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Kisielewska M, Filipski M, Sebastianka K, Karaś D, Molik K, Choromańska A. Investigation into the Neuroprotective and Therapeutic Potential of Plant-Derived Chk2 Inhibitors. Int J Mol Sci 2024; 25:7725. [PMID: 39062967 PMCID: PMC11277127 DOI: 10.3390/ijms25147725] [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: 05/19/2024] [Revised: 07/09/2024] [Accepted: 07/11/2024] [Indexed: 07/28/2024] Open
Abstract
Nature provides us with a rich source of compounds with a wide range of applications, including the creation of innovative drugs. Despite advancements in chemically synthesized therapeutics, natural compounds are increasingly significant, especially in cancer treatment, a leading cause of death globally. One promising approach involves the use of natural inhibitors of checkpoint kinase 2 (Chk2), a critical regulator of DNA repair, cell cycle arrest, and apoptosis. Chk2's activation in response to DNA damage can lead to apoptosis or DNA repair, influencing glycolysis and mitochondrial function. In cancer therapy, inhibiting Chk2 can disrupt DNA repair and cell cycle progression, promoting cancer cell death and enhancing the efficacy of radiotherapy and chemotherapy. Additionally, Chk2 inhibitors can safeguard non-cancerous cells during these treatments by inhibiting p53-dependent apoptosis. Beyond oncology, Chk2 inhibition shows potential in treating hepatitis C virus (HCV) infections, as the virus relies on Chk2 for RNA replication in neurodegenerative diseases like amyotrophic lateral sclerosis (ALS), in which DNA damage plays a crucial role. Plant-derived Chk2 inhibitors, such as artemetin, rhamnetin, and curcumin, offer a promising future for treating various diseases with potentially milder side effects and broader metabolic impacts compared to conventional therapies. The review aims to underscore the immense potential of natural Chk2 inhibitors in various therapeutic contexts, particularly in oncology and the treatment of other diseases involving DNA damage and repair mechanisms. These natural Chk2 inhibitors hold significant promise for revolutionizing the landscape of cancer treatment and other diseases. Further research into these compounds could lead to the development of innovative therapies that offer hope for the future with fewer side effects and enhanced efficacy.
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Affiliation(s)
- Monika Kisielewska
- Faculty of Medicine, Wroclaw Medical University, Mikulicza-Radeckiego 5, 50-345 Wroclaw, Poland; (M.K.); (M.F.); (K.S.); (D.K.); (K.M.)
| | - Michał Filipski
- Faculty of Medicine, Wroclaw Medical University, Mikulicza-Radeckiego 5, 50-345 Wroclaw, Poland; (M.K.); (M.F.); (K.S.); (D.K.); (K.M.)
| | - Kamil Sebastianka
- Faculty of Medicine, Wroclaw Medical University, Mikulicza-Radeckiego 5, 50-345 Wroclaw, Poland; (M.K.); (M.F.); (K.S.); (D.K.); (K.M.)
| | - Dobrawa Karaś
- Faculty of Medicine, Wroclaw Medical University, Mikulicza-Radeckiego 5, 50-345 Wroclaw, Poland; (M.K.); (M.F.); (K.S.); (D.K.); (K.M.)
| | - Klaudia Molik
- Faculty of Medicine, Wroclaw Medical University, Mikulicza-Radeckiego 5, 50-345 Wroclaw, Poland; (M.K.); (M.F.); (K.S.); (D.K.); (K.M.)
| | - Anna Choromańska
- Department of Molecular and Cellular Biology, Faculty of Pharmacy, Wroclaw Medical University, Borowska 211A, 50-556 Wroclaw, Poland
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Li Y, Wang X, Hou X, Ma X. Could Inhibiting the DNA Damage Repair Checkpoint Rescue Immune-Checkpoint-Inhibitor-Resistant Endometrial Cancer? J Clin Med 2023; 12:jcm12083014. [PMID: 37109350 PMCID: PMC10144486 DOI: 10.3390/jcm12083014] [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: 02/17/2023] [Revised: 03/23/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
Endometrial cancer (EC) is increasingly undermining female health worldwide, with poor survival rates for advanced or recurrent/metastatic diseases. The application of immune checkpoint inhibitors (ICIs) has opened a window of opportunity for patients with first-line therapy failure. However, there is a subset of patients with endometrial cancer who remain insensitive to immunotherapy alone. Therefore, it is necessary to develop new therapeutic agents and further explore reliable combinational strategies to optimize the efficacy of immunotherapy. DNA damage repair (DDR) inhibitors as novel targeted drugs are able to generate genomic toxicity and induce cell death in solid tumors, including EC. Recently, growing evidence has demonstrated the DDR pathway modulates innate and adaptive immunity in tumors. In this review, we concentrate on the exploration of the intrinsic correlation between DDR pathways, especially the ATM-CHK2-P53 pathway and the ATR-CHK1-WEE1 pathway, and oncologic immune response, as well as the feasibility of adding DDR inhibitors to ICIs for the treatment of patients with advanced or recurrent/metastatic EC. We hope that this review will offer some beneficial references to the investigation of immunotherapy and provide a reasonable basis for "double-checkpoint inhibition" in EC.
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Affiliation(s)
- Yinuo Li
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xiangyu Wang
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xin Hou
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xiangyi Ma
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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3
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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: 7] [Impact Index Per Article: 7.0] [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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4
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Evolving DNA repair synthetic lethality targets in cancer. Biosci Rep 2022; 42:232162. [PMID: 36420962 PMCID: PMC9760629 DOI: 10.1042/bsr20221713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/21/2022] [Accepted: 11/24/2022] [Indexed: 11/25/2022] Open
Abstract
DNA damage signaling response and repair (DDR) is a critical defense mechanism against genomic instability. Impaired DNA repair capacity is an important risk factor for cancer development. On the other hand, up-regulation of DDR mechanisms is a feature of cancer chemotherapy and radiotherapy resistance. Advances in our understanding of DDR and its complex role in cancer has led to several translational DNA repair-targeted investigations culminating in clinically viable precision oncology strategy using poly(ADP-ribose) polymerase (PARP) inhibitors in breast, ovarian, pancreatic, and prostate cancers. While PARP directed synthetic lethality has improved outcomes for many patients, the lack of sustained clinical response and the development of resistance pose significant clinical challenges. Therefore, the search for additional DDR-directed drug targets and novel synthetic lethality approaches is highly desirable and is an area of intense preclinical and clinical investigation. Here, we provide an overview of the mammalian DNA repair pathways and then focus on current state of PARP inhibitors (PARPi) and other emerging DNA repair inhibitors for synthetic lethality in cancer.
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5
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Tsoi H, Tsang WC, Man EPS, Leung MH, You CP, Chan SY, Chan WL, Khoo US. Checkpoint Kinase 2 Inhibition Can Reverse Tamoxifen Resistance in ER-Positive Breast Cancer. Int J Mol Sci 2022; 23:ijms232012290. [PMID: 36293165 PMCID: PMC9604393 DOI: 10.3390/ijms232012290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/11/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022] Open
Abstract
Breast cancer is a heterogeneous disease. Tamoxifen is frequently used to treat ER-positive breast cancer. Our team has identified a novel splice variant of NCOR2, BQ323636.1 (BQ), that mediates tamoxifen resistance. However, the upstream factors that modulate BQ expression are not apparent. This study reveals that tamoxifen treatment causes induction of DNA damage which can enhance BQ expression. We show that DNA damage can activate the ATM/CHK2 and ATR/CHK1 signalling cascades and confirm that ATM/CHK2 signalling is responsible for enhancing the protein stability of BQ. siRNA or a small inhibitor targeting CHK2 resulted in the reduction in BQ expression through reduced phosphorylation and enhanced poly-ubiquitination of BQ. Inhibition of CHK2 by CCT241533 could reverse tamoxifen resistance in vitro and in vivo. Using clinical samples in the tissue microarray, we confirmed that high p-CHK2 expression was significantly associated with high nuclear BQ expression, tamoxifen resistance and poorer overall and disease-specific survival. In conclusion, tamoxifen treatment can enhance BQ expression in ER-positive breast cancer by activating the ATM/CHK2 axis. Targeting CHK2 is a promising approach to overcoming tamoxifen resistance in ER-positive breast cancer.
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Affiliation(s)
- Ho Tsoi
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Wai-Chung Tsang
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Ellen P. S. Man
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Man-Hong Leung
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Chan-Ping You
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Sum-Yin Chan
- Department of Clinical Oncology, Queen Mary Hospital, Hong Kong SAR, China
| | - Wing-Lok Chan
- Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Ui-Soon Khoo
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Correspondence: ; Tel.: +852-2255-2664; Fax: +852-2218-5205
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6
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Maleki Dana P, Sadoughi F, Mirzaei H, Asemi Z, Yousefi B. DNA damage response and repair in the development and treatment of brain tumors. Eur J Pharmacol 2022; 924:174957. [DOI: 10.1016/j.ejphar.2022.174957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 04/03/2022] [Accepted: 04/11/2022] [Indexed: 11/03/2022]
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7
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Xie B, Luo A. Nucleic Acid Sensing Pathways in DNA Repair Targeted Cancer Therapy. Front Cell Dev Biol 2022; 10:903781. [PMID: 35557952 PMCID: PMC9089908 DOI: 10.3389/fcell.2022.903781] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 04/08/2022] [Indexed: 12/24/2022] Open
Abstract
The repair of DNA damage is a complex process, which helps to maintain genome fidelity, and the ability of cancer cells to repair therapeutically DNA damage induced by clinical treatments will affect the therapeutic efficacy. In the past decade, great success has been achieved by targeting the DNA repair network in tumors. Recent studies suggest that DNA damage impacts cellular innate and adaptive immune responses through nucleic acid-sensing pathways, which play essential roles in the efficacy of DNA repair targeted therapy. In this review, we summarize the current understanding of the molecular mechanism of innate immune response triggered by DNA damage through nucleic acid-sensing pathways, including DNA sensing via the cyclic GMP-AMP synthase (cGAS), Toll-like receptor 9 (TLR9), absent in melanoma 2 (AIM2), DNA-dependent protein kinase (DNA-PK), and Mre11-Rad50-Nbs1 complex (MRN) complex, and RNA sensing via the TLR3/7/8 and retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs). Furthermore, we will focus on the recent developments in the impacts of nucleic acid-sensing pathways on the DNA damage response (DDR). Elucidating the DDR-immune response interplay will be critical to harness immunomodulatory effects to improve the efficacy of antitumor immunity therapeutic strategies and build future therapeutic approaches.
