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Palma A, Grande S, Ricci-Vitiani L, Luciani AM, Buccarelli M, Biffoni M, Dini V, Cirrone GAP, Ciocca M, Guidoni L, Pallini R, Viti V, Rosi A. Different Mechanisms Underlie the Metabolic Response of GBM Stem-Like Cells to Ionizing Radiation: Biological and MRS Studies on Effects of Photons and Carbon Ions. Int J Mol Sci 2020; 21:ijms21145167. [PMID: 32708312 PMCID: PMC7404344 DOI: 10.3390/ijms21145167] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/18/2020] [Accepted: 07/20/2020] [Indexed: 12/13/2022] Open
Abstract
Glioblastoma multiforme (GBM) is a malignant primary brain tumor with very poor prognosis, high recurrence rate, and failure of chemo-radiotherapy, mainly due to a small fraction of cells with stem-like properties (GSCs). To study the mechanisms of GSCs resistance to radiation, two GSC lines, named line #1 and line #83, with different metabolic patterns and clinical outcome, were irradiated with photon beams and carbon ions and assessed by 1H Magnetic Resonance Spectroscopy (MRS). Both irradiation modalities induced early cytotoxic effects in line #1 with small effects on cell cycle, whereas a proliferative G2/M cytostatic block was observed in line #83. MR spectroscopy signals from mobile lipids (ML) increased in spectra of line #1 after photon and C-ion irradiation with effects on lipid unsaturation level, whereas no effects were detected in line #83 spectra. Gamma-Aminobutyric Acid (GABA), glutamic acid (glu) and Phosphocreatine (pCr) signals showed a significant variation only for line #1 after carbon ion irradiation. Glucose (glc) level and lactate (Lac) extrusion behaved differently in the two lines. Our findings suggest that the differences in irradiation response of GSCs #1 and #83 lines are likely attributable to their different metabolic fingerprint rather than to the different radiation types.
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Affiliation(s)
- Alessandra Palma
- National Centre for Innovative Technologies in Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (A.P.); (S.G.); (A.M.L.); (V.D.); (L.G.); (V.V.)
| | - Sveva Grande
- National Centre for Innovative Technologies in Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (A.P.); (S.G.); (A.M.L.); (V.D.); (L.G.); (V.V.)
| | - Lucia Ricci-Vitiani
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, 00161 Rome, Italy; (L.R.-V.); (M.B.); (M.B.)
| | - Anna Maria Luciani
- National Centre for Innovative Technologies in Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (A.P.); (S.G.); (A.M.L.); (V.D.); (L.G.); (V.V.)
| | - Mariachiara Buccarelli
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, 00161 Rome, Italy; (L.R.-V.); (M.B.); (M.B.)
| | - Mauro Biffoni
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, 00161 Rome, Italy; (L.R.-V.); (M.B.); (M.B.)
| | - Valentina Dini
- National Centre for Innovative Technologies in Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (A.P.); (S.G.); (A.M.L.); (V.D.); (L.G.); (V.V.)
- Istituto Nazionale di Fisica Nucleare INFN Sez. di Roma, 00185 Rome, Italy
| | - Giuseppe A. P. Cirrone
- National Institute for Nuclear Physics, Laboratori Nazionali del Sud, INFN-LNS, 95123 Catania, Italy;
| | - Mario Ciocca
- Centro Nazionale di Adroterapia Oncologica (CNAO)-National Center for Oncological Hadrontherapy, 27100 Pavia, Italy;
| | - Laura Guidoni
- National Centre for Innovative Technologies in Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (A.P.); (S.G.); (A.M.L.); (V.D.); (L.G.); (V.V.)
| | - Roberto Pallini
- Department of Neuroscience, Fondazione Policlinico Universitario A. Gemelli, Università Cattolica del Sacro Cuore, 00168 Rome, Italy;
| | - Vincenza Viti
- National Centre for Innovative Technologies in Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (A.P.); (S.G.); (A.M.L.); (V.D.); (L.G.); (V.V.)
| | - Antonella Rosi
- National Centre for Innovative Technologies in Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (A.P.); (S.G.); (A.M.L.); (V.D.); (L.G.); (V.V.)
- Correspondence: ; Tel.: +39-06-49903159
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102
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Banuelos CA, Ito Y, Obst JK, Mawji NR, Wang J, Hirayama Y, Leung JK, Tam T, Tien AH, Andersen RJ, Sadar MD. Ralaniten Sensitizes Enzalutamide-Resistant Prostate Cancer to Ionizing Radiation in Prostate Cancer Cells that Express Androgen Receptor Splice Variants. Cancers (Basel) 2020; 12:cancers12071991. [PMID: 32708219 PMCID: PMC7409302 DOI: 10.3390/cancers12071991] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/12/2020] [Accepted: 07/17/2020] [Indexed: 12/13/2022] Open
Abstract
Blocking androgen receptor (AR) transcriptional activity by androgen deprivation therapy (ADT) improves the response to radiotherapy for intermediate and high risk prostate cancer. Unfortunately, ADT, antiandrogens, and abiraterone increase expression of constitutively active splice variants of AR (AR-Vs) which regulate DNA damage repair leading to resistance to radiotherapy. Here we investigate whether blocking the transcriptional activities of full-length AR and AR-Vs with ralaniten leads to enhanced sensitivity to radiotherapy. Combination therapies using ralaniten with ionizing radiation were evaluated for effects on proliferation, colony formation, cell cycle, DNA damage, and Western blot analyses in human prostate cancer cells that express both full-length AR and AR-Vs. Ralaniten and a potent next-generation analog (EPI-7170) decreased expression of DNA repair genes whereas enzalutamide had no effect. FACS analysis revealed a dose-dependent decrease of BrdU incorporation with increased accumulation of γH2AX with a combination of ionizing radiation with ralaniten. An additive inhibitory effect on proliferation of enzalutamide-resistant cells was achieved with a combination of ralaniten compounds with ionizing radiation. Ralaniten and EPI-7170 sensitized prostate cancer cells that express full-length AR and AR-Vs to radiotherapy whereas enzalutamide had no added benefit.
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Affiliation(s)
- Carmen A. Banuelos
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Yusuke Ito
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Jon K. Obst
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Nasrin R. Mawji
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Jun Wang
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Yukiyoshi Hirayama
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Jacky K. Leung
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Teresa Tam
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Amy H. Tien
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
| | - Raymond J. Andersen
- Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada;
| | - Marianne D. Sadar
- Department of Genome Sciences, British Columbia Cancer, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada; (C.A.B.); (Y.I.); (J.K.O.); (N.R.M.); (J.W.); (Y.H.); (J.K.L.); (T.T.); (A.H.T.)
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 1Z7, Canada
- Correspondence: ; Tel.: +604-675-8157; Fax: +604-675-8178
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103
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Blokhina YP, Buchwalter A. Moving fast and breaking things: Incidence and repair of DNA damage within ribosomal DNA repeats. Mutat Res 2020; 821:111715. [PMID: 32717383 DOI: 10.1016/j.mrfmmm.2020.111715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/25/2020] [Accepted: 07/13/2020] [Indexed: 12/31/2022]
Abstract
The genes that code for ribosomal RNA are present in hundreds of tandemly arrayed copies in the human genome. Ribosomal DNA repeats transcribe vast amounts of ribosomal RNA in order to meet the cell's relentless demand for ribosome production. Intrinsic features of ribosomal DNA repeats render them uniquely vulnerable to DNA damage. Sensing and repairing damage to ribosomal DNA involves dramatic spatial reorganization of the nucleolus, the phase-separated nuclear subdomain where ribosomes are made. We highlight recent advances in detecting the incidence of DNA damage and defining the mechanisms of DNA repair on these essential genes.
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Affiliation(s)
- Yana P Blokhina
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, United States
| | - Abigail Buchwalter
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, United States; Department of Physiology, University of California, San Francisco, San Francisco, CA, United States; Chan Zuckerberg Biohub, San Francisco, CA, United States.
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104
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Abstract
Accurate DNA repair and replication are critical for genomic stability and cancer prevention. RAD51 and its gene family are key regulators of DNA fidelity through diverse roles in double-strand break repair, replication stress, and meiosis. RAD51 is an ATPase that forms a nucleoprotein filament on single-stranded DNA. RAD51 has the function of finding and invading homologous DNA sequences to enable accurate and timely DNA repair. Its paralogs, which arose from ancient gene duplications of RAD51, have evolved to regulate and promote RAD51 function. Underscoring its importance, misregulation of RAD51, and its paralogs, is associated with diseases such as cancer and Fanconi anemia. In this review, we focus on the mammalian RAD51 structure and function and highlight the use of model systems to enable mechanistic understanding of RAD51 cellular roles. We also discuss how misregulation of the RAD51 gene family members contributes to disease and consider new approaches to pharmacologically inhibit RAD51.
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Affiliation(s)
- Braulio Bonilla
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA;
| | - Sarah R Hengel
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA;
| | - McKenzie K Grundy
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA;
| | - Kara A Bernstein
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA;
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105
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DNA double-strand break end resection: a critical relay point for determining the pathway of repair and signaling. ACTA ACUST UNITED AC 2020. [DOI: 10.1007/s42764-020-00017-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
AbstractA DNA double-strand break (DSB) is considered the most critical DNA lesion because it causes cell death and severe mutations if it is not repaired or repaired incorrectly. Accumulating evidence has shown that the majority of DSBs are repaired by DNA non-homologous end joining (NHEJ), the first utilized repair pathway in human cells. In contrast, the repair pathway is sometimes diverted into using homologous recombination (HR), which has increased precision under specific circumstances: e.g., when DSBs are generated at transcriptionally active loci or are not readily repaired due to the complexity of damage at the DSB ends or due to highly compacted chromatin. DSB end resection (resection) is considered the most critical turning point for directing repair towards HR. After resection, the HR process is finalized by RAD51 loading and recombination. Thus, understanding the process of resection is critically important to understand the regulation of the choice of DSB repair pathway. In addition, resection is also an important factor influencing DNA damage signaling because unresected ends preferentially activate ATM, whereas longer resected ends activate ATR. Thus, DSB end resection is a key relay point that determines the repair pathway and the signal balance. In this review, we summarize the mechanism underlying DSB end resection and further discuss how it is involved in cancer therapy.
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106
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Gao SS, Guan H, Yan S, Hu S, Song M, Guo ZP, Xie DF, Liu Y, Liu X, Zhang S, Zhou PK. TIP60 K430 SUMOylation attenuates its interaction with DNA-PKcs in S-phase cells: Facilitating homologous recombination and emerging target for cancer therapy. SCIENCE ADVANCES 2020; 6:eaba7822. [PMID: 32832608 PMCID: PMC7439314 DOI: 10.1126/sciadv.aba7822] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 06/01/2020] [Indexed: 05/12/2023]
Abstract
Nonhomologous end joining (NHEJ) and homologous recombination (HR) are major repair pathways of DNA double-strand breaks (DSBs). The pathway choice of HR and NHEJ is tightly regulated in cellular response to DNA damage. Here, we demonstrate that the interaction of TIP60 with DNA-PKcs is attenuated specifically in S phase, which facilitates HR pathway activation. SUMO2 modification of TIP60 K430 mediated by PISA4 E3 ligase blocks its interaction with DNA-PKcs, whereas TIP60 K430R mutation recovers its interaction with DNA-PKcs, which results in abnormally increased phosphorylation of DNA-PKcs S2056 in S phase and marked inhibition of HR efficiency, but barely affects NHEJ activity. TIP60 K430R mutant cancer cells are more sensitive to radiation and PARP inhibitors in cancer cell killing and tumor growth inhibition. Collectively, coordinated regulation of TIP60 and DNA-PKcs facilitates HR pathway choice in S-phase cells. TIP60 K430R mutant is a potential target of radiation and PARPi cancer therapy.
