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Ricciuti B, Elkrief A, Alessi J, Wang X, Li Y, Gupta H, Muldoon DM, Bertram AA, Pecci F, Lamberti G, Federico AD, Barrichello A, Vaz VR, Gandhi M, Lee E, Shapiro GI, Park H, Nishino M, Lindsay J, Felt KD, Sharma B, Cherniack AD, Rodig S, Gomez DR, Shaverdian N, Rakaee M, Bandlamudi C, Ladanyi M, Janne PA, Schoenfeld AJ, Sholl LM, Awad MM, Cheng ML. Clinicopathologic, Genomic, and Immunophenotypic Landscape of ATM Mutations in Non-Small Cell Lung Cancer. Clin Cancer Res 2023; 29:2540-2550. [PMID: 37097610 PMCID: PMC11031845 DOI: 10.1158/1078-0432.ccr-22-3413] [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: 11/04/2022] [Revised: 03/09/2023] [Accepted: 04/20/2023] [Indexed: 04/26/2023]
Abstract
PURPOSE ATM is the most commonly mutated DNA damage and repair gene in non-small cell lung cancer (NSCLC); however, limited characterization has been pursued. EXPERIMENTAL DESIGN Clinicopathologic, genomic, and treatment data were collected for 5,172 patients with NSCLC tumors which underwent genomic profiling. ATM IHC was performed on 182 NSCLCs with ATM mutations. Multiplexed immunofluorescence was performed on a subset of 535 samples to examine tumor-infiltrating immune cell subsets. RESULTS A total of 562 deleterious ATM mutations were identified in 9.7% of NSCLC samples. ATM-mutant (ATMMUT) NSCLC was significantly associated with female sex (P = 0.02), ever smoking status (P < 0.001), non-squamous histology (P = 0.004), and higher tumor mutational burden (DFCI, P < 0.0001; MSK, P < 0.0001) compared with ATM-wild-type (ATMWT) cases. Among 3,687 NSCLCs with comprehensive genomic profiling, co-occurring KRAS, STK11, and ARID2 oncogenic mutations were significantly enriched among ATMMUT NSCLCs (Q < 0.05), while TP53 and EGFR mutations were enriched in ATMWT NSCLCs. Among 182 ATMMUT samples with ATM IHC, tumors with nonsense, insertions/deletions, or splice site mutations were significantly more likely to display ATM loss by IHC (71.4% vs. 28.6%; P < 0.0001) compared with tumors with only predicted pathogenic missense mutations. Clinical outcomes to PD-(L)1 monotherapy (N = 1,522) and chemo-immunotherapy (N = 951) were similar between ATMMUT and ATMWT NSCLCs. Patients with concurrent ATM/TP53 mutations had significantly improved response rate and progression-free survival with PD-(L)1 monotherapy. CONCLUSIONS Deleterious ATM mutations defined a subset of NSCLC with unique clinicopathologic, genomic, and immunophenotypic features. Our data may serve as resource to guide interpretation of specific ATM mutations in NSCLC.
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Affiliation(s)
- Biagio Ricciuti
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Arielle Elkrief
- Thoracic Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Joao Alessi
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Xinan Wang
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Yvonne Li
- Department of Analytics and Informatics, Dana-Farber Cancer Institute, Boston, Massachusetts; Cancer Program, Broad Institute of Harvard and Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts
| | - Hersh Gupta
- Department of Analytics and Informatics, Dana-Farber Cancer Institute, Boston, Massachusetts; Cancer Program, Broad Institute of Harvard and Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts
| | - Daniel M. Muldoon
- Thoracic Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Arrien A. Bertram
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Federica Pecci
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Giuseppe Lamberti
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Alessandro Di Federico
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Adriana Barrichello
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Victor R. Vaz
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Malini Gandhi
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Elinton Lee
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Geoffrey I. Shapiro
- Center for DNA Damage and Repair (CDDR), Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Hyesun Park
- Department of Radiology, Brigham and Women’s Hospital, Boston, Massachusetts
| | - Mizuki Nishino
- Department of Radiology, Brigham and Women’s Hospital, Boston, Massachusetts
| | - James Lindsay
- ImmunoProfile, Brigham & Women’s Hospital and Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Kristen D. Felt
- ImmunoProfile, Brigham & Women’s Hospital and Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Bijaya Sharma
- ImmunoProfile, Brigham & Women’s Hospital and Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Andrew D. Cherniack
- Department of Analytics and Informatics, Dana-Farber Cancer Institute, Boston, Massachusetts; Cancer Program, Broad Institute of Harvard and Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts
| | - Scott Rodig
- Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts
| | - Daniel R. Gomez
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Narek Shaverdian
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Mehrdad Rakaee
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Chaitanya Bandlamudi
- Thoracic Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Marc Ladanyi
