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Zhang X, Duan J, Li Y, Jin X, Wu C, Yang X, Lu W, Ge W. NKAP acts with HDAC3 to prevent R-loop associated genome instability. Cell Death Differ 2023; 30:1811-1828. [PMID: 37322264 PMCID: PMC10307950 DOI: 10.1038/s41418-023-01182-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 05/09/2023] [Accepted: 06/07/2023] [Indexed: 06/17/2023] Open
Abstract
Persistent R-loop accumulation can cause DNA damage and lead to genome instability, which contributes to various human diseases. Identification of molecules and signaling pathways in controlling R-loop homeostasis provide important clues about their physiological and pathological roles in cells. Here, we show that NKAP (NF-κB activating protein) is essential for preventing R-loop accumulation and maintaining genome integrity through forming a protein complex with HDAC3. NKAP depletion causes DNA damage and genome instability. Aberrant accumulation of R-loops is present in NKAP-deficient cells and leads to DNA damage and DNA replication fork progression defects. Moreover, NKAP depletion induced R-loops and DNA damage are dependent on transcription. Consistently, the NKAP interacting protein HDAC3 exhibits a similar role in suppressing R-loop associated DNA damage and replication stress. Further analysis uncovers that HDAC3 functions to stabilize NKAP protein, independent of its deacetylase activity. In addition, NKAP prevents R-loop formation by maintaining RNA polymerase II pausing. Importantly, R-loops induced by NKAP or HDAC3 depletion are processed into DNA double-strand breaks by XPF and XPG endonucleases. These findings indicate that both NKAP and HDAC3 are novel key regulators of R-loop homeostasis, and their dysregulation might drive tumorigenesis by causing R-loop associated genome instability.
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Affiliation(s)
- Xing Zhang
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
| | - Jingwei Duan
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
| | - Yang Li
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
- Department of Gynecologic Oncology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
| | - Xiaoye Jin
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
| | - Cheng Wu
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
| | - Xiaohang Yang
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
| | - Weiguo Lu
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China.
- Department of Gynecologic Oncology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China.
- Cancer Center, Zhejiang University, Hangzhou, 310058, Zhejiang, China.
| | - Wanzhong Ge
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China.
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China.
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China.
- Cancer Center, Zhejiang University, Hangzhou, 310058, Zhejiang, China.
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Feng Y, Zhang H, Han J, Cui B, Qin L, Zhang L, Li Q, Wu X, Xiao N, Zhang Y, Lin T, Liu H, Sun T. HSF4/COIL complex-dependent R-loop mediates ultraviolet-induced inflammatory skin injury. Clin Transl Med 2023; 13:e1336. [PMID: 37461263 PMCID: PMC10352565 DOI: 10.1002/ctm2.1336] [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: 12/15/2022] [Revised: 07/05/2023] [Accepted: 07/11/2023] [Indexed: 07/20/2023] Open
Abstract
Intense ultraviolet (UV) exposure can cause phototoxic reactions, such as skin inflammation, resulting in injury. UV is a direct cause of DNA damage, but the mechanisms underlying transcriptional regulation within cells after DNA damage are unclear. The bioinformatics analysis of transcriptome sequencing data from UV-irradiated and non-UV-irradiated skin showed that transcription-related proteins, such as HSF4 and COIL, mediate cellular response to UV irradiation. HSF4 and COIL can form a complex under UV irradiation, and the preference for binding target genes changed because of the presence of a large number of R-loops in cells under UV irradiation and the ability of COIL to recognize R-loops. The regulation of target genes was altered by the HSF4-COIL complex, and the expression of inflammation and ageing-related genes, such as Atg7, Tfpi, and Lims1, was enhanced. A drug screen was performed for the recognition sites of COIL and R-loop. N6-(2-hydroxyethyl)-adenosine can competitively bind COIL and inhibit the binding of COIL to the R-loop. Thus, the activation of downstream inflammation-related genes and inflammatory skin injury was inhibited.
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Affiliation(s)
- Yi‐qian Feng
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
| | - Heng Zhang
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
- Tianjin Key Laboratory of Early Druggability Evaluation of Innovative Drugs and Tianjin Key Laboratory of Molecular Drug ResearchTianjin International Joint Academy of BiomedicineTianjinChina
| | - Jing‐xia Han
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
- Tianjin Key Laboratory of Early Druggability Evaluation of Innovative Drugs and Tianjin Key Laboratory of Molecular Drug ResearchTianjin International Joint Academy of BiomedicineTianjinChina
| | - Bi‐jia Cui
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
| | - Lu‐ning Qin
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
| | - Lei Zhang
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
| | - Qing‐qing Li
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
| | - Xin‐ying Wu
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
| | - Nan‐nan Xiao
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
| | - Yan Zhang
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
| | - Ting‐ting Lin
- Medical Plastic and Cosmetic CentreTianjin Branch of National Clinical Research Center for Ocular DiseaseTianjin Medical University Eye HospitalTianjinChina
| | - Hui‐juan Liu
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
- Tianjin Key Laboratory of Early Druggability Evaluation of Innovative Drugs and Tianjin Key Laboratory of Molecular Drug ResearchTianjin International Joint Academy of BiomedicineTianjinChina
| | - Tao Sun
- State Key Laboratory of Medicinal Chemical Biology and College of PharmacyNankai UniversityTianjinChina
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Pozzi B, Naguleswaran A, Florini F, Rezaei Z, Roditi I. The RNA export factor TbMex67 connects transcription and RNA export in Trypanosoma brucei and sets boundaries for RNA polymerase I. Nucleic Acids Res 2023; 51:5177-5192. [PMID: 37070196 PMCID: PMC10250216 DOI: 10.1093/nar/gkad251] [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: 11/08/2022] [Revised: 03/21/2023] [Accepted: 03/24/2023] [Indexed: 04/19/2023] Open
Abstract
TbMex67 is the major mRNA export factor known to date in trypanosomes, forming part of the docking platform within the nuclear pore. To explore its role in co-transcriptional mRNA export, recently reported in Trypanosoma brucei, pulse labelling of nascent RNAs with 5-ethynyl uridine (5-EU) was performed with cells depleted of TbMex67 and complemented with a dominant-negative mutant (TbMex67-DN). RNA polymerase (Pol) II transcription was unaffected, but the procyclin loci, which encode mRNAs transcribed by Pol I from internal sites on chromosomes 6 and 10, showed increased levels of 5-EU incorporation. This was due to Pol I readthrough transcription, which proceeded beyond the procyclin and procyclin-associated genes up to the Pol II transcription start site on the opposite strand. Complementation by TbMex67-DN also increased Pol I-dependent formation of R-loops and γ-histone 2A foci. The DN mutant exhibited reduced nuclear localisation and binding to chromatin compared to wild-type TbMex67. Together with its interaction with chromatin remodelling factor TbRRM1 and Pol II, and transcription-dependent association of Pol II with nucleoporins, our findings support a role for TbMex67 in connecting transcription and export in T. brucei. In addition, TbMex67 stalls readthrough by Pol I in specific contexts, thereby limiting R-loop formation and replication stress.
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Affiliation(s)
- Berta Pozzi
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | | | | | - Zahra Rezaei
- Professor Alborzi Clinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Isabel Roditi
- Institute of Cell Biology, University of Bern, Bern, Switzerland
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Gatti V, De Domenico S, Melino G, Peschiaroli A. Senataxin and R-loops homeostasis: multifaced implications in carcinogenesis. Cell Death Discov 2023; 9:145. [PMID: 37147318 PMCID: PMC10163015 DOI: 10.1038/s41420-023-01441-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/06/2023] [Accepted: 04/20/2023] [Indexed: 05/07/2023] Open
Abstract
R-loops are inherent byproducts of transcription consisting of an RNA:DNA hybrid and a displaced single-stranded DNA. These structures are of key importance in controlling numerous physiological processes and their homeostasis is tightly controlled by the activities of several enzymes deputed to process R-loops and prevent their unproper accumulation. Senataxin (SETX) is an RNA/DNA helicase which catalyzes the unwinding of RNA:DNA hybrid portion of the R-loops, promoting thus their resolution. The key importance of SETX in R-loops homeostasis and its relevance with pathophysiological events is highlighted by the evidence that gain or loss of function SETX mutations underlie the pathogenesis of two distinct neurological disorders. Here, we aim to describe the potential impact of SETX on tumor onset and progression, trying to emphasize how dysregulation of this enzyme observed in human tumors might impact tumorigenesis. To this aim, we will describe the functional relevance of SETX in regulating gene expression, genome integrity, and inflammation response and discuss how cancer-associated SETX mutations might affect these pathways, contributing thus to tumor development.
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Affiliation(s)
- Veronica Gatti
- National Research Council of Italy, Institute of Translational Pharmacology, Rome, Italy
| | - Sara De Domenico
- Department of Experimental Medicine, TOR, University of Rome Tor Vergata, Rome, Italy
| | - Gerry Melino
- Department of Experimental Medicine, TOR, University of Rome Tor Vergata, Rome, Italy
| | - Angelo Peschiaroli
- National Research Council of Italy, Institute of Translational Pharmacology, Rome, Italy.
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55
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Elsakrmy N, Cui H. R-Loops and R-Loop-Binding Proteins in Cancer Progression and Drug Resistance. Int J Mol Sci 2023; 24:ijms24087064. [PMID: 37108225 PMCID: PMC10138518 DOI: 10.3390/ijms24087064] [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: 02/26/2023] [Revised: 04/06/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
R-loops are three-stranded DNA/RNA hybrids that form by the annealing of the mRNA transcript to its coding template while displacing the non-coding strand. While R-loop formation regulates physiological genomic and mitochondrial transcription and DNA damage response, imbalanced R-loop formation can be a threat to the genomic integrity of the cell. As such, R-loop formation is a double-edged sword in cancer progression, and perturbed R-loop homeostasis is observed across various malignancies. Here, we discuss the interplay between R-loops and tumor suppressors and oncogenes, with a focus on BRCA1/2 and ATR. R-loop imbalances contribute to cancer propagation and the development of chemotherapy drug resistance. We explore how R-loop formation can cause cancer cell death in response to chemotherapeutics and be used to circumvent drug resistance. As R-loop formation is tightly linked to mRNA transcription, their formation is unavoidable in cancer cells and can thus be explored in novel cancer therapeutics.
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Affiliation(s)
- Noha Elsakrmy
- Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada
| | - Haissi Cui
- Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada
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56
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Vaklavas C, Stringer-Reasor EM, Elkhanany AM, Ryan KJ, Li Y, Theuer CP, Acosta EP, Wei S, Yang ES, Grizzle WE, Forero-Torres A. A phase I/II study of preoperative letrozole, everolimus, and carotuximab in stage 2 and 3 hormone receptor-positive and Her2-negative breast cancer. Breast Cancer Res Treat 2023; 198:217-229. [PMID: 36735117 PMCID: PMC10020303 DOI: 10.1007/s10549-023-06864-9] [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: 10/17/2022] [Accepted: 01/16/2023] [Indexed: 02/04/2023]
Abstract
PURPOSE In nonmetastatic hormone receptor-positive and Her2-negative breast cancer, preoperative endocrine therapies can yield outcomes similar with chemotherapy. We evaluated the tolerability and preliminary antitumor activity of preoperative letrozole, everolimus, and carotuximab, a monoclonal antibody targeting endoglin, in nonmetastatic breast cancer. METHODS Eligible patients had newly diagnosed, stage 2 or 3, hormone receptor-positive and Her2/neu-negative breast cancer. Patients received escalating doses of everolimus; the dose of letrozole and carotuximab were fixed at 2.5 mg PO daily and 15 mg/kg intravenously every 2 weeks, respectively. The primary objective was to determine the safety and tolerability of the combination. Secondary objectives included pharmacokinetic and pharmacodynamic studies and assessments of antitumor activity. RESULTS Fifteen patients enrolled. The recommended phase 2 dose of everolimus in combination with letrozole and carotuximab was 10 mg PO daily. The most frequent adverse events were headache (67%), fatigue (47%), facial flushing and swelling (47%), gingival hemorrhage (40%), epistaxis (33%), nausea and vomiting (27%). Headache constituted a dose-limiting toxicity. At least two signs of mucocutaneous telangiectasia developed in 92% of patients. Carotuximab accumulated in the extravascular space and accelerated the biodistribution and clearance of everolimus. All patients had residual disease. Gene expression analyses were consistent with downregulation of genes involved in proliferation and DNA repair. Among 6 patients with luminal B breast cancer, 5 converted to luminal A after one cycle of therapy. CONCLUSION Letrozole, everolimus, and carotuximab were tolerated in combination at their single-agent doses. Pharmacokinetic studies revealed an interaction between everolimus and carotuximab. TRIAL REGISTRATION This trial is registered with ClinicalTrials.gov (Identifier: NCT02520063), first posted on August 11, 2015, and is active, not recruiting.
