1
|
Willman GH, Xu H, Zeigler TM, McIntosh MT, Bhaduri-McIntosh S. Polymerase theta is a synthetic lethal target for killing Epstein-Barr virus lymphomas. J Virol 2024; 98:e0057224. [PMID: 38860782 PMCID: PMC11265443 DOI: 10.1128/jvi.00572-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 05/27/2024] [Indexed: 06/12/2024] Open
Abstract
Treatment options for Epstein-Barr virus (EBV)-cancers are limited, underscoring the need for new therapeutic approaches. We have previously shown that EBV-transformed cells and cancers lack homologous recombination (HR) repair, a prominent error-free pathway that repairs double-stranded DNA breaks; instead, EBV-transformed cells demonstrate genome-wide scars of the error-prone microhomology-mediated end joining (MMEJ) repair pathway. This suggests that EBV-cancers are vulnerable to synthetic lethal therapeutic approaches that target MMEJ repair. Indeed, we have previously found that targeting PARP, an enzyme that contributes to MMEJ, results in the death of EBV-lymphoma cells. With the emergence of clinical resistance to PARP inhibitors and the recent discovery of inhibitors of Polymerase theta (POLθ), the polymerase essential for MMEJ, we investigated the role of POLθ in EBV-lymphoma cells. We report that EBV-transformed cell lines, EBV-lymphoma cell lines, and EBV-lymphomas in AIDS patients demonstrate greater abundance of POLθ, driven by the EBV protein EBNA1, compared to EBV-uninfected primary lymphocytes and EBV-negative lymphomas from AIDS patients (a group that also abundantly expresses POLθ). We also find POLθ enriched at cellular DNA replication forks and exposure to the POLθ inhibitor Novobiocin impedes replication fork progress, impairs MMEJ-mediated repair of DNA double-stranded breaks, and kills EBV-lymphoma cells. Notably, cell killing is not due to Novobiocin-induced activation of the lytic/replicative phase of EBV. These findings support a role for POLθ not just in DNA repair but also DNA replication and as a therapeutic target in EBV-lymphomas and potentially other EBV-cancers as EBNA1 is expressed in all EBV-cancers.IMPORTANCEEpstein-Barr virus (EBV) contributes to ~2% of the global cancer burden. With a recent estimate of >200,000 deaths a year, identifying molecular vulnerabilities will be key to the management of these frequently aggressive and treatment-resistant cancers. Building on our earlier work demonstrating reliance of EBV-cancers on microhomology-mediated end-joining repair, we now report that EBV lymphomas and transformed B cell lines abundantly express the MMEJ enzyme POLθ that likely protects cellular replication forks and repairs replication-related cellular DNA breaks. Importantly also, we show that a newly identified POLθ inhibitor kills EBV-cancer cells, revealing a novel strategy to block DNA replication and repair of these aggressive cancers.
Collapse
Affiliation(s)
- Griffin H. Willman
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
| | - Huanzhou Xu
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
| | - Travis M. Zeigler
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
| | - Michael T. McIntosh
- Child Health Research Institute, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, Florida, USA
| | - Sumita Bhaduri-McIntosh
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, Florida, USA
| |
Collapse
|
2
|
Studstill CJ, Mac M, Moody CA. Interplay between the DNA damage response and the life cycle of DNA tumor viruses. Tumour Virus Res 2023; 16:200272. [PMID: 37918513 PMCID: PMC10685005 DOI: 10.1016/j.tvr.2023.200272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/26/2023] [Accepted: 10/29/2023] [Indexed: 11/04/2023] Open
Abstract
Approximately 20 % of human cancers are associated with virus infection. DNA tumor viruses can induce tumor formation in host cells by disrupting the cell's DNA replication and repair mechanisms. Specifically, these viruses interfere with the host cell's DNA damage response (DDR), which is a complex network of signaling pathways that is essential for maintaining the integrity of the genome. DNA tumor viruses can disrupt these pathways by expressing oncoproteins that mimic or inhibit various DDR components, thereby promoting genomic instability and tumorigenesis. Recent studies have highlighted the molecular mechanisms by which DNA tumor viruses interact with DDR components, as well as the ways in which these interactions contribute to viral replication and tumorigenesis. Understanding the interplay between DNA tumor viruses and the DDR pathway is critical for developing effective strategies to prevent and treat virally associated cancers. In this review, we discuss the current state of knowledge regarding the mechanisms by which human papillomavirus (HPV), merkel cell polyomavirus (MCPyV), Kaposi's sarcoma-associated herpesvirus (KSHV), and Epstein-Barr virus (EBV) interfere with DDR pathways to facilitate their respective life cycles, and the consequences of such interference on genomic stability and cancer development.
Collapse
Affiliation(s)
- Caleb J Studstill
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States
| | - Michelle Mac
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States
| | - Cary A Moody
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States.
| |
Collapse
|
3
|
Owens SM, Sifford JM, Li G, Murdock SJ, Salinas E, Manzano M, Ghosh D, Stumhofer JS, Forrest JC. Intrinsic p53 Activation Restricts Gammaherpesvirus-Driven Germinal Center B Cell Expansion during Latency Establishment. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.31.563188. [PMID: 37961505 PMCID: PMC10634957 DOI: 10.1101/2023.10.31.563188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Gammaherpesviruses (GHV) are DNA tumor viruses that establish lifelong latent infections in lymphocytes. For viruses such as Epstein-Barr virus (EBV) and murine gammaherpesvirus 68 (MHV68), this is accomplished through a viral gene-expression program that promotes cellular proliferation and differentiation, especially of germinal center (GC) B cells. Intrinsic host mechanisms that control virus-driven cellular expansion are incompletely defined. Using a small-animal model of GHV pathogenesis, we demonstrate in vivo that tumor suppressor p53 is activated specifically in B cells that are latently infected by MHV68. In the absence of p53, the early expansion of MHV68 latency was greatly increased, especially in GC B cells, a cell-type whose proliferation was conversely restricted by p53. We identify the B cell-specific latency gene M2, a viral promoter of GC B cell differentiation, as a viral protein sufficient to elicit a p53-dependent anti-proliferative response caused by Src-family kinase activation. We further demonstrate that EBV-encoded latent membrane protein 1 (LMP1) similarly triggers a p53 response in primary B cells. Our data highlight a model in which GHV latency gene-expression programs that promote B cell proliferation and differentiation to facilitate viral colonization of the host trigger aberrant cellular proliferation that is controlled by p53. IMPORTANCE Gammaherpesviruses cause lifelong infections of their hosts, commonly referred to as latency, that can lead to cancer. Latency establishment benefits from the functions of viral proteins that augment and amplify B cell activation, proliferation, and differentiation signals. In uninfected cells, off-schedule cellular differentiation would typically trigger anti-proliferative responses by effector proteins known as tumor suppressors. However, tumor suppressor responses to gammaherpesvirus manipulation of cellular processes remain understudied, especially those that occur during latency establishment in a living organism. Here we identify p53, a tumor suppressor commonly mutated in cancer, as a host factor that limits virus-driven B cell proliferation and differentiation, and thus, viral colonization of a host. We demonstrate that p53 activation occurs in response to viral latency proteins that induce B cell activation. This work informs a gap in our understanding of intrinsic cellular defense mechanisms that restrict lifelong GHV infection.
Collapse
|
4
|
Baccianti F, Masson C, Delecluse S, Li Z, Poirey R, Delecluse HJ. Epstein-Barr virus infectious particles initiate B cell transformation and modulate cytokine response. mBio 2023; 14:e0178423. [PMID: 37830871 PMCID: PMC10653912 DOI: 10.1128/mbio.01784-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 08/14/2023] [Indexed: 10/14/2023] Open
Abstract
IMPORTANCE The Epstein-Barr virus efficiently infects and transforms B lymphocytes. During this process, infectious viral particles transport the viral genome to the nucleus of target cells. We show here that these complex viral structures serve additional crucial roles by activating transcription of the transforming genes encoded by the virus. We show that components of the infectious particle sequentially activate proinflammatory B lymphocyte signaling pathways that, in turn, activate viral gene expression but also cause cytokine release. However, virus infection activates expression of ZFP36L1, an RNA-binding stress protein that limits the length and the intensity of the cytokine response. Thus, the infectious particles can activate viral gene expression and initiate cellular transformation at the price of a limited immune response.
Collapse
Affiliation(s)
- Francesco Baccianti
- Pathogenesis of Virus Associated Tumors, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Unit U1074, INSERM, Heidelberg, Germany
| | - Charlène Masson
- Pathogenesis of Virus Associated Tumors, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Unit U1074, INSERM, Heidelberg, Germany
| | - Susanne Delecluse
- Pathogenesis of Virus Associated Tumors, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Unit U1074, INSERM, Heidelberg, Germany
- Nierenzentrum Heidelberg e.V., Heidelberg, Germany
- Deutsches Zentrum für Infektionsforschung (DZIF), Braunschweig, Germany
| | - Zhe Li
- Pathogenesis of Virus Associated Tumors, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Unit U1074, INSERM, Heidelberg, Germany
| | - Remy Poirey
- Pathogenesis of Virus Associated Tumors, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Unit U1074, INSERM, Heidelberg, Germany
| | - Henri-Jacques Delecluse
- Pathogenesis of Virus Associated Tumors, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Unit U1074, INSERM, Heidelberg, Germany
| |
Collapse
|
5
|
Li L, Hu X, Nkwocha J, Sharma K, Kmieciak M, Mann H, Zhou L, Grant S. Non-canonical role for the ataxia-telangiectasia-Rad3 pathway in STAT3 activation in human multiple myeloma cells. Cell Oncol (Dordr) 2023; 46:1369-1380. [PMID: 37126127 PMCID: PMC10618375 DOI: 10.1007/s13402-023-00817-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2023] [Indexed: 05/02/2023] Open
Abstract
PURPOSE The goal of this study was to characterize the relationship between ATR and STAT3 interactions in human multiple myeloma (MM) cells. METHODS Various MM cell lines, including IL-6-dependent cells were exposed to ATR inhibitors and effects on STAT3 Tyr705 and Ser727 were monitored by WB analysis and ImageStream analysis. Parallel studies examined induction of cell death, STAT3 DNA binding activity, and expression of STAT3 downstream targets (BCL-XL, MCL-1, c-MYC). Validation was obtained in ATR shRNA knock-down cells, and in cells ectopically expressing BCL-XL, MCL-1, or c-MYC. Analogous studies were performed in primary MM cells and in a MM xenograft model. RESULTS Multiple pharmacologic ATR inhibitors inhibited STAT3 Tyr705 (but not Ser727) phosphorylation at low uM concentrations and down-regulated BCL-XL, MCL-1, c-MYC in association with cell death induction. Compatible results were observed in ATR shRNA knock-down cells. Cell death induced by ATR inhibitors was significantly attenuated in cells ectopically expressing constitutively active STAT3, BCL-XL, MCL-1, or c-MYC. Concordant results were observed in primary human MM cells and in an in vivo MM xenograft model. CONCLUSIONS Collectively, these findings argue for a non-canonical role for the ATR kinase in STAT3 activation in MM cells, and suggest that STAT3 inactivation contributes to the lethal actions of ATR inhibitors in MM.
Collapse
Affiliation(s)
- Lin Li
- Division of Hematology/Oncology, Department of Medicine, Virginia Commonwealth University, P.O. Box 980035, Richmond, VA, 23298, USA
| | - Xiaoyan Hu
- Division of Hematology/Oncology, Department of Medicine, Virginia Commonwealth University, P.O. Box 980035, Richmond, VA, 23298, USA
| | - Jewel Nkwocha
- Division of Hematology/Oncology, Department of Medicine, Virginia Commonwealth University, P.O. Box 980035, Richmond, VA, 23298, USA
| | - Kanika Sharma
- Division of Hematology/Oncology, Department of Medicine, Virginia Commonwealth University, P.O. Box 980035, Richmond, VA, 23298, USA
| | - Maciej Kmieciak
- Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA
| | - Hashim Mann
- Division of Hematology/Oncology, Department of Medicine, Virginia Commonwealth University, P.O. Box 980035, Richmond, VA, 23298, USA
| | - Liang Zhou
- Division of Hematology/Oncology, Department of Medicine, Virginia Commonwealth University, P.O. Box 980035, Richmond, VA, 23298, USA
- Department of Translational Medicine, Asklepios BioPharmaceutical, Inc., Durham, NC, USA
| | - Steven Grant
- Division of Hematology/Oncology, Department of Medicine, Virginia Commonwealth University, P.O. Box 980035, Richmond, VA, 23298, USA.
- Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA.
| |
Collapse
|
6
|
Xu Y, Li J, Zhu K, Zeng Y, Chen J, Dong X, Zhang S, Xu S, Wu G. FIBP interacts with transcription factor STAT3 to induce EME1 expression and drive radioresistance in lung adenocarcinoma. Int J Biol Sci 2023; 19:3816-3829. [PMID: 37564211 PMCID: PMC10411469 DOI: 10.7150/ijbs.83134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 07/08/2023] [Indexed: 08/12/2023] Open
Abstract
Cancer cells inevitably develop radioresistance during lung adenocarcinoma radiotherapy. However, the mechanisms are incompletely clarified. In this study, we show that FIBP protein expression in lung adenocarcinoma tissues is upregulated and associated with worse overall survival. Functionally, we find that depletion of FIBP inhibits lung adenocarcinoma progression and radioresistance in vitro and in vivo. Moreover, we uncover that FIBP interacts with STAT3 to enhance its transcriptional activity, thereby inducing the expression of the downstream target gene EME1. Importantly, we demonstrate that the biological effects of FIBP are partially dependent on EME1 in lung adenocarcinoma. Our work reveals that FIBP modulates the STAT3/EME1 axis to drive lung cancer progression and radioresistance, indicating that targeting FIBP may be a novel intervention strategy for lung adenocarcinoma radiotherapy.
