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Sample records for cell proliferation regulation

  1. Negative regulators of cell proliferation

    Science.gov (United States)

    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.

  2. Regulation of cell proliferation by G proteins.

    Science.gov (United States)

    Dhanasekaran, N; Tsim, S T; Dermott, J M; Onesime, D

    1998-09-17

    G Proteins provide signal transduction mechanisms to seven transmembrane receptors. Recent studies have indicated that the alpha-subunits as well as the betagamma-subunits of these proteins regulate several critical signaling pathways involved in cell proliferation, differentiation and apoptosis. Of the 17 alpha-subunits that have been cloned, at least ten of them have been shown to couple mitogenic signaling in fibroblast cells. Activating mutations in G alpha(s), G alpha(i)2, and G alpha12 have been correlated with different types of tumors. In addition, the ability of the betagamma-subunits to activate mitogenic pathways in different cell-types has been defined. The present review briefly summarizes the diverse and novel signaling pathways regulated by the alpha- as well as the betagamma-subunits of G proteins in regulating cell proliferation. PMID:9779986

  3. Mitochondrial Regulation of Cell Cycle and Proliferation

    OpenAIRE

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

    2012-01-01

    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...

  4. Insulin and glucagon regulate pancreatic α-cell proliferation.

    Directory of Open Access Journals (Sweden)

    Zhuo Liu

    Full Text Available Type 2 diabetes mellitus (T2DM results from insulin resistance and β-cell dysfunction, in the setting of hyperglucagonemia. Glucagon is a 29 amino acid peptide hormone, which is secreted from pancreatic α cells: excessively high circulating levels of glucagon lead to excessive hepatic glucose output. We investigated if α-cell numbers increase in T2DM and what factor (s regulate α-cell turnover. Lepr(db/Lepr(db (db/db mice were used as a T2DM model and αTC1 cells were used to study potential α-cell trophic factors. Here, we demonstrate that in db/db mice α-cell number and plasma glucagon levels increased as diabetes progressed. Insulin treatment (EC50 = 2 nM of α cells significantly increased α-cell proliferation in a concentration-dependent manner compared to non-insulin-treated α cells. Insulin up-regulated α-cell proliferation through the IR/IRS2/AKT/mTOR signaling pathway, and increased insulin-mediated proliferation was prevented by pretreatment with rapamycin, a specific mTOR inhibitor. GcgR antagonism resulted in reduced rates of cell proliferation in αTC1 cells. In addition, blockade of GcgRs in db/db mice improved glucose homeostasis, lessened α-cell proliferation, and increased intra-islet insulin content in β cells in db/db mice. These studies illustrate that pancreatic α-cell proliferation increases as diabetes develops, resulting in elevated plasma glucagon levels, and both insulin and glucagon are trophic factors to α-cells. Our current findings suggest that new therapeutic strategies for the treatment of T2DM may include targeting α cells and glucagon.

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

    Science.gov (United States)

    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

  6. c-Myc regulates cell proliferation during lens development.

    Directory of Open Access Journals (Sweden)

    Gabriel R Cavalheiro

    Full Text Available Myc protooncogenes play important roles in the regulation of cell proliferation, growth, differentiation and survival during development. In various developing organs, c-myc has been shown to control the expression of cell cycle regulators and its misregulated expression is detected in many human tumors. Here, we show that c-myc gene (Myc is highly expressed in developing mouse lens. Targeted deletion of c-myc gene from head surface ectoderm dramatically impaired ocular organogenesis, resulting in severe microphtalmia, defective anterior segment development, formation of a lens stalk and/or aphakia. In particular, lenses lacking c-myc presented thinner epithelial cell layer and growth impairment that was detectable soon after its inactivation. Defective development of c-myc-null lens was not caused by increased cell death of lens progenitor cells. Instead, c-myc loss reduced cell proliferation, what was associated with an ectopic expression of Prox1 and p27(Kip1 proteins within epithelial cells. Interestingly, a sharp decrease in the expression of the forkhead box transcription factor Foxe3 was also observed following c-myc inactivation. These data represent the first description of the physiological roles played by a Myc family member in mouse lens development. Our findings support the conclusion that c-myc regulates the proliferation of lens epithelial cells in vivo and may, directly or indirectly, modulate the expression of classical cell cycle regulators in developing mouse lens.

  7. MAPK signal pathways in the regulation of cell proliferation in mammalian cells

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    MAPK families play an important role in complex cellular programs like proliferation, differentiation,development, transformation, and apoptosis. At least three MAPK families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.

  8. Metric dynamics for membrane transformation through regulated cell proliferation

    OpenAIRE

    Ito, Hiroshi C.

    2016-01-01

    This study develops an equation for describing three-dimensional membrane transformation through proliferation of its component cells regulated by morphogen density distributions on the membrane. The equation is developed in a two-dimensional coordinate system mapped on the membrane, referred to as the membrane coordinates. When the membrane expands, the membrane coordinates expand in the same manner so that the membrane is invariant in the coordinates. In the membrane coordinate system, the ...

  9. Matrix stiffness regulates endothelial cell proliferation through septin 9.

    Directory of Open Access Journals (Sweden)

    Yi-Ting Yeh

    Full Text Available Endothelial proliferation, which is an important process in vascular homeostasis, can be regulated by the extracellular microenvironment. In this study we demonstrated that proliferation of endothelial cells (ECs was enhanced on hydrogels with high stiffness (HSG, 21.5 kPa in comparison to those with low stiffness (LSG, 1.72 kPa. ECs on HSG showed markedly prominent stress fibers and a higher RhoA activity than ECs on LSG. Blockade of RhoA attenuated stress fiber formation and proliferation of ECs on HSG, but had little effect on ECs on LSG; enhancement of RhoA had opposite effects. The phosphorylations of Src and Vav2, which are positive RhoA upstream effectors, were higher in ECs on HSG. The inhibition of Src/Vav2 attenuated the HSG-mediated RhoA activation and EC proliferation but exhibited nominal effects on ECs on LSG. Septin 9 (SEPT9, the negative upstream effector for RhoA, was significantly higher in ECs on LSG. The inhibition of SEPT9 increased RhoA activation, Src/Vav2 phosphorylations, and EC proliferation on LSG, but showed minor effects on ECs on HSG. We further demonstrated that the inactivation of integrin α(vβ(3 caused an increase of SEPT9 expression in ECs on HSG to attenuate Src/Vav2 phosphorylations and inhibit RhoA-dependent EC proliferation. These results demonstrate that the SEPT9/Src/Vav2/RhoA pathway constitutes an important molecular mechanism for the mechanical regulation of EC proliferation.

  10. Matrix Stiffness Regulates Endothelial Cell Proliferation through Septin 9

    Science.gov (United States)

    Yeh, Yi-Ting; Hur, Sung Sik; Chang, Joann; Wang, Kuei-Chun; Chiu, Jeng-Jiann; Li, Yi-Shuan; Chien, Shu

    2012-01-01

    Endothelial proliferation, which is an important process in vascular homeostasis, can be regulated by the extracellular microenvironment. In this study we demonstrated that proliferation of endothelial cells (ECs) was enhanced on hydrogels with high stiffness (HSG, 21.5 kPa) in comparison to those with low stiffness (LSG, 1.72 kPa). ECs on HSG showed markedly prominent stress fibers and a higher RhoA activity than ECs on LSG. Blockade of RhoA attenuated stress fiber formation and proliferation of ECs on HSG, but had little effect on ECs on LSG; enhancement of RhoA had opposite effects. The phosphorylations of Src and Vav2, which are positive RhoA upstream effectors, were higher in ECs on HSG. The inhibition of Src/Vav2 attenuated the HSG-mediated RhoA activation and EC proliferation but exhibited nominal effects on ECs on LSG. Septin 9 (SEPT9), the negative upstream effector for RhoA, was significantly higher in ECs on LSG. The inhibition of SEPT9 increased RhoA activation, Src/Vav2 phosphorylations, and EC proliferation on LSG, but showed minor effects on ECs on HSG. We further demonstrated that the inactivation of integrin αvβ3 caused an increase of SEPT9 expression in ECs on HSG to attenuate Src/Vav2 phosphorylations and inhibit RhoA-dependent EC proliferation. These results demonstrate that the SEPT9/Src/Vav2/RhoA pathway constitutes an important molecular mechanism for the mechanical regulation of EC proliferation. PMID:23118862

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

    Science.gov (United States)

    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

  12. PPARδ regulates satellite cell proliferation and skeletal muscle regeneration

    Directory of Open Access Journals (Sweden)

    Angione Alison R

    2011-11-01

    Full Text Available Abstract Peroxisome proliferator-activated receptors (PPARs are a class of nuclear receptors that play important roles in development and energy metabolism. Whereas PPARδ has been shown to regulate mitochondrial biosynthesis and slow-muscle fiber types, its function in skeletal muscle progenitors (satellite cells is unknown. Since constitutive mutation of Pparδ leads to embryonic lethality, we sought to address this question by conditional knockout (cKO of Pparδ using Myf5-Cre/Pparδflox/flox alleles to ablate PPARδ in myogenic progenitor cells. Although Pparδ-cKO mice were born normally and initially displayed no difference in body weight, muscle size or muscle composition, they later developed metabolic syndrome, which manifested as increased body weight and reduced response to glucose challenge at age nine months. Pparδ-cKO mice had 40% fewer satellite cells than their wild-type littermates, and these satellite cells exhibited reduced growth kinetics and proliferation in vitro. Furthermore, regeneration of Pparδ-cKO muscles was impaired after cardiotoxin-induced injury. Gene expression analysis showed reduced expression of the Forkhead box class O transcription factor 1 (FoxO1 gene in Pparδ-cKO muscles under both quiescent and regenerating conditions, suggesting that PPARδ acts through FoxO1 in regulating muscle progenitor cells. These results support a function of PPARδ in regulating skeletal muscle metabolism and insulin sensitivity, and they establish a novel role of PPARδ in muscle progenitor cells and postnatal muscle regeneration.

  13. Leading research on cell proliferation regulation technology; Saibo zoshoku seigyo gijutsu no sendo kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    For developing intelligent material, animal test alternative model, bio-cell analysis equipment, self-controlling bio-reactor and medical material, development of functional cells was studied by cell proliferation regulation technology. In fiscal 1996, the expression analysis and separation technology of specific gene for cell proliferation, and the intracellular regulation technology were surveyed from the viewpoint of intracellular regulation. The cell proliferation regulation technology by specific regulating material of cells, extracellular matrix, coculture system and embryonic cell was surveyed from the viewpoint of extracellular regulation. In addition, based on these survey results, new cell culture/analysis technology, new bio-material, artificial organ system, energy saving bio-reactor, environment purification microorganism, and animal test alternative model were surveyed as applications to industrial basic technologies from a long-term viewpoint. The approach to cell proliferation regulation requires preparation of a concrete proliferation regulation technology system of cells, and concrete application targets. 268 refs., 43 figs., 4 tabs.

  14. Expression Profile of microRNAs Regulating Proliferation and Differentiation in Mouse Adult Cardiac Stem Cells

    OpenAIRE

    Brás-Rosário, Luis; Matsuda, Alex; Pinheiro, Ana Isabel; Gardner, Rui; Lopes, Telma; Amaral, Andreia; Gama-Carvalho, Margarida

    2013-01-01

    The identification of cardiac cells with stem cell properties changed the paradigm of the heart as a post mitotic organ. These cells proliferate and differentiate into cardiomyocytes, endothelial and vascular smooth muscle cells, providing for cardiac cell homeostasis and regeneration. microRNAs are master switches controlling proliferation and differentiation, in particular regulating stem cell biology and cardiac development. Modulation of microRNAs -regulated gene expression networks holds...

  15. NSA2, a novel nucleolus protein regulates cell proliferation and cell cycle

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Heyu [Department of Immunology, School of Basic Medical Sciences, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); Human Disease Genomics Center, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); Ma, Xi [Department of Immunology, School of Basic Medical Sciences, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); Human Disease Genomics Center, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); State Key Lab of Animal Nutrition, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193 (China); Shi, Taiping [Chinese National Human Genome Center, Beijing. 3-707 North YongChang Road BDA, Beijing 100176 (China); Song, Quansheng [Department of Immunology, School of Basic Medical Sciences, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); Human Disease Genomics Center, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); Zhao, Hongshan, E-mail: hongshan@bjmu.edu.cn [Department of Immunology, School of Basic Medical Sciences, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); Human Disease Genomics Center, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); Ma, Dalong [Department of Immunology, School of Basic Medical Sciences, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China); Human Disease Genomics Center, Peking University, No. 38 Xueyuan Road, Beijing 100191 (China)

    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.

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-05-02

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Cheng, Jung-Chien [Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Huang, He-Feng, E-mail: huanghefg@hotmail.com [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Leung, Peter C.K., E-mail: peter.leung@ubc.ca [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada)

    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.

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

    Science.gov (United States)

    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.

  1. TGF-β Signaling Regulates Pancreatic β-Cell Proliferation through Control of Cell Cycle Regulator p27 Expression

    International Nuclear Information System (INIS)

    Proliferation of pancreatic β-cells is an important mechanism underlying β-cell mass adaptation to metabolic demands. Increasing β-cell mass by regeneration may ameliorate or correct both type 1 and type 2 diabetes, which both result from inadequate production of insulin by β-cells of the pancreatic islet. Transforming growth factor β (TGF-β) signaling is essential for fetal development and growth of pancreatic islets. In this study, we exposed HIT-T15, a clonal pancreatic β-cell line, to TGF-β signaling. We found that inhibition of TGF-β signaling promotes proliferation of the cells significantly, while TGF-β signaling stimulation inhibits proliferation of the cells remarkably. We confirmed that this proliferative regulation by TGF-β signaling is due to the changed expression of the cell cycle regulator p27. Furthermore, we demonstrated that there is no observed effect on transcriptional activity of p27 by TGF-β signaling. Our data show that TGF-β signaling mediates the cell-cycle progression of pancreatic β-cells by regulating the nuclear localization of CDK inhibitor, p27. Inhibition of TGF-β signaling reduces the nuclear accumulation of p27, and as a result this inhibition promotes proliferation of β-cells

  2. Swelling-activated ion channels: functional regulation in cell-swelling, proliferation and apoptosis

    DEFF Research Database (Denmark)

    Stutzin, A; Hoffmann, E K

    2006-01-01

    Cell volume regulation is one of the most fundamental homeostatic mechanisms and essential for normal cellular function. At the same time, however, many physiological mechanisms are associated with regulatory changes in cell size meaning that the set point for cell volume regulation is under phys...... as key players in the maintenance of normal steady-state cell volume, with particular emphasis on the intracellular signalling pathways responsible for their regulation during hypotonic stress, cell proliferation and apoptosis....

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

    Science.gov (United States)

    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. Expression profile of microRNAs regulating proliferation and differentiation in mouse adult cardiac stem cells.

    Directory of Open Access Journals (Sweden)

    Luis Brás-Rosário

    Full Text Available The identification of cardiac cells with stem cell properties changed the paradigm of the heart as a post mitotic organ. These cells proliferate and differentiate into cardiomyocytes, endothelial and vascular smooth muscle cells, providing for cardiac cell homeostasis and regeneration. microRNAs are master switches controlling proliferation and differentiation, in particular regulating stem cell biology and cardiac development. Modulation of microRNAs -regulated gene expression networks holds the potential to control cell fate and proliferation, with predictable biotechnologic and therapeutic applications. To obtain insights into the regulatory networks active in cardiac stem cells, we characterized the expression profile of 95 microRNAs with reported functions in stem cell and tissue differentiation in mouse cardiac stem cells, and compared it to that of mouse embryonic heart and mesenchymal stem cells. The most highly expressed microRNAs identified in cardiac stem cells are known to target key genes involved in the control of cell proliferation and adhesion, vascular function and cardiomyocyte differentiation. We report a subset of differentially expressed microRNAs that are proposed to act as regulators of differentiation and proliferation of adult cardiac stem cells, providing novel insights into active gene expression networks regulating their biological properties.

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

    Science.gov (United States)

    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

  6. Neuron-NG2 Cell Synapses: Novel Functions for Regulating NG2 Cell Proliferation and Differentiation

    Directory of Open Access Journals (Sweden)

    Qian-Kun Yang

    2013-01-01

    Full Text Available NG2 cells are a population of CNS cells that are distinct from neurons, mature oligodendrocytes, astrocytes, and microglia. These cells can be identified by their NG2 proteoglycan expression. NG2 cells have a highly branched morphology, with abundant processes radiating from the cell body, and express a complex set of voltage-gated channels, AMPA/kainate, and GABA receptors. Neurons notably form classical and nonclassical synapses with NG2 cells, which have varied characteristics and functions. Neuron-NG2 cell synapses could fine-tune NG2 cell activities, including the NG2 cell cycle, differentiation, migration, and myelination, and may be a novel potential therapeutic target for NG2 cell-related diseases, such as hypoxia-ischemia injury and periventricular leukomalacia. Furthermore, neuron-NG2 cell synapses may be correlated with the plasticity of CNS in adulthood with the synaptic contacts passing onto their progenies during proliferation, and synaptic contacts decrease rapidly upon NG2 cell differentiation. In this review, we highlight the characteristics of classical and nonclassical neuron-NG2 cell synapses, the potential functions, and the fate of synaptic contacts during proliferation and differentiation, with the emphasis on the regulation of the NG2 cell cycle by neuron-NG2 cell synapses and their potential underlying mechanisms.

  7. Nitric oxide modulates hypoxic pulmonary smooth muscle cell proliferation and apoptosis by regulating carbon monoxide pathway

    Institute of Scientific and Technical Information of China (English)

    Yan-fei WANG; Hong TIAN; Chao-shu TANG; Hong-fang JIN; Jun-bao DU

    2007-01-01

    Aim: To explore the role of carbon monoxide (CO) in the regulation of hypoxic pulmonary artery smooth muscle cell (PASMC) proliferation and apoptosis by nitric oxide (NO). Methods: PASMC of Wistar rats was cultured in vitro in the presence of a NO donor, sodium nitroprusside, or an inhibitor of heme oxygenase (HO), zinc protoporphyrin-IX, or under both normoxic and hypoxic conditions.Nitrite and carboxyhemoglobin in PASMC medium were detected with spectrophotometry. The proliferating and apoptotic percentage of PASMC was measured by flow cytometry. The expression of HO-1 mRNA in PASMC was analyzed by fluorescent real-time quantitative PCR, and the proliferating cell nuclear antigen and caspase-3 were examined by immunocytochemical analysis. Results: The results showed that hypoxia suppressed NO generation from PASMC, which promoted hypoxic PASMC proliferation and induced apoptosis. Meanwhile, hy-poxia induced HO-1 expression in PASMC and promoted CO production from PASMC, which inhibited PASMC proliferation and regulated PASMC apoptosis. NO upregulated the expression of HO-1 mRNA in hypoxic PASMC; NO also inhib-ited proliferation and promoted apoptosis of hypoxic PASMC, possibly by regu-lating the production of CO. Conclusion: The results indicated that CO could inhibit proliferation and regulate apoptosis of PASMC, and NO inhibited prolifera-tion and promoted apoptosis of hypoxic PASMC, possibly by regulating the pro-duction of CO.

  8. BDNF, produced by a TPO-stimulated megakaryocytic cell line, regulates autocrine proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Shogo [Graduate School of Health Sciences, Hokkaido University, Sapporo (Japan); Research Fellow of the Japan Society for the Promotion of Science, Tokyo (Japan); Nagasawa, Ayumi; Masuda, Yuya; Tsunematsu, Tetsuya [Graduate School of Health Sciences, Hokkaido University, Sapporo (Japan); Hayasaka, Koji; Matsuno, Kazuhiko; Shimizu, Chikara [Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo (Japan); Ozaki, Yukio [Department of Clinical and Laboratory Medicine, Faculty of Medicine, University of Yamanashi (Japan); Moriyama, Takanori, E-mail: moriyama@hs.hokuda.ac.jp [Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Sapporo (Japan)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer It has been thought that BDNF is not produced in the megakaryocytic lineage. Black-Right-Pointing-Pointer MEG-01 produces BDNF upon TPO stimulation and regulates its proliferation. Black-Right-Pointing-Pointer BDNF accelerates proliferation of MEG-01 in an autocrine manner. Black-Right-Pointing-Pointer BDNF may be an autocrine MEG-CSF, which regulates megakaryopoiesis. -- Abstract: While human platelets release endogenous brain-derived neurotrophic factor (BDNF) upon activation, a previous report on MEG-01, a megakaryocytic cell line, found no trace of BDNF production, and the pathophysiological function of platelet BDNF has remained elusive. In the present study, we demonstrate that MEG-01 produces BDNF in the presence of TPO and that this serves to potentiate cell proliferation. Our in vitro findings suggest that BDNF regulates MEG-01 proliferation in an autocrine manner, and we suggest that BDNF may be a physiological autocrine regulator of megakaryocyte progenitors.

  9. Folate receptor {alpha} regulates cell proliferation in mouse gonadotroph {alpha}T3-1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Congjun; Evans, Chheng-Orn [Department of Neurosurgery and Laboratory of Molecular Neurosurgery and Biotechnology, Emory University, School of Medicine, Atlanta, Georgia (United States); Stevens, Victoria L. [Epidemiology and Surveillance Research, American Cancer Society, Atlanta, Georgia (United States); Owens, Timothy R. [Emory University, School of Medicine, Atlanta, Georgia (United States); Oyesiku, Nelson M., E-mail: noyesik@emory.edu [Department of Neurosurgery and Laboratory of Molecular Neurosurgery and Biotechnology, Emory University, School of Medicine, Atlanta, Georgia (United States)

    2009-11-01

    We have previously found that the mRNA and protein levels of the folate receptor alpha (FR{alpha}) are uniquely over-expressed in clinically human nonfunctional (NF) pituitary adenomas, but the mechanistic role of FR{alpha} has not fully been determined. We investigated the effect of FR{alpha} over-expression in the mouse gonadotroph {alpha}T3-1 cell line as a model for NF pituitary adenomas. We found that the expression and function of FR{alpha} were strongly up-regulated, by Western blotting and folic acid binding assay. Furthermore, we found a higher cell growth rate, an enhanced percentage of cells in S-phase by BrdU assay, and a higher PCNA staining. These observations indicate that over-expression of FR{alpha} promotes cell proliferation. These effects were abrogated in the same {alpha}T3-1 cells when transfected with a mutant FR{alpha} cDNA that confers a dominant-negative phenotype by inhibiting folic acid binding. Finally, by real-time quantitative PCR, we found that mRNA expression of NOTCH3 was up-regulated in FR{alpha} over-expressing cells. In summary, our data suggests that FR{alpha} regulates pituitary tumor cell proliferation and mechanistically may involve the NOTCH pathway. Potentially, this finding could be exploited to develop new, innovative molecular targeted treatment for human NF pituitary adenomas.

  10. Folate receptor α regulates cell proliferation in mouse gonadotroph αT3-1 cells

    International Nuclear Information System (INIS)

    We have previously found that the mRNA and protein levels of the folate receptor alpha (FRα) are uniquely over-expressed in clinically human nonfunctional (NF) pituitary adenomas, but the mechanistic role of FRα has not fully been determined. We investigated the effect of FRα over-expression in the mouse gonadotroph αT3-1 cell line as a model for NF pituitary adenomas. We found that the expression and function of FRα were strongly up-regulated, by Western blotting and folic acid binding assay. Furthermore, we found a higher cell growth rate, an enhanced percentage of cells in S-phase by BrdU assay, and a higher PCNA staining. These observations indicate that over-expression of FRα promotes cell proliferation. These effects were abrogated in the same αT3-1 cells when transfected with a mutant FRα cDNA that confers a dominant-negative phenotype by inhibiting folic acid binding. Finally, by real-time quantitative PCR, we found that mRNA expression of NOTCH3 was up-regulated in FRα over-expressing cells. In summary, our data suggests that FRα regulates pituitary tumor cell proliferation and mechanistically may involve the NOTCH pathway. Potentially, this finding could be exploited to develop new, innovative molecular targeted treatment for human NF pituitary adenomas.

  11. SAMHD1 is down regulated in lung cancer by methylation and inhibits tumor cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jia-lei [Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai 200032 (China); Lu, Fan-zhen [Department of Thoracic Surgery, The Huadong Hospital, Fudan University, Shanghai 200040 (China); Shen, Xiao-Yong, E-mail: shengxiaoyong_sh@163.com [Department of Thoracic Surgery, The Huadong Hospital, Fudan University, Shanghai 200040 (China); Wu, Yun, E-mail: WuYun_hd@163.com [Department of Thoracic Surgery, The Huadong Hospital, Fudan University, Shanghai 200040 (China); Zhao, Li-ting [Department of Thoracic Surgery, The Huadong Hospital, Fudan University, Shanghai 200040 (China)

    2014-12-12

    Highlights: • SAMHD1 expression level is down regulated in lung adenocarcinoma. • The promoter of SAMHD1 is methylated in lung adenocarcinoma. • Over expression of SAMHD1 inhibits the proliferation of lung cancer cells. - Abstract: The function of dNTP hydrolase SAMHD1 as a viral restriction factor to inhibit the replication of several viruses in human immune cells was well established. However, its regulation and function in lung cancer have been elusive. Here, we report that SAMHD1 is down regulated both on protein and mRNA levels in lung adenocarcinoma compared to adjacent normal tissue. We also found that SAMHD1 promoter is highly methylated in lung adenocarcinoma, which may inhibit its gene expression. Furthermore, over expression of the SAMHD1 reduces dNTP level and inhibits the proliferation of lung tumor cells. These results reveal the regulation and function of SAMHD1 in lung cancer, which is important for the proliferation of lung tumor cells.

  12. Mechanisms of regulating cell topology in proliferating epithelia: impact of division plane, mechanical forces, and cell memory.

    Directory of Open Access Journals (Sweden)

    Yingzi Li

    Full Text Available 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.

  13. Mechanisms of regulating cell topology in proliferating epithelia: impact of division plane, mechanical forces, and cell memory.

    Science.gov (United States)

    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.

  14. Tetrahydrouridine inhibits cell proliferation through cell cycle regulation regardless of cytidine deaminase expression levels.

    Directory of Open Access Journals (Sweden)

    Naotake Funamizu

    Full Text Available Tetrahydrouridine (THU is a well characterized and potent inhibitor of cytidine deaminase (CDA. Highly expressed CDA catalyzes and inactivates cytidine analogues, ultimately contributing to increased gemcitabine resistance. Therefore, a combination therapy of THU and gemcitabine is considered to be a potential and promising treatment for tumors with highly expressed CDA. In this study, we found that THU has an alternative mechanism for inhibiting cell growth which is independent of CDA expression. Three different carcinoma cell lines (MIAPaCa-2, H441, and H1299 exhibited decreased cell proliferation after sole administration of THU, while being unaffected by knocking down CDA. To investigate the mechanism of THU-induced cell growth inhibition, cell cycle analysis using flow cytometry was performed. This analysis revealed that THU caused an increased rate of G1-phase occurrence while S-phase occurrence was diminished. Similarly, Ki-67 staining further supported that THU reduces cell proliferation. We also found that THU regulates cell cycle progression at the G1/S checkpoint by suppressing E2F1. As a result, a combination regimen of THU and gemcitabine might be a more effective therapy than previously believed for pancreatic carcinoma since THU works as a CDA inhibitor, as well as an inhibitor of cell growth in some types of pancreatic carcinoma cells.

  15. Regulation of progenitor cell proliferation and neuronal differentiation in enteric nervous system neurospheres.

    Directory of Open Access Journals (Sweden)

    Sokratis Theocharatos

    Full Text Available Enteric nervous system (ENS progenitor cells isolated from mouse and human bowel can be cultured in vitro as neurospheres which are aggregates of the proliferating progenitor cells, together with neurons and glial cells derived from them. To investigate the factors regulating progenitor cell proliferation and differentiation, we first characterised cell proliferation in mouse ENS neurospheres by pulse chase experiments using thymidine analogs. We demonstrate rapid and continuous cell proliferation near the neurosphere periphery, after which postmitotic cells move away from the periphery to become distributed throughout the neurosphere. While many proliferating cells expressed glial markers, expression of the neuronal markers β-tubulin III (Tuj1 and nitric oxide synthase was detected in increasing numbers of post-mitotic cells after a delay of several days. Treatment of both mouse and human neurospheres with the γ-secretase inhibitor N-[N-(3,5-Difluorophenacetyl-L-alanyl]-S-phenylglycine t-butyl ester (DAPT reduced expression of the transcription factors Hes1 and Hes5, demonstrating inhibition of Notch signaling. DAPT treatment also inhibited progenitor cell proliferation and increased the numbers of differentiating neurons expressing Tuj1 and nitric oxide synthase. To confirm that the cellular effects of DAPT treatment were due to inhibition of Notch signaling, siRNA knockdown of RBPjκ, a key component of the canonical Notch signaling pathway, was demonstrated both to reduce proliferation and to increase neuronal differentiation in neurosphere cells. These observations indicate that Notch signaling promotes progenitor cell proliferation and inhibits neuronal differentiation in ENS neurospheres.

  16. p66Shc longevity protein regulates the proliferation of human ovarian cancer cells.

    Science.gov (United States)

    Muniyan, Sakthivel; Chou, Yu-Wei; Tsai, Te-Jung; Thomes, Paul; Veeramani, Suresh; Benigno, Benedict B; Walker, L DeEtte; McDonald, John F; Khan, Shafiq A; Lin, Fen-Fen; Lele, Subodh M; Lin, Ming-Fong

    2015-08-01

    p66Shc functions as a longevity protein in murine and exhibits oxidase activity in regulating diverse biological activities. In this study, we investigated the role of p66Shc protein in regulating ovarian cancer (OCa) cell proliferation. Among three cell lines examined, the slowest growing OVCAR-3 cells have the lowest level of p66Shc protein. Transient transfection with p66Shc cDNA expression vector in OVCAR-3 cells increases cell proliferation. Conversely, knock-down of p66Shc by shRNA in rapidly growing SKOV-3 cells results in decreased cell growth. In estrogen (E2)-treated CaOV-3 cells, elevated p66Shc protein level correlates with ROS level, ErbB-2 and ERK/MAPK activation, and cell proliferation. Further, the E2-stimulated proliferation of CaOV-3 cells was blocked by antioxidants and ErbB-2 inhibitor. Additionally, in E2-stimulated cells, the tartrate-sensitive, but not the tartrate-resistant, phosphatase activity decreases; concurrently, the tyrosine phosphorylation of ErbB-2 increases. Conversely, inhibition of phosphatase activity by L(+)-tartrate treatment increases p66Shc protein level, ErbB-2 tyrosine phosphorylation, ERK/MAPK activation, and cell growth. Further, inhibition of the ERK/MAPK pathway by PD98059 blocks E2-induced ERK/MAPK activation and cell proliferation in CaOV-3 cells. Moreover, immunohistochemical analyses showed that the p66Shc protein level was significantly higher in cancerous cells than in noncancerous cells in archival OCa tissues (n = 76; P = 0.00037). These data collectively indicate that p66Shc protein plays a critical role in up-regulating OCa progression. PMID:24395385

  17. Moclobemide up-regulates proliferation of hippocampal progenitor cells in chronically stressed mice

    Institute of Scientific and Technical Information of China (English)

    Yun-feng LI; You-zhi ZHANG; Yan-qin LIU; Heng-lin WANG; Li YUAN; Zhi-pu LUO

    2004-01-01

    AIM: To explore the action mechanism of antidepressants. METHODS: The PC12 cell proliferation was detected by flow cytometry,. The proliferation of hippocampal progenitor cells and level of brain-derived neurotrophic factor (BDNF) were measured by immunohistochemistry. RESULTS: Treatment with N-methylaspartate (NMDA)600 μmol/L for 3 d significantly decreased the percentage of S-phase in PC12 cells, while in the presence of classical antidepressant, moclobemide (MOC) 2 and 10 μmol/L, the percentage in S-phase increased. Furthermore,the proliferation of progenitor cells in hippocampal dentate gyrus (subgranular zone), as well as the level of BDNF in hippocampus significantly decreased in chronically stressed mice, while chronic administration with MOC 40mg/kg (ip) up-regulated the progenitor cell proliferation and BDNF level in the same time course. CONLUSION:Up-regulation of the proliferation of hippocampal progenitor cells is one of the action mechanisms for MOC, which may be closely related to the elevation of BDNF level at the same time. These results also extend evidence for our hypothesis that up-regulation of the hippocampal neurogenesis is one of the common mechanisms for antidepressants.

  18. Moclobemide up-regulates proliferation of hippocampal progenitor cells in chronically stressed mice

    Institute of Scientific and Technical Information of China (English)

    Yun-fengLI; You-zhiZHANG; Yan-qinLIU; Heng-linWANG; LiYUAN; Zhi-puLUO

    2004-01-01

    AIM: To explore the action mechanism of antidepressants. METHODS: The PC 12 cell proliferation was detected by flow cytometry,. The proliferation of hippocampal progenitor cells and level of brain-derived neurotrophic factor (BDNF) were measured by immunohistochemistry. RESULTS: Treatment with N-methylaspartate (NMDA)600 μmol/L for 3 d significantly decreased the percentage of S-phase in PC12 cells, while in the presence of classical antidepressant, moclobemide (MOC) 2 and 10 μnol/L, the percentage in S-phase increased. Furthermore,the proliferation of progenitor cells in hippocampal dentate gyrus (subgranular zone), as well as the level of BDNF in hippocampus significantly decreased in chronically stressed mice, while chronic administration with MOC 40 mg/kg (ip) up-regulated the progenitor cell proliferation and BDNF level in the same time course. CONLUSION:Up-regulation of the proliferation of hippocampal progenitor cells is one of the action mechanisms for MOC, which may be closely related to the elevation of BDNF level at the same time. These results also extend evidence for our hypothesis that up-regulation of the hippocampal neurogenesis is one of the common mechanisms for antidepressants.

  19. The mitochondrial phospholipid cardiolipin is involved in the regulation of T-cell proliferation.

    Science.gov (United States)

    Mürke, Eik; Stoll, Steffan; Lendeckel, Uwe; Reinhold, Dirk; Schild, Lorenz

    2016-08-01

    Challenge of the immune system with antigens induces a cascade of processes including activation of naïve T cells, induction of proliferation, differentiation into effector cells and finally contraction via apoptosis. To meet the dynamic requirements of an adequate immune response, T cells must metabolically adapt to actual situations by switching between catabolic and anabolic metabolism. In this context mitochondria are hubs of metabolic regulation. The phospholipid cardiolipin (CL) is crucial for the structural and functional integrity and, thus, the metabolism of mitochondria. The aim of this study was to verify a possible interrelationship between T cell proliferation and CL composition. For this purpose, we adjusted the proliferation of peripheral human T cells from volunteers by stimulation with different concentrations of the mitogen phytohaemagglutinin (PHA), inhibition with Cyclosporin A (CsA) and exposure of cells to different free fatty acids and subsequently analysed the composition of CL by LC/MS/MS spectroscopy. All of the treatments had significant effects on CL composition. Correlation analysis of the proliferation rate and CL composition revealed that only the amount of incorporated palmitoleic acid and the content of tetralinoleoyl-CL are significantly associated with the proliferation rate. This observation is strongly suggestive of a regulatory function of these particular CL components/species in the process of T cell proliferation. As CL is crucially involved in mitochondrial function one can speculate that changes in CL composition contribute to vital mitochondria-dependent adaptations of energy metabolism in T cells during immune response. PMID:27163692

  20. Regulation of IL-2 induced proliferation and cytotoxicity in human natural killer cells by monoclonal antibodies

    International Nuclear Information System (INIS)

    Natural killer (NK) activity is mediated by a subpopulation of cells termed large granular lymphocytes (LGL), which exhibit cytotoxic activity against a variety of tumor targets. LGL express OKT8, OKT9, OKT10, OKT11, 3G8 (FcγR), OKM1, NKH1. The addition of recombinant IL-2 (rIL-2), increases cytotoxicity, induces IFN-γ production and leads to LGL proliferation. Since monoclonal antibodies (MoAb) represent highly specific probes to analyze possible surface molecules, they have studied the role of various MoAbs in the regulation of cytotoxicity, proliferation, and secretory function of purified LGL. LGL were isolated from nonadherent human peripheral blood leukocytes on discontinuous Percoll density gradients, followed by 290C E-rosette depletion of contaminating T cells. These preparations were ≥ 85% LGL and contained ≥ 5% OKT3+ cells. Using a limiting dilution assay, purified LGL were incubated with rIL-2 and the MoAbs (10 μg/ml) for 7 days. These cells were tested for cytotoxicity against K562 in a 51Cr- release assay, and for proliferation as determined by 3H-thymidine incorporation. Results indicate that the OKT9 antibody inhibited both the cytotoxicity and proliferation. MoAb against LGl markers (OKT11, OKT8, OKM1, 3G8, and NKH1) had no effect on cytotoxicity or proliferation. Unlike the T cell receptor complex (with OKT3), the surface molecules examined do not regulate LGL lysis or proliferation

  1. ST13, a proliferation regulator, inhibits growth and migration of colorectal cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Rui BAI; Zhong SHI; Jia-wei ZHANG; Dan LI; Yong-liang ZHU; Shu ZHENG

    2012-01-01

    Background and objective:ST13,is the gene encoding the HSP70 interacting protein (HIP).Previous research has shown that ST13 mRNA and protein levels are down-regulated in colorectal cancer (CRC) tissues compared with adjacent normal tissues.This study aims at the role of ST13 in the proliferation and migration of CRC cells.Methods:The transcript level of ST13 in different CRC cell lines was evaluated by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR).ST13-overexpressed and ST13-knockdown CRC cells were constructed respectively by lentiviral transduction,followed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay,plate colony formation,cell-cycle analysis,and migration assays to evaluate the influence of ST13 on proliferation and migration in vitro.Moreover,a mouse xenograft study was performed to test in vivo tumorigenicity of ST13-knockdown CRC cells.Results:Lentivirus-mediated overexpression of ST13 in CRC cells inhibited cell proliferation,colony formation,and cell migration in vitro.In contrast,down-regulation of ST13 by lentiviralbased short hairpin RNA (shRNA) interference in CRC cells significantly increased cell proliferation and cloning efficiency in vitro.In addition,down-regulation of ST13 expression significantly increased the tumorigenicity of CRC cells in vivo.Conclusions:ST13 gene is a proliferation regulator that inhibits tumor growth in CRC and may affect cell migration.

  2. Regulation of pituitary hormones and cell proliferation by components of the extracellular matrix

    Directory of Open Access Journals (Sweden)

    M. Paez-Pereda

    2005-10-01

    Full Text Available The extracellular matrix is a three-dimensional network of proteins, glycosaminoglycans and other macromolecules. It has a structural support function as well as a role in cell adhesion, migration, proliferation, differentiation, and survival. The extracellular matrix conveys signals through membrane receptors called integrins and plays an important role in pituitary physiology and tumorigenesis. There is a differential expression of extracellular matrix components and integrins during the pituitary development in the embryo and during tumorigenesis in the adult. Different extracellular matrix components regulate adrenocorticotropin at the level of the proopiomelanocortin gene transcription. The extracellular matrix also controls the proliferation of adrenocorticotropin-secreting tumor cells. On the other hand, laminin regulates the production of prolactin. Laminin has a dynamic pattern of expression during prolactinoma development with lower levels in the early pituitary hyperplasia and a strong reduction in fully grown prolactinomas. Therefore, the expression of extracellular matrix components plays a role in pituitary tumorigenesis. On the other hand, the remodeling of the extracellular matrix affects pituitary cell proliferation. Matrix metalloproteinase activity is very high in all types of human pituitary adenomas. Matrix metalloproteinase secreted by pituitary cells can release growth factors from the extracellular matrix that, in turn, control pituitary cell proliferation and hormone secretion. In summary, the differential expression of extracellular matrix components, integrins and matrix metalloproteinase contributes to the control of pituitary hormone production and cell proliferation during tumorigenesis.

  3. RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Houcai; Yu, Jing; Zhang, Lixia; Xiong, Yuanyuan; Chen, Shuying; Xing, Haiyan; Tian, Zheng; Tang, Kejing; Wei, Hui; Rao, Qing; Wang, Min; Wang, Jianxiang, E-mail: wangjx@ihcams.ac.cn

    2014-04-18

    Highlights: • RPS27a expression was up-regulated in advanced-phase CML and AL patients. • RPS27a knockdown changed biological property of K562 and K562/G01 cells. • RPS27a knockdown affected Raf/MEK/ERK, P21 and BCL-2 signaling pathways. • RPS27a knockdown may be applicable for new combination therapy in CML patients. - Abstract: Ribosomal protein S27a (RPS27a) could perform extra-ribosomal functions besides imparting a role in ribosome biogenesis and post-translational modifications of proteins. The high expression level of RPS27a was reported in solid tumors, and we found that the expression level of RPS27a was up-regulated in advanced-phase chronic myeloid leukemia (CML) and acute leukemia (AL) patients. In this study, we explored the function of RPS27a in leukemia cells by using CML cell line K562 cells and its imatinib resistant cell line K562/G01 cells. It was observed that the expression level of RPS27a was high in K562 cells and even higher in K562/G01 cells. Further analysis revealed that RPS27a knockdown by shRNA in both K562 and K562G01 cells inhibited the cell viability, induced cell cycle arrest at S and G2/M phases and increased cell apoptosis induced by imatinib. Combination of shRNA with imatinib treatment could lead to more cleaved PARP and cleaved caspase-3 expression in RPS27a knockdown cells. Further, it was found that phospho-ERK(p-ERK) and BCL-2 were down-regulated and P21 up-regulated in RPS27a knockdown cells. In conclusion, RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells. It appears that drugs targeting RPS27a combining with tyrosine kinase inhibitor (TKI) might represent a novel therapy strategy in TKI resistant CML patients.

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

    International Nuclear Information System (INIS)

    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

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

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    Liu, Yang, E-mail: Ly10160624@163.com; Han, Dong, E-mail: Donghan@bjmu.edu.cn; Wang, Lei, E-mail: wanglei_dentist@163.com; Feng, Hailan, E-mail: kqfenghl@bjmu.edu.cn

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

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    Fan, Jun; Sun, Zhongjie

    2016-06-01

    Klotho was originally discovered as an aging-suppressor gene. The purpose of this study was to investigate whether secreted Klotho (SKL) affects the proliferation and differentiation of adipose-derived stem cells (ADSCs). RT-PCR and Western blot analysis showed that short-form Klotho was expressed in mouse ADSCs. The Klotho gene mutation KL(-/-) significantly decreased proliferation of ADSCs and expression of pluripotent transcription factors (Nanog, Sox-2, and Oct-4) in mice. The adipogenic differentiation of ADSCs was also decreased in KL(-/-) mice. Incubation with Klotho-deficient medium decreased ADSC proliferation, pluripotent transcription factor levels, and adipogenic differentiation, which is similar to what was found in KL(-/-) mice. These results indicate that Klotho deficiency suppresses ADSC proliferation and differentiation. Interestingly, treatment with recombinant SKL protein rescued the Klotho deficiency-induced impairment in ADSC proliferation and adipogenic differentiation. SKL also regulated ADSCs' differentiation to other cell lineages (osteoblasts, myofibroblasts), indicating that SKL maintains stemness of ADSCs. It is intriguing that overexpression of SKL significantly increased PPAR-γ expression and lipid formation in ADSCs following adipogenic induction, indicating enhanced adipogenic differentiation. Overexpression of SKL inhibited expression of TGFβ1 and its downstream signaling mediator Smad2/3. This study demonstrates, for the first time, that SKL is essential to the maintenance of normal proliferation and differentiation in ADSCs. Klotho regulates adipogenic differentiation in ADSCs, likely via inhibition of TGFβ1 and activation of PPAR-γ. Stem Cells 2016;34:1615-1625. PMID:26865060

  7. RhoC regulates the proliferation of gastric cancer cells through interaction with IQGAP1.

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    Yan Wu

    Full Text Available Our previous research results showed that both Ras homolog family member C (RhoC and IQ-domain GTPase-activating protein 1 (IQGAP1 were over-expressed in gastric cancer tissues and cells, but their role in tumorigenensis has not been addressed clearly. Herein we reported the proliferation stimulating effect of RhoC and IQGAP1 on gastric cancer cells and the interaction between two proteins in regulating the proliferation of gastric cancer cells. Plasmids and viral constructs encoding target siRNA and DNA were used to alter the expression of RhoC and IQGAP1. MTT method and BrdU incorporation assay were used for analyzing the effect of RhoC and different structures of IQGAP1 on proliferation. Protein levels of IQGAP1 and RhoC in cell lines were detected by Western blotting. Immunofluorescence and Co-Immunoprecipitation assays were applied to investigate the localization and binding between RhoC and IQGAP1. The results showed that RhoC, IQGAP1 and the C-terminal fragment of IQGAP1 significantly stimulated the proliferation of gastric cancer cells, and enhanced the expression of cyclin E and cyclin D1. By contrast, reduction of endogenous IQGAP1 or RhoC by siRNA attenuated cell proliferation. The depletion of IQGAP1 expression by siRNA significantly blocked the proliferative activity of constitutively active RhoC, while RhoC silencing by siRNA had no effect on IQGAP1-induced proliferation in gastric cancer cells. Co-immunoprecipitation and Immunofluorescence assays showed that RhoC and IQGAP1 bound each other. In conclusion, our results suggest that RhoC stimulates the proliferation of gastric cancer cells through recruiting IQGAP1 as an effector.

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

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    Abir Mukherjee

    2015-09-01

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

  9. Adrenomedullin and adrenotensin regulate collagen synthesis and proliferation in pulmonary arterial smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, W. [School of Control Science and Engineering, Biomedical Engineering Institute, Shandong University, Jinan, Shandong (China); Kong, Q.Y.; Zhao, C.F. [Department of Pediatrics, Qilu Hospital, Shandong University, Jinan, Shandong (China); Zhao, F. [Department of Medicine, Weill Medical College of Cornell University, New York, NY (United States); Li, F.H.; Xia, W. [Department of Pediatrics, Qilu Hospital, Shandong University, Jinan, Shandong (China); Wang, R. [Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital, Shandong University, Jinan, Shandong (China); Hu, Y.M. [School of Control Science and Engineering, Biomedical Engineering Institute, Shandong University, Jinan, Shandong (China); Hua, M. [Shandong Institute of Scientific and Technical Information, Jinan, Shandong (China)

    2013-12-10

    To understand the pathophysiological mechanisms of pulmonary arterial smooth muscle cell (PASMC) proliferation and extracellular-matrix accumulation in the development of pulmonary hypertension and remodeling, this study determined the effects of different doses of adrenomedullin (ADM) and adrenotensin (ADT) on PASMC proliferation and collagen synthesis. The objective was to investigate whether extracellular signal-regulated kinase (ERK1/2) signaling was involved in ADM- and ADT-stimulated proliferation of PASMCs in 4-week-old male Wistar rats (body weight: 100-150 g, n=10). The proliferation of PASMCs was examined by 5-bromo-2-deoxyuridine incorporation. A cell growth curve was generated by the Cell Counting Kit-8 method. Expression of collagen I, collagen III, and phosphorylated ERK1/2 (p-ERK1/2) was evaluated by immunofluorescence. The effects of different concentrations of ADM and ADT on collagen I, collagen III, and p-ERK1/2 protein expression were determined by immunoblotting. We also investigated the effect of PD98059 inhibition on the expression of p-ERK1/2 protein by immunoblotting. ADM dose-dependently decreased cell proliferation, whereas ADT dose-dependently increased it; and ADM and ADT inhibited each other with respect to their effects on the proliferation of PASMCs. Consistent with these results, the expression of collagen I, collagen III, and p-ERK1/2 in rat PASMCs decreased after exposure to ADM but was upregulated after exposure to ADT. PD98059 significantly inhibited the downregulation by ADM and the upregulation by ADT of p-ERK1/2 expression. We conclude that ADM inhibited, and ADT stimulated, ERK1/2 signaling in rat PASMCs to regulate cell proliferation and collagen expression.

  10. Adrenomedullin and adrenotensin regulate collagen synthesis and proliferation in pulmonary arterial smooth muscle cells

    International Nuclear Information System (INIS)

    To understand the pathophysiological mechanisms of pulmonary arterial smooth muscle cell (PASMC) proliferation and extracellular-matrix accumulation in the development of pulmonary hypertension and remodeling, this study determined the effects of different doses of adrenomedullin (ADM) and adrenotensin (ADT) on PASMC proliferation and collagen synthesis. The objective was to investigate whether extracellular signal-regulated kinase (ERK1/2) signaling was involved in ADM- and ADT-stimulated proliferation of PASMCs in 4-week-old male Wistar rats (body weight: 100-150 g, n=10). The proliferation of PASMCs was examined by 5-bromo-2-deoxyuridine incorporation. A cell growth curve was generated by the Cell Counting Kit-8 method. Expression of collagen I, collagen III, and phosphorylated ERK1/2 (p-ERK1/2) was evaluated by immunofluorescence. The effects of different concentrations of ADM and ADT on collagen I, collagen III, and p-ERK1/2 protein expression were determined by immunoblotting. We also investigated the effect of PD98059 inhibition on the expression of p-ERK1/2 protein by immunoblotting. ADM dose-dependently decreased cell proliferation, whereas ADT dose-dependently increased it; and ADM and ADT inhibited each other with respect to their effects on the proliferation of PASMCs. Consistent with these results, the expression of collagen I, collagen III, and p-ERK1/2 in rat PASMCs decreased after exposure to ADM but was upregulated after exposure to ADT. PD98059 significantly inhibited the downregulation by ADM and the upregulation by ADT of p-ERK1/2 expression. We conclude that ADM inhibited, and ADT stimulated, ERK1/2 signaling in rat PASMCs to regulate cell proliferation and collagen expression

  11. HDAC1 regulates the proliferation of radial glial cells in the developing Xenopus tectum.

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    Yi Tao

    Full Text Available In the developing central nervous system (CNS, progenitor cells differentiate into progeny to form functional neural circuits. Radial glial cells (RGs are a transient progenitor cell type that is present during neurogenesis. It is thought that a combination of neural trophic factors, neurotransmitters and electrical activity regulates the proliferation and differentiation of RGs. However, it is less clear how epigenetic modulation changes RG proliferation. We sought to explore the effect of histone deacetylase (HDAC activity on the proliferation of RGs in the visual optic tectum of Xenopus laevis. We found that the number of BrdU-labeled precursor cells along the ventricular layer of the tectum decrease developmentally from stage 46 to stage 49. The co-labeling of BrdU-positive cells with brain lipid-binding protein (BLBP, a radial glia marker, showed that the majority of BrdU-labeled cells along the tectal midline are RGs. BLBP-positive cells are also developmentally decreased with the maturation of the brain. Furthermore, HDAC1 expression is developmentally down-regulated in tectal cells, especially in the ventricular layer of the tectum. Pharmacological blockade of HDACs using Trichostatin A (TSA or Valproic acid (VPA decreased the number of BrdU-positive, BLBP-positive and co-labeling cells. Specific knockdown of HDAC1 by a morpholino (HDAC1-MO decreased the number of BrdU- and BLBP-labeled cells and increased the acetylation level of histone H4 at lysine 12 (H4K12. The visual deprivation-induced increase in BrdU- and BLBP-positive cells was blocked by HDAC1 knockdown at stage 49 tadpoles. These data demonstrate that HDAC1 regulates radial glia cell proliferation in the developing optical tectum of Xenopus laevis.

  12. Homeobox A7 increases cell proliferation by up-regulation of epidermal growth factor receptor expression in human granulosa cells

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    Yanase Toshihiko

    2010-06-01

    Full Text Available Abstract Background Homeobox (HOX genes encode transcription factors, which regulate cell proliferation, differentiation, adhesion, and migration. The deregulation of HOX genes is frequently associated with human reproductive system disorders. However, knowledge regarding the role of HOX genes in human granulosa cells is limited. Methods To determine the role of HOXA7 in the regulation and associated mechanisms of cell proliferation in human granulosa cells, HOXA7 and epidermal growth factor receptor (EGFR expressions were examined in primary granulosa cells (hGCs, an immortalized human granulosa cell line, SVOG, and a granulosa tumor cell line, KGN, by real-time PCR and Western blotting. To manipulate the expression of HOXA7, the HOXA7 specific siRNA was used to knockdown HOXA7 in KGN. Conversely, HOXA7 was overexpressed in SVOG by transfection with the pcDNA3.1-HOAX7 vector. Cell proliferation was measured by the MTT assay. Results Our results show that HOXA7 and EGFR were overexpressed in KGN cells compared to hGCs and SVOG cells. Knockdown of HOXA7 in KGN cells significantly decreased cell proliferation and EGFR expression. Overexpression of HOXA7 in SVOG cells significantly promoted cell growth and EGFR expression. Moreover, the EGF-induced KGN proliferation was abrogated, and the activation of downstream signaling was diminished when HOXA7 was knocked down. Overexpression of HOXA7 in SVOG cells had an opposite effect. Conclusions Our present study reveals a novel mechanistic role for HOXA7 in modulating granulosa cell proliferation via the regulation of EGFR. This finding contributes to the knowledge of the pro-proliferation effect of HOXA7 in granulosa cell growth and differentiation.

  13. Mast Cell-activated Bone Marrow Mesenchymal Stromal Cells Regulate Proliferation and Lineage Commitment of CD34+ Progenitor cells

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    Zoulfia eAllakhverdi

    2013-12-01

    Full Text Available Background: Shortly after allergen exposure, the number of bone marrow and circulating CD34+ progenitors increases. We aim to analyze the possible mechanism whereby the allergic reaction stimulates bone marrow to release these effector cells in increased numbers. We hypothesize that mast cells may play a predominant role in this process. Objective: To examine the effect of IgE-activated mast cells on bone marrow mesenchymal stromal cells which regulate proliferation and differentiation of CD34+ progenitors. Methods: Primary mast cells were derived from CD34+ precursors and activated with IgE/anti-IgE. Bone marrow mesenchymal stromal cells were co-cultured with CD34+ progenitor cells and stimulated with IL1/TNF or IgE/anti-IgE activated mast cells in Transwell system. Results: Bone marrow mesenchymal stromal cells produce low level of TSLP under steady state conditions, which is markedly increased by stimulation with proinflammatory cytokines IL-1 and TNF or IgE-activated mast cells. The latter also triggers BM-MSCs production of G-CSF, and GM-CSF while inhibiting SDF-1. Mast cell-activated mesenchymal stromal cells stimulate CD34+ cells to proliferate and to regulate their expression of early allergy-associated genes. Conclusion and Clinical Relevance: This in vitro study indicates that IgE-activated mast cells trigger bone marrow mesenchymal stromal cells to release TSLP and hematopoietic growth factors and to regulate the proliferation and lineage commitment of CD34+ precursor cells. The data predict that the effective inhibition of mast cells should impair mobilization and accumulation of allergic effector cells and thereby reduce the severity of allergic diseases.

  14. Adaptor protein LNK is a negative regulator of brain neural stem cell proliferation after stroke.

    Science.gov (United States)

    Ahlenius, Henrik; Devaraju, Karthikeyan; Monni, Emanuela; Oki, Koichi; Wattananit, Somsak; Darsalia, Vladimer; Iosif, Robert E; Torper, Olof; Wood, James C; Braun, Sebastian; Jagemann, Lucas; Nuber, Ulrike A; Englund, Elisabet; Jacobsen, Sten-Eirik W; Lindvall, Olle; Kokaia, Zaal

    2012-04-11

    Ischemic stroke causes transient increase of neural stem and progenitor cell (NSPC) proliferation in the subventricular zone (SVZ), and migration of newly formed neuroblasts toward the damaged area where they mature to striatal neurons. The molecular mechanisms regulating this plastic response, probably involved in structural reorganization and functional recovery, are poorly understood. The adaptor protein LNK suppresses hematopoietic stem cell self-renewal, but its presence and role in the brain are poorly understood. Here we demonstrate that LNK is expressed in NSPCs in the adult mouse and human SVZ. Lnk(-/-) mice exhibited increased NSPC proliferation after stroke, but not in intact brain or following status epilepticus. Deletion of Lnk caused increased NSPC proliferation while overexpression decreased mitotic activity of these cells in vitro. We found that Lnk expression after stroke increased in SVZ through the transcription factors STAT1/3. LNK attenuated insulin-like growth factor 1 signaling by inhibition of AKT phosphorylation, resulting in reduced NSPC proliferation. Our findings identify LNK as a stroke-specific, endogenous negative regulator of NSPC proliferation, and suggest that LNK signaling is a novel mechanism influencing plastic responses in postischemic brain. PMID:22496561

  15. Down-Regulated MAC30 Expression Inhibits Proliferation and Mobility of Human Gastric Cancer Cells

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    Xiao-Yan Xu

    2014-05-01

    Full Text Available Background: Gastric cancer is one of the most common cancers in the world. MAC30/Transmembrane protein 97 (TMEM97 is aberrantly up-regulated in many human carcinoma cells. However, the function of MAC30 in gastric carcinoma cells is not studied. Material and Methods: To investigate the function of MAC30 in gastric carcinoma, we used RNA silencing technology to knock down the expression of MAC30 in gastric cancer cells BGC-823 and AGS. Real-time quantitative PCR and Western blot were used to analyze the mRNA level and the related protein expression. The localization of MAC30 and lamellipodia was observed by immunofluorescence. The biological phenotypes of gastric cells were examined by cell proliferation assay, cell cycle analysis, apoptosis assay, cell migration and invasion assay. Results: We found that down-regulation of MAC30 expression efficiently inhibited the proliferation of gastric cancer cells. Furthermore, the mobility of gastric cancer cells was also inhibited by down-regulation of MAC30. Moreover, we found that MAC30 knockdown inhibited AKT phosphorylation and reduced the expression of cyclinB1 and WAVE2. Conclusion: To our knowledge, this is the first report investigating the effect of MAC30 on growth, cell cycle, migration, and invasion in gastric carcinoma cells via suppressing AKT signaling pathway. MAC30 may be a potential therapeutic target for treatment of gastric carcinoma.

  16. Mechanically stimulated bone cells secrete paracrine factors that regulate osteoprogenitor recruitment, proliferation, and differentiation

    International Nuclear Information System (INIS)

    Bone formation requires the recruitment, proliferation and osteogenic differentiation of mesenchymal progenitors. A potent stimulus driving this process is mechanical loading, yet the signalling mechanisms underpinning this are incompletely understood. The objective of this study was to investigate the role of the mechanically-stimulated osteocyte and osteoblast secretome in coordinating progenitor contributions to bone formation. Initially osteocytes (MLO-Y4) and osteoblasts (MC3T3) were mechanically stimulated for 24hrs and secreted factors within the conditioned media were collected and used to evaluate mesenchymal stem cell (MSC) and osteoblast recruitment, proliferation and osteogenesis. Paracrine factors secreted by mechanically stimulated osteocytes significantly enhanced MSC migration, proliferation and osteogenesis and furthermore significantly increased osteoblast migration and proliferation when compared to factors secreted by statically cultured osteocytes. Secondly, paracrine factors secreted by mechanically stimulated osteoblasts significantly enhanced MSC migration but surprisingly, in contrast to the osteocyte secretome, inhibited MSC proliferation when compared to factors secreted by statically cultured osteoblasts. A similar trend was observed in osteoblasts. This study provides new information on mechanically driven signalling mechanisms in bone and highlights a contrasting secretome between cells at different stages in the bone lineage, furthering our understanding of loading-induced bone formation and indirect biophysical regulation of osteoprogenitors. - Highlights: • Physically stimulated osteocytes secrete factors that regulate osteoprogenitors. • These factors enhance recruitment, proliferation and osteogenic differentiation. • Physically stimulated osteoblasts secrete factors that also regulate progenitors. • These factors enhance recruitment but inhibit proliferation of osteoprogenitors. • This study highlights a contrasting

  17. Mechanically stimulated bone cells secrete paracrine factors that regulate osteoprogenitor recruitment, proliferation, and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Robert T. [Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland (Ireland); Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Advanced Materials and BioEngineering Research Centre (AMBER), Trinity College Dublin & Royal College of Surgeons in Ireland (Ireland); Dept. of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick (Ireland); O' Brien, Fergal J. [Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland (Ireland); Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Advanced Materials and BioEngineering Research Centre (AMBER), Trinity College Dublin & Royal College of Surgeons in Ireland (Ireland); Hoey, David A., E-mail: david.hoey@ul.ie [Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Dept. of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick (Ireland); The Centre for Applied Biomedical Engineering Research, University of Limerick (Ireland); Materials & Surface Science Institute, University of Limerick (Ireland)

    2015-03-27

    Bone formation requires the recruitment, proliferation and osteogenic differentiation of mesenchymal progenitors. A potent stimulus driving this process is mechanical loading, yet the signalling mechanisms underpinning this are incompletely understood. The objective of this study was to investigate the role of the mechanically-stimulated osteocyte and osteoblast secretome in coordinating progenitor contributions to bone formation. Initially osteocytes (MLO-Y4) and osteoblasts (MC3T3) were mechanically stimulated for 24hrs and secreted factors within the conditioned media were collected and used to evaluate mesenchymal stem cell (MSC) and osteoblast recruitment, proliferation and osteogenesis. Paracrine factors secreted by mechanically stimulated osteocytes significantly enhanced MSC migration, proliferation and osteogenesis and furthermore significantly increased osteoblast migration and proliferation when compared to factors secreted by statically cultured osteocytes. Secondly, paracrine factors secreted by mechanically stimulated osteoblasts significantly enhanced MSC migration but surprisingly, in contrast to the osteocyte secretome, inhibited MSC proliferation when compared to factors secreted by statically cultured osteoblasts. A similar trend was observed in osteoblasts. This study provides new information on mechanically driven signalling mechanisms in bone and highlights a contrasting secretome between cells at different stages in the bone lineage, furthering our understanding of loading-induced bone formation and indirect biophysical regulation of osteoprogenitors. - Highlights: • Physically stimulated osteocytes secrete factors that regulate osteoprogenitors. • These factors enhance recruitment, proliferation and osteogenic differentiation. • Physically stimulated osteoblasts secrete factors that also regulate progenitors. • These factors enhance recruitment but inhibit proliferation of osteoprogenitors. • This study highlights a contrasting

  18. Nitric Oxide Prevents Mouse Embryonic Stem Cell Differentiation Through Regulation of Gene Expression, Cell Signaling, and Control of Cell Proliferation.

    Science.gov (United States)

    Tapia-Limonchi, Rafael; Cahuana, Gladys M; Caballano-Infantes, Estefania; Salguero-Aranda, Carmen; Beltran-Povea, Amparo; Hitos, Ana B; Hmadcha, Abdelkrim; Martin, Franz; Soria, Bernat; Bedoya, Francisco J; Tejedo, Juan R

    2016-09-01

    Nitric oxide (NO) delays mouse embryonic stem cell (mESC) differentiation by regulating genes linked to pluripotency and differentiation. Nevertheless, no profound study has been conducted on cell differentiation regulation by this molecule through signaling on essential biological functions. We sought to demonstrate that NO positively regulates the pluripotency transcriptional core, enforcing changes in the chromatin structure, in addition to regulating cell proliferation, and signaling pathways with key roles in stemness. Culturing mESCs with 2 μM of the NO donor diethylenetriamine/NO (DETA/NO) in the absence of leukemia inhibitory factor (LIF) induced significant changes in the expression of 16 genes of the pluripotency transcriptional core. Furthermore, treatment with DETA/NO resulted in a high occupancy of activating H3K4me3 at the Oct4 and Nanog promoters and repressive H3K9me3 and H3k27me3 at the Brachyury promoter. Additionally, the activation of signaling pathways involved in pluripotency, such as Gsk3-β/β-catenin, was observed, in addition to activation of PI3 K/Akt, which is consistent with the protection of mESCs from cell death. Finally, a decrease in cell proliferation coincides with cell cycle arrest in G2/M. Our results provide novel insights into NO-mediated gene regulation and cell proliferation and suggest that NO is necessary but not sufficient for the maintenance of pluripotency and the prevention of cell differentiation. J. Cell. Biochem. 117: 2078-2088, 2016. © 2016 Wiley Periodicals, Inc. PMID:26853909

  19. MicroRNA-765 regulates neural stem cell proliferation and differentiation by modulating Hes1 expression

    Science.gov (United States)

    Li, Siou; Zhao, Weina; Xu, Qing; Yu, Yang; Yin, Changhao

    2016-01-01

    Neural stem cells (NSCs) are multipotent, self-renewing and undifferentiated cells that have the ability to differentiate to both glial and neuronal lineages. miRNAs act a key role in regulating neuronal fate and self-renewal of NSCs. In this study, we found that ectopic expression of miR-765 promoted NSCs proliferation. Moreover, miR-765 overexpression increased the ki-67 and β-tubulin-III expression inNSCs. Overexpression of miR-765 inhibited the expression of GFAP in NSCs. Furthermore, Hes1 was identified as a direct target gene of miR-765 in NSCs. Overexpression of Hes1 decreased miR-765-induced proliferation of NSCs and inhibited NSCs differentiation to neurons in miR-765-treated NSCs. These results demonstrated that miR-765 acted a crucial role in NSCs differentiation and proliferation by inhibiting Hes1 expression. PMID:27508032

  20. The hippo pathway promotes Notch signaling in regulation of cell differentiation, proliferation, and oocyte polarity.

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    Jianzhong Yu

    Full Text Available Specification of the anterior-posterior axis in Drosophila oocytes requires proper communication between the germ-line cells and the somatically derived follicular epithelial cells. Multiple signaling pathways, including Notch, contribute to oocyte polarity formation by controlling the temporal and spatial pattern of follicle cell differentiation and proliferation. Here we show that the newly identified Hippo tumor-suppressor pathway plays a crucial role in the posterior follicle cells in the regulation of oocyte polarity. Disruption of the Hippo pathway, including major components Hippo, Salvador, and Warts, results in aberrant follicle-cell differentiation and proliferation and dramatic disruption of the oocyte anterior-posterior axis. These phenotypes are related to defective Notch signaling in follicle cells, because misexpression of a constitutively active form of Notch alleviates the oocyte polarity defects. We also find that follicle cells defective in Hippo signaling accumulate the Notch receptor and display defects in endocytosis markers. Our findings suggest that the interaction between Hippo and classic developmental pathways such as Notch is critical to spatial and temporal regulation of differentiation and proliferation and is essential for development of the body axes in Drosophila.

  1. Regulation of cell proliferation and migration in glioblastoma: New therapeutic approach

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    Yangjin eKim

    2013-03-01

    Full Text Available Glioblastoma is the aggressive brain cancer with the poor survival rate. A microRNA, miR-451, and its downstream molecules, CAB39/LKB1/STRAD/AMPK, are known to play a critical role in regulating a biochemical balance between rapid proliferation and invasion in the presence of metabolic stress in microenvironment. We develop a novel multi-scale mathematical model where cell migration and proliferation are controlled through a core intracellular control system (miR-451-AMPK complex in response to glucose availability and physical constraints in the microenvironment. Tumor cells are modeled individually and proliferation and migration of those cells are regulated by the intracellular dynamics and reaction-di□usion equations of concentrations of glucose, chemoattractant, extracellular matrix, and MMPs. The model predicts that invasion patterns and rapid growth of tumor cells after conventional surgery depend onbiophysical properties of cells, dynamics of the core control system, and microenvironment as well as glucose injection methods. We developed a new type of therapeutic approaches: effective injection of chemoattractant for bring invasive cells back to the surgical site after initial surgery, followed by glucose injection at the same location. The model suggests that a good combination of chemoattractant and glucose injection at appropriate time frames may lead to an effective therapeutic strategy of eradicating tumor cells.

  2. Distinct roles of Shh and Fgf signaling in regulating cell proliferation during zebrafish pectoral fin development

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    Neumann Carl J

    2008-09-01

    Full Text Available Abstract Background Cell proliferation in multicellular organisms must be coordinated with pattern formation. The major signaling pathways directing pattern formation in the vertebrate limb are well characterized, and we have therefore chosen this organ to examine the interaction between proliferation and patterning. Two important signals for limb development are members of the Hedgehog (Hh and Fibroblast Growth Factor (Fgf families of secreted signaling proteins. Sonic hedgehog (Shh directs pattern formation along the anterior/posterior axis of the limb, whereas several Fgfs in combination direct pattern formation along the proximal/distal axis of the limb. Results We used the genetic and pharmacological amenability of the zebrafish model system to dissect the relative importance of Shh and Fgf signaling in regulating proliferation during development of the pectoral fin buds. In zebrafish mutants disrupting the shh gene, proliferation in the pectoral fin buds is initially normal, but later is strongly reduced. Correlating with this reduction, Fgf signaling is normal at early stages, but is later lost in shh mutants. Furthermore, pharmacological inhibition of Hh signaling for short periods has little effect on either Fgf signaling, or on expression of G1- and S-phase cell-cycle genes, whereas long periods of inhibition lead to the downregulation of both. In contrast, even short periods of pharmacological inhibition of Fgf signaling lead to strong disruption of proliferation in the fin buds, without affecting Shh signaling. To directly test the ability of Fgf signaling to regulate proliferation in the absence of Shh signaling, we implanted beads soaked with Fgf protein into shh mutant fin buds. We find that Fgf-soaked beads rescue proliferation in the pectoral find buds of shh mutants, indicating that Fgf signaling is sufficient to direct proliferation in zebrafish fin buds in the absence of Shh. Conclusion Previous studies have shown that both

  3. The ADP-ribose polymerase Tankyrase regulates adult intestinal stem cell proliferation during homeostasis in Drosophila.

    Science.gov (United States)

    Wang, Zhenghan; Tian, Ai; Benchabane, Hassina; Tacchelly-Benites, Ofelia; Yang, Eungi; Nojima, Hisashi; Ahmed, Yashi

    2016-05-15

    Wnt/β-catenin signaling controls intestinal stem cell (ISC) proliferation, and is aberrantly activated in colorectal cancer. Inhibitors of the ADP-ribose polymerase Tankyrase (Tnks) have become lead therapeutic candidates for Wnt-driven cancers, following the recent discovery that Tnks targets Axin, a negative regulator of Wnt signaling, for proteolysis. Initial reports indicated that Tnks is important for Wnt pathway activation in cultured human cell lines. However, the requirement for Tnks in physiological settings has been less clear, as subsequent studies in mice, fish and flies suggested that Tnks was either entirely dispensable for Wnt-dependent processes in vivo, or alternatively, had tissue-specific roles. Here, using null alleles, we demonstrate that the regulation of Axin by the highly conserved Drosophila Tnks homolog is essential for the control of ISC proliferation. Furthermore, in the adult intestine, where activity of the Wingless pathway is graded and peaks at each compartmental boundary, Tnks is dispensable for signaling in regions where pathway activity is high, but essential where pathway activity is relatively low. Finally, as observed previously for Wingless pathway components, Tnks activity in absorptive enterocytes controls the proliferation of neighboring ISCs non-autonomously by regulating JAK/STAT signaling. These findings reveal the requirement for Tnks in the control of ISC proliferation and suggest an essential role in the amplification of Wnt signaling, with relevance for development, homeostasis and cancer. PMID:27190037

  4. Protein phosphatase 2A Cα regulates proliferation, migration, and metastasis of osteosarcoma cells.

    Science.gov (United States)

    Yang, Di; Okamura, Hirohiko; Morimoto, Hiroyuki; Teramachi, Jumpei; Haneji, Tatsuji

    2016-10-01

    Osteosarcoma is the most frequent primary bone tumor. Serine/threonine protein phosphatase 2A (PP2A) participates in regulating many important physiological processes, such as cell cycle, growth, apoptosis, and signal transduction. In this study, we examined the expression and function of PP2A Cα in osteosarcoma cells. PP2A Cα expression was expected to be higher in malignant osteosarcoma tissues. PP2A Cα expression level and PP2A activity was higher in malignant osteosarcoma LM8 cells compared with that in primary osteoblasts and in the osteoblast-like cell line MC3T3-E1. Okadaic acid, an inhibitor of PP2A, reduced cell viability and induced apoptosis in LM8 cells. PP2A Cα-knockdown LM8 cells (shPP2A) exhibited less striking filopodial and lamellipodial structures than that in original LM8 cells. Focal adhesion kinase phosphorylation and NF-κB activity decreased in shPP2A-treated cells. Sensitivity to serum deprivation-induced apoptosis increased in shPP2A-treated cells, accompanied by a lower expression level of anti-apoptotic BCL-2 in these cells. Reduction of PP2A Cα resulted in a decrease in the migration ability of LM8 cells in vitro. Reduction in PP2A Cα levels in vivo suppressed proliferation and metastasis in LM8 cells. PP2A Cα expression was also higher in human osteosarcoma MG63 and SaOS-2 cells than that in primary osteoblasts and MC3T3-E1 cells, and reduction in PP2A Cα levels suppressed the cell proliferation rate and migration ability of MG63 cells. These results indicate that PP2A Cα has a critical role in the proliferation and metastasis of osteosarcoma cells; therefore, its inhibition could potentially suppress the malignancy of osteosarcoma cells. PMID:27617401

  5. Proprotein convertase furin regulates apoptosis and proliferation of granulosa cells in the rat ovary.

    Directory of Open Access Journals (Sweden)

    Xiaokui Yang

    Full Text Available Folliculogenesis is tightly controlled by a series of hormones, growth factors and cytokines, many of which are secreted as proproteins and require processing by proteases before becoming functional. Furin is a member of the subtilisin-like proteases that activate large numbers of proprotein substrates and is ubiquitously expressed and implicated in many physiological and pathological processes. However, the precise role of furin during folliculogenesis has not been thoroughly investigated. The goal of the present work is to identify the role of furin in the development of granulosa cells during folliculogenesis, using immunohistochemistry, RT-PCR, Western blot and functional studies in primary cultured rat granulosa cells. Our results demonstrate that furin is highly expressed in granulosa cells and oocytes of the ovary with very limited expression in other ovarian cells such as the epithelial, stromal or theca cells. Furin siRNA significantly increases apoptosis of the granulosa cells from large antral/preovulatory follicles, in part via downregulation of the anti-apoptotic proteins, XIAP and p-AKT. On the contrary, furin siRNA markedly decreases proliferation of granulosa cells based on the downregulation of proliferation cell nuclear antigen (PCNA. Taken together, these data suggest that furin may play an important role in regulating apoptosis and proliferation of granulosa cells.

