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Chen Y, Williams V, Filippova M, Filippov V, Duerksen-Hughes P. Viral carcinogenesis: factors inducing DNA damage and virus integration. Cancers (Basel) 2014; 6:2155-86. [PMID: 25340830 PMCID: PMC4276961 DOI: 10.3390/cancers6042155] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 10/03/2014] [Accepted: 10/09/2014] [Indexed: 12/13/2022] Open
Abstract
Viruses are the causative agents of 10%-15% of human cancers worldwide. The most common outcome for virus-induced reprogramming is genomic instability, including accumulation of mutations, aberrations and DNA damage. Although each virus has its own specific mechanism for promoting carcinogenesis, the majority of DNA oncogenic viruses encode oncogenes that transform infected cells, frequently by targeting p53 and pRB. In addition, integration of viral DNA into the human genome can also play an important role in promoting tumor development for several viruses, including HBV and HPV. Because viral integration requires the breakage of both the viral and the host DNA, the integration rate is believed to be linked to the levels of DNA damage. DNA damage can be caused by both endogenous and exogenous factors, including inflammation induced by either the virus itself or by co-infections with other agents, environmental agents and other factors. Typically, cancer develops years to decades following the initial infection. A better understanding of virus-mediated carcinogenesis, the networking of pathways involved in transformation and the relevant risk factors, particularly in those cases where tumorigenesis proceeds by way of virus integration, will help to suggest prophylactic and therapeutic strategies to reduce the risk of virus-mediated cancer.
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Affiliation(s)
- Yan Chen
- Department of Basic Science, Loma Linda University, Loma Linda, CA 92354, USA.
| | - Vonetta Williams
- Department of Basic Science, Loma Linda University, Loma Linda, CA 92354, USA.
| | - Maria Filippova
- Department of Basic Science, Loma Linda University, Loma Linda, CA 92354, USA.
| | - Valery Filippov
- Department of Basic Science, Loma Linda University, Loma Linda, CA 92354, USA.
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Klingenberg M, Becker J, Eberth S, Kube D, Wilting J. The NADPH oxidase inhibitor imipramine-blue in the treatment of Burkitt lymphoma. Mol Cancer Ther 2014; 13:833-41. [PMID: 24482381 DOI: 10.1158/1535-7163.mct-13-0688] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Burkitt lymphoma is a rare malignancy arising from B cells. Current chemotherapeutic regimens achieve excellent overall survival rates in children, but less impressive rates in adults. There are cases with poor outcome caused by toxic effects of the therapy, tumor lysis syndrome, or metastatic spread of lymphomas to the central nervous system. Modulators of reactive oxygen species are currently discussed as potential drugs for the treatment of cancer. The NADPH oxidase 4 inhibitor imipramine-blue might satisfy the aforementioned requirements, and was studied here. We used MTT assay, crystal violet assay, and thymidine 3H-incorporation assay to analyze the effects of imipramine-blue on Burkitt lymphoma (BL2, BL2B95, BL30B95, BL41B95), neuroblastoma (KELLY, SH-SY5Y, SMS-KAN), cervix carcinoma (HeLa), breast cancer (MDA-MB231), angiosarcoma (AS-M), human embryonic kidney (HEK293WT), and nonmalignant (FLP1) cell lines. The effects of imipramine-blue on BL2B95 cells in vivo were investigated in xenografts on the chick chorioallantoic membrane (CAM). We report that imipramine-blue is a potent growth inhibitor for several cancer cell lines in vitro with IC(50) values comparable to those of doxorubicin (0.16-7.7 μmol/L). Tumor size of BL2B95 cells inoculated in the CAM was reduced significantly (P < 0.05) after treatment with 10 μmol/L imipramine-blue. Lymphogenic dissemination of BL2B95 and the formation of blood and lymphatic vessels in experimental tumors were not affected. We show that imipramine-blue can be used to decrease the viability of cancer cell lines in vitro and in vivo. Imipramine-blue reduces the size of experimental Burkitt lymphoma significantly but does not affect the dissemination of BL2B95 cells, angiogenesis, and lymphangiogenesis.
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Affiliation(s)
- Marcel Klingenberg
- Authors' Affiliations: Departments of Anatomy and Cell Biology and Hematology and Oncology, University Medicine Goettingen, Goettingen, Germany
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Huang SY, Fang CY, Wu CC, Tsai CH, Lin SF, Chen JY. Reactive oxygen species mediate Epstein-Barr virus reactivation by N-methyl-N'-nitro-N-nitrosoguanidine. PLoS One 2013; 8:e84919. [PMID: 24376853 PMCID: PMC3869928 DOI: 10.1371/journal.pone.0084919] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 11/20/2013] [Indexed: 12/15/2022] Open
Abstract
N-nitroso compounds (NOCs) and Epstein-Barr virus (EBV) reactivation have been suggested to play a role in the development of nasopharyngeal carcinoma (NPC). Although chemicals have been shown to be a risk factor contributing to the carcinogenesis of NPC, the underlying mechanism is not fully understood. We demonstrated recently that N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) enhances the genomic instability and tumorigenicity of NPC cells via induction of EBV reactivation. However, the mechanisms that trigger EBV reactivation from latency remain unclear. Here, we address the role of ROS in induction of EBV reactivation under MNNG treatment. EBV reactivation was induced in over 70% of EBV-positive NA cells and the promoter of Rta (Rp) was activated after MNNG treatment. Inhibitor experiments revealed ATM, p38 MAPK and JNK were activated by ROS and involved in MNNG-induced EBV reactivation. Significantly, ROS scavengers N-acetyl-L-cysteine (NAC), catalase and reduced glutathione inhibited EBV reactivation under MNNG and H₂O₂ treatment, suggesting ROS mediate EBV reactivation. The p53 was essential for EBV reactivation and the Rp activation by MNNG. Moreover, the p53 was phosphorylated, translocated into nucleus, and bound to Rp following ROS stimulation. The results suggest ROS play an important role in initiation of EBV reactivation by MNNG through a p53-dependent mechanism. Our findings demonstrate novel signaling mechanisms used by NOCs to induce EBV reactivation and provide a novel insight into NOCs link the EBV reactivation in the contribution to the development of NPC. Notably, this study indicates that antioxidants might be effective for inhibiting N-nitroso compound-induced EBV reactivation and therefore could be promising preventive and therapeutic agents for EBV reactivation-associated malignancies.
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Affiliation(s)
- Sheng-Yen Huang
- Graduate Program of Biotechnology in Medicine of National Tsing Hua University and National Health Research Institutes, Hsinchu, Taiwan
- Institute of Biotechnology, Department of Life Sciences, National Tsing Hua University, Hsinchu, Taiwan
- National Institute of Cancer Research, National Health Research Institutes, Miaoli County, Taiwan
| | - Chih-Yeu Fang
- National Institute of Cancer Research, National Health Research Institutes, Miaoli County, Taiwan
| | - Chung-Chun Wu
- National Institute of Cancer Research, National Health Research Institutes, Miaoli County, Taiwan
| | - Ching-Hwa Tsai
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Su-Fang Lin
- National Institute of Cancer Research, National Health Research Institutes, Miaoli County, Taiwan
| | - Jen-Yang Chen
- Graduate Program of Biotechnology in Medicine of National Tsing Hua University and National Health Research Institutes, Hsinchu, Taiwan
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
- National Institute of Cancer Research, National Health Research Institutes, Miaoli County, Taiwan
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Interplay among viral antigens, cellular pathways and tumor microenvironment in the pathogenesis of EBV-driven lymphomas. Semin Cancer Biol 2013; 23:441-56. [DOI: 10.1016/j.semcancer.2013.07.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 07/24/2013] [Accepted: 07/26/2013] [Indexed: 11/22/2022]
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Reactive oxygen species are induced by Kaposi's sarcoma-associated herpesvirus early during primary infection of endothelial cells to promote virus entry. J Virol 2012; 87:1733-49. [PMID: 23175375 DOI: 10.1128/jvi.02958-12] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The entry of Kaposi's sarcoma-associated herpesvirus (KSHV) into human dermal microvascular endothelial cells (HMVEC-d), natural in vivo target cells, via macropinocytosis is initiated through a multistep process involving the binding of KSHV envelope glycoproteins with cell surface α3β1, αVβ3, and αVβ5 integrin molecules and tyrosine kinase ephrin-A2 receptor, followed by the activation of preexisting integrin-associated signaling molecules such as focal adhesion kinase (FAK), Src, c-Cbl, phosphoinositide 3-kinase (PI-3K), and Rho-GTPases. Many viruses, including KSHV, utilize cellular reactive oxygen species (ROS) for viral genomic replication and survival within host cells; however, the role of ROS in early events of viral entry and the induction of signaling has not been elucidated. Here we show that KSHV induced ROS production very early during the infection of HMVEC-d cells and that ROS production was sustained over the observation period (24 h postinfection). ROS induction was dependent on the binding of KSHV to the target cells, since pretreatment of the virus with heparin abolished ROS induction. Pretreatment of HMVEC-d cells with the antioxidant N-acetylcysteine (NAC) significantly inhibited KSHV entry, and consequently gene expression, without affecting virus binding. In contrast, H(2)O(2) treatment increased the levels of KSHV entry and infection. In addition, NAC inhibited KSHV infection-induced translocation of αVβ3 integrin into lipid rafts, actin-dependent membrane perturbations, such as blebs, observed during macropinocytosis, and activation of the signal molecules ephrin-A2 receptor, FAK, Src, and Rac1. In contrast, H(2)O(2) treatment increased the activation of ephrin-A2, FAK, Src, and Rac1. These studies demonstrate that KSHV infection induces ROS very early during infection to amplify the signaling pathways necessary for its efficient entry into HMVEC-d cells via macropinocytosis.
