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Bessho T. Up-Regulation of Non-Homologous End-Joining by MUC1. Genes (Basel) 2024; 15:808. [PMID: 38927743 PMCID: PMC11203369 DOI: 10.3390/genes15060808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 06/10/2024] [Accepted: 06/15/2024] [Indexed: 06/28/2024] Open
Abstract
Ionizing radiation (IR) and chemotherapy with DNA-damaging drugs such as cisplatin are vital cancer treatment options. These treatments induce double-strand breaks (DSBs) as cytotoxic DNA damage; thus, the DSB repair activity in each cancer cell significantly influences the efficacy of the treatments. Pancreatic cancers are known to be resistant to these treatments, and the overexpression of MUC1, a member of the glycoprotein mucins, is associated with IR- and chemo-resistance. Therefore, we investigated the impact of MUC1 on DSB repair. This report examined the effect of the overexpression of MUC1 on homologous recombination (HR) and non-homologous end-joining (NHEJ) using cell-based DSB repair assays. In addition, the therapeutic potential of NHEJ inhibitors including HDAC inhibitors was also studied using pancreatic cancer cell lines. The MUC1-overexpression enhances NHEJ, while partially suppressing HR. Also, MUC1-overexpressed cancer cell lines are preferentially killed by a DNA-PK inhibitor and HDAC1/2 inhibitors. Altogether, MUC1 induces metabolic changes that create an imbalance between NHEJ and HR activities, and this imbalance can be a target for selective killing by HDAC inhibitors. This is a novel mechanism of MUC1-mediated IR-resistance and will form the basis for targeting MUC1-overexpressed pancreatic cancer.
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Affiliation(s)
- Tadayoshi Bessho
- The Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, 986805 Nebraska Medical Center, Omaha, NE 68198, USA
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2
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Liu Z, Feng C, Li C, He T, Wu G, Fu C, Li H, Shen M, Liu H. IGF-I protects porcine granulosa cells from hypoxia-induced apoptosis by promoting homologous recombination repair through the PI3K/AKT/E2F8/RAD51 pathway. FASEB J 2024; 38:e23332. [PMID: 38095232 DOI: 10.1096/fj.202301464r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 10/27/2023] [Accepted: 11/13/2023] [Indexed: 12/18/2023]
Abstract
Severe hypoxia induced by vascular compromise (ovarian torsion, surgery), obliteration of vessels (aging, chemotherapy, particularly platinum drugs) can cause massive follicle atresia. On the other hand, hypoxia increases the occurrence of DNA double-strand breaks (DSBs) and triggers cellular damage repair mechanisms; however, if the damage is not promptly repaired, it can also induce the apoptosis program. Insulin-like growth factor-I (IGF-I) is a polypeptide hormone that plays essential roles in stimulating mammalian follicular development. Here, we report a novel role for IGF-I in protecting hypoxic GCs from apoptosis by promoting DNA repair through the homologous recombination (HR) process. Indeed, the hypoxic environment within follicles significantly inhibited the efficiency of HR-directed DNA repair. The presence of IGF-I-induced HR pathway to alleviate hypoxia-induced DNA damage and apoptosis primarily through upregulating the expression of the RAD51 recombinase. Importantly, we identified a new transcriptional regulator of RAD51, namely E2F8, which mediates the protective effects of IGF-I on hypoxic GCs by facilitating the transcriptional activation of RAD51. Furthermore, we demonstrated that the PI3K/AKT pathway is crucial for IGF-I-induced E2F8 expression, resulting in increased RAD51 expression and enhanced HR activity, which mitigates hypoxia-induced DNA damage and thereby protects against GCs apoptosis. Together, these findings define a novel mechanism of IGF-I-mediated GCs protection by activating the HR repair through the PI3K/AKT/E2F8/RAD51 pathway under hypoxia.
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Affiliation(s)
- Zhaojun Liu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Chungang Feng
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Chengyu Li
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Tong He
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Gang Wu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Chen Fu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Hongmin Li
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Ming Shen
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Honglin Liu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
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Chen Z, Han F, Du Y, Shi H, Zhou W. Hypoxic microenvironment in cancer: molecular mechanisms and therapeutic interventions. Signal Transduct Target Ther 2023; 8:70. [PMID: 36797231 PMCID: PMC9935926 DOI: 10.1038/s41392-023-01332-8] [Citation(s) in RCA: 120] [Impact Index Per Article: 120.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 12/20/2022] [Accepted: 01/18/2023] [Indexed: 02/18/2023] Open
Abstract
Having a hypoxic microenvironment is a common and salient feature of most solid tumors. Hypoxia has a profound effect on the biological behavior and malignant phenotype of cancer cells, mediates the effects of cancer chemotherapy, radiotherapy, and immunotherapy through complex mechanisms, and is closely associated with poor prognosis in various cancer patients. Accumulating studies have demonstrated that through normalization of the tumor vasculature, nanoparticle carriers and biocarriers can effectively increase the oxygen concentration in the tumor microenvironment, improve drug delivery and the efficacy of radiotherapy. They also increase infiltration of innate and adaptive anti-tumor immune cells to enhance the efficacy of immunotherapy. Furthermore, drugs targeting key genes associated with hypoxia, including hypoxia tracers, hypoxia-activated prodrugs, and drugs targeting hypoxia-inducible factors and downstream targets, can be used for visualization and quantitative analysis of tumor hypoxia and antitumor activity. However, the relationship between hypoxia and cancer is an area of research that requires further exploration. Here, we investigated the potential factors in the development of hypoxia in cancer, changes in signaling pathways that occur in cancer cells to adapt to hypoxic environments, the mechanisms of hypoxia-induced cancer immune tolerance, chemotherapeutic tolerance, and enhanced radiation tolerance, as well as the insights and applications of hypoxia in cancer therapy.
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Affiliation(s)
- Zhou Chen
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China.,The First Hospital of Lanzhou University, Lanzhou, Gansu, China
| | - Fangfang Han
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China.,The First Hospital of Lanzhou University, Lanzhou, Gansu, China
| | - Yan Du
- The Second Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China
| | - Huaqing Shi
- The Second Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China
| | - Wence Zhou
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China. .,Lanzhou University Sencond Hospital, Lanzhou, Gansu, China.
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Ramón-Landreau M, Sánchez-Puelles C, López-Sánchez N, Lozano-Ureña A, Llabrés-Mas AM, Frade JM. E2F4DN Transgenic Mice: A Tool for the Evaluation of E2F4 as a Therapeutic Target in Neuropathology and Brain Aging. Int J Mol Sci 2022; 23:ijms232012093. [PMID: 36292945 PMCID: PMC9603043 DOI: 10.3390/ijms232012093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/04/2022] [Accepted: 10/05/2022] [Indexed: 12/03/2022] Open
Abstract
E2F4 was initially described as a transcription factor with a key function in the regulation of cell quiescence. Nevertheless, a number of recent studies have established that E2F4 can also play a relevant role in cell and tissue homeostasis, as well as tissue regeneration. For these non-canonical functions, E2F4 can also act in the cytoplasm, where it is able to interact with many homeostatic and synaptic regulators. Since E2F4 is expressed in the nervous system, it may fulfill a crucial role in brain function and homeostasis, being a promising multifactorial target for neurodegenerative diseases and brain aging. The regulation of E2F4 is complex, as it can be chemically modified through acetylation, from which we present evidence in the brain, as well as methylation, and phosphorylation. The phosphorylation of E2F4 within a conserved threonine motif induces cell cycle re-entry in neurons, while a dominant negative form of E2F4 (E2F4DN), in which the conserved threonines have been substituted by alanines, has been shown to act as a multifactorial therapeutic agent for Alzheimer’s disease (AD). We generated transgenic mice neuronally expressing E2F4DN. We have recently shown using this mouse strain that expression of E2F4DN in 5xFAD mice, a known murine model of AD, improved cognitive function, reduced neuronal tetraploidization, and induced a transcriptional program consistent with modulation of amyloid-β (Aβ) peptide proteostasis and brain homeostasis recovery. 5xFAD/E2F4DN mice also showed reduced microgliosis and astrogliosis in both the cerebral cortex and hippocampus at 3-6 months of age. Here, we analyzed the immune response in 1 year-old 5xFAD/E2F4DN mice, concluding that reduced microgliosis and astrogliosis is maintained at this late stage. In addition, the expression of E2F4DN also reduced age-associated microgliosis in wild-type mice, thus stressing its role as a brain homeostatic agent. We conclude that E2F4DN transgenic mice represent a promising tool for the evaluation of E2F4 as a therapeutic target in neuropathology and brain aging.
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Affiliation(s)
- Morgan Ramón-Landreau
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
| | - Cristina Sánchez-Puelles
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
| | - Noelia López-Sánchez
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
| | - Anna Lozano-Ureña
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
| | - Aina M. Llabrés-Mas
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
| | - José M. Frade
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Consejo Superior de Investigaciones Científicas, 28002 Madrid, Spain
- Cajal International Neuroscience Center, Consejo Superior de Investigaciones Científicas, UAH Science and Technology Campus, Avenida León 1, 28805 Alcalá de Henares, Spain
- Correspondence: ; Tel.: +34-91-585-4740
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Xu F, Zou C, Gao Y, Shen J, Liu T, He Q, Li S, Xu S. Comprehensive analyses identify RIPOR2 as a genomic instability-associated immune prognostic biomarker in cervical cancer. Front Immunol 2022; 13:930488. [PMID: 36091054 PMCID: PMC9458976 DOI: 10.3389/fimmu.2022.930488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 08/05/2022] [Indexed: 12/14/2022] Open
Abstract
Cervical cancer (CC) is a malignancy that tends to have a poor prognosis when detected at an advanced stage; however, there are few studies on the early detection of CC at the genetic level. The tumor microenvironment (TME) and genomic instability (GI) greatly affect the survival of tumor patients via effects on carcinogenesis, tumor growth, and resistance. It is necessary to identify biomarkers simultaneously correlated with components of the TME and with GI, as these could predict the survival of patients and the efficacy of immunotherapy. In this study, we extracted somatic mutational data and transcriptome information of CC cases from The Cancer Genome Atlas, and the GSE44001 dataset from the Gene Expression Omnibus database was downloaded for external verification. Stromal components differed most between genomic unstable and genomic stable groups. Differentially expressed genes were screened out on the basis of GI and StromalScore, using somatic mutation information and ESTIMATE methods. We obtained the intersection of GI- and StromalScore-related genes and used them to establish a four-gene signature comprising RIPOR2, CCL22, PAMR1, and FBN1 for prognostic prediction. We described immunogenomic characteristics using this risk model, with methods including CIBERSORT, gene set enrichment analysis (GSEA), and single-sample GSEA. We further explored the protective factor RIPOR2, which has a close relationship with ImmuneScore. A series of in vitro experiments, including immunohistochemistry, immunofluorescence, quantitative reverse transcription PCR, transwell assay, CCK8 assay, EdU assay, cell cycle detection, colony formation assay, and Western blotting were performed to validate RIPOR2 as an anti-tumor signature. Combined with integrative bioinformatic analyses, these experiments showed a strong relationship between RIPOR2 with tumor mutation burden, expression of genes related to DNA damage response (especially PARP1), TME-related scores, activation of immune checkpoint activation, and efficacy of immunotherapy. To summarize, RIPOR2 was successfully identified through comprehensive analyses of the TME and GI as a potential biomarker for forecasting the prognosis and immunotherapy response, which could guide clinical strategies for the treatment of CC patients.
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Affiliation(s)
- Fangfang Xu
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Chang Zou
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yueqing Gao
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Jiacheng Shen
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Tingwei Liu
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Qizhi He
- Department of Pathology, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
- *Correspondence: Shaohua Xu, ; Shuangdi Li, ; Qizhi He,
| | - Shuangdi Li
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
- *Correspondence: Shaohua Xu, ; Shuangdi Li, ; Qizhi He,
| | - Shaohua Xu
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
- *Correspondence: Shaohua Xu, ; Shuangdi Li, ; Qizhi He,
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The Breast Cancer Protooncogenes HER2, BRCA1 and BRCA2 and Their Regulation by the iNOS/NOS2 Axis. Antioxidants (Basel) 2022; 11:antiox11061195. [PMID: 35740092 PMCID: PMC9227079 DOI: 10.3390/antiox11061195] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 06/01/2022] [Accepted: 06/06/2022] [Indexed: 02/04/2023] Open
Abstract
The expression of inducible nitric oxide synthase (iNOS; NOS2) and derived NO in various cancers was reported to exert pro- and anti-tumorigenic effects depending on the levels of expression and the tumor types. In humans, the breast cancer level of iNOS was reported to be overexpressed, to exhibit pro-tumorigenic activities, and to be of prognostic significance. Likewise, the expression of the oncogenes HER2, BRCA1, and BRCA2 has been associated with malignancy. The interrelationship between the expression of these protooncogenes and oncogenes and the expression of iNOS is not clear. We have hypothesized that there exist cross-talk signaling pathways between the breast cancer protooncogenes, the iNOS axis, and iNOS-mediated NO mutations of these protooncogenes into oncogenes. We review the molecular regulation of the expression of the protooncogenes in breast cancer and their interrelationships with iNOS expression and activities. In addition, we discuss the roles of iNOS, HER2, BRCA1/2, and NO metabolism in the pathophysiology of cancer stem cells. Bioinformatic analyses have been performed and have found suggested molecular alterations responsible for breast cancer aggressiveness. These include the association of BRCA1/2 mutations and HER2 amplifications with the dysregulation of the NOS pathway. We propose that future studies should be undertaken to investigate the regulatory mechanisms underlying the expression of iNOS and various breast cancer oncogenes, with the aim of identifying new therapeutic targets for the treatment of breast cancers that are refractory to current treatments.
