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Sun J, Hu JR, Liu CF, Li Y, Wang W, Fu R, Guo M, Wang HL, Pang M. ANKRD49 promotes the metastasis of NSCLC via activating JNK-ATF2/c-Jun-MMP-2/9 axis. BMC Cancer 2023; 23:1108. [PMID: 37964204 PMCID: PMC10644579 DOI: 10.1186/s12885-023-11612-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 11/04/2023] [Indexed: 11/16/2023] Open
Abstract
BACKGROUND Ankyrin repeat domain 49 (ANKRD49) has been found to be highly expressed in multiple cancer including lung adenocarcinoma (LUAD) and lung squamous carcinoma (LUSC). However, the function of ANKRD49 in the pathogenesis of NSCLC still remains elusive. Previously, ANKRD49 has been demonstrated to promote the invasion and metastasis of A549 cells, a LUAD cell line, via activating the p38-ATF-2-MMP2/MMP9 pathways. Considering the heterogeneity of tumor cells, the function and mechanism of ANKRD49 in NSCLC need more NSCLC-originated cells to clarify. METHODS Real-time qPCR was employed to test ANKRD49 expression levels in nine pairs of fresh NSCLC tissues and the corresponding adjacent normal tissues. The function of ANKRD49 was investigated using overexpression and RNA interference assays in lung adenocarcinoma cell line (NCI-H1299) and lung squamous carcinoma cell line (NCI-H1703) through gelatin zymography, cell counting kit-8, colony formation, wound healing, migration and invasion assays mmunoprecipitation was performed to in vitro. Immunoprecipitation was performed to test the interaction of c-Jun and ATF2. Chromatin immunoprecipitation was conducted to assess the transcriptional regulation of ATF2/c-Jun on MMP-2/9. Moreover, the tumorigenicity of ANKRD49 was evaluated in nude mice models and the involved signal molecular was also measured by immunohistochemical method. RESULTS We found that the levels of ANKRD49 in cancerous tissues were higher than those in adjacent normal tissues. in vitro assay showed that ANKRD49 promoted the migration and invasion of NCI-H1299 and NCI-H1703 cells via enhancing the levels of MMP-2 and MMP-9. Furthermore, ANKRD49 elevated phosphorylation of JNK and then activated c-Jun and ATF2 which interact in nucleus to promote the binding of ATF2:c-Jun with the promoter MMP-2 or MMP-9. In vivo assay showed that ANKRD49 promoted lung metastasis of injected-NSCLC cells and the high metastatic rate was positively correlated with the high expression of ANKRD49, MMP-2, MMP-9, p-JNK, p-c-Jun and p-ATF2. CONCLUSION The present study indicated that ANKRD49 accelerated the invasion and metastasis of NSCLC cells via JNK-mediated transcription activation of c-Jun and ATF2 which regulated the expression of MMP-2/MMP-9. The molecular mechanisms of ANKRD49's function is different from those found in A549 cells. The current study is a supplement and improvement to the previous research.
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Affiliation(s)
- Jia Sun
- Department of Pulmonary and Critical Care Medicine, Shanxi Province Key Laboratory of Respiratory Disease, the First Hospital, Shanxi Medical University, NHC Key Laboratory of Pneumoconiosis, Taiyuan, Shanxi, 030001, China
- Department of Laboratorial Medicine, Changzhi Traditional Chinese Medicine Hospital, Changzhi, 046000, China
| | - Jin-Rui Hu
- School of Basic Medicine, Basic Medical Sciences Center, Shanxi Medical University, No. 55 Wenhua Street, Jinzhong, Shanxi, 030600, China
| | - Chao-Feng Liu
- Department of Pulmonary and Critical Care Medicine, Shanxi Province Key Laboratory of Respiratory Disease, the First Hospital, Shanxi Medical University, NHC Key Laboratory of Pneumoconiosis, Taiyuan, Shanxi, 030001, China
| | - Yuan Li
- Department of Respiratory Medicine 1, Shanxi Hospital Affiliated to Cancer Hospital, Shanxi Province Cancer Hospital, Chinese Academy of Medical Sciences, Cancer Hospital Affiliated to Shanxi Medical University, Taiyuan, Shanxi, 030013, China
| | - Wei Wang
- School of Basic Medicine, Basic Medical Sciences Center, Shanxi Medical University, No. 55 Wenhua Street, Jinzhong, Shanxi, 030600, China
| | - Rong Fu
- School of Basic Medicine, Basic Medical Sciences Center, Shanxi Medical University, No. 55 Wenhua Street, Jinzhong, Shanxi, 030600, China
| | - Min Guo
- Laboratory of Animal Center, Shanxi Medical University, Taiyuan, 030001, China
| | - Hai-Long Wang
- School of Basic Medicine, Basic Medical Sciences Center, Shanxi Medical University, No. 55 Wenhua Street, Jinzhong, Shanxi, 030600, China.