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Affiliation(s)
- Bingteng Xie
- School of Life Science, Beijing Institute of Technology, Beijing, China.,Key Laboratory of Molecular Medicine and Biological Diagnosis and Treatment, Beijing Institute of Technology, Ministry of Industry and Information Technology, Beijing, China
| | - Aiqin Luo
- School of Life Science, Beijing Institute of Technology, Beijing, China.,Key Laboratory of Molecular Medicine and Biological Diagnosis and Treatment, Beijing Institute of Technology, Ministry of Industry and Information Technology, Beijing, China
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8
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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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Russi M, Marson D, Fermeglia A, Aulic S, Fermeglia M, Laurini E, Pricl S. The fellowship of the RING: BRCA1, its partner BARD1 and their liaison in DNA repair and cancer. Pharmacol Ther 2021; 232:108009. [PMID: 34619284 DOI: 10.1016/j.pharmthera.2021.108009] [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: 08/14/2021] [Revised: 08/22/2021] [Accepted: 09/20/2021] [Indexed: 12/12/2022]
Abstract
The breast cancer type 1 susceptibility protein (BRCA1) and its partner - the BRCA1-associated RING domain protein 1 (BARD1) - are key players in a plethora of fundamental biological functions including, among others, DNA repair, replication fork protection, cell cycle progression, telomere maintenance, chromatin remodeling, apoptosis and tumor suppression. However, mutations in their encoding genes transform them into dangerous threats, and substantially increase the risk of developing cancer and other malignancies during the lifetime of the affected individuals. Understanding how BRCA1 and BARD1 perform their biological activities therefore not only provides a powerful mean to prevent such fatal occurrences but can also pave the way to the development of new targeted therapeutics. Thus, through this review work we aim at presenting the major efforts focused on the functional characterization and structural insights of BRCA1 and BARD1, per se and in combination with all their principal mediators and regulators, and on the multifaceted roles these proteins play in the maintenance of human genome integrity.
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Affiliation(s)
- Maria Russi
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Domenico Marson
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Alice Fermeglia
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Suzana Aulic
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Maurizio Fermeglia
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Erik Laurini
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Sabrina Pricl
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy; Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland.
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10
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Checker R, Patwardhan RS, Jayakumar S, Maurya DK, Bandekar M, Sharma D, Sandur SK. Chemical and biological basis for development of novel radioprotective drugs for cancer therapy. Free Radic Res 2021; 55:595-625. [PMID: 34181503 DOI: 10.1080/10715762.2021.1876854] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Ionizing radiation (IR) causes chemical changes in biological systems through direct interaction with the macromolecules or by causing radiolysis of water. This property of IR is harnessed in the clinic for radiotherapy in almost 50% of cancers patients. Despite the advent of stereotactic radiotherapy instruments and other advancements in shielding techniques, the inadvertent deposition of radiation dose in the surrounding normal tissue can cause late effects of radiation injury in normal tissues. Radioprotectors, which are chemical or biological agents, can reduce or mitigate these toxic side-effects of radiotherapy in cancer patients and also during radiation accidents. The desired characteristics of an ideal radioprotector include low chemical toxicity, high risk to benefit ratio and specific protection of normal cells against the harmful effects of radiation without compromising the cytotoxic effects of IR on cancer cells. Since reactive oxygen species (ROS) are the major contributors of IR mediated toxicity, plethora of studies have highlighted the potential role of antioxidants to protect against IR induced damage. However, owing to the lack of any clinically approved radioprotector against whole body radiation, researchers have shifted the focus toward finding alternate targets that could be exploited for the development of novel agents. The present review provides a comprehensive insight in to the different strategies, encompassing prime molecular targets, which have been employed to develop radiation protectors/countermeasures. It is anticipated that understanding such factors will lead to the development of novel strategies for increasing the outcome of radiotherapy by minimizing normal tissue toxicity.
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Affiliation(s)
- Rahul Checker
- Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai, India.,Homi Bhabha National Institute, Anushaktinagar, Mumbai, India
| | - Raghavendra S Patwardhan
- Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai, India.,Homi Bhabha National Institute, Anushaktinagar, Mumbai, India
| | - Sundarraj Jayakumar
- Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai, India
| | - Dharmendra Kumar Maurya
- Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai, India.,Homi Bhabha National Institute, Anushaktinagar, Mumbai, India
| | - Mayuri Bandekar
- Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai, India
| | - Deepak Sharma
- Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai, India.,Homi Bhabha National Institute, Anushaktinagar, Mumbai, India
| | - Santosh K Sandur
- Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai, India.,Homi Bhabha National Institute, Anushaktinagar, Mumbai, India
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11
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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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12
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Xu D, Li C. Regulation of the SIAH2-HIF-1 Axis by Protein Kinases and Its Implication in Cancer Therapy. Front Cell Dev Biol 2021; 9:646687. [PMID: 33842469 PMCID: PMC8027324 DOI: 10.3389/fcell.2021.646687] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 03/08/2021] [Indexed: 12/16/2022] Open
Abstract
The cellular response to hypoxia is a key biological process that facilitates adaptation of cells to oxygen deprivation (hypoxia). This process is critical for cancer cells to adapt to the hypoxic tumor microenvironment resulting from rapid tumor growth. Hypoxia-inducible factor 1 (HIF-1) is a transcription factor and a master regulator of the cellular response to hypoxia. The activity of HIF-1 is dictated primarily by its alpha subunit (HIF-1α), whose level and/or activity are largely regulated by an oxygen-dependent and ubiquitin/proteasome-mediated process. Prolyl hydroxylases (PHDs) and the E3 ubiquitin ligase Von Hippel-Lindau factor (VHL) catalyze hydroxylation and subsequent ubiquitin-dependent degradation of HIF-1α by the proteasome. Seven in Absentia Homolog 2 (SIAH2), a RING finger-containing E3 ubiquitin ligase, stabilizes HIF-1α by targeting PHDs for ubiquitin-mediated degradation by the proteasome. This SIAH2-HIF-1 signaling axis is important for maintaining the level of HIF-1α under both normoxic and hypoxic conditions. A number of protein kinases have been shown to phosphorylate SIAH2, thereby regulating its stability, activity, or substrate binding. In this review, we will discuss the regulation of the SIAH2-HIF-1 axis via phosphorylation of SIAH2 by these kinases and the potential implication of this regulation in cancer biology and cancer therapy.
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Affiliation(s)
- Dazhong Xu
- Department of Pathology, Microbiology and Immunology, School of Medicine, New York Medical College, Valhalla, NY, United States
| | - Cen Li
- Department of Pathology, Microbiology and Immunology, School of Medicine, New York Medical College, Valhalla, NY, United States
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13
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Katoch A, Nayak D, Faheem MM, Kumar A, Sahu PK, Gupta AP, Kumar LD, Goswami A. Natural podophyllotoxin analog 4DPG attenuates EMT and colorectal cancer progression via activation of checkpoint kinase 2. Cell Death Discov 2021; 7:25. [PMID: 33500399 PMCID: PMC7838189 DOI: 10.1038/s41420-021-00405-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 10/17/2020] [Accepted: 11/13/2020] [Indexed: 02/07/2023] Open
Abstract
Epithelial–mesenchymal transition (EMT) is critical for the metastatic dissemination of cancer cells and contributes to drug resistance. In this study, we observed that epithelial colorectal cancer (CRC) cells transiently exposed to 5-fluorouracil (5-FU) (a chemotherapeutic drug for CRC) as well as 5-FU-resistant cells (5-FU-R) develop EMT characters as evidenced by activation of Vimentin and augmented invasive properties. On the other hand, 4DPG (4′-demethyl-deoxypodophyllotoxin glucoside), a natural podophyllotoxin analog attenuates EMT and invadopodia formation abilities of HCT-116/5-FU-R and SW-620/5-FU-R cells. Treatment with 4DPG restrains Vimentin phosphorylation (Ser38) in 5-FU-R cells, along with downregulation of mesenchymal markers Twist1 and MMP-2 while augmenting the expression of epithelial markers E-cadherin and TIMP-1. Moreover, 4DPG boosts the tumor-suppressor protein, checkpoint kinase 2 (Chk2) via phosphorylation at Thr68 in a dose-dependent manner in 5-FU-R cells. Mechanistically, SiRNA-mediated silencing of Chk2, as well as treatment with Chk2-specific small-molecule inhibitor (PV1019), divulges that 4DPG represses Vimentin activation in a Chk2-dependent manner. Furthermore, immunoprecipitation analysis unveiled that 4DPG prevents complex formation between Vimentin and p53 resulting in the rescue of p53 and its nuclear localization in aggressive 5-FU-R cells. In addition, 4DPG confers suitable pharmacokinetic properties and strongly abrogates tumor growth, polyps formation, and lung metastasis in an orthotopic rat colorectal carcinoma model. In conclusion, our findings demonstrate 4DPG as a targeted antitumor/anti-metastatic pharmacological lead compound to circumvent EMT-associated drug resistance and suggest its clinical benefits for the treatment of aggressive cancers.
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Affiliation(s)
- Archana Katoch
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, 201002, India.,Cancer Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, Jammu and Kashmir, 180001, India
| | - Debasis Nayak
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Mir Mohd Faheem
- Cancer Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, Jammu and Kashmir, 180001, India.,School of Biotechnology, University of Jammu, Jammu, Jammu and Kashmir, 180006, India
| | - Aviral Kumar
- Cancer Biology, CSIR-Centre for Cellular & Molecular Biology, Hyderabad, Telangana, 500007, India
| | - Promod Kumar Sahu
- Cancer Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, Jammu and Kashmir, 180001, India
| | - Ajai Prakash Gupta
- Quality Control and Quality Assurance Division, CSIR-Indian Institute of Integrative Medicine, Jammu, Jammu and Kashmir, 180001, India
| | - Lekha Dinesh Kumar
- Cancer Biology, CSIR-Centre for Cellular & Molecular Biology, Hyderabad, Telangana, 500007, India
| | - Anindya Goswami
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, 201002, India. .,Cancer Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, Jammu and Kashmir, 180001, India.
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14
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Majd NK, Yap TA, Koul D, Balasubramaniyan V, Li X, Khan S, Gandy KS, Yung WKA, de Groot JF. The promise of DNA damage response inhibitors for the treatment of glioblastoma. Neurooncol Adv 2021; 3:vdab015. [PMID: 33738447 PMCID: PMC7954093 DOI: 10.1093/noajnl/vdab015] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Glioblastoma (GBM), the most aggressive primary brain tumor, has a dismal prognosis. Despite our growing knowledge of genomic and epigenomic alterations in GBM, standard therapies and outcomes have not changed significantly in the past two decades. There is therefore an urgent unmet need to develop novel therapies for GBM. The inter- and intratumoral heterogeneity of GBM, inadequate drug concentrations in the tumor owing to the blood-brain barrier, redundant signaling pathways contributing to resistance to conventional therapies, and an immunosuppressive tumor microenvironment, have all hindered the development of novel therapies for GBM. Given the high frequency of DNA damage pathway alterations in GBM, researchers have focused their efforts on pharmacologically targeting key enzymes, including poly(ADP-ribose) polymerase (PARP), DNA-dependent protein kinase, ataxia telangiectasia-mutated, and ataxia telangiectasia and Rad3-related. The mainstays of GBM treatment, ionizing radiation and alkylating chemotherapy, generate DNA damage that is repaired through the upregulation and activation of DNA damage response (DDR) enzymes. Therefore, the use of PARP and other DDR inhibitors to render GBM cells more vulnerable to conventional treatments is an area of intense investigation. In this review, we highlight the growing body of data behind DDR inhibitors in GBM, with a focus on putative predictive biomarkers of response. We also discuss the challenges involved in the successful development of DDR inhibitors for GBM, including the intracranial location and predicted overlapping toxicities of DDR agents with current standards of care, and propose promising strategies to overcome these hurdles.
