1
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Rana M, Perotti A, Bisset LM, Smith JD, Lamden E, Khan Z, Ismail MK, Ellis K, Armstrong KA, Hodder SL, Bertoli C, Meneguello L, de Bruin RAM, Morris JR, Romero-Canelon I, Tucker JHR, Hodges NJ. A ferrocene-containing nucleoside analogue targets DNA replication in pancreatic cancer cells. Metallomics 2022; 14:mfac041. [PMID: 35689667 PMCID: PMC9320222 DOI: 10.1093/mtomcs/mfac041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 05/11/2022] [Indexed: 11/14/2022]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is a disease that remains refractory to existing treatments including the nucleoside analogue gemcitabine. In the current study we demonstrate that an organometallic nucleoside analogue, the ferronucleoside 1-(S,Rp), is cytotoxic in a panel of PDAC cell lines including gemcitabine-resistant MIAPaCa2, with IC50 values comparable to cisplatin. Biochemical studies show that the mechanism of action is inhibition of DNA replication, S-phase cell cycle arrest and stalling of DNA-replication forks, which were directly observed at single molecule resolution by DNA-fibre fluorography. In agreement with this, transcriptional changes following treatment with 1-(S,Rp) include activation of three of the four genes (HUS1, RAD1, RAD17) of the 9-1-1 check point complex clamp and two of the three genes (MRE11, NBN) that form the MRN complex as well as activation of multiple downstream targets. Furthermore, there was evidence of phosphorylation of checkpoint kinases 1 and 2 as well as RPA1 and gamma H2AX, all of which are considered biochemical markers of replication stress. Studies in p53-deficient cell lines showed activation of CDKN1A (p21) and GADD45A by 1-(S,Rp) was at least partially independent of p53. In conclusion, because of its potency and activity in gemcitabine-resistant cells, 1-(S,Rp) is a promising candidate molecule for development of new treatments for PDAC.
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Affiliation(s)
- Marium Rana
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
- School of Chemistry, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Alessio Perotti
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Lucy M Bisset
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - James D Smith
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Emma Lamden
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Zahra Khan
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Media K Ismail
- Department of pharmacy, college of pharmacy, Knowledge University, 44001 Erbil, Kurdistan Region, Iraq
| | - Katherine Ellis
- Institute of Cancer and Genomic Sciences, and The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Katie A Armstrong
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Samantha L Hodder
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Cosetta Bertoli
- MRC Laboratory or Molecular Cell Biology, University College London, London, WC1E 6BT, UK
| | - Leticia Meneguello
- MRC Laboratory or Molecular Cell Biology, University College London, London, WC1E 6BT, UK
| | - Robertus A M de Bruin
- MRC Laboratory or Molecular Cell Biology, University College London, London, WC1E 6BT, UK
| | - Joanna R Morris
- Institute of Cancer and Genomic Sciences, and The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Isolda Romero-Canelon
- School of Pharmacy, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - James H R Tucker
- School of Chemistry, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Nikolas J Hodges
- School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
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2
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Abstract
AbstractsChk1 inhibition can selectively improve gemcitabine sensitivity in p53-deficient cells by checkpoints abrogation throughout the cell cycle. However, the dependency of p53 status is still controversial for predicting the priority of such synergy. This study aimed at expounding the differential therapeutic properties of gemcitabine sensitization by Chk1 inhibition potentially affected by p53 status. We introduced wild-type and hotspot mutant p53 in p53-null H1299 cells, and quantified combination of gemcitabine with two Chk1 inhibitors using Chou-Talalay method. As a result, depletion of p53 preferentially produced synergistic effects. Wild-type and mutant p53 also conferred drug synergy but gradually showed compromised potency of growth inhibition. These data provide increased evidence that p53 status is a weak predictor for identifying an effective synergy, but genetic loss of p53 is relatively favorable for combination treatment. Further efforts on validation in more cell lines and clinical models could improve the predictive validity in this study.
