51
|
Wilson BAP, Alam MS, Guszczynski T, Jakob M, Shenoy SR, Mitchell CA, Goncharova EI, Evans JR, Wipf P, Liu G, Ashwell JD, O'Keefe BR. Discovery and Characterization of a Biologically Active Non-ATP-Competitive p38 MAP Kinase Inhibitor. ACTA ACUST UNITED AC 2015; 21:277-89. [PMID: 26538432 DOI: 10.1177/1087057115615518] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 10/09/2015] [Indexed: 01/06/2023]
Abstract
Mitogen-activated protein kinase (MAPK) p38 is part of a broad and ubiquitously expressed family of MAPKs whose activity is responsible for mediating an intracellular response to extracellular stimuli through a phosphorylation cascade. p38 is central to this signaling node and is activated by upstream kinases while being responsible for activating downstream kinases and transcription factors via phosphorylation. Dysregulated p38 activity is associated with numerous autoimmune disorders and has been implicated in the progression of several types of cancer. A number of p38 inhibitors have been tested in clinical trials, with none receiving regulatory approval. One characteristic shared by all of the compounds that failed clinical trials is that they are all adenosine triphosphate (ATP)-competitive p38 inhibitors. Seeing this lack of mechanistic diversity as an opportunity, we screened ~32,000 substances in search of novel p38 inhibitors. Among the inhibitors discovered is a compound that is both non-ATP competitive and biologically active in cell-based models for p38 activity. This is the first reported discovery of a non-ATP-competitive p38 inhibitor that is active in cells and, as such, may enable new pharmacophore designs for both therapeutic and basic research to better understand and exploit non-ATP-competitive inhibitors of p38 activity.
Collapse
Affiliation(s)
- Brice A P Wilson
- Molecular Targets Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Muhammad S Alam
- Laboratory of Immune Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Tad Guszczynski
- Molecular Targets Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Michal Jakob
- Department of Biochemistry, Faculty of Chemistry, Wrocław University of Technology, Wrocław, Poland
| | - Shilpa R Shenoy
- Molecular Targets Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Carter A Mitchell
- Molecular Targets Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Ekaterina I Goncharova
- Molecular Targets Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA Data Management Services, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Jason R Evans
- Data Management Services, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Gang Liu
- Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Tsinghua-Peking Center for Life Sciences and Department of Pharmacology and Pharmaceutical Sciences, School of Medicine, Tsinghua University, Beijing China
| | - Jonathan D Ashwell
- Laboratory of Immune Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Barry R O'Keefe
- Molecular Targets Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA Natural Products Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| |
Collapse
|
52
|
Zeng C, Xu JN, Zhou Y, Yang HX, Zhou YF, Xue Q. C-Jun NH2-Terminal Kinase and p38 Inhibition Suppresses Prostaglandin E2-Stimulated Aromatase and Estrogen Receptor Levels in Human Endometriosis. J Clin Endocrinol Metab 2015; 100:E1404-14. [PMID: 26394174 DOI: 10.1210/jc.2015-2031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Endometriosis is an estrogen-dependent disease. P38 and C-jun NH2-terminal kinase (JNK) inhibitors may have a therapeutic effect on endometriosis through regulation of prostaglandin E2 (PGE2)-induced estrogen metabolism. OBJECTIVE The objective of this study was to determine whether the activated MAPKs signaling pathway observed in human ectopic endometrial stromal cells (ESCs) from ovarian endometriomas influences levels of aromatase and estrogen receptor β (ERβ) protein regulated by PGE2. In turn, the effects of inhibiting MAPKs in the presence of PGE2 on estrogen production were investigated in vitro and in vivo. RESULTS Expression of aromatase and ERβ regulated by PGE2 were much higher in ESCs than eutopic ESCs from the same person. Activation of p38, JNK, ERK 1/2 and ERK 5 MAPKs by PGE2 were observed in ESCs, where PGE2-stimulated aromatase and ERβ expression mainly through p38 and JNK pathway. P38 and JNK inhibition or small interfering RNA knockdown blocked PGE2-induced aromatase and ERβ expression. PGE2 enhanced binding of downstream p38 and JNK transcription factors activating transcription factor-2 and c-Jun to aromatase and ERB promoter regions in ESCs. Moreover, treatment of endometriosis xenografts with inhibitors of p38 and JNK abrogated PGE2-amplified estradiol synthesis and xenograft growth. CONCLUSIONS PGE2 activates p38 and JNK signaling pathways, further stimulating c-Jun and activating transcription factor-2 binding to aromatase and ERB promoter regions with elevated estradiol production. Inhibition of JNK and P38 may be a potential method of treating human endometriosis.
Collapse
Affiliation(s)
- Cheng Zeng
- Department of Obstetrics and Gynecology (C.Z., J.-n.X., Y.Z., H.-x.Y., Y.-f.Z., Q.X.), Peking University First Hospital, Beijing, 100034, P. R. China
| | - Jia-Ning Xu
- Department of Obstetrics and Gynecology (C.Z., J.-n.X., Y.Z., H.-x.Y., Y.-f.Z., Q.X.), Peking University First Hospital, Beijing, 100034, P. R. China
| | - Yan Zhou
- Department of Obstetrics and Gynecology (C.Z., J.-n.X., Y.Z., H.-x.Y., Y.-f.Z., Q.X.), Peking University First Hospital, Beijing, 100034, P. R. China
| | - Hui-Xia Yang
- Department of Obstetrics and Gynecology (C.Z., J.-n.X., Y.Z., H.-x.Y., Y.-f.Z., Q.X.), Peking University First Hospital, Beijing, 100034, P. R. China
| | - Ying-Fang Zhou
- Department of Obstetrics and Gynecology (C.Z., J.-n.X., Y.Z., H.-x.Y., Y.-f.Z., Q.X.), Peking University First Hospital, Beijing, 100034, P. R. China
| | - Qing Xue
- Department of Obstetrics and Gynecology (C.Z., J.-n.X., Y.Z., H.-x.Y., Y.-f.Z., Q.X.), Peking University First Hospital, Beijing, 100034, P. R. China
| |
Collapse
|
53
|
Dong Y, Kimura Y, Ito T, Velayo C, Sato T, Sugibayashi R, Funamoto K, Hitomi K, Iida K, Endo M, Sato N, Yaegashi N. Vaginal LPS changed gene transcriptional regulation response to ischemic reperfusion and increased vulnerability of fetal brain hemorrhage. Biochem Biophys Res Commun 2015; 468:228-33. [PMID: 26523514 DOI: 10.1016/j.bbrc.2015.10.125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 10/24/2015] [Indexed: 01/09/2023]
Abstract
During pregnancy, both ischemic reperfusion and bacterial agent LPS are known risk factors for fetal brain damage. However, there is a lack of evidence to explain whether vaginal LPS affects the fetus response to ischemic reperfusion. Here we reported that there was more than 2 folds higher vulnerability of fetal brain hemorrhage response to ischemic reperfusion when mother mouse was treated with vaginal LPS. As our previously reported, ischemic reperfusion induces P53-dependent fetal brain damage was based on a molecular mechanism: the transcriptional pattern was changed from HIF-1alpha-dependent to P53-dependent immediately. In the present work, only with vaginal LPS precondition, phosphorylation of activated transcriptional factor (ATF) 2 at Thr71 appeared in response to ischemic reperfusion. Moreover, this phosphorylation was completely blocked by pre-treatment with a P53 inhibitor, pifithrin-α. We concluded that vaginal LPS precondition trigged the p53-dependent phosphorylation of ATF2 in response to ischemic reperfusion, which played an important role of increasing vulnerability to hemorrhage in fetus.
