1
|
Abbouche L, Bythell-Douglas R, Deans AJ. FANCM branchpoint translocase: Master of traverse, reverse and adverse DNA repair. DNA Repair (Amst) 2024; 140:103701. [PMID: 38878565 DOI: 10.1016/j.dnarep.2024.103701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 05/15/2024] [Accepted: 05/30/2024] [Indexed: 07/13/2024]
Abstract
FANCM is a multifunctional DNA repair enzyme that acts as a sensor and coordinator of replication stress responses, especially interstrand crosslink (ICL) repair mediated by the Fanconi anaemia (FA) pathway. Its specialised ability to bind and remodel branched DNA structures enables diverse genome maintenance activities. Through ATP-powered "branchpoint translocation", FANCM can promote fork reversal, facilitate replication traverse of ICLs, resolve deleterious R-loop structures, and restrain recombination. These remodelling functions also support a role as sensor of perturbed replication, eliciting checkpoint signalling and recruitment of downstream repair factors like the Fanconi anaemia FANCI:FANCD2 complex. Accordingly, FANCM deficiency causes chromosome fragility and cancer susceptibility. Other recent advances link FANCM to roles in gene editing efficiency and meiotic recombination, along with emerging synthetic lethal relationships, and targeting opportunities in ALT-positive cancers. Here we review key properties of FANCM's biochemical activities, with a particular focus on branchpoint translocation as a distinguishing characteristic.
Collapse
Affiliation(s)
- Lara Abbouche
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia; Department of Medicine (St Vincent's), University of Melbourne, Fitzroy, VIC, Australia
| | - Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia; Department of Medicine (St Vincent's), University of Melbourne, Fitzroy, VIC, Australia.
| |
Collapse
|
2
|
Monnat RJ. James German and the Quest to Understand Human RECQ Helicase Deficiencies. Cells 2024; 13:1077. [PMID: 38994931 PMCID: PMC11240319 DOI: 10.3390/cells13131077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 05/10/2024] [Accepted: 06/14/2024] [Indexed: 07/13/2024] Open
Abstract
James German's work to establish the natural history and cancer risk associated with Bloom syndrome (BS) has had a strong influence on the generation of scientists and clinicians working to understand other RECQ deficiencies and heritable cancer predisposition syndromes. I summarize work by us and others below, inspired by James German's precedents with BS, to understand and compare BS with the other heritable RECQ deficiency syndromes with a focus on Werner syndrome (WS). What we know, unanswered questions and new opportunities are discussed, as are potential ways to treat or modify WS-associated disease mechanisms and pathways.
Collapse
Affiliation(s)
- Raymond J Monnat
- Departments of Laboratory Medicine/Pathology and Genome Sciences, University of Washington, Seattle, WA 98195, USA
| |
Collapse
|
3
|
Koh GCC, Boushaki S, Zhao SJ, Pregnall AM, Sadiyah F, Badja C, Memari Y, Georgakopoulos-Soares I, Nik-Zainal S. The chemotherapeutic drug CX-5461 is a potent mutagen in cultured human cells. Nat Genet 2024; 56:23-26. [PMID: 38036782 PMCID: PMC10786719 DOI: 10.1038/s41588-023-01602-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 10/30/2023] [Indexed: 12/02/2023]
Abstract
The chemotherapeutic agent CX-5461, or pidnarulex, has been fast-tracked by the United States Food and Drug Administration for early-stage clinical studies of BRCA1-, BRCA2- and PALB2-mutated cancers. It is under investigation in phase I and II trials. Here, we find that, although CX-5461 exhibits synthetic lethality in BRCA1-/BRCA2-deficient cells, it also causes extensive, nonselective, collateral mutagenesis in all three cell lines tested, to magnitudes that exceed known environmental carcinogens.
Collapse
Affiliation(s)
- Gene Ching Chiek Koh
- Department of Oncology, Early Cancer Institute, University of Cambridge, Cambridge, UK
- Academic Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Soraya Boushaki
- Academic Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Salome Jingchen Zhao
- Academic Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Andrew Marcel Pregnall
- Academic Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Firas Sadiyah
- Department of Oncology, Early Cancer Institute, University of Cambridge, Cambridge, UK
- Academic Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Cherif Badja
- Department of Oncology, Early Cancer Institute, University of Cambridge, Cambridge, UK
- Academic Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Yasin Memari
- Department of Oncology, Early Cancer Institute, University of Cambridge, Cambridge, UK
- Academic Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Ilias Georgakopoulos-Soares
- Department of Biochemistry and Molecular Biology, Institute for Personalized Medicine, The Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Serena Nik-Zainal
- Department of Oncology, Early Cancer Institute, University of Cambridge, Cambridge, UK.
- Academic Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, UK.
| |
Collapse
|
4
|
Baniulyte G, Durham SA, Merchant LE, Sammons MA. Shared Gene Targets of the ATF4 and p53 Transcriptional Networks. Mol Cell Biol 2023; 43:426-449. [PMID: 37533313 PMCID: PMC10448979 DOI: 10.1080/10985549.2023.2229225] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 06/12/2023] [Accepted: 06/20/2023] [Indexed: 08/04/2023] Open
Abstract
The master tumor suppressor p53 regulates multiple cell fate decisions, such as cell cycle arrest and apoptosis, via transcriptional control of a broad gene network. Dysfunction in the p53 network is common in cancer, often through mutations that inactivate p53 or other members of the pathway. Induction of tumor-specific cell death by restoration of p53 activity without off-target effects has gained significant interest in the field. In this study, we explore the gene regulatory mechanisms underlying a putative anticancer strategy involving stimulation of the p53-independent integrated stress response (ISR). Our data demonstrate the p53 and ISR pathways converge to independently regulate common metabolic and proapoptotic genes. We investigated the architecture of multiple gene regulatory elements bound by p53 and the ISR effector ATF4 controlling this shared regulation. We identified additional key transcription factors that control basal and stress-induced regulation of these shared p53 and ATF4 target genes. Thus, our results provide significant new molecular and genetic insight into gene regulatory networks and transcription factors that are the target of numerous antitumor therapies.
