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Yamamoto H, Higa-Nakamine S, Noguchi N, Maeda N, Kondo Y, Toku S, Kukita I, Sugahara K. Desensitization by different strategies of epidermal growth factor receptor and ErbB4. J Pharmacol Sci 2014; 124:287-93. [PMID: 24553453 DOI: 10.1254/jphs.13r11cp] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Four transmembrane tyrosine kinases constitute the ErbB protein family: epidermal growth factor receptor (EGFR) or ErbB1, ErbB2, ErbB3, and ErbB4. In general, the structure and mechanism of the activation of these members are similar. However, significant differences in homologous desensitization are known between EGFR and ErbB4. Desensitization of ligand-occupied EGFR occurs by endocytosis, while that of ErbB4 occurs by selective cleavage at the cell surface. Because ErbB4 is abundantly expressed in neurons from fetal to adult brains, elucidation of the desensitization mechanism is important to understand neuronal development and synaptic functions. Recently, it has become clear that heterologous desensitization of EGFR and ErbB4 are induced by endocytosis and cleavage, respectively, similar to homologous desensitization. It has been reported that heterologous desensitization of EGFR is induced by serine phosphorylation of EGFR via the p38 mitogen-activated protein kinase (p38 MAP kinase) pathway in various cell lines, including alveolar epithelial cells. In contrast, the protein kinase C pathway is involved in ErbB4 cleavage. In this review, we will describe recent advances in the desensitization mechanisms of EGFR and ErbB4, mainly in alveolar epithelial cells and hypothalamic neurons, respectively.
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Affiliation(s)
- Hideyuki Yamamoto
- Department of Biochemistry, Graduate School of Medicine, University of the Ryukyus, Japan
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152
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Avivar-Valderas A, Wen HC, Aguirre-Ghiso JA. Stress signaling and the shaping of the mammary tissue in development and cancer. Oncogene 2014; 33:5483-90. [PMID: 24413078 DOI: 10.1038/onc.2013.554] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 11/18/2013] [Accepted: 11/18/2013] [Indexed: 12/11/2022]
Abstract
The postnatal mammary gland develops extensively through cycles of proliferation, branching, involution and remodeling. We review recent advances made in the field of stress signaling pathways and its roles in mammary gland organogenesis, how they contribute to normal organ specification and homeostasis and how its subversion by oncogenes leads to cancer. We analyze stress signaling in mammary gland biology taking into account the interrelationship with the extracellular matrix and adhesion signaling during morphogenesis. By integrating the information gathered from in vivo and three dimensional in vitro organogenesis studies, we review the novel contribution of p38(SAPK), c-Jun NH2-terminal kinase and PKR-like endoplasmic reticulum kinase (PERK) signaling pathways to the timely activation of cell death, correct establishment of polarity and growth arrest and autophagy, respectively. We also review the evidence supporting that the activation of the aforementioned stress kinases maintain breast acinar structures as part of a tumor suppressive program and that its deregulation is commonplace during breast cancer initiation.
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Affiliation(s)
- A Avivar-Valderas
- 1] Division of Hematology and Oncology, Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA [2] Department of Otolaryngology, Mount Sinai School of Medicine, New York, NY, USA [3] Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY, USA
| | - H C Wen
- 1] Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY, USA [2] Department of Oncological Sciences, Mount Sinai School of Medicine, New York, NY, USA
| | - J A Aguirre-Ghiso
- 1] Division of Hematology and Oncology, Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA [2] Department of Otolaryngology, Mount Sinai School of Medicine, New York, NY, USA [3] Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY, USA [4] Black Family Stem Cell Institute, Mount Sinai School of Medicine, New York, NY, USA
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153
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Greggio E, Singleton A. Kinase signaling pathways as potential targets in the treatment of Parkinson’s disease. Expert Rev Proteomics 2014; 4:783-92. [DOI: 10.1586/14789450.4.6.783] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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154
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Lai TW, Zhang S, Wang YT. Excitotoxicity and stroke: identifying novel targets for neuroprotection. Prog Neurobiol 2013; 115:157-88. [PMID: 24361499 DOI: 10.1016/j.pneurobio.2013.11.006] [Citation(s) in RCA: 772] [Impact Index Per Article: 70.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 11/28/2013] [Accepted: 11/29/2013] [Indexed: 01/22/2023]
Abstract
Excitotoxicity, the specific type of neurotoxicity mediated by glutamate, may be the missing link between ischemia and neuronal death, and intervening the mechanistic steps that lead to excitotoxicity can prevent stroke damage. Interest in excitotoxicity began fifty years ago when monosodium glutamate was found to be neurotoxic. Evidence soon demonstrated that glutamate is not only the primary excitatory neurotransmitter in the adult brain, but also a critical transmitter for signaling neurons to degenerate following stroke. The finding led to a number of clinical trials that tested inhibitors of excitotoxicity in stroke patients. Glutamate exerts its function in large by activating the calcium-permeable ionotropic NMDA receptor (NMDAR), and different subpopulations of the NMDAR may generate different functional outputs, depending on the signaling proteins directly bound or indirectly coupled to its large cytoplasmic tail. Synaptic activity activates the GluN2A subunit-containing NMDAR, leading to activation of the pro-survival signaling proteins Akt, ERK, and CREB. During a brief episode of ischemia, the extracellular glutamate concentration rises abruptly, and stimulation of the GluN2B-containing NMDAR in the extrasynaptic sites triggers excitotoxic neuronal death via PTEN, cdk5, and DAPK1, which are directly bound to the NMDAR, nNOS, which is indirectly coupled to the NMDAR via PSD95, and calpain, p25, STEP, p38, JNK, and SREBP1, which are further downstream. This review aims to provide a comprehensive summary of the literature on excitotoxicity and our perspectives on how the new generation of excitotoxicity inhibitors may succeed despite the failure of the previous generation of drugs.
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Affiliation(s)
- Ted Weita Lai
- Graduate Institute of Clinical Medical Science, China Medical University, 91 Hsueh-Shih Road, 40402 Taichung, Taiwan; Translational Medicine Research Center, China Medical University Hospital, 2 Yu-De Road, 40447 Taichung, Taiwan.
| | - Shu Zhang
- Translational Medicine Research Center, China Medical University Hospital, 2 Yu-De Road, 40447 Taichung, Taiwan; Brain Research Center, University of British Columbia, 2211 Wesbrook Mall, V6T 2B5 Vancouver, Canada
| | - Yu Tian Wang
- Brain Research Center, University of British Columbia, 2211 Wesbrook Mall, V6T 2B5 Vancouver, Canada.
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155
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Ozcan L, Cristina de Souza J, Harari AA, Backs J, Olson EN, Tabas I. Activation of calcium/calmodulin-dependent protein kinase II in obesity mediates suppression of hepatic insulin signaling. Cell Metab 2013; 18:803-15. [PMID: 24268736 PMCID: PMC3863383 DOI: 10.1016/j.cmet.2013.10.011] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 09/07/2013] [Accepted: 10/11/2013] [Indexed: 01/12/2023]
Abstract
A hallmark of obesity is selective suppression of hepatic insulin signaling ("insulin resistance"), but critical gaps remain in our understanding of the molecular mechanisms. We now report a major role for hepatic CaMKII, a calcium-responsive kinase that is activated in obesity. Genetic targeting of hepatic CaMKII, its downstream mediator p38, or the p38 substrate and stabilizer MK2 enhances insulin-induced p-Akt in palmitate-treated hepatocytes and obese mouse liver, leading to metabolic improvement. The mechanism of improvement begins with induction of ATF6 and the ATF6 target p58(IPK), a chaperone that suppresses the PERK-p-eIF2α-ATF4 branch of the UPR. The result is a decrease in the ATF4 target TRB3, an inhibitor of insulin-induced p-Akt, leading to enhanced activation of Akt and its downstream metabolic mediators. These findings increase our understanding of the molecular mechanisms linking obesity to selective insulin resistance and suggest new therapeutic targets for type 2 diabetes and metabolic syndrome.
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Affiliation(s)
- Lale Ozcan
- Department of Medicine, Columbia University, New York, NY 10032, USA.
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156
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George MD, Wine RN, Lackford B, Kissling GE, Akiyama SK, Olden K, Roberts JD. p38 mitogen-activated protein kinase interacts with vinculin at focal adhesions during fatty acid-stimulated cell adhesion. Biochem Cell Biol 2013; 91:404-18. [PMID: 24219282 PMCID: PMC3935246 DOI: 10.1139/bcb-2013-0013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Arachidonic acid stimulates cell adhesion by activating α2β1 integrins in a process that depends on protein kinases, including p38 mitogen activated protein kinase. Here, we describe the interaction of cytoskeletal components with key signaling molecules that contribute to the spreading of, and morphological changes in, arachidonic acid-treated MDA-MB-435 human breast carcinoma cells. Arachidonic acid-treated cells showed increased attachment and spreading on collagen type IV, as measured by electric cell-substrate impedance sensing. Fatty acid-treated cells displayed short cortical actin filaments associated with an increased number of β1 integrin-containing pseudopodia, whereas untreated cells displayed elongated stress fibers and fewer clusters of β1 integrins. Confocal microscopy of arachidonic acid-treated cells showed that vinculin and phospho-p38 both appeared enriched in pseudopodia and at the tips of actin filaments, and fluorescence ratio imaging indicated the increase was specific for the phospho-(active) form of p38. Immunoprecipitates of phospho-p38 from extracts of arachidonic acid-treated cells contained vinculin, and GST-vinculin fusion proteins carrying the central region of vinculin bound phospho-p38, whereas fusion proteins expressing the terminal portions of vinculin did not. These data suggest that phospho-p38 associates with particular domains on critical focal adhesion proteins that are involved in tumor cell adhesion and spreading, and that this association can be regulated by factors in the tumor microenvironment.