Collapse
Affiliation(s)
- Yunhong Xu
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jun Li
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Kuikui Zhu
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yulan Zeng
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jing Chen
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xiaorong Dong
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Sheng Zhang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Shuangbing Xu
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Gang Wu
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| |
Collapse
|
7
|
Zhuang H, Li F, Xu Y, Pei R, Chen D, Liu X, Li S, Ye P, Yuan J, Lian J, Lu Y. Loss of IRF8 inhibits the growth of acute myeloid leukemia cells. Ann Hematol 2023; 102:1063-1072. [PMID: 36959484 DOI: 10.1007/s00277-023-05156-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 02/28/2023] [Indexed: 03/25/2023]
Abstract
The transcription factor interferon regulatory factor 8 (IRF8), as a member of the IRF family, is essential for myeloid cell differentiation. However, the precise role of IRF8 in the pathogenesis of acute myeloid leukemia (AML) remains unknown. By using multivariate analysis, we discovered that high IRF8 expression was an independent poor predictor of overall survival (OS) in AML patients from our clinical follow-up study. The proliferation of three AML cell lines was significantly inhibited by shRNA-mediated knockdown of IRF8, owing to cell cycle S-phase arrest. Furthermore, we demonstrated that knocking down IRF8 could suppress the expression of CyclinA and CyclinB1, resulting in a shift in cell cycle distribution. Loss of IRF8 in AML cells decreased the expression of STAT3 and phosphor-STAT3 (pSTAT3), which are key factors in JAK/STAT signal pathway and are important for AML progression. Using a xenograft mouse model, we discovered the antiproliferative effect of losing IRF8 in vivo. In conclusion, this study found that IRF8 may play a prognostic factor and therapeutic target in AML.
Collapse
Affiliation(s)
- Haihui Zhuang
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Fenglin Li
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Yulian Xu
- College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Renzhi Pei
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Dong Chen
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Xuhui Liu
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Shuangyue Li
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Peipei Ye
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Jiaojiao Yuan
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Jiaying Lian
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China
| | - Ying Lu
- Department of Hematology, The Affiliated People's Hospital of Ningbo University, Ningbo, China.
- Institute of Hematology, Ningbo University, Baizhang Road 251#, Ningbo, China.
| |
Collapse
|
8
|
Galectin-9 Facilitates Epstein-Barr Virus Latent Infection and Lymphomagenesis in Human B Cells. Microbiol Spectr 2023; 11:e0493222. [PMID: 36622166 PMCID: PMC9927364 DOI: 10.1128/spectrum.04932-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The immune regulator galectin-9 (Gal-9) is commonly involved in the regulation of cell proliferation, but with various impacts depending on the cell type. Here, we revealed that Gal-9 expression was persistently increased in Epstein-Barr virus (EBV)-infected primary B cells from the stage of early infection to the stage of mature lymphoblastoid cell lines (LCLs). This sustained upregulation paralleled that of gene sets related to cell proliferation, such as oxidative phosphorylation, cell cycle activation, and DNA replication. Knocking down or blocking Gal-9 expression obstructed the establishment of latent infection and outgrowth of EBV-infected B cells, while exogenous Gal-9 protein promoted EBV acute and latent infection and outgrowth of EBV-infected B cells at the early infection stage. Mechanically, stimulator of interferon gene (STING) activation or signal transducer and activator of transcription 3 (STAT3) inhibition impeded the outgrowth of EBV-infected B cells and promotion of Gal-9-induced lymphoblastoid cell line (LCL) transformation. Accordingly, Gal-9 expression was upregulated by forced EBV nuclear antigen 1 (EBNA1) expression in 293T cells in vitro. Clinical data showed that Gal-9 expression in B-cell lymphomas (BCLs) correlated positively with EBNA1 and disease stage. Targeting Gal-9 slowed LCL tumor growth and metastasis in xenografted immunodeficient mice. These findings highlight an oncogenic role of Gal-9 in EBV-associated BCLs, indicating that Gal-9 boosts the transformation of EBV-infected B cells. IMPORTANCE The cross talk between Epstein-Barr virus (EBV) and the host cell transcriptome assumes important roles in the oncogenesis of EBV-associated malignancies. Here, we first observed that endogenous Gal-9 expression was persistently increased along with an overturned V-type change in antivirus signaling during the immortalization of EBV-transformed B cells. Upregulation of Gal-9 promoted the outgrowth and latent infection of EBV-infected B cells, which was linked to B-cell-origin tumors by suppressing STING signaling and subsequently promoting STAT3 phosphorylation. EBV nuclear antigen EBNA1 induced Gal-9 expression and formed a positive feedback loop with Gal-9 in EBV-infected B cells. Tumor Gal-9 levels were positively correlated with disease stage and EBNA1 expression in patients with B-cell lymphomas (BCLs). Targeting Gal-9 slowed the growth and metastases of LCL tumors in immunodeficient mice. Altogether, our findings indicate that Gal-9 is involved in the lymphomagenesis of EBV-positive BCLs through cross talk with EBNA1 and STING signals.
Collapse
|
9
|
Jung SY, Park JI, Jeong JH, Song KH, Ahn J, Hwang SG, Kim J, Park JK, Lim DS, Song JY. Receptor interacting protein 1 knockdown induces cell death in liver cancer by suppressing STAT3/ATR activation in a p53-dependent manner. Am J Cancer Res 2022; 12:2594-2611. [PMID: 35812053 PMCID: PMC9251686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023] Open
Abstract
The survival and death of eukaryotic cells are tightly controlled by a variety of proteins in response to the cellular environment. Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) is a receptor-interacting Ser/Thr kinase that has recently been reported as an important regulator of cell survival, apoptosis, and necroptosis; however, its role in liver cancer remains unclear. In this study, we examined the effect of siRNA-mediated RIPK1 knockdown on the survival and death of liver cancer cells. Treatment with siRIPK1 decreased the growth rate of liver cancer cells and increased apoptotic, but not necrotic cell death, which was higher in wild-type p53 (wt-p53) cells than in mutant-type p53 (mt-p53) cells. In addition, RIPK1 knockdown increased p53 expression and G1 phase arrest in wt-p53 cells. Although suppressing p53 did not alter RIPK1 expression, it did attenuate siRIPK1-induced cell death. Interestingly, RIPK1 knockdown also increased the generation of reactive oxygen species and DNA damage by inhibiting signal transduced and activator of transcription 3 (STAT3) and ATM and RAD3-related (ATR) in wt-p53 cells but not in mt-p53 cells. Moreover, STAT3 or ATR inhibition in p53 mutant cells restored siRIPK1-mediated cell death. Together, the results of this study suggest that RIPK1 suppression induces apoptotic cell death by inhibiting the STAT3/ATR axis in a p53-dependent manner. Furthermore, these findings suggest that RIPK1, alone or in combination, may be a promising target for treating liver cancer.
Collapse
Affiliation(s)
- Seung-Youn Jung
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| | - Jeong-In Park
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| | - Jae-Hoon Jeong
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| | - Kyung-Hee Song
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| | - Jiyeon Ahn
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| | - Sang-Gu Hwang
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| | - Jaesung Kim
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| | - Jong-Kuk Park
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| | - Dae-Seog Lim
- Department of Biotechnology, CHA UniversityGyeonggi-do 13488, Republic of Korea
| | - Jie-Young Song
- Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical SciencesSeoul 01812, Republic of Korea
| |
Collapse
|
10
|
Jacob M, Masood A, Shinwari Z, Abdel Jabbar M, Al-Mousa H, Arnaout R, AlSaud B, Dasouki M, Alaiya AA, Abdel Rahman AM. Proteomics Profiling to Distinguish DOCK8 Deficiency From Atopic Dermatitis. FRONTIERS IN ALLERGY 2021; 2:774902. [PMID: 35386989 PMCID: PMC8974780 DOI: 10.3389/falgy.2021.774902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/22/2021] [Indexed: 11/13/2022] Open
Abstract
Dedicator of cytokinesis 8 deficiency is an autosomal recessive primary immune deficiency disease belonging to the group of hyperimmunoglobulinemia E syndrome (HIES). The clinical phenotype of dedicator of cytokinesis 8 (DOCK8) deficiency, characterized by allergic manifestations, increased infections, and increased IgE levels, overlaps with the clinical presentation of atopic dermatitis (AD). Despite the identification of metabolomics and cytokine biomarkers, distinguishing between the two conditions remains clinically challenging. The present study used a label-free untargeted proteomics approach using liquid-chromatography mass spectrometry with network pathway analysis to identify the differentially regulated serum proteins and the associated metabolic pathways altered between the groups. Serum samples from DOCK8 (n = 10), AD (n = 9) patients and healthy control (Ctrl) groups (n = 5) were analyzed. Based on the proteomics profile, the PLS-DA score plot between the three groups showed a clear group separation and sample clustering (R2 = 0.957, Q2 = 0.732). Significantly differentially abundant proteins (p < 0.05, FC cut off 2) were identified between DOCK8-deficient and AD groups relative to Ctrl (n = 105, and n = 109) and between DOCK8-deficient and AD groups (n = 85). Venn diagram analysis revealed a differential regulation of 24 distinct proteins from among the 85 between DOCK8-deficient and AD groups, including claspin, haptoglobin-related protein, immunoglobulins, complement proteins, fibulin, and others. Receiver-operating characteristic curve (ROC) analysis identified claspin and haptoglobin-related protein, as potential biomarkers with the highest sensitivity and specificity (AUC = 1), capable of distinguishing between patients with DOCK8 deficiency and AD. Network pathway analysis between DOCK8-deficiency and AD groups revealed that the identified proteins centered around the dysregulation of ERK1/2 signaling pathway. Herein, proteomic profiling of DOCK8-deficiency and AD groups was carried out to determine alterations in the proteomic profiles and identify a panel of the potential proteomics biomarker with possible diagnostic applications. Distinguishing between DOCK8-deficiency and AD will help in the early initiation of treatment and preventing complications.
Collapse
Affiliation(s)
- Minnie Jacob
- Metabolomics Section, Department of Clinical Genomics, Center for Genomics Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Afshan Masood
- Proteomics Resource Unit, Obesity Research Center, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Zakiya Shinwari
- Proteomics Unit, Stem-Cell and Tissue Re-engineering Program, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Mai Abdel Jabbar
- Metabolomics Section, Department of Clinical Genomics, Center for Genomics Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Hamoud Al-Mousa
- Section of Pediatric Allergy and Immunology, Department of Pediatrics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Rand Arnaout
- Section of Pediatric Allergy and Immunology, Department of Pediatrics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Bandar AlSaud
- Section of Pediatric Allergy and Immunology, Department of Pediatrics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Majed Dasouki
- Metabolomics Section, Department of Clinical Genomics, Center for Genomics Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Ayodele A. Alaiya
- Proteomics Unit, Stem-Cell and Tissue Re-engineering Program, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Anas M. Abdel Rahman
- Metabolomics Section, Department of Clinical Genomics, Center for Genomics Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
- Department of Chemistry, Memorial University of Newfoundland, St. John's, NL, Canada
- *Correspondence: Anas M. Abdel Rahman
| |
Collapse
|
11
|
The Epstein-Barr Virus Oncogene EBNA1 Suppresses Natural Killer Cell Responses and Apoptosis Early after Infection of Peripheral B Cells. mBio 2021; 12:e0224321. [PMID: 34781735 PMCID: PMC8593684 DOI: 10.1128/mbio.02243-21] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The innate immune system serves as frontline defense against pathogens, such as bacteria and viruses. Natural killer (NK) cells are a part of innate immunity and can both secrete cytokines and directly target cells for lysis. NK cells express several cell surface receptors, including NKG2D, which bind multiple ligands. People with deficiencies in NK cells are often susceptible to uncontrolled infection by herpesviruses, such as Epstein-Barr virus (EBV). Infection with EBV stimulates both innate and adaptive immunity, yet the virus establishes lifelong latent infection in memory B cells. We show that the EBV oncogene EBNA1, previously known to be necessary for maintaining EBV genomes in latently infected cells, also plays an important role in suppressing NK cell responses and cell death in newly infected cells. EBNA1 does so by downregulating the NKG2D ligands ULBP1 and ULBP5 and modulating expression of c-Myc. B cells infected with a derivative of EBV that lacks EBNA1 are more susceptible to NK cell-mediated killing and show increased levels of apoptosis. Thus, EBNA1 performs a previously unappreciated role in reducing immune response and programmed cell death after EBV infection, helping infected cells avoid immune surveillance and apoptosis and thus persist for the lifetime of the host. IMPORTANCE Epstein-Barr virus (EBV) is a ubiquitous human pathogen, infecting up to 95% of the world's adult population. Initial infection with EBV can cause infectious mononucleosis. EBV is also linked to several human malignancies, including lymphomas and carcinomas. Although infection by EBV alerts the immune system and causes an immune response, the virus persists for life in memory B cells. We show that the EBV protein EBNA1 can downregulate several components of the innate immune system linked to natural killer (NK) cells. This downregulation of NK cell activity translates to lower killing of EBV-infected cells and is likely one way that EBV escapes immune surveillance after infection. Additionally, we show that EBNA1 reduces apoptosis in newly infected B cells, allowing more of these cells to survive. Taken together, our findings uncover new functions of EBNA1 and provide insights into viral strategies to survive the initial immune response postinfection.
Collapse
|
12
|
Yao Y, Shen X, Zhou M, Tang B. Periodontal Pathogens Promote Oral Squamous Cell Carcinoma by Regulating ATR and NLRP3 Inflammasome. Front Oncol 2021; 11:722797. [PMID: 34660289 PMCID: PMC8514820 DOI: 10.3389/fonc.2021.722797] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 08/09/2021] [Indexed: 02/05/2023] Open
Abstract
Periodontitis is closely related to oral cancer, but the molecular mechanism of periodontal pathogens involved in the occurrence and development of oral cancer is still inconclusive. Here, we demonstrate that, in vitro, the cell proliferation ability and S phase cells of the periodontitis group (colonized by Porphyromonas gingivalis and Fusobacterium nucleatum, P+) significantly increased, but the G1 cells were obviously reduced. The animal models with an in situ oral squamous cell carcinoma (OSCC) and periodontitis-associated bacteria treatment were constructed, and micro-CT showed that the alveolar bone resorption of mice in the P+ group (75.3 ± 4.0 μm) increased by about 53% compared with that in the control group (48.8 ± 1.3 μm). The tumor mass and tumor growth rate in the P+ group were all higher than those in the blank control group. Hematoxylin-eosin (H&E) staining of isolated tumor tissues showed that large-scale flaky necrosis was found in the tumor tissue of the P+ group, with lots of damaged vascular profile and cell debris. Immunohistochemistry (IHC) of isolated tumor tissues showed that the expression of Ki67 and the positive rate of cyclin D1 were significantly higher in tumor tissues of the P+ group. The qRT-PCR results of the expression of inflammatory cytokines in oral cancer showed that periodontitis-associated bacteria significantly upregulated interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-18, apoptosis-associated speck-like protein containing a CARD (ASC) (up to six times), and caspase-1 (up to four times), but it downregulated nuclear factor (NF)-κB, NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3), and IL-1β (less than 0.5 times). In addition, the volume of spleen tissue and the number of CD4+ T cells, CD8+ T cells, and CD206+ macrophages in the P+ group increased significantly. IHC and Western blotting in tumor tissues showed that expression levels of γ-H2AX, p-ATR, RPA32, CHK1, and RAD51 were upregulated, and the phosphorylation level of CHK1 (p-chk1) was downregulated. Together, we identify that the periodontitis-related bacteria could promote tumor growth and proliferation, initiate the overexpressed NLRP3, and activate upstream signal molecules of ATR-CHK1. It is expected to develop a new molecular mechanism between periodontitis-related bacteria and OSCC.
