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Jiang Y, Li Y, Wang Y, Li X. Furanodienone induces apoptosis via regulating the PRDX1/MAPKs/p53/caspases signaling axis through NOX4-derived mitochondrial ROS in colorectal cancer cells. Biochem Pharmacol 2024; 227:116456. [PMID: 39079582 DOI: 10.1016/j.bcp.2024.116456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Revised: 07/03/2024] [Accepted: 07/25/2024] [Indexed: 08/04/2024]
Abstract
Furanodienone, a biologically active constituent of sesquiterpenes isolated from Rhizome Curcumae, has been reported to induce apoptosis in human colorectal cancer (CRC) cells by promoting the generation of reactive oxygen species (ROS). However, the source of ROS and how it manipulates apoptosis in CRC cells remains to be elucidated. Herein, we assessed the potential role of the well-known sources of intracellular ROS-mitochondrial electron transport chain and the nicotinamide adenine dinucleotide phosphate oxidases (NOXs), on furanodienone-induced cell death. The results indicated that furanodienone substantially increased the levels of mitochondrial ROS, which were subsequently eliminated by the general NOX inhibitor. Specifically, the nuclear factor kappa-B (NF-κB) translocation triggered a significant rise in the expression of NOX4, an isoform of the NOXs family, upon furanodienone treatment. Nevertheless, the specific NOX4 inhibitor GLX351322 attenuated cell apoptosis and mitochondrial ROS production. As a result, ROS burst induced by furanodienone suppressed the expression of peroxiredoxin1 (PRDX1), a redox signaling protein overexpressed in CRC cells, through a nuclear factor-erythroid-2-related factor 2 (Nrf2)-dependent pathway, thus amplifying the mitogen-activated protein kinases (MAPKs)/p53-mediated apoptotic signaling by increasing the p-p38, p-JNK levels, as well as the cleaved caspases -3, -8 and -9. In vivo experiments further confirmed the anti-proliferative impact of PRDX1 following furanodienone treatment. In summary, the study demonstrated that furanodienone-induced apoptosis in CRC cells is initiated by mitochondrial ROS derived from NOX4, which targeted the PRDX1 and activated the downstream MAPKs/p53-mediated caspase-dependent signaling pathway. Our findings may provide novel insights into the development of adjuvant drugs for CRC treatment and therapeutic applications.
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Affiliation(s)
- Ying Jiang
- Department of Pharmacy, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
| | - Yanli Li
- Department of Pharmacy, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
| | - Yuzhu Wang
- Department of Pharmacy, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
| | - Xiaoyu Li
- Department of Pharmacy, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
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2
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Wang Y, Hu S, Zhang W, Zhang B, Yang Z. Emerging role and therapeutic implications of p53 in intervertebral disc degeneration. Cell Death Discov 2023; 9:433. [PMID: 38040675 PMCID: PMC10692240 DOI: 10.1038/s41420-023-01730-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 11/11/2023] [Accepted: 11/16/2023] [Indexed: 12/03/2023] Open
Abstract
Lower back pain (LBP) is a common degenerative musculoskeletal disease that imposes a huge economic burden on both individuals and society. With the aggravation of social aging, the incidence of LBP has increased globally. Intervertebral disc degeneration (IDD) is the primary cause of LBP. Currently, IDD treatment strategies include physiotherapy, medication, and surgery; however, none can address the root cause by ending the degeneration of intervertebral discs (IVDs). However, in recent years, targeted therapy based on specific molecules has brought hope for treating IDD. The tumor suppressor gene p53 produces a transcription factor that regulates cell metabolism and survival. Recently, p53 was shown to play an important role in maintaining IVD microenvironment homeostasis by regulating IVD cell senescence, apoptosis, and metabolism by activating downstream target genes. This study reviews research progress regarding the potential role of p53 in IDD and discusses the challenges of targeting p53 in the treatment of IDD. This review will help to elucidate the pathogenesis of IDD and provide insights for the future development of precision treatments.
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Affiliation(s)
- Yidian Wang
- Department of Joint Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
| | - Shouye Hu
- Department of Joint Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Weisong Zhang
- Department of Joint Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Binfei Zhang
- Department of Joint Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Zhi Yang
- Department of Joint Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
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3
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Qin S, Kitty I, Hao Y, Zhao F, Kim W. Maintaining Genome Integrity: Protein Kinases and Phosphatases Orchestrate the Balancing Act of DNA Double-Strand Breaks Repair in Cancer. Int J Mol Sci 2023; 24:10212. [PMID: 37373360 DOI: 10.3390/ijms241210212] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
DNA double-strand breaks (DSBs) are the most lethal DNA damages which lead to severe genome instability. Phosphorylation is one of the most important protein post-translation modifications involved in DSBs repair regulation. Kinases and phosphatases play coordinating roles in DSB repair by phosphorylating and dephosphorylating various proteins. Recent research has shed light on the importance of maintaining a balance between kinase and phosphatase activities in DSB repair. The interplay between kinases and phosphatases plays an important role in regulating DNA-repair processes, and alterations in their activity can lead to genomic instability and disease. Therefore, study on the function of kinases and phosphatases in DSBs repair is essential for understanding their roles in cancer development and therapeutics. In this review, we summarize the current knowledge of kinases and phosphatases in DSBs repair regulation and highlight the advancements in the development of cancer therapies targeting kinases or phosphatases in DSBs repair pathways. In conclusion, understanding the balance of kinase and phosphatase activities in DSBs repair provides opportunities for the development of novel cancer therapeutics.
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Affiliation(s)
- Sisi Qin
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
| | - Ichiwa Kitty
- Department of Integrated Biomedical Science, Soonchunhyang Institute of Medi-Bio Science (SIMS), Soonchunhyang University, Cheonan 31151, Chungcheongnam-do, Republic of Korea
| | - Yalan Hao
- Analytical Instrumentation Center, Hunan University, Changsha 410082, China
| | - Fei Zhao
- College of Biology, Hunan University, Changsha 410082, China
| | - Wootae Kim
- Department of Integrated Biomedical Science, Soonchunhyang Institute of Medi-Bio Science (SIMS), Soonchunhyang University, Cheonan 31151, Chungcheongnam-do, Republic of Korea
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4
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Marques MA, de Andrade GC, Silva JL, de Oliveira GAP. Protein of a thousand faces: The tumor-suppressive and oncogenic responses of p53. Front Mol Biosci 2022; 9:944955. [PMID: 36090037 PMCID: PMC9452956 DOI: 10.3389/fmolb.2022.944955] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/18/2022] [Indexed: 12/30/2022] Open
Abstract
The p53 protein is a pleiotropic regulator working as a tumor suppressor and as an oncogene. Depending on the cellular insult and the mutational status, p53 may trigger opposing activities such as cell death or survival, senescence and cell cycle arrest or proliferative signals, antioxidant or prooxidant activation, glycolysis, or oxidative phosphorylation, among others. By augmenting or repressing specific target genes or directly interacting with cellular partners, p53 accomplishes a particular set of activities. The mechanism in which p53 is activated depends on increased stability through post-translational modifications (PTMs) and the formation of higher-order structures (HOS). The intricate cell death and metabolic p53 response are reviewed in light of gaining stability via PTM and HOS formation in health and disease.
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Affiliation(s)
- Mayra A. Marques
- *Correspondence: Mayra A. Marques, ; Guilherme A. P. de Oliveira,
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5
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Wang H, Zhang M, Xu X, Hou S, Liu Z, Chen X, Zhang C, Xu H, Wu L, Liu K, Song L. IKKα mediates UVB-induced cell apoptosis by regulating p53 pathway activation. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 227:112892. [PMID: 34649141 DOI: 10.1016/j.ecoenv.2021.112892] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 09/23/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
Exposure to ultraviolet B (UVB) has been demonstrated to induce DNA damage as well as angiogenesis-related photo-damages, which are implicated in a variety of medical problems, including sunburn, photo-aging and skin cancers. However, the molecular mechanism related to UVB-induced photo-injuries remained fully elucidated. Here we revealed that one of the catalytic subunits of the IKK complex, IKKα, played a critical role in mediating UVB-induced apoptotic responses in two kinds of UVB sensitive cells, human keratinocyte (HaCat) and mouse embryonic fibroblasts (MEFs). This function of IKKα was unrelated to NF-κB activity, but was delivered by inducing phosphorylation and acetylation of p53 and upregulating the expression of the pro-apoptotic p53 target gene, PERP. Although IKKα kinase activity was required for mediating post-translational modifications and transactivation of 53 and PERP induction, IKKα did not show direct binding ability toward p53. Instead, IKKα could interact with CHK1, the protein kinase leading to p53 phosphorylation, and trigger CHK1 activation and CHK1/p53 complex formation. At the same time, IKKα could also interact with p300 and CBP, the acetyltransferases responsible for p53 acetylation, and trigger p300/CBP activation and p300/p53 or CBP/p53 complex formation under UVB exposure. Taken together, we have identified a novel NF-κB-independent role of IKKα in mediating UVB-induced apoptosis by regulating p53 pathway activation. Targeting IKKα/p53/PERP pathway might be helpful to prevent skin photo-damages induced by sunlight.
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Affiliation(s)
- Hongli Wang
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China; Laboratory of Cellular and Molecular Immunology, School of Medicine, Henan University, 357 Ximen Road, Kaifeng 475004, China
| | - Min Zhang
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China
| | - Xiuduan Xu
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China; Anhui Medical University, 81 Meishan Road, Hefei 230032, China
| | - Shaojun Hou
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China; Anhui Medical University, 81 Meishan Road, Hefei 230032, China
| | - Zhihui Liu
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China; College of Life Science, Henan Normal University, 46 Jianshe Road, Xinxiang 473007, China
| | - Xuejiao Chen
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China
| | - Chongchong Zhang
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China; Laboratory of Cellular and Molecular Immunology, School of Medicine, Henan University, 357 Ximen Road, Kaifeng 475004, China
| | - Huan Xu
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China; Anhui Medical University, 81 Meishan Road, Hefei 230032, China
| | - Lin Wu
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China
| | - Kun Liu
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China
| | - Lun Song
- Beijing Institute of Basic Medical Sciences, 27 Taiping Road, Beijing 100850, China; Anhui Medical University, 81 Meishan Road, Hefei 230032, China; College of Life Science, Henan Normal University, 46 Jianshe Road, Xinxiang 473007, China; School of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, China.
