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Kobayashi G, Sentani K, Hattori T, Yamamoto Y, Imai T, Sakamoto N, Kuraoka K, Oue N, Sasaki N, Taniyama K, Yasui W. Clinicopathological significance of claspin overexpression and its association with spheroid formation in gastric cancer. Hum Pathol 2018; 84:8-17. [PMID: 30240769 DOI: 10.1016/j.humpath.2018.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 08/31/2018] [Accepted: 09/06/2018] [Indexed: 01/06/2023]
Abstract
Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide. Spheroid colony formation is a useful method to identify cancer stem cells (CSCs). The aim of this study was to identify a novel prognostic marker or therapeutic target for GC using a method to identify CSCs. We analyzed the microarray data in spheroid body-forming and parental cells and focused on the CLSPN gene because it is overexpressed in the spheroid body-forming cells in both the GC cell lines MKN-45 and MKN-74. Quantitative reverse-transcription polymerase chain reaction analysis revealed that CLSPN messenger RNA expression was up-regulated in GC cell lines MKN-45, MKN-74, and TMK-1. Immunohistochemistry of claspin showed that 94 (47%) of 203 GC cases were positive. Claspin-positive GC cases were associated with higher T and N grades, tumor stage, lymphatic invasion, and poor prognosis. In addition, claspin expression was coexpressed with CD44, human epidermal growth factor receptor type 2, and p53. CLSPN small interfering RNA treatment decreased GC cell proliferation and invasion. These results indicate that the expression of claspin might be a key regulator in the progression of GC and might play an important role in CSCs of GC.
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Affiliation(s)
- Go Kobayashi
- Department of Molecular Pathology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, 734-8551 Japan; Department of Pathology, Kure-Kyosai Hospital, Federation of National Public Service Personnel Mutual Aid Associations, Hiroshima, 737-8505 Japan
| | - Kazuhiro Sentani
- Department of Molecular Pathology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, 734-8551 Japan.
| | - Takuya Hattori
- Department of Molecular Pathology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, 734-8551 Japan
| | - Yuji Yamamoto
- Department of Molecular Pathology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, 734-8551 Japan
| | - Takeharu Imai
- Department of Surgical Oncology, Graduate School of Medicine, Gifu University, Gifu, 501-1194 Japan
| | - Naoya Sakamoto
- Department of Molecular Pathology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, 734-8551 Japan
| | - Kazuya Kuraoka
- Department of Pathology, National Hospital Organization Kure Medical Center and Chugoku Cancer Center, Kure-City, Hiroshima, 737-0023 Japan
| | - Naohide Oue
- Department of Molecular Pathology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, 734-8551 Japan
| | - Naomi Sasaki
- Department of Pathology, Kure-Kyosai Hospital, Federation of National Public Service Personnel Mutual Aid Associations, Hiroshima, 737-8505 Japan
| | - Kiyomi Taniyama
- Department of Pathology, National Hospital Organization Kure Medical Center and Chugoku Cancer Center, Kure-City, Hiroshima, 737-0023 Japan
| | - Wataru Yasui
- Department of Molecular Pathology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, 734-8551 Japan
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202
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Dandoulaki M, Petsalaki E, Sumpton D, Zanivan S, Zachos G. Src activation by Chk1 promotes actin patch formation and prevents chromatin bridge breakage in cytokinesis. J Cell Biol 2018; 217:3071-3089. [PMID: 29954829 PMCID: PMC6122982 DOI: 10.1083/jcb.201802102] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 04/16/2018] [Accepted: 06/03/2018] [Indexed: 12/23/2022] Open
Abstract
In cytokinesis with chromatin bridges, cells delay abscission and retain actin patches at the intercellular canal to prevent chromosome breakage. In this study, we show that inhibition of Src, a protein-tyrosine kinase that regulates actin dynamics, or Chk1 kinase correlates with chromatin breakage and impaired formation of actin patches but not with abscission in the presence of chromatin bridges. Chk1 is required for optimal localization and complete activation of Src. Furthermore, Chk1 phosphorylates human Src at serine 51, and phosphorylated Src localizes to actin patches, the cell membrane, or the nucleus. Nonphosphorylatable mutation of S51 to alanine reduces Src catalytic activity and impairs formation of actin patches, whereas expression of a phosphomimicking Src-S51D protein rescues actin patches and prevents chromatin breakage in Chk1-deficient cells. We propose that Chk1 phosphorylates Src-S51 to fully induce Src kinase activity and that phosphorylated Src promotes formation of actin patches and stabilizes chromatin bridges. These results identify proteins that regulate formation of actin patches in cytokinesis.
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Affiliation(s)
| | - Eleni Petsalaki
- Department of Biology, University of Crete, Heraklion, Greece
| | - David Sumpton
- Cancer Research UK Beatson Institute, Glasgow, Scotland, UK
| | - Sara Zanivan
- Cancer Research UK Beatson Institute, Glasgow, Scotland, UK
- Institute of Cancer Sciences, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, Scotland, UK
| | - George Zachos
- Department of Biology, University of Crete, Heraklion, Greece
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203
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Liu S, Yao X, Zhang D, Sheng J, Wen X, Wang Q, Chen G, Li Z, Du Z, Zhang X. Analysis of Transcription Factor-Related Regulatory Networks Based on Bioinformatics Analysis and Validation in Hepatocellular Carcinoma. BIOMED RESEARCH INTERNATIONAL 2018; 2018:1431396. [PMID: 30228980 PMCID: PMC6136478 DOI: 10.1155/2018/1431396] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 07/03/2018] [Accepted: 07/25/2018] [Indexed: 02/07/2023]
Abstract
Hepatocellular carcinoma (HCC) accounts for a significant proportion of liver cancer, which has become the second most common cause of cancer-related mortality worldwide. To investigate the potential mechanisms of invasion and progression of HCC, bioinformatics analysis and validation by qRT-PCR were performed. We found 237 differentially expressed genes (DEGs) including EGR1, FOS, and FOSB, which were three cancer-related transcription factors. Subsequently, we constructed TF-gene network and miRNA-TF-mRNA network based on data obtained from mRNA and miRNA expression profiles for analysis of HCC. We found that 42 key genes from the TF-gene network including EGR1, FOS, and FOSB were most enriched in the p53 signaling pathway. The qRT-PCR data confirmed that mRNA levels of EGR1, FOS, and FOSB all were decreased in HCC tissues. In addition, we confirmed that the mRNA levels of CCNB1, CCNB2, and CHEK1, three key markers of the p53 signaling pathway, were all increased in HCC tissues by bioinformatics analysis and qRT-PCR validation. Therefore, we speculated that miR-181a-5p, which was upregulated in HCC tissues, could regulate FOS and EGR1 to promote the invasion and progression of HCC by p53 signaling pathway. Overall, the study provides support for the possible mechanisms of progression in HCC.
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Affiliation(s)
- Shui Liu
- Department of Hepatobiliary and Pancreatic Surgery, The Second Hospital of Jilin University, Changchun 130041, China
- Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases, The Second Hospital of Jilin University, Changchun 130041, China
| | - Xiaoxiao Yao
- Department of Hepatobiliary and Pancreatic Surgery, The Second Hospital of Jilin University, Changchun 130041, China
- Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases, The Second Hospital of Jilin University, Changchun 130041, China
| | - Dan Zhang
- Department of Hepatobiliary and Pancreatic Surgery, The Second Hospital of Jilin University, Changchun 130041, China
- Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases, The Second Hospital of Jilin University, Changchun 130041, China
| | - Jiyao Sheng
- Department of Hepatobiliary and Pancreatic Surgery, The Second Hospital of Jilin University, Changchun 130041, China
- Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases, The Second Hospital of Jilin University, Changchun 130041, China
| | - Xin Wen
- The Second Hospital of Jilin University, Changchun 130041, China
| | - Qingyu Wang
- Department of Orthopedics, The Second Hospital of Jilin University, Changchun 130041, China
| | - Gaoyang Chen
- Department of Orthopedics, The Second Hospital of Jilin University, Changchun 130041, China
| | - Zhaoyan Li
- Department of Orthopedics, The Second Hospital of Jilin University, Changchun 130041, China
| | - Zhenwu Du
- Department of Orthopedics, The Second Hospital of Jilin University, Changchun 130041, China
- Research Center of Second Clinical College, Jilin University, Changchun 130041, China
| | - Xuewen Zhang
- Department of Hepatobiliary and Pancreatic Surgery, The Second Hospital of Jilin University, Changchun 130041, China
- Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases, The Second Hospital of Jilin University, Changchun 130041, China
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204
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He L, Zhu H, Zhou S, Wu T, Wu H, Yang H, Mao H, SekharKathera C, Janardhan A, Edick AM, Zhang A, Hu Z, Pan F, Guo Z. Wnt pathway is involved in 5-FU drug resistance of colorectal cancer cells. Exp Mol Med 2018; 50:1-12. [PMID: 30111797 PMCID: PMC6093888 DOI: 10.1038/s12276-018-0128-8] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Revised: 04/28/2018] [Accepted: 05/01/2018] [Indexed: 11/09/2022] Open
Abstract
Colorectal cancer (CRC) is one of the leading causes of cancer-related death worldwide. 5-Fluorouracil (5-FU) is widely used in the treatment of cancers, but its antineoplastic activity is limited in drug-resistant cancer cells. To investigate the detailed mechanism of 5-FU resistance, we developed a model of 5-FU-resistant cells from HCT-8 cells, a well-established colorectal cancer cell line. We found that the drug-resistant cells demonstrated high expression of TCF4 and β-catenin, indicating an upregulated Wnt pathway. A microarray analysis revealed that the suppression of the checkpoint kinase 1 (CHK1) pathway explained the resistance to 5-FU, especially in p53 wild-type cancer cells such as HCT-8. Our data also demonstrated that the CHK1 pathway is suppressed by the Wnt pathway in 5-FU-resistant cells. In summary, we have discovered a novel mechanism for 5-FU resistance mediated by histone deacetylation, which also revealed the crosstalk between the Wnt pathway and CHK1 pathway.
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Affiliation(s)
- Lingfeng He
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Hong Zhu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Shiying Zhou
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Ting Wu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Huan Wu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Huan Yang
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Huiwen Mao
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Chandra SekharKathera
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Avilala Janardhan
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Ashlin M Edick
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
| | - Anna Zhang
- Department of Psychology, University of Guelph, Guelph, ON, Canada
| | - Zhigang Hu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Feiyan Pan
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China
| | - Zhigang Guo
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, 1 WenYuan Road, Nanjing, 210023, China.
