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Wu J, Song L, Lu M, Gao Q, Xu S, Zhou P, Ma T. The multifaceted functions of DNA-PKcs: implications for the therapy of human diseases. MedComm (Beijing) 2024; 5:e613. [PMID: 38898995 PMCID: PMC11185949 DOI: 10.1002/mco2.613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 06/21/2024] Open
Abstract
The DNA-dependent protein kinase (DNA-PK), catalytic subunit, also known as DNA-PKcs, is complexed with the heterodimer Ku70/Ku80 to form DNA-PK holoenzyme, which is well recognized as initiator in the nonhomologous end joining (NHEJ) repair after double strand break (DSB). During NHEJ, DNA-PKcs is essential for both DNA end processing and end joining. Besides its classical function in DSB repair, DNA-PKcs also shows multifaceted functions in various biological activities such as class switch recombination (CSR) and variable (V) diversity (D) joining (J) recombination in B/T lymphocytes development, innate immunity through cGAS-STING pathway, transcription, alternative splicing, and so on, which are dependent on its function in NHEJ or not. Moreover, DNA-PKcs deficiency has been proven to be related with human diseases such as neurological pathogenesis, cancer, immunological disorder, and so on through different mechanisms. Therefore, it is imperative to summarize the latest findings about DNA-PKcs and diseases for better targeting DNA-PKcs, which have shown efficacy in cancer treatment in preclinical models. Here, we discuss the multifaceted roles of DNA-PKcs in human diseases, meanwhile, we discuss the progresses of DNA-PKcs inhibitors and their potential in clinical trials. The most updated review about DNA-PKcs will hopefully provide insights and ideas to understand DNA-PKcs associated diseases.
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Affiliation(s)
- Jinghong Wu
- Cancer Research CenterBeijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijingChina
| | - Liwei Song
- Department of Thoracic SurgeryBeijing Chest HospitalCapital Medical University, Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijingChina
| | - Mingjun Lu
- Cancer Research CenterBeijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijingChina
| | - Qing Gao
- Cancer Research CenterBeijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijingChina
| | - Shaofa Xu
- Department of Thoracic SurgeryBeijing Chest HospitalCapital Medical University, Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijingChina
| | - Ping‐Kun Zhou
- Beijing Key Laboratory for RadiobiologyBeijing Institute of Radiation MedicineBeijingChina
| | - Teng Ma
- Cancer Research CenterBeijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijingChina
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Li P, Gai X, Li Q, Yang Q, Yu X. DNA-PK participates in pre-rRNA biogenesis independent of DNA double-strand break repair. Nucleic Acids Res 2024; 52:6360-6375. [PMID: 38682589 PMCID: PMC11194077 DOI: 10.1093/nar/gkae316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 04/06/2024] [Accepted: 04/16/2024] [Indexed: 05/01/2024] Open
Abstract
Although DNA-PK inhibitors (DNA-PK-i) have been applied in clinical trials for cancer treatment, the biomarkers and mechanism of action of DNA-PK-i in tumor cell suppression remain unclear. Here, we observed that a low dose of DNA-PK-i and PARP inhibitor (PARP-i) synthetically suppresses BRCA-deficient tumor cells without inducing DNA double-strand breaks (DSBs). Instead, we found that a fraction of DNA-PK localized inside of nucleoli, where we did not observe obvious DSBs. Moreover, the Ku proteins recognize pre-rRNA that facilitates DNA-PKcs autophosphorylation independent of DNA damage. Ribosomal proteins are also phosphorylated by DNA-PK, which regulates pre-rRNA biogenesis. In addition, DNA-PK-i acts together with PARP-i to suppress pre-rRNA biogenesis and tumor cell growth. Collectively, our studies reveal a DNA damage repair-independent role of DNA-PK-i in tumor suppression.
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Affiliation(s)
- Peng Li
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Xiaochen Gai
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Qilin Li
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Qianqian Yang
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Xiaochun Yu
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
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Zhang JN, Dong MM, Cao W, Chen HG, Gu HY, Feng YL, Zhang EF, He JS, Liu SC, Xie AY, Cai Z. Disruption of DNA-PKcs-mediated cGAS retention on damaged chromatin potentiates DNA damage-inducing agent-induced anti-multiple myeloma activity. Br J Cancer 2024:10.1038/s41416-024-02742-3. [PMID: 38877108 DOI: 10.1038/s41416-024-02742-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 05/21/2024] [Accepted: 05/28/2024] [Indexed: 06/16/2024] Open
Abstract
BACKGROUND Targeting DNA damage repair factors, such as DNA-dependent protein kinase catalytic subunit (DNA-PKcs), may offer an opportunity for effective treatment of multiple myeloma (MM). In combination with DNA damage-inducing agents, this strategy has been shown to improve chemotherapies partially via activation of cGAS-STING pathway by an elevated level of cytosolic DNA. However, as cGAS is primarily sequestered by chromatin in the nucleus, it remains unclear how cGAS is released from chromatin and translocated into the cytoplasm upon DNA damage, leading to cGAS-STING activation. METHODS We examined the role of DNA-PKcs inhibition on cGAS-STING-mediated MM chemosensitivity by performing mass spectrometry and mechanism study. RESULTS Here, we found DNA-PKcs inhibition potentiated DNA damage-inducing agent doxorubicin-induced anti-MM effect by activating cGAS-STING signaling. The cGAS-STING activation in MM cells caused cell death partly via IRF3-NOXA-BAK axis and induced M1 polarization of macrophages. Moreover, this activation was not caused by defective classical non-homologous end joining (c-NHEJ). Instead, upon DNA damage induced by doxorubicin, inhibition of DNA-PKcs promoted cGAS release from cytoplasmic chromatin fragments and increased the amount of cytosolic cGAS and DNA, activating cGAS-STING. CONCLUSIONS Inhibition of DNA-PKcs could improve the efficacy of doxorubicin in treatment of MM by de-sequestrating cGAS in damaged chromatin.
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Affiliation(s)
- Jin-Na Zhang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Institute of Translational Medicine, Zhejiang University School of Medicine and Zhejiang University Cancer Center, Hangzhou, Zhejiang, China
| | - Meng-Meng Dong
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Institute of Translational Medicine, Zhejiang University School of Medicine and Zhejiang University Cancer Center, Hangzhou, Zhejiang, China
| | - Wen Cao
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Hao-Guang Chen
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Hui-Yao Gu
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yi-Li Feng
- Institute of Translational Medicine, Zhejiang University School of Medicine and Zhejiang University Cancer Center, Hangzhou, Zhejiang, China
- Key Laboratory of Laparoscopic Technology of Zhejiang Province, Department of General Surgery, Sir Run-Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Hangzhou Qiantang Hospital, Hangzhou, Zhejiang, China
| | - En-Fan Zhang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jing-Song He
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Si-Cheng Liu
- Institute of Translational Medicine, Zhejiang University School of Medicine and Zhejiang University Cancer Center, Hangzhou, Zhejiang, China
- Key Laboratory of Laparoscopic Technology of Zhejiang Province, Department of General Surgery, Sir Run-Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Hangzhou Qiantang Hospital, Hangzhou, Zhejiang, China
| | - An-Yong Xie
- Institute of Translational Medicine, Zhejiang University School of Medicine and Zhejiang University Cancer Center, Hangzhou, Zhejiang, China.
- Key Laboratory of Laparoscopic Technology of Zhejiang Province, Department of General Surgery, Sir Run-Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
- Hangzhou Qiantang Hospital, Hangzhou, Zhejiang, China.
| | - Zhen Cai
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
- Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, China.
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Ma S, Hao R, Lu YW, Wang HP, Hu J, Qi YX. Identification and Validation of Novel Metastasis-Related Immune Gene Signature in Breast Cancer. BREAST CANCER (DOVE MEDICAL PRESS) 2024; 16:199-219. [PMID: 38634039 PMCID: PMC11021863 DOI: 10.2147/bctt.s448642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 03/31/2024] [Indexed: 04/19/2024]
Abstract
Background Distant metastasis remains the leading cause of death among patients with breast cancer (BRCA). The process of cancer metastasis involves multiple mechanisms, including compromised immune system. However, not all genes involved in immune function have been comprehensively identified. Methods Firstly 1623 BRCA samples, including transcriptome sequencing and clinical information, were acquired from Gene Expression Omnibus (GSE102818, GSE45255, GSE86166) and The Cancer Genome Atlas-BRCA (TCGA-BRCA) dataset. Subsequently, weighted gene co-expression network analysis (WGCNA) was performed using the GSE102818 dataset to identify the most relevant module to the metastasis of BRCA. Besides, ConsensusClusterPlus was applied to divide TCGA-BRCA patients into two subgroups (G1 and G2). In the meantime, the least absolute shrinkage and selection operator (LASSO) regression analysis was used to construct a metastasis-related immune genes (MRIGs)_score to predict the metastasis and progression of cancer. Importantly, the expression of vital genes was validated through reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). Results The expression pattern of 76 MRIGs screened by WGCNA divided TCGA-BRCA patients into two subgroups (G1 and G2), and the prognosis of G1 group was worse. Also, G1 exhibited a higher mRNA expression level based on stemness index score and Tumor Immune Dysfunction and Exclusion score. In addition, higher MRIGs_score represented the higher probability of progression in BRCA patients. It was worth mentioning that the patients in the G1 group had a high MRIGs_score than those in the G2 group. Importantly, the results of RT-qPCR and IHC demonstrated that fasciculation and elongation protein zeta 1 (FEZ1) and insulin-like growth factor 2 receptor (IGF2R) were risk factors, while interleukin (IL)-1 receptor antagonist (IL1RN) was a protective factor. Conclusion Our study revealed a prognostic model composed of eight immune related genes that could predict the metastasis and progression of BRCA. Higher score represented higher metastasis probability. Besides, the consistency of key genes in BRCA tissue and bioinformatics analysis results from mRNA and protein levels was verified.