| | - Min Pang
- Department of Pulmonary and Critical Care Medicine, Shanxi Province Key Laboratory of Respiratory Disease, the First Hospital, Shanxi Medical University, NHC Key Laboratory of Pneumoconiosis, Taiyuan, Shanxi, 030001, China.
- Department of Pulmonary and Critical Care Medicine, the First Hospital, Shanxi Medical University, No. 85 Jiefang South Road, Taiyuan, Shanxi, 030001, China.
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Wang Y, Su H, Yan M, Zhang L, Tang J, Li Q, Gu X, Gong Q. Interleukin-33 Promotes Cell Survival via p38 MAPK-Mediated Interleukin-6 Gene Expression and Release in Pediatric AML. Front Immunol 2020; 11:595053. [PMID: 33324412 PMCID: PMC7726021 DOI: 10.3389/fimmu.2020.595053] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 10/28/2020] [Indexed: 11/30/2022] Open
Abstract
Acute myeloid leukemia (AML) is a fatal disease characterized by the accumulation of immature myeloid blasts in the bone marrow (BM). Cytokine provide signals for leukemia cells to improve their survival in the BM microenvironment. Previously, we identified interleukin-33 (IL-33) as a promoter of cell survival in a human AML cell line and primary mouse leukemia cells. In this study, we report that the cell surface expression of IL-33–specific receptor, Interleukin 1 Receptor Like 1 (IL1RL1), is elevated in BM cells from AML patients at diagnosis, and the serum level of IL-33 in AML patients is higher than that of healthy donor controls. Moreover, IL-33 levels are found to be positively associated with IL-6 levels in pediatric patients with AML. In vitro, IL-33 treatment increased IL-6 mRNA expression and protein level in BM and peripheral blood (PB) cells from AML patients. Evidence was also provided that IL-33 inhibits cell apoptosis by activating p38 mitogen-activated protein kinase (MAPK) pathway using human AML cell line and AML patient samples. Finally, we confirmed that IL-33 activated IL-6 expression in a manner that required p38 MAPK pathway using clinical AML samples. Taken together, we identified a potential mechanism of IL-33–mediated survival involving p38 MAPK in pediatric AML patients that would facilitate future drug development.
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Affiliation(s)
- Yiqian Wang
- Department of Biochemistry and Molecular Biology, GMU-GIBH Joint School of Life Sciences, Guangzhou Medical University, Guangzhou, China
| | - Haibo Su
- Department of Biochemistry and Molecular Biology, GMU-GIBH Joint School of Life Sciences, Guangzhou Medical University, Guangzhou, China
| | - Muxia Yan
- Department of Hematology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Li Zhang
- Department of Hematology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Jiancheng Tang
- Department of Anesthesiology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Quanxin Li
- Department of Biochemistry and Molecular Biology, GMU-GIBH Joint School of Life Sciences, Guangzhou Medical University, Guangzhou, China
| | - Xiaoqiong Gu
- Department of Blood Transfusion, Clinical Biological Resource Bank and Clinical Lab, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Qing Gong
- Department of Biochemistry and Molecular Biology, GMU-GIBH Joint School of Life Sciences, Guangzhou Medical University, Guangzhou, China
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3
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Watson G, Ronai ZA, Lau E. ATF2, a paradigm of the multifaceted regulation of transcription factors in biology and disease. Pharmacol Res 2017; 119:347-357. [PMID: 28212892 PMCID: PMC5457671 DOI: 10.1016/j.phrs.2017.02.004] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 02/01/2017] [Accepted: 02/02/2017] [Indexed: 01/16/2023]
Abstract
Stringent transcriptional regulation is crucial for normal cellular biology and organismal development. Perturbations in the proper regulation of transcription factors can result in numerous pathologies, including cancer. Thus, understanding how transcription factors are regulated and how they are dysregulated in disease states is key to the therapeutic targeting of these factors and/or the pathways that they regulate. Activating transcription factor 2 (ATF2) has been studied in a number of developmental and pathological conditions. Recent findings have shed light on the transcriptional, post-transcriptional, and post-translational regulatory mechanisms that influence ATF2 function, and thus, the transcriptional programs coordinated by ATF2. Given our current knowledge of its multiple levels of regulation and function, ATF2 represents a paradigm for the mechanistic complexity that can regulate transcription factor function. Thus, increasing our understanding of the regulation and function of ATF2 will provide insights into fundamental regulatory mechanisms that influence how cells integrate extracellular and intracellular signals into a genomic response through transcription factors. Characterization of ATF2 dysfunction in the context of pathological conditions, particularly in cancer biology and response to therapy, will be important in understanding how pathways controlled by ATF2 or other transcription factors might be therapeutically exploited. In this review, we provide an overview of the currently known upstream regulators and downstream targets of ATF2.
