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Kim SG, Sung JY, Kang YJ, Choi HC. Fisetin alleviates cellular senescence through PTEN mediated inhibition of PKCδ-NOX1 pathway in vascular smooth muscle cells. Arch Gerontol Geriatr 2023; 108:104927. [PMID: 36645971 DOI: 10.1016/j.archger.2023.104927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 11/29/2022] [Accepted: 01/08/2023] [Indexed: 01/13/2023]
Abstract
Reactive oxygen species (ROS) are a key risk factor of cellular senescence and age-related diseases, and protein kinase C (PKC) has been shown to activate NADPH oxidases (NOXs), which generate ROS. Although PKC activation induces oxidative stress, leading to the cellular dysfunction in various cell types, the correlation between PKC and senescence has not been reported in vascular smooth muscle cell (VSMC). Several studies have indicated cellular senescence is accompanied by phosphatase and tensin homolog (PTEN) loss and that an interaction exists between PTEN and PKC. Therefore, we aimed to determine whether PTEN and PKC are associated with VSMC senescence and to investigate the mechanism involved. We found hydrogen peroxide (H2O2) decreased PTEN expression and increased PKCδ phosphorylation. Moreover, H2O2 upregulated the NOX1 subunits, p22phox and p47phox, and induced VSMC senescence via p53-p21 signaling pathway. We identified PKCδ activation contributed to VSMC senescence through activation of NOX1 and ROS production. However, fisetin inhibited cellular senescence induced by the PTEN-PKCδ-NOX1-ROS signaling pathway, and this anti-aging effect was attributed to reduced ROS production caused by suppressing NOX1 activation. These results suggest that the PTEN-PCKδ signaling pathway is directly related to senescence via NOX1 activation and that the downregulation of PKCδ by flavonoids provides a potential means of treating age-associated diseases.
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Affiliation(s)
- Seul Gi Kim
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea; Senotherapy-based Metabolic Disease Control Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea
| | - Jin Young Sung
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea; Senotherapy-based Metabolic Disease Control Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea
| | - Young Jin Kang
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea
| | - Hyoung Chul Choi
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea; Senotherapy-based Metabolic Disease Control Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea.
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2
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Venuti A, Romero-Medina MC, Melita G, Ceraolo MG, Brancaccio RN, Sirand C, Taverniti V, Steenbergen R, Gheit T, Tommasino M. Lyon IARC Polyomavirus Displays Transforming Activities in Primary Human Cells. J Virol 2022; 96:e0206121. [PMID: 35770990 PMCID: PMC9327700 DOI: 10.1128/jvi.02061-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 06/13/2022] [Indexed: 01/01/2023] Open
Abstract
Several studies reported the presence of a recently discovered polyomavirus (PyV), Lyon IARC PyV (LIPyV), in human and domestic animal specimens. LIPyV has some structural similarities to well-established animal and human oncogenic PyVs, such as raccoon PyV and Merkel cell PyV (MCPyV), respectively. In this study, we demonstrate that LIPyV early proteins immortalize human foreskin keratinocytes. LIPyV LT binds pRb, accordingly cell cycle checkpoints are altered in primary human fibroblasts and keratinocytes expressing LIPyV early genes. Mutation of the pRb binding site in LT strongly affected the ability of LIPyV ER to induced HFK immortalization. LIPyV LT also binds p53 and alters p53 functions activated by cellular stresses. Finally, LIPyV early proteins activate telomerase reverse transcriptase (hTERT) gene expression, via accumulation of the Sp1 transcription factor. Sp1 recruitment to the hTERT promoter is controlled by its phosphorylation, which is mediated by ERK1 and CDK2. Together, these data highlight the transforming properties of LIPyV in in vitro experimental models, supporting its possible oncogenic nature. IMPORTANCE Lyon IARC PyV is a recently discovered polyomavirus that shows some structural similarities to well-established animal and human oncogenic PyVs, such as raccoon PyV and Merkel cell PyV, respectively. Here, we show the capability of LIPyV to efficiently promote cellular transformation of primary human cells, suggesting a possible oncogenic role of this virus in domestic animals and/or humans. Our study identified a novel virus-mediated mechanism of activation of telomerase reverse transcriptase gene expression, via accumulation of the Sp1 transcription factor. In addition, because the persistence of infection is a key event in virus-mediated carcinogenesis, it will be important to determine whether LIPyV can deregulate immune-related pathways, similarly to the well-established oncogenic viruses.
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Affiliation(s)
- Assunta Venuti
- International Agency for Research on Cancer (IARC), World Health Organization, Lyon Cedex, France
| | | | - Giusi Melita
- International Agency for Research on Cancer (IARC), World Health Organization, Lyon Cedex, France
| | - Maria Grazia Ceraolo
- International Agency for Research on Cancer (IARC), World Health Organization, Lyon Cedex, France
| | | | - Cecilia Sirand
- International Agency for Research on Cancer (IARC), World Health Organization, Lyon Cedex, France
| | - Valerio Taverniti
- International Agency for Research on Cancer (IARC), World Health Organization, Lyon Cedex, France
| | - Renske Steenbergen
- VU University Medical Center Amsterdam, Department of Pathology, Amsterdam, The Netherlands
| | - Tarik Gheit
- International Agency for Research on Cancer (IARC), World Health Organization, Lyon Cedex, France
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3
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Adnan M, Rasul A, Hussain G, Shah MA, Sarfraz I, Nageen B, Riaz A, Khalid R, Asrar M, Selamoglu Z, Adem Ş, Sarker SD. Physcion and Physcion 8-O-β-D-glucopyranoside: Natural Anthraquinones with Potential Anticancer Activities. Curr Drug Targets 2021; 22:488-504. [PMID: 33050858 DOI: 10.2174/1389450121999201013154542] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/18/2020] [Accepted: 06/09/2020] [Indexed: 11/22/2022]
Abstract
Nature has provided prodigious reservoirs of pharmacologically active compounds for drug development since times. Physcion and physcion 8-O-β-D-glucopyranoside (PG) are bioactive natural anthraquinones which exert anti-inflammatory and anticancer properties with minimum or no adverse effects. Moreover, physcion also exhibits anti-microbial and hepatoprotective properties, while PG is known to have anti-sepsis as well as ameliorative activities against dementia. This review aims to highlight the natural sources and anticancer activities of physcion and PG, along with associated mechanisms of actions. On the basis of the literature, physcion and PG regulate multitudinous cell signaling pathways through the modulation of various regulators of cell cycle, protein kinases, microRNAs, transcriptional factors, and apoptosis linked proteins resulting in the effective killing of cancerous cells in vitro as well as in vivo. Both compounds effectively suppress metastasis, furthermore, physcion acts as an inhibitor of 6PGD and also plays an important role in chemosensitization. This review article suggests that physcion and PG are potent anticancer drug candidates, but further investigations on their mechanism of action and pre-clinical trials are mandatory in order to comprehend the full potential of these natural cancer killers in anticancer remedies.