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6
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Shi T, van Soest DMK, Polderman PE, Burgering BMT, Dansen TB. DNA damage and oxidant stress activate p53 through differential upstream signaling pathways. Free Radic Biol Med 2021; 172:298-311. [PMID: 34144191 DOI: 10.1016/j.freeradbiomed.2021.06.013] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/28/2021] [Accepted: 06/13/2021] [Indexed: 12/22/2022]
Abstract
Stabilization and activation of the p53 tumor suppressor are triggered in response to various cellular stresses, including DNA damaging agents and elevated Reactive Oxygen Species (ROS) like H2O2. When cells are exposed to exogenously added H2O2, ATR/CHK1 and ATM/CHK2 dependent DNA damage signaling is switched on, suggesting that H2O2 induces both single and double strand breaks. These collective observations have resulted in the widely accepted model that oxidizing conditions lead to DNA damage that subsequently mediates a p53-dependent response like cell cycle arrest and apoptosis. However, H2O2 also induces signaling through stress-activated kinases (SAPK, e.g., JNK and p38 MAPK) that can activate p53. Here we dissect to what extent these pathways contribute to functional activation of p53 in response to oxidizing conditions. Collectively, our data suggest that p53 can be activated both by SAPK signaling and the DDR independently of each other, and which of these pathways is activated depends on the type of oxidant used. This implies that it could in principle be possible to modulate oxidative signaling to stimulate p53 without inducing collateral DNA damage, thereby limiting mutation accumulation in both healthy and tumor tissues.
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Affiliation(s)
- Tao Shi
- Center for Molecular Medicine, Molecular Cancer Research, the Netherlands
| | - Daan M K van Soest
- Center for Molecular Medicine, Molecular Cancer Research, the Netherlands
| | | | - Boudewijn M T Burgering
- Center for Molecular Medicine, Molecular Cancer Research, the Netherlands; Oncode Institute, University Medical Center Utrecht, Universiteitsweg, 100 3584, CG, Utrecht, the Netherlands
| | - Tobias B Dansen
- Center for Molecular Medicine, Molecular Cancer Research, the Netherlands.
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7
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Singh R, Kaur N, Dhingra N, Kaur T. Protein misfolding, ER Stress and Chaperones: An approach to develop chaperone-based therapeutics for Alzheimer's Disease. Int J Neurosci 2021:1-21. [PMID: 34402740 DOI: 10.1080/00207454.2021.1968859] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Alzheimer's disease (AD) is a heterogeneous neurodegenerative disorder with complex etiology that eventually leads to dementia. The main culprit of AD is the extracellular deposition of β-amyloid (Aβ) and intracellular neurofibrillary tangles. The protein conformational change and protein misfolding are the key events of AD pathophysiology, therefore endoplasmic reticulum (ER) stress is an apparent consequence. ER, stress-induced unfolded protein response (UPR) mediators (viz. PERK, IRE1, and ATF6) have been reported widely in the AD brain. Considering these factors, preventing proteins misfolding or aggregation of tau or amyloidogenic proteins appears to be the best approach to halt its pathogenesis. Therefore, therapies through chemical and pharmacological chaperones came to light as an alternative for the treatment of AD. Diverse studies have demonstrated 4-phenylbutyric acid (4-PBA) as a potential therapeutic agent in AD. The current review outlined the mechanism of protein misfolding, different etiological features behind the progression of AD, the significance of ER stress in AD, and the potential therapeutic role of different chaperones to counter AD. The study also highlights the gaps in current knowledge of the chaperones-based therapeutic approach and the possibility of developing chaperones as a potential therapeutic agent for AD treatment.
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Affiliation(s)
- Rimaljot Singh
- Department of Biophysics, Panjab University Chandigarh, India
| | - Navpreet Kaur
- Department of Biophysics, Panjab University Chandigarh, India
| | - Neelima Dhingra
- University Institute of Pharmaceutical Sciences, Panjab University Chandigarh, India
| | - Tanzeer Kaur
- Department of Biophysics, Panjab University Chandigarh, India
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8
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Grape pomace inhibits colon carcinogenesis by suppressing cell proliferation and inducing epigenetic modifications. J Nutr Biochem 2020; 84:108443. [PMID: 32629240 DOI: 10.1016/j.jnutbio.2020.108443] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/23/2020] [Accepted: 05/27/2020] [Indexed: 12/18/2022]
Abstract
Grape pomace (GP), a by-product of the wine and juice industry, is rich in bioflavonoids and dietary fibers. We hypothesized that GP has protective effects against colitis-associated colorectal cancer (CRC). Nine-week-old female mice were fed a control diet (CON) or CON with 5% grape pomace (GP) for 2 weeks, when mice were subjected to azoxymethane (AOM)/dextran sulfate sodium (DSS) induced-CRC induction. GP supplementation ameliorated the disease activity index (DAI) score, reduced tumor number, tumor size and pathological scores in AOM/DSS treated mice. Furthermore, dietary GP suppressed colonic expression of inflammatory cytokines, IL-1β and TNF-α, and inhibited NF-κB inflammatory signaling, while increased anti-inflammatory cytokine TGF-β mRNA expression. Colorectal inflammation is known to enhance Wnt signaling and cell proliferation. In agreement, the content of β-catenin, a key downstream mediator of Wnt signaling, was reduced as was the expression of Cyclin D1, phosphorylation and content of p53 and PCNA level in GP-fed mice. In addition, GP reduced the expression of ALDH1, a marker of cell stemness, and increased the expression of Cdx2, a key transcription factor initiating epithelial cell differentiation, DNA methylation of the promoter region of Cdx2 gene and hypermethylation of CpG island methylator phenotype (CIMP), which commonly occurs during CRC carcinogenesis, was alleviated in the GP group. In conclusion, GP supplementation suppressed colitis-associated CRC carcinogenesis, which was associated with the suppression of inflammation and cell proliferation and the enhancement of DNA demethylation in Cdx2 and CIMP genes in the colon. These data suggest that dietary GP supplementation has preventive effects against colorectal carcinogenesis.
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Anwar A, Anwar H, Yamauchi T, Tseng R, Agarwal R, Horwitz LD, Zhai Z, Fujita M. Bucillamine Inhibits UVB-Induced MAPK Activation and Apoptosis in Human HaCaT Keratinocytes and SKH-1 Hairless Mouse Skin. Photochem Photobiol 2020; 96:870-876. [PMID: 32077107 DOI: 10.1111/php.13228] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 12/17/2019] [Indexed: 12/12/2022]
Abstract
Ultraviolet B (UVB) radiation is known as a culprit in skin carcinogenesis. We have previously reported that bucillamine (N-[2-mercapto-2-methylpropionyl]-L-cysteine), a cysteine derivative with antioxidant and anti-inflammatory capacity, protects against UVB-induced p53 activation and inflammatory responses in mouse skin. Since MAPK signaling pathways regulate p53 expression and activation, here we determined bucillamine effect on UVB-mediated MAPK activation in vitro using human skin keratinocyte cell line HaCaT and in vivo using SKH-1 hairless mouse skin. A single low dose of UVB (30 mJ cm-2 ) resulted in increased JNK/MAPK phosphorylation and caspase-3 cleavage in HaCaT cells. However, JNK activation and casaspe-3 cleavage were inhibited by pretreatment of HaCaT cells with physiological doses of bucillamine (25 and 100 µm). Consistent with these results, bucillamine pretreatment in mice (20 mg kg-1 ) inhibited JNK/MAPK and ERK/MAPK activation in skin epidermal cells at 6-12 and 24 h, respectively, after UVB exposure. Moreover, bucillamine attenuated UVB-induced Ki-67-positive cells and cleaved caspase-3-positive cells in mouse skin. These findings demonstrate that bucillamine inhibits UVB-induced MAPK signaling, cell proliferation and apoptosis. Together with our previous report, we provide evidence that bucillamine has a photoprotective effect against UV exposure.
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Affiliation(s)
- Adil Anwar
- Department of Dermatology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Hiba Anwar
- Department of Dermatology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Takeshi Yamauchi
- Department of Dermatology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Ryan Tseng
- Department of Dermatology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Rajesh Agarwal
- Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Lawrence D Horwitz
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Zili Zhai
- Department of Dermatology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Mayumi Fujita
- Department of Dermatology, University of Colorado Anschutz Medical Campus, Aurora, CO.,Denver Veterans Affairs Medical Center, Denver, CO
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10
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Cui J, Wang J, Huang S, Jiang X, Li Y, Wu W, Zhang X. The G2 phase arrest induced by sterigmatocystin is dependent on hMLH1- ERK/p38-p53 pathway in human esophageal epithelium cells in vitro. Food Chem Toxicol 2018; 115:205-211. [DOI: 10.1016/j.fct.2018.03.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 03/06/2018] [Accepted: 03/09/2018] [Indexed: 01/12/2023]
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11
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Ruiz R, Jahid S, Harris M, Marzese DM, Espitia F, Vasudeva P, Chen CF, de Feraudy S, Wu J, Gillen DL, Krasieva TB, Tromberg BJ, Pavan WJ, Hoon DS, Ganesan AK. The RhoJ-BAD signaling network: An Achilles' heel for BRAF mutant melanomas. PLoS Genet 2017; 13:e1006913. [PMID: 28753606 PMCID: PMC5549996 DOI: 10.1371/journal.pgen.1006913] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 08/09/2017] [Accepted: 07/06/2017] [Indexed: 12/15/2022] Open
Abstract
Genes and pathways that allow cells to cope with oncogene-induced stress represent selective cancer therapeutic targets that remain largely undiscovered. In this study, we identify a RhoJ signaling pathway that is a selective therapeutic target for BRAF mutant cells. RhoJ deletion in BRAF mutant melanocytes modulates the expression of the pro-apoptotic protein BAD as well as genes involved in cellular metabolism, impairing nevus formation, cellular transformation, and metastasis. Short-term treatment of nascent melanoma tumors with PAK inhibitors that block RhoJ signaling halts the growth of BRAF mutant melanoma tumors in vivo and induces apoptosis in melanoma cells in vitro via a BAD-dependent mechanism. As up to 50% of BRAF mutant human melanomas express high levels of RhoJ, these studies nominate the RhoJ-BAD signaling network as a therapeutic vulnerability for fledgling BRAF mutant human tumors. BRAFV600E is the most common mutation in human melanomas, and kinase inhibitors that block BRAFV600E signaling can rapidly induce tumor regression but only modestly improve melanoma long-term survival. In this study, we identify a novel therapeutic vulnerability for BRAF mutant melanoma tumors. Targeting RhoJ signaling with existing PAK inhibitors was more efficient at blocking the progression of BRAF mutant tumors in vivo when compared to kinase inhibitors currently used to treat melanoma. Approximately half of all human BRAF mutant melanoma tumors express high levels of RhoJ, identifying the RhoJ-BAD pathway as a novel target for melanoma.