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Affiliation(s)
- Gregory Watson
- Department of Tumor Biology and Program in Chemical Biology and Molecular Medicine, H. Lee Moffitt Cancer Center, Tampa, FL, USA
| | - Ze'ev A Ronai
- Tumor Initiation and Maintenance Program, Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA; Technion Integrated Cancer Center, Rappaport Faculty of Medicine, Technion, Haifa, 3109601, Israel
| | - Eric Lau
- Department of Tumor Biology and Program in Chemical Biology and Molecular Medicine, H. Lee Moffitt Cancer Center, Tampa, FL, USA.
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Phosphorylation of JNK Increases in the Cortex of Rat Subjected to Diabetic Cerebral Ischemia. Neurochem Res 2015; 41:787-94. [PMID: 26610380 DOI: 10.1007/s11064-015-1753-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/27/2015] [Accepted: 10/29/2015] [Indexed: 02/08/2023]
Abstract
Previous studies have demonstrated that the c-Jun N-terminal kinase (JNK) pathway plays an important role in inducing neuronal apoptosis following cerebral ischemic injury. JNK signaling pathway in activated during cerebral ischemic injury. It participates in ischemia-induced neuronal apoptosis. However, whether JNK signaling is involved in the process of neuronal apoptosis of diabetes-induced cerebral ischemia is largely unknown. This study was undertaken to evaluate the influence of cerebral ischemia-reperfusion injury on phosphorylation of JNK in diabetic rats. Twenty-four adult streptozotocin induced diabetic and 24 adult non-diabetic rats were randomly subjected to 15 min of forebrain ischemia followed by reperfusion for 0, 1, 3, and 6 h. Sixteen sham-operated diabetic and non-diabetic rats were used as controls. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL). Protein expression of phospho-JNK was examined by immunohistochemistry and Western blot. The numbers of TUNEL-positive cells and phospho-JNK protein expression in the cerebral cortices after 1, 3 and 6 h reperfusion was significantly higher in diabetic rats compared to non-diabetic animals subjected to ischemia and reperfusion (p < 0.05). Western blot analysis showed significantly higher phospho-JNK protein expression in the cerebral cortices of the diabetic rats after 1 and 3 h reperfusion than that was presented in non-diabetic animals subjected to ischemia and reperfusion (p < 0.05). These findings suggest that increased phosphorylation of JNK may be associated with diabetes-enhanced ischemic brain damage.