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Affiliation(s)
- Christos Vaklavas
- Huntsman Cancer Institute of the University of Utah, 2000 Circle of Hope, RS2509, Salt Lake, UT, 84112, USA.
- University of Alabama at Birmingham, Birmingham, AL, USA.
| | | | | | - Kevin J Ryan
- University of Alabama at Birmingham, Birmingham, AL, USA
| | - Yufeng Li
- University of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | - Shi Wei
- University of Alabama at Birmingham, Birmingham, AL, USA
| | - Eddy S Yang
- University of Alabama at Birmingham, Birmingham, AL, USA
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57
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Marchena-Cruz E, Camino LP, Bhandari J, Silva S, Marqueta-Gracia JJ, Amdeen SA, Guillén-Mendoza C, García-Rubio ML, Calderón-Montaño JM, Xue X, Luna R, Aguilera A. DDX47, MeCP2, and other functionally heterogeneous factors protect cells from harmful R loops. Cell Rep 2023; 42:112148. [PMID: 36827184 PMCID: PMC10066596 DOI: 10.1016/j.celrep.2023.112148] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 12/20/2022] [Accepted: 02/06/2023] [Indexed: 02/25/2023] Open
Abstract
Unscheduled R loops can be a source of genome instability, a hallmark of cancer cells. Although targeted proteomic approaches and cellular analysis of specific mutants have uncovered factors potentially involved in R-loop homeostasis, we report a more open screening of factors whose depletion causes R loops based on the ability of activation-induced cytidine deaminase (AID) to target R loops. Immunofluorescence analysis of γH2AX caused by small interfering RNAs (siRNAs) covering 3,205 protein-coding genes identifies 59 potential candidates, from which 13 are analyzed further and show a significant increase of R loops. Such candidates are enriched in factors involved in chromatin, transcription, and RNA biogenesis and other processes. A more focused study shows that the DDX47 helicase is an R-loop resolvase, whereas the MeCP2 methyl-CpG-binding protein uncovers a link between DNA methylation and R loops. Thus, our results suggest that a plethora of gene dysfunctions can alter cell physiology via affecting R-loop homeostasis by different mechanisms.
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Affiliation(s)
- Esther Marchena-Cruz
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain
| | - Lola P Camino
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain
| | - Jay Bhandari
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | - Sónia Silva
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain
| | - José Javier Marqueta-Gracia
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain; Departmento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Shahad A Amdeen
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | - Cristina Guillén-Mendoza
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain; Departmento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - María L García-Rubio
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain; Departmento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - José M Calderón-Montaño
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain
| | - Xiaoyu Xue
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | - Rosa Luna
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain; Departmento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain.
| | - Andrés Aguilera
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092 Seville, Spain; Departmento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain.
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Lee SY, Miller KM, Kim JJ. Clinical and Mechanistic Implications of R-Loops in Human Leukemias. Int J Mol Sci 2023; 24:ijms24065966. [PMID: 36983041 PMCID: PMC10052022 DOI: 10.3390/ijms24065966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 03/17/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Genetic mutations or environmental agents are major contributors to leukemia and are associated with genomic instability. R-loops are three-stranded nucleic acid structures consisting of an RNA-DNA hybrid and a non-template single-stranded DNA. These structures regulate various cellular processes, including transcription, replication, and DSB repair. However, unregulated R-loop formation can cause DNA damage and genomic instability, which are potential drivers of cancer including leukemia. In this review, we discuss the current understanding of aberrant R-loop formation and how it influences genomic instability and leukemia development. We also consider the possibility of R-loops as therapeutic targets for cancer treatment.
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Affiliation(s)
- Seo-Yun Lee
- Department of Life Science and Multidisciplinary, Genome Institute, Hallym University, Chuncheon 24252, Republic of Korea
| | - Kyle M Miller
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Jae-Jin Kim
- Department of Life Science and Multidisciplinary, Genome Institute, Hallym University, Chuncheon 24252, Republic of Korea
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Ling M, Tang C, Yang X, Yu N, Song Y, Ding W, Sun Y, Yan R, Wang S, Li X, Gao H, Zhang Z, Xing Y. Integrated metabolomics and phosphoproteomics reveal the protective role of exosomes from human umbilical cord mesenchymal stem cells in naturally aging mouse livers. Exp Cell Res 2023; 427:113566. [PMID: 37004949 DOI: 10.1016/j.yexcr.2023.113566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/13/2023] [Accepted: 03/18/2023] [Indexed: 04/03/2023]
Abstract
BACKGROUND Aging is characterized by a general decline in cellular function, which ultimately affects whole body homeostasis. This study aimed to investigate the effects and underlying mechanisms of exosomes derived from human umbilical cord mesenchymal stem cells (hUCMSC-exos) on the livers of naturally aging mice. METHOD Twenty-two-month-old C57BL6 mice were used as a natural aging animal model, divided into a saline-treated wild-type aged control group (WT-AC) and a hUCMSC-exo-treated group (WT-AEX), and then detected by morphology, metabolomics and phosphoproteomics. RESULTS Morphological analysis showed that hUCMSC-exos ameliorated structural disorder and decreased markers of senescence and genome instability in aging livers. Metabolomics showed that hUCMSC-exos decreased the contents of saturated glycerophospholipids, palmitoyl-glycerols and eicosanoid derivatives associated with lipotoxicity and inflammation, consistent with the decreased phosphorylation of metabolic enzymes, such as propionate-CoA ligase (Acss2), at S267 detected by phosphoproteomics. Moreover, phosphoproteomics indicated that hUCMSC-exos reduced the phosphorylation of proteins participating in nuclear transport and cancer signaling, such as heat shock protein HSP90-beta (Hsp90ab1) at S226 and nucleoprotein TPR (Tpr) at S453 and S379, while increasing those involved in intracellular communication, such as calnexin (Canx) at S563 and PDZ domain-containing protein 8 (Pdzd8). Finally, phosphorylated HSP90β and Tpr were verified predominantly in hepatocytes. CONCLUSION HUCMSC-exos improved metabolic reprogramming and genome stability mainly associated with phosphorylated HSP90β in hepatocytes in natural aging livers. This work provides a comprehensive resource of biological data by omics to support future investigations of hUCMSC-exos in aging.
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Affiliation(s)
- Mingying Ling
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Congmin Tang
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Xuechun Yang
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Na Yu
- Shandong Precision Medicine Engineering Laboratory of Bacterial Anti-tumor Drugs, 250101, Jinan, Shandong, China; College of Clinical Medicine, Shandong University, 250012, Jinan, Shandong, China
| | - Yiping Song
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Wenjing Ding
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Yan Sun
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Rong Yan
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Shaopeng Wang
- Shandong Precision Medicine Engineering Laboratory of Bacterial Anti-tumor Drugs, 250101, Jinan, Shandong, China
| | - Xuehui Li
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Haiqing Gao
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Zhen Zhang
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China
| | - Yanqiu Xing
- Department of Geriatric Medicine, Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, 250012, Jinan, Shandong, China.
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Saha S, Pommier Y. R-loops, type I topoisomerases and cancer. NAR Cancer 2023; 5:zcad013. [PMID: 37600974 PMCID: PMC9984992 DOI: 10.1093/narcan/zcad013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/18/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
R-loops are abundant and dynamic structures ubiquitously present in human cells both in the nuclear and mitochondrial genomes. They form in cis in the wake of transcription complexes and in trans apart from transcription complexes. In this review, we focus on the relationship between R-loops and topoisomerases, and cancer genomics and therapies. We summarize the topological parameters associated with the formation and resolution of R-loops, which absorb and release high levels of genomic negative supercoiling (Sc-). We review the deleterious consequences of excessive R-loops and rationalize how human type IA (TOP3B) and type IB (TOP1) topoisomerases regulate and resolve R-loops in coordination with helicase and RNase H enzymes. We also review the drugs (topoisomerase inhibitors, splicing inhibitors, G4 stabilizing ligands) and cancer predisposing genes (BRCA1/2, transcription, and splicing genes) known to induce R-loops, and whether stabilizing R-loops and thereby inducing genomic damage can be viewed as a strategy for cancer treatment.
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Affiliation(s)
- Sourav Saha
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Yves Pommier
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
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61
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Zhao Y, Simon M, Seluanov A, Gorbunova V. DNA damage and repair in age-related inflammation. Nat Rev Immunol 2023; 23:75-89. [PMID: 35831609 PMCID: PMC10106081 DOI: 10.1038/s41577-022-00751-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/07/2022] [Indexed: 02/07/2023]
Abstract
Genomic instability is an important driver of ageing. The accumulation of DNA damage is believed to contribute to ageing by inducing cell death, senescence and tissue dysfunction. However, emerging evidence shows that inflammation is another major consequence of DNA damage. Inflammation is a hallmark of ageing and the driver of multiple age-related diseases. Here, we review the evidence linking DNA damage, inflammation and ageing, highlighting how premature ageing syndromes are associated with inflammation. We discuss the mechanisms by which DNA damage induces inflammation, such as through activation of the cGAS-STING axis and NF-κB activation by ATM. The triggers for activation of these signalling cascades are the age-related accumulation of DNA damage, activation of transposons, cellular senescence and the accumulation of persistent R-loops. We also discuss how epigenetic changes triggered by DNA damage can lead to inflammation and ageing via redistribution of heterochromatin factors. Finally, we discuss potential interventions against age-related inflammation.
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Affiliation(s)
- Yang Zhao
- Department of Biology, University of Rochester, Rochester, NY, USA.,Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China.,Department of Hepatobiliary and Pancreatic Surgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Matthew Simon
- Department of Biology, University of Rochester, Rochester, NY, USA
| | - Andrei Seluanov
- Department of Biology, University of Rochester, Rochester, NY, USA. .,Department of Medicine, University of Rochester, Rochester, NY, USA.
| | - Vera Gorbunova
- Department of Biology, University of Rochester, Rochester, NY, USA. .,Department of Medicine, University of Rochester, Rochester, NY, USA.
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62
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Stopar A, Nicholson AW. Multivalent forms of the ribonuclease H1 hybrid binding domain are high-affinity binders of RNA-DNA hybrids. FEBS Lett 2023; 597:472-482. [PMID: 36443824 DOI: 10.1002/1873-3468.14541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 10/18/2022] [Accepted: 10/22/2022] [Indexed: 11/30/2022]
Abstract
The hybrid binding domain (HBD) is a conserved fold present in ribonucleases H1 that selectively recognizes RNA-DNA hybrids, which are structures present in cellular R-loops and participate in diverse biological processes. We engineered multivalent HBD proteins to create high-affinity hybrid binders. Using EMSA- and SPR-based analyses, we showed that the triple-HBD protein exhibits a ~ 22 000-fold increase in hybrid affinity (KD 370 pm) relative to the single HBD (KD 8.29 μm), with the length and sequence of the linkers enabling optimal function. These findings provide a framework for testing models that correlate multivalency and affinity to understand how multivalent proteins function and also can serve to guide applications that exploit multivalency as a strategy to enhance binding affinity.
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Affiliation(s)
- Alex Stopar
- Department of Biology, Temple University, Philadelphia, PA, USA
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63
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Debbabi I, Vacher S, Neuzillet C, Cros J, Revillon F, Petitalot A, Turpin A, Antonio S, Girard E, Dupain C, Kamal M, Hammel P, Bièche I, Masliah-Planchon J, Caputo SM. Identification of a large intra-exonic deletion in BRCA2 exon 18 in a pancreatic ductal adenocarcinoma. Ther Adv Med Oncol 2023; 15:17588359221146132. [PMID: 36700131 PMCID: PMC9869184 DOI: 10.1177/17588359221146132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 11/30/2022] [Indexed: 01/19/2023] Open
Abstract
By 2030, pancreatic cancer will become the second leading cause of cancer-related deaths in the United States and in Europe. The management of patients with advanced pancreatic cancer relies on chemotherapy and poly (ADP-ribose) polymerase inhibitors for patients who carry BRCA1/2 inactivating alterations. Some variants, such as large insertion/deletions (Indels), inactivating BRCA1/2 and therefore of clinical relevance can be hard to detect by next-generation sequencing techniques. Here we report a 47-year-old patient presenting with pancreatic cancer whose tumour harbours a large somatic intra-exonic deletion of BRCA2 of 141 bp. This BRCA2 deletion, located in the C-terminal domain, can be considered as pathogenic and consequently affect tumorigenesis because it is involved in the interaction between the DSS1 protein and DNA. Thanks to the optimized bioinformatics algorithm, this intermediate size deletion in BRCA2 was identified, enabling personalized patient management via the inclusion of the patients in a clinical trial.