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7
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Budke B, Zhong A, Sullivan K, Park C, Gittin DI, Kountz TS, Connell PP. Noncanonical NF-κB factor p100/p52 regulates homologous recombination and modulates sensitivity to DNA-damaging therapy. Nucleic Acids Res 2022; 50:6251-6263. [PMID: 35689636 PMCID: PMC9226503 DOI: 10.1093/nar/gkac491] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/17/2022] [Accepted: 05/25/2022] [Indexed: 11/14/2022] Open
Abstract
Homologous recombination (HR) serves multiple roles in DNA repair that are essential for maintaining genomic stability, including double-strand DNA break (DSB) repair. The central HR protein, RAD51, is frequently overexpressed in human malignancies, thereby elevating HR proficiency and promoting resistance to DNA-damaging therapies. Here, we find that the non-canonical NF-κB factors p100/52, but not RelB, control the expression of RAD51 in various human cancer subtypes. While p100/p52 depletion inhibits HR function in human tumor cells, it does not significantly influence the proficiency of non-homologous end joining, the other key mechanism of DSB repair. Clonogenic survival assays were performed using a pair DLD-1 cell lines that differ only in their expression of the key HR protein BRCA2. Targeted silencing of p100/p52 sensitizes the HR-competent cells to camptothecin, while sensitization is absent in HR-deficient control cells. These results suggest that p100/p52-dependent signaling specifically controls HR activity in cancer cells. Since non-canonical NF-κB signaling is known to be activated after various forms of genomic crisis, compensatory HR upregulation may represent a natural consequence of DNA damage. We propose that p100/p52-dependent signaling represents a promising oncologic target in combination with DNA-damaging treatments.
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Affiliation(s)
- Brian Budke
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL, USA
| | - Alison Zhong
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL, USA
| | - Katherine Sullivan
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL, USA
| | - Chanyoung Park
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL, USA
| | - David I Gittin
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL, USA
| | - Timothy S Kountz
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL, USA
| | - Philip P Connell
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL, USA
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Kyo S, Kanno K, Takakura M, Yamashita H, Ishikawa M, Ishibashi T, Sato S, Nakayama K. Clinical Landscape of PARP Inhibitors in Ovarian Cancer: Molecular Mechanisms and Clues to Overcome Resistance. Cancers (Basel) 2022; 14:cancers14102504. [PMID: 35626108 PMCID: PMC9139943 DOI: 10.3390/cancers14102504] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/17/2022] [Accepted: 05/18/2022] [Indexed: 02/04/2023] Open
Abstract
Simple Summary Recent development of maintenance therapy using PARP inhibitors in ovarian cancer has led to a significant improvement in survival rates. However, resistance to these inhibitors can occur in patients, causing disease progression or relapse. Consequently, novel treatment strategies are urgently needed to overcome this resistance. This review article focuses on the precise molecular mechanisms by which PARP inhibitors exert their antitumor effects, as well as how they elicit resistance, in order to gain insight into novel therapeutic approaches to overcome PARP inhibitor resistance in ovarian cancer. Abstract The survival of patients with advanced or recurrent ovarian cancer has improved tremendously in the past decade, mainly due to the establishment of maintenance therapy with poly (ADP-ribose) polymerase (PARP) inhibitors (PARPis) after conservative chemotherapies. Despite their superior efficacy, resistance to PARPis has been reported, and patients with resistance have a much worse prognosis. Therefore, the development of novel treatment strategies to overcome PARPi resistance is urgently needed. The present review article focuses on the molecular mechanisms of how PARPis exert cytotoxic effects on cancer cells through DNA repair processes, especially the genetic background and tumor microenvironment favored by PARPis. Furthermore, currently available information on PARPi resistance mechanisms is introduced and discussed to develop a novel therapeutic approach against them.
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Affiliation(s)
- Satoru Kyo
- Department of Obstetrics and Gynecology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan; (K.K.); (H.Y.); (M.I.); (T.I.); (S.S.); (K.N.)
- Correspondence: ; Fax: +81-(0)853-20-2264
| | - Kosuke Kanno
- Department of Obstetrics and Gynecology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan; (K.K.); (H.Y.); (M.I.); (T.I.); (S.S.); (K.N.)
| | - Masahiro Takakura
- Department of Obstetrics and Gynecology, Kanazawa Medical University, Kanazawa 920-0293, Japan;
| | - Hitomi Yamashita
- Department of Obstetrics and Gynecology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan; (K.K.); (H.Y.); (M.I.); (T.I.); (S.S.); (K.N.)
| | - Masako Ishikawa
- Department of Obstetrics and Gynecology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan; (K.K.); (H.Y.); (M.I.); (T.I.); (S.S.); (K.N.)
| | - Tomoka Ishibashi
- Department of Obstetrics and Gynecology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan; (K.K.); (H.Y.); (M.I.); (T.I.); (S.S.); (K.N.)
| | - Seiya Sato
- Department of Obstetrics and Gynecology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan; (K.K.); (H.Y.); (M.I.); (T.I.); (S.S.); (K.N.)
| | - Kentaro Nakayama
- Department of Obstetrics and Gynecology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan; (K.K.); (H.Y.); (M.I.); (T.I.); (S.S.); (K.N.)
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Dow J, Krysztofiak A, Liu Y, Colon-Rios DA, Rogers FA, Glazer PM. Vulnerability of IDH1-Mutant Cancers to Histone Deacetylase Inhibition via Orthogonal Suppression of DNA Repair. Mol Cancer Res 2021; 19:2057-2067. [PMID: 34535560 PMCID: PMC8642278 DOI: 10.1158/1541-7786.mcr-21-0456] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/06/2021] [Accepted: 09/10/2021] [Indexed: 11/16/2022]
Abstract
Exploitation of DNA repair defects has enabled major advances in treating specific cancers. Recent work discovered that the oncometabolite 2-hydroxyglutarate (2-HG), produced by neomorphic isocitrate dehydrogenase 1/2 (IDH1/2) mutations, confers a homology-directed repair (HDR) defect through 2-HG-induced histone hypermethylation masking HDR signaling. Here, we report that IDH1-mutant cancer cells are profoundly sensitive to the histone deacetylase inhibitor (HDACi) vorinostat, by further suppressing the residual HDR in 2-HG-producing cells. Vorinostat downregulates repair factors BRCA1 and RAD51 via disrupted E2F-factor regulation, causing increased DNA double-strand breaks, reduced DNA repair factor foci, and functional HDR deficiency even beyond 2-HG's effects. This results in greater cell death of IDH1-mutant cells and confers synergy with radiation and PARPi, both against cells in culture and patient-derived tumor xenografts. Our work identifies HDACi's utility against IDH1-mutant cancers, and presents IDH1/2 mutations as potential biomarkers to guide trials testing HDACi in gliomas and other malignancies. IMPLICATIONS: IDH1-mutant cells show profound vulnerability to HDACi treatment, alone and with PARPi and radiation, via HDR suppression, presenting IDH1/2 mutations as biomarkers for HDACi use in gliomas and other malignancies.
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Affiliation(s)
- Jonathan Dow
- Department of Therapeutic Radiology, Yale University School of Medicine. New Haven, Connecticut
- Department of Genetics, Yale University School of Medicine. New Haven, Connecticut
| | - Adam Krysztofiak
- Department of Therapeutic Radiology, Yale University School of Medicine. New Haven, Connecticut
| | - Yanfeng Liu
- Department of Therapeutic Radiology, Yale University School of Medicine. New Haven, Connecticut
- Department of Genetics, Yale University School of Medicine. New Haven, Connecticut
| | - Daniel A Colon-Rios
- Department of Therapeutic Radiology, Yale University School of Medicine. New Haven, Connecticut
| | - Faye A Rogers
- Department of Therapeutic Radiology, Yale University School of Medicine. New Haven, Connecticut
| | - Peter M Glazer
- Department of Therapeutic Radiology, Yale University School of Medicine. New Haven, Connecticut.
- Department of Genetics, Yale University School of Medicine. New Haven, Connecticut
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10
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Therapeutic targeting of the hypoxic tumour microenvironment. Nat Rev Clin Oncol 2021; 18:751-772. [PMID: 34326502 DOI: 10.1038/s41571-021-00539-4] [Citation(s) in RCA: 173] [Impact Index Per Article: 57.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2021] [Indexed: 02/07/2023]
Abstract
Hypoxia is prevalent in human tumours and contributes to microenvironments that shape cancer evolution and adversely affect therapeutic outcomes. Historically, two different tumour microenvironment (TME) research communities have been discernible. One has focused on physicochemical gradients of oxygen, pH and nutrients in the tumour interstitium, motivated in part by the barrier that hypoxia poses to effective radiotherapy. The other has focused on cellular interactions involving tumour and non-tumour cells within the TME. Over the past decade, strong links have been established between these two themes, providing new insights into fundamental aspects of tumour biology and presenting new strategies for addressing the effects of hypoxia and other microenvironmental features that arise from the inefficient microvascular system in solid tumours. This Review provides a perspective on advances at the interface between these two aspects of the TME, with a focus on translational therapeutic opportunities relating to the elimination and/or exploitation of tumour hypoxia.
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11
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Radiosensitisation of SCCVII tumours and normal tissues in mice by the DNA-dependent protein kinase inhibitor AZD7648. Radiother Oncol 2021; 166:162-170. [PMID: 34861268 DOI: 10.1016/j.radonc.2021.11.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 10/18/2021] [Accepted: 11/22/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND PURPOSE Inhibitors of DNA-dependent protein kinase (DNA-PK) are effective radiation sensitisers in preclinical tumours, but little is known about risks of normal tissue radiosensitisation. Here, we evaluate radiosensitisation of head and neck squamous cell carcinoma (HNSCC) cells by DNA-PK inhibitor AZD7648 under oxia and anoxia in vitro, and tumour (SCCVII), oral mucosa and small intestine in mice. MATERIALS AND METHODS Radiosensitisation of human (UT-SCC-54C) and murine (SCCVII) HNSCC cells by AZD7648 under oxia and anoxia was evaluated by clonogenic assay. Radiosensitisation of SCCVII tumours in C3H mice by oral AZD7648 (75 mg/kg) was determined by ex vivo clonogenic assay 3.5 days post-irradiation, with evaluation of normal tissue surrogate endpoints using 5-ethynyl-2'-deoxyuridine to facilitate detection of regenerating crypts in the ileum and repopulating S-phase cells in the ileum and oral mucosa of the same animals. RESULTS AZD7648 potently radiosensitised both cell lines, with similar sensitiser enhancement ratios for 10% survival (SER10) under oxia and anoxia. AZD7648 diffused rapidly through multicellular layers, suggesting rapid equilibration between plasma and hypoxic zones in tumours. SCCVII tumours were radiosensitised by AZD7648 (SER10 2.5). AZD7648 also enhanced radiation-induced body weight loss and suppressed regenerating intestinal crypts and repopulating S-phase cells in the ileum and tongue epithelium with SER values similar to SCCVII tumours. CONCLUSION AZD7648 is a potent radiation sensitiser of both oxic and anoxic tumour cells, but also markedly radiosensitises stem cells in the small intestine and oral mucosa.
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Bakr A, Hey J, Sigismondo G, Liu CS, Sadik A, Goyal A, Cross A, Iyer RL, Müller P, Trauernicht M, Breuer K, Lutsik P, Opitz C, Krijgsveld J, Weichenhan D, Plass C, Popanda O, Schmezer P. ID3 promotes homologous recombination via non-transcriptional and transcriptional mechanisms and its loss confers sensitivity to PARP inhibition. Nucleic Acids Res 2021; 49:11666-11689. [PMID: 34718742 PMCID: PMC8599806 DOI: 10.1093/nar/gkab964] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/23/2021] [Accepted: 10/05/2021] [Indexed: 12/13/2022] Open
Abstract
The inhibitor of DNA-binding 3 (ID3) is a transcriptional regulator that limits interaction of basic helix-loop-helix transcription factors with their target DNA sequences. We previously reported that ID3 loss is associated with mutational signatures linked to DNA repair defects. Here we demonstrate that ID3 exhibits a dual role to promote DNA double-strand break (DSB) repair, particularly homologous recombination (HR). ID3 interacts with the MRN complex and RECQL helicase to activate DSB repair and it facilitates RAD51 loading and downstream steps of HR. In addition, ID3 promotes the expression of HR genes in response to ionizing radiation by regulating both chromatin accessibility and activity of the transcription factor E2F1. Consistently, analyses of TCGA cancer patient data demonstrate that low ID3 expression is associated with impaired HR. The loss of ID3 leads to sensitivity of tumor cells to PARP inhibition, offering new therapeutic opportunities in ID3-deficient tumors.
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Affiliation(s)
- Ali Bakr
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Joschka Hey
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
- Heidelberg University, Faculty of Biosciences, 69120 Heidelberg, Germany
| | - Gianluca Sigismondo
- Division of Proteomics of Stem Cells and Cancer, German Cancer Research Center (DKFZ), INF581, 69120 Heidelberg, Germany
| | - Chun-Shan Liu
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Ahmed Sadik
- DKTK Brain Cancer Metabolism Group, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Ashish Goyal
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Alice Cross
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
- Imperial College London, London, SW7 2AZ, UK
| | - Ramya Lakshmana Iyer
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Patrick Müller
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Max Trauernicht
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Kersten Breuer
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Pavlo Lutsik
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Christiane A Opitz
- DKTK Brain Cancer Metabolism Group, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Neurology Clinic and National Center for Tumor Diseases, Heidelberg University Hospital, 69120 Heidelberg, Germany
| | - Jeroen Krijgsveld
- Division of Proteomics of Stem Cells and Cancer, German Cancer Research Center (DKFZ), INF581, 69120 Heidelberg, Germany
- Heidelberg University, Medical Faculty, INF672, 69120, Heidelberg, Germany
| | - Dieter Weichenhan
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Christoph Plass
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), INF280, 69120 Heidelberg, Germany
| | - Odilia Popanda
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
| | - Peter Schmezer
- Division of Cancer Epigenomics, German Cancer Research Center (DKFZ), INF280, 69120 Heidelberg, Germany
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Direct targeting of amplified gene loci for proapoptotic anticancer therapy. Nat Biotechnol 2021; 40:325-334. [PMID: 34711990 PMCID: PMC8930417 DOI: 10.1038/s41587-021-01057-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 08/05/2021] [Indexed: 12/16/2022]
Abstract
Gene amplification drives oncogenesis in a broad spectrum of cancers. A number of drugs have been developed to inhibit the protein products of amplified driver genes, but their clinical efficacy is often hampered by drug resistance. Here, we introduce a therapeutic strategy for targeting cancer-associated gene amplifications by activating the DNA damage response with triplex-forming oligonucleotides (TFOs), which drives induction of apoptosis in tumors, whereas cells without amplifications process lower levels of DNA damage. Focusing on cancers driven by HER2-amplification, we find that TFOs targeting HER2 induce copy number-dependent DNA double strand breaks and activate p53-independent apoptosis in HER2-positive cancer cells and human tumor xenografts via a mechanism that is independent of HER2 cellular function. This strategy has demonstrated in vivo efficacy comparable with current precision medicines and provided a feasible alternative to combat drug resistance in HER-positive breast and ovarian cancer models. These findings offer a general strategy for targeting tumors with amplified genomic loci.