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Affiliation(s)
- Shan-Shan Gao
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
| | - Hua Guan
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
| | - Shuang Yan
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
- Institute for Environmental Medicine and Radiation Hygiene, School of Public Health, University of South China, Hengyang, Hunan Province 421001, P. R. China
| | - Sai Hu
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
| | - Man Song
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
| | - Zong-Pei Guo
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
| | - Da-Fei Xie
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
| | - Yike Liu
- Institute for Chemical Carcinogenesis, State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, P. R. China
| | - Xiaodan Liu
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
| | - Shimeng Zhang
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
| | - Ping-Kun Zhou
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P. R. China
- Institute for Chemical Carcinogenesis, State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Xinzao, Panyu District, Guangzhou 511436, P. R. China
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107
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Li H, Liu ZY, Wu N, Chen YC, Cheng Q, Wang J. PARP inhibitor resistance: the underlying mechanisms and clinical implications. Mol Cancer 2020; 19:107. [PMID: 32563252 PMCID: PMC7305609 DOI: 10.1186/s12943-020-01227-0] [Citation(s) in RCA: 218] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 06/11/2020] [Indexed: 12/31/2022] Open
Abstract
Due to the DNA repair defect, BRCA1/2 deficient tumor cells are more sensitive to PARP inhibitors (PARPi) through the mechanism of synthetic lethality. At present, several PAPRi targeting poly (ADP-ribose) polymerase (PARP) have been approved for ovarian cancer and breast cancer indications. However, PARPi resistance is ubiquitous in clinic. More than 40% BRCA1/2-deficient patients fail to respond to PARPi. In addition, lots of patients acquire PARPi resistance with prolonged oral administration of PARPi. Homologous recombination repair deficient (HRD), as an essential prerequisite of synthetic lethality, plays a vital role in killing tumor cells. Therefore, Homologous recombination repair restoration (HRR) becomes the predominant reason of PARPi resistance. Recently, it was reported that DNA replication fork protection also contributed to PARPi resistance in BRCA1/2-deficient cells and patients. Moreover, various factors, such as reversion mutations, epigenetic modification, restoration of ADP-ribosylation (PARylation) and pharmacological alteration lead to PARPi resistance as well. In this review, we reviewed the underlying mechanisms of PARP inhibitor resistance in detail and summarized the potential strategies to overcome PARPi resistance and increase PARPi sensitivity.
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Affiliation(s)
- He Li
- Hunan Clinical Research Center in Gynecologic Cancer, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283, Tongzipo Road, Changsha, 410013, Hunan, People's Republic of China
| | - Zhao-Yi Liu
- Hunan Clinical Research Center in Gynecologic Cancer, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283, Tongzipo Road, Changsha, 410013, Hunan, People's Republic of China
| | - Nayiyuan Wu
- Hunan Clinical Research Center in Gynecologic Cancer, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283, Tongzipo Road, Changsha, 410013, Hunan, People's Republic of China
| | - Yong-Chang Chen
- Hunan Clinical Research Center in Gynecologic Cancer, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283, Tongzipo Road, Changsha, 410013, Hunan, People's Republic of China
| | - Quan Cheng
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, 410013, Hunan, People's Republic of China
| | - Jing Wang
- Hunan Clinical Research Center in Gynecologic Cancer, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283, Tongzipo Road, Changsha, 410013, Hunan, People's Republic of China. .,Department of Gynecologic Cancer, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283, Tongzipo Road, Changsha, 410013, Hunan, People's Republic of China.
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108
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Hafner A, Reyes J, Stewart-Ornstein J, Tsabar M, Jambhekar A, Lahav G. Quantifying the Central Dogma in the p53 Pathway in Live Single Cells. Cell Syst 2020; 10:495-505.e4. [PMID: 32533938 DOI: 10.1016/j.cels.2020.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 03/08/2020] [Accepted: 05/06/2020] [Indexed: 10/24/2022]
Abstract
Transcription factors (TFs) integrate signals to regulate target gene expression, but we generally lack a quantitative understanding of how changes in TF levels regulate mRNA and protein production. Here, we established a system to simultaneously monitor the levels of p53, a TF that shows oscillations following DNA damage, and the transcription and protein levels of its target p21 in individual cells. p21 transcription tracked p53 dynamics, while p21 protein steadily accumulated. p21 transcriptional activation showed bursts of mRNA production, with p53 levels regulating the probability but not magnitude of activation. Variations in p53 levels between cells contributed to heterogeneous p21 transcription while independent p21 alleles exhibited highly correlated behaviors. Pharmacologically elevating p53 increased the probability of p21 transcription with minor effects on its magnitude, leading to a strong increase in p21 protein levels. Our results reveal quantitative mechanisms by which TF dynamics can regulate protein levels of its targets. A record of this paper's transparent peer review process is included in the Supplemental Information.
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Affiliation(s)
- Antonina Hafner
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - José Reyes
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | | | - Michael Tsabar
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA; Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Ashwini Jambhekar
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Galit Lahav
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA.
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109
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Maurissen TL, Woltjen K. Synergistic gene editing in human iPS cells via cell cycle and DNA repair modulation. Nat Commun 2020; 11:2876. [PMID: 32513994 PMCID: PMC7280248 DOI: 10.1038/s41467-020-16643-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/13/2020] [Indexed: 01/08/2023] Open
Abstract
Precise gene editing aims at generating single-nucleotide modifications to correct or model human disease. However, precision editing with nucleases such as CRIPSR-Cas9 has seen limited success due to poor efficiency and limited practicality. Here, we establish a fluorescent DNA repair assay in human induced pluripotent stem (iPS) cells to visualize and quantify the frequency of DNA repair outcomes during monoallelic and biallelic targeting. We found that modulating both DNA repair and cell cycle phase via defined culture conditions and small molecules synergistically enhanced the frequency of homology-directed repair (HDR). Notably, targeting in homozygous reporter cells results in high levels of editing with a vast majority of biallelic HDR outcomes. We then leverage efficient biallelic HDR with mixed ssODN repair templates to generate heterozygous mutations. Synergistic gene editing represents an effective strategy to generate precise genetic modifications in human iPS cells. Precision editing with CRISPR-Cas9 often suffers from poor efficiency. Here the authors identify culture conditions and small molecules that synergize to promote homology-directed repair (HDR) in induced pluripotent stem (iPS) cells.
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Affiliation(s)
- Thomas L Maurissen
- Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan.,Department of Life Science Frontiers, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, 606-8507, Japan
| | - Knut Woltjen
- Department of Life Science Frontiers, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, 606-8507, Japan.
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110
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Abstract
The fermentation industry is known to be very conservative, relying on traditional yeast management. Yet, in the modern fast-paced world, change comes about in facets such as climate change altering the quality and quantity of harvests, changes due to government regulations e.g., the use of pesticides or SO2, the need to become more sustainable, and of course by changes in consumer preferences. As a silent companion of the fermentation industry, the wine yeast Saccharomyces cerevisiae has followed mankind through millennia, changing from a Kulturfolger, into a domesticated species for the production of bread, beer, and wine and further on into a platform strain for the production of biofuels, enzymes, flavors, or pharmaceuticals. This success story is based on the ‘awesome power of yeast genetics’. Central to this is the very efficient homologous recombination (HR) machinery of S. cerevisiae that allows highly-specific genome edits. This microsurgery tool is so reliable that yeast has put a generally recognized as safe (GRAS) label onto itself and entrusted to itself the life-changing decision of mating type-switching. Later, yeast became its own genome editor, interpreted as domestication events, to adapt to harsh fermentation conditions. In biotechnology, yeast HR has been used with tremendous success over the last 40 years. Here we discuss several types of yeast genome edits then focus on HR and its inherent potential for evolving novel wine yeast strains and styles relevant for changing markets.
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111
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Gonzalez-Rajal A, Hastings JF, Watkins DN, Croucher DR, Burgess A. Breathing New Life into the Mechanisms of Platinum Resistance in Lung Adenocarcinoma. Front Cell Dev Biol 2020; 8:305. [PMID: 32457904 PMCID: PMC7225257 DOI: 10.3389/fcell.2020.00305] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 04/07/2020] [Indexed: 12/25/2022] Open
Affiliation(s)
| | - Jordan F Hastings
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Sydney, NSW, Australia
| | - D Neil Watkins
- Research Institute in Oncology and Hematology, Cancer Care Manitoba, Winnipeg, MB, Canada.,Department of Internal Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - David R Croucher
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Sydney, NSW, Australia.,St Vincent's Hospital Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Andrew Burgess
- ANZAC Research Institute, Concord, NSW, Australia.,The University of Sydney Concord Clinical School, Faculty of Medicine and Health, Sydney, NSW, Australia
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112
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Machín F, Ayra-Plasencia J. Are Anaphase Events Really Irreversible? The Endmost Stages of Cell Division and the Paradox of the DNA Double-Strand Break Repair. Bioessays 2020; 42:e2000021. [PMID: 32363600 DOI: 10.1002/bies.202000021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/16/2020] [Indexed: 12/25/2022]
Abstract
It has been recently demonstrated that yeast cells are able to partially regress chromosome segregation in telophase as a response to DNA double-strand breaks (DSBs), likely to find a donor sequence for homology-directed repair (HDR). This regression challenges the traditional concept that establishes anaphase events as irreversible, hence opening a new field of research in cell biology. Here, the nature of this new behavior in yeast is summarized and the underlying mechanisms are speculated about. It is also discussed whether it can be reproduced in other eukaryotes. Overall, this work brings forwards the need of understanding how cells attempt to repair DSBs when transiting the latest stages of mitosis, i.e., anaphase and telophase.
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Affiliation(s)
- Félix Machín
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, 38010, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna, Santa Cruz de Tenerife, 38200, Spain.,Universidad Fernando Pessoa Canarias, Las Palmas de Gran Canaria, 35450, Spain
| | - Jessel Ayra-Plasencia
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, 38010, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna, Santa Cruz de Tenerife, 38200, Spain
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113
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Abstract
The successful use of PARP1 inhibitors like olaparib (Loparza®) in the treatment of BRCA1/2- deficient breast cancer has provided clinical proof of concept for applying personalized medicine based on synthetic lethality to the treatment of cancer. Unfortunately, all marketed PARP1 inhibitors act by competing with the cofactor NAD+ and resistance is already developing to this anti-cancer mechanism. Allosteric PARP1 inhibitors could provide a means of overcoming this resistance. A high throughput screen performed by Tulin et al. identified 5F02 as an allosteric PARP inhibitor that acts by preventing the enzymatic activation of PARP1 by histone H4. 5F02 demonstrated anti-cancer activity in several cancer cell lines and was more potent than olaparib and synergistic with olaparib in these assays. In the present study we explored the structure-activity relationship of 5F02 by preparing analogs that possessed structural variation in four regions of the chemical scaffold. Our efforts led to lead molecule 7, which demonstrated potent anti-clonogenic activity against BRCA-deficient NALM6 leukemia cells in culture and a therapeutic index for the BRCA-deficient cells over their BRCA-proficient isogenic counterparts.