Collapse
Affiliation(s)
- Yupeng Dong
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan.
| | - Yoshitaka Kimura
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan; Department of Obstetrics & Gynecology, Tohoku University Hospital, Sendai, Japan
| | - Takuya Ito
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Clarissa Velayo
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Takafumi Sato
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Rika Sugibayashi
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Kiyoe Funamoto
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Kudo Hitomi
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Keita Iida
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Miyuki Endo
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Naoaki Sato
- Advanced Interdisciplinary Biomedical Engineering, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Nobuo Yaegashi
- Department of Obstetrics & Gynecology, Tohoku University Hospital, Sendai, Japan
| |
Collapse
|
54
|
Huang Q, Du X, He X, Yu Q, Hu K, Breitwieser W, Shen Q, Ma S, Li M. JNK-mediated activation of ATF2 contributes to dopaminergic neurodegeneration in the MPTP mouse model of Parkinson's disease. Exp Neurol 2015; 277:296-304. [PMID: 26515688 DOI: 10.1016/j.expneurol.2015.10.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 10/02/2015] [Accepted: 10/24/2015] [Indexed: 12/29/2022]
Abstract
The c-Jun N-terminal kinase (JNK)/c-Jun pathway is a known critical regulator of dopaminergic neuronal death in Parkinson's disease (PD) and is considered a potential target for neuroprotective therapy. However, whether JNK is activated within dopaminergic neurons remains controversial, and whether JNK acts through downstream effectors other than c-Jun to promote dopaminergic neuronal death remains unclear. In this study, we confirm that JNK but not p38 is activated in dopaminergic neurons after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxication. Furthermore, within the dopaminergic neurons of the substantia nigra in MPTP-treated mice, JNK2/3 phosphorylates threonine 69 (Thr69) of Activating transcription factor-2 (ATF2), a transcription factor of the ATF/CREB family, whereas the phosphorylation of Thr71 is constitutive and remains unchanged. The increased phosphorylation of ATF2 on Thr69 by JNK in the MPTP mouse model suggests a functional relationship between the transcriptional activation of ATF2 and dopaminergic neuron death. By using dopaminergic neuron-specific conditional ATF2 mutant mice, we found that either partial or complete deletion of the ATF2 DNA-binding domain in dopaminergic neurons markedly alleviates the MPTP-induced dopaminergic neurodegeneration, indicating that the activation of ATF2 plays a detrimental role in neuropathogenesis in PD. Taken together, our findings demonstrate that JNK-mediated ATF2 activation contributes to dopaminergic neuronal death in an MPTP model of PD.
Collapse
Affiliation(s)
- Qiaoying Huang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China
| | - Xiaoxiao Du
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China
| | - Xin He
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China
| | - Qing Yu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China
| | - Kunhua Hu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China
| | - Wolfgang Breitwieser
- Cell Regulation Department, CRUK Manchester Institute, Wilmslow Road, Manchester M20 4BX, United Kingdom
| | - Qingyu Shen
- Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China; Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou 510120, China
| | - Shanshan Ma
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China.
| | - Mingtao Li
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China; Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, China.
| |
Collapse
|
55
|
Faid I, Al-Hussaini H, Kilarkaje N. Resveratrol alleviates diabetes-induced testicular dysfunction by inhibiting oxidative stress and c-Jun N-terminal kinase signaling in rats. Toxicol Appl Pharmacol 2015; 289:482-94. [PMID: 26499206 DOI: 10.1016/j.taap.2015.10.012] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 10/16/2015] [Accepted: 10/19/2015] [Indexed: 12/18/2022]
Abstract
Diabetes adversely affects reproductive functions in humans and animals. The present study investigated the effects of Resveratrol on diabetes-induced alterations in oxidative stress, c-Jun N-terminal kinase (JNK) signaling and apoptosis in the testis. Adult male Wistar rats (13-15 weeks; n=6/group) were segregated into 1) normal control, 2) Resveratrol-treated (5mg/kg; ip; given during last 3 weeks), 3) Streptozotocin-induced diabetic and, 4) Resveratrol-treated diabetic groups, and euthanized on day 42 after the confirmation of diabetes. Resveratrol did not normalize blood glucose levels in diabetic rats. Resveratrol supplementation recovered diabetes-induced decreases in reproductive organ weights, sperm count and motility, intra-testicular levels of superoxide dismutase, catalase, and glutathione peroxidase and an increase in 4-hydroxynonenal activities (P<0.05). Resveratrol also recovered diabetes-induced increases in JNK signaling pathway proteins, namely, ASK1 (apoptosis signal-regulating kinase 1), JNKs (46 and 54 kDa isoforms) and p-JNK to normal control levels (P<0.05). Interestingly, the expression of a down-stream target of ASK1, MKK4 (mitogen-activated protein kinase kinase 4) and its phosphorylated form (p-MKK4) did not change in experimental groups. Resveratrol inhibited diabetes-induced increases in AP-1 (activator protein-1) components, c-Jun and ATF2 (activating transcription factor 2), but not their phosphorylated forms, to normal control levels (P<0.05). Further, Resveratrol inhibited diabetes-induced increase in cleaved-caspase-3 to normal control levels. In conclusion, Resveratrol alleviates diabetes-induced apoptosis in testis by modulating oxidative stress, JNK signaling pathway and caspase-3 activities, but not by inhibiting hyperglycemia, in rats. These results suggest that Resveratrol supplementation may be a useful strategy to treat diabetes-induced testicular dysfunction.
Collapse
Affiliation(s)
- Iman Faid
- Department of Anatomy, Faculty of Medicine, Kuwait University, Kuwait
| | - Heba Al-Hussaini
- Department of Anatomy, Faculty of Medicine, Kuwait University, Kuwait
| | | |
Collapse
|
56
|
Barkeer S, Guha N, Hothpet V, Saligrama Adavigowda D, Hegde P, Padmanaban A, Yu LG, Swamy BM, Inamdar SR. Molecular mechanism of anticancer effect of Sclerotium rolfsii lectin in HT29 cells involves differential expression of genes associated with multiple signaling pathways: A microarray analysis. Glycobiology 2015; 25:1375-91. [PMID: 26347523 DOI: 10.1093/glycob/cwv067] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 08/17/2015] [Indexed: 12/16/2022] Open
Abstract
Sclerotium rolfsii lectin (SRL) is a lectin isolated from fungus S. rolfsii and has high binding specificity toward the oncofetal Thomsen-Friedenreich carbohydrate antigen (Galβ1-3GalNAc-α-O-Ser/Thr, T or TF), which is expressed in more than 90% of human cancers. Our previous studies have shown that binding of SRL to human colon, breast and ovarian cancer cells induces cell apoptosis in vitro and suppresses tumor growth in vivo. This study investigated the SRL-mediated cell signaling in human colon cancer HT29 cells by mRNA and miRNA microarrays. It was found that SRL treatment results in altered expression of several hundred molecules including mitogen-activated protein kinase (MAPK) and c-JUN-associated, apoptosis-associated and cell cycle and DNA replication-associated signaling molecules. Pathway analysis using GeneSpring 12.6.1 revealed that SRL treatment induces changes of MAPK and c-JUN-associated signaling pathways as early as 2 h while changes of cell cycle, DNA replication and apoptosis pathways were significantly affected only after 24 h. A significant change of cell miRNA expression was also observed after 12 h treatment of the cells with SRL. These changes were further validated by quantitative real time polymerase chain reaction and immunoblotting. This study thus suggests that the presence of SRL affects multiple signaling pathways in cancer cells with early effects on cell proliferation pathways associated with MAPK and c-JUN, followed by miRNA-associated cell activity and apoptosis. This provides insight information into the molecular mechanism of the anticancer activity of this fungal lectin.
Collapse
Affiliation(s)
- Srikanth Barkeer
- Department of Studies in Biochemistry, Karnatak University, Dharwad 580 003, India
| | - Nilanjan Guha
- Agilent Technologies India Pvt. Ltd, Bangalore 560048, India
| | | | | | - Prajna Hegde
- Department of Studies in Biochemistry, Karnatak University, Dharwad 580 003, India
| | | | - Lu-Gang Yu
- Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| | - Bale M Swamy
- Department of Studies in Biochemistry, Karnatak University, Dharwad 580 003, India Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| | - Shashikala R Inamdar
- Department of Studies in Biochemistry, Karnatak University, Dharwad 580 003, India Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| |
Collapse
|
57
|
Role of the Exocyst Complex Component Sec6/8 in Genomic Stability. Mol Cell Biol 2015; 35:3633-45. [PMID: 26283729 DOI: 10.1128/mcb.00768-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 08/07/2015] [Indexed: 11/20/2022] Open
Abstract
The exocyst is a heterooctomeric complex well appreciated for its role in the dynamic assembly of specialized membrane domains. Accumulating evidence indicates that this macromolecular machine also serves as a physical platform that coordinates regulatory cascades supporting biological systems such as host defense signaling, cell fate, and energy homeostasis. The isolation of multiple components of the DNA damage response (DDR) as exocyst-interacting proteins, together with the identification of Sec8 as a suppressor of the p53 response, suggested functional interactions between the exocyst and the DDR. We found that exocyst perturbation resulted in resistance to ionizing radiation (IR) and accelerated resolution of DNA damage. This occurred at the expense of genomic integrity, as enhanced recombination frequencies correlated with the accumulation of aberrant chromatid exchanges. Sec8 perturbation resulted in the accumulation of ATF2 and RNF20 and the promiscuous accumulation of DDR-associated chromatin marks and Rad51 repairosomes. Thus, the exocyst supports DNA repair fidelity by limiting the formation of repair chromatin in the absence of DNA damage.