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Affiliation(s)
- Shen Ma
- Department of Breast Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050035, People’s Republic of China
| | - Ran Hao
- Institutes of Health Research, Hebei Medical University, Shijiazhuang, Hebei, 050017, People’s Republic of China
| | - Yi-Wei Lu
- Department of Breast Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050035, People’s Republic of China
| | - Hui-Po Wang
- Department of Breast Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050035, People’s Republic of China
| | - Jie Hu
- Institutes of Health Research, Hebei Medical University, Shijiazhuang, Hebei, 050017, People’s Republic of China
- Department of Science and Technology, Hebei Medical University, Shijiazhuang, Hebei, 050017, People’s Republic of China
| | - Yi-Xin Qi
- Department of Breast Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050035, People’s Republic of China
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Katoueezadeh M, Maleki P, Torabizadeh SA, Farsinejad A, Khalilabadi RM, Valandani HM, Nurain IO, Ashoub MH, Fatemi A. Combinatorial targeting of telomerase and DNA-PK induces synergistic apoptotic effects against Pre-B acute lymphoblastic leukemia cells. Mol Biol Rep 2024; 51:163. [PMID: 38252348 DOI: 10.1007/s11033-023-09087-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 11/30/2023] [Indexed: 01/23/2024]
Abstract
BACKGROUND Due to the high demand for novel approaches for leukemia-targeted therapy, this study investigates the impact of DNA-PK inhibitor NU7441 on the sensitivity of pre-B ALL cells to the telomerase inhibitor MST-312. METHODS The study involved NALM-6 cells treated with MST-312 and NU7441, assessing their viability and metabolic activity using trypan blue and MTT assays. The study also evaluated apoptosis, gene expression changes, and DNA damage using flow cytometry, qRT-PCR, and micronucleus assays. The binding energy of MST-312 in the active site of telomerase was calculated using molecular docking. RESULTS The study's findings revealed a synergistic decline in both cell viability and metabolic activity in NALM-6 cells when exposed to the combined treatment of MST-312 and NU7441, and this decrease occurred without any adverse effects on healthy PBMC cells. Furthermore, the combination treatment exhibited a significantly higher induction of apoptosis than treatment with MST-312 alone, as observed through flow cytometry assay. qRT-PCR analysis revealed that this enhanced apoptosis was associated with a notable downregulation of Bcl-2 expression and an upregulation of Bax gene expression. Moreover, the combination therapy decreased expression levels of hTERT and c-Myc genes. The micronucleus assay indicated that the combination treatment increased DNA damage in NALM-6 cells. Also, a good conformation between MST-312 and the active site of telomerase was revealed by docking data. CONCLUSIONS The study suggests that simultaneous inhibition of telomerase and DNA-PK in pre-B ALL presents a novel targeted therapy approach.
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Affiliation(s)
- Maryam Katoueezadeh
- Student Research Committee, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
- Department of Hematology and Medical Laboratory Sciences, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Parisa Maleki
- Student Research Committee, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
- Department of Hematology and Medical Laboratory Sciences, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Seyedeh Atekeh Torabizadeh
- Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Alireza Farsinejad
- Department of Hematology and Medical Laboratory Sciences, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
- Cell Therapy and Regenerative Medicine Comprehensive Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Roohollah Mirzaee Khalilabadi
- Department of Hematology and Medical Laboratory Sciences, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Hajar Mardani Valandani
- Department of Hematology and Medical Laboratory Sciences, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Ismaila Olanrewaju Nurain
- Postdoctoral Research Fellow, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON, Canada
| | - Muhammad Hossein Ashoub
- Department of Hematology and Medical Laboratory Sciences, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
- Cell Therapy and Regenerative Medicine Comprehensive Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Ahmad Fatemi
- Cellular and Molecular Research Center, Gerash University of Medical Sciences, Gerash, Iran.
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Lal S, Bhola NE, Sun BC, Chen Y, Huang T, Morton V, Chen KX, Xia S, Zhang H, Parikh NS, Ye Q, Veiby OP, Bellovin DI, Ji Y. Discovery and Characterization of ZL-2201, a Potent, Highly Selective, and Orally Bioavailable Small-molecule DNA-PK Inhibitor. CANCER RESEARCH COMMUNICATIONS 2023; 3:1731-1742. [PMID: 37663435 PMCID: PMC10473160 DOI: 10.1158/2767-9764.crc-23-0304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 09/05/2023]
Abstract
DNA-dependent protein kinase (DNA-PK), a driver of the non-homologous end-joining (NHEJ) DNA damage response pathway, plays an instrumental role in repairing double-strand breaks (DSB) induced by DNA-damaging poisons. We evaluate ZL-2201, an orally bioavailable, highly potent, and selective pharmacologic inhibitor of DNA-PK activity, for the treatment of human cancerous malignancies. ZL-2201 demonstrated greater selectivity for DNA-PK and effectively inhibited DNA-PK autophosphorylation in a concentration- and time-dependent manner. Initial data suggested a potential correlation between ataxia-telangiectasia mutated (ATM) deficiency and ZL-2201 sensitivity. More so, ZL-2201 showed strong synergy with topoisomerase II inhibitors independent of ATM status in vitro. In vivo oral administration of ZL-2201 demonstrated dose-dependent antitumor activity in the NCI-H1703 xenograft model and significantly enhanced the activity of approved DNA-damaging agents in A549 and FaDu models. From a phosphoproteomic mass spectrometry screen, we identified and validated that ZL-2201 and PRKDC siRNA decreased Ser108 phosphorylation of MCM2, a key DNA replication factor. Collectively, we have characterized a potent and selective DNA-PK inhibitor with promising monotherapy and combinatory therapeutic potential with approved DNA-damaging agents. More importantly, we identified phospho-MCM2 (Ser108) as a potential proximal biomarker of DNA-PK inhibition that warrants further preclinical and clinical evaluation. Significance ZL-2201, a potent and selective DNA-PK inhibitor, can target tumor models in combination with DNA DSB-inducing agents such as radiation or doxorubicin, with potential to improve recurrent therapies in the clinic.
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Affiliation(s)
- Shruti Lal
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | - Neil E. Bhola
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | - Bee-Chun Sun
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | - Yuping Chen
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | - Tom Huang
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | - Vivian Morton
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | | | | | | | - Nehal S. Parikh
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | - Qiuping Ye
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | - O. Petter Veiby
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
| | | | - Yuhua Ji
- Biologics Discovery, Zai Lab (US) LLC, Menlo Park, California
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Dexheimer TS, Coussens NP, Silvers T, Wright J, Morris J, Doroshow JH, Teicher BA. Multicellular Complex Tumor Spheroid Response to DNA Repair Inhibitors in Combination with DNA-damaging Drugs. CANCER RESEARCH COMMUNICATIONS 2023; 3:1648-1661. [PMID: 37637936 PMCID: PMC10452929 DOI: 10.1158/2767-9764.crc-23-0193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/20/2023] [Accepted: 07/25/2023] [Indexed: 08/29/2023]
Abstract
Multicellular spheroids comprised of malignant cells, endothelial cells, and mesenchymal stem cells served as an in vitro model of human solid tumors to investigate the potentiation of DNA-damaging drugs by pharmacologic modulation of DNA repair pathways. The DNA-damaging drugs, topotecan, trabectedin, and temozolomide were combined with varied inhibitors of DNA damage response enzymes including PARP (olaparib or talazoparib), ATM (ataxia telangiectasia mutated; AZD-1390), ATR (ataxia telangiectasia and Rad3-related protein; berzosertib or elimusertib), and DNA-PK (DNA-dependent protein kinase; nedisertib or VX-984). A range of clinically achievable concentrations were tested up to the clinical Cmax, if known. Mechanistically, the types of DNA damage induced by temozolomide, topotecan, and trabectedin are distinct, which was apparent from the response of spheroids to combinations with various DNA repair inhibitors. Although most combinations resulted in additive cytotoxicity, synergistic activity was observed for temozolomide combined with PARP inhibitors as well as combinations of the ATM inhibitor AZD-1390 with either topotecan or trabectedin. These findings might provide guidance for the selection of anticancer agent combinations worthy of further investigation. Significance Clinical efficacy of DNA-damaging anticancer drugs can be influenced by the DNA damage response in tumor cells. The potentiation of DNA-damaging drugs by pharmacologic modulation of DNA repair pathways was assessed in multicellular tumor spheroids. Although most combinations demonstrated additive cytotoxicity, synergistic cytotoxicity was observed for several drug combinations.