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Affiliation(s)
- Rolando Ruiz
- Department of Biological Chemistry, University of California, Irvine, Irvine, CA, United States of America
| | - Sohail Jahid
- Department of Dermatology, University of California, Irvine, Irvine, CA, United States of America
| | - Melissa Harris
- Department of Biology, The University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Diego M. Marzese
- Department of Translational Molecular Medicine, Division Molecular Oncology, John Wayne Cancer Institute (JWCI), Providence Saint John's Health Center, Santa Monica, CA, United States of America
| | - Francisco Espitia
- Department of Dermatology, University of California, Irvine, Irvine, CA, United States of America
| | - Priya Vasudeva
- Department of Dermatology, University of California, Irvine, Irvine, CA, United States of America
| | - Chi-Fen Chen
- Department of Dermatology, University of California, Irvine, Irvine, CA, United States of America
| | - Sebastien de Feraudy
- Department of Dermatology, University of California, Irvine, Irvine, CA, United States of America
| | - Jie Wu
- Department of Biological Chemistry, University of California, Irvine, Irvine, CA, United States of America
| | - Daniel L. Gillen
- Department of Statistics, University of California, Irvine, Irvine, CA, United States of America
| | - Tatiana B. Krasieva
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, Irvine, CA, United States of America
| | - Bruce J. Tromberg
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, Irvine, CA, United States of America
| | - William J. Pavan
- National Human Genome Research Institute, National Institute of Health, Bethesda, MD, United States of America
| | - Dave S. Hoon
- Department of Translational Molecular Medicine, Division Molecular Oncology, John Wayne Cancer Institute (JWCI), Providence Saint John's Health Center, Santa Monica, CA, United States of America
| | - Anand K. Ganesan
- Department of Biological Chemistry, University of California, Irvine, Irvine, CA, United States of America
- Department of Dermatology, University of California, Irvine, Irvine, CA, United States of America
- * E-mail:
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12
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Sreekanth GP, Chuncharunee A, Cheunsuchon B, Noisakran S, Yenchitsomanus PT, Limjindaporn T. JNK1/2 inhibitor reduces dengue virus-induced liver injury. Antiviral Res 2017; 141:7-18. [PMID: 28188818 DOI: 10.1016/j.antiviral.2017.02.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/26/2017] [Accepted: 02/05/2017] [Indexed: 11/20/2022]
Abstract
High viral load with liver injury is exhibited in severe dengue virus (DENV) infection. Mitogen activated protein kinases (MAPKs) including ERK1/2 and p38 MAPK were previously found to be involved in the animal models of DENV-induced liver injury. However, the role of JNK1/2 signaling in DENV-induced liver injury has never been investigated. JNK1/2 inhibitor, SP600125, was used to investigate the role of JNK1/2 signaling in the BALB/c mouse model of DENV-induced liver injury. SP600125-treated DENV-infected mice ameliorated leucopenia, thrombocytopenia, hemoconcentration, liver transaminases and liver histopathology. DENV-induced liver injury exhibited induced phosphorylation of JNK1/2, whereas SP600125 reduced this phosphorylation. An apoptotic real-time PCR array profiler was used to screen how SP600125 affects the expression of 84 cell death-associated genes to minimize DENV-induced liver injury. Modulation of caspase-3, caspase-8 and caspase-9 expressions by SP600125 in DENV-infected mice suggests its efficiency in restricting apoptosis via both extrinsic and intrinsic pathways. Reduced expressions of TNF-α and TRAIL are suggestive to modulate the extrinsic apoptotic signals, where reduced p53 phosphorylation and induced anti-apoptotic Bcl-2 expression indicate the involvement of the intrinsic apoptotic pathway. This study thus demonstrates the pivotal role of JNK1/2 signaling in DENV-induced liver injury and how SP600125 modulates this pathogenesis.
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Affiliation(s)
- Gopinathan Pillai Sreekanth
- Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Division of Molecular Medicine, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Aporn Chuncharunee
- Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Boonyarit Cheunsuchon
- Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Sansanee Noisakran
- Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok, Thailand
| | - Pa-Thai Yenchitsomanus
- Division of Molecular Medicine, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Thawornchai Limjindaporn
- Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Division of Molecular Medicine, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
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13
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Ben-Ami Shor D, Blank M, Reuter S, Matthias T, Beiglass I, Volkov A, Barshack I, Shoenfeld Y. Anti-ribosomal-P antibodies accelerate lupus glomerulonephritis and induce lupus nephritis in naïve mice. J Autoimmun 2014; 54:118-26. [DOI: 10.1016/j.jaut.2014.02.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 02/18/2014] [Accepted: 02/26/2014] [Indexed: 11/24/2022]
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14
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Calvo N, Martín MJ, de Boland AR, Gentili C. Involvement of ERK1/2, p38 MAPK, and PI3K/Akt signaling pathways in the regulation of cell cycle progression by PTHrP in colon adenocarcinoma cells. Biochem Cell Biol 2014; 92:305-15. [DOI: 10.1139/bcb-2013-0106] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Parathyroid hormone-related peptide (PTHrP) is distributed in most fetal and adult tissues, and its expression correlates with the severity of colon carcinoma. Recently we obtained evidence that in Caco-2 cells, a cell line from human colorectal adenocarcinoma, exogenous PTHrP increases the number of live cells, via ERK1/2, p38 MAPK, and PI3-kinase and induces the expression of cyclin D1, a cell cycle regulatory protein. In this study, we further investigated the role of PTHrP in the regulation of the cell cycle progression in these intestinal cells. Flow cytometry analysis revealed that PTHrP treatment diminishes the number of cells in the G0/G1 phase and increases the number in both S and G2/M phases. The hormone increases the expression of CDK6 and diminishes the amount of negative cell cycle regulators p27Kip1, p15INK4B, and p53. However, PTHrP does not modify the expression of cyclin D3, CDK4, and p16INK4A. In addition, inhibitors of ERK1/2 (PD98059), p38 MAPK (SB203580), and PI3Kinase (LY294002) reversed PTHrP response in Caco-2 cells. Taken together, our results suggest that PTHrP positively modulates cell cycle progression and changes the expression of proteins involved in cell cycle regulation via ERK1/2, p38 MAPK, and PI3K signaling pathways in Caco-2 cells.
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Affiliation(s)
- Natalia Calvo
- Dept. Biología, Bioquímica y Farmacia. Universidad Nacional del Sur, San Juan 670, (8000) Bahía Blanca, Argentina
| | - María Julia Martín
- Dept. Biología, Bioquímica y Farmacia. Universidad Nacional del Sur, San Juan 670, (8000) Bahía Blanca, Argentina
| | - Ana Russo de Boland
- Dept. Biología, Bioquímica y Farmacia. Universidad Nacional del Sur, San Juan 670, (8000) Bahía Blanca, Argentina
| | - Claudia Gentili
- Dept. Biología, Bioquímica y Farmacia. Universidad Nacional del Sur, San Juan 670, (8000) Bahía Blanca, Argentina
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15
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Pietkiewicz S, Sohn D, Piekorz RP, Grether-Beck S, Budach W, Sabapathy K, Jänicke RU. Oppositional regulation of Noxa by JNK1 and JNK2 during apoptosis induced by proteasomal inhibitors. PLoS One 2013; 8:e61438. [PMID: 23593480 PMCID: PMC3623862 DOI: 10.1371/journal.pone.0061438] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 03/14/2013] [Indexed: 01/28/2023] Open
Abstract
Proteasome inhibitors (PIs) potently induce apoptosis in a variety of tumor cells, but the underlying mechanisms are not fully elucidated. Comparing PI-induced apoptosis susceptibilities of various mouse embryonic fibroblast (MEF) lines differing in their c-jun N-terminal kinase (JNK) 1 and 2 status, we show that several hallmarks of apoptosis were most rapidly detectable in JNK2-/- cells, whereas they appeared only delayed and severely reduced in their intensities in cells expressing JNK2. Consistent with our finding that PI-induced apoptosis requires de novo protein synthesis, the proteasomal inhibitor MG-132 induced expression of the BH3-only protein Noxa at the transcriptional level in a JNK1-dependent, but JNK2-opposing manner. As the knockdown of Noxa blocked only the rapid PI-induced apoptosis of JNK2-/- cells, but not the delayed death occurring in JNK1-/- and JNK1+/+ cells, our data uncover a novel PI-induced apoptosis pathway that is regulated by the JNK1/2-dependent expression of Noxa. Furthermore, several transcription factors known to modulate Noxa expression including ATF3, ATF4, c-Jun, c-Myc, HIF1α, and p53 were found upregulated following MG-132 exposure. From those, only knockdown of c-Myc rescued JNK2-/- cells from PI-induced apoptosis, however, without affecting expression of Noxa. Together, our data not only show that a rapid execution of PI-induced apoptosis requires JNK1 for upregulation of Noxa via an as yet unknown transcription factor, but also that JNK2 controls this event in an oppositional manner.