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205
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Targeting acute myeloid leukemia CD34 + stem/progenitor cells with small molecule inhibitor MK-8776. Leuk Res 2018; 72:71-73. [PMID: 30103203 DOI: 10.1016/j.leukres.2018.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 08/04/2018] [Accepted: 08/06/2018] [Indexed: 01/21/2023]
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206
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Mirza-Aghazadeh-Attari M, Darband SG, Kaviani M, Mihanfar A, Aghazadeh Attari J, Yousefi B, Majidinia M. DNA damage response and repair in colorectal cancer: Defects, regulation and therapeutic implications. DNA Repair (Amst) 2018; 69:34-52. [PMID: 30055507 DOI: 10.1016/j.dnarep.2018.07.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/15/2018] [Accepted: 07/15/2018] [Indexed: 12/11/2022]
Abstract
DNA damage response, a key factor involved in maintaining genome integrity and stability, consists of several kinase-dependent signaling pathways, which sense and transduce DNA damage signal. The severity of damage appears to determine DNA damage responses, which can include cell cycle arrest, damage repair and apoptosis. A number of recent studies have demonstrated that defection in signaling through this network is thought to be an underlying mechanism behind the development and progression of various types of human malignancies, including colorectal cancer. In this review, colorectal cancer and its molecular pathology as well as DNA damage response is briefly introduced. Finally, the involvement of key components of this network in the initiation/progression, prognosis, response to treatment and development of drug resistance is comprehensively discussed.
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Affiliation(s)
- Mohammad Mirza-Aghazadeh-Attari
- Aging Research Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saber Ghazizadeh Darband
- Danesh Pey Hadi Co., Health Technology Development Center, Urmia University of Medical Sciences, Urmia, Iran
| | - Mojtaba Kaviani
- School of Nutrition and Dietetics, Acadia University, Wolfville, Nova Scotia, Canada
| | - Ainaz Mihanfar
- Stem Cell and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Bahman Yousefi
- Molecular Medicine Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Maryam Majidinia
- Solid Tumor Research Center, Urmia University of Medical Sciences, Urmia, Iran.
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207
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Hwang BJ, Adhikary G, Eckert RL, Lu AL. Chk1 inhibition as a novel therapeutic strategy in melanoma. Oncotarget 2018; 9:30450-30464. [PMID: 30100999 PMCID: PMC6084399 DOI: 10.18632/oncotarget.25765] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Accepted: 06/28/2018] [Indexed: 12/11/2022] Open
Abstract
Melanoma patients respond poorly to chemotherapies because they acquire drug resistance. Therapies that can overcome the resistance to inhibitors of the mutated BRAF protein kinase in melanoma are urgently needed. Chk1 protein kinase is a central component of the DNA damage response and plays a crucial role in controlling cell cycle progression. Analyses indicate that low mRNA expression of Chk1 is significantly associated with good overall survival of melanoma patients. To evaluate the effectiveness of Chk1 inhibitors in melanoma therapy, we have generated BRAF inhibitor (PLX4032 or vemurafenib) resistant melanoma cell lines (A375-PLX-R and WM9-PLX-R) from A375 and WM9, respectively. We observe that AKT (protein kinase B) is constitutively activated in A375-PLX-R, but not in WM9-PLX-R cells, suggesting that these cells develop resistance to PLX4032 through different mechanisms. We show that a potent and specific inhibitor of Chk1 (PF477736) is effective in reducing cell viability and colony formation of PLX4032-resistant cells. Even more impressively, PF477736 triggers PLX4032-resistant melanoma cells to regain sensitivity to the PLX4032. Mouse xenograft studies show that treating A375-PLX-R derived tumors with combined PLX4032 and PF477736 significantly reduce tumor growth. Combined treatments with PLX4032 and PF477736 reduce the levels of total Chk1 protein and alter Chk1 phosphorylation at several sites in both PLX4032 sensitive and resistant melanoma cells. Combinatorial treatments with PLX4032 and PF477736 to melanoma cells substantially induce DNA damage and cell death. Our results suggest that Chk1 inhibitors may provide new therapy options for melanoma patients.
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Affiliation(s)
- Bor-Jang Hwang
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA.,University of Maryland Greenebaum Comprehensive Cancer Center, Baltimore, MD, USA
| | - Gautam Adhikary
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Richard L Eckert
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA.,University of Maryland Greenebaum Comprehensive Cancer Center, Baltimore, MD, USA.,Department of Dermatology, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Reproductive Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - A-Lien Lu
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA.,University of Maryland Greenebaum Comprehensive Cancer Center, Baltimore, MD, USA
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208
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Lemmens B, Hegarat N, Akopyan K, Sala-Gaston J, Bartek J, Hochegger H, Lindqvist A. DNA Replication Determines Timing of Mitosis by Restricting CDK1 and PLK1 Activation. Mol Cell 2018; 71:117-128.e3. [PMID: 30008317 PMCID: PMC6039720 DOI: 10.1016/j.molcel.2018.05.026] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/27/2018] [Accepted: 05/21/2018] [Indexed: 12/26/2022]
Abstract
To maintain genome stability, cells need to replicate their DNA before dividing. Upon completion of bulk DNA synthesis, the mitotic kinases CDK1 and PLK1 become active and drive entry into mitosis. Here, we have tested the hypothesis that DNA replication determines the timing of mitotic kinase activation. Using an optimized double-degron system, together with kinase inhibitors to enforce tight inhibition of key proteins, we find that human cells unable to initiate DNA replication prematurely enter mitosis. Preventing DNA replication licensing and/or firing causes prompt activation of CDK1 and PLK1 in S phase. In the presence of DNA replication, inhibition of CHK1 and p38 leads to premature activation of mitotic kinases, which induces severe replication stress. Our results demonstrate that, rather than merely a cell cycle output, DNA replication is an integral signaling component that restricts activation of mitotic kinases. DNA replication thus functions as a brake that determines cell cycle duration.
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Affiliation(s)
- Bennie Lemmens
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden; Division of Genome Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet and Science for Life Laboratory, Stockholm, Sweden
| | - Nadia Hegarat
- Genome Damage and Stability Centre, University of Sussex, Brighton, UK
| | - Karen Akopyan
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Joan Sala-Gaston
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Jiri Bartek
- Division of Genome Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet and Science for Life Laboratory, Stockholm, Sweden; Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Helfrid Hochegger
- Genome Damage and Stability Centre, University of Sussex, Brighton, UK.
| | - Arne Lindqvist
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.
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209
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Wang Z, Førsund MS, Trope CG, Nesland JM, Holm R, Slipicevic A. Evaluation of CHK1 activation in vulvar squamous cell carcinoma and its potential as a therapeutic target in vitro. Cancer Med 2018; 7:3955-3964. [PMID: 29963769 PMCID: PMC6089182 DOI: 10.1002/cam4.1638] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/28/2018] [Accepted: 05/28/2018] [Indexed: 11/05/2022] Open
Abstract
CHK1 is an important regulator of the cell cycle and DNA damage response, and its altered expression has been identified in various tumors. Chk1 inhibitors are currently being evaluated as monotherapy and as potentiators of chemotherapy in clinical settings. However, to our knowledge, no previous study has investigated either the activation status or the therapeutic potential of CHK1 targeting in vulvar cancer. Therefore, we examined the expression status of activated CHK1 forms pCHK1Ser345, pCHK1Ser317, pCHK1Ser296, and pCHK1Ser280 in 294 vulvar squamous cell carcinomas (VSCC) using immunohistochemistry and analyzed their relationships with various clinicopathological variables and clinical outcome. To aid translation of preclinical studies, we also assessed cell sensitivity to the Chk1 inhibition in two vulvar cancer cell lines. Compared to the levels of pCHK1Ser345, pCHK1Ser317, pCHK1Ser296, and pCHK1Ser280 in normal vulvar squamous epithelium, high nuclear pCHK1Ser345 expression was found in 57% of vulvar carcinomas, whereas low nuclear pCHK1Ser317, pCHK1Ser296, and pCHK1Ser280 expressions were observed in 58%, 64%, and 40% of the cases, respectively. Low levels of pCHK1Ser317 and pCHK1Ser280 in the nucleus correlated significantly with advanced tumor behaviors and aggressive features. None of pCHK1Ser345, pCHK1Ser317, pCHK1Ser296, and pCHK1Ser280 forms were identified as prognostic factors. In vitro inhibition of CHK1 by small molecular inhibitors or siRNA reduced viability by inducing DNA damage and apoptosis of vulvar cancer cell lines. In summary, we conclude that cellular functions regulated by CHK1 are phosphorylation/localization‐dependent and deregulation of CHK1 function occurs in VSCC and might contribute to tumorigenesis. Targeting CHK1 might represent as a useful antitumor strategy for the subgroup of VSCC harboring p53 mutations.
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Affiliation(s)
- Zhihui Wang
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Mette S Førsund
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Claes G Trope
- Department of Obstetrics and Gynecology, The Norwegian Radium Hospital, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Jahn M Nesland
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Ruth Holm
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Ana Slipicevic
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
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210
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Desai A, Yan Y, Gerson SL. Advances in therapeutic targeting of the DNA damage response in cancer. DNA Repair (Amst) 2018; 66-67:24-29. [PMID: 29715575 PMCID: PMC6005187 DOI: 10.1016/j.dnarep.2018.04.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 04/21/2018] [Indexed: 01/13/2023]
Abstract
The DNA damage response (DDR) is a series of pathways and processes required to repair lesions to DNA. These pathways range from repairing strand breaks to the double helix, damaged bases formed after oxidation or deamination, inaccurate DNA replication resulting in mispaired base alignment, intrastrand crosslinks that trigger cell death, and a plethora of other genomic insults. The DDR is believed to be a critical component of radio and chemoresistance in many cancers as well, with the tumor's ability to repair therapy induced damage being an important tool used to survive traditional chemotherapeutic agents. Here we summarize advances made in specifically targeting DDR proteins in cancer therapy and project on the potential breakthroughs and pitfalls to arise as the field progresses.
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Affiliation(s)
- Amar Desai
- Department of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA; Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Yan Yan
- Department of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA; Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Stanton L Gerson
- Department of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA; Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA.
