra-cellular matrices (ECM) secreted by the cells. Here we connect HepG2 cells directly but transiently with inter-cellular polymeric linker to facilitate cell-cell interaction and aggregation. The linker consists of a non-toxic low molecular-weight polyethyleneimine (PEI) backbone conjugated with multiple hydrazide groups that can aggregate cells within 30 min by reacting with the aldehyde handles on the chemically modified cell-surface glycoproteins. The cells in the cellular aggregates proliferated; and maintained the cortical actin distribution of the 3D cell morphology while non-aggregated cells died over 7 days of suspension culture. The aggregates lost distinguishable cell-cell boundaries within 3 days; and the ECM fibers became visible around cells from day 3 onwards while the inter-cellular polymeric linker disappeared from the cell surfaces over time. The transient inter-cellular polymeric linker can be useful for forming 3D cellular and tissue constructs without bulk biomaterials or extensive network of engineered ECM for various applications.

  15. The Drosophila sterile-20 kinase slik controls cell proliferation and apoptosis during imaginal disc development.

    Directory of Open Access Journals (Sweden)

    David R Hipfner

    2003-11-01

    Full Text Available Cell proliferation and programmed cell death are closely controlled during animal development. Proliferative stimuli generally also induce apoptosis, and anti-apoptotic factors are required to allow net cell proliferation. Genetic studies in Drosophila have led to identification of a number of genes that control both processes, providing new insights into the mechanisms that coordinate cell growth, proliferation, and death during development and that fail to do so in diseases of cell proliferation. We present evidence that the Drosophila Sterile-20 kinase Slik promotes cell proliferation and controls cell survival. At normal levels, Slik provides survival cues that prevent apoptosis. Cells deprived of Slik activity can grow, divide, and differentiate, but have an intrinsic survival defect and undergo apoptosis even under conditions in which they are not competing with normal cells for survival cues. Like some oncogenes, excess Slik activity stimulates cell proliferation, but this is compensated for by increased cell death. Tumor-like tissue overgrowth results when apoptosis is prevented. We present evidence that Slik acts via Raf, but not via the canonical ERK pathway. Activation of Raf can compensate for the lack of Slik and support cell survival, but activation of ERK cannot. We suggest that Slik mediates growth and survival cues to promote cell proliferation and control cell survival during Drosophila development.

  16. Discoidin domain receptor 2 (DDR2) regulates proliferation of endochondral cells in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Ikuma; Hisaki, Tomoka; Sugiura, Koji; Naito, Kunihiko [Laboratory of Applied Genetics, Graduate School of Agricultural and Life Science, University of Tokyo, Tokyo 113-8657 (Japan); Kano, Kiyoshi, E-mail: kanokiyo@yamaguchi-u.ac.jp [Laboratory of Developmental Biology, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan. (Japan); Biomedical Science Center for Translational Research (BSCTR), The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi 753-8515 (Japan)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase. Black-Right-Pointing-Pointer DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. Black-Right-Pointing-Pointer We produced in vitro and in vivo model to better understand the role of DDR2. Black-Right-Pointing-Pointer DDR2 might play an inhibitory role in the proliferation of chondrocyte. -- Abstract: Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase that is activated by fibrillar collagens. DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. The decrement of endogenous DDR2 represses osteoblastic marker gene expression and osteogenic differentiation in murine preosteoblastic cells, but the functions of DDR2 in chondrogenic cellular proliferation remain unclear. To better understand the role of DDR2 signaling in cellular proliferation in endochondral ossification, we inhibited Ddr2 expression via the inhibitory effect of miRNA on Ddr2 mRNA (miDdr2) and analyzed the cellular proliferation and differentiation in the prechondrocyte ATDC5 cell lines. To investigate DDR2's molecular role in endochondral cellular proliferation in vivo, we also produced transgenic mice in which the expression of truncated, kinase dead (KD) DDR2 protein is induced, and evaluated the DDR2 function in cellular proliferation in chondrocytes. Although the miDdr2-transfected ATDC5 cell lines retained normal differentiation ability, DDR2 reduction finally promoted cellular proliferation in proportion to the decreasing ratio of Ddr2 expression, and it also promoted earlier differentiation to cartilage cells by insulin induction. The layer of hypertrophic chondrocytes in KD Ddr2 transgenic mice was not significantly thicker than that of normal littermates, but the layer of proliferative chondrocytes in KD-Ddr2 transgenic mice was significantly thicker than that of normal littermates

  17. Wnt signalling and the control of cellular metabolism

    Science.gov (United States)

    Sethi, Jaswinder K.; Vidal-Puig, Antonio

    2015-01-01

    At the cellular level, the biological processes of cell proliferation, growth arrest, differentiation and apoptosis are all tightly coupled to appropriate alterations in metabolic status. In the case of cell proliferation, this requires redirecting metabolic pathways to provide the fuel and basic components for new cells. Ultimately, the successful co-ordination of cell-specific biology with cellular metabolism underscores multicellular processes as diverse as embryonic development, adult tissue remodelling and cancer cell biology. The Wnt signalling network has been implicated in all of these areas. While each of the Wnt-dependent signalling pathways are being individually delineated in a range of experimental systems, our understanding of how they integrate and regulate cellular metabolism is still in its infancy. In the present review we reassess the roles of Wnt signalling in functionally linking cellular metabolism to tissue development and function. PMID:20226003

  18. Cellular host responses to gliomas.

    Directory of Open Access Journals (Sweden)

    Joseph Najbauer

    Full Text Available BACKGROUND: Glioblastoma multiforme (GBM is the most aggressive type of malignant primary brain tumors in adults. Molecular and genetic analysis has advanced our understanding of glioma biology, however mapping the cellular composition of the tumor microenvironment is crucial for understanding the pathology of this dreaded brain cancer. In this study we identified major cell populations attracted by glioma using orthotopic rodent models of human glioma xenografts. Marker-specific, anatomical and morphological analyses revealed a robust influx of host cells into the main tumor bed and tumor satellites. METHODOLOGY/PRINCIPAL FINDINGS: Human glioma cell lines and glioma spheroid orthotopic implants were used in rodents. In both models, the xenografts recruited large numbers of host nestin-expressing cells, which formed a 'network' with glioma. The host nestin-expressing cells appeared to originate in the subventricular zone ipsilateral to the tumor, and were clearly distinguishable from pericytes that expressed smooth muscle actin. These distinct cell populations established close physical contact in a 'pair-wise' manner and migrated together to the deeper layers of tumor satellites and gave rise to tumor vasculature. The GBM biopsy xenografts displayed two different phenotypes: (a low-generation tumors (first in vivo passage in rats were highly invasive and non-angiogenic, and host nestin-positive cells that infiltrated into these tumors displayed astrocytic or elongated bipolar morphology; (b high-generation xenografts (fifth passage had pronounced cellularity, were angiogenic with 'glomerulus-like' microvascular proliferations that contained host nestin-positive cells. Stromal cell-derived factor-1 and its receptor CXCR4 were highly expressed in and around glioma xenografts, suggesting their role in glioma progression and invasion. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate a robust migration of nestin-expressing host cells to glioma, which

  19. Wireless Cellular Mobile Communications

    OpenAIRE

    V. Zalud

    2002-01-01

    In this article is briefly reviewed the history of wireless cellular mobile communications, examined the progress in current second generation (2G) cellular standards and discussed their migration to the third generation (3G). The European 2G cellular standard GSM and its evolution phases GPRS and EDGE are described somewhat in detail. The third generation standard UMTS taking up on GSM/GPRS core network and equipped with a new advanced access network on the basis of code division multiple ac...

  20. Pharmacological or genetic blockade of the dopamine D3 receptor increases cell proliferation in the hippocampus of adult mice.

    Science.gov (United States)

    Egeland, Martin; Zhang, Xiaoqun; Millan, Mark J; Mocaer, Elisabeth; Svenningsson, Per

    2012-12-01

    Dopamine plays an important role in cellular processes controlling the functional and structural plasticity of neurons, as well as their generation and proliferation, both in the developing and the adult brain. The precise roles of individual dopamine receptors subtypes in adult neurogenesis remain poorly defined, although D3 receptors are known to be involved in neurogenesis in the subventricular zone. By contrast, very few studies have addressed the influence of dopamine and D3 receptors upon neurogenesis in the subgranular zone of the hippocampus, an issue addressed herein employing constitutive D3 receptor knockout mice, or chronic exposure to the preferential D3 receptor antagonist, S33138. D3 receptor knockout mice revealed increased baseline levels of cell proliferation and ongoing neurogenesis, as measured both using Ki-67 and doublecortin, whereas there was no difference in cell survival as measured by BrdU (5-bromo-2'-deoxyuridine). Chronic administration of S33138 was shown to be functionally active in enhancing levels of the plasticity-related molecule, delta-FosB, in the D3 receptor-rich nucleus accumbens. In accordance with the stimulated neurogenesis seen in D3 receptor knockout mice, S33138 increased proliferation in wild-type mice. These observations suggest that D3 receptors exert a tonic, constitutive inhibitory influence upon adult hippocampal neurogenesis. © 2012 The Authors Journal of Neurochemistry © 2012 International Society for Neurochemistry.

  1. Sulphoxythiocarbamates modify cysteine residues in HSP90 causing degradation of client proteins and inhibition of cancer cell proliferation.

    Science.gov (United States)

    Zhang, Y; Dayalan Naidu, S; Samarasinghe, K; Van Hecke, G C; Pheely, A; Boronina, T N; Cole, R N; Benjamin, I J; Cole, P A; Ahn, Y-H; Dinkova-Kostova, A T

    2014-01-07

    Heat shock protein 90 (HSP90) has a key role in the maintenance of the cellular proteostasis. However, HSP90 is also involved in stabilisation of oncogenic client proteins and facilitates oncogene addiction and cancer cell survival. The development of HSP90 inhibitors for cancer treatment is an area of growing interest as such agents can affect multiple pathways that are linked to all hallmarks of cancer. This study aimed to test the hypothesis that targeting cysteine residues of HSP90 will lead to degradation of client proteins and inhibition of cancer cell proliferation. Combining chemical synthesis, biological evaluation, and structure-activity relationship analysis, we identified a new class of HSP90 inhibitors. Click chemistry and protease-mass spectrometry established the sites of modification of the chaperone. The mildly electrophilic sulphoxythiocarbamate alkyne (STCA) selectively targets cysteine residues of HSP90, forming stable thiocarbamate adducts. Without interfering with the ATP-binding ability of the chaperone, STCA destabilises the client proteins RAF1, HER2, CDK1, CHK1, and mutant p53, and decreases proliferation of breast cancer cells. Addition of a phenyl or a tert-butyl group in tandem with the benzyl substituent at nitrogen increased the potency. A new compound, S-4, was identified as the most robust HSP90 inhibitor within a series of 19 derivatives. By virtue of their cysteine reactivity, sulphoxythiocarbamates target HSP90, causing destabilisation of its client oncoproteins and inhibiting cell proliferation.

  2. The ATM and ATR inhibitors CGK733 and caffeine suppress cyclin D1 levels and inhibit cell proliferation

    Directory of Open Access Journals (Sweden)

    Sunnerhagen Per

    2009-11-01

    Full Text Available Abstract The ataxia telangiectasia mutated (ATM and the ATM- related (ATR kinases play a central role in facilitating the resistance of cancer cells to genotoxic treatment regimens. The components of the ATM and ATR regulated signaling pathways thus provide attractive pharmacological targets, since their inhibition enhances cellular sensitivity to chemo- and radiotherapy. Caffeine as well as more specific inhibitors of ATM (KU55933 or ATM and ATR (CGK733 have recently been shown to induce cell death in drug-induced senescent tumor cells. Addition of these agents to cancer cells previously rendered senescent by exposure to genotoxins suppressed the ATM mediated p21 expression required for the survival of these cells. The precise molecular pharmacology of these agents however, is not well characterized. Herein, we report that caffeine, CGK733, and to a lesser extent KU55933, inhibit the proliferation of otherwise untreated human cancer and non-transformed mouse fibroblast cell lines. Exposure of human cancer cell lines to caffeine and CGK733 was associated with a rapid decline in cyclin D1 protein levels and a reduction in the levels of both phosphorylated and total retinoblastoma protein (RB. Our studies suggest that observations based on the effects of these compounds on cell proliferation and survival must be interpreted with caution. The differential effects of caffeine/CGK733 and KU55933 on cyclin D1 protein levels suggest that these agents will exhibit dissimilar molecular pharmacological profiles.

  3. GM-CSF produced by non-hematopoietic cells is required for early epithelial cell proliferation and repair of injured colonic mucosa1,2

    Science.gov (United States)

    Egea, Laia; McAllister, Christopher S.; Lakhdari, Omar; Minev, Ivelina; Shenouda, Steve; Kagnoff, Martin F.

    2012-01-01

    GM-CSF is a growth factor that promotes the survival and activation of macrophages and granulocytes, and dendritic cell (DC) differentiation and survival in vitro. The mechanism by which exogenous GM-CSF ameliorates the severity of Crohn’s disease in humans and colitis in murine models has been considered mainly to reflect its activity on myeloid cells. We used GM-CSF deficient (GM-CSF−/−) mice to probe the functional role of endogenous host-produced GM-CSF in a colitis model induced after injury to the colon epithelium. Dextran sodium sulfate (DSS) at doses that resulted in little epithelial damage and mucosal ulceration in wild type (WT) mice resulted in marked colon ulceration and delayed ulcer healing in GM-CSF−/− mice. Colon crypt epithelial cell proliferation in vivo was significantly decreased in GM-CSF−/− mice at early times after DSS injury. This was paralleled by decreased expression of crypt epithelial cell genes involved in cell cycle, proliferation, and wound healing. Decreased crypt cell proliferation and delayed ulcer healing in GM-CSF−/− mice were rescued by exogenous GM-CSF, indicating the lack of a developmental abnormality in the epithelial cell proliferative response in those mice. Non-hematopoietic cells and not myeloid cells produced the GM-CSF important for colon epithelial proliferation after DSS-induced injury as revealed by bone marrow chimera and DC depletion experiments, with colon epithelial cells being the cellular source of GM-CSF. Endogenous epithelial cell produced GM-CSF has a novel non-redundant role in facilitating epithelial cell proliferation and ulcer healing in response to injury of the colon crypt epithelium. PMID:23325885

  4. Histone variant H2A.Z.2 mediates proliferation and drug sensitivity of malignant melanoma

    Science.gov (United States)

    Vardabasso, Chiara; Gaspar-Maia, Alexandre; Hasson, Dan; Pünzeler, Sebastian; Valle-Garcia, David; Straub, Tobias; Keilhauer, Eva C.; Strub, Thomas; Dong, Joanna; Panda, Taniya; Chung, Chi-Yeh; Yao, Jonathan L.; Singh, Rajendra; Segura, Miguel F.; Fontanals-Cirera, Barbara; Verma, Amit; Mann, Matthias; Hernando, Eva; Hake, Sandra B.; Bernstein, Emily

    2015-01-01

    SUMMARY Histone variants are emerging as key regulatory molecules in cancer. Here we report a novel role for the H2A.Z isoform H2A.Z.2 as a driver of malignant melanoma. H2A.Z.2 is highly expressed in metastatic melanoma, correlates with decreased patient survival, and is required for cellular proliferation. Our integrated genomic analyses reveal that H2A.Z.2 controls the transcriptional output of E2F target genes in melanoma cells. These genes are highly expressed and display a distinct signature of H2A.Z occupancy. We identify BRD2 as an H2A.Z interacting protein, whose levels are also elevated in melanoma. We further demonstrate that H2A.Z.2 regulated genes are bound by BRD2 and E2F1 in a H2A.Z.2-dependent manner. Importantly, H2A.Z.2 deficiency sensitizes melanoma cells to chemotherapy and targeted therapies. Collectively, our findings implicate H2A.Z.2 as a mediator of cell proliferation and drug sensitivity in malignant melanoma, holding translational potential for novel therapeutic strategies. PMID:26051178

  5. Survival Analysis

    CERN Document Server

    Miller, Rupert G

    2011-01-01

    A concise summary of the statistical methods used in the analysis of survival data with censoring. Emphasizes recently developed nonparametric techniques. Outlines methods in detail and illustrates them with actual data. Discusses the theory behind each method. Includes numerous worked problems and numerical exercises.

  6. Modelling survival

    DEFF Research Database (Denmark)

    Ashauer, Roman; Albert, Carlo; Augustine, Starrlight

    2016-01-01

    well GUTS, calibrated with short-term survival data of Gammarus pulex exposed to four pesticides, can forecast effects of longer-term pulsed exposures. Thirdly, we tested the ability of GUTS to estimate 14-day median effect concentrations of malathion for a range of species and use these estimates...

  7. Survival and Death Signals Can Be Used to Predict when Oncogene Inactivation Will Elicit Oncogene Addiction

    Science.gov (United States)

    Tran, Phuoc T.; Bendapudi, Pavan K.; Lin, H. Jill; Choi, Peter; Koh, Shan; Chen, Joy; Horng, George; Hughes, Nicholas P.; Schwartz, Lawrence H.; Miller, Vincent A.; Kawashima, Toshiyuki; Kitamura, Toshio; Paik, David; Felsher, Dean W.

    2012-01-01

    Cancers can exhibit dramatic tumor regression following oncogene inhibition through the phenomenon of “oncogene addiction”. The ability to predict when a tumor will exhibit oncogene addiction would be useful in the development of targeted therapeutics. Oncogene addiction is likely the consequence of many cellular programs. However, we reasoned that many of these inputs may converge on aggregate survival and death signals. To test this, we measured the sequence of changes that occur upon oncogene inactivation in conditional genetically engineered mouse models of K-rasG12D- or MYC-induced lung tumors and lymphoma. We combined quantitative imaging with an in situ analysis of biomarkers of proliferation and apoptosis. Indeed, oncogene addiction could be modeled as differential changes in intracellular survival and death signals following oncogene inactivation. Our model used different imaging methods (CT and bioluminescence imaging) and histochemical markers of proliferation and apoptosis (Ki-67 and caspase 3) to blindly predict the differential in dynamics of several pro-survival and pro-death signaling factors (phosphorylated Erk1/2, Akt1, Stat3/5 and p38) that contribute to the aggregate survival and death signals. The model was predictive of different oncogenes (K-rasG12D and MYC) in multiple tumor types (lung and lymphoma). Furthermore, we could predict the influence of specific genetic lesions (p53-/-, Stat3-d358L and myr-Akt1) on tumor regression upon oncogene inactivation. Finally, our model could utilize quantitative imaging data to predict both EGFR genotype and progression-free survival in human patients with lung cancer shortly after the initiation of treatment with the targeted therapy erlotinib. Hence, the consequences of oncogene inactivation can be accurately modeled based on a relatively small number of parameters that may predict when targeted therapeutics will elicit oncogene addiction. PMID:21974937

  8. Proliferation and fission of peroxisomes - An update.

    Science.gov (United States)

    Schrader, Michael; Costello, Joseph L; Godinho, Luis F; Azadi, Afsoon S; Islinger, Markus

    2016-05-01

    In mammals, peroxisomes perform crucial functions in cellular metabolism, signalling and viral defense which are essential to the health and viability of the organism. In order to achieve this functional versatility peroxisomes dynamically respond to molecular cues triggered by changes in the cellular environment. Such changes elicit a corresponding response in peroxisomes, which manifests itself as a change in peroxisome number, altered enzyme levels and adaptations to the peroxisomal structure. In mammals the generation of new peroxisomes is a complex process which has clear analogies to mitochondria, with both sharing the same division machinery and undergoing a similar division process. How the regulation of this division process is integrated into the cell's response to different stimuli, the signalling pathways and factors involved, remains somewhat unclear. Here, we discuss the mechanism of peroxisomal fission, the contributions of the various division factors and examine the potential impact of post-translational modifications, such as phosphorylation, on the proliferation process. We also summarize the signalling process and highlight the most recent data linking signalling pathways with peroxisome proliferation.

  9. Fatty acid metabolites in rapidly proliferating breast cancer.

    Directory of Open Access Journals (Sweden)

    Joseph T O'Flaherty

    Full Text Available Breast cancers that over-express a lipoxygenase or cyclooxygenase are associated with poor survival possibly because they overproduce metabolites that alter the cancer's malignant behaviors. However, these metabolites and behaviors have not been identified. We here identify which metabolites among those that stimulate breast cancer cell proliferation in vitro are associated with rapidly proliferating breast cancer.We used selective ion monitoring-mass spectrometry to quantify in the cancer and normal breast tissue of 27 patients metabolites that stimulate (15-, 12-, 5-hydroxy-, and 5-oxo-eicosatetraenoate, 13-hydroxy-octadecaenoate [HODE] or inhibit (prostaglandin [PG]E2 and D2 breast cancer cell proliferation. We then related their levels to each cancer's proliferation rate as defined by its Mib1 score.13-HODE was the only metabolite strongly, significantly, and positively associated with Mib1 scores. It was similarly associated with aggressive grade and a key component of grade, mitosis, and also trended to be associated with lymph node metastasis. PGE2 and PGD2 trended to be negatively associated with these markers. No other metabolite in cancer and no metabolite in normal tissue had this profile of associations.Our data fit a model wherein the overproduction of 13-HODE by 15-lipoxygenase-1 shortens breast cancer survival by stimulating its cells to proliferate and possibly metastasize; no other oxygenase-metabolite pathway, including cyclooxygenase-PGE2/D2 pathways, uses this specific mechanism to shorten survival.

  10. NSAIDs and Cell Proliferation in Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Raj Ettarh

    2010-06-01

    Full Text Available Colon cancer is common worldwide and accounts for significant morbidity and mortality in patients. Fortunately, epidemiological studies have demonstrated that continuous therapy with NSAIDs offers real promise of chemoprevention and adjunct therapy for colon cancer patients. Tumour growth is the result of complex regulation that determines the balance between cell proliferation and cell death. How NSAIDs affect this balance is important for understanding and improving treatment strategies and drug effectiveness. NSAIDs inhibit proliferation and impair the growth of colon cancer cell lines when tested in culture in vitro and many NSAIDs also prevent tumorigenesis and reduce tumour growth in animal models and in patients, but the relationship to inhibition of tumour cell proliferation is less convincing, principally due to gaps in the available data. High concentrations of NSAIDs are required in vitro to achieve cancer cell inhibition and growth retardation at varying time-points following treatment. However, the results from studies with colon cancer cell xenografts are promising and, together with better comparative data on anti-proliferative NSAID concentrations and doses (for in vitro and in vivo administration, could provide more information to improve our understanding of the relationships between these agents, dose and dosing regimen, and cellular environment.

  11. JPRS Report, Proliferation Issues

    Science.gov (United States)

    1992-05-27

    JPRS-TND-92-016 27 MAY 1992 JPRS Repor Proliferation Issues ÄBpxovea tcz pursue ieiaaM| Ipfe. fötmbuasa OsüoaÜBd .^L ■ — —— au »** 19980112...6 MOROCCO Berrada on Proposed Nuclear Power Plant [ MAROC SOIR 22 Apr] 6 JPRS-TND-92-016 27 May 1992 2 CENTRAL EURASIA Proposals on...three days of talks here on normalizing relations with Japan, which were largely stalemated over Tokyo’s demand for Pyongyang’s assurance that it did

  12. Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lingling [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Zhao, Yingmin [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Gu, Xin; Wang, Jijun; Pang, Lei; Zhang, Yanqing; Li, Yaoyao; Jia, Xiaoqin; Wang, Xin [Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Gu, Jian [Department of Hematology, Yangzhou University School of Clinical Medicine, Yangzhou 225001 (China); Yu, Duonan, E-mail: duonan@yahoo.com [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Disease, Yangzhou 225001 (China); Institute of Comparative Medicine, Yangzhou University, Yangzhou 225001 (China); Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Disease and Zoonosis, Yangzhou 225001 (China)

    2016-06-10

    Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feeder layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. - Highlights: • LPS alone in culture is required for the proliferation of murine myeloid tumor cells. • Bone marrow stromal cells as a feeder layer is also required for the proliferation of myeloid tumor cells. • However, the growth of myeloid tumor cells is inhibited when LPS and stromal cells are both available in culture. • Thus LPS can either facilitate or attenuate tumor growth through its direct effect or modulation of tumor microenvironment.