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Affiliation(s)
- Thomas S Dexheimer
- Molecular Pharmacology Laboratories, Applied and Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Nathan P Coussens
- Molecular Pharmacology Laboratories, Applied and Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Thomas Silvers
- Molecular Pharmacology Laboratories, Applied and Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - John Wright
- Division of Cancer Treatment and Diagnosis, NCI, Rockville, Maryland
| | - Joel Morris
- Division of Cancer Treatment and Diagnosis, NCI, Rockville, Maryland
| | - James H Doroshow
- Division of Cancer Treatment and Diagnosis, NCI, Rockville, Maryland
| | - Beverly A Teicher
- Division of Cancer Treatment and Diagnosis, NCI, Rockville, Maryland
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Kim DM, Lee SY, Lim JC, Cho EH, Park UJ. RUNX3 regulates the susceptibility against EGFR-targeted non-small cell lung cancer therapy using 47Sc-conjugated cetuximab. BMC Cancer 2023; 23:652. [PMID: 37438719 DOI: 10.1186/s12885-023-11161-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 07/07/2023] [Indexed: 07/14/2023] Open
Abstract
BACKGROUND Radioimmunotherapy with cetuximab and conjugates with various radioisotopes is a feasible treatment option for different tumor models. Scandium-47 (47Sc), one of several β--particle-emitting radioisotopes, displays favorable physical and chemical properties for conjugation to monoclonal antibodies. However, the therapeutic efficacy of 47Sc in preclinical and clinical studies is largely unknown. Given that intrinsic alterations in tumors greatly contribute to resistance to anti-epidermal growth factor receptor (EGFR)-targeted therapy, research on overcoming resistance to radioimmunotherapy using cetuximab is required. METHODS 47Sc was produced by irradiation of a CaCO3 target at the HANARO research reactor in KAERI (Korea Atomic Energy Research Institute) and prepared by chromatographic separation of the irradiated target. Cetuximab was conjugated with 47Sc using the bifunctional chelating agent DTPA. Radiochemical purity was determined using instant thin-layer chromatography. The immunoreactivity of 47Sc-DTPA-cetuximab was evaluated using the Lindmo method and an in vitro cell-binding assay. The inhibitory effects of cetuximab and 47Sc-DTPA-cetuximab were confirmed using cell growth inhibition and BrdU cell proliferation assays. Differences in protein expression levels between cetuximab- and 47Sc-DTPA-cetuximab-treated cells were confirmed using western blotting. Complex formation between RUNX3 and DNA repair components was confirmed using immunoprecipitation and western blotting. RESULTS Cetuximab induces cell cycle arrest and cell death in EGFR-overexpressing NSCLC cells. Radiolabeling of cetuximab with 47Sc led to increased therapeutic efficacy relative to cetuximab alone. Application of 47Sc-DTPA-cetuximab induced DNA damage responses, and activation of RUNX3 significantly enhanced the therapeutic efficacy of 47Sc-DTPA-cetuximab. RUNX3 mediated susceptibility to EGFR-targeted NSCLC therapy using 47Sc-DTPA-cetuximab via interaction with components of the DNA damage and repair machinery. CONCLUSIONS 47Sc-DTPA-cetuximab promoted cell death in EGFR-overexpressing NSCLC cells by targeting EGFR and inducing DNA damage as a result of β irradiation emitted from the conjugated 47Sc. Activation of RUNX3 played a key role in DNA damage and repair processes in response to the ionizing radiation and inhibited cell growth, thus leading to more effective tumor suppression. RUNX3 can potentially moderate susceptibility to 47Sc-conjugated cetuximab by modulating DNA damage and repair process mechanisms.
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Affiliation(s)
- Da-Mi Kim
- Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon, 34057, Republic of Korea.
| | - So-Young Lee
- Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon, 34057, Republic of Korea
| | - Jae-Cheong Lim
- Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon, 34057, Republic of Korea
| | - Eun-Ha Cho
- Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon, 34057, Republic of Korea
| | - Ul-Jae Park
- Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon, 34057, Republic of Korea
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Ando K, Suenaga Y, Kamijo T. DNA Ligase 4 Contributes to Cell Proliferation against DNA-PK Inhibition in MYCN-Amplified Neuroblastoma IMR32 Cells. Int J Mol Sci 2023; 24:ijms24109012. [PMID: 37240360 DOI: 10.3390/ijms24109012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/12/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Identifying the vulnerability of altered DNA repair machinery that displays synthetic lethality with MYCN amplification is a therapeutic rationale in unfavourable neuroblastoma. However, none of the inhibitors for DNA repair proteins are established as standard therapy in neuroblastoma. Here, we investigated whether DNA-PK inhibitor (DNA-PKi) could inhibit the proliferation of spheroids derived from neuroblastomas of MYCN transgenic mice and MYCN-amplified neuroblastoma cell lines. DNA-PKi exhibited an inhibitory effect on the proliferation of MYCN-driven neuroblastoma spheroids, whereas variable sensitivity was observed in those cell lines. Among them, the accelerated proliferation of IMR32 cells was dependent on DNA ligase 4 (LIG4), which comprises the canonical non-homologous end-joining pathway of DNA repair. Notably, LIG4 was identified as one of the worst prognostic factors in patients with MYCN-amplified neuroblastomas. It may play complementary roles in DNA-PK deficiency, suggesting the therapeutic potential of LIG4 inhibition in combination with DNA-PKi for MYCN-amplified neuroblastomas to overcome resistance to multimodal therapy.
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Affiliation(s)
- Kiyohiro Ando
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama 362-0806, Japan
| | - Yusuke Suenaga
- Chiba Cancer Center Research Institute, Chiba 260-8717, Japan
| | - Takehiko Kamijo
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama 362-0806, Japan
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DNA Damage and Its Role in Cancer Therapeutics. Int J Mol Sci 2023; 24:ijms24054741. [PMID: 36902170 PMCID: PMC10003233 DOI: 10.3390/ijms24054741] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 03/05/2023] Open
Abstract
DNA damage is a double-edged sword in cancer cells. On the one hand, DNA damage exacerbates gene mutation frequency and cancer risk. Mutations in key DNA repair genes, such as breast cancer 1 (BRCA1) and/or breast cancer 2 (BRCA2), induce genomic instability and promote tumorigenesis. On the other hand, the induction of DNA damage using chemical reagents or radiation kills cancer cells effectively. Cancer-burdening mutations in key DNA repair-related genes imply relatively high sensitivity to chemotherapy or radiotherapy because of reduced DNA repair efficiency. Therefore, designing specific inhibitors targeting key enzymes in the DNA repair pathway is an effective way to induce synthetic lethality with chemotherapy or radiotherapy in cancer therapeutics. This study reviews the general pathways involved in DNA repair in cancer cells and the potential proteins that could be targeted for cancer therapeutics.
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11
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Ovejero-Sánchez M, González-Sarmiento R, Herrero AB. DNA Damage Response Alterations in Ovarian Cancer: From Molecular Mechanisms to Therapeutic Opportunities. Cancers (Basel) 2023; 15:448. [PMID: 36672401 PMCID: PMC9856346 DOI: 10.3390/cancers15020448] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 01/12/2023] Open
Abstract
The DNA damage response (DDR), a set of signaling pathways for DNA damage detection and repair, maintains genomic stability when cells are exposed to endogenous or exogenous DNA-damaging agents. Alterations in these pathways are strongly associated with cancer development, including ovarian cancer (OC), the most lethal gynecologic malignancy. In OC, failures in the DDR have been related not only to the onset but also to progression and chemoresistance. It is known that approximately half of the most frequent subtype, high-grade serous carcinoma (HGSC), exhibit defects in DNA double-strand break (DSB) repair by homologous recombination (HR), and current evidence indicates that probably all HGSCs harbor a defect in at least one DDR pathway. These defects are not restricted to HGSCs; mutations in ARID1A, which are present in 30% of endometrioid OCs and 50% of clear cell (CC) carcinomas, have also been found to confer deficiencies in DNA repair. Moreover, DDR alterations have been described in a variable percentage of the different OC subtypes. Here, we overview the main DNA repair pathways involved in the maintenance of genome stability and their deregulation in OC. We also recapitulate the preclinical and clinical data supporting the potential of targeting the DDR to fight the disease.