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211
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Roy S, Roy S, Rana A, Akhter Y, Hande MP, Banerjee B. The role of p38 MAPK pathway in p53 compromised state and telomere mediated DNA damage response. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2018; 836:89-97. [PMID: 30389168 DOI: 10.1016/j.mrgentox.2018.05.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 04/17/2018] [Accepted: 05/26/2018] [Indexed: 12/19/2022]
Abstract
There is an intricate balance of DNA damage response and repair which determines the homeostasis of human genome function. p53 protein is widely known for its role in cell cycle regulation and tumor suppressor activity. In case of several cancers where function of p53 gene gets compromised either by mutation or partial inactivation, the role of p53 in response to DNA damage needs to be supplemented by another molecule or pathway. Due to sedentary lifestyle and exposure to genotoxic agents, genome is predisposed to chronic stress, which ultimately leads to unrepaired or background DNA damage. p38 MAPK signaling pathway is strongly activated in response to various environmental and cellular stresses. DNA damage response and the repair options have crucial links with chromosomal integrity. Telomere that regulates integrity of genome is protected by a six member shielding unit called shelterin complex which communicates with other pathways for functionality of telomeres. There are evidences that p38 gets activated through ATM in response to DNA damage. Dysfunctional telomere leads to activation of ATM which subsequently activates p38 suggesting a crosstalk between p38, ATM and shelterin complex. This review focuses on activation of p38 in response to genotoxic stress induced DNA damage in p53 mutated or compromised state and its possible cross talk with telomere shelterin proteins. Thus p38 may act as an important target to treat various diseases and in majority of cancers in p53 mutated state.
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Affiliation(s)
- Shomereeta Roy
- Molecular Stress and Stem Cell Biology Group, School of Biotechnology, KIIT University, Bhubaneswar, Odisha-751024, India
| | - Souvick Roy
- Molecular Stress and Stem Cell Biology Group, School of Biotechnology, KIIT University, Bhubaneswar, Odisha-751024, India
| | - Aarti Rana
- Centre for Computational Biology and Bioinformatics, School of Life Sciences, Central University of Himachal Pradesh, Shahpur, Himachal Pradesh-176206, India
| | - Yusuf Akhter
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Vidya Vihar, Raebareli Road, Lucknow, Uttar Pradesh 226025, India
| | - Manoor Prakash Hande
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593, Singapore
| | - Birendranath Banerjee
- Molecular Stress and Stem Cell Biology Group, School of Biotechnology, KIIT University, Bhubaneswar, Odisha-751024, India.
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212
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Bai M, Song N, Che X, Wang X, Qu X, Liu Y. Chk1 activation attenuates sensitivity of lapatinib in HER2-positive gastric cancer. Cell Biol Int 2018; 42:781-793. [PMID: 29271513 DOI: 10.1002/cbin.10922] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 12/17/2017] [Indexed: 12/16/2022]
Affiliation(s)
- Ming Bai
- Department of Medical Oncology; The First Hospital of China Medical University; Shenyang 110001 China
- Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province; The First Hospital of China Medical University; Shenyang 110001 China
| | - Na Song
- Department of Medical Oncology; The First Hospital of China Medical University; Shenyang 110001 China
- Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province; The First Hospital of China Medical University; Shenyang 110001 China
| | - Xiaofang Che
- Department of Medical Oncology; The First Hospital of China Medical University; Shenyang 110001 China
- Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province; The First Hospital of China Medical University; Shenyang 110001 China
| | - Xiaoxun Wang
- Department of Medical Oncology; The First Hospital of China Medical University; Shenyang 110001 China
- Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province; The First Hospital of China Medical University; Shenyang 110001 China
| | - Xiujuan Qu
- Department of Medical Oncology; The First Hospital of China Medical University; Shenyang 110001 China
- Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province; The First Hospital of China Medical University; Shenyang 110001 China
| | - Yunpeng Liu
- Department of Medical Oncology; The First Hospital of China Medical University; Shenyang 110001 China
- Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province; The First Hospital of China Medical University; Shenyang 110001 China
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213
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Manic G, Signore M, Sistigu A, Russo G, Corradi F, Siteni S, Musella M, Vitale S, De Angelis ML, Pallocca M, Amoreo CA, Sperati F, Di Franco S, Barresi S, Policicchio E, De Luca G, De Nicola F, Mottolese M, Zeuner A, Fanciulli M, Stassi G, Maugeri-Saccà M, Baiocchi M, Tartaglia M, Vitale I, De Maria R. CHK1-targeted therapy to deplete DNA replication-stressed, p53-deficient, hyperdiploid colorectal cancer stem cells. Gut 2018; 67:903-917. [PMID: 28389531 PMCID: PMC5890648 DOI: 10.1136/gutjnl-2016-312623] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 02/03/2017] [Accepted: 02/28/2017] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Cancer stem cells (CSCs) are responsible for tumour formation and spreading, and their targeting is required for tumour eradication. There are limited therapeutic options for advanced colorectal cancer (CRC), particularly for tumours carrying RAS-activating mutations. The aim of this study was to identify novel CSC-targeting strategies. DESIGN To discover potential therapeutics to be clinically investigated as single agent, we performed a screening with a panel of FDA-approved or investigational drugs on primary CRC cells enriched for CSCs (CRC-SCs) isolated from 27 patients. Candidate predictive biomarkers of efficacy were identified by integrating genomic, reverse-phase protein microarray (RPPA) and cytogenetic analyses, and validated by immunostainings. DNA replication stress (RS) was increased by employing DNA replication-perturbing or polyploidising agents. RESULTS The drug-library screening led to the identification of LY2606368 as a potent anti-CSC agent acting in vitro and in vivo in tumour cells from a considerable number of patients (∼36%). By inhibiting checkpoint kinase (CHK)1, LY2606368 affected DNA replication in most CRC-SCs, including RAS-mutated ones, forcing them into premature, lethal mitoses. Parallel genomic, RPPA and cytogenetic analyses indicated that CRC-SCs sensitive to LY2606368 displayed signs of ongoing RS response, including the phosphorylation of RPA32 and ataxia telangiectasia mutated serine/threonine kinase (ATM). This was associated with mutation(s) in TP53 and hyperdiploidy, and made these CRC-SCs exquisitely dependent on CHK1 function. Accordingly, experimental increase of RS sensitised resistant CRC-SCs to LY2606368. CONCLUSIONS LY2606368 selectively eliminates replication-stressed, p53-deficient and hyperdiploid CRC-SCs independently of RAS mutational status. These results provide a strong rationale for biomarker-driven clinical trials with LY2606368 in patients with CRC.
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Affiliation(s)
- Gwenola Manic
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Michele Signore
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Antonella Sistigu
- Department of Research, Advanced Diagnostics and Technological Innovation, Regina Elena National Cancer Institute, Rome, Italy
| | - Giorgio Russo
- Department of Research, Advanced Diagnostics and Technological Innovation, Regina Elena National Cancer Institute, Rome, Italy,Institute of General Pathology, Catholic University and A. Gemelli Polyclinic, Rome, Italy
| | - Francesca Corradi
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Silvia Siteni
- Department of Research, Advanced Diagnostics and Technological Innovation, Regina Elena National Cancer Institute, Rome, Italy,Department of Science, University “Roma Tre”, Rome, Italy
| | - Martina Musella
- Department of Research, Advanced Diagnostics and Technological Innovation, Regina Elena National Cancer Institute, Rome, Italy,Department of Molecular Medicine, University “La Sapienza”, Rome, Italy
| | - Sara Vitale
- Institute of General Pathology, Catholic University and A. Gemelli Polyclinic, Rome, Italy
| | - Maria Laura De Angelis
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Matteo Pallocca
- SAFU, Department of Research, Advanced Diagnostics, and Technological Innovation, Translational Research Area, Regina Elena National Cancer Institute, RomeItaly
| | | | - Francesca Sperati
- Biostatistical Unit, Regina Elena National Cancer Institute, Rome, Italy
| | - Simone Di Franco
- Department of Surgical Oncological and Stomatological Sciences, University of Palermo, Palermo, Italy
| | - Sabina Barresi
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico “Bambino Gesù”, Rome, Italy
| | - Eleonora Policicchio
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy,Department of Experimental Medicine, University “La Sapienza”, Rome, Italy
| | - Gabriele De Luca
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Francesca De Nicola
- SAFU, Department of Research, Advanced Diagnostics, and Technological Innovation, Translational Research Area, Regina Elena National Cancer Institute, RomeItaly
| | - Marcella Mottolese
- Department of Pathology, Regina Elena National Cancer Institute, Rome, Italy
| | - Ann Zeuner
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Maurizio Fanciulli
- SAFU, Department of Research, Advanced Diagnostics, and Technological Innovation, Translational Research Area, Regina Elena National Cancer Institute, RomeItaly
| | - Giorgio Stassi
- Department of Surgical Oncological and Stomatological Sciences, University of Palermo, Palermo, Italy
| | | | - Marta Baiocchi
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico “Bambino Gesù”, Rome, Italy
| | - Ilio Vitale
- Department of Biology, University of Rome “Tor Vergata”, Rome, Italy,Department of Research, Advanced Diagnostics and Technological Innovation, Regina Elena National Cancer Institute, Rome, Italy
| | - Ruggero De Maria
- Institute of General Pathology, Catholic University and A. Gemelli Polyclinic, Rome, Italy
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214
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Meng Y, Chen CW, Yung MMH, Sun W, Sun J, Li Z, Li J, Li Z, Zhou W, Liu SS, Cheung ANY, Ngan HYS, Braisted JC, Kai Y, Peng W, Tzatsos A, Li Y, Dai Z, Zheng W, Chan DW, Zhu W. DUOXA1-mediated ROS production promotes cisplatin resistance by activating ATR-Chk1 pathway in ovarian cancer. Cancer Lett 2018; 428:104-116. [PMID: 29704517 DOI: 10.1016/j.canlet.2018.04.029] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 04/18/2018] [Accepted: 04/20/2018] [Indexed: 01/16/2023]
Abstract
The acquisition of resistance is a major obstacle to the clinical use of platinum drugs for ovarian cancer treatment. Increase of DNA damage response is one of major mechanisms contributing to platinum-resistance. However, how DNA damage response is regulated in platinum-resistant ovarian cancer cells remains unclear. Using quantitative high throughput combinational screen (qHTCS) and RNA-sequencing (RNA-seq), we show that dual oxidase maturation factor 1 (DUOXA1) is overexpressed in platinum-resistant ovarian cancer cells, resulting in over production of reactive oxygen species (ROS). Elevated ROS level sustains the activation of ATR-Chk1 pathway, leading to resistance to cisplatin in ovarian cancer cells. Moreover, using qHTCS we identified two Chk1 inhibitors (PF-477736 and AZD7762) that re-sensitize resistant cells to cisplatin. Blocking this novel pathway by inhibiting ROS, DUOXA1, ATR or Chk1 effectively overcomes cisplatin resistance in vitro and in vivo. Significantly, the clinical studies also confirm the activation of ATR and DOUXA1 in ovarian cancer patients, and elevated DOUXA1 or ATR-Chk1 pathway correlates with poor prognosis. Taken together, our findings not only reveal a novel mechanism regulating cisplatin resistance, but also provide multiple combinational strategies to overcome platinum-resistance in ovarian cancer.