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Affiliation(s)
- Sabine Pietkiewicz
- Laboratory of Molecular Radiooncology, Clinic and Policlinic for Radiation Therapy and Radiooncology, University of Düsseldorf, Düsseldorf, Germany
| | - Dennis Sohn
- Laboratory of Molecular Radiooncology, Clinic and Policlinic for Radiation Therapy and Radiooncology, University of Düsseldorf, Düsseldorf, Germany
| | - Roland P. Piekorz
- Institute for Biochemistry and Molecular Biology II, University of Düsseldorf, Düsseldorf, Germany
| | | | - Wilfried Budach
- Laboratory of Molecular Radiooncology, Clinic and Policlinic for Radiation Therapy and Radiooncology, University of Düsseldorf, Düsseldorf, Germany
| | - Kanaga Sabapathy
- Division of Cellular & Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore
| | - Reiner U. Jänicke
- Laboratory of Molecular Radiooncology, Clinic and Policlinic for Radiation Therapy and Radiooncology, University of Düsseldorf, Düsseldorf, Germany
- * E-mail:
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Regulation of human lung alveolar multipotent cells by a novel p38α MAPK/miR-17-92 axis. EMBO J 2012; 31:3431-41. [PMID: 22828869 PMCID: PMC3419929 DOI: 10.1038/emboj.2012.192] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Accepted: 06/22/2012] [Indexed: 12/30/2022] Open
Abstract
This study characterizes putative human lung stem cells based on E-cadherin/Lgr6 expression. Long-term clonal expansion, the ability to form bronchioalveolar-like epithelia and the discovery of the miR-17-92 cluster as regulator of their proliferative capacity are features of this unique stem cell population. The cellular and molecular mechanisms that control lung homeostasis and regeneration are still poorly understood. It has been proposed that a population of cells exists in the mouse lung with the potential to differentiate into all major lung bronchioalveolar epithelium cell types in homeostasis or in response to virus infection. A new population of E-Cad/Lgr6+ putative stem cells has been isolated, and indefinitely expanded from human lungs, harbouring both, self-renewal capacity and the potency to differentiate in vitro and in vivo. Recently, a putative population of human lung stem cells has been proposed as being c-Kit+. Unlike Integrin-α6+ or c-Kit+ cells, E-Cad/Lgr6+ single-cell injections in the kidney capsule produce differentiated bronchioalveolar tissue, while retaining self-renewal, as they can undergo serial transplantations under the kidney capsule or in the lung. In addition, a signalling network involving the p38α pathway, the activation of p53 and the regulation of the miR-17-92 cluster has been identified. Disruption of the proper cross-regulation of this signalling axis might be involved in the promotion of human lung diseases.
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Viana RJS, Nunes AF, Rodrigues CMP. Endoplasmic reticulum enrollment in Alzheimer's disease. Mol Neurobiol 2012; 46:522-34. [PMID: 22815194 DOI: 10.1007/s12035-012-8301-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 07/05/2012] [Indexed: 12/26/2022]
Abstract
Alzheimer's disease (AD) poses a huge challenge for society and health care worldwide as molecular pathogenesis of the disease is poorly understood and curative treatment does not exist. The mechanisms leading to accelerated neuronal cell death in AD are still largely unknown, but accumulation of misfolded disease-specific proteins has been identified as potentially involved. In the present review, we describe the essential role of endoplasmic reticulum (ER) in AD. Despite the function that mitochondria may play as the central major player in the apoptotic process, accumulating evidence highlights ER as a critical organelle in AD. Stress that impairs ER physiology leads to accumulation of unfolded or misfolded proteins, such as amyloid β (Aβ) peptide, the major component of amyloid plaques. In an attempt to ameliorate the accumulation of unfolded proteins, ER stress triggers a protective cellular mechanism, which includes the unfolded protein response (UPR). However, when activation of the UPR is severe or prolonged enough, the final cellular outcome is pathologic apoptotic cell death. Distinct pathways can be activated in this process, involving stress sensors such as the JNK pathway or ER chaperones such as Bip/GRP94, stress modulators such as Bcl-2 family proteins, or even stress effectors such as caspase-12. Here, we detail the involvement of the ER and associated stress pathways in AD and discuss potential therapeutic strategies targeting ER stress.
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Affiliation(s)
- Ricardo J S Viana
- Research Institute for Medicines and Pharmaceutical Sciences, University of Lisbon, Lisbon 1649-003, Portugal
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Hawkes WC, Alkan Z. Delayed cell cycle progression in selenoprotein W-depleted cells is regulated by a mitogen-activated protein kinase kinase 4-p38/c-Jun NH2-terminal kinase-p53 pathway. J Biol Chem 2012; 287:27371-9. [PMID: 22730327 DOI: 10.1074/jbc.m112.346593] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Selenoprotein W (SEPW1) is a ubiquitous, highly conserved thioredoxin-like protein whose depletion causes a transient p53- and p21(Cip1)-dependent G(1)-phase cell cycle arrest in breast and prostate epithelial cells. SEPW1 depletion increases phosphorylation of Ser-33 in p53, which is associated with decreased p53 ubiquitination and stabilization of p53. We report here that delayed cell cycle progression, Ser-33 phosphorylation, and p53 nuclear accumulation from SEPW1 depletion require mitogen-activated protein kinase kinase 4 (MKK4). Silencing MKK4 rescued G(1) arrest, Ser-33 phosphorylation, and nuclear accumulation of p53 induced by SEPW1 depletion, but silencing MKK3, MKK6, or MKK7 did not. SEPW1 silencing did not change the phosphorylation state of MKK4 but increased total MKK4 protein. Silencing p38γ, p38δ, or JNK2 partially rescued G(1) arrest from SEPW1 silencing, suggesting they signal downstream from MKK4. These results imply that SEPW1 silencing increases MKK4, which activates p38γ, p38δ, and JNK2 to phosphorylate p53 on Ser-33 and cause a transient G(1) arrest.
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Affiliation(s)
- Wayne Chris Hawkes
- Western Human Nutrition Research Center, United States Department of Agriculture, Agricultural Research Service, University of California, Davis, California 95616, USA.
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Targeting p53 via JNK pathway: a novel role of RITA for apoptotic signaling in multiple myeloma. PLoS One 2012; 7:e30215. [PMID: 22276160 PMCID: PMC3262803 DOI: 10.1371/journal.pone.0030215] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2011] [Accepted: 12/12/2011] [Indexed: 12/21/2022] Open
Abstract
The low frequency of p53 alterations e.g., mutations/deletions (∼10%) in multiple myeloma (MM) makes this tumor type an ideal candidate for p53-targeted therapies. RITA is a small molecule which can induce apoptosis in tumor cells by activating the p53 pathway. We previously showed that RITA strongly activates p53 while selectively inhibiting growth of MM cells without inducing genotoxicity, indicating its potential as a drug lead for p53-targeted therapy in MM. However, the molecular mechanisms underlying the pro-apoptotic effect of RITA are largely undefined. Gene expression analysis by microarray identified a significant number of differentially expressed genes associated with stress response including c-Jun N-terminal kinase (JNK) signaling pathway. By Western blot analysis we further confirmed that RITA induced activation of p53 in conjunction with up-regulation of phosphorylated ASK-1, MKK-4 and c-Jun. These results suggest that RITA induced the activation of JNK signaling. Chromatin immunoprecipitation (ChIP) analysis showed that activated c-Jun binds to the activator protein-1 (AP-1) binding site of the p53 promoter region. Disruption of the JNK signal pathway by small interfering RNA (siRNA) against JNK or JNK specific inhibitor, SP-600125 inhibited the activation of p53 and attenuated apoptosis induced by RITA in myeloma cells carrying wild type p53. On the other hand, p53 transcriptional inhibitor, PFT-α or p53 siRNA not only inhibited the activation of p53 transcriptional targets but also blocked the activation of c-Jun suggesting the presence of a positive feedback loop between p53 and JNK. In addition, RITA in combination with dexamethasone, known as a JNK activator, displays synergistic cytotoxic responses in MM cell lines and patient samples. Our study unveils a previously undescribed mechanism of RITA-induced p53-mediated apoptosis through JNK signaling pathway and provides the rationale for combination of p53 activating drugs with JNK activators in the treatment of MM.
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20
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MAPKs activation in head and neck squamous cell carcinomas. Oncol Rev 2011. [DOI: 10.1007/s12156-011-0086-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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21
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Papazoglou E, Huang ZY, Sunkari C, Uitto J. The role of Syk kinase in ultraviolet-mediated skin damage. Br J Dermatol 2011; 165:69-77. [PMID: 21410673 DOI: 10.1111/j.1365-2133.2011.10309.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Ultraviolet (UV) irradiation is the main cause of skin photodamage; the resulting modulation of matrix metalloproteinases (MMPs) leads to collagen degradation. There is no easily accessible molecular indicator of early skin UV damage. OBJECTIVES In this study, we investigated the effects of Syk kinase on MMP expression and evaluated the sensitivity and usefulness of Syk as an early indicator of skin UV damage. METHODS Human dermal fibroblasts (HDFs) were transfected with Syk cDNA to overexpress Syk. MMP-1 expression and Syk activity were determined by Western blot after UV exposure. The effect of Syk on MMP-1 expression in HDFs was further explored by either Syk siRNA or a selective Syk inhibitor. Possible downstream molecules of Syk were also evaluated in HDFs upon UV exposure. The relationship between Syk and collagenase was further explored in vivo (MMP-13, hairless mice). RESULTS Our studies in HDFs demonstrated that both a Syk inhibitor and Syk siRNA were able to inhibit MMP-1 expression in HDFs exposed to UV and that overexpression of Syk increased MMP-1 expression and the activity of JNK kinase, but not p38 or Erk1/2 MAP kinase. UV exposure enhanced both expression and activity of Syk in HDFs. Experiments with hairless mice suggested that Syk expression is an earlier indicator of UV exposure than MMP-13 expression. CONCLUSIONS Our results demonstrate that Syk expression correlates well with increase of MMPs (MMP-1 in humans and MMP-13 in mice) in response to UV exposure. The findings suggest that Syk may be a novel target for the prevention and treatment of skin photodamage by modulating MMPs.
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Affiliation(s)
- E Papazoglou
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19104, USA.
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22
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Venerando A, Marin O, Cozza G, Bustos VH, Sarno S, Pinna LA. Isoform specific phosphorylation of p53 by protein kinase CK1. Cell Mol Life Sci 2010; 67:1105-18. [PMID: 20041275 PMCID: PMC11115815 DOI: 10.1007/s00018-009-0236-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 11/18/2009] [Accepted: 12/14/2009] [Indexed: 12/27/2022]
Abstract
The ability of three isoforms of protein kinase CK1 (alpha, gamma(1), and delta) to phosphorylate the N-terminal region of p53 has been assessed using either recombinant p53 or a synthetic peptide reproducing its 1-28 sequence. Both substrates are readily phosphoylated by CK1delta and CK1alpha, but not by the gamma isoform. Affinity of full size p53 for CK1 is 3 orders of magnitude higher than that of its N-terminal peptide (K (m) 0.82 muM vs 1.51 mM). The preferred target is S20, whose phosphorylation critically relies on E17, while S6 is unaffected despite displaying the same consensus (E-x-x-S). Our data support the concept that non-primed phosphorylation of p53 by CK1 is an isoform-specific reaction preferentially affecting S20 by a mechanism which is grounded both on a local consensus and on a remote docking site mapped to the K(221)RQK(224) loop according to modeling and mutational analysis.