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Affiliation(s)
- María Ovejero-Sánchez
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain
- Molecular Medicine Unit, Department of Medicine, University of Salamanca, 37007 Salamanca, Spain
- Institute of Molecular and Cellular Biology of Cancer (IBMCC), University of Salamanca-Spanish National Research Council, 37007 Salamanca, Spain
| | - Rogelio González-Sarmiento
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain
- Molecular Medicine Unit, Department of Medicine, University of Salamanca, 37007 Salamanca, Spain
- Institute of Molecular and Cellular Biology of Cancer (IBMCC), University of Salamanca-Spanish National Research Council, 37007 Salamanca, Spain
| | - Ana Belén Herrero
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain
- Molecular Medicine Unit, Department of Medicine, University of Salamanca, 37007 Salamanca, Spain
- Institute of Molecular and Cellular Biology of Cancer (IBMCC), University of Salamanca-Spanish National Research Council, 37007 Salamanca, Spain
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12
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Castellano GM, Zeeshan S, Garbuzenko OB, Sabaawy HE, Malhotra J, Minko T, Pine SR. Inhibition of Mtorc1/2 and DNA-PK via CC-115 Synergizes with Carboplatin and Paclitaxel in Lung Squamous Cell Carcinoma. Mol Cancer Ther 2022; 21:1381-1392. [PMID: 35732569 PMCID: PMC9452486 DOI: 10.1158/1535-7163.mct-22-0053] [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: 01/19/2022] [Revised: 03/30/2022] [Accepted: 06/14/2022] [Indexed: 11/16/2022]
Abstract
Only a small percentage (<1%) of patients with late-stage lung squamous cell carcinoma (LUSC) are eligible for targeted therapy. Because PI3K/AKT/mTOR signaling, particularly Phosphatidylinositol 3-kinase CA (PIK3CA), is dysregulated in two-thirds of LUSC, and DNA damage response pathways are enriched in LUSC, we tested whether CC-115, a dual mTORC1/2 and DNA-PK inhibitor, sensitizes LUSC to chemotherapy. We demonstrate that CC-115 synergizes with carboplatin in six of 14 NSCLC cell lines, primarily PIK3CA-mutant LUSC. Synergy was more common in cell lines that had decreased basal levels of activated AKT and DNA-PK, evidenced by reduced P-S473-AKT, P-Th308-AKT, and P-S2056-DNA-PKcs. CC-115 sensitized LUSC to carboplatin by inhibiting chemotherapy-induced AKT activation and maintaining apoptosis, particularly in PIK3CA-mutant cells lacking wild-type (WT) TP53. In addition, pathway analysis revealed that enrichments in the IFNα and IFNγ pathways were significantly associated with synergy. In multiple LUSC patient-derived xenograft and cell line tumor models, CC-115 plus platinum-based doublet chemotherapy significantly inhibited tumor growth and increased overall survival as compared with either treatment alone at clinically relevant dosing schedules. IHC and immunoblot analysis of CC-115-treated tumors demonstrated decreased P-Th308-AKT, P-S473-AKT, P-S235/236-S6, and P-S2056-DNA-PKcs, showing direct pharmacodynamic evidence of inhibited PI3K/AKT/mTOR signaling cascades. Because PI3K pathway and DNA-PK inhibitors have shown toxicity in clinical trials, we assessed toxicity by examining weight and numerous organs in PRKDC-WT mice, which demonstrated that the combination treatment does not exacerbate the clinically accepted side effects of standard-of-care chemotherapy. This preclinical study provides strong support for the further investigation of CC-115 plus chemotherapy in LUSC.
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Affiliation(s)
- Gina M. Castellano
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Rutgers Graduate Program in Cellular and Molecular Pharmacology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
| | - Saman Zeeshan
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Rutgers Graduate Program in Cellular and Molecular Pharmacology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
| | - Olga B. Garbuzenko
- Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey
| | - Hatim E. Sabaawy
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Department of Medicine, Division of Medical Oncology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, New Brunswick, New Jersey
| | - Jyoti Malhotra
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Department of Medicine, Division of Medical Oncology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
| | - Tamara Minko
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey
| | - Sharon R. Pine
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Rutgers Graduate Program in Cellular and Molecular Pharmacology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Department of Medicine, Division of Medical Oncology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
- Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, New Jersey
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13
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Song L, Yu M, Jin R, Gu M, Wang Z, Hou D, Xu S, Wang J, Ma T. Long-Read Sequencing Annotation of the Transcriptome in DNA-PK Inactivated Cells. Front Oncol 2022; 12:941638. [PMID: 35992789 PMCID: PMC9382581 DOI: 10.3389/fonc.2022.941638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 06/23/2022] [Indexed: 12/22/2022] Open
Abstract
The DNA-dependent protein kinase catalytic subunit (DNA-PKcs) with a Ku70/Ku80 heterodimer constitutes the intact DNA-PK kinase, which is an upstream component of the DNA repair machinery that signals the DNA damage, orchestrates the DNA repair, and serves to maintain genome integrity. Beyond its role in DNA damage repair, the DNA-PK kinase is also implicated in transcriptional regulation and RNA metabolism, with an illuminated impact on tumor progression and therapeutic responses. However, the efforts to identify DNA-PK regulated transcriptomes are limited by short-read sequencing to resolve the full complexity of the transcriptome. Therefore, we leveraged the PacBio Single Molecule, Real-Time (SMRT) Sequencing platform to study the transcriptome after DNA-PK inactivation to further underscore the importance of its role in diseases. Our analysis revealed additional novel transcriptome and complex gene structures in the DNA-PK inactivated cells, identifying 8,355 high-confidence new isoforms from 3,197 annotated genes and 523 novel genes. Among them, 380 lncRNAs were identified. We validated these findings using computational approaches and confirmatory transcript quantification with short-read sequencing. Several novel isoforms representing distinct splicing events have been validated through PCR experiments. Our analyses provide novel insights into DNA-PK function in transcriptome regulation and RNA metabolism.
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Affiliation(s)
- Liwei Song
- Cancer Research Center, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
- Department of Thoracic Surgery, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Mengjun Yu
- Cancer Research Center, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Renjing Jin
- Cancer Research Center, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Meng Gu
- Cancer Research Center, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Ziyu Wang
- Cancer Research Center, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Dailun Hou
- Department of Radiology, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Shaofa Xu
- Department of Thoracic Surgery, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
- *Correspondence: Shaofa Xu, ; Jinghui Wang, ; Teng Ma,
| | - Jinghui Wang
- Cancer Research Center, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
- Department of Medical Oncology, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
- *Correspondence: Shaofa Xu, ; Jinghui Wang, ; Teng Ma,
| | - Teng Ma
- Cancer Research Center, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
- *Correspondence: Shaofa Xu, ; Jinghui Wang, ; Teng Ma,
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Chloroquine-Induced DNA Damage Synergizes with Nonhomologous End Joining Inhibition to Cause Ovarian Cancer Cell Cytotoxicity. Int J Mol Sci 2022; 23:ijms23147518. [PMID: 35886866 PMCID: PMC9323666 DOI: 10.3390/ijms23147518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/30/2022] [Accepted: 07/05/2022] [Indexed: 12/04/2022] Open
Abstract
Ovarian cancer (OC) is the most lethal gynecological malignancy; therefore, more effective treatments are urgently needed. We recently reported that chloroquine (CQ) increased reactive oxygen species (ROS) in OC cell lines (OCCLs), causing DNA double-strand breaks (DSBs). Here, we analyzed whether these lesions are repaired by nonhomologous end joining (NHEJ), one of the main pathways involved in DSB repair, and if the combination of CQ with NHEJ inhibitors (NHEJi) could be effective against OC. We found that NHEJ inhibition increased the persistence of γH2AX foci after CQ-induced DNA damage, revealing an essential role of this pathway in the repair of the lesions. NHEJi decreased the proliferation of OCCLs and a strong in vitro synergistic effect on apoptosis induction was observed when combined with CQ. This effect was largely abolished by the antioxidant N-Acetyl-L-cysteine, revealing the critical role of ROS and DSB generation in CQ/NHEJi-induced lethality. We also found that the NHEJ efficiency in OCCLs was not affected by treatment with Panobinostat, a pan-histone deacetylase inhibitor that also synergizes with CQ in OCCLs by impairing homologous recombination. Accordingly, the triple combination of CQ-NHEJi-Panobinostat exerted a stronger in vitro synergistic effect. Altogether, our data suggest that the combination of these drugs could represent new therapeutic strategies against OC.
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15
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Oxidative Stress and Deregulated DNA Damage Response Network in Lung Cancer Patients. Biomedicines 2022; 10:biomedicines10061248. [PMID: 35740268 PMCID: PMC9219789 DOI: 10.3390/biomedicines10061248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 02/04/2023] Open
Abstract
The deregulated DNA damage response (DDR) network is associated with the onset and progression of cancer. Herein, we searched for DDR defects in peripheral blood mononuclear cells (PBMCs) from lung cancer patients, and we evaluated factors leading to the augmented formation of DNA damage and/or its delayed/decreased removal. In PBMCs from 20 lung cancer patients at diagnosis and 20 healthy controls (HC), we analyzed oxidative stress and DDR-related parameters, including critical DNA repair mechanisms and apoptosis rates. Cancer patients showed higher levels of endogenous DNA damage than HC (p < 0.001), indicating accumulation of DNA damage in the absence of known exogenous genotoxic insults. Higher levels of oxidative stress and apurinic/apyrimidinic sites were observed in patients rather than HC (all p < 0.001), suggesting that increased endogenous DNA damage may emerge, at least in part, from these intracellular factors. Lower nucleotide excision repair and double-strand break repair capacities were found in patients rather than HC (all p < 0.001), suggesting that the accumulation of DNA damage can also be mediated by defective DNA repair mechanisms. Interestingly, reduced apoptosis rates were obtained in cancer patients compared with HC (p < 0.001). Consequently, the expression of critical DDR-associated genes was found deregulated in cancer patients. Together, oxidative stress and DDR-related aberrations contribute to the accumulation of endogenous DNA damage in PBMCs from lung cancer patients and can potentially be exploited as novel therapeutic targets and non-invasive biomarkers.