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Affiliation(s)
- Yunxiao Meng
- Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA; GW Cancer Center, The George Washington University, Washington, DC, 20052, USA
| | - Chi-Wei Chen
- Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA; GW Cancer Center, The George Washington University, Washington, DC, 20052, USA
| | - Mingo M H Yung
- Department of Obstetrics and Gynecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Wei Sun
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jing Sun
- Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA; GW Cancer Center, The George Washington University, Washington, DC, 20052, USA
| | - Zhuqing Li
- Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA; GW Cancer Center, The George Washington University, Washington, DC, 20052, USA
| | - Jing Li
- Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA; GW Cancer Center, The George Washington University, Washington, DC, 20052, USA
| | - Zongzhu Li
- Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA; GW Cancer Center, The George Washington University, Washington, DC, 20052, USA
| | - Wei Zhou
- Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA; GW Cancer Center, The George Washington University, Washington, DC, 20052, USA; Department of Colorectal Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
| | - Stephanie S Liu
- Department of Obstetrics and Gynecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Annie N Y Cheung
- Department of Pathology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Hextan Y S Ngan
- Department of Obstetrics and Gynecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - John C Braisted
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Yan Kai
- GW Cancer Center, The George Washington University, Washington, DC, 20052, USA; Department of Physics, The George Washington University Columbian College of Arts & Sciences, Washington, DC, 20052, USA
| | - Weiqun Peng
- Department of Physics, The George Washington University Columbian College of Arts & Sciences, Washington, DC, 20052, USA
| | - Alexandros Tzatsos
- GW Cancer Center, The George Washington University, Washington, DC, 20052, USA; Department of Anatomy and Regenerative Biology, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA
| | - Yiliang Li
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Peking Union Medical College & Chinese Academy of Medical Sciences, Tianjin, 300192, China
| | - Zhijun Dai
- Department of Oncology, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an, 710004, China
| | - Wei Zheng
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - David W Chan
- Department of Obstetrics and Gynecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.
| | - Wenge Zhu
- Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20037, USA; GW Cancer Center, The George Washington University, Washington, DC, 20052, USA.
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215
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Abbas HHK, Alhamoudi KMH, Evans MD, Jones GDD, Foster SS. MTH1 deficiency selectively increases non-cytotoxic oxidative DNA damage in lung cancer cells: more bad news than good? BMC Cancer 2018; 18:423. [PMID: 29661172 PMCID: PMC5903006 DOI: 10.1186/s12885-018-4332-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 04/04/2018] [Indexed: 12/18/2022] Open
Abstract
Background Targeted therapies are based on exploiting cancer-cell-specific genetic features or phenotypic traits to selectively kill cancer cells while leaving normal cells unaffected. Oxidative stress is a cancer hallmark phenotype. Given that free nucleotide pools are particularly vulnerable to oxidation, the nucleotide pool sanitising enzyme, MTH1, is potentially conditionally essential in cancer cells. However, findings from previous MTH1 studies have been contradictory, meaning the relevance of MTH1 in cancer is still to be determined. Here we ascertained the role of MTH1 specifically in lung cancer cell maintenance, and the potential of MTH1 inhibition as a targeted therapy strategy to improve lung cancer treatments. Methods Using siRNA-mediated knockdown or small-molecule inhibition, we tested the genotoxic and cytotoxic effects of MTH1 deficiency on H23 (p53-mutated), H522 (p53-mutated) and A549 (wildtype p53) non-small cell lung cancer cell lines relative to normal MRC-5 lung fibroblasts. We also assessed if MTH1 inhibition augments current therapies. Results MTH1 knockdown increased levels of oxidatively damaged DNA and DNA damage signaling alterations in all lung cancer cell lines but not normal fibroblasts, despite no detectable differences in reactive oxygen species levels between any cell lines. Furthermore, MTH1 knockdown reduced H23 cell proliferation. However, unexpectedly, it did not induce apoptosis in any cell line or enhance the effects of gemcitabine, cisplatin or radiation in combination treatments. Contrastingly, TH287 and TH588 MTH1 inhibitors induced apoptosis in H23 and H522 cells, but only increased oxidative DNA damage levels in H23, indicating that they kill cells independently of DNA oxidation and seemingly via MTH1-distinct mechanisms. Conclusions MTH1 has a NSCLC-specific p53-independent role for suppressing DNA oxidation and genomic instability, though surprisingly the basis of this may not be reactive-oxygen-species-associated oxidative stress. Despite this, overall our cell viability data indicates that targeting MTH1 will likely not be an across-the-board effective NSCLC therapeutic strategy; rather it induces non-cytotoxic DNA damage that could promote cancer heterogeneity and evolution. Electronic supplementary material The online version of this article (10.1186/s12885-018-4332-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hussein H K Abbas
- Department of Genetics and Genome Biology, University of Leicester, Leicester, Leicestershire, LE1 7RH, UK.,Department of Pathology and Forensic Medicine, College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
| | - Kheloud M H Alhamoudi
- Department of Genetics and Genome Biology, University of Leicester, Leicester, Leicestershire, LE1 7RH, UK
| | - Mark D Evans
- Faculty of Health and Life Sciences, De Montfort University, Leicester, Leicestershire, LE1 9BH, UK
| | - George D D Jones
- Department of Genetics and Genome Biology, University of Leicester, Leicester, Leicestershire, LE1 7RH, UK.
| | - Steven S Foster
- Department of Genetics and Genome Biology, University of Leicester, Leicester, Leicestershire, LE1 7RH, UK.
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216
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Yu X, Zhang Y, Ma X, Pertsemlidis A. miR-195 potentiates the efficacy of microtubule-targeting agents in non-small cell lung cancer. Cancer Lett 2018; 427:85-93. [PMID: 29656007 DOI: 10.1016/j.canlet.2018.04.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 03/30/2018] [Accepted: 04/07/2018] [Indexed: 12/14/2022]
Abstract
Microtubule-targeting agents (MTAs) are widely used for the treatment of non-small cell lung cancer (NSCLC). The response rate is only ∼25%, mainly attributable to drug resistance. To identify determinants of resistance in NSCLC, we performed a high-throughput screen using a library of miRNA mimics. Here we report that miR-195 synergizes with MTAs to inhibit the growth of NSCLC cells in vitro, that increased expression of miR-195 sensitizes NSCLC cells to MTAs and that repression of miR-195 confers resistance to MTAs. We show that NSCLC tumors over-expressing miR-195 are more sensitive to MTA treatment and that induced expression of miR-195 in NSCLC tumors potentiates the anti-tumor effect of MTAs. Additionally, we demonstrate that miR-195 targets checkpoint kinase 1 (CHEK1) to regulate the response of NSCLC cells to MTAs, that over-expression of CHEK1 contributes to resistance to MTAs and that knock-down of CHEK1 synergizes with MTAs to repress cell growth. Our results highlight the importance of miR-195 in regulating the response of NSCLC cells to MTAs and underline the potential application of miR-195 as a biomarker for response to MTAs, and as a therapeutic adjuvant to MTA treatment.
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Affiliation(s)
- Xiaojie Yu
- Greehey Children's Cancer Research Institute, The University of Texas Health Science Center at San Antonio, TX, 78229, USA; Department of Cell Systems and Anatomy, The University of Texas Health Science Center at San Antonio, TX, 78229, USA
| | - Yiqiang Zhang
- Greehey Children's Cancer Research Institute, The University of Texas Health Science Center at San Antonio, TX, 78229, USA
| | - Xiuye Ma
- Greehey Children's Cancer Research Institute, The University of Texas Health Science Center at San Antonio, TX, 78229, USA
| | - Alexander Pertsemlidis
- Greehey Children's Cancer Research Institute, The University of Texas Health Science Center at San Antonio, TX, 78229, USA; Department of Cell Systems and Anatomy, The University of Texas Health Science Center at San Antonio, TX, 78229, USA; Department of Pediatrics, The University of Texas Health Science Center at San Antonio, TX, 78229, USA.
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217
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Massey AJ. A high content, high throughput cellular thermal stability assay for measuring drug-target engagement in living cells. PLoS One 2018; 13:e0195050. [PMID: 29617433 PMCID: PMC5884524 DOI: 10.1371/journal.pone.0195050] [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: 01/03/2018] [Accepted: 03/15/2018] [Indexed: 01/08/2023] Open
Abstract
Determining and understanding drug target engagement is critical for drug discovery. This can be challenging within living cells as selective readouts are often unavailable. Here we describe a novel method for measuring target engagement in living cells based on the principle of altered protein thermal stabilization / destabilization in response to ligand binding. This assay (HCIF-CETSA) utilizes high content, high throughput single cell immunofluorescent detection to determine target protein levels following heating of adherent cells in a 96 well plate format. We have used target engagement of Chk1 by potent small molecule inhibitors to validate the assay. Target engagement measured by this method was subsequently compared to target engagement measured by two alternative methods (autophosphorylation and CETSA). The HCIF-CETSA method appeared robust and a good correlation in target engagement measured by this method and CETSA for the selective Chk1 inhibitor V158411 was observed. However, these EC50 values were 23- and 12-fold greater than the autophosphorylation IC50. The described method is therefore a valuable advance in the CETSA method allowing the high throughput determination of target engagement in adherent cells.
