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Sample records for affecting cell proliferation

  1. Genistein affects proliferation and migration of bovine oviductal epithelial cells.

    PubMed

    García, Daniela C; Valdecantos, Pablo A; Miceli, Dora C; Roldán-Olarte, Mariela

    2017-03-08

    Genistein is one of the most abundant isoflavones in soybean. This molecule induces cell cycle arrest and apoptosis in different normal and cancer cells. Genistein has been of considerable interest due to its adverse effects on bovine reproduction, altering estrous cycle, implantation and fetal development and producing subfertility or infertility. The objective of this work was to study the effects of genistein on the expression of selected genes involved in the regulation of cell cycle and apoptosis. Primary cultures of bovine oviductal epithelial cells (BOEC) were treated with different genistein concentrations (0.2, 2 and 10μM) to analyze CYCLIN B1, BCL-2 and BAX gene expression by Real-time RT-PCR. Results showed that genistein down-regulated CYCLIN B1 expression, affecting cell cycle progression, and caused a decrease in the BCL-2/BAX ratio starting at 2μM of genistein. In addition, in order to determine if genistein affects BOEC migration, in vitro wound healing assays were performed. A significant reduction in cell migration after 12h of culture was observed at both 0.2 and 10μM genistein concentrations. Also, in the presence of genistein the percentage of mitotic cells decreased, although apoptotic cells percentages were not affected. These findings indicate that genistein has an inhibitory effect on BOEC proliferation and migration, suggesting that it could influence the normal physiology of the oviductal epithelium.

  2. Cell proliferation in type C gastritis affecting the intact stomach

    PubMed Central

    Mac, D; Willis, P; Prescott, R; Lamonby, S; Lynch, D

    2000-01-01

    Aims—Type C gastritis caused by bile reflux has a characteristic appearance, similar to that seen in other forms of chemical gastritis, such as those associated with NSAIDs or alcohol. An increase in mucosal cell proliferation increases the likelihood of a neoplastic clone of epithelial cells emerging, particularly where there is chronic epithelial injury associated with bile reflux. It has been shown previously that type C gastritis is associated with increased cell proliferation in the postsurgical stomach. The aim of this study was to determine cell proliferation in type C gastritis caused by bile reflux affecting the intact stomach. Methods—Specimens from 15 patients with a histological diagnosis of type C gastritis on antral biopsy were obtained from the pathology archives between 1994 and 1997. A control group of nine normal antral biopsies was also selected and all underwent MIB-1 immunostaining. The gastric glands were divided into three zones (zone 1, gastric pit; zone 2, isthmus; and zone 3, gland base) and the numbers of positively staining nuclei for 500 epithelial cell nuclei were counted in each zone to determine the percentage labelling index (LI%). Results—Cell proliferation was significantly higher in all three zones of the gastric glands with type C gastritis compared with controls as follows: zone 1, median LI% in type C gastritis 64.7 (range, 7.8–99.2), controls 4.7 (range, 2.0–11.3); zone 2, median LI% in type C gastritis 94.7 (range, 28.8–98.7), controls 40.2 (range, 23.1–70.3); and zone 3, median LI% in type C gastritis 20.0 (range, 1.3–96.0), controls 2.6 (range, 0.9–8.7). Conclusions—Bile reflux is thought to act as a promoter of gastric carcinogenesis in the postsurgical stomach. The same may be true in the intact stomach. Key Words: cell proliferation • epithelial kinetics • chemical gastritis PMID:11064674

  3. Aging affects initiation and continuation of T cell proliferation.

    PubMed

    Jiang, Jiu; Gross, Diara; Elbaum, Philip; Murasko, Donna M

    2007-04-01

    Aging is associated with a decline in immune responses, particularly within the T cell compartment. While the expansion of specific T cells in response to virus infections is consistently decreased in aged mice, the differences in T cell activation between young and aged mice as demonstrated in each round of proliferation remain poorly defined. In the present study, we utilized the T cell mitogen, ConA, to explore if fewer T cells of aged mice initiate proliferation upon mitogen stimulation or if similar numbers of T cells of aged mice begin proliferation but undergo fewer rounds of division. We also examined whether these age-associated changes in proliferation are reflected by differences in T cell activation by comparing activation markers (CD25, CD69, CD44, and CD62L) on T cells of young and aged mice at each round of proliferation. Not only was the kinetics of the expression of these markers greatly different between young and aged mice on the entire CD8 T cell population, but also at each round of proliferation. Our results demonstrate that a larger percentage of CD8 T cells of aged mice do not proliferate at all upon stimulation. Of the CD8 T cells of aged mice that do proliferate, a larger percentage start later and stop sooner. These results suggest that multiple levels of alteration may need to be considered when trying to maximize the immune response of aged individuals.

  4. Inhibition of cyclooxygenase (COX)-2 affects endothelial progenitor cell proliferation

    SciTech Connect

    Colleselli, Daniela; Bijuklic, Klaudija; Mosheimer, Birgit A.; Kaehler, Christian M. . E-mail: C.M.Kaehler@uibk.ac.at

    2006-09-10

    Growing evidence indicates that inducible cyclooxygenase-2 (COX-2) is involved in the pathogenesis of inflammatory disorders and various types of cancer. Endothelial progenitor cells recruited from the bone marrow have been shown to be involved in the formation of new vessels in malignancies and discussed for being a key point in tumour progression and metastasis. However, until now, nothing is known about an interaction between COX and endothelial progenitor cells (EPC). Expression of COX-1 and COX-2 was detected by semiquantitative RT-PCR and Western blot. Proliferation kinetics, cell cycle distribution and rate of apoptosis were analysed by MTT test and FACS analysis. Further analyses revealed an implication of Akt phosphorylation and caspase-3 activation. Both COX-1 and COX-2 expression can be found in bone-marrow-derived endothelial progenitor cells in vitro. COX-2 inhibition leads to a significant reduction in proliferation of endothelial progenitor cells by an increase in apoptosis and cell cycle arrest. COX-2 inhibition leads further to an increased cleavage of caspase-3 protein and inversely to inhibition of Akt activation. Highly proliferating endothelial progenitor cells can be targeted by selective COX-2 inhibition in vitro. These results indicate that upcoming therapy strategies in cancer patients targeting COX-2 may be effective in inhibiting tumour vasculogenesis as well as angiogenic processes.

  5. Aquaporin-1 plays important role in proliferation by affecting cell cycle progression.

    PubMed

    Galán-Cobo, Ana; Ramírez-Lorca, Reposo; Toledo-Aral, Juan José; Echevarría, Miriam

    2016-01-01

    Aquaporin-1 (AQP1) has been associated with tumor development. Here, we investigated how AQP1 may affect cell proliferation. The proliferative rate of adult carotid body (CB) cells, known to proliferate under chronic hypoxia, was analyzed in wild-type (AQP1(+/+) ) and knock out (AQP1(-/-) ) mice, maintained in normoxia or exposed to hypoxia while BrdU was administered. Fewer numbers of total BrdU(+) and TH-BrdU(+) cells were observed in AQP1(-/-) mice, indicating a role for AQP1 in CB proliferation. Then, by flow cytometry, cell cycle state and proliferation of cells overexpressing AQP1 were compared to those of wild-type cells. In the AQP1-overexpressing cells, we observed higher cell proliferation and percentages of cells in phases S and G2/M and fewer apoptotic cells after nocodazole treatment were detected by annexin V staining. Also in these cells, proteomic assays showed higher expression of cyclin D1 and E1 and microarray analysis revealed changes in many cell proliferation-related molecules, including, Zeb 2, Jun, NF-kβ, Cxcl9, Cxcl10, TNF, and the TNF receptor. Overall, our results indicate that the presence of AQP1 modifies the expression of key cell cycle proteins apparently related to increases in cell proliferation. This contributes to explaining the presence of AQP1 in many different tumors.

  6. Post-transcriptional RNA Regulons Affecting Cell Cycle and Proliferation

    PubMed Central

    Blackinton, Jeff G.

    2014-01-01

    The cellular growth cycle is initiated and maintained by punctual, yet agile, regulatory events involving modifications of cell cycle proteins as well as coordinated gene expression to support cyclic checkpoint decisions. Recent evidence indicates that post-transcriptional partitioning of messenger RNA subsets by RNA-binding proteins help physically localize, temporally coordinate, and efficiently translate cell cycle proteins. This dynamic organization of mRNAs encoding cell cycle components contributes to the overall economy of the cell cycle consistent with the post-transcriptional RNA regulon model of gene expression. This review examines several recent studies demonstrating the coordination of mRNA subsets encoding cell cycle proteins during nuclear export and subsequent coupling to protein synthesis, and discusses evidence for mRNA coordination of p53 targets and the DNA damage response pathway. We consider how these observations may connect to upstream and downstream post-transcriptional coordination and coupling of splicing, export, localization, and translation. Published examples from yeast, nematode, insect, and mammalian systems are discussed, and we consider genetic evidence supporting the conclusion that dysregulation of RNA regulons may promote pathogenic states of growth such as carcinogenesis. PMID:24882724

  7. Low-energy laser irradiation affects satellite cell proliferation and differentiation in vitro.

    PubMed

    Ben-Dov, N; Shefer, G; Irintchev, A; Wernig, A; Oron, U; Halevy, O; Irinitchev, A

    1999-01-11

    Low-energy laser (He-Ne) irradiation was found to promote skeletal muscle regeneration in vivo. In this study, its effect on the proliferation and differentiation of satellite cells in vitro was evaluated. Primary rat satellite cells were irradiated for various time periods immediately after preparation, and thymidine incorporation was determined after 2 days in culture. Laser irradiation affected thymidine incorporation in a bell-shaped manner, with a peak at 3 s of irradiation. Three seconds of irradiation caused an induction of cell-cycle regulatory proteins: cyclin D1, cyclin E and cyclin A in an established line of mouse satellite cells, pmi28, and proliferating cell nuclear antigen (PCNA) in primary rat satellite cells. The induction of cyclins by laser irradiation was compatible with their induction by serum refeeding of the cells. Laser irradiation effect on cell proliferation was dependent on the rat's age. At 3 weeks of age, thymidine incorporation in the irradiated cells was more than twofold higher than that in the controls, while at 6 weeks of age this difference had almost disappeared. Myosin heavy chain (MHC) protein levels were twofold lower in the irradiated than in the control cells, whereas the proliferation of the irradiated cells was twofold higher. Fusion percentage was lower in the irradiated compared to non-irradiated cells. In light of these data, the promoting effect of laser irradiation on skeletal muscle regeneration in vivo may be due to its effect on the activation of early cell-cycle regulatory genes in satellite cells, leading to increased proliferation and to a delay in cell differentiation.

  8. Nuclear orphan receptor TLX affects gene expression, proliferation and cell apoptosis in beta cells.

    PubMed

    Shi, Xiaoli; Xiong, Xiaokan; Dai, Zhe; Deng, Haohua; Sun, Li; Hu, Xuemei; Zhou, Feng; Xu, Yancheng

    Nuclear orphan receptor TLX is an essential regulator of the growth of neural stem cells. However, its exact function in pancreatic islet cells is still unknown. In the present study, gene expression profiling analysis revealed that overexpression of TLX in beta cell line MIN6 causes suppression of 176 genes and upregulation of 49 genes, including a cadre of cell cycle, cell proliferation and cell death control genes, such as Btg2, Ddit3 and Gadd45a. We next examined the effects of TLX overexpression on proliferation, apoptosis and insulin secretion in MIN6 cells. Proliferation analysis using EdU assay showed that overexpression of TLX increased percentage of EdU-positive cells. Cell cycle and apoptosis analysis revealed that overexpression of TLX in MIN6 cells resulted in higher percentage of cells exiting G1 into S-phase, and a 58.8% decrease of cell apoptosis induced by 0.5 mM palmitate. Moreover, TLX overexpression did not cause impairment of insulin secretion. Together, we conclude that TLX is among factors capable of controlling beta cell proliferation and survival, which may serve as a target for the development of novel therapies for diabetes.

  9. Co-cultivation of human aortic smooth muscle cells with epicardial adipocytes affects their proliferation rate.

    PubMed

    Ždychová, J; Čejková, S; Králová Lesná, I; Králová, A; Malušková, J; Janoušek, L; Kazdová, L

    2014-01-01

    The abnormal proliferation of vascular smooth muscle cells (VSMC) is thought to play a role in the pathogenesis of atherosclerosis. Adipocytes produce several bioactive paracrine substances that can affect the growth and migration of VSMCs. Our study focuses on the direct effect of the bioactive substances in conditioned media (CM) that was obtained by incubation with primary adipocyte-derived cell lines, including cell lines derived from both preadipocytes and from more mature cells, on the proliferation rate of human aortic smooth muscle cells (HAoSMCs). We used a Luminex assay to measure the adipokine content of the CM and showed that there was a higher concentration of monocyte chemoattractant protein-1 in renal preadipocyte-CM compared with the HAoSMC control (p<0.5). The addition of both renal preadipocyte- and epicardial adipocyte- CM resulted in the elevated production of vascular endothelial growth factor compared with the control HASoSMC CM (p<0.001). The adiponectin content in renal adipocyte-CM was increased compared to all the remaining adipocyte-CM (p<0.01). Moreover, the results showed a higher proliferation rate of HAoSMCs after co-culture with epicardial adipocyte-CM compared to the HAoSMC control (p<0.05). These results suggest that bioactive substances produced by adipocytes have a stimulatory effect on the proliferation of VSMCs.

  10. Kalanchoe tubiflora extract inhibits cell proliferation by affecting the mitotic apparatus

    PubMed Central

    2012-01-01

    Background Kalanchoe tubiflora (KT) is a succulent plant native to Madagascar, and is commonly used as a medicinal agent in Southern Brazil. The underlying mechanisms of tumor suppression are largely unexplored. Methods Cell viability and wound-healing were analyzed by MTT assay and scratch assay respectively. Cell cycle profiles were analyzed by FACS. Mitotic defects were analyzed by indirect immunofluoresence images. Results An n-Butanol-soluble fraction of KT (KT-NB) was able to inhibit cell proliferation. After a 48 h treatment with 6.75 μg/ml of KT, the cell viability was less than 50% of controls, and was further reduced to less than 10% at higher concentrations. KT-NB also induced an accumulation of cells in the G2/M phase of the cell cycle as well as an increased level of cells in the subG1 phase. Instead of disrupting the microtubule network of interphase cells, KT-NB reduced cell viability by inducing multipolar spindles and defects in chromosome alignment. KT-NB inhibits cell proliferation and reduces cell viability by two mechanisms that are exclusively involved with cell division: first by inducing multipolarity; second by disrupting chromosome alignment during metaphase. Conclusion KT-NB reduced cell viability by exclusively affecting formation of the proper structure of the mitotic apparatus. This is the main idea of the new generation of anti-mitotic agents. All together, KT-NB has sufficient potential to warrant further investigation as a potential new anticancer agent candidate. PMID:22963191

  11. Oral pathogens change proliferation properties of oral tumor cells by affecting gene expression of human defensins.

    PubMed

    Hoppe, T; Kraus, D; Novak, N; Probstmeier, R; Frentzen, M; Wenghoefer, M; Jepsen, S; Winter, J

    2016-10-01

    The impact of oral pathogens onto the generation and variability of oral tumors has only recently been investigated. To get further insights, oral cancer cells were treated with pathogens and additionally, as a result of this bacterial cellular infection, with human defensins, which are as anti-microbial peptide members of the innate immune system. After cell stimulation, proliferation behavior, expression analysis of oncogenic relevant defensin genes, and effects on EGFR signaling were investigated. The expression of oncogenic relevant anti-microbial peptides was analyzed with real-time PCR and immunohistochemistry. Cell culture experiments were performed to examine cellular impacts caused by stimulation, i.e., altered gene expression, proliferation rate, and EGF receptor-dependent signaling. Incubation of oral tumor cells with an oral pathogen (Porphyromonas gingivalis) and human α-defensins led to an increase in cell proliferation. In contrast, another oral bacterium used, Aggregatibacter actinomycetemcomitans, enhanced cell death. The bacteria and anti-microbial peptides exhibited diverse effects on the transcript levels of oncogenic relevant defensin genes and epidermal growth factor receptor signaling. These two oral pathogens exhibited opposite primary effects on the proliferation behavior of oral tumor cells. Nevertheless, both microbe species led to similar secondary impacts on the proliferation rate by modifying expression levels of oncogenic relevant α-defensin genes. In this respect, oral pathogens exerted multiplying effects on tumor cell proliferation. Additionally, human defensins were shown to differently influence epidermal growth factor receptor signaling, supporting the hypothesis that these anti-microbial peptides serve as ligands of EGFR, thus modifying the proliferation behavior of oral tumor cells.

  12. Piper and Vismia species from Colombian Amazonia differentially affect cell proliferation of hepatocarcinoma cells.

    PubMed

    Lizcano, Leandro J; Siles, Maite; Trepiana, Jenifer; Hernández, M Luisa; Navarro, Rosaura; Ruiz-Larrea, M Begoña; Ruiz-Sanz, José Ignacio

    2014-12-30

    There is an increasing interest to identify plant-derived natural products with antitumor activities. In this work, we have studied the effects of aqueous leaf extracts from Amazonian Vismia and Piper species on human hepatocarcinoma cell toxicity. Results showed that, depending on the cell type, the plants displayed differential effects; thus, Vismia baccifera induced the selective killing of HepG2, while increasing cell growth of PLC-PRF and SK-HEP-1. In contrast, these two last cell lines were sensitive to the toxicity by Piper krukoffii and Piper putumayoense, while the Piperaceae did not affect HepG2 growth. All the extracts induced cytotoxicity to rat hepatoma McA-RH7777, but were innocuous (V. baccifera at concentrations < 75 µg/mL) or even protected cells from basal death (P. putumayoense) in primary cultures of rat hepatocytes. In every case, cytotoxicity was accompanied by an intracellular accumulation of reactive oxygen species (ROS). These results provide evidence for the anticancer activities of the studied plants on specific cell lines and suggest that cell killing could be mediated by ROS, thus involving mechanisms independent of the plants free radical scavenging activities. Results also support the use of these extracts of the Vismia and Piper genera with opposite effects as a model system to study the mechanisms of the antitumoral activity against different types of hepatocarcinoma.

  13. Donor age of human platelet lysate affects proliferation and differentiation of mesenchymal stem cells.

    PubMed

    Lohmann, Michael; Walenda, Gudrun; Hemeda, Hatim; Joussen, Sylvia; Drescher, Wolf; Jockenhoevel, Stefan; Hutschenreuter, Gabriele; Zenke, Martin; Wagner, Wolfgang

    2012-01-01

    The regenerative potential declines upon aging. This might be due to cell-intrinsic changes in stem and progenitor cells or to influences by the microenvironment. Mesenchymal stem cells (MSC) raise high hopes in regenerative medicine. They are usually culture expanded in media with fetal calf serum (FCS) or other serum supplements such as human platelet lysate (HPL). In this study, we have analyzed the impact of HPL-donor age on culture expansion. 31 single donor derived HPLs (25 to 57 years old) were simultaneously compared for culture of MSC. Proliferation of MSC did not reveal a clear association with platelet counts of HPL donors or growth factors concentrations (PDGF-AB, TGF-β1, bFGF, or IGF-1), but it was significantly higher with HPLs from younger donors (<35 years) as compared to older donors (>45 years). Furthermore, HPLs from older donors increased activity of senescence-associated beta-galactosidase (SA-βgal). HPL-donor age did not affect the fibroblastoid colony-forming unit (CFU-f) frequency, immunophenotype or induction of adipogenic differentiation, whereas osteogenic differentiation was significantly lower with HPLs from older donors. Concentrations of various growth factors (PDGF-AB, TGF-β1, bFGF, IGF-1) or hormones (estradiol, parathormone, leptin, 1,25 vitamin D3) were not associated with HPL-donor age or MSC growth. Taken together, our data support the notion that aging is associated with systemic feedback mechanisms acting on stem and progenitor cells, and this is also relevant for serum supplements in cell culture: HPLs derived from younger donors facilitate enhanced expansion and more pronounced osteogenic differentiation.

  14. Down-regulation of Wnt10a affects odontogenesis and proliferation in mesenchymal cells

    SciTech Connect

    Liu, Yang Han, Dong Wang, Lei Feng, Hailan

    2013-05-17

    Highlights: •Down-regulation of Wnt10a in dental mesenchymal cells impairs odontogenesis of reassociated tooth germs. •Dspp is down- and up-regulated after Wnt10a-knockdown and overexpression in dental mesenchymal cells. •Down-regulation of Wnt10a inhibits proliferation of dental mesenchymal cells. -- Abstract: The WNT10a mutation has been found in patients with abnormal odontogenesis. In mice, Wnt10a expression is found in the tooth germ, but its role has not yet been elucidated. We aimed to investigate the role of Wnt10a in odontogenesis. Mesenchymal cells of the first mandibular molar germ at the bell stage were isolated, transfected with Wnt10a SiRNA or plasmid, and reassociated with epithelial part of the molar germ. Scrambled SiRNA or empty vector was used in the control group. The reassociated tooth germs were transplanted into mice subrenal capsules. After gene modification, dental mesenchymal cells cultured in vitro were checked for cell proliferation and the expression of Dspp was examined. All 12 reassociated tooth germs in the control group resumed odontogenesis, while only 5 of 12 in the Wnt10a knockdown group developed into teeth. After Wnt10a knockdown, the mesenchymal cells cultured in vitro presented repressed proliferation. Wnt10a knockdown and overexpression led to both down- and up-regulation of Dspp. We conclude that the down-regulation of Wnt10a impairs odontogensis and cell proliferation, and that Wnt10a regulates Dspp expression in mesenchymal cells. These findings help to elucidate the mechanism of abnormal tooth development in patients with the WNT10A mutation.

  15. Regulation of the proliferation of colon cancer cells by compounds that affect glycolysis, including 3-bromopyruvate, 2-deoxyglucose and biguanides.

    PubMed

    Lea, Michael A; Qureshi, Mehreen S; Buxhoeveden, Michael; Gengel, Nicolette; Kleinschmit, Jessica; Desbordes, Charles

    2013-02-01

    In previous studies performed by our group, we observed that 2-deoxyglucose blocked the acidification of the medium used for culture of colon cancer cells caused by incubation with biguanides and it had an additive inhibitory effect on growth. In the present work, we found that 3-bromopyruvate can also prevent the lowering of pH caused by biguanide treatment. 3-Bromopyruvate inhibited colonic cancer cell proliferation, but the effect was not always additive to that of biguanides and an additive effect was more notable in combined treatment with 3-bromopyruvate and 2-deoxyglucose. The induction of alkaline phosphatase activity by butyrate was not consistently affected by combination with other agents that modified glucose metabolism. The drug combinations that were examined inhibited proliferation of wild-type and p53-null cells and affected colonic cancer lines with different growth rates.

  16. Early-age heat exposure affects skeletal muscle satellite cell proliferation and differentiation in chicks.

    PubMed

    Halevy, O; Krispin, A; Leshem, Y; McMurtry, J P; Yahav, S

    2001-07-01

    Exposure of young chicks to thermal conditioning (TC; i.e., 37 degrees C for 24 h) resulted in significantly improved body and muscle growth at a later age. We hypothesized that TC causes an increase in satellite cell proliferation, necessary for further muscle hypertrophy. An immediate increase was observed in satellite cell DNA synthesis in culture and in vivo in response to TC of 3-day-old chicks to levels that were significantly higher than those of control chicks. This was accompanied by a marked induction of insulin-like growth factor-I (IFG-I), but not hepatocyte growth factor in the breast muscle. No significant difference between treatments in plasma IGF-I levels was observed. A marked elevation in muscle regulatory factors on day 5, followed by a decline in cell proliferation on day 6 together with continuous high levels of IGF-I in the TC chick muscle may indicate accelerated cell differentiation. These data suggest a central role for IGF-I in the immediate stimulation of satellite cell myogenic processes in response to heat exposure.

  17. Various light source treatments affect body and skeletal muscle growth by affecting skeletal muscle satellite cell proliferation in broilers.

    PubMed

    Halevy, O; Biran, I; Rozenboim, I

    1998-06-01

    In this study we addressed the effect of various monochromatic light treatments on muscle growth and satellite cell proliferation in broilers (Gallus domesticus). Broilers were reared under green (560 nm), blue (480 nm) and red (660 nm) monochromatic lights and white light as a control from day one until 35 days of age. At five days of age, satellite cells were prepared from the experimental chicks. The number of satellite cells per gram of breast muscle and total number of satellite cells derived from the experimental broilers was substantially higher in the groups reared under green and blue light, compared to the red and white light groups. Growth hormone receptor gene expression was also higher in the former groups. High correlation was found between the breast muscle weight observed on day 35 and the number of satellite cells per gram of breast muscle (r = 0.915) and total number of satellite cells (r = 0.833), derived from the experimental chicks as early as five days of age. In addition, the protein/DNA ratio found in breast muscle at 35 days of age was significantly lower in chicks that were reared under green and blue lights. The lowest ratio which was found in the green group and was twice as low as in the control group, indicates the highest number of nuclei in the former group. As satellite cells are the only source of additional nuclei in skeletal muscles of postnatal animals, our results suggest that the higher muscle weight found in the green and blue light groups was due to increased satellite cell proliferation during the first days of age.

  18. Proliferation of mouse embryonic stem cell progeny and the spontaneous contractile activity of cardiomyocytes are affected by microtopography.

    PubMed

    Biehl, Jesse K; Yamanaka, Satoshi; Desai, Tejal A; Boheler, Kenneth R; Russell, Brenda

    2009-08-01

    The niche in which stem cells reside and differentiate is a complex physicochemical microenvironment that regulates cell function. The role played by three-dimensional physical contours was studied on cell progeny derived from mouse embryonic stem cells using microtopographies created on PDMS (poly-dimethyl-siloxane) membranes. While markers of differentiation were not affected, the proliferation of heterogeneous mouse embryonic stem cell-derived progeny was attenuated by 15 microm-, but not 5 microm-high microprojections. This reduction was reversed by Rho kinase and myosin light chain kinase inhibition, which diminishes the tension generating ability of stress fibers. Purified cardiomyocytes derived from embryonic stem cells also showed significant blunting of proliferation and increased beating rates compared with cells grown on flat substrates. Thus, proliferation of stem cell-derived progeny appears to be regulated by microtopography through tension-generation of contractility in the third-dimension. These results emphasize the importance of topographic cues in the modulation of stem cell progeny behavior.

  19. Moderate and strong static magnetic fields directly affect EGFR kinase domain orientation to inhibit cancer cell proliferation

    PubMed Central

    Wang, Wenchao; Li, Zhiyuan; Liu, Juanjuan; Yang, Xingxing; Ji, Xinmiao; Luo, Yan; Hu, Chen; Hou, Yubin; He, Qianqian; Fang, Jun; Wang, Junfeng; Liu, Qingsong; Li, Guohui; Lu, Qingyou; Zhang, Xin

    2016-01-01

    Static magnetic fields (SMFs) can affect cell proliferation in a cell-type and intensity-dependent way but the mechanism remains unclear. At the same time, although the diamagnetic anisotropy of proteins has been proposed decades ago, the behavior of isolated proteins in magnetic fields has not been directly observed. Here we show that SMFs can affect isolated proteins at the single molecular level in an intensity-dependent manner. We found that Epidermal Growth Factor Receptor (EGFR), a protein that is overexpressed and highly activated in multiple cancers, can be directly inhibited by SMFs. Using Liquid-phase Scanning Tunneling Microscopy (STM) to examine pure EGFR kinase domain proteins at the single molecule level in solution, we observed orientation changes of these proteins in response to SMFs. This may interrupt inter-molecular interactions between EGFR monomers, which are critical for their activation. In molecular dynamics (MD) simulations, 1-9T SMFs caused increased probability of EGFR in parallel with the magnetic field direction in an intensity-dependent manner. A superconducting ultrastrong 9T magnet reduced proliferation of CHO-EGFR cells (Chinese Hamster Ovary cells with EGFR overexpression) and EGFR-expressing cancer cell lines by ~35%, but minimally affected CHO cells. We predict that similar effects of magnetic fields can also be applied to some other proteins such as ion channels. Our paper will help clarify some dilemmas in this field and encourage further investigations in order to achieve a better understanding of the biological effects of SMFs. PMID:27223425

  20. The conflict between cell proliferation and expansion primarily affects stem organogenesis in Arabidopsis.

    PubMed

    Maeda, Saori; Gunji, Shizuka; Hanai, Kenya; Hirano, Tomonari; Kazama, Yusuke; Ohbayashi, Iwai; Abe, Tomoko; Sawa, Shinichiro; Tsukaya, Hirokazu; Ferjani, Ali

    2014-11-01

    Plant shoot organs such as stems, leaves and flowers are derived from specialized groups of stem cells organized at the shoot apical meristem (SAM). Organogenesis involves two major processes, namely cell proliferation and differentiation, whereby the former contributes to increasing the cell number and the latter involves substantial increases in cell volume through cell expansion. Co-ordination between the above processes in time and space is essential for proper organogenesis. To identify regulatory factors involved in proper organogenesis, heavy-ion beam-irradiated de-etiolated (det) 3-1 seeds have been used to identify striking phenotypes in the A#26-2; det3-1 mutant. In addition to the stunted plant stature mimicking det3-1, the A#26-2; det3-1 mutant exhibited stem thickening, increased floral organ number and a fruit shape reminiscent of clavata (clv) mutants. DNA sequencing analysis demonstrated that A#26-2; det3-1 harbors a mutation in the CLV3 gene. Importantly, A#26-2; det3-1 displayed cracks that randomly occurred on the main stem with a frequency of approximately 50%. Furthermore, the double mutants clv3-8 det3-1, clv1-4 det3-1 and clv2-1 det3-1 consistently showed stem cracks with frequencies of approximately 97, 38 and 35%, respectively. Cross-sections of stems further revealed an increase in vascular bundle number, cell number and size in the pith of clv3-8 det3-1 compared with det3-1. These findings suggest that the stem inner volume increase due to clv mutations exerts an outward mechanical stress; that in a det3-1 background (defective in cell expansion) resulted in cracking of the outermost layer of epidermal cells.

  1. miR-342-3p affects hepatocellular carcinoma cell proliferation via regulating NF-κB pathway

    SciTech Connect

    Zhao, Liang; Zhang, Yubao

    2015-02-13

    Recent research indicates that non-coding microRNAs (miRNAs) help regulate basic cellular processes in many types of cancer cells. We hypothesized that overexpression of miR-342-3p might affect proliferation of hepatocellular carcinoma (HCC) cells. After confirming overexpression of miR-342-3p with qRT-PCR, MTT assay showed that HCC cell proliferation was significantly inhibited by miR-342-3p, and that it significantly decreased BrdU-positive cell proliferation by nearly sixfold. Searching for targets using three algorithms we found that miR-342-3p is related to the NF-κB pathway and luciferase assay found that IKK-γ, TAB2 and TAB3 are miR-342-3p target genes. Results of western blot on extracted nuclear proteins of HepG2 and HCT-116 cells showed that miR-342-3p reduced and miR-342-3p-in increased p65 nuclear levels and qRT-PCR found that NF-κB pathway downstream genes were downregulated by miR-342-3p and upregulated by miR-342-3p-in, confirming that miR-342 targets NF-κB pathway. Overexpression of Ikk-γ, TAB2 and TAB3 partially rescued HCC cells proliferation inhibited by miR-342-3p. Using the GSE54751 database we evaluated expression from 10 HCC samples, which strongly suggested downregulation of miR-342-3p and we also found inverse expression between miR-342-3p and its targets IKK-γ, TAB2 and TAB3 from 71 HCC samples. Our results show that miR-342-3p has a significant role in HCC cell proliferation and is suitable for investigation of therapeutic targets. - Highlights: • MiR-342-3p suppresses hepatocellular carcinoma cell proliferation. • MiR-342-3p targets IKK-γ, TAB2 and TAB3 genes. • MiR-342-3p downregulates NF-kB signaling pathway. • MiR-342-3p is downregulated in clinical hepatocellular carcinoma samples. • The expression of miR-342-3p and its target gene is inversely related.

  2. Biofouling of inlet pipes affects water quality in running seawater aquaria and compromises sponge cell proliferation

    PubMed Central

    Mueller, Benjamin; Vermeij, Mark J.A.; van der Geest, Harm H.G.

    2015-01-01

    Marine organism are often kept, cultured, and experimented on in running seawater aquaria. However, surprisingly little attention is given to the nutrient composition of the water flowing through these systems, which is generally assumed to equal in situ conditions, but may change due to the presence of biofouling organisms. Significantly lower bacterial abundances and higher inorganic nitrogen species (nitrate, nitrite, and ammonium) were measured in aquarium water when biofouling organisms were present within a 7-year old inlet pipe feeding a tropical reef running seawater aquaria system, compared with aquarium water fed by a new, biofouling-free inlet pipe. These water quality changes are indicative of the feeding activity and waste production of the suspension- and filter-feeding communities found in the old pipe, which included sponges, bivalves, barnacles, and ascidians. To illustrate the physiological consequences of these water quality changes on a model organism kept in the aquaria system, we investigated the influence of the presence and absence of the biofouling community on the functioning of the filter-feeding sponge Halisarca caerulea, by determining its choanocyte (filter cell) proliferation rates. We found a 34% increase in choanocyte proliferation rates following the replacement of the inlet pipe (i.e., removal of the biofouling community). This indicates that the physiological functioning of the sponge was compromised due to suboptimal food conditions within the aquarium resulting from the presence of the biofouling organisms in the inlet pipe. This study has implications for the husbandry and performance of experiments with marine organisms in running seawater aquaria systems. Inlet pipes should be checked regularly, and replaced if necessary, in order to avoid excessive biofouling and to approach in situ water quality. PMID:26664799

  3. Regulation of PMP22 mRNA by G3BP1 affects cell proliferation in breast cancer cells

    PubMed Central

    2013-01-01

    Background Regulation of mRNAs is one way to control protein levels and thereby important cellular processes such as growth, invasion and apoptosis. G3BPs constitute a family of mRNA-binding proteins, shown to be overexpressed in several cancer types, including breast, colon and pancreas cancer. G3BP has been reported to both stabilize and induce degradation of specific mRNAs. Results Here, we show that G3BP1, but not G3BP2, supports proliferation of several breast cancer cell lines. Global gene expression analyses of G3BP1- and G3BP2-depleted cells indicate that primarily G3BP1, and much less G3BP2, influences mRNA expression levels. Peripheral myelin protein 22 (PMP22) was one gene that was significantly influenced by G3BP1 depletion which led to a 2–3 fold increased expression. Depletion of PMP22 resulted in increased proliferation and the G3BP1-mediated effect on proliferation was not seen upon PMP22-depletion. Conclusions This indicates a novel role for G3BP1 in the regulation of cell proliferation in breast cancer cells, perhaps via a regulatory effect on PMP22 expression. PMID:24321297

  4. Recombinant erythropoietin differently affects proliferation of mesothelioma cells but not sensitivity to cisplatin and pemetrexed.

    PubMed

    Palumbo, Camilla; Battisti, Sonia; Carbone, Daniela; Albonici, Loredana; Alimandi, Maurizio; Bei, Roberto; Modesti, Andrea

    2008-04-01

    The combination of cisplatin and pemetrexed represents the newly established standard of care for patients with unresectable malignant mesothelioma (MM). However, this chemotherapy regimen appears to be associated with an increased prevalence of higher grade anemia as compared to treatment with cisplatin alone. Human recombinant erythropoietin (rHuEpo) is currently used for the treatment of anemia in cancer patients. Still, following the finding that the erythropoietin receptor (EpoR) is expressed by several tumor cells types and after the trials reporting that the recombinant cytokine can adversely affect tumor progression and patient survival, the clinical safety of rHuEpo administration to neoplastic patients has recently been questioned. The observation that the expression of EpoR, variably associated with the expression of the cognate ligand, is a common feature of MM cells prompted us to investigate whether treatment with rHuEpo could elicit proliferative and cytoprotective signals in EpoR-positive MM cell lines. Biochemical responsiveness of MM cells to rHuEpo was demonstrated by the time-course activation of both ERK1/2 and AKT following treatment with the recombinant cytokine. A moderately increased mitogenic activity was observed in two out of five MM cell lines treated with pharmacologically relevant concentrations of rHuEpo. On the other hand, the recombinant cytokine, administered either before or after cisplatin and pemetrexed, failed to interfere with the cytotoxic effects exerted by the chemotherapeutic drugs on the five MM cell lines. According to the presented findings, rHuEpo appears to have an overall limited impact on cell growth and no effect on MM sensitivity to chemotherapy.

  5. Long Non-Coding RNA Reprogramming (ROR) Promotes Cell Proliferation in Colorectal Cancer via Affecting P53

    PubMed Central

    Li, Hong; Jiang, Xiumei; Niu, Xuemei

    2017-01-01

    Background Colorectal cancer (CRC) remains one of the most common lethal malignant tumors worldwide. The correlation between lncRNAs expression and CRC development has not been well identified in the recent literature. This study focused on the role of lncRNA-ROR on CRC progression and development. Material/Methods Quantitative real-time PCR (qRT-PCR) assay was conducted to identify the expression level of lncRNA-ROR. Cell proliferation and viability were examined by MTT assay and colony formation assay. Cell cycle distribution and apoptosis were detected by flow cytometry. Expressions of p53, p21, and FAS protein levels were assessed by Western blotting. CRC cells transfected with lncRNA-shRNA were injection into nude mice to identify the function of lncRNA-ROR on tumorigenesis in vivo. Results The expression level of lncRNA-ROR was elevated in CRC tissues when compared to adjacent tissues (n=78). lncRNA-ROR knockdown significantly suppressed cell proliferation and viability, while lncRNA-ROR overexpression had the opposite effect. Decreased lncRNA-ROR expression enhanced cell apoptosis and triggered cell cycle arrest in G0/G1 phase, while elevated lncRNA-ROR expression presented the opposite effect. Protein levels of p53 and p53 target genes were affected by lncRNA-ROR in vitro, and downregulation of lncRNA-ROR impeded tumorigenesis in vivo. Conclusions Our study demonstrates that lncRNA-ROR participates in controlling CRC proliferation, viability, and apoptosis, partially by modulating p53, which provides potential and prospective therapeutic targets for CRC. PMID:28216611

  6. Long Non-Coding RNA Reprogramming (ROR) Promotes Cell Proliferation in Colorectal Cancer via Affecting P53.

    PubMed

    Li, Hong; Jiang, Xiumei; Niu, Xuemei

    2017-02-20

    BACKGROUND Colorectal cancer (CRC) remains one of the most common lethal malignant tumors worldwide. The correlation between lncRNAs expression and CRC development has not been well identified in the recent literature. This study focused on the role of lncRNA-ROR on CRC progression and development. MATERIAL AND METHODS Quantitative real-time PCR (qRT-PCR) assay was conducted to identify the expression level of lncRNA-ROR. Cell proliferation and viability were examined by MTT assay and colony formation assay. Cell cycle distribution and apoptosis were detected by flow cytometry. Expressions of p53, p21, and FAS protein levels were assessed by Western blotting. CRC cells transfected with lncRNA-shRNA were injection into nude mice to identify the function of lncRNA-ROR on tumorigenesis in vivo. RESULTS The expression level of lncRNA-ROR was elevated in CRC tissues when compared to adjacent tissues (n=78). lncRNA-ROR knockdown significantly suppressed cell proliferation and viability, while lncRNA-ROR overexpression had the opposite effect. Decreased lncRNA-ROR expression enhanced cell apoptosis and triggered cell cycle arrest in G0/G1 phase, while elevated lncRNA-ROR expression presented the opposite effect. Protein levels of p53 and p53 target genes were affected by lncRNA-ROR in vitro, and downregulation of lncRNA-ROR impeded tumorigenesis in vivo. CONCLUSIONS Our study demonstrates that lncRNA-ROR participates in controlling CRC proliferation, viability, and apoptosis, partially by modulating p53, which provides potential and prospective therapeutic targets for CRC.

  7. Age-related BMAL1 change affects mouse bone marrow stromal cell proliferation and osteo-differentiation potential

    PubMed Central

    Chen, Yijia; Xu, Xiaomei; Tan, Zhen; Ye, Cui; Chen, Yangxi

    2012-01-01

    Introduction Aging people's bone regeneration potential is always impaired. Bone marrow stromal cells (MSCs) contain progenitors of osteoblasts. Donor age may affect MSCs’ proliferation and differentiation potential, but the genomic base is still unknown. Due to recent research's indication that a core circadian component, brain and muscle ARNT-like 1 protein (BMAL1), has a role in premature aging, we investigated the normal aging mechanism in mice with their MSCs and Bmal1 gene/protein level. Material and methods 1, 6 and 16 month old C57BL/6 mice were used and the bone marrow stromal cells were gained and cultured at early passage. Bmal1 gene and protein level were detected in these cells. Marrow stromal cells were also induced to differentiate to osteoblasts or adipocytes. Three groups of mice MSCs were compared on proliferation by flow cytometry, on cell senescence by SA-β-gal expression and after osteo-induction on osteogenic potential by the expression of osterix (Osx), alkaline phosphatase (ALP) and osteocalcin (OCN). Results Bmal1 gene and protein level as well as S-phase fraction of the cell cycle decreased in MSCs along with the aging process. At the same time, SA-β-gal+ levels increased, especially in the aged mice MSCs. When induced to be osteogenic, Osx gene expression and ALP activity declined in the mid-age and aged mice MSCs, while OCN protein secretion deteriorated in the aged mice MSCs. Conclusions These findings demonstrate that mouse MSCs changed with their proliferation and osteo-differentiation abilities at different aging stages, and that Bmal1 is related to the normal aging process in MSCs. PMID:22457671

  8. TORC1 signaling inhibition by rapamycin and caffeine affect lifespan, global gene expression, and cell proliferation of fission yeast.

    PubMed

    Rallis, Charalampos; Codlin, Sandra; Bähler, Jürg

    2013-08-01

    Target of rapamycin complex 1 (TORC1) is implicated in growth control and aging from yeast to humans. Fission yeast is emerging as a popular model organism to study TOR signaling, although rapamycin has been thought to not affect cell growth in this organism. Here, we analyzed the effects of rapamycin and caffeine, singly and combined, on multiple cellular processes in fission yeast. The two drugs led to diverse and specific phenotypes that depended on TORC1 inhibition, including prolonged chronological lifespan, inhibition of global translation, inhibition of cell growth and division, and reprograming of global gene expression mimicking nitrogen starvation. Rapamycin and caffeine differentially affected these various TORC1-dependent processes. Combined drug treatment augmented most phenotypes and effectively blocked cell growth. Rapamycin showed a much more subtle effect on global translation than did caffeine, while both drugs were effective in prolonging chronological lifespan. Rapamycin and caffeine did not affect the lifespan via the pH of the growth media. Rapamycin prolonged the lifespan of nongrowing cells only when applied during the growth phase but not when applied after cells had stopped proliferation. The doses of rapamycin and caffeine strongly correlated with growth inhibition and with lifespan extension. This comprehensive analysis will inform future studies into TORC1 function and cellular aging in fission yeast and beyond.

  9. Methamphetamine affects cell proliferation in the medial prefrontal cortex: a new niche for toxicity.

    PubMed

    Kim, Airee; Mandyam, Chitra D

    2014-11-01

    Methamphetamine addicts demonstrate impaired frontal cortical-dependent cognitive function that could result from methamphetamine-induced maladaptive plasticity in the prefrontal cortex. Reduced adult gliogenesis observed in a rodent model of compulsive methamphetamine self-administration could contribute to the maladaptive plasticity in the medial prefrontal cortex (mPFC) as excessive methamphetamine intake is associated with loss of gliogenesis. The present study explored the vulnerability of mPFC progenitors to the duration of various sessions of methamphetamine self-administration in limited and extended access schedule of reinforcement. Proliferation of progenitors via Ki-67 labeling and apoptosis via activated caspase-3 labeling were studied in rats that intravenously self-administered methamphetamine in a limited access (1h/day: short access (ShA)) or extended access (6h/day: long access (LgA)) paradigm over 4, 13, 22 or 42 sessions, and in rats that experienced 22 sessions and were withdrawn from self-administration for a period of 4weeks. Four sessions of LgA methamphetamine enhanced proliferation and apoptosis and forty-two sessions of ShA and LgA methamphetamine reduced proliferation without effecting apoptosis. Withdrawal from twenty-two sessions of methamphetamine enhanced proliferation in LgA animals. Our findings demonstrate that proliferation of mPFC progenitors is vulnerable to psychostimulant exposure and withdrawal with distinct underlying mechanisms relating to methamphetamine toxicity. The susceptibility of mPFC progenitors to even modest doses of methamphetamine could account for the pronounced neuroadaptation in the mPFC linked to methamphetamine abuse.

  10. Low frequency pulsed electromagnetic field affects proliferation, tissue-specific gene expression, and cytokines release of human tendon cells.

    PubMed

    de Girolamo, L; Stanco, D; Galliera, E; Viganò, M; Colombini, A; Setti, S; Vianello, E; Corsi Romanelli, M M; Sansone, V

    2013-07-01

    Low frequency pulsed electromagnetic field (PEMF) has proven to be effective in the modulation of bone and cartilage tissue functional responsiveness, but its effect on tendon tissue and tendon cells (TCs) is still underinvestigated. PEMF treatment (1.5 mT, 75 Hz) was assessed on primary TCs, harvested from semitendinosus and gracilis tendons of eight patients, under different experimental conditions (4, 8, 12 h). Quantitative PCR analyses were conducted to identify the possible effect of PEMF on tendon-specific gene transcription (scleraxis, SCX and type I collagen, COL1A1); the release of pro- and anti-inflammatory cytokines and of vascular endothelial growth factor (VEGF) was also assessed. Our findings show that PEMF exposure is not cytotoxic and is able to stimulate TCs' proliferation. The increase of SCX and COL1A1 in PEMF-treated cells was positively correlated to the treatment length. The release of anti-inflammatory cytokines in TCs treated with PEMF for 8 and 12 h was significantly higher in comparison with untreated cells, while the production of pro-inflammatory cytokines was not affected. A dramatically higher increase of VEGF-A mRNA transcription and of its related protein was observed after PEMF exposure. Our data demonstrated that PEMF positively influence, in a dose-dependent manner, the proliferation, tendon-specific marker expression, and release of anti-inflammatory cytokines and angiogenic factor in a healthy human TCs culture model.

  11. Peroxisome proliferator-activated receptor gamma activators affect the maturation of human monocyte-derived dendritic cells.

    PubMed

    Gosset, P; Charbonnier, A S; Delerive, P; Fontaine, J; Staels, B; Pestel, J; Tonnel, A B; Trottein, F

    2001-10-01

    Peroxisome proliferator-activated receptor gamma (PPARgamma ), a member of the nuclear receptor superfamily, has recently been described as a modulator of macrophage functions and as an inhibitor of T cell proliferation. Here, we investigated the role of PPARgamma in dendritic cells (DC), the most potent antigen-presenting cells. We showed that PPARgamma is highly expressed in immature human monocyte-derived DC (MDDC) and that it may affect the immunostimulatory function of MDDC stimulated with lipopolysaccharide (LPS) or via CD40 ligand (CD40L). We found that the synthetic PPARgamma agonist rosiglitazone (as well as pioglitazone and troglitazone) significantly increases on LPS- and CD40L-activated MDDC, the surface expression of CD36 (by 184% and 104%, respectively) and CD86 (by 54% and 48%), whereas it reduces the synthesis of CD80 (by 42% and 42%). Moreover, activation of PPARgamma resulted in a dramatic decreased secretion of the Th1-promoting factor IL-12 in LPS- and CD40L-stimulated cells (by 47% and 62%), while the production of IL-1beta, TNF-alpha, IL-6 and IL-10 was unaffected. Finally, PPARgamma ligands down-modulate the synthesis of IFN-gamma -inducible protein-10 (recently termed as CXCL10) and RANTES (CCL5), both chemokines involved in the recruitment of Th1 lymphocytes (by 49% and 30%), but not the levels of the Th2 cell-attracting chemokines,macrophage-derived chemokine (CCL22) and thymus and activation regulated chemokine (CCL17), in mature MDDC. Taken together, our data suggest that activation of PPARgamma in human DC may have an impact in the orientation of primary and secondary immune responses by favoring type 2 responses.

  12. Methylmercury Exposure during Early Xenopus laevis Development Affects Cell Proliferation and Death but not Neural Progenitor Specification

    PubMed Central

    Huyck, Ryan W.; Nagarkar, Maitreyi; Olsen, Nina; Clamons, Samuel E.; Saha, Margaret S.

    2015-01-01

    Methylmercury (MeHg) is a widespread environmental toxin that preferentially and adversely affects developing organisms. To investigate the impact of MeHg toxicity on the formation of the vertebrate nervous system at physiologically relevant concentrations, we designed a graded phenotype scale for evaluating Xenopus laevis embryos exposed to MeHg in solution. Embryos displayed a range of abnormalities in response to MeHg, particularly in brain development, which is influenced by both MeHg concentration and the number of embryos per ml of exposure solution. A TC50 of ~50 μg/l and LC50 of ~100 μg/l were found when maintaining embryos at a density of one per ml, and both increased with increasing embryo density. In situ hybridization and microarray analysis showed no significant change in expression of early neural patterning genes including sox2, en2, or delta; however a noticeable decrease was observed in the terminal neural differentiation genes GAD and xGAT, but not xVGlut. PCNA, a marker for proliferating cells, was negatively correlated with MeHg dose, with a significant reduction in cell number in the forebrain and spinal cord of exposed embryos by tadpole stages. Conversely, the number of apoptotic cells in neural regions detected by a TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay was significantly increased. These results provide evidence that disruption of embryonic neural development by MeHg may not be directly due to a loss of neural progenitor specification and gene transcription, but to a more general decrease in cell proliferation and increase in cell death throughout the developing nervous system. PMID:25496965

  13. How does the supernatant of Lactobacillus acidophilus affect the proliferation and differentiation activities of rat bone marrow-derived stromal cells?

    PubMed

    Samadikuchaksaraei, A; Gholipourmalekabadi, M; Saberian, M; Abdollahpour Alitappeh, M; Shahidi Delshad, E

    2016-08-31

    Low proliferation rate and unwanted differentiation of bone marrow-derived stromal cells (rBMSCs) during the frequent passages have limited the use of such cells in clinical cell therapy. Recently, the researchers have focused on the effects of the components produced by some bacteria on proliferation of the stem cells. In this study, we discussed the possible effects of the Lactobacillus acidophilus supernatant on proliferation and differentiation of the rBMSCs. For this aim, the cells were isolated from rat bone marrow, characterized by culturing on tissue specific differentiation media and stained. The cells (passage two) were treated with different concentrations of the L. acidophilus supernatant (0, 0.1, 0.3, 0.9, 3, 9 and 30 &mgr;l/ml) for 14 days. The proliferation and differentiation capacity of the cells were then determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT assay) and tissue specific staining. The results showed a positive effect of the supernatant on the cell proliferation in 3 and 9 &mgr;l/ml concentrations, while did not affect the differentiation capacity of the rBMSCs. The current study strongly suggests the L. acidophilus supernatant as an alternative material that could be added to the media with aim of improvement in the proliferation rate of the rBMSCs without affecting their differentiation capacity.

  14. Thioredoxin (Trxo1) interacts with proliferating cell nuclear antigen (PCNA) and its overexpression affects the growth of tobacco cell culture.

    PubMed

    Calderón, Aingeru; Ortiz-Espín, Ana; Iglesias-Fernández, Raquel; Carbonero, Pilar; Pallardó, Federico Vicente; Sevilla, Francisca; Jiménez, Ana

    2017-04-01

    Thioredoxins (Trxs), key components of cellular redox regulation, act by controlling the redox status of many target proteins, and have been shown to play an essential role in cell survival and growth. The presence of a Trx system in the nucleus has received little attention in plants, and the nuclear targets of plant Trxs have not been conclusively identified. Thus, very little is known about the function of Trxs in this cellular compartment. Previously, we studied the intracellular localization of PsTrxo1 and confirmed its presence in mitochondria and, interestingly, in the nucleus under standard growth conditions. In investigating the nuclear function of PsTrxo1 we identified proliferating cellular nuclear antigen (PCNA) as a PsTrxo1 target by means of affinity chromatography techniques using purified nuclei from pea leaves. Such protein-protein interaction was corroborated by dot-blot and bimolecular fluorescence complementation (BiFC) assays, which showed that both proteins interact in the nucleus. Moreover, PsTrxo1 showed disulfide reductase activity on previously oxidized recombinant PCNA protein. In parallel, we studied the effects of PsTrxo1 overexpression on Tobacco Bright Yellow-2 (TBY-2) cell cultures. Microscopy and flow-cytometry analysis showed that PsTrxo1 overexpression increases the rate of cell proliferation in the transformed lines, with a higher percentage of the S phase of the cell cycle at the beginning of the cell culture (days 1 and 3) and at the G2/M phase after longer times of culture (day 9), coinciding with an upregulation of PCNA protein. Furthermore, in PsTrxo1 overexpressed cells there is a decrease in the total cellular glutathione content but maintained nuclear GSH accumulation, especially at the end of the culture, which is accompanied by a higher mitotic index, unlike non-overexpressing cells. These results suggest that Trxo1 is involved in the cell cycle progression of TBY-2 cultures, possibly through its link with cellular PCNA

  15. Antagonic activities of Trypanosoma cruzi metacaspases affect the balance between cell proliferation, death and differentiation.

    PubMed

    Laverrière, M; Cazzulo, J J; Alvarez, V E

    2012-08-01

    Metacaspases are distant relatives of animal caspases present in plants, fungi and protozoa. At variance with caspases, metacaspases exhibit stringent specificity for basic amino-acid residues and are absolutely dependent on millimolar concentrations of calcium. In the protozoan parasite Trypanosoma cruzi, metacaspases have been suggested to be involved in an apoptosis-like phenomenon upon exposure of the parasite to fresh human serum (FHS). Nuclear relocalization of metacaspases was observed after FHS treatment and overexpression of metacaspase-5 led to enhanced sensitivity to this stimulus. Here we report some biochemical properties of T. cruzi metacaspases. Performing fluorescent-activated cell sorting (FACS) analysis of epimastigotes inducibly overexpressing metacaspase-3, we demonstrate a role for this metacaspase in cell cycle progression, protection of epimastigotes from naturally occurring cell death and differentiation to infective metacyclic trypomastigotes. We also show that regulation of metacaspase-3 activity is important for cell cycle completion inside the mammalian host. On the other hand, inducible overexpression of metacaspase-5 lacking its C-terminal domain caused an apoptotic-like response. These results suggest that the two T. cruzi metacaspases could play an important role in the life cycle and bring to light the close relationship between cell division, death and differentiation in this ancient unicellular eukaryote.

  16. Synthetic conjugates of genistein affecting proliferation and mitosis of cancer cells.

    PubMed

    Rusin, Aleksandra; Zawisza-Puchałka, Jadwiga; Kujawa, Katarzyna; Gogler-Pigłowska, Agnieszka; Wietrzyk, Joanna; Switalska, Marta; Głowala-Kosińska, Magdalena; Gruca, Aleksandra; Szeja, Wiesław; Krawczyk, Zdzisław; Grynkiewicz, Grzegorz

    2011-01-01

    This paper describes the synthesis and antiproliferative activity of conjugates of genistein (1) and unsaturated pyranosides. Constructs linking genistein with a sugar moiety through an alkyl chain were obtained in a two-step synthesis: in a first step genistein was converted into an intermediate bearing an ω-hydroxyalkyl substituent, containing two, three or five carbon atoms, at position 7, while the second step involved Ferrier glycosylation reaction, employing glycals. Antiproliferative activity of several genistein derivatives was tested in cancer cell lines in vitro. The most potent derivative, Ram-3 inhibited the cell cycle, interacted with mitotic spindles and caused apoptotic cell death. Neither genistein nor the sugar alone were able to influence the mitotic spindle organization. Our results indicate, that conjugation of genistein with certain sugars may render the interaction of derivatives with new molecular targets.

  17. Aptamer targeting EGFRvIII mutant hampers its constitutive autophosphorylation and affects migration, invasion and proliferation of glioblastoma cells

    PubMed Central

    Camorani, Simona; Crescenzi, Elvira; Colecchia, David; Carpentieri, Andrea; Amoresano, Angela; Fedele, Monica; Chiariello, Mario; Cerchia, Laura

    2015-01-01

    Glioblastoma Multiforme (GBM) is the most common and aggressive human brain tumor, associated with very poor survival despite surgery, radiotherapy and chemotherapy. The epidermal growth factor receptor (EGFR) and the platelet-derived growth factor receptor β (PDGFRβ) are hallmarks in GBM with driving roles in tumor progression. In approximately half of the tumors with amplified EGFR, the EGFRvIII truncated extracellular mutant is detected. EGFRvIII does not bind ligands, is highly oncogenic and its expression confers resistance to EGFR tyrosine kinase inhibitors (TKIs). It has been demonstrated that EGFRvIII-dependent cancers may escape targeted therapy by developing dependence on PDGFRβ signaling, thus providing a strong rationale for combination therapy aimed at blocking both EGFRvIII and PDGFRβ signaling. We have recently generated two nuclease resistant RNA aptamers, CL4 and Gint4.T, as high affinity ligands and inhibitors of the human wild-type EGFR (EGFRwt) and PDGFRβ, respectively. Herein, by different approaches, we demonstrate that CL4 aptamer binds to the EGFRvIII mutant even though it lacks most of the extracellular domain. As a consequence of binding, the aptamer inhibits EGFRvIII autophosphorylation and downstream signaling pathways, thus affecting migration, invasion and proliferation of EGFRvIII-expressing GBM cell lines. Further, we show that targeting EGFRvIII by CL4, as well as by EGFR-TKIs, erlotinib and gefitinib, causes upregulation of PDGFRβ. Importantly, CL4 and gefitinib cooperate with the anti-PDGFRβ Gint4.T aptamer in inhibiting cell proliferation. The proposed aptamer-based strategy could have impact on targeted molecular cancer therapies and may result in progresses against GBMs. PMID:26461476

  18. Estradiol and GPER Activation Differentially Affect Cell Proliferation but Not GPER Expression in the Hippocampus of Adult Female Rats

    PubMed Central

    Duarte-Guterman, Paula; Lieblich, Stephanie E.; Chow, Carmen; Galea, Liisa A. M.

    2015-01-01

    Estradiol increases cell proliferation in the dentate gyrus of the female rodent but it is not known whether the G protein-coupled estrogen receptor (GPER), a membrane receptor, is involved in this process, nor whether there are regional differences in estradiol’s effects on cell proliferation. Thus, we investigated whether estradiol exerts its effects on cell proliferation in the dorsal and ventral dentate gyrus through GPER, using the GPER agonist, G1, and antagonist, G15. Ovariectomized adult female rats received a single injection of either: 17β-estradiol (10 μg), G1 (0.1, 5, 10 μg), G15 (40 μg), G15 and estradiol, or vehicle (oil, DMSO, or oil+DMSO). After 30 min, animals received an injection of bromodeoxyuridine (BrdU) and were perfused 24 h later. Acute treatment with estradiol increased, while the GPER agonist G1 (5 μg) decreased, the number of BrdU+ cells in the dentate gyrus relative to controls. The GPER antagonist, G15 increased the number of BrdU+ cells relative to control in the dorsal region and decreased the number of BrdU+ cells in the ventral region. However, G15 treatment in conjunction with estradiol partially eliminated the estradiol-induced increase in cell proliferation in the dorsal dentate gyrus. Furthermore, G1 decreased the expression of GPER in the dentate gyrus but not the CA1 and CA3 regions of the hippocampus. In summary, we found that activation of GPER decreased cell proliferation and GPER expression in the dentate gyrus of young female rats, presenting a potential and novel estrogen-independent role for this receptor in the adult hippocampus. PMID:26075609

  19. Estradiol and GPER Activation Differentially Affect Cell Proliferation but Not GPER Expression in the Hippocampus of Adult Female Rats.

    PubMed

    Duarte-Guterman, Paula; Lieblich, Stephanie E; Chow, Carmen; Galea, Liisa A M

    2015-01-01

    Estradiol increases cell proliferation in the dentate gyrus of the female rodent but it is not known whether the G protein-coupled estrogen receptor (GPER), a membrane receptor, is involved in this process, nor whether there are regional differences in estradiol's effects on cell proliferation. Thus, we investigated whether estradiol exerts its effects on cell proliferation in the dorsal and ventral dentate gyrus through GPER, using the GPER agonist, G1, and antagonist, G15. Ovariectomized adult female rats received a single injection of either: 17β-estradiol (10 μg), G1 (0.1, 5, 10 μg), G15 (40 μg), G15 and estradiol, or vehicle (oil, DMSO, or oil+DMSO). After 30 min, animals received an injection of bromodeoxyuridine (BrdU) and were perfused 24 h later. Acute treatment with estradiol increased, while the GPER agonist G1 (5 μg) decreased, the number of BrdU+ cells in the dentate gyrus relative to controls. The GPER antagonist, G15 increased the number of BrdU+ cells relative to control in the dorsal region and decreased the number of BrdU+ cells in the ventral region. However, G15 treatment in conjunction with estradiol partially eliminated the estradiol-induced increase in cell proliferation in the dorsal dentate gyrus. Furthermore, G1 decreased the expression of GPER in the dentate gyrus but not the CA1 and CA3 regions of the hippocampus. In summary, we found that activation of GPER decreased cell proliferation and GPER expression in the dentate gyrus of young female rats, presenting a potential and novel estrogen-independent role for this receptor in the adult hippocampus.

  20. Tumor suppressor KAI1 affects integrin {alpha}v{beta}3-mediated ovarian cancer cell adhesion, motility, and proliferation

    SciTech Connect

    Ruseva, Zlatna; Geiger, Pamina Xenia Charlotte; Hutzler, Peter; Kotzsch, Matthias; Luber, Birgit; Schmitt, Manfred; Gross, Eva; Reuning, Ute

    2009-06-10

    The tetraspanin KAI1 had been described as a metastasis suppressor in many different cancer types, a function for which associations of KAI1 with adhesion and signaling receptors of the integrin superfamily likely play a role. In ovarian cancer, integrin {alpha}v{beta}3 correlates with tumor progression and its elevation in vitro provoked enhanced cell adhesion accompanied by significant increases in cell motility and proliferation in the presence of its major ligand vitronectin. In the present study, we characterized integrin {alpha}v{beta}3-mediated tumor biological effects as a function of cellular KAI1 restoration and proved for the first time that KAI1, besides its already known physical crosstalk with {beta}1-integrins, also colocalizes with integrin {alpha}v{beta}3. Functionally, elevated KAI1 levels drastically increased integrin {alpha}v{beta}3/vitronectin-dependent ovarian cancer cell adhesion. Since an intermediate level of cell adhesive strength is required for optimal cell migration, we next studied ovarian cancer cell motility as a function of KAI1 restoration. By time lapse video microscopy, we found impaired integrin {alpha}v{beta}3/vitronectin-mediated cell migration most probably due to strongly enhanced cellular immobilization onto the adhesion-supporting matrix. Moreover, KAI1 reexpression significantly diminished cell proliferation. These data strongly indicate that KAI1 may suppress ovarian cancer progression by inhibiting integrin {alpha}v{beta}3/vitronectin-provoked tumor cell motility and proliferation as important hallmarks of the oncogenic process.

  1. Xanthosine administration does not affect the proportion of epithelial stem cells in bovine mammary tissue, but has a latent negative effect on cell proliferation

    SciTech Connect

    Rauner, Gat; Barash, Itamar

    2014-10-15

    The challenge in manipulating the proportion of somatic stem cells lies in having to override tissue homeostasis. Xanthosine infusion via the teat canal has been reported to augment the number of label-retaining cells in the mammary gland of 3-month-old bovine calves. To further delineate xanthosine's effect on defined stem cells in the mammary gland of heifers—which are candidates for increased prospective milk production following such manipulation—bovine mammary parenchymal tissue was transplanted and integrated into the cleared mammary fat pad of immunodeficient mice. Xanthosine administration for 14 days did not affect the number of label-retaining cells after 10- and 11-week chases. No change in stem cell proportion, analyzed according to CD49f and CD24 expression, was noted. Clone formation and propagation rate of cultured cells, as well as expression of stem cell markers, were also unaffected. In contrast, a latent 50% decrease in bovine mammary cell proliferation rate was observed 11 weeks after xanthosine administration. Tumor development in mice was also limited by xanthosine administration. These effects may have resulted from an initial decrease in expression of the rate-limiting enzyme in guanine synthesis, IMPDH. The data indicate that caution should be exerted when considering xanthosine for stem cell manipulation. - Highlights: • Novel “bovinized“ mouse model for exogenous effects on bovine mammary gland. • Xanthosine did not affect stem cell number/function in bovine mammary gland. • Xanthosine caused an immediate decrease in IMPDH expression in bovine mammary gland. • Xanthosine had latent negative effect on cell proliferation in bovine mammary gland. • Xanthosine administration limited mammary tumor growth.

  2. Apatite formation on bioactive calcium-silicate cements for dentistry affects surface topography and human marrow stromal cells proliferation.

    PubMed

    Gandolfi, Maria Giovanna; Ciapetti, Gabriela; Taddei, Paola; Perut, Francesca; Tinti, Anna; Cardoso, Marcio Vivan; Van Meerbeek, Bart; Prati, Carlo

    2010-10-01

    The effect of ageing in phosphate-containing solution of bioactive calcium-silicate cements on the chemistry, morphology and topography of the surface, as well as on in vitro human marrow stromal cells viability and proliferation was investigated. A calcium-silicate cement (wTC) mainly based on dicalcium-silicate and tricalcium-silicate was prepared. Alpha-TCP was added to wTC to obtain wTC-TCP. Bismuth oxide was inserted in wTC to prepare a radiopaque cement (wTC-Bi). A commercial calcium-silicate cement (ProRoot MTA) was tested as control. Cement disks were aged in DPBS for 5 h ('fresh samples'), 14 and 28 days, and analyzed by ESEM/EDX, SEM/EDX, ATR-FTIR, micro-Raman techniques and scanning white-light interferometry. Proliferation, LDH release, ALP activity and collagen production of human marrow stromal cells (MSC) seeded for 1-28 days on the cements were evaluated. Fresh samples exposed a surface mainly composed of calcium-silicate hydrates CSH (from the hydration of belite and alite), calcium hydroxide, calcium carbonate, and ettringite. Apatite nano-spherulites rapidly precipitated on cement surfaces within 5 h. On wTC-TCP the Ca-P deposits appeared thicker than on the other cements. Aged cements showed an irregular porous calcium-phosphate (Ca-P) coating, formed by aggregated apatite spherulites with interspersed calcite crystals. All the experimental cements exerted no acute toxicity in the cell assay system and allowed cell growth. Using biochemical results, the scores were: fresh cements>aged cements for cell proliferation and ALP activity (except for wTC-Bi), whereas fresh cementscell proliferation than aged cements, probably favoured by the presence of Si-OH gel and the early formation of apatite nano-spherulites; (2) the alpha-TCP doped cement aged for 28 days displayed the highest bioactivity and cell proliferation; (3) the deleterious effect of bismuth on cell

  3. Hyper-O-GlcNAcylation of YB-1 affects Ser102 phosphorylation and promotes cell proliferation in hepatocellular carcinoma.

    PubMed

    Liu, Qingqing; Tao, Tao; Liu, Fang; Ni, Runzhou; Lu, Cuihua; Shen, Aiguo

    2016-12-10

    As an essential post-translational modification, O-GlcNAcylation has been thought to be able to modulate various nuclear and cytoplasmic proteins and is emerging as a key regulator of multiple biological processes, such as transcription, cell growth, signal transduction, and cell motility. Recently, authoritative glycomics analyses have reported extensive crosstalk between O-GlcNAcylation and phosphorylation, which always dynamically interplay with each other and regulate signaling, transcription, and other cellular processes. Also, plentiful studies have shown close correlation between YB-1 phosphorylation and tumorigenesis. Therefore, our study aimed to determine whether YB-1 was O-GlcNAc modified and whether such modification could interact with its phosphorylation during the process of HCC development. Western blot and immunohistochemistry were firstly conducted to reveal obvious up-regulation of YB-1, OGT and O-GlcNAc modification in HCC tissues. What is more, not only YB-1 was identified to be O-GlcNAcylated but hyper-O-GlcNAcylation was demonstrated to facilitate HCC cell proliferation in a YB-1 dependent manner. Moreover, we detected four specific O-GlcNAc sites and confirmed T126A to be the most effective mutant in HCC cell proliferation via close O-GlcNAcylation-phosphorylation interaction. Even more interestingly, we discovered that T126A-induced HCC cell retardation and subdued transcriptional activity of YB-1 could be partially reversed by T126A/S102E mutant. From all above, it is not difficult to find that glycosylated-YB-1 mainly enhanced cell proliferation through congenerous actions with YB-1 phosphorylation and thus played indispensable roles in fine-tuning cell proliferation and procession of HCC.

  4. AtLSG1-2 Regulates Leaf Growth by Affecting Cell Proliferation and the Onset of Endoreduplication and Synergistically Interacts with AtNMD3 during Cell Proliferation Process

    PubMed Central

    Zhao, Huayan; Lü, Shiyou; Xiong, Liming

    2017-01-01

    AtLSG1-2 is a circularly permuted GTPase required for ribosome biogenesis and recently shown to be involved in early leaf development, although it was unclear how AtLSG1-2 affects leaf growth. Here, we found that atlsg1-2 mutants had reduced leaf size as a result of decreased cell size and cell number. Leaf kinematic analysis and CYCB1;1::GUS expression pattern in atlsg1-2 mutant indicated that loss of function of AtLSG1-2 delays the transition from cell division to cell expansion. Decreases in ploidy levels and trichome branch number suggest that AtLSG1-2 deficiency suppresses endoreduplication. Real-time PCR analysis showed that genes specifically expressed in the proliferation stage were highly expressed and those involved in endoreduplication were differentially regulated. LSG1 is known to mediate the recruitment of nucleocytoplasmic shuttling protein NMD3 back to the nucleus in yeast, yet their relationship was unclear in plants. Our genetic analysis revealed that the atlsg1 atnmd3 double mutant displayed enhanced phenotypes as compared with the respective single mutant and that AtLSG1-2 and AtNMD3 synergistically affect the cell proliferation process. PMID:28344588

  5. CDC42 Gtpase Activation Affects Hela Cell DNA Repair and Proliferation Following UV Radiation-Induced Genotoxic Stress.

    PubMed

    Ascer, Liv G; Magalhaes, Yuli T; Espinha, Gisele; Osaki, Juliana H; Souza, Renan C; Forti, Fabio L

    2015-09-01

    Cell division control protein 42 (CDC42) homolog is a small Rho GTPase enzyme that participates in such processes as cell cycle progression, migration, polarity, adhesion, and transcription. Recent studies suggest that CDC42 is a potent tumor suppressor in different tissues and is related to aging processes. Although DNA damage is crucial in aging, a potential role for CDC42 in genotoxic stress remains to be explored. Migration, survival/proliferation and DNA damage/repair experiments were performed to demonstrate CDC42 involvement in the recovery of HeLa cells exposed to ultraviolet radiation-induced stress. Sub-lines of HeLa cells ectopically expressing the constitutively active CDC42-V12 mutant were generated to examine whether different CDC42-GTP backgrounds might reflect different sensitivities to UV radiation. Our results show that CDC42 constitutive activation does not interfere with HeLa cell migration after UV radiation. However, the minor DNA damage exhibited by the CDC42-V12 mutant exposed to UV radiation most likely results in cell cycle arrest at the G2/M checkpoint and reduced proliferation and survival. HeLa cells and Mock clones, which express endogenous wild-type CDC42 and show normal activity, are more resistant to UV radiation. None of these effects are altered by pharmacological CDC42 inhibition. Finally, the phosphorylation status of the DNA damage response proteins γ-H2AX and p-Chk1 was found to be delayed and attenuated, respectively, in CDC42-V12 clones. In conclusion, the sensitivity of HeLa cells to ultraviolet radiation increases with CDC42 over-activation due to inadequate DNA repair signaling, culminating in G2/M cell accumulation, which is translated into reduced cellular proliferation and survival.