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Jin H, Kanthasamy A, Harischandra DS, Kondru N, Ghosh A, Panicker N, Anantharam V, Rana A, Kanthasamy AG. Histone hyperacetylation up-regulates protein kinase Cδ in dopaminergic neurons to induce cell death: relevance to epigenetic mechanisms of neurodegeneration in Parkinson disease. J Biol Chem 2014; 289:34743-67. [PMID: 25342743 DOI: 10.1074/jbc.m114.576702] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The oxidative stress-sensitive protein kinase Cδ (PKCδ) has been implicated in dopaminergic neuronal cell death. However, little is known about the epigenetic mechanisms regulating PKCδ expression in neurons. Here, we report a novel mechanism by which the PKCδ gene can be regulated by histone acetylation. Treatment with histone deacetylase (HDAC) inhibitor sodium butyrate (NaBu) induced PKCδ expression in cultured neurons, brain slices, and animal models. Several other HDAC inhibitors also mimicked NaBu. The chromatin immunoprecipitation analysis revealed that hyperacetylation of histone H4 by NaBu is associated with the PKCδ promoter. Deletion analysis of the PKCδ promoter mapped the NaBu-responsive element to an 81-bp minimal promoter region. Detailed mutagenesis studies within this region revealed that four GC boxes conferred hyperacetylation-induced PKCδ promoter activation. Cotransfection experiments and Sp inhibitor studies demonstrated that Sp1, Sp3, and Sp4 regulated NaBu-induced PKCδ up-regulation. However, NaBu did not alter the DNA binding activities of Sp proteins or their expression. Interestingly, a one-hybrid analysis revealed that NaBu enhanced transcriptional activity of Sp1/Sp3. Overexpression of the p300/cAMP-response element-binding protein-binding protein (CBP) potentiated the NaBu-mediated transactivation potential of Sp1/Sp3, but expressing several HDACs attenuated this effect, suggesting that p300/CBP and HDACs act as coactivators or corepressors in histone acetylation-induced PKCδ up-regulation. Finally, using genetic and pharmacological approaches, we showed that NaBu up-regulation of PKCδ sensitizes neurons to cell death in a human dopaminergic cell model and brain slice cultures. Together, these results indicate that histone acetylation regulates PKCδ expression to augment nigrostriatal dopaminergic cell death, which could contribute to the progressive neuropathogenesis of Parkinson disease.
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Affiliation(s)
- Huajun Jin
- From the Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Arthi Kanthasamy
- From the Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Dilshan S Harischandra
- From the Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Naveen Kondru
- From the Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Anamitra Ghosh
- From the Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Nikhil Panicker
- From the Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Vellareddy Anantharam
- From the Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011
| | - Ajay Rana
- the Department of Molecular Pharmacology and Therapeutics, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois 60153, and the Hines Veterans Affairs Medical Center, Hines, Illinois 60141
| | - Anumantha G Kanthasamy
- From the Department of Biomedical Sciences, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa 50011,
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Yun SM, Jeong SJ, Kim JH, Jung JH, Lee HJ, Sohn EJ, Lee MH, Kim SH. Activation of c-Jun N-terminal kinase mediates tanshinone IIA-induced apoptosis in KBM-5 chronic myeloid leukemia cells. Biol Pharm Bull 2013; 36:208-14. [PMID: 23370352 DOI: 10.1248/bpb.b12-00537] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Aim of this study was to identify the molecular mechanisms of tanshinone IIA-induced apoptosis in chronic myelogenous leukemia (CML) cells. Cytotoxicity of tanshinone IIA was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Our data demonstrate that tanshinone IIA induced apoptosis by increasing the sub-G1 DNA contents and DNA fragmentation in KBM-5 CML cell line. In addition, tanshinone IIA significantly reduced mitochondrial membrane potential (MMP), mediated cytochrome c release from mitochondria and activated caspase-3 and 9, indicating mitochondria-dependent apoptosis by tanshinone IIA. Tanshinone IIA attenuated expression of several apoptosis-related proteins such as c-inhibitor of apoptosis protein (IAP) 2, Mcl-1(L) and Bcl-2. Interestingly, although tanshinone IIA notably enhanced the phosphorylation of both c-Jun N-terminal protein kinase (JNK) and p38, JNK inhibitor, but not p38 inhibitor, reversed tanshinone IIA-induced apoptosis. Our findings suggest that tanshinone IIA induces mitochondria-dependent apoptosis via activation of JNK in KBM 5 cells as a potent anti-cancer agent for CML therapy.