Collapse
Affiliation(s)
- Gabriele Baniulyte
- Department of Biological Sciences, The RNA Institute, University at Albany, State University of New York, Albany, New York, USA
| | - Serene A. Durham
- Department of Biological Sciences, The RNA Institute, University at Albany, State University of New York, Albany, New York, USA
| | - Lauren E. Merchant
- Department of Biological Sciences, The RNA Institute, University at Albany, State University of New York, Albany, New York, USA
| | - Morgan A. Sammons
- Department of Biological Sciences, The RNA Institute, University at Albany, State University of New York, Albany, New York, USA
| |
Collapse
|
5
|
Casimir L, Zimmer S, Racine-Brassard F, Goudreau F, Jacques PÉ, Maréchal A. Chronic treatment with ATR and CHK1 inhibitors does not substantially increase the mutational burden of human cells. Mutat Res 2023; 827:111834. [PMID: 37531716 DOI: 10.1016/j.mrfmmm.2023.111834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 07/13/2023] [Accepted: 07/19/2023] [Indexed: 08/04/2023]
Abstract
DNA replication stress (RS) entails the frequent slow down and arrest of replication forks by a variety of conditions that hinder accurate and processive genome duplication. Elevated RS leads to genome instability, replication catastrophe and eventually cell death. RS is particularly prevalent in cancer cells and its exacerbation to unsustainable levels by chemotherapeutic agents remains a cornerstone of cancer treatments. The adverse consequences of RS are normally prevented by the ATR and CHK1 checkpoint kinases that stabilize stressed forks, suppress origin firing and promote cell cycle arrest when replication is perturbed. Specific inhibitors of these kinases have been developed and shown to potentiate RS and cell death in multiple in vitro cancer settings. Ongoing clinical trials are now probing their efficacy against various cancer types, either as single agents or in combination with mainstay chemotherapeutics. Despite their promise as valuable additions to the anti-cancer pharmacopoeia, we still lack a genome-wide view of the potential mutagenicity of these new drugs. To investigate this question, we performed chronic long-term treatments of TP53-depleted human cancer cells with ATR and CHK1 inhibitors (ATRi, AZD6738/ceralasertib and CHK1i, MK8776/SCH-900776). ATR or CHK1 inhibition did not significantly increase the mutational burden of cells, nor generate specific mutational signatures. Indeed, no notable changes in the numbers of base substitutions, short insertions/deletions and larger scale rearrangements were observed despite induction of replication-associated DNA breaks during treatments. Interestingly, ATR inhibition did induce a slight increase in closely-spaced mutations, a feature previously attributed to translesion synthesis DNA polymerases. The results suggest that ATRi and CHK1i do not have substantial mutagenic effects in vitro when used as standalone agents.
Collapse
Affiliation(s)
- Lisa Casimir
- Département de Biologie, Université de Sherbrooke, Sherbrooke J1K 2R1, QC, Canada; Institut de Recherche sur le Cancer de l'Université de Sherbrooke (IRCUS), Sherbrooke J1K 2R1, QC, Canada
| | - Samuel Zimmer
- Département de Biologie, Université de Sherbrooke, Sherbrooke J1K 2R1, QC, Canada; Institut de Recherche sur le Cancer de l'Université de Sherbrooke (IRCUS), Sherbrooke J1K 2R1, QC, Canada
| | - Félix Racine-Brassard
- Département de Biologie, Université de Sherbrooke, Sherbrooke J1K 2R1, QC, Canada; Institut de Recherche sur le Cancer de l'Université de Sherbrooke (IRCUS), Sherbrooke J1K 2R1, QC, Canada
| | - Félix Goudreau
- Département de Biologie, Université de Sherbrooke, Sherbrooke J1K 2R1, QC, Canada; Institut de Recherche sur le Cancer de l'Université de Sherbrooke (IRCUS), Sherbrooke J1K 2R1, QC, Canada
| | - Pierre-Étienne Jacques
- Département de Biologie, Université de Sherbrooke, Sherbrooke J1K 2R1, QC, Canada; Institut de Recherche sur le Cancer de l'Université de Sherbrooke (IRCUS), Sherbrooke J1K 2R1, QC, Canada; Centre de recherche du Centre hospitalier universitaire de Sherbrooke (CRCHUS), Sherbrooke J1H 5N3, QC, Canada.
| | - Alexandre Maréchal
- Département de Biologie, Université de Sherbrooke, Sherbrooke J1K 2R1, QC, Canada; Institut de Recherche sur le Cancer de l'Université de Sherbrooke (IRCUS), Sherbrooke J1K 2R1, QC, Canada; Centre de recherche du Centre hospitalier universitaire de Sherbrooke (CRCHUS), Sherbrooke J1H 5N3, QC, Canada.
| |
Collapse
|
6
|
Baniulyte G, Durham SA, Merchant LE, Sammons MA. Shared gene targets of the ATF4 and p53 transcriptional networks. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.15.532778. [PMID: 36993734 PMCID: PMC10055071 DOI: 10.1101/2023.03.15.532778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The master tumor suppressor p53 regulates multiple cell fate decisions, like cell cycle arrest and apoptosis, via transcriptional control of a broad gene network. Dysfunction in the p53 network is common in cancer, often through mutations that inactivate p53 or other members of the pathway. Induction of tumor-specific cell death by restoration of p53 activity without off-target effects has gained significant interest in the field. In this study, we explore the gene regulatory mechanisms underlying a putative anti-cancer strategy involving stimulation of the p53-independent Integrated Stress Response (ISR). Our data demonstrate the p53 and ISR pathways converge to independently regulate common metabolic and pro-apoptotic genes. We investigated the architecture of multiple gene regulatory elements bound by p53 and the ISR effector ATF4 controlling this shared regulation. We identified additional key transcription factors that control basal and stress-induced regulation of these shared p53 and ATF4 target genes. Thus, our results provide significant new molecular and genetic insight into gene regulatory networks and transcription factors that are the target of numerous antitumor therapies.
Collapse
Affiliation(s)
- Gabriele Baniulyte
- Department of Biological Sciences and The RNA Institute, University at Albany, State University of New York, Albany, NY, USA
| | - Serene A. Durham
- Department of Biological Sciences and The RNA Institute, University at Albany, State University of New York, Albany, NY, USA
| | - Lauren E. Merchant
- Department of Biological Sciences and The RNA Institute, University at Albany, State University of New York, Albany, NY, USA
| | - Morgan A. Sammons
- Department of Biological Sciences and The RNA Institute, University at Albany, State University of New York, Albany, NY, USA
| |
Collapse
|
7
|
Llargués-Sistac G, Bonjoch L, Castellvi-Bel S. HAP1, a new revolutionary cell model for gene editing using CRISPR-Cas9. Front Cell Dev Biol 2023; 11:1111488. [PMID: 36936678 PMCID: PMC10020200 DOI: 10.3389/fcell.2023.1111488] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 02/22/2023] [Indexed: 03/06/2023] Open
Abstract
The use of next-generation sequencing (NGS) technologies has been instrumental in the characterization of the mutational landscape of complex human diseases like cancer. But despite the enormous rise in the identification of disease candidate genetic variants, their functionality is yet to be fully elucidated in order to have a clear implication in patient care. Haploid human cell models have become the tool of choice for functional gene studies, since they only contain one copy of the genome and can therefore show the unmasked phenotype of genetic variants. Over the past few years, the human near-haploid cell line HAP1 has widely been consolidated as one of the favorite cell line models for functional genetic studies. Its rapid turnover coupled with the fact that only one allele needs to be modified in order to express the subsequent desired phenotype has made this human cell line a valuable tool for gene editing by CRISPR-Cas9 technologies. This review examines the recent uses of the HAP1 cell line model in functional genetic studies and high-throughput genetic screens using the CRISPR-Cas9 system. It covers its use in an attempt to develop new and relevant disease models to further elucidate gene function, and create new ways to understand the genetic basis of human diseases. We will cover the advantages and potential of the use of CRISPR-Cas9 technology on HAP1 to easily and efficiently study the functional interpretation of gene function and human single-nucleotide genetic variants of unknown significance identified through NGS technologies, and its implications for changes in clinical practice and patient care.