  6. ERK2 protein regulates the proliferation of human mesenchymal stem cells without affecting their mobilization and differentiation potential

    SciTech Connect

    Carcamo-Orive, Ivan; Tejados, Naiara; Delgado, Jesus; Gaztelumendi, Ainhoa; Otaegui, David; Lang, Valerie; Trigueros, Cesar

    2008-05-01

    Human Mesenchymal Stem Cells (hMSC), derived mainly from adult bone marrow, are valuable models for the study of processes involved in stem cell self-renewal and differentiation. As the Extracellular signal-Regulated Kinase (ERK) signalling pathway is a major contributor to cellular growth, differentiation and survival, we have studied the functions of this kinase in hMSC activity. Ablation of ERK2 gene expression (but not ERK1) by RNA interference significantly reduced proliferation of hMSC. This reduction was due to a defect in Cyclin D1 expression and subsequent arrest in the G0/G1 phase of the cell cycle. hMSC growth is enhanced through culture medium supplementation with growth factors (GFs) such as Platelet-Derived Growth Factor (PDGF), basic Fibroblast Growth Factor (bFGF) or Epidermal Growth Factor (EGF). However, these supplements could not rescue the defect observed after ERK2 knockdown, suggesting a common signalling pathway used by these GFs for proliferation. In contrast, ERK1/2 may be dissociated from chemotactic signalling induced by the same GFs. Additionally, hMSCs were capable of differentiating into adipocytes even in the absence of either ERK1 or ERK2 proteins. Our data show that hMSCs do not require cell division to enter the adipogenic differentiation process, indicating that clonal amplification of these cells is not a critical step. However, cell-cell contact seems to be an essential requirement to be able to differentiate into mature adipocytes.

  7. A mixture of phytosterols from Dunaliella tertiolecta affects proliferation of peripheral blood mononuclear cells and cytokine production in sheep.

    PubMed

    Caroprese, Mariangela; Albenzio, Marzia; Ciliberti, Maria Giovanna; Francavilla, Matteo; Sevi, Agostino

    2012-11-15

    The aim of this study was to investigate the immunomodulatory and anti-inflammatory role of a mixture of phytosterols extracted from the microalga Dunaliella tertiolecta on peripheral blood mononuclear cells (PBMC) isolated from sheep. PBMC were treated to determine cell proliferation and cytokine production with different sterols: ergosterol (E), a mixture of eleven Algae sterols extracted and purified from D. tertiolecta (Algae Extract, AE), a mixture of ergosterol and 7-dehydroporiferasterol extracted and purified from D. tertiolecta (Purified Extract, PE). Cytokine production (TNF-α, IL-6, IL-1β, and IL-10) was evaluated after cell treatment with Concanavalin A (Con A) and lipopolysaccharide (LPS). The mixture of ergosterol and 7-dehydroporiferasterol extracted and purified from D. tertiolecta showed a suppressive effect on cell proliferation, and a reduction of pro-inflammatory cytokines production. Furthermore, a stimulatory effect on the production of the regulatory cytokine IL-10 was found. The immunosuppressive effect exerted by the mixture of ergosterol and 7-dehydroporiferasterol from D. tertiolecta was dose-dependent both in suppressing cell proliferation and in stimulating IL-10 production. Present results showed that the immunomodulatory and anti-inflammatory activities were more apparent in the purified extract characterized by the mixture of ergosterol and 7-dehydroporiferasterol, and might depend on the existence of a synergic effect of the structures of the two phytosterols. Furthermore, findings from our study suggest that the purified extract characterized by the mixture of ergosterol and 7-dehydroporiferasterol from D. tertiolecta could be used to reduce immune reactions resulting from inflammatory diseases in sheep production systems, and could have innovative implications on the modulation of sheep immune system when used as feed supplements.

  8. The CCL2/CCR2 Axis Affects Transmigration and Proliferation but Not Resistance to Chemotherapy of Acute Myeloid Leukemia Cells

    PubMed Central

    Macanas-Pirard, Patricia; Quezada, Thomas; Navarrete, Leonardo; Broekhuizen, Richard; Leisewitz, Andrea; Nervi, Bruno; Ramírez, Pablo A.

    2017-01-01

    Acute myeloid leukemia (AML) has a high mortality rate despite chemotherapy and transplantation. Both CXCR4/SDF-1 and VLA-4/VCAM1 axes are involved in leukemia protection but little is known about the role of CCL2/CCR2 in AML biology and protection against chemotherapy. We measured CCR2 expression in AML cell lines and primary AML cells by flow cytometry (FCM), real time PCR (RT-PCR) and western blot (WB). CCL2 production was quantified by solid phase ELISA in peripheral blood (PB) and bone marrow (BM) serum. We measured chemotaxis in a transwell system with different concentrations of CCL2/CCR2 blockers; cell cycle with BrDU and propidium iodide and proliferation with yellow tetrazolium MTT. We determined synergy in in vitro cell apoptosis combining chemotherapy and CCL2/CCR2 blockade. Finally, we performed chemoprotection studies in an in vivo mouse model. Of 35 patients, 23 (65%) expressed CCR2 by FCM in PB. Two cell lines expressed high levels of CCR2 (THP-1 and murine AML). RT-PCR and WB confirmed CCR2 production. CCL2 solid phase ELISA showed significantly lower levels of CCL2 in PB and BM compared to normal controls. Chemotaxis experiments confirmed a dose-dependent migration in AML primary cells expressing CCR2 and THP-1 cells. A significant inhibition of transmigration was seen after CCL2/CCR2 blockade. Proliferation of CCR2+ AML cell lines was slightly increased (1.4-fold) after axis stimulation. We observed a non-significant increase in phase S THP-1 cells exposed to CCL2 and a concomitant decrease of cells in G1. The chemotherapy studies did not show a protective effect of CCL2 on cytarabine-induced apoptosis or synergy with chemotherapy after CCL2/CCR2 blockade both in vitro and in vivo. In conclusion, CCL2/CCR2 axis is expressed in the majority of monocytoid AML blasts. The axis is involved in cell trafficking and proliferation but no in vitro and in vivo chemotherapy protective effect was seen. PMID:28045930

  9. P120-catenin isoforms 1A and 3A differently affect invasion and proliferation of lung cancer cells

    SciTech Connect

    Liu Yang; Dong Qianze; Zhao Yue; Dong Xinjun; Miao Yuan; Dai Shundong; Yang Zhiqiang; Zhang Di; Wang Yan; Li Qingchang; Zhao Chen; Wang Enhua

    2009-03-10

    Different isoforms of p120-catenin (p120ctn), a member of the Armadillo gene family, are variably expressed in different tissues as a result of alternative splicing and the use of multiple translation initiation codons. When expressed in cancer cells, these isoforms may confer different properties with respect to cell adhesion and invasion. We have previously reported that the p120ctn isoforms 1 and 3 were the most highly expressed isoforms in normal lung tissues, and their expression level was reduced in lung tumor cells. To precisely define their biological roles, we transfected p120ctn isoforms 1A and 3A into the lung cancer cell lines A549 and NCI-H460. Enhanced expression of p120ctn isoform 1A not only upregulated E-cadherin and {beta}-catenin, but also downregulated the Rac1 activity, and as a result, inhibited the ability of cells to invade. In contrast, overexpression of p120ctn isoform 3A led to the inactivation of Cdc42 and the activation of RhoA, and had a smaller influence on invasion. However, we found that isoform 3A had a greater ability than isoform 1A in both inhibiting the cell cycle and reducing tumor cell proliferation. The present study revealed that p120ctn isoforms 1A and 3A differently regulated the adhesive, proliferative, and invasive properties of lung cancer cells through distinct mechanisms.

  10. Acyl-coenzyme A: cholesterol acyltransferase inhibitor Avasimibe affect survival and proliferation of glioma tumor cell lines.

    PubMed

    Bemlih, Sana; Poirier, Marie-Denise; El Andaloussi, Abdeljabar

    2010-06-15

    Glioblastoma is the most common primary brain tumor in adults and one of its hallmarks is resistance to apoptosis. Acyl-CoA: cholesterol acyltransferase (ACAT) is an intracellular membrane-bound enzyme that uses cholesterol and long chain fatty acyl-CoA as substrates to produce cholesteryl esters. The presence of cholesteryl esters in glioblastoma may be related to vascular and/or cell neoplastic proliferation in the tumor mass, two prerequisites for tumor cell growth. ACAT activity has been detected in glioblastoma cell homogenates. The present study is the first report on the effect of Avasimibe, a specific inhibitor of ACAT, on glioma cell lines (U87, A172 and GL261). Our results showed that Avasimibe inhibited ACAT-1 expression and cholesterol ester synthesis in glioma cell lines. Moreover, Avasimibe inhibited the growth of the cells by inducing cell cycle arrest and induced apoptosis as a result of caspase-8 and caspase-3 activation. Also, Our findings provide proof of principle that targeting ACAT-1 with the inhibitor Avasimibe could be an efficient therapy in the treatment of glioblastoma.

  11. MicroRNA-199a is induced in dystrophic muscle and affects WNT signaling, cell proliferation, and myogenic differentiation

    PubMed Central

    Alexander, M S; Kawahara, G; Motohashi, N; Casar, J C; Eisenberg, I; Myers, J A; Gasperini, M J; Estrella, E A; Kho, A T; Mitsuhashi, S; Shapiro, F; Kang, P B; Kunkel, L M

    2013-01-01

    In patients with Duchenne muscular dystrophy (DMD), the absence of a functional dystrophin protein results in sarcolemmal instability, abnormal calcium signaling, cardiomyopathy, and skeletal muscle degeneration. Using the dystrophin-deficient sapje zebrafish model, we have identified microRNAs (miRNAs) that, in comparison to our previous findings in human DMD muscle biopsies, are uniquely dysregulated in dystrophic muscle across vertebrate species. MiR-199a-5p is dysregulated in dystrophin-deficient zebrafish, mdx5cv mice, and human muscle biopsies. MiR-199a-5p mature miRNA sequences are transcribed from stem loop precursor miRNAs that are found within the introns of the dynamin-2 and dynamin-3 loci. The miR-199a-2 stem loop precursor transcript that gives rise to the miR-199a-5p mature transcript was found to be elevated in human dystrophic muscle. The levels of expression of miR-199a-5p are regulated in a serum response factor (SRF)-dependent manner along with myocardin-related transcription factors. Inhibition of SRF-signaling reduces miR-199a-5p transcript levels during myogenic differentiation. Manipulation of miR-199a-5p expression in human primary myoblasts and myotubes resulted in dramatic changes in cellular size, proliferation, and differentiation. MiR-199a-5p targets several myogenic cell proliferation and differentiation regulatory factors within the WNT signaling pathway, including FZD4, JAG1, and WNT2. Overexpression of miR-199a-5p in the muscles of transgenic zebrafish resulted in abnormal myofiber disruption and sarcolemmal membrane detachment, pericardial edema, and lethality. Together, these studies identify miR-199a-5p as a potential regulator of myogenesis through suppression of WNT-signaling factors that act to balance myogenic cell proliferation and differentiation. PMID:23764775

  12. MicroRNA-199a is induced in dystrophic muscle and affects WNT signaling, cell proliferation, and myogenic differentiation.

    PubMed

    Alexander, M S; Kawahara, G; Motohashi, N; Casar, J C; Eisenberg, I; Myers, J A; Gasperini, M J; Estrella, E A; Kho, A T; Mitsuhashi, S; Shapiro, F; Kang, P B; Kunkel, L M

    2013-09-01

    In patients with Duchenne muscular dystrophy (DMD), the absence of a functional dystrophin protein results in sarcolemmal instability, abnormal calcium signaling, cardiomyopathy, and skeletal muscle degeneration. Using the dystrophin-deficient sapje zebrafish model, we have identified microRNAs (miRNAs) that, in comparison to our previous findings in human DMD muscle biopsies, are uniquely dysregulated in dystrophic muscle across vertebrate species. MiR-199a-5p is dysregulated in dystrophin-deficient zebrafish, mdx(5cv) mice, and human muscle biopsies. MiR-199a-5p mature miRNA sequences are transcribed from stem loop precursor miRNAs that are found within the introns of the dynamin-2 and dynamin-3 loci. The miR-199a-2 stem loop precursor transcript that gives rise to the miR-199a-5p mature transcript was found to be elevated in human dystrophic muscle. The levels of expression of miR-199a-5p are regulated in a serum response factor (SRF)-dependent manner along with myocardin-related transcription factors. Inhibition of SRF-signaling reduces miR-199a-5p transcript levels during myogenic differentiation. Manipulation of miR-199a-5p expression in human primary myoblasts and myotubes resulted in dramatic changes in cellular size, proliferation, and differentiation. MiR-199a-5p targets several myogenic cell proliferation and differentiation regulatory factors within the WNT signaling pathway, including FZD4, JAG1, and WNT2. Overexpression of miR-199a-5p in the muscles of transgenic zebrafish resulted in abnormal myofiber disruption and sarcolemmal membrane detachment, pericardial edema, and lethality. Together, these studies identify miR-199a-5p as a potential regulator of myogenesis through suppression of WNT-signaling factors that act to balance myogenic cell proliferation and differentiation.

  13. PU.1 affects proliferation of the human acute myeloid leukemia U937 cell line by directly regulating MEIS1

    PubMed Central

    ZHOU, JING; ZHANG, XIAOFENG; WANG, YUHUA; GUAN, YINGHUI

    2015-01-01

    The transcription factor PU.1 is a member of the ETS family, which is expressed in a wide variety of hematopoietic lineages. Accumulating evidence has indicated that PU.1 plays a key role in hematopoiesis, and reduced expression of PU.1 leads to the pathogenesis of human myeloid leukemia. As a multi-functional factor, PU.1 is also required for mixed lineage leukemia (MLL) stem cell potential and the development of MLL. However, the function of PU.1 in human non-MLL leukemia and its molecular mechanism remains poorly understood. In the present study, PU.1 siRNA was demonstrated to efficiently inhibit the transcription level of oncogene MEIS1 in the human acute myeloid non-MLL leukemia U937 cell line. In addition, PU.1, as a positive regulator of MEIS1, performed a crucial role in maintaining cell proliferation. Using electrophoretic mobility shift assay, chromatin immunoprecipitation analysis and luciferase reporter assay, previously unexplored evidence that PU.1 activated the MEIS1 promoter through a conserved binding motif in vitro and in vivo was further defined. Overall, the present study provides insight into the molecular mechanism of the contribution of PU.1 to the pathogenesis of non-MLL U937 cells, which is mediated by direct regulation of MEIS1 transcription. The present data reveal the possibility of developing an alternative therapy for non-MLL leukemia by targeting PU.1-mediated MEIS1 gene activation. PMID:26622774

  14. MicroRNA138 regulates keratin 17 protein expression to affect HaCaT cell proliferation and apoptosis by targeting hTERT in psoriasis vulgaris.

    PubMed

    Feng, Shi-Jun; Chu, Rui-Qi; Ma, Jing; Wang, Zheng-Xiang; Zhang, Guang-Jing; Yang, Xiu-Fang; Song, Zhi; Ma, Yun-Yi

    2017-01-01

    The purpose of this study is to explore the how microRNA-138 (miR-138) affects the expression of keratin 17 (K17) and psoriasis development. Twenty-eight skin lesions from patients with psoriasis vulgaris and twenty-four normal skin tissues from healthy controls were collected. The HaCaT cells were assigned into blank, negative control (NC), miR-138 mimic, miR-138 inhibitor, hTERT siRNA and miR-138 inhibitor+hTERT siRNA groups. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the miR-138 expression. The hTERT and K17 protein expression were testified by Western Blotting. MTT assay, flow cytometry with PI single staining and Annexin V/PI double staining were performed to detect the cell proliferation activity, cell cycle and apoptosis, respectively. Compared with the healthy skin, the expression of miR-138 decreased in the psoriatic skin, but hTERT and K17 protein expressions increased. The miR-138 mimic and hTERT siRNA groups showed significantly decreased hTERT and K17 protein expressions, inhibited cell proliferation, increased number of cells at G1 phase and elevated apoptosis rate in comparison to the rest three groups. The hTERT and K17 protein expressions in the miR-138 inhibitor group were up-regulated with promoted cell proliferation and reduced apoptosis rate as compared with the other four groups. In the miR-138 inhibitor+hTERT siRNA group, the hTERT and K17 protein expressions, cell proliferation and apoptosis were intermediate between the miR-138 inhibitor and hTERT siRNA groups. These findings indicated that the expression of miR-138 was lower in the psoriatic skin, which was negatively correlated to K17 expression. MiR-138 may regulate K17 protein expression to affect HaCaT cell proliferation and apoptosis by targeting hTERT gene.

  15. Acrylamide affects proliferation and differentiation of the neural progenitor cell line C17.2 and the neuroblastoma cell line SH-SY5Y.

    PubMed

    Attoff, K; Kertika, D; Lundqvist, J; Oredsson, S; Forsby, A

    2016-09-01

    Acrylamide is a well-known neurotoxic compound and people get exposed to the compound by food consumption and environmental pollutants. Since acrylamide crosses the placenta barrier, the fetus is also being exposed resulting in a risk for developmental neurotoxicity. In this study, the neural progenitor cell line C17.2 and the neuroblastoma cell line SH-SY5Y were used to study proliferation and differentiation as alerting indicators for developmental neurotoxicity. For both cell lines, acrylamide reduced the number of viable cells by reducing proliferation and inducing cell death in undifferentiated cells. Acrylamide concentrations starting at 10fM attenuated the differentiation process in SH-SY5Y cells by sustaining cell proliferation and neurite outgrowth was reduced at concentrations from 10pM. Acrylamide significantly reduced the number of neurons starting at 1μM and altered the ratio between the different phenotypes in differentiating C17.2 cell cultures. Ten micromolar of acrylamide also reduced the expression of the neuronal and astrocyte biomarkers. Although the neurotoxic concentrations in the femtomolar range seem to be specific for the SH-SY5Y cell line, the fact that micromolar concentrations of acrylamide seem to attenuate the differentiation process in both cell lines raises the interest to further investigations on the possible developmental neurotoxicity of acrylamide.

  16. Cell Proliferation and Cytotoxicity Assays.

    PubMed

    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.

  17. Cell Proliferation, Cell Death, and Size Regulation

    DTIC Science & Technology

    1998-10-01

    Cell Death , and Size Regulation PRINCIPAL INVESTIGATOR: Nicholas E. Baker, Ph.D. CONTRACTING ORGANIZATION: Albert Einstein College of Medicine of Yeshiva...SUBTITLE 5. FUNDING NUMBERS Cell Proliferation, Cell Death , and Size Regulation DAMD17-97-1-7034 6. AUTHOR(S) Nicholas E. Baker, Ph.D. 7. PERFORMING...Contains unpublished data 5 CELL PROLIFERATION, CELL DEATH , AND SIZE REGULATION INTRODUCTION Cell proliferation and cell death come to attention through

  18. Preadipocyte proliferation is affected by norepinephrine

    SciTech Connect

    Jones, D.D.; Hausman, G.J.; Martin, R.J.

    1986-03-01

    Beta-adrenergic stimulators are known to alter body composition profiles in experimental animals. The most prominent in vivo adaptations to beta-agonists are a decreased adipose tissue and concurrent increased muscle mass. Our lab has previously reported that norepinephrine - a beta/sub 1/-agonist - compromised preadipocyte growth in a primary cell culture system. Accordingly, this study continued to examine the effect of norepinephrine (NE) on in vitro preadipocyte proliferation. Stromalvascular cells, obtained from the inguinal pad of 4-5 week old Sprague-Dawley rats, were grown in culture for two weeks. Cells were treated with NE (1 ..mu..M) during the proliferative growth phase and labelled with /sup 3/H-thymidine on day 2 of culture. Following exponential growth, all cells were placed on a differentiation promoting media. Adipocytes (including differentiated preadipocytes) and stromal cells were separated using a density gradient, and /sup 3/H-thymidine was determined for both cell types. NE exposure for 2 or 4 days significantly reduced preadipocyte /sup 3/H-thymidine uptake, indicating an inhibition of mitotic growth. Future experiments will examine possible mechanism(s) involved in the catecholamine induced suppression of preadipocyte proliferation.

  19. Importin β1 mediates nuclear factor-κB signal transduction into the nuclei of myeloma cells and affects their proliferation and apoptosis.

    PubMed

    Yan, Wenqing; Li, Rong; He, Jie; Du, Juan; Hou, Jian

    2015-04-01

    Multiple myeloma (MM) is a plasma cell neoplasm that is currently incurable. The activation of nuclear factor-κB (NF-κB) signalling plays a crucial role in the immortalisation of MM cells. As the most important transcription factor of the canonical NF-κB pathway, the p50/p65 heterodimer requires transportation into the nucleus for its successful signal transduction. Importin β1 is the key transport receptor that mediates p50/p65 nuclear import. Currently, it remains unclear whether the regulation of importin β1 function affects the biological behaviour of MM cells. In the present study, we investigated the changes in p65 translocation and the proliferation and apoptosis of MM cells after treatment with small interfering RNA (siRNA) or an importin β1 inhibitor. The underlying mechanisms were also investigated. We found importin β1 over-expression and the excessive nuclear transport of p65 in myeloma cells. Confocal laser scanning microscopy and Western blot analysis results indicated that p65 nuclear transport was blocked after inhibiting importin β1 expression with siRNA and the importin β1-specific inhibitor importazole (IPZ). Importantly, electronic mobility shift assay results also verified that p65 nuclear transport was dramatically reduced. Moreover, the expression of the NF-κB signalling target genes involved in MM cell apoptosis, such as BCL-2, c-IAP1 and XIAP, were markedly reduced, as demonstrated by the RT-PCR results. Furthermore, the proliferation of MM cells was inhibited, as demonstrated by MTT assay results, and the MM cell apoptosis rate was higher, as demonstrated by the annexin V/propidium iodide (PI) double-staining assay results. Additionally, the percentage of S phase cells in the myeloma cell lines treated with IPZ was dramatically reduced. In conclusion, our results clearly show that importin β1 mediates the translocation of NF-κB into the nuclei of myeloma cells, thereby regulating proliferation and blocking apoptosis, which

  20. Negative regulators of cell proliferation

    NASA Technical Reports Server (NTRS)

    Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Cell proliferation is governed by the influence of both mitogens and inhibitors. Although cell contact has long been thought to play a fundamental role in cell cycling regulation, and negative regulators have long been suspected to exist, their isolation and purification has been complicated by a variety of technical difficulties. Nevertheless, over recent years an ever-expanding list of putative negative regulators have emerged. In many cases, their biological inhibitory activities are consistent with density-dependent growth inhibition. Most likely their interactions with mitogenic agents, at an intracellular level, are responsible for either mitotic arrest or continued cell cycling. A review of naturally occurring cell growth inhibitors is presented with an emphasis on those factors shown to be residents of the cell surface membrane. Particular attention is focused on a cell surface sialoglycopeptide, isolated from intact bovine cerebral cortex cells, which has been shown to inhibit the proliferation of an unusually wide range of target cells. The glycopeptide arrest cells obtained from diverse species, both fibroblasts and epithelial cells, and a broad variety of transformed cells. Signal transduction events and a limited spectrum of cells that are refractory to the sialoglycopeptide have provided insight into the molecular events mediated by this cell surface inhibitor.

  1. Nuclear localization of CPI-17, a protein phosphatase-1 inhibitor protein, affects histone H3 phosphorylation and corresponds to proliferation of cancer and smooth muscle cells

    SciTech Connect

    Eto, Masumi; Kirkbride, Jason A.; Chugh, Rishika; Karikari, Nana Kofi; Kim, Jee In

    2013-04-26

    Highlights: •Non-canonical roles of the myosin phosphatase inhibitor (CPI-17) were studied. •CPI-17 is localized in the nucleus of hyperplastic cancer and smooth muscle cells. •CPI-17 Ser12 phosphorylation may regulate the nuclear import. •CPI-17 regulates histone H3 phosphorylation and cell proliferation. •The nuclear CPI-17-PP1 axis plays a proliferative role in cells. -- Abstract: CPI-17 (C-kinase-activated protein phosphatase-1 (PP1) inhibitor, 17 kDa) is a cytoplasmic protein predominantly expressed in mature smooth muscle (SM) that regulates the myosin-associated PP1 holoenzyme (MLCP). Here, we show CPI-17 expression in proliferating cells, such as pancreatic cancer and hyperplastic SM cells. Immunofluorescence showed that CPI-17 was concentrated in nuclei of human pancreatic cancer (Panc1) cells. Nuclear accumulation of CPI-17 was also detected in the proliferating vascular SM cell culture and cells at neointima of rat vascular injury model. The N-terminal 21-residue tail domain of CPI-17 was necessary for the nuclear localization. Phospho-mimetic Asp-substitution of CPI-17 at Ser12 attenuated the nuclear import. CPI-17 phosphorylated at Ser12 was not localized at nuclei, suggesting a suppressive role of Ser12 phosphorylation in the nuclear import. Activated CPI-17 bound to all three isoforms of PP1 catalytic subunit in Panc1 nuclear extracts. CPI-17 knockdown in Panc1 resulted in dephosphorylation of histone H3 at Thr3, Ser10 and Thr11, whereas it had no effects on the phosphorylation of myosin light chain and merlin, the known targets of MLCP. In parallel, CPI-17 knockdown suppressed Panc1 proliferation. We propose that CPI-17 accumulated in the nucleus through the N-terminal tail targets multiple PP1 signaling pathways regulating cell proliferation.

  2. Nuclear localization of CPI-17, a protein phosphatase-1 inhibitor protein, affects histone H3 phosphorylation and corresponds to proliferation of cancer and smooth muscle cells.

    PubMed

    Eto, Masumi; Kirkbride, Jason A; Chugh, Rishika; Karikari, Nana Kofi; Kim, Jee In

    2013-04-26

    CPI-17 (C-kinase-activated protein phosphatase-1 (PP1) inhibitor, 17kDa) is a cytoplasmic protein predominantly expressed in mature smooth muscle (SM) that regulates the myosin-associated PP1 holoenzyme (MLCP). Here, we show CPI-17 expression in proliferating cells, such as pancreatic cancer and hyperplastic SM cells. Immunofluorescence showed that CPI-17 was concentrated in nuclei of human pancreatic cancer (Panc1) cells. Nuclear accumulation of CPI-17 was also detected in the proliferating vascular SM cell culture and cells at neointima of rat vascular injury model. The N-terminal 21-residue tail domain of CPI-17 was necessary for the nuclear localization. Phospho-mimetic Asp-substitution of CPI-17 at Ser12 attenuated the nuclear import. CPI-17 phosphorylated at Ser12 was not localized at nuclei, suggesting a suppressive role of Ser12 phosphorylation in the nuclear import. Activated CPI-17 bound to all three isoforms of PP1 catalytic subunit in Panc1 nuclear extracts. CPI-17 knockdown in Panc1 resulted in dephosphorylation of histone H3 at Thr3, Ser10 and Thr11, whereas it had no effects on the phosphorylation of myosin light chain and merlin, the known targets of MLCP. In parallel, CPI-17 knockdown suppressed Panc1 proliferation. We propose that CPI-17 accumulated in the nucleus through the N-terminal tail targets multiple PP1 signaling pathways regulating cell proliferation.

  3. The expression of cell proliferation-related genes in early developing flowers is affected by a fruit load reduction in tomato plants.

    PubMed

    Baldet, Pierre; Hernould, Michel; Laporte, Frédéric; Mounet, Fabien; Just, Daniel; Mouras, Armand; Chevalier, Christian; Rothan, Christophe

    2006-01-01

    Changes in photoassimilate partitioning between source and sink organs significantly affect fruit development and size. In this study, a comparison was made of tomato plants (Solanum lycopersicum L.) grown under a low fruit load (one fruit per truss, L1 plants) and under a standard fruit load (five fruits per truss, L5 plants), at morphological, biochemical, and molecular levels. Fruit load reduction resulted in increased photoassimilate availability in the plant and in increased growth rates in all plant organs analysed (root, stem, leaf, flower, and fruit). Larger flower and fruit size in L1 plants were correlated with higher cell number in the pre-anthesis ovary. This was probably due to the acceleration of the flower growth rate since other flower developmental parameters (schedule and time-course) remained otherwise unaffected. Using RT-PCR, it was shown that the transcript levels of CYCB2;1 (cyclin) and CDKB2;1 (cyclin-dependent kinase), two mitosis-specific genes, strongly increased early in developing flower buds. Remarkably, the transcript abundance of CYCD3;1, a D-type cyclin potentially involved in cell cycle regulation in response to mitogenic signals, also increased by more than 5-fold at very early stages of L1 flower development. By contrast, transcripts from fw2.2, a putative negative regulator of cell division in tomato fruit, strongly decreased in developing flower bud, as confirmed by in situ hybridization studies. Taken together, these results suggest that changes in carbohydrate partitioning could control fruit size through the regulation of cell proliferation-related genes at very early stages of flower development.

  4. Platelets: cell proliferation and atherosclerosis.

    PubMed

    Ross, R

    1979-04-01

    Intimal smooth muscle proliferation is the hallmark of the lesions of atherosclerosis. Endothelial injury is postulated to precede this intimal smooth muscle proliferative response, which is mediated by a potent mitogenic factor derived from adherence, aggregation, and release by platelets at sites of endothelial injury. Smooth muscle proliferation is accompanied by varying amounts of connective tissue formation and intracellular and extracellular lipid deposition, dependent upon the risk factors encountered in each patient. The platelet-derived mitogen (PF) is a stable, cationic, relatively low molecular weight (10,000-30,000) protein that has been partially purified by ion exchange chromotography and gel filtration. Less than 100 ng of PF/ml culture medium can stimulate sparse 3T3 cells or smooth muscle cells, but not endothelial cells, to undergo multiple cell divisions in the presence of 5% cell-free, plasma-derived serum. The latter contains no mitogenic activity. The interaction of the platelet mitogen and plasma-derived components, including lipoproteins, plays a critical role in smooth muscle proliferation in vitro and in vivo in the induction of the lesions of atherosclerosis.

  5. Inhibitory activity of a heterochromatin-associated serpin (MENT) against papain-like cysteine proteinases affects chromatin structure and blocks cell proliferation.

    PubMed

    Irving, James A; Shushanov, Sain S; Pike, Robert N; Popova, Evgenya Y; Brömme, Dieter; Coetzer, Theresa H T; Bottomley, Stephen P; Boulynko, Iaroslava A; Grigoryev, Sergei A; Whisstock, James C

    2002-04-12

    MENT (Myeloid and Erythroid Nuclear Termination stage-specific protein) is a developmentally regulated chromosomal serpin that condenses chromatin in terminally differentiated avian blood cells. We show that MENT is an effective inhibitor of the papain-like cysteine proteinases cathepsins L and V. In addition, ectopic expression of MENT in mammalian cells is apparently sufficient to inhibit a nuclear papain-like cysteine proteinase and prevent degradation of the retinoblastoma protein, a major regulator of cell proliferation. MENT also accumulates in the nucleus, causes a strong block in proliferation, and promotes condensation of chromatin. Variants of MENT with mutations or deletions within the M-loop, which contains a nuclear localization signal and an AT-hook motif, reveal that this region mediates nuclear transport and morphological changes associated with chromatin condensation. Non-inhibitory mutants of MENT were constructed to determine whether its inhibitory activity has a role in blocking proliferation. These mutations changed the mode of association with chromatin and relieved the block in proliferation, without preventing transport to the nucleus. We conclude that the repressive effect of MENT on chromatin is mediated by its direct interaction with a nuclear protein that has a papain-like cysteine proteinase active site.

  6. Long noncoding RNA BLACAT1 indicates a poor prognosis of colorectal cancer and affects cell proliferation by epigenetically silencing of p15.

    PubMed

    Su, Jun; Zhang, Erbao; Han, Liang; Yin, Dandan; Liu, Zhili; He, Xuezhi; Zhang, Yuhong; Lin, Feng; Lin, Qingfeng; Mao, Peiyao; Mao, Weidong; Shen, Dong

    2017-03-09

    Recently, a novel class of transcripts, long noncoding RNAs (lncRNAs), is being identified at a rapid pace. These RNAs have critical roles in diverse biological processes, including tumorigenesis. One of them, BLACAT1, a cancer-associated long noncoding RNA, exerts regulatory functions in various biological processes in cancer cells, however, the role of BLACAT1 in colon cancer remains unclear. Our experiments showed that increased BLACAT1 was an independent unfavorable prognostic indicator for colorectal cancer, and revealed that BLACAT1 knockdown significantly repressed proliferation, both in vitro and in vivo. Mechanistic investigations demonstrated that BLACAT1 had a key role in G1/G0 arrest, and showed that BLACAT1 can repress p15 expression by binding to EZH2, thus contributing to the regulation of CRC cell cycle and proliferation. Our results suggest that BLACAT1, as a cell cycle regulator, may serve as a potential target for colon cancer prevention and treatment in human CRC.

  7. Eucommia ulmoides Oliv. (Du-Zhong) Lignans Inhibit Angiotensin II-Stimulated Proliferation by Affecting P21, P27, and Bax Expression in Rat Mesangial Cells

    PubMed Central

    Jing, Xian; Huang, Wei-Hua; Tang, Yong-Jun; Wang, Ya-Qin; Li, Hui; Tian, Ying-Ying; Chen, Yao; Zhou, Hong-Hao; Ouyang, Dong-Sheng

    2015-01-01

    Cortex Eucommiae (Du-zhong) is the dried bark of the Eucommia ulmoides Oliv. The natural products identified from Du-zhong include lignans, iridoids, flavonoids, polysaccharides, terpenes, and proteins, Liu et al. (2012). Lignans, the main bioactive components, were protective against hypertensive renal injury in spontaneous hypertensive rats in our previous study, Li et al. (2012). Moreover, Eucommia lignans also diminished aldose reductase (AR) overexpression in the kidney, Li et al. (2012). However, the pathological mechanism underlying the protective effects of Eucommia lignans remains unknown. Cellular proliferation was reported to contribute to important pathological changes in hypertensive renal injuries, and increased angiotensin II (Ang II) expression was reported to be essential for target-organ damage during hypertension. Ang II is the main effective peptide in the renin-angiotensin system and is considered to be a key mediator in the development of hypertensive nephropathy, Rüster and Wolf (2011). Our preliminary results showed that Eucommia lignans had inhibitory effects on Ang II-induced proliferation of rat mesangial cells. In the present study, we investigated the effects of Eucommia ulmoides on Ang II-induced proliferation and apoptosis of rat mesangial cells. Cell cycle-related genes P21 and P27, and cell apoptosis-related genes Bax and Bcl-2, were determined. PMID:26170892

  8. Sirtuin-2 inhibition affects hippocampal functions and sodium butyrate ameliorates the reduction in novel object memory, cell proliferation, and neuroblast differentiation

    PubMed Central

    Jung, Hyo Young; Yoo, Dae Young; Kim, Jong Whi; Kim, Dae Won; Choi, Jung Hoon; Chung, Jin Young; Won, Moo-Ho; Yoon, Yeo Sung

    2016-01-01

    We investigated the effects of the sirtuin-2 (SIRT2) inhibitor AK-7 on novel object memory, cell proliferation, and neuroblast differentiation in the dentate gyrus. In addition, we also observed the relationships with sodium butyrate, a histone deacetylase inhibitor, on the hippocampal functions. To investigate the effects of AK-7 on hippocampal functions, 10-week-old C57BL/6 mice were daily injected intraperitoneally with 20 mg/kg AK-7 alone or in combination with subcutaneous administration of 300 mg/kg sodium butyrate, a histone deacetylase inhibitor, for 21 days. A novel object recognition test was conducted on days 20 (training) and 21 (testing) of treatment. Thereafter, the animals were sacrificed for immunohistochemistry for Ki67 (cell proliferation) and doublecortin (DCX, neuroblast differentiation). AK-7 administration significantly reduced the time spent exploring new objects, while treatment in combination with sodium butyrate significantly alleviated this reduction. Additionally, AK-7 administration significantly reduced the number of Ki67-positive cells and DCX-immunoreactive neuroblasts in the dentate gyrus, while the treatment in combination with sodium butyrate ameliorated these changes. This result suggests that the reduction of SIRT2 may be closely related to age-related phenotypes including novel object memory, as well as cell proliferation and neuroblast differentiation in the dentate gyrus. In addition, sodium butyrate reverses SIRT2-related age phenotypes. PMID:28053616

  9. Cell proliferation in normal epidermis

    SciTech Connect

    Weinstein, G.D.; McCullough, J.L.; Ross, P.

    1984-06-01

    A detailed examination of cell proliferation kinetics in normal human epidermis is presented. Using tritiated thymidine with autoradiographic techniques, proliferative and differentiated cell kinetics are defined and interrelated. The proliferative compartment of normal epidermis has a cell cycle duration (Tc) of 311 h derived from 3 components: the germinative labeling index (LI), the duration of DNA synthesis (ts), and the growth fraction (GF). The germinative LI is 2.7% +/- 1.2 and ts is 14 h, the latter obtained from a composite fraction of labeled mitoses curve obtained from 11 normal subjects. The GF obtained from the literature and from human skin xenografts to nude mice is estimated to be 60%. Normal-appearing epidermis from patients with psoriasis appears to have a higher proliferation rate. The mean LI is 4.2% +/- 0.9, approximately 50% greater than in normal epidermis. Absolute cell kinetic values for this tissue, however, cannot yet be calculated for lack of other information on ts and GF. A kinetic model for epidermal cell renewal in normal epidermis is described that interrelates the rate of birth/entry, transit, and/or loss of keratinocytes in the 3 epidermal compartments: proliferative, viable differentiated (stratum malpighii), and stratum corneum. Expected kinetic homeostasis in the epidermis is confirmed by the very similar ''turnover'' rates in each of the compartments that are, respectively, 1246, 1417, and 1490 cells/day/mm2 surface area. The mean epidermal turnover time of the entire tissue is 39 days. The Tc of 311 h in normal cells in 8-fold longer than the psoriatic Tc of 36 h and is necessary for understanding the hyperproliferative pathophysiologic process in psoriasis.

  10. H3K27 acetylation activated-long non-coding RNA CCAT1 affects cell proliferation and migration by regulating SPRY4 and HOXB13 expression in esophageal squamous cell carcinoma.

    PubMed

    Zhang, Erbao; Han, Liang; Yin, Dandan; He, Xuezhi; Hong, Linzhi; Si, Xinxin; Qiu, Mantang; Xu, Tongpeng; De, Wei; Xu, Lin; Shu, Yongqian; Chen, Jinfei

    2016-12-11

    Recently, long non-coding RNAs (lncRNAs) have been shown to have important regulatory roles in human cancer biology. In our study, we found that lncRNA CCAT1, whose expression is significantly increased and is correlated with outcomes in Esophageal Squamous Cell Carcinoma (ESCC). Consecutive experiments confirmed that H3K27-acetylation could activate expression of colon cancer associated transcript-1 (CCAT1). Further experiments revealed that CCAT1 knockdown significantly repressed the proliferation and migration both in vitro and in vivo RNA-seq analysis revealed that CCAT1 knockdown preferentially affected genes that are linked to cell proliferation, cell migration and cell adhesion. Mechanistic investigations found that CCAT1 could serve as a scaffold for two distinct epigenetic modification complexes (5' domain of CCAT1 binding Polycomb Repressive Complex 2 (PRC2) while 3' domain of CCAT1 binding SUV39H1) and modulate the histone methylation of promoter of SPRY4 (sprouty RTK signaling antagonist 4) in nucleus. In cytoplasm, CCAT1 regulates HOXB13 as a molecular decoy for miR-7, a microRNA that targets both CCAT1 and HOXB13, thus facilitating cell growth and migration. Together, our data demonstrated the important roles of CCAT1 in ESCC oncogenesis and might serve as targets for ESCC diagnosis and therapy.

  11. Proliferation status defines functional properties of endothelial cells.

    PubMed

    Lipps, Christoph; Badar, Muhammad; Butueva, Milada; Dubich, Tatyana; Singh, Vivek Vikram; Rau, Sophie; Weber, Axel; Kracht, Michael; Köster, Mario; May, Tobias; Schulz, Thomas F; Hauser, Hansjörg; Wirth, Dagmar

    2017-04-01

    Homeostasis of solid tissue is characterized by a low proliferative activity of differentiated cells while special conditions like tissue damage induce regeneration and proliferation. For some cell types it has been shown that various tissue-specific functions are missing in the proliferating state, raising the possibility that their proliferation is not compatible with a fully differentiated state. While endothelial cells are important players in regenerating tissue as well as in the vascularization of tumors, the impact of proliferation on their features remains elusive. To examine cell features in dependence of proliferation, we established human endothelial cell lines in which proliferation is tightly controlled by a doxycycline-dependent, synthetic regulatory unit. We observed that uptake of macromolecules and establishment of cell-cell contacts was more pronounced in the growth-arrested state. Tube-like structures were formed in vitro in both proliferating and non-proliferating conditions. However, functional vessel formation upon transplantation into immune-compromised mice was restricted to the proliferative state. Kaposi's sarcoma-associated herpes virus (KSHV) infection resulted in reduced expression of endothelial markers. Upon transplantation of infected cells, drastic differences were observed: proliferation arrested cells acquired a high migratory activity while the proliferating counterparts established a tumor-like phenotype, similar to Kaposi Sarcoma lesions. The study gives evidence that proliferation governs endothelial functions. This suggests that several endothelial functions are differentially expressed during angiogenesis. Moreover, since proliferation defines the functional properties of cells upon infection with KSHV, this process crucially affects the fate of virus-infected cells.

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

    PubMed

    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.

  13. The poplar basic helix-loop-helix transcription factor BEE3 - Like gene affects biomass production by enhancing proliferation of xylem cells in poplar.

    PubMed

    Noh, Seol Ah; Choi, Young-Im; Cho, Jin-Seong; Lee, Hyoshin

    2015-06-19

    Brassinosteroids (BRs) play important roles in many aspects of plant growth and development, including regulation of vascular cambium activities and cell elongation. BR-induced BEE3 (brassinosteroid enhanced expression 3) is required for a proper BR response. Here, we identified a poplar (Populus alba × Populus glandulosa) BEE3-like gene, PagBEE3L, encoding a putative basic helix-loop-helix (bHLH)-type transcription factor. Expression of PagBEE3L was induced by brassinolide (BL). Transcripts of PagBEE3L were mainly detected in stems, with the internode having a low level of transcription and the node having a relatively higher level. The function of the PagBEE3L gene was investigated through phenotypic analyses with PagBEE3L-overexpressing (ox) transgenic lines. This work particularly focused on a potential role of PagBEE3L in stem growth and development of polar. The PagBEE3L-ox poplar showed thicker and longer stems than wild-type plants. The xylem cells from the stems of PagBEE3L-ox plants revealed remarkably enhanced proliferation, resulting in an earlier thickening growth than wild-type plants. Therefore, this work suggests that xylem development of poplar is accelerated in PagBEE3L-ox plants and PagBEE3L plays a role in stem growth by increasing the proliferation of xylem cells to promote the initial thickening growth of poplar stems.

  14. The poplar basic helix-loop-helix transcription factor BEE3 – Like gene affects biomass production by enhancing proliferation of xylem cells in poplar

    SciTech Connect

    Noh, Seol Ah Choi, Young-Im Cho, Jin-Seong Lee, Hyoshin

    2015-06-19

    Brassinosteroids (BRs) play important roles in many aspects of plant growth and development, including regulation of vascular cambium activities and cell elongation. BR-induced BEE3 (brassinosteroid enhanced expression 3) is required for a proper BR response. Here, we identified a poplar (Populus alba × Populus glandulosa) BEE3-like gene, PagBEE3L, encoding a putative basic helix-loop-helix (bHLH)-type transcription factor. Expression of PagBEE3L was induced by brassinolide (BL). Transcripts of PagBEE3L were mainly detected in stems, with the internode having a low level of transcription and the node having a relatively higher level. The function of the PagBEE3L gene was investigated through phenotypic analyses with PagBEE3L-overexpressing (ox) transgenic lines. This work particularly focused on a potential role of PagBEE3L in stem growth and development of polar. The PagBEE3L-ox poplar showed thicker and longer stems than wild-type plants. The xylem cells from the stems of PagBEE3L-ox plants revealed remarkably enhanced proliferation, resulting in an earlier thickening growth than wild-type plants. Therefore, this work suggests that xylem development of poplar is accelerated in PagBEE3L-ox plants and PagBEE3L plays a role in stem growth by increasing the proliferation of xylem cells to promote the initial thickening growth of poplar stems. - Highlights: • We identify the BEE3-like gene form hybrid poplar (Populus alba × Populus glandulosa). • We examine effects of overexpression of PagBEE3L on growth in poplar. • We found that 35S:BEE3L transgenic plants showed more rapid growth than wild-type plants. • BEE3L protein plays an important role in the development of plant stem.

  15. Power Frequency Magnetic Fields Affect the p38 MAPK-Mediated Regulation of NB69 Cell Proliferation Implication of Free Radicals

    PubMed Central

    Martínez, María Antonia; Úbeda, Alejandro; Moreno, Jorge; Trillo, María Ángeles

    2016-01-01

    The proliferative response of the neuroblastoma line NB69 to a 100 µT, 50 Hz magnetic field (MF) has been shown mediated by activation of the MAPK-ERK1/2 pathway. This work investigates the MF effect on the cell cycle of NB69, the participation of p38 and c-Jun N-terminal (JNK) kinases in the field-induced proliferative response and the potential involvement of reactive oxygen species (ROS) in the activation of the MAPK-ERK1/2 and -p38 signaling pathways. NB69 cultures were exposed to the 100 µT MF, either intermittently for 24, 42 or 63 h, or continuously for periods of 15 to 120 min, in the presence or absence of p38 or JNK inhibitors: SB203580 and SP600125, respectively. Antioxidant N-acetylcysteine (NAC) was used as ROS scavenger. Field exposure induced transient activation of p38, JNK and ERK1/2. The MF proliferative effect, which was mediated by changes in the cell cycle, was blocked by the p38 inhibitor, but not by the JNK inhibitor. NAC blocked the field effects on cell proliferation and p38 activation, but not those on ERK1/2 activation. The MF-induced proliferative effects are exerted through sequential upregulation of MAPK-p38 and -ERK1/2 activation, and they are likely mediated by a ROS-dependent activation of p38. PMID:27058530

  16. Power Frequency Magnetic Fields Affect the p38 MAPK-Mediated Regulation of NB69 Cell Proliferation Implication of Free Radicals.

    PubMed

    Martínez, María Antonia; Úbeda, Alejandro; Moreno, Jorge; Trillo, María Ángeles

    2016-04-06

    The proliferative response of the neuroblastoma line NB69 to a 100 µT, 50 Hz magnetic field (MF) has been shown mediated by activation of the MAPK-ERK1/2 pathway. This work investigates the MF effect on the cell cycle of NB69, the participation of p38 and c-Jun N-terminal (JNK) kinases in the field-induced proliferative response and the potential involvement of reactive oxygen species (ROS) in the activation of the MAPK-ERK1/2 and -p38 signaling pathways. NB69 cultures were exposed to the 100 µT MF, either intermittently for 24, 42 or 63 h, or continuously for periods of 15 to 120 min, in the presence or absence of p38 or JNK inhibitors: SB203580 and SP600125, respectively. Antioxidant N-acetylcysteine (NAC) was used as ROS scavenger. Field exposure induced transient activation of p38, JNK and ERK1/2. The MF proliferative effect, which was mediated by changes in the cell cycle, was blocked by the p38 inhibitor, but not by the JNK inhibitor. NAC blocked the field effects on cell proliferation and p38 activation, but not those on ERK1/2 activation. The MF-induced proliferative effects are exerted through sequential upregulation of MAPK-p38 and -ERK1/2 activation, and they are likely mediated by a ROS-dependent activation of p38.

  17. Cell proliferation in human coronary arteries.

    PubMed Central

    Gordon, D; Reidy, M A; Benditt, E P; Schwartz, S M

    1990-01-01

    Despite the lack of direct evidence for cell multiplication, proliferation of smooth muscle cells in human atherosclerotic lesions has been assumed to play a central role in ontogeny of the plaque. We used antibodies to cell cycle-related proteins on tissue sections of human arteries and coronary atherosclerotic plaques. Specific cell types were identified by immunochemical reagents for smooth muscle, monocyte-macrophages, and other blood cells. Low rates of smooth muscle cell proliferation were observed. Macrophages were also observed with rates of proliferation comparable to that of the smooth muscle. Additional replicating cells could not be defined as belonging to specific cell types with the reagents used in this study. These findings imply that smooth muscle replication in advanced plaques is indolent and raise the possibility of a role for proliferating leukocytes. Images PMID:1972277

  18. Cycling hypoxia affects cell invasion and proliferation through direct regulation of claudin1 / claudin7 expression, and indirect regulation of P18 through claudin7.

    PubMed

    Liu, Hong; Jiang, Feifei; Jia, Xinshan; Lan, Jing; Guo, Hao; Li, Erran; Yan, Aihui; Wang, Yan

    2017-02-07

    Claudins (CLDNs), the major integral membrane proteins at tight junction, play critical roles in apical cell-to-cell adhesion, maintenance of epithelial polarity, and formation of impermeable barriers between epithelial cells.We investigated in this study the expression of CLDNs- Claudin1 (CLDN1) and Claudin7 (CLDN7), and their relation to tumor progression in nasopharyngeal cancer (NPC). CLDN7, rather than CLDN1, showed higher expression in both undifferentiated tumor tissue and the poorly differentiated CNE2 cells, compared with differentiated tissue and the highly differentiated CNE1 cells. Furthermore, knockdown of CLDN7 dramatically inhibited the metastasis and invasion of CNE2 cells suggesting that CLDN7 could act as a biomarker for NPC metastasis.Cycling hypoxia could induce significant changes in CLDN1 and CLDN7 expression in NPC cells. Genetics analysis demonstrated that CLDN1/CLDN7 were not only regulated directly by HIF1a but also affected each other through a feedback mechanism. CLDN7 acted as a bridge to promote HIF1a-induced P18 expression and cell differentiation. Taken together, our results provide evidence that adjusting the oxygenation time and cycles in NPC might be an effective method to prevent / delay the metastasis of poorly differentiated NPC cells.

  19. Human Articular Chondrocytes Regulate Immune Response by Affecting Directly T Cell Proliferation and Indirectly Inhibiting Monocyte Differentiation to Professional Antigen-Presenting Cells

    PubMed Central

    Pereira, Rui C.; Martinelli, Daniela; Cancedda, Ranieri; Gentili, Chiara; Poggi, Alessandro

    2016-01-01

    Autologous chondrocyte implantation is the current gold standard cell therapy for cartilage lesions. However, in some instances, the heavily compromised health of the patient can either impair or limit the recovery of the autologous chondrocytes and a satisfactory outcome of the implant. Allogeneic human articular chondrocytes (hAC) could be a good alternative, but the possible immunological incompatibility between recipient and hAC donor should be considered. Herein, we report that allogeneic hAC inhibited T lymphocyte response to antigen-dependent and -independent proliferative stimuli. This effect was maximal when T cells and hAC were in contact and it was not relieved by the addition of exogenous lymphocyte growth factor interleukin (IL)-2. More important, hAC impaired the differentiation of peripheral blood monocytes induced with granulocyte monocyte colony-stimulating factor and IL-4 (Mo) to professional antigen-presenting cells, such as dendritic cells (DC). Indeed, a marked inhibition of the onset of the CD1a expression and an ineffective downregulation of CD14 antigens was observed in Mo–hAC co-cultures. Furthermore, compared to immature or mature DC, Mo from Mo–hAC co-cultures did not trigger an efficacious allo-response. The prostaglandin (PG) E2 present in the Mo–hAC co-culture conditioned media is a putative candidate of the hAC-mediated inhibition of Mo maturation. Altogether, these findings indicate that allogeneic hAC inhibit, rather than trigger, immune response and strongly suggest that an efficient chondrocyte implantation could be possible also in an allogeneic setting. PMID:27822208

  20. Cell proliferation within small intestinal crypts is the principal driving force for cell migration on villi.

    PubMed

    Parker, Aimee; Maclaren, Oliver J; Fletcher, Alexander G; Muraro, Daniele; Kreuzaler, Peter A; Byrne, Helen M; Maini, Philip K; Watson, Alastair J M; Pin, Carmen

    2017-02-01

    The functional integrity of the intestinal epithelial barrier relies on tight coordination of cell proliferation and migration, with failure to regulate these processes resulting in disease. It is not known whether cell proliferation is sufficient to drive epithelial cell migration during homoeostatic turnover of the epithelium. Nor is it known precisely how villus cell migration is affected when proliferation is perturbed. Some reports suggest that proliferation and migration may not be related while other studies support a direct relationship. We used established cell-tracking methods based on thymine analog cell labeling and developed tailored mathematical models to quantify cell proliferation and migration under normal conditions and when proliferation is reduced and when it is temporarily halted. We found that epithelial cell migration velocities along the villi are coupled to cell proliferation rates within the crypts in all conditions. Furthermore, halting and resuming proliferation results in the synchronized response of cell migration on the villi. We conclude that cell proliferation within the crypt is the primary force that drives cell migration along the villus. This methodology can be applied to interrogate intestinal epithelial dynamics and characterize situations in which processes involved in cell turnover become uncoupled, including pharmacological treatments and disease models.-Parker, A., Maclaren, O. J., Fletcher, A. G., Muraro, D., Kreuzaler, P. A., Byrne, H. M., Maini, P. K., Watson, A. J. M., Pin, C. Cell proliferation within small intestinal crypts is the principal driving force for cell migration on villi.

  1. Cell proliferation within small intestinal crypts is the principal driving force for cell migration on villi

    PubMed Central

    Parker, Aimee; Maclaren, Oliver J.; Fletcher, Alexander G.; Muraro, Daniele; Kreuzaler, Peter A.; Byrne, Helen M.; Maini, Philip K.; Watson, Alastair J. M.; Pin, Carmen

    2017-01-01

    The functional integrity of the intestinal epithelial barrier relies on tight coordination of cell proliferation and migration, with failure to regulate these processes resulting in disease. It is not known whether cell proliferation is sufficient to drive epithelial cell migration during homoeostatic turnover of the epithelium. Nor is it known precisely how villus cell migration is affected when proliferation is perturbed. Some reports suggest that proliferation and migration may not be related while other studies support a direct relationship. We used established cell-tracking methods based on thymine analog cell labeling and developed tailored mathematical models to quantify cell proliferation and migration under normal conditions and when proliferation is reduced and when it is temporarily halted. We found that epithelial cell migration velocities along the villi are coupled to cell proliferation rates within the crypts in all conditions. Furthermore, halting and resuming proliferation results in the synchronized response of cell migration on the villi. We conclude that cell proliferation within the crypt is the primary force that drives cell migration along the villus. This methodology can be applied to interrogate intestinal epithelial dynamics and characterize situations in which processes involved in cell turnover become uncoupled, including pharmacological treatments and disease models.—Parker, A., Maclaren, O. J., Fletcher, A. G., Muraro, D., Kreuzaler, P. A., Byrne, H. M., Maini, P. K., Watson, A. J. M., Pin, C. Cell proliferation within small intestinal crypts is the principal driving force for cell migration on villi. PMID:27811059

  2. Inhibition of brain tumor cell proliferation by alternating electric fields

    SciTech Connect

    Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi E-mail: radioyoon@korea.ac.kr; Sung, Jiwon; Jeong, Seonghoon; Yoon, Myonggeun E-mail: radioyoon@korea.ac.kr; Koh, Eui Kwan

    2014-11-17

    This study was designed to investigate the mechanism by which electric fields affect cell function, and to determine the optimal conditions for electric field inhibition of cancer cell proliferation. Low-intensity (<2 V/cm) and intermediate-frequency (100–300 kHz) alternating electric fields were applied to glioblastoma cell lines. These electric fields inhibited cell proliferation by inducing cell cycle arrest and abnormal mitosis due to the malformation of microtubules. These effects were significantly dependent on the intensity and frequency of applied electric fields.

  3. Long noncoding RNA MEG3 is downregulated in cervical cancer and affects cell proliferation and apoptosis by regulating miR-21.

    PubMed

    Zhang, Jun; Yao, Tingting; Wang, Yaxian; Yu, Jin; Liu, Yunyun; Lin, Zhongqiu

    2016-01-01

    Recent research has found that long noncoding RNAs (lncRNAs) were involved in various human cancers. However, the role of these lncRNAs in cervical cancer remains unexplored. Therefore, we aimed to investigate the biological function of maternally expressed gene 3 (MEG3), a cancer-related lncRNA, and its underlying mechanism in cervical cancer. In this study, MEG3 expression of 108 patients' cervical cancer tissues and adjacent normal tissues was detected by quantitative real-time PCR analysis (qRT-PCR), and the functional effect of MEG3 was determined in vitro assays. We observed that MEG3 was downregulated in cervical cancer tissues, compared to the adjacent normal tissues, and was negatively related with FIGO stages, tumor size, lymphatic metastasis, HR-HPV infection and the expression of homo sapiens microRNA-21 (miR-21). Furthermore, we focused on the function and molecular mechanism of MEG3, finding that overexpression of MEG3 reduced the level of miR-21-5p expression, causing inhibition of proliferation and increased apoptosis in cervical cancer cells. In summary, our findings indicate that MEG3 function as a tumor suppressor by regulating miR-21-5p, resulting in the inhibition of tumor growth in cervical cancer. As a result, this study improves our understanding of the function of MEG3 in cervical cancer and will help to provide new potential target sites for cervical cancer treatment.

  4. Metformin inhibits the proliferation of benign prostatic epithelial cells

    PubMed Central

    Ge, Rongbin; Li, Jijun; Johnson, Cameron W.; Rassoulian, Cyrus; Olumi, Aria F.

    2017-01-01

    Objective Benign prostatic hyperplasia (BPH) is the most common proliferative abnormality of the prostate affecting elderly men throughout the world. Epidemiologic studies have shown that diabetes significantly increases the risk of developing BPH, although whether anti-diabetic medications preventing the development of BPH remains to be defined. We have previously found that stromally expressed insulin-like growth factor 1 (IGF-1) promotes benign prostatic epithelial cell proliferation through paracrine mechanisms. Here, we seek to understand if metformin, a first line medication for the treatment of type 2 diabetes, inhibits the proliferation of benign prostatic epithelial cells through reducing the expression of IGF-1 receptor (IGF-1R) and regulating cell cycle. Methods BPE cell lines BPH-1 and P69, murine fibroblasts3T3 and primary human prostatic fibroblasts were cultured and tested in this study. Cell proliferation and the cell cycle were analyzed by MTS assay and flow cytometry, respectively. The expression of IGF-1R was determined by western-blot and immunocytochemistry. The level of IGF-1 secretion in culture medium was measured by ELISA. Results Metformin (0.5-10mM, 6-48h) significantly inhibited the proliferation of BPH-1 and P69 cells in a dose-dependent and time-dependent manner. Treatment with metformin for 24 hours lowered the G2/M cell population by 43.24% in P69 cells and 24.22% in BPH-1 cells. On the other hand, IGF-1 (100ng/mL, 24h) stimulated the cell proliferation (increased by 28.81% in P69 cells and 20.95% in BPH-1 cells) and significantly enhanced the expression of IGF-1R in benign prostatic epithelial cells. Metformin (5mM) abrogated the proliferation of benign prostatic epithelial cells induced by IGF-1. In 3T3 cells, the secretion of IGF-1 was significantly inhibited by metformin from 574.31pg/ml to 197.61pg/ml. The conditioned media of 3T3 cells and human prostatic fibroblasts promoted the proliferation of epithelial cells and the

  5. The endogenous cannabinoid anandamide inhibits human breast cancer cell proliferation

    PubMed Central

    De Petrocellis, Luciano; Melck, Dominique; Palmisano, Antonella; Bisogno, Tiziana; Laezza, Chiara; Bifulco, Maurizio; Di Marzo, Vincenzo

    1998-01-01

    Anandamide was the first brain metabolite shown to act as a ligand of “central” CB1 cannabinoid receptors. Here we report that the endogenous cannabinoid potently and selectively inhibits the proliferation of human breast cancer cells in vitro. Anandamide dose-dependently inhibited the proliferation of MCF-7 and EFM-19 cells with IC50 values between 0.5 and 1.5 μM and 83–92% maximal inhibition at 5–10 μM. The proliferation of several other nonmammary tumoral cell lines was not affected by 10 μM anandamide. The anti-proliferative effect of anandamide was not due to toxicity or to apoptosis of cells but was accompanied by a reduction of cells in the S phase of the cell cycle. A stable analogue of anandamide (R)-methanandamide, another endogenous cannabinoid, 2-arachidonoylglycerol, and the synthetic cannabinoid HU-210 also inhibited EFM-19 cell proliferation, whereas arachidonic acid was much less effective. These cannabimimetic substances displaced the binding of the selective cannabinoid agonist [3H]CP 55,940 to EFM-19 membranes with an order of potency identical to that observed for the inhibition of EFM-19 cell proliferation. Moreover, anandamide cytostatic effect was inhibited by the selective CB1 receptor antagonist SR 141716A. Cell proliferation was arrested by a prolactin mAb and enhanced by exogenous human prolactin, whose mitogenic action was reverted by very low (0.1–0.5 μM) doses of anandamide. Anandamide suppressed the levels of the long form of the prolactin receptor in both EFM-19 and MCF-7 cells, as well as a typical prolactin-induced response, i.e., the expression of the breast cancer cell susceptibility gene brca1. These data suggest that anandamide blocks human breast cancer cell proliferation through CB1-like receptor-mediated inhibition of endogenous prolactin action at the level of prolactin receptor. PMID:9653194

  6. Cell proliferation and differentiation in chemical leukemogenesis

    NASA Technical Reports Server (NTRS)

    Irons, R. D.; Stillman, W. S.; Clarkson, T. W. (Principal Investigator)

    1993-01-01

    In tissues such as bone marrow with normally high rates of cell division, proliferation is tightly coordinated with cell differentiation. Survival, proliferation and differentiation of early hematopoietic progenitor cells depend on the growth factors, interleukin 3 (IL-3) and/or granulocyte-macrophage colony stimulating factor (GM-CSF) and their synergism with other cytokines. We provide evidence that a characteristic shared by a diverse group of compounds with demonstrated leukemogenic potential is the ability to act synergistically with GM-CSF. This results in an increase in recruitment of a resting population of hematopoietic progenitor cells normally unresponsive to the cytokine and a twofold increase in the size of the proliferating cell population normally regarded to be at risk of transformation in leukemogenesis. These findings support the possibility that transient alterations in hematopoietic progenitor cell differentiation may be an important factor in the early stages of development of leukemia secondary to chemical or drug exposure.

  7. Blue light inhibits proliferation of melanoma cells

    NASA Astrophysics Data System (ADS)

    Becker, Anja; Distler, Elisabeth; Klapczynski, Anna; Arpino, Fabiola; Kuch, Natalia; Simon-Keller, Katja; Sticht, Carsten; van Abeelen, Frank A.; Gretz, Norbert; Oversluizen, Gerrit

    2016-03-01

    Photobiomodulation with blue light is used for several treatment paradigms such as neonatal jaundice, psoriasis and back pain. However, little is known about possible side effects concerning melanoma cells in the skin. The aim of this study was to assess the safety of blue LED irradiation with respect to proliferation of melanoma cells. For that purpose we used the human malignant melanoma cell line SK-MEL28. Cell proliferation was decreased in blue light irradiated cells where the effect size depended on light irradiation dosage. Furthermore, with a repeated irradiation of the melanoma cells on two consecutive days the effect could be intensified. Fluorescence-activated cell sorting with Annexin V and Propidium iodide labeling did not show a higher number of dead cells after blue light irradiation compared to non-irradiated cells. Gene expression analysis revealed down-regulated genes in pathways connected to anti-inflammatory response, like B cell signaling and phagosome. Most prominent pathways with up-regulation of genes were cytochrome P450, steroid hormone biosynthesis. Furthermore, even though cells showed a decrease in proliferation, genes connected to the cell cycle were up-regulated after 24h. This result is concordant with XTT test 48h after irradiation, where irradiated cells showed the same proliferation as the no light negative control. In summary, proliferation of melanoma cells can be decreased using blue light irradiation. Nevertheless, the gene expression analysis has to be further evaluated and more studies, such as in-vivo experiments, are warranted to further assess the safety of blue light treatment.

  8. Simvastatin suppresses breast cancer cell proliferation induced by senescent cells

    PubMed Central

    Liu, Su; Uppal, Harpreet; Demaria, Marco; Desprez, Pierre-Yves; Campisi, Judith; Kapahi, Pankaj

    2015-01-01

    Cellular senescence suppresses cancer by preventing the proliferation of damaged cells, but senescent cells can also promote cancer though the pro-inflammatory senescence-associated secretory phenotype (SASP). Simvastatin, an HMG-coA reductase inhibitor, is known to attenuate inflammation and prevent certain cancers. Here, we show that simvastatin decreases the SASP of senescent human fibroblasts by inhibiting protein prenylation, without affecting the senescent growth arrest. The Rho family GTPases Rac1 and Cdc42 were activated in senescent cells, and simvastatin reduced both activities. Further, geranylgeranyl transferase, Rac1 or Cdc42 depletion reduced IL-6 secretion by senescent cells. We also show that simvastatin mitigates the effects of senescent conditioned media on breast cancer cell proliferation and endocrine resistance. Our findings identify a novel activity of simvastatin and mechanism of SASP regulation. They also suggest that senescent cells, which accumulate after radio/chemo therapy, promote endocrine resistance in breast cancer and that simvastatin might suppress this resistance. PMID:26658759

  9. Lensless imaging system to quantify cell proliferation

    NASA Astrophysics Data System (ADS)

    Vinjimore Kesavan, S.; Allier, C. P.; Navarro, F.; Mittler, F.; Chalmond, B.; Dinten, J.-M.

    2013-02-01

    Owing to its simplicity, lensless imaging system is adept at continuous monitoring of adherent cells inside the incubator. The setup consists of a CMOS sensor with pixel pitch of 2.2 μm and field of view of 24 mm2, LED with a dominating wavelength of 525 nm, along with a pinhole of 150 μm as the source of illumination. The in-line hologram obtained from cells depends on the degree of cell-substrate adhesion. Drastic difference is observed between the holographic patterns of floating and adherent cells. In addition, the well-established fact of reduction of cell-substrate contact during cell division is observed with our system based on corresponding spontaneous transition in the holographic pattern. Here, we demonstrate that by recognizing this specific holographic pattern, number of cells undergoing mitosis in a cell culture with a population of approximately 5000 cells, can be estimated in real-time. The method is assessed on comparison with Edu-based proliferation assay. The approach is straightforward and it eliminates the use of markers to estimate the proliferation rate of a given cell culture. Unlike most proliferation assays, the cells are not harvested enabling continuous monitoring of cell culture.

  10. Stereotyped distribution of proliferating keratinocytes in disorders affecting the epidermis

    SciTech Connect

    Pierard-Franchimont, C.; Pierard, G.E.

    1989-06-01

    We used the technique of autoradiography after incorporation of tritiated thymidine (/sup 3/H-TdR) to evaluate keratinocyte proliferation in basal, epibasal, and other epidermal layers in 30 diseases affecting the epidermis. The number and proportion of /sup 3/H-TdR-labeled keratinocytes were counted in the different layers of the epidermis. Significant correlations were found between the proliferative indices of the different epidermal layers. Such links indicate that the epidermis responds in a rather stereotyped way to various pathological conditions. There exists some regulation in the distribution, number, and proportion of /sup 3/H-TdR-labeled keratinocytes in the various layers of the epidermis.

  11. Carnosine inhibits KRAS-mediated HCT116 proliferation by affecting ATP and ROS production.

    PubMed

    Iovine, Barbara; Iannella, Maria Luigia; Nocella, Francesca; Pricolo, Maria Rosaria; Bevilacqua, Maria Assunta

    2012-02-28

    Carnosine is a natural dipeptide that has generated particular interest for its antioxidant, anti-aging and especially for its antiproliferative properties. In this study, we demonstrate that carnosine inhibits the proliferation of human HCT116 colon cancer cells. In this cell line, the activating KRAS mutation induces mitochondrial ROS, the signaling molecules for cell proliferation. We observed that 50-100 mM carnosine decreases ATP and ROS concentration and induces cell cycle arrest in G1 phase. In HCT116 cells these effects are related to decreased ERK1/2 phosphorylation and increased p21waf1 protein. Our findings support the concept that carnosine could inhibit HCT116 cell growth via its antioxidant activity and its ability to affect glycolysis.

  12. Lysophosphatidic acid possesses dual action in cell proliferation.

    PubMed Central

    Tigyi, G; Dyer, D L; Miledi, R

    1994-01-01

    Lysophosphatidic acid (LPA) induces mitogenic responses in cultured fibroblasts through a pertussis toxin-sensitive signaling pathway. In contrast, we have shown that LPA inhibits the proliferation of Sp2/0-Ag14 myeloma cells. To resolve this apparent controversy, LPA-elicited responses in cell proliferation and the underlying second messenger mechanisms were compared in Sp2/0-Ag14 myeloma and NIH 3T3 fibroblast cells. The antimitogenic response was not elicited by micromolar concentrations of phosphatidic acid, phosphatidylglycerol, or diacylglycerol. In NIH 3T3 and Sp2 cells, LPA elicited an increase in inositol trisphosphate and a subsequent transient increase in free cytoplasmic Ca2+. Unlike the mitogenic response in NIH 3T3 cells, the antimitogenic effect was not affected by pertussis toxin; on the contrary, it was accompanied by an increase in cAMP. In Sp2 cells, cAMP analogs, forskolin, and isobutylmethylxanthine inhibited cell proliferation and enhanced LPA action in an additive manner, suggesting that an LPA-elicited increase in cAMP-mediated signaling was responsible for the antimitogenic response. In addition to the mitogenic response in fibroblasts and the antimitogenic response in tumor cell lines, there are some cell types (Jurkat T-cell lymphoma and primary astrocytes) in which LPA is ineffective in altering cell proliferation. The cell-type-specific dual action of LPA suggests that this endogenous lipid mediator when released from activated cells might play an important role as a regulator, rather than a ubiquitous inducer, of cell proliferation. Images PMID:8127904

  13. Microfluidic devices for cell cultivation and proliferation

    PubMed Central

    Tehranirokh, Masoomeh; Kouzani, Abbas Z.; Francis, Paul S.; Kanwar, Jagat R.

    2013-01-01

    Microfluidic technology provides precise, controlled-environment, cost-effective, compact, integrated, and high-throughput microsystems that are promising substitutes for conventional biological laboratory methods. In recent years, microfluidic cell culture devices have been used for applications such as tissue engineering, diagnostics, drug screening, immunology, cancer studies, stem cell proliferation and differentiation, and neurite guidance. Microfluidic technology allows dynamic cell culture in microperfusion systems to deliver continuous nutrient supplies for long term cell culture. It offers many opportunities to mimic the cell-cell and cell-extracellular matrix interactions of tissues by creating gradient concentrations of biochemical signals such as growth factors, chemokines, and hormones. Other applications of cell cultivation in microfluidic systems include high resolution cell patterning on a modified substrate with adhesive patterns and the reconstruction of complicated tissue architectures. In this review, recent advances in microfluidic platforms for cell culturing and proliferation, for both simple monolayer (2D) cell seeding processes and 3D configurations as accurate models of in vivo conditions, are examined. PMID:24273628

  14. Distinct T helper cell dependence of memory B-cell proliferation versus plasma cell differentiation.

    PubMed

    Zabel, Franziska; Fettelschoss, Antonia; Vogel, Monique; Johansen, Pål; Kündig, Thomas M; Bachmann, Martin F

    2017-03-01

    Several memory B-cell subclasses with distinct functions have been described, of which the most effective is the class-switched (CS) memory B-cell population. We have previously shown, using virus-like particles (VLPs), that the proliferative potential of these CS memory B cells is limited and they fail to re-enter germinal centres (GCs). However, VLP-specific memory B cells quickly differentiated into secondary plasma cells (PCs) with the virtue of elevated antibody production compared with primary PCs. Whereas the induction of VLP(+) memory B cells was strongly dependent on T helper cells, we were wondering whether re-stimulation of VLP(+) memory B cells and their differentiation into secondary PCs would also require T helper cells. Global absence of T helper cells led to strongly impaired memory B cell proliferation and PC differentiation. In contrast, lack of interleukin-21 receptor-dependent follicular T helper cells or CD40 ligand signalling strongly affected proliferation of memory B cells, but differentiation into mature secondary PCs exhibiting increased antibody production was essentially normal. This contrasts with primary B-cell responses, where a strong dependence on CD40 ligand but limited importance of interleukin-21 receptor was seen. Hence, T helper cell dependence differs between primary and secondary B-cell responses as well as between memory B-cell proliferation and PC differentiation.

  15. Development of bioengineering system for stem cell proliferation

    NASA Astrophysics Data System (ADS)

    Park, H. S.; Shah, R.; Shah, C.