  6. Annexin A6 regulates interleukin-2-mediated T-cell proliferation.

    Science.gov (United States)

    Cornely, Rhea; Pollock, Abigail H; Rentero, Carles; Norris, Sarah E; Alvarez-Guaita, Anna; Grewal, Thomas; Mitchell, Todd; Enrich, Carlos; Moss, Stephen E; Parton, Robert G; Rossy, Jérémie; Gaus, Katharina

    2016-07-01

    Annexin A6 (AnxA6) has been implicated in cell signalling by contributing to the organisation of the plasma membrane. Here we examined whether AnxA6 regulates signalling and proliferation in T cells. We used a contact hypersensitivity model to immune challenge wild-type (WT) and AnxA6(-/-) mice and found that the in vivo proliferation of CD4(+) T cells, but not CD8(+) T cells, was impaired in AnxA6(-/-) relative to WT mice. However, T-cell migration and signalling through the T-cell receptor ex vivo was similar between T cells isolated from AnxA6(-/-) and WT mice. In contrast, interleukin-2 (IL-2) signalling was reduced in AnxA6(-/-) compared with WT T cells. Further, AnxA6-deficient T cells had reduced membrane order and cholesterol levels. Taken together, our data suggest that AnxA6 regulates IL-2 homeostasis and sensitivity in T cells by sustaining a lipid raft-like membrane environment. PMID:26853809

  7. ZEB2 mediates multiple pathways regulating cell proliferation, migration, invasion, and apoptosis in glioma.

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    Songtao Qi

    Full Text Available BACKGROUND: The aim of the present study was to analyze the expression of Zinc finger E-box Binding homeobox 2 (ZEB2 in glioma and to explore the molecular mechanisms of ZEB2 that regulate cell proliferation, migration, invasion, and apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: Expression of ZEB2 in 90 clinicopathologically characterized glioma patients was analyzed by immunohistochemistry. Furthermore, siRNA targeting ZEB2 was transfected into U251 and U87 glioma cell lines in vitro and proliferation, migration, invasion, and apoptosis were examined separately by MTT assay, Transwell chamber assay, flow cytometry, and western blot. RESULTS: The expression level of ZEB2 protein was significantly increased in glioma tissues compared to normal brain tissues (P<0.001. In addition, high levels of ZEB2 protein were positively correlated with pathology grade classification (P = 0.024 of glioma patients. Knockdown of ZEB2 by siRNA suppressed cell proliferation, migration and invasion, as well as induced cell apoptosis in glioma cells. Furthermore, ZEB2 downregulation was accompanied by decreased expression of CDK4/6, Cyclin D1, Cyclin E, E2F1, and c-myc, while p15 and p21 were upregulated. Lowered expression of ZEB2 enhanced E-cadherin levels but also inhibited β-Catenin, Vimentin, N-cadherin, and Snail expression. Several apoptosis-related regulators such as Caspase-3, Caspase-6, Caspase-9, and Cleaved-PARP were activated while PARP was inhibited after ZEB2 siRNA treatment. CONCLUSION: Overexpression of ZEB2 is an unfavorable factor that may facilitate glioma progression. Knockdown ZEB2 expression by siRNA suppressed cell proliferation, migration, invasion and promoted cell apoptosis in glioma cells.

  8. Mechanically stimulated bone cells secrete paracrine factors that regulate osteoprogenitor recruitment, proliferation, and differentiation.

    Science.gov (United States)

    Brady, Robert T; O'Brien, Fergal J; Hoey, David A

    2015-03-27

    Bone formation requires the recruitment, proliferation and osteogenic differentiation of mesenchymal progenitors. A potent stimulus driving this process is mechanical loading, yet the signalling mechanisms underpinning this are incompletely understood. The objective of this study was to investigate the role of the mechanically-stimulated osteocyte and osteoblast secretome in coordinating progenitor contributions to bone formation. Initially osteocytes (MLO-Y4) and osteoblasts (MC3T3) were mechanically stimulated for 24 hrs and secreted factors within the conditioned media were collected and used to evaluate mesenchymal stem cell (MSC) and osteoblast recruitment, proliferation and osteogenesis. Paracrine factors secreted by mechanically stimulated osteocytes significantly enhanced MSC migration, proliferation and osteogenesis and furthermore significantly increased osteoblast migration and proliferation when compared to factors secreted by statically cultured osteocytes. Secondly, paracrine factors secreted by mechanically stimulated osteoblasts significantly enhanced MSC migration but surprisingly, in contrast to the osteocyte secretome, inhibited MSC proliferation when compared to factors secreted by statically cultured osteoblasts. A similar trend was observed in osteoblasts. This study provides new information on mechanically driven signalling mechanisms in bone and highlights a contrasting secretome between cells at different stages in the bone lineage, furthering our understanding of loading-induced bone formation and indirect biophysical regulation of osteoprogenitors. PMID:25721667

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

    Science.gov (United States)

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

    2016-04-01

    In the adult brain, neural stem cells from the subgranular zone (SGZ) of the hippocampus and the subventricular zone (SVZ) of the cortex progress through the following five developmental stages: radial glia-like cells, neural progenitor cells, neuroblasts, immature neurons, and mature neurons. These developmental stages are linked to both neuronal microenvironments and energy metabolism. Neurogenesis is restricted and has been demonstrated to arise from tissue microenvironments. We determined that magnesium, a key nutrient in cellular energy metabolism, affects neural stem cell (NSC) proliferation in cells derived from the embryonic hippocampus by influencing mitochondrial function. Densities of proliferating cells and NSCs both showed their highest values at 0.8 mM [Mg(2+) ]o , whereas lower proliferation rates were observed at 0.4 and 1.4 mM [Mg(2+) ]o . The numbers and sizes of the neurospheres reached the maximum at 0.8 mM [Mg(2+) ]o and were weaker under both low (0.4 mM) and high (1.4 mM) concentrations of magnesium. In vitro experimental evidence demonstrates that extracellular magnesium regulates the number of cultured hippocampal NSCs, affecting both magnesium homeostasis and mitochondrial function. Our findings indicate that the effect of [Mg(2+) ]o on NSC proliferation may lie downstream of alterations in mitochondrial function because mitochondrial membrane potential was highest in the NSCs in the moderate [Mg(2+) ]o (0.8 mM) group and lower in both the low (0.4 mM) and high (1.4 mM) [Mg(2+) ]o groups. Overall, these findings demonstrate a new function for magnesium in the brain in the regulation of hippocampal neural stem cells: affecting their cellular energy metabolism. PMID:26634890

  10. Defective CFTR-regulated granulosa cell proliferation in polycystic ovarian syndrome.

    Science.gov (United States)

    Chen, Hui; Guo, Jing Hui; Zhang, Xiao Hu; Chan, Hsiao Chang

    2015-05-01

    Polycystic ovarian syndrome (PCOS) is one of the most frequent causes of female infertility, featured by abnormal hormone profile, chronic oligo/anovulation, and presence of multiple cystic follicles in the ovary. However, the mechanism underlying the abnormal folliculogenesis remains obscure. We have previously demonstrated that CFTR, a cAMP-dependent Cl(-) and HCO3 (-) conducting anion channel, is expressed in the granulosa cells and its expression is downregulated in PCOS rat models and human patients. In this study, we aimed to investigate the possible involvement of downregulation of CFTR in the impaired follicle development in PCOS using two rat PCOS models and primary culture of granulosa cells. Our results indicated that the downregulation of CFTR in the cystic follicles was accompanied by reduced expression of proliferating cell nuclear antigen (PCNA), in rat PCOS models. In addition, knockdown or inhibition of CFTR in granulosa cell culture resulted in reduced cell viability and downregulation of PCNA. We further demonstrated that CFTR regulated both basal and FSH-stimulated granulosa cell proliferation through the HCO3 (-)/sAC/PKA pathway leading to ERK phosphorylation and its downstream target cyclin D2 (Ccnd2) upregulation. Reduced ERK phosphorylation and CCND2 were found in ovaries of rat PCOS model compared with the control. This study suggests that CFTR is required for normal follicle development and that its downregulation in PCOS may inhibit granulosa cell proliferation, resulting in abnormal follicle development in PCOS.

  11. Cell Proliferation in Neuroblastoma

    Directory of Open Access Journals (Sweden)

    Laura L. Stafman

    2016-01-01

    Full Text Available 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.

  12. hCLP46 regulates U937 cell proliferation via Notch signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Wenzhan; Du, Jie; Chu, Qiaoyun [College of Life Science, Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Wang, Youxin [School of Public Health and Family Medicine, Capital Medical University, Beijing 100069 (China); Liu, Lixin [College of Life Science, Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Song, Manshu [School of Public Health and Family Medicine, Capital Medical University, Beijing 100069 (China); Wang, Wei, E-mail: wei6014@yahoo.com [College of Life Science, Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); School of Public Health and Family Medicine, Capital Medical University, Beijing 100069 (China)

    2011-04-29

    Highlights: {yields} Knock down of hCLP46 by RNAi impairs mammalian Notch signaling. {yields} hCLP46 affects neither cell surface Notch1 expression nor ligand-receptor binding. {yields} Knock down of hCLP46 inhibits U937 cell-growth by up-regulation of CDKN1B. -- Abstract: Human CAP10-like protein 46 kDa (hCLP46) is the homolog of Rumi, which is the first identified protein O-glucosyltransferase that modifies Notch receptor in Drosophila. Dysregulation of hCLP46 occurs in many hematologic diseases, but the role of hCLP46 remains unclear. Knockdown of hCLP46 by RNA interference resulted in decreased protein levels of endogenous Notch1, Notch intracellular domain (NICD) and Notch target gene Hes-1, suggesting the impairment of the Notch signaling. However, neither cell surface Notch expression nor ligand binding activities were affected. In addition, down-regulated expression of hCLP46 inhibited the proliferation of U937 cells, which was correlated with increased cyclin-dependent kinase inhibitor (CDKI) CDKN1B (p27) and decreased phosphorylation of retinoblastoma (RB) protein. We showed that lack of hCLP46 results in impaired ligand induced Notch activation in mammalian cell, and hCLP46 regulates the proliferation of U937 cell through CDKI-RB signaling pathway, which may be important for the pathogenesis of leukemia.

  13. Syndecan-1 responsive microRNA-126 and 149 regulate cell proliferation in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Tomomi; Shimada, Keiji [Department of Pathology, Nara Medical University School of Medicine, Nara (Japan); Tatsumi, Yoshihiro [Department of Pathology, Nara Medical University School of Medicine, Nara (Japan); Department of Urology, Nara Medical University School of Medicine, Nara (Japan); Fujimoto, Kiyohide [Department of Urology, Nara Medical University School of Medicine, Nara (Japan); Konishi, Noboru, E-mail: nkonishi@naramed-u.ac.jp [Department of Pathology, Nara Medical University School of Medicine, Nara (Japan)

    2015-01-02

    Highlights: • Syndecan-1 is highly expressed in androgen independent prostate cancer cells, PC3. • Syndecan-1 regulates the expression of miR-126 and -149 in prostate cancer cells. • MiR-126 and 149 control cell growth via p21 induction and senescence mechanism. • MiR-126 and 149 promote cell proliferation by suppressing SOX2, NANOG, and Oct4. - Abstract: MicroRNAs (miRNAs) are short (19–24 nt), low molecular weight RNAs that play important roles in the regulation of target genes associated with cell proliferation, differentiation, and development, by binding to the 3′-untranslated region of the target mRNAs. In this study, we examined the expression of miRNA-126 (miR-126) and miR-149 in prostate cancer, and investigated the molecular mechanisms by which they affect syndecan-1 in prostate cancer. Functional analysis of miR-126 and miR-149 was conducted in the prostate cancer cell lines, PC3, Du145, and LNCaP. The expression levels of SOX2, NANOG, Oct4, miR-126 and miR-149 were evaluated by quantitative RT-PCR. After silencing syndecan-1, miR-126, and/or miR-149 in the PC3 cells, cell proliferation, senescence, and p21 induction were assessed using the MTS assay, senescence-associated β-galactosidase (SA-β-Gal) assay, and immunocytochemistry, respectively. Compared to the Du145 and LNCaP cells, PC3 cells exhibited higher expression of syndecan-1. When syndecan-1 was silenced, the PC3 cells showed reduced expression of miR-126 and miR-149 most effectively. Suppression of miR-126 and/or miR-149 significantly inhibited cell growth via p21 induction and subsequently, induced senescence. The mRNA expression levels of SOX2, NANOG, and Oct4 were significantly increased in response to the silencing of miR-126 and/or miR-149. Our results suggest that miR-126 and miR-149 are associated with the expression of syndecan-1 in prostate cancer cells. These miRNAs promote cell proliferation by suppressing SOX2, NANOG, and Oct4. The regulation of these factors by mi

  14. Tudor-SN Regulates Milk Synthesis and Proliferation of Bovine Mammary Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Jinxia Ao

    2015-12-01

    Full Text Available Tudor staphylococcal nuclease (Tudor-SN is a highly conserved and ubiquitously expressed multifunctional protein, related to multiple and diverse cell type- and species-specific cellular processes. Studies have shown that Tudor-SN is mainly expressed in secretory cells, however knowledge of its role is limited. In our previous work, we found that the protein level of Tudor-SN was upregulated in the nucleus of bovine mammary epithelial cells (BMEC. In this study, we assessed the role of Tudor-SN in milk synthesis and cell proliferation of BMEC. We exploited gene overexpression and silencing methods, and found that Tudor-SN positively regulates milk synthesis and proliferation via Stat5a activation. Both amino acids (methionine and estrogen triggered NFκB1 to bind to the gene promoters of Tudor-SN and Stat5a, and this enhanced the protein level and nuclear localization of Tudor-SN and p-Stat5a. Taken together, these results suggest the key role of Tudor-SN in the transcriptional regulation of milk synthesis and proliferation of BMEC under the stimulation of amino acids and hormones.

  15. Role of membrane potential in the regulation of cell proliferation and differentiation.

    Science.gov (United States)

    Sundelacruz, Sarah; Levin, Michael; Kaplan, David L

    2009-09-01

    Biophysical signaling, an integral regulator of long-term cell behavior in both excitable and non-excitable cell types, offers enormous potential for modulation of important cell functions. Of particular interest to current regenerative medicine efforts, we review several examples that support the functional role of transmembrane potential (V(mem)) in the regulation of proliferation and differentiation. Interestingly, distinct V(mem) controls are found in many cancer cell and precursor cell systems, which are known for their proliferative and differentiation capacities, respectively. Collectively, the data demonstrate that bioelectric properties can serve as markers for cell characterization and can control cell mitotic activity, cell cycle progression, and differentiation. The ability to control cell functions by modulating bioelectric properties such as V(mem) would be an invaluable tool for directing stem cell behavior toward therapeutic goals. Biophysical properties of stem cells have only recently begun to be studied and are thus in need of further characterization. Understanding the molecular and mechanistic basis of biophysical regulation will point the way toward novel ways to rationally direct cell functions, allowing us to capitalize upon the potential of biophysical signaling for regenerative medicine and tissue engineering. PMID:19562527

  16. Cell proliferation, apoptosis and the related regulators p27, p53 expression in hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Zhao Jing; Ke-Jun Nan; Mei-Long Hu

    2005-01-01

    AIM: To investigate the expression of cell apoptosis,proliferation and the related regulators p27, p53 in hepatocellular carcinoma (HCC).METHODS: The expression of p27, p53, proliferating cell nuclear antigen (PCNA) and apoptosis in 47 HCC specimens and 42 surrounding non-cancerous tissues were detected by the immunohistochemistry and terminal deoxy-nudeotidyl transferase-mediated nick end labeling (TUNEL) technique.Meanwhile, the clinical significance of them was analyzed combining with the clinicopathological factors and followup data.RESULTS: (1) The average proliferating index and apoptotic index in HCC were significantly higher than that in adjacent liver tissues. The proliferating index was associated with extrahepatic metastasis. The apoptotic index was significantly lower in TNM stage Ⅰ-Ⅱ than in stage Ⅲ-Ⅳ. The proliferating index of groups with p53-/p27+ was significantly lower than that in group with p53+/p27- (P = 0.030); (2) The level of p27 in the cytoplasmic fraction was higher in non-tumoral liver tissues and was associated with clinical stage; (3) Survival analysis showed advanced stage (P = 0.031) and with extrahepatic metastasis (P = 0.045) was significantly associated with shorter survival. In addition, the prognosis of patients with p53-/p27+ was longer than that of patients with p53+/p27- (P = 0.0356).CONCLUSION: The p53 mutation and decreased p27 expression might be involved in the imbalance of proliferation and apoptosis in HCC. Cytoplasmic displacement might lead to the inactivation of p27 protein in HCC cells and acts early during carcinogenesis of HCC. The combined examination of p27, and p53 expression allows reliable estimation of prognosis for patients with primary hepatic carcinoma.

  17. Human gastric mucins differently regulate Helicobacter pylori proliferation, gene expression and interactions with host cells.

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    Emma C Skoog

    Full Text Available Helicobacter pylori colonizes the mucus niche of the gastric mucosa and is a risk factor for gastritis, ulcers and cancer. The main components of the mucus layer are heavily glycosylated mucins, to which H. pylori can adhere. Mucin glycosylation differs between individuals and changes during disease. Here we have examined the H. pylori response to purified mucins from a range of tumor and normal human gastric tissue samples. Our results demonstrate that mucins from different individuals differ in how they modulate both proliferation and gene expression of H. pylori. The mucin effect on proliferation varied significantly between samples, and ranged from stimulatory to inhibitory, depending on the type of mucins and the ability of the mucins to bind to H. pylori. Tumor-derived mucins and mucins from the surface mucosa had potential to stimulate proliferation, while gland-derived mucins tended to inhibit proliferation and mucins from healthy uninfected individuals showed little effect. Artificial glycoconjugates containing H. pylori ligands also modulated H. pylori proliferation, albeit to a lesser degree than human mucins. Expression of genes important for the pathogenicity of H. pylori (babA, sabA, cagA, flaA and ureA appeared co-regulated in response to mucins. The addition of mucins to co-cultures of H. pylori and gastric epithelial cells protected the viability of the cells and modulated the cytokine production in a manner that differed between individuals, was partially dependent of adhesion of H. pylori to the gastric cells, but also revealed that other mucin factors in addition to adhesion are important for H. pylori-induced host signaling. The combined data reveal host-specific effects on proliferation, gene expression and virulence of H. pylori due to the gastric mucin environment, demonstrating a dynamic interplay between the bacterium and its host.

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

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    Wang, Guang; Li, Yan; Wang, Xiao-yu [Key Laboratory for Regenerative Medicine of The Ministry of Education, Department of Histology and Embryology, School of Medicine, Jinan University, Guangzhou 510632 (China); Han, Zhe [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510224 (China); Chuai, Manli [College of Life Sciences Biocentre, University of Dundee, Dundee DD1 5EH (United Kingdom); Wang, Li-jing [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510224 (China); Ho Lee, Kenneth Ka [Stem Cell and Regeneration Thematic Research Programme, School of Biomedical Sciences, Chinese University of Hong Kong, Shatin (Hong Kong); Geng, Jian-guo, E-mail: jgeng@umich.edu [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510224 (China); Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI 48109 (United States); Yang, Xuesong, E-mail: yang_xuesong@126.com [Key Laboratory for Regenerative Medicine of The Ministry of Education, Department of Histology and Embryology, School of Medicine, Jinan University, Guangzhou 510632 (China)

    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

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

    International Nuclear Information System (INIS)

    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+ migrating neural crest cells (NCCs). In addition, Robo1 over-expression enhanced Pax7 expression in the dorsal neural tube and increased the number of Slug+ pre-migratory NCCs. Conversely, silencing Robo1 expression resulted in an enhanced Shh expression and more HNK-1+ migrating NCCs but reduced Pax7 expression and fewer Slug+ pre-migratory NCCs were observed. In conclusion, we propose that Slit/Robo1 signaling is involved in regulating neural tube development by tightly

  20. Ion channels involved in cell volume regulation: effects on migration, proliferation, and programmed cell death in non adherent EAT cells and adherent ELA cells.

    Science.gov (United States)

    Hoffmann, Else Kay

    2011-01-01

    This mini review outlines studies of cell volume regulation in two closely related mammalian cell lines: nonadherent Ehrlich ascites tumour cells (EATC) and adherent Ehrlich Lettre ascites (ELA) cells. Focus is on the regulatory volume decrease (RVD) that occurs after cell swelling, the volume regulatory ion channels involved, and the mechanisms (cellular signalling pathways) that regulate these channels. Finally, I shall also briefly review current investigations in these two cell lines that focuses on how changes in cell volume can regulate cell functions such as cell migration, proliferation, and programmed cell death.

  1. Smurf1 regulation of DAB2IP controls cell proliferation and migration

    Science.gov (United States)

    Wan, Lixin; Inuzuka, Hiroyuki; Sun, Liankun; North, Brian J.

    2016-01-01

    Tumor cell proliferation, survival and migration are regulated by the deletion of ovarian carcinoma 2/disabled homolog 2 (DOC-2/DAB2) interacting protein (DAB2IP), a tumor suppressor that serves as a scaffold protein for H-Ras and TRAF2. Importantly, the oncogenic histone methyl-transferase EZH2 epigenetically down-regulates DAB2IP in a variety of tumors. Recently, we demonstrated that DAB2IP is negatively regulated by Akt-dependent phosphorylation and SCFFbw7-mediated degradation. Here, we further identify the oncoprotein Smurf1, an E3-ubiquitin ligase, as a novel negative regulator of DAB2IP. Smurf1-mediated cellular proliferation and migration are largely dependent on the presence of DAB2IP, suggesting that DAB2IP is a key effector molecule of Smurf1 oncogenic function. Additionally, we identify that similar to DAB2IP, Smurf1 is also a target of phosphorylation by both Akt1 and Akt2 kinases, which enhances Smurf1 abundance, leading to a reduction in DAB2IP. Given the role of DAB2IP in tumorigenesis and metastasis, our data identify Smurf1 as an upstream oncogenic factor that negatively regulates DAB2IP to govern aberrant cell growth and migration. PMID:27036023

  2. KSHV-Mediated Regulation of Par3 and SNAIL Contributes to B-Cell Proliferation.

    Directory of Open Access Journals (Sweden)

    Hem C Jha

    2016-07-01

    Full Text Available Studies have suggested that Epithelial-Mesenchymal Transition (EMT and transformation is an important step in progression to cancer. Par3 (partitioning-defective protein is a crucial factor in regulating epithelial cell polarity. However, the mechanism by which the latency associated nuclear antigen (LANA encoded by Kaposi's Sarcoma associated herpesvirus (KSHV regulates Par3 and EMTs markers (Epithelial-Mesenchymal Transition during viral-mediated B-cell oncogenesis has not been fully explored. Moreover, several studies have demonstrated a crucial role for EMT markers during B-cell malignancies. In this study, we demonstrate that Par3 is significantly up-regulated in KSHV-infected primary B-cells. Further, Par3 interacted with LANA in KSHV positive and LANA expressing cells which led to translocation of Par3 from the cell periphery to a predominantly nuclear signal. Par3 knockdown led to reduced cell proliferation and increased apoptotic induction. Levels of SNAIL was elevated, and E-cadherin was reduced in the presence of LANA or Par3. Interestingly, KSHV infection in primary B-cells led to enhancement of SNAIL and down-regulation of E-cadherin in a temporal manner. Importantly, knockdown of SNAIL, a major EMT regulator, in KSHV cells resulted in reduced expression of LANA, Par3, and enhanced E-cadherin. Also, SNAIL bound to the promoter region of p21 and can regulate its activity. Further a SNAIL inhibitor diminished NF-kB signaling through upregulation of Caspase3 in KSHV positive cells in vitro. This was also supported by upregulation of SNAIL and Par3 in BC-3 transplanted NOD-SCID mice which has potential as a therapeutic target for KSHV-associated B-cell lymphomas.

  3. KSHV-Mediated Regulation of Par3 and SNAIL Contributes to B-Cell Proliferation

    Science.gov (United States)

    Jha, Hem C.; Sun, Zhiguo; Upadhyay, Santosh K.; El-Naccache, Darine W.; Singh, Rajnish K.; Sahu, Sushil K.; Robertson, Erle S.

    2016-01-01

    Studies have suggested that Epithelial–Mesenchymal Transition (EMT) and transformation is an important step in progression to cancer. Par3 (partitioning-defective protein) is a crucial factor in regulating epithelial cell polarity. However, the mechanism by which the latency associated nuclear antigen (LANA) encoded by Kaposi's Sarcoma associated herpesvirus (KSHV) regulates Par3 and EMTs markers (Epithelial-Mesenchymal Transition) during viral-mediated B-cell oncogenesis has not been fully explored. Moreover, several studies have demonstrated a crucial role for EMT markers during B-cell malignancies. In this study, we demonstrate that Par3 is significantly up-regulated in KSHV-infected primary B-cells. Further, Par3 interacted with LANA in KSHV positive and LANA expressing cells which led to translocation of Par3 from the cell periphery to a predominantly nuclear signal. Par3 knockdown led to reduced cell proliferation and increased apoptotic induction. Levels of SNAIL was elevated, and E-cadherin was reduced in the presence of LANA or Par3. Interestingly, KSHV infection in primary B-cells led to enhancement of SNAIL and down-regulation of E-cadherin in a temporal manner. Importantly, knockdown of SNAIL, a major EMT regulator, in KSHV cells resulted in reduced expression of LANA, Par3, and enhanced E-cadherin. Also, SNAIL bound to the promoter region of p21 and can regulate its activity. Further a SNAIL inhibitor diminished NF-kB signaling through upregulation of Caspase3 in KSHV positive cells in vitro. This was also supported by upregulation of SNAIL and Par3 in BC-3 transplanted NOD-SCID mice which has potential as a therapeutic target for KSHV-associated B-cell lymphomas. PMID:27463802

  4. TAZ regulates cell proliferation and sensitivity to vitamin D3 in intrahepatic cholangiocarcinoma.

    Science.gov (United States)

    Xiao, Heng; Tong, Rongliang; Yang, Beng; Lv, Zhen; Du, Chengli; Peng, Chuanhui; Ding, Chaofeng; Cheng, Shaobing; Zhou, Lin; Xie, Haiyang; Wu, Jian; Zheng, Shusen

    2016-10-28

    The transcriptional coactivator with PDZ binding motif (TAZ) is reported as one of the nuclear effectors of Hippo-related pathways. TAZ is found overexpressed in many primary tumors and could regulate many biological processes. However, little is known about the role of TAZ in Intrahepatic Cholangiocarcinoma (ICC). In this study, we found that TAZ is expressed more in ICC tissues than in peritumoral tissue, and a robust expression of TAZ is correlated with a lower overall survival rate of ICC patients after hepatectomy. TAZ knockdown results in an increase in cell apoptosis, a promotion of cell-cycle arrest and a decrease in tumor size and weight in vivo through an increased expression of p53. Vitamin D3 can also inhibit cell proliferation by promoting p53 expression in ICC cells. A reduction in TAZ can also enhance the sensitivity of tumor cells to vitamin D by regulating the p53/CYP24A1 pathway. In conclusion, TAZ is associated with the proliferation and drug-resistance of ICC cells, and could be a novel therapeutic target for the treatment of ICC.

  5. Autocrine regulation of cell proliferation by estrogen receptor-alpha in estrogen receptor-alpha-positive breast cancer cell lines

    Directory of Open Access Journals (Sweden)

    Pan Zhongzong

    2009-01-01

    Full Text Available Abstract Background Estrogen receptor-α (ERα is essential for mammary gland development and is a major oncogene in breast cancer. Since ERα is not colocalized with the cell proliferation marker Ki-67 in the normal mammary glands and the majority of primary breast tumors, it is generally believed that paracrine regulation is involved in ERα mediated cell proliferation. In the paracrine model, ERα-positive cells don't proliferate but will release some paracrine growth factors to stimulate the neighboring cells to proliferate. In a subpopulation of cancer cells in some primary breast tumors, however, ERα does colocalize with the cell proliferation marker Ki-67, suggesting an autocrine regulation by ERα in some primary breast tumors. Methods Colocalization of ERα with Ki-67 in ERα-positive breast cancer cell lines (MCF-7, T47D, and ZR75-1 was evaluated by immunofluorescent staining. Cell cycle phase dependent expression of ERα was determined by co-immunofluorescent staining of ERα and the major cyclins (D, E, A, B, and by flow cytometry analysis of ERαhigh cells. To further confirm the autocrine action of ERα, MCF-7 cells were growth arrested by ICI182780 treatment, followed by treatment with EGFR inhibitor, before estrogen stimulation and analyses for colocalization of Ki-67 and ERα and cell cycle progression. Results Colocalization of ERα with Ki-67 was present in all three ERα-positive breast cancer cell lines. Unlike that in the normal mammary glands and the majority of primary breast tumors, ERα is highly expressed throughout the cell cycle in MCF-7 cells. Without E2 stimulation, MCF-7 cells released from ICI182780 treatment remain at G1 phase. E2 stimulation of ICI182780 treated cells, however, promotes the expression and colocalization of ERα and Ki-67 as well as the cell cycle progressing through the S and G2/M phases. Inhibition of EGFR signaling does not inhibit the autocrine action of ERα. Conclusion Our data indicate

  6. Androgens regulate Hedgehog signalling and proliferation in androgen-dependent prostate cells.

    Science.gov (United States)

    Sirab, Nanor; Terry, Stéphane; Giton, Frank; Caradec, Josselin; Chimingqi, Mihelaiti; Moutereau, Stéphane; Vacherot, Francis; de la Taille, Alexandre; Kouyoumdjian, Jean-Claude; Loric, Sylvain

    2012-09-15

    Prostate cancer (PCa) is androgen sensitive in its development and progression to metastatic disease. Hedgehog (Hh) pathway activation is important in the initiation and growth of various carcinomas including PCa. We and others have observed aberrations of Hh pathway during the progression of PCa to the castration-resistant state. The involvement of androgen signalling in Hh pathway activation, however, remains largely elusive. Here we investigate the direct role of androgen signalling on Hh pathway. We examined the effect of Dihydrosterone (DHT), antiandrogen, bicalutamide, and Hh pathway inhibitor, KAAD-cyclopamine in four human prostate cell lines (two cancerous: LNCaP, VCaP, and two normal: PNT2 and PNT2-ARm which harbours a mutant version of androgen receptor (AR) that is commonly found in LNCaP). Cell proliferation as well as Hh pathway members (SHH, IHH, DHH, GLI, PTCH) mRNA expression levels were assessed. We showed that KAAD-cyclopamine decreased cell proliferation of DHT-stimulated LNCaP, VCaP and PNT2-ARm cells. SHH expression was found to be downregulated by DHT in all AR posititve cells. The negative effect of DHT on SHH expression was counteracted when cells were treated by bicalutamide. Importantly, KAAD-cyclopamine treatment seemed to inhibit AR activity. Moreover, bicalutamide as well as KAAD-cyclopamine treatments induced GLI and PTCH expression in VCaP and PNT2-ARm. Our results suggest that Hh pathway activity can be regulated by androgen signalling. Specifically, we show that the DHT-induced inhibition of Hh pathway is AR dependent. The mutual interaction between these two pathways might be important in the regulation of cell proliferation in PCa.

  7. Regulation of cell proliferation and apoptosis in neuroblastoma cells by ccp1, a FGF2 downstream gene

    Directory of Open Access Journals (Sweden)

    Inman Gareth J

    2010-11-01

    Full Text Available Abstract Background Coiled-coil domain containing 115 (Ccdc115 or coiled coil protein-1 (ccp1 was previously identified as a downstream gene of Fibroblast Growth Factor 2 (FGF2 highly expressed in embryonic and adult brain. However, its function has not been characterised to date. Here we hypothesized that ccp1 may be a downstream effecter of FGF2, promoting cell proliferation and protecting from apoptosis. Methods Forced ccp1 expression in mouse embryonic fibroblast (MEF and neuroblastoma SK-N-SH cell line, as well as down-regulation of ccp1 expression by siRNA in NIH3T3, was used to characterize the role of ccp1. Results Ccp1 over-expression increased cell proliferation, whereas down-regulation of ccp1 expression reduced it. Ccp1 was able to increase cell proliferation in the absence of serum. Furthermore, ccp1 reduced apoptosis upon withdrawal of serum in SK-N-SH. The mitogen-activated protein kinase (MAPK or ERK Kinase (MEK inhibitor, U0126, only partially inhibited the ccp1-dependent BrdU incorporation, indicating that other signaling pathway may be involved in ccp1-induced cell proliferation. Induction of Sprouty (SPRY upon FGF2 treatment was accelerated in ccp1 over-expressing cells. Conclusions All together, the results showed that ccp1 regulates cell number by promoting proliferation and suppressing cell death. FGF2 was shown to enhance the effects of ccp1, however, it is likely that other mitogenic factors present in the serum can also enhance the effects. Whether these effects are mediated by FGF2 influencing the ccp1 function or by increasing the ccp1 expression level is still unclear. At least some of the proliferative regulation by ccp1 is mediated by MAPK, however other signaling pathways are likely to be involved.

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

    Science.gov (United States)

    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

  9. Molecular manipulation targeting regulation of dopaminergic differentiation and proliferation of neural stem cells or pluripotent stem cells.

    Science.gov (United States)

    Ding, Yin-Xiu; Wei, Li-Chun; Wang, Ya-Zhou; Cao, Rong; Wang, Xi; Chen, Liang-Wei

    2011-06-01

    Parkinson's disease (PD) is a severe deliberating neurological disease caused by progressive degenerative death of dopaminergic neurons in the substantia nigra of midbrain. While cell replacement strategy by transplantation of neural stem cells and inducement of dopaminergic neurons is recommended for the treatment of PD, understanding the differentiation mechanism and controlled proliferation of grafted stem cells remain major concerns in their clinical application. Here we review recent studies on molecular signaling pathways in regulation of dopaminergic differentiation and proliferation of stem cells, particularly Wnt/beta-catenin signaling in stimulating formation of the dopaminergic phenotype, Notch signaling in inhibiting stem cell differentiation, and Sonic hedgehog functioning in neural stem cell proliferation and neuronal cell production. Activation of oncogenes involved in uncontrolled proliferation or tumorigenicity of stem cells is also discussed. It is proposed that a selective molecular manipulation targeting strategy will greatly benefit cell replacement therapy for PD by effectively promoting dopaminergic neuronal cell generation and reducing risk of tumorigenicity of in vivo stem cell applications.

  10. Donor lung derived myeloid and plasmacytoid dendritic cells differentially regulate T cell proliferation and cytokine production

    Directory of Open Access Journals (Sweden)

    Benson Heather L

    2012-03-01

    Full Text Available Abstract Background Direct allorecognition, i.e., donor lung-derived dendritic cells (DCs stimulating recipient-derived T lymphocytes, is believed to be the key mechanism of lung allograft rejection. Myeloid (cDCs and plasmacytoid (pDCs are believed to have differential effects on T cell activation. However, the roles of each DC type on T cell activation and rejection pathology post lung transplantation are unknown. Methods Using transgenic mice and antibody depletion techniques, either or both cell types were depleted in lungs of donor BALB/c mice (H-2d prior to transplanting into C57BL/6 mice (H-2b, followed by an assessment of rejection pathology, and pDC or cDC-induced proliferation and cytokine production in C57BL/6-derived mediastinal lymph node T cells (CD3+. Results Depleting either DC type had modest effect on rejection pathology and T cell proliferation. In contrast, T cells from mice that received grafts depleted of both DCs did not proliferate and this was associated with significantly reduced acute rejection scores compared to all other groups. cDCs were potent inducers of IFNγ, whereas both cDCs and pDCs induced IL-10. Both cell types had variable effects on IL-17A production. Conclusion Collectively, the data show that direct allorecognition by donor lung pDCs and cDCs have differential effects on T cell proliferation and cytokine production. Depletion of both donor lung cDC and pDC could prevent the severity of acute rejection episodes.

  11. Normal stroma suppresses cancer cell proliferation via mechanosensitive regulation of JMJD1a-mediated transcription.

    Science.gov (United States)

    Kaukonen, Riina; Mai, Anja; Georgiadou, Maria; Saari, Markku; De Franceschi, Nicola; Betz, Timo; Sihto, Harri; Ventelä, Sami; Elo, Laura; Jokitalo, Eija; Westermarck, Jukka; Kellokumpu-Lehtinen, Pirkko-Liisa; Joensuu, Heikki; Grenman, Reidar; Ivaska, Johanna

    2016-01-01

    Tissue homeostasis is dependent on the controlled localization of specific cell types and the correct composition of the extracellular stroma. While the role of the cancer stroma in tumour progression has been well characterized, the specific contribution of the matrix itself is unknown. Furthermore, the mechanisms enabling normal-not cancer-stroma to provide tumour-suppressive signals and act as an antitumorigenic barrier are poorly understood. Here we show that extracellular matrix (ECM) generated by normal fibroblasts (NFs) is softer than the CAF matrix, and its physical and structural features regulate cancer cell proliferation. We find that normal ECM triggers downregulation and nuclear exit of the histone demethylase JMJD1a resulting in the epigenetic growth restriction of carcinoma cells. Interestingly, JMJD1a positively regulates transcription of many target genes, including YAP/TAZ (WWTR1), and therefore gene expression in a stiffness-dependent manner. Thus, normal stromal restricts cancer cell proliferation through JMJD1a-dependent modulation of gene expression. PMID:27488962

  12. PDE8 regulates rapid Teff cell adhesion and proliferation independent of ICER.

    Directory of Open Access Journals (Sweden)

    Amanda G Vang

    Full Text Available BACKGROUND: Abolishing the inhibitory signal of intracellular cAMP by phosphodiesterases (PDEs is a prerequisite for effector T (Teff cell function. While PDE4 plays a prominent role, its control of cAMP levels in Teff cells is not exclusive. T cell activation has been shown to induce PDE8, a PDE isoform with 40- to 100-fold greater affinity for cAMP than PDE4. Thus, we postulated that PDE8 is an important regulator of Teff cell functions. METHODOLOGY/PRINCIPAL FINDINGS: We found that Teff cells express PDE8 in vivo. Inhibition of PDE8 by the PDE inhibitor dipyridamole (DP activates cAMP signaling and suppresses two major integrins involved in Teff cell adhesion. Accordingly, DP as well as the novel PDE8-selective inhibitor PF-4957325-00 suppress firm attachment of Teff cells to endothelial cells. Analysis of downstream signaling shows that DP suppresses proliferation and cytokine expression of Teff cells from Crem-/- mice lacking the inducible cAMP early repressor (ICER. Importantly, endothelial cells also express PDE8. DP treatment decreases vascular adhesion molecule and chemokine expression, while upregulating the tight junction molecule claudin-5. In vivo, DP reduces CXCL12 gene expression as determined by in situ probing of the mouse microvasculature by cell-selective laser-capture microdissection. CONCLUSION/SIGNIFICANCE: Collectively, our data identify PDE8 as a novel target for suppression of Teff cell functions, including adhesion to endothelial cells.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-08-17

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

  14. NFAT5 promotes proliferation and migration of lung adenocarcinoma cells in part through regulating AQP5 expression

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Kai, E-mail: gk161@163.com [Department of Respiration, Tangdu Hospital, Fourth Military Medical University, Xi' an 710038 (China); Department of Respiration, 161th Hospital, PLA, Wuhan 430015 (China); Jin, Faguang, E-mail: jinfag@fmmu.edu.cn [Department of Respiration, Tangdu Hospital, Fourth Military Medical University, Xi' an 710038 (China)

    2015-09-25

    The osmoregulated transcription factor nuclear factor of activated T-cells 5(NFAT5), has been found to play important roles in the development of many kinds of human cancers, including breast cancer, colon carcinoma, renal cell carcinoma and melanoma. The aim of the present study was to determine whether NFAT5 is involved in the proliferation and migration of lung adenocarcinoma cells. We found that NFAT5 was upregulated in lung adenocarcinoma cells and knockdown of NFAT5 decreased proliferation and migration of the cells, accompanied by a significant reduction in the expression of AQP5. AQP5 was upregulated in lung adenocarcinoma cells and knockdown of AQP5 also inhibited proliferation and migration of the cells as knockdown of NFAT5 did. Moreover, overexpression of NFAT5 promoted proliferation and migration of lung adenocarcinoma cells, accompanied by a significant increase in the expression of AQP5. These results indicate that NFAT5 plays important roles in proliferation and migration of human lung adenocarcinoma cells through regulating AQP5 expression, providing a new therapeutic option for lung adenocarcinoma therapy. - Highlights: • NFAT5 expression is higher in lung adenocarcinoma cells compared with normal cells. • NFAT5 knockdown decreases proliferation and migration of lung adenocarcinoma cells. • Knockdown of NFAT5 reduces AQP5 expression in human lung adenocarcinoma cells. • Overexpression of NFAT5 promotes proliferation and migration of lung adenocarcinoma cells. • Overexpression of NFAT5 increases AQP5 expression in human lung adenocarcinoma cells.

  15. NFAT5 promotes proliferation and migration of lung adenocarcinoma cells in part through regulating AQP5 expression

    International Nuclear Information System (INIS)

    The osmoregulated transcription factor nuclear factor of activated T-cells 5(NFAT5), has been found to play important roles in the development of many kinds of human cancers, including breast cancer, colon carcinoma, renal cell carcinoma and melanoma. The aim of the present study was to determine whether NFAT5 is involved in the proliferation and migration of lung adenocarcinoma cells. We found that NFAT5 was upregulated in lung adenocarcinoma cells and knockdown of NFAT5 decreased proliferation and migration of the cells, accompanied by a significant reduction in the expression of AQP5. AQP5 was upregulated in lung adenocarcinoma cells and knockdown of AQP5 also inhibited proliferation and migration of the cells as knockdown of NFAT5 did. Moreover, overexpression of NFAT5 promoted proliferation and migration of lung adenocarcinoma cells, accompanied by a significant increase in the expression of AQP5. These results indicate that NFAT5 plays important roles in proliferation and migration of human lung adenocarcinoma cells through regulating AQP5 expression, providing a new therapeutic option for lung adenocarcinoma therapy. - Highlights: • NFAT5 expression is higher in lung adenocarcinoma cells compared with normal cells. • NFAT5 knockdown decreases proliferation and migration of lung adenocarcinoma cells. • Knockdown of NFAT5 reduces AQP5 expression in human lung adenocarcinoma cells. • Overexpression of NFAT5 promotes proliferation and migration of lung adenocarcinoma cells. • Overexpression of NFAT5 increases AQP5 expression in human lung adenocarcinoma cells

  16. Cell type-dependent Erk-Akt pathway crosstalk regulates the proliferation of fetal neural progenitor cells.

    Science.gov (United States)

    Rhim, Ji Heon; Luo, Xiangjian; Gao, Dongbing; Xu, Xiaoyun; Zhou, Tieling; Li, Fuhai; Wang, Ping; Wong, Stephen T C; Xia, Xiaofeng

    2016-01-01

    Neural progenitor (NP) cells are the multipotent cells that produce neurons and glia in the central nervous system. Compounds regulating their proliferation are key to both understanding brain development and unlocking their potential in regenerative repair. We discuss a chemical screen that unexpectedly identified inhibitors of Erk signaling potently promoting the self-renewing divisions of fetal NP cells. This occurred through crosstalk between Erk and Akt signaling cascades. The crosstalk mechanism is cell type-specific, and is not detected in adult NP cells as well as brain tumor cells. The mechanism was also shown to be independent from the GSK-3 signaling pathway, which has been reported to be a major regulator of NP cell homeostasis and inhibitors to which were also identified in the screen. In vitro Erk inhibition led to the prolonged rapid expansion of fetal NP cells while retaining their multipotency. In vivo inhibitor administration significantly inhibited the neuronal differentiation, and resulted in increased proliferative progenitor cells in the ventricular/subventricular zone (VZ/SVZ) of the embryonic cortex. Our results uncovered a novel regulating pathway for NP cell proliferation in the developing brain. The discovery provides a pharmacological basis for in vitro expansion and in vivo manipulation of NP cells. PMID:27211495

  17. Clinicopathological analysis of UHRF1 expression in medulloblastoma tissues and its regulation on tumor cell proliferation.

    Science.gov (United States)

    Zhang, Zhen-Yu; Cai, Jia-Jun; Hong, Jin; Li, Kay Ka-Wai; Ping, Zhou; Wang, Yin; Ng, Ho-Keung; Yao, Yu; Mao, Ying

    2016-09-01

    Studies have showed the involvement of ubiquitin-like with PHD and RING finger domains 1 (UHRF1) in tumorigenesis and progression. This study focused on the relationships between UHRF1 and medulloblastoma (MB). Immunostaining and western blotting demonstrated differential expression of UHRF1 in MB tissues and no UHRF1 expression in normal cerebellum tissues. Univariate survival analysis revealed MB patients with high UHRF1 expression had significantly shorter OS and PFS than patients with low UHRF1 (OS p = 0.009, PFS p = 0.003). Multivariate analysis illustrated that UHRF1 expression level is an independent prognostic factor influencing the OS and PFS (OS p = 0.038, PFS p = 0.014). UHRF1 expression levels were significantly different among molecular subgroups of MB (p = 0.003). Down-regulation of UHRF1 by RNAi inhibited proliferation and clonogenic ability of MB cell lines with cell cycle arrest in G1/G2-phase. Meanwhile, cells transfected with lenti-shUHRF1 showed increased p16 expression and location shift of CDK4 in MB cells. These findings indicate UHRF1 may promote cell proliferation and be a potential biomarker that can be used as a prognostic parameter and a therapeutic target for MB. PMID:27449774

  18. Cell cycle and anti-estrogen effects synergize to regulate cell proliferation and ER target gene expression.

    Directory of Open Access Journals (Sweden)

    Mathieu Dalvai

    Full Text Available Antiestrogens are designed to antagonize hormone induced proliferation and ERalpha target gene expression in mammary tumor cells. Commonly used drugs such as OH-Tamoxifen and ICI 182780 (Fulvestrant block cell cycle progression in G0/G1. Inversely, the effect of cell cycle stage on ER regulated gene expression has not been tested directly. We show that in ERalpha-positive breast cancer cells (MCF-7 the estrogen receptor gene and downstream target genes are cell cycle regulated with expression levels varying as much as three-fold between phases of the cell cycle. Steroid free culture conditions commonly used to assess the effect of hormones or antiestrogens on gene expression also block MCF-7 cells in G1-phase when several ERalpha target genes are overexpressed. Thus, cell cycle effects have to be taken into account when analyzing the impact of hormonal treatments on gene transcription. We found that antiestrogens repress transcription of several ERalpha target genes specifically in S phase. This observation corroborates the more rapid and strong impact of antiestrogen treatments on cell proliferation in thymidine, hydroxyurea or aphidicolin arrested cells and correlates with an increase of apoptosis compared to similar treatments in lovastatin or nocodazol treated cells. Hence, cell cycle effects synergize with the action of antiestrogens. An interesting therapeutic perspective could be to enhance the action of anti-estrogens by associating hormone-therapy with specific cell cycle drugs.

  19. HERBAL MEDICINE 960 RECIPE REGULATES THE PROLIFERATION AND APOPTOSIS OF HUMAN HEPATOMA CELL LINE SMMC-7721 CELLS

    Institute of Scientific and Technical Information of China (English)

    王昌俊; 李建军; 陈庆强; 陈伟; 钱伯文

    2001-01-01

    To investigate the mechanism of 960 recipe regulating the proliferation and apoptosis of human hepatoma SMMC7721 cells.Methods 960 recipe-containing serum was derived from rats that pre-treated with 960 recipe through gastrogavage, and was added to cultured human hepatoma SMMC-7721 cells while the normal rat serum was tested as control. Cell proliferation was measured with 3H-TdR incorporation. Cell morphology was tested by acridine orange staining. Cell apoptosis and expressions of p53, bcl-2 and p21ras gene protein were analyzed with flow cytometry.Results After treating with 960 recipe, the inhibitory rate of 3H-TdR was 42.2% for 48h. Cell morphology showed typical apoptotic cells with condensed and fragmented nuclei. There were typical apoptotic peaks in DNA histogram, the apoptotic rate being 21.25% and 27.77% for 24h, 48h respectively. Cell cycle analysis showed that cells were arrested at S-phase by treating with 960 recipe for 24h and at G0/G1 phase for 48h. The expression of p53 increased, but bcl-2 and ras were reduced by treating with 960 recipe for 24h.Conclusion 960 recipe can inhibit proliferation and induce apoptosis of human hepatoma cells, and affect the cell cycle, the expression of oncogene and tumor suppressor gene. These might be the main antihepatoma mechanisms of 960 recipe.

  20. Onychin inhibits proliferation of vascular smooth muscle cells by regulating cell cycle

    Institute of Scientific and Technical Information of China (English)

    Ming YANG; Hong-lin HUANG; Bing-yang ZHU; Qin-hui TUO; Duan-fang LIAO

    2005-01-01

    Aim: To investigate the effects of onychin on the proliferation of cultured rat artery vascular smooth muscle cells (VSMCs) in the presence of 10% new-borncalf serum (NCS). Methods: Rat VSMCs were incubated with onychin 1-50 μmol/L or genistein 10 μmol/L in the presence of 10% NCS for 24 h. The proliferation of VSMCs was measured by cell counting and MTS/PMS colorimetric assays. Cell cycle progression was evaluated by flow cytometry. Retinoblastoma (Rb) phosphorylation, and expression of cyclin D1 and cyclin E were measured by Western blot assays. The tyrosine phosphorylation of ERK1/2 was examined by immunoprecipitation techniques using anti-phospho-tyrosine antibodies. Results: The proliferation of VSMCs was accelerated significantly in the presence of 10% NCS. Onychin reduced the metabolic rate of MTS and the cell number of VSMCs in the presence of 10% NCS in a dose-dependent manner. Flow cytometry analy sis revealed that the G1-phase fraction ratio in the onychin group was higher than that in the 10% NCS group (85.2% vs 70.0%, P<0.01), while the S-phase fraction ratio in the onychin group was lower than that in 10% NCS group (4.3% vs 16.4%, P<0.01). Western blot analysis showed that onychin inhibited Rb phos phorylation and reduced the expression of cyclin D1 and cyclin E. The effects of onychin on proliferation, the cell cycle and the expression of cyclins in VSMCs were similar to those of genistein, an inhibitor of tyrosine kinase. Furthermore immunoprecipitation studies showed that both onychin and genistein markedly inhibited the tyrosine phosphorylation of ERK1/2 induced by 10% NCS.Conclusion: Onychin inhibits the proliferation of VSMCs through G1 phase cell cycle arrest by decreasing the tyrosine phosphorylation of ERK1/2, and the expression of cyclin D1 and cyclin E, and sequentially inhibiting Rb phosphorylation.

  1. miR-708/LSD1 axis regulates the proliferation and invasion of breast cancer cells.

    Science.gov (United States)

    Ma, Lin; Ma, Shan; Zhao, Guimei; Yang, Longqiu; Zhang, Peng; Yi, Qingting; Cheng, Shuguang

    2016-04-01

    Breast cancer is one of the most common malignant tumors in women worldwide. The microRNAs (miRNAs) are small, noncoding RNAs that regulate various biological processes, including breast cancer. miR-708 played an important role in a variety of cancers. However, its involvement in breast cancer remains largely unclear. In this study, we found that forced the expression of miR-708 in breast cancer cell lines decreased cell proliferation and invasion, whereas inhibition of miR-708 increased cell growth and invasion. miR-708 could directly target the LSD1 3'UTR to downregulate the expression. Further studies suggested that inhibition of LSD1 could phenocopied function of the miR-708 overexpression in MDA-MB-231 cells .Overexpression of LSD1 could counteract the effects of miR-708 on the proliferation and invasion. Taken together, the results indicate that miR-708 may function as a tumor suppressor gene in breast cancer development, and miR-708/LSD1 axis may be a therapeutic intervention in breast cancer in the future. PMID:26833707

  2. Regulation of cell proliferation by the E2F transcription factors

    DEFF Research Database (Denmark)

    Helin, K

    1998-01-01

    Experimental data generated in the past year have further emphasized the essential role for the E2F transcription factors in the regulation of cell proliferation. Genetic studies have shown that E2F activity is required for normal development in fruitflies, and the generation of E2F-1(-/-) mice has...... demonstrated that individual members of the E2F transcription factor family are likely to have distinct roles in mammalian development and homeostasis. Additional mechanisms regulating the activity of the E2F transcription factors have been reported, including subcellular localization and proteolysis of the E2......Fs in the proteasomes. Novel target genes for the E2F transcription factors have been identified that link the E2Fs directly to the initiation of DNA replication....

  3. Regulation of Trib2 by an E2F1-C/EBPα feedback loop in AML cell proliferation

    DEFF Research Database (Denmark)

    Rishi, Loveena; Hannon, Maura; Salomè, Mara;

    2014-01-01

    α (C/EBPα)-p42, occurs in acute myeloid leukemia (AML), resulting in the perturbation of cell cycle and apoptosis, emphasizing its importance in the molecular pathogenesis of AML. Here we show that E2F family members directly regulate Trib2 in leukemic cells and identify a feedback regulatory loop...... cycle or Trib2 knockdown resulted in a block in AML cell proliferation. Our work proposes a novel paradigm whereby E2F1 plays a key role in the regulation of Trib2 expression important for AML cell proliferation control. Importantly, we identify the contribution of dysregulated C/EBPα and E2F1 to...

  4. Curcumin regulates hepatoma cell proliferation and apoptosis through the Notch signaling pathway

    OpenAIRE

    Liu, Zheng-cai; Yang, Zhao-Xu; Zhou, Jing-Shi; Zhang, Hong-Tao; Huang, Qi-Ke; Dang, Li-Li; Liu, Guang-Xin; Tao, Kai-shan

    2014-01-01

    Curcumin has become a compound of interest for its antioxidant and anti-neoplastic properties. This study sought to determine the effect of curcumin administration on cell proliferation and apoptosis in hepatoma cells. SMMC-7721 hepatoma cells were treated with 10, 30, or 90 μM curcumin solution, with DMEM alone (negative control), or with 20 mg/L fluorouracil (positive control). MTT colorimetry detected significant differences in the rates of cell proliferation inhibition following curcumin ...

  5. Y-27632 Increases Sensitivity of PANC-1 Cells to Epigallocatechin Gallate (EGCG) in Regulating Cell Proliferation and Migration

    Science.gov (United States)

    Liu, Xing; Bi, Yongyi

    2016-01-01

    Background The study aimed to investigate the inhibitory effect of (1R,4r)-4-((R)-1-aminoethyl)-N-(pyridin-4-yl) cyclohexanecarboxamide (Y-27632) and (−)-epigallocatechin-3-gallate (EGCG) on the proliferation and migration of PANC-1 cells. EGCG, found in green tea, has been previously shown to be one of the most abundant and powerful catechins in cancer prevention and treatment. Y-27632, a selective inhibitor of rho-associated protein kinase 1, is widely used in treating cardiovascular disease, inflammation, and cancer. Material/Methods PANC-1 cells, maintained in Dulbecco’s Modified Eagle’s Medium, were treated with dimethyl sulfoxide (control) as well as different concentrations (20, 40, 60, and 80 μg/mL) of EGCG for 48 h. In addition, PANC-1 cells were treated separately with 60 μg/mL EGCG, 20 μM Y-27632, and EGCG combined with Y-27632 (60 μg/mL EGCG + 20 μM Y-27632) for 48 h. The effect of EGCG and Y-27632 on the proliferation and migration of PANC-1 cells was evaluated using Cell Counting Kit-8 and transwell migration assays. The expression of peroxisome proliferator–activated receptor alpha (PPARα) and Caspase-3 mRNA was determined by Quantitative real-time polymerase chain reaction (RT-qPCR). Results EGCG (20–80 μg/mL) inhibited cell viability in a dose-dependent manner. Y-27632 enhanced the sensitivity of PANC-1 cells to EGCG (by increasing the expression of PPARα and Caspase-3 mRNA) and suppressed cell proliferation. PANC-1 cell migration was inhibited by treatment with a combination of EGCG and Y-27632. Conclusions Y-27632 increases the sensitivity of PANC-1 cells to EGCG in regulating cell proliferation and migration, which is likely to be related to the expression of PPARα mRNA and Caspase-3 mRNA. PMID:27694793

  6. WISP-1 overexpression upregulates cell proliferation in human salivary gland carcinomas via regulating MMP-2 expression

    Science.gov (United States)

    Li, Fu-Jun; Wang, Xin-Juan; Zhou, Xiao-Li

    2016-01-01

    Background WISP-1 is a member of the CCN family of growth factors and has been reported to play an important role in tumorigenesis by triggering downstream events via integrin signaling. However, little is known about the role of WISP-1 in proliferation of salivary gland carcinoma (SGC) cells. Methods In this study, we investigated the WISP-1 expression in SGC tissues via immunohistochemical staining, Western blotting assay, and real-time quantitative polymerase chain reaction method, and then evaluated the regulatory role of WISP-1 in the growth of SGC A-253 cells. In addition, the role of MMP-2 in the WISP-1-mediated growth regulation was also investigated. Results It was demonstrated that the WISP-1 expression was upregulated at both mRNA and protein levels in 15 of 21 SGC tumor tissues, compared to the non-tumor tissues (five of 21), associated with the lymph node dissection and bone invasion. The in vitro CCK-8 assay and colony-forming assay demonstrated that the exogenous WISP-1 treatment or the WISP-1 overexpression promoted the growth of A-253 cells. In addition, we confirmed that the WISP-1 overexpression upregulated the MMP-2 expression in A-253 cells with the gain-of-function and loss-of-function strategies, and that the MMP-2 knockdown attenuated the WISP-1-mediated growth promotion of A-253 cells. Conclusion We found that WISP-1 was overexpressed in the human SGCs, and the WISP-1 overexpression promoted the salivary gland cell proliferation via upregulating MMP-2 expression. Our study recognized the oncogenic role of WISP-1 in human SGCs, which could serve as a potential target for anticancer therapy. PMID:27799801

  7. Peroxisome proliferator-activated receptor γ ligands regulate neural stem cell proliferation and differentiation in vitro and in vivo

    OpenAIRE

    Morales-García, José A.; Luna Medina, Rosario de; Alfaro-Cervello, Clara; Cortés-Canteli, Marta; Santos, Ángel; García-Verdugo, J. M.; Pérez Castillo, Ana

    2011-01-01

    Peroxisome proliferator-activated receptor gamma (PPARγ) belongs to a family of ligand-activated nuclear receptors and its ligands are known to control many physiological and pathological situations. Its role in the central nervous system has been under intense analysis during the last years. Here we show a novel function for PPARγ in controlling stem cell expansion in the adult mammalian brain. Adult rats treated with pioglitazone, a specific ligand of PPARγ, had elevated numbers of prolifer...

  8. A novel herbal formulation "LiverCare" differentially regulates primary rat hepatocyte and hepatocarcinoma cell proliferation in vitro.

    Science.gov (United States)

    Vidyashankar, Satyakumar; Varma, Sandeep R; Azeemudin, Mohammed; Godavarthi, Ashok; Krishna, Nandakumar S; Patki, Pralhad Sadashiv

    2011-09-01

    Hepatocyte growth factor (HGF) plays an important role in hepatocyte proliferation. HGF expression is regulated by various signaling molecules and nuclear receptors. In the present study, LiverCare(®) (LC), a novel polyherbal formulation (The Himalaya Drug Company, Bangalore, India), was evaluated for its efficacy, using co-cultures of primary rat hepatocytes-non-parenchymal cells (NPCs) and human hepatocellular carcinoma cells (HepG2). The rate of primary hepatocyte co-culture proliferation was significantly and dose-dependently increased by LC as determined by [(3)H]thymidine incorporation into newly synthesized DNA and cell proliferation assay. LC also increased HGF expression in primary hepatocyte co-culture. Albumin and urea content remained constant during proliferation of hepatocyte co-cultures in the presence of LC with decreased activity of alanine aminotransferase. It is interesting that LC inhibited incorporation of [(3)H]thymidine into DNA in HepG2 cells. LC enhanced peroxisome proliferator-activated receptor-α expression during hepatocyte proliferation, whereas tumor necrosis factor-α expression remained unaffected. In conclusion, our study clearly showed that LC differentially regulates primary rat hepatocytes and human hepatocarcinoma cell proliferation. LC may be a promising candidate for treating degenerative liver diseases by enhancing liver regeneration. PMID:21812649

  9. Effect of miR-451-mediated regulation of MIF expression on cell proliferation in human colon carcinoma cell line LoVo

    Institute of Scientific and Technical Information of China (English)

    孔帅

    2013-01-01

    Objective To investigate the effect of miR-451-mediated regulation of macrophage migration inhibitory factor(MIF) expression on cell proliferation in human colon carcinoma cell line LoVo.Methods A lentiviral vector

  10. Fragile x mental retardation protein regulates proliferation and differentiation of adult neural stem/progenitor cells.

    Directory of Open Access Journals (Sweden)

    Yuping Luo

    2010-04-01

    Full Text Available Fragile X syndrome (FXS, the most common form of inherited mental retardation, is caused by the loss of functional fragile X mental retardation protein (FMRP. FMRP is an RNA-binding protein that can regulate the translation of specific mRNAs. Adult neurogenesis, a process considered important for neuroplasticity and memory, is regulated at multiple molecular levels. In this study, we investigated whether Fmrp deficiency affects adult neurogenesis. We show that in a mouse model of fragile X syndrome, adult neurogenesis is indeed altered. The loss of Fmrp increases the proliferation and alters the fate specification of adult neural progenitor/stem cells (aNPCs. We demonstrate that Fmrp regulates the protein expression of several components critical for aNPC function, including CDK4 and GSK3beta. Dysregulation of GSK3beta led to reduced Wnt signaling pathway activity, which altered the expression of neurogenin1 and the fate specification of aNPCs. These data unveil a novel regulatory role for Fmrp and translational regulation in adult neurogenesis.

  11. RAF kinase activity regulates neuroepithelial cell proliferation and neuronal progenitor cell differentiation during early inner ear development.

    Directory of Open Access Journals (Sweden)

    Marta Magariños

    Full Text Available BACKGROUND: Early inner ear development requires the strict regulation of cell proliferation, survival, migration and differentiation, coordinated by the concerted action of extrinsic and intrinsic factors. Deregulation of these processes is associated with embryonic malformations and deafness. We have shown that insulin-like growth factor I (IGF-I plays a key role in embryonic and postnatal otic development by triggering the activation of intracellular lipid and protein kinases. RAF kinases are serine/threonine kinases that regulate the highly conserved RAS-RAF-MEK-ERK signaling cascade involved in transducing the signals from extracellular growth factors to the nucleus. However, the regulation of RAF kinase activity by growth factors during development is complex and still not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: By using a combination of qRT-PCR, Western blotting, immunohistochemistry and in situ hybridization, we show that C-RAF and B-RAF are expressed during the early development of the chicken inner ear in specific spatiotemporal patterns. Moreover, later in development B-RAF expression is associated to hair cells in the sensory patches. Experiments in ex vivo cultures of otic vesicle explants demonstrate that the influence of IGF-I on proliferation but not survival depends on RAF kinase activating the MEK-ERK phosphorylation cascade. With the specific RAF inhibitor Sorafenib, we show that blocking RAF activity in organotypic cultures increases apoptosis and diminishes the rate of cell proliferation in the otic epithelia, as well as severely impairing neurogenesis of the acoustic-vestibular ganglion (AVG and neuron maturation. CONCLUSIONS/SIGNIFICANCE: We conclude that RAF kinase activity is essential to establish the balance between cell proliferation and death in neuroepithelial otic precursors, and for otic neuron differentiation and axonal growth at the AVG.

  12. StearoylCoA desaturase-5: a novel regulator of neuronal cell proliferation and differentiation.

    Directory of Open Access Journals (Sweden)

    Debora I Sinner

    Full Text Available Recent studies have demonstrated that human stearoylCoA desaturase-1 (SCD1, a Δ9-desaturase that converts saturated fatty acids (SFA into monounsaturated fatty acids, controls the rate of lipogenesis, cell proliferation and tumorigenic capacity in cancer cells. However, the biological function of stearoylCoA desaturase-5 (SCD5, a second isoform of human SCD that is highly expressed in brain, as well as its potential role in human disease, remains unknown. In this study we report that the constitutive overexpression of human SCD5 in mouse Neuro2a cells, a widely used cell model of neuronal growth and differentiation, displayed a greater n-7 MUFA-to-SFA ratio in cell lipids compared to empty-vector transfected cells (controls. De novo synthesis of phosphatidylcholine and cholesterolesters was increased whereas phosphatidylethanolamine and triacylglycerol formation was reduced in SCD5-expressing cells with respect to their controls, suggesting a differential use of SCD5 products for lipogenic reactions. We also observed that SCD5 expression markedly accelerated the rate of cell proliferation and suppressed the induction of neurite outgrowth, a typical marker of neuronal differentiation, by retinoic acid indicating that the desaturase plays a key role in the mechanisms of cell division and differentiation. Critical signal transduction pathways that are known to modulate these processes, such epidermal growth factor receptor (EGFRAkt/ERK and Wnt, were affected by SCD5 expression. Epidermal growth factor-induced phosphorylation of EGFR, Akt and ERK was markedly blunted in SCD5-expressing cells. Furthermore, the activity of canonical Wnt was reduced whereas the non-canonical Wnt was increased by the presence of SCD5 activity. Finally, SCD5 expression increased the secretion of recombinant Wnt5a, a non-canonical Wnt, whereas it reduced the cellular and secreted levels of canonical Wnt7b. Our data suggest that, by a coordinated modulation of key

  13. Drosophila Follicle Stem Cells are regulated by proliferation and niche adhesion as well as mitochondria and ROS

    OpenAIRE

    Wang, Zhu A.; Huang, Jianhua; Kalderon, Daniel

    2012-01-01

    The mechanisms underlying adult stem cell behavior are likely to be diverse and have not yet been investigated systematically. Here we conducted an unbiased genetic screen using Drosophila ovarian follicle stem cells (FSCs) to probe essential functions regulating self-renewal of epithelial stem cells. Surprisingly, we find that niche adhesion emerge as the most commonly affected essential stem cell property, and that proliferation is critical for stem cell maintenance. We also find that PI3K ...

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

    Directory of Open Access Journals (Sweden)

    Liang-Dong Li

    Full Text Available 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.

  15. Differential regulation of cell proliferation in neurogenic zones in mice lacking cystine transport by xCT

    International Nuclear Information System (INIS)

    The cystine/glutamate exchanger (xCT) supplies intracellular cyst(e)ine for the production of glutathione, a major cellular anti-oxidant. xCT is enriched in brain regions associated with neurogenesis. Previous studies have shown that the malfunction of this protein greatly attenuates cell proliferation in vitro and is associated with brain atrophy in vivo. Using mice that are homozygous for a function-blocking deletion in xCT (Sut mice), we examined in vivo the role of xCT in cell proliferation in neurogenic regions of the subventricular zone (SVZ) and denate gyrus (DG) in the adult brain. Our results indicate that a high level of cellular proliferation in the adult brain persists even in the absence of functional xCT. Furthermore, in both young adult and middle-aged mice (3 and 11 months old), rates of SVZ cell proliferation were comparable between Sut and wild-type controls, although there was trend towards reduced proliferation in Sut mice (12% and 9% reduction, respectively). To our surprise, rates of cell proliferation in the DG were elevated in both 3- and 11-month-old Sut mice relative to controls (22% and 28% increase, respectively). These results demonstrate that xCT expression plays a role in regulating cellular proliferation in the DG, but not the SVZ of adult mice. Furthermore, unlike previous in vitro studies, our in vivo observations clearly indicate that xCT is not essential for ongoing cellular proliferation

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

    Science.gov (United States)

    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.

