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Sample records for abnormal cell proliferation

  1. NKCC1-Deficiency Results in Abnormal Proliferation of Neural Progenitor Cells of the Lateral Ganglionic Eminence.

    PubMed

    Magalhães, Ana Cathia; Rivera, Claudio

    2016-01-01

    The proliferative pool of neural progenitor cells is maintained by exquisitely controlled mechanisms for cell cycle regulation. The Na-K-Cl cotransporter (NKCC1) is important for regulating cell volume and the proliferation of different cell types in vitro. NKCC1 is expressed in ventral telencephalon of embryonic brains suggesting a potential role in neural development of this region. The ventral telencephalon is a major source for both interneuron and oligodendrocyte precursor cells. Whether NKCC1 is involved in the proliferation of these cell populations remains unknown. In order to assess this question, we monitored several markers for neural, neuronal, and proliferating cells in wild-type (WT) and NKCC1 knockout (KO) mouse brains. We found that NKCC1 was expressed in neural progenitor cells from the lateral ganglionic eminence (LGE) at E12.5. Mice lacking NKCC1 expression displayed reduced phospho-Histone H3 (PH3)-labeled mitotic cells in the ventricular zone (VZ) and reduced cell cycle reentry. Accordingly, we found a significant reduction of Sp8-labeled immature interneurons migrating from the dorsal LGE in NKCC1-deficient mice at a later developmental stage. Interestingly, at E14.5, NKCC1 regulated also the formation of Olig2-labeled oligodendrocyte precursor cells. Collectively, these findings show that NKCC1 serves in vivo as a modulator of the cell cycle decision in the developing ventral telencephalon at the early stage of neurogenesis. These results present a novel mechanistic avenue to be considered in the recent proposed involvement of chloride transporters in a number of developmentally related diseases, such as epilepsy, autism, and schizophrenia. PMID:27582690

  2. NKCC1-Deficiency Results in Abnormal Proliferation of Neural Progenitor Cells of the Lateral Ganglionic Eminence

    PubMed Central

    Magalhães, Ana Cathia; Rivera, Claudio

    2016-01-01

    The proliferative pool of neural progenitor cells is maintained by exquisitely controlled mechanisms for cell cycle regulation. The Na-K-Cl cotransporter (NKCC1) is important for regulating cell volume and the proliferation of different cell types in vitro. NKCC1 is expressed in ventral telencephalon of embryonic brains suggesting a potential role in neural development of this region. The ventral telencephalon is a major source for both interneuron and oligodendrocyte precursor cells. Whether NKCC1 is involved in the proliferation of these cell populations remains unknown. In order to assess this question, we monitored several markers for neural, neuronal, and proliferating cells in wild-type (WT) and NKCC1 knockout (KO) mouse brains. We found that NKCC1 was expressed in neural progenitor cells from the lateral ganglionic eminence (LGE) at E12.5. Mice lacking NKCC1 expression displayed reduced phospho-Histone H3 (PH3)-labeled mitotic cells in the ventricular zone (VZ) and reduced cell cycle reentry. Accordingly, we found a significant reduction of Sp8-labeled immature interneurons migrating from the dorsal LGE in NKCC1-deficient mice at a later developmental stage. Interestingly, at E14.5, NKCC1 regulated also the formation of Olig2-labeled oligodendrocyte precursor cells. Collectively, these findings show that NKCC1 serves in vivo as a modulator of the cell cycle decision in the developing ventral telencephalon at the early stage of neurogenesis. These results present a novel mechanistic avenue to be considered in the recent proposed involvement of chloride transporters in a number of developmentally related diseases, such as epilepsy, autism, and schizophrenia. PMID:27582690

  3. Abnormalities in iNKT cells are associated with impaired ability of monocytes to produce IL-10 and suppress T-cell proliferation in sarcoidosis.

    PubMed

    Crawshaw, Anjali; Kendrick, Yvonne R; McMichael, Andrew J; Ho, Ling-Pei

    2014-07-01

    Sarcoidosis is a multisystem granulomatous disorder characterized by marked T-cell expansion of T helper 1 (Th1) cells. The cause of T-cell overactivity is unknown. We hypothesized that interleukin-10 (IL-10) production by a yet undefined cell type might be defective, resulting in loss of regulation of T-cell activity. Focusing on IL-10-producing monocytes, we first showed that monocytes isolated from the peripheral blood of corticosteroid-naïve sarcoidosis patients (n = 51) produced less IL-10 compared to controls, and were less able to suppress T-cell proliferation. In addition, monocytic IL-10 production correlated negatively with disease activity score. As invariant natural killer T (iNKT) cells are known to both interact with monocytes and be reduced in sarcoidosis patients, we then asked whether iNKT-specific defects might be responsible for this reduced IL-10 production. We found that greater numbers of circulating iNKT cells was associated with higher IL-10 production. Moreover, iNKT cells enhanced monocytic IL-10 production in vitro. Defective IL-10 production and T-cell suppression by sarcoidosis monocytes could be restored following their coculture with iNKT cells, in a CD1d- and cell contact-dependent process. We suggest that reduced iNKT-cell numbers in sarcoidosis may lead to impaired monocytic IL-10 production and unchecked T-cell expansion in sarcoidosis. These findings provide fresh insight into the mechanism of sarcoidosis disease, and interaction between iNKT cells and monocytes. PMID:24723379

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

    PubMed

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

    2010-10-01

    Cystic ovarian disease (COD) is an important cause of infertility that affects cattle. Alterations in the ovarian micro-environment of females with follicular cysts could alter the normal processes of proliferation and programmed cell death in ovarian cells. Thus, the objective in the present study was to evaluate apoptosis and proliferation in induced ovarian cystic follicles in cows to investigate the follicular persistence. Stage of estrous cycle was synchronized in 10 heifers and 5 were then subjected to the induction of COD by administration of ACTH. After the ovariectomy number of in situ apoptotic cells by TUNEL assay, active caspase-3, FAS/FASLG and members of the BCL2 family were compared by immunohistochemistry and multiplex PCR and cell proliferation by evaluation of Ki-67 protein and cyclin D1 and E mRNA. Significantly (p<0.05) lesser proliferative and apoptotic rates were found in cystic follicles from cows with COD compared with those with regular cycles. The relatively minimal proliferation found by immunohistochemistry with Ki-67 marker were confirmed by the gene expression of cyclin D1 and E. Lesser apoptotic rates were associated with decreased amounts of apoptotic-related proteins BAX, FASLG and caspase-3 as well as the in situ apoptosis detected by TUNEL assay, and increased amounts of the anti-apoptotic survival factor cellular BCL2 in the cystic follicles of the COD group. The BAX/BCL2 gene expression profile confirmed the immunohistochemical findings. Results from the present study indicate that cellular proliferation and apoptosis are altered in cystic follicles of cattle. The present study provides new insights into the molecular mechanisms underlying the aberrant persistence of follicular cysts and related diseases. PMID:20800980

  5. Cell Proliferation in Neuroblastoma.

    PubMed

    Stafman, Laura L; Beierle, Elizabeth A

    2016-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed. PMID:26771642

  6. Cell Proliferation in Neuroblastoma

    PubMed Central

    Stafman, Laura L.; Beierle, Elizabeth A.

    2016-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed. PMID:26771642

  7. A Novel p38 Mitogen-activated Protein Kinase/Elk-1 Transcription Factor-dependent Molecular Mechanism Underlying Abnormal Endothelial Cell Proliferation in Plexogenic Pulmonary Arterial Hypertension*

    PubMed Central

    Patel, Monal; Predescu, Dan; Tandon, Rajive; Bardita, Cristina; Pogoriler, Jennifer; Bhorade, Sangeeta; Wang, Minhua; Comhair, Suzy; Ryan-Hemnes, Anna; Chen, Jiwang; Machado, Roberto; Husain, Aliya; Erzurum, Serpil; Predescu, Sanda

    2013-01-01

    Plexiform lesions (PLs), the hallmark of plexogenic pulmonary arterial hypertension (PAH), contain phenotypically altered, proliferative endothelial cells (ECs). The molecular mechanism that contributes to EC proliferation and formation of PLs is poorly understood. We now show that a decrease in intersectin-1s (ITSN-1s) expression due to granzyme B (GrB) cleavage during inflammation associated with PAH and the high p38/Erk1/2MAPK activity ratio caused by the GrB/ITSN cleavage products lead to EC proliferation and selection of a proliferative/plexiform EC phenotype. We used human pulmonary artery ECs of PAH subjects (ECPAH), paraffin-embedded and frozen human lung tissue, and animal models of PAH in conjunction with microscopy imaging, biochemical, and molecular biology approaches to demonstrate that GrB cleaves ITSN-1s, a prosurvival protein of lung ECs, and generates two biologically active fragments, an N-terminal fragment (GrB-EHITSN) with EC proliferative potential and a C-terminal product with dominant negative effects on Ras/Erk1/2. The proliferative potential of GrB-EHITSN is mediated via sustained phosphorylation of p38MAPK and Elk-1 transcription factor and abolished by chemical inhibition of p38MAPK. Moreover, lung tissue of PAH animal models and human specimens and ECPAH express lower levels of ITSN-1s compared with controls and the GrB-EHITSN cleavage product. Moreover, GrB immunoreactivity is associated with PLs in PAH lungs. The concurrent expression of the two cleavage products results in a high p38/Erk1/2MAPK activity ratio, which is critical for EC proliferation. Our findings identify a novel GrB-EHITSN-dependent pathogenic p38MAPK/Elk-1 signaling pathway involved in the poorly understood process of PL formation in severe PAH. PMID:23893408

  8. A novel p38 mitogen-activated protein kinase/Elk-1 transcription factor-dependent molecular mechanism underlying abnormal endothelial cell proliferation in plexogenic pulmonary arterial hypertension.

    PubMed

    Patel, Monal; Predescu, Dan; Tandon, Rajive; Bardita, Cristina; Pogoriler, Jennifer; Bhorade, Sangeeta; Wang, Minhua; Comhair, Suzy; Hemnes, Anna Ryan; Ryan-Hemnes, Anna; Chen, Jiwang; Machado, Roberto; Husain, Aliya; Erzurum, Serpil; Predescu, Sanda

    2013-09-01

    Plexiform lesions (PLs), the hallmark of plexogenic pulmonary arterial hypertension (PAH), contain phenotypically altered, proliferative endothelial cells (ECs). The molecular mechanism that contributes to EC proliferation and formation of PLs is poorly understood. We now show that a decrease in intersectin-1s (ITSN-1s) expression due to granzyme B (GrB) cleavage during inflammation associated with PAH and the high p38/Erk1/2(MAPK) activity ratio caused by the GrB/ITSN cleavage products lead to EC proliferation and selection of a proliferative/plexiform EC phenotype. We used human pulmonary artery ECs of PAH subjects (EC(PAH)), paraffin-embedded and frozen human lung tissue, and animal models of PAH in conjunction with microscopy imaging, biochemical, and molecular biology approaches to demonstrate that GrB cleaves ITSN-1s, a prosurvival protein of lung ECs, and generates two biologically active fragments, an N-terminal fragment (GrB-EH(ITSN)) with EC proliferative potential and a C-terminal product with dominant negative effects on Ras/Erk1/2. The proliferative potential of GrB-EH(ITSN) is mediated via sustained phosphorylation of p38(MAPK) and Elk-1 transcription factor and abolished by chemical inhibition of p38(MAPK). Moreover, lung tissue of PAH animal models and human specimens and EC(PAH) express lower levels of ITSN-1s compared with controls and the GrB-EH(ITSN) cleavage product. Moreover, GrB immunoreactivity is associated with PLs in PAH lungs. The concurrent expression of the two cleavage products results in a high p38/Erk1/2(MAPK) activity ratio, which is critical for EC proliferation. Our findings identify a novel GrB-EH(ITSN)-dependent pathogenic p38(MAPK)/Elk-1 signaling pathway involved in the poorly understood process of PL formation in severe PAH. PMID:23893408

  9. Meclozine Facilitates Proliferation and Differentiation of Chondrocytes by Attenuating Abnormally Activated FGFR3 Signaling in Achondroplasia

    PubMed Central

    Matsushita, Masaki; Kitoh, Hiroshi; Ohkawara, Bisei; Mishima, Kenichi; Kaneko, Hiroshi; Ito, Mikako; Masuda, Akio; Ishiguro, Naoki; Ohno, Kinji

    2013-01-01

    Achondroplasia (ACH) is one of the most common skeletal dysplasias with short stature caused by gain-of-function mutations in FGFR3 encoding the fibroblast growth factor receptor 3. We used the drug repositioning strategy to identify an FDA-approved drug that suppresses abnormally activated FGFR3 signaling in ACH. We found that meclozine, an anti-histamine drug that has long been used for motion sickness, facilitates chondrocyte proliferation and mitigates loss of extracellular matrix in FGF2-treated rat chondrosarcoma (RCS) cells. Meclozine also ameliorated abnormally suppressed proliferation of human chondrosarcoma (HCS-2/8) cells that were infected with lentivirus expressing constitutively active mutants of FGFR3-K650E causing thanatophoric dysplasia, FGFR3-K650M causing SADDAN, and FGFR3-G380R causing ACH. Similarly, meclozine alleviated abnormally suppressed differentiation of ATDC5 chondrogenic cells expressing FGFR3-K650E and -G380R in micromass culture. We also confirmed that meclozine alleviates FGF2-mediated longitudinal growth inhibition of embryonic tibia in bone explant culture. Interestingly, meclozine enhanced growth of embryonic tibia in explant culture even in the absence of FGF2 treatment. Analyses of intracellular FGFR3 signaling disclosed that meclozine downregulates phosphorylation of ERK but not of MEK in FGF2-treated RCS cells. Similarly, meclozine enhanced proliferation of RCS cells expressing constitutively active mutants of MEK and RAF but not of ERK, which suggests that meclozine downregulates the FGFR3 signaling by possibly attenuating ERK phosphorylation. We used the C-natriuretic peptide (CNP) as a potent inhibitor of the FGFR3 signaling throughout our experiments, and found that meclozine was as efficient as CNP in attenuating the abnormal FGFR3 signaling. We propose that meclozine is a potential therapeutic agent for treating ACH and other FGFR3-related skeletal dysplasias. PMID:24324705

  10. Meclozine facilitates proliferation and differentiation of chondrocytes by attenuating abnormally activated FGFR3 signaling in achondroplasia.

    PubMed

    Matsushita, Masaki; Kitoh, Hiroshi; Ohkawara, Bisei; Mishima, Kenichi; Kaneko, Hiroshi; Ito, Mikako; Masuda, Akio; Ishiguro, Naoki; Ohno, Kinji

    2013-01-01

    Achondroplasia (ACH) is one of the most common skeletal dysplasias with short stature caused by gain-of-function mutations in FGFR3 encoding the fibroblast growth factor receptor 3. We used the drug repositioning strategy to identify an FDA-approved drug that suppresses abnormally activated FGFR3 signaling in ACH. We found that meclozine, an anti-histamine drug that has long been used for motion sickness, facilitates chondrocyte proliferation and mitigates loss of extracellular matrix in FGF2-treated rat chondrosarcoma (RCS) cells. Meclozine also ameliorated abnormally suppressed proliferation of human chondrosarcoma (HCS-2/8) cells that were infected with lentivirus expressing constitutively active mutants of FGFR3-K650E causing thanatophoric dysplasia, FGFR3-K650M causing SADDAN, and FGFR3-G380R causing ACH. Similarly, meclozine alleviated abnormally suppressed differentiation of ATDC5 chondrogenic cells expressing FGFR3-K650E and -G380R in micromass culture. We also confirmed that meclozine alleviates FGF2-mediated longitudinal growth inhibition of embryonic tibia in bone explant culture. Interestingly, meclozine enhanced growth of embryonic tibia in explant culture even in the absence of FGF2 treatment. Analyses of intracellular FGFR3 signaling disclosed that meclozine downregulates phosphorylation of ERK but not of MEK in FGF2-treated RCS cells. Similarly, meclozine enhanced proliferation of RCS cells expressing constitutively active mutants of MEK and RAF but not of ERK, which suggests that meclozine downregulates the FGFR3 signaling by possibly attenuating ERK phosphorylation. We used the C-natriuretic peptide (CNP) as a potent inhibitor of the FGFR3 signaling throughout our experiments, and found that meclozine was as efficient as CNP in attenuating the abnormal FGFR3 signaling. We propose that meclozine is a potential therapeutic agent for treating ACH and other FGFR3-related skeletal dysplasias. PMID:24324705

  11. Calcium signaling and cell proliferation.

    PubMed

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

    2015-11-01

    Cell proliferation is orchestrated through diverse proteins related to calcium (Ca(2+)) signaling inside the cell. Cellular Ca(2+) influx that occurs first by various mechanisms at the plasma membrane, is then followed by absorption of Ca(2+) ions by mitochondria and endoplasmic reticulum, and, finally, there is a connection of calcium stores to the nucleus. Experimental evidence indicates that the fluctuation of Ca(2+) from the endoplasmic reticulum provides a pivotal and physiological role for cell proliferation. Ca(2+) depletion in the endoplasmatic reticulum triggers Ca(2+) influx across the plasma membrane in an phenomenon called store-operated calcium entries (SOCEs). SOCE is activated through a complex interplay between a Ca(2+) sensor, denominated STIM, localized in the endoplasmic reticulum and a Ca(2+) channel at the cell membrane, denominated Orai. The interplay between STIM and Orai proteins with cell membrane receptors and their role in cell proliferation is discussed in this review. PMID:26275497

  12. 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.

  13. 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.

  14. 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.

  15. Laminin 5 regulates polycystic kidney cell proliferation and cyst formation.

    PubMed

    Joly, Dominique; Berissi, Sophie; Bertrand, Amélie; Strehl, Laetitia; Patey, Natacha; Knebelmann, Bertrand

    2006-09-29

    Renal cyst formation is the hallmark of autosomal dominant polycystic kidney disease (ADPKD). ADPKD cyst-lining cells have an increased proliferation rate and are surrounded by an abnormal extracellular matrix (ECM). We have previously shown that Laminin 5 (Ln-5, a alpha(3)beta(3)gamma(2) trimer) is aberrantly expressed in the pericystic ECM of ADPKD kidneys. We report that ADPKD cells in primary cultures produce and secrete Ln-5 that is incorporated to the pericystic ECM in an in vitro model of cystogenesis. In monolayers, purified Ln-5 induces ERK activation and proliferation of ADPKD cells, whereas upon epidermal growth factor stimulation blocking endogenously produced Ln-5 with anti-gamma(2) chain antibody reduces the sustained ERK activation and inhibits proliferation. In three-dimensional gel culture, addition of purified Ln-5 stimulates cell proliferation and cyst formation, whereas blocking endogenous Ln-5 strongly inhibits cyst formation. Ligation of alpha(6)beta(4) integrin, a major Ln-5 receptor aberrantly expressed by ADPKD cells, induces beta(4) integrin phosphorylation, ERK activation, cell proliferation, and cyst formation. These findings indicate that Ln-5 is an important regulator of ADPKD cell proliferation and cystogenesis and suggest that Ln-5 gamma(2) chain and Ln-5-alpha(6)beta(4) integrin interaction both contribute to these phenotypic changes. PMID:16870608

  16. Hypoxia affects in vitro proliferation and differentiation of mouse corneal epithelial progenitor cell.

    PubMed

    Dong, Nuo; Qin, Wenjuan; Xue, Yuhua; Li, Cheng; Liu, Zuguo

    2013-08-01

    This study was to investigate the proliferation and differentiation of mouse corneal epithelial progenitor cell in hypoxic airlift culture. Mouse corneal epithelial progenitor cell line progenitor cells were cultured under airlift with normoxic and hypoxic conditions for various durations up to 2 wk. Under normoxic conditions when exposed to air, the hyperproliferation and abnormal epidermal-like differentiation of mouse corneal epithelium was induced, whereas when exposed to air under hypoxic conditions, although we observed augmented proliferation, the abnormal differentiation was inhibited. The mechanism by which hypoxia prevents abnormal differentiation may involve downregulation of Wnt signaling pathways, which were inhibited in cells cultured with hypoxic airlift technique. In conclusion, hypoxia can prevent abnormal differentiation while enhancing the proliferation of corneal epithelial cells by blocking Wnt/β-catenin signaling pathway. PMID:23739874

  17. Silencing of ILK attenuates the abnormal proliferation and migration of human Tenon's capsule fibroblasts induced by TGF-β2

    PubMed Central

    Xing, Yao; Cui, Lijun; Kang, Qianyan

    2016-01-01

    The cytokine, transforming growth factor-β (TGF-β), plays a key role in wound healing and tissue repair. Integrin-linked kinase (ILK) is a downstream factor of the TGF-β signaling pathway. Research on ILK has mainly focused on its role in the invasion and metastasis of cancer cells. However, little has been reported on the effects of ILK in human Tenon's capsule fibroblasts (HTFs). In this study, we investigated the role of ILK in the proliferation and migration of HTFs exposed to TGF-β2. A lentiviral vector targeting ILK was screened from three candidates and the experimental result indicated that RNA interference can be used to inhibit ILK expression at both the mRNA and protein level. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to assess ILK mRNA expression. Cell proliferation was quantified by MTT assay and cell cycle progression was detected by flow cytometric analysis. Migration was measured by wound healing assay. It was observed that the silencing of ILK suppressed the TGF-β2-induced proliferation of HTFs and led to G1 phase cell cycle arrest and the significant downregulation of cyclin D1 expression. The migration ability of the HTFs decreased following the silencing of ILK, while the downregulation of α-smooth muscle actin expression and the upregulation of E-cadherin expression were observed. The findings of our study indicate that the silencing of ILK attenuates the abnormal proliferation and migration of HTFs induced by TGF-β2, which reveals the therapeutic potential of ILK inhibition in the prevention of scarring following glaucoma filtration surgery. PMID:27315599

  18. Silencing of ILK attenuates the abnormal proliferation and migration of human Tenon's capsule fibroblasts induced by TGF-β2.

    PubMed

    Xing, Yao; Cui, Lijun; Kang, Qianyan

    2016-08-01

    The cytokine, transforming growth factor-β (TGF‑β), plays a key role in wound healing and tissue repair. Integrin‑linked kinase (ILK) is a downstream factor of the TGF-β signaling pathway. Research on ILK has mainly focused on its role in the invasion and metastasis of cancer cells. However, little has been reported on the effects of ILK in human Tenon's capsule fibroblasts (HTFs). In this study, we investigated the role of ILK in the proliferation and migration of HTFs exposed to TGF-β2. A lentiviral vector targeting ILK was screened from three candidates and the experimental result indicated that RNA interference can be used to inhibit ILK expression at both the mRNA and protein level. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to assess ILK mRNA expression. Cell proliferation was quantified by MTT assay and cell cycle progression was detected by flow cytometric analysis. Migration was measured by wound healing assay. It was observed that the silencing of ILK suppressed the TGF-β2-induced proliferation of HTFs and led to G1 phase cell cycle arrest and the significant downregulation of cyclin D1 expression. The migration ability of the HTFs decreased following the silencing of ILK, while the downregulation of α-smooth muscle actin expression and the upregulation of E-cadherin expression were observed. The findings of our study indicate that the silencing of ILK attenuates the abnormal proliferation and migration of HTFs induced by TGF-β2, which reveals the therapeutic potential of ILK inhibition in the prevention of scarring following glaucoma filtration surgery. PMID:27315599

  19. Piperine Congeners as Inhibitors of Vascular Smooth Muscle Cell Proliferation.

    PubMed

    Mair, Christina E; Liu, Rongxia; Atanasov, Atanas G; Wimmer, Laurin; Nemetz-Fiedler, Daniel; Sider, Nadine; Heiss, Elke H; Mihovilovic, Marko D; Dirsch, Verena M; Rollinger, Judith M

    2015-08-01

    Successful vascular healing after percutaneous coronary interventions is related to the inhibition of abnormal vascular smooth muscle cell proliferation and efficient re-endothelialization. In the search for vascular smooth muscle cell anti-proliferative agents from natural sources we identified piperine (1), the main pungent constituent of the fruits from Piper nigrum (black pepper). Piperine inhibited vascular smooth muscle cell proliferation with an IC50 of 21.6 µM, as quantified by a resazurin conversion assay. Investigations of ten piperamides isolated from black pepper fruits and 15 synthesized piperine derivatives resulted in the identification of three potent vascular smooth muscle cell proliferation inhibitors: the natural alkaloid pipertipine (4), and the two synthetic derivatives (2E,4E)-N,N-dibutyl-5-(3,5-dimethoxyphenyl)penta-2,4-dienamide (14) and (E)-N,N-dibutyl-3-(naphtho[2,3-d][1,3]dioxol-5-yl)acrylamide (20). They showed IC50 values of 3.38, 6.00, and 7.85 µM, respectively. Furthermore, the synthetic compound (2E,4E)-5-(4-fluorophenyl)-1-(piperidin-1-yl)penta-2,4-dien-1-one (12) was found to be cell type selective, by inhibiting vascular smooth muscle cell proliferation with an IC50 of 11.8 µM without influencing the growth of human endothelial cells. PMID:26132851

  20. Abnormally high expression of proteasomes in human leukemic cells.

    PubMed Central

    Kumatori, A; Tanaka, K; Inamura, N; Sone, S; Ogura, T; Matsumoto, T; Tachikawa, T; Shin, S; Ichihara, A

    1990-01-01

    Proteasomes are eukaryotic ring-shaped or cylindrical particles with multicatalytic protease activities. To clarify the involvement of proteasomes in tumorigenesis of human blood cells, we compared their expression in human hematopoietic malignant tumor cells with that in normal peripheral blood mononuclear cells. Immunohistochemical staining showed considerably increased concentrations of proteasomes in leukemic cells from the bone marrow of patients with various types of leukemia and the predominant localization of these proteasomes in the nuclei. Moreover, enzyme immunoassay and Northern blot analysis indicated that the concentrations of proteasomes and their mRNA levels were consistently much higher in a variety of malignant human hematopoietic cell lines than in resting peripheral lymphocytes and monocytes from healthy adults. Proteasome expression was also greatly increased in normal blood mononuclear cells during blastogenic transformation induced by phytohemagglutinin; their expression increased in parallel with induction of DNA synthesis and returned to the basal level with progress of the cell cycle. Thus, abnormally high expression of proteasomes may play an important role in transformation and proliferation of blood cells and in specific functions of hematopoietic tumor cells. Images PMID:2205851

  1. Abnormal proliferation and aging of cultured fibroblasts from pigs with subcutaneous fibrosis induced by gamma irradiation

    SciTech Connect

    Martin, M.; Remy, J.; Daburon, F. )

    1989-10-01

    In vivo, fibrotic disorders, which may be due either to injury or disease, are characterized by overproliferation of fibroblasts and overproduction of connective tissue. In vitro, however, most of the fibrotic cell lines studied exhibited no differences in growth potential compared with control cell lines derived from normal skin. In the present study, we investigated the in vitro behavior of fibroblasts derived from pigs with subcutaneous fibrosis induced by gamma irradiation. The cells were isolated from the scar tissue six to 20 months after irradiation. In primary cultures, the cells derived from the fibrotic lesions exhibited greater attachment efficiency and faster proliferation than those of the cells derived from the normal skin of the same animal. In long-term cultures, the differences between normal and fibrotic cells were still greater: the normal skin cells underwent 17 population doublings and then died, whereas the fibrotic cells exhibited a prolonged life span, and were still actively proliferating after 80 population doublings. Cell morphology and the number of chromosomes were modified throughout subcultures. These results imply that in the scar tissue active fibrotic cell proliferation continued for years after irradiation and that this activation was expressed in vitro. Therefore, in this pig fibrosis model, the data acquired in the present in vitro studies closely resemble that obtained from earlier in vivo observations.

  2. 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.

  3. Germ Cells Need Folate to Proliferate.

    PubMed

    Walker, Amy K

    2016-07-11

    In this issue of Developmental Cell, Chaudhari and colleagues (2016) use a novel method to create an in vitro proliferative cell line from tumorous C. elegans germ cells, and in the process discover that bacterial folates act as signals for proliferation, independent of their roles as vitamins. PMID:27404353

  4. 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.

  5. Cell proliferation is reduced in the hippocampus in schizophrenia

    PubMed Central

    Allen, Katherine M; Fung, Samantha J; Shannon Weickert, Cynthia

    2015-01-01

    Objective: The molecular and cellular basis of structural and functional abnormalities of the hippocampus found in schizophrenia is currently unclear. Postnatal neurogenesis contributes to hippocampal function in animal models and is correlated with hippocampal volume in primates. Reduced hippocampal cell proliferation has been previously reported in schizophrenia, which may contribute to hippocampal dysfunction. Method: We measured the cell proliferation marker, Ki67, in post-mortem hippocampal tissue from patients with schizophrenia (n = 10) and matched controls (n = 16). Ki67-labelled cells were counted within the dentate gyrus and hilus on sections taken from the anterior hippocampus. Results: We replicated the finding of a significant reduction in Ki67+ cells/mm2 in schizophrenia cases compared to controls (t24 = 2.1, p = 0.023). In our relatively small sample, we did not find a relationship between Ki67+ cells and age overall, or between Ki67 + cells and duration of illness or antipsychotic treatment in people with schizophrenia. Conclusion: Our results confirm that reduced hippocampal cell proliferation may be present in schizophrenia. Restoring hippocampal neurogenesis may be a potential therapeutic target for the treatment of hippocampal dysfunction in schizophrenia. PMID:26113745

  6. Proliferating pancreatic beta-cells upregulate ALDH.

    PubMed

    Liu, Yinglan; Jiang, Xiaoxin; Zeng, Yong; Zhou, Hui; Yang, Jing; Cao, Renxian

    2014-12-01

    High levels of aldehyde dehydrogenase (ALDH) activity have been regarded as a specific feature of progenitor cells and stem cells. Hence, as an indicator of ALDH activity, aldefluor fluorescence has been widely used for the identification and isolation of stem and progenitor cells. ALDH activity was recently detected in embryonic mouse pancreas, and specifically and exclusively in adult centroacinar and terminal duct cells, suggesting that these duct cells may harbor cells of endocrine and exocrine differentiation potential in the adult pancreas. Here, we report the presence of aldefluor+ beta-cells in a beta-cell proliferation model, partial pancreatectomy. The aldefluor+ beta-cells are essentially all positive for Ki-67 and expressed high levels of cell-cycle activators such as CyclinD1, CyclinD2, and CDK4, suggesting that they are mitotic cells. Our data thus reveal a potential change in ALDH activity of proliferating beta-cells, which provides a novel method for the isolation and analysis of proliferating beta-cells. Moreover, our data also suggest that aldefluor lineage-tracing is not a proper method for analyzing progenitor or stem activity in the adult pancreas. PMID:25028343

  7. 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.

  8. TWEAK induces liver progenitor cell proliferation.

    PubMed

    Jakubowski, Aniela; Ambrose, Christine; Parr, Michael; Lincecum, John M; Wang, Monica Z; Zheng, Timothy S; Browning, Beth; Michaelson, Jennifer S; Baetscher, Manfred; Baestcher, Manfred; Wang, Bruce; Bissell, D Montgomery; Burkly, Linda C

    2005-09-01

    Progenitor ("oval") cell expansion accompanies many forms of liver injury, including alcohol toxicity and submassive parenchymal necrosis as well as experimental injury models featuring blocked hepatocyte replication. Oval cells can potentially become either hepatocytes or biliary epithelial cells and may be critical to liver regeneration, particularly when hepatocyte replication is impaired. The regulation of oval cell proliferation is incompletely understood. Herein we present evidence that a TNF family member called TWEAK (TNF-like weak inducer of apoptosis) stimulates oval cell proliferation in mouse liver through its receptor Fn14. TWEAK has no effect on mature hepatocytes and thus appears to be selective for oval cells. Transgenic mice overexpressing TWEAK in hepatocytes exhibit periportal oval cell hyperplasia. A similar phenotype was obtained in adult wild-type mice, but not Fn14-null mice, by administering TWEAK-expressing adenovirus. Oval cell expansion induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) was significantly reduced in Fn14-null mice as well as in adult wild-type mice with a blocking anti-TWEAK mAb. Importantly, TWEAK stimulated the proliferation of an oval cell culture model. Finally, we show increased Fn14 expression in chronic hepatitis C and other human liver diseases relative to its expression in normal liver, which suggests a role for the TWEAK/Fn14 pathway in human liver injury. We conclude that TWEAK has a selective mitogenic effect for liver oval cells that distinguishes it from other previously described growth factors. PMID:16110324

  9. Spatial constraints control cell proliferation in tissues

    PubMed Central

    Streichan, Sebastian J.; Hoerner, Christian R.; Schneidt, Tatjana; Holzer, Daniela; Hufnagel, Lars

    2014-01-01

    Control of cell proliferation is a fundamental aspect of tissue formation in development and regeneration. Cells experience various spatial and mechanical constraints depending on their environmental context in the body, but we do not fully understand if and how such constraints influence cell cycle progression and thereby proliferation patterns in tissues. Here, we study the impact of mechanical manipulations on the cell cycle of individual cells within a mammalian model epithelium. By monitoring the response to experimentally applied forces, we find a checkpoint at the G1–S boundary that, in response to spatial constraints, controls cell cycle progression. This checkpoint prevents cells from entering S phase if the available space remains below a characteristic threshold because of crowding. Stretching the tissue results in fast cell cycle reactivation, whereas compression rapidly leads to cell cycle arrest. Our kinetic analysis of this response shows that cells have no memory of past constraints and allows us to formulate a biophysical model that predicts tissue growth in response to changes in spatial constraints in the environment. This characteristic biomechanical cell cycle response likely serves as a fundamental control mechanism to maintain tissue integrity and to ensure control of tissue growth during development and regeneration. PMID:24706777

  10. 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

  11. BCOR regulates myeloid cell proliferation and differentiation.

    PubMed

    Cao, Q; Gearhart, M D; Gery, S; Shojaee, S; Yang, H; Sun, H; Lin, D-C; Bai, J-W; Mead, M; Zhao, Z; Chen, Q; Chien, W-W; Alkan, S; Alpermann, T; Haferlach, T; Müschen, M; Bardwell, V J; Koeffler, H P

    2016-05-01

    BCOR is a component of a variant Polycomb group repressive complex 1 (PRC1). Recently, we and others reported recurrent somatic BCOR loss-of-function mutations in myelodysplastic syndrome and acute myelogenous leukemia (AML). However, the role of BCOR in normal hematopoiesis is largely unknown. Here, we explored the function of BCOR in myeloid cells using myeloid murine models with Bcor conditional loss-of-function or overexpression alleles. Bcor mutant bone marrow cells showed significantly higher proliferation and differentiation rates with upregulated expression of Hox genes. Mutation of Bcor reduced protein levels of RING1B, an H2A ubiquitin ligase subunit of PRC1 family complexes and reduced H2AK119ub upstream of upregulated HoxA genes. Global RNA expression profiling in murine cells and AML patient samples with BCOR loss-of-function mutation suggested that loss of BCOR expression is associated with enhanced cell proliferation and myeloid differentiation. Our results strongly suggest that BCOR plays an indispensable role in hematopoiesis by inhibiting myeloid cell proliferation and differentiation and offer a mechanistic explanation for how BCOR regulates gene expression such as Hox genes. PMID:26847029

  12. MicroRNA-141 inhibits vascular smooth muscle cell proliferation through targeting PAPP-A

    PubMed Central

    Zhang, Yudong; Chen, Bainan; Ming, Liu; Qin, Hongsong; Zheng, Liu; Yue, Zhang; Cheng, Zhixin; Wang, Yannan; Zhang, Dawei; Liu, Chunmei; Bin, Wang; Hao, Qingzhi; Song, Fuchen; Ji, Bo

    2015-01-01

    It is well known that ox-LDL plays key roles in the development of atherosclerosis, partly by inducing vascular smooth muscle cells (VSMCs) proliferation. Recent findings have revealed that microRNAs, a class of small noncoding RNAs, could regulate cell proliferation in many physiological and pathological conditions. However, the role and function of miRNAs on ox-LDL induced VSMC proliferation are not fully elucidated. In this study, we showed that ox-LDL could suppress miR-141 expression and inhibition of miR-141 could promote VSMCs proliferation. Moreover, we found that PAPPA was the direct target gene of miR-141. Overexpression of PAPPA impaired the miR-141-induced inhibition of proliferation in the VSMCs. Taken together; miR-141 may play important roles in ox-LDL-induced abnormal proliferation of the VSMC. PMID:26823756

  13. 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

  14. 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

  15. 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.

  16. Visualizing how cancer chromosome abnormalities form in living cells

    Cancer.gov

    For the first time, scientists have directly observed events that lead to the formation of a chromosome abnormality that is often found in cancer cells. The abnormality, called a translocation, occurs when part of a chromosome breaks off and becomes attac

  17. Cell cycle regulators and their abnormalities in breast cancer.

    PubMed Central

    Fernández, P L; Jares, P; Rey, M J; Campo, E; Cardesa, A

    1998-01-01

    One of the main properties of cancer cells is their increased and deregulated proliferative activity. It is now well known that abnormalities in many positive and negative modulators of the cell cycle are frequent in many cancer types, including breast carcinomas. Abnormalities such as defective function of the retinoblastoma gene and cyclin-dependent kinase inhibitors (for example, p16, p21, and p27), as well as upregulation of cyclins, are often seen in breast tumours. These abnormalities are sometimes coincidental, and newly described interplays between them suggest the existence of a complex regulatory web in the cell cycle. PMID:10193510

  18. The effect of abnormal cell proportion on specimen classifier performance

    NASA Technical Reports Server (NTRS)

    Castleman, K. R.; White, B. S.

    1981-01-01

    An analysis is presented of the results obtained from a cell classifier which is confronted with an abnormal/normal cell ratio which is different from the ratio assumed in the calibration of the classifier. False negative and false positive error rates are determined in advance for classifier operation, along with the necessary sample size in order to validate the predicted distributions. Changes are demonstrated to happen only regarding the false negative rate, where reductions in the abnormal cell rate below the expected rates would cause totally unreliable data. Substantial overproduction of abnormal cells would be quickly noticeable, while production rates beyond, but close to, the expected rates would only require more extensive sampling. Classifier systems for 10% proportions of abnormal cells are concluded to be possible, but difficulties are present with much lower rates

  19. Carbendazim Inhibits Cancer Cell Proliferation by Suppressing Microtubule Dynamics

    PubMed Central

    Yenjerla, Mythili; Cox, Corey; Wilson, Leslie; Jordan, Mary Ann

    2009-01-01

    Carbendazim (methyl 2-benzimidazolecarbamate) is widely used as a systemic fungicide in human food production and appears to act on fungal tubulin. However, it also inhibits proliferation of human cancer cells, including drug- and multidrug-resistant and p53-deficient cell lines. Because of its promising preclinical anti-tumor activity, it has undergone phase I clinical trials and is under further clinical development. Although it weakly inhibits polymerization of brain microtubules and induces G2/M arrest in tumor cells, its mechanism of action in human cells has not been fully elucidated. We examined its mechanism of action in MCF7 human breast cancer cells and found that it inhibits proliferation (IC50, 10 μM) and half-maximally arrests mitosis at a similar concentration (8 μM), in concert with suppression of microtubule dynamic instability without appreciable microtubule depolymerization. It induces mitotic spindle abnormalities and reduces the metaphase intercentromere distance of sister chromatids, indicating reduction of tension on kinetochores, thus leading to metaphase arrest. With microtubules assembled in vitro from pure tubulin, carbendazim also suppresses dynamic instability, reducing the dynamicity by 50% at 10 μM, with only minimal (21%) reduction of polymer mass. Carbendazim binds to mammalian tubulin (Kd, 42.8 ± 4.0 μM). Unlike some benzimidazoles that bind to the colchicine site in tubulin, carbendazim neither competes with colchicine nor competes with vinblastine for binding to brain tubulin. Thus, carbendazim binds to an as yet unidentified site in tubulin and inhibits tumor cell proliferation by suppressing the growing and shortening phases of microtubule dynamic instability, thus inducing mitotic arrest. PMID:19001156

  20. Abnormal Schwann cell/axon interactions in the Trembler-J mouse

    PubMed Central

    ROBERTSON, A. M.; KING, R. H. M.; MUDDLE, J. R.; THOMAS, P. K.

    1997-01-01

    The Trembler-J (TrJ) mouse has a point mutation in the gene coding for peripheral myelin protein 22 (PMP22). Disturbances in PMP22 are associated with abnormal myelination in a range of inherited peripheral neuropathies both in mice and humans. PMP22 is produced mainly by Schwann cells in the peripheral nervous system where it is localised to compact myelin. The function of PMP22 is unclear but its low abundance (∼5% of total myelin protein) means that it is unlikely to play a structural role. Its inclusion in a recently discovered family of proteins suggests a function in cell proliferation/differentiation and possibly in adhesion. Nerves from TrJ and the allelic Trembler (Tr) mouse are characterised by abnormally thin myelin for the size of the axon and an increased number of Schwann cells. We report ultrastructural evidence of abnormal Schwann cell-axon interactions. Schwann cell nuclei have been found adjacent to the nodes of Ranvier whereas in normal animals they are located near the centre of the internodes. In some fibres the terminal myelin loops faced outwards into the extracellular space instead of turning inwards and terminating on the axon. In severely affected nerves many axons were only partially surrounded by Schwann cell cytoplasm. All these features suggest a failure of Schwann cell–axon recognition or interaction. In addition to abnormalities related to abnormal myelination there was significant axonal loss in the dorsal roots. PMID:9147228

  1. 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

  2. [Enhanced control of proliferation in telomerized cells].

    PubMed

    Egorov, E E; Moldaver, M V; Vishniakova, Kh S; Terekhov, S M; Dashinimaev, E B; Cheglakov, I B; Toropygin, I Iu; Iarygin, K N; Chumakov, P M; Korochkin, L I; Antonova, G A; Rybalkina, E Iu; Saburina, I N; Burnaevskiĭ, N S; Zelenin, A V

    2007-01-01

    Clones of telomerized fibroblasts of adult human skin have earlier been obtained. It was shown that despite their fast growth in mass cultures, these cells poorly form colonies. Conditioned medium, antioxidants, and reduced partial oxygen pressure enhanced their colony formation, but not to the level characteristic of the initial cells. The conditioned medium of telomerized cells enhanced colony formation to a much greater extent than that of the initial cells. A study of proteome of the telomerized fibroblasts has revealed changes in the activities of tens of genes. A general trend consists in weakening and increased lability of the cytoskeleton and in activation of the mechanisms controlling protein degradation. However, these changes are not very pronounced. During the formation of immortal telomerized cells, selection takes place, which appears to determine changes in the expression of some genes. It was proposed that a decrease in the capacity of telomerized cells for colony formation is due to increased requirements of these cells to cell-cell contacts. The rate of cell growth reached that characteristic of mass cultures only in the largest colonies. In this respect, the telomerized fibroblasts resembled stem cells: they are capable of self-maintenance, but "escape" to differentiation in the absence of the corresponding microenvironment (niche), which is represented by other fibroblasts. Non-dividing cells in the test of colony formation should be regarded as differentiated cells, since they have no features of degradation, preserve their viability, actively move, grow, phagocytized debris, etc. It was also shown that telomerization did not prevent differentiation of myoblasts and human neural stem cells. Thus, the results obtained suggest the existence of normal mechanisms underlying the regulation of proliferation in the telomerized cells, which opens possibilities of their use in cell therapy, especially in the case of autotransplantation to senior people

  3. Collagen coated tantalum substrate for cell proliferation.

    PubMed

    Li, Yinli; Zhang, Shuai; Guo, Lijun; Dong, Mingdong; Liu, Bo; Mamdouh, Wael

    2012-06-15

    The extracellular matrix (ECM) plays a key role in cell culture in various physiological and pathological processes in the field of tissue engineering. Recently, the type I collagen ECM has been widely utilized in vitro model systems for the attachment of many different cell lines since it has multi-functions in human tissues. For example it accounts for 6% of the weight of strong, tendinous muscles. In this paper, we reported a new material by coating tantalum (Ta), one highly biocompatible metal, with type I collagen fibrils. The morphology of the new material was studied by high resolution atomic force microscope. It was shown that the adhesion force between type I collagen fibrils network and Ta was strong enough to overcome surface defects. A possible way to explain the phenomenon is that the longitudinal periodicity of collagen fibrils matches the grain size of the Ta domains, which results in increase of the physical adsorption contact area, thereby inducing the dramatic adhesion enhancement between collagen fibrils and Ta. The obtained material was then employed as a template for cell proliferation. Although the surface of this template is more hydrophobic by comparison with the bare Ta surface, the cells on this material were successfully incubated, indicating that the collagen coated Ta might be used as the buffer layer for proliferating cells in hydrophobic biomaterials. PMID:22494669

  4. Selective cell proliferation can be controlled with CPC particle coatings

    PubMed Central

    Szivek, J.A.; Margolis, D.S.; Schnepp, A.B.; Grana, W.A.; Williams, S.K.

    2008-01-01

    To develop implantable, engineered, cartilage constructs supported by a scaffold, techniques to encourage rapid tissue growth into, and on the scaffold are essential. Preliminary studies indicated that human endothelial cells proliferated at different rates on different calcium phosphate ceramic (CPC) particles. Judicious selection of particles may encourage specific cell proliferation, leading to an ordered growth of tissues for angiogenesis, osteogenesis, and chondrogenesis. The goal of this study was to identify CPC surfaces that encourage bone and vascular cell growth, and other surfaces that support chondrocyte growth while inhibiting proliferation of vascular cells. Differences in bone and vascular cell proliferation were observed when using epoxy without embedded CPCs to encourage bone cells, and when three CPCs were tested, which encouraged vascular cell proliferation. One of these (CPC 7) also substantially depressed cartilage cell proliferation. Only one small-diameter crystalline CPC (CPC 2) supported rapid chondrocyte proliferation, and maintained the cartilage cell phenotype. PMID:17252549

  5. Leptin promotes cell proliferation and survival of trophoblastic cells.

    PubMed

    Magariños, María Paula; Sánchez-Margalet, Víctor; Kotler, Mónica; Calvo, Juan Carlos; Varone, Cecilia L

    2007-02-01

    Leptin, the 16-kDa protein product of the obese gene, was originally considered as an adipocyte-derived signaling molecule for the central control of metabolism. However, leptin has been suggested to be involved in other functions during pregnancy, particularly in placenta. In the present work, we studied a possible effect of leptin on trophoblastic cell proliferation, survival, and apoptosis. Recombinant human leptin added to JEG-3 and BeWo choriocarcinoma cell lines showed a stimulatory effect on cell proliferation up to 3 and 2.4 times, respectively, measured by (3)H-thymidine incorporation and cell counting. These effects were time and dose dependent. Maximal effect was achieved at 250 ng leptin/ml for JEG-3 cells and 50 ng leptin/ml for BeWo cells. Moreover, by inhibiting endogenous leptin expression with 2 microM of an antisense oligonucleotide (AS), cell proliferation was diminished. We analyzed cell population distribution during the different stages of cell cycle by fluorescence-activated cell sorting, and we found that leptin treatment displaced the cells towards a G2/M phase. We also found that leptin upregulated cyclin D1 expression, one of the key cell cycle-signaling proteins. Since proliferation and death processes are intimately related, the effect of leptin on cell apoptosis was investigated. Treatment with 2 microM leptin AS increased the number of apoptotic cells 60 times, as assessed by annexin V-fluorescein isothiocyanate/propidium iodide staining, and the caspase-3 activity was increased more than 2 fold. This effect was prevented by the addition of 100 ng leptin/ml. In conclusion, we provide evidence that suggests that leptin is a trophic and mitogenic factor for trophoblastic cells by virtue of its inhibiting apoptosis and promoting proliferation. PMID:17021346

  6. Liver epithelial cells inhibit proliferation and invasiveness of hepatoma cells.

    PubMed

    Jeng, Kuo-Shyang; Jeng, Chi-Juei; Jeng, Wen-Juei; Sheen, I-Shyan; Li, Shih-Yun; Hung, Zih-Hang; Hsiau, Hsin-I; Yu, Ming-Che; Chang, Chiung-Fang

    2016-03-01

    Hepatocellular carcinoma (HCC) is a worldwide malignancy with poor prognosis. Liver progenitors or stem cells could be a potential therapy for HCC treatment since they migrate toward tumors. Rat liver epithelial (RLE) cells have both progenitor and stem cell-like properties. Therefore, our study elucidated the therapeutic effect of RLE cells in rat hepatoma cells. RLE cells were isolated from 10-day old rats and characterized for stem cell marker expression. RLE cells and rat hepatoma cells (H4-IIE-C3 cells) were co-cultured and divided into four groups with different ratios of RLE and hepatoma cells. Group A had only rat hepatoma cells as a control group. The ratios of rat hepatoma and RLE cells in group B, C and D were 5:1, 1:1 and 1:5, respectively. Effective inhibition of cell proliferation and migration was found in group D when compared to group A. There was a significant decrease in Bcl2 expression and increase in late apoptosis of rat hepatoma cells when adding more RLE cells. RLE cells reduced cell proliferation and migration of rat hepatoma cells. These results suggested that RLE cells could be used as a potential cell therapy. PMID:26647726

  7. Post microtextures accelerate cell proliferation and osteogenesis.

    PubMed

    Kim, Eun Jung; Boehm, Cynthia A; Mata, Alvaro; Fleischman, Aaron J; Muschler, George F; Roy, Shuvo

    2010-01-01

    The influence of surface microtexture on osteogenesis was investigated in vitro by examining the proliferation and differentiation characteristics of a class of adult stem cells and their progeny, collectively known as connective tissue progenitor cells (CTPs). Human bone marrow-derived CTPs were cultured for up to 60 days on smooth polydimethylsiloxane (PDMS) surfaces and on PDMS with post microtextures that were 10 microm in diameter and 6 microm in height, with 10 microm separation. DNA quantification revealed that the numbers of CTPs initially attached to both substrates were similar. However, cells on microtextured PDMS transitioned from lag phase after 4 days of culture, in contrast to 6 days for cells on smooth surfaces. By day 9 cells on the smooth surfaces exhibited arbitrary flattened shapes and migrated without any preferred orientation. In contrast, cells on the microtextured PDMS grew along the array of posts in an orthogonal manner. By days 30 and 60 cells grew and covered all surfaces with extracellular matrix. Western blot analysis revealed that the expression of integrin alpha5 was greater on the microtextured PDMS compared with smooth surfaces. Real time reverse transcription-polymerase chain reaction revealed that gene expression of alkaline phosphatase had decreased by days 30 and 60, compared with that on day 9, for both substrates. Gene expression of collagen I and osteocalcin was consistently greater on post microtextures relative to smooth surfaces at all time points. PMID:19539062

  8. Post microtextures accelerate cell proliferation and osteogenesis

    PubMed Central

    Kim, Eun Jung; Boehm, Cynthia A.; Mata, Alvaro; Fleischman, Aaron J.; Muschler, George F.; Roy, Shuvo

    2013-01-01

    The influence of surface microtexture on osteogenesis was investigated in vitro by examining the proliferation and differentiation characteristics of a class of adult stem cells and their progeny, collectively known as connective tissue progenitor cells (CTPs). Human bone marrow-derived CTPs were cultured for up to 60 days on smooth polydimethylsiloxane (PDMS) surfaces and on PDMS with post microtextures that were 10 µm in diameter and 6 µm in height, with 10 µm separation. DNA quantification revealed that the numbers of CTPs initially attached to both substrates were similar. However, cells on microtextured PDMS transitioned from lag phase after 4 days of culture, in contrast to 6 days for cells on smooth surfaces. By day 9 cells on the smooth surfaces exhibited arbitrary flattened shapes and migrated without any preferred orientation. In contrast, cells on the microtextured PDMS grew along the array of posts in an orthogonal manner. By days 30 and 60 cells grew and covered all surfaces with extracellular matrix. Western blot analysis revealed that the expression of integrin α5 was greater on the microtextured PDMS compared with smooth surfaces. Real time reverse transcription-polymerase chain reaction revealed that gene expression of alkaline phosphatase had decreased by days 30 and 60, compared with that on day 9, for both substrates. Gene expression of collagen I and osteocalcin was consistently greater on post microtextures relative to smooth surfaces at all time points. PMID:19539062

  9. Quantitative analysis of in vivo cell proliferation.

    PubMed

    Cameron, Heather A

    2006-11-01

    Injection and immunohistochemical detection of 5-bromo-2'-deoxyuridine (BrdU) has become the standard method for studying the birth and survival of neurons, glia, and other cell types in the nervous system. BrdU, a thymidine analog, becomes stably incorporated into DNA during the S-phase of mitosis. Because DNA containing BrdU can be specifically recognized by antibodies, this method allows dividing cells to be marked at any given time and then identified at time points from a few minutes to several years later. BrdU immunohistochemistry is suitable for cell counting to examine the regulation of cell proliferation and cell fate. It can be combined with labeling by other antibodies, allowing confocal analysis of cell phenotype or expression of other proteins. The potential for nonspecific labeling and toxicity are discussed. Although BrdU immunohistochemistry has almost completely replaced tritiated thymidine autoradiography for labeling dividing cells, this method and situations in which it is still useful are also described. PMID:18428635

  10. Mxi1 regulates cell proliferation through insulin-like growth factor binding protein-3

    SciTech Connect

    Ko, Je Yeong; Yoo, Kyung Hyun; Lee, Han-Woong; Park, Jong Hoon

    2011-11-11

    Highlights: Black-Right-Pointing-Pointer Mxi1 regulates cell proliferation. Black-Right-Pointing-Pointer Expression of IGFBP-3 is regulated by Mxi1. Black-Right-Pointing-Pointer Inactivation of Mxi1 reduces IGFBP-3 expression in vitro and in vivo. -- Abstract: Mxi1, a member of the Myc-Max-Mad network, is an antagonist of the c-Myc oncogene and is associated with excessive cell proliferation. Abnormal cell proliferation and tumorigenesis are observed in organs of Mxi1-/- mice. However, the Mxi1-reltaed mechanism of proliferation is unclear. The present study utilized microarray analysis using Mxi1 mouse embryonic fibroblasts (MEFs) to identify genes associated with cell proliferation. Among these genes, insulin-like growth factor binding protein-3 (IGFBP-3) was selected as a candidate gene for real-time PCR to ascertain whether IGFBP-3 expression is regulated by Mxi1. Expression of IGFBP-3 was decreased in Mxi1-/- MEFs and Mxi1-/- mice, and the gene was regulated by Mxi1 in Mxi1 MEFs. Furthermore, proliferation pathways related to IGFBP-3 were regulated in Mxi1-/- mice compared to Mxi1+/+ mice. To determine the effect of Mxi1 inactivation on the induction of cell proliferation, a proliferation assay is performed in both Mxi1 MEFs and Mxi1 mice. Cell viability was regulated by Mxi1 in Mxi1 MEFs and number of PCNA-positive cells was increased in Mxi1-/- mice compared to Mxi1+/+ mice. Moreover, the IGFBP-3 level was decreased in proliferation defect regions in Mxi1-/- mice. The results support the suggestion that inactivation of Mxi1 has a positive effect on cell proliferation by down-regulating IGFBP-3.

  11. Overexpression of AQP3 Modifies the Cell Cycle and the Proliferation Rate of Mammalian Cells in Culture.

    PubMed

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

    2015-01-01

    Abnormal AQP3 overexpression in tumor cells of different origins has been reported and a role for this enhanced AQP3 expression in cell proliferation and tumor processess has been indicated. To further understand the role AQP3 plays in cell proliferation we explore the effect that stable over expression of AQP3 produces over the proliferation rate and cell cycle of mammalian cells. The cell cycle was analyzed by flow cytometry with propidium iodide (PI) and the cell proliferation rate measured through cell counting and BrdU staining. Cells with overexpression of AQP3 (AQP3-o) showed higher proliferation rate and larger percentage of cells in phases S and G2/M, than wild type cells (wt). Evaluation of the cell response against arresting the cell cycle with Nocodazole showed that AQP3-o exhibited a less modified cell cycle pattern and lower Annexin V specific staining than wt, consistently with a higher resistance to apoptosis of AQP3-overexpressing cells. The cell volume and complexity were also larger in AQP3-o compared to wt cells. After transcriptomic analysis, RT-qPCR was performed to highlight key molecules implicated in cell proliferation which expression may be altered by overexpression of AQP3 and the comparative analysis between both type of cells showed significant changes in the expression of Zeb2, Jun, JunB, NF-kβ, Cxcl9, Cxcl10, TNF, and TNF receptors. We conclude that the role of AQP3 in cell proliferation seems to be connected to increments in the cell cycle turnover and changes in the expression levels of relevant genes for this process. Larger expression of AQP3 may confer to the cell a more tumor like phenotype and contributes to explain the presence of this protein in many different tumors. PMID:26367709

  12. Overexpression of AQP3 Modifies the Cell Cycle and the Proliferation Rate of Mammalian Cells in Culture

    PubMed Central

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

    2015-01-01

    Abnormal AQP3 overexpression in tumor cells of different origins has been reported and a role for this enhanced AQP3 expression in cell proliferation and tumor processess has been indicated. To further understand the role AQP3 plays in cell proliferation we explore the effect that stable over expression of AQP3 produces over the proliferation rate and cell cycle of mammalian cells. The cell cycle was analyzed by flow cytometry with propidium iodide (PI) and the cell proliferation rate measured through cell counting and BrdU staining. Cells with overexpression of AQP3 (AQP3-o) showed higher proliferation rate and larger percentage of cells in phases S and G2/M, than wild type cells (wt). Evaluation of the cell response against arresting the cell cycle with Nocodazole showed that AQP3-o exhibited a less modified cell cycle pattern and lower Annexin V specific staining than wt, consistently with a higher resistance to apoptosis of AQP3-overexpressing cells. The cell volume and complexity were also larger in AQP3-o compared to wt cells. After transcriptomic analysis, RT-qPCR was performed to highlight key molecules implicated in cell proliferation which expression may be altered by overexpression of AQP3 and the comparative analysis between both type of cells showed significant changes in the expression of Zeb2, Jun, JunB, NF-kβ, Cxcl9, Cxcl10, TNF, and TNF receptors. We conclude that the role of AQP3 in cell proliferation seems to be connected to increments in the cell cycle turnover and changes in the expression levels of relevant genes for this process. Larger expression of AQP3 may confer to the cell a more tumor like phenotype and contributes to explain the presence of this protein in many different tumors. PMID:26367709

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

    PubMed

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

    2013-11-12

    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

  14. Potassium channels in cell cycle and cell proliferation

    PubMed Central

    Urrego, Diana; Tomczak, Adam P.; Zahed, Farrah; Stühmer, Walter; Pardo, Luis A.

    2014-01-01

    Normal cell-cycle progression is a crucial task for every multicellular organism, as it determines body size and shape, tissue renewal and senescence, and is also crucial for reproduction. On the other hand, dysregulation of the cell-cycle progression leading to uncontrolled cell proliferation is the hallmark of cancer. Therefore, it is not surprising that it is a tightly regulated process, with multifaceted and very complex control mechanisms. It is now well established that one of those mechanisms relies on ion channels, and in many cases specifically on potassium channels. Here, we summarize the possible mechanisms underlying the importance of potassium channels in cell-cycle control and briefly review some of the identified channels that illustrate the multiple ways in which this group of proteins can influence cell proliferation and modulate cell-cycle progression. PMID:24493742

  15. Neural tube defects and impaired neural progenitor cell proliferation in Gbeta1-deficient mice.

    PubMed

    Okae, Hiroaki; Iwakura, Yoichiro

    2010-04-01

    Heterotrimeric G proteins are well known for their roles in signal transduction downstream of G protein-coupled receptors (GPCRs), and both Galpha subunits and tightly associated Gbetagamma subunits regulate downstream effector molecules. Compared to Galpha subunits, the physiological roles of individual Gbeta and Ggamma subunits are poorly understood. In this study, we generated mice deficient in the Gbeta1 gene and found that Gbeta1 is required for neural tube closure, neural progenitor cell proliferation, and neonatal development. About 40% Gbeta1(-/-) embryos developed neural tube defects (NTDs) and abnormal actin organization was observed in the basal side of neuroepithelium. In addition, Gbeta1(-/-) embryos without NTDs showed microencephaly and died within 2 days after birth. GPCR agonist-induced ERK phosphorylation, cell proliferation, and cell spreading, which were all found to be regulated by Galphai and Gbetagamma signaling, were abnormal in Gbeta1(-/-) neural progenitor cells. These data indicate that Gbeta1 is required for normal embryonic neurogenesis. PMID:20186915

  16. Deficiency of Cardiolipin Synthase Causes Abnormal Mitochondrial Function and Morphology in Germ Cells of Caenorhabditis elegans*

    PubMed Central

    Sakamoto, Taro; Inoue, Takao; Otomo, Yukae; Yokomori, Nagaharu; Ohno, Motoki; Arai, Hiroyuki; Nakagawa, Yasuhito

    2012-01-01

    Cardiolipin (CL) is a major membrane phospholipid specifically localized in mitochondria. At the cellular level, CL has been shown to have a role in mitochondrial energy production, mitochondrial membrane dynamics, and the triggering of apoptosis. However, the in vivo role of CL in multicellular organisms is largely unknown. In this study, by analyzing deletion mutants of a CL synthase gene (crls-1) in Caenorhabditis elegans, we demonstrated that CL depletion selectively caused abnormal mitochondrial function and morphology in germ cells but not in somatic cell types such as muscle cells. crls-1 mutants reached adulthood but were sterile with reduced germ cell proliferation and impaired oogenesis. In the gonad of crls-1 mutants, mitochondrial membrane potential was significantly decreased, and the structure of the mitochondrial cristae was disrupted. Contrary to the abnormalities in the gonad, somatic tissues in crls-1 mutants appeared normal with respect to cell proliferation, mitochondrial function, and mitochondrial morphology. Increased susceptibility to CL depletion in germ cells was also observed in mutants of phosphatidylglycerophosphate synthase, an enzyme responsible for producing phosphatidylglycerol, a precursor phospholipid of CL. We propose that the contribution of CL to mitochondrial function and morphology is different among the cell types in C. elegans. PMID:22174409

  17. Bile acids regulate intestinal cell proliferation by modulating EGFR and FXR signaling.

    PubMed

    Dossa, Avafia Y; Escobar, Oswaldo; Golden, Jamie; Frey, Mark R; Ford, Henri R; Gayer, Christopher P

    2016-01-15

    Bile acids (BAs) are synthesized in the liver and secreted into the intestine. In the lumen, enteric bacteria metabolize BAs from conjugated, primary forms into more toxic unconjugated, secondary metabolites. Secondary BAs can be injurious to the intestine and may contribute to disease. The epidermal growth factor receptor (EGFR) and the nuclear farnesoid X receptor (FXR) are known to interact with BAs. In this study we examined the effects of BAs on intestinal epithelial cell proliferation and investigated the possible roles for EGFR and FXR in these effects. We report that taurine-conjugated cholic acid (TCA) induced proliferation, while its unconjugated secondary counterpart deoxycholic acid (DCA) inhibited proliferation. TCA stimulated phosphorylation of Src, EGFR, and ERK 1/2. Pharmacological blockade of any of these pathways or genetic ablation of EGFR abrogated TCA-stimulated proliferation. Interestingly, Src or EGFR inhibitors eliminated TCA-induced phosphorylation of both molecules, suggesting that their activation is interdependent. In contrast to TCA, DCA exposure diminished EGFR phosphorylation, and pharmacological or siRNA blockade of FXR abolished DCA-induced inhibition of proliferation. Taken together, these results suggest that TCA induces intestinal cell proliferation via Src, EGFR, and ERK activation. In contrast, DCA inhibits proliferation via an FXR-dependent mechanism that may include downstream inactivation of the EGFR/Src/ERK pathway. Since elevated secondary BA levels are the result of specific bacterial modification, this may provide a mechanism through which an altered microbiota contributes to normal or abnormal intestinal epithelial cell proliferation. PMID:26608185

  18. [The effects of actovegin on cell proliferation of permanent lines].