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Frappier L. Contributions of Epstein-Barr nuclear antigen 1 (EBNA1) to cell immortalization and survival. Viruses 2012; 4:1537-1547. [PMID: 23170171 PMCID: PMC3499818 DOI: 10.3390/v4091537] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 08/14/2012] [Accepted: 08/27/2012] [Indexed: 12/13/2022] Open
Abstract
Epstein–Barr virus (EBV) immortalizes host cells as part of its latent mode of infection. As a result of this ability to promote cell proliferation and survival, EBV infection contributes to the development of several kinds of B-cell lymphomas and epithelial tumours. The EBV Epstein–Barr nuclear antigen 1 (EBNA1) protein is the only EBV protein expressed in all EBV-associated tumours and plays multiple important roles in EBV latency. In addition to its well-studied roles in viral DNA replication, segregation and transcriptional activation, several studies have identified roles of EBNA1 in manipulating cellular processes that result in reduced apoptosis and increased cell survival. This review discusses these cellular effects of EBNA1 and mechanisms by which they occur.
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Affiliation(s)
- Lori Frappier
- Department of Molecular Genetics, University of Toronto, 1 Kings College Circle, Toronto, ON M5S 1A8, Canada
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59
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Hu ZY, Wang J, Cheng G, Zhu XF, Huang P, Yang D, Zeng YX. Apogossypolone targets mitochondria and light enhances its anticancer activity by stimulating generation of singlet oxygen and reactive oxygen species. CHINESE JOURNAL OF CANCER 2012; 30:41-53. [PMID: 21192843 PMCID: PMC4012262 DOI: 10.5732/cjc.010.10295] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Apogossypolone (ApoG2), a novel derivative of gossypol, has been shown to be a potent inhibitor of antiapoptotic Bcl-2 family proteins and to have antitumor activity in multiple types of cancer cells. Recent reports suggest that gossypol stimulates the generation of cellular reactive oxygen species (ROS) in leukemia and colorectal carcinoma cells; however, gossypol-mediated cell death in leukemia cells was reported to be ROS-independent. This study was conducted to clarify the effect of ApoG2-induced ROS on mitochondria and cell viability, and to further evaluate its utility as a treatment for nasopharyngeal carcinoma (NPC). We tested the photocytotoxicity of ApoG2 to the poorly differentiated NPC cell line CNE-2 using the ROS-generating TL/10 illumination system. The rapid ApoG2-induced cell death was partially reversed by the antioxidant N-acetyl-L-cysteine (NAC), but the ApoG2-induced reduction of mitochondrial membrane potential (MMP) was not reversed by NAC. In the presence of TL/10 illumination, ApoG2 generated massive amounts of singlet oxygen and was more effective in inhibiting cell growth than in the absence of illumination. We also determined the influence of light on the anti-proliferative activity of ApoG2 using a CNE-2–xenograft mouse model. ApoG2 under TL/10 illumination healed tumor wounds and suppressed tumor growth more effectively than ApoG2 treatment alone. These results indicate that the ApoG2-induced CNE-2 cell death is partly ROS-dependent. ApoG2 may be used with photodynamic therapy (PDT) to treat NPC.
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Affiliation(s)
- Zhe-Yu Hu
- State Key Laboratory of Oncology in South China, Guangzhou, Guangdong 510060, PR China
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60
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Bonner MY, Arbiser JL. Targeting NADPH oxidases for the treatment of cancer and inflammation. Cell Mol Life Sci 2012; 69:2435-42. [PMID: 22581366 DOI: 10.1007/s00018-012-1017-2] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 04/18/2012] [Accepted: 04/20/2012] [Indexed: 10/28/2022]
Abstract
NADPH oxidases are a family of oxidases that utilize molecular oxygen to generate hydrogen peroxide and superoxide, thus indicating physiological functions of these highly reactive and short-lived species. The regulation of these NADPH oxidases (nox) enzymes is complex, with many members of this family exhibiting complexity in terms of subunit composition, cellular location, and tissue-specific expression. While the complexity of the nox family (Nox1-5, Duox1, 2) is daunting, the complexity also allows for targeting of NADPH oxidases in disease states. In this review, we discuss which inflammatory and malignant disorders can be targeted by nox inhibitors, as well as clinical experience in the use of such inhibitors.
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Affiliation(s)
- Michael Y Bonner
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA 30322, USA
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HU ZHEYU, XU FEI, SUN RUI, CHEN YANFENG, ZHANG DONGSHENG, FAN YUHUA, SUN JIAN. Apogossypolone induces reactive oxygen species accumulation and controls cell cycle progression in Raji Burkkit’s lymphoma cells. Mol Med Rep 2012; 12:337-44. [DOI: 10.3892/mmr.2015.3404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Accepted: 02/05/2015] [Indexed: 11/05/2022] Open
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Ramakrishnan V, Timm M, Haug JL, Kimlinger TK, Halling T, Wellik LE, Witzig TE, Rajkumar SV, Adjei AA, Kumar S. Sorafenib, a multikinase inhibitor, is effective in vitro against non-Hodgkin lymphoma and synergizes with the mTOR inhibitor rapamycin. Am J Hematol 2012; 87:277-83. [PMID: 22190165 DOI: 10.1002/ajh.22263] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 11/15/2011] [Accepted: 11/18/2011] [Indexed: 12/11/2022]
Abstract
Non-Hodgkin lymphoma (NHL) represents a heterogenous group of neoplasias originating from lymphoid cells. Increased angiogenesis and expression of Vascular Endothelial Growth Factor (VEGF) and its receptors (VEGFR) have been found to be associated with NHL disease progression. Increase in VEGF and other cytokines stimulate signaling cascades, including the Ras/Raf/Mek/Erk pathway, resulting in increased proliferation and decreased apoptosis. Here, we report the in vitro antilymphoma activity of sorafenib, an inhibitor of VEGFR and Raf kinase. Sorafenib induced potent cytotoxicity in NHL cell lines and patient samples. This induction of cytotoxicity was associated with a corresponding increase in apoptotic cell death. Mechanism of action of sorafenib was investigated in follicular (DoHH2) and Burkitt lymphoma (Raji) cell lines. pStat3, pAkt, Mcl1, and Xiap were downregulated in both cell lines, whereas pErk decreased in Raji but not in DoHH2 cells following sorafenib treatment. IL6 was unable to prevent sorafenib induced repression of pStat3, pAkt, Mcl1, and Bcl-Xl. Sorafenib in combination with an mTORC1 inhibitor rapamycin demonstrated synergy in inducing cytotoxicity in NHL cells. Sorafenib/rapamycin combination resulted in downregulation of pAkt, pmTOR, p-p70S6K, p4EBP1, pGSK3β, Mcl1, and Bcl-Xl. On the basis of our results, a clinical trial is underway using sorafenib with everolimus in NHL patients.
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63
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Frappier L. The Epstein-Barr Virus EBNA1 Protein. SCIENTIFICA 2012; 2012:438204. [PMID: 24278697 PMCID: PMC3820569 DOI: 10.6064/2012/438204] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Accepted: 11/28/2012] [Indexed: 05/06/2023]
Abstract
Epstein-Barr virus (EBV) is a widespread human herpes virus that immortalizes cells as part of its latent infection and is a causative agent in the development of several types of lymphomas and carcinomas. Replication and stable persistence of the EBV genomes in latent infection require the viral EBNA1 protein, which binds specific DNA sequences in the viral DNA. While the roles of EBNA1 were initially thought to be limited to effects on the viral genomes, more recently EBNA1 has been found to have multiple effects on cellular proteins and pathways that may also be important for viral persistence. In addition, a role for EBNA1 in lytic infection has been recently identified. The multiple roles of EBNA1 in EBV infection are the subject of this paper.
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Affiliation(s)
- Lori Frappier
- Department of Molecular Genetics, University of Toronto, 1 Kings College Circle, Toronto, ON, Canada M5S 1A8
- *Lori Frappier:
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64
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Affiliation(s)
- Yoon-Jae Song
- Department of Life Science, Kyungwon University, Seongnam-Si, Kyeonggi-Do, Korea
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65
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Role of EBNA1 in NPC tumourigenesis. Semin Cancer Biol 2011; 22:154-61. [PMID: 22206863 DOI: 10.1016/j.semcancer.2011.12.002] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 11/29/2011] [Accepted: 12/09/2011] [Indexed: 12/12/2022]
Abstract
EBNA1 is expressed in all NPC tumours and is the only Epstein-Barr virus protein needed for the stable persistence of EBV episomes. EBNA1 binds to specific sequences in the EBV genome to facilitate the initiation of DNA synthesis, ensure the even distribution of the viral episomes to daughter cells during mitosis and to activate the transcription of other viral latency genes important for cell immortalization. In addition, EBNA1 has been found to alter cellular pathways in multiple ways that likely contribute to cell immortalization and malignant transformation. This chapter discusses the known functions and cellular effects of EBNA1, especially as pertains to NPC.