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14
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Jiang M, Jia K, Wang L, Li W, Chen B, Liu Y, Wang H, Zhao S, He Y, Zhou C. Alterations of DNA damage response pathway: Biomarker and therapeutic strategy for cancer immunotherapy. Acta Pharm Sin B 2021; 11:2983-2994. [PMID: 34729299 PMCID: PMC8546664 DOI: 10.1016/j.apsb.2021.01.003] [Citation(s) in RCA: 115] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/25/2020] [Accepted: 11/03/2020] [Indexed: 12/24/2022] Open
Abstract
Genomic instability remains an enabling feature of cancer and promotes malignant transformation. Alterations of DNA damage response (DDR) pathways allow genomic instability, generate neoantigens, upregulate the expression of programmed death ligand 1 (PD-L1) and interact with signaling such as cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) signaling. Here, we review the basic knowledge of DDR pathways, mechanisms of genomic instability induced by DDR alterations, impacts of DDR alterations on immune system, and the potential applications of DDR alterations as biomarkers and therapeutic targets in cancer immunotherapy.
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Key Words
- ATM, ataxia-telangiectasia mutated
- ATR, ataxia telangiectasia and Rad3 related
- BAP1, BRCA1-associated protein 1
- BER, base excision repair
- BRAF, v-RAF murine sarcoma viral oncogene homologue B
- BRCA, breast cancer susceptibility gene
- CHEK, cell-cycle checkpoint kinase
- CHK1, checkpoint kinase 1
- DAMP, damage-associated molecular patterns
- DDR, DNA damage response
- DNA damage response
- DNA repair
- DR, direct repair
- DSBs, double-strand breaks
- FDA, United State Food and Drug Administration
- GSK3β, glycogen synthase kinase 3β
- Genomic instability
- HMGB1, high mobility group box-1
- HRR, homologous recombination repair
- ICI, immune checkpoint inhibitor
- IFNγ, interferon gamma
- IHC, immunohistochemistry
- IRF1, interferon regulatory factor 1
- Immunotherapy
- JAK, Janus kinase
- MAD1, mitotic arrest deficient-like 1
- MGMT, O6-methylguanine methyltransferase
- MLH1, MutL homolog 1
- MMR, mismatch repair
- MNT, MAX network transcriptional repressor
- MSH2/6, MutS protein homologue-2/6
- MSI, microsatellite instability
- MUTYH, MutY homolog
- MyD88, myeloid differentiation factor 88
- NEK1, NIMA-related kinase 1
- NER, nucleotide excision repair
- NGS, next generation sequencing
- NHEJ, nonhomologous end-joining
- NIMA, never-in-mitosis A
- NSCLC, non-small cell lung cancer
- ORR, objective response rate
- OS, overall survival
- PALB2, partner and localizer of BRCA2
- PARP, poly-ADP ribose polymerase
- PCR, polymerase chain reaction
- PD-1
- PD-1, programmed death 1
- PD-L1
- PD-L1, programmed death ligand 1
- PFS, progression-free survival
- RAD51C, RAD51 homolog C
- RB1, retinoblastoma 1
- RPA, replication protein A
- RSR, replication stress response
- SCNAs, somatic copy number alterations
- STAT, signal transducer and activator of transcription
- STING, stimulator of interferon genes
- TBK1, TANK-binding kinase 1
- TILs, tumor-infiltrating lymphocytes
- TLR4, Toll-like receptor 4
- TMB, tumor mutational burden
- TME, tumor microenvironment
- TP53, tumor protein P53
- TRIF, Toll-interleukin 1 receptor domain-containing adaptor inducing INF-β
- Tumor microenvironment
- XRCC4, X-ray repair cross complementing protein 4
- cGAS, cyclic GMP–AMP synthase
- cGAS–STING
- ssDNA, single-stranded DNA
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Affiliation(s)
- Minlin Jiang
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
- Medical School, Tongji University, Shanghai 200433, China
| | - Keyi Jia
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
- Medical School, Tongji University, Shanghai 200433, China
| | - Lei Wang
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
| | - Wei Li
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
| | - Bin Chen
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
| | - Yu Liu
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
- Medical School, Tongji University, Shanghai 200433, China
| | - Hao Wang
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
- Medical School, Tongji University, Shanghai 200433, China
| | - Sha Zhao
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
| | - Yayi He
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
| | - Caicun Zhou
- Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai 200433, China
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Orhan E, Velazquez C, Tabet I, Sardet C, Theillet C. Regulation of RAD51 at the Transcriptional and Functional Levels: What Prospects for Cancer Therapy? Cancers (Basel) 2021; 13:2930. [PMID: 34208195 PMCID: PMC8230762 DOI: 10.3390/cancers13122930] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 01/07/2023] Open
Abstract
The RAD51 recombinase is a critical effector of Homologous Recombination (HR), which is an essential DNA repair mechanism for double-strand breaks. The RAD51 protein is recruited onto the DNA break by BRCA2 and forms homopolymeric filaments that invade the homologous chromatid and use it as a template for repair. RAD51 filaments are detectable by immunofluorescence as distinct foci in the cell nucleus, and their presence is a read out of HR proficiency. RAD51 is an essential gene, protecting cells from genetic instability. Its expression is low and tightly regulated in normal cells and, contrastingly, elevated in a large fraction of cancers, where its level of expression and activity have been linked with sensitivity to genotoxic treatment. In particular, BRCA-deficient tumors show reduced or obliterated RAD51 foci formation and increased sensitivity to platinum salt or PARP inhibitors. However, resistance to treatment sets in rapidly and is frequently based on a complete or partial restoration of RAD51 foci formation. Consequently, RAD51 could be a highly valuable therapeutic target. Here, we review the multiple levels of regulation that impact the transcription of the RAD51 gene, as well as the post-translational modifications that determine its expression level, recruitment on DNA damage sites and the efficient formation of homofilaments. Some of these regulation levels may be targeted and their impact on cancer cell survival discussed.
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Affiliation(s)
- Esin Orhan
- IRCM, Institut de Recherche en Cancérologie de Montpellier U1194 INSERM, Université de Montpellier, 34090 Montpellier, France; (E.O.); (I.T.); (C.S.)
| | | | - Imene Tabet
- IRCM, Institut de Recherche en Cancérologie de Montpellier U1194 INSERM, Université de Montpellier, 34090 Montpellier, France; (E.O.); (I.T.); (C.S.)
| | - Claude Sardet
- IRCM, Institut de Recherche en Cancérologie de Montpellier U1194 INSERM, Université de Montpellier, 34090 Montpellier, France; (E.O.); (I.T.); (C.S.)
| | - Charles Theillet
- IRCM, Institut de Recherche en Cancérologie de Montpellier U1194 INSERM, Université de Montpellier, 34090 Montpellier, France; (E.O.); (I.T.); (C.S.)
- ICM, Institut du Cancer de Montpellier, 34090 Montpellier, France;
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16
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Cowman S, Pizer B, Sée V. Downregulation of both mismatch repair and non-homologous end-joining pathways in hypoxic brain tumour cell lines. PeerJ 2021; 9:e11275. [PMID: 33986995 PMCID: PMC8092103 DOI: 10.7717/peerj.11275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 03/24/2021] [Indexed: 01/11/2023] Open
Abstract
Glioblastoma, a grade IV astrocytoma, has a poor survival rate in part due to ineffective treatment options available. These tumours are heterogeneous with areas of low oxygen levels, termed hypoxic regions. Many intra-cellular signalling pathways, including DNA repair, can be altered by hypoxia. Since DNA damage induction and subsequent activation of DNA repair mechanisms is the cornerstone of glioblastoma treatment, alterations to DNA repair mechanisms could have a direct influence on treatment success. Our aim was to elucidate the impact of chronic hypoxia on DNA repair gene expression in a range of glioblastoma cell lines. We adopted a NanoString transcriptomic approach to examine the expression of 180 DNA repair-related genes in four classical glioblastoma cell lines (U87-MG, U251-MG, D566-MG, T98G) exposed to 5 days of normoxia (21% O2), moderate (1% O2) or severe (0.1% O2) hypoxia. We observed altered gene expression in several DNA repair pathways including homologous recombination repair, non-homologous end-joining and mismatch repair, with hypoxia primarily resulting in downregulation of gene expression. The extent of gene expression changes was dependent on hypoxic severity. Some, but not all, of these downregulations were directly under the control of HIF activity. For example, the downregulation of LIG4, a key component of non-homologous end-joining, was reversed upon inhibition of the hypoxia-inducible factor (HIF). In contrast, the downregulation of the mismatch repair gene, PMS2, was not affected by HIF inhibition. This suggests that numerous molecular mechanisms lead to hypoxia-induced reprogramming of the transcriptional landscape of DNA repair. Whilst the global impact of hypoxia on DNA repair gene expression is likely to lead to genomic instability, tumorigenesis and reduced sensitivity to anti-cancer treatment, treatment re-sensitising might require additional approaches to a simple HIF inhibition.
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Affiliation(s)
- Sophie Cowman
- Institute of Systems, Molecular and Integrative Biology, Department of Molecular Physiology and Cell Signalling, University of Liverpool, Liverpool, Merseyside, United Kingdom.,Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt-Lake-City, Utah, United States
| | - Barry Pizer
- Paediatric Oncology, Alder Hey Children's NHS Foundation Trust, Liverpool, Merseyside, United Kingdom
| | - Violaine Sée
- Institute of Systems, Molecular and Integrative Biology, Department of Molecular Physiology and Cell Signalling, University of Liverpool, Liverpool, Merseyside, United Kingdom
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17
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Hypoxia-Driven Effects in Cancer: Characterization, Mechanisms, and Therapeutic Implications. Cells 2021; 10:cells10030678. [PMID: 33808542 PMCID: PMC8003323 DOI: 10.3390/cells10030678] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/15/2021] [Accepted: 03/17/2021] [Indexed: 12/11/2022] Open
Abstract
Hypoxia, a common feature of solid tumors, greatly hinders the efficacy of conventional cancer treatments such as chemo-, radio-, and immunotherapy. The depletion of oxygen in proliferating and advanced tumors causes an array of genetic, transcriptional, and metabolic adaptations that promote survival, metastasis, and a clinically malignant phenotype. At the nexus of these interconnected pathways are hypoxia-inducible factors (HIFs) which orchestrate transcriptional responses under hypoxia. The following review summarizes current literature regarding effects of hypoxia on DNA repair, metastasis, epithelial-to-mesenchymal transition, the cancer stem cell phenotype, and therapy resistance. We also discuss mechanisms and pathways, such as HIF signaling, mitochondrial dynamics, exosomes, and the unfolded protein response, that contribute to hypoxia-induced phenotypic changes. Finally, novel therapeutics that target the hypoxic tumor microenvironment or interfere with hypoxia-induced pathways are reviewed.
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18
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Kaplan AR, Glazer PM. Impact of hypoxia on DNA repair and genome integrity. Mutagenesis 2021; 35:61-68. [PMID: 31282537 DOI: 10.1093/mutage/gez019] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 06/24/2019] [Indexed: 12/12/2022] Open
Abstract
Hypoxia is a hallmark of the tumour microenvironment with profound effects on tumour biology, influencing cancer progression, the development of metastasis and patient outcome. Hypoxia also contributes to genomic instability and mutation frequency by inhibiting DNA repair pathways. This review summarises the diverse mechanisms by which hypoxia affects DNA repair, including suppression of homology-directed repair, mismatch repair and base excision repair. We also discuss the effects of hypoxia mimetics and agents that induce hypoxia on DNA repair, and we highlight areas of potential clinical relevance as well as future directions.
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Affiliation(s)
- Alanna R Kaplan
- Department of Therapeutic Radiology, New Haven, CT, USA.,Department of Experimental Pathology, New Haven, CT, USA
| | - Peter M Glazer
- Department of Therapeutic Radiology, New Haven, CT, USA.,Department of Genetics, Yale University, New Haven, CT, USA
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19
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Rakotomalala A, Escande A, Furlan A, Meignan S, Lartigau E. Hypoxia in Solid Tumors: How Low Oxygenation Impacts the "Six Rs" of Radiotherapy. Front Endocrinol (Lausanne) 2021; 12:742215. [PMID: 34539584 PMCID: PMC8445158 DOI: 10.3389/fendo.2021.742215] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 08/13/2021] [Indexed: 12/11/2022] Open
Abstract
Radiotherapy is an important component of cancer treatment, with approximately 50% of all cancer patients receiving radiation therapy during their course of illness. Nevertheless, solid tumors frequently exhibit hypoxic areas, which can hinder therapies efficacy, especially radiotherapy one. Indeed, hypoxia impacts the six parameters governing the radiotherapy response, called the « six Rs of radiation biology » (for Radiosensitivity, Repair, Repopulation, Redistribution, Reoxygenation, and Reactivation of anti-tumor immune response), by inducing pleiotropic cellular adaptions, such as cell metabolism rewiring, epigenetic landscape remodeling, and cell death weakening, with significant clinical repercussions. In this review, according to the six Rs, we detail how hypoxia, and associated mechanisms and pathways, impact the radiotherapy response of solid tumors and the resulting clinical implications. We finally illustrate it in hypoxic endocrine cancers through a focus on anaplastic thyroid carcinomas.