Collapse
Affiliation(s)
- Yufei Yao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xin Shen
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Maolin Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Boyu Tang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| |
Collapse
|
13
|
Frey TR, Akinyemi IA, Burton EM, Bhaduri-McIntosh S, McIntosh MT. An Ancestral Retrovirus Envelope Protein Regulates Persistent Gammaherpesvirus Lifecycles. Front Microbiol 2021; 12:708404. [PMID: 34434177 PMCID: PMC8381357 DOI: 10.3389/fmicb.2021.708404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 07/14/2021] [Indexed: 11/13/2022] Open
Abstract
Human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) persist as life-long infections alternating between latency and lytic replication. Human endogenous retroviruses (HERVs), via integration into the host genome, represent genetic remnants of ancient retroviral infections. Both show similar epigenetic silencing while dormant, but can reactivate in response to cell signaling cues or triggers that, for gammaherpesviruses, result in productive lytic replication. Given their co-existence with humans and shared epigenetic silencing, we asked if HERV expression might be linked to lytic activation of human gammaherpesviruses. We found ERVW-1 mRNA, encoding the functional HERV-W envelope protein Syncytin-1, along with other repeat class elements, to be elevated upon lytic activation of EBV. Knockdown/knockout of ERVW-1 reduced lytic activation of EBV and KSHV in response to various lytic cycle triggers. In this regard, reduced expression of immediate early proteins ZEBRA and RTA for EBV and KSHV, respectively, places Syncytin-1's influence on lytic activation mechanistically upstream of the latent-to-lytic switch. Conversely, overexpression of Syncytin-1 enhanced lytic activation of EBV and KSHV in response to lytic triggers, though this was not sufficient to induce lytic activation in the absence of such triggers. Syncytin-1 is expressed in replicating B cell blasts and lymphoma-derived B cell lines where it appears to contribute to cell cycle progression. Together, human gammaherpesviruses and B cells appear to have adapted a dependency on Syncytin-1 that facilitates the ability of EBV and KSHV to activate lytic replication from latency, while promoting viral persistence during latency by contributing to B cell proliferation.
Collapse
Affiliation(s)
- Tiffany R. Frey
- Department of Pediatrics, Child Health Research Institute, University of Florida, Gainesville, FL, United States
| | - Ibukun A. Akinyemi
- Department of Pediatrics, Child Health Research Institute, University of Florida, Gainesville, FL, United States
| | - Eric M. Burton
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, FL, United States
| | - Sumita Bhaduri-McIntosh
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, FL, United States
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, United States
| | - Michael T. McIntosh
- Department of Pediatrics, Child Health Research Institute, University of Florida, Gainesville, FL, United States
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, United States
| |
Collapse
|
14
|
Du J, Jiang L, Chen F, Hu H, Zhou M. Cardiac Glycoside Ouabain Exerts Anticancer Activity via Downregulation of STAT3. Front Oncol 2021; 11:684316. [PMID: 34277430 PMCID: PMC8279743 DOI: 10.3389/fonc.2021.684316] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 06/16/2021] [Indexed: 12/30/2022] Open
Abstract
Cardiac glycosides are plant-derived steroid-like compounds which have been used for the treatment of cardiovascular diseases. Ouabain, a cardiotonic steroid and specific Na+/K+-ATPase inhibitor, has been rediscovered for its potential use in the treatment of cancer. However, the cellular targets and anticancer mechanism of ouabain in various cancers remain largely unexplored. In this study, we confirmed the cytotoxic effects of ouabain on several cancer cell lines. Further examination revealed the increase of apoptosis, intracellular ROS generation and DNA double-strand breaks induced by ouabain treatment. Besides, ouabain effectively suppressed STAT3 expression as well as phosphorylation in addition to block STAT3-mediated transcription and downstream target proteins. Interestingly, these inhibitory activities seemed to be independent of the Na+/K+-ATPase. Furthermore, we found that ouabain inhibited protein synthesis through regulation of the eukaryotic initiation factor 4E (eIF4E) and eIF4E binding protein 1 (4EBP1). Taken together, our study provided a novel molecular insight of anticancer activities of ouabain in human cancer cells, which could raise the hope of using cardiac glycosides for cancer therapeutics more rational.
Collapse
Affiliation(s)
- Jie Du
- Jiangmen Central Hospital, Affiliated Jiangmen Hospital of Sun Yat-sen University, Jiangmen, China.,Department of Radiation Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Lijun Jiang
- Department of Radiation Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Fuqiang Chen
- Department of Radiation Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Huantao Hu
- The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Meijuan Zhou
- Department of Radiation Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| |
Collapse
|
15
|
Pavan ICB, Peres de Oliveira A, Dias PRF, Basei FL, Issayama LK, Ferezin CDC, Silva FR, Rodrigues de Oliveira AL, Alves dos Reis Moura L, Martins MB, Simabuco FM, Kobarg J. On Broken Ne(c)ks and Broken DNA: The Role of Human NEKs in the DNA Damage Response. Cells 2021; 10:507. [PMID: 33673578 PMCID: PMC7997185 DOI: 10.3390/cells10030507] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/04/2021] [Accepted: 02/22/2021] [Indexed: 02/07/2023] Open
Abstract
NIMA-related kinases, or NEKs, are a family of Ser/Thr protein kinases involved in cell cycle and mitosis, centrosome disjunction, primary cilia functions, and DNA damage responses among other biological functional contexts in vertebrate cells. In human cells, there are 11 members, termed NEK1 to 11, and the research has mainly focused on exploring the more predominant roles of NEKs in mitosis regulation and cell cycle. A possible important role of NEKs in DNA damage response (DDR) first emerged for NEK1, but recent studies for most NEKs showed participation in DDR. A detailed analysis of the protein interactions, phosphorylation events, and studies of functional aspects of NEKs from the literature led us to propose a more general role of NEKs in DDR. In this review, we express that NEK1 is an activator of ataxia telangiectasia and Rad3-related (ATR), and its activation results in cell cycle arrest, guaranteeing DNA repair while activating specific repair pathways such as homology repair (HR) and DNA double-strand break (DSB) repair. For NEK2, 6, 8, 9, and 11, we found a role downstream of ATR and ataxia telangiectasia mutated (ATM) that results in cell cycle arrest, but details of possible activated repair pathways are still being investigated. NEK4 shows a connection to the regulation of the nonhomologous end-joining (NHEJ) repair of DNA DSBs, through recruitment of DNA-PK to DNA damage foci. NEK5 interacts with topoisomerase IIβ, and its knockdown results in the accumulation of damaged DNA. NEK7 has a regulatory role in the detection of oxidative damage to telomeric DNA. Finally, NEK10 has recently been shown to phosphorylate p53 at Y327, promoting cell cycle arrest after exposure to DNA damaging agents. In summary, this review highlights important discoveries of the ever-growing involvement of NEK kinases in the DDR pathways. A better understanding of these roles may open new diagnostic possibilities or pharmaceutical interventions regarding the chemo-sensitizing inhibition of NEKs in various forms of cancer and other diseases.
Collapse
Affiliation(s)
- Isadora Carolina Betim Pavan
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
| | - Andressa Peres de Oliveira
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
| | - Pedro Rafael Firmino Dias
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
| | - Fernanda Luisa Basei
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
| | - Luidy Kazuo Issayama
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
| | - Camila de Castro Ferezin
- Graduate Program in “Biologia Funcional e Molecular”, Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas 13083-857, Brazil;
| | - Fernando Riback Silva
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
| | - Ana Luisa Rodrigues de Oliveira
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
| | - Lívia Alves dos Reis Moura
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
| | - Mariana Bonjiorno Martins
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
- Graduate Program in “Biologia Funcional e Molecular”, Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas 13083-857, Brazil;
| | | | - Jörg Kobarg
- Graduate Program in “Ciências Farmacêuticas”, School of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, State University of Campinas (UNICAMP), R. Cândido Portinari 200, Prédio 2, Campinas CEP 13083-871, Brazil; (I.C.B.P.); (A.P.d.O.); (P.R.F.D.); (F.L.B.); (L.K.I.); (F.R.S.); (A.L.R.d.O.); (L.A.d.R.M.); (M.B.M.)
- Graduate Program in “Biologia Funcional e Molecular”, Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas 13083-857, Brazil;
| |
Collapse
|
16
|
Hanafi M, Chen X, Neamati N. Discovery of a Napabucasin PROTAC as an Effective Degrader of the E3 Ligase ZFP91. J Med Chem 2021; 64:1626-1648. [PMID: 33506674 DOI: 10.1021/acs.jmedchem.0c01897] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Napabucasin, undergoing multiple clinical trials, was reported to inhibit the signal transducer and transcription factor 3 (STAT3). To better elucidate its mechanism of action, we designed a napabucasin-based proteolysis targeting chimera (PROTAC), XD2-149 that resulted in inhibition of STAT3 signaling in pancreatic cancer cell lines without inducing proteasome-dependent degradation of STAT3. Proteomics analysis of XD2-149 revealed the downregulation of the E3 ubiquitin-protein ligase ZFP91. XD2-149 degrades ZFP91 with DC50 values in the nanomolar range. The cytotoxicity of XD2-149 was significantly, but not fully, reduced with ZFP91 knockdown providing evidence for its multi-targeted mechanism of action. The NQO1 inhibitor, dicoumarol, rescued the cytotoxicity of XD2-149 but not ZFP91 degradation, suggesting that the NQO1-induced cell death is independent of ZFP91. ZFP91 plays a role in tumorigenesis and is involved in multiple oncogenic pathways including NF-κB and HIF-1α.
Collapse
Affiliation(s)
- Maha Hanafi
- Department of Medicinal Chemistry, College of Pharmacy and the Rogel Cancer Center, North Campus Research Complex, 1600 Huron Parkway, University of Michigan, Ann Arbor, Michigan 48109, United States.,Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt
| | - Xinde Chen
- Department of Medicinal Chemistry, College of Pharmacy and the Rogel Cancer Center, North Campus Research Complex, 1600 Huron Parkway, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Nouri Neamati
- Department of Medicinal Chemistry, College of Pharmacy and the Rogel Cancer Center, North Campus Research Complex, 1600 Huron Parkway, University of Michigan, Ann Arbor, Michigan 48109, United States
| |
Collapse
|
17
|
McIntosh MT, Koganti S, Boatwright JL, Li X, Spadaro SV, Brantly AC, Ayers JB, Perez RD, Burton EM, Burgula S, MacCarthy T, Bhaduri-McIntosh S. STAT3 imparts BRCAness by impairing homologous recombination repair in Epstein-Barr virus-transformed B lymphocytes. PLoS Pathog 2020; 16:e1008849. [PMID: 33002095 PMCID: PMC7529304 DOI: 10.1371/journal.ppat.1008849] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 07/31/2020] [Indexed: 12/30/2022] Open
Abstract
Epstein-Barr virus (EBV) causes lymphomas and epithelial cell cancers. Though generally silent in B lymphocytes, this widely prevalent virus can cause endemic Burkitt lymphoma and post-transplant lymphoproliferative disorders/lymphomas in immunocompromised hosts. By learning how EBV breaches barriers to cell proliferation, we hope to undermine those strategies to treat EBV lymphomas and potentially other cancers. We had previously found that EBV, through activation of cellular STAT3 prevents phosphorylation of Chk1, and thereby, suppresses activation of the intra-S phase cell-cycle checkpoint, a potent barrier to oncogene-driven proliferation. This observation prompted us to examine the consequences on DNA repair since homologous recombination repair, the most error-free form, requires phosphoChk1. We now report that the defect in Chk1 phosphorylation also curtails RAD51 nucleation, and thereby, homologous recombination repair of DNA double strand breaks. The resulting reliance on error-prone microhomology-mediated end-joining (MMEJ) repair makes EBV-transformed cells susceptible to PARP inhibition and simultaneous accrual of genome-wide deletions and insertions resulting from synthesis-dependent MMEJ. Analysis of transcriptomic and drug susceptibility data from hundreds of cancer lines reveals a STAT3-dependent gene-set predictive of susceptibility of cancers to synthetic lethal PARP inhibition. These findings i) demonstrate how the tumor virus EBV re-shapes cellular DNA repair, ii) provide the first genome-wide evidence for insertions resulting from MMEJ in human cells, and iii) expand the range of cancers (EBV-related and -unrelated) that are likely to respond to synthetic lethal inhibitors given the high prevalence of cancers with constitutively active STAT3.