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Affiliation(s)
- Margaret D George
- National Institute of Environmental Health Sciences, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
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157
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Choi H, Park JY, Kim HJ, Noh M, Ueyama T, Bae Y, Lee TR, Shin DW. Hydrogen peroxide generated by DUOX1 regulates the expression levels of specific differentiation markers in normal human keratinocytes. J Dermatol Sci 2013; 74:56-63. [PMID: 24332816 DOI: 10.1016/j.jdermsci.2013.11.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 11/07/2013] [Accepted: 11/19/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Recent studies have demonstrated that the production of reactive oxygen species (ROS) itself plays an indispensable role in the process of differentiation in various tissues. However, it is unclear whether ROS have an effect on the differentiation of keratinocytes essential for the development of the epidermal permeability barrier. OBJECTIVE The aim of the study is to determine a major H2O2-generating source by ionomycin in normal human keratinocytes (NHKs), and elucidate the physiological role of H2O2 generated by identified dual oxidase 1 (DUOX1) on differentiation markers of NHKs. METHODS To detect H2O2 level generated by ionomycin in NHKs, luminal-HRP assays are performed. To examine the effects of DUOX1 on differentiation markers of NHKs, analysis of Q-RT-PCR, siRNA knockdown, and Western blot analysis were performed. RESULTS We found that levels of H2O2 generated by ionomycin, a Ca(2+) signal inducer, showed Ca(2+) dependence manner. In addition, DPI, an inhibitor of NOXes, significantly reversed the ionomycin-induced H2O2 level, and inhibited the mRNA expression levels of keratin 1, keratin 10, and filaggrin compared with other ROS generating system inhibitors. Interestingly, we demonstrated that extracellular Ca(2+) markedly up-regulated mRNA expression levels of DUOX1 among NADPH oxidase (NOX) isoforms. Knockdown of DUOX1 by RNA interference (RNAi) in NHKs significantly antagonized an increase of ionomycin-induced H2O2 level, and specifically decreased the expressions of several keratinocyte differentiation markers such as keratin 1, transglutaminase 3, desmoglein 1, and aquaporin 9. In addition, we also found that formation of cornified envelope was significantly reduced in DUOX1-knockdown NHKs. CONCLUSION These results suggest that DUOX1 is the major H2O2-producing source in NHKs stimulated with Ca(2+), and plays a significant role in regulating the expression of specific markers necessary for the normal differentiation of keratinocytes.
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Affiliation(s)
- Hyun Choi
- Bioscience Research Institute, Amorepacific Corporation R&D Center, Yongin-si, Gyeonggi-do 446-729, Republic of Korea
| | - Ju-Yearl Park
- Bioscience Research Institute, Amorepacific Corporation R&D Center, Yongin-si, Gyeonggi-do 446-729, Republic of Korea
| | - Hyoung-June Kim
- Bioscience Research Institute, Amorepacific Corporation R&D Center, Yongin-si, Gyeonggi-do 446-729, Republic of Korea
| | - Minsoo Noh
- College of Pharmacy, Seoul University, Seoul 151-742, Republic of Korea
| | - Takehiko Ueyama
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Republic of Korea
| | - Yunsoo Bae
- Department of Life Sciences, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Tae Ryong Lee
- Bioscience Research Institute, Amorepacific Corporation R&D Center, Yongin-si, Gyeonggi-do 446-729, Republic of Korea.
| | - Dong Wook Shin
- Bioscience Research Institute, Amorepacific Corporation R&D Center, Yongin-si, Gyeonggi-do 446-729, Republic of Korea.
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158
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159
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Plumbagin induces apoptotic and autophagic cell death through inhibition of the PI3K/Akt/mTOR pathway in human non-small cell lung cancer cells. Cancer Lett 2013; 344:239-59. [PMID: 24280585 DOI: 10.1016/j.canlet.2013.11.001] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 10/30/2013] [Accepted: 11/07/2013] [Indexed: 12/22/2022]
Abstract
Plumbagin (PLB) has shown anti-cancer activity but the mechanism is unclear. This study has found that PLB has a potent pro-apoptotic and pro-autophagic effect on A549 and H23 cells. PLB arrests cells in G2/M phase, and increases the intracellular level of reactive oxygen species in both cell lines. PLB dose-dependently induces autophagy through inhibition of PI3K/Akt/mTOR pathway as indicated by reduced phosphorylation of Akt and mTOR. Inhibition or induction of autophagy enhances PLB-induced apoptosis. There is crosstalk between PLB-induced apoptosis and autophagy. These findings indicate that PLB initiates both apoptosis and autophagy in NSCLC cells through coordinated pathways.
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160
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Pereira RC, Scaranari M, Benelli R, Strada P, Reis RL, Cancedda R, Gentili C. Dual effect of platelet lysate on human articular cartilage: a maintenance of chondrogenic potential and a transient proinflammatory activity followed by an inflammation resolution. Tissue Eng Part A 2013; 19:1476-88. [PMID: 23360471 DOI: 10.1089/ten.tea.2012.0225] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Platelet-rich plasma (PRP), a cocktail of platelet growth factors and bioactive proteins, has been proposed as a therapeutic agent to restore damaged articular cartilage. We report the biological effect of the platelet lysate (PL), a PRP derivative, on primary human articular chondrocytes cultured under both physiological and inflammatory conditions. When added to the culture medium, PL induced a strong mitogenic response in the chondrocytes. The in vitro expanded cell population maintained a chondrogenic redifferentiation potential as revealed by micromass culture in vitro and ectopic cartilage formation in vivo. Further, in chondrocytes cultured in the presence of the proinflammatory cytokine interleukin-1α (IL-1α), the PL induced a drastic enhancement of the synthesis of the cytokines IL-6 and IL-8 and of neutrophil-gelatinase associated lipocalin, a lipocalin expressed during chondrocyte differentiation and inflammation. These events were mediated by the p38 MAP kinase and NF-κB pathways. We observed that inflammatory stimuli activated phospo-MAP kinase-activated protein kinase 2, a direct target of p38. The proinflammatory effect of the PL was a transient phenomenon; after an initial upregulation, we observed significant reduction of the NF-κB activity together with the repression of the inflammatory enzyme cyclooxygenase-2. Moreover, the medium of chondrocytes cultured in the simultaneous presence of PL and IL-1α, showed a significant enhancement of the chemoattractant activity versus untreated chondrocytes. Our findings support the concept that the platelet products have a direct beneficial effect on articular chondrocytes and could drive in sequence a transient activation and the resolution of the inflammatory process, thus providing a rational for their use as therapeutic agents in cartilage inflammation and damage.
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Affiliation(s)
- Rui Cruz Pereira
- Dipartimento di Medicina Sperimentale, Universita' di Genova, Genova, Italy
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161
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Qin B, Panickar KS, Anderson RA. Cinnamon polyphenols regulate S100β, sirtuins, and neuroactive proteins in rat C6 glioma cells. Nutrition 2013; 30:210-7. [PMID: 24239092 DOI: 10.1016/j.nut.2013.07.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 06/26/2013] [Accepted: 07/02/2013] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Increasing evidence suggests that cinnamon has many health benefits when used in herbal medicine and as a dietary ingredient. The aim of this study was to investigate the effects of an aqueous extract of cinnamon, high in type A polyphenols, on molecular targets in rat C6 glioma cells that underlie their protective effects. METHODS C6 rat glioma cells were seeded in 35-mm culture dishes or six-well plates, then were incubated with cinnamon polyphenols at doses of 10 and 20 μg/mL for 24 h. The targeting protein expression, secretion, and phosphorylation were evaluated by immunoprecitation/immunoblotting and immunofluorescence imaging. RESULTS Cinnamon polyphenols significantly enhanced secretion of S100β, a Ca(2+)-binding protein, and increased intracellular S100β expression after 24 h of incubation, in rat C6 glioma cells. Cinnamon polyphenols also enhanced protein levels of sirtuin 1, 2, and 3, deacetylases important in cell survival, and the tumor suppressor protein, p53, and inhibited the inflammatory factors, tumor necrosis factor alpha, and phospho-p65, a subunit of nuclear factor-κβ. Cinnamon polyphenols also up-regulated levels of phospho-p38, extracellular signal-regulated protein and mitogen-activated protein and kinase-activated protein kinases that may be important for prosurvival functions. CONCLUSION Our results indicate that the effects of cinnamon polyphenols on upregulating prosurvival proteins, activating mitogen-activated protein kinase pathways, and decreasing proinflammatory cytokines may contribute to their neuroprotective effects.
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Affiliation(s)
- Bolin Qin
- Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD, USA; Integrity Nutraceuticals International, Spring Hill, TN, USA.
| | - Kiran S Panickar
- Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD, USA; Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Richard A Anderson
- Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD, USA
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162
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Aoshiba K, Tsuji T, Kameyama S, Itoh M, Semba S, Yamaguchi K, Nakamura H. Senescence-associated secretory phenotype in a mouse model of bleomycin-induced lung injury. EXPERIMENTAL AND TOXICOLOGIC PATHOLOGY : OFFICIAL JOURNAL OF THE GESELLSCHAFT FUR TOXIKOLOGISCHE PATHOLOGIE 2013; 65:1053-62. [PMID: 23688655 DOI: 10.1016/j.etp.2013.04.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 04/01/2013] [Accepted: 04/09/2013] [Indexed: 02/07/2023]
Abstract
Bleomycin produces DNA damage, apoptosis and senescence, all of which play crucial roles in the development of pulmonary fibrosis. Recently, close attention has been paid to a DNA damage-induced phenotypic change (senescence-associated secretory phenotype; SASP) as a trigger for the secretion of various mediators which modify the processes of tissue injury, inflammation, repair and fibrosis. We characterized the SASP in a murine model of bleomycin-induced lung injury. Mice were intratracheally administered bleomycin or control saline, and the lungs were obtained on days 7, 14 and 21. The occurrence of DNA damage and the SASP in the lungs was examined by immunostaining. γH2AX immunostaining of the bleomycin-treated lungs revealed double-strand breaks (DSBs), largely within E-cadherin-positive, β4-integirn-positive alveolar epithelial cells. The DSBs were associated with phosphorylation of ATM/ATR, a central signal transducer mediating the DNA damage response, and upregulation of the cyclin-dependent kinase inhibitor p21(CIP1). The DSBs persisted for at least 21 days after the bleomycin exposure, although it began to wane after 7 days. A subpopulation of the γH2AX-positive, DNA-damaged cells exhibited the SASP, characterized by overexpression of IL-6, TNFα, MMP-2 and MMP-9, in association with the phosphorylation of IKKα/β and p38 MAPK. Persistent DNA damage and the SASP are induced in the process of bleomycin-induced lung injury and repair, suggesting that these events play an important role in the regulation of inflammation and tissue remodeling in bleomycin-induced pneumopathy.
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Affiliation(s)
- Kazutetsu Aoshiba
- Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, Japan.