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Affiliation(s)
- Shanlong Pan
- Department of Pharmacy, College of Medicine, Yangzhou University, Yangzhou, China
| | - Rongrong Li
- Department of Pharmacy, College of Medicine, Yangzhou University, Yangzhou, China
| | - Li Tao
- Department of Pharmacy, College of Medicine, Yangzhou University, Yangzhou, China
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3
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Endersby R, Whitehouse J, Pribnow A, Kuchibhotla M, Hii H, Carline B, Gande S, Stripay J, Ancliffe M, Howlett M, Schoep T, George C, Andradas C, Dyer P, Schluck M, Patterson B, Tacheva-Gigorova SK, Cooper MN, Robinson G, Stewart C, Pfister SM, Kool M, Milde T, Gajjar A, Johns T, Wechsler-Reya RJ, Roussel MF, Gottardo NG. Small-molecule screen reveals synergy of cell cycle checkpoint kinase inhibitors with DNA-damaging chemotherapies in medulloblastoma. Sci Transl Med 2021; 13:13/577/eaba7401. [PMID: 33472956 DOI: 10.1126/scitranslmed.aba7401] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 07/24/2020] [Accepted: 11/30/2020] [Indexed: 12/19/2022]
Abstract
Medulloblastoma (MB) consists of four core molecular subgroups with distinct clinical features and prognoses. Treatment consists of surgery, followed by radiotherapy and cytotoxic chemotherapy. Despite this intensive approach, outcome remains dismal for patients with certain subtypes of MB, namely, MYC-amplified Group 3 and TP53-mutated SHH. Using high-throughput assays, six human MB cell lines were screened against a library of 3208 unique compounds. We identified 45 effective compounds from the screen and found that cell cycle checkpoint kinase (CHK1/2) inhibition synergistically enhanced the cytotoxic activity of clinically used chemotherapeutics cyclophosphamide, cisplatin, and gemcitabine. To identify the best-in-class inhibitor, multiple CHK1/2 inhibitors were assessed in mice bearing intracranial MB. When combined with DNA-damaging chemotherapeutics, CHK1/2 inhibition reduced tumor burden and increased survival of animals with high-risk MB, across multiple different models. In total, we tested 14 different models, representing distinct MB subgroups, and data were validated in three independent laboratories. Pharmacodynamics studies confirmed central nervous system penetration. In mice, combination treatment significantly increased DNA damage and apoptosis compared to chemotherapy alone, and studies with cultured cells showed that CHK inhibition disrupted chemotherapy-induced cell cycle arrest. Our findings indicated CHK1/2 inhibition, specifically with LY2606368 (prexasertib), has strong chemosensitizing activity in MB that warrants further clinical investigation. Moreover, these data demonstrated that we developed a robust and collaborative preclinical assessment platform that can be used to identify potentially effective new therapies for clinical evaluation for pediatric MB.
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Affiliation(s)
- Raelene Endersby
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia. .,Division of Paediatrics/Centre for Child Health Research, Medical School, University of Western Australia, Crawley, WA 6009, Australia
| | - Jacqueline Whitehouse
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia.,Division of Paediatrics/Centre for Child Health Research, Medical School, University of Western Australia, Crawley, WA 6009, Australia
| | - Allison Pribnow
- Division of Hematology/Oncology, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, CA 94305, USA
| | - Mani Kuchibhotla
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia
| | - Hilary Hii
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia
| | - Brooke Carline
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia
| | - Suresh Gande
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia
| | - Jennifer Stripay
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, TN 38103, USA
| | - Mathew Ancliffe
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia
| | - Meegan Howlett
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia.,Division of Paediatrics/Centre for Child Health Research, Medical School, University of Western Australia, Crawley, WA 6009, Australia
| | - Tobias Schoep
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia
| | - Courtney George
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia
| | - Clara Andradas
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia.,Division of Paediatrics/Centre for Child Health Research, Medical School, University of Western Australia, Crawley, WA 6009, Australia
| | - Patrick Dyer
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia.,Division of Paediatrics/Centre for Child Health Research, Medical School, University of Western Australia, Crawley, WA 6009, Australia
| | - Marjolein Schluck
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia.,Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525 GA, Netherlands
| | - Brett Patterson
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia
| | - Silvia K Tacheva-Gigorova
- Tumor Initiation and Maintenance Program, NCI-Designated Cancer Center, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Matthew N Cooper
- Biometrics, Telethon Kids Institute, University of Western Australia, Nedlands, WA 6009, Australia
| | - Giles Robinson
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN 38103, USA
| | - Clinton Stewart
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, TN 38103, USA
| | - Stefan M Pfister
- Hopp Children's Cancer Center (KiTZ) and German Cancer Research Center (DKFZ), Heidelberg 69120, Germany.,Department of Pediatric Hematology and Oncology, Heidelberg University Hospital, Heidelberg 69120, Germany
| | - Marcel Kool
- Hopp Children's Cancer Center (KiTZ) and German Cancer Research Center (DKFZ), Heidelberg 69120, Germany.,Princess Máxima Center for Pediatric Oncology, Utrecht 3584 CS, Netherlands
| | - Till Milde
- Hopp Children's Cancer Center (KiTZ) and German Cancer Research Center (DKFZ), Heidelberg 69120, Germany.,Department of Pediatric Hematology and Oncology, Heidelberg University Hospital, Heidelberg 69120, Germany
| | - Amar Gajjar
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN 38103, USA
| | - Terrance Johns
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia.,Division of Paediatrics/Centre for Child Health Research, Medical School, University of Western Australia, Crawley, WA 6009, Australia
| | - Robert J Wechsler-Reya
- Tumor Initiation and Maintenance Program, NCI-Designated Cancer Center, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Martine F Roussel
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, TN 38103, USA
| | - Nicholas G Gottardo
- Brain Tumour Research Program, Telethon Kids Institute, Nedlands, WA 6009, Australia. .,Division of Paediatrics/Centre for Child Health Research, Medical School, University of Western Australia, Crawley, WA 6009, Australia.,Department of Pediatric and Adolescent Oncology/Hematology, Perth Children's Hospital, Nedlands, WA 6009, Australia
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4
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Fernandes SG, Shah P, Khattar E. Recent Advances in Therapeutic Application of DNA Damage Response Inhibitors against Cancer. Anticancer Agents Med Chem 2021; 22:469-484. [PMID: 34102988 DOI: 10.2174/1871520621666210608105735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/02/2021] [Accepted: 02/22/2021] [Indexed: 11/22/2022]
Abstract
DNA integrity is continuously challenged by intrinsic cellular processes and environmental agents. To overcome this genomic damage, cells have developed multiple signaling pathways collectively named as DNA damage response (DDR) and composed of three components: (i) sensor proteins, which detect DNA damage, (ii) mediators that relay the signal downstream and recruit the repair machinery, and (iii) the repair proteins, which restore the damaged DNA. A flawed DDR and failure to repair the damage lead to the accumulation of genetic lesions and increased genomic instability, which is recognized as a hallmark of cancer. Cancer cells tend to harbor increased mutations in DDR genes and often have fewer DDR pathways than normal cells. This makes cancer cells more dependent on particular DDR pathways and thus become more susceptible to compounds inhibiting those pathways compared to normal cells, which have all the DDR pathways intact. Understanding the roles of different DDR proteins in the DNA damage response and repair pathways and identification of their structures have paved the way for the development of their inhibitors as targeted cancer therapy. In this review, we describe the major participants of various DDR pathways, their significance in carcinogenesis, and focus on the inhibitors developed against several key DDR proteins.