Collapse
|
8
|
Thakkar MK, Lee J, Meyer S, Chang VY. RecQ Helicase Somatic Alterations in Cancer. Front Mol Biosci 2022; 9:887758. [PMID: 35782872 PMCID: PMC9240438 DOI: 10.3389/fmolb.2022.887758] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/23/2022] [Indexed: 11/13/2022] Open
Abstract
Named the “caretakers” of the genome, RecQ helicases function in several pathways to maintain genomic stability and repair DNA. This highly conserved family of enzymes consist of five different proteins in humans: RECQL1, BLM, WRN, RECQL4, and RECQL5. Biallelic germline mutations in BLM, WRN, and RECQL4 have been linked to rare cancer-predisposing syndromes. Emerging research has also implicated somatic alterations in RecQ helicases in a variety of cancers, including hematological malignancies, breast cancer, osteosarcoma, amongst others. These alterations in RecQ helicases, particularly overexpression, may lead to increased resistance of cancer cells to conventional chemotherapy. Downregulation of these proteins may allow for increased sensitivity to chemotherapy, and, therefore, may be important therapeutic targets. Here we provide a comprehensive review of our current understanding of the role of RecQ DNA helicases in cancer and discuss the potential therapeutic opportunities in targeting these helicases.
Collapse
Affiliation(s)
- Megha K. Thakkar
- Department of Pediatrics, Division of Pediatric Hematology-Oncology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Jamie Lee
- Department of Pediatrics, Division of Pediatric Hematology-Oncology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Stefan Meyer
- Division of Cancer Studies, University of Manchester, Manchester, United Kingdom
- Department of Pediatric Hematology Oncology, Royal Manchester Children’s Hospital and Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Vivian Y. Chang
- Department of Pediatrics, Division of Pediatric Hematology-Oncology, University of California, Los Angeles, Los Angeles, CA, United States
- Childrens Discovery and Innovation Institute, UCLA, Los Angeles, CA, United States
- Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA, United States
- *Correspondence: Vivian Y. Chang,
| |
Collapse
|
9
|
Maity J, Horibata S, Zurcher G, Lee JM. Targeting of RecQ Helicases as a Novel Therapeutic Strategy for Ovarian Cancer. Cancers (Basel) 2022; 14:cancers14051219. [PMID: 35267530 PMCID: PMC8909030 DOI: 10.3390/cancers14051219] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 11/16/2022] Open
Abstract
RecQ helicases are essential for DNA replication, recombination, DNA damage repair, and other nucleic acid metabolic pathways required for normal cell growth, survival, and genome stability. More recently, RecQ helicases have been shown to be important for replication fork stabilization, one of the major mechanisms of PARP inhibitor resistance. Cancer cells often have upregulated helicases and depend on these enzymes to repair rapid growth-promoted DNA lesions. Several studies are now evaluating the use of RecQ helicases as potential biomarkers of breast and gynecologic cancers. Furthermore, RecQ helicases have attracted interest as possible targets for cancer treatment. In this review, we discuss the characteristics of RecQ helicases and their interacting partners that may be utilized for effective treatment strategies (as cancers depend on helicases for survival). We also discuss how targeting helicase in combination with DNA repair inhibitors (i.e., PARP and ATR inhibitors) can be used as novel approaches for cancer treatment to increase sensitivity to current treatment to prevent rise of treatment resistance.
Collapse
Affiliation(s)
- Jyotirindra Maity
- Women’s Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (J.M.); (G.Z.)
| | - Sachi Horibata
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
- Precision Health Program, Michigan State University, East Lansing, MI 48824, USA
- Department of Pharmacology and Toxicology, College of Human Medicine, Michigan State University, East Lansing, MI 48824, USA
- Correspondence: (S.H.); (J.M.L.)
| | - Grant Zurcher
- Women’s Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (J.M.); (G.Z.)
| | - Jung-Min Lee
- Women’s Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (J.M.); (G.Z.)
- Correspondence: (S.H.); (J.M.L.)
| |
Collapse
|
10
|
Ball CB, Parida M, Santana JF, Spector BM, Suarez GA, Price DH. Nuclear export restricts Gdown1 to a mitotic function. Nucleic Acids Res 2022; 50:1908-1926. [PMID: 35048979 PMCID: PMC8887472 DOI: 10.1093/nar/gkac015] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 12/22/2021] [Accepted: 01/14/2022] [Indexed: 01/11/2023] Open
Abstract
Approximately half of purified mammalian RNA polymerase II (Pol II) is associated with a tightly interacting sub-stoichiometric subunit, Gdown1. Previous studies have established that Gdown1 inhibits transcription initiation through competitive interactions with general transcription factors and blocks the Pol II termination activity of transcription termination factor 2 (TTF2). However, the biological functions of Gdown1 remain poorly understood. Here, we utilized genetic, microscopic, and multi-omics approaches to functionally characterize Gdown1 in three human cell lines. Acute depletion of Gdown1 caused minimal direct effects on transcription. We show that Gdown1 resides predominantly in the cytoplasm of interphase cells, shuttles between the cytoplasm and nucleus, and is regulated by nuclear export. Gdown1 enters the nucleus at the onset of mitosis. Consistently, genetic ablation of Gdown1 is associated with partial de-repression of mitotic transcription, and Gdown1 KO cells present with evidence of aberrant mitoses coupled to p53 pathway activation. Evidence is presented demonstrating that Gdown1 modulates the combined functions of purified productive elongation factors PAF1C, RTF1, SPT6, DSIF and P-TEFb in vitro. Collectively, our findings support a model wherein the Pol II-regulatory function of Gdown1 occurs during mitosis and is required for genome integrity.