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Affiliation(s)
- Andria Rakotomalala
- Oscar Lambret center, Tumorigenesis and Resistance to Treatment Unit, Lille, France
- Univ. Lille, CNRS, Inserm, CHU Lille, UMR9020-U1277 - CANTHER – Cancer Heterogeneity Plasticity and Resistance to Therapies, Lille, France
| | - Alexandre Escande
- Oscar Lambret Center, Academic Radiation Oncology Department, Lille, France
- University of Lille, H. Warembourg School of Medicine, Lille, France
- CRIStAL UMR CNRS 9189, University of Lille, Villeneuve-d’Ascq, France
| | - Alessandro Furlan
- Oscar Lambret center, Tumorigenesis and Resistance to Treatment Unit, Lille, France
- Univ. Lille, CNRS, Inserm, CHU Lille, UMR9020-U1277 - CANTHER – Cancer Heterogeneity Plasticity and Resistance to Therapies, Lille, France
| | - Samuel Meignan
- Oscar Lambret center, Tumorigenesis and Resistance to Treatment Unit, Lille, France
- Univ. Lille, CNRS, Inserm, CHU Lille, UMR9020-U1277 - CANTHER – Cancer Heterogeneity Plasticity and Resistance to Therapies, Lille, France
- *Correspondence: Samuel Meignan,
| | - Eric Lartigau
- Oscar Lambret Center, Academic Radiation Oncology Department, Lille, France
- University of Lille, H. Warembourg School of Medicine, Lille, France
- CRIStAL UMR CNRS 9189, University of Lille, Villeneuve-d’Ascq, France
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20
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Gou R, Dong H, Lin B. Application and reflection of genomic scar assays in evaluating the efficacy of platinum salts and PARP inhibitors in cancer therapy. Life Sci 2020; 261:118434. [PMID: 32941897 DOI: 10.1016/j.lfs.2020.118434] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 09/05/2020] [Accepted: 09/11/2020] [Indexed: 12/24/2022]
Abstract
Defective DNA repair is one of the most important features of tumors. BRCA1/2 participates in homologous recombination repair as a key tumor suppressor gene. BRCA1/2 mutation is an important biomarker for predicting the sensitivity of platinum salts and Poly (ADP-ribose) polymerase (PARP) inhibitors in breast cancer, ovarian cancer, and other cancers. However, epigenetic modifications and other mutations in homologous recombination repair (HRR) genes can also cause homologous recombination deficiency (HRD). Patients with no BRCA1/2 mutations, but bearing similar molecular phenotypes (BRCAness) can still obtain clinical benefits from treatment with platinum salts or PARP inhibitors. Therefore, an accurate assessment of HRD is essential for the formulation of personalized treatments. However, methods to identify HRD in tumors vary and are controversial. Currently, genomic scar assays have been used in multiple clinical trials to assess patient clinical benefit. This review summarizes the therapeutic effects of platinum salts and PARP inhibitors in breast and ovarian cancer, clarifies the predictive value of genomic scar assays in evaluating the clinical benefit of different patient groups and treatment options, and proposes the limitations and optimization of current HRD scoring methods. Using and optimizing genomic scar assays can help to accurately screen the population with the most benefit, expand the scope of drug application, and make the most suitable clinical decision based on individual differences.
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Affiliation(s)
- Rui Gou
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning, China
| | - Hui Dong
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning, China
| | - Bei Lin
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning, China.
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21
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Begg K, Tavassoli M. Inside the hypoxic tumour: reprogramming of the DDR and radioresistance. Cell Death Discov 2020; 6:77. [PMID: 32864165 PMCID: PMC7434912 DOI: 10.1038/s41420-020-00311-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/27/2020] [Accepted: 04/09/2020] [Indexed: 12/19/2022] Open
Abstract
The hypoxic tumour is a chaotic landscape of struggle and adaption. Against the adversity of oxygen starvation, hypoxic cancer cells initiate a reprogramming of transcriptional activities, allowing for survival, metastasis and treatment failure. This makes hypoxia a crucial feature of aggressive tumours. Its importance, to cancer and other diseases, was recognised by the award of the 2019 Nobel Prize in Physiology or Medicine for research contributing to our understanding of the cellular response to oxygen deprivation. For cancers with limited treatment options, for example those that rely heavily on radiotherapy, the results of hypoxic adaption are particularly restrictive to treatment success. A fundamental aspect of this hypoxic reprogramming with direct relevance to radioresistance, is the alteration to the DNA damage response, a complex set of intermingling processes that guide the cell (for good or for bad) towards DNA repair or cell death. These alterations, compounded by the fact that oxygen is required to induce damage to DNA during radiotherapy, means that hypoxia represents a persistent obstacle in the treatment of many solid tumours. Considerable research has been done to reverse, correct or diminish hypoxia's power over successful treatment. Though many clinical trials have been performed or are ongoing, particularly in the context of imaging studies and biomarker discovery, this research has yet to inform clinical practice. Indeed, the only hypoxia intervention incorporated into standard of care is the use of the hypoxia-activated prodrug Nimorazole, for head and neck cancer patients in Denmark. Decades of research have allowed us to build a picture of the shift in the DNA repair capabilities of hypoxic cancer cells. A literature consensus tells us that key signal transducers of this response are upregulated, where repair proteins are downregulated. However, a complete understanding of how these alterations lead to radioresistance is yet to come.
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Affiliation(s)
- Katheryn Begg
- Head and Neck Oncology Group, Centre for Host Microbiome Interaction, King’s College London, Hodgkin Building, London, SE1 1UL UK
| | - Mahvash Tavassoli
- Head and Neck Oncology Group, Centre for Host Microbiome Interaction, King’s College London, Hodgkin Building, London, SE1 1UL UK
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22
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Khalife H, Skafi N, Fayyad-Kazan M, Badran B. MicroRNAs in breast cancer: New maestros defining the melody. Cancer Genet 2020; 246-247:18-40. [PMID: 32805688 DOI: 10.1016/j.cancergen.2020.08.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/07/2020] [Accepted: 08/03/2020] [Indexed: 02/06/2023]
Abstract
MicroRNAs, short non-coding single-stranded RNAs, are important regulators and gatekeepers of the coding genes in the human genome. MicroRNAs are highly conserved among species and expressed in different tissues and cell types. They are involved in almost all the biological processes as apoptosis, proliferation, cell cycle arrest and differentiation. Playing all these roles, it is not surprising that the deregulation of the microRNA profile causes a number of diseases including cancer. Breast cancer, the most commonly diagnosed malignancy in women, accounts for the highest cancer-related deaths worldwide. Different microRNAs were shown to be up or down regulated in breast cancer. MicroRNAs can function as oncogenes or tumor suppressors according to their targets. In this review, the most common microRNAs implicated in breast cancer are fully illustrated with their targets. Besides, the review highlights the effect of exosomal microRNA on breast cancer and the effect of microRNAs on drug and therapies resistance as well as the miRNA-based therapeutic strategies used until today.
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Affiliation(s)
- Hoda Khalife
- Laboratory of Cancer biology and Molecular Immunology, Faculty of Sciences-I, Lebanese University, Hadath, Beirut, Lebanon.
| | - Najwa Skafi
- Laboratory of Cancer biology and Molecular Immunology, Faculty of Sciences-I, Lebanese University, Hadath, Beirut, Lebanon.
| | - Mohammad Fayyad-Kazan
- Laboratory of Cancer biology and Molecular Immunology, Faculty of Sciences-I, Lebanese University, Hadath, Beirut, Lebanon; Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Beirut, Lebanon.
| | - Bassam Badran
- Laboratory of Cancer biology and Molecular Immunology, Faculty of Sciences-I, Lebanese University, Hadath, Beirut, Lebanon.
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23
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Kaplan AR, Gueble SE, Liu Y, Oeck S, Kim H, Yun Z, Glazer PM. Cediranib suppresses homology-directed DNA repair through down-regulation of BRCA1/2 and RAD51. Sci Transl Med 2020; 11:11/492/eaav4508. [PMID: 31092693 DOI: 10.1126/scitranslmed.aav4508] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 01/30/2019] [Accepted: 04/15/2019] [Indexed: 12/19/2022]
Abstract
Combining the anti-angiogenic agent cediranib with the poly(ADP-ribose) polymerase (PARP) inhibitor olaparib improves progression-free survival compared to olaparib alone in ovarian cancer patients through an unknown mechanism. PARP inhibitors are used primarily in the treatment of patients with DNA repair-associated (BRCA1/2) mutated cancers because these mutations cause a deficit in homology-directed DNA repair (HDR) that confers sensitivity to these agents. However, the combination of cediranib and olaparib was effective in patients without BRCA1/2 mutations. We report here that cediranib confers sensitivity to olaparib by down-regulating HDR in tumor cells. This occurs partially as a result of cediranib inducing hypoxia, which suppresses expression of the HDR factors BRCA1/2 and RAD51 recombinase (RAD51). However, we also observed that cediranib has a direct effect on HDR independent of its ability to induce tumor hypoxia. This direct effect occurs through platelet-derived growth factor receptor (PDGFR) inhibition, activation of protein phosphatase 2A (PP2A), and E2F transcription factor 4 (E2F4)/RB transcriptional corepressor like 2 (RB2/p130)-mediated repression of BRCA1/2 and RAD51 gene expression. This down-regulation was seen in mouse tumor xenografts but not in mouse bone marrow, providing a therapeutic window for combining cediranib and olaparib in cancer therapy. Our work reveals a treatment strategy by which DNA repair can be manipulated in human tumors to induce synthetic lethality, broadening the potential therapeutic scope of cediranib based on its activity as a DNA repair inhibitor.
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Affiliation(s)
- Alanna R Kaplan
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06511, USA.,Department of Pathology, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Susan E Gueble
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06511, USA.,Department of Pathology, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Yanfeng Liu
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Sebastian Oeck
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Hoon Kim
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Zhong Yun
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Peter M Glazer
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06511, USA. .,Department of Genetics, Yale University School of Medicine, New Haven, CT 06511, USA
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24
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Role of Rad51 and DNA repair in cancer: A molecular perspective. Pharmacol Ther 2020; 208:107492. [PMID: 32001312 DOI: 10.1016/j.pharmthera.2020.107492] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 01/13/2020] [Accepted: 01/22/2020] [Indexed: 12/24/2022]
Abstract
The maintenance of genome integrity is essential for any organism survival and for the inheritance of traits to offspring. To the purpose, cells have developed a complex DNA repair system to defend the genetic information against both endogenous and exogenous sources of damage. Accordingly, multiple repair pathways can be aroused from the diverse forms of DNA lesions, which can be effective per se or via crosstalk with others to complete the whole DNA repair process. Deficiencies in DNA healing resulting in faulty repair and/or prolonged DNA damage can lead to genes mutations, chromosome rearrangements, genomic instability, and finally carcinogenesis and/or cancer progression. Although it might seem paradoxical, at the same time such defects in DNA repair pathways may have therapeutic implications for potential clinical practice. Here we provide an overview of the main DNA repair pathways, with special focus on the role played by homologous repair and the RAD51 recombinase protein in the cellular DNA damage response. We next discuss the recombinase structure and function per se and in combination with all its principal mediators and regulators. Finally, we conclude with an analysis of the manifold roles that RAD51 plays in carcinogenesis, cancer progression and anticancer drug resistance, and conclude this work with a survey of the most promising therapeutic strategies aimed at targeting RAD51 in experimental oncology.
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25
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Pharmacological methods to transcriptionally modulate double-strand break DNA repair. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2019; 354:187-213. [PMID: 32475473 DOI: 10.1016/bs.ircmb.2019.11.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
There is much interest in targeting DNA repair pathways for use in cancer therapy, as the effectiveness of many therapeutic agents relies on their ability to cause damage to DNA, and deficiencies in DSB repair pathways can make cells more sensitive to specific cancer therapies. For example, defects in the double-strand break (DSB) pathways, non-homologous end joining (NHEJ) and homology-directed repair (HDR), induce sensitivity to radiation therapy and poly(ADP)-ribose polymerase (PARP) inhibitors, respectively. However, traditional approaches to inhibit DNA repair through small molecule inhibitors have often been limited by toxicity and poor bioavailability. This review identifies several pharmacologic manipulations that modulate DSB repair by reducing expression of DNA repair factors. A number of pathways have been identified that modulate activity of NHEJ and HDR through this mechanism, including growth and hormonal receptor signaling pathways as well as epigenetic modifiers. We also discuss the effects of anti-angiogenic therapy on DSB repair. Preclinically, these pharmacological manipulations of DNA repair factor expression have been shown to increase sensitivity to specific cancer therapies, including ionizing radiation and PARP inhibitors. When applicable, relevant clinical trials are discussed and areas for future study are identified.
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26
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Son YO. Molecular Mechanisms of Nickel-Induced Carcinogenesis. Endocr Metab Immune Disord Drug Targets 2019; 20:1015-1023. [PMID: 31774048 DOI: 10.2174/1871530319666191125112728] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/11/2019] [Accepted: 03/22/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND The increased use of heavy metal nickel in modern industries results in increased environmental impact. Occupational and environmental exposure to nickel is closely linked to an increased risk of human lung cancer and nasal cancer. OBJECTIVE Unlike other heavy metal carcinogens, nickel has weak mutagenic activity. Carcinogenesis caused by nickel is intensively studied, but the precise mechanism of action is not yet known. RESULTS Epigenetic changes, activation of hypoxia signaling pathways, and generation of reactive oxygen species (ROS) are considered to be the major molecular mechanisms involved in nickelinduced carcinogenesis. CONCLUSION This review provides insights into current research on nickel-induced carcinogenesis and suggests possible effective therapeutic strategies for nickel-induced carcinogenesis.
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Affiliation(s)
- Young-Ok Son
- Department of Animal Biotechnology, Faculty of Biotechnology and Interdisciplinary Graduate Program in Advanced Convergence Technology and Science, Jeju National University, Jeju City, Jeju Special Self-Governing Province, 63243, Korea
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27
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Lafta IJ. E2F6 is essential for cell viability in breast cancer cells during replication stress. ACTA ACUST UNITED AC 2019; 43:293-304. [PMID: 31768102 PMCID: PMC6823915 DOI: 10.3906/biy-1905-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
E2F6 is a member of the E2F family of transcription factors involved in regulation of a wide variety of genes through both activation and repression. E2F6 has been reported as overexpressed in breast cancers but whether or not this is important for tumor development is unclear. We first checked E2F6 expression in tumor cDNAs and the protein level in a range of breast cancer cell lines. RNA interference-mediated depletion was then used to assess the importance of E2F6 expression in cell lines with regard to cell cycle profile using fluorescence-activated cell sorting and a cell survival assay using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The overexpression of E2F6 was confirmed in breast tumor cDNA samples and breast cancer cell lines. Depletion of E2F6 in the breast cancer cells reduced cell viability in MCF-7, T-47D, and MDA-MB-231 cells. There was little effect in the nontumor breast cell line MCF-10A. The deleterious effect on cancer cells was greater during replication stress, leading to an increase in the proportion of breast cancer cells with sub-G1 DNA content. These results suggest that E2F6 might be essential for the survival of breast cancer cells experiencing replication stress, and therefore it could be a target for combined therapy.