  17. Id proteins regulate capillary repair and perivascular cell proliferation following ischemia-reperfusion injury.

    Directory of Open Access Journals (Sweden)

    David Lee

    Full Text Available Acute kidney injury (AKI results in microvascular damage that if not normally repaired, may lead to fibrosis. The Id1 and 3 proteins have a critical role in promoting angiogenesis during development, tumor growth and wound repair by functioning as dominant negative regulators of bHLH transcription factors. The goal of this study was to determine if Id proteins regulate microvascular repair and remodeling and if increased Id1 expression results in decreased capillary loss following AKI. The effect of changes in Id expression in vivo was examined using Id1-/-, Id3RFP/+ (Id1/Id3 KO and Tek (Tie2-rtTA, TRE-lacz/TRE Id1 (TRE Id1 mice with doxycycline inducible endothelial Id1 and β-galactosidase expression. Id1 and 3 were co-localized in endothelial cells in normal adult kidneys and protein levels were increased at day 3 following ischemia-reperfusion injury (IRI and contralateral nephrectomy. Id1/Id3 KO mice had decreased baseline capillary density and pericyte coverage and increased tubular damage following IRI but decreased interstitial cell proliferation and fibrosis compared with WT littermates. No compensatory increase in kidney size occurred in KO mice resulting in increased creatinine compared with WT and TRE Id1 mice. TRE Id1 mice had no capillary rarefaction within 1 week following IRI in comparison with WT littermates. TRE Id1 mice had increased proliferation of PDGFRβ positive interstitial cells and medullary collagen deposition and developed capillary rarefaction and albuminuria at later time points. These differences were associated with increased Angiopoietin 1 (Ang1 and decreased Ang2 expression in TRE Id1 mice. Examination of gene expression in microvascular cells isolated from WT, Id1/Id3 KO and TRE Id1 mice showed increased Ang1 and αSMA in Id1 overexpressing cells and decreased pericyte markers in cells from KO mice. These results suggest that increased Id levels following AKI result in microvascular remodeling associated with

  18. EphA2 is a key effector of the MEK/ERK/RSK pathway regulating glioblastoma cell proliferation.

    Science.gov (United States)

    Hamaoka, Yuho; Negishi, Manabu; Katoh, Hironori

    2016-08-01

    EphA2, a member of the Eph receptor tyrosine kinases, is frequently overexpressed in a variety of malignancies, including glioblastoma, and its expression is correlated with poor prognosis. EphA2 acts as a tumor promoter through a ligand ephrin-independent mechanism, which requires phosphorylation of EphA2 on serine 897 (S897), leading to increased cell migration and invasion. In this study, we show that ligand-independent EphA2 signaling occurs downstream of the MEK/ERK/RSK pathway and mediates epidermal growth factor (EGF)-induced cell proliferation in glioblastoma cells. Suppression of EphA2 expression by long-term exposure to ligand ephrinA1 or EphA2-targeted shRNA inhibited EGF-induced cell proliferation. Stimulation of the cells with EGF induced EphA2 S897 phosphorylation, which was suppressed by MEK and RSK inhibitors, but not by phosphatidylinositol 3-kinase (PI3K) and Akt inhibitors. The RSK inhibitor or RSK2-targeted shRNA also suppressed EGF-induced cell proliferation. Furthermore, overexpression of wild-type EphA2 promoted cell proliferation without EGF stimulation, whereas overexpression of EphA2-S897A mutant suppressed EGF- or RSK2-induced proliferation. Taken together, these results suggest that EphA2 is a key downstream target of the MEK/ERK/RSK signaling pathway in the regulation of glioblastoma cell proliferation. PMID:27132626

  19. Regulation of Trib2 by an E2F1-C/EBPα feedback loop in AML cell proliferation.

    LENUS (Irish Health Repository)

    Rishi, Loveena

    2014-04-10

    The loss of regulation of cell proliferation is a key event in leukemic transformation, and the oncogene tribbles (Trib)2 is emerging as a pivotal target of transcription factors in acute leukemias. Deregulation of the transcription factor E2F1, normally repressed by CCAAT enhancer-binding protein α (C\\/EBPα)-p42, occurs in acute myeloid leukemia (AML), resulting in the perturbation of cell cycle and apoptosis, emphasizing its importance in the molecular pathogenesis of AML. Here we show that E2F family members directly regulate Trib2 in leukemic cells and identify a feedback regulatory loop for E2F1, C\\/EBPα, and Trib2 in AML cell proliferation and survival. Further analyses revealed that E2F1-mediated Trib2 expression was repressed by C\\/EBPα-p42, and in normal granulocyte\\/macrophage progenitor cells, we detect C\\/EBPα bound to the Trib2 promoter. Pharmacological inhibition of the cell cycle or Trib2 knockdown resulted in a block in AML cell proliferation. Our work proposes a novel paradigm whereby E2F1 plays a key role in the regulation of Trib2 expression important for AML cell proliferation control. Importantly, we identify the contribution of dysregulated C\\/EBPα and E2F1 to elevated Trib2 expression and leukemic cell survival, which likely contributes to the initiation and maintenance of AML and may have significant implications for normal and malignant hematopoiesis.

  20. Curcumin inhibits oral squamous cell carcinoma SCC-9 cells proliferation by regulating miR-9 expression

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Can [Department of Occupational Medicine and Environmental Health, School of Public Health, Soochow University, Suzhou 215123 (China); Department of Stomatology, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Wang, Lili; Zhu, Lifang [Department of Stomatology, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Zhang, Chenping, E-mail: zhang_cping@163.com [Department of Head and Neck Tumors, Shanghai Ninth People’s Hospital Affiliated Shanghai JiaoTong University School of Medicine, Shanghai 200011 (China); Zhou, Jianhua [Department of Occupational Medicine and Environmental Health, School of Public Health, Soochow University, Suzhou 215123 (China)

    2014-11-28

    Highlights: • miR-9 expression level was significantly decreased in OSCC tissues. • Curcumin significantly inhibited SCC-9 cells proliferation. • miR-9 mediates the inhibition of SCC-9 proliferation by curcumin. • Curcumin suppresses Wnt/β-catenin signaling in SCC-9 cells. • miR-9 mediates the suppression of Wnt/β-catenin signaling by curcumin. - Abstract: Curcumin, a phytochemical derived from the rhizome of Curcuma longa, has shown anticancer effects against a variety of tumors. In the present study, we investigated the effects of curcumin on the miR-9 expression in oral squamous cell carcinoma (OSCC) and explored the potential relationships between miR-9 and Wnt/β-catenin pathway in curcumin-mediated OSCC inhibition in vitro. As the results shown, the expression levels of miR-9 were significantly lower in clinical OSCC specimens than those in the adjacent non-tumor tissues. Furthermore, our results indicated that curcumin inhibited OSCC cells (SCC-9 cells) proliferation through up-regulating miR-9 expression, and suppressing Wnt/β-catenin signaling by increasing the expression levels of the GSK-3β, phosphorylated GSK-3β and β-catenin, and decreasing the cyclin D1 level. Additionally, the up-regulation of miR-9 by curcumin in SCC-9 cells was significantly inhibited by delivering anti-miR-9 but not control oligonucleotides. Downregulation of miR-9 by anti-miR-9 not only attenuated the growth-suppressive effects of curcumin on SCC-9 cells, but also re-activated Wnt/β-catenin signaling that was inhibited by curcumin. Therefore, our findings would provide a new insight into the use of curcumin against OSCC in future.

  1. Curcumin inhibits oral squamous cell carcinoma SCC-9 cells proliferation by regulating miR-9 expression

    International Nuclear Information System (INIS)

    Highlights: • miR-9 expression level was significantly decreased in OSCC tissues. • Curcumin significantly inhibited SCC-9 cells proliferation. • miR-9 mediates the inhibition of SCC-9 proliferation by curcumin. • Curcumin suppresses Wnt/β-catenin signaling in SCC-9 cells. • miR-9 mediates the suppression of Wnt/β-catenin signaling by curcumin. - Abstract: Curcumin, a phytochemical derived from the rhizome of Curcuma longa, has shown anticancer effects against a variety of tumors. In the present study, we investigated the effects of curcumin on the miR-9 expression in oral squamous cell carcinoma (OSCC) and explored the potential relationships between miR-9 and Wnt/β-catenin pathway in curcumin-mediated OSCC inhibition in vitro. As the results shown, the expression levels of miR-9 were significantly lower in clinical OSCC specimens than those in the adjacent non-tumor tissues. Furthermore, our results indicated that curcumin inhibited OSCC cells (SCC-9 cells) proliferation through up-regulating miR-9 expression, and suppressing Wnt/β-catenin signaling by increasing the expression levels of the GSK-3β, phosphorylated GSK-3β and β-catenin, and decreasing the cyclin D1 level. Additionally, the up-regulation of miR-9 by curcumin in SCC-9 cells was significantly inhibited by delivering anti-miR-9 but not control oligonucleotides. Downregulation of miR-9 by anti-miR-9 not only attenuated the growth-suppressive effects of curcumin on SCC-9 cells, but also re-activated Wnt/β-catenin signaling that was inhibited by curcumin. Therefore, our findings would provide a new insight into the use of curcumin against OSCC in future

  2. LncRNA-uc.167 influences cell proliferation, apoptosis and differentiation of P19 cells by regulating Mef2c.

    Science.gov (United States)

    Song, Guixian; Shen, Yahui; Ruan, Zhongbao; Li, Xing; Chen, Yumei; Yuan, Wei; Ding, Xiangwei; Zhu, Li; Qian, Lingmei

    2016-09-15

    In our previous study we screened thousands of lncRNAs for their relationship with ventricular septal defect. Among these lncRNAs, uc.167 attracted our attention for its high level of conservation and that it was antisense to the Mef2c gene, which encodes myocyte enhancer factor 2C. This study aims to investigate the role of uc.167 during cardiomyocyte maturation in P19 cells induction and possible mechanism. The uc.167 expression level in human heart tissue of ventricular septum defect (VSD) was evaluated by qRT-PCR. The UCSC database was searched to investigate the bioinformatics of uc.167. We constructed overexpression vector of uc.167 and Mef2c. To detect proliferation and apoptosis, we combined cell cycle analysis and CCK8, Hoechst staining, flow cytometry and caspase-3 assays, respectively. The cardiomyogenesis related RNAs (cTnT, GATA4, and Mef2c) and proteins were detected by qRT-PCR and Western blotting. In this study, we found that uc.167 expression was significantly increased in VSD heart tissues. uc.167 is on the opposite strand to the coding gene Mef2c. The expression model of Mef2c and uc.167 showed an opposite correlation in the embryonic development and process of differentiation of P19 cells into cardiomyocytes. Overexpression of uc.167 inhibited proliferation but promoted apoptosis in P19 cells compared with the vector group, and those relative mRNAs and proteins decreased during the differentiation process. Whereas, co-expression of Mef2c and uc.167 can partially reverse the negative effects of uc.167 on proliferation, apoptosis and differentiation. Taken together, our findings suggest that uc.167 contributes to the development potential of VSD and may constitute a potential therapeutic target in this disease. uc.167 influences cell proliferation, apoptosis and differentiation of P19 cell by regulating Mef2c. PMID:27268728

  3. Zeb1 Is a Potential Regulator of Six2 in the Proliferation, Apoptosis and Migration of Metanephric Mesenchyme Cells

    Science.gov (United States)

    Gu, Yuping; Zhao, Ya; Zhou, Yuru; Xie, Yajun; Ju, Pan; Long, Yaoshui; Liu, Jianing; Ni, Dongsheng; Cao, Fen; Lyu, Zhongshi; Mao, Zhaomin; Hao, Jin; Li, Yiman; Wan, Qianya; Kanyomse, Quist; Liu, Yamin; Ren, Die; Ning, Yating; Li, Xiaofeng; Zhou, Qin; Li, Bing

    2016-01-01

    Nephron progenitor cells surround around the ureteric bud tips (UB) and inductively interact with the UB to originate nephrons, the basic units of renal function. This process is determined by the internal balance between self-renewal and consumption of the nephron progenitor cells, which is depending on the complicated regulation networks. It has been reported that Zeb1 regulates the proliferation of mesenchymal cells in mouse embryos. However, the role of Zeb1 in nephrons generation is not clear, especially in metanephric mesenchyme (MM). Here, we detected cell proliferation, apoptosis and migration in MM cells by EdU assay, flow cytometry assay and wound healing assay, respectively. Meanwhile, Western and RT-PCR were used to measure the expression level of Zeb1 and Six2 in MM cells and developing kidney. Besides, the dual-luciferase assay was conducted to study the molecular relationship between Zeb1 and Six2. We found that knock-down of Zeb1 decreased cell proliferation, migration and promoted cell apoptosis in MM cells and Zeb1 overexpression leaded to the opposite data. Western-blot and RT-PCR results showed that knock-down of Zeb1 decreased the expression of Six2 in MM cells and Zeb1 overexpression contributed to the opposite results. Similarly, Zeb1 promoted Six2 promoter reporter activity in luciferase assays. However, double knock-down of Zeb1 and Six2 did not enhance the apoptosis of MM cells compared with control cells. Nevertheless, double silence of Zeb1 and Six2 repressed cell proliferation. In addition, we also found that Zeb1 and Six2 had an identical pattern in distinct developing phases of embryonic kidney. These results indicated that there may exist a complicated regulation network between Six2 and Zeb1. Together, we demonstrate Zeb1 promotes proliferation and apoptosis and inhibits the migration of MM cells, in association with Six2. PMID:27509493

  4. Selective functionalization of nanofiber scaffolds to regulate salivary gland epithelial cell proliferation and polarity.

    Science.gov (United States)

    Cantara, Shraddha I; Soscia, David A; Sequeira, Sharon J; Jean-Gilles, Riffard P; Castracane, James; Larsen, Melinda

    2012-11-01

    Epithelial cell types typically lose apicobasal polarity when cultured on 2D substrates, but apicobasal polarity is required for directional secretion by secretory cells, such as salivary gland acinar cells. We cultured salivary gland epithelial cells on poly(lactic-co-glycolic acid) (PLGA) nanofiber scaffolds that mimic the basement membrane, a specialized extracellular matrix, and examined cell proliferation and apicobasal polarization. Although cells proliferated on nanofibers, chitosan-coated nanofiber scaffolds stimulated proliferation of salivary gland epithelial cells. Although apicobasal cell polarity was promoted by the nanofiber scaffolds relative to flat surfaces, as determined by the apical localization of ZO-1, it was antagonized by the presence of chitosan. Neither salivary gland acinar nor ductal cells fully polarized on the nanofiber scaffolds, as determined by the homogenous membrane distribution of the mature tight junction marker, occludin. However, nanofiber scaffolds chemically functionalized with the basement membrane protein, laminin-111, promoted more mature tight junctions, as determined by apical localization of occludin, but did not affect cell proliferation. To emulate the multifunctional capabilities of the basement membrane, bifunctional PLGA nanofibers were generated. Both acinar and ductal cell lines responded to signals provided by bifunctional scaffolds coupled to chitosan and laminin-111, demonstrating the applicability of such scaffolds for epithelial cell types.

  5. RanBP3 Regulates Melanoma Cell Proliferation via Selective Control of Nuclear Export.

    Science.gov (United States)

    Pathria, Gaurav; Garg, Bhavuk; Wagner, Christine; Garg, Kanika; Gschaider, Melanie; Jalili, Ahmad; Wagner, Stephan N

    2016-01-01

    Chromosome region maintenance 1-mediated nucleocytoplasmic transport has been shown as a potential anticancer target in various malignancies. However, the role of the most characterized chromosome region maintenance 1 cofactor ran binding protein 3 (RanBP3) in cancer cell biology has never been investigated. Utilizing a loss-of-function experimental setting in a vast collection of genetically varied melanoma cell lines, we observed the requirement of RanBP3 in melanoma cell proliferation and survival. Mechanistically, we suggest the reinstatement of transforming growth factor-β (TGF-β)-Smad2/3-p21(Cip1) tumor-suppressor axis as part of the RanBP3 silencing-associated antiproliferative program. Employing extensive nuclear export sequence analyses and immunofluorescence-based protein localization studies, we further present evidence suggesting the requirement of RanBP3 function for the nuclear exit of the weak nuclear export sequence-harboring extracellular signal-regulated kinase protein, although it is dispensable for general CRM1-mediated nuclear export of strong nuclear export sequence-harboring cargoes. Rendering mechanistic support to RanBP3 silencing-mediated apoptosis, consequent to extracellular signal-regulated kinase nuclear entrapment, we observed increased levels of cytoplasmically restricted nonphosphorylated/active proapoptotic Bcl-2-antagonist of cell death (BAD) protein. Last, we present evidence suggesting the frequently activated mitogen-activated protein kinase signaling in melanoma as a potential founding basis for a deregulated post-translational control of RanBP3 activity. Collectively, the presented data suggest RanBP3 as a potential target for therapeutic intervention in human melanoma.

  6. NFAT5 promotes proliferation and migration of lung adenocarcinoma cells in part through regulating AQP5 expression.

    Science.gov (United States)

    Guo, Kai; Jin, Faguang

    2015-09-25

    The osmoregulated transcription factor nuclear factor of activated T-cells 5(NFAT5), has been found to play important roles in the development of many kinds of human cancers, including breast cancer, colon carcinoma, renal cell carcinoma and melanoma. The aim of the present study was to determine whether NFAT5 is involved in the proliferation and migration of lung adenocarcinoma cells. We found that NFAT5 was upregulated in lung adenocarcinoma cells and knockdown of NFAT5 decreased proliferation and migration of the cells, accompanied by a significant reduction in the expression of AQP5. AQP5 was upregulated in lung adenocarcinoma cells and knockdown of AQP5 also inhibited proliferation and migration of the cells as knockdown of NFAT5 did. Moreover, overexpression of NFAT5 promoted proliferation and migration of lung adenocarcinoma cells, accompanied by a significant increase in the expression of AQP5. These results indicate that NFAT5 plays important roles in proliferation and migration of human lung adenocarcinoma cells through regulating AQP5 expression, providing a new therapeutic option for lung adenocarcinoma therapy.

  7. The histone demethylase JMJD1A regulates adrenomedullin-mediated cell proliferation in hepatocellular carcinoma under hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seong-Joon [Research Center, Dongnam Institute of Radiological and Medical Science (DIRAMS), Busan 619-953 (Korea, Republic of); Department of Pharmacy, Pusan National University, Busan 609-735 (Korea, Republic of); Kim, Joong-Gook; Son, Tae Gen; Yi, Joo Mi [Research Center, Dongnam Institute of Radiological and Medical Science (DIRAMS), Busan 619-953 (Korea, Republic of); Kim, Nam Deuk [Department of Pharmacy, Pusan National University, Busan 609-735 (Korea, Republic of); Yang, Kwangmo [Research Center, Dongnam Institute of Radiological and Medical Science (DIRAMS), Busan 619-953 (Korea, Republic of); Department of Radiation Oncology, Dongnam Institute of Radiological and Medical Sciences, Busan 619-953 (Korea, Republic of); Department of Radiation Oncology, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Heo, Kyu, E-mail: khjhk33@gmail.com [Research Center, Dongnam Institute of Radiological and Medical Science (DIRAMS), Busan 619-953 (Korea, Republic of)

    2013-05-17

    Highlights: •Hypoxia stimulates HepG2 and Hep3B cell proliferation. •The JMJD1A and ADM expressions are enhanced by hypoxia in HCCs. •Increased JMJD1A expression reduces a H3K9 di-methylation in the ADM promoter region. •Knock-down of JMJD1A abrogates the hypoxia-induced HepG2 and Hep3B cell growth. -- Abstract: We studied the roles of JMJD1A and its target gene ADM in the growth of hepatocellular carcinomas (HCCs) and breast cancer cells under hypoxic conditions. Hypoxia stimulated HepG2 and Hep3B cell proliferation but had no effect on MDA-MB-231 cell proliferation. Interestingly, the JMJD1A and ADM expressions were enhanced by hypoxia only in HepG2 and Hep3B cells. Our ChIP results showed that hypoxia-induced HepG2 and Hep3B cell proliferation is mediated by JMJD1A upregulation and subsequent decrease in methylation in the ADM promoter region. Furthermore, JMJD1A gene silencing abrogated the hypoxia-induced ADM expression and inhibited HepG2 and Hep3B cell growth. These data suggest that JMJD1A might function as a proliferation regulator in some cancer cell types.

  8. Glycogen synthase kinase 3 beta positively regulates Notch signaling in vascular smooth muscle cells: role in cell proliferation and survival.

    Science.gov (United States)

    Guha, Shaunta; Cullen, John P; Morrow, David; Colombo, Alberto; Lally, Caitríona; Walls, Dermot; Redmond, Eileen M; Cahill, Paul A

    2011-09-01

    The role of glycogen synthase kinase 3 beta (GSK-3β) in modulating Notch control of vascular smooth muscle cell (vSMC) growth (proliferation and apoptosis) was examined in vitro under varying conditions of cyclic strain and validated in vivo following changes in medial tension and stress. Modulation of GSK-3β in vSMC following ectopic expression of constitutively active GSK-3β, siRNA knockdown and pharmacological inhibition with SB-216763 demonstrated that GSK-3β positively regulates Notch intracellular domain expression, CBF-1/RBP-Jκ transactivation and downstream target gene mRNA levels, while concomitantly promoting vSMC proliferation and inhibiting apoptosis. In contrast, inhibition of GSK-3β attenuated Notch signaling and decreased vSMC proliferation and survival. Exposure of vSMC to cyclic strain environments in vitro using both a Flexercell™ Tension system and a novel Sylgard™ phantom vessel following bare metal stent implantation revealed that cyclic strain inhibits GSK-3β activity independent of p42/p44 MAPK and p38 activation concomitant with reduced Notch signaling and decreased vSMC proliferation and survival. Exposure of vSMC to changes in medial strain microenvironments in vivo following carotid artery ligation revealed that enhanced GSK-3β activity was predominantly localized to medial and neointimal vSMC concomitant with increased Notch signaling, proliferating nuclear antigen and decreased Bax expression, respectively, as vascular remodeling progressed. GSK-3β is an important modulator of Notch signaling leading to altered vSMC cell growth where low strain/tension microenvironments prevail.

  9. Variability of doublecortin-associated dendrite maturation in adult hippocampal neurogenesis is independent of the regulation of precursor cell proliferation

    Directory of Open Access Journals (Sweden)

    Jessberger Sebastian

    2006-11-01

    Full Text Available Abstract Background In the course of adult hippocampal neurogenesis most regulation takes place during the phase of doublecortin (DCX expression, either as pro-proliferative effect on precursor cells or as survival-promoting effect on postmitotic cells. We here obtained quantitative data about the proliferative population and the dynamics of postmitotic dendrite development during the period of DCX expression. The question was, whether any indication could be obtained that the initiation of dendrite development is timely bound to the exit from the cell cycle. Alternatively, the temporal course of morphological maturation might be subject to additional regulatory events. Results We found that (1 20% of the DCX population were precursor cells in cell cycle, whereas more than 70% were postmitotic, (2 the time span until newborn cells had reached the most mature stage associated with DCX expression varied between 3 days and several weeks, (3 positive or negative regulation of precursor cell proliferation did not alter the pattern and dynamics of dendrite development. Dendrite maturation was largely independent of close contacts to astrocytes. Conclusion These data imply that dendrite maturation of immature neurons is initiated at varying times after cell cycle exit, is variable in duration, and is controlled independently of the regulation of precursor cell proliferation. We conclude that in addition to the major regulatory events in cell proliferation and selective survival, additional micro-regulatory events influence the course of adult hippocampal neurogenesis.

  10. IL-27 inhibits lymphatic endothelial cell proliferation by STAT1-regulated gene expression

    DEFF Research Database (Denmark)

    Nielsen, Sebastian Rune; Hammer, Troels; Gibson, Josefine;

    2013-01-01

    OBJECTIVE: IL-27 belongs to the IL-12 family of cytokines and is recognized for its role in Th cell differentiation and as an inhibitor of tumor-angiogenesis. The purpose of this study was to investigate the effect of IL-27 on proliferation of lymphatic endothelial cells to gain insight into the ...

  11. Regulation of deleted in liver cancer-1 gene domains on the proliferation of human colon cancer HT29 cell

    Institute of Scientific and Technical Information of China (English)

    吴平平

    2013-01-01

    Objective To study the role of deleted in liver cancer-1(DLC-1) gene main domains on the regulation of hu-man colon cancer HT29 cell proliferation. Methods Subcloning recombinant plasmid vectors with Rho GTPase activating protein(RhoGAP),sterile alpha motif(SAM)

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

    DEFF Research Database (Denmark)

    Piunti, Andrea; Rossi, Alessandra; Cerutti, Aurora;

    2014-01-01

    The ability of PRC1 and PRC2 to promote proliferation is a main feature that links polycomb (PcG) activity to cancer. PcGs silence the expression of the tumour suppressor locus Ink4a/Arf, whose products positively regulate pRb and p53 functions. Enhanced PcG activity is a frequent feature of huma...

  13. Regulation of pancreatic beta-cell mass and proliferation by SOCS-3

    DEFF Research Database (Denmark)

    Lindberg, K; Rønn, S G; Tornehave, D;

    2005-01-01

    Growth hormone and prolactin are important growth factors for pancreatic beta-cells. The effects exerted by these hormones on proliferation and on insulin synthesis and secretion in beta-cells are largely mediated through the Janus kinase (JAK)/signal transducer and activator of transcription (STAT......) signaling pathway. Suppressors of cytokine signaling (SOCS) proteins are specific inhibitors of the JAK/STAT pathway acting through a negative-feedback loop. To investigate in vivo effects of SOCS-3 in growth hormone (GH)/prolactin signaling in beta-cells we generated transgenic mice with beta......-cell-specific overexpression of SOCS-3. The relative beta-cell proliferation and volume in the mice were measured by morphometry. Beta-cell volume of transgenic female mice was reduced by over 30% compared with beta-cell volume in wild-type female mice. Stimulation of transgenic islets in vitro with GH showed a reduced...

  14. Epigallocatechin gallate inhibits the proliferation of colorectal cancer cells by regulating Notch signaling

    Directory of Open Access Journals (Sweden)

    Jin H

    2013-03-01

    Full Text Available Heiying Jin,1,* Wei Gong,2,* Chunxia Zhang,1,* Shuiming Wang1 1National Center of Colorectal Surgery, the Third Affiliated Hospital of Nanjing University of Traditional Chinese Medicine, Nanjing, People’s Republic of China; 2Department of Surgery, Jiangyin Hospital of Traditional Chinese Medicine, Jiangsu, People's Republic of China*These authors contributed equally to this workAims: To explore the inhibitory effects of epigallocatechin gallate (EGCG on the proliferation of colorectal cancer cells and on the gene expression of Notch signaling.Methods: The colorectal cancer cells and orthotopic colorectal cancer transplant model were treated with EGCG, and MTT assay was used to test the inhibitory role of EGCG in the proliferation of colorectal cancer cells. Results: MTT assay indicated that EGCG inhibited the proliferation of these four cell lines when the time and concentration increased, and EGCG enhanced the apoptotic rate of these four cell lines. The dosage was positively correlated to the apoptotic rate, and EGCG inhibited the proliferation of colorectal cancer cells by influencing cell cycle. In-vivo study suggested that on the seventh day, the volume of tumors reduced after administrating with 5, 10 and 20 mg/kg of EGCG. At the twenty-eighth day, the volume of tumors was significantly different in three EGCG treatment groups as compared to the control group (P < 0.05, and TUNEL assay indicated that the apoptosis of cancer cells in EGCG treated groups was markedly higher than that in the control group (P < 0.05. In these cell lines, the expressions of HES1 and Notch2 in EGCG treated groups were remarkably lower than that in the control group (P < 0.05. The expression of JAG1 decreased in SW480 cells (P = 0.019, HT-29 cells and HCT-8 cells, but increased in LoVo cells at mRNA level. The expression of Notch1 was upregulated in these four cell lines, but its expression was significantly upregulated only in LoVo and SW480 cells (P < 0

  15. IL-1β-induced, matrix metalloproteinase-3-regulated proliferation of embryonic stem cell-derived odontoblastic cells is mediated by the Wnt5 signaling pathway

    International Nuclear Information System (INIS)

    We previously established a method for differentiating induced pluripotent stem cells and embryonic stem (ES) cells into α2 integrin-positive odontoblast-like cells. We also reported that interleukin (IL)-1β induces matrix metalloproteinase (MMP)-3-regulated cell proliferation and suppresses apoptosis in these cells, suggesting that MMP-3 plays a potentially unique physiological role in the regeneration of odontoblast-like cells. Here, we examined whether up-regulation of MMP-3 activity by IL-1β was mediated by Wnt signaling and led to increased proliferation of odontoblast-like cells. IL-1β increased mRNA and protein levels of Wnt5a, Wnt5b and the Wnt receptor Lrp5. Exogenous Wnt5a and Wnt5b were found to increase MMP-3 mRNA, protein and activity, and interestingly the rate of proliferation in these cells. Treatment with siRNAs against Wnt5a, Wnt5b and Lrp5 suppressed the IL-1β-induced increase in MMP-3 expression and suppressed cell proliferation, an effect rescued by application of exogenous Wnt5. These results demonstrate the sequential involvement of Wnt5, Lrp5 and MMP-3 in effecting IL-1β-induced proliferation of ES cell-derived odontoblast-like cells. - Highlights: • IL-1β induces Wnt5, Lrp5/Fzd9 and MMP-3 in ES cell-derived odontoblast-like cells. • IL-1β-induced Wnt5 expression results in increased cell proliferation. • Exogenous Wnt5 increases MMP-3 activity and cell proliferation. • Exogenous Wnt5 rescues IL-1β-driven proliferation with anti-Wnt5 siRNA suppression. • IL-1β-induced cell proliferation involves Wnt5, Lrp5, and MMP-3 sequentially

  16. IL-1β-induced, matrix metalloproteinase-3-regulated proliferation of embryonic stem cell-derived odontoblastic cells is mediated by the Wnt5 signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki; Kawai, Rie [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan)

    2014-10-15

    We previously established a method for differentiating induced pluripotent stem cells and embryonic stem (ES) cells into α2 integrin-positive odontoblast-like cells. We also reported that interleukin (IL)-1β induces matrix metalloproteinase (MMP)-3-regulated cell proliferation and suppresses apoptosis in these cells, suggesting that MMP-3 plays a potentially unique physiological role in the regeneration of odontoblast-like cells. Here, we examined whether up-regulation of MMP-3 activity by IL-1β was mediated by Wnt signaling and led to increased proliferation of odontoblast-like cells. IL-1β increased mRNA and protein levels of Wnt5a, Wnt5b and the Wnt receptor Lrp5. Exogenous Wnt5a and Wnt5b were found to increase MMP-3 mRNA, protein and activity, and interestingly the rate of proliferation in these cells. Treatment with siRNAs against Wnt5a, Wnt5b and Lrp5 suppressed the IL-1β-induced increase in MMP-3 expression and suppressed cell proliferation, an effect rescued by application of exogenous Wnt5. These results demonstrate the sequential involvement of Wnt5, Lrp5 and MMP-3 in effecting IL-1β-induced proliferation of ES cell-derived odontoblast-like cells. - Highlights: • IL-1β induces Wnt5, Lrp5/Fzd9 and MMP-3 in ES cell-derived odontoblast-like cells. • IL-1β-induced Wnt5 expression results in increased cell proliferation. • Exogenous Wnt5 increases MMP-3 activity and cell proliferation. • Exogenous Wnt5 rescues IL-1β-driven proliferation with anti-Wnt5 siRNA suppression. • IL-1β-induced cell proliferation involves Wnt5, Lrp5, and MMP-3 sequentially.

  17. Possible mechanism for the regulation of glucose on proliferation, inhibition and apoptosis of colon cancer cells induced by sodium butyrate

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To study the effect of glucose on sodium butyrateinduced proliferation inhibition and apoptosis in HT-29 cell line, and explored its possible mechanisms.METHODS: HT-29 cells were grown in RPMI-1640 medium supplemented with 10% fetal calf serum, and were allowed to adhere for 24 h, and then replaced with experimental medium. Cell survival rates were detected by MTT assay. Apoptosis was detected by TUNEL assay. Glucose transport protein 1 (GLUT1) and monocarboxylate transporter 1 (MCT1) mRNA expression was detected by RT-PCR.RESULTS: Low concentration of glucose induced apoptosis and regulated proliferation in HT-29 cell line, and glucose can obviously inhibit the effect of proliferation inhibition and apoptosis induced by sodium butyrate. Glucose also down-regulated the expression of MCT1mRNA (0.28 ± 0.07 vs 0.19 ± 0.10, P < 0.05), and decreased the expression of GLUT1mRNA slightly (0.18 ± 0.04 vs 0.13 ± 0.03, P < 0.05).CONCLUSION: Glucose can regulate the effect of proliferation inhibition and apoptosis induced by sodium butyrate and this influence may be associated with the intracellular concentration of glucose and sodium butyrate.

  18. MiR-21 up-regulation mediates glioblastoma cancer stem cells apoptosis and proliferation by targeting FASLG.

    Science.gov (United States)

    Shang, Chao; Guo, Yan; Hong, Yang; Liu, Yun-hui; Xue, Yi-xue

    2015-03-01

    To investigate whether miR-21 can affect the apoptosis and proliferation of glioblastoma cancer stem cells (GSCs) from down-regulating FASLG. The expression of miRNA-21 was detected by quantitative real-time PCR in normal brain tissue and glioblastoma samples, and the changes of miRNA-21 expression between GSCs and non-GSCs were also detected. The apoptosis and proliferation ability of miR-21 in GSCs were analyzed by MTT and flow cytometry assay after anti-miR-21 transfection. For the regulation mechanism analysis of miR-21, TargetScan, PicTar and microRNA were selected to predict some potential target genes of miR-21. The predicted gene was identified to be the direct and specific target gene of miR-21 by luciferase activities assay and western blot. RNA interference technology was used to confirm the apoptosis and proliferation effects of miR-21 were directly induced by FASLG. The expression of miR-21 increased significantly in glioblastoma contrast to normal brain tissue, and miR-21 up-regulated in GSCs remarkably. The proliferation of GSCs cell could be inhibited with high-expression of miR-21 and this effect could be restored by miR-21 knocked down. Mechanism analysis revealed that FASLG was a specific and direct target gene of miR-21. The advanced effects of anti-miR-21 on GSCs apoptosis and proliferation were mediated by expression of silenced FASLG. In summary, aberrantly expressed miR-21 regulates GSCs apoptosis and proliferation partly through directly down-regulating FASLG protein expression in GSCs and this might offer a new potential therapeutic stratagem for glioblastoma. PMID:25394756

  19. UV Damage-Induced Phosphorylation of HBO1 Triggers CRL4DDB2-Mediated Degradation To Regulate Cell Proliferation.

    Science.gov (United States)

    Matsunuma, Ryoichi; Niida, Hiroyuki; Ohhata, Tatsuya; Kitagawa, Kyoko; Sakai, Satoshi; Uchida, Chiharu; Shiotani, Bunsyo; Matsumoto, Masaki; Nakayama, Keiichi I; Ogura, Hiroyuki; Shiiya, Norihiko; Kitagawa, Masatoshi

    2015-11-16

    Histone acetyltransferase binding to ORC-1 (HBO1) is a critically important histone acetyltransferase for forming the prereplicative complex (pre-RC) at the replication origin. Pre-RC formation is completed by loading of the MCM2-7 heterohexameric complex, which functions as a helicase in DNA replication. HBO1 recruited to the replication origin by CDT1 acetylates histone H4 to relax the chromatin conformation and facilitates loading of the MCM complex onto replication origins. However, the acetylation status and mechanism of regulation of histone H3 at replication origins remain elusive. HBO1 positively regulates cell proliferation under normal cell growth conditions. Whether HBO1 regulates proliferation in response to DNA damage is poorly understood. In this study, we demonstrated that HBO1 was degraded after DNA damage to suppress cell proliferation. Ser50 and Ser53 of HBO1 were phosphorylated in an ATM/ATR DNA damage sensor-dependent manner after UV treatment. ATM/ATR-dependently phosphorylated HBO1 preferentially interacted with DDB2 and was ubiquitylated by CRL4(DDB2). Replacement of endogenous HBO1 in Ser50/53Ala mutants maintained acetylation of histone H3K14 and impaired cell cycle regulation in response to UV irradiation. Our findings demonstrate that HBO1 is one of the targets in the DNA damage checkpoint. These results show that ubiquitin-dependent control of the HBO1 protein contributes to cell survival during UV irradiation.

  20. Hypoxic stress up-regulates Kir2.1 expression and facilitates cell proliferation in brain capillary endothelial cells.

    Science.gov (United States)

    Yamamura, Hideto; Suzuki, Yoshiaki; Yamamura, Hisao; Asai, Kiyofumi; Imaizumi, Yuji

    2016-08-01

    The blood-brain barrier (BBB) is mainly composed of brain capillary endothelial cells (BCECs), astrocytes and pericytes. Brain ischemia causes hypoxic encephalopathy and damages BBB. However, it remains still unclear how hypoxia affects BCECs. In the present study, t-BBEC117 cells, an immortalized bovine brain endothelial cell line, were cultured under hypoxic conditions at 4-5% oxygen for 72 h. This hypoxic stress caused hyperpolarization of resting membrane potential. Patch-clamp recordings revealed a marked increase in Ba(2+)-sensitive inward rectifier K(+) current in t-BBEC117 cells after hypoxic culture. Western blot and real-time PCR analyses showed that Kir2.1 expression was significantly up-regulated at protein level but not at mRNA level after the hypoxic culture. Ca(2+) imaging study revealed that the hypoxic stress enhanced store-operated Ca(2+) (SOC) entry, which was significantly reduced in the presence of 100 μM Ba(2+). On the other hand, the expression of SOC channels such as Orai1, Orai2, and transient receptor potential channels was not affected by hypoxic stress. MTT assay showed that the hypoxic stress significantly enhanced t-BBEC117 cell proliferation, which was inhibited by approximately 60% in the presence of 100 μM Ba(2+). We first show here that moderate cellular stress by cultivation under hypoxic conditions hyperpolarizes membrane potential via the up-regulation of functional Kir2.1 expression and presumably enhances Ca(2+) entry, resulting in the facilitation of BCEC proliferation. These findings suggest potential roles of Kir2.1 expression in functional changes of BCECs in BBB following ischemia. PMID:27235552

  1. Pyruvate kinase isoenzyme M2 is a glycolytic sensor differentially regulating cell proliferation, cell size and apoptotic cell death dependent on glucose supply

    Energy Technology Data Exchange (ETDEWEB)

    Spoden, Gilles A. [Department of Cell Metabolism and Differentiation, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, Rennweg 10, 6020 Innsbruck (Austria); Tumorvirology Research Group, Tyrolean Cancer Research Institute, Medical University Innsbruck, Innrain 66, 6020 Innsbruck (Austria); Rostek, Ursula; Lechner, Stefan; Mitterberger, Maria [Department of Cell Metabolism and Differentiation, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, Rennweg 10, 6020 Innsbruck (Austria); Mazurek, Sybille [Department for Biochemistry and Endocrinology, Veterinary Faculty, University of Giessen, 35392 Giessen (Germany); ScheBo Biotech AG, Netanyastrasse 3, 35394 Giessen (Germany); Zwerschke, Werner, E-mail: werner.zwerschke@oeaw.ac.at [Department of Cell Metabolism and Differentiation, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, Rennweg 10, 6020 Innsbruck (Austria); Tumorvirology Research Group, Tyrolean Cancer Research Institute, Medical University Innsbruck, Innrain 66, 6020 Innsbruck (Austria)

    2009-10-01

    The glycolytic key regulator pyruvate kinase M2 (M2-PK or PKM2) can switch between a highly active tetrameric and an inactive dimeric form. The transition between the two conformations regulates the glycolytic flux in tumor cells. We developed specific M2-PK-binding peptide aptamers which inhibit M2-PK, but not the 96% homologous M1-PK isoenzyme. In this study we demonstrate that, at normal blood glucose concentrations, peptide aptamer-mediated inhibition of M2-PK induces a significant decrease of the population doubling (PDL rate) and cell proliferation rate as well as an increase in cell size, whereas under glucose restriction an increase in PDL and cell proliferation rates but a decrease in cell size was observed. Moreover, M2-PK inhibition rescues cells from glucose starvation-induced apoptotic cell death by increasing the metabolic activity. These findings suggest that M2-PK is a metabolic sensor which regulates cell proliferation, cell growth and apoptotic cell death in a glucose supply-dependent manner.

  2. p62 Regulates the Proliferation of Molecular Apocrine Breast Cancer Cells

    Science.gov (United States)

    Nozaki, Fumi; Hirotani, Yukari; Nakanishi, Yoko; Yamaguchi, Hiromi; Nishimaki, Haruna; Noda, Hiroko; Tang, Xiaoyan; Yamamoto, Hisae; Suzuki, Atsuko; Seki, Toshimi; Masuda, Shinobu

    2016-01-01

    p62, also called sequestosome 1 (SQSTM1), is a multifunctional signaling molecule that affects cell proliferation. Recently, we found accumulation of p62 in apocrine carcinoma of the breast, however, the biological role of p62 expression in apocrine carcinoma still remains unclear. To investigate whether p62 might contribute to tumor cell proliferation in apocrine carcinomas, we used the MDA-MB-453 (androgen receptor-positive, HER2-type) and MFM223 (androgen receptor-positive, triple-negative type) breast cancer cell lines as models of molecular apocrine carcinoma. Both MDA-MB-453 and MFM223 showed strong and d high p62 protein expression than MCF7 cells (androgen receptor-negative, luminal A type). Knockdown of p62 resulted in significant reduction of the cell proliferative activity in both MDA-MB-453 (P<0.01) and MFM223 (P<0.05). In conclusion, p62 could contribute to cell proliferation and represent a therapeutic target in apocrine carcinoma.

  3. Down regulation of miR-203 in radiation-induced thymic lymphoma promoted cells proliferation and inhibited apoptosis%Down regulation of miR-203in radiation-induced thymic lymphoma promoted cells proliferation and inhibited apoptosis

    Institute of Scientific and Technical Information of China (English)

    Zhang Chaoxiong; Zhang Mingjian; Gao Fu; Zhou Chuanfeng; Zhang Pei; Cai Jianming; Liu Cong

    2015-01-01

    Objective To investigate the role of miR-203 in radiation-induced thymic lymphoma (RITL).Methods A 60Co irradiator was used for total-body irradiation.MicroRNAs(miRNAs) level was assayed by qRT-PCR.Cell proliferation was assayed by MTT assay.Cell apoptosis was examined by fluorescence activated cell sorter (FACS).Dual luciferase reporter assay system was used to detect the 3'UTR reporter.Results MiR-203 was down-regulated in RITL tissues.Overexpression of miR-203 strongly inhibited the proliferation of both NIH3T3 cells and EL4 cells and vice versa.MiR-203 inhibited cells proliferation and induced apoptosis via TANK-binding kinase (TBK1),SLUG (SNAI2) and Cyclin D1 (CCND1).Conclusions Radiation down-regulated the level of miR-203 in thymic,which promoted radiation-induced thymic lymphoma by targeting TBK1,SNAI2 and CCND1.

  4. Cullin 3 targets methionine adenosyltransferase IIα for ubiquitylation-mediated degradation and regulates colorectal cancer cell proliferation.

    Science.gov (United States)

    Wang, Jian; Zhu, Zi-Hua; Yang, Hong-Bin; Zhang, Ye; Zhao, Xiang-Ning; Zhang, Min; Liu, Ying-Bin; Xu, Ying-Ying; Lei, Qun-Ying

    2016-07-01

    Cullin 3 (CUL3) serves as a scaffold protein and assembles a large number of ubiquitin ligase complexes. It is involved in multiple cellular processes and plays a potential role in tumor development and progression. In this study, we demonstrate that CUL3 targets methionine adenosyltransferase IIα (MAT IIα) and promotes its proteasomal degradation through the ubiquitylation-mediated pathway. MAT IIα is a key enzyme in methionine metabolism and is associated with uncontrolled cell proliferation in cancer. We presently found that CUL3 down-regulation could rescue folate deprivation-induced MAT IIα exhaustion and growth arrest in colorectal cancer (CRC) cells. Further results from human CRC samples display an inverse correlation between CUL3 and MAT IIα protein levels. Our observations reveal a novel role of CUL3 in regulating cell proliferation by controlling the stability of MAT IIα. PMID:27213918

  5. Cullin 3 targets methionine adenosyltransferase IIα for ubiquitylation-mediated degradation and regulates colorectal cancer cell proliferation.

    Science.gov (United States)

    Wang, Jian; Zhu, Zi-Hua; Yang, Hong-Bin; Zhang, Ye; Zhao, Xiang-Ning; Zhang, Min; Liu, Ying-Bin; Xu, Ying-Ying; Lei, Qun-Ying

    2016-07-01

    Cullin 3 (CUL3) serves as a scaffold protein and assembles a large number of ubiquitin ligase complexes. It is involved in multiple cellular processes and plays a potential role in tumor development and progression. In this study, we demonstrate that CUL3 targets methionine adenosyltransferase IIα (MAT IIα) and promotes its proteasomal degradation through the ubiquitylation-mediated pathway. MAT IIα is a key enzyme in methionine metabolism and is associated with uncontrolled cell proliferation in cancer. We presently found that CUL3 down-regulation could rescue folate deprivation-induced MAT IIα exhaustion and growth arrest in colorectal cancer (CRC) cells. Further results from human CRC samples display an inverse correlation between CUL3 and MAT IIα protein levels. Our observations reveal a novel role of CUL3 in regulating cell proliferation by controlling the stability of MAT IIα.

  6. MicroRNA-130b targets Fmr1 and regulates embryonic neural progenitor cell proliferation and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Xi [State Key Laboratory of Food Science and Technology, College of Life Sciences and Food Engineering, Nanchang University, Nanchang 330047 (China); Zhang, Kunshan [Department of Regenerative Medicine, Stem Cell Center, Tongji University School of Medicine, Shanghai 200092 (China); Wang, Yanlu; Wang, Junbang; Cui, Yaru [State Key Laboratory of Food Science and Technology, College of Life Sciences and Food Engineering, Nanchang University, Nanchang 330047 (China); Li, Siguang, E-mail: siguangli@163.com [Department of Regenerative Medicine, Stem Cell Center, Tongji University School of Medicine, Shanghai 200092 (China); Luo, Yuping, E-mail: luoyuping@163.com [State Key Laboratory of Food Science and Technology, College of Life Sciences and Food Engineering, Nanchang University, Nanchang 330047 (China)

    2013-10-04

    Highlights: •We found that the 3′ UTR of the Fmr1 mRNA is a target of miR-130b. •MiR-130b suppresses the expression of Fmr1 in mouse embryonic stem cell. •MiR-130b alters the proliferation of mouse embryonic stem cell. •MiR-130b alters fate specification of mouse embryonic stem cell. -- Abstract: Fragile X syndrome, one of the most common forms of inherited mental retardation, is caused by expansion of the CGG repeat in the 5′-untranslated region of the X-linked Fmr1 gene, which results in transcriptional silencing and loss of expression of its encoded protein FMRP. The loss of FMRP increases proliferation and alters fate specification in adult neural progenitor cells (aNPCs). However, little is known about Fmr1 mRNA regulation at the transcriptional and post-transcriptional levels. In the present study, we report that miR-130b regulated Fmr1 expression by directly targeting its 3′-untranslated region (3′ UTR). Up-regulation of miR-130b in mouse embryonic neural progenitor cells (eNPCs) decreased Fmr1 expression, markedly increased eNPC proliferation and altered the differentiation tendency of eNPCs, suggesting that antagonizing miR-130b may be a new therapeutic entry point for treating Fragile X syndrome.

  7. MicroRNA-130b targets Fmr1 and regulates embryonic neural progenitor cell proliferation and differentiation

    International Nuclear Information System (INIS)

    Highlights: •We found that the 3′ UTR of the Fmr1 mRNA is a target of miR-130b. •MiR-130b suppresses the expression of Fmr1 in mouse embryonic stem cell. •MiR-130b alters the proliferation of mouse embryonic stem cell. •MiR-130b alters fate specification of mouse embryonic stem cell. -- Abstract: Fragile X syndrome, one of the most common forms of inherited mental retardation, is caused by expansion of the CGG repeat in the 5′-untranslated region of the X-linked Fmr1 gene, which results in transcriptional silencing and loss of expression of its encoded protein FMRP. The loss of FMRP increases proliferation and alters fate specification in adult neural progenitor cells (aNPCs). However, little is known about Fmr1 mRNA regulation at the transcriptional and post-transcriptional levels. In the present study, we report that miR-130b regulated Fmr1 expression by directly targeting its 3′-untranslated region (3′ UTR). Up-regulation of miR-130b in mouse embryonic neural progenitor cells (eNPCs) decreased Fmr1 expression, markedly increased eNPC proliferation and altered the differentiation tendency of eNPCs, suggesting that antagonizing miR-130b may be a new therapeutic entry point for treating Fragile X syndrome

  8. A planarian p53 homolog regulates proliferation and self-renewal in adult stem cell lineages.

    Science.gov (United States)

    Pearson, Bret J; Sánchez Alvarado, Alejandro

    2010-01-01

    The functions of adult stem cells and tumor suppressor genes are known to intersect. However, when and how tumor suppressors function in the lineages produced by adult stem cells is unknown. With a large population of stem cells that can be manipulated and studied in vivo, the freshwater planarian is an ideal system with which to investigate these questions. Here, we focus on the tumor suppressor p53, homologs of which have no known role in stem cell biology in any invertebrate examined thus far. Planaria have a single p53 family member, Smed-p53, which is predominantly expressed in newly made stem cell progeny. When Smed-p53 is targeted by RNAi, the stem cell population increases at the expense of progeny, resulting in hyper-proliferation. However, ultimately the stem cell population fails to self-renew. Our results suggest that prior to the vertebrates, an ancestral p53-like molecule already had functions in stem cell proliferation control and self-renewal. PMID:20040488

  9. Role of Baicalein in the regulation of proliferation and apoptosis in human myeloma RPMI8226 cells

    Institute of Scientific and Technical Information of China (English)

    LI Qiu-bai; YOU Yong; CHEN Zhi-chao; L(U) Jian; SHAO Jing; ZOU Ping

    2006-01-01

    @@ Multiple myeloma (MM) is a uniformly fatal disease characterized by a clonal proliferation of neoplastic plasma cells in the bone marrow and is the second most commol hematological malignancy.1 At present, a cure for multiple myeloma has not been achieved with chemotherapeutic regimen, and many patients die of drug-resistant disease. Thus, the development of new effective anticancer agents to treat both early and advanced MM seems to be an attractive perspective.

  10. Regulation of the human SLC25A20 expression by peroxisome proliferator-activated receptor alpha in human hepatoblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Tachibana, Keisuke, E-mail: nya@phs.osaka-u.ac.jp [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Takeuchi, Kentaro; Inada, Hirohiko [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Yamasaki, Daisuke [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ishimoto, Kenji [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Tanaka, Toshiya; Hamakubo, Takao; Sakai, Juro; Kodama, Tatsuhiko [Laboratory for System Biology and Medicine, Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8904 (Japan); Doi, Takefumi [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2009-11-20

    Solute carrier family 25, member 20 (SLC25A20) is a key molecule that transfers acylcarnitine esters in exchange for free carnitine across the mitochondrial membrane in the mitochondrial {beta}-oxidation. The peroxisome proliferator-activated receptor alpha (PPAR{alpha}) is a ligand-activated transcription factor that plays an important role in the regulation of {beta}-oxidation. We previously established tetracycline-regulated human cell line that can be induced to express PPAR{alpha} and found that PPAR{alpha} induces the SLC25A20 expression. In this study, we analyzed the promoter region of the human slc25a20 gene and showed that PPAR{alpha} regulates the expression of human SLC25A20 via the peroxisome proliferator responsive element.

  11. Dehydroepiandrosterone inhibits cell proliferation and improves viability by regulating S phase and mitochondrial permeability in primary rat Leydig cells

    Science.gov (United States)

    LIU, LIN; WANG, DIAN; LI, LONGLONG; DING, XIAO; MA, HAITIAN

    2016-01-01

    Dehydroepiandrosterone (DHEA) is widely used as a nutritional supplement and exhibits putative anti-aging properties. However, the molecular basis of the actions of DHEA, particularly on the biological characteristics of target cells, remain unclear. The aim of the current study was to investigate the effects of DHEA on cell viability, cell proliferation, cell cycle and mitochondrial function in primary rat Leydig cells. Adult Leydig cells were purified by Percoll gradient centrifugation, and cell proliferation was detected using a Click-iT® EdU Assay kit and cell cycle assessment performed using flow cytometry. Mitochondrial membrane potential was detected using JC-1 staining assay. The results of the current study demonstrate that DHEA decreased cell proliferation in a dose-dependent manner, whereas it improved cell viability in a time-dependent and dose-dependent manner. Flow cytometry analysis demonstrated that DHEA treatment increased the S phase cell population and decreased the G2/M cell population. Cyclin A and CDK2 mRNA levels were decreased in primary rat Leydig cells following DHEA treatment. DHEA treatment decreased the transmembrane electrical gradient in primary Leydig cells, whereas treatment significantly increased succinate dehydrogenase activity. These results indicated that DHEA inhibits primary rat Leydig cell proliferation by decreasing cyclin mRNA level, whereas it improves cells viability by modulating the permeability of the mitochondrial membrane and succinate dehydrogenase activity. These findings may demonstrate an important molecular mechanism by which DHEA activity is mediated. PMID:27220727

  12. Intrinsic protein flexibility in regulation of cell proliferation: advantages for signaling and opportunities for novel therapeutics.

    Science.gov (United States)

    Follis, Ariele Viacava; Galea, Charles A; Kriwacki, Richard W

    2012-01-01

    It is now widely recognized that intrinsically disordered (or unstructured) proteins (IDPs, or IUPs) are found in organisms from all kingdoms of life. In eukaryotes, IDPs are highly abundant and perform a wide range of biological functions, including regulation and signaling. Despite increased interest in understanding the structural biology of IDPs, questions remain regarding the mechanisms through which disordered proteins perform their biological function(s). In other words, what are the relationships between disorder and function for IDPs? Several excellent reviews have recently been published that discuss the structural properties of IDPs.1-3 Here, we discuss two IDP systems which illustrate features of dynamic complexes. In the first section, we discuss two IDPs, p21 and p27, which regulate the mammalian cell division cycle by inhibiting cyclin-dependent kinases (Cdks). In the second section, we discuss recent results from Follis, Hammoudeh, Metallo and coworkers demonstrating that the IDP Myc can be bound and inhibited by small molecules through formation of dynamic complexes. Previous studies have shown that polypeptide segments of p21 and p27 are partially folded in isolation and fold further upon binding their biological targets. Interestingly, some portions of p27 which bind to and inhibit Cdk2/cyclin A remain flexible in the bound complex. This residual flexibility allows otherwise buried tyrosine residues within p27 to be phosphorylated by nonreceptor tyrosine kinases (NRTKs). Tyrosine phosphorylation relieves kinase inhibition, triggering Cdk2-mediated phosphorylation of a threonine residue within the flexible C-terminus of p27. This, in turn, marks p27 for ubiquitination and proteasomal degradation, unleashing full Cdk2 activity which drives cell cycle progression. p27, thus, constitutes a conduit for transmission of proliferative signals via posttranslational modifications. Importantly, activation of the p27 signaling conduit by oncogenic NRTKs

  13. PSGL-1 regulates the migration and proliferation of CD8(+) T cells under homeostatic conditions.

    Science.gov (United States)

    Veerman, Krystle M; Carlow, Douglas A; Shanina, Iryna; Priatel, John J; Horwitz, Marc S; Ziltener, Hermann J

    2012-02-15

    P-selectin glycoprotein ligand-1 (PSGL-1), a heavily glycosylated sialomucin expressed on most leukocytes, has dual function as a selectin ligand for leukocyte rolling on vascular selectins expressed in inflammation and as a facilitator of resting T cell homing into lymphoid organs. In this article, we document disturbances in T cell homeostasis present in PSGL-1(null) mice. Naive CD4(+) and CD8(+) T cell frequencies were profoundly reduced in blood, whereas T cell numbers in lymph nodes and spleen were at or near normal levels. Although PSGL-1(null) T cells were less efficient at entering lymph nodes, they also remained in lymph nodes longer than PSGL-1(+/+) T cells, suggesting that PSGL-1 supports T cell egress. In addition, PSGL-1(null) CD8(+) T cell proliferation was observed under steady-state conditions and PSGL-1(null) CD8(+) T cells were found to be hyperresponsive to homeostatic cytokines IL-2, IL-4, and IL-15. Despite these disturbances in T cell homeostasis, PSGL-1(null) mice exhibited a normal acute response (day 8) to lymphocytic choriomeningitis virus infection but generated an increased frequency of memory T cells (day 40). Our observations demonstrate a novel pleiotropic influence of PSGL-1 deficiency on several aspects of T cell homeostasis that would not have been anticipated based on the mild phenotype of PSGL-1(null) mice. These potentially offsetting effects presumably account for the near-normal cellularity seen in lymph nodes of PSGL-1(null) mice.

  14. Period 2 regulates neural stem/progenitor cell proliferation in the adult hippocampus

    OpenAIRE

    Albrecht Urs; Maquet Pierre; Moonen Gustave; Nguyen Laurent; Vandenbosch Renaud; Beukelaers Pierre; Borgs Laurence; Belachew Shibeshih; Malgrange Brigitte

    2009-01-01

    Abstract Background Newborn granule neurons are generated from proliferating neural stem/progenitor cells and integrated into mature synaptic networks in the adult dentate gyrus of the hippocampus. Since light/dark variations of the mitotic index and DNA synthesis occur in many tissues, we wanted to unravel the role of the clock-controlled Period2 gene (mPer2) in timing cell cycle kinetics and neurogenesis in the adult DG. Results In contrast to the suprachiasmatic nucleus, we observed a non-...

  15. Prohibitin 2 regulates the proliferation and lineage-specific differentiation of mouse embryonic stem cells in mitochondria.

    Directory of Open Access Journals (Sweden)

    Megumi Kowno

    Full Text Available BACKGROUND: The pluripotent state of embryonic stem (ES cells is controlled by a network of specific transcription factors. Recent studies also suggested the significant contribution of mitochondria on the regulation of pluripotent stem cells. However, the molecules involved in these regulations are still unknown. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we found that prohibitin 2 (PHB2, a pleiotrophic factor mainly localized in mitochondria, is a crucial regulatory factor for the homeostasis and differentiation of ES cells. PHB2 was highly expressed in undifferentiated mouse ES cells, and the expression was decreased during the differentiation of ES cells. Knockdown of PHB2 induced significant apoptosis in pluripotent ES cells, whereas enhanced expression of PHB2 contributed to the proliferation of ES cells. However, enhanced expression of PHB2 strongly inhibited ES cell differentiation into neuronal and endodermal cells. Interestingly, only PHB2 with intact mitochondrial targeting signal showed these specific effects on ES cells. Moreover, overexpression of PHB2 enhanced the processing of a dynamin-like GTPase (OPA1 that regulates mitochondrial fusion and cristae remodeling, which could induce partial dysfunction of mitochondria. CONCLUSIONS/SIGNIFICANCE: Our results suggest that PHB2 is a crucial mitochondrial regulator for homeostasis and lineage-specific differentiation of ES cells.

  16. HCV core protein-induced down-regulation of microRNA-152 promoted aberrant proliferation by regulating Wnt1 in HepG2 cells.

    Directory of Open Access Journals (Sweden)

    Shifeng Huang

    Full Text Available BACKGROUND: Hepatitis C virus (HCV has been reported to regulate cellular microRNAs (miRNAs. The HCV core protein is considered to be a potential oncoprotein in HCV-related hepatocellular carcinoma (HCV-HCC, but HCV core-regulated miRNAs are largely unknown. Our preliminary experiments revealed significant down-regulation of microRNA-152 (miR-152 by HCV core protein in HepG2 cells. Through target gene prediction softwares, Wnt1 was predicted to be a potential target of miR-152. The present study was initiated to investigate whether miR-152 is aberrantly regulated by the HCV core protein, and involved in the regulation of the aberrant proliferation of HCV-HCC cells. METHODS: MiR-152 levels were examined by stem-loop real-time RT-PCR (SLqRT-PCR. Cell proliferation was analyzed by MTT and colony formation assay. Cell cycle analysis was performed by flow cytometry. Luciferase reporter assay was conducted to confirm miRNA-target association. Wnt1 expression was determined by real-time qPCR and Western blotting. RESULTS: HCV core protein significantly suppressed miR-152 expression, and led to significant Wnt1 up-regulation with a concomitant aberrantly promoted proliferation. Moreover, we validated that miR-152 inhibition promoted, while miR-152 mimics inhibited cell proliferation. Using, qRT-PCR and western blot, Wnt1 was demonstrated to be regulated by miR-152. Luciferase activity assay showed that while miR-152 mimics significantly reduced the luciferase activity by 83.76% (P<0.0001, miR-152 inhibitor showed no effect on luciferase reporter. Most notably, salvage expression of miR-152 after Ad-HCV core infection for 24 h almost totally reversed the proliferation-promoting effect of the HCV core protein, and meanwhile, reduced the expression of both Wnt1 mRNA and protein to basal levels. CONCLUSION: These findings provide important evidence that the reduced miR-152 expression by HCV core protein can indirectly lose an inhibitory effect on Wnt1

  17. Regulation of proximal tubular cell differentiation and proliferation in primary culture by matrix stiffness and ECM components.

    Science.gov (United States)

    Chen, Wan-Chun; Lin, Hsi-Hui; Tang, Ming-Jer

    2014-09-15

    To explore whether matrix stiffness affects cell differentiation, proliferation, and transforming growth factor (TGF)-β1-induced epithelial-mesenchymal transition (EMT) in primary cultures of mouse proximal tubular epithelial cells (mPTECs), we used a soft matrix made from monomeric collagen type I-coated polyacrylamide gel or matrigel (MG). Both kinds of soft matrix benefited primary mPTECs to retain tubular-like morphology with differentiation and growth arrest and to evade TGF-β1-induced EMT. However, the potent effect of MG on mPTEC differentiation was suppressed by glutaraldehyde-induced cross-linking and subsequently stiffening MG or by an increasing ratio of collagen in the soft mixed gel. Culture media supplemented with MG also helped mPTECs to retain tubular-like morphology and a differentiated phenotype on stiff culture dishes as soft MG did. We further found that the protein level and activity of ERK were scaled with the matrix stiffness. U-0126, a MEK inhibitor, abolished the stiff matrix-induced dedifferentiation and proliferation. These data suggest that the ERK signaling pathway plays a vital role in matrix stiffness-regulated cell growth and differentiation. Taken together, both compliant property and specific MG signals from the matrix are required for the regulation of epithelial differentiation and proliferation. This study provides a basic understanding of how physical and chemical cues derived from the extracellular matrix regulate the physiological function of proximal tubules and the pathological development of renal fibrosis.

  18. TRPM7 channel regulates PDGF-BB-induced proliferation of hepatic stellate cells via PI3K and ERK pathways

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Ling, E-mail: fangling_1984@126.com; Zhan, Shuxiang; Huang, Cheng; Cheng, Xi; Lv, Xiongwen; Si, Hongfang; Li, Jun, E-mail: lj@ahmu.edu.cn

    2013-11-01

    TRPM7, a non-selective cation channel of the TRP channel superfamily, is implicated in diverse physiological and pathological processes including cell proliferation. Recently, TRPM7 has been reported in hepatic stellate cells (HSCs). Here, we investigated the contribution role of TRPM7 in activated HSC-T6 cell (a rat hepatic stellate cell line) proliferation. TRPM7 mRNA and protein were measured by RT-PCR and Western blot in rat model of liver fibrosis in vivo and PDGF-BB-activated HSC-T6 cells in vitro. Both mRNA and protein of TRPM7 were dramatically increased in CCl{sub 4}-treated rat livers. Stimulation of HSC-T6 cells with PDGF-BB resulted in a time-dependent increase of TRPM7 mRNA and protein. However, PDGF-BB-induced HSC-T6 cell proliferation was inhibited by non-specific TRPM7 blocker 2-aminoethoxydiphenyl borate (2-APB) or synthetic siRNA targeting TRPM7, and this was accompanied by downregulation of cell cycle proteins, cyclin D1, PCNA and CDK4. Blockade of TRPM7 channels also attenuated PDGF-BB induced expression of myofibroblast markers as measured by the induction of α-SMA and Col1α1. Furthermore, the phosphorylation of ERK and AKT, associated with cell proliferation, decreased in TRPM7 deficient HSC-T6 cells. These observations suggested that TRPM7 channels contribute to perpetuated fibroblast activation and proliferation of PDGF-BB induced HSC-T6 cells via the activation of ERK and PI3K pathways. Therefore, TRPM7 may constitute a useful target for the treatment of liver fibrosis. - Highlights: • Upregulation of TRPM7 mRNA and protein in the fibrotic livers from CCl{sub 4}-treated rats. • Increasing expression of TRPM7 mRNA and protein during HSC activation. • Blockade of TRPM7 inhibited the PDGF-BB induced proliferation of HSC-T6 cells. • Blockade of TRPM7 decreased α-SMA and Col1α1 expressions in activated HSC-T6 cells. • TRPM7 up-regulation contributes to the activation of ERK and AKT pathways.

  19. Regulation of Neuronal Stem Cell Proliferation in the Hippocampus by Endothelial Ceramide

    Directory of Open Access Journals (Sweden)

    Anne Gulbins

    2016-08-01

    Full Text Available Background/Aims: Major depressive disorder is one of the most common diseases in western countries. The disease is mainly defined by its psychiatric symptoms. However, the disease has also many symptoms outside the central nervous system, in particular cardiovascular symptoms. Recent studies demonstrated that the acid sphingomyelinase/ceramide system plays an important role in the development of major depressive disorder and functions as a target of antidepressants. Methods: Here, we investigated (i whether ceramide accumulates in endothelial cells in the neurogenetic zone of the hippocampus after glucocorticosterone-mediated stress, (ii whether ceramide is released into the extracellular space of the hippocampus and (iii whether extracellular ceramide inhibits neuronal proliferation. Ceramide was determined in endothelial cell culture supernatants or extracellular hippocampus extracts by a kinase assay. Endothelial ceramide in the hippocampus was analyzed by confocal microscopy of brain sections stained with Cy3-labelled anti-ceramide antibodies and FITC-Isolectin B4. Neuronal proliferation was measured by incubation of pheochromocytoma neuronal cells with culture supernatants and extracellular hippocampus extracts. Results: Treatment of cultured endothelial cells with glucocorticosterone induces a release of ceramide into the supernatant. Likewise, treatment of mice with glucocorticosterone triggers a release of ceramide into the extracellular space of the hippocampus. The release of ceramide is inhibited by concomitant treatment with the antidepressant amitriptyline, which also inhibits the activity of the acid sphingomyelinase. Studies employing confocal microscopy revealed that ceramide is formed and accumulates exclusively in endothelial cells in the hippocampus of stressed mice, a process that was again prevented by co-application of amitriptyline. Ceramide released in the culture supernatant or into the extracellular space of the

  20. BRAF activated non-coding RNA (BANCR) promoting gastric cancer cells proliferation via regulation of NF-κB1

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhi-Xin; Liu, Zhi-Qiang; Jiang, Biao; Lu, Xin-Yang; Ning, Xiao-Fei [Department of Gastrointestinal Surgery, Affiliated Hospital of Jining Medical University, Jining 272029 (China); Yuan, Chuan-Tao [Department of Pathology, Affiliated Hospital of Jining Medical University, Jining 272029 (China); Wang, Ai-Liang, E-mail: wang_ailiang@126.com [Department of Gastrointestinal Surgery, Affiliated Hospital of Jining Medical University, Jining 272029 (China)

    2015-09-18

    Background and objective: Long non-coding RNA, BANCR, has been demonstrated to contribute to the proliferation and migration of tumors. However, its molecular mechanism underlying gastric cancer is still unknown. In present study, we investigated whether BANCR was involved in the development of gastric cancer cells via regulation of NF-κB1. Methods: Human gastric cancer tissues were isolated as well as human gastric cell lines MGC803 and BGC823 were cultured to investigate the role of BANCR in gastric cancer. Results: BANCR expression was significantly up-regulated in gastric tumor tissues and gastric cell lines. Down-regulation of BANCR inhibited gastric cancer cell growth and promoted cell apoptosis, and it also contributed to a significant decrease of NF-κB1 (P50/105) expression and 3′UTR of NF-κB1 activity. Overexpression of NF-κB1 reversed the effect of BANCR on cancer cell growth and apoptosis. MiroRNA-9 (miR-9) targeted NF-κB1, and miR-9 inhibitor also reversed the effects of BANCR on gastric cancer cell growth and apoptosis. Conclusion: BANCR was highly expressed both in gastric tumor tissues and in cancer cells. NF-κB1 and miR-9 were involved in the role of BANCR in gastric cancer cell growth and apoptosis. - Highlights: • BANCR up-regulated in gastric cancer (GC) tissues and cell lines MGC803 and BGC823. • Down-regulation of BANCR inhibited GC cell growth and promoted cell apoptosis. • Down-regulation of BANCR contributed to decreased 3′UTR of NF-κB1 and its expression. • Overexpressed NF-κB1 reversed the effect of BANCR on GC cell growth. • miR-9 inhibitor reversed the effect of BANCR on cancer GC cell growth.

  1. DEC2 is a negative regulator for the proliferation and differentiation of chondrocyte lineage-committed mesenchymal stem cells.

    Science.gov (United States)

    Sasamoto, Tomoko; Fujimoto, Katsumi; Kanawa, Masami; Kimura, Junko; Takeuchi, Junpei; Harada, Naoko; Goto, Noriko; Kawamoto, Takeshi; Noshiro, Mitsuhide; Suardita, Ketut; Tanne, Kazuo; Kato, Yukio

    2016-09-01

    Differentiated embryo chondrocyte 2 (DEC2) is a basic helix-loop-helix-Orange transcription factor that regulates cell differentiation in various mammalian tissues. DEC2 has been shown to suppress the differentiation of mesenchymal stem cells (MSCs) into myocytes and adipocytes. In the present study, we examined the role of DEC2 in the chondrogenic differentiation of human MSCs. The overexpression of DEC2 exerted minimal effects on the proliferation of MSCs in monolayer cultures with the growth medium under undifferentiating conditions, whereas it suppressed increases in DNA content, glycosaminoglycan content, and the expression of several chondrocyte-related genes, including aggrecan and type X collagen alpha 1, in MSC pellets in centrifuge tubes under chondrogenic conditions. In the pellets exposed to chondrogenesis induction medium, DEC2 overexpression downregulated the mRNA expression of fibroblast growth factor 18, which is involved in the proliferation and differentiation of chondrocytes, and upregulated the expression of p16INK4, which is a cell cycle inhibitor. These findings suggest that DEC2 is a negative regulator of the proliferation and differentiation of chondrocyte lineage-committed mesenchymal cells. PMID:27430159

  2. MARCKS Signaling Differentially Regulates Vascular Smooth Muscle and Endothelial Cell Proliferation through a KIS-, p27kip1- Dependent Mechanism.

    Directory of Open Access Journals (Sweden)

    Dan Yu

    Full Text Available Overexpression of the myristolated alanine-rich C kinase substrate (MARCKS occurs in vascular proliferative diseases such as restenosis after bypass surgery. MARCKS knockdown results in arrest of vascular smooth muscle cell (VSMC proliferation with little effect on endothelial cell (EC proliferation. We sought to identify the mechanism of differential regulation by MARCKS of VSMC and EC proliferation in vitro and in vivo.siRNA-mediated MARCKS knockdown in VSMCs inhibited proliferation and prevented progression from phase G0/G1 to S. Protein expression of the cyclin-dependent kinase inhibitor p27kip1, but not p21cip1 was increased by MARCKS knockdown. MARCKS knockdown did not affect proliferation in VSMCs derived from p27kip1-/- mice indicating that the effect of MARCKS is p27kip1-dependent. MARCKS knockdown resulted in decreased phosphorylation of p27kip1 at threonine 187 and serine 10 as well as, kinase interacting with stathmin (KIS, cyclin D1, and Skp2 expression. Phosphorylation of p27kip1 at serine 10 by KIS is required for nuclear export and degradation of p27kip1. MARCKS knockdown caused nuclear trapping of p27kip1. Both p27kip1 nuclear trapping and cell cycle arrest were released by overexpression of KIS, but not catalytically inactive KIS. In ECs, MARCKS knockdown paradoxically increased KIS expression and cell proliferation. MARCKS knockdown in a murine aortic injury model resulted in decreased VSMC proliferation determined by bromodeoxyuridine (BrdU integration assay, and inhibition of vascular wall thickening. MARCKS knockdown increased the rate of re-endothelialization.MARCKS knockdown arrested VSMC cell cycle by decreasing KIS expression. Decreased KIS expression resulted in nuclear trapping of p27kip1 in VSMCs. MARCKS knockdown paradoxically increased KIS expression in ECs resulting in increased EC proliferation. MARCKS knockdown significantly attenuated the VSMC proliferative response to vascular injury, but accelerated

  3. Overexpressed ubiquitin ligase Cullin7 in breast cancer promotes cell proliferation and invasion via down-regulating p53

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hongsheng [Department of Histology and Embryology, Guangdong Medical College, Dongguan 523808, Guangdong (China); Wu, Fenping [The 7th People’s Hospital of Chengdu, Chengdu 610041, Sichuan (China); Wang, Yan [The Second School of Clinical Medicine, Guangdong Medical College, Dongguan 523808, Guangdong (China); Yan, Chong [School of Pharmacy, Guangdong Medical College, Dongguan 523808, Guangdong (China); Su, Wenmei, E-mail: wenmeisutg@126.com [Oncology of Affiliated Hospital Guangdong Medical College, Zhanjiang 524000, Guangdong (China)

    2014-08-08

    Highlights: • Cullin7 is overexpressed in human breast cancer samples. • Cullin7 stimulated proliferation and invasion of breast cancer cells. • Inhibition of p53 contributes to Cullin7-induced proliferation and invasion. - Abstract: Ubiquitin ligase Cullin7 has been identified as an oncogene in some malignant diseases such as choriocarcinoma and neuroblastoma. However, the role of Cullin7 in breast cancer carcinogenesis remains unclear. In this study, we compared Cullin7 protein levels in breast cancer tissues with normal breast tissues and identified significantly higher expression of Cullin7 protein in breast cancer specimens. By overexpressing Cullin7 in breast cancer cells HCC1937, we found that Cullin7 could promote cell growth and invasion in vitro. In contrast, the cell growth and invasion was inhibited by silencing Cullin7 in breast cancer cell BT474. Moreover, we demonstrated that Cullin7 promoted breast cancer cell proliferation and invasion via down-regulating p53 expression. Thus, our study provided evidence that Cullin7 functions as a novel oncogene in breast cancer and may be a potential therapeutic target for breast cancer management.