  13. Identification of chimeric antigen receptors that mediate constitutive or inducible proliferation of T cells.

    Science.gov (United States)

    Frigault, Matthew J; Lee, Jihyun; Basil, Maria Ciocca; Carpenito, Carmine; Motohashi, Shinichiro; Scholler, John; Kawalekar, Omkar U; Guedan, Sonia; McGettigan, Shannon E; Posey, Avery D; Ang, Sonny; Cooper, Laurence J N; Platt, Jesse M; Johnson, F Brad; Paulos, Chrystal M; Zhao, Yangbing; Kalos, Michael; Milone, Michael C; June, Carl H

    2015-04-01

    This study compared second-generation chimeric antigen receptors (CAR) encoding signaling domains composed of CD28, ICOS, and 4-1BB (TNFRSF9). Here, we report that certain CARs endow T cells with the ability to undergo long-term autonomous proliferation. Transduction of primary human T cells with lentiviral vectors encoding some of the CARs resulted in sustained proliferation for up to 3 months following a single stimulation through the T-cell receptor (TCR). Sustained numeric expansion was independent of cognate antigen and did not require the addition of exogenous cytokines or feeder cells after a single stimulation of the TCR and CD28. Results from gene array and functional assays linked sustained cytokine secretion and expression of T-bet (TBX21), EOMES, and GATA-3 to the effect. Sustained expression of the endogenous IL2 locus has not been reported in primary T cells. Sustained proliferation was dependent on CAR structure and high expression, the latter of which was necessary but not sufficient. The mechanism involves constitutive signaling through NF-κB, AKT, ERK, and NFAT. The propagated CAR T cells retained a diverse TCR repertoire, and cellular transformation was not observed. The CARs with a constitutive growth phenotype displayed inferior antitumor effects and engraftment in vivo. Therefore, the design of CARs that have a nonconstitutive growth phenotype may be a strategy to improve efficacy and engraftment of CAR T cells. The identification of CARs that confer constitutive or nonconstitutive growth patterns may explain observations that CAR T cells have differential survival patterns in clinical trials. ©2015 American Association for Cancer Research.

  14. Proliferation and recapitulation of developmental patterning associated with regulative regeneration of the spinal cord neural tube.

    Science.gov (United States)

    Halasi, Gabor; Søviknes, Anne Mette; Sigurjonsson, Olafur; Glover, Joel C

    2012-05-01

    Developmental patterning during regulative regeneration of the chicken embryo spinal neural tube was characterized by assessing proliferation and the expression of transcription factors specific to neural progenitor and postmitotic neuron populations. One to several segments of the thoracolumbar neural tube were selectively excised unilaterally to initiate regeneration. The capacity for regeneration depended on the stage when ablation was performed and the extent of tissue removed. 20% of surviving embryos exhibited complete regulative regeneration, wherein the missing hemi-neural tube was reconstituted to normal size and morphology. Fate-mapping of proliferative adjacent tissue indicated contributions from the opposite side of the neural tube and potentially from the ipsilateral neural tube rostral and caudal to the lesion. Application of the thymidine analog EdU (5-ethynyl-2'-deoxyuridine) demonstrated a moderate increase in cell proliferation in lesioned relative to control embryos, and quantitative PCR demonstrated a parallel moderate increase in transcription of proliferation-related genes. Mathematical calculation showed that such modest increases are sufficient to account for the amount of regenerated tissue. Within the regenerated neural tube the expression pattern of progenitor-specific transcription factors was recapitulated in the separate advancing ventral and dorsal fronts of regeneration, with no evidence of abnormal mixing of progenitor subpopulations, indicating that graded patterning mechanisms do not require continuity of neural tube tissue along the dorsoventral axis and do not involve a sorting out of committed progenitors. Upon completion of the regeneration process, the pattern of neuron-specific transcription factor expression was essentially normal. Modest deficits in the numbers of transcription factor-defined neuron types were evident in the regenerated tissue, increasing particularly in dorsal neuron types with later lesions. These

  15. Heterogeneous cellular networks

    CERN Document Server

    Hu, Rose Qingyang

    2013-01-01

    A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management i

  16. Nominal Cellular Automata

    Directory of Open Access Journals (Sweden)

    Tommaso Bolognesi

    2016-08-01

    Full Text Available The emerging field of Nominal Computation Theory is concerned with the theory of Nominal Sets and its applications to Computer Science. We investigate here the impact of nominal sets on the definition of Cellular Automata and on their computational capabilities, with a special focus on the emergent behavioural properties of this new model and their significance in the context of computation-oriented interpretations of physical phenomena. A preliminary investigation of the relations between Nominal Cellular Automata and Wolfram's Elementary Cellular Automata is also carried out.

  17. Antizyme Inhibitor 2 : A Novel Regulator of Cellular Polyamine Homeostasis

    OpenAIRE

    Kanerva, Kristiina

    2010-01-01

    Polyamines are organic polycations that participate in various physiological functions, including cell proliferation, differentiation and apoptosis. Cellular polyamines originate from endogenous biosynthesis and exogenous sources. Their subcellular pool is under strict control, achieved by regulating their uptake and metabolism. Polyamine-induced proteins called antizymes (AZ) act as key regulators of intracellular polyamine concentration. They regulate both the transport of polyamines and th...

  18. Determining Lineage Pathways from Cellular Barcoding Experiments

    Directory of Open Access Journals (Sweden)

    Leïla Perié

    2014-02-01

    Full Text Available Cellular barcoding and other single-cell lineage-tracing strategies form experimental methodologies for analysis of in vivo cell fate that have been instrumental in several significant recent discoveries. Due to the highly nonlinear nature of proliferation and differentiation, interrogation of the resulting data for evaluation of potential lineage pathways requires a new quantitative framework complete with appropriate statistical tests. Here, we develop such a framework, illustrating its utility by analyzing data from barcoded multipotent cells of the blood system. This application demonstrates that the data require additional paths beyond those found in the classical model, which leads us to propose that hematopoietic differentiation follows a loss of potential mechanism and to suggest further experiments to test this deduction. Our quantitative framework can evaluate the compatibility of lineage trees with barcoded data from any proliferating and differentiating cell system.

  19. Transcription Factors in the Cellular Response to Charged Particle Exposure

    Science.gov (United States)

    Hellweg, Christine E.; Spitta, Luis F.; Henschenmacher, Bernd; Diegeler, Sebastian; Baumstark-Khan, Christa

    2016-01-01

    Charged particles, such as carbon ions, bear the promise of a more effective cancer therapy. In human spaceflight, exposure to charged particles represents an important risk factor for chronic and late effects such as cancer. Biological effects elicited by charged particle exposure depend on their characteristics, e.g., on linear energy transfer (LET). For diverse outcomes (cell death, mutation, transformation, and cell-cycle arrest), an LET dependency of the effect size was observed. These outcomes result from activation of a complex network of signaling pathways in the DNA damage response, which result in cell-protective (DNA repair and cell-cycle arrest) or cell-destructive (cell death) reactions. Triggering of these pathways converges among others in the activation of transcription factors, such as p53, nuclear factor κB (NF-κB), activated protein 1 (AP-1), nuclear erythroid-derived 2-related factor 2 (Nrf2), and cAMP responsive element binding protein (CREB). Depending on dose, radiation quality, and tissue, p53 induces apoptosis or cell-cycle arrest. In low LET radiation therapy, p53 mutations are often associated with therapy resistance, while the outcome of carbon ion therapy seems to be independent of the tumor’s p53 status. NF-κB is a central transcription factor in the immune system and exhibits pro-survival effects. Both p53 and NF-κB are activated after ionizing radiation exposure in an ataxia telangiectasia mutated (ATM)-dependent manner. The NF-κB activation was shown to strongly depend on charged particles’ LET, with a maximal activation in the LET range of 90–300 keV/μm. AP-1 controls proliferation, senescence, differentiation, and apoptosis. Nrf2 can induce cellular antioxidant defense systems, CREB might also be involved in survival responses. The extent of activation of these transcription factors by charged particles and their interaction in the cellular radiation response greatly influences the destiny of the irradiated and also

  20. Transcription Factors in the Cellular Response to Charged Particle Exposure

    Directory of Open Access Journals (Sweden)

    Christine Elisabeth Hellweg

    2016-03-01

    Full Text Available Charged particles such as carbon ions bear the promise of a more effective cancer therapy. In human spaceflight, exposure to charged particles represents an important risk factor for chronic and late effects such as cancer. Biological effects elicited by charged particle exposure depend on their characteristics, e.g. on linear energy transfer (LET. For diverse outcomes (cell death, mutation, transformation, cell cycle arrest, an LET dependency of the effect size was observed. These outcomes result from activation of a complex network of signaling pathways in the DNA damage response, which result in cell-protective (DNA repair, cell cycle arrest or cell-destructive (cell death reactions. Triggering of these pathways converges amongst others in the activation of transcription factors such as p53, Nuclear Factor kappaB (NF-kappaB, activated protein 1 (AP-1, nuclear erythroid-derived 2-related factor 2 (Nrf2 and Cyclic-Nucleotide Response Element-Binding Protein (CREB. Depending on dose, radiation quality and tissue, p53 induces apoptosis or cell cycle arrest. In low-LET radiation therapy, p53 mutations are often associated with therapy resistance, while the outcome of carbon ion therapy seems to be independent of the tumor’s p53 status. NF-kappaB is a central transcription factor in the immune system and exhibits pro-survival effects. Both p53 and NF-kappaB are activated after ionizing radiation exposure in an ATM dependent manner. The NF-kappaB activation was shown to strongly depend on charged particles’ LET, with a maximal activation in the LET range of 90-300 keV/µm. AP-1 controls proliferation, senescence, differentiation and apoptosis. Nrf2 can induce cellular antioxidant defense systems, CREB might also be involved in survival responses. The extent of activation of these transcription factors by charged particles and their interaction in the cellular radiation response greatly influences the destiny of the irradiated and also

  1. Cellular magnesium homeostasis.

    Science.gov (United States)

    Romani, Andrea M P

    2011-08-01

    Magnesium, the second most abundant cellular cation after potassium, is essential to regulate numerous cellular functions and enzymes, including ion channels, metabolic cycles, and signaling pathways, as attested by more than 1000 entries in the literature. Despite significant recent progress, however, our understanding of how cells regulate Mg(2+) homeostasis and transport still remains incomplete. For example, the occurrence of major fluxes of Mg(2+) in either direction across the plasma membrane of mammalian cells following metabolic or hormonal stimuli has been extensively documented. Yet, the mechanisms ultimately responsible for magnesium extrusion across the cell membrane have not been cloned. Even less is known about the regulation in cellular organelles. The present review is aimed at providing the reader with a comprehensive and up-to-date understanding of the mechanisms enacted by eukaryotic cells to regulate cellular Mg(2+) homeostasis and how these mechanisms are altered under specific pathological conditions. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Hijacking cellular garbage cans.

    Science.gov (United States)

    Welsch, Sonja; Locker, Jacomine Krijnse

    2010-06-25

    Viruses are perfect opportunists that have evolved to modify numerous cellular processes in order to complete their replication cycle in the host cell. An article by Reggiori and coworkers in this issue of Cell Host & Microbe reveals how coronaviruses can divert a cellular quality control pathway that normally functions in degradation of mis-folded proteins to replicate the viral genome. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  3. Modeling cellular systems

    CERN Document Server

    Matthäus, Franziska; Pahle, Jürgen

    2017-01-01

    This contributed volume comprises research articles and reviews on topics connected to the mathematical modeling of cellular systems. These contributions cover signaling pathways, stochastic effects, cell motility and mechanics, pattern formation processes, as well as multi-scale approaches. All authors attended the workshop on "Modeling Cellular Systems" which took place in Heidelberg in October 2014. The target audience primarily comprises researchers and experts in the field, but the book may also be beneficial for graduate students.

  4. Proliferation: myth or reality?; La proliferation: mythe ou realite?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This article analyzes the proliferation approach, its technical condition and political motivation, and the share between the myth (political deception, assumptions and extrapolations) and the reality of proliferation. Its appreciation is complicated by the irrational behaviour of some political actors and by the significant loss of the non-use taboo. The control of technologies is an important element for proliferation slowing down but an efficient and autonomous intelligence system remains indispensable. (J.S.)

  5. Innovations’ Survival

    Directory of Open Access Journals (Sweden)

    Jakub Tabas

    2016-01-01

    Full Text Available Innovations currently represent a tool of maintaining the going concern of a business entity and its competitiveness. However, effects of innovations are not infinite and if an innovation should constantly preserve a life of business entity, it has to be a continual chain of innovations, i.e. continual process. Effective live of a single innovation is limited while the limitation is derived especially from industry. The paper provides the results of research on innovations effects in the financial performance of small and medium-sized enterprises in the Czech Republic. Objective of this paper is to determine the length and intensity of the effects of technical innovations in company’s financial performance. The economic effect of innovations has been measured at application of company’s gross production power while the Deviation Analysis has been applied for three years’ time series. Subsequently the Survival Analysis has been applied. The analyses are elaborated for three statistical samples of SMEs constructed in accordance to the industry. The results obtained show significant differences in innovations’ survival within these three samples of enterprises then. The results are quite specific for the industries, and are confronted and discussed with the results of authors’ former research on the issue.

  6. Prodrug Approach for Increasing Cellular Glutathione Levels

    Directory of Open Access Journals (Sweden)

    Ivana Cacciatore

    2010-03-01

    Full Text Available Reduced glutathione (GSH is the most abundant non-protein thiol in mammalian cells and the preferred substrate for several enzymes in xenobiotic metabolism and antioxidant defense. It plays an important role in many cellular processes, such as cell differentiation, proliferation and apoptosis. GSH deficiency has been observed in aging and in a wide range of pathologies, including neurodegenerative disorders and cystic fibrosis (CF, as well as in several viral infections. Use of GSH as a therapeutic agent is limited because of its unfavorable biochemical and pharmacokinetic properties. Several reports have provided evidence for the use of GSH prodrugs able to replenish intracellular GSH levels. This review discusses different strategies for increasing GSH levels by supplying reversible bioconjugates able to cross the cellular membrane more easily than GSH and to provide a source of thiols for GSH synthesis.

  7. Emerging roles of extracellular vesicles in cellular senescence and aging.

    Science.gov (United States)

    Takasugi, Masaki

    2018-02-01

    Cellular senescence is a cellular program that prevents the proliferation of cells at risk of neoplastic transformation. On the other hand, age-related accumulation of senescent cells promotes aging at least partially due to the senescence-associated secretory phenotype, whereby cells secrete high levels of inflammatory cytokines, chemokines, and matrix metalloproteinases. Emerging evidence, however, indicates that extracellular vesicles (EVs) are important mediators of the effects of senescent cells on their microenvironment. Senescent cells secrete more EphA2 and DNA via EVs, which can promote cancer cell proliferation and inflammation, respectively. Extracellular vesicles secreted from DNA-damaged cells can also affect telomere regulation. Furthermore, it has now become clear that EVs actually play important roles in many aspects of aging. This review is intended to summarize these recent progresses, with emphasis on relationships between cellular senescence and EVs. © 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  8. 3D-engineering of Cellularized Conduits for Peripheral Nerve Regeneration

    Science.gov (United States)

    Hu, Yu; Wu, Yao; Gou, Zhiyuan; Tao, Jie; Zhang, Jiumeng; Liu, Qianqi; Kang, Tianyi; Jiang, Shu; Huang, Siqing; He, Jiankang; Chen, Shaochen; Du, Yanan; Gou, Maling

    2016-08-01

    Tissue engineered conduits have great promise for bridging peripheral nerve defects by providing physical guiding and biological cues. A flexible method for integrating support cells into a conduit with desired architectures is wanted. Here, a 3D-printing technology is adopted to prepare a bio-conduit with designer structures for peripheral nerve regeneration. This bio-conduit is consisted of a cryopolymerized gelatin methacryloyl (cryoGelMA) gel cellularized with adipose-derived stem cells (ASCs). By modeling using 3D-printed “lock and key” moulds, the cryoGelMA gel is structured into conduits with different geometries, such as the designed multichannel or bifurcating and the personalized structures. The cryoGelMA conduit is degradable and could be completely degraded in 2-4 months in vivo. The cryoGelMA scaffold supports the attachment, proliferation and survival of the seeded ASCs, and up-regulates the expression of their neurotrophic factors mRNA in vitro. After implanted in a rat model, the bio-conduit is capable of supporting the re-innervation across a 10 mm sciatic nerve gap, with results close to that of the autografts in terms of functional and histological assessments. The study describes an indirect 3D-printing technology for fabricating cellularized designer conduits for peripheral nerve regeneration, and could lead to the development of future nerve bio-conduits for clinical use.

  9. Cellular and ultrastructural characterization of the grey-morph phenotype in southern right whales (Eubalaena australis).

    Science.gov (United States)

    Eroh, Guy D; Clayton, Fred C; Florell, Scott R; Cassidy, Pamela B; Chirife, Andrea; Marón, Carina F; Valenzuela, Luciano O; Campbell, Michael S; Seger, Jon; Rowntree, Victoria J; Leachman, Sancy A

    2017-01-01

    Southern right whales (SRWs, Eubalena australis) are polymorphic for an X-linked pigmentation pattern known as grey morphism. Most SRWs have completely black skin with white patches on their bellies and occasionally on their backs; these patches remain white as the whale ages. Grey morphs (previously referred to as partial albinos) appear mostly white at birth, with a splattering of rounded black marks; but as the whales age, the white skin gradually changes to a brownish grey color. The cellular and developmental bases of grey morphism are not understood. Here we describe cellular and ultrastructural features of grey-morph skin in relation to that of normal, wild-type skin. Melanocytes were identified histologically and counted, and melanosomes were measured using transmission electron microscopy. Grey-morph skin had fewer melanocytes when compared to wild-type skin, suggesting reduced melanocyte survival, migration, or proliferation in these whales. Grey-morph melanocytes had smaller melanosomes relative to wild-type skin, normal transport of melanosomes to surrounding keratinocytes, and normal localization of melanin granules above the keratinocyte nuclei. These findings indicate that SRW grey-morph pigmentation patterns are caused by reduced numbers of melanocytes in the skin, as well as by reduced amounts of melanin production and/or reduced sizes of mature melanosomes. Grey morphism is distinct from piebaldism and albinism found in other species, which are genetic pigmentation conditions resulting from the local absence of melanocytes, or the inability to synthesize melanin, respectively.

  10. Cellular and Developmental Biology of TRPM7 Channel-Kinase: Implicated Roles in Cancer

    Directory of Open Access Journals (Sweden)

    Nelson S. Yee

    2014-07-01

    Full Text Available The transient receptor potential melastatin-subfamily member 7 (TRPM7 is a ubiquitously expressed cation-permeable ion channel with intrinsic kinase activity that plays important roles in various physiological functions. Biochemical and electrophysiological studies, in combination with molecular analyses of TRPM7, have generated insights into its functions as a cellular sensor and transducer of physicochemical stimuli. Accumulating evidence indicates that TRPM7 channel-kinase is essential for cellular processes, such as proliferation, survival, differentiation, growth, and migration. Experimental studies in model organisms, such as zebrafish, mouse, and frog, have begun to elucidate the pleiotropic roles of TRPM7 during embryonic development from gastrulation to organogenesis. Aberrant expression and/or activity of the TRPM7 channel-kinase have been implicated in human diseases including a variety of cancer. Studying the functional roles of TRPM7 and the underlying mechanisms in normal cells and developmental processes is expected to help understand how TRPM7 channel-kinase contributes to pathogenesis, such as malignant neoplasia. On the other hand, studies of TRPM7 in diseases, particularly cancer, will help shed new light in the normal functions of TRPM7 under physiological conditions. In this article, we will provide an updated review of the structural features and biological functions of TRPM7, present a summary of current knowledge of its roles in development and cancer, and discuss the potential of TRPM7 as a clinical biomarker and therapeutic target in malignant diseases.

  11. Perfluorinated alginate for cellular encapsulation.

    Science.gov (United States)

    Gattás-Asfura, Kerim M; Fraker, Christopher A; Stabler, Cherie L

    2012-08-01

    Molecules of pentadecafluorooctanoyl chloride (PFC) were grafted onto alginate (Alg) using a linear poly(ethylene glycol) linker and amide bonds. The resulting Alg-PFC material was characterized by proton nuclear magnetic resonance and infrared spectroscopies. The degree of PFC functionalization significantly influenced the physical and chemical properties of Alg-PFC, particularly when the resulting polymer was ionically crosslinked into hydrogels. Alg-PFC hydrogel beads fabricated via Ba(2+) crosslinking were found to match the permeability properties of control alginate beads, except upon swelling over time in culture media. When used to encapsulate MIN6 cells, a beta cell line, Alg-PFC beads demonstrated enhanced cell proliferation over alginate control beads. These results indicate that Alg-PFC hydrogels retain some of the PFC's biological-relevant benefits, such as enhancement of mass transport and bioinertness, to enhance cellular viability within alginate three-dimensional hydrogel environments. We envision these functionalized hydrogels to be particularly useful in the encapsulation of cells with a high metabolic demand, such as pancreatic islets. Copyright © 2012 Wiley Periodicals, Inc.

  12. Logic-Based and Cellular Pharmacodynamic Modeling of Bortezomib Responses in U266 Human Myeloma Cells.

    Science.gov (United States)

    Chudasama, Vaishali L; Ovacik, Meric A; Abernethy, Darrell R; Mager, Donald E

    2015-09-01

    Systems models of biological networks show promise for informing drug target selection/qualification, identifying lead compounds and factors regulating disease progression, rationalizing combinatorial regimens, and explaining sources of intersubject variability and adverse drug reactions. However, most models of biological systems are qualitative and are not easily coupled with dynamical models of drug exposure-response relationships. In this proof-of-concept study, logic-based modeling of signal transduction pathways in U266 multiple myeloma (MM) cells is used to guide the development of a simple dynamical model linking bortezomib exposure to cellular outcomes. Bortezomib is a commonly used first-line agent in MM treatment; however, knowledge of the signal transduction pathways regulating bortezomib-mediated cell cytotoxicity is incomplete. A Boolean network model of 66 nodes was constructed that includes major survival and apoptotic pathways and was updated using responses to several chemical probes. Simulated responses to bortezomib were in good agreement with experimental data, and a reduction algorithm was used to identify key signaling proteins. Bortezomib-mediated apoptosis was not associated with suppression of nuclear factor κB (NFκB) protein inhibition in this cell line, which contradicts a major hypothesis of bortezomib pharmacodynamics. A pharmacodynamic model was developed that included three critical proteins (phospho-NFκB, BclxL, and cleaved poly (ADP ribose) polymerase). Model-fitted protein dynamics and cell proliferation profiles agreed with experimental data, and the model-predicted IC50 (3.5 nM) is comparable to the experimental value (1.5 nM). The cell-based pharmacodynamic model successfully links bortezomib exposure to MM cellular proliferation via protein dynamics, and this model may show utility in exploring bortezomib-based combination regimens. U.S. Government work not protected by U.S. copyright.

  13. Endoplasmic Reticulum–Mitochondrial Ca2+ Fluxes Underlying Cancer Cell Survival

    Directory of Open Access Journals (Sweden)

    Hristina Ivanova

    2017-05-01

    Full Text Available Calcium ions (Ca2+ are crucial, ubiquitous, intracellular second messengers required for functional mitochondrial metabolism during uncontrolled proliferation of cancer cells. The mitochondria and the endoplasmic reticulum (ER are connected via “mitochondria-associated ER membranes” (MAMs where ER–mitochondria Ca2+ transfer occurs, impacting the mitochondrial biology related to several aspects of cellular survival, autophagy, metabolism, cell death sensitivity, and metastasis, all cancer hallmarks. Cancer cells appear addicted to these constitutive ER–mitochondrial Ca2+ fluxes for their survival, since they drive the tricarboxylic acid cycle and the production of mitochondrial substrates needed for nucleoside synthesis and proper cell cycle progression. In addition to this, the mitochondrial Ca2+ uniporter and mitochondrial Ca2+ have been linked to hypoxia-inducible factor 1α signaling, enabling metastasis and invasion processes, but they can also contribute to cellular senescence induced by oncogenes and replication. Finally, proper ER–mitochondrial Ca2+ transfer seems to be a key event in the cell death response of cancer cells exposed to chemotherapeutics. In this review, we discuss the emerging role of ER–mitochondrial Ca2+ fluxes underlying these cancer-related features.