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Affiliation(s)
- Sun-Mi Yun
- College of Oriental Medicine, Kyung Hee University, Seoul 130–701, Republic of Korea
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Du E, Li H, Jin S, Hu X, Qiu M, Han R. Evidence that TMEM67 causes polycystic kidney disease through activation of JNK/ERK-dependent pathways. Cell Biol Int 2013; 37:694-702. [PMID: 23456819 DOI: 10.1002/cbin.10081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 02/13/2013] [Indexed: 11/09/2022]
Abstract
TMEM67 mutations are associated with severe autosomal recessive polycystic kidney disease (ARPKD) in both humans and animals. However, the molecular mechanisms underlying the pathogenesis of PKD caused by TMEM67 mutations remain to be determined. We have investigated the possible signalling pathways involved in the pathogenesis of PKD. Overexpression of TMEM67 in human embryonic kidney (HEK293) cells triggered the activation of overall tyrosine phosphorylated proteins, extracellular signal-regulated kinase (ERK) and c-jun N-terminal KINASE (JNK). Activation was suppressed by pharmacological inhibitors of ERK or JNK. Activation of the mammalian target of rapamycin (mTOR) or p70s kinase (S6K) did not occur, although elevated phosphorylation of eIF4E-binding protein 1 (4E-BP1), a target of S6K, was seen. In animal studies, activation of a variety of signalling molecules was linked to ERK, JNK and 4E-BP1. Significant induction of phosphorylation of tyrosine phosphorylated proteins, ERK and 4E-BP1, at different postnatal ages was detected in mutant kidneys of B6C3Fe a/a-bpck mice, a cystic renal disease mouse model caused by TMEM67 loss of function mutation. Based on these in vitro and in vivo observations, we propose that TMEM67 mutations cause PKD through ERK- and JNK-dependent signalling pathways, which may provide novel insight into the therapy of polycystic kidney diseases.
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Affiliation(s)
- E Du
- Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin, China, 300211
| | - Hong Li
- Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, Kentucky 40292
| | - Shunying Jin
- Department of Medicine, School of Medicine, University of Louisville, Louisville, Kentucky 40292
| | - Xuemei Hu
- Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, Kentucky 40292
| | - Mengsheng Qiu
- Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, Kentucky 40292
| | - Ruifa Han
- Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin, China, 300211
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Extracellular matrix proteins modulate antimigratory and apoptotic effects of Doxorubicin. CHEMOTHERAPY RESEARCH AND PRACTICE 2012; 2012:268681. [PMID: 22811904 PMCID: PMC3395309 DOI: 10.1155/2012/268681] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 04/30/2012] [Indexed: 01/13/2023]
Abstract
Anticancer drug resistance is a multifactorial process that includes acquired and de novo drug resistances. Acquired resistance develops during treatment, while de novo resistance is the primary way for tumor cells to escape chemotherapy. Tumor microenvironment has been recently shown to be one of the important factors contributing to de novo resistance and called environment-mediated drug resistance (EMDR). Two forms of EMDR have been described: soluble factor-mediated drug resistance (SFM-DR) and cell adhesion-mediated drug resistance (CAM-DR). Anthracyclines, among the most potent chemotherapeutic agents, are widely used in clinics against hematopoietic and solid tumors. Their main mechanism of action relies on the inhibition of topoisomerase I and/or II and the induction of apoptosis. Beyond this well-known antitumor activity, it has been recently demonstrated that anthracyclines may display potent anti-invasive effects when used at subtoxic concentrations. In this paper, we will describe two particular modes of EMDR by which microenvironment may influence tumor-cell response to one of these anthracyclines, doxorubicin. The first one considers the influence of type I collagen on the antimigratory effect of doxorubicin (CAM-DR). The second considers the protection of tumor cells by thrombospondin-I against doxorubicin-induced apoptosis (SFM-DR).
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Lau E, Ronai ZA. ATF2 - at the crossroad of nuclear and cytosolic functions. J Cell Sci 2012; 125:2815-24. [PMID: 22685333 DOI: 10.1242/jcs.095000] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
An increasing number of transcription factors have been shown to elicit oncogenic and tumor suppressor activities, depending on the tissue and cell context. Activating transcription factor 2 (ATF2; also known as cAMP-dependent transcription factor ATF-2) has oncogenic activities in melanoma and tumor suppressor activities in non-malignant skin tumors and breast cancer. Recent work has shown that the opposing functions of ATF2 are associated with its subcellular localization. In the nucleus, ATF2 contributes to global transcription and the DNA damage response, in addition to specific transcriptional activities that are related to cell development, proliferation and death. ATF2 can also translocate to the cytosol, primarily following exposure to severe genotoxic stress, where it impairs mitochondrial membrane potential and promotes mitochondrial-based cell death. Notably, phosphorylation of ATF2 by the epsilon isoform of protein kinase C (PKCε) is the master switch that controls its subcellular localization and function. Here, we summarize our current understanding of the regulation and function of ATF2 in both subcellular compartments. This mechanism of control of a non-genetically modified transcription factor represents a novel paradigm for 'oncogene addiction'.
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Affiliation(s)
- Eric Lau
- Signal Transduction Program, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd, La Jolla, CA 92130, USA.