Collapse
Affiliation(s)
- Christopher B Ball
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Mrutyunjaya Parida
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Juan F Santana
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Benjamin M Spector
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Gustavo A Suarez
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - David H Price
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| |
Collapse
|
11
|
Hambarde S, Tsai CL, Pandita RK, Bacolla A, Maitra A, Charaka V, Hunt CR, Kumar R, Limbo O, Le Meur R, Chazin WJ, Tsutakawa SE, Russell P, Schlacher K, Pandita TK, Tainer JA. EXO5-DNA structure and BLM interactions direct DNA resection critical for ATR-dependent replication restart. Mol Cell 2021; 81:2989-3006.e9. [PMID: 34197737 PMCID: PMC8720176 DOI: 10.1016/j.molcel.2021.05.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 04/09/2021] [Accepted: 05/24/2021] [Indexed: 02/07/2023]
Abstract
Stalled DNA replication fork restart after stress as orchestrated by ATR kinase, BLM helicase, and structure-specific nucleases enables replication, cell survival, and genome stability. Here we unveil human exonuclease V (EXO5) as an ATR-regulated DNA structure-specific nuclease and BLM partner for replication fork restart. We find that elevated EXO5 in tumors correlates with increased mutation loads and poor patient survival, suggesting that EXO5 upregulation has oncogenic potential. Structural, mechanistic, and mutational analyses of EXO5 and EXO5-DNA complexes reveal a single-stranded DNA binding channel with an adjacent ATR phosphorylation motif (T88Q89) that regulates EXO5 nuclease activity and BLM binding identified by mass spectrometric analysis. EXO5 phospho-mimetic mutant rescues the restart defect from EXO5 depletion that decreases fork progression, DNA damage repair, and cell survival. EXO5 depletion furthermore rescues survival of FANCA-deficient cells and indicates EXO5 functions epistatically with SMARCAL1 and BLM. Thus, an EXO5 axis connects ATR and BLM in directing replication fork restart.
Collapse
Affiliation(s)
- Shashank Hambarde
- Department of Radiation Oncology, The Houston Methodist Research Institute, Houston, TX 77030, USA; Department of Neurosurgery, The Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Chi-Lin Tsai
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Raj K Pandita
- Department of Radiation Oncology, The Houston Methodist Research Institute, Houston, TX 77030, USA; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Albino Bacolla
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Anirban Maitra
- Sheikh Ahmed Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Vijay Charaka
- Department of Radiation Oncology, The Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Clayton R Hunt
- Department of Radiation Oncology, The Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Rakesh Kumar
- School of Biotechnology, Shri Mata Vashino Devi University, Katra, Jammu and Kashmir, 182320, India
| | - Oliver Limbo
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Remy Le Meur
- Departments of Biochemistry and Chemistry and Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Walter J Chazin
- Departments of Biochemistry and Chemistry and Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Susan E Tsutakawa
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Paul Russell
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Katharina Schlacher
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Tej K Pandita
- Department of Radiation Oncology, The Houston Methodist Research Institute, Houston, TX 77030, USA; Department of Neurosurgery, The Houston Methodist Research Institute, Houston, TX 77030, USA; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
| | - John A Tainer
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| |
Collapse
|
12
|
Sharp MF, Bythell-Douglas R, Deans AJ, Crismani W. The Fanconi anemia ubiquitin E3 ligase complex as an anti-cancer target. Mol Cell 2021; 81:2278-2289. [PMID: 33984284 DOI: 10.1016/j.molcel.2021.04.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 03/27/2021] [Accepted: 04/21/2021] [Indexed: 10/21/2022]
Abstract
Agents that induce DNA damage can cure some cancers. However, the side effects of chemotherapy are severe because of the indiscriminate action of DNA-damaging agents on both healthy and cancerous cells. DNA repair pathway inhibition provides a less toxic and targeted alternative to chemotherapy. A compelling DNA repair target is the Fanconi anemia (FA) E3 ligase core complex due to its critical-and likely singular-role in the efficient removal of specific DNA lesions. FA pathway inactivation has been demonstrated to specifically kill some types of cancer cells without the addition of exogenous DNA damage, including cells that lack BRCA1, BRCA2, ATM, or functionally related genes. In this perspective, we discuss the genetic and biochemical evidence in support of the FA core complex as a compelling drug target for cancer therapy. In particular, we discuss the genetic, biochemical, and structural data that could rapidly advance our capacity to identify and implement the use of FA core complex inhibitors in the clinic.
Collapse
Affiliation(s)
- Michael F Sharp
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia; Department of Medicine (St. Vincent's), University of Melbourne, Fitzroy, VIC, Australia
| | - Wayne Crismani
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia; Department of Medicine (St. Vincent's), University of Melbourne, Fitzroy, VIC, Australia.
| |
Collapse
|
13
|
SLFN11 promotes stalled fork degradation that underlies the phenotype in Fanconi anemia cells. Blood 2021; 137:336-348. [PMID: 32735670 DOI: 10.1182/blood.2019003782] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 07/22/2020] [Indexed: 12/11/2022] Open
Abstract
Fanconi anemia (FA) is a hereditary disorder caused by mutations in any 1 of 22 FA genes. The disease is characterized by hypersensitivity to interstrand crosslink (ICL) inducers such as mitomycin C (MMC). In addition to promoting ICL repair, FA proteins such as RAD51, BRCA2, or FANCD2 protect stalled replication forks from nucleolytic degradation during replication stress, which may have a profound impact on FA pathophysiology. Recent studies showed that expression of the putative DNA/RNA helicase SLFN11 in cancer cells correlates with cell death on chemotherapeutic treatment. However, the underlying mechanisms of SLFN11-mediated DNA damage sensitivity remain unclear. Because SLFN11 expression is high in hematopoietic stem cells, we hypothesized that SLFN11 depletion might ameliorate the phenotypes of FA cells. Here we report that SLFN11 knockdown in the FA patient-derived FANCD2-deficient PD20 cell line improved cell survival on treatment with ICL inducers. FANCD2-/-SLFN11-/- HAP1 cells also displayed phenotypic rescue, including reduced levels of MMC-induced chromosome breakage compared with FANCD2-/- cells. Importantly, we found that SLFN11 promotes extensive fork degradation in FANCD2-/- cells. The degradation process is mediated by the nucleases MRE11 or DNA2 and depends on the SLFN11 ATPase activity. This observation was accompanied by an increased RAD51 binding at stalled forks, consistent with the role of RAD51 antagonizing nuclease recruitment and subsequent fork degradation. Suppression of SLFN11 protects nascent DNA tracts even in wild-type cells. We conclude that SLFN11 destabilizes stalled replication forks, and this function may contribute to the attrition of hematopoietic stem cells in FA.
Collapse
|
14
|
Kaur E, Agrawal R, Sengupta S. Functions of BLM Helicase in Cells: Is It Acting Like a Double-Edged Sword? Front Genet 2021; 12:634789. [PMID: 33777104 PMCID: PMC7994599 DOI: 10.3389/fgene.2021.634789] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 02/11/2021] [Indexed: 12/14/2022] Open
Abstract
DNA damage repair response is an important biological process involved in maintaining the fidelity of the genome in eukaryotes and prokaryotes. Several proteins that play a key role in this process have been identified. Alterations in these key proteins have been linked to different diseases including cancer. BLM is a 3′−5′ ATP-dependent RecQ DNA helicase that is one of the most essential genome stabilizers involved in the regulation of DNA replication, recombination, and both homologous and non-homologous pathways of double-strand break repair. BLM structure and functions are known to be conserved across many species like yeast, Drosophila, mouse, and human. Genetic mutations in the BLM gene cause a rare, autosomal recessive disorder, Bloom syndrome (BS). BS is a monogenic disease characterized by genomic instability, premature aging, predisposition to cancer, immunodeficiency, and pulmonary diseases. Hence, these characteristics point toward BLM being a tumor suppressor. However, in addition to mutations, BLM gene undergoes various types of alterations including increase in the copy number, transcript, and protein levels in multiple types of cancers. These results, along with the fact that the lack of wild-type BLM in these cancers has been associated with increased sensitivity to chemotherapeutic drugs, indicate that BLM also has a pro-oncogenic function. While a plethora of studies have reported the effect of BLM gene mutations in various model organisms, there is a dearth in the studies undertaken to investigate the effect of its oncogenic alterations. We propose to rationalize and integrate the dual functions of BLM both as a tumor suppressor and maybe as a proto-oncogene, and enlist the plausible mechanisms of its deregulation in cancers.