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Affiliation(s)
- Muhammad Adnan
- Department of Zoology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Azhar Rasul
- Department of Zoology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Ghulam Hussain
- Department of Physiology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Muhammad Ajmal Shah
- Department of Pharmacognosy, Faculty of Pharmaceutical Sciences, Government College University, Faisalabad, Pakistan
| | - Iqra Sarfraz
- Department of Zoology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Bushra Nageen
- Department of Zoology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Ammara Riaz
- Department of Zoology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Rida Khalid
- Department of Zoology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Muhammad Asrar
- Department of Zoology, Faculty of Life Sciences, Government College University, Faisalabad, Pakistan
| | - Zeliha Selamoglu
- Department of Medical Biology, Faculty of Medicine, Nigde Ömer Halisdemir University, Nigde, Campus 51240, Turkey
| | - Şevki Adem
- Department of Chemistry, Faculty of Sciences, Cankiri Karatekin University, UluyazI Campus Cankiri, Turkey
| | - Satyajit D Sarker
- School of Pharmacy & Biomolecular Sciences, Liverpool John Moores University, England, United Kingdom
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4
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Swift ML, Beishline K, Flashner S, Azizkhan-Clifford J. DSB repair pathway choice is regulated by recruitment of 53BP1 through cell cycle-dependent regulation of Sp1. Cell Rep 2021; 34:108840. [PMID: 33730584 DOI: 10.1016/j.celrep.2021.108840] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 09/13/2020] [Accepted: 02/17/2021] [Indexed: 12/14/2022] Open
Abstract
Although many of the factors, epigenetic changes, and cell cycle stages that distinguish repair of double-strand breaks (DSBs) by homologous recombination (HR) from non-homologous end joining (NHEJ) are known, the underlying mechanisms that determine pathway choice are incompletely understood. Previously, we found that the transcription factor Sp1 is recruited to DSBs and is necessary for repair. Here, we demonstrate that Sp1 localizes to DSBs in G1 and is necessary for recruitment of the NHEJ repair factor, 53BP1. Phosphorylation of Sp1-S59 in early S phase evicts Sp1 and 53BP1 from the break site; inhibition of that phosphorylation results in 53BP1 and Sp1 remaining at DSBs in S phase cells, precluding BRCA1 binding and suppressing HR. Expression of Sp1-S59A increases sensitivity of BRCA1+/+ cells to poly (ADP-ribose) polymerase (PARP) inhibition similar to BRCA1 deficiency. These data demonstrate how Sp1 integrates the cell cycle and DSB repair pathway choice to favor NHEJ.
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Affiliation(s)
- Michelle L Swift
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Kate Beishline
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Samuel Flashner
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Jane Azizkhan-Clifford
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, USA.
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5
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Lee YY, Choi YS, Kim DW, Cheong JY, Song KY, Ryu MS, Lim IK. Mitochondrial nucleoid remodeling and biogenesis are regulated by the p53-p21 WAF1-PKCζ pathway in p16 INK4a-silenced cells. Aging (Albany NY) 2020; 12:6700-6732. [PMID: 32330121 PMCID: PMC7202532 DOI: 10.18632/aging.103029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 02/22/2020] [Indexed: 11/25/2022]
Abstract
Mitochondrial dysfunction is linked to age-related senescence phenotypes. We report here the pathway increasing nucleoid remodeling and biogenesis in mitochondria during the senescence of foreskin human diploid fibroblasts (fs-HDF) and WI-38 cells. Replicative senescence in fs-HDF cells increased mitochondrial nucleoid remodeling as indicated by 5-bromo-2'-deoxyuridine (BrdU) incorporation and mitochondrial transcription factor A (TFAM) expression in enlarged and fused mitochondria. Mitochondrial nucleoid remodeling was accompanied by mitochondrial biogenesis in old cells, and the expression levels of OXPHOS complex-I, -IV and -V subunits, PGC-1α and NRF1 were greatly increased compared to young cells. Activated protein kinase C zeta (PKCζ) increased mitochondrial activity and expressed phenotypes of delayed senescence in fs-HDF cells, but not in WI-38 cells. The findings were reproduced in the doxorubicin-induced senescence of young fs-HDF and WI-38 cells via the PKCζ-LKB1-AMPK signaling pathway, which was regulated by the p53-p21WAF1 pathway when p16INK4a was silenced. The signaling enhanced PGC-1α-NRF1-TFAM axis in mitochondria, which was demonstrated by Ingenuity Pathway Analysis of young and old fs-HDF cells. Activation of the p53-p21WAF1 pathway and silencing of p16INK4a are responsible for mitochondrial reprogramming in senescent cells, which may be a compensatory mechanism to promote cell survival under senescence stress.