Collapse
Affiliation(s)
- Michael T. McIntosh
- Child Health Research Institute, Department of Pediatrics, University of Florida, Gainesville, FL, United States of America
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, United States of America
- * E-mail: (MTM); (SBM)
| | - Siva Koganti
- Division of Infectious Diseases, Department of Pediatrics, Stony Brook University, Stony Brook, NY, United States of America
| | - J. Lucas Boatwright
- Bioinformatics Core Facility, University of Florida, Gainesville, FL, United States of America
| | - Xiaofan Li
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, FL, United States of America
| | - Salvatore V. Spadaro
- Division of Infectious Diseases, Department of Pediatrics, Stony Brook University, Stony Brook, NY, United States of America
| | - Alexis C. Brantly
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, FL, United States of America
| | - Jasmine B. Ayers
- Division of Infectious Diseases, Department of Pediatrics, Stony Brook University, Stony Brook, NY, United States of America
| | - Ramon D. Perez
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, United States of America
| | - Eric M. Burton
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, FL, United States of America
| | - Sandeepta Burgula
- Division of Infectious Diseases, Department of Pediatrics, Stony Brook University, Stony Brook, NY, United States of America
| | - Thomas MacCarthy
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY, United States of America
| | - Sumita Bhaduri-McIntosh
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, United States of America
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, FL, United States of America
- * E-mail: (MTM); (SBM)
| |
Collapse
|
18
|
Xu Y, Lin Y, Luo Y, Yang Y, Long B, Fang Z, Liu L, Zhang J, Zhang X. RAD52 aptamer regulates DNA damage repair and STAT3 in BRCA1/BRCA2‑deficient human acute myeloid leukemia. Oncol Rep 2020; 44:1455-1466. [PMID: 32945515 PMCID: PMC7448423 DOI: 10.3892/or.2020.7723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 07/08/2020] [Indexed: 02/06/2023] Open
Abstract
RAD52 (Radiation sensitive 52) is a key factor in DNA damage repair (DDR) bypass, which participates in single-strand annealing (SSA) after DNA damage end excision, while breast cancer type 1 susceptibility protein (BRCA1)/breast cancer type 2 susceptibility protein (BRCA2) play critical roles in homologous recombination (HR) repair. The present study aimed to determine whether RAD52-induced regulation of repair bypass occurs in acute myeloid leukemia (AML) cells and to explore the underlying mechanism. Herein, we applied an RAD52 aptamer to AML cells with downregulated BRCA1/2. RAD52 aptamer inhibited AML cell proliferation detected by cell counting, promoted cell apoptosis obtained by flow cytometry, and suppressed DNA damage repair behavior measured by comet assay and flow cytometry, after drug intervention during low expression of BRCA1/2. During this process, DDR-related cell cycle checkpoint proteins were activated, and the cells were continuously arrested in the S/G2 phase, which affected the cell damage repair process. Concurrently, the expression levels of apoptosis-related proteins were also altered. Furthermore, the expression of STAT3 and p-STAT3 was downregulated by the RAD52 aptamer, suggesting that RAD52 affects the STAT3 signaling pathway. In summary, we present a possible role for RAD52 in DDR of BRCA1/2-deficient AML cells that involves the STAT3 signaling pathway.
Collapse
Affiliation(s)
- Yichuan Xu
- Department of Hematology, The Third Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510630, P.R. China
| | - Yansi Lin
- Department of General Medicine, Sun Yat‑sen Memorial Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510120, P.R. China
| | - Yuxuan Luo
- Department of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou, Guangdong 510623, P.R. China
| | - Yanling Yang
- Department of Hematology, The Third Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510630, P.R. China
| | - Bing Long
- Department of Hematology, The Third Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510630, P.R. China
| | - Zhigang Fang
- Department of Hematology, The Third Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510630, P.R. China
| | - Lingling Liu
- Department of Hematology, The Third Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510630, P.R. China
| | - Jingwen Zhang
- Department of Hematology, The Third Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510630, P.R. China
| | - Xiangzhong Zhang
- Department of Hematology, The Third Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510630, P.R. China
| |
Collapse
|
19
|
The Role of Ataxia Telangiectasia Mutant and Rad3-Related DNA Damage Response in Pathogenesis of Human Papillomavirus. Pathogens 2020; 9:pathogens9060506. [PMID: 32585979 PMCID: PMC7350315 DOI: 10.3390/pathogens9060506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 12/16/2022] Open
Abstract
Human papillomavirus (HPV) infection leads to a variety of benign lesions and malignant tumors such as cervical cancer and head and neck squamous cell carcinoma. Several HPV vaccines have been developed that can help to prevent cervical carcinoma, but these vaccines are only effective in individuals with no prior HPV infection. Thus, it is still important to understand the HPV life cycle and in particular the association of HPV with human pathogenesis. HPV production requires activation of the DNA damage response (DDR), which is a complex signaling network composed of multiple sensors, mediators, transducers, and effectors that safeguard cellular DNAs to maintain the host genome integrity. In this review, we focus on the roles of the ataxia telangiectasia mutant and Rad3-related (ATR) DNA damage response in HPV DNA replication. HPV can induce ATR expression and activate the ATR pathway. Inhibition of the ATR pathway results in suppression of HPV genome maintenance and amplification. The mechanisms underlying this could be through various molecular pathways such as checkpoint signaling and transcriptional regulation. In light of these findings, other downstream mechanisms of the ATR pathway need to be further investigated for better understanding HPV pathogenesis and developing novel ATR DDR-related inhibitors against HPV infection.
Collapse
|
20
|
Nascent Transcriptomics Reveal Cellular Prolytic Factors Upregulated Upstream of the Latent-to-Lytic Switch Protein of Epstein-Barr Virus. J Virol 2020; 94:JVI.01966-19. [PMID: 31941784 DOI: 10.1128/jvi.01966-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 01/08/2020] [Indexed: 12/15/2022] Open
Abstract
Lytic activation from latency is a key transition point in the life cycle of herpesviruses. Epstein-Barr virus (EBV) is a human herpesvirus that can cause lymphomas, epithelial cancers, and other diseases, most of which require the lytic cycle. While the lytic cycle of EBV can be triggered by chemicals and immunologic ligands, the lytic cascade is activated only when expression of the EBV latent-to-lytic switch protein ZEBRA is turned on. ZEBRA then transcriptionally activates other EBV genes and, together with some of those gene products, ensures completion of the lytic cycle. However, not every latently infected cell exposed to a lytic trigger turns on the expression of ZEBRA, resulting in responsive and refractory subpopulations. What governs this dichotomy? By examining the nascent transcriptome following exposure to a lytic trigger, we find that several cellular genes are transcriptionally upregulated temporally upstream of ZEBRA. These genes regulate lytic susceptibility to various degrees in latently infected cells that respond to mechanistically distinct lytic triggers. While increased expression of these cellular genes defines a prolytic state, such upregulation also runs counter to the well-known mechanism of viral-nuclease-mediated host shutoff that is activated downstream of ZEBRA. Furthermore, a subset of upregulated cellular genes is transcriptionally repressed temporally downstream of ZEBRA, indicating an additional mode of virus-mediated host shutoff through transcriptional repression. Thus, increased transcription of a set of host genes contributes to a prolytic state that allows a subpopulation of cells to support the EBV lytic cycle.IMPORTANCE Transition from latency to the lytic phase is necessary for herpesvirus-mediated pathology as well as viral spread and persistence in the population at large. Yet, viral genomes in only some cells in a population of latently infected cells respond to lytic triggers, resulting in subpopulations of responsive/lytic and refractory cells. Our investigations into this partially permissive phenotype of the herpesvirus Epstein-Barr virus (EBV) indicate that upon exposure to lytic triggers, certain cellular genes are transcriptionally upregulated, while viral latency genes are downregulated ahead of expression of the viral latent-to-lytic switch protein. These cellular genes contribute to lytic susceptibility to various degrees. Apart from indicating that there may be a cellular "prolytic" state, our findings indicate that (i) early transcriptional upregulation of cellular genes counters the well-known viral-nuclease-mediated host shutoff and (ii) subsequent transcriptional downregulation of a subset of early upregulated cellular genes is a previously undescribed mode of host shutoff.
Collapse
|
21
|
Novel replisome-associated proteins at cellular replication forks in EBV-transformed B lymphocytes. PLoS Pathog 2019; 15:e1008228. [PMID: 31841561 PMCID: PMC6936862 DOI: 10.1371/journal.ppat.1008228] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 12/30/2019] [Accepted: 11/20/2019] [Indexed: 01/08/2023] Open
Abstract
Epstein-Barr virus (EBV) is an oncogenic herpesvirus and WHO class 1 carcinogen that resides in B lymphocytes of nearly all humans. While silent in most, EBV can cause endemic Burkitt lymphoma in children and post-transplant lymphoproliferative disorders/lymphomas in immunocompromised hosts. The pathogenesis of such lymphomas is multifactorial but to a large extent depends on EBV’s ability to aggressively drive cellular DNA replication and B cell proliferation despite cell-intrinsic barriers to replication. One such barrier is oncogenic replication stress which hinders the progression of DNA replication forks. To understand how EBV successfully overcomes replication stress, we examined cellular replication forks in EBV-transformed B cells using iPOND (isolation of Proteins on Nascent DNA)-mass spectrometry and identified several cellular proteins that had not previously been linked to DNA replication. Of eight candidate replisome-associated proteins that we validated at forks in EBV-transformed cells and Burkitt lymphoma-derived cells, three zinc finger proteins (ZFPs) were upregulated early in B cells newly-infected with EBV in culture as well as expressed at high levels in EBV-infected B blasts in the blood of immunocompromised transplant recipients. Expressed highly in S- and G2-phase cells, knockdown of each ZFP resulted in stalling of proliferating cells in the S-phase, cleavage of caspase 3, and cell death. These proteins, newly-identified at replication forks of EBV-transformed and Burkitt lymphoma cells therefore contribute to cell survival and cell cycle progression, and represent novel targets for intervention of EBV-lymphomas while simultaneously offering a window into how the replication machinery may be similarly modified in other cancers. Cancer cells must overcome chronic replication stress, a central barrier to DNA replication. This is true also for cancers caused by Epstein-Barr virus (EBV). To understand how EBV overcomes this barrier to successfully drive cell proliferation, we isolated proteins associated with the cellular replication machinery in EBV-transformed B lymphocytes and identified several cellular proteins that had not previously been linked to DNA replication in cancer or healthy cells. Three of these were zinc finger proteins enriched at the replication machinery in EBV-transformed and EBV-positive Burkitt lymphoma-derived cells, upregulated in newly-infected B cells, and expressed at high levels in infected B cells from transplant recipients. These zinc finger proteins also contributed towards cell proliferation, survival, and cell cycle progression. While these proteins may also contribute to DNA replication in other cancers, they simultaneously represent potential targets in EBV-cancers, some of which are difficult to treat.
Collapse
|
22
|
Koganti S, Burgula S, Bhaduri-McIntosh S. STAT3 activates the anti-apoptotic form of caspase 9 in oncovirus-infected B lymphocytes. Virology 2019; 540:160-164. [PMID: 31928997 DOI: 10.1016/j.virol.2019.11.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 11/05/2019] [Accepted: 11/18/2019] [Indexed: 10/25/2022]
Abstract
The cancer-causing Epstein-Barr virus (EBV) activates the transcription factor STAT3 upon infecting B-lymphocytes. STAT3 then activates caspase 7 to degrade cellular claspin, resulting in impaired Chk1 phosphorylation. This blockade of ATR-Chk1 signaling allows EBV-transformed cells to proliferate despite DNA lesions from virus-induced replication stress. In addressing the mechanism of caspase 7 activation, we now report that in newly-infected B-cells, STAT3 transcriptionally activates the initiator caspase, caspase 9. Caspase 9 then activates caspase 7 to impair phosphorylation of Chk1 at S345. Importantly, although cleaved products of caspase 9 are detectable in infected cells, there is simultaneous increase in the alternatively-spliced dominant-negative form of caspase 9 - and - expression of dominant-negative caspase 9 is abrogated when STAT3 activation is impaired. Thus EBV, via STAT3, activates caspase 9 but also shifts the balance of transcripts towards its dominant-negative form to allow activation of caspase 7 while avoiding death of EBV-infected cells.
Collapse
Affiliation(s)
- Siva Koganti
- Division of Infectious Diseases, Department of Pediatrics, Stony Brook University, NY, USA
| | - Sandeepta Burgula
- Division of Infectious Diseases, Department of Pediatrics, Stony Brook University, NY, USA
| | - Sumita Bhaduri-McIntosh
- Division of Infectious Diseases, Department of Pediatrics, University of Florida, Gainesville, FL, USA; Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, USA.
| |
Collapse
|
23
|
Granato M, Gilardini Montani MS, Zompetta C, Santarelli R, Gonnella R, Romeo MA, D'Orazi G, Faggioni A, Cirone M. Quercetin Interrupts the Positive Feedback Loop Between STAT3 and IL-6, Promotes Autophagy, and Reduces ROS, Preventing EBV-Driven B Cell Immortalization. Biomolecules 2019; 9:biom9090482. [PMID: 31547402 PMCID: PMC6769872 DOI: 10.3390/biom9090482] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 09/06/2019] [Accepted: 09/07/2019] [Indexed: 12/17/2022] Open
Abstract
The oncogenic gammaherpesvirus Epstein–Barr virus (EBV) immortalizes in vitro B lymphocytes into lymphoblastoid cell lines (LCLs), a model that gives the opportunity to explore the molecular mechanisms driving viral tumorigenesis. In this study, we addressed the potential of quercetin, a widely distributed flavonoid displaying antioxidant, anti-inflammatory, and anti-cancer properties, in preventing EBV-driven B cell immortalization. The results obtained indicated that quercetin inhibited thectivation of signal transducer and activator of transcription 3 (STAT3) induced by EBV infection and reduced molecules such as interleukin-6 (IL-6) and reactive oxidative species (ROS) known to be essential for the immortalization process. Moreover, we found that quercetin promoted autophagy and counteracted the accumulation of sequestosome1/p62 (SQSTM1/p62), ultimately leading to the prevention of B cell immortalization. These findings suggest that quercetin may have the potential to be used to counteract EBV-driven lymphomagenesis, especially if its stability is improved.
Collapse
Affiliation(s)
- Marisa Granato
- Department of Experimental Medicine, "Sapienza" University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, 00161 Rome, Italy.
| | - Maria Saveria Gilardini Montani
- Department of Experimental Medicine, "Sapienza" University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, 00161 Rome, Italy.
| | - Claudia Zompetta
- Department of Experimental Medicine, "Sapienza" University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, 00161 Rome, Italy.
| | - Roberta Santarelli
- Department of Experimental Medicine, "Sapienza" University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, 00161 Rome, Italy.
| | - Roberta Gonnella
- Department of Experimental Medicine, "Sapienza" University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, 00161 Rome, Italy.
| | - Maria Anele Romeo
- Department of Experimental Medicine, "Sapienza" University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, 00161 Rome, Italy.
| | - Gabriella D'Orazi
- Translational Research Area, Regina Elena National Cancer Institute, 00128 Rome, Italy.