    2016-08-01

    From last decades, intensive research in the field of stem cells proliferation had been promoted due to the unique property of stem cells to self-renew themselves into multiples and has potential to replicate into an organ or tissues and so it's highly demanding though challenging. Bioreactor, a mechanical device, works as a womb for stem cell proliferation by providing nutritious environment for the proper growth of stem cells. Various factors affecting stem cells growth are the bioreactor mechanism, feeding of continuous nutrients, healthy environment, etc., but it always remains a challenge for controlling biological parameters. The present paper unveils the design of mechanical device commonly known as bioreactor in tissues engineering and biotech field, use for proliferation of stem cells and imparts the proper growing condition for stem cells. This high functional bioreactor provides automation mixing of cell culture and stem cells. This design operates in conjunction with mechanism of reciprocating motion. Compare to commercial bioreactors, this proposed design is more convenient, easy to operate and less maintenance is required as bioreactor culture bag is made of polyethylene which is single use purpose. Development of this bioengineering system will be beneficial for better growth and expansion of stem cell

  16. Proliferation control in neural stem and progenitor cells

    PubMed Central

    Homem, Catarina CF; Repic, Marko; Knoblich, Juergen A

    2015-01-01

    Neural circuit function can be drastically affected by variations in the number of cells that are produced during development or by a reduction in adult cell number due to disease. Unlike many other organs, the brain is unable to compensate for such changes by increasing cell numbers or altering the size of the cells. For this reason, unique cell cycle and cell growth control mechanisms operate in the developing and adult brain. In Drosophila melanogaster and mammalian neural stem and progenitor cells these mechanisms are intricately coordinated with the developmental age and the nutritional, metabolic and hormonal state of the animal. Defects in neural stem cell proliferation that result in the generation of incorrect cell numbers or defects in neural stem cell differentiation can cause microcephaly or megalencephaly. PMID:26420377

  17. The cell proliferation antigen Ki-67 organises heterochromatin

    PubMed Central

    Sobecki, Michal; Mrouj, Karim; Camasses, Alain; Parisis, Nikolaos; Nicolas, Emilien; Llères, David; Gerbe, François; Prieto, Susana; Krasinska, Liliana; David, Alexandre; Eguren, Manuel; Birling, Marie-Christine; Urbach, Serge; Hem, Sonia; Déjardin, Jérôme; Malumbres, Marcos; Jay, Philippe; Dulic, Vjekoslav; Lafontaine, Denis LJ; Feil, Robert; Fisher, Daniel

    2016-01-01

    Antigen Ki-67 is a nuclear protein expressed in proliferating mammalian cells. It is widely used in cancer histopathology but its functions remain unclear. Here, we show that Ki-67 controls heterochromatin organisation. Altering Ki-67 expression levels did not significantly affect cell proliferation in vivo. Ki-67 mutant mice developed normally and cells lacking Ki-67 proliferated efficiently. Conversely, upregulation of Ki-67 expression in differentiated tissues did not prevent cell cycle arrest. Ki-67 interactors included proteins involved in nucleolar processes and chromatin regulators. Ki-67 depletion disrupted nucleologenesis but did not inhibit pre-rRNA processing. In contrast, it altered gene expression. Ki-67 silencing also had wide-ranging effects on chromatin organisation, disrupting heterochromatin compaction and long-range genomic interactions. Trimethylation of histone H3K9 and H4K20 was relocalised within the nucleus. Finally, overexpression of human or Xenopus Ki-67 induced ectopic heterochromatin formation. Altogether, our results suggest that Ki-67 expression in proliferating cells spatially organises heterochromatin, thereby controlling gene expression. DOI: http://dx.doi.org/10.7554/eLife.13722.001 PMID:26949251

  18. The Stochastic Theory of Cell Proliferation

    PubMed Central

    Bronk, Burt V.; Dienes, G. J.; Paskin, Arthur

    1968-01-01

    A stochastic theory of cell kinetics has been developed based on a realistic model of cell proliferation. A characteristic transit time, t̄i, has been assigned to each of the four states (G1, S, G2, M) of the cell cycle. The actual transit time, ti, for any cell is represented by a distribution around t̄i with a variance σi2. Analytic and computer formulations have been used to describe the time development of such characteristics as age distribution, labeling experiments, and response to perturbations of the system by, for example, irradiation and temperature. The decay of synchrony is analyzed in detail and is shown to proceed as a damped wave. From the first few peaks of the synchrony decay one can obtain the distribution function for the cell cycle time. The later peaks decay exponentially with a characteristic decay constant, λ, which depends only on the average cell-cycle time, T̄, and the associated variance. It is shown that the system, upon any sudden disturbance, approaches new “equilibrium” proliferation characteristics via damped periodic transients, the damping being characterized by λ. Thus, the response time of the system, T̄/λ, is as basic a parameter of the system as the cell-cycle time. PMID:5696217

  19. Mitochondrial Regulation of Cell Cycle and Proliferation

    PubMed Central

    Antico Arciuch, Valeria Gabriela; Elguero, María Eugenia; Poderoso, Juan José

    2012-01-01

    Abstract Eukaryotic mitochondria resulted from symbiotic incorporation of α-proteobacteria into ancient archaea species. During evolution, mitochondria lost most of the prokaryotic bacterial genes and only conserved a small fraction including those encoding 13 proteins of the respiratory chain. In this process, many functions were transferred to the host cells, but mitochondria gained a central role in the regulation of cell proliferation and apoptosis, and in the modulation of metabolism; accordingly, defective organelles contribute to cell transformation and cancer, diabetes, and neurodegenerative diseases. Most cell and transcriptional effects of mitochondria depend on the modulation of respiratory rate and on the production of hydrogen peroxide released into the cytosol. The mitochondrial oxidative rate has to remain depressed for cell proliferation; even in the presence of O2, energy is preferentially obtained from increased glycolysis (Warburg effect). In response to stress signals, traffic of pro- and antiapoptotic mitochondrial proteins in the intermembrane space (B-cell lymphoma-extra large, Bcl-2-associated death promoter, Bcl-2 associated X-protein and cytochrome c) is modulated by the redox condition determined by mitochondrial O2 utilization and mitochondrial nitric oxide metabolism. In this article, we highlight the traffic of the different canonical signaling pathways to mitochondria and the contributions of organelles to redox regulation of kinases. Finally, we analyze the dynamics of the mitochondrial population in cell cycle and apoptosis. Antioxid. Redox Signal. 16, 1150–1180. PMID:21967640

  20. Cell proliferation inhibition in reduced gravity

    NASA Technical Reports Server (NTRS)

    Moos, P. J.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Extended durations of spaceflight have been shown to be deleterious on an organismic level; however, mechanisms underlying cellular sensitivity to the gravitational environment remain to be elucidated. The majority of the gravitational studies to date indicates that cell regulatory pathways may be influenced by their gravitational environment. Still, few cell biology experiments have been performed in space flight and even fewer experiments have been repeated on subsequent flights. With flight opportunities on STS-50, 54, and 57, Sf9 cells were flown in the BioServe Fluids Processing Apparatus and cell proliferation was measured with and without exposure to a cell regulatory sialoglycopeptide (CeReS) inhibitor. Results from these flights indicate that the Sf9 cells grew comparable to ground controls, that the CeReS inhibitor bound to its specific receptor, and that its signal transduction cascade was not gravity sensitive.

  1. Dopamine depletion impairs precursor cell proliferation in Parkinson disease.

    PubMed

    Höglinger, Günter U; Rizk, Pamela; Muriel, Marie P; Duyckaerts, Charles; Oertel, Wolfgang H; Caille, Isabelle; Hirsch, Etienne C

    2004-07-01

    Cerebral dopamine depletion is the hallmark of Parkinson disease. Because dopamine modulates ontogenetic neurogenesis, depletion of dopamine might affect neural precursors in the subependymal zone and subgranular zone of the adult brain. Here we provide ultrastructural evidence showing that highly proliferative precursors in the adult subependymal zone express dopamine receptors and receive dopaminergic afferents. Experimental depletion of dopamine in rodents decreases precursor cell proliferation in both the subependymal zone and the subgranular zone. Proliferation is restored completely by a selective agonist of D2-like (D2L) receptors. Experiments with neural precursors from the adult subependymal zone grown as neurosphere cultures confirm that activation of D2L receptors directly increases the proliferation of these precursors. Consistently, the numbers of proliferating cells in the subependymal zone and neural precursor cells in the subgranular zone and olfactory bulb are reduced in postmortem brains of individuals with Parkinson disease. These observations suggest that the generation of neural precursor cells is impaired in Parkinson disease as a consequence of dopaminergic denervation.

  2. Biofilms’ Role in Planktonic Cell Proliferation

    PubMed Central

    Bester, Elanna; Wolfaardt, Gideon M.; Aznaveh, Nahid B.; Greener, Jesse

    2013-01-01

    The detachment of single cells from biofilms is an intrinsic part of this surface-associated mode of bacterial existence. Pseudomonas sp. strain CT07gfp biofilms, cultivated in microfluidic channels under continuous flow conditions, were subjected to a range of liquid shear stresses (9.42 mPa to 320 mPa). The number of detached planktonic cells was quantified from the effluent at 24-h intervals, while average biofilm thickness and biofilm surface area were determined by confocal laser scanning microscopy and image analysis. Biofilm accumulation proceeded at the highest applied shear stress, while similar rates of planktonic cell detachment was maintained for biofilms of the same age subjected to the range of average shear rates. The conventional view of liquid-mediated shear leading to the passive erosion of single cells from the biofilm surface, disregards the active contribution of attached cell metabolism and growth to the observed detachment rates. As a complement to the conventional conceptual biofilm models, the existence of a biofilm surface-associated zone of planktonic cell proliferation is proposed to highlight the need to expand the traditional perception of biofilms as promoting microbial survival, to include the potential of biofilms to contribute to microbial proliferation. PMID:24201127

  3. Scatter hoarding and hippocampal cell proliferation in Siberian chipmunks.

    PubMed

    Pan, Y; Li, M; Yi, X; Zhao, Q; Lieberwirth, C; Wang, Z; Zhang, Z

    2013-01-01

    Food hoarding, especially scatter hoarding and retrieving food caches, requires spatial learning and memory and is an adaptive behavior important for an animal's survival and reproductive success. In the present study, we examined the effects of hoarding behavior on cell proliferation and survival in the hippocampus of male and female Siberian chipmunks (Tamias sibiricus). We found that chipmunks in a semi-natural enclosure displayed hoarding behavior with large individual variations. Males ate more scatter-hoarded seeds than females. In addition, the display of hoarding behavior was associated with increased cell proliferation in the hippocampus and this increase occurred in a brain region-specific manner. These data provide further evidence to support the notion that new cells in the adult hippocampus are affected by learning and memory tasks and may play an important role in adaptive behavior.

  4. Predators inhibit brain cell proliferation in natural populations of electric fish, Brachyhypopomus occidentalis.

    PubMed

    Dunlap, Kent D; Tran, Alex; Ragazzi, Michael A; Krahe, Rüdiger; Salazar, Vielka L

    2016-02-10

    Compared with laboratory environments, complex natural environments promote brain cell proliferation and neurogenesis. Predators are one important feature of many natural environments, but, in the laboratory, predatory stimuli tend to inhibit brain cell proliferation. Often, laboratory predatory stimuli also elevate plasma glucocorticoids, which can then reduce brain cell proliferation. However, it is unknown how natural predators affect cell proliferation or whether glucocorticoids mediate the neurogenic response to natural predators. We examined brain cell proliferation in six populations of the electric fish, Brachyhypopomus occidentalis, exposed to three forms of predator stimuli: (i) natural variation in the density of predatory catfish; (ii) tail injury, presumably from predation attempts; and (iii) the acute stress of capture. Populations with higher predation pressure had lower density of proliferating (PCNA+) cells, and fish with injured tails had lower proliferating cell density than those with intact tails. However, plasma cortisol did not vary at the population level according to predation pressure or at the individual level according to tail injury. Capture stress significantly increased cortisol, but only marginally decreased cell proliferation. Thus, it appears that the presence of natural predators inhibits brain cell proliferation, but not via mechanisms that depend on changes in basal cortisol levels. This study is the first demonstration of predator-induced alteration of brain cell proliferation in a free-living vertebrate.

  5. Endothelial cells regulate the proliferation of monocytes in vitro.

    PubMed

    Pakala, R; Benedict, C R

    1999-11-01

    Monocytes (MPhis) are among the first cells to accumulate in early atherosclerotic lesions and generally are believed to be incapable of proliferation. However, recent studies indicate that the number of MPhis in atherosclerotic lesion may increase due to induction of local proliferation. Since proliferation of hematopoietic lineage cells is strongly influenced by interaction with neighboring cell types, we examined the ability of vascular endothelial cells (EC), smooth muscle cells or fibroblasts to stimulate MPhi proliferation. In this study, we show that only when seeded at high densities MPhis could proliferate in culture. However, when contact co-cultured with EC, MPhis proliferated at a higher rate (260% on day 6) than those cultured alone or co-cultured with smooth muscle cells or fibroblasts. Endothelial cells could stimulate the proliferation of MPhis even at non-proliferating densities. Only EC that were growth arrested or in lag phase could induce MPhi proliferation, whereas those in the exponential proliferating phase were non-stimulatory. Conditioned medium prepared from EC in growth arrested or lag phase failed to stimulate MPhi proliferation. Similarly physical separation of MPhis from EC also resulted in no proliferation. These results suggest that EC induced MPhi proliferation is contact dependent and no soluble factors are involved in this induction. This EC induced MPhi proliferation may have a profound effect on the rate of progression of atherosclerosis.

  6. The PSORS1 locus gene CCHCR1 affects keratinocyte proliferation in transgenic mice.

    PubMed

    Tiala, Inkeri; Wakkinen, Janica; Suomela, Sari; Puolakkainen, Pauli; Tammi, Raija; Forsberg, Sofi; Rollman, Ola; Kainu, Kati; Rozell, Björn; Kere, Juha; Saarialho-Kere, Ulpu; Elomaa, Outi

    2008-04-01

    The CCHCR1 gene (Coiled-Coil alpha-Helical Rod protein 1) within the major psoriasis susceptibility locus PSORS1 is a plausible candidate gene for the risk effect. We have previously generated transgenic mice overexpressing either the psoriasis-associated risk allele CCHCR1*WWCC or the normal allele of CCHCR1. All transgenic CCHCR1 mice appeared phenotypically normal, but exhibited altered expression of genes relevant to the pathogenesis of psoriasis, including upregulation of hyperproliferation markers keratins 6, 16 and 17. Here, we challenged the skin of CCHCR1 transgenic mice with wounding or 12-O-tetradecanoyl-13-acetate (TPA), treatments able to induce epidermal hyperplasia and proliferation that both are hallmarks of psoriasis. These experiments revealed that CCHCR1 regulates keratinocyte proliferation. Early wound healing on days 1 and 4 was delayed, and TPA-induced epidermal hyperproliferation was less pronounced in mice with the CCHCR1*WWCC risk allele than in mice with the normal allele or in wild-type animals. Finally, we demonstrated that overexpression of CCHCR1 affects basal keratinocyte proliferation in mice; CCHCR1*WWCC mice had less proliferating keratinocytes than the non-risk allele mice. Similarly, keratinocytes isolated from risk allele mice proliferated more slowly in culture than wild-type cells when measured by BrdU labeling and ELISA. Our data show that CCHCR1 may function as a negative regulator of keratinocyte proliferation. Thus, aberrant function of CCHCR1 may lead to abnormal keratinocyte proliferation which is a key feature of psoriatic epidermis.

  7. SCTR regulates cell cycle-related genes toward anti-proliferation in normal breast cells while having pro-proliferation activity in breast cancer cells.

    PubMed

    Kang, Seongeun; Kim, Byungtak; Kang, Han-Sung; Jeong, Gookjoo; Bae, Hansol; Lee, Hyunkyung; Lee, Seungyeon; Kim, Sun Jung

    2015-11-01

    Secretin receptor (SCTR), the G-protein coupled receptor (GPCR) for secretin, has been observed to be upregulated in a few tumor types while downregulated in others, promoting or suppressing the proliferation of tumor cells, respectively. However, little is known about the molecular regulatory mechanism of dysregulation in cancer. In the present study, an analysis of the biological pathways affected by methylation in breast cancer using the methylome databases revealed that GPCRs played a major part in the affected pathway. SCTR, one of the dysregulated GPCRs, showed hypermethylation (p<0.01) and downregulation (p<0.05) in breast cancer tissues. Pathway analysis after the downregulation of SCTR by siRNA in MCF-10A cells identified the G2/M stage checkpoint as the top-scored pathway. Cell cycle-related genes were all upregulated or downregulated suppressing cell proliferation. However, the overexpression of SCTR in MCF-7 cells led to a 35% increase of the cell proliferation index and 2.1-fold increase of cellular migration. Our findings indicate that SCTR suppresses the proliferation of normal breast cells, while the gene stimulates the proliferation and migration of cancer cells being downregulated by promoter methylation.

  8. Beyond cell proliferation in avian facial morphogenesis

    PubMed Central

    Linde-Medina, Marta; Hallgrímsson, Benedikt; Marcucio, Ralph

    2016-01-01

    The upper jaw in vertebrates forms from several prominences that arise around the stomodeum or primitive mouth. These prominences undergo coordinated growth and morphogenesis to fuse and form the face. Undirected, regionalized cell proliferation is thought to be the driving force behind the morphogenesis of the facial prominences. However, recent findings suggest that directed cell behaviors in the mesenchyme (e.g., directed cell division, directed cell movement, convergent extension) might be required for successful face formation. Here we discuss the evidence for this view and how directed behaviors may interact with the basement membrane to regulate morphogenesis of the facial region. We believe that future research in these largely unexplored areas could significantly impact our understanding of facial morphogenesis. PMID:26637960

  9. Plant cell proliferation inside an inorganic host.

    PubMed

    Perullini, Mercedes; Rivero, María Mercedes; Jobbágy, Matías; Mentaberry, Alejandro; Bilmes, Sara A

    2007-01-10

    In recent years, much attention has been paid to plant cell culture as a tool for the production of secondary metabolites and the expression of recombinant proteins. Plant cell immobilization offers many advantages for biotechnological processes. However, the most extended matrices employed, such as calcium-alginate, cannot fully protect entrapped cells. Sol-gel chemistry of silicates has emerged as an outstanding strategy to obtain biomaterials in which living cells are truly protected. This field of research is rapidly developing and a large number of bacteria and yeast-entrapping ceramics have already been designed for different applications. But even mild thermal and chemical conditions employed in sol-gel synthesis may result harmful to cells of higher organisms. Here we present a method for the immobilization of plant cells that allows cell growth at cavities created inside a silica matrix. Plant cell proliferation was monitored for a 6-month period, at the end of which plant calli of more than 1 mm in diameter were observed inside the inorganic host. The resulting hybrid device had good mechanical stability and proved to be an effective barrier against biological contamination, suggesting that it could be employed for long-term plant cell entrapment applications.

  10. Cell Proliferation, Cell Death, and Size Regulation

    DTIC Science & Technology

    2000-10-01

    predicted to encode a novel 582 amino acid protein, perhaps interacting with molybdopterin. It is possible that the pie gene encodes a novel enzyme protecting against cell death during growth and development.

  11. Proliferating cell nuclear antigen: a proteomics view.

    PubMed

    Naryzhny, S N

    2008-11-01

    Proliferating cell nuclear antigen (PCNA), a cell cycle marker protein, is well known as a DNA sliding clamp for DNA polymerase delta and as an essential component for eukaryotic chromosomal DNA replication and repair. Due to its mobility inside nuclei, PCNA is dynamically presented in a soluble or chromatin-associated form. The heterogeneity and specific modifications of PCNA may reflect its multiple functions and the presence of many binding partners in the cell. The recent proteomics approaches applied to characterizing PCNA interactions revealed multiple PCNA partners with a wide spectrum of activity and unveiled the possible existence of new PCNA functions. Since more than 100 PCNA-interacting proteins and several PCNA modifications have already been reported, a proteomics point of view seems exactly suitable to better understand the role of PCNA in cellular functions.

  12. Cancer cell proliferation is inhibited by specific modulation frequencies

    PubMed Central

    Zimmerman, J W; Pennison, M J; Brezovich, I; Yi, N; Yang, C T; Ramaker, R; Absher, D; Myers, R M; Kuster, N; Costa, F P; Barbault, A; Pasche, B

    2012-01-01

    Background: There is clinical evidence that very low and safe levels of amplitude-modulated electromagnetic fields administered via an intrabuccal spoon-shaped probe may elicit therapeutic responses in patients with cancer. However, there is no known mechanism explaining the anti-proliferative effect of very low intensity electromagnetic fields. Methods: To understand the mechanism of this novel approach, hepatocellular carcinoma (HCC) cells were exposed to 27.12 MHz radiofrequency electromagnetic fields using in vitro exposure systems designed to replicate in vivo conditions. Cancer cells were exposed to tumour-specific modulation frequencies, previously identified by biofeedback methods in patients with a diagnosis of cancer. Control modulation frequencies consisted of randomly chosen modulation frequencies within the same 100 Hz–21 kHz range as cancer-specific frequencies. Results: The growth of HCC and breast cancer cells was significantly decreased by HCC-specific and breast cancer-specific modulation frequencies, respectively. However, the same frequencies did not affect proliferation of nonmalignant hepatocytes or breast epithelial cells. Inhibition of HCC cell proliferation was associated with downregulation of XCL2 and PLP2. Furthermore, HCC-specific modulation frequencies disrupted the mitotic spindle. Conclusion: These findings uncover a novel mechanism controlling the growth of cancer cells at specific modulation frequencies without affecting normal tissues, which may have broad implications in oncology. PMID:22134506

  13. Notch1, Notch2, and Epstein-Barr virus-encoded nuclear antigen 2 signaling differentially affects proliferation and survival of Epstein-Barr virus-infected B cells.

    PubMed

    Kohlhof, Hella; Hampel, Franziska; Hoffmann, Reinhard; Burtscher, Helmut; Weidle, Ulrich H; Hölzel, Michael; Eick, Dirk; Zimber-Strobl, Ursula; Strobl, Lothar J

    2009-05-28

    The canonical mode of transcriptional activation by both the Epstein-Barr viral protein, Epstein-Barr virus-encoded nuclear antigen 2 (EBNA2), and an activated Notch receptor (Notch-IC) requires their recruitment to RBPJ, suggesting that EBNA2 uses the Notch pathway to achieve B-cell immortalization. To gain further insight into the biologic equivalence between Notch-IC and EBNA2, we performed a genome-wide expression analysis, revealing that Notch-IC and EBNA2 exhibit profound differences in the regulation of target genes. Whereas Notch-IC is more potent in regulating genes associated with differentiation and development, EBNA2 is more potent in inducing viral and cellular genes involved in proliferation, survival, and chemotaxis. Because both EBNA2 and Notch-IC induced the expression of cell cycle-associated genes, we analyzed whether Notch1-IC or Notch2-IC can replace EBNA2 in B-cell immortalization. Although Notch-IC could drive quiescent B cells into the cell cycle, B-cell immortalization was not maintained, partially due to an increased apoptosis rate in Notch-IC-expressing cells. Expression analysis revealed that both EBNA2 and Notch-IC induced the expression of proapoptotic genes, but only in EBNA2-expressing cells were antiapoptotic genes strongly up-regulated. These findings suggest that Notch signaling in B cells and B-cell lymphomas is only compatible with proliferation if pathways leading to antiapototic signals are active.

  14. DNMT1 regulates human endometrial carcinoma cell proliferation

    PubMed Central

    Wang, Xinjing; Li, Bilan

    2017-01-01

    Endometrial carcinoma (EC) is the most common gynecologic malignancy, but the molecular events involved in the development and progression of EC remain unclear. This study aimed to investigate the role of DNA methyltransferase 1 (DNMT1), a member of DNA methyltransferases, in EC. AN3CA cells were transfected with DNMT1 siRNA. The proliferation, cell cycle, and apoptosis of AN3CA cells were evaluated by Cell Counting Kit-8 (CCK-8) assay and flow cytometry. The expression of related genes was detected by polymerase chain reaction and Western blot analysis. Knockdown of DNMT1 inhibited the proliferation, induced apoptosis, and G0/G1 phase arrest of AN3CA cells. Furthermore, knockdown of DNMT1 upregulated the expression of nuclear factor kappa-B-inhibitor alpha (NF-κBIA) and Bax and downregulated the expression of Bcl-2 and CCND1/2 in AN3CA cells. In conclusion, this study provides the first evidence that knockdown of DNMT1 affects the expression of cell cycle- and apoptosis-associated proteins in EC cells, suggesting the potential of DNMT1 in EC therapy.

  15. Research Techniques Made Simple: Techniques to Assess Cell Proliferation.

    PubMed

    Romar, George A; Kupper, Thomas S; Divito, Sherrie J

    2016-01-01

    Cell proliferation is commonly assayed in the laboratory for research purposes, but is increasingly used clinically to gauge tumor aggressiveness and potentially guide care. Therefore, both researchers and clinicians should have a basic understanding of techniques used to assess cell proliferation. Multiple cell proliferation assays exist, and the choice of method depends on the laboratory resources available, the types of cells/tissues to be studied, and the specific experimental goals. In this article, we identify four overarching categories of cell proliferation assays that signify various stages of the cell cycle: nucleoside-analog incorporation, cell cycle-associated protein detection, use of cytoplasmic proliferation dyes, and indirect measures of cell proliferation. Each method has strengths and limitations that should guide the dermatology investigator's choice of assay.

  16. Numb-deficient satellite cells have regeneration and proliferation defects

    PubMed Central

    George, Rajani M.; Biressi, Stefano; Beres, Brian J.; Rogers, Erik; Mulia, Amanda K.; Allen, Ronald E.; Rawls, Alan; Rando, Thomas A.; Wilson-Rawls, Jeanne

    2013-01-01

    The adaptor protein Numb has been implicated in the switch between cell proliferation and differentiation made by satellite cells during muscle repair. Using two genetic approaches to ablate Numb, we determined that, in its absence, muscle regeneration in response to injury was impaired. Single myofiber cultures demonstrated a lack of satellite cell proliferation in the absence of Numb, and the proliferation defect was confirmed in satellite cell cultures. Quantitative RT-PCR from Numb-deficient satellite cells demonstrated highly up-regulated expression of p21 and Myostatin, both inhibitors of myoblast proliferation. Transfection with Myostatin-specific siRNA rescued the proliferation defect of Numb-deficient satellite cells. Furthermore, overexpression of Numb in satellite cells inhibited Myostatin expression. These data indicate a unique function for Numb during the initial activation and proliferation of satellite cells in response to muscle injury. PMID:24170859

  17. Calcium channels, external calcium concentration and cell proliferation.

    PubMed

    Borowiec, Anne-Sophie; Bidaux, Gabriel; Pigat, Natascha; Goffin, Vincent; Bernichtein, Sophie; Capiod, Thierry

    2014-09-15

    Evidence for a role for calcium channel proteins in cell proliferation is numerous suggesting that calcium influx is essential in this physiological process. Several studies in the past thirty years have demonstrated that calcium channel expression levels are determinant in cell proliferation. Voltage-gated, store-operated, second messengers and receptor-operated calcium channels have been associated to cell proliferation. However, the relationship between calcium influx and cell proliferation can be uncoupled in transformed and cancer cells, resulting in an external calcium-independent proliferation. Thus, protein expression could be more important than channel function to trigger cell proliferation suggesting that additional channel functions may be responsible to reconcile calcium channel expression and cell proliferation. When needed, external calcium concentration is obviously important for calcium channel function but it also regulates calcium sensing receptor (CaSR) activity. CaSR can up- or down-regulate cell proliferation depending on physiological conditions. CaSR sensitivity to external calcium is within the 0.5 to 5 mM range and therefore, the role of these receptors in cell proliferation must be taken into account. We therefore suggest here that cell proliferation rates could depend on the relative balance between calcium influx and CaSR activation.

  18. Interleukin-1 regulates proliferation and differentiation of oligodendrocyte progenitor cells.

    PubMed

    Vela, José M; Molina-Holgado, Eduardo; Arévalo-Martín, Angel; Almazán, Guillermina; Guaza, Carmen

    2002-07-01

    Interleukin-1 (IL-1) is a pleiotropic cytokine expressed during normal CNS development and in inflammatory demyelinating diseases, but remarkably little is known about its effect on oligodendroglial cells. In this study we explored the role of IL-1beta in oligodendrocyte progenitors and differentiated oligodendrocytes. The effects of IL-1beta were compared to those of IL-1 receptor antagonist, the specific inhibitor of IL-1 activity, since progenitors and differentiated oligodendrocytes produce IL-1beta and express IL-1 receptors. Unlike other proinflammatory cytokines (TNFalpha and IFNgamma), IL-1beta was not toxic for oligodendrocyte lineage cells. However, this cytokine inhibited proliferation of oligodendrocyte progenitors in the presence of growth factors (PDGF plus bFGF). This was evidenced by a significant decrease in both cells incorporating bromodeoxyuridine (45%) and total cell numbers (57%) after 6 days of treatment. Interestingly, IL-1beta blocked proliferation at the late progenitor/prooligodendrocyte (O4+) stage but did not affect proliferation of early progenitors (A2B5+). Inhibition of proliferation paralleled with promotion of differentiation, as revealed by the increased percentage of R-mab+ cells (6.7-fold). Moreover, when oligodendrocyte progenitors were allowed to differentiate in the absence of growth factors, treatment with IL-1beta promoted maturation to the MBP+ stage (4.2-fold) and survival of differentiating oligodendrocytes (2.1-fold). Regarding intracellular signaling, IL-1beta activated the p38 mitogen-activated protein kinase (MAPK) but not the p42/p44 MAPK and, when combined with growth factors, intensified p38 activation but inhibited the growth-factor-induced p42/p44 activation. IL-1beta also induced a time-dependent inhibition of PFGF-Ralpha gene expression. These results support a role for IL-1beta in promoting mitotic arrest and differentiation of oligodendrocyte progenitors as well as maturation and survival of differentiating

  19. A selective inhibitor of cell proliferation from normal serum.

    PubMed Central

    Harrington, W N; Godman, G C

    1980-01-01

    A factor in normal serum that selectively and reversibly inhibits proliferation of cells in culture has been enriched 160-fold from calf serum by sequential ammonium sulfate precipitation, gel filtration, and lectin-affinity chromatography. DNA synthesis of normal (but not transformed) rat hepatocytes, human lymphoblast lines, and mitogen-stimulated murine spleen cells is inhibited by greater than 90%, and Vero, murine myeloma, MELC, and a human colon carcinoma cell line to a lesser extent. Growth of other cell lines tested was not affected. Responsive cells are arrested apparently in G1 by this inhibitor, the effect of which is maximal by 24 hr and is spontaneously reversible thereafter unless it is renewed. The active fraction is a protein that migrates with the alpha 2-globulins; it is not a lipoprotein, and it is of high apparent molecular weight. PMID:6928635

  20. Endogenous Hydrogen Sulfide Enhances Cell Proliferation of Human Gastric Cancer AGS Cells.

    PubMed

    Sekiguchi, Fumiko; Sekimoto, Teruki; Ogura, Ayaka; Kawabata, Atsufumi

    2016-01-01

    Hydrogen sulfide (H2S), the third gasotransmitter, is endogenously generated by certain H2S synthesizing enzymes, including cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS) from L-cysteine in the mammalian body. Several studies have shown that endogenous and exogenous H2S affects the proliferation of cancer cells, although the effects of H2S appear to vary with cell type, being either promotive or suppressive. In the present study, we determined whether endogenously formed H2S regulates proliferation in human gastric cancer AGS cells. CSE, but not CBS, was expressed in AGS cells. CSE inhibitors, DL-propargylglycine (PPG) and β-cyano-L-alanine (BCA), significantly suppressed the proliferation of AGS cells in a concentration-dependent manner. CSE inhibitors did not increase lactate dehydrogenase (LDH) release in the same concentration range. The inhibitory effects of PPG and BCA on cell proliferation were reversed by repetitive application of NaHS, a donor of H2S. Interestingly, nuclear condensation and fragmentation were detected in AGS cells treated with PPG or BCA. These results suggest that endogenous H2S produced by CSE may contribute to the proliferation of gastric cancer AGS cells, most probably through anti-apoptotic actions.

  1. CP27 affects viability, proliferation, attachment and gene expression in embryonic fibroblasts.

    PubMed

    Luan, X; Diekwisch, T G H

    2002-08-01

    CP27 is a gene that has been cloned from an E11 early embryonic library and has been suggested to mediate early organogenesis (Diekwisch et al., 1999, Gene 235, 19). We have hypothesized that CP27 exhibits its effects on organogenesis by affecting individual cell function. Based on the CP27 expression pattern we have selected the CP27 expressing embryonic fibroblast cell line BALB/c 3T3 to determine the effects of CP27 on cell function. CP27 loss of function strategies were performed by adding 5, 12.5 or 25 micro g/ml anti-CP27 antibody to cultured BALB/c 3T3 cells and comparing the results to controls in which identical concentrations of rabbit serum were added to the culture medium. Other controls included an antibody against another extracellular matrix protein amelogenin (negative control) and anti-CP27 antibodies directed against other areas of the CP27 molecule (positive control). Following cell culture, cell viability, apoptosis, cell proliferation, cell shape, cellular attachment and fibronectin matrix production were assayed using MTT colourimetric assay, BrdU staining, morphometry, immunostaining and western blot analysis. Block of CP27 function using an antibody strategy resulted in the following significant changes: (i) reduced viability, (ii) increased number of apoptotic cells, (iii) reduced proliferation, (iv) alterations in cell shape, (v) loss of attachment, and (vi) reduction in fibronectin matrix production. There was also a redistribution in fibronectin matrix organization demonstrated by immunohistochemistry. We conclude that CP27 plays an important role in the maintance of normal cell function and that CP27 block leads to significant changes in cellular behaviour.

  2. Serglycin in Quiescent and Proliferating Primary Endothelial Cells

    PubMed Central

    Reine, Trine M.; Vuong, Tram T.; Rutkovskiy, Arkady; Meen, Astri J.; Vaage, Jarle; Jenssen, Trond G.; Kolset, Svein O.

    2015-01-01

    Proteoglycans are fundamental components of the endothelial barrier, but the functions of the proteoglycan serglycin in endothelium are less described. Our aim was to describe the roles of serglycin in processes relevant for endothelial dysfunction. Primary human umbilical vein endothelial cells (HUVEC) were cultured in vitro and the expression of proteoglycans was investigated. Dense cell cultures representing the quiescent endothelium coating the vasculature was compared to sparse activated cell cultures, relevant for diabetes, cancer and cardiovascular disease. Secretion of 35S- proteoglycans increased in sparse cultures, and we showed that serglycin is a major component of the cell-density sensitive proteoglycan population. In contrast to the other proteoglycans, serglycin expression and secretion was higher in proliferating compared to quiescent HUVEC. RNAi silencing of serglycin inhibited proliferation and wound healing, and serglycin expression and secretion was augmented by hypoxia, mechanical strain and IL-1β induced inflammation. Notably, the secretion of the angiogenic chemokine CCL2 resulting from IL-1β activation, was increased in serglycin knockdown cells, while angiopoietin was not affected. Both serglycin and CCL2 were secreted predominantly to the apical side of polarized HUVEC, and serglycin and CCL2 co-localized both in perinuclear areas and in vesicles. These results suggest functions for serglycin in endothelial cells trough interactions with partner molecules, in biological processes with relevance for diabetic complications, cardiovascular disease and cancer development. PMID:26694746

  3. Alkylindole-sensitive receptors modulate microglial cell migration and proliferation

    PubMed Central

    Fung, Susan; Cherry, Allison E.; Xu, Cong; Stella, Nephi

    2015-01-01

    Ligands targeting G protein-coupled receptors (GPCR) expressed by microglia have been shown to regulate distinct components of their activation process, including cell proliferation, migration and differentiation into M1 or M2 phenotypes. Cannabinoids, including the active component of the Cannabis plant, tetrahydrocannabinol (THC), and the synthetic alkylindole (AI) compound, WIN55212-2 (WIN-2), activate two molecularly identified GPCRs: CB1 and CB2. Previous studies reported that WIN-2 activates an additional unknown GPCR that is not activated by plant-derived cannabinoids, and evidence indicates that microglia express these receptors. Detailed studies on the role of AI-sensitive receptors in microglial cell activation were difficult as no selective pharmacological tools were available. Here, three newly-developed AI analogues allowed us to determine if microglia express AI-sensitive receptors and if so, study how they regulate the microglial cell activation process. We found that mouse microglia in primary culture express functional AI-sensitive receptors as measured by radioligand binding and changes in intracellular cAMP levels, and that these receptors control both basal and ATP-stimulated migration. AI analogues inhibit cell proliferation stimulated by macrophage-colony stimulating factor (M-CSF) without affecting basal cell proliferation. Remarkably, AI analogues do not control the expression of effector proteins characteristic of M1 or M2 phenotypes; yet activating microglia with M1 and M2 cytokines reduces the microglial response to AI analogues. Our results suggest that microglia express functional AI-sensitive receptors that control select components of their activation process. Agonists of these novel targets might represent a novel class of therapeutics to influence the microglial cell activation process. PMID:25914169

  4. Cell proliferation and migration in silk fibroin 3D scaffolds.

    PubMed

    Mandal, Biman B; Kundu, Subhas C

    2009-05-01

    Pore architecture in 3D polymeric scaffolds is known to play a critical role in tissue engineering as it provides the vital framework for the seeded cells to organize into a functioning tissue. In this report, we investigated the effects of different freezing temperature regimes on silk fibroin protein 3D scaffold pore microstructure. The fabricated scaffolds using freeze-dry technique were used as a 3D model to monitor cell proliferation and migration. Pores of 200-250microm diameter were formed by slow cooling at temperatures of -20 and -80 degrees C but were found to be limited in porosity and pore interconnectivity as observed through scanning electron microscopic images. In contrast, highly interconnected pores with 96% porosity were observed when silk solutions were rapidly frozen at -196 degrees C. A detailed study was conducted to assess the affect of pore size, porosity and interconnectivity on human dermal fibroblast cell proliferation and migration on these 3D scaffolds using confocal microscopy. The cells were observed to migrate within the scaffold interconnectivities and were found to reach scaffold periphery within 28 days of culture. Confocal images further confirmed normal cell attachment and alignment of actin filaments within the porous scaffold matrix with well-developed nuclei. This study indicates rapid freeze-drying technique as an alternative method to fabricate highly interconnected porous scaffolds for developing functional 3D silk fibroin matrices for potential tissue engineering, biomedical and biotechnological applications.

  5. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    SciTech Connect

    Zhang, Yu; Cheng, Jung-Chien; Huang, He-Feng; Leung, Peter C.K.

    2013-11-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells.

  6. Possible involvement of queuine in regulation of cell proliferation.

    PubMed

    Pathak, Chandramani; Jaiswal, Yogesh K; Vinayak, Manjula

    2007-01-01

    An increase in cell number is one of the most prominent characteristics of cancer cells. This may be caused by an increase in cell proliferation or decrease in cell death. Queuine is one of the modified base which is found at first anticodon position of specific tRNAs. It is ubiquitously present throughout the living system except mycoplasma and yeast. The tRNAs of Q-family are completely modified to Q-tRNAs in terminally differentiated somatic cells, however hypomodification of Q-tRNA is closely associated with cell proliferation and malignancy. Queuine participates at various cellular functions such as regulation of cell proliferation, cell signaling and alteration in the expression of growth associated proto-oncogenes. Like other proto-oncogenes bcl2 is known to involve in cell survival by inhibiting apoptosis. Queuine or Q-tRNA is suggested to inhibit cell proliferation but the mechanism of regulation of cell proliferation by queuine or Q-tRNA is not well understood. Therefore, in the present study regulation in cell proliferation by queuine in vivo and in vitro as well as the expression of cell death regulatory protein Bcl2 are investigated. For this DLAT cancerous mouse, U87 cell line and HepG2 cell line are treated with different concentrations of queuine and the effect of queuine on cell proliferation and apoptosis are studied. The results indicate that queuine down regulates cell proliferation and expression of Bcl2 protein, suggesting that queuine promotes cell death and participates in the regulation of cell proliferation.

  7. Skin cell proliferation stimulated by microneedles.

    PubMed

    Liebl, Horst; Kloth, Luther C

    2012-03-01

    A classical wound may be defined as a disruption of tissue integrity. Wounds, caused by trauma from accidents or surgery, that close via secondary intention rely on the biological phases of healing, i.e., hemostasis, inflammation, proliferation, and remodeling (HIPR). Depending on the wound type and severity, the inflammation phase begins immediately after injury and may last for an average of 7-14 days. Concurrent with the inflammation phase or slightly delayed, cell proliferation is stimulated followed by the activation of the remodeling (maturation) phase. The latter phase can last as long as 1 year or more, and the final healed state is represented by a scar tissue, a cross-linked collagen formation that usually aligns collagen fibers in a single direction. One may assume that skin microneedling that involves the use of dozens or as many as 200 needles that limit penetration to 1.5 mm over 1 cm(2) of skin would cause trauma and bleeding followed by the classical HIPR. However, this is not the case or at least the HIPR phases are significantly curtailed and healing never ends in a scar formation. Conversely dermabrasion used in aesthetic medicine for improving skin quality is based on "ablation" (destruction or wounding of superficial skin layers), which requires several weeks for healing that involves formation of new skin layers. Such procedures provoke an acute inflammatory response. We believe that a less intense inflammatory response occurs following microneedle perforation of the skin. However, the mechanism of action of microneedling appears to be different. Here we review the potential mechanisms by which microneedling of the skin facilitates skin repair without scarring after the treatment of superficial burns, acne, hyperpigmentation, and the non-advancing periwound skin surrounding the chronic ulcerations of the integument.

  8. Skin Cell Proliferation Stimulated by Microneedles

    PubMed Central

    Liebl, Horst; Kloth, Luther C.

    2012-01-01

    A classical wound may be defined as a disruption of tissue integrity. Wounds, caused by trauma from accidents or surgery, that close via secondary intention rely on the biological phases of healing, i.e., hemostasis, inflammation, proliferation, and remodeling (HIPR). Depending on the wound type and severity, the inflammation phase begins immediately after injury and may last for an average of 7–14 days. Concurrent with the inflammation phase or slightly delayed, cell proliferation is stimulated followed by the activation of the remodeling (maturation) phase. The latter phase can last as long as 1 year or more, and the final healed state is represented by a scar tissue, a cross-linked collagen formation that usually aligns collagen fibers in a single direction. One may assume that skin microneedling that involves the use of dozens or as many as 200 needles that limit penetration to 1.5 mm over 1 cm2 of skin would cause trauma and bleeding followed by the classical HIPR. However, this is not the case or at least the HIPR phases are significantly curtailed and healing never ends in a scar formation. Conversely dermabrasion used in aesthetic medicine for improving skin quality is based on “ablation” (destruction or wounding of superficial skin layers), which requires several weeks for healing that involves formation of new skin layers. Such procedures provoke an acute inflammatory response. We believe that a less intense inflammatory response occurs following microneedle perforation of the skin. However, the mechanism of action of microneedling appears to be different. Here we review the potential mechanisms by which microneedling of the skin facilitates skin repair without scarring after the treatment of superficial burns, acne, hyperpigmentation, and the non-advancing periwound skin surrounding the chronic ulcerations of the integument. PMID:24527373

  9. β-Lactoglobulin Influences Human Immunity and Promotes Cell Proliferation

    PubMed Central

    Tai, Chun San; Chen, Yi Yun

    2016-01-01

    β-Lactoglobulin (LG) is suspected to enhance or modulate human immune responses. Moreover, LG is also hypothesized to increase human cell proliferation. However, these potential functions of LG have not been directly or thoroughly addressed. In this study, we demonstrated that LG is a potent stimulator of cell proliferation using a hybridoma cell (a splenocyte fused with a myeloma cell) model. LG's ability to promote cell proliferation was lost when the protein is denatured. To further investigate the influence of LG's conformation on cell proliferation, we chemically modified LG by either carboxymethylation (CM) or acetylation and observed significantly reduced cell proliferation when the protein structure was altered. Furthermore, we proved that LG enhances cell proliferation via receptor-mediated membrane IgM receptor. These data indicated that nondenatured LG is the major component in milk that modulates cell proliferation. Collectively, our study showed that LG plays a key role in enhancing immune responses by promoting cell proliferation through IgM receptor. PMID:27957499

  10. Satellite cell proliferation in adult skeletal muscle

    NASA Technical Reports Server (NTRS)

    Booth, Frank W. (Inventor); Thomason, Donald B. (Inventor); Morrison, Paul R. (Inventor); Stancel, George M. (Inventor)

    1995-01-01

    Novel methods of retroviral-mediated gene transfer for the in vivo corporation and stable expression of eukaryotic or prokaryotic foreign genes in tissues of living animals is described. More specifically, methods of incorporating foreign genes into mitotically active cells are disclosed. The constitutive and stable expression of E. coli .beta.-galactosidase gene under the promoter control of the Moloney murine leukemia virus long terminal repeat is employed as a particularly preferred embodiment, by way of example, establishes the model upon which the incorporation of a foreign gene into a mitotically-active living eukaryotic tissue is based. Use of the described methods in therapeutic treatments for genetic diseases, such as those muscular degenerative diseases, is also presented. In muscle tissue, the described processes result in genetically-altered satellite cells which proliferate daughter myoblasts which preferentially fuse to form a single undamaged muscle fiber replacing damaged muscle tissue in a treated animal. The retroviral vector, by way of example, includes a dystrophin gene construct for use in treating muscular dystrophy. The present invention also comprises an experimental model utilizable in the study of the physiological regulation of skeletal muscle gene expression in intact animals.

  11. Vascular endothelial growth factor directly stimulates tumour cell proliferation in non-small cell lung cancer.

    PubMed

    Devery, Aoife M; Wadekar, Rekha; Bokobza, Sivan M; Weber, Anika M; Jiang, Yanyan; Ryan, Anderson J

    2015-09-01

    Vascular endothelial growth factor (VEGF) is a key stimulator of physiological and pathological angiogenesis. VEGF signals primarily through VEGF receptor 2 (VEGFR2), a receptor tyrosine kinase whose expression is found predominantly on endothelial cells. The purpose of this study was to determine the role of VEGFR2 expression in NSCLC cells. NSCLC cells and tissue sections were stained for VEGFR2 expression by immunohistochemistry (IHC). Immunoblotting and ELISA were used to determine the activation and inhibition of VEGFR2 and its downstream signalling pathways. Five-day proliferation assays were carried out in the presence or absence of VEGF. IHC analysis of NSCLC demonstrated tumour cell VEGFR2 expression in 20% of samples. Immunoblot analysis showed expression of VEGFR2 protein in 3/8 NSCLC cell lines that correlated with VEGFR2 mRNA expression levels. VEGF-dependent VEGFR2 activation was apparent in NSCLC cells, and was associated with increased tumor cell proliferation. Cediranib treatment or siRNA against VEGFR2 inhibited VEGF-dependent increases in cell proliferation. Inhibition of VEGFR2 tyrosine kinase activity using cediranib was more effective than inhibition of AKT (MK2206) or MEK (AZD6244) for overcoming VEGFR2-driven cell proliferation. VEGF treatment did not affect cell survival following treatment with radiation, cisplatin, docetaxel or gemcitabine. Our data suggest that a subset of NSCLC tumour cells express functional VEGFR2 which can act to promote VEGF-dependent tumour cell growth. In this tumour subset, therapies targeting VEGFR2 signalling, such as cediranib, have the potential to inhibit both tumour cell proliferation and angiogenesis.

  12. 50 Hz sinusoidal magnetic fields do not affect human lymphocyte activation and proliferation in vitro

    NASA Astrophysics Data System (ADS)

    Capri, Miriam; Mesirca, Pietro; Remondini, Daniel; Carosella, Simona; Pasi, Sara; Castellani, Gastone; Franceschi, Claudio; Bersani, Ferdinando

    2004-12-01

    In the last 30 years, an increasing public concern about the possible harmful effects of electromagnetic fields generated by power lines and domestic appliances has pushed the scientific community to search for a correct and comprehensive answer to this problem. In this work the effects of exposure to 50 Hz sinusoidal magnetic fields, with a magnetic flux density of 0.05 mT and 2.5 mT (peak values), were studied on human peripheral blood mononuclear cells (PBMCs) collected from healthy young and elderly donors. Cell activation and proliferation were investigated by using flow cytometry techniques and 3H-TdR incorporation assays, respectively. The results obtained indicated that exposure to the fields altered neither DNA synthesis nor the capacity of lymphocytes to enter the activation phase and progress into the cell cycle. Thus, the conclusions are that two important functional phases of human lymphocytes, such as activation and proliferation, are not affected by exposures to 50 Hz magnetic fields similar to those found under power lines.

  13. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    SciTech Connect

    Poulsen, Raewyn C. 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. H2A/K pseudogene mutation may promote cell proliferation.

    PubMed

    Guo, Jisheng; Jing, Ruirui; Lv, Xin; Wang, Xiaoyue; Li, Junqiang; Li, Lin; Li, Cuiling; Wang, Daoguang; Bi, Baibing; Chen, Xinjun; Yang, Jing-Hua

    2016-05-01

    Little attention has been paid to the histone H2A/K pseudogene. Results from our laboratory showed that 7 of 10 kidney cancer patients carried a mutant H2A/K pseudogene; therefore, we were interested in determining the relationship between mutant H2A/K and cell proliferation. We used shotgun and label-free proteomics methods to study whether mutant H2A/K lncRNAs affected cell proliferation. Quantitative proteomic analysis indicated that the expression of mutant H2A/K lncRNAs resulted in the upregulation of many oncogenes, which promoted cell proliferation. Further interaction analyses revealed that a proliferating cell nuclear antigen (PCNA)-protein interaction network, with PCNA in the center, contributes to cell proliferation in cells expressing the mutant H2A/K lncRNAs. Western blotting confirmed the critical upregulation of PCNA by mutant H2A/K lncRNA expression. Finally, the promotion of cell proliferation by mutant H2A/K lncRNAs (C290T, C228A and A45G) was confirmed using cell proliferation assays. Although we did not determine the exact mechanism by which the oncogenes were upregulated by the mutant H2A/K lncRNAs, we confirmed that the mutant H2A/K lncRNAs promoted cell proliferation by upregulating PCNA and other oncogenes. The hypothesis that cell proliferation is promoted by the mutant H2A/K lncRNAs was supported by the protein expression and cell proliferation assay results. Therefore, mutant H2A/K lncRNAs may be a new factor in renal carcinogenesis.

  15. The effects of adiponectin and leptin on human endothelial cell proliferation: a live-cell study.

    PubMed

    Alvarez, Granada; Visitación Bartolomé, M; Miana, María; Jurado-López, Raquel; Martín, Ruben; Zuluaga, Pilar; Martinez-Martinez, Ernesto; Nieto, M Luisa; Alvarez-Sala, Luis A; Millán, Jesús; Lahera, Vicente; Cachofeiro, Victoria

    2012-01-01

    The effect of adiponectin and leptin on the proliferation of the human microvascular endothelial cell line (HMEC-1) was studied in the absence or presence of fetal bovine serum (FBS). The participation of extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3-kinase/Akt (PI-3K/Akt) pathways in this effect were evaluated. We studied the effect of both adipokines on the motility, mitosis, proliferation and cell death processes of HMEC-1 cells using live-cell imaging techniques. Adiponectin but not leptin further increased the proliferative effect induced by FBS on HMEC-1. This effect seems to be the consequence of an increase in the mitotic index in adiponectin-treated cells when compared to untreated ones. The presence of either the mitogen-activated protein kinase (MAPK) inhibitor (PD98059), or PI-3K inhibitor (LY294002), reduced the effect of adiponectin in a dose-dependent manner. Neither adipokine was able to affect HMEC-1 proliferation in FBS-free conditions. Duration of mitosis, cell motility and the cell death process were similar in all conditions. These data suggest that adiponectin and leptin exert different effects on endothelial cell function. Adiponectin was able to potentiate proliferation of HMEC-1. This effect involves the activation of both PI3-K/Akt and ERK/MAPK pathways. However, it seems to exert minimal effects on HMEC-1 function in the case of leptin.

  16. Pyruvate kinase isoform expression alters nucleotide synthesis to impact cell proliferation

    PubMed Central

    Lunt, Sophia Y.; Muralidhar, Vinayak; Hosios, Aaron M.; Israelsen, William J.; Gui, Dan Y.; Newhouse, Lauren; Ogrodzinski, Martin; Hecht, Vivian; Xu, Kali; Acevedo, Paula N. Marín; Hollern, Daniel P.; Bellinger, Gary; Dayton, Talya L.; Christen, Stefan; Elia, Ilaria; Dinh, Anh T.; Stephanopoulos, Gregory; Manalis, Scott R.; Yaffe, Michael B.; Andrechek, Eran R.; Fendt, Sarah-Maria; Heiden, Matthew G. Vander

    2014-01-01

    SUMMARY Metabolic regulation influences cell proliferation. The influence of pyruvate kinase isoforms on tumor cells has been extensively studied, but whether PKM2 is required for normal cell proliferation is unknown. We examine how PKM2-deletion affects proliferation and metabolism in non-transformed, non-immortalized PKM2-expressing primary cells. We find that deletion of PKM2 in primary cells results in PKM1 expression and proliferation arrest. PKM1 expression, rather than PKM2 loss, is responsible for this effect, and proliferation arrest cannot be explained by cell differentiation, senescence, death, changes in gene expression, or prevention of cell growth. Instead, PKM1 expression impairs nucleotide production and the ability to synthesize DNA and progress through the cell cycle. Nucleotide biosynthesis is limiting, as proliferation arrest is characterized by severe thymidine depletion, and supplying exogenous thymine rescues both nucleotide levels and cell proliferation. Thus, PKM1 expression promotes a metabolic state that is unable to support DNA synthesis. PMID:25482511

  17. Are in vitro estimates of cell diffusivity and cell proliferation rate sensitive to assay geometry?

    PubMed

    Treloar, Katrina K; Simpson, Matthew J; McElwain, D L Sean; Baker, Ruth E

    2014-09-07

    Cells respond to various biochemical and physical cues during wound-healing and tumour progression. in vitro assays used to study these processes are typically conducted in one particular geometry and it is unclear how the assay geometry affects the capacity of cell populations to spread, or whether the relevant mechanisms, such as cell motility and cell proliferation, are somehow sensitive to the geometry of the assay. In this work we use a circular barrier assay to characterise the spreading of cell populations in two different geometries. Assay 1 describes a tumour-like geometry where a cell population spreads outwards into an open space. Assay 2 describes a wound-like geometry where a cell population spreads inwards to close a void. We use a combination of discrete and continuum mathematical models and automated image processing methods to obtain independent estimates of the effective cell diffusivity, D, and the effective cell proliferation rate, λ. Using our parameterised mathematical model we confirm that our estimates of D and λ accurately predict the time-evolution of the location of the leading edge and the cell density profiles for both assay 1 and assay 2. Our work suggests that the effective cell diffusivity is up to 50% lower for assay 2 compared to assay 1, whereas the effective cell proliferation rate is up to 30% lower for assay 2 compared to assay 1.

  18. Methylprednisolone inhibits the proliferation and affects the differentiation of rat spinal cord-derived neural progenitor cells cultured in low oxygen conditions by inhibiting HIF-1α and Hes1 in vitro.

    PubMed

    Wang, Wenhao; Wang, Peng; Li, Shiyuan; Yang, Jiewen; Liang, Xinjun; Tang, Yong; Li, Yuxi; Yang, Rui; Wu, Yanfeng; Shen, Huiyong

    2014-09-01

    Although there is much controversy over the use of methylprednisolone (MP), it is one of the main drugs used in the treatment of acute spinal cord injury (SCI). The induction of the proliferation and differentiation of endogenous neural progenitor cells (NPCs) is considered a promising mode of treatment for SCI. However, the effects of MP on spinal cord-derived endogenous NPCs in a low oxygen enviroment remain to be delineated. Thus, the aim of this study was to investigate the potential effects of MP on NPCs cultured under low oxygen conditions in vitro and to elucidate the molecular mechanisms involved. Fetal rat spinal cord-derived NPCs were harvested and divided into 4 groups: 2 groups of cells cultured under normal oxygen conditions and treated with or without MP, and 2 groups incubated in 3% O2 (low oxygen) treated in a similar manner. We found that MP induced suppressive effects on NPC proliferation even under low oxygen conditions (3% O2). The proportion of nestin-positive NPCs decreased from 51.8±2.46% to 36.17±3.55% following the addition of MP and decreased more significantly to 27.20±2.68% in the cells cultured in 3% O2. In addition, a smaller number of glial fibrillary acidic protein (GFAP)-positive cells and a greater number of microtubule-associated protein 2 (MAP2)-positive cells was observed following the addition of MP under both normal (normoxic) and low oxygen (hypoxic) conditions. In response to MP treatment, hypoxia-inducible factor-1α (HIF-1α) and the Notch signaling pathway downstream protein, Hes1, but not the upstream Notch-1 intracelluar domain (NICD), were inhibited. After blocking NICD with a γ-secretase inhibitor (DAPT) MP still inhibited the expression of Hes1. Our results provide insight into the molecular mechanisms responsible for the MP-induced inhibition of proliferation and its effects on differentiation and suggest that HIF-1α and Hes1 play an important role in this effect.

  19. Regulation of global gene expression and cell proliferation by APP

    PubMed Central

    Wu, Yili; Zhang, Si; Xu, Qin; Zou, Haiyan; Zhou, Weihui; Cai, Fang; Li, Tingyu; Song, Weihong

    2016-01-01

    Down syndrome (DS), caused by trisomy of chromosome 21, is one of the most common genetic disorders. Patients with DS display growth retardation and inevitably develop characteristic Alzheimer’s disease (AD) neuropathology, including neurofibrillary tangles and neuritic plaques. The expression of amyloid precursor protein (APP) is increased in both DS and AD patients. To reveal the function of APP and elucidate the pathogenic role of increased APP expression in DS and AD, we performed gene expression profiling using microarray method in human cells overexpressing APP. A set of genes are significantly altered, which are involved in cell cycle, cell proliferation and p53 signaling. We found that overexpression of APP inhibits cell proliferation. Furthermore, we confirmed that the downregulation of two validated genes, PSMA5 and PSMB7, inhibits cell proliferation, suggesting that the downregulation of PSMA5 and PSMB7 is involved in APP-induced cell proliferation impairment. Taken together, this study suggests that APP regulates global gene expression and increased APP expression inhibits cell proliferation. Our study provides a novel insight that APP overexpression may contribute to the growth impairment in DS patients and promote AD pathogenesis by inhibiting cell proliferation including neural stem cell proliferation and neurogenesis. PMID:26936520

  20. Regulation of global gene expression and cell proliferation by APP.

    PubMed

    Wu, Yili; Zhang, Si; Xu, Qin; Zou, Haiyan; Zhou, Weihui; Cai, Fang; Li, Tingyu; Song, Weihong

    2016-03-03

    Down syndrome (DS), caused by trisomy of chromosome 21, is one of the most common genetic disorders. Patients with DS display growth retardation and inevitably develop characteristic Alzheimer's disease (AD) neuropathology, including neurofibrillary tangles and neuritic plaques. The expression of amyloid precursor protein (APP) is increased in both DS and AD patients. To reveal the function of APP and elucidate the pathogenic role of increased APP expression in DS and AD, we performed gene expression profiling using microarray method in human cells overexpressing APP. A set of genes are significantly altered, which are involved in cell cycle, cell proliferation and p53 signaling. We found that overexpression of APP inhibits cell proliferation. Furthermore, we confirmed that the downregulation of two validated genes, PSMA5 and PSMB7, inhibits cell proliferation, suggesting that the downregulation of PSMA5 and PSMB7 is involved in APP-induced cell proliferation impairment. Taken together, this study suggests that APP regulates global gene expression and increased APP expression inhibits cell proliferation. Our study provides a novel insight that APP overexpression may contribute to the growth impairment in DS patients and promote AD pathogenesis by inhibiting cell proliferation including neural stem cell proliferation and neurogenesis.

  1. Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation.

    PubMed

    García-Martínez, Olga; De Luna-Bertos, Elvira; Ramos-Torrecillas, Javier; Ruiz, Concepción; Milia, Egle; Lorenzo, María Luisa; Jimenez, Brigida; Sánchez-Ortiz, Araceli; Rivas, Ana

    2016-01-01

    In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11-16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18-22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9-13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly.

  2. Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation

    PubMed Central

    García-Martínez, Olga; De Luna-Bertos, Elvira; Ramos-Torrecillas, Javier; Ruiz, Concepción; Milia, Egle; Lorenzo, María Luisa; Jimenez, Brigida; Sánchez-Ortiz, Araceli; Rivas, Ana

    2016-01-01

    In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11–16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18–22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9–13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly. PMID:26930190

  3. Topography induces differential sensitivity on cancer cell proliferation via Rho-ROCK-Myosin contractility

    PubMed Central

    Chaudhuri, Parthiv Kant; Pan, Catherine Qiurong; Low, Boon Chuan; Lim, Chwee Teck

    2016-01-01

    Although the role of stiffness on proliferative response of cancer cells has been well studied, little is known about the effect of topographic cues in guiding cancer cell proliferation. Here, we examined the effect of topographic cues on cancer cell proliferation using micron scale topographic features and observed that anisotropic features like microgratings at specific dimension could reduce proliferation of non-cancer breast epithelial cells (MCF-10A) but not that for malignant breast cancer cells (MDA-MB-231 and MCF-7). However, isotropic features such as micropillars did not affect proliferation of MCF-10A, indicating that the anisotropic environmental cues are essential for this process. Interestingly, acto-myosin contraction inhibitory drugs, Y-27632 and blebbistatin prevented micrograting-mediated inhibition on proliferation. Here, we propose the concept of Mechanically-Induced Dormancy (MID) where topographic cues could activate Rho-ROCK-Myosin signaling to suppress non-cancerous cells proliferation whereas malignant cells are resistant to this inhibitory barrier and therefore continue uncontrolled proliferation. PMID:26795068

  4. The Selective Antagonism of P2X7 and P2Y1 Receptors Prevents Synaptic Failure and Affects Cell Proliferation Induced by Oxygen and Glucose Deprivation in Rat Dentate Gyrus

    PubMed Central

    Maraula, Giovanna; Lana, Daniele; Coppi, Elisabetta; Gentile, Francesca; Mello, Tommaso; Melani, Alessia; Galli, Andrea; Giovannini, Maria Grazia; Pedata, Felicita; Pugliese, Anna Maria

    2014-01-01

    Purinergic P2X and P2Y receptors are broadly expressed on both neurons and glial cells in the central nervous system (CNS), including dentate gyrus (DG). The aim of this research was to determine the synaptic and proliferative response of the DG to severe oxygen and glucose deprivation (OGD) in acute rat hippocampal slices and to investigate the contribution of P2X7 and P2Y1 receptor antagonism to recovery of synaptic activity after OGD. Extracellular field excitatory post-synaptic potentials (fEPSPs) in granule cells of the DG were recorded from rat hippocampal slices. Nine-min OGD elicited an irreversible loss of fEPSP and was invariably followed by the appearance of anoxic depolarization (AD). Application of MRS2179 (selective antagonist of P2Y1 receptor) and BBG (selective antagonist of P2X7 receptor), before and during OGD, prevented AD appearance and allowed a significant recovery of neurotransmission after 9-min OGD. The effects of 9-min OGD on proliferation and maturation of cells localized in the subgranular zone (SGZ) of slices prepared from rats treated with 5-Bromo-2′-deoxyuridine (BrdU) were investigated. Slices were further incubated with an immature neuron marker, doublecortin (DCX). The number of BrdU+ cells in the SGZ was significantly decreased 6 hours after OGD. This effect was antagonized by BBG, but not by MRS2179. Twenty-four hours after 9-min OGD, the number of BrdU+ cells returned to control values and a significant increase of DCX immunofluorescence was observed. This phenomenon was still evident when BBG, but not MRS2179, was applied during OGD. Furthermore, the P2Y1 antagonist reduced the number of BrdU+ cells at this time. The data demonstrate that P2X7 and P2Y1 activation contributes to early damage induced by OGD in the DG. At later stages after the insult, P2Y1 receptors might play an additional and different role in promoting cell proliferation and maturation in the DG. PMID:25526634

  5. A Neural Network Based Workstation for Automated Cell Proliferation Analysis

    DTIC Science & Technology

    2001-10-25

    proliferation analysis, of cytological microscope images. The software of the system assists the expert biotechnologist during cell proliferation and...work was supported by the Programa de Apoyo a Proyectos de Desarrollo e Investigacíon en Informática REDII 2000. We thank Blanca Itzel Taboada for

  6. PPARα regulates tumor cell proliferation and senescence via a novel target gene carnitine palmitoyltransferase 1C.

    PubMed

    Chen, Yixin; Wang, Yongtao; Huang, Yaoyao; Zeng, Hang; Hu, Bingfang; Guan, Lihuan; Zhang, Huizhen; Yu, Ai-Ming; Johnson, Caroline H; Gonzalez, Frank J; Huang, Min; Bi, Huichang

    2017-03-03

    Carnitine palmitoyltransferase 1C (CPT1C), an enzyme located in the outer mitochondria membrane, has a crucial role in fatty acid transport and oxidation. It is also involved in cell proliferation and is a potential driver for cancer cell senescence. However, its upstream regulatory mechanism is unknown. Peroxisome proliferator activated receptor α (PPARα) is a ligand-activated transcription factor that regulates lipid metabolism and tumor progression. The current study aimed to elucidate whether and how PPARα regulates CPT1C and then affects cancer cell proliferation and senescence. Here, for the first time we report that PPARα directly activated CPT1C transcription and CPT1C was a novel target gene of PPARα, as revealed by dual-luciferase reporter and ChIP assays. Moreover, regulation of CPT1C by PPARα was p53-independent. We further confirmed that depletion of PPARα resulted in low CPT1C expression and then inhibited proliferation and induced senescence of MDA-MB-231 and PANC-1 tumor cell lines in a CPT1C dependent manner, while forced PPARα overexpression promoted cell proliferation and reversed cellular senescence. Taken together, these results indicate that CPT1C is a novel PPARα target gene that regulates cancer cell proliferation and senescence. The PPARα-CPT1C axis may be a new target for the intervention of cancer cellular proliferation and senescence.

  7. Adipose-derived stromal cells inhibit prostate cancer cell proliferation inducing apoptosis

    SciTech Connect

    Takahara, Kiyoshi; Ii, Masaaki; Inamoto, Teruo; Komura, Kazumasa; Ibuki, Naokazu; Minami, Koichiro; Uehara, Hirofumi; Hirano, Hajime; Nomi, Hayahito; Kiyama, Satoshi; Asahi, Michio; Azuma, Haruhito

    2014-04-18

    Highlights: • AdSC transplantation exhibits inhibitory effect on tumor progressions of PCa cells. • AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway. • High expression of the TGF-β1 gene in AdSCs. - Abstract: Mesenchymal stem cells (MSCs) have generated a great deal of interest in the field of regenerative medicine. Adipose-derived stromal cells (AdSCs) are known to exhibit extensive proliferation potential and can undergo multilineage differentiation, sharing similar characteristics to bone marrow-derived MSCs. However, as the effect of AdSCs on tumor growth has not been studied sufficiently, we assessed the degree to which AdSCs affect the proliferation of prostate cancer (PCa) cell. Human AdSCs exerted an inhibitory effect on the proliferation of androgen-responsive (LNCaP) and androgen-nonresponsive (PC3) human PCa cells, while normal human dermal fibroblasts (NHDFs) did not, and in fact promoted PCa cell proliferation to a degree. Moreover, AdSCs induced apoptosis of LNCaP cells and PC3 cells, activating the caspase3/7 signaling pathway. cDNA microarray analysis suggested that AdSC-induced apoptosis in both LNCaP and PC3 cells was related to the TGF-β signaling pathway. Consistent with our in vitro observations, local transplantation of AdSCs delayed the growth of tumors derived from both LNCaP- and PC3-xenografts in immunodeficient mice. This is the first preclinical study to have directly demonstrated that AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway, irrespective of androgen-responsiveness. Since autologous AdSCs can be easily isolated from adipose tissue without any ethical concerns, we suggest that therapy with these cells could be a novel approach for patients with PCa.

  8. Statins Inhibit the Proliferation and Induce Cell Death of Human Papilloma Virus Positive and Negative Cervical Cancer Cells

    PubMed Central

    Crescencio, María Elena; Rodríguez, Emma; Páez, Araceli; Masso, Felipe A.; Montaño, Luis F.; López-Marure, Rebeca

    2009-01-01

    Statins, competitive inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, have anti-tumoral effects on multiple cancer types; however, little is known about their effect on cervical cancer. We evaluated the effect on proliferation, cell cycle, oxidative stress and cell death of three statins on CaSki, HeLa (HPV+) and ViBo (HPV−) cervical cancer cell lines. Cell proliferation was assayed by crystal violet staining, cell cycle by flow cytometry and cell death by annexin-V staining. Reactive oxygen species (ROS) production was evaluated by the oxidation of 2,7-dichlorofluorescein diacetate and nitrite concentration (an indirect measure of nitric oxide (NO) production), by the Griess reaction. Inhibition of cell proliferation by atorvastatin, fluvastatin and simvastatin was dose-dependent. ViBo cells were the most responsive. Statins did not affect the cell cycle, instead they induced cell death. The antiproliferative effect in ViBo cells was completely inhibited with mevalonate, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP) treatments. In contrast, cell proliferation of CaSki and HeLa cells was partially (33%) rescued with these intermediates. The three statins increased ROS and nitrite production, mainly in the ViBo cell line. These results suggest that statins exert anti-tumoral effects on cervical cancer through inhibition of cell proliferation and induction of cell death and oxidative stress. Statins could be an aid in the treatment of cervical cancer, especially in HPV− tumors. PMID:23675166

  9. Nanovesicles engineered from ES cells for enhanced cell proliferation.

    PubMed

    Jeong, Dayeong; Jo, Wonju; Yoon, Jaewoong; Kim, Junho; Gianchandani, Sachi; Gho, Yong Song; Park, Jaesung

    2014-11-01

    Extracellular vesicles (Exosomes and microvesicles) have drawn wide attentions in both diagnostic and therapeutic applications, since they are considered to shuttle biological signals intercellularly. However, further research on exosomes is limited by their rarity and heterogeneity even after lengthy isolation processes. In particular, these limitations are challenging in therapeutic applications. To meet these demands, cell-derived nanovesicles that mimic exosomes were generated by extruding living embryonic stem cells through micro-filters. These nanovesicles have an enclosed lipid bilayer and contain cellular contents. The present study investigated the ability of these nanovesicles to improve proliferation by treating primary murine skin fibroblasts with the nanovesicles. The treated skin fibroblasts showed higher expression levels of mRNA, VEGF-α, protein levels of TGF-β collagen I, PCNA, and Ki-67, as well as enhanced cell proliferation rate and number, compared to non-treated cells. The results indicate that treatment with the nanovesicles could potentially contribute to recovery or wound healing process of tissues.

  10. Cell proliferation and cell death are disturbed during prenatal and postnatal brain development after uranium exposure.

    PubMed

    Legrand, M; Elie, C; Stefani, J; N Florès; Culeux, C; Delissen, O; Ibanez, C; Lestaevel, P; Eriksson, P; Dinocourt, C

    2016-01-01

    The developing brain is more susceptible to neurotoxic compounds than adult brain. It is also well known that disturbances during brain development cause neurological disorders in adulthood. The brain is known to be a target organ of uranium (U) exposure and previous studies have noted that internal U contamination of adult rats induces behavioral disorders as well as affects neurochemistry and neurophysiological properties. In this study, we investigated whether depleted uranium (DU) exposure affects neurogenesis during prenatal and postnatal brain development. We examined the structural morphology of the brain, cell death and finally cell proliferation in animals exposed to DU during gestation and lactation compared to control animals. Our results showed that DU decreases cell death in the cortical neuroepithelium of gestational day (GD) 13 embryos exposed at 40mg/L and 120mg/L and of GD18 fetuses exposed at 120mg/L without modification of the number of apoptotic cells. Cell proliferation analysis showed an increase of BrdU labeling in the dentate neuroepithelium of fetuses from GD18 at 120mg/L. Postnatally, cell death is increased in the dentate gyrus of postnatal day (PND) 0 and PND5 exposed pups at 120mg/L and is associated with an increase of apoptotic cell number only at PND5. Finally, a decrease in dividing cells is observed in the dentate gyrus of PND21 rats developmentally exposed to 120mg/L DU, but not at PND0 and PND5. These results show that DU exposure during brain development causes opposite effects on cell proliferation and cell death processes between prenatal and postnatal development mainly at the highest dose. Although these modifications do not have a major impact in brain morphology, they could affect the next steps of neurogenesis and thus might disrupt the fine organization of the neuronal network.