Collapse
|
58
|
|
59
|
Transcriptomic Analysis of mRNAs in Human Monocytic Cells Expressing the HIV-1 Nef Protein and Their Exosomes. BIOMED RESEARCH INTERNATIONAL 2015; 2015:492395. [PMID: 25961023 PMCID: PMC4413250 DOI: 10.1155/2015/492395] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 12/16/2014] [Indexed: 02/06/2023]
Abstract
The Nef protein of human immunodeficiency virus (HIV) promotes viral replication and progression to AIDS. Besides its well-studied effects on intracellular signaling, Nef also functions through its secretion in exosomes, which are nanovesicles containing proteins, microRNAs, and mRNAs and are important for intercellular communication. Nef expression enhances exosome secretion and these exosomes can enter uninfected CD4 T cells leading to apoptotic death. We have recently reported the first miRNome analysis of exosomes secreted from Nef-expressing U937monocytic cells. Here we show genome-wide transcriptome analysis of Nef-expressing U937 cells and their exosomes. We identified four key mRNAs preferentially retained in Nef-expressing cells; these code for MECP2, HMOX1, AARSD1, and ATF2 and are important for chromatin modification and gene expression. Interestingly, their target miRNAs are exported out in exosomes. We also identified three key mRNAs selectively secreted in exosomes from Nef-expressing U937 cells and their corresponding miRNAs being preferentially retained in cells. These are AATK, SLC27A1, and CDKAL and are important in apoptosis and fatty acid transport. Thus, our study identifies selectively expressed mRNAs in Nef-expressing U937 cells and their exosomes and supports a new mode on intercellular regulation by the HIV-1 Nef protein.
Collapse
|
60
|
Hu CD, Choo R, Huang J. Neuroendocrine differentiation in prostate cancer: a mechanism of radioresistance and treatment failure. Front Oncol 2015; 5:90. [PMID: 25927031 PMCID: PMC4396194 DOI: 10.3389/fonc.2015.00090] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Accepted: 03/26/2015] [Indexed: 12/20/2022] Open
Abstract
Neuroendocrine differentiation (NED) in prostate cancer is a well-recognized phenotypic change by which prostate cancer cells transdifferentiate into neuroendocrine-like (NE-like) cells. NE-like cells lack the expression of androgen receptor and prostate specific antigen, and are resistant to treatments. In addition, NE-like cells secrete peptide hormones and growth factors to support the growth of surrounding tumor cells in a paracrine manner. Accumulated evidence has suggested that NED is associated with disease progression and poor prognosis. The importance of NED in prostate cancer progression and therapeutic response is further supported by the fact that therapeutic agents, including androgen-deprivation therapy, chemotherapeutic agents, and radiotherapy, also induce NED. We will review the work supporting the overall hypothesis that therapy-induced NED is a mechanism of resistance to treatments, as well as discuss the relationship between therapy-induced NED and therapy-induced senescence, epithelial-to-mesenchymal transition, and cancer stem cells. Furthermore, we will use radiation-induced NED as a model to explore several NED-based targeting strategies for development of novel therapeutics. Finally, we propose future studies that will specifically address therapy-induced NED in the hope that a better treatment regimen for prostate cancer can be developed.
Collapse
Affiliation(s)
- Chang-Deng Hu
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University Center for Cancer Research, Purdue University , West Lafayette, IN , USA
| | - Richard Choo
- Department of Radiation Oncology, Mayo Clinic , Rochester, MN , USA
| | - Jiaoti Huang
- Department of Pathology, David Geffen School of Medicine at UCLA , Los Angeles, CA , USA
| |
Collapse
|
61
|
Liu Z, Luo Q, Guo C. Bim and VDAC1 are hierarchically essential for mitochondrial ATF2 mediated cell death. Cancer Cell Int 2015; 15:34. [PMID: 25852302 PMCID: PMC4387661 DOI: 10.1186/s12935-015-0188-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 03/20/2015] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND ATF2 mediated cytochrome c release is the formation of a channel with some unknown factors larger than that of the individual proteins. BHS-only proteins (BH3s), such as Bim, could induce BAX and VDAC, forming a new channel. According to this facts, we can speculated that there is possible signal relationship with BH3s and ATF2, which is associated with mitochondrial-based death programs. METHODS The growth inhibitory effects of mitochondrial ATF2 were tested in cancer cell lines B16F10, A549, EG7, and LL2. Apoptosis was measured by flow cytometry. The effects of ATF2 and levels of apoptosis regulatory proteins were measured by Western blotting. The interaction of proteins were evaluated by immunoprecipitation analysis. The in vivo antitumor activity of mitochondrial ATF2 were tested in xenograft B16F10 models. RESULTS Genotoxic stress enabled mitochondrial ATF2 accumulation, perturbing the HK1-VDAC1 complex, increasing mitochondrial permeability, and promoting apoptosis. ATF2 inhibition strongly reduced the conformational activation of Bim, suggesting that Bim acts downstream of ATF2. Although Bim downregulation had no effect on ATF2 activation, Bim knockdown abolished VDAC1 activation; the failure of VDAC1 activation in Bim-depleted cells could be reversed by the BH3-only protein mimic ABT-737. We also demonstrate that silencing of ATF2 in B16F10 cells increases both the incidence and prevalence of tumor xenografts in vivo, whereas stably mitochondrial ATF2 transfection inhibited B16F10 tumor xenografts growth. CONCLUSIONS Altogether, these results show that ATF2 is a component of the apoptosis machinery that involves a hierarchical contribution of ATF2, Bim, and VDAC1. Our data offer new insight into the mechanism of mitochondrial ATF2 in mitochondrial apoptosis.
Collapse
Affiliation(s)
- Zhaoyun Liu
- Laboratory of Surgery, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2nd Rd, Chongqing, 400014 P. R. China
| | - Qianfu Luo
- Laboratory of Surgery, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2nd Rd, Chongqing, 400014 P. R. China
| | - Chunbao Guo
- Laboratory of Surgery, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2nd Rd, Chongqing, 400014 P. R. China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, P. R. China
| |
Collapse
|
62
|
Nam EH, Lee Y, Moon B, Lee JW, Kim S. Twist1 and AP-1 cooperatively upregulate integrin α5 expression to induce invasion and the epithelial–mesenchymal transition. Carcinogenesis 2015; 36:327-37. [DOI: 10.1093/carcin/bgv005] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
|
63
|
Cdk1-mediated phosphorylation of human ATF7 at Thr-51 and Thr-53 promotes cell-cycle progression into M phase. PLoS One 2014; 9:e116048. [PMID: 25545367 PMCID: PMC4278844 DOI: 10.1371/journal.pone.0116048] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 11/30/2014] [Indexed: 12/22/2022] Open
Abstract
Activating transcription factor 2 (ATF2) and its homolog ATF7 are phosphorylated at Thr-69/Thr-71 and at Thr-51/Thr-53, respectively, by stress-activated MAPKs regulating their transcriptional functions in G1 and S phases. However, little is known about the role of ATF2 and ATF7 in G2/M phase. Here, we show that Cdk1-cyclin B1 phosphorylates ATF2 at Thr-69/Thr-71 and ATF7 at Thr-51/Thr-53 from early prophase to anaphase in the absence of any stress stimulation. Knockdown of ATF2 or ATF7 decreases the rate of cell proliferation and the number of cells in M-phase. In particular, the knockdown of ATF7 severely inhibits cell proliferation and G2/M progression. The inducible expression of a mitotically nonphosphorylatable version of ATF7 inhibits G2/M progression despite the presence of endogenous ATF7. We also show that mitotic phosphorylation of ATF7 promotes the activation of Aurora kinases, which are key enzymes for early mitotic events. These results suggest that the Cdk1-mediated phosphorylation of ATF7 facilitates G2/M progression, at least in part, by enabling Aurora signaling.