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Affiliation(s)
- Yun Yeong Lee
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Otolaryngology, Ajou University School of Medicine, Suwon 16499, Korea
| | - Yeon Seung Choi
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, The Graduate School, Ajou University, Suwon 16499, Korea
| | - Do Wan Kim
- Omics Center, Ajou University School of Medicine, Suwon 16499, Korea
| | - Jae Youn Cheong
- Omics Center, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Gastroenterology, Ajou University of Medicine, Suwon 16499, Korea
| | - Kye Yong Song
- Department of Pathology, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Min Sook Ryu
- Department of Biomedical Sciences, The Graduate School, Ajou University, Suwon 16499, Korea
| | - In Kyoung Lim
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, The Graduate School, Ajou University, Suwon 16499, Korea
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6
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Peng F, Zhou Y, Wang J, Guo B, Wei Y, Deng H, Wu Z, Zhang C, Shi K, Li Y, Wang X, Shore P, Zhao S, Deng W. The transcription factor Sp1 modulates RNA polymerase III gene transcription by controlling BRF1 and GTF3C2 expression in human cells. J Biol Chem 2020; 295:4617-4630. [PMID: 32115405 DOI: 10.1074/jbc.ra119.011555] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/16/2020] [Indexed: 01/10/2023] Open
Abstract
Specificity protein 1 (Sp1) is an important transcription factor implicated in numerous cellular processes. However, whether Sp1 is involved in the regulation of RNA polymerase III (Pol III)-directed gene transcription in human cells remains unknown. Here, we first show that filamin A (FLNA) represses Sp1 expression as well as expression of TFIIB-related factor 1 (BRF1) and general transcription factor III C subunit 2 (GTF3C2) in HeLa, 293T, and SaOS2 cell lines stably expressing FLNA-silencing shRNAs. Both BRF1 promoter 4 (BRF1P4) and GTF3C2 promoter 2 (GTF3C2P2) contain putative Sp1-binding sites, suggesting that Sp1 affects Pol III gene transcription by regulating BRF1 and GTF3C2 expression. We demonstrate that Sp1 knockdown inhibits Pol III gene transcription, BRF1 and GTF3C2 expression, and the proliferation of 293T and HeLa cells, whereas Sp1 overexpression enhances these activities. We obtained a comparable result in a cell line in which both FLNA and Sp1 were depleted. These results indicate that Sp1 is involved in the regulation of Pol III gene transcription independently of FLNA expression. Reporter gene assays showed that alteration of Sp1 expression affects BRF1P4 and GTF3C2P2 activation, suggesting that Sp1 modulates Pol III-mediated gene transcription by controlling BRF1 and GTF3C2 gene expression. Further analysis revealed that Sp1 interacts with and thereby promotes the occupancies of TATA box-binding protein, TFIIAα, and p300 at both BRF1P4 and GTF3C2P2. These findings indicate that Sp1 controls Pol III-directed transcription and shed light on how Sp1 regulates cancer cell proliferation.
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Affiliation(s)
- Feixia Peng
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Ying Zhou
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Juan Wang
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Baoqiang Guo
- Centre for Bioscience, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester M1 5GD, United Kingdom
| | - Yun Wei
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Huan Deng
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Zihui Wu
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Cheng Zhang
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Kaituo Shi
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Yuan Li
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Xin Wang
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Paul Shore
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Shasha Zhao
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Wensheng Deng
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
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7
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TRIM59 expression is regulated by Sp1 and Nrf1 in LPS-activated macrophages through JNK signaling pathway. Cell Signal 2019; 67:109522. [PMID: 31883458 DOI: 10.1016/j.cellsig.2019.109522] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/23/2019] [Accepted: 12/23/2019] [Indexed: 12/19/2022]
Abstract
Activated macrophages play an important role in many inflammatory diseases including septic shock and atherosclerosis. TRIM59 has been showed to participate in many pathological processes, such as inflammation, cytotoxicity and tumorigenesis. However, the molecular mechanisms controlling its expression in activated macrophages are not fully understood. Here we report that TRIM59 expression is regulated by Sp1 and Nrf1 in LPS-activated macrophages. TRIM59 is highly expressed in macrophages, and markedly decreased by LPS stimuli in vivo and in vitro. TRIM59 promoter activity is also significantly suppressed by LPS and further analysis demonstrated that Sp1 and Nrf1 directly bound to the proximal promoter of TRIM59 gene. LPS treatment significantly decreased Sp1 expression, nuclear translocation and reduced its binding to the promoter, whereas increased Nrf1 expression, nuclear translocation and enhanced its binding to the promoter. Moreover, LPS-decreased TRIM59 expression was reversed by JNK inhibitor. Finally, TRIM59 level is significantly decreased during atherosclerosis progression. Taken together, our results demonstrated that TRIM59 expression was precisely regulated by Sp1 and Nrf1 in LPS-activated macrophages, which may be dependent on the activation of JNK signaling pathway and TRIM59 may be a potential therapeutic target for inflammatory diseases such as atherosclerosis.
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8
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An Effective Model of the Retinoic Acid Induced HL-60 Differentiation Program. Sci Rep 2017; 7:14327. [PMID: 29085021 PMCID: PMC5662654 DOI: 10.1038/s41598-017-14523-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 10/11/2017] [Indexed: 12/17/2022] Open
Abstract
In this study, we present an effective model All-Trans Retinoic Acid (ATRA)-induced differentiation of HL-60 cells. The model describes reinforcing feedback between an ATRA-inducible signalsome complex involving many proteins including Vav1, a guanine nucleotide exchange factor, and the activation of the mitogen activated protein kinase (MAPK) cascade. We decomposed the effective model into three modules; a signal initiation module that sensed and transformed an ATRA signal into program activation signals; a signal integration module that controlled the expression of upstream transcription factors; and a phenotype module which encoded the expression of functional differentiation markers from the ATRA-inducible transcription factors. We identified an ensemble of effective model parameters using measurements taken from ATRA-induced HL-60 cells. Using these parameters, model analysis predicted that MAPK activation was bistable as a function of ATRA exposure. Conformational experiments supported ATRA-induced bistability. Additionally, the model captured intermediate and phenotypic gene expression data. Knockout analysis suggested Gfi-1 and PPARg were critical to the ATRAinduced differentiation program. These findings, combined with other literature evidence, suggested that reinforcing feedback is central to hyperactive signaling in a diversity of cell fate programs.
