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Washif M, Kawasumi R, Hirota K. REV3 promotes cellular tolerance to 5-fluorodeoxyuridine by activating translesion DNA synthesis and intra-S checkpoint. PLoS Genet 2024; 20:e1011341. [PMID: 38954736 PMCID: PMC11249241 DOI: 10.1371/journal.pgen.1011341] [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: 02/15/2024] [Revised: 07/15/2024] [Accepted: 06/13/2024] [Indexed: 07/04/2024] Open
Abstract
The drug floxuridine (5-fluorodeoxyuridine, FUdR) is an active metabolite of 5-Fluorouracil (5-FU). It converts to 5-fluorodeoxyuridine monophosphate (FdUMP) and 5-fluorodeoxyuridine triphosphate (FdUTP), which on incorporation into the genome inhibits DNA replication. Additionally, it inhibits thymidylate synthase, causing dTMP shortage while increasing dUMP availability, which induces uracil incorporation into the genome. However, the mechanisms underlying cellular tolerance to FUdR are yet to be fully elucidated. In this study, we explored the mechanisms underlying cellular resistance to FUdR by screening for FUdR hypersensitive mutants from a collection of DT40 mutants deficient in each genomic maintenance system. We identified REV3, which is involved in translesion DNA synthesis (TLS), to be a critical factor in FUdR tolerance. Replication using a FUdR-damaged template was attenuated in REV3-/- cells, indicating that the TLS function of REV3 is required to maintain replication on the FUdR-damaged template. Notably, FUdR-exposed REV3-/- cells exhibited defective cell cycle arrest in the early S phase, suggesting that REV3 is involved in intra-S checkpoint activation. Furthermore, REV3-/- cells showed defects in Chk1 phosphorylation, which is required for checkpoint activation, but the survival of FUdR-exposed REV3-/- cells was further reduced by the inhibition of Chk1 or ATR. These data indicate that REV3 mediates DNA checkpoint activation at least through Chk1 phosphorylation, but this signal acts in parallel with ATR-Chk1 DNA damage checkpoint pathway. Collectively, we reveal a previously unappreciated role of REV3 in FUdR tolerance.
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Affiliation(s)
- Mubasshir Washif
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Tokyo, Japan
| | - Ryotaro Kawasumi
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Tokyo, Japan
| | - Kouji Hirota
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Tokyo, Japan
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2
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Liu HL, Peng H, Huang CH, Zhou HY, Ge J. Mutational separation and clinical outcomes of TP53 and CDH1 in gastric cancer. World J Gastrointest Surg 2023; 15:2855-2865. [PMID: 38222005 PMCID: PMC10784822 DOI: 10.4240/wjgs.v15.i12.2855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/18/2023] [Accepted: 11/21/2023] [Indexed: 12/27/2023] Open
Abstract
BACKGROUND Gastric cancer (GC) is a deadly tumor with the fifth highest occurrence and highest global mortality rates. Owing to its heterogeneity, the underlying mechanism of GC remains unclear, and chemotherapy offers little benefit to individuals. AIM To investigate the clinical outcomes of TP53 and CDH1 mutations in GC. METHODS In this study, 202 gastric adenocarcinoma tumor tissues and their corresponding normal tissues were collected. A total of 490 genes were identified using target capture. Through t-test and Wilcoxon rank-sum test, somatic mutations, microsatellite instability, and clinical statistics, including overall survival, were detected, compared, and calculated. RESULTS The mutation rates of 32 genes, including TP53, SPEN, FAT1, and CDH1 exceeded 10%. TP53 mutations had a slightly lower overall occurrence rate (33%). The TP53 mutation rate was significantly higher in advanced stages (stage III/IV) than that in early stages (stage I/II) (P < 0.05). In contrast, CDH1 mutations were significantly associated with diffuse GC. TP53 is related to poor prognosis of advanced-stage tumors; nevertheless, CDH1 corresponds to a diffuse type of cancer. TP53 is exclusively mutated in CDH1 and is primarily affected by two distinct GC mechanisms. CONCLUSION Different somatic mutation patterns in TP53 and CDH1 indicate two major mechanisms of GC.
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Affiliation(s)
- He-Li Liu
- Department of Gastrointestinal Surgery, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China
| | - Huan Peng
- Clinical Nursing Teaching and Research Section, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China
| | - Chang-Hao Huang
- Teaching and Research Section of Clinical Nursing, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China
| | - Hai-Yan Zhou
- Department of Pathology, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China
| | - Jie Ge
- Department of Gastrointestinal Surgery, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China
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3
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Guan J, Li GM. DNA mismatch repair in cancer immunotherapy. NAR Cancer 2023; 5:zcad031. [PMID: 37325548 PMCID: PMC10262306 DOI: 10.1093/narcan/zcad031] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/08/2023] [Accepted: 06/07/2023] [Indexed: 06/17/2023] Open
Abstract
Tumors defective in DNA mismatch repair (dMMR) exhibit microsatellite instability (MSI). Currently, patients with dMMR tumors are benefitted from anti-PD-1/PDL1-based immune checkpoint inhibitor (ICI) therapy. Over the past several years, great progress has been made in understanding the mechanisms by which dMMR tumors respond to ICI, including the identification of mutator phenotype-generated neoantigens, cytosolic DNA-mediated activation of the cGAS-STING pathway, type-I interferon signaling and high tumor-infiltration of lymphocytes in dMMR tumors. Although ICI therapy shows great clinical benefits, ∼50% of dMMR tumors are eventually not responsive. Here we review the discovery, development and molecular basis of dMMR-mediated immunotherapy, as well as tumor resistant problems and potential therapeutic interventions to overcome the resistance.
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Affiliation(s)
- Junhong Guan
- Cuiying Biomedical Research Center, Lanzhou University Second Hospital, Lanzhou, Gansu 730030, China
| | - Guo-Min Li
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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Yang H, Huebner K, Hampel C, Erlenbach-Wuensch K, Selvamani SB, Shukla V, Geppert CI, Hartmann A, Mahadevan V, Schneider-Stock R. ATF2 loss promotes 5-FU resistance in colon cancer cells via activation of the ATR-Chk1 damage response pathway. BMC Cancer 2023; 23:480. [PMID: 37237279 DOI: 10.1186/s12885-023-10940-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
BACKGROUND The role of ATF2 in colon cancer (CC) is controversial. Recently, we reported that low ATF2 expression is characteristic of highly invasive tumors, suggesting that ATF2 might also be involved in therapy resistance. 5-Fluorouracil (5-FU) is the best-known chemotherapeutic drug for CC, but drug resistance affects its curative effect. To date, the role of ATF2 in the 5-FU response remains elusive. METHODS/RESULTS For our study, we had available HCT116 cells (wild-type p53) and HT29 colon tumor cells (mutant p53) and their corresponding CRISPR‒Cas9-generated ATF2-KO clones. We observed that loss of ATF2 triggered dose- and time-dependent 5-FU resistance in HCT116 cells by activating the DNA damage response (DDR) pathway with high p-ATRThr1989 and p-Chk1Ser317 levels accompanied by an increase in the DNA damage marker γ-H2AX in vitro and in vivo using the chicken chorioallantoic membrane (CAM) model. Chk1 inhibitor studies causally displayed the link between DDR and drug resistance. There were contradictory findings in HT29 ATF2-KO cells upon 5-FU exposure with low p-Chk1Ser317 levels, strong apoptosis induction, but no effects on DNA damage. In ATF2-silenced HCT116 p53-/- cells, 5-FU did not activate the DDR pathway. Co-immunoprecipitation and proximity ligation assays revealed that upon 5-FU treatment, ATF2 binds to ATR to prevent Chk1 phosphorylation. Indeed, in silico modelling showed reduced ATR-Chk1 binding when ATF2 was docked into the complex. CONCLUSIONS We demonstrated a novel ATF2 scaffold function involved in the DDR pathway. ATF2-negative cells are highly resistant due to effective ATR/Chk1 DNA damage repair. Mutant p53 seems to overwrite the tumor suppressor function of ATF2.