  11. Rapid evaluation of Antrodia camphorata natural products and derivatives in tumourigenic liver progenitor cells with a novel cell proliferation assay.

    PubMed

    Stewart, Scott G; Ho, Louisa A; Polomska, Marta E; Percival, Alexander T; Yeoh, George C T

    2009-10-01

    We report the syntheses of five natural product maleimide and maleic anhydrides from the mushroom Antrodia camphorata. The ability of these compounds to affect proliferation in non-tumourigenic and tumourigenic liver progenitor cell lines was monitored by the Cellscreen system, a novel and nondestructive rapid-screening instrument. Additionally, a range of new aryl-functionalised differentiated derivatives were prepared through a Suzuki cross-coupling reaction to influence cell-growth effects. Several derivatives radically slowed the proliferation of liver progenitor cells; however, of particular interest were two maleic anhydride derivatives containing aryl tethers. These analogues demonstrated selectivity for limiting the proliferation of tumourigenic progenitor cells in comparison with their non-tumourigenic counterparts. Also highlighted is the application of the Cellscreen system in medicinal chemistry to rapidly measure the effect of compound libraries on cell proliferation.

  12. TGF-beta suppresses EGF-induced MAPK signaling and proliferation in asthmatic epithelial cells.

    PubMed

    Semlali, Abdelhabib; Jacques, Eric; Plante, Sophie; Biardel, Sabrina; Milot, Julie; Laviolette, Michel; Boulet, Louis-Philippe; Chakir, Jamila

    2008-02-01

    Epithelial damage is an important pathophysiologic feature of asthma. Bronchial epithelium damage results in release of growth factors such as transforming growth factor (TGF)-beta(1) that may affect epithelial cell proliferation. The objective of our study is to evaluate the importance of TGF-beta(1) in regulating epithelial cell repair in asthma. We evaluated the effect of TGF-beta(1) on epidermal growth factor (EGF)-induced proliferation and downstream signaling in epithelial cells obtained from subjects with asthma compared with cells from healthy subjects. Cell proliferation was evaluated by bromodeoxyuridine incorporation. EGF receptor (EGFR), mitogen-activated protein kinase, TGF-beta receptors, Smads, Smad anchor for receptor activation (SARA), and cyclin-dependant kinase inhibitors were evaluated by Western blot. TGF-beta(1) and receptor expression were measured by RT-PCR and by enzyme-linked immunosorbent assay. Proliferation of epithelial cells at baseline and after EGF stimulation was significantly reduced in cells derived from subjects with asthma compared with cells obtained from healthy control subjects. EGF-induced ERK1/2 phosphorylation was reduced in epithelial cells from subjects with asthma compared with cells from healthy control subjects. This was paralleled with a reduced EGFR phosphorylation. Addition of TGF-beta(1) significantly decreased EGF-induced cell proliferation. TGF-beta(1) production was higher in asthmatic epithelial cells compared with normal cells. This was supported by a high expression of pSmad 3 and SARA in cells derived from individuals with asthma compared with normal subjects. Cycline-dependent kinase inhibitors were highly expressed in asthmatic compared with normal cells. Inhibition of TGF-beta(1) signaling in asthmatic epithelial cells restored EGFR, ERK1/2 phosphorylation, and cell proliferation induced by EGF. Our results suggest that TGF-beta restrains EGFR phosphorylation and downstream signaling in bronchial

  13. miR-186 affects the proliferation, invasion and migration of human gastric cancer by inhibition of Twist1

    PubMed Central

    Cao, Chunhong; Sun, Deguang; Zhang, Liang; Song, Lei

    2016-01-01

    Recent evidence shows that miRNAs are dysregulated in a variety of cancers including gastric cancer (GC), and emerging as key oncogenes or tumor suppressors. In this study, qRT-PCR was used to analyze the expression of miR-186 in GC tissues and adjacent non-cancerous tissues, and then more in-vitro experiments were used to investigate the role of miR-186 in GC cells. Here, we identified miR-186 was generally down-regulated in GC tissues; however, Twist1 was generally up-regulated in GC tissues. Moreover, miR-186 and Twist1 were associated with larger tumor size and advanced clinical stage of GC. In-vitro experiments demonstrated that ectopic overexpression of miR-186 inhibited GC cell proliferation, invasion and migration; however, inhibited expression of miR-186 enhanced cell proliferation, invasion and migration. Furthermore, the luciferase reporter assay demonstrated Twist1 as a direct target of miR-186. Finally, over-expression of Twist1 abrogated inhibitory impact of miR-186 on cell proliferation, invasion and migration. In conclusion, miR-186 affects the proliferation, invasion and migration of human gastric cancer by inhibition of Twist1, and could be a tumor suppressor in GC development. Thus, miR-186 may be served as a candidate prognostic biomarker and target for new therapies in human gastric cancer. PMID:27835599

  14. Differential migration and proliferation of geometrical ensembles of cell clusters

    SciTech Connect

    Kumar, Girish; Chen, Bo; Co, Carlos C.; Ho, Chia-Chi

    2011-06-10

    Differential cell migration and growth drives the organization of specific tissue forms and plays a critical role in embryonic development, tissue morphogenesis, and tumor invasion. Localized gradients of soluble factors and extracellular matrix have been shown to modulate cell migration and proliferation. Here we show that in addition to these factors, initial tissue geometry can feedback to generate differential proliferation, cell polarity, and migration patterns. We apply layer by layer polyelectrolyte assembly to confine multicellular organization and subsequently release cells to demonstrate the spatial patterns of cell migration and growth. The cell shapes, spreading areas, and cell-cell contacts are influenced strongly by the confining geometry. Cells within geometric ensembles are morphologically polarized. Symmetry breaking was observed for cells on the circular pattern and cells migrate toward the corners and in the direction parallel to the longest dimension of the geometric shapes. This migration pattern is disrupted when actomyosin based tension was inhibited. Cells near the edge or corner of geometric shapes proliferate while cells within do not. Regions of higher rate of cell migration corresponded to regions of concentrated growth. These findings demonstrate that multicellular organization can result in spatial patterns of migration and proliferation.

  15. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    SciTech Connect

    Pawelec, K. M. E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E.; Wardale, R. J. E-mail: jw626@cam.ac.uk

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  16. EDA-Containing Fibronectin Increases Proliferation of Embryonic Stem Cells

    PubMed Central

    Losino, Noelia; Waisman, Ariel; Solari, Claudia; Luzzani, Carlos; Espinosa, Darío Fernández; Sassone, Alina; Muro, Andrés F.; Miriuka, Santiago; Sevlever, Gustavo; Barañao, Lino; Guberman, Alejandra

    2013-01-01

    Embryonic stem cells (ESC) need a set of specific factors to be propagated. They can also grow in conditioned medium (CM) derived from a bovine granulosa cell line BGC (BGC-CM), a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA+). Here, we investigated if the FN EDA+ isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF) lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA-), and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC’s proliferation rate. Here we showed for the first time that this FN isoform enhances ESC’s proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy. PMID:24244705

  17. EDA-containing fibronectin increases proliferation of embryonic stem cells.

    PubMed

    Losino, Noelia; Waisman, Ariel; Solari, Claudia; Luzzani, Carlos; Espinosa, Darío Fernández; Sassone, Alina; Muro, Andrés F; Miriuka, Santiago; Sevlever, Gustavo; Barañao, Lino; Guberman, Alejandra

    2013-01-01

    Embryonic stem cells (ESC) need a set of specific factors to be propagated. They can also grow in conditioned medium (CM) derived from a bovine granulosa cell line BGC (BGC-CM), a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA(+)). Here, we investigated if the FN EDA(+) isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF) lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA(-)), and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC's proliferation rate. Here we showed for the first time that this FN isoform enhances ESC's proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy.

  18. Chromatin Remodeling, Cell Proliferation and Cell Death in Valproic Acid-Treated HeLa Cells

    PubMed Central

    Felisbino, Marina Barreto; Tamashiro, Wirla M. S. C.; Mello, Maria Luiza S.

    2011-01-01

    Background Valproic acid (VPA) is a potent anticonvulsant that inhibits histone deacetylases. Because of this inhibitory action, we investigated whether VPA would affect chromatin supraorganization, mitotic indices and the frequency of chromosome abnormalities and cell death in HeLa cells. Methodology/Principal Findings Image analysis was performed by scanning microspectrophotometry for cells cultivated for 24 h, treated with 0.05, 0.5 or 1.0 mM VPA for 1–24 h, and subjected to the Feulgen reaction. TSA-treated cells were used as a predictable positive control. DNA fragmentation was investigated with the TUNEL assay. Chromatin decondensation was demonstrated under TSA and all VPA treatments, but no changes in chromosome abnormalities, mitotic indices or morphologically identified cell death were found with the VPA treatment conditions mentioned above, although decreased mitotic indices were detected under higher VPA concentration and longer exposure time. The frequency of DNA fragmentation identified with the TUNEL assay in HeLa cells increased after a 24-h VPA treatment, although this fragmentation occurred much earlier after treatment with TSA. Conclusions/Significance The inhibition of histone deacetylases by VPA induces chromatin remodeling in HeLa cells, which suggests an association to altered gene expression. Under VPA doses close to the therapeutic antiepileptic plasma range no changes in cell proliferation or chromosome abnormalities are elicited. The DNA fragmentation results indicate that a longer exposure to VPA or a higher VPA concentration is required for the induction of cell death. PMID:22206001

  19. HB-EGF affects astrocyte morphology, proliferation, differentiation, and the expression of intermediate filament proteins.

    PubMed

    Puschmann, Till B; Zandén, Carl; Lebkuechner, Isabell; Philippot, Camille; de Pablo, Yolanda; Liu, Johan; Pekny, Milos

    2014-03-01

    Heparin-binding epidermal growth factor-like growth factor (HB-EGF), a vascular-derived trophic factor, belongs to the epidermal growth factor (EGF) family of neuroprotective, hypoxia-inducible proteins released by astrocytes in CNS injuries. It was suggested that HB-EGF can replace fetal calf serum (FCS) in astrocyte cultures. We previously demonstrated that in contrast to standard 2D cell culture systems, Bioactive3D culture system, when used with FCS, minimizes the baseline activation of astrocytes and preserves their complex morphology. Here, we show that HB-EGF induced EGF receptor (EGFR) activation by Y1068 phosphorylation, Mapk/Erk pathway activation, and led to an increase in cell proliferation, more prominent in Bioactive3D than in 2D cultures. HB-EGF changed morphology of 2D and Bioactive3D cultured astrocytes toward a radial glia-like phenotype and induced the expression of intermediate filament and progenitor cell marker protein nestin. Glial fibrillary acidic protein (GFAP) and vimentin protein expression was unaffected. RT-qPCR analysis demonstrated that HB-EGF affected the expression of Notch signaling pathway genes, implying a role for the Notch signaling in HB-EGF-mediated astrocyte response. HB-EGF can be used as a FCS replacement for astrocyte expansion and in vitro experimentation both in 2D and Bioactive3D culture systems; however, caution should be exercised since it appears to induce partial de-differentiation of astrocytes.

  20. Role of Calmodulin in Cell Proliferation

    NASA Technical Reports Server (NTRS)

    Chafouleas, J.

    1983-01-01

    Calmodulin levels were found to increase as cells enter plateau. The data suggest that the cells are exiting the cell cycle late in the G sub 1 phase, or that the calmodulin levels in plateau cells are uncoupled to progression into S phase in plateau cells. Upon release, calmodulin levels rapidly decrease. Following this decrease, there is a increase prior to S phase.

  1. Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

    SciTech Connect

    Xu, Yang; Pang, Xiaoyan; Dong, Mei; Wen, Fang Zhang, Yi

    2013-11-01

    Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesity has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients.

  2. Pak2 regulates hematopoietic progenitor cell proliferation, survival and differentiation

    PubMed Central

    Zeng, Yi; Broxmeyer, Hal E.; Staser, Karl; Chitteti, Brahmananda Reddy; Park, Su-Jung; Hahn, Seongmin; Cooper, Scott; Sun, Zejin; Jiang, Li; Yang, XianLin; Yuan, Jin; Kosoff, Rachelle; Sandusky, George; Srour, Edward F.; Chernoff, Jonathan; Clapp, Wade

    2015-01-01

    p21-activated kinase 2 (Pak2), a serine/threonine kinase, has been previously shown to be essential for hematopoietic stem cell (HSC) engraftment. However, Pak2 modulation of long-term hematopoiesis and lineage commitment remain unreported. Utilizing a conditional Pak2 knock out (KO) mouse model, we found that disruption of Pak2 in HSCs induced profound leukopenia and a mild macrocytic anemia. Although loss of Pak2 in HSCs leads to less efficient short- and long-term competitive hematopoiesis than wild type (WT) cells, it does not affect HSC self-renewal per se. Pak2 disruption decreased the survival and proliferation of multi-cytokine stimulated immature progenitors. Loss of Pak2 skewed lineage differentiation toward granulocytopoiesis and monocytopoiesis in mice as evidenced by 1) a three to six-fold increase in the percentage of peripheral blood granulocytes and a significant increase in the percentage of granulocyte-monocyte progenitors (GMPs) in mice transplanted with Pak2-disrupted BM; 2) Pak2-disrupted BM and c-kit+ cells yielded higher numbers of more mature subsets of granulocyte-monocyte colonies and polymophonuclear neutrophils (PMNs), respectively, when cultured in the presence of granulocyte-macrophage colony stimulating factor (GM-CSF). Pak2 disruption resulted respectively in decreased and increased gene expression of transcription factors JunB and c-Myc, which may suggest underlying mechanisms by which Pak2 regulates granulocyte-monocyte lineage commitment. Furthermore, Pak2 disruption led to 1) higher percentage of CD4+CD8+ double positive T cells and lower percentages of CD4+CD8− or CD4−CD8+ single positive T cells in thymus and 2) decreased numbers of mature B cells and increased numbers of Pre-Pro B cells in BM, suggesting defects in lymphopoiesis. PMID:25586960

  3. Cell cycles and proliferation patterns in Haematococcus pluvialis

    NASA Astrophysics Data System (ADS)

    Zhang, Chunhui; Liu, Jianguo; Zhang, Litao

    2016-09-01

    Most studies on Haematococcus pluvialis have been focused on cell growth and astaxanthin accumulation; far less attention has been paid to cell cycles and proliferation patterns. The purpose of this study was to clarify cell cycles and proliferation patterns in H. pluvialis microscopically using a camera and video recorder system. The complicated life history of H. pluvialis can be divided into two stages: the motile stage and the non-motile stage. All the cells can be classified into forms as follows: motile cell, non-motile cell, zoospore and aplanospore. The main cell proliferation, both in the motile phase and non-motile phase in H. pluvialis, is by asexual reproduction. Under normal growth conditions, a motile cell usually produces two, sometimes four, and exceptionally eight zoospores. Under unfavorable conditions, the motile cell loses its flagella and transforms into a non-motile cell, and the non-motile cell usually produces 2, 4 or 8 aplanospores, and occasionally 20-32 aplanospores, which further develop into non-motile cells. Under suitable conditions, the non-motile cell is also able to release zoospores. The larger non-motile cells produce more than 16 zoospores, and the smaller ones produce 4 or 8 zoospores. Vegetative reproduction is by direct cell division in the motile phase and by occasional cell budding in the non-motile phase. There is, as yet, no convincing direct evidence for sexual reproduction.

  4. Ethylene Inhibits Cell Proliferation of the Arabidopsis Root Meristem.

    PubMed

    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.

  5. Ectopic expression of syndecan-1 in basal epidermis affects keratinocyte proliferation and wound re-epithelialization.

    PubMed

    Ojeh, Nkemcho; Hiilesvuo, Katri; Wärri, Anni; Salmivirta, Markku; Henttinen, Tiina; Määttä, Arto

    2008-01-01

    Epidermal proliferation and differentiation can be regulated by soluble morphogens and growth factors. Heparan sulfate proteoglycans (HSPGs) modulate the action of several of these effector molecules, such as members of the fibroblast growth factor (FGF) and Wnt families. Syndecan-1 is a cell-surface proteoglycan that is expressed in differentiating keratinocytes and transiently upregulated in all layers of the epidermis upon tissue injury. To address the role of syndecan-1 in the regulation of keratinocyte proliferation and differentiation, we generated transgenic mice that overexpress syndecan-1 under K14 keratin promoter in the basal layer of the epidermis. We observed epidermal hyperproliferation in newborn transgenic mice, as evidenced by increased number of suprabasal cell layers, elevated proliferating cell nuclear antigen (PCNA) expression in both basal and suprabasal cell layers and by expression of keratin 6 in the interfollicular epidermis. Compared to both wild-type and syndecan-1-null animals, the transgene expression interfered with skin wound healing in adult mice by decreasing cell proliferation in the re-epithelialized epidermis. Thus, syndecan-1 regulates keratinocyte proliferation differently during skin development and in healing wounds.

  6. Low doses of TiO2-polyethylene glycol nanoparticles stimulate proliferation of hepatocyte cells.

    PubMed

    Sun, Qingqing; Kanehira, Koki; Taniguchi, Akiyoshi

    2016-01-01

    This paper describes the effect of low concentrations of 100 nm polyethylene glycol-modified TiO2 nanoparticles (TiO2-PEG NPs) on HepG2 hepatocellular carcinoma cells. Proliferation of HepG2 cells increased significantly when the cells were exposed to low doses (<100 μg ml(-1)) of TiO2-PEG NPs. These results were further confirmed by cell counting experiments and cell cycle assays. Cellular uptake assays were performed to determine why HepG2 cells proliferate with low-dose exposure to TiO2-PEG NPs. The results showed that exposure to lower doses of NPs led to less cellular uptake, which in turn decreased cytotoxicity. We therefore hypothesized that TiO2-PEG NPs could affect the activity of hepatocyte growth factor receptors (HGFRs), which bind to hepatocyte growth factor and stimulate cell proliferation. The localization of HGFRs on the surface of the cell membrane was detected via immunofluorescence staining and confocal microscopy. The results showed that HGFRs aggregate after exposure to TiO2-PEG NPs. In conclusion, our results indicate that TiO2-PEG NPs have the potential to promote proliferation of HepG2 cells through HGFR aggregation and suggest that NPs not only exhibit cytotoxicity but also affect cellular responses.

  7. Low doses of TiO2-polyethylene glycol nanoparticles stimulate proliferation of hepatocyte cells

    PubMed Central

    Sun, Qingqing; Kanehira, Koki; Taniguchi, Akiyoshi

    2016-01-01

    Abstract This paper describes the effect of low concentrations of 100 nm polyethylene glycol-modified TiO2 nanoparticles (TiO2-PEG NPs) on HepG2 hepatocellular carcinoma cells. Proliferation of HepG2 cells increased significantly when the cells were exposed to low doses (<100 μg ml–1) of TiO2-PEG NPs. These results were further confirmed by cell counting experiments and cell cycle assays. Cellular uptake assays were performed to determine why HepG2 cells proliferate with low-dose exposure to TiO2-PEG NPs. The results showed that exposure to lower doses of NPs led to less cellular uptake, which in turn decreased cytotoxicity. We therefore hypothesized that TiO2-PEG NPs could affect the activity of hepatocyte growth factor receptors (HGFRs), which bind to hepatocyte growth factor and stimulate cell proliferation. The localization of HGFRs on the surface of the cell membrane was detected via immunofluorescence staining and confocal microscopy. The results showed that HGFRs aggregate after exposure to TiO2-PEG NPs. In conclusion, our results indicate that TiO2-PEG NPs have the potential to promote proliferation of HepG2 cells through HGFR aggregation and suggest that NPs not only exhibit cytotoxicity but also affect cellular responses. PMID:27877913

  8. Inflammation and Proliferation Act Together to Mediate Intestinal Cell Fusion

    PubMed Central

    Swain, John R.; Wong, Melissa H.

    2009-01-01

    Cell fusion between circulating bone marrow-derived cells (BMDCs) and non-hematopoietic cells is well documented in various tissues and has recently been suggested to occur in response to injury. Here we illustrate that inflammation within the intestine enhanced the level of BMDC fusion with intestinal progenitors. To identify important microenvironmental factors mediating intestinal epithelial cell fusion, we performed bone marrow transplantation into mouse models of inflammation and stimulated epithelial proliferation. Interestingly, in a non-injury model or in instances where inflammation was suppressed, an appreciable baseline level of fusion persisted. This suggests that additional mediators of cell fusion exist. A rigorous temporal analysis of early post-transplantation cellular dynamics revealed that GFP-expressing donor cells first trafficked to the intestine coincident with a striking increase in epithelial proliferation, advocating for a required fusogenic state of the host partner. Directly supporting this hypothesis, induction of augmented epithelial proliferation resulted in a significant increase in intestinal cell fusion. Here we report that intestinal inflammation and epithelial proliferation act together to promote cell fusion. While the physiologic impact of cell fusion is not yet known, the increased incidence in an inflammatory and proliferative microenvironment suggests a potential role for cell fusion in mediating the progression of intestinal inflammatory diseases and cancer. PMID:19657387

  9. Cholesterol induces proliferation of chicken primordial germ cells.

    PubMed

    Chen, Dongyang; Chen, Meijuan; Lu, Zhenping; Yang, Mengmeng; Xie, Long; Zhang, Wenxin; Xu, Huiyan; Lu, Kehuan; Lu, Yangqing

    2016-08-01

    Primordial germ cells (PGCs) are the precursors of sperm and eggs and may serve as suitable cells for use in research in developmental biology and transgenic animals. However, the long-term propagation of PGCs in vitro has so far been plagued by the loss of their germ cell characteristics. This is largely because of the scarcity of knowledge concerning cell division and proliferation in these cells and the poor optimization of the culture medium. The sonic hedgehog (SHH) signaling pathway is involved in proliferation of many types of cells, but little is known about its role in chicken PGCs. The results of the current study indicate that the proliferation of chicken PGCs increases significantly when cholesterol, a molecule that facilitates the trafficking of HH ligands, is supplemented in the culture medium. This effect was attenuated when an SHH antagonist, cyclopamine was added, suggesting the involvement of SHH signaling in this process. The characterization of PGCs treated with cholesterol has shown that these cells express germ-cell-related markers and retain their capability to colonize the embryonic gonad after re-introduction to vasculature of stage-15 HH embryos, indicating that proliferation of PGCs induced by cholesterol does not alter the germ cell characteristics of these cells.

  10. Effects of Hedera helix L. extracts on rat prostate cancer cell proliferation and motility

    PubMed Central

    Gumushan-Aktas, Hatice; Altun, Seyhan

    2016-01-01

    Hedera helix L., a member of Araliaceae family, has antiproliferative, cytotoxic, antimicrobial, antifungal, antiprotozoal and anti-inflammatory effects, and is used in cosmetics. The aim of the present study was to investigate the effect of treatment with extracts of leaves and unripened fruits of H. helix on rat prostate cancer cell lines with markedly different metastatic potentials: Mat-LyLu cells (strongly metastatic) and AT-2 cells (weakly metastatic). The effects of the extracts on cell kinetics and migration were determined. Tetrodotoxin was used to block the voltage-gated sodium channels (VGSCs) associated specifically with Mat-LyLu cells. Cell proliferation was detected spectrophotometrically using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. The mitotic index was determined using the Feulgen staining method. Lateral motility was quantified by wound-healing assays. The results of the present study demonstrated that cell kinetics (proliferation and mitotic activity) and motility were inhibited by ethanolic leaf extract of H. helix. The ethanolic extract of H. helix fruit suppressed Mat-LyLu cell migration, with no effect on proliferation. The opposite effects were observed in AT-2 cells; migration was not affected but proliferation was inhibited. In conclusion, the ethanolic fruit extract of H. helix may inhibit the cell migration of Mat-LyLu cells by blocking VGSCs. However, the effect of ethanolic leaf extract of H. helix treatment on the lateral motility of the cancer cells is unclear. PMID:27698887

  11. Ghrelin promotes oral tumor cell proliferation by modifying GLUT1 expression.

    PubMed

    Kraus, Dominik; Reckenbeil, Jan; Wenghoefer, Matthias; Stark, Helmut; Frentzen, Matthias; Allam, Jean-Pierre; Novak, Natalija; Frede, Stilla; Götz, Werner; Probstmeier, Rainer; Meyer, Rainer; Winter, Jochen

    2016-03-01

    In our study, ghrelin was investigated with respect to its capacity on proliferative effects and molecular correlations on oral tumor cells. The presence of all molecular components of the ghrelin system, i.e., ghrelin and its receptors, was analyzed and could be detected using real-time PCR and immunohistochemistry. To examine cellular effects caused by ghrelin and to clarify downstream-regulatory mechanisms, two different oral tumor cell lines (BHY and HN) were used in cell culture experiments. Stimulation of either cell line with ghrelin led to a significantly increased proliferation. Signal transduction occurred through phosphorylation of GSK-3β and nuclear translocation of β-catenin. This effect could be inhibited by blocking protein kinase A. Glucose transporter1 (GLUT1), as an important factor for delivering sufficient amounts of glucose to tumor cells having high requirements for this carbohydrate (Warburg effect) was up-regulated by exogenous and endogenous ghrelin. Silencing intracellular ghrelin concentrations using siRNA led to a significant decreased expression of GLUT1 and proliferation. In conclusion, our study describes the role for the appetite-stimulating peptide hormone ghrelin in oral cancer proliferation under the particular aspect of glucose uptake: (1) tumor cells are a source of ghrelin. (2) Ghrelin affects tumor cell proliferation through autocrine and/or paracrine activity. (3) Ghrelin modulates GLUT1 expression and thus indirectly enhances tumor cell proliferation. These findings are of major relevance, because glucose uptake is assumed to be a promising target for cancer treatment.

  12. Statins inhibited erythropoietin-induced proliferation of rat vascular smooth muscle cells.

    PubMed

    Kaneda, Tae; Tsuruoka, Shuichi; Fujimura, Akio

    2010-12-15

    Erythropoietin (EPO) directly stimulates the proliferation of vascular smooth muscle cells, and this is believed to be one of the mechanisms of vascular access failure of hemodialysis patients. However, precise mechanisms of the EPO-induced proliferation of vascular smooth muscle cells are not certain. HMG-CoA reductase inhibitors (statins) are primarily used to reduce cholesterol levels, but also exert other effects, including reno-protective effects. We evaluated the effect of several statins with various hydrophilicities on the EPO-induced proliferation of primary cultured rat vascular smooth muscle cells (VSMCs) in vitro. EPO significantly and concentration-dependently increased DNA synthesis as assessed by [³H]thymidine incorporation, cell proliferation as assessed by WST-1 assay, and activation of the p44/42MAPK pathway. Therapeutic doses of statins (pravastatin, simvastatin, atorvastatin and fluvastatin) in patients with hypercholesterolemia almost completely suppressed all of the EPO-induced effects in a concentration-dependent manner. Co-addition of mevalonic acid almost completely reversed the effects of statins. Statin alone did not affect the basal proliferation capacity of the cells. The effects were almost similar among the statins. We concluded that statins inhibited EPO-induced proliferation in rat VSMCs at least partly through their inhibition of HMG-CoA reductase activity. In the future, statins might prove useful for the treatment of EPO-induced hyperplasia of vascular access. Because the statins all showed comparable effects irrespective of their hydrophilicities, these effects might be a class effect.

  13. Maternal enrichment affects prenatal hippocampal proliferation and open-field behaviors in female offspring mice.

    PubMed

    Maruoka, Takashi; Kodomari, Ikuko; Yamauchi, Rena; Wada, Etsuko; Wada, Keiji

    2009-04-17

    The maternal environment is thought to be important for fetal brain development. However, the effects of maternal environment are not fully understood. Here, we investigated whether enrichment of the maternal environment can influence prenatal brain development and postnatal behaviors in mice. An enriched environment is a housing condition with several objects such as a running wheel, tube and ladder, which are thought to increase sensory, cognitive and motor stimulation in rodents compared with standard housing conditions. First, we measured the number of BrdU-positive cells in the hippocampal dentate gyrus of fetuses from pregnant dams housed in an enriched environment. Our results revealed that maternal enrichment influences cell proliferation in the hippocampus of female, but not male, fetuses. Second, we used the open-field test to investigate postnatal behaviors in the offspring of dams housed in the enriched environment during pregnancy. We found that maternal enrichment significantly affects the locomotor activity and time spent in the center of the open-field in female, but not male, offspring. These results indicate that maternal enrichment influences prenatal brain development and postnatal behaviors in female offspring.

  14. Downregulation of FOXP1 Inhibits Cell Proliferation in Hepatocellular Carcinoma by Inducing G1/S Phase Cell Cycle Arrest

    PubMed Central

    Wang, Xin; Sun, Ji; Cui, Meiling; Zhao, Fangyu; Ge, Chao; Chen, Taoyang; Yao, Ming; Li, Jinjun

    2016-01-01

    Forkhead box P1 (FOXP1) belongs to a family of winged-helix transcription factors that are involved in the processes of cellular proliferation, differentiation, metabolism, and longevity. FOXP1 can affect cell proliferation and migratory ability in hepatocellular carcinoma (HCC) in vitro. However, little is known about the mechanism of FOXP1 in the proliferation of HCC cells. This study aimed to further explore the function of FOXP1 on the proliferation of HCC cells as well as the relevant mechanism involved. Western blot analysis, tumor xenograft models, and flow cytometry analysis were performed to elucidate the function of FOXP1 in the regulation of cell proliferation in human HCC. We observed that silencing FOXP1 significantly suppressed the growth ability of HCC cells both in vitro and in vivo. In addition, knockdown of FOXP1 induced G1/S phase arrest, and the expression of total and phosphorylated Rb (active type) as well as the levels of E2F1 were markedly decreased at 24 h; however, other proteins, including cyclin-dependent kinase (CDK) 4 and 6 and cyclin D1 did not show noticeable changes. In conclusion, downregulation of FOXP1 inhibits cell proliferation in hepatocellular carcinoma by inducing G1/S phase cell cycle arrest, and the decrease in phosphorylated Rb is the main contributor to this G1/S phase arrest. PMID:27618020

  15. S100P is a potential molecular target of cadmium-induced inhibition of human placental trophoblast cell proliferation.

    PubMed

    Zhou, Taimei; Wang, Haiying; Zhang, Shen; Jiang, Xinglin; Wei, Xiaolong

    2016-11-01

    Cadmium, a common and highly toxic pollutant, has been known to accumulate high concentrations in placenta with deleterious effects on placental structure and function. Cadmium inhibits cell proliferation in placenta via targeting metal binding proteins. S100P, a Ca(2+)-binding protein, plays an important role in promoting cell proliferation and our previous study found its downregulation was linked to cadmium exposure in Guiyu, a famous e-waste recycling town in China. So, the present study was aimed to define whether cadmium inhibited cell proliferation through interfering with S100P. Using human trophoblast-derived HTR-8/SVneo cells as a model in vitro, we showed that cadmium exposure led to decreases in both cell proliferation and S100P expression. Knockdown of S100P in HTR-8/SVneo cells led to an obvious decrease of cell proliferation, and upregulation of S100P resulted in a significant increase of cell proliferation. Furthermore, after 24h of exposure to cadmium (20μM), cells transfected with pcDNA3.1-S100P showed a 1.3-fold higher S100P protein level, 38% higher proliferation evaluated with MTT assay than cells with no transfection, indicating that S100P expression attenuated cadmium-induced inhibition of cell proliferation. Taken together, we demonstrate that cadmium inhibits S100P expression and cell proliferation in placenta, meanwhile, S100P expression affects cell proliferation. Thus, our study is the first to indicate that cadmium may induce inhibition of placental trophoblast cell proliferation through targeting S100P.

  16. Stretched cell cycle model for proliferating lymphocytes

    PubMed Central

    Dowling, Mark R.; Kan, Andrey; Heinzel, Susanne; Zhou, Jie H. S.; Marchingo, Julia M.; Wellard, Cameron J.; Markham, John F.; Hodgkin, Philip D.

    2014-01-01

    Stochastic variation in cell cycle time is a consistent feature of otherwise similar cells within a growing population. Classic studies concluded that the bulk of the variation occurs in the G1 phase, and many mathematical models assume a constant time for traversing the S/G2/M phases. By direct observation of transgenic fluorescent fusion proteins that report the onset of S phase, we establish that dividing B and T lymphocytes spend a near-fixed proportion of total division time in S/G2/M phases, and this proportion is correlated between sibling cells. This result is inconsistent with models that assume independent times for consecutive phases. Instead, we propose a stretching model for dividing lymphocytes where all parts of the cell cycle are proportional to total division time. Data fitting based on a stretched cell cycle model can significantly improve estimates of cell cycle parameters drawn from DNA labeling data used to monitor immune cell dynamics. PMID:24733943

  17. Mechanism of inhibition of cell proliferation by Vinca alkaloids.

    PubMed

    Jordan, M A; Thrower, D; Wilson, L

    1991-04-15

    We have used a structure-activity approach to investigate whether the Vinca alkaloids inhibit cell proliferation primarily by means of their effects on mitotic spindle microtubules or by another mechanism or by a combination of mechanisms. Five Vinca alkaloids were used to investigate the relationship in HeLa cells between inhibition of cell proliferation and blockage of mitosis, alteration of spindle organization, and depolymerization of microtubules. Indirect immunofluorescence staining of microtubules and 4,6-diamidino-2-phenylindole staining of chromatin were used to characterize the effects of the drugs on the distributions of cells in stages of the cell cycle and on the organization of microtubules and chromosomes in metaphase spindles. The microtubule polymer was isolated from cells and quantified using a competitive enzyme-linked immunoadsorbent assay for tubulin. We observed a nearly perfect coincidence between the concentration of each Vinca derivative that inhibited cell proliferation and the concentration that caused 50% accumulation of cells at metaphase, despite the fact that the antiproliferative potencies of the drugs varied over a broad concentration range. Inhibition of cell proliferation and blockage of cells at metaphase at the lowest effective concentrations of all Vinca derivatives occurred with little or no microtubule depolymerization or spindle disorganization. With increasing drug concentrations, the organization of microtubules and chromosomes in arrested mitotic spindles deteriorated in a manner that was common to all five congeners. These results indicate that the antiproliferative activity of the Vinca alkaloids at their lowest effective concentrations in HeLa cells is due to inhibition of mitotic spindle function. The results suggest further that the Vinca alkaloids inhibit cell proliferation by altering the dynamics of tubulin addition and loss at the ends of mitotic spindle microtubules rather than by depolymerizing the microtubules

  18. LaAP2L1, a heterosis-associated AP2/EREBP transcription factor of Larix, increases organ size and final biomass by affecting cell proliferation in Arabidopsis.

    PubMed

    Li, Ai; Zhou, Yanan; Jin, Chuan; Song, Wenqin; Chen, Chengbin; Wang, Chunguo

    2013-11-01

    In Larix and in some crops, heterosis is prevalent and has been widely used in breeding to produce excellent varieties. However, the molecular basis of heterosis in Larix remains ambiguous. LaAP2L1, a member of the AP2/EREBP transcription factor family, has been suggested to be involved in heterosis in Larix hybrids. Here, the function and regulation of LaAP2L1 were further explored. Overexpression of LaAP2L1 led to markedly enlarged organs and heterosis-like traits in Arabidopsis. Fresh weight of leaves was almost twice as great as in vector controls. Likewise, seed yield of 35S::LaAP2L1 individual plants was >200% greater than that of control plants. The enlarged organs and heterosis-like traits displayed by 35S::LaAP2L1 plants were mainly due to enhanced cell proliferation and prolonged growth duration. At the molecular level, LaAP2L1 upregulated the expression of ANT, EBP1, and CycD3;1 and inhibited the expression of ARGOS in 35S::LaAP2L1 plants, suggesting an important molecular role of LaAP2L1 in regulating plant organ development. These findings provide new insights into the formation of heterosis in woody plants and suggest that LaAP2L1 has potential applications in breeding high-yielding crops and energy plants. In addition, 50 AP2/EREBP transcription factors, including LaAP2L1, in Larix were identified by transcriptome sequencing, and phylogenetic analysis was conducted. This provided information that will be important in further revealing the functions of these transcription factors.

  19. Effects of androgen receptor polyglutamine tract expansion on proliferation of NG108-15 cells.

    PubMed

    Nakajima, H; Kimura, F; Nakagawa, T; Ikemoto, T; Furutama, D; Shinoda, K; Kato, S; Shimizu, A; Ohsawa, N

    1997-01-31

    Expansion of the polyglutamine tracts in the androgen receptor (AR) has been recognized as a cause of X-linked spinal and bulbar muscular atrophy (SBMA). In the present study, NG108-15 cells were stably transfected with expression vectors coding for either the wild type (WT) AR gene (CAG repeat number = 22) or a mutated (MT) AR gene (CAG repeat number = 52). Cells proliferation and cell cycle parameters were evaluated for NG108-15-WT and NG108-15-MT cells in the presence or absence of androgen. NG108-15-WT cells demonstrated an androgen-dependent increase in cell number, while NG108-15-MT cells did not. Our results demonstrate that expansion of polyglutamine tracts in the AR may affect the proliferation and differentiation of nerve cells.

  20. Logistic Proliferation of Cells in Scratch Assays is Delayed.

    PubMed

    Jin, Wang; Shah, Esha T; Penington, Catherine J; McCue, Scott W; Maini, Philip K; Simpson, Matthew J

    2017-03-23

    Scratch assays are used to study how a population of cells re-colonises a vacant region on a two-dimensional substrate after a cell monolayer is scratched. These experiments are used in many applications including drug design for the treatment of cancer and chronic wounds. To provide insights into the mechanisms that drive scratch assays, solutions of continuum reaction-diffusion models have been calibrated to data from scratch assays. These models typically include a logistic source term to describe carrying capacity-limited proliferation; however, the choice of using a logistic source term is often made without examining whether it is valid. Here we study the proliferation of PC-3 prostate cancer cells in a scratch assay. All experimental results for the scratch assay are compared with equivalent results from a proliferation assay where the cell monolayer is not scratched. Visual inspection of the time evolution of the cell density away from the location of the scratch reveals a series of sigmoid curves that could be naively calibrated to the solution of the logistic growth model. However, careful analysis of the per capita growth rate as a function of density reveals several key differences between the proliferation of cells in scratch and proliferation assays. Our findings suggest that the logistic growth model is valid for the entire duration of the proliferation assay. On the other hand, guided by data, we suggest that there are two phases of proliferation in a scratch assay; at short time, we have a disturbance phase where proliferation is not logistic, and this is followed by a growth phase where proliferation appears to be logistic. These two phases are observed across a large number of experiments performed at different initial cell densities. Overall our study shows that simply calibrating the solution of a continuum model to a scratch assay might produce misleading parameter estimates, and this issue can be resolved by making a distinction between the

  1. Simvastatin induces cell cycle arrest and inhibits proliferation of bladder cancer cells via PPARγ signalling pathway

    PubMed Central

    Wang, Gang; Cao, Rui; Wang, Yongzhi; Qian, Guofeng; Dan, Han C.; Jiang, Wei; Ju, Lingao; Wu, Min; Xiao, Yu; Wang, Xinghuan

    2016-01-01

    Simvastatin is currently one of the most common drugs for old patients with hyperlipidemia, hypercholesterolemia and atherosclerotic diseases by reducing cholesterol level and anti-lipid properties. Importantly, simvastatin has also been reported to have anti-tumor effect, but the underlying mechanism is largely unknown. We collected several human bladder samples and performed microarray. Data analysis suggested bladder cancer (BCa) was significantly associated with fatty acid/lipid metabolism via PPAR signalling pathway. We observed simvastatin did not trigger BCa cell apoptosis, but reduced cell proliferation in a dose- and time-dependent manner, accompanied by PPARγ-activation. Moreover, flow cytometry analysis indicated that simvastatin induced cell cycle arrest at G0/G1 phase, suggested by downregulation of CDK4/6 and Cyclin D1. Furthermore, simvastatin suppressed BCa cell metastasis by inhibiting EMT and affecting AKT/GSK3β. More importantly, we found that the cell cycle arrest at G0/G1 phase and the alterations of CDK4/6 and Cyclin D1 triggered by simvastatin could be recovered by PPARγ-antagonist (GW9662), whereas the treatment of PPARα-antagonist (GW6471) shown no significant effects on the BCa cells. Taken together, our study for the first time revealed that simvastatin inhibited bladder cancer cell proliferation and induced cell cycle arrest at G1/G0 phase via PPARγ signalling pathway. PMID:27779188

  2. Software for precise tracking of cell proliferation

    SciTech Connect

    Kurokawa, Hiroshi; Noda, Hisayori; Sugiyama, Mayu; Sakaue-Sawano, Asako; Fukami, Kiyoko; Miyawaki, Atsushi

    2012-01-20

    Highlights: Black-Right-Pointing-Pointer We developed software for analyzing cultured cells that divide as well as migrate. Black-Right-Pointing-Pointer The active contour model (Snakes) was used as the core algorithm. Black-Right-Pointing-Pointer The time backward analysis was also used for efficient detection of cell division. Black-Right-Pointing-Pointer With user-interactive correction functions, the software enables precise tracking. Black-Right-Pointing-Pointer The software was successfully applied to cells with fluorescently-labeled nuclei. -- Abstract: We have developed a multi-target cell tracking program TADOR, which we applied to a series of fluorescence images. TADOR is based on an active contour model that is modified in order to be free of the problem of locally optimal solutions, and thus is resistant to signal fluctuation and morphological changes. Due to adoption of backward tracing and addition of user-interactive correction functions, TADOR is used in an off-line and semi-automated mode, but enables precise tracking of cell division. By applying TADOR to the analysis of cultured cells whose nuclei had been fluorescently labeled, we tracked cell division and cell-cycle progression on coverslips over an extended period of time.

  3. NFATc1 balances quiescence and proliferation of skin stem cells

    PubMed Central

    Horsley, Valerie; Aliprantis, Antonios O.; Polak, Lisa; Glimcher, Laurie H.; Fuchs, Elaine

    2008-01-01

    Quiescent adult stem cells reside in specialized niches where they become activated to proliferate and differentiate during tissue homeostasis and injury. How stem cell quiescence is governed is poorly understood. We report here that NFATc1 is preferentially expressed by hair follicle stem cells in their niche, where it's expression is activated by BMP signaling upstream and it acts downstream to transcriptionally repress CDK4 and maintain stem cell quiescence. As stem cells become activated during hair growth, NFATc1 is downregulated, relieving CDK4 repression and activating proliferation. When calcineurin/NFATc1 signaling is suppressed, pharmacologically or via complete or conditional NFATc1 gene ablation, stem cells are activated prematurely, resulting in precocious follicular growth. Our findings may explain why patients receiving cyclosporine A for immunosuppressive therapy display excessive hair growth, and unveil a functional role for calcium-NFATc1-CDK4 circuitry in governing stem cell quiescence. PMID:18243104

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

    PubMed

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

    2016-01-07

    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.

  5. Pup exposure elicits hippocampal cell proliferation in the prairie vole.

    PubMed

    Ruscio, Michael G; Sweeny, Timothy D; Hazelton, Julie L; Suppatkul, Patrin; Boothe, Emily; Carter, C Sue

    2008-02-11

    The onset of parental behavior has profound and enduring effects on behavior and neurobiology across a variety of species. In some cases, mere exposure to a foster neonate (and a subsequent parental response) can have similar effects. In the present experiment, we exposed adult male and female prairie voles (Microtus ochrogaster) to two foster pups for 20 min and quantified cell proliferation in the dentate gyrus of the hippocampus (DG), medial amygdala (MeA) and cortical amygdala (CorA). Prairie voles are highly social rodents that typically display biparental care and spontaneous parental care when exposed to foster pups. Comparisons were made between the animals that responded parentally or non-parentally towards the pups, as well as control conditions. Cell proliferation was assessed using injections of 5-bromo-2'-deoxyuridine (BrdU) and immunocytochemical localization of this marker. The phenotype of the cells was determined using double label immunofluoresence for BrdU and TuJ1 (a neuronal marker). An increase in cell proliferation in the DG was seen in animals exposed to pups. However, animals that responded non-parentally had a greater number of BrdU labeled cells in the DG compared to those that responded parentally. The majority of BrdU labeled cells co-expressed TuJ1 across all groups. These results demonstrate that exposure to a foster pup and the behavioral reaction to it (parental or non-parental) are associated with site-specific changes in cell proliferation.

  6. Lysophosphatidic Acid Up-Regulates Hexokinase II and Glycolysis to Promote Proliferation of Ovarian Cancer Cells.

    PubMed

    Mukherjee, Abir; Ma, Yibao; Yuan, Fang; Gong, Yongling; Fang, Zhenyu; Mohamed, Esraa M; Berrios, Erika; Shao, Huanjie; Fang, Xianjun

    2015-09-01

    Lysophosphatidic acid (LPA), a blood-borne lipid mediator, is present in elevated concentrations in ascites of ovarian cancer patients and other malignant effusions. LPA is a potent mitogen in cancer cells. The mechanism linking LPA signal to cancer cell proliferation is not well understood. Little is known about whether LPA affects glucose metabolism to accommodate rapid proliferation of cancer cells. Here we describe that in ovarian cancer cells, LPA enhances glycolytic rate and lactate efflux. A real time PCR-based miniarray showed that hexokinase II (HK2) was the most dramatically induced glycolytic gene to promote glycolysis in LPA-treated cells. Analysis of the human HK2 gene promoter identified the sterol regulatory element-binding protein as the primary mediator of LPA-induced HK2 transcription. The effects of LPA on HK2 and glycolysis rely on LPA2, an LPA receptor subtype overexpressed in ovarian cancer and many other malignancies. We further examined the general role of growth factor-induced glycolysis in cell proliferation. Like LPA, epidermal growth factor (EGF) elicited robust glycolytic and proliferative responses in ovarian cancer cells. Insulin-like growth factor 1 (IGF-1) and insulin, however, potently stimulated cell proliferation but only modestly induced glycolysis. Consistent with their differential effects on glycolysis, LPA and EGF-dependent cell proliferation was highly sensitive to glycolytic inhibition while the growth-promoting effect of IGF-1 or insulin was more resistant. These results indicate that LPA- and EGF-induced cell proliferation selectively involves up-regulation of HK2 and glycolytic metabolism. The work is the first to implicate LPA signaling in promotion of glucose metabolism in cancer cells.

  7. Intermittent individual housing increases survival of newly proliferated cells.

    PubMed

    Aberg, Elin; Pham, Therese M; Zwart, Mieke; Baumans, Vera; Brené, Stefan

    2005-09-08

    In this study, we analyzed how intermittent individual housing with or without a running wheel influenced corticosterone levels and survival of newly proliferated cells in the dentate gyrus of the hippocampus. Female Balb/c mice, in standard or enhanced housing, were divided into groups that were individually housed with or without running wheels on every second day. Intermittent individual housing without, but not with, running wheels increased survival of proliferated cells in the dentate gyrus as compared with continuous group housing in standard or enhanced conditions. Thus, changes in housing conditions on every second day can, under certain circumstances, have an impact on the survival of newly proliferated cells in the dentate gyrus.

  8. Yangjing Capsule Extract Promotes Proliferation of GC-1 Spg Cells

    PubMed Central

    Wang, Zhiqiang; Jin, Baofang; Zhang, Xindong; Cui, Yugui; Sun, Dalin; Gao, Chao

    2014-01-01

    Objective. To investigate the effect of Yangjing Capsule (YC) extract on proliferation of GC-1 spermatogonia (spg) cells and the mechanism. Methods. GC-1 spg cells were treated with 0.01, 0.1, and 1 mg/mL YC extract. MTT assay was performed to detect the cell viability. Flow cytometry was used to measure the cell cycle and apoptosis of GC-1 spg cells. Real-time PCR and western blot were applied to determine the mRNA and protein expression of Oct-4 and Plzf. Gfrα1 knockdown and LY294002 (PI3K inhibitor) were applied to explore the underlying mechanism. Results. After 48 h treatment of YC, the viability of GC-1 spg cells increased significantly and the ratio of apoptotic cells reduced significantly. The increased mRNA and protein expression of Oct-4 and Plzf suggested YC promoted self-renewal of GC-1 spg cells. Both Gfrα1 siRNAs and LY294002 treatments held back YC extract's stimulation effects on mRNA and protein expression of Oct-4 and Plzf and consequently inhibited the proliferation of GC-1 spg cells induced by YC extract. Conclusion. YC extract could stimulate the proliferation of GC-1 spg cells. Partly via Gfrα1, YC extract is able to trigger the activation of PI3K pathway and finally lead to self-renewal of GC-1 spg cells. PMID:24817900

  9. Lipoteichoic acids from Staphylococcus aureus stimulate proliferation of human non-small-cell lung cancer cells in vitro.

    PubMed

    Hattar, Katja; Reinert, Christian P; Sibelius, Ulf; Gökyildirim, Mira Y; Subtil, Florentine S B; Wilhelm, Jochen; Eul, Bastian; Dahlem, Gabriele; Grimminger, Friedrich; Seeger, Werner; Grandel, Ulrich

    2017-03-17

    Pulmonary infections are frequent complications in lung cancer and may worsen its outcome and survival. Inflammatory mediators are suspected to promote tumor growth in non-small-cell lung cancer (NSCLC). Hence, bacterial pathogens may affect lung cancer growth by activation of inflammatory signalling. Against this background, we investigated the effect of purified lipoteichoic acids (LTA) of Staphylococcus aureus (S. aureus) on cellular proliferation and liberation of interleukin (IL)-8 in the NSCLC cell lines A549 and H226. A549 as well as H226 cells constitutively expressed TLR-2 mRNA. Even in low concentrations, LTA induced a prominent increase in cellular proliferation of A549 cells as quantified by automatic cell counting. In parallel, metabolic activity of A549 cells was enhanced. The increase in proliferation was accompanied by an increase in IL-8 mRNA expression and a dose- and time-dependent release of IL-8. Cellular proliferation as well as the release of IL-8 was dependent on specific ligation of TLR-2. Interestingly, targeting IL-8 by neutralizing antibodies completely abolished the LTA-induced proliferation of A549 cells. The pro-proliferative effect of LTA could also be reproduced in the squamous NSCLC cell line H226. In summary, LTA of S. aureus induced proliferation of NSCLC cell lines of adeno- and squamous cell carcinoma origin. Ligation of TLR-2 followed by auto- or paracrine signalling by endogenously synthesized IL-8 is centrally involved in LTA-induced tumor cell proliferation. Therefore, pulmonary infections may exert a direct pro-proliferative effect on lung cancer growth.

  10. Fluidic control over cell proliferation and chemotaxis

    NASA Astrophysics Data System (ADS)

    Groisman, Alex

    2006-03-01

    Microscopic flows are almost always stable and laminar that allows precise control of chemical environment in micro-channels. We describe design and operation of several microfluidic devices, in which various types of environments are created for different experimental assays with live cells. In a microfluidic chemostat, colonies of non-adherent bacterial and yeast cells are trapped in micro-chambers with walls permeable for chemicals. Fast chemical exchange between the chambers and nearby flow-through channels creates essentially chemostatic medium conditions in the chambers and leads to exponential growth of the colonies up to very high cell densities. Another microfluidic device allows creation of linear concentration profiles of a pheromone (α-factor) across channels with non-adherent yeast cells, without exposure of the cells to flow or other mechanical perturbation. The concentration profile remains stable for hours enabling studies of chemotropic response of the cells to the pheromone gradient. A third type of the microfluidic devices is used to study chemotaxis of human neutrophils exposed to gradients of a chemoattractant (fMLP). The devices generate concentration profiles of various shapes, with adjustable steepness and mean concentration. The ``gradient'' of the chemoattractant can be imposed and reversed within less than a second, allowing repeated quantitative experiments.

  11. Elimination of proliferating cells from CNS grafts using a Ki67 promoter-driven thymidine kinase

    PubMed Central

    Tieng, Vannary; Cherpin, Ophelie; Gutzwiller, Eveline; Zambon, Alexander C; Delgado, Christophe; Salmon, Patrick; Dubois-Dauphin, Michel; Krause, Karl-Heinz

    2016-01-01

    Pluripotent stem cell (PSC)-based cell therapy is an attractive concept for neurodegenerative diseases, but can lead to tumor formation. This is particularly relevant as proliferating neural precursors rather than postmitotic mature neurons need to be transplanted. Thus, safety mechanisms to eliminate proliferating cells are needed. Here, we propose a suicide gene approach, based on cell cycle-dependent promoter Ki67-driven expression of herpes simplex virus thymidine kinase (HSV-TK). We generated a PSC line expressing this construct and induced neural differentiation. In vitro, proliferating PSC and early neural precursor cells (NPC) were killed by exposure to ganciclovir. In vivo, transplantation of PSC led to tumor formation, which was prevented by early ganciclovir treatment. Transplanted NPC did not lead to tumor formation and their survival and neural maturation were not affected by ganciclovir. In conclusion, the cell cycle promoter-driven suicide gene approach described in this study allows killing of proliferating undifferentiated precursor cells without expression of the suicide gene in mature neurons. This approach could also be of use for other stem cell-based therapies where the final target consists of postmitotic cells. PMID:27990449

  12. Stabilization of telomeres in nonlinear models of proliferating cell lines.

    PubMed

    Dyson, Janet; Sánchez, Eva; Villella-Bressan, Rosanna; Webb, Glenn F

    2007-02-07

    We analyse an age-structured model of telomere loss in a proliferating cell population. The cell population is divided into telomere classes, which shorten each round of division. The model consists of a nonlinear system of partial differential equations for the telomere classes. We prove that if the highest telomere class is exempted from mortality, then all the classes stabilize to a nontrivial equilibrium dependent on the initial state of cells in the highest telomere class.

  13. Control of cell proliferation in human glioma by glucocorticoids.

    PubMed

    Freshney, R I; Sherry, A; Hassanzadah, M; Freshney, M; Crilly, P; Morgan, D

    1980-06-01

    Survival and proliferation of cell cultures from human anaplastic astrocytomas were shown to be enhanced by glucocorticoids with an optimal concentration of approximately 2.5 x 10(-5)M (10 micrograms/ml). The stimulation of proliferation was only observed in a clonal growth assay and was reversed as the size of individual colonies reached approximately 50 cells. Above this size, and in regular monolayer cultures, glucocorticoids were found to inhibit cell proliferation as measured by direct cell counting and incorporation of [3H] thymidine. Cultures grown to maximum cell densities in non-limiting medium conditions reached a lower terminal cell density, and had a reduced labelling index with [3H] thymidine in the presence of glucocorticoids. Although there was little difference between the actions of beta-methasone, dexamethasone and ethyl prednisolone, methyl prednisolone was found to be more effective, both in terms of stimulation of clonal growth and inhibition of growth at high cell densities. There was no evidence of cytotoxicity with glucocorticoids up to 5 x 10(-5)M (20 micrograms/ml) and it is suggested that glucocorticoids act via a normal regulatory process, perhaps enhancing cell-cell recognition.

  14. Control of cell proliferation in human glioma by glucocorticoids.

    PubMed Central

    Freshney, R. I.; Sherry, A.; Hassanzadah, M.; Freshney, M.; Crilly, P.; Morgan, D.

    1980-01-01

    Survival and proliferation of cell cultures from human anaplastic astrocytomas were shown to be enhanced by glucocorticoids with an optimal concentration of approximately 2.5 x 10(-5)M (10 micrograms/ml). The stimulation of proliferation was only observed in a clonal growth assay and was reversed as the size of individual colonies reached approximately 50 cells. Above this size, and in regular monolayer cultures, glucocorticoids were found to inhibit cell proliferation as measured by direct cell counting and incorporation of [3H] thymidine. Cultures grown to maximum cell densities in non-limiting medium conditions reached a lower terminal cell density, and had a reduced labelling index with [3H] thymidine in the presence of glucocorticoids. Although there was little difference between the actions of beta-methasone, dexamethasone and ethyl prednisolone, methyl prednisolone was found to be more effective, both in terms of stimulation of clonal growth and inhibition of growth at high cell densities. There was no evidence of cytotoxicity with glucocorticoids up to 5 x 10(-5)M (20 micrograms/ml) and it is suggested that glucocorticoids act via a normal regulatory process, perhaps enhancing cell-cell recognition. Images Fig. 2 Fig. 3 PMID:7426310

  15. miR-126 inhibits non-small cell lung cancer cells proliferation by targeting EGFL7

    SciTech Connect

    Sun, Yanqin; Bai, Yifeng; Zhang, Fan; Wang, Yu; Guo, Ying; Guo, Linlang

    2010-01-15

    MicroRNAs (miRNAs) represent an abundant group of small non-coding RNAs that regulate gene expression, and have been demonstrated to play roles as tumor suppressor genes (oncogenes), and affect homeostatic processes such as development, cell proliferation, and cell death. Subsequently, epidermal growth factor-like domain 7 (EGFL7), which is confirmed to be involved in cellular responses such as cell migration and blood vessel formation, is identified as a potential miR-126 target by bioinformatics. However, there is still no evidence showing EGFL7's relationship with miR-126 and the proliferation of lung cancer cells. The aim of this work is to investigate whether miR-126, together with EGFL7, have an effect on non-small cell lung cancer (NSCLC) cells' proliferation. Therefore, we constructed overexpressed miR-126 plasmid to target EGFL7 and transfected them into NSCLC cell line A549 cells. Then, we used methods like quantitative RT-PCR, Western blot, flow cytometry assay, and immunohistochemistry staining to confirm our findings. The result was that overexpression of miR-126 in A549 cells could increase EGFL7 expression. Furthermore, the most notable finding by cell proliferation related assays is that miR-126 can inhibit A549 cells proliferation in vitro and inhibit tumor growth in vivo by targeting EGFL7. As a result, our study demonstrates that miR-126 can inhibit proliferation of non-small cell lung cancer cells through one of its targets, EGFL7.

  16. Thermal manipulation during embryogenesis affects myoblast proliferation and skeletal muscle growth in meat-type chickens.

    PubMed

    Piestun, Yogev; Yahav, Shlomo; Halevy, Orna

    2015-10-01

    Thermal manipulation (TM) of 39.5°C applied during mid-embryogenesis (embryonic d 7 to 16) has been proven to promote muscle development and enhance muscle growth and meat production in meat-type chickens. This study aimed to elucidate the cellular basis for this effect. Continuous TM or intermittent TM (for 12 h/d) increased myoblast proliferation manifested by higher (25 to 48%) myoblast number in the pectoral muscles during embryonic development but also during the first week posthatch. Proliferation ability of the pectoral-muscle-derived myoblasts in vitro was significantly higher in the TM treatments until embryonic d 15 (intermittent TM) or 13 (continuous TM) compared to that of controls, suggesting increased myogenic progeny reservoir in the muscle. However, the proliferation ability of myoblasts was lower in the TM treatments vs. control during the last days of incubation. This coincided with higher levels of myogenin expression in the muscle, indicating enhanced cell differentiation in the TM muscle. A similar pattern was observed posthatch: Myoblast proliferation was significantly higher in the TM chicks relative to controls during the peak of posthatch cell proliferation until d 6, followed by lower cell number 2 wk posthatch as myoblast number sharply decreases. Higher myogenin expression was observed in the TM chicks on d 6. This resulted in increased muscle growth, manifested by significantly higher relative weight of breast muscle in the embryo and posthatch. It can be concluded that temperature elevation during mid-term embryogenesis promotes myoblast proliferation, thus increasing myogenic progeny reservoir in the muscle, resulting in enhanced muscle growth in the embryo and posthatch.

  17. VUV modification promotes endothelial cell proliferation on PTFE vascular grafts

    NASA Astrophysics Data System (ADS)

    Cezeaux, J. L.; Romoser, C. E.; Benson, R. S.; Buck, C. K.; Sackman, J. E.

    1998-05-01

    Small diameter (⩽6 mm ID ) synthetic vascular grafts, used as lower-limb vessel replacements in patients without suitable autologous saphenous veins, have a failure rate of 53% after 4 yr. Graft failure is due to thrombosis and intimal hyperplasia, an increase in smooth muscle cells in the lumen of the vessel which leads to progressive closing and ultimate occlusion of the vessel. In an effort to increase patency rates of synthetic grafts, investigators have seeded vascular grafts with endothelial cells prior to implantation in an attempt to control both thrombosis and smooth muscle proliferation. This technique has been successful for the development of an endothelial monolayer in animal trials, but has met with limited success in humans. The hydrophobicity, low surface energy, and weak electrical charge of expanded polytetrafluoroethylene (ePTFE) provides conditions which are not optimal for endothelial cell attachment. The purpose of this study is to evaluate the effect of vacuum ultraviolet (VUV) modification of ePTFE on endothelial cell adhesion and proliferation. Pieces of ePTFE graft material were exposed to 10, 20 or 40 W VUV radiation for 10, 20 or 40 min using a UV excimer lamp. Prior to cell adhesion and proliferation experiments, the grafts pieces were autoclaved and cut into pledgets. Half of the pledgets were precoated with fibronectin ( 20 μg/ml). Cell adhesion was measured by seeding 3H-thymidine labeled human umbilical vein endothelial cells (HUVEC) onto the pledgets for 60 min. The pledgets were then washed and the remaining radioactivity assayed using scintillation counting. For the cell proliferation experiments, pledgets were seeded with unlabeled HUVEC which were allowed to adhere to the graft material for 18 h. The cells were then exposed to 3H-thymidine ( 1 μCi/ml) for approximately 48 h and then washed to remove any unincorporated 3H-thymidine. Incorporation of 3H-thymidine was measured using scintillation counting. Four replicate

  18. Hedgehog signaling plays roles in epithelial cell proliferation in neonatal mouse uterus and vagina.

    PubMed

    Nakajima, Tadaaki; Iguchi, Taisen; Sato, Tomomi

    2012-04-01

    Both the uterus and vagina develop from the Müllerian duct but are quite distinct in morphology and function. To investigate factors controlling epithelial differentiation and cell proliferation in neonatal uterus and vagina, we focused on Hedgehog (HH) signaling. In neonatal mice, Sonic hh (Shh) was localized in the vaginal epithelium and Indian hh (Ihh) was slightly expressed in the uterus and vagina, whereas all Glioma-associated oncogene homolog (Gli) genes were mainly expressed in the stroma. The expression of target genes of HH signaling was high in the neonatal vagina and in the uterus, it increased with growth. Thus, in neonatal mice, Shh in the vaginal epithelium and Ihh in the uterus and vagina activated HH signaling in the stroma. Tissue recombinants showed that vaginal Shh expression was inhibited by the vaginal stroma and uterine Ihh expression was stimulated by the uterine stroma. Addition of a HH signaling inhibitor decreased epithelial cell proliferation in organ-cultured uterus and vagina and increased stromal cell proliferation in organ-cultured uterus. However, it did not affect epithelial differentiation or the expression of growth factors in organ-cultured uterus and vagina. Thus, activated HH signaling stimulates epithelial cell proliferation in neonatal uterus and vagina but inhibits stromal cell proliferation in neonatal uterus.

  19. FOXL2-induced follistatin attenuates activin A-stimulated cell proliferation in human granulosa cell tumors

    SciTech Connect

    Cheng, Jung-Chien; Chang, Hsun-Ming; Qiu, Xin; Fang, Lanlan; Leung, Peter C.K.

    2014-01-10

    Highlights: •Activin A stimulates cell proliferation in KGN human granulosa cell tumor-derived cell line. •Cyclin D2 mediates activin A-induced KGN cell proliferation. •FOXL2 induces follistatin expression in KGN cells. •FOXL2-induced follistatin attenuates activin A-stimulated KGN cell proliferation. -- Abstract: Human granulosa cell tumors (GCTs) are rare, and their etiology remains largely unknown. Recently, the FOXL2 402C > G (C134W) mutation was found to be specifically expressed in human adult-type GCTs; however, its function in the development of human GCTs is not fully understood. Activins are members of the transforming growth factor-beta superfamily, which has been shown to stimulate normal granulosa cell proliferation; however, little is known regarding the function of activins in human GCTs. In this study, we examined the effect of activin A on cell proliferation in the human GCT-derived cell line KGN. We show that activin A treatment stimulates KGN cell proliferation. Treatment with the activin type I receptor inhibitor SB431542 blocks activin A-stimulated cell proliferation. In addition, our results show that cyclin D2 is induced by treatment with activin A and is involved in activin A-stimulated cell proliferation. Moreover, the activation of Smad signaling is required for activin A-induced cyclin D2 expression. Finally, we show that the overexpression of the wild-type FOXL2 but not the C134W mutant FOXL2 induced follistatin production. Treatment with exogenous follistatin blocks activin A-stimulated cell proliferation, and the overexpression of wild-type FOXL2 attenuates activin A-stimulated cell proliferation. These results suggest that FOXL2 may act as a tumor suppressor in human adult-type GCTs by inducing follistatin expression, which subsequently inhibits activin-stimulated cell proliferation.

  20. MicroRNA regulation of myogenic satellite cell proliferation and differentiation.

    PubMed

    Harding, Rachel L; Velleman, Sandra G

    2016-01-01

    Myogenic satellite cells are stem cells responsible for muscle growth and regeneration. MicroRNAs (miRNAs) play significant roles in regulating numerous cellular processes. Two genes essential to satellite cell function are syndecan-4 and glypican-1. To determine if miRNAs influence myogenic satellite cell function, one miRNA predicted to bind syndecan-4 (miR-128) and two predicted to bind glypican-1 (miR-24 and miR-16) were inhibited in vitro by transfection of inhibitors targeting each miRNA. Inhibition of these miRNAs differentially affected the expression of syndecan-4, glypican-1, and myogenic regulatory factors myoD and myogenin. Inhibition of miR-16 reduced proliferation of satellite cells at 72 h. Inhibition of miR-128 and miR-24 did not affect proliferation. Inhibition of miRNAs reduced differentiation of satellite cells into myotubes at 48 and 72 h except for miR-16, which only affected differentiation at 72 h. Inhibition of all three miRNAs decreased myotube width at 24 h of differentiation and increased myotube width at 48 h of differentiation. Inhibiting these miRNAs also increased the number of nuclei per myotube at 72 h of differentiation. These data demonstrate individual miRNAs regulate genes essential for myogenic satellite cell proliferation and differentiation.

  1. Small-molecule targeting of proliferating cell nuclear antigen chromatin association inhibits tumor cell growth.

    PubMed

    Tan, Zongqing; Wortman, Matthew; Dillehay, Kelsey L; Seibel, William L; Evelyn, Chris R; Smith, Shanna J; Malkas, Linda H; Zheng, Yi; Lu, Shan; Dong, Zhongyun

    2012-06-01

    Proliferating cell nuclear antigen (PCNA), a potential anticancer target, forms a homotrimer and is required for DNA replication and numerous other cellular processes. The purpose of this study was to identify novel small molecules that modulate PCNA activity to affect tumor cell proliferation. An in silico screen of a compound library against a crystal structure of PCNA and a subsequent structural similarity search of the ZINC chemical database were carried out to derive relevant docking partners. Nine compounds, termed PCNA inhibitors (PCNA-Is), were selected for further characterization. PCNA-I1 selectively bound to PCNA trimers with a dissociation constant (K(d)) of ~0.2 to 0.4 μM. PCNA-Is promoted the formation of SDS-refractory PCNA trimers. PCNA-I1 dose- and time-dependently reduced the chromatin-associated PCNA in cells. Consistent with its effects on PCNA trimer stabilization, PCNA-I1 inhibited the growth of tumor cells of various tissue types with an IC(50) of ~0.2 μM, whereas it affected the growth of nontransformed cells at significantly higher concentrations (IC(50), ~1.6 μM). Moreover, uptake of BrdU was dose-dependently reduced in cells treated with PCNA-I1. Mechanistically the PCNA-Is mimicked the effect of PCNA knockdown by siRNA, inducing cancer cell arrest at both the S and G(2)/M phases. Thus, we have identified a class of compounds that can directly bind to PCNA, stabilize PCNA trimers, reduce PCNA association with chromatin, and inhibit tumor cell growth by inducing a cell cycle arrest. They are valuable tools in studying PCNA function and may be useful for future PCNA-targeted cancer therapy.

  2. Repression of cell proliferation by miR319-regulated TCP4.

    PubMed

    Schommer, Carla; Debernardi, Juan M; Bresso, Edgardo G; Rodriguez, Ramiro E; Palatnik, Javier F

    2014-10-01

    Leaf development has been extensively studied on a genetic level. However, little is known about the interplay between the developmental regulators and the cell cycle machinery--a link that ultimately affects leaf form and size. miR319 is a conserved microRNA that regulates TCP transcription factors involved in multiple developmental pathways, including leaf development and senescence, organ curvature, and hormone biosynthesis and signaling. Here, we analyze the participation of TCP4 in the control of cell proliferation. A small increase in TCP4 activity has an immediate impact on leaf cell number, by significantly reducing cell proliferation. Plants with high TCP4 levels have a strong reduction in the expression of genes known to be active in G2-M phase of the cell cycle. Part of these effects is mediated by induction of miR396, which represses Growth-Regulating Factor (GRF) transcription factors. Detailed analysis revealed TCP4 to be a direct regulator of MIR396b. However, we found that TCP4 can control cell proliferation through additional pathways, and we identified a direct connection between TCP4 and ICK1/KRP1, a gene involved in the progression of the cell cycle. Our results show that TCP4 can activate different pathways that repress cell proliferation.

  3. Boric acid inhibits human prostate cancer cell proliferation.

    PubMed

    Barranco, Wade T; Eckhert, Curtis D

    2004-12-08

    The role of boron in biology includes coordinated regulation of gene expression in mixed bacterial populations and the growth and proliferation of higher plants and lower animals. Here we report that boric acid, the dominant form of boron in plasma, inhibits the proliferation of prostate cancer cell lines, DU-145 and LNCaP, in a dose-dependent manner. Non-tumorigenic prostate cell lines, PWR-1E and RWPE-1, and the cancer line PC-3 were also inhibited, but required concentrations higher than observed human blood levels. Studies using DU-145 cells showed that boric acid induced a cell death-independent proliferative inhibition, with little effect on cell cycle stage distribution and mitochondrial function.

  4. Cdk4 deficiency inhibits skin tumor development but does not affect normal keratinocyte proliferation.

    PubMed

    Rodriguez-Puebla, Marcelo L; Miliani de Marval, Paula L; LaCava, Margaret; Moons, David S; Kiyokawa, Hiroaki; Conti, Claudio J

    2002-08-01

    Most human tumors have mutations that result in deregulation of the cdk4/cyclin-Ink4-Rb pathway. Overexpression of D-type cyclins or cdk4 and inactivation of Ink4 inhibitors are common in human tumors. Conversely, lack of cyclin D1 expression results in significant reduction in mouse skin and mammary tumor development. However, complete elimination of tumor development was not observed in these models, suggesting that other cyclin/cdk complexes play an important role in tumorigenesis. Here we described the effects of cdk4 deficiency on mouse skin proliferation and tumor development. Cdk4 deficiency resulted in a 98% reduction in the number of tumors generated through the two-stage carcinogenesis model. The absence of cdk4 did not affect normal keratinocyte proliferation and both wild-type and cdk4 knockout epidermis are equally affected after topical treatment with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA), resulting in epidermal hyperplasia. In similar fashion, cdk4 knockout keratinocytes proliferated well in an in vivo model of wound-induced proliferation. Biochemical studies in mouse epidermis showed that cdk6 activity increased twofold in cdk4-deficient mice compared to wild-type siblings. These results suggest that therapeutic approaches to inhibit cdk4 activity could provide a target to inhibit tumor development with minimal or no effect in normal tissue.

  5. Wnt5a promotes cancer cell invasion and proliferation by receptor-mediated endocytosis-dependent and -independent mechanisms, respectively

    PubMed Central

    Shojima, Kensaku; Sato, Akira; Hanaki, Hideaki; Tsujimoto, Ikuko; Nakamura, Masahiro; Hattori, Kazunari; Sato, Yuji; Dohi, Keiji; Hirata, Michinari; Yamamoto, Hideki; Kikuchi, Akira

    2015-01-01

    Wnt5a activates the Wnt/β-catenin-independent pathway and its overexpression is associated with tumor aggressiveness enhancing invasive activity. For this action, Wnt5a-induced receptor endocytosis with clathrin is required. Wnt5a expression was previously believed to be associated with cancer cell motility but not proliferation. Recently, it was reported that Wnt5a is also implicated in cancer cell proliferation, but the mechanism was not clear. In this study, we generated a neutralizing anti-Wnt5a monoclonal antibody (mAb5A16) to investigate the mechanism by which Wnt5a regulates cancer cell proliferation. Wnt5a stimulated both invasion and proliferation of certain types of cancer cells, including HeLaS3 cervical cancer cells and A549 lung cancer cells although Wnt5a promoted invasion but not proliferation in other cancer cells such as KKLS gastric cancer cells. mAb5A16 did not affect the binding of Wnt5a to its receptor, but it suppressed Wnt5a-induced receptor-mediated endocytosis. mAb5A16 inhibited invasion but not proliferation of HeLaS3 and A549 cells. Wnt5a activated Src family kinases (SFKs) and Wnt5a-dependent cancer cell proliferation was dependent on SFKs, yet blockade of receptor-mediated endocytosis did not affect cancer cell proliferation and SFK activity. These results suggest that Wnt5a promotes invasion and proliferation of certain types of cancer cells through receptor-mediated endocytosis-dependent and -independent mechanisms, respectively. PMID:25622531

  6. Lyn tyrosine kinase regulates thrombopoietin-induced proliferation of hematopoietic cell lines and primary megakaryocytic progenitors.