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Gargouri B, Nasr R, ben Mansour R, Lassoued S, Mseddi M, Attia H, El Feki AEF, Van Pelt J. Reactive oxygen species production and antioxidant enzyme expression after Epstein-Barr virus lytic cycle induction in Raji cell line. Biol Trace Elem Res 2011; 144:1449-57. [PMID: 21792596 DOI: 10.1007/s12011-011-9135-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 06/29/2011] [Indexed: 12/12/2022]
Abstract
In a previous study, we have described oxidative stress during Epstein-Barr virus lytic cycle induction. Oxidative stress was evidenced by the observed high MDA levels and the decreased activities of antioxidant enzymes. We hypothesised that the lower activities of the antioxidant enzymes decrease were the result of either the excessive production of reactive oxygen radical species (ROS) or a negative regulation of the antioxidant enzyme gene expressions. In an attempt to clarify this situation, EBV lytic cycle was induced in Raji cell line by a non-stressing dose of 12-0-tetradecanoylphorbol-13-acetate. BZLF-1, superoxide dismutase, and catalase gene expressions were then analysed using semi-quantitative RT-PCR, simultaneously at a kinetic of 6, 12, 24, 36, and 48 h. ROS production was evaluated by chemiluminescence. A study was conducted to establish whether ROS production, BZLF-1, and the expression of antioxidant genes were inter-correlated. Induction of the lytic cycle resulted in increased expressions of the genes of superoxide dismutase and catalase, which began at 24 h (p < 0.05) and reached a peak at 48 h (p < 0.05). Significant increases of the ROS levels were observed in TPA-treated Raji cell line at 12 h, as compared with untreated cells, reaching a peak at 48 h after EBV lytic cycle induction. ROS production correlates positively with BZLF-1, SOD, and CAT gene expressions (p < 0.05; r = 0.913, r = 0.978, and r = 0.955, respectively). A positive correlation was also observed between BZLF-1 and antioxidant gene expressions (p < 0.05; r = 0.961 and r = 0.987, respectively). In conclusion, the observed increases of the SOD and CAT gene expressions eliminate the hypothesis of a repression of the respective genes during the induction of the lytic cycle. On the other hand, the observed direct correlation between the BZLF-1 gene expression and the ROS production is indicative of a role of this gene in oxidative stress.
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Affiliation(s)
- Bochra Gargouri
- Unité de Biotechnologie et Pathologies, Institut Supérieur de Biotechnologie de Sfax, Sfax, Tunisia.
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Changes in the nasopharyngeal carcinoma nuclear proteome induced by the EBNA1 protein of Epstein-Barr virus reveal potential roles for EBNA1 in metastasis and oxidative stress responses. J Virol 2011; 86:382-94. [PMID: 22013061 DOI: 10.1128/jvi.05648-11] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Epstein-Barr virus (EBV) infection is causatively associated with a variety of human cancers, including nasopharyngeal carcinoma (NPC). The only viral nuclear protein expressed in NPC is EBNA1, which can alter cellular properties in ways that may promote oncogenesis. Here, we used 2-dimensional difference gel electrophoresis (2-D DiGE) to profile changes in the nuclear proteome that occur after stable expression of EBNA1 in the EBV-negative NPC cell line CNE2. We found that EBNA1 consistently altered the levels of a small percentage of the nuclear proteins. The identification of 19 of these proteins by mass spectrometry revealed that EBNA1 upregulated three proteins affecting metastatic potential (stathmin 1, maspin, and Nm23-H1) and several proteins in the oxidative stress response pathway, including the antioxidants superoxide dismutase 1 (SOD1) and peroxiredoxin 1 (Prx1). Western blot analysis verified that EBNA1 expression upregulated and EBNA1 silencing downregulated these proteins. In addition, transcripts for stathmin 1 were induced by EBNA1, whereas EBNA1 only affected Prx1 and SOD1 at the protein level. Further investigation of the EBNA1 effects on the redox pathway showed that long-term EBNA1 expression in NPC resulted in increased reactive oxygen species (ROS) and increased levels of the NADPH oxidases NOX1 and NOX2, known to generate ROS. In addition, EBNA1 depletion in EBV-positive cells decreased NOX2 and ROS. The results show multiple roles for EBNA1 in the oxidative stress response pathway and suggest mechanisms by which EBNA1 may promote NPC metastases.
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Tung WH, Hsieh HL, Lee IT, Yang CM. Enterovirus 71 induces integrin β1/EGFR-Rac1-dependent oxidative stress in SK-N-SH cells: Role of HO-1/CO in viral replication. J Cell Physiol 2011; 226:3316-29. [DOI: 10.1002/jcp.22677] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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69
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Gargouri B, Nasr R, Mseddi M, Benmansour R, Lassoued S. Induction of Epstein-Barr virus (EBV) lytic cycle in vitro causes lipid peroxidation, protein oxidation and DNA damage in lymphoblastoid B cell lines. Lipids Health Dis 2011; 10:111. [PMID: 21722381 PMCID: PMC3146848 DOI: 10.1186/1476-511x-10-111] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Accepted: 07/01/2011] [Indexed: 12/15/2022] Open
Abstract
Background We investigated the oxidative modifications of lipids, proteins and DNA, potential molecular targets of oxidative stress, in two lymphoblastoid cell lines: B95-8 and Raji, after EBV lytic cycle induction. Conjugated dienes level was measured as biomarker of lipid peroxidation. Malondialdehyde adduct and protein carbonyl levels, as well as protein thiol levels were measured as biomarkers of protein oxidation. DNA fragmentation was evaluated as biomarker of DNA oxidation. Results After 48 h (peak of lytic cycle), a significant increase in conjugated dienes level was observed in B95-8 and Raji cell lines (p = 0.0001 and p = 0.019 respectively). Malondialdehyde adduct, protein carbonyl levels were increased in B95-8 and Raji cell lines after EBV lytic cycle induction as compared to controls (MDA-adduct: p = 0.008 and p = 0.006 respectively; Carbonyl: p = 0.003 and p = 0.0039 respectively). Proteins thiol levels were decreased by induction in B95-8 and Raji cell lines (p = 0.046; p = 0.002 respectively). DNA fragmentation was also detected in B95-8 and Raji cell lines after EBV lytic cycle induction as compared to controls. Conclusion The results of this study demonstrate the presence of increased combined oxidative modifications in lipids, proteins in B95-8 and Raji cells lines after EBV lytic cycle induction. These results suggest that lipid peroxidation, protein oxidation and DNA fragmentation are generally induced during EBV lytic cycle induction and probably contribute to the cytopathic effect of EBV.
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Affiliation(s)
- Bochra Gargouri
- Unité de Biotechnologie et Pathologies, Institut Supérieur de Biotechnologie de Sfax, Tunisia.
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Romer EJ, Sulentic CEW. Hydrogen peroxide modulates immunoglobulin expression by targeting the 3'Igh regulatory region through an NFκB-dependent mechanism. Free Radic Res 2011; 45:796-809. [PMID: 21599461 DOI: 10.3109/10715762.2011.581280] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Reactive oxygen species such as hydrogen peroxide (H(2)O(2)) appear to play a role in signal transduction in immune cells and have been shown to be synthesized upon antigen-mediated activation and to facilitate cellular activation in B- and T-cells. However, an effect of H(2)O(2) on B-cell function (i.e. immunoglobulin (Ig) expression) has been less well-characterized. The effects of H(2)O(2) exposure on lymphocytes may be partly mediated by oxidative modulation of the NFκB signal transduction pathway, which also plays a role in Ig heavy chain (Igh) gene expression. Igh transcription in B lymphocytes is an essential step in antibody production and is governed through a complex interaction of several regulatory elements, including the 3'Igh regulatory region (3'IghRR). Utilizing an in vitro mouse B-cell line model, this study demonstrates that exposure to low μM concentrations of H(2)O(2) can enhance 3'IghRR-regulated transcriptional activity and Igh gene expression, while either higher concentrations of H(2)O(2) or the expression of a degradation resistant inhibitory κB (IκBα super-repressor) can abrogate this effect. Furthermore, suppressive H(2)O(2) concentrations increased protein levels of the p50 NFκB sub-unit, IκBα, and an IκBα immunoreactive band which was previously characterized as an IκBα cleavage product exhibiting stronger inhibitory function than native IκBα. Taken together, these observations suggest that exposure of B lymphocytes to H(2)O(2) can alter Igh transcriptional activity and Ig expression in a complex biphasic manner which appears to be mediated by NFκB and altered 3'IghRR activity. These results may have significant implications to disease states previously associated with the 3'IghRR.