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Affiliation(s)
- Hao Yang
- Experimental Tumorpathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Universitätsstr. 22, 91504, Erlangen, Germany
- Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Krankenhausstr. 8-10, Erlangen, 91504, Germany
| | - Kerstin Huebner
- Experimental Tumorpathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Universitätsstr. 22, 91504, Erlangen, Germany
- Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Krankenhausstr. 8-10, Erlangen, 91504, Germany
| | - Chuanpit Hampel
- Experimental Tumorpathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Universitätsstr. 22, 91504, Erlangen, Germany
- Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Krankenhausstr. 8-10, Erlangen, 91504, Germany
| | - Katharina Erlenbach-Wuensch
- Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Krankenhausstr. 8-10, Erlangen, 91504, Germany
| | - Selva Babu Selvamani
- Institute of Bioinformatics and Applied Biotechnology (IBAB), Bangalore, 560100, India
| | - Vikas Shukla
- Institute of Bioinformatics and Applied Biotechnology (IBAB), Bangalore, 560100, India
| | - Carol I Geppert
- Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Krankenhausstr. 8-10, Erlangen, 91504, Germany
| | - Arndt Hartmann
- Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Krankenhausstr. 8-10, Erlangen, 91504, Germany
- Comprehensive Cancer Center Erlangen‑EMN (CCC ER‑EMN), Östliche Stadtmauerstr. 30, Erlangen, 91054, Germany
| | | | - Regine Schneider-Stock
- Experimental Tumorpathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Universitätsstr. 22, 91504, Erlangen, Germany.
- Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Krankenhausstr. 8-10, Erlangen, 91504, Germany.
- Comprehensive Cancer Center Erlangen‑EMN (CCC ER‑EMN), Östliche Stadtmauerstr. 30, Erlangen, 91054, Germany.
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Immunosuppressive Signaling Pathways as Targeted Cancer Therapies. Biomedicines 2022. [DOI: 10.3390/biomedicines10030682
expr 829797163 + 949875436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Immune response has been shown to play an important role in defining patient prognosis and response to cancer treatment. Tumor-induced immunosuppression encouraged the recent development of new chemotherapeutic agents that assists in the augmentation of immune responses. Molecular mechanisms that tumors use to evade immunosurveillance are attributed to their ability to alter antigen processing/presentation pathways and the tumor microenvironment. Cancer cells take advantage of normal molecular and immunoregulatory machinery to survive and thrive. Cancer cells constantly adjust their genetic makeup using several mechanisms such as nucleotide excision repair as well as microsatellite and chromosomal instability, thus giving rise to new variants with reduced immunogenicity and the ability to continue to grow without restrictions. This review will focus on the central molecular signaling pathways involved in immunosuppressive cells and briefly discuss how cancer cells evade immunosurveillance by manipulating antigen processing cells and related proteins. Secondly, the review will discuss how these pathways can be utilized for the implementation of precision medicine and deciphering drug resistance.
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6
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Setlai BP, Hull R, Bida M, Durandt C, Mulaudzi TV, Chatziioannou A, Dlamini Z. Immunosuppressive Signaling Pathways as Targeted Cancer Therapies. Biomedicines 2022; 10:682. [PMID: 35327484 PMCID: PMC8945019 DOI: 10.3390/biomedicines10030682] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/08/2022] [Accepted: 03/11/2022] [Indexed: 12/23/2022] Open
Abstract
Immune response has been shown to play an important role in defining patient prognosis and response to cancer treatment. Tumor-induced immunosuppression encouraged the recent development of new chemotherapeutic agents that assists in the augmentation of immune responses. Molecular mechanisms that tumors use to evade immunosurveillance are attributed to their ability to alter antigen processing/presentation pathways and the tumor microenvironment. Cancer cells take advantage of normal molecular and immunoregulatory machinery to survive and thrive. Cancer cells constantly adjust their genetic makeup using several mechanisms such as nucleotide excision repair as well as microsatellite and chromosomal instability, thus giving rise to new variants with reduced immunogenicity and the ability to continue to grow without restrictions. This review will focus on the central molecular signaling pathways involved in immunosuppressive cells and briefly discuss how cancer cells evade immunosurveillance by manipulating antigen processing cells and related proteins. Secondly, the review will discuss how these pathways can be utilized for the implementation of precision medicine and deciphering drug resistance.
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Affiliation(s)
- Botle Precious Setlai
- Department of Surgery, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Arcadia 0007, South Africa;
| | - Rodney Hull
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Hatfield 0028, South Africa;
| | - Meshack Bida
- Department of Anatomical Pathology, National Health Laboratory Service (NHLS), University of Pretoria, Hatfield 0028, South Africa;
| | - Chrisna Durandt
- Institute for Cellular and Molecular Medicine, Department of Immunology, SAMRC Extramural Unit for Stem Cell Research and Therapy, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa;
| | - Thanyani Victor Mulaudzi
- Department of Surgery, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Arcadia 0007, South Africa;
| | - Aristotelis Chatziioannou
- Center of Systems Biology, Biomedical Research Foundation Academy of Athens, 4 Soranou Ephessiou Str., 115 27 Athens, Greece;
| | - Zodwa Dlamini
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Hatfield 0028, South Africa;
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7
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Guan J, Lu C, Jin Q, Lu H, Chen X, Tian L, Zhang Y, Ortega J, Zhang J, Siteni S, Chen M, Gu L, Shay JW, Davis AJ, Chen ZJ, Fu YX, Li GM. MLH1 Deficiency-Triggered DNA Hyperexcision by Exonuclease 1 Activates the cGAS-STING Pathway. Cancer Cell 2021; 39:109-121.e5. [PMID: 33338427 PMCID: PMC8666006 DOI: 10.1016/j.ccell.2020.11.004] [Citation(s) in RCA: 147] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 09/22/2020] [Accepted: 11/13/2020] [Indexed: 12/15/2022]
Abstract
Tumors with defective mismatch repair (dMMR) are responsive to immunotherapy because of dMMR-induced neoantigens and activation of the cGAS-STING pathway. While neoantigens result from the hypermutable nature of dMMR, it is unknown how dMMR activates the cGAS-STING pathway. We show here that loss of the MutLα subunit MLH1, whose defect is responsible for ~50% of dMMR cancers, results in loss of MutLα-specific regulation of exonuclease 1 (Exo1) during DNA repair. This leads to unrestrained DNA excision by Exo1, which causes increased single-strand DNA formation, RPA exhaustion, DNA breaks, and aberrant DNA repair intermediates. Ultimately, this generates chromosomal abnormalities and the release of nuclear DNA into the cytoplasm, activating the cGAS-STING pathway. In this study, we discovered a hitherto unknown MMR mechanism that modulates genome stability and has implications for cancer therapy.