Collapse
Affiliation(s)
- Ekjot Kaur
- Signal Transduction Laboratory-2, National Institute of Immunology, New Delhi, India
| | - Ritu Agrawal
- Signal Transduction Laboratory-2, National Institute of Immunology, New Delhi, India
| | - Sagar Sengupta
- Signal Transduction Laboratory-2, National Institute of Immunology, New Delhi, India
| |
Collapse
|
15
|
Henkel L, Rauscher B, Schmitt B, Winter J, Boutros M. Genome-scale CRISPR screening at high sensitivity with an empirically designed sgRNA library. BMC Biol 2020; 18:174. [PMID: 33228647 PMCID: PMC7686728 DOI: 10.1186/s12915-020-00905-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 10/20/2020] [Indexed: 12/22/2022] Open
Abstract
Background In recent years, large-scale genetic screens using the CRISPR/Cas9 system have emerged as scalable approaches able to interrogate gene function with unprecedented efficiency and specificity in various biological contexts. By this means, functional dependencies on both the protein-coding and noncoding genome of numerous cell types in different organisms have been interrogated. However, screening designs vary greatly and criteria for optimal experimental implementation and library composition are still emerging. Given their broad utility in functionally annotating genomes, the application and interpretation of genome-scale CRISPR screens would greatly benefit from consistent and optimal design criteria. Results We report advantages of conducting viability screens in selected Cas9 single-cell clones in contrast to Cas9 bulk populations. We further systematically analyzed published CRISPR screens in human cells to identify single-guide (sg) RNAs with consistent high on-target and low off-target activity. Selected guides were collected in a novel genome-scale sgRNA library, which efficiently identifies core and context-dependent essential genes. Conclusion We show how empirically designed libraries in combination with an optimized experimental design increase the dynamic range in gene essentiality screens at reduced library coverage. Supplementary information The online version contains supplementary material available at 10.1186/s12915-020-00905-1.
Collapse
Affiliation(s)
- Luisa Henkel
- German Cancer Research Center (DKFZ), Division Signaling and Functional Genomics and Heidelberg University, BioQuant and Medical Faculty Mannheim, D-69120, Heidelberg, Germany
| | - Benedikt Rauscher
- German Cancer Research Center (DKFZ), Division Signaling and Functional Genomics and Heidelberg University, BioQuant and Medical Faculty Mannheim, D-69120, Heidelberg, Germany
| | - Barbara Schmitt
- German Cancer Research Center (DKFZ), Division Signaling and Functional Genomics and Heidelberg University, BioQuant and Medical Faculty Mannheim, D-69120, Heidelberg, Germany
| | - Jan Winter
- German Cancer Research Center (DKFZ), Division Signaling and Functional Genomics and Heidelberg University, BioQuant and Medical Faculty Mannheim, D-69120, Heidelberg, Germany
| | - Michael Boutros
- German Cancer Research Center (DKFZ), Division Signaling and Functional Genomics and Heidelberg University, BioQuant and Medical Faculty Mannheim, D-69120, Heidelberg, Germany.
| |
Collapse
|
16
|
Kobaisi F, Fayyad N, Sulpice E, Badran B, Fayyad-Kazan H, Rachidi W, Gidrol X. High-throughput synthetic rescue for exhaustive characterization of suppressor mutations in human genes. Cell Mol Life Sci 2020; 77:4209-4222. [PMID: 32270227 PMCID: PMC7588364 DOI: 10.1007/s00018-020-03519-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 03/21/2020] [Accepted: 03/30/2020] [Indexed: 02/06/2023]
Abstract
Inherited or acquired mutations can lead to pathological outcomes. However, in a process defined as synthetic rescue, phenotypic outcome created by primary mutation is alleviated by suppressor mutations. An exhaustive characterization of these mutations in humans is extremely valuable to better comprehend why patients carrying the same detrimental mutation exhibit different pathological outcomes or different responses to treatment. Here, we first review all known suppressor mutations' mechanisms characterized by genetic screens on model species like yeast or flies. However, human suppressor mutations are scarce, despite some being discovered based on orthologue genes. Because of recent advances in high-throughput screening, developing an inventory of human suppressor mutations for pathological processes seems achievable. In addition, we review several screening methods for suppressor mutations in cultured human cells through knock-out, knock-down or random mutagenesis screens on large scale. We provide examples of studies published over the past years that opened new therapeutic avenues, particularly in oncology.
Collapse
Affiliation(s)
- Farah Kobaisi
- University of Grenoble Alpes, CEA, INSERM, IRIG-BGE U1038, 38000, Grenoble, France
- Laboratory of Cancer Biology and Molecular Immunology, Faculty of Sciences I, Lebanese University, Hadath, Lebanon
- University of Grenoble Alpes, SYMMES/CIBEST UMR 5819 UGA-CNRS-CEA, IRIG/CEA-Grenoble, Grenoble, France
| | - Nour Fayyad
- University of Grenoble Alpes, SYMMES/CIBEST UMR 5819 UGA-CNRS-CEA, IRIG/CEA-Grenoble, Grenoble, France
| | - Eric Sulpice
- University of Grenoble Alpes, CEA, INSERM, IRIG-BGE U1038, 38000, Grenoble, France
| | - Bassam Badran
- Laboratory of Cancer Biology and Molecular Immunology, Faculty of Sciences I, Lebanese University, Hadath, Lebanon
| | - Hussein Fayyad-Kazan
- Laboratory of Cancer Biology and Molecular Immunology, Faculty of Sciences I, Lebanese University, Hadath, Lebanon
| | - Walid Rachidi
- University of Grenoble Alpes, SYMMES/CIBEST UMR 5819 UGA-CNRS-CEA, IRIG/CEA-Grenoble, Grenoble, France
| | - Xavier Gidrol
- University of Grenoble Alpes, CEA, INSERM, IRIG-BGE U1038, 38000, Grenoble, France.