Collapse
|
64
|
Jones A, Kainz D, Khan F, Lee C, Carrithers MD. Human macrophage SCN5A activates an innate immune signaling pathway for antiviral host defense. J Biol Chem 2014; 289:35326-40. [PMID: 25368329 PMCID: PMC4271219 DOI: 10.1074/jbc.m114.611962] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 10/21/2014] [Indexed: 12/20/2022] Open
Abstract
Pattern recognition receptors contain a binding domain for pathogen-associated molecular patterns coupled to a signaling domain that regulates transcription of host immune response genes. Here, a novel mechanism that links pathogen recognition to channel activation and downstream signaling is proposed. We demonstrate that an intracellular sodium channel variant, human macrophage SCN5A, initiates signaling and transcription through a calcium-dependent isoform of adenylate cyclase, ADCY8, and the transcription factor, ATF2. Pharmacological stimulation with a channel agonist or treatment with cytoplasmic poly(I:C), a mimic of viral dsRNA, activates this pathway to regulate expression of SP100-related genes and interferon β. Electrophysiological analysis reveals that the SCN5A variant mediates nonselective outward currents and a small, but detectable, inward current. Intracellular poly(I:C) markedly augments an inward voltage-sensitive sodium current and inhibits the outward nonselective current. These results suggest human macrophage SCN5A initiates signaling in an innate immune pathway relevant to antiviral host defense. It is postulated that SCN5A is a novel pathogen sensor and that this pathway represents a channel activation-dependent mechanism of transcriptional regulation.
Collapse
MESH Headings
- Activating Transcription Factor 2/genetics
- Activating Transcription Factor 2/immunology
- Activating Transcription Factor 2/metabolism
- Adenylyl Cyclases/genetics
- Adenylyl Cyclases/immunology
- Adenylyl Cyclases/metabolism
- Animals
- Antigens, Nuclear/genetics
- Antigens, Nuclear/immunology
- Antigens, Nuclear/metabolism
- Antiviral Agents/pharmacology
- Autoantigens/genetics
- Autoantigens/immunology
- Autoantigens/metabolism
- Blotting, Western
- Cells, Cultured
- Cyclic AMP/immunology
- Cyclic AMP/metabolism
- Gene Expression Profiling
- HEK293 Cells
- Herpesvirus 1, Human/immunology
- Herpesvirus 1, Human/physiology
- Host-Pathogen Interactions/immunology
- Humans
- Immunity, Innate/genetics
- Immunity, Innate/immunology
- Interferon-beta/genetics
- Interferon-beta/immunology
- Interferon-beta/metabolism
- Macrophages/immunology
- Macrophages/metabolism
- Macrophages/virology
- Mice, Inbred C57BL
- Mice, Transgenic
- Microscopy, Fluorescence
- NAV1.5 Voltage-Gated Sodium Channel/genetics
- NAV1.5 Voltage-Gated Sodium Channel/immunology
- NAV1.5 Voltage-Gated Sodium Channel/metabolism
- Oligonucleotide Array Sequence Analysis
- Poly I-C/pharmacology
- Protein Binding/immunology
- RNA Interference
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Signal Transduction/immunology
Collapse
Affiliation(s)
- Alexis Jones
- From the Department of Neurology and Program in Cellular and Molecular Pathology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706 and
| | - Danielle Kainz
- From the Department of Neurology and Program in Cellular and Molecular Pathology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706 and
| | - Faatima Khan
- From the Department of Neurology and Program in Cellular and Molecular Pathology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706 and
| | - Cara Lee
- From the Department of Neurology and Program in Cellular and Molecular Pathology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706 and
| | - Michael D Carrithers
- From the Department of Neurology and Program in Cellular and Molecular Pathology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706 and the William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin 53705
| |
Collapse
|
65
|
Keklikoglu N, Akinci S. ATF-2 immunoreactivity in post-mitotic and terminally differentiated human odontoblasts. Med Mol Morphol 2014; 48:164-8. [PMID: 25417007 DOI: 10.1007/s00795-014-0092-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 11/06/2014] [Indexed: 10/24/2022]
Abstract
Activating transcription factor 2 (ATF-2/CRE-BP1; cAMP-responsive element binding protein 1) is a member of nuclear transcription factor activator protein-1 (AP-1) family. AP-1 regulates cellular processes including growth, proliferation, differentiation and apoptosis. However, biological relationship of cellular process to each member of the AP-1 family is not clear yet. The objective of the present study was to compare the ATF-2 immunoreactivity in the post-mitotic and terminally differentiated odontoblasts and in the pulpal fibroblasts which can be divided by mitosis when required. Fibroblasts at various stages of differentiation co-exist in the human dental pulp. ATF-2 was investigated immunohistochemically in 20 permanent human teeth. According to the findings obtained, the mean percentage of ATF-2 positive cells was 68.5 ± 19.2% in the odontoblasts and 22.8 ± 13.7% in the pulpal fibroblasts. The comparison of ATF-2 positivity revealed a statistically significant difference between odontoblasts and pulpal fibroblasts. These findings have suggested that ATF-2 is more associated with cell survival rather than cell proliferation, and revealed much of effectiveness in maintaining terminal differentiation than the various differentiation stages of the cells.
Collapse
Affiliation(s)
- Nurullah Keklikoglu
- Division of Basic Sciences, Department of Histology and Embryology, Faculty of Dentistry, Istanbul University, Capa, Istanbul, Turkey.
| | - Sevtap Akinci
- Division of Basic Sciences, Department of Histology and Embryology, Faculty of Dentistry, Istanbul University, Capa, Istanbul, Turkey
| |
Collapse
|
66
|
Rudraraju B, Droog M, Abdel-Fatah TMA, Zwart W, Giannoudis A, Malki MI, Moore D, Patel H, Shaw J, Ellis IO, Chan S, Brooke GN, Nevedomskaya E, Lo Nigro C, Carroll J, Coombes RC, Bevan C, Ali S, Palmieri C. Phosphorylation of activating transcription factor-2 (ATF-2) within the activation domain is a key determinant of sensitivity to tamoxifen in breast cancer. Breast Cancer Res Treat 2014; 147:295-309. [PMID: 25141981 DOI: 10.1007/s10549-014-3098-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 08/07/2014] [Indexed: 12/31/2022]
Abstract
Activating transcription factor-2 (ATF-2) has been implicated as a tumour suppressor in breast cancer (BC). c-JUN N-terminal kinase (JNK) and p38 MAPK phosphorylate ATF-2 within the activation domain (AD), which is required for its transcriptional activity. To date, the role of ATF-2 in determining response to endocrine therapy has not been explored. Effects of ATF-2 loss in the oestrogen receptor (ER)-positive luminal BC cell line MCF7 were explored, as well as its role in response to tamoxifen treatment. Genome-wide chromatin binding patterns of ATF-2 when phosphorylated within the AD in MCF-7 cells were determined using ChIP-seq. The expression of ATF-2 and phosphorylated ATF-2 (pATF-2-Thr71) was determined in a series of 1,650 BC patients and correlated with clinico-pathological features and clinical outcome. Loss of ATF-2 diminished the growth-inhibitory effects of tamoxifen, while tamoxifen treatment induced ATF-2 phosphorylation within the AD, to regulate the expression of a set of 227 genes for proximal phospho-ATF-2 binding, involved in cell development, assembly and survival. Low expression of both ATF-2 and pATF-2-Thr71 was significantly associated with aggressive pathological features. Furthermore, pATF-2 was associated with both p-p38 and pJNK1/2 (< 0.0001). While expression of ATF-2 is not associated with outcome, pATF-2 is associated with longer disease-free (p = 0.002) and BC-specific survival in patients exposed to tamoxifen (p = 0.01). Furthermore, multivariate analysis confirmed pATF-2-Thr71 as an independent prognostic factor. ATF-2 is important for modulating the effect of tamoxifen and phosphorylation of ATF-2 within the AD at Thr71 predicts for improved outcome for ER-positive BC receiving tamoxifen.