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218
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Turcotte CA, Sloat SA, Rigothi JA, Rosenkranse E, Northrup AL, Andrews NP, Checchi PM. Maintenance of Genome Integrity by Mi2 Homologs CHD-3 and LET-418 in Caenorhabditis elegans. Genetics 2018; 208:991-1007. [PMID: 29339410 PMCID: PMC5844346 DOI: 10.1534/genetics.118.300686] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 01/10/2018] [Indexed: 02/06/2023] Open
Abstract
Meiotic recombination depends upon the tightly coordinated regulation of chromosome dynamics and is essential for the production of haploid gametes. Central to this process is the formation and repair of meiotic double-stranded breaks (DSBs), which must take place within the constraints of a specialized chromatin architecture. Here, we demonstrate a role for the nucleosome remodeling and deacetylase (NuRD) complex in orchestrating meiotic chromosome dynamics in Caenorhabditis elegans Our data reveal that the conserved Mi2 homologs Chromodomain helicase DNA-binding protein (CHD-3) and its paralog LET-418 facilitate meiotic progression by ensuring faithful repair of DSBs through homologous recombination. We discovered that loss of either CHD-3 or LET-418 results in elevated p53-dependent germ line apoptosis, which relies on the activation of the conserved checkpoint kinase CHK-1 Consistent with these findings, chd-3 and let-418 mutants produce a reduced number of offspring, indicating a role for Mi2 in forming viable gametes. When Mi2 function is compromised, persisting recombination intermediates are detected in late pachytene nuclei, indicating a failure in the timely repair of DSBs. Intriguingly, our data indicate that in Mi2 mutant germ lines, a subset of DSBs are repaired by nonhomologous end joining, which manifests as chromosomal fusions. We find that meiotic defects are exacerbated in Mi2 mutants lacking CKU-80, as evidenced by increased recombination intermediates, corpses, and defects in chromosomal integrity. Taken together, our findings support a model wherein the C. elegans Mi2 complex maintains genomic integrity through reinforcement of a chromatin landscape suitable for homology-driven repair mechanisms.
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Affiliation(s)
| | - Solomon A Sloat
- Department of Biology, Marist College, Poughkeepsie, New York 12601
| | - Julia A Rigothi
- Department of Biology, Marist College, Poughkeepsie, New York 12601
| | | | | | | | - Paula M Checchi
- Department of Biology, Marist College, Poughkeepsie, New York 12601
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219
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Geng X, Ren Y, Wang F, Tian D, Yao X, Zhang Y, Tang J. Harmines inhibit cancer cell growth through coordinated activation of apoptosis and inhibition of autophagy. Biochem Biophys Res Commun 2018; 498:99-104. [PMID: 29501493 DOI: 10.1016/j.bbrc.2018.02.205] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 02/28/2018] [Indexed: 12/27/2022]
Abstract
Harmine and its analogs have long been considered as anticancer agents. In vitro analyses suggested that intercalating DNA or inhibiting topoisomerase might contribute to the cytotoxic effect of this class of compound. However, this idea has not been rigorously tested in intact cells. By synthesizing novel derivatives, here we demonstrate that harmines did not activate the DNA damage response, a cellular signaling commonly induced by agents that intercalate DNA or inhibit topoisomerase. These findings suggest that mechanisms other than DNA intercalating or topoisomerase inhibiting contribute to the toxicity of harmines in vivo. Using a novel N2-benzyl and N9-arylated alkyl compound 10f that has good solubility and stability as the model, we show that harmines strongly inhibited the growth of cancer cells originated from breast, lung, bone and pancreas, but not that of normal fibroblasts. We further show that 10f induced apoptosis and inhibited autophagy in a dose and time-dependent manner. An apoptosis inhibitor suppressed 10f-induced cell death. Together, our results reveal previously unidentified insights into the anticancer mechanism of harmines, supporting future development of this compound class in the treatment of human cancers.
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Affiliation(s)
- Xinran Geng
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, People's Republic of China; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drug Research, Jinan University, Guangzhou 510632, People's Republic of China
| | - Yichang Ren
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, People's Republic of China; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drug Research, Jinan University, Guangzhou 510632, People's Republic of China
| | - Fangfang Wang
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, People's Republic of China; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drug Research, Jinan University, Guangzhou 510632, People's Republic of China
| | - Danmei Tian
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, People's Republic of China; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drug Research, Jinan University, Guangzhou 510632, People's Republic of China
| | - Xinsheng Yao
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, People's Republic of China; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drug Research, Jinan University, Guangzhou 510632, People's Republic of China
| | - Youwei Zhang
- Department of Pharmacology, Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
| | - Jinshan Tang
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, People's Republic of China; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drug Research, Jinan University, Guangzhou 510632, People's Republic of China.
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220
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Li QQ, Hsu I, Sanford T, Railkar R, Balaji N, Sourbier C, Vocke C, Balaji KC, Agarwal PK. Protein kinase D inhibitor CRT0066101 suppresses bladder cancer growth in vitro and xenografts via blockade of the cell cycle at G2/M. Cell Mol Life Sci 2018; 75:939-963. [PMID: 29071385 PMCID: PMC7984729 DOI: 10.1007/s00018-017-2681-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Revised: 09/05/2017] [Accepted: 10/05/2017] [Indexed: 12/30/2022]
Abstract
The protein kinase D (PKD) family of proteins are important regulators of tumor growth, development, and progression. CRT0066101, an inhibitor of PKD, has antitumor activity in multiple types of carcinomas. However, the effect and mechanism of CRT0066101 in bladder cancer are not understood. In the present study, we show that CRT0066101 suppressed the proliferation and migration of four bladder cancer cell lines in vitro. We also demonstrate that CRT0066101 blocked tumor growth in a mouse flank xenograft model of bladder cancer. To further assess the role of PKD in bladder carcinoma, we examined the three PKD isoforms and found that PKD2 was highly expressed in eight bladder cancer cell lines and in urothelial carcinoma tissues from the TCGA database, and that short hairpin RNA (shRNA)-mediated knockdown of PKD2 dramatically reduced bladder cancer growth and invasion in vitro and in vivo, suggesting that the effect of the compound in bladder cancer is mediated through inhibition of PKD2. This notion was corroborated by demonstrating that the levels of phospho-PKD2 were markedly decreased in CRT0066101-treated bladder tumor explants. Furthermore, our cell cycle analysis by flow cytometry revealed that CRT0066101 treatment or PKD2 silencing arrested bladder cancer cells at the G2/M phase, the arrest being accompanied by decreases in the levels of cyclin B1, CDK1 and phospho-CDK1 (Thr161) and increases in the levels of p27Kip1 and phospho-CDK1 (Thr14/Tyr15). Moreover, CRT0066101 downregulated the expression of Cdc25C, which dephosphorylates/activates CDK1, but enhanced the activity of the checkpoint kinase Chk1, which inhibits CDK1 by phosphorylating/inactivating Cdc25C. Finally, CRT0066101 was found to elevate the levels of Myt1, Wee1, phospho-Cdc25C (Ser216), Gadd45α, and 14-3-3 proteins, all of which reduce the CDK1-cyclin B1 complex activity. These novel findings suggest that CRT0066101 suppresses bladder cancer growth by inhibiting PKD2 through induction of G2/M cell cycle arrest, leading to the blockade of cell cycle progression.
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Affiliation(s)
- Qingdi Quentin Li
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Iawen Hsu
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Thomas Sanford
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Reema Railkar
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Navin Balaji
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Carole Sourbier
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Cathy Vocke
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - K C Balaji
- Wake Forest University School of Medicine, Winston Salem, NC, 27106, USA
| | - Piyush K Agarwal
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
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221
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Wang P, Shan L, Xue L, Zheng B, Ying J, Lu N. Genome wide copy number analyses of superficial esophageal squamous cell carcinoma with and without metastasis. Oncotarget 2018; 8:5069-5080. [PMID: 27974698 PMCID: PMC5354893 DOI: 10.18632/oncotarget.13847] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 11/21/2016] [Indexed: 01/08/2023] Open
Abstract
Superficial esophageal squamous cell carcinoma (ESCC) is generally considered a subtype of less invasive ESCC. Yet a subset of these superficial ESCC would have metastasis after esophagostomy or endoscopic resection and lead to poor prognosis. The objective of this study is to determine biomarkers that can identify such subset of superficial ESCC that would have metastasis after surgery using genome wide copy number alteration (CNA) analyses. The CNAs of 38 cases of superficial ESCCs originated from radical surgery, including 19 without metastasis and 19 with metastasis within 5 years’ post-surgery, were analyzed using Affymetrix OncoScan™ FFPE Assay. A 39-gene signature was identified which characterized the subset of superficial ESCC with high risk of metastasis after surgery. In addition, recurrent CNAs of superficial ESCC were also investigated in the study. Amplification of 11q13.3 (FGF4) and deletion of 9p21.3 (CDKN2A) were found to be recurrent in all 38 superficial ESCCs analyzed. Notably amplifications of 3p26.33 (SOX2OT), 8q24.21 (MYC), 14q21.1 (FOXA1) and deletion of 3p12.1 (GBE1) were only found to be recurrent in metastaic superficial ESCCs. In conclusion, using CNAs analyses, we identify a 39-gene signature which characterizes the high risk metastatic superficial ESCCs and discover several recurrent CNAs that might be the driver alterations in metastasis among superficial ESCCs.