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Sheng D, Zhao B, Zhu W, Wang T, Peng Y. Scutellaria barbata D.Don (SBD) extracts suppressed tumor growth, metastasis and angiogenesis in Prostate cancer via PI3K/Akt pathway. BMC Complement Med Ther 2022; 22:120. [PMID: 35505400 PMCID: PMC9066752 DOI: 10.1186/s12906-022-03587-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 04/08/2022] [Indexed: 11/17/2022] Open
Abstract
Background Scutellaria barbata D.Don (SBD) is derived from the dried whole plant of Labiate which has been widely used to treat patients with multiple cancer. It was previously reported that the ethanol extract of SBD is able to promote apoptosis, and inhibit cell proliferation and angiogenesis in cancer. Materials and methods CCK8, Edu assays and colony formation assay were performed to assess the effect of SBD on PCa cell growth. Effect of SBD on apoptosis and cell cycle was detected by flow cytometry. Transwell and wounding healing assay were conducted to detect the invasion and migration activities of PCa cells. Western blot was employed to detect the protein expression. 2RRV1 mouse xenograft model was established to detect the effect of SBD on prostate cancer. Angiogenesis was analysed by coculturing PCa cell lines and HUVECs. Results The results showed that SBD induced a significant decrease in cell viability and clonogenic growth in a dose-dependent manner. SBD induced cell apoptosis and cell cycle G2/M phase arrest by inactivating PI3K/AKT signalling pathway. Treatment with SBD also significantly decreased the cell migration and invasion via phenotypic inversion of EMT that was characterized by the increased expression of E-cadherin and Vimentin, and decreased expression of N-cadherin, which could be partially attributed to inhibiting PI3K/AKT signalling pathway. Subsequently, using AKT inhibitor MK2206, we concluded that PI3K/AKT are also involved in cell apoptosis and metastasis of PCa cells stimulated by SBD. Apart from its direct effects on PCa cells, SBD also exhibited anti-angiogenic properties. SBD alone or conditioned media from SBD-treated PCa cells reduced HUVEC tube formation on Matrigel without affecting HUVEC viability. Furthermore, 22RV1 xenograft C57BL/6 mice treated with SBD in vivo showed a significant inhibitory in tumour size and tumour weight without toxicity. In addition, administration with medium- or high-dose of SBD significantly inhibited the cell proliferation and enhanced the damage to tumour tissues. Conclusions Collectively, our in vitro and in vivo findings suggest that SBD has the potential to develop into a safe and potent alternative therapy for PCa patients. Supplementary Information The online version contains supplementary material available at 10.1186/s12906-022-03587-0.
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Affiliation(s)
- Dongya Sheng
- Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Bei Zhao
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Wenjing Zhu
- Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Tiantian Wang
- Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yu Peng
- Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
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17
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DNA Damage Response Inhibitors in Cholangiocarcinoma: Current Progress and Perspectives. Cells 2022; 11:cells11091463. [PMID: 35563769 PMCID: PMC9101358 DOI: 10.3390/cells11091463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 04/16/2022] [Accepted: 04/24/2022] [Indexed: 12/27/2022] Open
Abstract
Cholangiocarcinoma (CCA) is a poorly treatable type of cancer and its incidence is dramatically increasing. The lack of understanding of the biology of this tumor has slowed down the identification of novel targets and the development of effective treatments. Based on next generation sequencing profiling, alterations in DNA damage response (DDR)-related genes are paving the way for DDR-targeting strategies in CCA. Based on the notion of synthetic lethality, several DDR-inhibitors (DDRi) have been developed with the aim of accumulating enough DNA damage to induce cell death in tumor cells. Observing that DDRi alone could be insufficient for clinical use in CCA patients, the combination of DNA-damaging regimens with targeted approaches has started to be considered, as evidenced by many emerging clinical trials. Hence, novel therapeutic strategies combining DDRi with patient-specific targeted drugs could be the next level for treating cholangiocarcinoma.
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Perspective on the Use of DNA Repair Inhibitors as a Tool for Imaging and Radionuclide Therapy of Glioblastoma. Cancers (Basel) 2022; 14:cancers14071821. [PMID: 35406593 PMCID: PMC8997380 DOI: 10.3390/cancers14071821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/24/2022] [Accepted: 03/29/2022] [Indexed: 01/03/2023] Open
Abstract
Simple Summary The current routine treatment for glioblastoma (GB), the most lethal high-grade brain tumor in adults, aims to induce DNA damage in the tumor. However, the tumor cells might be able to repair that damage, which leads to therapy resistance. Fortunately, DNA repair defects are common in GB cells, and their survival is often based on a sole backup repair pathway. Hence, targeted drugs inhibiting essential proteins of the DNA damage response have gained momentum and are being introduced in the clinic. This review gives a perspective on the use of radiopharmaceuticals targeting DDR kinases for imaging in order to determine the DNA repair phenotype of GB, as well as for effective radionuclide therapy. Finally, four new promising radiopharmaceuticals are suggested with the potential to lead to a more personalized GB therapy. Abstract Despite numerous innovative treatment strategies, the treatment of glioblastoma (GB) remains challenging. With the current state-of-the-art therapy, most GB patients succumb after about a year. In the evolution of personalized medicine, targeted radionuclide therapy (TRT) is gaining momentum, for example, to stratify patients based on specific biomarkers. One of these biomarkers is deficiencies in DNA damage repair (DDR), which give rise to genomic instability and cancer initiation. However, these deficiencies also provide targets to specifically kill cancer cells following the synthetic lethality principle. This led to the increased interest in targeted drugs that inhibit essential DDR kinases (DDRi), of which multiple are undergoing clinical validation. In this review, the current status of DDRi for the treatment of GB is given for selected targets: ATM/ATR, CHK1/2, DNA-PK, and PARP. Furthermore, this review provides a perspective on the use of radiopharmaceuticals targeting these DDR kinases to (1) evaluate the DNA repair phenotype of GB before treatment decisions are made and (2) induce DNA damage via TRT. Finally, by applying in-house selection criteria and analyzing the structural characteristics of the DDRi, four drugs with the potential to become new therapeutic GB radiopharmaceuticals are suggested.
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Dylgjeri E, Kothari V, Shafi AA, Semenova G, Gallagher PT, Guan YF, Pang A, Goodwin JF, Irani S, McCann JJ, Mandigo AC, Chand S, McNair CM, Vasilevskaya I, Schiewer MJ, Lallas CD, McCue PA, Gomella LG, Seifert EL, Carroll JS, Butler LM, Holst J, Kelly WK, Knudsen KE. A Novel Role for DNA-PK in Metabolism by Regulating Glycolysis in Castration-Resistant Prostate Cancer. Clin Cancer Res 2022; 28:1446-1459. [PMID: 35078861 PMCID: PMC9365345 DOI: 10.1158/1078-0432.ccr-21-1846] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 10/22/2021] [Accepted: 01/20/2022] [Indexed: 01/07/2023]
Abstract
PURPOSE DNA-dependent protein kinase catalytic subunit (DNA-PKcs, herein referred as DNA-PK) is a multifunctional kinase of high cancer relevance. DNA-PK is deregulated in multiple tumor types, including prostate cancer, and is associated with poor outcomes. DNA-PK was previously nominated as a therapeutic target and DNA-PK inhibitors are currently undergoing clinical investigation. Although DNA-PK is well studied in DNA repair and transcriptional regulation, much remains to be understood about the way by which DNA-PK drives aggressive disease phenotypes. EXPERIMENTAL DESIGN Here, unbiased proteomic and metabolomic approaches in clinically relevant tumor models uncovered a novel role of DNA-PK in metabolic regulation of cancer progression. DNA-PK regulation of metabolism was interrogated using pharmacologic and genetic perturbation using in vitro cell models, in vivo xenografts, and ex vivo in patient-derived explants (PDE). RESULTS Key findings reveal: (i) the first-in-field DNA-PK protein interactome; (ii) numerous DNA-PK novel partners involved in glycolysis; (iii) DNA-PK interacts with, phosphorylates (in vitro), and increases the enzymatic activity of glycolytic enzymes ALDOA and PKM2; (iv) DNA-PK drives synthesis of glucose-derived pyruvate and lactate; (v) DNA-PK regulates glycolysis in vitro, in vivo, and ex vivo; and (vi) combination of DNA-PK inhibitor with glycolytic inhibitor 2-deoxyglucose leads to additive anti-proliferative effects in aggressive disease. CONCLUSIONS Findings herein unveil novel DNA-PK partners, substrates, and function in prostate cancer. DNA-PK impacts glycolysis through direct interaction with glycolytic enzymes and modulation of enzymatic activity. These events support energy production that may contribute to generation and/or maintenance of DNA-PK-mediated aggressive disease phenotypes.