| |
Collapse
|
17
|
Xue VW, Wong SCC, Cho WCS. Genome-wide CRISPR screens for the identification of therapeutic targets for cancer treatment. Expert Opin Ther Targets 2020; 24:1147-1158. [PMID: 32893711 DOI: 10.1080/14728222.2020.1820986] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
INTRODUCTION Exploring the function of every gene is a challenging task. There is a paradigm shift of RNA interference with the introduction of clustered regularly interspaced short palindromic repeat (CRISPR)-based genome-wide screening. CRISPR-based screening can detect the loss-of-function and gain-of-function targets. Many DNA-binding proteins are engineered as effective tools for modulating gene expression and for investigating therapeutic targets for a spectrum of diseases. Among them, CRISPR-Cas9 has received extensive attention with its potential for screening cancer treatment targets. AREAS COVERED This article reviews CRISPR toolkit and its applications in screening cancer therapeutic targets, especially genome-wide screens using different CRISPR-Cas9 systems. We compare and summarize the characteristics of CRISPR systems, which would be helpful for understanding and optimizing current CRISPR toolkits, as well as reflecting on the potential future development and clinical applications of CRISPR screens. EXPERT OPINION The application of CRISPR-based therapeutic target screening is broadly used in cancer drug development. Its application in cancer immunotherapy and precision oncology is blooming. Nevertheless, more effective methods of Cas protein delivery and the development of more accurate and efficient genome-editing tools are needed.
Collapse
Affiliation(s)
- Vivian Weiwen Xue
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, The Chinese University of Hong Kong , Hong Kong, China
| | - Sze Chuen Cesar Wong
- Department of Health Technology and Informatics, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University , Hong Kong, China
| | | |
Collapse
|
18
|
Rickman KA, Noonan RJ, Lach FP, Sridhar S, Wang AT, Abhyankar A, Huang A, Kelly M, Auerbach AD, Smogorzewska A. Distinct roles of BRCA2 in replication fork protection in response to hydroxyurea and DNA interstrand cross-links. Genes Dev 2020; 34:832-846. [PMID: 32354836 PMCID: PMC7263144 DOI: 10.1101/gad.336446.120] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 04/01/2020] [Indexed: 02/07/2023]
Abstract
DNA interstrand cross-links (ICLs) are a form of DNA damage that requires the interplay of a number of repair proteins including those of the Fanconi anemia (FA) and the homologous recombination (HR) pathways. Pathogenic variants in the essential gene BRCA2/FANCD1, when monoallelic, predispose to breast and ovarian cancer, and when biallelic, result in a severe subtype of Fanconi anemia. BRCA2 function in the FA pathway is attributed to its role as a mediator of the RAD51 recombinase in HR repair of programmed DNA double-strand breaks (DSB). BRCA2 and RAD51 functions are also required to protect stalled replication forks from nucleolytic degradation during response to hydroxyurea (HU). While RAD51 has been shown to be necessary in the early steps of ICL repair to prevent aberrant nuclease resection, the role of BRCA2 in this process has not been described. Here, based on the analysis of BRCA2 DNA-binding domain (DBD) mutants (c.8488-1G>A and c.8524C>T) discovered in FA patients presenting with atypical FA-like phenotypes, we establish that BRCA2 is necessary for the protection of DNA at ICLs. Cells carrying BRCA2 DBD mutations are sensitive to ICL-inducing agents but resistant to HU treatment consistent with relatively high HR repair in these cells. BRCA2 function at an ICL protects against DNA2-WRN nuclease-helicase complex and not the MRE11 nuclease that is implicated in the resection of HU-induced stalled replication forks. Our results also indicate that unlike the processing at HU-induced stalled forks, the function of the SNF2 translocases (SMARCAL1, ZRANB3, or HLTF), implicated in fork reversal, are not an integral component of the ICL repair, pointing to a different mechanism of fork protection at different DNA lesions.
Collapse
Affiliation(s)
- Kimberly A Rickman
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Raymond J Noonan
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Francis P Lach
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Sunandini Sridhar
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Anderson T Wang
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | | | - Athena Huang
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| | - Michael Kelly
- Tufts Medical Center, Boston, Massachusetts 02111, USA
| | - Arleen D Auerbach
- Human Genetics and Hematology, The Rockefeller University, New York, New York 10065, USA
| | - Agata Smogorzewska
- Laboratory of Genome Maintenance, The Rockefeller University, New York, New York 10065, USA
| |
Collapse
|
19
|
O'Rourke JJ, Bythell-Douglas R, Dunn EA, Deans AJ. ALT control, delete: FANCM as an anti-cancer target in Alternative Lengthening of Telomeres. Nucleus 2020; 10:221-230. [PMID: 31663812 PMCID: PMC6949022 DOI: 10.1080/19491034.2019.1685246] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Break-induced replication is a specific type of DNA repair that has a co-opted role in telomere extension by telomerase-negative cancer cells. This Alternative Lengthening of Telomeres (or ‘ALT’) is required for viability in approximately 10% of all carcinomas, but up to 50% of the soft-tissue derived sarcomas. In several recent studies, we and others demonstrate that expression and activity of FANCM, a DNA translocase protein, is essential for the viability of ALT-associated cancers. Here we provide a summary of how and why FANCM depletion leads to deletion of ALT-controlled cancers, predominantly through a hyper-activation of break-induced replication. We also discuss how FANCM can and has been targeted in cancer cell killing, including potential opportunities in ALT and other genetic backgrounds.
Collapse
Affiliation(s)
- Julienne J O'Rourke
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine, (St Vincent's) University of Melbourne, Fitzroy, Australia
| | - Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Australia
| | - Elyse A Dunn
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Australia
| | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine, (St Vincent's) University of Melbourne, Fitzroy, Australia
| |
Collapse
|
20
|
Gonatopoulos-Pournatzis T, Aregger M, Brown KR, Farhangmehr S, Braunschweig U, Ward HN, Ha KCH, Weiss A, Billmann M, Durbic T, Myers CL, Blencowe BJ, Moffat J. Genetic interaction mapping and exon-resolution functional genomics with a hybrid Cas9-Cas12a platform. Nat Biotechnol 2020; 38:638-648. [PMID: 32249828 DOI: 10.1038/s41587-020-0437-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 01/27/2020] [Indexed: 12/11/2022]
Abstract
Systematic mapping of genetic interactions (GIs) and interrogation of the functions of sizable genomic segments in mammalian cells represent important goals of biomedical research. To advance these goals, we present a CRISPR (clustered regularly interspaced short palindromic repeats)-based screening system for combinatorial genetic manipulation that employs coexpression of CRISPR-associated nucleases 9 and 12a (Cas9 and Cas12a) and machine-learning-optimized libraries of hybrid Cas9-Cas12a guide RNAs. This system, named Cas Hybrid for Multiplexed Editing and screening Applications (CHyMErA), outperforms genetic screens using Cas9 or Cas12a editing alone. Application of CHyMErA to the ablation of mammalian paralog gene pairs reveals extensive GIs and uncovers phenotypes normally masked by functional redundancy. Application of CHyMErA in a chemogenetic interaction screen identifies genes that impact cell growth in response to mTOR pathway inhibition. Moreover, by systematically targeting thousands of alternative splicing events, CHyMErA identifies exons underlying human cell line fitness. CHyMErA thus represents an effective screening approach for GI mapping and the functional analysis of sizable genomic regions, such as alternative exons.