    PubMed

    Gulevskiĭ, A K; Trifonova, A V; Lavrik, A A

    2008-01-01

    The influence of Actovegin on proliferation activity and mitotic regimen of cells of permanent lines PK-15-IEKVM and BHK-21 clone 13/04 was investigated. Addition of Actovegin into growth media containing bovine serums of different components and concentrations stimulates cell proliferation. Conclusion has been made that Actovegin can be used in cell culture biotechnology. PMID:18411759

  19. Proliferation of mutators in A cell population.

    PubMed Central

    Mao, E F; Lane, L; Lee, J; Miller, J H

    1997-01-01

    A Lac- strain of Escherichia coli that reverts by the addition of a G to a G-G-G-G-G-G sequence was used to study the proliferation of mutators in a bacterial culture. Selection for the Lac+ phenotype, which is greatly stimulated in mismatch repair-deficient strains, results in an increase in the percentage of mutators in the selected population from less than 1 per 100,000 cells to 1 per 200 cells. All the mutators detected were deficient in the mismatch repair system. Mutagenesis results in a similar increase in the percentage of mutators. Mutagenesis combined with a single selection can result in a population of more than 50% mutators when a sample of several thousand cells is grown out and selected. Mutagenesis combined with two or more successive selections can generate a population that is 100% mutator. These experiments are discussed in relation to ideas that an early step in carcinogenesis is the creation of a mutator phenotype. PMID:8990293

  20. Proliferating cell nuclear antigen in neutrophil fate.

    PubMed

    Witko-Sarsat, Véronique; Ohayon, Delphine

    2016-09-01

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

  1. Regulation of cell proliferation by hypoxia-inducible factors.

    PubMed

    Hubbi, Maimon E; Semenza, Gregg L

    2015-12-15

    Hypoxia is a physiological cue that impacts diverse physiological processes, including energy metabolism, autophagy, cell motility, angiogenesis, and erythropoiesis. One of the key cell-autonomous effects of hypoxia is as a modulator of cell proliferation. For most cell types, hypoxia induces decreased cell proliferation, since an increased number of cells, with a consequent increase in O2 demand, would only exacerbate hypoxic stress. However, certain cell populations maintain cell proliferation in the face of hypoxia. This is a common pathological hallmark of cancers, but can also serve a physiological function, as in the maintenance of stem cell populations that reside in a hypoxic niche. This review will discuss major molecular mechanisms by which hypoxia regulates cell proliferation in different cell populations, with a particular focus on the role of hypoxia-inducible factors. PMID:26491052

  2. Differential Glutamate Metabolism in Proliferating and Quiescent Mammary Epithelial Cells.

    PubMed

    Coloff, Jonathan L; Murphy, J Patrick; Braun, Craig R; Harris, Isaac S; Shelton, Laura M; Kami, Kenjiro; Gygi, Steven P; Selfors, Laura M; Brugge, Joan S

    2016-05-10

    Mammary epithelial cells transition between periods of proliferation and quiescence during development, menstrual cycles, and pregnancy, and as a result of oncogenic transformation. Utilizing an organotypic 3D tissue culture model coupled with quantitative metabolomics and proteomics, we identified significant differences in glutamate utilization between proliferating and quiescent cells. Relative to quiescent cells, proliferating cells catabolized more glutamate via transaminases to couple non-essential amino acid (NEAA) synthesis to α-ketoglutarate generation and tricarboxylic acid (TCA) cycle anaplerosis. As cells transitioned to quiescence, glutamine consumption and transaminase expression were reduced, while glutamate dehydrogenase (GLUD) was induced, leading to decreased NEAA synthesis. Highly proliferative human tumors display high transaminase and low GLUD expression, suggesting that proliferating cancer cells couple glutamine consumption to NEAA synthesis to promote biosynthesis. These findings describe a competitive and partially redundant relationship between transaminases and GLUD, and they reveal how coupling of glutamate-derived carbon and nitrogen metabolism can be regulated to support cell proliferation. PMID:27133130

  3. 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. PMID:24527373

  4. 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

  5. Quantifying the abnormal hemodynamics of sickle cell anemia

    NASA Astrophysics Data System (ADS)

    Lei, Huan; Karniadakis, George

    2012-02-01

    Sickle red blood cells (SS-RBC) exhibit heterogeneous morphologies and abnormal hemodynamics in deoxygenated states. A multi-scale model for SS-RBC is developed based on the Dissipative Particle Dynamics (DPD) method. Different cell morphologies (sickle, granular, elongated shapes) typically observed in deoxygenated states are constructed and quantified by the Asphericity and Elliptical shape factors. The hemodynamics of SS-RBC suspensions is studied in both shear and pipe flow systems. The flow resistance obtained from both systems exhibits a larger value than the healthy blood flow due to the abnormal cell properties. Moreover, SS-RBCs exhibit abnormal adhesive interactions with both the vessel endothelium cells and the leukocytes. The effect of the abnormal adhesive interactions on the hemodynamics of sickle blood is investigated using the current model. It is found that both the SS-RBC - endothelium and the SS-RBC - leukocytes interactions, can potentially trigger the vicious ``sickling and entrapment'' cycles, resulting in vaso-occlusion phenomena widely observed in micro-circulation experiments.

  6. 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.

  7. nr0b1 (DAX1) mutation in zebrafish causes female-to-male sex reversal through abnormal gonadal proliferation and differentiation.

    PubMed

    Chen, Sijie; Zhang, Hefei; Wang, Fenghua; Zhang, Wei; Peng, Gang

    2016-09-15

    Sex determinations are diverse in vertebrates. Although many sex-determining genes and pathways are conserved, the mechanistic roles of these genes and pathways in the genetic sex determination are not well understood. DAX1 (encoded by the NR0B1 gene) is a vertebrate specific orphan nuclear receptor that regulates gonadal development and sexual determination. In human, duplication of the NR0B1 gene leads to male-to-female sex reversal. In mice, Nr0b1 shows both pro-testis and anti-testis functions. We generated inheritable nr0b1 mutation in the zebrafish and found the nr0b1 mutation caused homozygous mutants to develop as fertile males due to female-to-male sex reversal. The nr0b1 mutation did not increase Caspase-3 labeling nor tp53 expression in the developing gonads. Introduction of a tp53 mutation into the nr0b1 mutant did not rescue the sex-reversal phenotype. Further examination revealed reduction in cell proliferation and abnormal somatic cell differentiation in the nr0b1 mutant gonads at the undifferentiated and bi-potential ovary stages. Together, our results suggest nr0b1 regulates somatic cell differentiation and cell proliferation to ensure normal sex development in the zebrafish. PMID:27267667

  8. Aberrant expression of laminin-332 promotes cell proliferation and cyst growth in ARPKD.

    PubMed

    Vijayakumar, Soundarapandian; Dang, Suparna; Marinkovich, M Peter; Lazarova, Zelmira; Yoder, Bradley; Torres, Vicente E; Wallace, Darren P

    2014-03-15

    Basement membrane abnormalities have often been observed in kidney cysts of polycystic kidney disease (PKD) patients and animal models. There is an abnormal deposition of extracellular matrix molecules, including laminin-α3,β3,γ2 (laminin-332), in human autosomal dominant PKD (ADPKD). Knockdown of PKD1 paralogs in zebrafish leads to dysregulated synthesis of the extracellular matrix, suggesting that altered basement membrane assembly may be a primary defect in ADPKD. In this study, we demonstrate that laminin-332 is aberrantly expressed in cysts and precystic tubules of human autosomal recessive PKD (ARPKD) kidneys as well as in the kidneys of PCK rats, an orthologous ARPKD model. There was aberrant expression of laminin-γ2 as early as postnatal day 2 and elevated laminin-332 protein in postnatal day 30, coinciding with the formation and early growth of renal cysts in PCK rat kidneys. We also show that a kidney cell line derived from Oak Ridge polycystic kidney mice, another model of ARPKD, exhibited abnormal lumen-deficient and multilumen structures in Matrigel culture. These cells had increased proliferation rates and altered expression levels of laminin-332 compared with their rescued counterparts. A function-blocking polyclonal antibody to laminin-332 significantly inhibited their abnormal proliferation rates and rescued their aberrant phenotype in Matrigel culture. Furthermore, abnormal laminin-332 expression in cysts originating from collecting ducts and proximal tubules as well as in precystic tubules was observed in a human end-stage ADPKD kidney. Our results suggest that abnormal expression of laminin-332 contributes to the aberrant proliferation of cyst epithelial cells and cyst growth in genetic forms of PKD. PMID:24370592

  9. ROLE OF CELLULAR BIOENERGETICS IN SMOOTH MUSCLE CELL PROLIFERATION INDUCED BY PLATELET-DERIVED GROWTH FACTOR

    PubMed Central

    Perez, Jessica; Hill, Bradford G.; Benavides, Gloria A.; Dranka, Brian P.; Darley-Usmar, Victor M.

    2013-01-01

    SYNOPSIS Abnormal smooth muscle cell proliferation is a hallmark of vascular disease. Although growth factors are known to contribute to cell hyperplasia, the changes in metabolism associated with this response, particularly mitochondrial respiration, remain unclear. Given the increased energy requirements for proliferation, we hypothesized that platelet-derived growth factor (PDGF) would stimulate glycolysis and mitochondrial respiration and that this elevated bioenergetic capacity is required for smooth muscle cell hyperplasia. To test this hypothesis, cell proliferation, glycolytic flux, and mitochondrial oxygen consumption were measured after treatment of primary rat aortic smooth muscle cells with PDGF. PDGF increased basal and maximal rates of glycolytic flux and mitochondrial oxygen consumption; enhancement of these bioenergetic pathways led to a substantial increase in the mitochondrial reserve capacity. Interventions with the PI3K inhibitor LY-294002 or the glycolysis inhibitor 2-deoxy-D-glucose abrogated PDGF-stimulated proliferation and prevented augmentation of glycolysis and mitochondrial reserve capacity. Similarly, when L-glucose was substituted for D-glucose, PDGF-dependent proliferation was abolished, as were changes in glycolysis and mitochondrial respiration. Interestingly, lactate dehydrogenase protein levels and activity were significantly increased after PDGF treatment. Moreover, L-lactate substitution for D-glucose was sufficient for increasing the mitochondrial reserve capacity and cell proliferation after treatment with PDGF; these effects were inhibited by the lactate dehydrogenase inhibitor, oxamate. These data suggest that glycolysis, by providing substrates that enhance the mitochondrial reserve capacity, plays an essential role in PDGF-induced cell proliferation, underscoring the integrated metabolic response required for proliferation of VSMC in the diseased vasculature. PMID:20331438

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

    PubMed

    Yu, Lingling; Zhao, Yingmin; Gu, Xin; Wang, Jijun; Pang, Lei; Zhang, Yanqing; Li, Yaoyao; Jia, Xiaoqin; Wang, Xin; Gu, Jian; Yu, Duonan

    2016-06-10

    Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feeder layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. PMID:26968634

  11. Human regulatory T cells suppress proliferation of B lymphoma cells.

    PubMed

    Grygorowicz, Monika Anna; Biernacka, Marzena; Bujko, Mateusz; Nowak, Eliza; Rymkiewicz, Grzegorz; Paszkiewicz-Kozik, Ewa; Borycka, Ilona Sara; Bystydzienski, Zbigniew; Walewski, Jan; Markowicz, Sergiusz

    2016-08-01

    Activated regulatory T cells (Tregs) suppress proliferation and differentiation of normal B cells. In our study, allogeneic polyclonal CD4 (+) CD25 (+) Tregs and CD4 (+) CD25 (+) CD127(lo)Tregs expanded in vitro in the presence of rapamycin and low dose IL-2 suppressed proliferation of 11 out of 12 established lymphoma B-cell lines. The effect of expanded CD4 (+) CD25 (+) Tregs on survival of freshly isolated lymphoma B cells maintained in culture with soluble multimeric CD40L and IL-4 was variable across lymphoma entities. The survival of freshly isolated follicular lymphoma cells usually decreased in cocultures with CD4 (+) CD25 (+) Tregs. Treg effect on chronic lymphocytic leukemia/small lymphocytic lymphoma cells ranged from suppression to help in individual patients. CD4 (+) CD25 (+) Tregs or CD4 (+) CD25 (+) CD127(lo)Tregs expanded ex vivo with rapamycin could be used to suppress regrowth of residual lymphoma after autologous hematopoietic cell transplantation (HCT), and to counteract both graft-versus-host disease and lymphoma re-growth after allogeneic HCT in select patients with lymphoma susceptible to the regulation by Tregs. PMID:26758248

  12. Cytomegalovirus infection associated with clonal proliferation of T-cell large granular lymphocytes: causal or casual?

    PubMed

    Wong, K F; Yip, S F; So, C C; Lau, G T C; Yeung, Y M

    2003-04-01

    Clonal proliferation of T-cell large granular lymphocytes (LGL) is an indolent disorder characterized by splenomegaly, lymphocytosis and frequent manifestations of immune disturbances. The LGL are CD3(+) CD4(-) CD8(+) CD56(-). The clonality of the tumor cell population is often only demonstrable by T-cell receptor (TCR) gene rearrangement study because chromosomal abnormality is distinctly rare. We describe a case of T-cell LGL leukemia that presented initially as cytomegalovirus infection. The leukemic LGL are shown to be clonal by both TCR gene rearrangement and chromosomal studies. They persist after subsidence of the cytomegalovirus infection. PMID:12660039

  13. 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

    2016-01-01

    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

  14. 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

  15. Effects of Abnormal Savda Munzip on the Proliferation Activity and Migration Ability of Fibroblasts Derived from Hypertrophic Scar In Vitro

    PubMed Central

    Wang, Hujun; Gao, Weicheng; Kong, Menglong; Li, Nan; Shaolin, Ma

    2015-01-01

    Background. To explore the effect of ASMq on proliferation and migration ability of the fibroblast derived from HS of donor (HSFbs) in vitro. Methods. The HSFbs were cultured from tissue specimens and passaged to the 3~4 generation, which were treated with the different concentrations of ASMq and 5-Fu from 1 to 11 days. The difference of HSFbs proliferation activity was analyzed by the CCK-8 method. The HSFbs migration ability in ASMq (0.4 mg/mL) was analyzed by the Cell Scratch method. Results. Transmission electron microscope result shows ASMq concentration significantly increases and fibroblast cell structure markedly change in the experimental group. The proliferation activity of the HSFbs was obviously weakened in ASMq groups than those of the group A (P < 0.05) at seven days. The group C (0.4 mg/mL) is better suitable than other three ASMq treatment groups. Cell Migration Assay shows that the migration ability HSFbs was significantly reduced in ASMq (0.4 mg/mL) treatment group compared with those of blank control group at both 24 h and 48 h (P < 0.05). Conclusions. These results suggest that ASMq effectively restrains the proliferation and migration ability of the HTSFbs in vitro, which can be one of the mechanisms for the prevention and treatment of HS. PMID:25821502

  16. 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

  17. Effects of thyroid hormones on human breast cancer cell proliferation.

    PubMed

    Hall, Linda C; Salazar, Eddie P; Kane, Staci R; Liu, Nan

    2008-03-01

    The involvement of estrogens in breast cancer development and growth has been well established. However, the effects of thyroid hormones and their combined effects with estrogens are not well studied. We investigated the response of human breast cancer cells to thyroid hormone, particularly the role of T3 in mediating cell proliferation and gene expression. We demonstrated that 17beta-estradiol (E2) or triiodothyronine (T3) promoted cell proliferation in a dose-dependent manner in both MCF-7 and T47-D cell lines. The E2- or T3-dependent cell proliferation was suppressed by co-administration of the ER antagonist ICI. We also demonstrated that T3 could enhance the effect of E2 on cell proliferation in T47-D cells. Using an estrogen response element (ERE)-mediated luciferase assay, we determined that T3 was able to induce the activation of ERE-mediated gene expression in MCF-7 cells, although the effects were much weaker than that induced by E2. These results suggest that T3 can promote breast cancer cell proliferation and increase the effect of E2 on cell proliferation in some breast cancer cell lines and thus that T3 may play a role in breast cancer development and progression. PMID:18328691

  18. Microenvironmental stimuli for proliferation of functional islet β-cells

    PubMed Central

    2014-01-01

    Diabetes is characterized by high blood glucose level due to either autoimmune destruction of islet β-cells or insufficient insulin secretion or glucose non-responsive production of insulin by β-cells. It is highly desired to replace biological functional β-cells for the treatment of diabetes. Unfortunately, β-cells proliferate with an extremely low rate. This cellular property hinders cell-based therapy for clinical application. Many attempts have been made to develop techniques that allow production of large quantities of clinically relevant islet β-cells in vitro. A line of studies evidently demonstrate that β-cells can proliferate under certain circumstances, giving the hopes for generating and expanding these cells in vitro and transplanting them to the recipient. In this review, we discuss the requirements of microenvironmental stimuli that stimulate β-cell proliferation in cell cultures. We highlight advanced approaches for augmentation of β-cell expansion that have recently emerged in this field. Furthermore, knowing the signaling pathways and molecular mechanisms would enable manipulating cell proliferation and optimizing its insulin secretory function. Thus, signaling pathways involved in the enhancement of cell proliferation are discussed as well. PMID:24594290

  19. Vitamin D inhibition of lung adenocarcinoma cell proliferation in vitro.

    PubMed

    Li, Rong; Lou, Yuqing; Zhang, Weiyan; Dong, Qianggang; Han, Baohui

    2014-11-01

    Vitamin D has the capability to inhibit tumor cell proliferation and promote tumor cell apoptosis but whether this mechanism exists in lung adenocarcinoma cells remains to be studied. Our objective is to explore whether vitamin D has the capability to inhibit lung adenocarcinoma cell proliferation and synergize with cisplatin. Our method was to explore the effect of different concentrations of 1,25(OH)2D3 with or without cisplatin on lung adenocarcinoma cells by detecting cell proliferation rates at different time points. 1,25(OH)2D3 was capsulated with nanomaterial before acting on lung adenocarcinoma cells, and cell proliferation rates at different time points were detected with the CCK-8 method. When vitamin D was applied at a concentration of 1 × 10(-7) and 1 × 10(-6) mol/L on A549, PC9, SPC-A1, and H1650 cells for 72 h, no inhibition occurred on cell proliferation. Between the concentrations of 1 × 10(-5) and 0.5 × 10(-5) mol/L, inhibition on cell proliferation increased with drug action time. Between the concentration of 2.5 × 10(-5) and 0.03 × 10(-5) mol/L, inhibition on cell proliferation increased with increasing drug concentration. Analysis using bivariate correlations showed that the correlation coefficient of the proliferation inhibition rate and drug content was 0.580 (p < 0.0001). The correlation coefficient of proliferation inhibition rate and the drug action time was 0.379 (p = 0.01). The combined use of vitamin D and dichlorodiammine-platinum(II) (DDP) significantly increased the inhibition rate on A549 cell proliferation, which peaked after culturing for 96 h (Table 4). Further analysis using bivariate correlations showed that the correlation coefficient between proliferation inhibition rate and DDP concentration was 0.319 (p < 0.0001). The correlation coefficient of the proliferation inhibition rate and vitamin D concentration was 0.269 (p < 0.0001). The correlation coefficient of proliferation inhibition and drug action time was 0.221(p

  20. 20-HETE Mediates Proliferation of Renal Epithelial Cells in Polycystic Kidney Disease

    PubMed Central

    Park, Frank; Sweeney, William E.; Jia, Guangfu; Roman, Richard J.; Avner, Ellis D.

    2008-01-01

    Polycystic kidney diseases are characterized by abnormal proliferation of renal epithelial cells. In this study, the role of 20-hydroxyeicosatetraenoic acid (20-HETE), an endogenous cytochrome P450 metabolite of arachidonic acid with mitogenic properties, was evaluated in cystic renal disease. Daily administration of HET-0016, an inhibitor of 20-HETE synthesis, significantly reduced kidney size by half in the BPK mouse model of autosomal recessive polycystic kidney disease. In addition, compared with untreated BPK mice, this treatment significantly reduced collecting tubule cystic indices and approximately doubled survival. For evaluation of the role of 20-HETE as a mediator of epithelial cell proliferation, principal cells isolated from cystic BPK and noncystic Balb/c mice were genetically modified using lentiviral vectors. Noncystic Balb/c cells overproducing Cyp4a12 exhibited a four- to five-fold increase in cell proliferation compared with control Balb/c cells, and this increase was completely abolished when 20-HETE synthesis was inhibited; therefore, this study suggests that 20-HETE mediates proliferation of epithelial cells in the formation of renal cysts. PMID:18596124

  1. Peroxisome proliferator-activated receptor gamma overexpression suppresses proliferation of human colon cancer cells

    SciTech Connect

    Tsukahara, Tamotsu; Haniu, Hisao

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer We examined the correlation between PPAR{gamma} expression and cell proliferation. Black-Right-Pointing-Pointer PPAR{gamma} overexpression reduces cell viability. Black-Right-Pointing-Pointer We show the synergistic effect of cell growth inhibition by a PPAR{gamma} agonist. -- Abstract: Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) plays an important role in the differentiation of intestinal cells and tissues. Our previous reports indicate that PPAR{gamma} is expressed at considerable levels in human colon cancer cells. This suggests that PPAR{gamma} expression may be an important factor for cell growth regulation in colon cancer. In this study, we investigated PPAR{gamma} expression in 4 human colon cancer cell lines, HT-29, LOVO, DLD-1, and Caco-2. Real-time polymerase chain reaction (PCR) and Western blot analysis revealed that the relative levels of PPAR{gamma} mRNA and protein in these cells were in the order HT-29 > LOVO > Caco-2 > DLD-1. We also found that PPAR{gamma} overexpression promoted cell growth inhibition in PPAR{gamma} lower-expressing cell lines (Caco-2 and DLD-1), but not in higher-expressing cells (HT-29 and LOVO). We observed a correlation between the level of PPAR{gamma} expression and the cells' sensitivity for proliferation.

  2. Rac1 drives intestinal stem cell proliferation and regeneration

    PubMed Central

    Myant, Kevin B; Scopelliti, Alessandro; Haque, Sara; Vidal, Marcos; Sansom, Owen J; Cordero, Julia B

    2013-01-01

    Adult stem cells are responsible for maintaining the balance between cell proliferation and differentiation within self-renewing tissues. The molecular and cellular mechanisms mediating such balance are poorly understood. The production of reactive oxygen species (ROS) has emerged as an important mediator of stem cell homeostasis in various systems. Our recent work demonstrates that Rac1-dependent ROS production mediates intestinal stem cell (ISC) proliferation in mouse models of colorectal cancer (CRC). Here, we use the adult Drosophila midgut and the mouse small intestine to directly address the role of Rac1 in ISC proliferation and tissue regeneration in response to damage. Our results demonstrate that Rac1 is necessary and sufficient to drive ISC proliferation and regeneration in an ROS-dependent manner. Our data point to an evolutionarily conserved role of Rac1 in intestinal homeostasis and highlight the value of combining work in the mammalian and Drosophila intestine as paradigms to study stem cell biology. PMID:23974108

  3. miR-21 promotes human nucleus pulposus cell proliferation through PTEN/AKT signaling.

    PubMed

    Liu, Hongzhe; Huang, Xiangwang; Liu, Xiangyang; Xiao, Sheng; Zhang, Yi; Xiang, Tiecheng; Shen, Xiongjie; Wang, Guoping; Sheng, Bin

    2014-01-01

    The precise role of nucleus pulposus cell proliferation in the pathogenesis of intervertebral disc degeneration remains to be elucidated. Recent findings have revealed that microRNAs, a class of small noncoding RNAs, may regulate cell proliferation in many pathological conditions. Here, we showed that miR-21 was significantly upregulated in degenerative nucleus pulposus tissues when compared with nucleus pulposus tissues that were isolated from patients with idiopathic scoliosis and that miR-10b levels were associated with disc degeneration grade. Moreover, bioinformatics target prediction identified PTEN as a putative target of miR-21. miR-21 inhibited PTEN expression by directly targeting the 3'UTR, and this inhibition was abolished through miR-21 binding site mutations. miR-21 overexpression stimulated cell proliferation and AKT signaling pathway activation, which led to cyclin D1 translation. Additionally, the increase in proliferation and cyclin D1 expression induced by miR-21 overexpression was almost completely blocked by Ly294002, an AKT inhibitor. Taken together, aberrant miR-21 upregulation in intervertebral disc degeneration could target PTEN, which would contribute to abnormal nucleus pulposus cell proliferation through derepressing the Akt pathway. Our study also underscores the potential of miR-21 and the PTEN/Akt pathway as novel therapeutic targets in intervertebral disc degeneration. PMID:24603539

  4. miR-21 Promotes Human Nucleus Pulposus Cell Proliferation through PTEN/AKT Signaling

    PubMed Central

    Liu, Hongzhe; Huang, Xiangwang; Liu, Xiangyang; Xiao, Sheng; Zhang, Yi; Xiang, Tiecheng; Shen, Xiongjie; Wang, Guoping; Sheng, Bin

    2014-01-01

    The precise role of nucleus pulposus cell proliferation in the pathogenesis of intervertebral disc degeneration remains to be elucidated. Recent findings have revealed that microRNAs, a class of small noncoding RNAs, may regulate cell proliferation in many pathological conditions. Here, we showed that miR-21 was significantly upregulated in degenerative nucleus pulposus tissues when compared with nucleus pulposus tissues that were isolated from patients with idiopathic scoliosis and that miR-10b levels were associated with disc degeneration grade. Moreover, bioinformatics target prediction identified PTEN as a putative target of miR-21. miR-21 inhibited PTEN expression by directly targeting the 3′UTR, and this inhibition was abolished through miR-21 binding site mutations. miR-21 overexpression stimulated cell proliferation and AKT signaling pathway activation, which led to cyclin D1 translation. Additionally, the increase in proliferation and cyclin D1 expression induced by miR-21 overexpression was almost completely blocked by Ly294002, an AKT inhibitor. Taken together, aberrant miR-21 upregulation in intervertebral disc degeneration could target PTEN, which would contribute to abnormal nucleus pulposus cell proliferation through derepressing the Akt pathway. Our study also underscores the potential of miR-21 and the PTEN/Akt pathway as novel therapeutic targets in intervertebral disc degeneration. PMID:24603539

  5. 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.

  6. High incidence of MYC and BCL2 abnormalities in mantle cell lymphoma, although only MYC abnormality predicts poor survival

    PubMed Central

    Li, Chengwen; Zhong, Shizhen; Chen, Weiwei; Li, Zengjun; Xiong, Wenjie; Liu, Wei; Liu, Enbin; Cui, Rui; Ru, Kun; Zhang, Peihong; Xu, Yan; An, Gang; Lv, Rui; Qi, Junyuan; Wang, Jianxiang; Cheng, Tao; Qiu, Lugui

    2015-01-01

    The incidence and prognostic role of MYC and BCL2 rearrangements in mature B-cell lymphomas have been extensively studied, except the infrequent mantle cell lymphoma (MCL). Here, we analyzed the MYC and BCL2 abnormalities and other cytogenetic aberrations by fluorescence in situ hybridization (FISH) in 50 MCL patients with bone marrow involvement. Eighteen patients (36.0%) had MYC gains and/or amplifications, and twelve patients (24.0%) had BCL2 gains and/or amplifications. Among the 18 patients with MYC abnormality, four had simultaneous MYC translocations, but no BCL2 translocation was detected among patients with BCL2 abnormality. Only two patients (4.0%) had both MYC and BCL2 abnormalities. The patients with a MYC abnormality had a significantly higher tumor burden, a higher percentage of medium/high risk MIPI group and genomic instability compared to those without this abnormality. However, no significant difference was observed between patients with or without a BCL2 abnormality in terms of clinical and cytogenetic factors. Patients with a MYC abnormality had poorer progress-free survival (PFS) (9.0 vs. 48.0 months, p = .000) and overall survival (OS) (12.0 vs. 94.5 months, p = .000), but the presence of a BCL2 abnormality did not significantly influence either PFS or OS. In multivariate analysis, the MYC abnormality was the independent adverse factor for both PFS and OS, and intensive chemotherapy did not improve the outcome of these patients. Thus, the presence of a MYC but not BCL2 abnormality predicted the poor survival of MCL patients, and a new treatment strategy should be developed for these patients. PMID:26517511

  7. Cell proliferation of Paramecium tetraurelia on a slow rotating clinostat

    NASA Astrophysics Data System (ADS)

    Sawai, Satoe; Mogami, Yoshihiro; Baba, Shoji A.

    Paramecium is known to proliferate faster under microgravity conditions, and slower under hypergravity. Experiments using axenic culture medium have demonstrated that hypergravity affected directly on the proliferation of Paramecium itself. In order to assess the mechanisms underlying the physiological effects of gravity on cell proliferation, Paramecium tetraurelia was grown under clinorotation (2.5 rpm) and the time course of the proliferation was investigated in detail on the basis of the logistic analysis. On the basis of the mechanical properties of Paramecium, this slow rate of the rotation appears to be enough to simulate microgravity in terms of the randomization of the cell orientation with respect to gravity. P. tetraurelia was cultivated in a closed chamber in which cells were confined without air bubbles, reducing the shear forces and turbulences under clinorotation. The chamber is made of quartz and silicone rubber film; the former is for the optically-flat walls for the measurement of cell density by means of a non-invasive laser optical-slice method, and the latter for gas exchange. Because of the small dimension for culture space, Paramecium does not accumulate at the top of the chamber in spite of its known negative gravitactic behavior. We measured the cell density at regular time intervals without breaking the configuration of the chamber, and analyzed the proliferation parameters by fitting the data to a logistic equation. As a result, P. tetraurelia showed reduced proliferation under slow clinorotation. The saturation of the cell density as well as the maximum proliferation rate decreased, although we found no significant changes on the half maximal time for proliferation. We also found that the mean swimming velocity decreased under slow clinorotation. These results were not consistent with those under microgravity and fast rotating clinostat. This may suggest that randomization of the cell orientation performed by slow rotating clinostat has

  8. Cell proliferation of Paramecium tetraurelia under simulated microgravity

    NASA Astrophysics Data System (ADS)

    Sawai, S.; Mogami, Y.; Baba, S. A.

    Paramecium is known to proliferate faster under microgravity in space and slower under hypergravity Experiments using axenic culture medium have demonstrated that the hypergravity affected directly on the proliferation of Paramecium itself Kato et al 2003 In order to assess the mechanisms underlying the physiological effects of gravity on cell proliferation Paramecium tetraurelia was grown under simulated microgravity performed by clinorotation and the time course of the proliferation was investigated in detail on the basis of the logistic analysis P tetraurelia was cultivated in a closed chamber in which cells were confined without air babbles reducing the shear stresses and turbulence under the rotation The chamber is made of quartz and silicone rubber film the former is for the optically-flat walls for the measurement of cell density by means of a non-invasive laser optical-slice method and the latter for gas exchange Because the closed chamber has an inner dimension of 3 times 3 times 60 mm Paramecium does not accumulate at the top of the chamber despite its negative gravitactic behavior We measured the cell density at regular time intervals without breaking the configuration of the chamber and analyzed the proliferation parameters by fitting the data to a logistic equation Clinorotation had the effects of reducing the proliferation of P tetraurelia It reduced both the saturation cell density and the maximum proliferation rate although it had little effect on the

  9. UNUSUAL EOSINOPHILIC GRANULE CELL PROLIFERATION IN COHO SALMON (ONCHORHYNCHUS KISUTCH)

    EPA Science Inventory

    Proliferative lesions comprised of eosinophilic granule cells (EGCs) extended throughout the gastrointestinal tract of several mature, spawning coho salmon Oncorhynchus kisutch (Walbaum). istological examination of the tumour showed extensive proliferation and infiltration of EGC...

  10. 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.

  11. 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.

  12. ETOPOSIDE INDUCES CHROMOSOMAL ABNORMALITIES IN SPERMATOCYTES AND SPERMATOGONIAL STEM CELLS

    SciTech Connect

    Marchetti, F; Pearson, F S; Bishop, J B; Wyrobek, A J

    2005-07-15

    Etoposide (ET) is a chemotherapeutic agent widely used in the treatment of leukemia, lymphomas and many solid tumors, such as testicular and ovarian cancers, that affect patients in their reproductive years. The purpose of the study was to use sperm FISH analyses to characterize the long-term effects of ET on male germ cells. We used a mouse model to characterize the induction of chromosomal aberrations (partial duplications and deletions) and whole chromosomal aneuploidies in sperm of mice treated with a clinical dose of ET. Semen samples were collected at 25 and 49 days after dosing to investigate the effects of ET on meiotic pachytene cells and spermatogonial stem-cells, respectively. ET treatment resulted in major increases in the frequencies of sperm carrying chromosomal aberrations in both meiotic pachytene (27- to 578-fold) and spermatogonial stem-cells (8- to 16-fold), but aneuploid sperm were induced only after treatment of meiotic cells (27-fold) with no persistent effects in stem cells. These results demonstrate that male meiotic germ cells are considerably more sensitive to ET than spermatogonial stem-cell and that increased frequencies of sperm with structural aberrations persist after spermatogonial stem-cell treatment. These findings predict that patients who undergo chemotherapy with ET may have transient elevations in the frequencies of aneuploid sperm, but more importantly, may have persistent elevations in the frequencies of sperm with chromosomal aberrations, placing them at higher risk for abnormal reproductive outcomes long after the end of their chemotherapy.

  13. 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. PMID:24244705

  14. 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

  15. [The implementation of computer model in research of dynamics of proliferation of cells of thyroid gland follicle].

    PubMed

    Abduvaliev, A A; Gil'dieva, M S; Khidirov, B N; Saĭdalieva, M; Khasanov, A A; Musaeva, Sh N; Saatov, T S

    2012-04-01

    The article deals with the results of computational experiments in research of dynamics of proliferation of cells of thyroid gland follicle in normal condition and in the case of malignant neoplasm. The model studies demonstrated that the chronic increase of parameter of proliferation of cells of thyroid gland follicle results in abnormal behavior of numbers of cell cenosis of thyroid gland follicle. The stationary state interrupts, the auto-oscillations occur with transition to irregular oscillations with unpredictable cell proliferation and further to the "black hole" effect. It is demonstrated that the present medical biologic experimental data and theory propositions concerning the structural functional organization of thyroid gland on cell level permit to develop mathematical models for quantitative analysis of numbers of cell cenosis of thyroid gland follicle in normal conditions. The technique of modeling of regulative mechanisms of living systems and equations of cell cenosis regulations was used PMID:22768711

  16. 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.

  17. 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.

  18. Proliferation of differentiated glial cells in the brain stem.

    PubMed

    Barradas, P C; Cavalcante, L A

    1998-02-01

    Classical studies of macroglial proliferation in muride rodents have provided conflicting evidence concerning the proliferating capabilities of oligodendrocytes and microglia. Furthermore, little information has been obtained in other mammalian orders and very little is known about glial cell proliferation and differentiation in the subclass Metatheria although valuable knowledge may be obtained from the protracted period of central nervous system maturation in these forms. Thus, we have studied the proliferative capacity of phenotypically identified brain stem oligodendrocytes by tritiated thymidine radioautography and have compared it with known features of oligodendroglial differentiation as well as with proliferation of microglia in the opossum Didelphis marsupialis. We have detected a previously undescribed ephemeral, regionally heterogeneous proliferation of oligodendrocytes expressing the actin-binding, ensheathment-related protein 2'3'-cyclic nucleotide 3'-phosphodiesterase (CNPase), that is not necessarily related to the known regional and temporal heterogeneity of expression of CNPase in cell bodies. On the other hand, proliferation of microglia tagged by the binding of Griffonia simplicifolia B4 isolectin, which recognizes an alpha-D-galactosyl-bearing glycoprotein of the plasma membrane of macrophages/microglia, is known to be long lasting, showing no regional heterogeneity and being found amongst both ameboid and differentiated ramified cells, although at different rates. The functional significance of the proliferative behavior of these differentiated cells is unknown but may provide a low-grade cell renewal in the normal brain and may be augmented under pathological conditions. PMID:9686148

  19. 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. PMID:26149574

  20. 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. PMID:27269880

  1. NDC80 promotes proliferation and metastasis of colon cancer cells.

    PubMed

    Xing, X K; Wu, H Y; Chen, H L; Feng, H G

    2016-01-01

    Chromosome instability is a common feature of tumor cells, and may be an important mechanism in tumor formation. Nuclear division cycle 80 (NDC80) is closely associated with the stability of chromosomes. Therefore, we investigated the relationship between NDC80 and development of colon cancer using a range of methods. Western blotting and immunohistochemistry were employed to determine the expression of this protein in different colon cells and tissues, cell proliferation was measured with an MTT assay, levels of proliferating cell nuclear antigen were examined by immunofluorescence, and cell migration was observed using wound healing tests. Our results showed that the expression of NDC80 in colon cancer cells (CACO2, HCT8, HCT116, and SW480) and tissues (from 20 patients) was higher than that in controls. Moreover, cell proliferation and migration rates were elevated in cells transfected with NDC80 compared to control groups. In summary, NDC80 promotes the proliferation and metastasis of colon cancer cells, and may constitute a new target for gene therapy in treating this disease. Combined with clinicopathological grading, measurement of positive NDC80 expression may be helpful in diagnosing and estimating the prognosis of colon cancer patients. PMID:27173328

  2. Mutation of p53 in squamous cell cancer of the head and neck: relationship to tumor cell proliferation.

    PubMed

    Wood, N B; Kotelnikov, V; Caldarelli, D D; Hutchinson, J; Panje, W R; Hegde, P; Leurgans, S; LaFollette, S; Taylor, S G; Preisler, H D; Coon, J S

    1997-06-01

    Rapid proliferation of squamous cell carcinomas of the head and neck (SCCHN) during therapy may contribute to treatment failure. We have investigated the presence of p53 abnormalities in patients with SCCHN as a correlate of proliferation rate and other pathologic and clinical variables. p53 Mutation, as determined by polymerase chain reaction and single-strand conformation polymorphism analysis of microdissected frozen sections of tumor biopsies, was significantly associated with a high labeling index, as determined by in vivo infusion of IUdR and BrdU (P = 0.017). p53 Protein expression was detected by immunohistochemistry with two different antibodies, followed by quantitative image analysis. Many cases exhibited strong p53 protein expression in the absence of mutations within the conserved region of the gene, and expression was not related to proliferation. The presence of p53 mutations was related to tumor differentiation in this group of patients. PMID:9185741

  3. Tenuigenin promotes proliferation and differentiation of hippocampal neural stem cells.

    PubMed

    Chen, Yujing; Huang, Xiaobo; Chen, Wenqiang; Wang, Ningqun; Li, Lin

    2012-04-01

    The present study was to investigate the influence of tenuigenin, an active ingredient of Polygala tenuifolia Willd, on the proliferation and differentiation of hippocampal neural stem cells in vitro. Tenuigenin was added to a neurosphere culture and neurosphere growth was measured using MTT assay. The influence of tenuigenin on the proliferation of neural progenitors was examined by Clone forming assay and BrdU detection. In addition, the differentiation of neural stem cells was compared using immunocytochemistry for β III-tubulin and GFAP. The results showed that addition of tenuigenin to the neural stem cell medium increased the number of newly formed neurospheres. More neurons were also obtained when tenuigenin was added in the differentiation medium. These findings suggest that tenuigenin is involved in regulating the proliferation and differentiation of hippocampal neural stem cells. This result may be one of the underlying reasons for tenuigenin's nootropic and anti-aging effects. PMID:22179853

  4. Sensitivity of proliferating human breast epithelial cells to hypotonic treatment

    SciTech Connect

    Goldstone, S.E.; Stanyon, R.; Lan, S.

    1982-12-01

    An assay for colony-forming cells of breast epithelia derived from normal and malignant surgical specimens is described using an IMR 90 fibroblast feeder layer. Their radiosensitivity (DO: 120-172) is consistent with the proliferative origin of the colonies. Distilled water inhibits proliferation of a proportion of the colony-forming cells after a 1-minute exposure. Continued detection of colonies after 10 minutes of exposure indicates that it is an inefficient way of completely eradicating proliferating epithelial cells of normal and malignant origin.

  5. Neuropeptide Y directly affects ovarian cell proliferation and apoptosis.

    PubMed

    Sirotkin, Alexander V; Kardošová, Diana; Alwasel, Saleh Hamad; Harrath, Abdel Halim

    2015-12-01

    The effects of neuropeptide Y (NPY; 0, 10, 100 and 1000 ng/mL) on the expression of PCNA, bax and p53 were examined by immunocytochemistry in porcine luteinized granulosa cells. NPY inhibited proliferation as well as promoted apoptosis and accumulation of p53 in the cells. This is the first report to demonstrate the direct action of NPY on ovarian cell proliferation and apoptosis. The results of the study suggest that the effect is mediated by transcription factor p53. PMID:26679167

  6. Retinoic acid specifically downregulates Fgf4 and inhibits posterior cell proliferation in the developing mouse autopod

    PubMed Central

    HAYES, CHRISTOPHER; MORRISS-KAY, GILLIAN M.

    2001-01-01

    Retinoic acid, when administered to pregnant mice on d 11.0 of gestation, causes limb skeletal abnormalities consisting of reduced digital number, shortening of the long bones and delayed ossification. We show here that these effects are correlated with a decrease in cell proliferation within 5 h of retinoic acid administration, specifically in the posterior half of the distal limb bud mesenchyme, from which the distal skeletal elements are generated. There is a specific downregulation of Fgf4, a gene known to be involved in limb bud outgrowth and expressed only in the posterior part of the apical ectodermal ridge; Fgf8, which is expressed throughout the apical ectodermal ridge, is unaffected. The reduction in Fgf4 expression is not accompanied by downregulation of Shh, nor of its receptor and downstream target gene Ptc, suggesting that the skeletal reduction defects induced by retinoic acid are mediated specifically by FGF4-induced skeletogenic mesenchymal cell proliferation. PMID:11430695

  7. EGFR signaling regulates cell proliferation, differentiation and morphogenesis during planarian regeneration and homeostasis.

    PubMed

    Fraguas, Susanna; Barberán, Sara; Cebrià, Francesc

    2011-06-01

    Similarly to development, the process of regeneration requires that cells accurately sense and respond to their external environment. Thus, intrinsic cues must be integrated with signals from the surrounding environment to ensure appropriate temporal and spatial regulation of tissue regeneration. Identifying the signaling pathways that control these events will not only provide insights into a fascinating biological phenomenon but may also yield new molecular targets for use in regenerative medicine. Among classical models to study regeneration, freshwater planarians represent an attractive system in which to investigate the signals that regulate cell proliferation and differentiation, as well as the proper patterning of the structures being regenerated. Recent studies in planarians have begun to define the role of conserved signaling pathways during regeneration. Here, we extend these analyses to the epidermal growth factor (EGF) receptor pathway. We report the characterization of three epidermal growth factor (EGF) receptors in the planarian Schmidtea mediterranea. Silencing of these genes by RNA interference (RNAi) yielded multiple defects in intact and regenerating planarians. Smed-egfr-1(RNAi) resulted in decreased differentiation of eye pigment cells, abnormal pharynx regeneration and maintenance, and the development of dorsal outgrowths. In contrast, Smed-egfr-3(RNAi) animals produced smaller blastemas associated with abnormal differentiation of certain cell types. Our results suggest important roles for the EGFR signaling in controlling cell proliferation, differentiation and morphogenesis during planarian regeneration and homeostasis. PMID:21458439

  8. Cell Proliferation in Cubozoan Jellyfish Tripedalia cystophora and Alatina moseri

    PubMed Central

    Gurska, Daniela; Garm, Anders

    2014-01-01

    Cubozoans (box jellyfish) undergo remarkable body reorganization throughout their life cycle when, first, they metamorphose from swimming larvae to sessile polyps, and second, through the metamorphosis from sessile polyps to free swimming medusae. In the latter they develop complex structures like the central nervous system (CNS) and visual organs. In the present study several aspects of cell proliferation at different stages of the life cycle of the box jellyfish Tripedalia cystophora and Alatina moseri have been examined through in vivo labeling of cells in the synthetic phase (S phase) of the cell cycle. Proliferation zones were found in metamorphosing polyps, as well as in juvenile medusae, where both the rhopalia and pedalia have enhanced rates of proliferation. The results also indicate a rather fast cell turnover in the rhopalia including the rhopalial nervous system (RNS). Moreover, T. cystophora showed diurnal pattern of cell proliferation in certain body parts of the medusa, with higher proliferation rates at nighttime. This is true for two areas in close connection with the CNS: the stalk base and the rhopalia. PMID:25047715

  9. Nerve growth factor enhances Clara cell proliferation after lung injury.

    PubMed

    Sonar, S S; Schwinge, D; Kilic, A; Yildirim, A O; Conrad, M L; Seidler, K; Müller, B; Renz, H; Nockher, W A

    2010-07-01

    The lung epithelia facilitate wound closure by secretion of various cytokines and growth factors. Nerve growth factor (NGF) has been well described in airway inflammation; however, its likely role in lung repair has not been examined thus far. To investigate the repair function of NGF, experiments were performed in vitro using cultured alveolar epithelial cells and in vivo using a naphthalene-induced model of Clara epithelial cell injury. Both in vitro and in vivo experiments revealed airway epithelial cell proliferation following injury to be dependent on NGF and the expression of its receptor, tropomyosin-receptor-kinase A. Additionally, NGF also augmented in vitro migration of alveolar type II cells. In vivo, transgenic mice over-expressing NGF in Clara cells (NGFtg) did not reveal any proliferation or alteration in Clara cell phenotype. However, following Clara cell specific injury, proliferation was increased in NGFtg and impaired upon inhibition of NGF. Furthermore, NGF also promoted the expression of collagen I and fibronectin in vitro and in vivo during repair, where significantly higher levels were measured in re-epithelialising NGFtg mice. Our study demonstrates that NGF promotes the proliferation of lung epithelium in vitro and the renewal of Clara cells following lung injury in vivo. PMID:20075049

  10. MiR-15b mediates liver cancer cells proliferation through targeting BCL-2

    PubMed Central

    Zhang, Yuping; Huang, Feizhou; Wang, Jian; Peng, Lin; Luo, Hongwu

    2015-01-01

    The incidence and mortality of liver cancer increased year by year. Our country presents high incidence of liver cancer. MicroRNAs have tissue sensitivity as tumor biomarkers that play a role by promoting tumor growth as oncogenes or inhibit malignant cell growth as tumor suppressor genes. Studies showed that miR-15b abnormal expression in the tumor and can be treated as one of the tumor molecular markers. However, miR-15b expression and role in the liver cancer cells have not been elucidated. This study intended to explore the mechanism of miR-15b effect on liver cancer occurrence and development. Liver cancer cell line HepG2 was transfected with miR-15b mimic or inhibitor. Real-time PCR was applied to detect miR-15b expression. MTT was used to test cell proliferation. Transwell assay was performed to determine cell invasive ability. Real-time PCR and Western blot were used to detect BCL2 expression. MiR-15b mimic transfection promoted miR-15b overexpression and inhibited HepG2 cell proliferation significantly (P < 0.05). MiR-15b overexpression downregulated BCL2 mRNA and protein expression obviously (P < 0.05). On the contrary, miR-15b inhibitor transfection markedly reduced miR-15b expression in liver cancer cells (P < 0.05), promoted tumor cell proliferation, and increased BCL2 mRNA and protein expression. MiR-15b expression changes did not affect cell invasion (P > 0.05). MiR-15b can inhibit HepG2 cell proliferation and down-regulate BCL2 mRNA and protein expression. PMID:26884837

  11. 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

  12. Proliferating cell nuclear antigen: a marker for hepatocellular proliferation in rodents.

    PubMed

    Eldrige, S R; Butterworth, B E; Goldsworthy, T L

    1993-12-01

    Two different markers for quantitating cell proliferation were evaluated in livers of control and chemically treated mice and rats. Proliferating cell nuclear antigen (PCNA), an endogenous cell replication marker, and bromodeoxyuridine (BrdU), an exogenously administered DNA precursor label, were detected in formalin-fixed, paraffin-embedded tissues using immunohistochemical techniques. The percentage of cells in S phase (labeling indexes, LI) evaluated as PCNA- or BrdU-positive hepatocellular nuclei was compared in recut tissue sections from animals given BrdU by a single IP injection 2 hr before killing the animals. Ten-week-old male B6C3F1 mice and F344 rats were exposed to known mitogenic hepatocarcinogens, Wy-14,643 (WY) in the diet at 0.1% for 2 days or 1,4-dichlorobenzene (DCB) in corn oil by gavage for 2 days (600 mg/kg/day in mice; 300 mg/kg/day in rats). In mice, PCNA and BrdU hepatocyte LI were similar in control, WY-treated, and DCB-treated animals. In rats, PCNA and BrdU gave similar LI in controls and Wy-treated animals. Although PCNA LI was statistically lower than BrdU LI in DCB-treated rats, both PCNA and BrdU LI for DCB-treated rats was increased over LI in control rats. Different patterns of PCNA immunohistochemical staining, interpreted to represent different subpopulations of cells at various phases of the cell cycle, were quantitated using PCNA immunohistochemistry. The proliferating index (PI), defined as the percentage of cells in the cell cycle (G1 + S + G2 + M), was more sensitive than the LI (S phase only) in detecting a chemically induced cell proliferative response.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7912188

  13. 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.

  14. Software for precise tracking of cell proliferation.

    PubMed

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

    2012-01-20

    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. PMID:22226970

  15. Electrospun fiber membranes enable proliferation of genetically modified cells

    PubMed Central

    Borjigin, Mandula; Eskridge, Chris; Niamat, Rohina; Strouse, Bryan; Bialk, Pawel; Kmiec, Eric B

    2013-01-01

    Polycaprolactone (PCL) and its blended composites (chitosan, gelatin, and lecithin) are well-established biomaterials that can enrich cell growth and enable tissue engineering. However, their application in the recovery and proliferation of genetically modified cells has not been studied. In the study reported here, we fabricated PCL-biomaterial blended fiber membranes, characterized them using physicochemical techniques, and used them as templates for the growth of genetically modified HCT116-19 colon cancer cells. Our data show that the blended polymers are highly miscible and form homogenous electrospun fiber membranes of uniform texture. The aligned PCL nanofibers support robust cell growth, yielding a 2.5-fold higher proliferation rate than cells plated on standard plastic plate surfaces. PCL-lecithin fiber membranes yielded a 2.7-fold higher rate of proliferation, while PCL-chitosan supported a more modest growth rate (1.5-fold higher). Surprisingly, PCL-gelatin did not enhance cell proliferation when compared to the rate of cell growth on plastic surfaces. PMID:23467983

  16. Impact of 5-azacytidine on rat decidual cell proliferation.

    PubMed

    Fabijanovic, Dora; Serman, Alan; Jezic, Marin; Katusic, Ana; Sincic, Nino; Curkovic-Perica, Mirna; Bulic-Jakus, Floriana; Vlahovic, Maja; Juric-Lekic, Gordana; Serman, Ljiljana

    2014-08-01

    The DNA demethylating agent 5-azacytidine (5-azaC) has a teratogenic influence during rat development influencing both the embryo and the placenta. Our aim was to investigate its impact on early decidual cell proliferation before the formation of placenta. Thus, female Fischer rats received 5-azaC (5 mg/kg, i.p.) on the 2nd, 5th or 8th day of gestation and the decidual tissues were harvested on gestation day 9. They were then analysed immunohistochemically for expression of cell proliferation marker proliferating cell nuclear antigen (PCNA) in decidual cells and for global DNA methylation using the coupled restriction enzyme digestion, random amplification and pyrosequencing assays. We found that 5-azaC administered on the 5th and 8th (but not on 2nd) day of gestation led to increased PCNA expression in decidual cells compared with untreated controls. No significant changes in DNA methylation were detected, with either method, in any of the treated rat groups compared with untreated controls. Thus, we conclude that 5-azaC can stimulate decidual cell proliferation without simultaneously changing global DNA methylation level in treated cells. PMID:24945576

  17. Impact of 5-azacytidine on rat decidual cell proliferation

    PubMed Central

    Fabijanovic, Dora; Serman, Alan; Jezic, Marin; Katusic, Ana; Sincic, Nino; Curkovic-Perica, Mirna; Bulic-Jakus, Floriana; Vlahovic, Maja; Juric-Lekic, Gordana; Serman, Ljiljana

    2014-01-01

    The DNA demethylating agent 5-azacytidine (5-azaC) has a teratogenic influence during rat development influencing both the embryo and the placenta. Our aim was to investigate its impact on early decidual cell proliferation before the formation of placenta. Thus, female Fischer rats received 5-azaC (5 mg/kg, i.p.) on the 2nd, 5th or 8th day of gestation and the decidual tissues were harvested on gestation day 9. They were then analysed immunohistochemically for expression of cell proliferation marker proliferating cell nuclear antigen (PCNA) in decidual cells and for global DNA methylation using the coupled restriction enzyme digestion, random amplification and pyrosequencing assays. We found that 5-azaC administered on the 5th and 8th (but not on 2nd) day of gestation led to increased PCNA expression in decidual cells compared with untreated controls. No significant changes in DNA methylation were detected, with either method, in any of the treated rat groups compared with untreated controls. Thus, we conclude that 5-azaC can stimulate decidual cell proliferation without simultaneously changing global DNA methylation level in treated cells. PMID:24945576

  18. Sonic Hedgehog promotes proliferation of Notch-dependent monociliated choroid plexus tumour cells.

    PubMed

    Li, Li; Grausam, Katie B; Wang, Jun; Lun, Melody P; Ohli, Jasmin; Lidov, Hart G W; Calicchio, Monica L; Zeng, Erliang; Salisbury, Jeffrey L; Wechsler-Reya, Robert J; Lehtinen, Maria K; Schüller, Ulrich; Zhao, Haotian

    2016-04-01

    Aberrant Notch signalling has been linked to many cancers including choroid plexus (CP) tumours, a group of rare and predominantly paediatric brain neoplasms. We developed animal models of CP tumours, by inducing sustained expression of Notch1, that recapitulate properties of human CP tumours with aberrant NOTCH signalling. Whole-transcriptome and functional analyses showed that tumour cell proliferation is associated with Sonic Hedgehog (Shh) in the tumour microenvironment. Unlike CP epithelial cells, which have multiple primary cilia, tumour cells possess a solitary primary cilium as a result of Notch-mediated suppression of multiciliate differentiation. A Shh-driven signalling cascade in the primary cilium occurs in tumour cells but not in epithelial cells. Lineage studies show that CP tumours arise from monociliated progenitors in the roof plate characterized by elevated Notch signalling. Abnormal SHH signalling and distinct ciliogenesis are detected in human CP tumours, suggesting the SHH pathway and cilia differentiation as potential therapeutic avenues. PMID:26999738

  19. Six2 Is a Coordinator of LiCl-Induced Cell Proliferation and Apoptosis.

    PubMed

    Liu, Jianing; Ju, Pan; Zhou, Yuru; Zhao, Ya; Xie, Yajun; Long, Yaoshui; Gu, Yuping; Ni, Dongsheng; Lyv, Zhongshi; Mao, Zhaomin; Hao, Jin; Li, Yiman; Wan, Qianya; Kanyomse, Quist; Liu, Yamin; Xiang, Yue; Wang, Ruoli; Chen, Xiangling; Zhang, Junman; Liu, Xihan; Zhao, Hui; Zhou, Qin; Li, Ge

    2016-01-01

    The metanephric mesenchyme (MM) cells are a subset of kidney progenitor cells and play an essential role in mesenchymal-epithelial transition (MET), the key step of nephron generation. Six2, a biological marker related to Wnt signaling pathway, promotes the proliferation, inhibits the apoptosis and maintains the un-differentiation of MM cells. Besides, LiCl is an activator of Wnt signaling pathway. However, the role of LiCl in cellular regulation of MM cells remains unclear, and the relationship between LiCl and Six2 in this process is also little known. Here, we performed EdU assay and flow cytometry assay to, respectively, detect the proliferation and apoptosis of MM cells treated with LiCl of increasing dosages. In addition, reverse transcription-PCR (RT-PCR) and Western-blot were conducted to measure the expression of Six2 and some maker genes of Wnt and bone-morphogenetic-protein (BMP) signaling pathway. Furthermore, luciferase assay was also carried out to detect the transcriptional regulation of Six2. Then we found LiCl promoted MM cell proliferation at low-concentration (10, 20, 30, and 40 mM). The expression of Six2 was dose-dependently increased in low-concentration (10, 20, 30, and 40 mM) at both mRNA and protein level. In addition, both of cell proliferation and Six2 expression in MM cells declined when dosage reached high-concentration (50 mM). However, Six2 knock-down converted the proliferation reduction at 50 mM. Furthermore, Six2 deficiency increased the apoptosis of MM cells, compared with negative control cells at relative LiCl concentration. However, the abnormal rise of apoptosis at 30 mM of LiCl concentration implies that it might be the reduction of GSK3β that increased cell apoptosis. Together, these demonstrate that LiCl can induce the proliferation and apoptosis of MM cells coordinating with Six2. PMID:27618015

  20. Phenobarbital-induced hepatocellular proliferation: anti-bromodeoxyuridine and anti-proliferating cell nuclear antigen immunocytochemistry.

    PubMed

    Jones, H B; Clarke, N A; Barrass, N C

    1993-01-01

    We report modifications to immunocytochemical detection procedures for proliferating cell nuclear antigen (PCNA) which permit its identification in liver samples previously fixed for BrdU immunocytochemistry. Both methods have been used for the assessment of phenobarbital-induced cell proliferation in rat liver. The difficulties associated with the hitherto unsuccessful application of PCNA immunocytochemical methods to tissues fixed in formalin for BrdU visualization were overcome by epitope unmasking with acid hydrolysis, extension of primary antiserum (PC10) incubation, and employment of streptavidin-ABC-HRP. BrdU delivery via osmotic minipumps for 48 hr before euthanasia, followed by fixation in cold formalin for 14 days, yielded reliable and reproducible hepatocellular labeling and a peak of cell proliferation in all lobes on Day 3 (i.e., labeling during Days 1-3) of dosing with 80 mg/kg/day phenobarbital. Labeling indices (LI) of both control and phenobarbital-treated liver were lower in the left and right median lobes as compared with the lateral lobes. In sections of the left lateral lobe from the same liver, PCNA immunocytochemistry revealed a peak of proliferative activity (about one third of the maximum LI generated by BrdU incorporation) on Day 1. These findings, together with the advantages and disadvantages of both techniques, are discussed in the context of their applications to different investigative requirements. PMID:8093255

  1. The Hippo Pathway Controls a Switch between Retinal Progenitor Cell Proliferation and Photoreceptor Cell Differentiation in Zebrafish

    PubMed Central

    Asaoka, Yoichi; Hata, Shoji; Namae, Misako; Furutani-Seiki, Makoto; Nishina, Hiroshi

    2014-01-01

    The precise regulation of numbers and types of neurons through control of cell cycle exit and terminal differentiation is an essential aspect of neurogenesis. The Hippo signaling pathway has recently been identified as playing a crucial role in promoting cell cycle exit and terminal differentiation in multiple types of stem cells, including in retinal progenitor cells. When Hippo signaling is activated, the core Mst1/2 kinases activate the Lats1/2 kinases, which in turn phosphorylate and inhibit the transcriptional cofactor Yap. During mouse retinogenesis, overexpression of Yap prolongs progenitor cell proliferation, whereas inhibition of Yap decreases this proliferation and promotes retinal cell differentiation. However, to date, it remains unknown how the Hippo pathway affects the differentiation of distinct neuronal cell types such as photoreceptor cells. In this study, we investigated whether Hippo signaling regulates retinogenesis during early zebrafish development. Knockdown of zebrafish mst2 induced early embryonic defects, including altered retinal pigmentation and morphogenesis. Similar abnormal retinal phenotypes were observed in zebrafish embryos injected with a constitutively active form of yap [(yap (5SA)]. Loss of Yap’s TEAD-binding domain, two WW domains, or transcription activation domain attenuated the retinal abnormalities induced by yap (5SA), indicating that all of these domains contribute to normal retinal development. Remarkably, yap (5SA)-expressing zebrafish embryos displayed decreased expression of transcription factors such as otx5 and crx, which orchestrate photoreceptor cell differentiation by activating the expression of rhodopsin and other photoreceptor cell genes. Co-immunoprecipitation experiments revealed that Rx1 is a novel interacting partner of Yap that regulates photoreceptor cell differentiation. Our results suggest that Yap suppresses the differentiation of photoreceptor cells from retinal progenitor cells by repressing Rx1

  2. Gedunin, a novel natural substance, inhibits ovarian cancer cell proliferation.

    PubMed

    Kamath, Siddharth G; Chen, Ning; Xiong, Yin; Wenham, Robert; Apte, Sachin; Humphrey, Marcia; Cragun, Janiel; Lancaster, Johnathan M

    2009-12-01

    The discovery of more active therapeutic compounds is essential if the outcome for patients with advanced-stage epithelial ovarian cancer is to be improved. Gedunin, an extract of the neem tree, has been used as a natural remedy for centuries in Asia. Recently, gedunin has been shown to have potential in vitro antineoplastic properties; however, its effect on ovarian cancer cells is unknown. We evaluated the in vitro effect of gedunin on SKOV3, OVCAR4, and OVCAR8 ovarian cancer cell lines proliferation, alone and in the presence of cisplatin. Furthermore, we analyzed in vitro gedunin sensitivity data, integrated with genome-wide expression data from 54 cancer cell lines in an effort to identify genes and molecular pathways that underlie the mechanism of gedunin action. In vitro treatment of ovarian cancer cell lines with gedunin alone produced up to an 80% decrease in cell proliferation (P < 0.01) and, combining gedunin with cisplatin, demonstrated up to a 47% (P < 0.01) decrease in cell proliferation compared with cisplatin treatment alone. Bioinformatic analysis of integrated gedunin sensitivity and gene expression data identified 52 genes to be associated with gedunin sensitivity. These genes are involved in molecular functions related to cell cycle control, carcinogenesis, lipid metabolism, and molecular transportation. We conclude that gedunin has in vitro activity against ovarian cancer cells and, further, may enhance the antiproliferative effect of cisplatin. The molecular determinants of in vitro gedunin response are complex and may include modulation of cell survival and apoptosis pathways. PMID:19955938

  3. Novel factors modulating human β-cell proliferation.

    PubMed

    Shirakawa, J; Kulkarni, R N

    2016-09-01

    β-Cell dysfunction in type 1 and type 2 diabetes is accompanied by a progressive loss of β-cells, and an understanding of the cellular mechanism(s) that regulate β-cell mass will enable approaches to enhance hormone secretion. It is becoming increasingly recognized that enhancement of human β-cell proliferation is one potential approach to restore β-cell mass to prevent and/or cure type 1 and type 2 diabetes. While several reports describe the factor(s) that enhance β-cell replication in animal models or cell lines, promoting effective human β-cell proliferation continues to be a challenge in the field. In this review, we discuss recent studies reporting successful human β-cell proliferation including WS6, an IkB kinase and EBP1 inhibitor; harmine and 5-IT, both DYRK1A inhibitors; GNF7156 and GNF4877, GSK-3β and DYRK1A inhibitors; osteoprotegrin and Denosmab, receptor activator of NF-kB (RANK) inhibitors; and SerpinB1, a protease inhibitor. These studies provide important examples of proteins and pathways that may prove useful for designing therapeutic strategies to counter the different forms of human diabetes. PMID:27615134

  4. 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.