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Affiliation(s)
- Stina George Fernandes
- Sunandan Divatia School of Science, SVKM's NMIMS (Deemed to be) University, Mumbai, India
| | - Prachi Shah
- Sunandan Divatia School of Science, SVKM's NMIMS (Deemed to be) University, Mumbai, India
| | - Ekta Khattar
- Sunandan Divatia School of Science, SVKM's NMIMS (Deemed to be) University, Mumbai, India
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5
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Ostergaard J, Jonart LM, Ebadi M, Koppenhafer SL, Gordon DJ, Gordon PM. Preclinical efficacy of prexasertib in acute lymphoblastic leukemia. Br J Haematol 2021; 194:1094-1098. [PMID: 34096630 DOI: 10.1111/bjh.17610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 05/11/2021] [Indexed: 11/28/2022]
Affiliation(s)
- Jason Ostergaard
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, University of Minnesota, Minneapolis, MN, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Leslie M Jonart
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, University of Minnesota, Minneapolis, MN, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Maryam Ebadi
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, University of Minnesota, Minneapolis, MN, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Stacia L Koppenhafer
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Iowa, Iowa City, IA, USA
| | - David J Gordon
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Iowa, Iowa City, IA, USA
| | - Peter M Gordon
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, University of Minnesota, Minneapolis, MN, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
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6
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Basukala O, Sarabia-Vega V, Banks L. Human papillomavirus oncoproteins and post-translational modifications: generating multifunctional hubs for overriding cellular homeostasis. Biol Chem 2021; 401:585-599. [PMID: 31913845 DOI: 10.1515/hsz-2019-0408] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 12/19/2019] [Indexed: 11/15/2022]
Abstract
Human papillomaviruses (HPVs) are major human carcinogens, causing around 5% of all human cancers, with cervical cancer being the most important. These tumors are all driven by the two HPV oncoproteins E6 and E7. Whilst their mechanisms of action are becoming increasingly clear through their abilities to target essential cellular tumor suppressor and growth control pathways, the roles that post-translational modifications (PTMs) of E6 and E7 play in the regulation of these activities remain unclear. Here, we discuss the direct consequences of some of the most common PTMs of E6 and E7, and how this impacts upon the multi-functionality of these viral proteins, and thereby contribute to the viral life cycle and to the induction of malignancy. Furthermore, it is becoming increasingly clear that these modifications, may, in some cases, offer novel routes for therapeutic intervention in HPV-induced disease.
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Affiliation(s)
- Om Basukala
- International Centre for Genetic Engineering and Biotechnology, AREA Science Park, Padriciano 99, I-34149Trieste, Italy
| | - Vanessa Sarabia-Vega
- International Centre for Genetic Engineering and Biotechnology, AREA Science Park, Padriciano 99, I-34149Trieste, Italy
| | - Lawrence Banks
- International Centre for Genetic Engineering and Biotechnology, AREA Science Park, Padriciano 99, I-34149Trieste, Italy
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7
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Peng X, Wei Z, Gerweck LE. Making radiation therapy more effective in the era of precision medicine. PRECISION CLINICAL MEDICINE 2020; 3:272-283. [PMID: 35692625 PMCID: PMC8982539 DOI: 10.1093/pcmedi/pbaa038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 11/18/2020] [Accepted: 11/22/2020] [Indexed: 02/05/2023] Open
Abstract
Cancer has become a leading cause of death and constitutes an enormous burden worldwide. Radiation is a principle treatment modality used alone or in combination with other forms of therapy, with 50%–70% of cancer patients receiving radiotherapy at some point during their illness. It has been suggested that traditional radiotherapy (daily fractions of approximately 1.8–2 Gy over several weeks) might select for radioresistant tumor cell sub-populations, which, if not sterilized, give rise to local treatment failure and distant metastases. Thus, the challenge is to develop treatment strategies and schedules to eradicate the resistant subpopulation of tumorigenic cells rather than the predominant sensitive tumor cell population. With continued technological advances including enhanced conformal treatment technology, radiation oncologists can increasingly maximize the dose to tumors while sparing adjacent normal tissues, to limit toxicity and damage to the latter. Increased dose conformality also facilitates changes in treatment schedules, such as changes in dose per treatment fraction and number of treatment fractions, to enhance the therapeutic ratio. For example, the recently developed large dose per fraction treatment schedules (hypofractionation) have shown clinical advantage over conventional treatment schedules in some tumor types. Experimental studies suggest that following large acute doses of radiation, recurrent tumors, presumably sustained by the most resistant tumor cell populations, may in fact be equally or more radiation sensitive than the primary tumor. In this review, we summarize the related advances in radiotherapy, including the increasing understanding of the molecular mechanisms of radioresistance, and the targeting of these mechanisms with potent small molecule inhibitors, which may selectively sensitize tumor cells to radiation.