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Affiliation(s)
- Eric J Romer
- Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, Ohio 45435, USA
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71
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Tung WH, Tsai HW, Lee IT, Hsieh HL, Chen WJ, Chen YL, Yang CM. Japanese encephalitis virus induces matrix metalloproteinase-9 in rat brain astrocytes via NF-κB signalling dependent on MAPKs and reactive oxygen species. Br J Pharmacol 2011; 161:1566-83. [PMID: 20698853 DOI: 10.1111/j.1476-5381.2010.00982.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Japanese encephalitis virus (JEV) is a member of the family Flaviviridae and JEV infection is a major cause of acute encephalopathy in children, which destroys cells in the CNS, including astrocytes and neurons. However, the detailed mechanisms underlying the inflammatory action of JEV are largely unclear. EXPERIMENTAL APPROACH The effect of JEV on the expression of matrix metalloproteinase (MMP)-9 was determined by gelatin zymography, Western blot analysis, real-time PCR and promoter assay. The involvement of the NADPH oxidase and reactive oxygen species (ROS), MAPKs, and the transcription factor NF-κB in these responses was investigated by using selective pharmacological inhibitors and transfection with appropriate siRNAs. KEY RESULTS JEV induced the expression of the pro-form of MMP-9 in rat brain astrocytes (RBA-1 cells). In RBA-1 cells, JEV induced MMP-9 expression and promoter activity, which was inhibited by pretreatment with inhibitors of NADPH oxidase (diphenylene iodonium chloride or apocynin), MAPKs (U0126, SB203580 or SP600125) and a ROS scavenger (N-acetylcysteine), or transfection with siRNAs of p47(phox) , ERK1, JNK2 and p38. In addition, JEV-induced MMP-9 expression was reduced by pretreatment with an inhibitor of NF-κB (helenalin) or transfection with p65 siRNA. Moreover, JEV-stimulated NF-κB activation was inhibited by pretreatment with the inhibitors of NADPH oxidase and MAPKs. CONCLUSIONS AND IMPLICATIONS MMP-9 expression induced by JEV infection of RBA-1 cells was mediated through the generation of ROS and activation of p42/p44 MAPK, p38 MAPK and JNK1/2, leading to NF-κB activation.
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Affiliation(s)
- Wei-Hsuan Tung
- Department of Physiology and Pharmacology, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
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72
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Breccia M, Alimena G. NF-κB as a potential therapeutic target in myelodysplastic syndromes and acute myeloid leukemia. Expert Opin Ther Targets 2011; 14:1157-76. [PMID: 20858024 DOI: 10.1517/14728222.2010.522570] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
IMPORTANCE OF THE FIELD The inactive NF-κB-inhibitor of NF-κB (IκB) complex is activated by stimuli including pro-inflammatory cytokines, mitogens, growth factors and stress-inducing agents. The release of NF-κB facilitates its translocation to the nucleus, where it promotes cell survival by initiating transcription of genes encoding stress-response enzymes, cell-adhesion molecules, pro-inflammatory cytokines and anti-apoptotic proteins. NF-κB and associated regulatory factors (IκB kinase subunits and bcl-3) are implicated in hematological and solid tumour malignancies. NF-κB appears to be involved in cell proliferation control, apoptosis control, angiogenesis promotion and possibly regulation of diffusion of metastases. There are several reports that inhibition of NF-κB as a therapeutic target may have a role in tumour cell death or growth inhibition. AREA COVERED IN THIS REVIEW We review data about inhibition of NF-κB in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). We describe the molecular mechanisms underlying NF-κB deregulation in these haematological malignancies. WHAT THE READER WILL GAIN Constitutive activation of NF-κB in the nucleus has been reported in some varieties of MDS/AML. The in vitro and in vivo results of NF-κB inhibition in myeloid malignancies are highlighted. TAKE HOME MESSAGE NF-κB selective inhibitory drugs may be useful, either as single agents or associated with conventional chemotherapy.
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Affiliation(s)
- Massimo Breccia
- Sapienza University, Department of Human Biotechnologies and Hematology, Rome, Italy.
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73
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Huang M, Whang P, Chodaparambil JV, Pollyea DA, Kusler B, Xu L, Felsher DW, Mitchell BS. Reactive oxygen species regulate nucleostemin oligomerization and protein degradation. J Biol Chem 2011; 286:11035-46. [PMID: 21242306 DOI: 10.1074/jbc.m110.208470] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Nucleostemin (NS) is a nucleolar-nucleoplasmic shuttle protein that regulates cell proliferation, binds p53 and Mdm2, and is highly expressed in tumor cells. We have identified NS as a target of oxidative regulation in transformed hematopoietic cells. NS oligomerization occurs in HL-60 leukemic cells and Raji B lymphoblasts that express high levels of c-Myc and have high intrinsic levels of reactive oxygen species (ROS); reducing agents dissociate NS into monomers and dimers. Exposure of U2OS osteosarcoma cells with low levels of intrinsic ROS to hydrogen peroxide (H(2)O(2)) induces thiol-reversible disulfide bond-mediated oligomerization of NS. Increased exposure to H(2)O(2) impairs NS degradation, immobilizes the protein within the nucleolus, and results in detergent-insoluble NS. The regulation of NS by ROS was validated in a murine lymphoma tumor model in which c-Myc is overexpressed and in CD34+ cells from patients with chronic myelogenous leukemia in blast crisis. In both instances, increased ROS levels were associated with markedly increased expression of NS protein and thiol-reversible oligomerization. Site-directed mutagenesis of critical cysteine-containing regions of nucleostemin altered both its intracellular localization and its stability. MG132, a potent proteasome inhibitor and activator of ROS, markedly decreased degradation and increased nucleolar retention of NS mutants, whereas N-acetyl-L-cysteine largely prevented the effects of MG132. These results indicate that NS is a highly redox-sensitive protein. Increased intracellular ROS levels, such as those that result from oncogenic transformation in hematopoietic malignancies, regulate the ability of NS to oligomerize, prevent its degradation, and may alter its ability to regulate cell proliferation.
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Affiliation(s)
- Min Huang
- Department of Medicine, Divisions of Oncology and Hematology, Stanford University School of Medicine, Stanford, California 94305, USA
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74
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Watanabe S, Ohtsuka K, Sato S, Takenaka S. Discrimination of phosphorylated double stranded DNA by naphthalene diimide having zinc(II) dipicolylamine complexes. Bioorg Med Chem 2010; 19:1361-5. [PMID: 21237662 DOI: 10.1016/j.bmc.2010.10.056] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Accepted: 10/27/2010] [Indexed: 11/17/2022]
Abstract
Discrimination of phosphomonoesters and phosphodiesters of DNA was attempted with naphthalene diimide carrying two zinc-dipicolylamine (Dpa) units (1). The binding constant of 1 for a self-complementary octanucleotide was 1.3×10(6)M(-1), while the value for the phosphorylated counterpart was 4.8×10(6)M(-1). This fourfold increase in the binding constant seems to stem from higher affinity of the terminal monophosphate over the phosphodiesters of DNA as the fourth ligand for the metal in 1. Likewise, the binding constant of 1 for DNase I-treated calf thymus DNA (average size 200bp) was twice as large as that for untreated DNA (1kb), possibly because the terminal phosphate groups are five times abundant in the former. These findings provide a clue to developing a system where phosphomonoesters generated upon DNA nicking are discriminated specifically from intact phosphodiesters.
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Affiliation(s)
- Sadayoshi Watanabe
- Department of Applied Chemistry, Kyushu Institute of Technology, 1-1 Senesui-cho, Tobata-ku, Kitakyushu-shi, Fukuoka 804-8550, Japan
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75
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Lassoued S, Gargouri B, El Feki AEF, Attia H, Van Pelt J. Transcription of the Epstein-Barr virus lytic cycle activator BZLF-1 during oxidative stress induction. Biol Trace Elem Res 2010; 137:13-22. [PMID: 19898754 DOI: 10.1007/s12011-009-8555-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Accepted: 10/16/2009] [Indexed: 12/12/2022]
Abstract
While latent Epstein-Barr virus infection can be in vitro reactivated by various reagents such as 12-0-tetradecanoylphorbol-13-acetate and calcium ionophore, relatively little is known about in vivo physiological and biochemical factors implicated in this reactivation. Previous studies have described an association between oxidative stress and Epstein-Barr virus infection. In this present study, we investigated the effect of oxidative stress inductors: H2O2 and FeSO4 on reactivation of EBV through BZLF-1 gene expression. Oxidative stress was induced in Raji cell line with 0.2 mM H2O2 or with 0.1 mM FeSO4, and assessed by malondialdehyde level determination, as well as superoxide dismutase and catalase genes expression. Simultaneously, the expression of Epstein-Barr virus immediate-early gene BZLF-1 was analyzed by RT-PCR after 6, 12, 24, 36, and 48 h after H2O2 or FeSO4 treatment. Oxidative stress was evidenced in the Raji cell line by high MDA level as well as superoxide dismutase and catalase genes up-regulation. The transcripts of BZLF-1 were detected from 6 h after 30 min of H2O2 or FeSO4 treatment and maintained until 48 h. These results strongly suggest that oxidative stress contributes to the reactivation of EBV lytic cycle, through induction of BZLF-1 gene expression, a process that may play an important role in the pathogenesis of EBV-associated diseases.