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Affiliation(s)
- Pengjiao Wang
- Department of Pathology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China
| | - Ling Shan
- Department of Pathology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China
| | - Liyan Xue
- Department of Pathology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China
| | - Bo Zheng
- Department of Pathology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China
| | - Jianming Ying
- Department of Pathology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China
| | - Ning Lu
- Department of Pathology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China
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Wayne J, Brooks T, Massey AJ. Inhibition of Chk1 with the small molecule inhibitor V158411 induces DNA damage and cell death in an unperturbed S-phase. Oncotarget 2018; 7:85033-85048. [PMID: 27829224 PMCID: PMC5356717 DOI: 10.18632/oncotarget.13119] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 10/22/2016] [Indexed: 12/30/2022] Open
Abstract
Chk1 kinase is a critical component of the DNA damage response checkpoint and Chk1 inhibitors are currently under clinical investigation. Chk1 suppresses oncogene-induced replication stress with Chk1 inhibitors demonstrating activity as a monotherapy in numerous cancer types. Understanding the mechanism by which Chk1 inhibitors induce DNA damage and cancer cell death is essential for their future clinical development. Here we characterize the mechanism by which the novel Chk1 inhibitor (V158411) increased DNA damage and cell death in models of human cancer. V158411 induced a time- and concentration-dependent increase in γH2AX-positive nuclei that was restricted to cells actively undergoing DNA synthesis. γH2AX induction was an early event and correlated with activation of the ATR/ATM/DNA-PKcs DNA damage response pathways. The appearance of γH2AX positive nuclei preceded ssDNA appearance and RPA exhaustion. Complete and sustained inhibition of Chk1 kinase was necessary to activate a robust γH2AX induction and growth inhibition. Chk1 inhibitor cytotoxicity correlated with induction of DNA damage with cells undergoing apoptosis, mitotic slippage and DNA damage-induced permanent cell cycle arrest. We identified two distinct classes of Chk1 inhibitors: those that induced a strong increase in γH2AX, pChk1 (S317) and pRPA32 (S4/S8) (including V158411, LY2603618 and ARRY-1A) and those that did not (including MK-8776 and GNE-900). Tumor cell death, induced through increased DNA damage, coupled with abrogation of cell cycle checkpoints makes selective inhibitors of Chk1 a potentially useful therapeutic treatment for multiple human cancers.
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223
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Li HX, Zheng JH, Ji L, Liu GY, Lv YK, Yang D, Hu Z, Chen H, Zhang FM, Cao W. Effects of low-intensity ultrasound combined with low-dose carboplatin in an orthotopic hamster model of tongue cancer: A preclinical study. Oncol Rep 2018; 39:1609-1618. [PMID: 29436690 PMCID: PMC5868397 DOI: 10.3892/or.2018.6262] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 02/06/2018] [Indexed: 12/17/2022] Open
Abstract
Low-intensity ultrasound (LIUS) combined with chemotherapy is an innovative modality for cancer treatment, but its effect on orthotopic carcinoma remains unknown. Our previous study revealed that LIUS enhanced the growth inhibitory effects of several chemotherapeutic drugs in nude mice with transplanted tumors. In the present study, we used 7,12-dimethylbenz(alpha)anthracene to induce orthotopic tongue carcinogenesis in hamsters. We used the first-line chemotherapy drug for tongue cancer, carboplatin (CBP) in combination with LIUS to investigate the synergistic effect. The results revealed that LIUS combined with low-dose CBP enhanced the inhibitory effects of CBP on tumor growth, prolonged survival, and did not increase the incidence of side-effects. It also enhanced the inherent DNA damage caused by CBP, suppressed the expression of the DNA repair proteins O6-methylguanine DNA methyltransferase (MGMT) and Chk1, and increased the expression of DNA damage-inducible protein GADD45α. Furthermore, compared with CBP alone, LIUS combined with CBP reduced the expression of cyclin D1 and cyclin B1, induced the expression of caspase-3, cleaved caspase-3, caspase-8, Bax, and Bak, and inhibited the expression of Bcl-2. Examination of clinical samples revealed that MGMT, Chk1, and Gadd45α were higher in OTSCC than in adjacent normal tissue. Hence, our results indicated that LIUS enhanced the ability of low-dose CBP to damage DNA in an orthotopic hamster model of tongue cancer, induced apoptosis, inhibited tumor growth and progression, while it did not increase the toxic side-effects of the drug, suggesting additional clinical benefits for patients treated with the combination of CBP with LIUS.
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Affiliation(s)
- Hai-Xia Li
- Department of Forensic Medicine, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Jin-Hua Zheng
- Department of Anatomy, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Liang Ji
- Department of Anatomy, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Guan-Yao Liu
- Department of Anatomy, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Yv-Kun Lv
- Department of Anatomy, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Dan Yang
- Department of Forensic Medicine, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Zheng Hu
- Laboratory of Sono- and Phototheranostic Technologies, Harbin Institute of Technology, Harbin, Heilongjiang 150080, P.R. China
| | - He Chen
- Department of Forensic Medicine, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Feng-Min Zhang
- Department of Microbiology, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Wenwu Cao
- Laboratory of Sono- and Phototheranostic Technologies, Harbin Institute of Technology, Harbin, Heilongjiang 150080, P.R. China
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MK-8776, a novel chk1 kinase inhibitor, radiosensitizes p53-defective human tumor cells. Oncotarget 2018; 7:71660-71672. [PMID: 27690219 PMCID: PMC5342109 DOI: 10.18632/oncotarget.12311] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 09/20/2016] [Indexed: 12/20/2022] Open
Abstract
Radiotherapy is commonly used to treat a variety of solid tumors but improvements in the therapeutic ratio are sorely needed. The aim of this study was to assess the Chk1 kinase inhibitor, MK-8776, for its ability to radiosensitize human tumor cells. Cells derived from NSCLC and HNSCC cancers were tested for radiosensitization by MK-8776. The ability of MK-8776 to abrogate the radiation-induced G2 block was determined using flow cytometry. Effects on repair of radiation-induced DNA double strand breaks (DSBs) were determined on the basis of rad51, γ-H2AX and 53BP1 foci. Clonogenic survival analyses indicated that MK-8776 radiosensitized p53-defective tumor cells but not lines with wild-type p53. Abrogation of the G2 block was evident in both p53-defective cells and p53 wild-type lines indicating no correlation with radiosensitization. However, only p53-defective cells entered mitosis harboring unrepaired DSBs. MK-8776 appeared to inhibit repair of radiation-induced DSBs at early times after irradiation. A comparison of MK-8776 to the wee1 inhibitor, MK-1775, suggested both similarities and differences in their activities. In conclusion, MK-8776 radiosensitizes tumor cells by mechanisms that include abrogation of the G2 block and inhibition of DSB repair. Our findings support the clinical evaluation of MK-8776 in combination with radiation.
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225
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Yuan R, Vos HR, van Es RM, Chen J, Burgering BM, Westendorp B, de Bruin A. Chk1 and 14-3-3 proteins inhibit atypical E2Fs to prevent a permanent cell cycle arrest. EMBO J 2018; 37:embj.201797877. [PMID: 29363506 PMCID: PMC5830916 DOI: 10.15252/embj.201797877] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 12/29/2017] [Accepted: 01/04/2018] [Indexed: 12/22/2022] Open
Abstract
The atypical E2Fs, E2F7 and E2F8, act as potent transcriptional repressors of DNA replication genes providing them with the ability to induce a permanent S-phase arrest and suppress tumorigenesis. Surprisingly in human cancer, transcript levels of atypical E2Fs are frequently elevated in proliferating cancer cells, suggesting that the tumor suppressor functions of atypical E2Fs might be inhibited through unknown post-translational mechanisms. Here, we show that atypical E2Fs can be directly phosphorylated by checkpoint kinase 1 (Chk1) to prevent a permanent cell cycle arrest. We found that 14-3-3 protein isoforms interact with both E2Fs in a Chk1-dependent manner. Strikingly, Chk1 phosphorylation and 14-3-3-binding did not relocate or degrade atypical E2Fs, but instead, 14-3-3 is recruited to E2F7/8 target gene promoters to possibly interfere with transcription. We observed that high levels of 14-3-3 strongly correlate with upregulated transcription of atypical E2F target genes in human cancer. Thus, we reveal that Chk1 and 14-3-3 proteins cooperate to inactivate the transcriptional repressor functions of atypical E2Fs. This mechanism might be of particular importance to cancer cells, since they are exposed frequently to DNA-damaging therapeutic reagents.
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Affiliation(s)
- Ruixue Yuan
- Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Harmjan R Vos
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Robert M van Es
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Jing Chen
- Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Boudewijn Mt Burgering
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Bart Westendorp
- Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Alain de Bruin
- Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands .,Division Molecular Genetics, Department Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
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226
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H1/pHGFK1 nanoparticles exert anti-tumoural and radiosensitising effects by inhibition of MET in glioblastoma. Br J Cancer 2018; 118:522-533. [PMID: 29348487 PMCID: PMC5830599 DOI: 10.1038/bjc.2017.461] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Revised: 11/23/2017] [Accepted: 11/23/2017] [Indexed: 12/20/2022] Open
Abstract
Background: The therapeutic resistance to ionising radiation (IR) and anti-angiogenesis mainly impair the prognosis of patients with glioblastoma. The primary and secondary MET aberrant activation is one crucial factor for these resistances. The kringle 1 domain of hepatocyte growth factor (HGFK1), an angiogenic inhibitor, contains a high-affinity binding domain of MET; however, its effects on glioblastoma remain elusive. Methods: We formed the nanoparticles consisting of a folate receptor-targeted nanoparticle-mediated HGFK1 gene (H1/pHGFK1) and studied its anti-tumoural and radiosensitive activities in both subcutaneous and orthotopic human glioma cell-xenografted mouse models. We then elucidated its molecular mechanisms in human glioblastoma cell lines in vitro. Results: We demonstrated for the first time that peritumoural injection of H1/pHGFK1 nanoparticles significantly inhibited tumour growth and prolonged survival in tumour-bearing mice, as well as enhanced the anti-tumoural efficacies of IR in vivo by reducing Ki-67 expression, enhancing TUNEL staining-indicated apoptotic indexes, reducing microvascular intensity and reversing IR-induced MET overexpression in tumour tissues. Furthermore, we showed that HGFK1 suppressed the proliferation and induced cell apoptosis and enhanced sensitivity to IR in glioblastoma cell lines, mainly by suppressing the activities of MET receptor, down-regulating ATM-Chk2 axis but up-regulating Chk1. Conclusions: H1/pHGFK1 exerts anti-tumoural and radiosensitive activities mainly through the inhibition and reversal of IR-induced MET and ATM–Chk2 axis activities in glioblastoma. H1/pHGFK1 nanoparticles are a potential radiosensitiser and angiogenic inhibitor for glioblastoma treatment.