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163
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Mellier G, Liu D, Bellot G, Holme AL, Pervaiz S. Small molecule sensitization to TRAIL is mediated via nuclear localization, phosphorylation and inhibition of chaperone activity of Hsp27. Cell Death Dis 2013; 4:e890. [PMID: 24176848 PMCID: PMC3920951 DOI: 10.1038/cddis.2013.413] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 09/19/2013] [Accepted: 09/20/2013] [Indexed: 02/05/2023]
Abstract
The small chaperone protein Hsp27 confers resistance to apoptosis, and therefore is an attractive anticancer drug target. We report here a novel mechanism underlying the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) sensitizing activity of the small molecule LY303511, an inactive analog of the phosphoinositide 3-kinase inhibitor inhibitor LY294002, in HeLa cells that are refractory to TRAIL-induced apoptosis. On the basis of the fact that LY303511 is derived from LY294002, itself derived from quercetin, and earlier findings indicating that quercetin and LY294002 affected Hsp27 expression, we investigated whether LY303511 sensitized cancer cells to TRAIL via a conserved inhibitory effect on Hsp27. We provide evidence that upon treatment with LY303511, Hsp27 is progressively sequestered in the nucleus, thus reducing its protective effect in the cytosol during the apoptotic process. LY303511-induced nuclear translocation of Hsp27 is linked to its sustained phosphorylation via activation of p38 kinase and MAPKAP kinase 2 and the inhibition of PP2A. Furthermore, Hsp27 phosphorylation leads to the subsequent dissociation of its large oligomers and a decrease in its chaperone activity, thereby further compromising the death inhibitory activity of Hsp27. Furthermore, genetic manipulation of Hsp27 expression significantly affected the TRAIL sensitizing activity of LY303511, which corroborated the Hsp27 targeting activity of LY303511. Taken together, these data indicate a novel mechanism of small molecule sensitization to TRAIL through targeting of Hsp27 functions, rather than its overall expression, leading to decreased cellular protection, which could have therapeutic implications for overcoming chemotherapy resistance in tumor cells.
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Affiliation(s)
- G Mellier
- 1] ROS, Apoptosis and Cancer Biology Laboratory, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore [2] Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore, Singapore
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164
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Crowe J, Aubareda A, McNamee K, Przybycien PM, Lu X, Williams RO, Bou-Gharios G, Saklatvala J, Dean JLE. Heat shock protein B1-deficient mice display impaired wound healing. PLoS One 2013; 8:e77383. [PMID: 24143227 PMCID: PMC3797036 DOI: 10.1371/journal.pone.0077383] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 09/05/2013] [Indexed: 01/27/2023] Open
Abstract
There is large literature describing in vitro experiments on heat shock protein (hsp)B1 but understanding of its function in vivo is limited to studies in mice overexpressing human hspB1 protein. Experiments in cells have shown that hspB1 has chaperone activity, a cytoprotective role, regulates inflammatory gene expression, and drives cell proliferation. To investigate the function of the protein in vivo we generated hspB1-deficient mice. HspB1-deficient fibroblasts display increased expression of the pro-inflammatory cytokine, interleukin-6, compared to wild-type cells, but reduced proliferation. HspB1-deficient fibroblasts exhibit reduced entry into S phase and increased expression of cyclin-dependent kinase inhibitors p27(kip1) and p21(waf1). The expression of hspB1 protein and mRNA is also controlled by the cell cycle. To investigate the physiological function of hspB1 in regulating inflammation and cell proliferation we used an excisional cutaneous wound healing model. There was a significant impairment in the rate of healing of wounds in hspB1-deficient mice, characterised by reduced re-epithelialisation and collagen deposition but also increased inflammation. HspB1 deficiency augments neutrophil infiltration in wounds, driven by increased chemokine (C-X-C motif) ligand 1 expression. This appears to be a general mechanism as similar results were obtained in the air-pouch and peritonitis models of acute inflammation.
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Affiliation(s)
- Jonathan Crowe
- Department of Medicine, Imperial College London, London, United Kingdom
| | - Anna Aubareda
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Kay McNamee
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Paulina M. Przybycien
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Xin Lu
- The Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Richard O. Williams
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - George Bou-Gharios
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Jeremy Saklatvala
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Jonathan L. E. Dean
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
- * E-mail:
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Yang CR, Liao WS, Wu YH, Murugan K, Chen C, Chao JI. CR108, a novel vitamin K3 derivative induces apoptosis and breast tumor inhibition by reactive oxygen species and mitochondrial dysfunction. Toxicol Appl Pharmacol 2013; 273:611-22. [PMID: 24128853 DOI: 10.1016/j.taap.2013.10.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 09/27/2013] [Accepted: 10/05/2013] [Indexed: 11/26/2022]
Abstract
Vitamin K3 derivatives have been shown to exert anticancer activities. Here we show a novel vitamin K3 derivative (S)-2-(2-hydroxy-3-methylbutylthio)naphthalene-1,4-dione, which is named as CR108 that induces apoptosis and tumor inhibition through reactive oxygen species (ROS) and mitochondrial dysfunction in human breast cancer. CR108 is more effective on the breast cancer cell death than other vitamin K3 derivatives. Moreover, CR108 induced apoptosis in both the non-HER-2-overexpressed MCF-7 and HER-2-overexpressed BT-474 breast cancer cells. CR108 caused the loss of mitochondrial membrane potential, cytochrome c released from mitochondria to cytosol, and cleaved PARP proteins for apoptosis induction. CR108 markedly increased ROS levels in breast cancer cells. N-acetylcysteine (NAC), a general ROS scavenger, completely blocked the CR108-induced ROS levels, mitochondrial dysfunction and apoptosis. Interestingly, CR108 increased the phosphorylation of p38 MAP kinase but conversely inhibited the survivin protein expression. NAC treatment prevented the activation of p38 MAP kinase and rescued the survivin protein levels. SB202190, a specific p38 MAP kinase inhibitor, recovered the survivin protein levels and attenuated the cytotoxicity of CR108-treated cells. Furthermore, CR108 inhibited the xenografted human breast tumor growth in nude mice. Together, we demonstrate that CR108 is a novel vitamin K3 derivative that induces apoptosis and tumor inhibition by ROS production and mitochondrial dysfunction and associates with the phosphorylation of p38 MAP kinase and the inhibition of survivin in the human breast cancer.
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Affiliation(s)
- Chun-Ru Yang
- Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 30068, Taiwan
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166
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Murata S, Shiragami R, Kosugi C, Tezuka T, Yamazaki M, Hirano A, Yoshimura Y, Suzuki M, Shuto K, Ohkohchi N, Koda K. Antitumor effect of 1, 8-cineole against colon cancer. Oncol Rep 2013; 30:2647-52. [PMID: 24085263 DOI: 10.3892/or.2013.2763] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 08/01/2013] [Indexed: 12/18/2022] Open
Abstract
Several essential oils possess pharmacological effects. Among the various constituents of essential oils, 1, 8-cineole has been shown to possess pharmacological effects such as anti-bacterial and anti-inflammatory effects. The effect of 1, 8-cineole on human colorectal cancer cells, however, has not reported previously. In this study, we have investigated the anti-proliferative effect of 1, 8-cineole on human colon cancer cell lines HCT116 and RKO by WST-8 and BrdU assays. The cytotoxicity of 1, 8-cineole was investigated by LDH activity and TUNEL staining. The mechanism of apoptosis by 1, 8-cineole was determined by western blot analyses. In in vivo study, RKO cells were injected into the SCID mice and the effect of 1, 8-cineole was investigated. Specific induction of apoptosis, not necrosis, was observed in human colon cancer cell lines HCT116 and RKO by 1, 8-cineole. The treatment with 1, 8-cineole was associated with inactivation of survivin and Akt and activation of p38. These molecules induced cleaved PARP and caspase-3, finally causing apoptosis. In xenotransplanted SCID mice, the 1, 8-cineole group showed significantly inhibited tumor progression compared to the control group. These results indicated 1, 8-cineole suppressed human colorectal cancer proliferation by inducing apoptosis. Based on these studies 1, 8-cineole would be an effective strategy to treat colorectal cancer.
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Affiliation(s)
- Soichiro Murata
- Department of Surgery, Teikyo University Chiba Medical Center, Ichihara, Japan
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167
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Byun K, Kim TK, Oh J, Bayarsaikhan E, Kim D, Lee MY, Pack CG, Hwang D, Lee B. Heat shock instructs hESCs to exit from the self-renewal program through negative regulation of OCT4 by SAPK/JNK and HSF1 pathway. Stem Cell Res 2013; 11:1323-34. [PMID: 24090933 DOI: 10.1016/j.scr.2013.08.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Revised: 08/29/2013] [Accepted: 08/30/2013] [Indexed: 10/26/2022] Open
Abstract
Environmental factors affect self-renewal of stem cells by modulating the components of self-renewal networks. Heat shock, an environmental factor, induces heat shock factors (HSFs), which up-regulate stress response-related genes. However, the link of heat shock to self-renewal of stem cells has not been elucidated yet. Here, we present the direct link of heat shock to a core stem cell regulator, OCT4, in the self-renewal network through SAPK/JNK and HSF1 pathway. We first showed that heat shock initiated differentiation of human embryonic stem cells (hESCs). Gene expression analysis revealed that heat shock increased the expression of many genes involved in cellular processes related to differentiation of stem cells. We then examined the effects of HSFs induced by heat shock on core self-renewal factors. Among HSFs, heat shock induced mainly HSF1 in hESCs. The HSF1 repressed the expression of OCT4, leading to the differentiation of hESCs and the above differentiation-related gene expression change. We further examined the effects of the upstream MAP (mitogen-activated protein) kinases of HSF1 on the repression of OCT4 expression by HSF1. Among the MAP kinases, SAPK/JNK controlled predominantly the repression of the OCT4 expression by HSF1. The direct link of heat shock to the core self-renewal regulator through SAPK/JNK and HSF1 provides a fundamental basis for understanding the effect of heat and other stresses involving activation of HSF1 on the self-renewal program and further controlling differentiation of hESCs in a broad spectrum of stem cell applications using these stresses.
