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Wang K, Huang H, Zhan Q, Ding H, Li Y. Toll-like receptors in health and disease. MedComm (Beijing) 2024; 5:e549. [PMID: 38685971 PMCID: PMC11057423 DOI: 10.1002/mco2.549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 03/17/2024] [Accepted: 03/26/2024] [Indexed: 05/02/2024] Open
Abstract
Toll-like receptors (TLRs) are inflammatory triggers and belong to a family of pattern recognition receptors (PRRs) that are central to the regulation of host protective adaptive immune responses. Activation of TLRs in innate immune myeloid cells directs lymphocytes to produce the most appropriate effector responses to eliminate infection and maintain homeostasis of the body's internal environment. Inappropriate TLR stimulation can lead to the development of general autoimmune diseases as well as chronic and acute inflammation, and even cancer. Therefore, TLRs are expected to be targets for therapeutic treatment of inflammation-related diseases, autoimmune diseases, microbial infections, and human cancers. This review summarizes the recent discoveries in the molecular and structural biology of TLRs. The role of different TLR signaling pathways in inflammatory diseases, autoimmune diseases such as diabetes, cardiovascular diseases, respiratory diseases, digestive diseases, and even cancers (oral, gastric, breast, colorectal) is highlighted and summarizes new drugs and related clinical treatments in clinical trials, providing an overview of the potential and prospects of TLRs for the treatment of TLR-related diseases.
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Affiliation(s)
- Kunyu Wang
- Department of Head and Neck Oncology Surgery, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengduChina
| | - Hanyao Huang
- Department of Oral and Maxillofacial Surgery, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengduSichuanChina
| | - Qi Zhan
- Department of Head and Neck Oncology Surgery, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengduChina
| | - Haoran Ding
- Department of Head and Neck Oncology Surgery, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengduChina
| | - Yi Li
- Department of Head and Neck Oncology Surgery, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengduChina
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2
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Gohil D, Sarker AH, Roy R. Base Excision Repair: Mechanisms and Impact in Biology, Disease, and Medicine. Int J Mol Sci 2023; 24:14186. [PMID: 37762489 PMCID: PMC10531636 DOI: 10.3390/ijms241814186] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/12/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Base excision repair (BER) corrects forms of oxidative, deamination, alkylation, and abasic single-base damage that appear to have minimal effects on the helix. Since its discovery in 1974, the field has grown in several facets: mechanisms, biology and physiology, understanding deficiencies and human disease, and using BER genes as potential inhibitory targets to develop therapeutics. Within its segregation of short nucleotide (SN-) and long patch (LP-), there are currently six known global mechanisms, with emerging work in transcription- and replication-associated BER. Knockouts (KOs) of BER genes in mouse models showed that single glycosylase knockout had minimal phenotypic impact, but the effects were clearly seen in double knockouts. However, KOs of downstream enzymes showed critical impact on the health and survival of mice. BER gene deficiency contributes to cancer, inflammation, aging, and neurodegenerative disorders. Medicinal targets are being developed for single or combinatorial therapies, but only PARP and APE1 have yet to reach the clinical stage.