  14. Epigenetics and Cellular Metabolism

    Directory of Open Access Journals (Sweden)

    Wenyi Xu

    2016-01-01

    Full Text Available Living eukaryotic systems evolve delicate cellular mechanisms for responding to various environmental signals. Among them, epigenetic machinery (DNA methylation, histone modifications, microRNAs, etc. is the hub in transducing external stimuli into transcriptional response. Emerging evidence reveals the concept that epigenetic signatures are essential for the proper maintenance of cellular metabolism. On the other hand, the metabolite, a main environmental input, can also influence the processing of epigenetic memory. Here, we summarize the recent research progress in the epigenetic regulation of cellular metabolism and discuss how the dysfunction of epigenetic machineries influences the development of metabolic disorders such as diabetes and obesity; then, we focus on discussing the notion that manipulating metabolites, the fuel of cell metabolism, can function as a strategy for interfering epigenetic machinery and its related disease progression as well.

  15. Reversible effect of all-trans-retinoic acid on AML12 hepatocyte proliferation and cell cycle progression

    Science.gov (United States)

    The role of all-trans-retinoic acid (atRA) in the regulation of cellular proliferation and differentiation is well documented. Numerous studies have established the cancer preventive propertiesofatRAwhichfunctionstoregulate levels ofcellcycleproteinsessentialfortheGliS transition...

  16. Wireless Cellular Mobile Communications

    Directory of Open Access Journals (Sweden)

    V. Zalud

    2002-12-01

    Full Text Available In this article is briefly reviewed the history of wireless cellularmobile communications, examined the progress in current secondgeneration (2G cellular standards and discussed their migration to thethird generation (3G. The European 2G cellular standard GSM and itsevolution phases GPRS and EDGE are described somewhat in detail. Thethird generation standard UMTS taking up on GSM/GPRS core network andequipped with a new advanced access network on the basis of codedivision multiple access (CDMA is investigated too. A sketch of theperspective of mobile communication beyond 3G concludes this article.

  17. SIRT1 overexpression antagonizes cellular senescence with activated ERK/S6k1 signaling in human diploid fibroblasts.

    Directory of Open Access Journals (Sweden)

    Jing Huang

    Full Text Available Sir2, a NAD-dependent deacetylase, modulates lifespan in yeasts, worms and flies. The SIRT1, mammalian homologue of Sir2, regulates signaling for favoring survival in stress. But whether SIRT1 has the function to influence cell viability and senescence under non-stressed conditions in human diploid fibroblasts is far from unknown. Our data showed that enforced SIRT1 expression promoted cell proliferation and antagonized cellular senescence with the characteristic features of delayed Senescence-Associated beta-galactosidase (SA-beta-gal staining, reduced Senescence-Associated Heterochromatic Foci (SAHF formation and G1 phase arrest, increased cell growth rate and extended cellular lifespan in human fibroblasts, while dominant-negative SIRT1 allele (H363Y did not significantly affect cell growth and senescence but displayed a bit decreased lifespan. Western blot results showed that SIRT1 reduced the expression of p16(INK4A and promoted phosphorylation of Rb. Our data also exposed that overexpression of SIRT1 was accompanied by enhanced activation of ERK and S6K1 signaling. These effects were mimicked in both WI38 cells and 2BS cells by concentration-dependent resveratrol, a SIRT1 activator. It was noted that treatment of SIRT1-.transfected cells with Rapamycin, a mTOR inhibitor, reduced the phosphorylation of S6K1 and the expression of Id1, implying that SIRT1-induced phosphorylation of S6K1 may be partly for the decreased expression of p16(INK4A and promoted phosphorylation of Rb in 2BS. It was also observed that the expression of SIRT1 and phosphorylation of ERK and S6K1 was declined in senescent 2BS. These findings suggested that SIRT1-promoted cell proliferation and antagonized cellular senescence in human diploid fibroblasts may be, in part, via the activation of ERK/ S6K1 signaling.

  18. JPRS report. Proliferation issues

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-07-10

    This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical, and biological weapons, including delivery systems and the transfer of weapons-relevant technologies. Foreign Broadcast Information Service (FBIS) and Joint Publications Research Service (JPRS) publications contain political, military, economic, environmental, and sociological news, commentary, and other information, as well as scientific and technical data and reports. All information has been obtained from foreign radio and television broadcasts, news agency transmissions, newspapers, books, and periodicals. Items generally are processed from the first or best available sources. It should not be inferred that they have been disseminated only in the medium, in the language, or to the area indicated. Items from foreign language sources are translated; those from English-language sources are transcribed. Except for excluding certain diacritics, FBIS renders personal names and place-names in accordance with the romanization systems approved for U.S. Government publications by the U.S. Board of Geographic Names.

  19. JPRS report. Proliferation issues

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-03-13

    This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical, and biological weapons, including delivery systems and the transfer of weapons-relevant technologies. Foreign Broadcast Information Service (FBIS) and Joint Publications Research Service (JPRS) publications contain political, military, economic, environmental, and sociological news, commentary, and other information, as well as scientific and technical data and reports. All information has been obtained from foreign radio and television broadcasts. news agency transmissions, newspapers, books, and periodicals. Items generally are processed from the first or best available sources. It should not be inferred that they have been disseminated only in the medium, in the language, or to the area indicated. Items from foreign language sources are translated; those from English-language sources are transcribed. Except for excluding certain diacritics, FBIS renders personal names and place-names in accordance with the romanization systems approved for U.S. Government publications by the U.S. Board of Geographic Names.

  20. JPRS report. Proliferation issues

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-07-16

    This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical, and biological weapons, including delivery systems and the transfer of weapons-relevant technologies. Foreign Broadcast Information Service (FBIS) and Joint Publications Research Service (JPRS) publications contain political, military, economic, environmental, and sociological news, commentary, and other information, as well as scientific and technical data and reports. All information has been obtained from foreign radio and television broadcasts, news agency transmissions, newspapers, books, and periodicals. Items generally are processed from the first or best available sources. It should not be inferred that they have been disseminated only in the medium, in the language, or to the area indicated. Items from foreign language sources are translated; those from English-language sources are transcribed. Except for excluding certain diacritics, FBIS renders personal names and place-names in accordance with the romanization systems approved for U.S. Government publications by the U.S. Board of Geographic Names.

  1. JPRS report. Proliferation issues

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-02-21

    This report contains foreign media information on issues related to worldwide proliferation and transfer activities in nuclear, chemical, and biological weapons, including delivery systems and the transfer of weapons-relevant technologies. Foreign Broadcast Information Service (FBIS) and Joint Publications Research Service (JPRS) publications contain political, military, economic, environmental, and sociological news, commentary, and other information, as well as scientific and technical data and reports. All information has been obtained from foreign radio and television broadcasts, news agency transmissions, newspapers, books, and periodicals. Items generally are processed from the first or best available sources. It should not be inferred that they have been disseminated only in the medium, in the language, or to the area indicated. Items from foreign language sources are translated; those from English-language sources are transcribed. Except for excluding certain diacritics, FBIS renders personal names and place-names in accordance with the romanization systems approved for U.S. Government publications by the U.S. Board of Geographic Names.

  2. Niclosamide, an anti-helminthic molecule, downregulates the retroviral oncoprotein Tax and pro-survival Bcl-2 proteins in HTLV-1-transformed T lymphocytes.

    Science.gov (United States)

    Xiang, Di; Yuan, Yunsheng; Chen, Li; Liu, Xin; Belani, Chandra; Cheng, Hua

    2015-08-14

    Adult T cell leukemia and lymphoma (ATL) is a highly aggressive form of hematological malignancy and is caused by chronic infection of human T cell leukemia virus type 1 (HTLV-1). The viral genome encodes an oncogenic protein, Tax, which plays a key role in transactivating viral gene transcription and in deregulating cellular oncogenic signaling to promote survival, proliferation and transformation of virally infected T cells. Hence, Tax is a desirable therapeutic target, particularly at early stage of HTLV-1-mediated oncogenesis. We here show that niclosamide, an anti-helminthic molecule, induced apoptosis of HTLV-1-transformed T cells. Niclosamide facilitated degradation of the Tax protein in proteasome. Consistent with niclosamide-mediated Tax degradation, this compound inhibited activities of MAPK/ERK1/2 and IκB kinases. In addition, niclosamide downregulated Stat3 and pro-survival Bcl-2 family members such as Mcl-1 and repressed the viral gene transcription of HTLV-1 through induction of Tax degradation. Since Tax, Stat3 and Mcl-1 are crucial molecules for promoting survival and growth of HTLV-1-transformed T cells, our findings demonstrate a novel mechanism of niclosamide in inducing Tax degradation and downregulating various cellular pro-survival molecules, thereby promoting apoptosis of HTLV-1-associated leukemia cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Aryl hydrocarbon receptor-dependent regulation of miR-196a expression controls lung fibroblast apoptosis but not proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Hecht, Emelia [Department of Medicine, McGill University, Montreal, Quebec (Canada); Zago, Michela [Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Sarill, Miles [Department of Medicine, McGill University, Montreal, Quebec (Canada); Rico de Souza, Angela [Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Gomez, Alvin; Matthews, Jason [Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON (Canada); Hamid, Qutayba; Eidelman, David H. [Department of Medicine, McGill University, Montreal, Quebec (Canada); Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Baglole, Carolyn J., E-mail: Carolyn.baglole@McGill.ca [Department of Medicine, McGill University, Montreal, Quebec (Canada); Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada)

    2014-11-01

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor implicated in the regulation of apoptosis and proliferation. Although activation of the AhR by xenobiotics such as dioxin inhibits the cell cycle and control apoptosis, paradoxically, AhR expression also promotes cell proliferation and survival independent of exogenous ligands. The microRNA (miRNA) miR-196a has also emerged as a regulator of proliferation and apoptosis but a relationship between the AhR and miR-196a is not known. Therefore, we hypothesized that AhR-dependent regulation of endogenous miR-196a expression would promote cell survival and proliferation. Utilizing lung fibroblasts from AhR deficient (AhR{sup −/−}) and wild-type (AhR{sup +/+}) mice, we show that there is ligand-independent regulation of miRNA, including low miR-196a in AhR{sup −/−} cells. Validation by qRT-PCR revealed a significant decrease in basal expression of miR-196a in AhR{sup −/−} compared to AhR{sup +/+} cells. Exposure to AhR agonists benzo[a]pyrene (B[a]P) and FICZ as well as AhR antagonist CH-223191 decreased miR-196a expression in AhR{sup +/+} fibroblasts concomitant with decreased AhR protein levels. There was increased proliferation only in AhR{sup +/+} lung fibroblasts in response to serum, corresponding to a decrease in p27{sup KIP1} protein, a cyclin-dependent kinase inhibitor. Increasing the cellular levels of miR-196a had no effect on proliferation or expression of p27{sup KIP1} in AhR{sup −/−} fibroblasts but attenuated cigarette smoke-induced apoptosis. This study provides the first evidence that AhR expression is essential for the physiological regulation of cellular miRNA levels- including miR-196a. Future experiments designed to elucidate the functional relationship between the AhR and miR-196a may delineate additional novel ligand-independent roles for the AhR. - Highlights: • The AhR controls proliferation and apoptosis in lung cells. • The AhR regulates the

  4. Regulation of germline stem cell proliferation downstream of nutrient sensing

    Directory of Open Access Journals (Sweden)

    Roy Richard

    2006-12-01

    Full Text Available Abstract Stem cells have recently attracted significant attention largely due to their potential therapeutic properties, but also because of their role in tumorigenesis and their resemblance, in many aspects, to cancerous cells. Understanding how stem cells are regulated, namely with respect to the control of their proliferation and differentiation within a functional organism, is thus primordial to safely profit from their therapeutic benefits. Here, we review recent advances in the understanding of germline stem cell proliferation control by factors that respond to the nutritional status and/or insulin signaling, through studies performed in C. elegans and Drosophila. Together, these data uncover some shared fundamental features that underlie the central control of cellular proliferation within a target stem cell population in an organism. These features may indeed be conserved in higher organisms and may apply to various other stem cell populations.

  5. Chemical Methods to Induce Beta-Cell Proliferation

    Directory of Open Access Journals (Sweden)

    Amedeo Vetere

    2012-01-01

    Full Text Available Pancreatic beta-cell regeneration, for example, by inducing proliferation, remains an important goal in developing effective treatments for diabetes. However, beta cells have mainly been considered quiescent. This “static” view has recently been challenged by observations of relevant physiological conditions in which metabolic stress is compensated by an increase in beta-cell mass. Understanding the molecular mechanisms underlining these process could open the possibility of developing novel small molecules to increase beta-cell mass. Several cellular cell-cycle and signaling proteins provide attractive targets for high throughput screening, and recent advances in cell culture have enabled phenotypic screening for small molecule-induced beta-cell proliferation. We present here an overview of the current trends involving small-molecule approaches to induce beta-cell regeneration by proliferation.

  6. Androgen receptor drives cellular senescence.

    Directory of Open Access Journals (Sweden)

    Yelena Mirochnik

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

  7. B cell activating factor (BAFF) and a proliferation inducing ligand (APRIL) mediate CD40-independent help by memory CD4 T cells.

    Science.gov (United States)

    Gorbacheva, V; Ayasoufi, K; Fan, R; Baldwin, W M; Valujskikh, A

    2015-02-01

    Donor-reactive memory T cells undermine organ transplant survival and are poorly controlled by immunosuppression or costimulatory blockade. Memory CD4 T cells provide CD40-independent help for the generation of donor-reactive effector CD8 T cells and alloantibodies (alloAbs) that rapidly mediate allograft rejection. The goal of this study was to investigate the role of B cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) in alloresponses driven by memory CD4 T cells. The short-term neutralization of BAFF alone or BAFF plus APRIL synergized with anti-CD154 mAb to prolong heart allograft survival in recipients containing donor-reactive memory CD4 T cells. The prolongation was associated with reduction in antidonor alloAb responses and with inhibited reactivation and helper functions of memory CD4 T cells. Additional depletion of CD8 T cells did not enhance the prolonged allograft survival suggesting that donor-reactive alloAbs mediate late graft rejection in these recipients. This is the first report that targeting the BAFF cytokine network inhibits both humoral and cellular immune responses induced by memory CD4 T cells. Our results suggest that reagents neutralizing BAFF and APRIL may be used to enhance the efficacy of CD40/CD154 costimulatory blockade and improve allograft survival in T cell-sensitized recipients. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.

  8. Click Chemistry for Analysis of Cell Proliferation in Flow Cytometry.

    Science.gov (United States)

    Clarke, Scott T; Calderon, Veronica; Bradford, Jolene A

    2017-10-02

    The measurement of cellular proliferation is fundamental to the assessment of cellular health, genotoxicity, and the evaluation of drug efficacy. Labeling, detection, and quantification of cells in the synthesis phase of cell cycle progression are not only important for characterizing basic biology, but also in defining cellular responses to drug treatments. Changes in DNA replication during S-phase can provide valuable insights into mechanisms of cell growth, cell cycle kinetics, and cytotoxicity. A common method for detection of cell proliferation is the incorporation of a thymidine analog during DNA synthesis. This chapter presents a pulse labeling method using the thymidine analog, 5-ethynyl-2'-deoxyuridine (EdU), with subsequent detection by click chemistry. EdU detection using click chemistry is bio-orthogonal to most living systems and does not non-specifically label other biomolecules. Live cells are first pulsed with EdU. After antibody labeling cell surface markers, fixation, and permeabilization, the incorporated EdU is covalently labeled using click chemistry thereby identifying proliferating cells. Improvements in click chemistry allow for labeling in the presence of fluorescent proteins and phycobiliproteins without quenching due to copper. Measuring DNA replication during cell cycle progression has cell health applications in flow cytometry, fluorescence microscopy, and high content imaging. This protocol has been developed and optimized for research use only and is not suitable for use in diagnostic procedures. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  9. Hydrogen sulfide (H{sub 2}S)/cystathionine γ-lyase (CSE) pathway contributes to the proliferation of hepatoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Yan; Ye, Shuang; Yuan, Dexiao; Zhang, Jianghong; Bai, Yang; Shao, Chunlin, E-mail: clshao@shmu.edu.cn

    2014-05-15

    Highlights: • Inhibition of H{sub 2}S/CSE pathway strongly stimulates cellular apoptosis. • Inhibition of H{sub 2}S/CSE pathway suppresses cell growth by blocking EGFR pathway. • H{sub 2}S/CSE pathway is critical for maintaining the proliferation of hepatoma cells. - Abstract: Hydrogen sulfide (H{sub 2}S)/cystathionine γ-lyase (CSE) pathway has been demonstrated to play vital roles in physiology and pathophysiology. However, its role in tumor cell proliferation remains largely unclear. Here we found that CSE over-expressed in hepatoma HepG2 and PLC/PRF/5 cells. Inhibition of endogenous H{sub 2}S/CSE pathway drastically decreased the proliferation of HepG2 and PLC/PRF/5 cells, and it also enhanced ROS production and mitochondrial disruption, pronounced DNA damage and increased apoptosis. Moreover, this increase of apoptosis was associated with the activation of p53 and p21 accompanied by a decreased ratio of Bcl-2/Bax and up-regulation of phosphorylated c-Jun N-terminal kinase (JNK) and caspase-3 activity. In addition, the negative regulation of cell proliferation by inhibition of H{sub 2}S/CSE system correlated with the blockage of cell mitogenic and survival signal transduction of epidermal growth factor receptor (EGFR) via down-regulating the extracellular-signal-regulated kinase 1/2 (ERK1/2) activation. These results demonstrate that H{sub 2}S/CSE and its downstream pathway contribute to the proliferation of hepatoma cells, and inhibition of this pathway strongly suppress the excessive growth of hepatoma cells by stimulating mitochondrial apoptosis and suppressing cell growth signal transduction.

  10. Vitrification preserves proliferation capacity in human spermatogonia.

    Science.gov (United States)

    Poels, Jonathan; Van Langendonckt, Anne; Many, Marie-Christine; Wese, François-Xavier; Wyns, Christine

    2013-03-01

    Does vitrification of human immature testicular tissue (ITT) have potential benefits for future fertility preservation? Does vitrification of human ITT have potential benefits in an in vivo murine xenotransplantation model? Vitrification is able to maintain proliferation capacity in spermatogonial cells after 6 months of xenografting. Controlled slow-freezing is the procedure currently applied for ITT cryobanking in clinical practice. Vitrification has been proposed as a promising technique for long-term storage of ITT, with a view to preserving spermatogonial stem cells (SSCs) for future fertility restoration in young boys suffering from cancer. After vitrification of ITT, in vitro survival of SSCs was demonstrated, but their functionality was not evaluated. Ten ITT pieces issuing from 10 patients aged 2-12 years were used. Fragments of fresh tissue (serving as controls) and fresh, frozen-thawed and vitrified-warmed testicular pieces xenografted to the scrotum of nude mice for 6 months were compared. Upon graft removal, histological and immunohistochemical analyses were performed to evaluate spermatogonia (SG) (MAGE-A4), intratubular proliferation (Ki67), proliferating SG and Leydig cells (3β-HSD). The entire piece of grafted tissue was assessed in each case. Seminiferous tubules showed good integrity after cryopreservation and xenografting for 6 months in all three groups. Survival of SG and their ability to proliferate was observed by immunohistochemistry in all grafted groups. SG were able to initiate spermatogenesis, but blockage at the pachytene stage was observed. The recovery rate of SG was 3.4 ± 3.8, 4.1 ± 7.3 and 7.3 ± 6.3%, respectively, for fresh, slow-frozen and vitrified-warmed tissue after 6 months of xenografting. The study is limited by the low availability of ITT samples of human origin. The mouse xenotransplantation model needs to be refined to study human spermatogenesis. The findings of the present study have potential implications for

  11. Contribution of mesenchymal proliferation in tooth root morphogenesis.

    Science.gov (United States)

    Sohn, W-J; Choi, M-A; Yamamoto, H; Lee, S; Lee, Y; Jung, J-K; Jin, M-U; An, C-H; Jung, H-S; Suh, J-Y; Shin, H-I; Kim, J-Y

    2014-01-01

    In mouse tooth development, the roots of the first lower molar develop after crown formation to form 2 cylindrical roots by post-natal day 5. This study compared the morphogenesis and cellular events of the mesial-root-forming (MRF) and bifurcation-forming (BF) regions, located in the mesial and center of the first lower molar, to better define the developmental mechanisms involved in multi-rooted tooth formation. We found that the mesenchyme in the MRF showed relatively higher proliferation than the bifurcation region. This suggested that spatially regulated mesenchymal proliferation is required for creating cylindrical root structure. The mechanism may involve the mesenchyme forming a physical barrier to epithelial invagination of Hertwig's epithelial root sheath. To test these ideas, we cultured roots in the presence of pharmacological inhibitors of microtubule and actin polymerization, nocodazole and cytochalasin-D. Cytochalasin D also inhibits proliferation in epithelium and mesenchyme. Both drugs resulted in altered morphological changes in the tooth root structures. In particular, the nocodazole- and cytochalasin-D-treated specimens showed a loss of root diameter and formation of a single-root, respectively. Immunolocalization and three-dimensional reconstruction results confirmed these mesenchymal cellular events, with higher proliferation in MRF in multi-rooted tooth formation.

  12. The New Cellular Immunology

    Science.gov (United States)

    Claman, Henry N.

    1973-01-01

    Discusses the nature of the immune response and traces many of the discoveries that have led to the present state of knowledge in immunology. The new cellular immunology is directing its efforts toward improving health by proper manipulation of the immune mechanisms of the body. (JR)

  13. Identification of Predictive Gene Markers for Multipotent Stromal Cell Proliferation.

    Science.gov (United States)

    Bellayr, Ian H; Marklein, Ross A; Lo Surdo, Jessica L; Bauer, Steven R; Puri, Raj K

    2016-06-01

    Multipotent stromal cells (MSCs) are known for their distinctive ability to differentiate into different cell lineages, such as adipocytes, chondrocytes, and osteocytes. They can be isolated from numerous tissue sources, including bone marrow, adipose tissue, skeletal muscle, and others. Because of their differentiation potential and secretion of growth factors, MSCs are believed to have an inherent quality of regeneration and immune suppression. Cellular expansion is necessary to obtain sufficient numbers for use; however, MSCs exhibit a reduced capacity for proliferation and differentiation after several rounds of passaging. In this study, gene markers of MSC proliferation were identified and evaluated for their ability to predict proliferative quality. Microarray data of human bone marrow-derived MSCs were correlated with two proliferation assays. A collection of 24 genes were observed to significantly correlate with both proliferation assays (|r| >0.70) for eight MSC lines at multiple passages. These 24 identified genes were then confirmed using an additional set of MSCs from eight new donors using reverse transcription quantitative polymerase chain reaction (RT-qPCR). The proliferative potential of the second set of MSCs was measured for each donor/passage for confluency fraction, fraction of EdU+ cells, and population doubling time. The second set of MSCs exhibited a greater proliferative potential at passage 4 in comparison to passage 8, which was distinguishable by 15 genes; however, only seven of the genes (BIRC5, CCNA2, CDC20, CDK1, PBK, PLK1, and SPC25) demonstrated significant correlation with MSC proliferation regardless of passage. Our analyses revealed that correlation between gene expression and proliferation was consistently reduced with the inclusion of non-MSC cell lines; therefore, this set of seven genes may be more strongly associated with MSC proliferative quality. Our results pave the way to determine the quality of an MSC population for a

  14. PI3K/AKT and ERK regulate retinoic acid-induced neuroblastoma cellular differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Jingbo [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Paul, Pritha; Lee, Sora [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Qiao, Lan; Josifi, Erlena; Tiao, Joshua R. [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Chung, Dai H., E-mail: dai.chung@vanderbilt.edu [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer Retinoic acid (RA) induces neuroblastoma cells differentiation, which is accompanied by G0/G1 cell cycle arrest. Black-Right-Pointing-Pointer RA resulted in neuroblastoma cell survival and inhibition of DNA fragmentation; this is regulated by PI3K pathway. Black-Right-Pointing-Pointer RA activates PI3K and ERK1/2 pathway; PI3K pathway mediates RA-induced neuroblastoma cell differentiation. Black-Right-Pointing-Pointer Upregulation of p21 is necessary for RA-induced neuroblastoma cell differentiation. -- Abstract: Neuroblastoma, the most common extra-cranial solid tumor in infants and children, is characterized by a high rate of spontaneous remissions in infancy. Retinoic acid (RA) has been known to induce neuroblastoma differentiation; however, the molecular mechanisms and signaling pathways that are responsible for RA-mediated neuroblastoma cell differentiation remain unclear. Here, we sought to determine the cell signaling processes involved in RA-induced cellular differentiation. Upon RA administration, human neuroblastoma cell lines, SK-N-SH and BE(2)-C, demonstrated neurite extensions, which is an indicator of neuronal cell differentiation. Moreover, cell cycle arrest occurred in G1/G0 phase. The protein levels of cyclin-dependent kinase inhibitors, p21 and p27{sup Kip}, which inhibit cell proliferation by blocking cell cycle progression at G1/S phase, increased after RA treatment. Interestingly, RA promoted cell survival during the differentiation process, hence suggesting a potential mechanism for neuroblastoma resistance to RA therapy. Importantly, we found that the PI3K/AKT pathway is required for RA-induced neuroblastoma cell differentiation. Our results elucidated the molecular mechanism of RA-induced neuroblastoma cellular differentiation, which may be important for developing novel therapeutic strategy against poorly differentiated neuroblastoma.