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Affiliation(s)
- Junhong Guan
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Changzheng Lu
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Qihuang Jin
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Huiming Lu
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Xiang Chen
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lei Tian
- Department of Cancer Biology, Basser Center for BRCA, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yanbin Zhang
- Department of Biochemistry & Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Janice Ortega
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Junqiu Zhang
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Silvia Siteni
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Mingyi Chen
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Liya Gu
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jerry W Shay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Anthony J Davis
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Zhijian J Chen
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yang-Xin Fu
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Guo-Min Li
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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8
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Tong C, Qu K, Wang G, Liu R, Duan B, Wang X, Liu C. Knockdown of DNA-binding protein A enhances the chemotherapy sensitivity of colorectal cancer via suppressing the Wnt/β-catenin/Chk1 pathway. Cell Biol Int 2020; 44:2075-2085. [PMID: 32652867 DOI: 10.1002/cbin.11416] [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: 06/04/2020] [Revised: 06/18/2020] [Accepted: 07/05/2020] [Indexed: 11/07/2022]
Abstract
DNA-binding protein A (dbpA) is reported to be upregulated in many cancers and associated with tumor progress. The present study aimed to investigate the role of dbpA in 5-fluorouracil (5-FU)-resistant and oxaliplatin (L-OHP)-resistant colorectal cancer (CRC) cells. We found that 5-FU and L-OPH treatment promoted the expression of dbpA. Enhanced dbpA promoted the drug resistance of SW620 cells to 5-FU and L-OHP. DbpA knockdown inhibited cell proliferation, induced cell apoptosis, and cell cycle arrested in SW620/5-FU and SW620/L-OHP cells. Besides, dbpA short hairpin RNA (shRNA) enhanced the cytotoxicity of 5-FU and L-OHP to SW620/5-FU and SW620/L-OHP cells. Meanwhile, dbpA shRNA inhibited the activation of the Wnt/β-catenin pathway that induced by 5-FU stimulation in SW620/5-FU cells. Activation of the Wnt/β-catenin pathway or overexpression of checkpoint kinase 1 (Chk1) abrogated the promoting effect of dbpA downregulation on 5-FU sensitivity of CRC cells. Importantly, downregulation of dbpA suppressed tumor growth and promoted CRC cells sensitivity to 5-FU in vivo. Our study indicated that the knockdown of dbpA enhanced the sensitivity of CRC cells to 5-FU via Wnt/β-catenin/Chk1 pathway, and DbpA may be a potential therapeutic target to sensitize drug resistance CRC to 5-FU and L-OHP.
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Affiliation(s)
- Cong Tong
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,First Department of General Surgery, Shaanxi Provincial People's Hospital/The Third Affiliated Hospital, College of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Kai Qu
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Guorong Wang
- First Department of General Surgery, Shaanxi Provincial People's Hospital/The Third Affiliated Hospital, College of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Ruiting Liu
- First Department of General Surgery, Shaanxi Provincial People's Hospital/The Third Affiliated Hospital, College of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Baojun Duan
- Department of Oncology, Shaanxi Provincial People's Hospital/The Third Affiliated Hospital, College of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Xiaoqiang Wang
- First Department of General Surgery, Shaanxi Provincial People's Hospital/The Third Affiliated Hospital, College of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Chang Liu
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
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9
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Wang D, Zhao R, Qu YY, Mei XY, Zhang X, Zhou Q, Li Y, Yang SB, Zuo ZG, Chen YM, Lin Y, Xu W, Chen C, Zhao SM, Zhao JY. Colonic Lysine Homocysteinylation Induced by High-Fat Diet Suppresses DNA Damage Repair. Cell Rep 2019; 25:398-412.e6. [PMID: 30304680 DOI: 10.1016/j.celrep.2018.09.022] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 08/15/2018] [Accepted: 09/07/2018] [Indexed: 02/05/2023] Open
Abstract
Colorectal cancer (CRC) onset is profoundly affected by Western diet. Here, we report that high-fat (HF) diet-induced, organ-specific colonic lysine homocysteinylation (K-Hcy) increase might promote CRC onset by impeding DNA damage repair. HF chow induced elevated methionyl-tRNA synthetase (MARS) expression and K-Hcy levels and DNA damage accumulation in the mouse and rat colon, resulting in a phenotype identical to that of CRC tissues. Moreover, the increased copy number of MARS, whose protein product promotes K-Hcy, correlated with increased CRC risk in humans. Mechanistically, MARS preferentially bound to and modified ataxia-telangiectasia and Rad3-related protein (ATR), inhibited ATR and its downstream effectors checkpoint kinase-1 and p53, and relieved cell-cycle arrest and decreased DNA damage-induced apoptosis by disrupting the binding of ATR-interacting protein to ATR. Inhibiting K-Hcy by targeting MARS reversed these effects and suppressed oncogenic CRC cell growth. Our study reveals a mechanism of Western-diet-associated CRC and highlights an intervention approach for reversing diet-induced oncogenic effects.
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Affiliation(s)
- Dan Wang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China; Key Laboratory of Reproduction Regulation of NPFPC, Collaborative Innovation Center for Genetics and Development and Children's Hospital of Fudan University, Shanghai 200438, China; Department of Neonatology and Department of Colorectal Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Rui Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China
| | - Yuan-Yuan Qu
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai 200438, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200438, China
| | - Xin-Yu Mei
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China
| | - Xuan Zhang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China
| | - Qian Zhou
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China
| | - Yang Li
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China
| | - Shao-Bo Yang
- Key Laboratory of Reproduction Regulation of NPFPC, Collaborative Innovation Center for Genetics and Development and Children's Hospital of Fudan University, Shanghai 200438, China
| | - Zhi-Gui Zuo
- Department of Neonatology and Department of Colorectal Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Yi-Ming Chen
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Yan Lin
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China; Key Laboratory of Reproduction Regulation of NPFPC, Collaborative Innovation Center for Genetics and Development and Children's Hospital of Fudan University, Shanghai 200438, China
| | - Wei Xu
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China; Key Laboratory of Reproduction Regulation of NPFPC, Collaborative Innovation Center for Genetics and Development and Children's Hospital of Fudan University, Shanghai 200438, China; Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Chao Chen
- Key Laboratory of Reproduction Regulation of NPFPC, Collaborative Innovation Center for Genetics and Development and Children's Hospital of Fudan University, Shanghai 200438, China
| | - Shi-Min Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China; Key Laboratory of Reproduction Regulation of NPFPC, Collaborative Innovation Center for Genetics and Development and Children's Hospital of Fudan University, Shanghai 200438, China; Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.
| | - Jian-Yuan Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Lab of Genetic Engineering, School of Life Sciences and Institutes of Biomedical Sciences, Shanghai 200438, China; Key Laboratory of Reproduction Regulation of NPFPC, Collaborative Innovation Center for Genetics and Development and Children's Hospital of Fudan University, Shanghai 200438, China; Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.