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Affiliation(s)
- Nazanin K Majd
- Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Timothy A Yap
- Department of Investigational Cancer Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Dimpy Koul
- Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | | | - Xiaolong Li
- Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Sabbir Khan
- Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Katilin S Gandy
- Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - W K Alfred Yung
- Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - John F de Groot
- Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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15
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Lynch WE, Whitlock CR, Padgett CW. Ethyl 1 H-indole-2-carboxyl-ate. IUCRDATA 2020; 5:x201205. [PMID: 36338908 PMCID: PMC9462284 DOI: 10.1107/s2414314620012055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 08/31/2020] [Indexed: 11/25/2022] Open
Abstract
Our work in the area of synthesis of tris indole compounds as a potential chelator led to the synthesis and crystallization of ethyl 1H-indole-2-carboxyl-ate, C11H11NO2, an indole that was synthesized by the thionyl chloride reaction of 1H-indole-2-carb-oxy-lic acid, followed by dissolution in ethanol. The mol-ecular packing exhibits a herringbone pattern with the zigzag running along the b-axis direction; the compound crystallizes as a hydrogen-bonded dimer resulting from O⋯H-N hydrogen bonds, between the indole N-H group and the keto oxygen atom, which build centrosymmetric R 2 2(10) ring motifs in the crystal.
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Affiliation(s)
- Will E. Lynch
- Georgia Southern University, Department of Chemistry and Biochemistry, Box 8064, Statesboro, GA 30460, USA
| | - Christine R. Whitlock
- Georgia Southern University, Department of Chemistry and Biochemistry, Box 8064, Statesboro, GA 30460, USA
| | - Clifford W. Padgett
- Georgia Southern University, Department of Chemistry and Biochemistry, Box 8064, Statesboro, GA 30460, USA
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16
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Ferri A, Stagni V, Barilà D. Targeting the DNA Damage Response to Overcome Cancer Drug Resistance in Glioblastoma. Int J Mol Sci 2020; 21:E4910. [PMID: 32664581 PMCID: PMC7402284 DOI: 10.3390/ijms21144910] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/07/2020] [Accepted: 07/09/2020] [Indexed: 12/16/2022] Open
Abstract
Glioblastoma multiforme (GBM) is a severe brain tumor whose ability to mutate and adapt to therapies is at the base for the extremely poor survival rate of patients. Despite multiple efforts to develop alternative forms of treatment, advances have been disappointing and GBM remains an arduous tumor to treat. One of the leading causes for its strong resistance is the innate upregulation of DNA repair mechanisms. Since standard therapy consists of a combinatory use of ionizing radiation and alkylating drugs, which both damage DNA, targeting the DNA damage response (DDR) is proving to be a beneficial strategy to sensitize tumor cells to treatment. In this review, we will discuss how recent progress in the availability of the DDR kinase inhibitors will be key for future therapy development. Further, we will examine the principal existing DDR inhibitors, with special focus on those currently in use for GBM clinical trials.
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Affiliation(s)
- Alessandra Ferri
- Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy;
- Laboratory of Signal Transduction, IRCCS-Fondazione Santa Lucia, 00179 Rome, Italy;
| | - Venturina Stagni
- Laboratory of Signal Transduction, IRCCS-Fondazione Santa Lucia, 00179 Rome, Italy;
- Institute of Molecular Biology and Pathology, National Research Council (CNR), 00185 Rome, Italy
| | - Daniela Barilà
- Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy;
- Laboratory of Signal Transduction, IRCCS-Fondazione Santa Lucia, 00179 Rome, Italy;
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17
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Abstract
DNA damage response (DDR) pathway prevents high level endogenous and environmental DNA damage being replicated and passed on to the next generation of cells via an orchestrated and integrated network of cell cycle checkpoint signalling and DNA repair pathways. Depending on the type of damage, and where in the cell cycle it occurs different pathways are involved, with the ATM-CHK2-p53 pathway controlling the G1 checkpoint or ATR-CHK1-Wee1 pathway controlling the S and G2/M checkpoints. Loss of G1 checkpoint control is common in cancer through TP53, ATM mutations, Rb loss or cyclin E overexpression, providing a stronger rationale for targeting the S/G2 checkpoints. This review will focus on the ATM-CHK2-p53-p21 pathway and the ATR-CHK1-WEE1 pathway and ongoing efforts to target these pathways for patient benefit.
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18
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Bauzá A, Frontera A, Mooibroek TJ. π-Hole Interactions Involving Nitro Aromatic Ligands in Protein Structures. Chemistry 2019; 25:13436-13443. [PMID: 31453653 PMCID: PMC6856858 DOI: 10.1002/chem.201903404] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Indexed: 01/03/2023]
Abstract
Studying noncanonical intermolecular interactions between a ligand and a protein constitutes an emerging research field. Identifying synthetically accessible molecular fragments that can engage in intermolecular interactions is a key objective in this area. Here, it is shown that so-called "π-hole interactions" are present between the nitro moiety in nitro aromatic ligands and lone pairs within protein structures (water and protein carbonyls and sulfurs). Ample structural evidence was found in a PDB analysis and computations reveal interaction energies of about -5 kcal mol-1 for ligand-protein π-hole interactions. Several examples are highlighted for which a π-hole interaction is implicated in the superior binding affinity or inhibition of a nitro aromatic ligand versus a similar non-nitro analogue. The discovery that π-hole interactions with nitro aromatics are significant within protein structures parallels the finding that halogen bonds are biologically relevant. This has implications for the interpretation of ligand-protein complexation phenomena, for example, involving the more than 50 approved drugs that contain a nitro aromatic moiety.
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Affiliation(s)
- Antonio Bauzá
- Department of ChemistryUniversitat de les Illes BalearsCrta. de Valldemossa km 7.507122Palma (Baleares)Spain
| | - Antonio Frontera
- Department of ChemistryUniversitat de les Illes BalearsCrta. de Valldemossa km 7.507122Palma (Baleares)Spain
| | - Tiddo Jonathan Mooibroek
- van ‘t Hoff Institute for Molecular SciencesUniversiteit van AmsterdamScience Park 9041098XHAmsterdamThe Netherlands
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19
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Karunakaran J, Dhatchana Moorthy N, Chowdhury SR, Iqbal S, Majumder HK, Gunasekaran K, Vellaichamy E, Mohanakrishnan AK. Divergent Synthesis and Evaluation of the in vitro Cytotoxicity Profiles of 3,4-Ethylenedioxythiophenyl-2-propen-1-one Analogues. ChemMedChem 2019; 14:1418-1430. [PMID: 31343838 DOI: 10.1002/cmdc.201900225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/08/2019] [Indexed: 12/18/2022]
Abstract
A new series of 3,4-ethylenedioxythiophene (EDOT)-appended propenones were prepared by condensation reaction and their in vitro cytotoxicity effects were evaluated against five human cancer cell lines. Preliminary structure-activity relationships of EDOT-incorporated 2-propenone derivatives were also established. The EDOT-appended enones demonstrated significant cytotoxicity against human cancer cell lines. The most active analogue, (E)-3-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (3 p, GI50 =110 nm), severely inhibited the clonogenic potential of cancer cells, and induced cell-cycle arrest in the G2/M phase and caused an accumulation of HCT116 colon cancer cells with >4 N DNA content. Also, 3 p exhibited weak inhibition of the enzymatic activity of human topoisomerase I. Molecular docking studies indicated preferential binding of the compounds to the ATP-binding pocket of the human checkpoint 2 kinase (Chk2) catalytic domain, thus, identifying a novel diaryl 2-propenone chemotype for the development of potent inhibitors of Chk2.
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Affiliation(s)
- Jayachandran Karunakaran
- Department of Organic Chemistry, School of Chemistry, University of Madras, Guindy Campus, Chennai, 600025, Tamil Nadu, India
| | - Nachiappan Dhatchana Moorthy
- Department of Biochemistry, University of Madras, Guindy Campus, Chennai, 600025, Tamil Nadu, India.,Department of Biotechnology, Orchid Pharma Limited, Orchid Towers #313, Valluvar Kottam High Road, Nungambakkam, Chennai, 600034, Tamil Nadu, India
| | - Somenath Roy Chowdhury
- Division of Infectious Diseases & Immunology, Indian Institute of Chemical Biology, 4, Raja S. C. Mallick Road, Jadavpur, Kolkata, 700032, West Bengal, India
| | - Saleem Iqbal
- Center for Advanced studies in Crystallography & Biophysics, University of Madras, Guindy Campus, Chennai, 600025, Tamil Nadu, India
| | - Hemanta K Majumder
- Division of Infectious Diseases & Immunology, Indian Institute of Chemical Biology, 4, Raja S. C. Mallick Road, Jadavpur, Kolkata, 700032, West Bengal, India
| | - Krishnasamy Gunasekaran
- Center for Advanced studies in Crystallography & Biophysics, University of Madras, Guindy Campus, Chennai, 600025, Tamil Nadu, India
| | - Elangovan Vellaichamy
- Department of Biochemistry, University of Madras, Guindy Campus, Chennai, 600025, Tamil Nadu, India
| | - Arasambattu K Mohanakrishnan
- Department of Organic Chemistry, School of Chemistry, University of Madras, Guindy Campus, Chennai, 600025, Tamil Nadu, India
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20
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Bhattacharjee S, Nandi S. Rare Genetic Diseases with Defects in DNA Repair: Opportunities and Challenges in Orphan Drug Development for Targeted Cancer Therapy. Cancers (Basel) 2018; 10:E298. [PMID: 30200453 PMCID: PMC6162646 DOI: 10.3390/cancers10090298] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/27/2018] [Accepted: 08/28/2018] [Indexed: 12/22/2022] Open
Abstract
A better understanding of mechanistic insights into genes and enzymes implicated in rare diseases provide a unique opportunity for orphan drug development. Advances made in identification of synthetic lethal relationships between rare disorder genes with oncogenes and tumor suppressor genes have brought in new anticancer therapeutic opportunities. Additionally, the rapid development of small molecule inhibitors against enzymes that participate in DNA damage response and repair has been a successful strategy for targeted cancer therapeutics. Here, we discuss the recent advances in our understanding of how many rare disease genes participate in promoting genome stability. We also summarize the latest developments in exploiting rare diseases to uncover new biological mechanisms and identify new synthetic lethal interactions for anticancer drug discovery that are in various stages of preclinical and clinical studies.
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Affiliation(s)
| | - Saikat Nandi
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, NY 11724, USA.
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21
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Attenuated DNA damage responses and increased apoptosis characterize human hematopoietic stem cells exposed to irradiation. Sci Rep 2018; 8:6071. [PMID: 29666389 PMCID: PMC5904119 DOI: 10.1038/s41598-018-24440-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 04/03/2018] [Indexed: 12/18/2022] Open
Abstract
Failure to precisely repair DNA damage in self-renewing Hematopoietic Stem and early Progenitor Cells (HSPCs) can disrupt normal hematopoiesis and promote leukemogenesis. Although HSPCs are widely considered a target of ionizing radiation (IR)-induced hematopoietic injury, definitive data regarding cell death, DNA repair, and genomic stability in these rare quiescent cells are scarce. We found that irradiated HSPCs, but not lineage-committed progenitors (CPs), undergo rapid ATM-dependent apoptosis, which is suppressed upon interaction with bone-marrow stroma cells. Using DNA repair reporters to quantify mutagenic Non-Homologous End Joining (NHEJ) processes, we found that HSPCs exhibit reduced NHEJ activities in comparison with CPs. HSPC-stroma interactions did not affect the NHEJ capacity of HSPCs, emphasizing its cell autonomous regulation. We noted diminished expression of multiple double strand break (DSB) repair transcripts along with more persistent 53BP1 foci in irradiated HSPCs in comparison with CPs, which can account for low NHEJ activity and its distinct control in HSPCs. Finally, we documented clonal chromosomal aberrations in 10% of IR-surviving HSPCs. Taken together, our results revealed potential mechanisms contributing to the inherent susceptibility of human HSPC to the cytotoxic and mutagenic effects of DNA damage.