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Affiliation(s)
- Kyunghee Byun
- Center for Genomics and Proteomics & Stem Cell Core Facility, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 406-840, Republic of Korea; Department of Anatomy and Cell Biology, Gachon University Medical School, Incheon 406-840, Republic of Korea
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168
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Simon S, Dimitrova V, Gibert B, Virot S, Mounier N, Nivon M, Kretz-Remy C, Corset V, Mehlen P, Arrigo AP. Analysis of the dominant effects mediated by wild type or R120G mutant of αB-crystallin (HspB5) towards Hsp27 (HspB1). PLoS One 2013; 8:e70545. [PMID: 23950959 PMCID: PMC3741289 DOI: 10.1371/journal.pone.0070545] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 06/19/2013] [Indexed: 12/21/2022] Open
Abstract
Several human small heat shock proteins (sHsps) are phosphorylated oligomeric chaperones that enhance stress resistance. They are characterized by their ability to interact and form polydispersed hetero-oligomeric complexes. We have analyzed the cellular consequences of the stable expression of either wild type HspB5 or its cataracts and myopathies inducing R120G mutant in growing and oxidative stress treated HeLa cells that originally express only HspB1. Here, we describe that wild type and mutant HspB5 induce drastic and opposite effects on cell morphology and oxidative stress resistance. The cellular distribution and phosphorylation of these polypeptides as well as the oligomerization profile of the resulting hetero-oligomeric complexes formed by HspB1 with the two types of exogenous polypeptides revealed the dominant effects induced by HspB5 polypeptides towards HspB1. The R120G mutation enhanced the native size and salt resistance of HspB1-HspB5 complex. However, in oxidative conditions the interaction between HspB1 and mutant HspB5 was drastically modified resulting in the aggregation of both partners. The mutation also induced the redistribution of HspB1 phosphorylated at serine 15, originally observed at the level of the small oligomers that do not interact with wild type HspB5, to the large oligomeric complex formed with mutant HspB5. This phosphorylation stabilized the interaction of HspB1 with mutant HspB5. A dominant negative effect towards HspB1 appears therefore as an important event in the cellular sensitivity to oxidative stress mediated by mutated HspB5 expression. These observations provide novel data that describe how a mutated sHsp can alter the protective activity of another member of this family of chaperones.
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Affiliation(s)
- Stéphanie Simon
- Hôpital Henri Mondor University, Créteil, France
- CGphiMC, CNRS UMR 5534, Claude Bernard University Lyon 1, Villeurbanne, France
| | - Valeriya Dimitrova
- Department of Clinical Research, Division of Pediatric Hematology/Oncology, Insel Spital, Institute of Pathology, Bern University, Bern, Switzerland
- CGphiMC, CNRS UMR 5534, Claude Bernard University Lyon 1, Villeurbanne, France
| | - Benjamin Gibert
- CGphiMC, CNRS UMR 5534, Claude Bernard University Lyon 1, Villeurbanne, France
- Apoptosis Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Centre Léon Bérard, Claude Bernard University Lyon 1, Lyon, France
| | - Sophie Virot
- CGphiMC, CNRS UMR 5534, Claude Bernard University Lyon 1, Villeurbanne, France
| | - Nicole Mounier
- CGphiMC, CNRS UMR 5534, Claude Bernard University Lyon 1, Villeurbanne, France
| | - Mathieu Nivon
- CGphiMC, CNRS UMR 5534, Claude Bernard University Lyon 1, Villeurbanne, France
| | - Carole Kretz-Remy
- CGphiMC, CNRS UMR 5534, Claude Bernard University Lyon 1, Villeurbanne, France
| | - Véronique Corset
- Apoptosis Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Centre Léon Bérard, Claude Bernard University Lyon 1, Lyon, France
| | - Patrick Mehlen
- Apoptosis Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Centre Léon Bérard, Claude Bernard University Lyon 1, Lyon, France
| | - André-Patrick Arrigo
- CGphiMC, CNRS UMR 5534, Claude Bernard University Lyon 1, Villeurbanne, France
- Apoptosis Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Centre Léon Bérard, Claude Bernard University Lyon 1, Lyon, France
- * E-mail:
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169
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Young PR. Perspective on the Discovery and Scientific Impact of p38 MAP Kinase. ACTA ACUST UNITED AC 2013; 18:1156-63. [DOI: 10.1177/1087057113497401] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
It has now been almost 20 years since the discovery of p38 MAP kinase and its role in inflammatory cytokine synthesis through reverse pharmacology and its subsequent exploration as a potential target for autoimmune and other diseases. At the time of its discovery, the use of cell-based phenotypic screens to identify new molecular targets was at its infancy, and while p38 MAP kinase was not the first target to be identified this way, it provides a useful model for reviewing the pros and cons of this approach and the subsequent impact it can have on discovering new medicines.
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170
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Yego ECK, Dillman JF. Cytokine regulation by MAPK activated kinase 2 in keratinocytes exposed to sulfur mustard. Toxicol In Vitro 2013; 27:2067-75. [PMID: 23851002 DOI: 10.1016/j.tiv.2013.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 07/01/2013] [Accepted: 07/02/2013] [Indexed: 12/18/2022]
Abstract
Uncontrolled inflammation contributes to cutaneous damage following exposure to the warfare agent bis(2-chloroethyl) sulfide (sulfur mustard, SM). Activation of the p38 mitogen activated protein kinase (MAPK) precedes SM-induced cytokine secretion in normal human epidermal keratinocytes (NHEKs). This study examined the role of p38-regulated MAPK activated kinase 2 (MK2) during this process. Time course analysis studies using NHEK cells exposed to 200μM SM demonstrated rapid MK2 activation via phosphorylation that occurred within 15 min. p38 activation was necessary for MK2 phosphorylation as determined by studies using the p38 inhibitor SB203580. To compare the role of p38 and MK2 during SM-induced cytokine secretion, small interfering RNA (siRNA) targeting these proteins was utilized. TNF-α, IL-1β, IL-6 and IL-8 secretion was evaluated 24h postexposure, while mRNA changes were quantified after 8h. TNF-α, IL-6 and IL-8 up regulation at the protein and mRNA level was observed following SM exposure. IL-1β secretion was also elevated despite unchanged mRNA levels. p38 knockdown reduced SM-induced secretion of all the cytokines examined, whereas significant reduction in SM-induced cytokine secretion was only observed with TNF-α and IL-6 following MK2 knockdown. Our observations demonstrate potential activation of other p38 targets in addition to MK2 during SM-induced cytokine secretion.
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Affiliation(s)
- E Chepchumba K Yego
- Cell and Molecular Biology Branch, US Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, 21010 MD, United States.
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171
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Clarke JP, Mearow KM. Cell stress promotes the association of phosphorylated HspB1 with F-actin. PLoS One 2013; 8:e68978. [PMID: 23874834 PMCID: PMC3707891 DOI: 10.1371/journal.pone.0068978] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 06/10/2013] [Indexed: 01/18/2023] Open
Abstract
Previous studies have suggested that the small heat shock protein, HspB1, has a direct influence on the dynamics of cytoskeletal elements, in particular, filamentous actin (F-actin) polymerization. In this study we have assessed the influence of HspB1 phosphorylation on its interaction(s) with F-actin. We first determined the distribution of endogenous non-phosphorylated HspB1, phosphorylated HspB1 and F-actin in neuroendocrine PC12 cells by immunocytochemistry and confocal microscopy. We then investigated a potential direct interaction between HspB1 with F-actin by precipitating F-actin directly with biotinylated phalloidin followed by Western analyses; the reverse immunoprecipitation of HspB1 was also carried out. The phosphorylation influence of HspB1 in this interaction was investigated by using pharmacologic inhibition of p38 MAPK. In control cells, HspB1 interacts with F-actin as a predominantly non-phosphorylated protein, but subsequent to stress there is a redistribution of HspB1 to the cytoskeletal fraction and a significantly increased association of pHspB1 with F-actin. Our data demonstrate HspB1 is found in a complex with F-actin both in phosphorylated and non-phosphorylated forms, with an increased association of pHspB1 with F-actin after heat stress. Overall, our study combines both cellular and biochemical approaches to show cellular localization and direct demonstration of an interaction between endogenous HspB1 and F-actin using methodolgy that specifically isolates F-actin.
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Affiliation(s)
- Joseph P Clarke
- Division of Biomedical Sciences, Neurosciences Graduate Program, Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
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172
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Shiragami R, Murata S, Kosugi C, Tezuka T, Yamazaki M, Hirano A, Yoshimura Y, Suzuki M, Shuto K, Koda K. Enhanced antitumor activity of cerulenin combined with oxaliplatin in human colon cancer cells. Int J Oncol 2013; 43:431-8. [PMID: 23754252 DOI: 10.3892/ijo.2013.1978] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 04/05/2013] [Indexed: 11/06/2022] Open
Abstract
Fatty acid synthase is highly expressed in many types of human cancers. Cerulenin, a natural inhibitor of fatty acid synthase, induced apoptosis in the human colon cancer cell lines HCT116 and RKO. Oxaliplatin also induced cell death in these cell lines. Cerulenin treatment was associated with reduced levels of phosphorylated Akt, activation of p38 and induced caspase-3 cleavage and finally caused apoptosis. Oxaliplatin induced activation of the p53-p21 pathway and p38. In combination with cerulenin and oxaliplatin, activation of the p53-p21 pathway and p38 occurred in a smaller concentration and finally induced caspase-3 cleavage in a smaller concentration of cerulenin and oxaliplatin. In xenotransplanted SCID mice, the cerulenin + oxaliplatin group significantly inhibited tumor progression compared to the control, cerulenin and oxaliplatin groups. Based on these studies, inhibiting fatty acid synthase would be an effective strategy to treat unresectable colorectal cancer tumors in combination with oxaliplatin. Fatty acid synthase inhibitor would be one of the best counterparts of oxaliplatin, which reduces the dose and side-effects of oxaliplatin and would make it possible to endure the chemotherapy over a longer period.