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9
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Survive or thrive: tradeoff strategy for cellular senescence. Exp Mol Med 2017; 49:e342. [PMID: 28572574 PMCID: PMC5519021 DOI: 10.1038/emm.2017.94] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/06/2017] [Accepted: 02/16/2017] [Indexed: 12/12/2022] Open
Abstract
Aging-dependent cellular behaviors toward extrinsic stress are characterized by the confined localization of certain molecules to either nuclear or perinuclear regions. Although most growth factors can activate downstream signaling in aging cells, they do not in fact have any impact on the cells because the signals cannot reach their genetic targets in the nucleus. For the same reason, varying apoptotic stress factors cannot stimulate the apoptotic pathway in senescent cells. Thus, the operation of a functional nuclear barrier in an aging-dependent manner has been investigated. To elucidate the mechanism for this process, the housekeeping transcription factor Sp1 was identified as a general regulator of nucleocytoplasmic trafficking (NCT) genes, including various nucleoporins, importins, exportins and Ran GTPase cycle-related genes. Interestingly, the posttranslational modification of Sp1 is readily influenced by extrinsic stress, including oxidative and metabolic stress. The decrease in SP1 O-GlcNAcylation under oxidative stress or during replicative senescence makes it susceptible to proteosomal degradation, resulting in defective NCT functions and leading to nuclear barrier formation. The operation of the nuclear barrier in aging provides a fundamental mechanism for cellular protection against stress and promotes survival at the expense of growth via stress-sensitive transcriptional control.
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10
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Wang Q, Wang Y, Xing Y, Yan Y, Guo P, Zhuang J, Qin F, Zhang J. RETRACTED: Physcion 8-O-β-glucopyranoside induces apoptosis, suppresses invasion and inhibits epithelial to mesenchymal transition of hepatocellular carcinoma HepG2 cells. Biomed Pharmacother 2016; 83:372-380. [PMID: 27416558 DOI: 10.1016/j.biopha.2016.06.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 06/22/2016] [Accepted: 06/25/2016] [Indexed: 12/12/2022] Open
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Panels from Figure 4A appear similar to panels from Figure 1 of the article previously published by Z. Ding, F. Xu, J. Tang, G. Li, P. Jiang, Z. Tang and H. Wu in Neoplasma 63(3) (2016) 351–361 http://www.elis.sk/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=4703&category_id=128&option=com_virtuemart&vmcchk=1&Itemid=1. One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper has not been previously published and is not under consideration for publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a misuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
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Affiliation(s)
- Qiang Wang
- Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Yong Wang
- Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Yuqing Xing
- Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Yi Yan
- Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Peng Guo
- Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Jianguang Zhuang
- Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Fawei Qin
- Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Jie Zhang
- Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China.
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11
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Kim JE, Shin JS, Moon JH, Hong SW, Jung DJ, Kim JH, Hwang IY, Shin YJ, Gong EY, Lee DH, Kim SM, Lee EY, Kim YS, Kim D, Hur D, Kim TW, Kim KP, Jin DH, Lee WJ. Foxp3 is a key downstream regulator of p53-mediated cellular senescence. Oncogene 2016; 36:219-230. [DOI: 10.1038/onc.2016.193] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 04/18/2016] [Accepted: 04/26/2016] [Indexed: 11/09/2022]
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12
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Sacco F, Silvestri A, Posca D, Pirrò S, Gherardini PF, Castagnoli L, Mann M, Cesareni G. Deep Proteomics of Breast Cancer Cells Reveals that Metformin Rewires Signaling Networks Away from a Pro-growth State. Cell Syst 2016; 2:159-71. [PMID: 27135362 DOI: 10.1016/j.cels.2016.02.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 12/02/2015] [Accepted: 02/01/2016] [Indexed: 12/25/2022]
Abstract
Metformin is the most frequently prescribed drug for type 2 diabetes. In addition to its hypoglycemic effects, metformin also lowers cancer incidence. This anti-cancer activity is incompletely understood. Here, we profiled the metformin-dependent changes in the proteome and phosphoproteome of breast cancer cells using high-resolution mass spectrometry. In total, we quantified changes of 7,875 proteins and 15,813 phosphosites after metformin changes. To interpret these datasets, we developed a generally applicable strategy that overlays metformin-dependent changes in the proteome and phosphoproteome onto a literature-derived network. This approach suggested that metformin treatment makes cancer cells more sensitive to apoptotic stimuli and less sensitive to pro-growth stimuli. These hypotheses were tested in vivo; as a proof-of-principle, we demonstrated that metformin inhibits the p70S6K-rpS6 axis in a PP2A-phosphatase dependent manner. In conclusion, analysis of deep proteomics reveals both detailed and global mechanisms that contribute to the anti-cancer activity of metformin.
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Affiliation(s)
- Francesca Sacco
- Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy; Department Proteomics and Signal Transduction, Max-Planck Institute of Biochemistry, Martinsried, Germany
| | | | - Daniela Posca
- Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Stefano Pirrò
- Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy
| | | | - Luisa Castagnoli
- Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Matthias Mann
- Department Proteomics and Signal Transduction, Max-Planck Institute of Biochemistry, Martinsried, Germany.
| | - Gianni Cesareni
- Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy; Istituto Ricovero e Cura a Carattere Scientifico, Fondazione Santa Lucia, Rome, Italy.