  15. The role of nuclear factor κB in the cellular response to different radiation qualities

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Kristina

    2013-04-11

    line was characterized concerning proliferation, cell cycle progression and gene expression. Additionally, the effects of the RelA knockdown on cell cycle progression, cellular survival and gene expression after exposure to low and high LET radiation were investigated. It was shown that activation of NF-κB depends on radiation quality and quantity. Experiments with chemical inhibitors revealed that NF-κB activation by ionizing radiation is strictly ATM dependent and degradation of the NF-κB inhibitor IκB by the proteasome is essential for both the classical and genotoxic stress-induced NF-κB pathway. Absence of NF-κB dimers containing RelA resulted in a prolonged lag-phase but did not affect cell cycle progression significantly in untreated cells. After irradiation, a dose and radiation quality dependent arrest in the G2 phase of the cell cycle occurred and also upon downregulation of RelA expression. RelA knockdown resulted in higher sensitivity of HEK cells to the killing effect of X-irradiation. In contrast, RelA knockdown did not further reduce the cellular survival after heavy ion exposure. Further, NF-κB target genes were not inducible in the RelA knockdown cell line. NF-κB-dependent gene expression rely on radiation dose and LET. Chemokine expression (e.g. CXCL1, 2, 8 and 10) was induced in a proportional manner to radiation quality and quantity, emphasizing the role of NF-κB in the bystander effect. These NF-κB regulated genes are interesting targets for countermeasure development against the effects of space radiation.

  16. Inhibition of glycogen synthase kinase-3 enhances the differentiation and reduces the proliferation of adult human olfactory epithelium neural precursors

    Energy Technology Data Exchange (ETDEWEB)

    Manceur, Aziza P. [Institute of Biomaterials and Biomedical Engineering (IBBME), University of Toronto, Toronto, Ontario (Canada); Donnelly Centre, University of Toronto, Toronto, Ontario (Canada); Tseng, Michael [Laboratory of Cellular and Molecular Pathophysiology, Centre for Addiction and Mental Health (CAMH), University of Toronto, Toronto, Ontario (Canada); Department of Psychiatry, University of Toronto, Toronto, ON (Canada); Institute of Medical Science, University of Toronto, Toronto, ON (Canada); Holowacz, Tamara [Donnelly Centre, University of Toronto, Toronto, Ontario (Canada); Witterick, Ian [Institute of Medical Science, University of Toronto, Toronto, ON (Canada); Department of Otolaryngology, Head and Neck Surgery, University of Toronto, ON (Canada); Weksberg, Rosanna [Institute of Medical Science, University of Toronto, Toronto, ON (Canada); The Hospital for Sick Children, Research Institute, Program in Genetics and Genomic Biology, Toronto, Ontario Canada (Canada); McCurdy, Richard D. [The Hospital for Sick Children, Research Institute, Program in Genetics and Genomic Biology, Toronto, Ontario Canada (Canada); Warsh, Jerry J. [Laboratory of Cellular and Molecular Pathophysiology, Centre for Addiction and Mental Health (CAMH), University of Toronto, Toronto, Ontario (Canada); Department of Psychiatry, University of Toronto, Toronto, ON (Canada); Institute of Medical Science, University of Toronto, Toronto, ON (Canada); Audet, Julie, E-mail: julie.audet@utoronto.ca [Institute of Biomaterials and Biomedical Engineering (IBBME), University of Toronto, Toronto, Ontario (Canada); Donnelly Centre, University of Toronto, Toronto, Ontario (Canada)

    2011-09-10

    The olfactory epithelium (OE) contains neural precursor cells which can be easily harvested from a minimally invasive nasal biopsy, making them a valuable cell source to study human neural cell lineages in health and disease. Glycogen synthase kinase-3 (GSK-3) has been implicated in the etiology and treatment of neuropsychiatric disorders and also in the regulation of murine neural precursor cell fate in vitro and in vivo. In this study, we examined the impact of decreased GSK-3 activity on the fate of adult human OE neural precursors in vitro. GSK-3 inhibition was achieved using ATP-competitive (6-bromoindirubin-3'-oxime and CHIR99021) or substrate-competitive (TAT-eIF2B) inhibitors to eliminate potential confounding effects on cell fate due to off-target kinase inhibition. GSK-3 inhibitors decreased the number of neural precursor cells in OE cell cultures through a reduction in proliferation. Decreased proliferation was not associated with a reduction in cell survival but was accompanied by a reduction in nestin expression and a substantial increase in the expression of the neuronal differentiation markers MAP1B and neurofilament (NF-M) after 10 days in culture. Taken together, these results suggest that GSK-3 inhibition promotes the early stages of neuronal differentiation in cultures of adult human neural precursors and provide insights into the mechanisms by which alterations in GSK-3 signaling affect adult human neurogenesis, a cellular process strongly suspected to play a role in the etiology of neuropsychiatric disorders.

  17. Increased HAGLR expression promotes non-small cell lung cancer proliferation and invasion via enhanced de novo lipogenesis.

    Science.gov (United States)

    Lu, Chunwei; Ma, Jun; Cai, Dingfang

    2017-04-01

    Lung cancers are broadly classified into small cell lung cancer and non-small cell lung cancer, with non-small cell lung cancer one of the leading causes of cancer-associated deaths worldwide. Presently, the mechanisms underlying lung tumorigenesis remain incompletely understood. Accumulating evidence indicates that abnormal expression of long non-coding RNAs is associated with tumorigenesis in multiple cancers, including lung cancer. HAGLR messenger RNA of non-small cell lung cancer tissues was significantly higher. Moreover, high levels of HAGLR expression were associated with non-small cell lung cancer tumor lymph node metastasis status, stage, and poor overall survival. Inhibition of HAGLR in non-small cell lung cancer cells suppressed cell proliferation and invasion. RNA interference-mediated downregulation of HAGLR also decreased levels of fatty acid synthase, with fatty acid synthase levels positively correlated with HAGLR expression in non-small cell lung cancer specimens. In addition, the cellular free fatty acid content of cancer cells was decreased following HAGLR knockdown. HAGLR depletion significantly inhibited the growth of non-small cell lung cancer cells in vivo. Furthermore, the expression levels of p21 and matrix metallopeptidase-9 (MMP-9) were dysregulated when HAGLR expression was suppressed. Our results suggest that HAGLR is an important regulator of non-small cell lung cancer cell proliferation and invasion, perhaps by regulating fatty acid synthase. Therefore, targeting HAGLR may be a possible therapeutic strategy for non-small cell lung cancer.

  18. Spheroid Culture of Head and Neck Cancer Cells Reveals an Important Role of EGFR Signalling in Anchorage Independent Survival.

    Science.gov (United States)

    Braunholz, Diana; Saki, Mohammad; Niehr, Franziska; Öztürk, Merve; Borràs Puértolas, Berta; Konschak, Robert; Budach, Volker; Tinhofer, Ingeborg

    2016-01-01

    In solid tumours millions of cells are shed into the blood circulation each day. Only a subset of these circulating tumour cells (CTCs) survive, many of them presumable because of their potential to form multi-cellular clusters also named spheroids. Tumour cells within these spheroids are protected from anoikis, which allows them to metastasize to distant organs or re-seed at the primary site. We used spheroid cultures of head and neck squamous cell carcinoma (HNSCC) cell lines as a model for such CTC clusters for determining the role of the epidermal growth factor receptor (EGFR) in cluster formation ability and cell survival after detachment from the extra-cellular matrix. The HNSCC cell lines FaDu, SCC-9 and UT-SCC-9 (UT-SCC-9P) as well as its cetuximab (CTX)-resistant sub-clone (UT-SCC-9R) were forced to grow in an anchorage-independent manner by coating culture dishes with the anti-adhesive polymer poly-2-hydroxyethylmethacrylate (poly-HEMA). The extent of apoptosis, clonogenic survival and EGFR signalling under such culture conditions was evaluated. The potential of spheroid formation in suspension culture was found to be positively correlated with the proliferation rate of HNSCC cell lines as well as their basal EGFR expression levels. CTX and gefitinib blocked, whereas the addition of EGFR ligands promoted anchorage-independent cell survival and spheroid formation. Increased spheroid formation and growth were associated with persistent activation of EGFR and its downstream signalling component (MAPK/ERK). Importantly, HNSCC cells derived from spheroid cultures retained their clonogenic potential in the absence of cell-matrix contact. Addition of CTX under these conditions strongly inhibited colony formation in CTX-sensitive cell lines but not their resistant subclones. Altogether, EGFR activation was identified as crucial factor for anchorage-independent survival of HNSCC cells. Targeting EGFR in CTC cluster formation might represent an attractive anti

  19. Survival and Adaptation of the Thermophilic Species Geobacillus thermantarcticus in Simulated Spatial Conditions

    Science.gov (United States)

    Di Donato, Paola; Romano, Ida; Mastascusa, Vincenza; Poli, Annarita; Orlando, Pierangelo; Pugliese, Mariagabriella; Nicolaus, Barbara

    2017-06-01

    Astrobiology studies the origin and evolution of life on Earth and in the universe. According to the panspermia theory, life on Earth could have emerged from bacterial species transported by meteorites, that were able to adapt and proliferate on our planet. Therefore, the study of extremophiles, i.e. bacterial species able to live in extreme terrestrial environments, can be relevant to Astrobiology studies. In this work we described the ability of the thermophilic species Geobacillus thermantarcticus to survive after exposition to simulated spatial conditions including temperature's variation, desiccation, X-rays and UVC irradiation. The response to the exposition to the space conditions was assessed at a molecular level by studying the changes in the morphology, the lipid and protein patterns, the nucleic acids. G. thermantarcticus survived to the exposition to all the stressing conditions examined, since it was able to restart cellular growth in comparable levels to control experiments carried out in the optimal growth conditions. Survival was elicited by changing proteins and lipids distribution, and by protecting the DNA's integrity.

  20. Transspinal direct current stimulation modulates migration and proliferation of adult newly born spinal cells in mice.

    Science.gov (United States)

    Samaddar, Sreyashi; Vazquez, Kizzy; Ponkia, Dipen; Toruno, Pedro; Sahbani, Karim; Begum, Sultana; Abouelela, Ahmed; Mekhael, Wagdy; Ahmed, Zaghloul

    2017-02-01

    Direct current electrical fields have been shown to be a major factor in the regulation of cell proliferation, differentiation, migration, and survival, as well as in the maturation of dividing cells during development. During adulthood, spinal cord cells are continuously produced in both animals and humans, and they hold great potential for neural restoration following spinal cord injury. While the effects of direct current electrical fields on adult-born spinal cells cultured ex vivo have recently been reported, the effects of direct current electrical fields on adult-born spinal cells in vivo have not been characterized. Here, we provide convincing findings that a therapeutic form of transspinal direct current stimulation (tsDCS) affects the migration and proliferation of adult-born spinal cells in mice. Specifically, cathodal tsDCS attracted the adult-born spinal cells, while anodal tsDCS repulsed them. In addition, both tsDCS polarities caused a significant increase in cell number. Regarding the potential mechanisms involved, both cathodal and anodal tsDCS caused significant increases in expression of brain-derived neurotrophic factor, while expression of nerve growth factor increased and decreased, respectively. In the spinal cord, both anodal and cathodal tsDCS increased blood flow. Since blood flow and angiogenesis are associated with the proliferation of neural stem cells, increased blood flow may represent a major factor in the modulation of newly born spinal cells by tsDCS. Consequently, we propose that the method and novel findings presented in the current study have the potential to facilitate cellular, molecular, and/or bioengineering strategies to repair injured spinal cords. NEW & NOTEWORTHY Our results indicate that transspinal direct current stimulation (tsDCS) affects the migratory pattern and proliferation of adult newly born spinal cells, a cell population which has been implicated in learning and memory. In addition, our results suggest a

  1. Cellular intrinsic mechanism affecting the outcome of AML treated with Ara-C in a syngeneic mouse model.

    Directory of Open Access Journals (Sweden)

    Wenjun Zhao

    Full Text Available The mechanisms underlying acute myeloid leukemia (AML treatment failure are not clear. Here, we established a mouse model of AML by syngeneic transplantation of BXH-2 derived myeloid leukemic cells and developed an efficacious Ara-C-based regimen for treatment of these mice. We proved that leukemic cell load was correlated with survival. We also demonstrated that the susceptibility of leukemia cells to Ara-C could significantly affect the survival. To examine the molecular alterations in cells with different sensitivity, genome-wide expression of the leukemic cells was profiled, revealing that overall 366 and 212 genes became upregulated or downregulated, respectively, in the resistant cells. Many of these genes are involved in the regulation of cell cycle, cellular proliferation, and apoptosis. Some of them were further validated by quantitative PCR. Interestingly, the Ara-C resistant cells retained the sensitivity to ABT-737, an inhibitor of anti-apoptosis proteins, and treatment with ABT-737 prolonged the life span of mice engrafted with resistant cells. These results suggest that leukemic load and intrinsic cellular resistance can affect the outcome of AML treated with Ara-C. Incorporation of apoptosis inhibitors, such as ABT-737, into traditional cytotoxic regimens merits consideration for the treatment of AML in a subset of patients with resistance to Ara-C. This work provided direct in vivo evidence that leukemic load and intrinsic cellular resistance can affect the outcome of AML treated with Ara-C, suggesting that incorporation of apoptosis inhibitors into traditional cytotoxic regimens merits consideration for the treatment of AML in a subset of patients with resistance to Ara-C.

  2. Delineation of the HPV11E6 and HPV18E6 Pathways in Initiating Cellular Transformation

    Directory of Open Access Journals (Sweden)

    Lamech M. Mwapagha

    2017-11-01

    Full Text Available Although high-risk human papillomaviruses (HPVs are the major risk factors for cervical cancer they have been associated with several other cancers, such as head and neck and oral cancers. Since integration of low-risk HPV11 DNA has been demonstrated in esophageal tumor genomes, this study compared the effects of low-risk HPV11E6 and high-risk HPV18E6 on cellular gene expression. The HPV11E6 and HPV18E6 genes were cloned into an adenoviral vector and expressed in human keratinocytes (HaCaT in order to investigate early events and to eliminate possible artifacts introduced by selective survival of fast growing cells in stable transfection experiments. HPV11E6 had very little effect on p21 and p53 gene expression, while HPV18E6 resulted in a marked reduction in both these proteins. Both HPV11E6 and HPV18E6 enabled growth of colonies in soft agar, but the level of colony formation was higher in HPV18E6 infected cells. DNA microarray analysis identified significantly differentially regulated genes involved in the cellular transformation signaling pathways. These findings suggest that HPV11E6 and HPV18E6 are important in initiating cellular transformation via deregulation of signaling pathways such as PI3K/AKT and pathways that are directly involved in DNA damage repair, cell survival, and cell proliferation. This study shows that the low-risk HPV11E6 may have similar effects as the high-risk HPV18E6 during the initial stages of infection, but at a much reduced level.

  3. Molecular and Cellular Signaling

    CERN Document Server

    Beckerman, Martin

    2005-01-01

    A small number of signaling pathways, no more than a dozen or so, form a control layer that is responsible for all signaling in and between cells of the human body. The signaling proteins belonging to the control layer determine what kinds of cells are made during development and how they function during adult life. Malfunctions in the proteins belonging to the control layer are responsible for a host of human diseases ranging from neurological disorders to cancers. Most drugs target components in the control layer, and difficulties in drug design are intimately related to the architecture of the control layer. Molecular and Cellular Signaling provides an introduction to molecular and cellular signaling in biological systems with an emphasis on the underlying physical principles. The text is aimed at upper-level undergraduates, graduate students and individuals in medicine and pharmacology interested in broadening their understanding of how cells regulate and coordinate their core activities and how diseases ...

  4. Cellularized Bilayer Pullulan-Gelatin Hydrogel for Skin Regeneration.

    Science.gov (United States)

    Nicholas, Mathew N; Jeschke, Marc G; Amini-Nik, Saeid

    2016-05-01

    Skin substitutes significantly reduce the morbidity and mortality of patients with burn injuries and chronic wounds. However, current skin substitutes have disadvantages related to high costs and inadequate skin regeneration due to highly inflammatory wounds. Thus, new skin substitutes are needed. By combining two polymers, pullulan, an inexpensive polysaccharide with antioxidant properties, and gelatin, a derivative of collagen with high water absorbency, we created a novel inexpensive hydrogel-named PG-1 for "pullulan-gelatin first generation hydrogel"-suitable for skin substitutes. After incorporating human fibroblasts and keratinocytes onto PG-1 using centrifugation over 5 days, we created a cellularized bilayer skin substitute. Cellularized PG-1 was compared to acellular PG-1 and no hydrogel (control) in vivo in a mouse excisional skin biopsy model using newly developed dome inserts to house the skin substitutes and prevent mouse skin contraction during wound healing. PG-1 had an average pore size of 61.69 μm with an ideal elastic modulus, swelling behavior, and biodegradability for use as a hydrogel for skin substitutes. Excellent skin cell viability, proliferation, differentiation, and morphology were visualized through live/dead assays, 5-bromo-2'-deoxyuridine proliferation assays, and confocal microscopy. Trichrome and immunohistochemical staining of excisional wounds treated with the cellularized skin substitute revealed thicker newly formed skin with a higher proportion of actively proliferating cells and incorporation of human cells compared to acellular PG-1 or control. Excisional wounds treated with acellular or cellularized hydrogels showed significantly less macrophage infiltration and increased angiogenesis 14 days post skin biopsy compared to control. These results show that PG-1 has ideal mechanical characteristics and allows ideal cellular characteristics. In vivo evidence suggests that cellularized PG-1 promotes skin regeneration and may

  5. Pulsed feedback defers cellular differentiation.

    Directory of Open Access Journals (Sweden)

    Joe H Levine

    2012-01-01

    Full Text Available Environmental signals induce diverse cellular differentiation programs. In certain systems, cells defer differentiation for extended time periods after the signal appears, proliferating through multiple rounds of cell division before committing to a new fate. How can cells set a deferral time much longer than the cell cycle? Here we study Bacillus subtilis cells that respond to sudden nutrient limitation with multiple rounds of growth and division before differentiating into spores. A well-characterized genetic circuit controls the concentration and phosphorylation of the master regulator Spo0A, which rises to a critical concentration to initiate sporulation. However, it remains unclear how this circuit enables cells to defer sporulation for multiple cell cycles. Using quantitative time-lapse fluorescence microscopy of Spo0A dynamics in individual cells, we observed pulses of Spo0A phosphorylation at a characteristic cell cycle phase. Pulse amplitudes grew systematically and cell-autonomously over multiple cell cycles leading up to sporulation. This pulse growth required a key positive feedback loop involving the sporulation kinases, without which the deferral of sporulation became ultrasensitive to kinase expression. Thus, deferral is controlled by a pulsed positive feedback loop in which kinase expression is activated by pulses of Spo0A phosphorylation. This pulsed positive feedback architecture provides a more robust mechanism for setting deferral times than constitutive kinase expression. Finally, using mathematical modeling, we show how pulsing and time delays together enable "polyphasic" positive feedback, in which different parts of a feedback loop are active at different times. Polyphasic feedback can enable more accurate tuning of long deferral times. Together, these results suggest that Bacillus subtilis uses a pulsed positive feedback loop to implement a "timer" that operates over timescales much longer than a cell cycle.

  6. HDACi: cellular effects, opportunities for restorative dentistry.

    LENUS (Irish Health Repository)

    Duncan, H F

    2011-12-01

    Acetylation of histone and non-histone proteins alters gene expression and induces a host of cellular effects. The acetylation process is homeostatically balanced by two groups of cellular enzymes, histone acetyltransferases (HATs) and histone deacetylases (HDACs). HAT activity relaxes the structure of the human chromatin, rendering it transcriptionally active, thereby increasing gene expression. In contrast, HDAC activity leads to gene silencing. The enzymatic balance can be \\'tipped\\' by histone deacetylase inhibitors (HDACi), leading to an accumulation of acetylated proteins, which subsequently modify cellular processes including stem cell differentiation, cell cycle, apoptosis, gene expression, and angiogenesis. There is a variety of natural and synthetic HDACi available, and their pleiotropic effects have contributed to diverse clinical applications, not only in cancer but also in non-cancer areas, such as chronic inflammatory disease, bone engineering, and neurodegenerative disease. Indeed, it appears that HDACi-modulated effects may differ between \\'normal\\' and transformed cells, particularly with regard to reactive oxygen species accumulation, apoptosis, proliferation, and cell cycle arrest. The potential beneficial effects of HDACi for health, resulting from their ability to regulate global gene expression by epigenetic modification of DNA-associated proteins, also offer potential for application within restorative dentistry, where they may promote dental tissue regeneration following pulpal damage.

  7. Cellular Senescence: A Translational Perspective

    Directory of Open Access Journals (Sweden)

    James L. Kirkland

    2017-07-01

    Full Text Available Cellular senescence entails essentially irreversible replicative arrest, apoptosis resistance, and frequently acquisition of a pro-inflammatory, tissue-destructive senescence-associated secretory phenotype (SASP. Senescent cells accumulate in various tissues with aging and at sites of pathogenesis in many chronic diseases and conditions. The SASP can contribute to senescence-related inflammation, metabolic dysregulation, stem cell dysfunction, aging phenotypes, chronic diseases, geriatric syndromes, and loss of resilience. Delaying senescent cell accumulation or reducing senescent cell burden is associated with delay, prevention, or alleviation of multiple senescence-associated conditions. We used a hypothesis-driven approach to discover pro-survival Senescent Cell Anti-apoptotic Pathways (SCAPs and, based on these SCAPs, the first senolytic agents, drugs that cause senescent cells to become susceptible to their own pro-apoptotic microenvironment. Several senolytic agents, which appear to alleviate multiple senescence-related phenotypes in pre-clinical models, are beginning the process of being translated into clinical interventions that could be transformative.

  8. Cellular Senescence: A Translational Perspective.

    Science.gov (United States)

    Kirkland, James L; Tchkonia, Tamara

    2017-07-01

    Cellular senescence entails essentially irreversible replicative arrest, apoptosis resistance, and frequently acquisition of a pro-inflammatory, tissue-destructive senescence-associated secretory phenotype (SASP). Senescent cells accumulate in various tissues with aging and at sites of pathogenesis in many chronic diseases and conditions. The SASP can contribute to senescence-related inflammation, metabolic dysregulation, stem cell dysfunction, aging phenotypes, chronic diseases, geriatric syndromes, and loss of resilience. Delaying senescent cell accumulation or reducing senescent cell burden is associated with delay, prevention, or alleviation of multiple senescence-associated conditions. We used a hypothesis-driven approach to discover pro-survival Senescent Cell Anti-apoptotic Pathways (SCAPs) and, based on these SCAPs, the first senolytic agents, drugs that cause senescent cells to become susceptible to their own pro-apoptotic microenvironment. Several senolytic agents, which appear to alleviate multiple senescence-related phenotypes in pre-clinical models, are beginning the process of being translated into clinical interventions that could be transformative. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Effects of simulated weightlessness on cellular morphology and biological characteristics of cell lines SGC-7901 and HFE-145

    National Research Council Canada - National Science Library

    Zhu, M; Jin, X W; Wu, B Y; Nie, J L; Li, Y H

    2014-01-01

    We investigated the effects of simulated weightlessness on cellular morphology, proliferation, cell cycle, and apoptosis of the human gastric carcinoma cell line SGC-7901 and the human gastric normal cell line HFE-145...