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Affiliation(s)
- Risa Shiragami
- Department of Surgery, Teikyo University Chiba Medical Center, Ichihara, Chiba 299-0111, Japan
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173
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Arrigo AP, Gibert B. Protein interactomes of three stress inducible small heat shock proteins: HspB1, HspB5 and HspB8. Int J Hyperthermia 2013; 29:409-22. [DOI: 10.3109/02656736.2013.792956] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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174
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Aggeli IK, Koustas E, Gaitanaki C, Beis I. Curcumin acts as a pro-oxidant inducing apoptosis via JNKs in the isolated perfused Rana ridibunda heart. ACTA ACUST UNITED AC 2013; 319:328-39. [PMID: 23630153 DOI: 10.1002/jez.1797] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 03/26/2013] [Accepted: 04/01/2013] [Indexed: 02/05/2023]
Abstract
Amphibians are known to better tolerate and endure adverse environmental conditions such as redox imbalances conferred by reactive oxygen species (ROS), compared to mammals. Interestingly, the exact adaptation strategies and signaling mechanisms mediating these effects have not been fully elucidated. Therefore, in the present study, we probed into the molecular response of the isolated perfused Rana ridibunda heart to curcumin, in the context of mitogen-activated protein kinases (MAPKs) phosphorylation patterns and apoptotic markers occurrence. In particular, this polyphenol was found to exert a pro-oxidant effect in our model and to significantly upregulate p38-MAPK and JNKs phosphorylation (thus activation). The early apoptosis observed, substantiated by poly(ADP-ribose) polymerase (PARP) cleavage, was established to be JNKs- and ROS-mediated, while no involvement of p38-MAPK was detected. Subsequently, the pro-oxidative activity of curcumin was confirmed to mimic H(2) O(2). Furthermore, NADPH oxidase as well as Na(+) /K(+) -ATPase were found to mediate JNKs phosphorylation as well as PARP proteolytic cleavage. Curcumin exerts pleiotropic actions, both beneficial and detrimental and is currently the subject of intense scientific research. Being a low-molecular-weight antioxidant, it is intriguing to investigate curcumin's role in redox homeostasis in the amphibian heart, under conditions that apparently favor its pro-oxidative properties. Comparative studies of its multifaceted role in different species may contribute to the clarification of the signaling mechanisms it triggers and the terminal physiological response it confers. Collectively, this is to our knowledge, the first time that the signal transduction pathways stimulated by curcumin have been assessed in a non-mammalian species.
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Affiliation(s)
- Ioanna-Katerina Aggeli
- Department of Animal and Human Physiology, School of Biology, University of Athens, Panepistimioupolis, Athens, Greece
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175
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Gibert B, Simon S, Dimitrova V, Diaz-Latoud C, Arrigo AP. Peptide aptamers: tools to negatively or positively modulate HSPB1(27) function. Philos Trans R Soc Lond B Biol Sci 2013; 368:20120075. [PMID: 23530261 DOI: 10.1098/rstb.2012.0075] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Human HSP27 (HSPB1) is a molecular chaperone sensor which, through dynamic changes in its phosphorylation and oligomerization, allows cells to adapt to changes in their physiology and/or mount a protective response to injuries. In pathological conditions, the high level of HSPB1 expression can either be beneficial, such as in diseases characterized by cellular degenerations, or be malignant in cancer cells where it promotes tumourigenesis, metastasis and anti-cancer drug resistance. Structural changes allow HSPB1 to interact with specific client protein partners in order to modulate their folding/activity and/or half-life. Therefore, the search is open for therapeutic compounds aimed at either down- or upregulating HSPB1 activity. In this respect, we have previously described two peptide aptamers (PA11 and PA50) that specifically interact with HSPB1 small oligomers and decrease its anti-apoptotic and tumourigenic activities. A novel analysis of the different HSPB1-interacting aptamers that were isolated earlier revealed that one aptamer (PA23) has the intriguing ability to stimulate the protective activity of HSPB1. We show here that this aptamer abolishes the dominant negative effect induced by the R120G mutant of αB-crystallin (HSPB5) by disrupting its interaction with HSPB1. Hence, developing structure-based interfering strategies could lead to the discovery of HSPB1-based therapeutic drugs.
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Affiliation(s)
- Benjamin Gibert
- Apoptosis Cancer and Development Laboratory, Lyon Cancer Research Center, Centre Léon Bérard, INSERM U1052-CNRS 5238, University of Lyon, 69008 Lyon, France
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176
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Lee JH, Lee SW, Choi SH, Kim SH, Kim WJ, Jung JY. p38 MAP kinase and ERK play an important role in nitric oxide-induced apoptosis of the mouse embryonic stem cells. Toxicol In Vitro 2013; 27:492-8. [DOI: 10.1016/j.tiv.2012.07.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 07/18/2012] [Accepted: 07/24/2012] [Indexed: 10/28/2022]
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177
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Tsai YR, Huang LJ, Lin HY, Hung YJ, Lee MR, Kuo SC, Hsu MF, Wang JP. Inhibition of formyl peptide-stimulated superoxide anion generation by Fal-002-2 occurs mainly through the blockade of the p21-activated kinase and protein kinase C signaling pathways in ratneutrophils. Eur J Pharmacol 2013; 701:114-23. [PMID: 23357556 DOI: 10.1016/j.ejphar.2013.01.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 11/30/2012] [Accepted: 01/16/2013] [Indexed: 10/27/2022]
Abstract
In formyl-Met-Leu-Phe (fMLP)-stimulated rat neutrophils, a synthetic compound, 6-chloro-2-(2-chlorophenyl)-4-oxo-1,4-dihydroquinoline-3-carboxylate (Fal-002-2), inhibited superoxide anion (O2(•-)) generation with an IC50 value of about 11μM, which was not mediated by scavenging the generated O2(•-) or by a cytotoxic effect on neutrophils. Fal-002-2 effectively attenuated the phosphorylation of Ser residues in p47(phox) and the association between p47(phox) and p22(phox) in fMLP-stimulated neutrophils. The interaction of p47(phox) with protein kinase C (PKC) isoforms (α, βI, βII, δ and ζ) was attenuated by Fal-002-2 with a similar IC50 value to that required for inhibition of O2(•-) generation, whereas Fal-002-2 had no prominent effect on PKC isoform membrane translocation and did not affect the kinase activity. Moreover, Fal-002-2 had no effect on the phosphorylation of Akt and downstream glycogen synthase kinase-3β, only slightly affected the intracellular free Ca(2+) concentration, phosphorylation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase (MAPK), but effectively attenuated the downstream MAPK-activated protein kinase-2 phosphorylation. The interaction of p21-activated kinase (PAK) 1with p47(phox), phosphorylation of PAK1 (Thr423/Ser144) and the membrane recruitment of PAK1 were effectively inhibited by Fal-002-2. Fal-002-2 also blocked the activation of Rac1 and Cdc42 in a concentration range that effectively inhibited PAK activation. Taken together, these results suggest that Fal-002-2 inhibits fMLP-stimulated O2(•-) generation in neutrophils mainly through the blockade of PKC and PAK signaling pathways and partly through p38 MAPK signaling.
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Affiliation(s)
- Ya-Ru Tsai
- Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan, Republic of China
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178
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Jensen KJ, Garmaroudi FS, Zhang J, Lin J, Boroomand S, Zhang M, Luo Z, Yang D, Luo H, McManus BM, Janes KA. An ERK-p38 subnetwork coordinates host cell apoptosis and necrosis during coxsackievirus B3 infection. Cell Host Microbe 2013; 13:67-76. [PMID: 23332156 DOI: 10.1016/j.chom.2012.11.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 08/30/2012] [Accepted: 11/12/2012] [Indexed: 11/17/2022]
Abstract
The host response to a virus is determined by intracellular signaling pathways that are modified during infection. These pathways converge as networks and produce interdependent phenotypes, making it difficult to link virus-induced signals and responses at a systems level. Coxsackievirus B3 (CVB3) infection induces death of cardiomyocytes, causing tissue damage and virus dissemination, through incompletely characterized host cell signaling networks. We built a statistical model that quantitatively predicts cardiomyocyte responses from time-dependent measurements of phosphorylation events modified by CVB3. Model analysis revealed that CVB3-stimulated cytotoxicity involves tight coupling between the host ERK and p38 MAPK pathways, which are generally thought to control distinct cellular responses. The kinase ERK5 requires p38 kinase activity and inhibits apoptosis caused by CVB3 infection. By contrast, p38 indirectly promotes apoptosis via ERK1/2 inhibition but directly causes CVB3-induced necrosis. Thus, the cellular events governing pathogenesis are revealed when virus-host programs are monitored systematically and deconvolved mathematically.
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Affiliation(s)
- Karin J Jensen
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
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179
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Phosphorylation of epidermal growth factor receptor at serine 1047 by MAP kinase-activated protein kinase-2 in cultured lung epithelial cells treated with flagellin. Arch Biochem Biophys 2013; 529:75-85. [DOI: 10.1016/j.abb.2012.11.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 11/16/2012] [Accepted: 11/17/2012] [Indexed: 11/23/2022]
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180
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181
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Mavropoulos A, Orfanidou T, Liaskos C, Smyk DS, Billinis C, Blank M, Rigopoulou EI, Bogdanos DP. p38 mitogen-activated protein kinase (p38 MAPK)-mediated autoimmunity: lessons to learn from ANCA vasculitis and pemphigus vulgaris. Autoimmun Rev 2012. [PMID: 23207287 DOI: 10.1016/j.autrev.2012.10.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Evidence is beginning to accumulate that p38 mitogen activated protein kinase (p38 MAPK) signaling pathway plays an important role in the regulation of cellular and humoral autoimmune responses. The exact mechanisms and the degree by which the p38 MAPK pathway participates in the immune-mediated induction of diseases have started to emerge. This review discusses the recent advances in the molecular dissection of the p38 MAPK pathway and the findings generated by reports investigating its role in the pathogenesis of autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and autoimmune hepatitis. Application of newly-developed protocols based on sensitive flow cytometric detection has proven to be a useful tool in the investigation of the phosphorylation of p38 MAPK within different peripheral blood mononuclear cell populations and may help us to better understand the enigmatic role of this signaling cascade in the induction of autoimmunity as well as its role in immunosuppressive-induced remission. Special attention is paid to reported data proposing a specific role for autoantibody-induced activation of p38 MAPK-mediated immunopathology in the pathogenesis of autoimmune blistering diseases and anti-neutrophilic antibody-mediated vasculitides.
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Affiliation(s)
- Athanasios Mavropoulos
- Institute of Liver Studies, King's College London School of Medicine at King's College Hospital, Denmark Hill Campus, London SE5 9RS, UK
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182
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Zhao L, Wang JL, Wang YR, Fa XZ. Apigenin attenuates copper-mediated β-amyloid neurotoxicity through antioxidation, mitochondrion protection and MAPK signal inactivation in an AD cell model. Brain Res 2012. [PMID: 23178511 DOI: 10.1016/j.brainres.2012.11.019] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Apigenin, belonging to a less toxic and non-mutagenic flavone subclass of flavonoids, has been reported to possess numerous biological activities beneficial to health. Although evidence has shown apigenin might exert its protective effects by reducing the toxicity induced by amyloid-β peptides (Aβ), the precise mechanism is unclear. In the present study, we investigated the in vitro neuroprotective activity of apigenin interrelated with amyloid toxicity and mental homeostasis in an Alzheimer's disease (AD) cell model and explored its potential signal transduction. Our results showed that apigenin protected neurons against Aβ-mediated toxicity induced by copper, which was characterized by increasing neuronal viability and relieving mitochondrial membrane dissipation and neuronal nuclear condensation. Further, we demonstrated that apigenin did not provide sufficient effect on decreasing β-amyloid precursor protein (AβPP) expression and lowering Aβ(1-42) secretion, but conserved redox balance by increasing intracellular glutathione levels and enhancing cellular superoxide dismutase and glutathione peroxidase activities, reduced intracellular reactive oxygen species (ROS) generation, blocked ROS-induced p38 mitogen-activated protein kinases (p38 MAPK)- MAPKAP kinase-2 (MK2)-heat shock protein 27 (Hsp27) and stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK)-c-Jun signaling pathways, preserved mitochondrial function, and then regulated apoptotic pathways. In conclusion, apigenin could exert neuroprotection against Aβ-induced toxicity in the presence of copper mainly through the mechanisms that regulate redox imbalance, preserve mitochondrial function, inhibit MAPK pathways, and depress neuronal apoptosis.