  5. The cell proliferation antigen Ki-67 organises heterochromatin.

    PubMed

    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. PMID:26949251

  6. 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

  7. Simvastatin modulates mesenchymal stromal cell proliferation and gene expression.

    PubMed

    Zanette, Dalila Lucíola; Lorenzi, Julio Cesar Cetrulo; Panepucci, Rodrigo Alexandre; Palma, Patricia Vianna Bonini; Dos Santos, Daiane Fernanda; Prata, Karen Lima; Silva, Wilson Araújo

    2015-01-01

    Statins are widely used hypocholesterolemic drugs that block the mevalonate pathway, responsible for the biosysnthesis of cholesterol. However, statins also have pleiotropic effects that interfere with several signaling pathways. Mesenchymal stromal cells (MSC) are a heterogeneous mixture of cells that can be isolated from a variety of tissues and are identified by the expression of a panel of surface markers and by their ability to differentiate in vitro into osteocytes, adipocytes and chondrocytes. MSC were isolated from amniotic membranes and bone marrows and characterized based on ISCT (International Society for Cell Therapy) minimal criteria. Simvastatin-treated cells and controls were directly assayed by CFSE (Carboxyfluorescein diacetate succinimidyl ester) staining to assess their cell proliferation and their RNA was used for microarray analyses and quantitative PCR (qPCR). These MSC were also evaluated for their ability to inhibit PBMC (peripheral blood mononuclear cells) proliferation. We show here that simvastatin negatively modulates MSC proliferation in a dose-dependent way and regulates the expression of proliferation-related genes. Importantly, we observed that simvastatin increased the percentage of a subset of smaller MSC, which also were actively proliferating. The association of MSC decreased size with increased pluripotency and the accumulating evidence that statins may prevent cellular senescence led us to hypothesize that simvastatin induces a smaller subpopulation that may have increased ability to maintain the entire pool of MSC and also to protect them from cellular senescence induced by long-term cultures/passages in vitro. These results may be important to better understand the pleiotropic effects of statins and its effects on the biology of cells with regenerative potential. PMID:25874574

  8. Essential components for ex vivo proliferation of mesenchymal stromal cells.

    PubMed

    Fekete, Natalie; Rojewski, Markus Thomas; Lotfi, Ramin; Schrezenmeier, Hubert

    2014-02-01

    Mesenchymal stromal cells (MSCs) are highly interesting candidates for clinical applications in regenerative medicine. Due to their low occurrence in human tissues, extensive in vitro expansion is necessary to obtain sufficient cell numbers applicable as a clinical dose in the context of cellular therapy. Current cell culture media formulations for the isolation and expansion of MSCs include fetal calf serum (FCS), human AB serum (ABS), or human platelet lysate (PL) as a supplement. However, these established supplements are inherently ill-defined formulations that contain a variety of bioactive molecules in varying batch-to-batch compositions and the risk of transmitting pathogens that escape routine screening procedures. In this study, we have comparatively characterized the capacity of commonly used basal media, such as the Minimum Essential Medium alpha (αMEM), Dulbecco's modified Eagle's medium (DMEM), Iscove's Modified Dulbecco's Medium (IMDM), and RPMI 1640 as well as human- and animal-derived supplements, that is, PL, ABS, and FCS to stimulate cell proliferation. MSC proliferation was observed to be optimal in the PL-supplemented αMEM. Using a combinatorial approach, we then assessed a library of soluble factors, including mitogens (TGF-β1, Activin A, bFGF, EGF, IGF-I, PDGF-BB, and VEGF), chemokines (CCL21, CCL25, CXCL12, and RANTES), proteins (human serum albumin), lipids (e.g., oleic acid, linoleic acid, and arachidonic acid), and hormones (dexamethasone, insulin, and TSH), to create a defined medium as well as coating of cell culture surfaces to promote robust MSC proliferation in vitro. A combination of recombinant human factors partially met the nutritional requirements of bone marrow-derived MSCs, and was able to promote cell proliferation comparable to about 5% PL if supplemented with auxiliary 0.6%-1.2% PL. Maximal MSC proliferation was achieved by combining 5% PL with a cocktail of recombinant factors and did not depend on coating of cell

  9. Capsaicin modulates proliferation, migration, and activation of hepatic stellate cells.

    PubMed

    Bitencourt, Shanna; Mesquita, Fernanda; Basso, Bruno; Schmid, Júlia; Ferreira, Gabriela; Rizzo, Lucas; Bauer, Moises; Bartrons, Ramon; Ventura, Francesc; Rosa, Jose Luis; Mannaerts, Inge; van Grunsven, Leo Adrianus; Oliveira, Jarbas

    2014-03-01

    Capsaicin, the active component of chili pepper, has been reported to have antiproliferative and anti-inflammatory effects on a variety of cell lines. In the current study, we aimed to investigate the effects of capsaicin during HSC activation and maintenance. Activated and freshly isolated HSCs were treated with capsaicin. Proliferation was measured by incorporation of EdU. Cell cycle arrest and apoptosis were investigated using flow cytometry. The migratory response to chemotactic stimuli was evaluated by a modified Boyden chamber assay. Activation markers and inflammatory cytokines were determined by qPCR, immunocytochemistry, and flow cytometry. Our results show that capsaicin reduces HSC proliferation, migration, and expression of profibrogenic markers of activated and primary mouse HSCs. In conclusion, the present study shows that capsaicin modulates proliferation, migration, and activation of HSC in vitro. PMID:23955514

  10. Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

    SciTech Connect

    Kheradmand, Arash; Dezfoulian, Omid; Alirezaei, Masoud; Rasoulian, Bahram

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer Spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. Black-Right-Pointing-Pointer Numerous studies have documented the direct action of ghrelin in the modulation of apoptosis in different cell types. Black-Right-Pointing-Pointer Ghrelin may be considered as a modulator of spermatogenesis in normal adult rats. Black-Right-Pointing-Pointer Ghrelin may be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors. -- Abstract: Under normal condition in the most mammals, spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. The present study was designed to determine the effects of ghrelin treatment on in vivo quality and quantity expression of apoptosis and proliferation specific indices in rat testicular germ cells. Twenty eight adult normal rats were subdivided into equal control and treatment groups. Treatment group received 3 nmol of ghrelin as subcutaneous injection for 30 consecutive days or vehicle to the control animals. The rats from each group (n = 7) were killed on days 10 and 30 and their testes were taken for immunocytochemical evaluation and caspase-3 assay. Immunohistochemical analysis indicated that the accumulations of Bax and PCNA peptides are generally more prominent in spermatocytes and spermatogonia of both groups. Likewise, the mean percentage of immunoreactive spermatocytes against Bax increased (P < 0.01) in the ghrelin-treated group on day 10, while despite of 30% increment in the Bax level of spermatocytes in the treated rats on day 30, however, it was not statistically significant. During the experimental period, only a few spermatogonia represented Bax expression and the changes of Bax immunolabling cells were negligible upon ghrelin treatment. Likewise, there were immunostaining cells against Bcl-2 in each germ cell neither in the control nor in the treated animals. In fact

  11. Identification of Predictive Gene Markers for Multipotent Stromal Cell Proliferation.

    PubMed

    Bellayr, Ian H; Marklein, Ross A; Lo Surdo, Jessica L; Bauer, Steven R; Puri, Raj K

    2016-06-01

    Multipotent stromal cells (MSCs) are known for their distinctive ability to differentiate into different cell lineages, such as adipocytes, chondrocytes, and osteocytes. They can be isolated from numerous tissue sources, including bone marrow, adipose tissue, skeletal muscle, and others. Because of their differentiation potential and secretion of growth factors, MSCs are believed to have an inherent quality of regeneration and immune suppression. Cellular expansion is necessary to obtain sufficient numbers for use; however, MSCs exhibit a reduced capacity for proliferation and differentiation after several rounds of passaging. In this study, gene markers of MSC proliferation were identified and evaluated for their ability to predict proliferative quality. Microarray data of human bone marrow-derived MSCs were correlated with two proliferation assays. A collection of 24 genes were observed to significantly correlate with both proliferation assays (|r| >0.70) for eight MSC lines at multiple passages. These 24 identified genes were then confirmed using an additional set of MSCs from eight new donors using reverse transcription quantitative polymerase chain reaction (RT-qPCR). The proliferative potential of the second set of MSCs was measured for each donor/passage for confluency fraction, fraction of EdU+ cells, and population doubling time. The second set of MSCs exhibited a greater proliferative potential at passage 4 in comparison to passage 8, which was distinguishable by 15 genes; however, only seven of the genes (BIRC5, CCNA2, CDC20, CDK1, PBK, PLK1, and SPC25) demonstrated significant correlation with MSC proliferation regardless of passage. Our analyses revealed that correlation between gene expression and proliferation was consistently reduced with the inclusion of non-MSC cell lines; therefore, this set of seven genes may be more strongly associated with MSC proliferative quality. Our results pave the way to determine the quality of an MSC population for a

  12. Morphological and functional platelet abnormalities in Berkeley sickle cell mice.

    PubMed

    Shet, Arun S; Hoffmann, Thomas J; Jirouskova, Marketa; Janczak, Christin A; Stevens, Jacqueline R M; Adamson, Adewole; Mohandas, Narla; Manci, Elizabeth A; Cynober, Therese; Coller, Barry S

    2008-01-01

    Berkeley sickle cell mice are used as animal models of human sickle cell disease but there are no reports of platelet studies in this model. Since humans with sickle cell disease have platelet abnormalities, we studied platelet morphology and function in Berkeley mice (SS). We observed elevated mean platelet forward angle light scatter (FSC) values (an indirect measure of platelet volume) in SS compared to wild type (WT) (37+/-3.2 vs. 27+/-1.4, mean+/-SD; p<0.001), in association with moderate thrombocytopenia (505+/-49 x 10(3)/microl vs. 1151+/-162 x 10(3)/microl; p<0.001). Despite having marked splenomegaly, SS mice had elevated levels of Howell-Jolly bodies and "pocked" erythrocytes (p<0.001 for both) suggesting splenic dysfunction. SS mice also had elevated numbers of thiazole orange positive platelets (5+/-1% vs. 1+/-1%; p<0.001), normal to low plasma thrombopoietin levels, normal plasma glycocalicin levels, normal levels of platelet recovery, and near normal platelet life spans. Platelets from SS mice bound more fibrinogen and antibody to P-selectin following activation with a threshold concentration of a protease activated receptor (PAR)-4 peptide compared to WT mice. Enlarged platelets are associated with a predisposition to arterial thrombosis in humans and some humans with SCD have been reported to have large platelets. Thus, additional studies are needed to assess whether large platelets contribute either to pulmonary hypertension or the large vessel arterial occlusion that produces stroke in some children with sickle cell disease. PMID:18374611

  13. 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

  14. Poisson‐event‐based analysis of cell proliferation

    PubMed Central

    Wills, John W.; Brown, M. Rowan; Rees, Paul

    2015-01-01

    Abstract 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. © 2015 The Authors. Published by Wiley Periodicals, Inc. PMID:25572722

  15. 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

  16. Estimation of Cell Proliferation Dynamics Using CFSE Data

    PubMed Central

    Banks, H.T.; Sutton, Karyn L.; Thompson, W. Clayton; Bocharov, Gennady; Roose, Dirk; Schenkel, Tim; Meyerhans, Andreas

    2010-01-01

    Advances in fluorescent labeling of cells as measured by flow cytometry have allowed for quantitative studies of proliferating populations of cells. The investigations (Luzyanina et al. in J. Math. Biol. 54:57–89, 2007; J. Math. Biol., 2009; Theor. Biol. Med. Model. 4:1–26, 2007) contain a mathematical model with fluorescence intensity as a structure variable to describe the evolution in time of proliferating cells labeled by carboxyfluorescein succinimidyl ester (CFSE). Here, this model and several extensions/modifications are discussed. Suggestions for improvements are presented and analyzed with respect to statistical significance for better agreement between model solutions and experimental data. These investigations suggest that the new decay/label loss and time dependent effective proliferation and death rates do indeed provide improved fits of the model to data. Statistical models for the observed variability/noise in the data are discussed with implications for uncertainty quantification. The resulting new cell dynamics model should prove useful in proliferation assay tracking and modeling, with numerous applications in the biomedical sciences. PMID:20195910

  17. Inhibition of REST Suppresses Proliferation and Migration in Glioblastoma Cells

    PubMed Central

    Zhang, Dianbao; Li, Ying; Wang, Rui; Li, Yunna; Shi, Ping; Kan, Zhoumi; Pang, Xining

    2016-01-01

    Glioblastoma (GBM) is the most common primary brain tumor, with poor prognosis and a lack of effective therapeutic options. The aberrant expression of transcription factor REST (repressor element 1-silencing transcription factor) had been reported in different kinds of tumors. However, the function of REST and its mechanisms in GBM remain elusive. Here, REST expression was inhibited by siRNA silencing in U-87 and U-251 GBM cells. Then CCK-8 assay showed significantly decreased cell proliferation, and the inhibition of migration was verified by scratch wound healing assay and transwell assay. Using cell cycle analysis and Annexin V/PI straining assay, G1 phase cell cycle arrest was found to be a reason for the suppression of cell proliferation and migration upon REST silencing, while apoptosis was not affected by REST silencing. Further, the detection of REST-downstream genes involved in cytostasis and migration inhibition demonstrated that CCND1 and CCNE1 were reduced; CDK5R1, BBC3, EGR1, SLC25A4, PDCD7, MAPK11, MAPK12, FADD and DAXX were enhanced, among which BBC3 and DAXX were direct targets of REST, as verified by ChIP (chromatin immunoprecipitation) and Western blotting. These data suggested that REST is a master regulator that maintains GBM cells proliferation and migration, partly through regulating cell cycle by repressing downstream genes, which might represent a potential target for GBM therapy. PMID:27153061

  18. Inhibition of REST Suppresses Proliferation and Migration in Glioblastoma Cells.

    PubMed

    Zhang, Dianbao; Li, Ying; Wang, Rui; Li, Yunna; Shi, Ping; Kan, Zhoumi; Pang, Xining

    2016-01-01

    Glioblastoma (GBM) is the most common primary brain tumor, with poor prognosis and a lack of effective therapeutic options. The aberrant expression of transcription factor REST (repressor element 1-silencing transcription factor) had been reported in different kinds of tumors. However, the function of REST and its mechanisms in GBM remain elusive. Here, REST expression was inhibited by siRNA silencing in U-87 and U-251 GBM cells. Then CCK-8 assay showed significantly decreased cell proliferation, and the inhibition of migration was verified by scratch wound healing assay and transwell assay. Using cell cycle analysis and Annexin V/PI straining assay, G1 phase cell cycle arrest was found to be a reason for the suppression of cell proliferation and migration upon REST silencing, while apoptosis was not affected by REST silencing. Further, the detection of REST-downstream genes involved in cytostasis and migration inhibition demonstrated that CCND1 and CCNE1 were reduced; CDK5R1, BBC3, EGR1, SLC25A4, PDCD7, MAPK11, MAPK12, FADD and DAXX were enhanced, among which BBC3 and DAXX were direct targets of REST, as verified by ChIP (chromatin immunoprecipitation) and Western blotting. These data suggested that REST is a master regulator that maintains GBM cells proliferation and migration, partly through regulating cell cycle by repressing downstream genes, which might represent a potential target for GBM therapy. PMID:27153061

  19. 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.

  20. Cytokine signaling for proliferation, survival, and death in hematopoietic cells.

    PubMed

    Miyajima, A; Ito, Y; Kinoshita, T

    1999-04-01

    The survival, proliferation, and differentiation of hematopoietic cells are regulated by cytokines. In the absence of cytokines, hematopoietic cells not only stop proliferation, but undergo apoptosis. This strict dependency of hematopoietic cells on cytokines is an important mechanism that maintains the homeostasis of blood cells. Cytokines induce various intracellular signaling pathways by activating the receptor-associated Janus kinases (Jaks), and distinct signals are responsible for cell cycle progression and cell survival. Induction of signals for cell cycle progression without suppressing apoptosis results in apoptotic cell death, indicating the essential role of anti-apoptotic signaling for cell growth. In hematopoietic cells, Ras, a cellular protooncogen product, and phosphatidylinositol 3 kinase are involved in the suppression of apoptosis. Cytokine depletion not only turns off anti-apoptotic signaling, but also actively induces cell death by activating caspases, a distinct family of cysteine proteases. Alterations in the mechanisms of cytokine signaling for cell cycle progression and anti-apoptotic function are implicated in hematological disorders. PMID:10222650

  1. [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. PMID:25597721

  2. Epithelial TRPV1 signaling accelerates gingival epithelial cell proliferation.

    PubMed

    Takahashi, N; Matsuda, Y; Yamada, H; Tabeta, K; Nakajima, T; Murakami, S; Yamazaki, K

    2014-11-01

    Transient receptor potential cation channel subfamily V member 1 (TRPV1), a member of the calcium-permeable thermosensitive transient receptor potential superfamily, is a sensor of thermal and chemical stimuli. TRPV1 is activated by noxious heat (> 43°C), acidic conditions (pH < 6.6), capsaicin, and endovanilloids. This pain receptor was discovered on nociceptive fibers in the peripheral nervous system. TRPV1 was recently found to be expressed by non-neuronal cells, such as epithelial cells. The oral gingival epithelium is exposed to multiple noxious stimuli, including heat and acids derived from endogenous and exogenous substances; however, whether gingival epithelial cells (GECs) express TRPV1 is unknown. We show that both TRPV1 mRNA and protein are expressed by GECs. Capsaicin, a TRPV1 agonist, elevated intracellular Ca(2+) levels in the gingival epithelial cell line, epi 4. Moreover, TRPV1 activation in epi 4 cells accelerated proliferation. These responses to capsaicin were inhibited by a specific TRPV1 antagonist, SB-366791. We also observed GEC proliferation in capsaicin-treated mice in vivo. No effects were observed on GEC apoptosis by epithelial TRPV1 signaling. To examine the molecular mechanisms underlying this proliferative effect, we performed complementary (c)DNA microarray analysis of capsaicin-stimulated epi 4 cells. Compared with control conditions, 227 genes were up-regulated and 232 genes were down-regulated following capsaicin stimulation. Several proliferation-related genes were validated by independent experiments. Among them, fibroblast growth factor-17 and neuregulin 2 were significantly up-regulated in capsaicin-treated epi 4 cells. Our results suggest that functional TRPV1 is expressed by GECs and contributes to the regulation of cell proliferation. PMID:25266715

  3. 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.

  4. Effect of interleukins on the proliferation and survival of B cell chronic lymphocytic leukaemia cells.

    PubMed Central

    Mainou-Fowler, T; Copplestone, J A; Prentice, A G

    1995-01-01

    AIMS--To investigate the effects of interleukin (IL) 1, 2, 4, and 5 on the proliferation and survival of peripheral blood B cells from patients with B chronic lymphocytic leukaemia (B-CLL) and compare them with the effects on normal peripheral blood B cells. METHODS--The proliferation and survival of pokeweed mitogen (PWM) activated B cells from B-CLL (n = 12) and normal peripheral blood (n = 5) were studied in vitro in response to IL-1, IL-2 IL-4, and IL-5. Survival of cells in cultures with or without added interleukins was studied by microscopic examination of cells and DNA agarose gel electrophoresis. RESULTS--Proliferation was observed in both B-CLL and normal peripheral blood cells on culture with IL-2 alone and also in some, but not all, B-CLL and normal peripheral blood cells with IL-1 and IL-4. However, there was greater variability in B-CLL cell responses than in normal peripheral blood cells. Il-5 did not affect normal peripheral blood cell proliferation but it increased proliferation in two B-CLL cases. Synergistic effects of these cytokines were not detected. IL-4 inhibited normal peripheral blood and B-CLL cell proliferation after the addition of IL-2. Inhibition of B-CLL cell responses to IL-2 was also observed with IL-5 and Il-1. Survival of B-CLL cells in cultures was enhanced with IL-4 not by an increase in proliferation but by reduced apoptosis. No such effect was seen in normal peripheral blood cells. IL-2 had a less noticeable antiapoptotic effect; IL-5 enhanced apoptosis in B-CLL cells. CONCLUSIONS--B-CLL and normal peripheral blood cells proliferated equally well in response to IL-2. IL-4 had a much lower effect on B-CLL cell proliferation, but had noticeable antiapoptotic activity. IL-5 enhanced cell death by apoptosis. Images PMID:7629299

  5. 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

  6. Zearalenone exposure affects mouse oocyte meiotic maturation and granulosa cell proliferation.

    PubMed

    Hou, Yan-Jun; Zhu, Cheng-Cheng; Xu, Yin-Xue; Cui, Xiang-Shun; Kim, Nam-Hyung; Sun, Shao-Chen

    2015-09-01

    Zearalenone (ZEN) is a metabolite of Fusarium and is a common contaminant of grains and foodstuffs. ZEN acts as a xenoestrogen and is considered to be cytotoxic, tissue toxic, and genotoxic, which causes abortions and stillbirths in humans and animals. Since estrogens affect oocyte maturation during meiosis, in this study we investigated the effects of ZEN on mouse oocyte meiotic maturation and granulosa cell proliferation. Our results showed that ZEN-treated oocyte maturation rates were decreased, which might be due to the disrupted cytoskeletons: (1) ZEN treatment resulted in significantly more oocytes with abnormal spindle morphologies; (2) actin filament expression and distribution were also disrupted after ZEN treatment, which was confirmed by the aberrant distribution of actin regulatory proteins. In addition, cortical granule-free domains (CGFDs) were disrupted after ZEN treatment, which indicated that ZEN may affect mouse oocyte fertilization capability. ZEN reduced mouse granulosa cell proliferation in a dose-dependent manner as determined by MTT assay and TUNEL apoptosis analysis, which may be another cause for the decreased oocyte maturation. Thus, our results demonstrated that exposure to zearalenone affected oocyte meiotic maturation and granulosa cell proliferation in mouse. PMID:24733567

  7. Claudin-18 inhibits cell proliferation and motility mediated by inhibition of phosphorylation of PDK1 and Akt in human lung adenocarcinoma A549 cells.

    PubMed

    Shimobaba, Shun; Taga, Saeko; Akizuki, Risa; Hichino, Asami; Endo, Satoshi; Matsunaga, Toshiyuki; Watanabe, Ryo; Yamaguchi, Masahiko; Yamazaki, Yasuhiro; Sugatani, Junko; Ikari, Akira

    2016-06-01

    Abnormal expression of claudin subtypes has been reported in various cancers. However, the pathological role of each claudin has not been clarified in detail. Claudin-18 was absent in human non-small cell and small cell lung cancers, although it is expressed in normal lung tissues. Here, we examined the effect of claudin-18 expression on the expression of junctional proteins, cell proliferation, and cell motility using human lung adenocarcinoma A549 cells. Real-time PCR and western blotting showed that exogenous expression of claudin-18 had no effect on the expression of junctional proteins including claudin-1, zonula occludens-1 (ZO-1), occludin, and E-cadherin. Claudin-18 was mainly distributed in cell-cell contact areas concomitant with ZO-1. Cell proliferation was significantly decreased at 48 and 72h after seeding of claudin 18-expressing cells. Claudin-18 suppressed cell motility, whereas it increased cell death in anoikis. Claudin-18 decreased phosphorylated (p)-3-phosphoinositide-dependent protein kinase-1 (PDK1) and p-Akt levels without affecting p-epidermal growth factor receptor and p-phosphatidylinositol-3 kinase (PI3K) levels. Furthermore, claudin-18 was bound with PDK1 and suppressed the nuclear localization of PDK1. We suggest that claudin-18 suppresses the abnormal proliferation and motility of lung epithelial cells mediated by inhibition of the PI3K/PDK1/Akt signaling pathway. PMID:26919807

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

    PubMed

    Feng, Xiaoqi; Dickinson, Hugh G

    2010-07-01

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

  9. 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. PMID:23123964

  10. Modulation of insulin degrading enzyme activity and liver cell proliferation

    PubMed Central

    Pivovarova, Olga; von Loeffelholz, Christian; Ilkavets, Iryna; Sticht, Carsten; Zhuk, Sergei; Murahovschi, Veronica; Lukowski, Sonja; Döcke, Stephanie; Kriebel, Jennifer; de las Heras Gala, Tonia; Malashicheva, Anna; Kostareva, Anna; Lock, Johan F; Stockmann, Martin; Grallert, Harald; Gretz, Norbert; Dooley, Steven; Pfeiffer, Andreas FH; Rudovich, Natalia

    2015-01-01

    Diabetes mellitus type 2 (T2DM), insulin therapy, and hyperinsulinemia are independent risk factors of liver cancer. Recently, the use of a novel inhibitor of insulin degrading enzyme (IDE) was proposed as a new therapeutic strategy in T2DM. However, IDE inhibition might stimulate liver cell proliferation via increased intracellular insulin concentration. The aim of this study was to characterize effects of inhibition of IDE activity in HepG2 hepatoma cells and to analyze liver specific expression of IDE in subjects with T2DM. HepG2 cells were treated with 10 nM insulin for 24 h with or without inhibition of IDE activity using IDE RNAi, and cell transcriptome and proliferation rate were analyzed. Human liver samples (n = 22) were used for the gene expression profiling by microarrays. In HepG2 cells, IDE knockdown changed expression of genes involved in cell cycle and apoptosis pathways. Proliferation rate was lower in IDE knockdown cells than in controls. Microarray analysis revealed the decrease of hepatic IDE expression in subjects with T2DM accompanied by the downregulation of the p53-dependent genes FAS and CCNG2, but not by the upregulation of proliferation markers MKI67, MCM2 and PCNA. Similar results were found in the liver microarray dataset from GEO Profiles database. In conclusion, IDE expression is decreased in liver of subjects with T2DM which is accompanied by the dysregulation of p53 pathway. Prolonged use of IDE inhibitors for T2DM treatment should be carefully tested in animal studies regarding its potential effect on hepatic tumorigenesis. PMID:25945652

  11. Roles of Nrf2 in cell proliferation and differentiation.

    PubMed

    Murakami, Shohei; Motohashi, Hozumi

    2015-11-01

    The Keap1-Nrf2 system plays pivotal roles in defense mechanisms by regulating cellular redox homeostasis. Nrf2 is an inducible transcription factor that activates a battery of genes encoding antioxidant proteins and phase II enzymes in response to oxidative stress and electrophilic xenobiotics. The activity of Nrf2 is regulated by Keap1, which promotes the ubiquitination and subsequent degradation of Nrf2 under normal conditions and releases the inhibited Nrf2 activity upon exposure to the stresses. Though an impressive contribution of the Keap1-Nrf2 system to the protection from exogenous and endogenous electrophilic insults has been well established, a line of evidence has suggested that the Keap1-Nrf2 system has various novel functions, particularly in cell proliferation and differentiation. Because the proliferation and differentiation of diverse cell types are often influenced and modulated by the cellular redox balance, Nrf2 has been considered to control these cellular processes by regulating the cellular levels of reactive oxygen species (ROS). In addition, analyses of the genome-wide distribution of Nrf2 have identified new sets of Nrf2 target genes whose products are involved in cell proliferation and differentiation but not necessarily in the regulation of oxidative stress. Considering the most characteristic features of Nrf2 as an inducible transcription factor, a newly emerged concept proposes that the Keap1-Nrf2 system translates environmental stresses into regulatory network signals in cell fate determination. In this review, we introduce the contribution of Nrf2 to lineage-specific differentiation, maintenance and differentiation of stem cells, and proliferation of normal and cancer cells, and we discuss how the response to fluctuating environments modulates cell behavior through the Keap1-Nrf2 system. PMID:26119783

  12. 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. PMID:20809708

  13. 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. PMID:26013297

  14. Raman Spectroscopy of DNA Packaging in Individual Human Sperm Cells distinguishes Normal from Abnormal Cells

    SciTech Connect

    Huser, T; Orme, C; Hollars, C; Corzett, M; Balhorn, R

    2009-03-09

    Healthy human males produce sperm cells of which about 25-40% have abnormal head shapes. Increases in the percentage of sperm exhibiting aberrant sperm head morphologies have been correlated with male infertility, and biochemical studies of pooled sperm have suggested that sperm with abnormal shape may contain DNA that has not been properly repackaged by protamine during spermatid development. We have used micro-Raman spectroscopy to obtain Raman spectra from individual human sperm cells and examined how differences in the Raman spectra of sperm chromatin correlate with cell shape. We show that Raman spectra of individual sperm cells contain vibrational marker modes that can be used to assess the efficiency of DNA-packaging for each cell. Raman spectra obtained from sperm cells with normal shape provide evidence that DNA in these sperm is very efficiently packaged. We find, however, that the relative protein content per cell and DNA packaging efficiencies are distributed over a relatively wide range for sperm cells with both normal and abnormal shape. These findings indicate that single cell Raman spectroscopy should be a valuable tool in assessing the quality of sperm cells for in-vitro fertilization.

  15. 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

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

    PubMed

    Kang, Hye-Ryun; Lee, Yong-An; 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

  17. 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

  18. Hydroxyflavanone inhibits gastric carcinoma MGC-803 cell proliferation

    PubMed Central

    Zhang, Haiyan; Zhan, Zhuo; Cui, Mingfu; Gao, Yongjian; Wang, Dayu; Feng, Ye

    2015-01-01

    Gastric carcinoma (GC) is the most common primary malignancy of the digestive tract, with increasing incidence in many countries. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess inhibition of HepG2 cell proliferation by 2’-hydroxyflavanone. The STAT3 pathway was performed. 2’-hydroxyflavanone reduced inhibitory effects on MGC-803 cell proliferation. 2’-hydroxyflavanone exhibited the highest inhibition rate. Treatment of MGC-803 cells with 400, 200, and 100 μg/ml 2’-hydroxyflavanone resulted in 88.9±0.7%, 81.2±0.5%, 68.4±0.5% decrease in cell viability, respectively, indicating an IC50 of 9.3 μg/ml. The 100 μg/ml 2’-hydroxyflavanone can significantly inhibit the STAT3 pathway activation. 2’-hydroxyflavanone inhibits MGC-803 cell proliferation by inhibiting STAT3 pathway activation. This extract is therefore a potential drug candidate for treatment of liver cancer. PMID:26629250

  19. Ubiquitylation of CD98 limits cell proliferation and clonal expansion.

    PubMed

    Ablack, Jailal N G; Metz, Patrick J; Chang, John T; Cantor, Joseph M; Ginsberg, Mark H

    2015-12-01

    CD98 heavy chain (SLC3A2) facilitates lymphocyte clonal expansion that enables adaptive immunity; however, increased expression of CD98 is also a feature of both lymphomas and leukemias and represents a potential therapeutic target in these diseases. CD98 is transcriptionally regulated and ectopic expression of the membrane-associated RING-CH (MARCH) E3 ubiquitin ligases MARCH1 or MARCH8 leads to ubiquitylation and lysosomal degradation of CD98. Here, we examined the potential role of ubiquitylation in regulating CD98 expression and cell proliferation. We report that blocking ubiquitylation by use of a catalytically inactive MARCH or by creating a ubiquitylation-resistant CD98 mutant, prevents MARCH-induced CD98 downregulation in HeLa cells. March1-null T cells display increased CD98 expression. Similarly, T cells expressing ubiquitylation-resistant CD98 manifest increased proliferation in vitro and clonal expansion in vivo. Thus, ubiquitylation and the resulting downregulation of CD98 can limit cell proliferation and clonal expansion. PMID:26493331

  20. Proliferation of Schwann cells induced by axolemmal and myelin membranes

    SciTech Connect

    Dinneen, M..

    1985-01-01

    Purified Schwann Cells were cultured from neonatal rat sciatic nerve using a modification of the method of Brockes. Schwann cells and contaminating fibroblasts were unambiguously identified using fluorescent antibodies of 2'3' cyclic nucleotide 3'-phosphodiesterase and the thy 1.1 antigen respectively. The Schwann cells were quiescent unless challenged with mitogens. They proliferated rapidly in response to the soluble mitogen, cholera toxin, or to membrane fractions from rat CNS or PNS, prepared by the method of DeVries. Mitogenic activity was present in both axolemmal and myelin enriched fractions and promoted a 10-15 fold increase in the rate of /sup 3/H-thymidine uptake. The axolemmal mitogen was sensitive to heat (80/sup 0/C for 10 minutes), trypsin digestion (0.05% x 30 mins) or to treatment with endoglycosidase D, suggesting that it could be a glycoprotein. Fifty percent of the axolemmal mitogenic activity was solubilized in 1% octyl-glucoside. The solubilized material, however, was very unstable and further purification was not possible. The myelin associated mitogenic activity was markedly different. It was resistant to freeze thaw cycles, trypsin digestion of endoglycosidase treatment and the activity was actually enhanced by heating at 100/sup 0/C for two hours. It is proposed that the axolemmal activity is responsible for Schwann cell proliferation during development and that the myelin associated activity promotes Schwann cell proliferation during Wallerian degeneration.

  1. Extracellular potassium concentration regulates proliferation of immature cerebellar granule cells.

    PubMed

    Borodinsky, L N; Fiszman, M L

    1998-04-17

    The present study examines the effect of depolarizing potassium concentrations on the proliferation of immature rat cerebellar neurons. Cells inoculated in serum free medium and 5 mM KCl (5 K) showed a high degree of 3H-thymidine incorporation that decreased 24-48 h after plating as differentiation began. During the first 24 h after inoculation, cells grown in high potassium (25 K), showed a 34 +/- 3% increase (mean +/- S.E.M., n = 12) in 3H-thymidine incorporation as compared with the values observed in 5 K. After 24 h in vitro, cells grown in 25 K showed 23 +/- 3% (mean +/- S.E.M., n = 3) less DNA synthesis than those inoculated in 5 K. The increase in DNA synthesis due to 25 K was blocked by MgCl2 and nifedipine, but not by omega-conotoxin GVIA, suggesting that it is mediated by a Ca2+ influx via voltage-gated calcium channels (VGCC) of the L-subtype. High potassium-induced cell proliferation was blocked by the mitogen-activated protein kinase kinase (MEK1) inhibitor (PD98059, 75 microM). The number of neurons counted after 48 h in vitro in 25 K was 35-100% above of the number obtained with 5 K and this increase also was blocked by MgCl2 and nifedipine. These data support the hypothesis that depolarizing activity during neurogenesis plays a role in the modulation of cerebellar granule cells proliferation. PMID:9602050

  2. The interplay between invasion and proliferation in tumor cell navigation

    NASA Astrophysics Data System (ADS)

    Ben-Jacob, Eshel

    2013-03-01

    Tumor cells can employ different cellular and molecular modes of invasion. The two main phenotypic mechanisms are: 1. Amoeboid (or ``path finder'') cells that can squeeze through small gaps in the ECM (extracellular matrix). 2. Mesenchymal (or ``path generator'') cells that are more rigid and can decompose the ECM to pass through. In addition there is interplay between energy directed to more rapid motility vs. energy used for proliferation. Understanding the relative contributions of these distinct mechanisms and the balance between motility and proliferation to the efficiency of metastatic cancer migration is fundamental to the therapeutic targeting of cancer. We present a conceptual and modeling framework for the analysis and assessment of the success rate, time-to-target, and survival probability of amoeboid vs. mesenchymal modes. Similarly, we contrast invasion with and without proliferation. We treat the complex ECM geometry as a maze and employ semi-realistic modeling of cell motility. Our approach includes metabolic and timing degrees of freedom. The theoretical studies were compared with experimental efforts of cell navigation in specially designed microfluidic devices. Center for Theoretical Biological Physics sponsored by the NSF (Grant PHY-0822283) Rice University, The Tauber Family Foundation and the Maguy-Glass Chair in Physics of Complex Systems at Tel Aviv University.

  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. Tussilagone suppresses colon cancer cell proliferation by promoting the degradation of β-catenin

    SciTech Connect

    Li, Hua; Lee, Hwa Jin; Ahn, Yeon Hwa; Kwon, Hye Jin; Jang, Chang-Young; Kim, Woo-Young; Ryu, Jae-Ha

    2014-01-03

    Highlights: •Tussilagone (TSL) was purified from plant as an inhibitor of Wnt/β-catenin pathway. •TSL suppressed the β-catenin/T-cell factor transcriptional activity. •The proteasomal degradation of β-catenin was induced by TSL. •TSL suppressed the Wnt/β-catenin target genes, cyclin D1 and c-myc. •TSL inhibit the proliferation of colon cancer cells. -- Abstract: Abnormal activation of the Wnt/β-catenin signaling pathway frequently induces colon cancer progression. In the present study, we identified tussilagone (TSL), a compound isolated from the flower buds of Tussilago farfara, as an inhibitor on β-catenin dependent Wnt pathway. TSL suppressed β-catenin/T-cell factor transcriptional activity and down-regulated β-catenin level both in cytoplasm and nuclei of HEK293 reporter cells when they were stimulated by Wnt3a or activated by an inhibitor of glycogen synthase kinase-3β. Since the mRNA level was not changed by TSL, proteasomal degradation might be responsible for the decreased level of β-catenin. In SW480 and HCT116 colon cancer cell lines, TSL suppressed the β-catenin activity and also decreased the expression of cyclin D1 and c-myc, representative target genes of the Wnt/β-catenin signaling pathway, and consequently inhibited the proliferation of colon cancer cells. Taken together, TSL might be a potential chemotherapeutic agent for the prevention and treatment of human colon cancer.

  5. Role of interleukin in human natural killer cell proliferation

    SciTech Connect

    London, L.; Perussia, B.; Trinchieri, G.

    1986-03-01

    Human NK cells, defined by the antibody B73.1, can be induced to proliferate in vitro in the presence of an IL-2 containing conditioned medium (CM) and an irradiated lymphoblastoid line, Daudi. Proliferating NK cells maintain phenotypic and functional characteristics of resting NK cells while newly expressing surface activation antigens (HLA-DR, transferrin receptor, and IL-2 receptor recognized by anti-TAC antibody). A goat anti-IL-2 antiserum and the anti-TAC monoclonal antibody completely block /sup 3/H-TdR incorporation in NK cells stimulated with CM alone or with irradiated Daudi cells. Inhibition is also observed when the antibodies are added up to day 4 of culture, indicating that IL-2 is required for both initiation and maintenance of proliferation. Human recombinant IL-2, either alone or with irradiated lymphoblastoid cells, replaces the CM in initiating /sup 3/H-TdR incorporation. In limiting dilution analysis the frequency of B73.1 (+) cells responding to rIL-2 is approximately 1/2000 and it is increased ten to thirty fold with the addition of irradiated Daudi cells to the cultures. Cultures stimulated with rIL-2 in the presence of colchicine, show a significant proportion of B73.1 + cells entering cycle each day during the first 3 days. These data show that a significant proportion of resting NK cells are capable of responding to IL-2 and that this response can occur over a period of several days after initiation of cultures.

  6. Maduramicin Inhibits Proliferation and Induces Apoptosis in Myoblast Cells

    PubMed Central

    Chen, Xin; Gu, Ying; Singh, Karnika; Shang, Chaowei; Barzegar, Mansoureh; Jiang, Shanxiang; Huang, Shile

    2014-01-01

    Maduramicin, a polyether ionophore antibiotic derived from the bacterium Actinomadura yumaensis, is currently used as a feed additive against coccidiosis in poultry worldwide. It has been clinically observed that maduramicin can cause skeletal muscle and heart cell damage, resulting in skeletal muscle degeneration, heart failure, and even death in animals and humans, if improperly used. However, the mechanism of its toxic action in myoblasts is not well understood. Using mouse myoblasts (C2C12) and human rhabdomyosarcoma (RD and Rh30) cells as an experimental model for myoblasts, here we found that maduramicin inhibited cell proliferation and induced cell death in a concentration-dependent manner. Further studies revealed that maduramicin induced accumulation of the cells at G0/G1 phase of the cell cycle, and induced apoptosis in the cells. Concurrently, maduramicin downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and CDC25A, and upregulated expression of the CDK inhibitors (p21Cip1 and p27Kip1), resulting in decreased phosphorylation of Rb. Maduramicin also induced expression of BAK, BAD, DR4, TRADD and TRAIL, leading to activation of caspases 8, 9 and 3 as well as cleavage of poly ADP ribose polymerase (PARP). Taken together, our results suggest that maduramicin executes its toxicity in myoblasts at least by inhibiting cell proliferation and inducing apoptotic cell death. PMID:25531367

  7. 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. PMID:17096346

  8. Maduramicin inhibits proliferation and induces apoptosis in myoblast cells.

    PubMed

    Chen, Xin; Gu, Ying; Singh, Karnika; Shang, Chaowei; Barzegar, Mansoureh; Jiang, Shanxiang; Huang, Shile

    2014-01-01

    Maduramicin, a polyether ionophore antibiotic derived from the bacterium Actinomadura yumaensis, is currently used as a feed additive against coccidiosis in poultry worldwide. It has been clinically observed that maduramicin can cause skeletal muscle and heart cell damage, resulting in skeletal muscle degeneration, heart failure, and even death in animals and humans, if improperly used. However, the mechanism of its toxic action in myoblasts is not well understood. Using mouse myoblasts (C2C12) and human rhabdomyosarcoma (RD and Rh30) cells as an experimental model for myoblasts, here we found that maduramicin inhibited cell proliferation and induced cell death in a concentration-dependent manner. Further studies revealed that maduramicin induced accumulation of the cells at G0/G1 phase of the cell cycle, and induced apoptosis in the cells. Concurrently, maduramicin downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and CDC25A, and upregulated expression of the CDK inhibitors (p21Cip1 and p27Kip1), resulting in decreased phosphorylation of Rb. Maduramicin also induced expression of BAK, BAD, DR4, TRADD and TRAIL, leading to activation of caspases 8, 9 and 3 as well as cleavage of poly ADP ribose polymerase (PARP). Taken together, our results suggest that maduramicin executes its toxicity in myoblasts at least by inhibiting cell proliferation and inducing apoptotic cell death. PMID:25531367

  9. Arsenic promotes centrosome abnormalities and cell colony formation in p53 compromised human lung cells

    SciTech Connect

    Liao Weiting; Lin Pinpin; Cheng, T.-S.; Yu, H.-S.; Chang, Louis W.

    2007-12-01

    Epidemiological evidence indicated that residents, especially cigarette smokers, in arseniasis areas had significantly higher lung cancer risk than those living in non-arseniasis areas. Thus, an interaction between arsenic and cigarette smoking in lung carcinogenesis was suspected. p53 dysfunction or mutation in lung epithelial cells was frequently observed in cigarette smokers. Our present study was to explore the differential effects by arsenic on H1355 cells (human lung adenocarcinoma cell line with mutation in p53), BEAS-2B (immortalized lung epithelial cell with functional p53) and pifithrin-{alpha}-treated BEAS-2B cells (p53-inhibited cells). These cells were treated with different doses of sodium arsenite (0, 0.1, 1, 5 and 10 {mu}M) for 48 h. A greater reduction in cell viability was observed in the BEAS-2B cells vs. p53 compromised cells (H1355 or p53-inhibited BEAS-2B). Similar observation was also made on 7-day cell survival (growth) study. TUNEL analysis confirmed that there was indeed a significantly reduced arsenite-induced apoptosis found in p53-compromised cells. Centrosomal abnormality has been attributed to eventual chromosomal missegregation, aneuploidy and tumorigenesis. In our present study, reduced p21 and Gadd45a expressions and increased centrosomal abnormality (atopic and multiple centrosomes) were observed in both arsenite-treated H1355 and p53-inhibited BEAS-2B cells as compared with similarly treated BEAS-2B cells. Increased anchorage-independent growth (colony formation) of BEAS-2B cells co-treated with pifithrin-{alpha} and 5 {mu}M sodium arsenite was also observed in soft agar. Our present investigation demonstrated that arsenic would act specifically on p53 compromised cells (either with p53 dysfunction or inhibited) to induce centrosomal abnormality and colony formation. These findings provided strong evidence on the carcinogenic promotional role of arsenic, especially under the condition of p53 dysfunction.

  10. Voltage-Gated Ion Channels in Cancer Cell Proliferation

    PubMed Central

    Rao, Vidhya R.; Perez-Neut, Mathew; Kaja, Simon; Gentile, Saverio

    2015-01-01

    Changes of the electrical charges across the surface cell membrane are absolutely necessary to maintain cellular homeostasis in physiological as well as in pathological conditions. The opening of ion channels alter the charge distribution across the surface membrane as they allow the diffusion of ions such as K+, Ca++, Cl−, Na+. Traditionally, voltage-gated ion channels (VGIC) are known to play fundamental roles in controlling rapid bioelectrical signaling including action potential and/or contraction. However, several investigations have revealed that these classes of proteins can also contribute significantly to cell mitotic biochemical signaling, cell cycle progression, as well as cell volume regulation. All these functions are critically important for cancer cell proliferation. Interestingly, a variety of distinct VGICs are expressed in different cancer cell types, including metastasis but not in the tissues from which these tumors were generated. Given the increasing evidence suggesting that VGIC play a major role in cancer cell biology, in this review we discuss the role of distinct VGIC in cancer cell proliferation and possible therapeutic potential of VIGC pharmacological manipulation. PMID:26010603

  11. Tracking Immune Cell Proliferation and Cytotoxic Potential Using Flow Cytometry

    PubMed Central

    Tario, Joseph D.; Muirhead, Katharine A.; Pan, Dalin; Munson, Mark E.; Wallace, Paul K.

    2015-01-01

    In the second edition of this series, we described the use of cell tracking dyes in combination with tetramer reagents and traditional phenotyping protocols to monitor levels of proliferation and cytokine production in antigen-specific CD8+ T cells. In particular, we illustrated how tracking dye fluorescence profiles could be used to ascertain the precursor frequencies of different subsets in the T-cell pool that are able to bind tetramer, synthesize cytokines, undergo antigen-driven proliferation, and/or carry out various combinations of these functional responses. Analysis of antigen-specific proliferative responses represents just one of many functions that can be monitored using cell tracking dyes and flow cytometry. In this third edition, we address issues to be considered when combining two different tracking dyes with other phenotypic and viability probes for the assessment of cytotoxic effector activity and regulatory T-cell functions. We summarize key characteristics of and differences between general protein- and membrane-labeling dyes, discuss determination of optimal staining concentrations, and provide detailed labeling protocols for both dye types. Examples of the advantages of two-color cell tracking are provided in the form of protocols for (a) independent enumeration of viable effector and target cells in a direct cytotoxicity assay and (b) simultaneous monitoring of proliferative responses in effector and regulatory T cells. PMID:21116982

  12. Effects of distal cholesterol biosynthesis inhibitors on cell proliferation and cell cycle progression.

    PubMed

    Fernández, Carlos; Martín, Miguel; Gómez-Coronado, Diego; Lasunción, Miguel A

    2005-05-01

    Cholesterol is a major lipid component of the plasma membrane in animal cells. In addition to its structural requirement, cholesterol is essential in cell proliferation and other cell processes. The aim of the present study was to elucidate the stringency of the requirement for cholesterol as a regulator of proliferation and cell cycle progression, compared with other sterols of the cholesterol biosynthesis pathway. Human promyelocytic HL-60 cells were cultured in cholesterol-free medium and treated with different distal inhibitors of cholesterol biosynthesis (zaragozic acid, SKF 104976, SR 31747, BM 15766, and AY 9944), which allow the synthesis of isoprenoid derivatives and different sets of sterol intermediates, but not cholesterol. The results showed that only the inhibition of sterol Delta7-reductase was compatible with cell proliferation. Blocking cholesterol biosynthesis upstream of this enzyme resulted in the inhibition of cell proliferation and cell cycle arrest selectively in G2/M phase. PMID:15687348

  13. Fenofibrate, a peroxisome proliferator-activated receptor α ligand, prevents abnormal liver function induced by a fasting–refeeding process

    SciTech Connect

    Lee, Joon No; Dutta, Raghbendra Kumar; Kim, Seul-Gi; Lim, Jae-Young; Kim, Se-Jin; Choe, Seong-Kyu; Yoo, Kyeong-Won; Song, Seung Ryel; Park, Do-Sim; So, Hong-Seob; Park, Raekil

    2013-12-06

    Highlights: •A fasting–refeeding high fat diet (HDF) model mimics irregular eating habit. •A fasting–refeeding HFD induces liver ballooning injury. •A fasting–refeeding HDF process elicits hepatic triglyceride accumulation. •Fenofibrate, PPARα ligand, prevents liver damage induced by refeeding HFD. -- Abstract: Fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, is an anti-hyperlipidemic agent that has been widely used in the treatment of dyslipidemia. In this study, we examined the effect of fenofibrate on liver damage caused by refeeding a high-fat diet (HFD) in mice after 24 h fasting. Here, we showed that refeeding HFD after fasting causes liver damage in mice determined by liver morphology and liver cell death. A detailed analysis revealed that hepatic lipid droplet formation is enhanced and triglyceride levels in liver are increased by refeeding HFD after starvation for 24 h. Also, NF-κB is activated and consequently induces the expression of TNF-α, IL1-β, COX-2, and NOS2. However, treating with fenofibrate attenuates the liver damage and triglyceride accumulation caused by the fasting–refeeding HFD process. Fenofibrate reduces the expression of NF-κB target genes but induces genes for peroxisomal fatty acid oxidation, peroxisome biogenesis and mitochondrial fatty acid oxidation. These results strongly suggest that the treatment of fenofibrate ameliorates the liver damage induced by fasting–refeeding HFD, possibly through the activation of fatty acid oxidation.

  14. Cholinergic receptor pathways involved in apoptosis, cell proliferation and neuronal differentiation

    PubMed Central

    Resende, Rodrigo R; Adhikari, Avishek

    2009-01-01

    Acetylcholine (ACh) has been shown to modulate neuronal differentiation during early development. Both muscarinic and nicotinic acetylcholine receptors (AChRs) regulate a wide variety of physiological responses, including apoptosis, cellular proliferation and neuronal differentiation. However, the intracellular mechanisms underlying these effects of AChR signaling are not fully understood. It is known that activation of AChRs increase cellular proliferation and neurogenesis and that regulation of intracellular calcium through AChRs may underlie the many functions of ACh. Intriguingly, activation of diverse signaling molecules such as Ras-mitogen-activated protein kinase, phosphatidylinositol 3-kinase-Akt, protein kinase C and c-Src is modulated by AChRs. Here we discuss the roles of ACh in neuronal differentiation, cell proliferation and apoptosis. We also discuss the pathways involved in these processes, as well as the effects of novel endogenous AChRs agonists and strategies to enhance neuronal-differentiation of stem and neural progenitor cells. Further understanding of the intracellular mechanisms underlying AChR signaling may provide insights for novel therapeutic strategies, as abnormal AChR activity is present in many diseases. PMID:19712465

  15. Regulation of nuclear transport in proliferating and quiescent cells.

    PubMed

    Feldherr, C M; Akin, D

    1993-03-01

    Previously, we compared signal-mediated nuclear transport in proliferating and quiescent BALB/c 3T3 cells and found that both the relative rate of nuclear uptake and the functional size of the transport channels were significantly greater in proliferating cells. In this study, the possible causes of these permeability differences were investigated. To determine if the decrease in transport capacity in quiescent cells was due to a reduction in the availability of soluble cytoplasmic factors (i.e., ATP or receptors for nuclear location sequences), or changes in the properties of the pores themselves, proliferating and quiescent cells were fused, and nuclear import of nucleoplasmin-coated gold (NP-gold) particles was assayed in the heterokaryons 50-60 min later. Significant differences in nuclear uptake were maintained following fusion, even though the two nuclei shared a common cytoplasm, consistent with the view that permeability is regulated at the level of the pores. Cell shape also influenced signal-mediated nuclear import. This was demonstrated by studying transport in rounded and flattened cells attached to different-size palladium domains that were deposited on a nonadhesive substrate. Based on analysis of the nuclear uptake rates of large (110-270 A in diameter) and small (50-80 A in diameter) coated gold particles, it was determined that the functional size of the pores was significantly greater in flattened cells. The effect of growth factors on recovery of nuclear transport capacity following serum depletion was also analyzed. Partial recovery was achieved by treating cells with physiological concentrations of EGF, IGF-1, or PDGF; however, complete recovery required both EGF and IGF-1. PMID:8453991

  16. Proliferation of Multiple Cell Types in the Skeletal Muscle Tissue Elicited by Acute p21 Suppression

    PubMed Central

    Biferi, Maria Grazia; Nicoletti, Carmine; Falcone, Germana; Puggioni, Eleonora M R; Passaro, Nunzia; Mazzola, Alessia; Pajalunga, Deborah; Zaccagnini, Germana; Rizzuto, Emanuele; Auricchio, Alberto; Zentilin, Lorena; De Luca, Gabriele; Giacca, Mauro; Martelli, Fabio; Musio, Antonio; Musarò, Antonio; Crescenzi, Marco

    2015-01-01

    Although in the last decades the molecular underpinnings of the cell cycle have been unraveled, the acquired knowledge has been rarely translated into practical applications. Here, we investigate the feasibility and safety of triggering proliferation in vivo by temporary suppression of the cyclin-dependent kinase inhibitor, p21. Adeno-associated virus (AAV)-mediated, acute knockdown of p21 in intact skeletal muscles elicited proliferation of multiple, otherwise quiescent cell types, notably including satellite cells. Compared with controls, p21-suppressed muscles exhibited a striking two- to threefold expansion in cellularity and increased fiber numbers by 10 days post-transduction, with no detectable inflammation. These changes partially persisted for at least 60 days, indicating that the muscles had undergone lasting modifications. Furthermore, morphological hyperplasia was accompanied by 20% increases in maximum strength and resistance to fatigue. To assess the safety of transiently suppressing p21, cells subjected to p21 knockdown in vitro were analyzed for γ-H2AX accumulation, DNA fragmentation, cytogenetic abnormalities, ploidy, and mutations. Moreover, the differentiation competence of p21-suppressed myoblasts was investigated. These assays confirmed that transient suppression of p21 causes no genetic damage and does not impair differentiation. Our results establish the basis for further exploring the manipulation of the cell cycle as a strategy in regenerative medicine. PMID:25669433

  17. Anisomycin-induced GATA-6 degradation accompanying a decrease of proliferation of colorectal cancer cell.

    PubMed

    Ushijima, Hironori; Horyozaki, Akiko; Maeda, Masatomo

    2016-09-01

    Transcription factor GATA-6 plays a key role in normal cell differentiation of the mesoderm and endoderm. On the other hand, GATA-6 is abnormally overexpressed in many clinical gastrointestinal cancer tissue samples, and accelerates cell proliferation or an anti-apoptotic response in cancerous tissues. We previously showed that activation of the JNK signaling cascade causes proteolysis of GATA-6. In this study, we demonstrated that anisomycin, a JNK activator, stimulates nuclear export of GATA-6 in a colorectal cancer cell line, DLD-1. Concomitantly, anisomycin remarkably inhibits the proliferation of DLD-1 cells via G2/M arrest in a plate culture. However, it did not induce apoptosis under growth arrest conditions. Furthermore, the growth of DLD-1 cells in a spheroid culture was suppressed by anisomycin. Although 5-FU showed only a slight inhibitory effect on 3D spheroid cultures, the same concentration of 5-FU together with a low concentration of anisomycin exhibited strong growth inhibition. These results suggest that the induction of GATA-6 dysfunction may be more effective for chemotherapy for colorectal cancer, although the mechanism underlying the synergistic effect of 5-FU and anisomycin remains unknown. PMID:27404124

  18. Ionizing Irradiation Not Only Inactivates Clonogenic Potential in Primary Normal Human Diploid Lens Epithelial Cells but Also Stimulates Cell Proliferation in a Subset of This Population

    PubMed Central

    Fujimichi, Yuki; Hamada, Nobuyuki

    2014-01-01

    Over the past century, ionizing radiation has been known to induce cataracts in the crystalline lens of the eye, but its mechanistic underpinnings remain incompletely understood. This study is the first to report the clonogenic survival of irradiated primary normal human lens epithelial cells and stimulation of its proliferation. Here we used two primary normal human cell strains: HLEC1 lens epithelial cells and WI-38 lung fibroblasts. Both strains were diploid, and a replicative lifespan was shorter in HLEC1 cells. The colony formation assay demonstrated that the clonogenic survival of both strains decreases similarly with increasing doses of X-rays. A difference in the survival between two strains was actually insignificant, although HLEC1 cells had the lower plating efficiency. This indicates that the same dose inactivates the same fraction of clonogenic cells in both strains. Intriguingly, irradiation enlarged the size of clonogenic colonies arising from HLEC1 cells in marked contrast to those from WI-38 cells. Such enhanced proliferation of clonogenic HLEC1 cells was significant at ≥2 Gy, and manifested as increments of ≤2.6 population doublings besides sham-irradiated controls. These results suggest that irradiation of HLEC1 cells not only inactivates clonogenic potential but also stimulates proliferation of surviving uniactivated clonogenic cells. Given that the lens is a closed system, the stimulated proliferation of lens epithelial cells may not be a homeostatic mechanism to compensate for their cell loss, but rather should be regarded as abnormal. This is because these findings are consistent with the early in vivo evidence documenting that irradiation induces excessive proliferation of rabbit lens epithelial cells and that suppression of lens epithelial cell divisions inhibits radiation cataractogenesis in frogs and rats. Thus, our in vitro model will be useful to evaluate the excessive proliferation of primary normal human lens epithelial cells that

  19. 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.

  20. 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

  1. Requirements for dE2F function in proliferating cells and in post-mitotic differentiating cells.

    PubMed Central

    Brook, A; Xie, J E; Du, W; Dyson, N

    1996-01-01

    The transcription factor E2F is a target of the retinoblastoma tumor suppressor protein (pRB) and may mediate pRB regulation of S phase entry in mammalian cells. The recent identification of mutant alleles of the Drosophila E2F gene (dE2F) has shown that dE2F is required for embryogenesis. dE2F-mutant embryos lack a co-ordinated program of gene expression which accompanies S phase entry and DNA synthesis declines to levels that are barely detectable. We have investigated the role of the dE2F gene at later stages of development. dE2F is expressed in several larval tissues and is required for cell proliferation in the eye imaginal disc. Surprisingly, dE2F expression persists in post-mitotic cells of the eye disc of third-instar larvae. The loss of dE2F function in these cells causes a novel phenotype, characterized by loss of photoreceptors and abnormal rhabdomere cell morphology. These results show that dE2F is required at multiple stages of development and suggest that E2F may have an important function in post-mitotic cells in addition to its role during cell proliferation. Images PMID:8670871

  2. Endothelial cell proliferation associated with lesions of murine systemic candidiasis.

    PubMed Central

    Ashman, R B; Papadimitriou, J M

    1994-01-01

    Neovascularization is associated with tumor growth and some inflammatory diseases but has not been reported to be induced by infectious agents. In a mouse model of systemic Candida albicans infection, extensive endothelial cell proliferation was seen in the periphery of brain abscesses and in the areas of fungal pyelonephritis in the kidney. This finding is important for an understanding of the pathogenesis of fungal infections and may contribute to an analysis of the mechanisms of angiogenesis. Images PMID:7523305

  3. 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.