Collapse
Affiliation(s)
| | - Michael Aregger
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Kevin R Brown
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Shaghayegh Farhangmehr
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | | | - Henry N Ward
- Bioinformatics and Computational Biology Graduate Program, University of Minnesota, Minneapolis, MN, USA
| | - Kevin C H Ha
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Alexander Weiss
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Maximilian Billmann
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Tanja Durbic
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Chad L Myers
- Bioinformatics and Computational Biology Graduate Program, University of Minnesota, Minneapolis, MN, USA.,Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Benjamin J Blencowe
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada. .,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
| | - Jason Moffat
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada. .,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada. .,Institute for Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.
| |
Collapse
|
21
|
Lau MT, Ghazanfar S, Parkin A, Chou A, Rouaen JR, Littleboy JB, Nessem D, Khuong TM, Nevoltris D, Schofield P, Langley D, Christ D, Yang J, Pajic M, Neely GG. Systematic functional identification of cancer multi-drug resistance genes. Genome Biol 2020; 21:27. [PMID: 32028983 PMCID: PMC7006212 DOI: 10.1186/s13059-020-1940-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 01/20/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Drug resistance is a major obstacle in cancer therapy. To elucidate the genetic factors that regulate sensitivity to anti-cancer drugs, we performed CRISPR-Cas9 knockout screens for resistance to a spectrum of drugs. RESULTS In addition to known drug targets and resistance mechanisms, this study revealed novel insights into drug mechanisms of action, including cellular transporters, drug target effectors, and genes involved in target-relevant pathways. Importantly, we identified ten multi-drug resistance genes, including an uncharacterized gene C1orf115, which we named Required for Drug-induced Death 1 (RDD1). Loss of RDD1 resulted in resistance to five anti-cancer drugs. Finally, targeting RDD1 leads to chemotherapy resistance in mice and low RDD1 expression is associated with poor prognosis in multiple cancers. CONCLUSIONS Together, we provide a functional landscape of resistance mechanisms to a broad range of chemotherapeutic drugs and highlight RDD1 as a new factor controlling multi-drug resistance. This information can guide personalized therapies or instruct rational drug combinations to minimize acquisition of resistance.
Collapse
Affiliation(s)
- Man-Tat Lau
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life & Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
- Genome Editing Initiative, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Shila Ghazanfar
- School of Mathematics and Statistics, The University of Sydney, Sydney, NSW, 2006, Australia
- The Judith and David Coffey Life Lab, Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Ashleigh Parkin
- The Kinghorn Cancer Centre, The Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Angela Chou
- The Kinghorn Cancer Centre, The Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, Sydney, NSW, 2010, Australia
- The University of Sydney, Sydney, NSW, 2006, Australia
| | - Jourdin R Rouaen
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life & Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Jamie B Littleboy
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life & Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Danielle Nessem
- The Kinghorn Cancer Centre, The Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Thang M Khuong
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life & Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Damien Nevoltris
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Peter Schofield
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW, 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, Sydney, NSW, 2010, Australia
| | - David Langley
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Daniel Christ
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW, 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, Sydney, NSW, 2010, Australia
| | - Jean Yang
- School of Mathematics and Statistics, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Marina Pajic
- The Kinghorn Cancer Centre, The Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, Sydney, NSW, 2010, Australia.
- St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, Sydney, NSW, 2010, Australia.
| | - G Gregory Neely
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life & Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia.
- Genome Editing Initiative, The University of Sydney, Sydney, NSW, 2006, Australia.
| |
Collapse
|
22
|
Klebsiella oxytoca enterotoxins tilimycin and tilivalline have distinct host DNA-damaging and microtubule-stabilizing activities. Proc Natl Acad Sci U S A 2019; 116:3774-3783. [PMID: 30808763 PMCID: PMC6397511 DOI: 10.1073/pnas.1819154116] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Human gut microbes form a complex community with vast biosynthetic potential. Microbial products and metabolites released in the gut impact human health and disease. However, defining causative relationships between specific bacterial products and disease initiation and progression remains an immense challenge. This study advances understanding of the functional capacity of the gut microbiota by determining the presence, concentration, and spatial and temporal variability of two enterotoxic metabolites produced by the gut-resident Klebsiella oxytoca. We present a detailed mode of action for the cytotoxins and recapitulate their functionalities in disease models in vivo. The findings provide distinct molecular mechanisms for the enterotoxicity of the metabolites allowing them to act in tandem to damage the intestinal epithelium and cause colitis. Establishing causal links between bacterial metabolites and human intestinal disease is a significant challenge. This study reveals the molecular basis of antibiotic-associated hemorrhagic colitis (AAHC) caused by intestinal resident Klebsiella oxytoca. Colitogenic strains produce the nonribosomal peptides tilivalline and tilimycin. Here, we verify that these enterotoxins are present in the human intestine during active colitis and determine their concentrations in a murine disease model. Although both toxins share a pyrrolobenzodiazepine structure, they have distinct molecular targets. Tilimycin acts as a genotoxin. Its interaction with DNA activates damage repair mechanisms in cultured cells and causes DNA strand breakage and an increased lesion burden in cecal enterocytes of colonized mice. In contrast, tilivalline binds tubulin and stabilizes microtubules leading to mitotic arrest. To our knowledge, this activity is unique for microbiota-derived metabolites of the human intestine. The capacity of both toxins to induce apoptosis in intestinal epithelial cells—a hallmark feature of AAHC—by independent modes of action, strengthens our proposal that these metabolites act collectively in the pathogenicity of colitis.