Collapse
Affiliation(s)
- Bharath Rudraraju
- Department of Molecular and Clinical Cancer Medicine, Institute of Translational Medicine, University of Liverpool, The Duncan Building, Daulby Street, Liverpool, L69 3GA, UK
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
67
|
Aaptamines from the marine sponge Aaptos sp. display anticancer activities in human cancer cell lines and modulate AP-1-, NF-κB-, and p53-dependent transcriptional activity in mouse JB6 Cl41 cells. BIOMED RESEARCH INTERNATIONAL 2014; 2014:469309. [PMID: 25215281 PMCID: PMC4158141 DOI: 10.1155/2014/469309] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 06/02/2014] [Accepted: 07/11/2014] [Indexed: 12/19/2022]
Abstract
Aaptamine (8,9-dimethoxy-1H-benzo[de][1,6]naphthyridine) is a marine natural compound possessing antioxidative, antimicrobial, antifungal, and antiretroviral activity. Earlier, we have found that aaptamine and its derivatives demonstrate equal anticancer effects against the human germ cell cancer cell lines NT2 and NT2-R and cause some changes in the proteome of these cells. In order to explore further the mechanism of action of aaptamine and its derivatives, we studied the effects of aaptamine (1), demethyl(oxy)aaptamine (2), and isoaaptamine (3) on human cancer cell lines and on AP-1-, NF-κB-, and p53-dependent transcriptional activity in murine JB6 Cl41 cells. We showed that compounds 1–3 demonstrate anticancer activity in THP-1, HeLa, SNU-C4, SK-MEL-28, and MDA-MB-231 human cancer cell lines. Additionally, all compounds were found to prevent EGF-induced neoplastic transformation of murine JB6 Cl41 cells. Nuclear factors AP-1, NF-κB, and p53 are involved in the cellular response to high and nontoxic concentrations of aaptamine alkaloids 1–3. Furthermore, inhibition of EGF-induced JB6 cell transformation, which is exerted by the compounds 1–3 at low nontoxic concentrations of 0.7–2.1 μM, cannot be explained by activation of AP-1 and NF-κB.
Collapse
|
68
|
Fearnley GW, Odell AF, Latham AM, Mughal NA, Bruns AF, Burgoyne NJ, Homer-Vanniasinkam S, Zachary IC, Hollstein MC, Wheatcroft SB, Ponnambalam S. VEGF-A isoforms differentially regulate ATF-2-dependent VCAM-1 gene expression and endothelial-leukocyte interactions. Mol Biol Cell 2014; 25:2509-21. [PMID: 24966171 PMCID: PMC4142621 DOI: 10.1091/mbc.e14-05-0962] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
VEGF-A isoforms differentially stimulate endothelial VCAM-1 gene expression via an ERK1/2 protein kinase and ATF-2 transcription factor–dependent mechanism. Such signal transduction enables VEGF-A isoform–specific stimulation of leukocyte binding to endothelial cells, explaining how inflammation could be differentially regulated. Vascular endothelial growth factor A (VEGF-A) regulates many aspects of vascular physiology. VEGF-A stimulates signal transduction pathways that modulate endothelial outputs such as cell migration, proliferation, tubulogenesis, and cell–cell interactions. Multiple VEGF-A isoforms exist, but the biological significance of this is unclear. Here we analyzed VEGF-A isoform–specific stimulation of VCAM-1 gene expression, which controls endothelial–leukocyte interactions, and show that this is dependent on both ERK1/2 and activating transcription factor-2 (ATF-2). VEGF-A isoforms showed differential ERK1/2 and p38 MAPK phosphorylation kinetics. A key feature of VEGF-A isoform–specific ERK1/2 activation and nuclear translocation was increased phosphorylation of ATF-2 on threonine residue 71 (T71). Using reverse genetics, we showed ATF-2 to be functionally required for VEGF-A–stimulated endothelial VCAM-1 gene expression. ATF-2 knockdown blocked VEGF-A–stimulated VCAM-1 expression and endothelial–leukocyte interactions. ATF-2 was also required for other endothelial cell outputs, such as cell migration and tubulogenesis. In contrast, VCAM-1 was essential only for promoting endothelial–leukocyte interactions. This work presents a new paradigm for understanding how soluble growth factor isoforms program complex cellular outputs and responses by modulating signal transduction pathways.
Collapse
Affiliation(s)
- Gareth W Fearnley
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Adam F Odell
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Antony M Latham
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Nadeem A Mughal
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United KingdomLeeds Vascular Institute, Leeds General Infirmary, Leeds LS1 3EX, United Kingdom
| | - Alexander F Bruns
- Division of Cardiovascular and Diabetes Research, Faculty of Medicine and Health, LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | | | | | - Ian C Zachary
- Division of Cardiovascular Biology and Medicine, Rayne Institute, University College London, London, United Kingdom
| | | | - Stephen B Wheatcroft
- Division of Cardiovascular and Diabetes Research, Faculty of Medicine and Health, LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Sreenivasan Ponnambalam
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| |
Collapse
|
69
|
The regulatory role of activating transcription factor 2 in inflammation. Mediators Inflamm 2014; 2014:950472. [PMID: 25049453 PMCID: PMC4090481 DOI: 10.1155/2014/950472] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Accepted: 05/30/2014] [Indexed: 01/06/2023] Open
Abstract
Activating transcription factor 2 (ATF2) is a member of the leucine zipper family of DNA-binding proteins and is widely distributed in tissues including the liver, lung, spleen, and kidney. Like c-Jun and c-Fos, ATF2 responds to stress-related stimuli and may thereby influence cell proliferation, inflammation, apoptosis, oncogenesis, neurological development and function, and skeletal remodeling. Recent studies clarify the regulatory role of ATF2 in inflammation and describe potential inhibitors of this protein. In this paper, we summarize the properties and functions of ATF2 and explore potential applications of ATF2 inhibitors as tools for research and for the development of immunosuppressive and anti-inflammatory drugs.
Collapse
|
70
|
Jain K, Basu A. The Multifunctional Protein Kinase C-ε in Cancer Development and Progression. Cancers (Basel) 2014; 6:860-78. [PMID: 24727247 PMCID: PMC4074807 DOI: 10.3390/cancers6020860] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 03/27/2014] [Accepted: 04/01/2014] [Indexed: 12/31/2022] Open
Abstract
The protein kinase C (PKC) family proteins are important signal transducers and have long been the focus of cancer research. PKCɛ, a member of this family, is overexpressed in most solid tumors and plays critical roles in different processes that lead to cancer development. Studies using cell lines and animal models demonstrated the transforming potential of PKCɛ. While earlier research established the survival functions of PKCɛ, recent studies revealed its role in cell migration, invasion and cancer metastasis. PKCɛ has also been implicated in epithelial to mesenchymal transition (EMT), which may be the underlying mechanism by which it contributes to cell motility. In addition, PKCɛ affects cell-extracellular matrix (ECM) interactions by direct regulation of the cytoskeletal elements. Recent studies have also linked PKCɛ signaling to cancer stem cell functioning. This review focuses on the role of PKCɛ in different processes that lead to cancer development and progression. We also discussed current literatures on the pursuit of PKCɛ as a target for cancer therapy.
Collapse
Affiliation(s)
- Kirti Jain
- Department of Molecular and Medical Genetics, University of North Texas Health Science Center, Institute for Cancer Research, and Focused on Resources for her Health Education and Research, Fort Worth, TX 76107, USA.
| | - Alakananda Basu
- Department of Molecular and Medical Genetics, University of North Texas Health Science Center, Institute for Cancer Research, and Focused on Resources for her Health Education and Research, Fort Worth, TX 76107, USA.
| |
Collapse
|
71
|
Chen J, Solomides C, Simpkins H. Sensitization of mesothelioma cells to platinum-based chemotherapy by GSTπ knockdown. Biochem Biophys Res Commun 2014; 447:77-82. [PMID: 24690178 DOI: 10.1016/j.bbrc.2014.03.100] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 03/20/2014] [Indexed: 01/13/2023]
Abstract
It is predicted that the incidence of mesothelioma will increase and thus it is important to find new ways to treat this chemoresistant tumor. Glutathione-S-Transferase π (GSTπ) is found at significant levels in mesotheliomas and thus attenuating its intracellular levels may provide a means of sensitizing mesothelioma cells to chemotherapy. GSTπ knockdowns were therefore prepared with shRNA (less off-target effects) employing two cell lines (211H, H2452) that were typed by immunohistochemistry to be of mesothelial origin. The knockdowns exhibited a decrease in both total GST enzyme activity and GSTπ protein levels as well as an increase in both glutathione levels and sensitivity to cis and oxaliplatin. Cisplatin treatment of the knockdowns increased ROS levels significantly (as compared to the parental cells) and produced activation of the JNK/p38 pathways and activating transcription factor (ATF2). The degree of activation and increase in ROS appeared to correlate with the cell line's sensitivity to cisplatin. Treatment with N-Acetyl Cysteine decreased ROS production and JNK/p38 phosphorylation but had minimal affect on ATF2 suggesting a direct interaction of GTPπ with this transcription factor. Oxaliplatin treatment produced only minimal changes in ROS levels and activation of the JNK/p38 pathway. Recently, new methods of siRNA delivery (nanoparticles) have been shown to be effective in decreasing the levels of target proteins in humans including candidate genes involved in drug resistance - thus this approach may have promise in sensitizing cisplatin-resistant tumors to chemotherapy.