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Affiliation(s)
- Inam Jasim Lafta
- Department of Microbiology, College of Veterinary Medicine, University of Baghdad, Baghdad, Iraq
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28
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Shi L, Sun J, Kinomura A, Fukuto A, Horikoshi Y, Tashiro S. Matrin3 promotes homologous recombinational repair by regulation of RAD51. J Biochem 2019; 166:343-351. [PMID: 31119278 DOI: 10.1093/jb/mvz041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 05/15/2019] [Indexed: 01/19/2023] Open
Abstract
Matrin3 is a highly conserved inner nuclear matrix protein involved in multiple stages of RNA metabolism. Although Matrin3 may also play a role in DNA repair, its precise roles have remained unclear. In this study, we showed that the depletion of Matrin3 led to decreased homologous recombination (HR) efficiency and increased radiation sensitivity of cells. Matrin3-depleted cells showed impaired DNA damage-dependent focus formation of RAD51, a key protein in HR. These findings suggest that Matrin3 promotes HR by regulating RAD51.
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Affiliation(s)
- Lin Shi
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine
| | - Jiying Sun
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine
| | - Aiko Kinomura
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine
| | - Atsuhiko Fukuto
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine
- Department of Ophthalmology and Visual Science, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Yasunori Horikoshi
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine
| | - Satoshi Tashiro
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine
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29
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Shen H, Yang ESH, Conry M, Fiveash J, Contreras C, Bonner JA, Shi LZ. Predictive biomarkers for immune checkpoint blockade and opportunities for combination therapies. Genes Dis 2019; 6:232-246. [PMID: 32042863 PMCID: PMC6997608 DOI: 10.1016/j.gendis.2019.06.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 06/07/2019] [Accepted: 06/16/2019] [Indexed: 12/30/2022] Open
Abstract
Immune checkpoint blockade therapies (ICBs) are a prominent breakthrough in cancer immunotherapy in recent years (named the 2013 “Breakthrough of the Year” by the Science magazine). Thus far, FDA-approved ICBs primarily target immune checkpoints CTLA-4, PD-1, and PD-L1. Notwithstanding their impressive long-term therapeutic benefits, their efficacy is limited to a small subset of cancer patients. In addition, ICBs induce inadvertent immune-related adverse events (irAEs) and can be costly for long-term use. To overcome these limitations, two strategies are actively being pursued: identification of predictive biomarkers for clinical response to ICBs and multi-pronged combination therapies. Biomarkers will allow clinicians to practice a precision medicine approach in ICBs (biomarker-based patient selection) such as treating triple-negative breast cancer patients that exhibit PD-L1 staining of tumor-infiltrating immune cells in ≥1% of the tumor area with nanoparticle albumin-bound (nab)–paclitaxel plus anti-PD-L1 and treating patients of MSI-H or MMR deficient unresectable or metastatic solid tumors with pembrolizumab (anti-PD-1). Importantly, the insights gained from these biomarker studies can guide rational combinatorial strategies such as CDK4/6 inhibitor/fractionated radiotherapy/HDACi in conjunction with ICBs to maximize therapeutic benefits. Further, with the rapid technological advents (e.g., ATCT-Seq), we predict more reliable biomarkers will be identified, which in turn will inspire more promising combination therapies.
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Affiliation(s)
- Hongxing Shen
- Department of Radiation Oncology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,O'Neal Comprehensive Cancer Center, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA
| | - Eddy Shih-Hsin Yang
- Department of Radiation Oncology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,O'Neal Comprehensive Cancer Center, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA
| | - Marty Conry
- O'Neal Comprehensive Cancer Center, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,Department of Medical Oncology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA
| | - John Fiveash
- Department of Radiation Oncology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,O'Neal Comprehensive Cancer Center, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA
| | - Carlo Contreras
- O'Neal Comprehensive Cancer Center, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,Department of Surgical Oncology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA
| | - James A Bonner
- Department of Radiation Oncology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,O'Neal Comprehensive Cancer Center, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA
| | - Lewis Zhichang Shi
- Department of Radiation Oncology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,O'Neal Comprehensive Cancer Center, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,Department of Microbiology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA.,Program in Immunology, The University of Alabama at Birmingham School of Medicine, Birmingham, AL, 35233, USA
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30
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Eckert F, Zwirner K, Boeke S, Thorwarth D, Zips D, Huber SM. Rationale for Combining Radiotherapy and Immune Checkpoint Inhibition for Patients With Hypoxic Tumors. Front Immunol 2019; 10:407. [PMID: 30930892 PMCID: PMC6423917 DOI: 10.3389/fimmu.2019.00407] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 02/15/2019] [Indexed: 12/19/2022] Open
Abstract
In order to compensate for the increased oxygen consumption in growing tumors, tumors need angiogenesis and vasculogenesis to increase the supply. Insufficiency in this process or in the microcirculation leads to hypoxic tumor areas with a significantly reduced pO2, which in turn leads to alterations in the biology of cancer cells as well as in the tumor microenvironment. Cancer cells develop more aggressive phenotypes, stem cell features and are more prone to metastasis formation and migration. In addition, intratumoral hypoxia confers therapy resistance, specifically radioresistance. Reactive oxygen species are crucial in fixing DNA breaks after ionizing radiation. Thus, hypoxic tumor cells show a two- to threefold increase in radioresistance. The microenvironment is enriched with chemokines (e.g., SDF-1) and growth factors (e.g., TGFβ) additionally reducing radiosensitivity. During recent years hypoxia has also been identified as a major factor for immune suppression in the tumor microenvironment. Hypoxic tumors show increased numbers of myeloid derived suppressor cells (MDSCs) as well as regulatory T cells (Tregs) and decreased infiltration and activation of cytotoxic T cells. The combination of radiotherapy with immune checkpoint inhibition is on the rise in the treatment of metastatic cancer patients, but is also tested in multiple curative treatment settings. There is a strong rationale for synergistic effects, such as increased T cell infiltration in irradiated tumors and mitigation of radiation-induced immunosuppressive mechanisms such as PD-L1 upregulation by immune checkpoint inhibition. Given the worse prognosis of patients with hypoxic tumors due to local therapy resistance but also increased rate of distant metastases and the strong immune suppression induced by hypoxia, we hypothesize that the subgroup of patients with hypoxic tumors might be of special interest for combining immune checkpoint inhibition with radiotherapy.
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Affiliation(s)
- Franziska Eckert
- Department of Radiation Oncology, University Hospital Tuebingen, Tuebingen, Germany
- German Cancer Consortium (DKTK) Partnersite Tuebingen, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Kerstin Zwirner
- Department of Radiation Oncology, University Hospital Tuebingen, Tuebingen, Germany
| | - Simon Boeke
- Department of Radiation Oncology, University Hospital Tuebingen, Tuebingen, Germany
- German Cancer Consortium (DKTK) Partnersite Tuebingen, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Section for Biomedical Physics, Department of Radiation Oncology, University Hospital Tuebingen, Tuebingen, Germany
| | - Daniela Thorwarth
- German Cancer Consortium (DKTK) Partnersite Tuebingen, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Section for Biomedical Physics, Department of Radiation Oncology, University Hospital Tuebingen, Tuebingen, Germany
| | - Daniel Zips
- Department of Radiation Oncology, University Hospital Tuebingen, Tuebingen, Germany
- German Cancer Consortium (DKTK) Partnersite Tuebingen, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Stephan M. Huber
- Department of Radiation Oncology, University Hospital Tuebingen, Tuebingen, Germany
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31
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Bachs O, Gallastegui E, Orlando S, Bigas A, Morante-Redolat JM, Serratosa J, Fariñas I, Aligué R, Pujol MJ. Role of p27 Kip1 as a transcriptional regulator. Oncotarget 2018; 9:26259-26278. [PMID: 29899857 PMCID: PMC5995243 DOI: 10.18632/oncotarget.25447] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 05/01/2018] [Indexed: 12/16/2022] Open
Abstract
The protein p27Kip1 is a member of the Cip/Kip family of cyclin-dependent kinase (Cdk) inhibitors. It interacts with both the catalytic and the regulatory subunit (cyclin) and introduces a region into the catalytic cleave of the Cdk inducing its inactivation. Its inhibitory capacity can be modulated by specific tyrosine phosphorylations. p27Kip1 also behaves as a transcriptional regulator. It associates with specific chromatin domains through different transcription factors. ChIP on chip, ChIP-seq and expression microarray analysis allowed the identification of the transcriptional programs regulated by p27Kip1. Thus, important cellular functions as cell division cycle, respiration, RNA processing, translation and cell adhesion, are under p27Kip1 regulation. Moreover, genes involved in pathologies as cancer and neurodegeneration are also regulated by p27Kip1, suggesting its implication in these pathologies. The carboxyl moiety of p27Kip1 can associate with different proteins, including transcriptional regulators. In contrast, its NH2-terminal region specifically interacts with cyclin-Cdk complexes. The general mechanistic model of how p27Kip1 regulates transcription is that it associates by its COOH region to the transcriptional regulators on the chromatin and by the NH2-domain to cyclin-Cdk complexes. After Cdk activation it would phosphorylate the specific targets on the chromatin leading to gene expression. This model has been demonstrated to apply in the transcriptional regulation of p130/E2F4 repressed genes involved in cell cycle progression. We summarize in this review our current knowledge on the role of p27Kip1 in the regulation of transcription, on the transcriptional programs under its regulation and on its relevance in pathologies as cancer and neurodegeneration.
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Affiliation(s)
- Oriol Bachs
- Department of Biomedical Sciences, Faculty of Medicine, University of Barcelona, IDIBAPS, CIBERONC, Barcelona, Spain
| | - Edurne Gallastegui
- Department of Biomedical Sciences, Faculty of Medicine, University of Barcelona, IDIBAPS, CIBERONC, Barcelona, Spain
| | - Serena Orlando
- Department of Biomedical Sciences, Faculty of Medicine, University of Barcelona, IDIBAPS, CIBERONC, Barcelona, Spain
| | - Anna Bigas
- Program in Cancer Research, Institut Hospital Del Mar d'Investigacions Mèdiques (IMIM), CIBERONC, Barcelona, Spain
| | - José Manuel Morante-Redolat
- Departamento de Biología Celular, Biología Funcional y Antropología Física and ERI de Biotecnología y Biomedicina, CIBERNED, Universidad de Valencia, Valencia, Spain
| | - Joan Serratosa
- Department of Cerebral Ischemia and Neurodegeneration, Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), IDIBAPS, Barcelona, Spain
| | - Isabel Fariñas
- Departamento de Biología Celular, Biología Funcional y Antropología Física and ERI de Biotecnología y Biomedicina, CIBERNED, Universidad de Valencia, Valencia, Spain
| | - Rosa Aligué
- Department of Biomedical Sciences, Faculty of Medicine, University of Barcelona, IDIBAPS, CIBERONC, Barcelona, Spain
| | - Maria Jesús Pujol
- Department of Biomedical Sciences, Faculty of Medicine, University of Barcelona, IDIBAPS, CIBERONC, Barcelona, Spain
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32
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Sulkowski PL, Scanlon SE, Oeck S, Glazer PM. PTEN Regulates Nonhomologous End Joining By Epigenetic Induction of NHEJ1/XLF. Mol Cancer Res 2018; 16:1241-1254. [PMID: 29739874 DOI: 10.1158/1541-7786.mcr-17-0581] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 03/23/2018] [Accepted: 04/23/2018] [Indexed: 11/16/2022]
Abstract
DNA double-strand breaks (DSB) are the most cytotoxic DNA lesions, and up to 90% of DSBs require repair by nonhomologous end joining (NHEJ). Functional and genomic analyses of patient-derived melanomas revealed that PTEN loss is associated with NHEJ deficiency. In PTEN-null melanomas, PTEN complementation rescued the NHEJ defect; conversely, suppression of PTEN compromised NHEJ. Mechanistic studies revealed that PTEN promotes NHEJ through direct induction of expression of XRCC4-like factor (NHEJ1/XLF), which functions in DNA end bridging and ligation. PTEN was found to occupy the NHEJ1 gene promoter and to recruit the histone acetyltransferases, PCAF and CBP, inducing XLF expression. This recruitment activity was found to be independent of its phosphatase activity, but dependent on K128, a site of regulatory acetylation on PTEN. These findings define a novel function for PTEN in regulating NHEJ DSB repair, and therefore may assist in the design of individualized strategies for cancer therapy.Implications: PTEN is the second most frequently lost tumor suppressor gene. Here it is demonstrated that PTEN has a direct and novel regulatory role in NHEJ, a key DNA repair pathway in response to radiation and chemotherapy. Mol Cancer Res; 16(8); 1241-54. ©2018 AACR.
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Affiliation(s)
| | - Susan E Scanlon
- Department of Experimental Pathology, Yale University, New Haven, Connecticut
| | - Sebastian Oeck
- Department of Therapeutic Radiology, Yale University, New Haven, Connecticut.,Institute of Cell Biology (Cancer Research), University of Duisburg-Essen, Essen, Germany
| | - Peter M Glazer
- Department of Genetics, Yale University, New Haven, Connecticut. .,Department of Therapeutic Radiology, Yale University, New Haven, Connecticut
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33
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Differentiated embryo chondrocyte plays a crucial role in DNA damage response via transcriptional regulation under hypoxic conditions. PLoS One 2018; 13:e0192136. [PMID: 29466367 PMCID: PMC5821451 DOI: 10.1371/journal.pone.0192136] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 01/17/2018] [Indexed: 12/21/2022] Open
Abstract
Tumor hypoxia contributes to a biologically aggressive phenotype and therapeutic resistance. Recent studies have revealed that hypoxia reduces expression of several DNA damage recognition and repair (DRR) genes via both hypoxia-inducible factor (HIF)-independent and -dependent pathways, and this induced genomic instability in cancer cells. We show here that one of the HIF-target genes—differentiated embryo chondrocyte (DEC)—plays a role in DNA damage response via transcriptional repression. Comprehensive gene expression and database analyses have revealed systemic repression of DNA-DRR genes in cancer and non-cancer cells under hypoxic conditions. Hypoxic repression in typical cases was confirmed by quantitative RT-PCR and promoter reporter experiments, and knockdown experiments indicated the critical role of DEC2 in such repression. Assessment of histone H2AX phosphorylation revealed that recognition and repair of DNA double-strand breaks (DSBs) induced by bleomycin or γ-ray irradiation were attenuated; moreover, Cleaved Caspase-3 levels were decreased with pre-conditioning under hypoxia: opposing phenomena were ascertained by knockdown of DEC2. Finally, pre-conditioning under hypoxia decreased the sensitivity of cancer cells to DSBs, and knockdown of DEC2 increased γ-ray sensitivity. These data imply that a critical reduction of DNA-DRR occurs via DEC-dependent transcriptional repression and suggest that DEC is a potential molecular target for anti-cancer strategies.