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10
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Wu M, Li L, Hamaker M, Small D, Duffield AS. FLT3-ITD cooperates with Rac1 to modulate the sensitivity of leukemic cells to chemotherapeutic agents via regulation of DNA repair pathways. Haematologica 2019; 104:2418-2428. [PMID: 30975911 PMCID: PMC6959181 DOI: 10.3324/haematol.2018.208843] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 04/09/2019] [Indexed: 01/01/2023] Open
Abstract
Acute myeloid leukemia (AML) is an aggressive hematologic neoplasm, and patients with an internal tandem duplication (ITD) mutation of the FMS-like tyrosine kinase-3 (FLT3) receptor gene have a poor prognosis. FLT3-ITD interacts with DOCK2, a G effector protein that activates Rac1/2. Previously, we showed that knockdown of DOCK2 leads to decreased survival of FLT3-ITD leukemic cells. We further investigated the mechanisms by which Rac1/DOCK2 activity affects cell survival and chemotherapeutic response in FLT3-ITD leukemic cells. Exogenous expression of FLT3-ITD led to increased Rac1 activity, reactive oxygen species, phosphorylated STAT5, DNA damage response factors and cytarabine resistance. Conversely, DOCK2 knockdown resulted in a decrease in these factors. Consistent with the reduction in DNA damage response factors, FLT3-ITD cells with DOCK2 knockdown exhibited significantly increased sensitivity to DNA damage response inhibitors. Moreover, in a mouse model of FLT3-ITD AML, animals treated with the CHK1 inhibitor MK8776 + cytarabine survived longer than those treated with cytarabine alone. These findings suggest that FLT3-ITD and Rac1 activity cooperatively modulate DNA repair activity, the addition of DNA damage response inhibitors to conventional chemotherapy may be useful in the treatment of FLT3-ITD AML, and inhibition of the Rac signaling pathways via DOCK2 may provide a novel and promising therapeutic target for FLT3-ITD AML.
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Affiliation(s)
| | - Li Li
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins Hospital, Baltimore, Maryland, USA
| | | | - Donald Small
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins Hospital, Baltimore, Maryland, USA
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11
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Mirza-Aghazadeh-Attari M, Darband SG, Kaviani M, Mihanfar A, Aghazadeh Attari J, Yousefi B, Majidinia M. DNA damage response and repair in colorectal cancer: Defects, regulation and therapeutic implications. DNA Repair (Amst) 2018; 69:34-52. [PMID: 30055507 DOI: 10.1016/j.dnarep.2018.07.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/15/2018] [Accepted: 07/15/2018] [Indexed: 12/11/2022]
Abstract
DNA damage response, a key factor involved in maintaining genome integrity and stability, consists of several kinase-dependent signaling pathways, which sense and transduce DNA damage signal. The severity of damage appears to determine DNA damage responses, which can include cell cycle arrest, damage repair and apoptosis. A number of recent studies have demonstrated that defection in signaling through this network is thought to be an underlying mechanism behind the development and progression of various types of human malignancies, including colorectal cancer. In this review, colorectal cancer and its molecular pathology as well as DNA damage response is briefly introduced. Finally, the involvement of key components of this network in the initiation/progression, prognosis, response to treatment and development of drug resistance is comprehensively discussed.
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Affiliation(s)
- Mohammad Mirza-Aghazadeh-Attari
- Aging Research Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saber Ghazizadeh Darband
- Danesh Pey Hadi Co., Health Technology Development Center, Urmia University of Medical Sciences, Urmia, Iran
| | - Mojtaba Kaviani
- School of Nutrition and Dietetics, Acadia University, Wolfville, Nova Scotia, Canada
| | - Ainaz Mihanfar
- Stem Cell and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Bahman Yousefi
- Molecular Medicine Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Maryam Majidinia
- Solid Tumor Research Center, Urmia University of Medical Sciences, Urmia, Iran.
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12
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Chen S, Chen X, Xie G, He Y, Yan D, Zheng D, Li S, Fu X, Li Y, Pang X, Hu Z, Li H, Tan W, Li J. Cdc6 contributes to cisplatin-resistance by activation of ATR-Chk1 pathway in bladder cancer cells. Oncotarget 2018; 7:40362-40376. [PMID: 27246979 PMCID: PMC5130013 DOI: 10.18632/oncotarget.9616] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/08/2016] [Indexed: 12/22/2022] Open
Abstract
High activation of DNA damage response is implicated in cisplatin (CDDP) resistance which presents as a serious obstacle for bladder cancer treatment. Cdc6 plays an important role in the malignant progression of tumor. Here, we reported that Cdc6 expression is up-regulated in bladder cancer tissues and is positively correlated to high tumor grade. Cdc6 depletion can attenuate the malignant properties of bladder cancer cells, including DNA replication, migration and invasion. Furthermore, higher levels of chromatin-binding Cdc6 and ATR were detected in CDDP-resistant bladder cancer cells than in the parent bladder cancer cells. Intriguingly, down-regulation of Cdc6 can enhance sensitivity to CDDP both in bladder cancer cells and CDDP-resistant bladder cancer cells. Cdc6 depletion abrogates S phase arrest caused by CDDP, leading to aberrant mitosis by inactivating ATR-Chk1-Cdc25C pathway. Our results indicate that Cdc6 may be a promising target for overcoming CDDP resistance in bladder cancer.
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Affiliation(s)
- Sansan Chen
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.,Institute of Biotherapy, School of Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
| | - Xinglu Chen
- Institute of Biotherapy, School of Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
| | - Gui'e Xie
- KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yue He
- Institute of Biotherapy, School of Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
| | - Daoyu Yan
- Institute of Biotherapy, School of Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
| | - Dianpeng Zheng
- Institute of Biotherapy, School of Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
| | - Shi Li
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Xinyang Fu
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Yeping Li
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Xiang Pang
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhiming Hu
- Institute of Biotherapy, School of Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
| | - Hongwei Li
- Institute of Biotherapy, School of Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
| | - Wanlong Tan
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Jinlong Li
- Institute of Biotherapy, School of Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
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13
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Li Z, Shao C, Kong Y, Carlock C, Ahmad N, Liu X. DNA Damage Response-Independent Role for MDC1 in Maintaining Genomic Stability. Mol Cell Biol 2017; 37:e00595-16. [PMID: 28193847 PMCID: PMC5394279 DOI: 10.1128/mcb.00595-16] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 12/08/2016] [Accepted: 02/06/2017] [Indexed: 02/04/2023] Open
Abstract
MDC1 is a central player in checkpoint activation and subsequent DNA repair following DNA damage. Although MDC1 has been studied extensively, many of its known functions, to date, pertain to the DNA damage response (DDR) pathway. Herein we report a novel function of phosphorylated MDC1 that is independent of ATM and DNA damage and is required for proper mitotic progression and maintenance of genomic stability. We demonstrate that MDC1 is an in vivo target of Plk1 and that phosphorylated MDC1 is dynamically localized to nuclear envelopes, centrosomes, kinetochores, and midbodies. Knockdown of MDC1 or abrogation of Plk1 phosphorylation of MDC1 causes a delay of the prometaphase-metaphase transition. It is significant that mice with reduced levels of MDC1 showed an elevated level of spontaneous tumors in aged animals. Our results demonstrate that MDC1 also plays a fundamentally significant role in maintenance of genomic stability through a DDR-independent pathway.