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Affiliation(s)
- Inès Debbabi
- Department of Genetics, Institut Curie, Paris, France
| | - Sophie Vacher
- Department of Genetics, Institut Curie, Paris, France,PSL Research University, Paris, France
| | - Cindy Neuzillet
- Department of Medical Oncology, Curie Institute, Versailles Saint Quentin University, Paris, France
| | - Jérome Cros
- INSERM UMR1149, Beaujon University Hospital, Paris University, Paris, France,Department of Pathology, Beaujon University, Hospital Paris 7 Diderot University, Paris, France
| | | | - Ambre Petitalot
- Department of Genetics, Institut Curie, Paris, France,PSL Research University, Paris, France
| | - Anthony Turpin
- ULR9020-UMR-S 1277 Canther-Cancer Heterogeneity, Plasticity and Resistance to Therapies, University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, France,Medical Oncology Department, CHU Lille, University of Lille, France
| | - Samantha Antonio
- Department of Genetics, Institut Curie, Paris, France,PSL Research University, Paris, France
| | | | - Célia Dupain
- Department of Drug Development and Innovation, Institut Curie, PSL Research University, Paris
| | - Maud Kamal
- Department of Drug Development and Innovation, Institut Curie, PSL Research University, Paris
| | - Pascal Hammel
- Department of Digestive and Medical Oncology, Paris-Saclay University, Hôpital Paul Brousse, Villejuif, France
| | - Ivan Bièche
- Department of Genetics, Institut Curie, Paris, France,Université de Paris, Paris, France
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64
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Emerging role for R-loop formation in hepatocellular carcinoma. Genes Genomics 2023; 45:543-551. [PMID: 36635460 DOI: 10.1007/s13258-022-01360-8] [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: 09/23/2022] [Accepted: 12/20/2022] [Indexed: 01/13/2023]
Abstract
The pathophysiological characteristics of hepatocellular carcinoma (HCC) is closely associated with genomic instability. Genomic instability has long been considered to be a hallmark of both human genetic disease and cancers. It is now well accepted that regulating R-loop formation to minimized levels is one of critical modulation to maintain genome integrity, and that improper regulation of R-loop metabolism causes genomic instability via DNA breakage, ultimately resulting in replicative senescence and even tumorigenesis. Given that R-loop is natural by-product formed during normal transcription condition, and that several types of cancer have defense mechanism against the genomic instability resulted from R-loop formation, modulating functional implication of proteins involved in the intrinsic and specific mechanisms of abnormal R-loop formation in cancers therefore could play an important part in appropriated therapeutic strategies for HCC cohorts. In this review, we highlight the latest understanding on how R-loops promote genomic instability and address how alterations in these pathways link to human HCC.
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65
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Gospodinov A, Dzhokova S, Petrova M, Ugrinova I. Chromatin regulators in DNA replication and genome stability maintenance during S-phase. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 135:243-280. [PMID: 37061334 DOI: 10.1016/bs.apcsb.2023.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
The duplication of genetic information is central to life. The replication of genetic information is strictly controlled to ensure that each piece of genomic DNA is copied only once during a cell cycle. Factors that slow or stop replication forks cause replication stress. Replication stress is a major source of genome instability in cancer cells. Multiple control mechanisms facilitate the unimpeded fork progression, prevent fork collapse and coordinate fork repair. Chromatin alterations, caused by histone post-translational modifications and chromatin remodeling, have critical roles in normal replication and in avoiding replication stress and its consequences. This text reviews the chromatin regulators that ensure DNA replication and the proper response to replication stress. We also briefly touch on exploiting replication stress in therapeutic strategies. As chromatin regulators are frequently mutated in cancer, manipulating their activity could provide many possibilities for personalized treatment.
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Affiliation(s)
- Anastas Gospodinov
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
| | - Stefka Dzhokova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Maria Petrova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Iva Ugrinova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
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66
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Sarker AH, Cooper PK. Slot Blot Assay for Detection of R Loops. Methods Mol Biol 2023; 2701:149-156. [PMID: 37574480 DOI: 10.1007/978-1-0716-3373-1_9] [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] [Indexed: 08/15/2023]
Abstract
R loops (DNA-RNA hybrid) are three-stranded nucleic acid structures that comprise of template DNA strand hybridized with the nascent RNA leaving the displaced non-template strand. Although a programmed R loop formation can serve as powerful regulators of gene expression, these structures can also turn into major sources of genomic instability and contribute to the development of diseases. Therefore, understanding how cells prevent the deleterious consequences of R loops yet allow R loop formation to participate in various physiological processes will help to understand how their homeostasis is maintained. Detection and quantitative measurements of R loops are critical that largely relied on S9.6 antibody. Immunofluorescence methods are frequently used to localize and quantify R loops in the cell but they require specialized tools for analysis and relatively expensive; therefore, they are not always useful for initial assessments of R loop accumulation. Here, we describe an improved slot blot protocol to detect and estimate R loops and show its sensitivity and specificity using the S9.6 antibody. Since specific factors protecting cells from harmful R loop accumulation are expanding, this protocol can be used to determine R loop accumulation in research and clinical settings.
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Affiliation(s)
- Altaf H Sarker
- Department of BioEngineering and BioMedical Sciences, Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
| | - Priscilla K Cooper
- Department of BioEngineering and BioMedical Sciences, Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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67
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RAD18 opposes transcription-associated genome instability through FANCD2 recruitment. PLoS Genet 2022; 18:e1010309. [DOI: 10.1371/journal.pgen.1010309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 12/20/2022] [Accepted: 11/22/2022] [Indexed: 12/13/2022] Open
Abstract
DNA replication is a vulnerable time for genome stability maintenance. Intrinsic stressors, as well as oncogenic stress, can challenge replication by fostering conflicts with transcription and stabilizing DNA:RNA hybrids. RAD18 is an E3 ubiquitin ligase for PCNA that is involved in coordinating DNA damage tolerance pathways to preserve genome stability during replication. In this study, we show that RAD18 deficient cells have higher levels of transcription-replication conflicts and accumulate DNA:RNA hybrids that induce DNA double strand breaks and replication stress. We find that these effects are driven in part by failure to recruit the Fanconi Anemia protein FANCD2 at difficult to replicate and R-loop prone genomic sites. FANCD2 activation caused by splicing inhibition or aphidicolin treatment is critically dependent on RAD18 activity. Thus, we highlight a RAD18-dependent pathway promoting FANCD2-mediated suppression of R-loops and transcription-replication conflicts.
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68
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Wu T, Lyu R, He C. spKAS-seq reveals R-loop dynamics using low-input materials by detecting single-stranded DNA with strand specificity. SCIENCE ADVANCES 2022; 8:eabq2166. [PMID: 36449625 PMCID: PMC9710868 DOI: 10.1126/sciadv.abq2166] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 10/13/2022] [Indexed: 05/26/2023]
Abstract
R-loops affect transcription and genome stability. Dysregulation of R-loops is related to human diseases. Genome-wide R-loop mapping typically uses the S9.6 antibody or inactive ribonuclease H, both requiring a large number of cells with varying results observed depending on the approach applied. Here, we present strand-specific kethoxal-assisted single-stranded DNA (ssDNA) sequencing (spKAS-seq) to map R-loops by taking advantage of the presence of a ssDNA in the triplex structure. We show that spKAS-seq detects R-loops and their dynamics at coding sequences, enhancers, and other intergenic regions with as few as 50,000 cells. A joint analysis of R-loops and chromatin-bound RNA binding proteins (RBPs) suggested that R-loops can be RBP binding hotspots on the chromatin.
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Affiliation(s)
- Tong Wu
- Department of Chemistry, University of Chicago, Chicago, IL, USA
- Howard Hughes Medical Institute, University of Chicago, Chicago, IL, USA
| | - Ruitu Lyu
- Department of Chemistry, University of Chicago, Chicago, IL, USA
- Howard Hughes Medical Institute, University of Chicago, Chicago, IL, USA
| | - Chuan He
- Department of Chemistry, University of Chicago, Chicago, IL, USA
- Howard Hughes Medical Institute, University of Chicago, Chicago, IL, USA
- Department of Biochemistry and Molecular Biology, Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
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69
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Li X, Wang L, Liu X, Zheng Z, Kong D. Cellular regulation and stability of DNA replication forks in eukaryotic cells. DNA Repair (Amst) 2022; 120:103418. [DOI: 10.1016/j.dnarep.2022.103418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 10/03/2022] [Accepted: 10/07/2022] [Indexed: 11/03/2022]
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70
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Khan ES, Danckwardt S. Pathophysiological Role and Diagnostic Potential of R-Loops in Cancer and Beyond. Genes (Basel) 2022; 13:genes13122181. [PMID: 36553448 PMCID: PMC9777984 DOI: 10.3390/genes13122181] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/07/2022] [Accepted: 11/14/2022] [Indexed: 11/24/2022] Open
Abstract
R-loops are DNA-RNA hybrids that play multifunctional roles in gene regulation, including replication, transcription, transcription-replication collision, epigenetics, and preserving the integrity of the genome. The aberrant formation and accumulation of unscheduled R-loops can disrupt gene expression and damage DNA, thereby causing genome instability. Recent links between unscheduled R-loop accumulation and the abundance of proteins that modulate R-loop biogenesis have been associated with numerous human diseases, including various cancers. Although R-loops are not necessarily causative for all disease entities described to date, they can perpetuate and even exacerbate the initially disease-eliciting pathophysiology, making them structures of interest for molecular diagnostics. In this review, we discuss the (patho) physiological role of R-loops in health and disease, their surprising diagnostic potential, and state-of-the-art techniques for their detection.
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Affiliation(s)
- Essak S. Khan
- Posttranscriptional Gene Regulation, Cancer Research and Experimental Hemostasis, University Medical Center Mainz, 55131 Mainz, Germany
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
- German Consortium for Translational Cancer Research (DKTK), DKFZ Frankfurt-Mainz, 60590 Frankfurt am Main, Germany
| | - Sven Danckwardt
- Posttranscriptional Gene Regulation, Cancer Research and Experimental Hemostasis, University Medical Center Mainz, 55131 Mainz, Germany
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
- German Center for Cardiovascular Research (DZHK), Rhine-Main, 55131 Mainz, Germany
- Correspondence:
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71
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Dator RP, Murray KJ, Luedtke MW, Jacobs FC, Kassie F, Nguyen HD, Villalta PW, Balbo S. Identification of Formaldehyde-Induced DNA-RNA Cross-Links in the A/J Mouse Lung Tumorigenesis Model. Chem Res Toxicol 2022; 35:2025-2036. [PMID: 36356054 PMCID: PMC10336729 DOI: 10.1021/acs.chemrestox.2c00206] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent lung carcinogen present in tobacco products, and exposure to it is likely one of the factors contributing to the development of lung cancer in cigarette smokers. To exert its carcinogenic effects, NNK must be metabolically activated into highly reactive species generating a wide spectrum of DNA damage. We have identified a new class of DNA adducts, DNA-RNA cross-links found for the first time in NNK-treated mice lung DNA using our improved high-resolution accurate mass segmented full scan data-dependent neutral loss MS3 screening strategy. The levels of these DNA-RNA cross-links were found to be significantly higher in NNK-treated mice compared to the corresponding controls, which is consistent with higher levels of formaldehyde due to NNK metabolism as compared to endogenous levels. We hypothesize that this DNA-RNA cross-linking occurs through reaction with NNK-generated formaldehyde and speculate that this phenomenon has broad implications for NNK-induced carcinogenesis. The structures of these cross-links were characterized using high-resolution LC-MS2 and LC-MS3 accurate mass spectral analysis and comparison to a newly synthesized standard. Taken together, our data demonstrate a previously unknown link between DNA-RNA cross-link adducts and NNK and provide a unique opportunity to further investigate how these novel NNK-derived DNA-RNA cross-links contribute to carcinogenesis in the future.