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13
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Lee YY, Ryu MS, Kim HS, Suganuma M, Song KY, Lim IK. Regulations of Reversal of Senescence by PKC Isozymes in Response to 12-O-Tetradecanoylphorbol-13-Acetate via Nuclear Translocation of pErk1/2. Mol Cells 2016; 39:266-79. [PMID: 26912086 PMCID: PMC4794609 DOI: 10.14348/molcells.2016.2362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 12/31/2015] [Indexed: 11/27/2022] Open
Abstract
The mechanism by which 12-O-tetradecanoylphorbol-13-acetate (TPA) bypasses cellular senescence was investigated using human diploid fibroblast (HDF) cell replicative senescence as a model. Upon TPA treatment, protein kinase C (PKC) α and PKCβ1 exerted differential effects on the nuclear translocation of cytoplasmic pErk1/2, a protein which maintains senescence. PKCα accompanied pErk1/2 to the nucleus after freeing it from PEA-15pS(104) via PKCβ1 and then was rapidly ubiquitinated and degraded within the nucleus. Mitogen-activated protein kinase docking motif and kinase activity of PKCα were both required for pErk1/2 transport to the nucleus. Repetitive exposure of mouse skin to TPA downregulated PKCα expression and increased epidermal and hair follicle cell proliferation. Thus, PKCα downregulation is accompanied by in vivo cell proliferation, as evidenced in 7, 12-dimethylbenz(a)anthracene (DMBA)-TPA-mediated carcinogenesis. The ability of TPA to reverse senescence was further demonstrated in old HDF cells using RNA-sequencing analyses in which TPA-induced nuclear PKCα degradation freed nuclear pErk1/2 to induce cell proliferation and facilitated the recovery of mitochondrial energy metabolism. Our data indicate that TPA-induced senescence reversal and carcinogenesis promotion share the same molecular pathway. Loss of PKCα expression following TPA treatment reduces pErk1/2-activated SP1 biding to the p21(WAF1) gene promoter, thus preventing senescence onset and overcoming G1/S cell cycle arrest in senescent cells.
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Affiliation(s)
- Yun Yeong Lee
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon 443-380,
Korea
| | - Min Sook Ryu
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon 443-380,
Korea
| | | | - Masami Suganuma
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama,
Japan
| | - Kye Yong Song
- Department of Pathology, Chung-Ang University College of Medicine, Seoul 156-756,
Korea
| | - In Kyoung Lim
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon 443-380,
Korea
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14
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Mass spectrometric phosphoproteome analysis of small-sized samples of human neutrophils. Clin Chim Acta 2015; 451:199-207. [DOI: 10.1016/j.cca.2015.09.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 09/21/2015] [Accepted: 09/29/2015] [Indexed: 12/28/2022]
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15
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Lee YY, Kim HS, Lim IK. Downregulation of PEA-15 reverses G1 arrest, and nuclear and chromatin changes of senescence phenotype via pErk1/2 translocation to nuclei. Cell Signal 2015; 27:1102-9. [PMID: 25725291 DOI: 10.1016/j.cellsig.2015.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 02/17/2015] [Indexed: 11/30/2022]
Abstract
We previously showed that senescent cells respond to TPA with translocation of senescence associated-pErk1/2 (SA-pErk1/2) into nuclei along with reversal of senescence morphology. Here, we describe that the reversal of senescence phenotype was manifested by knockdown of cytoplasmic PEA-15 expression, a sequestrator of cytoplasmic pErk1/2. Transfection of short-interfering RNA to PEA-15 (siPEA-15) significantly induced nuclear translocation of SA-pErk1/2, and siPEA-15 with TPA co-treatment further increased the translocation. Moreover, the reversal of senescence phenotype, such as expressions of SA-β-galactosidase, p53, p21(WAF1), PML body, 53BP1 and H3K9me2, was modified by either knockdown of PEA-15 or TPA treatment, indicating that nuclear translocation of SA-pErk1/2 might inhibit senescence progression. Indeed, knockdown of PEA-15 or TPA treatment significantly induced progression of G1 arrested cells to S-phase in human diploid fibroblast (HDF) senescent cells, examined by immunocytochemistry, FACS and immunoblot analyses. In conclusion, downregulation of PEA-15 expression reverses senescence phenotypes via nuclear translocation of SA-pErk1/2, which suggests in vivo maintenance of senescence phenotype by sequestration of pErk1/2 in cytoplasm.
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Affiliation(s)
- Yun Yeong Lee
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, World cup-ro 164, Suwon 443-380, Republic of Korea; Department of Biomedical Sciences, The Graduate School, Ajou University, World cup-ro 164, Suwon 443-380, Republic of Korea
| | - Hong Seok Kim
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, World cup-ro 164, Suwon 443-380, Republic of Korea
| | - In Kyoung Lim
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, World cup-ro 164, Suwon 443-380, Republic of Korea; Department of Biomedical Sciences, The Graduate School, Ajou University, World cup-ro 164, Suwon 443-380, Republic of Korea.
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16
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Beishline K, Azizkhan-Clifford J. Sp1 and the 'hallmarks of cancer'. FEBS J 2015; 282:224-58. [PMID: 25393971 DOI: 10.1111/febs.13148] [Citation(s) in RCA: 369] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 09/26/2014] [Accepted: 11/10/2014] [Indexed: 12/19/2022]
Abstract
For many years, transcription factor Sp1 was viewed as a basal transcription factor and relegated to a role in the regulation of so-called housekeeping genes. Identification of Sp1's role in recruiting the general transcription machinery in the absence of a TATA box increased its importance in gene regulation, particularly in light of recent estimates that the majority of mammalian genes lack a TATA box. In this review, we briefly consider the history of Sp1, the founding member of the Sp family of transcription factors. We review the evidence suggesting that Sp1 is highly regulated by post-translational modifications that positively and negatively affect the activity of Sp1 on a wide array of genes. Sp1 is over-expressed in many cancers and is associated with poor prognosis. Targeting Sp1 in cancer treatment has been suggested; however, our review of the literature on the role of Sp1 in the regulation of genes that contribute to the 'hallmarks of cancer' illustrates the extreme complexity of Sp1 functions. Sp1 both activates and suppresses the expression of a number of essential oncogenes and tumor suppressors, as well as genes involved in essential cellular functions, including proliferation, differentiation, the DNA damage response, apoptosis, senescence and angiogenesis. Sp1 is also implicated in inflammation and genomic instability, as well as epigenetic silencing. Given the apparently opposing effects of Sp1, a more complete understanding of the function of Sp1 in cancer is required to validate its potential as a therapeutic target.