- Thoracic Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Pasi A. Janne
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Adam J. Schoenfeld
- Thoracic Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Lynette M. Sholl
- Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts
| | - Mark M. Awad
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Michael L. Cheng
- Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
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Gupta N, Huang TT, Nair JR, An D, Zurcher G, Lampert EJ, McCoy A, Cimino-Mathews A, Swisher EM, Radke MR, Lockwood CM, Reichel JB, Chiang CY, Wilson KM, Chih-Chien Cheng K, Nousome D, Lee JM. BLM overexpression as a predictive biomarker for CHK1 inhibitor response in PARP inhibitor-resistant BRCA-mutant ovarian cancer. Sci Transl Med 2023; 15:eadd7872. [PMID: 37343085 PMCID: PMC10758289 DOI: 10.1126/scitranslmed.add7872] [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: 07/04/2022] [Accepted: 06/02/2023] [Indexed: 06/23/2023]
Abstract
Poly(ADP-ribose) polymerase inhibitors (PARPis) have changed the treatment paradigm in breast cancer gene (BRCA)-mutant high-grade serous ovarian carcinoma (HGSC). However, most patients eventually develop resistance to PARPis, highlighting an unmet need for improved therapeutic strategies. Using high-throughput drug screens, we identified ataxia telangiectasia and rad3-related protein/checkpoint kinase 1 (CHK1) pathway inhibitors as cytotoxic and further validated the activity of the CHK1 inhibitor (CHK1i) prexasertib in PARPi-sensitive and -resistant BRCA-mutant HGSC cells and xenograft mouse models. CHK1i monotherapy induced DNA damage, apoptosis, and tumor size reduction. We then conducted a phase 2 study (NCT02203513) of prexasertib in patients with BRCA-mutant HGSC. The treatment was well tolerated but yielded an objective response rate of 6% (1 of 17; one partial response) in patients with previous PARPi treatment. Exploratory biomarker analyses revealed that replication stress and fork stabilization were associated with clinical benefit to CHK1i. In particular, overexpression of Bloom syndrome RecQ helicase (BLM) and cyclin E1 (CCNE1) overexpression or copy number gain/amplification were seen in patients who derived durable benefit from CHK1i. BRCA reversion mutation in previously PARPi-treated BRCA-mutant patients was not associated with resistance to CHK1i. Our findings suggest that replication fork-related genes should be further evaluated as biomarkers for CHK1i sensitivity in patients with BRCA-mutant HGSC.
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Affiliation(s)
- Nitasha Gupta
- Women’s Malignancies Branch, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Tzu-Ting Huang
- Women’s Malignancies Branch, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Jayakumar R. Nair
- Women’s Malignancies Branch, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Daniel An
- Women’s Malignancies Branch, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Grant Zurcher
- Women’s Malignancies Branch, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Erika J. Lampert
- Women’s Malignancies Branch, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
- Department of Obstetrics and Gynecology, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Ann McCoy
- Women’s Malignancies Branch, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Ashley Cimino-Mathews
- Departments of Pathology and Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Elizabeth M. Swisher
- Brotman Baty Institute of Precision Medicine, University of Washington, Seattle, WA 98195, USA
| | - Marc R. Radke
- Brotman Baty Institute of Precision Medicine, University of Washington, Seattle, WA 98195, USA
| | - Christina M. Lockwood
- Brotman Baty Institute of Precision Medicine, University of Washington, Seattle, WA 98195, USA
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA
| | - Jonathan B. Reichel
- Brotman Baty Institute of Precision Medicine, University of Washington, Seattle, WA 98195, USA
| | - Chih-Yuan Chiang
- National Center for Advancing Translational Sciences, National Institutes of Health (NIH), Rockville, MD 20892, USA
| | - Kelli M. Wilson
- National Center for Advancing Translational Sciences, National Institutes of Health (NIH), Rockville, MD 20892, USA
| | - Ken Chih-Chien Cheng
- National Center for Advancing Translational Sciences, National Institutes of Health (NIH), Rockville, MD 20892, USA
| | - Darryl Nousome
- Center for Cancer Research Collaborative Bioinformatics Resource, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Jung-Min Lee
- Women’s Malignancies Branch, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
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Chowdhury SR, Koley T, Singh M, Samath EA, Kaur P. Association of Hsp90 with p53 and Fizzy related homolog (Fzr) synchronizing Anaphase Promoting Complex (APC/C): An unexplored ally towards oncogenic pathway. Biochim Biophys Acta Rev Cancer 2023; 1878:188883. [PMID: 36972769 DOI: 10.1016/j.bbcan.2023.188883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 03/29/2023]
Abstract