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El Btaouri H, Morjani H, Greffe Y, Charpentier E, Martiny L. Role of JNK/ATF-2 pathway in inhibition of thrombospondin-1 (TSP-1) expression and apoptosis mediated by doxorubicin and camptothecin in FTC-133 cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:695-703. [PMID: 21333695 DOI: 10.1016/j.bbamcr.2011.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 02/03/2011] [Accepted: 02/07/2011] [Indexed: 11/25/2022]
Abstract
Our previous studies have shown that camptothecin and doxorubicin triggered ceramide accumulation via de novo synthesis pathway. De novo ceramide generation was responsible for the drug-induced apoptosis through a caspase-3-dependent pathway and a decrease of thrombospondin-1 expression in human thyroid carcinoma FTC-133 cells. Here, we demonstrate that Jun N-terminal kinases play a critical role in camptothecin- and doxorubicin-induced down-regulation of thrombospondin-1 expression: i) de novo ceramide synthesis pathway activates Jun N-terminal kinase 1/2 resulting in activating transcription factor 2 phosphorylation; ii) cell treatment by SP600125, a Jun N-terminal kinase specific inhibitor, strongly reduced activating transcription factor 2 phosphorylation and completely abolished camptothecin and doxorubicin effects; and iii) activating transcription factor 2 expression silencing greatly attenuated camptothecin- and doxorubicin-induced down-regulation of thrombospondin-1 expression and apoptosis. The set of our data established that camptothecin- and doxorubicin-induced activation of Jun N-terminal kinase/activating transcription factor 2 pathway via de novo ceramide synthesis down-regulates thrombospondin-1 expression and apoptosis in human thyroid carcinoma FTC-133 cells. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.
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Affiliation(s)
- Hassan El Btaouri
- Laboratoire SiRMa (Signalisation Cellulaire et Récepteurs Matriciels), UMR-CNRS 6237, UFR Sciences, Reims, France.
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11
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Lee HJ, Jeong CH, Cha JH, Kim KW. PKC-delta inhibitors sustain self-renewal of mouse embryonic stem cells under hypoxia in vitro. Exp Mol Med 2010; 42:294-301. [PMID: 20177147 DOI: 10.3858/emm.2010.42.4.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Under hypoxia, mouse embryonic stem cells (mESCs) lose their self-renewal activity and display an early differentiated morphology mediated by the hypoxia-inducible factor-1 alpha (HIF-1 alpha). Previous studies have demonstrated that PKC-delta is activated by hypoxia and increases the protein stability and transcriptional activity of HIF-1 alpha in human cancer cells. Furthermore, activation of PKC-delta mediates cardiac differentiation of ESCs and hematopoietic stem cells. However, the role of PKC-delta in hypoxia-induced early differentiation of mESCs remains largely unknown. Here, we show the inhibition of PKC-delta activity prevents the early differentiation of mESCs under hypoxia using PKC-delta inhibitors, GF 109203X and rottlerin. Reduction of PKC-delta activity under hypoxia effectively decreased HIF-1 alpha protein levels and substantially recovered the expression of LIF-specific receptor (LIFR) and phosphorylated-STAT3 in mESCs. Furthermore, PKC-delta inhibitors aid to sustain the expression of self-renewal markers and suppress the expression of early differentiation markers in mESCs under hypoxia. Taken together, these results suggest that PKC-delta inhibitors block the early differentiation of mESCs via destabilization of HIF-1 alpha under hypoxia.
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Affiliation(s)
- Hyo-Jong Lee
- Research Institute of Pharmaceutical Sciences, NeuroVascular Coordination Research Center, College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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12
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Moon DO, Kim MO, Kang CH, Lee JD, Choi YH, Kim GY. JNK inhibitor SP600125 promotes the formation of polymerized tubulin, leading to G2/M phase arrest, endoreduplication, and delayed apoptosis. Exp Mol Med 2010; 41:665-77. [PMID: 19478553 DOI: 10.3858/emm.2009.41.9.073] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The JNK inhibitor SP600125 strongly inhibits cell proliferation in many human cancer cells by blocking cell-cycle progression and inducing apoptosis. Despite extensive study, the mechanism by which SP600125 inhibits mitosis-related effects in human leukemia cells remains unclear. We investigated the effects of SP600125 on the inhibition of cell proliferation and the cell cycle, and on microtubule dynamics in vivo and in vitro. Treatment of synchronized leukemia cells with varying concentrations of SP600125 results in significant G2/M cell cycle arrest with elevated p21 levels, phosphorylation of histone H3 within 24 h, and endoreduplication with elevated Cdk2 protein levels after 48 h. SP600125 also induces significant abnormal microtubule dynamics in vivo. High concentrations of SP600125 (200 microM) were required to disorganize microtubule polymerization in vitro. Additionally, SP600125- induced delayed apoptosis and cell death was accompanied by significant poly ADP-ribose polymerase (PARP) cleavage and caspase-3 activity in the late phase (at 72 h). Endoreduplication showed a greater increase in ectopic Bcl-2-expressing U937 cells at 72 h than in wild-type U937 cells without delayed apoptosis. These results indicate that Bcl-2 suppresses apoptosis and SP600125-induced G2/M arrest and endoreduplication. Therefore, we suggest that SP600125 induces mitotic arrest by inducing abnormal spindle microtubule dynamics.