Collapse
Affiliation(s)
- Jianli Chen
- The Feinstein Institute for Medical Research, NS-LIJ Health System, 350 Community Drive, Manhasset, NY 11030, USA; Department of Pathology and Laboratory Medicine at Staten Island University Hospital, 475 Seaview Avenue, Staten Island, NY 10305, USA.
| | - Charalambos Solomides
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Jefferson Medical College, 132 S. 10th Street, 260E Main, Philadelphia, PA 19107, USA.
| | - Henry Simpkins
- The Feinstein Institute for Medical Research, NS-LIJ Health System, 350 Community Drive, Manhasset, NY 11030, USA; Department of Pathology and Laboratory Medicine at Staten Island University Hospital, 475 Seaview Avenue, Staten Island, NY 10305, USA.
| |
Collapse
|
72
|
Rao W, Li H, Song F, Zhang R, Yin Q, Wang Y, Xi Y, Ge H. OVA66 increases cell growth, invasion and survival via regulation of IGF-1R–MAPK signaling in human cancer cells. Carcinogenesis 2014; 35:1573-81. [DOI: 10.1093/carcin/bgu070] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
|
73
|
Valdez BC, Zander AR, Song G, Murray D, Nieto Y, Li Y, Champlin RE, Andersson BS. Synergistic cytotoxicity of gemcitabine, clofarabine and edelfosine in lymphoma cell lines. Blood Cancer J 2014; 4:e171. [PMID: 24413065 PMCID: PMC3913938 DOI: 10.1038/bcj.2013.69] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 11/11/2013] [Accepted: 11/22/2013] [Indexed: 01/04/2023] Open
Abstract
Treatments for lymphomas include gemcitabine (Gem) and clofarabine (Clo) which inhibit DNA synthesis. To improve their cytotoxicity, we studied their synergism with the alkyl phospholipid edelfosine (Ed). Exposure of the J45.01 and SUP-T1 (T-cell) and the OCI-LY10 (B-cell) lymphoma cell lines to IC10–IC20 levels of the drugs resulted in strong synergistic cytotoxicity for the 3-drug combination based on various assays of cell proliferation and apoptosis. Cell death correlated with increased phosphorylation of histone 2AX and KAP1, decreased mitochondrial transmembrane potential, increased production of reactive oxygen species and release of pro-apoptotic factors. Caspase 8-negative I9.2 cells were considerably more resistant to [Gem+Clo+Ed] than caspase 8-positive cells. In all three cell lines [Gem+Clo+Ed] decreased the level of phosphorylation of the pro-survival protein AKT and activated the stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) stress signaling pathway, which in J45.01 cells resulted in the phosphorylation and heterodimerization of the transcription factors ATF2 and c-Jun. The observed rational mechanism-based efficacy of [Gem+Clo+Ed] based on the synergistic convergence of several pro-death and anti-apoptotic signaling pathways in three very different cell backgrounds provides a powerful foundation for undertaking clinical trials of this drug combination for the treatment of lymphomas.
Collapse
Affiliation(s)
- B C Valdez
- Department of Stem Cell Transplantation and Cellular Therapy, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - A R Zander
- Department of Stem Cell Transplantation, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - G Song
- Department of Stem Cell Transplantation and Cellular Therapy, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - D Murray
- Department of Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada
| | - Y Nieto
- Department of Stem Cell Transplantation and Cellular Therapy, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Y Li
- Department of Stem Cell Transplantation and Cellular Therapy, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - R E Champlin
- Department of Stem Cell Transplantation and Cellular Therapy, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - B S Andersson
- Department of Stem Cell Transplantation and Cellular Therapy, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| |
Collapse
|
74
|
Molecular signatures of antibody responses derived from a systems biology study of five human vaccines. Nat Immunol 2013; 15:195-204. [PMID: 24336226 PMCID: PMC3946932 DOI: 10.1038/ni.2789] [Citation(s) in RCA: 526] [Impact Index Per Article: 47.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 11/14/2013] [Indexed: 12/18/2022]
Abstract
Many vaccines induce protective immunity via antibodies. Recent studies have used systems biological approaches to determine signatures that predict vaccine immunity in humans, but whether there is a ‘universal signature’ that can predict antibody responses to any vaccine, is unknown. Here we performed systems analyses of immune responses to the meningococcal polysaccharide and conjugate vaccines in healthy adults, in the broader context of our previous studies with the yellow fever and two influenza vaccines. To achieve this, we performed a large-scale network integration of public human blood transcriptomes, and systems-scale databases in specific biological contexts, and deduced a set of blood transcription modules. These modules revealed distinct transcriptional signatures of antibody responses to different classes of vaccines providing key insights into primary viral, protein recall and anti-polysaccharide responses. These results illuminate the early transcriptional programs orchestrating vaccine immunity in humans, and demonstrate the power of integrative network modeling.
Collapse
|
75
|
Feng FL, Yu Y, Liu C, Zhang BH, Cheng QB, Li B, Tan WF, Luo XJ, Jiang XQ. KAT5 silencing induces apoptosis of GBC-SD cells through p38MAPK-mediated upregulation of cleaved Casp9. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2013; 7:80-91. [PMID: 24427328 PMCID: PMC3885462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 12/05/2013] [Indexed: 06/03/2023]
Abstract
The poor overall prognosis of Gallbladder carcinoma (GBC) patients and the limited therapeutic regimens for these patients demonstrates the need for better therapeutic modalities, while the growing evidences have indicated that those genes contributed to epigenetic regulation may serve as therapeutic targets. The function of histone acetylation on growth and survival of GBC cells remains unknown. In present study, an RNAi screening of 16 genes involving histone acetyltransferases (HATs) was applied to GBC-SD cells and we found that KAT5 knockdown specifically inhibits the proliferation of GBC-SD cells by casp9-mediated apoptosis. Microarray data analysis showed that KAT5 RNAi may result in cleaved casp9 upregulation through p38MAPK activation in GBC-SD cells. The mRNA expression level of KAT5 was significantly upregulated in GBC tissues than in the adjacent normal tissues. In consistence with the mRNA level, the protein expression of KAT5 was markedly increased in tissues from patients with poor prognosis than those with good prognosis. These findings strongly indicated that KAT5 was implicated in GBC tumorigenesis and that its expression level was associated with the prognosis. Our work may also provide a potential therapeutic target for treatment of GBC patients.
Collapse
Affiliation(s)
- Fei-Ling Feng
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| | - Yong Yu
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| | - Chen Liu
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| | - Bai-He Zhang
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| | - Qing-Bao Cheng
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| | - Bin Li
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| | - Wei-Feng Tan
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| | - Xiang-Ji Luo
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| | - Xiao-Qing Jiang
- Department of Biliary I, Third Affiliated Hospital of PLA Second Military Medical University Shanghai, China
| |
Collapse
|
76
|
Endo M, Su L, Nielsen TO. Activating transcription factor 2 in mesenchymal tumors. Hum Pathol 2013; 45:276-84. [PMID: 24289970 DOI: 10.1016/j.humpath.2013.09.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 08/27/2013] [Accepted: 09/11/2013] [Indexed: 11/18/2022]
Abstract
Activating transcription factor 2 (ATF2) is a member of activator protein 1 superfamily, which can heterodimerize with other transcription factors regulating cell differentiation and survival. ATF2 assembles into a complex with the synovial sarcoma translocation, chromosome 18 (SS18)-synovial sarcoma, X breakpoint (SSX) fusion oncoprotein, and the transducin-like enhancer of split 1 (TLE1) corepressor, driving oncogenesis in synovial sarcoma. The fusion oncoproteins in many other translocation-associated sarcomas incorporate transcription factors from the ATF/cAMP response element binding or E26 families, which potentially form heterodimers with ATF2 to regulate transcription. ATF2 may therefore play an important role in the oncogenesis of many mesenchymal tumors, but as yet, little is known about its protein expression in patient specimens. Herein we perform immunohistochemical analyses using a validated specific antibody for ATF2 expression and intracellular localization on a cohort of 594 malignant and 207 benign mesenchymal tumors representing 47 diagnostic entities. Melanoma served as a positive control for nuclear and cytoplasmic staining. High nuclear ATF2 expression was mainly observed in translocation-associated and/or spindle cell sarcomas including synovial sarcoma, desmoplastic small round cell tumor, endometrial stromal sarcoma, gastrointestinal stromal tumor, malignant peripheral nerve sheath tumor, and solitary fibrous tumor. Cytoplasmic ATF2 expression was less frequently seen than nuclear expression in malignant mesenchymal tumors. Benign mesenchymal tumors mostly showed much lower nuclear and cytoplasmic ATF2 expression.