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114
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Structural biology of multicomponent assemblies in DNA double-strand-break repair through non-homologous end joining. Curr Opin Struct Biol 2020; 61:9-16. [DOI: 10.1016/j.sbi.2019.09.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 09/30/2019] [Indexed: 01/19/2023]
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115
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Blackford AN, Stucki M. How Cells Respond to DNA Breaks in Mitosis. Trends Biochem Sci 2020; 45:321-331. [PMID: 32001093 DOI: 10.1016/j.tibs.2019.12.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/05/2019] [Accepted: 12/31/2019] [Indexed: 12/16/2022]
Abstract
DNA double-strand breaks (DSBs) are highly toxic lesions that can lead to chromosomal instability if they are not repaired correctly. DSBs are especially dangerous in mitosis when cells go through the complex process of equal chromosome segregation into daughter cells. When cells encounter DSBs in interphase, they are able to arrest the cell cycle until the breaks are repaired before entering mitosis. However, when DSBs occur during mitosis, cells no longer arrest but prioritize completion of cell division over repair of DNA damage. This review focuses on recent progress in our understanding of the mechanisms that allow mitotic cells to postpone DSB repair without accumulating massive chromosomal instability. Additionally, we review possible physiological consequences of failed DSB responses in mitosis.
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Affiliation(s)
- Andrew N Blackford
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK; Cancer Research UK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK.
| | - Manuel Stucki
- Department of Gynecology, University of Zurich, Wagistrasse 14, CH-8952 Schlieren, Switzerland.
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116
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Current Understanding of RAD52 Functions: Fundamental and Therapeutic Insights. Cancers (Basel) 2020; 12:cancers12030705. [PMID: 32192055 PMCID: PMC7140074 DOI: 10.3390/cancers12030705] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 03/13/2020] [Indexed: 02/07/2023] Open
Abstract
In this Special Issue, we would like to focus on the various functions of the RAD52 helicase-like protein and the current implications of such findings for cancer treatment. Over the last few years, various laboratories have discovered particular activities of mammalian RAD52—both in S and M phase—that are distinct from the auxiliary role of yeast RAD52 in homologous recombination. At DNA double-strand breaks, RAD52 was demonstrated to spur alternative pathways to compensate for the loss of homologous recombination functions. At collapsed replication forks, RAD52 activates break-induced replication. In the M phase, RAD52 promotes the finalization of DNA replication. Its compensatory role in the resolution of DNA double-strand breaks has put RAD52 in the focus of synthetic lethal strategies, which is particularly relevant for cancer treatment.
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117
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Swartjes T, Staals RH, van der Oost J. Editor's cut: DNA cleavage by CRISPR RNA-guided nucleases Cas9 and Cas12a. Biochem Soc Trans 2020; 48:207-219. [PMID: 31872209 PMCID: PMC7054755 DOI: 10.1042/bst20190563] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 12/05/2019] [Accepted: 12/06/2019] [Indexed: 12/26/2022]
Abstract
Discovered as an adaptive immune system of prokaryotes, CRISPR-Cas provides many promising applications. DNA-cleaving Cas enzymes like Cas9 and Cas12a, are of great interest for genome editing. The specificity of these DNA nucleases is determined by RNA guides, providing great targeting adaptability. Besides this general method of programmable DNA cleavage, these nucleases have different biochemical characteristics, that can be exploited for different applications. Although Cas nucleases are highly promising, some room for improvement remains. New developments and discoveries like base editing, prime editing, and CRISPR-associated transposons might address some of these challenges.
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Affiliation(s)
- Thomas Swartjes
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, Netherlands
| | - Raymond H.J. Staals
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, Netherlands
| | - John van der Oost
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, Netherlands
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118
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Soni A, Murmann-Konda T, Siemann-Loekes M, Pantelias GE, Iliakis G. Chromosome breaks generated by low doses of ionizing radiation in G 2-phase are processed exclusively by gene conversion. DNA Repair (Amst) 2020; 89:102828. [PMID: 32143127 DOI: 10.1016/j.dnarep.2020.102828] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/31/2020] [Accepted: 02/21/2020] [Indexed: 02/07/2023]
Abstract
Four repair pathways process DNA double-strand breaks (DSBs). Among these pathways the homologous recombination repair (HRR) subpathway of gene conversion (GC) affords error-free processing, but functions only in S- and G2-phases of the cell cycle. Classical non-homologous end-joining (c-NHEJ) operates throughout the cell cycle, but causes small deletions and translocations. Similar deficiencies in exaggerated form, combined with reduced efficiency, are associated with alternative end-joining (alt-EJ). Finally, single-strand annealing (SSA) causes large deletions and possibly translocations. Thus, processing of a DSB by any pathway, except GC, poses significant risks to the genome, making the mechanisms navigating pathway-engagement critical to genome stability. Logically, the cell ought to attempt engagement of the pathway ensuring preservation of the genome, while accommodating necessities generated by the types of DSBs induced. Thereby, inception of DNA end-resection will be key determinant for GC, SSA and alt-EJ engagement. We reported that during G2-phase, where all pathways are active, GC engages in the processing of almost 50 % of DSBs, at low DSB-loads in the genome, and that this contribution rapidly drops to nearly zero with increasing DSB-loads. At the transition between these two extremes, SSA and alt-EJ compensate, but at extremely high DSB-loads resection-dependent pathways are suppressed and c-NHEJ remains mainly active. We inquired whether in this processing framework all DSBs have similar fates. Here, we analyze in G2-phase the processing of a subset of DSBs defined by their ability to break chromosomes. Our results reveal an absolute requirement for GC in the processing of chromatid breaks at doses in the range of 1 Gy. Defects in c-NHEJ delay significantly the inception of processing by GC, but leave processing kinetics unchanged. These results delineate the essential role of GC in chromatid break repair before mitosis and classify DSBs that underpin this breakage as the exclusive substrate of GC.
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Affiliation(s)
- Aashish Soni
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, Essen, Germany
| | - Tamara Murmann-Konda
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, Essen, Germany
| | - Maria Siemann-Loekes
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, Essen, Germany
| | - Gabriel E Pantelias
- Institute of Nuclear Technology and Radiation Protection, National Centre for Scientific Research "Demokritos,''Aghia Paraskevi Attikis, Athens, Greece
| | - George Iliakis
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, Essen, Germany.
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119
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Abad E, Graifer D, Lyakhovich A. DNA damage response and resistance of cancer stem cells. Cancer Lett 2020; 474:106-117. [PMID: 31968219 DOI: 10.1016/j.canlet.2020.01.008] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/09/2020] [Accepted: 01/13/2020] [Indexed: 12/20/2022]
Abstract
The cancer stem cell (CSC) model defines tumors as hierarchically organized entities, containing a small population of tumorigenic CSC, or tumour-initiating cells, placed at the apex of this hierarchy. These cells may share common qualities with chemo- and radio-resistant cancer cells and contribute to self-renewal activities resulting in tumour formation, maintenance, growth and metastasis. Yet, it remains obscure what self-defense mechanisms are utilized by these cells against the chemotherapeutic drugs or radiotherapy. Recently, attention has been focused on the pivotal role of the DNA damage response (DDR) in tumorigenesis. In line with this note, an increased DDR that prevents CSC and chemoresistant cells from genotoxic pressure of chemotherapeutic drugs or radiation may be responsible for cancer metastasis. In this review, we focus on the current knowledge concerning the role of DDR in CSC and resistant cancer cells and describe the existing opportunities of re-sensitizing such cells to modulate therapeutic treatment effects.
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Affiliation(s)
- Etna Abad
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | | | - Alex Lyakhovich
- Institute of Molecular Biology and Biophysics, Federal Research Center of Fundamental and Translational Medicine, Novosibirsk, Russia; Vall D'Hebron Institut de Recerca, 08035, Barcelona, Spain.
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120
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Meyer F, Becker S, Classen S, Parplys AC, Mansour WY, Riepen B, Timm S, Ruebe C, Jasin M, Wikman H, Petersen C, Rothkamm K, Borgmann K. Prevention of DNA Replication Stress by CHK1 Leads to Chemoresistance Despite a DNA Repair Defect in Homologous Recombination in Breast Cancer. Cells 2020; 9:cells9010238. [PMID: 31963582 PMCID: PMC7017274 DOI: 10.3390/cells9010238] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/03/2020] [Accepted: 01/14/2020] [Indexed: 01/20/2023] Open
Abstract
Chromosomal instability not only has a negative effect on survival in triple-negative breast cancer, but also on the well treatable subgroup of luminal A tumors. This suggests a general mechanism independent of subtypes. Increased chromosomal instability (CIN) in triple-negative breast cancer (TNBC) is attributed to a defect in the DNA repair pathway homologous recombination. Homologous recombination (HR) prevents genomic instability by repair and protection of replication. It is unclear whether genetic alterations actually lead to a repair defect or whether superior signaling pathways are of greater importance. Previous studies focused exclusively on the repair function of HR. Here, we show that the regulation of HR by the intra-S-phase damage response at the replication is of overriding importance. A damage response activated by Ataxia telangiectasia and Rad3 related-checkpoint kinase 1 (ATR-CHK1) can prevent replication stress and leads to resistance formation. CHK1 thus has a preferred role over HR in preventing replication stress in TNBC. The signaling cascade ATR-CHK1 can compensate for a double-strand break repair error and lead to resistance of HR-deficient tumors. Established methods for the identification of HR-deficient tumors for Poly(ADP-Ribose)-Polymerase 1 (PARP1) inhibitor therapies should be extended to include analysis of candidates for intra-S phase damage response.
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Affiliation(s)
- Felix Meyer
- Laboratory of Radiobiology and Experimental Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (F.M.); (S.B.); (S.C.); (A.C.P.); (W.Y.M.); (B.R.); (K.R.)
| | - Saskia Becker
- Laboratory of Radiobiology and Experimental Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (F.M.); (S.B.); (S.C.); (A.C.P.); (W.Y.M.); (B.R.); (K.R.)
| | - Sandra Classen
- Laboratory of Radiobiology and Experimental Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (F.M.); (S.B.); (S.C.); (A.C.P.); (W.Y.M.); (B.R.); (K.R.)
| | - Ann Christin Parplys
- Laboratory of Radiobiology and Experimental Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (F.M.); (S.B.); (S.C.); (A.C.P.); (W.Y.M.); (B.R.); (K.R.)
| | - Wael Yassin Mansour
- Laboratory of Radiobiology and Experimental Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (F.M.); (S.B.); (S.C.); (A.C.P.); (W.Y.M.); (B.R.); (K.R.)