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22
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Yuan Z, Ma J, Meng X, Chen N, Shen M. Chk2 deficiency alleviates irradiation-induced taste dysfunction by inhibiting p53-dependent apoptosis. Oral Dis 2018; 24:856-863. [PMID: 29292572 DOI: 10.1111/odi.12822] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Revised: 12/15/2017] [Accepted: 12/21/2017] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Taste dysfunction is one of the most common complications following radiotherapy, which leads to decreased appetite and life quality of patients suffering from head and neck cancer. The aim of this study was to investigate the role of checkpoint kinase 2 (Chk2) deficiency in irradiation-induced taste dysfunction. MATERIALS AND METHODS Alterations in oxidative stress, DNA damage, and potential signaling pathway were compared between Chk2-deficient (Chk2-/- ) mice and their wild-type (WT) littermates pre-irradiation and 7 and 30 days postirradiation by biochemistry and immunohistochemistry. RESULTS Chk2-/- mice showed less loss of type II and type III taste cells, lower expression of p53, caspase-3, and cleaved caspase-3, and lower apoptosis levels. However, no significant differences in H2 O2 and MDA concentrations, T-SOD and GSH-Px activities, and expression of SOD1, SOD2, and 8-OHdG were detected in the taste buds of Chk2-/- mice as compared to those of WT mice. CONCLUSION Chk2 deficiency downregulated the expression of p53 and inhibited cellular apoptosis, partly contributing to the radioprotective effect on taste cells, but did not alter oxidative stress levels, antioxidant ability, and oxidative DNA damage in taste buds.
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Affiliation(s)
- Zhiyao Yuan
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
| | - Junchi Ma
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
| | - Xin Meng
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
| | - Ning Chen
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China
| | - Ming Shen
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China.,Department of Dental Implant, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
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23
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Galal SA, Khattab M, Shouman SA, Ramadan R, Kandil OM, Kandil OM, Tabll A, El Abd YS, El-Shenawy R, Attia YM, El-Rashedy AA, El Diwani HI. Part III: Novel checkpoint kinase 2 (Chk2) inhibitors; design, synthesis and biological evaluation of pyrimidine-benzimidazole conjugates. Eur J Med Chem 2018; 146:687-708. [PMID: 29407991 DOI: 10.1016/j.ejmech.2018.01.072] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 01/20/2018] [Accepted: 01/22/2018] [Indexed: 02/07/2023]
Abstract
Recently a dramatic development of the cancer drug discovery has been shown in the field of targeted cancer therapy. Checkpoint kinase 2 (Chk2) inhibitors offer a promising approach to enhance the effectiveness of cancer chemotherapy. Accordingly, in this study many pyrimidine-benzimidazole conjugates were designed and twelve feasible derivatives were selected to be synthesized to investigate their activity against Chk2 and subjected to study their antitumor activity alone and in combination with the genotoxic anticancer drugs cisplatin and doxorubicin on breast carcinoma, (ER+) cell line (MCF-7). The results indicated that the studied compounds inhibited Chk2 activity with high potency (IC50 = 5.56 nM - 46.20 nM). The studied candidates exhibited remarkable antitumor activity against MCF-7 (IG50 = 6.6 μM - 24.9 μM). Compounds 10a-c, 14 and 15 significantly potentiated the activity of the studied genotoxic drugs, whereas, compounds 9b and 20-23 antagonized their activity. Moreover, the combination of compound 10b with cisplatin revealed the best apoptotic effect as well as combination of compound 10b with doxorubicin led to complete arrest of the cell cycle at S phase where more than 40% of cells are in the S phase with no cells at G2/M. Structure-activity relationship was discussed on the basis of molecular modeling study using Molecular modeling Environment program (MOE).
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Affiliation(s)
- Shadia A Galal
- Department of Chemistry of Natural and Microbial Products, Division of Pharmaceutical and Drug Industries, National Research Centre, Cairo, 12622, Egypt.
| | - Muhammad Khattab
- Department of Chemistry of Natural and Microbial Products, Division of Pharmaceutical and Drug Industries, National Research Centre, Cairo, 12622, Egypt
| | - Samia A Shouman
- Department of Cancer Biology, National Cancer Institute, Cairo University, Egypt
| | - Raghda Ramadan
- Radiobiology Unit, Belgian Nuclear Research Center (SCK•CEN), Mol, Belgium; Department of Basic Medical Sciences, Physiology Group, Ghent University, Ghent, Belgium
| | - Omaima M Kandil
- Department of Animal Reproduction & Artificial Insemination, Division, of Veterinary Research, National Research Centre, Cairo, 12622, Egypt
| | - Omnia M Kandil
- Department of Parasitology, Animal Disease, Division, of Veterinary, National Research Centre, Cairo, 12622, Egypt
| | - Ashraf Tabll
- Department of Microbial Biotechnology, Division of Genetic Engineering & Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Yasmine S El Abd
- Department of Microbial Biotechnology, Division of Genetic Engineering & Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Reem El-Shenawy
- Department of Microbial Biotechnology, Division of Genetic Engineering & Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Yasmin M Attia
- Department of Cancer Biology, National Cancer Institute, Cairo University, Egypt
| | - Ahmed A El-Rashedy
- Department of Chemistry of Natural and Microbial Products, Division of Pharmaceutical and Drug Industries, National Research Centre, Cairo, 12622, Egypt
| | - Hoda I El Diwani
- Department of Chemistry of Natural and Microbial Products, Division of Pharmaceutical and Drug Industries, National Research Centre, Cairo, 12622, Egypt
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24
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Galal SA, Khairat SHM, Ali HI, Shouman SA, Attia YM, Ali MM, Mahmoud AE, Abdel-Halim AH, Fyiad AA, Tabll A, El-Shenawy R, El Abd YS, Ramdan R, El Diwani HI. Part II: New candidates of pyrazole-benzimidazole conjugates as checkpoint kinase 2 (Chk2) inhibitors. Eur J Med Chem 2018; 144:859-873. [PMID: 29316526 DOI: 10.1016/j.ejmech.2017.12.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Revised: 10/12/2017] [Accepted: 12/06/2017] [Indexed: 02/07/2023]
Abstract
The development of checkpoint kinase 2 (Chk2) inhibitors for the treatment of cancer has been an ongoing and attractive objective in drug discovery. In this study, twenty-one feasible pyrazole-benzimidazole conjugates were synthesized to study their effect against Chk2 activity using Checkpoint Kinase Assay. The antitumor activity of these compounds was investigated using SRB assay. A potentiation effect of the synthesized Chk2 inhibitors was also investigated using the genotoxic anticancer drugs cisplatin and doxorubicin on breast carcinoma, (ER+) cell line (MCF-7). In vivo Chk2 and antitumor activities of 8d as a single-agent, and in combination with doxorubicin, were evaluated in breast cancer bearing animals induced by N-methylnitrosourea. The effect of 8d alone and in combination with doxorubicin was also studied on cell-cycle phases of MCF-7 cells using flow cytometry analysis. The results revealed their potencies as Chk2 inhibitors with IC50 ranges from 9.95 to 65.07 nM. Generally the effect of cisplatin or doxorubicin was potentiated by the effect of most of the compounds that were studied. The in vivo results indicated that the combination of 8d and doxorubicin inhibited checkpoint kinase activity more than either doxorubicin or 8d alone. There was a positive correlation between checkpoint kinase inhibition and the improvement observed in histopathological features. Single dose treatment with doxorubicin or 8d produced S phase cell cycle arrest whereas their combination created cell cycle arrest at G2/M from 8% in case of doxorubicin to 51% in combination. Gold molecular modelling studies displayed a high correlation to the biological results.
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Affiliation(s)
- Shadia A Galal
- Department of Chemistry of Natural and Microbial Products, Division of Pharmaceutical and Drug Industries, National Research Centre, Cairo, 12622, Egypt.
| | - Sarah H M Khairat
- Department of Chemistry of Natural and Microbial Products, Division of Pharmaceutical and Drug Industries, National Research Centre, Cairo, 12622, Egypt
| | - Hamed I Ali
- Department of Pharmaceutical Sciences, Texas A&M University Irma Lerma Rangel College of Pharmacy Kingsville, TX 78363, United States; Department of Pharmaceutical Chemistry, College of Pharmacy, Helwan University, Cairo, Egypt
| | - Samia A Shouman
- Department of Cancer Biology, National Cancer Institute, Cairo University, Egypt
| | - Yasmin M Attia
- Department of Cancer Biology, National Cancer Institute, Cairo University, Egypt
| | - Mamdouh M Ali
- Department of Biochemistry, Division of Genetic Engineering and Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Abeer E Mahmoud
- Department of Biochemistry, Division of Genetic Engineering and Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Abeer H Abdel-Halim
- Department of Biochemistry, Division of Genetic Engineering and Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Amal A Fyiad
- Department of Biochemistry, Division of Genetic Engineering and Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Ashraf Tabll
- Department of Microbial Biotechnology, Division of Genetic Engineering & Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Reem El-Shenawy
- Department of Microbial Biotechnology, Division of Genetic Engineering & Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Yasmine S El Abd
- Department of Microbial Biotechnology, Division of Genetic Engineering & Biotechnology, National Research Centre, 12622, Cairo, Egypt
| | - Raghda Ramdan
- Radiobiology Unit, Belgian Nuclear Research Center (SCK•CEN), Mol, Belgium; Department of Basic Medical Sciences, Physiology Group, Ghent University, Ghent, Belgium
| | - Hoda I El Diwani
- Department of Chemistry of Natural and Microbial Products, Division of Pharmaceutical and Drug Industries, National Research Centre, Cairo, 12622, Egypt
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Gokare P, Navaraj A, Zhang S, Motoyama N, Sung SS, Finnberg NK. Targeting of Chk2 as a countermeasure to dose-limiting toxicity triggered by topoisomerase-II (TOP2) poisons. Oncotarget 2017; 7:29520-30. [PMID: 27121056 PMCID: PMC5045414 DOI: 10.18632/oncotarget.8790] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 03/28/2016] [Indexed: 11/29/2022] Open
Abstract
The DNA damage response (DDR) gene cell cycle checkpoint kinase 2 (Chk2) triggers programmed cell death and lethal radiation-induced toxicity in mice in vivo. However, it is not well established to what extent targeting of Chk2 may protect from dose-limiting toxicities (DLT) inflicted by mainstay cancer chemotherapy. We screened different classes of chemotherapy in wild type and Chk2-deficient cells. Here we show that loss of Chk2 protect from cell death in vitro and lethal toxicity in vivo following treatment with topoisomerase II (TOP2)–inhibitors whereas no such protection was observed following treatment with topoisomerase I (TOP1) inhibitors. Furthermore, through combined in silico and functional screens of the Diversity Set II (NCI/NTP) chemical library we identified the carbanilide-derivative NSC105171, also known as ptu-23, as a novel Chk2 inhibitor (Chk2i). Indeed, NSC105171 can be administered safely to mice to countermeasure etoposide-induced toxicity. Incorporation of Chk2i into chemotherapy protocols employing TOP2-inhibitors may be an effective strategy to prevent DLT's without interfering with treatment.