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Affiliation(s)
- Romel P. Dator
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - Kevin J. Murray
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St. Paul, MN 55108
- Center for Mass Spectrometry and Proteomics, University of Minnesota, St. Paul, MN 55108
| | | | - Foster C. Jacobs
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Division of Environmental Health Sciences, School of Public Health, University of Minnesota, Minneapolis, MN 55455
| | - Fekadu Kassie
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108
| | - Hai Dang Nguyen
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Department of Pharmacology, College of Medicine, University of Minnesota, Minneapolis, MN 55455
| | - Peter W. Villalta
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455
| | - Silvia Balbo
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Division of Environmental Health Sciences, School of Public Health, University of Minnesota, Minneapolis, MN 55455
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72
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Gritti I, Basso V, Rinchai D, Corigliano F, Pivetti S, Gaviraghi M, Rosano D, Mazza D, Barozzi S, Roncador M, Parmigiani G, Legube G, Parazzoli D, Cittaro D, Bedognetti D, Mondino A, Segalla S, Tonon G. Loss of ribonuclease DIS3 hampers genome integrity in myeloma by disrupting DNA:RNA hybrid metabolism. EMBO J 2022; 41:e108040. [PMID: 36215697 PMCID: PMC9670201 DOI: 10.15252/embj.2021108040] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 07/25/2022] [Accepted: 09/23/2022] [Indexed: 01/13/2023] Open
Abstract
The ribonuclease DIS3 is one of the most frequently mutated genes in the hematological cancer multiple myeloma, yet the basis of its tumor suppressor function in this disease remains unclear. Herein, exploiting the TCGA dataset, we found that DIS3 plays a prominent role in the DNA damage response. DIS3 inactivation causes genomic instability by increasing mutational load, and a pervasive accumulation of DNA:RNA hybrids that induces genomic DNA double-strand breaks (DSBs). DNA:RNA hybrid accumulation also prevents binding of the homologous recombination (HR) machinery to double-strand breaks, hampering DSB repair. DIS3-inactivated cells become sensitive to PARP inhibitors, suggestive of a defect in homologous recombination repair. Accordingly, multiple myeloma patient cells mutated for DIS3 harbor an increased mutational burden and a pervasive overexpression of pro-inflammatory interferon, correlating with the accumulation of DNA:RNA hybrids. We propose DIS3 loss in myeloma to be a driving force for tumorigenesis via DNA:RNA hybrid-dependent enhanced genome instability and increased mutational rate. At the same time, DIS3 loss represents a liability that might be therapeutically exploited in patients whose cancer cells harbor DIS3 mutations.
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Affiliation(s)
- Ilaria Gritti
- Functional Genomics of Cancer Unit, Division of Experimental OncologyIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Veronica Basso
- Division of Immunology, Transplantation and Infectious DiseaseIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | | | - Federica Corigliano
- Functional Genomics of Cancer Unit, Division of Experimental OncologyIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Silvia Pivetti
- Functional Genomics of Cancer Unit, Division of Experimental OncologyIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Marco Gaviraghi
- Functional Genomics of Cancer Unit, Division of Experimental OncologyIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Dalia Rosano
- Functional Genomics of Cancer Unit, Division of Experimental OncologyIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Davide Mazza
- Experimental Imaging CenterIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Sara Barozzi
- IFOM, The FIRC Institute of Molecular OncologyMilanoItaly
| | - Marco Roncador
- Department of Data SciencesDana Farber Cancer InstituteBostonMAUSA,Department of BiostatisticsHarvard T.H. Chan School of Public HealthBostonMAUSA
| | - Giovanni Parmigiani
- Department of Data SciencesDana Farber Cancer InstituteBostonMAUSA,Department of BiostatisticsHarvard T.H. Chan School of Public HealthBostonMAUSA
| | - Gaelle Legube
- MCD, Centre de Biologie Intégrative (CBI), CNRSUniversity of ToulouseToulouseFrance
| | | | - Davide Cittaro
- Center for Omics Sciences @OSR (COSR)Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Davide Bedognetti
- Cancer Research DepartmentSidra MedicineDohaQatar,Dipartimento di Medicina Interna e Specialità MedicheUniversità degli Studi di GenovaGenoaItaly
| | - Anna Mondino
- Division of Immunology, Transplantation and Infectious DiseaseIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Simona Segalla
- Functional Genomics of Cancer Unit, Division of Experimental OncologyIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly
| | - Giovanni Tonon
- Functional Genomics of Cancer Unit, Division of Experimental OncologyIstituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly,Center for Omics Sciences @OSR (COSR)Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific InstituteMilanoItaly,Università Vita‐Salute San RaffaeleMilanItaly
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73
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Thada V, Greenberg RA. Unpaved roads: How the DNA damage response navigates endogenous genotoxins. DNA Repair (Amst) 2022; 118:103383. [PMID: 35939975 PMCID: PMC9703833 DOI: 10.1016/j.dnarep.2022.103383] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 07/28/2022] [Accepted: 07/28/2022] [Indexed: 02/03/2023]
Abstract
Accurate DNA repair is essential for cellular and organismal homeostasis, and DNA repair defects result in genetic diseases and cancer predisposition. Several environmental factors, such as ultraviolet light, damage DNA, but many other molecules with DNA damaging potential are byproducts of normal cellular processes. In this review, we highlight some of the prominent sources of endogenous DNA damage as well as their mechanisms of repair, with a special focus on repair by the homologous recombination and Fanconi anemia pathways. We also discuss how modulating DNA damage caused by endogenous factors may augment current approaches used to treat BRCA-deficient cancers. Finally, we describe how synthetic lethal interactions may be exploited to exacerbate DNA repair deficiencies and cause selective toxicity in additional types of cancers.
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74
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Chen L, Wang Y, Lin J, Song Z, Wang Q, Zhao W, Wang Y, Xiu X, Deng Y, Li X, Li Q, Wang X, Li J, Liu X, Liu K, Zhou J, Li K, Liu Y, Liao S, Deng Q, Xu C, Sun Q, Wu S, Zhang K, Guan MX, Zhou T, Sun F, Cai X, Huang C, Shan G. Exportin 4 depletion leads to nuclear accumulation of a subset of circular RNAs. Nat Commun 2022; 13:5769. [PMID: 36182935 PMCID: PMC9526749 DOI: 10.1038/s41467-022-33356-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 09/09/2022] [Indexed: 12/19/2022] Open
Abstract
Numerous RNAs are exported from the nucleus, abnormalities of which lead to cellular complications and diseases. How thousands of circular RNAs (circRNAs) are exported from the nucleus remains elusive. Here, we provide lines of evidence to demonstrate a link between the conserved Exportin 4 (XPO4) and nuclear export of a subset of circRNAs in metazoans. Exonic circRNAs (ecircRNAs) with higher expression levels, larger length, and lower GC content are more sensitive to XPO4 deficiency. Cellular insufficiency of XPO4 leads to nuclear circRNA accumulation, circRNA:DNA (ciR-loop) formation, linear RNA:DNA (liR-loop) buildup, and DNA damage. DDX39 known to modulate circRNA export can resolve ciR-loop, and splicing factors involved in the biogenesis of circRNAs can also affect the levels of ciR-loop. Testis and brain are two organs with high abundance of circRNAs, and insufficient XPO4 levels are detrimental, as Xpo4 heterozygous mice display male infertility and neural phenotypes. Increased levels of ciR-loop, R-loop, and DNA damage along with decreased cell numbers are observed in testis and hippocampus of Xpo4 heterozygotes. This study sheds light on the understandings of mechanism of circRNA export and reveals the significance of efficient nuclear export of circRNAs in cellular physiology. This study identifies the evolutionarily conserved Exportin 4 as an essential regulator in the nuclear export of circRNAs. Defective circRNA export results in R-loop formation and DNA damage in cells, as well as testis and neurological defects in mice.
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Affiliation(s)
- Liang Chen
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Yucong Wang
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Jiamei Lin
- School of Life Sciences, Chongqing University, Chongqing, 401331, China.,Center of Plant Functional Genomics, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, 401331, China
| | - Zhenxing Song
- School of Life Sciences, Chongqing University, Chongqing, 401331, China.,Center of Plant Functional Genomics, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, 401331, China
| | - Qinwei Wang
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Wenfang Zhao
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Yan Wang
- School of Optometry and Ophthalmology and the Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325003, China.,State Key Laboratory of Optometry, Ophthalmology, and Visual Science, 270 Xueyuan Road, Wenzhou, Zhejiang, 325003, China
| | - Xiaoyu Xiu
- School of Optometry and Ophthalmology and the Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325003, China.,State Key Laboratory of Optometry, Ophthalmology, and Visual Science, 270 Xueyuan Road, Wenzhou, Zhejiang, 325003, China
| | - Yuqi Deng
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Xiuzhi Li
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Qiqi Li
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Xiaolin Wang
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Jingxin Li
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Xu Liu
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Kunpeng Liu
- Center for Plant Biology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jincong Zhou
- Center for Plant Biology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Kuan Li
- Center for Plant Biology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yuchan Liu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Shanhui Liao
- Division of Life Science and Medicine, CAS Key Laboratory of Structural Biology, University of Science and Technology of China, Hefei, 230027, China
| | - Qin Deng
- Analytical and Testing Center, Chongqing University, Chongqing, 400030, China
| | - Chao Xu
- Division of Life Science and Medicine, CAS Key Laboratory of Structural Biology, University of Science and Technology of China, Hefei, 230027, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Shengzhou Wu
- School of Optometry and Ophthalmology and the Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325003, China.,State Key Laboratory of Optometry, Ophthalmology, and Visual Science, 270 Xueyuan Road, Wenzhou, Zhejiang, 325003, China
| | - Kaiming Zhang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Min-Xin Guan
- The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Zhejiang Provincial Key Lab of Genetic and Developmental Disorder, Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, 310016, China
| | - Tianhua Zhou
- Department of Cell Biology and Department of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Cancer Center, Institute of Gastroenterology, Zhejiang University, Hangzhou, 310016, China
| | - Fei Sun
- Sir Run-Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310016, China
| | - Xiujun Cai
- Sir Run-Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310016, China
| | - Chuan Huang
- School of Life Sciences, Chongqing University, Chongqing, 401331, China. .,Center of Plant Functional Genomics, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, 401331, China.
| | - Ge Shan
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China. .,Department of Pulmonary and Critical Care Medicine, Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China.
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75
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Tingey M, Schnell SJ, Yu W, Saredy J, Junod S, Patel D, Alkurdi AA, Yang W. Technologies Enabling Single-Molecule Super-Resolution Imaging of mRNA. Cells 2022; 11:3079. [PMID: 36231040 PMCID: PMC9564294 DOI: 10.3390/cells11193079] [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: 08/13/2022] [Revised: 09/22/2022] [Accepted: 09/28/2022] [Indexed: 11/16/2022] Open
Abstract
The transient nature of RNA has rendered it one of the more difficult biological targets for imaging. This difficulty stems both from the physical properties of RNA as well as the temporal constraints associated therewith. These concerns are further complicated by the difficulty in imaging endogenous RNA within a cell that has been transfected with a target sequence. These concerns, combined with traditional concerns associated with super-resolution light microscopy has made the imaging of this critical target difficult. Recent advances have provided researchers the tools to image endogenous RNA in live cells at both the cellular and single-molecule level. Here, we review techniques used for labeling and imaging RNA with special emphases on various labeling methods and a virtual 3D super-resolution imaging technique.
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Affiliation(s)
| | | | | | | | | | | | | | - Weidong Yang
- Department of Biology, Temple University, Philadelphia, PA 19122, USA
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76
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Sarni D, Barroso S, Shtrikman A, Irony-Tur Sinai M, Oren YS, Aguilera A, Kerem B. Topoisomerase 1-dependent R-loop deficiency drives accelerated replication and genomic instability. Cell Rep 2022; 40:111397. [PMID: 36170822 PMCID: PMC9532845 DOI: 10.1016/j.celrep.2022.111397] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 06/26/2022] [Accepted: 08/31/2022] [Indexed: 11/29/2022] Open
Abstract
DNA replication is a complex process tightly regulated to ensure faithful genome duplication, and its perturbation leads to DNA damage and genomic instability. Replication stress is commonly associated with slow and stalled replication forks. Recently, accelerated replication has emerged as a non-canonical form of replication stress. However, the molecular basis underlying fork acceleration is largely unknown. Here, we show that mutated HRAS activation leads to increased topoisomerase 1 (TOP1) expression, causing aberrant replication fork acceleration and DNA damage by decreasing RNA-DNA hybrids or R-loops. In these cells, restoration of TOP1 expression or mild replication inhibition rescues the perturbed replication and reduces DNA damage. Furthermore, TOP1 or RNaseH1 overexpression induces accelerated replication and DNA damage, highlighting the importance of TOP1 equilibrium in regulating R-loop homeostasis to ensure faithful DNA replication and genome integrity. Altogether, our results dissect a mechanism of oncogene-induced DNA damage by aberrant replication fork acceleration. Increased TOP1 expression by mutated RAS reduces R loops Low R-loop levels promote accelerated replication and DNA damage TOP1 restoration or mild replication inhibition rescue DNA acceleration and damage High TOP1 expression is associated with replication mutagenesis in cancer
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Affiliation(s)
- Dan Sarni
- Department of Genetics, The Life Sciences Institute, The Hebrew University, Jerusalem 91904, Israel
| | - Sonia Barroso
- Department of Genome Biology, Andalusian Center of Molecular Biology and Regenerative Medicine CABIMER, Seville Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | - Alon Shtrikman
- Department of Genetics, The Life Sciences Institute, The Hebrew University, Jerusalem 91904, Israel
| | - Michal Irony-Tur Sinai
- Department of Genetics, The Life Sciences Institute, The Hebrew University, Jerusalem 91904, Israel
| | - Yifat S Oren
- Department of Genetics, The Life Sciences Institute, The Hebrew University, Jerusalem 91904, Israel
| | - Andrés Aguilera
- Department of Genome Biology, Andalusian Center of Molecular Biology and Regenerative Medicine CABIMER, Seville Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | - Batsheva Kerem
- Department of Genetics, The Life Sciences Institute, The Hebrew University, Jerusalem 91904, Israel.