- Department of Medical, Oral and Biotechnological Sciences, University "G. d'Annunzio", 66013 Chieti, Italy.
| | - Alberto Faggioni
- Department of Experimental Medicine, "Sapienza" University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, 00161 Rome, Italy.
| | - Mara Cirone
- Department of Experimental Medicine, "Sapienza" University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, 00161 Rome, Italy.
| |
Collapse
|
24
|
Abstract
Alterations in DNA damage response (DDR) pathways are hallmarks of cancer. Incorrect repair of DNA lesions often leads to genomic instability. Ataxia telangiectasia mutated (ATM), a core component of the DNA repair system, is activated to enhance the homologous recombination (HR) repair pathway upon DNA double-strand breaks. Although ATM signaling has been widely studied in different types of cancer, its research is still lacking compared with other DDR-involved molecules such as PARP and ATR. There is still a vast research opportunity for the development of ATM inhibitors as anticancer agents. Here, we focus on the recent findings of ATM signaling in DNA repair of cancer. Previous studies have identified several partners of ATM, some of which promote ATM signaling, while others have the opposite effect. ATM inhibitors, including KU-55933, KU-60019, KU-59403, CP-466722, AZ31, AZ32, AZD0156, and AZD1390, have been evaluated for their antitumor effects. It has been revealed that ATM inhibition increases a cancer cell's sensitivity to radiotherapy. Moreover, the combination with PARP or ATR inhibitors has synergistic lethality in some cancers. Of note, among these ATM inhibitors, AZD0156 and AZD1390 achieve potent and highly selective ATM kinase inhibition and have an excellent ability to penetrate the blood-brain barrier. Currently, AZD0156 and AZD1390 are under investigation in phase I clinical trials. Taken together, targeting ATM may be a promising strategy for cancer treatment. Hence, further development of ATM inhibitors is urgently needed in cancer research.
Collapse
Affiliation(s)
- Mei Hua Jin
- Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Do-Youn Oh
- Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Internal Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
| |
Collapse
|
25
|
Wang C, Li D, Zhang L, Jiang S, Liang J, Narita Y, Hou I, Zhong Q, Zheng Z, Xiao H, Gewurz BE, Teng M, Zhao B. RNA Sequencing Analyses of Gene Expression during Epstein-Barr Virus Infection of Primary B Lymphocytes. J Virol 2019; 93:e00226-19. [PMID: 31019051 PMCID: PMC6580941 DOI: 10.1128/jvi.00226-19] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 04/05/2019] [Indexed: 12/23/2022] Open
Abstract
Epstein-Barr virus (EBV) infection of human primary resting B lymphocytes (RBLs) leads to the establishment of lymphoblastoid cell lines (LCLs) that can grow indefinitely in vitro EBV transforms RBLs through the expression of viral latency genes, and these genes alter host transcription programs. To globally measure the transcriptome changes during EBV transformation, primary human resting B lymphocytes (RBLs) were infected with B95.8 EBV for 0, 2, 4, 7, 14, 21, and 28 days, and poly(A) plus RNAs were analyzed by transcriptome sequencing (RNA-seq). Analyses of variance (ANOVAs) found 3,669 protein-coding genes that were differentially expressed (false-discovery rate [FDR] < 0.01). Ninety-four percent of LCL genes that are essential for LCL growth and survival were differentially expressed. Pathway analyses identified a significant enrichment of pathways involved in cell proliferation, DNA repair, metabolism, and antiviral responses. RNA-seq also identified long noncoding RNAs (lncRNAs) differentially expressed during EBV infection. Clustered regularly interspaced short palindromic repeat (CRISPR) interference (CRISPRi) and CRISPR activation (CRISPRa) found that CYTOR and NORAD lncRNAs were important for LCL growth. During EBV infection, type III EBV latency genes were expressed rapidly after infection. Immediately after LCL establishment, EBV lytic genes were also expressed in LCLs, and ∼4% of the LCLs express gp350. Chromatin immune precipitation followed by deep sequencing (ChIP-seq) and POLR2A chromatin interaction analysis followed by paired-end tag sequencing (ChIA-PET) data linked EBV enhancers to 90% of EBV-regulated genes. Many genes were linked to enhancers occupied by multiple EBNAs or NF-κB subunits. Incorporating these assays, we generated a comprehensive EBV regulome in LCLs.IMPORTANCE Epstein-Barr virus (EBV) immortalization of resting B lymphocytes (RBLs) is a useful model system to study EBV oncogenesis. By incorporating transcriptome sequencing (RNA-seq), chromatin immune precipitation followed by deep sequencing (ChIP-seq), chromatin interaction analysis followed by paired-end tag sequencing (ChIA-PET), and genome-wide clustered regularly interspaced short palindromic repeat (CRISPR) screen, we identified key pathways that EBV usurps to enable B cell growth and transformation. Multiple layers of regulation could be achieved by cooperations between multiple EBV transcription factors binding to the same enhancers. EBV manipulated the expression of most cell genes essential for lymphoblastoid cell line (LCL) growth and survival. In addition to proteins, long noncoding RNAs (lncRNAs) regulated by EBV also contributed to LCL growth and survival. The data presented in this paper not only allowed us to further define the molecular pathogenesis of EBV but also serve as a useful resource to the EBV research community.
Collapse
Affiliation(s)
- Chong Wang
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Difei Li
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Luyao Zhang
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
- Department of Medicine, the First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Sizun Jiang
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Jun Liang
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Yohei Narita
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Isabella Hou
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Qian Zhong
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Zeguang Zheng
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Haipeng Xiao
- Department of Medicine, the First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Benjamin E Gewurz
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Mingxiang Teng
- Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, USA
| | - Bo Zhao
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
26
|
Marek's Disease Virus Disables the ATR-Chk1 Pathway by Activating STAT3. J Virol 2019; 93:JVI.02290-18. [PMID: 30787154 DOI: 10.1128/jvi.02290-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Accepted: 02/12/2019] [Indexed: 01/05/2023] Open
Abstract
Oncogenic virus replication often leads to genomic instability, causing DNA damage and inducing the DNA damage response (DDR) pathway. The DDR pathway is a cellular pathway that senses DNA damage and regulates the cell cycle to maintain genomic stability. Therefore, the DDR pathway is critical for the viral lifecycle and tumorigenesis. Marek's disease virus (MDV), an alphaherpesvirus that causes lymphoma in chickens, has been shown to induce DNA damage in infected cells. However, the interaction between MDV and the host DDR is unclear. In this study, we observed that MDV infection causes DNA strand breakage in chicken fibroblast (CEF) cells along with an increase in the DNA damage markers p53 and p21. Interestingly, we showed that phosphorylation of STAT3 was increased during MDV infection, concomitantly with a decrease of Chk1 phosphorylation. In addition, we found that MDV infection was enhanced by VE-821, an ATR-specific inhibitor, but attenuated by hydroxyurea, an ATR activator. Moreover, inhibition of STAT3 phosphorylation by Stattic eliminates the ability of MDV to inhibit Chk1 phosphorylation. Finally, we showed that MDV replication was decreased by Stattic treatment. Taken together, these results suggest that MDV disables the ATR-Chk1 pathway through STAT3 activation to benefit its replication.IMPORTANCE MDV is used as a biomedical model to study virus-induced lymphoma due to the similar genomic structures and physiological characteristics of MDV and human herpesviruses. Upon infection, MDV induces DNA damage, which may activate the DDR pathway. The DDR pathway has a dual impact on viruses because it manipulates repair and recombination factors to facilitate viral replication and also initiates antiviral action by regulating other signaling pathways. Many DNA viruses evolve to manipulate the DDR pathway to promote virus replication. In this study, we identified a mechanism used by MDV to inhibit ATR-Chk1 pathways. ATR is a cellular kinase that responds to broken single-stranded DNA, which has been less studied in MDV infection. Our results suggest that MDV infection activates STAT3 to disable the ATR-Chk1 pathway, which is conducive to viral replication. This finding provides new insight into the role of STAT3 in interrupting the ATR-Chk1 pathway during MDV replication.
Collapse
|
27
|
Zhang B, Cui B, Du J, Shen X, Wang K, Chen J, Xiao L, Sun C, Li Y. ATR activated by EB virus facilitates chemotherapy resistance to cisplatin or 5-fluorouracil in human nasopharyngeal carcinoma. Cancer Manag Res 2019; 11:573-585. [PMID: 30666155 PMCID: PMC6331066 DOI: 10.2147/cmar.s187099] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Purpose Epstein-Barr virus (EBV) infection is closely associated with nasopharyngeal carcinoma (NPC) and increases the chemotherapy resistance of tumor cells. Although the mechanism by which EBV manipulates ataxia telangiectasia mutation (ATM)-mediated DNA damage response in NPC has been extensively studied, the relationship between ATR (ATM and Rad-3 related) and EBV infection is largely unexplored, and also the role of ATR in chemotherapy resistance in EBV-positive NPC has not been specifically reported. Materials and methods Levels of γ-H2AX, latent membrane protein 1 (LMP1), and EBV-encoded RNA in clinical NPC and nasopharyngeal inflammation (NPI) specimens were examined using immunohistochemistry and in situ hybridization. The effects of EBV infection, chemotherapy drugs cisplatin (CDDP) and 5-fluorouracil (5-FU) treatment, and ATR silencing were assessed in NPC cells in vitro using immunofluorescence, Western blot, and flow cytometry. Results A notable increase of γ-H2AX expression was examined in the EBV-positive NPC clinical specimens. Additionally, we observed that the phosphorylation of ATR/checkpoint kinase 1 (CHK1) pathway protein was gradually activated along with the duration of EBV exposure in NPC cell lines, which was obviously inhibited after ATR depletion. Moreover, EBV infection promoted the resistance of NPC cells to CDDP and 5-FU, whereas the chemosensitivity of cells was significantly enhanced following ATR knockdown. Furthermore, ATR depletion caused both S-phase cell arrest and apoptosis, enhanced p53 phosphorylation, and impaired the formation of Rad51. Conclusion Our data suggest that EBV activation of ATR-mediated DNA damage response might result in chemotherapy resistance to CDDP and 5-FU in NPC. Accordingly, ATR knockdown may serve as an effective treatment strategy for chemotherapy-resistant, EBV-positive NPC.
Collapse
Affiliation(s)
- Bo Zhang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China, ;
| | - Bomiao Cui
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China, ;
| | - Jintao Du
- Department of Otorhinolaryngology-Head and Neck Surgery, West China Hospital, Chengdu 610041, Sichuan, China
| | - Xin Shen
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China, ;
| | - Kun Wang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China, ;
| | - Jiao Chen
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China, ;
| | - Liying Xiao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China, ;
| | - Chongkui Sun
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China, ;
| | - Yan Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China, ;
| |
Collapse
|
28
|
Azenha D, Lopes MC, Martins TC. Claspin: From replication stress and DNA damage responses to cancer therapy. DNA Repair (Amst) 2019; 115:203-246. [DOI: 10.1016/bs.apcsb.2018.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
29
|
Zhang J, Dang F, Ren J, Wei W. Biochemical Aspects of PD-L1 Regulation in Cancer Immunotherapy. Trends Biochem Sci 2018; 43:1014-1032. [PMID: 30287140 DOI: 10.1016/j.tibs.2018.09.004] [Citation(s) in RCA: 142] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 09/04/2018] [Accepted: 09/11/2018] [Indexed: 12/13/2022]
Abstract
PD-L1, frequently expressed in human cancers, engages with PD-1 on immune cells and contributes to cancer immune evasion. As such, antibodies blocking the PD-1/PD-L1 interaction reactivate cytotoxic T cells to eradicate cancer cells. However, a majority of cancer patients fail to respond to PD-1/PD-L1 blockade with unclear underlying mechanism(s). Recent studies revealed that PD-L1 expression levels on tumor cells might affect the clinical response to anti-PD-1/PD-L1 therapies. Hence, understanding molecular mechanisms for controlling PD-L1 expression will be important to improve the clinical response rate and efficacy of PD-1/PD-L1 blockade. In this review, we primarily focus on summarizing PD-L1 regulation and its potential roles in regulating antitumor immune response, with purpose to optimize anti-PD-1/PD-L1 therapies, benefiting a wider cancer patient population.
Collapse
Affiliation(s)
- Jinfang Zhang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; These authors contributed equally to this work
| | - Fabin Dang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; These authors contributed equally to this work
| | - Junming Ren
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| |
Collapse
|
30
|
Vallabhaneni H, Lynch PJ, Chen G, Park K, Liu Y, Goehe R, Mallon BS, Boehm M, Hursh DA. High Basal Levels of γH2AX in Human Induced Pluripotent Stem Cells Are Linked to Replication-Associated DNA Damage and Repair. Stem Cells 2018; 36:1501-1513. [PMID: 29873142 DOI: 10.1002/stem.2861] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 05/02/2018] [Accepted: 05/19/2018] [Indexed: 01/07/2023]
Abstract
Human induced pluripotent stem cells (iPSCs) have great potential as source cells for therapeutic uses. However, reports indicate that iPSCs carry genetic abnormalities, which may impede their medical use. Little is known about mechanisms contributing to intrinsic DNA damage in iPSCs that could lead to genomic instability. In this report, we investigated the level of DNA damage in human iPSC lines compared with their founder fibroblast line and derived mesenchymal stromal cell (MSC) lines using the phosphorylated histone variant, γH2AX, as a marker of DNA damage. We show that human iPSCs have elevated basal levels of γH2AX, which correlate with markers of DNA replication: 5-ethynyl-2'-deoxyuridine and the single-stranded binding protein, replication protein A. γH2AX foci in iPSCs also colocalize to BRCA1 and RAD51, proteins in the homologous repair pathway, implying γH2AX in iPSCs marks sites of double strand breaks. Our study demonstrates an association between increased basal levels of γH2AX and the rapid replication of iPSCs. Stem Cells 2018;36:1501-1513.