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Affiliation(s)
- Dong Oh Moon
- Laboratory of Immunobiology, Department of Marine Life Sciences, Jeju National University and, Jeju Regional Cancer Center, Jeju 690-756, Korea
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Seldeen KL, McDonald CB, Deegan BJ, Bhat V, Farooq A. DNA plasticity is a key determinant of the energetics of binding of Jun-Fos heterodimeric transcription factor to genetic variants of TGACGTCA motif. Biochemistry 2010; 48:12213-22. [PMID: 19921846 DOI: 10.1021/bi901392k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The Jun-Fos heterodimeric transcription factor is a target of a diverse array of signaling cascades that initiate at the cell surface and converge in the nucleus and ultimately result in the expression of genes involved in a multitude of cellular processes central to health and disease. Here, using isothermal titration calorimetry in conjunction with circular dichroism, we report the effect of introducing single nucleotide variations within the TGACGTCA canonical motif on the binding of bZIP domains of Jun-Fos heterodimer to DNA. Our data reveal that the Jun-Fos heterodimer exhibits differential energetics in binding to such genetic variants in the physiologically relevant micromolar to submicromolar range with the TGACGTCA canonical motif affording the highest affinity. Although binding energetics are largely favored by enthalpic forces and accompanied by entropic penalty, neither the favorable enthalpy nor the unfavorable entropy correlates with the overall free energy of binding in agreement with the enthalpy-entropy compensation phenomenon widely observed in biological systems. However, a number of variants including the TGACGTCA canonical motif bind to the Jun-Fos heterodimer with high affinity through having overcome such enthalpy-entropy compensation barrier, arguing strongly that better understanding of the underlying invisible forces driving macromolecular interactions may be the key to future drug design. Our data also suggest that the Jun-Fos heterodimer has a preference for binding to TGACGTCA variants with higher AT content, implying that the DNA plasticity may be an important determinant of protein-DNA interactions. This notion is further corroborated by the observation that the introduction of genetic variations within the TGACGTCA motif allows it to sample a much greater conformational space. Taken together, these new findings further our understanding of the role of DNA sequence and conformation on protein-DNA interactions in thermodynamic terms.
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Affiliation(s)
- Kenneth L Seldeen
- Department of Biochemistry and Molecular Biology and USylvester Braman Family Breast Cancer Institute, Leonard Miller School of Medicine, University of Miami, Miami, Florida 33136, USA
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Abstract
Emerging evidence indicates that suppression of protein kinase C (PKC) renders the susceptibility of cells expressing mutated ras to apoptosis. Although the effort has been made, the underlying molecular mechanisms are not fully understood. In this study, using small hairpin RNAs (shRNAs) or PKC inhibitor, we show that the concurrent suppression of PKC-alpha and beta induces cells ectopically expressing v-ras to undergo apoptosis. In this apoptotic process, PKC-delta is upregulated and translocated from the cytosol to the nucleus. The activated PKC-delta associates with and phosphorylates p73 to initiate apoptosis. In this apoptotic process, Akt seems to be downstream of oncogenic Ras. Moreover, overexpression of PKC-delta, without co-suppression of PKC-alpha and beta, is not apoptotic to the cells, suggesting that PKC-delta and PKC-alpha/beta function oppositely to facilitate cells harboring v-ras to survive. Thus, our study shows that PKC-alpha and beta are necessary for sustaining the homeostasis in cells containing a hyperactive Ras. The abrogation of these two isoforms switches on the p73-regulated apoptotic machinery through the activation of PKC-delta.
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