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77
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Miglietta G, Marinello J, Russo M, Capranico G. Ligands stimulating antitumour immunity as the next G-quadruplex challenge. Mol Cancer 2022; 21:180. [PMID: 36114513 PMCID: PMC9482198 DOI: 10.1186/s12943-022-01649-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/22/2022] [Indexed: 11/10/2022] Open
Abstract
AbstractG-quadruplex (G4) binders have been investigated to discover new anticancer drugs worldwide in past decades. As these ligands are generally not highly cytotoxic, the discovery rational was mainly based on increasing the cell-killing potency. Nevertheless, no G4 binder has been shown yet to be effective in cancer patients. Here, G4 binder activity at low dosages will be discussed as a critical feature to discover ligands with therapeutic effects in cancer patients. Specific effects of G4 binders al low doses have been reported to occur in cancer and normal cells. Among them, genome instability and the stimulation of cytoplasmic processes related to autophagy and innate immune response open to the use of G4 binders as immune-stimulating agents. Thus, we propose a new rational of drug discovery, which is not based on cytotoxic potency but rather on immune gene activation at non-cytotoxic dosage.
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78
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Groelly FJ, Dagg RA, Petropoulos M, Rossetti GG, Prasad B, Panagopoulos A, Paulsen T, Karamichali A, Jones SE, Ochs F, Dionellis VS, Puig Lombardi E, Miossec MJ, Lockstone H, Legube G, Blackford AN, Altmeyer M, Halazonetis TD, Tarsounas M. Mitotic DNA synthesis is caused by transcription-replication conflicts in BRCA2-deficient cells. Mol Cell 2022; 82:3382-3397.e7. [PMID: 36002001 PMCID: PMC9631240 DOI: 10.1016/j.molcel.2022.07.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/31/2022] [Accepted: 07/16/2022] [Indexed: 12/24/2022]
Abstract
Aberrant replication causes cells lacking BRCA2 to enter mitosis with under-replicated DNA, which activates a repair mechanism known as mitotic DNA synthesis (MiDAS). Here, we identify genome-wide the sites where MiDAS reactions occur when BRCA2 is abrogated. High-resolution profiling revealed that these sites are different from MiDAS at aphidicolin-induced common fragile sites in that they map to genomic regions replicating in the early S-phase, which are close to early-firing replication origins, are highly transcribed, and display R-loop-forming potential. Both transcription inhibition in early S-phase and RNaseH1 overexpression reduced MiDAS in BRCA2-deficient cells, indicating that transcription-replication conflicts (TRCs) and R-loops are the source of MiDAS. Importantly, the MiDAS sites identified in BRCA2-deficient cells also represent hotspots for genomic rearrangements in BRCA2-mutated breast tumors. Thus, our work provides a mechanism for how tumor-predisposing BRCA2 inactivation links transcription-induced DNA damage with mitotic DNA repair to fuel the genomic instability characteristic of cancer cells.
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Affiliation(s)
- Florian J Groelly
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Rebecca A Dagg
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | | | - Giacomo G Rossetti
- Department of Molecular Biology, University of Geneva, 1205 Geneva, Switzerland
| | - Birbal Prasad
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Andreas Panagopoulos
- Department of Molecular Mechanisms of Disease, University of Zurich, 8057 Zurich, Switzerland
| | - Teressa Paulsen
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | | | - Samuel E Jones
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Fena Ochs
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Vasilis S Dionellis
- Department of Molecular Biology, University of Geneva, 1205 Geneva, Switzerland
| | - Emilia Puig Lombardi
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Matthieu J Miossec
- Bioinformatics and Statistical Genetics Core, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Helen Lockstone
- Bioinformatics and Statistical Genetics Core, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Gaëlle Legube
- LBCMCP, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse 31062, France
| | - Andrew N Blackford
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Matthias Altmeyer
- Department of Molecular Mechanisms of Disease, University of Zurich, 8057 Zurich, Switzerland
| | - Thanos D Halazonetis
- Department of Molecular Biology, University of Geneva, 1205 Geneva, Switzerland.
| | - Madalena Tarsounas
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK.
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79
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Petermann E. Conflicts with transcription make early replication late. Mol Cell 2022; 82:3315-3317. [PMID: 36113410 DOI: 10.1016/j.molcel.2022.08.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 08/17/2022] [Accepted: 08/17/2022] [Indexed: 11/19/2022]
Abstract
By sequencing sites of mitotic DNA synthesis in cells lacking homologous recombination, Groelly, Bhowmick, and colleagues show how conflicts between transcription and replication in early S phase can cause under-replicated DNA to persist into mitosis.
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Affiliation(s)
- Eva Petermann
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2TT, UK; Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK.
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80
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Gómez-Cabello D, Pappas G, Aguilar-Morante D, Dinant C, Bartek J. CtIP-dependent nascent RNA expression flanking DNA breaks guides the choice of DNA repair pathway. Nat Commun 2022; 13:5303. [PMID: 36085345 PMCID: PMC9463442 DOI: 10.1038/s41467-022-33027-z] [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: 01/11/2022] [Accepted: 08/29/2022] [Indexed: 11/30/2022] Open
Abstract
The RNA world is changing our views about sensing and resolution of DNA damage. Here, we develop single-molecule DNA/RNA analysis approaches to visualize how nascent RNA facilitates the repair of DNA double-strand breaks (DSBs). RNA polymerase II (RNAPII) is crucial for DSB resolution in human cells. DSB-flanking, RNAPII-generated nascent RNA forms RNA:DNA hybrids, guiding the upstream DNA repair steps towards favouring the error-free Homologous Recombination (HR) pathway over Non-Homologous End Joining. Specific RNAPII inhibitor, THZ1, impairs recruitment of essential HR proteins to DSBs, implicating nascent RNA in DNA end resection, initiation and execution of HR repair. We further propose that resection factor CtIP interacts with and helps re-activate RNAPII when paused by the RNA:DNA hybrids, collectively promoting faithful repair of chromosome breaks to maintain genomic integrity. RNA has been implicated in DNA repair. This work shows that the interplay of RNAPII-generated nascent RNA, RNA:DNA hybrids and the resection factor CtIP guide DNA double strand break repair pathway choice towards error-free homologous recombination.
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Affiliation(s)
- Daniel Gómez-Cabello
- Genome Integrity Group, Danish Cancer Society Research Center, Strandboulevarden 49, Copenhagen, DK-2100, Denmark. .,Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013, Seville, Spain. .,Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012, Seville, Spain.
| | - George Pappas
- Genome Integrity Group, Danish Cancer Society Research Center, Strandboulevarden 49, Copenhagen, DK-2100, Denmark
| | - Diana Aguilar-Morante
- Genome Integrity Group, Danish Cancer Society Research Center, Strandboulevarden 49, Copenhagen, DK-2100, Denmark.,Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013, Seville, Spain
| | - Christoffel Dinant
- Genome Integrity Group, Danish Cancer Society Research Center, Strandboulevarden 49, Copenhagen, DK-2100, Denmark
| | - Jiri Bartek
- Genome Integrity Group, Danish Cancer Society Research Center, Strandboulevarden 49, Copenhagen, DK-2100, Denmark. .,Division of Genome Biology, Department of Medical Biochemistry and Biophysics, Science for Life Laboratory, Karolinska Institute, Scheele's vag 2, Stockholm, 17177, Sweden.
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81
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De Sanctis R, Jacobs F, Benvenuti C, Gaudio M, Franceschini R, Tancredi R, Pedrazzoli P, Santoro A, Zambelli A. From seaside to bedside: Current evidence and future perspectives in the treatment of breast cancer using marine compounds. Front Pharmacol 2022; 13:909566. [PMID: 36160422 PMCID: PMC9495264 DOI: 10.3389/fphar.2022.909566] [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: 03/31/2022] [Accepted: 08/08/2022] [Indexed: 12/02/2022] Open
Abstract
To date, only few marine natural compounds have been proved to be active in breast cancer (BC). The main marine-derived drugs that have been studied for the treatment of BC are tubulin-binding agents (eribulin and plocabulin), DNA-targeting agents (cytarabine and minor groove binders—trabectedin and lurbinectedin) and Antibody-Drug Conjugates (ADCs). Notably, eribulin is the only approved cytotoxic drug for the treatment of advanced BC (ABC), while cytarabine has a limited indication in case of leptomeningeal diffusion of the disease. Also plocabulin showed limited activity in ABC but further research is needed to define its ultimate potential role. The available clinical data for both trabectedin and lurbinectedin are of particular interest in the treatment of BRCA-mutated tumours and HR deficient disease, probably due to a possible immune-mediated mechanism of action. One of the most innovative therapeutic options for the treatment of BC, particularly in TNBC and HER2-positive BC, are ADCs. Some of the ADCs were developed using a specific marine-derived cytotoxic molecule as payload called auristatin. Among these, clinical data are available on ladiratuzumab vedotin and glembatumumab vedotin in TNBC, and on disitamab vedotin and ALT-P7 in HER2-positive patients. A deeper knowledge of the mechanism of action and of the potential predictive factors for response to marine-derived drugs is important for their rational and effective use, alone or in combination. In this narrative review, we discuss the role of marine-derived drugs for the treatment of BC, although most of them are not approved, and the opportunities that could arise from the potential treasure trove of the sea for novel BC therapeutics.
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Affiliation(s)
- Rita De Sanctis
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- Medical Oncology and Hematology Unit, Humanitas Cancer Center, IRCCS Humanitas Research Hospital, Rozzano, Milan, Italy
| | - Flavia Jacobs
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- Medical Oncology and Hematology Unit, Humanitas Cancer Center, IRCCS Humanitas Research Hospital, Rozzano, Milan, Italy
| | - Chiara Benvenuti
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- Medical Oncology and Hematology Unit, Humanitas Cancer Center, IRCCS Humanitas Research Hospital, Rozzano, Milan, Italy
| | - Mariangela Gaudio
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- Medical Oncology and Hematology Unit, Humanitas Cancer Center, IRCCS Humanitas Research Hospital, Rozzano, Milan, Italy
| | - Raul Franceschini
- Department of Chemistry, Università degli studi di Milano Statale, Milan, Italy
| | - Richard Tancredi
- Medical Oncology Unit, ASST Melegnano Martesana, Ospedale A. Uboldo, Milan, Italy
| | - Paolo Pedrazzoli
- Department of Internal Medicine and Medical Therapy, University of Pavia, Pavia, Italy
- Medical Oncology Unit, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Armando Santoro
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- Medical Oncology and Hematology Unit, Humanitas Cancer Center, IRCCS Humanitas Research Hospital, Rozzano, Milan, Italy
| | - Alberto Zambelli
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- Medical Oncology and Hematology Unit, Humanitas Cancer Center, IRCCS Humanitas Research Hospital, Rozzano, Milan, Italy
- *Correspondence: Alberto Zambelli,
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82
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Boni V, Pistilli B, Braña I, Shapiro GI, Trigo J, Moreno V, Castellano D, Fernández C, Kahatt C, Alfaro V, Siguero M, Zeaiter A, Longo F, Zaman K, Antón A, Paredes A, Huidobro G, Subbiah V. Lurbinectedin, a selective inhibitor of oncogenic transcription, in patients with pretreated germline BRCA1/2 metastatic breast cancer: results from a phase II basket study. ESMO Open 2022; 7:100571. [PMID: 36037567 PMCID: PMC9588879 DOI: 10.1016/j.esmoop.2022.100571] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 07/21/2022] [Accepted: 07/27/2022] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Lurbinectedin, a selective inhibitor of oncogenic transcription, has shown preclinical antitumor activity against homologous recombination repair-deficient models and preliminary clinical activity in BRCA1/2 breast cancer. PATIENTS AND METHODS This phase II basket multitumor trial (NCT02454972) evaluated lurbinectedin 3.2 mg/m2 1-h intravenous infusion every 3 weeks in a cohort of 21 patients with pretreated germline BRCA1/2 breast cancer. Patients with any hormone receptor and human epidermal growth factor receptor 2 status were enrolled. The primary efficacy endpoint was overall response rate (ORR) according to RECIST v1.1. Secondary endpoints included duration of response (DoR), progression-free survival (PFS), overall survival (OS) and safety. RESULTS Confirmed partial response (PR) was observed in six patients [ORR = 28.6%; 95% confidence interval (CI) 11.3% to 52.2%] who had received a median of two prior advanced chemotherapy lines. Lurbinectedin was active in both BRCA mutations: four PRs in 11 patients (36.4%) with BRCA2 and two PRs in 10 patients (20.0%) with BRCA1. Median DoR was 8.6 months, median PFS was 4.1 months and median OS was 16.1 months. Stable disease (SD) was observed in 10 patients (47.6%), including 3 with unconfirmed response in a subsequent tumor assessment [ORR unconfirmed = 42.9% (95% CI 21.8% to 66.0%)]. Clinical benefit rate (PR + SD ≥ 4 months) was 76.2% (95% CI 52.8% to 91.8%). No objective response was observed among patients who had received prior poly (ADP-ribose) polymerase inhibitors. The most common treatment-related adverse events (AEs) were nausea (61.9%), fatigue (38.1%) and vomiting (23.8%). These AEs were mostly grade 1/2. The most common grade 3/4 toxicity was neutropenia (42.9%: grade 4, 23.8%: with no febrile neutropenia). CONCLUSIONS This phase II study met its primary endpoint and showed activity of lurbinectedin in germline BRCA1/2 breast cancer. Lurbinectedin showed a predictable and manageable safety profile. Considering the exploratory aim of this trial as well as previous results in other phase II studies, further development of lurbinectedin in this indication is warranted.