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Affiliation(s)
- Dhara Gohil
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA;
| | - Altaf H. Sarker
- Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA;
| | - Rabindra Roy
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA;
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Liu W, Yasui M, Sassa A, You X, Wan J, Cao Y, Xi J, Zhang X, Honma M, Luan Y. FTO regulates the DNA damage response via effects on cell-cycle progression. MUTATION RESEARCH/GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2023; 887:503608. [PMID: 37003652 DOI: 10.1016/j.mrgentox.2023.503608] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 03/02/2023]
Abstract
The fat mass and obesity-associated protein FTO is an "eraser" of N6-methyladenosine, the most abundant mRNA modification. FTO plays important roles in tumorigenesis. However, its activities have not been fully elucidated and its possible involvement in DNA damage - the early driving event in tumorigenesis - remains poorly characterized. Here, we have investigated the role of FTO in the DNA damage response (DDR) and its underlying mechanisms. We demonstrate that FTO responds to various DNA damage stimuli. FTO is overexpressed in mice following exposure to the promutagens aristolochic acid I and benzo[a]pyrene. Knockout of the FTO gene in TK6 cells, via CRISPR/Cas9, increased genotoxicity induced by DNA damage stimuli (micronucleus and TK mutation assays). Cisplatin- and diepoxybutane-induced micronucleus frequencies and methyl methanesulfonate- and azathioprine-induced TK mutant frequencies were also higher in FTO KO cells. We investigated the potential roles of FTO in DDR. RNA sequencing and enrichment analysis revealed that FTO deletion disrupted the p38 MAPK pathway and inhibited the activation of nucleotide excision repair and cell-cycle-related pathways following cisplatin (DNA intrastrand cross-links) treatment. These effects were confirmed by western blotting and qRT-PCR. FTO deletion impaired cell-cycle arrest at the G2/M phase following cisplatin and diepoxybutane treatment (flow cytometry analysis). Our findings demonstrated that FTO is involved in several aspects of DDR, acting, at least in part, by impairing cell cycle progression.
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Arvanitaki ES, Stratigi K, Garinis GA. DNA damage, inflammation and aging: Insights from mice. FRONTIERS IN AGING 2022; 3:973781. [PMID: 36160606 PMCID: PMC9490123 DOI: 10.3389/fragi.2022.973781] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/26/2022] [Indexed: 11/24/2022]
Abstract
Persistent DNA lesions build up with aging triggering inflammation, the body’s first line of immune defense strategy against foreign pathogens and irritants. Once established, DNA damage-driven inflammation takes on a momentum of its own, due to the amplification and feedback loops of the immune system leading to cellular malfunction, tissue degenerative changes and metabolic complications. Here, we discuss the use of murine models with inborn defects in genome maintenance and the DNA damage response for understanding how irreparable DNA lesions are functionally linked to innate immune signaling highlighting their relevance for developing novel therapeutic strategies against the premature onset of aging-associated diseases.
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Affiliation(s)
- Ermioni S. Arvanitaki
- Department of Biology, University of Crete, Heraklion, Greece
- Foundation for Research and Technology-Hellas, Institute of Molecular Biology and Biotechnology, Heraklion, Greece
| | | | - George A. Garinis
- Department of Biology, University of Crete, Heraklion, Greece
- Foundation for Research and Technology-Hellas, Institute of Molecular Biology and Biotechnology, Heraklion, Greece
- *Correspondence: George A. Garinis,
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5
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Hindi NN, Elsakrmy N, Ramotar D. The base excision repair process: comparison between higher and lower eukaryotes. Cell Mol Life Sci 2021; 78:7943-7965. [PMID: 34734296 PMCID: PMC11071731 DOI: 10.1007/s00018-021-03990-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 09/08/2021] [Accepted: 10/14/2021] [Indexed: 01/01/2023]
Abstract
The base excision repair (BER) pathway is essential for maintaining the stability of DNA in all organisms and defects in this process are associated with life-threatening diseases. It is involved in removing specific types of DNA lesions that are induced by both exogenous and endogenous genotoxic substances. BER is a multi-step mechanism that is often initiated by the removal of a damaged base leading to a genotoxic intermediate that is further processed before the reinsertion of the correct nucleotide and the restoration of the genome to a stable structure. Studies in human and yeast cells, as well as fruit fly and nematode worms, have played important roles in identifying the components of this conserved DNA repair pathway that maintains the integrity of the eukaryotic genome. This review will focus on the components of base excision repair, namely, the DNA glycosylases, the apurinic/apyrimidinic endonucleases, the DNA polymerase, and the ligases, as well as other protein cofactors. Functional insights into these conserved proteins will be provided from humans, Saccharomyces cerevisiae, Drosophila melanogaster, and Caenorhabditis elegans, and the implications of genetic polymorphisms and knockouts of the corresponding genes.