- Tumor Biology Department, National Cancer Institute, Cairo University, Cairo 11796, Egypt
| | - Britta Riepen
- Laboratory of Radiobiology and Experimental Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (F.M.); (S.B.); (S.C.); (A.C.P.); (W.Y.M.); (B.R.); (K.R.)
| | - Sara Timm
- Department of Radiation Oncology, Saarland University, 66421 Hamburg/Saar, Germany; (S.T.); (C.R.)
| | - Claudia Ruebe
- Department of Radiation Oncology, Saarland University, 66421 Hamburg/Saar, Germany; (S.T.); (C.R.)
| | - Maria Jasin
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA;
| | - Harriet Wikman
- Department of Tumor Biology, University Center Hamburg-Eppendorf, 20246 Hamburg, Germany;
| | - Cordula Petersen
- Department of Radiotherapy and Radiooncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany;
| | - Kai Rothkamm
- Laboratory of Radiobiology and Experimental Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (F.M.); (S.B.); (S.C.); (A.C.P.); (W.Y.M.); (B.R.); (K.R.)
| | - Kerstin Borgmann
- Laboratory of Radiobiology and Experimental Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (F.M.); (S.B.); (S.C.); (A.C.P.); (W.Y.M.); (B.R.); (K.R.)
- Correspondence: ; Tel.: +49-40-74105-3596
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121
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Mohseni-Salehi FS, Zare-Mirakabad F, Sadeghi M, Ghafouri-Fard S. A Stochastic Model of DNA Double-Strand Breaks Repair Throughout the Cell Cycle. Bull Math Biol 2020; 82:11. [PMID: 31933029 DOI: 10.1007/s11538-019-00692-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 12/20/2019] [Indexed: 01/15/2023]
Abstract
Cell cycle phase is a decisive factor in determining the repair pathway of DNA double-strand breaks (DSBs) by non-homologous end joining (NHEJ) or homologous recombination (HR). Recent experimental studies revealed that 53BP1 and BRCA1 are the key mediators of the DNA damage response (DDR) with antagonizing roles in choosing the appropriate DSB repair pathway in G1, S, and G2 phases. Here, we present a stochastic model of biochemical kinetics involved in detecting and repairing DNA DSBs induced by ionizing radiation during the cell cycle progression. A three-dimensional stochastic process is defined to monitor the cell cycle phase and DSBs repair at times after irradiation. To estimate the model parameters, a Metropolis Monte Carlo method is applied to perform maximum likelihood estimation utilizing the kinetics of γ-H2AX and RAD51 foci formation in G1, S, and G2 phases. The recruitment of DSB repair proteins is verified by comparing our model predictions with the corresponding experimental data on human cells after exposure to X and γ-radiation. Furthermore, the interaction between 53BP1 and BRCA1 is simulated for G1 and S/G2 phases determining the competition between NHEJ and HR pathways in repairing induced DSBs throughout the cell cycle. In accordance with recent biological data, the numerical results demonstrate that the maximum proportion of HR occurs in S phase cells and the high level of NHEJ takes place in G1 and G2 phases. Moreover, the stochastic realizations of the total yield of simple and complex DSBs ligation are compared for G1 and S/G2 damaged cells. Finally, the proposed stochastic model is validated when DSBs induced by different particle radiation such as iron, silicon, oxygen, proton, and carbon.
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Affiliation(s)
- Fazeleh S Mohseni-Salehi
- Mathematics and Computer Science Department, Amirkabir University of Technology (Tehran Polytechinc), Tehran, Iran
| | - Fatemeh Zare-Mirakabad
- Mathematics and Computer Science Department, Amirkabir University of Technology (Tehran Polytechinc), Tehran, Iran.
| | - Mehdi Sadeghi
- School of Biological Science, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
- National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
| | - Soudeh Ghafouri-Fard
- Department of Medical Genetics, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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122
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March OP, Kocher T, Koller U. Context-Dependent Strategies for Enhanced Genome Editing of Genodermatoses. Cells 2020; 9:E112. [PMID: 31906492 PMCID: PMC7016731 DOI: 10.3390/cells9010112] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 12/27/2019] [Accepted: 12/31/2019] [Indexed: 12/17/2022] Open
Abstract
The skin provides direct protection to the human body from assault by the harsh external environment. The crucial function of this organ is significantly disrupted in genodermatoses patients. Genodermatoses comprise a heterogeneous group of largely monogenetic skin disorders, typically involving mutations in genes encoding structural proteins. Therapeutic options for this debilitating group of diseases, including epidermolysis bullosa, primarily consist of wound management. Genome editing approaches co-opt double-strand break repair pathways to introduce desired sequence alterations at specific loci. Rapid advances in genome editing technologies have the potential to propel novel genetic therapies into the clinic. However, the associated phenotypes of many mutations may be treated via several genome editing strategies. Therefore, for potential clinical applications, implementation of efficient approaches based upon mutation, gene and disease context is necessary. Here, we describe current genome editing approaches for the treatment of genodermatoses, along with a discussion of the optimal strategy for each genetic context, in order to achieve enhanced genome editing approaches.
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Affiliation(s)
| | | | - Ulrich Koller
- EB House Austria, Research Program for Molecular Therapy of Genodermatoses, Department of Dermatology and Allergology, University Hospital of the Paracelsus Medical University Salzburg, 5020 Salzburg, Austria; (O.P.M.); (T.K.)
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123
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Wang Z, Zuo W, Zeng Q, Li Y, Lu T, Bu Y, Hu G. The Homologous Recombination Repair Pathway is Associated with Resistance to Radiotherapy in Nasopharyngeal Carcinoma. Int J Biol Sci 2020; 16:408-419. [PMID: 32015678 PMCID: PMC6990897 DOI: 10.7150/ijbs.37302] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 11/15/2019] [Indexed: 12/15/2022] Open
Abstract
Radiotherapy plays a major role in the management of nasopharyngeal carcinoma (NPC). However, the radioresistant cells limit its efficiency and drive recurrence inside the irradiated tumor volume leading to poor outcome for patients. To illuminate the signal pathway involved in the radioresistance and evaluate the potential for predicting NPC response to radiotherapy, we established the radioresistant NPC cell line (CNE2-RR) derived from NPC cell line CNE2 by gradually increased the radiation dose (total 60 Gy), and the radioresistance of CNE2-RR cells was evaluated by the colony formation, FCM and comet assays. Furthermore, comparison of established CNE2-RR cell line to parental cell line found the homologous recombination repair (HRR) proteins differences involved in NPC radioresistance. In addition, the differentially expressed proteins were further validated by western blotting, immunofluorescence and IHC in tumor xenografs and radioresistant NPC tissues. Furthermore, the correlation of HRR proteins expression levels with NPC radioresistance were evaluated. The results showed that the upregulation of HRR proteins were significantly correlated with NPC radioresistance. In addition, using the Youden Index cutoff value, a panel of the HRR proteins analyses revealed a sensitivity of 70%, specificity of 72%. Furthermore, silencing NFBD1 enhanced the radiosensitivity of CNE2-RR cells by impairing IR-inducing γ-H2AX and HR proteins foci formation. These results suggest that controlling the HRR signaling pathway may hold promise to overcome NPC radioresistance.
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Affiliation(s)
- Zhihai Wang
- Department of Otorhinolaryngology, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Wenqi Zuo
- Department of Otorhinolaryngology, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Quan Zeng
- Department of Otorhinolaryngology, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Yanshi Li
- Department of Otorhinolaryngology, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Tao Lu
- Department of Otorhinolaryngology, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Youquan Bu
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing, 400016, China
| | - Guohua Hu
- Department of Otorhinolaryngology, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
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124
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Duskova K, Lejault P, Benchimol É, Guillot R, Britton S, Granzhan A, Monchaud D. DNA Junction Ligands Trigger DNA Damage and Are Synthetic Lethal with DNA Repair Inhibitors in Cancer Cells. J Am Chem Soc 2019; 142:424-435. [PMID: 31833764 DOI: 10.1021/jacs.9b11150] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Translocation of DNA and RNA polymerases along their duplex substrates results in DNA supercoiling. This torsional stress promotes the formation of plectonemic structures, including three-way DNA junction (TWJ), which can block DNA transactions and lead to DNA damage. While cells have evolved multiple mechanisms to prevent the accumulation of such structures, stabilizing TWJ through ad hoc ligands offer an opportunity to trigger DNA damage in cells with high levels of transcription and replication, such as cancer cells. Here, we develop a series of azacryptand-based TWJ ligands, we thoroughly characterize their TWJ-interacting properties in vitro and demonstrate their capacity to trigger DNA damage in rapidly dividing human cancer cells. We also demonstrate that TWJ ligands are amenable to chemically induced synthetic lethality strategies upon association with inhibitors of DNA repair, thus paving the way toward innovative drug combinations to fight cancers.
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Affiliation(s)
- Katerina Duskova
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), CNRS UMR 6302 , UBFC Dijon , 21078 Dijon , France
| | - Pauline Lejault
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), CNRS UMR 6302 , UBFC Dijon , 21078 Dijon , France
| | - Élie Benchimol
- Institut Curie, CNRS UMR 9187, INSERM U1196 , PSL Research University , 91405 Orsay , France.,Université Paris Saclay, CNRS UMR 9187, INSERM U1196 , Université Paris-Sud , 91405 Orsay , France
| | - Régis Guillot
- Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), CNRS UMR 8182, Université Paris-Sud , Université Paris Saclay , 91405 Orsay , France
| | - Sébastien Britton
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS UMR 5089, Université de Toulouse , UPS , Equipe labellisée la Ligue Contre le Cancer , 31077 Toulouse , France
| | - Anton Granzhan
- Institut Curie, CNRS UMR 9187, INSERM U1196 , PSL Research University , 91405 Orsay , France.,Université Paris Saclay, CNRS UMR 9187, INSERM U1196 , Université Paris-Sud , 91405 Orsay , France
| | - David Monchaud
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), CNRS UMR 6302 , UBFC Dijon , 21078 Dijon , France
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125
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Stinson BM, Moreno AT, Walter JC, Loparo JJ. A Mechanism to Minimize Errors during Non-homologous End Joining. Mol Cell 2019; 77:1080-1091.e8. [PMID: 31862156 DOI: 10.1016/j.molcel.2019.11.018] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 10/09/2019] [Accepted: 11/22/2019] [Indexed: 01/15/2023]
Abstract
Enzymatic processing of DNA underlies all DNA repair, yet inappropriate DNA processing must be avoided. In vertebrates, double-strand breaks are repaired predominantly by non-homologous end joining (NHEJ), which directly ligates DNA ends. NHEJ has the potential to be highly mutagenic because it uses DNA polymerases, nucleases, and other enzymes that modify incompatible DNA ends to allow their ligation. Using frog egg extracts that recapitulate NHEJ, we show that end processing requires the formation of a "short-range synaptic complex" in which DNA ends are closely aligned in a ligation-competent state. Furthermore, single-molecule imaging directly demonstrates that processing occurs within the short-range complex. This confinement of end processing to a ligation-competent complex ensures that DNA ends undergo ligation as soon as they become compatible, thereby minimizing mutagenesis. Our results illustrate how the coordination of enzymatic catalysis with higher-order structural organization of substrate maximizes the fidelity of DNA repair.