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Affiliation(s)
- Zhiguo Li
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, USA
| | - Chen Shao
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, USA
| | - Yifan Kong
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana, USA
| | - Colin Carlock
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, USA
| | - Nihal Ahmad
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin, USA
| | - Xiaoqi Liu
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, USA
- Center for Cancer Research, Purdue University, West Lafayette, Indiana, USA
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14
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Cao X, Lu Y, Zhang X, Kovalovsky D. Zbtb1 Safeguards Genome Integrity and Prevents p53-Mediated Apoptosis in Proliferating Lymphoid Progenitors. THE JOURNAL OF IMMUNOLOGY 2016; 197:1199-211. [PMID: 27402700 DOI: 10.4049/jimmunol.1600013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/07/2016] [Indexed: 12/30/2022]
Abstract
Expression of the transcription factor Zbtb1 is required for normal lymphoid development. We report in the present study that Zbtb1 maintains genome integrity in immune progenitors, without which cells undergo increased DNA damage and p53-mediated apoptosis during replication and differentiation. Increased DNA damage in Zbtb1-mutant (ScanT) progenitors was due to increased sensitivity to replication stress, which was a consequence of inefficient activation of the S-phase checkpoint response. Increased p53-mediated apoptosis affected not only lymphoid but also myeloid development in competitive bone marrow chimeras, and prevention of apoptosis by transgenic Bcl2 expression and p53 deficiency rescued lymphoid as well as myeloid development from Zbtb1-mutant progenitors. Interestingly, however, protection from apoptosis rescued only the early stages of T cell development, and thymocytes remained arrested at the double-negative 3 developmental stage, indicating a strict requirement of Zbtb1 at later T cell developmental stages. Collectively, these results indicate that Zbtb1 prevents DNA damage in replicating immune progenitors, allowing the generation of B cells, T cells, and myeloid cells.
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Affiliation(s)
- Xin Cao
- College of Life Science and Engineering, Northwest University for Nationalities, Lanzhou 730030, China; and Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Ying Lu
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Xianyu Zhang
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Damian Kovalovsky
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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15
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Phase I study of LY2603618, a CHK1 inhibitor, in combination with gemcitabine in Japanese patients with solid tumors. Anticancer Drugs 2015; 26:1043-53. [PMID: 26288133 DOI: 10.1097/cad.0000000000000278] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This phase I trial evaluated LY2603618, a selective inhibitor of the DNA damage checkpoint kinase 1, in combination with gemcitabine. Japanese patients with advanced solid tumors were enrolled. All patients received gemcitabine (1000 mg/m on days 1, 8, and 15 every 28 days) and either 170 mg (cohort 1) or 230 mg (cohort 2) of LY2603618. The primary objective was assessment of safety/tolerability. Pharmacokinetic/pharmacodynamic marker profiles were secondary objectives. Of the 17 patients enrolled, dose-limiting toxicities were observed in one patient in cohort 1 (n=7) and in two patients in cohort 2 (n=10). The most common grade 3 or more drug-related treatment-emergent adverse events were hematological. Three patients discontinued because of adverse events. Dose-dependent decreases in LY2603618 exposure were observed, but the LY2603618 pharmacokinetics at each dose were consistent within and between cycles and did not influence gemcitabine pharmacokinetics. Circulating plasma DNA decreased from baseline in all four patients who achieved a partial response. Administration of 170 or 230 mg of LY2603618 following a standard dose of gemcitabine showed acceptable safety and tolerability in Japanese patients with solid tumors.
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16
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Manic G, Obrist F, Sistigu A, Vitale I. Trial Watch: Targeting ATM-CHK2 and ATR-CHK1 pathways for anticancer therapy. Mol Cell Oncol 2015; 2:e1012976. [PMID: 27308506 PMCID: PMC4905354 DOI: 10.1080/23723556.2015.1012976] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 01/25/2015] [Accepted: 01/26/2015] [Indexed: 02/08/2023]
Abstract
The ataxia telangiectasia mutated serine/threonine kinase (ATM)/checkpoint kinase 2 (CHEK2, best known as CHK2) and the ATM and Rad3-related serine/threonine kinase (ATR)/CHEK1 (best known as CHK1) cascades are the 2 major signaling pathways driving the DNA damage response (DDR), a network of processes crucial for the preservation of genomic stability that act as a barrier against tumorigenesis and tumor progression. Mutations and/or deletions of ATM and/or CHK2 are frequently found in tumors and predispose to cancer development. In contrast, the ATR-CHK1 pathway is often upregulated in neoplasms and is believed to promote tumor growth, although some evidence indicates that ATR and CHK1 may also behave as haploinsufficient oncosuppressors, at least in a specific genetic background. Inactivation of the ATM-CHK2 and ATR-CHK1 pathways efficiently sensitizes malignant cells to radiotherapy and chemotherapy. Moreover, ATR and CHK1 inhibitors selectively kill tumor cells that present high levels of replication stress, have a deficiency in p53 (or other DDR players), or upregulate the ATR-CHK1 module. Despite promising preclinical results, the clinical activity of ATM, ATR, CHK1, and CHK2 inhibitors, alone or in combination with other therapeutics, has not yet been fully demonstrated. In this Trial Watch, we give an overview of the roles of the ATM-CHK2 and ATR-CHK1 pathways in cancer initiation and progression, and summarize the results of clinical studies aimed at assessing the safety and therapeutic profile of regimens based on inhibitors of ATR and CHK1, the only 2 classes of compounds that have so far entered clinics.
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Affiliation(s)
| | - Florine Obrist
- Université Paris-Sud/Paris XI; Le Kremlin-Bicêtre, France
- INSERM, UMRS1138; Paris, France
- Equipe 11 labelisée par la Ligue Nationale contre le Cancer; Centre de Recherche des Cordeliers; Paris, France
- Gustave Roussy Cancer Campus; Villejuif, France
| | | | - Ilio Vitale
- Regina Elena National Cancer Institute; Rome, Italy
- Department of Biology, University of Rome “TorVergata”; Rome, Italy
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17
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Biss M, Xiao W. Selective tumor killing based on specific DNA-damage response deficiencies. Cancer Biol Ther 2014; 13:239-46. [DOI: 10.4161/cbt.18921] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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18
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Fokas E, Prevo R, Hammond EM, Brunner TB, McKenna WG, Muschel RJ. Targeting ATR in DNA damage response and cancer therapeutics. Cancer Treat Rev 2014; 40:109-17. [PMID: 23583268 DOI: 10.1016/j.ctrv.2013.03.002] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 03/06/2013] [Accepted: 03/06/2013] [Indexed: 12/12/2022]
Abstract
The ataxia telangiectasia and Rad3-related (ATR) plays an important role in maintaining genome integrity during DNA replication through the phosphorylation and activation of Chk1 and regulation of the DNA damage response. Preclinical studies have shown that disruption of ATR pathway can exacerbate the levels of replication stress in oncogene-driven murine tumors to promote cell killing. Additionally, inhibition of ATR can sensitise tumor cells to radiation or chemotherapy. Accumulating evidence suggests that targeting ATR can selectively sensitize cancer cells but not normal cells to DNA damage. Furthermore, in hypoxic conditions, ATR blockade results in overloading replication stress and DNA damage response causing cell death. Despite the attractiveness of ATR inhibition in the treatment of cancer, specific ATR inhibitors have remained elusive. In the last two years however, selective ATR inhibitors suitable for in vitro and - most recently - in vivo studies have been identified. In this article, we will review the literature on ATR function, its role in DDR and the potential of ATR inhibition to enhance the efficacy of radiation and chemotherapy.