The intricate molecular interactions leading to the oncogenic pathway are the consequence of cell cycle modification controlled by a bunch of cell cycle regulatory proteins. The tumor suppressor and cell cycle regulatory proteins work in coordination to maintain a healthy cellular environment. The integrity of this cellular protein pool is perpetuated by heat shock proteins/chaperones, which assist in proper protein folding during normal and cellular stress conditions. Among these versatile groups of chaperone proteins, Hsp90 is one of the significant ATP-dependent chaperones that aid in stabilizing many tumor suppressors and cell cycle regulator protein targets. Recently, studies have revealed that in cancerous cell lines, Hsp90 stabilizes mutant p53, 'the guardian of the genome.' Hsp90 also has a significant impact on Fzr, an essential regulator of the cell cycle having an important role in the developmental process of various organisms, including Drosophila, yeast, Caenorhabditis elegans, and plants. During cell cycle progression, p53 and Fzr coordinately regulate the Anaphase Promoting Complex (APC/C) from metaphase to anaphase transition up to cell cycle exit. APC/C mediates proper centrosome function in the dividing cell. The centrosome acts as the microtubule organizing center for the correct segregation of the sister chromatids to ensure perfect cell division. This review examines the structure of Hsp90 and its co-chaperones, which work in synergy to stabilize proteins such as p53 and Fizzy-related homolog (Fzr) to synchronize the Anaphase Promoting Complex (APC/C). Dysfunction of this process activates the oncogenic pathway leading to the development of cancer. Additionally, an overview of current drugs targeting Hsp90 at various phases of clinical trials has been included.
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Affiliation(s)
- Sanghati Roy Chowdhury
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Tirthankar Koley
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Mandeep Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | | | - Punit Kaur
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India.
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4
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Han S, Lim KS, Blackburn BJ, Yun J, Putnam CW, Bull DA, Won YW. The Potential of Topoisomerase Inhibitor-Based Antibody–Drug Conjugates. Pharmaceutics 2022; 14:pharmaceutics14081707. [PMID: 36015333 PMCID: PMC9413092 DOI: 10.3390/pharmaceutics14081707] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/08/2022] [Accepted: 08/11/2022] [Indexed: 12/17/2022] Open
Abstract
DNA topoisomerases are essential enzymes that stabilize DNA supercoiling and resolve entanglements. Topoisomerase inhibitors have been widely used as anti-cancer drugs for the past 20 years. Due to their selectivity as topoisomerase I (TOP1) inhibitors that trap TOP1 cleavage complexes, camptothecin and its derivatives are promising anti-cancer drugs. To increase accumulation of TOP1 inhibitors in cancer cells through the targeting of tumors, TOP1 inhibitor antibody–drug conjugates (TOP1-ADC) have been developed and marketed. Some TOP1-ADCs have shown enhanced therapeutic efficacy compared to prototypical anti-cancer ADCs, such as T-DM1. Here, we review various types of camptothecin-based TOP1 inhibitors and recent developments in TOP1-ADCs. We then propose key points for the design and construction of TOP1-ADCs. Finally, we discuss promising combinatorial strategies, including newly developed approaches to maximizing the therapeutic potential of TOP1-ADCs.
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Affiliation(s)
- Seungmin Han
- Division of Cardiothoracic Surgery, Department of Surgery, University of Arizona College of Medicine—Tucson, Tucson, AZ 85724, USA
| | - Kwang Suk Lim
- Department of Biotechnology and Bioengineering, College of Art, Culture and Engineering, Kangwon National University, Chuncheon 24341, Korea
- Department of Smart Health Science and Technology, College of Art, Culture and Engineering, Kangwon National University, Chuncheon 24341, Korea
| | - Brody J. Blackburn
- Department of Medical Pharmacology, University of Arizona College of Medicine—Tucson, Tucson, AZ 85724, USA
| | - Jina Yun
- Division of Hematology-Oncology, Department of Medicine, Soonchunhyang University Bucheon Hospital, Bucheon 14584, Korea
| | - Charles W. Putnam
- Division of Cardiothoracic Surgery, Department of Surgery, University of Arizona College of Medicine—Tucson, Tucson, AZ 85724, USA
| | - David A. Bull
- Division of Cardiothoracic Surgery, Department of Surgery, University of Arizona College of Medicine—Tucson, Tucson, AZ 85724, USA
| | - Young-Wook Won
- Division of Cardiothoracic Surgery, Department of Surgery, University of Arizona College of Medicine—Tucson, Tucson, AZ 85724, USA
- Correspondence:
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5
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Kelly RL, Huehls AM, Venkatachalam A, Huntoon CJ, Machida YJ, Karnitz LM. Intra-S phase checkpoint kinase Chk1 dissociates replication proteins Treslin and TopBP1 through multiple mechanisms during replication stress. J Biol Chem 2022; 298:101777. [PMID: 35231445 PMCID: PMC8965152 DOI: 10.1016/j.jbc.2022.101777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 02/17/2022] [Accepted: 02/19/2022] [Indexed: 11/17/2022] Open