Collapse
Affiliation(s)
- Makoto Endo
- Genetic Pathology Evaluation Centre, University of British Columbia, Vancouver, British Columbia, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada; Department of Anatomic Pathology, Kyushu University, Fukuoka, Japan; Department of Orthopaedic Surgery, Kyushu University, Fukuoka, Japan
| | - Le Su
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Torsten O Nielsen
- Genetic Pathology Evaluation Centre, University of British Columbia, Vancouver, British Columbia, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
| |
Collapse
|
77
|
Rastogi R, Jiang Z, Ahmad N, Rosati R, Liu Y, Beuret L, Monks R, Charron J, Birnbaum MJ, Samavati L. Rapamycin induces mitogen-activated protein (MAP) kinase phosphatase-1 (MKP-1) expression through activation of protein kinase B and mitogen-activated protein kinase kinase pathways. J Biol Chem 2013; 288:33966-33977. [PMID: 24126911 DOI: 10.1074/jbc.m113.492702] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Mitogen-activated protein kinase phosphatase-1 (MKP-1), also known as dual specificity phosphatase-1 (DUSP-1), plays a crucial role in the deactivation of MAPKs. Several drugs with immune-suppressive properties modulate MKP-1 expression as part of their mechanism of action. We investigated the effect of mTOR inhibition through rapamycin and a dual mTOR inhibitor (AZD2014) on MKP-1 expression. Low dose rapamycin led to a rapid activation of both AKT and ERK pathways with a subsequent increase in MKP-1 expression. Rapamycin treatment led to phosphorylation of CREB, transcription factor 1 (ATF1), and ATF2, three transcription factors that bind to the cyclic AMP-responsive elements on the Mkp-1 promoter. Inhibition of either the MEK/ERK or the AKT pathway attenuated rapamycin-mediated MKP-1 induction. AZD2014 did not activate AKT but activated the ERK pathway, leading to a moderate MKP-1 induction. Using bone marrow-derived macrophages (BMDMs) derived from wild-type (WT) mice or mice deficient in AKT1 and AKT2 isoforms or BMDM from targeted deficiency in MEK1 and MEK2, we show that rapamycin treatment led to an increased MKP1 expression in BMDM from WT but failed to do so in BMDMs lacking the AKT1 isoform or MEK1 and MEK2. Importantly, rapamycin pretreatment inhibited LPS-mediated p38 activation and decreased nitric oxide and IL-6 production. Our work provides a conceptual framework for the observed immune modulatory effect of mTOR inhibition.
Collapse
Affiliation(s)
- Ruchi Rastogi
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Wayne State University School of Medicine and Detroit Medical Center, Detroit, Michigan 48201
| | - Zhongliang Jiang
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Wayne State University School of Medicine and Detroit Medical Center, Detroit, Michigan 48201
| | - Nisar Ahmad
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Wayne State University School of Medicine and Detroit Medical Center, Detroit, Michigan 48201
| | - Rita Rosati
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Wayne State University School of Medicine and Detroit Medical Center, Detroit, Michigan 48201
| | - Yusen Liu
- The Research Institute at Nationwide Children's Hospital, Columbus, Ohio 43205
| | - Laurent Beuret
- Centre de Recherche sur le Cancer de l'Université Laval, CRCHU-Q, L'Hôtel-Dieu de Québec, Québec G1R 2J6, Canada
| | - Robert Monks
- Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Jean Charron
- Centre de Recherche sur le Cancer de l'Université Laval, CRCHU-Q, L'Hôtel-Dieu de Québec, Québec G1R 2J6, Canada
| | - Morris J Birnbaum
- Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Lobelia Samavati
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Wayne State University School of Medicine and Detroit Medical Center, Detroit, Michigan 48201; Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan 48201.
| |
Collapse
|
78
|
Humphreys JM, Piala AT, Akella R, He H, Goldsmith EJ. Precisely ordered phosphorylation reactions in the p38 mitogen-activated protein (MAP) kinase cascade. J Biol Chem 2013; 288:23322-30. [PMID: 23744074 PMCID: PMC3743502 DOI: 10.1074/jbc.m113.462101] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 05/31/2013] [Indexed: 01/04/2023] Open
Abstract
The MAP kinase cascades, composed of a MAP3K, a MAP2K, and a MAPK, control switch responses to extracellular stimuli and stress in eukaryotes. The most important feature of these modules is thought to be the two double phosphorylation reactions catalyzed by MAP3Ks and MAP2Ks. We addressed whether the reactions are sequential or random in the p38 MAP kinase module. Mass spectrometry was used to track the phosphorylation of the MAP2K MEK6 by two MAP3Ks, TAO2 and ASK1, and the subsequent phosphorylation of p38α by MEK6/S*T* (where S (Ser) and T (Thr) are the two phosphorylation sites and * denotes phosphorylation). Both double phosphorylation reactions are precisely ordered. MEK6 is phosphorylated first on Thr-211 and then on Ser-207 by both MAP3Ks. This is the first demonstration of a precise reaction order for a MAP2K. p38α is phosphorylated first on Tyr-182 and then on Thr-180, the same reaction order observed previously in ERK2. Thus, intermediates were MEK6/ST* and p38α/TY*. Similarly, the phosphorylation of the p38α transcription factor substrate ATF2 occurs in a precise sequence. Progress curves for the appearance of intermediates were fit to kinetic models. The models confirmed the reaction order, revealed processivity in the phosphorylation of MEK6 by ASK1, and suggested that the order of phosphorylation is dictated by both binding and catalysis rates.
Collapse
Affiliation(s)
- John M. Humphreys
- From the Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Alexander T. Piala
- From the Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Radha Akella
- From the Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Haixia He
- From the Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Elizabeth J. Goldsmith
- From the Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| |
Collapse
|
79
|
Walluscheck D, Poehlmann A, Hartig R, Lendeckel U, Schönfeld P, Hotz-Wagenblatt A, Reissig K, Bajbouj K, Roessner A, Schneider-Stock R. ATF2 knockdown reinforces oxidative stress-induced apoptosis in TE7 cancer cells. J Cell Mol Med 2013; 17:976-88. [PMID: 23800081 PMCID: PMC3780530 DOI: 10.1111/jcmm.12071] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Accepted: 04/01/2013] [Indexed: 12/22/2022] Open
Abstract
Cancer cells showing low apoptotic effects following oxidative stress-induced DNA damage are mainly affected by growth arrest. Thus, recent studies focus on improving anti-cancer therapies by increasing apoptosis sensitivity. We aimed at identifying a universal molecule as potential target to enhance oxidative stress-based anti-cancer therapy through a switch from cell cycle arrest to apoptosis. A cDNA microarray was performed with hydrogen peroxide-treated oesophageal squamous epithelial cancer cells TE7. This cell line showed checkpoint activation via p21WAF1, but low apoptotic response following DNA damage. The potential target molecule was chosen depended on the following demands: it should regulate DNA damage response, cell cycle and apoptosis. As the transcription factor ATF2 is implicated in all these processes, we focused on this protein. We investigated checkpoint activation via ATF2. Indeed, ATF2 knockdown revealed ATF2-triggered p21WAF1 protein expression, suggesting p21WAF1 transactivation through ATF2. Using chromatin immunoprecipitation (ChIP), we identified a hitherto unknown ATF2-binding sequence in the p21WAF1 promoter. p-ATF2 was found to interact with p-c-Jun, creating the AP-1 complex. Moreover, ATF2 knockdown led to c-Jun downregulation. This suggests ATF2-driven induction of c-Jun expression, thereby enhancing ATF2 transcriptional activity via c-Jun-ATF2 heterodimerization. Notably, downregulation of ATF2 caused a switch from cell cycle arrest to reinforced apoptosis, presumably via p21WAF1 downregulation, confirming the importance of ATF2 in the establishment of cell cycle arrest. 1-Chloro-2,4-dinitrobenzene also led to ATF2-dependent G2/M arrest, suggesting that this is a general feature induced by oxidative stress. As ATF2 knockdown also increased apoptosis, we propose ATF2 as a target for combined oxidative stress-based anti-cancer therapies.