Collapse
Affiliation(s)
- Haritha Vallabhaneni
- Division of Cellular and Gene Therapy, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Patrick J Lynch
- Division of Biotechnology Review and Research II, Office of Pharmaceutical Quality, Center for Drugs Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Guibin Chen
- Laboratory of Cardiovascular Regenerative Medicine, National Heart, Lung and Blood Institute, Bethesda, Maryland, USA
| | - Kyeyoon Park
- Stem Cell Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Yangtengyu Liu
- Laboratory of Cardiovascular Regenerative Medicine, National Heart, Lung and Blood Institute, Bethesda, Maryland, USA
| | - Rachel Goehe
- Division of Cellular and Gene Therapy, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Barbara S Mallon
- Stem Cell Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Manfred Boehm
- Laboratory of Cardiovascular Regenerative Medicine, National Heart, Lung and Blood Institute, Bethesda, Maryland, USA
| | - Deborah A Hursh
- Division of Cellular and Gene Therapy, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| |
Collapse
|
31
|
Smits VAJ, Cabrera E, Freire R, Gillespie DA. Claspin – checkpoint adaptor and
DNA
replication factor. FEBS J 2018; 286:441-455. [DOI: 10.1111/febs.14594] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 06/13/2018] [Accepted: 06/20/2018] [Indexed: 12/16/2022]
Affiliation(s)
- Veronique A. J. Smits
- Hospital Universitario de Canarias Unidad de Investigación La Laguna Tenerife Spain
- Facultad de Medicina Instituto de Tecnologías Biomédicas Centro de Investigaciones Biomédicas de Canarias Universidad de La Laguna Tenerife Spain
| | - Elisa Cabrera
- Hospital Universitario de Canarias Unidad de Investigación La Laguna Tenerife Spain
- Facultad de Medicina Instituto de Tecnologías Biomédicas Centro de Investigaciones Biomédicas de Canarias Universidad de La Laguna Tenerife Spain
| | - Raimundo Freire
- Hospital Universitario de Canarias Unidad de Investigación La Laguna Tenerife Spain
- Facultad de Medicina Instituto de Tecnologías Biomédicas Centro de Investigaciones Biomédicas de Canarias Universidad de La Laguna Tenerife Spain
| | - David A. Gillespie
- Facultad de Medicina Instituto de Tecnologías Biomédicas Centro de Investigaciones Biomédicas de Canarias Universidad de La Laguna Tenerife Spain
| |
Collapse
|
32
|
STAT3 Interactors as Potential Therapeutic Targets for Cancer Treatment. Int J Mol Sci 2018; 19:ijms19061787. [PMID: 29914167 PMCID: PMC6032216 DOI: 10.3390/ijms19061787] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/13/2018] [Accepted: 06/14/2018] [Indexed: 02/07/2023] Open
Abstract
Signal transducers and activators of transcription (STATs) mediate essential signaling pathways in different biological processes, including immune responses, hematopoiesis, and neurogenesis. Among the STAT members, STAT3 plays crucial roles in cell proliferation, survival, and differentiation. While STAT3 activation is transient in physiological conditions, STAT3 becomes persistently activated in a high percentage of solid and hematopoietic malignancies (e.g., melanoma, multiple myeloma, breast, prostate, ovarian, and colon cancers), thus contributing to malignant transformation and progression. This makes STAT3 an attractive therapeutic target for cancers. Initial strategies aimed at inhibiting STAT3 functions have focused on blocking the action of its activating kinases or sequestering its DNA binding ability. More recently, the diffusion of proteomic-based techniques, which have allowed for the identification and characterization of novel STAT3-interacting proteins able to modulate STAT3 activity via its subcellular localization, interact with upstream kinases, and recruit transcriptional machinery, has raised the possibility to target such cofactors to specifically restrain STAT3 oncogenic functions. In this article, we summarize the available data about the function of STAT3 interactors in malignant cells and discuss their role as potential therapeutic targets for cancer treatment.
Collapse
|
33
|
Shi Q, Shen LY, Dong B, Fu H, Kang XZ, Yang YB, Dai L, Yan WP, Xiong HC, Liang Z, Chen KN. The identification of the ATR inhibitor VE-822 as a therapeutic strategy for enhancing cisplatin chemosensitivity in esophageal squamous cell carcinoma. Cancer Lett 2018; 432:56-68. [PMID: 29890208 DOI: 10.1016/j.canlet.2018.06.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Revised: 05/12/2018] [Accepted: 06/06/2018] [Indexed: 12/11/2022]
Abstract
Inducing DNA damage is known to be one of the mechanisms of cytotoxic chemotherapy agents for cancer such as cisplatin. The endogenous DNA damage response confers chemoresistance to these agents by repairing DNA damage. The initiation and transduction of the DNA damage response (DDR) signaling pathway, which is dependent on the activation of ATM (ataxia-telangiectasia mutated) and ATR (ataxia telangiectasia and Rad3-related), is essential for DNA damage repair, the maintenance of genomic stability and cell survival. Therefore, ATM or ATR inhibition is considered as a promising strategy for sensitizing cancer cells to chemotherapy. This study is aimed to explore the effect of ATR inhibitor on sensitizing ESCC (esophageal squamous cell carcinoma) cells to cisplatin, and whether ATM deficiency could impact the sensitization. We found that 21.5% of ESCC cases had ATM deficiency and that patients with ATR activation after neoadjuvant chemotherapy had worse chemotherapy response and poorer overall survival than that without ATR activation (32 mons vs. >140mons). Then, it was shown that VE-822 inhibited ATR-CHK1 pathway activation, leading to the accumulation of cisplatin-modified DNA. And it inhibited cell proliferation, induced cell cycle arrest in G1 phase and enhanced cell apoptosis. Moreover, VE-822 significantly sensitized ESCC cells to cisplatin, and these two drugs had synergistic effects, especially in ATM-deficient cells, in vitro and in vivo. Our results suggest that ATR inhibition combining with cisplatin is a new strategy for managing patients with ESCC, especially those with ATM-deficiency. However, this is an idea that requires further validation.
Collapse
Affiliation(s)
- Qi Shi
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Lu-Yan Shen
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Bin Dong
- Department of Pathology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Hao Fu
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Xiao-Zheng Kang
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Yong-Bo Yang
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Liang Dai
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Wan-Pu Yan
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Hong-Chao Xiong
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Zhen Liang
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China
| | - Ke-Neng Chen
- Department of Thoracic Surgery I, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, People's Republic of China.
| |
Collapse
|
34
|
Chen H, Pan J, Zhang L, Chen L, Qi H, Zhong M, Shi X, Du J, Li Q. Downregulation of estrogen-related receptor alpha inhibits human cutaneous squamous cell carcinoma cell proliferation and migration by regulating EMT via fibronectin and STAT3 signaling pathways. Eur J Pharmacol 2018; 825:133-142. [PMID: 29476880 DOI: 10.1016/j.ejphar.2018.02.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 02/09/2018] [Accepted: 02/16/2018] [Indexed: 12/15/2022]
Abstract
Estrogen-related receptor alpha (ERRα), one of orphan nuclear receptors, has been recently revealed as an oncogenic regulator in a variety of cancers. However, the linking gain of ERRα expression and cancer progression in cutaneous squamous cell carcinoma (cSCC) is largely unknown. Here, we showed that the mRNA and protein expression levels of ERRα were markedly higher in A431 cells compared with human keratinocyte cell line HaCaT, and targeted inhibition of ERRα by shRNA or its inverse agonist XCT790 significantly suppressed A431 cells proliferation and migration, while overexpression of ERRα promoted cell proliferation and migration. In addition, the data revealed that ERRα downregulation markedly inhibited the epithelial mesenchymal transition (EMT) of A431 cells with increasing the expression of E-cadherin and decreasing fibronectin (FN) and vimentin. Results from further experiments using Western blot suggested that ERRα suppression inhibited signal transducer and activator of transcription (STAT3) protein expression. In contrast, overexpression of ERRα promoted EMT and the activation of STAT3 pathway. Moreover, treatment with specific STAT3 inhibitor reversed EMT markers in ERRα-overexpressing A431 cells. In tumor xenografts of A431 cells, we further showed that ERRα depletion inhibited cSCC tumor growth in vivo. Taken together, these results demonstrate, for the first time, that ERRα may function as an oncoprotein in cSCC to accelerate tumor aggressiveness by promoting EMT via FN and STAT3 pathway, and it could be a novel target for cSCC therapy.
Collapse
Affiliation(s)
- Haifei Chen
- Department of Pharmacy, Huashan Hospital North, Fudan University, Shanghai 201907, China
| | - Jiewen Pan
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Liudi Zhang
- Department of Pharmacy, Huashan Hospital North, Fudan University, Shanghai 201907, China
| | - Lu Chen
- Department of Pharmacy, Huashan Hospital North, Fudan University, Shanghai 201907, China
| | - Huijie Qi
- Department of Pharmacy, Huashan Hospital North, Fudan University, Shanghai 201907, China
| | - Mingkang Zhong
- Department of Pharmacy, Huashan Hospital North, Fudan University, Shanghai 201907, China; Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Xiaojin Shi
- Department of Pharmacy, Huashan Hospital North, Fudan University, Shanghai 201907, China; Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Juan Du
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai 200040, China.
| | - Qunyi Li
- Department of Pharmacy, Huashan Hospital North, Fudan University, Shanghai 201907, China; Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai 200040, China.
| |
Collapse
|
35
|
Morgan EL, Wasson CW, Hanson L, Kealy D, Pentland I, McGuire V, Scarpini C, Coleman N, Arthur JSC, Parish JL, Roberts S, Macdonald A. STAT3 activation by E6 is essential for the differentiation-dependent HPV18 life cycle. PLoS Pathog 2018; 14:e1006975. [PMID: 29630659 PMCID: PMC5908086 DOI: 10.1371/journal.ppat.1006975] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 04/19/2018] [Accepted: 03/15/2018] [Indexed: 02/06/2023] Open
Abstract
Human papillomaviruses (HPV) activate a number of host factors to control their differentiation-dependent life cycles. The transcription factor signal transducer and activator of transcription (STAT)-3 is important for cell cycle progression and cell survival in response to cytokines and growth factors. STAT3 requires phosphorylation on Ser727, in addition to phosphorylation on Tyr705 to be transcriptionally active. In this study, we show that STAT3 is essential for the HPV life cycle in undifferentiated and differentiated keratinocytes. Primary human keratinocytes containing high-risk HPV18 genomes display enhanced STAT3 phosphorylation compared to normal keratinocytes. Expression of the E6 oncoprotein is sufficient to induce the dual phosphorylation of STAT3 at Ser727 and Tyr705 by a mechanism requiring Janus kinases and members of the MAPK family. E6-mediated activation of STAT3 induces the transcription of STAT3 responsive genes including cyclin D1 and Bcl-xL. Silencing of STAT3 protein expression by siRNA or inhibition of STAT3 activation by small molecule inhibitors, or by expression of dominant negative STAT3 phosphorylation site mutants, results in blockade of cell cycle progression. Loss of active STAT3 impairs HPV gene expression and prevents episome maintenance in undifferentiated keratinocytes and upon differentiation, lack of active STAT3 abolishes virus genome amplification and late gene expression. Organotypic raft cultures of HPV18 containing keratinocytes expressing a phosphorylation site STAT3 mutant display a profound reduction in suprabasal hyperplasia, which correlates with a loss of cyclin B1 expression and increased differentiation. Finally, increased STAT3 expression and phosphorylation is observed in HPV positive cervical disease biopsies compared to control samples, highlighting a role for STAT3 activation in cervical carcinogenesis. In summary, our data provides evidence of a critical role for STAT3 in the HPV18 life cycle.
Collapse
Affiliation(s)
- Ethan L. Morgan
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Christopher W. Wasson
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Lucy Hanson
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - David Kealy
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Ieisha Pentland
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Victoria McGuire
- Division of Cell Signalling and Immunology, College of Life Sciences, Sir James Black Centre, University of Dundee, Dundee, United Kingdom
| | - Cinzia Scarpini
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Nicholas Coleman
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - J. Simon C. Arthur
- Division of Cell Signalling and Immunology, College of Life Sciences, Sir James Black Centre, University of Dundee, Dundee, United Kingdom
| | - Joanna L. Parish
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Sally Roberts
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Andrew Macdonald
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
- * E-mail:
| |
Collapse
|
36
|
Pancholi NJ, Price AM, Weitzman MD. Take your PIKK: tumour viruses and DNA damage response pathways. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0269. [PMID: 28893936 DOI: 10.1098/rstb.2016.0269] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/12/2017] [Indexed: 12/13/2022] Open
Abstract
Viruses regulate cellular processes to facilitate viral replication. Manipulation of nuclear proteins and pathways by nuclear replicating viruses often causes cellular genome instability that contributes to transformation. The cellular DNA damage response (DDR) safeguards the host to maintain genome integrity, but DNA tumour viruses can manipulate the DDR to promote viral propagation. In this review, we describe the interactions of DNA tumour viruses with the phosphatidylinositol 3-kinase-like protein kinase (PIKK) pathways, which are central regulatory arms of the DDR. We review how signalling through the ataxia telangiectasia mutated (ATM), ataxia telangiectasia and Rad3 related (ATR), and DNA-dependent protein kinases (DNA-PK) influences viral life cycles, and how their manipulation by viral proteins may contribute to tumour formation.This article is part of the themed issue 'Human oncogenic viruses'.
Collapse
Affiliation(s)
- Neha J Pancholi
- Division of Cancer Pathobiology and Division of Protective Immunity, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.,Cell and Molecular Biology Graduate Program, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Alexander M Price
- Division of Cancer Pathobiology and Division of Protective Immunity, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Matthew D Weitzman
- Division of Cancer Pathobiology and Division of Protective Immunity, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA .,Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| |
Collapse
|
37
|
Shair KHY, Reddy A, Cooper VS. New Insights from Elucidating the Role of LMP1 in Nasopharyngeal Carcinoma. Cancers (Basel) 2018; 10:cancers10040086. [PMID: 29561768 PMCID: PMC5923341 DOI: 10.3390/cancers10040086] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 03/16/2018] [Accepted: 03/20/2018] [Indexed: 12/11/2022] Open
Abstract
Latent membrane protein 1 (LMP1) is an Epstein-Barr virus (EBV) oncogenic protein that has no intrinsic enzymatic activity or sequence homology to cellular or viral proteins. The oncogenic potential of LMP1 has been ascribed to pleiotropic signaling properties initiated through protein-protein interactions in cytosolic membrane compartments, but the effects of LMP1 extend to nuclear and extracellular processes. Although LMP1 is one of the latent genes required for EBV-immortalization of B cells, the biology of LMP1 in the pathogenesis of the epithelial cancer nasopharyngeal carcinoma (NPC) is more complex. NPC is prevalent in specific regions of the world with high incidence in southeast China. The epidemiology and time interval from seroconversion to NPC onset in adults would suggest the involvement of multiple risk factors that complement the establishment of a latent and persistent EBV infection. The contribution of LMP1 to EBV pathogenesis in polarized epithelia has only recently begun to be elucidated. Furthermore, the LMP1 gene has emerged as one of the most divergent sequences in the EBV genome. This review will discuss the significance of recent advances in NPC research from elucidating LMP1 function in epithelial cells and lessons that could be learned from mining LMP1 sequence diversity.