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Affiliation(s)
- Benjamin M Stinson
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Andrew T Moreno
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Johannes C Walter
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Boston, MA 02115, USA.
| | - Joseph J Loparo
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
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126
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The effect of inhibitors of phosphatidylinositol 3-kinase-related kinases on dibenzo[def,p]chrysene genotoxicity measured by γH2AX levels and neutral comet assay in HepG2 human hepatocellular cancer cells. Toxicol In Vitro 2019; 63:104749. [PMID: 31838185 DOI: 10.1016/j.tiv.2019.104749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 12/11/2019] [Accepted: 12/11/2019] [Indexed: 12/12/2022]
Abstract
In the study the modulating effect of inhibition of phosphatidylinositol 3-kinase-related kinases (PIKK): ATM (Ataxia Telangiectasia Mutated), ATR (Ataxia Telangiectasia and Rad3 Related) and DNA-PK (DNA-dependent protein kinase) on genotoxicity of dibenzo[def,p]chrysene (DBC) in HepG2 human hepatocellular cancer cells was investigated. The cytotoxicity of DBC was determined, also in combination with PIKK inhibitors, using the MTT reduction assay. The high cytotoxicity of DBC was observed after 72 h incubation (IC50 = 0.06 μM). The PIKK inhibitors applied at non-cytotoxic concentrations: caffeine (1 mM) and KU55933 (2.5 μM) had no significant influence on the DBC cytotoxicity, however NU7026 (5 μM) caused significant increase in the cell viability by about 25%. The combinations of the inhibitors (double or triple) where NU7026 was present also caused increase in the cell viability (i.e. cytoprotective effect) compared to the effect of DBC. The level of damage to the genetic material (DNA double strand breaks, DSB) was assessed by measuring levels of phosphorylated form of H2A histone (γH2AX) and neutral comet assay. DBC induced DSB in a concentration and time-dependent manner. NU7026 considerably reduced the level of DSB level measured by γH2AX and comet assay. The obtained results confirm that DBC is cytotoxic and causes damage to the genetic material including DSB. The DNA-PK inhibitor NU7026 increases cell viability after exposure to DBC and reduces DNA damage, what indicates an important role of the sensor kinase in mediating the effect.
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127
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Gómez-Herreros F. DNA Double Strand Breaks and Chromosomal Translocations Induced by DNA Topoisomerase II. Front Mol Biosci 2019; 6:141. [PMID: 31921889 PMCID: PMC6915882 DOI: 10.3389/fmolb.2019.00141] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/19/2019] [Indexed: 01/03/2023] Open
Abstract
DNA double strand breaks (DSBs) are the most cytotoxic lesions of those occurring in the DNA and can lead to cell death or result in genome mutagenesis and chromosomal translocations. Although most of these rearrangements have detrimental effects for cellular survival, single events can provide clonal advantage and result in abnormal cellular proliferation and cancer. The origin and the environment of the DNA break or the repair pathway are key factors that influence the frequency at which these events appear. However, the molecular mechanisms that underlie the formation of chromosomal translocations remain unclear. DNA topoisomerases are essential enzymes present in all cellular organisms with critical roles in DNA metabolism and that have been linked to the formation of deleterious DSBs for a long time. DSBs induced by the abortive activity of DNA topoisomerase II (TOP2) are “trending topic” because of their possible role in genome instability and oncogenesis. Furthermore, transcription associated TOP2 activity appears to be one of the most determining causes behind the formation of chromosomal translocations. In this review, the origin of recombinogenic TOP2 breaks and the determinants behind their tendency to translocate will be summarized.
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Affiliation(s)
- Fernando Gómez-Herreros
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Virgen del Rocío-CSIC-Universidad de Sevilla, Seville, Spain.,Departamento de Genética, Universidad de Sevilla, Seville, Spain
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128
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Structural and Dynamical Signatures of Local DNA Damage in Live Cells. Biophys J 2019; 118:2168-2180. [PMID: 31818467 DOI: 10.1016/j.bpj.2019.10.042] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 09/12/2019] [Accepted: 10/15/2019] [Indexed: 02/06/2023] Open
Abstract
The dynamic organization of chromatin inside the cell nucleus plays a key role in gene regulation and genome replication, as well as maintaining genome integrity. Although the static folded state of the genome has been extensively studied, dynamical signatures of processes such as transcription or DNA repair remain an open question. Here, we investigate the interphase chromatin dynamics in human cells in response to local DNA damage, specifically, DNA double-strand breaks (DSBs). Using simultaneous two-color spinning-disk confocal microscopy, we monitor the DSB dynamics and the compaction of the surrounding chromatin, visualized by fluorescently labeled 53BP1 and histone H2B, respectively. Our study reveals a surprising difference between the mobility of DSBs located in the nuclear interior versus periphery (less than 1 μm from the nuclear envelope), with the interior DSBs being almost twice as mobile as the periphery DSBs. Remarkably, we find that the DSB sites possess a robust structural signature in a form of a unique chromatin compaction profile. Moreover, our data show that the DSB motion is subdiffusive and ATP-dependent and exhibits unique dynamical signatures, different from those of undamaged chromatin. Our findings reveal that the DSB mobility follows a universal relationship defined solely by the physical parameters describing the DSBs and their local environment, such as the DSB focus size (represented by the local accumulation of 53BP1), DSB density, and the local chromatin compaction. This suggests that the DSB-related repair processes are robust and likely deterministic because the observed dynamical signatures (DSB mobility) can be explained solely by their structural features (DSB focus size, local chromatin compaction). Such knowledge might help in detecting local DNA damage in live cells, as well as in aiding our biophysical understanding of genome integrity in health and disease.
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129
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Toma M, Sullivan-Reed K, Śliwiński T, Skorski T. RAD52 as a Potential Target for Synthetic Lethality-Based Anticancer Therapies. Cancers (Basel) 2019; 11:E1561. [PMID: 31615159 PMCID: PMC6827130 DOI: 10.3390/cancers11101561] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/11/2019] [Accepted: 10/11/2019] [Indexed: 12/15/2022] Open
Abstract
Alterations in DNA repair systems play a key role in the induction and progression of cancer. Tumor-specific defects in DNA repair mechanisms and activation of alternative repair routes create the opportunity to employ a phenomenon called "synthetic lethality" to eliminate cancer cells. Targeting the backup pathways may amplify endogenous and drug-induced DNA damage and lead to specific eradication of cancer cells. So far, the synthetic lethal interaction between BRCA1/2 and PARP1 has been successfully applied as an anticancer treatment. Although PARP1 constitutes a promising target in the treatment of tumors harboring deficiencies in BRCA1/2-mediated homologous recombination (HR), some tumor cells survive, resulting in disease relapse. It has been suggested that alternative RAD52-mediated HR can protect BRCA1/2-deficient cells from the accumulation of DNA damage and the synthetic lethal effect of PARPi. Thus, simultaneous inhibition of RAD52 and PARP1 might result in a robust dual synthetic lethality, effectively eradicating BRCA1/2-deficient tumor cells. In this review, we will discuss the role of RAD52 and its potential application in synthetic lethality-based anticancer therapies.
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Affiliation(s)
- Monika Toma
- Sol Sherry Thrombosis Research Center and Fels Institute for Cancer Research and Molecular Biology Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA.
- Laboratory of Medical Genetics Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland.
| | - Katherine Sullivan-Reed
- Sol Sherry Thrombosis Research Center and Fels Institute for Cancer Research and Molecular Biology Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA.
| | - Tomasz Śliwiński
- Laboratory of Medical Genetics Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland.
| | - Tomasz Skorski
- Sol Sherry Thrombosis Research Center and Fels Institute for Cancer Research and Molecular Biology Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA.
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130
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Barroso-González J, García-Expósito L, Hoang SM, Lynskey ML, Roncaioli JL, Ghosh A, Wallace CT, de Vitis M, Modesti M, Bernstein KA, Sarkar SN, Watkins SC, O'Sullivan RJ. RAD51AP1 Is an Essential Mediator of Alternative Lengthening of Telomeres. Mol Cell 2019; 76:11-26.e7. [PMID: 31400850 PMCID: PMC6778027 DOI: 10.1016/j.molcel.2019.06.043] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 05/23/2019] [Accepted: 06/26/2019] [Indexed: 12/17/2022]
Abstract
Alternative lengthening of telomeres (ALT) is a homology-directed repair (HDR) mechanism of telomere elongation that controls proliferation in aggressive cancers. We show that the disruption of RAD51-associated protein 1 (RAD51AP1) in ALT+ cancer cells leads to generational telomere shortening. This is due to RAD51AP1's involvement in RAD51-dependent homologous recombination (HR) and RAD52-POLD3-dependent break induced DNA synthesis. RAD51AP1 KO ALT+ cells exhibit telomere dysfunction and cytosolic telomeric DNA fragments that are sensed by cGAS. Intriguingly, they activate ULK1-ATG7-dependent autophagy as a survival mechanism to mitigate DNA damage and apoptosis. Importantly, RAD51AP1 protein levels are elevated in ALT+ cells due to MMS21 associated SUMOylation. Mutation of a single SUMO-targeted lysine residue perturbs telomere dynamics. These findings indicate that RAD51AP1 is an essential mediator of the ALT mechanism and is co-opted by post-translational mechanisms to maintain telomere length and ensure proliferation of ALT+ cancer cells.
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Affiliation(s)
- Jonathan Barroso-González
- Department of Pharmacology and Chemical Biology, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Laura García-Expósito
- Department of Pharmacology and Chemical Biology, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Song My Hoang
- Department of Pharmacology and Chemical Biology, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Michelle L Lynskey
- Department of Pharmacology and Chemical Biology, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Justin L Roncaioli
- Department of Pharmacology and Chemical Biology, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Arundhati Ghosh
- Department of Microbiology and Molecular Genetics, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Callen T Wallace
- Department of Cell Biology, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Marco de Vitis
- Department of Science, University of Rome "ROMA TRE", 00146 Rome, Italy
| | - Mauro Modesti
- Cancer Research Center of Marseille, CNRS UMR7258, Inserm UMR1068, Aix Marseille Université U105; Institut Paoli Calmettes, 27 Boulevard Lei Roure CS30059, 13273 Marseille, Cedex 09, France
| | - Kara A Bernstein
- Department of Microbiology and Molecular Genetics, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Saumendra N Sarkar
- Department of Microbiology and Molecular Genetics, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Simon C Watkins
- Department of Cell Biology, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | - Roderick J O'Sullivan
- Department of Pharmacology and Chemical Biology, UPMC Hillman Cancer Center, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA.
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131
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Li F, Sun Q, Liu K, Han H, Lin N, Cheng Z, Cai Y, Tian F, Mao Z, Tong T, Zhao W. The deubiquitinase OTUD5 regulates Ku80 stability and non-homologous end joining. Cell Mol Life Sci 2019; 76:3861-3873. [PMID: 30980112 PMCID: PMC11105630 DOI: 10.1007/s00018-019-03094-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 04/01/2019] [Accepted: 04/03/2019] [Indexed: 02/03/2023]
Abstract
The ability of cells to repair DNA double-strand breaks (DSBs) is important for maintaining genome stability and eliminating oncogenic DNA lesions. Two distinct and complementary pathways, non-homologous end joining (NHEJ) and homologous recombination (HR), are employed by mammalian cells to repair DNA DSBs. Each pathway is tightly controlled in response to increased DSBs. The Ku heterodimer has been shown to play a regulatory role in NHEJ repair. Ku80 ubiquitination contributes to the selection of a DSB repair pathway by causing the removal of Ku heterodimers from DSB sites. However, whether Ku80 deubiquitination also plays a role in regulating DSB repair is unknown. To address this question, we performed a comprehensive study of the deubiquitinase specific for Ku80, and our study showed that the deubiquitinase OTUD5 serves as an important regulator of NHEJ repair by increasing the stability of Ku80. Further studies revealed that OTUD5 depletion impaired NHEJ repair, and hence reduced overall DSB repair. Furthermore, OTUD5-depleted cells displayed excess end resection; as a result, HR repair was facilitated by OTUD5 depletion during the S/G2 phase. In summary, our study demonstrates that OTUD5 is a specific deubiquitinase for Ku80 and establishes OTUD5 as an important and positive regulator of NHEJ repair.