  10. Probabilistic cellular automata.

    Science.gov (United States)

    Agapie, Alexandru; Andreica, Anca; Giuclea, Marius

    2014-09-01

    Cellular automata are binary lattices used for modeling complex dynamical systems. The automaton evolves iteratively from one configuration to another, using some local transition rule based on the number of ones in the neighborhood of each cell. With respect to the number of cells allowed to change per iteration, we speak of either synchronous or asynchronous automata. If randomness is involved to some degree in the transition rule, we speak of probabilistic automata, otherwise they are called deterministic. With either type of cellular automaton we are dealing with, the main theoretical challenge stays the same: starting from an arbitrary initial configuration, predict (with highest accuracy) the end configuration. If the automaton is deterministic, the outcome simplifies to one of two configurations, all zeros or all ones. If the automaton is probabilistic, the whole process is modeled by a finite homogeneous Markov chain, and the outcome is the corresponding stationary distribution. Based on our previous results for the asynchronous case-connecting the probability of a configuration in the stationary distribution to its number of zero-one borders-the article offers both numerical and theoretical insight into the long-term behavior of synchronous cellular automata.

  11. Predictability in cellular automata.

    Science.gov (United States)

    Agapie, Alexandru; Andreica, Anca; Chira, Camelia; Giuclea, Marius

    2014-01-01

    Modelled as finite homogeneous Markov chains, probabilistic cellular automata with local transition probabilities in (0, 1) always posses a stationary distribution. This result alone is not very helpful when it comes to predicting the final configuration; one needs also a formula connecting the probabilities in the stationary distribution to some intrinsic feature of the lattice configuration. Previous results on the asynchronous cellular automata have showed that such feature really exists. It is the number of zero-one borders within the automaton's binary configuration. An exponential formula in the number of zero-one borders has been proved for the 1-D, 2-D and 3-D asynchronous automata with neighborhood three, five and seven, respectively. We perform computer experiments on a synchronous cellular automaton to check whether the empirical distribution obeys also that theoretical formula. The numerical results indicate a perfect fit for neighbourhood three and five, which opens the way for a rigorous proof of the formula in this new, synchronous case.

  12. Physiological and pathological consequences of cellular senescence.

    Science.gov (United States)

    Burton, Dominick G A; Krizhanovsky, Valery

    2014-11-01

    Cellular senescence, a permanent state of cell cycle arrest accompanied by a complex phenotype, is an essential mechanism that limits tumorigenesis and tissue damage. In physiological conditions, senescent cells can be removed by the immune system, facilitating tumor suppression and wound healing. However, as we age, senescent cells accumulate in tissues, either because an aging immune system fails to remove them, the rate of senescent cell formation is elevated, or both. If senescent cells persist in tissues, they have the potential to paradoxically promote pathological conditions. Cellular senescence is associated with an enhanced pro-survival phenotype, which most likely promotes persistence of senescent cells in vivo. This phenotype may have evolved to favor facilitation of a short-term wound healing, followed by the elimination of senescent cells by the immune system. In this review, we provide a perspective on the triggers, mechanisms and physiological as well as pathological consequences of senescent cells.

  13. PMP27 PROMOTES PEROXISOMAL PROLIFERATION

    NARCIS (Netherlands)

    MARSHALL, PA; KRIMKEVICH, YI; LARK, RH; DYER, JM; VEENHUIS, M; GOODMAN, JM; Krimkevich, Yelena I.; Lark, Richard H.; Dyer, John M.; Goodman, Joel M.

    Peroxisomes perform many essential functions in eukaryotic cells. The weight of evidence indicates that these organelles divide by budding from preexisting peroxisomes. This process is not understood at the molecular level. Peroxisomal proliferation can be induced in Saccharomyces cerevisiae by

  14. Environment Aware Cellular Networks

    KAUST Repository

    Ghazzai, Hakim

    2015-02-01

    The unprecedented rise of mobile user demand over the years have led to an enormous growth of the energy consumption of wireless networks as well as the greenhouse gas emissions which are estimated currently to be around 70 million tons per year. This significant growth of energy consumption impels network companies to pay huge bills which represent around half of their operating expenditures. Therefore, many service providers, including mobile operators, are looking for new and modern green solutions to help reduce their expenses as well as the level of their CO2 emissions. Base stations are the most power greedy element in cellular networks: they drain around 80% of the total network energy consumption even during low traffic periods. Thus, there is a growing need to develop more energy-efficient techniques to enhance the green performance of future 4G/5G cellular networks. Due to the problem of traffic load fluctuations in cellular networks during different periods of the day and between different areas (shopping or business districts and residential areas), the base station sleeping strategy has been one of the main popular research topics in green communications. In this presentation, we present several practical green techniques that provide significant gains for mobile operators. Indeed, combined with the base station sleeping strategy, these techniques achieve not only a minimization of the fossil fuel consumption but also an enhancement of mobile operator profits. We start with an optimized cell planning method that considers varying spatial and temporal user densities. We then use the optimal transport theory in order to define the cell boundaries such that the network total transmit power is reduced. Afterwards, we exploit the features of the modern electrical grid, the smart grid, as a new tool of power management for cellular networks and we optimize the energy procurement from multiple energy retailers characterized by different prices and pollutant

  15. Survival rate of eukaryotic cells following electrophoretic nanoinjection.

    Science.gov (United States)

    Simonis, Matthias; Hübner, Wolfgang; Wilking, Alice; Huser, Thomas; Hennig, Simon

    2017-01-25

    Insertion of foreign molecules such as functionalized fluorescent probes, antibodies, or plasmid DNA to living cells requires overcoming the plasma membrane barrier without harming the cell during the staining process. Many techniques such as electroporation, lipofection or microinjection have been developed to overcome the cellular plasma membrane, but they all result in reduced cell viability. A novel approach is the injection of cells with a nanopipette and using electrophoretic forces for the delivery of molecules. The tip size of these pipettes is approximately ten times smaller than typical microinjection pipettes and rather than pressure pulses as delivery method, moderate DC electric fields are used to drive charged molecules out of the tip. Here, we show that this approach leads to a significantly higher survival rate of nanoinjected cells and that injection with nanopipettes has a significantly lower impact on the proliferation behavior of injected cells. Thus, we propose that injection with nanopipettes using electrophoretic delivery is an excellent alternative when working with valuable and rare living cells, such as primary cells or stem cells.

  16. Dietary bovine lactoferrin increases intestinal cell proliferation in neonatal piglets.

    Science.gov (United States)

    Reznikov, Elizabeth A; Comstock, Sarah S; Yi, Cuiyi; Contractor, Nikhat; Donovan, Sharon M

    2014-09-01

    Lactoferrin is a bioactive milk protein that stimulates cell proliferation in vitro; however, limited in vivo evidence exists to allow lactoferrin to be incorporated into infant formula. Herein, the effect of dietary bovine lactoferrin (bLF) on neonatal intestinal growth and maturation was investigated guided by the hypothesis that bLF would increase cellular proliferation leading to functional differences in neonatal piglets. Colostrum-deprived piglets were fed formula containing 0.4 [control (Ctrl)], 1.0 (LF1), or 3.6 (LF3) g bLF/L for the first 7 or 14 d of life. To provide passive immunity, sow serum was provided orally during the first 36 h of life. Intestinal cell proliferation, histomorphology, mucosal DNA concentration, enzyme activity, gene expression, and fecal bLF content were measured. Intestinal enzyme activity, DNA concentration, and villus length were unaffected by bLF. However, crypt proliferation was 60% greater in LF1- and LF3-fed piglets than in Ctrl piglets, and crypt depth and area were 20% greater in LF3-fed piglets than in Ctrl piglets. Crypt cells from LF3-fed piglets had 3-fold higher β-catenin mRNA expression than did crypt cells from Ctrl piglets. Last, feces of piglets fed bLF contained intact bLF, suggesting that some bLF was resistant to digestion and could potentially affect intestinal proliferation through direct interaction with intestinal epithelial cells. This study is the first to our knowledge to show that dietary bLF stimulates crypt cell proliferation in vivo. The increased β-catenin expression indicates that Wnt signaling may in part mediate the stimulatory effect of bLF on intestinal cell proliferation. © 2014 American Society for Nutrition.

  17. The Concerted Action of Type 2 and Type 3 Deiodinases Regulates the Cell Cycle and Survival of Basal Cell Carcinoma Cells.

    Science.gov (United States)

    Miro, Caterina; Ambrosio, Raffaele; De Stefano, Maria Angela; Di Girolamo, Daniela; Di Cicco, Emery; Cicatiello, Annunziata Gaetana; Mancino, Giuseppina; Porcelli, Tommaso; Raia, Maddalena; Del Vecchio, Luigi; Salvatore, Domenico; Dentice, Monica

    2017-04-01

    Thyroid hormones (THs) mediate pleiotropic cellular processes involved in metabolism, cellular proliferation, and differentiation. The intracellular hormonal environment can be tailored by the type 1 and 2 deiodinase enzymes D2 and D3, which catalyze TH activation and inactivation respectively. In many cellular systems, THs exert well-documented stimulatory or inhibitory effects on cell proliferation; however, the molecular mechanisms by which they control rates of cell cycle progression have not yet been entirely clarified. We previously showed that D3 depletion or TH treatment influences the proliferation and survival of basal cell carcinoma (BCC) cells. Surprisingly, we also found that BCC cells express not only sustained levels of D3 but also robust levels of D2. The aim of the present study was to dissect the contribution of D2 to TH metabolism in the BCC context, and to identify the molecular changes associated with cell proliferation and survival induced by TH and mediated by D2 and D3. We used the CRISPR/Cas9 technology to genetically deplete D2 and D3 in BCC cells and studied the consequences of depletion on cell cycle progression and on cell death. Cell cycle progression was analyzed by fluorescence activated cell sorting analysis of synchronized cells, and the apoptosis rate by annexin V incorporation. Mechanistic investigations revealed that D2 inactivation accelerates cell cycle progression thereby enhancing the proportion of S-phase cells and cyclin D1 expression. Conversely, D3 mutagenesis drastically suppressed cell proliferation and enhanced apoptosis of BCC cells. Furthermore, the basal apoptotic rate was oppositely regulated in D2- and D3-depleted cells. Our results indicate that BCC cells constitute an example in which the TH signal is finely tuned by the concerted expression of opposite-acting deiodinases. The dual regulation of D2 and D3 expression plays a critical role in cell cycle progression and cell death by influencing cyclin D1-mediated

  18. Morphology, proliferation, and osteogenic differentiation of mesenchymal stem cells cultured on titanium, tantalum, and chromium surfaces

    DEFF Research Database (Denmark)

    Stiehler, Maik; Lind, M.; Mygind, Tina

    2007-01-01

    the interactions between human mesenchymal stem cells (MSCs) and smooth surfaces of titanium (Ti), tantalum (Ta), and chromium (Cr). Mean cellular area was quantified using fluorescence microscopy (4 h). Cellular proliferation was assessed by (3)H-thymidine incorporation and methylene blue cell counting assays (4...... with the other surfaces tested. Cells cultured on Cr demonstrated reduced spreading and proliferation. In conclusion, Ta metal, as an alternative for Ti, can be considered as a promising biocompatible material, whereas further studies are needed to fully understand the role of Cr and its alloys in bone implants...

  19. Simvastatin Modulates Mesenchymal Stromal Cell Proliferation and Gene Expression

    Science.gov (United States)

    Zanette, Dalila Lucíola; Lorenzi, Julio Cesar Cetrulo; Panepucci, Rodrigo Alexandre; Palma, Patricia Vianna Bonini; dos Santos, Daiane Fernanda; Prata, Karen Lima; Silva, Wilson Araújo

    2015-01-01

    Statins are widely used hypocholesterolemic drugs that block the mevalonate pathway, responsible for the biosysnthesis of cholesterol. However, statins also have pleiotropic effects that interfere with several signaling pathways. Mesenchymal stromal cells (MSC) are a heterogeneous mixture of cells that can be isolated from a variety of tissues and are identified by the expression of a panel of surface markers and by their ability to differentiate in vitro into osteocytes, adipocytes and chondrocytes. MSC were isolated from amniotic membranes and bone marrows and characterized based on ISCT (International Society for Cell Therapy) minimal criteria. Simvastatin-treated cells and controls were directly assayed by CFSE (Carboxyfluorescein diacetate succinimidyl ester) staining to assess their cell proliferation and their RNA was used for microarray analyses and quantitative PCR (qPCR). These MSC were also evaluated for their ability to inhibit PBMC (peripheral blood mononuclear cells) proliferation. We show here that simvastatin negatively modulates MSC proliferation in a dose-dependent way and regulates the expression of proliferation-related genes. Importantly, we observed that simvastatin increased the percentage of a subset of smaller MSC, which also were actively proliferating. The association of MSC decreased size with increased pluripotency and the accumulating evidence that statins may prevent cellular senescence led us to hypothesize that simvastatin induces a smaller subpopulation that may have increased ability to maintain the entire pool of MSC and also to protect them from cellular senescence induced by long-term cultures/passages in vitro. These results may be important to better understand the pleiotropic effects of statins and its effects on the biology of cells with regenerative potential. PMID:25874574

  20. Cosserat modeling of cellular solids

    NARCIS (Netherlands)

    Onck, P.R.

    2002-01-01

    Cellular solids inherit their macroscopic mechanical properties directly from the cellular microstructure. However, the characteristic material length scale is often not small compared to macroscopic dimensions, which limits the applicability of classical continuum-type constitutive models. Cosserat

  1. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

    Science.gov (United States)

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

  2. Cellular communication through light.

    Directory of Open Access Journals (Sweden)

    Daniel Fels

    Full Text Available Information transfer is a fundamental of life. A few studies have reported that cells use photons (from an endogenous source as information carriers. This study finds that cells can have an influence on other cells even when separated with a glass barrier, thereby disabling molecule diffusion through the cell-containing medium. As there is still very little known about the potential of photons for intercellular communication this study is designed to test for non-molecule-based triggering of two fundamental properties of life: cell division and energy uptake. The study was performed with a cellular organism, the ciliate Paramecium caudatum. Mutual exposure of cell populations occurred under conditions of darkness and separation with cuvettes (vials allowing photon but not molecule transfer. The cell populations were separated either with glass allowing photon transmission from 340 nm to longer waves, or quartz being transmittable from 150 nm, i.e. from UV-light to longer waves. Even through glass, the cells affected cell division and energy uptake in neighboring cell populations. Depending on the cuvette material and the number of cells involved, these effects were positive or negative. Also, while paired populations with lower growth rates grew uncorrelated, growth of the better growing populations was correlated. As there were significant differences when separating the populations with glass or quartz, it is suggested that the cell populations use two (or more frequencies for cellular information transfer, which influences at least energy uptake, cell division rate and growth correlation. Altogether the study strongly supports a cellular communication system, which is different from a molecule-receptor-based system and hints that photon-triggering is a fine tuning principle in cell chemistry.

  3. Empirical multiscale networks of cellular regulation.

    Directory of Open Access Journals (Sweden)

    Benjamin de Bivort

    2007-10-01

    Full Text Available Grouping genes by similarity of expression across multiple cellular conditions enables the identification of cellular modules. The known functions of genes enable the characterization of the aggregate biological functions of these modules. In this paper, we use a high-throughput approach to identify the effective mutual regulatory interactions between modules composed of mouse genes from the Alliance for Cell Signaling (AfCS murine B-lymphocyte database which tracks the response of approximately 15,000 genes following chemokine perturbation. This analysis reveals principles of cellular organization that we discuss along four conceptual axes. (1 Regulatory implications: the derived collection of influences between any two modules quantifies intuitive as well as unexpected regulatory interactions. (2 Behavior across scales: trends across global networks of varying resolution (composed of various numbers of modules reveal principles of assembly of high-level behaviors from smaller components. (3 Temporal behavior: tracking the mutual module influences over different time intervals provides features of regulation dynamics such as duration, persistence, and periodicity. (4 Gene Ontology correspondence: the association of modules to known biological roles of individual genes describes the organization of functions within coexpressed modules of various sizes. We present key specific results in each of these four areas, as well as derive general principles of cellular organization. At the coarsest scale, the entire transcriptional network contains five divisions: two divisions devoted to ATP production/biosynthesis and DNA replication that activate all other divisions, an "extracellular interaction" division that represses all other divisions, and two divisions (proliferation/differentiation and membrane infrastructure that activate and repress other divisions in specific ways consistent with cell cycle control.

  4. Engineering Cellular Metabolism

    DEFF Research Database (Denmark)

    Nielsen, Jens; Keasling, Jay

    2016-01-01

    Metabolic engineering is the science of rewiring the metabolism of cells to enhance production of native metabolites or to endow cells with the ability to produce new products. The potential applications of such efforts are wide ranging, including the generation of fuels, chemicals, foods, feeds...... of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation....

  5. Review of cellular mechanotransduction

    Science.gov (United States)

    Wang, Ning

    2017-06-01

    Living cells and tissues experience physical forces and chemical stimuli in the human body. The process of converting mechanical forces into biochemical activities and gene expression is mechanochemical transduction or mechanotransduction. Significant advances have been made in understanding mechanotransduction at the cellular and molecular levels over the last two decades. However, major challenges remain in elucidating how a living cell integrates signals from mechanotransduction with chemical signals to regulate gene expression and to generate coherent biological responses in living tissues in physiological conditions and diseases.

  6. Engineering Cellular Metabolism

    DEFF Research Database (Denmark)

    Nielsen, Jens; Keasling, Jay

    2016-01-01

    of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation.......Metabolic engineering is the science of rewiring the metabolism of cells to enhance production of native metabolites or to endow cells with the ability to produce new products. The potential applications of such efforts are wide ranging, including the generation of fuels, chemicals, foods, feeds...

  7. Simulation of a cellular automat with an oriented bootstrap rule

    Science.gov (United States)

    Duarte, J. A. M. S.

    1989-06-01

    The evolution of a cellular automat with a culling or bootstrap condition on the minimum number of neighbours for survival has been simulated. The introduction of an orientational constraint converts the lattice from isotropic to semidirected. Simulations of systems of up to 230 million sites are found to be compatible with a threshold value of p=0.966±0.01.

  8. Novel Immune Modulating Cellular Vaccine for Prostate Cancer Immunotherapy

    Science.gov (United States)

    2016-10-01

    cellular vaccine product. 15. SUBJECT TERMS dendritic cell vaccine, dendritic cells electroporated with RNA, immune checkpoint blockade, local CTLA-4...dendritic cell vaccine, dendritic cells electroporated with RNA, immune checkpoint blockade, local CTLA4 modulation, prostate cancer...7: Monitor tumor burden (time to palpable tumor) and monitor survival. Harvest prostate complex/tumor and analyze tumor weight , tumor grade

  9. Anti-proliferation effect of blue light-emitting diodes against antibiotic-resistant Helicobacter pylori.

    Science.gov (United States)

    Ma, Jianwei; Hiratsuka, Takahiro; Etoh, Tsuyoshi; Akada, Junko; Fujishima, Hajime; Shiraishi, Norio; Yamaoka, Yoshio; Inomata, Masafumi

    2017-12-07

    Infection by Helicobacter pylori is implicated in a wide range of upper gastrointestinal diseases. Owing to the rapid emergence of antibiotic-resistant strains of H. pylori, the development of novel treatment modalities for antibiotic-resistant H. pylori infection is a key priority. Blue light-emitting diodes (LED) may represent a unique option owing to their antimicrobial effect. In this study, we aimed to evaluate the anti-proliferative effect of blue LED against antibiotic-resistant H. pylori. Ten antibiotic-resistant strains and one sensitive H. pylori strain were used in this study. After irradiation by blue LED along time course, the viability of H. pylori was evaluated by enumerating colony forming units. Morphological changes in H. pylori were observed using a scanning electron microscope. Reductase activity was measured as an indicator of bacterial cellular activity. Total reactive oxygen species was monitored using fluorescence intensity and fluorescence microscope imaging. After irradiation by blue LED, the numbers of H. pylori in all the strains were significantly reduced compared to control group. The H. pylori exhibited a short rod-shaped morphology after irradiation; no such change was observed in H. pylori not exposed to blue LED. Re-irradiation of surviving strain after the initial irradiation also exhibited the same anti-proliferation effect. After blue LED irradiation, bacterial cellular activity was lower and total reactive oxygen species production was significantly higher in blue LED group, compared to that in control. Blue LED could be a new treatment to eradicate infection with antibiotic-resistant H. pylori. This article is protected by copyright. All rights reserved.

  10. Ethylene Inhibits Cell Proliferation of the Arabidopsis Root Meristem.

    Science.gov (United States)

    Street, Ian H; Aman, Sitwat; Zubo, Yan; Ramzan, Aleena; Wang, Xiaomin; Shakeel, Samina N; Kieber, Joseph J; Schaller, G Eric

    2015-09-01

    The root system of plants plays a critical role in plant growth and survival, with root growth being dependent on both cell proliferation and cell elongation. Multiple phytohormones interact to control root growth, including ethylene, which is primarily known for its role in controlling root cell elongation. We find that ethylene also negatively regulates cell proliferation at the root meristem of Arabidopsis (Arabidopsis thaliana). Genetic analysis indicates that the inhibition of cell proliferation involves two pathways operating downstream of the ethylene receptors. The major pathway is the canonical ethylene signal transduction pathway that incorporates CONSTITUTIVE TRIPLE RESPONSE1, ETHYLENE INSENSITIVE2, and the ETHYLENE INSENSITIVE3 family of transcription factors. The secondary pathway is a phosphorelay based on genetic analysis of receptor histidine kinase activity and mutants involving the type B response regulators. Analysis of ethylene-dependent gene expression and genetic analysis supports SHORT HYPOCOTYL2, a repressor of auxin signaling, as one mediator of the ethylene response and furthermore, indicates that SHORT HYPOCOTYL2 is a point of convergence for both ethylene and cytokinin in negatively regulating cell proliferation. Additional analysis indicates that ethylene signaling contributes but is not required for cytokinin to inhibit activity of the root meristem. These results identify key elements, along with points of cross talk with cytokinin and auxin, by which ethylene negatively regulates cell proliferation at the root apical meristem. © 2015 American Society of Plant Biologists. All Rights Reserved.

  11. Tissue expression of squamous cellular carcinoma antigen and Ki67 in hepatocellular carcinoma-correlation with prognosis: a historical prospective study.

    Science.gov (United States)

    Schmilovitz-Weiss, Hemda; Tobar, Ana; Halpern, Marisa; Levy, Izhar; Shabtai, Esther; Ben-Ari, Ziv

    2011-12-07

    Squamous cellular carcinoma antigen (SCCA) is overexpressed in hepatocellular carcinoma (HCC) tissue and in sera of HCC patients. Our aim was to assess hepatic SCCA immunostaining in a series of HCCs and to correlate its presence with cell proliferation, apoptosis and clinical outcome. Sixty-one HCC patients were included. Liver specimens were obtained either by biopsy (n = 17) or surgically (resection 27, transplantation 17). Immunostaining for AFP, Ki-67, SCCA and TUNEL assay were performed. SCCA staining was detected in 83.6% of specimens. A statistical significant correlation was found between negative SCCA staining and mortality (p = 0.026) and a higher immunostaining score for Ki67 (p = 0.017). Positive SCCA staining was associated with well and moderate differentiated tumors (p = 0.022). Using multiple logistic regression analysis, Ki67 and TUNEL assay were found to be significant independent predictors of negative SCCA immunostaining. The area under the receiver operator characteristic curve was 0.87. Kaplan-Meier survival analysis revealed a significant difference between the patient group with positive versus negative SCCA immunostaining relating to survival time (p = 0.0106). Cox proportional hazard regression analysis demonstrated that Ki67 immunostaining and liver transplantation or resection were independently associated with mortality. SCCA is overexpressed in HCC. SCCA status is associated with cell proliferation, apoptosis and survival. SCCA and Ki67 staining can predict survival. Our study results support a potential association of negative SCCA expression with other markers of poor outcome in HCC. More studies are needed to clarify the role of SCCA in HCC and expand the knowledge of the SCCA antigen in HCC patients. © 2011 Schmilovitz-Weiss et al; licensee BioMed Central Ltd.