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Affiliation(s)
- Emanuela Dylgjeri
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Vishal Kothari
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Ayesha A. Shafi
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Galina Semenova
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Peter T. Gallagher
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Yi F. Guan
- School of Medical Sciences and Prince of Wales Clinical School, UNSW Sydney, Sydney, Australia
| | - Angel Pang
- School of Medical Sciences and Prince of Wales Clinical School, UNSW Sydney, Sydney, Australia
| | - Jonathan F. Goodwin
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Swati Irani
- South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
- Adelaide Medical School and Freemasons Foundation Centre for Male Health and Wellbeing, University of Adelaide, Adelaide, South Australia
| | - Jennifer J. McCann
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Amy C. Mandigo
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Saswati Chand
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Christopher M. McNair
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
- Sidney Kimmel Cancer Center at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Irina Vasilevskaya
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
- Sidney Kimmel Cancer Center at Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Matthew J. Schiewer
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
- Sidney Kimmel Cancer Center at Thomas Jefferson University, Philadelphia, Pennsylvania
- Department of Urology, Medical Oncology and Radiation Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Costas D. Lallas
- Department of Urology, Medical Oncology and Radiation Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Peter A. McCue
- Department of Urology, Medical Oncology and Radiation Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Leonard G. Gomella
- Department of Urology, Medical Oncology and Radiation Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Erin L. Seifert
- Department of Pathology, Anatomy and Cell Biology and MitoCare Center, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Jason S. Carroll
- Cancer Research UK Cambridge Research Institute, England, United Kingdom
| | - Lisa M. Butler
- South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
- Adelaide Medical School and Freemasons Foundation Centre for Male Health and Wellbeing, University of Adelaide, Adelaide, South Australia
| | - Jeff Holst
- School of Medical Sciences and Prince of Wales Clinical School, UNSW Sydney, Sydney, Australia
| | - William K. Kelly
- Sidney Kimmel Cancer Center at Thomas Jefferson University, Philadelphia, Pennsylvania
- Department of Urology, Medical Oncology and Radiation Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Karen E. Knudsen
- Department of Cancer Biology at Thomas Jefferson University, Philadelphia, Pennsylvania
- Sidney Kimmel Cancer Center at Thomas Jefferson University, Philadelphia, Pennsylvania
- Department of Urology, Medical Oncology and Radiation Oncology, Thomas Jefferson University, Philadelphia, Pennsylvania
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Wu WY, Wang ZX, Li TS, Ding XQ, Liu ZH, Yang J, Fang L, Kong LD. SSBP1 drives high fructose-induced glomerular podocyte ferroptosis via activating DNA-PK/p53 pathway. Redox Biol 2022; 52:102303. [PMID: 35390676 PMCID: PMC8990215 DOI: 10.1016/j.redox.2022.102303] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/13/2022] [Accepted: 03/23/2022] [Indexed: 01/14/2023] Open
Abstract
High fructose consumption is a significant risking factor for glomerular podocyte injury. However, the causes of high fructose-induced glomerular podocyte injury are still unclear. In this study, we reported a novel mechanism by which high fructose induced ferroptosis, a newly form of programmed cell death, in glomerular podocyte injury. We performed quantitative proteomic analysis in glomeruli of high fructose-fed rats to identify key regulating proteins involved in glomerular injury, and found that mitochondrial single-strand DNA-binding protein 1 (SSBP1) was markedly upregulated. Depletion of SSBP1 could alleviate high fructose-induced ferroptotic cell death in podocytes. Subsequently, we found that SSBP1 positively regulated a transcription factor p53 by interacting with DNA-dependent protein kinase (DNA-PK) and p53 to drive ferroptosis in high fructose-induced podocyte injury. Mechanically, SSBP1 activated DNA-PK to induce p53 phosphorylation at serine 15 (S15) to promote the nuclear accumulation of p53, and thereby inhibited expression of ferroptosis regulator solute carrier family 7 member 11 (SLC7A11) in high fructose-exposed podocytes. Natural antioxidant pterostilebene was showed to downregulate SSBP1 and then inhibit DNA-PK/p53 pathway in its alleviation of high fructose-induced glomerular podocyte ferroptosis and injury. This study identified SSBP1 as a novel intervention target against high fructose-induced podocyte ferroptosis and suggested that the suppression of SSBP1 by pterostilbene may be a potential therapy for the treatment of podocyte ferroptosis in glomerular injury.
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Affiliation(s)
- Wen-Yuan Wu
- State Key Laboratory of Pharmaceutical Biotechnology, Institute of Chinese Medicine, Nanjing Drum Tower Hospital, School of Life Sciences, Nanjing University, Nanjing, PR China
| | - Zi-Xuan Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Institute of Chinese Medicine, Nanjing Drum Tower Hospital, School of Life Sciences, Nanjing University, Nanjing, PR China
| | - Tu-Shuai Li
- State Key Laboratory of Pharmaceutical Biotechnology, Institute of Chinese Medicine, Nanjing Drum Tower Hospital, School of Life Sciences, Nanjing University, Nanjing, PR China
| | - Xiao-Qin Ding
- State Key Laboratory of Pharmaceutical Biotechnology, Institute of Chinese Medicine, Nanjing Drum Tower Hospital, School of Life Sciences, Nanjing University, Nanjing, PR China
| | - Zhi-Hong Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Institute of Chinese Medicine, Nanjing Drum Tower Hospital, School of Life Sciences, Nanjing University, Nanjing, PR China
| | - Jie Yang
- State Key Laboratory of Pharmaceutical Biotechnology, Institute of Chinese Medicine, Nanjing Drum Tower Hospital, School of Life Sciences, Nanjing University, Nanjing, PR China
| | - Lei Fang
- Jiangsu Key Laboratory of Molecular Medicine & Chemistry and Biomedicine Innovation Center, Medical School, Nanjing University, Nanjing, PR China.
| | - Ling-Dong Kong
- State Key Laboratory of Pharmaceutical Biotechnology, Institute of Chinese Medicine, Nanjing Drum Tower Hospital, School of Life Sciences, Nanjing University, Nanjing, PR China.
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21
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Targeting Protein Kinases and Epigenetic Control as Combinatorial Therapy Options for Advanced Prostate Cancer Treatment. Pharmaceutics 2022; 14:pharmaceutics14030515. [PMID: 35335890 PMCID: PMC8949110 DOI: 10.3390/pharmaceutics14030515] [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: 01/09/2022] [Revised: 02/15/2022] [Accepted: 02/21/2022] [Indexed: 02/02/2023] Open
Abstract
Prostate cancer (PC), the fifth leading cause of cancer-related mortality worldwide, is known as metastatic bone cancer when it spreads to the bone. Although there is still no effective treatment for advanced/metastatic PC, awareness of the molecular events that contribute to PC progression has opened up opportunities and raised hopes for the development of new treatment strategies. Androgen deprivation and androgen-receptor-targeting therapies are two gold standard treatments for metastatic PC. However, acquired resistance to these treatments is a crucial challenge. Due to the role of protein kinases (PKs) in the growth, proliferation, and metastases of prostatic tumors, combinatorial therapy by PK inhibitors may help pave the way for metastatic PC treatment. Additionally, PC is known to have epigenetic involvement. Thus, understanding epigenetic pathways can help adopt another combinatorial treatment strategy. In this study, we reviewed the PKs that promote PC to advanced stages. We also summarized some PK inhibitors that may be used to treat advanced PC and we discussed the importance of epigenetic control in this cancer. We hope the information presented in this article will contribute to finding an effective treatment for the management of advanced PC.
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22
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Choi W, Lee ES. Therapeutic Targeting of DNA Damage Response in Cancer. Int J Mol Sci 2022; 23:ijms23031701. [PMID: 35163621 PMCID: PMC8836062 DOI: 10.3390/ijms23031701] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 01/25/2022] [Accepted: 01/29/2022] [Indexed: 02/07/2023] Open
Abstract
DNA damage response (DDR) is critical to ensure genome stability, and defects in this signaling pathway are highly associated with carcinogenesis and tumor progression. Nevertheless, this also provides therapeutic opportunities, as cells with defective DDR signaling are directed to rely on compensatory survival pathways, and these vulnerabilities have been exploited for anticancer treatments. Following the impressive success of PARP inhibitors in the treatment of BRCA-mutated breast and ovarian cancers, extensive research has been conducted toward the development of pharmacologic inhibitors of the key components of the DDR signaling pathway. In this review, we discuss the key elements of the DDR pathway and how these molecular components may serve as anticancer treatment targets. We also summarize the recent promising developments in the field of DDR pathway inhibitors, focusing on novel agents beyond PARP inhibitors. Furthermore, we discuss biomarker studies to identify target patients expected to derive maximal clinical benefits as well as combination strategies with other classes of anticancer agents to synergize and optimize the clinical benefits.
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Affiliation(s)
- Wonyoung Choi
- Research Institute, National Cancer Center, Goyang 10408, Korea;
- Center for Clinical Trials, National Cancer Center, Goyang 10408, Korea
| | - Eun Sook Lee
- Research Institute, National Cancer Center, Goyang 10408, Korea;
- Center for Breast Cancer, National Cancer Center, Goyang 10408, Korea
- Correspondence: ; Tel.: +82-31-920-1633
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23
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Alemi F, Raei Sadigh A, Malakoti F, Elhaei Y, Ghaffari SH, Maleki M, Asemi Z, Yousefi B, Targhazeh N, Majidinia M. Molecular mechanisms involved in DNA repair in human cancers: An overview of PI3k/Akt signaling and PIKKs crosstalk. J Cell Physiol 2021; 237:313-328. [PMID: 34515349 DOI: 10.1002/jcp.30573] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/17/2021] [Accepted: 08/20/2021] [Indexed: 12/14/2022]
Abstract
The cellular genome is frequently subjected to abundant endogenous and exogenous factors that induce DNA damage. Most of the Phosphatidylinositol 3-kinase-related kinases (PIKKs) family members are activated in response to DNA damage and are the most important DNA damage response (DDR) proteins. The DDR system protects the cells against the wrecking effects of these genotoxicants and repairs the DNA damage caused by them. If the DNA damage is severe, such as when DNA is the goal of chemo-radiotherapy, the DDR drives cells toward cell cycle arrest and apoptosis. Some intracellular pathways, such as PI3K/Akt, which is overactivated in most cancers, could stimulate the DDR process and failure of chemo-radiotherapy with the increasing repair of damaged DNA. This signaling pathway induces DNA repair through the regulation of proteins that are involved in DDR like BRCA1, HMGB1, and P53. In this review, we will focus on the crosstalk of the PI3K/Akt and PIKKs involved in DDR and then discuss current achievements in the sensitization of cancer cells to chemo-radiotherapy by PI3K/Akt inhibitors.