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Affiliation(s)
- Xingchen Peng
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Zhigong Wei
- Department of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Leo E Gerweck
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
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8
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Nair J, Huang TT, Murai J, Haynes B, Steeg PS, Pommier Y, Lee JM. Resistance to the CHK1 inhibitor prexasertib involves functionally distinct CHK1 activities in BRCA wild-type ovarian cancer. Oncogene 2020; 39:5520-5535. [PMID: 32647134 PMCID: PMC7426265 DOI: 10.1038/s41388-020-1383-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 06/15/2020] [Accepted: 06/25/2020] [Indexed: 12/16/2022]
Abstract
High grade serous ovarian cancer (HGSOC) is a fatal gynecologic malignancy in the U.S. with limited treatment options. New therapeutic strategies include targeting of the cell cycle checkpoints, e.g., ATR and CHK1. We recently reported a promising clinical activity of the CHK1 inhibitor (CHK1i) prexasertib monotherapy in BRCA wild-type (BRCAwt) HGSOC patients. In this study, biopsies of treated patients and cell line models were used to investigate possible mechanisms of resistance to CHK1i. We report that BRCAwt HGSOC develops resistance to prexasertib monotherapy via a prolonged G2 delay induced by lower CDK1/CyclinB1 activity, thus preventing cells from mitotic catastrophe and cell death. On the other hand, we noted CHK1's regulation on RAD51-mediated homologous recombination (HR) repair was not altered in CHK1i-resistant cells. Therefore, CHK1i sensitizes CHK1i-resistant cells to DNA damaging agents such as gemcitabine or hydroxyurea by inhibition of HR. In summary, our results demonstrate new mechanistic insights of functionally distinct CHK1 activities and highlight a potential combination treatment approach to overcome CHK1i resistance in BRCAwt HGSOC.
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Affiliation(s)
- Jayakumar Nair
- Women's Malignancies Branch, National Institutes of Health, Bethesda, 20892, MD, USA.
| | - Tzu-Ting Huang
- Women's Malignancies Branch, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Junko Murai
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Brittany Haynes
- Women's Malignancies Branch, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Patricia S Steeg
- Women's Malignancies Branch, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Yves Pommier
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Jung-Min Lee
- Women's Malignancies Branch, National Institutes of Health, Bethesda, 20892, MD, USA
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Warren NJH, Eastman A. Comparison of the different mechanisms of cytotoxicity induced by checkpoint kinase I inhibitors when used as single agents or in combination with DNA damage. Oncogene 2020; 39:1389-1401. [PMID: 31659257 PMCID: PMC7023985 DOI: 10.1038/s41388-019-1079-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/14/2019] [Accepted: 10/15/2019] [Indexed: 12/31/2022]
Abstract
Inhibition of the DNA damage response is an emerging strategy to treat cancer. Understanding how DNA damage response inhibitors cause cytotoxicity in cancer cells is crucial to their further clinical development. This review focuses on three different mechanisms of cell killing by checkpoint kinase I inhibitors (CHK1i). DNA damage induced by chemotherapy drugs, such as topoisomerase I inhibitors, results in S and G2 phase arrest. Addition of CHK1i promotes cell cycle progression before repair is completed resulting in mitotic catastrophe. Ribonucleotide reductase inhibitors such as gemcitabine also arrest cells in S phase by preventing dNTP synthesis. Addition of CHK1i re-activates the DNA helicase to unwind DNA, but in the absence of dNTPs, this leads to excessive single-strand DNA that exceeds the protective capacity of the single-strand-binding protein RPA. Unprotected DNA is subjected to nuclease cleavage, resulting in replication catastrophe. CHK1i alone also kills a subset of cell lines through MRE11 and MUS81-mediated DNA cleavage in S phase cells. The choice of mechanism depends on the activation state of CDK2. Low level activation of CDK2 mediates helicase activation, cell cycle progression, and both replication and mitotic catastrophe. In contrast, high CDK2 activity is required for sensitivity to CHK1i as monotherapy. This high CDK2 activity threshold usually occurs late in the cell cycle to prepare for mitosis, but in CHK1i-sensitive cells, high activity can be attained in early S phase, resulting in DNA cleavage and cell death. This sensitivity to CHK1i has previously been associated with endogenous replication stress, but the dependence on high CDK2 activity, as well as MRE11, contradicts this hypothesis. The major unresolved question is why some cell lines fail to restrain their high CDK2 activity and hence succumb to CHK1i in S phase. Resolving this question will facilitate stratification of patients for treatment with CHK1i as monotherapy.