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Affiliation(s)
- Andrea Venerando
- Venetian Institute of Molecular Medicine (VIMM), Via G. Orus, 2, 35129 Padova, Italy
- Department of Biological Chemistry, University of Padova, Viale G. Colombo, 3, 35131 Padova, Italy
| | - Oriano Marin
- Venetian Institute of Molecular Medicine (VIMM), Via G. Orus, 2, 35129 Padova, Italy
- Department of Biological Chemistry, University of Padova, Viale G. Colombo, 3, 35131 Padova, Italy
| | - Giorgio Cozza
- Department of Biological Chemistry, University of Padova, Viale G. Colombo, 3, 35131 Padova, Italy
| | - Victor H. Bustos
- Venetian Institute of Molecular Medicine (VIMM), Via G. Orus, 2, 35129 Padova, Italy
- Present Address: Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, NY 10065 USA
| | - Stefania Sarno
- Venetian Institute of Molecular Medicine (VIMM), Via G. Orus, 2, 35129 Padova, Italy
- Department of Biological Chemistry, University of Padova, Viale G. Colombo, 3, 35131 Padova, Italy
| | - Lorenzo Alberto Pinna
- Venetian Institute of Molecular Medicine (VIMM), Via G. Orus, 2, 35129 Padova, Italy
- Department of Biological Chemistry, University of Padova, Viale G. Colombo, 3, 35131 Padova, Italy
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Abstract
The p53 protein is one of the most important tumor suppressor proteins. Normally, the p53 protein is in a latent state. However, when its activity is required, e.g. upon DNA damage, nucleotide depletion or hypoxia, p53 becomes rapidly activated and initiates transcription of pro-apoptotic and cell cycle arrest-inducing target genes. The activity of p53 is regulated both by protein abundance and by post-translational modifications of pre-existing p53 molecules. In the 30 years of p53 research, a plethora of modifications and interaction partners that modulate p53's abundance and activity have been identified and new ones are continuously discovered. This review will summarize our current knowledge on the regulation of p53 abundance and activity.
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Affiliation(s)
- Karen A Boehme
- Forschungszentrum Karlsruhe, Institute of Toxicology and Genetics, Karlsruhe, Germany
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24
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Antitumor activity of TMPyP4 interacting G-quadruplex in retinoblastoma cell lines. Exp Eye Res 2009; 89:200-8. [PMID: 19328784 DOI: 10.1016/j.exer.2009.03.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 03/11/2009] [Accepted: 03/18/2009] [Indexed: 11/22/2022]
Abstract
To investigate the molecular mechanism of the antitumor activity of the cationic porphyrin 5, 10, 15, 20-tetra-(N-methyl-4-pyridyl)porphyrin (TMPyP4) in retinoblastoma cell lines, Y79 and WERI-Rb1 cells were treated with TMPyP4 for 0-72 h, after which growth inhibition, modulation of the cell cycle and the induction of apoptosis were examined. In addition, the effect of TMPyP4 on the susceptibility to irradiation was evaluated in Y79 and WERI-Rb1 cells. In vitro telomeric repeat amplification protocol assay showed TMPyP4 (10-100 microM) directly blocked telomerase elongation, suggesting that TMPyP4 can form stable guanine (G)-quadruplexes in extending telomere repeats in substrate oligonucleotides. The antiproliferative activities of TMPyP4 assessed with the MTS assay and expressed in terms of IC(50): Y79 cells, 60 microM; WERI-Rb1 cells, 45 microM. Treatment with TMPyP4 at doses of 10, 20, 50 or 100 microM for 48 or 72 h significantly inhibited the growth of Y79 and WERI-Rb1 cells. Apoptosis, as assessed with CaspACE FITC-VAD-FMK, was induced by TMPyP4 in a dose-dependent manner. Induction of apoptosis by TMPyP4 was associated with increased expression of phosphorylated DNA damage response factor H2AX (Ser139), phosphorylated p53 (Ser46) protein and activation of mitogen-activated protein kinases in Y79 and WERI-Rb1 cells. Moreover, TMPyP4 significantly enhanced the susceptibility to irradiation in both cell lines. This study provides insight into the molecular mechanism of the antitumor effects of TMPyP4. G-quadruplex structure may be a potential therapeutic target in retinoblastoma.
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25
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Modulation of p53 by mitogen-activated protein kinase pathways and protein kinase C δ during avian reovirus S1133-induced apoptosis. Virology 2009; 385:323-34. [DOI: 10.1016/j.virol.2008.12.028] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 12/12/2008] [Accepted: 12/17/2008] [Indexed: 01/08/2023]
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How DNA lesions are turned into powerful killing structures: insights from UV-induced apoptosis. Mutat Res 2008; 681:197-208. [PMID: 18845270 DOI: 10.1016/j.mrrev.2008.09.001] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 09/08/2008] [Accepted: 09/09/2008] [Indexed: 11/22/2022]
Abstract
Mammalian cells treated with ultraviolet (UV) light provide one of the best-known experimental systems for depicting the biological consequences of DNA damage. UV irradiation induces the formation of DNA photoproducts, mainly cyclobutane pyrimidine dimers (CPDs) and (6-4) pyrimidine-pyrimidone photoproducts [(6-4)PPs], that drastically impairs DNA metabolism, culminating in the induction of cell death by apoptosis. While CPDs are the most important apoptosis-inducing lesions in DNA repair proficient cells, recent data indicates that (6-4)PPs also signals for apoptosis in DNA repair deficient cells. The toxic effects of these unrepaired DNA lesions are commonly associated with transcription blockage, but there is increasing evidence supporting a role for replication blockage as an apoptosis-inducing signal. This is supported by the observations that DNA double-strand breaks (DSBs) arise at the sites of stalled replication forks, that these DSBs are potent inducers of apoptosis and that inhibition of S phase progression diminishes the apoptotic response. Reactive oxygen species, generated after exposure of mammalian cells to longer UV wavelengths, may also induce apoptotic responses. In this regard, emphasis is given to the formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-OxoG), but indirect induced lesions such as lipoperoxide DNA adducts also deserve attention. ATR is the main established sensor molecule for UV-induced DNA damage. However, there is evidence that ATM as well as the MAPK pathway also play a role in the UV response by activating either the death receptor or the mitochondrial damage pathway. Adding more complexity to the subject, cells under stress suffer other types of processes that may result in cell death. Autophagy is one of these processes, with extensive cross-talks with apoptosis. No matter the mechanisms, cell death avoids cells to perpetuate mutations induced by genotoxic lesions. The understanding of such death responses may provide the means for the development of strategies for the prevention and treatment of cancer.
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Scicchitano MS, McFarland DC, Tierney LA, Boyce RW, Frazier KS, Schwartz LW, Thomas HC. Role of p38 in regulation of hematopoiesis: Effect of p38 inhibition on cytokine production and transcription factor activity in human bone marrow stromal cells. Blood Cells Mol Dis 2008; 40:370-80. [DOI: 10.1016/j.bcmd.2007.10.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Accepted: 10/30/2007] [Indexed: 10/22/2022]
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28
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Lin T, Mak N, Yang M. MAPK regulate p53-dependent cell death induced by benzo[a]pyrene: Involvement of p53 phosphorylation and acetylation. Toxicology 2008; 247:145-53. [DOI: 10.1016/j.tox.2008.02.017] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Revised: 02/26/2008] [Accepted: 02/26/2008] [Indexed: 11/17/2022]
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29
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Einspahr JG, Timothy Bowden G, Alberts DS, McKenzie N, Saboda K, Warneke J, Salasche S, Ranger-Moore J, Curiel-Lewandrowski C, Nagle RB, Nickoloff BJ, Brooks C, Dong Z, Stratton SP. Cross-validation of Murine UV Signal Transduction Pathways in Human Skin. Photochem Photobiol 2008; 84:463-76. [DOI: 10.1111/j.1751-1097.2007.00287.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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30
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Rouget R, Auclair Y, Loignon M, Affar EB, Drobetsky EA. A sensitive flow cytometry-based nucleotide excision repair assay unexpectedly reveals that mitogen-activated protein kinase signaling does not regulate the removal of UV-induced DNA damage in human cells. J Biol Chem 2007; 283:5533-41. [PMID: 18093981 DOI: 10.1074/jbc.m706257200] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
In response to diverse genotoxic stimuli (e.g. UV and cisplatin), the mitogen-activated protein kinases ERK1/2, JNK1/2, and p38alpha/beta become rapidly phosphorylated and in turn activate multiple downstream effectors that modulate apoptosis and/or growth arrest. Furthermore, previous lines of evidence have strongly suggested that ERK1/2 and JNK1/2 participate in global-genomic nucleotide excision repair, a critical antineoplastic pathway that removes helix-distorting DNA adducts induced by a variety of mutagenic agents, including UV. To rigorously evaluate the potential role of mitogen-activated protein kinases in global-genomic nucleotide excision repair, various human cell strains (primary skin fibroblasts, primary lung fibroblasts, and HCT116 colon carcinoma cells) were treated with highly specific chemical inhibitors, which, following UV exposure, (i) abrogated the capacities of ERK1/2, JNK1/2, or p38alpha/beta to phosphorylate specific downstream effectors and (ii) characteristically modulated cellular proliferation, clonogenic survival, and/or apoptosis. A highly sensitive flow cytometry-based nucleotide excision repair assay recently optimized and validated in our laboratory was then employed to directly demonstrate that the kinetics of UV DNA photoadduct repair are highly similar in mock-treated versus mitogen-activated protein kinase inhibitor-treated cells. These data on primary and tumor cells treated with pharmacological inhibitors were fully corroborated by repair studies using (i) short hairpin RNA-mediated knockdown of ERK1/2 or JNK1/2 in human U2OS osteosarcoma cells and (ii) expression of a dominant negative p38alpha mutant in human primary lung fibroblasts. Our results provide solid evidence for the first time, in disaccord with a burgeoning perception, that mitogen-activated protein kinase signaling does not influence the efficiency of human global-genomic nucleotide excision repair.