Abstract
Replication stress impedes DNA polymerase progression causing activation of the ataxia telangiectasia and Rad3-related signaling pathway, which promotes the intra-S phase checkpoint activity through phosphorylation of checkpoint kinase 1 (Chk1). Chk1 suppresses replication origin firing, in part, by disrupting the interaction between the preinitiation complex components Treslin and TopBP1, an interaction that is mediated by TopBP1 BRCT domain-binding to two cyclin-dependent kinase (CDK) phosphorylation sites, T968 and S1000, in Treslin. Two nonexclusive models for how Chk1 regulates the Treslin–TopBP1 interaction have been proposed in the literature: in one model, these proteins dissociate due to a Chk1-induced decrease in CDK activity that reduces phosphorylation of the Treslin sites that bind TopBP1 and in the second model, Chk1 directly phosphorylates Treslin, resulting in dissociation of TopBP1. However, these models have not been formally examined. We show here that Treslin T968 phosphorylation was decreased in a Chk1-dependent manner, while Treslin S1000 phosphorylation was unchanged, demonstrating that T968 and S1000 are differentially regulated. However, CDK2-mediated phosphorylation alone did not fully account for Chk1 regulation of the Treslin–TopBP1 interaction. We also identified additional Chk1 phosphorylation sites on Treslin that contributed to disruption of the Treslin–TopBP1 interaction, including S1114. Finally, we showed that both of the proposed mechanisms regulate origin firing in cancer cell line models undergoing replication stress, with the relative roles of each mechanism varying among cell lines. This study demonstrates that Chk1 regulates Treslin through multiple mechanisms to promote efficient dissociation of Treslin and TopBP1 and furthers our understanding of Treslin regulation during the intra-S phase checkpoint.
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Affiliation(s)
- Rebecca L Kelly
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA
| | - Amelia M Huehls
- Division of Oncology Research, Mayo Clinic, Rochester, Minnesota, USA
| | - Annapoorna Venkatachalam
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Yuichi J Machida
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA; Division of Oncology Research, Mayo Clinic, Rochester, Minnesota, USA
| | - Larry M Karnitz
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA; Division of Oncology Research, Mayo Clinic, Rochester, Minnesota, USA.
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Hinds JW, Ditano JP, Eastman A. Inhibition of Protein Synthesis Induced by CHK1 Inhibitors Discriminates Sensitive from Resistant Cancer Cells. ACS Pharmacol Transl Sci 2021; 4:1449-1461. [PMID: 34423276 DOI: 10.1021/acsptsci.1c00150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Indexed: 11/29/2022]
Abstract
The DNA-damage-activated checkpoint protein CHK1 is required to prevent replication or mitosis in the presence of unrepaired DNA damage. Inhibitors of CHK1 (CHK1i) circumvent this checkpoint and enhance cell killing by DNA-damaging drugs. CHK1i also elicit single-agent cytotoxicity in a small subset of cell lines. Resolving the mechanisms underlying the single-agent activity may permit patient stratification and targeted therapy against sensitive tumors. Our recent comparison of three CHK1i demonstrated that they all inhibited protein synthesis only in sensitive cells. LY2606368, the most selective of these CHK1i, was used in the current study. Comparison across a panel of cell lines demonstrated that sensitive cells died upon incubation with LY2606368, whereas resistant cells underwent growth inhibition and/or cytostasis but failed to die. Sensitive cells exhibited inhibition of protein synthesis, elevated DNA damage, impaired DNA repair, and subsequently death. The consequence of CHK1 inhibition involved activation of cyclin A/CDK2 and MUS81, resulting in DNA damage. This damage led to activation of AMPK, dephosphorylation of 4E-BP1, and inhibition of protein synthesis. Inhibition of MUS81 prevented activation of AMPK, while inhibition of AMPK enhanced DNA repair and cell survival. The activation of AMPK may involve a combination of LKB1 and CaMKKβ. This study raises questions concerning the potential importance of the inhibition of protein synthesis in response to other drugs, alone or in combination with CHK1i. It also highlights the importance of clearly discriminating among growth inhibition, cytostasis, and cell death, as only the latter is likely to result in tumor regression.
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Affiliation(s)
- John W Hinds
- Department of Molecular and Systems Biology and Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756, United States
| | - Jennifer P Ditano
- Department of Molecular and Systems Biology and Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756, United States
| | - Alan Eastman
- Department of Molecular and Systems Biology and Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire 03756, United States
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