  12. Tissue expression of squamous cellular carcinoma antigen and Ki67 in hepatocellular carcinoma-correlation with prognosis: A historical prospective study

    Directory of Open Access Journals (Sweden)

    Schmilovitz-Weiss Hemda

    2011-12-01

    Full Text Available Abstract Background Squamous cellular carcinoma antigen (SCCA is overexpressed in hepatocellular carcinoma (HCC tissue and in sera of HCC patients. Our aim was to assess hepatic SCCA immunostaining in a series of HCCs and to correlate its presence with cell proliferation, apoptosis and clinical outcome. Methods Sixty-one HCC patients were included. Liver specimens were obtained either by biopsy (n = 17 or surgically (resection 27, transplantation 17. Immunostaining for AFP, Ki-67, SCCA and TUNEL assay were performed. Results SCCA staining was detected in 83.6% of specimens. A statistical significant correlation was found between negative SCCA staining and mortality (p = 0.026 and a higher immunostaining score for Ki67 (p = 0.017. Positive SCCA staining was associated with well and moderate differentiated tumors (p = 0.022. Using multiple logistic regression analysis, Ki67 and TUNEL assay were found to be significant independent predictors of negative SCCA immunostaining. The area under the receiver operator characteristic curve was 0.87. Kaplan-Meier survival analysis revealed a significant difference between the patient group with positive versus negative SCCA immunostaining relating to survival time (p = 0.0106. Cox proportional hazard regression analysis demonstrated that Ki67 immunostaining and liver transplantation or resection were independently associated with mortality. Conclusions SCCA is overexpressed in HCC. SCCA status is associated with cell proliferation, apoptosis and survival. SCCA and Ki67 staining can predict survival. Our study results support a potential association of negative SCCA expression with other markers of poor outcome in HCC. More studies are needed to clarify the role of SCCA in HCC and expand the knowledge of the SCCA antigen in HCC patients.

  13. Spatial distribution and cellular composition of adult brain proliferative zones in the teleost, Gymnotus omarorum

    Directory of Open Access Journals (Sweden)

    Valentina eOlivera-Pasilio

    2014-09-01

    Full Text Available Proliferation of stem/progenitor cells during development provides for the generation of mature cell types in the CNS. While adult brain proliferation is highly restricted in the mammals, it is widespread in teleosts. The extent of adult neural proliferation in the weakly electric fish, Gymnotus omarorum has not yet been described. To address this, we used double thymidine analog pulse-chase labeling of proliferating cells to identify brain proliferation zones, characterize their cellular composition, and analyze the fate of newborn cells in adult G. omarorum. Short thymidine analog chase periods revealed the ubiquitous distribution of adult brain proliferation, similar to other teleosts, particularly Apteronotus leptorhynchus. Proliferating cells were abundant at the ventricular-subventricular lining of the ventricular-cisternal system, adjacent to the telencephalic subpallium, the diencephalic preoptic region and hypothalamus, and the mesencephalic tectum opticum and torus semicircularis. Extraventricular proliferation zones, located distant from the ventricular-cisternal system surface, were found in all divisions of the rombencephalic cerebellum. We also report a new adult proliferation zone at the caudal-lateral border of the electrosensory lateral line lobe. All proliferation zones showed a heterogeneous cellular composition. The use of short (24hs and long (30d chase periods revealed abundant fast cycling cells (potentially intermediate amplifiers, sparse slow cycling (potentially stem cells, cells that appear to have entered a quiescent state, and cells that might correspond to migrating newborn neural cells. Their abundance and migration distance differed among proliferation zones: greater numbers and longer range and/or pace of migrating cells were associated with subpallial and cerebellar proliferation zones.

  14. The thorny path linking cellular senescence to organismalaging

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-08-09

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

  15. Effects of IGFBP-2 on proliferation and differentiation in neural stem cell line C17.2

    Directory of Open Access Journals (Sweden)

    Deng Y

    2017-07-01

    Full Text Available Yujia Deng,1 Lei Wang,1,2 Lite Ge,1,3 Da Duan,1 Yi Zhuo,1 Ting Yuan,1 Weiping Yan,1 Peiqi Huang,1 Xiaohua Teng,1 Ming Lu1,3 1Department of Neurosurgery, The Second Affiliated Hospital of Hunan Normal University (163 Hospital of the People’s Liberation Army, Changsha, 2Department of Neurosurgery, Affiliated Haikou Hospital, Xiangya School of Central South University, Haikou, 3Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, People’s Republic of China Objective: Insulin-like growth factor binding protein-2 (IGFBP-2, a member of a highly conserved family of six insulin-like growth factor binding proteins (IGFBPs, can regulate several cellular processes through IGF-dependent or IGF-independent pathway. Recent studies have provided solid evidence for the importance to delineate that olfactory ensheathing cells (OEC-conditioned medium (OCM can not only facilitate the differentiation of neural stem cell line (C17.2 into neurons, but also promote the survival and proliferation. We have previously reported that IGFBP-2 was detected in OCM. This study is designed to investigate the roles of IGFBP-2 for the regulation of C17.2 differentiation and proliferation.Methods and results: IGFBP-2 was identified and upregulated in OCM to compare with astrocytes-conditioned medium by shotgun proteomics and semiquantitative proteomic analysis. In order to investigate whether exogenous IGFBP-2 could stimulate proliferation in C17.2 cells and differentiate it into glia or neuron, we used various concentrations of IGFBP-2 to induce C17.2 cells which were cultured in DMEM/F12. The results showed that exogenous IGFBP-2 can promote proliferation in C17.2 cells, but had little effect on differentiation. Interestingly, we also found that IGFBP-2 could induce C17.2 cells to differentiate into astrocytes, while inhibiting their differentiation into neurons in a dose

  16. Domestic Politics and Nuclear Proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chul Min; Yim, Man Sung [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    The external security threat is known as the most important factor of nuclear weapons program, the domestic politics situation can also affect the nuclear proliferation decision of a country. For example, when a leader wants nuclear weapons as an ultimate weapon, the domestic politics situation can determine the effectiveness of the weapons program of a country. This study analyzes the current knowledge of the relationship between domestic politics and nuclear proliferation and suggests the main challenges of the quantitative models trying to calculate nuclear proliferation risk of countries. The domestic politics status is one of the most important indicators of nuclear program. However, some variables have never been used in quantitative analyses; for example, number of veto players and the public opinion on nuclear weapons; despite they are considered to be important in various qualitative studies. Future studies should focus on how should they be coded and how can they be linked with existing domestic politics variables.

  17. Integrated cellular systems

    Science.gov (United States)

    Harper, Jason C.

    The generation of new three-dimensional (3D) matrices that enable integration of biomolecular components and whole cells into device architectures, without adversely altering their morphology or activity, continues to be an expanding and challenging field of research. This research is driven by the promise that encapsulated biomolecules and cells can significantly impact areas as diverse as biocatalysis, controlled delivery of therapeutics, environmental and industrial process monitoring, early warning of warfare agents, bioelectronics, photonics, smart prosthetics, advanced physiological sensors, portable medical diagnostic devices, and tissue/organ replacement. This work focuses on the development of a fundamental understanding of the biochemical and nanomaterial mechanisms that govern the cell directed assembly and integration process. It was shown that this integration process relies on the ability of cells to actively develop a pH gradient in response to evaporation induced osmotic stress, which catalyzes silica condensation within a thin 3D volume surrounding the cells, creating a functional bio/nano interface. The mechanism responsible for introducing functional foreign membrane-bound proteins via proteoliposome addition to the silica-lipid-cell matrix was also determined. Utilizing this new understanding, 3D cellular immobilization capabilities were extended using sol-gel matrices endowed with glycerol, trehalose, and media components. The effects of these additives, and the metabolic phase of encapsulated S. cerivisiase cells, on long-term viability and the rate of inducible gene expression was studied. This enabled the entrapment of cells within a novel microfluidic platform capable of simultaneous colorimetric, fluorescent, and electrochemical detection of a single analyte, significantly improving confidence in the biosensor output. As a complementary approach, multiphoton protein lithography was utilized to engineer 3D protein matrices in which to

  18. Spreading endothelial cell dysfunction in response to necrotic trophoblasts. Soluble factors released from endothelial cells that have phagocytosed necrotic shed trophoblasts reduce the proliferation of additional endothelial cells.

    Science.gov (United States)

    Chen, Q; Ding, J X; Liu, B; Stone, P; Feng, Y J; Chamley, L

    2010-11-01

    The pathogenesis of preeclampsia is not clear but the disease is characterised by systemic endothelial cell dysfunction that is considered to be triggered by a placental factor. Necrotic trophoblastic debris that is deported in the maternal blood is one possible placental trigger for preeclampsia. Syncytial knots were first associated with preeclampsia over 100 years ago. However, syncytial knots are very large and most are trapped in the pulmonary capillaries making it difficult to envisage how they could lead to widespread systemic endothelial cell dysfunction. This study was undertaken to examine whether conditioned medium from endothelial cells that have phagocytosed necrotic trophoblastic debris could adversely affect the proliferation or survival of fresh endothelial cells. Trophoblastic cellular debris, harvested from placental explants was added to endothelial cell monolayers directly or after induction of necrosis by freeze-thawing. Conditioned medium from the endothelial cell cultures was exposed to fresh endothelial cells and their proliferation measured by Alamar Blue, and CyQUANTNF cell proliferation assays. Endothelial cell death was examined by a fluorogenic caspase-3 activity assay and LDH release. Conditioned medium from endothelial cells that had phagocytosed necrotic but not apoptotic trophoblastic debris significantly inhibited the proliferation of fresh endothelial cells but did not induce their death. The conditioned medium also reduced cell-surface endoglin expression by fresh endothelial cells. These results confirm that phagocytosis of necrotic trophoblastic debris by endothelial cells results in the secretion of soluble factors that might explain how necrotic trophoblastic debris trapped in the pulmonary capillaries could induce systemic endothelial cell dysfunction. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Cellular image classification

    CERN Document Server

    Xu, Xiang; Lin, Feng

    2017-01-01

    This book introduces new techniques for cellular image feature extraction, pattern recognition and classification. The authors use the antinuclear antibodies (ANAs) in patient serum as the subjects and the Indirect Immunofluorescence (IIF) technique as the imaging protocol to illustrate the applications of the described methods. Throughout the book, the authors provide evaluations for the proposed methods on two publicly available human epithelial (HEp-2) cell datasets: ICPR2012 dataset from the ICPR'12 HEp-2 cell classification contest and ICIP2013 training dataset from the ICIP'13 Competition on cells classification by fluorescent image analysis. First, the reading of imaging results is significantly influenced by one’s qualification and reading systems, causing high intra- and inter-laboratory variance. The authors present a low-order LP21 fiber mode for optical single cell manipulation and imaging staining patterns of HEp-2 cells. A focused four-lobed mode distribution is stable and effective in optical...

  20. CELLULAR RESPONSES TO EGG-OIL (CHARISMON©

    Directory of Open Access Journals (Sweden)

    Jürgen Bereiter-Hahn

    2014-01-01

    Full Text Available Egg-oil (Charismon© is known for its beneficial action in wound healing and other skin irritancies and its antibacterial activity. The physiological basis for these actions has been investigated using cells in culture: HaCaT-cells (immortalized human keratinocytes, human endothelial cells in culture (HUVEC, peripheral blood mononuclear lymphocytes (PBML and a full thickness human skin model (FTSM. Emphasis was on the influence of egg-oil on cell migration and IL-8 production in HaCaT cells, respiration, mitochondrial membrane potential, reactive oxygen (ROS production and proliferation in HUVEC and HaCaT cells, cytokine and interleukin production in PBML and UV-light induced damage of FTSM. IL-8 production by HaCaT cells is stimulated by egg-oil whilst in phythemagglutinin-activated PBMLs production of the interleukins IL-2, IL-6, IL-10 and IFN-γ and TFN-α is reduced. ROS-production after H2O2 stimulation first is enhanced but later on reduced. Respiration becomes activated due to partial uncoupling of the mitochondrial respiratory chain and proliferation of HaCaT and HUVEC is reduced. Recovery of human epidermis cells in FTSM after UV-irradiation is strongly supported by egg-oil. These results support the view that egg-oil acts through reduction of inflammatory processes and ROS production. Both these processes are equally important in cellular aging as in healing of chronic wounds.

  1. Non-monotonic changes in clonogenic cell survival induced by disulphonated aluminum phthalocyanine photodynamic treatment in a human glioma cell line

    Directory of Open Access Journals (Sweden)

    Muralidhar K

    2010-04-01

    Full Text Available Abstract Background Photodynamic therapy (PDT involves excitation of sensitizer molecules by visible light in the presence of molecular oxygen, thereby generating reactive oxygen species (ROS through electron/energy transfer processes. The ROS, thus produced can cause damage to both the structure and the function of the cellular constituents resulting in cell death. Our preliminary investigations of dose-response relationships in a human glioma cell line (BMG-1 showed that disulphonated aluminum phthalocyanine (AlPcS2 photodynamically induced loss of cell survival in a concentration dependent manner up to 1 μM, further increases in AlPcS2concentration (>1 μM were, however, observed to decrease the photodynamic toxicity. Considering the fact that for most photosensitizers only monotonic dose-response (survival relationships have been reported, this result was unexpected. The present studies were, therefore, undertaken to further investigate the concentration dependent photodynamic effects of AlPcS2. Methods Concentration-dependent cellular uptake, sub-cellular localization, proliferation and photodynamic effects of AlPcS2 were investigated in BMG-1 cells by absorbance and fluorescence measurements, image analysis, cell counting and colony forming assays, flow cytometry and micronuclei formation respectively. Results The cellular uptake as a function of extra-cellular AlPcS2 concentrations was observed to be biphasic. AlPcS2 was distributed throughout the cytoplasm with intense fluorescence in the perinuclear regions at a concentration of 1 μM, while a weak diffuse fluorescence was observed at higher concentrations. A concentration-dependent decrease in cell proliferation with accumulation of cells in G2+M phase was observed after PDT. The response of clonogenic survival after AlPcS2-PDT was non-monotonic with respect to AlPcS2 concentration. Conclusions Based on the results we conclude that concentration-dependent changes in physico

  2. Adaptation to Survival in Germinal Center is the Initial Step in Onset of Indolent Stage of Multiple Myeloma

    Science.gov (United States)

    Silva, Ariosto S.; Gatenby, Robert A.

    2011-01-01

    Aberrant mutations of centrocytes in germinal centers (GC) can generate two completely different diseases: B-cell lymphomas and monoclonal gammopathy of undetermined significance (MGUS). In this article we use computational models to examine the evolutionary dynamics by which initial adaptation to survival in the GC allows naïve MGUS cells to proliferate in the bone marrow and initiate the evolutionary process that will lead to aggressive multiple myeloma (MM). Our simulations show that MGUS cells may generate bone marrow tumors ranging from indolent to aggressive, depending on the original adaptation in the GC. All these tumors, however, are limited to approximately 15% of the marrow cellularity due to hypoxia-induced quiescence (this correlates with the cellularity that separates MGUS and MM, ~10%). Resistance to hypoxia-induced quiescence and cell death was one of the two major bone marrow adaptations that allowed continued tumor growth and establishment of paracrine cytokine loops, known to increase MM cell replication and de novo multidrug resistance. The second major adaptation was an increase in IL-6-independent growth rate, which correlates with the mutations observed in advanced stage patients. Even though there was an increase in the microvessel density in all simulations, the “angiogenic switch” was not due to a MM angiogenic phenotype, but rather the response of MM cells to the regional hypoxia caused by the increased tumor burden. These results indicate that treatments targeting the adaptation to survival and proliferation in hypoxia, in conjunction with currently available therapies, may have synergistic effects, by delaying tumor growth and reducing cytokine paracrine loops mediated by angiogenic factors. PMID:21958215

  3. Cell proliferation in lymphoid tissue and the seminiferous epithelium under continuous low level irradiation. Final report, 1 June 1967 to 15 July 1973

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J I

    1978-10-19

    The scientific scope and primary objectives of the research program concern investigations on (1) the kinetics of cellular proliferation and differentiation in the immunohematopoietic tissues and the reproductive tissues, and (2) the cellular response and cell population kinetics of these renewal tissues of the body under the stress of continuous low level irradiation. The directions and objectives of the research program have been continually broadened to include investigations on (1) the dynamics of the cellular and humoral immune responses, (2) interactions of host-defense mechanisms, (3) the cell proliferation kinetics in the ovary, and (4) cellular control mechanisms and human tumor cell kinetics.

  4. Lymphocyte Proliferation Response in Patients with Acute and Chronic Brucellosis

    Directory of Open Access Journals (Sweden)

    Khadijeh Khosravi

    2016-05-01

    Full Text Available Abstract Background: Brucella is an intracellular bacterium that causes chronic infection in humans and domestic animals. The underlying mechanisms that cause prolonged illness are complex and not fully understood. Immune responses may have an important role in the chronicity of infection. Here, we evaluated the lymphocyte proliferation responses in patients with chronic and acute brucellosis. Materials and Methods: This descriptive - analytical study was performed on 22 patients with acute brucellosis, 21 patients with chronic brucellosis and 21 healthy people with the similar age, sex and genetic background as control group. Peripheral lymphocytes were isolated using Ficoll and the cellular proliferation was quantified in presence of antigen and phytohemaglutinin-A by MTT method. Results: The brucella antigen-specific stimulation index in patients with chronic brucellosis was significantly lower than the acute brucellosis patients (p=0.001. Also, stimulating the lymphocytes with phytohemaglutinin-A has shown that proliferative response in patients with chronic brucellosis was lower than the other groups (p=0.04. Conclusion: The results indicated that chronic brucellosis inhibits lymphocyte proliferation. This inhibition of lymphocyte proliferation may be due to the induction of anergy.

  5. Simulated Hypergravity Alters Vascular Smooth Muscle Cell Proliferation and Motility

    Science.gov (United States)

    Hunt, Shameka; Bettis, Barika; Harris-Hooker, Sandra; Sanford, Gary L.

    1997-01-01

    The cellular effects of gravity are poorly understood due to its constancy and nonavailability of altered gravitational models. Such an understanding is crucial for prolonged space flights. In these studies, we assessed the influence of centrifugation at 6G (HGrav) on vascular smooth muscle (SMC) mobility and proliferation. Cells were: (a) plated at low density and subjected to HGrav for 24-72 hr for proliferation studies, or (b) grown to confluency, subjected to HGrav, mechanically denuded and monitored for cell movement into the denuded area. Controls were maintained under normogravity. SMC showed a 50% inhibition of growth under HGrav and 10% serum; HGrav and low serum resulted in greater growth inhibition. The rate of movement of SMC into the denuded area was 2-3-fold higher under HGrav in low serum compared to controls, but similar in 10% serum. These studies show that HGrav has significant effects on SMC growth and mobility, which are dependent on serum levels.

  6. Cellular growth and mitochondrial ultrastructure of leishmania (Viannia braziliensis promastigotes are affected by the iron chelator 2,2-dipyridyl.

    Directory of Open Access Journals (Sweden)

    Camila Mesquita-Rodrigues

    Full Text Available Iron is an essential element for the survival of microorganisms in vitro and in vivo, acting as a cofactor of several enzymes and playing a critical role in host-parasite relationships. Leishmania (Viannia braziliensis is a parasite that is widespread in the new world and considered the major etiological agent of American tegumentary leishmaniasis. Although iron depletion leads to promastigote and amastigote growth inhibition, little is known about the role of iron in the biology of Leishmania. Furthermore, there are no reports regarding the importance of iron for L. (V. braziliensis.In this study, the effect of iron on the growth, ultrastructure and protein expression of L. (V. braziliensis was analyzed by the use of the chelator 2,2-dipyridyl. Treatment with 2,2-dipyridyl affected parasites' growth in a dose- and time-dependent manner. Multiplication of the parasites was recovered after reinoculation in fresh culture medium. Ultrastructural analysis of treated promastigotes revealed marked mitochondrial swelling with loss of cristae and matrix and the presence of concentric membranar structures inside the organelle. Iron depletion also induced Golgi disruption and intense cytoplasmic vacuolization. Fluorescence-activated cell sorting analysis of tetramethylrhodamine ester-stained parasites showed that 2,2-dipyridyl collapsed the mitochondrial membrane potential. The incubation of parasites with propidium iodide demonstrated that disruption of mitochondrial membrane potential was not associated with plasma membrane permeabilization. TUNEL assays indicated no DNA fragmentation in chelator-treated promastigotes. In addition, two-dimensional electrophoresis showed that treatment with the iron chelator induced up- or down-regulation of proteins involved in metabolism of nucleic acids and coordination of post-translational modifications, without altering their mRNA levels.Iron chelation leads to a multifactorial response that results in cellular

  7. Biomimetic substrate control of cellular mechanotransduction.

    Science.gov (United States)

    Andalib, Mohammad Nahid; Dzenis, Yuris; Donahue, Henry J; Lim, Jung Yul

    2016-01-01

    Extracellular mechanophysical signals from both static substrate cue and dynamic mechanical loading have strong potential to regulate cell functions. Most of the studies have adopted either static or dynamic cue and shown that each cue can regulate cell adhesion, spreading, migration, proliferation, lineage commitment, and differentiation. However, there is limited information on the integrative control of cell functions by the static and dynamic mechanophysical signals. For example, a majority of dynamic loading studies have tested mechanical stimulation of cells utilizing cultures on flat surfaces without any surface modification. While these approaches have provided significant information on cell mechanotransduction, obtained outcomes may not correctly recapitulate complex cellular mechanosensing milieus in vivo. Several pioneering studies documented cellular response to mechanical stimulations upon cultures with biomimetic substrate modifications. In this min-review, we will highlight key findings on the integrative role of substrate cue (topographic, geometric, etc.) and mechanical stimulation (stretch, fluid shear) in modulating cell function and fate. The integrative approaches, though not fully established yet, will help properly understand cell mechanotransduction under biomimetic mechanophysical environments. This may further lead to advanced functional tissue engineering and regenerative medicine protocols.

  8. Cellular senescence and the aging brain.

    Science.gov (United States)

    Chinta, Shankar J; Woods, Georgia; Rane, Anand; Demaria, Marco; Campisi, Judith; Andersen, Julie K

    2015-08-01

    Cellular senescence is a potent anti-cancer mechanism that arrests the proliferation of mitotically competent cells to prevent malignant transformation. Senescent cells accumulate with age in a variety of human and mouse tissues where they express a complex 'senescence-associated secretory phenotype' (SASP). The SASP includes many pro-inflammatory cytokines, chemokines, growth factors and proteases that have the potential to cause or exacerbate age-related pathology, both degenerative and hyperplastic. While cellular senescence in peripheral tissues has recently been linked to a number of age-related pathologies, its involvement in brain aging is just beginning to be explored. Recent data generated by several laboratories suggest that both aging and age-related neurodegenerative diseases are accompanied by an increase in SASP-expressing senescent cells of non-neuronal origin in the brain. Moreover, this increase correlates with neurodegeneration. Senescent cells in the brain could therefore constitute novel therapeutic targets for treating age-related neuropathologies. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Cellular contractility requires ubiquitin mediated proteolysis.