    PubMed

    Lannutti, Brian J; Drachman, Jonathan G

    2004-05-15

    In this study we demonstrate that thrombopoietin (TPO)-stimulated Src family kinases (SFKs) inhibit cellular proliferation and megakaryocyte differentiation. Using the Src kinase inhibitors pyrolopyrimidine 1 and 2 (PP1, PP2), we show that TPO-dependent proliferation of BaF3/Mpl cells was enhanced at concentrations that are specific for SFKs. Similarly, proliferation is increased after introducing a dominant-negative form of Lyn into BaF3/Mpl cells. Murine marrow cells from Lyn-deficient mice or wild-type mice cultured in the presence of the Src inhibitor, PP1, yielded a greater number of mature megakaryocytes and increased nuclear ploidy. Truncation and targeted mutation of the Mpl cytoplasmic domain indicate that Y112 is critical for Lyn activation. Examining the molecular mechanism for this antiproliferative effect, we determined that SFK inhibitors did not affect tyrosine phosphorylation of Janus kinase 2 (JAK2), Shc, signal transducer and activator of transcription (STAT)5, or STAT3. In contrast, pretreatment of cells with PP2 increased Erk1/2 (mitogen-activated protein kinase [MAPK]) phosphorylation and in vitro kinase activity, particularly after prolonged TPO stimulation. Taken together, our results show that Mpl stimulation results in the activation of Lyn kinase, which appears to limit the proliferative response through a signaling cascade that regulates MAPK activity. These data suggest that SFKs modify the rate of TPO-induced proliferation and are likely to affect cell cycle regulation during megakaryocytopoiesis.

  7. The Cancer-Related Transcription Factor Runx2 Modulates Cell Proliferation in Human Osteosarcoma Cell Lines

    PubMed Central

    Lucero, Claudia M.J.; Vega, Oscar A.; Osorio, Mariana M.; Tapia, Julio C.; Antonelli, Marcelo; Stein, Gary S.; Van Wijnen, Andre J.; Galindo, Mario A.

    2013-01-01

    Runx2 regulates osteogenic differentiation and bone formation, but also suppresses pre-osteoblast proliferation by affecting cell cycle progression in the G1 phase. The growth suppressive potential of Runx2 is normally inactivated in part by protein destabilization, which permits cell cycle progression beyond the G1/S phase transition, and Runx2 is again up-regulated after mitosis. Runx2 expression also correlates with metastasis and poor chemotherapy response in osteosarcoma. Here we show that six human osteosarcoma cell lines (SaOS, MG63, U2OS, HOS, G292, and 143B) have different growth rates, which is consistent with differences in the lengths of the cell cycle. Runx2 protein levels are cell cycle-regulated with respect to the G1/S phase transition in U2OS, HOS, G292, and 143B cells. In contrast, Runx2 protein levels are constitutively expressed during the cell cycle in SaOS and MG63 cells. Forced expression of Runx2 suppresses growth in all cell lines indicating that accumulation of Runx2 in excess of its pre-established levels in a given cell type triggers one or more anti-proliferative pathways in osteosarcoma cells. Thus, regulatory mechanisms controlling Runx2 expression in osteosarcoma cells must balance Runx2 protein levels to promote its putative oncogenic functions, while avoiding suppression of bone tumor growth. PMID:22949168

  8. Autophagy is involved in aldosterone-induced mesangial cell proliferation

    PubMed Central

    Yang, Min; Wang, Bin; Miao, Liying; Xu, Xianlin; He, Xiaozhou

    2016-01-01

    The aim of the present study was to investigate whether autophagy is involved in aldosterone (Aldo)-induced mesangial cell (MC) proliferation. MCs were incubated with 10−7 M Aldo for 24 h. Proliferation of MCs, and the underlying mechanisms, were subsequently analyzed using [3H]thymidine assay, cell counting assay, western blotting and RNA interference (RNAi). Aldo was revealed to induce autophagy, as indicated by the increased conversion from microtubule-associated protein 1A/1B-light chain 3 (LC3)-I to LC3-II, the increased expression levels of autophagy-related gene 7 (Atg7) and the increased degradation of p62, which was accompanied by MC proliferation. Notably, pharmacological inhibition of autophagy or RNAi-mediated knockdown of Atg7 attenuated Aldo-induced MC proliferation, suggesting that autophagy was at least partially responsible for this effect. The results of the present study provided evidence that autophagy is critical for regulating Aldo-induced MC proliferation. PMID:27748808

  9. Fractal Dimensions of In Vitro Tumor Cell Proliferation

    PubMed Central

    Lambrou, George I.

    2015-01-01

    Biological systems are characterized by their potential for dynamic adaptation. One of the challenges for systems biology approaches is their contribution towards the understanding of the dynamics of a growing cell population. Conceptualizing these dynamics in tumor models could help us understand the steps leading to the initiation of the disease and its progression. In vitro models are useful in answering this question by providing information over the spatiotemporal nature of such dynamics. In the present work, we used physical quantities such as growth rate, velocity, and acceleration for the cellular proliferation and identified the fractal structures in tumor cell proliferation dynamics. We provide evidence that the rate of cellular proliferation is of nonlinear nature and exhibits oscillatory behavior. We also calculated the fractal dimensions of our cellular system. Our results show that the temporal transitions from one state to the other also follow nonlinear dynamics. Furthermore, we calculated self-similarity in cellular proliferation, providing the basis for further investigation in this topic. Such systems biology approaches are very useful in understanding the nature of cellular proliferation and growth. From a clinical point of view, our results may be applicable not only to primary tumors but also to tumor metastases. PMID:25883653

  10. Proliferation of the hyperthermophilic archaeon Pyrobaculum islandicum by cell fission.

    PubMed

    Sonobe, Seiji; Aoyama, Kazue; Suzuki, Chihiro; Saito, Ko-hei; Nagata, Kumiko; Shimmen, Teruo; Nagata, Yoko

    2010-07-01

    Pyrobaculum islandicum is a hyperthermophilic archaeon. P. islandicum cells have been suggested to multiply by constriction, budding and branching, as no septa were observed in cells by phase-contrast light microscopy. In this study, we observed the cells using transmission electron microscopy, scanning electron microscopy, and light microscopy with dark-field image analyses, and we report binary fission via septum formation to be the main mode of P. islandicum's proliferation. "Long cells" reported previously were found to comprise several cylindrical cells that align in tandem.

  11. Poisson-event-based analysis of cell proliferation.

    PubMed

    Summers, Huw D; Wills, John W; Brown, M Rowan; Rees, Paul

    2015-05-01

    A protocol for the assessment of cell proliferation dynamics is presented. This is based on the measurement of cell division events and their subsequent analysis using Poisson probability statistics. Detailed analysis of proliferation dynamics in heterogeneous populations requires single cell resolution within a time series analysis and so is technically demanding to implement. Here, we show that by focusing on the events during which cells undergo division rather than directly on the cells themselves a simplified image acquisition and analysis protocol can be followed, which maintains single cell resolution and reports on the key metrics of cell proliferation. The technique is demonstrated using a microscope with 1.3 μm spatial resolution to track mitotic events within A549 and BEAS-2B cell lines, over a period of up to 48 h. Automated image processing of the bright field images using standard algorithms within the ImageJ software toolkit yielded 87% accurate recording of the manually identified, temporal, and spatial positions of the mitotic event series. Analysis of the statistics of the interevent times (i.e., times between observed mitoses in a field of view) showed that cell division conformed to a nonhomogeneous Poisson process in which the rate of occurrence of mitotic events, λ exponentially increased over time and provided values of the mean inter mitotic time of 21.1 ± 1.2 hours for the A549 cells and 25.0 ± 1.1 h for the BEAS-2B cells. Comparison of the mitotic event series for the BEAS-2B cell line to that predicted by random Poisson statistics indicated that temporal synchronisation of the cell division process was occurring within 70% of the population and that this could be increased to 85% through serum starvation of the cell culture.

  12. Proliferation and cell cycle dynamics in the developing stellate ganglion.

    PubMed

    Gonsalvez, David G; Cane, Kylie N; Landman, Kerry A; Enomoto, Hideki; Young, Heather M; Anderson, Colin R

    2013-04-03

    Cell proliferation during nervous system development is poorly understood outside the mouse neocortex. We measured cell cycle dynamics in the embryonic mouse sympathetic stellate ganglion, where neuroblasts continue to proliferate following neuronal differentiation. At embryonic day (E) 9.5, when neural crest-derived cells were migrating and coalescing into the ganglion primordium, all cells were cycling, cell cycle length was only 10.6 h, and S-phase comprised over 65% of the cell cycle; these values are similar to those previously reported for embryonic stem cells. At E10.5, Sox10(+) cells lengthened their cell cycle to 38 h and reduced the length of S-phase. As cells started to express the neuronal markers Tuj1 and tyrosine hydroxylase (TH) at E10.5, they exited the cell cycle. At E11.5, when >80% of cells in the ganglion were Tuj1(+)/TH(+) neuroblasts, all cells were again cycling. Neuroblast cell cycle length did not change significantly after E11.5, and 98% of Sox10(-)/TH(+) cells had exited the cell cycle by E18.5. The cell cycle length of Sox10(+)/TH(-) cells increased during late embryonic development, and ∼25% were still cycling at E18.5. Loss of Ret increased neuroblast cell cycle length at E16.5 and decreased the number of neuroblasts at E18.5. A mathematical model generated from our data successfully predicted the relative change in proportions of neuroblasts and non-neuroblasts in wild-type mice. Our results show that, like other neurons, sympathetic neuron differentiation is associated with exit from the cell cycle; sympathetic neurons are unusual in that they then re-enter the cell cycle before later permanently exiting.

  13. Expression of the melanoma cell adhesion molecule in human mesenchymal stromal cells regulates proliferation, differentiation, and maintenance of hematopoietic stem and progenitor cells.

    PubMed

    Stopp, Sabine; Bornhäuser, Martin; Ugarte, Fernando; Wobus, Manja; Kuhn, Matthias; Brenner, Sebastian; Thieme, Sebastian

    2013-04-01

    The melanoma cell adhesion molecule defines mesenchymal stromal cells in the human bone marrow that regenerate bone and establish a hematopoietic microenvironment in vivo. The role of the melanoma cell adhesion molecule in primary human mesenchymal stromal cells and the maintenance of hematopoietic stem and progenitor cells during ex vivo culture has not yet been demonstrated. We applied RNA interference or ectopic overexpression of the melanoma cell adhesion molecule in human mesenchymal stromal cells to evaluate the effect of the melanoma cell adhesion molecule on their proliferation and differentiation as well as its influence on co-cultivated hematopoietic stem and progenitor cells. Knockdown and overexpression of the melanoma cell adhesion molecule affected several characteristics of human mesenchymal stromal cells related to osteogenic differentiation, proliferation, and migration. Furthermore, knockdown of the melanoma cell adhesion molecule in human mesenchymal stromal cells stimulated the proliferation of hematopoietic stem and progenitor cells, and strongly reduced the formation of long-term culture-initiating cells. In contrast, melanoma cell adhesion molecule-overexpressing human mesenchymal stromal cells provided a supportive microenvironment for hematopoietic stem and progenitor cells. Expression of the melanoma cell adhesion molecule increased the adhesion of hematopoietic stem and progenitor cells to human mesenchymal stromal cells and their migration beneath the monolayer of human mesenchymal stromal cells. Our results demonstrate that the expression of the melanoma cell adhesion molecule in human mesenchymal stromal cells determines their fate and regulates the maintenance of hematopoietic stem and progenitor cells through direct cell-cell contact.

  14. Corticosterone Inhibits the Proliferation of C6 Glioma Cells via the Translocation of Unphosphorylated Glucocorticoid Receptor.

    PubMed

    Nakatani, Yoshihiko; Amano, Taku; Takeda, Hiroshi

    2016-01-01

    Astroglial cells have been considered to have passive brain function by helping to maintain neurons. However, recent studies have revealed that the dysfunction of such passive functions may be associated with various neuropathological diseases, such as schizophrenia, Alzheimer's disease, amyotrophic lateral sclerosis and major depression. Corticosterone (CORT), which is often referred to as the stress hormone, is a well-known regulator of peripheral immune responses and also shows anti-inflammatory properties in the brain. However, it is still obscure how CORT affects astroglial cell function. In this study, we investigated the effects of CORT on the proliferation and survival of astroglial cells using C6 glioma cells. Under treatment with CORT for 24h, the proliferation of C6 glioma cells decreased in a dose-dependent manner. Moreover, this inhibition was diminised by treatment with mifepristone, a glucocorticoid receptor (GR) antagonist, but not by spironolactone, a mineralocorticoid receptor (MR) antagonist, and was independent of GR phosphorylation and other GR-related intracellular signaling cascades. Furthermore, it was observed that the translocation of GR from the cytosol to the nucleus was promoted by the treatment with CORT. These results indicate that CORT decreases the proliferation of C6 glioma cells by modifying the transcription of a particular gene related to cell proliferation independent of GR phosphorylation.

  15. [Identification of proliferating cells in Taenia solium cysts].

    PubMed

    Orrego-Solano, Miguel Ángel; Cangalaya, Carla; Nash, Theodore E; Guerra-Giraldez, Cristina

    2014-01-01

    Neoblasts are totipotent cells, solely responsible for the proliferation and maturation of tissues in free-living flatworms. Similar cells have been isolated from parasitic flatworms such as Echinococcus. Taenia solium causes human taeniasis (intestinal) and cysticercosis in humans and pigs. Brain infection with larvae (cysts) of T. solium results in neurocysticercosis which is hyperendemic in Peru, and its treatment is associated with serious neurological symptoms. The proliferative capacity and development stages of T. solium have not been described and the neoblasts of this parasite have not been characterized We looked for cell proliferation in T. solium cysts collected from an infected pig, which were identified when replicating and incorporating bromodeoxyuridine nucleotide detected with a monoclonal antibody. A stable cell line of neoblasts would be useful for systematic in vitro studies on drug efficacy and the biology of T. solium.

  16. The Antiaging Gene Klotho Regulates Proliferation and Differentiation of Adipose-Derived Stem Cells

    PubMed Central

    Fan, Jun; Sun, Zhongjie

    2017-01-01

    Klotho was originally discovered as an aging-suppressor gene. The purpose of this study was to investigate whether secreted Klotho (SKL) affects the proliferation and differentiation of adipose-derived stem cells (ADSCs). RT-PCR and Western blot analysis showed that short-form Klotho was expressed in mouse ADSCs. The Klotho gene mutation KL(−/−) significantly decreased proliferation of ADSCs and expression of pluripotent transcription factors (Nanog, Sox-2, and Oct-4) in mice. The adipogenic differentiation of ADSCs was also decreased in KL(−/−) mice. Incubation with Klotho-deficient medium decreased ADSC proliferation, pluripotent transcription factor levels, and adipogenic differentiation, which is similar to what was found in KL(−/−) mice. These results indicate that Klotho deficiency suppresses ADSC proliferation and differentiation. Interestingly, treatment with recombinant SKL protein rescued the Klotho deficiency-induced impairment in ADSC proliferation and adipogenic differentiation. SKL also regulated ADSCs’ differentiation to other cell lineages (osteoblasts, myofibroblasts), indicating that SKL maintains stemness of ADSCs. It is intriguing that overexpression of SKL significantly increased PPAR-γ expression and lipid formation in ADSCs following adipogenic induction, indicating enhanced adipogenic differentiation. Overexpression of SKL inhibited expression of TGFβ1 and its downstream signaling mediator Smad2/3. This study demonstrates, for the first time, that SKL is essential to the maintenance of normal proliferation and differentiation in ADSCs. Klotho regulates adipogenic differentiation in ADSCs, likely via inhibition of TGFβ1 and activation of PPAR-γ. PMID:26865060

  17. Substrate rigidity regulates human T cell activation and proliferation.

    PubMed

    O'Connor, Roddy S; Hao, Xueli; Shen, Keyue; Bashour, Keenan; Akimova, Tatiana; Hancock, Wayne W; Kam, Lance C; Milone, Michael C

    2012-08-01

    Adoptive immunotherapy using cultured T cells holds promise for the treatment of cancer and infectious disease. Ligands immobilized on surfaces fabricated from hard materials such as polystyrene plastic are commonly employed for T cell culture. The mechanical properties of a culture surface can influence the adhesion, proliferation, and differentiation of stem cells and fibroblasts. We therefore explored the impact of culture substrate stiffness on the ex vivo activation and expansion of human T cells. We describe a simple system for the stimulation of the TCR/CD3 complex and the CD28 receptor using substrates with variable rigidity manufactured from poly(dimethylsiloxane), a biocompatible silicone elastomer. We show that softer (Young's Modulus [E] < 100 kPa) substrates stimulate an average 4-fold greater IL-2 production and ex vivo proliferation of human CD4(+) and CD8(+) T cells compared with stiffer substrates (E > 2 MPa). Mixed peripheral blood T cells cultured on the stiffer substrates also demonstrate a trend (nonsignificant) toward a greater proportion of CD62L(neg), effector-differentiated CD4(+) and CD8(+) T cells. Naive CD4(+) T cells expanded on softer substrates yield an average 3-fold greater proportion of IFN-γ-producing Th1-like cells. These results reveal that the rigidity of the substrate used to immobilize T cell stimulatory ligands is an important and previously unrecognized parameter influencing T cell activation, proliferation, and Th differentiation. Substrate rigidity should therefore be a consideration in the development of T cell culture systems as well as when interpreting results of T cell activation based upon solid-phase immobilization of TCR/CD3 and CD28 ligands.

  18. Substrate rigidity regulates human T cell activation and proliferation1

    PubMed Central

    O’Connor, Roddy S.; Hao, Xueli; Shen, Keyue; Bashour, Keenan; Akimova, Tatiana; Hancock, Wayne W.; Kam, Lance; Milone, Michael C.

    2012-01-01

    Adoptive immunotherapy using cultured T cells holds promise for the treatment of cancer and infectious disease. Ligands immobilized on surfaces fabricated from hard materials such as polystyrene plastic are commonly employed for T cell culture. The mechanical properties of a culture surface can influence the adhesion, proliferation, and differentiation of stem cells and fibroblasts. We therefore explored the impact of culture substrate stiffness on the ex vivo activation and expansion of human T cells. We describe a simple system for the stimulation of the TCR/CD3 complex and the CD28 receptor using substrates with variable rigidity manufactured from poly(dimethylsiloxane) (PDMS), a biocompatible silicone elastomer. We show that softer (Young’s Modulus [E] < 100 kPa) substrates stimulate an average 4-fold greater IL-2 production and ex vivo proliferation of human CD4+ and CD8+ T cells compared with stiffer substrates (E >2 MPa). Mixed peripheral blood T cells cultured on the stiffer substrates also demonstrate a trend (non-significant) towards a greater proportion of CD62Lneg, effector-differentiated CD4+ and CD8+ T cells. Naïve CD4+ T cells expanded on softer substrates yield an average 3-fold greater proportion of IFN-γ producing TH1-like cells. These results reveal that the rigidity of the substrate used to immobilize T cell stimulatory ligands is an important and previously unrecognized parameter influencing T cell activation, proliferation and TH differentiation. Substrate rigidity should therefore be a consideration in the development of T cell culture systems as well as when interpreting results of T cell activation based upon solid-phase immobilization of TCR/CD3 and CD28 ligands. PMID:22732590

  19. The effect of temperature on proliferation and differentiation of chicken skeletal muscle satellite cells isolated from different muscle types.

    PubMed

    Harding, Rachel L; Halevy, Orna; Yahav, Shlomo; Velleman, Sandra G

    2016-04-01

    Skeletal muscle satellite cells are a muscle stem cell population that mediate posthatch muscle growth and repair. Satellite cells respond differentially to environmental stimuli based upon their fiber-type of origin. The objective of this study was to determine how temperatures below and above the in vitro control of 38°C affected the proliferation and differentiation of satellite cells isolated from the chicken anaerobic pectoralis major (p. major) or mixed fiber biceps femoris (b.femoris) muscles. The satellite cells isolated from the p. major muscle were more sensitive to both cold and hot temperatures compared to the b.femoris satellite cells during both proliferation and differentiation. The expressions of myogenic regulatory transcription factors were also different between satellite cells from different fiber types. MyoD expression, which partially regulates proliferation, was generally expressed at higher levels in p. major satellite cells compared to the b.femoris satellite cells from 33 to 43°C during proliferation and differentiation. Similarly, myogenin expression, which is required for differentiation, was also expressed at higher levels in p. major satellite cells in response to both cold and hot temperatures during proliferation and differentiation than b. femoris satellite cells. These data demonstrate that satellite cells from the anaerobic p. major muscle are more sensitive than satellite cells from the aerobic b. femoris muscle to both hot and cold thermal stress during myogenic proliferation and differentiation.

  20. Epigenetic regulation of IL-12-dependent T cell proliferation

    PubMed Central

    Schaller, Matthew; Ito, Toshihiro; Allen, Ronald M.; Kroetz, Danielle; Kittan, Nicolai; Ptaschinski, Catherine; Cavassani, Karen; Carson, William F.; Godessart, Nuria; Grembecka, Jolanta; Cierpicki, Tomasz; Dou, Yali; Kunkel, Steven L.

    2015-01-01

    It is well established that the cytokine IL-12 and the transcription factor STAT4, an essential part of the IL-12 signaling pathway, are critical components of the Th1 differentiation process in T cells. In response to pathogenic stimuli, this process causes T cells to proliferate rapidly and secrete high amounts of the cytokine IFN-γ, leading to the Th1 proinflammatory phenotype. However, there are still unknown components of this differentiation pathway. We here demonstrated that the expression of the histone methyltransferase Mll1 is driven by IL-12 signaling through STAT4 in humans and mice and is critical for the proper differentiation of a naïve T cell to a Th1 cell. Once MLL1 is up-regulated by IL-12, it regulates the proliferation of Th1 cells. As evidence of this, we show that Th1 cells from Mll1+/− mice are unable to proliferate rapidly in a Th1 environment in vitro and in vivo. Additionally, upon restimulation with cognate antigen Mll1+/−, T cells do not convert to a Th1 phenotype, as characterized by IFN-γ output. Furthermore, we observed a reduction in IFN-γ production and proliferation in human peripheral blood stimulated with tetanus toxoid by use of a specific inhibitor of the MLL1/menin complex. Together, our results demonstrate that the MLL1 gene plays a previously unrecognized but essential role in Th1 cell biology and furthermore, describes a novel pathway through which Mll1 expression is regulated. PMID:26059830

  1. Inhibition of Pancreatic Cancer Cell Proliferation by LRH-1 Inhibitors

    DTIC Science & Technology

    2013-09-01

    AD_________________ Award Number: W81XWH-12-1-0396 TITLE: INHIBITION OF PANCREATIC CANCER CELL...DATES COVERED 15September2012–14September2013 4. TITLE AND SUBTITLE INHIBITION OF PANCREATIC CANCER CELL PROLIFERATION BY LRH-1 INHIBITORS 5a...of pancreatic cancer is devastating, with mortality rates nearing its incidence rates. To date, there are no effective targeted anti-pancreatic

  2. PTPN2 attenuates T-cell lymphopenia-induced proliferation

    NASA Astrophysics Data System (ADS)

    Wiede, Florian; La Gruta, Nicole L.; Tiganis, Tony

    2014-01-01

    When the peripheral T-cell pool is depleted, T cells undergo homoeostatic expansion. This expansion is reliant on the recognition of self-antigens and/or cytokines, in particular interleukin-7. The T cell-intrinsic mechanisms that prevent excessive homoeostatic T-cell responses and consequent overt autoreactivity remain poorly defined. Here we show that protein tyrosine phosphatase N2 (PTPN2) is elevated in naive T cells leaving the thymus to restrict homoeostatic T-cell proliferation and prevent excess responses to self-antigens in the periphery. PTPN2-deficient CD8+ T cells undergo rapid lymphopenia-induced proliferation (LIP) when transferred into lymphopenic hosts and acquire the characteristics of antigen-experienced effector T cells. The enhanced LIP is attributed to elevated T-cell receptor-dependent, but not interleukin-7-dependent responses, results in a skewed T-cell receptor repertoire and the development of autoimmunity. Our results identify a major mechanism by which homoeostatic T-cell responses are tuned to prevent the development of autoimmune and inflammatory disorders.

  3. Pancreatic β-Cell Proliferation in Obesity12

    PubMed Central

    Linnemann, Amelia K.; Baan, Mieke; Davis, Dawn Belt

    2014-01-01

    Because obesity rates have increased dramatically over the past 3 decades, type 2 diabetes has become increasingly prevalent as well. Type 2 diabetes is associated with decreased pancreatic β-cell mass and function, resulting in inadequate insulin production. Conversely, in nondiabetic obesity, an expansion in β-cell mass occurs to provide sufficient insulin and to prevent hyperglycemia. This expansion is at least in part due to β-cell proliferation. This review focuses on the mechanisms regulating obesity-induced β-cell proliferation in humans and mice. Many factors have potential roles in the regulation of obesity-driven β-cell proliferation, including nutrients, insulin, incretins, hepatocyte growth factor, and recently identified liver-derived secreted factors. Much is still unknown about the regulation of β-cell replication, especially in humans. The extracellular signals that activate proliferative pathways in obesity, the relative importance of each of these pathways, and the extent of cross-talk between these pathways are important areas of future study. PMID:24829474

  4. Aeroallergen challenge promotes dendritic cell proliferation in the airways.

    PubMed

    Veres, Tibor Z; Voedisch, Sabrina; Spies, Emma; Valtonen, Joona; Prenzler, Frauke; Braun, Armin

    2013-02-01

    Aeroallergen provocation induces the rapid accumulation of CD11c(+)MHC class II (MHC II)(+) dendritic cells (DCs) in the lungs, which is driven by an increased recruitment of blood-derived DC precursors. Recent data show, however, that well-differentiated DCs proliferate in situ in various tissues. This may also contribute to their allergen-induced expansion; therefore, we studied DC proliferation in the airways of mice in the steady state and after local aeroallergen provocation. Confocal whole-mount microscopy was used to visualize proliferating DCs in different microanatomical compartments of the lung. We demonstrate that in the steady state, CD11c(+)MHC II(+) DCs proliferate in both the epithelial and subepithelial layers of the airway mucosa as well as in the lung parenchyma. A 1-h pulse of the nucleotide 5-ethynyl-2'-deoxyuridine was sufficient to label 5% of DCs in both layers of the airway mucosa. On the level of whole-lung tissue, 3-5% of both CD11b(+) and CD11b(-) DC populations and 0.3% of CD11c(+)MHC II(low) lung macrophages incorporated 5-ethynyl-2'-deoxyuridine. Aeroallergen provocation caused a 3-fold increase in the frequency of locally proliferating DCs in the airway mucosa. This increase in mucosal DC proliferation was later followed by an elevation in the number of DCs. The recruitment of monocyte-derived inflammatory DCs contributed to the increasing number of DCs in the lung parenchyma, but not in the airway mucosa. We conclude that local proliferation significantly contributes to airway DC homeostasis in the steady state and that it is the major mechanism underlying the expansion of the mucosal epithelial/subepithelial DC network in allergic inflammation.

  5. Involvement of calreticulin in cell proliferation, invasion and differentiation in diallyl disulfide-treated HL-60 cells.

    PubMed

    Yi, Lan; Shan, Jian; Chen, Xin; Li, Guoqing; Li, Linwei; Tan, Hui; Su, Qi

    2016-09-01

    Diallyl disulfide (DADS) has shown potential as a therapeutic agent in various cancers. Previously, calreticulin (CRT) was found to be downregulated in differentiated HL-60 cells treated with DADS. The present study investigated the role of CRT proteins in DADS-induced proliferation, invasion and differentiation in HL-60 cells. The present study demonstrated that DADS treatment significantly changed the morphology of HL-60 cells and caused the significant time-dependent downregulation of CRT. Small interfering RNA (siRNA)-mediated knockdown of CRT expression significantly inhibited proliferation, decreased invasion ability, increased the expression of cluster of differentiation (CD)11b and reduced the expression of CD33 in DADS-treated HL-60 cells. DADS also significantly affected cell proliferation, invasion and differentiation in CRT-overexpressed HL-60 cells. Nitroblue tetrazolium (NBT) reduction assays showed decreased NBT reduction activity in the CRT overexpression group and increased NBT reduction in the CRT siRNA group. Following treatment with DADS, the NBT reduction abilities in all groups were increased. In conclusion, the present study clearly demonstrates the downregulation of CRT during DADS-induced differentiation in HL-60 cells and indicates that CRT is involved in cell proliferation, invasion and differentiation in DADS-treated HL-60 cells.

  6. Effects of SOX2 on Proliferation, Migration and Adhesion of Human Dental Pulp Stem Cells.

    PubMed

    Liu, Pengfei; Cai, Jinglei; Dong, Delu; Chen, Yaoyu; Liu, Xiaobo; Wang, Yi; Zhou, Yulai

    2015-01-01

    As a key factor for cell pluripotent and self-renewing phenotypes, SOX2 has attracted scientists' attention gradually in recent years. However, its exact effects in dental pulp stem cells (DPSCs) are still unclear. In this study, we mainly investigated whether SOX2 could affect some biological functions of DPSCs. DPSCs were isolated from the dental pulp of human impacted third molar. SOX2 overexpressing DPSCs (DPSCs-SOX2) were established through retroviral infection. The effect of SOX2 on cell proliferation, migration and adhesion ability was evaluated with CCK-8, trans-well system and fibronectin-induced cell attachment experiment respectively. Whole genome expression of DPSCs-SOX2 was analyzed with RNA microarray. Furthermore, a rescue experiment was performed with SOX2-siRNA in DPSC-SOX2 to confirm the effect of SOX2 overexpression in DPSCs. We found that SOX2 overexpression could result in the enhancement of cell proliferation, migration, and adhesion in DPSCs obviously. RNA microarray analysis indicated that some key genes in the signal pathways associated with cell cycle, migration and adhesion were upregulated in different degree, and the results were further confirmed with qPCR and western-blot. Finally, DPSC-SOX2 transfected with SOX2-siRNA showed a decrease of cell proliferation, migration and adhesion ability, which further confirmed the biological effect of SOX2 in human DPSCs. This study indicated that SOX2 could improve the cell proliferation, migration and adhesion ability of DPSCs through regulating gene expression about cell cycle, migration and adhesion, and provided a novel strategy to develop seed cells with strong proliferation, migration and adhesion ability for tissue engineering.

  7. TGF-{beta}2 inhibits AKT activation and FGF-2-induced corneal endothelial cell proliferation

    SciTech Connect

    Lu Jiawei; Lu Zhenyu; Reinach, Peter

    2006-11-01

    The corneal endothelial cells form a boundary layer between anterior chamber and cornea. This single cell layer is important to maintain cornea transparency by eliciting net fluid transport into the anterior chamber. Injuries of the corneal endothelial layer in humans lead to corneal swelling and translucence. This hindrance is thought to be due to limited proliferative capacity of the endothelial layer. Fibroblast growth factor 2 (FGF-2) and transforming growth factor-beta 2 (TGF-{beta}2) are both found in aqueous humor, and these two cytokines promote and inhibit cell growth, respectively. The intracellular signaling mechanisms by which TGF-{beta}2 suppresses the mitogenic response to FGF-2, however, remain unclear. We have addressed this question by investigating potential crosstalk between FGF-2-induced and TGF-{beta}2-regulated intracellular signaling events in cultured bovine corneal endothelial (BCE) cells. We found that TGF-{beta}2 and FGF-2 oppositely affect BCE cell proliferation and TGF-{beta}2 can override the stimulating effects of FGF-2 by increasing COX-2 expression in these cells. Consistent with these findings, overexpression of COX-2 significantly reduced FGF-2-induced cell proliferation whereas a COX-2 specific inhibitor NS398 reversed the effect of TGF-{beta}2 on FGF-2-induced cell proliferation. The COX-2 product prostaglandin E2 (PGE-2) blocks FGF-2-induced cell proliferation. Whereas FGF-2 stimulates cell proliferation by activating the AKT pathway, TGF-{beta}2 and PGE-2 both inhibit this pathway. In accordance with the effect of PGE-2, cAMP also inhibits FGF-2-induced AKT activation. These findings suggest that the mitogenic response to FGF-2 in vivo in the corneal endothelial layer may be inhibited by TGF-{beta}2-induced suppression of the PI3-kinase/AKT signaling pathway.

  8. Lack of effect of a granulocyte proliferation inhibitor or their committed precursor cells.

    PubMed

    Lord, B I; Testa, N G; Wright, E G; Banerjee, R K

    1977-05-01

    Using the agar culture technique, we have measured the effect of granulocyte extracts GCE (and of erythrocyte-RCE and lymph node extracts-LNE) on the growth and proliferation of the committed granulocytic precursor cells, CFU-C. In addition we have determined their effects on the proliferation of the developing colony cells and on the ultimate cell production in the colonies. The results show that GCE has no effect on the growth or proliferative activity on the CFU-C. It does, however, reduce both the autoradiographic labelling indices of the developing colony cells and the net colony cellularities, acting as a cell cycle modulator. These are effects specific to the GCE since at the dose levels used, neither RCE nor LNE affected these measurements.

  9. Maternal Forced Swimming Reduces Cell Proliferation in the Postnatal Dentate Gyrus of Mouse Offspring

    PubMed Central

    Wasinski, Frederick; Estrela, Gabriel R.; Arakaki, Aline M.; Bader, Michael; Alenina, Natalia; Klempin, Friederike; Araújo, Ronaldo C.

    2016-01-01

    Physical exercise positively affects the metabolism and induces proliferation of precursor cells in the adult brain. Maternal exercise likewise provokes adaptations early in the offspring. Using a high-intensity swimming protocol that comprises forced swim training before and during pregnancy, we determined the effect of maternal swimming on the mouse offspring's neurogenesis. Our data demonstrate decreased proliferation in sublayers of the postnatal dentate gyrus in offspring of swimming mother at postnatal day (P) 8 accompanied with decreased survival of newly generated cells 4 weeks later. The reduction in cell numbers was predominantly seen in the hilus and molecular layer. At P35, the reduced amount of cells was also reflected by a decrease in the population of newly generated immature and mature neurons of the granule cell layer. Our data suggest that forced maternal swimming at high-intensity has a negative effect on the neurogenic niche development in postnatal offspring. PMID:27621701

  10. The Retinoblastoma pathway regulates stem cell proliferation in freshwater planarians.

    PubMed

    Zhu, Shu Jun; Pearson, Bret J

    2013-01-15

    Freshwater planarians are flatworms of the Lophotrochozoan superphylum and are well known for their regenerative abilities, which rely on a large population of pluripotent adult stem cells. However, the mechanisms by which planarians maintain a precise population of adult stem cells while balancing proliferation and cell death, remain to be elucidated. Here we have identified, characterized, and functionally tested the core Retinoblastoma (Rb) pathway components in planarian adult stem cell biology. The Rb pathway is an ancient and conserved mechanism of proliferation control from plants to animals and is composed of three core components: an Rb protein, and a transcription factor heterodimer of E2F and DP proteins. Although the planarian genome contains all components of the Rb pathway, we found that they have undergone gene loss from the ancestral state, similar to other species in their phylum. The single Rb homolog (Smed-Rb) was highly expressed in planarian stem cells and was required for stem cell maintenance, similar to the Rb-homologs p107 and p130 in vertebrates. We show that planarians and their phylum have undergone the most severe reduction in E2F genes observed thus far, and the single remaining E2F was predicted to be a repressive-type E2F (Smed-E2F4-1). Knockdown of either Smed-E2F4-1 or its dimerization partner Dp (Smed-Dp) by RNAi resulted in temporary hyper-proliferation. Finally, we showed that known Rb-interacting genes in other systems, histone deacetylase 1 and cyclinD (Smed-HDAC1; Smed-cycD), were similar to Rb in expression and phenotypes when knocked down by RNAi, suggesting that these established interactions with Rb may also be conserved in planarians. Together, these results showed that planarians use the conserved components of the Rb tumor suppressor pathway to control proliferation and cell survival.

  11. LPA Induces Colon Cancer Cell Proliferation through a Cooperation between the ROCK and STAT-3 Pathways

    PubMed Central

    Leve, Fernanda; Peres-Moreira, Rubem J.; Binato, Renata; Abdelhay, Eliana; Morgado-Díaz, José A.

    2015-01-01

    Lysophosphatidic acid (LPA) plays a critical role in the proliferation and migration of colon cancer cells; however, the downstream signaling events underlying these processes remain poorly characterized. The aim of this study was to investigate the signaling pathways triggered by LPA to regulate the mechanisms involved in the progression of colorectal cancer (CRC). We have used three cell line models of CRC, and initially analyzed the expression profile of LPA receptors (LPAR). Then, we treated the cells with LPA and events related to their tumorigenic potential, such as migration, invasion, anchorage-independent growth, proliferation as well as apoptosis and cell cycle were evaluated. We used the Chip array technique to analyze the global gene expression profiling that occurs after LPA treatment, and we identified cell signaling pathways related to the cell cycle. The inhibition of these pathways verified the conclusions of the transcriptomic analysis. We found that the cell lines expressed LPAR1, -2 and -3 in a differential manner and that 10 μM LPA did not affect cell migration, invasion and anchorage-independent growth, but it did induce proliferation and cell cycle progression in HCT-116 cells. Although LPA in this concentration did not induce transcriptional activity of β-catenin, it promoted the activation of Rho and STAT-3. Moreover, ROCK and STAT-3 inhibitors prevented LPA-induced proliferation, but ROCK inhibition did not prevent STAT-3 activation. Finally, we observed that LPA regulates the expression of genes related to the cell cycle and that the combined inhibition of ROCK and STAT-3 prevented cell cycle progression and increased the LPA-induced expression of cyclins E1, A2 and B1 to a greater degree than either inhibitor alone. Overall, these results demonstrate that LPA increases the proliferative potential of colon adenocarcinoma HCT-116 cells through a mechanism involving cooperation between the Rho-ROCK and STAT3 pathways involved in cell

  12. LPA Induces Colon Cancer Cell Proliferation through a Cooperation between the ROCK and STAT-3 Pathways.

    PubMed

    Leve, Fernanda; Peres-Moreira, Rubem J; Binato, Renata; Abdelhay, Eliana; Morgado-Díaz, José A

    2015-01-01

    Lysophosphatidic acid (LPA) plays a critical role in the proliferation and migration of colon cancer cells; however, the downstream signaling events underlying these processes remain poorly characterized. The aim of this study was to investigate the signaling pathways triggered by LPA to regulate the mechanisms involved in the progression of colorectal cancer (CRC). We have used three cell line models of CRC, and initially analyzed the expression profile of LPA receptors (LPAR). Then, we treated the cells with LPA and events related to their tumorigenic potential, such as migration, invasion, anchorage-independent growth, proliferation as well as apoptosis and cell cycle were evaluated. We used the Chip array technique to analyze the global gene expression profiling that occurs after LPA treatment, and we identified cell signaling pathways related to the cell cycle. The inhibition of these pathways verified the conclusions of the transcriptomic analysis. We found that the cell lines expressed LPAR1, -2 and -3 in a differential manner and that 10 μM LPA did not affect cell migration, invasion and anchorage-independent growth, but it did induce proliferation and cell cycle progression in HCT-116 cells. Although LPA in this concentration did not induce transcriptional activity of β-catenin, it promoted the activation of Rho and STAT-3. Moreover, ROCK and STAT-3 inhibitors prevented LPA-induced proliferation, but ROCK inhibition did not prevent STAT-3 activation. Finally, we observed that LPA regulates the expression of genes related to the cell cycle and that the combined inhibition of ROCK and STAT-3 prevented cell cycle progression and increased the LPA-induced expression of cyclins E1, A2 and B1 to a greater degree than either inhibitor alone. Overall, these results demonstrate that LPA increases the proliferative potential of colon adenocarcinoma HCT-116 cells through a mechanism involving cooperation between the Rho-ROCK and STAT3 pathways involved in cell

  13. Seizures induce proliferation and dispersion of doublecortin-positive hippocampal progenitor cells.

    PubMed

    Jessberger, Sebastian; Römer, Benedikt; Babu, Harish; Kempermann, Gerd

    2005-12-01

    One neuropathological hallmark of temporal lobe epilepsy is granule cell dispersion, a widening of the hippocampal granule cell layer (GCL) with abnormally positioned excitatory neurons. The finding that seizure activity also induces adult hippocampal neurogenesis was taken largely as indicative of a regenerative attempt, not as part of the pathology. The aim of our study was to characterize a potential relationship between granule cell dispersion and seizure-induced neurogenesis. Kainic acid (KA)-induced seizures in mice led to increased cell proliferation and new neurons persisted for months after the seizures. We show that the proliferative stimulus did not affect nestin-expressing early precursor cells that primarily respond to physiologic mitogenic stimuli, but stimulated the division of late type-3 progenitor cells, which express doublecortin (DCX), a protein associated with cell migration. This delayed proliferation presumably interfered with migration, leading to a significant dispersion of DCX-positive progenitors and early postmitotic neurons within the dentate gyrus granule cell layer. We propose that initial seizures induce ectopic precursor cell proliferation resulting in the dispersion of immature neurons within the adult granule cell layer. Thus, seizure-generated neurons might contribute to the disease process of epilepsy.

  14. Human β-Cell Proliferation and Intracellular Signaling: Part 3

    PubMed Central

    Hussain, Mehboob A.; García-Ocaña, Adolfo; Vasavada, Rupangi C.; Bhushan, Anil; Bernal-Mizrachi, Ernesto

    2015-01-01

    This is the third in a series of Perspectives on intracellular signaling pathways coupled to proliferation in pancreatic β-cells. We contrast the large knowledge base in rodent β-cells with the more limited human database. With the increasing incidence of type 1 diabetes and the recognition that type 2 diabetes is also due in part to a deficiency of functioning β-cells, there is great urgency to identify therapeutic approaches to expand human β-cell numbers. Therapeutic approaches might include stem cell differentiation, transdifferentiation, or expansion of cadaver islets or residual endogenous β-cells. In these Perspectives, we focus on β-cell proliferation. Past Perspectives reviewed fundamental cell cycle regulation and its upstream regulation by insulin/IGF signaling via phosphatidylinositol-3 kinase/mammalian target of rapamycin signaling, glucose, glycogen synthase kinase-3 and liver kinase B1, protein kinase Cζ, calcium-calcineurin–nuclear factor of activated T cells, epidermal growth factor/platelet-derived growth factor family members, Wnt/β-catenin, leptin, and estrogen and progesterone. Here, we emphasize Janus kinase/signal transducers and activators of transcription, Ras/Raf/extracellular signal–related kinase, cadherins and integrins, G-protein–coupled receptors, and transforming growth factor β signaling. We hope these three Perspectives will serve to introduce these pathways to new researchers and will encourage additional investigators to focus on understanding how to harness key intracellular signaling pathways for therapeutic human β-cell regeneration for diabetes. PMID:25999530

  15. Axl receptor tyrosine kinase is a novel target of apigenin for the inhibition of cell proliferation.

    PubMed

    Kim, Kyung-Chan; Choi, Eun-Ha; Lee, Chuhee

    2014-08-01

    The Axl receptor tyrosine kinase (RTK), along with Tyro 3 and Mer, belongs to the TAM subfamily that promotes survival, stimulates proliferation and/or inhibits apoptosis. In various types of human cancer, including breast, lung and prostate cancer, Axl expression is increased and correlates with an advanced clinical stage. In this study, we examined whether apigenin has an effect on Axl expression, which in turn can affect cell proliferation. The treatment of the non‑small cell lung cancer (NSCLC) cells, A549 and H460, with apigenin decreased Axl mRNA and protein expression in a dose‑dependent manner. Axl promoter activity was also inhibited by apigenin, indicating that apigenin suppressed Axl expression at the transcriptional level. Upon treatment with apigenin, the viability of both the A549 and H460 cells was gradually decreased and the anti-proliferative effects were further confirmed by the dose‑dependent decrease in the clonogenic ability of the apigenin‑treated cells. Subsequently, we found that the viability and clonogenic ability of the cells treated with apigenin was less or more affected by transfection of the cells with a Axl-expressing plasmid or Axl targeting siRNA, compared to transfection with the empty vector or control siRNA, respectively. In addition, apigenin increased the expression of p21, a cyclin-dependent kinase inhibitor, but reduced the expression of X-linked inhibitor of apoptosis protein (XIAP). These cell cycle arrest and pro-apoptotic effects of apigenin were also attenuated or augmented by the up- or downregulation of Axl expression, respectively, which suggests that Axl is a novel target of apigenin through which it exerts its inhibitory effects on cell proliferation. Taken together, our data indicate that apigenin downregulates Axl expression, which subsequently results in the inhibition of NSCLC cell proliferation through the increase and decrease of p21 and XIAP expression, respectively.

  16. Focally regulated endothelial proliferation and cell death in human synovium.

    PubMed Central

    Walsh, D. A.; Wade, M.; Mapp, P. I.; Blake, D. R.

    1998-01-01

    Angiogenesis and vascular insufficiency each may support the chronic synovial inflammation of rheumatoid arthritis. We have shown by quantitative immunohistochemistry and terminal uridyl deoxynucleotide nick end labeling that endothelial proliferation and cell death indices were each increased in synovia from patients with rheumatoid arthritis compared with osteoarthritic and noninflamed controls, whereas endothelial fractional areas did not differ significantly among disease groups. Markers of proliferation were associated with foci immunoreactive for vascular endothelial growth factor and integrin alpha(v)beta3, whereas cell death was observed in foci in which immunoreactivities for these factors were weak or absent. No association was found with thrombospondin immunoreactivity. The balance between angiogenesis and vascular regression in rheumatoid synovitis may be determined by the focal expression of angiogenic and endothelial survival factors. Increased endothelial cell turnover may contribute to microvascular dysfunction and thereby facilitate persistent synovitis. Images Figure 1 Figure 3 Figure 4 PMID:9502411

  17. Ethanol inhibits human bone cell proliferation and function in vitro

    SciTech Connect

    Friday, K.E.; Howard, G.A. )

    1991-06-01

    The direct effects of ethanol on human bone cell proliferation and function were studied in vitro. Normal human osteoblasts from trabecular bone chips were prepared by collagenase digestion. Exposure of these osteoblasts to ethanol in concentrations of 0.05% to 1% for 22 hours induced a dose-dependent reduction in bone cell DNA synthesis as assessed by incorporation of 3H-thymidine. After 72 hours of ethanol exposure in concentrations of 0.01% to 1%, protein synthesis as measured by 3H-proline incorporation into trichbroacetic acid (TCA)-precipitable material was reduced in a dose-dependent manner. Human bone cell protein concentrations and alkaline phosphatase total activity were significantly reduced after exposure to 1% ethanol for 72 hours, but not with lower concentrations of ethanol. This reduction in osteoblast proliferation and activity may partially explain the development of osteopenia in humans consuming excessive amounts of ethanol.

  18. Petasites japonicus Stimulates the Proliferation of Mouse Spermatogonial Stem Cells

    PubMed Central

    Kim, Yong-Hee; Lee, Dong Gu; Kim, Bang-Jin; Kim, Ki-Jung; Kim, Byung-Gak; Oh, Myeong-Geun; Han, Chan Kyu; Lee, Sanghyun; Ryu, Buom-Yong

    2015-01-01

    Oriental natural plants have been used as medical herbs for the treatment of various diseases for over 2,000 years. In this study, we evaluated the effect of several natural plants on the preservation of male fertility by assessing the ability of plant extracts to stimulate spermatogonial stem cell (SSC) proliferation by using a serum-free culture method. In vitro assays showed that Petasites japonicus extracts, especially the butanol fraction, have a significant effect on germ cells proliferation including SSCs. The activity of SSCs cultured in the presence of the Petasites japonicus butanol fraction was confirmed by normal colony formation and spermatogenesis following germ cell transplantation of the treated SSCs. Our findings could lead to the discovery of novel factors that activate SSCs and could be useful for the development of technologies for the prevention of male infertility. PMID:26207817

  19. Control of cell proliferation by microRNAs in plants.

    PubMed

    Rodriguez, Ramiro E; Schommer, Carla; Palatnik, Javier F

    2016-12-01

    Plants have the ability to generate different and new organs throughout their life cycle. Organ growth is mostly determined by the combinatory effects of cell proliferation and cell expansion. Still, organ size and shape are adjusted constantly by environmental conditions and developmental timing. The plasticity of plant development is further illustrated by the diverse organ forms found in nature. MicroRNAs (miRNAs) are known to control key biological processes in plants. In this review, we will discuss recent findings showing the participation of miRNA networks in the regulation of cell proliferation and organ growth. It has become clear that miRNA networks play both integrative and specific roles in the control of organ development in Arabidopsis thaliana. Furthermore, recent work in different species demonstrated a broad role for miR396 in the control of organ size, and that specific tuning of the miR396 network can improve crop yield.

  20. Toxic effects of sodium fluoride on cell proliferation and apoptosis of Leydig cells from young mice.

    PubMed

    Song, Guo hua; Wang, Rui Li; Chen, Zhao Yang; Zhang, Bin; Wang, Hai Long; Liu, Mao Lin; Gao, Ji Ping; Yan, Xiao Yan

    2014-09-01

    The biological effects of fluoride on human health are often extensive, either beneficial or detrimental. Among the various effects of fluoride exposure in different organs, the reproductive tract is particularly susceptible to disruption by fluoride at a sufficient concentration. It has attracted much attention to the effect of sodium fluoride on male fertility, gestational female, and offspring. Herein, we applied a widespread natural compound sodium fluoride (NaF) and investigated the effects of acute NaF exposure on Leydig cells, including their proliferation, apoptosis, and signal pathway changes. Our results demonstrated that high dosage of NaF could inhibit cell proliferation by stress-induced apoptosis, which was confirmed by cellular and molecular evidences. We found that fluoride exposure affected the expression levels of stress response factors, signal transduction components, and apoptosis-related proteins, including caspase-3/caspase-9, B-cell lymphoma 2 (Bcl-2), and Bax. This study suggests that the complex effects of fluoride on Leydig cells are closely related to its dosage.

  1. Quantitative analysis of cell proliferation by a dye dilution assay: Application to cell lines and cocultures.

    PubMed

    Chung, Soobin; Kim, Seol-Hee; Seo, Yuri; Kim, Sook-Kyung; Lee, Ji Youn

    2017-04-04

    Cell proliferation represents one of the most fundamental processes in biological systems, thus the quantitative analysis of cell proliferation is important in many biological applications such as drug screening, production of biologics, and assessment of cytotoxicity. Conventional proliferation assays mainly quantify cell number based on a calibration curve of a homogeneous cell population, and therefore are not applicable for the analysis of cocultured cells. Moreover, these assays measure cell proliferation indirectly, based on cellular metabolic activity or DNA content. To overcome these shortcomings, a dye dilution assay employing fluorescent cell tracking dyes that are retained within cells was applied and was diluted proportionally by subsequent cell divisions. Here, it was demonstrated that this assay could be implemented to quantitatively analyze the cell proliferation of different types of cell lines, and to concurrently analyze the proliferation of two types of cell lines in coculture by utilizing cell tracking dyes with different spectral characteristics. The mean division time estimated by the dye dilution assay is compared with the population doubling time obtained from conventional methods and values from literature. Additionally, dye transfer between cocultured cells was investigated and it was found that it is a characteristic of the cells rather than a characteristic of the dye. It was suggested that this method can be easily combined with other flow cytometric analyses of cellular properties, providing valuable information on cell status under diverse conditions. © 2017 International Society for Advancement of Cytometry.

  2. Metabolic profiling of hematopoietic stem and progenitor cells during proliferation and differentiation into red blood cells.

    PubMed

    Daud, Hasbullah; Browne, Susan; Al-Majmaie, Rasoul; Murphy, William; Al-Rubeai, Mohamed

    2016-01-25

    An understanding of the metabolic profile of cell proliferation and differentiation should support the optimization of culture conditions for hematopoietic stem and progenitor cell (HSPC) proliferation, differentiation, and maturation into red blood cells. We have evaluated the key metabolic parameters during each phase of HSPC culture for red blood cell production in serum-supplemented (SS) and serum-free (SF) conditions. A simultaneous decrease in growth rate, total protein content, cell size, and the percentage of cells in the S/G2 phase of cell cycle, as well as an increase in the percentage of cells with a CD71(-)/GpA(+) surface marker profile, indicates HSPC differentiation into red blood cells. Compared with proliferating HSPCs, differentiating HSPCs showed significantly lower glucose and glutamine consumption rates, lactate and ammonia production rates, and amino acid consumption and production rates in both SS and SF conditions. Furthermore, extracellular acidification was associated with late proliferation phase, suggesting a reduced cellular metabolic rate during the transition from proliferation to differentiation. Under both SS and SF conditions, cells demonstrated a high metabolic rate with a mixed metabolism of both glycolysis and oxidative phosphorylation (OXPHOS) in early and late proliferation, an increased dependence on OXPHOS activity during differentiation, and a shift to glycolytic metabolism only during maturation phase. These changes indicate that cell metabolism may have an important impact on the ability of HSPCs to proliferate and differentiate into red blood cells.

  3. Alpha2 adrenoceptors regulate proliferation of human intestinal epithelial cells

    PubMed Central

    Schaak, S; Cussac, D; Cayla, C; Devedjian, J; Guyot, R; Paris, H; Denis, C

    2000-01-01

    BACKGROUND AND AIMS—Previous studies on rodents have suggested that catecholamines stimulate proliferation of the intestinal epithelium through activation of α2 adrenoceptors located on crypt cells. The occurrence of this effect awaits demonstration in humans and the molecular mechanisms involved have not yet been elucidated. Here, we examined the effect of α2 agonists on a clone of Caco2 cells expressing the human α2A adrenoceptor.
METHODS—Cells were transfected with a bicistronic plasmid containing the α2C10 and neomycin phosphotransferase genes. G418 resistant clones were assayed for receptor expression using radioligand binding. Receptor functionality was assessed by testing its ability to couple Gi proteins and to inhibit cAMP production. Mitogen activated protein kinase (MAPK) phosphorylation was followed by western blot, and cell proliferation was estimated by measuring protein and DNA content.
RESULTS—Permanent transfection of Caco2 cells allowed us to obtain a clone (Caco2-3B) expressing α2A adrenoceptors at a density similar to that found in normal human intestinal epithelium. Caco2-3B retained morphological features and brush border enzyme expression characteristic of enterocytic differentiation. The receptor was coupled to Gi2/Gi3 proteins and its stimulation caused marked diminution of forskolin induced cAMP production. Treatment of Caco2-3B with UK14304 (α2 agonist) induced a rapid increase in the phosphorylation state of MAPK, extracellular regulated protein kinase 1 (Erk1), and 2 (Erk2). This event was totally abolished in pertussis toxin treated cells and in the presence of kinase inhibitors (genistein or PD98059). It was unaffected by protein kinase C downregulation but correlated with a transient increase in Shc tyrosine phosphorylation. Finally, sustained exposure of Caco2-3B to UK14304 resulted in modest but significant acceleration of cell proliferation. None of these effects was observed in the parental cell line Caco2.

  4. Nuclear lamins and oxidative stress in cell proliferation and longevity.

    PubMed

    Shimi, Takeshi; Goldman, Robert D

    2014-01-01

    In mammalian cells, the nuclear lamina is composed of a complex fibrillar network associated with the inner membrane of the nuclear envelope. The lamina provides mechanical support for the nucleus and functions as the major determinant of its size and shape. At its innermost aspect it associates with peripheral components of chromatin and thereby contributes to the organization of interphase chromosomes. The A- and B-type lamins are the major structural components of the lamina, and numerous mutations in the A-type lamin gene have been shown to cause many types of human diseases collectively known as the laminopathies. These mutations have also been shown to cause a disruption in the normal interactions between the A and B lamin networks. The impact of these mutations on nuclear functions is related to the roles of lamins in regulating various essential processes including DNA synthesis and damage repair, transcription and the regulation of genes involved in the response to oxidative stress. The major cause of oxidative stress is the production of reactive oxygen species (ROS), which is critically important for cell proliferation and longevity. Moderate increases in ROS act to initiate signaling pathways involved in cell proliferation and differentiation, whereas excessive increases in ROS cause oxidative stress, which in turn induces cell death and/or senescence. In this review, we cover current findings about the role of lamins in regulating cell proliferation and longevity through oxidative stress responses and ROS signaling pathways. We also speculate on the involvement of lamins in tumor cell proliferation through the control of ROS metabolism.

  5. Liver cyst cytokines promote endothelial cell proliferation and development.

    PubMed

    Brodsky, Kelley S; McWilliams, Ryan R; Amura, Claudia R; Barry, Nicholas P; Doctor, R Brian

    2009-10-01

    Autosomal dominant polycystic kidney (ADPKD) is highly prevalent genetic disease. Liver cyst disease is the most common extrarenal manifestation in ADPKD and accounts for up to 10% of ADPKD morbidity and mortality. The clinical features of ADPKD liver disease arise from dramatic increases in liver cyst volumes. To identify mechanisms that promote liver cyst growth, the present study characterized the degree of vascularization of liver cyst walls and determined that cyst-specific cytokines and growth factors can drive endothelial cell proliferation and development. Microscopic techniques demonstrated liver cyst walls are well vascularized. A comparative analysis found the vascular density in free liver cyst walls was greater in mice than in humans. Treatment of human micro-vascular endothelial cells (HMEC-1) with human liver cyst fluid (huLCF) induced a rapid increase in vascular endothelium growth factor receptor 2 (VEGFR2) phosphorylation that persisted for 45-60 min and was blocked by 20 microM SU5416, a VEGFR tyrosine kinase inhibitor. Similarly, huLCF treatment of HMEC-1 cells induced an increase in the cell proliferation rate (131 +/- 6% of control levels; P > 0.05) and the degree of vascular development ('tube' diameter assay: 92 +/- 14 microm for huLCF vs. 12 +/- 7 microm for vehicle); P > 0.05). Both cell proliferation and vascular development were sensitive to SU5416. These studies indicate that factors secreted by liver cyst epithelia can activate VEGF signaling pathways and induce endothelial cell proliferation and differentiation. The present studies suggest that targeting VEGFR2-dependent angiogenesis may be an effective therapeutic strategy in blocking ADPKD liver cyst vascularization and growth.

  6. Effects of hypergravity on adipose-derived stem cell morphology, mechanical property and proliferation

    SciTech Connect

    Tavakolinejad, Alireza; Rabbani, Mohsen; Janmaleki, Mohsen

    2015-08-21

    Alteration in specific inertial conditions can lead to changes in morphology, proliferation, mechanical properties and cytoskeleton of cells. In this report, the effects of hypergravity on morphology of Adipose-Derived Stem Cells (ADSCs) are indicated. ADSCs were repeatedly exposed to discontinuous hypergravity conditions of 10 g, 20 g, 40 g and 60 g by utilizing centrifuge (three times of 20 min exposure, with an interval of 40 min at 1 g). Cell morphology in terms of length, width and cell elongation index and cytoskeleton of actin filaments and microtubules were analyzed by image processing. Consistent changes observed in cell elongation index as morphological change. Moreover, cell proliferation was assessed and mechanical properties of cells in case of elastic modulus of cells were evaluated by Atomic Force Microscopy. Increase in proliferation and decrease in elastic modulus of cells are further results of this study. Staining ADSC was done to show changes in cytoskeleton of the cells associated to hypergravity condition specifically in microfilament and microtubule components. After exposing to hypergravity, significant changes were observed in microfilaments and microtubule density as components of cytoskeleton. It was concluded that there could be a relationship between changes in morphology and MFs as the main component of the cells. - Highlights: • Hypergravity (10 g, 20 g, 40 g and 60 g) affects on adipose derived stem cells (ADSCs). • ADSCs after exposure to the hypergravity are more slender. • The height of ADSCs increases in all test groups comparing their control group. • Hypergravity decreases ADSCs modulus of elasticity and cell actin fiber content. • Hypergravity enhances proliferation rate of ADSCs.

  7. Pannexin 1 regulates postnatal neural stem and progenitor cell proliferation

    PubMed Central

    2012-01-01

    Background Pannexin 1 forms ion and metabolite permeable hexameric channels and is abundantly expressed in the brain. After discovering pannexin 1 expression in postnatal neural stem and progenitor cells we sought to elucidate its functional role in neuronal development. Results We detected pannexin 1 in neural stem and progenitor cells in vitro and in vivo. We manipulated pannexin 1 expression and activity in Neuro2a neuroblastoma cells and primary postnatal neurosphere cultures to demonstrate that pannexin 1 regulates neural stem and progenitor cell proliferation likely through the release of adenosine triphosphate (ATP). Conclusions Permeable to ATP, a potent autocrine/paracine signaling metabolite, pannexin 1 channels are ideally suited to influence the behavior of neural stem and progenitor cells. Here we demonstrate they play a robust role in the regulation of neural stem and progenitor cell proliferation. Endogenous postnatal neural stem and progenitor cells are crucial for normal brain health, and their numbers decline with age. Furthermore, these special cells are highly responsive to neurological injury and disease, and are gaining attention as putative targets for brain repair. Therefore, understanding the fundamental role of pannexin 1 channels in neural stem and progenitor cells is of critical importance for brain health and disease. PMID:22458943

  8. Selective cytotoxicity of benzyl isothiocyanate in the proliferating fibroblastoid cells.

    PubMed

    Miyoshi, Noriyuki; Uchida, Koji; Osawa, Toshihiko; Nakamura, Yoshimasa

    2007-02-01

    In the present study, experiments using presynchronization culture cells demonstrated that benzyl ITC (BITC), previously isolated from a tropical papaya fruit extract, induced the cytotoxic effect preferentially in the proliferating human colon CCD-18Co cells to the quiescent ones. Quiescent CCD-18Co cells were virtually unaffected by BITC and marginal cytotoxicity was observed at 15 microM. We observed that BITC dramatically induced the p53 phosphorylation and stabilization only in the quiescent (G(0)/G(1) phase-arrested) cells, but not significantly in the proliferating human colon CCD-18Co cells when compared with quiescent ones. We also observed ataxia telangiectasia-mutated (ATM) phosphorylation in the quiescent cells. The BITC-induced p53 phosphorylation was counteracted by caffeine treatment, implying the involvement of an ATM/ataxia telangiectasia and Rad3-related kinase signaling pathway. Moreover, downregulation of p53 by a siRNA resulted in the enhancement of susceptibility to undergo apoptosis by BITC. We also showed here that depletion of p53 abrogated G(0)/G(1) arrest accompanied by the declined expression of p21(waf1/cip1) and p27(kip1) in CCD-18Co cells. In conclusion, we identified p53 as a potential negative regulator of the apoptosis induction by BITC in the normal colon CCD-18Co cells through the inhibition of cell-cycle progression at the G(0)/G(1) phase.

  9. Effects of gastric vagotomy on visceral cell proliferation induced by ventromedial hypothalamic lesions: role of vagal hyperactivity.

    PubMed

    Kintaka, Yuri; Osaka, Toshimasa; Suzuki, Yoko; Hashiguchi, Takeo; Niijima, Akira; Kageyama, Haruaki; Fumiko, Takenoya; Shioda, Seiji; Inoue, Shuji

    2009-07-01

    In rats, ventromedial hypothalamic (VMH) lesions induce cell proliferation in the visceral organs (stomach, small intestine, liver, and pancreas) due to hyperactivity of the vagus nerve. To investigate the effects of selective gastric vagotomy on VMH lesion-induced cell proliferation and secretion of gastric acid, we assessed the mitotic index (the number of proliferating cell nuclear antigen (PCNA)-immunopositive cells per 1,000 cells in the gastric mucosal cell layer) and measured the volume of secreted basal gastric acid. Furthermore, to explore whether or not ethanol-induced acute gastric mucosal lesions (AGML) lead to ulcer formation in VMH-lesioned rats, we assessed the ulcer index of both sham-operated and VMH-lesioned rats after administration of ethanol. VMH lesions resulted in an increased mitotic index and thickness of the gastric mucosal cell layer and gave rise to the hypersecretion of gastric acid. Selective gastric vagotomy restored these parameters to normal without affecting cell proliferation in other visceral organs. Ethanol-induced AGML caused ulcers in sham VMH-lesioned rats, whereas VMH-lesioned rats were less likely to exhibit such ulcers. These results suggest that VMH lesion-induced vagally mediated cell proliferation in the visceral organs is associated with hyperfunction in these organs, and VMH lesion-induced resistance to ethanol may be due to thickening of the gastric mucosal cell layer resulting from cell proliferation in the gastric mucosa-this in turn is due to hyperactivity of the vagus nerve.

  10. Magnesium regulates neural stem cell proliferation in the mouse hippocampus by altering mitochondrial function.

    PubMed

    Jia, Shanshan; Mou, Chengzhi; Ma, Yihe; Han, Ruijie; Li, Xue

    2016-04-01

    In the adult brain, neural stem cells from the subgranular zone (SGZ) of the hippocampus and the subventricular zone (SVZ) of the cortex progress through the following five developmental stages: radial glia-like cells, neural progenitor cells, neuroblasts, immature neurons, and mature neurons. These developmental stages are linked to both neuronal microenvironments and energy metabolism. Neurogenesis is restricted and has been demonstrated to arise from tissue microenvironments. We determined that magnesium, a key nutrient in cellular energy metabolism, affects neural stem cell (NSC) proliferation in cells derived from the embryonic hippocampus by influencing mitochondrial function. Densities of proliferating cells and NSCs both showed their highest values at 0.8 mM [Mg(2+) ]o , whereas lower proliferation rates were observed at 0.4 and 1.4 mM [Mg(2+) ]o . The numbers and sizes of the neurospheres reached the maximum at 0.8 mM [Mg(2+) ]o and were weaker under both low (0.4 mM) and high (1.4 mM) concentrations of magnesium. In vitro experimental evidence demonstrates that extracellular magnesium regulates the number of cultured hippocampal NSCs, affecting both magnesium homeostasis and mitochondrial function. Our findings indicate that the effect of [Mg(2+) ]o on NSC proliferation may lie downstream of alterations in mitochondrial function because mitochondrial membrane potential was highest in the NSCs in the moderate [Mg(2+) ]o (0.8 mM) group and lower in both the low (0.4 mM) and high (1.4 mM) [Mg(2+) ]o groups. Overall, these findings demonstrate a new function for magnesium in the brain in the regulation of hippocampal neural stem cells: affecting their cellular energy metabolism.

  11. Role of aquaporins in cell proliferation: What else beyond water permeability?

    PubMed

    Galán-Cobo, Ana; Ramírez-Lorca, Reposo; Echevarría, Miriam

    2016-01-01

    In addition to the extensive data demonstrating the importance of mammalian AQPs for the movement of water and some small solutes across the cell membrane, there is now a growing body of evidence indicating the involvement of these proteins in numerous cellular processes seemingly unrelated, at least some of them in a direct way, to their canonical function of water permeation. Here, we have presented a broad range of evidence demonstrating that these proteins have a role in cell proliferation by various different mechanisms, namely, by allowing fast cell volume regulation during cell division; by affecting progression of cell cycle and helping maintain the balance between proliferation and apoptosis, and by crosstalk with other cell membrane proteins or transcription factors that, in turn, modulate progression of the cell cycle or regulate biosynthesis pathways of cell structural components. In the end, however, after discussing all these data that strongly support a role for AQPs in the cell proliferation process, it remains impossible to conclude that all these other functions attributed to AQPs occur completely independently of their water permeability, and there is a need for new experiments designed specifically to address this interesting issue.

  12. Role of aquaporins in cell proliferation: What else beyond water permeability?

    PubMed Central

    Galán-Cobo, Ana; Ramírez-Lorca, Reposo; Echevarría, Miriam

    2016-01-01

    abstract In addition to the extensive data demonstrating the importance of mammalian AQPs for the movement of water and some small solutes across the cell membrane, there is now a growing body of evidence indicating the involvement of these proteins in numerous cellular processes seemingly unrelated, at least some of them in a direct way, to their canonical function of water permeation. Here, we have presented a broad range of evidence demonstrating that these proteins have a role in cell proliferation by various different mechanisms, namely, by allowing fast cell volume regulation during cell division; by affecting progression of cell cycle and helping maintain the balance between proliferation and apoptosis, and by crosstalk with other cell membrane proteins or transcription factors that, in turn, modulate progression of the cell cycle or regulate biosynthesis pathways of cell structural components. In the end, however, after discussing all these data that strongly support a role for AQPs in the cell proliferation process, it remains impossible to conclude that all these other functions attributed to AQPs occur completely independently of their water permeability, and there is a need for new experiments designed specifically to address this interesting issue. PMID:26752515

  13. Enzymatically crosslinked gelatin hydrogel promotes the proliferation of adipose tissue-derived stromal cells

    PubMed Central

    Ren, Xiaomei; Long, Haiyan; Qian, Hong; Ma, Kunlong

    2016-01-01

    Gelatin hydrogel crosslinked by microbial transglutaminase (mTG) exhibits excellent performance in cell adhesion, proliferation, and differentiation. We examined the gelation time and gel strength of gelatin/mTG hydrogels in various proportions to investigate their physical properties and tested their degradation performances in vitro. Cell morphology and viability of adipose tissue-derived stromal cells (ADSCs) cultured on the 2D gel surface or in 3D hydrogel encapsulation were evaluated by immunofluorescence staining. Cell proliferation was tested via Alamar Blue assay. To investigate the hydrogel effect on cell differentiation, the cardiac-specific gene expression levelsof Nkx2.5, Myh6, Gja1, and Mef2c in encapsulated ADSCs with or without cardiac induction medium were detected by real-time RT-PCR. Cell release from the encapsulated status and cell migration in a 3D hydrogel model were assessed in vitro. Results show that the gelatin/mTG hydrogels are not cytotoxic and that their mechanical properties are adjustable. Hydrogel degradation is related to gel concentration and the resident cells. Cell growth morphology and proliferative capability in both 2D and 3D cultures were mainly affected by gel concentration. PCR result shows that hydrogel modulus together with induction medium affects the cardiac differentiation of ADSCs. The cell migration experiment and subcutaneous implantation show that the hydrogels are suitable for cell delivery. PMID:27703850

  14. Enzymatically crosslinked gelatin hydrogel promotes the proliferation of adipose tissue-derived stromal cells.

    PubMed

    Yang, Gang; Xiao, Zhenghua; Ren, Xiaomei; Long, Haiyan; Qian, Hong; Ma, Kunlong; Guo, Yingqiang

    2016-01-01

    Gelatin hydrogel crosslinked by microbial transglutaminase (mTG) exhibits excellent performance in cell adhesion, proliferation, and differentiation. We examined the gelation time and gel strength of gelatin/mTG hydrogels in various proportions to investigate their physical properties and tested their degradation performances in vitro. Cell morphology and viability of adipose tissue-derived stromal cells (ADSCs) cultured on the 2D gel surface or in 3D hydrogel encapsulation were evaluated by immunofluorescence staining. Cell proliferation was tested via Alamar Blue assay. To investigate the hydrogel effect on cell differentiation, the cardiac-specific gene expression levelsof Nkx2.5, Myh6, Gja1, and Mef2c in encapsulated ADSCs with or without cardiac induction medium were detected by real-time RT-PCR. Cell release from the encapsulated status and cell migration in a 3D hydrogel model were assessed in vitro. Results show that the gelatin/mTG hydrogels are not cytotoxic and that their mechanical properties are adjustable. Hydrogel degradation is related to gel concentration and the resident cells. Cell growth morphology and proliferative capability in both 2D and 3D cultures were mainly affected by gel concentration. PCR result shows that hydrogel modulus together with induction medium affects the cardiac differentiation of ADSCs. The cell migration experiment and subcutaneous implantation show that the hydrogels are suitable for cell delivery.

  15. Inhibition of proliferation of retinal vascular endothelial cells more effectively than choroidal vascular endothelial cell proliferation by bevacizumab

    PubMed Central

    Mynampati, Bharani Krishna; Sambhav, Kumar; Grover, Sandeep; Chalam, Kakarla V.