Collapse
Affiliation(s)
- Kathy H Y Shair
- Cancer Virology Program, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA.
- Department of Microbiology and Molecular Genetics, and Center for Evolutionary Biology and Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA.
| | - Akhil Reddy
- Cancer Virology Program, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA.
| | - Vaughn S Cooper
- Department of Microbiology and Molecular Genetics, and Center for Evolutionary Biology and Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA.
| |
Collapse
|
38
|
Hafez AY, Luftig MA. Characterization of the EBV-Induced Persistent DNA Damage Response. Viruses 2017; 9:E366. [PMID: 29194355 PMCID: PMC5744141 DOI: 10.3390/v9120366] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 11/21/2017] [Accepted: 11/23/2017] [Indexed: 12/21/2022] Open
Abstract
Epstein-Barr virus (EBV) is an oncogenic herpesvirus that is ubiquitous in the human population. Early after EBV infection in vitro, primary human B cells undergo a transient period of hyper-proliferation, which results in replicative stress and DNA damage, activation of the DNA damage response (DDR) pathway and, ultimately, senescence. In this study, we investigated DDR-mediated senescence in early arrested EBV-infected B cells and characterized the establishment of persistent DNA damage foci. We found that arrested EBV-infected B cells exhibited an increase in promyelocytic leukemia nuclear bodies (PML NBs), which predominantly localized to markers of DNA damage, as well as telomeric DNA. Furthermore, arrested EBV-infected B cells exhibited an increase in the presence of telomere dysfunction-induced foci. Importantly, we found that increasing human telomerase reverse transcriptase (hTERT) expression with danazol, a drug used to treat telomere diseases, permitted early EBV-infected B cells to overcome cellular senescence and enhanced transformation. Finally, we report that EBV-infected B cells undergoing hyper-proliferation are more sensitive than lymphoblastoid cell lines (LCLs) to inhibition of Bloom syndrome-associated helicase, which facilitates telomere replication. Together, our results describe the composition of persistent DNA damage foci in the early stages of EBV infection and define key regulators of this barrier to long-term outgrowth.
Collapse
Affiliation(s)
- Amy Y Hafez
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC 27710, USA.
| | - Micah A Luftig
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC 27710, USA.
| |
Collapse
|
39
|
Hau PM, Tsao SW. Epstein-Barr Virus Hijacks DNA Damage Response Transducers to Orchestrate Its Life Cycle. Viruses 2017; 9:v9110341. [PMID: 29144413 PMCID: PMC5707548 DOI: 10.3390/v9110341] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/30/2017] [Accepted: 11/08/2017] [Indexed: 12/12/2022] Open
Abstract
The Epstein–Barr virus (EBV) is a ubiquitous virus that infects most of the human population. EBV infection is associated with multiple human cancers, including Burkitt’s lymphoma, Hodgkin’s lymphoma, a subset of gastric carcinomas, and almost all undifferentiated non-keratinizing nasopharyngeal carcinoma. Intensive research has shown that EBV triggers a DNA damage response (DDR) during primary infection and lytic reactivation. The EBV-encoded viral proteins have been implicated in deregulating the DDR signaling pathways. The consequences of DDR inactivation lead to genomic instability and promote cellular transformation. This review summarizes the current understanding of the relationship between EBV infection and the DDR transducers, including ATM (ataxia telangiectasia mutated), ATR (ATM and Rad3-related), and DNA-PK (DNA-dependent protein kinase), and discusses how EBV manipulates the DDR signaling pathways to complete the replication process of viral DNA during lytic reactivation.
Collapse
Affiliation(s)
- Pok Man Hau
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
| | - Sai Wah Tsao
- School of Biomedical Science, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
| |
Collapse
|
40
|
Hong SY. DNA damage response is hijacked by human papillomaviruses to complete their life cycle. J Zhejiang Univ Sci B 2017; 18:215-232. [PMID: 28271657 DOI: 10.1631/jzus.b1600306] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The DNA damage response (DDR) is activated when DNA is altered by intrinsic or extrinsic agents. This pathway is a complex signaling network and plays important roles in genome stability, tumor transformation, and cell cycle regulation. Human papillomaviruses (HPVs) are the main etiological agents of cervical cancer. Cervical cancer ranks as the fourth most common cancer among women and the second most frequent cause of cancer-related death worldwide. Over 200 types of HPVs have been identified and about one third of these infect the genital tract. The HPV life cycle is associated with epithelial differentiation. Recent studies have shown that HPVs deregulate the DDR to achieve a productive life cycle. In this review, I summarize current findings about how HPVs mediate the ataxia-telangiectasia mutated kinase (ATM) and the ATM-and RAD3-related kinase (ATR) DDRs, and focus on the roles that ATM and ATR signalings play in HPV viral replication. In addition, I demonstrate that the signal transducer and activator of transcription-5 (STAT)-5, an important immune regulator, can promote ATM and ATR activations through different mechanisms. These findings may provide novel opportunities for development of new therapeutic targets for HPV-related cancers.
Collapse
Affiliation(s)
- Shi-Yuan Hong
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| |
Collapse
|
41
|
Azenha D, Lopes MC, Martins TC. Claspin functions in cell homeostasis-A link to cancer? DNA Repair (Amst) 2017; 59:27-33. [PMID: 28942358 DOI: 10.1016/j.dnarep.2017.09.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 09/06/2017] [Indexed: 10/18/2022]
Abstract
Cancer remains one of the leading causes of mortality worldwide. Most cancers present high degrees of genomic instability. DNA damage and replication checkpoints function as barriers to halt cell cycle progression until damage is resolved, preventing the perpetuation of errors. Activation of these checkpoints is critically dependent on Claspin, an adaptor protein that mediates the phosphorylation of the effector kinase Chk1 by ATR. However, Claspin also performs other roles related to the protection and maintenance of cell and genome integrity. For instance, following DNA damage and checkpoint activation, Claspin bridges checkpoint responses to DNA repair or to apoptosis. During DNA replication, Claspin acts a sensor and couples DNA unwinding to strand polymerization, and may also indirectly regulate replication initiation at firing origins. As Claspin participates in several processes that are vital to maintenance of cell homeostasis, its function is tightly regulated at multiple levels. Nevertheless, little is known about its role in cancer. Accumulating evidence suggests that Claspin inactivation could be an essential event during carcinogenesis, indicating that Claspin may function as a tumour suppressor. In this review, we will examine the functions of Claspin and how its deregulation may contribute to cancer initiation and progression. To conclude, we will discuss means by which Claspin can be targeted for cancer therapy.
Collapse
Affiliation(s)
- Diana Azenha
- Faculdade de Farmácia da Universidade de Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; Centro de Neurociências e Biologia Celular, Universidade de Coimbra, Rua Larga, Faculdade de Medicina, Pólo I, 1º andar, 3004-504 Coimbra, Portugal; Instituto Português de Oncologia de Coimbra de Francisco Gentil, Av. Bissaya Barreto 98, Apartado 2005, 3000-651, Coimbra, Portugal.
| | - Maria Celeste Lopes
- Faculdade de Farmácia da Universidade de Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; Centro de Neurociências e Biologia Celular, Universidade de Coimbra, Rua Larga, Faculdade de Medicina, Pólo I, 1º andar, 3004-504 Coimbra, Portugal.
| | - Teresa C Martins
- Centro de Neurociências e Biologia Celular, Universidade de Coimbra, Rua Larga, Faculdade de Medicina, Pólo I, 1º andar, 3004-504 Coimbra, Portugal; Instituto Português de Oncologia de Coimbra de Francisco Gentil, Av. Bissaya Barreto 98, Apartado 2005, 3000-651, Coimbra, Portugal.
| |
Collapse
|
42
|
Foreman HCC, Armstrong J, Santana AL, Krug LT, Reich NC. The replication and transcription activator of murine gammaherpesvirus 68 cooperatively enhances cytokine-activated, STAT3-mediated gene expression. J Biol Chem 2017; 292:16257-16266. [PMID: 28821622 DOI: 10.1074/jbc.m117.786970] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 08/04/2017] [Indexed: 12/15/2022] Open
Abstract
Gammaherpesviruses (γHVs) have a dynamic strategy for lifelong persistence, involving productive infection, latency, and intermittent reactivation. In latency reservoirs, such as B lymphocytes, γHVs exist as viral episomes and express few viral genes. Although the ability of γHV to reactivate from latency and re-enter the lytic phase is challenging to investigate and control, it is known that the γHV replication and transcription activator (RTA) can promote lytic reactivation. In this study, we provide first evidence that RTA of murine γΗV68 (MHV68) selectively binds and enhances the activity of tyrosine-phosphorylated host STAT3. STAT3 is a transcription factor classically activated by specific tyrosine 705 phosphorylation (pTyr705-STAT3) in response to cytokine stimulation. pTyr705-STAT3 forms a dimer that avidly binds a consensus target site in the promoters of regulated genes, and our results indicate that RTA cooperatively enhances the ability of pTyr705-STAT3 to induce expression of a STAT3-responsive reporter gene. As indicated by coimmunoprecipitation, in latently infected B cells that are stimulated to reactivate MHV68, RTA bound specifically to endogenous pTyr705-STAT3. An in vitro binding assay confirmed that RTA selectively recognizes pTyr705-STAT3 and indicated that the C-terminal transactivation domain of RTA was required for enhancing STAT3-directed gene expression. The cooperation of these transcription factors may influence both viral and host genes. During MHV68 de novo infection, pTyr705-STAT3 promoted the temporal expression of ORF59, a viral replication protein. Our results demonstrate that MHV68 RTA specifically recognizes and recruits activated pTyr705-STAT3 during the lytic phase of infection.
Collapse
Affiliation(s)
- Hui-Chen Chang Foreman
- From the Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11794
| | - Julie Armstrong
- From the Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11794
| | - Alexis L Santana
- From the Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11794
| | - Laurie T Krug
- From the Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11794
| | - Nancy C Reich
- From the Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11794
| |
Collapse
|
43
|
Hafez AY, Messinger JE, McFadden K, Fenyofalvi G, Shepard CN, Lenzi GM, Kim B, Luftig MA. Limited nucleotide pools restrict Epstein-Barr virus-mediated B-cell immortalization. Oncogenesis 2017; 6:e349. [PMID: 28604764 PMCID: PMC5519195 DOI: 10.1038/oncsis.2017.46] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 04/20/2017] [Indexed: 12/18/2022] Open
Abstract
Activation of cellular oncogenes as well as infection with tumor viruses can promote aberrant proliferation and activation of the host DNA damage response. Epstein-Barr virus (EBV) infection of primary human B cells induces a transient period of hyper-proliferation, but many of these infected cells succumb to an ataxia telangiectasia mutated/checkpoint kinase 2 (ATM/Chk2)-mediated senescence-like growth arrest. In this study, we assessed the role of DNA replicative stress and nucleotide pool levels in limiting EBV-infected B-cell outgrowth. We found that EBV triggered activation of the ataxia telangiectasia and Rad3-related (ATR) signaling pathway in the early rapidly proliferating cells, which were also significantly more sensitive to inhibition of the ATR pathway than late attenuated proliferating cells. Through nuclear halo assays, we determined that early EBV-infected cells displayed increased replicative stress and DNA damage relative to late proliferating cells. Finally, we found that early after infection, hyper-proliferating B cells exhibited limited deoxyribonucleotide triphosphate (dNTP) pools compared with late proliferating and EBV-immortalized lymphoblastoid cell lines with a specific loss of purine dNTPs. Importantly, supplementation with exogenous nucleosides before the period of hyper-proliferation markedly enhanced B-cell immortalization by EBV and rescued replicative stress. Together our results suggest that purine dNTP biosynthesis has a critical role in the early stages of EBV-mediated B-cell immortalization.
Collapse
Affiliation(s)
- A Y Hafez
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC, USA
| | - J E Messinger
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC, USA
| | - K McFadden
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC, USA
| | - G Fenyofalvi
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC, USA
| | - C N Shepard
- Department of Pediatrics, Center for Drug Discovery, School of Medicine, Emory University, Atlanta, GA, USA
| | - G M Lenzi
- Department of Pediatrics, Center for Drug Discovery, School of Medicine, Emory University, Atlanta, GA, USA
| | - B Kim
- Department of Pediatrics, Center for Drug Discovery, School of Medicine, Emory University, Atlanta, GA, USA
| | - M A Luftig
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC, USA
| |
Collapse
|
44
|
Epstein-Barr virus-induced up-regulation of TCAB1 is involved in the DNA damage response in nasopharyngeal carcinoma. Sci Rep 2017; 7:3218. [PMID: 28607398 PMCID: PMC5468285 DOI: 10.1038/s41598-017-03156-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 04/25/2017] [Indexed: 02/05/2023] Open
Abstract
Telomerase Cajal body protein 1 (TCAB1), which is involved in Cajal body maintenance, telomere elongation and ribonucleoprotein biogenesis, has been linked to cancer predisposition, including nasopharyngeal carcinoma (NPC), due to its oncogenic properties. However, there are no specific reports to date on the functional relevance of TCAB1 and Epstein–Barr virus (EBV), which is considered to be a risk factor for NPC. In this study, we first examined NPC clinical tissues and found a notable overexpression of TCAB1 in EBV-positive specimens. Secondly, on a cellular level, we also observed that TCAB1 expression rose gradually along with the increased duration of EBV exposure in NPC cell lines. Additionally, EBV infection promoted cell proliferation and telomerase activity, but the activation was significantly inhibited after TCAB1 knockdown. Moreover, depletion of TCAB1 caused both cell cycle arrest and apoptosis, and suppressed the activation of ataxia telangiectasia and Rad3 related protein (ATR) induced by EBV, resulting in accumulation of DNA damage. Taken together, we here demonstrate that up-regulated expression of TCAB1, induced by EBV in the development of NPC, is involved in stimulating telomerase activity and regulating the DNA damage response within the context of EBV infection.