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Affiliation(s)
- Le Zhao
- College of Life and Environmental Sciences, Minzu University of China, 27 South Street, Zhongguancun Beijing 100081, PR China
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183
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Survival of cancer stem cells under hypoxia and serum depletion via decrease in PP2A activity and activation of p38-MAPKAPK2-Hsp27. PLoS One 2012. [PMID: 23185379 PMCID: PMC3502468 DOI: 10.1371/journal.pone.0049605] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Hypoxia and serum depletion are common features of solid tumors that occur upon antiangiogenesis, irradiation and chemotherapy across a wide variety of malignancies. Here we show that tumor cells expressing CD133, a marker for colorectal cancer initiating or stem cells, are enriched and survive under hypoxia and serum depletion conditions, whereas CD133− cells undergo apoptosis. CD133+ tumor cells increase cancer stem cell and epithelial-mesenchymal transition properties. Moreover, via screening a panel of tyrosine and serine/threonine kinase pathways, we identified Hsp27 is constitutively activated in CD133+ cells rather than CD133− cell under hypoxia and serum depletion conditions. However, there was no difference in Hsp27 activation between CD133+ and CD133− cells under normal growth condition. Hsp27 activation, which was mediated by the p38MAPK-MAPKAPK2-Hsp27 pathway, is required for CD133+ cells to inhibit caspase 9 and 3 cleavage. In addition, inhibition of Hsp27 signaling sensitizes CD133+ cells to hypoxia and serum depletion -induced apoptosis. Moreover, the antiapoptotic pathway is also activated in spheroid culture-enriched CD133+ cancer stem cells from a variety of solid tumor cells including lung, brain and oral cancer, suggesting it is a common pathway activated in cancer stem cells from multiple tumor types. Thus, activation of PP2A or inactivation of the p38MAPK-MAPKAPK2-Hsp27 pathway may develop new strategies for cancer therapy by suppression of their TIC population.
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184
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Chen SF, Nieh S, Jao SW, Liu CL, Wu CH, Chang YC, Yang CY, Lin YS. Quercetin suppresses drug-resistant spheres via the p38 MAPK-Hsp27 apoptotic pathway in oral cancer cells. PLoS One 2012; 7:e49275. [PMID: 23152886 PMCID: PMC3495857 DOI: 10.1371/journal.pone.0049275] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 10/08/2012] [Indexed: 01/08/2023] Open
Abstract
Background Treatment failure in oral squamous cell carcinoma (OSCC) leading to local recurrence(s) and metastases is mainly due to drug resistance. Cancer stem cells (CSCs) are thought be responsible for the development of drug resistance. However, the correlations between CSCs, drug resistance, and new strategy against drug resistance in OSCC remain elusive. Methods A drug-resistant sphere (DRSP) model was generated by using a nonadhesive culture system to induce drug-resistant cells from SCC25 oral cancer cells. A comparative analysis was performed between the parent control cells and DRSPs with a related treatment strategy focusing on the expression of epithelial–mesenchymal transition (EMT)-associated markers, drug-resistance-related genes, and CSC properties in vitro, as well as tumorigenicity and the regimen for tumor regression in vivo. Results Our data show the presence of a phenomenon of EMT with gradual cellular transition from an epithelioid to mesenchymal-like spheroid morphology during induction of drug resistance. The characterization of DRSPs revealed the upregulation of the drug-resistance-related genes ABCG2 and MDR-1 and of CSC-representative markers, suggesting that DRSPs have greater resistance to cisplatin (Cis) and stronger CSC properties compared with the control. Moreover, overexpression of phosphorylated heat-shock protein 27 (p-Hsp27) via the activation of p38 MAPK signaling was observed in DRSPs. Knockdown of Hsp27 decreased Cis resistance and induced apoptosis in DRSPs. Furthermore, an inhibitor of Hsp27, quercetin (Qu), suppressed p-Hsp27 expression, with alterations of the EMT signature, leading to the promotion of apoptosis in DRSPs. A xenographic study also confirmed the increase of tumorigenicity in DRSPs. The combination of Qu and Cis can reduce tumor growth and decrease drug resistance in OSCC. Conclusions The p38 MAPK–Hsp27 axis plays an important role in CSCs-mediated drug resistance in OSCC. Targeting this axis using Qu combined with Cis may be a treatment strategy to improve prognosis in patients with OSCC.
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Affiliation(s)
- Su-Feng Chen
- Department of Dental Hygiene, China Medical University, Taichung, Taiwan
| | - Shin Nieh
- Department of Pathology, Tri-Service General Hospital & National Defense Medical Center, Taipei, Taiwan
- * E-mail: (SN); (Y-SL)
| | - Shu-Wen Jao
- Division of Colon and Rectal Surgery, Tri-Service General Hospital & National Defense Medical Center, Taipei, Taiwan
| | - Chia-Lin Liu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Chien-Hua Wu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Yun-Ching Chang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Chin-Yuh Yang
- Department of Dentistry, Shuang Ho Hospital & Taipei Medical University, Taipei, Taiwan
| | - Yaoh-Shiang Lin
- Department of Otolaryngology-Head and Neck Surgery, Tri-Service General Hospital & National Defense Medical Center, Taipei, Taiwan
- Department of Otolaryngology-Head and Neck Surgery, Chung Shan Medical University, Taichung, Taiwan
- * E-mail: (SN); (Y-SL)
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185
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Osgood MJ, Flynn CR, Komalavilas P, Brophy C. Cell-permeant peptide inhibitors of vasospasm and intimal hyperplasia. Vascular 2012; 21:46-53. [PMID: 23104826 DOI: 10.1258/vasc.2011.201203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Outcomes from vein graft bypass are limited by graft failure, leading causes of which include intimal hyperplasia and vasospasm. Intimal hyperplasia remains the most common cause of graft failure, but no therapeutic modalities have been shown to prevent intimal hyperplasia in humans. The small heat shock proteins are a class of naturally occurring proteins in vascular smooth muscle. These proteins have an integral role in maintenance of vascular tone and in cellular defense against various stressors. Transduction domains have enabled intracellular therapeutic delivery of peptide analogs of heat shock proteins, as well as peptide inhibitors of the kinases that phosphorylate these proteins. These cell-permeant peptides have been shown to prevent vasospasm and intimal hyperplasia in vitro. Since vascular bypass using vein grafts is analogous to autologous organ transplantation, ex vivo treatment of the vein graft with cell-permeant peptide inhibitors of vasospasm and intimal hyperplasia prior to implantation provides a unique opportunity for targeted treatment of the graft to improve patency.
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Affiliation(s)
- Michael J Osgood
- Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.
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186
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Arrigo AP. Pathology-dependent effects linked to small heat shock proteins expression: an update. SCIENTIFICA 2012; 2012:185641. [PMID: 24278676 PMCID: PMC3820616 DOI: 10.6064/2012/185641] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 09/17/2012] [Indexed: 06/02/2023]
Abstract
Small heat shock proteins (small Hsps) are stress-induced molecular chaperones that act as holdases towards polypeptides that have lost their folding in stress conditions or consequently of mutations in their coding sequence. A cellular protection against the deleterious effects mediated by damaged proteins is thus provided to cells. These chaperones are also highly expressed in response to protein conformational and inflammatory diseases and cancer pathologies. Through specific and reversible modifications in their phospho-oligomeric organization, small Hsps can chaperone appropriate client proteins in order to provide cells with resistance to different types of injuries or pathological conditions. By helping cells to better cope with their pathological status, their expression can be either beneficial, such as in diseases characterized by pathological cell degeneration, or deleterious when they are required for tumor cell survival. Moreover, small Hsps are actively released by cells and can act as immunogenic molecules that have dual effects depending on the pathology. The cellular consequences linked to their expression levels and relationships with other Hsps as well as therapeutic strategies are discussed in view of their dynamic structural organization required to interact with specific client polypeptides.
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Affiliation(s)
- A.-P. Arrigo
- Apoptosis Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Centre Léon Bérard, Claude Bernard University Lyon1, 28 Rue Laennec, 69008 Lyon, France
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187
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Abstract
PURPOSE The 27-kDa heat shock protein (HSP27) has been implicated in wound healing in multiple tissues. We investigated the expression and localization of phosphorylated HSP27 during epithelial wound healing in the murine cornea. METHODS Corneas of 8- to 10-week-old C57BL6 mice were wounded by epithelial debridement (n = 40). Unwounded corneas served as controls (n = 3). After 3, 7, and 14 days, phosphorylated HSP27 localization in wounded corneas was observed by confocal immunohistochemistry and double immunogold labeling transmission immunoelectron microscopy. Western blot analysis was performed to determine expression levels of phosphorylated HSP27 in scraped epithelia. Phosphorylated HSP27 localization was also separately performed with confocal immunohistochemistry 8 hours after epithelial debridement to investigate the early epithelial wound-healing process. RESULTS In unwounded corneas, phosphorylated HSP27 was localized only to the superficial epithelium. In contrast, phosphorylated HSP27 was localized in the basal and superficial epithelia 3 days after corneal epithelial wounding. After 7 and 14 days, HSP27 localization was similar to that in unwounded controls. Expression levels of phosphorylated HSP27 were greater in wounded corneal epithelia on day 3 than in unwounded controls and on day 14. After 8 hours, phosphorylated HSP27 expression was prominent in the leading edge of migrating corneal epithelium. CONCLUSIONS Constitutive expression of phosphorylated HSP27 is limited to the superficial corneal epithelium in unwounded murine corneas. Changes in HSP27 epithelial distribution and expression levels after corneal epithelial wounding suggest that phosphorylated HSP27 plays a role in early phase of corneal epithelial wound healing.