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Affiliation(s)
- Prashanth Gokare
- Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Department of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.,Penn State Hershey Cancer Institute, Penn State Hershey Medical Center, Hershey, PA 17104, USA
| | - Arunasalam Navaraj
- Penn State Hershey Cancer Institute, Penn State Hershey Medical Center, Hershey, PA 17104, USA
| | - Shengliang Zhang
- Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Department of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.,Penn State Hershey Cancer Institute, Penn State Hershey Medical Center, Hershey, PA 17104, USA
| | - Noboru Motoyama
- Institute of Longevity, Department of Cognitive Brain Sciences Research Institute, National Center for Geriatrics and Gerontology, Aichi 474-8511, Japan
| | - Shen-Shu Sung
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA 17104, USA
| | - Niklas K Finnberg
- Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Department of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.,Penn State Hershey Cancer Institute, Penn State Hershey Medical Center, Hershey, PA 17104, USA
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26
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Brandsma I, Fleuren ED, Williamson CT, Lord CJ. Directing the use of DDR kinase inhibitors in cancer treatment. Expert Opin Investig Drugs 2017; 26:1341-1355. [PMID: 28984489 PMCID: PMC6157710 DOI: 10.1080/13543784.2017.1389895] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
INTRODUCTION Defects in the DNA damage response (DDR) drive the development of cancer by fostering DNA mutation but also provide cancer-specific vulnerabilities that can be exploited therapeutically. The recent approval of three different PARP inhibitors for the treatment of ovarian cancer provides the impetus for further developing targeted inhibitors of many of the kinases involved in the DDR, including inhibitors of ATR, ATM, CHEK1, CHEK2, DNAPK and WEE1. Areas covered: We summarise the current stage of development of these novel DDR kinase inhibitors, and describe which predictive biomarkers might be exploited to direct their clinical use. Expert opinion: Novel DDR inhibitors present promising candidates in cancer treatment and have the potential to elicit synthetic lethal effects. In order to fully exploit their potential and maximize their utility, identifying highly penetrant predictive biomarkers of single agent and combinatorial DDR inhibitor sensitivity are critical. Identifying the optimal drug combination regimens that could used with DDR inhibitors is also a key objective.
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Affiliation(s)
- Inger Brandsma
- The CRUK Gene Function Laboratory and Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Emmy D.G. Fleuren
- The CRUK Gene Function Laboratory and Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Chris T. Williamson
- The CRUK Gene Function Laboratory and Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, SW3 6JB, UK
| | - Christopher J. Lord
- The CRUK Gene Function Laboratory and Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, SW3 6JB, UK
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27
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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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28
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Qiu Z, Oleinick NL, Zhang J. ATR/CHK1 inhibitors and cancer therapy. Radiother Oncol 2017; 126:450-464. [PMID: 29054375 DOI: 10.1016/j.radonc.2017.09.043] [Citation(s) in RCA: 210] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 08/01/2017] [Accepted: 09/30/2017] [Indexed: 02/06/2023]
Abstract
The cell cycle checkpoint proteins ataxia-telangiectasia-mutated-and-Rad3-related kinase (ATR) and its major downstream effector checkpoint kinase 1 (CHK1) prevent the entry of cells with damaged or incompletely replicated DNA into mitosis when the cells are challenged by DNA damaging agents, such as radiation therapy (RT) or chemotherapeutic drugs, that are the major modalities to treat cancer. This regulation is particularly evident in cells with a defective G1 checkpoint, a common feature of cancer cells, due to p53 mutations. In addition, ATR and/or CHK1 suppress replication stress (RS) by inhibiting excess origin firing, particularly in cells with activated oncogenes. Those functions of ATR/CHK1 make them ideal therapeutic targets. ATR/CHK1 inhibitors have been developed and are currently used either as single agents or paired with radiotherapy or a variety of genotoxic chemotherapies in preclinical and clinical studies. Here, we review the status of the development of ATR and CHK1 inhibitors. We also discuss the potential mechanisms by which ATR and CHK1 inhibition induces cell killing in the presence or absence of exogenous DNA damaging agents, such as RT and chemotherapeutic agents. Lastly, we discuss synthetic lethality interactions between the inhibition of ATR/CHK1 and defects in other DNA damage response (DDR) pathways/genes.
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Affiliation(s)
- Zhaojun Qiu
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, USA
| | - Nancy L Oleinick
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, USA; Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, USA
| | - Junran Zhang
- Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, USA; Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, USA.
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29
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Nickoloff JA, Boss MK, Allen CP, LaRue SM. Translational research in radiation-induced DNA damage signaling and repair. Transl Cancer Res 2017; 6:S875-S891. [PMID: 30574452 PMCID: PMC6298755 DOI: 10.21037/tcr.2017.06.02] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Radiotherapy is an effective tool in the fight against cancer. It is non-invasive and painless, and with advanced tumor imaging and beam control systems, radiation can be delivered to patients safely, generally with minor or no adverse side effects, accounting for its increasing use against a broad range of tumors. Tumors and normal cells respond to radiation-induced DNA damage by activating a complex network of DNA damage signaling and repair pathways that determine cell fate including survival, death, and genome stability. DNA damage response (DDR) proteins represent excellent targets to augment radiotherapy, and many agents that inhibit key response proteins are being combined with radiation and genotoxic chemotherapy in clinical trials. This review focuses on how insights into molecular mechanisms of DDR pathways are translated to small animal preclinical studies, to clinical studies of naturally occurring tumors in companion animals, and finally to human clinical trials. Companion animal studies, under the umbrella of comparative oncology, have played key roles in the development of clinical radiotherapy throughout its >100-year history. There is growing appreciation that rapid translation of basic knowledge of DNA damage and repair systems to improved radiotherapy practice requires a comprehensive approach that embraces the full spectrum of cancer research, with companion animal clinical trials representing a critical bridge between small animal preclinical studies, and human clinical trials.
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Affiliation(s)
- Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, Flint Animal Cancer Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Mary-Keara Boss
- Department of Environmental and Radiological Health Sciences, Flint Animal Cancer Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Christopher P Allen
- Department of Environmental and Radiological Health Sciences, Flint Animal Cancer Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Susan M LaRue
- Department of Environmental and Radiological Health Sciences, Flint Animal Cancer Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
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30
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Personalised Medicine: Genome Maintenance Lessons Learned from Studies in Yeast as a Model Organism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1007:157-178. [PMID: 28840557 DOI: 10.1007/978-3-319-60733-7_9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Yeast research has been tremendously contributing to the understanding of a variety of molecular pathways due to the ease of its genetic manipulation, fast doubling time as well as being cost-effective. The understanding of these pathways did not only help scientists learn more about the cellular functions but also assisted in deciphering the genetic and cellular defects behind multiple diseases. Hence, yeast research not only opened the doors for transforming basic research into applied research, but also paved the roads for improving diagnosis and innovating personalized therapy of different diseases. In this chapter, we discuss how yeast research has contributed to understanding major genome maintenance pathways such as the S-phase checkpoint activation pathways, repair via homologous recombination and non-homologous end joining as well as topoisomerases-induced protein linked DNA breaks repair. Defects in these pathways lead to neurodegenerative diseases and cancer. Thus, the understanding of the exact genetic defects underlying these diseases allowed the development of personalized medicine, improving the diagnosis and treatment and overcoming the detriments of current conventional therapies such as the side effects, toxicity as well as drug resistance.
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31
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Ronco C, Martin AR, Demange L, Benhida R. ATM, ATR, CHK1, CHK2 and WEE1 inhibitors in cancer and cancer stem cells. MEDCHEMCOMM 2016; 8:295-319. [PMID: 30108746 DOI: 10.1039/c6md00439c] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/25/2016] [Indexed: 12/15/2022]
Abstract
DNA inevitably undergoes a high number of damages throughout the cell cycle. To preserve the integrity of the genome, cells have developed a complex enzymatic machinery aimed at sensing and repairing DNA lesions, pausing the cell cycle to provide more time to repair, or induce apoptosis if damages are too severe. This so-called DNA-damage response (DDR) is yet considered as a major source of resistance to DNA-damaging treatments in oncology. Recently, it has been hypothesized that cancer stem cells (CSC), a sub-population of cancer cells particularly resistant and with tumour-initiating ability, allow tumour re-growth and cancer relapse. Therefore, DDR appears as a relevant target to sensitize cancer cells and cancer stem cells to classical radio- and chemotherapies as well as to overcome resistances. Moreover, the concept of synthetic lethality could be particularly efficiently exploited in DDR. Five kinases play pivotal roles in the DDR: ATM, ATR, CHK1, CHK2 and WEE1. Herein, we review the drugs targeting these proteins and the inhibitors used in the specific case of CSC. We also suggest molecules that may be of interest for preclinical and clinical researchers studying checkpoint inhibition to sensitize cancer and cancer stem cells to DNA-damaging treatments.
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Affiliation(s)
- Cyril Ronco
- Université Côte d'Azur , CNRS , Institut de Chimie de Nice , UMR7272 - Parc Valrose , 06108 Nice Cedex 2 , France . ; ; Tel: +33 4 92076143
| | - Anthony R Martin
- Université Côte d'Azur , CNRS , Institut de Chimie de Nice , UMR7272 - Parc Valrose , 06108 Nice Cedex 2 , France . ; ; Tel: +33 4 92076143
| | - Luc Demange
- Université Côte d'Azur , CNRS , Institut de Chimie de Nice , UMR7272 - Parc Valrose , 06108 Nice Cedex 2 , France . ; ; Tel: +33 4 92076143.,Université Paris Descartes , Sorbonne Paris Cité , UFR des Sciences Pharmaceutiques , 4 avenue de l'Observatoire , Paris Fr-75006 , France.,Université Paris Descartes , Sorbonne Paris Cité , UFR Biomédicale des Saints Pères , 45 rue des Saints Pères , France
| | - Rachid Benhida
- Université Côte d'Azur , CNRS , Institut de Chimie de Nice , UMR7272 - Parc Valrose , 06108 Nice Cedex 2 , France . ; ; Tel: +33 4 92076143
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32
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Chourasiya SS, Kathuria D, Nikam SS, Ramakrishnan A, Khullar S, Mandal SK, Chakraborti AK, Bharatam PV. Azine-Hydrazone Tautomerism of Guanylhydrazones: Evidence for the Preference Toward the Azine Tautomer. J Org Chem 2016; 81:7574-7583. [PMID: 27494613 DOI: 10.1021/acs.joc.6b01258] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Guanylhydrazones have been known for a long time and have wide applications in organic synthesis, medicinal chemistry, and material science; however, little attention has been paid toward their electronic and structural properties. Quantum chemical analysis on several therapeutically important guanylhydrazones indicated that all of them prefer the azine tautomeric state (by about 3-12 kcal/mol). A set of simple and conjugated azines were designed using quantum chemical methods, whose tautomeric preference toward the azine tautomer is in the range of 3-8 kcal/mol. Twenty new azines were synthesized and isolated in their neutral state. Variable temperature NMR study suggests existence of the azine tautomer even at higher temperatures with no traces of the hydrazone tautomer. The crystal structures of two representative compounds confirmed that the title compounds prefer to exist in their azine tautomeric form.