  4. Nucleosome Assembly Protein 1-Like 1 (Nap1l1 Regulates the Proliferation of Murine Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Yuan Yan

    2016-01-01

    Full Text Available Background/Aims: To investigate whether nucleosome assembly protein 1-like 1 (Nap1l1 regulates the proliferation of induced pluripotent stem cells (iPSC and the potential mechanisms. Methods: Nap1l1-knockdown-iPSC and Nap1l1-overexpression-iPSC were constructed by transfection of lentiviral particles. The proliferation of iPSC was detected by MTT analysis, and cell cycle was analyzed by flow cytometry. Results: Nap1l1 overexpression promoted iPSC proliferation and induced G2/M transition compared to their control iPSC while Nap1l1-knockdown-iPSC dramatically displayed the reduced proliferation and accumulated G2/M phase cells. Further analysis showed that Nap1l1 overexpression in iPSC increased the expression of cyclin B1, downregulated the expression of p21 and p27, while knockdown of Nap1l1 showed the opposite effects. In addition, overexpression of Nap1l1 promoted the phosphorylation of AKT and ERK in iPSC, while knockdown of Nap1l1 inhibited the effects. However, these effects displayed in Nap1l1-overexpression-iPSC were greatly suppressed by the inhibition of AKT or ERK signaling. Conclusions: The results indicate that Nap1l1 promotes the proliferation of iPSC attributable to G2/M transition caused by downregulation of p27 and p21, and upregulation of cyclin B1, the activation of AKT or ERK is involved in the process. The present study has revealed a novel molecular mechanism involved in the proliferation of iPSC.

  5. The TLX-miR-219 cascade regulates neural stem cell proliferation in neurodevelopment and schizophrenia iPSC model.

    Science.gov (United States)

    Murai, Kiyohito; Sun, Guoqiang; Ye, Peng; Tian, E; Yang, Su; Cui, Qi; Sun, Guihua; Trinh, Daniel; Sun, Olivia; Hong, Teresa; Wen, Zhexing; Kalkum, Markus; Riggs, Arthur D; Song, Hongjun; Ming, Guo-li; Shi, Yanhong

    2016-03-11

    Dysregulated expression of miR-219, a brain-specific microRNA, has been observed in neurodevelopmental disorders, such as schizophrenia (SCZ). However, its role in normal mammalian neural stem cells (NSCs) and in SCZ pathogenesis remains unknown. We show here that the nuclear receptor TLX, an essential regulator of NSC proliferation and self-renewal, inhibits miR-219 processing. miR-219 suppresses mouse NSC proliferation downstream of TLX. Moreover, we demonstrate upregulation of miR-219 and downregulation of TLX expression in NSCs derived from SCZ patient iPSCs and DISC1-mutant isogenic iPSCs. SCZ NSCs exhibit reduced cell proliferation. Overexpression of TLX or inhibition of miR-219 action rescues the proliferative defect in SCZ NSCs. Therefore, this study uncovers an important role for TLX and miR-219 in both normal neurodevelopment and in SCZ patient iPSC-derived NSCs. Moreover, this study reveals an unexpected role for TLX in regulating microRNA processing, independent of its well-characterized role in transcriptional regulation.

  6. SLy1 regulates T-cell proliferation during Listeria monocytogenes infection in a Foxo1-dependent manner.

    Science.gov (United States)

    Schäll, Daniel; Schmitt, Fee; Reis, Bernhard; Brandt, Simone; Beer-Hammer, Sandra

    2015-11-01

    Infection of mice with Listeria monocytogenes results in a strong T-cell response that is critical for an efficient defense. Here, we demonstrate that the adapter protein SLy1 (SH3-domain protein expressed in Lymphocytes 1) is essential for the generation of a fully functional T-cell response. The lack of SLy1 leads to reduced survival rates of infected mice. The increased susceptibility of SLy1 knock-out (KO) mice was caused by reduced proliferation of differentiated T cells. Ex vivo analyses of isolated SLy1 KO T cells displayed a dysregulation of Forkhead box protein O1 shuttling after TCR signaling, which resulted in an increased expression of cell cycle inhibiting genes, and therefore, reduced expansion of the T-cell population. Forkhead box protein O1 shuttles to the cytoplasm after phosphorylation in a protein complex including 14-3-3 proteins. Interestingly, we observed a similar regulation for the adapter protein SLy1, where TCR stimulation results in SLy1 phosphorylation and SLy1 export to the cytoplasm. Moreover, immunoprecipitation analyses revealed a binding of SLy1 to 14-3-3 proteins. Altogether, this study describes SLy1 as an immunoregulatory protein, which is involved in the generation of adaptive immune responses during L. monocytogenes infection, and provides a model of how SLy1 regulates T-cell proliferation. PMID:26306874

  7. Comparative Phosphoproteomics Analysis of VEGF and Angiopoietin-1 Signaling Reveals ZO-1 as a Critical Regulator of Endothelial Cell Proliferation.

    Science.gov (United States)

    Chidiac, Rony; Zhang, Ying; Tessier, Sylvain; Faubert, Denis; Delisle, Chantal; Gratton, Jean-Philippe

    2016-05-01

    VEGF and angiopoietin-1 (Ang-1) are essential factors to promote angiogenesis through regulation of a plethora of signaling events in endothelial cells (ECs). Although pathways activated by VEGF and Ang-1 are being established, the unique signaling nodes conferring specific responses to each factor remain poorly defined. Thus, we conducted a large-scale comparative phosphoproteomic analysis of signaling pathways activated by VEGF and Ang-1 in ECs using mass spectrometry. Analysis of VEGF and Ang-1 networks of regulated phosphoproteins revealed that the junctional proteins ZO-1, ZO-2, JUP and p120-catenin are part of a cluster of proteins phosphorylated following VEGF stimulation that are linked to MAPK1 activation. Down-regulation of these junctional proteins led to MAPK1 activation and accordingly, increased proliferation of ECs stimulated specifically by VEGF, but not by Ang-1. We identified ZO-1 as the central regulator of this effect and showed that modulation of cellular ZO-1 levels is necessary for EC proliferation during vascular development of the mouse postnatal retina. In conclusion, we uncovered ZO-1 as part of a signaling node activated by VEGF, but not Ang-1, that specifically modulates EC proliferation during angiogenesis. PMID:26846344

  8. miR-208-3p promotes hepatocellular carcinoma cell proliferation and invasion through regulating ARID2 expression

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Peng; Wu, Dingguo; You, Yu; Sun, Jing; Lu, Lele; Tan, Jiaxing; Bie, Ping, E-mail: bieping2010@163.com

    2015-08-15

    MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression at post-transcriptional level. miRNA dysregulation plays a causal role in cancer progression. In this study, miR-208-3p was highly expressed and directly repressed ARID2 expression. As a result, ARID2 expression in hepatocellular carcinoma (HCC) was decreased. In vitro, miR-208-3p down-regulation and ARID2 over-expression elicited similar inhibitory effects on HCC cell proliferation and invasion. In vivo test results revealed that miR-208-3p down-regulation inhibited HCC tumorigenesis in Hep3B cells. Moreover, ARID2 was possibly a downstream element of transforming growth factor beta1 (TGFβ1)/miR-208-3p/ARID2 regulatory pathway. These findings suggested that miR-208-3p up-regulation is associated with HCC cell progression and may provide a new target for liver cancer treatment. - Highlights: • miR-208-3p was highly expressed and directly repressed the expression of ARID2 in HCC. • miR-208-3p contributed to HCC cell progression both in vitro and in vivo. • Over-expression of ARID2 inhibited the HCC cell proliferation and invasion. • Restoration of ARID2 partly reversed the the effect of miR-208-3p down-regulation on HCC cells. • Newly regulatory pathway: miR-208-3p mediated the repression of ARID2 by TGFβ1 in HCC cells.

  9. The splicing activator DAZAP1 integrates splicing control into MEK/Erk-regulated cell proliferation and migration

    Science.gov (United States)

    Choudhury, Rajarshi; Roy, Sreerupa Ghose; Tsai, Yihsuan S.; Tripathy, Ashutosh; Graves, Lee M.; Wang, Zefeng

    2014-01-01

    Alternative splicing of pre-messenger RNA (mRNA) is a critical stage of gene regulation in response to environmental stimuli. Here we show that DAZAP1, an RNA-binding protein involved in mammalian development and spermatogenesis, promotes inclusion of weak exons through specific recognition of diverse cis-elements. The carboxy-terminal proline-rich domain of DAZAP1 interacts with and neutralizes general splicing inhibitors, and is sufficient to activate splicing when recruited to pre-mRNA. This domain is phosphorylated by the MEK/Erk (extracellular signal-regulated protein kinase) pathway and this modification is essential for the splicing regulatory activity and the nuclear/cytoplasmic translocation of DAZAP1. Using mRNA-seq, we identify endogenous splicing events regulated by DAZAP1, many of which are involved in maintaining cell growth. Knockdown or over-expression of DAZAP1 causes a cell proliferation defect. Taken together, these studies reveal a molecular mechanism that integrates splicing control into MEK/Erk-regulated cell proliferation.

  10. Regulation of Axolotl (Ambystoma mexicanum) Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Science.gov (United States)

    Lehrberg, Jeffrey; Gardiner, David M

    2015-01-01

    We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response. PMID:25923915

  11. Regulation of Axolotl (Ambystoma mexicanum) Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Science.gov (United States)

    Lehrberg, Jeffrey; Gardiner, David M

    2015-01-01

    We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

  12. Regulation of Axolotl (Ambystoma mexicanum Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Directory of Open Access Journals (Sweden)

    Jeffrey Lehrberg

    Full Text Available We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

  13. Down regulation of pRb in cultures of avian neuroretina cells promotes proliferation of reactive Müller-like cells and emergence of retinal stem/progenitors.

    Science.gov (United States)

    Marx, Maria; Lebuhotel, Céline; Laugier, Danielle; Chapelle, Audrey; Calothy, Georges; Saule, Simon

    2010-06-01

    The aim of this work was to define the role of pRb depletion in the proliferation and differentiation of avian retinoblasts in vitro. For this purpose vectors expressing pRb short hairpin RNA were used to deplete pRb in cultures of avian neuroretinal cells. Down regulation of pRb was observed by Western blot and quantification of nuclear pRb. Cell proliferation and differentiation were studied following BrdU labeling and immunostaining. Transfection significantly down-regulated pRb in neuroretinal cells. Long-term effect of pRb depletion mainly induced proliferation of epithelial-like cells that expressed markers of reactive Müller glial cells. A minority of these cells that survived passaging could be maintained as neurosphere-like aggregates with low pRb, not observed in control cultures. BrdU labeling followed by a two week chase showed the presence of cells still remained labelled, indicating low cell cycling. Under appropriate conditions, these aggregates differentiate in precursors of amacrine interneurons shown by the expression of AP2, in absence of the photoreceptors marker visinin and the late neuronal marker MAP2. Taken together these data show that decrease pRb level in cultures of avian neuroretinal cells promotes the emergence and proliferation of stem cell/progenitors from reactive-like Muller cells.

  14. PAX5 promotes pre-B cell proliferation by regulating the expression of pre-B cell receptor and its downstream signaling.

    Science.gov (United States)

    Xue, Kai; Song, Jiazhe; Yang, Yan; Li, Zhi; Wu, Chunhua; Jin, Jinhua; Li, Wenzhe

    2016-05-01

    PAX5 is indispensable for the commitment of early lymphoid progenitors to the B cell lineage as well as for the development of B cells. Although previous studies have indicated that the Pax5-conditional-knockout mouse exhibited dedifferentiation of mature B cell and the development of aggressive lymphomas, the changes of Pax5 gene expressions in pre-B cells have not been analyzed. To understand the functional importance of Pax5 gene in the proliferation and survival of pre-B cells, we established a Pax5-knockdown model using 70Z/3 pre-B cell line. Pax5 knockdown 70Z/3 cells (70Z/3-KD cells) showed down-regulations of pre-BCR compounds such as CD19, BLNK, Id2 and λ5. The signaling via pre-BCRs was significantly diminished in the 70Z/3-KD cells, and this alteration was normalized by restored Pax5 gene expression. Loss of PAX5 reduced the growth rates in the 70Z/3-KD cells, compared to the mock cells. Meanwhile, the proliferation of pre-B cells was reduced by the knockdown of Pax5 gene. Moreover, further examinations showed that PAX5 was also activated in B cell acute lymphoblastic leukemia (B-ALL) as a cell proliferation enhancer. These findings suggested that pax5 is critically important for the proliferation and survival of pre-B cells. PMID:27016671

  15. miR-664 negatively regulates PLP2 and promotes cell proliferation and invasion in T-cell acute lymphoblastic leukaemia

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    Zhu, Hong; Miao, Mei-hua; Ji, Xue-qiang; Xue, Jun; Shao, Xue-jun, E-mail: xuejunshao@hotmail.com

    2015-04-03

    MicroRNAs (miRNAs) play important roles in the pathogenesis of many types of cancers by negatively regulating gene expression at posttranscriptional level. However, the role of microRNAs in leukaemia, particularly T-cell acute lymphoblastic leukaemia (T-ALL), has remained elusive. Here, we identified miR-664 and its predicted target gene PLP2 were differentially expressed in T-ALL using bioinformatics methods. In T-ALL cell lines, CCK-8 proliferation assay indicated that the cell proliferation was promoted by miR-664, while miR-664 inhibitor could significantly inhibited the proliferation. Moreover, migration and invasion assay showed that overexpression of miR-664 could significantly promoted the migration and invasion of T-ALL cells, whereas miR-664 inhibitor could reduce cell migration and invasion. luciferase assays confirmed that miR-664 directly bound to the 3'untranslated region of PLP2, and western blotting showed that miR-664 suppressed the expression of PLP2 at the protein levels. This study indicated that miR-664 negatively regulates PLP2 and promotes proliferation and invasion of T-ALL cell lines. Thus, miR-664 may represent a potential therapeutic target for T-ALL intervention. - Highlights: • miR-664 mimics promote the proliferation and invasion of T-ALL cells. • miR-664 inhibitors inhibit the proliferation and invasion of T-ALL cells. • miR-664 targets 3′ UTR of PLP2 in T-ALL cells. • miR-664 negatively regulates PLP2 in T-ALL cells.

  16. A multi-resource data integration approach: Identification of candidate genes regulating cell proliferation during neocortical development

    Directory of Open Access Journals (Sweden)

    Cynthia M Vied

    2014-08-01

    Full Text Available Neurons of the mammalian neocortex are produced by proliferating cells located in the ventricular zone (VZ lining the lateral ventricles. This is a complex and sequential process, requiring precise control of cell cycle progression, fate commitment and differentiation. We have analyzed publicly available databases from mouse and human to identify candidate genes that are potentially involved in regulating early neocortical development and neurogenesis. We used a mouse in situ hybridization dataset (The Allen Institute for Brain Science to identify 13 genes (Cdon, Celsr1, Dbi, E2f5, Eomes, Hmgn2, Neurog2, Notch1, Pcnt, Sox3, Ssrp1, Tead2, Tgif2 with high correlation of expression in the proliferating cells of the VZ of the neocortex at early stages of development (E15.5. We generated a similar human brain network using microarray and RNA-seq data (BrainSpan Atlas and identified 407 genes with high expression in the developing human VZ and subventricular zone (SVZ at 8-9 post-conception weeks. Seven of the human genes were also present in the mouse VZ network. The human and mouse networks were extended using available genetic and proteomic datasets through GeneMANIA. A gene ontology search of the mouse and human networks indicated that many of the genes are involved in the cell cycle, DNA replication, mitosis and transcriptional regulation. The reported involvement of Cdon, Celsr1, Dbi, Eomes, Neurog2, Notch1, Pcnt, Sox3, Tead2 and Tgif2 in neural development or diseases resulting from the disruption of neurogenesis validates these candidate genes. Taken together, our knowledge-based discovery method has validated the involvement of many genes already known to be involved in neocortical development and extended the potential number of genes by 100's, many of which are involved in functions related to cell proliferation but others of which are potential candidates for involvement in the regulation of neocortical development.

  17. Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase pathway

    International Nuclear Information System (INIS)

    Highlights: ► The expression levels of Bex2 markedly increased in glioma tissues. ► Bex2 over-expression promoted cell proliferation, while its down-regulation inhibited cell growth. ► Bex2 down-regulation promoted cell apoptosis via JNK/c-Jun signaling pathway. -- Abstract: The function of Bex2, a member of the Brain Expressed X-linked gene family, in glioma is controversial and its mechanism is largely unknown. We report here that Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase (JNK) pathway. The expression level of Bex2 is markedly increased in glioma tissues. We observed that Bex2 over-expression promotes cell proliferation, while down-regulation of Bex2 inhibits cell growth. Furthermore, Bex2 down-regulation promotes cell apoptosis and activates the JNK pathway; these effects were abolished by administration of the JNK specific inhibitor, (SP600125). Thus, Bex2 may be an important player during the development of glioma.

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Liang; Zhang, Yubao, E-mail: zhyb880077@sina.com

    2015-02-13

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

  19. pRb phosphorylation regulates the proliferation of supporting cells in gentamicin-damaged neonatal avian utricle.

    Science.gov (United States)

    Wu, Jingfang; Sun, Shan; Li, Wenyan; Chen, Yan; Li, Huawei

    2014-10-01

    The ability of nonmammalian vertebrates to regenerate hair cells (HCs) after damage-induced HC loss has stimulated and inspired research in the field of HC regeneration. The protein pRb encoded by retinoblastoma gene Rb1 forces sensory progenitor cells to exit cell cycle and maintain differentiated HCs and supporting cells (SCs) in a quiescent state. pRb function is regulated by phosphorylation through the MEK/ERK or the pRb/Raf-1 signaling pathway. In our previous study, we have shown that pRb phosphorylation is crucial for progenitor cell proliferation and survival during the early embryonic stage of avian otocyst sensory epithelium development. However, in damaged avian utricle, the role of pRb in regulating the cell cycling of SCs or HCs regeneration still remains unclear. To further elucidate the function of pRb phosphorylation on SCs re-entering the cell cycle triggered by gentamycin-induced HCs damage, we isolated neonatal chicken utricles and treated them with the MEK inhibitor U0126 or the pRb/Raf-1 inhibitor RRD-251, respectively in vitro. We found that after gentamycin-induced HCs damage, pRb phosphorylation is important for the quiescent SCs re-entering the cell cycle in the neonatal chicken utricle. In addition, the proliferation of SCs decreased in a dose-dependent manner in response to both U0126 and RRD-251, which indicates that both the MEK/ERK and the pRb/Raf-1 signaling pathway play important roles in pRb phosphorylation in damaged neonatal chicken utricle. Together, these findings on the function of pRb in damaged neonatal chicken utricle improve our understanding of the regulation of the cell cycle of SCs after HCs loss and may shed light on the mammalian HC regeneration from SCs in damaged organs.

  20. The G1/S Specific Cyclin D2 Is a Regulator of HIV-1 Restriction in Non-proliferating Cells.

    Science.gov (United States)

    Badia, Roger; Pujantell, Maria; Riveira-Muñoz, Eva; Puig, Teresa; Torres-Torronteras, Javier; Martí, Ramón; Clotet, Bonaventura; Ampudia, Rosa M; Vives-Pi, Marta; Esté, José A; Ballana, Ester

    2016-08-01

    Macrophages are a heterogeneous cell population strongly influenced by differentiation stimuli that become susceptible to HIV-1 infection after inactivation of the restriction factor SAMHD1 by cyclin-dependent kinases (CDK). Here, we have used primary human monocyte-derived macrophages differentiated through different stimuli to evaluate macrophage heterogeneity on cell activation and proliferation and susceptibility to HIV-1 infection. Stimulation of monocytes with GM-CSF induces a non-proliferating macrophage population highly restrictive to HIV-1 infection, characterized by the upregulation of the G1/S-specific cyclin D2, known to control early steps of cell cycle progression. Knockdown of cyclin D2, enhances HIV-1 replication in GM-CSF macrophages through inactivation of SAMHD1 restriction factor by phosphorylation. Co-immunoprecipitation experiments show that cyclin D2 forms a complex with CDK4 and p21, a factor known to restrict HIV-1 replication by affecting the function of the downstream cascade that leads to SAMHD1 deactivation. Thus, we demonstrate that cyclin D2 acts as regulator of cell cycle proteins affecting SAMHD1-mediated HIV-1 restriction in non-proliferating macrophages. PMID:27541004

  1. NF-YB Regulates Spermatogonial Stem Cell Self-Renewal and Proliferation in the Planarian Schmidtea mediterranea

    Science.gov (United States)

    Iyer, Harini; Collins, James J.; Newmark, Phillip A.

    2016-01-01

    Gametes are the source and carrier of genetic information, essential for the propagation of all sexually reproducing organisms. Male gametes are derived from a progenitor stem cell population called spermatogonial stem cells (SSCs). SSCs give rise to male gametes through the coordination of two essential processes: self-renewal to produce more SSCs, and differentiation to produce mature sperm. Disruption of this equilibrium can lead to excessive proliferation of SSCs, causing tumorigenesis, or can result in aberrant differentiation, leading to infertility. Little is known about how SSCs achieve the fine balance between self-renewal and differentiation, which is necessary for their remarkable output and developmental potential. To understand the mechanisms of SSC maintenance, we examine the planarian homolog of Nuclear Factor Y-B (NF-YB), which is required for the maintenance of early planarian male germ cells. Here, we demonstrate that NF-YB plays a role in the self-renewal and proliferation of planarian SSCs, but not in their specification or differentiation. Furthermore, we characterize members of the NF-Y complex in Schistosoma mansoni, a parasitic flatworm related to the free-living planarian. We find that the function of NF-YB in regulating male germ cell proliferation is conserved in schistosomes. This finding is especially significant because fecundity is the cause of pathogenesis of S. mansoni. Our findings can help elucidate the complex relationship between self-renewal and differentiation of SSCs, and may also have implications for understanding and controlling schistosomiasis. PMID:27304889

  2. Aryl hydrocarbon receptor nuclear translocator (ARNT) isoforms control lymphoid cancer cell proliferation through differentially regulating tumor suppressor p53 activity.

    Science.gov (United States)

    Gardella, Kacie A; Muro, Israel; Fang, Gloria; Sarkar, Krishnakali; Mendez, Omayra; Wright, Casey W

    2016-03-01

    The aryl hydrocarbon receptor nuclear translocator (ARNT) is involved in xenobiotic and hypoxic responses, and we previously showed that ARNT also regulates nuclear factor-κB (NF-κB) signaling by altering the DNA binding activity of the RelB subunit. However, our initial study of ARNT-mediated RelB modulation was based on simultaneous suppression of the two ARNT isoforms, isoform 1 and 3, and precluded the examination of their individual functions. We find here that while normal lymphocytes harbor equal levels of isoform 1 and 3, lymphoid malignancies exhibit a shift to higher levels of ARNT isoform 1. These elevated levels of ARNT isoform 1 are critical to the proliferation of these cancerous cells, as suppression of isoform 1 in a human multiple myeloma (MM) cell line, and an anaplastic large cell lymphoma (ALCL) cell line, triggered S-phase cell cycle arrest, spontaneous apoptosis, and sensitized cells to doxorubicin treatment. Furthermore, co-suppression of RelB or p53 with ARNT isoform 1 prevented cell cycle arrest and blocked doxorubicin induced apoptosis. Together our findings reveal that certain blood cancers rely on ARNT isoform 1 to potentiate proliferation by antagonizing RelB and p53-dependent cell cycle arrest and apoptosis. Significantly, our results identify ARNT isoform 1 as a potential target for anticancer therapies.

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

    Directory of Open Access Journals (Sweden)

    Valencia-Hernández Armando

    2011-05-01

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

  4. Functional dissection of HOXD cluster genes in regulation of neuroblastoma cell proliferation and differentiation.

    Directory of Open Access Journals (Sweden)

    Yunhong Zha

    Full Text Available Retinoic acid (RA can induce growth arrest and neuronal differentiation of neuroblastoma cells and has been used in clinic for treatment of neuroblastoma. It has been reported that RA induces the expression of several HOXD genes in human neuroblastoma cell lines, but their roles in RA action are largely unknown. The HOXD cluster contains nine genes (HOXD1, HOXD3, HOXD4, and HOXD8-13 that are positioned sequentially from 3' to 5', with HOXD1 at the 3' end and HOXD13 the 5' end. Here we show that all HOXD genes are induced by RA in the human neuroblastoma BE(2-C cells, with the genes located at the 3' end being activated generally earlier than those positioned more 5' within the cluster. Individual induction of HOXD8, HOXD9, HOXD10 or HOXD12 is sufficient to induce both growth arrest and neuronal differentiation, which is associated with downregulation of cell cycle-promoting genes and upregulation of neuronal differentiation genes. However, induction of other HOXD genes either has no effect (HOXD1 or has partial effects (HOXD3, HOXD4, HOXD11 and HOXD13 on BE(2-C cell proliferation or differentiation. We further show that knockdown of HOXD8 expression, but not that of HOXD9 expression, significantly inhibits the differentiation-inducing activity of RA. HOXD8 directly activates the transcription of HOXC9, a key effector of RA action in neuroblastoma cells. These findings highlight the distinct functions of HOXD genes in RA induction of neuroblastoma cell differentiation.

  5. MicroRNA-450a-3p represses cell proliferation and regulates embryo development by regulating Bub1 expression in mouse.

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    Min Luo

    Full Text Available Bub1 is a critical component of the spindle assembly checkpoint (SAC and closely linked to cell proliferation and differentiation. We previously found that spontaneous abortion embryos contained a low level of Bub1 protein but normal mRNA level, while the knockdown of Bub1 leads to abnormal numerical chromosomes in embryonic cells. Here, we investigated the mechanism through which governs the post-transcriptional regulation of Bub1 protein expression level. We first conducted bioinformatics analysis and identified eight putative miRNAs that may target Bub1. Luciferase reporter assay confirmed that miR-450a-3p can directly regulate Bub1 by binding to the 3'-untranslated region of Bub1 mRNA. We found that the overexpression of miR-450a-3p in mouse embryonic fibroblast (MEF cells down-regulated Bub1 protein level, repressed cell proliferation, increased apoptosis and restricted most cells in G1 phase of the cell cycle. Furthermore, when the fertilized eggs were microinjected with miR-450a-3p mimics, the cleavage of zygotes was effectively suppressed. Our results strongly suggest that an abnormally decreased Bub1 level regulated by miRNAs may be implicated in the pathogenesis of spontaneous miscarriage. Therefore, the blockade of miR-450a-3p may be explored as a novel therapeutic strategy for preventing spontaneous miscarriages.

  6. Electroacupuncture Regulates Apoptosis/Proliferation of Intramuscular Interstitial Cells of Cajal and Restores Colonic Motility in Diabetic Constipation Rats

    Directory of Open Access Journals (Sweden)

    Juanjuan Xu

    2013-01-01

    Full Text Available Injury of interstitial cells of Cajal (ICC is associated with gut dysmotility in diabetic rats. We have shown an acceleration of the colonic contractility by electroacupuncture stimulation (EAS. However, little is known about potential roles of EAS on colonic transit and ICC. In this study, we evaluate the effect of EAS on colonic transit and investigate whether apoptosis/proliferation of ICC was involved in regulative effect of EAS on colonic transit. Rats were randomly assigned to normal, diabetic, diabetic-plus-sham stimulation, diabetic-plus-low-frequency stimulation, and diabetic-plus-high-frequency stimulation groups. Bead expulsion test was used for measuring the distal colonic transit. The Kit (ICC marker was detected by western blot. Apoptotic ICC was detected by terminal dUTP nucleotide end labeling. Proliferating ICC was identified by Kit/Ki67 double immunofluorescent staining on whole mount preparations. Ultrastructure changes of ICC were studied using electron microscopy. Results showed that high-frequency stimulation significantly promoted colonic transit. Low- and high-frequency stimulation markedly rescued intramuscular ICC from apoptosis. Abundant proliferating intramuscular ICC was found in low- and high-frequency stimulation groups. Our results indicate that high-frequency EAS has stimulatory effect on the distal colonic transit, which may be mediated by downregulation of the apoptosis and upregulation of the proliferation of intramuscular ICC.

  7. Estrogen induced {beta}-1,4-galactosyltransferase 1 expression regulates proliferation of human breast cancer MCF-7 cells

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hee-Jung [Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan (Korea, Republic of); Division of Applied Medicine, School of Korean Medicine, Pusan National University, Yangsan-city, Gyeongsangnam-do (Korea, Republic of); Chung, Tae-Wook; Kim, Cheorl-Ho [Department of Molecular and Cellular Glycobiology, College of Natural Science, Sungkyunkwan University, Suwon, Kyungki-do (Korea, Republic of); Jeong, Han-Sol; Joo, Myungsoo [Division of Applied Medicine, School of Korean Medicine, Pusan National University, Yangsan-city, Gyeongsangnam-do (Korea, Republic of); Youn, BuHyun, E-mail: bhyoun72@pusan.ac.kr [Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan (Korea, Republic of); Ha, Ki-Tae, E-mail: hagis@pusan.ac.kr [Division of Applied Medicine, School of Korean Medicine, Pusan National University, Yangsan-city, Gyeongsangnam-do (Korea, Republic of)

    2012-10-05

    Highlights: Black-Right-Pointing-Pointer We examined the regulation and biological functions of B4GALT1 expression induced by estrogen. Black-Right-Pointing-Pointer Estrogen-induced B4GALT1 expression through the direct binding of ER-{alpha} to ERE in MCF-7 cells. Black-Right-Pointing-Pointer B4GALT1 expression activates the proliferation of MCF-7 cells via its receptor function. Black-Right-Pointing-Pointer Thus, we suggest B4GALT1 as a molecular target for inhibiting breast cancer proliferation. -- Abstract: Beta 1,4-galactosyltransferase 1 (B4GALT1) synthesizes galactose {beta}-1,4-N-acetylglucosamine (Gal{beta}1-4GlcNAc) groups on N-linked sugar chains of glycoproteins, which play important roles in many biological events, including the proliferation and migration of cancer cells. A previous microarray study reported that this gene is expressed by estrogen treatment in breast cancer. In this study, we examined the regulatory mechanisms and biological functions of estrogen-induced B4GALT1 expression. Our data showed that estrogen-induced expression of B4GALT1 is localized in intracellular compartments and in the plasma membrane. In addition, B4GALT1 has an enzyme activity involved in the production of the Gal{beta}1-4GlcNAc structure. The result from a promoter assay and chromatin immunoprecipitation revealed that 3 different estrogen response elements (EREs) in the B4GALT1 promoter are critical for responsiveness to estrogen. In addition, the estrogen antagonists ICI 182,780 and ER-{alpha}-ERE binding blocker TPBM inhibit the expression of estrogen-induced B4GALT1. However, the inhibition of signal molecules relating to the extra-nuclear pathway, including the G-protein coupled receptors, Ras, and mitogen-activated protein kinases, had no inhibitory effects on B4GALT1 expression. The knock-down of the B4GALT1 gene and the inhibition of membrane B4GALT1 function resulted in the significant inhibition of estrogen-induced proliferation of MCF-7 cells. Considering

  8. RhoE interferes with Rb inactivation and regulates the proliferation and survival of the U87 human glioblastoma cell line

    International Nuclear Information System (INIS)

    Rho GTPases are important regulators of actin cytoskeleton, but they are also involved in cell proliferation, transformation and oncogenesis. One of this proteins, RhoE, inhibits cell proliferation, however the mechanism that regulates this effect remains poorly understood. Therefore, we undertook the present study to determine the role of RhoE in the regulation of cell proliferation. For this purpose we generated an adenovirus system to overexpress RhoE in U87 glioblastoma cells. Our results show that RhoE disrupts actin cytoskeleton organization and inhibits U87 glioblastoma cell proliferation. Importantly, RhoE expressing cells show a reduction in Rb phosphorylation and in cyclin D1 expression. Furthermore, RhoE inhibits ERK activation following serum stimulation of quiescent cells. Based in these findings, we propose that RhoE inhibits ERK activation, thereby decreasing cyclin D1 expression and leading to a reduction in Rb inactivation, and that this mechanism is involved in the RhoE-induced cell growth inhibition. Moreover, we also demonstrate that RhoE induces apoptosis in U87 cells and also in colon carcinoma and melanoma cells. These results indicate that RhoE plays an important role in the regulation of cell proliferation and survival, and suggest that this protein may be considered as an oncosupressor since it is capable to induce apoptosis in several tumor cell lines

  9. E47 regulates hematopoietic stem cell proliferation and energetics but not myeloid lineage restriction

    OpenAIRE

    Yang, Qi; Esplin, Brandt; Borghesi, Lisa

    2011-01-01

    The immune system is replenished by self-renewing hematopoietic stem cells (HSCs) that produce multipotent progenitors (MPPs) with little renewal capacity. E-proteins, the widely expressed basic helix-loop-helix transcription factors, contribute to HSC and MPP activity, but their specific functions remain undefined. Using quantitative in vivo and in vitro approaches, we show that E47 is dispensable for the short-term myeloid differentiation of HSCs but regulates their long-term capabilities. ...

  10. Musashi1 regulates breast tumor cell proliferation and is a prognostic indicator of poor survival

    Directory of Open Access Journals (Sweden)

    Wang Xiao-Yang

    2010-08-01

    Full Text Available Abstract Background Musashi1 (Msi1 is a conserved RNA-binding protein that regulates the Notch and Wnt pathways, and serves as a stem cell marker in the breast and other tissues. It is unknown how Msi1 relates to other breast cancer markers, whether it denotes tumor initiating cells (TICs, and how it affects gene expression and tumor cell survival in breast cancer cells. Results Msi1 expression was analyzed in 20 breast cancer cell lines and in 140 primary breast tumors by western blotting and immunohistochemistry, respectively. Lentivirus RNA interference was used to reduce Msi1 expression in breast cancer cell lines MCF-7 and T47D grown as spheroid cultures and to assess stem cell gene expression and the growth of these cell lines as xenografts. In normal human breast tissue, Msi1 was expressed in 10.6% of myoepithelum and 1.2% of ductal epithelium in the terminal ductal lobular unit (TDLU, whereas, less than 0.05% of ductal epithelium and myoepithelium in large ducts outside the TDLU expressed Msi1. Msi1 was expressed in 55% of the breast cancer cell lines and correlated with ErbB2 expression in 50% of the cell lines. Msi1 was expressed in 68% of primary tumors and in 100% of lymph node metastases, and correlated with 5 year survival. Msi1 was enriched in CD133+ MCF-7 and T47D cells and in spheroid cultures of these cells, and Msi1 'knockdown' (KD with a lentivirus-expressed shRNA decreased the number and size of spheroid colonies. Msi1 KD reduced Notch1, c-Myc, ErbB2 and pERK1/2 expression, and increased p21CIP1 expression, which is consistent with known Msi1 target mRNAs. Msi1 KD also reduced the expression of the somatic and embryonic stem cell markers, CD133, Bmi1, Sox2, Nanog and Oct4. Xenografts of MCF-7 and T47D Msi1 KD cells resulted in a marked reduction of tumor growth, reduced Msi1 and Notch1 expression and increased p21CIP1 expression. Conclusion Msi1 is a negative prognostic indicator of breast cancer patient survival, and is

  11. Akhirin regulates the proliferation and differentiation of neural stem cells in intact and injured mouse spinal cord.

    Science.gov (United States)

    Abdulhaleem, Felemban Athary M; Song, Xiaohong; Kawano, Rie; Uezono, Naohiro; Ito, Ayako; Ahmed, Giasuddin; Hossain, Mahmud; Nakashima, Kinichi; Tanaka, Hideaki; Ohta, Kunimasa

    2015-05-01

    Although the central nervous system is considered a comparatively static tissue with limited cell turnover, cells with stem cell properties have been isolated from most neural tissues. The spinal cord ependymal cells show neural stem cell potential in vitro and in vivo in injured spinal cord. However, very little is known regarding the ependymal niche in the mouse spinal cord. We previously reported that a secreted factor, chick Akhirin, is expressed in the ciliary marginal zone of the eye, where it works as a heterophilic cell-adhesion molecule. Here, we describe a new crucial function for mouse Akhirin (M-AKH) in regulating the proliferation and differentiation of progenitors in the mouse spinal cord. During embryonic spinal cord development, M-AKH is transiently expressed in the central canal ependymal cells, which possess latent neural stem cell properties. Targeted inactivation of the AKH gene in mice causes a reduction in the size of the spinal cord and decreases BrdU incorporation in the spinal cord. Remarkably, the expression patterns of ependymal niche molecules in AKH knockout (AKH-/-) mice are different from those of AKH+/+, both in vitro and in vivo. Furthermore, we provide evidence that AKH expression in the central canal is rapidly upregulated in the injured spinal cord. Taken together, these results indicate that M-AKH plays a crucial role in mouse spinal cord formation by regulating the ependymal niche in the central canal.

  12. miR-125b suppresses the proliferation and migration of osteosarcoma cells through down-regulation of STAT3

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Li-hong; Li, Hui; Li, Jin-ping; Zhong, Hui; Zhang, Han-chon; Chen, Jia [Department of Orthopedics, The Second Xiangya Hospital of Central South University, Changsha 410010 (China); Xiao, Tao, E-mail: xiaotaoxyl@163.com [Department of Orthopedics, The Second Xiangya Hospital of Central South University, Changsha 410010 (China)

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer miR-125b is frequently down-regulated in osteosarcoma samples and human osteosarcoma cell lines. Black-Right-Pointing-Pointer Ectopic restoration of miR-125b suppresses cell proliferation and migration in vitro. Black-Right-Pointing-Pointer STAT3 is the direct and functional downstream target of miR-125b. Black-Right-Pointing-Pointer STAT3 can bind to the promoter region of miR-125b and serves as a transactivator. -- Abstract: There is accumulating evidence that microRNAs are involved in multiple processes in development and tumor progression. Abnormally expressed miR-125b was found to play a fundamental role in several types of cancer; however, whether miR-125b participates in regulating the initiation and progress of osteosarcoma still remains unclear. Here we demonstrate that miR-125b is frequently down-regulated in osteosarcoma samples and human osteosarcoma cell lines. The ectopic restoration of miR-125b expression in human osteosarcoma cells suppresses proliferation and migration in vitro and inhibits tumor formation in vivo. We further identified signal transducer and activator of transcription 3 (STAT3) as the direct and functional downstream target of miR-125b. Interestingly, we discovered that the expression of miR-125b is regulated by STAT3 at the level of transcription. STAT3 binds to the promoter region of miR-125b in vitro and serves as a transactivator. Taken together, our findings point to an important role in the molecular etiology of osteosarcoma and suggest that miR-125b is a potential target in the treatment of osteosarcoma.

  13. 14-3-3σ regulates β-catenin-mediated mouse embryonic stem cell proliferation by sequestering GSK-3β.

    Directory of Open Access Journals (Sweden)

    Tzu-Ching Chang

    Full Text Available BACKGROUND: Pluripotent embryonic stem cells are considered to be an unlimited cell source for tissue regeneration and cell-based therapy. Investigating the molecular mechanism underlying the regulation of embryonic stem cell expansion is thus important. 14-3-3 proteins are implicated in controlling cell division, signaling transduction and survival by interacting with various regulatory proteins. However, the function of 14-3-3 in embryonic stem cell proliferation remains unclear. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we show that all seven 14-3-3 isoforms were detected in mouse embryonic stem cells. Retinoid acid suppressed selectively the expression of 14-3-3σ isoform. Knockdown of 14-3-3σ with siRNA reduced embryonic stem cell proliferation, while only 14-3-3σ transfection increased cell growth and partially rescued retinoid acid-induced growth arrest. Since the growth-enhancing action of 14-3-3σ was abrogated by β-catenin knockdown, we investigated the influence of 14-3-3σ overexpression on β-catenin/GSK-3β. 14-3-3σ bound GSK-3β and increased GSK-3β phosphorylation in a PI-3K/Akt-dependent manner. It disrupted β-catenin binding by the multiprotein destruction complex. 14-3-3σ overexpression attenuated β-catenin phosphorylation and rescued the decline of β-catenin induced by retinoid acid. Furthermore, 14-3-3σ enhanced Wnt3a-induced β-catenin level and GSK-3β phosphorylation. DKK, an inhibitor of Wnt signaling, abolished Wnt3a-induced effect but did not interfere GSK-3β/14-3-3σ binding. SIGNIFICANCE: Our findings show for the first time that 14-3-3σ plays an important role in regulating mouse embryonic stem cell proliferation by binding and sequestering phosphorylated GSK-3β and enhancing Wnt-signaled GSK-3β inactivation. 14-3-3σ is a novel target for embryonic stem cell expansion.

  14. Long non-coding RNA Loc554202 regulates proliferation and migration in breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yongguo, E-mail: 1138303166@qq.com [Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China); Lu, Jianwei, E-mail: jianwei2010077@163.com [Cancer Hospital of Jiangsu Province, Nanjing, Jiangsu (China); Zhou, Jing, E-mail: 2310848@163.com [Department of Oncology, Taizhou People’ Hospital, Taizhou, Jiangsu (China); Tan, Xueming, E-mail: 843039795@qq.com [Department of Gastroenterology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China); He, Ye, E-mail: 2825636@qq.com [Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China); Ding, Jie, E-mail: 9111165@qq.com [Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China); Tian, Yun, E-mail: 1815857@qq.com [Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China); Wang, Li, E-mail: 2376737@qq.com [Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China); Wang, Keming, E-mail: wkmys@sohu.com [Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China)

    2014-04-04

    Highlights: • First, we have shown that upregulated of the Loc554202 in breast cancer tissues. • Second, we demonstrated the function of Loc554202 in breast cancer cell. • Finally, we demonstrated that LOC554202 knockdown could inhibit tumor growth in vivo. - Abstract: Data derived from massive cloning and traditional sequencing methods have revealed that long non-coding RNAs (lncRNA) play important roles in the development and progression of cancer. Although many studies suggest that the lncRNAs have different cellular functions, many of them are not yet to be identified and characterized for the mechanism of their functions. To address this question, we assay the expression level of lncRNAs–Loc554202 in breast cancer tissues and find that Loc554202 is significantly increased compared with normal control, and associated with advanced pathologic stage and tumor size. Moreover, knockdown of Loc554202 decreased breast cancer cell proliferation, induced apoptosis and inhibits migration/invasion in vitro and impeded tumorigenesis in vivo. These data suggest an important role of Loc554202 in breast tumorigenesis.

  15. Co-regulation of the Notch and Wnt signaling pathways promotes supporting cell proliferation and hair cell regeneration in mouse utricles

    Science.gov (United States)

    Wu, Jingfang; Li, Wenyan; Lin, Chen; Chen, Yan; Cheng, Cheng; Sun, Shan; Tang, Mingliang; Chai, Renjie; Li, Huawei

    2016-01-01

    This work sought to determine the crosstalk between the Notch and Wnt signaling pathways in regulating supporting cell (SC) proliferation and hair cell (HC) regeneration in mouse utricles. We cultured postnatal day (P)3 and P60 mouse utricles, damaged the HCs with gentamicin, and treated the utricles with the γ-secretase inhibitor DAPT to inhibit the Notch pathway and with the Wnt agonist QS11 to active the Wnt pathway. We also used Sox2-CreER, Notch1-flox (exon 1), and Catnb-flox (exon 3) transgenic mice to knock out the Notch pathway and activate the Wnt pathway in Sox2+ SCs. Notch inhibition alone increased SC proliferation and HC number in both undamaged and damaged utricles. Wnt activation alone promoted SC proliferation, but the HC number was not significantly increased. Here we demonstrated the cumulative effects of Notch inhibition and Wnt activation in regulating SC proliferation and HC regeneration. Simultaneously inhibiting Notch and overexpressing Wnt led to significantly greater SC proliferation and greater numbers of HCs than manipulating either pathway alone. Similar results were observed in the transgenic mice. This study suggests that the combination of Notch inhibition and Wnt activation can significantly promote SC proliferation and increase the number of regenerated HCs in mouse utricle. PMID:27435629

  16. Up-regulation of CHAF1A, a poor prognostic factor, facilitates cell proliferation of colon cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zehua; Cui, Feifei; Yu, Fudong; Peng, Xiao; Jiang, Tao; Chen, Dawei [Department of General Surgery, Shanghai Jiaotong University Affiliated First People’s Hospital, 85 Wujin Road, Shanghai 200080 (China); Lu, Su [Department of Pathology, Shanghai Jiaotong University Affiliated First People’s Hospital, 85 Wujin Road, Shanghai 200080 (China); Tang, Huamei, E-mail: tanghuamei@gmail.com [Department of Pathology, Shanghai Jiaotong University Affiliated First People’s Hospital, 85 Wujin Road, Shanghai 200080 (China); Peng, Zhihai, E-mail: zhihai.peng@hotmail.com [Department of General Surgery, Shanghai Jiaotong University Affiliated First People’s Hospital, 85 Wujin Road, Shanghai 200080 (China)

    2014-06-27

    Highlights: • We identified that CHAF1A was up-regulated in colon tumor mucosa in TMA. • The expression pattern of CHAF1A was validated with qPCR and western-blot. • CHAF1A overexpression is an independent indicator for poor colon cancer survival. • CHAF1A facilitates cell proliferation of colon cancer both in vitro and in vivo. - Abstract: Deregulation of chromatin assembly factor 1, p150 subunit A (CHAF1A) has recently been reported to be involved in the development of some cancer types. In this study, we identified that the frequency of positive CHAF1A staining in primary tumor mucosa (45.8%, 93 of 203 samples) was significantly elevated compared to that in paired normal mucosa (18.7%, 38 of 203 samples). The increased expression was strongly associated with cancer stage, tumor invasion, and histological grade. The five-year survival rate of patients with CHAF1A-positive tumors was remarkably lower than that of patients with CHAF1A-negative tumors. Colon cancer cells with CHAF1A knockdown exhibited decreased cell growth index, reduction in colony formation ability, elevated cell apoptosis rate as well as impaired colon tumorigenicity in nude mice. Hence, CHAF1A upregulation functions as a poor prognostic indicator of colon cancer, potentially contributing to its progression by mediating cancer cell proliferation.

  17. Up-regulation of CHAF1A, a poor prognostic factor, facilitates cell proliferation of colon cancer

    International Nuclear Information System (INIS)

    Highlights: • We identified that CHAF1A was up-regulated in colon tumor mucosa in TMA. • The expression pattern of CHAF1A was validated with qPCR and western-blot. • CHAF1A overexpression is an independent indicator for poor colon cancer survival. • CHAF1A facilitates cell proliferation of colon cancer both in vitro and in vivo. - Abstract: Deregulation of chromatin assembly factor 1, p150 subunit A (CHAF1A) has recently been reported to be involved in the development of some cancer types. In this study, we identified that the frequency of positive CHAF1A staining in primary tumor mucosa (45.8%, 93 of 203 samples) was significantly elevated compared to that in paired normal mucosa (18.7%, 38 of 203 samples). The increased expression was strongly associated with cancer stage, tumor invasion, and histological grade. The five-year survival rate of patients with CHAF1A-positive tumors was remarkably lower than that of patients with CHAF1A-negative tumors. Colon cancer cells with CHAF1A knockdown exhibited decreased cell growth index, reduction in colony formation ability, elevated cell apoptosis rate as well as impaired colon tumorigenicity in nude mice. Hence, CHAF1A upregulation functions as a poor prognostic indicator of colon cancer, potentially contributing to its progression by mediating cancer cell proliferation

  18. miR-204-5p regulates cell proliferation and metastasis through inhibiting CXCR4 expression in OSCC.

    Science.gov (United States)

    Wang, Xinjuan; Li, Fujun; Zhou, Xiaoli

    2016-08-01

    MicroRNAs (miRNAs) are important small molecules in cancer including oral squamous cell carcinoma (OSCC) which regulate gene expression at post-transcriptional levels. MiR-204-5p acts as a tumor suppressor in some of cancers, but the role of it in OSCC is not known. The aim of this study is to investigate the expression and functional roles of miR-204-5p in OSCC. The results showed that the expression of miR-204-5p was lower in cancer tissues or cells. Next, cell proliferation, cell cycle, migration and invasion were detected. It was found that miR-204-5p could enhance OSCC cell proliferation and metastasis. MiR-204-5p was predicted as a regulatory miRNA of CXCR4 in OSCC, and the data analysis indicated that there was a negatively relationship between miR-204-5p and CXCR4 expression in OSCC tissues from the patients. In a conclusion, our findings suggested that miR-204-5p may function as an inhibitory RNA molecule in OSCC by targeting CXCR4. PMID:27470356

  19. Regulation of Pancreatic Alpha Cell Function and Proliferation by Bone Morphogenetic Protein 4 (BMP4) in vitro

    DEFF Research Database (Denmark)

    Nielsen, Sofie Sylvest; Christensen, Gitte Lund; Holst, Jens Juul;

    2016-01-01

    Increased expression of Bone Morphogenetic Proteins (BMPs) in several tissues is associated with inflammation and Type II Diabetes Mellitus. BMP2 and BMP4 mRNA expression is increased in pancreatic islets from db/db mice and beta cell proliferation and function are inhibited by BMP4. The effect...... incubation with BMP4 in mouse islets, but not in human islets. The percentage of proliferating alpha cells was reduced from 7.3 to 0.2 % in mouse islets incubated with BMP4. Alpha cell proliferation in human islets ranged from 0 to 11.8 %, and BMP4 was found to inhibit proliferation of alpha cells from all...

  20. Regulation of Stem Cell Proliferation and Cell Fate Specification by Wingless/Wnt Signaling Gradients Enriched at Adult Intestinal Compartment Boundaries.

    OpenAIRE

    Ai Tian; Hassina Benchabane; Zhenghan Wang; Yashi Ahmed

    2016-01-01

    Intestinal stem cell (ISC) self-renewal and proliferation are directed by Wnt/β-catenin signaling in mammals, whereas aberrant Wnt pathway activation in ISCs triggers the development of human colorectal carcinoma. Herein, we have utilized the Drosophila midgut, a powerful model for ISC regulation, to elucidate the mechanisms by which Wingless (Wg)/Wnt regulates intestinal homeostasis and development. We provide evidence that the Wg signaling pathway, activation of which peaks at each of the m...

  1. Progesterone regulates the proliferation of breast cancer cells - in vitro evidence.

    Science.gov (United States)

    Azeez, Juberiya M; Sithul, Hima; Hariharan, Indhu; Sreekumar, Sreeja; Prabhakar, Jem; Sreeja, Sreeharshan; Pillai, Madhavan Radhakrishna

    2015-01-01

    Reports state that surgery performed at different phases of the menstrual cycle may significantly affect breast cancer treatment outcome. From previous studies, we identified differentially expressed genes in each menstrual cycle phase by microarray, then subjected them to functional in vitro analyses. Microarray studies disclosed genes that are upregulated in the luteal phase and follicular phase. TOB-1 is a tumor suppressor gene and was expressed exclusively in the luteal phase in our microarray study. Therefore, we further functionally characterized the protein product of TOB-1 in vitro. To our knowledge, no studies have yet been conducted on reactive oxygen species-regulated tumor suppressor interactions in accordance with the biphasic nature of progesterone. This work demonstrates that progesterone can produce reactive oxygen species in MCF-7 cells and that TOB-1 exerts a series of non-genomic interactions that regulate antiproliferative activity by modulating the antioxidant enzyme superoxide dismutase. Furthermore, this study implicates PTEN as an interacting partner for TOB-1, which may regulate the downstream expression of cell cycle control protein p27 via multiple downstream signaling pathways of progesterone through a progesterone receptor, purely in a time- and concentration-dependent manner. These results support the hypothesis that surgery conducted during the luteal phase of the menstrual cycle may facilitate improved patient survival. PMID:26609221

  2. Progesterone regulates the proliferation of breast cancer cells – in vitro evidence

    Science.gov (United States)

    Azeez, Juberiya M; Sithul, Hima; Hariharan, Indhu; Sreekumar, Sreeja; Prabhakar, Jem; Sreeja, Sreeharshan; Pillai, Madhavan Radhakrishna

    2015-01-01

    Reports state that surgery performed at different phases of the menstrual cycle may significantly affect breast cancer treatment outcome. From previous studies, we identified differentially expressed genes in each menstrual cycle phase by microarray, then subjected them to functional in vitro analyses. Microarray studies disclosed genes that are upregulated in the luteal phase and follicular phase. TOB-1 is a tumor suppressor gene and was expressed exclusively in the luteal phase in our microarray study. Therefore, we further functionally characterized the protein product of TOB-1 in vitro. To our knowledge, no studies have yet been conducted on reactive oxygen species-regulated tumor suppressor interactions in accordance with the biphasic nature of progesterone. This work demonstrates that progesterone can produce reactive oxygen species in MCF-7 cells and that TOB-1 exerts a series of non-genomic interactions that regulate antiproliferative activity by modulating the antioxidant enzyme superoxide dismutase. Furthermore, this study implicates PTEN as an interacting partner for TOB-1, which may regulate the downstream expression of cell cycle control protein p27 via multiple downstream signaling pathways of progesterone through a progesterone receptor, purely in a time- and concentration-dependent manner. These results support the hypothesis that surgery conducted during the luteal phase of the menstrual cycle may facilitate improved patient survival. PMID:26609221

  3. The E2F transcription factors: key regulators of cell proliferation

    DEFF Research Database (Denmark)

    Müller, H; Helin, K

    2000-01-01

    Ever since its discovery, the RB-1 gene and the corresponding protein, pRB, have been a focal point of cancer research. The isolation of E2F transcription factors provided the key to our current understanding of RB-1 function in the regulation of the cell cycle and in tumor suppression. It is bec......Ever since its discovery, the RB-1 gene and the corresponding protein, pRB, have been a focal point of cancer research. The isolation of E2F transcription factors provided the key to our current understanding of RB-1 function in the regulation of the cell cycle and in tumor suppression....... It is becoming more and more evident that the regulatory circuits governing the cell cycle are very complex and highly interlinked. Certain aspects of RB-1 function, for instance its role in differentiation, cannot be easily explained by the current models of pRB-E2F interaction. One reason is that pRB has...... targets different from E2F, molecules like MyoD for instance. Another reason may be that we have not completely understood the full complexity of E2F function, itself. In this review, we will try to illuminate the role of E2F in pRB- and p53-mediated tumor suppression pathways with particular emphasis...

  4. MicroRNA-124-3p regulates cell proliferation, invasion, apoptosis, and bioenergetics by targeting PIM1 in astrocytoma.

    Science.gov (United States)

    Deng, Danni; Wang, Lei; Chen, Yao; Li, Bowen; Xue, Lian; Shao, Naiyuan; Wang, Qiang; Xia, Xiwei; Yang, Yilin; Zhi, Feng

    2016-07-01

    The PIM1 protein is an important regulator of cell proliferation, the cell cycle, apoptosis, and metabolism in various human cancers. MicroRNAs (miRNAs) are powerful post-transcriptional gene regulators that function through translational repression or transcript destabilization. Therefore, we aimed to identify whether a close relationship exists between PIM1 and miRNAs. PIM1 protein levels and mRNA levels were significantly upregulated in astrocytoma tissues, indicating the oncogenic role of PIM1 in astrocytoma. Further bioinformatics analysis indicated that miR-124-3p targeted the 3'-UTR of PIM1. We also observed an inverse correlation between the miR-124-3p levels and PIM1 protein or mRNA levels in astrocytoma samples. Next, we experimentally confirmed that miR-124-3p directly recognizes the 3'-UTR of the PIM1 transcript and regulates PIM1 expression at both the protein and mRNA levels. Furthermore, we examined the biological consequences of miR-124-3p targeting PIM1 in vitro. We showed that the repression of PIM1 in astrocytoma cancer cells by miR-124-3p suppressed proliferation, invasion, and aerobic glycolysis and promoted apoptosis. We observed that the restoration or inhibition of PIM1 activity resulted in effects that were similar to those induced by miR-124-3p inhibitors or mimics in cancer cells. Finally, overexpression of PIM1 rescued the inhibitory effects of miR-124-3p. In summary, these findings aid in understanding the tumor-suppressive role of miR-124-3p in astrocytoma pathogenesis through the inhibition of PIM1 translation. PMID:27088547

  5. AB109. Downregulation of tNASP inhibits proliferation through regulating cell cycle-related proteins and inactive ERK/MAPK signal pathway in renal cell carcinoma cells

    Science.gov (United States)

    Fang, Jianzheng; Wang, Hainan; Cheng, Gong; Wang, Shangqian; Deng, Yunfei; Song, Zhen; Xu, Aiming; Liu, Bianjiang; Wang, Zengjun

    2016-01-01

    Objective Nuclear auto-antigenic sperm protein (NASP), initially described as a highly auto-immunogenic testis and sperm-specific protein, is a histone chaperone that is proved to present in all dividing cells. NASP has two splice variants: testicular NASP (tNASP) and somatic form of NASP (sNASP). Only cancer, germ, transformed, and embryonic cells have a high level of expression of the tNASP. Up to now, little has been known about tNASP in renal cell carcinoma (RCC). In the present study, the molecular mechanism of tNASP in RCC was explored. Methods The expression level of tNASP in 16 paired human RCC specimens was determined. Downregulation of tNASP by small interfering RNA (siRNA) was transfected in RCC cell lines. The effect of downregulation of tNASP by siRNA on cell colony formation and proliferation was examined by colony formation assay and CCK-8 assay, cell cycle was analyzed by flow cytometry, and the expression of cyclin D1 and P21 were detected by Western blotting. ERK/MAPK signaling was also analyzed. Results tNASP has a relative high expression level in human RCC tissues. Via upregulation of P21 and downregulation of cyclinD1, silence of tNASP can inhibit cell proliferation, which induces cell cycle arrest. Furthermore, ERK signaling pathway is confirmed to mediate the regulation of cell cycle-related proteins caused by silence of tNASP. Conclusions Our research demonstrates that knockdown of tNASP effectively inhibits the proliferation and causes G1 phase arrest through ERK/MAPK signal pathway.

  6. Progesterone regulates the proliferation of breast cancer cells – in vitro evidence

    Directory of Open Access Journals (Sweden)

    Azeez JM

    2015-11-01

    Full Text Available Juberiya M Azeez,1 Hima Sithul,1 Indhu Hariharan,1 Sreeja Sreekumar,1 Jem Prabhakar,2 Sreeharshan Sreeja,1 Madhavan Radhakrishna Pillai1 1Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, 2Division of Surgical Oncology, Regional Cancer Centre, Thiruvananthapuram, India Abstract: Reports state that surgery performed at different phases of the menstrual cycle may significantly affect breast cancer treatment outcome. From previous studies, we identified differentially expressed genes in each menstrual cycle phase by microarray, then subjected them to functional in vitro analyses. Microarray studies disclosed genes that are upregulated in the luteal phase and follicular phase. TOB-1 is a tumor suppressor gene and was expressed exclusively in the luteal phase in our microarray study. Therefore, we further functionally characterized the protein product of TOB-1 in vitro. To our knowledge, no studies have yet been conducted on reactive oxygen species-regulated tumor suppressor interactions in accordance with the biphasic nature of progesterone. This work demonstrates that progesterone can produce reactive oxygen species in MCF-7 cells and that TOB-1 exerts a series of non-genomic interactions that regulate antiproliferative activity by modulating the antioxidant enzyme superoxide dismutase. Furthermore, this study implicates PTEN as an interacting partner for TOB-1, which may regulate the downstream expression of cell cycle control protein p27 via multiple downstream signaling pathways of progesterone through a progesterone receptor, purely in a time- and concentration-dependent manner. These results support the hypothesis that surgery conducted during the luteal phase of the menstrual cycle may facilitate improved patient survival. Keywords: progesterone, reactive oxygen species, TOB-1, cell growth arrest

  7. Anosmin-1 over-expression regulates oligodendrocyte precursor cell proliferation, migration and myelin sheath thickness.

    Science.gov (United States)

    Murcia-Belmonte, Verónica; Esteban, Pedro F; Martínez-Hernández, José; Gruart, Agnès; Luján, Rafael; Delgado-García, José María; de Castro, Fernando

    2016-04-01

    During development of the central nervous system, anosmin-1 (A1) works as a chemotropic cue contributing to axonal outgrowth and collateralization, as well as modulating the migration of different cell types, fibroblast growth factor receptor 1 (FGFR1) being the main receptor involved in all these events. To further understand the role of A1 during development, we have analysed the over-expression of human A1 in a transgenic mouse line. Compared with control mice during development and in early adulthood, A1 over-expressing transgenic mice showed an enhanced oligodendrocyte precursor cell (OPC) proliferation and a higher number of OPCs in the subventricular zone and in the corpus callosum (CC). The migratory capacity of OPCs from the transgenic mice is increased in vitro due to a higher basal activation of ERK1/2 mediated through FGFR1 and they also produced more myelin basic protein (MBP). In vivo, the over-expression of A1 resulted in an elevated number of mature oligodendrocytes with higher levels of MBP mRNA and protein, as well as increased levels of activation of the ERK1/2 proteins, while electron microscopy revealed thicker myelin sheaths around the axons of the CC in adulthood. Also in the mature CC, the nodes of Ranvier were significantly longer and the conduction velocity of the nerve impulse in vivo was significantly increased in the CC of A1 over-expressing transgenic mice. Altogether, these data confirmed the involvement of A1 in oligodendrogliogenesis and its relevance for myelination. PMID:25662897

  8. Anosmin-1 over-expression regulates oligodendrocyte precursor cell proliferation, migration and myelin sheath thickness.

    Science.gov (United States)

    Murcia-Belmonte, Verónica; Esteban, Pedro F; Martínez-Hernández, José; Gruart, Agnès; Luján, Rafael; Delgado-García, José María; de Castro, Fernando

    2016-04-01

    During development of the central nervous system, anosmin-1 (A1) works as a chemotropic cue contributing to axonal outgrowth and collateralization, as well as modulating the migration of different cell types, fibroblast growth factor receptor 1 (FGFR1) being the main receptor involved in all these events. To further understand the role of A1 during development, we have analysed the over-expression of human A1 in a transgenic mouse line. Compared with control mice during development and in early adulthood, A1 over-expressing transgenic mice showed an enhanced oligodendrocyte precursor cell (OPC) proliferation and a higher number of OPCs in the subventricular zone and in the corpus callosum (CC). The migratory capacity of OPCs from the transgenic mice is increased in vitro due to a higher basal activation of ERK1/2 mediated through FGFR1 and they also produced more myelin basic protein (MBP). In vivo, the over-expression of A1 resulted in an elevated number of mature oligodendrocytes with higher levels of MBP mRNA and protein, as well as increased levels of activation of the ERK1/2 proteins, while electron microscopy revealed thicker myelin sheaths around the axons of the CC in adulthood. Also in the mature CC, the nodes of Ranvier were significantly longer and the conduction velocity of the nerve impulse in vivo was significantly increased in the CC of A1 over-expressing transgenic mice. Altogether, these data confirmed the involvement of A1 in oligodendrogliogenesis and its relevance for myelination.

  9. Interleukin-1β regulates cell proliferation and activity of extracellular matrix remodelling enzymes in cultured primary pig heart cells

    International Nuclear Information System (INIS)

    Research highlights: → Levels of IL-1β are increased in the pig myocardium after infarction. → Cultured pig heart cells possess IL-1 receptors. → IL-1β increases cell proliferation of pig heart cells in-vitro. → IL-1β increases MMP-2 and MMP-9 activity in pig heart cells in-vitro. → IL-1β may be important for tissue remodelling events after myocardial infarction. -- Abstract: After myocardial infarction, elevated levels of interleukins (ILs) are found within the myocardial tissue and IL-1β is considered to play a major role in tissue remodelling events throughout the body. In the study presented, we have established a cell culture model of primary pig heart cells to evaluate the effects of different concentrations of IL-1β on cell proliferation as well as expression and activity of enzymes typically involved in tissue remodelling. Primary pig heart cell cultures were derived from three different animals and stimulated with recombinant pig IL-1β. RNA expression was detected by RT-PCR, protein levels were evaluated by Western blotting, activity of matrix metalloproteinases (MMPs) was quantified by gelatine zymography and cell proliferation was measured using colorimetric MTS assays. Pig heart cells express receptors for IL-1 and application of IL-1β resulted in a dose-dependent increase of cell proliferation (P < 0.05 vs. control; 100 ng/ml; 24 h). Gene expression of caspase-3 was increased by IL-1β (P < 0.05 vs. control; 100 ng/ml; 3 h), and pro-caspase-3 but not active caspase was detected in lysates of pig heart cells by Western blotting. MMP-2 gene expression as well as enzymatic activities of MMP-2 and MMP-9 were increased by IL-1β (P < 0.05 vs. control; 100 ng/ml; 3 h for gene expression, 48 and 72 h for enzymatic activities of MMP-2 and MMP-9, respectively). Our in vitro data suggest that IL-1β plays a major role in the events of tissue remodelling in the heart. Combined with our recently published in vivo data (Meybohm et al., PLoS One

  10. Human mesenchymal stem cell proliferation is regulated by PGE2 through differential activation of cAMP-dependent protein kinase isoforms

    DEFF Research Database (Denmark)

    Kleiveland, Charlotte Ramstad; Kassem, Moustapha; Lea, Tor

    2008-01-01

    . Furthermore, PGE2 treatment leads to enhanced nuclear translocation of beta-catenin, thus influencing cell proliferation. The presence of two PKA isoforms, types I and II, prompted us to investigate their individual contribution in PGE2-mediated regulation of proliferation. Specific activation of PKA type II...... of PGE2 on proliferation of hMSC. We here demonstrate that one of the main control molecules in the Wnt pathway, GSK-3 beta, is phosphorylated at the negative regulatory site ser-9 after treating the cells with PGE2. This phosphorylation is mediated by elevation of cAMP and subsequent activation of PKA...... with synthetic cAMP analogues, resulted in enhancement of proliferation. On the other side, we found that treatment of hMSC with high concentrations of PGE2 inhibited cell proliferation by arresting the cells in G0/G1 phase, an effect we found to be mediated by PKA I. Hence, the two different PKA isoforms seem...

  11. Regulation of MDA-MB-231 cell proliferation by GSK-3β involves epigenetic modifications under high glucose conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Chanchal; Kaur, Jasmine; Tikoo, Kulbhushan, E-mail: tikoo.k@gmail.com

    2014-05-15

    Hyperglycemia is a critical risk factor for development and progression of breast cancer. We have recently reported that high glucose induces phosphorylation of histone H3 at Ser 10 as well as de-phosphorylation of GSK-3β at Ser 9 in MDA-MB-231 cells. Here, we elucidate the mechanism underlying hyperglycemia-induced proliferation in MDA-MB-231 breast cancer cells. We provide evidence that hyperglycemia led to increased DNA methylation and DNMT1 expression in MDA-MB-231 cells. High glucose condition led to significant increase in the expression of PCNA, cyclin D1 and decrease in the expression of PTPN 12, p21 and PTEN. It also induced hypermethylation of DNA at the promoter region of PTPN 12, whereas hypomethylation at Vimentin and Snail. Silencing of GSK-3β by siRNA prevented histone H3 phosphorylation and reduced DNMT1 expression. We show that chromatin obtained after immunoprecipitation with phospho-histone H3 was hypermethylated under high glucose condition, which indicates a cross-talk between DNA methylation and histone H3 phosphorylation. ChIP-qPCR analysis revealed up-regulation of DNMT1 and metastatic genes viz. Vimentin, Snail and MMP-7 by phospho-histone H3, which were down-regulated upon GSK-3β silencing. To the best of our knowledge, this is the first report which shows that interplay between GSK-3β activation, histone H3 phosphorylation and DNA methylation directs proliferation of breast cancer cells. - Highlights: • High glucose induces phosphorylation of histone H3 and dephosphorylation of GSK-3β. • Moreover, hyperglycemia also leads to increased DNA methylation in MDA-MB-231 cells. • Inhibition of GSK-3β prevented histone H3 phosphorylation and reduced DNMT1 levels. • Interplay exists between GSK-3β, histone H3 phosphorylation and DNA methylation.

  12. Argonaute-2 regulates the proliferation of adult stem cells in planarian

    Institute of Scientific and Technical Information of China (English)

    Yong-Qin Li; An Zeng; Xiao-Shuai Han; Chen Wang; Ge Li; Zhen-Chao Zhang; Jian-Yong Wang; Yong-Wen Qin; Qing Jing

    2011-01-01

    Dear Editor,Planarian Schmidtea mediterranea has extraordinary regeneration capabilities due to the abundance of adult stem cells (ASCs) known as neoblasts,which make planarian a powerful in vivo system to study ASC biology [ 1 ].The Argonaute (AGO) family proteins are defined by the presence of Piwi-Argonaute-Zwille (PAZ)) and PIWI domains [2],and mediate silencing via cleavage of mRNAs [3] or inhibition of translation [4].The AGO family proteins fall into two subfamilies,one named after Arabidopsis Argonaute and the other after Drosophila PIWI [5].In most organisms investigated so far,PIWI proteins bind Piwi-interacting RNAs (piRNAs) and are functionally involved in the regulation of germ cells [6,7].By contrast,AGO proteins have distinct roles in the smallRNA-mediated gene silencing pathway.In Drosophila,AGO1 has been illustrated to be engaged in the miRNA pathway,while AGO2 plays an important role in the siRNA-mediated gene regulation [4].

  13. PAK1IP1, a ribosomal stress-induced nucleolar protein, regulates cell proliferation via the p53–MDM2 loop

    OpenAIRE

    Yu, Weishi; Qiu, Zhongwei; Gao, Na; Wang, Liren; Cui, Hengxiang; Qian, Yu; Jiang, Li; Luo, Jian; Yi, Zhengfang; Lu, Hua; Li, Dali; Liu, Mingyao

    2010-01-01

    Cell growth and proliferation are tightly controlled via the regulation of the p53–MDM2 feedback loop in response to various cellular stresses. In this study, we identified a nucleolar protein called PAK1IP1 as another regulator of this loop. PAK1IP1 was induced when cells were treated with chemicals that disturb ribosome biogenesis. Overexpression of PAK1IP1 inhibited cell proliferation by inducing p53-dependent G1 cell-cycle arrest. PAK1IP1 bound to MDM2 and inhibited its ability to ubiquit...

  14. GLI1 is involved in cell cycle regulation and proliferation of NT2 embryonal carcinoma stem cells

    DEFF Research Database (Denmark)

    Vestergaard, Janni; Lind-Thomsen, Allan; Pedersen, Mikkel W.;

    2008-01-01

    of altered HH signaling are interpreted by specific cell types. We have investigated the role of the HH transcription factor glioma-associated oncogene homolog 1 (GLI1) in the human Ntera2=D1 (NT2) embryonal carcinoma stem cell line. The study revealed that expression of GLI1 and its direct transcriptional......1 phase cyclins. In conclusion, our results suggest that GLI1 is involved in cell cycle and proliferation control in the embryonal carcinoma stem cell line NT2....... target Patched (PTCH) is downregulated in the early stages of retinoic acid-induced neuronal differentiation of NT2 cells. To identify transcriptional targets of the HH transcription factor GLI1 in NT2 cells, we performed global expression profiling following GLI1 RNA interference (RNAi). Of the similar...