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188
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Lin SP, Lee YT, Yang SH, Miller SA, Chiou SH, Hung MC, Hung SC. Colon cancer stem cells resist antiangiogenesis therapy-induced apoptosis. Cancer Lett 2012; 328:226-34. [PMID: 23017941 DOI: 10.1016/j.canlet.2012.08.036] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 08/30/2012] [Accepted: 08/31/2012] [Indexed: 12/22/2022]
Abstract
Antiangiogenesis is an efficient therapy for eliminating colon cancers, but because of recurrence it remains only palliative. We hypothesized that certain populations of tumor cells resist antiangiogenesis-induced apoptosis and explored the underlying mechanism. We demonstrated that the CD133(+) population of cells in colon cancer is resistant to anti-angiogenesis therapy. Additionally, we identified an anti-apoptotic signaling pathway responsible for this resistance involving PP2A, p38MAPK, MAPKAPK2, and Hsp27. Thus, this pathway may offer a new avenue to develop target therapy for colorectal cancer.
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Affiliation(s)
- Shih-Pei Lin
- Institute of Clinical Medicine, Faculty of Medicine, National Yang-Ming University, Taipei 112, Taiwan
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189
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Chen P, Kartha S, Bissonnette M, Hart J, Toback FG. AMP-18 facilitates assembly and stabilization of tight junctions to protect the colonic mucosal barrier. Inflamm Bowel Dis 2012; 18:1749-59. [PMID: 22271547 PMCID: PMC3337967 DOI: 10.1002/ibd.22886] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 12/28/2011] [Indexed: 12/11/2022]
Abstract
BACKGROUND Inflammatory bowel disease (IBD) is characterized by an injured epithelium. Development of agents that could enhance mucosal healing is a major goal in IBD therapeutics. The 18-kDa antrum mucosal protein (AMP-18) and a 21-mer peptide derived from AMP-18 stimulate accumulation of tight junction (TJ) proteins in cultured epithelial cells and mouse colonic mucosa to protect the mucosal barrier, suggesting it might be a useful agent to treat IBD. METHODS We searched for molecular mechanisms by which AMP peptide or recombinant AMP-18 act on TJs in intact cell monolayers, or those disrupted by low-calcium medium. Roles of the p38 mitogen-activated protein kinase (MAPK) / heat shock protein (hsp)25 pathway and PKCζ were investigated by immunoblotting and confocal microscopy. RESULTS AMP peptide activated p38 MAPK, which subsequently phosphorylated hsp25. Accumulated phospho-hsp25 was associated with perijunctional actin. AMP-18 also induced rapid phosphorylation of PKCζ and its colocalization with perijunctional actin in Caco2/bbe cells, which was accompanied by translocation and formation of complexes of "polarity proteins" in the TJ-containing detergent-insoluble fraction. Treatment with AMP-18 also stimulated accumulation of ZO-1, ZO-2, and JAM-A in nascent TJs known to associate with the multimeric p-PKCζ/Par6/ Cdc42/ECT2·GTP/Par3 polarity protein complex. CONCLUSIONS AMP-18 facilitates translocation and assembly of multiple proteins into TJs and their association with and subsequent stabilization of the actin filament network. We speculate that improved barrier function induced by AMP-18 is mediated by enhanced TJ assembly. Thus, AMP-18 may provide a promising lead to develop agents effective in healing injured colonic epithelium in IBD.
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Affiliation(s)
- Peili Chen
- Department of Medicine, University of Chicago, Illinois 60637
| | | | | | - John Hart
- Department of Pathology, University of Chicago, Illinois 60637
| | - F. Gary Toback
- Department of Medicine, University of Chicago, Illinois 60637
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190
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Azevedo R, van Zeeland M, Raaijmakers H, Kazemier B, de Vlieg J, Oubrie A. X-ray structure of p38α bound to TAK-715: comparison with three classic inhibitors. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2012; 68:1041-50. [PMID: 22868770 DOI: 10.1107/s090744491201997x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 05/03/2012] [Indexed: 11/11/2022]
Abstract
The p38α mitogen-activated protein kinase regulates the synthesis of pro-inflammatory cytokines in response to stimulation by a diverse set of stress signals. Various different chemotypes and clinical candidates that inhibit p38α function have been reported over the years. In this publication, the novel structure of p38α cocrystallized with the clinical candidate TAK-715 is reported. Owing to the impact of crystallization conditions on the conformation of protein kinases (and in particular p38α), the structures of complexes of p38α with SB-203580, SCIO-469 and VX-745 have also been determined to enable in-depth comparison of ligand-induced protein conformations. The impact of experimental conditions on p38α-inhibitor complex structures, most importantly soaking versus cocrystallization, is discussed. Analysis of the structures and quantification of the protein-ligand interactions couples ligand-induced protein conformations to the number of interactions and to inhibitor selectivity against the human kinome. This shows that for the design of novel kinase inhibitors, selectivity is best obtained through maximization of the number of interactions throughout the ATP pocket and the exploitation of specific features in the active site.
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Affiliation(s)
- Rita Azevedo
- Merck Research Laboratories, MSD, PO Box 20, 5340 BH Oss, The Netherlands
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191
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Kyriakis JM, Avruch J. Mammalian MAPK signal transduction pathways activated by stress and inflammation: a 10-year update. Physiol Rev 2012; 92:689-737. [PMID: 22535895 DOI: 10.1152/physrev.00028.2011] [Citation(s) in RCA: 994] [Impact Index Per Article: 82.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The mammalian stress-activated families of mitogen-activated protein kinases (MAPKs) were first elucidated in 1994, and by 2001, substantial progress had been made in identifying the architecture of the pathways upstream of these kinases as well as in cataloguing candidate substrates. This information remains largely sound. Nevertheless, an informed understanding of the physiological and pathophysiological roles of these kinases remained to be accomplished. In the past decade, there has been an explosion of new work using RNAi in cells, as well as transgenic, knockout and conditional knockout technology in mice that has provided valuable insight into the functions of stress-activated MAPK pathways. These findings have important implications in our understanding of organ development, innate and acquired immunity, and diseases such as atherosclerosis, tumorigenesis, and type 2 diabetes. These new developments bring us within striking distance of the development and validation of novel treatment strategies. Herein we first summarize the molecular components of the mammalian stress-regulated MAPK pathways and their regulation as described thus far. We then review some of the in vivo functions of these pathways.
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Affiliation(s)
- John M Kyriakis
- Molecular Cardiology Research Institute, Tufts Medical Center, 800 Washington St., Box 8486, Boston, MA 02111, USA.
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192
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The Role of p38 MAPK and Its Substrates in Neuronal Plasticity and Neurodegenerative Disease. JOURNAL OF SIGNAL TRANSDUCTION 2012; 2012:649079. [PMID: 22792454 PMCID: PMC3389708 DOI: 10.1155/2012/649079] [Citation(s) in RCA: 164] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 05/10/2012] [Indexed: 11/17/2022]
Abstract
A significant amount of evidence suggests that the p38-mitogen-activated protein kinase (MAPK) signalling cascade plays a crucial role in synaptic plasticity and in neurodegenerative diseases. In this review we will discuss the cellular localisation and activation of p38 MAPK and the recent advances on the molecular and cellular mechanisms of its substrates: MAPKAPK 2 (MK2) and tau protein. In particular we will focus our attention on the understanding of the p38 MAPK-MK2 and p38 MAPK-tau activation axis in controlling neuroinflammation, actin remodelling and tau hyperphosphorylation, processes that are thought to be involved in normal ageing as well as in neurodegenerative diseases. We will also give some insight into how elucidating the precise role of p38 MAPK-MK2 and p38 MAPK-tau signalling cascades may help to identify novel therapeutic targets to slow down the symptoms observed in neurodegenerative diseases such as Alzheimer's and Parkinson's disease.
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193
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Matesic DF, Sidorova TS, Burns TJ, Bell AM, Tran PL, Ruch RJ, May SW. p38 MAPK activation, JNK inhibition, neoplastic growth inhibition, and increased gap junction communication in human lung carcinoma and Ras-transformed cells by 4-phenyl-3-butenoic acid. J Cell Biochem 2012; 113:269-81. [PMID: 21898549 DOI: 10.1002/jcb.23353] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Human lung neoplasms frequently express mutations that down-regulate expression of various tumor suppressor molecules, including mitogen-activated protein kinases such as p38 MAPK. Conversely, activation of p38 MAPK in tumor cells results in cancer cell cycle inhibition or apoptosis initiated by chemotherapeutic agents such as retinoids or cisplatin, and is therefore an attractive approach for experimental anti-tumor therapies. We now report that 4-phenyl-3-butenoic acid (PBA), an experimental compound that reverses the transformed phenotype at non-cytotoxic concentrations, activates p38 MAPK in tumorigenic cells at concentrations and treatment times that correlate with decreased cell growth and increased cell-cell communication. H2009 human lung carcinoma cells and ras-transformed rat liver epithelial cells treated with PBA showed increased activation of p38 MAPK and its downstream effectors which occurred after 4 h and lasted beyond 48 h. Untransformed plasmid control cells showed low activation of p38 MAPK compared to ras-transformed and H2009 carcinoma cells, which correlates with the reduced effect of PBA on untransformed cell growth. The p38 MAPK inhibitor, SB203580, negated PBA's activation of p38 MAPK downstream effectors. PBA also increased cell-cell communication and connexin 43 phosphorylation in ras-transformed cells, which were prevented by SB203580. In addition, PBA decreased activation of JNK, which is upregulated in many cancers. Taken together, these results suggest that PBA exerts its growth regulatory effect in tumorigenic cells by concomitant up-regulation of p38 MAPK activity, altered connexin 43 expression, and down-regulation of JNK activity. PBA may therefore be an effective therapeutic agent in human cancers that exhibit down-regulated p38 MAPK activity and/or activated JNK and altered cell-cell communication.
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Affiliation(s)
- Diane F Matesic
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Mercer University, Atlanta, Georgia 30341, USA.