  4. Nanoscale Drug Delivery Platforms Overcome Platinum-Based Resistance in Cancer Cells Due to Abnormal Membrane Protein Trafficking

    PubMed Central

    Xue, Xue; Hall, Matthew D.; Zhang, Qiang; Wang, Paul C.; Gottesman, Michael M.; Liang, Xing-Jie

    2014-01-01

    The development of cellular resistance to platinum-based chemotherapies is often associated with reduced intracellular platinum concentrations. In some models, this reduction is due to abnormal membrane protein trafficking, resulting in reduced uptake by transporters at the cell surface. Given the central role of platinum drugs in the clinic, it is critical to overcome cisplatin resistance by bypassing the plasma membrane barrier to significantly increase the intracellular cisplatin concentration enough to inhibit the proliferation of cisplatin-resistant cells. Therefore, rational design of appropriate nanoscale drug delivery platforms (nDDPs) loaded with cisplatin or other platinum analogs as payloads is a possible strategy to solve this problem. This review will focus on the known mechanism of membrane trafficking in cisplatin-resistant cells, and the development and employment of nDDPs to improve cell uptake of cisplatin. PMID:24219825

  5. Rnd3 regulates lung cancer cell proliferation through notch signaling.

    PubMed

    Tang, Yongjun; Hu, Chengping; Yang, Huaping; Cao, Liming; Li, Yuanyuan; Deng, Pengbo; Huang, Li

    2014-01-01

    Rnd3/RhoE is a small Rho GTPase involved in the regulation of different cell behaviors. Dysregulation of Rnd3 has been linked to tumorigenesis and metastasis. Lung cancers are the leading cause of cancer-related death in the West and around the world. The expression of Rnd3 and its ectopic role in non-small cell lung cancer (NSCLC) remain to be explored. Here, we reported that Rnd3 was down-regulated in three NSCLC cell lines: H358, H520 and A549. The down-regulation of Rnd3 led to hyper-activation of Rho Kinase and Notch signaling. The reintroduction of Rnd3 or selective inhibition of Notch signaling, but not Rho Kinase signaling, blocked the proliferation of H358 and H520 cells. Mechanistically, Notch intracellular domain (NICD) protein abundance in H358 cells was regulated by Rnd3-mediated NICD proteasome degradation. Rnd3 regulated H358 and H520 cell proliferation through a Notch1/NICD/Hes1 signaling axis independent of Rho Kinase. PMID:25372032

  6. Rnd3 Regulates Lung Cancer Cell Proliferation through Notch Signaling

    PubMed Central

    Tang, Yongjun; Hu, Chengping; Yang, Huaping; Cao, Liming; Li, Yuanyuan; Deng, Pengbo; Huang, Li

    2014-01-01

    Rnd3/RhoE is a small Rho GTPase involved in the regulation of different cell behaviors. Dysregulation of Rnd3 has been linked to tumorigenesis and metastasis. Lung cancers are the leading cause of cancer-related death in the West and around the world. The expression of Rnd3 and its ectopic role in non-small cell lung cancer (NSCLC) remain to be explored. Here, we reported that Rnd3 was down-regulated in three NSCLC cell lines: H358, H520 and A549. The down-regulation of Rnd3 led to hyper-activation of Rho Kinase and Notch signaling. The reintroduction of Rnd3 or selective inhibition of Notch signaling, but not Rho Kinase signaling, blocked the proliferation of H358 and H520 cells. Mechanistically, Notch intracellular domain (NICD) protein abundance in H358 cells was regulated by Rnd3-mediated NICD proteasome degradation. Rnd3 regulated H358 and H520 cell proliferation through a Notch1/NICD/Hes1 signaling axis independent of Rho Kinase. PMID:25372032

  7. Wnt inhibitory factor-1 regulates glioblastoma cell cycle and proliferation.

    PubMed

    Wu, Jun; Fang, Jiasheng; Yang, Zhuanyi; Chen, Fenghua; Liu, Jingfang; Wang, Yanjin

    2012-10-01

    Wnt proteins are powerful regulators of cell proliferation and differentiation, and activation of the Wnt signalling pathway is involved in the pathogenesis of several types of human tumours. Wnt inhibitory factor-1 (WIF-1) acts as a Wnt antagonist and tumour suppressor. Previous studies have shown that reducing expression of the WIF-1 gene aberrantly activates Wnt signalling and induces the development of certain types of cancers. In the present study, we examined the expression of WIF-1 in human primary glioblastoma multiforme (GBM) tumours. Studies using semiquantitative reverse transcription-polymerase chain reaction and immunohistochemical analysis revealed that WIF-1 expression is lower in human GBM than in normal brain tissue. To clarify the role of WIF-1, we transfected U251 human glioblastoma-derived cells, which do not express WIF-1, with the pcDNA3.1-WIF1 vector to restore WIF-1 expression. The results of cell proliferation, colony formation and apoptosis assays, as well as flow cytometry, indicate that exogenous WIF-1 has no effect on U251 cell apoptosis, but does arrest cells at the G(0)/G(1) phase and inhibit cell growth. Collectively, our data suggest that WIF-1 is a potent inhibitor of GBM growth. PMID:22901505

  8. Cell proliferation in vitro modulates fibroblast collagenase activity

    SciTech Connect

    Lindblad, W.J.; Flood, L.

    1986-05-01

    Collagenase enzyme activity is regulated by numerous control mechanisms which prevent excessive release and activation of this protease. A primary mechanism for regulating enzyme extracellular activity may be linked to cell division, therefore they have examined the release of collagenase by fibroblasts in vitro in response to cellular proliferation. Studies were performed using fibroblasts derived from adult rat dermis maintained in DMEM containing 10% newborn calf serum, 25 mM tricine buffer, and antibiotics. Cells between subculture 10 and 19 were used with enzyme activity determined with a /sup 14/C-labelled soluble Type I collagen substrate with and without trypsin activation. Fibroblasts, trypsinized and plated at low density secreted 8.5 fold more enzyme than those cells at confluence (975 vs. 115 dpm/..mu..g DNA). This diminution occurred gradually as the cells went from logrithmic growth towards confluence. Confluent fibroblast monolayers were scraped in a grid arrangement, stimulating the remaining cells to divide, without exposure to trypsin. Within 24-48 hr postscraping enzyme levels had increased 260-400%, accompanied by enhanced incorporation of /sup 3/H-thymidine and /sup 3/H-uridine into cell macromolecules. The burst of enzyme release began to subside 12 hr later. These results support a close relationship between fibroblast proliferation and collagenase secretion.

  9. 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

  10. TBX2 blocks myogenesis and promotes proliferation in rhabdomyosarcoma cells

    PubMed Central

    Zhu, Bo; Zhang, Meiling; Byrum, Stephanie D.; Tackett, Alan J.; Davie, Judith K.

    2014-01-01

    Rhabdomyosarcomas (RMS) are the most frequent soft tissue sarcomas in children that share many features of developing skeletal muscle. We have discovered that a T-box family member, TBX2, is highly up regulated in tumor cells of both major RMS subtypes. TBX2 is a repressor that is often over expressed in cancer cells and is thought to function in bypassing cell growth control, including repression of p14 and p21. The cell cycle regulator p21 is required for the terminal differentiation of skeletal muscle cells and is silenced in RMS cells. We have found that TBX2 interacts with the myogenic regulatory factors MyoD and myogenin and inhibits the activity of these factors. TBX2 is expressed in primary myoblasts and C2C12 cells, but is strongly down regulated upon differentiation. TBX2 recruits the histone deacetylase HDAC1 and is a potent inhibitor of the expression of muscle specific genes and the cell cycle regulators, p21 and p14. TBX2 promotes the proliferation of RMS cells and either depletions of TBX2 or dominant negative TBX2 up regulate p21 and muscle specific genes. Significantly, depletion or interference with TBX2 completely inhibits tumor growth in a xenograft assay, highlighting the oncogenic role of TBX2 in RMS cells. Thus, the data demonstrate that elevated expression of TBX2 contributes to the pathology of RMS cells by promoting proliferation and repressing differentiation specific gene expression. These results show that deregulated TBX2 serves as an oncogene in RMS, suggesting that TBX2 may serve as a new diagnostic marker or therapeutic target for RMS tumors. PMID:24470334

  11. 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. PMID:24817642

  12. 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.

  13. Steel factor controls midline cell death of primordial germ cells and is essential for their normal proliferation and migration.

    PubMed

    Runyan, Christopher; Schaible, Kyle; Molyneaux, Kathleen; Wang, Zhuoqiao; Levin, Linda; Wylie, Christopher

    2006-12-01

    During germ-cell migration in the mouse, the dynamics of embryo growth cause many germ cells to be left outside the range of chemoattractive signals from the gonad. At E10.5, movie analysis has shown that germ cells remaining in the midline no longer migrate directionally towards the genital ridges, but instead rapidly fragment and disappear. Extragonadal germ cell tumors of infancy, one of the most common neonatal tumors, are thought to arise from midline germ cells that failed to die. This paper addresses the mechanism of midline germ cell death in the mouse. We show that at E10.5, the rate of apoptosis is nearly four-times higher in midline germ cells than those more laterally. Gene expression profiling of purified germ cells suggests this is caused by activation of the intrinsic apoptotic pathway. We then show that germ cell apoptosis in the midline is activated by down-regulation of Steel factor (kit ligand) expression in the midline between E9.5 and E10.5. This is confirmed by the fact that removal of the intrinsic pro-apoptotic protein Bax rescues the germ-cell apoptosis seen in Steel null embryos. Two interesting things are revealed by this: first, germ-cell proliferation does not take place in these embryos after E9.0; second, migration of germ cells is highly abnormal. These data show first that changing expression of Steel factor is required for normal midline germ cell death, and second, that Steel factor is required for normal proliferation and migration of germ cells. PMID:17107997

  14. Activator of G Protein Signaling 3 Promotes Epithelial Cell Proliferation in PKD

    PubMed Central

    Nadella, Rama; Blumer, Joe B.; Jia, Guangfu; Kwon, Michelle; Akbulut, Talha; Qian, Feng; Sedlic, Filip; Wakatsuki, Tetsuro; Sweeney, William E.; Wilson, Patricia D.; Lanier, Stephen M.

    2010-01-01

    The activation of heterotrimeric G protein signaling is a key feature in the pathophysiology of polycystic kidney diseases (PKD). In this study, we report abnormal overexpression of activator of G protein signaling 3 (AGS3), a receptor-independent regulator of heterotrimeric G proteins, in rodents and humans with both autosomal recessive and autosomal dominant PKD. Increased AGS3 expression correlated with kidney size, which is an index of severity of cystic kidney disease. AGS3 expression localized exclusively to distal tubular segments in both normal and cystic kidneys. Short hairpin RNA–induced knockdown of endogenous AGS3 protein significantly reduced proliferation of cystic renal epithelial cells by 26 ± 2% (P < 0.001) compared with vehicle-treated and control short hairpin RNA–expressing epithelial cells. In summary, this study suggests a relationship between aberrantly increased AGS3 expression in renal tubular epithelia affected by PKD and epithelial cell proliferation. AGS3 may play a receptor-independent role to regulate Gα subunit function and control epithelial cell function in PKD. PMID:20488951

  15. The proliferation and differentiation of stem cell journals.

    PubMed

    Sanberg, Paul R; Borlongan, Cesar V

    2010-12-01

    As scientists position themselves in translating the therapeutic potential of stem cells from laboratory to clinical applications, publishing companies have taken this rapidly evolving field as a unique opportunity to launch new journals for dissemination of stem cell research. Over the last decade, the significant increase in the number of stem cell-based journals has created a conundrum. At stake is the pressure for these new journals to build their reputation by maintaining publication standards, while at the same time attracting a cadre of stem cell researchers to consider their journals as the publication of choice. We discuss here a prophetic path of survival for these journals which likely will closely mimic the core scientific and translational value of stem cells, namely their capacity to proliferate and differentiate into something meaningful! PMID:20694581

  16. Silencing of CDC42 inhibits neuroblastoma cell proliferation and transformation

    PubMed Central

    Lee, Sora; Craig, Brian T.; Romain, Carmelle V.; Qiao, Jingbo; Chung, Dai H.

    2014-01-01

    Cell division cycle 42 (CDC42), a small GTPase of the Rho-subfamily, regulates diverse cellular functions including proliferation, cytoskeletal rearrangement and even promotes malignant transformation. Here, we found that increased expression of CDC42 correlated with undifferentiated neuroblastoma as compared to a more benign phenotype. CDC42 inhibition decreased cell growth and soft agar colony formation, and increased cell death in BE(2)-C and BE(2)-M17 cell lines, but not in SK-N-AS. In addition, silencing of CDC42 decreased expression of N-myc in BE(2)-C and BE(2)-M17 cells. Our findings suggest that CDC42 may play a role in the regulation of aggressive neuroblastoma behavior. PMID:25264923

  17. Sesquiterpenoid Lactones in Tanacetum huronense Inhibit Human Glioblastoma Cell Proliferation.

    PubMed

    Dissanayake, Amila A; Bejcek, Bruce E; Zhang, Chuan-Rui; Nair, Muraleedharan G

    2016-05-01

    Tanacetum huronense (Lake Huron tansy), which is native to the upper Midwest region of USA and Canada, was examined for the presence of anticancer compounds using an in vitro human tumor cell proliferation inhibition assay, with glioblastoma derived cell line U-87 MG. Bioassay-directed purification of the ethyl acetate extract of the aerial portion of this plant identified six active sesquiterpenoid lactones (1-6). Among these, compounds 5 and 6 are new structural analogs. One of the most abundant isolates, tanacin (4), exhibited the greatest inhibition with an IC50 value of 4.5 μg/mL. PMID:27319121

  18. Mast cells and histamine enhance the proliferation of non-small cell lung cancer cells.

    PubMed

    Stoyanov, Evgeniy; Uddin, Mohib; Mankuta, David; Dubinett, Steven M; Levi-Schaffer, Francesca

    2012-01-01

    Non-small cell lung cancer (NSCLC) is the most common form of lung cancer with an extremely low survival rate. It is characterized by a chronic inflammatory process with intense mast cell infiltrate that is associated with reduced survival. The aim of this study was to test the hypothesis that mast cells have an enhancing effect on NSCLC proliferation. To assess the tumor-promoting potential of mast cells, we used the human alveolar basal adenocarcinoma (A549) and the mouse Lewis lung carcinoma (LLC) cell lines, umbilical cord blood-derived mast cells (CBMC) and the mast cell-deficient mouse Sash model. The proliferation rate of A549/LLC cells was markedly increased by mast cells and histamine. Histamine proliferating activity was mediated via H(1), H(2) and H(4) receptors and caused ERK phosphorylation. LLC induced in Sash mice or in wild-type mice treated with the mast cell stabilizer nedocromil sodium displayed an accelerated growth (number of metastic colonies in the lungs, total lung area and lung/total mice weight ratio). In summary, we have shown a significant effect of mast cells and histamine in enhancing NSCLC/LLCX growth in vitro, while in a mouse LLC model in vivo we have found that mast cells are important negative regulators of cancer development. Therefore our results would indicate a pro-tumorogenic effect of the mast cells in vitro on established lung tumor cell lines, and anti-tumorogenic effect in mice at lung cancer induction. In conclusion, mast cell/anti-histamine targeted therapies should carefully consider this dual effect. PMID:21733595

  19. miR-367 promotes proliferation and stem-like traits in medulloblastoma cells

    PubMed Central

    Kaid, Carolini; Silva, Patrícia B G; Cortez, Beatriz A; Rodini, Carolina O; Semedo-Kuriki, Patricia; Okamoto, Oswaldo K

    2015-01-01

    In medulloblastoma, abnormal expression of pluripotency factors such as LIN28 and OCT4 has been correlated with poor patient survival. The miR-302/367 cluster has also been shown to control self-renewal and pluripotency in human embryonic stem cells and induced pluripotent stem cells, but there is limited, mostly correlational, information about these pluripotency-related miRNA in cancer. We evaluated whether aberrant expression of such miRNA could affect tumor cell behavior and stem-like traits, thereby contributing to the aggressiveness of medulloblastoma cells. Basal expression of primary and mature forms of miR-367 were detected in four human medulloblastoma cell lines and expression of the latter was found to be upregulated upon enforced expression of OCT4A. Transient overexpression of miR-367 significantly enhanced tumor features typically correlated with poor prognosis; namely, cell proliferation, 3-D tumor spheroid cell invasion and the ability to generate neurosphere-like structures enriched in CD133 expressing cells. A concurrent downregulation of the miR-367 cancer-related targets RYR3, ITGAV and RAB23, was also detected in miR-367-overexpressing cells. Overall, these findings support the pro-oncogenic activity of miR-367 in medulloblastoma and reveal a possible mechanism contributing to tumor aggressiveness, which could be further explored to improve patient stratification and treatment of this important type of pediatric brain cancer. PMID:26250335

  20. 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

  1. Site-specific Proteasome Phosphorylation Controls Cell Proliferation and Tumorigenesis

    PubMed Central

    Guo, Xing; Wang, Xiaorong; Wang, Zhiping; Banerjee, Sourav; Yang, Jing; Huang, Lan; Dixon, Jack E.

    2015-01-01

    Despite the fundamental importance of proteasomal degradation in cells, little is known about whether and how the 26S proteasome itself is regulated in coordination with various physiological processes. Here we show that the proteasome is dynamically phosphorylated during cell cycle at Thr25 of the 19S subunit Rpt3. CRISPR/Cas9-mediated genome editing, RNA interference and biochemical studies demonstrate that blocking Rpt3-Thr25 phosphorylation markedly impairs proteasome activity and impedes cell proliferation. Through a kinome-wide screen, we have identified dual-specificity tyrosine-regulated kinase 2 (DYRK2) as the primary kinase that phosphorylates Rpt3-Thr25, leading to enhanced substrate translocation and degradation. Importantly, loss of the single phosphorylation of Rpt3-Thr25 or knockout of DYRK2 significantly inhibits tumor formation by proteasome-addicted human breast cancer cells in mice. These findings define an important mechanism for proteasome regulation and demonstrate the biological significance of proteasome phosphorylation in regulating cell proliferation and tumorigenesis. PMID:26655835

  2. Fibronectin adsorption, cell adhesion, and proliferation on nanostructured tantalum surfaces.

    PubMed

    Dolatshahi-Pirouz, A; Jensen, T; Kraft, David Christian; Foss, Morten; Kingshott, Peter; Hansen, John Lundsgaard; Larsen, Arne Nylandsted; Chevallier, Jacques; Besenbacher, Flemming

    2010-05-25

    The interaction between dental pulp derived mesenchymal stem cells (DP-MSCs) and three different tantalum nanotopographies with and without a fibronectin coating is examined: sputter-coated tantalum surfaces with low surface roughness <0.2 nm, hut-nanostructured surfaces with a height of 2.9 +/- 0.6 nm and a width of 35 +/- 8 nm, and dome structures with a height of 13 +/- 2 nm and a width of 52 +/- 14 nm. Using ellipsometry, the adsorption and the availability of fibronectin cell-binding domains on the tantalum surfaces were examined, as well as cellular attachment, proliferation, and vinculin focal adhesion spot assembly on the respective surfaces. The results showed the highest fibronectin mass uptake on the hut structures, with a slightly higher availability of cell-binding domains and the most pronounced formation of vinculin focal adhesion spots as compared to the other surfaces. The proliferation of DP-MSCs was found to be significantly higher on dome and hut surfaces coated with fibronectin compared to the uncoated flat tantalum surfaces. Consequently, the results presented in this study indicate that fibronectin-coated nanotopographies with a vertical dimension of less than 5 nm influence cell adhesion. This rather interesting behavior is argued to originate from the more available fibronectin cell-binding domains observed on the hut structures. PMID:20443575

  3. 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

  4. 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. PMID:27179667

  5. Myelin-phagocytosing macrophages modulate autoreactive T cell proliferation

    PubMed Central

    2011-01-01

    Introduction Multiple sclerosis (MS) is a chronic, inflammatory, demyelinating disease of the central nervous system (CNS) in which macrophages play a central role. Initially, macrophages where thought to be merely detrimental in MS, however, recent evidence suggests that their functional phenotype is altered following myelin phagocytosis. Macrophages that have phagocytosed myelin may be less inflammatory and may exert beneficial effects. The presence of myelin-containing macrophages in CNS-draining lymph nodes and perivascular spaces of MS patients suggests that these cells are ideally positioned to exert an immune regulatory role. Therefore we evaluated in this study the effect of myelin-phagocytosing macrophages on lymphocyte reactivity. Methods Thioglycolate-elicited rat peritoneal macrophages were loaded with myelin and cocultured with myelin-basic protein (MBP) or ovalbumin (OVA) reactive lymphocytes. Lymphocyte proliferation was determined by CFSE-labeling. The role of nitric oxide in regulating lymphocyte proliferation was assessed by addition of an inhibitor of inducible nitric oxide synthase to the coculture. In vivo immune regulation was investigated by treating MBP- and OVA-immunized animals subcutaneously with myelin. Cognate antigen specific lymphocyte proliferation and nitric oxide production were determined 9d post-immunization. Results In this study we demonstrate that myelin-phagocytosing macrophages inhibit TCR-triggered lymphocyte proliferation in an antigen-independent manner. The observed immune suppression is mediated by an increase in NO production by myelin-phagocytosing macrophages upon contact with lymphocytes. Additionally, myelin delivery to primarily CD169+ macrophages in popliteal lymph nodes of OVA-immunized animals results in a reduced cognate antigen specific proliferation. In contrast to OVA-immunized animals, lymphocytes from MBP-immunized animals displayed an increased proliferation after stimulation with their cognate antigen

  6. TLR2 Activation Inhibits Embryonic Neural Progenitor Cell Proliferation

    PubMed Central

    Okun, Eitan; Griffioen, Kathleen J.; Gen-Son, Tae; Lee, Jong-Hwan; Roberts, Nicholas J.; Mughal, Mohamed R.; Hutchison, Emmette; Cheng, Aiwu; Arumugam, Thiruma V.; Lathia, Justin D.; van Praag, Henriette; Mattson, Mark P.

    2010-01-01

    Toll-like receptors (TLRs) play essential roles in innate immunity, and increasing evidence indicates that these receptors are expressed in neurons, astrocytes and microglia in the brain, where they mediate responses to infection, stress and injury. To address the possibility that TLR2 heterodimer activation could affect progenitor cells in the developing brain, we analyzed the expression of TLR2 throughout the mouse cortical development, and assessed the role of TLR2 heterodimer activation in neural progenitor cell (NPC) proliferation. TLR2 mRNA and protein was expressed in the cortex in embryonic and early postnatal stages of development, and in cultured cortical NPC. While NPC from TLR2-deficient and wild type embryos had the same proliferative capacity, TLR2 activation by the synthetic bacterial lipopeptides Pam3CSK4 and FSL1, or low molecular weight hyaluronan, an endogenous ligand for TLR2, inhibited neurosphere formation in vitro. Intracerebral in utero administration of TLR2 ligands resulted in ventricular dysgenesis characterized by increased ventricle size, reduced proliferative area around the ventricles, increased cell density, an increase in PH3+ cells and a decrease in BrdU+ cells in the sub-ventricular zone. Our findings indicate that loss of TLR2 does not result in defects in cerebral development. However, TLR2 is expressed and functional in the developing telencephalon from early embryonic stages and infectious agent-related activation of TLR2 inhibits NPC proliferation. TLR2–mediated inhibition of NPC proliferation may therefore be a mechanism by which infection, ischemia and inflammation adversely affect brain development. PMID:20456021

  7. Slit/Robo1 signaling regulates neural tube development by balancing neuroepithelial cell proliferation and differentiation

    SciTech Connect

    Wang, Guang; Li, Yan; Wang, Xiao-yu; Han, Zhe; Chuai, Manli; Wang, Li-jing; Ho Lee, Kenneth Ka; Geng, Jian-guo; Yang, Xuesong

    2013-05-01

    Formation of the neural tube is the morphological hallmark for development of the embryonic central nervous system (CNS). Therefore, neural tube development is a crucial step in the neurulation process. Slit/Robo signaling was initially identified as a chemo-repellent that regulated axon growth cone elongation, but its role in controlling neural tube development is currently unknown. To address this issue, we investigated Slit/Robo1 signaling in the development of chick neCollege of Life Sciences Biocentre, University of Dundee, Dundee DD1 5EH, UKural tube and transgenic mice over-expressing Slit2. We disrupted Slit/Robo1 signaling by injecting R5 monoclonal antibodies into HH10 neural tubes to block the Robo1 receptor. This inhibited the normal development of the ventral body curvature and caused the spinal cord to curl up into a S-shape. Next, Slit/Robo1 signaling on one half-side of the chick embryo neural tube was disturbed by electroporation in ovo. We found that the morphology of the neural tube was dramatically abnormal after we interfered with Slit/Robo1 signaling. Furthermore, we established that silencing Robo1 inhibited cell proliferation while over-expressing Robo1 enhanced cell proliferation. We also investigated the effects of altering Slit/Robo1 expression on Sonic Hedgehog (Shh) and Pax7 expression in the developing neural tube. We demonstrated that over-expressing Robo1 down-regulated Shh expression in the ventral neural tube and resulted in the production of fewer HNK-1{sup +} migrating neural crest cells (NCCs). In addition, Robo1 over-expression enhanced Pax7 expression in the dorsal neural tube and increased the number of Slug{sup +} pre-migratory NCCs. Conversely, silencing Robo1 expression resulted in an enhanced Shh expression and more HNK-1{sup +} migrating NCCs but reduced Pax7 expression and fewer Slug{sup +} pre-migratory NCCs were observed. In conclusion, we propose that Slit/Robo1 signaling is involved in regulating neural tube

  8. 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

  9. Astaxanthin Inhibits Proliferation and Induces Apoptosis and Cell Cycle Arrest of Mice H22 Hepatoma Cells.

    PubMed

    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 AND 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

  10. Exosomes Secreted by Toxoplasma gondii-Infected L6 Cells: Their Effects on Host Cell Proliferation and Cell Cycle Changes

    PubMed Central

    Kim, Min Jae; Jung, Bong-Kwang; Cho, Jaeeun; Song, Hyemi; Pyo, Kyung-Ho; Lee, Ji Min; Kim, Min-Kyung; Chai, Jong-Yil

    2016-01-01

    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. PMID:27180572

  11. 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.

  12. A highly selective telomerase inhibitor limiting human cancer cell proliferation

    PubMed Central

    Damm, Klaus; Hemmann, Ulrike; Garin-Chesa, Pilar; Hauel, Norbert; Kauffmann, Iris; Priepke, Henning; Niestroj, Claudia; Daiber, Christine; Enenkel, Barbara; Guilliard, Bernd; Lauritsch, Ines; Müller, Elfriede; Pascolo, Emanuelle; Sauter, Gabriele; Pantic, Milena; Martens, Uwe M.; Wenz, Christian; Lingner, Joachim; Kraut, Norbert; Rettig, Wolfgang J.; Schnapp, Andreas

    2001-01-01

    Telomerase, the ribonucleoprotein enzyme maintaining the telomeres of eukaryotic chromosomes, is active in most human cancers and in germline cells but, with few exceptions, not in normal human somatic tissues. Telomere maintenance is essential to the replicative potential of malignant cells and the inhibition of telomerase can lead to telomere shortening and cessation of unrestrained proliferation. We describe novel chemical compounds which selectively inhibit telomerase in vitro and in vivo. Treatment of cancer cells with these inhibitors leads to progressive telomere shortening, with no acute cytotoxicity, but a proliferation arrest after a characteristic lag period with hallmarks of senescence, including morphological, mitotic and chromosomal aberrations and altered patterns of gene expression. Telomerase inhibition and telomere shortening also result in a marked reduction of the tumorigenic potential of drug-treated tumour cells in a mouse xenograft model. This model was also used to demonstrate in vivo efficacy with no adverse side effects and uncomplicated oral administration of the inhibitor. These findings indicate that potent and selective, non-nucleosidic telomerase inhibitors can be designed as novel cancer treatment modalities. PMID:11742973

  13. Proliferation of human mammary cancer cells exposed to 27-hydroxycholesterol

    PubMed Central

    CRUZ, PAMELA; TORRES, CRISTIAN; RAMÍREZ, MARÍA EUGENIA; EPUÑÁN, MARÍA JOSÉ; VALLADARES, LUIS EMILIO; SIERRALTA, WALTER DANIEL

    2010-01-01

    The aim of the present study was to identify the possible mechanisms by which certain estradiol receptor (ER)-positive mammary tumor cells remain resistant to treatment with anti-estrogens or inhibitors of local estradiol (E2) production. To this end, we compared the proliferative effects on mammary cancer cells of the novel selective ER modulator 27-hydroxycholesterol (27OHC) to those of E2, and evaluated their inhibition by ICI 182,780 (ICI). Analysis of the effects on the cell cycle of 27OHC and E2 in the absence or presence of ICI was conducted. In ER-positive mammary tumor cells, we detected the blocking of 27OHC proliferation-stimulatory activity by simvastatin, as well as the inhibition of E2-stimulated proliferation by an α-fetoprotein-derived cyclic nonapeptide. The effects reported herein may be extrapolated to infiltrating mammary cancer, where the activity of local macrophages may stimulate tumor growth. We suggest that increased breast cancer growth in obese patients may be related to increased 27OHC circulatory levels. PMID:22993572

  14. TWEAK induces angiogenesis and proliferation of endothelial cells.

    PubMed

    Lynch, C N; Wang, Y C; Lund, J K; Chen, Y W; Leal, J A; Wiley, S R

    1999-03-26

    TWEAK is a recently described member of the Tumor Necrosis Factor (TNF) ligand family whose transcripts are present in a wide variety of human tissues (Chicheportiche, Y., Bourdon, P. R., Xu, H., Hsu Y. M., Scott, H., Hession, C., Garcia, I., and Browning, J. L. (1997) J. Biol. Chem. 272, 32401-32410). TWEAK is a weak inducer of apoptosis in transformed cells when administered with interferon-gamma or cycloheximide (Chicheportiche, Y., Bourdon, P. R., Xu, H., Hsu Y. M., Scott, H., Hession, C., Garcia, I., and Browning, J. L. (1997) J. Biol. Chem. 272, 32401-32410; Masters, S. A., Sheridan, J. P., Pitti, R. M., Brush, A. G., and Ashkenazi, A. (1998) Curr. Biol. 8, 525-528) and also promotes IL-8 secretion in cultured cells. We report here that picomolar concentrations of recombinant soluble TWEAK induce proliferation in a variety of normal human endothelial cells and in aortic smooth muscle cells and reduce culture requirements for serum and growth factors. Blocking antibodies to Vascular Endothelial Growth Factor (VEGF) do not significantly inhibit TWEAK-induced proliferation, indicating that TWEAK does not function indirectly through up-regulation of VEGF. Pellets containing TWEAK induce a strong angiogenic response when implanted in rat corneas, suggesting a role for TWEAK in vasculature formation in vivo. PMID:10085077

  15. Actein Inhibits Cell Proliferation and Migration in Human Osteosarcoma

    PubMed Central

    Chen, Zhi; Wu, Jingdong; Guo, Qinghao

    2016-01-01

    Background Osteosarcoma is one of the most common malignant bone cancers worldwide. Although the traditional chemotherapies have made some progression in the past decades, the mortality of osteosarcoma in children and adolescent is very high. Herein, the role of actein in osteosarcoma was explored. Material/Methods Cell viability assay was performed in osteosarcoma cell lines 143B and U2OS. Colony formation analysis was included when cells were treated with different doses of actin. Cell cycle assay was conducted to further examine the role of actein. Cell apoptotic rate and the relative activities of caspase-3, caspase-8, and caspase-9 were detected in 143B and U2OS osteosarcoma cells. Moreover, transwell assays were used to explore the effects of actein on cell metastasis. Results Actein significantly inhibited osteosarcoma cell viability in a time- and dose-dependent manner. Actein also dramatically suppressed the colony formation ability in osteosarcoma143B and U2OS cells. It was revealed that osteosarcoma cells were arrested in G0/G1 phase in the cell cycle progression and induced to apoptosis by administration of actein. The activities of pro-apoptotic factors such as caspase-3 and caspase-9 were significantly increased by actein. Furthermore, administration of actein decreased cell migrated and invasive abilities in both 143B and U2OS cell lines. Conclusions Actein inhibits tumor growth by inducing cell apoptosis in osteosarcoma. The inhibitive roles of actein in cell proliferation, migration and invasion suggest that actein may serve as a potential therapeutic agent in the treatment of osteosarcoma. PMID:27173526

  16. GLIAL ABNORMALITIES IN MOOD DISORDERS

    PubMed Central

    Öngür, Dost; Bechtholt, Anita J.; Carlezon, William A.; Cohen, Bruce M.

    2015-01-01

    Multiple lines of evidence indicate that mood disorders are associated with abnormalities in the brain's cellular composition, especially in glial cells. Considered inert support cells in the past, glial cells are now known to be important for brain function. Treatments for mood disorders enhance glial cell proliferation, and experimental stimulation of cell growth has antidepressant effects in animal models of mood disorders. These findings suggest that the proliferation and survival of glial cells may be important in the pathogenesis of mood disorders and may be possible targets for the development of new treatments. In this chapter, we will review the evidence for glial abnormalities in mood disorders. We will discuss glial cell biology and evidence from postmortem studies of mood disorders. This is not carry out a comprehensive review; rather we selectively discuss existing evidence in building an argument for the role of glial cells in mood disorders. PMID:25377605

  17. Matrix stiffness-modulated proliferation and secretory function of the airway smooth muscle cells.

    PubMed

    Shkumatov, Artem; Thompson, Michael; Choi, Kyoung M; Sicard, Delphine; Baek, Kwanghyun; Kim, Dong Hyun; Tschumperlin, Daniel J; Prakash, Y S; Kong, Hyunjoon

    2015-06-01

    Multiple pulmonary conditions are characterized by an abnormal misbalance between various tissue components, for example, an increase in the fibrous connective tissue and loss/increase in extracellular matrix proteins (ECM). Such tissue remodeling may adversely impact physiological function of airway smooth muscle cells (ASMCs) responsible for contraction of airways and release of a variety of bioactive molecules. However, few efforts have been made to understand the potentially significant impact of tissue remodeling on ASMCs. Therefore, this study reports how ASMCs respond to a change in mechanical stiffness of a matrix, to which ASMCs adhere because mechanical stiffness of the remodeled airways is often different from the physiological stiffness. Accordingly, using atomic force microscopy (AFM) measurements, we found that the elastic modulus of the mouse bronchus has an arithmetic mean of 23.1 ± 14 kPa (SD) (median 18.6 kPa). By culturing ASMCs on collagen-conjugated polyacrylamide hydrogels with controlled elastic moduli, we found that gels designed to be softer than average airway tissue significantly increased cellular secretion of vascular endothelial growth factor (VEGF). Conversely, gels stiffer than average airways stimulated cell proliferation, while reducing VEGF secretion and agonist-induced calcium responses of ASMCs. These dependencies of cellular activities on elastic modulus of the gel were correlated with changes in the expression of integrin-β1 and integrin-linked kinase (ILK). Overall, the results of this study demonstrate that changes in matrix mechanics alter cell proliferation, calcium signaling, and proangiogenic functions in ASMCs. PMID:25724668

  18. Conditional IL-2 Gene Deletion: Consequences for T Cell Proliferation

    PubMed Central

    Popmihajlov, Zoran; Xu, Dong; Morgan, Heather; Milligan, Zoie; Smith, Kendall A.

    2012-01-01

    To explore the role of interleukin-2 (IL-2) in T cell proliferation, and to circumvent the IL-2 deficiency autoimmune syndrome of conventional il2 gene deletion, mice were created to allow conditional il2 gene deletion when treated with the estrogen analog, tamoxifen (TAM) as adults. Splenocytes from four different mouse strains, C57Bl/6 wild type (WT), conventional IL-2(−/−), TAM-treated Cre recombinase-negative (Cre−)/IL2fl/fl, and Cre recombinase-positive (Cre+)/IL2fl/fl, were activated with anti-CD3 and anti-CD28, and monitored for CD4+ and CD8+ T cell lymphocyte blastogenesis, aerobic glycolysis, BrdU incorporation into newly synthesized DNA, and CFSE dye dilution to monitor cell division. IL-2 production was monitored by quantitative ELISA and multiple additional cytokines were monitored by quantitative protein-bead arrays. Splenocytes from conventional IL-2(−/−) and TAM-treated Cre+ mice resulted in undetectable IL-2 production by ELISA, so that both strains were IL-2-deficient. As monitored by flow cytometry, activated CD4+ and CD8+ T cells from WT, Cre+, and Cre− mice all underwent blastogenesis, whereas far fewer cells from conventional IL-2(−/−) mice did so. By comparison, only cells from IL-2 sufficient WT and Cre− mice switched to aerobic glycolysis as evidenced by a drop in media pH. Blastogenesis was mirrored by BrdU incorporation and CFSE dye dilution by CD4+ and CD8+ T cells from WT, Cre+, and Cre− mice, which were all equivalent, while proliferation of cells from conventional IL-2(−/−) mice was compromised. Splenocytes from IL-2 deficient conventional IL-2(−/−) mice produced low or undetectable other γc-chain cytokines (IL-4, IL-7, IL-9, IL-13, IL-15, and IL-21), whereas production of these γc-chain cytokines from IL-2-deficient conditional IL-2(−/−) Cre+ mice were comparable with WT and Cre− mice. These results indicate that CD4+ and CD8+ T cell blastogenesis cannot be attributable to IL-2 alone, but a switch

  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. Abnormal Mitochondrial Function and Impaired Granulosa Cell Differentiation in Androgen Receptor Knockout Mice

    PubMed Central

    Wang, Ruey-Sheng; Chang, Heng-Yu; Kao, Shu-Huei; Kao, Cheng-Heng; Wu, Yi-Chen; Yeh, Shuyuan; Tzeng, Chii-Reuy; Chang, Chawnshang

    2015-01-01

    In the ovary, the paracrine interactions between the oocyte and surrounded granulosa cells are critical for optimal oocyte quality and embryonic development. Mice lacking the androgen receptor (AR−/−) were noted to have reduced fertility with abnormal ovarian function that might involve the promotion of preantral follicle growth and prevention of follicular atresia. However, the detailed mechanism of how AR in granulosa cells exerts its effects on oocyte quality is poorly understood. Comparing in vitro maturation rate of oocytes, we found oocytes collected from AR−/− mice have a significantly poor maturating rate with 60% reached metaphase II and 30% remained in germinal vesicle breakdown stage, whereas 95% of wild-type AR (AR+/+) oocytes had reached metaphase II. Interestingly, we found these AR−/− female mice also had an increased frequency of morphological alterations in the mitochondria of granulosa cells with reduced ATP generation (0.18 ± 0.02 vs. 0.29 ± 0.02 µM/mg protein; p < 0.05) and aberrant mitochondrial biogenesis. Mechanism dissection found loss of AR led to a significant decrease in the expression of peroxisome proliferator-activated receptor γ (PPARγ) co-activator 1-β (PGC1-β) and its sequential downstream genes, nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM), in controlling mitochondrial biogenesis. These results indicate that AR may contribute to maintain oocyte quality and fertility via controlling the signals of PGC1-β-mediated mitochondrial biogenesis in granulosa cells. PMID:25941928

  1. 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. PMID:27514448

  2. Evodiamine inhibits the proliferation of leukemia cell line K562 by regulating peroxisome proliferators-activated receptor gamma (PPARγ) pathway.

    PubMed

    Sun, Chengming; Zhang, Guili; Luan, Shuping; Luan, Caifu; Shao, Huiyuan; Dong, Fei; Liu, Xuena

    2016-08-01

    Evodiamine, a quinolone alkaloid, is one of the major bioactive compounds of Evodia rutaecarpa Bentham (Rutaceae). It exhibits excellent biological activities, especially the anticancer activity. This study aims to investigate the effect of evodiamine on the proliferation of leukemia cell line K562 and to explore the underlying mechanism. The effect of evodiamine on K562 cells proliferation was analyzed by trypan blue dye exclusion assay and MTT assay. The expression levels of peroxisome proliferators-activated receptor gamma (PPARγ), cyclin D1, and p21 were detected by western blot assay. The results demonstrated that evodiamine inhibited the proliferation and decreased the viability of K562 cells in a dose- and time-dependent manner. 2-Chloro-5-nitro-N-phenylbenzamide (GW9662) and/or PPARγ-siRNA pretreatment alleviated the cell growth suppression triggered by evodiamine. Meanwhile, evodiamine intervention elevated the expression of PPARγ in K562 cells, while pretreatment with GW9662 attenuated the enhanced upregulation of PPARγ expression induced by evodiamine. In addition, GW9662 and PPARγ-siRNA pretreatment also significantly attenuated the downregulation of the cell cycle control protein cyclin D1 and the upregulation of cyclin-dependent kinase inhibitor p21 induced by evodiamine. In conclusion, PPARγ signaling pathway may involve in the proliferation inhibition of evodiamine on K562 cells via inhibiting cylcin D1 and stimulating of p21. PMID:26671528

  3. Chromatin assembly factor 1, subunit A (P150) facilitates cell proliferation in human hepatocellular carcinoma

    PubMed Central

    Xu, Meng; Jia, Yuli; Liu, Zhikui; Ding, Linglong; Tian, Run; Gu, Hua; Wang, Yufeng; Zhang, Hongyong; Tu, Kangsheng; Liu, Qingguang

    2016-01-01

    Several studies have revealed that the abnormal expression of chromatin assembly factor 1, subunit A (P150) (CHAF1A) was involved in the development of some types of malignant tumors. However, CHAF1A expression and its role in hepatocellular carcinoma (HCC) remain poorly characterized. In this study, we first investigated CHAF1A expression in six cell lines and 116 pairs of HCC and matched normal tumor-adjacent tissues to evaluate the clinicopathological characteristics of CHAF1A in HCC. Then, we detected the proliferation and apoptosis in HCC cells. In addition, a subcutaneous tumor model in nude mice was performed to evaluate tumor growth in vivo. We found that the expression of CHAF1A was significantly higher in HCC tissues than that in adjacent nontumor tissues (P<0.01). Clinical analysis indicated that CHAF1A expression was significantly correlated with the tumor–node–metastasis stage, tumor number, and tumor differentiation in HCC tissues (P<0.05, respectively). We also found that CHAF1A may potentially function as a poor prognostic indicator for 5-year overall and disease-free survival in patients with HCC (P<0.05, respectively). The elevated expression of CHAF1A was also observed in HCC cell lines compared with that in normal LO2 hepatic cell line (P<0.01). HCC cancer cells exhibited inhibition of cell growth, reduction in colony-formation ability, increased cell apoptosis rate, and impaired tumorigenicity in nude mice after CHAF1A knockdown. Collectively, we propose that CHAF1A by potentially mediating cancer cell proliferation plays an important role in promoting the development of HCC and may serve as a potential therapeutic target in HCC. PMID:27445493

  4. 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.

  5. Hyaluronan in aged collagen matrix increases prostate epithelial cell proliferation

    PubMed Central

    Damodarasamy, Mamatha; Vernon, Robert B.; Chan, Christina K.; Plymate, Stephen R.; Wight, Thomas N.

    2015-01-01

    The extracellular matrix (ECM) of the prostate, which is comprised primarily of collagen, becomes increasingly disorganized with age, a property that may influence the development of hyperplasia and cancer. Collageous ECM extracted from the tails of aged mice exhibits many characteristics of collagen in aged tissues, including the prostate. When polymerized into a 3-dimensional (3D) gel, these collagen extracts can serve as models for the study of specific cell-ECM interactions. In the present study, we examined the behaviors of human prostatic epithelial cell lines representing normal prostate epithelial cells (PEC), benign prostatic hyperplasia (BPH-1), and adenocarcinoma (LNCaP) cultured in contact with 3D gels made from collagen extracts of young and aged mice. We found that proliferation of PEC, BPH-1, and LNCaP cells were all increased by culture on aged collagen gels relative to young collagen gels. In examining age-associated differences in the composition of the collagen extracts, we found that aged and young collagen had a similar amount of several collagen-associated ECM components, but aged collagen had a much greater content of the glycosaminoglycan hyaluronan (HA) than young collagen. The addition of HA (of similar size and concentration to that found in aged collagen extracts) to cells placed in young collagen elicited significantly increased proliferation in BPH-1 cells, but not in PEC or LNCaP cells, relative to controls not exposed to HA. Of note, histochemical analyses of human prostatic tissues showed significantly higher expression of HA in BPH and prostate cancer stroma relative to stroma of normal prostate. Collectively, these results suggest that changes in ECM involving increased levels of HA contribute to the growth of prostatic epithelium with aging. PMID:25124870

  6. Transferrin synthesis by small cell lung cancer cells acts as an autocrine regulator of cellular proliferation.

    PubMed Central

    Vostrejs, M; Moran, P L; Seligman, P A

    1988-01-01

    Since transferrin is required for cellular proliferation, we investigated transferrin synthesis by a small cell lung cancer line (NCI-H510) that survives in serum-free media without added transferrin. Immunoassays for human transferrin demonstrated that these cells contained immunoreactive human transferrin. Immunofluorescence studies showed that the protein is expressed on the surface of cells, presumably bound to transferrin receptor. Media conditioned by NCI-H510 cells support proliferation of human leukemic cells that would not survive in media lacking transferrin. [35S]Methionine incorporation documented transferrin synthesis by NCI-H510 cells as well as three other small cell lines. Transferrin synthesis by NCI-H510 cells increased more than 10-fold when cells entered active phases of the cell cycle, and this increase was seen before large increases in transferrin-receptor expression. Further experiments examining the effects of agents that affect iron metabolism show that the addition of transferrin-iron or hemin to the media is associated with a more rapid initial rate of proliferation and lower rates of transferrin synthesis than control cells. Gallium salts, which inhibit iron uptake, inhibited proliferation of these cells. If the cells recovered from this effect, transferrin synthesis remained greatly increased compared to control. We conclude that transferrin synthesis by these malignant cells is ultimately related to an iron requirement for cellular proliferation. It appears that this synthesized transferrin acts as part of an important autocrine mechanism permitting proliferation of these cells, and perhaps permitting tumor cell growth in vivo in areas not well vascularized. Images PMID:2839550

  7. Correct Timing of Proliferation and Differentiation is Necessary for Normal Inner Ear Development and Auditory Hair Cell Viability

    PubMed Central

    Kopecky, Benjamin J.; Jahan, Israt; Fritzsch, Bernd

    2013-01-01

    Background Hearing restoration through hair cell regeneration will require revealing the dynamic interactions between proliferation and differentiation during development to avoid the limited viability of regenerated hair cells. Pax2-Cre N-Myc conditional knockout (CKO) mice highlighted the need of N-Myc for proper neurosensory development and possible redundancy with L-Myc. The late-onset hair cell death in the absence of early N-Myc expression could be due to mis-regulation of genes necessary for neurosensory formation and maintenance, such as Neurod1, Atoh1, Pou4f3, and Barhl1. Results Pax2-Cre N-Myc L-Myc double CKO mice show that proliferation and differentiation are linked together through Myc and in the absence of both Mycs, altered proliferation and differentiation results in morphologically abnormal ears. In particular, the organ of Corti apex is re-patterned into a vestibular-like organization and the base is truncated and fused with the saccule. Conclusions These data indicate that therapeutic approaches to restore hair cells must take into account a dynamic interaction of proliferation and differentiation regulation of basic Helix-Loop-Helix transcription factors in attempts to stably replace lost cochlear hair cells. In addition, our data indicate that Myc is an integral component of the evolutionary transformation process that resulted in the organ of Corti development. PMID:23193000

  8. Epithelial Cell Proliferation Contributes to Airway Remodeling in Severe Asthma

    PubMed Central

    Cohen, Lance; E, Xueping; Tarsi, Jaime; Ramkumar, Thiruvamoor; Horiuchi, Todd K.; Cochran, Rebecca; DeMartino, Steve; Schechtman, Kenneth B.; Hussain, Iftikhar; Holtzman, Michael J.; Castro, Mario

    2007-01-01

    Rationale: Despite long-term therapy with corticosteroids, patients with severe asthma develop irreversible airway obstruction. Objectives: To evaluate if there are structural and functional differences in the airway epithelium in severe asthma associated with airway remodeling. Methods: In bronchial biopsies from 21 normal subjects, 11 subjects with chronic bronchitis, 9 subjects with mild asthma, and 31 subjects with severe asthma, we evaluated epithelial cell morphology: epithelial thickness, lamina reticularis (LR) thickness, and epithelial desquamation. Levels of retinoblastoma protein (Rb), Ki67, and Bcl-2 were measured, reflecting cellular proliferation and death. Terminal deoxynucleotidyl-mediated dUTP nick end labeling (TUNEL) was used to study cellular apoptosis. Measurements and Main Results: Airway epithelial and LR thickness was greater in subjects with severe asthma compared with those with mild asthma, normal subjects, and diseased control subjects (p = 0.009 and 0.033, respectively). There was no significant difference in epithelial desquamation between groups. Active, hypophosphorylated Rb expression was decreased (p = 0.002) and Ki67 was increased (p < 0.01) in the epithelium of subjects with severe asthma as compared with normal subjects, indicating increased cellular proliferation. Bcl-2 expression was decreased (p < 0.001), indicating decreased cell death suppression. There was a greater level of apoptotic activity in the airway biopsy in subjects with severe asthma as compared with the normal subjects using the TUNEL assay (p = 0.002), suggesting increased cell death. Conclusions: In subjects with severe asthma, as compared with subjects with mild asthma, normal subjects, and diseased control subjects, we found novel evidence of increased cellular proliferation in the airway contributing to a thickened epithelium and LR. These changes may contribute to the progressive decline in lung function and airway remodeling in patients with severe

  9. Induction of excessive B cell proliferation and differentiation by an in vitro stimulus in culture in human systemic lupus erythematosus.

    PubMed Central

    Suzuki, N; Sakane, T

    1989-01-01

    B cell hyperactivity present in the body in patients with systemic lupus erythematosus (SLE) can be detectable via almost any measure of B cell function. Nonetheless, the basis for the B cell hyperactivity is difficult to study in vitro. In this study, we have obtained the resting B cells from patients with entirely inactive SLE by collecting them sedimenting in a high density fraction on a Percoll density gradient. These resting SLE B cells proliferated in vitro at a higher rate than normal B cells when exposed to Staphylococcus aureus Cowan I (SAC). In addition, significant proliferation was observed earlier in the course of culture in SLE patients than in normal controls. Moreover, the SLE resting B cells, once triggered by SAC produced abnormally high numbers of immunoglobulin-secreting cells in response to T cell-derived soluble factors. There was less frequency of circulating Leu 1+ B cells in the SLE patients than in normal controls. Moreover, not only Leu 1+ B cells but also Leu 1- B cells of SLE patients were more responsive to SAC than those of normal controls. The results indicate that the B cell hyperactivity in human SLE can be induced by in vitro stimuli, and may not be limited to the Leu 1+ B cell subset. PMID:2646322

  10. Ustilago maydis reprograms cell proliferation in maize anthers

    PubMed Central

    Gao, Li; Kelliher, Timothy; Nguyen, Linda; Walbot, Virginia

    2013-01-01

    SUMMARY The basidiomycete Ustilago maydis is a ubiquitous pathogen of maize (Zea mays), one of the world’s most important cereal crops. Infection by this smut fungus triggers tumor formation in aerial plant parts within which the fungus sporulates. Using confocal microscopy to track U. maydis infection on corn anthers through 7 dpi (days post-injection), we found that U. maydis is located on the epidermis on the first two days and by 3 dpi has reached all anther lobe cell types. Fungal infection can alter cell fate specification events, cell division patterns, host cell expansion, and host cell senescence depending on the developmental stage and cell type. Fungal impacts on tassel and plant growth were also quantified. Transcriptome profiling using a dual organism microarray identified thousands of anther genes affected by fungal infection 3 dpi during the cell fate specification and rapid cell proliferation phases of anther development. 4147 (17%) of anther-expressed genes were altered by infection, 2018 fungal genes were expressed in anthers, and 206 fungal secretome genes may be anther-specific. The results confirm that U. maydis deploys distinctive genes to cause disease in specific maize organs and begins to chart the mechanisms by which the host plant is manipulated to generate a tumor. PMID:23795972

  11. 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.

  12. Regulation of cell proliferation and apoptosis by bioactive lipid mediators.

    PubMed

    Clària, Joan

    2006-11-01

    Bioactive lipid mediators are increasingly being recognized as important endogenous regulators of cell activation, signaling, apoptosis and proliferation. Most of these lipid mediators are originated from cleavage of constituents of cellular membranes under the activity of phospholipases and sphingomyelinases. One of the major cascades of bioactive lipid mediator production involves the release of arachidonic acid from membrane phospholipids followed by the formation of eicosanoids (i.e. prostaglandins, leukotrienes and lipoxins). These biologically active metabolites of arachidonic acid are emerging as key regulators of cell proliferation and neo-angiogenesis and agents that specifically target these lipid mediators are being investigated as potential anticancer drugs. On the other hand, the lysophospholipid family, which includes members of the sphingomyelin-ceramide-sphingosine-1-phosphate and lysophosphatidic acid subfamilies, has evolved as an important group of lipid signaling molecules implicated in cellular differentiation, cell growth and apoptosis. This article reviews the most recent patents in this field of research, covering the following strategies based on the modulation of bioactive lipid mediators: (1) prostaglandin H synthase-2 inhibitors, (2) lipoxin analogs and aspirin-triggered lipid mediators, and (3) lysophosphatidic acid and other lysophospholipids. PMID:18221047

  13. Cell phone radiation effects on cytogenetic abnormalities of oral mucosal cells.

    PubMed

    Daroit, Natália Batista; Visioli, Fernanda; Magnusson, Alessandra Selinger; Vieira, Geila Radunz; Rados, Pantelis Varvaki

    2015-01-01

    The aim of this study was to evaluate the effects of exposure to cell phone electromagnetic radiation on the frequency of micronuclei, broken eggs cells, binucleated cells, and karyorrhexis in epithelial cells of the oral mucosa. The sample was composed of 60 cell phone users, who were non-smokers and non-drinkers, and had no clinically visible oral lesions. Cells were obtained from anatomical sites with the highest incidence of oral cancer: lower lip, border of the tongue, and floor of the mouth. The Feulgen reaction was used for quantification of nuclear anomalies in 1,000 cells/slide. A slightly increase in the number of micronucleated cells in the lower lip and in binucleated cells on the floor of the mouth was observed in individuals who used their phones > 60 minutes/week. The analysis also revealed an increased number of broken eggs in the tongue of individuals owning a cell phone for over eight years. Results suggest that exposure to electromagnetic waves emitted by cell phones can increase nuclear abnormalities in individuals who use a cell phone for more than 60 minutes per week and for over eight years. Based on the present findings, we suggest that exposure to electromagnetic radiation emitted by cell phones may interfere with the development of metanuclear anomalies. Therefore, it is demonstrated that, despite a significant increase in these anomalies, the radiation emitted by cell phones among frequent users is within acceptable physiological limits. PMID:26486771

  14. Sertoli cells promote proliferation of bone marrow-derived mesenchymal stem cells in co-culture.

    PubMed

    Zhang, Fenxi; Lu, Ming; Liu, Hengxing; Ren, Tongming; Miao, Yingying; Wang, Jingjing

    2016-05-01

    Bone marrow-derived mesenchymal stem cells (BMSCs) are a major source for cell transplantation. The proliferative ability of BMSCs is an important determinant of the efficiency of transplant therapy. Sertoli cells are "nurse" cells for development of sperm cells. Our recent study showed that Sertoli cells promoted proliferation of human umbilical cord mesenchymal stem cells (hUCMSCs) in co-culture. Studies by other groups also showed that Sertoli cells promoted growth of endothelial cells and neural stem cells. In this study, we investigated the effect of Sertoli cells on proliferation of BMSCs. Our results showed that Sertoli cells in co-culture significantly enhanced proliferation of BMSCs (P < 0.01). Moreover, co-culture with Sertoli cells also markedly increased mRNA and/or protein expressions of Mdm2, p-Akt and Cyclin D1, and decreased p53 expression in BMSCs (P < 0.01 or < 0.05). These findings indicate that Sertoli cells have the potential to enhance proliferation of BMSCs. PMID:27319049

  15. 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.

  16. CRM1 inhibitor S109 suppresses cell proliferation and induces cell cycle arrest in renal cancer cells.

    PubMed

    Liu, Xuejiao; Chong, Yulong; Liu, Huize; Han, Yan; Niu, Mingshan

    2016-03-01

    Abnormal localization of tumor suppressor proteins is a common feature of renal cancer. Nuclear export of these tumor suppressor proteins is mediated by chromosome region maintenance-1 (CRM1). Here, we investigated the antitumor eff ects of a novel reversible inhibitor of CRM1 on renal cancer cells. We found that S109 inhibits the CRM1-mediated nuclear export of RanBP1 and reduces protein levels of CRM1. Furthermore, the inhibitory eff ect of S109 on CRM1 is reversible. Our data demonstrated that S109 signifi cantly inhibits proliferation and colony formation of renal cancer cells. Cell cycle assay showed that S109 induced G1-phase arrest, followed by the reduction of Cyclin D1 and increased expression of p53 and p21. We also found that S109 induces nuclear accumulation of tumor suppressor proteins, Foxo1 and p27. Most importantly, mutation of CRM1 at Cys528 position abolished the eff ects of S109. Taken together, our results indicate that CRM1 is a therapeutic target in renal cancer and the novel reversible CRM1 inhibitor S109 can act as a promising candidate for renal cancer therapy. PMID:26937212

  17. CCL5 activation of CCR5 regulates cell metabolism to enhance proliferation of breast cancer cells

    PubMed Central

    Gao, Darrin; Rahbar, Ramtin; Fish, Eleanor N.

    2016-01-01

    In earlier studies, we showed that CCL5 enhances proliferation and survival of MCF-7 breast cancer cells in an mTOR-dependent manner and we provided evidence that, for T cells, CCL5 activation of CCR5 results in increased glycolysis and enhanced ATP production. Increases in metabolic activity of cancer cells, specifically increased glycolytic activity and increased expression of glucose transporters, are associated with tumour progression. In this report, we provide evidence that CCL5 enhances the proliferation of human breast cancer cell lines (MDA-MB-231, MCF-7) and mouse mammary tumour cells (MMTV-PyMT), mediated by CCR5 activation. Concomitant with enhanced proliferation we show that CCL5 increases cell surface expression of the glucose transporter GLUT1, and increases glucose uptake and ATP production by these cells. Blocking CCL5-inducible glucose uptake abrogates the enhanced proliferation induced by CCL5. We provide evidence that increased glucose uptake is associated with enhanced glycolysis, as measured by extracellular acidification. Moreover, CCL5 enhances the invasive capacity of these breast cancer cells. Using metabolomics, we demonstrate that the metabolic signature of CCL5-treated primary mouse mammary tumour cells reflects increased anabolic metabolism. The implications are that CCL5–CCR5 interactions in the tumour microenvironment regulate metabolic events, specifically glycolysis, to promote tumour proliferation and invasion. PMID:27335323

  18. Proliferating Cell Nuclear Antigen in Premalignancy and Oral Squamous Cell Carcinoma

    PubMed Central

    Poosarla, Chandrashekar; Ramesh, K.; Gudiseva, Swetha; Bala, Sekar; Sundar, Murali

    2015-01-01

    Introduction Cancer has multifactorial aetiology and is a multistep process involving initiation, promotion and tumour progression. Cellular proliferation is one of the important indicators for the biologic aggressiveness of a malignant lesion. The dysregulated proliferation may be a significant change to determine the potential prognosis of various malignant tumours. Aim The aim of this study was to evaluate the expression of proliferating cell nuclear antigen (PCNA) as an indicator for clinical aggressiveness in oral premalignancy and squamous cell carcinoma. Materials and Methods A total of 50 blocks were taken from the Department of Oral Pathology which was diagnosed previously histopathologically. It comprised of normal oral mucosa (10), dysplasia (10) and grades of oral squamous cell carcinoma (30) of patients between the age group of 40–60 years. From each block, sections of 4 micro metre thicknesses were prepared and placed on poly- L lysine coated slides. These sections were immunohistochemically stained with monoclonal proliferating cell antibody (PC10). The stained slides were evaluated by a single examiner for cell count. Results A comparison between study groups and controls showed a probability value (p-value) < 0.05. Significant increase in the proliferative index from the normal to oral squamous cell carcinoma was noticed. Poorly differentiated squamous cell carcinoma showed maximum proliferative index followed by moderately differentiated, well differentiated squamous cell carcinoma, dysplasia and normal mucosa. Conclusion Present study concluded that PCNA index can be used to assess the proliferation and aggressiveness in dysplasia and different grades oral squamous cell carcinoma. PMID:26266215

  19. CCL5 activation of CCR5 regulates cell metabolism to enhance proliferation of breast cancer cells.

    PubMed

    Gao, Darrin; Rahbar, Ramtin; Fish, Eleanor N

    2016-06-01

    In earlier studies, we showed that CCL5 enhances proliferation and survival of MCF-7 breast cancer cells in an mTOR-dependent manner and we provided evidence that, for T cells, CCL5 activation of CCR5 results in increased glycolysis and enhanced ATP production. Increases in metabolic activity of cancer cells, specifically increased glycolytic activity and increased expression of glucose transporters, are associated with tumour progression. In this report, we provide evidence that CCL5 enhances the proliferation of human breast cancer cell lines (MDA-MB-231, MCF-7) and mouse mammary tumour cells (MMTV-PyMT), mediated by CCR5 activation. Concomitant with enhanced proliferation we show that CCL5 increases cell surface expression of the glucose transporter GLUT1, and increases glucose uptake and ATP production by these cells. Blocking CCL5-inducible glucose uptake abrogates the enhanced proliferation induced by CCL5. We provide evidence that increased glucose uptake is associated with enhanced glycolysis, as measured by extracellular acidification. Moreover, CCL5 enhances the invasive capacity of these breast cancer cells. Using metabolomics, we demonstrate that the metabolic signature of CCL5-treated primary mouse mammary tumour cells reflects increased anabolic metabolism. The implications are that CCL5-CCR5 interactions in the tumour microenvironment regulate metabolic events, specifically glycolysis, to promote tumour proliferation and invasion. PMID:27335323

  20. IRF5 promotes the proliferation of human thyroid cancer cells

    PubMed Central

    2012-01-01

    Background Interferon Regulatory Factor 5 is a transcription factor that regulates the expression of genes involved in the response to viral infection and in the stimulation of the immune system. Moreover, multiple studies have demonstrated that it negatively regulates cell growth and oncogenesis, favoring cell differentiation and apoptosis. Thyroid carcinoma represents 98% of all thyroid malignancies and has shown a steady increase in incidence in both the USA and western European countries. Findings We investigated the expression, localization and function of IRF5 in thyroid cancer cells and found that it is highly expressed in both primary and immortalized thyroid carcinomas but not in normal thyrocytes. IRF5 levels were variably modulated by Interferon alpha but IRF5 only localized in the cytoplasmic compartment, thus failing to induce p21 expression as previously reported in different cell models. Furthermore, ectopic IRF5 increased both the proliferation rate and the clonogenic potential of malignant thyroid cells, protecting them from the cytotoxic effects of DNA-damaging agents. These results were directly attributable to IRF5, as demonstrated by the reduction in colony-forming ability of thyroid cancer cells after IRF5 silencing. An IRF5-dependent induction of endogenous B-Raf observed in all thyroid cancer cells might contribute to these unexpected effects. Conclusions These findings suggest that, in thyroid malignancies, IRF5 displays tumor-promoting rather than tumor-suppressor activities. PMID:22507190

  1. Supporting aspartate biosynthesis is an essential function of respiration in proliferating cells

    PubMed Central

    Sullivan, Lucas B.; Gui, Dan Y.; Hosios, Aaron M.; Bush, Lauren N.; Freinkman, Elizaveta; Vander Heiden, Matthew G.