  15. S100A6 protein negatively regulates CacyBP/SIP-mediated inhibition of gastric cancer cell proliferation and tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Xiaoxuan Ning

    Full Text Available Calcyclin-binding protein (CacyBP/SIP, identified on the basis of its ability to interact with S100 proteins in a calcium-dependent manner, was previously found to inhibit the proliferation and tumorigenesis of gastric cancer cells in our laboratory. Importantly, the effects of S100 proteins on the biological behavior of CacyBP/SIP in gastric cancer remain unclear. Herein, we report the construction of eukaryotic expression vectors for wild-type CacyBP/SIP and a truncated mutant lacking the S100 protein binding domain (CacyBP/SIPΔS100. The expressions of the wild-type and truncated recombinant proteins were demonstrated by transfection of MKN45 gastric cancer cells. Co-immunoprecipitation assays demonstrated interaction between S100A6 and wild-type CacyBP/SIP in MKN45 cells. Removal of the S100 protein binding domain dramatically reduced the affinity of CacyBP/SIP for S100 proteins as indicated by reduced co-immunoprecipitation of S100A6 by CacyBP/SIPΔS100. The MTT assay, FACS assay, clonogenic assay and tumor xenograft experiment were performed to assess the effect of CacyBP/SIP on cell growth and tumorigenesis in vitro and in vivo. Overexpression of CacyBP/SIP inhibited the proliferation and tumorigenesis of MKN45 gastric cancer cells; the proliferation and tumorigenesis rates were even further reduced by the expression of CacyBP/SIPΔS100. We also showed that S100 proteins negatively regulate CacyBP/SIP-mediated inhibition of gastric cancer cell proliferation, through an effect on β-catenin protein expression and transcriptional activation of Tcf/LEF. Although the underlying mechanism of action requires further investigation, this study provides new insight into the interaction between S100 proteins and CacyBP/SIP, which might enrich our knowledge of S100 proteins and be helpful for our understanding of the development of gastric cancer.

  16. Oncogenic NanogP8 expression regulates cell proliferation and migration through the Akt/mTOR signaling pathway in human gastric cancer – SGC-7901cell line

    Directory of Open Access Journals (Sweden)

    Jiang Z

    2016-08-01

    Full Text Available Zheng Jiang, Yao Liu, Chuan Wang Department of Gastroenterology, The First Affiliated Hospital of Chongqing Medical University, Yuzhong District, Chongqing, People’s Republic of China Background: Although elevated expression of NanogP8 has been detected in many human tumor tissues, its role in gastric tumorigenesis remains unclear. Therefore, this study aimed to investigate the function and regulatory mechanism of NanogP8 in gastric cancer.Methods: In this study, NanogP8 cDNA was amplified by real time polymerase chain reaction from the human gastric cancer cell line SGC-7901. The shRNA for RNA interference was established. The NanogP8, pAkt, Akt, pERK, ERK, p-mTOR, and mTOR proteins were detected by using the Western blot assay. Cell viability was evaluated by using the CCK-8 assay. Cell migration and invasion were also examined by using the transwell assay.Results: The results indicated that the NanogP8 overexpression promoted proliferation and migration of SGC-7901 cell line, whereas its ablation exerted opposite effects. Interestingly, NanogP8 activated Akt, a key mediator of survival signals, and without affecting total Akt protein level. The NanogP8-increased gastric cell proliferation was downregulated by Akt inhibition. Our results further showed that increasing NanogP8 expression in human gastric cancer cells promoted cell proliferation by activating the AKT/mTOR pathway and further maintained gastric cell survival.Conclusion: Our findings extend the knowledge regarding the oncogenic functions and proved that the NanogP8 regulates cell proliferation and migration by Akt/mTOR signaling pathway in human gastric cancer SGC-7901cell line. Keywords: NanogP8, cell proliferation, Akt, mTOR

  17. Regulation of cell proliferation by ERK and signal-dependent nuclear translocation of ERK is dependent on Tm5NM1-containing actin filaments.

    Science.gov (United States)

    Schevzov, Galina; Kee, Anthony J; Wang, Bin; Sequeira, Vanessa B; Hook, Jeff; Coombes, Jason D; Lucas, Christine A; Stehn, Justine R; Musgrove, Elizabeth A; Cretu, Alexandra; Assoian, Richard; Fath, Thomas; Hanoch, Tamar; Seger, Rony; Pleines, Irina; Kile, Benjamin T; Hardeman, Edna C; Gunning, Peter W

    2015-07-01

    ERK-regulated cell proliferation requires multiple phosphorylation events catalyzed first by MEK and then by casein kinase 2 (CK2), followed by interaction with importin7 and subsequent nuclear translocation of pERK. We report that genetic manipulation of a core component of the actin filaments of cancer cells, the tropomyosin Tm5NM1, regulates the proliferation of normal cells both in vitro and in vivo. Mouse embryo fibroblasts (MEFs) lacking Tm5NM1, which have reduced proliferative capacity, are insensitive to inhibition of ERK by peptide and small-molecule inhibitors, indicating that ERK is unable to regulate proliferation of these knockout (KO) cells. Treatment of wild-type MEFs with a CK2 inhibitor to block phosphorylation of the nuclear translocation signal in pERK resulted in greatly decreased cell proliferation and a significant reduction in the nuclear translocation of pERK. In contrast, Tm5NM1 KO MEFs, which show reduced nuclear translocation of pERK, were unaffected by inhibition of CK2. This suggested that it is nuclear translocation of CK2-phosphorylated pERK that regulates cell proliferation and this capacity is absent in Tm5NM1 KO cells. Proximity ligation assays confirmed a growth factor-stimulated interaction of pERK with Tm5NM1 and that the interaction of pERK with importin7 is greatly reduced in the Tm5NM1 KO cells.

  18. Vascular Endothelial Growth Factor (VEGF) Bioavailability Regulates Angiogenesis and Intestinal Stem and Progenitor Cell Proliferation during Postnatal Small Intestinal Development

    Science.gov (United States)

    Holoyda, Kathleen A.; Hou, Xiaogang; Fowler, Kathryn L.; Grikscheit, Tracy C.

    2016-01-01

    Background Vascular endothelial growth factor (VEGF) is a highly conserved, master regulatory molecule required for endothelial cell proliferation, organization, migration and branching morphogenesis. Podocoryne carnea and drosophila, which lack endothelial cells and a vascular system, express VEGF homologs, indicating potential roles beyond angiogenesis and vasculogenesis. The role of VEGF in the development and homeostasis of the postnatal small intestine is unknown. We hypothesized regulating VEGF bioavailability in the postnatal small intestine would exhibit effects beyond the vasculature and influence epithelial cell stem/progenitor populations. Methods VEGF mutant mice were created that overexpressed VEGF in the brush border of epithelium via the villin promotor following doxycycline treatment. To decrease VEGF bioavailability, sFlt-1 mutant mice were generated that overexpressed the soluble VEGF receptor sFlt-1 upon doxycycline administration in the intestinal epithelium. Mice were analyzed after 21 days of doxycycline administration. Results Increased VEGF expression was confirmed by RT-qPCR and ELISA in the intestine of the VEGF mutants compared to littermates. The VEGF mutant duodenum demonstrated increased angiogenesis and vascular leak as compared to littermate controls. The VEGF mutant duodenum revealed taller villi and increased Ki-67-positive cells in the transit-amplifying zone with reduced Lgr5 expression. The duodenum of sFlt-1 mutants revealed shorter villi and longer crypts with reduced proliferation in the transit-amplifying zone, reduced expression of Dll1, Bmp4 and VE-cadherin, and increased expression of Sox9 and EphB2. Conclusions Manipulating VEGF bioavailability leads to profound effects on not only the intestinal vasculature, but epithelial stem and progenitor cells in the intestinal crypt. Elucidation of the crosstalk between VEGF signaling in the vasculature, mesenchyme and epithelial stem/progenitor cell populations may direct future

  19. Icariin inhibits oxidized low-density lipoprotein-induced proliferation of vascular smooth muscle cells by suppressing activation of extracellular signal-regulated kinase 1/2 and expression of proliferating cell nuclear antigen.

    Science.gov (United States)

    Hu, Yanwu; Liu, Kai; Yan, Mengtong; Zhang, Yang; Wang, Yadi; Ren, Liqun

    2016-03-01

    Icariin, a flavonoid isolated from the traditional Chinese herbal medicine Epimedium brevicornum Maxim, has been shown to possess anti-inflammatory, anti‑oxidant and anti-atherosclerotic activities in vivo and in vitro. The aim of the present study was to investigate the effects of icariin on oxidized low‑density lipoprotein (ox-LDL)-induced proliferation of vascular smooth muscle cells (VSMCs) and the possible underlying mechanism. VSMCs were cultured and pre‑treated with various concentrations of icariin (0, 10, 20 or 40 µm) prior to stimulation by ox‑LDL (50 µg/ml). Cell proliferation was evaluated by an MTT assay. Flow cytometry was used to study the influence of icariin on the cell cycle. Proliferating cell nuclear antigen (PCNA) expression and phosphorylation levels of extracellular signal-regulated kinase (ERK)1/2 were detected by western blot analysis. The results indicated that icariin significantly inhibited ox‑LDL‑induced proliferation of VSMCs and phosphorylation of ERK1/2. Furthermore, icariin also blocked the ox‑LDL‑induced cell‑cycle progression at G1/S‑interphase and downregulated the expression of PCNA in VSMCs. In conclusion, the present study indicated for the first time that icariin reduced the amount of ox‑LDL‑induced proliferation of VSMCs through suppression of PCNA expression and inactivation of ERK1/2.

  20. Control of cell proliferation by Myc

    DEFF Research Database (Denmark)

    Bouchard, C; Staller, P; Eilers, M

    1998-01-01

    Myc proteins are key regulators of mammalian cell proliferation. They are transcription factors that activate genes as part of a heterodimeric complex with the protein Max. This review summarizes recent progress in understanding how Myc stimulates cell proliferation and how this might contribute...

  1. Cigarette smoke extract promotes proliferation of airway smooth muscle cells in asthmatic rats via regulating cyclin D1 expression

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-yu; XU Yong-jian; LIU Xian-sheng; ZHANG Zhen-xiang

    2010-01-01

    significantly increased compared with that of control group (0.268 0.004) (P <0.01). After the transfection with antisense cyclin D1 plasmid for 30 hours, the ratios of A490 of cyclin D1 protein expression in ASMCs was much lower than in untreated cells (P<0.01). Conclusion CSE may increase the proliferation of ASMCs in asthmatic rats via regulating cyclin D1 expression.

  2. Early peroxisome proliferator-activated receptor gamma regulated genes involved in expansion of pancreatic beta cell mass

    Directory of Open Access Journals (Sweden)

    Vivas Yurena

    2011-12-01

    Full Text Available Abstract Background The progression towards type 2 diabetes depends on the allostatic response of pancreatic beta cells to synthesise and secrete enough insulin to compensate for insulin resistance. The endocrine pancreas is a plastic tissue able to expand or regress in response to the requirements imposed by physiological and pathophysiological states associated to insulin resistance such as pregnancy, obesity or ageing, but the mechanisms mediating beta cell mass expansion in these scenarios are not well defined. We have recently shown that ob/ob mice with genetic ablation of PPARγ2, a mouse model known as the POKO mouse failed to expand its beta cell mass. This phenotype contrasted with the appropriate expansion of the beta cell mass observed in their obese littermate ob/ob mice. Thus, comparison of these models islets particularly at early ages could provide some new insights on early PPARγ dependent transcriptional responses involved in the process of beta cell mass expansion Results Here we have investigated PPARγ dependent transcriptional responses occurring during the early stages of beta cell adaptation to insulin resistance in wild type, ob/ob, PPARγ2 KO and POKO mice. We have identified genes known to regulate both the rate of proliferation and the survival signals of beta cells. Moreover we have also identified new pathways induced in ob/ob islets that remained unchanged in POKO islets, suggesting an important role for PPARγ in maintenance/activation of mechanisms essential for the continued function of the beta cell. Conclusions Our data suggest that the expansion of beta cell mass observed in ob/ob islets is associated with the activation of an immune response that fails to occur in POKO islets. We have also indentified other PPARγ dependent differentially regulated pathways including cholesterol biosynthesis, apoptosis through TGF-β signaling and decreased oxidative phosphorylation.

  3. miR-449 inhibits cell proliferation and is down-regulated in gastric cancer

    Directory of Open Access Journals (Sweden)

    Federspiel Birgitte

    2011-03-01

    Full Text Available Abstract Background Gastric cancer is the fourth most common cancer in the world and the second most prevalent cause of cancer related death. The development of gastric cancer is mainly associated with H. Pylori infection leading to a focus in pathology studies on bacterial and environmental factors, and to a lesser extent on the mechanistic development of the tumour. MicroRNAs are small non-coding RNA molecules involved in post-transcriptional gene regulation. They are found to regulate genes involved in diverse biological functions and alterations in microRNA expression have been linked to the pathogenesis of many malignancies. The current study is focused on identifying microRNAs involved in gastric carcinogenesis and to explore their mechanistic relevance by characterizing their targets. Results Invitrogen NCode miRNA microarrays identified miR-449 to be decreased in 1-year-old Gastrin KO mice and in H. Pylori infected gastric tissues compared to tissues from wild type animals. Growth rate of gastric cell lines over-expressing miR-449 was inhibited by 60% compared to controls. FACS cell cycle analysis of miR-449 over-expressing cells showed a significant increase in the sub-G1 fraction indicative of apoptosis. ß-Gal assays indicated a senescent phenotype of gastric cell lines over-expressing miR-449. Affymetrix 133v2 arrays identified GMNN, MET, CCNE2, SIRT1 and CDK6 as miR-449 targets. Luciferase assays were used to confirm GMNN, MET, CCNE2 and SIRT1 as direct targets. We also show that miR-449 over-expression activated p53 and its downstream target p21 as well as the apoptosis markers cleaved CASP3 and PARP. Importantly, qPCR analyses showed a loss of miR-449 expression in human clinical gastric tumours compared to normal tissues. Conclusions In this study, we document a diminished expression of miR-449 in Gastrin KO mice and further confirmed its loss in human gastric tumours. We investigated the function of miR-449 by identifying its

  4. An Egr-1-specific DNAzyme regulates Egr-1 and proliferating cell nuclear antigen expression in rat vascular smooth muscle cells

    Science.gov (United States)

    ZHANG, JUNBIAO; GUO, CHANGLEI; WANG, RAN; HUANG, LULI; LIANG, WANQIAN; LIU, RUNNAN; SUN, BING

    2013-01-01

    The aim of the present study was to transfect rat aortic smooth muscle cells with an early growth response factor-1 (Egr-1)-specific DNAzyme (ED5), to observe its effect on Egr-1 and proliferating cell nuclear antigen (PCNA) expression and to elucidate the mechanism of ED5-mediated inhibition of vascular smooth muscle cell (VSMC) proliferation. VSMCs in primary culture obtained by tissue block adhesion were identified by morphological observation and α smooth muscle actin (α-SM-actin) immunocytochemistry. The cells were then transfected with ED5 or scrambled ED5 (ED5SCR). The three groups of cells used in the present study were the control group, ED5 group and ED5SCR group. The expression levels of Egr-1 and PCNA protein were detected following transfection by analyzing and calculating the integral optical density value in each group. Primary culture of VSMCs and transfection of ED5 and ED5SCR were successfully accomplished. Following stimulation with 10% fetal calf serum, the Egr-1 protein was expressed most strongly at 1 h and demonstrated a declining trend over time; the expression of PCNA protein began at 4 h, peaked at 24 h and then demonstrated a slightly declining trend over time. Compared with the control group and the ED5SCR group, ED5 inhibited the expression of Egr-1 and PCNA (P<0.05). ED5 was able to inhibit the expression of Egr-1 and PCNA proteins in VSMCs to a certain extent and VSMC proliferation in vitro. DNAzyme gene therapy may be useful as a new method for treating vascular proliferative diseases, including atherosclerosis and restenosis. PMID:23737882

  5. miR-196a targets netrin 4 and regulates cell proliferation and migration of cervical cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jie [Department of Pathology, Liaocheng People’s Hospital, Liaocheng 252000 (China); Zheng, Fangxia [Department of Radiotherapy, Liaocheng People’s Hospital, Liaocheng 252000 (China); Yu, Gang [Department for Disease Control, Tumor Hospital of Liaocheng, Liaocheng 252000 (China); Yin, Yanhua, E-mail: yinyanhuablk@163.com [Department of Pathology, Liaocheng People’s Hospital, Liaocheng 252000 (China); Lu, Qingyang [Department of Pathology, Liaocheng People’s Hospital, Liaocheng 252000 (China)

    2013-11-01

    Highlights: •miR-196a was overexpressed in cervical cancer tissue compared to normal tissue. •miR-196a expression elevated proliferation and migration of cervical cancer cells. •miR-196a inhibited NTN4 expression by binding 3′-UTR region of NTN4 mRNA. •NTN4 inversely correlated with miR-196a expression in cervical tissue and cell line. •NTN4 expression was low in cervical cancer tissue compared to normal tissue. -- Abstract: Recent research has uncovered tumor-suppressive and oncogenic potential of miR-196a in various tumors. However, the expression and mechanism of its function in cervical cancer remains unclear. In this study, we assess relative expression of miR-196a in cervical premalignant lesions, cervical cancer tissues, and four cancer cell lines using quantitative real-time PCR. CaSki and HeLa cells were treated with miR-196a inhibitors, mimics, or pCDNA/miR-196a to investigate the role of miR-196a in cancer cell proliferation and migration. We demonstrated that miR-196a was overexpressed in cervical intraepithelial neoplasia 2–3 and cervical cancer tissue. Moreover, its expression contributes to the proliferation and migration of cervical cancer cells, whereas inhibiting its expression led to a reduction in proliferation and migration. Five candidate targets of miR-196a chosen by computational prediction and Cervical Cancer Gene Database search were measured for their mRNA in both miR-196a-overexpressing and -depleted cancer cells. Only netrin 4 (NTN4) expression displayed an inverse association with miR-196a. Fluorescent reporter assays revealed that miR-196a inhibited NTN4 expression by targeting one binding site in the 3′-untranslated region (3′-UTR) of NTN4 mRNA. Furthermore, qPCR and Western blot assays verified NTN4 expression was downregulated in cervical cancer tissues compared to normal controls, and in vivo mRNA level of NTN4 inversely correlated with miR-196a expression. In summary, our findings provide new insights about the

  6. Laminin isoforms differentially regulate adhesion, spreading, proliferation, and ERK activation of β1 integrin-null cells

    International Nuclear Information System (INIS)

    The presence of many laminin receptors of the β1 integrin family on most cells makes it difficult to define the biological functions of other major laminin receptors such as integrin α6β4 and dystroglycan. We therefore tested the binding of a β1 integrin-null cell line GD25 to four different laminin variants. The cells were shown to produce dystroglycan, which based on affinity chromatography bound to laminin-1, -2/4, and -10/11, but not to laminin-5. The cells also expressed the integrin α6Aβ4A variant. GD25 β1 integrin-null cells are known to bind poorly to laminin-1, but we demonstrate here that these cells bind avidly to laminin-2/4, -5, and -10/11. The initial binding at 20 min to each of these laminins could be inhibited by an integrin α6 antibody, but not by a dystroglycan antibody. Hence, integrin α6Aβ4A of GD25 cells was identified as a major receptor for initial GD25 cell adhesion to three out of four tested laminin isoforms. Remarkably, cell adhesion to laminin-5 failed to promote cell spreading, proliferation, and extracellular signal-regulated kinase (ERK) activation, whereas all these responses occurred in response to adhesion to laminin-2/4 or -10/11. The data establish GD25 cells as useful tools to define the role integrin α6Aβ4A and suggest that laminin isoforms have distinctly different capacities to promote cell adhesion and signaling via integrin α6Aβ4A

  7. Kir2.1 regulates rat smooth muscle cell proliferation, migration, and post-injury carotid neointimal formation.

    Science.gov (United States)

    Qiao, Yong; Tang, Chengchun; Wang, Qingjie; Wang, Dong; Yan, Gaoliang; Zhu, Boqian

    2016-09-01

    Phenotype switching of vascular smooth muscle cells (VSMC) from the contractile type to the synthetic type is a hallmark of vascular disorders such as atherosclerosis and restenosis after angioplasty. Inward rectifier K(+) channel 2.1 (Kir2.1) has been identified in VSMC. However, whether it plays a functional role in regulating cellular transformation remains obscure. In this study, we evaluated the role of Kir2.1 on VSMC proliferation, migration, phenotype switching, and post-injury carotid neointimal formation. Kir2.1 knockdown significantly suppressed platelet-derived growth factor BB-stimulated rat vascular smooth muscle cells (rat-VSMC) proliferation and migration. Deficiency in Kir2.1 contributed to the restoration of smooth muscle α-actin, smooth muscle 22α, and calponin and to a reduction in osteopontin expression in rat-VSMC. Moreover, the in vivo study showed that rat-VSMC switched to proliferative phenotypes and that knockdown of Kir2.1 significantly inhibited neointimal formation after rat carotid injury. Kir2.1 may be a potential therapeutic target in the treatment of cardiovascular diseases, such as atherosclerosis and restenosis following percutaneous coronary intervention. PMID:27387235

  8. DNA damage-induced translocation of S100A11 into the nucleus regulates cell proliferation

    Directory of Open Access Journals (Sweden)

    Ulbricht Tobias

    2010-12-01

    Full Text Available Abstract Background Proteins are able to react in response to distinct stress stimuli by alteration of their subcellular distribution. The stress-responsive protein S100A11 belongs to the family of multifunctional S100 proteins which have been implicated in several key biological processes. Previously, we have shown that S100A11 is directly involved in DNA repair processes at damaged chromatin in the nucleus. To gain further insight into the underlying mechanism subcellular trafficking of S100A11 in response to DNA damage was analyzed. Results We show that DNA damage induces a nucleolin-mediated translocation of S100A11 from the cytoplasm into the nucleus. This translocation is impeded by inhibition of the phosphorylation activity of PKCα. Translocation of S100A11 into the nucleus correlates with an increased cellular p21 protein level. Depletion of nucleolin by siRNA severely impairs translocation of S100A11 into the nucleus resulting in a decreased p21 protein level. Additionally, cells lacking nucleolin showed a reduced colony forming capacity. Conclusions These observations suggest that regulation of the subcellular distribution of S100A11 plays an important role in the DNA damage response and p21-mediated cell cycle control.

  9. Myeloid cell-derived reactive oxygen species externally regulate the proliferation of myeloid progenitors in emergency granulopoiesis

    Science.gov (United States)

    Kwak, Hyun-Jeong; Liu, Peng; Bajrami, Besnik; Xu, Yuanfu; Park, Shin-Young; Nombela-Arrieta, Cesar; Mondal, Subhanjan; Sun, Yan; Zhu, Haiyan; Chai, Li; Silberstein, Leslie E.; Cheng, Tao; Luo, Hongbo R.

    2015-01-01

    Summary The cellular mechanisms controlling infection-induced emergency granulopoiesis are poorly defined. Here we found that reactive oxygen species (ROS) concentrations in the bone marrow (BM) were elevated during acute infection in a phagocytic NADPH oxidase-dependent manner in myeloid cells. Gr1+ myeloid cells were uniformly distributed in the BM, and all c-Kit+ progenitor cells were adjacent to Gr1+ myeloid cells. Inflammation-induced ROS production in the BM played a critical role in myeloid progenitor expansion during emergency granulopoiesis. ROS elicited oxidation and deactivation of phosphatase and tensin homolog (PTEN), resulting in up-regulation of PtdIns(3,4,5)P3 signaling in BM myeloid progenitors. We further revealed that BM myeloid cell-produced ROS stimulated proliferation of myeloid progenitors via a paracrine mechanism. Taken together, our results establish that phagocytic NADPH oxidase-mediated ROS production by BM myeloid cells plays a critical role in mediating emergency granulopoiesis during acute infection. PMID:25579427

  10. Protease-activated receptor-1 negatively regulates proliferation of neural stem/progenitor cells derived from the hippocampal dentate gyrus of the adult mouse.

    Science.gov (United States)

    Tanaka, Masayuki; Yoneyama, Masanori; Shiba, Tatsuo; Yamaguchi, Taro; Ogita, Kiyokazu

    2016-07-01

    Thrombin-activated protease-activated receptor (PAR)-1 regulates the proliferation of neural cells following brain injury. To elucidate the involvement of PAR-1 in the neurogenesis that occurs in the adult hippocampus, we examined whether PAR-1 regulated the proliferation of neural stem/progenitor cells (NPCs) derived from the murine hippocampal dentate gyrus. NPC cultures expressed PAR-1 protein and mRNA encoding all subtypes of PAR. Direct exposure of the cells to thrombin dramatically attenuated the cell proliferation without causing cell damage. This thrombin-induced attenuation was almost completely abolished by the PAR antagonist RWJ 56110, as well as by dabigatran and 4-(2-aminoethyl)benzenesulfonyl fluoride (AEBSF), which are selective and non-selective thrombin inhibitors, respectively. Expectedly, the PAR-1 agonist peptide (AP) SFLLR-NH2 also attenuated the cell proliferation. The cell proliferation was not affected by the PAR-1 negative control peptide RLLFT-NH2, which is an inactive peptide for PAR-1. Independently, we determined the effect of in vivo treatment with AEBSF or AP on hippocampal neurogenesis in the adult mouse. The administration of AEBSF, but not that of AP, significantly increased the number of newly-generated cells in the hippocampal subgranular zone. These data suggest that PAR-1 negatively regulated adult neurogenesis in the hippocampus by inhibiting the proliferative activity of the NPCs. PMID:27426918

  11. Hepatocyte growth factor activator inhibitor-1 is induced by bone morphogenetic proteins and regulates proliferation and cell fate of neural progenitor cells.

    Directory of Open Access Journals (Sweden)

    Raili Koivuniemi

    Full Text Available BACKGROUND: Neural progenitor cells (NPCs in the developing neuroepithelium are regulated by intrinsic and extrinsic factors. There is evidence that NPCs form a self-supporting niche for cell maintenance and proliferation. However, molecular interactions and cell-cell contacts and the microenvironment within the neuroepithelium are largely unknown. We hypothesized that cellular proteases especially those associated with the cell surface of NPCs play a role in regulation of progenitor cells in the brain. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we show that NPCs, isolated from striatal anlage of developing rat brain, express hepatocyte growth factor activator inhibitor-1 and -2 (HAI-1 and HAI-2 that are cell surface-linked serine protease inhibitors. In addition, radial glia cells derived from mouse embryonic stem cells also express HAI-1 and HAI-2. To study the functional significance of HAI-1 and HAI-2 in progenitor cells, we modulated their levels using expression plasmids or silencing RNA (siRNA transfected into the NPCs. Data showed that overexpression of HAI-1 or HAI-2 decreased cell proliferation of cultured NPCs, whilst their siRNAs had opposite effects. HAI-1 also influenced NPC differentiation by increasing the number of glial fibrillary acidic protein (GFAP expressing cells in the culture. Expression of HAI-1 in vivo decreased cell proliferation in developing neuroepithelium in E15 old animals and promoted astrocyte cell differentiation in neonatal animals. Studying the regulation of HAI-1, we observed that Bone morphogenetic protein-2 (BMP-2 and BMP-4 increased HAI-1 levels in the NPCs. Experiments using HAI-1-siRNA showed that these BMPs act on the NPCs partly in a HAI-1-dependent manner. CONCLUSIONS: This study shows that the cell-surface serine protease inhibitors, HAI-1 and HAI-2 influence proliferation and cell fate of NPCs and their expression levels are linked to BMP signaling. Modulation of the levels and actions of HAI-1

  12. Epigenetic transcriptional regulation of the growth arrest-specific gene 1 (Gas1 in hepatic cell proliferation at mononucleosomal resolution.

    Directory of Open Access Journals (Sweden)

    Natalia Sacilotto

    Full Text Available BACKGROUND: Gas1 (growth arrest-specific 1 gene is known to inhibit cell proliferation in a variety of models, but its possible implication in regulating quiescence in adult tissues has not been examined to date. The knowledge of how Gas1 is regulated in quiescence may contribute to understand the deregulation occurring in neoplastic diseases. METHODOLOGY/PRINCIPAL FINDINGS: Gas1 expression has been studied in quiescent murine liver and during the naturally synchronized cell proliferation after partial hepatectomy. Chromatin immunoprecipitation at nucleosomal resolution (Nuc-ChIP has been used to carry out the study preserving the in vivo conditions. Transcription has been assessed at real time by quantifying the presence of RNA polymerase II in coding regions (RNApol-ChIP. It has been found that Gas1 is expressed not only in quiescent liver but also at the cell cycle G(1/S transition. The latter expression peak had not been previously reported. Two nucleosomes, flanking a nucleosome-free region, are positioned close to the transcription start site. Both nucleosomes slide in going from the active to the inactive state and vice versa. Nuc-ChIP analysis of the acquisition of histone epigenetic marks show distinctive features in both active states: H3K9ac and H3K4me2 are characteristic of transcription in G(0 and H4R3me2 in G(1/S transition. Sequential-ChIP analysis revealed that the "repressing" mark H3K9me2 colocalize with several "activating" marks at nucleosome N-1 when Gas1 is actively transcribed suggesting a greater plasticity of epigenetic marks than proposed until now. The recruitment of chromatin-remodeling or modifying complexes also displayed distinct characteristics in quiescence and the G(1/S transition. CONCLUSIONS/SIGNIFICANCE: The finding that Gas1 is transcribed at the G(1/S transition suggests that the gene may exert a novel function during cell proliferation. Transcription of this gene is modulated by specific "activating" and

  13. Increased expression of long noncoding RNA TUG1 predicts a poor prognosis of gastric cancer and regulates cell proliferation by epigenetically silencing of p57

    OpenAIRE

    Zhang, E; He, X; Yin, D; Han, L.; Qiu, M; XU, T; Xia, R; Xu, L.; Yin, R; De, W

    2016-01-01

    Recent evidence highlights long noncoding RNAs (lncRNAs) as crucial regulators of cancer biology that contribute to tumorigenesis. LncRNA TUG1 was initially detected in a genomic screen for genes upregulated in response to taurine treatment in developing mouse retinal cells. Our previous study showed that TUG1 could affect cell proliferation through epigenetically regulating HOXB7 in human non-small cell lung cancer. However, the clinical significance and potential role of TUG1 in GC remains ...

  14. TTYH2, a human homologue of the Drosophila melanogaster gene tweety, is up-regulated in colon carcinoma and involved in cell proliferation and cell aggregation

    Institute of Scientific and Technical Information of China (English)

    Yuji Toiyama; Akira Mizoguchi; Kazushi Kimura; Junichirou Hiro; Yasuhiro Inoue; Tomonari Tutumi; Chikao Miki; Masato Kusunoki

    2007-01-01

    AIM: To investigate the expression patterns of TTYH2 in the human colon cancer and colon cancer cell lines and to evaluate the inhibitory effect of small interfering RNA (siRIMA) on the expression of TTYH2 in colon cancer cell lines.METHODS: We investigated the expression patterns of TTYH2 in colon cancer, adjacent non-tumorous colon mucosa, and cancer cell lines (DLD-1, caco-2, and Lovo) by RT-PCR. Furthermore, a siRNA plasmid expression vector against TTYH2 was constructed and transfected into DLD-1 and Caco-2 with LipofectamineTM 2000. The down regulation of TTYH2 expression was detected by RT-PCR and the role of siRNA in inducing cell proliferation and cell aggregation was evaluated by MTT and aggregation assay.RESULTS: TTYH2 gene expression in colon cancer tissue was significantly up-regulated compared with normal colonic mucosa (1.23 ± 0.404 vs 0.655 ± 0.373, P=0.0103). Colon cancer derived cell lines including DLD-1, Caco-2, and Lovo also expressed high levels of TTYH2. In contrast, transfection with siRNA-TTYH2 significantly inhibited both proliferation and scattering of these cancer cell lines.CONCLUSION: The present work demonstrates, for the first time, that the TTYH2 gene expression is significantly up-regulated in colon cancer. The TTYH2 gene may play an important role in regulating both proliferating and metastatic potentials of colorectal cancer.

  15. Gene Expression Profiling Identifies Cell Proliferation and Inflammation as the Predominant Pathways Regulated by Aryl Hydrocarbon Receptor in Primary Human Fetal Lung Cells Exposed to Hyperoxia.

    Science.gov (United States)

    Shivanna, Binoy; Maity, Suman; Zhang, Shaojie; Patel, Ananddeep; Jiang, Weiwu; Wang, Lihua; Welty, Stephen E; Belmont, John; Coarfa, Cristian; Moorthy, Bhagavatula

    2016-07-01

    Exposure to hyperoxia contributes to the development of bronchopulmonary dysplasia (BPD) in premature infants. We observed that aryl hydrocarbon receptor (AhR) signaling protects newborn mice and primary fetal human pulmonary microvascular endothelial cells (HPMECs) against hyperoxic injury. Additionally, a recent genome-wide transcriptome study in a newborn mouse model of BPD identified AhR as a key regulator of hyperoxia-induced gene dysregulation. Whether the AhR similarly deregulates genes in HPMEC is unknown. Therefore, the objective of this study was to characterize transcriptome level gene expression profile in AhR-sufficient and -deficient HPMEC exposed to normoxic and hyperoxic conditions. Global gene expression profiling was performed using Illumina microarray platform and selected genes were validated by real-time RT-PCR. AhR gene expression and hyperoxia independently affected the expression of 540 and 593 genes, respectively. Two-way ANOVA further identified 85 genes that were affected by an interaction between AhR expression and exposure to hyperoxia. Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology, and Reactome pathway analysis identified cell proliferation, immune function, cytokine signaling, and organ development as the major pathways affected in AhR-deficient cells. The biological processes that were significantly enriched by hyperoxia included metabolic process, stress response, signal transduction, cell cycle, and immune regulation. Cell cycle was the predominant pathway affected by the combined effect of AhR knockdown and hyperoxia. Functional analysis of cell cycle showed that AhR-deficient cells had decreased proliferation compared with AhR-sufficient cells. These findings suggest that AhR modulates hyperoxic lung injury by regulating the genes that are necessary for cell proliferation and inflammation. PMID:27103661

  16. HERG K+ channels expression in gastric cancers and analysis of its regulation in tumor cell proliferation and apoptosis

    Institute of Scientific and Technical Information of China (English)

    Qing Lü; Huiyu Li; Xiaoming Lu; Guobin Wang

    2009-01-01

    Objective: To investigate the expression of herg 1 gene in tumor tissues from gastric carcinomas and gastric carcinoma cell lines, and study the relationship between HERG K+ channel expressions and tumor cell proliferation and apoptosis. Methods: RT-PCR and PCR assays were used to detect the expression of herg 1 gene in 64 gastric carcinomas and the gastric cancer cell line SGC-7901. Blocking the HERG K+ channels was used to evaluate their effects on tumor cell proliferation and apoptosis. Results:The statistically significant expression of herg 1 gene was detected in all the gastric cancers and SGC-7901 cells, but not in normal tissues. The HERG K+ channel blocker, E-4031, increased the cell population in G0/G1 (P<0.05) and the number of apoptotic tumor cells(P<0.05). Conclusion: HERG K+ channels were expressed in all gastric carcinomas tested and these channels appear to modulate tumor cell proliferation and apoptosis.

  17. Dexamethasone suppresses DU145 cell proliferation and cell cycle through inhibition of the extracellular signal-regulated kinase 1/2 pathway and cyclin D1 expression

    Institute of Scientific and Technical Information of China (English)

    Qing-Zhen Gao; Jia-Ju Lu; Zi-Dong Liu; Hui Zhang; Shao-Mei Wang; He Xu

    2008-01-01

    Aim: To determine the mechanisms of glucocorticoids in inhibiting advanced prostate cancer growth. Methods: The cell proliferation and cell cycle of prostate cancer DU145 cells following dexamethasone treatment were determined by proliferation assay and fluorescence-activated cell sorter. Western blot analysis was carried out to evaluate the effects of dexamethasone on phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and expression of cyclin D1 in DU145 cells with or without glucocorticoid receptor (GR) antagonist RU486. Reverse transcription- polymerase chain reaction verified the expression of GR mRNA in DU145 cells. Results: Dexamethasone signifi- cantly inhibited DU145 cell proliferation at the G0/G1 phase. Western blot analysis showed a dramatic reduction of ERK1/2 activity and cyclin D1 expression in dexamethasone-treated cells. The decreased phosphorylation of ERK1/2 in dexamethasone-treated cells was attenuated by GR blockade. Additionally, the effects of dexamethasone in inhibiting cyclin D1 expression were altered by GR blockade. Conclusion: Dexamethasone suppresses DU 145 cell prolifera- tion and cell cycle, and the underlying mechanisms are through the inhibition of phosphorylation of ERK1/2 and cyclin D1 expression. The inhibition of ERK1/2 phosphorylation and cyclin D1 expression is attenuated by GR blockade, suggesting that GR regulates ERK1/2 and cyclin D 1 pathways. These observations suggest that dexamethasone has a potential clinical application in prostate cancer therapy. (Asian JAndrol 2008 Jul; 10: 635-641)

  18. Oncogenic NanogP8 expression regulates cell proliferation and migration through the Akt/mTOR signaling pathway in human gastric cancer – SGC-7901cell line

    Science.gov (United States)

    Jiang, Zheng; Liu, Yao; Wang, Chuan

    2016-01-01

    Background Although elevated expression of NanogP8 has been detected in many human tumor tissues, its role in gastric tumorigenesis remains unclear. Therefore, this study aimed to investigate the function and regulatory mechanism of NanogP8 in gastric cancer. Methods In this study, NanogP8 cDNA was amplified by real time polymerase chain reaction from the human gastric cancer cell line SGC-7901. The shRNA for RNA interference was established. The NanogP8, pAkt, Akt, pERK, ERK, p-mTOR, and mTOR proteins were detected by using the Western blot assay. Cell viability was evaluated by using the CCK-8 assay. Cell migration and invasion were also examined by using the transwell assay. Results The results indicated that the NanogP8 overexpression promoted proliferation and migration of SGC-7901 cell line, whereas its ablation exerted opposite effects. Interestingly, NanogP8 activated Akt, a key mediator of survival signals, and without affecting total Akt protein level. The NanogP8-increased gastric cell proliferation was downregulated by Akt inhibition. Our results further showed that increasing NanogP8 expression in human gastric cancer cells promoted cell proliferation by activating the AKT/mTOR pathway and further maintained gastric cell survival. Conclusion Our findings extend the knowledge regarding the oncogenic functions and proved that the NanogP8 regulates cell proliferation and migration by Akt/mTOR signaling pathway in human gastric cancer SGC-7901cell line.

  19. MiR-18a regulates the proliferation, migration and invasion of human glioblastoma cell by targeting neogenin

    International Nuclear Information System (INIS)

    MiR-17-92 cluster has recently been reported as an oncogene in some tumors. However, the association of miR-18a, an important member of this cluster, with glioblastoma remains unknown. Therefore, this study aims to investigate the expression of miR-18a in glioblastoma and its role in biological behavior of U87 and U251 human glioblastoma cell lines. Quantitative RT-PCR results showed that miR-18a was highly expressed in glioblastoma tissues and U87 and U251 cell lines compared with that in human brain tissues and primary normal human astrocytes, and the expression levels were increased along with the rising pathological grades of glioblastoma. Neogenin was identified as the target gene of miR-18a by dual-luciferase reporter assays. RT-PCR and western blot results showed that its expression levels were decreased along with the rising pathological grades of glioblastoma. Inhibition of miR-18a expression was established by transfecting exogenous miR-18a inhibitor into U87 and U251 cells, and its effects on the biological behavior of glioblastoma cells were studied using CCK-8 assay, transwell assay and flow cytometry. Inhibition of miR-18a expression in U87 and U251 cells significantly up-regulated neogenin, and dramatically suppressed the abilities of cell proliferation, migration and invasion, induced cell cycle arrest and promoted cellular apoptosis. Collectively, these results suggest that miR-18a may regulate biological behavior of human glioblastoma cells by targeting neogenin, and miR-18a can serve as a potential target in the treatment of glioblastoma. - Highlights: • MiR-18a was highly expressed in glioblastoma tissues and U87 and U251 cell lines. • Neogenin was identified as the target gene of miR-18a. • Neogenin expressions were decreased along with the rising pathological grades of glioblastoma. • Inhibition of miR-18a suppressed biological behavior of glioma cells by up-regulating neogenin

  20. MiR-18a regulates the proliferation, migration and invasion of human glioblastoma cell by targeting neogenin

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yichen, E-mail: jeff200064017@163.com [Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Wang, Ping, E-mail: pingwang8000@163.com [Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001 (China); Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001 (China); Zhao, Wei, E-mail: 15669746@qq.com [Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001 (China); Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001 (China); Yao, Yilong, E-mail: yaoyilong_322@163.com [Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Liu, Xiaobai, E-mail: paganizonda1991@qq.com [The 96th Class, 7-year Program, China Medical University, Shenyang, Liaoning Province 110001 (China); Ma, Jun, E-mail: majun_724@163.com [Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001 (China); Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001 (China); Xue, Yixue, E-mail: xueyixue888@163.com [Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001 (China); Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001 (China); Liu, Yunhui, E-mail: liuyh@sj-hospital.org [Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004 (China)

    2014-05-15

    MiR-17-92 cluster has recently been reported as an oncogene in some tumors. However, the association of miR-18a, an important member of this cluster, with glioblastoma remains unknown. Therefore, this study aims to investigate the expression of miR-18a in glioblastoma and its role in biological behavior of U87 and U251 human glioblastoma cell lines. Quantitative RT-PCR results showed that miR-18a was highly expressed in glioblastoma tissues and U87 and U251 cell lines compared with that in human brain tissues and primary normal human astrocytes, and the expression levels were increased along with the rising pathological grades of glioblastoma. Neogenin was identified as the target gene of miR-18a by dual-luciferase reporter assays. RT-PCR and western blot results showed that its expression levels were decreased along with the rising pathological grades of glioblastoma. Inhibition of miR-18a expression was established by transfecting exogenous miR-18a inhibitor into U87 and U251 cells, and its effects on the biological behavior of glioblastoma cells were studied using CCK-8 assay, transwell assay and flow cytometry. Inhibition of miR-18a expression in U87 and U251 cells significantly up-regulated neogenin, and dramatically suppressed the abilities of cell proliferation, migration and invasion, induced cell cycle arrest and promoted cellular apoptosis. Collectively, these results suggest that miR-18a may regulate biological behavior of human glioblastoma cells by targeting neogenin, and miR-18a can serve as a potential target in the treatment of glioblastoma. - Highlights: • MiR-18a was highly expressed in glioblastoma tissues and U87 and U251 cell lines. • Neogenin was identified as the target gene of miR-18a. • Neogenin expressions were decreased along with the rising pathological grades of glioblastoma. • Inhibition of miR-18a suppressed biological behavior of glioma cells by up-regulating neogenin.

  1. GSK3β Regulates Milk Synthesis in and Proliferation of Dairy Cow Mammary Epithelial Cells via the mTOR/S6K1 Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Xia Zhang

    2014-07-01

    Full Text Available Glycogen synthase kinase 3 (GSK3 is a serine/threonine kinase, whose activity is inhibited by AKT phosphorylation. This inhibitory phosphorylation of GSK3β can in turn play a regulatory role through phosphorylation of several proteins (such as mTOR, elF2B to promote protein synthesis. mTOR is a key regulator in protein synthesis and cell proliferation, and recent studies have shown that both GSK3β and mTORC1 can regulate SREBP1 to promote fat synthesis. Thus far, however, the cross talk between GSK3β and the mTOR pathway in the regulation of milk synthesis and associated cell proliferation is not well understood. In this study the interrelationship between GSK3β and the mTOR/S6K1 signaling pathway leading to milk synthesis and proliferation of dairy cow mammary epithelial cells (DCMECs was analyzed using techniques including GSK3β overexpression by transfection, GSK3β inhibition, mTOR inhibition and methionine stimulation. The analyses revealed that GSK3β represses the mTOR/S6K1 pathway leading to milk synthesis and cell proliferation of DCMECs, whereas GSK3β phosphorylation enhances this pathway. Conversely, the activated mTOR/S6K1 signaling pathway downregulates GSK3β expression but enhances GSK3β phosphorylation to increase milk synthesis and cell proliferation, whereas inhibition of mTOR leads to upregulation of GSK3β and repression of GSK3β phosphorylation, which in turn decreases milk synthesis, and cell proliferation. These findings indicate that GSK3β and phosphorylated GSK3β regulate milk synthesis and proliferation of DCMECs via the mTOR/S6K1 signaling pathway. These findings provide new insight into the mechanisms of milk synthesis.

  2. miR-483 is Down-Regulated in Polycystic Ovarian Syndrome and Inhibits KGN Cell Proliferation via Targeting Insulin-Like Growth Factor 1 (IGF1)

    Science.gov (United States)

    Xiang, Yungai; Song, Yuxia; Li, Yan; Zhao, Dongmei; Ma, Liying; Tan, Li

    2016-01-01

    Background Polycystic ovarian syndrome (PCOS) is a common metabolic disorder in premenopausal woman, characterized by hyperandrogenism, oligoanovulation, and insulin resistance. microRNAs play pivotal roles in regulating key factors of PCOS. However, relevant research remains limited. This study aimed to reveal the role and potential mechanism of miR-483 in PCOS. Material/Methods PCOS patients (n=20) were recruited for detecting miR-483 expression in lesion and normal ovary cortex. Human granulosa-like tumor cell line KGN was used to alter miR-483 expression by cell transfection. Cell viability and proliferation were analyzed by MTT assay and colony formation assay, and cell cycle was detected by flow cytometry. Interaction between miR-483 and IGF1 was verified by luciferase reporter assay. KGN cells were further treated by insulin to investigate the relationship between miR-483 and insulin. Results miR-483 was significantly down-regulated in lesion ovary cortex from PCOS patients (P<0.001). In KGN cells, overexpression of miR-483 inhibited cell viability and proliferation, and induced cell cycle arrest. miR-483 also inhibited CCNB1, CCND1, and CDK2. miR-483 sponge induced the opposite effects. miR-483 directly targeted IGF1 3′UTR, and IGF1 promoted KGN cell proliferation and reversed miR-483-inhibited cell viability. Insulin treatment in KGN cells inhibited miR-483, and promoted IGF1 and cell proliferation. Conclusions These results suggest that miR-483 is a PCOS suppressor inhibiting cell proliferation, possibly via targeting IGF1, and that it is involved in insulin-induced cell proliferation. miR-483 is a potential alternative for diagnosing and treating PCOS. PMID:27662007

  3. Evidence for a role of Collapsin response mediator protein-2 in signaling pathways that regulate the proliferation of non-neuronal cells

    International Nuclear Information System (INIS)

    Collapsin response mediator protein-2 or Crmp-2 plays a critical role in the establishment of neuronal polarity. In this study, we present evidence that apart from its functions in neurodevelopment, Crmp-2 is also involved in pathways that regulate the proliferation of non-neuronal cells through its phosphorylation by regulatory proteins. We show that Crmp-2 undergoes dynamic phosphorylation changes in response to contact inhibition-induced quiescence and that hyperphosphorylation of Crmp-2 occurs in a tumor. We further suggest that de-regulation of Crmp-2 phosphorylation levels at certain amino acid residues may lead to aberrant cell proliferation and consequently, tumorigenesis

  4. The long non-coding RNA HOTAIR promotes the proliferation of serous ovarian cancer cells through the regulation of cell cycle arrest and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Jun-jun [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China); Wang, Yan [Cancer Institute, Fudan University Shanghai Cancer Center, 270 Dong' an Road, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, 130 Dong' an Road, Shanghai 200032 (China); Ding, Jing-xin; Jin, Hong-yan [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China); Yang, Gong, E-mail: yanggong@fudan.edu.cn [Cancer Institute, Fudan University Shanghai Cancer Center, 270 Dong' an Road, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, 130 Dong' an Road, Shanghai 200032 (China); Hua, Ke-qin, E-mail: huakeqin@126.com [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China)

    2015-05-01

    HOX transcript antisense RNA (HOTAIR) is a well-known long non-coding RNA (lncRNA) whose dysregulation correlates with poor prognosis and malignant progression in many forms of cancer. Here, we investigate the expression pattern, clinical significance, and biological function of HOTAIR in serous ovarian cancer (SOC). Clinically, we found that HOTAIR levels were overexpressed in SOC tissues compared with normal controls and that HOTAIR overexpression was correlated with an advanced FIGO stage and a high histological grade. Multivariate analysis revealed that HOTAIR is an independent prognostic factor for predicting overall survival in SOC patients. We demonstrated that HOTAIR silencing inhibited A2780 and OVCA429 SOC cell proliferation in vitro and that the anti-proliferative effects of HOTAIR silencing also occurred in vivo. Further investigation into the mechanisms responsible for the growth inhibitory effects by HOTAIR silencing revealed that its knockdown resulted in the induction of cell cycle arrest and apoptosis through certain cell cycle-related and apoptosis-related proteins. Together, these results highlight a critical role of HOTAIR in SOC cell proliferation and contribute to a better understanding of the importance of dysregulated lncRNAs in SOC progression. - Highlights: • HOTAIR overexpression correlates with an aggressive tumour phenotype and a poor prognosis in SOC. • HOTAIR promotes SOC cell proliferation both in vitro and in vivo. • The proliferative role of HOTAIR is associated with regulation of the cell cycle and apoptosis.

  5. MicroRNA-100 regulates SW620 colorectal cancer cell proliferation and invasion by targeting RAP1B.

    Science.gov (United States)

    Peng, Hui; Luo, Jun; Hao, Hu; Hu, Jun; Xie, Shang-Kui; Ren, Donglin; Rao, Benqiang

    2014-05-01

    MicroRNAs (miRNAs) have been demonstrated to play important roles in tumorigenesis of human cancer. Fewer studies have explored the roles of miR-100 on human colorectal cancer cell proliferation and invasion. In this study, we utilized real-time PCR to verify whether miR-100 was downregulated in human colorectal cancer tissues compared with matched adjacent normal tissues. Functional studies demonstrated that ectopic expression of miR-100 inhabits cell growth and invasion and induce apoptosis, whereas knockdown of miR-100 yielded the reverse phenotype. Mechanistic studies reveal that miR-100 repressed the activity of a reporter gene fused to the 3'-untranslated region (3'-UTR) of RAP1B, whereas miR-100 silencing upregulated the expression of the reporter gene. Furthermore, we also detected that RAP1B mRNA was inversely expressed with miR-100 in colorectal cancer tissues. These data indicate that the miR-100 plays a tumor suppressor role by regulating colorectal cancer cell growth and invasion phenotype, and could serve as a potential maker for colorectal cancer therapy. PMID:24626817

  6. MicroRNA-638 inhibits cell proliferation, invasion and regulates cell cycle by targeting tetraspanin 1 in human colorectal carcinoma

    Science.gov (United States)

    Wang, Qifeng; Song, Mingxu; Yin, Yuan; Zhang, Binbin; Ni, Shujuan; Guo, Weijie; Bian, Zehua; Quan, Chao; Liu, Zhihui; Wang, Yugang; Yu, Jian; Du, Xiang; Hua, Dong; Huang, Zhaohui

    2014-01-01

    The expression of miR-638 was found downregulated in colorectal carcinoma (CRC) in our previous study. However, the role of miR-638 in CRC remains unknown. The aim of this study was to determine the function and mechanism of miR-638 in CRC. Here, we verified that miR-638 was frequently downregulated in CRC tissues compared with corresponding noncancerous tissues (NCTs) in an expanded CRC cohort, and survival analysis showed that the downregulation of miR-638 in CRC was associated with poor prognoses. The ectopic expression of miR-638 inhibited CRC cell proliferation, invasion and arrest the cell cycle in G1 phase, whereas the repression of miR-638 significantly promoted CRC cell growth, invasion and cell cycle G1/S transition. Subsequent mechanism analyses revealed that miR-638 inhibited CRC cell growth, invasion and cell cycle progression by targeting TSPAN1. TSPAN1 protein levels were upregulated in CRC samples and were inversely correlated with miR-638 levels. More importantly, high TSPAN1 expression levels in CRC tissues predicted poor overall survival, and appears to be an independent prognostic factor for CRC survival. Furthermore, CpG island methylation analyses revealed that the miR-638 promoter was hypermethylated in CRC and that attenuating promoter methylation was sufficient to restore miR-638 expression in CRC cells. Taken together, our current data demonstrate that miR-638 functions as a tumor suppressor in human CRC by inhibiting TSPAN1, and that TSPAN1 is a potential prognostic factor for CRC. PMID:25301729

  7. A planarian p53 homolog regulates proliferation and self-renewal in adult stem cell lineages

    OpenAIRE

    Pearson, Bret J.; Alvarado, Alejandro Sánchez

    2010-01-01

    The functions of adult stem cells and tumor suppressor genes are known to intersect. However, when and how tumor suppressors function in the lineages produced by adult stem cells is unknown. With a large population of stem cells that can be manipulated and studied in vivo, the freshwater planarian is an ideal system with which to investigate these questions. Here, we focus on the tumor suppressor p53, homologs of which have no known role in stem cell biology in any invertebrate examined thus ...

  8. miR-29b suppresses CML cell proliferation and induces apoptosis via regulation of BCR/ABL1 protein

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yajuan; Wang, Haixia; Tao, Kun [Department of Clinical Hematology, Key Laboratory of Laboratory Medical Diagnostics Designated of Ministry of Education, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong District, Chongqing 400016 (China); Xiao, Qing [Department of Hematology, The First Affiliated Hospital, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong District, Chongqing 400016 (China); Huang, Zhenglan; Zhong, Liang; Cao, Weixi [Department of Clinical Hematology, Key Laboratory of Laboratory Medical Diagnostics Designated of Ministry of Education, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong District, Chongqing 400016 (China); Wen, Jianping [Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada L8N 3Z5 (Canada); Feng, Wenli, E-mail: fengwlcqmu@sina.com [Department of Clinical Hematology, Key Laboratory of Laboratory Medical Diagnostics Designated of Ministry of Education, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong District, Chongqing 400016 (China)

    2013-05-01

    MicroRNAs (miRNAs) are small RNAs that regulate gene expression posttranscriptionally and are critical for many cellular pathways. Recent evidence has shown that aberrant miRNA expression profiles and unique miRNA signaling pathways are present in many cancers. Here, we demonstrate that miR-29b is markedly lower expressed in CML patient samples. Bioinformatics analysis reveals a conserved target site for miR-29b in the 3′-untranslated region (UTR) of ABL1. miR-29b significantly suppresses the activity of a luciferase reporter containing ABL1-3′UTR and this activity is not observed in cells transfected with mutated ABL1-3′UTR. Enforced expression of miR-29b in K562 cells inhibits cell growth and colony formation ability thereby inducing apoptosis through cleavage of procaspase 3 and PARP. Furthermore, K562 cells transfected with a siRNA targeting ABL1 show similar growth and apoptosis phenotypes as cells overexpression of miR-29b. Collectively, our results suggest that miR-29b may function as a tumor suppressor by targeting ABL1 and BCR/ABL1. - Highlights: ► miR-29b expression was downregulated in CML patients. ► ABL1 was identified as a direct target gene of miR-29b. ► Enforced expression of miR-29b inhibits cell proliferation and induces apoptosis. ► miR-29b might be a therapeutic target to CML.

  9. Peroxisome Proliferator-Activated Receptor γ Regulates the Expression of Lipid Phosphate Phosphohydrolase 1 in Human Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Yazi Huang

    2014-01-01

    Full Text Available Lipid phosphate phosphohydrolase 1 (LPP1, a membrane ectophosphohydrolase regulating the availability of bioactive lipid phosphates, plays important roles in cellular signaling and physiological processes such as angiogenesis and endothelial migration. However, the regulated expression of LPP1 remains largely unknown. Here, we aimed to examine a role of peroxisome proliferator-activated receptor γ (PPARγ in the transcriptional control of LPP1 gene expression. In human umbilical vein endothelial cells (HUVECs, quantitative reverse transcriptase polymerase chain reaction (qRT-PCR demonstrated that activation of PPARγ increased the mRNA level of LPP1. Chromatin immunoprecipitation assay showed that PPARγ binds to the putative PPAR-responsive elements (PPREs within the 5′-flanking region of the human LPP1 gene. Genomic fragment containing 1.7-kilobase of the promoter region was cloned by using PCR. The luciferase reporter assays demonstrated that overexpression of PPARγ and rosiglitazone, a specific ligand for PPARγ, could significantly upregulate the reporter activity. However, site-directed mutagenesis of the PPRE motif abolished the induction. In conclusion, our results demonstrated that PPARγ transcriptionally activated the expression of LPP1 gene in ECs, suggesting a potential role of PPARγ in the metabolism of phospholipids.

  10. Cyclin-dependent kinase 5 acts as a critical determinant of AKT-dependent proliferation and regulates differential gene expression by the androgen receptor in prostate cancer cells.

    Science.gov (United States)

    Lindqvist, Julia; Imanishi, Susumu Y; Torvaldson, Elin; Malinen, Marjo; Remes, Mika; Örn, Fanny; Palvimo, Jorma J; Eriksson, John E

    2015-06-01

    Contrary to cell cycle-associated cyclin-dependent kinases, CDK5 is best known for its regulation of signaling processes in differentiated cells and its destructive activation in Alzheimer's disease. Recently, CDK5 has been implicated in a number of different cancers, but how it is able to stimulate cancer-related signaling pathways remains enigmatic. Our goal was to study the cancer-promoting mechanisms of CDK5 in prostate cancer. We observed that CDK5 is necessary for proliferation of several prostate cancer cell lines. Correspondingly, there was considerable growth promotion when CDK5 was overexpressed. When examining the reasons for the altered proliferation effects, we observed that CDK5 phosphorylates S308 on the androgen receptor (AR), resulting in its stabilization and differential expression of AR target genes including several growth-priming transcription factors. However, the amplified cell growth was found to be separated from AR signaling, further corroborated by CDK5-dependent proliferation of AR null cells. Instead, we found that the key growth-promoting effect was due to specific CDK5-mediated AKT activation. Down-regulation of CDK5 repressed AKT phosphorylation by altering its intracellular localization, immediately followed by prominent cell cycle inhibition. Taken together, these results suggest that CDK5 acts as a crucial signaling hub in prostate cancer cells by controlling androgen responses through AR, maintaining and accelerating cell proliferation through AKT activation, and releasing cell cycle breaks. PMID:25851605

  11. Hepatitis B virus X protein mutant HBxΔ127 promotes proliferation of hepatoma cells through up-regulating miR-215 targeting PTPRT

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Fabao [Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071 (China); Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China); You, Xiaona [Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071 (China); Chi, Xiumei [Department of Hepatology, The First Hospital, Jilin University, Changchun 130021 (China); Wang, Tao [Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071 (China); Ye, Lihong [Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China); Niu, Junqi, E-mail: junqiniu@yahoo.com.cn [Department of Hepatology, The First Hospital, Jilin University, Changchun 130021 (China); Zhang, Xiaodong, E-mail: zhangxd@nankai.edu.cn [Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071 (China)

    2014-02-07

    Highlights: • Relative to wild type HBx, HBX mutant HBxΔ127 strongly enhances cell proliferation. • Relative to wild type HBx, HBxΔ127 remarkably up-regulates miR-215 in hepatoma cells. • HBxΔ127-elevated miR-215 promotes cell proliferation via targeting PTPRT mRNA. - Abstract: The mutant of virus is a frequent event. Hepatitis B virus X protein (HBx) plays a vital role in the development of hepatocellular carcinoma (HCC). Therefore, the identification of potent mutant of HBx in hepatocarcinogenesis is significant. Previously, we identified a natural mutant of the HBx gene (termed HBxΔ127). Relative to wild type HBx, HBxΔ127 strongly enhanced cell proliferation and migration in HCC. In this study, we aim to explore the mechanism of HBxΔ127 in promotion of proliferation of hepatoma cells. Our data showed that both wild type HBx and HBxΔ127 could increase the expression of miR-215 in hepatoma HepG2 and H7402 cells. However, HBxΔ127 was able to significantly increase miR-215 expression relative to wild type HBx in the cells. We identified that protein tyrosine phosphatase, receptor type T (PTPRT) was one of the target genes of miR-215 through targeting 3′UTR of PTPRT mRNA. In function, miR-215 was able to promote the proliferation of hepatoma cells. Meanwhile anti-miR-215 could partially abolish the enhancement of cell proliferation mediated by HBxΔ127 in vitro. Knockdown of PTPRT by siRNA could distinctly suppress the decrease of cell proliferation mediated by anti-miR-215 in HepG2-XΔ127/H7402-XΔ127 cells. Moreover, we found that anti-miR-215 remarkably inhibited the tumor growth of hepatoma cells in nude mice. Collectively, relative to wild type HBx, HBxΔ127 strongly enhances proliferation of hepatoma cells through up-regulating miR-215 targeting PTPRT. Our finding provides new insights into the mechanism of HBx mutant HBxΔ127 in promotion of proliferation of hepatoma cells.

  12. Regulation of Cell Proliferation and Migration by miR-203 via GAS41/miR-10b Axis in Human Glioblastoma Cells

    Science.gov (United States)

    Pal, Dhananjaya; Mukhopadhyay, Debasmita; Ramaiah, M. Janaki; Sarma, Pranjal; Bhadra, Utpal; Bhadra, Manika Pal

    2016-01-01

    Glioma amplified sequence 41(GAS41) is a potent transcription factor that play a crucial role in cell proliferation and survival. In glioblastoma, the expression of GAS41 at both transcriptional and post transcriptional level needs to be tightly maintained in response to cellular signals. Micro RNAs (miRNA) are small non coding RNA that act as important regulators for modulating the expression of various target genes. Studies have shown that several miRNAs play role in the post-transcriptional regulation of GAS41. Here we identified GAS41 as a novel target for endogenous miR-203 and demonstrate an inverse correlation of miR-203 expression with GAS41 in glioma cell lines (HNGC2 and U87). Over expression of miR-203 negatively regulates GAS41 expression in U87 and HNGC2 cell lines. Moreover, miR-203 restrained miR-10b action by suppressing GAS41. GAS41 is essential for repressing p53 in tumor suppressor pathway during cell proliferation. Enforced expression of GAS41 produced contradictory effect on miR-203 but was able to enhance p53 tumor suppressor pathway associated protein. It was also found that miR-203 maintains the stability of p53 as knock down of p53 expression using siRNA resulted in down regulation of pri-miR and mature miR-203 expression. Conversely reconstitution of miR-203 expression induced apoptosis and inhibited migratory property of glioma cells. Taken together, we show that miR-203 is a key negative regulator of GAS41 and acts as tumor suppressor microRNA in glioma. PMID:27467502

  13. A Sox Transcription Factor Is a Critical Regulator of Adult Stem Cell Proliferation in the Drosophila Intestine

    OpenAIRE

    Fanju W. Meng; Benoît Biteau

    2015-01-01

    Adult organs and their resident stem cells are constantly facing the challenge of adapting cell proliferation to tissue demand, particularly in response to environmental stresses. Whereas most stress-signaling pathways are conserved between progenitors and differentiated cells, stem cells have the specific ability to respond by increasing their proliferative rate, using largely unknown mechanisms. Here, we show that a member of the Sox family of transcription factors in Drosophila, Sox21a, is...

  14. Regulation of proliferation and gene expression in cultured human aortic smooth muscle cells by resveratrol and standardized grape extracts

    International Nuclear Information System (INIS)

    Epidemiologic studies suggest that low to moderate consumption of red wine is inversely associated with the risk of coronary heart disease; the protection is in part attributed to grape-derived polyphenols, notably trans-resveratrol, present in red wine. It is not clear whether the cardioprotective effects of resveratrol can be reproduced by standardized grape extracts (SGE). In the present studies, we determined, using cultured human aortic smooth muscle cells (HASMC), growth and specific gene responses to resveratrol and SGE provided by the California Table Grape Commission. Suppression of HASMC proliferation by resveratrol was accompanied by a dose-dependent increase in the expression of tumor suppressor gene p53 and heat shock protein HSP27. Using resveratrol affinity chromatography and biochemical fractionation procedures, we showed by immunoblot analysis that treatment of HASMC with resveratrol increased the expression of quinone reductase I and II, and also altered their subcellular distribution. Growth of HASMC was significantly inhibited by 70% ethanolic SGE; however, gene expression patterns in various cellular compartments elicited in response to SGE were substantially different from those observed in resveratrol-treated cells. Further, SGE also differed from resveratrol in not being able to induce relaxation of rat carotid arterial rings. These results indicate that distinct mechanisms are involved in the regulation of HASMC growth and gene expression by SGE and resveratrol

  15. M2 pyruvate kinase provides a mechanism for nutrient sensing and regulation of cell proliferation

    OpenAIRE

    Morgan, Hugh P.; O???Reilly, Francis J.; Wear, Martin A.; O'Neill, Robert; Fothergill-Gilmore, Linda A.; Hupp, Ted; Walkinshaw, Malcolm D.

    2013-01-01

    We show that the M2 isoform of pyruvate kinase (M2PYK) exists in equilibrium between monomers and tetramers regulated by allosteric binding of naturally occurring small-molecule metabolites. Phenylalanine stabilizes an inactive T-state tetrameric conformer and inhibits M2PYK with an IC50 value of 0.24 mM, whereas thyroid hormone (triiodo-l-thyronine, T3) stabilizes an inactive monomeric form of M2PYK with an IC50 of 78 nM. The allosteric activator fructose-1,6-bisphosphate [F16BP, AC50 (conce...

  16. Regulation of Schwann cell proliferation in cultured segments of the adult rat sciatic nerve

    DEFF Research Database (Denmark)

    Svenningsen, Åsa Fex; Kanje, M

    1998-01-01

    of Schwann cells. Removal of extracellular Ca2+ by addition of EGTA to the culture medium suppressed [3H] thymidine incorporation as did the calmodulin inhibitor 48/80. The Ca2+ ionophore A23187 increased incorporation. Staurosporin, an inhibitor of protein kinase C (PKC), suppressed [3H] thymidine...

  17. Regulation of Prostate Development and Benign Prostatic Hyperplasia by Autocrine Cholinergic Signaling via Maintaining the Epithelial Progenitor Cells in Proliferating Status

    Directory of Open Access Journals (Sweden)

    Naitao Wang

    2016-05-01

    Full Text Available Regulation of prostate epithelial progenitor cells is important in prostate development and prostate diseases. Our previous study demonstrated a function of autocrine cholinergic signaling (ACS in promoting prostate cancer growth and castration resistance. However, whether or not such ACS also plays a role in prostate development is unknown. Here, we report that ACS promoted the proliferation and inhibited the differentiation of prostate epithelial progenitor cells in organotypic cultures. These results were confirmed by ex vivo lineage tracing assays and in vivo renal capsule recombination assays. Moreover, we found that M3 cholinergic receptor (CHRM3 was upregulated in a large subset of benign prostatic hyperplasia (BPH tissues compared with normal tissues. Activation of CHRM3 also promoted the proliferation of BPH cells. Together, our findings identify a role of ACS in maintaining prostate epithelial progenitor cells in the proliferating state, and blockade of ACS may have clinical implications for the management of BPH.

  18. The regulation of tooth morphogenesis is associated with epithelial cell proliferation and the expression of Sonic hedgehog through epithelial-mesenchymal interactions

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Kentaro; Murofushi, Mayumi [Faculty of Industrial Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Nakao, Kazuhisa; Morita, Ritsuko [Research Institute for Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Ogawa, Miho [Research Institute for Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Organ Technologies Inc., Tokyo 101-0048 (Japan); Tsuji, Takashi, E-mail: t-tsuji@rs.noda.tus.ac.jp [Faculty of Industrial Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Research Institute for Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Organ Technologies Inc., Tokyo 101-0048 (Japan)

    2011-02-18

    Research highlights: {yields} Bioengineered teeth regulated the contact area of epithelium and mesenchyme. {yields} The crown width is regulated by the contact area of the epithelium and mesenchyme. {yields} This regulation is associated with cell proliferation and Sonic hedgehog expression. {yields} The cusp number is correlated with the crown width of the bioengineered tooth. {yields} Cell proliferation and Shh expression areas regulate the tooth morphogenesis. -- Abstract: Ectodermal organs, such as the tooth, salivary gland, hair, and mammary gland, develop through reciprocal epithelial-mesenchymal interactions. Tooth morphologies are defined by the crown width and tooth length (macro-morphologies), and by the number and locations of the cusp and roots (micro-morphologies). In our current study, we report that the crown width of a bioengineered molar tooth, which was reconstructed using dissociated epithelial and mesenchymal cells via an organ germ method, can be regulated by the contact area between epithelial and mesenchymal cell layers. We further show that this is associated with cell proliferation and Sonic hedgehog (Shh) expression in the inner enamel epithelium after the germ stage has formed a secondary enamel knot. We also demonstrate that the cusp number is significantly correlated with the crown width of the bioengineered tooth. These findings suggest that the tooth micro-morphology, i.e. the cusp formation, is regulated after the tooth width, or macro-morphology, is determined. These findings also suggest that the spatiotemporal patterning of cell proliferation and the Shh expression areas in the epithelium regulate the crown width and cusp formation of the developing tooth.

  19. De-regulated microRNAs in pediatric cancer stem cells target pathways involved in cell proliferation, cell cycle and development.

    Directory of Open Access Journals (Sweden)

    Patricia C Sanchez-Diaz

    Full Text Available BACKGROUND: microRNAs (miRNAs have been implicated in the control of many biological processes and their deregulation has been associated with many cancers. In recent years, the cancer stem cell (CSC concept has been applied to many cancers including pediatric. We hypothesized that a common signature of deregulated miRNAs in the CSCs fraction may explain the disrupted signaling pathways in CSCs. METHODOLOGY/RESULTS: Using a high throughput qPCR approach we identified 26 CSC associated differentially expressed miRNAs (DEmiRs. Using BCmicrO algorithm 865 potential CSC associated DEmiR targets were obtained. These potential targets were subjected to KEGG, Biocarta and Gene Ontology pathway and biological processes analysis. Four annotated pathways were enriched: cell cycle, cell proliferation, p53 and TGF-beta/BMP. Knocking down hsa-miR-21-5p, hsa-miR-181c-5p and hsa-miR-135b-5p using antisense oligonucleotides and small interfering RNA in cell lines led to the depletion of the CSC fraction and impairment of sphere formation (CSC surrogate assays. CONCLUSION: Our findings indicated that CSC associated DEmiRs and the putative pathways they regulate may have potential therapeutic applications in pediatric cancers.

  20. The surface nanostructures of titanium alloy regulate the proliferation of endothelial cells

    Directory of Open Access Journals (Sweden)

    Min Lai

    2014-02-01

    Full Text Available To investigate the effect of surface nanostructures on the behaviors of human umbilical vein endothelial cells (HUVECs, surface nanostructured titanium alloy (Ti-3Zr2Sn-3Mo-25Nb, TLM was fabricated by surface mechanical attrition treatment (SMAT technique. Field emission scanning electron microscopy (FE-SEM, atomic force microscopy (AFM, transmission electron microscopy (TEM and X-ray diffraction (XRD were employed to characterize the surface nanostructures of the TLM, respectively. The results demonstrated that nano-crystalline structures with several tens of nanometers were formed on the surface of TLM substrates. The HUVECs grown onto the surface nanostructured TLM spread well and expressed more vinculin around the edges of cells. More importantly, HUVECs grown onto the surface nanostructured TLM displayed significantly higher (p < 0.01 or p < 0.05 cell adhesion and viabilities than those of native titanium alloy. HUVECs cultured on the surface nanostructured titanium alloy displayed significantly higher (p < 0.01 or p < 0.05 productions of nitric oxide (NO and prostacyclin (PGI2 than those of native titanium alloy, respectively. This study provides an alternative for the development of titanium alloy based vascular stents.