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194
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Small heat shock proteins and the cytoskeleton: an essential interplay for cell integrity? Int J Biochem Cell Biol 2012; 44:1680-6. [PMID: 22683760 DOI: 10.1016/j.biocel.2012.05.024] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 05/25/2012] [Accepted: 05/29/2012] [Indexed: 12/23/2022]
Abstract
The cytoskeleton is a highly complex network of three major intracellular filaments, microfilaments (MFs), microtubules (MTs) and intermediate filaments (IFs). This network plays a key role in the control of cell shape, division, functions and interactions in animal organs and tissues. Dysregulation of the network can contribute to numerous human diseases. Although small HSPs (sHSPs) and in particular HSP27 (HSPB1) or αB-crystallin (HSPB5) display a wide range of cellular properties, they are mostly known for their ability to protect cells under stress conditions. Mutations in some sHSPs have been found to affect their ability to interact with cytoskeleton proteins, leading to IF aggregation phenotypes that mimick diseases related to disorders in IF proteins (i.e. desmin, vimentin and neuro-filaments). The aim of this review is to discuss new findings that point towards the possible involvement of IFs in the cytoprotective functions of sHSPs, both in physiological and pathological settings, including the likelihood that sHSPs such as HSPB1 may play a role during epithelial-to-mesenchymal transition (EMT) during fibrosis or cancer progression. This article is part of a Directed Issue entitled: Small HSPs in physiology and pathology.
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195
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Yoshizuka N, Lai M, Liao R, Cook R, Xiao C, Han J, Sun P. PRAK suppresses oncogenic ras-induced hematopoietic cancer development by antagonizing the JNK pathway. Mol Cancer Res 2012; 10:810-20. [PMID: 22665523 DOI: 10.1158/1541-7786.mcr-11-0576] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The p38 mitogen-activated protein kinase (MAPK) pathway regulates multiple physiologic and pathologic processes, including cancer development. PRAK, a p38 substrate protein kinase, has previously been implicated in the suppression of skin carcinogenesis. In the current study, we show that PRAK deletion accelerates hematopoietic cancer development in a mouse model harboring an oncogenic ras allele, Eμ-N-Ras(G12D), specifically expressed in hematopoietic cells. Further investigation reveals that enhanced hematopoietic tumorigenesis by PRAK deficiency is associated with hyperactivation of the c-jun-NH(2)-kinase (JNK) pathway both in vivo and in primary hematopoietic cells isolated from spleens. In primary splenocytes, PRAK deficiency further enhanced oncogenic ras-induced cell proliferation and promoted ras-mediated colony formation on semisolid medium in a JNK-dependent manner. In addition, deletion of PRAK leads to abrogation of ras-induced accumulation of senescence markers. These findings indicate that PRAK suppresses hematopoietic cancer formation in this mouse model by antagonizing oncogenic ras-induced activation of the JNK pathway. Our results suggest that PRAK may function as a tumor suppressor in multiple types of cancers.
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Affiliation(s)
- Naoto Yoshizuka
- Department of Molecular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, USA
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196
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Cell type-specific targeting dissociates the therapeutic from the adverse effects of protein kinase inhibition in allergic skin disease. Proc Natl Acad Sci U S A 2012; 109:9089-94. [PMID: 22615377 DOI: 10.1073/pnas.1202984109] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The kinase p38α, originally identified because of its endotoxin- and cytokine-inducible activity and affinity for antiinflammatory compounds, has been posited as a promising therapeutic target for various immune-mediated disorders. In clinical trials, however, p38α inhibitors produced adverse skin reactions and other toxic effects that often outweighed their benefits. Such toxicity may arise from a perturbation of physiological functions unrelated to or even protective against the disease being treated. Here, we show that the effect of interfering with p38α signaling can be therapeutic or adverse depending on the targeted cell type. Using a panel of mutant mice devoid of p38α in distinct cell types and an experimental model of allergic skin disease, we find that dendritic cell (DC)-intrinsic p38α function is crucial for both antigen-specific T-cell priming and T-cell-mediated skin inflammation, two independent processes essential for the immunopathogenesis. By contrast, p38α in other cell types serves to prevent excessive inflammation or maintain naïve T-cell pools in the peripheral lymphoid tissues. These findings highlight a dilemma in the clinical use of p38α inhibitors, yet also suggest cell-selective targeting as a potential solution for improving their therapeutic index.
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197
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Szelenyi ER, Urso ML. Time-course analysis of injured skeletal muscle suggests a critical involvement of ERK1/2 signaling in the acute inflammatory response. Muscle Nerve 2012; 45:552-61. [PMID: 22431089 DOI: 10.1002/mus.22323] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
INTRODUCTION The coupling and timing of pro- and anti-inflammatory processes in skeletal muscle injury is poorly understood. We investigated the temporal response and regulated processes of extracellular signal-regulated kinases 1 and 2 (ERK1/2), p38, and IkappaB kinase (IKK) α/β signaling pathways after traumatic injury. METHODS Traumatic freeze injury was delivered to the tibialis anterior (TA) muscle in C57BL/6J mice, and injured and uninjured TA muscles were analyzed 3-72 h into the recovery period. RESULTS Significant increases in pro-inflammatory cytokine transcription accompanied IKKβ phosphorylation, robust ERK pathway activation, and reduced heat shock protein (Hsp) protein expression at 3-24 h. At 24 h, ERK activation was abolished concomitantly with a significant increase in mitogen-activated protein kinase phosphatase-1 (MKP-1). After 24 h, cytokine transcription along with ERK1/2 and IKKβ phosphorylation remained suppressed, whereas Hsp protein expression rose to significant levels by 72 h and associated with IKKβ. CONCLUSIONS Results indicate a bimodal regulation of ERK1/2 in acute inflammation in which it is supportive from 3 to 24 h, and suppressive from 24 to 72 h.
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Affiliation(s)
- Eric R Szelenyi
- U.S. Army Research Institute of Environmental Medicine, 42 Kansas Street, Building 42, Natick, Massachusetts 01760, USA
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198
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Parasynaptic NMDA receptor signaling couples neuronal glutamate transporter function to AMPA receptor synaptic distribution and stability. J Neurosci 2012; 32:2552-63. [PMID: 22396428 DOI: 10.1523/jneurosci.3237-11.2012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
At synapses, two major processes occur concomitantly after the release of glutamate: activation of AMPA receptors (AMPARs) to conduct synaptic transmission and activation of excitatory amino acid transporters (EAATs) for transmitter removal. Although crosstalk between the receptors and EAATs is conceivable, whether and how the transporter activity affects AMPAR synaptic localization remain unknown. Using cultured hippocampal and cortical rat neurons, we show that inhibition of glutamate transporters leads to rapid reduction in AMPAR synaptic accumulation and total AMPAR abundance. EAAT inactivity also results in elevated internalization and reduced surface expression of AMPARs. The reduction in AMPAR amount is accompanied by receptor ubiquitination and can be blocked by suppression of proteasome activity, indicating the involvement of proteasome-mediated receptor degradation. Consistent with glutamate spillover, effect of EAAT inhibition on AMPAR distribution and stability is dependent on the activation of parasynaptically localized NR2B-containing NMDA receptors (NMDARs). Moreover, we show that neuronal glutamate transporters, especially those localized at the postsynaptic sites, are responsible for the observed effect during EAAT suppression. These results indicate a role for neuron-specific glutamate transporters in AMPAR synaptic localization and stability.
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Role of Mitogen-Activated Protein Kinases in Myocardial Ischemia-Reperfusion Injury during Heart Transplantation. J Transplant 2012; 2012:928954. [PMID: 22530110 PMCID: PMC3316985 DOI: 10.1155/2012/928954] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 12/09/2011] [Accepted: 12/23/2011] [Indexed: 12/13/2022] Open
Abstract
In solid organ transplantation, ischemia/reperfusion (IR) injury during organ procurement, storage and reperfusion is an unavoidable detrimental event for the graft, as it amplifies graft inflammation and rejection. Intracellular mitogen-activated protein kinase (MAPK) signaling pathways regulate inflammation and cell survival during IR injury. The four best-characterized MAPK subfamilies are the c-Jun NH2-terminal kinase (JNK), extracellular signal- regulated kinase-1/2 (ERK1/2), p38 MAPK, and big MAPK-1 (BMK1/ERK5). Here, we review the role of MAPK activation during myocardial IR injury as it occurs during heart transplantation. Most of our current knowledge regarding MAPK activation and cardioprotection comes from studies of preconditioning and postconditioning in nontransplanted hearts. JNK and p38 MAPK activation contributes to myocardial IR injury after prolonged hypothermic storage. p38 MAPK inhibition improves cardiac function after cold storage, rewarming and reperfusion. Small-molecule p38 MAPK inhibitors have been tested clinically in patients with chronic inflammatory diseases, but not in transplanted patients, so far. Organ transplantation offers the opportunity of starting a preconditioning treatment before organ procurement or during cold storage, thus modulating early events in IR injury. Future studies will need to evaluate combined strategies including p38 MAPK and/or JNK inhibition, ERK1/2 activation, pre- or postconditioning protocols, new storage solutions, and gentle reperfusion.
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Hill ZB, Perera BGK, Andrews SS, Maly DJ. Targeting diverse signaling interaction sites allows the rapid generation of bivalent kinase inhibitors. ACS Chem Biol 2012; 7:487-95. [PMID: 22148755 DOI: 10.1021/cb200387g] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The identification of potent and selective modulators of protein kinase function remains a challenge, and new strategies are needed for generating these useful ligands. Here, we describe the generation of bivalent inhibitors of three unrelated protein kinases: the CAMK family kinase Pim1, the mitogen-activated protein kinase (MAPK) p38α, and the receptor tyrosine kinase (RTK) epidermal growth factor receptor (EGFR). These bivalent inhibitors consist of an ATP-competitive inhibitor that is covalently tethered to an engineered form of the self-labeling protein O(6)-alkylguanine-DNA alkyltransferase (SNAP-tag). In each example, SNAP-tag is fused to a peptide ligand that binds to a signaling interaction site of the kinase being targeted. These interactions increase the overall selectivity and potency of the bivalent inhibitors that were generated. The ability to exploit disparate binding sites in diverse kinases points to the generality of the method described. Finally, we demonstrate that ATP-competitive inhibitors that are conjugated to the bio-orthogonal tag O(4)-benzyl-2-chloro-6-aminopyrimidine (CLP) are cell-permeable. The selective labeling of SNAP-tag with CLP conjugates allows the rapid assembly of bivalent inhibitors in living cells.
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Affiliation(s)
- Zachary B. Hill
- Department
of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700,
United States
| | - B. Gayani K. Perera
- Department
of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700,
United States
| | - Simeon S. Andrews
- Department
of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700,
United States
| | - Dustin J. Maly
- Department
of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700,
United States
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