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227
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Bai X, Wang J, Huo L, Xie Y, Xie W, Xu G, Wang M. Serine/Threonine Kinase CHEK1-Dependent Transcriptional Regulation of RAD54L Promotes Proliferation and Radio Resistance in Glioblastoma. Transl Oncol 2017; 11:140-146. [PMID: 29287241 PMCID: PMC6002345 DOI: 10.1016/j.tranon.2017.11.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 11/28/2017] [Accepted: 11/28/2017] [Indexed: 12/11/2022] Open
Abstract
Accumulating evidence indicates that Checkpoint kinase 1 (CHEK1) plays an essential role in tumor cells and that it could induce cell proliferation and could be related to prognosis in multiple types of cancer. However, the biological role and molecular mechanism of CHEK1 in GBM still remain unclear. In this study, we identified that CHEK1 expression was enriched in glioblastoma (GBM) tumors and was functionally required for tumor proliferation and that its expression was associated to poor prognosis in GBM patients. Mechanically, CHEK1 induced radio resistance in GBM cells, and CHEK1 knockdown increased cell apoptosis when combined with radiotherapy via regulation of the DNA repair/recombination protein 54L (RAD54L) expression. Therapeutically, we found that CHEK1 inhibitor attenuated tumor growth both in vitro and in vivo. Collectively, CHEK1 promotes proliferation, induces radio resistance in GBM, and could become a potential therapeutic target for GBM.
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Affiliation(s)
- Xiaobin Bai
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaaxin, China, 710061
| | - Jia Wang
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaaxin, China, 710061
| | - Longwei Huo
- Department of Neurosurgery, The First Hospital of Yulin, Yulin, Shaanxi, China, 719000
| | - Yuchen Xie
- School of Medicine, Xi'an Jiaotong University, Xi'an, Shaaxin, China, 710061
| | - Wanfu Xie
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaaxin, China, 710061
| | - Gaofeng Xu
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaaxin, China, 710061
| | - Maode Wang
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaaxin, China, 710061.
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228
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Tao L, Cao Y, Wei Z, Jia Q, Yu S, Zhong J, Wang A, Woodgett JR, Lu Y. Xanthatin triggers Chk1-mediated DNA damage response and destabilizes Cdc25C via lysosomal degradation in lung cancer cells. Toxicol Appl Pharmacol 2017; 337:85-94. [PMID: 29074359 DOI: 10.1016/j.taap.2017.10.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 10/01/2017] [Accepted: 10/17/2017] [Indexed: 12/21/2022]
Abstract
Previous studies had shown that xanthatin, a natural xanthanolide sesquiterpene lactone, could induce mitotic arrest and apoptosis in non-small cell lung cancer (NSCLC) cells. Here, we examined whether the DNA damage response (DDR) could be a primary cytotoxic event underlying xanthatin-mediated anti-tumor activity. Using EdU incorporation assay in combination with novel imaging flow cytometry, our data indicated that xanthatin suppressed DNA replication, prevented cells from G2/M entry and increased the spot count of γH2AX nuclear foci. Given that checkpoint kinase 1 (Chk1) represents a core component in DDR-mediated cell cycle transition and the phosphorylation on Ser-345 is essential for kinase activation and function, we surprisingly found xanthatin distinctly modulated Ser-345 phosphorylation of Chk1 in A549 and H1299 cells. Further investigation on Cdc25C/CDK1/CyclinB1 signaling cascade in the absence or presence of pharmacological DDR inhibitors showed that xanthatin directly destabilized the protein levels of Cdc25C, and recovery of p53 expression in p53-deficient H1299 cells further intensified xanthatin-mediated inhibition of Cdc25C, suggesting p53-dependent regulation of Cdc25C in a DDR machinery. Moreover, exogenous expression of Cdc25C was also substantially repressed by xanthatin and partially impaired xanthatin-induced G2 arrest. In addition, xanthatin could induce accumulation of ubiquitinated Cdc25C without undergoing further proteasomal degradation. However, an alternative lysosomal proteolysis of Cdc25C was observed. Interestingly, lysosome-like vesicles were produced upon xanthatin treatment, accompanied by rapid accumulation of lysosomal associated membrane protein LAPM-1. Furthermore, vacuolar proton (V)-ATPases inhibitor bafilomycin A1 and lysosomal proteases inhibitor leupeptin could remarkably overturn the levels of Cdc25C in xanthatin-treated H1299 cells. Altogether, these data provide insight into how xanthatin can be effectively targeted DDR molecules towards certain tumors.
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Affiliation(s)
- Li Tao
- Department of Pharmacy, College of Medicine, Yangzhou University, Yangzhou, Jiangsu 225001, China
| | - Yuzhu Cao
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Zhonghong Wei
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Qi Jia
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Suyun Yu
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Jinqiu Zhong
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Ainyun Wang
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - James R Woodgett
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario M5G 1X5, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1X5, Canada.
| | - Yin Lu
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China.
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229
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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: 79] [Impact Index Per Article: 11.3] [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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230
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Schuler F, Weiss JG, Lindner SE, Lohmüller M, Herzog S, Spiegl SF, Menke P, Geley S, Labi V, Villunger A. Checkpoint kinase 1 is essential for normal B cell development and lymphomagenesis. Nat Commun 2017; 8:1697. [PMID: 29167438 PMCID: PMC5700047 DOI: 10.1038/s41467-017-01850-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 10/20/2017] [Indexed: 12/20/2022] Open
Abstract
Checkpoint kinase 1 (CHK1) is critical for intrinsic cell cycle control and coordination of cell cycle progression in response to DNA damage. Despite its essential function, CHK1 has been identified as a target to kill cancer cells and studies using Chk1 haploinsufficient mice initially suggested a role as tumor suppressor. Here, we report on the key role of CHK1 in normal B-cell development, lymphomagenesis and cell survival. Chemical CHK1 inhibition induces BCL2-regulated apoptosis in primary as well as malignant B-cells and CHK1 expression levels control the timing of lymphomagenesis in mice. Moreover, total ablation of Chk1 in B-cells arrests their development at the pro-B cell stage, a block that, surprisingly, cannot be overcome by inhibition of mitochondrial apoptosis, as cell cycle arrest is initiated as an alternative fate to limit the spread of damaged DNA. Our findings define CHK1 as essential in B-cell development and potent target to treat blood cancer.
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Affiliation(s)
- Fabian Schuler
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Johannes G Weiss
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Silke E Lindner
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Michael Lohmüller
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Sebastian Herzog
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Simon F Spiegl
- Division of Molecular Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Philipp Menke
- Division of Molecular Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Stephan Geley
- Division of Molecular Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Verena Labi
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria
| | - Andreas Villunger
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80, A-6020, Innsbruck, Austria. .,Tyrolean Cancer Research Institute, Innrain 66, A-6020, Innsbruck, Austria.
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231
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Majumder K, Etingov I, Pintel DJ. Protoparvovirus Interactions with the Cellular DNA Damage Response. Viruses 2017; 9:v9110323. [PMID: 29088070 PMCID: PMC5707530 DOI: 10.3390/v9110323] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 10/16/2017] [Accepted: 10/23/2017] [Indexed: 02/06/2023] Open
Abstract
Protoparvoviruses are simple single-stranded DNA viruses that infect many animal species. The protoparvovirus minute virus of mice (MVM) infects murine and transformed human cells provoking a sustained DNA damage response (DDR). This DDR is dependent on signaling by the ATM kinase and leads to a prolonged pre-mitotic cell cycle block that features the inactivation of ATR-kinase mediated signaling, proteasome-targeted degradation of p21, and inhibition of cyclin B1 expression. This review explores how protoparvoviruses, and specifically MVM, co-opt the common mechanisms regulating the DDR and cell cycle progression in order to prepare the host nuclear environment for productive infection.
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Affiliation(s)
- Kinjal Majumder
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Bond Life Sciences Center, Columbia, MO 65211, USA.
| | - Igor Etingov
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Bond Life Sciences Center, Columbia, MO 65211, USA.
| | - David J Pintel
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Bond Life Sciences Center, Columbia, MO 65211, USA.
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232
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Geneste CC, Massey AJ. Cell Density Affects the Detection of Chk1 Target Engagement by the Selective Inhibitor V158411. SLAS DISCOVERY 2017; 23:144-153. [PMID: 29048945 DOI: 10.1177/2472555217738534] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Understanding drug target engagement and the relationship to downstream pharmacology is critical for drug discovery. Here we have evaluated target engagement of Chk1 by the small-molecule inhibitor V158411 using two different target engagement methods (autophosphorylation and cellular thermal shift assay [CETSA]). Target engagement measured by these methods was subsequently related to Chk1 inhibitor-dependent pharmacology. Inhibition of autophosphorylation was a robust method for measuring V158411 Chk1 target engagement. In comparison, while target engagement determined using CETSA appeared robust, the V158411 CETSA target engagement EC50 values were 43- and 19-fold greater than the autophosphorylation IC50 values. This difference was attributed to the higher cell density in the CETSA assay configuration. pChk1 (S296) IC50 values determined using the CETSA assay conditions were 54- and 33-fold greater than those determined under standard conditions and were equivalent to the CETSA EC50 values. Cellular conditions, especially cell density, influenced the target engagement of V158411 for Chk1. The effects of high cell density on apparent compound target engagement potency should be evaluated when using target engagement assays that necessitate high cell densities (such as the CETSA conditions used in this study). In such cases, the subsequent relation of these data to downstream pharmacological changes should therefore be interpreted with care.
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233
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Reyes ED, Kulej K, Pancholi NJ, Akhtar LN, Avgousti DC, Kim ET, Bricker DK, Spruce LA, Koniski SA, Seeholzer SH, Isaacs SN, Garcia BA, Weitzman MD. Identifying Host Factors Associated with DNA Replicated During Virus Infection. Mol Cell Proteomics 2017; 16:2079-2097. [PMID: 28972080 DOI: 10.1074/mcp.m117.067116] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 07/14/2017] [Indexed: 01/22/2023] Open
Abstract
Viral DNA genomes replicating in cells encounter a myriad of host factors that facilitate or hinder viral replication. Viral proteins expressed early during infection modulate host factors interacting with viral genomes, recruiting proteins to promote viral replication, and limiting access to antiviral repressors. Although some host factors manipulated by viruses have been identified, we have limited knowledge of pathways exploited during infection and how these differ between viruses. To identify cellular processes manipulated during viral replication, we defined proteomes associated with viral genomes during infection with adenovirus, herpes simplex virus and vaccinia virus. We compared enrichment of host factors between virus proteomes and confirmed association with viral genomes and replication compartments. Using adenovirus as an illustrative example, we uncovered host factors deactivated by early viral proteins, and identified a subgroup of nucleolar proteins that aid virus replication. Our data sets provide valuable resources of virus-host interactions that affect proteins on viral genomes.