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Affiliation(s)
- Kate Beishline
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, USA
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17
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Ho PJ, Yen ML, Tang BC, Chen CT, Yen BL. H2O2 accumulation mediates differentiation capacity alteration, but not proliferative decline, in senescent human fetal mesenchymal stem cells. Antioxid Redox Signal 2013; 18:1895-905. [PMID: 23088254 PMCID: PMC3624695 DOI: 10.1089/ars.2012.4692] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
AIMS Mesenchymal stem cells (MSCs) with multilineage differentiation capacity and immunomodulatory properties are novel sources for cell therapy. However, in vitro expansion of these rare somatic stem cells leads to senescence, resulting in declines of differentiation and proliferative capacities. We therefore investigated the mechanisms mediating senescence in human fetal MSCs termed placenta-derived multipotent cells (PDMCs). RESULTS Long-term cultured PDMCs underwent senescence, with increased levels of hydrogen peroxide (H2O2; a reactive oxygen species), positive β-galactosidase staining, decreased sirtuin-1 expression, increased p21 expression, and cell cycle arrest at the G0/G1 phase. Senescent PDMCs also showed decreased osteogenic capacity. Mechanistically, increased p21 expression and proliferative decline were not due to elevated H2O2 levels nor mediated by p53. Instead, inhibition of protein kinase C (PKC)-α and -β in senescent PDMCs decreased p21 expression and reversed cell cycle arrest. H2O2 was involved in the alteration of differentiation potential, since scavenging of H2O2 restored expression of c-MAF, an osteogenic and age-sensitive transcription factor, and osteogenic capacity in senescent PDMCs. INNOVATION Our findings not only show the effects of senescence on MSCs, but also reveal mechanisms involved in mediating decreased proliferation and differentiation capacity. Moreover, targeting increased levels of H2O2 associated with senescence may reverse the decreased osteogenic capacity of senescent MSCs. CONCLUSION Our study suggests that the two biological consequences of senescence, differentiation alteration, and proliferative decline, in fetal MSCs are distinctly regulated by the H2O2-c-MAF and PKC-p21 pathways, respectively.
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Affiliation(s)
- Pai-Jiun Ho
- Regenerative Medicine Research Group, Institute of Cellular and System Medicine ICSM, National Health Research Institute NHRI, Zhunan 350, Taiwan
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18
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Biswas S, Mukherjee R, Tapryal N, Singh AK, Mukhopadhyay CK. Insulin regulates hypoxia-inducible factor-1α transcription by reactive oxygen species sensitive activation of Sp1 in 3T3-L1 preadipocyte. PLoS One 2013; 8:e62128. [PMID: 23626778 PMCID: PMC3633924 DOI: 10.1371/journal.pone.0062128] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 03/19/2013] [Indexed: 01/04/2023] Open
Abstract
Oxygen sensing transcription factor HIF-1 is activated due to accumulation of regulatory subunit HIF-1α by posttranslational stability mechanism during hypoxia or by several other stimuli even in normoxia. HIF-1α is also regulated by NF-kB mediated transcription mechanism. Reactive oxygen species (ROS) act as an important regulator of HIF-1 either by affecting prolyl hydroxylase activity, the critical determinant of HIF-1α stabilization or by activating NF-kB to promote HIF-1α transcription. Insulin is known to activate HIF-1 by a ROS dependent mechanism but the molecular mechanism of HIF-1α regulation is not known so far. Here we show that insulin regulates HIF-1α by a novel transcriptional mechanism by a ROS-sensitive activation of Sp1 in 3T3-L1 preadipocyte. Insulin shows little effect on HIF-1α protein stability, but increases HIF-1α promoter activity. Mutation analyses, electrophoretic mobility shift assay and chromatin immunoprecipitation assay confirm the role of Sp1 in HIF-1α transcription. We further demonstrate that insulin-induced ROS generation initiates signaling pathway involving phosphatidylinositol 3-kinase and protein kinase C for Sp1 mediated HIF-1α transcription. In summary, we reveal that insulin regulates HIF-1α by a novel transcriptional mechanism involving Sp1.
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Affiliation(s)
- Sudipta Biswas
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Reshmi Mukherjee
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Nisha Tapryal
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Amit K. Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Chinmay K. Mukhopadhyay
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
- * E-mail:
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19
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Amato R, Scumaci D, D'Antona L, Iuliano R, Menniti M, Di Sanzo M, Faniello MC, Colao E, Malatesta P, Zingone A, Agosti V, Costanzo FS, Mileo AM, Paggi MG, Lang F, Cuda G, Lavia P, Perrotti N. Sgk1 enhances RANBP1 transcript levels and decreases taxol sensitivity in RKO colon carcinoma cells. Oncogene 2012; 32:4572-8. [PMID: 23108393 DOI: 10.1038/onc.2012.470] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 08/01/2012] [Accepted: 08/21/2012] [Indexed: 12/16/2022]
Abstract
The serum- and glucocorticoid-regulated kinase (Sgk1) is essential for hormonal regulation of epithelial sodium channel-mediated sodium transport and is involved in the transduction of growth factor-dependent cell survival and proliferation signals. Growing evidence now points to Sgk1 as a key element in the development and/or progression of human cancer. To gain insight into the mechanisms through which Sgk1 regulates cell proliferation, we adopted a proteomic approach to identify up- or downregulated proteins after Sgk1-specific RNA silencing. Among several proteins, the abundance of which was found to be up- or downregulated upon Sgk1 silencing, we focused our attention of RAN-binding protein 1 (RANBP1), a major effector of the GTPase RAN. We report that Sgk1-dependent regulation of RANBP1 has functional consequences on both mitotic microtubule activity and taxol sensitivity of cancer cells.