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Affiliation(s)
- Sumit S Chourasiya
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) , Sector 67, S.A.S. Nagar 160 062, Punjab, India
| | - Deepika Kathuria
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) , Sector 67, S.A.S. Nagar 160 062, Punjab, India
| | - Sampada S Nikam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) , Sector 67, S.A.S. Nagar 160 062, Punjab, India
| | - Ashok Ramakrishnan
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) , Sector 67, S.A.S. Nagar 160 062, Punjab, India
| | - Sadhika Khullar
- Department of Chemical Sciences, Indian Institute of Science Education and Research , Mohali Sector 81, S.A.S. Nagar 140 306, Punjab, India
| | - Sanjay K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research , Mohali Sector 81, S.A.S. Nagar 140 306, Punjab, India
| | - Asit K Chakraborti
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) , Sector 67, S.A.S. Nagar 160 062, Punjab, India
| | - Prasad V Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) , Sector 67, S.A.S. Nagar 160 062, Punjab, India
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33
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Sajesh BV, McManus KJ. Targeting SOD1 induces synthetic lethal killing in BLM- and CHEK2-deficient colorectal cancer cells. Oncotarget 2016; 6:27907-22. [PMID: 26318585 PMCID: PMC4695034 DOI: 10.18632/oncotarget.4875] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 07/21/2015] [Indexed: 12/22/2022] Open
Abstract
Cancer is a major cause of death throughout the world, and there is a large need for better and more personalized approaches to combat the disease. Over the past decade, synthetic lethal approaches have been developed that are designed to exploit the aberrant molecular origins (i.e. defective genes) that underlie tumorigenesis. BLM and CHEK2 are two evolutionarily conserved genes that are somatically altered in a number of tumor types. Both proteins normally function in preserving genome stability through facilitating the accurate repair of DNA double strand breaks. Thus, uncovering synthetic lethal interactors of BLM and CHEK2 will identify novel candidate drug targets and lead chemical compounds. Here we identify an evolutionarily conserved synthetic lethal interaction between SOD1 and both BLM and CHEK2 in two distinct cell models. Using quantitative imaging microscopy, real-time cellular analyses, colony formation and tumor spheroid models we show that SOD1 silencing and inhibition (ATTM and LCS-1 treatments), or the induction of reactive oxygen species (2ME2 treatment) induces selective killing within BLM- and CHEK2-deficient cells relative to controls. We further show that increases in reactive oxygen species follow SOD1 silencing and inhibition that are associated with the persistence of DNA double strand breaks, and increases in apoptosis. Collectively, these data identify SOD1 as a novel candidate drug target in BLM and CHEK2 cancer contexts, and further suggest that 2ME2, ATTM and LCS-1 are lead therapeutic compounds warranting further pre-clinical study.
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Affiliation(s)
- Babu V Sajesh
- Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada.,Research Institute of Oncology and Hematology, Winnipeg, Manitoba, Canada
| | - Kirk J McManus
- Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada.,Research Institute of Oncology and Hematology, Winnipeg, Manitoba, Canada
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34
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Woodard TL, Bolcun-Filas E. Prolonging Reproductive Life after Cancer: The Need for Fertoprotective Therapies. Trends Cancer 2016; 2:222-233. [DOI: 10.1016/j.trecan.2016.03.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 03/21/2016] [Accepted: 03/24/2016] [Indexed: 01/19/2023]
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35
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Samadder P, Aithal R, Belan O, Krejci L. Cancer TARGETases: DSB repair as a pharmacological target. Pharmacol Ther 2016; 161:111-131. [PMID: 26899499 DOI: 10.1016/j.pharmthera.2016.02.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cancer is a disease attributed to the accumulation of DNA damages due to incapacitation of DNA repair pathways resulting in genomic instability and a mutator phenotype. Among the DNA lesions, double stranded breaks (DSBs) are the most toxic forms of DNA damage which may arise as a result of extrinsic DNA damaging agents or intrinsic replication stress in fast proliferating cancer cells. Accurate repair of DSBs is therefore paramount to the cell survival, and several classes of proteins such as kinases, nucleases, helicases or core recombinational proteins have pre-defined jobs in precise execution of DSB repair pathways. On one hand, the proper functioning of these proteins ensures maintenance of genomic stability in normal cells, and on the other hand results in resistance to various drugs employed in cancer therapy and therefore presents a suitable opportunity for therapeutic targeting. Higher relapse and resistance in cancer patients due to non-specific, cytotoxic therapies is an alarming situation and it is becoming more evident to employ personalized treatment based on the genetic landscape of the cancer cells. For the success of personalized treatment, it is of immense importance to identify more suitable targetable proteins in DSB repair pathways and also to explore new synthetic lethal interactions with these pathways. Here we review the various alternative approaches to target the various protein classes termed as cancer TARGETases in DSB repair pathway to obtain more beneficial and selective therapy.
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Affiliation(s)
- Pounami Samadder
- National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital in Brno, 60200 Brno, Czech Republic
| | - Rakesh Aithal
- National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic; Department of Biology, Masaryk University, 62500 Brno, Czech Republic
| | - Ondrej Belan
- Department of Biology, Masaryk University, 62500 Brno, Czech Republic
| | - Lumir Krejci
- National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital in Brno, 60200 Brno, Czech Republic; Department of Biology, Masaryk University, 62500 Brno, Czech Republic.
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36
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Cellular Pathways in Response to Ionizing Radiation and Their Targetability for Tumor Radiosensitization. Int J Mol Sci 2016; 17:ijms17010102. [PMID: 26784176 PMCID: PMC4730344 DOI: 10.3390/ijms17010102] [Citation(s) in RCA: 273] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 12/22/2015] [Accepted: 12/25/2015] [Indexed: 12/20/2022] Open
Abstract
During the last few decades, improvements in the planning and application of radiotherapy in combination with surgery and chemotherapy resulted in increased survival rates of tumor patients. However, the success of radiotherapy is impaired by two reasons: firstly, the radioresistance of tumor cells and, secondly, the radiation-induced damage of normal tissue cells located in the field of ionizing radiation. These limitations demand the development of drugs for either radiosensitization of tumor cells or radioprotection of normal tissue cells. In order to identify potential targets, a detailed understanding of the cellular pathways involved in radiation response is an absolute requirement. This review describes the most important pathways of radioresponse and several key target proteins for radiosensitization.
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37
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Finnberg NK, Gokare P, Navaraj A, Lang Kuhs KA, Cerniglia G, Yagita H, Takeda K, Motoyama N, El-Deiry WS. Agonists of the TRAIL Death Receptor DR5 Sensitize Intestinal Stem Cells to Chemotherapy-Induced Cell Death and Trigger Gastrointestinal Toxicity. Cancer Res 2015; 76:700-12. [PMID: 26609054 DOI: 10.1158/0008-5472.can-15-2759] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 10/26/2015] [Indexed: 12/13/2022]
Abstract
The combination of TRAIL death receptor agonists and radiochemotherapy to treat advanced cancers continues to be investigated in clinical trials. We previously showed that normal cells with a functional DNA damage response (DDR) upregulate the expression of death-inducing receptor DR5/TRAILR2/TNFRSF10B in a p53-dependent manner that sensitizes them to treatment with DR5 agonists. However, it is unclear if targeting DR5 selectively sensitizes cancer cells to agonist treatment following exposure to DNA-damaging chemotherapy, and to what extent normal tissues are targeted. Here, we show that the combined administration of the DR5 agonistic monoclonal antibody (mAb) and chemotherapy to wild-type mice triggered synergistic gastrointestinal toxicities (GIT) that were associated with the death of Lgr5(+) crypt base columnar stem cells in a p53- and DR5-dependent manner. Furthermore, we confirmed that normal human epithelial cells treated with the human DR5-agonistic mAb and chemotherapeutic agents were also greatly sensitized to cell death. Interestingly, our data also indicated that genetic or pharmacologic targeting of Chk2 may counteract GIT without negatively affecting the antitumor responses of combined DR5 agonist/chemotherapy treatment, further linking the DDR to TRAIL death receptor signaling in normal cells. In conclusion, the combination of DR5-targeting agonistic mAbs with DNA damaging chemotherapy may pose a risk of developing toxicity-induced conditions, and the effects of mAb-based strategies on the dose-limiting toxicity of chemotherapy must be considered when establishing new combination therapies.
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Affiliation(s)
- Niklas K Finnberg
- Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Departmental of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania. Division of Hematology/Oncology, Penn State Hershey Cancer Institute, Hershey, Pennsylvania
| | - Prashanth Gokare
- Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Departmental of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania. Division of Hematology/Oncology, Penn State Hershey Cancer Institute, Hershey, Pennsylvania
| | - Arunasalam Navaraj
- Division of Hematology/Oncology, Penn State Hershey Cancer Institute, Hershey, Pennsylvania
| | - Krystle A Lang Kuhs
- Infections and Immunoepidemiology Branch, Division of Cancer Epidemiology and Infections/National Cancer Institute, Bethesda, Maryland
| | - George Cerniglia
- Department of Radiation Oncology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hideo Yagita
- Department of Immunology, Juntendo University School of Medicine, Tokyo, Japan
| | - Kazuyoshi Takeda
- Department of Immunology, Juntendo University School of Medicine, Tokyo, Japan
| | - Noboru Motoyama
- Department of Cognitive Brain Sciences, Research Institute, National Center for Geriatrics and Gerontology, Aichi, Japan
| | - Wafik S El-Deiry
- Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Departmental of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania. Division of Hematology/Oncology, Penn State Hershey Cancer Institute, Hershey, Pennsylvania.
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38
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DNA Damage Signalling and Repair Inhibitors: The Long-Sought-After Achilles' Heel of Cancer. Biomolecules 2015; 5:3204-59. [PMID: 26610585 PMCID: PMC4693276 DOI: 10.3390/biom5043204] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 11/09/2015] [Indexed: 12/16/2022] Open
Abstract
For decades, radiotherapy and chemotherapy were the two only approaches exploiting DNA repair processes to fight against cancer. Nowadays, cancer therapeutics can be a major challenge when it comes to seeking personalized targeted medicine that is both effective and selective to the malignancy. Over the last decade, the discovery of new targeted therapies against DNA damage signalling and repair has offered the possibility of therapeutic improvements in oncology. In this review, we summarize the current knowledge of DNA damage signalling and repair inhibitors, their molecular and cellular effects, and future therapeutic use.