    2017-01-01

    AIM To evaluate the differential inhibitory effects of bevacizumab on cell proliferation of vascular endothelial growth factor (VEGF)-stimulated choroidal vascular endothelial cells (CVECs) and retinal vascular endothelial cells (RVECs) in vitro. METHODS VEGF (400 ng/mL) enriched CVECs and RVECs were treated with escalating doses of bevacizumab (0.1, 0.5, 1, 1.5 and 2 mg/mL). Cell proliferation changes were analyzed with WST-1 assay and trypan blue exclusion assay at 48, 72h and 1wk. Morphological changes were recorded with bright field microscopy. RESULTS VEGF enriched RVECs showed significantly more decline of cell viability than CVECs after bevacizumab treatment. One week after treatment, RVEC cell proliferation decreased by 29.7%, 37.5%, 52.8%, 35.9% and 45.6% at 0.1, 0.5, 1.0, 1.5 and 2 mg/mL bevacizumab respectively compared to CVEC proliferation decrease of 4.1%, 7.7%, 2.4%, 4.1% and 17.7% (P<0.05) by WST-1 assay. Trypan blue exclusion assay also revealed similar decrease in RVEC proliferation of 20%, 60%, 73.3%, 80% and 93.3% compared to CVEC proliferation decrease of 4%, 12%, 22.9%, 16.7% and 22.2% respectively (P<0.05). The maximum differential effect between the two cell types was observed at bevacizumab doses of 1.0 and 1.5 mg/mL at all time points. RVECs were 22 fold more sensitive (P<0.01) compared to CVECs (52.8% vs 2.4%) at concentration of 1.0 mg/mL, and 8.7 fold more at 1.5 mg/mL (35.9% vs 4.1%) 1wk after treatment (P<0.05 respectively). CONCLUSION VEGF-enriched RVECs are more susceptible to bevacizumab inhibition than CVECs at clinically used dosage of 1.25 mg and this differential sensitivity between two cell types should be taken into consideration in dosage selection. PMID:28149771

  16. Upregulated microRNA-224 promotes ovarian cancer cell proliferation by targeting KLLN.

    PubMed

    Hu, Ke; Liang, Meng

    2017-02-01

    Human epithelial ovarian cancer is a complex disease, with low 5-yr survival rate largely due to the terminal stage at diagnosis in most patients. MicroRNAs play critical roles during epithelial ovarian cancer progression in vivo and have also been shown to regulate characteristic of ovarian cancer cell line in vitro. Alterative microRNA-224 (microRNA-224) expression affects human epithelial ovarian cancer cell survival, apoptosis, and metastasis. However, people know little about the effects of microRNA-224 on epithelial ovarian cancer cell proliferation. In the current study, we found that the microRNA-224 expression level of human syngeneic epithelial ovarian cancer cells HO8910 (low metastatic ability) was lower than that of HO8910PM (high metastatic ability). Furthermore, microRNA-224 was confirmed to target KLLN in HO8910 and HO8910PM. The known KLLN downstream target cyclin A was regulated by microRNA-224 in HO8910 and HO8910PM. In addition, overexpression of microRNA-224 enhanced the proliferation abilities of HO8910 and knockdown of microRNA-224 suppressed the proliferation abilities of HO8910PM by KLLN-cyclin A pathway. Our results provide new data about microRNAs and their targets involved in proliferation of epithelial ovarian cancer cells by modulating the downstream signaling.

  17. Angiotensin Converting Enzyme Regulates Cell Proliferation and Migration

    PubMed Central

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

    2016-01-01

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

  18. Simulated Hypergravity Alters Vascular Smooth Muscle Cell Proliferation and Motility

    NASA Technical Reports Server (NTRS)

    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.

  19. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inhibits human ovarian cancer cell proliferation

    PubMed Central

    Li, Yan; Wang, Kai; Jiang, Yi-Zhou; Chang, Xin-Wen; Dai, Cai-Feng

    2017-01-01

    Purpose The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, mediates a broad spectrum of biological processes, including ovarian growth and ovulation. Recently, we found that an endogenous AhR ligand (ITE) can inhibit ovarian cancer proliferation and migration via the AhR. Here, we tested whether 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, an exogenous AhR ligand) may exert similar anti-ovarian cancer activities using human ovarian cancer and non-cancerous human ovarian surface epithelial cells. Methods Two human ovarian cancer cell lines (SKOV-3 and OVCAR-3) and one human ovarian surface epithelial cell line (IOSE-385) were used. Cell proliferation and migration activities were determined using crystal violet and FluoroBlok insert system assays, respectively. AhR protein expression was assessed by Western blotting. Expression of cytochrome P450, family 1, member A1 (CYP1A1) and member B1 (CYP1B1) mRNA was assessed by qPCR. Small interfering RNAs (siRNAs) were used to knock down AhR expression. Results We found that TCDD dose-dependently suppressed OVCAR-3 cell proliferation, with a maximum effect (~70 % reduction) at 100 nM. However, TCDD did not affect SKOV-3 and IOSE-385 cell proliferation and migration. The estimated IC50 of TCDD for inhibiting OVCAR-3 cell proliferation was 4.6 nM. At 10 nM, TCDD time-dependently decreased AhR protein levels, while it significantly increased CYP1A1 and CYP1B1 mRNA levels in SKOV-3, OVCAR-3 and IOSE-385 cells, indicating activation of AhR signaling. siRNA-mediated AhR knockdown readily blocked TCDD-mediated suppression of OVCAR-3 cell proliferation. Conclusion Our data indicate that TCDD can suppress human ovarian cancer cell proliferation via the AhR signaling pathway and that TCDD exhibits an anti-proliferative activity in at least a subset of human ovarian cancer cells. PMID:25404385

  20. Cell proliferation during the early stages of human eye development.

    PubMed

    Bozanić, Darka; Saraga-Babić, Mirna

    2004-08-01

    The distribution as well as the ultrastructural and biochemical characteristics of proliferating cells in the human eye were investigated in five conceptuses of 5-9 postovulatory weeks, using morphological techniques and Ki-67 immunostaining. The Ki-67 nuclear protein was used as a proliferation marker because of its expression in all phases of the cell cycle except the resting phase (G0). The labelling indices of Ki-67-positive cells were analysed by means of the Kruskal-Wallis ANOVA test and the Wilcoxon matched-pairs test. In the 5th week, mitotic cells were the most numerous between the two layers of the optic cup, the optic cup and stalk, and between the lens pit and the surface ectoderm. During the 6th week, cells were observed in the lens epithelium covering the whole cavity of the lens vesicle as well as in the neuroblast zone and the pigmented epithelium of the retina. At later stages (7th-9th weeks), Ki-67-positive cells were restricted to the anterior lens epithelium, the outer neuroblast zone, and the pigmented retina. Throughout all stages examined, mitotic figures were found lying exclusively adjacent to the intraretinal space. Early in the lens pit, they were confined to the free epithelial surface, and later were facing the cavity of the lens vesicle. The proliferative activity was the most intensive in the 6th week, whereas it decreased significantly in the later stages. Additionally, when proliferative activities were compared, the peripheral retina appeared to be less mature than the central before the 9th week. In the earliest analysed stage, cell proliferation might be associated with the sculpturing of the optic cup and stalk, the cornea, and the lens. In the 6th week, the most intensive proliferation seems to be involved not only in the further morphogenesis of the optic cup and the lens vesicle but also in the retinal neurogenesis. At later stages, the decreased proliferation might participate in the neurogenesis of the outer neuroblast zone

  1. Overexpression of prothymosin alpha accelerates proliferation and retards differentiation in HL-60 cells.

    PubMed

    Rodríguez, P; Viñuela, J E; Alvarez-Fernández, L; Buceta, M; Vidal, A; Domínguez, F; Gómez-Márquez, J

    1998-05-01

    Prothymosin alpha (ProTalpha) is an acidic nuclear protein the expression of which is related to the proliferation and differentiation processes in mammalian cells. In the present study we have stably transfected HL-60 cells, a biological system that allows the study of both proliferation and differentiation, with recombinant vectors encoding sense and antisense ProTalpha mRNA. In the HL-60 cell clones overexpressing ProTalpha we observed an acceleration in the growth rate, whereas expression of the antisense orientation showed the opposite effect. Moreover, cell-cycle analysis demonstrated that the G1-phase was shortened in the cells expressing the sense construct. Before studying how ProTalpha affects differentiation, we showed that the down-regulation of ProTalpha gene during differentiation occurs in all mammalian cell lines (HL-60, K562, U937, MEL C88, N2A and PC12) analysed. The biological effect evoked by the induction of the ProTalpha sense vector was the retardation of cell differentiation, although expression of the antisense construct showed no effect on differentiation. In conclusion, our findings provide evidence that ProTalpha is directly implicated in cellular proliferation and that the maintenance of high levels of ProTalpha inside HL-60 cells is incompatible with their ability to differentiate.

  2. Overexpression of prothymosin alpha accelerates proliferation and retards differentiation in HL-60 cells.

    PubMed Central

    Rodríguez, P; Viñuela, J E; Alvarez-Fernández, L; Buceta, M; Vidal, A; Domínguez, F; Gómez-Márquez, J

    1998-01-01

    Prothymosin alpha (ProTalpha) is an acidic nuclear protein the expression of which is related to the proliferation and differentiation processes in mammalian cells. In the present study we have stably transfected HL-60 cells, a biological system that allows the study of both proliferation and differentiation, with recombinant vectors encoding sense and antisense ProTalpha mRNA. In the HL-60 cell clones overexpressing ProTalpha we observed an acceleration in the growth rate, whereas expression of the antisense orientation showed the opposite effect. Moreover, cell-cycle analysis demonstrated that the G1-phase was shortened in the cells expressing the sense construct. Before studying how ProTalpha affects differentiation, we showed that the down-regulation of ProTalpha gene during differentiation occurs in all mammalian cell lines (HL-60, K562, U937, MEL C88, N2A and PC12) analysed. The biological effect evoked by the induction of the ProTalpha sense vector was the retardation of cell differentiation, although expression of the antisense construct showed no effect on differentiation. In conclusion, our findings provide evidence that ProTalpha is directly implicated in cellular proliferation and that the maintenance of high levels of ProTalpha inside HL-60 cells is incompatible with their ability to differentiate. PMID:9560301

  3. Modification of granulocytopoietic cell proliferation by granulocyte extracts.

    PubMed

    Lord, B I

    1975-07-31

    Saline extracts of mature granulocytes have been partially purified by an ultrafiltration technique. The fraction in the 500-2000 daltons molecular weight range was retained and tested in a variety of experimental systems. Comparable fractions of erythrocyte and lymphocyte extracts were used for control purposes. Measurement of the structuredness of the cytoplasmic matrix (SCM) of cells is shown to be a very sensitive measure of the effects of the extract. Specific and reversible increases in SCM of proliferating granulocytic cell populations indicate changes compatible with reduced proliferation and these are confirmed by autoradiographic observations following tritiated thymidine labelling. Repeated labelling experiments to obtain the rate of flow of cells through the cycle gave a mean cell cycle time of 15 hrs in the controls but in animals treated with the granulocyte extract this was increased to about 30 hrs. The duration of DNA synthesis was increased slightly but there was no effect on G2 as measured by the stathmokinetic index method. Cell production in developing spleen colonies was reduced by repeated doses of the extract over a period of 4 days. Approximately two cell doublings were lost during this period due to the prolonged cell cycle.

  4. Aging and immortality in a cell proliferation model.

    PubMed

    Antal, T; Blagoev, K B; Trugman, S A; Redner, S

    2007-10-07

    We investigate a model of cell division in which the length of telomeres within a cell regulates its proliferative potential. At each division, telomeres undergo a systematic length decrease as well as a superimposed fluctuation due to exchange of telomere DNA between the two daughter cells. A cell becomes senescent when one or more of its telomeres become shorter than a critical length. We map this telomere dynamics onto a biased branching-diffusion process with an absorbing boundary condition whenever any telomere reaches the critical length. Using first-passage ideas, we find a phase transition between finite lifetime and immortality (infinite proliferation) of the cell population as a function of the influence of telomere shortening, fluctuations, and cell division.

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

    SciTech Connect

    Hwang, Chae Young; Lee, Seung-Min; Park, Sung Sup; Kwon, Ki-Sun

    2012-08-17

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

  6. Nerve growth factor modulate proliferation of cultured rabbit corneal endothelial cells and epithelial cells.

    PubMed

    Li, Xinyu; Li, Zhongguo; Qiu, Liangxiu; Zhao, Changsong; Hu, Zhulin

    2005-01-01

    In order to investigate the effect of nerve growth factor (NGF) on the proliferation of rabbit corneal endothelial cells and epithelial cells, the in vitro cultured rabbit corneal endothelial cells and epithelial cells were treated with different concentrations of NGF. MTT assay was used to examine the clonal growth and proliferation of the cells by determining the absorbency values at 570 nm. The results showed that NGF with three concentrations ranging from 5 U/mL to 500 U/mL enhanced the proliferation of rabbit corneal endothelial cells in a concentration-dependent manner. 50 U/mL and 500 U/mL NGF got more increase of proliferation than that of 5 U/mL NGF did. Meanwhile, 50 U/mL and 500 U/mL NGF could promote the proliferation of the rabbit corneal epithelial cells significantly in a concentration-dependent manner. However, 5 U/mL NGF did not enhance the proliferation of epithelial cells. It was suggested that exogenous NGF can stimulate the proliferation of both rabbit corneal endothelial and epithelial cells, but the extent of modulation is different.

  7. Differential effects of MTSS1 on invasion and proliferation in subtypes of non-small cell lung cancer cells.

    PubMed

    Ling, Dong-Jin; Chen, Zhong-Shu; Liao, Qian-De; Feng, Jian-Xiong; Zhang, Xue-Yu; Yin, Ta-Yao

    2016-08-01

    Non-small cell lung cancer (NSCLC) accounts for >80% of all cases of lung cancer and can be divided into lung adenocarcinoma (LAC), large-cell carcinoma (LCC), and squamous cell carcinoma (SCC). Accumulating evidence suggests that MTSS1, which is a newly discovered protein associated with tumor progression and metastasis, may have differential roles in cancer malignancy. As it has been demonstrated that MTSS1 is overexpressed in NSCLC and may be an independent prognostic factor in patients with SCC, the present study explored the differential roles of MTSS1 in the invasion and proliferation of different subtypes of NSCLC. Stable overexpression and knockdown of MTSS1 was performed in human NSCLC H920 (LAC), H1581 (LCC) and SW900 cell lines (SCC), and western blot, cell invasion, proliferation and FAK activity analyses were used to investigate the effects. Overexpression of MTSS1 enhanced the invasion and proliferation abilities of H920 and H1581 cells, and these effects were abolished by treatment with selective FAK inhibitor 14, which did not affect the expression of MTSS1. Notably, overexpression of MTSS1 inhibited invasion and proliferation in SW900 cells, and this effect was enhanced by the selective FAK inhibitor. Knockdown of MTSS1 decreased the invasion and proliferation abilities of H920 and H1581 cells, whereas knockdown increased invasion and proliferation in SW900 cells. Furthermore, while overexpression of MTSS1 induced FAK phosphorylation and activity in H920 and H1581 cells, MTSS1 overexpression inhibited FAK phosphorylation/activity in SW900 cells. Knockdown of MTSS1 decreased FAK phosphorylation/activity in H920 and H1581 cells, whereas knockdown increased these processes in SW900 cells. To the best of our knowledge, the present study was the first to demonstrate that MTSS1 has differential roles in various subtypes of NSCLC, acting via a FAK-dependent mechanism. The results indicated that MTSS1 may enhance invasion and proliferation in LAC and LCC

  8. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    PubMed Central

    Bruno, Stefania; Grange, Cristina; Tapparo, Marta; Pasquino, Chiara; Romagnoli, Renato; Dametto, Ennia; Amoroso, Antonio; Tetta, Ciro; Camussi, Giovanni

    2016-01-01

    Human liver stem cells (HLSCs) are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs), and dendritic cells (DCs) in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell contact and dependent on the release of prostaglandin E2 (PGE2) and on indoleamine 2,3-dioxygenase activity. When compared with mesenchymal stromal cells (MSCs), HLSCs were more efficient in inhibiting T-cell proliferation. At variance with MSCs, HLSCs did not elicit NK degranulation. Moreover, HLSCs inhibited NK degranulation against K562, a NK-sensitive target, by a mechanism dependent on HLA-G release. When tested on DC generation from monocytes, HLSCs were found to impair DC differentiation and DCs ability to induce T-cell proliferation through PGE2. This study shows that HLSCs have immunomodulatory properties similar to MSCs, but, at variance with MSCs, they do not elicit a NK response. PMID:27127520

  9. Regulation of human natural killer cell migration and proliferation by the exodus subfamily of CC chemokines.

    PubMed

    Robertson, M J; Williams, B T; Christopherson, K; Brahmi, Z; Hromas, R

    2000-01-10

    Natural killer (NK) cells play an important role in innate and adaptive immune responses to obligate intracellular pathogens. Nevertheless, the regulation of NK cell trafficking and migration to inflammatory sites is poorly understood. Exodus-1/MIP-3alpha/LARC, Exodus-2/6Ckine/SLC, and Exodus-3/MIP-3beta/ELC/CKbeta-11 are CC chemokines that share a unique aspartate-cysteine-cysteine-leucine motif near their amino terminus and preferentially stimulate the migration of T lymphocytes. The effects of Exodus chemokines on human NK cells were examined. Exodus-1, -2, and -3 did not induce detectable chemotaxis of resting peripheral blood NK cells. In contrast, Exodus-2 and -3 stimulated migration of polyclonal activated peripheral blood NK cells in a dose-dependent fashion. Exodus-2 and -3 also induced dose-dependent chemotaxis of NKL, an IL-2-dependent human NK cell line. Results of modified checkerboard assays indicate that migration of NKL cells in response to Exodus-2 and -3 represents true chemotaxis and not simply chemokinesis. Exodus-1, -2, and -3 did not induce NK cell proliferation in the absence of other stimuli. Nevertheless, Exodus-2 and -3 significantly augmented IL-2-induced proliferation of normal human CD56(dim) NK cells. In contrast, Exodus-1, -2, and -3 did not affect the cytolytic activity of resting or activated peripheral blood NK cells. Expression of message for CCR7, a shared receptor for Exodus-2 and -3, was detected in activated polyclonal NK cells and NKL cells but not resting NK cells. Taken together, these results indicate that Exodus-2 and -3 can participate in the recruitment and proliferation of activated NK cells. Exodus-2 and -3 may regulate interactions between T cells and NK cells that are crucial for the generation of optimal immune responses.

  10. Oxytocin and oxytocin receptors in cancer cells and proliferation.

    PubMed

    Cassoni, P; Sapino, A; Marrocco, T; Chini, B; Bussolati, G

    2004-04-01

    The hypothalamic nonapeptide oxytocin plays a crucial role in many reproductive and behavioural functions. However, in recent years, an additional new role for oxytocin has been identified in neoplastic pathology. In tumours, oxytocin acts as a growth regulator, through the activation of a specific G-coupled transmembrane receptor, the oxytocin receptor. In vitro, oxytocin inhibits proliferation of neoplastic cells of either epithelial (mammary and endometrial), nervous or bone origin, all expressing oxytocin receptor. Furthermore, an oxytocin growth-inhibiting effect was also tested and confirmed in vivo in mouse and rat mammary carcinomas. In neoplastic cells derived from two additional oxytocin target tissues, trophoblast and endothelium, oxytocin was found to promote cell proliferation, an effect opposite to that previously described in all other neoplastic oxytocin-responsive cells. The signal transduction pathways coupled to the biological effects of oxytocin are different in oxytocin growth-inhibited or growth-stimulated cells, and may depend on the membrane localization of the oxytocin receptor itself. The inhibitory effect of oxytocin is apparently mediated by activation of the cAMP-protein kinase A pathway, a nonconventional oxytocin signalling pathway, whereas the mitogenic effect is coupled to the increase of intracellular [Ca(2+)] and tyrosine phosphorylation, 'classical' oxytocin transducers. Moreover, the oxytocin receptor localization in lipid rafts enriched in caveolin-1 turns the inhibition of cell growth into a proliferative response, eliciting different epidermal growth factor receptor/mitogen-activated protein kinase activation patterns. This unexpected role of oxytocin (and oxytocin analogues) in regulating cell proliferation, as well as the widespread expression of oxytocin receptors in neoplastic tissues of different origin, opens up new perspectives on the biological role of the oxytocin-oxytocin receptor system in cancer.

  11. Cell proliferation and plant development under novel altered gravity environments.

    PubMed

    Herranz, R; Medina, F J

    2014-01-01

    Gravity is a key factor for life on Earth. It is the only environmental factor that has remained constant throughout evolution, and plants use it to modulate important physiological activities; gravity removal or alteration produces substantial changes in essential functions. For root gravitropism, gravity is sensed in specialised cells, which are capable of detecting magnitudes of the g vector lower than 10(-3) . Then, the mechanosignal is transduced to upper zones of the root, resulting in changes in the lateral distribution of auxin and in the rate of auxin polar transport. Gravity alteration has consequences for cell growth and proliferation rates in root meristems, which are the basis of the developmental programme of a plant, in which regulation via auxin is involved. The effect is disruption of meristematic competence, i.e. the strict coordination between cell proliferation and growth, which characterises meristematic cells. This effect can be related to changes in the transport and distribution of auxin throughout the root. However, similar effects of gravity alteration have been found in plant cell cultures in vitro, in which neither specialised structures for gravity sensing and signal transduction, nor apparent gravitropism have been described. We postulate that gravity resistance, a general mechanism of cellular origin for developing rigid structures in plants capable of resisting the gravity force, could also be responsible for the changes in cell growth and proliferation parameters detected in non-specialised cells. The mechanisms of gravitropism and graviresistance are complementary, the first being mostly sensitive to the direction of the gravity vector, and the second to its magnitude. At a global molecular level, the consequence of gravity alteration is that the genome should be finely tuned to counteract a type of stress that plants have never encountered before throughout evolution. Multigene families and redundant genes present an advantage in

  12. Arginine consumption by the intestinal parasite Giardia intestinalis reduces proliferation of intestinal epithelial cells.

    PubMed

    Stadelmann, Britta; Merino, María C; Persson, Lo; Svärd, Staffan G

    2012-01-01

    In the field of infectious diseases the multifaceted amino acid arginine has reached special attention as substrate for the hosts production of the antimicrobial agent nitric oxide (NO). A variety of infectious organisms interfere with this part of the host immune response by reducing the availability of arginine. This prompted us to further investigate additional roles of arginine during pathogen infections. As a model we used the intestinal parasite Giardia intestinalis that actively consumes arginine as main energy source and secretes an arginine-consuming enzyme, arginine deiminase (ADI). Reduced intestinal epithelial cell (IEC) proliferation is a common theme during bacterial and viral intestinal infections, but it has never been connected to arginine-consumption. Our specific question was thereby, whether the arginine-consumption by Giardia leads to reduced IEC proliferation, in addition to NO reduction. In vitro cultivation of human IEC lines in arginine-free or arginine/citrulline-complemented medium, as well as in interaction with different G. intestinalis isolates, were used to study effects on host cell replication by MTT assay. IEC proliferation was further analyzed by DNA content analysis, polyamine measurements and expressional analysis of cell cycle regulatory genes. IEC proliferation was reduced upon arginine-withdrawal and also in an arginine-dependent manner upon interaction with G. intestinalis or addition of Giardia ADI. We show that arginine-withdrawal by intestinal pathogens leads to a halt in the cell cycle in IECs through reduced polyamine levels and upregulated cell cycle inhibitory genes. This is of importance with regards to intestinal tissue homeostasis that is affected through reduced cell proliferation. Thus, the slower epithelial cell turnover helps the pathogen to maintain a more stable niche for colonization. This study also shows why supplementation therapy of diarrhea patients with arginine/citrulline is helpful and that

  13. Identification of glucocorticoid-regulated genes that control cell proliferation during murine respiratory development

    PubMed Central

    Bird, Anthony D; Tan, Kheng H; Olsson, P Fredrik; Zieba, Malgorzata; Flecknoe, Sharon J; Liddicoat, Douglas R; Mollard, Richard; Hooper, Stuart B; Cole, Timothy J

    2007-01-01

    Glucocorticoids play a vital role in fetal respiratory development and act via the intracellular glucocorticoid receptor (GR) to regulate transcription of key target genes. GR-null mice die at birth due to respiratory dysfunction associated with hypercellularity and atelectasis. To identify events associated with this lung phenotype we examined perinatal cellular proliferation rates and apoptotic indices. We demonstrate that compared to wild-type controls, day 18.5 postcoitum (p.c.) GR-null mouse lungs display significantly increased cell proliferation rates (1.8-fold P < 0.05) and no change in apoptosis. To examine underlying molecular mechanisms, we compared whole genome expression profiles by microarray analysis at 18.5 days p.c. Pathways relating to cell proliferation, division and cell cycle were significantly down-regulated while pathways relating to carbohydrate metabolism, kinase activities and immune responses were significantly up-regulated. Differential levels of gene expression were verified by quantitative-RT-PCR and/or Northern analysis. Key regulators of proliferation differentially expressed in the lung of 18.5 p.c. GR-null lungs included p21CIP1 (decreased 2.9-fold, P < 0.05), a negative regulator of the cell cycle, and Mdk (increased 6.0-fold, P < 0.05), a lung growth factor. The more under-expressed genes in 18.5 p.c. GR-null lungs included Chi3l3 (11-fold, P < 0.05), a macrophage inflammatory response gene and Ela1 (9.4-fold, P < 0.05), an extracellular matrix remodeling enzyme. Our results demonstrate that GR affects the transcriptional status of a number of regulatory processes during late fetal lung development. Amongst these processes is cell proliferation whereby GR induces expression of cell cycle repressors while suppressing induction of a well characterized cell cycle stimulator. PMID:17901120

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

    SciTech Connect

    Zhang, Fenxi; Hong, Yan; Liang, Wenmei; Ren, Tongming; Jing, Suhua; Lin, Juntang

    2012-10-12

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

  15. Caffeine Positively Modulates Ferritin Heavy Chain Expression in H460 Cells: Effects on Cell Proliferation.

    PubMed

    Zolea, Fabiana; Biamonte, Flavia; Battaglia, Anna Martina; Faniello, Maria Concetta; Cuda, Giovanni; Costanzo, Francesco

    Both the methylxanthine caffeine and the heavy subunit of ferritin molecule (FHC) are able to control the proliferation rate of several cancer cell lines. While caffeine acts exclusively as a negative modulator of cell proliferation, FHC might reduce or enhance cell viability depending upon the different cell type. In this work we have demonstrated that physiological concentrations of caffeine reduce the proliferation rate of H460 cells: along with the modulation of p53, pAKT and Cyclin D1, caffeine also determines a significant FHC up-regulation through the activation of its transcriptional efficiency. FHC plays a central role in the molecular pathways modulated by caffeine, ending in a reduced cell growth, since its specific silencing by siRNA almost completely abolishes caffeine effects on H460 cell proliferation. These results allow the inclusion of ferritin heavy subunits among the multiple molecular targets of caffeine and open the way for studying the relationship between caffeine and intracellular iron metabolism.

  16. 17β-Estradiol treatment inhibits breast cell proliferation, migration and invasion by decreasing MALAT-1 RNA level

    SciTech Connect

    Zhao, Ziyi; Chen, Changjin; Liu, Yu; Wu, Chuanfang

    2014-03-07

    Highlights: • E2 affects not only estrogen-receptor α positive breast cells but also negative ones. • 100 nM E2 treatment affects breast cells proliferation, migration. • 100 nM E2 treatment functions in an estrogen-receptor α-independent way. • E2 treatment decreases MALAT-1 RNA level by post-transcriptional regulation. - Abstract: Breast cancer cells, which express estrogen receptor α (ERα), respond to estrogen in a concentration dependent fashion, resulting in proliferation or apoptosis. But breast cancer cells without ERα show no effect on low concentration of estrogen treatment. Proliferation, migration and invasion of MCF10a, MCF7 and MB231 cells treated with low (1 nM) or high (100 nM) dose of 17β-Estradiol (E2) was performed. We identified the effects of E2 on these breast cell lines, and looked for the difference in the presence and absence of ERα. Specifically, we looked for the changes of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1), which is found extensively and highly expressed in several kinds of tumor cells, including breast carcinoma. It was observed that proliferation, migration and invasion of breast cells were greatly affected by high concentration E2 treatment and were not affected by low concentration E2 treatment in an ERα independent way. We found that the high concentration E2 treatment largely decreased MALAT-1 RNA level. Interestingly, MALAT-1 decreasing by knocking down showed similar effects on proliferation, migration and invasion. E2 treatment affects breast tumor or non-tumor cells proliferation, migration and invasion in an ERα -independent, but a dose-dependent way by decreasing the MALAT-1 RNA level.

  17. Lipocalin-2 inhibits osteoclast formation by suppressing the proliferation and differentiation of osteoclast lineage cells

    SciTech Connect

    Kim, Hyun-Ju; Yoon, Hye-Jin; Yoon, Kyung-Ae; Gwon, Mi-Ri; Jin Seong, Sook; Suk, Kyoungho; Kim, Shin-Yoon; Yoon, Young-Ran

    2015-06-10

    Lipocalin-2 (LCN2) is a member of the lipocalin superfamily and plays a critical role in the regulation of various physiological processes, such as inflammation and obesity. In this study, we report that LCN2 negatively modulates the proliferation and differentiation of osteoclast precursors, resulting in impaired osteoclast formation. The overexpression of LCN2 in bone marrow-derived macrophages or the addition of recombinant LCN2 protein inhibits the formation of multinuclear osteoclasts. LCN2 suppresses macrophage colony-stimulating factor (M-CSF)-induced proliferation of osteoclast precursor cells without affecting their apoptotic cell death. Interestingly, LCN2 decreases the expression of the M-CSF receptor, c-Fms, and subsequently blocks its downstream signaling cascades. In addition, LCN2 inhibits RANKL-induced osteoclast differentiation and attenuates the expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which are important modulators in osteoclastogenesis. Mechanistically, LCN2 inhibits NF-κB signaling pathways, as demonstrated by the suppression of IκBα phosphorylation, nuclear translocation of p65, and NF-κB transcriptional activity. Thus, LCN2 is an anti-osteoclastogenic molecule that exerts its effects by retarding the proliferation and differentiation of osteoclast lineage cells. - Highlights: • LCN2 expression is regulated during osteoclast development. • LCN2 suppresses M-CSF-mediated osteoclast precursor proliferation. • LCN2 inhibits RANKL-induced osteoclast differentiation.

  18. Effect of mechanical and electrical behavior of gelatin hydrogels on drug release and cell proliferation.

    PubMed

    Biswal, Dibyajyoti; Anupriya, B; Uvanesh, K; Anis, Arfat; Banerjee, Indranil; Pal, Kunal

    2016-01-01

    The present study was aimed to explore the effect of the mechanical and the electrical properties of the gelatin hydrogels on the mammalian cell proliferation and drug release properties. FTIR analysis of the hydrogels suggested that gelatin retained its secondary protein structure. A decrease in the diffusion constant of the water molecules was observed with the increase in the gelatin concentration in the hydrogels. The mechanical and the electrical stabilities of the hydrogels were enhanced with the increase in the gelatin content. Stress relaxation and creep studies were modeled using Weichert and Burger׳s models, respectively. The relaxation time (stress relaxation study) did not follow a concentration-dependent relationship and was found to affect the MG-63 cell (human osteoblast) proliferation. The impedance profile of the hydrogels was modeled using a (RQ)Q model. Release of ciprofloxacin from the hydrogels was inversely dependent on the rate of swelling. The release of the drug was not only dependent on the Fickian diffusion but also on the relaxation process of the gelatin chains. The inhomogeneous constant of the constant phase element representing the hydrogel-electrode interface indicated improved cell proliferation rate with a decrease in the inhomogeneous constant. In gist, the rate of cell proliferation could be related to the relaxation time (stress relaxation) and the inhomogeneous constant of the sample-electrode constant phase element (electrical study) properties, whereas, the drug release properties can be related to the bulk resistance of the formulations.

  19. mTORC1 pathway mediates beta cell compensatory proliferation in 60 % partial-pancreatectomy mice.

    PubMed

    Li, Wenyi; Zhang, Hongli; Nie, Aifang; Ni, Qicheng; Li, Fengying; Ning, Guang; Li, Xiaoying; Gu, Yanyun; Wang, Qidi

    2016-07-01

    Beta cell replication is the major component for maintenance of beta cell mass in adult rodents; however, little is known about what is the earliest signals that initiate rodent beta cell proliferation. The mTORC1 pathway integrates signals from growth factors and nutrients and regulates cell growth and survival. Here, we used normoglycemic 60 % partial-pancreatectomy (60 % Px) mouse model to determine whether mTORC1 pathway was required for compensatory beta cell proliferation. C57BL/6 J male mice were subjected to 60 % Px or sham operation, and subsequently treated with either rapamycin or vehicle for 7 days. Metabolic profile, pancreatic beta cell mass, and proliferation were examined, and expression levels of cell cycle regulators were determined. Beta cell proliferation was increased by 2.5-fold, and mTORC1 signaling was activated in islets post-Px. Rapamycin treatment impaired glucose tolerance and glucose stimulating insulin secretion in 60 % Px mice, but did not affect their insulin sensitivity in peripheral tissue. Rapamycin inhibited mTORC1 activity in beta cells, suppressed compensatory beta cell proliferation and growth, and reduced beta cell mass and insulin content in 60 % Px mice. Px caused an increase of the cyclin D2 at protein level and promoted cyclin D2 nuclear localization in an mTOR-dependent manner. Disrupting mTORC1 signaling suppressed cell proliferation and simultaneously diminished cyclin D2 protein abundance in RINm5F cells. Our data demonstrated that mTORC1 plays an essential role in beta cell adaption to significant beta cell mass loss in 60 % Px model and in early compensatory beta cell proliferation via cyclin D2 pathway.

  20. Iron chelators target both proliferating and quiescent cancer cells

    PubMed Central

    Fryknäs, Mårten; Zhang, Xiaonan; Bremberg, Ulf; Senkowski, Wojciech; Olofsson, Maria Hägg; Brandt, Peter; Persson, Ingmar; D’Arcy, Padraig; Gullbo, Joachim; Nygren, Peter; Schughart, Leoni Kunz; Linder, Stig; Larsson, Rolf

    2016-01-01

    Poorly vascularized areas of solid tumors contain quiescent cell populations that are resistant to cell cycle-active cancer drugs. The compound VLX600 was recently identified to target quiescent tumor cells and to inhibit mitochondrial respiration. We here performed gene expression analysis in order to characterize the cellular response to VLX600. The compound-specific signature of VLX600 revealed a striking similarity to signatures generated by compounds known to chelate iron. Validation experiments including addition of ferrous and ferric iron in excess, EXAFS measurements, and structure activity relationship analyses showed that VLX600 chelates iron and supported the hypothesis that the biological effects of this compound is due to iron chelation. Compounds that chelate iron possess anti-cancer activity, an effect largely attributed to inhibition of ribonucleotide reductase in proliferating cells. Here we show that iron chelators decrease mitochondrial energy production, an effect poorly tolerated by metabolically stressed tumor cells. These pleiotropic features make iron chelators an attractive option for the treatment of solid tumors containing heterogeneous populations of proliferating and quiescent cells. PMID:27924826

  1. SerpinB1 Promotes Pancreatic β Cell Proliferation

    SciTech Connect

    El Ouaamari, Abdelfattah; Dirice, Ercument; Gedeon, Nicholas; Hu, Jiang; Zhou, Jian-Ying; Shirakawa, Jun; Hou, Lifei; Goodman, Jessica; Karampelias, Christos; Qiang, Guifeng; Boucher, Jeremie; Martinez, Rachael; Gritsenko, Marina A.; De Jesus, Dario F.; Kahraman, Sevim; Bhatt, Shweta; Smith, Richard D.; Beer, Hans-Dietmar; Jungtrakoon, Prapaporn; Gong, Yanping; Goldfine, Allison B.; Liew, Chong Wee; Doria, Alessandro; Andersson, Olov; Qian, Wei-Jun; Remold-O’Donnell, Eileen; Kulkarni, Rohit N.

    2016-01-01

    Compensatory β-cell growth in response to insulin resistance is a common feature in diabetes. We recently reported that liver-derived factors participate in this compensatory response in the liver insulin receptor knockout (LIRKO) mouse, a model of significant islet hyperplasia. Here we show that serpinB1 is a liver-derived secretory protein that controls β-cell proliferation. SerpinB1 is abundant in the hepatocyte secretome and sera derived from LIRKO mice. SerpinB1 and small molecule compounds that partially mimic serpinB1 activity enhanced proliferation of zebrafish, mouse and human β-cells. We report that serpinB1-induced β-cell replication requires protease inhibition activity and mice lacking serpinB1 exhibit attenuated β-cell replication in response to insulin resistance. Finally, SerpinB1-treatment of islets modulated signaling proteins in growth and survival pathways such as MAPK, PKA and GSK3. Together, these data implicate SerpinB1 as a protein that can potentially be harnessed to enhance functional β-cell mass in patients with diabetes.

  2. Fractalkine-induced smooth muscle cell proliferation in pulmonary hypertension.

    PubMed

    Perros, F; Dorfmüller, P; Souza, R; Durand-Gasselin, I; Godot, V; Capel, F; Adnot, S; Eddahibi, S; Mazmanian, M; Fadel, E; Hervé, P; Simonneau, G; Emilie, D; Humbert, M

    2007-05-01

    Pulmonary hypertension is characterised by a progressive increase in pulmonary arterial resistance due to endothelial and smooth muscle cell proliferation resulting in chronic obstruction of small pulmonary arteries. There is evidence that inflammatory mechanisms may contribute to the pathogenesis of human and experimental pulmonary hypertension. The aim of the study was to address the role of fractalkine (CX3CL1) in the inflammatory responses and pulmonary vascular remodelling of a monocrotaline-induced pulmonary hypertension model. The expression of CX3CL1 and its receptor CX3CR1 was studied in monocrotaline-induced pulmonary hypertension by means of immunohistochemistry and quantitative reverse-transcription PCR on laser-captured microdissected pulmonary arteries. It was demonstrated that CX3CL1 was expressed by inflammatory cells surrounding pulmonary arterial lesions and that smooth muscle cells from these vessels had increased CX3CR1 expression. It was then shown that cultured rat pulmonary artery smooth muscle cells expressed CX3CR1 and that CX3CL1 induced proliferation but not migration of these cells. In conclusion, the current authors proposed that fractalkine may act as a growth factor for pulmonary artery smooth muscle cells. Chemokines may thus play a role in pulmonary artery remodelling.

  3. Transient fluctuations of intracellular zinc ions in cell proliferation

    SciTech Connect

    Li, Yuan; Maret, Wolfgang

    2009-08-15

    Zinc is essential for cell proliferation, differentiation, and viability. When zinc becomes limited for cultured cells, DNA synthesis ceases and the cell cycle is arrested. The molecular mechanisms of actions of zinc are believed to involve changes in the availability of zinc(II) ions (Zn{sup 2+}). By employing a fluorescent Zn{sup 2+} probe, FluoZin-3 acetoxymethyl ester, intracellular Zn{sup 2+} concentrations were measured in undifferentiated and in nerve growth factor (NGF)-differentiated rat pheochromocytoma (PC12) cells. Intracellular Zn{sup 2+} concentrations are pico- to nanomolar in PC12 cells and are higher in the differentiated than in the undifferentiated cells. When following cellular Zn{sup 2+} concentrations for 48 h after the removal of serum, a condition that is known to cause cell cycle arrest, Zn{sup 2+} concentrations decrease after 30 min but, remarkably, increase after 1 h, and then decrease again to about one half of the initial concentration. Cell proliferation, measured by an MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, decreases after both serum starvation and zinc chelation. Two peaks of Zn{sup 2+} concentrations occur within one cell cycle: one early in the G1 phase and the other in the late G1/S phase. Thus, fluctuations of intracellular Zn{sup 2+} concentrations and established modulation of phosphorylation signaling, via an inhibition of protein tyrosine phosphatases at commensurately low Zn{sup 2+} concentrations, suggest a role for Zn{sup 2+} in the control of the cell cycle. Interventions targeted at these picomolar Zn{sup 2+} fluctuations may be a way of controlling cell growth in hyperplasia, neoplasia, and diseases associated with aberrant differentiation.

  4. Mobile phone radiation alters proliferation of hepatocarcinoma cells.

    PubMed

    Ozgur, Elcin; Guler, Goknur; Kismali, Gorkem; Seyhan, Nesrin

    2014-11-01

    This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3, or 4 h, at a specific absorption rate of 2 W/kg) to enhanced data rates for global system for mobile communication evolution-modulated radiofrequency radiation (RFR) at 900- and 1,800-MHz frequencies on the viability of the Hepatocarcinoma cells (Hep G2). Hep G2 cell proliferation was measured by a colorimetric assay based on the cleavage of the tetrazolium salt WST-1 by mitochondrial dehydrogenases in viable cells. Cell injury was evaluated by analyzing the levels of lactate dehydrogenase (LDH) and glucose released from lysed cells into the culture medium. Morphological observation of the nuclei was carried out by 4',6-diamidino-2-phenylindole (DAPI) staining using fluorescence microscopy. In addition, TUNEL assay was performed to confirm apoptotic cell death. It was observed that cell viability, correlated with the LDH and glucose levels, changed according to the frequency and duration of RFR exposure. Four-hour exposure produced more pronounced effects than the other exposure durations. 1,800-MHz RFR had a larger impact on cell viability and Hep G2 injury than the RFR at 900 MHz. Morphological observations also supported the biochemical results indicating that most of the cells showed irregular nuclei pattern determined by using the DAPI staining, as well as TUNEL assay which shows DNA damage especially in the cells after 4 h of exposure to 1,800-MHz RFR. Our results indicate that the applications of 900- and 1,800-MHz (2 W/kg) RFR cause to decrease in the proliferation of the Hep G2 cells after 4 h of exposure. Further studies will be conducted on other frequency bands of RFR and longer duration of exposure.

  5. Nox4-generated superoxide drives angiotensin II-induced neural stem cell proliferation.

    PubMed

    Topchiy, Elena; Panzhinskiy, Evgeniy; Griffin, W Sue T; Barger, Steven W; Das, Mita; Zawada, W Michael

    2013-01-01

    Reactive oxygen species (ROS) have been reported to affect neural stem cell self-renewal and therefore may be important for normal development and may influence neurodegenerative processes when ROS activity is elevated. To determine if increasing production of superoxide, via activation of NADPH oxidase (Nox), increases neural stem cell proliferation, 100 nM angiotensin II (Ang II) - a strong stimulator of Nox - was applied to cultures of a murine neural stem cell line, C17.2. Twelve hours following a single treatment with Ang II, there was a doubling of the number of neural stem cells. This increase in neural stem cell numbers was preceded by a gradual elevation of superoxide levels (detected by dihydroethidium fluorescence) from the steady state at 0, 5, and 30 min and gradually increasing from 1 h to the maximum at 12 h, and returning to baseline at 24 h. Ang II-dependent proliferation was blocked by the antioxidant N-acetyl-L-cysteine. Confocal microscopy revealed the presence of two sources of intracellular ROS in C17.2 cells: (i) mitochondrial and (ii) extramitochondrial; the latter indicative of the involvement of one or more specific isoforms of Nox. Of the Nox family, mRNA expression for one member, Nox4, is abundant in neural stem cell cultures, and Ang II treatment resulted in elevation of the relative levels of Nox4 protein. SiRNA targeting of Nox4 mRNA reduced both the constitutive and Ang II-induced Nox4 protein levels and attenuated Ang II-driven increases in superoxide levels and stem cell proliferation. Our findings are consistent with our hypothesis that Ang II-induced proliferation of neural stem cells occurs via Nox4-generated superoxide, suggesting that an Ang II/Nox4 axis is an important regulator of neural stem cell self-renewal and as such may fine-tune normal, stress- or disease-modifying neurogenesis.

  6. Nox4-generated superoxide drives angiotensin II-induced neural stem cell proliferation

    PubMed Central

    Topchiy, Elena; Panzhinskiy, Evgeniy; Griffin, W. Sue T.; Barger, Steven W.; Das, Mita; Zawada, W. Michael

    2013-01-01

    Reactive oxygen species (ROS) have been reported to affect neural stem cell self-renewal and therefore may be important for normal development and may influence neurodegenerative processes when ROS activity is elevated. To determine if increasing production of superoxide, via activation of NADPH oxidase (Nox), increases neural stem cell proliferation, 100nM angiotensin II (Ang II) – a strong stimulator of Nox – was applied to cultures of a murine neural stem cell line C17.2. Twelve hours following a single treatment with Ang II there was a doubling of the number of neural stem cells. This increase in neural stem cell numbers was preceded by a gradual elevation of superoxide levels (detected by dihydroethidium, DHE, fluorescence) from the steady state at 0, 5, and 30 minutes and gradually increasing from one hour to the maximum at 12 h, and returning to baseline at 24 h. Ang II-dependent proliferation was blocked by the antioxidant N-acetyl-L-cysteine (NAC). Confocal microscopy revealed the presence of two sources of intracellular ROS in C17.2 cells: i) mitochondrial and ii) extramitochondrial; the latter indicative of involvement of one or more specific isoforms of Nox. Of the Nox family, mRNA expression for one member, Nox4, is abundant in neural stem cell cultures, and Ang II treatment resulted in elevation of the relative levels of Nox4 protein. SiRNA targeting of Nox4 mRNA reduced both the constitutive and Ang II-induced Nox4 protein levels and attenuated Ang II-driven increases in superoxide levels and stem cell proliferation. Our findings are consistent with our hypothesis that Ang II-induced proliferation of neural stem cells occurs via Nox4-generated superoxide, suggesting that an Ang II/Nox4 axis is an important regulator of neural stem cell self-renewal and as such may fine-tune normal or stress- or disease-modifying neurogenesis. PMID:23751520

  7. Splicing factors PTBP1 and PTBP2 promote proliferation and migration of glioma cell lines

    PubMed Central

    Cheung, Hannah C.; Hai, Tao; Zhu, Wen; Baggerly, Keith A.; Tsavachidis, Spiridon; Krahe, Ralf

    2009-01-01

    Polypyrimidine tract-binding protein 1 (PTBP1) is a multi-functional RNA-binding protein that is aberrantly overexpressed in glioma. PTBP1 and its brain-specific homologue polypyrimidine tract-binding protein 2 (PTBP2) regulate neural precursor cell differentiation. However, the overlapping and non-overlapping target transcripts involved in this process are still unclear. To determine why PTBP1 and not PTBP2 would promote glial cell-derived tumours, both PTBP1 and PTBP2 were knocked down in the human glioma cell lines U251 and LN229 to determine the role of these proteins in cell proliferation, migration, and adhesion. Surprisingly, removal of both PTBP1 and PTBP2 slowed cell proliferation, with the double knockdown having no additive effects. Decreased expression of both proteins individually and in combination inhibited cell migration and increased adhesion of cells to fibronectin and vitronectin. A global survey of differential exon expression was performed following PTBP1 knockdown in U251 cells using the Affymetrix Exon Array to identify PTBP1-specific splicing targets that enhance gliomagenesis. In the PTBP1 knockdown, previously determined targets were unaltered in their splicing patterns. A single gene, RTN4 (Nogo) had significantly enhanced inclusion of exon 3 when PTBP1 was removed. Overexpression of the splice isoform containing exon 3 decreased cell proliferation to a similar degree as the removal of PTBP1. These results provide the first evidence that RNA-binding proteins affect the invasive and rapid growth characteristics of glioma cell lines. Its actions on proliferation appear to be mediated, in part, through alternative splicing of RTN4. PMID:19506066

  8. Polycomb proteins control proliferation and transformation independently of cell cycle checkpoints by regulating DNA replication.

    PubMed

    Piunti, Andrea; Rossi, Alessandra; Cerutti, Aurora; Albert, Mareike; Jammula, Sriganesh; Scelfo, Andrea; Cedrone, Laura; Fragola, Giulia; Olsson, Linda; Koseki, Haruhiko; Testa, Giuseppe; Casola, Stefano; Helin, Kristian; d'Adda di Fagagna, Fabrizio; Pasini, Diego

    2014-04-14

    The ability of PRC1 and PRC2 to promote proliferation is a main feature that links polycomb (PcG) activity to cancer. PcGs silence the expression of the tumour suppressor locus Ink4a/Arf, whose products positively regulate pRb and p53 functions. Enhanced PcG activity is a frequent feature of human tumours, and PcG inhibition has been proposed as a strategy for cancer treatment. However, the recurrent inactivation of pRb/p53 responses in human cancers raises a question regarding the ability of PcG proteins to affect cellular proliferation independently from this checkpoint. Here we demonstrate 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 activity by which PcGs can regulate cell proliferation independently of major cell cycle restriction checkpoints.

  9. APE/Ref-1 makes fine-tuning of CD40-induced B cell proliferation

    PubMed Central

    Merluzzi, Sonia; Gri, Giorgia; Gattei, Valter; Pagano, Michele; Pucillo, Carlo

    2009-01-01

    Apurinic/apyrimidinic endonuclease-1/Redox factor-1, a multifunctional DNA base excision repair and redox regulation enzyme, plays an important role in oxidative signalling, transcription factor regulation, and cell cycle control. Recently, we have demonstrated that following the triggering of CD40 on B cells, APE/Ref-1 translocates from the cytoplasm to the nucleus and regulates the activity of B cell-specific transcription factors. In the present paper we investigate whether APE/Ref-1 plays a role in controlling CD40-mediated B cell proliferation too. We demonstrate a concurrent increase in proliferation and decrease in apoptosis of primary mouse B cells activated by CD40 cross-linking and transfected with functional APE/Ref-1 antisense oligonucleotide. Moreover, we provide evidence that a redox-mediated signalling mechanism is involved in this process and we propose that APE/Ref-1, controlling the intracellular redox state, may also affect the cell cycle by inducing nucleus-cytoplasm redistribution of p21. Together, these findings suggest that APE/Ref-1 could act as a negative regulator in an adaptive response to elevated ROS levels following CD40 cross-linking. Considering the important role of ROS and APE/Ref-1 in CD40-mediated B cell proliferation, our data will contribute to understand the mechanisms of tumor escape and suggest APE/Ref-1 as a novel target for tumor therapeutic approaches. PMID:18617267

  10. Balanced cell proliferation and expansion is essential for flowering stem growth control.

    PubMed

    Ferjani, Ali; Hanai, Kenya; Gunji, Shizuka; Maeda, Saori; Sawa, Shinichiro; Tsukaya, Hirokazu

    2015-01-01

    The postembryonic development of aboveground plant organs relies on a continuous supply of cells from the shoot apical meristem. Previous studies of developmental regulation in leaves and flowers have revealed the crucial role of coordinated cell proliferation and differentiation during organogenesis. However, the importance of this coordination has not been examined in flowering stems. Very recently, we attempted to identify regulatory factors that maintain flowering stem integrity. We found that the increased cell number in clavata (clv) mutants and the decreased cell size in de-etiolated (det)3-1 resulted in flowering stems that were thicker and thinner, respectively, than in wild-type (WT) plants. Interestingly, in the cell proliferation- and cell expansion-defective double mutant clv det3-1, the flowering stems often exhibited severe cracking, resulting in exposure of their inner tissues. In this study, further quantification of the cellular phenotypes in the cotyledons and leaves revealed no differences between det3-1 and clv3 det3-1. Together, the above findings suggest that the clv3 mutation in a det3-1 background primarily affects flowering stems, while its effect on other organs is likely negligible. We propose that the coordination between cell proliferation and differentiation is not only important during leaf development, but also plays a role in the growth control of Arabidopsis flowering stems.

  11. Balanced cell proliferation and expansion is essential for flowering stem growth control

    PubMed Central

    Ferjani, Ali; Hanai, Kenya; Gunji, Shizuka; Maeda, Saori; Sawa, Shinichiro; Tsukaya, Hirokazu

    2015-01-01

    The postembryonic development of aboveground plant organs relies on a continuous supply of cells from the shoot apical meristem. Previous studies of developmental regulation in leaves and flowers have revealed the crucial role of coordinated cell proliferation and differentiation during organogenesis. However, the importance of this coordination has not been examined in flowering stems. Very recently, we attempted to identify regulatory factors that maintain flowering stem integrity. We found that the increased cell number in clavata (clv) mutants and the decreased cell size in de-etiolated (det)3-1 resulted in flowering stems that were thicker and thinner, respectively, than in wild-type (WT) plants. Interestingly, in the cell proliferation- and cell expansion-defective double mutant clv det3-1, the flowering stems often exhibited severe cracking, resulting in exposure of their inner tissues. In this study, further quantification of the cellular phenotypes in the cotyledons and leaves revealed no differences between det3-1 and clv3 det3-1. Together, the above findings suggest that the clv3 mutation in a det3-1 background primarily affects flowering stems, while its effect on other organs is likely negligible. We propose that the coordination between cell proliferation and differentiation is not only important during leaf development, but also plays a role in the growth control of Arabidopsis flowering stems. PMID:25831425

  12. Cyclin C stimulates β-cell proliferation in rat and human pancreatic β-cells

    PubMed Central

    Jiménez-Palomares, Margarita; López-Acosta, José Francisco; Villa-Pérez, Pablo; Moreno-Amador, José Luis; Muñoz-Barrera, Jennifer; Fernández-Luis, Sara; Heras-Pozas, Blanca; Perdomo, Germán; Bernal-Mizrachi, Ernesto

    2015-01-01

    Activation of pancreatic β-cell proliferation has been proposed as an approach to replace reduced functional β-cell mass in diabetes. Quiescent fibroblasts exit from G0 (quiescence) to G1 through pRb phosphorylation mediated by cyclin C/cdk3 complexes. Overexpression of cyclin D1, D2, D3, or cyclin E induces pancreatic β-cell proliferation. We hypothesized that cyclin C overexpression would induce β-cell proliferation through G0 exit, thus being a potential therapeutic target to recover functional β-cell mass. We used isolated rat and human islets transduced with adenovirus expressing cyclin C. We measured multiple markers of proliferation: [3H]thymidine incorporation, BrdU incorporation and staining, and Ki67 staining. Furthermore, we detected β-cell death by TUNEL, β-cell differentiation by RT-PCR, and β-cell function by glucose-stimulated insulin secretion. Interestingly, we have found that cyclin C increases rat and human β-cell proliferation. This augmented proliferation did not induce β-cell death, dedifferentiation, or dysfunction in rat or human islets. Our results indicate that cyclin C is a potential target for inducing β-cell regeneration. PMID:25564474

  13. Association between SET expression and glioblastoma cell apoptosis and proliferation.

    PubMed

    He, Kunyan; Shi, Lihong; Jiang, Tingting; Li, Qiang; Chen, Yao; Meng, Chuan

    2016-10-01

    Glioblastoma multiforme (GBM) was one of the first cancer types systematically studied at a genomic and transcriptomic level due to its high incidence and aggressivity; however, the detailed mechanism remains unclear, even though it is known that numerous cytokines are involved in the occurrence and development of GBM. The present study aimed to determine whether the SET gene has a role in human glioblastoma carcinogenesis. A total of 32 samples, including 18 cases of glioma, 2 cases of meningioma and 12 normal brain tissue samples, were detected using the streptavidin-peroxidase method through immunohistochemistry. To reduce SET gene expression in U251 and U87MG cell lines, the RNA interference technique was used and transfection with small interfering (si)RNA of the SET gene was performed. Cell apoptosis was detected by flow cytometry, cell migration was examined by Transwell migration assay and cell proliferation was determined by Cell Counting Kit-8. SET, Bcl-2, Bax and caspase-3 mRNA and protein expression levels were detected by reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. Positive protein expression of SET was observed in the cell nucleus, with the expression level of SET significantly higher in glioma tissues compared with normal brain tissue (P=0.001). Elevated expression of SET was significantly associated with gender (P=0.002), tumors classified as World Health Organization grade II (P=0.031), III (P=0.003) or IV (P=0.001), and moderately (P=0.031) or poorly differentiated (P=0.001) tumors. Compared with the negative and non-treatment (blank) control cells, SET gene expression was significantly inhibited (P=0.006 and P<0.001), cell apoptosis was significantly increased (P=0.001 and P<0.001), cell proliferation was significantly inhibited (P=0.002 and P=0.015), and cell migration was significantly decreased (P=0.001 and P=0.001) in siRNA-transfected U87MG(-SET) and U251(-SET) cells, respectively. In

  14. Cell type specific applicability of 5-ethynyl-2'-deoxyuridine (EdU) for dynamic proliferation assessment in flow cytometry.

    PubMed

    Diermeier-Daucher, Simone; Clarke, Scott T; Hill, Dani; Vollmann-Zwerenz, Arabel; Bradford, Jolene A; Brockhoff, Gero

    2009-06-01

    Using the nucleoside analogue EdU (5-ethynyl-2'-deoxyuridine) for thymidine substitution instead of BrdU (5-bromo-2'-deoxyuridine) in cell proliferation assays has recently been proposed. However, the effect of EdU on cell viability, DNA synthesis, and cell cycle progression and consequently its usability for dynamic cell proliferation analysis in vitro has not been explored. We compared the effect of EdU and BrdU incorporation into SK-BR-3 and BT474 breast cancer cells and the impact on cell cycle kinetics, cell viability, and DNA damage. We found that EdU can be used not only for pulse but also for continuous cell labeling and henceforth in high resolution EdU/Hoechst quenching assays. BrdU and EdU proliferation assays based on click chemistry revealed comparable results. However, cell viability of SK-BR-3 breast cancer cells was highly affected by long term exposure to EdU. Both SK-BR-3 as well as BT474 cells show cell cycle arrests upon long term EdU treatment whereas only SK-BR-3 cells were driven into necrotic cell death by long term exposure to EdU. In contrast BT474 cells appeared essentially unharmed by EdU treatment in terms of viability. Consequently using EdU enables highly sensitive and quantitative detection of proliferating cells and facilitates even continuous cell cycle assessment. Nevertheless, potential cellular susceptibility needs to be individually evaluated.

  15. In Vitro Proliferation of Porcine Pancreatic Islet Cells for β-Cell Therapy Applications

    PubMed Central

    Niu, Guoguang; McQuilling, John P.; Zhou, Yu; Opara, Emmanuel C.; Orlando, Giuseppe

    2016-01-01

    β-Cell replacement through transplantation is the only curative treatment to establish a long-term stable euglycemia in diabetic patients. Owing to the shortage of donor tissue, attempts are being made to develop alternative sources of insulin-secreting cells. Stem cells differentiation and reprograming as well as isolating pancreatic progenitors from different sources are some examples; however, no approach has yet yielded a clinically relevant solution. Dissociated islet cells that are cultured in cell numbers by in vitro proliferation provide a promising platform for redifferentiation towards β-cells phenotype. In this study, we cultured islet-derived cells in vitro and examined the expression of β-cell genes during the proliferation. Islets were isolated from porcine pancreases and enzymatically digested to dissociate the component cells. The cells proliferated well in tissue culture plates and were subcultured for no more than 5 passages. Only 10% of insulin expression, as measured by PCR, was preserved in each passage. High glucose media enhanced insulin expression by about 4–18 fold, suggesting a glucose-dependent effect in the proliferated islet-derived cells. The islet-derived cells also expressed other pancreatic genes such as Pdx1, NeuroD, glucagon, and somatostatin. Taken together, these results indicate that pancreatic islet-derived cells, proliferated in vitro, retained the expression capacity for key pancreatic genes, thus suggesting that the cells may be redifferentiated into insulin-secreting β-like cells. PMID:28050568

  16. Hepatocyte growth factor plays a dual role in regulating skeletal muscle satellite cell proliferation and differentiation.

    PubMed

    Gal-Levi, R; Leshem, Y; Aoki, S; Nakamura, T; Halevy, O

    1998-03-12

    The role of hepatocyte growth factor (HGF) and its receptor, c-met, in proliferation and differentiation of satellite cells was studied in primary cultures of chicken skeletal muscle satellite cells and a myogenic C2 cell line. HGF mRNA was expressed mainly in the myotubes of both cultures. The addition of conditioned medium derived from those cultures had a scattering effect on the canine kidney epithelial cell line, MDCK. In contrast, c-met mRNA levels decreased during cell differentiation of C2 and primary satellite cells. Application of exogenous HGF to chicken myoblasts resulted in their enhanced DNA synthesis. Among several growth factors, HGF was the first to induce DNA synthesis in quiescent satellite cells, thereby driving them into the cell cycle. Ectopic expression of chicken HGF in primary satellite cells suppressed the activation of muscle-regulatory gene reporter constructs MCK-CAT, MRF4-CAT, MEF2-CAT and 4Rtk-CAT, as well as the gene expression of MyoD and myogenin, and MHC protein expression. Ectopic MyoD reversed HGF's inhibitory effect on MCK transactivation. These data suggest that HGF inhibits cell differentiation by inhibiting the activity of basic helix-loop-helix (bHLH)/E protein heterodimers, thus inhibiting myogenic determination factor activity and subsequent muscle-specific protein expression. During muscle growth and regeneration, HGF plays a dual role in satellite-cell myogenesis, affecting both the proliferation and differentiation of these cells in a paracrine fashion.

  17. Surgical Marking Pen Dye Inhibits Saphenous Vein Cell Proliferation and Migration in Saphenous Vein Graft Tissue

    PubMed Central

    Kikuchi, Shinsuke; Kenagy, Richard D; Gao, Lu; Wight, Thomas N; Azuma, Nobuyoshi; Sobel, Michael; Clowes, Alexander W

    2014-01-01

    Objective Markers containing dyes such as crystal violet (CAS 548-62-9) are routinely used on the adventitia of vein bypass grafts to avoid twisting during placement. Since little is known about how these dyes affect vein graft healing and function, we determined the effect of crystal violet on cell migration and proliferation, which are responses to injury after grafting. Methods Fresh human saphenous veins were obtained as residual specimens from leg bypass surgeries. Portions of the vein that had been surgically marked with crystal violet were analyzed separately from those that had no dye marking. In the laboratory, they were split into easily dissected inner and outer layers after removal of endothelium. This f cleavage plane was within the circular muscle layer of the media. Cell migration from explants was measured daily as either 1) % migration positive explants, which exclusively measures migration, or 2) the number of cells on the plastic surrounding each explant, which measures migration plus proliferation. Cell proliferation and apoptosis (Ki67 and TUNEL staining, respectively) were determined in dye-marked and unmarked areas of cultured vein rings. The dose-dependent effects of crystal violet were measured for cell migration from explants as well as proliferation, migration, and death of cultured outer layer cells. Dye was extracted from explants with ethanol and quantified by spectrophotometry. Results There was significantly less cell migration from visibly blue, compared to unstained, outer layer explants by both methods. There was no significant difference in migration from inner layer explants adjacent to blue-stained or unstained sections of vein, because dye did not penetrate to the inner layer. Ki67 staining of vein in organ culture, which is a measure of proliferation, progressively increased up to 6 days in non-blue outer layer and was abolished in the blue outer layer. Evidence of apoptosis (TUNEL staining) was present throughout the wall

  18. Modelling T cell proliferation: Dynamics heterogeneity depending on cell differentiation, age, and genetic background

    PubMed Central

    2017-01-01

    Cell proliferation is the common characteristic of all biological systems. The immune system insures the maintenance of body integrity on the basis of a continuous production of diversified T lymphocytes in the thymus. This involves processes of proliferation, differentiation, selection, death and migration of lymphocytes to peripheral tissues, where proliferation also occurs upon antigen recognition. Quantification of cell proliferation dynamics requires specific experimental methods and mathematical modelling. Here, we assess the impact of genetics and aging on the immune system by investigating the dynamics of proliferation of T lymphocytes across their differentiation through thymus and spleen in mice. Our investigation is based on single-cell multicolour flow cytometry analysis revealing the active incorporation of a thymidine analogue during S phase after pulse-chase-pulse experiments in vivo, versus cell DNA content. A generic mathematical model of state transition simulates through Ordinary Differential Equations (ODEs) the evolution of single cell behaviour during various durations of labelling. It allows us to fit our data, to deduce proliferation rates and estimate cell cycle durations in sub-populations. Our model is simple and flexible and is validated with other durations of pulse/chase experiments. Our results reveal that T cell proliferation is highly heterogeneous but with a specific “signature” that depends upon genetic origins, is specific to cell differentiation stages in thymus and spleen and is altered with age. In conclusion, our model allows us to infer proliferation rates and cell cycle phase durations from complex experimental 5-ethynyl-2'-deoxyuridine (EdU) data, revealing T cell proliferation heterogeneity and specific signatures. PMID:28288157

  19. Modelling T cell proliferation: Dynamics heterogeneity depending on cell differentiation, age, and genetic background.

    PubMed

    Vibert, Julien; Thomas-Vaslin, Véronique

    2017-03-01

    Cell proliferation is the common characteristic of all biological systems. The immune system insures the maintenance of body integrity on the basis of a continuous production of diversified T lymphocytes in the thymus. This involves processes of proliferation, differentiation, selection, death and migration of lymphocytes to peripheral tissues, where proliferation also occurs upon antigen recognition. Quantification of cell proliferation dynamics requires specific experimental methods and mathematical modelling. Here, we assess the impact of genetics and aging on the immune system by investigating the dynamics of proliferation of T lymphocytes across their differentiation through thymus and spleen in mice. Our investigation is based on single-cell multicolour flow cytometry analysis revealing the active incorporation of a thymidine analogue during S phase after pulse-chase-pulse experiments in vivo, versus cell DNA content. A generic mathematical model of state transition simulates through Ordinary Differential Equations (ODEs) the evolution of single cell behaviour during various durations of labelling. It allows us to fit our data, to deduce proliferation rates and estimate cell cycle durations in sub-populations. Our model is simple and flexible and is validated with other durations of pulse/chase experiments. Our results reveal that T cell proliferation is highly heterogeneous but with a specific "signature" that depends upon genetic origins, is specific to cell differentiation stages in thymus and spleen and is altered with age. In conclusion, our model allows us to infer proliferation rates and cell cycle phase durations from complex experimental 5-ethynyl-2'-deoxyuridine (EdU) data, revealing T cell proliferation heterogeneity and specific signatures.

  20. Alterations of Cell Proliferation and Apoptosis in the Hypoplastic Reeler Cerebellum

    PubMed Central

    Cocito, Carolina; Merighi, Adalberto; Giacobini, Mario; Lossi, Laura

    2016-01-01

    A mutation of the reln gene gives rise to the Reeler mouse (reln−∕−) displaying an ataxic phenotype and cerebellar hypoplasia. We have characterized the neurochemistry of postnatal (P0–P60) reln−∕− mouse cerebella with specific attention to the intervention of cell proliferation and apoptosis in the P0–P25 interval. Homozygous reln−∕− mice and age-matched controls were analyzed by immunofluorescence using primary antibodies against NeuN, calbindin, GFAP, vimentin, SMI32, and GAD67. Proliferation and apoptosis were detected after a single intraperitoneal BrdU injection and by the TUNEL assay with anti-digoxigenin rhodamine-conjugated antibodies. Quantitative analysis with descriptive and predictive statistics was used to calculate cell densities (number/mm2) after fluorescent nuclear stain (TCD, total cell density), labeling with BrdU (PrCD, proliferating cell density), or TUNEL (ApoCD, apoptotic cell density). By this approach we first have shown that the temporal pattern of expression of neuronal/glial markers in postnatal cerebellum is not affected by the Reeler mutation. Then, we have demonstrated that the hypoplasia in the Reeler mouse cerebellum is consequent to reduction of cortical size and cellularity (TCD), and that TCD is, in turn, linked to quantitative differences in the extent of cell proliferation and apoptosis, as well as derangements in their temporal trends during postnatal maturation. Finally, we have calculated that PrCD is the most important predictive factor to determine TCD in the cerebellar cortex of the mutants. These results support the notion that, beside the well-known consequences onto the migration of the cerebellar neurons, the lack of Reelin results in a measurable deficit in neural proliferation. PMID:27252624

  1. Alterations of Cell Proliferation and Apoptosis in the Hypoplastic Reeler Cerebellum.

    PubMed

    Cocito, Carolina; Merighi, Adalberto; Giacobini, Mario; Lossi, Laura

    2016-01-01

    A mutation of the reln gene gives rise to the Reeler mouse (reln (-∕-)) displaying an ataxic phenotype and cerebellar hypoplasia. We have characterized the neurochemistry of postnatal (P0-P60) reln (-∕-) mouse cerebella with specific attention to the intervention of cell proliferation and apoptosis in the P0-P25 interval. Homozygous reln (-∕-) mice and age-matched controls were analyzed by immunofluorescence using primary antibodies against NeuN, calbindin, GFAP, vimentin, SMI32, and GAD67. Proliferation and apoptosis were detected after a single intraperitoneal BrdU injection and by the TUNEL assay with anti-digoxigenin rhodamine-conjugated antibodies. Quantitative analysis with descriptive and predictive statistics was used to calculate cell densities (number/mm(2)) after fluorescent nuclear stain (TCD, total cell density), labeling with BrdU (PrCD, proliferating cell density), or TUNEL (ApoCD, apoptotic cell density). By this approach we first have shown that the temporal pattern of expression of neuronal/glial markers in postnatal cerebellum is not affected by the Reeler mutation. Then, we have demonstrated that the hypoplasia in the Reeler mouse cerebellum is consequent to reduction of cortical size and cellularity (TCD), and that TCD is, in turn, linked to quantitative differences in the extent of cell proliferation and apoptosis, as well as derangements in their temporal trends during postnatal maturation. Finally, we have calculated that PrCD is the most important predictive factor to determine TCD in the cerebellar cortex of the mutants. These results support the notion that, beside the well-known consequences onto the migration of the cerebellar neurons, the lack of Reelin results in a measurable deficit in neural proliferation.

  2. Cytochromes P450 are expressed in proliferating cells in Barrett's metaplasia.

    PubMed

    Hughes, S J; Morse, M A; Weghorst, C M; Kim, H; Watkins, P B; Guengerich, F P; Orringer, M B; Beer, D G

    1999-06-01

    The expression of cytochromes P450 (CYP) in Barrett's esophagus and esophageal squamous mucosa was investigated. Esophagectomy specimens from 23 patients were examined for CYP expression of CYP1A2, CYP3A4, CYP2C9/10, and CYP2E1 by immunohistochemical analysis, and the expression of CYP1A1, CYP3A4, CYP1B1, CYP2E1, and CYP2C9/10 in these tissues was further confirmed by reverse transcription polymerase chain reaction. Immunohistochemical analysis of esophageal squamous mucosa (n = 12) showed expression of CYP1A2, CYP3A4, CYP2E1, and CYP2C9/10 proteins, but it was noted that cells within the basal proliferative zone did not express CYPs. Immunohistochemical analysis of Barrett's esophagus (n = 13) showed expression of CYP1A2, CYP3A4, CYP2E1, and CYP2C9/10 that was prominent in the basal glandular regions, which are areas containing a high percentage of actively proliferating cells. Immunohistochemical staining for both proliferating cell nuclear antigen and the CYPs further supported the colocalization of CYP expression to areas of active cell proliferation in Barrett's esophagus, whereas in the esophageal squamous epithelium, CYP expression is limited to cells that are not proliferating. RT-PCR with amplification product sequence analysis confirmed CYP1A1, CYP3A4, CYP1B1, CYP2E1, and CYP2C9/10 mRNA expression in Barrett's esophagus. These data suggest that the potential ability of cells in Barrett's esophagus to both activate carcinogens and proliferate may be important risk factors affecting carcinogenesis in this metaplastic tissue.

  3. Expression of WNT genes in cervical cancer-derived cells: Implication of WNT7A in cell proliferation and migration

    SciTech Connect

    Ramos-Solano, Moisés; Meza-Canales, Ivan D.; Torres-Reyes, Luis A.; Alvarez-Zavala, Monserrat; and others

    2015-07-01

    According to the multifactorial model of cervical cancer (CC) causation, it is now recognized that other modifications, in addition to Human papillomavirus (HPV) infection, are necessary for the development of this neoplasia. Among these, it has been proposed that a dysregulation of the WNT pathway might favor malignant progression of HPV-immortalized keratinocytes. The aim of this study was to identify components of the WNT pathway differentially expressed in CC vs. non-tumorigenic, but immortalized human keratinocytes. Interestingly, WNT7A expression was found strongly downregulated in cell lines and biopsies derived from CC. Restoration of WNT7A in CC-derived cell lines using a lentiviral gene delivery system or after adding a recombinant human protein decreases cell proliferation. Likewise, WNT7A silencing in non-tumorigenic cells markedly accelerates proliferation. Decreased WNT7A expression was due to hypermethylation at particular CpG sites. To our knowledge, this is the first study reporting reduced WNT7A levels in CC-derived cells and that ectopic WNT7A restoration negatively affects cell proliferation and migration. - Highlights: • WNT7A is expressed in normal keratinocytes or cervical cells without lesion. • WNT7A is significantly reduced in cervical cancer-derived cells. • Restoration of WNT7A expression in HeLa decreases proliferation and cell migration. • Silencing of WNT7A in HaCaT induces an increased proliferation and migration rate. • Decreased WNT7A expression in this model is due to hypermethylation.