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Affiliation(s)
- Nagham Nafiz Hindi
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar
| | - Noha Elsakrmy
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar
| | - Dindial Ramotar
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar.
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SenGupta T, Palikaras K, Esbensen YQ, Konstantinidis G, Galindo FJN, Achanta K, Kassahun H, Stavgiannoudaki I, Bohr VA, Akbari M, Gaare J, Tzoulis C, Tavernarakis N, Nilsen H. Base excision repair causes age-dependent accumulation of single-stranded DNA breaks that contribute to Parkinson disease pathology. Cell Rep 2021; 36:109668. [PMID: 34496255 PMCID: PMC8441048 DOI: 10.1016/j.celrep.2021.109668] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 05/26/2021] [Accepted: 08/13/2021] [Indexed: 01/24/2023] Open
Abstract
Aging, genomic stress, and mitochondrial dysfunction are risk factors for neurodegenerative pathologies, such as Parkinson disease (PD). Although genomic instability is associated with aging and mitochondrial impairment, the underlying mechanisms are poorly understood. Here, we show that base excision repair generates genomic stress, promoting age-related neurodegeneration in a Caenorhabditis elegans PD model. A physiological level of NTH-1 DNA glycosylase mediates mitochondrial and nuclear genomic instability, which promote degeneration of dopaminergic neurons in older nematodes. Conversely, NTH-1 deficiency protects against α-synuclein-induced neurotoxicity, maintaining neuronal function with age. This apparent paradox is caused by modulation of mitochondrial transcription in NTH-1-deficient cells, and this modulation activates LMD-3, JNK-1, and SKN-1 and induces mitohormesis. The dependance of neuroprotection on mitochondrial transcription highlights the integration of BER and transcription regulation during physiological aging. Finally, whole-exome sequencing of genomic DNA from patients with idiopathic PD suggests that base excision repair might modulate susceptibility to PD in humans. Incomplete base excision repair is a source of genomic stress during aging The NTH-1 DNA glycosylase is a key mediator of age-dependent genomic instability Compromised NTH-1 activity promotes neuroprotection in PD nematodes NTH-1 deficiency triggers LMD-3/JNK-1/SKN-1-dependent mitohormetic response
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Affiliation(s)
- Tanima SenGupta
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway; Department of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway
| | - Konstantinos Palikaras
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Hellas, Greece; Department of Physiology, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Ying Q Esbensen
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway; Department of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway
| | - Georgios Konstantinidis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Hellas, Greece
| | - Francisco Jose Naranjo Galindo
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway; Department of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway
| | - Kavya Achanta
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, SUND, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Henok Kassahun
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway
| | - Ioanna Stavgiannoudaki
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Hellas, Greece
| | - Vilhelm A Bohr
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, SUND, University of Copenhagen, 2200 Copenhagen, Denmark; DNA Repair Section, National Institute on Aging, 251 Bayview Boulevard, Baltimore, MD, USA
| | - Mansour Akbari
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, SUND, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Johannes Gaare
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, 5021 Bergen, Norway; Department of Clinical Medicine, University of Bergen, Pb 7804, 5020 Bergen, Norway
| | - Charalampos Tzoulis
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, 5021 Bergen, Norway; Department of Clinical Medicine, University of Bergen, Pb 7804, 5020 Bergen, Norway
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Hellas, Greece; Department of Basic Sciences, Faculty of Medicine, University of Crete, Heraklion, 70013 Crete, Greece.
| | - Hilde Nilsen
- Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway; Department of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway.