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Agarwal S, Bell CM, Rothbart SB, Moran RG. AMP-activated Protein Kinase (AMPK) Control of mTORC1 Is p53- and TSC2-independent in Pemetrexed-treated Carcinoma Cells. J Biol Chem 2015; 290:27473-86. [PMID: 26391395 PMCID: PMC4646000 DOI: 10.1074/jbc.m115.665133] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 09/18/2015] [Indexed: 12/25/2022] Open
Abstract
The key sensor of energy status in mammalian cells, AMP-activated protein kinase (AMPK), can also be activated by the AMP analog aminoimidazolecarboxamide nucleoside monophosphate (ZMP) generated directly from aminoimidazolecarboxamide ribonucleoside (AICAR) or from inhibition of purine synthesis by the antifolate pemetrexed (PTX), a drug used extensively in the treatment of lung cancers. Despite this common mechanism, signaling downstream of AMPK activated by PTX or AICAR differed. AICAR-activated AMPK inhibited mTORC1 both directly by phosphorylation of the mTORC1 subunit Raptor and indirectly by phosphorylation of the regulator TSC2. In contrast, PTX-activated AMPK inhibited mTORC1 solely through Raptor phosphorylation. This dichotomy was due to p53 function. Transcription of p53 target genes, including TSC2, was activated by AICAR but not by PTX. Although both PTX and AICAR stabilized p53, only AICAR activated Chk2 phosphorylation, stimulating p53-dependent transcription. However, Raptor phosphorylation by AMPK was independent of p53 and was sufficient, after PTX treatment, to inhibit mTORC1. We concluded that PTX effects on mTORC1 were independent of TSC2 and p53 and that the activation of a p53 transcriptional response by AICAR was due to an activation of Chk2 that was not elicited by PTX.
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Affiliation(s)
- Stuti Agarwal
- From the Department of Pharmacology and Toxicology and the Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia 23298 and
| | - Catherine M Bell
- From the Department of Pharmacology and Toxicology and the Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia 23298 and
| | - Scott B Rothbart
- the Center for Epigenetics, Van Andel Research Institute, Grand Rapids, Michigan 49503
| | - Richard G Moran
- From the Department of Pharmacology and Toxicology and the Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia 23298 and
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Mihailovich M, Bremang M, Spadotto V, Musiani D, Vitale E, Varano G, Zambelli F, Mancuso FM, Cairns DA, Pavesi G, Casola S, Bonaldi T. miR-17-92 fine-tunes MYC expression and function to ensure optimal B cell lymphoma growth. Nat Commun 2015; 6:8725. [PMID: 26555894 PMCID: PMC4667639 DOI: 10.1038/ncomms9725] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 09/22/2015] [Indexed: 01/07/2023] Open
Abstract
The synergism between c-MYC and miR-17-19b, a truncated version of the miR-17-92 cluster, is well-documented during tumor initiation. However, little is known about miR-17-19b function in established cancers. Here we investigate the role of miR-17-19b in c-MYC-driven lymphomas by integrating SILAC-based quantitative proteomics, transcriptomics and 3′ untranslated region (UTR) analysis upon miR-17-19b overexpression. We identify over one hundred miR-17-19b targets, of which 40% are co-regulated by c-MYC. Downregulation of a new miR-17/20 target, checkpoint kinase 2 (Chek2), increases the recruitment of HuR to c-MYC transcripts, resulting in the inhibition of c-MYC translation and thus interfering with in vivo tumor growth. Hence, in established lymphomas, miR-17-19b fine-tunes c-MYC activity through a tight control of its function and expression, ultimately ensuring cancer cell homeostasis. Our data highlight the plasticity of miRNA function, reflecting changes in the mRNA landscape and 3′ UTR shortening at different stages of tumorigenesis. The synergism between c-MYC and miR-17-19b plays an important role in lymphoma initiation. In this study, the authors identify a panel of targets co-regulated by miR-17-19b and in MYC-driven lymphoma and unravel the molecular mechanism through which miR-17-19b inhibits MYC translation.
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Affiliation(s)
- Marija Mihailovich
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, Milan 20139, Italy
| | - Michael Bremang
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, Milan 20139, Italy
| | - Valeria Spadotto
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, Milan 20139, Italy
| | - Daniele Musiani
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, Milan 20139, Italy
| | - Elena Vitale
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, Milan 20139, Italy
| | - Gabriele Varano
- Units of Genetics of B cells and lymphomas, IFOM, FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
| | | | - Francesco M Mancuso
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, Milan 20139, Italy
| | - David A Cairns
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, Milan 20139, Italy
| | - Giulio Pavesi
- Department of Biosciences, Milan University, Milan 20133, Italy
| | - Stefano Casola
- Units of Genetics of B cells and lymphomas, IFOM, FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
| | - Tiziana Bonaldi
- Department of Experimental Oncology, European Institute of Oncology, Via Adamello 16, Milan 20139, Italy
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Manic G, Obrist F, Sistigu A, Vitale I. Trial Watch: Targeting ATM-CHK2 and ATR-CHK1 pathways for anticancer therapy. Mol Cell Oncol 2015; 2:e1012976. [PMID: 27308506 PMCID: PMC4905354 DOI: 10.1080/23723556.2015.1012976] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 01/25/2015] [Accepted: 01/26/2015] [Indexed: 02/08/2023]
Abstract
The ataxia telangiectasia mutated serine/threonine kinase (ATM)/checkpoint kinase 2 (CHEK2, best known as CHK2) and the ATM and Rad3-related serine/threonine kinase (ATR)/CHEK1 (best known as CHK1) cascades are the 2 major signaling pathways driving the DNA damage response (DDR), a network of processes crucial for the preservation of genomic stability that act as a barrier against tumorigenesis and tumor progression. Mutations and/or deletions of ATM and/or CHK2 are frequently found in tumors and predispose to cancer development. In contrast, the ATR-CHK1 pathway is often upregulated in neoplasms and is believed to promote tumor growth, although some evidence indicates that ATR and CHK1 may also behave as haploinsufficient oncosuppressors, at least in a specific genetic background. Inactivation of the ATM-CHK2 and ATR-CHK1 pathways efficiently sensitizes malignant cells to radiotherapy and chemotherapy. Moreover, ATR and CHK1 inhibitors selectively kill tumor cells that present high levels of replication stress, have a deficiency in p53 (or other DDR players), or upregulate the ATR-CHK1 module. Despite promising preclinical results, the clinical activity of ATM, ATR, CHK1, and CHK2 inhibitors, alone or in combination with other therapeutics, has not yet been fully demonstrated. In this Trial Watch, we give an overview of the roles of the ATM-CHK2 and ATR-CHK1 pathways in cancer initiation and progression, and summarize the results of clinical studies aimed at assessing the safety and therapeutic profile of regimens based on inhibitors of ATR and CHK1, the only 2 classes of compounds that have so far entered clinics.
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Affiliation(s)
| | - Florine Obrist
- Université Paris-Sud/Paris XI; Le Kremlin-Bicêtre, France
- INSERM, UMRS1138; Paris, France
- Equipe 11 labelisée par la Ligue Nationale contre le Cancer; Centre de Recherche des Cordeliers; Paris, France
- Gustave Roussy Cancer Campus; Villejuif, France
| | | | - Ilio Vitale
- Regina Elena National Cancer Institute; Rome, Italy
- Department of Biology, University of Rome “TorVergata”; Rome, Italy
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Advani SJ, Camargo MF, Seguin L, Mielgo A, Anand S, Hicks AM, Aguilera J, Franovic A, Weis SM, Cheresh DA. Kinase-independent role for CRAF-driving tumour radioresistance via CHK2. Nat Commun 2015; 6:8154. [PMID: 26333361 PMCID: PMC4559870 DOI: 10.1038/ncomms9154] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 07/24/2015] [Indexed: 12/19/2022] Open
Abstract
Although oncology therapy regimens commonly include radiation and genotoxic drugs, tumour cells typically develop resistance to these interventions. Here we report that treatment of tumours with ionizing radiation or genotoxic drugs drives p21-activated kinase 1 (PAK1)-mediated phosphorylation of CRAF on Serine 338 (pS338) triggering a kinase-independent mechanism of DNA repair and therapeutic resistance. CRAF pS338 recruits CHK2, a cell cycle checkpoint kinase involved in DNA repair, and promotes CHK2 phosphorylation/activation to enhance the tumour cell DNA damage response. Accordingly, a phospho-mimetic mutant of CRAF (S338D) is sufficient to induce the CRAF/CHK2 association enhancing tumour radioresistance, while an allosteric CRAF inhibitor sensitizes tumour cells to ionizing radiation or genotoxic drugs. Our findings establish a role for CRAF in the DNA damage response that is independent from its canonical function as a kinase. Tumors hijack cellular pathways to evade the effects of cancer therapy. Here, Advani et al. show that DNA damage-induced phosphorylation of CRAF Serine 338 triggers DNA repair by recruiting CHK2, highlighting a role for CRAF independent from its canonical function as a kinase.
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Affiliation(s)
- Sunil J Advani
- Department of Radiation Medicine and Applied Sciences at the UC San Diego Moores Cancer Center, University of California, San Diego, La Jolla, California 92093, USA
| | - Maria Fernanda Camargo
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Laetitia Seguin
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Ainhoa Mielgo
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Sudarshan Anand
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Angel M Hicks
- Department of Radiation Medicine and Applied Sciences at the UC San Diego Moores Cancer Center, University of California, San Diego, La Jolla, California 92093, USA
| | - Joseph Aguilera
- Department of Radiation Medicine and Applied Sciences at the UC San Diego Moores Cancer Center, University of California, San Diego, La Jolla, California 92093, USA
| | - Aleksandra Franovic
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - Sara M Weis
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
| | - David A Cheresh
- Department of Pathology at the UC San Diego Moores Cancer Center and Sanford Consortium for Regenerative Medicine, University of California, San Diego, 3855 Health Science Drive, La Jolla, California 92037, USA
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Zilla MK, Nayak D, Amin H, Nalli Y, Rah B, Chakraborty S, Kitchlu S, Goswami A, Ali A. 4′-Demethyl-deoxypodophyllotoxin glucoside isolated from Podophyllum hexandrum exhibits potential anticancer activities by altering Chk-2 signaling pathway in MCF-7 breast cancer cells. Chem Biol Interact 2014; 224:100-7. [DOI: 10.1016/j.cbi.2014.09.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 09/23/2014] [Accepted: 09/25/2014] [Indexed: 01/12/2023]
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Checkpoint kinase Chk2 controls renal Cyp27b1 expression, calcitriol formation, and calcium-phosphate metabolism. Pflugers Arch 2014; 467:1871-80. [PMID: 25319519 DOI: 10.1007/s00424-014-1625-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 09/29/2014] [Accepted: 10/01/2014] [Indexed: 02/08/2023]
Abstract
Checkpoint kinase 2 (Chk2) is the main effector kinase of ataxia telangiectasia mutated (ATM) and responsible for cell cycle regulation. ATM signaling has been shown to upregulate interferon-regulating factor-1 (IRF-1), a transcription factor also expressed in the kidney. Calcitriol (1,25 (OH)2D3), a major regulator of mineral metabolism, is generated by 25-hydroxyvitamin D 1α-hydroxylase in the kidney. Since 25-hydroxyvitamin D 1α-hydroxylase expression is enhanced by IRF-1, the present study explored the role of Chk2 for calcitriol formation and mineral metabolism. Chk2-deficient mice (chk2 (-/-)) were compared to wild-type mice (chk2 (+/+)). Transcript levels of renal 25-hydroxyvitamin D 1α-hydroxylase, Chk2, and IRF-1 were determined by RT-PCR; Klotho expression by Western blotting; bone density by μCT analysis; serum or plasma 1,25 (OH)2D3, PTH, and C-terminal FGF23 concentrations by immunoassays; and serum, fecal, and urinary calcium and phosphate concentrations by photometry. The renal expression of IRF-1 and 25-hydroxyvitamin D 1α-hydroxylase as well as serum 1,25 (OH)2D3 and FGF23 levels were significantly lower in chk2 (-/-) mice compared to chk2 (+/+) mice. Plasma PTH was not different between the genotypes. Renal calcium and phosphate excretion were significantly higher in chk2 (-/-) mice than in chk2 (+/+) mice despite hypophosphatemia and normocalcemia. Bone density was not different between the genotypes. We conclude that Chk2 regulates renal 25-hydroxyvitamin D 1α-hydroxylase expression thereby impacting on calcium and phosphate metabolism.