  4. Social isolation prevents exercise-induced proliferation of hippocampal progenitor cells in female rats.

    PubMed

    Leasure, J Leigh; Decker, Linda

    2009-10-01

    Social isolation negatively affects the behavior and health of laboratory rats. Recently, it has been found that social isolation retards exercise-induced neurogenesis in the hippocampal dentate gyrus (DG) of male rats (Stranahan et al. (2006) Nat Neurosci 9:526-533). Since male and female rats react differently to housing changes and exercise opportunities, we investigated whether social isolation would also suppress the exercise-dependent increase in proliferation of dentate gyrus progenitor cells in females. Accordingly, female rats were housed either alone (isolated) or in groups (social) with (exercise) or without (sedentary) the opportunity to run in an exercise wheel. Proliferating progenitor cells were labeled with bromodeoxyuridine (BrdU). As expected, exercise increased the number of BrdU+ cells in socially housed animals. However, isolation prevented this running-induced increase. Our results expand upon previous findings by showing that the female brain is also susceptible to the suppressive effect of social isolation on exercise-induced neurogenesis.

  5. Germination of Arabidopsis Seed in Space and in Simulated Microgravity: Alterations in Root Cell Growth and Proliferation

    NASA Astrophysics Data System (ADS)

    Manzano, Ana I.; Matía, Isabel; González-Camacho, Fernando; Carnero-Díaz, Eugénie; van Loon, Jack J. W. A.; Dijkstra, Camelia; Larkin, Oliver; Anthony, Paul; Davey, Michael R.; Marco, Roberto; Medina, F. Javier

    2009-11-01

    Changes have been reported in the pattern of gene expression in Arabidopsis on exposure to microgravity. Plant cell growth and proliferation are functions that are potentially affected by such changes in gene expression. In the present investigation, the cell proliferation rate, the regulation of cell cycle progression and the rate of ribosome biogenesis (this latter taken to estimate cell growth) have been studied using morphometric markers or parameters evaluated by light and electron microscopy in real microgravity on the International Space Station (ISS) and in ground-based simulated microgravity, using the Random Positioning Machine and the Magnetic Levitation Instrument. Results showed enhanced cell proliferation but depleted cell growth in both real and simulated microgravity, indicating that the two processes are uncoupled, unlike the situation under normal gravity on Earth in which they are strictly co-ordinated events. It is concluded that microgravity is an important stress condition for plant cells compared to normal ground gravity conditions.

  6. Xanthohumol inhibits proliferation of laryngeal squamous cell carcinoma.

    PubMed

    Li, Yan; Wang, Kai; Yin, Shankai; Zheng, Hongliang; Min, Daliu

    2016-12-01

    Xanthohumol is a flavonoid compound that exhibits antioxidant and anticancer effects, and is used to treat atherosclerosis. The aim of the present study was to investigate the effect of xanthohumol on the cell proliferation of laryngeal squamous cell carcinoma and to understand the mechanism of its action. The effects of xanthohumol on the cell viability and apoptosis rate of laryngeal squamous cell carcinoma SCC4 cells were assessed by Annexin V-fluorescein isothiocyanate/propidium iodide staining. In addition, the expression levels of pro-apoptotic proteins, caspase-3, caspase-8, caspase-9, poly ADP ribose polymerase (PARP) p53 and apoptosis-inducing factor (AIF), as well as anti-apoptotic markers, B-cell lymphoma 2 (Bcl-2) and myeloid cell leukemia 1 (Mcl-1), were analyzed by western blotting. The results revealed that treatment with 40 µM xanthohumol significantly inhibited the proliferation of SCC4 cells. Furthermore, xanthohumol treatment (40 µM) induced SCC4 cell apoptosis, as indicated by the significant increase in activity and expression of caspase-3, caspase-8, caspase-9, PARP, p53 and AIF. By contrast, the protein expression of Bcl-2 and Mcl-1 was significantly decreased following treatment with 40 µM xanthohumol. Taken together, the results of the present study indicated that xanthohumol mediates growth suppression and apoptosis induction, which was mediated via the suppression of Bcl-2 and Mcl-1 and activation of PARP, p53 and AIF signaling pathways. Therefore, future studies that investigate xanthohumol as a potential therapeutic agent for laryngeal squamous cell carcinoma are required.

  7. Xanthohumol inhibits proliferation of laryngeal squamous cell carcinoma

    PubMed Central

    Li, Yan; Wang, Kai; Yin, Shankai; Zheng, Hongliang; Min, Daliu

    2016-01-01

    Xanthohumol is a flavonoid compound that exhibits antioxidant and anticancer effects, and is used to treat atherosclerosis. The aim of the present study was to investigate the effect of xanthohumol on the cell proliferation of laryngeal squamous cell carcinoma and to understand the mechanism of its action. The effects of xanthohumol on the cell viability and apoptosis rate of laryngeal squamous cell carcinoma SCC4 cells were assessed by Annexin V-fluorescein isothiocyanate/propidium iodide staining. In addition, the expression levels of pro-apoptotic proteins, caspase-3, caspase-8, caspase-9, poly ADP ribose polymerase (PARP) p53 and apoptosis-inducing factor (AIF), as well as anti-apoptotic markers, B-cell lymphoma 2 (Bcl-2) and myeloid cell leukemia 1 (Mcl-1), were analyzed by western blotting. The results revealed that treatment with 40 µM xanthohumol significantly inhibited the proliferation of SCC4 cells. Furthermore, xanthohumol treatment (40 µM) induced SCC4 cell apoptosis, as indicated by the significant increase in activity and expression of caspase-3, caspase-8, caspase-9, PARP, p53 and AIF. By contrast, the protein expression of Bcl-2 and Mcl-1 was significantly decreased following treatment with 40 µM xanthohumol. Taken together, the results of the present study indicated that xanthohumol mediates growth suppression and apoptosis induction, which was mediated via the suppression of Bcl-2 and Mcl-1 and activation of PARP, p53 and AIF signaling pathways. Therefore, future studies that investigate xanthohumol as a potential therapeutic agent for laryngeal squamous cell carcinoma are required. PMID:28105237

  8. Myosin VI contributes to malignant proliferation of human glioma cells

    PubMed Central

    Xu, Rong; Fang, Xu-hao

    2016-01-01

    Previously characterized as a backward motor, myosin VI (MYO6), which belongs to myosin family, moves toward the minus end of the actin track, a direction opposite to all other known myosin members. Recent researches have illuminated the role of MYO6 in human cancers, particularly in prostate cancer. However, the role of MYO6 in glioma has not yet been determined. In this study, to explore the role of MYO6 in human glioma, lentivirus-delivered short hairpin RNA (shRNA) targeting MYO6 was designed to stably down-regulate its endogenous expression in glioblastoma cells U251. Knockdown of MYO6 signifi cantly inhibited viability and proliferation of U251 cells in vitro. Moreover, the cell cycle of U251 cells was arrested at G0/G1 phase with the absence of MYO6, which could contribute to the suppression of cell proliferation. In conclusion, we firstly identified the crucial involvement of MYO6 in human glioma. The inhibition of MYO6 by shRNA might be a potential therapeutic method in human glioma. PMID:26937209

  9. Zinc signals promote IL-2-dependent proliferation of T cells.

    PubMed

    Kaltenberg, Jennifer; Plum, Laura M; Ober-Blöbaum, Julia L; Hönscheid, Andrea; Rink, Lothar; Haase, Hajo

    2010-05-01

    Zinc signals, i.e. a change of the intracellular concentration of free zinc ions in response to receptor stimulation, are involved in signal transduction in several immune cells. Here, the role of zinc signals in T-cell activation by IL-2 was investigated in the murine cytotoxic T-cell line CTLL-2 and in primary human T cells. Measurements with the fluorescent dyes FluoZin-3 and Zinquin showed that zinc is released from lysosomes into the cytosol in response to stimulation of the IL-2-receptor. Activation of the ERK-pathway was blocked by chelation of free zinc with N,N,N',N'-tetrakis-2(pyridyl-methyl)ethylenediamine, whereas zinc was not required for STAT5 phosphorylation. In addition, the key signaling molecules MEK and ERK were activated in response to elevated free intracellular zinc, induced by incubation with zinc and the ionophore pyrithione. Downstream of ERK activation, ERK-specific gene expression of c-fos and IL-2-induced proliferation was found to depend on zinc. Further experiments indicated that inhibition of MEK and ERK-dephosphorylating protein phosphatases is the molecular mechanism for the influence of zinc on this pathway. In conclusion, an increase of cytoplasmic free zinc is required for IL-2-induced ERK signaling and proliferation of T cells.

  10. Smooth Muscle Enriched Long Noncoding RNA (SMILR) Regulates Cell Proliferation

    PubMed Central

    Ballantyne, Margaret D.; Pinel, Karine; Dakin, Rachel; Vesey, Alex T.; Diver, Louise; Mackenzie, Ruth; Garcia, Raquel; Welsh, Paul; Sattar, Naveed; Hamilton, Graham; Joshi, Nikhil; Dweck, Marc R.; Miano, Joseph M.; McBride, Martin W.; Newby, David E.; McDonald, Robert A.

    2016-01-01

    Background— Phenotypic switching of vascular smooth muscle cells from a contractile to a synthetic state is implicated in diverse vascular pathologies, including atherogenesis, plaque stabilization, and neointimal hyperplasia. However, very little is known about the role of long noncoding RNA (lncRNA) during this process. Here, we investigated a role for lncRNAs in vascular smooth muscle cell biology and pathology. Methods and Results— Using RNA sequencing, we identified >300 lncRNAs whose expression was altered in human saphenous vein vascular smooth muscle cells following stimulation with interleukin-1α and platelet-derived growth factor. We focused on a novel lncRNA (Ensembl: RP11-94A24.1), which we termed smooth muscle–induced lncRNA enhances replication (SMILR). Following stimulation, SMILR expression was increased in both the nucleus and cytoplasm, and was detected in conditioned media. Furthermore, knockdown of SMILR markedly reduced cell proliferation. Mechanistically, we noted that expression of genes proximal to SMILR was also altered by interleukin-1α/platelet-derived growth factor treatment, and HAS2 expression was reduced by SMILR knockdown. In human samples, we observed increased expression of SMILR in unstable atherosclerotic plaques and detected increased levels in plasma from patients with high plasma C-reactive protein. Conclusions— These results identify SMILR as a driver of vascular smooth muscle cell proliferation and suggest that modulation of SMILR may be a novel therapeutic strategy to reduce vascular pathologies. PMID:27052414

  11. Biodiesel from soybean promotes cell proliferation in vitro.

    PubMed

    Gioda, Adriana; Rodríguez-Cotto, Rosa I; Amaral, Beatriz Silva; Encarnación-Medina, Jarline; Ortiz-Martínez, Mario G; Jiménez-Vélez, Braulio D

    2016-08-01

    Toxicological responses of exhaust emissions of biodiesel are different due to variation in methods of generation and the tested biological models. A chemical profile was generated using ICP-MS and GC-MS for the biodiesel samples obtained in Brazil. A cytotoxicity assay and cytokine secretion experiments were evaluated in human bronchial epithelial cells (BEAS-2B). Cells were exposed to polar (acetone) and nonpolar (hexane) extracts from particles obtained from fuel exhaust: fossil diesel (B5), pure soybean biodiesel (B100), soybean biodiesel with additive (B100A) and ethanol additive (EtOH). Biodiesel and its additives exhibited higher organic and inorganic constituents on particles when compared to B5. The biodiesel extracts did not exert any toxic effect at concentrations 10, 25, 50, 75, and 100μgmL(-1). In fact quite the opposite, a cell proliferation effect induced by the B100 and B100A extracts is reported. A small increase in concentrations of inflammatory mediators (Interleukin-6, IL-6; and Interleukin-8, IL-8) in the medium of biodiesel-treated cells was observed, however, no statistical difference was found. An interesting finding indicates that the presence of metals in the nonpolar (hexane) fraction of biodiesel fuel (B100) represses cytokine release in lung cells. This was revealed by the use of the metal chelator. Results suggest that metals associated with biodiesel's organic constituents might play a significant role in molecular mechanisms associated to cellular proliferation and immune responses.

  12. Bruceantin inhibits multiple myeloma cancer stem cell proliferation.

    PubMed

    Issa, Mark E; Berndt, Sarah; Carpentier, Gilles; Pezzuto, John M; Cuendet, Muriel

    2016-09-01

    Multiple myeloma (MM) continues to claim the lives of a majority of patients. MM cancer stem cells (CSCs) have been demonstrated to sustain tumor growth. Due to their ability to self-renew and to express detoxifying enzymes and efflux transporters, MM-CSCs are rendered highly resistant to conventional therapies. Therefore, managing MM-CSCs characteristics could have profound clinical implications. Bruceantin (BCT) is a natural product previously demonstrated to inhibit the growth of MM in RPMI 8226 cells-inoculated mouse xenograft models, and to cause regression in already established tumors. The objectives of the present study were to test the inhibitory effects of BCT on MM-CSCs growth derived from a human primary tumor, and to explore a mechanism of action underlying these effects. BCT exhibited potent antiproliferative activity in MM-CSCs starting at 25 nM. BCT induced cell cycle arrest, cell death and apoptosis in MM-CSCs as well as inhibited cell migration and angiogenesis in vitro. Using a qPCR screen, it was found that the gene expression of a number of Notch pathway members was altered. Pretreatment of MM-CSCs with the γ-secretase inhibitor RO4929097, a Notch pathway inhibitor, reversed BCT-induced effects on MM-CSCs proliferation. In this study, BCT was shown to be an effective agent in controlling the proliferation, viability and migration of MM-CSCs as well as angiogenesis in vitro. The effect on MM-CSCs proliferation may be mediated by the Notch pathway. These results warrant further investigation of BCT in a broader set of human-derived MM-CSCs and with in vivo models representative of MM.

  13. Effect of a hot water extract of Chlorella vulgaris on proliferation of IEC-6 cells.

    PubMed

    Song, Seo-Hyeon; Kim, In-Hye; Nam, Taek-Jeong

    2012-05-01

    Chlorella vulgaris, a unicellular microalgae, exerts various biological effects; however their effect on proliferation signaling pathways in normal cells has not been studied. We investigated the effect of hot water extracts of Chlorella vulgaris (CVE) on cell proliferation and related signaling pathways in rat intestinal epithelial cells (IEC-6). CVE increased the expression of insulin-like growth factor-I receptor (IGF-IR) and the phosphorylation of focal adhesion kinase (FAK) and Src. In addition, CVE induced activation of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K)/Akt pathways. We verified the increased phosphorylation of extracellular-signal-related kinase (ERK) and Akt and the increased expression of the PI3K regulatory subunit p85. CVE also influenced the canonical Wnt pathway through increased expression of the nuclear β-catenin, cyclin D1. Tyr-397 of FAK mediates interactions with Src homology 2 (SH2) domains in a number of other signaling proteins, including PI3K, PLC-γ, Shc, Grb7, Src and Nck2. Because CVE induced FAK activation, FAK may affect the Wnt pathway. Addition of a FAK inhibitor decreased the expression of nuclear β-catenin, cyclin D1 and c-myc, and increased the expression of cytosolic β-catenin. We conclude that CVE stimulated proliferation of IEC-6 cells via the MAPK, PI3K/Akt and canonical Wnt pathways, and that this affected the canonical Wnt pathway.

  14. Nitric oxide inhibits irreversibly P815 cell proliferation: involvement of potassium channels.

    PubMed

    Costa, R S A; Assreuy, J

    2002-12-01

    Nitric oxide (NO) has been shown to inhibit both normal and cancer cell proliferation. Potassium channels are involved in cell proliferation and, as NO activates these channels, we investigated the effect of NO on the proliferation of murine mastocytoma cell lines and the putative involvement of potassium channels. NO (in the form of NO donors) caused dose-dependent inhibition of cell proliferation in the P815 cell line inducing growth arrest in the mitosis phase. Incubation with NO donor for 4 or 24 h had a similar inhibitory effect on cell proliferation, indicating that this effect is irreversible. The inhibitory effect of NO was completely prevented by the blockade of voltage- and calcium-dependent potassium channels, but not by blockade of ATP-dependent channels. NO inhibition of cell proliferation was unaffected by guanylate cyclase and by cytoskeleton disruptors. Therefore, NO inhibits cell proliferation irreversibly via a potassium channel-dependent but guanylate cyclase-independent pathway in murine mastocytoma cells.

  15. Cell proliferation contributes to PNEC hyperplasia after acute airway injury.

    PubMed

    Stevens, T P; McBride, J T; Peake, J L; Pinkerton, K E; Stripp, B R

    1997-03-01

    Pulmonary neuroendocrine cells (PNECs) are airway epithelial cells that are capable of secreting a variety of neuropeptides. PNECs are scattered throughout the bronchial tree either as individual cells or clusters of cells termed neuroepithelial bodies (NEBs). PNECs and their secretory peptides have been considered to play a role in fetal lung development. Although the normal physiological function of PNECs and neuropeptides in normal adult lungs and in repair from lung injury is not known, PNEC hyperplasia has been associated with chronic lung diseases, such as bronchopulmonary dysplasia, and with chronic exposures, such as hypoxia, tobacco smoke, nitrosamines, and ozone. To evaluate changes in PNEC number and distribution after acute airway injury, FVB/n mice were treated with either naphthalene or vehicle. Naphthalene is an aromatic hydrocarbon that, at the dose used in this study, selectively destroys nonciliated bronchial epithelial cells (Clara cells) through cytochrome P-450-mediated metabolic activation into cytotoxic epoxides. PNECs were identified by immunohistochemical analysis of calcitonin gene-related peptide-like immunoreactivity (CGRP-IR). Proliferating cells were marked with [(3)H]thymidine incorporation. Acute naphthalene toxicity results in PNEC hyperplasia that is detectable after 5 days of recovery. PNEC hyperplasia is characterized by increased numbers of NEBs without significant changes in the number of isolated PNECs and by increased [(3)H]thymidine labeling of CGRP-IR cells. These data show that cell proliferation contributes to PNEC hyperplasia after acute airway injury and suggest that PNECs may be capable of more rapidly increasing their number in response to injury than previously recognized.

  16. Effects of biosurfactants on the viability and proliferation of human breast cancer cells.

    PubMed

    Duarte, Cristina; Gudiña, Eduardo J; Lima, Cristovao F; Rodrigues, Ligia R

    2014-01-01

    Biosurfactants are molecules with surface activity produced by microorganisms that can be used in many biomedical applications. The anti-tumour potential of these molecules is being studied, although results are still scarce and few data are available regarding the mechanisms underlying such activity. In this work, the anti-tumour activity of a surfactin produced by Bacillus subtilis 573 and a glycoprotein (BioEG) produced by Lactobacillus paracasei subsp. paracasei A20 was evaluated. Both biosurfactants were tested against two breast cancer cell lines, T47D and MDA-MB-231, and a non-tumour fibroblast cell line (MC-3 T3-E1), specifically regarding cell viability and proliferation. Surfactin was found to decrease viability of both breast cancer cell lines studied. A 24 h exposure to 0.05 g l(-1) surfactin led to inhibition of cell proliferation as shown by cell cycle arrest at G1 phase. Similarly, exposure of cells to 0.15 g l(-1) BioEG for 48 h decreased cancer cells' viability, without affecting normal fibroblasts. Moreover, BioEG induced the cell cycle arrest at G1 for both breast cancer cell lines. The biosurfactant BioEG was shown to be more active than surfactin against the studied breast cancer cells. The results gathered in this work are very promising regarding the biosurfactants potential for breast cancer treatment and encourage further work with the BioEG glycoprotein.

  17. TORC1 is required to balance cell proliferation and cell death in planarians.

    PubMed

    Tu, Kimberly C; Pearson, Bret J; Sánchez Alvarado, Alejandro

    2012-05-15

    Multicellular organisms are equipped with cellular mechanisms that enable them to replace differentiated cells lost to normal physiological turnover, injury, and for some such as planarians, even amputation. This process of tissue homeostasis is generally mediated by adult stem cells (ASCs), tissue-specific stem cells responsible for maintaining anatomical form and function. To do so, ASCs must modulate the balance between cell proliferation, i.e. in response to nutrients, and that of cell death, i.e. in response to starvation or injury. But how these two antagonistic processes are coordinated remains unclear. Here, we explore the role of the core components of the TOR pathway during planarian tissue homeostasis and regeneration and identified an essential function for TORC1 in these two processes. RNAi-mediated silencing of TOR in intact animals resulted in a significant increase in cell death, whereas stem cell proliferation and stem cell maintenance were unaffected. Amputated animals failed to increase stem cell proliferation after wounding and displayed defects in tissue remodeling. Together, our findings suggest two distinct roles for TORC1 in planarians. TORC1 is required to modulate the balance between cell proliferation and cell death during normal cell turnover and in response to nutrients. In addition, it is required to initiate appropriate stem cell proliferation during regeneration and for proper tissue remodeling to occur to maintain scale and proportion.

  18. Herbal Extracts Induce Dermal Papilla Cell Proliferation of Human Hair Follicles

    PubMed Central

    Rastegar, Hosein; Aghaei, Mahmoud; Barikbin, Behrooz; Ehsani, Amirohushang

    2015-01-01

    Background The number of people suffering from balding or hair thinning is increasing, despite the advances in various medical therapies. Therefore, it is highly important to develop new therapies to inhibit balding and increase hair proliferation. Objective We investigated the effects of herbal extracts commonly used for improving balding in traditional medicine to identify potential agents for hair proliferation. Methods The expression levels of 5α-reductase isoforms (type I and II) were analyzed using quantitative real-time reverse transcription polymerase chain reaction in the human follicular dermal papilla cells (DPCs). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylteterazolium bromide and bromodeoxyuridine tests were used to evaluate the cell proliferation effect of herbal extracts in DPCs. The expression levels of extracellular signal-regulated kinase (ERK), Akt, cyclin D1, cyclin-dependent kinase 4 (Cdk4), B-cell lymphoma (Bcl-2) and Bcl-2-associated X protein (Bax) were measured using western blot analysis. Results The 5α-reductase isoform mRNAs and proteins were detected in the cultured DPCs, and the expression level of 5α-R2 in DPCs in the presence of the herbal extracts was gradually decreased. Herbal extracts were found to significantly increase the proliferation of human DPCs at concentrations ranging from 1.5% to 4.5%. These results show that the herbal extracts tested affected the protein expressions of ERK, Akt, cyclin D1, Cdk4, Bcl-2, and Bax in DPCs. Conclusion These results suggest that herbal extracts exert positive effects on hair proliferation via ERK, Akt, cyclin D1, and Cdk4 signaling in DPCs; they also suggest that herbal extracts could be a great alternative therapy for increasing hair proliferation. PMID:26719634

  19. ESR1 inhibits hCG-induced steroidogenesis and proliferation of progenitor Leydig cells in mice

    PubMed Central

    Oh, Yeong Seok; Koh, Il Kyoo; Choi, Bomi; Gye, Myung Chan

    2017-01-01

    Oestrogen is an important regulator in reproduction. To understand the role of oestrogen receptor 1 (ESR1) in Leydig cells, we investigated the expression of ESR1 in mouse Leydig cells during postnatal development and the effects of oestrogen on steroidogenesis and proliferation of progenitor Leydig cells (PLCs). In Leydig cells, the ESR1 expression was low at birth, increased until postnatal day 14 at which PLCs were predominant, and then decreased until adulthood. In foetal Leydig cells, ESR1 immunoreactivity increased from birth to postnatal day 14. These suggest that ESR1 is a potential biomarker of Leydig cell development. In PLCs, 17β-estradiol and the ESR1-selective agonist propylpyrazoletriol suppressed human chorionic gonadotropin (hCG)-induced progesterone production and steroidogenic gene expression. The ESR2-selective agonist diarylpropionitrile did not affect steroidogenesis. In PLCs from Esr1 knockout mice, hCG-stimulated steroidogenesis was not suppressed by 17β-estradiol, suggesting that oestrogen inhibits PLC steroidogenesis via ESR1. 17β-estradiol, propylpyrazoletriol, and diarylpropionitrile decreased bromodeoxyuridine uptake in PLCs in the neonatal mice. In cultured PLCs, 17β-estradiol, propylpyrazoletriol, and diarylpropionitrile reduced hCG-stimulated Ki67 and Pcna mRNA expression and the number of KI67-positive PLCs, suggesting that oestrogen inhibits PLC proliferation via both ESR1 and ESR2. In PLCs, ESR1 mediates the oestrogen-induced negative regulation of steroidogenesis and proliferation. PMID:28266530

  20. p62 Regulates the Proliferation of Molecular Apocrine Breast Cancer Cells

    PubMed Central

    Nozaki, Fumi; Hirotani, Yukari; Nakanishi, Yoko; Yamaguchi, Hiromi; Nishimaki, Haruna; Noda, Hiroko; Tang, Xiaoyan; Yamamoto, Hisae; Suzuki, Atsuko; Seki, Toshimi; Masuda, Shinobu

    2016-01-01

    p62, also called sequestosome 1 (SQSTM1), is a multifunctional signaling molecule that affects cell proliferation. Recently, we found accumulation of p62 in apocrine carcinoma of the breast, however, the biological role of p62 expression in apocrine carcinoma still remains unclear. To investigate whether p62 might contribute to tumor cell proliferation in apocrine carcinomas, we used the MDA-MB-453 (androgen receptor-positive, HER2-type) and MFM223 (androgen receptor-positive, triple-negative type) breast cancer cell lines as models of molecular apocrine carcinoma. Both MDA-MB-453 and MFM223 showed strong and d high p62 protein expression than MCF7 cells (androgen receptor-negative, luminal A type). Knockdown of p62 resulted in significant reduction of the cell proliferative activity in both MDA-MB-453 (P<0.01) and MFM223 (P<0.05). In conclusion, p62 could contribute to cell proliferation and represent a therapeutic target in apocrine carcinoma. PMID:27682016

  1. Neural progenitors organize in small-world networks to promote cell proliferation.

    PubMed

    Malmersjö, Seth; Rebellato, Paola; Smedler, Erik; Planert, Henrike; Kanatani, Shigeaki; Liste, Isabel; Nanou, Evanthia; Sunner, Hampus; Abdelhady, Shaimaa; Zhang, Songbai; Andäng, Michael; El Manira, Abdeljabbar; Silberberg, Gilad; Arenas, Ernest; Uhlén, Per

    2013-04-16

    Coherent network activity among assemblies of interconnected cells is essential for diverse functions in the adult brain. However, cellular networks before formations of chemical synapses are poorly understood. Here, embryonic stem cell-derived neural progenitors were found to form networks exhibiting synchronous calcium ion (Ca(2+)) activity that stimulated cell proliferation. Immature neural cells established circuits that propagated electrical signals between neighboring cells, thereby activating voltage-gated Ca(2+) channels that triggered Ca(2+) oscillations. These network circuits were dependent on gap junctions, because blocking prevented electrotonic transmission both in vitro and in vivo. Inhibiting connexin 43 gap junctions abolished network activity, suppressed proliferation, and affected embryonic cortical layer formation. Cross-correlation analysis revealed highly correlated Ca(2+) activities in small-world networks that followed a scale-free topology. Graph theory predicts that such network designs are effective for biological systems. Taken together, these results demonstrate that immature cells in the developing brain organize in small-world networks that critically regulate neural progenitor proliferation.

  2. Proliferation rates of bovine primary muscle cells relate to liveweight and carcase weight in cattle.

    PubMed

    Coles, Chantal A; Wadeson, Jenny; Leyton, Carolina P; Siddell, Jason P; Greenwood, Paul L; White, Jason D; McDonagh, Matthew B

    2015-01-01

    Muscling in cattle is largely influenced by genetic background, ultimately affecting beef yield and is of major interest to the beef industry. This investigation aimed to determine whether primary skeletal muscle cells isolated from different breeds of cattle with a varying genetic potential for muscling differ in their myogenic proliferative capacity. Primary skeletal muscle cells were isolated and cultured from the Longissimus muscle (LM) of 6 month old Angus, Hereford and Wagyu X Angus cattle. Cells were assessed for rate of proliferation and gene expression of PAX7, MYOD, MYF5, and MYOG. Proliferation rates were found to differ between breeds of cattle whereby myoblasts from Angus cattle were found to proliferate at a greater rate than those of Hereford and Wagyu X Angus during early stages of growth (5-20 hours in culture) in vitro (P < 0.05). The proliferation rates of myoblasts during early stages of culture in vitro were also found to be positively related to the liveweight and carcase weight of cattle (P < 0.05). Gene expression of MYF5 was also found to be significantly down-regulated in WagyuX compared with Angus cattle (P < 0.05). These findings suggest that early events during myogenesis are important for determining liveweight and caracase weights in cattle.

  3. Effects of aging on mouse tongue epithelium focusing on cell proliferation rate and morphological aspects.

    PubMed

    Carrard, Vinicius Coelho; Pires, Aline Segatto; Badauy, Cristiano Macabu; Rados, Pantelis Varvaki; Lauxen, Isabel Silva; Sant'Ana Filho, Manoel

    2008-11-01

    The aim of this study was to investigate cell proliferation rate and certain morphological features of mouse epithelium as aging progresses. Tongue biopsies were performed on female mice (Mus domesticus domesticus) at 2, 8, 14 and 20 months of age as indicative of adolescence, adulthood, early senescence and senescence, respectively. Histological sections of tongue were stained with hematoxylin-eosin and subjected to silver staining for active nucleolar organizer region counting. Cell proliferation rate and epithelial thickness analysis were carried out. Analysis of variance detected no differences between the groups in terms of numbers of silver-stained dots associated with nucleolar proteins. There was an increase in mean epithelial thickness in adult animals, followed by a gradual reduction until senescence. Mean keratin thickness presented an increase at 8 and 20 months of age. This difference is probably related to puberty, growth or dietary habits. Aging has no influence on oral epithelial proliferation rate in mice. A gradual reduction in epithelial thickness is a feature of aging in mammals. A conspicuous increase in the keratin layer was observed in senescence as an adaptative response to the reduction in epithelial thickness. These results suggest that aging affects the oral epithelium maturation process through a mechanism that is not related to cell proliferation.

  4. Proliferation Rates of Bovine Primary Muscle Cells Relate to Liveweight and Carcase Weight in Cattle

    PubMed Central

    Coles, Chantal A.; Wadeson, Jenny; Leyton, Carolina P.; Siddell, Jason P.; Greenwood, Paul L.; White, Jason D.; McDonagh, Matthew B.

    2015-01-01

    Muscling in cattle is largely influenced by genetic background, ultimately affecting beef yield and is of major interest to the beef industry. This investigation aimed to determine whether primary skeletal muscle cells isolated from different breeds of cattle with a varying genetic potential for muscling differ in their myogenic proliferative capacity. Primary skeletal muscle cells were isolated and cultured from the Longissimus muscle (LM) of 6 month old Angus, Hereford and Wagyu X Angus cattle. Cells were assessed for rate of proliferation and gene expression of PAX7, MYOD, MYF5, and MYOG. Proliferation rates were found to differ between breeds of cattle whereby myoblasts from Angus cattle were found to proliferate at a greater rate than those of Hereford and Wagyu X Angus during early stages of growth (5–20 hours in culture) in vitro (P < 0.05). The proliferation rates of myoblasts during early stages of culture in vitro were also found to be positively related to the liveweight and carcase weight of cattle (P < 0.05). Gene expression of MYF5 was also found to be significantly down-regulated in WagyuX compared with Angus cattle (P < 0.05). These findings suggest that early events during myogenesis are important for determining liveweight and caracase weights in cattle. PMID:25875203

  5. Telomere-interactive agents affect proliferation rates and induce chromosomal destabilization in sea urchin embryos.

    PubMed

    Izbicka, E; Nishioka, D; Marcell, V; Raymond, E; Davidson, K K; Lawrence, R A; Wheelhouse, R T; Hurley, L H; Wu, R S; Von Hoff, D D

    1999-08-01

    Cationic porphyrins, which interact with guanine quadruplex (G4) telomeric folds, inhibit telomerase activity in human tumor cells. In this study, we have further examined effects of porphyrins and other telomere- and telomerase-interactive agents on proliferation rates and chromosome stability in a novel in vivo model, developing sea urchin embryos. We studied two porphyrins: (i) TMPyP4, a potent telomerase inhibitor; and (ii) TMPyP2, an isomer of TMPyP4 and an inefficient telomerase inhibitor, azidothymine (AZT), the reverse transcriptase inhibitor, antisense phosphorothioate oligonucleotide to telomerase RNA (TAG6) and a control scrambled sequence (ODN). TMPyP4, AZT and TAG6 (but not TMPyP2 or ODN) decreased the rates of cell proliferation and increased the percentage of cells trapped in mitosis. Nuclear localization of TAG6, but not of ODN, was demonstrated with 5'-fluoresceinated analogs of TAG6 and ODN. Formation of elongated chromosomes incapable of separating in anaphase, induced by TMPyP4, AZT and TAG6, closely resembled phenotypes resulting from telomerase template mutation or dominant negative TRF2 allele. Our data suggest that G4-interactive agents exert their antiproliferative effects via chromosomal destabilization and warrant their further development as valuable anticancer tools.

  6. Astaxanthin Inhibits Proliferation and Induces Apoptosis and Cell Cycle Arrest of Mice H22 Hepatoma Cells

    PubMed Central

    Shao, Yiye; Ni, Yanbo; Yang, Jing; Lin, Xutao; Li, Jun; Zhang, Lixia

    2016-01-01

    Background It is widely recognized that astaxanthin (ASX), a member of the carotenoid family, has strong biological activities including antioxidant, anti-inflammation, and immune-modulation activities. Previous studies have confirmed that ASX can effectively inhibit hepatoma cells in vitro. Material/Methods MTT was used to assay proliferation of mice H22 cells, and flow cytometry was used to determine apoptosis and cell cycle arrest of H22 cells in vitro and in vivo. Moreover, anti-tumor activity of ASX was observed in mice. Results ASX inhibited the proliferation of H22 cells, promoted cell necrosis, and induced cell cycle arrest in G2 phase in vitro and in vivo. Conclusions This study indicated that ASX can inhibit proliferation and induce apoptosis and cell cycle arrest in mice H22 hepatoma cells in vitro and in vivo. PMID:27333866

  7. Induction of proliferation in vitro of resting human natural killer cells

    SciTech Connect

    London, L.

    1986-01-01

    Experiments examined the cellular and humoral factors necessary to induce proliferation of purified NK cells in vitro and analyzed the phenotypic characteristics of these proliferating cells. The authors experiments demonstrated that NK cells do not proliferate in response to typical T cell mitogens or to allogeneic stimulation. However, NK cells are readily induced to proliferate in response to either natural or recombinant IL-2. The proliferative response of NK cells to IL-2 is enhanced in the presence of irradiated B lymphoblastoid ell lines. Proliferating NK cells maintain the expression of surface markers characteristic of freshly isolated NK cells which newly expressing surface activation antigens including the IL-2 and transferric receptors and the HLA-DR antigen. The majority of NK cells initiate proliferation in response to IL-2. Greater than 50 U/ml of IL-2 is necessary to induce maximal tritiated thymidine (/sup 3/H-TdR) incorporation by NK cells, and the interaction of IL-2 with the Tac IL-2 receptor is required for the maintenance of NK cell proliferation. NK cells do not proliferate in response to irradiated Daudi cells alone, which, in the presence of IL-2, may act by maintaining continuous proliferation of the cells originally responsive to IL-2. Unlike NK cells, the authors have shown that only a minor subset of T cells proliferate in response to IL-2 alone.

  8. Conditional telomerase induction causes proliferation of hair follicle stem cells

    PubMed Central

    Sarin, Kavita Y.; Cheung, Peggie; Gilison, Daniel; Lee, Eunice; Tennen, Ruth I.; Wang, Estee; Artandi, Maja K.; Oro, Anthony E.; Artandi, Steven E.

    2005-01-01

    TERT, the protein component of telomerase1,2, serves to maintain telomere function through the de novo addition of telomere repeats to chromosome ends and is reactivated in 90% of human cancers. In normal tissues, TERT is expressed in stem cells and in progenitor cells3, but its role in these compartments is not fully understood. Here, we show that conditional transgenic induction of TERT in mouse skin epithelium causes a rapid transition from telogen, the resting phase of the hair follicle cycle, to anagen, the active phase, thereby facilitating robust hair growth. TERT overexpression promotes this developmental transition by causing proliferation of quiescent, multipotent stem cells in the hair follicle bulge region. This new function for TERT does not require the telomerase RNA component (TERC), which encodes the template for telomere addition, and therefore operates through a novel mechanism independent of its activity in synthesizing telomere repeats. These data indicate that, in addition to its established role in extending telomeres, TERT can promote proliferation of resting stem cells through a non-canonical pathway. PMID:16107853

  9. Unremitting Cell Proliferation in the Secretory Phase of Eutopic Endometriosis

    PubMed Central

    Franco-Murillo, Yanira; Miranda-Rodríguez, José Antonio; Rendón-Huerta, Erika; Montaño, Luis F.; Cornejo, Gerardo Velázquez; Gómez, Lucila Poblano; Valdez-Morales, Francisco Javier; Gonzalez-Sanchez, Ignacio

    2014-01-01

    Objective: Endometriosis is linked to altered cell proliferation and stem cell markers c-kit/stem cell factor (SCF) in ectopic endometrium. Our aim was to investigate whether c-kit/SCF also plays a role in eutopic endometrium. Design: Eutopic endometrium obtained from 35 women with endometriosis and 25 fertile eumenorrheic women was analyzed for in situ expression of SCF/c-kit, Ki67, RAC-alpha serine/threonine-protein kinase (Akt), phosphorylated RAC-alpha serine/threonin-protein kinase (pAkt), Glycogen synthase kinase 3 beta (GSK3β), and phosphorylated glycogen synthase kinase 3 beta (pGSK3β), throughout the menstrual cycle. Results: Expression of Ki67 and SCF was higher in endometriosis than in control tissue (P < .05) and greater in secretory rather than proliferative (P < .01) endometrium in endometriosis. Expression of c-kit was also higher in endometriosis although similar in both phases. Expression of Akt and GSK3β was identical in all samples and cycle phases, whereas pAkt and pGSK3β, opposed to control tissue, remained overexpressed in the secretory phase in endometriosis. Conclusion: Unceasing cell proliferation in the secretory phase of eutopic endometriosis is linked to deregulation of c-kit/SCF-associated signaling pathways. PMID:25194152

  10. Lysyl oxidase propeptide inhibits smooth muscle cell signaling and proliferation

    SciTech Connect

    Hurtado, Paola A.; Vora, Siddharth; Sume, Siddika Selva; Yang, Dan; Hilaire, Cynthia St.; Guo Ying; Palamakumbura, Amitha H.; Schreiber, Barbara M.; Ravid, Katya; Trackman, Philip C.

    2008-02-01

    Lysyl oxidase is required for the normal biosynthesis and maturation of collagen and elastin. It is expressed by vascular smooth muscle cells, and its increased expression has been previously found in atherosclerosis and in models of balloon angioplasty. The lysyl oxidase propeptide (LOX-PP) has more recently been found to have biological activity as a tumor suppressor, and it inhibits Erk1/2 Map kinase activation. We reasoned that LOX-PP may have functions in normal non-transformed cells. We, therefore, investigated its effects on smooth muscle cells, focusing on important biological processes mediated by Erk1/2-dependent signaling pathways including proliferation and matrix metalloproteinase-9 (MMP-9) expression. In addition, we investigated whether evidence for accumulation of LOX-PP could be found in vivo in a femoral artery injury model. Recombinant LOX-PP was expressed and purified, and was found to inhibit primary rat aorta smooth muscle cell proliferation and DNA synthesis by more than 50%. TNF-{alpha}-stimulated MMP-9 expression and Erk1/2 activation were both significantly inhibited by LOX-PP. Immunohistochemistry studies carried out with affinity purified anti-LOX-PP antibody showed that LOX-PP epitopes were expressed at elevated levels in vascular lesions of injured arteries. These novel data suggest that LOX-PP may provide a feedback control mechanism that serves to inhibit properties associated with the development of vascular pathology.

  11. NAP reduces murine microvascular endothelial cells proliferation induced by hyperglycemia.

    PubMed

    D'Amico, Agata Grazia; Scuderi, Soraya; Maugeri, Grazia; Cavallaro, Sebastiano; Drago, Filippo; D'Agata, Velia

    2014-11-01

    Hyperglycemia has been identified as a risk factor responsible for micro- and macrovascular complications in diabetes. NAP (Davunetide) is a peptide whose neuroprotective actions are widely demonstrated, although its biological role on endothelial dysfunctions induced by hyperglycemia remains uninvestigated. In the present study we hypothesized that NAP could play a protective role on hyperglycemia-induced endothelial cell proliferation. To this end we investigated the effects of NAP on an in vitro model of murine microvascular endothelial cells grown in high glucose for 7 days. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay and cyclin D1 protein expression analysis revealed that NAP treatment significantly reduces viability and proliferation of the cells. Hyperglycemia induced the activation of mitogen-activated protein kinase/extracellular signal-regulated protein kinase and/or phosphatidylinositol-3 kinase/Akt pathways in a time-dependent manner. NAP treatment reduced the phosphorylation levels of ERK and AKT in cells grown in high glucose. These evidences suggest that NAP might be effective in the regulation of endothelial dysfunction induced by hyperglycemia.

  12. Toll-like receptor signaling in cell proliferation and survival

    PubMed Central

    Li, Xinyan; Jiang, Song; Tapping, Richard I.

    2009-01-01

    Toll-like receptors (TLRs) are important sensors of foreign microbial components as well as products of damaged or inflamed self tissues. Upon sensing these molecules, TLRs initiate a series of downstream signaling events that drive cellular responses including the production of cytokines, chemokines and other inflammatory mediators. This outcome results from the intracellular assembly of protein complexes that drive phosphorylation and other signaling cascades ultimately leading to chromatin remodeling and transcription factor activation. In addition to driving inflammatory responses, TLRs also regulate cell proliferation and survival which serves to expand useful immune cells and integrate inflammatory responses and tissue repair processes. In this context, central TLR signaling molecules, such as the mitogen-activated protein kinases (MAPK) and phosphoinositide 3-kinase (PI3K), play key roles. In addition, four major groups of transcription factors which are targets of TLR activation also control cell fate. This review focuses on the role of TLR signaling as it relates to cell proliferation and survival. This topic not only has important implications for understanding host defense and tissue repair, but also cancer which is often associated with conditions of chronic inflammation. PMID:19775907

  13. Maternal thyroid hormone deficiency affects the fetal neocorticogenesis by reducing the proliferating pool, rate of neurogenesis and indirect neurogenesis.

    PubMed

    Mohan, Vishwa; Sinha, Rohit A; Pathak, Amrita; Rastogi, Leena; Kumar, Praveen; Pal, Amit; Godbole, Madan M

    2012-10-01

    Neuronal progenitor cell proliferation and their optimum number are indispensable for neurogenesis, which is determined by cell cycle length and cell cycle quitting rate of the dividing progenitors. These processes are tightly orchestrated by transcription factors like Tbr2, Pax6, and E2f-1. Radial glia and intermediate progenitor cells (IPC) through direct and indirect neurogenesis maintain surface area and neocortical thickness during development. Here we show that fetal neurogenesis is maternal thyroid hormone (MTH) dependent with differential effect on direct and indirect neurogenesis. MTH deficiency (MTHD) impairs direct neurogenesis through initial down-regulation of Pax6 and diminished progenitor pool with recovery even before the onset of fetal thyroid function (FTF). However, persistent decrease in Tbr2 positive IPCs, diminished NeuN positivity in layers I-III of neocortex, and reduced cortical thickness indicate a non-compensatory impairment in indirect neurogenesis. TH deficiency causes disrupted cell cycle kinetics and deranged neurogenesis. It specifically affects indirect neurogenesis governed by intermediate progenitor cells (IPCs). TH replacement in hypothyroid dams partially restored the rate of neurogenesis in the fetal neocortex. Taken together we describe a novel role of maternal TH in promoting IPCs derived neuronal differentiation in developing neo-cortex. We have also shown for the first time that ventricular zone progenitors are TH responsive as they express its receptor, TR alpha-1, transporters (MCT8) and deiodinases. This study highlights the importance of maternal thyroid hormone (TH) even before the start of the fetal thyroid function.

  14. Exosomes Secreted by Toxoplasma gondii-Infected L6 Cells: Their Effects on Host Cell Proliferation and Cell Cycle Changes.

    PubMed

    Kim, Min Jae; Jung, Bong-Kwang; Cho, Jaeeun; Song, Hyemi; Pyo, Kyung-Ho; Lee, Ji Min; Kim, Min-Kyung; Chai, Jong-Yil

    2016-04-01

    Toxoplasma gondii infection induces alteration of the host cell cycle and cell proliferation. These changes are not only seen in directly invaded host cells but also in neighboring cells. We tried to identify whether this alteration can be mediated by exosomes secreted by T. gondii-infected host cells. L6 cells, a rat myoblast cell line, and RH strain of T. gondii were selected for this study. L6 cells were infected with or without T. gondii to isolate exosomes. The cellular growth patterns were identified by cell counting with trypan blue under confocal microscopy, and cell cycle changes were investigated by flow cytometry. L6 cells infected with T. gondii showed decreased proliferation compared to uninfected L6 cells and revealed a tendency to stay at S or G2/M cell phase. The treatment of exosomes isolated from T. gondii-infected cells showed attenuation of cell proliferation and slight enhancement of S phase in L6 cells. The cell cycle alteration was not as obvious as reduction of the cell proliferation by the exosome treatment. These changes were transient and disappeared at 48 hr after the exosome treatment. Microarray analysis and web-based tools indicated that various exosomal miRNAs were crucial for the regulation of target genes related to cell proliferation. Collectively, our study demonstrated that the exosomes originating from T. gondii could change the host cell proliferation and alter the host cell cycle.

  15. A simple non-perturbing cell migration assay insensitive to proliferation effects.

    PubMed

    Glenn, Honor L; Messner, Jacob; Meldrum, Deirdre R

    2016-08-18

    Migration is a fundamental cellular behavior that plays an indispensable role in development and homeostasis, but can also contribute to pathology such as cancer metastasis. Due to its relevance to many aspects of human health, the ability to accurately measure cell migration is of broad interest, and numerous approaches have been developed. One of the most commonly employed approaches, because of its simplicity and throughput, is the exclusion zone assay in which cells are allowed to migrate into an initially cell-free region. A major drawback of this assay is that it relies on simply counting cells in the exclusion zone and therefore cannot distinguish the effects of proliferation from migration. We report here a simple modification to the exclusion zone migration assay that exclusively measures cell migration and is not affected by proliferation. This approach makes use of a lineage-tracing vital stain that is retained through cell generations and effectively reads out migration relative to the original, parental cell population. This modification is simple, robust, non-perturbing, and inexpensive. We validate the method in a panel of cell lines under conditions that inhibit or promote migration and demonstrate its use in normal and cancer cell lines as well as primary cells.

  16. Histone H3 Glutathionylation in Proliferating Mammalian Cells Destabilizes Nucleosomal Structure

    PubMed Central

    Olaso, Gloria; Hake, Sandra B.; Bönisch, Clemens; Wiedemann, Sonja M.; Markovic, Jelena; Dasí, Francisco; Gimeno, Amparo; Pérez-Quilis, Carme; Palacios, Òscar; Capdevila, Mercè; Viña, José

    2013-01-01

    Abstract Aims: Here we report that chromatin, the complex and dynamic eukaryotic DNA packaging structure, is able to sense cellular redox changes. Histone H3, the only nucleosomal protein that possesses cysteine(s), can be modified by glutathione (GSH). Results: Using Biotin labeled glutathione ethyl ester (BioGEE) treatment of nucleosomes in vitro, we show that GSH, the most abundant antioxidant in mammals, binds to histone H3. BioGEE treatment of NIH3T3 cells indicates that glutathionylation of H3 is maximal in fast proliferating cells, correlating well with enhanced levels of H3 glutathionylation in different tumor cell lines. Furthermore, glutathionylation of H3 in vivo decreases in livers from aged SAMP8 and C57BL/6J mice. We demonstrate biochemically and by mass spectrometry that histone variants H3.2/H3.3 are glutathionylated on their cysteine residue 110. Furthermore, circular dichroism, thermal denaturation of reconstituted nucleosomes, and molecular modeling indicate that glutathionylation of histone H3 produces structural changes affecting nucleosomal stability. Innovation: We characterize the implications of histone H3 glutathionylation in cell physiology and the modulation of core histone proteins structure affected by this modification. Conclusion: Histone H3 senses cellular redox changes through glutathionylation of Cys, which increases during cell proliferation and decreases during aging. Glutathionylation of histone H3 affects nucleosome stability structure leading to a more open chromatin structure. Antioxid. Redox Signal. 19, 1305–1320. PMID:23541030

  17. SIRT1 controls cell proliferation by regulating contact inhibition.

    PubMed

    Cho, Elizabeth H; Dai, Yan

    2016-09-16

    Contact inhibition keeps cell proliferation in check and serves as a built-in protection against cancer development by arresting cell division upon cell-cell contact. Yet the complete mechanism behind this anti-cancer process remains largely unclear. Here we present SIRT1 as a novel regulator of contact inhibition. SIRT1 performs a wide variety of functions in biological processes, but its involvement in contact inhibition has not been explored to date. We used NIH3T3 cells, which are sensitive to contact inhibition, and H460 and DU145 cancer cells, which lack contact inhibition, to investigate the relationship between SIRT1 and contact inhibition. We show that SIRT1 overexpression in NIH3T3 cells overcomes contact inhibition while SIRT1 knockdown in cancer cells restores their lost contact inhibition. Moreover, we demonstrate that p27 protein expression is controlled by SIRT1 in contact inhibition. Overall, our findings underline the critical role of SIRT1 in contact inhibition and suggest SIRT1 inhibition as a potential strategy to suppress cancer cell growth by restoring contact inhibition.

  18. Inhibition of cell proliferation by the Mad1 transcriptional repressor.

    PubMed Central

    Roussel, M F; Ashmun, R A; Sherr, C J; Eisenman, R N; Ayer, D E

    1996-01-01

    Mad1 is a basic helix-loop-helix-leucine zipper protein that is induced upon differentiation of a number of distinct cell types. Mad1 dimerizes with Max and recognizes the same DNA sequences as do Myc:Max dimers. However, Mad1 and Myc appear to have opposing functions. Myc:Max heterodimers activate transcription while Mad:Max heterodimers repress transcription from the same promoter. In addition Mad1 has been shown to block the oncogenic activity of Myc. Here we show that ectopic expression of Mad1 inhibits the proliferative response of 3T3 cells to signaling through the colony-stimulating factor-1 (CSF-1) receptor. The ability of over-expressed Myc and cyclin D1 to complement the mutant CSF-1 receptor Y809F (containing a Y-to-F mutation at position 809) is also inhibited by Mad1. Cell cycle analysis of proliferating 3T3 cells transfected with Mad1 demonstrates a significant decrease in the fraction of cells in the S and G2/M phases and a concomitant increase in the fraction of G1 phase cells, indicating that Mad1 negatively influences cell cycle progression from the G1 to the S phase. Mutations in Mad1 which inhibit its activity as a transcription repressor also result in loss of Mad1 cell cycle inhibitory activity. Thus, the ability of Mad1 to inhibit cell cycle progression is tightly coupled to its function as a transcriptional repressor. PMID:8649388

  19. The effect of stem cell factor on proliferation of human endometrial CD146+ cells

    PubMed Central

    Fayazi, Mehri; Salehnia, Mojdeh; Ziaei, Saeideh

    2016-01-01

    Background: Stem cell factor (SCF) is a transcriptional factor which plays crucial roles in normal proliferation, differentiation and survival in a range of stem cells. Objective: The aim of the present study was to examine the proliferation effect of different concentrations of SCF on expansion of human endometrial CD146+ cells. Materials and Methods: In this experimental study, total populations of isolated human endometrial suspensions after fourth passage were isolated by magnetic activated cell sorting (MACS) into CD146+ cells. Human endometrial CD146+ cells were karyotyped and tested for the effect of SCF on proliferation of CD146+ cells, then different concentrations of 0, 12.5, 25, 50 and 100 ng/ml was carried out and mitogens-stimulated endometrial CD146+ cells proliferation was assessed by MTT assay. Results: Chromosomal analysis showed a normal metaphase spread and 46XX karyotype. The proliferation rate of endometrial CD146+ cells in the presence of 0, 12.5, 25, 50 and 100 ng/ml SCF were 0.945±0.094, 0.962±0.151, 0.988±0.028, 1.679±0.012 and 1.129±0.145 respectively. There was a significant increase in stem/ stromal cell proliferation following in vitro treatment by 50 ng/ml than other concentrations of SCF (p=0.01). Conclusion: The present study suggests that SCF could have effect on the proliferation and cell survival of human endometrial CD146+ cells and it has important implications for medical sciences and cell therapies. PMID:27525327

  20. Effects of iron chelators, iron salts, and iron oxide nanoparticles on the proliferation and the iron content of oligodendroglial OLN-93 cells.

    PubMed

    Hohnholt, Michaela; Geppert, Mark; Dringen, Ralf

    2010-08-01

    The oligodendroglial cell line OLN-93 was used as model system to investigate the consequences of iron deprivation or iron excess on cell proliferation. Presence of ferric or ferrous iron chelators inhibited the proliferation of OLN-93 cells in a time and concentration dependent manner, while the application of a molar excess of ferric ammonium citrate (FAC) prevented the inhibition of proliferation by the chelator deferoxamine. Proliferation of OLN-93 cells was not affected by incubation with 300 microM iron that was applied in the form of FAC, FeCl(2), ferrous ammonium sulfate or iron oxide nanoparticles, although the cells efficiently accumulated iron during exposure to each of these iron sources. The highest specific iron content was observed for cells that were exposed to the nanoparticles. These data demonstrate that the proliferation of OLN-93 cells depends strongly on the availability of iron and that these cells efficiently accumulate iron from various extracellular iron sources.

  1. EPO-independent functional EPO receptor in breast cancer enhances estrogen receptor activity and promotes cell proliferation

    SciTech Connect

    Reinbothe, Susann; Larsson, Anna-Maria; Vaapil, Marica; Wigerup, Caroline; Sun, Jianmin; Jögi, Annika; Neumann, Drorit; Rönnstrand, Lars; Påhlman, Sven

    2014-02-28

    Highlights: • New anti-human EPOR antibody confirms full-length EPOR expression in breast cancer cells. • Proliferation of breast cancer cells is not affected by rhEPO treatment in vitro. • EPOR knockdown impairs proliferation of ERa positive breast cancer cells. • EPOR knockdown reduces AKT phosphorylation and ERa activity. - Abstract: The main function of Erythropoietin (EPO) and its receptor (EPOR) is the stimulation of erythropoiesis. Recombinant human EPO (rhEPO) is therefore used to treat anemia in cancer patients. However, clinical trials have indicated that rhEPO treatment might promote tumor progression and has a negative effect on patient survival. In addition, EPOR expression has been detected in several cancer forms. Using a newly produced anti-EPOR antibody that reliably detects the full-length isoform of the EPOR we show that breast cancer tissue and cells express the EPOR protein. rhEPO stimulation of cultured EPOR expressing breast cancer cells did not result in increased proliferation, overt activation of EPOR (receptor phosphorylation) or a consistent activation of canonical EPOR signaling pathway mediators such as JAK2, STAT3, STAT5, or AKT. However, EPOR knockdown experiments suggested functional EPO receptors in estrogen receptor positive (ERα{sup +}) breast cancer cells, as reduced EPOR expression resulted in decreased proliferation. This effect on proliferation was not seen in ERα negative cells. EPOR knockdown decreased ERα activity further supports a mechanism by which EPOR affects proliferation via ERα-mediated mechanisms. We show that EPOR protein is expressed in breast cancer cells, where it appears to promote proliferation by an EPO-independent mechanism in ERα expressing breast cancer cells.

  2. Hepassocin regulates cell proliferation of the human hepatic cells L02 and hepatocarcinoma cells through different mechanisms.

    PubMed

    Cao, Meng-Meng; Xu, Wang-Xiang; Li, Chang-Yan; Cao, Chuan-Zeng; Wang, Zhi-Dong; Yao, Jia-Wei; Yu, Miao; Zhan, Yi-Qun; Wang, Xiao-Hui; Tang, Liu-Jun; Chen, Hui; Li, Wei; Ge, Chang-Hui; Yang, Xiao-Ming

    2011-10-01

    Hepassocin (HPS) is a specific mitogenic active factor for hepatocytes, and inhibits growth by overexpression in hepatocellular carcinoma (HCC) cells. However, the mechanism of HPS regulation on growth of liver-derived cells still remains largely unknown. In this study, we found that HPS was expressed and secreted into the extracellular medium in cultured L02 human hepatic cells; conditional medium of L02 cells promoted proliferation of L02 cells and this activity could be blocked by anti-HPS antibody. Moreover, we identified the presence of receptor for HPS on L02 cells and HepG2 human hepatoma cells. Overproduction of truncated HPS, which signal peptide was deleted, significantly inhibited the proliferation of HCC cells and induced cell cycle arrest. These findings suggest that HPS promotes hepatic cell line L02 cells proliferation via an autocrine mechanism and inhibits HCC cells proliferation by an intracrine pathway.

  3. Transspinal direct current stimulation modulates migration and proliferation of adult newly born spinal cells in mice.

    PubMed

    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

  4. Proliferation of hepatic stellate cells is inhibited by phosphorylation of CREB on serine 133.

    PubMed Central

    Houglum, K; Lee, K S; Chojkier, M

    1997-01-01

    Proliferating, activated, hepatic stellate cells have a high level of collagen type I expression. Therefore, stellate cell proliferation is a critical step in hepatic fibrosis. Here we show that proliferation of activated primary rat stellate cells was blocked by elevation of cAMP with 8 Br-cAMP or isomethylbutyl xanthine, a phosphodiesterase inhibitor, and by stimulation of Ca2+ fluxes with the Ca2+ ionophore A-23187. Because phosphorylation of CREB on Ser133 is an important mediator of cAMP-protein kinase (PKA) and Ca2+-calmodulin kinase II (CAMK-II) activation, we tested whether CREB-PSer133 was essential for stellate cell quiescence. Nuclear extracts from quiescent, but not from activated, stellate cells contained CREB-PSer133. Moreover, the phosphorylation of CREB on Ser133 was stimulated in activated cells by inducing the activity of PKA or CAMK-II. In addition, coexpression of CREB and either a constitutively active PKA or a constitutively active CAMK-II inhibited the proliferation of activated stellate cells. In contrast, expression of CREB alone, PKA or CAMK-II alone, CREB-Ala 133 (which lacks the Ser133 phosphoacceptor) with PKA or CAMK-II, or CREB with inactive PKA or CAMK-II mutants did not affect stellate cell proliferation, suggesting that CREB-PSer133 is necessary for blocking the stellate cell cycle. Conversely, expression of a trans-dominant negative CREB-Ala 133 mutant (which competes with CREB/CREB-PSer133 for cognate DNA binding sites and presumably for protein interactions) induced a greater than fivefold entry into S-phase of quiescent stellate cells, compared with control cells expressing either beta-galactosidase or wt CREB, indicating that CREB-PSer133 may be indispensable for the quiescent stellate cell phenotype. This study suggests that PKA and CAMK-II play an essential role on stellate cell activation through the induction of CREB phosphorylation on Ser133, and provides potential approaches for the treatment of hepatic fibrogenesis in

  5. Structural requirements for novel coenzyme-substrate derivatives to inhibit intracellular ornithine decarboxylase and cell proliferation.

    PubMed

    Wu, Fang; Gehring, Heinz

    2009-02-01

    Creating transition-state mimics has proven to be a powerful strategy in developing inhibitors to treat malignant diseases in several cases. In the present study, structurally diverse coenzyme-substrate derivatives mimicking this type for pyridoxal 5'-phosphate-dependent human ornithine decarboxylase (hODC), a potential anticancer target, were designed, synthesized, and tested to elucidate the structural requirements for optimal inhibition of intracellular ODC as well as of tumor cell proliferation. Of 23 conjugates, phosphopyridoxyl- and pyridoxyl-L-tryptophan methyl ester (pPTME, PTME) proved significantly more potent in suppression proliferation (IC(50) up to 25 microM) of glioma cells (LN229) than alpha-DL-difluoromethylornithine (DFMO), a medically used irreversible inhibitor of ODC. In agreement with molecular modeling predictions, the inhibitory action of pPTME and PTME toward intracellular ODC of LN229 cells exceeded that of the previous designed lead compound POB. The inhibitory active compounds feature hydrophobic side chain fragments and a kind of polyamine motif (-NH-(CH(X))(4)-NH-). In addition, they induce, as polyamine analogs often do, the activity of the polyamine catabolic enzymes polyamine oxidase and spermine/spermidine N(1)-acetyltransferase up to 250 and 780%, respectively. The dual-action mode of these compounds in LN229 cells affects the intracellular polyamine metabolism and might underlie the more favorable cell proliferation inhibition in comparison with DFMO.

  6. Proliferating cells in suborbital tissue drive eye migration in flatfish.

    PubMed

    Bao, Baolong; Ke, Zhonghe; Xing, Jubin; Peatman, Eric; Liu, Zhanjiang; Xie, Caixia; Xu, Bing; Gai, Junwei; Gong, Xiaoling; Yang, Guimei; Jiang, Yan; Tang, Wenqiao; Ren, Daming

    2011-03-01

    The left/right asymmetry of adult flatfishes (Pleuronectiformes) is remarkable given the external body symmetry of the larval fish. The best-known change is the migration of their eyes: one eye migrates from one side to the other. Two extinct primitive pleuronectiformes with incomplete orbital migration have again attracted public attention to the mechanism of eye migration, a subject of speculation and research for over a century. Cranial asymmetry is currently believed to be responsible for eye migration. Contrary to that hypothesis, we show here that the initial migration of the eye is caused by cell proliferation in the suborbital tissue of the blind side and that the twist of frontal bone is dependent on eye migration. The inhibition of cell proliferation in the suborbital area of the blind side by microinjected colchicine was able to prevent eye migration and, thereafter, cranial asymmetry in juvenile Solea senegalensis (right sideness, Soleidae), Cynoglossus semilaevis (left sideness, Cynoglossidae), and Paralichthys olivaceus (left sideness, Paralichthyidae) with a bottom-dwelling lifestyle. Our results correct the current misunderstanding that eye migration is driven by the cranial asymmetry and simplify the explanation for broken left/right eye-symmetry. Our findings should help to focus the search on eye migration-related genes associated with cell proliferation. Finally, a novel model is proposed in this research which provides a reasonable explanation for differences in the migrating eye between, and sometimes within, different species of flatfish and which should aid in our overall understanding of eye migration in the ontogenesis and evolution of Pleuronectiformes.

  7. Stromelysin generates a fibronectin fragment that inhibits Schwann cell proliferation

    PubMed Central

    1992-01-01

    Our previous report (Muir, D., S. Varon, and M. Manthorpe. 1990. J. Cell Biol. 109:2663-2672) described the isolation and partial characterization of a 55-kD antiproliferative protein found in Schwann cell (SC) and schwannoma cell line-conditioned media and we concluded that SC proliferation is under negative autocrine control. In the present study the 55-kD protein was found to possess metalloprotease activity and stromelysin immunoreactivity. The SC-derived metalloprotease shares many properties with stromelysin isolated from other sources including the ability to cleave fibronectin (FN). Furthermore, limited proteolysis of FN by the SC-derived protease generated a FN fragment which itself expresses a potent antiproliferative activity for SCs. The active FN fragment corresponds to the 29-kD amino-terminal region of the FN molecule which was also identified as an active component in SC CM. Additional evidence that a proteolytic fragment of FN can possess antiproliferative activity for SCs was provided by the finding that plasmin can generate an amino- terminal FN fragment which mimicked the activity of the SC metalloprotease-generated antiproliferative FN fragment. Both the 55-kD SC metalloprotease and the 29-kD FN fragment could completely and reversibly inhibit proliferation of SCs treated with various mitogens and both were largely ineffective at inhibiting proliferation by immortalized or transformed SC lines. Normal and transformed SC types do secrete the proform of stromelysin, however, transformed cultures do not produce activated stromelysin and thus cannot generate the antiproliferative fragment of FN. These results suggest that, once activated, a SC-derived protease similar to stromelysin cleaves FN and generates an antiproliferative activity which can maintain normal SC quiescence in vitro. PMID:1730742

  8. Proliferating cells in psoriatic dermis are comprised primarily of T cells, endothelial cells, and factor XIIIa+ perivascular dendritic cells

    SciTech Connect

    Morganroth, G.S.; Chan, L.S.; Weinstein, G.D.; Voorhees, J.J.; Cooper, K.D. )

    1991-03-01

    Determination of the cell types proliferating in the dermis of patients with psoriasis should identify those cells experiencing activation or responding to growth factors in the psoriatic dermal milieu. Toward that end, sections of formalin-fixed biopsies obtained from 3H-deoxyuridine (3H-dU)-injected skin of eight psoriatic patients were immunostained, followed by autoradiography. Proliferating dermal cells exhibit silver grains from tritium emissions. The identity of the proliferating cells could then be determined by simultaneous visualization with antibodies specific for various cell types. UCHL1+ (CD45RO+) T cells (recall antigen-reactive helper T-cell subset) constituted 36.6 +/- 3.1% (mean +/- SEM, n = 6) of the proliferating dermal cells in involved skin, whereas Leu 18+ (CD45RA+) T cells (recall antigen naive T-cell subsets) comprised only 8.7 +/- 1.5% (n = 6). The Factor XIIIa+ dermal perivascular dendritic cell subset (24.9 +/- 1.5% of proliferating dermal cells, n = 6) and Factor VIII+ endothelial cells represented the two other major proliferating populations in lesional psoriatic dermis. Differentiated tissue macrophages, identified by phase microscopy as melanophages or by immunostaining with antibodies to Leu M1 (CD15) or myeloid histiocyte antigen, comprised less than 5% of the proliferating population in either skin type. In addition to calculating the relative proportions of these cells to each other as percent, we also determined the density of cells, in cells/mm2 of tissue. The density of proliferating cells within these populations was increased in involved versus uninvolved skin: UCHL1+, 9.0 +/- 1.7 cells/mm2 versus 1.8 +/- 0.6 cells/mm2, p less than 0.01; Factor XIIIa+, 6.0 +/- 0.7 cells/mm2 versus 1.5 +/- 0.5 cells/mm2, p less than 0.01; Factor VIII+, 5.5 +/- 1.4 cells/mm2 versus 0.0 cells/mm2, p less than 0.05.

  9. Matrix modulation of compensatory lung regrowth and progenitor cell proliferation in mice

    PubMed Central

    Shifren, A.; Mazan, M. R.; Gruntman, A. M.; Lascola, K. M.; Nolen-Walston, R. D.; Kim, C. F.; Tsai, L.; Pierce, R. A.; Mecham, R. P.; Ingenito, E. P.

    2010-01-01

    Mechanical stress is an important modulator of lung morphogenesis, postnatal lung development, and compensatory lung regrowth. The effect of mechanical stress on stem or progenitor cells is unclear. We examined whether proliferative responses of epithelial progenitor cells, including dually immunoreactive (CCSP and proSP-C) progenitor cells (CCSP+/SP-C+) and type II alveolar epithelial cells (ATII), are affected by physical factors found in the lung of emphysematics, including loss of elastic recoil, reduced elastin content, and alveolar destruction. Mice underwent single lung pneumonectomy (PNY) to modulate transpulmonary pressure (mechanical stress) and to stimulate lung regeneration. Control mice underwent sham thoracotomy. Plombage of different levels was employed to partially or completely abolish this mechanical stress. Responses to graded changes in transpulmonary pressure were assessed in elastin-insufficient mice (elastin +/−, ELN+/−) and elastase-treated mice with elastase-induced emphysema. Physiological regrowth, morphometry (linear mean intercept; Lmi), and the proliferative responses of CCSP+/SP-C+, Clara cells, and ATII were evaluated. Plombage following PNY significantly reduced transpulmonary pressure, regrowth, and CCSP+/SP-C+, Clara cell, and ATII proliferation following PNY. In the ELN+/− group, CCSP+/SP-C+ and ATII proliferation responses were completely abolished, although compensatory lung regrowth was not significantly altered. In contrast, in elastase-injured mice, compensatory lung regrowth was significantly reduced, and ATII but not CCSP+/SP-C+ proliferation responses were impaired. Elastase injury also reduced the baseline abundance of CCSP+/SP-C+, and CCSP+/SP-C+ were found to be displaced from the bronchioalveolar duct junction. These data suggest that qualities of the extracellular matrix including elastin content, mechanical stress, and alveolar integrity strongly influence the regenerative capacity of the lung, and the

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

    SciTech Connect

    Wu, William Ka Kei; Lee, Chung Wa; Cho, Chi Hin; Chan, Francis Ka Leung; Yu, Jun; Sung, Joseph Jao Yiu

    2011-06-10

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

  11. The role of intradermal proliferation of T-cells in the pathogenesis of psoriasis*

    PubMed Central

    Khairutdinov, Vladislav R.; Mikhailichenko, Anastasiya F.; Belousova, Irena E.; Kuligina, Ekatherina Sh.; Samtsov, Alexey V.; Imyanitov, Evgeny N.

    2017-01-01

    BACKGROUND Psoriasis is a common immune-mediated chronic inflammatory disease of the skin and joints, affecting 1-3% of the population. It is generally accepted that the pathogenesis of psoriasis involves accumulation of effector T-cells within lymph nodes and their subsequent migration into the skin through the blood system. Here we provide evidence that psoriatic plaque itself may serve as a source of inflammatory T-cells. OBJECTIVE We examined the intradermal proliferation of T-cells and the number of effector/memory (CD45RO+) T-cells in the skin of psoriatic patients at different periods of the disease. METHODS Skin samples were obtained from 41 patients with progressive psoriatic lesions; 18 of these patients also donated skin specimens during the remission of the disease. The control group consisted of 16 healthy subjects. Ki-67 immunohistochemical staining was applied to detect proliferating cells, CD3ε served as a T-cell marker, and CD45RA and CD45RO antibodies were utilized to discriminate between naive and effector/memory T-cells, respectively. RESULTS Progressive psoriatic lesions demonstrated Ki67 staining both in keratinocytes and in the CD3ε+ cells of dermal infiltrate. Median count of CD45RO+ cells per microscopic field was 15 in healthy controls, 59 in patients in remission and 208 in progressive psoriatic plaques. The observed differences demonstrated high level of statistical significance. STUDY LIMITATIONS Limited number of analyzed patients. CONCLUSION Progressive phase of psoriasis is characterized by intradermal proliferation of T-cells. Spots of regressed psoriatic lesions contain high number of CD45RO+ cells, which are likely to render an immunological memory. PMID:28225955

  12. Paracrine influence of human perivascular cells on the proliferation of adenocarcinoma alveolar epithelial cells

    PubMed Central

    Kim, Eunbi; Na, Sunghun; An, Borim; Yang, Se-Ran; Kim, Woo Jin; Ha, Kwon-Soo; Han, Eun-Taek; Park, Won Sun; Lee, Chang-Min; Lee, Ji Yoon

    2017-01-01

    Understanding the crosstalk mechanisms between perivascular cells (PVCs) and cancer cells might be beneficial in preventing cancer development and metastasis. In this study, we investigated the paracrine influence of PVCs derived from human umbilical cords on the proliferation of lung adenocarcinoma epithelial cells (A549) and erythroleukemia cells (TF-1α and K562) in vitro using Transwell® co-culture systems. PVCs promoted the proliferation of A549 cells without inducing morphological changes, but had no effect on the proliferation of TF-1α and K562 cells. To identify the factors secreted from PVCs, conditioned media harvested from PVC cultures were analyzed by antibody arrays. We identified a set of cytokines, including persephin (PSPN), a neurotrophic factor, and a key regulator of oral squamous cell carcinoma progression. Supplementation with PSPN significantly increased the proliferation of A549 cells. These results suggested that PVCs produced a differential effect on the proliferation of cancer cells in a cell-type dependent manner. Further, secretome analyses of PVCs and the elucidation of the molecular mechanisms could facilitate the discovery of therapeutic target(s) for lung cancer. PMID:28280409

  13. Smoc2 potentiates proliferation of hepatocellular carcinoma cells via promotion of cell cycle progression

    PubMed Central

    Su, Jing-Ran; Kuai, Jing-Hua; Li, Yan-Qing

    2016-01-01

    AIM To determine the influence of Smoc2 on hepatocellular carcinoma (HCC) cell proliferation and to find a possible new therapeutic target for preventing HCC progression. METHODS We detected expression of Smoc2 in HCC tissues and corresponding non-tumor liver (CNL) tissues using PCR, western blot, and immunohistochemistry methods. Subsequently, we down-regulated and up-regulated Smoc2 expression using siRNA and lentivirus transfection assay, respectively. Then, we identified the effect of Smoc2 on cell proliferation and cell cycle using CCK-8 and flow cytometry, respectively. The common cell growth signaling influenced by Smoc2 was detected by western blot assay. RESULTS The expression of Smoc2 was significantly higher in HCC tissues compared with CNL tissues. Overexpression of Smoc2 promoted HCC cell proliferation and cell cycle progression. Down-regulation of Smoc2 led to inhibition of cell proliferation and cell cycle progression. Smoc2 had positive effect on ERK and AKT signaling. CONCLUSION Smoc2 promotes the proliferation of HCC cells through accelerating cell cycle progression and might act as an anti-cancer therapeutic target in the future. PMID:28018113

  14. Potassium channel blockers quinidine and caesium halt cell proliferation in C6 glioma cells via a polyamine-dependent mechanism.