    2015-01-01

    Summary 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. PMID:26232225

  2. 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. PMID:26232225

  3. CD133-positive cells might be responsible for efficient proliferation of human meningioma cells.

    PubMed

    Tang, Hailiang; Gong, Ye; Mao, Ying; Xie, Qing; Zheng, Mingzhe; Wang, Daijun; Zhu, Hongda; Wang, Xuanchun; Chen, Hong; Chen, Xiancheng; Zhou, Liangfu

    2012-01-01

    Owing to lack of appropriate model systems, investigations of meningioma biology have come to a stop. In this study, we developed a comprehensive digestion method and defined a culture system. Using this method and system, primary meningioma cells in conditioned suspension medium and a hypoxic environment could be amplified in spheres and were passaged for more than ten generations. Meningioma sphere cells were positive for meningioma cell markers and negative for markers of neural cell types. Importantly, we found the cells expressed the stem cell marker, CD133, but not nestin. All of the tumor sphere cell populations showed a slower degree of cell proliferation than that of human glioma cells and fetal neural stem cells (NSCs). Further studies showed that the proliferative rate was positively correlated with CD133 expression. The higher the CD133 expression, the faster the cell proliferation. With the increase in cell generations, the cell proliferation rate gradually slowed down, and CD133 expression also decreased. Single CD133(+) cells rather than CD133(-) cells could form spheres. Thus, the results above indicated that those cells expressing CD133 in spheres might be stem-like cells, which may be responsible for efficient amplification of human meningioma cells. Decreased expression of CD133 may lead to the failure of long-term passaging. PMID:22754374

  4. Signaling pathways implicated in hematopoietic progenitor cell proliferation and differentiation.

    PubMed

    Bugarski, Diana; Krstic, Aleksandra; Mojsilovic, Slavko; Vlaski, Marija; Petakov, Marijana; Jovcic, Gordana; Stojanovic, Nevenka; Milenkovic, Pavle

    2007-01-01

    The objective of this study was to investigate the signal transduction pathways associated with the clonal development of myeloid and erythroid progenitor cells. The contribution of particular signaling molecules of protein tyrosine kinases (PTKs), mitogen-activated protein (MAP) kinase, and PI-3 kinase signaling to the growth of murine bone marrow colony forming unit-granulocyte-macrophage (CFU-GM) and erythroid (burst forming unit-erythroid [BFU-E] and colony forming unit-erythroid [CFU-E]) progenitors was examined in studies performed in the presence or absence of specific signal transduction inhibitors. The results clearly pointed to different signal transducing intermediates that are involved in cell proliferation and differentiation depending on the cell lineage, as well as on the progenitors' maturity. Lineage-specific differences were obtained when chemical inhibitors specific for receptor- or nonreceptor-PTKs, as well as for the main groups of distinctly regulated MAPK cascades, were used because all of these compounds suppressed the growth of erythroid progenitors, with no major effects on myeloid progenitors. At the same time, differential involvement of MEK/extracellular signal-regulated kinase (ERK) MAPK transduction pathway was observed in the proliferation and/or differentiation of early, BFU-E, and late, CFU-E, erythroid progenitor cells. The results also demonstrated that phosphatydylinositol (PI)-3 kinase and nuclear factor kappaB (NF-kappaB) transcriptional factor were required for maintenance of both myeloid and erythroid progenitor cell function. Overall, the data obtained indicated that committed hematopoietic progenitors express a certain level of constitutive signaling activity that participates in the regulation of normal steady-state hematopoiesis and point to the importance of evaluating the impact of signal transduction inhibitors on normal bone marrow when used as potential therapeutic agents. PMID:17202596

  5. Peroxisome proliferator-activated receptor-gamma ligands inhibit proliferation and induce apoptosis in mantle cell lymphoma.

    PubMed

    Eucker, Jan; Sterz, Jan; Krebbel, Holger; Zavrski, Ivana; Kaiser, Martin; Zang, Chuanbing; Heider, Ulrike; Jakob, Christian; Elstner, Elena; Sezer, Orhan

    2006-08-01

    Peroxisome proliferator-activated receptor-gamma, a nuclear receptor and transcription factor, and its natural and synthetic ligands have become a focus of novel approaches to induction of apoptosis in solid tumors and hematologic malignancies, including malignant B-lineage cells. The effect on mantle cell lymphoma, a subtype with dismal prognosis, has not yet been analyzed. We investigated the effect of 15-deoxy-delta-12,14-prostaglandin J2 (15d-PGJ2), pioglitazone (PGZ) or rosiglitazone (RGZ) on human mantle cell lymphoma cell lines (GRANTA-519, Hbl-2 and JeKo-1). Mantle cell lymphoma cell lines exhibited a high expression of Peroxisome proliferator-activated receptor-gamma protein in Western blot analysis. MTT assays revealed anti-proliferative effects induced by both 15d-PGJ2, the natural activator of Peroxisome proliferator-activated receptor-gamma, and PGZ and RGZ, synthetic Peroxisome proliferator-activated receptor-gamma ligands, in a dose-dependent manner. At a dose of 50 micromol/l, 15d-PGJ2 induced growth inhibition in all cell lines. The anti-proliferative effect of PGZ and RGZ was slightly lower. Induction of apoptosis was indicated by annexin V staining. At a dose of 50 micromol/l, 15d-PGJ2 led to apoptosis in all cell lines (87-99%) after 48 h of incubation. Again, the apoptotic effect with thiazolidinediones was slightly lower at the same dose level. This is the first study evaluating Peroxisome proliferator-activated receptor-gamma expression and its therapeutic implications in human mantle cell lymphoma cells. Thiazolidinediones comprise anti-lymphoma activity in vitro and should be further explored for the treatment of mantle cell lymphoma. PMID:16926626

  6. Functional abnormalities of heparan sulfate in mucopolysaccharidosis-I are associated with defective biologic activity of FGF-2 on human multipotent progenitor cells.

    PubMed

    Pan, Chendong; Nelson, Matthew S; Reyes, Morayma; Koodie, Lisa; Brazil, Joseph J; Stephenson, Elliot J; Zhao, Robert C; Peters, Charles; Selleck, Scott B; Stringer, Sally E; Gupta, Pankaj

    2005-09-15

    In mucopolysaccharidosis-I (MPS-I), alpha-L-iduronidase deficiency leads to progressive heparan sulfate (HS) and dermatan sulfate (DS) glycosaminoglycan (GAG) accumulation. The functional consequences of these accumulated molecules are unknown. HS critically influences tissue morphogenesis by binding to and modulating the activity of several cytokines (eg, fibroblast growth factors [FGFs]) involved in developmental patterning. We recently isolated a multipotent progenitor cell from postnatal human bone marrow, which differentiates into cells of all 3 embryonic lineages. The availability of multipotent progenitor cells from healthy volunteers and patients with MPS-I (Hurler syndrome) provides a unique opportunity to directly examine the functional effects of abnormal HS on cytokine-mediated stem-cell proliferation and survival. We demonstrate here that abnormally sulfated HS in Hurler multipotent progenitor cells perturb critical FGF-2-FGFR1-HS interactions, resulting in defective FGF-2-induced proliferation and survival of Hurler multipotent progenitor cells. Both the mitogenic and survival-promoting activities of FGF-2 were restored by substitution of Hurler HS by normal HS. This perturbation of critical HS-cytokine receptor interactions may represent a mechanism by which accumulated HS contributes to the developmental pathophysiology of Hurler syndrome. Similar mechanisms may operate in the pathogenesis of other diseases where structurally abnormal GAGs accumulate. PMID:15947088

  7. 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. PMID:27150157

  8. Amlodipine inhibits cell proliferation via PKD1-related pathway

    SciTech Connect

    Ohba, Takayoshi; Watanabe, Hiroyuki; Murakami, Manabu; Radovanovic, Milena; Iino, Kenji; Ishida, Masaru; Tosa, Shinya; Ono, Kyoichi; Ito, Hiroshi

    2008-05-02

    Human coronary artery smooth muscle cell (hCASMC) proliferation is involved in the progression of coronary artery disease. Amlodipine, a widely used antihypertensive drug, exerts antiproliferative effects by increasing the expression of p21{sup (Waf1/Cip1)}. Polycystic kidney disease 1 (PKD1) is also involved in cell cycle inhibition via p21{sup (Waf1/Cip1)} up-regulation. We clarified the involvement of PKD1-related signaling on hCASMCs. Cultured hCASMCs, which constitutively express PKD1, were stimulated with 5% serum. Amlodipine increased p21{sup (Waf1/Cip1)} expression in a dose- and time-dependent manner, resulting in reduced hCASMC proliferation. The inhibitory effect of amlodipine was mimicked by overexpression of PKD1 and was reversed by a dominant-negative version of PKD1 (R4227X). Immunoblot analysis showed that phosphorylated JAK2 was increased by amlodipine treatment or PKD1 overexpression. A luciferase assay revealed that the overexpression of PKD1 induced STAT1 enhancer activity. These data suggest that PKD1 contributes to the antiproliferative effect of amlodipine on hCASMCs via JAK/STAT signaling and p21{sup (Waf1/Cip1)} up-regulation.

  9. 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.

  10. 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.

  11. 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

  12. Proliferating cell nuclear antigen (PCNA) : ringmaster of the genome.

    SciTech Connect

    Paunesku, T.; Mittal, S.; Protic, M.; Oryhon, J.; Korolev, S. V.; Joachimiak, A.; Woloschak, G. E.; Biosciences Division

    2001-10-01

    Proliferating cell nuclear antigen (PCNA) protein is one of the central molecules responsible for decisions of life and death of the cell. The PCNA gene is induced by p53, while PCNA protein interacts with p53-controlled proteins Gadd45, MyD118, CR6 and, most importantly, p21, in the process of deciding cell fate. If PCNA protein is present in abundance in the cell in the absence of p53, DNA replication occurs. On the other hand, if PCNA protein levels are high in the cell in the presence of p53, DNA repair takes place. If PCNA is rendered non-functional or is absent or present in low quantities in the cell, apoptosis occurs. The evolution from prokaryotes to eukaryotes involved a change of function of PCNA from a 'simple' sliding clamp protein of the DNA polymerase complex to an executive molecule controlling critical cellular decision pathways. The evolution of multicellular organisms led to the development of multicellular processes such as differentiation, senescence and apoptosis. PCNA, already an essential molecule in the life of single cellular organisms, then became a protein critical for the survival of multicellular organisms.

  13. 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.

  14. 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

  15. Effects of LG268 on Cell Proliferation and Apoptosis of NB4 Cells

    PubMed Central

    Xu, Ting; Zhong, Liang; Gan, Liu-Gen; Xiao, Chun-Lan; Shan, Zhi-Ling; Yang, Rong; Song, Hao; Li, Liu; Liu, Bei-Zhong

    2016-01-01

    Aims: To investigate the effect of LG100268 (LG268) on cell proliferation and apoptosis in NB4 cells. Methods: NB4 cells were treated with LG268 for 24 h or 48 h. The effect of LG268 on cell proliferation was assessed by the CCK-8 assay and colony-forming assay. Apoptosis and cell cycle were evaluated by flow cytometry. The protein expression levels of Survivin, PARP, c-Myc, cyclin D1, ERK, p-ERK, p38 MAPK, and p- p38 MAPK were detected by western blot. Results: We found that LG268 inhibited the proliferation of NB4 cells in a dose-dependent manner. Flow cytometry analysis showed that LG268 accelerated apoptosis in NB4 cells in a time- dependent manner and that LG268 treatment led to cell cycle arrest at G0/G1 phase. Moreover, LG268 significantly decreased the protein levels of Survivin, c-Myc, and cyclinD1. Cleaved PARP was observed in the LG268 treatment group but not in the control group. In addition, LG268 increased the phosphorylation level of p38 MAPK and decreased the phosphorylation level of ERK. Conclusions: LG268 inhibited cell proliferation and promoted cell apoptosis in NB4 cells. PMID:27429588

  16. 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. PMID:26842566

  17. Crocin inhibits cell proliferation and enhances cisplatin and pemetrexed chemosensitivity in lung cancer cells

    PubMed Central

    Chen, Shuangshuang; Zhao, Shuang; Wang, Xinxing; Zhang, Luo; Jiang, Enze; Gu, Yuan; Shangguan, Anna Junjie; Zhao, Hong

    2015-01-01

    Background Crocin is the major constituent of saffron, a naturally derived Chinese medicine obtained from the dried stigma of the Crocus sativus flower. It has a variety of pharmacological effects, including anti-oxidative, immunity enhancement, and anti-tumorigenic properties; however, the molecular mechanisms underlying these effects remain unknown. Methods To investigate the effects of crocin on proliferation and apoptosis of lung adenocarcinoma cells, lung adenocarcinoma cell lines, A549 and SPC-A1, were treated with crocin at different dosages. Cell morphological changes were observed by light microscopy. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to detect the inhibitory effect of crocin on cell proliferation and sensitivity to chemotherapeutic drugs. Flow cytometry was used to characterize cell apoptosis and cell cycle profiles. Reverse transcription-polymerase chain reaction was used to detect mRNA levels of apoptosis-related genes. Results Crocin inhibited cell proliferation and induced apoptosis in A549 and SPC-A1 cells in a concentration-dependent manner, accompanied with an increase of G0/G1 arrest. Crocin significantly increased the mRNA levels of both p53 and B-cell lymphoma 2-associated X protein (Bax), while decreasing B-cell lymphoma 2 (Bcl-2) mRNA expressions. In addition, crocin combined with either cisplatin or pemetrexed showed additive effects on cell proliferation in two lung cancer cell lines. Conclusions Crocin significantly suppressed the proliferation of human lung adenocarcinoma cells and enhanced the chemo sensitivity of these cells to both cisplatin and pemetrexed. The actions of molecular mechanism could be through the induction of cell cycle arrest and apoptosis by p53 and Bax up-regulation but Bcl-2 down-regulation. PMID:26798587

  18. Abnormal Interactions between Perifollicular Mast Cells and CD8+ T-Cells May Contribute to the Pathogenesis of Alopecia Areata

    PubMed Central

    Bertolini, Marta; Zilio, Federica; Rossi, Alfredo; Gilhar, Amos; Keren, Aviad; Meyer, Katja C.; Wang, Eddy; Funk, Wolfgang; McElwee, Kevin; Paus, Ralf

    2014-01-01

    Alopecia areata (AA) is a CD8+ T-cell dependent autoimmune disease of the hair follicle (HF) in which the collapse of HF immune privilege (IP) plays a key role. Mast cells (MCs) are crucial immunomodulatory cells implicated in the regulation of T cell-dependent immunity, IP, and hair growth. Therefore, we explored the role of MCs in AA pathogenesis, focusing on MC interactions with CD8+ T-cells in vivo, in both human and mouse skin with AA lesions. Quantitative (immuno-)histomorphometry revealed that the number, degranulation and proliferation of perifollicular MCs are significantly increased in human AA lesions compared to healthy or non-lesional control skin, most prominently in subacute AA. In AA patients, perifollicular MCs showed decreased TGFβ1 and IL-10 but increased tryptase immunoreactivity, suggesting that MCs switch from an immuno-inhibitory to a pro-inflammatory phenotype. This concept was supported by a decreased number of IL-10+ and PD-L1+ MCs, while OX40L+, CD30L+, 4–1BBL+ or ICAM-1+ MCs were increased in AA. Lesional AA-HFs also displayed significantly more peri- and intrafollicular- CD8+ T-cells as well as more physical MC/CD8+ T-cell contacts than healthy or non-lesional human control skin. During the interaction with CD8+ T-cells, AA MCs prominently expressed MHC class I and OX40L, and sometimes 4–1BBL or ICAM-1, suggesting that MC may present autoantigens to CD8+ T-cells and/or co-stimulatory signals. Abnormal MC numbers, activities, and interactions with CD8+ T-cells were also seen in the grafted C3H/HeJ mouse model of AA and in a new humanized mouse model for AA. These phenomenological in vivo data suggest the novel AA pathobiology concept that perifollicular MCs are skewed towards pro-inflammatory activities that facilitate cross-talk with CD8+ T-cells in this disease, thus contributing to triggering HF-IP collapse in AA. If confirmed, MCs and their CD8+ T-cell interactions could become a promising new therapeutic target in the future

  19. SRCIN1 Suppressed Osteosarcoma Cell Proliferation and Invasion.

    PubMed

    Wang, Peng; Wang, Hu; Li, Xiaotao; Liu, Ying; Zhao, Chengbin; Zhu, Daling

    2016-01-01

    SRCIN1 (SRC kinase signalling inhibitor 1) is a new tumor suppressor gene. Previous studies showed that SRCIN1 played a tumor suppressor role in the development of lung cancer and breast cancer. However, the role of SRCIN1 in osteosarcoma is still unknown. In this study, we demonstrated that SRCIN1 was downregulated in osteosarcoma cell lines compared with osteoblastic cell line. Moreover, SRCIN1 was downregulated in osteosarcoma tissues compared with the adjacent tissues. Further investigation revealed that overexpression of SRCIN1 inhibited the osteosarcoma cell line MG-63 proliferation. This effect was confirmed by measuring the ki-67 and PCNA expression. SRCIN1 overexpression promoted E-cadherin expression and suppressed N-cadherin, Vimentin and Snail expression, suggesting that SRCIN1 overexpression inhibited EMT of the osteosarcoma cell. In addition, ectopic expression of SRCIN1 inhibited the MG-63 cell colony formation and invasion. These data suggested that SRCIN1 acted as a tumor suppressor gene in the development of osteosarcoma. PMID:27513473

  20. SRCIN1 Suppressed Osteosarcoma Cell Proliferation and Invasion

    PubMed Central

    Wang, Peng; Wang, Hu; Li, Xiaotao; Liu, Ying; Zhao, Chengbin; Zhu, Daling

    2016-01-01

    SRCIN1 (SRC kinase signalling inhibitor 1) is a new tumor suppressor gene. Previous studies showed that SRCIN1 played a tumor suppressor role in the development of lung cancer and breast cancer. However, the role of SRCIN1 in osteosarcoma is still unknown. In this study, we demonstrated that SRCIN1 was downregulated in osteosarcoma cell lines compared with osteoblastic cell line. Moreover, SRCIN1 was downregulated in osteosarcoma tissues compared with the adjacent tissues. Further investigation revealed that overexpression of SRCIN1 inhibited the osteosarcoma cell line MG-63 proliferation. This effect was confirmed by measuring the ki-67 and PCNA expression. SRCIN1 overexpression promoted E-cadherin expression and suppressed N-cadherin, Vimentin and Snail expression, suggesting that SRCIN1 overexpression inhibited EMT of the osteosarcoma cell. In addition, ectopic expression of SRCIN1 inhibited the MG-63 cell colony formation and invasion. These data suggested that SRCIN1 acted as a tumor suppressor gene in the development of osteosarcoma. PMID:27513473

  1. Paclitaxel Impairs Adipose Stem Cell Proliferation and Differentiation

    PubMed Central

    Choron, Rachel L.; Chang, Shaohua; Khan, Sophia; Villalobos, Miguel A.; Zhang, Ping; Carpenter, Jeffrey P.; Tulenko, Thomas N.; Liu, Yuan

    2015-01-01

    BACKGROUND Cancer patients with chemotherapy-induced immunosuppression have poor surgical site wound healing. Prior literature supports the use of human adipose-derived stem cell (hASC) lipoinjection to improve wound healing. It has been established multipotent hASCs facilitate neovascularization, accelerated epithelialization, and wound closure in animal models. While hASC wound therapy may benefit surgical cancer patients, the chemotherapeutic effects on hASCs are unknown. We hypothesized Paclitaxel, a chemotherapeutic agent, impairs hASC growth, multipotency, and induces apoptosis. METHODS hASCs were isolated and harvested from consented, chemotherapy and radiation naïve patients. Growth curves, MTT, and EdU assays measured cytotoxicity and proliferation. Oil-Red-O stain, Alazarin-Red stain, Matrigel tube-formation assay, and qPCR analyzed hASC differentiation. Annexin V assay measured apoptosis. Immunostaining and Western blot determined TNF-α expression. RESULTS hASCs were selectively more sensitive to Paclitaxel (0.01μM–30μM) than fibroblasts (p<0.05). After 12 days, Paclitaxel caused hASC growth arrest whereas control hASCs proliferated (p=0.006). Paclitaxel caused an 80.6% reduction in new DNA synthesis (p<0.001). Paclitaxel severely inhibited endothelial differentiation and capillary-like tube formation. Differentiation markers LPL (adipogenic), alkaline phosphatase (osteogenic), CD31 and vWF (endothelial) were significantly decreased (all: p<0.05) confirming Paclitaxel impaired differentiation. Paclitaxel was also found to induce apoptosis and TNF-α was up-regulated in Paclitaxel-treated hASCs (p<0.001). CONCLUSION Paclitaxel is more cytotoxic to hASCs than fibroblasts. Paclitaxel inhibits hASC proliferation, differentiation, and induces apoptosis, possibly through the TNF-α pathway. Paclitaxel’s severe inhibition of endothelial differentiation indicates neovascularization disruption, possibly causing poor wound healing in cancer patients

  2. Down-Regulation of NDUFB9 Promotes Breast Cancer Cell Proliferation, Metastasis by Mediating Mitochondrial Metabolism

    PubMed Central

    Gao, Shui-Ping; Jiang, Hong-Lin; Hu, Xin; Jin, Wei

    2015-01-01

    Despite advances in basic and clinical research, metastasis remains the leading cause of death in breast cancer patients. Genetic abnormalities in mitochondria, including mutations affecting complex I and oxidative phosphorylation, are found in breast cancers and might facilitate metastasis. Genes encoding complex I components have significant breast cancer prognostic value. In this study, we used quantitative proteomic analyses to compare a highly metastatic cancer cell line and a parental breast cancer cell line; and observed that NDUFB9, an accessory subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (complex I), was down-regulated in highly metastatic breast cancer cells. Furthermore, we demonstrated that loss of NDUFB9 promotes MDA-MB-231 cells proliferation, migration, and invasion because of elevated levels of mtROS, disturbance of the NAD+/NADH balance, and depletion of mtDNA. We also showed that, the Akt/mTOR/p70S6K signaling pathway and EMT might be involved in this mechanism. Thus, our findings contribute novel data to support the hypothesis that misregulation of mitochondrial complex I NADH dehydrogenase activity can profoundly enhance the aggressiveness of human breast cancer cells, suggesting that complex I deficiency is a potential and important biomarker for further basic research or clinical application. PMID:26641458

  3. Down-Regulation of NDUFB9 Promotes Breast Cancer Cell Proliferation, Metastasis by Mediating Mitochondrial Metabolism.

    PubMed

    Li, Liang-Dong; Sun, He-Fen; Liu, Xue-Xiao; Gao, Shui-Ping; Jiang, Hong-Lin; Hu, Xin; Jin, Wei

    2015-01-01

    Despite advances in basic and clinical research, metastasis remains the leading cause of death in breast cancer patients. Genetic abnormalities in mitochondria, including mutations affecting complex I and oxidative phosphorylation, are found in breast cancers and might facilitate metastasis. Genes encoding complex I components have significant breast cancer prognostic value. In this study, we used quantitative proteomic analyses to compare a highly metastatic cancer cell line and a parental breast cancer cell line; and observed that NDUFB9, an accessory subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (complex I), was down-regulated in highly metastatic breast cancer cells. Furthermore, we demonstrated that loss of NDUFB9 promotes MDA-MB-231 cells proliferation, migration, and invasion because of elevated levels of mtROS, disturbance of the NAD+/NADH balance, and depletion of mtDNA. We also showed that, the Akt/mTOR/p70S6K signaling pathway and EMT might be involved in this mechanism. Thus, our findings contribute novel data to support the hypothesis that misregulation of mitochondrial complex I NADH dehydrogenase activity can profoundly enhance the aggressiveness of human breast cancer cells, suggesting that complex I deficiency is a potential and important biomarker for further basic research or clinical application. PMID:26641458

  4. 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.

  5. Establishment and Characterization of Human Germline Stem Cell Line with Unlimited Proliferation Potentials and no Tumor Formation.

    PubMed

    Hou, Jingmei; Niu, Minghui; Liu, Linhong; Zhu, Zijue; Wang, Xiaobo; Sun, Min; Yuan, Qingqing; Yang, Shi; Zeng, Wenxian; Liu, Yang; Li, Zheng; He, Zuping

    2015-01-01

    Spermatogonial stem cells (SSCs) have significant applications in both reproductive and regenerative medicine. However, primary human SSCs are very rare, and a human SSC line has not yet been available. In this study, we have for the first time reported a stable human SSC line by stably expressing human SV40 large T antigen. RT-PCR, immunocytochemistry, and Western blots revealed that this cell line was positive for a number of human spermatogonial and SSC hallmarks, including VASA, DAZL, MAGEA4, GFRA1, RET, UCHL1, GPR125, PLZF and THY1, suggesting that these cells are human SSCs phenotypically. Proliferation analysis showed that the cell line could be expanded with significant increases of cells for 1.5 years, and high levels of PCNA, UCHL1 and SV40 were maintained for long-term culture. Transplantation assay indicated that human SSC line was able to colonize and proliferate in vivo in the recipient mice. Neither Y chromosome microdeletions of numerous genes nor tumor formation was observed in human SSC line although there was abnormal karyotype in this cell line. Collectively, we have established a human SSC line with unlimited proliferation potentials and no tumorgenesis, which could provide an abundant source of human SSCs for their mechanistic studies and translational medicine. PMID:26585066

  6. Establishment and Characterization of Human Germline Stem Cell Line with Unlimited Proliferation Potentials and no Tumor Formation

    PubMed Central

    Hou, Jingmei; Niu, Minghui; Liu, Linhong; Zhu, Zijue; Wang, Xiaobo; Sun, Min; Yuan, Qingqing; Yang, Shi; Zeng, Wenxian; Liu, Yang; Li, Zheng; He, Zuping

    2015-01-01

    Spermatogonial stem cells (SSCs) have significant applications in both reproductive and regenerative medicine. However, primary human SSCs are very rare, and a human SSC line has not yet been available. In this study, we have for the first time reported a stable human SSC line by stably expressing human SV40 large T antigen. RT-PCR, immunocytochemistry, and Western blots revealed that this cell line was positive for a number of human spermatogonial and SSC hallmarks, including VASA, DAZL, MAGEA4, GFRA1, RET, UCHL1, GPR125, PLZF and THY1, suggesting that these cells are human SSCs phenotypically. Proliferation analysis showed that the cell line could be expanded with significant increases of cells for 1.5 years, and high levels of PCNA, UCHL1 and SV40 were maintained for long-term culture. Transplantation assay indicated that human SSC line was able to colonize and proliferate in vivo in the recipient mice. Neither Y chromosome microdeletions of numerous genes nor tumor formation was observed in human SSC line although there was abnormal karyotype in this cell line. Collectively, we have established a human SSC line with unlimited proliferation potentials and no tumorgenesis, which could provide an abundant source of human SSCs for their mechanistic studies and translational medicine. PMID:26585066

  7. 5-Azacytidine suppresses the proliferation of pancreatic cancer cells by inhibiting the Wnt/β-catenin signaling pathway.

    PubMed

    Zhang, H; Zhou, W C; Li, X; Meng, W B; Zhang, L; Zhu, X L; Zhu, K X; Bai, Z T; Yan, J; Liu, T; Xu, X C; Li, Y M

    2014-01-01

    5-Azacytidine has been shown to be an effective anti-pancreatic cancer drug, but the mechanism remains unknown. In the current study, we explored the effect of 5-azacytidine on abnormal activation of the Wnt-β-catenin signaling pathway in pancreatic cancer cells. The human pancreatic cancer cell line Bxpc-3 was treated with different concentrations of 5-azacytidine for various times. The proliferation and early apoptosis of the cells were evaluated using the CCK8 method and flow cytometry, respectively. mRNA and protein expression of β-catenin, c-myc, and cyclinD1 were detected using real-time fluorescent quantitative polymerase chain reaction and Western blot analysis, respectively. The proliferation of Bxpc-3 cells was suppressed by 5-azacytidine. The early apoptosis of the cells was significantly enhanced over time and with increasing drug concentrations. The expression of β-catenin, c-myc, and cyclinD1 were down-regulated, showing significant differences between different concentrations and treatment times (P < 0.05). 5-Azacytidine suppressed the proliferation of pancreatic cancer cells by inhibiting the Wnt/β-catenin signaling pathway, particularly the expression of β-catenin, c-myc, and cyclinD1. This study may provide a new potential strategy for diagnosing and treating pancreatic cancer. PMID:25061731

  8. GRP78 is required for cell proliferation and protection from apoptosis in chicken embryo fibroblast cells.

    PubMed

    Jeon, M; Choi, H; Lee, S I; Kim, J S; Park, M; Kim, K; Lee, S; Byun, S J

    2016-05-01

    Chicken serum has been suggested as a supplement to promote chicken cell proliferation and development. However, the molecular mechanisms by which chicken serum stimulates chicken cell proliferation remain unknown. Here, we evaluated the effects of chicken serum supplementation on chicken embryo fibroblast (CEF) and DF-1 cell proliferation. We also sought to elucidate the molecular pathways involved in mediating the effects of chicken serum on fibroblasts and DF-1 cells by overexpression of chicken 78 kDa glucose-regulated protein (chGRP78), which is important for cell growth and the prevention of apoptosis. Our data demonstrated that the addition of 5% chicken serum significantly enhanced fibroblast proliferation. Moreover, knockdown of chGRP78 using siRNA decreased fibroblast proliferation and increased apoptosis. Based on these results, we suggest that the chGRP78-mediated signaling pathway plays a critical role in chicken serum-stimulated fibroblast survival and anti-apoptosis. Therefore, our findings have important implications for the maintenance of chicken fibroblast cells through the inhibition of apoptosis and may lead to the development of new treatments for avian disease. PMID:26944959

  9. Chicken stem cell factor enhances primordial germ cell proliferation cooperatively with fibroblast growth factor 2

    PubMed Central

    MIYAHARA, Daichi; OISHI, Isao; MAKINO, Ryuichi; KURUMISAWA, Nozomi; NAKAYA, Ryuma; ONO, Tamao; KAGAMI, Hiroshi; TAGAMI, Takahiro

    2015-01-01

    An in vitro culture system of chicken primordial germ cells (PGCs) has been recently developed, but the growth factor involved in the proliferation of PGCs is largely unknown. In the present study, we investigated the growth effects of chicken stem cell factor (chSCF) on the in vitro proliferation of chicken PGCs. We established two feeder cell lines (buffalo rat liver cells; BRL cells) that stably express the putative secreted form of chSCF (chSCF1-BRL) and membrane bound form of chSCF (chSCF2-BRL). Cultured PGC lines were incubated on chSCF1 or chSCF2-BRL feeder cells with fibroblast growth factor 2 (FGF2), and growth effects of each chSCF isoform were investigated. The in vitro proliferation rate of the PGCs cultured on chSCF2-BRL at 20 days of culture was more than threefold higher than those cultured on chSCF1-BRL cells and more than fivefold higher than those cultured on normal BRL cells. Thus, use of chSCF2-BRL feeder layer was effective for in vitro proliferation of chicken PGCs. However, the acceleration of PGC proliferation on chSCF2-BRL was not observed without FGF2, suggesting that chSCF2 would act as a proliferation co-factor of FGF2. We transferred the PGCs cultured on chSCF2-BRL cells to recipient embryos, generated germline chimeric chickens and assessed the germline competency of cultured PGCs by progeny test. Donor-derived progenies were obtained, and the frequency of germline transmission was 3.39%. The results of this study demonstrate that chSCF2 induces hyperproliferation of chicken PGCs retaining germline competency in vitro in cooperation with FGF2. PMID:26727404

  10. Extracellular Calcium Has Multiple Targets to Control Cell Proliferation.

    PubMed

    Capiod, Thierry

    2016-01-01

    Calcium channels and the two G-protein coupled receptors sensing extracellular calcium, calcium-sensing receptor (CaSR) and GPRC6a, are the two main means by which extracellular calcium can signal to cells and regulate many cellular processes including cell proliferation, migration and invasion of tumoral cells. Many intracellular signaling pathways are sensitive to cytosolic calcium rises and conversely intracellular signaling pathways can modulate calcium channel expression and activity. Calcium channels are undoubtedly involved in the former while the CaSR and GPRC6a are most likely to interfere with the latter. As for neurotransmitters, calcium ions use plasma membrane channels and GPCR to trigger cytosolic free calcium concentration rises and intracellular signaling and regulatory pathways activation. Calcium sensing GPCR, CaSR and GPRC6a, allow a supplemental degree of control and as for metabotropic receptors, they not only modulate calcium channel expression but they may also control calcium-dependent K+ channels. The multiplicity of intracellular signaling pathways involved, their sensitivity to local and global intracellular calcium increase and to CaSR and GPRC6a stimulation, the presence of membrane signalplex, all this confers the cells the plasticity they need to convert the effects of extracellular calcium into complex physiological responses and therefore determine their fate. PMID:27161228

  11. The nucleolus: a paradigm for cell proliferation and aging.

    PubMed

    Comai, L

    1999-12-01

    The nucleolus is the cellular site of ribosome biosynthesis. At this site, active ribosomal DNA (rDNA) genes are rapidly transcribed by RNA polymerase I (pol I) molecules. Recent advances in our understanding of the pol I transcription system have indicated that regulation of ribosomal RNA (rRNA) synthesis is a critical factor in cell growth. Importantly, the same signaling networks that control cell growth and proliferation and are deregulated in cancer appear to control pol I transcription. Therefore, the study of the biochemical basis for growth regulation of pol I transcription can provide basic information about the nuclear signaling network. Hopefully, this information may facilitate the search for drugs that can inhibit the growth of tumor cells by blocking pol I activation. In addition to its function in ribosome biogenesis, recent studies have revealed the prominent role of the nucleolus in cell senescence. These findings have stimulated a new wave of research on the functional relationship between the nucleolus and aging. The aim of this review is to provide an overview of some current topics in the area of nucleolus biology, and it has been written for a general readership. PMID:10585627

  12. YM155 suppresses cell proliferation and induces cell death in human adult T-cell leukemia/lymphoma cells.

    PubMed

    Sasaki, Ryousei; Ito, Shigeki; Asahi, Maki; Ishida, Yoji

    2015-12-01

    Adult T-cell leukemia (ATL) is an aggressive malignancy of peripheral T cells infected with human T-cell leukemia virus type 1 (HTLV-1). The prognosis of patients with aggressive ATL remains poor because ATL cells acquire resistance to conventional cytotoxic agents. Therefore, development of novel agents is urgently needed. We examined the effects of YM155, sepantronium bromide, on cell proliferation and survival of ATL or HTLV-1-infected T-cell lines, S1T, MT-1, and MT-2. We found that YM155 suppressed cell proliferation in these cells and induced cell death in S1T and MT-1 cells. Both real-time quantitative polymerase chain reaction and immunoblot analyses showed suppression of survivin expression in S1T, MT-1, and MT-2 cells. In addition, we observed the cleavage of caspase-3 and poly(ADP-ribose) polymerase in YM155-treated S1T and MT-1 cells, indicating that YM155 induces caspase-dependent apoptosis in these cells. To clarify the mechanism of drug tolerance of MT-2 cells in terms of YM155-induced cell death, we examined intracellular signaling status in these cells. We found that STAT3, STAT5, and AKT were constitutively phosphorylated in MT-2 cells but not in S1T and MT-1 cells. Treatment with YM155 combined with the STAT3 inhibitor S3I-201 significantly suppressed cell proliferation compared to that with either YM155 or S3I-201 in MT-2 cells, indicating that STAT3 may play a role in tolerance of MT-2 cells to YM155 and that STAT3 may therefore be a therapeutic target for YM155-resistant ATL cells. These results suggest that YM155 presents potent antiproliferative and apoptotic effects via suppression of survivin in ATL cells in which STAT3 is not constitutively phosphorylated. YM155 merits further investigation as a potential chemotherapeutic agent for ATL. PMID:26547260

  13. Mesenchymal stem cells induce epithelial proliferation within the inflamed stomach.

    PubMed

    Donnelly, Jessica M; Engevik, Amy; Feng, Rui; Xiao, Chang; Boivin, Gregory P; Li, Jing; Houghton, JeanMarie; Zavros, Yana

    2014-06-15

    Bone marrow-derived mesenchymal stem cells (MSCs) sustain cancer cells by creating a microenvironment favorable for tumor growth. In particular, MSCs have been implicated in gastric cancer development. There is extensive evidence suggesting that Hedgehog signaling regulates tumor growth. However, very little is known regarding the precise roles of Hedgehog signaling and MSCs in tumor development within the stomach. The current study tests that hypothesis that Sonic Hedgehog (Shh), secreted from MSCs, provides a proliferative stimulus for the gastric epithelium in the presence of inflammation. Red fluorescent protein-expressing MSCs transformed in vitro (stMSCs) were transduced with lentiviral constructs containing a vector control (stMSC(vect)) or short hairpin RNA (shRNA) targeting the Shh gene (stMSC(ShhKO)). Gastric submucosal transplantation of wild-type MSCs (wtMSCs), wild-type MSCs overexpressing Shh (wtMSC(Shh)), stMSC(vect), or stMSC(ShhKO) cells in C57BL/6 control (BL/6) or gastrin-deficient (GKO) mice was performed and mice analyzed 30 and 60 days posttransplantation. Compared with BL/6 mice transplanted with wtMSC(Shh) and stMSC(vect) cells, inflamed GKO mice developed aggressive gastric tumors. Tumor development was not observed in mouse stomachs transplanted with wtMSC or stMSC(ShhKO) cells. Compared with stMSC(ShhKO)-transplanted mice, within the inflamed GKO mouse stomach, Shh-expressing stMSC(vect)- and wtMSC(Shh)-induced proliferation of CD44-positive cells. CD44-positive cells clustered in gland-like structures within the tumor stroma and were positive for Patched (Ptch) expression. We conclude that Shh, secreted from MSCs, provides a proliferative stimulus for the gastric epithelium that is associated with tumor development, a response that is sustained by chronic inflammation. PMID:24789207

  14. Targeting Homeostatic T Cell Proliferation to Control Beta-Cell Autoimmunity.

    PubMed

    Vignali, Debora; Monti, Paolo

    2016-05-01

    Immunomodulation of the autoreactive T cell response is considered a major strategy to control beta-cell autoimmunity, both in the natural history of type 1 diabetes and in islet transplantation, which can be affected by autoimmunity recurrence. So far, these strategies have had modest results, prompting efforts to define novel cellular and molecular targets to control autoreactive T cell expansion and activation. Novel findings highlighted the important role of the homeostatic cytokine interleukin-7 in inducing proliferation and differentiation of autoreactive T cell clones that causes beta-cell autoimmunity. In this review, we discuss recent evidences and novel findings on the role of IL-7 mediated homeostatic T cell proliferation in the process of beta-cell destruction and evidences of how targeting IL-7 and its receptor could be an innovative and effective strategy to control beta-cell autoimmunity. PMID:26983628

  15. Survivin expression is associated with lens epithelial cell proliferation and fiber cell differentiation

    PubMed Central

    Mansergh, Fiona C.; Boulton, Michael E.; Gunhaga, Lena

    2012-01-01

    Purpose Survivin (Birc5) is the smallest member of the inhibitor of apoptosis (IAP) protein family, which regulates the cell cycle/apoptosis balance. The purpose of this study was to examine Survivin expression in the embryonic chick lens, in chick lens epithelial cell cultures, and in the postnatal mouse lens. Methods Survivin expression was examined using a combination of quantitative real-time polymerase chain reaction, western blotting, and immunocytochemistry. To correlate Survivin expression with the timing of proliferation, we determined the profile of cell proliferation in the developing lens using the cell cycle marker proliferating cell nuclear antigen (PCNA) in quantitative western blotting and immunocytochemistry studies. We also examined the expression of PCNA and the extent of denucleation using terminal deoxynucleotidyl transferase (TdT)-mediated biotin-dUTP nick-end labeling (TUNEL) of lentoids (lens fiber-like cells) during chick lens epithelial cell differentiation in vitro. Results At embryonic day (ED) 4, Survivin immunostaining was present in two pools in lens epithelial cells and fiber cells: cytoplasmic and nuclear. The nuclear staining became more pronounced as the lens epithelial cells differentiated into lens fiber cells. At ED12, Survivin staining was observed in lens fiber cell nuclei containing marginalized chromatin, indicative of early denucleation events. Using western blotting, Survivin expression peaked at ED6, diminishing thereafter. This profile of expression correlated with the events in chick lens epithelial cell cultures: i) increased Survivin expression was associated with an increase in PCNA staining up to day 6 of culture and ii) downregulation of Survivin expression at day 8 of culture was coincident with a dramatic decrease in PCNA staining and an increase in TdT-mediated biotin-dUTP nick-end labeling in lentoids. In early postnatal mouse lenses, Survivin and PCNA were highly expressed and decreased thereafter during

  16. Transient Inhibition of Cell Proliferation does not Compromise Self-Renewal of Mouse Embryonic Stem Cells

    PubMed Central

    Wang, Ruoxing; Guo, Yan-Lin

    2012-01-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. PMID:22705123

  17. Cells, cancer, and rare events: Homeostatic metastability in stochastic nonlinear dynamical models of skin cell proliferation

    NASA Astrophysics Data System (ADS)

    Warren, Patrick B.

    2009-09-01

    A recently proposed model for skin cell proliferation [E. Clayton , Nature (London) 446, 185 (2007)] is extended to incorporate mitotic autoregulation, and hence homeostasis as a fixed point of the dynamics. Unlimited cell proliferation in such a model can be viewed as a model for carcinogenesis. One way in which this can arise is homeostatic metastability, in which the cell populations escape from the homeostatic basin of attraction by a large but rare stochastic fluctuation. Such an event can be viewed as the final step in a multistage model of carcinogenesis. Homeostatic metastability offers a possible explanation for the peculiar epidemiology of lung cancer in ex-smokers.

  18. Shared clonal cytogenetic abnormalities in aberrant mast cells and leukemic myeloid blasts detected by single nucleotide polymorphism microarray-based whole-genome scanning.

    PubMed

    Frederiksen, John K; Shao, Lina; Bixby, Dale L; Ross, Charles W

    2016-04-01

    Systemic mastocytosis (SM) is characterized by a clonal proliferation of aberrant mast cells within extracutaneous sites. In a subset of SM cases, a second associated hematologic non-mast cell disease (AHNMD) is also present, usually of myeloid origin. Polymerase chain reaction and targeted fluorescence in situ hybridization studies have provided evidence that, in at least some cases, the aberrant mast cells are related clonally to the neoplastic cells of the AHNMD. In this work, a single nucleotide polymorphism microarray (SNP-A) was used to characterize the cytogenetics of the aberrant mast cells from a patient with acute myeloid leukemia and concomitant mast cell leukemia associated with a KIT D816A mutation. The results demonstrate the presence of shared cytogenetic abnormalities between the mast cells and myeloid blasts, as well as additional abnormalities within mast cells (copy-neutral loss of heterozygosity) not detectable by routine karyotypic analysis. To our knowledge, this work represents the first application of SNP-A whole-genome scanning to the detection of shared cytogenetic abnormalities between the two components of a case of SM-AHNMD. The findings provide additional evidence of a frequent clonal link between aberrant mast cells and cells of myeloid AHNMDs, and also highlight the importance of direct sequencing for identifying uncommon activating KIT mutations. PMID:26865278

  19. Matrix Metalloproteinase-3 in Odontoblastic Cells Derived from Ips Cells: Unique Proliferation Response as Odontoblastic Cells Derived from ES Cells

    PubMed Central

    Hiyama, Taiki; Ozeki, Nobuaki; Mogi, Makio; Yamaguchi, Hideyuki; Kawai, Rie; Nakata, Kazuhiko; Kondo, Ayami; Nakamura, Hiroshi

    2013-01-01

    We previously reported that matrix metalloproteinase (MMP)-3 accelerates wound healing following dental pulp injury. In addition, we reported that a proinflammatory cytokine mixture (tumor necrosis factor-α, interleukin (IL)-1β and interferon-γ) induced MMP-3 activity in odontoblast-like cells derived from mouse embryonic stem (ES) cells, suggesting that MMP-3 plays a potential unique physiological role in wound healing and regeneration of dental pulp in odontoblast-like cells. In this study, we tested the hypothesis that upregulation of MMP-3 activity by IL-1β promotes proliferation and apoptosis of purified odontoblast-like cells derived from induced pluripotent stem (iPS) and ES cells. Each odontoblast-like cell was isolated and incubated with different concentrations of IL-1β. MMP-3 mRNA and protein expression were assessed using RT-PCR and western blotting, respectively. MMP-3 activity was measured using immunoprecipitation and a fluorescence substrate. Cell proliferation and apoptosis were determined using ELISA for BrdU and DNA fragmentation, respectively. siRNA was used to reduce MMP-3 transcripts in these cells. Treatment with IL-1β increased MMP-3 mRNA and protein levels, and MMP-3 activity in odontoblast-like cells. Cell proliferation was found to markedly increase with no changes in apoptosis. Endogenous tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 were constitutively expressed during all experiments. The exocytosis inhibitor, Exo1, potently suppressed the appearance of MMP-3 in the conditioned medium. Treatment with siRNA against MMP-3 suppressed an IL-1β-induced increase in MMP-3 expression and activity, and also suppressed cell proliferation, but unexpectedly increased apoptosis in these cells (P<0.05). Exogenous MMP-3 was found to induce cell proliferation in odontoblast-like cells derived from iPS cells and ES cells. This siRNA-mediated increase in apoptosis could be reversed with exogenous MMP-3 stimulation (P<0.05). Taken

  20. Folic Acid Supplementation Stimulates Notch Signaling and Cell Proliferation in Embryonic Neural Stem Cells

    PubMed Central

    Liu, Huan; Huang, Guo-wei; Zhang, Xu-mei; Ren, Da-lin; X. Wilson, John

    2010-01-01

    The present study investigated the effect of folic acid supplementation on the Notch signaling pathway and cell proliferation in rat embryonic neural stem cells (NSCs). The NSCs were isolated from E14–16 rat brain and grown as neurospheres in serum-free suspension culture. Individual cultures were assigned to one of 3 treatment groups that differed according to the concentration of folic acid in the medium: Control (baseline folic acid concentration of 4 mg/l), low folic acid supplementation (4 mg/l above baseline, Folate-L) and high folic acid supplementation (40 mg/l above baseline, Folate-H). NSCs were identified by their expression of immunoreactive nestin and proliferating cells by incorporation of 5'bromo-2'deoxyuridine. Cell proliferation was also assessed by methyl thiazolyl tetrazolium assay. Notch signaling was analyzed by real-time PCR and western blot analyses of the expression of Notch1 and hairy and enhancer of split 5 (Hes5). Supplementation of NSCs with folic acid increased the mRNA and protein expression levels of Notch1 and Hes5. Folic acid supplementation also stimulated NSC proliferation dose-dependently. Embryonic NSCs respond to folic acid supplementation with increased Notch signaling and cell proliferation. This mechanism may mediate the effects of folic acid supplementation on neurogenesis in the embryonic nervous system. PMID:20838574

  1. HaCaT cell proliferation influenced by melatonin.

    PubMed

    Hipler, U-C; Fischer, T W; Elsner, P

    2003-01-01

    The hormone melatonin is characterized by numerous pharmacological effects. The influence of melatonin on the growth of the human hair follicle was shown in previous investigations. In the present study, the effects of melatonin were investigated by means of proliferation tests of HaCaT keratinocytes using the [3H]thymidine incorporation, a fluorescence assay with Hoechst dye 33342 and the ATP bioluminescence assay. The aim of the study was to find melatonin concentrations suitable for treatments of the skin and whether there is a cytotoxic effect on HaCaT cells. The different proliferative activity of melatonin depending on its concentration and the time of incubation could be shown in all investigations. PMID:14528062

  2. Analysis of Block of cell proliferation 1 (BOP1) activity in strawberry and Arabidopsis.

    PubMed

    Carvalho, Sofia D; Chatterjee, Mithu; Coleman, Lauren; Clancy, Maureen A; Folta, Kevin M

    2016-04-01

    Block of cell proliferation (BOP) proteins are conserved among eukaryotes, and studies in mammals and yeast have described their role in ribosome biogenesis and cell cycle regulation. A BOP1 orthologue was identified in plants, and loss-of-function analyses in tobacco cells confirmed similar activities. This report characterizes a role for BOP1 activity in planta. Two transgenic plant species were used: the diploid strawberry (Fragaria vesca) and Arabidopsis thaliana. FvBOP1 silencing showed changes in pre-rRNA processing, and demonstrated FvBOP1's role in growth and physiology throughout different stages of plant development. In the strawberry, repression of FvBOP1 activity decreased plant fitness prior to flowering, followed by plant death after the reproductive transition, indicating that BOP1 activity is required for transition back to vegetative growth after flowering. A T-DNA null allele of the AtBOP1 gene is lethal, and a 50% decrease in transcript accumulation is sufficient to cause severe developmental defects linked to defective cell division. The conserved protein BOP1 is essential for viability. Lower transcript levels result in defects in rRNA processing and developmental abnormalities that are consistent with its predicted role in ribosome biogenesis. PMID:26940494

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

    SciTech Connect

    Hogan, Niamh M.; Joyce, Myles R.; Murphy, J. Mary; Barry, Frank P.; O’Brien, Timothy; Kerin, Michael J.; Dwyer, Roisin M.

    2013-06-14

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

  4. Low power laser irradiation stimulates cell proliferation via proliferating cell nuclear antigen and Ki-67 expression during tissue repair

    NASA Astrophysics Data System (ADS)

    Prabhu, Vijendra; Rao, Bola Sadashiva Satish; Mahato, Krishna Kishore

    2015-03-01

    Low power laser irradiation (LPLI) is becoming an increasingly popular and fast growing therapeutic modality in dermatology to treat various ailments without any reported side effects. In the present study an attempt was made to investigate the proliferative potential of red laser light during tissue repair in Swiss albino mice. To this end, full thickness excisional wounds of diameter 15 mm created on mice were exposed to single dose of Helium-Neon laser (632.8 nm; 7 mW; 4.02 mWcm-2; Linear polarization) at 2 Jcm-2 and 10 Jcm-2 along with un-illuminated controls. The granulation tissues from all the respective experimental groups were harvested on day 10 post-wounding following euthanization. Subsequently, tissue regeneration potential of these laser doses under study were evaluated by monitoring proliferating cell nuclear antigen and Ki-67 following the laser treatment and comparing it with the un-illuminated controls. The percentages of Ki-67 or PCNA positive cells were determined by counting positive nuclei (Ki-67/PCNA) and total nuclei in five random fields per tissue sections. Animal wounds treated with single exposure of the 2 Jcm-2 indicated significant elevation in PCNA (P<0.01) and Ki-67 (P<0.05 compared to un-illuminated control and P<0.01 compared to 10 Jcm-2) expression as compared to other tested experimental groups as evidenced by the microscopy results in the study. In summary, the findings of the present study have clearly demonstrated the regulation of cell proliferation by LPLI via PCNA and Ki-67 expression during tissue regeneration.

  5. Fyn kinase genetic ablation causes structural abnormalities in mature retina and defective Müller cell function.

    PubMed

    Chavez-Solano, Marbella; Ibarra-Sanchez, Alfredo; Treviño, Mario; Gonzalez-Espinosa, Claudia; Lamas, Monica

    2016-04-01

    Fyn kinase is widely expressed in neuronal and glial cells of the brain, where it exerts multiple functional roles that affect fundamental physiological processes. The aim of our study was to investigate the, so far unknown, functional role of Fyn in the retina. We report that Fyn is expressed, in vivo, in a subpopulation of Müller glia. We used a mouse model of Fyn genetic ablation and Müller-enriched primary cultures to demonstrate that Fyn deficiency induces morphological alterations in the mature retina, a reduction in the thickness of the outer and inner nuclear layers and alterations in postnatal Müller cell physiology. These include shortening of Müller cell processes, a decrease in cell proliferation, inactivation of the Akt signal transduction pathway, a reduced number of focal adhesions points and decreased adhesion of these cells to the ECM. As abnormalities in Müller cell physiology have been previously associated to a compromised retinal function we evaluated behavioral responses to visual stimulation. Our results associate Fyn deficiency with impaired visual optokinetic responses under scotopic and photopic light conditions. Our study reveals novel roles for Fyn kinase in retinal morphology and Müller cell physiology and suggests that Fyn is required for optimal visual processing. PMID:26808221

  6. Mechanisms of Regulating Cell Topology in Proliferating Epithelia: Impact of Division Plane, Mechanical Forces, and Cell Memory

    PubMed Central

    Li, Yingzi; Naveed, Hammad; Kachalo, Sema; Xu, Lisa X.; Liang, Jie

    2012-01-01

    Regulation of cell growth and cell division has a fundamental role in tissue formation, organ development, and cancer progression. Remarkable similarities in the topological distributions were found in a variety of proliferating epithelia in both animals and plants. At the same time, there are species with significantly varied frequency of hexagonal cells. Moreover, local topology has been shown to be disturbed on the boundary between proliferating and quiescent cells, where cells have fewer sides than natural proliferating epithelia. The mechanisms of regulating these topological changes remain poorly understood. In this study, we use a mechanical model to examine the effects of orientation of division plane, differential proliferation, and mechanical forces on animal epithelial cells. We find that regardless of orientation of division plane, our model can reproduce the commonly observed topological distributions of cells in natural proliferating animal epithelia with the consideration of cell rearrangements. In addition, with different schemes of division plane, we are able to generate different frequency of hexagonal cells, which is consistent with experimental observations. In proliferating cells interfacing quiescent cells, our results show that differential proliferation alone is insufficient to reproduce the local changes in cell topology. Rather, increased tension on the boundary, in conjunction with differential proliferation, can reproduce the observed topological changes. We conclude that both division plane orientation and mechanical forces play important roles in cell topology in animal proliferating epithelia. Moreover, cell memory is also essential for generating specific topological distributions. PMID:22912800

  7. TESTIN Induces Rapid Death and Suppresses Proliferation in Childhood B Acute Lymphoblastic Leukaemia Cells

    PubMed Central

    Weeks, Robert J.; Ludgate, Jackie L.; LeMée, Gwenn; Morison, Ian M.

    2016-01-01

    Background Childhood acute lymphoblastic leukaemia (ALL) is the most common malignancy in children. Despite high cure rates, side effects and late consequences of the intensive treatments are common. Unquestionably, the identification of new therapeutic targets will lead to safer, more effective treatments. We identified TES promoter methylation and transcriptional silencing as a very common molecular abnormality in childhood ALL, irrespective of molecular subtype. The aims of the present study were to demonstrate that TES promoter methylation is aberrant, to determine the effects of TES re-expression in ALL, and to determine if those effects are mediated via TP53 activity. Methods Normal fetal and adult tissue DNA was isolated and TES promoter methylation determined by Sequenom MassARRAY. Quantitative RT-PCR and immunoblot were used to confirm re-expression of TES in ALL cell lines after 5’-aza-2’-deoxycytidine (decitabine) exposure or transfection with TES expression plasmids. The effects of TES re-expression on ALL cells were investigated using standard cell proliferation, cell death and cell cycle assays. Results In this study, we confirm that the TES promoter is unmethylated in normal adult and fetal tissues. We report that decitabine treatment of ALL cell lines results in demethylation of the TES promoter and attendant expression of TES mRNA. Re-expression of TESTIN protein in ALL cells using expression plasmid transfection results in rapid cell death or cell cycle arrest independent of TP53 activity. Conclusions These results suggest that TES is aberrantly methylated in ALL and that re-expression of TESTIN has anti-leukaemia effects which point to novel therapeutic opportunities for childhood ALL. PMID:26985820

  8. Fractional Proliferation: A method to deconvolve cell population dynamics from single-cell data

    PubMed Central

    Tyson, Darren R.; Garbett, Shawn P.; Frick, Peter L.; Quaranta, Vito

    2012-01-01

    We present an integrated method that exploits extended time-lapse automated imaging to quantify dynamics of cell proliferation. Cell counts are fit with a Quiescence-Growth model that estimates rates of cell division, entry into quiescence and death. The model is constrained with rates extracted experimentally from the behavior of tracked single cells over time. We visualize the output of the analysis in Fractional Proliferation graphs, which deconvolve dynamic proliferative responses to perturbations into the relative contributions of dividing, quiescent (non-dividing) and dead cells. The method reveals that the response of “oncogene-addicted” human cancer cells to tyrosine kinase inhibitors is a composite of altered rates of division, death and entry into quiescence, challenging the notion that such cells simply ‘die’ in response to oncogene-targeted therapy. PMID:22886092

  9. Silencing of carboxypeptidase E inhibits cell proliferation, tumorigenicity, and metastasis of osteosarcoma cells

    PubMed Central

    Fan, Shuli; Li, Xu; Li, Leiming; Wang, Liguo; Du, Zhangzhen; Yang, Yan; Zhao, Jiansong; Li, Yan

    2016-01-01

    Carboxypeptidase E (CPE), a prohormone processing enzyme, has been implicated in the progression of multiple malignancies. However, the biological role and molecular mechanisms of CPE in osteosarcoma remain elusive. In this study, we assessed the effects of CPE on cell proliferation, tumorigenicity, migration, and invasion in osteosarcoma. Our results showed that silencing of CPE significantly inhibited cell proliferation, caused cell cycle arrest at G0/G1 phase, decreased the expression levels of cell cycle protein, cyclin D1, and inhibited tumorigenicity in vivo. Additionally, CPE downregulation repressed the migratory and invasive capacities of osteosarcoma cells in vitro. Furthermore, overexpression of CPE-ΔN (a splice variant of CPE) enhanced the cell growth, migration, and invasion of osteosarcoma cells. It is possible that both CPE forms are involved in the tumorigenesis and development of osteosarcoma, and therefore CPE may provide a promising biological target for osteosarcoma therapy. PMID:27274275

  10. Bone morphogenetic protein-4 strongly potentiates growth factor-induced proliferation of mammary epithelial cells

    SciTech Connect

    Montesano, Roberto Sarkoezi, Rita; Schramek, Herbert

    2008-09-12

    Bone morphogenetic proteins (BMPs) are multifunctional cytokines that elicit pleiotropic effects on biological processes such as cell proliferation, cell differentiation and tissue morphogenesis. With respect to cell proliferation, BMPs can exert either mitogenic or anti-mitogenic activities, depending on the target cells and their context. Here, we report that in low-density cultures of immortalized mammary epithelial cells, BMP-4 did not stimulate cell proliferation by itself. However, when added in combination with suboptimal concentrations of fibroblast growth factor (FGF)-2, FGF-7, FGF-10, epidermal growth factor (EGF) or hepatocyte growth factor (HGF), BMP-4 potently enhanced growth factor-induced cell proliferation. These results reveal a hitherto unsuspected interplay between BMP-4 and growth factors in the regulation of mammary epithelial cell proliferation. We suggest that the ability of BMP-4 to potentiate the mitogenic activity of multiple growth factors may contribute to mammary gland ductal morphogenesis as well as to breast cancer progression.

  11. miRNA-1297 induces cell proliferation by targeting phosphatase and tensin homolog in testicular germ cell tumor cells.

    PubMed

    Yang, Nian-Qin; Zhang, Jian; Tang, Qun-Ye; Guo, Jian-Ming; Wang, Guo-Min

    2014-01-01

    To investigate the role of miR-1297 and the tumor suppressor gene PTEN in cell proliferation of testicular germ cell tumors (TGCT). MTT assays were used to test the effect of miR-1297 on proliferation of the NCCIT testicular germ cell tumor cell line. In NCCIT cells, the expression of PTEN was assessed by Western blotting further. In order to confirm target association between miR-1297 and 3'-UTR of PTEN, a luciferase reporter activity assay was employed. Moreover, roles of PTEN in proliferation of NCCIT cells were evaluated by transfection of PTEN siRNA. Proliferation of NCCIT cells was promoted by miR-1297 in a concentration-dependent manner. In addition, miR-1297 could bind to the 3'-UTR of PTEN based on luciferase reporter activity assay, and reduced expression of PTEN at protein level was found. Proliferation of NCCIT cells was significantly enhanced after knockdown of PTEN by siRNA. miR-1297 as a potential oncogene could induce cell proliferation by targeting PTEN in NCCIT cells. PMID:25124605

  12. Cell proliferation by silk gut incorporating FGF-2 protein microcrystals

    PubMed Central

    Kotani, Eiji; Yamamoto, Naoto; Kobayashi, Isao; Uchino, Keiro; Muto, Sayaka; Ijiri, Hiroshi; Shimabukuro, Junji; Tamura, Toshiki; Sezutsu, Hideki; Mori, Hajime

    2015-01-01

    Silk gut processed from the silk glands of the silkworm could be an ideal biodegradable carrier for cell growth factors. We previously demonstrated that polyhedra, microcrystals of Cypovirus 1 polyhedrin, can serve as versatile carrier proteins. Here, we report the generation of a transgenic silkworm that expresses polyhedrin together with human basic fibroblast growth factor (FGF-2) in its posterior silk glands to utilize silk gut as a proteinaceous carrier to protect and slowly release active cell growth factors. In the posterior silk glands, polyhedrin formed polyhedral microcrystals, and FGF-2 became encapsulated within the polyhedra due to a polyhedron-immobilization signal. Silk gut powder prepared from posterior silk glands containing polyhedron-encapsulated FGF-2 stimulated the phosphorylation of p44/p42 MAP kinase and induced the proliferation of serum-starved NIH3T3 cells by releasing bioactive FGF-2. Even after a one-week incubation at 25 °C, significantly higher biological activity of FGF-2 was observed for silk gut powder incorporating polyhedron-encapsulated FGF-2 relative to silk gut powder with non-encapsulated FGF-2. Our results demonstrate that posterior silk glands incorporating polyhedron-encapsulated FGF-2 are applicable to the preparation of biodegradable silk gut, which can protect and release FGF-2 that is produced in a virus- and serum-free expression system with significant application potential. PMID:26053044

  13. Inhibition of Cell Proliferation by an Anti-EGFR Aptamer

    PubMed Central

    Li, Na; Nguyen, Hong Hanh; Byrom, Michelle; Ellington, Andrew D.