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Affiliation(s)
- Fangzhou Li
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, 38 Xueyuan Road, Beijing, 100191, China
| | - Qianqian Sun
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, 38 Xueyuan Road, Beijing, 100191, China
| | - Kun Liu
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, 38 Xueyuan Road, Beijing, 100191, China
| | - Haichao Han
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, 38 Xueyuan Road, Beijing, 100191, China
| | - Ning Lin
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, 38 Xueyuan Road, Beijing, 100191, China
| | - Zhongyi Cheng
- Jingjie PTM BioLab, Co. Ltd, Hangzhou Economic and Technological Development Area, Hangzhou, 310018, China
| | - Yueming Cai
- Rheumatic Immunology Department, Peking University Shenzhen Hospital, Shenzhen, 518035, China
| | - Feng Tian
- Department of Laboratory Animal Science, Peking University Health Science Center, 38 Xueyuan Road, Beijing, 100191, China
| | - Zebin Mao
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, 38 Xueyuan Road, Beijing, 100191, China
| | - Tanjun Tong
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, 38 Xueyuan Road, Beijing, 100191, China
| | - Wenhui Zhao
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, 38 Xueyuan Road, Beijing, 100191, China.
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132
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Wu Q, Liang S, Ochi T, Chirgadze DY, Huiskonen JT, Blundell TL. Understanding the structure and role of DNA-PK in NHEJ: How X-ray diffraction and cryo-EM contribute in complementary ways. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 147:26-32. [DOI: 10.1016/j.pbiomolbio.2019.03.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 03/12/2019] [Accepted: 03/26/2019] [Indexed: 12/13/2022]
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133
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Single-Strand Annealing Plays a Major Role in Double-Strand DNA Break Repair following CRISPR-Cas9 Cleavage in Leishmania. mSphere 2019; 4:4/4/e00408-19. [PMID: 31434745 PMCID: PMC6706467 DOI: 10.1128/msphere.00408-19] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
CRISPR-Cas9 genome editing relies on an efficient double-strand DNA break (DSB) and repair. Contrary to mammalian cells, the protozoan parasite Leishmania lacks the most efficient nonhomologous end-joining pathway and uses microhomology-mediated end joining (MMEJ) and, occasionally, homology-directed repair to repair DSBs. Here, we reveal that Leishmania predominantly uses single-strand annealing (SSA) (>90%) instead of MMEJ (<10%) for DSB repair (DSBR) following CRISPR targeting of the miltefosine transporter gene, resulting in 9-, 18-, 20-, and 29-kb sequence deletions and multiple gene codeletions. Strikingly, when targeting the Leishmania donovani LdBPK_241510 gene, SSA even occurred by using direct repeats 77 kb apart, resulting in the codeletion of 15 Leishmania genes, though with a reduced frequency. These data strongly indicate that DSBR is not efficient in Leishmania, which explains why more than half of DSBs led to cell death and why the CRISPR gene-targeting efficiency is low compared with that in other organisms. Since direct repeat sequences are widely distributed in the Leishmania genome, we predict that many DSBs created by CRISPR are repaired by SSA. It is also revealed that DNA polymerase theta is involved in both MMEJ and SSA in Leishmania Collectively, this study establishes that DSBR mechanisms and their competence in an organism play an important role in determining the outcome and efficacy of CRISPR gene targeting. These observations emphasize the use of donor DNA templates to improve gene editing specificity and efficiency in Leishmania In addition, we developed a novel Staphylococcus aureus Cas9 constitutive expression vector (pLdSaCN) for gene targeting in Leishmania IMPORTANCE Due to differences in double-strand DNA break (DSB) repair mechanisms, CRISPR-Cas9 gene editing efficiency can vary greatly in different organisms. In contrast to mammalian cells, the protozoan parasite Leishmania uses microhomology-mediated end joining (MMEJ) and, occasionally, homology-directed repair (HDR) to repair DSBs but lacks the nonhomologous end-joining pathway. Here, we show that Leishmania predominantly uses single-strand annealing (SSA) instead of MMEJ for DSB repairs (DSBR), resulting in large deletions that can include multiple genes. This strongly indicates that the overall DSBR in Leishmania is inefficient and therefore can influence the outcome of CRISPR-Cas9 gene editing, highlighting the importance of using a donor DNA to improve gene editing fidelity and efficiency in Leishmania.
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134
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Rozov SM, Permyakova NV, Deineko EV. The Problem of the Low Rates of CRISPR/Cas9-Mediated Knock-ins in Plants: Approaches and Solutions. Int J Mol Sci 2019; 20:E3371. [PMID: 31323994 PMCID: PMC6651222 DOI: 10.3390/ijms20133371] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 06/28/2019] [Accepted: 07/05/2019] [Indexed: 11/16/2022] Open
Abstract
The main number of genome editing events in plant objects obtained during the last decade with the help of specific nucleases zinc finger (ZFN), transcription activator-like effector nucleases (TALEN), and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas are the microindels causing frameshift and subsequent gene knock-out. The knock-ins of genes or their parts, i.e., the insertion of them into a target genome region, are between one and two orders of magnitude less frequent. First and foremost, this is associated with the specific features of the repair systems of higher eukaryotes and the availability of the donor template in accessible proximity during double-strand break (DSB) repair. This review briefs the main repair pathways in plants according to the aspect of their involvement in genome editing. The main methods for increasing the frequency of knock-ins are summarized both along the homologous recombination pathway and non-homologous end joining, which can be used for plant objects.
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Affiliation(s)
- Serge M Rozov
- Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia.
| | - Natalya V Permyakova
- Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Elena V Deineko
- Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Department of Plant Physiology and Biotechnology, Tomsk State University, Tomsk 634050, Russia
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135
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Abstract
All organisms must protect their genome from constantly occurring DNA damage. To this end, cells have evolved complex pathways for repairing sites of DNA lesions, and multiple in vitro and in vivo techniques have been developed to study these processes. In this review, we discuss the commonly used laser microirradiation method for monitoring the accumulation of repair proteins at DNA damage sites in cells, and we outline several strategies for deriving kinetic models from such experimental data. We discuss an example of how in vitro measurements and in vivo microirradation experiments complement each other to provide insight into the mechanism of PARP1 recruitment to DNA lesions. We also discuss a strategy to combine data obtained for the recruitment of many different proteins in a move toward fully quantitating the spatiotemporal relationships between various damage responses, and we outline potential venues for future development in the field.
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136
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Schulz A, Meyer F, Dubrovska A, Borgmann K. Cancer Stem Cells and Radioresistance: DNA Repair and Beyond. Cancers (Basel) 2019; 11:cancers11060862. [PMID: 31234336 PMCID: PMC6627210 DOI: 10.3390/cancers11060862] [Citation(s) in RCA: 169] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 06/17/2019] [Accepted: 06/18/2019] [Indexed: 12/12/2022] Open
Abstract
The current preclinical and clinical findings demonstrate that, in addition to the conventional clinical and pathological indicators that have a prognostic value in radiation oncology, the number of cancer stem cells (CSCs) and their inherent radioresistance are important parameters for local control after radiotherapy. In this review, we discuss the molecular mechanisms of CSC radioresistance attributable to DNA repair mechanisms and the development of CSC-targeted therapies for tumor radiosensitization. We also discuss the current challenges in preclinical and translational CSC research including the high inter- and intratumoral heterogeneity, plasticity of CSCs, and microenvironment-stimulated tumor cell reprogramming.
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Affiliation(s)
- Alexander Schulz
- OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany.
| | - Felix Meyer
- Laboratory of Radiobiology & Experimental Radiooncology, Department of Radiotherapy and Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany.
| | - Anna Dubrovska
- OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany.
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, 01328 Dresden, Germany.
- German Cancer Consortium (DKTK), Partner Site Dresden, 01307 Dresden, Germany.
- German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
| | - Kerstin Borgmann
- Laboratory of Radiobiology & Experimental Radiooncology, Department of Radiotherapy and Radiooncology, Center of Oncology, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany.
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137
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Radiation-dose-dependent functional synergisms between ATM, ATR and DNA-PKcs in checkpoint control and resection in G 2-phase. Sci Rep 2019; 9:8255. [PMID: 31164689 PMCID: PMC6547644 DOI: 10.1038/s41598-019-44771-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 04/23/2019] [Indexed: 12/31/2022] Open
Abstract
Using data generated with cells exposed to ionizing-radiation (IR) in G2-phase of the cell cycle, we describe dose-dependent interactions between ATM, ATR and DNA-PKcs revealing unknown mechanistic underpinnings for two key facets of the DNA damage response: DSB end-resection and G2-checkpoint activation. At low IR-doses that induce low DSB-numbers in the genome, ATM and ATR regulate epistatically the G2-checkpoint, with ATR at the output-node, interfacing with the cell-cycle predominantly through Chk1. Strikingly, at low IR-doses, ATM and ATR epistatically regulate also resection, and inhibition of either activity fully suppresses resection. At high IR-doses that induce high DSB-numbers in the genome, the tight ATM/ATR coupling relaxes and independent outputs to G2-checkpoint and resection occur. Consequently, both kinases must be inhibited to fully suppress checkpoint activation and resection. DNA-PKcs integrates to the ATM/ATR module by regulating resection at all IR-doses, with defects in DNA-PKcs causing hyper-resection and G2-checkpoint hyper-activation. Notably, hyper-resection is absent from other c-NHEJ mutants. Thus, DNA-PKcs specifically regulates resection and adjusts the activation of the ATM/ATR module. We propose that selected DSBs are shepherd by DNA-PKcs from c-NHEJ to resection-dependent pathways for processing under the regulatory supervision of the ATM/ATR module.
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138
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Zhong Y, Pan B, Zhu J, Fu H, Zheng X. RNase L facilitates the repair of DNA double-strand breaks through the nonhomologous end-joining pathway. FEBS Lett 2019; 593:1190-1200. [PMID: 31062340 DOI: 10.1002/1873-3468.13426] [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: 12/27/2018] [Revised: 03/18/2019] [Accepted: 03/24/2019] [Indexed: 11/08/2022]
Abstract
RNA molecules have been found to play important roles in DNA double-strand break (DSB) repair, but the exact underlying mechanism remains unclear. Here, we aimed to clarify the function of RNase L, an important ribonuclease in the immune system of vertebrates, in DSB repair. Knockdown of RNase L reduces cell survival after induction of DSBs by ionizing radiation or camptothecin and causes a significant decrease in DSB repair, as evidenced by an increase in the extent of phosphorylation of histone H2AX on Ser139 (γH2AX) and γH2AX nuclear foci formation. Thus, our findings indicate that RNase L interacts with the core factors involved in DNA end joining, such as XRCC4 and Lig4, and facilitates DSB repair through the nonhomologous end-joining pathway.