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Affiliation(s)
- Raphael Rouget
- Department of Immunology/Oncology, Maisonneuve-Rosemont Hospital Research Center, Faculty of Medicine, University of Montreal, Montreal, Quebec H1T 2M4, Canada
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31
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Teng CH, Huang WN, Meng TC. Several dual specificity phosphatases coordinate to control the magnitude and duration of JNK activation in signaling response to oxidative stress. J Biol Chem 2007; 282:28395-28407. [PMID: 17681939 DOI: 10.1074/jbc.m705142200] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mitogen-activated protein kinases (MAPKs) are important mediators that integrate signaling from upstream pathways in response to various environmental cues. In order to control appropriate gene expression through phosphorylation of transcription factors, the activity of MAPKs must be tightly regulated by the actions coordinated between protein kinases and phosphatases. In this study, we explore the underlying mechanism through which the oxidative stress-activated c-Jun N-terminal kinases (JNKs), members of MAPKs, are regulated by dual specificity phosphatases (DUSPs). DUSPs are a group of enzymes that belong to the superfamily of protein-tyrosine phosphatases. They are able to recognize phospho-Ser/Thr and phospho-Tyr residues in substrates. Using quantitative real time PCR, we found that stimulation of human embryonic kidney 293T cells with H(2)O(2) or xanthine/xanthine oxidase led to inducible expression of multiple DUSPs. We used RNA interference to characterize the functional role of these DUSPs and found rapid and transient induction of DUSP1 and DUSP10 to be essential for determining the appropriate magnitude of JNK activation in response to oxidative stress. The transcription factor ATF2, which is phosphorylated and activated by JNK, is a critical mediator for inducible expression of DUSP1 and DUSP10 in this signaling pathway. We further demonstrated that DUSP4 and DUSP16, both showing significant late phase induction, dephosphorylate JNK effectively, causing the down-regulation of the signaling cascade. Thus, this study provides new insights into the role of several DUSPs that coordinate with each other to control the magnitude and duration of JNK activity in response to oxidative stress.
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Affiliation(s)
- Chun-Hung Teng
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Rd., Section 2, Taipei 11529, Taiwan
| | - Wen-Nin Huang
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Rd., Section 2, Taipei 11529, Taiwan
| | - Tzu-Ching Meng
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Rd., Section 2, Taipei 11529, Taiwan.
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32
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Abstract
Cancer can be perceived as a disease of communication between and within cells. The aberrations are pleiotropic, but mitogen-activated protein kinase (MAPK) pathways feature prominently. Here, we discuss recent findings and hypotheses on the role of MAPK pathways in cancer. Cancerous mutations in MAPK pathways are frequently mostly affecting Ras and B-Raf in the extracellular signal-regulated kinase pathway. Stress-activated pathways, such as Jun N-terminal kinase and p38, largely seem to counteract malignant transformation. The balance and integration between these signals may widely vary in different tumours, but are important for the outcome and the sensitivity to drug therapy.
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Affiliation(s)
- A S Dhillon
- The Beatson Institute for Cancer Research, Bearsden, Glasgow, UK.
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33
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Raman M, Earnest S, Zhang K, Zhao Y, Cobb MH. TAO kinases mediate activation of p38 in response to DNA damage. EMBO J 2007; 26:2005-14. [PMID: 17396146 PMCID: PMC1852793 DOI: 10.1038/sj.emboj.7601668] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Accepted: 03/07/2007] [Indexed: 12/17/2022] Open
Abstract
Thousand and one amino acid (TAO) kinases are Ste20p-related MAP kinase kinase kinases (MAP3Ks) that activate p38 MAPK. Here we show that the TAO kinases mediate the activation of p38 in response to various genotoxic stimuli. TAO kinases are activated acutely by ionizing radiation, ultraviolet radiation, and hydroxyurea. Full-length and truncated fragments of dominant negative TAOs inhibit the activation of p38 by DNA damage. Inhibition of TAO expression by siRNA also decreases p38 activation by these agents. Cells in which TAO kinases have been knocked down are less capable of engaging the DNA damage-induced G2/M checkpoint and display increased sensitivity to IR. The DNA damage kinase ataxia telangiectasia mutated (ATM) phosphorylates TAOs in vitro; radiation induces phosphorylation of TAO on a consensus site for phosphorylation by the ATM protein kinase in cells; and TAO and p38 activation is compromised in cells from a patient with ataxia telangiectasia that lack ATM. These findings indicate that TAO kinases are regulators of p38-mediated responses to DNA damage and are intermediates in the activation of p38 by ATM.
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Affiliation(s)
- Malavika Raman
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, USA
| | - Svetlana Earnest
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, USA
| | - Kai Zhang
- Department of Biochemistry, University of Texas, Southwestern Medical Center, Dallas, TX, USA
| | - Yingming Zhao
- Department of Biochemistry, University of Texas, Southwestern Medical Center, Dallas, TX, USA
| | - Melanie H Cobb
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, USA
- Department of Pharmacology, University of Texas, Southwestern Medical Center at Dallas, 6001 Forest Park Road, Dallas, TX 75390-9041, USA. Tel.: +1 214 645 6122; Fax: +1 214 645 6124; E-mail:
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34
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Boswell SA, Ongusaha PP, Nghiem P, Lee SW. The protective role of a small GTPase RhoE against UVB-induced DNA damage in keratinocytes. J Biol Chem 2006; 282:4850-4858. [PMID: 17170105 DOI: 10.1074/jbc.m610532200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
RhoE, a p53 target gene, was identified as a critical factor for the survival of human keratinocytes in response to UVB. The Rho family of GTPases regulates many aspects of cellular behavior through alterations to the actin cytoskeleton, acting as molecular switches cycling between the active, GTP-bound and the inactive, GDP-bound conformations. Unlike typical Rho family proteins, RhoE (also known as Rnd3) is GTPase-deficient and thus expected to be constitutively active. In this study, we investigated the response of cultured human keratinocyte cells to UVB irradiation. RhoE protein levels increase upon exposure to UVB, and ablation of RhoE induction through small interfering RNA resulted in a significant increase in apoptosis and a reduction in the levels of the pro-survival targets p21, Cox-2, and cyclin D1, as well as an increase of reactive oxygen species levels when compared with control cells. These data indicate that RhoE is a pro-survival factor acting upstream of p38, JNK, p21, and cyclin D1. HaCat cells expressing small interfering RNA to p53 indicate that RhoE functions independently of its known associates, p53 and Rho-associated kinase I (ROCK I). Targeted expression of RhoE in epidermis using skin-specific transgenic mouse model resulted in a significant reduction in the number of apoptotic cells following UVB irradiation. Thus, RhoE induction counteracts UVB-induced apoptosis and may serve as a novel target for the prevention of UVB-induced photodamage regardless of p53 status.
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Affiliation(s)
- Sarah A Boswell
- Dermatology Division, University of Washington, Seattle, Washington 98109
| | - Pat P Ongusaha
- Cutaneous Biology Research Center (CBRC), Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129 and the
| | - Paul Nghiem
- Dermatology Division, University of Washington, Seattle, Washington 98109
| | - Sam W Lee
- Cutaneous Biology Research Center (CBRC), Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129 and the.
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35
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Li DWC, Liu JP, Schmid PC, Schlosser R, Feng H, Liu WB, Yan Q, Gong L, Sun SM, Deng M, Liu Y. Protein serine/threonine phosphatase-1 dephosphorylates p53 at Ser-15 and Ser-37 to modulate its transcriptional and apoptotic activities. Oncogene 2006; 25:3006-22. [PMID: 16501611 DOI: 10.1038/sj.onc.1209334] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We have previously demonstrated that the serine/threonine protein phosphatase-1 (PP-1) plays an important role in promoting cell survival. However, the molecular mechanisms by which PP-1 promotes survival remain largely unknown. In the present study, we provide evidence to show that PP-1 can directly dephosphorylate a master regulator of apoptosis, p53, to negatively modulate its transcriptional and apoptotic activities, and thus to promote cell survival. As a transcriptional factor, the function of p53 can be greatly regulated by phosphorylation and dephosphorylation. While the kinases responsible for phosphorylation of the 17 serine/threonine sites have been identified, the dephosphorylation of these sites remains largely unknown. In the present study, we demonstrate that PP-1 can dephosphorylate p53 at Ser-15 and Ser-37 through co-immunoprecipitation, in vitro and in vivo dephosphorylation assays, overexpression and silence of the gene encoding the catalytic subunit for PP-1. We further show that mutations mimicking constitutive dephosphorylation or phosphorylation of p53 at these sites attenuate or enhance its transcriptional activity, respectively. As a result of the changed p53 activity, expression of the downstream apoptosis-related genes such as bcl-2 and bax is accordingly altered and the apoptotic events are either largely abrogated or enhanced. Thus, our results demonstrate that PP-1 directly dephosphorylates p53, and dephosphorylation of p53 has as important impact on its functions as phosphorylation does. In addition, our results reveal that one of the molecular mechanisms by which PP-1 promotes cell survival is to dephosphorylate p53, and thus negatively regulate p53-dependent death pathway.
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MESH Headings
- Amino Acid Substitution
- Animals
- Apoptosis/drug effects
- Apoptosis/genetics
- Apoptosis/physiology
- Cell Line/drug effects
- Cell Line/enzymology
- Epithelial Cells/drug effects
- Epithelial Cells/metabolism
- Genes, Reporter
- Genes, bcl-2
- Genes, p53
- Humans
- Immunoprecipitation
- Lens, Crystalline/cytology
- Marine Toxins
- Mice
- Mice, Knockout
- Okadaic Acid/pharmacology
- Oxazoles/pharmacology
- Phosphoprotein Phosphatases/antagonists & inhibitors
- Phosphoprotein Phosphatases/genetics
- Phosphoprotein Phosphatases/physiology
- Phosphorylation/drug effects
- Phosphoserine/metabolism
- Protein Binding
- Protein Interaction Mapping
- Protein Phosphatase 1
- Protein Processing, Post-Translational/drug effects
- Protein Processing, Post-Translational/physiology
- Proto-Oncogene Proteins c-bcl-2/biosynthesis
- RNA Interference
- RNA, Small Interfering/pharmacology
- Recombinant Fusion Proteins/physiology
- Transcription, Genetic/drug effects
- Transcription, Genetic/physiology
- Tumor Suppressor Protein p53/chemistry
- Tumor Suppressor Protein p53/metabolism
- bcl-2-Associated X Protein/biosynthesis
- bcl-2-Associated X Protein/genetics
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Affiliation(s)
- D W-C Li
- The Hormel Institute, University of Minnesota, Austin, 55912, USA.