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Affiliation(s)
- Saloua Lassoued
- Unité de Biotechnologie et Pathologies, Institut Supérieur de Biotechnologie de Sfax, Bochra Gargouri BP 31 Sidi Abbes, 3062, Sfax, Tunisia
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76
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Cloonan SM, Williams DC. The antidepressants maprotiline and fluoxetine induce Type II autophagic cell death in drug-resistant Burkitt's lymphoma. Int J Cancer 2010; 128:1712-23. [PMID: 20503272 DOI: 10.1002/ijc.25477] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Accepted: 05/12/2010] [Indexed: 12/15/2022]
Abstract
Resistance to chemotherapy is a major obstacle for the success of cancer therapy and is most commonly attributed to the inability of cancer cells to die by apoptosis, the archetypal programed cell death (PCD) response. The development of anticancer drugs that can overcome this resistance to apoptosis and induce other forms of cell death is therefore paramount for efficient cancer therapy. We report that the antidepressants maprotiline and fluoxetine induce autophagic PCD in the chemoresistant Burkitt's lymphoma (BL) cell line DG-75, which does not involve caspases, DNA fragmentation or PARP cleavage, but is associated with the development of cytoplasmic vacuoles, all consistent with an autophagic mode of PCD. Autophagic PCD was confirmed by transmission electron microscopy, upregulation of Beclin-I and the extent of PCD being reduced by the autophagic inhibitor 3-MA. In contrast, these compounds induced apoptotic PCD in the biopsy-like chemosensitive BL MUTU-I cell line. We provide evidence that the chemoresistant DG-75 cells do not express the proapoptotic Bcl-2 proteins Bax and Bak, show diminished levels of stored intracellular calcium and display shortened rod-like mitochondria, all of which are known to be associated with a defective "apoptotic" response in cancer cells. PCD in the two cell lines has different Ca(2+) responses to maprotiline and fluoxetine, which may also account for their differential PCD responses. Our study, therefore, supports a new mechanistic role for maprotiline and fluoxetine as novel proautophagic agents in the treatment of resistant BL, and thus an alternative therapeutic application for these compounds.
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Affiliation(s)
- Suzanne M Cloonan
- School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
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77
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Nihal M, Roelke CT, Wood GS. Anti-melanoma effects of vorinostat in combination with polyphenolic antioxidant (-)-epigallocatechin-3-gallate (EGCG). Pharm Res 2010; 27:1103-14. [PMID: 20232120 DOI: 10.1007/s11095-010-0054-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Accepted: 01/05/2010] [Indexed: 01/15/2023]
Abstract
PURPOSE Melanoma is an aggressive neoplasm with a propensity for metastases and resistance to therapy. Previously, we showed that (-)-epigallocatechin-3-gallate (EGCG), the major polyphenolic antioxidant present in green tea, resulted in a significant decrease in the viability and growth of melanoma and induction of apoptosis via modulation of the cki-cdk-cyclin network and Bcl2 family proteins. Epigenetic regulation of gene transcription by histone deacetylase (HDAC) inhibitors is gaining momentum as a novel cancer therapy. SAHA-suberoylanilidine hydroxamic acid Zolinza (vorinostat) is the first HDAC inhibitor approved by the U.S. FDA. In this study, we determined if vorinostat alone or in combination with EGCG imparts anti-proliferative effects against human melanoma cells. METHODS Employing human melanoma cell lines A-375, Hs-294T and G-361, we determined the effect of vorinostat and/or EGCG on 1) growth/viability and colony formation, 2) apoptosis, and 3) the critical molecules involved in cell cycle and apoptosis regulation. RESULTS Our data demonstrated that the anti-proliferative effects of vorinostat were greater than or similar to those of EGCG among the cell lines tested. Furthermore, relative to monotherapy, the combination treatment resulted in significantly greater inhibition of cell proliferation, increased apoptosis, activation of p21, p27 and caspases (3, 7 and 9) and Bax as well as down-regulation of cdk2, cdk4, cyclin A, NF-kappaB protein p65/RelA and Bcl2 protein and transcript. CONCLUSIONS Our preclinical findings suggest that combination therapy with EGCG and vorinostat may be beneficial for the management of human melanoma.
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Affiliation(s)
- Minakshi Nihal
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, 1300 University Avenue, Room B25, Madison, Wisconsin 53706, USA
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78
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Reddy PVB, Lungu G, Kuang X, Stoica G, Wong PKY. Neuroprotective effects of the drug GVT (monosodium luminol) are mediated by the stabilization of Nrf2 in astrocytes. Neurochem Int 2010; 56:780-8. [PMID: 20211212 DOI: 10.1016/j.neuint.2010.02.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Revised: 02/19/2010] [Accepted: 02/28/2010] [Indexed: 12/19/2022]
Abstract
Oxidative stress is implicated in various kinds of neurological disorders, including human immunodeficiency virus (HIV) associated dementia (HAD). Our laboratory has been studying the murine retrovirus ts1, a pathogenic mutant of the Moloney murine leukemia virus (MoMuLV), as a model for HAD. Like HIV in humans, ts1 induces oxidative stress and progressive neurodegeneration in mice. We have shown previously that an antioxidant and anti-inflammatory drug GVT or MSL (monosodium luminol) suppresses ts1-induced oxidative stress, attenuates the development of spongiform encephalopathy, and delays hind limb paralysis in infected mice. It is known that upregulation of the nuclear transcription factor NF-E2-related factor 2 (Nrf2) is involved in upregulating cellular antioxidant defenses. Since Nrf2 is associated with elevation of antioxidant defenses in general, and since GVT suppresses ts1-induced neurodegeneration, our aim in this study was to determine whether GVT neuroprotection is linked to Nrf2 upregulation in the brain. We report here that GVT upregulates the levels of Nrf2, both in primary astrocyte cultures and in brainstem of ts1-infected mice. Significant upregulation of Nrf2 expression by GVT occurs in both the cytosolic and nuclear fractions of cultured astrocytes and brainstem cells. Notably, although GVT treatment increases Nrf2 protein levels in cultured astrocytes and brainstem tissues, Nrf2 mRNA levels are not altered. This suggests that the neuroprotective effects of GVT may be mediated by the stabilization of the Nrf2 protein, allowing continuous upregulation of Nrf2 levels in the astrocytes.
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Affiliation(s)
- Pichili Vijaya Bhaskar Reddy
- Department of Carcinogenesis, The University of Texas, MD Anderson Cancer Center, Science Park-Research Division, Smithville, TX 78957, USA
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79
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Lee HS, Lee MJ, Kim H, Choi SK, Kim JE, Moon HI, Park WH. Curcumin inhibits TNFα-induced lectin-like oxidised LDL receptor-1 (LOX-1) expression and suppresses the inflammatory response in human umbilical vein endothelial cells (HUVECs) by an antioxidant mechanism. J Enzyme Inhib Med Chem 2010; 25:720-9. [DOI: 10.3109/14756360903555274] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Hye-Sook Lee
- Cardiovascular Medical Research Center and Department of Diagnostics, College of Oriental Medicine, Dongguk University, Sukjang-Dong 707, Gyeong-Ju 780-714, Republic of Korea
| | - Min-Ja Lee
- Cardiovascular Medical Research Center and Department of Diagnostics, College of Oriental Medicine, Dongguk University, Sukjang-Dong 707, Gyeong-Ju 780-714, Republic of Korea
| | - Hyuck Kim
- Cardiovascular Medical Research Center and Department of Diagnostics, College of Oriental Medicine, Dongguk University, Sukjang-Dong 707, Gyeong-Ju 780-714, Republic of Korea
| | - Sung-Kyu Choi
- Cardiovascular Medical Research Center and Department of Diagnostics, College of Oriental Medicine, Dongguk University, Sukjang-Dong 707, Gyeong-Ju 780-714, Republic of Korea
| | - Jai-Eun Kim
- Cardiovascular Medical Research Center and Department of Diagnostics, College of Oriental Medicine, Dongguk University, Sukjang-Dong 707, Gyeong-Ju 780-714, Republic of Korea
| | - Hyung-In Moon
- Cardiovascular Medical Research Center and Department of Diagnostics, College of Oriental Medicine, Dongguk University, Sukjang-Dong 707, Gyeong-Ju 780-714, Republic of Korea
| | - Won-Hwan Park
- Cardiovascular Medical Research Center and Department of Diagnostics, College of Oriental Medicine, Dongguk University, Sukjang-Dong 707, Gyeong-Ju 780-714, Republic of Korea
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80
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Gargouri B, Lassoued S, Ayadi W, Karray H, Masmoudi H, Mokni N, Attia H, El Feki AEF. Lipid peroxidation and antioxidant system in the tumor and in the blood of patients with nasopharyngeal carcinoma. Biol Trace Elem Res 2009; 132:27-34. [PMID: 19436958 DOI: 10.1007/s12011-009-8384-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2009] [Accepted: 04/13/2009] [Indexed: 12/12/2022]
Abstract
Reactive oxygen species play a key role in cancer development by inducing and maintaining the oncogenic phenotypes of cancer cells. In this study, we examined lipid peroxidation and antioxidant enzymes activities in the blood and in the tumor of nasopharyngeal carcinoma patients. Plasma malondialdehyde, conjugated dienes, erythrocytes catalase, and superoxide dismutase activities have been measured in 30 untreated nasopharyngeal carcinoma patients and 30 controls on one hand. On the other hand, tumor malondialdehyde level, catalase, and superoxide dismutase activities have been measured in five nasopharyngeal carcinoma patients and compared with four controls. The lipid peroxidation was confirmed in the plasma by the high levels of malondialdehyde and conjugated dienes (p<0.001, respectively). Additionally, significantly higher concentrations of malondialdehyde were found in biopsies compared to the control group (p<0.001). In erythrocytes, superoxide dismutase activity was higher in patients than in controls (p<0.05), while it was unchanged in the tumor (p>0.05). Both erythrocytes and tumor catalase activities were significantly lower in patients than in controls (p<0.001, respectively). Statistical studies have shown a positive correlation between malondialdehyde level and IgA antibodies level against Epstein–Barr virus capsid antigen (p<0.05). In conclusion, we reported the presence of an oxidative stress in the blood and in the biopsies of nasopharyngeal carcinoma patients where Epstein–Barr virus seems to play a role.