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Affiliation(s)
- Nicholas J H Warren
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH, 03756, USA
| | - Alan Eastman
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH, 03756, USA.
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH, 03756, USA.
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10
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Lowery CD, Dowless M, Renschler M, Blosser W, VanWye AB, Stephens JR, Iversen PW, Lin AB, Beckmann RP, Krytska K, Cole KA, Maris JM, Hawkins DS, Rubin BP, Kurmasheva RT, Houghton PJ, Gorlick R, Kolb EA, Kang MH, Reynolds CP, Erickson SW, Teicher BA, Smith MA, Stancato LF. Broad Spectrum Activity of the Checkpoint Kinase 1 Inhibitor Prexasertib as a Single Agent or Chemopotentiator Across a Range of Preclinical Pediatric Tumor Models. Clin Cancer Res 2018; 25:2278-2289. [PMID: 30563935 DOI: 10.1158/1078-0432.ccr-18-2728] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 11/13/2018] [Accepted: 12/14/2018] [Indexed: 12/21/2022]
Abstract
PURPOSE Checkpoint kinase 1 (CHK1) inhibitors potentiate the DNA-damaging effects of cytotoxic therapies and/or promote elevated levels of replication stress, leading to tumor cell death. Prexasertib (LY2606368) is a CHK1 small-molecule inhibitor under clinical evaluation in multiple adult and pediatric cancers. In this study, prexasertib was tested in a large panel of preclinical models of pediatric solid malignancies alone or in combination with chemotherapy. EXPERIMENTAL DESIGN DNA damage and changes in cell signaling following in vitro prexasertib treatment in pediatric sarcoma cell lines were analyzed by Western blot and high content imaging. Antitumor activity of prexasertib as a single agent or in combination with different chemotherapies was explored in cell line-derived (CDX) and patient-derived xenograft (PDX) mouse models representing nine different pediatric cancer histologies. RESULTS Pediatric sarcoma cell lines were highly sensitive to prexasertib treatment in vitro, resulting in activation of the DNA damage response. Two PDX models of desmoplastic small round cell tumor and one malignant rhabdoid tumor CDX model responded to prexasertib with complete regression. Prexasertib monotherapy also elicited robust responses in mouse models of rhabdomyosarcoma. Concurrent administration with chemotherapy was sufficient to overcome innate resistance or prevent acquired resistance to prexasertib in preclinical models of neuroblastoma, osteosarcoma, and Ewing sarcoma, or alveolar rhabdomyosarcoma, respectively. CONCLUSIONS Prexasertib has significant antitumor effects as a monotherapy or in combination with chemotherapy in multiple preclinical models of pediatric cancer. These findings support further investigation of prexasertib in pediatric malignancies.
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Affiliation(s)
- Caitlin D Lowery
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana
| | - Michele Dowless
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana
| | - Matthew Renschler
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana
| | - Wayne Blosser
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana
| | - Alle B VanWye
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana
| | | | - Philip W Iversen
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana
| | - Aimee Bence Lin
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana
| | | | - Kateryna Krytska
- The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Kristina A Cole
- The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - John M Maris
- The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Douglas S Hawkins
- Division of Hematology/Oncology, Seattle Children's Hospital, Seattle, Washington
| | - Brian P Rubin
- Departments of Pathology and Cancer Biology, Robert J Tomsich Pathology and Laboratory Medicine Institute and Cleveland Clinic, Cleveland, Ohio
| | | | - Peter J Houghton
- Greehey Children's Cancer Research Institute, San Antonio, Texas
| | | | - E Anders Kolb
- Nemours Center for Cancer and Blood Disorders, Wilmington, Delaware
| | - Min H Kang
- Texas Tech University Health Sciences Center, Lubbock, Texas
| | | | | | | | | | - Louis F Stancato
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana.