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Affiliation(s)
- Emmanouil Fokas
- Gray Institute for Radiation Oncology and Biology, Department of Oncology, Oxford University, Oxford, United Kingdom; Department of Radiation Therapy and Oncology, Johann Wolfgang Goethe University, Frankfurt, Germany.
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19
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Dominguez-Valentin M, Therkildsen C, Veerla S, Jönsson M, Bernstein I, Borg A, Nilbert M. Distinct gene expression signatures in lynch syndrome and familial colorectal cancer type x. PLoS One 2013; 8:e71755. [PMID: 23951239 PMCID: PMC3741139 DOI: 10.1371/journal.pone.0071755] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 07/02/2013] [Indexed: 02/01/2023] Open
Abstract
Introduction Heredity is estimated to cause at least 20% of colorectal cancer. The hereditary nonpolyposis colorectal cancer subset is divided into Lynch syndrome and familial colorectal cancer type X (FCCTX) based on presence of mismatch repair (MMR) gene defects. Purpose We addressed the gene expression signatures in colorectal cancer linked to Lynch syndrome and FCCTX with the aim to identify candidate genes and to map signaling pathways relevant in hereditary colorectal carcinogenesis. Experimental design The 18 k whole-genome c-DNA-mediated annealing, selection, extension, and ligation (WG-DASL) assay was applied to 123 colorectal cancers, including 39 Lynch syndrome tumors and 37 FCCTX tumors. Target genes were technically validated using real-time quantitative RT-PCR (qRT-PCR) and the expression signature was validated in independent datasets. Results Colorectal cancers linked to Lynch syndrome and FCCTX showed distinct gene expression profiles, which by significance analysis of microarrays (SAM) differed by 2188 genes. Functional pathways involved were related to G-protein coupled receptor signaling, oxidative phosphorylation, and cell cycle function and mitosis. qRT-PCR verified altered expression of the selected genes NDUFA9, AXIN2, MYC, DNA2 and H2AFZ. Application of the 2188-gene signature to independent datasets showed strong correlation to MMR status. Conclusion Distinct genetic profiles and deregulation of different canonical pathways apply to Lynch syndrome and FCCTX and key targets herein may be relevant to pursue for refined diagnostic and therapeutic strategies in hereditary colorectal cancer.
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20
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Huehls AM, Wagner JM, Huntoon CJ, Karnitz LM. Identification of DNA repair pathways that affect the survival of ovarian cancer cells treated with a poly(ADP-ribose) polymerase inhibitor in a novel drug combination. Mol Pharmacol 2012; 82:767-76. [PMID: 22833573 PMCID: PMC3463227 DOI: 10.1124/mol.112.080614] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 07/24/2012] [Indexed: 12/17/2022] Open
Abstract
Floxuridine (5-fluorodeoxyuridine, FdUrd), a U.S. Food and Drug Administration-approved drug and metabolite of 5-fluorouracil, causes DNA damage that is repaired by base excision repair (BER). Thus, poly(ADP-ribose) polymerase (PARP) inhibitors, which disrupt BER, markedly sensitize ovarian cancer cells to FdUrd, suggesting that this combination may have activity in this disease. It remains unclear, however, which DNA repair and checkpoint signaling pathways affect killing by these agents individually and in combination. Here we show that depleting ATR, BRCA1, BRCA2, or RAD51 sensitized to ABT-888 (veliparib) alone, FdUrd alone, and FdUrd + ABT-888 (F+A), suggesting that homologous recombination (HR) repair protects cells exposed to these agents. In contrast, disabling the mismatch, nucleotide excision, Fanconi anemia, nonhomologous end joining, or translesion synthesis repair pathways did not sensitize to these agents alone (including ABT-888) or in combination. Further studies demonstrated that in BRCA1-depleted cells, F+A was more effective than other chemotherapy+ABT-888 combinations. Taken together, these studies 1) identify DNA repair and checkpoint pathways that are important in ovarian cancer cells treated with FdUrd, ABT-888, and F+A, 2) show that disabling HR at the level of ATR, BRCA1, BRCA2, or RAD51, but not Chk1, ATM, PTEN, or FANCD2, sensitizes cells to ABT-888, and 3) demonstrate that even though ABT-888 sensitizes ovarian tumor cells with functional HR to FdUrd, the effects of this drug combination are more profound in tumors with HR defects, even compared with other chemotherapy + ABT-888 combinations, including cisplatin + ABT-888.
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Affiliation(s)
- Amelia M Huehls
- Division of Oncology Research, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, College of Medicine, Rochester, Minnesota, USA
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de la Cruz-Morcillo MA, Valero MLL, Callejas-Valera JL, Arias-González L, Melgar-Rojas P, Galán-Moya EM, García-Gil E, García-Cano J, Sánchez-Prieto R. P38MAPK is a major determinant of the balance between apoptosis and autophagy triggered by 5-fluorouracil: implication in resistance. Oncogene 2012; 31:1073-85. [PMID: 21841826 DOI: 10.1038/onc.2011.321] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Revised: 06/22/2011] [Accepted: 06/23/2011] [Indexed: 12/30/2022]
Abstract
5-Fluorouracil (5-FU), together with other drugs such as oxaliplatin, is one of the most important pharmacological agents in the treatment of colorectal cancer. Although mitogen-activated protein kinases (MAPKs) have been extensively connected with resistance to platinum compounds, no role has been established in 5-FU resistance. Here we demonstrate that p38MAPK activation is a key determinant in the cellular response to 5-FU. Thus, inhibition of p38MAPKα by SB203580 compound or by short-hairpin RNA interference-specific knockdown correlates with a decrease in the 5-FU-associated apoptosis and chemical resistance in both HaCaT and HCT116 cells. Activation of p38MAPK by 5-FU was dependent on canonical MAP2K, MAPK kinase (MKK)-3 and MKK6. In addition, ataxia telangiectasia mutated (ATM) and ataxia telangiectasia and Rad3 related (ATR) showed a redundancy of function for the final activation of p38MAPK. Resistance associated with p38MAPK inhibition correlates with an autophagic response that was mediated by a decrease in p53-driven apoptosis, without effect onto p53-dependent autophagy. Moreover, the results with colorectal cancer-derived cell lines with different p53 status and patterns of resistance to 5-FU suggest that de novo and acquired resistance was controlled by similar mechanisms. In summary, our data demonstrate a critical role for the p38MAPK signaling pathway in the cellular response to 5-FU by controlling the balance between apoptosis and autophagy.