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Affiliation(s)
- Bochra Gargouri
- Unité de Biotechnologie et Pathologies, Institut Supérieur de Biotechnologie de Sfax, BP 31 Sidi Abbes, 3062 Sfax, Tunisia.
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81
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Thompson CM, Grafström RC. Commentary: mechanistic considerations for associations between formaldehyde exposure and nasopharyngeal carcinoma. Environ Health 2009; 8:53. [PMID: 19939253 PMCID: PMC2788541 DOI: 10.1186/1476-069x-8-53] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Accepted: 11/25/2009] [Indexed: 05/05/2023]
Abstract
Occupational exposure to formaldehyde has been linked to nasopharyngeal carcinoma. To date, mechanistic explanations for this association have primarily focused on formaldehyde-induced cytotoxicity, regenerative hyperplasia and DNA damage. However, recent studies broaden the potential mechanisms as it is now well established that formaldehyde dehydrogenase, identical to S-nitrosoglutathione reductase, is an important mediator of cGMP-independent nitric oxide signaling pathways. We have previously described mechanisms by which formaldehyde can influence nitrosothiol homeostasis thereby leading to changes in pulmonary physiology. Considering evidences that nitrosothiols govern the Epstein-Barr virus infection cycle, and that the virus is strongly implicated in the etiology of nasopharyngeal carcinoma, studies are needed to examine the potential for formaldehyde to reactivate the Epstein-Barr virus as well as additively or synergistically interact with the virus to potentiate epithelial cell transformation.
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Affiliation(s)
- Chad M Thompson
- ToxStrategies, Inc, 23501 Cinco Ranch Blvd, Suite G265, Katy, TX 77494, USA
| | - Roland C Grafström
- Institute of Environmental Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden
- VTT Technical Research Centre of Finland, Medical Biotechnology, PO Box 106, FI-20521 Turku, Finland
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82
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Lacoste S, Wiechec E, Dos Santos Silva AG, Guffei A, Williams G, Lowbeer M, Benedek K, Henriksson M, Klein G, Mai S. Chromosomal rearrangements after ex vivo Epstein-Barr virus (EBV) infection of human B cells. Oncogene 2009; 29:503-15. [PMID: 19881539 DOI: 10.1038/onc.2009.359] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The Epstein-Barr virus (EBV) is carried by more than 90% of the adult world population and has been implicated in several human malignancies. Its ability to induce unlimited in vitro proliferation of B cells is frequently used to generate lymphoblastoid cell lines (LCLs). In this study, we have investigated the evolution of two LCLs up to 25 weeks after EBV infection. LCLs were karyotyped once a month by spectral karyotyping (SKY). LCLs but not mitogen-activated B cells showed evidence of DNA damage and DNA damage response within the first 2 weeks. After 4 weeks, the former, but not the latter, showed a high level of non-clonal structural aberrations, mainly deletions, fragments, dicentric chromosomes and unbalanced translocations. Genomic instability decreased thereafter over time. Nonrandom aneuploidy 12 weeks after infection showed clonal evolution in culture. After 25 weeks post-infection, most cells exhibited karyotypic stability. Chromosomal aberrations were compatible with telomere dysfunction, although in the absence of telomere shortening. The telomere capping protein TRF2 was partially displaced from telomeres in EBV-infected cells, suggesting an EBV-mediated uncapping problem. In conclusion, this study suggests that DNA damage and telomere dysfunction contribute to EBV-related chromosomal instability in early LCLs.
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Affiliation(s)
- S Lacoste
- Department of Physiology, Manitoba Institute of Cell Biology, University of Manitoba, Winnipeg, Manitoba, Canada R3E 0V9
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83
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Osipova-Goldberg HI, Turchanowa LV, Adler B, Pfeilschifter JM. H2O2 inhibits BCR-dependent immediate early induction of EBV genes in Burkitt's lymphoma cells. Free Radic Biol Med 2009; 47:1120-9. [PMID: 19540913 DOI: 10.1016/j.freeradbiomed.2009.06.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Revised: 05/22/2009] [Accepted: 06/16/2009] [Indexed: 11/30/2022]
Abstract
The critical step in the Epstein-Barr virus (EBV) transition from latency to lytic replication is activation of the viral immediate early (IE) genes, BZLF1 and BRLF1. Their induction in Burkitt's lymphoma Akata cells is directly targeted by B cell receptor (BCR) signaling. On the other hand, BCR stimulation causes an outwardly directed superoxide (O(2)(*-)) burst leading to massive generation of reactive oxygen species in the cell environment. Our goal was to investigate the role of BCR-related redox changes in the IE reactivation of EBV. Production of O(2)(*-) by stimulated Akata cells was characterized using chemiluminescent dyes, lucigenin, MCLA, and coelenterazine. Expression of the EBV IE genes was analyzed by real-time PCR and Western blot assays. Catalase activity and H(2)O(2) concentration were evaluated using Amplex Red assays and by measuring light absorption at 240 nm. We show here that elevation of H(2)O(2) concentration in Akata cell suspensions inhibits the induction of the virus IE mRNA and BZLF1 protein. It was further found that Akata cells exhibit catalase-like activity that is stimulated by BCR cross-linking. The results reveal that H(2)O(2) is instrumental in the maintenance of EBV latency. Altogether they provide new evidence demonstrating the essential role of H(2)O(2) in BCR signaling.
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84
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Reactive oxygen species and mitogen-activated protein kinase activation in the development of Burkitt's lymphoma in Crohn disease. J Clin Gastroenterol 2009; 43:598-9. [PMID: 19034040 DOI: 10.1097/mcg.0b013e3181734a41] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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85
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Affiliation(s)
- Levi E Fried
- Department of Dermatology, Emory University School of Medicine, WMB 5309, 101 Woodruff Circle Atlanta, GA 30322, USA
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86
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Matusali G, Arena G, De Leo A, Di Renzo L, Mattia E. Inhibition of p38 MAP kinase pathway induces apoptosis and prevents Epstein Barr virus reactivation in Raji cells exposed to lytic cycle inducing compounds. Mol Cancer 2009; 8:18. [PMID: 19272151 PMCID: PMC2657105 DOI: 10.1186/1476-4598-8-18] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Accepted: 03/09/2009] [Indexed: 12/15/2022] Open
Abstract
Background EBV lytic cycle activators, such as phorbol esters, anti-immunoglobulin, transforming growth factor β (TGFβ), sodium butyrate, induce apoptosis in EBV-negative but not in EBV-positive Burkitt's lymphoma (BL) cells. To investigate the molecular mechanisms allowing EBV-infected cells to be protected, we examined the expression of viral and cellular antiapoptotic proteins as well as the activation of signal transduction pathways in BL-derived Raji cells exposed to lytic cycle inducing agents. Results Our data show that, following EBV activation, the latent membrane protein 1 (LMP1) and the cellular anti-apoptotic proteins MCL-1 and BCL-2 were quickly up-regulated and that Raji cells remained viable even when exposed simultaneously to P(BU)2, sodium butyrate and TGFβ. We report here that inhibition of p38 pathway, during EBV activation, led to a three fold increment of apoptosis and largely prevented lytic gene expression. Conclusion These findings indicate that, during the switch from the latent to the lytic phase of EBV infection, p38 MAPK phosphorylation plays a key role both for protecting the host cells from apoptosis as well as for inducing viral reactivation. Because Raji cells are defective for late antigens expression, we hypothesize that the increment of LMP1 gene expression in the early phases of EBV lytic cycle might contribute to the survival of the EBV-positive cells.
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Affiliation(s)
- Giulia Matusali
- Department of Public Health Sciences, University La Sapienza, Rome, Italy.