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36
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Romanov VV, James CH, Sherrington PD, Pettitt AR. Basic fibroblast growth factor suppresses p53 activation in the neoplastic cells of a proportion of patients with chronic lymphocytic leukaemia. Oncogene 2005; 24:6855-60. [PMID: 16103882 DOI: 10.1038/sj.onc.1208895] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
p53 is the most frequently inactivated gene in human cancers, reflecting its pivotal role in maintaining genomic integrity. The present study was conducted to explore the possibility that tumour cells with no intrinsic defects of the p53 pathway might nevertheless acquire p53 dysfunction through extrinsic suppression of the pathway by microenvironmental factors. Neoplastic cells from patients with chronic lymphocytic leukaemia (CLL) were cultured in the presence or absence of basic fibroblast growth factor (bFGF) and exposed to ionizing radiation (IR) to induce p53 accumulation. bFGF is greatly increased in the plasma of CLL patients and can suppress p53 activation in some experimental models. IR induced a marked increase in p53 levels in 28 samples from 24 patients. bFGF inhibited IR-induced p53 accumulation to some extent in most of these samples and by more than 50% in seven samples from seven patients. Suppression of p53 activation by bFGF was frequently but not always accompanied by upregulation of the p53-inhibitory protein MDM2 and/or phosphorylation of MDM2 at serine 166, and was associated with impaired transcriptional activation of the p53 target gene p21. These observations provide the first demonstration in human cancer cells that the p53 pathway can be suppressed by factors in the tumour-cell microenvironment.
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Affiliation(s)
- Vadim V Romanov
- Department of Haematology, Royal Liverpool University Hospital, Level 2 Ducan Building, Prescot Street, Liverpool, Merseyside L7 8XP, UK
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37
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Levav-Cohen Y, Goldberg Z, Zuckerman V, Grossman T, Haupt S, Haupt Y. C-Abl as a modulator of p53. Biochem Biophys Res Commun 2005; 331:737-49. [PMID: 15865930 DOI: 10.1016/j.bbrc.2005.03.152] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2005] [Indexed: 01/10/2023]
Abstract
P53 is renowned as a cellular tumor suppressor poised to instigate remedial responses to various stress insults that threaten DNA integrity. P53 levels and activities are kept under tight regulation involving a complex network of activators and inhibitors, which determine the type and extent of p53 growth inhibitory signaling. Within this complexity, the p53-Mdm2 negative auto-regulatory loop serves as a major route through which intra- and extra-cellular stress signals are channeled to appropriate p53 responses. Mdm2 inhibits p53 transcriptional activities and through its E3 ligase activity promotes p53 proteasomal degradation either within the nucleus or following nuclear export. Upon exposure to stress signals these actions of Mdm2 have to be moderated, or even interrupted, in order to allow sufficient p53 to accumulate in an active form. Multiple mechanisms involving a variety of factors have been demonstrated to mediate this interruption. C-Abl is a critical factor that under physiological conditions is required for the maximal and efficient accumulation of active p53 in response to DNA damage. C-Abl protects p53 by antagonizing the inhibitory effect of Mdm2, an action that requires a direct interplay between c-Abl and Mdm2. In addition, c-Abl protects p53 from other inhibitors of p53, such as the HPV-E6/E6AP complex, that inhibits and degrades p53 in HPV-infected cells. Surprisingly, the oncogenic form of c-Abl, the Bcr-Abl fusion protein in CML cells, also promotes the accumulation of wt p53. However, in contrast to the activation of p53 by c-Abl, its oncogenic form, Bcr-Abl, counteracts the growth inhibitory activities of p53 by modulating the p53-Mdm2 loop. Thus, it appears that by modulating the p53-Mdm2 loop, c-Abl and its oncogenic forms critically determine the type and extent of the cellular response to DNA damage.
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Affiliation(s)
- Yaara Levav-Cohen
- Lautenberg Center for General and Tumor Immunology, The Hebrew University Hadassah Medical School, Jerusalem 91120, Israel
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38
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Weber HO, Ludwig RL, Morrison D, Kotlyarov A, Gaestel M, Vousden KH. HDM2 phosphorylation by MAPKAP kinase 2. Oncogene 2005; 24:1965-72. [PMID: 15688025 DOI: 10.1038/sj.onc.1208389] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
p53 stability is regulated by HDM2, a RING domain protein that acts as an E3 ligase to ubiquitinate p53 and target its degradation. Phosphorylation of HDM2 on serine 166 by AKT has been shown to enhance HDM2 activity and promote the degradation of p53. Here, we show that MAPKAP kinase 2 (MK2) can phosphorylate HDM2 on serine 157 and 166 in vitro. Treatment of cells with anisomycin, which activates MK2, also results in phosphorylation of HDM2 on serine 157 and 166 in vivo. Mutation of the MK2 phosphorylation sites in HDM2 to aspartic acid renders HDM2 slightly more active in the degradation of p53, and mouse cells deficient for MK2 show reduced Mdm2 phosphorylation and elevated levels of p53 protein. Together, our results suggest that MK2 may act to dampen the extent and duration of the p53 response.
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Affiliation(s)
- Hans Oliver Weber
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK
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39
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Manke IA, Nguyen A, Lim D, Stewart MQ, Elia AEH, Yaffe MB. MAPKAP kinase-2 is a cell cycle checkpoint kinase that regulates the G2/M transition and S phase progression in response to UV irradiation. Mol Cell 2005; 17:37-48. [PMID: 15629715 DOI: 10.1016/j.molcel.2004.11.021] [Citation(s) in RCA: 325] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2004] [Revised: 10/05/2004] [Accepted: 10/27/2004] [Indexed: 11/29/2022]
Abstract
The cellular response to DNA damage is mediated by evolutionarily conserved Ser/Thr kinases, phosphorylation of Cdc25 protein phosphatases, binding to 14-3-3 proteins, and exit from the cell cycle. To investigate DNA damage responses mediated by the p38/stress-activated protein kinase (SAPK) axis of signaling, the optimal phosphorylation motifs of mammalian p38alpha SAPK and MAPKAP kinase-2 were determined. The optimal substrate motif for MAPKAP kinase-2, but not for p38 SAPK, closely matches the 14-3-3 binding site on Cdc25B/C. We show that MAPKAP kinase-2 is directly responsible for Cdc25B/C phosphorylation and 14-3-3 binding in vitro and in response to UV-induced DNA damage within mammalian cells. Downregulation of MAPKAP kinase-2 eliminates DNA damage-induced G2/M, G1, and intra S phase checkpoints. We propose that MAPKAP kinase-2 is a new member of the DNA damage checkpoint kinase family that functions in parallel with Chk1 and Chk2 to integrate DNA damage signaling responses and cell cycle arrest in mammalian cells.
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Affiliation(s)
- Isaac A Manke
- Center for Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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40
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Abstract
Cancers arise as a consequence of the accumulation of multiple genetic mutations in a susceptible cell, resulting in perturbation of regulatory networks that control proliferation, survival, and cellular function. Here, the sources of cellular stress that can cause oncogenic mutations and the responses of cells to DNA damage are reviewed. The role of different repair pathways and the potential for cell- and tissue-specific reliance on individual repair mechanisms are discussed. Evidence for cell- and tissue-specific activation of p53-mediated growth arrest and apoptosis after exposure to an individual genotoxin is assessed and some of the potential mediators of these different responses are provided. These cell- and tissue-specific responses to particular forms of DNA damage are likely to be key determinants of tissue-specific tumour susceptibility, and there is good evidence for genetic variations in these responses. The role that genotoxic agents play in altering the microenvironment to produce indirect effects on tumourigenesis through altered production of free radicals and cytokines that are characteristic of inflammatory-type processes is also evaluated. Changes to the microenvironment as direct or indirect effects of genotoxic stress can be involved in both tumour initiation and progression and may even be a prerequisite for tumourigenesis. Therefore, tumour susceptibility after endogenous or exogenous genotoxic stress represents a balance between cell-intrinsic responses of target cells and changes to the microenvironment. A fuller understanding of cell- and tissue-specific responses, alterations to the microenvironment, and genetic modifiers of these responses could lead to novel prevention and therapeutic strategies for common forms of human malignancy.
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Affiliation(s)
- Philip J Coates
- Cancer Biology and Clinical Pathology Unit, Division of Pathology and Neurosciences, University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK.
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41
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He Z, Cho YY, Ma WY, Choi HS, Bode AM, Dong Z. Regulation of Ultraviolet B-induced Phosphorylation of Histone H3 at Serine 10 by Fyn Kinase. J Biol Chem 2005; 280:2446-54. [PMID: 15537652 DOI: 10.1074/jbc.m402053200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Ultraviolet B (UVB) induces phosphorylation of histone H3 at serine 10, and mitogen-activated protein kinases are involved in this signal transduction pathway. Here we provide evidence that Fyn kinase, a member of the Src kinase family, is involved in the UVB-induced phosphorylation of histone H3 at serine 10. UVB distinctly increased Fyn kinase activity and phosphorylation. Fyn kinase inhibitors 4-amino-5-(4-chlorophenyl)-7(t-butyl)pyrazol(3,4-d)pyramide and leflunomide, an Src kinase inhibitor, suppressed both UVB-induced phosphorylation of histone H3 at serine 10 and Fyn kinase activity and phosphorylation. UVB-induced phosphorylation of histone H3 at serine 10 was blocked by either a dominant-negative mutant of Fyn (DNM-Fyn) kinase or small interfering RNA of Fyn kinase. UVB-induced phosphorylation and activities of ERKs and protein kinase B/Akt were markedly inhibited by DNM-Fyn kinase. However, DNM-Fyn kinase did not inhibit UVB-induced phosphorylation of p38 MAPK or c-Jun N-terminal kinases. Active Fyn kinase phosphorylated histone H3 at serine 10 in vitro, and the phosphorylated Fyn kinase could translocate into the nucleus of HaCaT cells. These results indicate that Fyn kinase plays a key role in the UVB-induced phosphorylation of histone H3 at serine 10.