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Affiliation(s)
- V Boni
- START Madrid-CIOCC, Centro Integral Oncológico Clara Campal, Madrid, Spain
| | | | - I Braña
- Hospital Universitario Vall D'Hebron (VHIO), Barcelona, Spain
| | | | - J Trigo
- Hospital Universitario Virgen De La Victoria, IBIMA, Málaga, Spain
| | - V Moreno
- START Madrid-FJD, Hospital Universitario Fundación Jiménez Díaz, Madrid, Spain
| | - D Castellano
- Hospital Universitario 12 de Octubre, Madrid, Spain
| | | | - C Kahatt
- PharmaMar, Colmenar Viejo, Madrid, Spain
| | - V Alfaro
- PharmaMar, Colmenar Viejo, Madrid, Spain
| | - M Siguero
- PharmaMar, Colmenar Viejo, Madrid, Spain
| | - A Zeaiter
- PharmaMar, Colmenar Viejo, Madrid, Spain
| | - F Longo
- Hospital Universitario Ramón y Cajal, Madrid, Spain
| | - K Zaman
- University Hospital CHUV, Lausanne, Switzerland
| | - A Antón
- Hospital Universitario Miguel Servet, Zaragoza, Spain
| | - A Paredes
- Hospital Universitario Donostia, Donostia-San Sebastián, Spain
| | - G Huidobro
- Hospital Universitario de Vigo Alvaro Cunqueiro, Pontevedra, Spain
| | - V Subbiah
- The University of Texas MD Anderson Cancer Center, Houston, USA.
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83
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DNA Damage Regulates the Functions of the RNA Binding Protein Sam68 through ATM-Dependent Phosphorylation. Cancers (Basel) 2022; 14:cancers14163847. [PMID: 36010841 PMCID: PMC9405969 DOI: 10.3390/cancers14163847] [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: 04/29/2022] [Revised: 07/26/2022] [Accepted: 08/05/2022] [Indexed: 12/11/2022] Open
Abstract
Simple Summary Alterations of the complex network of interactions between the DNA damage response pathway and RNA metabolism have been described in several tumors, and increasing efforts are devoted to the elucidation of the molecular mechanisms involved in this network. Previous large-scale proteomic studies identified the RNA binding protein Sam68 as a putative target of the ATM kinase. Herein, we demonstrate that ATM phosphorylates Sam68 upon DNA damage induction, and this post-translational modification regulates both the signaling function of Sam68 in the initial phase of the DNA damage response and its RNA processing activity. Thus, our study uncovers anew crosstalk between ATM and Sam68, which may represent a paradigm for the functional interaction between the DDR pathway and RNA binding proteins, and a possible actionabletarget in human cancers. Abstract Cancer cells frequently exhibit dysregulation of the DNA damage response (DDR), genomic instability, and altered RNA metabolism. Recent genome-wide studies have strongly suggested an interaction between the pathways involved in the cellular response to DDR and in the regulation of RNA metabolism, but the molecular mechanism(s) involved in this crosstalk are largely unknown. Herein, we found that activation of the DDR kinase ATM promotes its interaction with Sam68, leading to phosphorylation of this multifunctional RNA binding protein (RBP) on three residues: threonine 61, serine 388 and serine 390. Moreover, we demonstrate that ATM-dependent phosphorylation of threonine 61 promotes the function of Sam68 in the DDR pathway and enhances its RNA processing activity. Importantly, ATM-mediated phosphorylation of Sam68 in prostate cancer cells modulates alternative polyadenylation of transcripts that are targets of Sam68, supporting the notion that the ATM–Sam68 axis exerts a multifaceted role in the response to DNA damage. Thus, our work validates Sam68 as an ATM kinase substrate and uncovers an unexpected bidirectional interplay between ATM and Sam68, which couples the DDR pathway to modulation of RNA metabolism in response to genotoxic stress.
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84
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Petermann E, Lan L, Zou L. Sources, resolution and physiological relevance of R-loops and RNA-DNA hybrids. Nat Rev Mol Cell Biol 2022; 23:521-540. [PMID: 35459910 DOI: 10.1038/s41580-022-00474-x] [Citation(s) in RCA: 118] [Impact Index Per Article: 59.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2022] [Indexed: 12/12/2022]
Abstract
RNA-DNA hybrids are generated during transcription, DNA replication and DNA repair and are crucial intermediates in these processes. When RNA-DNA hybrids are stably formed in double-stranded DNA, they displace one of the DNA strands and give rise to a three-stranded structure called an R-loop. R-loops are widespread in the genome and are enriched at active genes. R-loops have important roles in regulating gene expression and chromatin structure, but they also pose a threat to genomic stability, especially during DNA replication. To keep the genome stable, cells have evolved a slew of mechanisms to prevent aberrant R-loop accumulation. Although R-loops can cause DNA damage, they are also induced by DNA damage and act as key intermediates in DNA repair such as in transcription-coupled repair and RNA-templated DNA break repair. When the regulation of R-loops goes awry, pathological R-loops accumulate, which contributes to diseases such as neurodegeneration and cancer. In this Review, we discuss the current understanding of the sources of R-loops and RNA-DNA hybrids, mechanisms that suppress and resolve these structures, the impact of these structures on DNA repair and genome stability, and opportunities to therapeutically target pathological R-loops.
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Affiliation(s)
- Eva Petermann
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Centre for Genome Biology, University of Birmingham, Birmingham, UK
| | - Li Lan
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, MA, USA
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Lee Zou
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, MA, USA.
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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85
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Kumar A, Fournier LA, Stirling PC. Integrative analysis and prediction of human R-loop binding proteins. G3 (BETHESDA, MD.) 2022; 12:jkac142. [PMID: 35666183 PMCID: PMC9339281 DOI: 10.1093/g3journal/jkac142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
In the past decade, there has been a growing appreciation for R-loop structures as important regulators of the epigenome, telomere maintenance, DNA repair, and replication. Given these numerous functions, dozens, or potentially hundreds, of proteins could serve as direct or indirect regulators of R-loop writing, reading, and erasing. In order to understand common properties shared amongst potential R-loop binding proteins, we mined published proteomic studies and distilled 10 features that were enriched in R-loop binding proteins compared with the rest of the proteome. Applying an easy-ensemble machine learning approach, we used these R-loop binding protein-specific features along with their amino acid composition to create random forest classifiers that predict the likelihood of a protein to bind to R-loops. Known R-loop regulating pathways such as splicing, DNA damage repair and chromatin remodeling are highly enriched in our datasets, and we validate 2 new R-loop binding proteins LIG1 and FXR1 in human cells. Together these datasets provide a reference to pursue analyses of novel R-loop regulatory proteins.
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Affiliation(s)
| | | | - Peter C Stirling
- Corresponding author: Terry Fox Laboratory, BC Cancer, Vancouver, BC V5Z1L3, Canada.
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86
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Saha S, Yang X, Huang SYN, Agama K, Baechler SA, Sun Y, Zhang H, Saha LK, Su S, Jenkins LM, Wang W, Pommier Y. Resolution of R-loops by topoisomerase III-β (TOP3B) in coordination with the DEAD-box helicase DDX5. Cell Rep 2022; 40:111067. [PMID: 35830799 PMCID: PMC10575568 DOI: 10.1016/j.celrep.2022.111067] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 04/20/2022] [Accepted: 06/16/2022] [Indexed: 11/16/2022] Open
Abstract
The present study demonstrates how TOP3B is involved in resolving R-loops. We observed elevated R-loops in TOP3B knockout cells (TOP3BKO), which are suppressed by TOP3B transfection. R-loop-inducing agents, the topoisomerase I inhibitor camptothecin, and the splicing inhibitor pladienolide-B also induce higher R-loops in TOP3BKO cells. Camptothecin- and pladienolide-B-induced R-loops are concurrent with the induction of TOP3B cleavage complexes (TOP3Bccs). RNA/DNA hybrid IP-western blotting show that TOP3B is physically associated with R-loops. Biochemical assays using recombinant TOP3B and oligonucleotides mimicking R-loops show that TOP3B cleaves the single-stranded DNA displaced by the R-loop RNA-DNA duplex. IP-mass spectrometry and IP-western experiments reveal that TOP3B interacts with the R-loop helicase DDX5 independently of TDRD3. Finally, we demonstrate that DDX5 and TOP3B are epistatic in resolving R-loops in a pathway parallel with senataxin. We propose a decatenation model for R-loop resolution by TOP3B-DDX5 protecting cells from R-loop-induced damage.
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Affiliation(s)
- Sourav Saha
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Xi Yang
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Shar-Yin Naomi Huang
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Keli Agama
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Simone Andrea Baechler
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Yilun Sun
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Hongliang Zhang
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Liton Kumar Saha
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Shuaikun Su
- Laboratory of Genetics and Genomics, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Lisa M Jenkins
- Collaborative Protein Technology Resource, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Weidong Wang
- Laboratory of Genetics and Genomics, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Yves Pommier
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA.
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87
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Wang Y, Ma B, Liu X, Gao G, Che Z, Fan M, Meng S, Zhao X, Sugimura R, Cao H, Zhou Z, Xie J, Lin C, Luo Z. ZFP281-BRCA2 prevents R-loop accumulation during DNA replication. Nat Commun 2022; 13:3493. [PMID: 35715464 PMCID: PMC9205938 DOI: 10.1038/s41467-022-31211-9] [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: 01/29/2021] [Accepted: 06/08/2022] [Indexed: 11/16/2022] Open
Abstract
R-loops are prevalent in mammalian genomes and involved in many fundamental cellular processes. Depletion of BRCA2 leads to aberrant R-loop accumulation, contributing to genome instability. Here, we show that ZFP281 cooperates with BRCA2 in preventing R-loop accumulation to facilitate DNA replication in embryonic stem cells. ZFP281 depletion reduces PCNA levels on chromatin and impairs DNA replication. Mechanistically, we demonstrate that ZFP281 can interact with BRCA2, and that BRCA2 is enriched at G/C-rich promoters and requires both ZFP281 and PRC2 for its proper recruitment to the bivalent chromatin at the genome-wide scale. Furthermore, depletion of ZFP281 or BRCA2 leads to accumulation of R-loops over the bivalent regions, and compromises activation of the developmental genes by retinoic acid during stem cell differentiation. In summary, our results reveal that ZFP281 recruits BRCA2 to the bivalent chromatin regions to ensure proper progression of DNA replication through preventing persistent R-loops. R-loops are prevalent in mammalian genomes and involved in many fundamental cellular processes. Here, Wang et al. report that ZFP281 cooperates with BRCA2 in preventing R-loop accumulation to facilitate DNA replication in embryonic stem cells.
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Affiliation(s)
- Yan Wang
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Binbin Ma
- Institute for Regenerative Medicine, Shanghai East Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Xiaoxu Liu
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Ge Gao
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, 999077, China
| | - Zhuanzhuan Che
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Menghan Fan
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Siyan Meng
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Xiru Zhao
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Rio Sugimura
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, 999077, China
| | - Hua Cao
- Key Laboratory of Technical Evaluation of Fertility Regulation of Non-human primate, Fujian Provincial Maternity and Children's Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, China
| | - Zhongjun Zhou
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, 999077, China
| | - Jing Xie
- Institute for Regenerative Medicine, Shanghai East Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Chengqi Lin
- Key Laboratory of Technical Evaluation of Fertility Regulation of Non-human primate, Fujian Provincial Maternity and Children's Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, China. .,Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China. .,Shenzhen Research Institute, Southeast University, 19 Gaoxin South 4th Road, Nanshan District, Shenzhen, 518063, China.
| | - Zhuojuan Luo
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China. .,Shenzhen Research Institute, Southeast University, 19 Gaoxin South 4th Road, Nanshan District, Shenzhen, 518063, China.