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11
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Kaina B, Izzotti A, Xu J, Christmann M, Pulliero A, Zhao X, Dobreanu M, Au WW. Inherent and toxicant-provoked reduction in DNA repair capacity: A key mechanism for personalized risk assessment, cancer prevention and intervention, and response to therapy. Int J Hyg Environ Health 2018; 221:993-1006. [PMID: 30041861 DOI: 10.1016/j.ijheh.2018.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 07/03/2018] [Accepted: 07/04/2018] [Indexed: 02/05/2023]
Abstract
Genomic investigations reveal novel evidence which indicates that genetic predisposition and inherent drug response are key factors for development of cancer and for poor response to therapy. However, mechanisms for these outcomes and interactions with environmental factors have not been well-characterized. Therefore, cancer risk, prevention, intervention and prognosis determinations have still mainly been based on population, rather than on individualized, evaluations. The objective of this review was to demonstrate that a key mechanism which contributes to the determination is inherent and/or toxicant-provoked reduction in DNA repair capacity. In addition, functional and quantitative determination of DNA repair capacity on an individual basis would dramatically change the evaluation and management of health problems from a population to a personalized basis. In this review, justifications for the scenario were delineated. Topics to be presented include assays for detection of functional DNA repair deficiency, mechanisms for DNA repair defects, toxicant-perturbed DNA repair capacity, epigenetic mechanisms (methylation and miRNA expression) for alteration of DNA repair function, and bioinformatics approach to analyze large amount of genomic data. Information from these topics has recently been and will be used for better understanding of cancer causation and of response to therapeutic interventions. Consequently, innovative genomic- and mechanism-based evidence can be increasingly used to develop more precise cancer risk assessment, and target-specific and personalized medicine.
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Affiliation(s)
| | - Alberto Izzotti
- University of Genoa, Genoa, Italy; IRCCS Policlinico San Martino Genoa, Italy
| | - Jianzhen Xu
- Shantou University Medical College, Shantou, China
| | | | | | - Xing Zhao
- Shantou University Medical College, Shantou, China
| | | | - William W Au
- Shantou University Medical College, Shantou, China; University of Medicine and Pharmacy, Tirgu Mures, Romania; University of Texas Medical Branch, Galveston, TX, USA.
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12
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Mirza-Aghazadeh-Attari M, Darband SG, Kaviani M, Mihanfar A, Aghazadeh Attari J, Yousefi B, Majidinia M. DNA damage response and repair in colorectal cancer: Defects, regulation and therapeutic implications. DNA Repair (Amst) 2018; 69:34-52. [PMID: 30055507 DOI: 10.1016/j.dnarep.2018.07.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/15/2018] [Accepted: 07/15/2018] [Indexed: 12/11/2022]
Abstract
DNA damage response, a key factor involved in maintaining genome integrity and stability, consists of several kinase-dependent signaling pathways, which sense and transduce DNA damage signal. The severity of damage appears to determine DNA damage responses, which can include cell cycle arrest, damage repair and apoptosis. A number of recent studies have demonstrated that defection in signaling through this network is thought to be an underlying mechanism behind the development and progression of various types of human malignancies, including colorectal cancer. In this review, colorectal cancer and its molecular pathology as well as DNA damage response is briefly introduced. Finally, the involvement of key components of this network in the initiation/progression, prognosis, response to treatment and development of drug resistance is comprehensively discussed.
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Affiliation(s)
- Mohammad Mirza-Aghazadeh-Attari
- Aging Research Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saber Ghazizadeh Darband
- Danesh Pey Hadi Co., Health Technology Development Center, Urmia University of Medical Sciences, Urmia, Iran
| | - Mojtaba Kaviani
- School of Nutrition and Dietetics, Acadia University, Wolfville, Nova Scotia, Canada
| | - Ainaz Mihanfar
- Stem Cell and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Bahman Yousefi
- Molecular Medicine Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Maryam Majidinia
- Solid Tumor Research Center, Urmia University of Medical Sciences, Urmia, Iran.
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13
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Dai CH, Wang Y, Chen P, Jiang Q, Lan T, Li MY, Su JY, Wu Y, Li J. Suppression of the FA pathway combined with CHK1 inhibitor hypersensitize lung cancer cells to gemcitabine. Sci Rep 2017; 7:15031. [PMID: 29118324 PMCID: PMC5678185 DOI: 10.1038/s41598-017-15172-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 10/23/2017] [Indexed: 01/15/2023] Open
Abstract
The combination of platinum and gemcitabine is one of the standard regimens in the treatment of advanced lung squamous carcinoma (LSC). Resistance to gemcitabine is main barrier to the successful treatment of LSC. In this study, we showed that suppression of the Fanconi anemia (FA) pathway increased the sensitivity of two LSC cell lines SK-MES-1 and KLN205 to gemcitabine. Moreover, we found that the CHK1 pathway and the FA pathway are functionally compensatory in the repair of DNA damage in the LSC cell lines. Inactivation of one of the two pathways led to DNA damage, triggering compensatory activation of other pathway. Furthermore, we demonstrated that FANCD2 depletion combined with CHK1 inhibitor MK-8776 significantly potentiated the cytotoxicity of gemcitabine to the two LSC cell lines, compared to individual FANCD2 depletion or MK-8776 treatment. The enhanced effect of gemcitabine-chemosensitization was accompanied by loss of DNA repair function and accumulation of DNA single strand breaks and double strand breaks, in parallel with obvious increase of caspase-3 dependent apoptosis. Our results indicate that the enhancement effect of FANCD2 depletion combined with CHK1 inhibitor in sensitizing the LCS cells to gemcitabine supports the FA pathway and CHK1 as two therapeutic targets for improvement of anti-tumor regimens in treatment of LSC.