Collapse
|
45
|
García V, Lara-Chica M, Cantarero I, Sterner O, Calzado MA, Muñoz E. Galiellalactone induces cell cycle arrest and apoptosis through the ATM/ATR pathway in prostate cancer cells. Oncotarget 2016; 7:4490-506. [PMID: 26683224 PMCID: PMC4826221 DOI: 10.18632/oncotarget.6606] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 11/26/2015] [Indexed: 12/14/2022] Open
Abstract
Galiellalactone (GL) is a fungal metabolite that presents antitumor activities on prostate cancer in vitro and in vivo. In this study we show that GL induced cell cycle arrest in G2/M phase, caspase-dependent apoptosis and also affected the microtubule organization and migration ability in DU145 cells. GL did not induce double strand DNA break but activated the ATR and ATM-mediated DNA damage response (DDR) inducing CHK1, H2AX phosphorylation (fH2AX) and CDC25C downregulation. Inhibition of the ATM/ATR activation with caffeine reverted GL-induced G2/M cell cycle arrest, apoptosis and DNA damage measured by fH2AX. In contrast, UCN-01, a CHK1 inhibitor, prevented GL-induced cell cycle arrest but enhanced apoptosis in DU145 cells. Furthermore, we found that GL did not increase the levels of intracellular ROS, but the antioxidant N-acetylcysteine (NAC) completely prevented the effects of GL on fH2AX, G2/M cell cycle arrest and apoptosis. In contrast to NAC, other antioxidants such as ambroxol and EGCG did not interfere with the activity of GL on cell cycle. GL significantly suppressed DU145 xenograft growth in vivo and induced the expression of fH2AX in the tumors. These findings identify for the first time that GL activates DDR in prostate cancer.
Collapse
Affiliation(s)
- Víctor García
- Maimónides Biomedical Research Institute of Córdoba, Reina Sofía University Hospital, Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
| | - Maribel Lara-Chica
- Maimónides Biomedical Research Institute of Córdoba, Reina Sofía University Hospital, Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
| | - Irene Cantarero
- Maimónides Biomedical Research Institute of Córdoba, Reina Sofía University Hospital, Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
| | - Olov Sterner
- Department of Science, Centre for Analysis and Synthesis, Lund University, Lund, Sweden
| | - Marco A Calzado
- Maimónides Biomedical Research Institute of Córdoba, Reina Sofía University Hospital, Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
| | - Eduardo Muñoz
- Maimónides Biomedical Research Institute of Córdoba, Reina Sofía University Hospital, Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
| |
Collapse
|
46
|
Abstract
A challenging property of gammaherpesviruses is their ability to establish lifelong persistence. The establishment of latency in B cells is thought to involve active virus engagement of host signaling pathways. Pathogenic effects of these viruses during latency or following reactivation can be devastating to the host. Many cancers, including those associated with members of the gammaherpesvirus family, Kaposi’s sarcoma-associated herpesvirus and Epstein-Barr virus, express elevated levels of active host signal transducer and activator of transcription-3 (STAT3). STAT3 is activated by tyrosine phosphorylation in response to many cytokines and can orchestrate effector responses that include proliferation, inflammation, metastasis, and developmental programming. However, the contribution of STAT3 to gammaherpesvirus pathogenesis remains to be completely understood. This is the first study to have identified STAT3 as a critical host determinant of the ability of gammaherpesvirus to establish long-term latency in an animal model of disease. Following an acute infection, murine gammaherpesvirus 68 (MHV68) established latency in resident B cells, but establishment of latency was dramatically reduced in animals with a B cell-specific STAT3 deletion. The lack of STAT3 in B cells did not impair germinal center responses for immunoglobulin (Ig) class switching in the spleen and did not reduce either total or virus-specific IgG titers. Although ablation of STAT3 in B cells did not have a global effect on these assays of B cell function, it had long-term consequences for the viral load of the host, since virus latency was reduced at 6 to 8 weeks postinfection. Our findings establish host STAT3 as a mediator of gammaherpesvirus persistence. The insidious ability of gammaherpesviruses to establish latent infections can have detrimental consequences for the host. Identification of host factors that promote viral latency is essential for understanding latency mechanisms and for therapeutic interventions. We provide the first evidence that STAT3 expression is needed for murine gammaherpesvirus 68 to establish latency in primary B cells during an active immune response to infection. STAT3 deletion in B cells does not impair adaptive immune control of the virus, but loss of STAT3 in B cells has a long-lasting impact on viral persistence. These results indicate a potential therapeutic benefit of STAT3 inhibitors for combating gammaherpesvirus latency and, thereby, associated pathologies.
Collapse
|
47
|
Li X, Bhaduri-McIntosh S. A Central Role for STAT3 in Gammaherpesvirus-Life Cycle and -Diseases. Front Microbiol 2016; 7:1052. [PMID: 27458446 PMCID: PMC4937026 DOI: 10.3389/fmicb.2016.01052] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 06/23/2016] [Indexed: 12/14/2022] Open
Abstract
Having co-evolved with humans, herpesviruses have adapted to exploit the host molecular machinery to ensure viral persistence. The cellular protein Signal Transducer and Activator of Transcription 3 (STAT3) is a leading example. STAT3 is a prominent transcription factor that functions in a variety of physiologic processes including embryonic development, inflammation, immunity, and wound healing. Generally activated via growth factor and cytokine signaling, STAT3 can transcriptionally drive oncoproteins, pro-survival and pro-proliferative proteins as well as angiogenic factors, thereby contributing to cancer. As in most non-viral cancers, STAT3 is constitutively active in EBV-related B and epithelial cell cancers and in animal models of KSHV-cancers. Again, similar to non-viral cancers, STAT3 contributes to gammaherpesvirus (EBV and KSHV)-mediated cancers by driving cell proliferation, invasion and angiogenesis. Being herpesviruses, EBV and KSHV establish latency in humans with episodic lytic activation. Importantly, both viruses activate STAT3 almost immediately upon infection of primary cells. In the setting of infection of primary B cells by EBV, this rapidly activated STAT3 plays a key role in suppressing the DNA damage response (DDR) to EBV-oncogene triggered replication stress, thereby facilitating B cell proliferation and ultimately establishment of latency. STAT3 also contributes to maintenance of latency by curbing lytic activation of EBV and KSHV in latent cells that express high levels of STAT3. In this way, gammaherpesviruses exploit STAT3 to overcome cellular anti-proliferative and anti-lytic barriers to promote viral persistence. These investigations into gammaherpesviruses and STAT3 have simultaneously revealed a novel function for STAT3 in suppression of the DDR, a process fundamental to physiologic cell proliferation as well as development of cancer.
Collapse
Affiliation(s)
- Xiaofan Li
- Pediatric Infectious Diseases, Department of Pediatrics, Stony Brook University School of Medicine Stony Brook, NY, USA
| | - Sumita Bhaduri-McIntosh
- Pediatric Infectious Diseases, Department of Pediatrics, Stony Brook University School of MedicineStony Brook, NY, USA; Department of Molecular Genetics and Microbiology, Stony Brook University School of MedicineStony Brook, NY, USA
| |
Collapse
|
48
|
Li R, Liao G, Nirujogi RS, Pinto SM, Shaw PG, Huang TC, Wan J, Qian J, Gowda H, Wu X, Lv DW, Zhang K, Manda SS, Pandey A, Hayward SD. Phosphoproteomic Profiling Reveals Epstein-Barr Virus Protein Kinase Integration of DNA Damage Response and Mitotic Signaling. PLoS Pathog 2015; 11:e1005346. [PMID: 26714015 PMCID: PMC4699913 DOI: 10.1371/journal.ppat.1005346] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 11/28/2015] [Indexed: 12/21/2022] Open
Abstract
Epstein-Barr virus (EBV) is etiologically linked to infectious mononucleosis and several human cancers. EBV encodes a conserved protein kinase BGLF4 that plays a key role in the viral life cycle. To provide new insight into the host proteins regulated by BGLF4, we utilized stable isotope labeling by amino acids in cell culture (SILAC)-based quantitative proteomics to compare site-specific phosphorylation in BGLF4-expressing Akata B cells. Our analysis revealed BGLF4-mediated hyperphosphorylation of 3,046 unique sites corresponding to 1,328 proteins. Frequency analysis of these phosphosites revealed a proline-rich motif signature downstream of BGLF4, indicating a broader substrate recognition for BGLF4 than its cellular ortholog cyclin-dependent kinase 1 (CDK1). Further, motif analysis of the hyperphosphorylated sites revealed enrichment in ATM, ATR and Aurora kinase substrates while functional analyses revealed significant enrichment of pathways related to the DNA damage response (DDR), mitosis and cell cycle. Phosphorylation of proteins associated with the mitotic spindle assembly checkpoint (SAC) indicated checkpoint activation, an event that inactivates the anaphase promoting complex/cyclosome, APC/C. Furthermore, we demonstrated that BGLF4 binds to and directly phosphorylates the key cellular proteins PP1, MPS1 and CDC20 that lie upstream of SAC activation and APC/C inhibition. Consistent with APC/C inactivation, we found that BGLF4 stabilizes the expression of many known APC/C substrates. We also noted hyperphosphorylation of 22 proteins associated the nuclear pore complex, which may contribute to nuclear pore disassembly and SAC activation. A drug that inhibits mitotic checkpoint activation also suppressed the accumulation of extracellular EBV virus. Taken together, our data reveal that, in addition to the DDR, manipulation of mitotic kinase signaling and SAC activation are mechanisms associated with lytic EBV replication. All MS data have been deposited in the ProteomeXchange with identifier PXD002411 (http://proteomecentral.proteomexchange.org/dataset/PXD002411). Epstein-Barr virus (EBV) is a herpesvirus that is associated with B cell and epithelial human cancers. Herpesviruses encode a protein kinase which is an important regulator of lytic virus replication and is consequently a target for anti-viral drug development. The EBV genome encodes for a serine/threonine protein kinase called BGLF4. Previous work on BGLF4 has largely focused on its cyclin-dependent kinase 1 (CDK1)-like activity. The range of BGLF4 cellular substrates and the full impact of BGLF4 on the intracellular microenvironment still remain to be elucidated. Here, we utilized unbiased quantitative phosphoproteomic approach to dissect the changes in the cellular phosphoproteome that are mediated by BGLF4. Our MS analyses revealed extensive hyperphosphorylation of substrates that are normally targeted by CDK1, Ataxia telangiectasia mutated (ATM), Ataxia telangiectasia and Rad3-related (ATR) proteins and Aurora kinases. The up-regulated phosphoproteins were functionally linked to the DNA damage response, mitosis and cell cycle pathways. Our data demonstrate widespread changes in the cellular phosphoproteome that occur upon BGLF4 expression and suggest that manipulation of the DNA damage and mitotic kinase signaling pathways are central to efficient EBV lytic replication.
Collapse
Affiliation(s)
- Renfeng Li
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Philips Institute for Oral Health Research, VCU School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
- Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia, United States of America
- * E-mail: (RL); (AP); (SDH)
| | - Gangling Liao
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Raja Sekhar Nirujogi
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Institute of Bioinformatics, International Technology Park, Bangalore, India
| | - Sneha M. Pinto
- Institute of Bioinformatics, International Technology Park, Bangalore, India
| | - Patrick G. Shaw
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Tai-Chung Huang
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jun Wan
- Wilmer Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jiang Qian
- Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Harsha Gowda
- Institute of Bioinformatics, International Technology Park, Bangalore, India
| | - Xinyan Wu
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Dong-Wen Lv
- Philips Institute for Oral Health Research, VCU School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Kun Zhang
- Philips Institute for Oral Health Research, VCU School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Srikanth S. Manda
- Philips Institute for Oral Health Research, VCU School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Akhilesh Pandey
- Philips Institute for Oral Health Research, VCU School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Diana Helis Henry Medical Research Foundation, New Orleans, Louisiana, United States of America
- * E-mail: (RL); (AP); (SDH)
| | - S. Diane Hayward
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (RL); (AP); (SDH)
| |
Collapse
|
49
|
Oxidative stress enables Epstein-Barr virus-induced B-cell transformation by posttranscriptional regulation of viral and cellular growth-promoting factors. Oncogene 2015; 35:3807-16. [PMID: 26592445 DOI: 10.1038/onc.2015.450] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 10/14/2015] [Accepted: 10/22/2015] [Indexed: 12/13/2022]
Abstract
Infection of human B lymphocytes by Epstein-Barr virus (EBV) leads to the establishment of immortalized lymphoblastoid cell lines (LCLs) that are widely used as a model of viral oncogenesis. An early consequence of infection is the induction of DNA damage and activation of the DNA damage response, which limits the efficiency of growth transformation. The cause of the DNA damage remains poorly understood. We have addressed this question by comparing the response of B lymphocytes infected with EBV or stimulated with a potent B-cell mitogen. We found that although the two stimuli induce comparable proliferation during the first 10 days of culture, the EBV-infected blasts showed significantly higher levels of DNA damage, which correlated with stronger and sustained accumulation of reactive oxygen species (ROS). Treatment with ROS scavengers decreased DNA damage in both mitogen-stimulated and EBV-infected cells. However, while mitogen-induced proliferation was slightly improved, the proliferation of EBV-infected cells and the establishment of LCLs were severely impaired. Quenching of ROS did not affect the kinetics and magnitude of viral gene expression but was associated with selective downregulation of the viral LMP1 and phosphorylated cellular transcription factor STAT3 that have key roles in transformation. Analysis of the mechanism by which high levels of ROS support LMP1 expression revealed selective inhibition of viral microRNAs that target the LMP1 transcript. Our study provides novel insights into the role of EBV-induced oxidative stress in promoting B-cell immortalization and malignant transformation.
Collapse
|
50
|
Liao XH, Zheng L, He HP, Zheng DL, Wei ZQ, Wang N, Dong J, Ma WJ, Zhang TC. STAT3 regulated ATR via microRNA-383 to control DNA damage to affect apoptosis in A431 cells. Cell Signal 2015; 27:2285-95. [DOI: 10.1016/j.cellsig.2015.08.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/05/2015] [Indexed: 10/24/2022]
|