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Affiliation(s)
- M A de la Cruz-Morcillo
- Laboratorio de Oncología Molecular, Centro Regional de Investigaciones Biomédicas, CRIB/PCYTA, Universidad de Castilla-La Mancha, UCLM, Albacete, Spain
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22
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Checkpoint signaling, base excision repair, and PARP promote survival of colon cancer cells treated with 5-fluorodeoxyuridine but not 5-fluorouracil. PLoS One 2011; 6:e28862. [PMID: 22194930 PMCID: PMC3240632 DOI: 10.1371/journal.pone.0028862] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 11/16/2011] [Indexed: 12/19/2022] Open
Abstract
The fluoropyrimidines 5-fluorouracil (5-FU) and FdUrd (5-fluorodeoxyuridine; floxuridine) are the backbone of chemotherapy regimens for colon cancer and other tumors. Despite their widespread use, it remains unclear how these agents kill tumor cells. Here, we have analyzed the checkpoint and DNA repair pathways that affect colon tumor responses to 5-FU and FdUrd. These studies demonstrate that both FdUrd and 5-FU activate the ATR and ATM checkpoint signaling pathways, indicating that they cause genotoxic damage. Notably, however, depletion of ATM or ATR does not sensitize colon cancer cells to 5-FU, whereas these checkpoint pathways promote the survival of cells treated with FdUrd, suggesting that FdUrd exerts cytotoxicity by disrupting DNA replication and/or inducing DNA damage, whereas 5-FU does not. We also found that disabling the base excision (BER) repair pathway by depleting XRCC1 or APE1 sensitized colon cancer cells to FdUrd but not 5-FU. Consistent with a role for the BER pathway, we show that small molecule poly(ADP-ribose) polymerase 1/2 (PARP) inhibitors, AZD2281 and ABT-888, remarkably sensitized both mismatch repair (MMR)-proficient and -deficient colon cancer cell lines to FdUrd but not to 5-FU. Taken together, these studies demonstrate that the roles of genotoxin-induced checkpoint signaling and DNA repair differ significantly for these agents and also suggest a novel approach to colon cancer therapy in which FdUrd is combined with a small molecule PARP inhibitor.
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Nam EA, Zhao R, Cortez D. Analysis of mutations that dissociate G(2) and essential S phase functions of human ataxia telangiectasia-mutated and Rad3-related (ATR) protein kinase. J Biol Chem 2011; 286:37320-7. [PMID: 21908846 DOI: 10.1074/jbc.m111.276113] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
ATR (ataxia telangiectasia-mutated and Rad3-related) contains 16 conserved candidate autophosphorylation sites that match its preferred S/TQ consensus. To determine whether any is functionally important, we mutated the 16 candidate residues to alanine in a single cDNA to create a 16A-ATR mutant. The 16A-ATR mutant maintains kinase and G(2) checkpoint activities. However, it fails to rescue the essential function of ATR in maintaining cell viability and fails to promote replication recovery from a transient exposure to replication stress. Further analysis identified T1566A/T1578A/T1589A (3A-ATR) as critical mutations causing this separation of function activity. Secondary structure predictions indicate that these residues occur in a region between ATR HEAT repeats 31R and 32R that aligns with regions of ATM and DNA-PK containing regulatory autophosphorylation sites. Although this region is important for ATR function, the 3A-ATR residues do not appear to be sites of autophosphorylation. Nevertheless, our analysis identifies an important regulatory region of ATR that is shared among the PI3K-related protein kinase family. Furthermore, our data indicate that the essential function of ATR for cell viability is linked to its function in promoting proper replication in the context of replication stress and is independent of G(2) checkpoint activity.
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Affiliation(s)
- Edward A Nam
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
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24
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Huehls AM, Wagner JM, Huntoon CJ, Geng L, Erlichman C, Patel AG, Kaufmann SH, Karnitz LM. Poly(ADP-Ribose) polymerase inhibition synergizes with 5-fluorodeoxyuridine but not 5-fluorouracil in ovarian cancer cells. Cancer Res 2011; 71:4944-54. [PMID: 21613406 PMCID: PMC3138894 DOI: 10.1158/0008-5472.can-11-0814] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
5-Fluorouracil (5-FU) and 5-fluorodeoxyuridine (FdUrd, floxuridine) have activity in multiple tumors, and both agents undergo intracellular processing to active metabolites that disrupt RNA and DNA metabolism. These agents cause imbalances in deoxynucleotide triphosphate levels and the accumulation of uracil and 5-FU in the genome, events that activate the ATR- and ATM-dependent checkpoint signaling pathways and the base excision repair (BER) pathway. Here, we assessed which DNA damage response and repair processes influence 5-FU and FdUrd toxicity in ovarian cancer cells. These studies revealed that disabling the ATM, ATR, or BER pathways using small inhibitory RNAs did not affect 5-FU cytotoxicity. In stark contrast, ATR and a functional BER pathway protected FdUrd-treated cells. Consistent with a role for the BER pathway, the poly(ADP-ribose) polymerase (PARP) inhibitors ABT-888 (veliparib) and AZD2281 (olaparib) markedly synergized with FdUrd but not with 5-FU in ovarian cancer cell lines. Furthermore, ABT-888 synergized with FdUrd far more effectively than other agents commonly used to treat ovarian cancer. These findings underscore differences in the cytotoxic mechanisms of 5-FU and FdUrd and suggest that combining FdUrd and PARP inhibitors may be an innovative therapeutic strategy for ovarian tumors.
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Affiliation(s)
- Amelia M. Huehls
- Division of Oncology Research, Mayo Clinic, College of Medicine, Rochester, Minnesota
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, College of Medicine, Rochester, Minnesota
| | - Jill M. Wagner
- Division of Oncology Research, Mayo Clinic, College of Medicine, Rochester, Minnesota
| | - Catherine J. Huntoon
- Division of Oncology Research, Mayo Clinic, College of Medicine, Rochester, Minnesota
| | - Liyi Geng
- Division of Oncology Research, Mayo Clinic, College of Medicine, Rochester, Minnesota
| | - Charles Erlichman
- Division of Medical Oncology, Mayo Clinic, College of Medicine, Rochester, Minnesota
| | - Anand G. Patel
- Division of Oncology Research, Mayo Clinic, College of Medicine, Rochester, Minnesota
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, College of Medicine, Rochester, Minnesota
| | - Scott H. Kaufmann
- Division of Oncology Research, Mayo Clinic, College of Medicine, Rochester, Minnesota
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, College of Medicine, Rochester, Minnesota
| | - Larry M. Karnitz
- Division of Oncology Research, Mayo Clinic, College of Medicine, Rochester, Minnesota
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, College of Medicine, Rochester, Minnesota
- Department of Radiation Oncology, Mayo Clinic, College of Medicine, Rochester, Minnesota
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25
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Kim AJ, Kim HJ, Jee HJ, Song N, Kim M, Bae YS, Chung JH, Yun J. Glucose deprivation is associated with Chk1 degradation through the ubiquitin-proteasome pathway and effective checkpoint response to replication blocks. BIOCHIMICA ET BIOPHYSICA ACTA 2011; 1813:1230-8. [PMID: 21440578 PMCID: PMC3779427 DOI: 10.1016/j.bbamcr.2011.03.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 03/16/2011] [Accepted: 03/17/2011] [Indexed: 11/19/2022]
Abstract
Chk1 plays a key role in the DNA replication checkpoint and in preserving genomic integrity. Previous studies have shown that reduced Chk1 function leads to defects in the checkpoint response and is closely associated with tumorigenesis. Here, we report that glucose deprivation caused the degradation of Chk1 protein without perturbing cell cycle progression. The induction of Chk1 degradation in response to glucose deprivation was observed in various cancer cell lines and in normal human fibroblasts. Therefore, it appears to be a universal phenomenon in mammalian cells. A specific proteasome inhibitor blocked glucose deprivation-induced Chk1 degradation. Ubiquitination of Chk1 was detected, indicating that the proteasome-ubiquitin pathway mediates Chk1 degradation upon glucose deprivation. Mechanistic studies have demonstrated that ATR-dependent phosphorylation of Chk1 at the Ser317 and Ser345 sites is not required, suggesting that the molecular mechanism for Chk1 degradation upon glucose deprivation is distinct from genotoxic stress-induced degradation. Under conditions of glucose deprivation, the cells manifested a defective checkpoint response to replication stress, camptothecin or hydroxyurea. The forced expression of Myc-Chk1 partially rescued the defective response to the replication block upon glucose deprivation. Taken together, our results indicate that glucose deprivation induces ubiquitin-mediated Chk1 degradation and defective checkpoint responses, implying its potential role in genomic instability and tumor development.