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Kay JE, Mirabal S, Briley WE, Kimoto T, Poutahidis T, Ragan T, So PT, Wadduwage DN, Erdman SE, Engelward BP. Analysis of mutations in tumor and normal adjacent tissue via fluorescence detection. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2021; 62:108-123. [PMID: 33314311 PMCID: PMC7880898 DOI: 10.1002/em.22419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 12/04/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
Inflammation is a major risk factor for many types of cancer, including colorectal. There are two fundamentally different mechanisms by which inflammation can contribute to carcinogenesis. First, reactive oxygen and nitrogen species (RONS) can damage DNA to cause mutations that initiate cancer. Second, inflammatory cytokines and chemokines promote proliferation, migration, and invasion. Although it is known that inflammation-associated RONS can be mutagenic, the extent to which they induce mutations in intestinal stem cells has been little explored. Furthermore, it is now widely accepted that cancer is caused by successive rounds of clonal expansion with associated de novo mutations that further promote tumor development. As such, we aimed to understand the extent to which inflammation promotes clonal expansion in normal and tumor tissue. Using an engineered mouse model that is prone to cancer and within which mutant cells fluoresce, here we have explored the impact of inflammation on de novo mutagenesis and clonal expansion in normal and tumor tissue. While inflammation is strongly associated with susceptibility to cancer and a concomitant increase in the overall proportion of mutant cells in the tissue, we did not observe an increase in mutations in normal adjacent tissue. These results are consistent with opportunities for de novo mutations and clonal expansion during tumor growth, and they suggest protective mechanisms that suppress the risk of inflammation-induced accumulation of mutant cells in normal tissue.
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Affiliation(s)
- Jennifer E. Kay
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA
| | - Sheyla Mirabal
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA
| | | | - Takafumi Kimoto
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA
| | - Theofilos Poutahidis
- Laboratory of Pathology, Faculty of Veterinary Medicine, School of Health Sciences, Aristotle University of Thessaloniki, Greece
| | | | - Peter T. So
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA
| | - Dushan N. Wadduwage
- The John Harvard Distinguished Science Fellows Program, Harvard University, Cambridge, MA
- Center for Advanced Imaging, Harvard University, Cambridge, MA, USA
| | - Susan E. Erdman
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA
| | - Bevin P. Engelward
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA
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Al-Shaheri FN, Al-Shami KM, Gamal EH, Mahasneh AA, Ayoub NM. Association of DNA repair gene polymorphisms with colorectal cancer risk and treatment outcomes. Exp Mol Pathol 2019; 113:104364. [PMID: 31881200 DOI: 10.1016/j.yexmp.2019.104364] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/16/2019] [Accepted: 12/24/2019] [Indexed: 02/07/2023]
Abstract
Colorectal cancer (CRC) is the third most common carcinoma worldwide. Despite the progress in screening and treatment, CRC remains a leading cause of cancer-related mortality. Alterations to normal nucleic acid processing may drive neoplastic transformation of colorectal epithelium. DNA repair machinery performs an essential function in the protection of genome by reducing the number of genetic polymorphisms/variations that may drive carcinogenicity. Four essential DNA repair systems are known which include nucleotide excision repair (NER), base excision repair (BER), mismatch repair (MMR), and double-strand break repair (DSBR). Polymorphisms of DNA repair genes have been shown to influence the risk of cancer development as well as outcomes of treatment. Several studies demonstrated the association between genetic polymorphism of DNA repair genes and increased risk of CRC in different populations. In this review, we have summarized the impact of DNA repair gene polymorphisms on risk of CRC development and treatment outcomes. Advancements of the current understanding for the impact of DNA repair gene polymorphisms on the risk and treatment of CRC may support diagnostic and predictive roles in patients with CRC.