    Directory of Open Access Journals (Sweden)

    Yuval Cinnamon

    Full Text Available BACKGROUND: Cellular contractility, essential for cell movement and proliferation, is regulated by microtubules, RhoA and actomyosin. The RhoA dependent kinase ROCK ensures the phosphorylation of the regulatory Myosin II Light Chain (MLC Ser19, thereby activating actomyosin contractions. Microtubules are upstream inhibitors of contractility and their depolymerization or depletion cause cells to contract by activating RhoA. How microtubule dynamics regulates RhoA remains, a major missing link in understanding contractility. PRINCIPAL FINDINGS: We observed that contractility is inhibited by microtubules not only, as previously reported, in adherent cells, but also in non-adhering interphase and mitotic cells. Strikingly we observed that contractility requires ubiquitin mediated proteolysis by a Cullin-RING ubiquitin ligase. Inhibition of proteolysis, ubiquitination and neddylation all led to complete cessation of contractility and considerably reduced MLC Ser19 phosphorylation. CONCLUSIONS: Our results imply that cells express a contractility inhibitor that is degraded by ubiquitin mediated proteolysis, either constitutively or in response to microtubule depolymerization. This degradation seems to depend on a Cullin-RING ubiquitin ligase and is required for cellular contractions.

  10. Nuclear Proliferation: A Historical Overview

    Science.gov (United States)

    2008-03-01

    unsuccessful, however, and in 1981 Egypt ratified the Nuclear Non-Proliferation Treaty. In 1982 Egypt’s Hydrometallurgy Pilot Plant for reprocessing...Country Profile: Egypt,” http://www.iaea.org/DataCenter/index.html (accessed ɠ/8/2007>). 1982: Hydrometallurgy Pilot Plant for reprocessing

  11. Nuclear Proliferation Technology Trends Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zentner, Michael D.; Coles, Garill A.; Talbert, Robert J.

    2005-10-04

    A process is underway to develop mature, integrated methodologies to address nonproliferation issues. A variety of methodologies (both qualitative and quantitative) are being considered. All have one thing in common, a need for a consistent set of proliferation related data that can be used as a basis for application. One approach to providing a basis for predicting and evaluating future proliferation events is to understand past proliferation events, that is, the different paths that have actually been taken to acquire or attempt to acquire special nuclear material. In order to provide this information, this report describing previous material acquisition activities (obtained from open source material) has been prepared. This report describes how, based on an evaluation of historical trends in nuclear technology development, conclusions can be reached concerning: (1) The length of time it takes to acquire a technology; (2) The length of time it takes for production of special nuclear material to begin; and (3) The type of approaches taken for acquiring the technology. In addition to examining time constants, the report is intended to provide information that could be used to support the use of the different non-proliferation analysis methodologies. Accordingly, each section includes: (1) Technology description; (2) Technology origin; (3) Basic theory; (4) Important components/materials; (5) Technology development; (6) Technological difficulties involved in use; (7) Changes/improvements in technology; (8) Countries that have used/attempted to use the technology; (9) Technology Information; (10) Acquisition approaches; (11) Time constants for technology development; and (12) Required Concurrent Technologies.

  12. anterior hyaloidal fibrovascular proliferation (ahfvp)

    African Journals Online (AJOL)

    Okonkwo

    fibrovascular proliferation in ischaemic diabetic eyes is known to occur predominantly in the region posterior to the equator, ie, the pre-equatorial fundus. There is a. 5 preponderance of posterior neovascularization occurring in proliferative diabetic retinopathy. This posterior. 7,8,9 proliferative disease in ischaemic diabetic ...

  13. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, Raewyn C., E-mail: raewyn.poulsen@gmail.com; Carr, Andrew J.; Hulley, Philippa A.

    2015-06-19

    The FOXO family of forkhead transcription factors have a pivotal role in determining cell fate in response to oxidative stress. FOXO activity can either promote cell survival or induce cell death. Increased FOXO-mediated cell death has been implicated in the pathogenesis of degenerative diseases affecting musculoskeletal tissues. The aim of this study was to determine the conditions under which one member of the FOXO family, FOXO3a, promotes cell survival as opposed to cell death. Treatment of primary human tenocytes with 1 pM hydrogen peroxide for 18 h resulted in increased protein levels of FOXO3a. In peroxide-treated cells cultured in low serum media, FOXO3a inhibited cell proliferation and protected against apoptosis. However in peroxide treated cells cultured in high serum media, cell proliferation was unchanged but level of apoptosis significantly increased. Similarly, in tenocytes transduced to over-express FOXO3a, cell proliferation was inhibited and level of apoptosis unchanged in cells cultured in low serum. However there was a robust increase in cell death in FOXO3a-expressing cells cultured in high serum. Inhibition of cell proliferation in either peroxide-treated or FOXO3a-expressing cells cultured in high serum protected against apoptosis induction. Conversely, addition of a Chk2 inhibitor to peroxide-treated or FOXO3a-expressing cells overrode the inhibitory effect of FOXO3a on cell proliferation and led to increased apoptosis in cells cultured in low serum. This study demonstrates that proliferating cells may be particularly susceptible to the apoptosis-inducing actions of FOXO3a. Inhibition of cell proliferation by FOXO3a may be a critical event in allowing the pro-survival rather than the pro-apoptotic activity of FOXO3a to prevail. - Highlights: • FOXO3a activity can result in either promotion of cell survival or apoptosis. • The outcome of FOXO3a activation differs in proliferating compared to non-proliferating cells. • Proliferating

  14. TNF-α promotes survival and migration of MSCs under oxidative stress via NF-κB pathway to attenuate intimal hyperplasia in vein grafts.

    Science.gov (United States)

    Bai, Xiao; Xi, Jie; Bi, Yanwen; Zhao, Xin; Bing, Weidong; Meng, Xiangbin; Liu, Yimin; Zhu, Zhonglai; Song, Guangmin

    2017-09-01

    The oxidative stress caused by endothelial injury is involved in intimal hyperplasia (IH) in vein grafts. Mesenchymal stem cells (MSCs) can home to injured intima and promote endothelial repair. However, MSC apoptosis is increased accompanied by decreased functional activity under oxidative stress. Thus, we investigate whether tumour necrosis factor-α (TNF-α) can promote the survival and activity of MSCs under oxidative stress to reduce IH more effectively, and establish what role the NF-κB pathway plays in this. In this study, we preconditioned MSCs with TNF-α ( TNF -α-PC MSCs) for 24 hrs and measured the activation of the IKK/NF-κB pathway. EdU and transwell assays were performed to assess proliferation and migration of TNF -α-PC MSCs. Apoptosis and migration of TNF -α- PC MSCs were evaluated in conditions of oxidative stress by analysis of the expression of Bcl-2 and CXCR4 proteins. TNF -α- PC MSCs were transplanted into a vein graft model, so that cell homing could be tracked, and endothelial apoptosis and IH of vein grafts were measured. The results demonstrated that TNF-α promotes proliferation and migration of MSCs. Furthermore, survival and migration of TNF -α- PC MSCs under oxidative stress were both enhanced. A greater number of MSCs migrated to the intima of vein grafts after preconditioning with TNF-α, and the formation of neointima was significantly reduced. These effects could be partially abolished by IKK XII (NF-κB inhibitor). All these results indicate that preconditioning with TNF-α can promote survival and migration of MSCs under oxidative stress via the NF-κB pathway and thus attenuate IH of vein grafts. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  15. Morphology, proliferation, and osteogenic differentiation of mesenchymal stem cells cultured on titanium, tantalum, and chromium surfaces.

    Science.gov (United States)

    Stiehler, Maik; Lind, Martin; Mygind, Tina; Baatrup, Anette; Dolatshahi-Pirouz, Alireza; Li, Haisheng; Foss, Morten; Besenbacher, Flemming; Kassem, Moustapha; Bünger, Cody

    2008-08-01

    Metallic implants are widely used in orthopedic surgery and dentistry. Durable osseous fixation of an implant requires that osteoprogenitor cells attach and adhere to the implant, proliferate, differentiate into osteoblasts, and produce mineralized matrix. In the present study, we investigated the interactions between human mesenchymal stem cells (MSCs) and smooth surfaces of titanium (Ti), tantalum (Ta), and chromium (Cr). Mean cellular area was quantified using fluorescence microscopy (4 h). Cellular proliferation was assessed by (3)H-thymidine incorporation and methylene blue cell counting assays (4 days). Osteogenic differentiation response was quantified by cell-specific alkaline phosphatase activity (ALP) assay (4 days), expression analysis of bone-related genes (4 days), and mineralization assay (21 days). Undifferentiated and osteogenically stimulated MSCs cultured on the different surfaces showed the same tendencies for proliferation and differentiation. MSCs exposed to Ti surfaces demonstrated enhanced proliferation compared with Ta and Cr surfaces. Cultivation of MSCs on Ta surfaces resulted in significantly increased mean cellular area and cell-specific ALP activity compared with the other surfaces tested. Cells cultured on Cr demonstrated reduced spreading and proliferation. In conclusion, Ta metal, as an alternative for Ti, can be considered as a promising biocompatible material, whereas further studies are needed to fully understand the role of Cr and its alloys in bone implants.

  16. The influence of cellular seeding density in the microencapsulation of hybridoma cells.

    Science.gov (United States)

    Arús, L; Orive, G; Hernández, R; Rodriguez, A; Rojas, A; Pedraz, J L

    2005-01-01

    The aim of this study was to assess the influence of different seeding densities on the function of hybridoma cells (clone 1B5, IgG 2alpha) producing an anti-angiogenic monoclonal antibody (mAb), microencapsulated using a high-voltage electrostatic field. Viable cells were microencapsulated in alginate/poly-L-lysine/alginate (APA) capsules and maintained in tissue culture. Cellular growth rates, production and release of mAb from the capsules were assessed. This study shows that hybridoma cells survive, proliferate and remain functionally competent for over one month in vitro after microencapsulation in APA capsules generated in an electrostatic field. However, the cell seeding density had to be at least 10(7) cells/ml for the microencapsulated cells to be viable and to produce and release mAb through the capsule membrane. The maximum monoclonal antibody concentration in this culture was 29.1 microg/ml by day 17, with a tendency to increase, but capsule breakage impeded the follow-up of this determination.

  17. The effect of an autologous cellular gel-matrix integrated implant system on wound healing

    Directory of Open Access Journals (Sweden)

    Morales Patricio

    2010-06-01

    Full Text Available Abstract Background This manuscript reports the production and preclinical studies to examine the tolerance and efficacy of an autologous cellular gel-matrix integrated implant system (IIS aimed to treat full-thickness skin lesions. Methods The best concentration of fibrinogen and thrombin was experimentally determined by employing 28 formula ratios of thrombin and fibrinogen and checking clot formation and apparent stability. IIS was formed by integrating skin cells by means of the in situ gelification of fibrin into a porous crosslinked scaffold composed of chitosan, gelatin and hyaluronic acid. The in vitro cell proliferation within the IIS was examined by the MTT assay and PCNA expression. An experimental rabbit model consisting of six circular lesions was utilized to test each of the components of the IIS. Then, the IIS was utilized in an animal model to cover a 35% body surface full thickness lesion. Results The preclinical assays in rabbits demonstrated that the IIS was well tolerated and also that IIS-treated rabbit with lesions of 35% of their body surface, exhibited a better survival rate (p = 0,06. Conclusion IIS should be further studied as a new wound dressing which shows promising properties, being the most remarkable its good biological tolerance and cell growth promotion properties.

  18. Changes in cellular mechanical properties during onset or progression of colorectal cancer

    Science.gov (United States)

    Ciasca, Gabriele; Papi, Massimiliano; Minelli, Eleonora; Palmieri, Valentina; De Spirito, Marco

    2016-01-01

    Colorectal cancer (CRC) development represents a multistep process starting with specific mutations that affect proto-oncogenes and tumour suppressor genes. These mutations confer a selective growth advantage to colonic epithelial cells that form first dysplastic crypts, and then malignant tumours and metastases. All these steps are accompanied by deep mechanical changes at the cellular and the tissue level. A growing consensus is emerging that such modifications are not merely a by-product of the malignant progression, but they could play a relevant role in the cancer onset and accelerate its progression. In this review, we focus on recent studies investigating the role of the biomechanical signals in the initiation and the development of CRC. We show that mechanical cues might contribute to early phases of the tumour initiation by controlling the Wnt pathway, one of most important regulators of cell proliferation in various systems. We highlight how physical stimuli may be involved in the differentiation of non-invasive cells into metastatic variants and how metastatic cells modify their mechanical properties, both stiffness and adhesion, to survive the mechanical stress associated with intravasation, circulation and extravasation. A deep comprehension of these mechanical modifications may help scientist to define novel molecular targets for the cure of CRC. PMID:27621568

  19. Nrf2 regulates cellular behaviors and Notch signaling in oral squamous cell carcinoma cells.

    Science.gov (United States)

    Fan, Hong; Paiboonrungruan, Chorlada; Zhang, Xinyan; Prigge, Justin R; Schmidt, Edward E; Sun, Zheng; Chen, Xiaoxin

    2017-11-04

    Oxidative stress is known to play a pivotal role in the development of oral squamous cell carcinoma (OSCC). We have demonstrated that activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway has chemopreventive effects against oxidative stress-associated OSCC. However, Nrf2 have dual roles in cancer development; while it prevents carcinogenesis of normal cells, hyperactive Nrf2 also promotes the survival of cancer cells. This study is aimed to understand the function of Nrf2 in regulating cellular behaviors of OSCC cells, and the potential mechanisms through which Nrf2 facilitates OSCC. We established the Nrf2-overexpressing and Nrf2-knockdown OSCC cell lines, and examined the function of Nrf2 in regulating cell proliferation, migration, invasion, cell cycle and colony formation. Our data showed that Nrf2 overexpression promoted cancer phenotypes in OSCC cells, whereas Nrf2 silencing inhibited these phenotypes. In addition, Nrf2 positively regulated Notch signaling pathway in OSCC cells in vitro. Consistent with this observation, Nrf2 activation in Keap1-/- mice resulted in not only hyperproliferation of squamous epithelial cells in mouse tongue as evidenced by increased expression of PCNA, but also activation of Notch signaling in these cells as evidenced by increased expression of NICD1 and Hes1. In conclusion, Nrf2 regulates cancer behaviors and Notch signaling in OSCC cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Casein kinase II is elevated in solid human tumours and rapidly proliferating non-neoplastic tissue

    DEFF Research Database (Denmark)

    Münstermann, U; Fritz, G; Seitz, G

    1990-01-01

    Protein kinase CKII (i.e. casein kinase II, CKII, NII) is expressed at a higher level in rapidly proliferating tissues and in solid human tumours (e.g. colorectal carcinomas) when compared to the corresponding non-neoplastic colorectal mucosa. This could be shown by (a) Western blotting of cellular...

  1. Polycomb proteins control proliferation and transformation independently of cell cycle checkpoints by regulating DNA replication

    DEFF Research Database (Denmark)

    Piunti, Andrea; Rossi, Alessandra; Cerutti, Aurora

    2014-01-01

    that PRCs regulate cellular proliferation and transformation independently of the Ink4a/Arf-pRb-p53 pathway. We provide evidence that PRCs localize at replication forks, and that loss of their function directly affects the progression and symmetry of DNA replication forks. Thus, we have identified a novel...

  2. Sustained proliferation in cancer: mechanisms and novel therapeutic targets

    Science.gov (United States)

    Arzumanyan, Alla; Kulathinal, Rob J.; Blain, Stacy W.; Holcombe, Randall F.; Mahajna, Jamal; Marino, Maria; Martinez-Chantar, Maria L.; Nawroth, Roman; Sanchez-Garcia, Isidro; Sharma, Dipali; Saxena, Neeraj K.; Singh, Neetu; Vlachostergios, Panagiotis J.; Guo, Shanchun; Honoki, Kanya; Fujii, Hiromasa; Georgakilas, Alexandros G.; Amedei, Amedeo; Niccolai, Elena; Amin, Amr; Ashraf, S. Salman; Boosani, Chandra S.; Guha, Gunjan; Ciriolo, Maria Rosa; Aquilano, Katia; Chen, Sophie; Mohammed, Sulma I.; Azmi, Asfar S.; Bhakta, Dipita; Halicka, Dorota; Nowsheen, Somaira

    2016-01-01

    Proliferation is an important part of cancer development and progression. This is manifest by altered expression and/or activity of cell cycle related proteins. Constitutive activation of many signal transduction pathways also stimulates cell growth. Early steps in tumor development are associated with a fibrogenic response and the development of a hypoxic environment which favors the survival and proliferation of cancer stem cells. Part of the survival strategy of cancer stem cells may manifested by alterations in cell metabolism. Once tumors appear, growth and metastasis may be supported by overproduction of appropriate hormones (in hormonally dependent cancers), by promoting angiogenesis, by undergoing epithelial to mesenchymal transition, by triggering autophagy, and by taking cues from surrounding stromal cells. A number of natural compounds (e.g., curcumin, resveratrol, indole-3-carbinol, brassinin, sulforaphane, epigallocatechin-3-gallate, genistein, ellagitannins, lycopene and quercetin) have been found to inhibit one or more pathways that contribute to proliferation (e.g., hypoxia inducible factor 1, nuclear factor kappa B, phosphoinositide 3 kinase/Akt, insulin-like growth factor receptor 1, Wnt, cell cycle associated proteins, as well as androgen and estrogen receptor signaling). This data, in combination with bioinformatics analyses, will be very important for identifying signaling pathways and molecular targets that may provide early diagnostic markers and/or critical targets for the development of new drugs or drug combinations that block tumor formation and progression. PMID:25892662

  3. p38α negatively regulates survival and malignant selection of transformed bronchioalveolar stem cells.

    Directory of Open Access Journals (Sweden)

    Edwige Voisset

    Full Text Available Lung cancer is the cause of most cancer-related deaths in the Western world. Non-small cell lung cancer accounts for almost 80% of all lung cancers, and 50% of this type are adenocarcinomas. The cellular and molecular origin of this type of lung cancer remains elusive and the mechanisms are poorly known. It is known that K-Ras mutations appear in 25-30% of lung adenocarcinomas and it is the best known single mutation that can be related to lung cancers. Recently, it has been suggested that a putative population of mouse bronchioalveolar stem cells could be considered as the cell of origin of adenocarcinomas. These cells are expanded in the early stages of lung tumorigenesis. We have isolated a population of mouse bronchioalveolar stem cells and induced their transformation by oncogenic K-RasG12. Different approaches have shown that an intracellular network linking the p38α MAPK and the PI3K-Pdk1 pathways is involved in regulating the survival and malignant progression of the transformed cells. Absence of p38α catalytic activity leads to further Pdk1 activation (independent of Akt and Erk activity, enhancing the survival and proliferation of the more malignant lung cancer cells. This specifically selects high Sca-1/Sox9 cells that harbour a stronger colonizing potential, as they maintain their capacity to produce secondary tumors after serial transplantations.

  4. Substrate stiffness orchestrates epithelial cellular heterogeneity with controlled proliferative pattern via E-cadherin/β-catenin mechanotransduction.

    Science.gov (United States)

    Wang, Bingjie; Qin, Peng; Zhao, Hui; Xia, Tie; Wang, Jingyu; Liu, Longwei; Zhu, Lu; Xu, Jing; Huang, Chenyu; Shi, Yan; Du, Yanan

    2016-09-01

    Epithelial cellular heterogeneity has been observed in pathological tissues with abnormal matrix stiffness and cells cultured on rigid substrates. However, it remains unclear how matrix stiffness influences cellular heterogeneity formation in multi-cellular population. Here, we demonstrated that cellular heterogeneity regulated by substrate stiffness is evident starting from the initial single-cell stage (indicated by cellular Young's modulus and morphology) until the resulting multi-cellular stage (indicated by cellular functions) through distinguished proliferative patterns. Epithelial cells on soft substrate proliferated in a neighbor-dependent manner with stronger E-cadherin expression and more homogeneous E-cadherin/β-catenin localization compared to those on coverslips, which resulted in reduced heterogeneity in downstream cellular functions of the multi-cellular population. In particular, decreased heterogeneity in human embryonic stem cells upon expansion and endodermal induction was achieved on soft substrate. Overall, our work provides new insights on mechanotransduction during epithelial proliferation which regulates the formation of cellular heterogeneity and potentially provides a highly efficient approach to regulate stem cell fate by fine-tuning substrate stiffness. This study demonstrates that cellular heterogeneity regulated by substrate stiffness is evident starting from the initial single-cell stage until the resulting multi-cellular stage through distinguished proliferative patterns. During this process, E-cadherin/β-catenin mechanotransduction is found to play important role in substrate stiffness-regulated epithelial cellular heterogeneity formation. In particular, decreased heterogeneity in human embryonic stem cells upon expansion and endodermal induction is achieved on soft substrate. Hence, we believe that this work not only provides new insights on mechanotransduction of E-cadherin/β-catenin which regulates the formation of cellular

  5. Poly(ADP-ribose) polymerase-1 is a survival factor for radiation-exposed intestinal epithelial stem cells in vivo

    Science.gov (United States)

    Ishizuka, Satoshi; Martin, Kareen; Booth, Catherine; Potten, Christopher S.; de Murcia, Gilbert; Bürkle, Alexander; Kirkwood, Thomas B. L.

    2003-01-01

    Poly(ADP-ribose) polymerase-1 (PARP-1) is a key enzyme mediating the cellular response to DNA strand breaks. It plays a critical role in genomic stability and survival of proliferating cells in culture undergoing DNA damage. Intestinal epithelium is the most proliferative tissue in the mammalian body and its stem cells show extreme sensitivity to low-level genotoxic stress. We investigated the role of PARP-1 in the in vivo damage response of intestinal stem cells in crypts of PARP-1–/– and control mice following whole-body γ-irradiation (1 Gy). In the PARP-1–/– mice there was a significant delay during the first 6 h in the transient p53 accumulation in stem cells whereas an increased number of cells were positive for p21CIP1/WAF1. Either no or only marginal differences were noted in MDM2 expression, apoptosis, induction of or recovery from mitotic blockage, or inhibition of DNA synthesis. We further observed a dose-dependent reduction in crypt survival measured at 4 days post-irradiation in control mice, and this crypt-killing effect was significantly potentiated in PARP-1–/– mice. Our results thus establish that PARP-1 acts as a survival factor for intestinal stem cells in vivo and suggest a functional link with early p53 and p21CIP1/WAF1 responses. PMID:14576306

  6. Aging and atherosclerosis: mechanisms, functional consequences, and potential therapeutics for cellular senescence.

    Science.gov (United States)

    Wang, Julie C; Bennett, Martin

    2012-07-06

    Atherosclerosis is classed as a disease of aging, such that increasing age is an independent risk factor for the development of atherosclerosis. Atherosclerosis is also associated with premature biological aging, as atherosclerotic plaques show evidence of cellular senescence characterized by reduced cell proliferation, irreversible growth arrest and apoptosis, elevated DNA damage, epigenetic modifications, and telomere shortening and dysfunction. Not only is cellular senescence associated with atherosclerosis, there is growing evidence that cellular senescence promotes atherosclerosis. This review examines the pathology of normal vascular aging, the evidence for cellular senescence in atherosclerosis, the mechanisms underlying cellular senescence including reactive oxygen species, replication exhaustion and DNA damage, the functional consequences of vascular cell senescence, and the possibility that preventing accelerated cellular senescence is a therapeutic target in atherosclerosis.

  7. The caspase-3/p120 RasGAP stress-sensing module reduces liver cancer incidence but does not affect overall survival in gamma-irradiated and carcinogen-treated mice.

    Science.gov (United States)

    Vanli, Güliz; Sempoux, Christine; Widmann, Christian

    2017-06-01

    Activation of oncogenes is the initial step in cellular transformation. Oncogenes favor aberrant proliferation, which, at least initially, induces cellular stress. This oncogenic stress can act as a safeguard mechanism against further transformation by inducing senescence or apoptosis. Yet, the few premalignant cells that tolerate and escape these senescent or apoptotic responses are those that will ultimately generate tumors. The caspase-3/p120 RasGAP module is a stress-sensing device that promotes survival under mild stress conditions. A point mutation in RasGAP that prevents its cleavage by caspase-3 inactivates the pro-survival capacity of the device. When the mice homozygous for this mutation (D455A knock-in mice) are patho-physiologically challenged, they experience much stronger cellular damage than their wild-type counterparts and the affected organs rapidly lose their functionality. We reasoned that the caspase-3/p120 RasGAP module could help premalignant cells to cope with oncogenic stress and hence favor the development of tumors. Using gamma-irradiation and N-ethyl-N-nitrosourea (ENU) as tumor initiators, we assessed the survival advantage that the caspase-3/p120 RasGAP module could provide to premalignant cells. No difference in overall mortality between wild-type and D455A knock-in mice were observed. However, the number of ENU-induced liver tumors in the knock-in mice was higher than in control mice. These results indicate that the caspase-3/p120 RasGAP stress-sensing module impacts on carcinogen-induced liver cancer incidence but not sufficiently so as to affect overall survival. Hence, gamma irradiation and ENU-induced tumorigenesis processes do not critically rely on a survival mechanism that contributes to the maintenance of organ homeostasis in stressed healthy tissues. © 2017 Wiley Periodicals, Inc.