    2011-01-01

    Aptamers continue to receive interest as potential therapeutic agents for the treatment of diseases, including cancer. In order to determine whether aptamers might eventually prove to be as useful as other clinical biopolymers, such as antibodies, we selected aptamers against an important clinical target, human epidermal growth factor receptor (hEGFR). The initial selection yielded only a single clone that could bind to hEGFR, but further mutation and optimization yielded a family of tight-binding aptamers. One of the selected aptamers, E07, bound tightly to the wild-type receptor (Kd = 2.4 nM). This aptamer can compete with EGF for binding, binds to a novel epitope on EGFR, and also binds a deletion mutant, EGFRvIII, that is commonly found in breast and lung cancers, and especially in grade IV glioblastoma multiforme, a cancer which has for the most part proved unresponsive to current therapies. The aptamer binds to cells expressing EGFR, blocks receptor autophosphorylation, and prevents proliferation of tumor cells in three-dimensional matrices. In short, the aptamer is a promising candidate for further development as an anti-tumor therapeutic. In addition, Aptamer E07 is readily internalized into EGFR-expressing cells, raising the possibility that it might be used to escort other anti-tumor or contrast agents. PMID:21687663

  14. Cell proliferation by silk gut incorporating FGF-2 protein microcrystals.

    PubMed

    Kotani, Eiji; Yamamoto, Naoto; Kobayashi, Isao; Uchino, Keiro; Muto, Sayaka; Ijiri, Hiroshi; Shimabukuro, Junji; Tamura, Toshiki; Sezutsu, Hideki; Mori, Hajime

    2015-01-01

    Silk gut processed from the silk glands of the silkworm could be an ideal biodegradable carrier for cell growth factors. We previously demonstrated that polyhedra, microcrystals of Cypovirus 1 polyhedrin, can serve as versatile carrier proteins. Here, we report the generation of a transgenic silkworm that expresses polyhedrin together with human basic fibroblast growth factor (FGF-2) in its posterior silk glands to utilize silk gut as a proteinaceous carrier to protect and slowly release active cell growth factors. In the posterior silk glands, polyhedrin formed polyhedral microcrystals, and FGF-2 became encapsulated within the polyhedra due to a polyhedron-immobilization signal. Silk gut powder prepared from posterior silk glands containing polyhedron-encapsulated FGF-2 stimulated the phosphorylation of p44/p42 MAP kinase and induced the proliferation of serum-starved NIH3T3 cells by releasing bioactive FGF-2. Even after a one-week incubation at 25 °C, significantly higher biological activity of FGF-2 was observed for silk gut powder incorporating polyhedron-encapsulated FGF-2 relative to silk gut powder with non-encapsulated FGF-2. Our results demonstrate that posterior silk glands incorporating polyhedron-encapsulated FGF-2 are applicable to the preparation of biodegradable silk gut, which can protect and release FGF-2 that is produced in a virus- and serum-free expression system with significant application potential. PMID:26053044

  15. [Envelope protein of Jaagsiekte sheep retrovious expressed in NIH3T3 cells promotes cell proliferation].

    PubMed

    DU, Fangyuan; Chen, Dayong; Zhang, Yufei; Sun, Xiaolin; Guo, Wenqing; Liu, Shuying

    2016-09-01

    Objective To explore the influence of the exogenous Jaagsiekte sheep retrovious (exJSRV) envelope protein (Env) on NIH3T3 cell proliferation. Methods A recombinant plasmid pcDNA4/myc-His/exJSRV- env carrying exJSRV- env gene was constructed, and then the correctness of the recombinant plasmid was identified by PCR, restriction enzyme digestion and sequencing. The recombinant plasmid pcDNA4/myc-His/exJSRV- env was transiently transfected into NIH3T3 cells by Lipofectamine(TM) LTX. After the transfection of the recombinant plasmid, the expression of exJSRV- env was detected by reverse transcription PCR and Western blotting. The effect of Env on cell proliferation was investigated by CCK-8 assay and plate colony formation assay. Results The recombinant eukaryotic expression plasmid containing exJSRV- env was successfully constructed as identified by PCR, restriction enzyme identification and sequencing. After the recombinant plasmid was transiently transfected into NIH3T3 cells, reverse transcription PCR and Western blotting showed the expression of exJSRV- env , and Env promoted NIH3T3 cell proliferation significantly. Conclusion JSRV Env was expressed successfully in the NIH3T3 cells and promoted the proliferation of NIH3T3 cells. PMID:27609573

  16. Cell signaling abnormalities may drive neurodegeneration in familial Alzheimer disease.

    PubMed

    Robakis, Nikolaos K

    2014-01-01

    Presenilins (PSs) are catalytic components of the γ-secretase complex that produces Aβ peptides. Substrates of γ-secretase are membrane-bound protein fragments deriving from the cleavage of extracellular sequence of cell surface proteins. APP-derived γ-secretase substrates are cleaved at gamma (γ) sites to produce Aβ while cleavage at the epsilon (ε) site produces AICD proposed to function in transcription. In addition to APP, γ-secretase promotes the ε-cleavage of a large number of cell surface proteins producing cytosolic peptides shown to function in cell signaling. A common hypothesis suggests that Alzheimer's disease (AD) is caused by Aβ peptides or their products. Treatment of patients with inhibitors of Aβ production however, showed no therapeutic benefits while inducing cytotoxicity. Similarly, treatments with anti-Aβ antibodies yielded disappointing results. Importantly, recent evidence shows that PS familial AD (FAD) mutations cause a loss of γ-secretase cleavage activity at ε site of substrates thus inhibiting production of biologically important cell signaling peptides while promoting accumulation of membrane-bound cytotoxic substrates. These data support a hypothesis that FAD mutations may increase neurotoxicity by inhibiting the γ-secretase-catalyzed ε cleavage of substrates thus interfering with cell signaling while also promoting accumulation of cytotoxic peptides. Similar mechanisms may explain γ-secretase inhibitor-associated toxicities observed in clinical trials. Here we discuss evidence that FAD neurodegeneration may be caused by loss of γ-secretase cleavage function at ε sites of substrates. PMID:23436150

  17. Cell proliferation and hair cell addition in the ear of the goldfish, Carassius auratus

    NASA Technical Reports Server (NTRS)

    Lanford, P. J.; Presson, J. C.; Popper, A. N.

    1996-01-01

    Cell proliferation and hair cell addition have not been studied in the ears of otophysan fish, a group of species who have specialized hearing capabilities. In this study we used the mitotic S-phase marker bromodeoxyuridine (BrdU) to identify proliferating cells in the ear of one otophysan species, Carassius auratus (the goldfish). Animals were sacrificed at 3 h or 5 days postinjection with BrdU and processed for immunocytochemistry. The results of the study show that cell proliferation occurs in all of the otic endorgans and results in the addition of new hair cells. BrdU-labeled cells were distributed throughout all epithelia, including the primary auditory endorgan (saccule), where hair cell phenotypes vary considerably along the rostrocaudal axis. This study lays the groundwork for our transmission electron microscopy study of proliferative cells in the goldfish ear (Presson et al., Hearing Research 100 (1996) 10-20) as well as future studies of hair cell development in this species. The ability to predict, based on epithelial location, the future phenotype of developing hair cells in the saccule of the goldfish make that endorgan a particularly powerful model system for the investigation of early hair cell differentiation.

  18. GSK3β isoform-selective regulation of depression, memory and hippocampal cell proliferation.

    PubMed

    Pardo, M; Abrial, E; Jope, R S; Beurel, E

    2016-03-01

    Abnormally active glycogen synthase kinase-3 (GSK3) contributes to pathological processes in multiple psychiatric and neurological disorders. Modeled in mice, this includes increasing susceptibility to dysregulation of mood-relevant behaviors, impairing performance in several cognitive tasks and impairing adult hippocampal neural precursor cell (NPC) proliferation. These deficits are all evident in GSK3α/β knockin mice, in which serine-to-alanine mutations block the inhibitory serine phosphorylation regulation of both GSK3 isoforms, leaving GSK3 hyperactive. It was unknown if both GSK3 isoforms perform redundant actions in these processes, or if hyperactivity of one GSK3 isoform has a predominant effect. To test this, we examined GSK3α or GSK3β knockin mice in which only one isoform was mutated to a hyperactive form. Only GSK3β, not GSK3α, knockin mice displayed heightened vulnerability to the learned helplessness model of depression-like behavior. Three cognitive measures impaired in GSK3α/β knockin mice showed differential regulation by GSK3 isoforms. Novel object recognition was impaired in GSK3β, not in GSK3α, knockin mice, whereas temporal order memory was not impaired in GSK3α or GSK3β knockin mice, and co-ordinate spatial processing was impaired in both GSK3α and GSK3β knockin mice. Adult hippocampal NPC proliferation was severely impaired in GSK3β knockin mice, but not impaired in GSK3α knockin mice. Increased activity of GSK3β, in the absence of overexpression or disease pathology, is sufficient to impair mood regulation, novel object recognition and hippocampal NPC proliferation, whereas hyperactive GSK3α individually does not impair these processes. These results show that hyperactivity of the two GSK3 isoforms execute non-redundant effects on these processes. PMID:26749572

  19. Dendritic Cell-Nerve Clusters Are Sites of T Cell Proliferation in Allergic Airway Inflammation

    PubMed Central

    Veres, Tibor Z.; Shevchenko, Marina; Krasteva, Gabriela; Spies, Emma; Prenzler, Frauke; Rochlitzer, Sabine; Tschernig, Thomas; Krug, Norbert; Kummer, Wolfgang; Braun, Armin

    2009-01-01

    Interactions between T cells and dendritic cells in the airway mucosa precede secondary immune responses to inhaled antigen. The purpose of this study was to identify the anatomical locations where dendritic cell–T cell interactions occur, resulting in T cells activation by dendritic cells. In a mouse model of allergic airway inflammation, we applied whole-mount immunohistology and confocal microscopy to visualize dendritic cells and T cells together with nerves, epithelium, and smooth muscle in three dimensions. Proliferating T cells were identified by the detection of the incorporation of the nucleotide analogue 5-ethynyl-2′-deoxyuridine into the DNA. We developed a novel quantification method that enabled the accurate determination of cell–cell contacts in a semi-automated fashion. Dendritic cell–T cell interactions occurred beneath the smooth muscle layer, but not in the epithelium. Approximately 10% of the dendritic cells were contacted by nerves, and up to 4% of T cells formed clusters with these dendritic cells. T cells that were clustered with nerve-contacting dendritic cells proliferated only in the airways of mice with allergic inflammation but not in the airways of negative controls. Taken together, these results suggest that during the secondary immune response, sensory nerves influence dendritic cell-driven T cell activation in the airway mucosa. PMID:19179611

  20. Focal adhesion protein abnormalities in myelodysplastic mesenchymal stromal cells

    SciTech Connect

    Aanei, Carmen Mariana; Eloae, Florin Zugun; Flandrin-Gresta, Pascale; Tavernier, Emmanuelle; Carasevici, Eugen; Guyotat, Denis; Campos, Lydia

    2011-11-01

    Direct cell-cell contact between haematopoietic progenitor cells (HPCs) and their cellular microenvironment is essential to maintain 'stemness'. In cancer biology, focal adhesion (FA) proteins are involved in survival signal transduction in a wide variety of human tumours. To define the role of FA proteins in the haematopoietic microenvironment of myelodysplastic syndromes (MDS), CD73-positive mesenchymal stromal cells (MSCs) were immunostained for paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} and p130CAS, and analysed for reactivity, intensity and cellular localisation. Immunofluorescence microscopy allowed us to identify qualitative and quantitative differences, and subcellular localisation analysis revealed that in pathological MSCs, paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} formed nuclear molecular complexes. Increased expression of paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} and enhanced nuclear co-localisation of these proteins correlated with a consistent proliferative advantage in MSCs from patients with refractory anaemia with excess blasts (RAEB) and negatively impacted clonogenicity of HPCs. These results suggest that signalling via FA proteins could be implicated in HPC-MSC interactions. Further, because FAK is an HSP90{alpha}/{beta} client protein, these results suggest the utility of HSP90{alpha}/{beta} inhibition as a target for adjuvant therapy for myelodysplasia.

  1. Deacetylase inhibitors modulate proliferation and self-renewal properties of leukemic stem and progenitor cells

    PubMed Central

    Romanski, Annette; Schwarz, Kerstin; Keller, Maren; Wietbrauk, Sarah; Vogel, Anja; Roos, Jessica; Oancea, Claudia; Brill, Boris; Krämer, Oliver H.; Serve, Hubert; Ruthardt, Martin; Bug, Gesine

    2012-01-01

    Acute myeloid leukemia (AML) is a highly malignant disease that is not curable in the majority of patients. Numerous non-random genetic abnormalities are known, among which several translocations such as PLZF/RARα or AML1/ETO are known to aberrantly recruit histone deacetylases. Deacetylase inhibitors (DACi) are promising drugs leading to growth inhibition, cell cycle arrest, premature senescence and apoptosis in malignant cells. It is believed that DACi may have clinical efficacy by eradicating the most primitive population of leukemic stem and progenitor cells, possibly by interfering with self-renewal. The aim of the study was to investigate the effects of DACi on leukemic stem and progenitor cells using murine transduction-transplantation models of hematopoietic cells harboring the leukemia-associated fusion proteins (LAFP) PLZF/RARα or a truncated AML1/ETO protein (AML1/ETO exon 9). We show that the self-renewal and short-term repopulation capacity of AML1/ETO- or PLZF/RARα-expressing Sca1+/lin- stem and progenitor cells are profoundly inhibited by clinically applicable concentrations of the DACi dacinostat and vorinostat. To further investigate the mechanisms underlying these effects, we examined the impact of DACi on the transcription factor c-MYC and the Polycomb group protein BMI1, which are induced by LAFP and involved in leukemic transformation. In AML1/ETO or PLZF/RARα-positive 32D cells, DACi-mediated antiproliferative effects were associated with downregulation of BMI1 and c-MYC protein levels. Similar effects were demonstrated in primary samples of cytogenetically defined high-risk AML patients. In conclusion, DACi may be effective as maintenance therapy by negatively interfering with signaling pathways that control survival and proliferation of leukemic stem and progenitor cells. PMID:22895185

  2. 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. PMID:26081645

  3. Cell cycle control in isoproterenol-induced murine salivary acinar cell proliferation.

    PubMed

    Zeng, T; Yamamoto, H; Bowen, E; Broverman, R L; Nguyen, K H; Humphreys-Beher, M G

    1996-11-01

    The eukaryotic cell cycle is a summary of a complex network of signal transduction pathways resulting in both DNA replication and cell division. Cyclin-dependent kinases (CDKs) control the cell cycle in all eukaryotes, whereas other proteins, known as cyclins, act as their regulatory subunits. Chronic injection with isoproterenol (ISO) can induce acinar cell proliferation in rodent salivary glands. Cyclins and CDK proteins from control and ISO-treated murine parotid acinar cells were detected by using Western blotting techniques. By comparing the expression of these cell cycle regulatory kinases in the parotid acinar cell transition from a quiescent state to a hypertrophic state, we found rapid increases in the protein levels of all CDKs, cyclin D and proliferating cell nuclear antigen (PCNA). The highest protein levels for CDKs and cyclins appeared at about 72 hr of ISO stimulation and were coincident with the highest rate of increase in gland wet weight. After 72 hr, the increase of both cell cycle protein and gland wet weight began to subside. By using a co-immunoprecipitation method, the following cell cycle regulators (CDK-cyclin complexes) were detected, CDK4-cyclin D, CDK2-cyclin E, CDK2-cyclin A, and cdc2-cyclin B, along with an increase in kinase activity over control untreated animals. Additionally, we detected significant decreases in the newly isolated CDK inhibitor (CKI) p27kip but not Wee 1 kinase. The increased levels of CKI correlated with a decrease in kinase activity of CDK/cyclin complexes by 144 hr of chronic isoproterenol treatment. Our data suggest that the holoenzymes for cell cycle control (cyclin-CDK complexes) function as a final regulatory mechanism leading to salivary gland acinar cell proliferation. The gradual decline in protein levels of the CDKs and cyclins after 3 days of chronic treatment further indicates that ISO-induced proliferation of parotid acinar cells is self-limiting and non-tumorigenic. PMID:9375366

  4. MicroRNA-541 promotes the proliferation of vascular smooth muscle cells by targeting IRF7

    PubMed Central

    Yang, Fang; Xu, Zonglei; Duan, Shaobin; Luo, Min

    2016-01-01

    MiRNAs play crucial roles in abnormal proliferation and invasion of VSMCs. However, the roles and mechanisms of miRNAs in VSMCs are not fully understood. In our study, we demonstrated that PDGF-BB and serum induced proliferation of VSMCs led to the upregulation of miR-541. We also showed that overexpression of miR-541 promoted VSMC proliferation and invasion. In addition, Interferon regulatory factor 7 (IRF7) was found to be a potential target of miR-541 and upregulation of IRF7 could inhibit VSMC proliferation. Restored expression of miR-541 promoted IRF7-inhibited VSMCs proliferation. In conclusion, these findings suggest that inhibitors targeting miR-541 or its specific downstream molecules may be therapeutic strategy for VSMC growth-related diseases. PMID:27158343

  5. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    SciTech Connect

    Wang, Ruoxing; Guo, Yan-Lin

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: Black-Right-Pointing-Pointer Inhibition of Cdks slows down mESCs proliferation. Black-Right-Pointing-Pointer mESCs display remarkable recovery capacity from short-term cell cycle interruption. Black-Right-Pointing-Pointer Short-term cell cycle interruption does not compromise mESC self-renewal. Black

  6. Hippo signaling regulates Drosophila intestine stem cell proliferation through multiple pathways

    PubMed Central

    Ren, Fangfang; Wang, Bing; Yue, Tao; Yun, Eun-Young; Ip, Y. Tony; Jiang, Jin

    2010-01-01

    Intestinal stem cells (ISCs) in the Drosophila adult midgut are essential for maintaining tissue homeostasis and replenishing lost cells in response to tissue damage. Here we demonstrate that the Hippo (Hpo) signaling pathway, an evolutionarily conserved pathway implicated in organ size control and tumorigenesis, plays an essential role in regulating ISC proliferation. Loss of Hpo signaling in either midgut precursor cells or epithelial cells stimulates ISC proliferation. We provide evidence that loss of Hpo signaling in epithelial cells increases the production of cytokines of the Upd family and multiple EGFR ligands that activate JAK-STAT and EGFR signaling pathways in ISCs to stimulate their proliferation, thus revealing a unique non–cell-autonomous role of Hpo signaling in blocking ISC proliferation. Finally, we show that the Hpo pathway mediator Yorkie (Yki) is also required in precursor cells for injury-induced ISC proliferation in response to tissue-damaging reagent DSS. PMID:21078993

  7. Pancreas-Specific Delivery of β-Cell Proliferating Small Molecules.

    PubMed

    Hao, Xueshi; Jin, Qihui; Va, Porino; Li, Chun; Shen, Weijun; Laffitte, Bryan; Wu, Tom Y-H

    2016-06-01

    Our research groups recently described a series of small-molecule inducers of β-cell proliferation that could be used to increase β-cell mass. To mitigate the risk of nonspecific proliferation of other cell types, we devised a delivery strategy built on the tissue specificity observed in the experimental β-cell imaging agent (+)-dihydrotetrabenazine (DTBZ). The β-cell proliferator agent aminopyrazine (AP) was covalently linked with (+)-DTBZ to afford conjugates that retain both the proliferation activity and binding affinity for vesicular monoamine transporter-2 (VMAT2). In vivo mouse tissue distribution studies of a prototypical AP-DTBZ conjugate showed 15-fold pancreas exposure over plasma. Tissue-to-plasma ratios in liver and kidneys were two- and five-fold, respectively. This work is the first demonstration of enhanced delivery of β-cell-proliferating molecules to the pancreas by leveraging the intrinsic tissue specificity of a β-cell imaging agent. PMID:27095073

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

    PubMed

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

    2016-06-01

    Dishevelled-2 (Dvl2) was associated with tumor cell proliferation and migration. We aimed to examine the mechanism of Dvl2 in esophageal squamous cell carcinoma (ESCC). Dvl2 was overexpressed in human ESCC tissues and cell lines ECA109 and TE1 cells. CCK-8 and colony formation assay was performed to evaluate the proliferation in ECA109 cells transfected with Dvl2-shRNA. Wound-healing assay and transwell assay were used to examine the activities of migration and invasion in Dvl2-silenced ESCC cells. Knockdown of Dvl2 significantly reduced ECA109 cell proliferation and migration. Moreover, we demonstrated that the proliferation and migration ability of Dvl2 might through the activation of Wnt pathway by targeting the Cyclin D1 and MMP-9. We came to the conclusion that the proliferation and migration effects of Dvl2 might contribute to malignant development of human ESCC. PMID:27083564

  9. In vivo cell-autonomous transcriptional abnormalities revealed in mice expressing mutant huntingtin in striatal but not cortical neurons.

    PubMed

    Thomas, Elizabeth A; Coppola, Giovanni; Tang, Bin; Kuhn, Alexandre; Kim, SoongHo; Geschwind, Daniel H; Brown, Timothy B; Luthi-Carter, Ruth; Ehrlich, Michelle E

    2011-03-15

    Huntington's disease (HD), caused by a CAG repeat expansion in the huntingtin (HTT) gene, is characterized by abnormal protein aggregates and motor and cognitive dysfunction. Htt protein is ubiquitously expressed, but the striatal medium spiny neuron (MSN) is most susceptible to dysfunction and death. Abnormal gene expression represents a core pathogenic feature of HD, but the relative roles of cell-autonomous and non-cell-autonomous effects on transcription remain unclear. To determine the extent of cell-autonomous dysregulation in the striatum in vivo, we examined genome-wide RNA expression in symptomatic D9-N171-98Q (a.k.a. DE5) transgenic mice in which the forebrain expression of the first 171 amino acids of human Htt with a 98Q repeat expansion is limited to MSNs. Microarray data generated from these mice were compared with those generated on the identical array platform from a pan-neuronal HD mouse model, R6/2, carrying two different CAG repeat lengths, and a relatively high degree of overlap of changes in gene expression was revealed. We further focused on known canonical pathways associated with excitotoxicity, oxidative stress, mitochondrial dysfunction, dopamine signaling and trophic support. While genes related to excitotoxicity, dopamine signaling and trophic support were altered in both DE5 and R6/2 mice, which may be either cell autonomous or non-cell autonomous, genes related to mitochondrial dysfunction, oxidative stress and the peroxisome proliferator-activated receptor are primarily affected in DE5 transgenic mice, indicating cell-autonomous mechanisms. Overall, HD-induced dysregulation of the striatal transcriptome can be largely attributed to intrinsic effects of mutant Htt, in the absence of expression in cortical neurons. PMID:21177255

  10. Alteration of T cell maturation and proliferation in the mouse thymus induced by serum factors from patients with ulcerative colitis.

    PubMed Central

    Watanabe, M; Aiso, S; Hibi, T; Watanabe, N; Iwao, Y; Yoshida, T; Asakura, H; Tsuru, S; Tsuchiya, M

    1987-01-01

    Recently it has been reported that patients with ulcerative colitis (UC) often have thymus abnormalities, although the precise mechanisms which induce those abnormalities remain unclear. We have examined the effect of serum fractions from patients with UC and other colonic diseases on mouse thymus to clarify the possible existence of factors which have thymus growth activity. These fractions were separated from sera of patients with UC by gel filtration and anion exchange high performance liquid chromatography. In mice given UC serum fractions; (i) remarkable increases in weight and total cell number of the thymus were observed from day 4 to day 9; (ii) a significant increase in the number of peanut agglutinin (PNA)+ thymus cells was demonstrated using flow cytometry on day 9; (iii) on quantitative analysis of surface antigens the percentage of Lyt-2+ thymus cells decreased and that of L3T4+ thymus cells increased remarkably on day 13; the number of bright Thy-1.2+ cells and of dull Lyt-1+ cells increased. In contrast, the serum fractions from patients with other colonic diseases and from normal persons caused little change in mouse thymus throughout the study. The results suggest that factors fractionated from the serum of patients with UC disturb intra-thymic T cell maturation and enhance the proliferation of thymus cells. PMID:3498579

  11. Citral inhibits cell proliferation and induces apoptosis and cell cycle arrest in MCF-7 cells.

    PubMed

    Chaouki, Wahid; Leger, David Y; Liagre, Bertrand; Beneytout, Jean-Louis; Hmamouchi, Mohamed

    2009-10-01

    Many natural components of plants extract are studied for their beneficial effects on health and particularly on carcinogenesis chemoprevention. In this study, we investigated the effect of citral (3,7-dimethyl-2,6-octadienal), a key component of essential oils extracted from several herbal plants, on the proliferation rate, cell cycle distribution, and apoptosis of the human breast cancer cell line MCF-7. The effects of this compound were also tested on cyclo-oxygenase activity. Citral treatment caused inhibition of MCF-7 cell growth (IC(50)-48 h: 18 x 10(-5)m), with a cycle arrest in G(2)/M phase and apoptosis induction. Moreover, we observed a decrease in prostaglandin E(2) synthesis 48 h after citral treatment. These findings suggest that citral has a potential chemopreventive effect. PMID:19656204

  12. In vivo genetic ablation of the periotic mesoderm affects cell proliferation survival and differentiation in the cochlea

    PubMed Central

    Xu, Huansheng; Chen, Li; Baldini, Antonio

    2007-01-01

    Tbx1 is required for ear development in humans and mice. Gene manipulation in the mouse has discovered multiple consequences of loss of function on early development of the inner ear, some of which are attributable to a cell autonomous role in maintaining cell proliferation of epithelial progenitors of the cochlear and vestibular apparata. However, ablation of the mesodermal domain of the gene also results in severe but more restricted abnormalities. Here we show that Tbx1 has a dynamic expression during late development of the ear, in particular, is expressed in the sensory epithelium of the vestibular organs but not of the cochlea. Vice versa, it is expressed in the condensed mesenchyme that surrounds the cochlea but not in the one that surrounds the vestibule. Loss of Tbx1 in the mesoderm disrupts this peri-cochlear capsule by strongly reducing the proliferation of mesenchymal cells. The organogenesis of the cochlea, which normally occurs inside the capsule, was dramatically affected in terms of growth of the organ, as well as proliferation, differentiation and survival of its epithelial cells. This model provides a striking demonstration of the essential role played by the periotic mesenchyme in the organogenesis of the cochlea. PMID:17825816

  13. Cell Junction Pathology of Neural Stem Cells Is Associated With Ventricular Zone Disruption, Hydrocephalus, and Abnormal Neurogenesis.

    PubMed

    Guerra, María Montserrat; Henzi, Roberto; Ortloff, Alexander; Lichtin, Nicole; Vío, Karin; Jiménez, Antonio J; Dominguez-Pinos, María Dolores; González, César; Jara, Maria Clara; Hinostroza, Fernando; Rodríguez, Sara; Jara, Maryoris; Ortega, Eduardo; Guerra, Francisco; Sival, Deborah A; den Dunnen, Wilfred F A; Pérez-Fígares, José M; McAllister, James P; Johanson, Conrad E; Rodríguez, Esteban M

    2015-07-01

    Fetal-onset hydrocephalus affects 1 to 3 per 1,000 live births. It is not only a disorder of cerebrospinal fluid dynamics but also a brain disorder that corrective surgery does not ameliorate. We hypothesized that cell junction abnormalities of neural stem cells (NSCs) lead to the inseparable phenomena of fetal-onset hydrocephalus and abnormal neurogenesis. We used bromodeoxyuridine labeling, immunocytochemistry, electron microscopy, and cell culture to study the telencephalon of hydrocephalic HTx rats and correlated our findings with those in human hydrocephalic and nonhydrocephalic human fetal brains (n = 12 each). Our results suggest that abnormal expression of the intercellular junction proteins N-cadherin and connexin-43 in NSC leads to 1) disruption of the ventricular and subventricular zones, loss of NSCs and neural progenitor cells; and 2) abnormalities in neurogenesis such as periventricular heterotopias and abnormal neuroblast migration. In HTx rats, the disrupted NSC and progenitor cells are shed into the cerebrospinal fluid and can be grown into neurospheres that display intercellular junction abnormalities similar to those of NSC of the disrupted ventricular zone; nevertheless, they maintain their potential for differentiating into neurons and glia. These NSCs can be used to investigate cellular and molecular mechanisms underlying this condition, thereby opening the avenue for stem cell therapy. PMID:26079447

  14. A Nanodot Array Modulates Cell Adhesion and Induces an Apoptosis-Like Abnormality in NIH-3T3 Cells

    NASA Astrophysics Data System (ADS)

    Pan, Hsu-An; Hung, Yao-Ching; Su, Chia-Wei; Tai, Shih-Ming; Chen, Chiun-Hsun; Ko, Fu-Hsiang; Steve Huang, G.

    2009-08-01

    Micro-structures that mimic the extracellular substratum promote cell growth and differentiation, while the cellular reaction to a nanostructure is poorly defined. To evaluate the cellular response to a nanoscaled surface, NIH 3T3 cells were grown on nanodot arrays with dot diameters ranging from 10 to 200 nm. The nanodot arrays were fabricated by AAO processing on TaN-coated wafers. A thin layer of platinum, 5 nm in thickness, was sputtered onto the structure to improve biocompatibility. The cells grew normally on the 10-nm array and on flat surfaces. However, 50-nm, 100-nm, and 200-nm nanodot arrays induced apoptosis-like events. Abnormality was triggered after as few as 24 h of incubation on a 200-nm dot array. For cells grown on the 50-nm array, the abnormality started after 72 h of incubation. The number of filopodia extended from the cell bodies was lower for the abnormal cells. Immunostaining using antibodies against vinculin and actin filament was performed. Both the number of focal adhesions and the amount of cytoskeleton were decreased in cells grown on the 100-nm and 200-nm arrays. Pre-coatings of fibronectin (FN) or type I collagen promoted cellular anchorage and prevented the nanotopography-induced programed cell death. In summary, nanotopography, in the form of nanodot arrays, induced an apoptosis-like abnormality for cultured NIH 3T3 cells. The occurrence of the abnormality was mediated by the formation of focal adhesions.

  15. The role of ribosomal proteins in the regulation of cell proliferation, tumorigenesis, and genomic integrity.

    PubMed

    Xu, Xilong; Xiong, Xiufang; Sun, Yi

    2016-07-01

    Ribosomal proteins (RPs), the essential components of the ribosome, are a family of RNA-binding proteins, which play prime roles in ribosome biogenesis and protein translation. Recent studies revealed that RPs have additional extra-ribosomal functions, independent of protein biosynthesis, in regulation of diverse cellular processes. Here, we review recent advances in our understanding of how RPs regulate apoptosis, cell cycle arrest, cell proliferation, neoplastic transformation, cell migration and invasion, and tumorigenesis through both MDM2/p53-dependent and p53-independent mechanisms. We also discuss the roles of RPs in the maintenance of genome integrity via modulating DNA damage response and repair. We further discuss mutations or deletions at the somatic or germline levels of some RPs in human cancers as well as in patients of Diamond-Blackfan anemia and 5q- syndrome with high susceptibility to cancer development. Moreover, we discuss the potential clinical application, based upon abnormal levels of RPs, in biomarker development for early diagnosis and/or prognosis of certain human cancers. Finally, we discuss the pressing issues in the field as future perspectives for better understanding the roles of RPs in human cancers to eventually benefit human health. PMID:27294833

  16. Diethylstilbestrol increases the density of prolactin cells in male mouse pituitary by inducing proliferation of prolactin cells and transdifferentiation of gonadotropic cells.

    PubMed

    Shukuwa, Keiko; Izumi, Shin-Ichi; Hishikawa, Yoshitaka; Ejima, Kuniaki; Inoue, Satoshi; Muramatsu, Masami; Ouchi, Yasuyoshi; Kitaoka, Takashi; Koji, Takehiko

    2006-07-01

    Diethylstilbestrol (DES) has been implicated in mammalian abnormalities. We examined the effects of DES on follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL) cells in the pituitaries of male mice treated with various doses of DES for 20 days. DES reduced the density of FSH and LH cells in a dose-dependent manner, but increased that of PRL cells. When the expression of estrogen receptor (ER) alpha and beta was assessed, an induction of ERbeta by DES was found predominantly in PRL cells. However, since these effects were abolished in ERalpha knockout mice, DES appears to act primarily through ERalpha. When the expression of Ki-67 and Pit-1 in PRL cells was examined at various time-points after DES treatment, some PRL cells became Ki-67 positive at 10-15 days, and Pit-1-positive cells were increased at 5-15 days. Furthermore, some FSH and LH cells became Pit-1 positive, and co-localized with PRL at 5-10 days. Our results indicate that DES increases PRL cells by inducing proliferation of PRL cells and transdifferentiation of FSH/LH cells to PRL cells. PMID:16468032

  17. 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.

  18. Development of ethynyl-2'-deoxyuridine chemical probes for cell proliferation.

    PubMed

    Lovitt, Carrie J; Hilko, David H; Avery, Vicky M; Poulsen, Sally-Ann

    2016-09-15

    A common method of evaluating cellular proliferation is to label DNA with chemical probes. 5-Ethynyl-2'-deoxyuridine (EdU) is a widely utilized chemical probe for labeling DNA, and upon incorporation, EdU treatment of cells is followed by a reaction with a small molecule fluorescent azide to allow detection. The limitations when using EdU include cytotoxicity and a reliance on nucleoside active transport mechanisms for entry into cells. Here we have developed six novel EdU pro-labels that consist of EdU modified with variable lipophilic acyl ester moieties. This pro-label:chemical probe relationship parallels the prodrug:drug relationship that is employed widely in medicinal chemistry. EdU and EdU pro-labels were evaluated for their labeling efficacy and cytotoxicity. Several EdU pro-label analogues incorporate into DNA at a similar level to EdU, suggesting that nucleoside transporters can be bypassed by the pro-labels. These EdU pro-labels also had reduced toxicity compared to EdU. PMID:27460697

  19. Shikonin Suppresses Skin Carcinogenesis via Inhibiting Cell Proliferation.

    PubMed

    Li, Wenjuan; Zhang, Chunjing; Ren, Amy; Li, Teena; Jin, Rong; Li, Guohong; Gu, Xin; Shi, Runhua; Zhao, Yunfeng

    2015-01-01

    The M2 isoform of pyruvate kinase M2 (PKM2) has been shown to be up-regulated in human skin cancers. To test whether PKM2 may be a target for chemoprevention, shikonin, a natural product from the root of Lithospermum erythrorhizon and a specific inhibitor of PKM2, was used in a chemically-induced mouse skin carcinogenesis study. The results revealed that shikonin treatment suppressed skin tumor formation. Morphological examinations and immunohistochemical staining of the skin epidermal tissues suggested that shikonin inhibited cell proliferation without inducing apoptosis. Although shikonin alone suppressed PKM2 activity, it did not suppress tumor promoter-induced PKM2 activation in the skin epidermal tissues at the end of the skin carcinogenesis study. To reveal the potential chemopreventive mechanism of shikonin, an antibody microarray analysis was performed, and the results showed that the transcription factor ATF2 and its downstream target Cdk4 were up-regulated by chemical carcinogen treatment; whereas these up-regulations were suppressed by shikonin. In a promotable skin cell model, the nuclear levels of ATF2 were increased during tumor promotion, whereas this increase was inhibited by shikonin. Furthermore, knockdown of ATF2 decreased the expression levels of Cdk4 and Fra-1 (a key subunit of the activator protein 1. In summary, these results suggest that shikonin, rather than inhibiting PKM2 in vivo, suppresses the ATF2 pathway in skin carcinogenesis. PMID:25961580

  20. Human NK cells proliferate and die in vivo more rapidly than T cells in healthy young and elderly adults.

    PubMed

    Lutz, Charles T; Karapetyan, Anush; Al-Attar, Ahmad; Shelton, Brent J; Holt, Kimberly J; Tucker, Jason H; Presnell, Steven R

    2011-04-15

    NK cells are essential for health, yet little is known about human NK turnover in vivo. In both young and elderly women, all NK subsets proliferated and died more rapidly than T cells. CD56(bright) NK cells proliferated rapidly but died relatively slowly, suggesting that proliferating CD56(bright) cells differentiate into CD56(dim) NK cells in vivo. The relationship between CD56(dim) and CD56(bright) proliferating cells indicates that proliferating CD56(dim) cells both self-renew and are derived from proliferating CD56(bright) NK cells. Our data suggest that some dying CD56(dim) cells become CD16(+)CD56(-) NK cells and that CD16(-)CD56(low) NK cells respond rapidly to cellular and cytokine stimulation. We propose a model in which all NK cell subsets are in dynamic flux. About half of CD56(dim) NK cells expressed CD57, which was weakly associated with low proliferation. Surprisingly, CD57 expression was associated with higher proliferation rates in both CD8(+) and CD8(-) T cells. Therefore, CD57 is not a reliable marker of senescent, nonproliferative T cells in vivo. NKG2A expression declined with age on both NK cells and T cells. Killer cell Ig-like receptor expression increased with age on T cells but not on NK cells. Although the percentage of CD56(bright) NK cells declined with age and the percentage of CD56(dim) NK cells increased with age, there were no significant age-related proliferation or apoptosis differences for these two populations or for total NK cells. In vivo human NK cell turnover is rapid in both young and elderly adults. PMID:21402893

  1. Effect of Lycium bararum polysaccharides on methylmercury-induced abnormal differentiation of hippocampal stem cells

    PubMed Central

    Tian, Jian-Ying; Chen, Wei-Wei; Cui, Jing; Wang, Hao; Chao, Ci; Lu, Zhi-Yan; Bi, Yong-Yi

    2016-01-01

    The aim of the present study was to observe the effects of a general extract of Lycium bararum polysaccharides (LBPs) on methylmercury (MeHg)-induced damage in hippocampus neural stem cells (hNSCs). The hippocampal tissues of embryonic day 16 Sprague-Dawley rats were extracted for the isolation, purification and cloning of hNSCs. Following passage and proliferation for 10 days, the cells were allocated at random into the following groups: Control, LBPs, MeHg and MeHg + LBPs. MTT and microtubule-associated protein 2 (MAP-2)/glial fibrillary acidic protein/Hoechst immunofluorescence tests were performed to detect the differentiation and growth of hNSCs in the various groups. The differentiation rate of MeHg-treated hNSCs and the perimeter of MAP-2-positive neurons were 3.632±0.63% and 62.36±5.58 µm, respectively, significantly lower compared with the control group values of 6.500±0.81% and 166±8.16 µm (P<0.05). Furthermore, the differentiation rate and the perimeter of MAP-2-positive neurons in LBPs groups cells was 7.75±0.59% and 253.3±11.21 µm, respectively, significantly higher compared with the control group (P<0.05). The same parameters in the MeHg + LBPs group were 5.92±0.98% and 111.9±6.07 µm, respectively, significantly higher than the MeHg group (P<0.05). The astrocyte differentiation rates in the MeHg and MeHg + LBPs group were 41.19±2.14 and 34.58±1.70, respectively (P<0.05). These results suggest that LBPs may promote the generation and development of new neurons and inhibit the MeHg-induced abnormal differentiation of astrocytes. Thus, LBPs may be considered to be a potential new treatment for MeHg-induced neurotoxicity in hNSCs. PMID:27446261

  2. Cocaine- and Amphetamine-regulated Transcript (CART) Protects Beta Cells against Glucotoxicity and Increases Cell Proliferation*

    PubMed Central

    Sathanoori, Ramasri; Olde, Björn; Erlinge, David; Göransson, Olga; Wierup, Nils

    2013-01-01

    Cocaine- and amphetamine-regulated transcript (CART) is an islet peptide that promotes glucose-stimulated insulin secretion in beta cells via cAMP/PKA-dependent pathways. In addition, CART is a regulator of neuronal survival. In this study, we examined the effect of exogenous CART 55–102 on beta cell viability and dissected its signaling mechanisms. Evaluation of DNA fragmentation and chromatin condensation revealed that CART 55–102 reduced glucotoxicity-induced apoptosis in both INS-1 (832/13) cells and isolated rat islets. Glucotoxicity in INS-1 (832/13) cells also caused a 50% reduction of endogenous CART protein. We show that CART increased proliferation in INS-1 (832/13) cells, an effect that was blocked by PKA, PKB, and MEK1 inhibitors. In addition, CART induced phosphorylation of CREB, IRS, PKB, FoxO1, p44/42 MAPK, and p90RSK in INS-1 (832/13) cells and isolated rat islets, all key mediators of cell survival and proliferation. Thus, we demonstrate that CART 55-102 protects beta cells against glucotoxicity and promotes proliferation. Taken together our data point to the potential use of CART in therapeutic interventions targeted at enhancing functional beta cell mass and long-term insulin secretion in T2D. PMID:23250745

  3. Cocaine- and amphetamine-regulated transcript (CART) protects beta cells against glucotoxicity and increases cell proliferation.

    PubMed

    Sathanoori, Ramasri; Olde, Björn; Erlinge, David; Göransson, Olga; Wierup, Nils

    2013-02-01

    Cocaine- and amphetamine-regulated transcript (CART) is an islet peptide that promotes glucose-stimulated insulin secretion in beta cells via cAMP/PKA-dependent pathways. In addition, CART is a regulator of neuronal survival. In this study, we examined the effect of exogenous CART 55-102 on beta cell viability and dissected its signaling mechanisms. Evaluation of DNA fragmentation and chromatin condensation revealed that CART 55-102 reduced glucotoxicity-induced apoptosis in both INS-1 (832/13) cells and isolated rat islets. Glucotoxicity in INS-1 (832/13) cells also caused a 50% reduction of endogenous CART protein. We show that CART increased proliferation in INS-1 (832/13) cells, an effect that was blocked by PKA, PKB, and MEK1 inhibitors. In addition, CART induced phosphorylation of CREB, IRS, PKB, FoxO1, p44/42 MAPK, and p90RSK in INS-1 (832/13) cells and isolated rat islets, all key mediators of cell survival and proliferation. Thus, we demonstrate that CART 55-102 protects beta cells against glucotoxicity and promotes proliferation. Taken together our data point to the potential use of CART in therapeutic interventions targeted at enhancing functional beta cell mass and long-term insulin secretion in T2D. PMID:23250745

  4. Suppression of PAX6 promotes cell proliferation and inhibits apoptosis in human retinoblastoma cells.

    PubMed

    Meng, Bo; Wang, Yisong; Li, Bin

    2014-08-01

    The aim of this study was to investigate the role of the transcription factor, PAX6, in the development of retinoblastoma. The expression of endogenous PAX6 was knocked down using PAX6-specific lentivirus in two human retinoblastoma cell lines, SO-Rb50 and Y79. Cell proliferation functional assays and apoptotic assays were performed on the cells in which PAX6 was knocked down. The results revealed that PAX6 knockdown efficiency was significant (P<0.01, n=3) in the SO-Rb50 and Y79 cells. The inhibition of PAX6 reduced tumor cell apoptosis (P<0.05, n=3), but induced cell cycle S phase arrest (SO-Rb50; P<0.05, n=3) and G2/M phase arrest (Y79; P<0.05, n=3). Western blot analysis indicated that the inhibition of PAX6 increased the levels of the anti-apoptotic proteins, Bcl-2, proliferating cell nuclear antigen (PCNA) and CDK1, but reduced the levels of the pro-apoptotic proteins, BAX and p21. In conclusion, our data demonstrate that the suppression of PAX6 increases proliferation and decreases apoptosis in human retinoblastoma cells by regulating several cell cycle and apoptosis biomarkers. PMID:24939714

  5. Suppression of PAX6 promotes cell proliferation and inhibits apoptosis in human retinoblastoma cells

    PubMed Central

    MENG, BO; WANG, YISONG; LI, BIN

    2014-01-01

    The aim of this study was to investigate the role of the transcription factor, PAX6, in the development of retinoblastoma. The expression of endogenous PAX6 was knocked down using PAX6-specific lentivirus in two human retinoblastoma cell lines, SO-Rb50 and Y79. Cell proliferation functional assays and apoptotic assays were performed on the cells in which PAX6 was knocked down. The results revealed that PAX6 knockdown efficiency was significant (P<0.01, n=3) in the SO-Rb50 and Y79 cells. The inhibition of PAX6 reduced tumor cell apoptosis (P<0.05, n=3), but induced cell cycle S phase arrest (SO-Rb50; P<0.05, n=3) and G2/M phase arrest (Y79; P<0.05, n=3). Western blot analysis indicated that the inhibition of PAX6 increased the levels of the anti-apoptotic proteins, Bcl-2, proliferating cell nuclear antigen (PCNA) and CDK1, but reduced the levels of the pro-apoptotic proteins, BAX and p21. In conclusion, our data demonstrate that the suppression of PAX6 increases proliferation and decreases apoptosis in human retinoblastoma cells by regulating several cell cycle and apoptosis biomarkers. PMID:24939714

  6. Growth and differentiation of circulating hemopoietic stem cells with atomic bomb irradiation-induced chromosome abnormalities

    SciTech Connect

    Amenomori, T.; Honda, T.; Otake, M.; Tomonaga, M.; Ichimaru, M.

    1988-11-01

    The effects of atomic bomb irradiation on hemopoietic stem cells were studied cytogenetically using single colonies derived from hemopoietic progenitor cells. The subjects studied were 21 healthy atomic bomb survivors (10 males and 11 females) in the high dose exposure group (100+ rad) with a known high incidence (10% or more) of radiation-induced chromosome abnormalities in their peripheral blood lymphocytes (stimulated with phytohemagglutinin), and 11 nonexposed healthy controls (5 males and 6 females). Colony formation by circulating granulocyte-macrophage (GM-CFC) and erythroid (BFU-E) progenitor cells was made by the methylcellulose method using peripheral blood mononuclear cells. Chromosome specimens were prepared from single colonies by our micromethod. The total number of colonies analyzed in the exposed group was 131 for GM-CFC and 75 for BFU-E. Chromosome abnormalities were observed in 15 (11.5%) and 9 (12.0%) colonies, respectively. In the control group, the total number of colonies analyzed was 61 for GM-CFC and 41 for BFU-E. None of these colonies showed chromosome abnormalities. The difference in incidence of chromosome abnormalities was highly significant by an exact test; p = 0.003 for GM-CFC and 0.017 for BFU-E. The karyotypes of chromosome abnormalities obtained from the colonies in the exposed group were mostly translocations, but deletion and marker chromosomes were also observed. In two individuals, such karyotypic abnormalities as observed in the peripheral lymphocytes were also seen in the myeloid progenitor cells. This finding suggests that atomic bomb irradiation produced a chromosome aberration on multipotent hemopoietic stem cells common to myeloid and lymphoid lineages.

  7. Accumulation of abnormal adult-generated hippocampal granule cells predicts seizure frequency and severity

    PubMed Central

    Hester, Michael S.; Danzer, Steve C.

    2013-01-01

    Accumulation of abnormally integrated, adult-born, hippocampal dentate granule cells (DGC) is hypothesized to contribute to the development of temporal lobe epilepsy (TLE). DGCs have long been implicated in TLE, as they regulate excitatory signaling through the hippocampus and exhibit neuroplastic changes during epileptogenesis. Furthermore, DGCs are unusual in that they are continually generated throughout life, with aberrant integration of new cells underlying the majority of restructuring in the dentate during epileptogenesis. While it is known that these abnormal networks promote abnormal neuronal firing and hyperexcitability, it has yet to be established whether they directly contribute to seizure generation. If abnormal DGCs do contribute, a reasonable prediction would be that the severity of epilepsy will be correlated with the number or load of abnormal DGCs. To test this prediction, we utilized a conditional, inducible transgenic mouse model to fate-map adult-generated DGCs. Mossy cell loss, also implicated in epileptogenesis, was assessed as well. Transgenic mice rendered epileptic using the pilocarpine-status epilepticus model of epilepsy were monitored 24/7 by video/EEG for four weeks to determine seizure frequency and severity. Positive correlations were found between seizure frequency and: 1) the percentage of hilar ectopic DGCs, 2) the amount of mossy fiber sprouting and 3) the extent of mossy cell death. In addition, mossy fiber sprouting and mossy cell death were correlated with seizure severity. These studies provide correlative evidence in support of the hypothesis that abnormal DGCs contribute to the development of TLE, and also support a role for mossy cell loss. PMID:23699504

  8. YAP Regulates Cell Proliferation, Migration, and Steroidogenesis in Adult Granulosa Cell Tumors

    PubMed Central

    Fu, David; Lv, Xiangmin; Hua, Guohua; He, Chunbo; Dong, Jixin; Lele, Subodh M.; Li, David Wan-Cheng; Zhai, Qiongli; Davis, John S.; Wang, Cheng

    2014-01-01

    The Hippo signaling pathway has been implicated as a conserved regulator of organ size in both Drosophila and mammals. Yes associated protein (YAP), the central component of the Hippo signaling cascade, functions as an oncogene in several malignancies. Ovarian granulosa cell tumors (GCT) are characterized by enlargement of ovary, excess production of estrogen, high frequency of recurrence and potential of malignancy and metastasis. Whether the Hippo pathway plays a role in the pathogenesis of GCT is unknown. This study was conducted to examine the expression of YAP in human adult GCTs and to determine the role of YAP in the proliferation and steroidogenesis of GCT cells. Compared with age-matched normal human ovaries, GCT tissues exhibited higher levels of YAP expression. YAP protein was predominantly expressed in the nucleus of tumor cells, whereas the non-tumor ovarian stromal cells expressed very low levels of YAP. YAP was also expressed in cultured primary human granulosa cells and in KGN and COV434 GCT cell lines. siRNA-mediated knockdown of YAP in KGN cells resulted in a significant reduction in cell proliferation (P<0.001). Conversely, overexpression of wild-type YAP or a constitutively active YAP mutant resulted in a significant increase in KGN cell proliferation and migration. Moreover, YAP knockdown reduced FSH-induced aromatase (CYP19A1) protein expression and estrogen production in KGN cells. These results demonstrate that YAP plays an important role in regulating GCT cell proliferation, migration and steroidogenesis. Targeting the Hippo/YAP pathway may provide a novel therapeutic approach for GCT. PMID:24389730

  9. Nitric oxide stimulates the proliferation of neural stem cells bypassing the epidermal growth factor receptor.

    PubMed

    Carreira, Bruno Pereira; Morte, Maria Inês; Inácio, Angela; Costa, Gabriel; Rosmaninho-Salgado, Joana; Agasse, Fabienne; Carmo, Anália; Couceiro, Patrícia; Brundin, Patrik; Ambrósio, António Francisco; Carvalho, Caetana Monteiro; Araújo, Inês Maria

    2010-07-01

    Nitric oxide (NO) was described to inhibit the proliferation of neural stem cells. Some evidence suggests that NO, under certain conditions, can also promote cell proliferation, although the mechanisms responsible for a potential proliferative effect of NO in neural stem cells have remained unaddressed. In this work, we investigated and characterized the proliferative effect of NO in cell cultures obtained from the mouse subventricular zone. We found that the NO donor NOC-18 (10 microM) increased cell proliferation, whereas higher concentrations (100 microM) inhibited cell proliferation. Increased cell proliferation was detected rapidly following exposure to NO and was prevented by blocking the mitogen-activated kinase (MAPK) pathway, independently of the epidermal growth factor (EGF) receptor. Downstream of the EGF receptor, NO activated p21Ras and the MAPK pathway, resulting in a decrease in the nuclear presence of the cyclin-dependent kinase inhibitor 1, p27(KIP1), allowing for cell cycle progression. Furthermore, in a mouse model that shows increased proliferation of neural stem cells in the hippocampus following seizure injury, we observed that the absence of inducible nitric oxide synthase (iNOS(-/-) mice) prevented the increase in cell proliferation observed following seizures in wild-type mice, showing that NO from iNOS origin is important for increased cell proliferation following a brain insult. Overall, we show that NO is able to stimulate the proliferation of neural stem cells bypassing the EGF receptor and promoting cell division. Moreover, under pathophysiological conditions in vivo, NO from iNOS origin also promotes proliferation in the hippocampus. PMID:20506358

  10. 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.

  11. The effects of physiological adaptations to calorie restriction on global cell proliferation rates.

    PubMed

    Bruss, Matthew D; Thompson, Airlia C S; Aggarwal, Ishita; Khambatta, Cyrus F; Hellerstein, Marc K

    2011-04-01

    Calorie restriction (CR) reduces the rate of cell proliferation in mitotic tissues. It has been suggested that this reduction in cell proliferation may mediate CR-induced increases in longevity. However, the mechanisms that lead to CR-induced reductions in cell proliferation rates remain unclear. To evaluate the CR-induced physiological adaptations that may mediate reductions in cell proliferation rates, we altered housing temperature and access to voluntary running wheels to determine the effects of food intake, energy expenditure, percent body fat, and body weight on proliferation rates of keratinocytes, liver cells, mammary epithelial cells, and splenic T-cells in C57BL/6 mice. We found that ∼20% CR led to a reduction in cell proliferation rates in all cell types. However, lower cell proliferation rates were not observed with reductions in 1) food intake and energy expenditure in female mice housed at 27°C, 2) percent body fat in female mice provided running wheels, or 3) body weight in male mice provided running wheels compared with ad libitum-fed controls. In contrast, reductions in insulin-like growth factor I were associated with decreased cell proliferation rates. Taken together, these data suggest that CR-induced reductions in food intake, energy expenditure, percent body fat, and body weight do not account for the reductions in global cell proliferation rates observed in CR. In addition, these data are consistent with the hypothesis that reduced cell proliferation rates could be useful as a biomarker of interventions that increase longevity. PMID:21285400

  12. The marine-derived fungal metabolite, terrein, inhibits cell proliferation and induces cell cycle arrest in human ovarian cancer cells.

    PubMed

    Chen, Yi-Fei; Wang, Shu-Ying; Shen, Hong; Yao, Xiao-Fen; Zhang, Feng-Li; Lai, Dongmei

    2014-12-01

    The difficulties faced in the effective treatment of ovarian cancer are multifactorial, but are mainly associated with relapse and drug resistance. Cancer stem-like cells have been reported to be an important contributor to these hindering factors. In this study, we aimed to investigate the anticancer activities of a bioactive fungal metabolite, namely terrein, against the human epithelial ovarian cancer cell line, SKOV3, primary human ovarian cancer cells and ovarian cancer stem-like cells. Terrein was separated and purified from the fermentation metabolites of the marine sponge-derived fungus, Aspergillus terreus strain PF26. Its anticancer activities against ovarian cancer cells were investigated by cell proliferation assay, cell migration assay, cell apoptosis and cell cycle assays. The ovarian cancer stem-like cells were enriched and cultured in a serum-free in vitro suspension system. Terrein inhibited the proliferation of the ovarian cancer cells by inducing G2/M phase cell cycle arrest. The underlying mechanisms involved the suppression of the expression of LIN28, an important marker gene of stemness in ovarian cancer stem cells. Of note, our study also demonstrated the ability of terrein to inhibit the proliferation of ovarian cancer stem-like cells, in which the expression of LIN28 was also downregulated. Our findings reveal that terrein (produced by fermention) may prove to be a promising drug candidate for the treatment of ovarian cancer by inhibiting the proliferation of cancer stem-like cells. PMID:25318762

  13. RMP Plays Distinct Roles in the Proliferation of Hepatocellular Carcinoma Cells and Normal Hepatic Cells

    PubMed Central

    Yang, Sijun; Wang, Hongmin; Guo, Yunlan; Chen, Shaomu; Zhang, Mei-Yin; Shen, Jian; Yu, Huijun; Miao, Jingcheng; Wang, Hui-Yun; Wei, Wenxiang

    2013-01-01

    RMP has been shown to function in the transcription regulation through association with RNA polymerase (RNAP) II subunit RPB5. It also has been shown to be required for the proliferation of hepatocellular carcinoma (HCC) cells with an antiapoptotic property. In this article, we further demonstrate that RMP displays distinct features in HCC cells compared with normal hepatic cells. RMP expression is remarkably increased in various cancer cell lines including HCC cells when compared with normal cells. Depletion of RMP could inhibit the proliferation of HCC cells, but not the normal hepatic cells. RMP significantly prevented apoptosis of HCC cells in SMMC-7721 and HepG2, but had little effect on apoptosis in the normal hepatic cells. The mechanisms of RMP's distinct features rely on different responsive expressions of apoptosis factors induced by RMP in HCC and hepatic cells. Either overexpression or depletion of RMP significantly affected the expression of apoptosis factors in HCC cells. However, normal hepatic cells showed a tendency to resist RMP for the regulation of apoptosis. In the clinical samples, the increased expression of RMP in HCCs was also observed when compared with the matched non-tumor tissues from 30 HCC patients. The different expression levels of and distinct responses to RMP between HCC and hepatic cells suggest that RMP might serve as not only a biomarker for the diagnosis of HCC, but also a potential target for the HCC therapy. PMID:23847445

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

    SciTech Connect

    Hatkevich, Talia; Ramos, Joseph; Santos-Sanchez, Idalys; Patel, Yashomati M.

    2014-10-01

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

  15. Construction of interference vector targeting Ep-CAM gene and its effects on colorectal cancer cell proliferation

    PubMed Central

    Qi, Yanmei; Zhou, Fengqiang; Zhang, Lu; Liu, Lei; Xu, Hong; Guo, Huiguang

    2015-01-01

    Background Prior study indicates that abnormal protein expression and functional changes in the development and progression of colorectal cancer is related to gene expression. The aim of this study was to construct an interference plasmid targeting the Ep-CAM gene and to investigate its effects on the proliferation of colorectal cancer cells. Methods In this study, HT-29 and HCT-116 colorectal cancer cell lines were selected as cell models. The double-stranded micro (mi)RNA oligo was inserted into the pcDNATM6.2-GW/EmGFPmiR vector, which is an expression of miRNA. Lipofectamine™ 2000 was used to transfer plasmid into the empty plasmid group (transfected pcDNATM6.2-GW/EmGFPmiR-neg) and the interference group (transfected pcDNATM6.2-GW/EmGFPmiR-Ep-CAM-1), respectively. Meanwhile, the nontransferred HT-29 and HCT-116 acts as the blank control group. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the transfection efficiency. Western blot was used to detect Ep-CAM protein expression. The cell proliferation in each group was detected by using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results The results indicated that the Ep-CAM messenger (m)RNA expression in the interference group was lower significantly compared with that of the empty plasmid group and control group (P<0.01). Western blot analysis results showed that Ep-CAM protein expression was significantly lower in interference group compared with that of the empty plasmid group and the control group (P<0.01). MTT assay results demonstrated that the proliferation ability of cells in the interference group was significantly inhibited compared with the two other groups (P<0.05). Conclusion Silencing of Ep-CAM can significantly inhibit the proliferation of colorectal cancer cells. PMID:26028961

  16. MYC-repressed long noncoding RNAs antagonize MYC-induced cell proliferation and cell cycle progression

    PubMed Central

    Jeon, Young-Jun; Fadda, Paolo; Alder, Hansjuerg; Croce, Carlo M.

    2015-01-01

    The transcription factor MYC is a proto-oncogene regulating cell proliferation, cell cycle, apoptosis and metabolism. The recent identification of MYC-regulated long noncoding RNAs (lncRNAs) expands our knowledge of the role of lncRNAs in MYC functions. Here, we identify MYC-repressed lncRNAs named MYCLo-4, -5 and -6 by comparing 3 categories of lncRNAs (downregulated in highly MYC-expressing colorectal cancer, up-regulated by MYC knockdown in HCT116, upregulated by MYC knockdown in RKO). The MYC-repressed MYCLos are implicated in MYC-modulated cell proliferation through cell cycle regulation. By screening cell cycle-related genes regulated by MYC and the MYC-repressed MYCLos, we identified the MYC-repressed gene GADD45A as a target gene of the MYC-repressed MYCLos such as MYCLo-4 and MYCLo-6. PMID:26003165

  17. 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

  18. Spirulina Promotes Stem Cell Genesis and Protects against LPS Induced Declines in Neural Stem Cell Proliferation

    PubMed Central

    Bachstetter, Adam D.; Jernberg, Jennifer; Schlunk, Andrea; Vila, Jennifer L.; Hudson, Charles; Cole, Michael J.; Shytle, R. Douglas; Tan, Jun; Sanberg, Paul R.; Sanberg, Cyndy D.; Borlongan, Cesario; Kaneko, Yuji; Tajiri, Naoki; Gemma, Carmelina; Bickford, Paula C.