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88
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Shih HT, Chen WY, Wang HY, Chao T, Huang HD, Chou CH, Chang ZF. DNMT3b protects centromere integrity by restricting R-loop-mediated DNA damage. Cell Death Dis 2022; 13:546. [PMID: 35688824 PMCID: PMC9187704 DOI: 10.1038/s41419-022-04989-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 05/26/2022] [Accepted: 05/30/2022] [Indexed: 01/21/2023]
Abstract
This study used DNA methyltransferase 3b (DNMT3b) knockout cells and the functional loss of DNMT3b mutation in immunodeficiency-centromeric instability-facial anomalies syndrome (ICF) cells to understand how DNMT3b dysfunction causes genome instability. We demonstrated that R-loops contribute to DNA damages in DNMT3b knockout and ICF cells. More prominent DNA damage signal in DNMT3b knockout cells was due to the loss of DNMT3b expression and the acquirement of p53 mutation. Genome-wide ChIP-sequencing mapped DNA damage sites at satellite repetitive DNA sequences including (peri-)centromere regions. However, the steady-state levels of (peri-)centromeric R-loops were reduced in DNMT3b knockout and ICF cells. Our analysis indicates that XPG and XPF endonucleases-mediated cleavages remove (peri-)centromeric R-loops to generate DNA beaks, causing chromosome instability. DNMT3b dysfunctions clearly increase R-loops susceptibility to the cleavage process. Finally, we showed that DNA double-strand breaks (DSBs) in centromere are probably repaired by error-prone end-joining pathway in ICF cells. Thus, DNMT3 dysfunctions undermine the integrity of centromere by R-loop-mediated DNA damages and repair.
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Affiliation(s)
- Hsueh-Tzu Shih
- Institute of Molecular Medicine, National Taiwan University, Taipei, 10051, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Wei-Yi Chen
- Institute of Biochemistry and Molecular Biology, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan
- Cancer Progression Research Center, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan
| | - Hsin-Yen Wang
- Institute of Molecular Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Tung Chao
- Institute of Molecular Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Hsien-Da Huang
- Warshel Institute for Computational Biology, The Chinese University of Hong Kong, Longgang District, 518172, Shenzhen, China
- School of Life and Health Sciences, The Chinese University of Hong Kong, Longgang District, 518172, Shenzhen, China
- School of Medicine, The Chinese University of Hong Kong, Longgang District, 518172, Shenzhen, China
| | - Chih-Hung Chou
- Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan
- Center for Intelligent Drug Systems and Smart Bio-devices (IDS2B), National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan
| | - Zee-Fen Chang
- Institute of Molecular Medicine, National Taiwan University, Taipei, 10051, Taiwan.
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan.
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89
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Devico Marciano N, Kroening G, Dayyani F, Zell JA, Lee FC, Cho M, Valerin JG. BRCA-Mutated Pancreatic Cancer: From Discovery to Novel Treatment Paradigms. Cancers (Basel) 2022; 14:cancers14102453. [PMID: 35626055 PMCID: PMC9140002 DOI: 10.3390/cancers14102453] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 05/02/2022] [Accepted: 05/13/2022] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Approximately 10–20% of pancreatic cancer patients will have a mutation in their DNA, passed on in families, that contributes to the development of their pancreatic cancer. These mutations are important in that they effect the biology of the disease as well as contribute to sensitivity to specific treatments. We describe the critical role that these genes play in various cellular processes in the body that contribute to their role in cancer development and normal cellular function. In this review, we aim to describe the role of certain genes (BRCA1 and BRCA2) in the development of pancreatic cancer and the current and future research efforts underway to treat this subtype of disease. Abstract The discovery of BRCA1 and BRCA2 in the 1990s revolutionized the way we research and treat breast, ovarian, and pancreatic cancers. In the case of pancreatic cancers, germline mutations occur in about 10–20% of patients, with mutations in BRCA1 and BRCA2 being the most common. BRCA genes are critical in DNA repair pathways, particularly in homologous recombination, which has a serious impact on genomic stability and can contribute to cancerous cell proliferation. However, BRCA1 also plays a fundamental role in cell cycle checkpoint control, ubiquitination, control of gene expression, and chromatin remodeling, while BRCA2 also plays a role in transcription and immune system response. Therefore, mutations in these genes lead to multiple defects in cells that may be utilized when treating cancer. BRCA mutations seem to confer a prognostic benefit with an improved overall survival due to differing underlying biology. These mutations also appear to be a predictive marker, with patients showing increased sensitivity to certain treatments, such as platinum chemotherapy and PARP inhibitors. Olaparib is currently indicated for maintenance therapy in metastatic PDAC after induction with platinum-based chemotherapy. Resistance has been found to these therapies, and with a 10.8% five-year OS, novel therapies are desperately needed.
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90
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Brickner JR, Garzon JL, Cimprich KA. Walking a tightrope: The complex balancing act of R-loops in genome stability. Mol Cell 2022; 82:2267-2297. [PMID: 35508167 DOI: 10.1016/j.molcel.2022.04.014] [Citation(s) in RCA: 81] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/28/2022] [Accepted: 04/10/2022] [Indexed: 12/14/2022]
Abstract
Although transcription is an essential cellular process, it is paradoxically also a well-recognized cause of genomic instability. R-loops, non-B DNA structures formed when nascent RNA hybridizes to DNA to displace the non-template strand as single-stranded DNA (ssDNA), are partially responsible for this instability. Yet, recent work has begun to elucidate regulatory roles for R-loops in maintaining the genome. In this review, we discuss the cellular contexts in which R-loops contribute to genomic instability, particularly during DNA replication and double-strand break (DSB) repair. We also summarize the evidence that R-loops participate as an intermediate during repair and may influence pathway choice to preserve genomic integrity. Finally, we discuss the immunogenic potential of R-loops and highlight their links to disease should they become pathogenic.
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Affiliation(s)
- Joshua R Brickner
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jada L Garzon
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Karlene A Cimprich
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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91
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Kucherlapati MH. Co-expression patterns explain how a basic transcriptional role for MYC modulates Wnt and MAPK pathways in colon and lung adenocarcinomas. Cell Cycle 2022; 21:1619-1638. [PMID: 35438040 PMCID: PMC9291661 DOI: 10.1080/15384101.2022.2060454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
A subset of proliferation genes that are associated with origin licensing, firing, and DNA synthesis has been compared to known drivers of colon (COAD) and lung (LUAD) adenocarcinomas using Spearman's rank correlation coefficients. The frequency with which APC, CTNNB1, KRAS, MYC, Braf, TP53, Rb1, EGFR, and cell cycle components have direct or indirect co-expression with the proliferation factors permits identification of their expression relative to the G1-S phase of the cell cycle. Here, adenomatous polyposis coli (APC), a negative regulator of Wnt signaling known to function through MYC, indirectly co-expresses at the same frequency as proliferation genes in both COAD and LUAD, consistent with M phase expression. However, APC is indirectly co-expressed with MYC and is found mutated only in COAD. MYC is thought to function at the interface of transcription and replication, acting through the SWI/SNF chromatin remodeling complex, and increased or decreased expression of MYC can induce or repress tumorigenesis, respectively. These data suggest that transcription of APC during the M phase with low MYC co-expression contributes by an unknown mechanism to APC mutations and Wnt pathway deregulation in COAD and that upper and lower limits of MYC expression, enforced by the cell cycle, may influence cancer differentially. Other Wnt signaling components co-expressed in the low MYC context in COAD also have significantly higher mutation frequencies, supporting the hypothesis. Additionally, Braf is found here to have direct co-expression with multiple proliferation factors in non-EGFR activated LUAD, and EGFR-activated LUAD are completely deregulated with respect to E2F(s) 4/5/6 expression, potentially explaining the low proliferation rates seen in LUAD.
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Affiliation(s)
- Melanie Haas Kucherlapati
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Division of Genetics, Brigham and Women's Hospital, Boston, Massachusetts, USA
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Mishra AP, Hartford SA, Sahu S, Klarmann K, Chittela RK, Biswas K, Jeon AB, Martin BK, Burkett S, Southon E, Reid S, Albaugh ME, Karim B, Tessarollo L, Keller JR, Sharan SK. BRCA2-DSS1 interaction is dispensable for RAD51 recruitment at replication-induced and meiotic DNA double strand breaks. Nat Commun 2022; 13:1751. [PMID: 35365640 PMCID: PMC8975877 DOI: 10.1038/s41467-022-29409-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 03/14/2022] [Indexed: 12/31/2022] Open
Abstract
The interaction between tumor suppressor BRCA2 and DSS1 is essential for RAD51 recruitment and repair of DNA double stand breaks (DSBs) by homologous recombination (HR). We have generated mice with a leucine to proline substitution at position 2431 of BRCA2, which disrupts this interaction. Although a significant number of mutant mice die during embryogenesis, some homozygous and hemizygous mutant mice undergo normal postnatal development. Despite lack of radiation induced RAD51 foci formation and a severe HR defect in somatic cells, mutant mice are fertile and exhibit normal RAD51 recruitment during meiosis. We hypothesize that the presence of homologous chromosomes in close proximity during early prophase I may compensate for the defect in BRCA2-DSS1 interaction. We show the restoration of RAD51 foci in mutant cells when Topoisomerase I inhibitor-induced single strand breaks are converted into DSBs during DNA replication. We also partially rescue the HR defect by tethering the donor DNA to the site of DSBs using streptavidin-fused Cas9. Our findings demonstrate that the BRCA2-DSS1 complex is dispensable for RAD51 loading when the homologous DNA is close to the DSB. Mishra et al. have generated mice with a single amino acid substitution in BRCA2, which disrupts its interaction with DSS1 resulting in a severe HR defect. They show the interaction to be dispensable for HR at replication induced and meiotic DSBs.
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Affiliation(s)
- Arun Prakash Mishra
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Suzanne A Hartford
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.,Regeneron Pharmaceuticals, Inc, Tarrytown, NY, USA
| | - Sounak Sahu
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Kimberly Klarmann
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.,Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, NCI, Frederick, MD, USA
| | - Rajani Kant Chittela
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.,Applied Genomics Section, Bhabha Atomic Research Center, Trombay, Mumbai, India
| | - Kajal Biswas
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Albert B Jeon
- Molecular Histopathology Laboratory, Leidos Biomedical Research, Inc. Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Betty K Martin
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.,Laboratory Animal Sciences Program, Leidos Biomedical Research, Inc. Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Sandra Burkett
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Eileen Southon
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Susan Reid
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Mary E Albaugh
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.,Laboratory Animal Sciences Program, Leidos Biomedical Research, Inc. Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Baktiar Karim
- Molecular Histopathology Laboratory, Leidos Biomedical Research, Inc. Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Lino Tessarollo
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Jonathan R Keller
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.,Basic Science Program, Leidos Biomedical Research, Inc. Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Shyam K Sharan
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.
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93
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Shah SM, Demidova EV, Lesh RW, Hall MJ, Daly MB, Meyer JE, Edelman MJ, Arora S. Therapeutic implications of germline vulnerabilities in DNA repair for precision oncology. Cancer Treat Rev 2022; 104:102337. [PMID: 35051883 PMCID: PMC9016579 DOI: 10.1016/j.ctrv.2021.102337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/30/2021] [Accepted: 12/31/2021] [Indexed: 12/12/2022]
Abstract
DNA repair vulnerabilities are present in a significant proportion of cancers. Specifically, germline alterations in DNA repair not only increase cancer risk but are associated with treatment response and clinical outcomes. The therapeutic landscape of cancer has rapidly evolved with the FDA approval of therapies that specifically target DNA repair vulnerabilities. The clinical success of synthetic lethality between BRCA deficiency and poly(ADP-ribose) polymerase (PARP) inhibition has been truly revolutionary. Defective mismatch repair has been validated as a predictor of response to immune checkpoint blockade associated with durable responses and long-term benefit in many cancer patients. Advances in next generation sequencing technologies and their decreasing cost have supported increased genetic profiling of tumors coupled with germline testing of cancer risk genes in patients. The clinical adoption of panel testing for germline assessment in high-risk individuals has generated a plethora of genetic data, particularly on DNA repair genes. Here, we highlight the therapeutic relevance of germline aberrations in DNA repair to identify patients eligible for precision treatments such as PARP inhibitors (PARPis), immune checkpoint blockade, chemotherapy, radiation therapy and combined treatment. We also discuss emerging mechanisms that regulate DNA repair.