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Affiliation(s)
- R Amato
- Department of Human Health, University Magna Graecia at Catanzaro, Campus S Venuta, Località Germaneto Viale Europa, Catanzaro, Italy
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20
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Transcriptional regulation by post-transcriptional modification—Role of phosphorylation in Sp1 transcriptional activity. Gene 2012; 508:1-8. [DOI: 10.1016/j.gene.2012.07.022] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 05/22/2012] [Accepted: 07/16/2012] [Indexed: 01/05/2023]
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21
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Bigot N, Beauchef G, Hervieu M, Oddos T, Demoor M, Boumediene K, Galéra P. NF-κB Accumulation Associated with COL1A1 Trans activators Defects during Chronological Aging Represses Type I Collagen Expression through a –112/–61-bp Region of the COL1A1 Promoter in Human Skin Fibroblasts. J Invest Dermatol 2012; 132:2360-2367. [DOI: 10.1038/jid.2012.164] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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22
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Promoter cloning and characterization of the human programmed cell death protein 4 (pdcd4) gene: evidence for ZBP-89 and Sp-binding motifs as essential Pdcd4 regulators. Biosci Rep 2012; 32:281-97. [DOI: 10.1042/bsr20110045] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Pdcd4 (programmed cell death protein 4) is an important novel tumour suppressor inhibiting transformation, translation, invasion and intravasation, and its expression is down-regulated in several cancers. However, little is known about the transcriptional regulation and the promoter of this important tumour suppressor. So far the following is the first comprehensive study to describe the regulation of Pdcd4 transcription by ZBP-89 (zinc-finger-binding protein 89), besides characterizing the gene promoter. We identified the transcriptional start sites of the human pdcd4 promoter, a functional CCAAT-box, and the basal promoter region. Within this basal region, computer-based analysis revealed several potential binding sites for ZBPs, especially for Sp (specificity protein) family members and ZBP-89. We identified four Sp1/Sp3/Sp4-binding elements to be indispensable for basal promoter activity. However, overexpression of Sp1 and Sp3 was not sufficient to enhance Pdcd4 protein expression. Analysis in different solid cancer cell lines showed a significant correlation between pdcd4 and zbp-89 mRNA amounts. In contrast with Sp transcription factors, overexpression of ZBP-89 led to an enhanced expression of Pdcd4 mRNA and protein. Additionally, specific knockdown of ZBP-89 resulted in a decreased pdcd4 gene expression. Reporter gene analysis showed a significant up-regulation of basal promoter activity by co-transfection with ZBP-89, which could be abolished by mithramycin treatment. Predicted binding of ZBP-89 to the basal promoter was confirmed by EMSA (electrophoretic mobility-shift assay) data and supershift analysis for ZBP-89. Taken together, data for the first time implicate ZBP-89 as a regulator of Pdcd4 by binding to the basal promoter either alone or by interacting with Sp family members.
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23
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Choi OR, Lim IK. Loss of p21(Sdi1) expression in senescent cells after DNA damage accompanied with increase of miR-93 expression and reduced p53 interaction with p21(Sdi1) gene promoter. Biochem Biophys Res Commun 2011; 407:406-11. [PMID: 21402054 DOI: 10.1016/j.bbrc.2011.03.038] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Accepted: 03/09/2011] [Indexed: 12/20/2022]
Abstract
To answer what is a critical event for higher incidence of tumor development in old than young individuals, primary culture of human diploid fibroblasts were employed and DNA damage was induced by doxorubicin or X-ray irradiation. Response to the damage was different between young and old cells; loss of p21(sdi1) expression in spite of p53(S¹⁵) activation in old cells along with [³H]thymidine and BrdU incorporation, but not in young cells. The phenomenon was confirmed by other tissue fibroblasts obtained from different donor ages. Induction of miR-93 expression and reduced p53 binding to p21 gene promoter account for loss of p21(sdi1) expression in senescent cells after DNA damage, suggesting a mechanism of in vivo carcinogenesis in aged tissue without repair arrest.
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Affiliation(s)
- Ok Ran Choi
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon 443-721, Republic of Korea
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24
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Park SH, Park TJ, Lim IK. Reduction of exportin 6 activity leads to actin accumulation via failure of RanGTP restoration and NTF2 sequestration in the nuclei of senescent cells. Exp Cell Res 2010; 317:941-54. [PMID: 21195711 DOI: 10.1016/j.yexcr.2010.12.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 12/20/2010] [Accepted: 12/25/2010] [Indexed: 10/18/2022]
Abstract
We have previously reported that G-actin accumulation in nuclei is a universal phenomenon of cellular senescence. By employing primary culture of human diploid fibroblast (HDF) and stress-induced premature senescence (SIPS), we explored whether the failure of actin export to cytoplasm is responsible for actin accumulation in nuclei of senescent cells. Expression of exportin 6 (Exp6) and small G-protein, Ran, was significantly reduced in the replicative senescence, but not yet in SIPS, whereas nuclear import of actin by cofilin was already increased in SIPS. After treatment of young HDF cells with H(2)O(2), rapid reduction of nuclear RanGTP was observed along with cytoplasmic increase of RanGDP. Furthermore, significantly reduced interaction of Exp6 with RanGTP was found by GST-Exp6 pull-down analysis. Failure of RanGTP restoration was accompanied with inhibition of ATP synthesis and NTF2 sequestration in the nuclei along with accordant change of senescence morphology. Indeed, knockdown of Exp6 expression significantly increased actin molecule in the nuclei of young HDF cells. Therefore, actin accumulation in nuclei of senescent cells is most likely due to the failure of RanGTP restoration with ATP deficiency and NTF2 accumulation in nuclei, which result in the decrease of actin export via Exp6 inactivation, in addition to actin import by cofilin activation.