  8. Expression of Erk5 in early stage breast cancer and association with disease free survival identifies this kinase as a potential therapeutic target.

    Directory of Open Access Journals (Sweden)

    Juan Carlos Montero

    Full Text Available BACKGROUND: Breast cancer is the most common neoplasia in women. Even though advances in its treatment have improved disease outcome, some patients relapse. Therefore, attempts to better define the molecular determinants that drive breast cancer cell proliferation may help in defining potential therapeutic targets. Mitogen-activated protein kinases (MAPK play important roles in tumorigenesis. One of them, Erk5, has been linked to the proliferation of breast cancer cells in vitro. Here we have investigated the expression and prognostic value of Erk5 in human breast cancer. METHODOLOGY/PRINCIPAL FINDINGS: Animal and cellular models were used to study Erk5 expression and function in breast cancer. In 84 human breast tumours the expression of Erk5 was analyzed by immunohistochemistry. Active Erk5 (pErk5 was studied by Western blotting. Correlation of Erk5 with clinicopathological parameters and with disease-free survival in early stage breast cancer patients was analyzed. Expression of Erk5 was detected in most patients, and overexpression was found in 20%. Active Erk5 was present in a substantial number of samples, as well as in tumours from an animal breast cancer model. Overexpression of Erk5 was associated with a decrease in disease-free survival time, which was independent of other clinicopathological parameters of prognosis. Transient transfection of a short hairpin RNA (shRNA targeting Erk5, and a stable cell line expressing a dominant negative form of Erk5 (Erk5(AEF, were used to investigate the influence of Erk5 on drugs used in the clinic to treat breast tumours. We found that inhibition of Erk5 decreased cancer cell proliferation and also sensitized these cells to the action of anti-HER2 therapies. CONCLUSIONS/SIGNIFICANCE: Overexpression of Erk5 is an independent predictor of disease-free survival in breast cancer, and may represent a future therapeutic target.

  9. Highly efficient mesenchymal stem cell proliferation on poly-ε-caprolactone nanofibers with embedded magnetic nanoparticles

    Science.gov (United States)

    Daňková, Jana; Buzgo, Matej; Vejpravová, Jana; Kubíčková, Simona; Sovková, Věra; Vysloužilová, Lucie; Mantlíková, Alice; Nečas, Alois; Amler, Evžen

    2015-01-01

    In this study, we have developed a combined approach to accelerate the proliferation of mesenchymal stem cells (MSCs) in vitro, using a new nanofibrous scaffold made by needleless electrospinning from a mixture of poly-ε-caprolactone and magnetic particles. The biological characteristics of porcine MSCs were investigated while cultured in vitro on composite scaffold enriched with magnetic nanoparticles. Our data indicate that due to the synergic effect of the poly-ε-caprolactone nanofibers and magnetic particles, cellular adhesion and proliferation of MSCs is enhanced and osteogenic differentiation is supported. The cellular and physical attributes make this new scaffold very promising for the acceleration of efficient MSC proliferation and regeneration of hard tissues. PMID:26677321

  10. An Orbital Malignant Melanoma Arising in Cellular Blue Nevus in a Patient with Nevus of Ota

    OpenAIRE

    Buntinx-Krieg, Talayesa; Ouyang, Jie; Cartwright, Mont

    2016-01-01

    Melanomas arising from orbital melanocytic proliferations are exceedingly rare. Many questions remain regarding their development and malignant transformation. We report on a 45-year-old Caucasian woman with a nevus of Ota that presented with visual disturbances involving her right eye and was found to have a biopsy-proven cellular blue nevus in the orbital space. Five years later, she presented with proptosis and worsening symptoms. Biopsy at that time showed a cellular blue nevus with areas...

  11. Proliferation of Genetically Modified Human Cells on Electrospun Nanofiber Scaffolds

    Directory of Open Access Journals (Sweden)

    Mandula Borjigin

    2012-01-01

    Full Text Available Gene editing is a process by which single base mutations can be corrected, in the context of the chromosome, using single-stranded oligodeoxynucleotides (ssODNs. The survival and proliferation of the corrected cells bearing modified genes, however, are impeded by a phenomenon known as reduced proliferation phenotype (RPP; this is a barrier to practical implementation. To overcome the RPP problem, we utilized nanofiber scaffolds as templates on which modified cells were allowed to recover, grow, and expand after gene editing. Here, we present evidence that some HCT116-19, bearing an integrated, mutated enhanced green fluorescent protein (eGFP gene and corrected by gene editing, proliferate on polylysine or fibronectin-coated polycaprolactone (PCL nanofiber scaffolds. In contrast, no cells from the same reaction protocol plated on both regular dish surfaces and polylysine (or fibronectin-coated dish surfaces proliferate. Therefore, growing genetically modified (edited cells on electrospun nanofiber scaffolds promotes the reversal of the RPP and increases the potential of gene editing as an ex vivo gene therapy application.

  12. Pigment epithelium-derived factor up-regulation induced by memantine, an N-methyl-D-aspartate receptor antagonist, is involved in increased proliferation of hippocampal progenitor cells.

    Science.gov (United States)

    Namba, T; Yabe, T; Gonda, Y; Ichikawa, N; Sanagi, T; Arikawa-Hirasawa, E; Mochizuki, H; Kohsaka, S; Uchino, S

    2010-05-05

    Memantine is classified as an NMDA receptor antagonist. We recently reported that memantine promoted the proliferation of neural progenitor cells and the production of mature granule neurons in the adult hippocampus. However, the molecular mechanism responsible for the memantine-induced promotion of cellular proliferation remains unknown. In this study we searched for a factor that mediates memantine-induced cellular proliferation, and found that pigment epithelium-derived factor (PEDF), a broad-acting neurotrophic factor, is up-regulated in the dentate gyrus of adult mice after the injection of memantine. PEDF mRNA expression increased significantly by 3.5-fold at 1 day after the injection of memantine. In addition, the expression level of PEDF protein also increased by 1.8-fold at 2 days after the injection of memantine. Immunohistochemical study using anti-PEDF antibody showed that the majority of the PEDF-expressing cells were protoplasmic and perivascular astrocytes. Using a neurosphere assay, we confirmed that PEDF enhanced cellular proliferation under the presence of fibroblast growth factor-2 (FGF-2) and epidermal growth factor (EGF) but was not involved in the multilineage potency of hippocampal progenitor cells. Over expression of PEDF by adeno-associated virus, however, did not stimulate cellular proliferation, suggesting PEDF per se does not promote cellular proliferation in vivo. These findings suggest that the memantine induced PEDF up-regulation is involved in increased proliferation of hippocampal progenitor cells. (c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

  13. Attachment and Proliferation of Osteoblasts on Lithium-Hydroxyapatite Composites

    Directory of Open Access Journals (Sweden)

    Ana Paula M. Shainberg

    2012-01-01

    Full Text Available The biocompatibility and bioactivity properties of hydroxyapatites (HAs modified through lithium addition were investigated. Hydroxyapatites obtained from bovine bone were mixed with lithium carbonate (Li, in the proportions of 0.25, 0.50, 1.00, and 2.00% wt, and sintered at 900°, 1000°, 1100°, 1200°, and 1300°C, creating LiHA samples. The osteoblast culture behavior was assessed in the presence of these LiHA compositions. The cellular interactions were analyzed by evaluating the viability and cellular proliferation, ALP production and collagen secretion. The cytotoxic potential was investigated through measurement of apoptosis and necrosis induction. The process of cellular attachment in the presence of the product of dissolution of LiHA, was evaluated trough fluorescence analysis. The physical characteristics of these materials and their cellular interactions were examined with SEM and EDS. The results of this study indicate that the LiHA ceramics are biocompatible and have variable bioactivities, which can be tailored by different combinations of the concentration of lithium carbonate and the sintering temperature. Our findings suggest that LiHA 0.25% wt, sintered at 1300°C, combines the necessary physical and structural qualities with favorable biocompatibility characteristics, achieving a bioactivity that seems to be adequate for use as a bone implant material.

  14. Proliferation Vulnerability Red Team report

    Energy Technology Data Exchange (ETDEWEB)

    Hinton, J.P.; Barnard, R.W.; Bennett, D.E. [and others

    1996-10-01

    This report is the product of a four-month independent technical assessment of potential proliferation vulnerabilities associated with the plutonium disposition alternatives currently under review by DOE/MD. The scope of this MD-chartered/Sandia-led study was limited to technical considerations that could reduce proliferation resistance during various stages of the disposition processes below the Stored Weapon/Spent Fuel standards. Both overt and covert threats from host nation and unauthorized parties were considered. The results of this study will be integrated with complementary work by others into an overall Nonproliferation and Arms Control Assessment in support of a Secretarial Record of Decision later this year for disposition of surplus U.S. weapons plutonium.

  15. Inhibition of CIP2A attenuates tumor progression by inducing cell cycle arrest and promoting cellular senescence in hepatocellular carcinoma.

    Science.gov (United States)

    Yang, Xue; Qu, Kai; Tao, Jie; Yin, Guozhi; Han, Shaoshan; Liu, Qingguang; Sun, Hao

    2018-01-08

    CIP2A is a recent identified oncogene that inhibits protein phosphatase 2A (PP2A) and stabilizes c-Myc in cancer cells. To investigate the potential oncogenic role and prognostic value of CIP2A, we comprehensively analyzed the CIP2A expression levels in pan-cancer and observed high expression level of CIP2A in majority cancer types, including hepatocellular carcinoma (HCC). Based on a validation cohort including 60 HCC and 20 non-tumorous tissue samples, we further confirmed the high mRNA and protein expression levels of CIP2A in HCC, and found high CIP2A mRNA expression level was associated with unfavorable overall and recurrence-free survival in patients with HCC. Mechanistic investigations revealed that inhibition of CIP2A significantly attenuated cellular proliferation in vitro and tumourigenicity in vivo. Bioinformatic analysis suggested that CIP2A might be involved in regulating cell cycle. Our experimental data further confirmed CIP2A knockdown induced cell cycle arrest at G1 phase. We found accumulated cellular senescence in HCC cells with CIP2A knockdown, companying expression changes of senescence associated proteins (p21, CDK2, CDK4, cyclin D1, MCM7 and FoxM1). Mechanistically, CIP2A knockdown repressed FoxM1 expression and induced FoxM1 dephosphorylation. Moreover, inhibition of PP2A by phosphatase inhibitor rescued the repression of FoxM1. Taken together, our results showed that CIP2A was highly expressed in HCC. Inhibition of CIP2A induced cell cycle arrest and promoted cellular senescence via repressing FoxM1 transcriptional activity, suggesting a potential anti-cancer target for patients with HCC. Copyright © 2017. Published by Elsevier Inc.

  16. The DNA glycosylases OGG1 and NEIL3 influence differentiation potential, proliferation, and senescence-associated signs in neural stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Amilcar [Linnaeus Center in Developmental Biology for Regenerative Medicine (DBRM), Department of Neuroscience, Karolinska Institutet, SE 17177 Stockholm (Sweden); Hermanson, Ola, E-mail: ola.hermanson@ki.se [Linnaeus Center in Developmental Biology for Regenerative Medicine (DBRM), Department of Neuroscience, Karolinska Institutet, SE 17177 Stockholm (Sweden)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer DNA glycosylases OGG1 and NEIL3 are required for neural stem cell state. Black-Right-Pointing-Pointer No effect on cell viability by OGG1 or NEIL3 knockdown in neural stem cells. Black-Right-Pointing-Pointer OGG1 or NEIL3 RNA knockdown result in decreased proliferation and differentiation. Black-Right-Pointing-Pointer Increased HP1{gamma} immunoreactivity after NEIL3 knockdown suggests premature senescence. -- Abstract: Embryonic neural stem cells (NSCs) exhibit self-renewal and multipotency as intrinsic characteristics that are key parameters for proper brain development. When cells are challenged by oxidative stress agents the resulting DNA lesions are repaired by DNA glycosylases through the base excision repair (BER) pathway as a means to maintain the fidelity of the genome, and thus, proper cellular characteristics. The functional roles for DNA glycosylases in NSCs have however remained largely unexplored. Here we demonstrate that RNA knockdown of the DNA glycosylases OGG1 and NEIL3 decreased NSC differentiation ability and resulted in decreased expression of both neuronal and astrocytic genes after mitogen withdrawal, as well as the stem cell marker Musashi-1. Furthermore, while cell survival remained unaffected, NEIL3 deficient cells displayed decreased cell proliferation rates along with an increase in HP1{gamma} immunoreactivity, a sign of premature senescence. Our results suggest that DNA glycosylases play multiple roles in governing essential neural stem cell characteristics.

  17. Nuclear trafficking of secreted factors and cell-surface receptors: new pathways to regulate cell proliferation and differentiation, and involvement in cancers

    Directory of Open Access Journals (Sweden)

    Planque Nathalie

    2006-10-01

    Full Text Available Abstract Secreted factors and cell surface receptors can be internalized by endocytosis and translocated to the cytoplasm. Instead of being recycled or proteolysed, they sometimes translocate to the nucleus. Nuclear import generally involves a nuclear localization signal contained either in the secreted factor or its transmembrane receptor, that is recognized by the importins machinery. In the nucleus, these molecules regulate transcription of specific target genes by direct binding to transcription factors or general coregulators. In addition to the transcription regulation, nuclear secreted proteins and receptors seem to be involved in other important processes for cell life and cellular integrity such as DNA replication, DNA repair and RNA metabolism. Nuclear secreted proteins and transmembrane receptors now appear to induce new signaling pathways to regulate cell proliferation and differentiation. Their nuclear localization is often transient, appearing only during certain phases of the cell cycle. Nuclear secreted and transmembrane molecules regulate the proliferation and differentiation of a large panel of cell types during embryogenesis and adulthood and are also potentially involved in wound healing. Secreted factors such as CCN proteins, EGF, FGFs and their receptors are often detected in the nucleus of cancer cells. Nuclear localization of these molecules has been correlated with tumor progression and poor prognosis for patient survival. Nuclear growth factors and receptors may be responsible for resistance to radiotherapy.

  18. Arachidonoyl-Phospholipid Remodeling in Proliferating Murine T Cells

    Directory of Open Access Journals (Sweden)

    Ando Soichiro

    2004-01-01

    Full Text Available Abstract Backgound Previous studies have shown that the functional capacity of T cells may be modulated by the composition of fatty acids within, and the release of fatty acids from membrane phospholipids, particulary containing arachidonic acid (AA. The remodeling of AA within membrane phospholipids of resting and proliferating CD4+ and CD8+ T cells is examined in this study. Results Splenic T cells were cultured in the presence or absence of anti-CD3 mAb for 48 h then labeled with [3H]AA for 20 min. In unstimulated cells, labeled AA was preferentially incorporated into the phosphoglycerides, phosphatidylcholine (PC followed by phosphatidylinositol (PI and phosphatidylethanolamine (PE. During a subsequent chase in unlabeled medium unstimulated CD4+ and CD8+ T cells demonstrated a significant and highly selective transfer of free, labeled AA into the PC pool. In contrast, proliferating CD4+ and CD8+ T cells distributed labeled [3H]AA predominantly into PI followed by PC and PE. Following a chase in AA-free medium, a decline in the content of [3H]AA-PC was observed in association with a comparable increase in [3H]AA-PE. Subsequent studies revealed that the cold AA content of all PE species was increased in proliferating T cells compared with that in non-cycling cells, but that enrichment in AA was observed only in the ether lipid fractions. Finally, proliferating T cells preincubated with [3H]AA exhibited a significant loss of labeled arachidonate in the PC fraction and an equivalent gain in labeled AA in 1-alk-1'-enyl-2-arachidonoyl-PE during a chase in unlabeled medium. Conclusion This apparent unidirectional transfer of AA from PC to ether-containing PE suggests the existence of a CoA-independent transacylase system in T cells and supports the hypothesis that arachidonoyl phospholipid remodeling may play a role in the regulation of cellular proliferation.

  19. Free fall and cellular automata

    Directory of Open Access Journals (Sweden)

    Pablo Arrighi

    2016-03-01

    Full Text Available Three reasonable hypotheses lead to the thesis that physical phenomena can be described and simulated with cellular automata. In this work, we attempt to describe the motion of a particle upon which a constant force is applied, with a cellular automaton, in Newtonian physics, in Special Relativity, and in General Relativity. The results are very different for these three theories.

  20. P44/WDR77 restricts the sensitivity of proliferating cells to TGFβ signaling

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Pengfei [Department of Breast and Thyroid Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Road, Wuhan, Hubei 430022 (China); Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030 (United States); Gao, Shen [Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030 (United States); Gu, Zhongping [Department of Thoracic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi’an 710038 (China); Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030 (United States); Huang, Tao [Department of Breast and Thyroid Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Road, Wuhan, Hubei 430022 (China); Wang, Zhengxin, E-mail: zhenwang@mdanderson.org [Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030 (United States)

    2014-07-18

    Highlights: • P44/WDR77 causes proliferating cells to become non-responsive to TGFβ signaling. • P44/WDR77 down-regulates TβRII and TβR2 expression. • P44/WDR77 down-regulated TGFβ signaling correlates with lung tumorigenesis. - Abstract: We previously reported that a novel WD-40 domain-containing protein, p44/WDR77, drives quiescent epithelial cells to re-enter the cell cycle and plays an essential role for growth of lung and prostate cancer cells. Transforming growth factor beta (TGFβ) signaling is important in the maintenance of non-transformed cells in the quiescent or slowly cycling stage. However, both non-transformed proliferating cells and human cancer cells are non-responsive to endogenous TGFβ signaling. The mechanism by which proliferating cells become refractory to TGFβ inhibition is not well established. Here, we found that silencing p44/WDR77 increased cellular sensitivity to TGFβ signaling and that this was inversely correlated with decreased cell proliferation. Smad2 or 3 phosphorylation, TGFβ-mediated transcription, and TGFβ2 and TGFβ receptor type II (TβRII) expression were dramatically induced by silencing of p44/WDR77. These data support the hypothesis that p44/WDR77 down-regulates the expression of the TGFβ ligand and its receptor, thereby leading to a cellular non-response to TGFβ signaling. Finally, we found that p44/WDR77 expression was correlated with cell proliferation and decreased TGFβ signaling during lung tumorigenesis. Together, these results suggest that p44/WDR77 expression causes the non-sensitivity of proliferating cells to TGFβ signaling, thereby contributing to cellular proliferation during lung tumorigenesis.

  1. Cellular automata analysis and applications

    CERN Document Server

    Hadeler, Karl-Peter

    2017-01-01

    This book focuses on a coherent representation of the main approaches to analyze the dynamics of cellular automata. Cellular automata are an inevitable tool in mathematical modeling. In contrast to classical modeling approaches as partial differential equations, cellular automata are straightforward to simulate but hard to analyze. In this book we present a review of approaches and theories that allow the reader to understand the behavior of cellular automata beyond simulations. The first part consists of an introduction of cellular automata on Cayley graphs, and their characterization via the fundamental Cutis-Hedlund-Lyndon theorems in the context of different topological concepts (Cantor, Besicovitch and Weyl topology). The second part focuses on classification results: What classification follows from topological concepts (Hurley classification), Lyapunov stability (Gilman classification), and the theory of formal languages and grammars (Kůrka classification). These classifications suggest to cluster cel...

  2. MIMO Communication for Cellular Networks

    CERN Document Server

    Huang, Howard; Venkatesan, Sivarama

    2012-01-01

    As the theoretical foundations of multiple-antenna techniques evolve and as these multiple-input multiple-output (MIMO) techniques become essential for providing high data rates in wireless systems, there is a growing need to understand the performance limits of MIMO in practical networks. To address this need, MIMO Communication for Cellular Networks presents a systematic description of MIMO technology classes and a framework for MIMO system design that takes into account the essential physical-layer features of practical cellular networks. In contrast to works that focus on the theoretical performance of abstract MIMO channels, MIMO Communication for Cellular Networks emphasizes the practical performance of realistic MIMO systems. A unified set of system simulation results highlights relative performance gains of different MIMO techniques and provides insights into how best to use multiple antennas in cellular networks under various conditions. MIMO Communication for Cellular Networks describes single-user,...

  3. MSAT and cellular hybrid networking

    Science.gov (United States)

    Baranowsky, Patrick W., II

    Westinghouse Electric Corporation is developing both the Communications Ground Segment and the Series 1000 Mobile Phone for American Mobile Satellite Corporation's (AMSC's) Mobile Satellite (MSAT) system. The success of the voice services portion of this system depends, to some extent, upon the interoperability of the cellular network and the satellite communication circuit switched communication channels. This paper will describe the set of user-selectable cellular interoperable modes (cellular first/satellite second, etc.) provided by the Mobile Phone and described how they are implemented with the ground segment. Topics including roaming registration and cellular-to-satellite 'seamless' call handoff will be discussed, along with the relevant Interim Standard IS-41 Revision B Cellular Radiotelecommunications Intersystem Operations and IOS-553 Mobile Station - Land Station Compatibility Specification.

  4. Organizational Inertia and Excessive Product Proliferation

    OpenAIRE

    Sakuraki, Rie

    2015-01-01

    This study investigates the internal factors of excessive product proliferation. Since empirical literature on product over-proliferation focused on how to optimize existing product portfolio, the causes of excessive product proliferation have so far attracted little attention. This study employs a case study of Shiseido, a famous Japanese cosmetics company, with particular attention to product proliferation in the Shiseido chain store channel, because external factors are mostly absent from ...

  5. [Effect of Capparis spinosa on fibroblast proliferation and type I collagen production in progressive systemic sclerosis].

    Science.gov (United States)

    Cao, Yue-Lan; Li, Xin; Zheng, Min

    2008-03-01

    To investigate the effects of ethanolic extract from Capparis spinosa (ECS) on the fibroblast proliferation and type I collagen production in normal and progressive systemic sclerosis (PSS). Cellular activity was determined by the MTT method. Apoptosis was detected by flow cytometry analysis of Annexin V-stained cells. The expression levels of type I collagen messenger RNA and protein were analyzed by RT-PCR and western blot analysis. ECS could significantly inhibit the proliferation of fibroblast and reduced the expression of alpha2 (I) collagen mRNA and type I collagen protein in PSS in a dose-and time-dependent manner. ECS did not affect the proliferation of fibroblast and expression of type I collagen mRNA and protein in normal human. ECS could counteract the harmful effects on fibroblast by H2O2. ECS can effectively inhibit the fibroblast proliferation and type I collagen production in PSS.

  6. Vitreous humor and albumin augment the proliferation of cultured retinal precursor cells

    DEFF Research Database (Denmark)

    Yang, Jing; Klassen, Henry; Pries, Mette

    2008-01-01

    Intravitreal injection is an important delivery route for studies involving the transplantation of various types of precursor cells to the retina; however, the effect on these cells of exposure to the vitreous microenvironment has not been specifically investigated. Here vitreous humor...... was evaluated for the potential to influence the proliferation of rat retinal precursor cells in vitro. Cells were isolated at embryonic day 19 and plated in standard proliferation medium in the presence or absence of fluid expressed from porcine vitreous humor. Cellular proliferation at different...... concentrations of vitreous fluid supplementation was quantified by using a (3)H-thymidine incorporation assay. Active components of vitreous fluid were partially characterized by gel filtration chromatography (GFC) and UV spectral analysis. The effect of each vitreous fraction on proliferation was determined...

  7. Prolyl hydroxylase PHD3 enhances the hypoxic survival and G1 to S transition of carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Heidi Högel

    Full Text Available Hypoxia restricts cell proliferation and cell cycle progression at the G1/S interface but at least a subpopulation of carcinoma cells can escape the restriction. In carcinoma hypoxia