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34
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Scanlon SE, Hegan DC, Sulkowski PL, Glazer PM. Suppression of homology-dependent DNA double-strand break repair induces PARP inhibitor sensitivity in VHL-deficient human renal cell carcinoma. Oncotarget 2018; 9:4647-4660. [PMID: 29435132 PMCID: PMC5797003 DOI: 10.18632/oncotarget.23470] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 11/28/2017] [Indexed: 11/25/2022] Open
Abstract
The von Hippel-Lindau (VHL) tumor suppressor gene is inactivated in the vast majority of human clear cell renal carcinomas. The pathogenesis of VHL loss is currently best understood to occur through stabilization of the hypoxia-inducible factors, activation of hypoxia-induced signaling pathways, and transcriptional reprogramming towards a pro-angiogenic and pro-growth state. However, hypoxia also drives other pro-tumorigenic processes, including the development of genomic instability via down-regulation of DNA repair gene expression. Here, we find that DNA repair genes involved in double-strand break repair by homologous recombination (HR) and in mismatch repair, which are down-regulated by hypoxic stress, are decreased in VHL-deficient renal cancer cells relative to wild type VHL-complemented cells. Functionally, this gene repression is associated with impaired DNA double-strand break repair in VHL-deficient cells, as determined by the persistence of ionizing radiation-induced DNA double-strand breaks and reduced repair activity in a homology-dependent plasmid reactivation assay. Furthermore, VHL deficiency conferred increased sensitivity to PARP inhibitors, analogous to the synthetic lethality observed between hypoxia and these agents. Finally, we discovered a correlation between VHL inactivation and reduced HR gene expression in a large panel of human renal carcinoma samples. Together, our data elucidate a novel connection between VHL-deficient renal carcinoma and hypoxia-induced down-regulation of DNA repair, and identify potential opportunities for targeting DNA repair defects in human renal cell carcinoma.
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Affiliation(s)
- Susan E. Scanlon
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Experimental Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - Denise C. Hegan
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - Parker L. Sulkowski
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - Peter M. Glazer
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
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35
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Tiana M, Acosta-Iborra B, Puente-Santamaría L, Hernansanz-Agustin P, Worsley-Hunt R, Masson N, García-Rio F, Mole D, Ratcliffe P, Wasserman WW, Jimenez B, del Peso L. The SIN3A histone deacetylase complex is required for a complete transcriptional response to hypoxia. Nucleic Acids Res 2018; 46:120-133. [PMID: 29059365 PMCID: PMC5758878 DOI: 10.1093/nar/gkx951] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 10/02/2017] [Accepted: 10/06/2017] [Indexed: 01/02/2023] Open
Abstract
Cells adapt to environmental changes, including fluctuations in oxygen levels, through the induction of specific gene expression programs. To identify genes regulated by hypoxia at the transcriptional level, we pulse-labeled HUVEC cells with 4-thiouridine and sequenced nascent transcripts. Then, we searched genome-wide binding profiles from the ENCODE project for factors that correlated with changes in transcription and identified binding of several components of the Sin3A co-repressor complex, including SIN3A, SAP30 and HDAC1/2, proximal to genes repressed by hypoxia. SIN3A interference revealed that it participates in the downregulation of 75% of the hypoxia-repressed genes in endothelial cells. Unexpectedly, it also blunted the induction of 47% of the upregulated genes, suggesting a role for this corepressor in gene induction. In agreement, ChIP-seq experiments showed that SIN3A preferentially localizes to the promoter region of actively transcribed genes and that SIN3A signal was enriched in hypoxia-repressed genes, prior exposure to the stimulus. Importantly, SINA3 occupancy was not altered by hypoxia in spite of changes in H3K27ac signal. In summary, our results reveal a prominent role for SIN3A in the transcriptional response to hypoxia and suggest a model where modulation of the associated histone deacetylase activity, rather than its recruitment, determines the transcriptional output.
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Affiliation(s)
- Maria Tiana
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM) and Instituto de Investigaciones Biomédicas ‘Alberto Sols’ (CSIC-UAM), 28029 Madrid, Spain
- IdiPaz, Instituto de Investigación Sanitaria del Hospital Universitario La Paz, 28029 Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Barbara Acosta-Iborra
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM) and Instituto de Investigaciones Biomédicas ‘Alberto Sols’ (CSIC-UAM), 28029 Madrid, Spain
| | - Laura Puente-Santamaría
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM) and Instituto de Investigaciones Biomédicas ‘Alberto Sols’ (CSIC-UAM), 28029 Madrid, Spain
| | - Pablo Hernansanz-Agustin
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM) and Instituto de Investigaciones Biomédicas ‘Alberto Sols’ (CSIC-UAM), 28029 Madrid, Spain
- Servicio Inmunología, Hospital Universitario de La Princesa, Instituto de Investigación Sanitaria del hospital de La Princesa, 28006 Madrid, Spain
| | - Rebecca Worsley-Hunt
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia Vancouver, British Columbia V5Z 4H4, Canada
| | - Norma Masson
- Target Discovery Institute, University of Oxford, Oxford OX3 7FZ, UK
| | - Francisco García-Rio
- IdiPaz, Instituto de Investigación Sanitaria del Hospital Universitario La Paz, 28029 Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Servicio de Neumología, Hospital Universitario La Paz, Instituto de Investigación Sanitaria del hospital de La Paz, 28029 Madrid, Spain
| | - David Mole
- Henry Wellcome Building for Molecular Physiology, University of Oxford, Oxford OX3 7BN, UK
| | - Peter Ratcliffe
- Target Discovery Institute, University of Oxford, Oxford OX3 7FZ, UK
| | - Wyeth W Wasserman
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia Vancouver, British Columbia V5Z 4H4, Canada
| | - Benilde Jimenez
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM) and Instituto de Investigaciones Biomédicas ‘Alberto Sols’ (CSIC-UAM), 28029 Madrid, Spain
- IdiPaz, Instituto de Investigación Sanitaria del Hospital Universitario La Paz, 28029 Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Luis del Peso
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM) and Instituto de Investigaciones Biomédicas ‘Alberto Sols’ (CSIC-UAM), 28029 Madrid, Spain
- IdiPaz, Instituto de Investigación Sanitaria del Hospital Universitario La Paz, 28029 Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain
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Heumann A, Heinemann N, Hube-Magg C, Lang DS, Grupp K, Kluth M, Minner S, Möller-Koop C, Graefen M, Heinzer H, Tsourlakis MC, Wilczak W, Wittmer C, Jacobsen F, Huland H, Simon R, Schlomm T, Sauter G, Steurer S, Lebok P, Hinsch A. High BCAR1 expression is associated with early PSA recurrence in ERG negative prostate cancer. BMC Cancer 2018; 18:37. [PMID: 29304771 PMCID: PMC5756403 DOI: 10.1186/s12885-017-3956-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 12/21/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Breast cancer anti-estrogen resistance 1 (BCAR1/p130cas) is a hub for diverse oncogenic signaling cascades and promotes tumor development and progression. METHODS To understand the effect of BCAR1 in prostate cancer, we analyzed its expression on more than 11,000 prostate cancer samples. BCAR1 expression levels were compared with clinical characteristics, PSA recurrence, molecular subtype defined by ERG status and 3p, 5q, 6q and PTEN deletion. RESULTS BCAR1 staining was barely detectable in normal prostate glands but seen in 77.6% of 9472 interpretable cancers, including strong expression in 38.5%, moderate in 23.2% and weak in 15.9% of cases. BCAR1 up regulation was associated with positive ERG status (p < 0.0001), high Gleason score (p < 0.0001), advanced pathological tumor stage (p = 0.0082), lower preoperative PSA level (p < 0.0001), increased cell proliferation (p < 0.0001), early PSA recurrence (p = 0.0008), and predicted prognosis independently from clinico-pathological parameters available at the time of the initial biopsy. However, subset analyses revealed that the prognostic impact of BCAR1 expression was limited to ERG-negative cancer. That BCAR1 up regulation was linked to almost all analyzed deletions (p < 0.0001 each for PTEN, 5q, 6q deletion) may suggest a functional link to genomic instability. CONCLUSION The results of our study identify BCAR1 as a prognostic biomarker with potential clinical value for risk stratification of ERG-negative prostate cancer.
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Affiliation(s)
- Asmus Heumann
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Nina Heinemann
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Claudia Hube-Magg
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Dagmar S Lang
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Katharina Grupp
- General, Visceral and Thoracic Surgery Department and Clinic, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, Germany
| | - Martina Kluth
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Sarah Minner
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Christina Möller-Koop
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Markus Graefen
- Martini-Clinic, Prostate Cancer Center, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, Germany
| | - Hans Heinzer
- Martini-Clinic, Prostate Cancer Center, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, Germany
| | - Maria Christina Tsourlakis
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Waldemar Wilczak
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Corinna Wittmer
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Frank Jacobsen
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Hartwig Huland
- Martini-Clinic, Prostate Cancer Center, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, Germany
| | - Ronald Simon
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
| | - Thorsten Schlomm
- Martini-Clinic, Prostate Cancer Center, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, Germany.,Department of Urology, Section for translational Prostate Cancer Research, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, Germany
| | - Guido Sauter
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Stefan Steurer
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Patrick Lebok
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Andrea Hinsch
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
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Song L, McNeil EM, Ritchie AM, Astell KR, Gourley C, Melton DW. Melanoma cells replicate through chemotherapy by reducing levels of key homologous recombination protein RAD51 and increasing expression of translesion synthesis DNA polymerase ζ. BMC Cancer 2017; 17:864. [PMID: 29254481 PMCID: PMC5735618 DOI: 10.1186/s12885-017-3864-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 11/30/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The global incidence of melanoma has been increasing faster than any other form of cancer. New therapies offer exciting prospects for improved survival, but the development of resistance is a major problem and there remains a need for additional effective melanoma therapy. Platinum compounds, such as cisplatin, are the most effective chemotherapeutics for a number of major cancers, but are ineffective on metastatic melanoma. They cause monofunctional adducts and intrastrand crosslinks that are repaired by nucleotide excision repair, as well as the more toxic interstrand crosslinks that are repaired by a combination of nuclease activity and homologous recombination. METHODS We investigated the mechanism of melanoma resistance to cisplatin using a panel of melanoma and control cell lines. Cisplatin-induced changes in levels of the key homologous recombination protein RAD51 and compensatory changes in translesion synthesis DNA polymerases were identified by western blotting and qRT-PCR. Flow cytometry, immunofluorescence and western blotting were used to compare the cell cycle and DNA damage response and the induction of apoptosis in cisplatin-treated melanoma and control cells. Ectopic expression of a tagged form of RAD51 and siRNA knockdown of translesion synthesis DNA polymerase zeta were used to investigate the mechanism that allowed cisplatin-treated melanoma cells to continue to replicate. RESULTS We have identified and characterised a novel DNA damage response mechanism in melanoma. Instead of increasing levels of RAD51 on encountering cisplatin-induced interstrand crosslinks during replication, melanoma cells shut down RAD51 synthesis and instead boost levels of translesion synthesis DNA polymerase zeta to allow replication to proceed. This response also resulted in synthetic lethality to the PARP inhibitor olaparib. CONCLUSIONS This unusual DNA damage response may be a more appropriate strategy for an aggressive and rapidly growing tumour like melanoma that enables it to better survive chemotherapy, but also results in increased sensitivity of cultured melanoma cells to the PARP inhibitor olaparib.
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Affiliation(s)
- Liang Song
- Edinburgh Cancer Research Centre, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Ewan M McNeil
- Edinburgh Cancer Research Centre, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Ann-Marie Ritchie
- Edinburgh Cancer Research Centre, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Katy R Astell
- Edinburgh Cancer Research Centre, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU, UK.,Present Address: Centre for Neuroregeneration, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Charlie Gourley
- Edinburgh Cancer Research Centre, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU, UK
| | - David W Melton
- Edinburgh Cancer Research Centre, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU, UK.
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38
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Scanlon SE, Scanlon CD, Hegan DC, Sulkowski PL, Glazer PM. Nickel induces transcriptional down-regulation of DNA repair pathways in tumorigenic and non-tumorigenic lung cells. Carcinogenesis 2017; 38:627-637. [PMID: 28472268 DOI: 10.1093/carcin/bgx038] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 04/22/2017] [Indexed: 11/14/2022] Open
Abstract
The heavy metal nickel is a known carcinogen, and occupational exposure to nickel compounds has been implicated in human lung and nasal cancers. Unlike many other environmental carcinogens, however, nickel does not directly induce DNA mutagenesis, and the mechanism of nickel-related carcinogenesis remains incompletely understood. Cellular nickel exposure leads to signaling pathway activation, transcriptional changes and epigenetic remodeling, processes also impacted by hypoxia, which itself promotes tumor growth without causing direct DNA damage. One of the mechanisms by which hypoxia contributes to tumor growth is the generation of genomic instability via down-regulation of high-fidelity DNA repair pathways. Here, we find that nickel exposure similarly leads to down-regulation of DNA repair proteins involved in homology-dependent DNA double-strand break repair (HDR) and mismatch repair (MMR) in tumorigenic and non-tumorigenic human lung cells. Functionally, nickel induces a defect in HDR capacity, as determined by plasmid-based host cell reactivation assays, persistence of ionizing radiation-induced DNA double-strand breaks and cellular hypersensitivity to ionizing radiation. Mechanistically, we find that nickel, in contrast to the metalloid arsenic, acutely induces transcriptional repression of HDR and MMR genes as part of a global transcriptional pattern similar to that seen with hypoxia. Finally, we find that exposure to low-dose nickel reduces the activity of the MLH1 promoter, but only arsenic leads to long-term MLH1 promoter silencing. Together, our data elucidate novel mechanisms of heavy metal carcinogenesis and contribute to our understanding of the influence of the microenvironment on the regulation of DNA repair pathways.