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Affiliation(s)
- Chun-Hua Dai
- Department of Radiation Oncology, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Yi Wang
- Center of Experimental Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Ping Chen
- Department of Pulmonary Medicine, Affitialed Hospital of Jiangsu University, Zhenjiang, China
| | - Qian Jiang
- Center of Experimental Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Ting Lan
- Institute of Medical Science, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Mei-Yu Li
- Department of Pulmonary Medicine, Affitialed Hospital of Jiangsu University, Zhenjiang, China
| | - Jin-Yu Su
- Department of Pulmonary Medicine, Affitialed Hospital of Jiangsu University, Zhenjiang, China
| | - Yan Wu
- Institute of Medical Science, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Jian Li
- Department of Pulmonary Medicine, Affitialed Hospital of Jiangsu University, Zhenjiang, China.
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14
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Jing W, Song N, Liu Y, Qu X, Hou K, Yang X, Che X. DNA methyltransferase 3a modulates chemosensitivity to gemcitabine and oxaliplatin via CHK1 and AKT in p53‑deficient pancreatic cancer cells. Mol Med Rep 2017; 17:117-124. [PMID: 29115606 PMCID: PMC5780073 DOI: 10.3892/mmr.2017.7923] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Accepted: 08/01/2017] [Indexed: 12/26/2022] Open
Abstract
The aberrant expression of DNA methyltransferases (DNMTs) has been considered to be associated with pancreatic carcinogenesis and progression. DNMT3a is widely involved in cell proliferation and cell cycle progression in pancreatic ductal adenocarcinoma (PDAC) cells. However, its regulation of chemosensitivity to gemcitabine (GEM) and oxaliplatin (OXA) in p53‑deficient PDAC remains unclear. In the present study, the effect and mechanisms of DNMT3a on GEM and OXA chemosensitivity in p53‑deficient PDAC cells were investigated using MTT assay, cell cycle analysis, apoptosis analysis and western blotting. The treatment of GEM and OXA induced S phase arrest by DNA damage, and enhanced the activation of the AKT signaling pathway in Panc‑1 cells. Downregulation of DNMT3a increased the chemosensitivity to both GEM and OXA in Panc‑1 cells. DNMT3a depletion distinctly abolished S phase arrest induced by GEM and OXA. Further research demonstrated that activation inhibition of CHK1 and AKT, as well as an increase in apoptosis, were involved in DNMT3a‑mediated chemosensitivity to GEM and OXA. Taken together, these data demonstrated that DNMT3a serves a crucial role in the regulation of chemosensitivity to GEM and OXA, and suggests a promising therapeutic target for p53‑deficient PDAC.
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Affiliation(s)
- Wei Jing
- Department of Oncology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Na Song
- Department of Medical Oncology, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Yunpeng Liu
- Department of Medical Oncology, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Xiujuan Qu
- Department of Medical Oncology, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Kezuo Hou
- Department of Medical Oncology, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Xianghong Yang
- Department of Pathology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Xiaofang Che
- Department of Medical Oncology, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
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15
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Kawamura D, Takemoto Y, Nishimoto A, Ueno K, Hosoyama T, Shirasawa B, Tanaka T, Kugimiya N, Harada E, Hamano K. Enhancement of cytotoxic effects of gemcitabine by Dclk1 inhibition through suppression of Chk1 phosphorylation in human pancreatic cancer cells. Oncol Rep 2017; 38:3238-3244. [PMID: 29048622 DOI: 10.3892/or.2017.5974] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 07/17/2017] [Indexed: 12/17/2022] Open
Abstract
Although gemcitabine (GEM) is frequently used in the treatment of pancreatic cancer, the effects are limited. To increase the inhibitory effect of GEM, the identification of a molecular target is needed. Recent studies have revealed that doublecortin-like kinase 1 (Dclk1) positively regulates tumor growth, invasion, metastasis, factors related to epithelial-mesenchymal transition (EMT), pluripotency, angiogenesis, and anti-apoptosis in pancreatic cancer cells. Therefore, Dclk1 is a potential therapeutic target for pancreatic cancer. However, the Dclk1-signaling pathway including its substrate proteins remains to be elucidated. To identify the candidate substrate proteins phosphorylated by Dclk1, we performed a cancer-related phosphorylated protein microarray using Dclk1-inhibited MIA Paca2 cells. Expression levels of phosphorylated cdc25A (p-cdc25A) and phosphorylated Chk1 (p-Chk1), belonging to the ATR pathway, were decreased by treatment with Dclk1 inhibitor LRRK2-IN-1 (LRRK), indicating Dclk1 involvement in the ATR pathway. Consistent with this finding, the GEM-induced p-Chk1 expression was significantly decreased by treatment with LRRK. Notably, combined treatment with GEM and LRRK allowed cell cycle progression without arresting at S phase, while individual treatment with GEM induced cell cycle arrest at S phase. In addition, combined treatment with GEM and LRRK increased the number of γ-H2AX-positive cells compared with that upon individual treatments. Moreover, LRRK alone, and combined treatment with GEM and LRRK, induced caspase-3 activation and PARP1 cleavage, in contrast to treatment with GEM alone. Finally, combined treatment with GEM and LRRK significantly reduced cell survival compared to individual treatment with GEM. These results indicate that Dclk1 inhibition in combination with GEM treatment offers a novel approach to treat pancreatic cancer cells.