    PubMed

    Weiger, T M; Colombatto, S; Kainz, V; Heidegger, W; Grillo, M A; Hermann, A

    2007-04-01

    Potassium channels are ubiquitous in cells and serve essential functions in physiology and pathophysiology. Potassium channel blockers have been shown to block tumour growth by arresting cells at the G(0)/G(1) checkpoint of the cell cycle. We investigated the effect of quinidine and caesium (Cs(+)) on cell proliferation, LDH (lactate dehydrogenase) release, free internal calcium, membrane potential, polyamine concentration, ODC (ornithine decarboxylase) activity and polyamine uptake in C6 glioma cells. The EC(50) for reducing cell proliferation was 112 microM for quinidine, whereas Cs(+) was less effective with an EC(50) of 4.75 mM. KCl or sucrose did not affect proliferation. LDH release was augmented by quinidine. Quinidine caused a transient increase in free internal calcium but decreased calcium after a 48 h incubation period. Further 300 microM quinidine depolarized the cell membrane in a similar range as did 30 mM KCl. Quinidine decreased cellular putrescine beyond detection levels while spermidine and spermine remained unaffected. ODC activity was reduced. Addition of putrescine could not override the antiproliferative effect owing to a reduced activity of the polyamine transporter. Our study indicates that the antiproliferative effect of quinidine is not due to a simple membrane depolarization but is caused by a block of ODC activity.

  15. CXCL7 promotes proliferation and invasion of cholangiocarcinoma cells.

    PubMed

    Guo, Qian; Jian, Zhixiang; Jia, Baoqing; Chang, Liang

    2017-02-01

    CXCL7 is an important chemoattractant cytokine, which signals through binding to its receptor CXCR2. Recent studies have demonstrated that the CXCL7/CXCR2 signaling plays a promoting role in several common malignancies, including lung, renal, colon, and breast cancer. However, the regulatory role of CXCL7, in cholangiocarcinoma, as well as the underlying mechanism, has not been previously reported. Herein, we found more positive expression of CXCL7 in cholangiocarcinoma tissues compared to adjacent non-tumor tissues. High CXCL7 expression was significantly correlated with poor differentiation, lymph node metastasis, vascular invasion and advanced clinical stage, but was not associated with age, gender, or tumor size. Besides, the expression of CXCL7 was significantly associated with the Ki67 expression, but not associated with CA199, AFP, or P53 expression in cholangiocarcinoma. Moreover, the overall survival of cholangiocarcinoma patients with high CXCL7 expression was significantly shorter than those with low CXCL7 expression. In vitro study indicated that CXCL7 and CXCR2 were also positively expressed in several common cholangiocarcinoma cell lines, including HuCCT1, HuH28, QBC939, EGI-1, OZ and WITT. SiRNA-induced inhibition of CXCL7 significantly reduced the proliferation and invasion of QBC939 cells. On the contrary, overexpression of CXCL7 markedly promoted these malignant phenotypes of QBC939 cells. Of note, the conditioned medium of CXCL7-overexpresing human hepatic stellate cells could also promote the proliferation and invasion of QBC939 cells, suggesting that CXCL7 may also play an oncogenic role in cholangiocarcinoma in a paracrine-dependent manner, not only in an autocrine-dependent manner. Molecular assay data suggested that the AKT signaling pathway was involved in the CXCL7-mediated malignant phenotypes of QBC939 cells. In summary, our study suggests that CXCL7 plays a promoting role in regulating the growth and metastasis of cholangiocarcinoma.

  16. PPARδ regulates satellite cell proliferation and skeletal muscle regeneration

    PubMed Central

    2011-01-01

    Peroxisome proliferator-activated receptors (PPARs) are a class of nuclear receptors that play important roles in development and energy metabolism. Whereas PPARδ has been shown to regulate mitochondrial biosynthesis and slow-muscle fiber types, its function in skeletal muscle progenitors (satellite cells) is unknown. Since constitutive mutation of Pparδ leads to embryonic lethality, we sought to address this question by conditional knockout (cKO) of Pparδ using Myf5-Cre/Pparδflox/flox alleles to ablate PPARδ in myogenic progenitor cells. Although Pparδ-cKO mice were born normally and initially displayed no difference in body weight, muscle size or muscle composition, they later developed metabolic syndrome, which manifested as increased body weight and reduced response to glucose challenge at age nine months. Pparδ-cKO mice had 40% fewer satellite cells than their wild-type littermates, and these satellite cells exhibited reduced growth kinetics and proliferation in vitro. Furthermore, regeneration of Pparδ-cKO muscles was impaired after cardiotoxin-induced injury. Gene expression analysis showed reduced expression of the Forkhead box class O transcription factor 1 (FoxO1) gene in Pparδ-cKO muscles under both quiescent and regenerating conditions, suggesting that PPARδ acts through FoxO1 in regulating muscle progenitor cells. These results support a function of PPARδ in regulating skeletal muscle metabolism and insulin sensitivity, and they establish a novel role of PPARδ in muscle progenitor cells and postnatal muscle regeneration. PMID:22040534

  17. Ethanol suppresses T cell proliferation without inhibiting interleukin 2 (IL2) production and IL2 receptor (IL2R) expression

    SciTech Connect

    Chang, M.P.; Norman, D.C. Univ. of California, Los Angeles )

    1991-03-11

    The effect of extended ethanol consumption of young C57BL/6J mice on T cell proliferation was studied. Splenic cells of young mice, fed with one of three different liquid diets for 6-7 weeks were cultured with Con A to assess T cell proliferation and production of IL2. Then, the proliferative response of splenic cells to PMA/ionomycin was assessed. Finally, Con A-activated T blast cells were assessed for their ability to express IL2R and to respond to IL2. The results showed that both Con A-induced mitogenesis and IL2-dependent proliferation of T cells from ethanol diet-fed mice were diminished as compared to that of maltose-substitute diet or standard liquid diet. However, the ability of T cells from ethanol diet-fed mice to produce IL2 and to express IL2R was not affected. Furthermore, the magnitude of ethanol-mediated suppression of T cell proliferation induced by PMA/ionomycin was comparable to that induced by Con A. These results taken together suggest that ethanol suppresses T cell proliferation by interfering with events following the IL2-IL2R interaction.

  18. Linkage of E2F1 transcriptional network and cell proliferation with respiratory chain activity in breast cancer cells.

    PubMed

    Mori, Kazunori; Uchida, Tetsu; Fukumura, Motonori; Tamiya, Shigetoshi; Higurashi, Masato; Sakai, Hirosato; Ishikawa, Fumihiro; Shibanuma, Motoko

    2016-07-01

    Mitochondria are multifunctional organelles; they have been implicated in various aspects of tumorigenesis. In this study, we investigated a novel role of the basal electron transport chain (ETC) activity in cell proliferation by inhibiting mitochondrial replication and transcription (mtR/T) using pharmacological and genetic interventions, which depleted mitochondrial DNA/RNA, thereby inducing ETC deficiency. Interestingly, mtR/T inhibition did not decrease ATP levels despite deficiency in ETC activity in different cell types, including MDA-MB-231 breast cancer cells, but it severely impeded cell cycle progression, specifically progression during G2 and/or M phases in the cancer cells. Under these conditions, the expression of a group of cell cycle regulators was downregulated without affecting the growth signaling pathway. Further analysis suggested that the transcriptional network organized by E2F1 was significantly affected because of the downregulation of E2F1 in response to ETC deficiency, which eventually resulted in the suppression of cell proliferation. Thus, in this study, the E2F1-mediated ETC-dependent mechanism has emerged as the regulatory mechanism of cell cycle progression. In addition to E2F1, FOXM1 and BMYB were also downregulated, which contributed specifically to the defects in G2 and/or M phase progression. Thus, ETC-deficient cancer cells lost their growing ability, including their tumorigenic potential in vivo. ETC deficiency abolished the production of reactive oxygen species (ROS) from the mitochondria and a mitochondria-targeted antioxidant mimicked the deficiency, thereby suggesting that ETC activity signaled through ROS production. In conclusion, this novel coupling between ETC activity and cell cycle progression may be an important mechanism for coordinating cell proliferation and metabolism.

  19. hCLP46 regulates U937 cell proliferation via Notch signaling pathway

    SciTech Connect

    Ma, Wenzhan; Du, Jie; Chu, Qiaoyun; Wang, Youxin; Liu, Lixin; Song, Manshu; Wang, Wei

    2011-04-29

    Highlights: {yields} Knock down of hCLP46 by RNAi impairs mammalian Notch signaling. {yields} hCLP46 affects neither cell surface Notch1 expression nor ligand-receptor binding. {yields} Knock down of hCLP46 inhibits U937 cell-growth by up-regulation of CDKN1B. -- Abstract: Human CAP10-like protein 46 kDa (hCLP46) is the homolog of Rumi, which is the first identified protein O-glucosyltransferase that modifies Notch receptor in Drosophila. Dysregulation of hCLP46 occurs in many hematologic diseases, but the role of hCLP46 remains unclear. Knockdown of hCLP46 by RNA interference resulted in decreased protein levels of endogenous Notch1, Notch intracellular domain (NICD) and Notch target gene Hes-1, suggesting the impairment of the Notch signaling. However, neither cell surface Notch expression nor ligand binding activities were affected. In addition, down-regulated expression of hCLP46 inhibited the proliferation of U937 cells, which was correlated with increased cyclin-dependent kinase inhibitor (CDKI) CDKN1B (p27) and decreased phosphorylation of retinoblastoma (RB) protein. We showed that lack of hCLP46 results in impaired ligand induced Notch activation in mammalian cell, and hCLP46 regulates the proliferation of U937 cell through CDKI-RB signaling pathway, which may be important for the pathogenesis of leukemia.

  20. Ultrasound fails to induce proliferation of human brain and mouse endothelial cell lines

    NASA Astrophysics Data System (ADS)

    Rodemer, Claus; Jenne, Jürgen; Fatar, Marc; Hennerici, Michael G.; Meairs, Stephen

    2012-11-01

    Both in vitro and in vivo studies suggest that ultrasound (US) is capable of inducing angiogenesis. There is no information, however, on whether ultrasound can induce proliferation of brain endothelial cells. We therefore explored the angiogenic potential of ultrasound on a novel immortalised human brain endothelial cell line (hCMEC/D3) and on mouse brain microvascular endothelial cells (bEND3). Ultrasound failed to enhance cell proliferation in both cell lines at all acoustic pressures studied. Endothelial cell damage occurred at 0.24 MPa with significantly slower proliferation. Cells growing in Opticell{trade mark, serif} dishes did not show damage or reduced proliferation at these pressures.

  1. In vitro pituitary and thyroid cell proliferation assays and their relevance as alternatives to animal testing.

    PubMed

    Jomaa, Barae; Aarts, Jac M M J G; de Haan, Laura H J; Peijnenburg, Ad A C M; Bovee, Toine F H; Murk, Albertinka J; Rietjens, Ivonne M C M

    2013-01-01

    This study investigates the in vitro effect of eleven thyroid-active compounds known to affect pituitary and/or thyroid weights in vivo, using the proliferation of GH3 rat pituitary cells in the so-called "T-screen," and of FRTL-5 rat thyroid cells in a newly developed test denoted "TSH-screen" to gain insight into the relative value of these in vitro proliferation tests for an integrated testing strategy (ITS) for thyroid activity. Pituitary cell proliferation in the T-screen was stimulated by three out of eleven tested compounds, namely thyrotropin releasing hormone (TRH), triiodothyronine (T3) and thyroxine (T4). Of these three compounds, only T4 causes an increase in relative pituitary weight, and thus T4 was the only compound for which the effect in the in vitro assay correlated with a reported in vivo effect. As to the newly developed TSH-screen, two compounds had an effect, namely, thyroid-stimulating hormone (TSH) induced and T4 antagonized FRTL-5 cell proliferation. These effects correlated with in vivo changes induced by these compounds on thyroid weight. Altogether, the results indicate that most of the selected compounds affect pituitary and thyroid weights by modes of action different from a direct thyroid hormone receptor (THR) or TSH receptor (TSHR)-mediated effect, and point to the need for additional in vitro tests for an ITS. Additional analysis of the T-screen revealed a positive correlation between the THR-mediated effects of the tested compounds in vitro and their effects on relative heart weight in vivo, suggesting that the T-screen may directly predict this THR-mediated in vivo adverse effect.

  2. The inhibitory effects of mycobacterial lipoarabinomannan and polysaccharides upon polyclonal and monoclonal human T cell proliferation.

    PubMed Central

    Moreno, C; Mehlert, A; Lamb, J

    1988-01-01

    Lipoarabinomannan from Mycobacterium tuberculosis was able to inhibit antigen induced T cell proliferation of human CD4+ T cell clones specific for influenza virus. The inhibitory effect was also present when peripheral human T cells were stimulated with crude mycobacterial antigen extracts. Non-specific T cell stimulation, i.e. IL-2, PHA and anti-CD3 antibodies coupled to beads, was not affected. The inhibitory property was also found when arabinomannan and arabinogalactan of mycobacterial origin were tested but not with other unrelated polysaccharides used as controls. The effect appears to be related to the processing of the antigen by the antigen-presenting cells, since it was evident when T cell clones were stimulated with whole virus, whereas stimulation with a synthetic peptide containing the relevant epitope was not inhibitable. PMID:3147152

  3. Cesium reversibly suppresses HeLa cell proliferation by inhibiting cellular metabolism.

    PubMed

    Kobayashi, Daisuke; Kakinouchi, Kei; Nagae, Tomoki; Nagai, Toshihiko; Shimura, Kiyohito; Hazama, Akihiro

    2017-03-01

    The aim of the present study was to investigate the influence of Cs(+) on cultured human cells. We find that HeLa cell growth is suppressed by the addition of 10 mm CsCl into the culture media. In the Cs(+) -treated cells, the intracellular Cs(+) and K(+) concentrations are increased and decreased, respectively. This leads to a decrease in activity of the glycolytic enzyme pyruvate kinase, which uses K(+) as a cofactor. Cs(+) -treated cells show an intracellular pH shift towards alkalization. Based on these results, CsCl presumably suppresses HeLa cell proliferation by inducing an intracellular cation imbalance that affects cell metabolism. Our findings may have implications for the use of Cs(+) in cancer therapy.

  4. An assay for macrophage-mediated regulation of endothelial cell proliferation.

    PubMed

    Khan, Aslam Ali; Apte, Rajendra S

    2008-01-01

    We have developed an assay that quantifies the potential of macrophages to regulate proliferation of endothelial cells. We show that young mice macrophages can be distinguished from old mice macrophages by their ability to inhibit vascular endothelial cell proliferation. While young mice macrophages robustly inhibit proliferation, old mice macrophages fail to do so and actually promote the proliferation of endothelial cells. In this report, we outline a technique that directly assesses the effect of macrophages on modulation of endothelial cell proliferation. This assay will help us in understanding the mechanisms of macrophage function in several disease states characterized by abnormal angiogenesis including cancers, angiogenic eye disease and atherosclerotic heart disease.

  5. Proliferation and differentiation of neural stem cells irradiated with X-rays in logarithmic growth phase.

    PubMed

    Isono, Mayu; Otsu, Masahiro; Konishi, Teruaki; Matsubara, Kana; Tanabe, Toshiaki; Nakayama, Takashi; Inoue, Nobuo

    2012-07-01

    Exposure of the fetal brain to ionizing radiation causes congenital brain abnormalities. Normal brain formation requires regionally and temporally appropriate proliferation and differentiation of neural stem cells (NSCs) into neurons and glia. Here, we investigated the effects of X-irradiation on proliferating homogenous NSCs prepared from mouse ES cells. Cells irradiated with X-rays at a dose of 1Gy maintained the capabilities for proliferation and differentiation but stopped proliferation temporarily. In contrast, the cells ceased proliferation following irradiation at a dose of >5Gy. These results suggest that irradiation of the fetal brain at relatively low doses may cause congenital brain abnormalities as with relatively high doses.

  6. Supporting Aspartate Biosynthesis Is an Essential Function of Respiration in Proliferating Cells.

    PubMed

    Sullivan, Lucas B; Gui, Dan Y; Hosios, Aaron M; Bush, Lauren N; Freinkman, Elizaveta; Vander Heiden, Matthew G

    2015-07-30

    Mitochondrial respiration is important for cell proliferation; however, the specific metabolic requirements fulfilled by respiration to support proliferation have not been defined. Here, we show that a major role of respiration in proliferating cells is to provide electron acceptors for aspartate synthesis. This finding is consistent with the observation that cells lacking a functional respiratory chain are auxotrophic for pyruvate, which serves as an exogenous electron acceptor. Further, the pyruvate requirement can be fulfilled with an alternative electron acceptor, alpha-ketobutyrate, which provides cells neither carbon nor ATP. Alpha-ketobutyrate restores proliferation when respiration is inhibited, suggesting that an alternative electron acceptor can substitute for respiration to support proliferation. We find that electron acceptors are limiting for producing aspartate, and supplying aspartate enables proliferation of respiration deficient cells in the absence of exogenous electron acceptors. Together, these data argue a major function of respiration in proliferating cells is to support aspartate synthesis.

  7. 2,3,7,8-Tetrachlorodibenzo-p-dioxin stimulates proliferation of HAPI microglia by affecting the Akt/GSK-3β/cyclin D1 signaling pathway.

    PubMed

    Xu, Guangfei; Li, Yuanye; Yoshimoto, Katsuhiko; Wu, Qiyun; Chen, Gang; Iwata, Takeo; Mizusawa, Noriko; Wan, Chunhua; Nie, Xiaoke

    2014-01-30

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental toxin that induces apoptosis of neurons and a pro-inflammatory response in microglial cells. First, we found that TCDD induced proliferation of HAPI microglial cells in a dose- and time-dependent manner. Flow cytometry analysis showed that this proliferation by TCDD was due to mainly enhancing the G1 to S phase transition. Next, it was found that TCDD treatment led to up-regulation of cyclin D1, which induces cell cycle progression from G1 to S phase, in a time-dependent manner. As for molecular mechanism, we revealed that TCDD was capable of inducing Akt phosphorylation and activation, resulting in phosphorylation and inactivation of glycogen synthase kinase-3β (GSK-3β). Inactivated GSK-3β attenuated proteasomal degradation of cyclin D1 by reducing Thr(286)-phosphorylated cyclin D1 levels. Moreover, inactivated GSK-3β increased cyclin D1 gene transcription by increasing its transcription factor β-catenin in the nucleus. Further, blockage of phosphoinositide 3-kinase/Akt kinase with their specific inhibitors, LY294002 and Akt 1/2 kinase inhibitor, significantly reduced TCDD-enhanced proliferation of HAPI microglial cells. In conclusion, TCDD stimulates proliferation of HAPI microglial cells by affecting the Akt/GSK-3β/cyclin D1 signaling pathway.

  8. Temperature effect on proliferation and differentiation of satellite cells from turkeys with different growth rates.

    PubMed

    Clark, D L; Coy, C S; Strasburg, G M; Reed, K M; Velleman, S G

    2016-04-01

    Poultry selected for growth have an inefficient thermoregulatory system and are more sensitive to temperature extremes. Satellite cells are precursors to skeletal muscle and mediate all posthatch muscle growth. Their physiological functions are affected by temperature. The objective of the current study was to determine how temperature affects satellite cells isolated from the pectoralis major (p. major) muscle (breast muscle) of turkeys selected for increased 16 wk body weight (F line) in comparison to a randombred control line (RBC2) from which the F line originated. Pectoralis major muscle satellite cells were thermally challenged by culturing between 33°C and 43°C to analyze the effects of cold and heat on proliferation and differentiation as compared to control temperature of 38°C. Expression levels of myogenic regulatory factors: myogenic differentiation factor 1 (MYOD1) and myogenin (MYOG) were quantified by quantitative polymerase chain reaction (qPCR). At all sampling times, proliferation increased at a linear rate across temperature in both the RBC2 and F lines. Differentiation also increased at a linear rate across temperature from 33 to 41°C at all sampling times in both the F and RBC2 lines. Satellite cells isolated from F line turkeys were more sensitive to both hot and cold temperatures as proliferation and differentiation increased to a greater extent across temperature (33 to 43°C) when compared with the RBC2 line. Expression of MYOD1 and MYOG increased as temperatures increased from 33 to 41°C at all sampling times in both the F and RBC2 lines. These results demonstrate that satellite cell function is sensitive to both cold and hot temperatures and p. major muscle satellite cells from F line turkeys are more sensitive to temperature extremes than RBC2 satellite cells.

  9. RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells

    SciTech Connect

    Wang, Houcai; Yu, Jing; Zhang, Lixia; Xiong, Yuanyuan; Chen, Shuying; Xing, Haiyan; Tian, Zheng; Tang, Kejing; Wei, Hui; Rao, Qing; Wang, Min; Wang, Jianxiang

    2014-04-18

    Highlights: • RPS27a expression was up-regulated in advanced-phase CML and AL patients. • RPS27a knockdown changed biological property of K562 and K562/G01 cells. • RPS27a knockdown affected Raf/MEK/ERK, P21 and BCL-2 signaling pathways. • RPS27a knockdown may be applicable for new combination therapy in CML patients. - Abstract: Ribosomal protein S27a (RPS27a) could perform extra-ribosomal functions besides imparting a role in ribosome biogenesis and post-translational modifications of proteins. The high expression level of RPS27a was reported in solid tumors, and we found that the expression level of RPS27a was up-regulated in advanced-phase chronic myeloid leukemia (CML) and acute leukemia (AL) patients. In this study, we explored the function of RPS27a in leukemia cells by using CML cell line K562 cells and its imatinib resistant cell line K562/G01 cells. It was observed that the expression level of RPS27a was high in K562 cells and even higher in K562/G01 cells. Further analysis revealed that RPS27a knockdown by shRNA in both K562 and K562G01 cells inhibited the cell viability, induced cell cycle arrest at S and G2/M phases and increased cell apoptosis induced by imatinib. Combination of shRNA with imatinib treatment could lead to more cleaved PARP and cleaved caspase-3 expression in RPS27a knockdown cells. Further, it was found that phospho-ERK(p-ERK) and BCL-2 were down-regulated and P21 up-regulated in RPS27a knockdown cells. In conclusion, RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells. It appears that drugs targeting RPS27a combining with tyrosine kinase inhibitor (TKI) might represent a novel therapy strategy in TKI resistant CML patients.

  10. Calpain-3 Impairs Cell Proliferation and Stimulates Oxidative Stress-Mediated Cell Death in Melanoma Cells

    PubMed Central

    Moretti, Daniele; Del Bello, Barbara; Allavena, Giulia; Corti, Alessandro; Signorini, Cinzia; Maellaro, Emilia

    2015-01-01

    Calpain-3 is an intracellular cysteine protease, belonging to Calpain superfamily and predominantly expressed in skeletal muscle. In human melanoma cell lines and biopsies, we previously identified two novel splicing variants (hMp78 and hMp84) of Calpain-3 gene (CAPN3), which have a significant lower expression in vertical growth phase melanomas and, even lower, in metastases, compared to benign nevi. In the present study, in order to investigate the pathophysiological role played by the longer Calpain-3 variant, hMp84, in melanoma cells, we over-expressed it in A375 and HT-144 cells. In A375 cells, the enforced expression of hMp84 induces p53 stabilization, and modulates the expression of a few p53- and oxidative stress-related genes. Consistently, hMp84 increases the intracellular production of ROS (Reactive Oxygen Species), which lead to oxidative modification of phospholipids (formation of F2-isoprostanes) and DNA damage. Such events culminate in an adverse cell fate, as indicated by the decrease of cell proliferation and by cell death. To a different extent, either the antioxidant N-acetyl-cysteine or the p53 inhibitor, Pifithrin-α, recover cell viability and decrease ROS formation. Similarly to A375 cells, hMp84 over-expression causes inhibition of cell proliferation, cell death, and increase of both ROS levels and F2-isoprostanes also in HT-144 cells. However, in these cells no p53 accumulation occurs. In both cell lines, no significant change of cell proliferation and cell damage is observed in cells over-expressing the mutant hMp84C42S devoid of its enzymatic activity, suggesting that the catalytic activity of hMp84 is required for its detrimental effects. Since a more aggressive phenotype is expected to benefit from down-regulation of mechanisms impairing cell growth and survival, we envisage that Calpain-3 down-regulation can be regarded as a novel mechanism contributing to melanoma progression. PMID:25658320

  11. The knockdown of TASK-1 channels improved the proliferation of N2A cells.

    PubMed

    Hao, Xuran; Li, Xiantao

    2015-02-01

    Previous studies indicated that K(+) channels, such as voltage-gated Kv channels, were involved in the apoptosis and proliferation of neurons. In the experiments here, the small interfering RNAs (siRNAs) targeted against TASK-1, an acid-sensitive member of two-pore domain K(+) (K2P) channel family, were transfected into mouse neuroblastoma N2A cells. This treatment induced a reduction of messenger RNA (mRNA) level of TASK-1 by 61%. As a negative control, however, the transfection of scrambled siRNAs (scRNA) did not significantly affect the expression of TASK-1 in N2A cells. Furthermore, exposure to TASK-1-specific siRNAs (siTASK-1) for 48 h also substantially increased the proliferation rates of N2A cells by 25.8%, but no effect was observed in scRNA-treated cells. These data implied that TASK-1 channels may participate in the regulation of neuronal proliferation.

  12. Emodin and Aloe-Emodin Suppress Breast Cancer Cell Proliferation through ER α Inhibition.

    PubMed

    Huang, Pao-Hsuan; Huang, Chih-Yang; Chen, Mei-Chih; Lee, Yueh-Tsung; Yue, Chia-Herng; Wang, Hsin-Yi; Lin, Ho

    2013-01-01

    The anthraquinones emodin and aloe-emodin are abundant in rhubarb. Several lines of evidence indicate that emodin and aloe-emodin have estrogenic activity as phytoestrogens. However, their effects on estrogen receptor α (ER α ) activation and breast cancer cell growth remain controversial. The goal of this study is to investigate the effects and molecular mechanisms of emodin and aloe-emodin on breast cancer cell proliferation. Our results indicate that both emodin and aloe-emodin are capable of inhibiting breast cancer cell proliferation by downregulating ER α protein levels, thereby suppressing ER α transcriptional activation. Furthermore, aloe-emodin treatment led to the dissociation of heat shock protein 90 (HSP90) and ER α and increased ER α ubiquitination. Although emodin had similar effects to aloe-emodin, it was not capable of promoting HSP90/ER α dissociation and ER α ubiquitination. Protein fractionation results suggest that aloe-emodin tended to induce cytosolic ER α degradation. Although emodin might induce cytosolic ER α degradation, it primarily affected nuclear ER α distribution similar to the action of estrogen when protein degradation was blocked. In conclusion, our data demonstrate that emodin and aloe-emodin specifically suppress breast cancer cell proliferation by targeting ER α protein stability through distinct mechanisms. These findings suggest a possible application of anthraquinones in preventing or treating breast cancer in the future.

  13. Effect of elevated selenium intakes on mammary cell proliferation in rats

    SciTech Connect

    Salbe, A.D.; Albanes, D.; Winick, M.; Taylor, P.R.; Levander, O.A. National Institutes of Health, Bethesda, MD )

    1991-03-15

    Elevated selenium (Se) intakes and calorie restriction (CR) inhibit mammary tumorigenesis in experimental animals. The present study was designed to investigate cell proliferation in the mammary tissue gland. Female weanling Sprague-Dawley rats were divided into 4 groups: control, 40% CR, 4 or 6 ppm Se in water as selenate. Control rats and Se rats were fed a control diet ad lib. CR rats were pair-fed 40% less than controls with a diet providing equal nutrients except carbohydrate calories. After 3 weeks, rats were injected with ({sup 3}H)-thymidine and killed 1 hr later. Se at 4 ppm significantly decreased only the number of ducts, whereas 6 ppm Se decreased both the number of ducts as well as the number and percent of labeled cells. CR had no effect on mammary cell proliferation. These results suggest that elevated Se intakes may protect against mammary tumorigenesis by decreasing cell proliferation, a mechanism which may affect the dose-response of the genotoxic chemicals frequently used as initiating agents in animal experiments.

  14. Emodin and Aloe-Emodin Suppress Breast Cancer Cell Proliferation through ERα Inhibition

    PubMed Central

    Huang, Pao-Hsuan; Huang, Chih-Yang; Chen, Mei-Chih; Lee, Yueh-Tsung; Yue, Chia-Herng; Wang, Hsin-Yi

    2013-01-01

    The anthraquinones emodin and aloe-emodin are abundant in rhubarb. Several lines of evidence indicate that emodin and aloe-emodin have estrogenic activity as phytoestrogens. However, their effects on estrogen receptor α (ERα) activation and breast cancer cell growth remain controversial. The goal of this study is to investigate the effects and molecular mechanisms of emodin and aloe-emodin on breast cancer cell proliferation. Our results indicate that both emodin and aloe-emodin are capable of inhibiting breast cancer cell proliferation by downregulating ERα protein levels, thereby suppressing ERα transcriptional activation. Furthermore, aloe-emodin treatment led to the dissociation of heat shock protein 90 (HSP90) and ERα and increased ERα ubiquitination. Although emodin had similar effects to aloe-emodin, it was not capable of promoting HSP90/ERα dissociation and ERα ubiquitination. Protein fractionation results suggest that aloe-emodin tended to induce cytosolic ERα degradation. Although emodin might induce cytosolic ERα degradation, it primarily affected nuclear ERα distribution similar to the action of estrogen when protein degradation was blocked. In conclusion, our data demonstrate that emodin and aloe-emodin specifically suppress breast cancer cell proliferation by targeting ERα protein stability through distinct mechanisms. These findings suggest a possible application of anthraquinones in preventing or treating breast cancer in the future. PMID:23864887

  15. Cell adhesion and proliferation on polyethylene grafted with Au nanoparticles

    NASA Astrophysics Data System (ADS)

    Kasálková, N. Slepičková; Slepička, P.; Kolská, Z.; Sajdl, P.; Bačáková, L.; Rimpelová, S.; Švorčík, V.

    2012-02-01

    Plasma treatment and subsequent Au nano-particles grafting of polyethylene (PE) lead to changes in surface morphology, roughness and wettability, significantly increasing the attractiveness of the material for cells. The PE samples were exposed to argon plasma. Plasma modified PE was chemically grafted by immersion to biphenyldithiol and consequently into solution of Au nano-particles. Changes in chemical structure of the modified PE were studied using X-ray Photoelectron Spectroscopy (XPS) and electrokinetic analysis ( ζ-potential). The surface wettability of the modified PE samples was examined by measurement of the contact angle by standard goniometry. The surface morphology of the plasma modified PE and that grafted with Au nano-particles was studied by Atomic Force Microscopy (AFM). The modified PE samples were seeded with rat vascular smooth muscle cells (VSMCs) and their adhesion and proliferation were studied. Chemically bounded biphenyldithiol increases the number of the incorporated gold nano-particles and changes sample surface properties. The presence of the biphenyldithiol and the gold nano-particles on the PE surface influences dramatically adhesion and proliferation of VSMCs.

  16. IL-15 inhibits pre-B cell proliferation by selectively expanding Mac-1{sup +}B220{sup +} NK cells

    SciTech Connect

    Nakajima, Shinsuke; Hida, Shigeaki; Taki, Shinsuke

    2008-05-16

    Natural killer (NK) cells are the cells critical for inhibition of repopulation of allogenic bone marrow cells. However, it is not well known if NK cells affect autologous lymphopoiesis. Here, we observed that NK cells could inhibit pre-B cell proliferation in vitro driven by interleukin (IL)-7 in a manner dependent on IL-15. Interestingly, the great majority of expanding NK cells were Mac-1{sup +}B220{sup +}, a recently identified potent interferon (IFN)-{gamma} producer. Indeed, IFN-{gamma} was produced in those cultures, and pre-B cells lacking IFN-{gamma} receptors, but not those lacking type I IFN receptors, were resistant to such an inhibition. Furthermore, even NK cells from mice lacking {beta}2-microglobulin, which were known to be functionally dampened, inhibited pre-B cell proliferation as well. Thus, activated NK cells, which were expanded selectively by IL-15, could potentially regulate B lymphopoiesis through IFN-{gamma} beyond the selection imposed upon self-recognition.

  17. Evidence for cell proliferation in the sheep brain and its down-regulation by parturition and interactions with the young.

    PubMed

    Brus, M; Meurisse, M; Franceschini, I; Keller, M; Lévy, F

    2010-11-01

    Production of new neurons continues throughout life in the subventricular zone (SVZ) and the dentate gyrus (DG) of the hippocampus and is influenced by both endocrine and social factors. In sheep parturition is associated with the establishment of a selective bond with the young based on an olfactory learning. The possibility exists that endocrine changes at parturition together with interactions with the young modulate cell proliferation in the neurogenic zones. In the present study, we first investigated the existence of cell proliferation in sheep. Newly born cells labeled by the cell proliferation marker 5-bromo-2'-deoxyuridine (BrdU) were found in the SVZ, the main olfactory bulb (MOB) and the DG and completely co-localized with Ki-67, another mitotic marker. Forty to 50% of the BrdU-labeled cells contained GFAP suggestive of the presence of neural stem cells. Secondly, parturition with or without interactions with the lamb for 2 days, down-regulated the number of BrdU-labeled cells in the 3 proliferation sites in comparison to no pregnancy. An additional control provided evidence that this effect is specific to early postpartum period: estrus with interactions with males did not affect cell proliferation. Our results provide the first characterization of neural cell proliferation in the SVZ, the DG and unexpectedly in the MOB of adult sheep. We hypothesize that the down-regulation of cell proliferation observed in the early postpartum period could facilitate the olfactory perceptual and memory demands associated with maternal behavior by favouring the survival and integration of neurons born earlier.

  18. Research Note Mesenchymal stem cells from skin lesions of psoriasis patients promote proliferation and inhibit apoptosis of HaCaT cells.

    PubMed

    Liu, R F; Wang, F; Wang, Q; Zhao, X C; Zhang, K M

    2015-12-22

    Psoriasis is an inflammatory skin disease characterized by excessive proliferation and abnormal differentiation and apoptosis of keratinocytes (KCs). Mesenchymal stem cells (MSCs) from skin lesions of psoriasis patients demonstrate abnormal cytokine secretion, which may affect KC proliferation and apoptosis. Here, we explored how MSCs from skin lesions of psoriasis patients affect HaCaT cell proliferation and apoptosis. First, flow cytometry and multipotent differentiation methods were used to identify skin MSCs, which were then co-cultured with HaCaT cells. HaCaT cell proliferation was analyzed in real-time, and cell cycle progression and apoptosis were assessed by flow cytometry. Cell morphologies and multipotencies of skin MSCs were similar between the psoriasis group and healthy control group, with high levels of CD29, CD44, CD73, CD90, and CD105 and limited expression of CD34, CD45, and HLA-DR. MSCs from skin lesions of psoriasis patients promote KC proliferation more potently and are less capable of inducing KC apoptosis. This may underlie KC proliferation and abnormal apoptosis in psoriasis skin lesions, which results in abnormal thickening of the epidermis.

  19. Myricetin inhibits proliferation and induces apoptosis and cell cycle arrest in gastric cancer cells.

    PubMed

    Feng, Jianfang; Chen, Xiaonan; Wang, Yuanyuan; Du, Yuwen; Sun, Qianqian; Zang, Wenqiao; Zhao, Guoqiang

    2015-10-01

    Myricetin is a flavonoid that is abundant in fruits and vegetables and has protective effects against cancer and diabetes. However, the mechanism of action of myricetin against gastric cancer (GC) is not fully understood. We researched myricetin on the proliferation, apoptosis, and cell cycle in GC HGC-27 and SGC7901 cells, to explore the underlying mechanism of action. Cell Counting Kit (CCK)-8 assay, Western blotting, cell cycle analysis, and apoptosis assay were used to evaluate the effects of myricetin on cell proliferation, apoptosis, and the cell cycle. To analyze the binding properties of ribosomal S6 kinase 2 (RSK2) with myricetin, surface plasmon resonance (SPR) analysis was performed. CCK8 assay showed that myricetin inhibited GC cell proliferation. Flow cytometry analysis showed that myricetin induces apoptosis and cell cycle arrest in GC cells. Western blotting indicated that myricetin influenced apoptosis and cell cycle arrest of GC cells by regulating related proteins. SPR analysis showed strong binding affinity of RSK2 and myricetin. Myricetin bound to RSK2, leading to increased expression of Mad1, and contributed to inhibition of HGC-27 and SGC7901 cell proliferation. Our results suggest the therapeutic potential of myricetin in GC.

  20. Promoting Cell Proliferation Using Water Dispersible Germanium Nanowires

    PubMed Central

    Bezuidenhout, Michael; Liu, Pai; Singh, Shalini; Kiely, Maeve

    2014-01-01

    Group IV Nanowires have strong potential for several biomedical applications. However, to date their use remains limited because many are synthesised using heavy metal seeds and functionalised using organic ligands to make the materials water dispersible. This can result in unpredicted toxic side effects for mammalian cells cultured on the wires. Here, we describe an approach to make seedless and ligand free Germanium nanowires water dispersible using glutamic acid, a natural occurring amino acid that alleviates the environmental and health hazards associated with traditional functionalisation materials. We analysed the treated material extensively using Transmission electron microscopy (TEM), High resolution-TEM, and scanning electron microscope (SEM). Using a series of state of the art biochemical and morphological assays, together with a series of complimentary and synergistic cellular and molecular approaches, we show that the water dispersible germanium nanowires are non-toxic and are biocompatible. We monitored the behaviour of the cells growing on the treated germanium nanowires using a real time impedance based platform (xCELLigence) which revealed that the treated germanium nanowires promote cell adhesion and cell proliferation which we believe is as a result of the presence of an etched surface giving rise to a collagen like structure and an oxide layer. Furthermore this study is the first to evaluate the associated effect of Germanium nanowires on mammalian cells. Our studies highlight the potential use of water dispersible Germanium Nanowires in biological platforms that encourage anchorage-dependent cell growth. PMID:25237816

  1. Promoting cell proliferation using water dispersible germanium nanowires.

    PubMed

    Bezuidenhout, Michael; Liu, Pai; Singh, Shalini; Kiely, Maeve; Ryan, Kevin M; Kiely, Patrick A

    2014-01-01

    Group IV Nanowires have strong potential for several biomedical applications. However, to date their use remains limited because many are synthesised using heavy metal seeds and functionalised using organic ligands to make the materials water dispersible. This can result in unpredicted toxic side effects for mammalian cells cultured on the wires. Here, we describe an approach to make seedless and ligand free Germanium nanowires water dispersible using glutamic acid, a natural occurring amino acid that alleviates the environmental and health hazards associated with traditional functionalisation materials. We analysed the treated material extensively using Transmission electron microscopy (TEM), High resolution-TEM, and scanning electron microscope (SEM). Using a series of state of the art biochemical and morphological assays, together with a series of complimentary and synergistic cellular and molecular approaches, we show that the water dispersible germanium nanowires are non-toxic and are biocompatible. We monitored the behaviour of the cells growing on the treated germanium nanowires using a real time impedance based platform (xCELLigence) which revealed that the treated germanium nanowires promote cell adhesion and cell proliferation which we believe is as a result of the presence of an etched surface giving rise to a collagen like structure and an oxide layer. Furthermore this study is the first to evaluate the associated effect of Germanium nanowires on mammalian cells. Our studies highlight the potential use of water dispersible Germanium Nanowires in biological platforms that encourage anchorage-dependent cell growth.

  2. Effects of spaceflight on the proliferation of jejunal mucosal cells

    NASA Technical Reports Server (NTRS)

    Phillips, Robert W.; Moeller, C. L.; Sawyer, Heywood R.; Smirnov, K. L.

    1991-01-01

    The purpose of this project was to test the hypothesis that the generalized, whole body decrease in synthetic activity due to microgravity conditions encountered during spaceflight would be demonstrable in cells and tissues characterized by a rapid rate of turnover. Jejunal mucosal cells were chosen as a model since these cells are among the most rapidly proliferating in the body. Accordingly, the percentage of mitotic cells present in the crypts of Lieberkuhn in each of 5 rats flown on the COSMOS 2044 mission were compared to the percentage of mitotic cells present in the crypts in rats included in each of 3 ground control groups (i.e., vivarium, synchronous and caudal-elevated). No significant difference (p greater than .05) was detected in mitotic indices between the flight and vivarium group. Although the ability of jejunal mucosal cells to divide by mitosis was not impaired in flight group, there was, however, a reduction in the length of villi and depth of crypts. The concommitant reduction in villus length and crypth depth in the flight group probably reflects changes in connective tissue components within the core of villi.

  3. Annexin 2A sustains glioblastoma cell dissemination and proliferation

    PubMed Central

    Maule, Francesca; Bresolin, Silvia; Rampazzo, Elena; Boso, Daniele; Puppa, Alessandro Della; Esposito, Giovanni; Porcù, Elena; Mitola, Stefania; Lombardi, Giuseppe; Accordi, Benedetta; Tumino, Manuela; Basso, Giuseppe; Persano, Luca

    2016-01-01

    Glioblastoma (GBM) is the most devastating tumor of the brain, characterized by an almost inevitable tendency to recur after intensive treatments and a fatal prognosis. Indeed, despite recent technical improvements in GBM surgery, the complete eradication of cancer cell disseminated outside the tumor mass still remains a crucial issue for glioma patients management. In this context, Annexin 2A (ANXA2) is a phospholipid-binding protein expressed in a variety of cell types, whose expression has been recently associated with cell dissemination and metastasis in many cancer types, thus making ANXA2 an attractive putative regulator of cell invasion also in GBM. Here we show that ANXA2 is over-expressed in GBM and positively correlates with tumor aggressiveness and patient survival. In particular, we associate the expression of ANXA2 to a mesenchymal and metastatic phenotype of GBM tumors. Moreover, we functionally characterized the effects exerted by ANXA2 inhibition in primary GBM cultures, demonstrating its ability to sustain cell migration, matrix invasion, cytoskeletal remodeling and proliferation. Finally, we were able to generate an ANXA2-dependent gene signature with a significant prognostic potential in different cohorts of solid tumor patients, including GBM. In conclusion, we demonstrate that ANXA2 acts at multiple levels in determining the disseminating and aggressive behaviour of GBM cells, thus proving its potential as a possible target and strong prognostic factor in the future management of GBM patients. PMID:27429043

  4. Cefazolin Irreversibly Inhibits Proliferation and Migration of Human Mesenchymal Stromal Cells

    PubMed Central

    Pilge, Hakan; Fröbel, Julia; Lensing-Höhn, Sabine; Zilkens, Christoph; Krauspe, Rüdiger

    2016-01-01

    Drugs may have a significant effect on postoperative bone healing by reducing the function of human mesenchymal stromal cells (hMSC) or mature osteoblasts. Although cefazolin is one of the most commonly used antibiotic drugs in arthroplasty to prevent infection worldwide, there is a lack of information regarding how cefazolin affects hMSC and therefore may have an effect on early bone healing. We studied the proliferation and migration capacity of primary hMSC during cefazolin treatment at various doses for up to 3 days, as well as the reversibility of the effects during the subsequent 3 days of culture without the drug. We found a time- and dose-dependent reduction of the proliferation rate and the migratory potential. Tests of whether these effects were reversible revealed that doses ≥250 μg/mL or treatments longer than 24 h irreversibly affected the cells. We are the first to show that application of cefazolin irreversibly inhibits the potential of hMSC for migration to the trauma site and local proliferation. Cefazolin should be administered only at the required dosage and time to prevent periprosthetic infection. If long-term administration is required and delayed bone healing is present, cefazolin application must be considered as a cause of delayed bone healing. PMID:27069918

  5. p75 neurotrophin receptor is involved in proliferation of undifferentiated mouse embryonic stem cells.

    PubMed

    Moscatelli, Ilana; Pierantozzi, Enrico; Camaioni, Antonella; Siracusa, Gregorio; Campagnolo, Luisa

    2009-11-01

    Neurotrophins and their receptors are known to play a role in the proliferation and survival of many different cell types of neuronal and non-neuronal lineages. In addition, there is much evidence in the literature showing that the p75 neurotrophin receptor (p75(NTR)), alone or in association with members of the family of Trk receptors, is expressed in a wide variety of stem cells, although its role in such cells has not been completely elucidated. In the present work we have investigated the expression of p75(NTR) and Trks in totipotent and pluripotent cells, the mouse pre-implantation embryo and embryonic stem and germ cells (ES and EG cells). p75(NTR) and TrkA can be first detected in the blastocyst from which ES cell lines are derived. Mouse ES cells retain p75(NTR)/TrkA expression. Nerve growth factor is the only neurotrophin able to stimulate ES cell growth in culture, without affecting the expression of stem cell markers, alkaline phosphatase, Oct4 and Nanog. Such proliferation effect was blocked by antagonizing either p75(NTR) or TrkA. Interestingly, immunoreactivity to anti-p75(NTR) antibodies is lost upon ES cell differentiation. The expression pattern of neurotrophin receptors in murine ES cells differs from human ES cells, that only express TrkB and C, and do not respond to NGF. In this paper we also show that, while primordial germ cells (PGC) do not express p75(NTR), when they are made to revert to an ES-like phenotype, becoming EG cells, expression of p75(NTR) is turned on.

  6. p75 neurotrophin receptor is involved in proliferation of undifferentiated mouse embryonic stem cells

    SciTech Connect

    Moscatelli, Ilana; Pierantozzi, Enrico; Camaioni, Antonella; Siracusa, Gregorio; Campagnolo, Luisa

    2009-11-01

    Neurotrophins and their receptors are known to play a role in the proliferation and survival of many different cell types of neuronal and non-neuronal lineages. In addition, there is much evidence in the literature showing that the p75 neurotrophin receptor (p75{sup NTR}), alone or in association with members of the family of Trk receptors, is expressed in a wide variety of stem cells, although its role in such cells has not been completely elucidated. In the present work we have investigated the expression of p75{sup NTR} and Trks in totipotent and pluripotent cells, the mouse pre-implantation embryo and embryonic stem and germ cells (ES and EG cells). p75{sup NTR} and TrkA can be first detected in the blastocyst from which ES cell lines are derived. Mouse ES cells retain p75{sup NTR}/TrkA expression. Nerve growth factor is the only neurotrophin able to stimulate ES cell growth in culture, without affecting the expression of stem cell markers, alkaline phosphatase, Oct4 and Nanog. Such proliferation effect was blocked by antagonizing either p75{sup NTR} or TrkA. Interestingly, immunoreactivity to anti-p75{sup NTR} antibodies is lost upon ES cell differentiation. The expression pattern of neurotrophin receptors in murine ES cells differs from human ES cells, that only express TrkB and C, and do not respond to NGF. In this paper we also show that, while primordial germ cells (PGC) do not express p75{sup NTR}, when they are made to revert to an ES-like phenotype, becoming EG cells, expression of p75{sup NTR} is turned on.

  7. Effect of the chemical composition of Ricinus communis polyurethane on rat bone marrow cell attachment, proliferation, and differentiation.

    PubMed

    Beloti, Márcio M; Hiraki, Karen R N; Barros, Valdemar M R; Rosa, Adalberto L

    2003-01-01

    Alterations in the chemical composition of a polymer may be undertaken to improve its biological properties. The aim of this study was to investigate the in vitro biocompatibility of Ricinus communis polyurethane (RCP) with three different chemical compositions: RCPp (pure RCP), RCP+CaCO(3), and RCP+Ca(3)(PO(4))(2). Rat bone marrow cells were cultivated under conditions that allowed osteoblastic differentiation and were evaluated for cell attachment, cell proliferation, cell morphology, total protein content, alkaline phosphatase (ALP) activity, and bonelike nodule formation. For the evaluation of attachment, cells were cultured for 4 h. After 3 days, cell morphology was evaluated. Cell proliferation was evaluated after 7 and 14 days. Total protein content and ALP activity were evaluated after 14 days. For bonelike nodule formation, cells were cultured for 21 days. Data were compared with an analysis of variance and Duncan's multiple range test when appropriate. Cell attachment and ALP activity were not affected by RCP chemical composition. Proliferation, total protein content, and bonelike nodule formation were all affected by RCP chemical composition. These results suggest that initial cell events are not affected by RCP chemical composition, whereas RCPs blended with calcium carbonate or, better yet, calcium phosphate, by favoring events that promote matrix mineralization, are more biocompatible materials.

  8. Syndecan-1 responsive microRNA-126 and 149 regulate cell proliferation in prostate cancer

    SciTech Connect

    Fujii, Tomomi; Shimada, Keiji; Tatsumi, Yoshihiro; Fujimoto, Kiyohide; Konishi, Noboru

    2015-01-02

    Highlights: • Syndecan-1 is highly expressed in androgen independent prostate cancer cells, PC3. • Syndecan-1 regulates the expression of miR-126 and -149 in prostate cancer cells. • MiR-126 and 149 control cell growth via p21 induction and senescence mechanism. • MiR-126 and 149 promote cell proliferation by suppressing SOX2, NANOG, and Oct4. - Abstract: MicroRNAs (miRNAs) are short (19–24 nt), low molecular weight RNAs that play important roles in the regulation of target genes associated with cell proliferation, differentiation, and development, by binding to the 3′-untranslated region of the target mRNAs. In this study, we examined the expression of miRNA-126 (miR-126) and miR-149 in prostate cancer, and investigated the molecular mechanisms by which they affect syndecan-1 in prostate cancer. Functional analysis of miR-126 and miR-149 was conducted in the prostate cancer cell lines, PC3, Du145, and LNCaP. The expression levels of SOX2, NANOG, Oct4, miR-126 and miR-149 were evaluated by quantitative RT-PCR. After silencing syndecan-1, miR-126, and/or miR-149 in the PC3 cells, cell proliferation, senescence, and p21 induction were assessed using the MTS assay, senescence-associated β-galactosidase (SA-β-Gal) assay, and immunocytochemistry, respectively. Compared to the Du145 and LNCaP cells, PC3 cells exhibited higher expression of syndecan-1. When syndecan-1 was silenced, the PC3 cells showed reduced expression of miR-126 and miR-149 most effectively. Suppression of miR-126 and/or miR-149 significantly inhibited cell growth via p21 induction and subsequently, induced senescence. The mRNA expression levels of SOX2, NANOG, and Oct4 were significantly increased in response to the silencing of miR-126 and/or miR-149. Our results suggest that miR-126 and miR-149 are associated with the expression of syndecan-1 in prostate cancer cells. These miRNAs promote cell proliferation by suppressing SOX2, NANOG, and Oct4. The regulation of these factors by mi

  9. Maslinic Acid Inhibits Proliferation of Renal Cell Carcinoma Cell Lines and Suppresses Angiogenesis of Endothelial Cells

    PubMed Central

    Thakor, Parth; Song, Wenzhe; Subramanian, Ramalingam B.; Thakkar, Vasudev R.; Vesey, David A.

    2017-01-01

    Despite the introduction of many novel therapeutics in clinical practice, metastatic renal cell carcinoma (RCC) remains a treatment-resistant cancer. As red and processed meat are considered risk factors for RCC, and a vegetable-rich diet is thought to reduce this risk, research into plant-based therapeutics may provide valuable complementary or alternative therapeutics for the management of RCC. Herein, we present the antiproliferative and antiangiogenic effects of maslinic acid, which occurs naturally in edible plants, particularly in olive fruits, and also in a variety of medicinal plants. Human RCC cell lines (ACHN, Caki-1, and SN12K1), endothelial cells (human umbilical vein endothelial cell line [HUVEC]), and primary cultures of kidney proximal tubular epithelial cells (PTEC) were treated with maslinic acid. Maslinic acid was relatively less toxic to PTEC when compared with RCC under similar experimental conditions. In RCC cell lines, maslinic acid induced a significant reduction in proliferation, proliferating cell nuclear antigen, and colony formation. In HUVEC, maslinic acid induced a significant reduction in capillary tube formation in vitro and vascular endothelial growth factor. This study provides a rationale for incorporating a maslinic acid–rich diet either to reduce the risk of developing kidney cancer or as an adjunct to existing antiangiogenic therapy to improve efficacy.

  10. NSA2, a novel nucleolus protein regulates cell proliferation and cell cycle

    SciTech Connect

    Zhang, Heyu; Ma, Xi; Shi, Taiping; Song, Quansheng; Zhao, Hongshan; Ma, Dalong

    2010-01-01

    NSA2 (Nop seven-associated 2) was previously identified in a high throughput screen of novel human genes associated with cell proliferation, and the NSA2 protein is evolutionarily conserved across different species. In this study, we revealed that NSA2 is broadly expressed in human tissues and cultured cell lines, and located in the nucleolus of the cell. Both of the putative nuclear localization signals (NLSs) of NSA2, also overlapped with nucleolar localization signals (NoLSs), are capable of directing nucleolar accumulation. Moreover, over-expression of the NSA2 protein promoted cell growth in different cell lines and regulated the G1/S transition in the cell cycle. SiRNA silencing of the NSA2 transcript attenuated the cell growth and dramatically blocked the cell cycle in G1/S transition. Our results demonstrated that NSA2 is a nucleolar protein involved in cell proliferation and cell cycle regulation.

  11. Effects of retinol on proliferation, cell adherence and extracellular matrix synthesis in a liver myofibroblast or lipocyte cell line (GRX).

    PubMed Central

    Margis, R.; Pinheiro-Margis, M.; da Silva, L. C.; Borojevic, R.

    1992-01-01

    We have studied the effect of retinol on an established murine cell line (GRX), representative of liver connective tissue cells. This cell line has myofibroblast characteristics; under retinol treatment it is induced into the lipocyte (Ito-cell) phenotype. Retinol decreased the proliferation rate in the entire cell population. It increased cell adherence to the substrate, which was correlated with the increased secretion of fibronectin. Collagen secretion was specifically decreased, whilst the total protein secretion remained stable. Heparan sulphate was decreased in the pericellular compartment, but other glycosaminoglycans were not affected by retinol treatment. Modulations of pericellular components induced by retinol may alter the relations among liver mesenchymal cells, and may be related to vitamin-A-induced modifications of the homoeostasis of hepatic connective tissue and hepatic fibrosis. Images Fig. 6 PMID:1571273

  12. Nuclear distribution of claudin-2 increases cell proliferation in human lung adenocarcinoma cells.

    PubMed

    Ikari, Akira; Watanabe, Ryo; Sato, Tomonari; Taga, Saeko; Shimobaba, Shun; Yamaguchi, Masahiko; Yamazaki, Yasuhiro; Endo, Satoshi; Matsunaga, Toshiyuki; Sugatani, Junko

    2014-09-01

    Claudin-2 is expressed in human lung adenocarcinoma tissue and cell lines, although it is absent in normal lung tissue. However, the role of claudin-2 in cell proliferation and the regulatory mechanism of intracellular distribution remain undefined. Proliferation of human adenocarcinoma A549 cells was decreased by claudin-2 knockdown together with a decrease in the percentage of S phase cells. This knockdown decreased the expression levels of ZONAB and cell cycle regulators. Claudin-2 was distributed in the nucleus in human adenocarcinoma tissues and proliferating A549 cells. The nuclear distribution of ZONAB and percentage of S phase cells were higher in cells exogenously expressing claudin-2 with a nuclear localization signal than in cells expressing claudin-2 with a nuclear export signal. Nuclear claudin-2 formed a complex with ZO-1, ZONAB, and cyclin D1. Nuclear distribution of S208A mutant, a dephosphorylated form of claudin-2, was higher than that of wild type. We suggest that nuclear distribution of claudin-2 is up-regulated by dephosphorylation and claudin-2 serves to retain ZONAB and cyclin D1 in the nucleus, resulting in the enhancement of cell proliferation in lung adenocarcinoma cells.

  13. XB130 promotes bronchioalveolar stem cell and Club cell proliferation in airway epithelial repair and regeneration

    PubMed Central

    Toba, Hiroaki; Wang, Yingchun; Bai, Xiaohui; Zamel, Ricardo; Cho, Hae-Ra; Liu, Hongmei; Lira, Alonso; Keshavjee, Shaf; Liu, Mingyao

    2015-01-01

    Proliferation of bronchioalveolar stem cells (BASCs) is essential for epithelial repair. XB130 is a novel adaptor protein involved in the regulation of epithelial cell survival, proliferation and migration through the PI3K/Akt pathway. To determine the role of XB130 in airway epithelial injury repair and regeneration, a naphthalene-induced airway epithelial injury model was used with XB130 knockout (KO) mice and their wild type (WT) littermates. In XB130 KO mice, at days 7 and 14, small airway epithelium repair was significantly delayed with fewer number of Club cells (previously called Clara cells). CCSP (Club cell secreted protein) mRNA expression was also significantly lower in KO mice at day 7. At day 5, there were significantly fewer proliferative epithelial cells in the KO group, and the number of BASCs significantly increased in WT mice but not in KO mice. At day 7, phosphorylation of Akt, GSK-3β, and the p85α subunit of PI3K was observed in airway epithelial cells in WT mice, but to a much lesser extent in KO mice. Microarray data also suggest that PI3K/Akt-related signals were regulated differently in KO and WT mice. An inhibitory mechanism for cell proliferation and cell cycle progression was suggested in KO mice. XB130 is involved in bronchioalveolar stem cell and Club cell proliferation, likely through the PI3K/Akt/GSK-3β pathway. PMID:26360608

  14. Influence of Flow Behavior of Alginate-Cell Suspensions on Cell Viability and Proliferation.

    PubMed

    Ning, Liqun; Guillemot, Arthur; Zhao, Jingxuan; Kipouros, Georges; Chen, Xiongbiao

    2016-07-01

    Tissue scaffolds with living cells fabricated by three-dimensional bioprinting/plotting techniques are becoming more prevalent in tissue repair and regeneration. In the bioprinting process, cells are subject to process-induced forces (such as shear force) that can result in cell damage and loss of cell function. The flow behavior of the biomaterial solutions that encapsulate living cells in this process plays an important role. This study used a rheometer to examine the flow behavior of alginate solution and alginate-Schwann cell (RSC96), alginate-fibroblast cell (NIH-3T3), and alginate-skeletal muscle cell (L8) suspensions during shearing with respect to effects on cell viability and proliferation. The flow behavior of all the alginate-cell suspensions varied with alginate concentration and cell density and had a significant influence on the viability and proliferation of the cells once sheared as well as on the recovery of the sheared cells. These findings provide a mean to preserve cell viability and/or retain cell proliferation function in the bioprinting process by regulating the flow behavior of cell-biomaterial suspensions and process parameters.

  15. Circadian variation of cell proliferation in HTR-8/SVneo cell line.

    PubMed

    Lunghi, Laura; Frigato, Elena; Ferretti, Maria Enrica; Biondi, Carla; Bertolucci, Cristiano

    2011-12-01

    Circadian clock controls several physiological processes such as cell proliferation. Extravillous trophoblast proliferation is a tightly regulated function playing a fundamental role in maternal vessel remodeling. We recently demonstrated that clock genes Per2 and Dec1 as well as the clock-controlled genes Dbp and Vegf are rhythmically expressed in human extravillous trophoblast-derived HTR-8/SVneo cells. Analyzing the time course of HTR-8/SVneo cell proliferation, a circadian variation in cell number was found. Moreover, we showed a rhythmic expression of mRNAs for Wee1 and stathmin, two genes involved in cell cycle progression. We suggest that circadian clockwork may orchestrate the functionality of the several factors involved in the control of human trophoblast functions that are fundamental for a successfully pregnancy outcome.

  16. A sharp T-cell antigen receptor signaling threshold for T-cell proliferation

    PubMed Central

    Au-Yeung, Byron B.; Zikherman, Julie; Mueller, James L.; Ashouri, Judith F.; Matloubian, Mehrdad; Cheng, Debra A.; Chen, Yiling; Shokat, Kevan M.; Weiss, Arthur

    2014-01-01

    T-cell antigen receptor (TCR) signaling is essential for activation, proliferation, and effector function of T cells. Modulation of both intensity and duration of TCR signaling can regulate these events. However, it remains unclear how individual T cells integrate such signals over time to make critical cell-fate decisions. We have previously developed an engineered mutant allele of the critical T-cell kinase zeta-chain-associated protein kinase 70 kDa (Zap70) that is catalytically inhibited by a small molecule inhibitor, thereby blocking TCR signaling specifically and efficiently. We have also characterized a fluorescent reporter Nur77–eGFP transgenic mouse line in which T cells up-regulate GFP uniquely in response to TCR stimulation. The combination of these technologies unmasked a sharp TCR signaling threshold for commitment to cell division both in vitro and in vivo. Further, we demonstrate that this threshold is independent of both the magnitude of the TCR stimulus and Interleukin 2. Similarly, we identify a temporal threshold of TCR signaling that is required for commitment to proliferation, after which T cells are able to proliferate in a Zap70 kinase-independent manner. Taken together, our studies reveal a sharp threshold for the magnitude and duration of TCR signaling required for commitment of T cells to proliferation. These results have important implications for understanding T-cell responses to infection and optimizing strategies for immunomodulatory drug delivery. PMID:25136127

  17. Butyl benzyl phthalate suppresses the ATP-induced cell proliferation in human osteosarcoma HOS cells

    SciTech Connect

    Liu, P.-S.; Chen, C.-Y.

    2010-05-01

    Butyl benzyl phthalate (BBP), an endocrine disruptor present in the environment, exerts its genomic effects via intracellular steroid receptors and elicits non-genomic effects by interfering with membrane ion-channel receptors. We previously found that BBP blocks the calcium signaling coupled with P2X receptors in PC12 cells (Liu and Chen, 2006). Osteoblast P2X receptors were recently reported to play a role in cell proliferation and bone remodeling. In this present study, the effects of BBP on ATP-induced responses were investigated in human osteosarcoma HOS cells. These receptors mRNA had been detected, named P2X4, P2X7, P2Y2, P2Y4, P2Y5, P2Y9, and P2Y11, in human osteosarcoma HOS cells by RT-PCR. The enhancement of cell proliferation and the decrease of cytoviability had both been shown to be coupled to stimulation via different concentrations of ATP. BBP suppressed the ATP-induced calcium influx (mainly coupled with P2X) and cell proliferation but not the ATP-induced intracellular calcium release (mainly coupled with P2Y) and cytotoxicity in human osteosarcoma HOS cells. Suramin, a common P2 receptor's antagonist, blocked the ATP-induced calcium signaling, cell proliferation, and cytotoxicity. We suggest that P2X is mainly responsible for cell proliferation, and P2Y might be partially responsible for the observed cytotoxicity. BBP suppressed the calcium signaling coupled with P2X, suppressing cell proliferation. Since the importance of P2X receptors during bone metastasis has recently become apparent, the possible toxic risk of environmental BBP during bone remodeling is a public problem of concern.

  18. Xenobiotic effects on intestinal stem cell proliferation in adult honey bee (Apis mellifera L) workers.

    PubMed

    Forkpah, Cordelia; Dixon, Luke R; Fahrbach, Susan E; Rueppell, Olav

    2014-01-01

    The causes of the current global decline in honey bee health are unknown. One major group of hypotheses invokes the pesticides and other xenobiotics to which this important pollinator species is often exposed. Most studies have focused on mortality or behavioral deficiencies in exposed honey bees while neglecting other biological functions and target organs. The midgut epithelium of honey bees presents an important interface between the insect and its environment. It is maintained by proliferation of intestinal stem cells throughout the adult life of honey bees. We used caged honey bees to test multiple xenobiotics for effects on the replicative activity of the intestinal stem cells under laboratory conditions. Most of the tested compounds did not alter the replicative activity of intestinal stem cells. However, colchicine, methoxyfenozide, tetracycline, and a combination of coumaphos and tau-fluvalinate significantly affected proliferation rate. All substances except methoxyfenozide decreased proliferation rate. Thus, the results indicate that some xenobiotics frequently used in apiculture and known to accumulate in honey bee hives may have hitherto unknown physiological effects. The nutritional status and the susceptibility to pathogens of honey bees could be compromised by the impacts of xenobiotics on the maintenance of the midgut epithelium. This study contributes to a growing body of evidence that more comprehensive testing of xenobiotics may be required before novel or existing compounds can be considered safe for honey bees and other non-target species.

  19. Xenobiotic Effects on Intestinal Stem Cell Proliferation in Adult Honey Bee (Apis mellifera L) Workers

    PubMed Central

    Forkpah, Cordelia; Dixon, Luke R.; Fahrbach, Susan E.; Rueppell, Olav

    2014-01-01

    The causes of the current global decline in honey bee health are unknown. One major group of hypotheses invokes the pesticides and other xenobiotics to which this important pollinator species is often exposed. Most studies have focused on mortality or behavioral deficiencies in exposed honey bees while neglecting other biological functions and target organs. The midgut epithelium of honey bees presents an important interface between the insect and its environment. It is maintained by proliferation of intestinal stem cells throughout the adult life of honey bees. We used caged honey bees to test multiple xenobiotics for effects on the replicative activity of the intestinal stem cells under laboratory conditions. Most of the tested compounds did not alter the replicative activity of intestinal stem cells. However, colchicine, methoxyfenozide, tetracycline, and a combination of coumaphos and tau-fluvalinate significantly affected proliferation rate. All substances except methoxyfenozide decreased proliferation rate. Thus, the results indicate that some xenobiotics frequently used in apiculture and known to accumulate in honey bee hives may have hitherto unknown physiological effects. The nutritional status and the susceptibility to pathogens of honey bees could be compromised by the impacts of xenobiotics on the maintenance of the midgut epithelium. This study contributes to a growing body of evidence that more comprehensive testing of xenobiotics may be required before novel or existing compounds can be considered safe for honey bees and other non-target species. PMID:24608542

  20. Periodontitis promotes the proliferation and suppresses the differentiation potential of human periodontal ligament stem cells.

    PubMed

    Zheng, Wei; Wang, Shi; Wang, Jianguo; Jin, Fang

    2015-10-01

    The aim of the present study was to investigate the periodontitis-associated changes in the number, proliferation and differentiation potential of human periodontal ligament stem cells (PDLSCs). Cultures of human periodontal ligament cells (PDLCs) were established from healthy donors and donors with periodontitis. The numbers of stem cell were characterized using flow cytometry. PDLSCs were isolated from the PDLCs by immunomagnetic bead selection. Colony‑forming abilities, osteogenic and adipogenic potential, gene expression of cementoblast phenotype, alkaline phosphatase activity and in vivo differentiation capacities were then evaluated. Periodontitis caused an increase in the proliferation of PDLSCs and a decrease in the commitment to the osteoblast lineage. This is reflected by changes in the expression of osteoblast markers. When transplanted into immunocompromised mice, PDLSCs from the healthy donors exhibited the capacity to produce cementum PDL‑like structures, whereas, the inflammatory PDLSCs transplants predominantly formed connective tissues. In conclusion, the data from the present study suggest that periodontitis affects the proliferation and differentiation potential of human PDLSCs in vitro and in vivo.

  1. Diffuse and uncontrolled vascular smooth muscle cell proliferation in rapidly progressing pediatric moyamoya disease.

    PubMed

    Reid, Amy J; Bhattacharjee, Meenakshi B; Regalado, Ellen S; Milewicz, Allen L; El-Hakam, Lisa M; Dauser, Robert C; Milewicz, Dianna M

    2010-09-01

    Moyamoya disease is a rare stroke syndrome of unknown etiology resulting from stenosis or occlusion of the supraclinoid internal carotid artery (ICA) in association with an abnormal vascular network in the basal ganglia. Although the highest incidence of moyamoya disease is in pediatric patients, pathology reports have been primarily limited to adult samples and describe occlusive fibrocellular lesions in the intimae of affected arteries. We describe the case of a young girl with primary moyamoya disease who presented at 18 months of age with right hemiparesis following an ischemic stroke. Angiography showed stenosis of the distal left ICA, left middle cerebral artery, and right ICA. An emergent left-sided dural inversion was performed. Recurrent strokes and alternating hemiplegia necessitated a right dural inversion 6 months later. Nonetheless, her aggressive disease proved uniquely refractory to surgical revascularization, and she succumbed to recurrent strokes and neurological deterioration at 2.5 years of age. Pathological specimens revealed a striking bilateral occlusion of the anterior carotid circulation resulting from intimal proliferation of smooth muscle cells (SMCs). Most strikingly, the ascending aorta and the superior mesenteric artery demonstrated similar intimal proliferation, along with SMC proliferation in the media. The systemic pathology involving multiple arteries in this extremely young child, the first case of its kind available for autopsy, suggests that globally uncontrolled SMC proliferation, in the absence of environmental risk factors and likely resulting from an underlying genetic alteration, may be a primary etiologic event leading to moyamoya disease.

  2. Different Culture Media Affect Proliferation, Surface Epitope Expression, and Differentiation of Ovine MSC

    PubMed Central

    Tolba, René; Jahnen-Dechent, Wilhelm; Lethaus, Bernd; Neuss, Sabine

    2013-01-01

    Orthopedic implants including engineered bone tissue are commonly tested in sheep. To avoid rejection of heterologous or xenogeneic cells, autologous cells are preferably used, that is, ovine mesenchymal stem cells (oMSC). Unlike human MSC, ovine MSC are not well studied regarding isolation, expansion, and characterization. Here we investigated the impact of culture media composition on growth characteristics, differentiation, and surface antigen expression of oMSC. The culture media varied in fetal calf serum (FCS) content and in the addition of supplements and/or additional epidermal growth factor (EGF). We found that FCS strongly influenced oMSC proliferation and that specific combinations of supplemental factors (MCDB-201, ITS-plus, dexamethasone, and L-ascorbic acid) determined the expression of surface epitopes. We compared two published protocols for oMSC differentiation towards the osteogenic, adipogenic, and chondrogenic fate and found (i) considerable donor to donor variations, (ii) protocol-dependent variations, and (iii) variations resulting from the preculture medium composition. Our results indicate that the isolation and culture of oMSC in different growth media are highly variable regarding oMSC phenotype and behaviour. Furthermore, variations from donor to donor critically influence growth rate, surface marker expression, and differentiation. PMID:24228035

  3. Effect of surface potential on epithelial cell adhesion, proliferation and morphology.

    PubMed

    Chang, Hsun-Yun; Kao, Wei-Lun; You, Yun-Wen; Chu, Yi-Hsuan; Chu, Kuo-Jui; Chen, Peng-Jen; Wu, Chen-Yi; Lee, Yu-Hsuan; Shyue, Jing-Jong

    2016-05-01

    Cell adhesion is the basis of individual cell survival, division and motility. Hence, understanding the effects that the surface properties have on cell adhesion, proliferation and morphology are crucial. In particular, surface charge/potential has been identified as an important factor that affects cell behavior. However, how cells respond to incremental changes in surface potential remains unclear. By using binary self-assembled monolayer (SAM) modified Au surfaces that are similar in mechanical/chemical properties and provide a series of surface potentials, the effect of surface potential on the behavior of cells can be studied. In this work, the effect of surface potential on epithelial cells, including human embryonic kidney (HEK293T) and human hepatocellular carcinoma (HepG2), were examined. The results showed that the adhesion density of epithelial cells increased with increasing surface potential, which is similar to but varied more significantly compared with fibroblasts. The proliferation rate is found to be independent of surface potential in both cell types. Furthermore, epithelial cells show no morphological change with respect to surface potential, whereas the morphology of the fibroblasts clearly changed with the surface potential. These differences between the cell types were rationalized by considering the difference in extracellul