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Affiliation(s)
- Yiran Zhong
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, China
| | - Bingxin Pan
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, China.,Anhui Medical University, Hefei, China
| | - Jie Zhu
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, China
| | - Hanjiang Fu
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, China
| | - Xiaofei Zheng
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, China
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139
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Miermont A, Antolović V, Lenn T, Nichols JME, Millward LJ, Chubb JR. The fate of cells undergoing spontaneous DNA damage during development. Development 2019; 146:dev174268. [PMID: 30975700 PMCID: PMC6602350 DOI: 10.1242/dev.174268] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 04/03/2019] [Indexed: 12/20/2022]
Abstract
Embryonic development involves extensive and often rapid cell proliferation. An unavoidable side effect of cell proliferation is DNA damage. The consequences of spontaneous DNA damage during development are not clear. Here, we define an approach to determine the effects of DNA damage on cell fate choice. Using single cell transcriptomics, we identified a subpopulation of Dictyostelium cells experiencing spontaneous DNA damage. Damaged cells displayed high expression of rad51, with the gene induced by multiple types of genotoxic stress. Using live imaging, we tracked high Rad51 cells from differentiation onset until cell fate assignment. High Rad51 cells were shed from multicellular structures, excluding damaged cells from the spore population. Cell shedding resulted from impaired cell motility and defective cell-cell adhesion, with damaged cells additionally defective in activation of spore gene expression. These data indicate DNA damage is not insulated from other aspects of cell physiology during development and multiple features of damaged cells prevent propagation of genetic error. Our approach is generally applicable for monitoring rare subpopulations during development, and permits analysis of developmental perturbations occurring within a physiological dynamic range.
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Affiliation(s)
- Agnes Miermont
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, London, UK
| | - Vlatka Antolović
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, London, UK
| | - Tchern Lenn
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, London, UK
| | - John M E Nichols
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, London, UK
| | - Lindsey J Millward
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, London, UK
| | - Jonathan R Chubb
- MRC Laboratory for Molecular Cell Biology and Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, London, UK
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140
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Guard SE, Poss ZC, Ebmeier CC, Pagratis M, Simpson H, Taatjes DJ, Old WM. The nuclear interactome of DYRK1A reveals a functional role in DNA damage repair. Sci Rep 2019; 9:6539. [PMID: 31024071 PMCID: PMC6483993 DOI: 10.1038/s41598-019-42990-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 04/12/2019] [Indexed: 12/21/2022] Open
Abstract
The chromosome 21 encoded protein kinase DYRK1A is essential for normal human development. Mutations in DYRK1A underlie a spectrum of human developmental disorders, and increased dosage in trisomy 21 is implicated in Down syndrome related pathologies. DYRK1A regulates a diverse array of cellular processes through physical interactions with substrates and binding partners in various subcellular compartments. Despite recent large-scale protein-protein interaction profiling efforts, DYRK1A interactions specific to different subcellular compartments remain largely unknown, impeding progress toward understanding emerging roles for this kinase. Here, we used immunoaffinity purification and quantitative mass spectrometry to identify nuclear interaction partners of endogenous DYRK1A. This interactome was enriched in DNA damage repair factors, transcriptional elongation factors and E3 ubiquitin ligases. We validated an interaction with RNF169, a factor that promotes homology directed repair upon DNA damage, and found that DYRK1A expression and kinase activity are required for maintenance of 53BP1 expression and subsequent recruitment to DNA damage loci. Further, DYRK1A knock out conferred resistance to ionizing radiation in colony formation assays, suggesting that DYRK1A expression decreases cell survival efficiency in response to DNA damage and points to a tumor suppressive role for this kinase.
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Affiliation(s)
- Steven E Guard
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Zachary C Poss
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Christopher C Ebmeier
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Maria Pagratis
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Helen Simpson
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Dylan J Taatjes
- Department of Biochemistry, University of Colorado, Boulder, CO, USA
| | - William M Old
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO, USA.
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, CO, USA.
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141
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Ma H, Tu LC, Chung YC, Naseri A, Grunwald D, Zhang S, Pederson T. Cell cycle- and genomic distance-dependent dynamics of a discrete chromosomal region. J Cell Biol 2019; 218:1467-1477. [PMID: 30846483 PMCID: PMC6504907 DOI: 10.1083/jcb.201807162] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 11/08/2018] [Accepted: 02/08/2019] [Indexed: 02/08/2023] Open
Abstract
In contrast to the well-studied condensation and folding of chromosomes during mitosis, their dynamics during interphase are less understood. We deployed a CRISPR-based DNA imaging system to track the dynamics of genomic loci situated kilobases to megabases apart on a single chromosome. Two distinct modes of dynamics were resolved: local movements as well as ones that might reflect translational movements of the entire domain within the nucleoplasmic space. The magnitude of both of these modes of movements increased from early to late G1, whereas the translational movements were reduced in early S phase. The local fluctuations decreased slightly in early S and more markedly in mid-late S. These newly observed movements and their cell cycle dependence suggest the existence of a hitherto unrecognized compaction-relaxation dynamic of the interphase chromosome fiber, operating concurrently with changes in the extent of overall movements of loci in the 4D genome.
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Affiliation(s)
- Hanhui Ma
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA
| | - Li-Chun Tu
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA
| | - Yu-Chieh Chung
- Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Japan
| | - Ardalan Naseri
- Department of Computer Science, University of Central Florida, Orlando, FL
| | - David Grunwald
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA
| | - Shaojie Zhang
- Department of Computer Science, University of Central Florida, Orlando, FL
| | - Thoru Pederson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA
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142
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Nakamura K, Saredi G, Becker JR, Foster BM, Nguyen NV, Beyer TE, Cesa LC, Faull PA, Lukauskas S, Frimurer T, Chapman JR, Bartke T, Groth A. H4K20me0 recognition by BRCA1-BARD1 directs homologous recombination to sister chromatids. Nat Cell Biol 2019; 21:311-318. [PMID: 30804502 PMCID: PMC6420097 DOI: 10.1038/s41556-019-0282-9] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 01/14/2019] [Indexed: 12/12/2022]
Abstract
Genotoxic DNA double-strand breaks (DSBs) can be repaired by error-free homologous recombination (HR) or mutagenic non-homologous end-joining1. HR supresses tumorigenesis1, but is restricted to the S and G2 phases of the cell cycle when a sister chromatid is present2. Breast cancer type 1 susceptibility protein (BRCA1) promotes HR by antagonizing the anti-resection factor TP53-binding protein 1(53BP1) (refs. 2-5), but it remains unknown how BRCA1 function is limited to the S and G2 phases. We show that BRCA1 recruitment requires recognition of histone H4 unmethylated at lysine 20 (H4K20me0), linking DSB repair pathway choice directly to sister chromatid availability. We identify the ankyrin repeat domain of BRCA1-associated RING domain protein 1 (BARD1)-the obligate BRCA1 binding partner3-as a reader of H4K20me0 present on new histones in post-replicative chromatin6. BARD1 ankyrin repeat domain mutations disabling H4K20me0 recognition abrogate accumulation of BRCA1 at DSBs, causing aberrant build-up of 53BP1, and allowing anti-resection activity to prevail in S and G2. Consequently, BARD1 recognition of H4K20me0 is required for HR and resistance to poly (ADP-ribose) polymerase inhibitors. Collectively, this reveals that BRCA1-BARD1 monitors the replicative state of the genome to oppose 53BP1 function, routing only DSBs within sister chromatids to HR.
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Affiliation(s)
- Kyosuke Nakamura
- Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Giulia Saredi
- Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, Sir James Black Centre, University of Dundee, Dundee, UK
| | | | - Benjamin M Foster
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Nhuong V Nguyen
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Tracey E Beyer
- Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Laura C Cesa
- Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter A Faull
- MRC London Institute of Medical Sciences, London, UK
- Francis Crick Institute, London, UK
| | - Saulius Lukauskas
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
- MRC London Institute of Medical Sciences, London, UK
- Department of Chemical Engineering, Imperial College London, London, UK
| | - Thomas Frimurer
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Till Bartke
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany.
- MRC London Institute of Medical Sciences, London, UK.
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK.
| | - Anja Groth
- Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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143
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Liu J, Nannas NJ, Fu FF, Shi J, Aspinwall B, Parrott WA, Dawe RK. Genome-Scale Sequence Disruption Following Biolistic Transformation in Rice and Maize. THE PLANT CELL 2019; 31:368-383. [PMID: 30651345 PMCID: PMC6447018 DOI: 10.1105/tpc.18.00613] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 12/13/2018] [Accepted: 01/09/2019] [Indexed: 05/20/2023]
Abstract
Biolistic transformation delivers nucleic acids into plant cells by bombarding the cells with microprojectiles, which are micron-scale, typically gold particles. Despite the wide use of this technique, little is known about its effect on the cell's genome. We biolistically transformed linear 48-kb phage lambda and two different circular plasmids into rice (Oryza sativa) and maize (Zea mays) and analyzed the results by whole genome sequencing and optical mapping. Although some transgenic events showed simple insertions, others showed extreme genome damage in the form of chromosome truncations, large deletions, partial trisomy, and evidence of chromothripsis and breakage-fusion bridge cycling. Several transgenic events contained megabase-scale arrays of introduced DNA mixed with genomic fragments assembled by nonhomologous or microhomology-mediated joining. Damaged regions of the genome, assayed by the presence of small fragments displaced elsewhere, were often repaired without a trace, presumably by homology-dependent repair (HDR). The results suggest a model whereby successful biolistic transformation relies on a combination of end joining to insert foreign DNA and HDR to repair collateral damage caused by the microprojectiles. The differing levels of genome damage observed among transgenic events may reflect the stage of the cell cycle and the availability of templates for HDR.
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Affiliation(s)
- Jianing Liu
- Department of Genetics, University of Georgia, Athens, Georgia 30602
| | - Natalie J Nannas
- Department of Biology, Hamilton College, Clinton, New York 13323
| | - Fang-Fang Fu
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602
| | - Jinghua Shi
- Bionano Genomics, San Diego, California 92121
| | - Brooke Aspinwall
- Department of Genetics, University of Georgia, Athens, Georgia 30602
| | - Wayne A Parrott
- Department of Crop and Soil Sciences, University of Georgia, Athens, Georgia 30602
| | - R Kelly Dawe
- Department of Genetics, University of Georgia, Athens, Georgia 30602
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602
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144
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DNA Ligase IV Prevents Replication Fork Stalling and Promotes Cellular Proliferation in Triple Negative Breast Cancer. J Nucleic Acids 2019; 2019:9170341. [PMID: 30838131 PMCID: PMC6374816 DOI: 10.1155/2019/9170341] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 11/27/2018] [Accepted: 01/05/2019] [Indexed: 02/07/2023] Open
Abstract
DNA damage is a hallmark of cancer, and mutation and misregulation of proteins that maintain genomic fidelity are associated with the development of multiple cancers. DNA double strand breaks are arguably considered the most deleterious type of DNA damage. The nonhomologous end-joining (NHEJ) pathway is one mechanism to repair DNA double strand breaks, and proteins involved in NHEJ may also regulate DNA replication. We previously established that DNA-PKcs, a NHEJ protein, promotes genomic stability and cell viability following cellular exposure to replication stress; we wanted to discern whether another NHEJ protein, DNA ligase IV (Lig4), shares this phenotype. Our investigations focused on triple negative breast cancer cells, as, compared to nonbasal breast cancer, LIG4 is frequently amplified, and an increased gene dose is associated with higher Lig4 expression. We depleted Lig4 using siRNA and confirmed our knockdown by qPCR and western blotting. Cell survival diminished with Lig4 depletion alone, and this was associated with increased replication fork stalling. Checkpoint protein Chk1 activation and dephosphorylation were unchanged in Lig4-depleted cells. Lig4 depletion resulted in sustained DNA-PKcs phosphorylation following hydroxyurea exposure. Understanding the effect of Lig4 on genomic replication and the replication stress response will clarify the biological ramifications of inhibiting Lig4 activity. In addition, Lig4 is an attractive clinical target for directing CRISPR/Cas9-mediated repair towards homology-directed repair and away from NHEJ, thus understanding of how diminishing Lig4 impacts cell biology is critical.