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Affiliation(s)
- Zhiwei He
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
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42
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Bode AM, Dong Z. Signal transduction pathways in cancer development and as targets for cancer prevention. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2005; 79:237-97. [PMID: 16096030 DOI: 10.1016/s0079-6603(04)79005-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ann M Bode
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
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43
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Wheeler DL, Martin KE, Ness KJ, Li Y, Dreckschmidt NE, Wartman M, Ananthaswamy HN, Mitchell DL, Verma AK. Protein kinase C epsilon is an endogenous photosensitizer that enhances ultraviolet radiation-induced cutaneous damage and development of squamous cell carcinomas. Cancer Res 2004; 64:7756-65. [PMID: 15520180 DOI: 10.1158/0008-5472.can-04-1881] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Chronic exposure to UV radiation (UVR), especially in the UVA (315-400 nm) and UVB (280-315 nm) spectrum of sunlight, is the major risk factor for the development of nonmelanoma skin cancer. UVR is a complete carcinogen, which both initiates and promotes carcinogenesis. We found that protein kinase C epsilon (PKCepsilon), a member of the phospholipid-dependent threonine/serine kinase family, is an endogenous photosensitizer, the overexpression of which in the epidermis increases the susceptibility of mice to UVR-induced cutaneous damage and development of squamous cell carcinoma. The PKCepsilon transgenic mouse (FVB/N) lines 224 and 215 overexpressed 8- and 18-fold PKCepsilon protein, respectively, over endogenous levels in basal epidermal cells. UVR exposure (1 kJ/m(2) three times weekly) induced irreparable skin damage in high PKCepsilon-overexpressing mouse line 215. However, the PKCepsilon transgenic mouse line 224, when exposed to UVR (2 kJ/m(2) three times weekly), exhibited minimum cutaneous damage but increased squamous cell carcinoma multiplicity by 3-fold and decreased tumor latency by 12 weeks. UVR exposure of PKCepsilon transgenic mice compared with wild-type littermates (1) elevated the levels of neither cyclobutane pyrimidine dimer nor pyrimidine (6-4) pyrimidone dimer, (2) reduced the appearance of sunburn cells, (3) induced extensive hyperplasia and increased the levels of mouse skin tumor promoter marker ornithine decarboxylase, and (4) elevated the levels of tumor necrosis factor alpha (TNFalpha) and other growth stimulatory cytokines, granulocyte colony-stimulating factor, and granulocyte macrophage colony-stimulating factor. The role of TNFalpha in UVR-induced cutaneous damage was evaluated using PKCepsilon transgenic mice deficient in TNFalpha. UVR treatment three times weekly for 13 weeks at 2 kJ/m(2) induced severe cutaneous damage in PKCepsilon transgenic mice (line 215), which was partially prevented in PKCepsilon-transgenic TNFalpha-knockout mice. Taken together, the results indicate that PKCepsilon signals UVR-induced TNFalpha release that is linked, at least in part, to the photosensitivity of PKCepsilon transgenic mice.
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Affiliation(s)
- Deric L Wheeler
- Department of Human Oncology, Medical School, University of Wisconsin, Madison, Wisconsin 53792, USA
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44
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Abstract
Interest in the tumour suppressor p53 has generated much information regarding the complexity of its function and regulation in carcinogenesis. However, gaps still exist in our knowledge regarding the role of p53 post-translational modifications in carcinogenesis and cancer prevention. A thorough understanding of p53 will be extremely useful in the development of new strategies for treating and preventing cancer, including restoration of p53 function and selective killing of tumours with mutant TP53.
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Affiliation(s)
- Ann M Bode
- The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, Minnesota 55912, USA
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45
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Nakagawa S, Ohtani T, Mizuashi M, Mollah ZUA, Ito Y, Tagami H, Aiba S. p38 Mitogen-Activated Protein Kinase Mediates Dual Role of Ultraviolet B Radiation in Induction of Maturation and Apoptosis of Monocyte-Derived Dendritic Cells. J Invest Dermatol 2004; 123:361-70. [PMID: 15245437 DOI: 10.1111/j.0022-202x.2004.23238.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Although ultraviolet B (UVB) induces apoptosis and functional perturbations in dendritic cells (DC), for example, Langerhans cells (LC), it also stimulates some LC into maturation after irradiation in vivo. To analyze its reciprocal effects on DC, we elucidated the direct effect of UVB on DC in vitro using human monocyte-derived DC (MoDC). UVB from 50 to 200 J per m2 stimulated the maturation of MoDC with (1) augmented expression of CD86 and HLA-DR, (2) enhanced production of IL-1beta, IL-6, IL-8, and TNF-alpha at both the mRNA and protein levels, and (3) enhanced allostimulatory capacity on a per-cell basis, whereas the exceeded doses induced apoptotic cell death. Western-blot analysis of MoDC after UVB demonstrated a concentration-dependent phosphorylation of p38- and c-JUN N-terminal kinase (JNK)-mitogen-activated protein kinases (MAPK), but not that of extracellular signal-regulated kinases. p38 MAPK-inhibitor, SB203580, inhibited both UVB-induced maturation and apoptosis of MoDC. Interestingly, MoDC that had undergone apoptosis exhibited an augmented expression of HLA-DR without upregulation of CD86 antigen, suggesting their tolerogenic phenotype. Thus, our study revealed a dual effect of UVB, to stimulate maturation or to induce apoptosis in MoDC, depending on the dosage, via p38 MAPK pathway.
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Affiliation(s)
- Satoshi Nakagawa
- Department of Dermatology, Tohoku University Graduate School of Medicine, Sendai, Japan
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46
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Hildesheim J, Fornace AJ. The dark side of light: the damaging effects of UV rays and the protective efforts of MAP kinase signaling in the epidermis. DNA Repair (Amst) 2004; 3:567-80. [PMID: 15135725 DOI: 10.1016/j.dnarep.2004.02.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2004] [Indexed: 12/23/2022]
Affiliation(s)
- Jeffrey Hildesheim
- Gene Response Section, Center for Cancer Research, NCI, NIH, Building 37, Room 6144, 37 Convent Drive, Bethesda, MD 20892, USA.
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47
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Heck DE, Gerecke DR, Vetrano AM, Laskin JD. Solar ultraviolet radiation as a trigger of cell signal transduction. Toxicol Appl Pharmacol 2004; 195:288-97. [PMID: 15020191 DOI: 10.1016/j.taap.2003.09.028] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2003] [Accepted: 09/12/2003] [Indexed: 10/26/2022]
Abstract
Ultraviolet light radiation in sunlight is known to cause major alterations in growth and differentiation patterns of exposed human tissues. The specific effects depend on the wavelengths and doses of the light, and the nature of the exposed tissue. Both growth inhibition and proliferation are observed, as well as inflammation and immune suppression. Whereas in the clinical setting, these responses may be beneficial, for example, in the treatment of psoriasis and atopic dermatitis, as an environmental toxicant, ultraviolet light can induce significant tissue damage. Thus, in the eye, ultraviolet light causes cataracts, while in the skin, it induces premature aging and the development of cancer. Although ultraviolet light can damage many tissue components including membrane phospholipids, proteins, and nucleic acids, it is now recognized that many of its cellular effects are due to alterations in growth factor- and cytokine-mediated signal transduction pathways leading to aberrant gene expression. It is generally thought that reactive oxygen intermediates are mediators of some of the damage induced by ultraviolet light. Generated when ultraviolet light is absorbed by endogenous photosensitizers in the presence of molecular oxygen, reactive oxygen intermediates and their metabolites induce damage by reacting with cellular electrophiles, some of which can directly initiate cell signaling processes. In an additional layer of complexity, ultraviolet light-damaged nucleic acids initiate signaling during the activation of repair processes. Thus, mechanisms by which solar ultraviolet radiation triggers cell signal transduction are multifactorial. The present review summarizes some of the mechanisms by which ultraviolet light alters signaling pathways as well as the genes important in the beneficial and toxic effects of ultraviolet light.
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Affiliation(s)
- Diane E Heck
- Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ 08854, USA
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Affiliation(s)
- Ann M Bode
- University of Minnesota, Hormel Institute, Austin, Minnesota 55912, USA
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Melnikova VO, Santamaria AB, Bolshakov SV, Ananthaswamy HN. Mutant p53 is constitutively phosphorylated at Serine 15 in UV-induced mouse skin tumors: involvement of ERK1/2 MAP kinase. Oncogene 2003; 22:5958-66. [PMID: 12955074 DOI: 10.1038/sj.onc.1206595] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Upon DNA damage, phosphorylation and nuclear translocation of wild-type p53 tumor suppressor protein signals its functional activation. However, very little is known about phosphorylation and localization of mutant p53. We found that mutant p53 protein in UV-induced murine primary skin tumors and cultured cell lines was constitutively phosphorylated at serine 15 residue and localized in the cell's nuclei. To investigate the mechanism of constitutive phosphorylation of mutant p53, we tested the involvement of a wide range of protein kinases and found that ERK1/2 mitogen-activated protein kinase was physically associated with mutant p53 in the nucleus. Addition of active recombinant ERK2 kinase protein in vitro to immunoprecipitated mutant p53 resulted in increased phosphorylation at serine 15. Furthermore, ERK1/2 activity was higher in tumor cells than normal cells, suggesting that phosphorylation of mutant p53 at serine 15 depends on the level of ERK1/2 activation. Interestingly, accumulation of mutant p53 in tumor cells was paralleled by low levels of Murine Double Minute 2 protein (MDM2) expression. However, when MDM2 was overexpressed, the fraction of mutant p53 that was phosphorylated at serine 15 resisted degradation, whereas the level of total p53 decreased, suggesting that phosphorylation at serine 15 and downregulation of MDM2 protein may both contribute to stabilization of mutant p53 in tumor cells.
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Affiliation(s)
- Vladislava O Melnikova
- Department of Immunology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Box 178, Houston, TX 77030-4009, USA
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Louria-Hayon I, Grossman T, Sionov RV, Alsheich O, Pandolfi PP, Haupt Y. The promyelocytic leukemia protein protects p53 from Mdm2-mediated inhibition and degradation. J Biol Chem 2003; 278:33134-41. [PMID: 12810724 DOI: 10.1074/jbc.m301264200] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The p53 protein is kept labile under normal conditions. This regulation is governed largely by its major negative regulator, Mdm2. In response to stress however, p53 accumulates and becomes activated. For this to occur, the inhibitory effects of Mdm2 have to be neutralized. Here we investigated the role of the promyelocytic leukemia protein (PML) in the activation of p53 in response to stress. We found that PML is critical for the accumulation of p53 in response to DNA damage under physiological conditions. PML protects p53 from Mdm2-mediated ubiquitination and degradation, and from inhibition of apoptosis. PML neutralizes the inhibitory effects of Mdm2 by prolonging the stress-induced phosphorylation of p53 on serine 20, a site of the checkpoint kinase 2 (Chk2). PML recruits Chk2 and p53 into the PML nuclear bodies and enhances p53/Chk2 interaction. Our results provide a novel mechanistic explanation for the cooperation between PML and p53 in response to DNA damage.
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Affiliation(s)
- Igal Louria-Hayon
- Lautenberg Center for General and Tumor Immunology, The Hebrew University Hadassah Medical School, Jerusalem 91120, Israel
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