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Affiliation(s)
- Daichi Kawamura
- Department of Surgery and Clinical Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Yoshihiro Takemoto
- Department of Surgery and Clinical Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Arata Nishimoto
- Department of Medical Education, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Koji Ueno
- Department of Surgery and Clinical Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Tohru Hosoyama
- Department of Surgery and Clinical Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Bungo Shirasawa
- Department of Medical Education, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Toshiki Tanaka
- Department of Surgery and Clinical Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Naruji Kugimiya
- Department of Surgery and Clinical Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Eijiro Harada
- Department of Surgery and Clinical Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
| | - Kimikazu Hamano
- Department of Surgery and Clinical Sciences, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
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16
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Goss KL, Koppenhafer SL, Harmoney KM, Terry WW, Gordon DJ. Inhibition of CHK1 sensitizes Ewing sarcoma cells to the ribonucleotide reductase inhibitor gemcitabine. Oncotarget 2017; 8:87016-87032. [PMID: 29152060 PMCID: PMC5675612 DOI: 10.18632/oncotarget.18776] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/22/2017] [Indexed: 12/22/2022] Open
Abstract
Ewing sarcoma is a bone and soft tissue sarcoma that occurs in children and young adults. The EWS-FLI1 gene fusion is the driver mutation in most Ewing sarcoma tumors and functions, in part, as an aberrant transcription factor. We recently identified that Ewing sarcoma cells are sensitive to inhibition of ribonucleotide reductase (RNR), which catalyzes the formation of deoxyribonucleotides from ribonucleotides. In this report, we show that Ewing sarcoma cells are sensitive to treatment with clofarabine, which is a nucleoside analogue and allosteric inhibitor of RNR. However, clofarabine is a reversible inhibitor of RNR and we found that the effect of clofarabine is limited when using a short (6-hour) drug treatment. Gemcitabine, on the other hand, is an irreversible inhibitor of the RRM1 subunit of RNR and this drug induces apoptosis in Ewing sarcoma cells when used in both 6-hour and longer drug treatments. Treatment of Ewing sarcoma cells with gemcitabine also results in activation of checkpoint kinase 1 (CHK1), which is a critical mediator of cell survival in the setting of impaired DNA replication. Notably, inhibition of CHK1 function in Ewing sarcoma cells using a small-molecule CHK1 inhibitor, or siRNA knockdown, in combination with gemcitabine results in increased toxicity both in vitro and in vivo in a mouse xenograft experiment. Overall, our results provide insight into Ewing sarcoma biology and identify a candidate therapeutic target, and drug combination, in Ewing sarcoma.
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Affiliation(s)
- Kelli L Goss
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Iowa, Iowa City, Iowa 52242, USA
| | - Stacia L Koppenhafer
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Iowa, Iowa City, Iowa 52242, USA
| | - Kathryn M Harmoney
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Iowa, Iowa City, Iowa 52242, USA
| | - William W Terry
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Iowa, Iowa City, Iowa 52242, USA
| | - David J Gordon
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Iowa, Iowa City, Iowa 52242, USA
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17
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Yang SH, Kuo TC, Wu H, Guo JC, Hsu C, Hsu CH, Tien YW, Yeh KH, Cheng AL, Kuo SH. Perspectives on the combination of radiotherapy and targeted therapy with DNA repair inhibitors in the treatment of pancreatic cancer. World J Gastroenterol 2016; 22:7275-7288. [PMID: 27621574 PMCID: PMC4997635 DOI: 10.3748/wjg.v22.i32.7275] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 06/20/2016] [Accepted: 07/21/2016] [Indexed: 02/06/2023] Open
Abstract
Pancreatic cancer is highly lethal. Current research that combines radiation with targeted therapy may dramatically improve prognosis. Cancerous cells are characterized by unstable genomes and activation of DNA repair pathways, which are indicated by increased phosphorylation of numerous factors, including H2AX, ATM, ATR, Chk1, Chk2, DNA-PKcs, Rad51, and Ku70/Ku80 heterodimers. Radiotherapy causes DNA damage. Cancer cells can be made more sensitive to the effects of radiation (radiosensitization) through inhibition of DNA repair pathways. The synergistic effects, of two or more combined non-lethal treatments, led to co-administration of chemotherapy and radiosensitization in BRCA-defective cells and patients, with promising results. ATM/Chk2 and ATR/Chk1 pathways are principal regulators of cell cycle arrest, following DNA double-strand or single-strand breaks. DNA double-stranded breaks activate DNA-dependent protein kinase, catalytic subunit (DNA-PKcs). It forms a holoenzyme with Ku70/Ku80 heterodimers, called DNA-PK, which catalyzes the joining of nonhomologous ends. This is the primary repair pathway utilized in human cells after exposure to ionizing radiation. Radiosensitization, induced by inhibitors of ATM, ATR, Chk1, Chk2, Wee1, PP2A, or DNA-PK, has been demonstrated in preclinical pancreatic cancer studies. Clinical trials are underway. Development of agents that inhibit DNA repair pathways to be clinically used in combination with radiotherapy is warranted for the treatment of pancreatic cancer.
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