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87
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Signalling of the BCR is regulated by a lipid rafts-localised transcription factor, Bright. EMBO J 2009; 28:711-24. [PMID: 19214191 DOI: 10.1038/emboj.2009.20] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Accepted: 01/09/2009] [Indexed: 02/06/2023] Open
Abstract
Regulation of BCR signalling strength is crucial for B-cell development and function. Bright is a B-cell-restricted factor that complexes with Bruton's tyrosine kinase (Btk) and its substrate, transcription initiation factor-I (TFII-I), to activate immunoglobulin heavy chain gene transcription in the nucleus. Here we show that a palmitoylated pool of Bright is diverted to lipid rafts of resting B cells where it associates with signalosome components. After BCR ligation, Bright transiently interacts with sumoylation enzymes, blocks calcium flux and phosphorylation of Btk and TFII-I and is then discharged from lipid rafts as a Sumo-I-modified form. The resulting lipid raft concentration of Bright contributes to the signalling threshold of B cells, as their sensitivity to BCR stimulation decreases as the levels of Bright increase. Bright regulates signalling independent of its role in IgH transcription, as shown by specific dominant-negative titration of rafts-specific forms. This study identifies a BCR tuning mechanism in lipid rafts that is regulated by differential post-translational modification of a transcription factor with implications for B-cell tolerance and autoimmunity.
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88
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Samper E, Morgado L, Estrada JC, Bernad A, Hubbard A, Cadenas S, Melov S. Increase in mitochondrial biogenesis, oxidative stress, and glycolysis in murine lymphomas. Free Radic Biol Med 2009; 46:387-96. [PMID: 19038329 PMCID: PMC2665299 DOI: 10.1016/j.freeradbiomed.2008.10.036] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Revised: 09/05/2008] [Accepted: 10/13/2008] [Indexed: 11/24/2022]
Abstract
Lymphomas adapt to their environment by undergoing a complex series of biochemical changes that are currently not well understood. To better define these changes, we examined the gene expression and gene ontology profiles of thymic lymphomas from a commonly used model of carcinogenesis, the p53(-/-) mouse. These tumors show a highly significant upregulation of mitochondrial biogenesis, mitochondrial protein translation, mtDNA copy number, reactive oxygen species, antioxidant defenses, proton transport, ATP synthesis, hypoxia response, and glycolysis, indicating a fundamental change in the bioenergetic profile of the transformed T cell. Our results suggest that T cell tumorigenesis involves a simultaneous upregulation of mitochondrial biogenesis, mitochondrial respiration, and glycolytic activity. These processes would allow cells to adapt to the stressful tumor environment by facilitating energy production and thereby promote tumor growth. Understanding these adaptations is likely to result in improved therapeutic strategies for this tumor type.
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Affiliation(s)
- Enrique Samper
- The Buck Institute for Age Research, Novato, CA 94945, USA.
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89
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The Epstein-Barr virus nuclear antigen-1 promotes genomic instability via induction of reactive oxygen species. Proc Natl Acad Sci U S A 2009; 106:2313-8. [PMID: 19139406 DOI: 10.1073/pnas.0810619106] [Citation(s) in RCA: 174] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The Epstein-Barr virus (EBV) nuclear antigen (EBNA)-1 is the only viral protein expressed in all EBV-carrying malignancies, but its contribution to oncogenesis has remained enigmatic. We show that EBNA-1 induces chromosomal aberrations, DNA double-strand breaks, and engagement of the DNA damage response (DDR). These signs of genomic instability are associated with the production of reactive oxygen species (ROS) and are reversed by antioxidants. The catalytic subunit of the leukocyte NADPH oxidase, NOX2/gp91(phox), is transcriptionally activated in EBNA-1-expressing cells, whereas inactivation of the enzyme by chemical inhibitors or RNAi halts ROS production and DDR. These findings highlight a novel function of EBNA-1 and a possible mechanism by which expression of this viral protein could contribute to malignant transformation and tumor progression.
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90
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Epstein-Barr virus in cutaneous T-cell lymphomas: evaluation of the viral presence and significance in skin and peripheral blood. J Invest Dermatol 2009; 129:1556-61. [PMID: 19131945 DOI: 10.1038/jid.2008.396] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The importance of viral agents in the development of cutaneous T-cell lymphomas (CTCL) is still debated. For this purpose, we retrospectively evaluated the Epstein-Barr virus (EBV) presence in Sézary syndrome (SS), mycosis fungoides (MF), inflammatory dermatoses (ID), and healthy donors (HD) using different approaches: EBV-DNA was quantified in skin biopsies and peripheral blood using real-time PCR, EBV-encoded small RNA (EBER) transcripts were detected by in situ hybridization (ISH), and latent membrane protein1-2 antigens were detected by immunohistochemistry. Skin biopsies were EBV-DNA-positive in 8/30 (27%) SS, 7/71 (10%) MF, and 2/18 (11%) ID patients and in none of the 25 normal skin samples. Positive mRNA (EBER) signals, always confined to cerebriform T lymphocytes, were found in 5/30 SS patients (17%), whereas signals in all MF and ID patients were negative. The presence of EBV-DNA in skin and blood samples was associated with a significantly lower survival in MF/SS patients. In evaluating EBV serological status, most (>70%) SS, MF, and ID patients showed a serological reactivation demonstrated by the presence of anti-EA IgG. In conclusion, although the finding of EBV-DNA in CTCL does not prove its etiopathogenetic role and may be related instead to immunosuppression, our study demonstrates that it has prognostic relevance.
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91
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Gargouri B, Van Pelt J, El Feki AEF, Attia H, Lassoued S. Induction of Epstein-Barr virus (EBV) lytic cycle in vitro causes oxidative stress in lymphoblastoid B cell lines. Mol Cell Biochem 2008; 324:55-63. [PMID: 19082543 DOI: 10.1007/s11010-008-9984-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Accepted: 12/01/2008] [Indexed: 12/11/2022]
Abstract
Here, we investigated the effect of induction of the Epstein-Barr virus (EBV) viral lytic cycle on the oxidant/antioxidant balance in three lymphoblastoid cell lines: B95-8, Raji, and LCL C1. The induction of the EBV lytic cycle was done by a non-stressing dose of 12-0-tetradecanoylphorbol-13-acetate (8 nM). Oxidative stress was assessed by measuring malondialdehyde as a parameter of lipid peroxidation, the levels of glutathione, and the activities of three antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase). After 48 h (peak of lytic cycle), a significant decrease in superoxide dismutase activity was observed in B95-8, Raji, and LCL C1 cells (P < 0.05). In addition, in B95-8 cells also a significant decrease of catalase activity was detected (P < 0.05). The glutathione peroxidase activity and the glutathione level were not significantly modified by the induction in any of the cell lines. We found a significant rise in malondialdehyde levels in B95-8, Raji, and LCL C1 cells after the induction of the lytic cycle compared to controls (P < 0.05). In conclusion, induction of EBV lytic cycle in lymphoblastoid cells causes increased oxidative stress in the host cells within 48 h, a process that could be involved in malignant transformations.
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Affiliation(s)
- Bochra Gargouri
- Unité de Biotechnologie et Pathologies, Institut Supérieur de Biotechnologie de Sfax, Sfax, Tunisia.
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92
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Le Poole C, Denman CJ, Arbiser JL. Immunosuppression may be present within condyloma acuminata. J Am Acad Dermatol 2008; 59:967-74. [DOI: 10.1016/j.jaad.2008.08.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Revised: 08/05/2008] [Accepted: 08/11/2008] [Indexed: 02/07/2023]
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93
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Bhandarkar SS, Bromberg J, Carrillo C, Selvakumar P, Sharma RK, Perry BN, Govindarajan B, Fried L, Sohn A, Reddy K, Arbiser JL. Tris (dibenzylideneacetone) dipalladium, a N-myristoyltransferase-1 inhibitor, is effective against melanoma growth in vitro and in vivo. Clin Cancer Res 2008; 14:5743-8. [PMID: 18794083 DOI: 10.1158/1078-0432.ccr-08-0405] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
PURPOSE Melanoma is a solid tumor that is notoriously resistant to chemotherapy, and its incidence is rapidly increasing. Recently, several signaling pathways have been shown to contribute to melanoma tumorigenesis, including constitutive activation of mitogen-activated protein kinase, Akt, and Stat-3. The activation of multiple pathways may account in part for the difficulty in treatment of melanoma. In a recent screen of compounds, we found that an organopalladium compound, Tris (dibenzylideneacetone) dipalladium (Tris DBA), showed significant antiproliferative activity against melanoma cells. Studies were carried out to determine the mechanism of action of Tris DBA. EXPERIMENTAL DESIGN Tris DBA was tested on efficacy on proliferation of human and murine melanoma cells. To find the mechanism of action of Tris DBA, we did Western blot and gene array analyses. The ability of Tris DBA to block tumor growth in vivo was assessed. RESULTS Tris DBA has activity against B16 murine and A375 human melanoma in vivo. Tris DBA inhibits several signaling pathways including activation of mitogen-activated protein kinase, Akt, Stat-3, and S6 kinase activation, suggesting an upstream target. Tris DBA was found to be a potent inhibitor of N-myristoyltransferase-1, which is required for optimal activity of membrane-based signaling molecules. Tris DBA showed potent antitumor activity in vivo against melanoma. CONCLUSION Tris DBA is thus a novel inhibitor of N-myristoyltransferase-1 with significant antitumor activity and is well tolerated in vivo. Further preclinical evaluation of Tris DBA and related complexes is warranted.