  1. BKCa and hEag1 channels regulate cell proliferation and differentiation in human bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Zhang, Ying-Ying; Yue, Jianbo; Che, Hui; Sun, Hai-Ying; Tse, Hung-Fat; Li, Gui-Rong

    2014-02-01

    Human bone marrow-derived mesenchymal stem cells (MSCs) serve as a reservoir for the continuous renewal of various mesenchymal tissues; however, cellular physiology of ion channels is not fully understood. The present study investigated potential roles of large-conductance Ca(2+) -activated potassium (BKCa ) channels and ether-à-go-go potassium (hEag1 or Kv10.1) channels in regulating cell proliferation and differentiation in human MSCs. We found that inhibition of BKCa with paxilline or hEag1 with astemizole, or knockdown of BKCa with shRNAs targeting KCa1.1 or hEag1 channels with shRNAs targeting KCNH1 arrested the cells at G0/G1 phase. In addition, silencing BKCa or hEag1 channels significantly reduced adipogenic differentiation with decrease of lipid accumulation and expression of the adipocyte marker PPARγ, and decreased osteogenic differentiation with reduction of mineral precipitation and osteocalcin. These effects were accompanied with a reduced cyclin D1, cyclin E, p-ERK1/2, and p-Akt. Our results demonstrate that BKCa and hEag1 channels not only regulate cell proliferation, but also participate in the adipogenic and osteogenic differentiations in human MSCs, which indicates that BKCa and hEag1 channels may be essential in maintaining bone marrow physiological function and bone regeneration. PMID:23881642

  2. PAK1IP1, a ribosomal stress-induced nucleolar protein, regulates cell proliferation via the p53–MDM2 loop

    Science.gov (United States)

    Yu, Weishi; Qiu, Zhongwei; Gao, Na; Wang, Liren; Cui, Hengxiang; Qian, Yu; Jiang, Li; Luo, Jian; Yi, Zhengfang; Lu, Hua; Li, Dali; Liu, Mingyao

    2011-01-01

    Cell growth and proliferation are tightly controlled via the regulation of the p53–MDM2 feedback loop in response to various cellular stresses. In this study, we identified a nucleolar protein called PAK1IP1 as another regulator of this loop. PAK1IP1 was induced when cells were treated with chemicals that disturb ribosome biogenesis. Overexpression of PAK1IP1 inhibited cell proliferation by inducing p53-dependent G1 cell-cycle arrest. PAK1IP1 bound to MDM2 and inhibited its ability to ubiquitinate and to degrade p53, consequently leading to the accumulation of p53 levels. Interestingly, knockdown of PAK1IP1 in cells also inhibited cell proliferation and induced p53-dependent G1 arrest. Deficiency of PAK1IP1 increased free ribosomal protein L5 and L11 which were required for PAK1IP1 depletion-induced p53 activation. Taken together, our results reveal that PAK1IP1 is a new nucleolar protein that is crucial for rRNA processing and plays a regulatory role in cell proliferation via the p53–MDM2 loop. PMID:21097889

  3. Up-regulation of TIMP-2 expression promotes SHI-1 leukemic cells proliferation and infiltration in immunodeficiency mice

    Institute of Scientific and Technical Information of China (English)

    Li Zhenjiang; Chen Zixing; Cen Jiannong; He Jun; Qiu Qiaocheng; Xue Yongquan

    2014-01-01

    Background MMPs and TIMPs play important roles in tumor angiogenesis and invasion.Studies have shown that TIMP-2 has two roles in tumor invasion.However,its role in leukemic infiltration has not been well investigated.This study explored the roles of TIMP-2 in extramedullary infiltration of acute monocytic leukemic SHI-1 cells both in vitro and in vitro.Methods A retroviral vector carrying the human TIMP-2 cDNA was constructed and transfected into the monocytic leukemic cell line SHI-1.The expression of TIMP-2 in the positive clones was determined.The proliferation of SHI-1 cells was examined by MTT assay.Trans-Matrigel invasion assays were used to investigate the infiltration ability in vitro.SHI-1 cells were intravenously injected into pre-treated nu/nu mice to investigate the infiltration ability feature in vitro.Results The expression of TIMP-2 on the cell membrane was significantly elevated in SHI-1/TIMP-2 cells.Over-expression of TIMP-2 promoted the cells proliferation and the invasions in vitro.The SHI-1/TIMP-2 cells demonstrated higher infiltration ability when intravenously injected into nu/nu mice.Conclusion Over-expression of TIMP-2,especially on the cell membrane,may play important roles in promoting the proliferation and infiltration of SHI-1 leukemic cells.

  4. BAFF induces spleen CD4+ T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression

    International Nuclear Information System (INIS)

    Highlights: ► Firstly analyze the mechanism of BAFF and anti-CD3 co-stimulation on purified mouse splenic CD4+ T cells. ► Carrying out siRNA technology to study FOXO3A protein function. ► Helpful to understand the T cell especially CD4+ T cell‘s role in immunological reaction. -- Abstract: The TNF ligand family member “B cell-activating factor belonging to the TNF family” (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4+ spleen T cell proliferation when co-stimulated with anti-CD3. Expression of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4+ T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4+ spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4+ T cell proliferation.

  5. Global characteristics of CSIG-associated gene expression changes in human HEK293 cells and the implications for CSIG regulating cell proliferation and senescence

    Directory of Open Access Journals (Sweden)

    Liwei eMa

    2015-05-01

    Full Text Available Cellular senescence-inhibited gene (CSIG, also named ribosomal_L1 domain-containing 1 (RSL1D1, is implicated in various processes including cell cycle regulation, cellular senescence, apoptosis, and tumor metastasis. However, little is known about the regulatory mechanism underlying its functions. To screen important targets and signaling pathways modulated by CSIG, we compared the gene expression profiles in CSIG-silencing and control HEK293 cells using Affymetrix microarray Human Genome U133 Plus 2.0 GeneChips. A total of 590 genes displayed statistically significant expression changes, with 279 genes up-regulated and 311 down-regulated, respectively. These genes are involved in a broad array of biological processes, mainly in transcriptional regulation, cell cycle, signal transduction, oxidation reduction, development, and cell adhesion. The differential expression of genes such as ZNF616, KPNA5, MAP3K3 were further validated by real-time PCR and western blot analysis. Furthermore, we investigated the correlated expression patterns of ESCO1, KPNA5, MAP3K3 and CSIG during cell cycle and senescence progression, which imply the important pathways CSIG regulating cell cycle and senescence. The mechanism study showed that CSIG modulated the mRNA half-life of Cdc14B, CASP7 and CREBL2. This study shows that expression profiling can be used to identify genes that are transcriptionally or post-transcriptionally modified following CSIG knockdown and to reveal the molecular mechanism of cell proliferation and senescence regulated by CSIG.

  6. MEK1 and MEK2 differentially regulate human insulin-and insulin glargine-induced human bladder cancer T24 cell proliferation

    Institute of Scientific and Technical Information of China (English)

    LIU Shan-ying; LIANG Ying; LIN Tian-xin; SU Fang; LIANG Wei-wen; Uwe Heemann; LI Yan

    2012-01-01

    Background Increased risk of bladder cancer has been reported in diabetic patients.This study was to investigate the roles of mitogen-activated protein kinase kinase (MEK) 1 and 2 in the regulation of human insulin-and insulin glargine-induced proliferation of human bladder cancer T24 cells.Methods In the absence or presence of a selective inhibitor for MEK1 (PD98059) or a specific siRNA for MEK2 (siMEK2),with or without addition of insulin or glargine,T24 cell proliferation was evaluated by cell counting kit (CCK)-8 assay.Protein expression of MEK2,phosphorylation of ERK1/2 and Akt was analyzed by Western blotting.Results T24 cell proliferation was promoted by PD98059 at 5-20 μmol/L,inhibited by siMEK2 at 25-100 nmol/L.PD98059 and siMEK2 remarkably reduced phosphorylated ERK1/2.Insulin-and glargine-induced T24 cell proliferation was enhanced by PD98059,suppressed while not blocked by siMEK2.Insulin-and glargine-induced ERK1/2 activation was blocked by PD98059 or siMEK2 treatment,whereas activation of Akt was not affected.Conclusion MEK1 inhibits while MEK2 contributes to normal and human insulin-and insulin glargine-induced human bladder cancer T24 cell proliferation.

  7. RNA-seq Analysis of δ9-Tetrahydrocannabinol-treated T Cells Reveals Altered Gene Expression Profiles That Regulate Immune Response and Cell Proliferation.

    Science.gov (United States)

    Yang, Xiaoming; Bam, Marpe; Nagarkatti, Prakash S; Nagarkatti, Mitzi

    2016-07-22

    Marijuana has drawn significant public attention and concern both for its medicinal and recreational use. Δ9-Tetrahydrocannabinol (THC), which is the main bioactive component in marijuana, has also been shown to possess potent anti-inflammatory properties by virtue of its ability to activate cannabinoid receptor-2 (CB-2) expressed on immune cells. In this study, we used RNA-seq to quantify the transcriptomes and transcript variants that are differentially regulated by THC in super antigen-activated lymph node cells and CD4(+) T cells. We found that the expressions of many transcripts were altered by THC in both total lymph node cells and CD4(+) T cells. Furthermore, the abundance of many miRNA precursors and long non-coding RNAs was dramatically altered in THC-treated mice. For example, the expression of miR-17/92 cluster and miR-374b/421 cluster was down-regulated by THC. On the other hand miR-146a, which has been shown to induce apoptosis, was up-regulated by THC. Long non-coding RNAs that are expressed from the opposite strand of CD27 and Appbp2 were induced by THC. In addition, THC treatment also caused alternative promoter usage and splicing. The functions of those altered transcripts were mainly related to immune response and cell proliferation. PMID:27268054

  8. Opposing roles of PKA and EPAC in the cAMP-dependent regulation of schwann cell proliferation and differentiation [corrected].

    Directory of Open Access Journals (Sweden)

    Ketty Bacallao

    Full Text Available In Schwann cells (SCs, cyclic adenosine monophosphate (cAMP not only induces differentiation into a myelinating SC-related phenotype, but also synergistically enhances the mitogenic action of growth factors such as neuregulin. To better understand the molecular mechanism by which cAMP exerts these apparently contradictory functions, we investigated the role of the two main effectors of cAMP, protein kinase A (PKA and the exchange protein activated by cAMP (EPAC, on the proliferation and differentiation of both isolated and axon-related SCs. For these studies, a variety of PKA and EPAC agonists and antagonists were used, including pathway-selective analogs of cAMP and pharmacological inhibitors. Our studies indicated that the activity of PKA rather than EPAC was required for the adjuvant effect of cAMP on S-phase entry, whereas the activity of EPAC rather than PKA was required for SC differentiation and myelin formation. Even though selective EPAC activation had an overall anti-proliferative effect in SCs, it failed to drive the expression of Krox-20, a master regulator of myelination, and that of myelin-specific proteins and lipids, suggesting that EPAC activation was insufficient to drive a full differentiating response. Interestingly, inhibition of EPAC activity resulted in a drastic impairment of SC differentiation and myelin formation but not Krox-20 expression, which indicates an independent mechanism of Krox-20 regulation in response to cAMP. In conclusion, our data supports the idea that the outcome of cAMP signaling in SCs depends on the particular set of effectors activated. Whereas the mitogenic action of cAMP relies exclusively on PKA activity, the differentiating action of cAMP requires a PKA-independent (non-canonical cAMP-specific pathway that is partially transduced by EPAC.

  9. Opposing roles of PKA and EPAC in the cAMP-dependent regulation of schwann cell proliferation and differentiation [corrected].

    Science.gov (United States)

    Bacallao, Ketty; Monje, Paula V

    2013-01-01

    In Schwann cells (SCs), cyclic adenosine monophosphate (cAMP) not only induces differentiation into a myelinating SC-related phenotype, but also synergistically enhances the mitogenic action of growth factors such as neuregulin. To better understand the molecular mechanism by which cAMP exerts these apparently contradictory functions, we investigated the role of the two main effectors of cAMP, protein kinase A (PKA) and the exchange protein activated by cAMP (EPAC), on the proliferation and differentiation of both isolated and axon-related SCs. For these studies, a variety of PKA and EPAC agonists and antagonists were used, including pathway-selective analogs of cAMP and pharmacological inhibitors. Our studies indicated that the activity of PKA rather than EPAC was required for the adjuvant effect of cAMP on S-phase entry, whereas the activity of EPAC rather than PKA was required for SC differentiation and myelin formation. Even though selective EPAC activation had an overall anti-proliferative effect in SCs, it failed to drive the expression of Krox-20, a master regulator of myelination, and that of myelin-specific proteins and lipids, suggesting that EPAC activation was insufficient to drive a full differentiating response. Interestingly, inhibition of EPAC activity resulted in a drastic impairment of SC differentiation and myelin formation but not Krox-20 expression, which indicates an independent mechanism of Krox-20 regulation in response to cAMP. In conclusion, our data supports the idea that the outcome of cAMP signaling in SCs depends on the particular set of effectors activated. Whereas the mitogenic action of cAMP relies exclusively on PKA activity, the differentiating action of cAMP requires a PKA-independent (non-canonical) cAMP-specific pathway that is partially transduced by EPAC.

  10. Anti-inflammatory drugs suppress proliferation and induce apoptosis through altering expressions of cell cycle regulators and pro-apoptotic factors in cultured human osteoblasts

    International Nuclear Information System (INIS)

    It has been reported that anti-inflammatory drugs (AIDs) inhibited bone repair in animal studies, and suppressed proliferation and induced cell death in rat osteoblast cultures. In this study, we further investigated the molecular mechanisms of AID effects on proliferation and cell death in human osteoblasts (hOBs). We examined the effects of dexamethasone (10-7 and 10-6 M), non-selective non-steroidal anti-inflammatory drugs (NSAIDs): indomethacin, ketorolac, piroxicam and diclofenac (10-5 and 10-4 M), and COX-2 inhibitor: celecoxib (10-6 and 10-5 M) on proliferation, cytotoxicity, cell death, and mRNA and protein levels of cell cycle and apoptosis-related regulators in hOBs. All the tested AIDs significantly inhibited proliferation and arrested cell cycle at G0/G1 phase in hOBs. Celecoxib and dexamethasone, but not non-selective NSAIDs, were found to have cytotoxic effects on hOB, and further demonstrated to induce apoptosis and necrosis (at higher concentration) in hOBs. We further found that indomethacin, celecoxib and dexamethasone increased the mRNA and protein expressions of p27kip1 and decreased those of cyclin D2 and p-cdk2 in hOBs. Bak expression was increased by celecoxib and dexamethasone, while Bcl-XL level was declined only by dexamethasone. Furthermore, the replenishment of PGE1, PGE2 or PGF2α did not reverse the effects of AIDs on proliferation and expressions of p27kip1 and cyclin D2 in hOBs. We conclude that the changes in expressions of regulators of cell cycle (p27kip1 and cyclin D2) and/or apoptosis (Bak and Bcl-XL) by AIDs may contribute to AIDs caused proliferation suppression and apoptosis in hOBs. This effect might not relate to the blockage of prostaglandin synthesis by AIDs

  11. Down-regulation of Thanatos-associated protein 11 by BCR-ABL promotes CML cell proliferation through c-Myc expression.

    Science.gov (United States)

    Nakamura, Satoki; Yokota, Daisuke; Tan, Lin; Nagata, Yasuyuki; Takemura, Tomonari; Hirano, Isao; Shigeno, Kazuyuki; Shibata, Kiyoshi; Fujisawa, Shinya; Ohnishi, Kazunori

    2012-03-01

    Bcr-Abl activates various signaling pathways in chronic myelogenous leukemia (CML) cells. The proliferation of Bcr-Abl transformed cells is promoted by c-Myc through the activation of Akt, JAK2 and NF-κB. However, the mechanism by which c-Myc regulates CML cell proliferation is unclear. In our study, we investigated the role of Thanatos-associated protein 11 (THAP11), which inhibits c-Myc transcription, in CML cell lines and in hematopoietic progenitor cells derived from CML patients. The induction of THAP11 expression by Abl kinase inhibitors in CML cell lines and in CML-derived hematopoietic progenitor cells resulted in the suppression of c-Myc. In addition, over-expression of THAP11 inhibited CML cell proliferation. In colony forming cells derived from CML-aldehyde dehydrogenase (ALDH)(hi) /CD34(+) cells, treatment with Abl kinase inhibitors and siRNA depletion of Bcr-Abl induced THAP11 expression and reduced c-Myc expression, resulting in inhibited colony formation. Moreover, overexpression of THAP11 significantly decreased the colony numbers, and also inhibited the expression of c-myc target genes such as Cyclin D1, ODC and induced the expression of p21(Cip1) . The depletion of THAP11 inhibited JAK2 or STAT5 inactivation-mediated c-Myc reduction in ALDH(hi) /CD34(+) CML cells. Thus, the induced THAP11 might be one of transcriptional regulators of c-Myc expression in CML cell. Therefore, the induction of THAP11 has a potential possibility as a target for the inhibition of CML cell proliferation. PMID:21400515

  12. Id2 regulates the proliferation of squamous cell carcinoma in vitro via the NF-κB/Cyclin D1 pathway

    Institute of Scientific and Technical Information of China (English)

    Chuan Wang; Qiang Chen; Yuki Hamajima; Wei Sun; Yi-Qing Zheng; Xiao-Hua Hu; Frank G.Ondrey; Ji-Zhen Lin

    2012-01-01

    Squamous cell carcinoma (SCC) is a significant cause of cancer morbidity and mortality worldwide,with an incidence of up to 166 cases per 100 000 population.It arises in the skin,upper aerodigestive tract,lung,and cervix and affects more than 200 000 Americans each year.We report here that a microarray experiment comparing 41 SCC and 13 normal tissue specimens showed that Id2,a gene that controls the cell cycle,was significantly up-regulated in SCC.Enforced expression of Id2 in vitro stimulated the proliferation of SCC cells and up-regulated the transcription of nuclear factor kappa B (NF-κB) and cyclin D1.Enhancement of the NF-κB activity with p65 significantly increased the cell proliferation and the transcription of cyclin D1,whereas inhibition of the NF-κB activity with I kappa B alpha mutant (IκBα M) and pyrroline dithiocarbamate (PDTC) abrogated cell proliferation and transcription of cyclin D1.Furthermore,a mutated NF-κB binding site in the cyclin D1 promoter fully abrogated the Id2- induced transcription of cyclin D1.Taken together,these data indicate that Id2 induces SCC tumor growth and proliferation through the NF-κB/cyclin D1 pathway.

  13. miR-107 and miR-25 simultaneously target LATS2 and regulate proliferation and invasion of gastric adenocarcinoma (GAC) cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Mingjun; Wang, Xiaolei [Cancer Center, The Second Affiliated Hospital of Anhui Medical University, Hefei 230601 (China); Li, Wanhu [MRI Room of Shandong Cancer Hospital & Institute, Jinan 250117 (China); Cui, Yongchun, E-mail: yongchuncui1@126.com [Drug Clinical Trial Institution of Shandong Cancer Hospital & Institute, #440, Jiyan Road, Jinan 250117 (China)

    2015-05-08

    Although a series of oncogenes and tumor suppressors were identified in the pathological development of gastric adenocarcinoma (GAC), the underlying molecule mechanism were still not fully understood. The current study explored the expression profile of miR-107 and miR-25 in GAC patients and their downstream regulative network. qRT-PCR analysis was performed to quantify the expression of these two miRNAs in serum samples from both patients and healthy controls. Dual luciferase assay was conducted to verify their putative bindings with LATS2. MTT assay, cell cycle assay and transwell assay were performed to explore how miR-107 and miR-25 regulate proliferation and invasion of gastric cancer cells. Findings of this study demonstrated that total miR-107 or miR-25 expression might be overexpressed in gastric cancer patients and they can simultaneously and synchronically regulate LATS2 expression, thereby affecting gastric cancer cell growth and invasion. Therefore, the miR-25/miR-107-LATS2 axis might play an important role in proliferation and invasion of the gastric cancer cells. - Highlights: • Total miR-107 and miR-25 expression is significantly increased in GAC patients. • Both miR-107 and miR-25 can promote proliferation and invasion of GAC cells. • Both miR-107 and miR-25 can target LATS2 and regulate its expression. • miR-107 and miR-25 regulate proliferation and invasion of GAC cells though LATS2.

  14. Synthetic Steroid Hormones Regulated Cell Proliferation Through MicroRNA-34a-5p in Human Ovarian Endometrioma.

    Science.gov (United States)

    Hsu, Chia-Yi; Hsieh, Tsung-Hua; Tsai, Cheng-Fang; Chen, Hung-Sheng; Liang, Peir-In; Hsu, Ya-Ling; Tsai, Eing-Mei

    2016-03-01

    Endometriosis is the hormone-dependent product of endometrial tissue found outside the uterus. Recently, micro-RNAs (miRNAs) were shown to play a role in endometriotic lesion development. However, the mechanism of steroid hormones responsible for miRNA remains obscure. In the present study, we assayed for the effects of synthetic steroid hormones (danazol, progesterone, and medroxyprogesterone acetate [MPA]) on miRNAs in endometriosis. We used a global miRNA expression profile microarray to evaluate miRNA expression in endometrial mesenchymal stem cells (EN-MSCs) of ovarian endometrioma following treatment with 1 μM danazol, progesterone, or MPA. Furthermore, we selected candidate miRNAs whose expression changed more than fivefold and compared the effects of danazol, progesterone, and MPA treatments and also compared those results with controls in EN-MSCs. Among those with a fivefold change, we found 13 ectopically upregulated miRNAs in EN-MSCs. To understand the function of these 13 miRNAs, we subjected their sequences to Ingenuity Pathway Analysis. According to both the etiology and pathogenesis of endometriosis, we found that miR-199a-5p and miR-34a-5p showed specific association with the disease, including molecular and cellular functions. Steroid hormone treatment elevated the levels of miR-199a-5p and miR-34a-5p. An inhibitor of miR-34a-5p also reduced the synthetic steroid hormones effects on cell proliferation. In vivo data revealed that miRNA levels in endometriotic lesions correlated with findings following in vitro synthetic hormone treatment. Our data show the effects of synthetic steroid hormones on miRNA regulation. These findings contribute to our understanding of the molecular impact of the synthetic steroid hormones and suggest a potential mechanism for endometriosis treatment. PMID:26819477

  15. Regulation of the Proliferation of Colon Cancer Cells by Compounds that Affect Glycolysis, Including 3-Bromopyruvate, 2-Deoxyglucose and Biguanides

    OpenAIRE

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

    2013-01-01

    In previous studies we observed that 2-deoxyglucose blocked the acidification of the medium used for culture of colon cancer cells caused by incubation with biguanides and had an additive inhibitory effect on growth. In the present work, we found that 3-bromopyruvate can also prevent the lowering of pH caused by biguanide treatment. 3-Bromopyruvate inhibited colonic cancer cell proliferation but the effect was not always additive to that of biguanides and an additive effect was more notable i...

  16. No influence of OPG and its ligands, RANKL and TRAIL, on proliferation and regulation of the calcification process in primary human vascular smooth muscle cells

    DEFF Research Database (Denmark)

    Olesen, Malene; Skov, Vibe; Mechta, Mie;

    2012-01-01

    The aim of this study was to examine the effects of the OPG-RANKL-TRAIL system on proliferation, regulation of calcification-associated genes and calcification of human vascular smooth muscle cells (HVSMCs). Small interfering (si)RNA-mediated knockdown of OPG was followed by treatment of HVSMCs...... with recombinant RANKL or TRAIL. Regulation of a calcification-associated gene set was assayed by pathway analysis of microarray results. The lack of OPG in HVSMCs or treatment with RANKL or TRAIL did not affect proliferation of HVSMCs. In addition, OPG, RANKL or TRAIL did not modify the regulation...... of a calcification-associated gene set. Finally, in the long term calcification assay, we found that cells isolated from seven different human donors showed a great variability in the response to RANKL and insulin. However, overall RANKL and/or insulin did not affect the development of calcification of HVSMCs...

  17. Mechanism by which nuclear factor-kappa beta (NF-kB) regulates ovine fetal pulmonary vascular smooth muscle cell proliferation.

    Science.gov (United States)

    Ogbozor, Uchenna D; Opene, Michael; Renteria, Lissette S; McBride, Shaemion; Ibe, Basil O

    2015-09-01

    Platelet activating factor (PAF) modulates ovine fetal pulmonary hemodynamic. PAF acts through its receptors (PAFR) in pulmonary vascular smooth muscle cells (PVSMC) to phosphorylate and induce nuclear translocation of NF-kB p65 leading to PVSMC proliferation. However, the interaction of NF-kB p65 and PAF in the nuclear domain to effect PVSMC cell growth is not clearly defined. We used siRNA-dependent translation initiation arrest to study a mechanism by which NF-kB p65 regulates PAF stimulation of PVSMC proliferation. Our hypotheses are: (a) PAF induces NF-kB p65 DNA binding and (b) NF-kB p65 siRNA attenuates PAF stimulation of PVSMC proliferation. For DNA binding, cells were fed 10 nM PAF with and without PAFR antagonists WEB 2170, CV 3988 or BN 52021 and incubated for 12 h. DNA binding was measured by specific ELISA. For NF-kB p65 siRNA effect, starved cells transfected with the siRNA were incubated for 24 h with and without 10 nM PAF. Cell proliferation was measured by DNA synthesis while expression of NF-kB p65 and PAFR protein was measured by Western blotting. In both studies, the effect of 10% FBS alone was used as the positive control. In general, PAF stimulated DNA binding which was inhibited by PAFR antagonists. siRNAs to NF-kB p65 and PAFR significantly attenuated cell proliferation compared to 10% FBS and PAF effect. Inclusion of PAF in siRNA-treated cells did not reverse inhibitory effect of NF-kB p65 siRNA on DNA synthesis. PAFR expression was inhibited in siRNA-treated cells. These data show that PAF-stimulation of PVSMC proliferation occurs via a PAFR-NF-kB p65 linked pathway.

  18. Regulation of skeletal muscle cell plasticity by the peroxisome proliferator-activated receptor gamma coactivator 1alpha

    OpenAIRE

    Handschin, C.

    2010-01-01

    Exercise triggers a pleiotropic response in skeletal muscle, which results in a profound remodeling of this tissue. Physical activity-dependent muscle fiber plasticity is regulated by a number of distinct signaling pathways. Even though most of these pathways are activated by different stimuli and in a temporally and spatially separated manner during exercise, many of the major signal transduction events converge on the peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-...

  19. Tumor suppressor BLU inhibits proliferation of nasopharyngeal carcinoma cells by regulation of cell cycle, c-Jun N-terminal kinase and the cyclin D1 promoter

    Directory of Open Access Journals (Sweden)

    Zhang Xiangning

    2012-06-01

    Full Text Available Abstract Background Tumor suppressor genes function to regulate and block tumor cell proliferation. To explore the mechanisms underlying the tumor suppression of BLU/ZMYND10 gene on a frequently lost human chromosomal region, an adenoviral vector with BLU cDNA insert was constructed. Methods BLU was re-expressed in nasopharyngeal carcinoma cells by transfection or viral infection. Clonogenic growth was assayed; cell cycle was analyzed by flow cytometry-based DNA content detection; c-Jun N-terminal kinase (JNK and cyclin D1 promoter activities were measured by reporter gene assay, and phosphorylation was measured by immunoblotting. The data for each pair of groups were compared with Student t tests. Results BLU inhibits clonogenic growth of nasopharyngeal carcinoma cells, arrests cell cycle at G1 phase, downregulates JNK and cyclin D1 promoter activities, and inhibits phosphorylation of c-Jun. Conclusions BLU inhibits growth of nasopharyngeal carcinoma cells by regulation of the JNK-cyclin D1 axis to exert tumor suppression.

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

    Science.gov (United States)

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

    2013-02-01

    In previous studies performed by our group, we observed that 2-deoxyglucose blocked the acidification of the medium used for culture of colon cancer cells caused by incubation with biguanides and it had an additive inhibitory effect on growth. In the present work, we found that 3-bromopyruvate can also prevent the lowering of pH caused by biguanide treatment. 3-Bromopyruvate inhibited colonic cancer cell proliferation, but the effect was not always additive to that of biguanides and an additive effect was more notable in combined treatment with 3-bromopyruvate and 2-deoxyglucose. The induction of alkaline phosphatase activity by butyrate was not consistently affected by combination with other agents that modified glucose metabolism. The drug combinations that were examined inhibited proliferation of wild-type and p53-null cells and affected colonic cancer lines with different growth rates. PMID:23393330

  1. Contribution of phospholipase D in endothelin-1-mediated extracellular signal-regulated kinase activation and proliferation in rat uterine leiomyoma cells.

    Science.gov (United States)

    Robin, Philippe; Chouayekh, Sondes; Bole-Feysot, Christine; Leiber, Denis; Tanfin, Zahra

    2005-01-01

    Endothelin (ET)-1 is a mitogenic factor in numerous cell types, including rat myometrial cells. In the present study, we investigated the potential role of ET-1 in the proliferation of tumoral uterine smooth muscle cells (ELT-3 cells). We found that ET-1 exerted a more potent mitogenic effect in ELT-3 cells than in normal myometrial cells, as indicated by the increase in [3H]thymidine incorporation, cell number, and bromodeoxyuridine incorporation. The ET-1 was more efficient than platelet-derived growth factor and epidermal growth factor to stimulate proliferation. The ET-1-mediated cell proliferation was inhibited in the presence of U0126, a specific inhibitor of (mitogen-activated protein kinase ERK kinase), indicating that extracellular signal-regulated kinase (ERK) activation is involved. Additionally, ET-1 induced the activation of phospholipase (PL) D, leading to the synthesis of phosphatidic acid (PA). The ET-1-induced activation of PLD was twofold higher in ELT-3 cells compared to that in normal cells. The two cell types expressed mRNA for PLD1a and PLD2, whereas PLD1b was expressed only in ELT-3 cells. The exposure of cells to butan-1-ol reduced ET-1-mediated production of PA by PLD and partially inhibited ERK activation and DNA synthesis. Addition of exogenous PLD or PA in the medium reproduced the effect of ET-1 on ERK activation and cell proliferation. Collectively, these data indicate that ET-1 is a potent mitogenic factor in ELT-3 cells via a signaling pathway involving a PLD-dependent activation of ERK. This highlights the potential role of ET-1 in the development of uterine leiomyoma, and it reinforces the role of PLD in tumor growth. PMID:15355882

  2. Tissue kallikrein induces SH-SY5Y cell proliferation via epidermal growth factor receptor and extracellular signal-regulated kinase1/2 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Zhengyu [Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200040 (China); Department of Neurology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200437 (China); Yang, Qi; Cui, Mei; Liu, Yanping [Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200040 (China); Wang, Tao; Zhao, Hong [Department of Neurology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200437 (China); Dong, Qiang, E-mail: qiang_dong163@163.com [Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200040 (China)

    2014-03-28

    Highlights: • TK promotes EGFR phosphorylation in SH-SY5Y cells. • TK activates ERK1/2 and p38 phosphorylation in SH-SY5Y cells. • TK mediates SH-SY5Y cell proliferation via EGFR and ERK1/2 pathway. - Abstract: Tissue kallikrein (TK) is well known to take most of its biological functions through bradykinin receptors. In the present study, we found a novel signaling pathway mediated by TK through epidermal growth factor receptor (EGFR) in human SH-SY5Y cells. We discovered that TK facilitated the activation of EGFR, extracellular signal-regulated kinase (ERK) 1/2 and p38 cascade. Interestingly, not p38 but ERK1/2 phosphorylation was severely compromised in cells depleted of EGFR. Nevertheless, impairment of signaling of ERK1/2 seemed not to be restricted to EGFR phosphorylation. We also observed that TK stimulation could induce SH-SY5Y cell proliferation, which was reduced by EGFR down-regulation or ERK1/2 inhibitor. Overall, our findings provided convincing evidence that TK could mediate cell proliferation via EGFR and ERK1/2 pathway in vitro.

  3. Tissue kallikrein induces SH-SY5Y cell proliferation via epidermal growth factor receptor and extracellular signal-regulated kinase1/2 pathway

    International Nuclear Information System (INIS)

    Highlights: • TK promotes EGFR phosphorylation in SH-SY5Y cells. • TK activates ERK1/2 and p38 phosphorylation in SH-SY5Y cells. • TK mediates SH-SY5Y cell proliferation via EGFR and ERK1/2 pathway. - Abstract: Tissue kallikrein (TK) is well known to take most of its biological functions through bradykinin receptors. In the present study, we found a novel signaling pathway mediated by TK through epidermal growth factor receptor (EGFR) in human SH-SY5Y cells. We discovered that TK facilitated the activation of EGFR, extracellular signal-regulated kinase (ERK) 1/2 and p38 cascade. Interestingly, not p38 but ERK1/2 phosphorylation was severely compromised in cells depleted of EGFR. Nevertheless, impairment of signaling of ERK1/2 seemed not to be restricted to EGFR phosphorylation. We also observed that TK stimulation could induce SH-SY5Y cell proliferation, which was reduced by EGFR down-regulation or ERK1/2 inhibitor. Overall, our findings provided convincing evidence that TK could mediate cell proliferation via EGFR and ERK1/2 pathway in vitro

  4. IL-1β-induced matrix metalloproteinase-13 is activated by a disintegrin and metalloprotease-28-regulated proliferation of human osteoblast-like cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Kawai, Rie; Yamaguchi, Hideyuki; Hiyama, Taiki; Kinoshita, Katsue; Hase, Naoko; Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya, Aichi 464-8650 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya, Aichi 464-8650 (Japan); Nakamura, Hiroshi [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan)

    2014-04-15

    We reported previously that matrix metalloproteinase (MMP)-13 accelerates bone remodeling in oral periradicular lesions, and indicated a potentially unique role for MMP-13 in wound healing and regeneration of alveolar bone. The ADAM (a disintegrin and metalloprotease) family is a set of multifunctional cell surface and secreted glycoproteins, of which ADAM-28 has been localized in bone and bone-like tissues. In this study, we show that interleukin (IL)-1β induces the expression of MMP-13 and ADAM-28 in homogeneous α7 integrin-positive human skeletal muscle stem cell (α7{sup +}hSMSC)-derived osteoblast-like (α7{sup +}hSMSC-OB) cells, and promotes proliferation while inhibiting apoptosis in these cells. At higher concentrations, however, IL-1β failed to induce the expression of these genes and caused an increase in apoptosis. We further employed ADAM-28 small interfering RNA (siRNA) to investigate whether IL-1β-induced MMP-13 expression is linked to this IL-1β-mediated changes in cell proliferation and apoptosis. Silencing ADAM-28 expression potently suppressed IL-1β-induced MMP-13 expression and activity, decreased cell proliferation and increased apoptosis in α7{sup +}hSMSC-OB cells. In contrast, MMP-13 siRNA had no effect on ADAM-28 expression, suggesting ADAM-28 regulates MMP-13. Exogenous MMP-13 induced α7{sup +}hSMSC-OB cell proliferation and could rescue ADAM-28 siRNA-induced apoptosis, and we found that proMMP-13 is partially cleaved into its active form by ADAM-28 in vitro. Overall, our results suggest that IL-1β-induced MMP-13 expression and changes in cell proliferation and apoptosis in α7{sup +}hSMSC-OB cells are regulated by ADAM-28. - Highlights: • IL-1β induces the MMP-13 and ADAM-28 expression in human osteoblast-like cells. • IL-1β-induced MMP-13 expression increases proliferation and decreased apoptosis. • MMP-13 expression induced by IL-1β is regulated by ADAM-28. • proMMP-13 appears to be cleaved into its active form via

  5. IL-1β-induced matrix metalloproteinase-13 is activated by a disintegrin and metalloprotease-28-regulated proliferation of human osteoblast-like cells

    International Nuclear Information System (INIS)

    We reported previously that matrix metalloproteinase (MMP)-13 accelerates bone remodeling in oral periradicular lesions, and indicated a potentially unique role for MMP-13 in wound healing and regeneration of alveolar bone. The ADAM (a disintegrin and metalloprotease) family is a set of multifunctional cell surface and secreted glycoproteins, of which ADAM-28 has been localized in bone and bone-like tissues. In this study, we show that interleukin (IL)-1β induces the expression of MMP-13 and ADAM-28 in homogeneous α7 integrin-positive human skeletal muscle stem cell (α7+hSMSC)-derived osteoblast-like (α7+hSMSC-OB) cells, and promotes proliferation while inhibiting apoptosis in these cells. At higher concentrations, however, IL-1β failed to induce the expression of these genes and caused an increase in apoptosis. We further employed ADAM-28 small interfering RNA (siRNA) to investigate whether IL-1β-induced MMP-13 expression is linked to this IL-1β-mediated changes in cell proliferation and apoptosis. Silencing ADAM-28 expression potently suppressed IL-1β-induced MMP-13 expression and activity, decreased cell proliferation and increased apoptosis in α7+hSMSC-OB cells. In contrast, MMP-13 siRNA had no effect on ADAM-28 expression, suggesting ADAM-28 regulates MMP-13. Exogenous MMP-13 induced α7+hSMSC-OB cell proliferation and could rescue ADAM-28 siRNA-induced apoptosis, and we found that proMMP-13 is partially cleaved into its active form by ADAM-28 in vitro. Overall, our results suggest that IL-1β-induced MMP-13 expression and changes in cell proliferation and apoptosis in α7+hSMSC-OB cells are regulated by ADAM-28. - Highlights: • IL-1β induces the MMP-13 and ADAM-28 expression in human osteoblast-like cells. • IL-1β-induced MMP-13 expression increases proliferation and decreased apoptosis. • MMP-13 expression induced by IL-1β is regulated by ADAM-28. • proMMP-13 appears to be cleaved into its active form via ADAM-28

  6. Prolactin-induced protein (PIP regulates proliferation of luminal A type breast cancer cells in an estrogen-independent manner.

    Directory of Open Access Journals (Sweden)

    Sanjeev K Baniwal

    Full Text Available Prolactin-induced Protein (PIP, an aspartyl protease unessential for normal mammalian cell function, is required for the proliferation and invasion of some breast cancer (BCa cell types. Because PIP expression is particularly high in the Luminal A BCa subtype, we investigated the roles of PIP in the related T47D BCa cell line. Nucleic acid and antibody arrays were employed to screen effects of PIP silencing on global gene expression and activation of receptor tyrosine kinases (RTKs, respectively. Expression of PIP-stimulated genes, as defined in the T47D cell culture model, was well correlated with the expression of PIP itself across a cohort of 557 mRNA profiles of diverse BCa tumors, and bioinformatics analysis revealed cJUN and cMYC as major nodes in the PIP-dependent gene network. Among 71 RTKs tested, PIP silencing resulted in decreased phosphorylation of focal adhesion kinase (FAK, ephrin B3 (EphB3, FYN, and hemopoietic cell kinase (HCK. Ablation of PIP also abrogated serum-induced activation of the downstream serine/threonine kinases AKT, ERK1/2, and JNK1. Consistent with these results, PIP-depleted cells exhibited defects in adhesion to fibronectin, cytoskeletal stress fiber assembly and protein secretion. In addition, PIP silencing abrogated the mitogenic response of T47D BCa cells to estradiol (E2. The dependence of BCa cell proliferation was unrelated, however, to estrogen signaling because: 1 PIP silencing did not affect the transcriptional response of estrogen target genes to hormone treatment, and 2 PIP was required for the proliferation of tamoxifen-resistant BCa cells. Pharmacological inhibition of PIP may therefore serve the bases for both augmentation of existing therapies for hormone-dependent tumors and the development of novel therapeutic approaches for hormone-resistant BCa.

  7. RUNX3-mediated up-regulation of miR-29b suppresses the proliferation and migration of gastric cancer cells by targeting KDM2A.

    Science.gov (United States)

    Kong, Ye; Zou, Shuiyan; Yang, Fenghua; Xu, Xia; Bu, Wenhong; Jia, Jihui; Liu, Zhifang

    2016-10-10

    RUNX3 is a transcriptional factor that has been shown to regulate protein-coding gene expression at the transcriptional level. However, the regulation of RUNX3 on miRNAs is not fully understood. In this study, we used miRNA microarray to identify the miRNAs that are regulated by RUNX3 and found that miR-29b showed the most up-regulation in RUNX3 over-expressed cells compared with the control cells. We used qRT-PCR to confirm the miRNA microarray results in several gastric cancer cells and found that RUNX3 could bind to the miR-29b promoter directly and cooperate with Smad3 to increase the promoter activity of miR-29b. In the clinical setting, both RUNX3 and miR-29b are down-regulated significantly in human gastric cancer tissues. A positive correlation between miR-29b and RUNX3 was found in the gastric cancer tissues. Additionally, we found that miR-29b suppressed the proliferation and metastasis of gastric cancer cells by directly targeting KDM2A. The miR-29b/KDM2A axis was involved in the RUNX3-mediated inhibition of gastric cancer cell proliferation and metastasis. Taken together, our results suggested that RUNX3-mediated up-regulation of miR-29b inhibited the proliferation and migration of gastric cancer cells by targeting KDM2A, representing a novel molecular mechanism for the tumor suppression action of RUNX3.

  8. Identification of glucocorticoid-induced leucine zipper as a key regulator of tumor cell proliferation in epithelial ovarian cancer

    Directory of Open Access Journals (Sweden)

    Fernandez Hervé

    2009-10-01

    Full Text Available Abstract Background Little is known about the molecules that contribute to tumor progression of epithelial ovarian cancer (EOC, currently a leading cause of mortality from gynecological malignancies. Glucocorticoid-Induced Leucine Zipper (GILZ, an intracellular protein widely expressed in immune tissues, has been reported in epithelial tissues and controls some of key signaling pathways involved in tumorigenesis. However, there has been no report on GILZ in EOC up to now. The objectives of the current study were to examine the expression of GILZ in EOC and its effect on tumor cell proliferation. Results GILZ expression was measured by immunohistochemical staining in tissue sections from 3 normal ovaries, 7 benign EOC and 50 invasive EOC. GILZ was not detected on the surface epithelium of normal ovaries and benign tumors. In contrast, it was expressed in the cytoplasm of tumor cells in 80% EOC specimens. GILZ immunostaining scores correlated positively to the proliferation marker Ki-67 (Spearman test in univariate analysis, P P Conclusion The present study is the first to identify GILZ as a molecule produced by ovarian cancer cells that promotes cell cycle progression and proliferation. Our findings clearly indicate that GILZ activates AKT, a crucial signaling molecule in tumorigenesis. GILZ thus appears as a potential key molecule in EOC.

  9. EZH2-specific microRNA-98 inhibits human ovarian cancer stem cell proliferation via regulating the pRb-E2F pathway.

    Science.gov (United States)

    Liu, Te; Hou, Lengchen; Huang, Yongyi

    2014-07-01

    The Polycomb group protein, enhancer of zeste homolog 2 (EZH2), plays an important role in transcriptional regulation through chromatin remodeling and interactions with other transcription factors to control cell proliferation and embryonic development. Previous study has shown that EZH2 is important for cell cycle regulation and is highly expressed in human ovarian cancer. Loss of EZH2 inhibits growth of ovarian cancer as well as other human carcinomas. In this study, an expression plasmid of EZH2-targeted microRNA-98 was constructed and transfected into human ovarian cancer stem cells (OCSCs). Seventy-two hours after transfection, cell growth was inhibited and arrested at the G0/G1 transition. p21(CIPI/WAF1) was up-regulated, while the CDK2/cyclin E complex and c-Myc were down-regulated. Most importantly, expression levels of E2F1, retinoblastoma protein (pRb), and histone deacetylase 1 (HDAC1) in the pRb-E2F signaling pathway had changed. Furthermore, microRNA-98 suppressed the growth of OCSCs xenograft tumors. Our findings suggest that EZH2-specific microRNA-98 can effectively inhibit cell proliferation in vitro and regulate the pRb-E2F pathway in human OCSCs.

  10. The lens equator: a platform for molecular machinery that regulates the switch from cell proliferation to differentiation in the vertebrate lens.

    Science.gov (United States)

    Mochizuki, Toshiaki; Masai, Ichiro

    2014-06-01

    The vertebrate lens is a transparent, spheroidal tissue, located in the anterior region of the eye that focuses visual images on the retina. During development, surface ectoderm associated with the neural retina invaginates to form the lens vesicle. Cells in the posterior half of the lens vesicle differentiate into primary lens fiber cells, which form the lens fiber core, while cells in the anterior half maintain a proliferative state as a monolayer lens epithelium. After formation of the primary fiber core, lens epithelial cells start to differentiate into lens fiber cells at the interface between the lens epithelium and the primary lens fiber core, which is called the equator. Differentiating lens fiber cells elongate and cover the old lens fiber core, resulting in growth of the lens during development. Thus, lens fiber differentiation is spatially regulated and the equator functions as a platform that regulates the switch from cell proliferation to cell differentiation. Since the 1970s, the mechanism underlying lens fiber cell differentiation has been intensively studied, and several regulatory factors that regulate lens fiber cell differentiation have been identified. In this review, we focus on the lens equator, where these regulatory factors crosstalk and cooperate to regulate lens fiber differentiation. Normally, lens epithelial cells must pass through the equator to start lens fiber differentiation. However, there are reports that when the lens epithelium structure is collapsed, lens fiber cell differentiation occurs without passing the equator. We also discuss a possible mechanism that represses lens fiber cell differentiation in lens epithelium.

  11. Insulin-like growth factor binding protein-3 is required for the regulation of rat oval cell proliferation and differentiation in the 2AAF/PHX model

    Directory of Open Access Journals (Sweden)

    Nicole C Steiger-Luther

    2010-02-01

    RNA (siRNA treated animals determined that expression of TGFβ family members, including TGF-βRII and Smads 2–4, were significantly downregulated compared to animals at day 9 post-PHx alone or animals that received negative control siRNA. In conclusion, IGFBP-3 may function as a potent chemoattractant of oval cells during specific types of liver regeneration and may be involved in regulating oval cell proliferation and differentiation in vivo via the TGF-β pathway.Keywords: hepatic stem cells, transforming growth factor-beta, N-2-acetylaminofluorene (2AAF, partial hepatectomy (PHx

  12. MiR-138 promotes smooth muscle cells proliferation and migration in db/db mice through down-regulation of SIRT1

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Juan [Department of Gynecology, Changzhou Maternity and Children Health Hospital, Changzhou, Jiangsu 213003 (China); Li, Li; Yun, Hui-fang [Department of Anesthesiology, Changzhou No. 2 People' s Hospital, Changzhou, Jiangsu 213003 (China); Han, Ye-shan, E-mail: yeshanhan123@163.com [Department of Anesthesiology, Changzhou No. 2 People' s Hospital, Changzhou, Jiangsu 213003 (China)

    2015-08-07

    Background: Diabetic vascular smooth muscle cells (VSMCs) exhibit significantly increased rates of proliferation and migration, which was the most common pathological change in atherosclerosis. In addition, the study about the role for miRNAs in the regulation of VSMC proliferation is just beginning to emerge and additional miRNAs involved in VSMC proliferation modulation should be identified. Methods: The expression of miR-138 and SIRT1 were examined in SMCs separated from db/db mice and in SMC lines C-12511 exposed to high glucose with qRT-PCR and western blot. The regulation of miR-138 on the expression of SMCs was detected with luciferase report assay. VSMCs proliferation and migration assays were performed to examine the effect of miR-138 inhibitor on VSMCs proliferation and migration. Results: We discovered that higher mRNA level of miR-138 and reduced expression of SIRT1 were observed in SMCs separated from db/db mice and in SMC lines C-12511. Moreover, luciferase report assay showed that the activity of SIRT1 3′-UTR was highly increased by miR-138 inhibitor and reduced by miR-138 mimic. In addition, we examined that the up-regulation of NF-κB induced by high glucose in SMCs was reversed by resveratrol and miR-138 inhibitor. MTT and migration assays showed that miR-138 inhibitor attenuated the proliferation and migration of smooth muscle cells. Conclusion: In this study, we revealed that miR-138 might promote proliferation and migration of SMC in db/db mice through suppressing the expression of SIRT1. - Highlights: • Higher mRNA level of miR-138 was observed in SMCs from db/db mice. • The mRNA and protein level of SIRT1 in SMCs from db/db mice were greatly reduced. • miR-138 could regulate the expression of SIRT1 in SMCs. • SIRT1 overexpression reversed the up-regulation of acetylized p65 and NF-κB induced by high glucose. • MiR-138 inhibitor reversed VSMCs proliferation and migration induced by high glucose.

  13. MiR-138 promotes smooth muscle cells proliferation and migration in db/db mice through down-regulation of SIRT1

    International Nuclear Information System (INIS)

    Background: Diabetic vascular smooth muscle cells (VSMCs) exhibit significantly increased rates of proliferation and migration, which was the most common pathological change in atherosclerosis. In addition, the study about the role for miRNAs in the regulation of VSMC proliferation is just beginning to emerge and additional miRNAs involved in VSMC proliferation modulation should be identified. Methods: The expression of miR-138 and SIRT1 were examined in SMCs separated from db/db mice and in SMC lines C-12511 exposed to high glucose with qRT-PCR and western blot. The regulation of miR-138 on the expression of SMCs was detected with luciferase report assay. VSMCs proliferation and migration assays were performed to examine the effect of miR-138 inhibitor on VSMCs proliferation and migration. Results: We discovered that higher mRNA level of miR-138 and reduced expression of SIRT1 were observed in SMCs separated from db/db mice and in SMC lines C-12511. Moreover, luciferase report assay showed that the activity of SIRT1 3′-UTR was highly increased by miR-138 inhibitor and reduced by miR-138 mimic. In addition, we examined that the up-regulation of NF-κB induced by high glucose in SMCs was reversed by resveratrol and miR-138 inhibitor. MTT and migration assays showed that miR-138 inhibitor attenuated the proliferation and migration of smooth muscle cells. Conclusion: In this study, we revealed that miR-138 might promote proliferation and migration of SMC in db/db mice through suppressing the expression of SIRT1. - Highlights: • Higher mRNA level of miR-138 was observed in SMCs from db/db mice. • The mRNA and protein level of SIRT1 in SMCs from db/db mice were greatly reduced. • miR-138 could regulate the expression of SIRT1 in SMCs. • SIRT1 overexpression reversed the up-regulation of acetylized p65 and NF-κB induced by high glucose. • MiR-138 inhibitor reversed VSMCs proliferation and migration induced by high glucose

  14. The bHLH factors Dpn and members of the E(spl complex mediate the function of Notch signalling regulating cell proliferation during wing disc development

    Directory of Open Access Journals (Sweden)

    Beatriz P. San Juan

    2012-05-01

    The Notch signalling pathway plays an essential role in the intricate control of cell proliferation and pattern formation in many organs during animal development. In addition, mutations in most members of this pathway are well characterized and frequently lead to tumour formation. The Drosophila imaginal wing discs have provided a suitable model system for the genetic and molecular analysis of the different pathway functions. During disc development, Notch signalling at the presumptive wing margin is necessary for the restricted activation of genes required for pattern formation control and disc proliferation. Interestingly, in different cellular contexts within the wing disc, Notch can either promote cell proliferation or can block the G1-S transition by negatively regulating the expression of dmyc and bantam micro RNA. The target genes of Notch signalling that are required for these functions have not been identified. Here, we show that the Hes vertebrate homolog, deadpan (dpn, and the Enhancer-of-split complex (E(splC genes act redundantly and cooperatively to mediate the Notch signalling function regulating cell proliferation during wing disc development.

  15. Mir-184 post-transcriptionally regulates SOX7 expression and promotes cell proliferation in human hepatocellular carcinoma.

    Directory of Open Access Journals (Sweden)

    Geng-Gang Wu

    Full Text Available Hepatocellular carcinoma (HCC is one of the most common human malignancies and the third leading cause of cancer mortality worldwide. The development and progression of HCC is a complicated process, involving the deregulation of multiple genes that are essential to cell biological processes. Recently, microRNAs (miRNAs have been suggested to be closely associated with tumorigenesis. Our study showed that miR-184 is upregulated in HCC cell lines and tissues. Overexpression of miR-184 in HCC cells increased cell proliferation, tumorigenicity, and cell cycle progression, whereas inhibition of miR-184 reduced cell proliferation, tumorigenicity, and cell cycle progression. Additionally, we identified SOX7 as a direct target of miR-184. Ectopic expression of miR-184 led to downregulation of the SOX7 protein, resulting in upregulation of c-Myc, Cyclin D1, and phosphorylation of Rb. Our findings suggested that miR-184 represents a potential onco-miR and plays an important role in HCC progression by suppressing SOX7 expression.

  16. Effects of glucose and insulin on the H9c2 (2-1) cell proliferation may be mediated through regulating glucose transporter 4 expression

    Institute of Scientific and Technical Information of China (English)

    LIU Qian; HUANG Qing-xian; LOU Fu-chen; ZHANG Li; WANG Kun; YU Shan; XU Hua

    2013-01-01

    RNA level in HG1 group was higher on the first day but lower on the second and third day (P <0.05).In HG1,HG2 and HG3 groups,GLUT4 mRNA level had a negative correlation with the level of glucose (P <0.05).GLUT4 mRNA in INSc subgroups was lower than that in INSh subgroups (P <0.05).The expression of GLUT4 protein was similar to that of GLUT4 mRNA.There was a positive correlation between H9c2 cell proliferation and GLUT4 expression (P <0.02).Conclusions Glucose levels could regulate glucose uptake in myocardial cells through influencing GLUT4 expression,and thus affected the cell proliferation and cell function.Insulin levels could affect the myocardial cell function by regulating GLUT4 expression.Effects of glucose and insulin on the myocardial cells proliferation might be mediated through regulating GLUT4 expression.There may be a mechanism of hyperglycemia pre-accommodation (HGPA) in myocardial cells mediated through regulation of GLUT4 expression.

  17. A critical role of IFNγ in priming MSC-mediated suppression of T cell proliferation through up-regulation of B7-H1

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Bone-marrow-derived mesenchymal stem cells (MSCs) have been shown to possess immunosuppressive properties, e.g., by inhibiting T cell proliferation. Activated T cells can also enhance the immunosuppression ability of MSCs. The precise mechanisms underlying MSC-mediated immunosuppression remain largely undefined, although both cell-cell contact and soluble factors have been implicated; nor is it clear how the immunosuppressive property of MSCs is modulated by T cells. Using MSCs isolated from mouse bone marrow, we show here that interferon gamma (IFNγ), a well-known proinflammatory cytokine produced by activated T cells, plays an important role in priming the immunosuppressive property of MSCs. Mechanistically, IFNγ acts directly on MSCs and leads to up-regulation of B7-H1, an inhibitory surface molecule in these stem cells. MSCs primed by activated T cells derived from IFNγ-/- mouse exhibited dramatically reduced ability to suppress T cell proliferation, a defect that can be rescued by supplying exogenous IFNy. Moreover, siRNA-mediated knockdown of B7-H1 in MSCs abolished immunosuppression by these cells. Taken together, our results suggest that IFNy plays a critical role in triggering the immunosuppresion by MSCs through upregulating B7-H1 in these cells, and provide evidence supporting the cell-cell contact mechanism in MSC-mediated immunosuppression.

  18. Overexpression of cell cycle regulator CDCA3 promotes oral cancer progression by enhancing cell proliferation with prevention of G1 phase arrest

    International Nuclear Information System (INIS)

    Cell division cycle associated 3 (CDCA3), part of the Skp1-cullin-F-box (SCF) ubiquitin ligase, refers to a trigger of mitotic entry and mediates destruction of the mitosis inhibitory kinase. Little is known about the relevance of CDCA3 to human malignancy including oral squamous cell carcinoma (OSCC). We aimed to characterize the expression state and function of CDCA3 in OSCC. We evaluated CDCA3 mRNA and protein expression in both OSCC-derived cell lines and primary OSCCs and performed functional analyses of CDCA3 in OSCC-derived cells using the shRNA system. The CDCA3 expression at both the mRNA and protein levels was frequently up-regulated in all cell lines examined and primary tumors (mRNA, 51/69, 74 %; protein, 79/95, 83 %) compared to normal controls (p < 0.001). In contrast, no significant level of CDCA3 protein expression was seen in oral premalignant lesions (OPLs) (n = 20) compared with the expression in OSCCs. Among the clinical variables analyzed, the CDCA3 expression status was closely related to tumor size (p < 0.05). In addition, suppression of CDCA3 expression with shRNA significantly (p < 0.05) inhibited cellular proliferation compared with the control cells by arresting cell-cycle progression at the G1 phase. Further, there was up-regulation of the cyclin-dependent kinase inhibitors (p21Cip1, p27Kip1, p15INK4B, and p16INK4A) in the knockdown cells. The current results showed that overexpression of CDCA3 occurs frequently during oral carcinogenesis and this overexpression might be associated closely with progression of OSCCs by preventing the arrest of cell-cycle progression at the G1 phase via decreased expression of the cyclin-dependent kinase inhibitors

  19. Autophagy regulates T lymphocyte proliferation through selective degradation of the cell-cycle inhibitor CDKN1B/p27Kip1.

    Science.gov (United States)

    Jia, Wei; He, Ming-Xiao; McLeod, Ian X; Guo, Jian; Ji, Dong; He, You-Wen

    2015-01-01

    The highly conserved cellular degradation pathway, macroautophagy, regulates the homeostasis of organelles and promotes the survival of T lymphocytes. Previous results indicate that Atg3-, Atg5-, or Pik3c3/Vps34-deficient T cells cannot proliferate efficiently. Here we demonstrate that the proliferation of Atg7-deficient T cells is defective. By using an adoptive transfer and Listeria monocytogenes (LM) mouse infection model, we found that the primary immune response against LM is intrinsically impaired in autophagy-deficient CD8(+) T cells because the cell population cannot expand after infection. Autophagy-deficient T cells fail to enter into S-phase after TCR stimulation. The major negative regulator of the cell cycle in T lymphocytes, CDKN1B, is accumulated in autophagy-deficient naïve T cells and CDKN1B cannot be degraded after TCR stimulation. Furthermore, our results indicate that genetic deletion of one allele of CDKN1B in autophagy-deficient T cells restores proliferative capability and the cells can enter into S-phase after TCR stimulation. Finally, we found that natural CDKN1B forms polymers and is physiologically associated with the autophagy receptor protein SQSTM1/p62 (sequestosome 1). Collectively, autophagy is required for maintaining the expression level of CDKN1B in naïve T cells and selectively degrades CDKN1B after TCR stimulation.

  20. Blue light inhibits proliferation of melanoma cells

    Science.gov (United States)

    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.

  1. Src family kinase inhibitor PP2 efficiently inhibits cervical cancer cell proliferation through down-regulating phospho-Src-Y416 and phospho-EGFR-Y1173.

    Science.gov (United States)

    Kong, Lu; Deng, Zhihong; Shen, Haiying; Zhang, Yuxiang

    2011-02-01

    Tyrosine (Y) kinases inhibitors have been approved for targeted treatment of cancer. However, their clinical use is limited to some cancers and the mechanism of their action remains unclear. Previous study has indicated that PP2, a selective inhibitor of the Src family of non-receptor tyrosine kinases (nRTK), efficiently repressed cervical cancer growth in vitro and in vivo. In this regard, our aims are to explore the mechanism of PP2 on cervical cancer cell growth inhibition by investigating the suppressive divergence among PP1, PP2, and a negative control compound PP3. MTT results showed that three compounds had different inhibitory effects on proliferation of two cervical cancer cells, HeLa and SiHa, and PP2 was most efficient in a time- and dose-dependent manner. Moreover, we found 10 μM PP2 down-regulated pSrc-Y416 (P < 0.05), pEGFR-Y845 (P < 0.05), and -Y1173 (P < 0.05) expression levels, while 10 μM PP1 down-regulated pSrc-Y416 (P < 0.05) and pEGFR-Y845 (P < 0.05), but not pEGFR-Y1173; 10 μM PP3 down-regulated only pEGFR-Y1173 (P < 0.05). PP2 could modulate cell cycle arrest by up-regulating p21(Cip1) and p27(Kip1) in both HeLa and SiHa cells and down-regulating expression of cyclin A, and cyclin dependent kinase-2, -4 (Cdk-2, -4) in HeLa and of cyclin B and Cdk-2 in SiHa. Our results indicate that Src pathway and EGFR pathway play different roles in the proliferation of cervical cancer cells and PP2 efficiently reduces cervical cancer cell proliferation by reduction of both Src and EGFR activity.

  2. Somatostatin and opioid receptors do not regulate proliferation or apoptosis of the human multiple myeloma U266 cells

    Directory of Open Access Journals (Sweden)

    Allouche Stéphane

    2009-06-01

    Full Text Available Abstract Background opioid and somatostatin receptors (SSTRs that can assemble as heterodimer were individually reported to modulate malignant cell proliferation and to favour apoptosis. Materials and methods: SSTRs and opioid receptors expression were examined by RT-PCR, western-blot and binding assays, cell proliferation was studied by XTT assay and propidium iodide (PI staining and apoptosis by annexin V-PI labelling. Results almost all human malignant haematological cell lines studied here expressed the five SSTRs. Further experiments were conducted on the human U266 multiple myeloma cells, which express also μ-opioid receptors (MOP-R. XTT assays and cell cycle studies provide no evidence for a significant effect upon opioid or somatostatin receptors stimulation. Furthermore, neither direct effect nor potentiation of the Fas-receptor pathway was detected on apoptosis after these treatments. Conclusion these data suggest that SSTRs or opioid receptors expression is not a guaranty for an anti-tumoral action in U266 cell line.

  3. FoxO1a and SIRT1 in vasculo-proliferative diseases : Major roles in regulating smooth muscle cell proliferation, migration and survival

    OpenAIRE

    König, Heike

    2009-01-01

    Vasculo-proliferative disorders such as atherosclerosis, postangioplasty restenosis, and pulmonary hypertension are complex processes that are especially related to vascular smooth muscle cells (VSMCs)45, 78. In the arterial media, VSMC are normally quiescent, however, for the development and progression of the above mentioned diseases it is prerequisite that quiescent VSMCs start to proliferate, migrate and undergo apoptosis. Different extracellular stimuli are responsible for regulating VSM...

  4. Eurycomanone and Eurycomanol from Eurycoma longifolia Jack as Regulators of Signaling Pathways Involved in Proliferation, Cell Death and Inflammation

    Directory of Open Access Journals (Sweden)

    Shéhérazade Hajjouli

    2014-09-01

    Full Text Available Eurycomanone and eurycomanol are two quassinoids from the roots of Eurycoma longifolia Jack. The aim of this study was to assess the bioactivity of these compounds in Jurkat and K562 human leukemia cell models compared to peripheral blood mononuclear cells from healthy donors. Both eurycomanone and eurycomanol inhibited Jurkat and K562 cell viability and proliferation without affecting healthy cells. Interestingly, eurycomanone inhibited NF-κB signaling through inhibition of IκBα phosphorylation and upstream mitogen activated protein kinase (MAPK signaling, but not eurycomanol. In conclusion, both quassinoids present differential toxicity towards leukemia cells, and the presence of the α,β-unsaturated ketone in eurycomanone could be prerequisite for the NF-κB inhibition.

  5. Naive CD4 T Cell Proliferation Is Controlled by Mammalian Target of Rapamycin Regulation of GRAIL Expression1

    OpenAIRE

    Lin, Jack T; Lineberry, Neil B.; Kattah, Michael G; Su, Leon L.; Utz, Paul J; Fathman, C. Garrison; Wu, Linda

    2009-01-01

    In this study, we demonstrate that the E3 ubiquitin ligase gene related to anergy in lymphocytes (GRAIL) is expressed in quiescent naive mouse and human CD4 T cells and has a functional role in inhibiting naive T cell proliferation. Following TCR engagement, CD28 costimulation results in the expression of IL-2 whose signaling through its receptor activates the Akt-mammalian target of rapamycin (mTOR) pathway. Activation of mTOR allows selective mRNA translation, including the epistatic regula...

  6. EGCG Inhibits Proliferation, Invasiveness and Tumor Growth by Up-Regulation of Adhesion Molecules, Suppression of Gelatinases Activity, and Induction of Apoptosis in Nasopharyngeal Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Chih-Yeu Fang

    2015-01-01

    Full Text Available (−-Epigallocatechin-3-gallate (EGCG, a major green tea polyphenol, has been shown to inhibit the proliferation of a variety of tumor cells. Epidemiological studies have shown that drinking green tea can reduce the incidence of nasopharyngeal carcinoma (NPC, yet the underlying mechanism is not well understood. In this study, the inhibitory effect of EGCG was tested on a set of Epstein Barr virus-negative and -positive NPC cell lines. Treatment with EGCG inhibited the proliferation of NPC cells but did not affect the growth of a non-malignant nasopharyngeal cell line, NP460hTert. Moreover, EGCG treated cells had reduced migration and invasive properties. The expression of the cell adhesion molecules E-cadherin and β-catenin was found to be up-regulated by EGCG treatment, while the down-regulation of matrix metalloproteinases (MMP-2 and MMP-9 were found to be mediated by suppression of extracellular signal-regulated kinase (ERK phosphorylation and AP-1 and Sp1 transactivation. Spheroid formation by NPC cells in suspension was significantly inhibited by EGCG. Oral administration of EGCG was capable of suppressing tumor growth in xenografted mice bearing NPC tumors. Treatment with EGCG was found to elevate the expression of p53 and p21, and eventually led to apoptosis of NPC cells via caspase 3 activation. The nuclear translocation of NF-κB and β-catenin was also suppressed by EGCG treatment. These results indicate that EGCG can inhibit the proliferation and invasiveness, and induce apoptosis, of NPC cells, making it a promising agent for chemoprevention or adjuvant therapy of NPC.

  7. BAFF induces spleen CD4{sup +} T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Fang; Chen, Rongjing [Department of Orthodontics, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Liu, Baojun [Laboratory of Lung, Inflammation and Cancers, Huashan Hospital, Fudan University, Shanghai (China); Zhang, Xiaoping [Department of Nuclear Medicine, Shanghai 10th People' s Hospital, Tongji University School of Medicine, Shanghai 200072 (China); Han, Junli; Wang, Haining [Department of General Dentistry, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Shen, Gang [Department of Orthodontics, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Tao, Jiang, E-mail: taojiang2012@yahoo.cn [Department of General Dentistry, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Firstly analyze the mechanism of BAFF and anti-CD3 co-stimulation on purified mouse splenic CD4{sup +} T cells. Black-Right-Pointing-Pointer Carrying out siRNA technology to study FOXO3A protein function. Black-Right-Pointing-Pointer Helpful to understand the T cell especially CD4{sup +} T cell's role in immunological reaction. -- Abstract: The TNF ligand family member 'B cell-activating factor belonging to the TNF family' (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4{sup +} spleen T cell proliferation when co-stimulated with anti-CD3. Expression of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4{sup +} T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4{sup +} spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4{sup +} T cell proliferation.

  8. Identification of protein kinase D2 as a pivotal regulator of endothelial cell proliferation, migration, and angiogenesis.

    Science.gov (United States)

    Hao, Qin; Wang, Linping; Zhao, Z Joe; Tang, Hua

    2009-01-01

    Angiogenesis, the formation of new blood vessels, plays a crucial role in normal physiological processes and in various pathological conditions. In the present study, we have investigated the physiological function of a newly described serine/threonine protein kinase D2 (PKD2) in aspects of endothelial cell biology involved in angiogenesis. We found that PKD2 was expressed in primary human endothelial cells from different tissues and was a critical PKD isoform mediating the phosphorylation of PKD substrates in endothelial cells. By using small interference RNAs that target different PKD2 regions, we found that silencing PKD2, but not PKD1 isoform, markedly inhibited the proliferation, migration, and in vitro angiogenesis of endothelial cells cultured in EGM-2 complete medium. We further showed that PKD2, but not PKD1, was required for the expression of vascular endothelial growth factor receptor-2 and fibroblast growth factor receptor-1 that are two key growth factor receptors involved in angiogenesis. These findings indicate that PKD2 plays a pivotal role in endothelial cell proliferation and migration necessary for angiogenesis at least in part through modulation of the expression of vascular endothelial growth factor receptor-2 and fibroblast growth factor receptor-1. PMID:19001381

  9. miR-155-dependent regulation of mammalian sterile 20-like kinase 2 (MST2) coordinates inflammation, oxidative stress and proliferation in vascular smooth muscle cells.

    Science.gov (United States)

    Yang, Zhan; Zheng, Bin; Zhang, Yu; He, Ming; Zhang, Xin-hua; Ma, Dong; Zhang, Ruo-nan; Wu, Xiao-li; Wen, Jin-kun

    2015-07-01

    In response to vascular injury, inflammation, oxidative stress, and cell proliferation often occur simultaneously in vascular tissues. We previously observed that microRNA-155 (miR-155), which is implicated in proliferation and inflammation is involved in neointimal hyperplasia; however, the molecular mechanisms by which it regulates these processes remain largely unknown. In this study, we observed that vascular smooth muscle cell (VSMC) proliferation and neointimal formation in wire-injured femoral arteries were reduced by the loss of miR-155 and increased by the gain of miR-155. The proliferative effect of miR-155 was also observed in cultured VSMCs. Notably, expression of the miR-155-target protein mammalian sterile 20-like kinase 2 (MST2) was increased in the injured arteries of miR-155-/- mice. miR-155 directly repressed MST2 and thus activated the extracellular signal-regulated kinase (ERK) pathway by promoting an interaction between RAF proto-oncogene serine/threonine-protein kinase (Raf-1) and mitogen-activated protein kinase kinase (MEK) and stimulating inflammatory and oxidative stress responses; together, these effects lead to VSMC proliferation and vascular remodeling. Our data reveal that MST2 mediates miR-155-promoted inflammatory and oxidative stress responses by altering the interaction of MEK with Raf-1 and MST2 in response to vascular injury. Therefore, suppression of endogenous miR-155 might be a novel therapeutic strategy for vascular injury and remodeling. PMID:25892184

  10. 5-Hydroxytryptamine-induced proliferation of pulmonary artery smooth muscle cells are extracellular signal-regulated kinase pathway depen-dent

    Institute of Scientific and Technical Information of China (English)

    Dan SONG; Huai-liang WANG; Shuang WANG; Xin-hua ZHANG

    2005-01-01

    Aim:To investigate the effect of 5-hydroxytryptamine transporter (5-HTT) inhibitor fluoxetine and antisense oligodeoxynucleotide (ODN) to extracelluar signal regulated kinases (ERKs) on pulmonary arterial smooth muscle cells (PASMCs) proliferation induced by 5-HT. Methods: Liposomal transfection was used to introduce ODNs to ERK1/2 into cultured rat PASMCs and the transfection effi ciency was measured by observing the uptake of the fluorecein isothiocynate (FITC)-labeled antisense ODN in PASMCs. The effects of 5-HTT selective inhibi tor fluoxetine and ODNs on the proliferation of PASMCs were evaluated by cell number counting and cell cycle analysis, and measured by microculture tetrazo lium (MTT) assay and flow cytometry (FCM), respectively. Results: Liposomes mediated the transfection of ODNs into PASMCs with high efficiency. MTT assay showed fluoxetine (10 μmol/L, 1 μmol/L, and 100 nmol/L) concentration dependently inhibited the proliferation of PASMCs induced by 5-HT (1 μmol/L) in vitro. The proliferation rate of PASMCs by 5-HT was significantly inhibited by pretreatment with ERK1/2 antisense ODN (0.2 μmol/L) from 251%± 18% to 86%±5% (P<0.01). Flow cytometric analysis of cell cycle distribution showed that the increase of 5-HT induced S phase fraction (SPF) and proliferation index (PI) were significantly inhibited by fluoxetine (1 μmol/L) or antisense ODN with SPF from 36%±4% to 26%±3% and 24%±4%, and PI from 34%±2% to 29%±2% and 24%±2%,respectively. Conclusion: 5-HTT mediates the mitogenic effect of 5-HT on PASMCs and the proliferation of PASMCs induced by 5-HT is dependent on ERKs signal pathway.