Collapse
Affiliation(s)
- Diana Walluscheck
- Department of Pathology, Otto-von-Guericke University, Magdeburg, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
80
|
Varsano T, Lau E, Feng Y, Garrido M, Milan L, Heynen-Genel S, Hassig CA, Ronai ZA. Inhibition of melanoma growth by small molecules that promote the mitochondrial localization of ATF2. Clin Cancer Res 2013; 19:2710-22. [PMID: 23589174 DOI: 10.1158/1078-0432.ccr-12-2689] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Effective therapy for malignant melanoma, the leading cause of death from skin cancer, remains an area of significant unmet need in oncology. The elevated expression of PKCε in advanced metastatic melanoma results in the increased phosphorylation of the transcription factor ATF2 on threonine 52, which causes its nuclear localization and confers its oncogenic activities. The nuclear-to-mitochondrial translocation of ATF2 following genotoxic stress promotes apoptosis, a function that is largely lost in melanoma cells, due to its confined nuclear localization. Therefore, promoting the nuclear export of ATF2, which sensitizes melanoma cells to apoptosis, represents a novel therapeutic modality. EXPERIMENTAL DESIGN We conducted a pilot high-throughput screen of 3,800 compounds to identify small molecules that promote melanoma cell death by inducing the cytoplasmic localization of ATF2. The imaging-based ATF2 translocation assay was conducted using UACC903 melanoma cells that stably express doxycycline-inducible GFP-ATF2. RESULTS We identified two compounds (SBI-0089410 and SBI-0087702) that promoted the cytoplasmic localization of ATF2, reduced cell viability, inhibited colony formation, cell motility, and anchorage-free growth, and increased mitochondrial membrane permeability. SBI-0089410 inhibited the 12-O-tetradecanoylphorbol-l3-acetate (TPA)-induced membrane translocation of protein kinase C (PKC) isoforms, whereas both compounds decreased ATF2 phosphorylation by PKCε and ATF2 transcriptional activity. Overexpression of either constitutively active PKCε or phosphomimic mutant ATF2(T52E) attenuated the cellular effects of the compounds. CONCLUSION The imaging-based high-throughput screen provides a proof-of-concept for the identification of small molecules that block the oncogenic addiction to PKCε signaling by promoting ATF2 nuclear export, resulting in mitochondrial membrane leakage and melanoma cell death.
Collapse
Affiliation(s)
- Tal Varsano
- Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA
| | | | | | | | | | | | | | | |
Collapse
|
81
|
Caporali A, Meloni M, Miller AM, Vierlinger K, Cardinali A, Spinetti G, Nailor A, Faglia E, Losa S, Gotti A, Fortunato O, Mitic T, Hofner M, Noehammer C, Madeddu P, Emanueli C. Soluble ST2 is regulated by p75 neurotrophin receptor and predicts mortality in diabetic patients with critical limb ischemia. Arterioscler Thromb Vasc Biol 2012; 32:e149-60. [PMID: 23065828 PMCID: PMC3616363 DOI: 10.1161/atvbaha.112.300497] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE The p75 neurotrophin receptor (p75(NTR)) contributes to diabetes mellitus-induced defective postischemic neovascularization. The interleukin-33 receptor ST2 is expressed as transmembrane (ST2L) and soluble (sST2) isoforms. Here, we studied the following: (1) the impact of p75(NTR) in the healing of ischemic and diabetic calf wounds; (2) the link between p75(NTR) and ST2; and (3) circulating sST2 levels in critical limb ischemia (CLI) patients. METHODS AND RESULTS Diabetes mellitus was induced in p75(NTR) knockout (p75KO) mice and wild-type (WT) littermates by streptozotocin. Diabetic and nondiabetic p75KO and WT mice received left limb ischemia induction and a full-thickness wound on the ipsilateral calf. Diabetes mellitus impaired wound closure and angiogenesis and increased ST2 expression in WT, but not in p75KO wounds. In cultured endothelial cells, p75(NTR) promoted ST2 (both isoforms) expression through p38(MAPK)/activating transcription factor 2 pathway activation. Next, sST2 was measured in the serum of patients with CLI undergoing either revascularization or limb amputation and in the 2 nondiabetic groups (with CLI or nonischemic individuals). Serum sST2 increased in diabetic patients with CLI and was directly associated with higher mortality at 1 year from revascularization. CONCLUSIONS p75(NTR) inhibits the healing of ischemic lower limb wounds in diabetes mellitus and promotes ST2 expression. Circulating sST2 predicts mortality in diabetic CLI patients.
Collapse
MESH Headings
- Activating Transcription Factor 2/metabolism
- Aged
- Aged, 80 and over
- Animals
- Biomarkers/metabolism
- Cells, Cultured
- Diabetes Complications/complications
- Diabetes Mellitus/metabolism
- Diabetes Mellitus/mortality
- Diabetes Mellitus/physiopathology
- Diabetes Mellitus, Experimental/chemically induced
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/physiopathology
- Disease Models, Animal
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Female
- Humans
- Interleukin-1 Receptor-Like 1 Protein
- Ischemia/etiology
- Ischemia/physiopathology
- Lower Extremity/blood supply
- Male
- Mice
- Mice, Knockout
- Middle Aged
- Nerve Tissue Proteins/pharmacology
- Nerve Tissue Proteins/physiology
- Predictive Value of Tests
- Receptors, Cell Surface/metabolism
- Receptors, Interleukin/metabolism
- Receptors, Nerve Growth Factor/deficiency
- Receptors, Nerve Growth Factor/genetics
- Receptors, Nerve Growth Factor/physiology
- Streptozocin/adverse effects
- Wound Healing/physiology
- p38 Mitogen-Activated Protein Kinases/metabolism
Collapse
Affiliation(s)
- Andrea Caporali
- Laboratories of Vascular Pathology and Regeneration, School of Clinical Sciences, University of Bristol, Bristol, England, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
82
|
Yang L, Huang P, Li F, Zhao L, Zhang Y, Li S, Gan Z, Lin A, Li W, Liu Y. c-Jun amino-terminal kinase-1 mediates glucose-responsive upregulation of the RNA editing enzyme ADAR2 in pancreatic beta-cells. PLoS One 2012; 7:e48611. [PMID: 23139803 PMCID: PMC3490865 DOI: 10.1371/journal.pone.0048611] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 09/27/2012] [Indexed: 11/18/2022] Open
Abstract
A-to-I RNA editing catalyzed by the two main members of the adenosine deaminase acting on RNA (ADAR) family, ADAR1 and ADAR2, represents a RNA-based recoding mechanism implicated in a variety of cellular processes. Previously we have demonstrated that the expression of ADAR2 in pancreatic islet β-cells is responsive to the metabolic cues and ADAR2 deficiency affects regulated cellular exocytosis. To investigate the molecular mechanism by which ADAR2 is metabolically regulated, we found that in cultured β-cells and primary islets, the stress-activated protein kinase JNK1 mediates the upregulation of ADAR2 in response to changes of the nutritional state. In parallel with glucose induction of ADAR2 expression, JNK phosphorylation was concurrently increased in insulin-secreting INS-1 β-cells. Pharmacological inhibition of JNKs or siRNA knockdown of the expression of JNK1 prominently suppressed glucose-augmented ADAR2 expression, resulting in decreased efficiency of ADAR2 auto-editing. Consistently, the mRNA expression of Adar2 was selectively reduced in the islets from JNK1 null mice in comparison with that of wild-type littermates or JNK2 null mice, and ablation of JNK1 diminished high-fat diet-induced Adar2 expression in the islets from JNK1 null mice. Furthermore, promoter analysis of the mouse Adar2 gene identified a glucose-responsive region and revealed the transcription factor c-Jun as a driver of Adar2 transcription. Taken together, these results demonstrate that JNK1 serves as a crucial component in mediating glucose-responsive upregulation of ADAR2 expression in pancreatic β-cells. Thus, the JNK1 pathway may be functionally linked to the nutrient-sensing actions of ADAR2-mediated RNA editing in professional secretory cells.
Collapse
Affiliation(s)
- Liu Yang
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Ping Huang
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Feng Li
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Liyun Zhao
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yongliang Zhang
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Shoufeng Li
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zhenji Gan
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Anning Lin
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Wenjun Li
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yong Liu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
- * E-mail:
| |
Collapse
|
83
|
Soengas MS. Mitophagy or how to control the Jekyll and Hyde embedded in mitochondrial metabolism: implications for melanoma progression and drug resistance. Pigment Cell Melanoma Res 2012; 25:721-31. [DOI: 10.1111/pcmr.12021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- María S. Soengas
- Melanoma Laboratory, Molecular Pathology Programme; Centro Nacional de Investigaciones Oncológicas (Spanish National Cancer Research Centre); Madrid; Spain
| |
Collapse
|