Collapse
|
23
|
Basbous J, Constantinou A. A tumor suppressive DNA translocase named FANCM. Crit Rev Biochem Mol Biol 2019; 54:27-40. [DOI: 10.1080/10409238.2019.1568963] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jihane Basbous
- Institute of Human Genetics (IGH), Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM), Montpellier, France
| | - Angelos Constantinou
- Institute of Human Genetics (IGH), Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM), Montpellier, France
| |
Collapse
|
24
|
Heyza JR, Lei W, Watza D, Zhang H, Chen W, Back JB, Schwartz AG, Bepler G, Patrick SM. Identification and Characterization of Synthetic Viability with ERCC1 Deficiency in Response to Interstrand Crosslinks in Lung Cancer. Clin Cancer Res 2018; 25:2523-2536. [PMID: 30538112 DOI: 10.1158/1078-0432.ccr-18-3094] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 11/14/2018] [Accepted: 12/06/2018] [Indexed: 12/20/2022]
Abstract
PURPOSE ERCC1/XPF is a DNA endonuclease with variable expression in primary tumor specimens, and has been investigated as a predictive biomarker for efficacy of platinum-based chemotherapy. The failure of clinical trials utilizing ERCC1 expression to predict response to platinum-based chemotherapy suggests additional mechanisms underlying the basic biology of ERCC1 in the response to interstrand crosslinks (ICLs) remain unknown. We aimed to characterize a panel of ERCC1 knockout (Δ) cell lines, where we identified a synthetic viable phenotype in response to ICLs with ERCC1 deficiency. EXPERIMENTAL DESIGN We utilized the CRISPR-Cas9 system to create a panel of ERCC1Δ lung cancer cell lines which we characterized. RESULTS We observe that loss of ERCC1 hypersensitizes cells to cisplatin when wild-type (WT) p53 is retained, whereas there is only modest sensitivity in cell lines that are p53mutant/null. In addition, when p53 is disrupted by CRISPR-Cas9 (p53*) in ERCC1Δ/p53WT cells, there is reduced apoptosis and increased viability after platinum treatment. These results were recapitulated in 2 patient data sets utilizing p53 mutation analysis and ERCC1 expression to assess overall survival. We also show that kinetics of ICL-repair (ICL-R) differ between ERCC1Δ/p53WT and ERCC1Δ/p53* cells. Finally, we provide evidence that cisplatin tolerance in the context of ERCC1 deficiency relies on DNA-PKcs and BRCA1 function. CONCLUSIONS Our findings implicate p53 as a potential confounding variable in clinical assessments of ERCC1 as a platinum biomarker via promoting an environment in which error-prone mechanisms of ICL-R may be able to partially compensate for loss of ERCC1.See related commentary by Friboulet et al., p. 2369.
Collapse
Affiliation(s)
- Joshua R Heyza
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan
| | - Wen Lei
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan
| | - Donovan Watza
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan
| | - Hao Zhang
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan
| | - Wei Chen
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan.,Biostatistics Core, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan
| | - Jessica B Back
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan
| | - Ann G Schwartz
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan
| | - Gerold Bepler
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan.
| | - Steve M Patrick
- Department of Oncology, Karmanos Cancer Institute and Wayne State University, Detroit, Michigan.
| |
Collapse
|
25
|
Abstract
Timely recruitment of DNA damage response proteins to sites of genomic structural lesions is very important for signaling mechanisms to activate appropriate cell cycle checkpoints but also repair the altered DNA sequence to suppress mutagenesis. The eukaryotic cell is characterized by a complex cadre of players and pathways to ensure genomic stability in the face of replication stress or outright genomic insult by endogenous metabolites or environmental agents. Among the key performers are molecular motor DNA unwinding enzymes known as helicases that sense genomic perturbations and separate structured DNA strands so that replacement of a damaged base or sugar-phosphate backbone lesion can occur efficiently. Mutations in the BLM gene encoding the DNA helicase BLM leads to a rare chromosomal instability disorder known as Bloom's syndrome. In a recent paper by the Sengupta lab, BLM's role in the correction of double-strand breaks (DSB), a particularly dangerous form of DNA damage, was investigated. Adding to the complexity, BLM appears to be a key ringmaster of DSB repair as it acts both positively and negatively to regulate correction pathways of high or low fidelity. The FANCJ DNA helicase, mutated in another chromosomal instability disorder known as Fanconi Anemia, is an important player that likely coordinates with BLM in the balancing act. Further studies to dissect the roles of DNA helicases like FANCJ and BLM in DSB repair are warranted.
Collapse
Affiliation(s)
- Srijita Dhar
- a Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health , NIH Biomedical Research Center , Baltimore , MD , USA
| | - Robert M Brosh
- a Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health , NIH Biomedical Research Center , Baltimore , MD , USA
| |
Collapse
|
26
|
Velimezi G, Robinson-Garcia L, Muñoz-Martínez F, Wiegant WW, Ferreira da Silva J, Owusu M, Moder M, Wiedner M, Rosenthal SB, Fisch KM, Moffat J, Menche J, van Attikum H, Jackson SP, Loizou JI. Map of synthetic rescue interactions for the Fanconi anemia DNA repair pathway identifies USP48. Nat Commun 2018; 9:2280. [PMID: 29891926 PMCID: PMC5996029 DOI: 10.1038/s41467-018-04649-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 05/14/2018] [Indexed: 01/26/2023] Open
Abstract
Defects in DNA repair can cause various genetic diseases with severe pathological phenotypes. Fanconi anemia (FA) is a rare disease characterized by bone marrow failure, developmental abnormalities, and increased cancer risk that is caused by defective repair of DNA interstrand crosslinks (ICLs). Here, we identify the deubiquitylating enzyme USP48 as synthetic viable for FA-gene deficiencies by performing genome-wide loss-of-function screens across a panel of human haploid isogenic FA-defective cells (FANCA, FANCC, FANCG, FANCI, FANCD2). Thus, as compared to FA-defective cells alone, FA-deficient cells additionally lacking USP48 are less sensitive to genotoxic stress induced by ICL agents and display enhanced, BRCA1-dependent, clearance of DNA damage. Consequently, USP48 inactivation reduces chromosomal instability of FA-defective cells. Our results highlight a role for USP48 in controlling DNA repair and suggest it as a potential target that could be therapeutically exploited for FA.
Collapse
Affiliation(s)
- Georgia Velimezi
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090, Vienna, Austria
| | - Lydia Robinson-Garcia
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090, Vienna, Austria
| | - Francisco Muñoz-Martínez
- The Gurdon Institute and Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK
| | - Wouter W Wiegant
- Department of Human Genetics, Leiden University Medical Center, Leiden, Einthovenweg 20, 2333 ZC, Leiden, The Netherlands
| | - Joana Ferreira da Silva
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090, Vienna, Austria
| | - Michel Owusu
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090, Vienna, Austria
| | - Martin Moder
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090, Vienna, Austria
| | - Marc Wiedner
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090, Vienna, Austria
| | - Sara Brin Rosenthal
- Center for Computational Biology & Bioinformatics, Department of Medicine, University of California, San Diego, 9500 Gilman Drive #0681, La Jolla, CA, 92093, USA
| | - Kathleen M Fisch
- Center for Computational Biology & Bioinformatics, Department of Medicine, University of California, San Diego, 9500 Gilman Drive #0681, La Jolla, CA, 92093, USA
| | - Jason Moffat
- Donnelly Centre and Banting and Best Department of Medical Research, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Jörg Menche
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090, Vienna, Austria
| | - Haico van Attikum
- Department of Human Genetics, Leiden University Medical Center, Leiden, Einthovenweg 20, 2333 ZC, Leiden, The Netherlands
| | - Stephen P Jackson
- The Gurdon Institute and Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK
| | - Joanna I Loizou
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090, Vienna, Austria.
| |
Collapse
|