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Checkpoint kinase inhibitor AZD7762 overcomes cisplatin resistance in clear cell carcinoma of the ovary. Int J Gynecol Cancer 2014; 24:61-9. [PMID: 24362713 DOI: 10.1097/igc.0000000000000014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE Checkpoint kinase (Chk) inhibitors are thought to increase the cytotoxic effects of DNA-damaging agents and are undergoing clinical trials. The present study was aimed to assess the potential to use the Chk1 and Chk2 inhibitor, AZD7762, with other anticancer agents in chemotherapy to treat ovarian clear cell carcinoma. METHODS Four ovarian clear cell carcinoma cell lines were used in this study. We treated the cells with AZD7762 and anticancer agents, then assessed cell viability, cell cycle distribution, apoptosis, and the expression of protein in apoptotic pathways and molecules downstream of the Chk signaling pathways. We also investigated the effects of these drug combinations on tumor growth in a nude mouse xenograft model. RESULTS Synergistic effects from the combination of AZD7762 and cisplatin were observed in all 4 cell lines. However, we observed additive effects when AZD7762 was combined with paclitaxel on all cell lines tested. AZD7762 effectively suppressed the Chk signaling pathways activated by cisplatin, dramatically enhanced expression of phosphorylated H2A.X, cleaved caspase 9 and PARP, decreased the proportion of cells in the gap 0/ gap 1 phase and the synthesis-phase fraction, and increased apoptotic cells. Combinations of small interfering RNA against Chk 1 and small interfering RNA against Chk2 enhanced the cytotoxic effect of cisplatin in both RMG-I and KK cells. Finally, treating mice-bearing RMG-I with AZD7762 and cisplatin significantly suppressed growth of tumors in a xenograft model. CONCLUSIONS The present study indicates that chemotherapy with AZD7762 and cisplatin should be explored as a treatment modality for women with ovarian clear cell carcinoma.
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Abstract
![]()
The
concept of synthetic lethality (the creation of a lethal phenotype
from the combined effects of mutations in two or more genes) has recently
been exploited in various efforts to develop new genotype-selective
anticancer therapeutics. These efforts include screening for novel
anticancer agents, identifying novel therapeutic targets, characterizing
mechanisms of resistance to targeted therapy, and improving efficacies
through the rational design of combination therapy. This review discusses
recent developments in synthetic lethality anticancer therapeutics,
including poly ADP-ribose polymerase inhibitors for BRCA1- and BRCA2-mutant cancers, checkpoint inhibitors
for p53 mutant cancers, and small molecule agents targeting RAS gene mutant cancers. Because cancers are caused by mutations
in multiple genes and abnormalities in multiple signaling pathways,
synthetic lethality for a specific tumor suppressor gene or oncogene
is likely cell context-dependent. Delineation of the mechanisms underlying
synthetic lethality and identification of treatment response biomarkers
will be critical for the success of synthetic lethality anticancer
therapy.
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Affiliation(s)
- Bingliang Fang
- Department of Thoracic and Cardiovascular Surgery, Unit 1489, The University of Texas MD Anderson Cancer Center , 1515 Holcombe Boulevard, Houston, Texas 77030, United States
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Checkpoint kinase 2 (Chk2) supports sensitivity to platinum-based treatment in high grade serous ovarian cancer. Gynecol Oncol 2014; 133:591-8. [DOI: 10.1016/j.ygyno.2014.03.557] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 03/14/2014] [Accepted: 03/16/2014] [Indexed: 11/24/2022]
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Ow GS, Ivshina AV, Fuentes G, Kuznetsov VA. Identification of two poorly prognosed ovarian carcinoma subtypes associated with CHEK2 germ-line mutation and non-CHEK2 somatic mutation gene signatures. Cell Cycle 2014; 13:2262-80. [PMID: 24879340 PMCID: PMC4111681 DOI: 10.4161/cc.29271] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 05/14/2014] [Accepted: 05/17/2014] [Indexed: 01/08/2023] Open
Abstract
High-grade serous ovarian cancer (HG-SOC), a major histologic type of epithelial ovarian cancer (EOC), is a poorly-characterized, heterogeneous and lethal disease where somatic mutations of TP53 are common and inherited loss-of-function mutations in BRCA1/2 predispose to cancer in 9.5-13% of EOC patients. However, the overall burden of disease due to either inherited or sporadic mutations is not known. We performed bioinformatics analyses of mutational and clinical data of 334 HG-SOC tumor samples from The Cancer Genome Atlas to identify novel tumor-driving mutations, survival-significant patient subgroups and tumor subtypes potentially driven by either hereditary or sporadic factors. We identified a sub-cluster of high-frequency mutations in 22 patients and 58 genes associated with DNA damage repair, apoptosis and cell cycle. Mutations of CHEK2, observed with the highest intensity, were associated with poor therapy response and overall survival (OS) of these patients (P = 8.00e-05), possibly due to detrimental effect of mutations at the nuclear localization signal. A 21-gene mutational prognostic signature significantly stratifies patients into relatively low or high-risk subgroups with 5-y OS of 37% or 6%, respectively (P = 7.31e-08). Further analysis of these genes and high-risk subgroup revealed 2 distinct classes of tumors characterized by either germline mutations of genes such as CHEK2, RPS6KA2 and MLL4, or somatic mutations of other genes in the signature. Our results could provide improvement in prediction and clinical management of HG-SOC, facilitate our understanding of this complex disease, guide the design of targeted therapeutics and improve screening efforts to identify women at high-risk of hereditary ovarian cancers distinct from those associated with BRCA1/2 mutations.
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Affiliation(s)
| | | | - Gloria Fuentes
- Bioinformatics Institute; A*STAR; Singapore
- Center for Life Science Technologies (CLST); RIKEN; Saitama, Japan
| | - Vladimir A Kuznetsov
- Bioinformatics Institute; A*STAR; Singapore
- Division of Software & Information Systems; School of Computer Engineering; Nanyang Technological University; Singapore
- School for Integrative Science and Engineering; National University of Singapore; Singapore
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Lin CY, Wang YL. Novel design strategy for checkpoint kinase 2 inhibitors using pharmacophore modeling, combinatorial fusion, and virtual screening. BIOMED RESEARCH INTERNATIONAL 2014; 2014:359494. [PMID: 24864236 PMCID: PMC4017722 DOI: 10.1155/2014/359494] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 02/19/2014] [Indexed: 11/24/2022]
Abstract
Checkpoint kinase 2 (Chk2) has a great effect on DNA-damage and plays an important role in response to DNA double-strand breaks and related lesions. In this study, we will concentrate on Chk2 and the purpose is to find the potential inhibitors by the pharmacophore hypotheses (PhModels), combinatorial fusion, and virtual screening techniques. Applying combinatorial fusion into PhModels and virtual screening techniques is a novel design strategy for drug design. We used combinatorial fusion to analyze the prediction results and then obtained the best correlation coefficient of the testing set (r test) with the value 0.816 by combining the Best(train)Best(test) and Fast(train)Fast(test) prediction results. The potential inhibitors were selected from NCI database by screening according to Best(train)Best(test) + Fast(train)Fast(test) prediction results and molecular docking with CDOCKER docking program. Finally, the selected compounds have high interaction energy between a ligand and a receptor. Through these approaches, 23 potential inhibitors for Chk2 are retrieved for further study.
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Affiliation(s)
- Chun-Yuan Lin
- Department of Computer Science and Information Engineering, Chang Gung University, Taoyuan 33302, Taiwan
- Research Center for Emerging Viral Infections, Chang Gung University, Taoyuan 33302, Taiwan
| | - Yen-Ling Wang
- Department of Computer Science and Information Engineering, Chang Gung University, Taoyuan 33302, Taiwan
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Kleiman LB, Krebs AM, Kim SY, Hong TS, Haigis KM. Comparative analysis of radiosensitizers for K-RAS mutant rectal cancers. PLoS One 2013; 8:e82982. [PMID: 24349411 PMCID: PMC3861465 DOI: 10.1371/journal.pone.0082982] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 10/29/2013] [Indexed: 02/07/2023] Open
Abstract
Approximately 40% of rectal cancers harbor activating K-RAS mutations, and these mutations are associated with poor clinical response to chemoradiotherapy. We aimed to identify small molecule inhibitors (SMIs) that synergize with ionizing radiation (IR) ("radiosensitizers") that could be incorporated into current treatment strategies for locally advanced rectal cancers (LARCs) expressing mutant K-RAS. We first optimized a high-throughput assay for measuring individual and combined effects of SMIs and IR that produces similar results to the gold standard colony formation assay. Using this screening platform and K-RAS mutant rectal cancer cell lines, we tested SMIs targeting diverse signaling pathways for radiosensitizing activity and then evaluated our top hits in follow-up experiments. The two most potent radiosensitizers were the Chk1/2 inhibitor AZD7762 and the PI3K/mTOR inhibitor BEZ235. The chemotherapeutic agent 5-fluorouracil (5-FU), which is used to treat LARC, synergized with AZD7762 and enhanced radiosensitization by AZD7762. This study is the first to compare different SMIs in combination with IR for the treatment of K-RAS mutant rectal cancer, and our findings suggest that Chk1/2 inhibitors should be evaluated in new clinical trials for LARC.
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Affiliation(s)
- Laura B. Kleiman
- Molecular Pathology Unit, Center for Cancer Research and Center for Systems Biology, Massachusetts General Hospital, Charlestown, Massachusetts, United States of America
| | - Angela M. Krebs
- Molecular Pathology Unit, Center for Cancer Research and Center for Systems Biology, Massachusetts General Hospital, Charlestown, Massachusetts, United States of America
- Institute of Molecular Medicine and Cell Research, Albert Ludwigs University Freiburg, Germany
| | - Stephen Y. Kim
- Molecular Pathology Unit, Center for Cancer Research and Center for Systems Biology, Massachusetts General Hospital, Charlestown, Massachusetts, United States of America
| | - Theodore S. Hong
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Kevin M. Haigis
- Molecular Pathology Unit, Center for Cancer Research and Center for Systems Biology, Massachusetts General Hospital, Charlestown, Massachusetts, United States of America
- * E-mail:
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