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Affiliation(s)
- Shreya M Shah
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, PA, United States; Science Scholars Program, Temple University, Philadelphia, PA, United States
| | - Elena V Demidova
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, PA, United States; Kazan Federal University, Kazan, Russian Federation
| | - Randy W Lesh
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, PA, United States; Geisinger Commonwealth School of Medicine, Scranton, PA, United States
| | - Michael J Hall
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, PA, United States; Department of Clinical Genetics, Fox Chase Cancer Center, Philadelphia, PA, United States
| | - Mary B Daly
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, PA, United States; Department of Clinical Genetics, Fox Chase Cancer Center, Philadelphia, PA, United States
| | - Joshua E Meyer
- Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, United States; Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, PA, United States
| | - Martin J Edelman
- Department of Hematology/Oncology, Fox Chase Cancer Center, Philadelphia, PA, United States.
| | - Sanjeevani Arora
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, PA, United States; Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, United States.
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94
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Abstract
DNA repair and DNA damage signaling pathways are critical for the maintenance of genomic stability. Defects of DNA repair and damage signaling contribute to tumorigenesis, but also render cancer cells vulnerable to DNA damage and reliant on remaining repair and signaling activities. Here, we review the major classes of DNA repair and damage signaling defects in cancer, the genomic instability that they give rise to, and therapeutic strategies to exploit the resulting vulnerabilities. Furthermore, we discuss the impacts of DNA repair defects on both targeted therapy and immunotherapy, and highlight emerging principles for targeting DNA repair defects in cancer therapy.
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Affiliation(s)
- Jessica L Hopkins
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Li Lan
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Lee Zou
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
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95
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Yasuhara T, Kato R, Yamauchi M, Uchihara Y, Zou L, Miyagawa K, Shibata A. RAP80 suppresses the vulnerability of R-loops during DNA double-strand break repair. Cell Rep 2022; 38:110335. [PMID: 35108530 DOI: 10.1016/j.celrep.2022.110335] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 12/08/2021] [Accepted: 01/12/2022] [Indexed: 01/15/2023] Open
Abstract
Single-stranded DNA (ssDNA) arising as an intermediate of cellular processes on DNA is a potential vulnerability of the genome unless it is appropriately protected. Recent evidence suggests that R-loops, consisting of ssDNA and DNA-RNA hybrids, can form in the proximity of DNA double-strand breaks (DSBs) within transcriptionally active regions. However, how the vulnerability of ssDNA in R-loops is overcome during DSB repair remains unclear. Here, we identify RAP80 as a factor suppressing the vulnerability of ssDNA in R-loops, chromosome translocations, and deletions during DSB repair. Mechanistically, RAP80 prevents unscheduled nucleolytic processing of ssDNA in R-loops by CtIP. This mechanism promotes efficient DSB repair via transcription-associated end joining dependent on BRCA1, Polθ, and LIG1/3. Thus, RAP80 suppresses the vulnerability of R-loops during DSB repair, thereby precluding genomic abnormalities in a critical component of the genome caused by deleterious R-loop processing.
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Affiliation(s)
- Takaaki Yasuhara
- Laboratory of Molecular Radiology, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, MA, USA.
| | - Reona Kato
- Laboratory of Molecular Radiology, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Motohiro Yamauchi
- Hospital Campus Laboratory, Radioisotope Center, Central Institute of Radioisotope Science and Safety Management, Kyushu University, Fukuoka, Japan
| | - Yuki Uchihara
- Gunma University Initiative for Advanced Research, Gunma University, Maebashi, Gunma, Japan
| | - Lee Zou
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, MA, USA; Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Kiyoshi Miyagawa
- Laboratory of Molecular Radiology, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
| | - Atsushi Shibata
- Gunma University Initiative for Advanced Research, Gunma University, Maebashi, Gunma, Japan.
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96
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Badra Fajardo N, Taraviras S, Lygerou Z. Fanconi anemia proteins and genome fragility: unraveling replication defects for cancer therapy. Trends Cancer 2022; 8:467-481. [DOI: 10.1016/j.trecan.2022.01.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 01/25/2022] [Indexed: 10/19/2022]
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97
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Marabitti V, Valenzisi P, Lillo G, Malacaria E, Palermo V, Pichierri P, Franchitto A. R-Loop-Associated Genomic Instability and Implication of WRN and WRNIP1. Int J Mol Sci 2022; 23:ijms23031547. [PMID: 35163467 PMCID: PMC8836129 DOI: 10.3390/ijms23031547] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/25/2022] [Accepted: 01/25/2022] [Indexed: 02/05/2023] Open
Abstract
Maintenance of genome stability is crucial for cell survival and relies on accurate DNA replication. However, replication fork progression is under constant attack from different exogenous and endogenous factors that can give rise to replication stress, a source of genomic instability and a notable hallmark of pre-cancerous and cancerous cells. Notably, one of the major natural threats for DNA replication is transcription. Encounters or conflicts between replication and transcription are unavoidable, as they compete for the same DNA template, so that collisions occur quite frequently. The main harmful transcription-associated structures are R-loops. These are DNA structures consisting of a DNA–RNA hybrid and a displaced single-stranded DNA, which play important physiological roles. However, if their homeostasis is altered, they become a potent source of replication stress and genome instability giving rise to several human diseases, including cancer. To combat the deleterious consequences of pathological R-loop persistence, cells have evolved multiple mechanisms, and an ever growing number of replication fork protection factors have been implicated in preventing/removing these harmful structures; however, many others are perhaps still unknown. In this review, we report the current knowledge on how aberrant R-loops affect genome integrity and how they are handled, and we discuss our recent findings on the role played by two fork protection factors, the Werner syndrome protein (WRN) and the Werner helicase-interacting protein 1 (WRNIP1) in response to R-loop-induced genome instability.
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98
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Cortesi L, Venturelli M, Barbieri E, Baldessari C, Bardasi C, Coccia E, Baglio F, Rimini M, Greco S, Napolitano M, Pipitone S, Dominici M. Exceptional response to lurbinectedin and irinotecan in BRCA-mutated platinum-resistant ovarian cancer patient: a case report. Ther Adv Chronic Dis 2022; 13:20406223211063023. [PMID: 35070248 PMCID: PMC8771728 DOI: 10.1177/20406223211063023] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 11/04/2021] [Indexed: 11/16/2022] Open
Abstract
Lurbinectedin is responsible for DNA recognition and binding, producing double-strand DNA (dsDNA) breaks thus resulting in apoptosis. Sensitivity to lurbinectedin is linked to the nucleotide excision repair (NER) system. Furthermore, irinotecan, a topoisomerase I inhibitor, provokes dsDNA breaks that could be reinforced abrogating the NER system using lurbinectedin. BRCA-mutated patients, already treated with platinum-derived drugs, who suffered DNA damage, cannot repair the breaks due to lurbinectedin interaction, whereas irinotecan provokes a dsDNA break that promotes synthetic lethality. This article describes an exceptional response to lurbinectedin alone followed by the association with irinotecan in a BRCA-mutated platinum-resistant ovarian cancer patient. A 44-year-old BRCA1-mutated ovarian cancer patient was treated in sixth line with lurbinectedin and irinotecan with a time to further progression (TTFP) equal to 8 months. In our case, the association with irinotecan overcame the resistance to lurbinectedin alone. In conclusion, lurbinectedin and irinotecan demonstrated a promising response in platinum-resistant patients. However, further studies should be conducted to validate our findings and future trials will be important to further define the clinical utility of lurbinectedin.
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Affiliation(s)
- Laura Cortesi
- Department of Oncology and Hematology, University Hospital of Modena, Via del Pozzo, 71, 41124 Modena, Italy
| | - Marta Venturelli
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Elena Barbieri
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Cinzia Baldessari
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Camilla Bardasi
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Emanuele Coccia
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Federica Baglio
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Margherita Rimini
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Stefano Greco
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Martina Napolitano
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Stefania Pipitone
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
| | - Massimo Dominici
- Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
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99
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Proximity labeling identifies a repertoire of site-specific R-loop modulators. Nat Commun 2022; 13:53. [PMID: 35013239 PMCID: PMC8748879 DOI: 10.1038/s41467-021-27722-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 12/06/2021] [Indexed: 11/11/2022] Open
Abstract
R-loops are three-stranded nucleic acid structures that accumulate on chromatin in neurological diseases and cancers and contribute to genome instability. Using a proximity-dependent labeling system, we identified distinct classes of proteins that regulate R-loops in vivo through different mechanisms. We show that ATRX suppresses R-loops by interacting with RNAs and preventing R-loop formation. Our proteomics screen also discovered an unexpected enrichment for proteins containing zinc fingers and homeodomains. One of the most consistently enriched proteins was activity-dependent neuroprotective protein (ADNP), which is frequently mutated in ASD and causal in ADNP syndrome. We find that ADNP resolves R-loops in vitro and that it is necessary to suppress R-loops in vivo at its genomic targets. Furthermore, deletion of the ADNP homeodomain severely diminishes R-loop resolution activity in vitro, results in R-loop accumulation at ADNP targets, and compromises neuronal differentiation. Notably, patient-derived human induced pluripotent stem cells that contain an ADNP syndrome-causing mutation exhibit R-loop and CTCF accumulation at ADNP targets. Our findings point to a specific role for ADNP-mediated R-loop resolution in physiological and pathological neuronal function and, more broadly, to a role for zinc finger and homeodomain proteins in R-loop regulation, with important implications for developmental disorders and cancers. R-loops are three-stranded nucleic acid structures that contribute to genome instability and accumulate in neurological diseases. Here the authors identify R-loop proximal factors, which are enriched for zinc finger and homeodomain proteins, including activity-dependent neuroprotective protein (ADNP). ADNP plays a role in R-loop resolution and loss-of-function leads to R-loop accumulation.
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100
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Xie J, Wen M, Zhang J, Wang Z, Wang M, Qiu Y, Zhao W, Zhu F, Yao M, Rong ZX, Hu W, Pei Q, Sun X, Li J, Mao Z, Sun L, Tan R. The roles of RNA helicases in DNA damage repair and tumorigenesis reveal precision therapeutic strategies. Cancer Res 2022; 82:872-884. [PMID: 34987058 DOI: 10.1158/0008-5472.can-21-2187] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 11/04/2021] [Accepted: 12/29/2021] [Indexed: 11/16/2022]
Abstract
DEAD-box RNA helicases belong to a large group of RNA processing factors and play vital roles unwinding RNA helices and in ribosomal RNA biogenesis. Emerging evidence indicates that RNA helicases are associated with genome stability, yet the mechanisms behind this association remain poorly understood. In this study, we performed a comprehensive analysis of RNA helicases using multiplatform proteogenomic databases. Over 50% (28/49) of detected RNA helicases were highly expressed in multiple tumor tissues, and more than 60% (17/28) of tumor-associated members were directly involved in DNA damage repair (DDR). Analysis of repair dynamics revealed that these RNA helicases are engaged in an extensively broad range of DDR pathways. Among these factors is DDX21, which was prominently upregulated in colorectal cancer. The high expression of DDX21 gave rise to frequent chromosome exchange and increased genome fragmentation. Mechanistically, aberrantly high expression of DDX21 triggered inappropriate repair processes by delaying homologous recombination repair and increasing replication stress, leading to genome instability and tumorigenesis. Treatment with distinct chemotherapeutic drugs caused higher lethality to cancer cells with genome fragility induced by DDX21, providing a perspective for treatment of tumors with high DDX21 expression. This study revealed the role of RNA helicases in DNA damage and their associations with cancer, which could expand therapeutic strategies and improve precision treatments for cancer patients with high expression of RNA helicases.
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Affiliation(s)
- Jinru Xie
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Central South University
| | - Ming Wen
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Central South University
| | - Jiao Zhang
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Central South University
| | - Zheng Wang
- Department of Geriatrics, Central South University
| | - Meng Wang
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Central South University
| | - Yanfang Qiu
- Center for Molecular Medicine, Central South University
| | - Wenchao Zhao
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Central South University
| | - Fang Zhu
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Central South University
| | - Mianfeng Yao
- Department of Stomatology, Xiangya Hospital Central South University
| | - Zhuo-Xian Rong
- Center for Molecular Medicine, Key Laboratory of Molecular Radiation Oncology, Hunan Province, Xiangya Hospital, Central South University, Changsha, 410078, China
| | - Wenfeng Hu
- Center for Molecular Medicine, Xiangya Hospital Central South University
| | - Qian Pei
- Xiangya Hospital Central South University
| | - Xiaoxiang Sun
- School of Life Sciences and Technology, Tongji University
| | - Jinchen Li
- Department of Geriatrics, Central South University
| | - Zhiyong Mao
- School of Life Sciences and Technology, Tongji University
| | | | - Rong Tan
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Central South University
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