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Affiliation(s)
- Su Hyun Park
- Department of Biochemistry and Molecular Biology, BK21 Division of Cell Transformation and Restoration, Ajou University School of Medicine, Suwon 443-721, Republic of Korea
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25
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Alemu EA, Sjøttem E, Outzen H, Larsen KB, Holm T, Bjørkøy G, Johansen T. Transforming growth factor-β-inducible early response gene 1 is a novel substrate for atypical protein kinase Cs. Cell Mol Life Sci 2010; 68:1953-68. [PMID: 20953893 PMCID: PMC3092057 DOI: 10.1007/s00018-010-0541-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 09/03/2010] [Accepted: 09/27/2010] [Indexed: 11/25/2022]
Abstract
The protein kinase C (PKC) family of serine/threonine kinases consists of ten different isoforms grouped into three subfamilies, denoted classical, novel and atypical PKCs (aPKCs). The aPKCs, PKCι/λ and PKCζ serve important roles during development and in processes subverted in cancer such as cell and tissue polarity, cell proliferation, differentiation and apoptosis. In an effort to identify novel interaction partners for aPKCs, we performed a yeast two-hybrid screen with the regulatory domain of PKCι/λ as bait and identified the Krüppel-like factors family protein TIEG1 as a putative interaction partner for PKCι/λ. We confirmed the interaction of both aPKCs with TIEG1 in vitro and in cells, and found that both aPKCs phosphorylate the DNA-binding domain of TIEG1 on two critical residues. Interestingly, the aPKC-mediated phosphorylation of TIEG1 affected its DNA-binding activity, subnuclear localization and transactivation potential.
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Affiliation(s)
- Endalkachew A. Alemu
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsö, 9037 Tromsö, Norway
| | - Eva Sjøttem
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsö, 9037 Tromsö, Norway
| | - Heidi Outzen
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsö, 9037 Tromsö, Norway
| | - Kenneth B. Larsen
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsö, 9037 Tromsö, Norway
| | - Turid Holm
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsö, 9037 Tromsö, Norway
| | - Geir Bjørkøy
- University College of Sør-Trøndelag, 7006 Trondheim, Norway
| | - Terje Johansen
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsö, 9037 Tromsö, Norway
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26
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Saito Y, Murata-Kamiya N, Hirayama T, Ohba Y, Hatakeyama M. Conversion of Helicobacter pylori CagA from senescence inducer to oncogenic driver through polarity-dependent regulation of p21. ACTA ACUST UNITED AC 2010; 207:2157-74. [PMID: 20855497 PMCID: PMC2947069 DOI: 10.1084/jem.20100602] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The Helicobacter pylori CagA bacterial oncoprotein plays a critical role in gastric carcinogenesis. Upon delivery into epithelial cells, CagA causes loss of polarity and activates aberrant Erk signaling. We show that CagA-induced Erk activation results in senescence and mitogenesis in nonpolarized and polarized epithelial cells, respectively. In nonpolarized epithelial cells, Erk activation results in oncogenic stress, up-regulation of the p21(Waf1/Cip1) cyclin-dependent kinase inhibitor, and induction of senescence. In polarized epithelial cells, CagA-driven Erk signals prevent p21(Waf1/Cip1) expression by activating a guanine nucleotide exchange factor-H1-RhoA-RhoA-associated kinase-c-Myc pathway. The microRNAs miR-17 and miR-20a, induced by c-Myc, are needed to suppress p21(Waf1/Cip1) expression. CagA also drives an epithelial-mesenchymal transition in polarized epithelial cells. These findings suggest that CagA exploits a polarity-signaling pathway to induce oncogenesis.
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Affiliation(s)
- Yasuhiro Saito
- Division of Microbiology, Graduate School of Medicine, University of Tokyo, Tokyo 113-0033, Japan
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27
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Li G, Luna C, Qiu J, Epstein DL, Gonzalez P. Alterations in microRNA expression in stress-induced cellular senescence. Mech Ageing Dev 2009; 130:731-41. [PMID: 19782699 PMCID: PMC2795064 DOI: 10.1016/j.mad.2009.09.002] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2009] [Revised: 08/14/2009] [Accepted: 09/16/2009] [Indexed: 02/08/2023]
Abstract
We investigated miRNA expression changes associated with stress-induced premature senescence (SIPS) in primary cultures of human diploid fibroblast (HDF) and human trabecular meshwork (HTM) cells. Twenty-five miRNAs were identified by miRNA microarray analysis and their changes in expression were validated by TaqMan real-time RT-PCR in three independent cell lines of HTM and HDF. SIPS in both HTM and HDF cell types was associated with significant down-regulation of four members of the miR-15 family and five miRNAs of the miR-106b family located in the oncogenic clusters miR-17-92, miR-106a-363, and miR-106b-25. SIPS was also associated with up-regulation of two miRNAs (182 and 183) from the miR-183-96-182 cluster. Transfection with miR-106a agomir inhibited the up-regulation of p21(CDKN1A) associated with SIPS while transfection with miR-106a antagomir led to increased p21(CDKN1A) expression in senescent cells. In addition, we identified retinoic acid receptor gamma (RARG) as a target of miR-182 and showed that this protein was down-regulated during SIPS in HDF and HTM cells. These results suggest that changes in miRNA expression might contribute to phenotypic alterations of senescent cells by modulating the expression of key regulatory proteins such as p21(CDKN1A) as well as by targeting genes that are down-regulated in senescent cells such as RARG.
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Affiliation(s)
- Guorong Li
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710, USA
| | - Coralia Luna
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710, USA
| | - Jianming Qiu
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710, USA
| | - David L. Epstein
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710, USA
| | - Pedro Gonzalez
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710, USA
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28
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Firestone GL, Sundar SN. Minireview: modulation of hormone receptor signaling by dietary anticancer indoles. Mol Endocrinol 2009; 23:1940-7. [PMID: 19837944 DOI: 10.1210/me.2009-0149] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Indole-3-carbinol and its diindole condensation product 3-3'-diindolylmethane are dietary phytochemicals that have striking anticarcinogenic properties in human cancer cells. Molecular, cellular, physiological, and clinical studies have documented that both indole-3-carbinol and 3-3'-diindolylmethane have potent endocrine modulating activities through a myriad of mechanisms. The focus of this review is to discuss the evidence that directly links the anticancer actions of these two indole compounds to the control of steroid receptor and growth factor receptor signaling.
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Affiliation(s)
- Gary L Firestone
- Department of Molecular and Cell Biology, The University of California at Berkeley, 94720-3200, USA.
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