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145
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Impaired non-homologous end joining in human primary alveolar type II cells in emphysema. Sci Rep 2019; 9:920. [PMID: 30696938 PMCID: PMC6351635 DOI: 10.1038/s41598-018-37000-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 11/27/2018] [Indexed: 12/13/2022] Open
Abstract
Emphysema is characterized by alveolar wall destruction induced mainly by cigarette smoke. Oxidative damage of DNA may contribute to the pathophysiology of this disease. We studied the impairment of the non-homologous end joining (NHEJ) repair pathway and DNA damage in alveolar type II (ATII) cells and emphysema development. We isolated primary ATII cells from control smokers, nonsmokers, and patients with emphysema to determine DNA damage and repair. We found higher reactive oxygen species generation and DNA damage in ATII cells obtained from individuals with this disease in comparison with controls. We also observed low phosphorylation of H2AX, which activates DSBs repair signaling, in emphysema. Our results indicate the impairement of NHEJ, as detected by low XLF expression. We also analyzed the role of DJ-1, which has a cytoprotective activity. We detected DJ-1 and XLF interaction in ATII cells in emphysema, which suggests the impairment of their function. Moreover, we found that DJ-1 KO mice are more susceptible to DNA damage induced by cigarette smoke. Our results suggest that oxidative DNA damage and ineffective the DSBs repair via the impaired NHEJ may contribute to ATII cell death in emphysema.
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146
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Abstract
DNA double strand breaks (DSBs) are a serious threat to genome stability and cell viability. Accurate detection of DSBs is critical for the basic understanding of cellular response to ionizing radiation. Recruitment and retention of DNA repair and response proteins at DSBs can be conveniently visualized by fluorescence imaging (often called ionizing radiation-induced foci) both in live and fixed cells. In this chapter, we describe a live cell imaging methodology that directly monitors induction and repair of single DSB, recruitment kinetics of DSB repair/sensor factors to DSB sites, and dynamic interaction of DSB repair/sensor proteins with DSBs at single-cell level. Additionally, the methodology described in this chapter can be readily adapted to other DSBs repair/sensor factors and cell types.
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Affiliation(s)
- Eiichiro Mori
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Aroumougame Asaithamby
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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147
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Cimini S, Gualtieri C, Macovei A, Balestrazzi A, De Gara L, Locato V. Redox Balance-DDR-miRNA Triangle: Relevance in Genome Stability and Stress Responses in Plants. FRONTIERS IN PLANT SCIENCE 2019; 10:989. [PMID: 31428113 PMCID: PMC6688120 DOI: 10.3389/fpls.2019.00989] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/15/2019] [Indexed: 05/05/2023]
Abstract
Plants are continuously faced with complex environmental conditions which can affect the oxidative metabolism and photosynthetic efficiency, thus leading to the over-production of reactive oxygen species (ROS). Over a certain threshold, ROS can damage DNA. DNA damage, unless repaired, can affect genome stability, thus interfering with cell survival and severely reducing crop productivity. A complex network of pathways involved in DNA damage response (DDR) needs to be activated in order to maintain genome integrity. The expression of specific genes belonging to these pathways can be used as indicators of oxidative DNA damage and effective DNA repair in plants subjected to stress conditions. Managing ROS levels by modulating their production and scavenging systems shifts the role of these compounds from toxic molecules to key messengers involved in plant tolerance acquisition. Oxidative and anti-oxidative signals normally move among the different cell compartments, including the nucleus, cytosol, and organelles. Nuclei are dynamically equipped with different redox systems, such as glutathione (GSH), thiol reductases, and redox regulated transcription factors (TFs). The nuclear redox network participates in the regulation of the DNA metabolism, in terms of transcriptional events, replication, and repair mechanisms. This mainly occurs through redox-dependent regulatory mechanisms comprising redox buffering and post-translational modifications, such as the thiol-disulphide switch, glutathionylation, and S-nitrosylation. The regulatory role of microRNAs (miRNAs) is also emerging for the maintenance of genome stability and the modulation of antioxidative machinery under adverse environmental conditions. In fact, redox systems and DDR pathways can be controlled at a post-transcriptional level by miRNAs. This review reports on the interconnections between the DDR pathways and redox balancing systems. It presents a new dynamic picture by taking into account the shared regulatory mechanism mediated by miRNAs in plant defense responses to stress.
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Affiliation(s)
- Sara Cimini
- Unit of Food Science and Human Nutrition, Campus Bio-Medico University of Rome, Rome, Italy
| | - Carla Gualtieri
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - Anca Macovei
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - Alma Balestrazzi
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - Laura De Gara
- Unit of Food Science and Human Nutrition, Campus Bio-Medico University of Rome, Rome, Italy
| | - Vittoria Locato
- Unit of Food Science and Human Nutrition, Campus Bio-Medico University of Rome, Rome, Italy
- *Correspondence: Vittoria Locato,
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148
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Que Q, Chen Z, Kelliher T, Skibbe D, Dong S, Chilton MD. Plant DNA Repair Pathways and Their Applications in Genome Engineering. Methods Mol Biol 2019; 1917:3-24. [PMID: 30610624 DOI: 10.1007/978-1-4939-8991-1_1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Remarkable progress in the development of technologies for sequence-specific modification of primary DNA sequences has enabled the precise engineering of crops with novel characteristics. These programmable sequence-specific modifiers include site-directed nucleases (SDNs) and base editors (BEs). Currently, these genome editing machineries can be targeted to specific chromosomal locations to induce sequence changes. However, the sequence mutation outcomes are often greatly influenced by the type of DNA damage being generated, the status of host DNA repair machinery, and the presence and structure of DNA repair donor molecule. The outcome of sequence modification from repair of DNA double-strand breaks (DSBs) is often uncontrollable, resulting in unpredictable sequence insertions or deletions of various sizes. For base editing, the precision of intended edits is much higher, but the efficiency can vary greatly depending on the type of BE used or the activity of the endogenous DNA repair systems. This article will briefly review the possible DNA repair pathways present in the plant cells commonly used for generating edited variants for genome engineering applications. We will discuss the potential use of DNA repair mechanisms for developing and improving methodologies to enhance genome engineering efficiency and to direct DNA repair processes toward the desired outcomes.
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Affiliation(s)
- Qiudeng Que
- Seeds Research, Syngenta Crop Protection, LLC, Research Triangle Park, NC, USA.
| | - Zhongying Chen
- Seeds Research, Syngenta Crop Protection, LLC, Research Triangle Park, NC, USA
| | - Tim Kelliher
- Seeds Research, Syngenta Crop Protection, LLC, Research Triangle Park, NC, USA
| | - David Skibbe
- Seeds Research, Syngenta Crop Protection, LLC, Research Triangle Park, NC, USA
| | - Shujie Dong
- Seeds Research, Syngenta Crop Protection, LLC, Research Triangle Park, NC, USA
| | - Mary-Dell Chilton
- Seeds Research, Syngenta Crop Protection, LLC, Research Triangle Park, NC, USA
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149
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Smirnikhina SA, Anuchina AA, Lavrov AV. Ways of improving precise knock-in by genome-editing technologies. Hum Genet 2018; 138:1-19. [DOI: 10.1007/s00439-018-1953-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 10/29/2018] [Indexed: 02/07/2023]
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150
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Sizemore ST, Zhang M, Cho JH, Sizemore GM, Hurwitz B, Kaur B, Lehman NL, Ostrowski MC, Robe PA, Miao W, Wang Y, Chakravarti A, Xia F. Pyruvate kinase M2 regulates homologous recombination-mediated DNA double-strand break repair. Cell Res 2018; 28:1090-1102. [PMID: 30297868 PMCID: PMC6218445 DOI: 10.1038/s41422-018-0086-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 07/23/2018] [Accepted: 08/16/2018] [Indexed: 02/08/2023] Open
Abstract
Resistance to genotoxic therapies is a primary cause of treatment failure and tumor recurrence. The underlying mechanisms that activate the DNA damage response (DDR) and allow cancer cells to escape the lethal effects of genotoxic therapies remain unclear. Here, we uncover an unexpected mechanism through which pyruvate kinase M2 (PKM2), the highly expressed PK isoform in cancer cells and a master regulator of cancer metabolic reprogramming, integrates with the DDR to directly promote DNA double-strand break (DSB) repair. In response to ionizing radiation and oxidative stress, ATM phosphorylates PKM2 at T328 resulting in its nuclear accumulation. pT328-PKM2 is required and sufficient to promote homologous recombination (HR)-mediated DNA DSB repair through phosphorylation of CtBP-interacting protein (CtIP) on T126 to increase CtIP's recruitment at DSBs and resection of DNA ends. Disruption of the ATM-PKM2-CtIP axis sensitizes cancer cells to a variety of DNA-damaging agents and PARP1 inhibition. Furthermore, increased nuclear pT328-PKM2 level is associated with significantly worse survival in glioblastoma patients. Combined, these data advocate the use of PKM2-targeting strategies as a means to not only disrupt cancer metabolism but also inhibit an important mechanism of resistance to genotoxic therapies.
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Affiliation(s)
- Steven T Sizemore
- Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
| | - Manchao Zhang
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, USA
| | - Ju Hwan Cho
- Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
| | - Gina M Sizemore
- Department of Cancer Biology & Genetics, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
| | - Brian Hurwitz
- Department of Neurological Surgery, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
| | - Balveen Kaur
- Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
- Department of Neurological Surgery, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
| | - Norman L Lehman
- Department of Pathology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
| | - Michael C Ostrowski
- Department of Cancer Biology & Genetics, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
| | - Pierre A Robe
- Department of Neurology and Neurosurgery, Rudolf Magnus Brain Institute, University Medical Center of Utrecht, Utrecht, The Netherlands
- Departments of Neurosurgery and Human Genetics, University of Liege, Liege, Belgium
| | - Weili Miao
- Department of Chemistry, University of California, Riverside, CA, 92521, USA
| | - Yinsheng Wang
- Department of Chemistry, University of California, Riverside, CA, 92521, USA
| | - Arnab Chakravarti
- Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, OH, 43210, USA
| | - Fen Xia
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, USA.
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