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Affiliation(s)
- Fawaz N Al-Shaheri
- Division of Functional Genome Analysis, German Cancer Research Center (DKFZ), ImNeuenheimer Feld 580, 69120 Heidelberg, Germany; Medical Faculty Heidelberg, University of Heidelberg, ImNeuenheimer Feld 672, 69120 Heidelberg, Germany; Faculty of Applied Medical Sciences, Department of Medical Laboratory Sciences, Jordan University of Science and Technology, Irbid, Jordan.
| | - Kamal M Al-Shami
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, 720 South Donahue Drive, Auburn, Alabama 36849, United States of America; Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid 22110, Jordan.
| | - Eshrak H Gamal
- Department of Oncology, Collage of Medicine, Bonn University, Germany; Faculty of Applied Medical Sciences, Department of Medical Laboratory Sciences, Jordan University of Science and Technology, Irbid, Jordan.
| | - Amjad A Mahasneh
- Department of Applied Biological Sciences, Faculty of Science and Arts, Jordan University of Science and Technology, Irbid 22110, Jordan.
| | - Nehad M Ayoub
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid 22110, Jordan.
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Kay J, Thadhani E, Samson L, Engelward B. Inflammation-induced DNA damage, mutations and cancer. DNA Repair (Amst) 2019; 83:102673. [PMID: 31387777 DOI: 10.1016/j.dnarep.2019.102673] [Citation(s) in RCA: 188] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 06/15/2019] [Accepted: 07/18/2019] [Indexed: 12/22/2022]
Abstract
The relationships between inflammation and cancer are varied and complex. An important connection linking inflammation to cancer development is DNA damage. During inflammation reactive oxygen and nitrogen species (RONS) are created to combat pathogens and to stimulate tissue repair and regeneration, but these chemicals can also damage DNA, which in turn can promote mutations that initiate and promote cancer. DNA repair pathways are essential for preventing DNA damage from causing mutations and cytotoxicity, but RONS can interfere with repair mechanisms, reducing their efficacy. Further, cellular responses to DNA damage, such as damage signaling and cytotoxicity, can promote inflammation, creating a positive feedback loop. Despite coordination of DNA repair and oxidative stress responses, there are nevertheless examples whereby inflammation has been shown to promote mutagenesis, tissue damage, and ultimately carcinogenesis. Here, we discuss the DNA damage-mediated associations between inflammation, mutagenesis and cancer.
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Affiliation(s)
- Jennifer Kay
- Department of Biological Engineering, United States.
| | | | - Leona Samson
- Department of Biological Engineering, United States; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, 02139, United States
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Kashyap D, Tuli HS, Sak K, Garg VK, Goel N, Punia S, Chaudhary A. Role of Reactive Oxygen Species in Cancer Progression. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s40495-019-00171-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Deep multi-region whole-genome sequencing reveals heterogeneity and gene-by-environment interactions in treatment-naive, metastatic lung cancer. Oncogene 2018; 38:1661-1675. [PMID: 30348992 PMCID: PMC6462862 DOI: 10.1038/s41388-018-0536-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 09/13/2018] [Accepted: 09/19/2018] [Indexed: 12/23/2022]
Abstract
Our understanding of genomic heterogeneity in lung cancer is largely based on the analysis of early-stage surgical specimens. Here we used endoscopic sampling of paired primary and intrathoracic metastatic tumors from 11 lung cancer patients to map genomic heterogeneity inoperable lung cancer with deep whole-genome sequencing. Intra-patient heterogeneity in driver or targetable mutations was predominantly in the form of copy number gain. Private mutation signatures, including patterns consistent with defects in homologous recombination, were highly variable both within and between patients. Irrespective of histotype, we observed a smaller than expected number of private mutations, suggesting that ancestral clones accumulated large mutation burdens immediately prior to metastasis. Single-region whole-genome sequencing of from 20 patients showed that tumors in ever-smokers with the strongest tobacco signatures were associated with germline variants in genes implicated in the repair of cigarette-induced DNA damage. Our results suggest that lung cancer precursors in ever-smokers accumulate large numbers of mutations prior to the formation of frank malignancy followed by rapid metastatic spread. In advanced lung cancer, germline variants in DNA repair genes may interact with the airway environment to influence the pattern of founder mutations, whereas similar interactions with the tumor microenvironment may play a role in the acquisition of mutations following metastasis.
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