  11. Up-regulation of hypoxia inducible factor-1α by cobalt chloride correlates with proliferation and apoptosis in PC-2 cells

    Directory of Open Access Journals (Sweden)

    Dai Zhi-Jun

    2012-03-01

    Full Text Available Abstract Background The exact mechanism of the effects of hypoxia on the proliferation and apoptosis in carcinoma cells is still conflicting. This study investigated the variation of hypoxia-inducible factor-1α(HIF-1α expression and the apoptosis effect of hypoxia stimulated by cobalt chloride (CoCl2 in pancreatic cancer PC-2 cells. Methods PC-2 cells were cultured with different concentration (50-200 μmol/L of CoCl2 after 24-120 hours to simulate hypoxia in vitro. The proliferation of PC-2 cells was examined by MTT assay. The cellular morphology of PC-2 cells were observed by light inverted microscope and transmission electron microscope(EM. The expression of HIF-1α on mRNA and protein level was measured by semi-quantitive RT-PCR and Western blot analysis. Apoptosis of PC-2 cells were demonstrated by flow cytometry with Annexin V-FITC/PI double staining. Results MTT assay showed that the proliferation of PC-2 cells were stimulated in the first 72 h, while after treated over 72 h, a dose- dependent inhibition of cell growth could be observed. By using transmission electron microscope, swollen chondrosomes, accumulated chromatin under the nuclear membrane and apoptosis bodies were observed. Flow cytometer(FCM analysis showed the apoptosis rate was correlated with the dosage of CoCl2. RT-PCR and Western blot analysis indicated that hypoxia could up-regulate the expression of HIF-1α on both mRNA and protein levels. Conclusion Hypoxic microenvironment stimulated by CoCl2 could effectively induce apoptosis and influence cell proliferation in PC-2 cells, the mechanism could be related to up-expression of HIF-1α.

  12. Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Jin Young [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Hyoung Chul, E-mail: hcchoi@med.yu.ac.kr [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of)

    2011-05-06

    Highlights: {yields} Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. {yields} Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. {yields} Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. {yields} Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. {yields} Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

  13. Down-regulation of transcobalamin receptor TCblR/CD320 by siRNA inhibits cobalamin uptake and proliferation of cells in culture

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Shao-Chiang [School of Graduate Studies, SUNY-Downstate Medical Center, Brooklyn, NY 11203 (United States); Nakayama, Yasumi; Sequeira, Jeffrey M. [Department of Medicine, Cell Biology, SUNY-Downstate Medical Center, Brooklyn, NY 11203 (United States); Quadros, Edward V., E-mail: Edward.Quadros@downstate.edu [Department of Medicine, Cell Biology, SUNY-Downstate Medical Center, Brooklyn, NY 11203 (United States); School of Graduate Studies, SUNY-Downstate Medical Center, Brooklyn, NY 11203 (United States)

    2011-07-01

    The clinical phenotype of cobalamin (Cbl) deficiency is dictated by the essential role of this vitamin in two key enzymatic reactions. Multiple proteins and receptors participate in the absorption, transport and delivery of this vitamin to tissue cells. Cellular uptake of Cbl is mediated by transcobalamin (TC), a plasma protein and a transmembrane receptor (TCblR) with high affinity for TC saturated with Cbl. Knockdown of TCblR with siRNA results in decreased TC-Cbl uptake. The ensuing Cbl deficiency leads to an increase in doubling time and decreased proliferation of these cells. The study confirms the seminal role of this receptor in the cellular uptake of Cbl and its down-regulation as a potential strategy to inhibit proliferation of cancer cells.

  14. Peroxisome proliferator-activated receptorα agonists differentially regulate inhibitor of DNA binding expression in rodents and human cells.

    Science.gov (United States)

    González, María Del Carmen; Corton, J Christopher; Acero, Nuria; Muñoz-Mingarro, Dolores; Quirós, Yolanda; Alvarez-Millán, Juan José; Herrera, Emilio; Bocos, Carlos

    2012-01-01

    Inhibitor of DNA binding (Id2) is a helix-loop-helix (HLH) transcription factor that participates in cell differentiation and proliferation. Id2 has been linked to the development of cardiovascular diseases since thiazolidinediones, antidiabetic agents and peroxisome proliferator-activated receptor (PPAR) gamma agonists, have been reported to diminish Id2 expression in human cells. We hypothesized that PPARα activators may also alter Id2 expression. Fenofibrate diminished hepatic Id2 expression in both late pregnant and unmated rats. In 24 hour fasted rats, Id2 expression was decreased under conditions known to activate PPARα. In order to determine whether the fibrate effects were mediated by PPARα, wild-type mice and PPARα-null mice were treated with Wy-14,643 (WY). WY reduced Id2 expression in wild-type mice without an effect in PPARα-null mice. In contrast, fenofibrate induced Id2 expression after 24 hours of treatment in human hepatocarcinoma cells (HepG2). MK-886, a PPARα antagonist, did not block fenofibrate-induced activation of Id2 expression, suggesting a PPARα-independent effect was involved. These findings confirm that Id2 is a gene responsive to PPARα agonists. Like other genes (apolipoprotein A-I, apolipoprotein A-V), the opposite directional transcriptional effect in rodents and a human cell line further emphasizes that PPARα agonists have different effects in rodents and humans.

  15. SIRT1 inhibits proliferation of pancreatic cancer cells expressing pancreatic adenocarcinoma up-regulated factor (PAUF), a novel oncogene, by suppression of {beta}-catenin

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Il-Rae [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Koh, Sang Seok [Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333 (Korea, Republic of); Department of Functional Genomics, University of Science and Technology, Daejeon 305-333 (Korea, Republic of); Malilas, Waraporn; Srisuttee, Ratakorn; Moon, Jeong [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Choi, Young-Whan [Department of Horticultural Bioscience, Pusan National University, Miryang 627-706 (Korea, Republic of); Horio, Yoshiyuki [Department of Pharmacology, Sapporo Medical University, Sapporo 060-8556 (Japan); Oh, Sangtaek [Department of Advanced Fermentation Fusion Science and Technology, Kookmin University, Seoul 136-702 (Korea, Republic of); Chung, Young-Hwa, E-mail: younghc@pusan.ac.kr [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer SIRT1 inhibits protein levels of {beta}-catenin and its transcriptional activity. Black-Right-Pointing-Pointer Nuclear localization of SIRT1 is not required for the decrease of {beta}-catenin expression. Black-Right-Pointing-Pointer SIRT1-mediated degradation of {beta}-catenin is not required for GSK-3{beta} and Siah-1 but for proteosome. Black-Right-Pointing-Pointer SIRT1 activation inhibits proliferation of pancreatic cancer cells expressing PAUF. -- Abstract: Because we found in a recent study that pancreatic adenocarcinoma up-regulated factor (PAUF), a novel oncogene, induces a rapid proliferation of pancreatic cells by up-regulation of {beta}-catenin, we postulated that {beta}-catenin might be a target molecule for pancreatic cancer treatment. We thus speculated whether SIRT1, known to target {beta}-catenin in a colon cancer model, suppresses {beta}-catenin in those pancreatic cancer cells that express PAUF (Panc-PAUF). We further evaluated whether such suppression would lead to inhibition of the proliferation of these cells. The ectopic expression of either SIRT1 or resveratrol (an activator of SIRT1) suppressed levels of {beta}-catenin protein and its transcriptional activity in Panc-PAUF cells. Conversely, suppression of SIRT1 expression by siRNA enhanced {beta}-catenin expression and transcriptional activity. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for reduction of {beta}-catenin. Treatment with MG132, a proteasomal inhibitor, restored {beta}-catenin protein levels, suggesting that SIRT1-mediated degradation of {beta}-catenin requires proteasomal activity. It was reported that inhibition of GSK-3{beta} or Siah-1 stabilizes {beta}-catenin in colon cancer cells, but suppression of GSK-3{beta} or Siah-1 using siRNA in the presence of resveratrol instead diminished {beta}-catenin protein levels in Panc-PAUF cells. This suggests that GSK-3{beta} and Siah-1 are not involved in SIRT1

  16. SIRT1 inhibits proliferation of pancreatic cancer cells expressing pancreatic adenocarcinoma up-regulated factor (PAUF), a novel oncogene, by suppression of β-catenin

    International Nuclear Information System (INIS)

    Highlights: ► SIRT1 inhibits protein levels of β-catenin and its transcriptional activity. ► Nuclear localization of SIRT1 is not required for the decrease of β-catenin expression. ► SIRT1-mediated degradation of β-catenin is not required for GSK-3β and Siah-1 but for proteosome. ► SIRT1 activation inhibits proliferation of pancreatic cancer cells expressing PAUF. -- Abstract: Because we found in a recent study that pancreatic adenocarcinoma up-regulated factor (PAUF), a novel oncogene, induces a rapid proliferation of pancreatic cells by up-regulation of β-catenin, we postulated that β-catenin might be a target molecule for pancreatic cancer treatment. We thus speculated whether SIRT1, known to target β-catenin in a colon cancer model, suppresses β-catenin in those pancreatic cancer cells that express PAUF (Panc-PAUF). We further evaluated whether such suppression would lead to inhibition of the proliferation of these cells. The ectopic expression of either SIRT1 or resveratrol (an activator of SIRT1) suppressed levels of β-catenin protein and its transcriptional activity in Panc-PAUF cells. Conversely, suppression of SIRT1 expression by siRNA enhanced β-catenin expression and transcriptional activity. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for reduction of β-catenin. Treatment with MG132, a proteasomal inhibitor, restored β-catenin protein levels, suggesting that SIRT1-mediated degradation of β-catenin requires proteasomal activity. It was reported that inhibition of GSK-3β or Siah-1 stabilizes β-catenin in colon cancer cells, but suppression of GSK-3β or Siah-1 using siRNA in the presence of resveratrol instead diminished β-catenin protein levels in Panc-PAUF cells. This suggests that GSK-3β and Siah-1 are not involved in SIRT1-mediated degradation of β-catenin in the cells. Finally, activation of SIRT1 inhibited the proliferation of Panc-PAUF cells by down-regulation of cyclin-D1, a target

  17. Leucyl-tRNA Synthetase Regulates Lactation and Cell Proliferation via mTOR Signaling in Dairy Cow Mammary Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Lina Wang

    2014-04-01

    Full Text Available The role of LeuRS, an aminoacyl-tRNA synthetase, as an intracellular l-leucine sensor for the mTORC1 pathway has been the subject of much research recently. Despite this, the association between LeuRS and lactation in dairy cow mammary epithelial cells (DCMECs remains unknown. In this study, we found that LeuRS expression in mammary gland tissue was significantly higher during lactation than pregnancy. Moreover, our data demonstrates that LeuRS is localized in the cytoplasm. Treatment with leucine increased DCMECs viability and proliferation, as well as mammalian target of rapamycin (mTOR, p-mTOR, ribosomal protein S6 kinase 1 (S6K1, p-S6K1, β-Casein, sterol regulatory element binding protein 1c (SREBP-1c, glucose transporter 1 (GLUT1, and Cyclin D1 mRNA and protein expression. Secretion of lactose and triglyceride were also increased. siRNA-mediated knockdown of LeuRS led to reduction in all of these processes. Based on these data, LeuRS up-regulates the mTOR pathway to promote proliferation and lactation of DCMECs in response to changes in the intracellular leucine concentration.

  18. Mir-23a and mir-125b regulate neural stem/progenitor cell proliferation by targeting Musashi1.

    Science.gov (United States)

    Gioia, Ubaldo; Di Carlo, Valerio; Caramanica, Pasquale; Toselli, Camilla; Cinquino, Antonella; Marchioni, Marcella; Laneve, Pietro; Biagioni, Stefano; Bozzoni, Irene; Cacci, Emanuele; Caffarelli, Elisa

    2014-01-01

    Musashi1 is an RNA binding protein that controls the neural cell fate, being involved in maintaining neural progenitors in their proliferative state. In particular, its downregulation is needed for triggering early neural differentiation programs. In this study, we profiled microRNA expression during the transition from neural progenitors to differentiated astrocytes and underscored 2 upregulated microRNAs, miR-23a and miR-125b, that sinergically act to restrain Musashi1 expression, thus creating a regulatory module controlling neural progenitor proliferation. PMID:25483045

  19. Ubiquitin carboxyl terminal hydrolase L1 negatively regulates TNF{alpha}-mediated vascular smooth muscle cell proliferation via suppressing ERK activation

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, Tomonaga; Li, Jinqing; Dong, Xiaoyu; Potts, Jay D. [Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Tang, Dong-Qi [Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL 32610-0275 (United States); Li, Dong-Sheng, E-mail: dsli@yymc.edu.cn [Hubei Key Laboratory of Embryonic Stem Cell Research, Tai He Hospital, Yunyang Medical College, 32 S. Renmin Rd., Shiyan, Hubei 442000 (China); Cui, Taixing, E-mail: taixing.cui@uscmed.sc.edu [Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States)

    2010-01-01

    Deubiquitinating enzymes (DUBs) appear to be critical regulators of a multitude of processes such as proliferation, apoptosis, differentiation, and inflammation. We have recently demonstrated that a DUB of ubiquitin carboxyl terminal hydrolase L1 (UCH-L1) inhibits vascular lesion formation via suppressing inflammatory responses in vasculature. However, the precise underlying mechanism remains to be defined. Herein, we report that a posttranscriptional up-regulation of UCH-L1 provides a negative feedback to tumor necrosis factor alpha (TNF{alpha})-mediated activation of extracellular signal-regulated kinases (ERK) and proliferation in vascular smooth muscle cells (VSMCs). In rat adult VSMCs, adenoviral over-expression of UCH-L1 inhibited TNF{alpha}-induced activation of ERK and DNA synthesis. In contrast, over-expression of UCH-L1 did not affect platelet derived growth factor (PDGF)-induced VSMC proliferation and activation of growth stimulating cascades including ERK. TNF{alpha} hardly altered UCH-L1 mRNA expression and stability; however, up-regulated UCH-L1 protein expression via increasing UCH-L1 translation. These results uncover a novel mechanism by which UCH-L1 suppresses vascular inflammation.

  20. Curcumin, a potent anti-tumor reagent, is a novel histone deacetylase inhibitor regulating B-NHL cell line Raji proliferation

    Institute of Scientific and Technical Information of China (English)

    Hong-li LIU; Yan CHEN; Guo-hui CUI; Jian-feng ZHOU

    2005-01-01

    Aim: To investigate curcumin (diferuloylmethane) induced apoptosis and its molecular mechanism of action in B-NHL cell line Raji cells. Methods: Raji cells were cultured in RPMI- 1640 medium and treated with curcumin in different concentrations. 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium (MTT) assay was used to detect growth inhibition and Hoechst 33258 staining was used to detect apoptosis. Immunocytochemistry and Western blot were used to detect the expressions of histone deacetylase 1, 3, and 8 (HDAC 1, HDAC3, and HDAC8) and acetylated histone H4 (Ac-histone H4) protein. Results: Curcumin inhibited the proliferation of B-NHL cell line Raji cells with a 36-h IC50 value of 24.1±2.0 μmol/L.Hoechst 33258 staining showed that curcumin could induce Raji cell apoptosis.The expression levels of HDAC 1, HDAC3, and HDAC8 proteins were downregulated following curcumin treatment in Raji cells, whereas Ac-histone H4 protein expression was upregulated after treatment with curcumin. Conclusion: Curcumin, as a new member of the histone deacetylase inhibitors, can inhibit the expression of class I HDACs (HDAC1, HDAC3, and HDAC8), and can increase the expression of Ac-histone H4 in Raji cells. Curcumin plays an important role in regulating B-NHL cell line Raji cell proliferation and apoptosis.

  1. Quantification of uncoupling protein 2 reveals its main expression in immune cells and selective up-regulation during T-cell proliferation.

    Directory of Open Access Journals (Sweden)

    Anne Rupprecht

    Full Text Available Uncoupling protein 2 (UCP2 is an inner mitochondrial membrane protein. Although the protein was discovered in 1997, its function and even its tissue distribution are still under debate. Here we present a quantitative analysis of mRNA and protein expression in various mice tissues, revealing that UCP2 is mainly expressed in organs and cells associated with the immune system. Although the UCP2 gene is present in the brain, as demonstrated using quantitative RT-PCR, the protein was not detectable in neurons under physiological conditions. Instead, we could detect UCP2 in microglia, which act in the immune defense of the central nervous system. In lymphocytes, activation led to a ten-fold increase of UCP2 protein expression simultaneously to the increase in levels of other mitochondrial proteins, whereas lymphocyte re-stimulation resulted in the selective increase of UCP2. The highest detected level of UCP2 expression in stimulated T-cells (0.54 ng/(µg total cellular protein was approximately 200 times lower than the level of UCP1 in brown adipose tissue from room temperature acclimated mice. Both the UCP2 expression pattern and the time course of up-regulation in stimulated T-cells imply UCP2's involvement in the immune response, probably by controlling the metabolism during cell proliferation.

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

    OpenAIRE

    Cheng-Rong Yu; Dambuza, Ivy M.; Yong-Jun Lee; Frank, Gregory M.; Egwuagu, Charles E.

    2013-01-01

    STAT3 regulates CD4+ T cell survival and differentiation. However, its effects on CD8+ T cells are not well understood. Here, we show that in comparison to WT CD8+ T cells, STAT3-deficient CD8+ T cells exhibit a preactivated memory-like phenotype, produce more IL-2, proliferate faster, and are more sensitive to activation-induced cell death (AICD). The enhanced proliferation and sensitivity to AICD correlated with downregulation of class-O forkhead transcription factors (FoxO1, FoxO3A), p21wa...

  3. Epigenetic regulation of proliferation and invasion in hepatocellular carcinoma cells by CBP/p300 histone acetyltransferase activity.

    Science.gov (United States)

    Inagaki, Yuji; Shiraki, Katsuya; Sugimoto, Kazushi; Yada, Takazumi; Tameda, Masahiko; Ogura, Suguru; Yamamoto, Norihiko; Takei, Yoshiyuki; Ito, Masaaki

    2016-02-01

    Altered epigenetic control of gene expression plays a substantial role in tumor development and progression. Accumulating studies suggest that somatic mutations of CREB binding proteins (CBP)/p300 occur in some cancer cells. CBP/p300 possess histone acetyltransferase (HAT) activity, and are involved in many cellular processes. In this study, we investigated the expression and functional role of CBP/p300 in hepatocellular carcinoma (HCC) using the specific inhibitor C646 of CBP/p300 HAT activity. We examined its effect on several apoptosis-related proteins and invasion-related genes. The results showed that CBP/p300 were highly expressed in HCC tissues and that expression of p300, but not of CBP, was strongly correlated with the malignant character of HCC. C646 inhibited proliferation of HCC cell lines in a dose dependent manner. C646 significantly augmented TRAIL-induced apoptotic sensitivity, which was accompanied by reduced levels of survivin, in HepG2, HLE and SK-HEP1 cells. C646 significantly inhibited invasion of Huh7, HLE and SK-HEP1 cells. The level of matrix metallopeptidase 15 (MMP15) mRNA expression was significantly reduced, whereas the level of laminin alpha 3 (LAMA3) and secreted phosphoprotein 1 (SPP1) mRNA expression was significantly increased in Huh7 cells following exposure to C646. In conclusion, our results suggest that CBP/p300 HAT activity has an important role in malignant transformation, proliferation, apoptotic sensitivity and invasion in HCC. CBP/p300 could be a promising therapeutic target in HCC. PMID:26676548

  4. miR-206 is down-regulated in breast cancer and inhibits cell proliferation through the up-regulation of cyclinD2

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Jing, E-mail: zhougjing9888@163.com [Department of Oncology, Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu (China); Tian, Ye, E-mail: tianye2010077@163.com [Department of Hepatobiliary Surgery, Affiliated Yijishan Hospital of Wannan Medical College, Wuhu, Anhui (China); Li, Juan, E-mail: 402310848@163.com [Department of Oncology, Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu (China); Lu, Binbin, E-mail: lubin1976@163.com [Department of Oncology, Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu (China); Sun, Ming, E-mail: 422825636@qq.com [Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu (China); Zou, Yanfen, E-mail: 569111165@qq.com [Department of Obstetrics and Gynaecology, Jiangsu Province Hospital, Nanjing, Jiangsu (China); Kong, Rong, E-mail: 31815857@qq.com [Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu (China); Luo, Yanhong, E-mail: 252376737@qq.com [School of Pharmacy, Nanjing Medical University, Nanjing, Jiangsu (China); Shi, Yongguo, E-mail: 12071018@qq.com [Department of Oncology, Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu (China); Wang, Keming, E-mail: Tianyr1@163.com [Department of Oncology, Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu (China); Ji, Guozhong, E-mail: 252376737@qq.com [Department of Oncology, Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu (China)

    2013-04-05

    Highlights: ► miR-206 was downexpressed in tumor samples compared with matched normal samples. ► Enhanced expression of miR-206 could inhibit breast cancer growth in vitro. ► Luciferase confirmed miR-206 functions as an anti-oncogene by targeting cyclinD2. ► A reverse correlation between miR-206 and cyclinD2 in breast cancer was found. -- Abstract: MicroRNAs act as important gene regulators in human genomes, and their aberrant expression is linked to many malignancies. Aberrant expression of miR-206 has been frequently reported in cancer studies; however, the role and mechanism of its function in breast cancer remains unclear. Quantitative real-time PCR was performed to detect the relative expression levels of miR-206 in breast cancer and normal breast tissues. Lower expression of miR-206 in breast cancer tissues was associated with larger tumour size and a more advanced clinical stage. Further in vitro observations showed that the enforced expression of miR-206 in MCF-7 breast cancer cells inhibited cell growth by blocking the G1/S transition and suppressed cell proliferation and colony formation, implying that miR-206 functions as a tumour suppressor in the progression of breast cancer. Interestingly, Luciferase assays first revealed that miR-206 inhibited cyclinD2 expression by targeting two binding sites in the 3′-untranslated region of cyclinD2 mRNA. qRT-PCR and Western blot assays verified that miR-206 reduced cyclinD2 expression at both the mRNA and protein levels. A reverse correlation between miR-206 and cyclinD2 expression was noted in breast cancer tissues. Altogether, our results identify a crucial tumour suppressive role of miR-206 in the progression of breast cancer, at least partly via up-regulation of the expression of cyclinD2, and suggest that miR-206 might be a candidate prognostic predictor or an anticancer therapeutic target for breast cancer patients.

  5. Identification of miR-2400 gene as a novel regulator in skeletal muscle satellite cells proliferation by targeting MYOG gene

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei Wei [The Laboratory of Cell and Development, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China); College of Life Sciences and Agriculture & Forestry, Qiqihar University, Qiqihar, Heilongjiang 161006 (China); Tong, Hui Li; Sun, Xiao Feng; Hu, Qian; Yang, Yu; Li, Shu Feng [The Laboratory of Cell and Development, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China); Yan, Yun Qin, E-mail: yanyunqin@sohu.com [The Laboratory of Cell and Development, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China); Li, Guang Peng [The Key Laboratory of Mammal Reproductive Biology and Biotechnology Ministry of Education, Inner Mongolia University, Hohhot 010021 (China)

    2015-08-07

    MicroRNAs play critical roles in skeletal muscle development as well as in regulation of muscle cell proliferation and differentiation. Previous study in our laboratory showed that the expression level of miR-2400, a novel and unique miRNA from bovine, had significantly changed in skeletal muscle-derived satellite cells (MDSCs) during differentiation, however, the function and expression pattern for miR-2400 in MDSCs has not been fully understood. In this report, we firstly identified that the expression levels of miR-2400 were down-regulated during MDSCs differentiation by stem-loop RT-PCR. Over-expression and inhibition studies demonstrated that miR-2400 promoted MDSCs proliferation by EdU (5-ethynyl-2′ deoxyuridine) incorporation assay and immunofluorescence staining of Proliferating cell nuclear antigen (PCNA). Luciferase reporter assays showed that miR-2400 directly targeted the 3′ untranslated regions (UTRs) of myogenin (MYOG) mRNA. These data suggested that miR-2400 could promote MDSCs proliferation through targeting MYOG. Furthermore, we found that miR-2400, which was located within the eighth intron of the Wolf-Hirschhorn syndrome candidate 1-like 1 (WHSC1L1) gene, was down-regulated in MDSCs in a direct correlation with the WHSC1L1 transcript by Clustered regularly interspaced palindromic repeats interference (CRISPRi). In addition, these observations not only provided supporting evidence for the codependent expression of intronic miRNAs and their host genes in vitro, but also gave insight into the role of miR-2400 in MDSCs proliferation. - Highlights: • miR-2400 is a novel and unique miRNA from bovine. • miR-2400 could promote skeletal muscle satellite cells proliferation. • miR-2400 directly targeted the 3′ untranslated regions of MYOG mRNA. • miR-2400 could be coexpressed together with its host gene WHSC1L1.

  6. Identification of miR-2400 gene as a novel regulator in skeletal muscle satellite cells proliferation by targeting MYOG gene

    International Nuclear Information System (INIS)

    MicroRNAs play critical roles in skeletal muscle development as well as in regulation of muscle cell proliferation and differentiation. Previous study in our laboratory showed that the expression level of miR-2400, a novel and unique miRNA from bovine, had significantly changed in skeletal muscle-derived satellite cells (MDSCs) during differentiation, however, the function and expression pattern for miR-2400 in MDSCs has not been fully understood. In this report, we firstly identified that the expression levels of miR-2400 were down-regulated during MDSCs differentiation by stem-loop RT-PCR. Over-expression and inhibition studies demonstrated that miR-2400 promoted MDSCs proliferation by EdU (5-ethynyl-2′ deoxyuridine) incorporation assay and immunofluorescence staining of Proliferating cell nuclear antigen (PCNA). Luciferase reporter assays showed that miR-2400 directly targeted the 3′ untranslated regions (UTRs) of myogenin (MYOG) mRNA. These data suggested that miR-2400 could promote MDSCs proliferation through targeting MYOG. Furthermore, we found that miR-2400, which was located within the eighth intron of the Wolf-Hirschhorn syndrome candidate 1-like 1 (WHSC1L1) gene, was down-regulated in MDSCs in a direct correlation with the WHSC1L1 transcript by Clustered regularly interspaced palindromic repeats interference (CRISPRi). In addition, these observations not only provided supporting evidence for the codependent expression of intronic miRNAs and their host genes in vitro, but also gave insight into the role of miR-2400 in MDSCs proliferation. - Highlights: • miR-2400 is a novel and unique miRNA from bovine. • miR-2400 could promote skeletal muscle satellite cells proliferation. • miR-2400 directly targeted the 3′ untranslated regions of MYOG mRNA. • miR-2400 could be coexpressed together with its host gene WHSC1L1

  7. Centrosomal Protein of 55 Regulates Glucose Metabolism, Proliferation and Apoptosis of Glioma Cells via the Akt/mTOR Signaling Pathway

    Science.gov (United States)

    Wang, Guangzhi; Liu, Mingna; Wang, Hongjun; Yu, Shan; Jiang, Zhenfeng; Sun, Jiahang; Han, Ke; Shen, Jia; Zhu, Minwei; Lin, Zhiguo; Jiang, Chuanlu; Guo, Mian

    2016-01-01

    Introduction: Glioma is one of the most common and most aggressive brain tumors in humans. The molecular and cellular mechanisms responsible for the onset and the progression of glioma are elusive and controversial. Centrosomal protein of 55 (CEP55) was initially described as a highly coiled-coil protein that plays critical roles in cell division, but was recently identified as being overexpressed in many human cancers. The function of CEP55 has not previously been characterized in glioma. We aim to discover the effect and mechanism of CEP55 in glioma development. Method: qRT-PCR and immunohistochemistry were used to analyze CEP55 expression. Glucose uptake, western blot, MTS, CCK-8, Caspase-3 activity and TUNEL staining assays were performed to investigate the role and mechanism of CEP55 on glioma cell process. Results: We found that the levels of CEP55 expression were upregulated in glioma. In addition, CEP55 appeared to regulate glucose metabolism of glioma cells. Furthermore, knockdown of CEP55 inhibited cell proliferation and induced cell apoptosis in glioma. Finally, we provided preliminary evidence that knockdown of CEP55 inhibited glioma development via suppressing the activity of Akt/mTOR signaling. Conclusions: Our results demonstrated that CEP55 regulates glucose metabolism, proliferation and apoptosis of glioma cells via the Akt/mTOR signaling pathway, and its promotive effect on glioma tumorigenesis can be a potential target for glioma therapy in the future. PMID:27471559

  8. Cyclin-dependent kinase 5 regulates the proliferation, motility and invasiveness of lung cancer cells through its effects on cytoskeletal remodeling.

    Science.gov (United States)

    Liu, Jun-Li; Gu, Run-Xia; Zhou, Xiao-Shu; Zhou, Fang-Zheng; Wu, Gang

    2015-09-01

    Determining the molecular phenotype is a key to understanding and predicting the metastatic potential and the prognosis for patients with lung cancer. Our previous study demonstrated that increased expression of cyclin‑dependent kinase 5 (CDK5) in patients with non‑small cell lung cancer (NSCLC) is associated with a poorer prognosis. The present study aimed to further investigate the underlying mechanism of CDK5 in vitro and in vivo using the A549 human NSCLC cell line. A 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide assay was used to quantify the proliferation of the A549 cells; migration assay and invasiveness assays were performed using Transwell chambers and wound healing assays were used to assess cell motility, which was assessed by measuring the movement of cells. Inhibition of CDK5 by roscovitine and small interfering (si)RNA was used to investigate the mechanism of CDK5 in the process of A549 lung cancer cell proliferation, migration and invasion. The results demonstrated that functional inhibition of CDK5 using roscovitine and siRNA markedly suppressed the proliferation of A549 cells and resulted in a reduced tumor mass in vivo. In addition, the hinhibition of CDK5 reduced the migration and invasiveness of the A549 cells in vitro and in vivo. Notably, CDK5 inhibition also impaired tumor cell cytoskeletal remodeling and led to loss of cell polarity, which may partially explain the reduction of A549 cell mobility and invasiveness. The results of the present study revealed that CDK5 may be important in the regulation of migration and invasiveness in NSCLC through its effects on cytoskeletal remodeling. PMID:26018459

  9. The C-terminal pentapeptide of Nanog tryptophan repeat domain interacts with Nac1 and regulates stem cell proliferation but not pluripotency.

    Science.gov (United States)

    Ma, Tianhua; Wang, Zhe; Guo, Yunqian; Pei, Duanqing

    2009-06-12

    Overexpression of Nanog in mouse embryonic stem (ES) cells has been shown to abrogate the requirement of leukemia inhibitory factor for self-renewal in culture. Little is known about the molecular mechanism of Nanog function. Here we describe the role of the tryptophan repeat (WR) domain, one of the two transactivators at its C terminus, in regulating stem cell proliferation as well as pluripotency. We first created a supertransactivator, W2W3x10, by duplicating repeats W2W3 10 times and discovered that it can functionally substitute for wild type WR at sustaining pluripotency, albeit with a significantly slower cell cycle, phenocopying Nanog(9W) with the C-terminal pentapeptide (WNAAP) of WR deleted. ES cells carrying both W2W3x10 and Nanog(9W) have a longer G1 phase, a shorter S phase in cell cycle distribution and progression analysis, and a lower level of pAkt(Ser473) compared with wild type Nanog, suggesting that both mutants impact the cell cycle machinery via the phosphatidylinositol 3-kinase/Akt pathway. Both mutants remain competent in dimerizing with Nanog but cannot form a complex with Nac1 efficiently, suggesting that WNAAP may be involved in Nac1 binding. By tagging Gal4DBD with WNAAP, we demonstrated that this pentapeptide is sufficient to confer Nac1 binding. Furthermore, we can rescue W2W3x10 by placing WNAAP at the corresponding locations. Finally, we found that Nanog and Nac1 synergistically up-regulate ERas expression and promote the proliferation of ES cells. These results suggest that Nanog interacts with Nac1 through WNAAP to regulate the cell cycle of ES cells via the ERas/phosphatidylinositol 3-kinase/Akt pathway, but not pluripotency, thus decoupling cell cycle control from pluripotency.

  10. Regulation of store-operated and voltage-operated Ca2+ channels in the proliferation and death of oligodendrocyte precursor cells by golli proteins

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    Pablo M Paez

    2009-04-01

    Full Text Available OPCs (oligodendrocyte precursor cells) express golli proteins which, through regulation of Ca2+ influx, appear to be important in OPC process extension/retraction and migration. The aim of the present study was to examine further the role of golli in regulating OPC development. The effects of golli ablation and overexpression were examined in primary cultures of OPCs prepared from golli-KO (knockout) and JOE (golli J37-overexpressing) mice. In OPCs lacking golli, or overexpressing golli, differentiation induced by growth factor withdrawal was impaired. Proliferation analysis in the presence of PDGF (platelet-derived growth factor), revealed that golli enhanced the mitogen-stimulated proliferation of OPCs through activation of SOCCs (store-operated Ca2+ channels). PDGF treatment induced a biphasic increase in OPC intracellular Ca2+, and golli specifically increased Ca2+ influx during the second SOCC-dependent phase that followed the initial release of Ca2+ from intracellular stores. This store-operated Ca2+ uptake appeared to be essential for cell division, since specific SOCC antagonists completely blocked the effects of PDGF and golli on OPC proliferation. Additionally, in OPCs overexpressing golli, increased cell death was observed after mitogen withdrawal. This phenomenon could be prevented by exposure to VOCC (voltage-operated Ca2+ channel) blockers, indicating that the effect of golli on cell death involved increased Ca2+ influx through VOCCs. The results showed a clear effect of golli on OPC development and support a role for golli in modulating multiple Ca2+-regulatory events through VOCCs and SOCCs. Our results also suggest that PDGF engagement of its receptor resulting in OPC proliferation proceeds through activation of SOCCs.

  11. Post-transcriptional regulation of cyclins D1, D3 and G1 and proliferation of human cancer cells depend on IMP-3 nuclear localization.

    Science.gov (United States)

    Rivera Vargas, T; Boudoukha, S; Simon, A; Souidi, M; Cuvellier, S; Pinna, G; Polesskaya, A

    2014-05-29

    RNA-binding proteins of the IMP family (insulin-like growth factor 2 (IGF2) mRNA-binding proteins 1-3) are important post-transcriptional regulators of gene expression. Multiple studies have linked high expression of IMP proteins, and especially of IMP-3, to an unfavorable prognosis in numerous types of cancer. The specific importance of IMP-3 for cancer transformation remains poorly understood. We here show that all three IMPs can directly bind the mRNAs of cyclins D1, D3 and G1 (CCND1, D3 and G1) in vivo and in vitro, and yet only IMP-3 regulates the expression of these cyclins in a significant manner in six human cancer cell lines of different origins. In the absence of IMP-3, the levels of CCND1, D3 and G1 proteins fall dramatically, and the cells accumulate in the G1 phase of the cell cycle, leading to almost complete proliferation arrest. Our results show that, compared with IMP-1 and IMP-2, IMP-3 is enriched in the nucleus, where it binds the transcripts of CCND1, D3 and G1. The nuclear localization of IMP-3 depends on its protein partner HNRNPM and is indispensable for the post-transcriptional regulation of expression of the cyclins. Cytoplasmic retention of IMP-3 and HNRNPM in human cancer cells leads to significant drop in proliferation. In conclusion, a nuclear IMP-3-HNRNPM complex is important for the efficient synthesis of CCND1, D3 and G1 and for the proliferation of human cancer cells.

  12. Ras-activated RSK1 phosphorylates EBP50 to regulate its nuclear localization and promote cell proliferation.

    Science.gov (United States)

    Lim, Hooi Cheng; Jou, Tzuu-Shuh

    2016-03-01

    Differential subcellular localization of EBP50 leads to its controversial role in cancer biology either as a tumor suppressor when it resides at the membrane periphery, or a tumor facilitator at the nucleus. However, the mechanism behind nuclear localization of EBP50 remains unclear. A RNA interference screening identified the downstream effector of the Ras-ERK cascade, RSK1, as the molecule unique for nuclear transport of EBP50. RSK1 binds to EBP50 and phosphorylates it at a conserved threonine residue at position 156 (T156) under the regulation of growth factor. Mutagenesis experiments confirmed the significance of T156 residue in nuclear localization of EBP50, cellular proliferation, and oncogenic transformation. Our study sheds light on a possible therapeutic strategy targeting at this aberrant nuclear expression of EBP50 without affecting the normal physiological function of EBP50 at other subcellular localization.

  13. Up-regulation of Hsp27 by ERα/Sp1 facilitates proliferation and confers resistance to apoptosis in human papillary thyroid cancer cells.

    Science.gov (United States)

    Mo, Xiao-Mei; Li, Li; Zhu, Ping; Dai, Yu-Jie; Zhao, Ting-Ting; Liao, Ling-Yao; Chen, George G; Liu, Zhi-Min

    2016-08-15

    17β-estradiol (E2) has been suggested to play a role in the development and progression of papillary thyroid cancer. Heat shock protein 27 (Hsp27) is a member of the Hsp family that is responsible for cell survival under stressful conditions. Previous studies have shown that the 5'-promoter region of Hsp27 gene contains a specificity protein-1 (Spl) and estrogen response element half-site (ERE-half), which contributes to Hsp27 induction by E2 in breast cancer cells. However, it is unclear whether Hsp27 can be up-regulated by E2 and which estrogen receptor (ER) isoform and tethered transcription factor are involved in this regulation in papillary thyroid cancer cells. In the present study, we demonstrated that Hsp27 can be effectively up-regulated by E2 at mRNA and protein levels in human K1 and BCPAP papillary thyroid cancer cells which have more than two times higher level of ERα than that of ERβ. The up-regulation of Hsp27 by E2 is mediated by ERα/Sp1 and ERβ has repressive effect on this ERα/Sp1-mediated up-regulation of Hsp27. Moreover, we showed that the up-regulation of Hsp27 by ERα/Sp1 facilitates proliferation and confers resistance to apoptosis through interaction with procaspase-3. Targeting this pathway may be a potential strategy for therapy of papillary thyroid cancer. PMID:27179757

  14. Protein tyrosine phosphatase µ (PTP µ or PTPRM, a negative regulator of proliferation and invasion of breast cancer cells, is associated with disease prognosis.

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    Ping-Hui Sun

    Full Text Available BACKGROUND: PTPRM has been shown to exhibit homophilic binding and confer cell-cell adhesion in cells including epithelial and cancer cells. The present study investigated the expression of PTPRM in breast cancer and the biological impact of PTPRM on breast cancer cells. DESIGN: Expression of PTPRM protein and gene transcript was examined in a cohort of breast cancer patients. Knockdown of PTPRM in breast cancer cells was performed using a specific anti-PTPRM transgene. The impact of PTPRM knockdown on breast cancer was evaluated using in vitro cell models. RESULTS: A significant decrease of PTPRM transcripts was seen in poorly differentiated and moderately differentiated tumours compared with well differentiated tumours. Patients with lower expression of PTPRM had shorter survival compared with those which had a higher level of PTPRM expression. Knockdown of PTPRM increased proliferation, adhesion, invasion and migration of breast cancer cells. Furthermore, knockdown of PTPRM in MDA-MB-231 cells resulted in increased cell migration and invasion via regulation of the tyrosine phosphorylation of ERK and JNK. CONCLUSIONS: Decreased expression of PTPRM in breast cancer is correlated with poor prognosis and inversely correlated with disease free survival. PTPRM coordinated cell migration and invasion through the regulation of tyrosine phosphorylation of ERK and JNK.

  15. Regulation of cell proliferation of human induced pluripotent stem cell-derived mesenchymal stem cells via ether-à-go-go 1 (hEAG1) potassium channel.

    Science.gov (United States)

    Zhang, Jiao; Chan, Yau-Chi; Ho, Jenny Chung-Yee; Siu, Chung-Wah; Lian, Qizhou; Tse, Hung-Fat

    2012-07-15

    The successful generation of a high yield of mesenchymal stem cells (MSCs) from human induced pluripotent stem cells (iPSCs) may represent an unlimited cell source with superior therapeutic benefits for tissue regeneration to bone marrow (BM)-derived MSCs. We investigated whether the differential expression of ion channels in iPSC-MSCs was responsible for their higher proliferation capacity than BM-MSCs. The expression of ion channels for K(+), Na(+), Ca(2+), and Cl(-) was examined by RT-PCR. The electrophysiological properties of iPSC-MSCs and BM-MSCs were then compared by patch-clamp experiments to verify their functional roles. Significant mRNA expression of ion channel genes including KCa1.1, KCa3.1, KCNH1, Kir2.1, SCN9A, CACNA1C, and Clcn3 was observed in both human iPSC-MSCs and BM-MSCs, whereas Kir2.2 and Kir2.3 were only detected in human iPSC-MSCs. Five types of currents [big-conductance Ca(2+)-activated K(+) current (BK(Ca)), delayed rectifier K(+) current (IK(DR)), inwardly rectifying K(+) current (I(Kir)), Ca(2+)-activated K(+) current (IK(Ca)), and chloride current (I(Cl))] were found in iPSC-MSCs (83%, 47%, 11%, 5%, and 4%, respectively) but only four of them (BK(Ca), IK(DR), I(Kir), and IK(Ca)) were identified in BM-MSCs (76%, 25%, 22%, and 11%, respectively). Cell proliferation was examined with MTT or bromodeoxyuridine assay, and doubling times were 2.66 and 3.72 days for iPSC-MSCs and BM-MSCs, respectively, showing a 1.4-fold discrepancy. Blockade of IK(DR) with short hairpin RNA or human ether-à-go-go 1 (hEAG1) channel blockers, 4-AP and astemizole, significantly reduced the rate of proliferation of human iPSC-MSCs. These treatments also decreased the rate of proliferation of human BM-MSCs albeit to a lesser extent. These findings demonstrate that the hEAG1 channel plays a crucial role in controlling the proliferation rate of human iPSC-MSCs and to a lesser extent in BM-MSCs. PMID:22357737

  16. N-methylhemeanthidine chloride, a novel Amaryllidaceae alkaloid, inhibits pancreatic cancer cell proliferation via down-regulating AKT activation

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    Guo, Guoli; Yao, Guangmin; Zhan, Guanqun; Hu, Yufeng [Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei PR China (China); Yue, Ming [Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei (China); Cheng, Ling; Liu, Yaping; Ye, Qi [Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei PR China (China); Qing, Guoliang [Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei (China); Zhang, Yonghui, E-mail: zhangyh@mails.tjmu.edu.cn [Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei PR China (China); Liu, Hudan, E-mail: hudanliu@hust.edu.cn [Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei PR China (China)

    2014-11-01

    We previously reported the isolation of a novel Amaryllidaceae alkaloid, N-methylhemeanthidine chloride (NMHC), from Zephyranthes candida, which exhibits potent cytotoxicity in a spectrum of tumor cells. However, the mechanism of action remains unclear. Using multiple cell lines derived from human pancreatic cancer, one of the most mortal and refractory human malignancies, we further studied the NMHC-mediated cytotoxicity and found that it induced drastic cytotoxicity in pancreatic cancer cells whereas an insignificant effect on a noncancerous cell line. The NMHC-mediated growth inhibition was more severe than the first-line chemotherapeutic agent gemcitabine, leading to cell cycle arrest, apoptotic death and decreased glycolysis. NMHC exerted its function through down-regulating AKT activation, and the ectopic expression of activated AKT rescued the growth inhibition. Consistently, NMHC injections in a pancreatic cancer xenograft model manifested the anti-tumor effect in vivo. Engrafted tumor cells underwent AKT attenuation and apoptotic death upon treatments. As such, we here demonstrate the AKT inhibition may be one of the mechanisms by which NMHC decreases tumor cell survival rate in vitro and in vivo. Our data thereby suggest that NMHC holds great promise as a potent chemotherapeutic agent against pancreatic cancer and sheds new light on obtaining such agents from natural products toward therapeutic purposes. - Highlights: • N-methylhemeanthidine chloride (NMHC) is a novel Amaryllidaceae alkaloid. • NMHC exhibits potent anti-neoplastic activity. • NMHC leads to cell cycle arrest, apoptotic death and decreased metabolism. • NMHC down-regulates the AKT signaling pathway.

  17. Senegenin promotes in vitro proliferation of human neural progenitor cells

    Institute of Scientific and Technical Information of China (English)

    Fang Shi; Zhigang Liang; Zixuan Guo; Ran Li; Fen Yu; Zhanjun Zhang; Xuan Wang; Xiaomin Wang

    2011-01-01

    Senegenin, an effective component of Polygala tenuifolia root extract, promotes proliferation and differentiation of neural progenitor cells in the hippocampus.However, the effects of senegenin on mesencephalon-derived neural progenitor cells remain poorly understood.Cells from a ventral mesencephalon neural progenitor cell line (ReNcell VM) were utilized as models for pharmaceutical screening.The effects of various senegenin concentrations on cell proliferation were analyzed,demonstrating that high senegenin concentrations (5, 10, 50, and 100 pmo/L), particularly 50 pmol/L, significantly promoted proliferation of ReNcell VM cells.In the mitogen-activated protein kinase signal transduction pathway, senegenin significantly increased phosphorylation levels of extracellular signal-regulated kinases.Moreover, cell proliferation was suppressed by extracellular signal-regulated kinase inhibitors.Results suggested that senegenin contributed to in vitro proliferation of human neural progenitor cells by upregulating phosphorylation of extracellular signal-regulated kinase.

  18. Fatty acid binding protein 4 is a target of VEGF and a regulator of cell proliferation in endothelial cells

    OpenAIRE

    Elmasri, Harun; Karaaslan, Cagatay; Teper, Yaroslav; Ghelfi, Elisa; Weng, Meiqian; Ince, Tan A.; Kozakewich, Harry; Bischoff, Joyce; Cataltepe, Sule

    2009-01-01

    Fatty acid binding protein 4 (FABP4) plays an important role in maintaining glucose and lipid homeostasis. FABP4 has been primarily regarded as an adipocyte- and macrophage-specific protein, but recent studies suggest that it may be more widely expressed. We found strong FABP4 expression in the endothelial cells (ECs) of capillaries and small veins in several mouse and human tissues, including the heart and kidney. FABP4 was also detected in the ECs of mature human placental vessels and infan...

  19. p38 MAPK-Mediated Bmi-1 down-regulation and defective proliferation in ATM-deficient neural stem cells can be restored by Akt activation.

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    Jeesun Kim

    Full Text Available A-T (ataxia telangiectasia is a genetic disease caused by a mutation in the Atm (A-T mutated gene that leads to neurodegeneration. Despite an increase in the numbers of studies in this area in recent years, the mechanisms underlying neurodegeneration in human A-T are still poorly understood. Previous studies demonstrated that neural stem cells (NSCs isolated from the subventricular zone (SVZ of Atm(-/- mouse brains show defective self-renewal and proliferation, which is accompanied by activation of chronic p38 mitogen-activated protein kinase (MAPK and a lower level of the polycomb protein Bmi-1. However, the mechanism underlying Bmi-1 down-regulation and its relevance to defective proliferation in Atm(-/- NSCs remained unclear. Here, we show that over-expression of Bmi-1 increases self-renewal and proliferation of Atm(-/- NSCs to normal, indicating that defective proliferation in Atm(-/- NSCs is a consequence of down-regulation of Bmi-1. We also demonstrate that epidermal growth factor (EGF-induced Akt phosphorylation renders Bmi-1 resistant to the proteasomal degradation, leading to its stabilization and accumulation in the nucleus. However, inhibition of the Akt-dependent Bmi-1 stabilizing process by p38 MAPK signaling reduces the levels of Bmi-1. Treatment of the Atm(-/- NSCs with a specific p38 MAPK inhibitor SB203580 extended Bmi-1 posttranscriptional turnover and H2A ubiquitination in Atm(-/- NSCs. Our observations demonstrate the molecular basis underlying the impairment of self-renewal and proliferation in Atm(-/- NSCs through the p38 MAPK-Akt-Bmi-1-p21 signaling pathway.

  20. Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) regulate murine neural progenitor cell survival, proliferation, and differentiation.

    Science.gov (United States)

    Scharf, Eugene; May, Victor; Braas, Karen M; Shutz, Kristin C; Mao-Draayer, Yang

    2008-11-01

    Neural stem/progenitor cells (NPC) have gained wide interest over the last decade from their therapeutic potential, either through transplantation or endogenous replacement, after central nervous system (CNS) disease and damage. Whereas several growth factors and cytokines have been shown to promote NPC survival, proliferation, or differentiation, the identification of other regulators will provide much needed options for NPC self-renewal or lineage development. Although previous studies have shown that pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal peptide (VIP) can regulate stem/progenitor cells, the responses appeared variable. To examine the direct roles of these peptides in NPCs, postnatal mouse NPC cultures were withdrawn from epidermal growth factor (EGF) and fibroblastic growth factor (FGF) and maintained under serum-free conditions in the presence or absence of PACAP27, PACAP38, or VIP. The NPCs expressed the PAC1(short)null receptor isoform, and the activation of these receptors decreased progenitor cell apoptosis more than 80% from TUNEL assays and facilitated proliferation more than fivefold from bromodeoxyuridine (BrdU) analyses. To evaluate cellular differentiation, replicate control and peptide-treated cultures were examined for cell fate marker protein and transcript expression. In contrast with previous work, PACAP peptides downregulated NPC differentiation, which appeared consistent with the proliferation status of the treated cells. Accordingly, these results demonstrate that PACAP signaling is trophic and can maintain NPCs in a multipotent state. With these attributes, PACAP may be able to promote endogenous NPC self-renewal in the adult CNS, which may be important for endogenous self-repair in disease and ageing processes.

  1. Triptolide inhibits the proliferation of prostate cancer cells and down-regulates SUMO-specific protease 1 expression.

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    Weiwei Huang

    Full Text Available Recently, traditional Chinese medicine and medicinal herbs have attracted more attentions worldwide for its anti-tumor efficacy. Celastrol and Triptolide, two active components extracted from the Chinese herb Tripterygium wilfordii Hook F (known as Lei Gong Teng or Thunder of God Vine, have shown anti-tumor effects. Celastrol was identified as a natural 26 s proteasome inhibitor which promotes cell apoptosis and inhibits tumor growth. The effect and mechanism of Triptolide on prostate cancer (PCa is not well studied. Here we demonstrated that Triptolide, more potent than Celastrol, inhibited cell growth and induced cell death in LNCaP and PC-3 cell lines. Triptolide also significantly inhibited the xenografted PC-3 tumor growth in nude mice. Moreover, Triptolide induced PCa cell apoptosis through caspases activation and PARP cleavage. Unbalance between SUMOylation and deSUMOylation was reported to play an important role in PCa progression. SUMO-specific protease 1 (SENP1 was thought to be a potential marker and therapeutical target of PCa. Importantly, we observed that Triptolide down-regulated SENP1 expression in both mRNA and protein levels in dose-dependent and time-dependent manners, resulting in an enhanced cellular SUMOylation in PCa cells. Meanwhile, Triptolide decreased AR and c-Jun expression at similar manners, and suppressed AR and c-Jun transcription activity. Furthermore, knockdown or ectopic SENP1, c-Jun and AR expression in PCa cells inhibited the Triptolide anti-PCa effects. Taken together, our data suggest that Triptolide is a natural compound with potential therapeutic value for PCa. Its anti-tumor activity may be attributed to mechanisms involving down-regulation of SENP1 that restores SUMOylation and deSUMOyaltion balance and negative regulation of AR and c-Jun expression that inhibits the AR and c-Jun mediated transcription in PCa.

  2. GPC1 Regulated by miR-96-5p, Rather than miR-182-5p, in Inhibition of Pancreatic Carcinoma Cell Proliferation

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    Chunlong Li

    2014-04-01

    Full Text Available To determine the relationships between miR-96-5p/-182-5p and GPC1 in pancreatic cancer (PC, we conducted the population and in vitro studies. We followed 38 pancreatic cancer patients, measured and compared the expression of miR-96-5p/-182-5p, GPC1, characteristics and patients’ survival time of different miR-96-5p/-182-5p expression levels in PC tissues. In an in vitro study, we investigated the proliferation, cycle and apotosis in cells transfected with mimics/inhibitors of the two miRNAs, and determine their effects on GPC1 by dual-luciferase assay. In the follow-up study, we found that the expressions of miR-96-5p/-182-5p were lower/higher in PC tissues; patients with lower/higher levels of miR-96-5p/-182-5p suffered poorer characteristics and decreased survival time. In the in vitro study, the expressions of miR-96-5p/-182-5p were different in cells. Proliferation of cells transfected with miR-96-5p mimics/inhibitors was lower/higher in Panc-1/BxPC-3; when transfected with miR-182-5p mimics/inhibitors, proliferation of cells were higher/lower in AsPC-1/Panc-1. In a cell cycle study, panc-1 cells transfected with miR-96-5p mimics was arrested at G0/G1; BxPC-3 cells transfected with miR-96-5p inhibitors showed a significantly decrease at G0/G1; AsPC-1 cells transfected with miR-182-5p mimics was arrested at S; Panc-1 cells transfected with miR-182-5p inhibitors showed a decrease at S. MiR-96-5p mimics increased the apoptosis rate in Panc-1 cells, and its inhibitors decreased the apoptosis rate in BxPC-3. Dual luciferase assay revealed that GPC1 was regulated by miR-96-5p, not -182-5p. We found that miR-96-5p/-182-5p as good markers for PC; miR-96-5p, rather than -182-5p, inhibits GPC1 to suppress proliferation of PC cells.

  3. Emodin inhibits LOVO colorectal cancer cell proliferation via the regulation of the Bcl-2/Bax ratio and cytochrome c.

    Science.gov (United States)

    Ma, Liang; Li, Wusheng

    2014-10-01

    In this study, the effect of emodin and its mechanism of action were investigated in LOVO colorectal cancer cells. Cell growth was determined using a Cell Counting kit-8 assay, and the results demonstrated that emodin significantly inhibited the growth of LOVO cells in a concentration-dependent manner. In order to investigate the anticancer mechanism of emodin, reverse transcription polymerase chain reaction assays were performed to determine the B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated X protein (Bax) expression ratio in LOVO colorectal cancer cells following treatment with emodin. The results showed that emodin induced a significant increase in the Bax expression level and a marked reduction of the Bcl-2 expression level in LOVO cells. In addition, emodin was found to have an inhibitory effect on the mitochondrial membrane potential and the results from the western blot analysis revealed that cytochrome c was released from the mitochondria to the cytoplasm. In combination, these results suggest that emodin inhibits cancer cell growth via the regulation of the Bcl-2/Bax ratio and by its effect on the mitochondrial apoptosis pathway.

  4. The AhR is involved in the regulation of LoVo cell proliferation through cell cycle-associated proteins.

    Science.gov (United States)

    Yin, Jiuheng; Sheng, Baifa; Han, Bin; Pu, Aimin; Yang, Kunqiu; Li, Ping; Wang, Qimeng; Xiao, Weidong; Yang, Hua

    2016-05-01

    Some ingredients in foods can activate the aryl hydrocarbon receptor (AhR) and arrest cell proliferation. In this study, we hypothesized that 6-formylindolo [3, 2-b] carbazole (FICZ) arrests the cell cycle in LoVo cells (a colon cancer line) through the AhR. The AhR agonist FICZ and the AhR antagonist CH223191 were used to treat LoVo cells. Real-time PCR and Western blot analyses were performed to detect the expression of the AhR, CYP1A1, CDK4, cyclinD1, cyclin E, CDK2, P27, and pRb. The distribution and activation of the AhR were detected with immunofluorescence. A 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and flow cytometric analysis were performed to measure cell viability, cell cycle stage, and apoptosis. Our results show that FICZ inhibited LoVo cell proliferation by inducing G1 cell cycle arrest but had no effect on epithelial apoptosis. Further analysis found that FICZ downregulated cyclinD1 and upregulated p27 expression to arrest Rb phosphorylation. The downregulation of cyclinD1 and upregulation of p27 were abolished by co-treatment with CH223191. We conclude that the AhR, when activated by FICZ (an endogenous AhR ligand), can arrest the cell cycle and block LoVo cell proliferation.

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

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    Abel L Carcagno

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

  6. Long non-coding RNA MALAT-1 is downregulated in preeclampsia and regulates proliferation, apoptosis, migration and invasion of JEG-3 trophoblast cells.

    Science.gov (United States)

    Chen, Haiying; Meng, Tao; Liu, Xuemin; Sun, Manni; Tong, Chunxiao; Liu, Jing; Wang, He; Du, Juan

    2015-01-01

    Long non-coding RNA (lncRNA), as a newly identified subset of the transcriptome, has been implicated in a variety of physiological and pathological processes. Metastasis associated lung adenocarcinoma transcript-1 (MALAT-1), a lncRNA that was initially detected in the metastatic lung cancer, was reported to be overexpressed in placenta previa increta/percreta (I/P), which is caused by excessive trophoblast invasion. However, the role of MALAT-1 in the regulation of trophoblast behavior is not fully understood. In this study, we first examined the expression of MALAT-1 in the placentas from the patients with preeclampsia, the pathology of which is associated with inadequate trophoblast invasion, and found that the expression of MALAT-1 was downregulated in the preeclamptic placentas as compared to the normal placentas. We further investigated the function of MALAT-1 in JEG-3 trophoblast cell line using short interfering RNA (siRNA) against MALAT-1 transcripts. Silencing of MALAT-1 in JEG-3 cells suppressed proliferation and induced cell cycle arrest at G0/G1 phase. Reduced expression of MALAT-1 by RNA interference resulted in enhanced apoptosis in JEG-3 cells, accompanied with elevated levels of the pro-apoptotic proteins including cleaved caspase-3, cleaved caspase-9 and cleaved poly (ADP-ribose) polymerase-1 (PARP-1). Moreover, the migration rate and the invasiveness of JEG-3 cells were suppressed when MALAT-1 was downregulated. In summary, our results suggest that MALAT-1 may play an important role in the regulation of proliferation, cell cycle, apoptosis, migration and invasion of trophoblast cells, and under-expression of MALAT-1 during early placentation may be involved in the pathogenesis of preeclampsia.

  7. Gamma aminobutyric acid B and 5-hydroxy tryptamine 2A receptors functional regulation during enhanced liver cell proliferation by GABA and 5-HT chitosan nanoparticles treatment.

    Science.gov (United States)

    Shilpa, Joy; Pretty, Mary Abraham; Anitha, Malat; Paulose, Cheramadathikudyil Skaria

    2013-09-01

    Liver is one of the major organs in vertebrates and hepatocytes are damaged by many factors. The liver cell maintenance and multiplication after injury and treatment gained immense interest. The present study investigated the role of Gamma aminobutyric acid (GABA) and serotonin or 5-hydroxytryptamine (5-HT) coupled with chitosan nanoparticles in the functional regulation of Gamma aminobutyric acid B and 5-hydroxy tryptamine 2A receptors mediated cell signaling mechanisms, extend of DNA methylation and superoxide dismutase activity during enhanced liver cell proliferation. Liver injury was achieved by partial hepatectomy of male Wistar rats and the GABA and 5-HT chitosan nanoparticles treatments were given intraperitoneally. The experimental groups were sham operated control (C), partially hepatectomised rats with no treatment (PHNT), partially hepatectomised rats with GABA chitosan nanoparticle (GCNP), 5-HT chitosan nanoparticle (SCNP) and a combination of GABA and 5-HT chitosan nanoparticle (GSCNP) treatments. In GABA and 5-HT chitosan nanoparticle treated group there was a significant decrease (PGABA and 5-HT chitosan nanoparticles induced liver cell proliferation which has therapeutic significance in liver disease management.

  8. Hematopoiesis: Gap Junction Intercellular Communication is Likely to be Involved in Regulation of Stroma-dependent Proliferation of Hemopoietic Stem Cells.

    Science.gov (United States)

    Ploemacher, ROB E.; Mayen, ANGELIQUE E. M.; De Koning, ALEXANDRA E.; Krenacs, TIBOR; Rosendaal, MARTIN

    2000-01-01

    The 80-100 fold increased immunohistological expression of the Gap Junction (GJ) protein Connexin-43 in murine bone marrow during the neonatal period and directly following cytoreductive treatment of adult mice suggests that the regulation of stem cell proliferation may involve GJ Intercellular Communication (GJIC). Using a series of stromal cell lines from foetal liver and neonatal bone marrow we observed that the percentage of cells with GJIC, as indicated by dye-coupling using microinjection of lucifer yellow, correlated with the stromal support for late appearing clones formed by primitive stem cells (CAFC week 3-5). In order to functionally block all GJIC between mutual stromal cells and stromal cells and hemopoietic cells, in long-term stroma-supported flask (LTC) and CAFC cultures, the lipophilic compounds amphotericin-B (AB), nystatin, alpha-glycyrrhetinic acid, tetraphenylboron, dipicrylamine and arachidonic acid were tested for their effect on GJIC and CAFC support. Only AB and nystatin, which induced complete and prolonged GJIC blockade, were able to dramatically inhibit cobblestone area (CA) formation and CFU-C generation in LTC. This inhibition could be fully abrogated by withdrawing AB within the first 2 weeks of culture. Low AB concentrations stimulated CA formation. The AB-mediated inhibition of hemopoiesis probably involved direct stromal contact with stem cells because a) AB did not inhibit CFU-C generation when stem cells were cultured in trans-well inserts above the stroma; b) conditioned media from AB-containing or normal LTC did not inhibit colony formation by normal cells in semi-solid, non-stromal cultures, and c) AB did not inhibit colony formation by bone marrow cells in semi-solid culture nor did it inhibit growth or maintenance of stromal cells. In addition, The inhibition of hemopoiesis by AB could also not be explained by changes in the amount of cytokine and chemokine transcripts, including TGF-b1, in AB-blocked stromal cells. Our

  9. p38MAPK activation is involved in androgen-independent proliferation of human prostate cancer cells by regulating IL-6 secretion

    International Nuclear Information System (INIS)

    Increased levels of serum interleukin-6 (IL-6) are frequently observed in patients with advanced, hormone-refractory prostate cancer. However, the precise mechanism of IL-6 regulation is still largely unknown. Since prostate cancer gradually progresses to an androgen-independent state despite the stress caused by various therapeutic agents, we hypothesized the stress-activated protein kinases (SAPKs) involvement in androgen-independent growth or IL-6 secretion of prostate cancer cells. Using PC-3 and DU145 human prostate cancer cells, we analyzed the role of SAPKs in IL-6 mediated cell growth and found that the p38MAPK and JNK are involved in androgen-independent cancer cell growth. Furthermore, IL-6 secretion by PC-3 and DU145 cells was significantly suppressed by SAPKs inhibitor, especially by p38MAPK inhibitor SB203580, but not by JNK inhibitor SP600125 nor by MEK inhibitor, PD98059. These results raised the possibility that the IL-6 mediated androgen-independent proliferation of PC-3 and DU145 cells is regulated at least partly via SAPKs signaling pathway especially through p38MAPK activation

  10. Odd-skipped related 2 regulates genes related to proliferation and development

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Shinji, E-mail: skawai@dent.osaka-u.ac.jp [Department of Oral Frontier Biology, Osaka University Graduate School of Dentistry, Suita-Osaka 565-0871 (Japan); Abiko, Yoshimitsu [Department of Biochemistry, Nihon University School of Dentistry at Matsudo, Matsudo-Chiba 271-8587 (Japan); Amano, Atsuo [Department of Oral Frontier Biology, Osaka University Graduate School of Dentistry, Suita-Osaka 565-0871 (Japan)

    2010-07-23

    Cell proliferation is a biological process in which chromosomes replicate in one cell and equally divide into two daughter cells. Our previous findings suggested that Odd-skipped related 2 (Osr2) plays an important role in cellular quiescence and proliferation under epigenetic regulation. However, the mechanism used by Osr2 to establish and maintain proliferation is unknown. To examine the functional role of Osr2 in cell proliferation, we analyzed its downstream target genes using microarray analysis following adenovirus-induced overexpression of Osr2 as well as knockdown with Osr2 siRNA, which showed that Osr2 regulates a multitude of genes involved in proliferation and the cell cycle, as well as development. Additional proliferation assays also indicated that Osr2 likely functions to elicit cell proliferation. Together, these results suggest that Osr2 plays important roles in proliferation and development.

  11. MiR-27a targets sFRP1 in hFOB cells to regulate proliferation, apoptosis and differentiation.

    Directory of Open Access Journals (Sweden)

    Donggeng Guo

    Full Text Available MicroRNAs (miRNAs play a key role in the regulation of almost all the physiological and pathological processes, including bone metabolism. Recent studies have suggested that miR-27 might play a key role in osteoblast differentiation and bone formation. Increasing evidence indicates that the canonical Wnt signaling pathway contributes to different stages of bone formation. In this study, we identify miR-27a can promote osteoblast differentiation by repressing a new target, secreted frizzled-related proteins 1 (sFRP1 expression at the transcriptional level. Here, 21 candidate targets of miR-27a involved in canonical Wnt/β-catenin signaling were predicted, and a significant decrease in sFRP1 luciferase activity was observed both in 293T and MG63 cells co-transfected with the matched luciferase reporter constructs and miR-27a mimic. Furthermore, the presence of exogenous miR-27a significantly decreased sFRP1 mRNA and protein expression in hFOB1.19 cells during both proliferation and osteogenic differentiation. The over-expression of miR-27a or knockdown sFRP1 significantly increased the percentage of apoptotic hFOBs, the percentage of cells in the G2-M phase of the cell cycle and the expression of key osteoblastic markers, including ALP, SPP1, RUNX2 and ALP activity. Over-expression of miR-27a or knockdown of endogenous sFRP1 led to an accumulation of β-catenin in hFOBs. In the present study, we demonstrate that miR-27a induced gene silencing effect is a vital mechanism contributing to bone metabolism in hFOB cells in vitro, which is partly affected by the post-transcriptional regulation of sFRP1, during osteoblast proliferation, apoptosis and differentiation.

  12. TNFα signaling regulates cystic epithelial cell proliferation through Akt/mTOR and ERK/MAPK/Cdk2 mediated Id2 signaling.

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    Julie X Zhou

    Full Text Available Tumor necrosis factor alpha (TNFα is present in cyst fluid and promotes cyst growth in autosomal dominant polycystic kidney disease (ADPKD. However, the cross-talk between TNFα and PKD associated signaling pathways remains elusive. In this study, we found that stimulation of renal epithelial cells with TNFα or RANKL (receptor activator of NF-κB ligand, a member of the TNFα cytokine family, activated either the PI3K pathway, leading to AKT and mTOR mediated the increase of Id2 protein, or MAPK and Cdk2 to induce Id2 nuclear translocation. The effects of TNFα/RANKL on increasing Id2 protein and its nuclear translocation caused significantly decreased mRNA and protein levels of the Cdk inhibitor p21, allowing increased cell proliferation. TNFα levels increase in cystic kidneys in response to macrophage infiltration and thus might contribute to cyst growth and enlargement during the progression of disease. As such, this study elucidates a novel mechanism for TNFα signaling in regulating cystic renal epithelial cell proliferation in ADPKD.

  13. bantam miRNA is important for Drosophila blood cell homeostasis and a regulator of proliferation in the hematopoietic progenitor niche

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    Lam, Victoria; Tokusumi, Tsuyoshi; Tokusumi, Yumiko; Schulz, Robert A., E-mail: rschulz@nd.edu

    2014-10-24

    Highlights: • bantam miRNA is endogenously expressed in the hematopoietic progenitor niche. • bantam is necessary and sufficient to induce cellular proliferation in the PSC. • bantam is upstream of the Insulin Receptor signaling pathway. • A model for positive regulation of hematopoietic niche growth is proposed. - Abstract: The Drosophila hematopoietic system is utilized in this study to gain novel insights into the process of growth control of the hematopoietic progenitor niche in blood development. The niche microenvironment is an essential component controlling the balance between progenitor populations and differentiated, mature blood cells and has been shown to lead to hematopoietic malignancies in humans when misregulated. MicroRNAs are one class of regulators associated with blood malignancies; however, there remains a relative paucity of information about the role of miRNAs in the niche. Here we demonstrate that bantam miRNA is endogenously active in the Drosophila hematopoietic progenitor niche, the posterior signaling center (PSC), and functions in the primary hematopoietic organ, the lymph gland, as a positive regulator of growth. Loss of bantam leads to a significant reduction in the PSC and overall lymph gland size, as well as a loss of the progenitor population and correlative premature differentiation of mature hemocytes. Interestingly, in addition to being essential for proper lymph gland development, we have determined bantam to be a novel upstream component of the insulin signaling cascade in the PSC and have unveiled dMyc as one factor central to bantam activity. These important findings identify bantam as a new hematopoietic regulator, place it in an evolutionarily conserved signaling pathway, present one way in which it is regulated, and provide a mechanism through which it facilitates cellular proliferation in the hematopoietic niche.

  14. bantam miRNA is important for Drosophila blood cell homeostasis and a regulator of proliferation in the hematopoietic progenitor niche

    International Nuclear Information System (INIS)

    Highlights: • bantam miRNA is endogenously expressed in the hematopoietic progenitor niche. • bantam is necessary and sufficient to induce cellular proliferation in the PSC. • bantam is upstream of the Insulin Receptor signaling pathway. • A model for positive regulation of hematopoietic niche growth is proposed. - Abstract: The Drosophila hematopoietic system is utilized in this study to gain novel insights into the process of growth control of the hematopoietic progenitor niche in blood development. The niche microenvironment is an essential component controlling the balance between progenitor populations and differentiated, mature blood cells and has been shown to lead to hematopoietic malignancies in humans when misregulated. MicroRNAs are one class of regulators associated with blood malignancies; however, there remains a relative paucity of information about the role of miRNAs in the niche. Here we demonstrate that bantam miRNA is endogenously active in the Drosophila hematopoietic progenitor niche, the posterior signaling center (PSC), and functions in the primary hematopoietic organ, the lymph gland, as a positive regulator of growth. Loss of bantam leads to a significant reduction in the PSC and overall lymph gland size, as well as a loss of the progenitor population and correlative premature differentiation of mature hemocytes. Interestingly, in addition to being essential for proper lymph gland development, we have determined bantam to be a novel upstream component of the insulin signaling cascade in the PSC and have unveiled dMyc as one factor central to bantam activity. These important findings identify bantam as a new hematopoietic regulator, place it in an evolutionarily conserved signaling pathway, present one way in which it is regulated, and provide a mechanism through which it facilitates cellular proliferation in the hematopoietic niche

  15. Nuclear envelope proteins Nesprin2 and LaminA regulate proliferation and apoptosis of vascular endothelial cells in response to shear stress.

    Science.gov (United States)

    Han, Yue; Wang, Lu; Yao, Qing-Ping; Zhang, Ping; Liu, Bo; Wang, Guo-Liang; Shen, Bao-Rong; Cheng, Binbin; Wang, Yingxiao; Jiang, Zong-Lai; Qi, Ying-Xin

    2015-05-01

    The dysfunction of vascular endothelial cells (ECs) influenced by flow shear stress is crucial for vascular remodeling. However, the roles of nuclear envelope (NE) proteins in shear stress-induced EC dysfunction are still unknown. Our results indicated that, compared with normal shear stress (NSS), low shear stress (LowSS) suppressed the expression of two types of NE proteins, Nesprin2 and LaminA, and increased the proliferation and apoptosis of ECs. Targeted small interfering RNA (siRNA) and gene overexpression plasmid transfection revealed that Nesprin2 and LaminA participate in the regulation of EC proliferation and apoptosis. A protein/DNA array was further used to detect the activation of transcription factors in ECs following transfection with target siRNAs and overexpression plasmids. The regulation of AP-2 and TFIID mediated by Nesprin2 and the activation of Stat-1, Stat-3, Stat-5 and Stat-6 by LaminA were verified under shear stress. Furthermore, using Ingenuity Pathway Analysis software and real-time RT-PCR, the effects of Nesprin2 or LaminA on the downstream target genes of AP-2, TFIID, and Stat-1, Stat-3, Stat-5 and Stat-6, respectively, were investigated under LowSS. Our study has revealed that NE proteins are novel mechano-sensitive molecules in ECs. LowSS suppresses the expression of Nesprin2 and LaminA, which may subsequently modulate the activation of important transcription factors and eventually lead to EC dysfunction.