    2010-01-01

    Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1β in the hippocampus of aged rats reversed the age-related cognitive decline and increased neurogenesis in the age rats. We also have found that nutraceuticals have the potential to reduce neuroinflammation, and decrease oxidative stress. The objectives of this study were to determine if spirulina could protect the proliferative potential of hippocampal neural progenitor cells from an acute systemic inflammatory insult of lipopolysaccharide (LPS). To this end, young rats were fed for 30 days a control diet or a diet supplemented with 0.1% spirulina. On day 28 the rats were given a single i.p. injection of LPS (1 mg/kg). The following day the rats were injected with BrdU (50 mg/kg b.i.d. i.p.) and were sacrificed 24 hours after the first injection of BrdU. Quantification of the BrdU positive cells in the subgranular zone of the dentate gyrus demonstrated a decrease in proliferation of the stem/progenitor cells in the hippocampus as a result of the LPS insult. Furthermore, the diet supplemented with spirulina was able to negate the LPS induced decrease in stem/progenitor cell proliferation. In a second set of studies we examined the effects of spirulina either alone or in combination with a proprietary formulation (NT-020) of blueberry, green tea, vitamin D3 and carnosine on the function of bone marrow and CD34+ cells in vitro. Spirulina had small effects on its own and more than additive effects in combination with NT-020 to promote mitochondrial respiration and/or proliferation of these cells in culture. When examined on neural stem cells in culture spirulina increased proliferation at baseline and protected against the negative

  19. NGF induces adult stem Leydig cells to proliferate and differentiate during Leydig cell regeneration

    SciTech Connect

    Zhang, Lei; Wang, Huaxi; Yang, Yan; Liu, Hui; Zhang, Qihao; Xiang, Qi; Ge, Renshan; Su, Zhijian; Huang, Yadong

    2013-06-28

    Highlights: •Nerve growth factor has shown significant changes on mRNA levels during Adult Leydig cells regeneration. •We established the organ culture model of rat seminiferous tubules with ethane dimethyl sulphonate (EDS) treatment. •Nerve growth factor has shown proliferation and differentiation-promoting effects on Adult stem Leydig cells. •Nerve growth factor induces progenitor Leydig cells to proliferate and differentiate and immature Leydig cells to proliferate. -- Abstract: Nerve growth factor (NGF) has been reported to be involved in male reproductive physiology. However, few reports have described the activity of NGF during Leydig cell development. The objective of the present study was to examine the role of NGF during stem-Leydig-cell (SLC) regeneration. We investigated the effects of NGF on Leydig-cell (LC) regeneration by measuring mRNA levels in the adult rat testis after ethane dimethanesulfonate (EDS) treatment. Furthermore, we used the established organ culture model of rat seminiferous tubules to examine the regulation of NGF during SLC proliferation and differentiation using EdU staining, real-time PCR and western blotting. Progenitor Leydig cells (PLCs) and immature Leydig cells (ILCs) were also used to investigate the effects of NGF on LCs at different developmental stages. NGF mRNA levels changed significantly during Leydig-cell regeneration in vivo. In vitro, NGF significantly promoted the proliferation of stem Leydig cells and also induced steroidogenic enzyme gene expression and 3β-HSD protein expression. The data from PLCs and ILCs showed that NGF could increase Cyclin D1 and Hsd 17b3 mRNA levels in PLCs and Cyclin D1 mRNA levels in ILCs. These results indicate that NGF may play an important role during LC regeneration by regulating the proliferation and differentiation of LCs at different developmental stages, from SLCs to PLCs and from PLCs to ILCs. The discovery of this effect of NGF on Leydig cells will provide useful

  20. WS6 induces both alpha and beta cell proliferation without affecting differentiation or viability

    PubMed Central

    Boerner, Brian P.; George, Nicholas M.; Mir, Shakeel U.R.; Sarvetnick, Nora E.

    2016-01-01

    Agents that stimulate human pancreatic beta cell proliferation are needed to improve diabetes mellitus treatment. Recently, a small molecule, WS6, was observed to stimulate human beta cell proliferation. However, little is known about its other effects on human islets. To better understand the role of WS6 as a possible beta cell regenerative therapy, we carried out in-depth phenotypic analysis of WS6-treated human islets, exploring its effects on non-beta cell proliferation, beta cell differentiation, and islet cell viability. WS6 not only stimulated beta cell proliferation in cultured human islets (in agreement with previous reports), but also human alpha cell proliferation, indicating that WS6 is not a beta cell-specific mitogen. WS6 did not change the proportion of insulin-positive beta cells or the expression of beta cell-specific transcription factors, suggesting that WS6 does not alter beta cell differentiation, and WS6 had no effect on human islet cell apoptosis or viability. In conclusion, WS6 stimulates proliferation of both human beta and alpha cells while maintaining cellular viability and the beta cell differentiated phenotype. These findings expand the literature on WS6 and support the suggestion that WS6 may help increase human islet mass needed for successful treatment of diabetes. PMID:25739404

  1. Armet, a UPR-upregulated protein, inhibits cell proliferation and ER stress-induced cell death

    SciTech Connect

    Apostolou, Andria; Shen Yuxian; Liang Yan; Luo Jun; Fang Shengyun

    2008-08-01

    The accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress that initiates the unfolded protein response (UPR). UPR activates both adaptive and apoptotic pathways, which contribute differently to disease pathogenesis. To further understand the functional mechanisms of UPR, we identified 12 commonly UPR-upregulated genes by expression microarray analysis. Here, we describe characterization of Armet/MANF, one of the 12 genes whose function was not clear. We demonstrated that the Armet/MANF protein was upregulated by various forms of ER stress in several cell lines as well as by cerebral ischemia of rat. Armet/MANF was localized in the ER and Golgi and was also a secreted protein. Silencing Armet/MANF by siRNA oligos in HeLa cells rendered cells more susceptible to ER stress-induced death, but surprisingly increased cell proliferation and reduced cell size. Overexpression of Armet/MANF inhibited cell proliferation and improved cell viability under glucose-free conditions and tunicamycin treatment. Based on its inhibitory properties for both proliferation and cell death we have demonstrated, Armet is, thus, a novel secreted mediator of the adaptive pathway of UPR.

  2. Cell-laden microengineered pullulan methacrylate hydrogels promote cell proliferation and 3D cluster formation.

    PubMed

    Bae, Hojae; Ahari, Amir F; Shin, Hyeongho; Nichol, Jason W; Hutson, Che B; Masaeli, Mahdokht; Kim, Su-Hwan; Aubin, Hug; Yamanlar, Seda; Khademhosseini, Ali

    2011-01-01

    The ability to encapsulate cells in three-dimensional (3D) environments is potentially of benefit for tissue engineering and regenerative medicine. In this paper, we introduce pullulan methacrylate (PulMA) as a promising hydrogel platform for creating cell-laden microscale tissues. The hydration and mechanical properties of PulMA were demonstrated to be tunable through modulation of the degree of methacrylation and gel concentration. Cells encapsulated in PulMA exhibited excellent viability. Interestingly, while cells did not elongate in PulMA hydrogels, cells proliferated and organized into clusters, the size of which could be controlled by the hydrogel composition. By mixing with gelatin methacrylate (GelMA), the biological properties of PulMA could be enhanced as demonstrated by cells readily attaching to, proliferating, and elongating within the PulMA/GelMA composite hydrogels. These data suggest that PulMA hydrogels could be useful for creating complex, cell-responsive microtissues, especially for applications that require controlled cell clustering and proliferation. PMID:21415929

  3. Acetylcholinesterase is associated with a decrease in cell proliferation of hepatocellular carcinoma cells.

    PubMed

    Pérez-Aguilar, Benjamín; Vidal, Cecilio J; Palomec, Guillermina; García-Dolores, Fernando; Gutiérrez-Ruiz, María Concepción; Bucio, Leticia; Gómez-Olivares, José Luis; Gómez-Quiroz, Luis Enrique

    2015-07-01

    Acetylcholinesterase (AChE), the enzyme that rapidly splits acetylcholine into acetate and choline, presents non-cholinergic functions through which may participate in the control of cell proliferation and apoptosis. These two features are relevant in cancer, particularly in hepatocellular carcinoma (HCC), a very aggressive liver tumor with high incidence and poor prognosis in advanced stages. Here we explored the relation between acetylcholinesterase and HCC growth by testing the influence of AChE on proliferation of Huh-7 and HepG2 cell lines, addressed in monolayer cultures, spheroid formation and human liver tumor samples. Results showed a clear relation in AChE expression and cell cycle progression, an effect which depended on cell confluence. Inhibition of AChE activity led to an increase in cell proliferation, which was associated with downregulation of p27 and cyclins. The fact that Huh-7 and HepG2 cell lines provided similar results lent weight to the relationship of AChE expression with cell cycle progression in hepatoma cell lines at least. Human liver tumor samples exhibited a decrease in AChE activity as compared with normal tissue. The evidence presented herein provides additional support for the proposed tumor suppressor role of AChE, which makes it a potential therapeutic target in therapies against hepatocellular carcinoma. PMID:25869328

  4. Fatostatin Inhibits Cancer Cell Proliferation by Affecting Mitotic Microtubule Spindle Assembly and Cell Division.

    PubMed

    Gholkar, Ankur A; Cheung, Keith; Williams, Kevin J; Lo, Yu-Chen; Hamideh, Shadia A; Nnebe, Chelsea; Khuu, Cindy; Bensinger, Steven J; Torres, Jorge Z

    2016-08-12

    The sterol regulatory element-binding protein (SREBP) transcription factors have become attractive targets for pharmacological inhibition in the treatment of metabolic diseases and cancer. SREBPs are critical for the production and metabolism of lipids and cholesterol, which are essential for cellular homeostasis and cell proliferation. Fatostatin was recently discovered as a specific inhibitor of SREBP cleavage-activating protein (SCAP), which is required for SREBP activation. Fatostatin possesses antitumor properties including the inhibition of cancer cell proliferation, invasion, and migration, and it arrests cancer cells in G2/M phase. Although Fatostatin has been viewed as an antitumor agent due to its inhibition of SREBP and its effect on lipid metabolism, we show that Fatostatin's anticancer properties can also be attributed to its inhibition of cell division. We analyzed the effect of SREBP activity inhibitors including Fatostatin, PF-429242, and Betulin on the cell cycle and determined that only Fatostatin possessed antimitotic properties. Fatostatin inhibited tubulin polymerization, arrested cells in mitosis, activated the spindle assembly checkpoint, and triggered mitotic catastrophe and reduced cell viability. Thus Fatostatin's ability to inhibit SREBP activity and cell division could prove beneficial in treating aggressive types of cancers such as glioblastomas that have elevated lipid metabolism and fast proliferation rates and often develop resistance to current anticancer therapies. PMID:27378817

  5. Cell-laden microengineered pullulan methacrylate hydrogels promote cell proliferation and 3D cluster formation

    PubMed Central

    Bae, Hojae; Ahari, Amir F.; Shin, Hyeongho; Nichol, Jason W.; Hutson, Che B.; Masaeli, Mahdokht; Kim, Su-Hwan; Aubin, Hug; Yamanlar, Seda; Khademhosseini, Ali

    2011-01-01

    The ability to encapsulate cells in three-dimensional (3D) environments is potentially of benefit for tissue engineering and regenerative medicine. In this paper, we introduce pullulan methacrylate (PulMA) as a promising hydrogel platform for creating cell-laden microscale tissues. The hydration and mechanical properties of PulMA were demonstrated to be tunable through modulation of the degree of methacrylation and gel concentration. Cells encapsulated in PulMA exhibited excellent viability. Interestingly, while cells did not elongate in PulMA hydrogels, cells proliferated and organized into clusters, the size of which could be controlled by the hydrogel composition. By mixing with gelatin methacrylate (GelMA), the biological properties of PulMA could be enhanced as demonstrated by cells readily attaching to, proliferating, and elongating within the PulMA/GelMA composite hydrogels. These data suggest that PulMA hydrogels could be useful for creating complex, cell-responsive microtissues, especially for applications that require controlled cell clustering and proliferation. PMID:21415929

  6. Downregulation of HDAC9 inhibits cell proliferation and tumor formation by inducing cell cycle arrest in retinoblastoma.

    PubMed

    Zhang, Yiting; Wu, Dan; Xia, Fengjie; Xian, Hongyu; Zhu, Xinyue; Cui, Hongjuan; Huang, Zhenping

    2016-04-29

    Histone deacetylase 9 (HDAC9) is a member of class II HDACs, which regulates a wide variety of normal and abnormal physiological functions. Recently, HDAC9 has been found to be overexpressed in some types of human cancers. However, the role of HDAC9 in retinoblastoma remains unclear. In this study, we found that HDAC9 was commonly expressed in retinoblastoma tissues and HDAC9 was overexpressed in prognostically poor retinoblastoma patients. Through knocking down HDAC9 in Y79 and WERI-Rb-1 cells, the expression level of HDAC9 was found to be positively related to cell proliferation in vitro. Further investigation indicated that knockdown HDAC9 could significantly induce cell cycle arrest at G1 phase in retinoblastoma cells. Western blot assay showed downregulation of HDAC9 could significantly decrease cyclin E2 and CDK2 expression. Lastly, xenograft study in nude mice showed that downregulation of HDAC9 inhibited tumor growth and development in vivo. Therefore, our results suggest that HDAC9 could serve as a novel potential therapeutic target in the treatment of retinoblastoma. PMID:27033599

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

    SciTech Connect

    Huang, Er-Wen; Xue, Sheng-Jiang; Li, Xiao-Yan; Xu, Suo-Wen; Cheng, Jian-Ding; Zheng, Jin-Xiang; Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong; Li, Jie; Liu, Chao

    2014-05-02

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

  8. DOCK2 regulates cell proliferation through Rac and ERK activation in B cell lymphoma

    SciTech Connect

    Wang, Lei; Nishihara, Hiroshi; Kimura, Taichi; Kato, Yasutaka; Tanino, Mishie; Nishio, Mitsufumi; Obara, Masato; Endo, Tomoyuki; Koike, Takao; Tanaka, Shinya

    2010-04-23

    DOCK2; a member of the CDM protein family, regulates cell motility and cytokine production through the activation of Rac in mammalian hematopoietic cells and plays a pivotal role in the modulation of the immune system. Here we demonstrated the alternative function of DOCK2 in hematopoietic tumor cells, especially in terms of its association with the tumor progression. Immunostaining for DOCK2 in 20 cases of human B cell lymphoma tissue specimens including diffuse large B cell lymphoma and follicular lymphoma revealed the prominent expression of DOCK2 in all of the lymphoma cells. DOCK2-knockdown (KD) of the B cell lymphoma cell lines, Ramos and Raji, using the lentiviral shRNA system presented decreased cell proliferation compared to the control cells. Furthermore, the tumor formation of DOCK2-KD Ramos cell in nude mice was significantly abrogated. Western blotting analysis and pull-down assay using GST-PAK-RBD kimeric protein suggested the presence of DOCK2-Rac-ERK pathway regulating the cell proliferation of these lymphoma cells. This is the first report to clarify the prominent role of DOCK2 in hematopoietic malignancy.

  9. A comparative study of colorimetric cell proliferation assays in immune cells.

    PubMed

    Koyanagi, Madoka; Kawakabe, So; Arimura, Yutaka

    2016-08-01

    Cell proliferation assays are basic and essential techniques for assessing cellular function. Various colorimetric assays, such as MTT-, WST-1-, and resazurin-based assays, are available; however, studies directly comparing the suitability of each method for immune cell proliferation are scarce. Thus, we aimed to determine the best reagent and its optimal conditions based on variables such as cell number range, stimulation dose, kinetics, and compatibility with the cell division assay using CFSE fluorescence dye which is able to directly monitor divided cells by flow cytometry. In the absence of stimulation, MTT solubilized with SDS (MTT-SDS) and resazurin appeared to accurately reflect the cell numbers in a linear fashion. On the other hand, WST-1 exhibited a higher stimulation index following strong stimulation, whereas MTT-SDS and resazurin exhibited a better sensitivity to weak stimulation. A longer duration for stimulation did not necessarily increase sensitivity. CFSE staining revealed incremental cell division in response to anti-CD3 antibody stimulation in a dose-dependent manner. The cell numbers indirectly estimated from cell division profiles were consistent with the dose-response curve in the absorbance of MTT-SDS and resazurin. The absorbance does not increase before cell division, irrespective of T cell activation status, suggesting that these reagents reflect the cell number but not the cellular volume. Collectively, resazurin and MTT-SDS seem to be more reliable than others, and thus appear applicable in various conditions for the immune cell experiments. PMID:26280992

  10. Expression of Nanog gene promotes NIH3T3 cell proliferation

    SciTech Connect

    Zhang Jingyu; Wang Xia; Chen Bing; Suo Guangli; Zhao Yanhong; Duan Ziyuan; Dai Jianwu . E-mail: jwdai@genetics.ac.cn

    2005-12-16

    Cells are the functional elements in tissue engineering and regenerative medicine. A large number of cells are usually needed for these purposes. However, there are numbers of limitations for in vitro cell proliferation. Nanog is an important self-renewal determinant in embryonic stem cells. However, it remains unknown whether Nanog will influence the cell cycle and cell proliferation of mature cells. In this study, we expressed Nanog in NIH3T3 cells and showed that expression of Nanog in NIH3T3 promoted cells to enter into S phase and enhanced cell proliferation. This suggests that Nanog gene might function in a similar fashion in mature cells as in ES cells. In addition, it may provide an approach for in vitro cell expansion.

  11. ETOH inhibits embryonic neural stem/precursor cell proliferation via PLD signaling

    SciTech Connect

    Fujita, Yuko; Hiroyama, Masami; Sanbe, Atsushi Yamauchi, Junji; Murase, Shoko; Tanoue, Akito

    2008-05-23

    While a mother's excessive alcohol consumption during pregnancy is known to have adverse effects on fetal neural development, little is known about the underlying mechanism of these effects. In order to investigate these mechanisms, we investigated the toxic effect of ethanol (ETOH) on neural stem/precursor cell (NSC) proliferation. In cultures of NSCs, phospholipase D (PLD) is activated following stimulation with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Exposure of NSCs to ETOH suppresses cell proliferation, while it has no effect on cell death. Phosphatidic acid (PA), which is a signaling messenger produced by PLD, reverses ETOH inhibition of NSC proliferation. Blocking the PLD signal by 1-butanol suppresses the proliferation. ETOH-induced suppression of NSC proliferation and the protective effect of PA for ETOH-induced suppression are mediated through extracellular signal-regulated kinase signaling. These results indicate that exposure to ETOH impairs NSC proliferation by altering the PLD signaling pathway.

  12. Effect of GINS2 on Proliferation and Apoptosis in Leukemic Cell Line

    PubMed Central

    Zhang, Xi; Zhong, Liang; Liu, Bei-Zhong; Gao, Yan-Jun; Gao, Yuan-Mei; Hu, Xiu-Xiu

    2013-01-01

    Although previous researches have demonstrated that GINS2 express abundantly and abnormally in many malignant solid tumors, such as breast cancer, melanoma and hepatic carcinoma. However, the role and precise molecular mechanism in acute promyelocytic leukemia (APL) are rarely reported. In this current study, we investigated the possible effect and particular mechanism of GINS2 in occurrence and development of APL. We synthesized interference plasmid targeted GINS2 successfully in vitro and also constructed recombinant adenovirus vector carrying GINS2 gene in order to down-regulate or up-regulate GINS2 expression from two aspects of positive and negative in APL. After siRNA were transfected into HL60 cells, both GINS2 expression level of mRNA and protein in interfering group were down-regulated when compared with control groups. Together, MTT and flow cytometry technology showed that cell growth was significantly inhibited. Moreover, the expression lever of Bax was distinctly increased whereas Bcl2 was dramatically decreased in transfected group. Further experiments revealed that down-regulation of GINS2 expression inhibited DNA replication and had a G2/M phase block in HL60 cells. What's more, ATM, CHK2, and P53 gene could involve in the pathogenic signaling pathways of HL60 cells when GINS2 gene was down-regulated. On the contrary, after HL60 cells were infected by recombinant adenovirus vector which contained GINS2 gene, we observed that over-expression of GINS2 could promote HL-60 cell proliferation. What's more, GINS2 might implicate a potential target for leukemia gene therapy. PMID:24273454

  13. Aquaporin 2-increased renal cell proliferation is associated with cell volume regulation.

    PubMed

    Di Giusto, Gisela; Flamenco, Pilar; Rivarola, Valeria; Fernández, Juan; Melamud, Luciana; Ford, Paula; Capurro, Claudia

    2012-12-01

    We have previously demonstrated that in renal cortical collecting duct cells (RCCD(1)) the expression of the water channel Aquaporin 2 (AQP2) raises the rate of cell proliferation. In this study, we investigated the mechanisms involved in this process, focusing on the putative link between AQP2 expression, cell volume changes, and regulatory volume decrease activity (RVD). Two renal cell lines were used: WT-RCCD(1) (not expressing aquaporins) and AQP2-RCCD(1) (transfected with AQP2). Our results showed that when most RCCD(1) cells are in the G(1)-phase (unsynchronized), the blockage of barium-sensitive K(+) channels implicated in rapid RVD inhibits cell proliferation only in AQP2-RCCD(1) cells. Though cells in the S-phase (synchronized) had a remarkable increase in size, this enhancement was higher and was accompanied by a significant down-regulation in the rapid RVD response only in AQP2-RCCD(1) cells. This decrease in the RVD activity did not correlate with changes in AQP2 function or expression, demonstrating that AQP2-besides increasing water permeability-would play some other role. These observations together with evidence implying a cell-sizing mechanism that shortens the cell cycle of large cells, let us to propose that during nutrient uptake, in early G(1), volume tends to increase but it may be efficiently regulated by an AQP2-dependent mechanism, inducing the rapid activation of RVD channels. This mechanism would be down-regulated when volume needs to be increased in order to proceed into the S-phase. Therefore, during cell cycle, a coordinated modulation of the RVD activity may contribute to accelerate proliferation of cells expressing AQP2. PMID:22786728

  14. Knockdown of DDX46 inhibits proliferation and induces apoptosis in esophageal squamous cell carcinoma cells.

    PubMed

    Li, Bin; Li, Yu-Min; He, Wen-Ting; Chen, Hao; Zhu, Hong-Wen; Liu, Tao; Zhang, Jian-Hua; Song, Tie-Niu; Zhou, Ya-Li

    2016-07-01

    Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal carcinoma and remains the leading cause of cancer-related death worldwide. DEAD-box RNA helicases play critical roles in cellular metabolism and in many cases have been implicated in cellular proliferation and neoplastic transformation. DDX46 belongs to DEAD-box helicase family, the expression pattern of DDX46 in ESCC tissues and the biologic role in ESCC progression have not been implicated previously. In this study, DDX46 expression in human ESCC and adjacent normal tissues were explored using immunohistochemistry, and ESCC cell lines compared with normal esophageal epithelium cell were quantified using real‑time PCR. Next, lentivirus-mediated RNA interference was applied to silence DDX46 in TE-1 and Eca-109 cells. Cell growth was monitored using high content screening. Cell viability was measured by MTT assay. Cell colony-forming capacity was measured by colony formation assay. Cell cycle progression and apoptosis were determined by flow cytometry. Further, the stress and apoptosis signaling antibody array kit was used to detect the changes of signaling molecules in TE-1 cells after DDX46 knockdown. We found that DDX46 was significantly upregulated in ESCC tissues and cells compared with normal tissues and cells. DDX46 knockdown led to decreased proliferation and increased apoptosis in TE-1 and Eca-109 cells. Moreover, DDX46 silencing resulted in apoptotic induction via decreased phosphorylation of Akt and IκBα, as well as negative regulation of NF-κB signaling. In conclusion, these results demonstrate that DDX46 knockdown inhibited cell growth, and induced apoptosis, suggest that DDX46 is critical for ESCC cells proliferation. In addition, this study provides a foundation for further study into the clinical potential diagnosis and novel therapeutic target for ESCC. PMID:27176873

  15. Piperlongumine Suppresses Proliferation of Human Oral Squamous Cell Carcinoma through Cell Cycle Arrest, Apoptosis and Senescence.

    PubMed

    Chen, San-Yuan; Liu, Geng-Hung; Chao, Wen-Ying; Shi, Chung-Sheng; Lin, Ching-Yen; Lim, Yun-Ping; Lu, Chieh-Hsiang; Lai, Peng-Yeh; Chen, Hau-Ren; Lee, Ying-Ray

    2016-01-01

    Oral squamous cell carcinoma (OSCC), an aggressive cancer originating in the oral cavity, is one of the leading causes of cancer deaths in males worldwide. This study investigated the antitumor activity and mechanisms of piperlongumine (PL), a natural compound isolated from Piper longum L., in human OSCC cells. The effects of PL on cell proliferation, the cell cycle, apoptosis, senescence and reactive oxygen species (ROS) levels in human OSCC cells were investigated. PL effectively inhibited cell growth, caused cell cycle arrest and induced apoptosis and senescence in OSCC cells. Moreover, PL-mediated anti-human OSCC behavior was inhibited by an ROS scavenger N-acetyl-l-cysteine (NAC) treatment, suggesting that regulation of ROS was involved in the mechanism of the anticancer activity of PL. These findings suggest that PL suppresses tumor growth by regulating the cell cycle and inducing apoptosis and senescence and is a potential chemotherapy agent for human OSCC cells. PMID:27120594

  16. Piperlongumine Suppresses Proliferation of Human Oral Squamous Cell Carcinoma through Cell Cycle Arrest, Apoptosis and Senescence

    PubMed Central

    Chen, San-Yuan; Liu, Geng-Hung; Chao, Wen-Ying; Shi, Chung-Sheng; Lin, Ching-Yen; Lim, Yun-Ping; Lu, Chieh-Hsiang; Lai, Peng-Yeh; Chen, Hau-Ren; Lee, Ying-Ray

    2016-01-01

    Oral squamous cell carcinoma (OSCC), an aggressive cancer originating in the oral cavity, is one of the leading causes of cancer deaths in males worldwide. This study investigated the antitumor activity and mechanisms of piperlongumine (PL), a natural compound isolated from Piper longum L., in human OSCC cells. The effects of PL on cell proliferation, the cell cycle, apoptosis, senescence and reactive oxygen species (ROS) levels in human OSCC cells were investigated. PL effectively inhibited cell growth, caused cell cycle arrest and induced apoptosis and senescence in OSCC cells. Moreover, PL-mediated anti-human OSCC behavior was inhibited by an ROS scavenger N-acetyl-l-cysteine (NAC) treatment, suggesting that regulation of ROS was involved in the mechanism of the anticancer activity of PL. These findings suggest that PL suppresses tumor growth by regulating the cell cycle and inducing apoptosis and senescence and is a potential chemotherapy agent for human OSCC cells. PMID:27120594

  17. GABA's Control of Stem and Cancer Cell Proliferation in Adult Neural and Peripheral Niches

    PubMed Central

    Young, Stephanie Z.; Bordey, Angélique

    2010-01-01

    Aside from traditional neurotransmission and regulation of secretion, γ-amino butyric acid (GABA) through GABAA receptors negatively regulates proliferation of pluripotent and neural stem cells in embryonic and adult tissue. There has also been evidence that GABAergic signaling and its control over proliferation is not only limited to the nervous system, but is widespread through peripheral organs containing adult stem cells. GABA has emerged as a tumor signaling molecule in the periphery that controls the proliferation of tumor cells and perhaps tumor stem cells. Here, we will discuss GABA's presence as a near-universal signal that may be altered in tumor cells resulting in modified mitotic activity. PMID:19509127

  18. Inhibitory effect of succinic acid on epithelial cell proliferation of colonic mucosa in rats.

    PubMed

    Inagaki, Akiko; Ichikawa, Hirofumi; Sakata, Takashi

    2007-08-01

    Microbial breakdown of carbohydrates in the large intestine mainly produces short-chain fatty acids (SCFA). SCFA stimulate epithelial cell proliferation of the digestive tract in vivo. Succinic acid sometimes accumulates in the colonic lumen. However, the effect of succinic acid on colonic epithelial cell proliferation is unknown. Thus, we planned to clarify the influence of succinic acid on colonic epithelial cell proliferation in vivo. We continuously administered infusate with or without succinic acid (100 mM) into the distal colon of rats for 6 d and measured accumulated mitosis per crypt of distal colon of these rats. Succinic acid infused into rat colons significantly inhibited colonic cell proliferation and reduced crypt size. These results clearly indicated the inhibitory effects of succinic acid on colonic epithelial cell proliferation in vivo. PMID:17934246

  19. MicroRNA-196b promotes cell proliferation and suppress cell differentiation in vitro

    SciTech Connect

    Cao, Donglin Hu, Liangshan; Lei, Da; Fang, Xiaolin; Zhang, Zhihong; Wang, Ting; Lin, Maorui; Huang, Jiwei; Yang, Huawen; Zhou, Xuan; Zhong, Limei

    2015-01-30

    Highlights: • miRNA-196b increases proliferation and blocks differentiation of progenitor cell. • miRNA-196b inhibits apoptosis and increases viability of cells lines. • Forced expression of miR-196b blocks the differentiation of THP1 induced by PMA. - Abstract: MicroRNA-196b (miR-196b) is frequently amplified and aberrantly overexpressed in acute leukemias. To investigate the role of miR-196b in acute leukemias, it has been observed that forced expression of this miRNA increases proliferation and inhibits apoptosis in human cell lines. More importantly, we show that this miRNA can significantly increase the colony-forming capacity of mouse normal bone marrow progenitor cells alone, as well as partially blocking the cells from differentiation. Taken together, our studies suggest that miRNA-196b may play an essential role in the development of MLL-associated leukemias through inhibiting cell differentiation and apoptosis, while promoting cell proliferation.

  20. DNA Replication Licensing Affects Cell Proliferation or Endoreplication in a Cell Type–Specific Manner

    PubMed Central

    del Mar Castellano, María; Boniotti, María Beatrice; Caro, Elena; Schnittger, Arp; Gutierrez, Crisanto

    2004-01-01

    In eukaryotic cells, the function of DNA replication licensing components (Cdc6 and Cdt1, among others) is crucial for cell proliferation and genome stability. However, little is known about their role in whole organisms and whether licensing control interfaces with differentiation and developmental programs. Here, we study Arabidopsis thaliana CDT1, its regulation, and the consequences of overriding licensing control. The availability of AtCDT1 is strictly regulated at two levels: (1) at the transcription level, by E2F and growth-arresting signals, and (2) posttranscriptionally, by CDK phosphorylation, a step that is required for its proteasome-mediated degradation. We also show that CDC6 and CDT1 are key targets for the coordination of cell proliferation, differentiation, and development. Indeed, altered CDT1 or CDC6 levels have cell type–specific effects in developing Arabidopsis plants: in leaf cells competent to divide, cell proliferation is stimulated, whereas in cells programmed to undergo differentiation-associated endoreplication rounds, extra endocycles are triggered. Thus, we propose that DNA replication licensing control is critical for the proper maintenance of proliferative potential, developmental programs, and morphogenetic patterns. PMID:15316110

  1. Structural and Functional Insight into Proliferating Cell Nuclear Antigen.

    PubMed

    Park, So Young; Jeong, Mi Suk; Han, Chang Woo; Yu, Hak Sun; Jang, Se Bok

    2016-04-28

    Proliferating cell nuclear antigen (PCNA) is a critical eukaryotic replication accessory factor that supports DNA binding in DNA processing, such as DNA replication, repair, and recombination. PCNA consists of three toroidal-shaped monomers that encircle doublestranded DNA. The diverse functions of PCNA may be regulated by its interactions with partner proteins. Many of the PCNA partner proteins generally have a conserved PCNAinteracting peptide (PIP) motif, located at the N- or C- terminal region. The PIP motif forms a 310 helix that enters into the hydrophobic groove produced by an interdomain-connecting loop, a central loop, and a C-terminal tail in the PCNA. Post-translational modification of PCNA also plays a critical role in regulation of its function and binding partner proteins. Structural and biochemical studies of PCNA-protein will be useful in designing therapeutic agents, as well as estimating the outcome of anticancer drug development. This review summarizes the characterization of eukaryotic PCNA in relation to the protein structures, functions, and modifications, and interaction with proteins. PMID:26699741

  2. The development of hepatic stellate cells in normal and abnormal human fetuses – an immunohistochemical study

    PubMed Central

    Loo, Christine K C; Pereira, Tamara N; Pozniak, Katarzyna N; Ramsing, Mette; Vogel, Ida; Ramm, Grant A

    2015-01-01

    The precise embryological origin and development of hepatic stellate cells is not established. Animal studies and observations on human fetuses suggest that they derive from posterior mesodermal cells that migrate via the septum transversum and developing diaphragm to form submesothelial cells beneath the liver capsule, which give rise to mesenchymal cells including hepatic stellate cells. However, it is unclear if these are similar to hepatic stellate cells in adults or if this is the only source of stellate cells. We have studied hepatic stellate cells by immunohistochemistry, in developing human liver from autopsies of fetuses with and without malformations and growth restriction, using cellular Retinol Binding Protein-1 (cRBP-1), Glial Fibrillary Acidic Protein (GFAP), and α-Smooth Muscle Actin (αSMA) antibodies, to identify factors that influence their development. We found that hepatic stellate cells expressing cRBP-1 are present from the end of the first trimester of gestation and reduce in density throughout gestation. They appear abnormally formed and variably reduced in number in fetuses with abnormal mesothelial Wilms Tumor 1 (WT1) function, diaphragmatic hernia and in ectopic liver nodules without mesothelium. Stellate cells showed similarities to intravascular cells and their presence in a fetus with diaphragm agenesis suggests they may be derived from circulating stem cells. Our observations suggest circulating stem cells as well as mesothelium can give rise to hepatic stellate cells, and that they require normal mesothelial function for their development. PMID:26265759

  3. Simulation of proliferation and differentiation of cells in a stem-cell niche

    NASA Astrophysics Data System (ADS)

    Zhdanov, Vladimir P.

    2008-10-01

    Stem-cell niches represent microscopic compartments formed of environmental cells that nurture stem cells and enable them to maintain tissue homeostasis. The spatio-temporal kinetics of proliferation and differentiation of cells in such niches depend on the specifics of the niche structure and on adhesion and communication between cells and may also be influenced by spatial constraints on cell division. We propose a generic lattice model, taking all these factors into account, and systematically illustrate their role. The model is motivated by the experimental data available for the niches located in the subventricular zone of adult mammalian brain. The general conclusions drawn from our Monte Carlo simulations are applicable to other niches as well. One of our main findings is that the kinetics under consideration are highly stochastic due to a relatively small number of cells proliferating and differentiating in a niche and the autocatalytic character of the symmetric cell division. In particular, the kinetics exhibit huge stochastic bursts especially if the adhesion between cells is taken into account. In addition, the results obtained show that despite the small number of cells present in stem-cell niches, their arrangement can be predetermined to appreciable extent provided that the adhesion of different cells is different so that they tend to segregate.

  4. Stimulation of TM3 Leydig cell proliferation via GABAA receptors: A new role for testicular GABA

    PubMed Central

    Geigerseder, Christof; Doepner, Richard FG; Thalhammer, Andrea; Krieger, Annette; Mayerhofer, Artur

    2004-01-01

    The neurotransmitter gamma-aminobutyric acid (GABA) and subtypes of GABA receptors were recently identified in adult testes. Since adult Leydig cells possess both the GABA biosynthetic enzyme glutamate decarboxylase (GAD), as well as GABAA and GABAB receptors, it is possible that GABA may act as auto-/paracrine molecule to regulate Leydig cell function. The present study was aimed to examine effects of GABA, which may include trophic action. This assumption is based on reports pinpointing GABA as regulator of proliferation and differentiation of developing neurons via GABAA receptors. Assuming such a role for the developing testis, we studied whether GABA synthesis and GABA receptors are already present in the postnatal testis, where fetal Leydig cells and, to a much greater extend, cells of the adult Leydig cell lineage proliferate. Immunohistochemistry, RT-PCR, Western blotting and a radioactive enzymatic GAD assay evidenced that fetal Leydig cells of five-six days old rats possess active GAD protein, and that both fetal Leydig cells and cells of the adult Leydig cell lineage possess GABAA receptor subunits. TM3 cells, a proliferating mouse Leydig cell line, which we showed to possess GABAA receptor subunits by RT-PCR, served to study effects of GABA on proliferation. Using a colorimetric proliferation assay and Western Blotting for proliferating cell nuclear antigen (PCNA) we demonstrated that GABA or the GABAA agonist isoguvacine significantly increased TM3 cell number and PCNA content in TM3 cells. These effects were blocked by the GABAA antagonist bicuculline, implying a role for GABAA receptors. In conclusion, GABA increases proliferation of TM3 Leydig cells via GABAA receptor activation and proliferating Leydig cells in the postnatal rodent testis bear a GABAergic system. Thus testicular GABA may play an as yet unrecognized role in the development of Leydig cells during the differentiation of the testicular interstitial compartment. PMID:15040802

  5. Baicalin inhibits PDGF-induced proliferation and migration of airway smooth muscle cells

    PubMed Central

    Yang, Guang; Li, Jian-Qiang; Bo, Jian-Ping; Wang, Bei; Tian, Xin-Rui; Liu, Tan-Zhen; Liu, Zhuo-La

    2015-01-01

    Airway smooth muscle (ASM) cell proliferation and migration play important roles in airway remodeling in asthma. In vitro platelet-derived growth factor (PDGF) induced ASM cell proliferation and migration. Baicalin is one of flavonoid extracts from Scutellaria baicalensis, which has an anti-asthma effect. However, little is known about its role in PDGF-induced proliferation and migration in rat ASM (RASM) cells. In this study, we aimed to investigate the effects of baicalin on PDGF-induced RASM cell proliferation and migration. We also identified the signaling pathway by which baicalin influences RASM cell proliferation and migration. In the current study, we demonstrated that baicalin suppressed PDGF-induced RASM cell proliferation, arrested PDGF-induced cell-cycle progression. It also suppressed PDGF-induced RASM cell migration. Furthermore, baicalin suppressed PDGF-induced expression of phosphorylated p38, ERK1/2 and JNK in RASM cells. In summary, our study is the first to show that baicalin pretreatment can significantly inhibit PDGF-induced RASM cell proliferation and migration by suppressing the MAPK signaling pathway, and baicalin may be a useful chemotherapeutic agent for asthma. PMID:26884970

  6. Oxidized Lipoprotein as a Major Vessel Cell Proliferator in Oxidized Human Serum

    PubMed Central

    Noguchi, Noriko

    2016-01-01

    Oxidative stress is correlated with the incidence of several diseases such as atherosclerosis and cancer, and oxidized biomolecules have been determined as biomarkers of oxidative stress; however, the detailed molecular relationship between generated oxidation products and the promotion of diseases has not been fully elucidated. In the present study, to clarify the role of serum oxidation products in vessel cell proliferation, which is related to the incidence of atherosclerosis and cancer, the major vessel cell proliferator in oxidized human serum was investigated. Oxidized human serum was prepared by free radical exposure, separated using gel chromatography, and then each fraction was added to several kinds of vessel cells including endothelial cells and smooth muscle cells. It was found that a high molecular weight fraction in oxidized human serum specifically induced vessel cell proliferation. Oxidized lipids were contained in this high molecular weight fraction, while cell proliferation activity was not observed in oxidized lipoprotein-deficient serum. Oxidized low-density lipoproteins induced vessel cell proliferation in a concentration-dependent manner. Taken together, these results indicate that oxidized lipoproteins containing lipid oxidation products function as a major vessel cell proliferator in oxidized human serum. These findings strongly indicate the relevance of determination of oxidized lipoproteins and lipid oxidation products in the diagnosis of vessel cell proliferation-related diseases such as atherosclerosis and cancer. PMID:27483438

  7. Effect of mitoxantrone on proliferation dynamics and cell-cycle progression.

    PubMed

    Khan, Shahper N; Lal, Sunil K; Kumar, Purnima; Khan, Asad U

    2010-12-01

    MTX (mitoxantrone), an anti-tumour antibiotic, is known to cause cell death by intercalating the DNA bases. But how it interferes with the cellular proliferation is not well known. Hence, in the present study, we have tried to evaluate the interaction of this drug using proliferation dynamics to gain a better understanding of MTX's antineoplastic action. Inhibition of proliferation by these drugs was detected by evaluating its effect on cell proliferation and growth curve of the cells. MTX was also found to affect the cell viability and, thereby, cell physiology. Typical apoptotic morphologies such as condensation of nuclei and membrane permeabilization were observed through CLSM (confocal laser scanning microscopy) and fluorescence spectroscopy, which implicates commitment to cell death. Cell-cycle distribution was measured by flow cytometric measurements. The analysis demonstrated significant cell-cycle arrest on MTX treatment. Inhibition of lacZ gene expression was also observed on drug treatment, which implicates its interaction with gene expression. PMID:19951261

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

    PubMed

    Umka Welbat, Jariya; Sirichoat, Apiwat; Chaijaroonkhanarak, Wunnee; Prachaney, Parichat; Pannangrong, Wanassanun; Pakdeechote, Poungrat; Sripanidkulchai, Bungorn; Wigmore, Peter

    2016-01-01

    Valproic acid (VPA) is commonly prescribed as an anticonvulsant and mood stabilizer used in the treatment of epilepsy and bipolar disorder. A recent study has demonstrated that VPA reduces histone deacetylase (HDAC) activity, an action which is believed to contribute to the effects of VPA on neural stem cell proliferation and differentiation which may explain the cognitive impairments produced in rodents and patients. Asiatic acid is a triterpenoid derived from the medicinal plant Centella asiatica. Our previous study has shown that Asiatic acid improves working spatial memory and increases cell proliferation in the sub granular zone of the hippocampal dentate gyrus. In the present study we investigate the effects of Asiatic acid in preventing the memory and cellular effects of VPA. Male Spraque-Dawley rats were orally administered Asiatic acid (30 mg/kg/day) for 28 days, while VPA-treated animals received injections of VPA (300 mg/kg) twice a day from Day 15 to Day 28 for 14 days. Spatial memory was determined using the novel object location (NOL) test and hippocampal cell proliferation and survival was quantified by immuostaining for Ki-67 and Bromodeoxyuridine (BrdU), respectively. The results showed that VPA-treated animals were unable to discriminate between objects in familiar and novel locations. Moreover, VPA significantly reduced numbers of Ki-67 and BrdU positive cells. These results indicate that VPA treatment caused impairments of spatial working memory, cell proliferation and survival in the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG). However, these abnormalities were restored to control levels by co-treatment with Asiatic acid. These data demonstrate that Asiatic acid could prevent the spatial memory and neurogenesis impairments caused by VPA. PMID:27213437

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

    PubMed Central

    Umka Welbat, Jariya; Sirichoat, Apiwat; Chaijaroonkhanarak, Wunnee; Prachaney, Parichat; Pannangrong, Wanassanun; Pakdeechote, Poungrat; Sripanidkulchai, Bungorn; Wigmore, Peter

    2016-01-01

    Valproic acid (VPA) is commonly prescribed as an anticonvulsant and mood stabilizer used in the treatment of epilepsy and bipolar disorder. A recent study has demonstrated that VPA reduces histone deacetylase (HDAC) activity, an action which is believed to contribute to the effects of VPA on neural stem cell proliferation and differentiation which may explain the cognitive impairments produced in rodents and patients. Asiatic acid is a triterpenoid derived from the medicinal plant Centella asiatica. Our previous study has shown that Asiatic acid improves working spatial memory and increases cell proliferation in the sub granular zone of the hippocampal dentate gyrus. In the present study we investigate the effects of Asiatic acid in preventing the memory and cellular effects of VPA. Male Spraque-Dawley rats were orally administered Asiatic acid (30 mg/kg/day) for 28 days, while VPA-treated animals received injections of VPA (300 mg/kg) twice a day from Day 15 to Day 28 for 14 days. Spatial memory was determined using the novel object location (NOL) test and hippocampal cell proliferation and survival was quantified by immuostaining for Ki-67 and Bromodeoxyuridine (BrdU), respectively. The results showed that VPA-treated animals were unable to discriminate between objects in familiar and novel locations. Moreover, VPA significantly reduced numbers of Ki-67 and BrdU positive cells. These results indicate that VPA treatment caused impairments of spatial working memory, cell proliferation and survival in the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG). However, these abnormalities were restored to control levels by co-treatment with Asiatic acid. These data demonstrate that Asiatic acid could prevent the spatial memory and neurogenesis impairments caused by VPA. PMID:27213437

  10. The Chromatin Regulator Brpf1 Regulates Embryo Development and Cell Proliferation*

    PubMed Central

    You, Linya; Yan, Kezhi; Zou, Jinfeng; Zhao, Hong; Bertos, Nicholas R.; Park, Morag; Wang, Edwin; Yang, Xiang-Jiao

    2015-01-01

    With hundreds of chromatin regulators identified in mammals, an emerging issue is how they modulate biological and pathological processes. BRPF1 (bromodomain- and PHD finger-containing protein 1) is a unique chromatin regulator possessing two PHD fingers, one bromodomain and a PWWP domain for recognizing multiple histone modifications. In addition, it binds to the acetyltransferases MOZ, MORF, and HBO1 (also known as KAT6A, KAT6B, and KAT7, respectively) to promote complex formation, restrict substrate specificity, and enhance enzymatic activity. We have recently showed that ablation of the mouse Brpf1 gene causes embryonic lethality at E9.5. Here we present systematic analyses of the mutant animals and demonstrate that the ablation leads to vascular defects in the placenta, yolk sac, and embryo proper, as well as abnormal neural tube closure. At the cellular level, Brpf1 loss inhibits proliferation of embryonic fibroblasts and hematopoietic progenitors. Molecularly, the loss reduces transcription of a ribosomal protein L10 (Rpl10)-like gene and the cell cycle inhibitor p27, and increases expression of the cell-cycle inhibitor p16 and a novel protein homologous to Scp3, a synaptonemal complex protein critical for chromosome association and embryo survival. These results uncover a crucial role of Brpf1 in controlling mouse embryo development and regulating cellular and gene expression programs. PMID:25773539

  11. Histone acetyltransferase PCAF is required for Hedgehog-Gli-dependent transcription and cancer cell proliferation.

    PubMed

    Malatesta, Martina; Steinhauer, Cornelia; Mohammad, Faizaan; Pandey, Deo P; Squatrito, Massimo; Helin, Kristian

    2013-10-15

    The Hedgehog (Hh) signaling pathway plays an important role in embryonic patterning and development of many tissues and organs as well as in maintaining and repairing mature tissues in adults. Uncontrolled activation of the Hh-Gli pathway has been implicated in developmental abnormalities as well as in several cancers, including brain tumors like medulloblastoma and glioblastoma. Inhibition of aberrant Hh-Gli signaling has, thus, emerged as an attractive approach for anticancer therapy; however, the mechanisms that mediate Hh-Gli signaling in vertebrates remain poorly understood. Here, we show that the histone acetyltransferase PCAF/KAT2B is an important factor of the Hh pathway. Specifically, we show that PCAF depletion impairs Hh activity and reduces expression of Hh target genes. Consequently, PCAF downregulation in medulloblastoma and glioblastoma cells leads to decreased proliferation and increased apoptosis. In addition, we found that PCAF interacts with GLI1, the downstream effector in the Hh-Gli pathway, and that PCAF or GLI1 loss reduces the levels of H3K9 acetylation on Hh target gene promoters. Finally, we observed that PCAF silencing reduces the tumor-forming potential of neural stem cells in vivo. In summary, our study identified the acetyltransferase PCAF as a positive cofactor of the Hh-Gli signaling pathway, leading us to propose PCAF as a candidate therapeutic target for the treatment of patients with medulloblastoma and glioblastoma. PMID:23943798

  12. The chromatin regulator Brpf1 regulates embryo development and cell proliferation.

    PubMed

    You, Linya; Yan, Kezhi; Zou, Jinfeng; Zhao, Hong; Bertos, Nicholas R; Park, Morag; Wang, Edwin; Yang, Xiang-Jiao

    2015-05-01

    With hundreds of chromatin regulators identified in mammals, an emerging issue is how they modulate biological and pathological processes. BRPF1 (bromodomain- and PHD finger-containing protein 1) is a unique chromatin regulator possessing two PHD fingers, one bromodomain and a PWWP domain for recognizing multiple histone modifications. In addition, it binds to the acetyltransferases MOZ, MORF, and HBO1 (also known as KAT6A, KAT6B, and KAT7, respectively) to promote complex formation, restrict substrate specificity, and enhance enzymatic activity. We have recently showed that ablation of the mouse Brpf1 gene causes embryonic lethality at E9.5. Here we present systematic analyses of the mutant animals and demonstrate that the ablation leads to vascular defects in the placenta, yolk sac, and embryo proper, as well as abnormal neural tube closure. At the cellular level, Brpf1 loss inhibits proliferation of embryonic fibroblasts and hematopoietic progenitors. Molecularly, the loss reduces transcription of a ribosomal protein L10 (Rpl10)-like gene and the cell cycle inhibitor p27, and increases expression of the cell-cycle inhibitor p16 and a novel protein homologous to Scp3, a synaptonemal complex protein critical for chromosome association and embryo survival. These results uncover a crucial role of Brpf1 in controlling mouse embryo development and regulating cellular and gene expression programs. PMID:25773539

  13. Angiomotin promotes renal epithelial and carcinoma cell proliferation by retaining the nuclear YAP

    PubMed Central

    Lv, Meng; Li, Shuting; Luo, Changqin; Zhang, Xiaoman; Shen, Yanwei; Sui, YanXia; Wang, Fan; Wang, Xin; Yang, Jiao; Liu, Peijun; Yang, Jin

    2016-01-01

    Renal cell carcinoma (RCC) is one of the common tumors in the urinary system without effective therapies. Angiomotin (Amot) can interact with Yes-associated protein (YAP) to either stimulate or inhibit YAP activity, playing a potential role in cell proliferation. However, the role of Amot in regulating the proliferation of renal epithelial and RCC cells is unknown. Here, we show that Amot is expressed predominantly in the nucleus of RCC cells and tissues, and in the cytoplasm and nucleus of renal epithelial cells and paracancerous tissues. Furthermore, Amot silencing inhibited proliferation of HK-2 and 786-O cells while Amot upregulation promoted proliferation of ACHN cells. Interestingly, the location of Amot and YAP in RCC clinical samples and cells was similar. Amot interacted with YAP in HK-2 and 786-O cells, particularly in the nucleus. Moreover, Amot silencing mitigated the levels of nuclear YAP in HK-2 and 786-O cells and reduced YAP-related CTGF and Cyr61 expression in 786-O cells. Amot upregulation slightly increased the nuclear YAP and YAP-related gene expression in ACHN cells. Finally, enhanced YAP expression restored proliferation of Amot-silencing 786-O cells. Together, these data indicate that Amot is crucial for the maintenance of nuclear YAP to promote renal epithelial and RCC proliferation. PMID:26848622

  14. Inhibitory effect of MyoD on the proliferation of breast cancer cells

    PubMed Central

    CAI, CHANGJING; QIN, XIAOQUN; WU, ZIYI; SHEN, QIXIA; YANG, WENQIAN; ZHANG, SHUJUN; DUAN, JINLING; LIANG, FENGLAN; LIU, CHI

    2016-01-01

    Skeletal muscle is rich in lymphatic vessels, with an abundant blood supply, and it is an infrequent site of cancer metastasis. Previous studies have demonstrated that enhanced secretion of MyoD may occur when skeletal muscle is injured or becomes cancerous. It was hypothesized that MyoD may act as an endogenous cytokine to inhibit the proliferation of cancer cells. To verify the possible effect of this protein on tumor cell proliferation, C2C12 mouse skeletal muscle cells and 4T1 mouse breast cancer cells were co-cultured using embedded Transwell plates. Following co-culture, cell cycle analysis revealed that C2C12 muscle cells were able to inhibit the proliferation of the breast cancer cells. Subsequently, MyoD was silenced in C2C12 cells to assess its effect on 4T1 cell proliferation. Following co-culture with MyoD-silenced cells, a 5-ethynyl-20-deoxyuridine assay indicated that MyoD silencing prevented the reduction in proliferation of 4T1 cells induced by untransfected C2C12 cells. In summary, the results indicated that MyoD inhibits the proliferation of breast cancer cells and may be a tumor suppressor factor. PMID:27284360

  15. Relationship between pulmonary and cardiac abnormalities in sickle cell disease: implications for the management of patients

    PubMed Central

    Maioli, Maria Christina Paixão; Soares, Andrea Ribeiro; Bedirian, Ricardo; Alves, Ursula David; de Lima Marinho, Cirlene; Lopes, Agnaldo José

    2015-01-01

    Objective To evaluate the association between clinical, pulmonary, and cardiovascular findings in patients with sickle cell disease and, secondarily, to compare these findings between sickle cell anemia patients and those with other sickle cell diseases. Methods Fifty-nine adults were included in this cross-sectional study; 47 had sickle cell anemia, and 12 had other sickle cell diseases. All patients underwent pulmonary function tests, chest computed tomography, and echocardiography. Results Abnormalities on computed tomography, echocardiography, and pulmonary function tests were observed in 93.5%, 75.0%; and 70.2% of patients, respectively. A higher frequency of restrictive abnormalities was observed in patients with a history of acute chest syndrome (85% vs. 21.6%; p-value < 0.0001) and among patients with increased left ventricle size (48.2% vs. 22.2%; p-value = 0.036), and a higher frequency of reduced respiratory muscle strength was observed in patients with a ground-glass pattern (33.3% vs. 4.3%; p-value = 0.016). Moreover, a higher frequency of mosaic attenuation was observed in patients with elevated tricuspid regurgitation velocity (61.1% vs. 24%; p-value = 0.014). Compared to patients with other sickle cell diseases, sickle cell anemia patients had suffered increased frequencies of acute pain episodes, and acute chest syndrome, and exhibited mosaic attenuation on computed tomography, and abnormalities on echocardiography. Conclusion A significant interrelation between abnormalities of the pulmonary and cardiovascular systems was observed in sickle cell disease patients. Furthermore, the severity of the cardiopulmonary parameters among patients with sickle cell anemia was greater than that of patients with other sickle cell diseases. PMID:26969771

  16. Thymic B cells promote thymus-derived regulatory T cell development and proliferation.

    PubMed

    Lu, Fang-Ting; Yang, Wei; Wang, Yin-Hu; Ma, Hong-Di; Tang, Wei; Yang, Jing-Bo; Li, Liang; Ansari, Aftab A; Lian, Zhe-Xiong

    2015-07-01

    Thymic CD4(+) FoxP3(+) regulatory T (Treg) cells are critical for the development of immunological tolerance and immune homeostasis and requires contributions of both thymic dendritic and epithelial cells. Although B cells have been reported to be present within the thymus, there has not hitherto been a definition of their role in immune cell development and, in particular, whether or how they contribute to the Treg cellular thymic compartment. Herein, using both phenotypic and functional approaches, we demonstrate that thymic B cells contribute to the maintenance of thymic Treg cells and, using an in vitro culture system, demonstrate that thymic B cells contribute to the size of the thymic Treg compartment via cell-cell MHC II contact and the involvement of two independent co-stimulatory pathways that include interactions between the CD40/CD80/CD86 co-stimulatory molecules. Our data also suggest that thymic B cells promote the generation of thymic Treg cell precursors (pre-Treg cells), but not the conversion of FoxP3(+) Treg cells from pre-Treg cells. In addition, thymic B cells directly promote the proliferation of thymic Treg cells that is MHC II contact dependent with a minimal if any role for co-stimulatory molecules including CD40/CD80/CD86. Both pathways are independent of TGFβ. In conclusion, we rigorously define the critical role of thymic B cells in the development of thymic Treg cells from non-Treg to precursor stage and in the proliferation of mature thymic Treg cells. PMID:26071985

  17. MicroRNA-10b promotes nucleus pulposus cell proliferation through RhoC-Akt pathway by targeting HOXD10 in intervetebral disc degeneration.

    PubMed

    Yu, Xin; Li, Zheng; Shen, Jianxiong; Wu, William K K; Liang, Jinqian; Weng, Xisheng; Qiu, Guixing

    2013-01-01

    Aberrant proliferation of nucleus pulposus cell is implicated in the pathogenesis of intervertebral disc degeneration. Recent findings revealed that microRNAs, a class of small noncoding RNAs, could regulate cell proliferation in many pathological conditions. Here, we showed that miR-10b was dramatically upregulated in degenerative nucleus pulposus tissues when compared with nucleus pulposus tissues isolated from patients with idiopathic scoliosis. Moreover, miR-10b levels were associated with disc degeneration grade and downregulation of HOXD10. In cultured nucleus pulposus cells, miR-10b overexpression stimulated cell proliferation with concomitant translational inhibition of HOXD10 whereas restored expression of HOXD10 reversed the mitogenic effect of miR-10b. MiR-10b-mediated downregulation of HOXD10 led to increased RhoC expression and Akt phosphorylation. Either knockdown of RhoC or inhibition of Akt abolished the effect of miR-10b on nucleus pulposus cell proliferation. Taken together, aberrant miR-10b upregulation in intervertebral disc degeneration could contribute to abnormal nucleus pulposus cell proliferation through derepressing the RhoC-Akt pathway by targeting HOXD10. Our study also underscores the potential of miR-10b and the RhoC-Akt pathway as novel therapeutic targets in intervertebral disc degeneration. PMID:24376640

  18. MicroRNA-10b Promotes Nucleus Pulposus Cell Proliferation through RhoC-Akt Pathway by Targeting HOXD10 in Intervetebral Disc Degeneration

    PubMed Central

    Shen, Jianxiong; Wu, William K. K.; Liang, Jinqian; Weng, Xisheng; Qiu, Guixing

    2013-01-01

    Aberrant proliferation of nucleus pulposus cell is implicated in the pathogenesis of intervertebral disc degeneration. Recent findings revealed that microRNAs, a class of small noncoding RNAs, could regulate cell proliferation in many pathological conditions. Here, we showed that miR-10b was dramatically upregulated in degenerative nucleus pulposus tissues when compared with nucleus pulposus tissues isolated from patients with idiopathic scoliosis. Moreover, miR-10b levels were associated with disc degeneration grade and downregulation of HOXD10. In cultured nucleus pulposus cells, miR-10b overexpression stimulated cell proliferation with concomitant translational inhibition of HOXD10 whereas restored expression of HOXD10 reversed the mitogenic effect of miR-10b. MiR-10b-mediated downregulation of HOXD10 led to increased RhoC expression and Akt phosphorylation. Either knockdown of RhoC or inhibition of Akt abolished the effect of miR-10b on nucleus pulposus cell proliferation. Taken together, aberrant miR-10b upregulation in intervertebral disc degeneration could contribute to abnormal nucleus pulposus cell proliferation through derepressing the RhoC-Akt pathway by targeting HOXD10. Our study also underscores the potential of miR-10b and the RhoC-Akt pathway as novel therapeutic targets in intervertebral disc degeneration. PMID:24376640

  19. MECHANISMS INVOLVED IN THE ENHANCED SUSCEPTIBILITY OF SENESCENT RATS TO THE HEPATOCARCINOGENIC EFFECT OF PEROXISOME PROLIFERATORS: ROLE OF PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR ALPHA (PPARA), CELL PROLIFERATION AND OXIDATIVE STRESS

    EPA Science Inventory

    Mechanisms involved in the ENHANCED SUSCEPTIBILITY of SENESCENT Rats TO THE HEPATOCARCINOGENIC EFFECT OF PEROXISOME PROLIFERATORS: Role of peroxisome proliferator-activated receptor alpha (PPARa), cell proliferation and oxidative stress

    Jihan A. Youssef1, Pierre Ammann2, B...