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94
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Effect of proton beam on blood vessel formation in early developing zebrafish (Danio rerio) embryos. Arch Pharm Res 2008; 31:779-85. [PMID: 18563361 DOI: 10.1007/s12272-001-1226-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 04/13/2008] [Accepted: 05/08/2008] [Indexed: 10/21/2022]
Abstract
Proton beam therapy can kill tumor cells while saving normal cells because of its specific energy delivery properties and so is used to various tumor patients. However, the effect of proton beam on angiogenesis in the development of blood vessels has not been determined. Here we used the zebrafish model to determine in vivo whether proton beam inhibits angiogenesis. Flk-1-GFP transgenic embryos irradiated with protons (35 MeV, spread out Bragg peak, SOBP) demonstrated a marked inhibition of embryonic growth and an altered fluorescent blood vessel development in the trunk region. When cells were stained with acridine orange to evaluate DNA damage, the number of green fluorescent cell death spots was increased in trunk regions of irradiated embryos compared to non-irradiated control embryos. Proton beam also significantly increased the cell death rate in human umbilical vein endothelial cells (HUVEC), but pretreatment with N-acetyl cystein (NAC), an antioxidant, reduced the proton-induced cell death rate (p<0.01). Moreover, pretreatment with NAC abrogated the inhibition of trunk vessel development and prevented the trunk malformation caused by proton irradiation. In conclusion, proton irradiation significantly inhibited in vivo vascular development possibly due to increased vascular cell death via reactive oxygen species formation.
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95
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Wu YH, Tseng CP, Cheng ML, Ho HY, Shih SR, Chiu DTY. Glucose-6-phosphate dehydrogenase deficiency enhances human coronavirus 229E infection. J Infect Dis 2008; 197:812-6. [PMID: 18269318 PMCID: PMC7199897 DOI: 10.1086/528377] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The host cellular environment is a key determinant of pathogen infectivity. Viral gene expression and viral particle production of glucose-6-phosphate dehydrogenase (G6PD)–deficient and G6PD-knockdown cells were much higher than their counterparts when human coronavirus (HCoV) 229E was applied at 0.1 multiplicity of infection. These phenomena were correlated with increased oxidant production. Accordingly, ectopic expression of G6PD in G6PD-deficient cells or addition of antioxidant (such as α-lipoic acid) to G6PD-knockdown cells attenuated the increased susceptibility to HCoV 229E infection. All experimental data indicated that oxidative stress in host cells is an important factor in HCoV 229E infectivity
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Affiliation(s)
- Yi-Hsuan Wu
- Graduate Institute of Basic Medical Sciences, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan
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96
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Molecular basis of cytotoxicity of Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) in EBV latency III B cells: LMP1 induces type II ligand-independent autoactivation of CD95/Fas with caspase 8-mediated apoptosis. J Virol 2008; 82:6721-33. [PMID: 18448526 DOI: 10.1128/jvi.02250-07] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The Epstein-Barr virus (EBV) oncoprotein latent membrane protein 1 (LMP1) is thought to act as the major transforming protein in various cell types, by rerouting the tumor necrosis factor receptor family signaling pathway. Despite this implication in EBV-associated transformation of cells, LMP1 toxicity is a well-known but poorly studied feature, perhaps because it contradicts its role in transformation. We show that LMP1 physiological levels are very heterogeneous and that the highest levels of LMP1 correlate with Fas overexpression and spontaneous apoptosis in lymphoblastoid cell lines (LCLs). To understand the cytotoxic effect of LMP1 in LCLs, we cloned wild-type LMP1 into a doxycycline double-inducible episomal vector pRT-1, with a truncated version of NGFR as a surrogate marker of inducibility. We found that LMP1 overexpression induced apoptosis in LCL B cells, as shown by annexin V labeling, sub-G(1) peak, and poly(ADP ribose) polymerase cleavage. Knocking down Fas expression by small interfering RNA abolished LMP1-induced apoptosis. The absence of detectable levels of Fas ligand mRNA suggested a ligand-independent activation of Fas. LMP1 induced Fas overexpression with its relocalization in lipid raft microdomains of the membrane. Fas immunoprecipitation detected FADD (Fas-associated death domain protein) and caspase 8, suggesting a Fas-dependent formation of the death-inducing signaling complex. Caspases 8, 9, 3, and 7 were activated by LMP1. Caspase 8 activation was associated with BID cleavage and truncated-BID mitochondrial relocalization, consistent with type II apoptosis. Therefore, our results are in agreement with a model where LMP1-dependent NF-kappaB activation induces Fas overexpression and autoactivation that could overwhelm the antiapoptotic effect of NF-kappaB, revealing an ambivalent function of LMP1 in cell survival and programmed cell death.
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97
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Epstein-Barr virus induces an oxidative stress during the early stages of infection in B lymphocytes, epithelial, and lymphoblastoid cell lines. Mol Cell Biochem 2008; 313:179-86. [DOI: 10.1007/s11010-008-9755-z] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2008] [Accepted: 03/28/2008] [Indexed: 01/12/2023]
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98
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Bhandarkar SS, MacKelfresh J, Fried L, Arbiser JL. Targeted therapy of oral hairy leukoplakia with gentian violet. J Am Acad Dermatol 2008; 58:711-2. [PMID: 18342722 DOI: 10.1016/j.jaad.2007.11.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Revised: 10/30/2007] [Accepted: 11/15/2007] [Indexed: 12/11/2022]
Abstract
Oral hairy leukoplakia (OHL) is a common oral manifestation of HIV infection. Clinically, these lesions appear as white plaques on the edges of the tongue. Pathophysiologically, these lesions occur because of infection of oral epithelium with Epstein-Barr virus (EBV). No universally effective therapy exists for OHL. We have previously shown that EBV infection and EBV viral products induce the generation of reactive oxygen. We have also demonstrated that the Food and Drug Administration-approved over-the-counter medication gentian violet is a potent inhibitor of reactive oxygen species. We thus chose to treat a patient with biopsy-proven OHL with topical gentian violet. Gentian violet solution was applied topically to the tongue of a patient with OHL. Complete clinical resolution was noted after three treatments. Treatment with topical gentian violet resulted in resolution of the lesions. Further studies with larger numbers of patients are required. The application of gentian violet can be used as a method to OHL treatment. Gentian violet is an inexpensive and safe therapy and, given that it inhibits reactive oxygen, this old therapy is now a targeted novel therapy.
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Affiliation(s)
- Sulochana S Bhandarkar
- Department of Dermatology, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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99
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Abstract
In melanoma, at least four major signaling abnormalities have been described. They include beta-catenin deregulation (mutation/mislocalization), p16 loss, MAP kinase activation, and Akt activation. In this review, we discuss the role of the fourth pathway, known as the reactive oxygen driven tumor. The role of reactive oxygen in tumorigenesis is likely to relate to virtually all forms of cancer, and lends itself to specific therapies. These include blockade of reactive oxygen, resulting in decreased activation of NF-kappaB, which should sensitize tumors to chemotherapy and radiation. The phenotype of the reactive oxygen driven tumor can be monitored using available markers already in use in most hospital laboratories.
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Affiliation(s)
- Levi Fried
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
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100
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Chen M, Chen ZQ, Cui PG, Yao X, Li YM, Li AS, Gong JQ, Cao YH. The methylation pattern of p16INK4a gene promoter in psoriatic epidermis and its clinical significance. Br J Dermatol 2008; 158:987-93. [PMID: 18373711 DOI: 10.1111/j.1365-2133.2008.08505.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Alteration of the p16INK4a gene by epigenetic changes has been described in some hyperproliferative skin diseases, but its importance in psoriasis has not yet been established. OBJECTIVES To investigate the methylation status of the p16INK4a gene in psoriatic epidermis, its clinical significance and the possible epigenetic mechanisms of psoriasis. METHODS DNA and RNA specimens were obtained from the lesional epidermis of 56 patients with plaque psoriasis. Methylation-specific polymerase chain reaction (PCR) and DNA sequencing were used to detect the density and sites of methylation in the p16INK4a promoter region. The reverse transcription-PCR technique was applied to detect the mRNA expression of p16INK4a. RESULTS p16INK4a gene promoter methylation was shown in 17 of 56 (30%) patients with psoriasis. Psoriasis Area and Severity Index scores in patients showing methylation were higher than in those who did not (P<0.05). The mRNA expression level of p16INK4a in the methylated group was significantly lower than in the unmethylated group (t=2.515, P=0.015). In the methylated group, about 50% of the CpG islands were methylated in the promoter region. CONCLUSIONS Overall, methylation of the p16INK4a gene promoter is found in psoriatic epidermis, which is associated with the mRNA level of p16INK4a expression and activity of the disease. These data indicate that methylation of the p16INK4a promoter may play a potential role in the pathogenesis of psoriasis.
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Affiliation(s)
- M Chen
- Department of Clinical Dermatology and Immunology, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, Nanjing, China.
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