  16. Regulation of Schwann cell proliferation and migration by miR-1 targeting brain-derived neurotrophic factor after peripheral nerve injury

    Science.gov (United States)

    Yi, Sheng; Yuan, Ying; Chen, Qianqian; Wang, Xinghui; Gong, Leilei; Liu, Jie; Gu, Xiaosong; Li, Shiying

    2016-01-01

    Peripheral nerve injury is a global problem that causes disability and severe socioeconomic burden. Brain-derived neurotrophic factor (BDNF) benefits peripheral nerve regeneration and becomes a promising therapeutic molecule. In the current study, we found that microRNA-1 (miR-1) directly targeted BDNF by binding to its 3′-UTR and caused both mRNA degradation and translation suppression of BDNF. Moreover, miR-1 induced BDNF mRNA degradation primarily through binding to target site 3 rather than target site 1 or 2 of BDNF 3′-UTR. Following rat sciatic nerve injury, a rough inverse correlation was observed between temporal expression profiles of miR-1 and BDNF in the injured nerve. The overexpression or silencing of miR-1 in cultured Schwann cells (SCs) inhibited or enhanced BDNF secretion from the cells, respectively, and also suppressed or promoted SC proliferation and migration, respectively. Interestingly, BDNF knockdown could attenuate the enhancing effect of miR-1 inhibitor on SC proliferation and migration. These findings will contribute to the development of a novel therapeutic strategy for peripheral nerve injury, which overcomes the limitations of direct administration of exogenous BDNF by using miR-1 to regulate endogenous BDNF expression. PMID:27381812

  17. MAPK signaling pathway regulates p27 phosphorylation at threonin 187 as part of the mechanism triggered by early-weaning to induce cell proliferation in rat gastric mucosa.

    Directory of Open Access Journals (Sweden)

    Luciana H Osaki

    Full Text Available During rat postnatal development, gastric cell proliferation and differentiation depend on many elements, which include dietary pattern, hormones, growth factors and their signaling pathways. Among them, EGFR activity is increased through MAPK and Src cascades in response to early weaning that represents the abrupt transition from milk to solid food. We herein investigated the direct involvement of ERK pathway in the control of cell cycle progression during early weaning, and studied the specific role of p27. At 15 days, Wistar rats were separated from dams, fed with powdered chow and daily injected with PD98059 (MEK inhibitor, 300 µg/kg or 0.5% DMSO (control. By using HE staining and immunohistochemistry for PCNA, we respectively detected mitotic (MI and proliferative (PI indices in 18-day-old pups, and observed that both were reduced by PD98059. As cell cycle-related proteins (cyclin E, CDK2, cyclin D1, CDK4, p21 and p27 are involved in proliferative regulation, we compared samples obtained at 17 days in the morning (17 d and evening (17.5 d. We found that they were not altered after ERK inhibition, but cyclin D1, p21 and p27 levels changed throughout the day in the control group. As p27 activity depends on its integrity, we studied p27 phosphorylation (threonin 187, and observed that ERK inhibition reduced this process. We suggest that MAPK pathway interferes in the regulation of p27 function in the gastric mucosa during early weaning, possibly by controlling its degradation, and altogether this mechanism might contribute to the increase of epithelial proliferation at this condition.

  18. 5-alpha-reductase type I (SRD5A1 is up-regulated in non-small cell lung cancer but does not impact proliferation, cell cycle distribution or apoptosis

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    Kapp Friedrich G

    2012-01-01

    Full Text Available Abstract Background Non-small cell lung cancer (NSCLC is one of the most frequent malignancies and has a high mortality rate due to late detection and lack of efficient treatments. Identifying novel drug targets for this indication may open the way for new treatment strategies. Comparison of gene expression profiles of NSCLC and normal adjacent tissue (NAT allowed to determine that 5-alpha-reductase type I (SRD5A1 was up-regulated in NSCLC compared to NAT. This raised the question whether SRD5A1 was involved in sustained proliferation and survival of NSCLC. Methods siRNA-mediated silencing of SRD5A1 was performed in A549 and NCI-H460 lung cancer cell lines in order to determine the impact on proliferation, on distribution during the different phases of the cell cycle, and on apoptosis/necrosis. In addition, lung cancer cell lines were treated with 4-azasteroids, which specifically inhibit SRD5A1 activity, and the effects on proliferation were measured. Statistical analyses using ANOVA and post-hoc Tamhane-T2-test were performed. In the case of non-parametric data, the Kruskal-Wallis test and the post-hoc Mann-Whitney-U-test were used. Results The knock-down of SRDA51 expression was very efficient with the SRD5A1 transcripts being reduced to 10% of control levels. Knock-down efficiency was furthermore confirmed at the protein level. However, no effect of SRD5A1 silencing was observed in the proliferation assay, the cell cycle analysis, and the apoptosis/necrosis assay. Treatment of lung cancer cell lines with 4-azasteroids did not significantly inhibit proliferation. Conclusions In summary, the results suggest that SRD5A1 is not a crucial enzyme for the sustained proliferation of NSCLC cell lines.

  19. MicroRNA profiling in subventricular zone after stroke: MiR-124a regulates proliferation of neural progenitor cells through Notch signaling pathway.

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    Xian Shuang Liu

    Full Text Available BACKGROUND: The Notch signaling pathway regulates adult neurogenesis under physiological and pathophysiological conditions. MicroRNAs are small non-coding RNA molecules that regulate gene expression. The present study investigated the effect of miR-124a on the Notch signaling pathway in stroke-induced neurogenesis. METHODOLOGY AND PRINCIPAL FINDINGS: We found that adult rats subjected to focal cerebral ischemia exhibited substantial reduction of miR-124a expression, a neuron specific miRNA, in the neural progenitor cells of the subventricular zone (SVZ of the lateral ventricle, which was inversely associated with activation of Notch signals. In vitro, transfection of neural progenitor cells harvested from the SVZ of adult rat with miR-124a repressed Jagged-1 (JAG1, a ligand of Notch, in a luciferase construct containing the JAG1 target site. Introduction of miR-124a in neural progenitor cells significantly reduced JAG1 transcript and protein levels, leading to inactivation of Notch signals. Transfection of neural progenitor cells with miR-124a significantly reduced progenitor cell proliferation and promoted neuronal differentiation measured by an increase in the number of Doublecortin positive cells, a marker of neuroblasts. Furthermore, introduction of miR-124a significantly increased p27Kip1 mRNA and protein levels, a downstream target gene of the Notch signaling pathway. CONCLUSIONS: Collectively, our study demonstrated that in vivo, stroke alters miRNA expression in SVZ neural progenitor cells and that in vitro, miR-124a mediates stroke-induced neurogenesis by targeting the JAG-Notch signaling pathway.

  20. Lentiviral vector-mediated down-regulation of Notch1 in endometrial stem cells results in proliferation and migration in endometriosis.

    Science.gov (United States)

    He, Hong; Liu, Rong; Xiong, Wei; Pu, Demin; Wang, Shixuan; Li, Tian

    2016-10-15

    The recent characterization of stem/progenitor cells in the endometrium has shed new light for pathogenesis of endometriosis. The present study was undertaken to investigate the role of Notch1, known as a cell fate regulator, in the mechanism of endometriosis. Influence of Notch1 on endometrial stem cells proliferation and migration was evaluated by knocking down Notch1 expression using shRNA. Furthermore, human endometrial stromal and epithelial stem cells with or without LV-Notch1-shRNA were injected into the peritoneal cavity of nude mice, to assess the in vivo effects of a specific antagonist of Notch1 on the progression of endometriosis. The results showed that LV-Notch1-shRNA led to a significant decline of clonogenicity and migration in human endometrial stem cells in vitro, as well as the size of endometriotic lesions in murine models. These data provide evidence that specific inhibition of Notch1 alters endometriotic tissue growth and progression, and may represent a promising potential therapeutic avenue. PMID:27389878

  1. Down-regulation of 5-HT1B and 5-HT1D receptors inhibits proliferation, clonogenicity and invasion of human pancreatic cancer cells.

    Directory of Open Access Journals (Sweden)

    Nilgun Gurbuz

    Full Text Available Pancreatic ductal adenocarcinoma is characterized by extensive local tumor invasion, metastasis and early systemic dissemination. The vast majority of pancreatic cancer (PaCa patients already have metastatic complications at the time of diagnosis, and the death rate of this lethal type of cancer has increased over the past decades. Thus, efforts at identifying novel molecularly targeted therapies are priorities. Recent studies have suggested that serotonin (5-HT contributes to the tumor growth in a variety of cancers including prostate, colon, bladder and liver cancer. However, there is lack of evidence about the impact of 5-HT receptors on promoting pancreatic cancer. Having considered the role of 5-HT-1 receptors, especially 5-HT1B and 5-HT1D subtypes in different types of malignancies, the aim of this study was to investigate the role of 5-HT1B and 5-HT1D receptors in PaCa growth and progression and analyze their potential as cytotoxic targets. We found that knockdown of 5-HT1B and 5-HT1D receptors expression, using specific small interfering RNA (siRNA, induced significant inhibition of proliferation and clonogenicity of PaCa cells. Also, it significantly suppressed PaCa cells invasion and reduced the activity of uPAR/MMP-2 signaling and Integrin/Src/Fak-mediated signaling, as integral tumor cell pathways associated with invasion, migration, adhesion, and proliferation. Moreover, targeting 5-HT1B and 5-HT1D receptors down-regulates zinc finger ZEB1 and Snail proteins, the hallmarks transcription factors regulating epithelial-mesenchymal transition (EMT, concomitantly with up-regulating of claudin-1 and E-Cadherin. In conclusion, our data suggests that 5-HT1B- and 5-HT1D-mediated signaling play an important role in the regulation of the proliferative and invasive phenotype of PaCa. It also highlights the therapeutic potential of targeting of 5-HT1B/1D receptors in the treatment of PaCa, and opens a new avenue for biomarkers identification

  2. Down-regulation of 5-HT1B and 5-HT1D receptors inhibits proliferation, clonogenicity and invasion of human pancreatic cancer cells.

    Directory of Open Access Journals (Sweden)

    Nilgun Gurbuz

    Full Text Available Pancreatic ductal adenocarcinoma is characterized by extensive local tumor invasion, metastasis and early systemic dissemination. The vast majority of pancreatic cancer (PaCa patients already have metastatic complications at the time of diagnosis, and the death rate of this lethal type of cancer has increased over the past decades. Thus, efforts at identifying novel molecularly targeted therapies are priorities. Recent studies have suggested that serotonin (5-HT contributes to the tumor growth in a variety of cancers including prostate, colon, bladder and liver cancer. However, there is lack of evidence about the impact of 5-HT receptors on promoting pancreatic cancer. Having considered the role of 5-HT-1 receptors, especially 5-HT1B and 5-HT1D subtypes in different types of malignancies, the aim of this study was to investigate the role of 5-HT1B and 5-HT1D receptors in PaCa growth and progression and analyze their potential as cytotoxic targets. We found that knockdown of 5-HT1B and 5-HT1D receptors expression, using specific small interfering RNA (siRNA, induced significant inhibition of proliferation and clonogenicity of PaCa cells. Also, it significantly suppressed PaCa cells invasion and reduced the activity of uPAR/MMP-2 signaling and Integrin/Src/Fak-mediated signaling, as integral tumor cell pathways associated with invasion, migration, adhesion, and proliferation. Moreover, targeting 5-HT1B and 5-HT1D receptors down-regulates zinc finger ZEB1 and Snail proteins, the hallmarks transcription factors regulating epithelial-mesenchymal transition (EMT, concomitantly with up-regulating of claudin-1 and E-Cadherin. In conclusion, our data suggests that 5-HT1B- and 5-HT1D- mediated signaling play an important role in the regulation of the proliferative and invasive phenotype of PaCa. It also highlights the therapeutic potential of targeting of 5-HT1B/1D receptors in the treatment of PaCa, and opens a new avenue for biomarkers identification

  3. Down-regulation of 5-HT1B and 5-HT1D receptors inhibits proliferation, clonogenicity and invasion of human pancreatic cancer cells.

    Science.gov (United States)

    Gurbuz, Nilgun; Ashour, Ahmed A; Alpay, S Neslihan; Ozpolat, Bulent

    2014-01-01

    Pancreatic ductal adenocarcinoma is characterized by extensive local tumor invasion, metastasis and early systemic dissemination. The vast majority of pancreatic cancer (PaCa) patients already have metastatic complications at the time of diagnosis, and the death rate of this lethal type of cancer has increased over the past decades. Thus, efforts at identifying novel molecularly targeted therapies are priorities. Recent studies have suggested that serotonin (5-HT) contributes to the tumor growth in a variety of cancers including prostate, colon, bladder and liver cancer. However, there is lack of evidence about the impact of 5-HT receptors on promoting pancreatic cancer. Having considered the role of 5-HT-1 receptors, especially 5-HT1B and 5-HT1D subtypes in different types of malignancies, the aim of this study was to investigate the role of 5-HT1B and 5-HT1D receptors in PaCa growth and progression and analyze their potential as cytotoxic targets. We found that knockdown of 5-HT1B and 5-HT1D receptors expression, using specific small interfering RNA (siRNA), induced significant inhibition of proliferation and clonogenicity of PaCa cells. Also, it significantly suppressed PaCa cells invasion and reduced the activity of uPAR/MMP-2 signaling and Integrin/Src/Fak-mediated signaling, as integral tumor cell pathways associated with invasion, migration, adhesion, and proliferation. Moreover, targeting 5-HT1B and 5-HT1D receptors down-regulates zinc finger ZEB1 and Snail proteins, the hallmarks transcription factors regulating epithelial-mesenchymal transition (EMT), concomitantly with up-regulating of claudin-1 and E-Cadherin. In conclusion, our data suggests that 5-HT1B- and 5-HT1D- mediated signaling play an important role in the regulation of the proliferative and invasive phenotype of PaCa. It also highlights the therapeutic potential of targeting of 5-HT1B/1D receptors in the treatment of PaCa, and opens a new avenue for biomarkers identification, and valuable new

  4. P53-regulated long non-coding RNA TUG1 affects cell proliferation in human non-small cell lung cancer, partly through epigenetically regulating HOXB7 expression

    OpenAIRE

    Zhang, E-b; Yin, D-d; M. Sun; Kong, R.; Liu, X-h; You, L-h; Han, L.; Xia, R; Wang, K-m; Yang, J-s; De, W; Shu, Y-q; Wang, Z-X

    2014-01-01

    Recently, a novel class of transcripts, long non-coding RNAs (lncRNAs), is being identified at a rapid pace. These RNAs have critical roles in diverse biological processes, including tumorigenesis. Here we report that taurine-upregulated gene 1 (TUG1), a 7.1-kb lncRNA, recruiting and binding to polycomb repressive complex 2 (PRC2), is generally downregulated in non-small cell lung carcinoma (NSCLC) tissues. In a cohort of 192 NSCLC patients, the lower expression of TUG1 was associated with a ...

  5. A novel hypoxia-induced miR-147a regulates cell proliferation through a positive feedback loop of stabilizing HIF-1α

    Science.gov (United States)

    Wang, Fan; Zhang, Haoxiang; Xu, Naihan; Huang, Nunu; Tian, Caiming; Ye, Anlin; Hu, Guangnan; He, Jie; Zhang, Yaou

    2016-01-01

    ABSTRACT Hypoxia is a general event in solid tumor growth. Therefore, induced cellular responses by hypoxia are important for tumorigenesis and tumor growth. MicroRNAs (miRNAs) have recently emerged as important regulators of hypoxia induced cellular responses. Here we report that miR-147a is a novel and crucial hypoxia induced miRNA. HIF-1α up-regulates the expression of miR-147a, and miR-147a in turn stabilizes and accumulates HIF-1α protein via directly targeting HIF-3α, a dominant negative regulator of HIF-1α. Subsequent studies in xenograft mouse model reveal that miR-147a is capable of inhibiting tumor growth. Collectively, these data demonstrate a positive feedback loop between HIF-1α, miR-147a and HIF-3α, which provide a new insight into the mechanism of miR-147a induced cell proliferation arrest under hypoxia. PMID:27260617

  6. The Role of Matrine and Mitogen-Ativated Protein Kinase/Extracellular Signal-Regulated Kinase Signal Transduction in the Inhibition of the Proliferation and Migration of Human Umbilical Veins Endothelial Cells Induced by Lung Cancer cells

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    Ming BAI

    2009-07-01

    Full Text Available Background and objective Matrine, one of the major alkaloid components of the traditional Chinese medicine Sophora roots, has a wide range of pharmacological effects including anti-inflammatory activities, growth inhibition and induction of cell differentiation and apoptosis. Motigen-activated protein kinase (MAPK/extracellular signal-regulated kinase (ERK has found to be a crucial signaling pathway in endothelial cells. The aim of this study is to investigate the role of Matrine and MAPK/ERK signal transduction in the inhibition of the proliferation and migration of human umbilical veins endothelial cells (HUVECs induced by lung cancer cells. Methods HUVECs were cultured with A549CM. Mat or PD98059 (i.e PD, specific inhibitor of MAPK/ERK, was added into the A549CM. The proliferation of the HUVECs was measured by cell counting. The migration of the HUVECs was observed by wound healing assay. The expression levels of ERK and p-ERK protein were detected by Western Blot analysis. Results On 24 hours after intervention, the A549CM significantly stimulated the proliferation, migration and expression of p-ERK of HUVECs. Compared with the A549CM group, Mat significantly inhibited the proliferation, migration and p-ERK expression of HUVECs induced by A549CM. While PD only decreased the proliferation and p-ERK expression of HUVECs induced by A549CM. PD had no effect in the migration of HUVECs. Conclusion The results demonstrated that Mat and PD98059 can effectively decrease proliferation and expression of p-ERK of HUVECs induced by A549CM. Furthermore Mat can also inhibit migration of HUVECs induced by A549CM that did not changed by PD98059. These data implied that suppressing MAPK/ERK signal transduction may play the crucial role in resisting lung cacinoma angiogenesis with Mat.

  7. Peroxisome Proliferator-Activated Receptor Gamma Negatively Regulates the Differentiation of Bone Marrow-Derived Mesenchymal Stem Cells Toward Myofibroblasts in Liver Fibrogenesis

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    Shuangshuang Jia

    2015-11-01

    Full Text Available Background/Aims: Bone marrow-derived mesenchymal stem cells (BMSCs have been confirmed to have capacity to differentiate toward hepatic myofibroblasts, which contribute to fibrogenesis in chronic liver diseases. Peroxisome proliferator-activated receptor gamma (PPARγ, a ligand-activated transcription factor, has gained a great deal of recent attention as it is involved in fibrosis and cell differentiation. However, whether it regulates the differentiation of BMSCs toward myofibroblasts remains to be defined. Methods: Carbon tetrachloride or bile duct ligation was used to induce mouse liver fibrosis. Expressions of PPARγ, α-smooth muscle actin, collagen α1 (I and collagen α1 (III were detected by real-time RT-PCR and Western blot or immunofluorescence assay. Results: PPARγ expression was decreased in mouse fibrotic liver. In addition, PPARγ was declined during the differentiation of BMSCs toward myofibroblasts induced by transforming growth factor β1. Activation of PPARγ stimulated by natural or synthetic ligands suppressed the differentiation of BMSCs. Additionally, knock down of PPARγ by siRNA contributed to BMSC differentiation toward myofibroblasts. Furthermore, PPARγ activation by natural ligand significantly inhibited the differentiation of BMSCs toward myofibroblasts in liver fibrogenesis and alleviated liver fibrosis. Conclusions: PPARγ negatively regulates the differentiation of BMSCs toward myofibroblasts, which highlights a further mechanism implicated in the BMSC differentiation.

  8. Regulation of the p27Kip1 tumor suppressor by miR-221 and miR-222 promotes cancer cell proliferation

    Science.gov (United States)

    le Sage, Carlos; Nagel, Remco; Egan, David A; Schrier, Mariette; Mesman, Elly; Mangiola, Annunziato; Anile, Corrado; Maira, Giulio; Mercatelli, Neri; Ciafrè, Silvia Anna; Farace, Maria Giulia; Agami, Reuven

    2007-01-01

    MicroRNAs (miRNAs) are potent post-transcriptional regulators of protein coding genes. Patterns of misexpression of miRNAs in cancer suggest key functions of miRNAs in tumorigenesis. However, current bioinformatics tools do not entirely support the identification and characterization of the mode of action of such miRNAs. Here, we used a novel functional genetic approach and identified miR-221 and miR-222 (miR-221&222) as potent regulators of p27Kip1, a cell cycle inhibitor and tumor suppressor. Using miRNA inhibitors, we demonstrate that certain cancer cell lines require high activity of miR-221&222 to maintain low p27Kip1 levels and continuous proliferation. Interestingly, high levels of miR-221&222 appear in glioblastomas and correlate with low levels of p27Kip1 protein. Thus, deregulated expression of miR-221&222 promotes cancerous growth by inhibiting the expression of p27Kip1. PMID:17627278

  9. miR-18a promotes cell proliferation of esophageal squamous cell carcinoma cells by increasing cylin D1 via regulating PTEN-PI3K-AKT-mTOR signaling axis.

    Science.gov (United States)

    Zhang, Weiguo; Lei, Caipeng; Fan, Junli; Wang, Jing

    2016-08-12

    Esophageal squamous cell carcinoma (ESCC) is one of the lethal cancers with a high incidence rate in Asia. Cyclin D1 is overexpressed and plays an important role in the carcinogenesis of ESCC; however the mechanism of the deregulation of Cyclin D1 in ESCC remains to be determined. In the study, we found that miR-18a promotes the expression Cyclin D1 by targeting PTEN in eophageal squamous cell carcinoma TE13 and Eca109 cells. Transfection of miR-18a mimetics increased cyclin D1, while transfection of miR-18a antagomir decreased D1. Moreover, miR-18a-mediated upregulation of cyclin D1 was accompanied with downregulation of PTEN, which is a direct target of miR-18a, and increase of the phosphorylation of AKT and S6K1. In addition, pharmacologic inhibition of AKT or mTOR kinases abolished the increase of cyclinD1 by miR-18a, which was accompanied with decreased phosphorylation of RbS780 and inhibition of cell proliferation. Our results demonstrated the upregulation of miR-18a promoted cell proliferation by increasing cylin D1 via regulating PTEN-PI3K-AKT-mTOR signaling axis, suggesting that small molecule inhibitors of AKT-mTOR signaling are potential agents for the treatment of ESCC patients with upregulation of miR-17-92 cluster. PMID:27291152

  10. Myeloid cell-derived reactive oxygen species externally regulate the proliferation of myeloid progenitors in emergency granulopoiesis

    OpenAIRE

    Kwak, Hyun-Jeong; Liu, Peng; Bajrami, Besnik; Xu, Yuanfu; Park, Shin-Young; Nombela-Arrieta, Cesar; Mondal, Subhanjan; Sun, Yan; Zhu, Haiyan; Chai, Li; Silberstein, Leslie E.; Cheng, Tao; Luo, Hongbo R.

    2015-01-01

    The cellular mechanisms controlling infection-induced emergency granulopoiesis are poorly defined. Here we found that reactive oxygen species (ROS) concentrations in the bone marrow (BM) were elevated during acute infection in a phagocytic NADPH oxidase-dependent manner in myeloid cells. Gr1+ myeloid cells were uniformly distributed in the BM, and all c-Kit+ progenitor cells were adjacent to Gr1+ myeloid cells. Inflammation-induced ROS production in the BM played a critical role in myeloid pr...

  11. Up-Regulation of miRNA-21 Expression Promotes Migration and Proliferation of Sca-1+ Cardiac Stem Cells in Mice.

    Science.gov (United States)

    Zhou, Qingling; Sun, Qiang; Zhang, Yongshan; Teng, Fei; Sun, Jinhui

    2016-01-01

    BACKGROUND This study, by regulating the expression level of microRNA-21 (miRNA-21) in antigen-1+ (Sca-1+) cardiac stem cells (CSCs), examined the role of miRNA-21 in migration, proliferation, and differentiation of Sca-1+ CSCs, and explored the use of miRNA-21 in treatment of heart-related diseases in mice. MATERIAL AND METHODS The CSCs of 20 healthy 2-month-old C57BL/6 mice were collected in our study. Immunomagnetic beads were used to separate and prepare pure Sca-1+ CSCs, which were further examined by flow cytometry. The samples were assigned to 4 groups: the blank group, the miRNA-21 mimic group, the miRNA-21 inhibitor group, and the negative control (NC) group. Quantitative real-time polymerase chain reaction (qRT-PCR), Transwell chamber assay, and the methyl thiazolylte-trazolium (MTT) assay were performed. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to measure the expression levels of GATA-4, MEF2c, TNI, and β-MHC differentiation-related genes. RESULTS Immunomagnetic separation results indicated that Sca-1+ CSCs accounted for more than 87.4% of CSCs. RT-PCR results also showed that the expression level of miRNA-21 of the miRNA-21 mimic group was higher than those of the other groups (all Pinhibitor group (all Pinhibitor group (all Pinhibitors influenced the gene expression levels of GATA-4, MEF2c, TNI, or β-MHC. CONCLUSIONS Our study provides evidence that up-regulation of miRNA-21 can promote migration and proliferation of Sca-1+ CSCs to enhance the capacity of Sca-1+ CSCs to repair damaged myocardium, which may pave the way for therapeutic strategies directed toward restoring miRNA-21 function for heart-related diseases. PMID:27210794

  12. Granulosa cell proliferation differentiation and its role in follicular development

    Institute of Scientific and Technical Information of China (English)

    LU Cuiling; YANG Wei; HU Zhaoyuan; LIU Yixun

    2005-01-01

    Granuiosa cells (GCs) are the most important cells in the ovary that undergo serious changes morphologically and physiologically during the processes of follicular proliferation, differentiation, ovulation, lutenization and atresia. Oocyte (OC) directs GC proliferation and differentiation, while GCs influence OC maturation. Many ovarian factors are involved in the regulation of these processes via different molecular mechanisms and signal pathways. P38MAPK can selectively regulate steroidogenesis in GCs controlled by FSH; Transcript factors LRH-1 and DAX-1 play an important role in this process; FSH induces GC prolfferation and differentiation by stimulating PCNA and StAR expression and steroidogenesis. Activated ERK1/2 signal pathway may be involved in the FSH-regulated GC proliferation and differentiation. Therefore, GC is an ideal model for studying cell proliferation, differentiation and interaction,as well as signal transduction. This review briefly summarizes the latest data in the literature, including the results achieved in our laboratory.

  13. Regulation of cell proliferation by nucleocytoplasmic dynamics of postnatal and embryonic exon-II-containing MBP isoforms

    NARCIS (Netherlands)

    Ozgen, Hande; Kahya, Nicoletta; de Jonge, Jenny C.; Smith, Graham S. T.; Harauz, George; Hoekstra, Dick; Baron, Wia

    2014-01-01

    The only known structural protein required for formation of myelin, produced by oligodendrocytes in the central nervous system, is myelin basic protein (MBP). This peripheral membrane protein has different developmentally-regulated isoforms, generated by alternative splicing. The isoforms are target

  14. Integrative Genomics Outlines a Biphasic Glucose Response and a ChREBP-RORγ Axis Regulating Proliferation in β Cells

    DEFF Research Database (Denmark)

    Schmidt, Søren Fisker; Madsen, Jesper Grud Skat; Frafjord, Kari Østerli;

    2016-01-01

    -sensing transcription factor ChREBP directly activates first wave enhancers, whereas repression and activation of second wave enhancers are indirect. By integrating motif enrichment within late-regulated enhancers with expression profiles of the associated transcription factors, we have identified multiple putative...

  15. Mechanism of Suppression on Proliferation of QGY Cell by Oxaliplatin

    Institute of Scientific and Technical Information of China (English)

    HE Song; ZUO Guo-qing; ZHANG Yan; TANG Wei-xue; LIU Chang-an

    2007-01-01

    Objective: To observe the effects of oxaliplatin(L-OHP) on proliferation of human hepatoma cell line QGY in vitro and to investigate the mechanism. Methods: The inhibition of proliferation in QGY cell was assayed by MTT-test. Morphologic changes were observed under light microscope and electronic microscope. Distribution of cell cycle and apoptosis were analyzed using flow cytometry. The expressions of cell cycle proteins and apoptosis-associated proteins were detected with immuno-histochemical technique. Results: Oxaliplatin could inhibit the proliferation of QGY cells and the inhibition depended on the exposure time and dose. The cells showed morphologic changes of the early stage of apoptosis under the light microscope: the shrunk round cells, condensed cytoplasma and pycnosis of nucleus. Apoptotic cells and apoptotic body could be found under the transmission electronic microscope. The analysis of cell cycle indicated that oxaliplatin blocked cells at S and G2/M phases and the cells of G0/Gl phase reduced. When treated with oxaliplatin for 72h, the expressions of cyclin A and Bax were up-regulated, mutant type P53, Bcl-2 and Myc were down-regulated, and Fas was not changed. Conclusion: Oxaliplatin could inhibit the proliferation of the hepatoma cell lines. Cells were blocked at S and G2/M phases. The apoptosis was related to the up-regulation of Bax and down-regulation of mutant type P53, Bcl-2 and Myc. Oxaliplatin could not induce apoptosis through the Fas pathway.

  16. MicroRNA transcriptome analysis identifies miR-365 as a novel negative regulator of cell proliferation in Zmpste24-deficient mouse embryonic fibroblasts

    International Nuclear Information System (INIS)

    Highlights: • A comprehensive miRNA transcriptome of MEFs from Zmpste24−/− and control mice. • Identification of miR-365 as a down-regulated miRNA in Zmpste24−/− MEFs. • Characterization of miR-365 as a modulator of cellular growth in part by targeting Rasd1. - Abstract: Zmpste24 is a metalloproteinase responsible for the posttranslational processing and cleavage of prelamin A into mature laminA. Zmpste24−/− mice display a range of progeroid phenotypes overlapping with mice expressing progerin, an altered version of lamin A associated with Hutchinson-Gilford progeria syndrome (HGPS). Increasing evidence has demonstrated that miRNAs contribute to the regulation of normal aging process, but their roles in progeroid disorders remain poorly understood. Here we report the miRNA transcriptomes of mouse embryonic fibroblasts (MEFs) established from wild type (WT) and Zmpste24−/− progeroid mice using a massively parallel sequencing technology. With data from 19.5 × 106 reads from WT MEFs and 16.5 × 106 reads from Zmpste24−/− MEFs, we discovered a total of 306 known miRNAs expressed in MEFs with a wide dynamic range of read counts ranging from 10 to over 1 million. A total of 8 miRNAs were found to be significantly down-regulated, with only 2 miRNAs upregulated, in Zmpste24−/− MEFs as compared to WT MEFs. Functional studies revealed that miR-365, a significantly down-regulated miRNA in Zmpste24−/− MEFs, modulates cellular growth phenotypes in MEFs. Overexpression of miR-365 in Zmpste24−/− MEFs increased cellular proliferation and decreased the percentage of SA-β-gal-positive cells, while inhibition of miR-365 function led to an increase of SA-β-gal-positive cells in WT MEFs. Furthermore, we identified Rasd1, a member of the Ras superfamily of small GTPases, as a functional target of miR-365. While expression of miR-365 suppressed Rasd1 3′ UTR luciferase-reporter activity, this effect was lost with mutations in the putative 3

  17. Cell proliferation alterations in Chlorella cells under stress conditions

    International Nuclear Information System (INIS)

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  18. Cell proliferation alterations in Chlorella cells under stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rioboo, Carmen [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); O' Connor, Jose Enrique [Laboratorio de Citomica, Unidad Mixta de Investigacion CIPF-UVEG, Centro de Investigacion Principe Felipe, Avda. Autopista del Saler, 16, 46013 Valencia (Spain); Prado, Raquel; Herrero, Concepcion [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); Cid, Angeles, E-mail: cid@udc.es [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain)

    2009-09-14

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  19. Carvacrol Alleviates Prostate Cancer Cell Proliferation, Migration, and Invasion through Regulation of PI3K/Akt and MAPK Signaling Pathways

    Science.gov (United States)

    Luo, Yun; Wu, Jie-Ying; Lu, Min-Hua; Shi, Zhi

    2016-01-01

    TRPM7 is a potential therapeutic target for treatment of prostate cancer. In this study, we investigated the effects of nonselective TRPM7 inhibitor carvacrol on cell proliferation, migration, and invasion of prostate cancer PC-3 and DU145 cells. Our results showed that carvacrol blocked TRPM7-like currents in PC-3 and DU145 cells and reduced their proliferation, migration, and invasion. Moreover, carvacrol treatment significantly decreased MMP-2, p-Akt, and p-ERK1/2 protein expression and inhibited F-actin reorganization. Furthermore, consistently, TRPM7 knockdown reduced prostate cancer cell proliferation, migration, and invasion as well. Our study suggests that carvacrol may have therapeutic potential for the treatment of prostate cancer through its inhibition of TRPM7 channels and suppression of PI3K/Akt and MAPK signaling pathways. PMID:27803760

  20. CpG methyltransferase induced down-regulation of claudin-7,-8 and its effects on proliferation and apoptosis of human colorectal cancer HT-29 cells

    Institute of Scientific and Technical Information of China (English)

    王文辉

    2013-01-01

    Objective To explore the regulatory effect of CpG methyltransferase (M.SssI) on expression of claudin-7and claudin-8,promoting apoptosis and inhibiting proliferation of human colorectal cancer HT-29 cells.Methods HT-29 cells were treated with M.SssI (50 U/ml) for

  1. Peroxiredoxins, oxidative stress, and cell proliferation.

    Science.gov (United States)

    Immenschuh, Stephan; Baumgart-Vogt, Eveline

    2005-01-01

    Peroxiredoxins (Prxs) are a family of multifunctional antioxidant thioredoxin-dependent peroxidases that have been identified in a large variety of organisms. The major functions of Prxs comprise cellular protection against oxidative stress, modulation of intracellular signaling cascades that apply hydrogen peroxide as a second messenger molecule, and regulation of cell proliferation. In the present review, we discuss pertinent findings on the protein structure, the cell- and tissue-specific distribution, as well as the subcellular localization of Prxs. A particular emphasis is put on Prx I, which is the most abundant and ubiquitously distributed member of the mammalian Prxs. Major transcriptional and posttranslational regulatory mechanisms and signaling pathways that control Prx gene expression and activity are summarized. The interaction of Prx I with the oncogene products c-Abl and c-Myc and the regulatory role of Prx I for cell proliferation and apoptosis are highlighted. Recent findings on phenotypical alterations of mouse models with targeted disruptions of Prx genes are discussed, confirming the physiological functions of Prxs for antioxidant cell and tissue protection along with an important role as tumor suppressors.

  2. Differential regulation of LncRNA-SARCC suppresses VHL-mutant RCC cell proliferation yet promotes VHL-normal RCC cell proliferation via modulating androgen receptor/HIF-2α/C-MYC axis under hypoxia.

    Science.gov (United States)

    Zhai, W; Sun, Y; Jiang, M; Wang, M; Gasiewicz, T A; Zheng, J; Chang, C

    2016-09-15

    It is well established that hypoxia contributes to tumor progression in a hypoxia inducible factor-2α (HIF-2α)-dependent manner in renal cell carcinoma (RCC), yet the role of long noncoding RNAs (LncRNAs) involved in hypoxia-mediated RCC progression remains unclear. Here we demonstrate that LncRNA-SARCC (Suppressing Androgen Receptor in Renal Cell Carcinoma) is differentially regulated by hypoxia in a von Hippel-Lindau (VHL)-dependent manner both in RCC cell culture and clinical specimens. LncRNA-SARCC can suppress hypoxic cell cycle progression in the VHL-mutant RCC cells while derepress it in the VHL-restored RCC cells. Mechanism dissection reveals that LncRNA-SARCC can post-transcriptionally regulate androgen receptor (AR) by physically binding and destablizing AR protein to suppress AR/HIF-2α/C-MYC signals. In return, HIF-2α can transcriptionally regulate the LncRNA-SARCC expression via binding to hypoxia-responsive elements on the promoter of LncRNA-SARCC. The negative feedback modulation between LncRNA-SARCC/AR complex and HIF-2α signaling may then lead to differentially modulated RCC progression in a VHL-dependent manner. Together, these results may provide us a new therapeutic approach via targeting this newly identified signal from LncRNA-SARCC to AR-mediated HIF-2α/C-MYC signals against RCC progression.

  3. Positive and negative regulation of cell proliferation by E2F-1: influence of protein level and human papillomavirus oncoproteins

    DEFF Research Database (Denmark)

    Melillo, R M; Helin, K; Lowy, D R;

    1994-01-01

    E2F-1 is a member of a family of transcription factors implicated in the activation of genes required for the progression through the S phase of the cell cycle. We have examined the biological activities of E2F-1 with short-term colony-forming assays and long-term immortalization assays. High lev...

  4. Nicotine promotes proliferation of human nasopharyngeal carcinoma cells by regulating α7AChR, ERK, HIF-1α and VEGF/PEDF signaling.

    Directory of Open Access Journals (Sweden)

    Dingbo Shi

    Full Text Available Nicotine, the major component in cigarette smoke, can promote tumor growth and angiogenesis, but the precise mechanisms involved remain largely unknown. Here, we investigated the mechanism of action of nicotine in human nasopharyngeal carcinoma (NPC cells. Nicotine significantly promoted cell proliferation in a dose and time-dependent manner in human NPC cells. The mechanism studies showed that the observed stimulation of proliferation was accompanied by the nicotine-mediated simultaneous modulation of α7AChR, HIF-1α, ERK and VEGF/PEDF signaling. Treatment of NPC cells with nicotine markedly upregulated the expression of α7AChR and HIF-1α proteins. Transfection with a α7AChR or HIF-1α-specific siRNA or a α7AChR-selective inhibitor significantly attenuated the nicotine-mediated promotion of NPC cell proliferation. Nicotine also promoted the phosphorylation of ERK1/2 but not JNK and p38 proteins, thereby induced the activation of ERK/MAPK signaling pathway. Pretreatment with an ERK-selective inhibitor effectively reduced the nicotine-induced proliferation of NPC cells. Moreover, nicotine upregulated the expression of VEGF but suppressed the expression of PEDF at mRNA and protein levels, leading to a significant increase of the ratio of VEGF/PEDF in NPC cells. Pretreatment with a α7AChR or ERK-selective inhibitor or transfection with a HIF-1α-specific siRNA in NPC cells significantly inhibited the nicotine-induced HIF-1α expression and VEGF/PEDF ratio. These results therefore indicate that nicotine promotes proliferation of human NPC cells in vitro through simultaneous modulation of α7AChR, HIF-1α, ERK and VEGF/PEDF signaling and suggest that the related molecules such as HIF-1α might be the potential therapeutic targets for tobacco-associated diseases such as nasopharyngeal carcinomas.

  5. Nkx6.1 regulates islet β-cell proliferation via Nr4a1 and Nr4a3 nuclear receptors.

    Science.gov (United States)

    Tessem, Jeffery S; Moss, Larry G; Chao, Lily C; Arlotto, Michelle; Lu, Danhong; Jensen, Mette V; Stephens, Samuel B; Tontonoz, Peter; Hohmeier, Hans E; Newgard, Christopher B

    2014-04-01

    Loss of functional β-cell mass is a hallmark of type 1 and type 2 diabetes, and methods for restoring these cells are needed. We have previously reported that overexpression of the homeodomain transcription factor NK6 homeobox 1 (Nkx6.1) in rat pancreatic islets induces β-cell proliferation and enhances glucose-stimulated insulin secretion, but the pathway by which Nkx6.1 activates β-cell expansion has not been defined. Here, we demonstrate that Nkx6.1 induces expression of the nuclear receptor subfamily 4, group A, members 1 and 3 (Nr4a1 and Nr4a3) orphan nuclear receptors, and that these factors are both necessary and sufficient for Nkx6.1-mediated β-cell proliferation. Consistent with this finding, global knockout of Nr4a1 results in a decrease in β-cell area in neonatal and young mice. Overexpression of Nkx6.1 and the Nr4a receptors results in increased expression of key cell cycle inducers E2F transcription factor 1 and cyclin E1. Furthermore, Nkx6.1 and Nr4a receptors induce components of the anaphase-promoting complex, including ubiquitin-conjugating enzyme E2C, resulting in degradation of the cell cycle inhibitor p21. These studies identify a unique bipartite pathway for activation of β-cell proliferation, suggesting several unique targets for expansion of functional β-cell mass.

  6. Chimeric-transgenic mice represent a powerful tool for studying how the proliferation and differentiation programs of intestinal epithelial cell lineages are regulated.

    OpenAIRE

    Hermiston, M L; Green, R. P.; Gordon, J I

    1993-01-01

    An in vivo system has been developed for examining the effects of wild-type or mutant proteins on cell fate determination in the mouse intestinal epithelium or on the proliferation and differentiation programs of its component epithelial lineages. This system takes advantage of the fact that at the conclusion of gut morphogenesis, each intestinal crypt is composed of a monoclonal population of cells descended from a single active multipotent stem cell, each villus is supplied by several monoc...

  7. Insulin-like growth factor binding protein-3 is required for the regulation of rat oval cell proliferation and differentiation in the 2AAF/PHX model

    OpenAIRE

    Steiger-Luther, Nicole C; Darwiche, Houda; Oh, Seh-Hoon; Williams, Jennifer M.; PETERSEN, BRYON E.

    2010-01-01

    Oval cell-mediated liver regeneration is a highly complex process that involves the coordination of several signaling factors, chemokines and cytokines to allow for proper maintenance of the liver architecture. When hepatocyte proliferation is inhibited, an hepatic stem cell population, often referred to as “oval cells”, is activated to aid in liver regeneration. The function of insulin-like growth factor binding protein-3 (IGFBP-3) during this process of oval cell activation is of particular...

  8. EBV Nuclear Antigen 3C Mediates Regulation of E2F6 to Inhibit E2F1 Transcription and Promote Cell Proliferation.

    Science.gov (United States)

    Pei, Yonggang; Banerjee, Shuvomoy; Sun, Zhiguo; Jha, Hem Chandra; Saha, Abhik; Robertson, Erle S

    2016-08-01

    Epstein-Barr virus (EBV) is considered a ubiquitous herpesvirus with the ability to cause latent infection in humans worldwide. EBV-association is evidently linked to different types of human malignancies, mainly of epithelial and lymphoid origin. Of interest is the EBV nuclear antigen 3C (EBNA3C) which is critical for EBV-mediated immortalization. Recently, EBNA3C was shown to bind the E2F1 transcription regulator. The E2F transcription factors have crucial roles in various cellular functions, including cell cycle, DNA replication, DNA repair, cell mitosis, and cell fate. Specifically, E2F6, one of the unique E2F family members, is known to be a pRb-independent transcription repressor of E2F-target genes. In our current study, we explore the role of EBNA3C in regulating E2F6 activities. We observed that EBNA3C plays an important role in inducing E2F6 expression in LCLs. Our study also shows that EBNA3C physically interacts with E2F6 at its amino and carboxy terminal domains and they form a protein complex in human cells. In addition, EBNA3C stabilizes the E2F6 protein and is co-localized in the nucleus. We also demonstrated that both EBNA3C and E2F6 contribute to reduction in E2F1 transcriptional activity. Moreover, E2F1 forms a protein complex with EBNA3C and E2F6, and EBNA3C competes with E2F1 for E2F6 binding. E2F6 is also recruited by EBNA3C to the E2F1 promoter, which is critical for EBNA3C-mediated cell proliferation. These results demonstrate a critical role for E2F family members in EBV-induced malignancies, and provide new insights for targeting E2F transcription factors in EBV-associated cancers as potential therapeutic intervention strategies.

  9. EBV Nuclear Antigen 3C Mediates Regulation of E2F6 to Inhibit E2F1 Transcription and Promote Cell Proliferation.

    Science.gov (United States)

    Pei, Yonggang; Banerjee, Shuvomoy; Sun, Zhiguo; Jha, Hem Chandra; Saha, Abhik; Robertson, Erle S

    2016-08-01

    Epstein-Barr virus (EBV) is considered a ubiquitous herpesvirus with the ability to cause latent infection in humans worldwide. EBV-association is evidently linked to different types of human malignancies, mainly of epithelial and lymphoid origin. Of interest is the EBV nuclear antigen 3C (EBNA3C) which is critical for EBV-mediated immortalization. Recently, EBNA3C was shown to bind the E2F1 transcription regulator. The E2F transcription factors have crucial roles in various cellular functions, including cell cycle, DNA replication, DNA repair, cell mitosis, and cell fate. Specifically, E2F6, one of the unique E2F family members, is known to be a pRb-independent transcription repressor of E2F-target genes. In our current study, we explore the role of EBNA3C in regulating E2F6 activities. We observed that EBNA3C plays an important role in inducing E2F6 expression in LCLs. Our study also shows that EBNA3C physically interacts with E2F6 at its amino and carboxy terminal domains and they form a protein complex in human cells. In addition, EBNA3C stabilizes the E2F6 protein and is co-localized in the nucleus. We also demonstrated that both EBNA3C and E2F6 contribute to reduction in E2F1 transcriptional activity. Moreover, E2F1 forms a protein complex with EBNA3C and E2F6, and EBNA3C competes with E2F1 for E2F6 binding. E2F6 is also recruited by EBNA3C to the E2F1 promoter, which is critical for EBNA3C-mediated cell proliferation. These results demonstrate a critical role for E2F family members in EBV-induced malignancies, and provide new insights for targeting E2F transcription factors in EBV-associated cancers as potential therapeutic intervention strategies. PMID:27548379

  10. Conjugated linoleic acid isomers and their precursor fatty acids regulate peroxisome proliferator-activated receptor subtypes and major peroxisome proliferator responsive element-bearing target genes in HepG2 cell model*

    OpenAIRE

    Benjamin, Sailas; Flotho, Silke; Börchers, Torsten; Spener, Friedrich

    2013-01-01

    The purpose of this study was to examine the induction profiles (as judged by quantitative reverse transcription polymerase chain reaction (qRT-PCR)) of peroxisome proliferator-activated receptor (PPAR) α, β, γ subtypes and major PPAR-target genes bearing a functional peroxisome proliferator responsive element (PPRE) in HepG2 cell model upon feeding with cis-9,trans-11-octadecadienoic acid (9-CLA) or trans-10,cis-12-octadecadienoic acid (10-CLA) or their precursor fatty acids (FAs). HepG2 cel...

  11. iASPP is over-expressed in human non-small cell lung cancer and regulates the proliferation of lung cancer cells through a p53 associated pathway

    International Nuclear Information System (INIS)

    iASPP is a key inhibitor of tumour suppressor p53 and is found to be up-regulated in certain malignant conditions. The present study investigated the expression of iASPP in clinical lung cancer, a leading cancer type in the world, and the biological impact of this molecule on lung cancer cells. iASPP protein levels in lung cancer tissues were evaluated using an immunohistochemical method. In vitro, iASPP gene expression was suppressed with a lentvirus-mediated shRNA method and the biological impact after knocking down iASSP on lung cancer cell lines was investigated in connection with the p53 expression status. We showed here that the expression of iASPP was significantly higher in lung cancer tissues compared with the adjacent normal tissues. iASPP shRNA treatment resulted in a down-regulation of iASPP in lung cancer cells. There was a subsequent reduction of cell proliferation of the two lung tumour cell lines A459 and 95D both of which had wild-type p53 expression. In contrast, reduction of iASPP in H1229 cells, a cell with little p53 expression, had no impact on its growth rate. iASPP regulates the proliferation and motility of lung cancer cells. This effect is intimately associated with the p53 pathway. Together with the pattern of the over-expression in clinical lung cancers, it is concluded that iASPP plays an pivotal role in the progression of lung cancer and is a potential target for lung cancer therapy

  12. Igf2-H19, an imprinted tandem gene, is an important regulator of embryonic development, a guardian of proliferation of adult pluripotent stem cells, a regulator of longevity, and a ‘passkey’ to cancerogenesis

    Directory of Open Access Journals (Sweden)

    Mariusz Z. Ratajczak

    2012-07-01

    Full Text Available The insulin-like growth factor-2 (Igf2-H19 locus encodes important paternally imprinted genes that govern normal embryonic development. While Igf-2 encodes IGF2, which is an autocrine/paracrine mitogen,  transcription of H19 gives rise to non-coding mRNA that is a precursor of several microRNAs (miRNAs that negatively affect cell proliferation. The proper imprinting of a differentially methylated region (DMR within this locus, with methylation of the paternal chromosome and a lack of methylation on the maternal chromosome, regulates expression of both of these genes so that Igf2 is transcribed only from the paternal chromosome and H19 only from the maternal chromosome. There is growing evidence that this ‘Yin-Yang’ locus regulates embryonic development. Furthermore, recent evidence indicates that erasure of imprinting (hypomethylation of the Igf2-H19 locus on both chromosomes, which leads to downregulation of Igf2 and upregulation of H19 expression, plays an important role in regulating quiescence of pluripotent stem cells in adult organisms, and may be involved in the regulation of lifespan. In contrast, hypermethylation of this locus on both chromosomes (loss of imprinting results in Igf2 overexpression and is observed in several malignancies. In this review, we will discuss the biological consequences of changes in Igf2-H19 expression.

  13. Quantitative analysis of in vivo cell proliferation.

    Science.gov (United States)

    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

  14. Molecular structure and biological function of proliferating cell nuclear antigen

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote.As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

  15. Nicotine as a mitogenic stimulus for pancreatic acinar cell proliferation

    Institute of Scientific and Technical Information of China (English)

    Parimal Chowdhury; Kodetthoor B Udupa

    2006-01-01

    Cell proliferation is an important process in life for growth of normal and cancer cells. The signal transduction pathways activated during this process are strictly regulated. This editorial focuses on the role of nicotine,a mitogen, in the induction of signaling pathways resulting in proliferation of pancreatic tumor cells and compares these events with those in normal acinar cells isolated from the rat pancreas. The data shows striking similarities between these two cellular systems.In addition, the editorial reviews very recent literature of the contribution of MAPK signaling in cell lines associated with human diseases. A prospective cellular model of nicotine induced activation of MAPK cascade is presented.

  16. Peroxisomes in Different Skeletal Cell Types during Intramembranous and Endochondral Ossification and Their Regulation during Osteoblast Differentiation by Distinct Peroxisome Proliferator-Activated Receptors.

    Directory of Open Access Journals (Sweden)

    Guofeng Qian

    Full Text Available Ossification defects leading to craniofacial dysmorphism or rhizomelia are typical phenotypes in patients and corresponding knockout mouse models with distinct peroxisomal disorders. Despite these obvious skeletal pathologies, to date no careful analysis exists on the distribution and function of peroxisomes in skeletal tissues and their alterations during ossification. Therefore, we analyzed the peroxisomal compartment in different cell types of mouse cartilage and bone as well as in primary cultures of calvarial osteoblasts. The peroxisome number and metabolism strongly increased in chondrocytes during endochondral ossification from the reserve to the hypertrophic zone, whereas in bone, metabolically active osteoblasts contained a higher numerical abundance of this organelle than osteocytes. The high abundance of peroxisomes in these skeletal cell types is reflected by high levels of Pex11β gene expression. During culture, calvarial pre-osteoblasts differentiated into secretory osteoblasts accompanied by peroxisome proliferation and increased levels of peroxisomal genes and proteins. Since many peroxisomal genes contain a PPAR-responsive element, we analyzed the gene expression of PPARɑ/ß/ɣ in calvarial osteoblasts and MC3T3-E1 cells, revealing higher levels for PPARß than for PPARɑ and PPARɣ. Treatment with different PPAR agonists and antagonists not only changed the peroxisomal compartment and associated gene expression, but also induced complex alterations of the gene expression patterns of the other PPAR family members. Studies in M3CT3-E1 cells showed that the PPARß agonist GW0742 activated the PPRE-mediated luciferase expression and up-regulated peroxisomal gene transcription (Pex11, Pex13, Pex14, Acox1 and Cat, whereas the PPARß antagonist GSK0660 led to repression of the PPRE and a decrease of the corresponding mRNA levels. In the same way, treatment of calvarial osteoblasts with GW0742 increased in peroxisome number and

  17. Expression of cell cycle regulator p57kip2, cyclinE protein and proliferating cell nuclear antigen in human pancreatic cancer: An immunohistochemical study

    Institute of Scientific and Technical Information of China (English)

    Hui Yue; Hui-Yong Jiang

    2005-01-01

    AIM: To investigate the effects of p57kip2, cyclinE protein and proliferating cell nuclear antigen (PCNA) on occurrence and progression of human pancreatic cancer.METHODS: The expression of p57kip2, cyclinE protein and PCNA in tumor tissues and adjacent tissues from 32patients with pancreatic cancer was detected by SP immunohistochemical technique.RESULTS: The positive expression rate of p57kip2 protein in tumor tissues was 46.9%, which was lower than that in adjacent pancreatic tissues (x2 = 5.317, P<0.05). P57kip2protein positive expression remarkably correlated with tumor cell differentiation (P<0.05), but not with lymph node metastasis (P>0.05). The positive expression rate of cyclinE protein in tumor tissues was 68.8%, which was higher than that in adjacent pancreatic tissues (x2 = 4.063,P<0.05). CyclinE protein positive expression significantly correlated with tumor cell differentiation and lymph node metastasis (P<0.05). The positive expression rate of PCNA in the tumor tissues was 71.9%, which was higher than that in adjacent pancreatic tissues (x2 = 5.189, P<0.05).PCNA positive expression remarkably correlated with tumor cell differentiation and lymph node metastasis (P<0.05).CONCLUSION: The decreased expression of p57kip2 and/or overexpression of cyclinE protein and PCNA may contribute to the occurrence and progression of pancreatic cancer.p57kip2, cyclinE protein, and PCNA play an important role in occurrence and progression of pancreatic cancer.

  18. 17β-Estradiol regulates cell proliferation, colony formation, migration, invasion and promotes apoptosis by upregulating miR-9 and thus degrades MALAT-1 in osteosarcoma cell MG-63 in an estrogen receptor-independent manner

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Dengfeng; Yang, Hui; Lin, Jing; Teng, Yi; Jiang, Yingying; Chen, Jiao; Li, Yu, E-mail: yuli_scu@163.com

    2015-02-20

    In bone, different concentration of estrogen leads to various of physiological processes in osteoblast, such as the proliferation, migration, and apoptosis in an estrogen receptor-dependent manner. But little was known about the estrogen effects on osteosarcoma (OS). In this study, OS cell MG-63 was treated with low (1 nM) or high (100 nM) dose of 17β-Estradiol (E2) with the presence or absence of estrogen receptor α (ERα), for evaluating the E2 effects on proliferation, migration, invasion, colony formation and apoptosis. Consistent with a previous study, high dose of E2 treatment dramatically downregulated expressing level of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1). The observation of upregulation of miR-9 after a high dose of E2 treatment indicated the cause of MALAT-1 reduction. Downregulation of MALAT-1 promoted the combination of SFPQ/PTBP2 complex. It was also observed that the proliferation, migration, invasion, colony formation and apoptosis of OS cells were remarkably affected by high dose of E2 treatment, but not by low dose, in an ERα independent manner. Furthermore, the abolishment of the effects on these physiological processes caused by ectopic expression of miR-9 ASOs suggested the necessity of miR-9 in MALAT-1 regulation. Here we found that the high dose of E2 treatment upregulated miR-9 thus posttranscriptionally regulated MALAT-1 RNA level in OS cells, and then the downregulation of MALAT-1 inhibited cell proliferation, migration, invasion and epithelial–mesenchymal transition (EMT) processes in the E2-dose dependent and ER-independent ways. - Highlights: • E2 affects osteosarcoma cell MG-63 in an Estrogen receptor-independent way. • High dose of E2 treatment upregulates miR-9 which target to MALAT-1 RNA. • Upregulated miR-9 degrades MALAT-1 and thus affects combination of SFPQ/PTBP2. • E2 treatment block cell proliferation, colony formation, mobility, and enhance apoptosis.

  19. 17β-Estradiol regulates cell proliferation, colony formation, migration, invasion and promotes apoptosis by upregulating miR-9 and thus degrades MALAT-1 in osteosarcoma cell MG-63 in an estrogen receptor-independent manner

    International Nuclear Information System (INIS)

    In bone, different concentration of estrogen leads to various of physiological processes in osteoblast, such as the proliferation, migration, and apoptosis in an estrogen receptor-dependent manner. But little was known about the estrogen effects on osteosarcoma (OS). In this study, OS cell MG-63 was treated with low (1 nM) or high (100 nM) dose of 17β-Estradiol (E2) with the presence or absence of estrogen receptor α (ERα), for evaluating the E2 effects on proliferation, migration, invasion, colony formation and apoptosis. Consistent with a previous study, high dose of E2 treatment dramatically downregulated expressing level of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1). The observation of upregulation of miR-9 after a high dose of E2 treatment indicated the cause of MALAT-1 reduction. Downregulation of MALAT-1 promoted the combination of SFPQ/PTBP2 complex. It was also observed that the proliferation, migration, invasion, colony formation and apoptosis of OS cells were remarkably affected by high dose of E2 treatment, but not by low dose, in an ERα independent manner. Furthermore, the abolishment of the effects on these physiological processes caused by ectopic expression of miR-9 ASOs suggested the necessity of miR-9 in MALAT-1 regulation. Here we found that the high dose of E2 treatment upregulated miR-9 thus posttranscriptionally regulated MALAT-1 RNA level in OS cells, and then the downregulation of MALAT-1 inhibited cell proliferation, migration, invasion and epithelial–mesenchymal transition (EMT) processes in the E2-dose dependent and ER-independent ways. - Highlights: • E2 affects osteosarcoma cell MG-63 in an Estrogen receptor-independent way. • High dose of E2 treatment upregulates miR-9 which target to MALAT-1 RNA. • Upregulated miR-9 degrades MALAT-1 and thus affects combination of SFPQ/PTBP2. • E2 treatment block cell proliferation, colony formation, mobility, and enhance apoptosis

  20. PEROXISOME PROLIFERATOR-ACTIVATED RECEPTORα (PPARα) AGONISTS DIFFERENTIALLY REGULATE INHIBITOR OF DNA BINDING (ID2) EXPRESSION IN RODENTS AND HUMAN CELLS

    Science.gov (United States)

    Abstract Inhibitor of DNA binding (Id2) is a member of the helix-loop-helix (HLH) transcription factor family whose members play important roles in cell differentiation and proliferation. Id2 has been linked to the development of cardiovascular diseases since thiazolidinediones,...

  1. EGFR signaling regulates the proliferation of Drosophila adult midgut progenitors

    OpenAIRE

    Jiang, Huaqi; Edgar, Bruce A.

    2009-01-01

    In holometabolous insects, the adult appendages and internal organs form anew from larval progenitor cells during metamorphosis. As described here, the adult Drosophila midgut, including intestinal stem cells (ISCs), develops from adult midgut progenitor cells (AMPs) that proliferate during larval development in two phases. Dividing AMPs first disperse, but later proliferate within distinct islands, forming large cell clusters that eventually fuse during metamorphosis ...

  2. Natriuretic peptide receptor-3 underpins the disparate regulation of endothelial and vascular smooth muscle cell proliferation by C-type natriuretic peptide

    OpenAIRE

    Khambata, Rayomand S.; Panayiotou, Catherine M; Hobbs, Adrian J

    2011-01-01

    BACKGROUND AND PURPOSE C-type natriuretic peptide (CNP) is an endothelium-derived vasorelaxant, exerting anti-atherogenic actions in the vasculature and salvaging the myocardium from ischaemic injury. The cytoprotective effects of CNP are mediated in part via the Gi-coupled natriuretic peptide receptor (NPR)3. As GPCRs are well-known to control cell proliferation, we investigated if NPR3 activation underlies effects of CNP on endothelial and vascular smooth muscle cell mitogenesis. EXPERIMENT...

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

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yang; Pang, Xiaoyan; Dong, Mei; Wen, Fang, E-mail: wenfang64@hotmail.com; Zhang, Yi, E-mail: syzi960@yahoo.com

    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.

  4. 线粒体在支气管平滑肌细胞增殖中的调控作用%Regulation Effects of Mitochondria to Bronchoscopy Smooth Muscle Cell Proliferation

    Institute of Scientific and Technical Information of China (English)

    张允健

    2012-01-01

    慢性阻塞性肺疾病(COPD)是一种常见的慢性疾病,支气管平滑肌细胞(BSMC)增殖是COPD重要的病理特征之一.氧化应激可刺激多种细胞增殖,亦可能刺激支气管平滑肌细胞增殖,进而导致COPD的发生和加重.在氧化应激状态下,线粒体通过调节线粒体融合蛋白2表达调节BSMC的增殖、分化、凋亡.现就线粒体在BSMC增殖中发挥的调控作用进行综述.%Chronic obstructive pulmonary disease(COPD )is a kind of common chronic disease, bronchus smooth muscle cells( BSMC )proliferation is one oi the important pathological characteristics. Oxidative stress can stimulate many kinds oi cells proliferation, oxidative stress may as well stimulate bronchus smooth muscle cells proliferation, and then induce COPD generation and aggravation. In the state of oxidative stress, mitochondria regulates the piolifeiation, differentiation, apoptosis of BSMCs through regulate mitofusin2( Mfn2 ) expression. Here is to make a review on the mitochondria role in the regulation of BSMC proliferation.

  5. Regulation of mitogen-stimulated human T-cell proliferation, interleukin-2 production, and interleukin-2 receptor expression by protein kinase C inhibitor, H-7

    Energy Technology Data Exchange (ETDEWEB)

    Atluru, D.; Polam, S.; Atluru, S. (Kansas State Univ., Manhattan (United States)); Woloschak, G.E. (Argonne National Lab., IL (United States))

    1990-01-01

    Recently published reports suggest that the activation of protein kinase C (PKC) plays an important role in the activation pathway of many cell types. In this study, the authors examined the role of PKC in human T-cell proliferation, IL-2 production, and IL-2R expression, when cultured with the mitogen PHA, the PKC inhibitor H-7, and H-7 control HA1004. H-7 inhibited the PHA-simulated ({sup 3}H)thymidine uptake, IL-2production, and IL-2R expression in a dose-related manner. Further, they found H-7 inhibited T-cell proliferation, IL-2 production, and IL-2mRNA from PHA plus PMA-stimulated cultures. They also found that H-7 inhibited the early-stage activation of PHA-stimulated cells. The presence of exogenous purified human IL-2 or rIL-4 partly reversed the immunosuppression caused by H-7. In contrast, HA1004 had no effect on cell proliferation, IL-2 production, or IL-2R expression. The results demonstrate that PKC activation is one major pathway through which T-cells become activated.

  6. RelA-Induced Interferon Response Negatively Regulates Proliferation

    OpenAIRE

    Bose S Kochupurakkal; Wang, Zhigang C.; Tony Hua; Culhane, Aedin C.; Scott J Rodig; Koraljka Rajkovic-Molek; Jean-Bernard Lazaro; Richardson, Andrea L.; Biswas, Debajit K.; J Dirk Iglehart

    2015-01-01

    Both oncogenic and tumor-suppressor activities are attributed to the Nuclear Factor kappa B (NF-kB) pathway. Moreover, NF-kB may positively or negatively regulate proliferation. The molecular determinants of these opposing roles of NF-kB are unclear. Using primary human mammary epithelial cells (HMEC) as a model, we show that increased RelA levels and consequent increase in basal transcriptional activity of RelA induces IRF1, a target gene. Induced IRF1 upregulates STAT1 and IRF7, and in cons...

  7. MicroRNA transcriptome analysis identifies miR-365 as a novel negative regulator of cell proliferation in Zmpste24-deficient mouse embryonic fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Xing-dong [Institute of Aging Research, Guangdong Medical College, Xin Cheng Avenue 1#, Songshan Lake, Dongguan, Guangdong 523808 (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical College, Zhanjiang 524023 (China); Key Laboratory for Medical Molecular Diagnostics of Guangdong Province, Dongguan 523808 (China); Institute of Laboratory Medicine, Guangdong Medical College, Dongguan, Guangdong 523808 (China); Jung, Hwa Jin [Departments of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461 (United States); Gombar, Saurabh [Departments of Systems Biology, Albert Einstein College of Medicine, Bronx, NY 10461 (United States); Park, Jung Yoon [Departments of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461 (United States); Zhang, Chun-long; Zheng, Huiling [Institute of Aging Research, Guangdong Medical College, Xin Cheng Avenue 1#, Songshan Lake, Dongguan, Guangdong 523808 (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical College, Zhanjiang 524023 (China); Key Laboratory for Medical Molecular Diagnostics of Guangdong Province, Dongguan 523808 (China); Ruan, Jie; Li, Jiang-bin [Institute of Aging Research, Guangdong Medical College, Xin Cheng Avenue 1#, Songshan Lake, Dongguan, Guangdong 523808 (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical College, Zhanjiang 524023 (China); Key Laboratory for Medical Molecular Diagnostics of Guangdong Province, Dongguan 523808 (China); Institute of Laboratory Medicine, Guangdong Medical College, Dongguan, Guangdong 523808 (China); Kaeberlein, Matt [Institute of Aging Research, Guangdong Medical College, Xin Cheng Avenue 1#, Songshan Lake, Dongguan, Guangdong 523808 (China); Department of Pathology, University of Washington, Seattle, WA 98195 (United States); and others

    2015-07-15

    Highlights: • A comprehensive miRNA transcriptome of MEFs from Zmpste24{sup −/−} and control mice. • Identification of miR-365 as a down-regulated miRNA in Zmpste24{sup −/−} MEFs. • Characterization of miR-365 as a modulator of cellular growth in part by targeting Rasd1. - Abstract: Zmpste24 is a metalloproteinase responsible for the posttranslational processing and cleavage of prelamin A into mature laminA. Zmpste24{sup −/−} mice display a range of progeroid phenotypes overlapping with mice expressing progerin, an altered version of lamin A associated with Hutchinson-Gilford progeria syndrome (HGPS). Increasing evidence has demonstrated that miRNAs contribute to the regulation of normal aging process, but their roles in progeroid disorders remain poorly understood. Here we report the miRNA transcriptomes of mouse embryonic fibroblasts (MEFs) established from wild type (WT) and Zmpste24{sup −/−} progeroid mice using a massively parallel sequencing technology. With data from 19.5 × 10{sup 6} reads from WT MEFs and 16.5 × 10{sup 6} reads from Zmpste24{sup −/−} MEFs, we discovered a total of 306 known miRNAs expressed in MEFs with a wide dynamic range of read counts ranging from 10 to over 1 million. A total of 8 miRNAs were found to be significantly down-regulated, with only 2 miRNAs upregulated, in Zmpste24{sup −/−} MEFs as compared to WT MEFs. Functional studies revealed that miR-365, a significantly down-regulated miRNA in Zmpste24{sup −/−} MEFs, modulates cellular growth phenotypes in MEFs. Overexpression of miR-365 in Zmpste24{sup −/−} MEFs increased cellular proliferation and decreased the percentage of SA-β-gal-positive cells, while inhibition of miR-365 function led to an increase of SA-β-gal-positive cells in WT MEFs. Furthermore, we identified Rasd1, a member of the Ras superfamily of small GTPases, as a functional target of miR-365. While expression of miR-365 suppressed Rasd1 3′ UTR luciferase-reporter activity

  8. In vivo regulation of colonic cell proliferation, differentiation, apoptosis, and P27Kip1 by dietary fish oil and butyrate in rats.

    Science.gov (United States)

    Hong, Mee Young; Turner, Nancy D; Murphy, Mary E; Carroll, Raymond J; Chapkin, Robert S; Lupton, Joanne R

    2015-11-01

    We have shown that dietary fish oil is protective against experimentally induced colon cancer, and the protective effect is enhanced by coadministration of pectin. However, the underlying mechanisms have not been fully elucidated. We hypothesized that fish oil with butyrate, a pectin fermentation product, protects against colon cancer initiation by decreasing cell proliferation and increasing differentiation and apoptosis through a p27(Kip1)-mediated mechanism. Rats were provided diets of corn or fish oil, with/without butyrate, and terminated 12, 24, or 48 hours after azoxymethane (AOM) injection. Proliferation (Ki-67), differentiation (Dolichos Biflorus Agglutinin), apoptosis (TUNEL), and p27(Kip1) (cell-cycle mediator) were measured in the same cell within crypts in order to examine the coordination of cell cycle as a function of diet. DNA damage (N(7)-methylguanine) was determined by quantitative IHC analysis. Dietary fish oil decreased DNA damage by 19% (P = 0.001) and proliferation by 50% (P = 0.003) and increased differentiation by 56% (P = 0.039) compared with corn oil. When combined with butyrate, fish oil enhanced apoptosis 24 hours after AOM injection compared with a corn oil/butyrate diet (P = 0.039). There was an inverse relationship between crypt height and apoptosis in the fish oil/butyrate group (r = -0.53, P = 0.040). The corn oil/butyrate group showed a positive correlation between p27(Kip1) expression and proliferation (r = 0.61, P = 0.035). These results indicate the in vivo effect of butyrate on apoptosis and proliferation is dependent on dietary lipid source. These results demonstrate the presence of an early coordinated colonocyte response by which fish oil and butyrate protects against colon tumorigenesis.

  9. Inhibition of janus kinase 2 by compound AG490 suppresses the proliferation of MDA-MB-231 cells via up-regulating SARI (suppressor of AP-1, regulated by IFN)

    OpenAIRE

    Yan-xia Zhang; Li Yan; Guang-yu Liu; Wen-jun Chen; Wei-hong Gong; Jin-ming Yu

    2015-01-01

    Objective(s): The Janus kinase-signal transducers and activators of transcription signaling pathway (JAK/STAT pathway) play an important role in proliferation of breast cancer cells. Previous data showed that inhibition of STAT3 suppresses the growth of breast cancer cells, but the associated mechanisms are not well understood. This study aims to investigate the effect and associated mechanisms of JAK/STAT pathway inhibitor AG490 on proliferation and suppression of breast cancer cells. Mat...

  10. Monovalent ions control proliferation of Ehrlich Lettre ascites cells

    DEFF Research Database (Denmark)

    Klausen, Thomas Kjaer; Preisler, Sarah; Pedersen, Stine Helene Falsig;

    2010-01-01

    with the pH-sensitive dye BCECF, substitution of Na+ was observed to upregulate the activity of the Na+/H+ exchanger NHE1 as well as of Na+-independent acid extrusion mechanisms, facilitating intracellular pH (pH(i)) recovery after acid loading and increasing pH(i). Results using the potential sensitive dye...... effect. Western blots showed reduced chloride intracellular channel CLIC1 and chloride channel ClC-2 expression in the plasma membrane in S compared with G(1). Our results suggest that Na+ regulates ELA cell proliferation by regulating intracellular pH while Cl(-) may regulate proliferation by fine...

  11. The MUC4 membrane-bound mucin regulates esophageal cancer cell proliferation and migration properties: Implication for S100A4 protein

    Energy Technology Data Exchange (ETDEWEB)

    Bruyere, Emilie; Jonckheere, Nicolas; Frenois, Frederic [Inserm, UMR837, Jean-Pierre Aubert Research Center, Team 5 ' Mucins, Epithelial Differentiation and Carcinogenesis' , rue Polonovski, 59045 Lille Cedex (France); Universite Lille-Nord de France, 1 place de Verdun, 59045 Lille Cedex (France); Mariette, Christophe [Inserm, UMR837, Jean-Pierre Aubert Research Center, Team 5 ' Mucins, Epithelial Differentiation and Carcinogenesis' , rue Polonovski, 59045 Lille Cedex (France); Universite Lille-Nord de France, 1 place de Verdun, 59045 Lille Cedex (France); Department of Digestive and Oncological Surgery, University Hospital Claude Huriez, 1 place de Verdun, 59045 Lille Cedex (France); Van Seuningen, Isabelle, E-mail: isabelle.vanseuningen@inserm.fr [Inserm, UMR837, Jean-Pierre Aubert Research Center, Team 5 ' Mucins, Epithelial Differentiation and Carcinogenesis' , rue Polonovski, 59045 Lille Cedex (France); Universite Lille-Nord de France, 1 place de Verdun, 59045 Lille Cedex (France)

    2011-09-23

    Highlights: {yields} Loss of MUC4 reduces proliferation of esophageal cancer cells. {yields} MUC4 inhibition impairs migration of esophageal cancer cells but not their invasion. {yields} Loss of MUC4 significantly reduces in vivo tumor growth. {yields} Decrease of S100A4 induced by MUC4 inhibition impairs proliferation and migration. -- Abstract: MUC4 is a membrane-bound mucin known to participate in tumor progression. It has been shown that MUC4 pattern of expression is modified during esophageal carcinogenesis, with a progressive increase from metaplastic lesions to adenocarcinoma. The prin