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Affiliation(s)
- Susan E Scanlon
- Department of Therapeutic Radiology and.,Department of Experimental Pathology, Yale University School of Medicine, New Haven, CT 06520-8040, USA
| | - Christine D Scanlon
- Department of Therapeutic Radiology and.,Department of Chemistry, Miss Porter's School, Farmington, CT 06032, USA and
| | - Denise C Hegan
- Department of Therapeutic Radiology and.,Department of Genetics, Yale University School of Medicine, New Haven, CT 06520-8040, USA
| | - Parker L Sulkowski
- Department of Therapeutic Radiology and.,Department of Genetics, Yale University School of Medicine, New Haven, CT 06520-8040, USA
| | - Peter M Glazer
- Department of Therapeutic Radiology and.,Department of Genetics, Yale University School of Medicine, New Haven, CT 06520-8040, USA
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Riffle S, Hegde RS. Modeling tumor cell adaptations to hypoxia in multicellular tumor spheroids. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2017; 36:102. [PMID: 28774341 PMCID: PMC5543535 DOI: 10.1186/s13046-017-0570-9] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 07/18/2017] [Indexed: 12/17/2022]
Abstract
Under hypoxic conditions, tumor cells undergo a series of adaptations that promote evolution of a more aggressive tumor phenotype including the activation of DNA damage repair proteins, altered metabolism, and decreased proliferation. Together these changes mitigate the negative impact of oxygen deprivation and allow preservation of genomic integrity and proliferative capacity, thus contributing to tumor growth and metastasis. As a result the presence of a hypoxic microenvironment is considered a negative clinical feature of many solid tumors. Hypoxic niches in tumors also represent a therapeutically privileged environment in which chemo- and radiation therapy is less effective. Although the negative impact of tumor hypoxia has been well established, the precise effect of oxygen deprivation on tumor cell behavior, and the molecular signals that allow a tumor cell to survive in vivo are poorly understood. Multicellular tumor spheroids (MCTS) have been used as an in vitro model for the avascular tumor niche, capable of more accurately recreating tumor genomic profiles and predicting therapeutic response. However, relatively few studies have used MCTS to study the molecular mechanisms driving tumor cell adaptations within the hypoxic tumor environment. Here we will review what is known about cell proliferation, DNA damage repair, and metabolic pathways as modeled in MCTS in comparison to observations made in solid tumors. A more precise definition of the cell populations present within 3D tumor models in vitro could better inform our understanding of the heterogeneity within tumors as well as provide a more representative platform for the testing of therapeutic strategies.
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Affiliation(s)
- Stephen Riffle
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA
| | - Rashmi S Hegde
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA.
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40
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Fitzgerald DM, Hastings PJ, Rosenberg SM. Stress-Induced Mutagenesis: Implications in Cancer and Drug Resistance. ANNUAL REVIEW OF CANCER BIOLOGY 2017; 1:119-140. [PMID: 29399660 PMCID: PMC5794033 DOI: 10.1146/annurev-cancerbio-050216-121919] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Genomic instability underlies many cancers and generates genetic variation that drives cancer initiation, progression, and therapy resistance. In contrast with classical assumptions that mutations occur purely stochastically at constant, gradual rates, microbes, plants, flies, and human cancer cells possess mechanisms of mutagenesis that are upregulated by stress responses. These generate transient, genetic-diversity bursts that can propel evolution, specifically when cells are poorly adapted to their environments-that is, when stressed. We review molecular mechanisms of stress-response-dependent (stress-induced) mutagenesis that occur from bacteria to cancer, and are activated by starvation, drugs, hypoxia, and other stressors. We discuss mutagenic DNA break repair in Escherichia coli as a model for mechanisms in cancers. The temporal regulation of mutagenesis by stress responses and spatial restriction in genomes are common themes across the tree of life. Both can accelerate evolution, including the evolution of cancers. We discuss possible anti-evolvability drugs, aimed at targeting mutagenesis and other variation generators, that could be used to delay the evolution of cancer progression and therapy resistance.
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Affiliation(s)
- Devon M Fitzgerald
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston Texas 77030
- The Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030
| | - P J Hastings
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
- The Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030
| | - Susan M Rosenberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston Texas 77030
- The Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030
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41
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Wiedmeier JE, Ohlrich A, Chu A, Rountree MR, Turker MS. Induction of the long noncoding RNA NBR2 from the bidirectional BRCA1 promoter under hypoxic conditions. Mutat Res 2017; 796:13-19. [PMID: 28249151 DOI: 10.1016/j.mrfmmm.2017.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 01/27/2017] [Accepted: 02/09/2017] [Indexed: 06/06/2023]
Abstract
BRCA1 plays an important role in preventing breast cancer and is often silenced or repressed in sporadic cancer. The BRCA1 promoter is bidirectional: it drives transcription of the long non-coding (lnc) NBR2 transcript in the opposite orientation relative to the BRCA1 transcript. Hypoxic conditions repress BRCA1 transcription, but their effect on expression of the NBR2 transcript has not been reported. We used quantitative RT-PCR to measure BRCA1 and NBR2 transcript levels in 0% and 1% oxygen in MCF-7 breast cancer cells and found that NBR2 transcript levels increased as a function of time under hypoxic conditions, whereas BRCA1 mRNA levels were repressed. Hypoxic conditions were ineffective in reducing BRCA1 mRNA in the UACC-3199 breast cancer cell line, which is reported to have an epigenetically silenced BRCA1 promoter, even though appreciable levels of BRCA1 and NBR2 mRNA were detected. Significant recovery back to baseline RNA levels occurred within 48h after the MCF-7 cells were restored to normoxic conditions. We used a construct with the 218bp minimal BRCA1 promoter linked to marker genes to show that this minimal promoter repressed expression bidirectionally under hypoxic conditions, which suggests that the elements necessary for induction of NBR2 are located elsewhere.
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Affiliation(s)
- J Erin Wiedmeier
- University of Utah School of Medicine, Salt Lake City, UT 84132, United States
| | - Anna Ohlrich
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, 97239, United States
| | - Adrian Chu
- University of Utah School of Medicine, Salt Lake City, UT 84132, United States
| | | | - Mitchell S Turker
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, 97239, United States.
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Nabavi N, Bennewith KL, Churg A, Wang Y, Collins CC, Mutti L. Switching off malignant mesothelioma: exploiting the hypoxic microenvironment. Genes Cancer 2016; 7:340-354. [PMID: 28191281 PMCID: PMC5302036 DOI: 10.18632/genesandcancer.124] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 12/31/2016] [Indexed: 12/21/2022] Open
Abstract
Malignant mesotheliomas are aggressive, asbestos-related cancers with poor patient prognosis, typically arising in the mesothelial surfaces of tissues in pleural and peritoneal cavity. The relative unspecific symptoms of mesotheliomas, misdiagnoses, and lack of precise targeted therapies call for a more critical assessment of this disease. In the present review, we categorize commonly identified genomic aberrations of mesotheliomas into their canonical pathways and discuss targeting these pathways in the context of tumor hypoxia, a hallmark of cancer known to render solid tumors more resistant to radiation and most chemo-therapy. We then explore the concept that the intrinsic hypoxic microenvironment of mesotheliomas can be Achilles' heel for targeted, multimodal therapeutic intervention.
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Affiliation(s)
- Noushin Nabavi
- Laboratory for Advanced Genome Analysis, Vancouver Prostate Centre, BC, Canada
- Department of Urologic Sciences, University of British Columbia, BC, Canada
- Department of Experimental Therapeutics, BC Cancer Agency, BC, Canada
| | - Kevin L. Bennewith
- Department of Integrative Oncology, BC Cancer Agency, BC, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, BC, Canada
| | - Andrew Churg
- Department of Pathology and Laboratory Medicine, University of British Columbia, BC, Canada
| | - Yuzhuo Wang
- Department of Urologic Sciences, University of British Columbia, BC, Canada
- Department of Experimental Therapeutics, BC Cancer Agency, BC, Canada
| | - Colin C. Collins
- Laboratory for Advanced Genome Analysis, Vancouver Prostate Centre, BC, Canada
- Department of Urologic Sciences, University of British Columbia, BC, Canada
| | - Luciano Mutti
- Italian Group for Research and Therapy for Mesothelioma (GIMe) & School of Environment and Life Sciences, University of Salford, Manchester, United Kingdom
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Abstract
The E2F family of transcription factors is a key determinant of cell proliferation in response to extra- and intra-cellular signals. Within this family, E2F4 is a transcriptional repressor whose activity is critical to engage and maintain cell cycle arrest in G0/G1 in conjunction with members of the retinoblastoma (RB) family. However, recent observations challenge this paradigm and indicate that E2F4 has a multitude of functions in cells besides this cell cycle regulatory role, including in embryonic and adult stem cells, during regenerative processes, and in cancer. Some of these new functions are independent of the RB family and involve direct activation of target genes. Here we review the canonical functions of E2F4 and discuss recent evidence expanding the role of this transcription factor, with a focus on cell fate decisions in tissue homeostasis and regeneration.
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Affiliation(s)
- Jenny Hsu
- a Departments of Pediatrics and Genetics , Stanford University , Stanford , CA , USA
| | - Julien Sage
- a Departments of Pediatrics and Genetics , Stanford University , Stanford , CA , USA
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44
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Kaushik Tiwari M, Adaku N, Peart N, Rogers FA. Triplex structures induce DNA double strand breaks via replication fork collapse in NER deficient cells. Nucleic Acids Res 2016; 44:7742-54. [PMID: 27298253 PMCID: PMC5027492 DOI: 10.1093/nar/gkw515] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 05/31/2016] [Indexed: 12/20/2022] Open
Abstract
Structural alterations in DNA can serve as natural impediments to replication fork stability and progression, resulting in DNA damage and genomic instability. Naturally occurring polypurine mirror repeat sequences in the human genome can create endogenous triplex structures evoking a robust DNA damage response. Failures to recognize or adequately process these genomic lesions can result in loss of genomic integrity. Nucleotide excision repair (NER) proteins have been found to play a prominent role in the recognition and repair of triplex structures. We demonstrate using triplex-forming oligonucleotides that chromosomal triplexes perturb DNA replication fork progression, eventually resulting in fork collapse and the induction of double strand breaks (DSBs). We find that cells deficient in the NER damage recognition proteins, XPA and XPC, accumulate more DSBs in response to chromosomal triplex formation than NER-proficient cells. Furthermore, we demonstrate that XPC-deficient cells are particularly prone to replication-associated DSBs in the presence of triplexes. In the absence of XPA or XPC, deleterious consequences of triplex-induced genomic instability may be averted by activating apoptosis via dual phosphorylation of the H2AX protein. Our results reveal that damage recognition by XPC and XPA is critical to maintaining replication fork integrity and preventing replication fork collapse in the presence of triplex structures.
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Affiliation(s)
- Meetu Kaushik Tiwari
- Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Nneoma Adaku
- Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Natoya Peart
- Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Faye A Rogers
- Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06520, USA Yale Cancer Center, Yale School of Medicine, New Haven, CT 06520, USA
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45
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Hasvold G, Lund-Andersen C, Lando M, Patzke S, Hauge S, Suo Z, Lyng H, Syljuåsen RG. Hypoxia-induced alterations of G2 checkpoint regulators. Mol Oncol 2016; 10:764-73. [PMID: 26791779 DOI: 10.1016/j.molonc.2015.12.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 12/23/2015] [Accepted: 12/23/2015] [Indexed: 02/07/2023] Open
Abstract
Hypoxia promotes an aggressive tumor phenotype with increased genomic instability, partially due to downregulation of DNA repair pathways. However, genome stability is also surveilled by cell cycle checkpoints. An important issue is therefore whether hypoxia also can influence the DNA damage-induced cell cycle checkpoints. Here, we show that hypoxia (24 h 0.2% O2) alters the expression of several G2 checkpoint regulators, as examined by microarray gene expression analysis and immunoblotting of U2OS cells. While some of the changes reflected hypoxia-induced inhibition of cell cycle progression, the levels of several G2 checkpoint regulators, in particular Cyclin B, were reduced in G2 phase cells after hypoxic exposure, as shown by flow cytometric barcoding analysis of individual cells. These effects were accompanied by decreased phosphorylation of a Cyclin dependent kinase (CDK) target in G2 phase cells after hypoxia, suggesting decreased CDK activity. Furthermore, cells pre-exposed to hypoxia showed increased G2 checkpoint arrest upon treatment with ionizing radiation. Similar results were found following other hypoxic conditions (∼0.03% O2 20 h and 0.2% O2 72 h). These results demonstrate that the DNA damage-induced G2 checkpoint can be altered as a consequence of hypoxia, and we propose that such alterations may influence the genome stability of hypoxic tumors.
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Affiliation(s)
- Grete Hasvold
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0310 Oslo, Norway
| | - Christin Lund-Andersen
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0310 Oslo, Norway
| | - Malin Lando
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0310 Oslo, Norway
| | - Sebastian Patzke
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0310 Oslo, Norway
| | - Sissel Hauge
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0310 Oslo, Norway
| | - ZhenHe Suo
- Department of Pathology, Norwegian Radium Hospital, Oslo University Hospital, 0310 Oslo, Norway; Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Heidi Lyng
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0310 Oslo, Norway
| | - Randi G Syljuåsen
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0310 Oslo, Norway.