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Affiliation(s)
- Ae Jeong Kim
- Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714, South Korea
- Mitochondria Hub Regulation Center, College of Medicine, Dong-A University, Busan 602-714, South Korea
| | - Hyun-Ju Kim
- Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714, South Korea
- Mitochondria Hub Regulation Center, College of Medicine, Dong-A University, Busan 602-714, South Korea
| | - Hye Jin Jee
- Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714, South Korea
- Mitochondria Hub Regulation Center, College of Medicine, Dong-A University, Busan 602-714, South Korea
| | - Naree Song
- Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714, South Korea
- Mitochondria Hub Regulation Center, College of Medicine, Dong-A University, Busan 602-714, South Korea
| | - Minjee Kim
- Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714, South Korea
- Mitochondria Hub Regulation Center, College of Medicine, Dong-A University, Busan 602-714, South Korea
| | - Yoe-Sik Bae
- Department of Biological Science, Sungkyunkwan University, Suwon, 440-746, South Korea
| | - Jay H. Chung
- Laboratory of Biochemical Genetics, NHLBI, NIH, 10 Center Drive, Bethesda, Maryland 20892, USA
| | - Jeanho Yun
- Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714, South Korea
- Mitochondria Hub Regulation Center, College of Medicine, Dong-A University, Busan 602-714, South Korea
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26
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Persimmon leaf extract inhibits the ATM activity during DNA damage response induced by Doxorubicin in A549 lung adenocarcinoma cells. Biosci Biotechnol Biochem 2011; 75:650-5. [PMID: 21512242 DOI: 10.1271/bbb.100738] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Persimmon leaf (PL) has been commonly recognized for its wide variety of health benefits. A previous study has reported that persimmon leaf extract (PLE) contained flavonols with the 2″-galloly moiety (PLEg). Galloylated homologues generically show stronger activity in their biological function, so enhanced functions can be expected for PLEg. We investigated in this present study the effect of PLEg on the cellular DNA damage checkpoint signaling to sensitize cancer chemotherapy. Treatment with PLE and PLEg significantly increased the cytotoxicity of doxorubicin (DOX) in A549 adenocarcinoma cells. PLE and PLEg reduced the phosphorylation of checkpoint proteins such as structural maintenance of chromosomes 1 (SMC1), checkpoint kinase 1 (Chk1), and p53 in DOX-treated cells. Moreover, PLE decreased the phosphorylation of ATM (ataxia telangiectasia mutated) in a dose-dependent manner. PLE, and especially PLEg, abrogated the G2/M checkpoint during DOX-induced DNA damage. These results suggest that PLEg specifically inhibited ATM-dependent checkpoint activation by DOX, and that PLEg might be a useful sensitizer in cancer chemotherapy.
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27
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Guzi TJ, Paruch K, Dwyer MP, Labroli M, Shanahan F, Davis N, Taricani L, Wiswell D, Seghezzi W, Penaflor E, Bhagwat B, Wang W, Gu D, Hsieh Y, Lee S, Liu M, Parry D. Targeting the replication checkpoint using SCH 900776, a potent and functionally selective CHK1 inhibitor identified via high content screening. Mol Cancer Ther 2011; 10:591-602. [PMID: 21321066 DOI: 10.1158/1535-7163.mct-10-0928] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Checkpoint kinase 1 (CHK1) is an essential serine/threonine kinase that responds to DNA damage and stalled DNA replication. CHK1 is essential for maintenance of replication fork viability during exposure to DNA antimetabolites. In human tumor cell lines, ablation of CHK1 function during antimetabolite exposure led to accumulation of double-strand DNA breaks and cell death. Here, we extend these observations and confirm ablation of CHK2 does not contribute to these phenotypes and may diminish them. Furthermore, concomitant suppression of cyclin-dependent kinase (CDK) activity is sufficient to completely antagonize the desired CHK1 ablation phenotypes. These mechanism-based observations prompted the development of a high-content, cell-based screen for γ-H2AX induction, a surrogate marker for double-strand DNA breaks. This mechanism-based functional approach was used to optimize small molecule inhibitors of CHK1. Specifically, the assay was used to mechanistically define the optimal in-cell profile with compounds exhibiting varying degrees of CHK1, CHK2, and CDK selectivity. Using this approach, SCH 900776 was identified as a highly potent and functionally optimal CHK1 inhibitor with minimal intrinsic antagonistic properties. SCH 900776 exposure phenocopies short interfering RNA-mediated CHK1 ablation and interacts synergistically with DNA antimetabolite agents in vitro and in vivo to selectively induce dsDNA breaks and cell death in tumor cell backgrounds.
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28
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Wagner JM, Kaufmann SH. Prospects for the Use of ATR Inhibitors to Treat Cancer. Pharmaceuticals (Basel) 2010; 3:1311-1334. [PMID: 27713304 PMCID: PMC4033983 DOI: 10.3390/ph3051311] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 04/12/2010] [Accepted: 04/19/2010] [Indexed: 01/08/2023] Open
Abstract
ATR is an apical kinase in one of the DNA-damage induced checkpoint pathways. Despite the development of inhibitors of kinases structurally related to ATR, as well as inhibitors of the ATR substrate Chk1, no ATR inhibitors have yet been developed. Here we review the effects of ATR downregulation in cancer cells and discuss the potential for development of ATR inhibitors for clinical use.
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Affiliation(s)
- Jill M Wagner
- Division of Oncology Research, College of Medicine, Mayo Clinic, 200 First St., S.W., Rochester, MN 55905, USA.
| | - Scott H Kaufmann
- Division of Oncology Research, College of Medicine, Mayo Clinic, 200 First St., S.W., Rochester, MN 55905, USA.
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