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Affiliation(s)
- Forough Alemi
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Aydin Raei Sadigh
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Faezeh Malakoti
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yusuf Elhaei
- Department of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Seyed Hamed Ghaffari
- Department of Orthopedics, Shohada Medical Research & Training Hospital, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Masomeh Maleki
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
| | - Bahman Yousefi
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Niloufar Targhazeh
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Maryam Majidinia
- Solid Tumor Research Center, Urmia University of Medical Sciences, Urmia, Iran
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24
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Saar M, Narits J, Mägi L, Aaspõllu H, Vapper A, Kase M, Minajeva A, Vooder T, Tamm H, Buldakov M, Lavõgina D, Jaal J. Expression of immune checkpoint PD-1 in non-small cell lung cancer is associated with tumor cell DNA-dependent protein kinase. Mol Clin Oncol 2021; 15:211. [PMID: 34462666 PMCID: PMC8375025 DOI: 10.3892/mco.2021.2369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 06/28/2021] [Indexed: 01/27/2023] Open
Abstract
Immunotherapy using immune checkpoint inhibitors has demonstrated durable responses and has significantly improved survival in patients with non-small cell lung cancer (NSCLC). Moreover, immunotherapy is increasingly used in combination with cytotoxic treatments such as chemotherapy and radiotherapy. Although the combined treatments are more effective, the underling mechanisms that lead to higher antitumor activity are not fully understood. Therefore, the aim of the current retrospective study was to determine the relationship between expression of immune checkpoints [programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1)] and the enzyme DNA-dependent protein kinase (DNA-PK), which is part of a key pathway involved in the repair of cytotoxic cancer therapy induced damage. Surgically excised NSCLC tissues (n=121) were histologically examined for overall extent of inflammation (score 0-3). Expression levels of PD-1 (number of PD-1 positive cells), PD-L1 [tumor proportion score (TPS); %] and DNA-PK (proportion of DNA-PK positive tumor cells; %) were determined using immunohistochemistry. Expressions of these markers were compared in different clinicopathological subgroups and later used for nonparametric Spearman correlation analysis to determine associations. In patients with NSCLC, PD-1 was significantly expressed in males (P=0.030) and in patients with no or trivial inflammation scores (P=0.030). PD-L1 expression was also significantly higher in current smokers (P=0.025). Correlation analysis was based on the individual values of patients and revealed a significant association between one of the targets of immune checkpoint inhibitors and tumor cell DNA-PK. Tumors with higher numbers of PD-1 positive cells also demonstrated higher tumor cell DNA-PK expressions (P=0.027). The results demonstrated a significant positive correlation between the PD-1/PD-L1 axis and tumor cell DNA-PK expression in patients with NSCLC. Further studies are required to clarify the significance of this correlation and its effect on the efficacy of immunotherapy and cytotoxic cancer therapy combinations.
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Affiliation(s)
- Marika Saar
- Department of Pharmacy, Tartu University Hospital, Tartu 50406, Estonia.,Pharmacy Institute, University of Tartu, Tartu 50406, Estonia.,Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu 50406, Estonia
| | - Jaanika Narits
- Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu 50406, Estonia
| | - Laura Mägi
- Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu 50406, Estonia
| | - Hardi Aaspõllu
- Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu 50406, Estonia
| | - Annett Vapper
- Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu 50406, Estonia
| | - Marju Kase
- Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu 50406, Estonia.,Department of Radiotherapy and Oncological Therapy, Haematology and Oncology Clinic Tartu University Hospital, Tartu 50406, Estonia
| | - Ave Minajeva
- Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, Tartu 50411, Estonia
| | - Tõnu Vooder
- Helios Clinics, Center for Thoracic and Lung Surgery, D-47805 Krefeld, Germany
| | - Hannes Tamm
- Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, Tartu 50411, Estonia.,Pathology Department, Tartu University Hospital, Tartu 50406, Estonia
| | - Maksim Buldakov
- Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, Tartu 50411, Estonia.,Pathology Department, Tartu University Hospital, Tartu 50406, Estonia
| | - Darja Lavõgina
- Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu 50406, Estonia
| | - Jana Jaal
- Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu 50406, Estonia.,Department of Radiotherapy and Oncological Therapy, Haematology and Oncology Clinic Tartu University Hospital, Tartu 50406, Estonia
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25
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Faulhaber EM, Jost T, Symank J, Scheper J, Bürkel F, Fietkau R, Hecht M, Distel LV. Kinase Inhibitors of DNA-PK, ATM and ATR in Combination with Ionizing Radiation Can Increase Tumor Cell Death in HNSCC Cells While Sparing Normal Tissue Cells. Genes (Basel) 2021; 12:925. [PMID: 34204447 PMCID: PMC8235750 DOI: 10.3390/genes12060925] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 06/13/2021] [Accepted: 06/15/2021] [Indexed: 12/11/2022] Open
Abstract
(1) Kinase inhibitors (KI) targeting components of the DNA damage repair pathway are a promising new type of drug. Combining them with ionizing radiation therapy (IR), which is commonly used for treatment of head and neck tumors, could improve tumor control, but could also increase negative side effects on surrounding normal tissue. (2) The effect of KI of the DDR (ATMi: AZD0156; ATRi: VE-822, dual DNA-PKi/mTORi: CC-115) in combination with IR on HPV-positive and HPV-negative HNSCC and healthy skin cells was analyzed. Cell death and cell cycle arrest were determined using flow cytometry. Additionally, clonogenic survival and migration were analyzed. (3) Studied HNSCC cell lines reacted differently to DDRi. An increase in cell death for all of the malignant cells could be observed when combining IR and KI. Healthy fibroblasts were not affected by simultaneous treatment. Migration was partially impaired. Influence on the cell cycle varied between the cell lines and inhibitors; (4) In conclusion, a combination of DDRi with IR could be feasible for patients with HNSCC. Side effects on healthy cells are expected to be limited to normal radiation-induced response. Formation of metastases could be decreased because cell migration is impaired partially. The treatment outcome for HPV-negative tumors tends to be improved by combined treatment.
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Affiliation(s)
- Eva-Maria Faulhaber
- Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; (E.-M.F.); (T.J.); (J.S.); (J.S.); (F.B.); (R.F.); (M.H.)
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), 91054 Erlangen, Germany
| | - Tina Jost
- Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; (E.-M.F.); (T.J.); (J.S.); (J.S.); (F.B.); (R.F.); (M.H.)
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), 91054 Erlangen, Germany
| | - Julia Symank
- Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; (E.-M.F.); (T.J.); (J.S.); (J.S.); (F.B.); (R.F.); (M.H.)
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), 91054 Erlangen, Germany
| | - Julian Scheper
- Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; (E.-M.F.); (T.J.); (J.S.); (J.S.); (F.B.); (R.F.); (M.H.)
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), 91054 Erlangen, Germany
| | - Felix Bürkel
- Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; (E.-M.F.); (T.J.); (J.S.); (J.S.); (F.B.); (R.F.); (M.H.)
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), 91054 Erlangen, Germany
| | - Rainer Fietkau
- Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; (E.-M.F.); (T.J.); (J.S.); (J.S.); (F.B.); (R.F.); (M.H.)
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), 91054 Erlangen, Germany
| | - Markus Hecht
- Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; (E.-M.F.); (T.J.); (J.S.); (J.S.); (F.B.); (R.F.); (M.H.)
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), 91054 Erlangen, Germany
| | - Luitpold V. Distel
- Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; (E.-M.F.); (T.J.); (J.S.); (J.S.); (F.B.); (R.F.); (M.H.)