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46
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Homologous Recombination Repair Factors Rad51 and BRCA1 Are Necessary for Productive Replication of Human Papillomavirus 31. J Virol 2015; 90:2639-52. [PMID: 26699641 DOI: 10.1128/jvi.02495-15] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 12/16/2015] [Indexed: 02/06/2023] Open
Abstract
UNLABELLED High-risk human papillomavirus 31 (HPV31)-positive cells exhibit constitutive activation of the ATM-dependent DNA damage response (DDR), which is necessary for productive viral replication. In response to DNA double-strand breaks (DSBs), ATM activation leads to DNA repair through homologous recombination (HR), which requires the principal recombinase protein Rad51, as well as BRCA1. Previous studies from our lab demonstrated that Rad51 and BRCA1 are expressed at high levels in HPV31-positive cells and localize to sites of viral replication. These results suggest that HPV may utilize ATM activity to increase HR activity as a means to facilitate viral replication. In this study, we demonstrate that high-risk HPV E7 expression alone is sufficient for the increase in Rad51 and BRCA1 protein levels. We have found that this increase occurs, at least in part, at the level of transcription. Studies analyzing protein stability indicate that HPV may also protect Rad51 and BRCA1 from turnover, contributing to the overall increase in cellular levels. We also demonstrate that Rad51 is bound to HPV31 genomes, with binding increasing per viral genome upon productive replication. We have found that depletion of Rad51 and BRCA1, as well as inhibition of Rad51's recombinase activity, abrogates productive viral replication upon differentiation. Overall, these results indicate that Rad51 and BRCA1 are required for the process of HPV31 genome amplification and suggest that productive replication occurs in a manner dependent upon recombination. IMPORTANCE Productive replication of HPV31 requires activation of an ATM-dependent DNA damage response, though how ATM activity contributes to replication is unclear. Rad51 and BRCA1 play essential roles in repair of double-strand breaks, as well as the restart of stalled replication forks through homologous recombination (HR). Given that ATM activity is required to initiate HR repair, coupled with the requirement of Rad51 and BRCA1 for productive viral replication, our findings suggest that HPV may utilize ATM activity to ensure localization of recombination factors to productively replicating viral genomes. The finding that E7 increases the levels of Rad51 and BRCA1 suggests that E7 contributes to productive replication by providing DNA repair factors required for viral DNA synthesis. Our studies not only imply a role for recombination in the regulation of productive HPV replication but provide further insight into how HPV manipulates the DDR to facilitate the productive phase of the viral life cycle.
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Bigot N, Mouche A, Preti M, Loisel S, Renoud ML, Le Guével R, Sensebé L, Tarte K, Pedeux R. Hypoxia Differentially Modulates the Genomic Stability of Clinical-Grade ADSCs and BM-MSCs in Long-Term Culture. Stem Cells 2015; 33:3608-20. [PMID: 26422646 DOI: 10.1002/stem.2195] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 08/02/2015] [Indexed: 12/12/2022]
Abstract
Long-term cultures under hypoxic conditions have been demonstrated to maintain the phenotype of mesenchymal stromal/stem cells (MSCs) and to prevent the emergence of senescence. According to several studies, hypoxia has frequently been reported to drive genomic instability in cancer cells and in MSCs by hindering the DNA damage response and DNA repair. Thus, we evaluated the occurrence of DNA damage and repair events during the ex vivo expansion of clinical-grade adipose-derived stromal cells (ADSCs) and bone marrow (BM)-derived MSCs cultured with platelet lysate under 21% (normoxia) or 1% (hypoxia) O2 conditions. Hypoxia did not impair cell survival after DNA damage, regardless of MSC origin. However, ADSCs, unlike BM-MSCs, displayed altered γH2AX signaling and increased ubiquitylated γH2AX levels under hypoxic conditions, indicating an impaired resolution of DNA damage-induced foci. Moreover, hypoxia specifically promoted BM-MSC DNA integrity, with increased Ku80, TP53BP1, BRCA1, and RAD51 expression levels and more efficient nonhomologous end joining and homologous recombination repair. We further observed that hypoxia favored mtDNA stability and maintenance of differentiation potential after genotoxic stress. We conclude that long-term cultures under 1% O2 were more suitable for BM-MSCs as suggested by improved genomic stability compared with ADSCs.
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Affiliation(s)
- Nicolas Bigot
- INSERM U917, Microenvironnement et Cancer, Rennes, France.,Université de Rennes 1, Rennes, France.,Etablissement Français du Sang Bretagne, Rennes, France
| | - Audrey Mouche
- INSERM U917, Microenvironnement et Cancer, Rennes, France.,Université de Rennes 1, Rennes, France.,Etablissement Français du Sang Bretagne, Rennes, France
| | - Milena Preti
- Etablissement Français du Sang Pyrénées Méditerranée, Toulouse, France.,Université Paul Sabatier, Toulouse, France.,UMR5273-INSERM U1031, Toulouse, France
| | - Séverine Loisel
- INSERM U917, Microenvironnement et Cancer, Rennes, France.,Université de Rennes 1, Rennes, France.,Etablissement Français du Sang Bretagne, Rennes, France
| | - Marie-Laure Renoud
- Etablissement Français du Sang Pyrénées Méditerranée, Toulouse, France.,Université Paul Sabatier, Toulouse, France.,UMR5273-INSERM U1031, Toulouse, France
| | - Rémy Le Guével
- Université de Rennes 1, Rennes, France.,ImPACcell, SFR Biosit, Université de Rennes 1, Rennes, France
| | - Luc Sensebé
- Etablissement Français du Sang Pyrénées Méditerranée, Toulouse, France.,Université Paul Sabatier, Toulouse, France.,UMR5273-INSERM U1031, Toulouse, France
| | - Karin Tarte
- INSERM U917, Microenvironnement et Cancer, Rennes, France.,Université de Rennes 1, Rennes, France.,Etablissement Français du Sang Bretagne, Rennes, France.,Service ITeCH, CHU Pontchaillou, Rennes, France
| | - Rémy Pedeux
- INSERM U917, Microenvironnement et Cancer, Rennes, France.,Université de Rennes 1, Rennes, France.,Etablissement Français du Sang Bretagne, Rennes, France
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Wang Y, Deng O, Feng Z, Du Z, Xiong X, Lai J, Yang X, Xu M, Wang H, Taylor D, Yan C, Chen C, Difeo A, Ma Z, Zhang J. RNF126 promotes homologous recombination via regulation of E2F1-mediated BRCA1 expression. Oncogene 2015; 35:1363-72. [PMID: 26234677 PMCID: PMC4740281 DOI: 10.1038/onc.2015.198] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 04/08/2015] [Accepted: 05/10/2015] [Indexed: 01/13/2023]
Abstract
RNF126 is an E3 ubiquitin ligase. The deletion of RNF126 gene was observed in a wide range of human cancers and is correlated with improved disease-free and overall survival. These data highlights the clinical relevance of RNF126 in tumorigenesis and cancer therapy. However, the specific functions of RNF126 remain largely unknown. Homologous recombination (HR)-mediated DNA double-strand break repair is important for tumor suppression and cancer therapy resistance. Here, we demonstrate that RNF126 facilitates HR by promoting the expression of BRCA1, in a manner independent of its E3 ligase activity but depending on E2F1, a well-known transcription factor of BRCA1 promoter. In support of this result, RNF126 promotes transactivation of BRCA1 promoter by directly binding to E2F1. Most importantly, an RNF126 mutant lacking 11 amino acids that is responsible for the interaction with E2F1 has a dominant-negative effect on BRCA1 expression and HR by suppressing E2F1-mediated transactivation of BRCA1 promoter and blocking the enrichment of E2F1 on BRCA1 promoter. Lastly, RNF126 depletion leads to the increased sensitivity to ionizing radiation (IR) and poly (ADP-ribose) polymerase (PARP) inhibition. Collectively, our results suggest a novel role of RNF126 in promoting HR-mediated repair through positive regulation on BRCA1 expression by direct interaction with E2F1. This study not only offers novel insights into our current understanding of the biological functions of RNF126 but also provides a potential therapeutic target for cancer treatment.
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Affiliation(s)
- Y Wang
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - O Deng
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.,Department of Breast Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Z Feng
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Z Du
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - X Xiong
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - J Lai
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.,The Second Affiliated Hospital of Fujian Medical University, QuanZhou, Fujian, China
| | - X Yang
- Department of Breast Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - M Xu
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - H Wang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD, USA
| | - D Taylor
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - C Yan
- GRU Cancer Center, Georgia Regents University, Augusta, GA, USA
| | - C Chen
- Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - A Difeo
- General Medical Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - Z Ma
- Department of Breast Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - J Zhang
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
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49
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Gazy I, Zeevi DA, Renbaum P, Zeligson S, Eini L, Bashari D, Smith Y, Lahad A, Goldberg M, Ginsberg D, Levy-Lahad E. TODRA, a lncRNA at the RAD51 Locus, Is Oppositely Regulated to RAD51, and Enhances RAD51-Dependent DSB (Double Strand Break) Repair. PLoS One 2015; 10:e0134120. [PMID: 26230935 PMCID: PMC4521930 DOI: 10.1371/journal.pone.0134120] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 07/06/2015] [Indexed: 12/18/2022] Open
Abstract
Expression of RAD51, a crucial player in homologous recombination (HR) and DNA double-strand break (DSB) repair, is dysregulated in human tumors, and can contribute to genomic instability and tumor progression. To further understand RAD51 regulation we functionally characterized a long non-coding (lnc) RNA, dubbed TODRA (Transcribed in the Opposite Direction of RAD51), transcribed 69bp upstream to RAD51, in the opposite direction. We demonstrate that TODRA is an expressed transcript and that the RAD51 promoter region is bidirectional, supporting TODRA expression (7-fold higher than RAD51 in this assay, p = 0.003). TODRA overexpression in HeLa cells induced expression of TPIP, a member of the TPTE family which includes PTEN. Similar to PTEN, we found that TPIP co-activates E2F1 induction of RAD51. Analysis of E2F1's effect on the bidirectional promoter showed that E2F1 binding to the same site that promotes RAD51 expression, results in downregulation of TODRA. Moreover, TODRA overexpression induces HR in a RAD51-dependent DSB repair assay, and increases formation of DNA damage-induced RAD51-positive foci. Importantly, gene expression in breast tumors supports our finding that E2F1 oppositely regulates RAD51 and TODRA: increased RAD51 expression, which is associated with an aggressive tumor phenotype (e.g. negative correlation with positive ER (r = -0.22, p = 0.02) and positive PR status (r = -0.27, p<0.001); positive correlation with ki67 status (r = 0.36, p = 0.005) and HER2 amplification (r = 0.41, p = 0.001)), correlates as expected with lower TODRA and higher E2F1 expression. However, although E2F1 induction resulted in TPIP downregulation in cell lines, we find that TPIP expression in tumors is not reduced despite higher E2F1 expression, perhaps contributing to increased RAD51 expression. Our results identify TPIP as a novel E2F1 co-activator, suggest a similar role for other TPTEs, and indicate that the TODRA lncRNA affects RAD51 dysregulation and RAD51-dependent DSB repair in malignancy. Importantly, gene expression in breast tumors supports our finding that E2F1 oppositely regulates RAD51 and TODRA: increased RAD51 expression, which is associated with an aggressive tumor phenotype (e.g. negative correlation with positive ER (r = -0.22, p = 0.02) and positive PR status (r = -0.27, p<0.001); positive correlation with ki67 status (r = 0.36, p = 0.005) and HER2 amplification (r = 0.41, p = 0.001)), correlates as expected with lower TODRA and higher E2F1 expression. However, although E2F1 induction resulted in TPIP downregulation in cell lines, we find that TPIP expression in tumors is not reduced despite higher E2F1 expression, perhaps contributing to increased RAD51 expression. Our results identify TPIP as a novel E2F1 co-activator, suggest a similar role for other TPTEs, and indicate that the TODRA lncRNA affects RAD51 dysregulation and RAD51-dependent DSB repair in malignancy.
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Affiliation(s)
- Inbal Gazy
- Human Genetics, Hebrew University Medical School, Jerusalem, Israel
- Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - David A. Zeevi
- Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Paul Renbaum
- Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Sharon Zeligson
- Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Lital Eini
- Department of Genetics, Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Dana Bashari
- The Mina and Everard Goodman Faculty of Life Science, Bar Ilan University, Ramat Gan, Israel
| | - Yoav Smith
- Genomic Data Analysis Unit, Hebrew University Medical School, Jerusalem, Israel
| | - Amnon Lahad
- Department of Family Medicine, Hebrew University Medical School, Jerusalem, Israel
- Clalit Health Services, Jerusalem, Israel
| | - Michal Goldberg
- Department of Genetics, Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Doron Ginsberg
- The Mina and Everard Goodman Faculty of Life Science, Bar Ilan University, Ramat Gan, Israel
| | - Ephrat Levy-Lahad
- Human Genetics, Hebrew University Medical School, Jerusalem, Israel
- Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
- * E-mail:
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50
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Scanlon SE, Glazer PM. Multifaceted control of DNA repair pathways by the hypoxic tumor microenvironment. DNA Repair (Amst) 2015; 32:180-189. [PMID: 25956861 DOI: 10.1016/j.dnarep.2015.04.030] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hypoxia, as a pervasive feature in the microenvironment of solid tumors, plays a significant role in cancer progression, metastasis, and ultimately clinical outcome. One key cellular consequence of hypoxic stress is the regulation of DNA repair pathways, which contributes to the genomic instability and mutator phenotype observed in human cancers. Tumor hypoxia can vary in severity and duration, ranging from acute fluctuating hypoxia arising from temporary blockages in the immature microvasculature, to chronic moderate hypoxia due to sparse vasculature, to complete anoxia at distances more than 150 μM from the nearest blood vessel. Paralleling the intra-tumor heterogeneity of hypoxia, the effects of hypoxia on DNA repair occur through diverse mechanisms. Acutely, hypoxia activates DNA damage signaling pathways, primarily via post-translational modifications. On a longer timescale, hypoxia leads to transcriptional and/or translational downregulation of most DNA repair pathways including DNA double-strand break repair, mismatch repair, and nucleotide excision repair. Furthermore, extended hypoxia can lead to long-term persistent silencing of certain DNA repair genes, including BRCA1 and MLH1, revealing a mechanism by which tumor suppressor genes can be inactivated. The discoveries of the hypoxic modulation of DNA repair pathways have highlighted many potential ways to target susceptibilities of hypoxic cancer cells. In this review, we will discuss the multifaceted hypoxic control of DNA repair at the transcriptional, post-transcriptional, and epigenetic levels, and we will offer perspective on the future of its clinical implications.
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Affiliation(s)
- Susan E Scanlon
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, USA; Department of Experimental Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - Peter M Glazer
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, USA; Department of Genetics, Yale University School of Medicine, New Haven, CT, USA.
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