  20. Burden of cytogenetically abnormal plasma cells in light chain amyloidosis and their prognostic relevance.

    PubMed

    Kim, Seon Young; Im, Kyongok; Park, Si Nae; Kim, Jung-Ah; Yoon, Sung-Soo; Lee, Dong Soon

    2016-05-01

    We performed cytoplasmic fluorescence in situ hybridization assays of light chain amyloidosis (AL). In total, 234 patients were enrolled: 28 patients with AL, 24 with monoclonal gammopathy of undetermined significance (MGUS), and 182 with multiple myeloma (MM). Chromosomal abnormalities were detected in 13 of 22 (59%) AL patients without MM. All 13 patients demonstrated IGH rearrangement, and t(11;14)/IGH-CCND1 was most frequent (32%). Chromosome gain was not observed in AL patients without MM. These findings were dissimilar to findings in MGUS patients, in whom trisomy 9 was the most frequent abnormality. Of 6 AL patients with MM, 5 (83%) patients had cytogenetic abnormalities: 1q gain (4/6, 67%), gains of chromosome 9 (3/6, 50%), IGH rearrangement and RB1 (13q) deletions (2/6 each, 33%). The percentage of clonal plasma cells among total plasma cells was variable (median, 75%; range, 16-100%) for AL patients without MM, which was lower than the results for MM patients (median 100%). The overall survival of AL patients without MM was not significantly different according to the presence of cytogenetic abnormalities (P=0.510). In summary, among Korean AL patients, IGH rearrangement was the most frequent cytogenetic abnormality and cytogenetic aberration patterns differ compared with MGUS and MM patients. PMID:27015231

  1. Dynamic assessment of cell viability, proliferation and migration using real time cell analyzer system (RTCA).

    PubMed

    Roshan Moniri, Mani; Young, Ada; Reinheimer, Kelsey; Rayat, Jarrett; Dai, Long-Jun; Warnock, Garth L

    2015-03-01

    Cell viability and cell migration capacities are critical parameters for cell culture-related studies. It is essential to monitor the dynamic changes of cell properties under various co-culture conditions to our better understanding of their behaviours and characteristics. The real time cell analyzer (RTCA, xCELLigence, Roche) is an impedance-based technology that can be used for label-free and real-time monitoring of cell properties, such as cell adherence, proliferation, migration and cytotoxicity. The practicality of this system has been proven in our recent cancer studies. In the present method, we intend to use co-cultures of pancreatic cancer cells (HP62) and mesenchymal stem cells to describe in detail, the procedures and benefits of RTCA. PMID:24443077

  2. Neisseria lactamica selectively induces mitogenic proliferation of the naive B cell pool via cell surface Ig.

    PubMed

    Vaughan, Andrew T; Brackenbury, Louise S; Massari, Paola; Davenport, Victoria; Gorringe, Andrew; Heyderman, Robert S; Williams, Neil A

    2010-09-15

    Neisseria lactamica is a commensal bacteria that colonizes the human upper respiratory tract mucosa during early childhood. In contrast to the closely related opportunistic pathogen Neisseria meningitidis, there is an absence of adaptive cell-mediated immunity to N. lactamica during the peak age of carriage. Instead, outer membrane vesicles derived from N. lactamica mediate a B cell-dependent proliferative response in mucosal mononuclear cells that is associated with the production of polyclonal IgM. We demonstrate in this study that this is a mitogenic human B cell response that occurs independently of T cell help and any other accessory cell population. The ability to drive B cell proliferation is a highly conserved property and is present in N. lactamica strains derived from diverse clonal complexes. CFSE staining of purified human tonsillar B cells demonstrated that naive IgD(+) and CD27(-) B cells are selectively induced to proliferate by outer membrane vesicles, including the innate CD5(+) subset. Neither purified lipooligosaccharide nor PorB from N. lactamica is likely to be responsible for this activity. Prior treatment of B cells with pronase to remove cell-surface Ig or treatment with BCR-specific Abs abrogated the proliferative response to N. lactamica outer membrane vesicles, suggesting that this mitogenic response is dependent upon the BCR. PMID:20709949

  3. Astaxanthin Inhibits Proliferation of Human Gastric Cancer Cell Lines by Interrupting Cell Cycle Progression

    PubMed Central

    Kim, Jung Ha; Park, Jong-Jae; Lee, Beom Jae; Joo, Moon Kyung; Chun, Hoon Jai; Lee, Sang Woo; Bak, Young-Tae

    2016-01-01

    Background/Aims Astaxanthin is a carotenoid pigment that has antioxidant, antitumoral, and anti-inflammatory properties. In this in vitro study, we investigated the mechanism of anticancer effects of astaxanthin in gastric carcinoma cell lines. Methods The human gastric adenocarcinoma cell lines AGS, KATO-III, MKN-45, and SNU-1 were treated with various concentrations of astaxanthin. A cell viability test, cell cycle analysis, and immunoblotting were performed. Results The viability of each cancer cell line was suppressed by astaxanthin in a dose-dependent manner with significantly decreased proliferation in KATO-III and SNU-1 cells. Astaxanthin increased the number of cells in the G0/G1 phase but reduced the proportion of S phase KATO-III and SNU-1 cells. Phosphorylated extracellular signal-regulated kinase (ERK) was decreased in an inverse dose-dependent correlation with astaxanthin concentration, and the expression of p27kip-1 increased the KATO-III and SNU-1 cell lines in an astaxanthin dose-dependent manner. Conclusions Astaxanthin inhibits proliferation by interrupting cell cycle progression in KATO-III and SNU-1 gastric cancer cells. This may be caused by the inhibition of the phosphorylation of ERK and the enhanced expression of p27kip-1. PMID:26470770

  4. 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

  5. Role of clot-associated (-derived) thrombin in cell proliferation induced by fibrin clots in vitro

    PubMed Central

    Gandossi, E; Lunven, C; Berry, C N

    2000-01-01

    Thrombin is a potent mitogenic agent. Clot-associated thrombin retains its amidolytic and pro-aggregant activity. We therefore studied the ability of fibrin clots to induce proliferation in CCL39 cells (Chinese hamster lung fibroblasts), in the absence and presence of the thrombin inhibitors PPACK, recombinant hirudin (rHV2 Lys47) and heparin:antithrombin III. Fibrin clots incubated for 48 h with CCL39 cells led to significant cell proliferation, which was dependent on the concentration of thrombin used to prepare the clots. Thus, clots prepared with 91 nmol l−1 thrombin produced a similar proliferation (231±21%) to that obtained with 50 nmol l−1 thrombin in solution (213±29%). Rabbit plasma clots led to a 499±41% increase in cell number under identical conditions. Fibrin clot-induced cell proliferation was inhibited by all three thrombin inhibitors with no difference in IC50 values compared to those obtained against thrombin in solution, suggesting that cell proliferation be due to thrombin leaching from the clots. We found a time-dependent increase in thrombin release from the clots attaining a plateau at 24 h (∼61% of the total thrombin used in clot formation). Clots separated from the cells using porous cell culture chamber inserts led to similar proliferation to that of clots in contact with the cells. Thus fibrin-clot induced CCL39 proliferation is due to thrombin released from the clots. PMID:10696104

  6. Abnormal bone marrow distribution following unsuccessful hip replacement: a potential confusion on white cell scanning.

    PubMed

    Cunningham, D A

    1991-01-01

    A case is presented in which a grossly abnormal distribution of bone marrow following failed hip replacement would have led to the false diagnosis of osteomyelitis. The value of combining bone marrow scanning with indium white cell scanning in possible osteomyelitis is emphasised. PMID:2019282

  7. Cdk4 functions in multiple cell types to control Drosophila intestinal stem cell proliferation and differentiation

    PubMed Central

    Adlesic, Mojca; Frei, Christian; Frew, Ian J.

    2016-01-01

    ABSTRACT The proliferation of intestinal stem cells (ISCs) and differentiation of enteroblasts to form mature enteroendocrine cells and enterocytes in the Drosophila intestinal epithelium must be tightly regulated to maintain homeostasis. We show that genetic modulation of CyclinD/Cdk4 activity or mTOR-dependent signalling cell-autonomously regulates enterocyte growth, which influences ISC proliferation and enteroblast differentiation. Increased enterocyte growth results in higher numbers of ISCs and defective enterocyte growth reduces ISC abundance and proliferation in the midgut. Adult midguts deficient for Cdk4 show severe disruption of intestinal homeostasis characterised by decreased ISC self-renewal, enteroblast differentiation defects and low enteroendocrine cell and enterocyte numbers. The ISC/enteroblast phenotypes result from a combination of cell autonomous and non-autonomous requirements for Cdk4 function. One non-autonomous consequence of Cdk4-dependent deficient enterocyte growth is high expression of Delta in ISCs and Delta retention in enteroblasts. We postulate that aberrant activation of the Delta–Notch pathway is a possible partial cause of lost ISC stemness. These results support the idea that enterocytes contribute to a putative stem cell niche that maintains intestinal homeostasis in the Drosophila anterior midgut. PMID:26879465

  8. Cdk4 functions in multiple cell types to control Drosophila intestinal stem cell proliferation and differentiation.

    PubMed

    Adlesic, Mojca; Frei, Christian; Frew, Ian J

    2016-01-01

    The proliferation of intestinal stem cells (ISCs) and differentiation of enteroblasts to form mature enteroendocrine cells and enterocytes in the Drosophila intestinal epithelium must be tightly regulated to maintain homeostasis. We show that genetic modulation of CyclinD/Cdk4 activity or mTOR-dependent signalling cell-autonomously regulates enterocyte growth, which influences ISC proliferation and enteroblast differentiation. Increased enterocyte growth results in higher numbers of ISCs and defective enterocyte growth reduces ISC abundance and proliferation in the midgut. Adult midguts deficient for Cdk4 show severe disruption of intestinal homeostasis characterised by decreased ISC self-renewal, enteroblast differentiation defects and low enteroendocrine cell and enterocyte numbers. The ISC/enteroblast phenotypes result from a combination of cell autonomous and non-autonomous requirements for Cdk4 function. One non-autonomous consequence of Cdk4-dependent deficient enterocyte growth is high expression of Delta in ISCs and Delta retention in enteroblasts. We postulate that aberrant activation of the Delta-Notch pathway is a possible partial cause of lost ISC stemness. These results support the idea that enterocytes contribute to a putative stem cell niche that maintains intestinal homeostasis in the Drosophila anterior midgut. PMID:26879465

  9. Upregulation of KPNβ1 in gastric cancer cell promotes tumor cell proliferation and predicts poor prognosis.

    PubMed

    Zhu, Jia; Wang, Yingying; Huang, Hua; Yang, Qichang; Cai, Jing; Wang, Qiuhong; Gu, Xiaoling; Xu, Pan; Zhang, Shusen; Li, Manhua; Ding, Haifang; Yang, Lei

    2016-01-01

    KPNβ1, also known as importin β, P97, is reported as one of soluble transport factors that mediates transportion of proteins and RNAs between the nucleus and cytoplasm in cellular process. Recent studies show that KPNβ1 is a tumor gene which is highly expressed in several malignant tumors such as ovarian cancer, cervical tumor, neck cancer, and lung cancer via promoting cell proliferation or inhibiting cell apoptotic pathways. However, the the role of KPNβ1 in gastric cancer remains unclear. In this study, Western blot and immunohistochemistrical analyses showed that KPNβ1 was significantly upregulated in clinical gastric cancer specimens compared with adjacent noncancerous tissues. KPNβ1 was positively correlated with tumor grade, Ki-67, and predicted poor prognosis of gastric cancer. More importantly, through starvation-refeeding model, CCK8 assay, flow cytometry, colony formation assays, the vitro studies demonstrated that KPNβ1 promoted proliferation of gastric cancer cells, while KPNβ1 knockdown led to decreased cell proliferation and arrested cell cycle at G1 phase. Furthermore, our results also indicated that KPNβ1 expression could result in docetaxel resistance. And, KPNβ1 could interact with Stat1, contributed to its nucleus import in gastric cancer cells. These findings provided a novel promising therapeutic targets for clinical treatment against human gastric cancer. PMID:26242264

  10. T-cell abnormalities in common variable immunodeficiency: the hidden defect

    PubMed Central

    Wong, Gabriel K; Huissoon, Aarnoud P

    2016-01-01

    This review discusses how the T-cell compartment in common variable immunodeficiency is marked by the premature arrest in thymic output, leading to T-cell exhaustion and immune dysregulation. Although B cells have been the main focus of the disorder, ample experimental data suggest that T-cell abnormalities can be seen in a large proportion of Freiburg Group 1a patients and those suffering from inflammatory complications. The reductions in T-cell receptor excision circles, naïve T cells, invariant NKT cells and regulatory T cells suggest a diminished thymic output, while CD8 T cells are driven towards exhaustion either via an antigen-dependent or an antigen-independent manner. The theoretical risk of anti-T-cell therapies is discussed, highlighting the need for an international effort in generating longitudinal data in addition to better-defined underlying molecular characterisation. PMID:27153873

  11. Molecular analysis of the effect of short-chain fatty acids on intestinal cell proliferation.

    PubMed

    Blottière, Hervé M; Buecher, Bruno; Galmiche, Jean-Paul; Cherbut, Christine

    2003-02-01

    Short-chain fatty acids (SCFA), particularly butyrate, were shown to regulate cell proliferation in vitro and in vivo. Indeed, butyrate is the major fuel for colonic epithelial cells, and it can influence cell proliferation through the release of growth factors or gastrointestinal peptides such as gastrin, or through modulation of mucosal blood flow. Lastly, SCFA can act directly on genes regulating cell proliferation, and butyrate is the main SCFA to display such an effect. Butyrate inhibits histone deacetylase, which will allow histone hyperacetylation. Such hyperacetylation leads to transcription of several genes, including p21/Cip1. Moreover, it will allow cyclin D3 hyper-expression by inhibiting its degradation. The induction of the cyclin-dependent kinase inhibitory protein p21/Cip1 accounts for cell arrest in the G1 phase of the cell cycle. However, in the absence of p21 other mechanisms are initiated, leading to inhibition of cell proliferation. PMID:12740064

  12. Interaction of osteoblast-like cells with serum and fibronectin: effects on cell motility and proliferation in vitro

    SciTech Connect

    Zuk, A.

    1986-01-01

    Osteoblast migration and proliferation are believed to occur during bone remodelling, in particular after osteoclastic bone resorption and prior to osteoblastic bone formation. In order to study migration and proliferation in vitro, the model of Alessandri et al. (1983) was modified. The model entailed seeding osteoblast-like cells into wells cut in agar and quantifying migration and proliferation peripheral to the well. Cell morphology also was described. The data indicated that on growth surfaces enriched with varying concentrations of fetal calf serum (FSC), the quantification of migration and proliferation was related both to percent cell attachment and to FCS-concentration. Because few osteoblast-like cells incorporated (/sup 3/H-TdR), it was concluded that the appearance of cells peripheral to the well was due to migration, and not to proliferation. Cell morphology and myosin distribution and organization indicated that osteoblast-like cells at the periphery of the cell culture (i.e. leading edge) may have been directionally migrating whereas cells behind the leading edge may have been engaged in non-directional migration. The migration, proliferation, and morphology of osteoblast-like cells cultured on fibronectin (FN) enriched growth surfaces also was examined. The quantification of migration and proliferation was related to the FN-concentration applied to the growth surface. Because few osteoblast-like cells incorporated /sup 3/H-TdR and cell morphology indicated migration, it was concluded that osteoblast-like cells on FN-enriched growth surfaces are specialized, in part, for migration.

  13. Differential effects of somatostatin and angiopeptin on cell proliferation

    PubMed Central

    Alderton, Forbes; Lauder, Heather; Feniuk, Wasyl; Fan, Tai-Ping D; Humphrey, Patrick P A

    1998-01-01

    Somatostatin (SRIF) exerts antiproliferative effects, and angiopeptin (an sst2/sst5 receptor-selective analogue) has recently been evaluated in clinical trials for the prophylaxis of restenosis following coronary angioplasty. Using an in vitro model of cell growth we have examined the effects of SRIF and angiopeptin on cell proliferation in CHO-K1 cells stably transfected with the human or rat recombinant sst2 or sst5 receptor and compared these with their effects on rat aortic vascular smooth muscle cells (VSMC) expressing endogenous somatostatin receptors.In CHO-K1 cells, expressing either human or rat recombinant sst2 or sst5 receptors, or in rat aortic VSMC, SRIF and angiopeptin (0.1–1000 nM) had no effect on basal re-growth of cells into a denuded area of a previously confluent monolayer. In contrast, basic fibroblast growth factor (bFGF, 10 ng ml−1) stimulated re-growth of these cells.SRIF (0.1–1000 nM) caused a concentration-dependent inhibition of the bFGF-stimulated re-growth in CHO-K1 cells expressing human sst2 (h sst2) or sst5 (h sst5) receptors (pIC50=8.05±0.03 and 8.56±0.12, respectively). In contrast, angiopeptin (0.1–1000 nM) acted as a partial agonist at the h sst2 receptor (44.6±2.7% inhibition of the bFGF-stimulated re-growth at 100 nM; pIC50=8.69±0.25) but was devoid of any agonist activity at the h sst5 receptor.In CHO-K1 cells stably expressing rat recombinant sst2 (r sst2) or sst5 (r sst5) receptors, SRIF (0.1–1000 nM) was able to inhibit the bFGF-stimulated re-growth (pIC50=7.98±24 and 8.50±0.12, respectively). Angiopeptin (0.1–1000 nM) caused a concentration-dependent inhibition of bFGF-stimulated re-growth at the r sst2 receptor (pIC50=8.08±0.24) but acted as a partial agonist at the r sst5 receptor (maximum response=57.7±3.6% inhibition of bFGF-stimulated re-growth at 100 nM; pIC50=8.60±0.16).Although angiopeptin was inactive as an agonist at the h sst5 receptor, 100

  14. Effect of advanced glycation end-products on cell proliferation and cell death.

    PubMed

    Peterszegi, G; Molinari, J; Ravelojaona, V; Robert, L

    2006-09-01

    The effect of advanced glycation end products (AGE-s) was studied on the proliferation and cell death of human skin fibroblasts in culture. Several AGE-products were prepared from proteins, a peptide and amino acids, using Glucose or Fructose, with or without Fe2+. The AGE preparations increased cell death at the 7th day, after only 72 hours of incubation. Some of these glycation products modified also proliferation. This effect of AGE-s was even maintained without these products in fresh medium for a second period of incubation up to 10 days from the start of the experiment. In order to explore the role of AGE-receptors, especially of AGE-receptor and of growth factor receptors (fibroblast and epidermal growth factors receptors), antibodies to these receptors were added to cell cultures and their effect on both cell death and proliferation were determined as for the AGE-s. These anti-receptor antibodies imitated to some extent the results obtained with AGE-s, producing increase of cell death and proliferation, followed above a certain concentration of antibodies by a decrease and a new increase or plateau. This might correspond to the internalization of the receptors followed by a re-expression on the cell membrane. The role of receptor-mediated Reactive Oxygen Species-production was also explored using scavengers: N-acetyl-cysteine (NAC), L-Carnosine, superoxide dismutase (SOD) and Catalase. Several of these scavengers decreased cell death, suggesting that Reactive Oxygen Species-production is partially involved in the observed phenomena. PMID:16919894

  15. Induction of cell proliferation, clonogenicity and cell accumulation in S phase as a consequence of human UBE2Q1 overexpression

    PubMed Central

    Fahmidehkar, Mohammad Ali; Shafiee, Sayed Mohammad; Eftekhar, Ebrahim; Mahbudi, Laleh; Seghatoleslam, Atefeh

    2016-01-01

    Ubiquitination is an important cellular mechanism with a pivotal role in the degradation of abnormal or short-lived proteins and the regulation of cell cycle and cell growth. The ubiquitin-proteasome pathway is altered in multiple types of human malignancies, including colorectal cancer (CRC). The alteration in the expression of the novel human gene ubiquitin-conjugating enzyme E2 Q1 (UBE2Q1), as a putative member of the E2 ubiquitin-conjugating enzyme family, has been reported in several malignancies, including carcinoma of the breast, hepatocellular and colorectal cancer, and pediatric acute lymphoblastic leukemia. In the present study, the effect of UBE2Q1 overexpression on cell growth, clonogenicity, motility and cell cycle was investigated in a CRC cell line. The UBE2Q1 gene was cloned in the pCMV6-AN-GFP expression vector. A series of stable transfectants of SW1116 cells overexpressing UBE2Q1 protein were established and confirmed by fluorescence microscopy and western blotting. Using these cells, MTT assay was performed to evaluate cell growth and proliferation, while crystal violet staining was used for clonogenicity assay. Cell cycle analysis was also performed to survey the ratio of cells accumulated in different phases of the cell cycle upon transfection. The motility of these cells was also studied using wound healing assay. UBE2Q1 transfectants exhibited a faster growth in cell culture, increased colony formation capacity and enhanced motility compared with control non-transfected cells and cells transfected with empty vector (mock-transfected cells). UBE2Q1 overexpression also resulted in a significant decrease in the number of cells accumulated in the G0/G1 phase of the cell cycle. The present findings suggest that UBE2Q1 may function as an oncogene that induces proliferation of cancer cells, and could be a novel diagnostic tool and a potential therapeutic target for CRC. PMID:27602158

  16. Suppression of lymphocyte proliferation by marijuana components is related to cell number and cell source

    SciTech Connect

    Klein, T.; Pross, S.; Newton, C.; Friedman, H.

    1986-03-05

    Conflicting reports have appeared concerning the effect of marijuana components on immune responsiveness. The authors have observed that the effect of cannabinoids on lymphocyte proliferation varied with both the concentration of the drug and the mitogen used. They now report that at a constant concentration of drug, the cannabinoid effect varied from no effect to suppression depending upon the number of cells in culture and the organ source of the cells. Dispersed cell suspensions of mouse lymph node, spleen, and thymus were prepared and cultured at varying cell numbers with either delta-9-tetrahydrocannabinol or 11-hydroxy-delta-9-tetrahydrocannabinol and various mitogens. Lymphocyte proliferation was analyzed by /sup 3/H-thymidine incorporation. T-lymphocyte mitogen responses in cultures containing high cell numbers were unaffected by the cannabinoids but as cell numbers were reduced a suppression of the response was observed. Furthermore, thymus cells were considerably more susceptible to cannabinoid suppression than cells from either lymph node or spleen. These results suggest that certain lymphocyte subpopulations are more sensitive to cannabinoid suppression and that in addition to drug concentration other variables such as cell number and cell source must be considered when analyzing cannabinoid effects.

  17. Gallic acid suppresses cell viability, proliferation, invasion and angiogenesis in human glioma cells

    PubMed Central

    Lu, Yong; Jiang, Feng; Jiang, Hao; Wu, Kalina; Zheng, Xuguang; Cai, Yizhong; Katakowski, Mark; Chopp, Michael; To, Shing-Shun Tony

    2010-01-01

    Gallic acid, an organic acid, also known as 3,4,5-trihydroxybenzoic acid, is cytotoxic against certain cancer cells, without harming normal cells. The objective of this study is to evaluate whether gallic acid can inhibit glioma cell viability, proliferation, invasion and reduce glioma cell mediated angiogenesis. Treatment of U87 and U251n glioma cells with gallic acid inhibited cell viability in a dose- and time-dependent manner. BrdU and tube formation assays indicated that gallic acid significantly decreased glioma cell proliferation and tube formation in mouse brain endothelial cells, respectively. In addition, gallic acid decreased U87 cell invasion in vitro. Western blot analysis showed that expression of ADAM17, p-Akt and p-Erk was suppressed by gallic acid in both U87 and U251n cell lines. These data suggest that suppression of ADAM17 and downregulation of PI3K/Akt and Ras/MAPK signaling pathways may contribute to gallic acid-induced decrease of invasiveness. Gallic acid may be a valuable candidate for treatment of brain tumor. PMID:20553913

  18. The Analysis of Cell Cycle, Proliferation, and Asymmetric Cell Division by Imaging Flow Cytometry.

    PubMed

    Filby, Andrew; Day, William; Purewal, Sukhveer; Martinez-Martin, Nuria

    2016-01-01

    Measuring cellular DNA content by conventional flow cytometry (CFC) and fluorescent DNA-binding dyes is a highly robust method for analysing cell cycle distributions within heterogeneous populations. However, any conclusions drawn from single-parameter DNA analysis alone can often be confounded by the asynchronous nature of cell proliferation. We have shown that by combining fluorescent DNA stains with proliferation tracking dyes and antigenic staining for mitotic cells one can elucidate the division history and cell cycle position of any cell within an asynchronously dividing population. Furthermore if one applies this panel to an imaging flow cytometry (IFC) system then the spatial information allows resolution of the four main mitotic phases and the ability to study molecular distributions within these populations. We have employed such an approach to study the prevalence of asymmetric cell division (ACD) within activated immune cells by measuring the distribution of key fate determining molecules across the plane of cytokinesis in a high-throughput, objective, and internally controlled manner. Moreover the ability to perform high-resolution, temporal dissection of the cell division process lends itself perfectly to investigating the influence chemotherapeutic agents exert on the proliferative capacity of transformed cell lines. Here we describe the method in detail and its application to both ACD and general cell cycle analysis. PMID:27460238

  19. Gastrodin inhibits cell proliferation in vascular smooth muscle cells and attenuates neointima formation in vivo

    PubMed Central

    ZHU, LIHUA; GUAN, HONGJING; CUI, CHANGPING; TIAN, SONG; YANG, DA; WANG, XINAN; ZHANG, SHUMING; WANG, LANG; JIANG, HONG

    2012-01-01

    Vascular smooth muscle cell (VSMC) proliferation plays a critical role in the development of vascular diseases. In the present study, we tested the efficacy and the mechanisms of action of gastrodin, a bioactive component of the Chinese herb Gastrodia elata Bl, in relation to platelet-derived growth factor-BB (PDGF-BB)-dependent cell proliferation and neointima formation after acute vascular injury. Cell experiments were performed with VSMCs isolated from rat aortas. WST and BrdU incorporation assays were used to evaluate VSMC proliferation. Eight-week-old C57BL/6 mice were used for the animal experiments. Gastrodin (150 mg/kg/day) was administered in the animal chow for 14 days, and the mice were subjected to wire injury of the left carotid artery. Our data demonstrated that gastrodin attenuated the VSMC proliferation induced by PDGF-BB, as assessed by WST assay and BrdU incorporation. Gastrodin influenced the S-phase entry of VSMCs and stabilised p27Kip1 expression. In addition, pre-incubation with sinomenine prior to PDGF-BB stimulation led to increased smooth muscle-specific gene expression, thereby inhibiting VSMC dedifferentiation. Gastrodin treatment also reduced the intimal area and the number of PCNA-positive cells. Furthermore, PDGF-BB-induced phosphorylation of ERK1/2, p38 MAPK, Akt and GSK3β was suppressed by gastrodin. Our results suggest that gastrodin can inhibit VSMC proliferation and attenuate neointimal hyperplasia in response to vascular injury. Furthermore, the ERK1/2, p38 MAPK and Akt/GSK3β signalling pathways were found to be involved in the effects of gastrodin. PMID:22922870

  20. Cell proliferation in the gastric corpus in Helicobacter pylori associated gastritis and after gastric resection.

    PubMed Central

    Lynch, D A; Mapstone, N P; Clarke, A M; Jackson, P; Dixon, M F; Quirke, P; Axon, A T

    1995-01-01

    Patients who have undergone gastric resection are at higher risk of developing gastric carcinoma than normal subjects, and bile reflux is believed to play a role in carcinogenesis. 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. Helicobacter pylori is considered a major risk factor for gastric cancer in the intact stomach. It has been shown previously that antral cell proliferation is increased in H pylori gastritis and falls to normal levels after eradication of the organism. Little is known of corpus cell proliferation in H pylori gastritis or after gastric resection. Using in vitro bromodeoxyuridine labelling of endoscopic biopsy specimens we have found that corpus cell proliferation is increased in H pylori gastritis. Cell proliferation was greater in corpus biopsy specimens of resected stomachs than in H pylori gastritis. Subgroup analysis of patients who had undergone gastric resection indicated that those positive for H pylori had higher levels of cell proliferation than those negative for the organism. These findings provide further evidence that H pylori and bile have a role in gastric carcinogenesis and suggest that their presence has a synergistic effect on gastric epithelial cell proliferation. Images Figure 1 Figure 2 PMID:7698691

  1. Mixtures of four organochlorines enhance human breast cancer cell proliferation.

    PubMed Central

    Payne, J; Scholze, M; Kortenkamp, A

    2001-01-01

    In view of the large differences between the concentrations of estrogenic chemicals needed to elicit effects in in vitro assays and their levels in human tissues, it is hard to explain possible health risks in terms of exposure to individual compounds. Human populations, however, are exposed to mixtures of estrogenic and estrogen-like agents and it is necessary to consider the impact of combined effects. We assessed the combined effects of 1-(o-chlorophenyl)-1-(p-chlorophenyl)-2,2,2-trichloroethane (o,p'-DDT), 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), beta-hexachlorocyclohexane (beta-HCH), and 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (p,p'-DDT) on the induction of cell proliferation in MCF-7 cells. All four compounds are persistent organochlorines that can be found in human tissues. We performed extensive concentration-response analyses with the single agents to predict the effects of two mixtures of all four compounds with different mixture ratios. We calculated the predictions by using the pharmacologically well-founded models of concentration addition and independent action and then tested them experimentally. o,p'-DDT, p,p'-DDE, beta-HCH, and p,p'-DDT acted together to produce proliferative effects in MCF-7 cells. The combined effect of the four agents could be predicted on the basis of data about single agent concentration-response relationships. Regression analysis demonstrated that there were combination effects even when each mixture component was present at levels at or below its individual no-observed-effect-concentration. We assessed combination effects in two ways: First, evaluations in relation to the proliferative responses induced by single mixture components revealed that the combination effects were stronger than the effects of the most potent constituent. Thus, according to this method of evaluation, the combined effects may be termed synergistic. Second, comparisons with the expected effects, as predicted by concentration

  2. Sox2 Activates Cell Proliferation and Differentiation in the Respiratory Epithelium

    PubMed Central

    Tompkins, David H.; Besnard, Valérie; Lange, Alexander W.; Keiser, Angela R.; Wert, Susan E.; Bruno, Michael D.; Whitsett, Jeffrey A.

    2011-01-01

    Sox2, a transcription factor critical for the maintenance of embryonic stem cells and induction of pluripotent stem cells, is expressed exclusively in the conducting airway epithelium of the lung, where it is required for differentiation of nonciliated, goblet, and ciliated cells. To determine the role of Sox2 in respiratory epithelial cells, Sox2 was selectively and conditionally expressed in nonciliated airway epithelial cells and in alveolar type II cells in the adult mouse. Sox2 induced epithelial cell proliferation within 3 days of expression. Epithelial cell proliferation was associated with increased Ki-67 and cyclin D1 staining. Expression of cell cycle genes, including FoxM1, Ccna2 (Cyclin A2), Ccnb2 (Cyclin B2), and Ccnd1 (Cyclin D1), was increased. Consistent with a role in cell proliferation, Sox2 activated the transcription of FoxM1 in vitro. In alveoli, Sox2 caused hyperplasia and ectopic differentiation of epithelial cells to those with morphologic and molecular characteristics of conducting airway epithelium. Sox2 induced the expression of conducting airway epithelial specific genes, including Scgb1a1, Foxj1, Tubb3, and Cyp2f2. Although prolonged expression of Sox2 caused cell proliferation and epithelial hyperplasia, Sox2 did not induce pulmonary tumors. Sox2 induces proliferation of respiratory epithelial cells and, subsequently, partially reprograms alveolar epithelial cells into cells with characteristics of the conducting airways. PMID:20855650

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

    SciTech Connect

    Kawai, Ikuma; Hisaki, Tomoka; Sugiura, Koji; Naito, Kunihiko; Kano, Kiyoshi

    2012-10-26

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

  4. Use of the lectin from Amaranthus caudatus as a histochemical probe of proliferating colonic epithelial cells.

    PubMed

    Boland, C R; Chen, Y F; Rinderle, S J; Resau, J H; Luk, G D; Lynch, H T; Goldstein, I J

    1991-01-15

    A newly isolated lectin, Amaranthus caudatus agglutinin (also called amaranthin or ACA), which binds to the Thomsen-Friedenreich antigen (T-antigen) and its sialylated variants, was used as a histochemical probe for proliferating cells in sections of human colonic tissues. Binding inhibition studies revealed that ACA binds to different sites on histological sections when compared to peanut agglutinin, which also recognizes the T-antigen. ACA bound selectively to the cells at the base of the colonic crypt [46 +/- 4% (SEM) of glands] which is the zone of proliferation in this tissue and preferentially labeled cytoplasmic and apical membrane glycoconjugates. Only 7 +/- 2% of the upper portions of the colonic crypts were labeled (P less than 0.001 compared to the base), and this was largely a result of extensive labeling in 2 of 23 samples studies. A marked increase in histochemical labeling by ACA was seen in adenomatous polyps and adenocarcinomas of the colon, in which 82 +/- 7 and 97 +/- 2% of the glandular units were labeled, respectively. Transitional mucosa and connective tissue adjacent to cancers were also labeled by ACA. Neuraminidase studies indicated that removal of sialic acid residues enhanced binding by peanut agglutinin, but not ACA, to glycoconjugates in cancer specimens. Specimens of colonic tissue from patients with familial adenomatous polyposis (FAP) were examined with ACA; 83 +/- 7% of adenomatous glands and 60 +/- 7% of glands in flat, normal-appearing tissue were labeled. Colonic tissues from persons at 50% risk for hereditary nonpolyposis colorectal cancer (HNPCC), FAP, and normal colons were studied and given "weighted average" labelling scores that ranged from 0-400 to accommodate variable intensity and distribution of labeling. Normal colons had a weighted average score of 65 +/- 33; FAP tissues had a score of 224 +/- 76 (P less than 0.001 compared to normal colon) and HNPCC tissues had a score of 74 +/- 70 (P less than 0.05 compared to

  5. Okadaic Acid Toxin at Sublethal Dose Produced Cell Proliferation in Gastric and Colon Epithelial Cell Lines

    PubMed Central

    del Campo, Miguel; Toledo, Héctor; Lagos, Néstor

    2013-01-01

    The aim of this study was to analyze the effect of Okadaic Acid (OA) on the proliferation of gastric and colon epithelial cells, the main target tissues of the toxin. We hypothesized that OA, at sublethal doses, activates multiple signaling pathways, such as Erk and Akt, through the inhibition of PP2A. To demonstrate this, we carried out curves of doses and time response against OA in AGS, MKN-45 and Caco 2 cell lines, and found an increase in the cell proliferation at sublethal doses, at 24 h or 48 h exposure. Indeed, cells can withstand high concentrations of the toxin at 4 h exposure, the time chosen considering the maximum time before total gastric emptying. We have proved that this increased proliferation is due to an overexpression of Cyclin B, a cyclin that promotes the passage from G2 to mitosis. In addition, we have demonstrated that OA induces activation of Akt and Erk in the three cells lines, showing that OA can activate pathways involved in oncogenesis. In conclusion, this study contributes to the knowledge about the possible effects of chronic OA consumption. PMID:24317467

  6. Kuwanon V Inhibits Proliferation, Promotes Cell Survival and Increases Neurogenesis of Neural Stem Cells

    PubMed Central

    Kong, Sun-Young; Park, Min-Hye; Lee, Mina; Kim, Jae-Ouk; Lee, Ha-Rim; Han, Byung Woo; Svendsen, Clive N.; Sung, Sang Hyun; Kim, Hyun-Jung

    2015-01-01

    Neural stem cells (NSCs) have the ability to proliferate and differentiate into neurons and glia. Regulation of NSC fate by small molecules is important for the generation of a certain type of cell. The identification of small molecules that can induce new neurons from NSCs could facilitate regenerative medicine and drug development for neurodegenerative diseases. In this study, we screened natural compounds to identify molecules that are effective on NSC cell fate determination. We found that Kuwanon V (KWV), which was isolated from the mulberry tree (Morus bombycis) root, increased neurogenesis in rat NSCs. In addition, during NSC differentiation, KWV increased cell survival and inhibited cell proliferation as shown by 5-bromo-2-deoxyuridine pulse experiments, Ki67 immunostaining and neurosphere forming assays. Interestingly, KWV enhanced neuronal differentiation and decreased NSC proliferation even in the presence of mitogens such as epidermal growth factor and fibroblast growth factor 2. KWV treatment of NSCs reduced the phosphorylation of extracellular signal-regulated kinase 1/2, increased mRNA expression levels of the cyclin-dependent kinase inhibitor p21, down-regulated Notch/Hairy expression levels and up-regulated microRNA miR-9, miR-29a and miR-181a. Taken together, our data suggest that KWV modulates NSC fate to induce neurogenesis, and it may be considered as a new drug candidate that can regenerate or protect neurons in neurodegenerative diseases. PMID:25706719

  7. CCDC34 is up-regulated in bladder cancer and regulates bladder cancer cell proliferation, apoptosis and migration

    PubMed Central

    Gong, Yanqing; Qiu, Wei; Ning, Xianghui; Yang, Xinyu; Liu, Libo; Wang, Zicheng; Lin, Jian; Li, Xuesong; Guo, Yinglu

    2015-01-01

    The coiled coil is a superhelical structural protein motif involved in a diverse array of biological functions, and the abnormal expression of the coiled-coil domain containing proteins has a direct link with the phenotype of tumor cell migration, invasion and metastasis. The aim of this study was to investigate the critical role of Coiled-coil domain-containing protein 34 (CCDC34) in bladder carcinogenesis, which has never been reported to date. Here, we found CCDC34 expression was elevated in bladder cancer tissues and cell lines. The knockdown of CCDC34 via lentivirus-mediated siRNA significantly suppressed bladder cancer cells proliferation and migration, and induced cell cycle arrest at G2/M phase and increased apoptosis in vitro. In addition, CCDC34 knockdown suppressed bladder tumor growth in nude mice. Moreover, CCDC34 silencing decreased the phosphorylation of MEK, ERK1/2, JNK, p38 and Akt, and the expressions of c-Raf and c-Jun, indicating MAPK and AKT pathways (ERK/MAPK, p38/MAPK, JNK/MAPK and PI3K/Akt) might be involved in CCDC34 regulation of bladder cancer cell proliferation and migration. Our findings revealed for the first time a potential oncogenic role for CCDC34 in bladder carcinoma pathogenesis and it may serve as a biomarker or even a therapeutic target for bladder cancer. PMID:26312564

  8. Homotypic RANK signaling differentially regulates proliferation, motility and cell survival in osteosarcoma and mammary epithelial cells.

    PubMed

    Beristain, Alexander G; Narala, Swami R; Di Grappa, Marco A; Khokha, Rama

    2012-02-15

    RANKL (receptor activator of NF-κB ligand) is a crucial cytokine for regulating diverse biological systems such as innate immunity, bone homeostasis and mammary gland differentiation, operating through activation of its cognate receptor RANK. In these normal physiological processes, RANKL signals through paracrine and/or heterotypic mechanisms where its expression and function is tightly controlled. Numerous pathologies involve RANKL deregulation, such as bone loss, inflammatory diseases and cancer, and aberrant RANK expression has been reported in bone cancer. Here, we investigated the significance of RANK in tumor cells with a particular emphasis on homotypic signaling. We selected RANK-positive mouse osteosarcoma and RANK-negative preosteoblastic MC3T3-E1 cells and subjected them to loss- and gain-of-RANK function analyses. By examining a spectrum of tumorigenic properties, we demonstrate that RANK homotypic signaling has a negligible effect on cell proliferation, but promotes cell motility and anchorage-independent growth of osteosarcoma cells and preosteoblasts. By contrast, establishment of RANK signaling in non-tumorigenic mammary epithelial NMuMG cells promotes their proliferation and anchorage-independent growth, but not motility. Furthermore, RANK activation initiates multiple signaling pathways beyond its canonical target, NF-κB. Among these, biochemical inhibition reveals that Erk1/2 is dominant and crucial for the promotion of anchorage-independent survival and invasion of osteoblastic cells, as well as the proliferation of mammary epithelial cells. Thus, RANK signaling functionally contributes to key tumorigenic properties through a cell-autonomous homotypic mechanism. These data also identify the likely inherent differences between epithelial and mesenchymal cell responsiveness to RANK activation. PMID:22421365

  9. Mesenchymal precursor cells maintain the differentiation and proliferation potentials of breast epithelial cells

    PubMed Central

    2014-01-01

    Introduction Stromal-epithelial interactions play a fundamental role in tissue homeostasis, controlling cell proliferation and differentiation. Not surprisingly, aberrant stromal-epithelial interactions contribute to malignancies. Studies of the cellular and molecular mechanisms underlying these interactions require ex vivo experimental model systems that recapitulate the complexity of human tissue without compromising the differentiation and proliferation potentials of human primary cells. Methods We isolated and characterized human breast epithelial and mesenchymal precursors from reduction mammoplasty tissue and tagged them with lentiviral vectors. We assembled heterotypic co-cultures and compared mesenchymal and epithelial cells to cells in corresponding monocultures by analyzing growth, differentiation potentials, and gene expression profiles. Results We show that heterotypic culture of non-immortalized human primary breast epithelial and mesenchymal precursors maintains their proliferation and differentiation potentials and constrains their growth. We further describe the gene expression profiles of stromal and epithelial cells in co-cultures and monocultures and show increased expression of the tumor growth factor beta (TGFβ) family member inhibin beta A (INHBA) in mesenchymal cells grown as co-cultures compared with monocultures. Notably, overexpression of INHBA in mesenchymal cells increases colony formation potential of epithelial cells, suggesting that it contributes to the dynamic reciprocity between breast mesenchymal and epithelial cells. Conclusions The described heterotypic co-culture system will prove useful for further characterization of the molecular mechanisms mediating interactions between human normal or neoplastic breast epithelial cells and the stroma, and will provide a framework to test the relevance of the ever-increasing number of oncogenomic alterations identified in human breast cancer. PMID:24916766

  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. PMID:26506049

  11. Testicular Sertoli cells influence the proliferation and immunogenicity of co-cultured endothelial cells

    SciTech Connect

    Fan, Ping; He, Lan; Pu, Dan; Lv, Xiaohong; Zhou, Wenxu; Sun, Yining; Hu, Nan

    2011-01-21

    Research highlights: {yields} The proliferation of dramatic increased by co-cultured with Sertoli cells. {yields} VEGF receptor-2 expression of ECs was up-regulated by co-cultured with Sertoli cells. {yields} The MHC expression of ECs induced by INF-{gamma} and IL-6, IL-8 and sICAM induced by TNF-{alpha} decreased respectively after co-cultured with Sertoli cells. {yields} ECs co-cultured with Sertoli cells also didn't increase the stimulation index of spleen lymphocytes. -- Abstract: The major problem of the application of endothelial cells (ECs) in transplantation is the lack of proliferation and their immunogenicity. In this study, we co-cultured ECs with Sertoli cells to monitor whether Sertoli cells can influence the proliferation and immunogenicity of co-cultured ECs. Sertoli cells were isolated from adult testicular tissue. ECs were divided into the control group and the experimental group, which included three sub-groups co-cultured with 1 x 10{sup 3}, 1 x 10{sup 4} or 1 x 10{sup 5} cell/ml of Sertoli cells. The growth and proliferation of ECs were observed microscopically, and the expression of vascular endothelial growth factor (VEGF) receptor-2 (KDR) was examined by Western blotting. In another experiment, ECs were divided into the control group, the single culture group and the co-culture group with the optimal concentration of Sertoli cells. After INF-{gamma} and TNF-{alpha} were added to the culture medium, MHC II antigen expression was detected by immunofluorescence staining and western blotting; interleukin (IL)-6, IL-8 and soluble intercellular adhesion molecule (sICAM) were measured in the culture medium by ELISA. We demonstrated that 1 x 10{sup 4} cell/ml Sertoli cells promoted the proliferation of co-cultured ECs more dramatically than that in other groups (P < 0.05). Western blotting showed that 1 x 10{sup 4} cell/ml of the Sertoli cells was most effective in the up-regulation of KDR expression in the co-cultured ECs (P < 0.05). Sertoli cells

  12. Self-correction of chromosomal abnormalities in human preimplantation embryos and embryonic stem cells.

    PubMed

    Bazrgar, Masood; Gourabi, Hamid; Valojerdi, Mojtaba Rezazadeh; Yazdi, Poopak Eftekhari; Baharvand, Hossein

    2013-09-01

    Aneuploidy is commonly seen in human preimplantation embryos, most particularly at the cleavage stage because of genome activation by third cell division. Aneuploid embryos have been used for the derivation of normal embryonic stem cell (ESC) lines and developmental modeling. This review addresses aneuploidies in human preimplantation embryos and human ESCs and the potential of self-correction of these aberrations. Diploid-aneuploid mosaicism is the most frequent abnormality observed; hence, embryos selected by preimplantation genetic diagnosis at the cleavage or blastocyst stage could be partly abnormal. Differentiation is known as the barrier for eliminating mosaic embryos by death and/or decreased division of abnormal cells. However, some mosaicisms, such as copy number variations could be compatible with live birth. Several reasons have been proposed for self-correction of aneuploidies during later stages of development, including primary misdiagnosis, allocation of the aneuploidy in the trophectoderm, cell growth advantage of diploid cells in mosaic embryos, lagging of aneuploid cell division, extrusion or duplication of an aneuploid chromosome, and the abundance of DNA repair gene products. Although more studies are needed to understand the mechanisms of self-correction as a rare phenomenon, most likely, it is related to overcoming mosaicism. PMID:23557100

  13. Newly identified interfibrillar collagen crosslinking suppresses cell proliferation and remodelling.

    PubMed

    Marelli, Benedetto; Le Nihouannen, Damien; Hacking, S Adam; Tran, Simon; Li, Jingjing; Murshed, Monzur; Doillon, Charles J; Ghezzi, Chiara E; Zhang, Yu Ling; Nazhat, Showan N; Barralet, Jake E

    2015-06-01

    Copper is becoming recognised as a key cation in a variety of biological processes. Copper chelation has been studied as a potential anti-angiogenic strategy for arresting tumour growth. Conversely the delivery of copper ions and complexes in vivo can elicit a pro-angiogenic effect. Previously we unexpectedly found that copper-stimulated intraperitoneal angiogenesis was accompanied by collagen deposition. Here, in hard tissue, not only was healing accelerated by copper, but again enhanced deposition of collagen was detected at 2 weeks. Experiments with reconstituted collagen showed that addition of copper ions post-fibrillogenesis rendered plastically-compressed gels resistant to collagenases, enhanced their mechanical properties and increased the denaturation temperature of the protein. Unexpectedly, this apparently interfibrillar crosslinking was not affected by addition of glucose or ascorbic acid, which are required for crosslinking by advanced glycation end products (AGEs). Fibroblasts cultured on copper-crosslinked gels did not proliferate, whereas those cultured with an equivalent quantity of copper on either tissue culture plastic or collagen showed no effect compared with controls. Although non-proliferative, fibroblasts grown on copper-cross-linked collagen could migrate, remained metabolically active for at least 14 days and displayed a 6-fold increase in Mmps 1 and 3 mRNA expression compared with copper-free controls. The ability of copper ions to crosslink collagen fibrils during densification and independently of AGEs or Fenton type reactions is previously unreported. The effect on MMP susceptibility of collagen and the dramatic change in cell behaviour on this crosslinked ECM may contribute to shedding some light on unexplained phenomena as the apparent benefit of copper complexation in fibrotic disorders or the enhanced collagen deposition in response to localised copper delivery. PMID:25907046

  14. Gli1 Mediates Lung Cancer Cell Proliferation and Sonic Hedgehog-Dependent Mesenchymal Cell Activation

    PubMed Central

    Bermudez, Olga; Hennen, Elisabeth; Koch, Ina; Lindner, Michael; Eickelberg, Oliver

    2013-01-01

    Non-Small-Cell-Lung-Cancer (NSCLC) represents approximately 85% of all lung cancers and remains poorly understood. While signaling pathways operative during organ development, including Sonic Hedgehog (Shh) and associated Gli transcription factors (Gli1-3), have recently been found to be reactivated in NSCLC, their functional role remains unclear. Here, we hypothesized that Shh/Gli1-3 could mediate NSCLC autonomous proliferation and epithelial/stromal signaling in the tumoral tissue. In this context, we have investigated the activity of Shh/Gli1-3 signaling in NSCLC in both, cancer and stromal cells. We report here that inhibition of Shh signaling induces a significant decrease in the proliferation of NSCLC cells. This effect is mediated by Gli1 and Gli2, but not Gli3, through regulation of cyclin D1 and cyclin D2 expression. While exogenous Shh was unable to induce signaling in either A549 lung adenocarcinoma or H520 lung squamous carcinoma cells, both cells were found to secrete Shh ligand, which induced fibroblast proliferation, survival, migration, invasion, and collagen synthesis. Furthermore, Shh secreted by NSCLC mediates the production of proangiogenic and metastatic factors in lung fibroblasts. Our results thus provide evidence that Shh plays an important role in mediating epithelial/mesenchymal crosstalk in NSCLC. While autonomous Gli activity controls NSCLC proliferation, increased Shh expression by NSCLC is associated with fibroblast activation in tumor-associated stroma. Our study highlights the relevance of studying stromal-associated cells in the context of NSCLC regarding new prognosis and therapeutic options. PMID:23667589

  15. Gli1 mediates lung cancer cell proliferation and Sonic Hedgehog-dependent mesenchymal cell activation.

    PubMed

    Bermudez, Olga; Hennen, Elisabeth; Koch, Ina; Lindner, Michael; Eickelberg, Oliver

    2013-01-01

    Non-Small-Cell-Lung-Cancer (NSCLC) represents approximately 85% of all lung cancers and remains poorly understood. While signaling pathways operative during organ development, including Sonic Hedgehog (Shh) and associated Gli transcription factors (Gli1-3), have recently been found to be reactivated in NSCLC, their functional role remains unclear. Here, we hypothesized that Shh/Gli1-3 could mediate NSCLC autonomous proliferation and epithelial/stromal signaling in the tumoral tissue. In this context, we have investigated the activity of Shh/Gli1-3 signaling in NSCLC in both, cancer and stromal cells. We report here that inhibition of Shh signaling induces a significant decrease in the proliferation of NSCLC cells. This effect is mediated by Gli1 and Gli2, but not Gli3, through regulation of cyclin D1 and cyclin D2 expression. While exogenous Shh was unable to induce signaling in either A549 lung adenocarcinoma or H520 lung squamous carcinoma cells, both cells were found to secrete Shh ligand, which induced fibroblast proliferation, survival, migration, invasion, and collagen synthesis. Furthermore, Shh secreted by NSCLC mediates the production of proangiogenic and metastatic factors in lung fibroblasts. Our results thus provide evidence that Shh plays an important role in mediating epithelial/mesenchymal crosstalk in NSCLC. While autonomous Gli activity controls NSCLC proliferation, increased Shh expression by NSCLC is associated with fibroblast activation in tumor-associated stroma. Our study highlights the relevance of studying stromal-associated cells in the context of NSCLC regarding new prognosis and therapeutic options. PMID:23667589

  16. Electrocardiographic abnormalities and dyslipidaemic syndrome in children with sickle cell anaemia

    PubMed Central

    Adegoke, Samuel Ademola; Okeniyi, John Akintunde Oladotun; Akintunde, Adeseye Abiodun

    2016-01-01

    Summary Background Lipid and electrocardiographic (ECG) abnormalities have been reported in adults with sickle cell anaemia (SCA) and may reflect underlying structural and/ or functional damage. However, the relationship between ECG and lipid abnormalities among children with sickle cell disease is not fully understood. Objectives To compare the steady-state lipid and ECG abnormalities in children with SCA to the controls and examine the hypothesis that lipid abnormalities are closely related to electrocardiographic abnormalities, and therefore are a reflection of cardiac damage among these children. Methods: Clinical, laboratory and ECG profiles of 62 children with SCA and 40 age- and gender-matched haemoglobin AA controls were compared. The influence of clinical characteristics, lipids profiles, markers of haemolysis, and renal and hepatic dysfunction on ECG pattern in children with SCA was then determined. Results The patients had lower average diastolic and mean arterial blood pressure, total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels than the controls, (p = 0.001, 0.002, 0.000 and 0.000, respectively). The mean triglyceride level was significantly higher (p < 0.001), while high-density lipoprotein cholesterol (HDL-C) levels were comparable (p = 0.858). The cases were about six times more likely to have left ventricular hypertrophy than the controls (OR = 6.4, 95% CI = 2.7–15.6, p = 0.000). Haematocrit level had a negative correlation with QTC (r = –0.3, p = 0.016) and QT intervals (r = – 0.3, p = 0.044). Triglyceride levels had a positive correlation with the PR interval (r = 0.3, p = 0.012), while serum alanine transferase (ALT) concentrations had an inverse correlation with PR interval (r = –0.3, p = 0.015). There was no statistical difference in the sociodemographic and clinical characteristics of the SCA children with or without ECG abnormalities. However, the mean triglyceride and serum ALT levels in those with ECG

  17. Silencing Aurora-A with siRNA inhibits cell proliferation in human lung adenocarcinoma cells.

    PubMed

    Zhong, Ning; Shi, Shunbin; Wang, Hongzhen; Wu, Guangzhou; Wang, Yunliang; Ma, Qiang; Wang, Hongwei; Liu, Yuanhua; Wang, Jinzhi

    2016-09-01

    Aurora kinase A (AURKA) is an oncogenic serine/threonine kinase, it plays important roles in tumorigenesis and chemoresistance. In this study, we investigated the expression of AURKA in lung adenocarcinoma tissues, the role of small interference RNA targeting AURKA on growth, cell cycle, and apoptosis of lung adenocarcinoma cell lines in vitro. The AURKA is highly expressed in lung adenocarcinoma tissues and human lung adenocarcinoma cell lines. Lentivirus-mediated short hairpin RNA (shRNA) was used to knock down AURKA expression in human lung adenocarcinoma cell lines H1299 and A549. The results indicated that depletion of AURKA could inhibit cell growth, cause cell cycle arrest and apoptosis. The potential mechanisms of AURKA inhibition induced cell cycle arrest and apoptosis are associated with downregulated RAF-1, CCND2, CCND3, CDK4, PAK4, EGFR and upregulated WEE1 expression. Furthermore, AURKA knockdown cooperated with vincristine (VCR) to repress A549 cell proliferation. Therefore, AURKA plays important roles in the proliferation of human lung adenocarcinoma cells, which suggests that AURKA could be a promising tool for lung adenocarcinoma therapy. PMID:27571708

  18. Low dose perfluorooctanoate exposure promotes cell proliferation in a human non-tumor liver cell line.

    PubMed

    Zhang, Hongxia; Cui, Ruina; Guo, Xuejiang; Hu, Jiayue; Dai, Jiayin

    2016-08-01

    Perfluorooctanoate (PFOA) is a well-known persistent organic pollutant widely found in the environment, wildlife and humans. Medical surveillance and experimental studies have investigated the potential effects of PFOA on human livers, but the hepatotoxicity of PFOA on humans and its underlying mechanism remain to be clarified. We exposed a human liver cell line (HL-7702) to 50μM PFOA for 48h and 96h, and identified 111 significantly differentially expressed proteins by iTRAQ analysis. A total of 46 proteins were related to cell proliferation and apoptosis. Through further analysis of the cell cycle, apoptosis and their related proteins, we found that low doses of PFOA (50-100μM) promoted cell proliferation and numbers by promoting cells from the G1 to S phases, whereas high doses of PFOA (200-400μM) led to reduced HL-7702 cell numbers compared with that of the control mainly due to cell cycle arrest in the G0/G1 phase. To our knowledge, this is the first report on the promotion of cell cycle progression in human cells following PFOA exposure. PMID:27045622

  19. Dental pulp stem cells suppress the proliferation of lymphocytes via transforming growth factor-β1.

    PubMed

    Ding, Gang; Niu, Jianyi; Liu, Yi

    2015-04-01

    Dental pulp stem cells (DPSCs) possess self-renewal capability, multi-lineage differentiation potential, and can generate a dentin-pulp-like tissue in vivo, which is promising for tooth regeneration. To enlarge the cells resource of DPSCs and explore the feasibility of DPSCs-mediated immune therapy, it is prerequisite to investigate the immunological properties of DPSCs and the underlying mechanisms. Human DPSCs and peripheral blood mononuclear cells were isolated and cultured. Then we used lymphocytes proliferation assays, cytokines detection, Transwell cultures, neutralization experiments, and flow cytometry to examine the in vitro immune characteristics of DPSCs. We found that DPSCs failed to stimulate allogeneic T cells proliferation and suppressed T cells proliferation, B cells proliferation, and mixed lymphocyte reaction. In addition, DPSCs could up-regulate IL-10, down-regulate the production of IL-2, IL-17, and IFN-γ, and did not affect the production of IL-6. Monoclonal antibody against transforming growth factor-β1 restored the T cells proliferation inhibited by DPSCs. Moreover, the population of regulatory T cells increased significantly and T-helper 17 cells decreased significantly in peripheral blood mononuclear cells co-cultured with DPSCs. These data confirmed that DPSCs are low immunogenic, could inhibit the proliferation of lymphocytes, regulate the production of cytokines in vitro, and the secretion of transforming growth factor-β1 may be involved in this event. PMID:25605036

  20. Effect of molecular weight and concentration of hyaluronan on cell proliferation and osteogenic differentiation in vitro.

    PubMed

    Zhao, Ningbo; Wang, Xin; Qin, Lei; Guo, Zhengze; Li, Dehua

    2015-09-25

    Hyaluronan (HA), the simplest glycosaminoglycan and a major component of the extracellular matrix, exists in various tissues. It is involved in some critical biological procedures, including cellular signaling, cell adhesion and proliferation, and cell differentiation. The effect of molecular weight (MW) and concentration of HA on cell proliferation and differentiation was controversial. In this study, we investigated the effect of MW and concentration of HA on the proliferation and osteogenic differentiation of rabbit bone marrow-derived stem cells in vitro. Results showed that high MW HA decreased the cell adhesion rate in a concentration-dependant manner. The cell adhesion rate was decreased by increasing MW of HA. Cell proliferation was significantly enhanced by low MW HA (P < 0.05). The factorial analysis indicated that MW and concentration had an interactive effect on the cell adhesion rate and cell proliferation (P < 0.05). High MW HA increased the mRNA expressions of ALP, RUNX-2 and OCN. The higher the MW was, the higher the mRNA expressions were. The factorial analysis indicated that MW and concentration had an interactive effect on ALP mRNA expression (P < 0.05). HA of higher MW and higher concentration promoted bone formation. These findings provide some useful information in understanding the mechanism underlying the effect of MW and concentration of HA on cell proliferation and differentiation. PMID:26284973

  1. 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

  2. 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. PMID:26930190

  3. 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

  4. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    SciTech Connect

    Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing; Glaves, Richard Samuel Elliot; Ash, David E.; Mohanty, Dillip K.

    2014-07-18

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well.

  5. Dynamics of cell proliferation in the adult dentate gyrus of two inbred strains of mice

    NASA Technical Reports Server (NTRS)

    Hayes, N. L.; Nowakowski, R. S.

    2002-01-01

    The output potential of proliferating populations in either the developing or the adult nervous system is critically dependent on the length of the cell cycle (T(c)) and the size of the proliferating population. We developed a new approach for analyzing the cell cycle, the 'Saturate and Survive Method' (SSM), that also reveals the dynamic behaviors in the proliferative population and estimates of the size of the proliferating population. We used this method to analyze the proliferating population of the adult dentate gyrus in 60 day old mice of two inbred strains, C57BL/6J and BALB/cByJ. The results show that the number of cells labeled by exposure to BUdR changes dramatically with time as a function of the number of proliferating cells in the population, the length of the S-phase, cell division, the length of the cell cycle, dilution of the S-phase label, and cell death. The major difference between C57BL/6J and BALB/cByJ mice is the size of the proliferating population, which differs by a factor of two; the lengths of the cell cycle and the S-phase and the probability that a newly produced cell will die within the first 10 days do not differ in these two strains. This indicates that genetic regulation of the size of the proliferating population is independent of the genetic regulation of cell death among those newly produced cells. The dynamic changes in the number of labeled cells as revealed by the SSM protocol also indicate that neither single nor repeated daily injections of BUdR accurately measure 'proliferation.'.

  6. Ki-67 is required for maintenance of cancer stem cells but not cell proliferation

    PubMed Central

    Cidado, Justin; Wong, Hong Yuen; Rosen, D. Marc; Cimino-Mathews, Ashley; Garay, Joseph P.; Fessler, Abigail G.; Rasheed, Zeshaan A.; Hicks, Jessica; Cochran, Rory L.; Croessmann, Sarah; Zabransky, Daniel J.; Mohseni, Morassa; Beaver, Julia A.; Chu, David; Cravero, Karen; Christenson, Eric S.; Medford, Arielle; Mattox, Austin; De Marzo, Angelo M.; Argani, Pedram; Chawla, Ajay; Hurley, Paula J.; Lauring, Josh; Park, Ben Ho

    2016-01-01

    Ki-67 expression is correlated with cell proliferation and is a prognostic marker for various cancers; however, its function is unknown. Here we demonstrate that genetic disruption of Ki-67 in human epithelial breast and colon cancer cells depletes the cancer stem cell niche. Ki-67 null cells had a proliferative disadvantage compared to wildtype controls in colony formation assays and displayed increased sensitivity to various chemotherapies. Ki-67 null cancer cells showed decreased and delayed tumor formation in xenograft assays, which was associated with a reduction in cancer stem cell markers. Immunohistochemical analyses of human breast cancers revealed that Ki-67 expression is maintained at equivalent or greater levels in metastatic sites of disease compared to matched primary tumors, suggesting that maintenance of Ki-67 expression is associated with metastatic/clonogenic potential. These results elucidate Ki-67's role in maintaining the cancer stem cell niche, which has potential diagnostic and therapeutic implications for human malignancies. PMID:26823390

  7. Research on effect of minor bupleurum decoction of proliferation and apoptosis of esophageal cancer cell strain eca-109 cell.

    PubMed

    Li, Xiaofang; Sun, Miaomiao; Zhao, Zhihua; Yang, Jianping; Chen, Kuisheng

    2014-09-01

    The research protocol is MTT (Methyl Thiazolyl Tetrazolium) method, Hoechst33342 staining method and flow cytometry detection to observe the effect of minor bupleurum decoction on proliferation inhibition and apoptosis-inducing of esophageal cancer cell strain Eca-109 cell and its purpose is to discuss the effect. The result of MTT method shows that minor buplerum decoction can obviously inhibit proliferation of esophageal cancer cell strain Eca-109 cell. Apoptosis number of esophageal cancer cell increased with the increase of concentration of tetrandrine by the Hoechst 35528 staining experiment of cancer cell in three different concentrations. Flow cytometry detection result showed that cells in cell cycle G0/G1 of esophageal cancer cell strain Eca-109 cell increased obviously and cell in s period decreased significantly. This research proved that minor bupleurum decoction had anti-tumor effect and can influent proliferation and apoptosis of esophageal cancer cell strain Eca-109 cell. PMID:25262517

  8. Y-27632, a ROCK Inhibitor, Promoted Limbal Epithelial Cell Proliferation and Corneal Wound Healing

    PubMed Central

    Sun, Chi-Chin; Chiu, Hsiao-Ting; Lin, Yi-Fang; Lee, Kuo-Ying; Pang, Jong-Hwei Su

    2015-01-01

    Transplantation of ex vivo cultured limbal epithelial cells is proven effective in restoring limbal stem cell deficiency. The present study aimed to investigate the promoting effect of Y-27632 on limbal epithelial cell proliferation. Limbal explants isolated from human donor eyes were expanded three weeks on culture dishes and outgrowth of epithelial cells was subsequently subcultured for in vitro experiments. In the presence of Y-27632, the ex vivo limbal outgrowth was accelerated, particularly the cells with epithelial cell-like morphology. Y-27632 dose-dependently promoted the proliferation of in vitro cultured human limbal epithelial cells as examined by phase contrast microscopy and luminescent cell-viability assay 30 hours after the treatment. The colony forming efficacy determined 7 days after the treatment was enhanced by Y-27632 also in a dose-dependent manner. The number of p63- or Ki67-positive cells was dose-dependently increased in Y-27632-treated cultures as detected by immunofluorescent staining and western blotanalysis. Cell cycle analysis by flow cytometric method revealed an increase in S-phase proliferating cells. The epithelial woundclosure rate was shown to be faster in experimental group received topical treatment withY-27632 than the sham control using a rat corneal wounding model. These resultsdemonstrate that Y-27632 can promote both the ex vivo and in vitro proliferation oflimbal epithelial cell proliferation. The in vivo enhanced epithelial wound healingfurther implies that the Y-27632 may act as a new strategy for treating limbal stem cell deficiency. PMID:26673160

  9. Y-27632, a ROCK Inhibitor, Promoted Limbal Epithelial Cell Proliferation and Corneal Wound Healing.

    PubMed

    Sun, Chi-Chin; Chiu, Hsiao-Ting; Lin, Yi-Fang; Lee, Kuo-Ying; Pang, Jong-Hwei Su

    2015-01-01

    Transplantation of ex vivo cultured limbal epithelial cells is proven effective in restoring limbal stem cell deficiency. The present study aimed to investigate the promoting effect of Y-27632 on limbal epithelial cell proliferation. Limbal expla