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), 91054 Erlangen, Germany
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26
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Suthar SK, Alam MM, Lee J, Monga J, Joseph A, Lee SY. Bioinformatic Analyses of Canonical Pathways of TSPOAP1 and its Roles in Human Diseases. Front Mol Biosci 2021; 8:667947. [PMID: 34212002 PMCID: PMC8239723 DOI: 10.3389/fmolb.2021.667947] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/21/2021] [Indexed: 12/19/2022] Open
Abstract
TSPO-associated protein 1 (TSPOAP1) is a cytoplasmic protein and is closely associated with its mitochondrial transmembrane protein partner translocator protein (TSPO). To decipher the canonical signalling pathways of TSPOAP1, its role in human diseases and disorders, and relationship with TSPO; expression analyses of TSPOAP1- and TSPO-associated human genes were performed by Qiagen Ingenuity Pathway Analysis (IPA). In the expression analysis, necroptosis and sirtuin signalling pathways, mitochondrial dysfunction, and inflammasome were the top canonical pathways for both TSPOAP1 and TSPO, confirming the close relationship between these two proteins. A distribution analysis of common proteins in all the canonical pathways predicted for TSPOAP1 revealed that tumor necrosis factor receptor 1 (TNFR1), vascular cell adhesion molecule 1 (VCAM1), cyclic AMP response element-binding protein 1 (CREB1), T-cell receptor (TCR), nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing 3 (NLRP3), DNA-dependent protein kinase (DNA-PK or PRKDC), and mitochondrial permeability transition pore (mPTP) were the major interaction partners of TSPOAP1, highlighting the role of TSPOAP1 in inflammation, particularly neuroinflammation. An analysis of the overlap between TSPO and TSPOAP1 Homo sapiens genes and top-ranked canonical pathways indicated that TSPO and TSPOAP1 interact via voltage-dependent anion-selective channels (VDAC1/2/3). A heat map analysis indicated that TSPOAP1 has critical roles in inflammatory, neuroinflammatory, psychiatric, and metabolic diseases and disorders, and cancer. Taken together, this information improves our understanding of the mechanism of action and biological functions of TSPOAP1 as well as its relationship with TSPO; furthermore, these results could provide new directions for in-depth functional studies of TSPOAP1 aimed at unmasking its detailed functions.
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Affiliation(s)
- Sharad Kumar Suthar
- Neuroscience Research Institute, Gachon University, Incheon, South Korea.,Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, India
| | | | - Jihye Lee
- Neuroscience Research Institute, Gachon University, Incheon, South Korea
| | - Jitender Monga
- Department of Urology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Alex Joseph
- Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, India
| | - Sang-Yoon Lee
- Neuroscience Research Institute, Gachon University, Incheon, South Korea.,Department of Neuroscience, College of Medicine, Gachon University, Incheon, South Korea
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27
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Yue X, Bai C, Xie D, Ma T, Zhou PK. DNA-PKcs: A Multi-Faceted Player in DNA Damage Response. Front Genet 2020; 11:607428. [PMID: 33424929 PMCID: PMC7786053 DOI: 10.3389/fgene.2020.607428] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/01/2020] [Indexed: 12/17/2022] Open
Abstract
DNA-dependent protein kinase catalytic subunit (DNA-PKcs) is a member of the phosphatidylinositol 3-kinase related kinase family, which can phosphorylate more than 700 substrates. As the core enzyme, DNA-PKcs forms the active DNA-PK holoenzyme with the Ku80/Ku70 heterodimer to play crucial roles in cellular DNA damage response (DDR). Once DNA double strand breaks (DSBs) occur in the cells, DNA-PKcs is promptly recruited into damage sites and activated. DNA-PKcs is auto-phosphorylated and phosphorylated by Ataxia-Telangiectasia Mutated at multiple sites, and phosphorylates other targets, participating in a series of DDR and repair processes, which determine the cells' fates: DSBs NHEJ repair and pathway choice, replication stress response, cell cycle checkpoints, telomeres length maintenance, senescence, autophagy, etc. Due to the special and multi-faceted roles of DNA-PKcs in the cellular responses to DNA damage, it is important to precisely regulate the formation and dynamic of its functional complex and activities for guarding genomic stability. On the other hand, targeting DNA-PKcs has been considered as a promising strategy of exploring novel radiosensitizers and killing agents of cancer cells. Combining DNA-PKcs inhibitors with radiotherapy can effectively enhance the efficacy of radiotherapy, offering more possibilities for cancer therapy.
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Affiliation(s)
- Xiaoqiao Yue
- School of Public Health, University of South China, Hengyang, China.,Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing, China
| | - Chenjun Bai
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing, China
| | - Dafei Xie
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing, China
| | - Teng Ma
- Department of Cellular and Molecular Biology, Beijing Chest Hospital, Capital Medical University/Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Ping-Kun Zhou
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing, China
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28
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Beyond DNA Repair: DNA-PKcs in Tumor Metastasis, Metabolism and Immunity. Cancers (Basel) 2020; 12:cancers12113389. [PMID: 33207636 PMCID: PMC7698146 DOI: 10.3390/cancers12113389] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/10/2020] [Accepted: 11/12/2020] [Indexed: 01/07/2023] Open
Abstract
The DNA-dependent protein kinase catalytic subunit (DNA-PKcs) is a key component of the DNA-PK complex that has a well-characterized function in the non-homologous end-joining repair of DNA double-strand breaks. Since its identification, a large body of evidence has demonstrated that DNA-PKcs is frequently overexpressed in cancer, plays a critical role in tumor development and progression, and is associated with poor prognosis of cancer patients. Intriguingly, recent studies have suggested novel functions beyond the canonical role of DNA-PKcs, which has transformed the paradigm of DNA-PKcs in tumorigenesis and has reinvigorated the interest to target DNA-PKcs for cancer treatment. In this review, we update recent advances in DNA-PKcs, in particular the emerging roles in tumor metastasis, metabolic dysregulation, and immune escape. We further discuss the possible molecular basis that underpins the pleiotropism of DNA-PKcs in cancer. Finally, we outline the biomarkers that may predict the therapeutic response to DNA-PKcs inhibitor therapy. Understanding the functional repertoire of DNA-PKcs will provide mechanistic insights of DNA-PKcs in malignancy and, more importantly, may revolutionize the design and utility of DNA-PKcs-based precision cancer therapy.
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29
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Zimmer Y, Reinhardt HC, Medová M. Editorial: Exploiting DNA Damage Response in the Era of Precision Oncology. Front Oncol 2020; 10:611127. [PMID: 33178619 PMCID: PMC7593708 DOI: 10.3389/fonc.2020.611127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 09/30/2020] [Indexed: 11/24/2022] Open
Affiliation(s)
- Yitzhak Zimmer
- Department of Radiation Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Department for BioMedical Research, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Hans Christian Reinhardt
- Department of Hematology and Stem Cell Transplantation, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.,German Consortium for Translational Cancer Research (DKTK), Medical Faculty, University of Duisburg-Essen, Essen, Germany
| | - Michaela Medová
- Department of Radiation Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Department for BioMedical Research, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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30
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Lee JA, Ayat N, Sun Z, Tofilon PJ, Lu ZR, Camphausen K. Improving Radiation Response in Glioblastoma Using ECO/siRNA Nanoparticles Targeting DNA Damage Repair. Cancers (Basel) 2020; 12:cancers12113260. [PMID: 33158243 PMCID: PMC7694254 DOI: 10.3390/cancers12113260] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 10/30/2020] [Accepted: 10/30/2020] [Indexed: 02/06/2023] Open
Abstract
Simple Summary Glioblastoma (GBM) is the most common form of brain cancer and among the most lethal of human cancers. Radiation therapy is a mainstay in the standard of care for GBM, killing tumor cells by creating DNA damage. Inhibiting DNA damage repair (DDR) proteins enhances radiation therapy by not allowing tumor cells to repair the DNA damage caused by radiation. The aim of our study was to investigate whether the novel nanoparticle material, ECO, could be used to deliver small interfering RNA (siRNA) to GBM tumor cells and temporarily reduce the production of DDR proteins to improve radiation therapy outcomes. SiRNAs can be designed to target an innumerable number of genes and with the right delivery vehicle can be used in a variety of disease settings. Our work provides support for the use of the novel ECO material for delivery of siRNA in GBM. Abstract Radiation therapy is a mainstay in the standard of care for glioblastoma (GBM), thus inhibiting the DNA damage response (DDR) is a major strategy to improve radiation response and therapeutic outcomes. Small interfering RNA (siRNA) therapy holds immeasurable potential for the treatment of GBM, however delivery of the siRNA payload remains the largest obstacle for clinical implementation. Here we demonstrate the effectiveness of the novel nanomaterial, ECO (1-aminoethylimino[bis(N-oleoylcysteinylaminoethyl) propionamide]), to deliver siRNA targeting DDR proteins ataxia telangiectasia mutated and DNA-dependent protein kinase (DNApk-cs) for the radiosensitzation of GBM in vitro and in vivo. ECO nanoparticles (NPs) were shown to efficiently deliver siRNA and silence target protein expression in glioma (U251) and glioma stem cell lines (NSC11, GBMJ1). Importantly, ECO NPs displayed no cytotoxicity and minimal silencing of genes in normal astrocytes. Treatment with ECO/siRNA NPs and radiation resulted in the prolonged presence of γH2AX foci, indicators of DNA damage, and increased radiosensitivity in all tumor cell lines. In vivo, intratumoral injection of ECO/siDNApk-cs NPs with radiation resulted in a significant increase in survival compared with injection of NPs alone. These data suggest the ECO nanomaterial can effectively deliver siRNA to more selectively target and radiosensitize tumor cells to improve therapeutic outcomes in GBM.
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Affiliation(s)
- Jennifer A. Lee
- Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (P.J.T.); (K.C.)
- Correspondence:
| | - Nadia Ayat
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44140, USA; (N.A.); (Z.S.); (Z.-R.L.)
| | - Zhanhu Sun
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44140, USA; (N.A.); (Z.S.); (Z.-R.L.)
| | - Philip J. Tofilon
- Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (P.J.T.); (K.C.)
| | - Zheng-Rong Lu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44140, USA; (N.A.); (Z.S.); (Z.-R.L.)
| | - Kevin Camphausen
- Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; (P.J.T.); (K.C.)
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