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Affiliation(s)
- Emigdio D Reyes
- From the ‡Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.,§Division of Protective Immunity and Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Katarzyna Kulej
- From the ‡Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.,§Division of Protective Immunity and Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Neha J Pancholi
- §Division of Protective Immunity and Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,¶Cell and Molecular Biology Graduate Group, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Lisa N Akhtar
- ‖Division of Infectious Diseases, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Daphne C Avgousti
- From the ‡Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.,§Division of Protective Immunity and Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Eui Tae Kim
- §Division of Protective Immunity and Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Daniel K Bricker
- From the ‡Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.,§Division of Protective Immunity and Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Lynn A Spruce
- **Protein and Proteomics Core, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Sarah A Koniski
- §Division of Protective Immunity and Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Steven H Seeholzer
- **Protein and Proteomics Core, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Stuart N Isaacs
- ‡‡Division of Infectious Diseases, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Benjamin A Garcia
- §§Epigenetics Program, Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Matthew D Weitzman
- From the ‡Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania; .,§Division of Protective Immunity and Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
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234
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Emptage RP, Schoenberger MJ, Ferguson KM, Marmorstein R. Intramolecular autoinhibition of checkpoint kinase 1 is mediated by conserved basic motifs of the C-terminal kinase-associated 1 domain. J Biol Chem 2017; 292:19024-19033. [PMID: 28972186 DOI: 10.1074/jbc.m117.811265] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 09/21/2017] [Indexed: 11/06/2022] Open
Abstract
Precise control of the cell cycle allows for timely repair of genetic material prior to replication. One factor intimately involved in this process is checkpoint kinase 1 (Chk1), a DNA damage repair inducing Ser/Thr protein kinase that contains an N-terminal kinase domain and a C-terminal regulatory region consisting of a ∼100-residue linker followed by a putative kinase-associated 1 (KA1) domain. We report the crystal structure of the human Chk1 KA1 domain, demonstrating striking structural homology with other sequentially diverse KA1 domains. Separately purified Chk1 kinase and KA1 domains are intimately associated in solution, which results in inhibition of Chk1 kinase activity. Using truncation mutants and site-directed mutagenesis, we define the inhibitory face of the KA1 domain as a series of basic residues residing on two conserved regions of the primary structure. These findings point to KA1-mediated intramolecular autoinhibition as a key regulatory mechanism of human Chk1, and provide new therapeutic possibilities with which to attack this validated oncology target with small molecules.
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Affiliation(s)
- Ryan P Emptage
- From the Department of Biochemistry and Biophysics and the Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104,
| | - Megan J Schoenberger
- the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, and
| | - Kathryn M Ferguson
- the Department of Pharmacology and Cancer Biology Institute, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Ronen Marmorstein
- From the Department of Biochemistry and Biophysics and the Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, .,the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, and
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235
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Tu Y, Liu H, Zhu X, Shen H, Ma X, Wang F, Huang M, Gong J, Li X, Wang Y, Guo C, Tang TS. Ataxin-3 promotes genome integrity by stabilizing Chk1. Nucleic Acids Res 2017; 45:4532-4549. [PMID: 28180282 PMCID: PMC5416811 DOI: 10.1093/nar/gkx095] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 02/07/2017] [Indexed: 12/27/2022] Open
Abstract
The Chk1 protein is essential for genome integrity maintenance and cell survival in eukaryotic cells. After prolonged replication stress, Chk1 can be targeted for proteasomal degradation to terminate checkpoint signaling after DNA repair finishes. To ensure proper activation of DNA damage checkpoint and DNA repair signaling, a steady-state level of Chk1 needs to be retained under physiological conditions. Here, we report a dynamic signaling pathway that tightly regulates Chk1 stability. Under unperturbed conditions and upon DNA damage, ataxin-3 (ATX3) interacts with Chk1 and protects it from DDB1/CUL4A- and FBXO6/CUL1-mediated polyubiquitination and subsequent degradation, thereby promoting DNA repair and checkpoint signaling. Under prolonged replication stress, ATX3 dissociates from Chk1, concomitant with a stronger binding between Chk1 and its E3 ligase, which causes Chk1 proteasomal degradation. ATX3 deficiency results in pronounced reduction of Chk1 abundance, compromised DNA damage response, G2/M checkpoint defect and decreased cell survival after replication stress, which can all be rescued by ectopic expression of ATX3. Taken together, these findings reveal ATX3 to be a novel deubiquitinase of Chk1, providing a new mechanism of Chk1 stabilization in genome integrity maintenance.
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Affiliation(s)
- Yingfeng Tu
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
- These authors contributed equally to the work as first authors
| | - Hongmei Liu
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
- These authors contributed equally to the work as first authors
| | - Xuefei Zhu
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
- These authors contributed equally to the work as first authors
| | - Hongyan Shen
- CAS Key Laboratory of Genomics and Precision Medicine, Beijing Institute of Genomics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaolu Ma
- CAS Key Laboratory of Genomics and Precision Medicine, Beijing Institute of Genomics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Fengli Wang
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Min Huang
- CAS Key Laboratory of Genomics and Precision Medicine, Beijing Institute of Genomics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Juanjuan Gong
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaoling Li
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Yun Wang
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Caixia Guo
- CAS Key Laboratory of Genomics and Precision Medicine, Beijing Institute of Genomics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
- To whom correspondence should be addressed. Tel: +86 10 64807296; Fax: +86 10 64807313; . Correspondence may also be addressed to Caixia Guo. Tel: +86 10 84097646; Fax: +86 10 84097720;
| | - Tie-Shan Tang
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
- To whom correspondence should be addressed. Tel: +86 10 64807296; Fax: +86 10 64807313; . Correspondence may also be addressed to Caixia Guo. Tel: +86 10 84097646; Fax: +86 10 84097720;
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236
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Herůdková J, Paruch K, Khirsariya P, Souček K, Krkoška M, Vondálová Blanářová O, Sova P, Kozubík A, Hyršlová Vaculová A. Chk1 Inhibitor SCH900776 Effectively Potentiates the Cytotoxic Effects of Platinum-Based Chemotherapeutic Drugs in Human Colon Cancer Cells. Neoplasia 2017; 19:830-841. [PMID: 28888100 PMCID: PMC5591453 DOI: 10.1016/j.neo.2017.08.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 08/04/2017] [Accepted: 08/04/2017] [Indexed: 01/11/2023] Open
Abstract
Although Chk1 kinase inhibitors are currently under clinical investigation as effective cancer cell sensitizers to the cytotoxic effects of numerous chemotherapeutics, there is still a considerable uncertainty regarding their role in modulation of anticancer potential of platinum-based drugs. Here we newly demonstrate the ability of one of the most specific Chk1 inhibitors, SCH900776 (MK-8776), to enhance human colon cancer cell sensitivity to the cytotoxic effects of platinum(II) cisplatin and platinum(IV)- LA-12 complexes. The combined treatment with SCH900776 and cisplatin or LA-12 results in apparent increase in G1/S phase-related apoptosis, stimulation of mitotic slippage, and senescence of HCT116 cells. We further show that the cancer cell response to the drug combinations is significantly affected by the p21, p53, and PTEN status. In contrast to their wt counterparts, the p53- or p21-deficient cells treated with SCH900776 and cisplatin or LA-12 enter mitosis and become polyploid, and the senescence phenotype is strongly suppressed. While the cell death induced by SCH900776 and cisplatin or LA-12 is significantly delayed in the absence of p53, the anticancer action of the drug combinations is significantly accelerated in p21-deficient cells, which is associated with stimulation of apoptosis beyond G2/M cell cycle phase. We also show that cooperative killing action of the drug combinations in HCT116 cells is facilitated in the absence of PTEN. Our results indicate that SCH900776 may act as an important modulator of cytotoxic response triggered by platinum-based drugs in colon cancer cells.
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Affiliation(s)
- Jarmila Herůdková
- Department of Cytokinetics, Institute of Biophysics, Czech Academy of Sciences, v.v.i., Brno, Czech Republic; Department of Animal Physiology and Immunology, Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Kamil Paruch
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University, Brno, Czech Republic; Center of Biomolecular and Cellular Engineering, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic
| | - Prashant Khirsariya
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University, Brno, Czech Republic; Center of Biomolecular and Cellular Engineering, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic
| | - Karel Souček
- Department of Cytokinetics, Institute of Biophysics, Czech Academy of Sciences, v.v.i., Brno, Czech Republic; Department of Animal Physiology and Immunology, Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic; Center of Biomolecular and Cellular Engineering, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic
| | - Martin Krkoška
- Department of Cytokinetics, Institute of Biophysics, Czech Academy of Sciences, v.v.i., Brno, Czech Republic; Department of Animal Physiology and Immunology, Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Olga Vondálová Blanářová
- Department of Cytokinetics, Institute of Biophysics, Czech Academy of Sciences, v.v.i., Brno, Czech Republic
| | - Petr Sova
- Platinum Pharmaceuticals, a.s., Brno, Czech Republic
| | - Alois Kozubík
- Department of Cytokinetics, Institute of Biophysics, Czech Academy of Sciences, v.v.i., Brno, Czech Republic; Department of Animal Physiology and Immunology, Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Alena Hyršlová Vaculová
- Department of Cytokinetics, Institute of Biophysics, Czech Academy of Sciences, v.v.i., Brno, Czech Republic.
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237
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Ogden A, Rida PCG, Aneja R. Centrosome amplification: a suspect in breast cancer and racial disparities. Endocr Relat Cancer 2017; 24:T47-T64. [PMID: 28515047 PMCID: PMC5837860 DOI: 10.1530/erc-17-0072] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 05/17/2017] [Indexed: 12/31/2022]
Abstract
The multifaceted involvement of centrosome amplification (CA) in tumorigenesis is coming into focus following years of meticulous experimentation, which have elucidated the powerful abilities of CA to promote cellular invasion, disrupt stem cell division, drive chromosomal instability (CIN) and perturb tissue architecture, activities that can accelerate tumor progression. Integration of the extant in vitro, in vivo and clinical data suggests that in some tissues CA may be a tumor-initiating event, in others a consequential 'hit' in multistep tumorigenesis, and in some others, non-tumorigenic. However, in vivo data are limited and primarily focus on PLK4 (which has CA-independent mechanisms by which it promotes aggressive cellular phenotypes). In vitro breast cancer models suggest that CA can promote tumorigenesis in breast cancer cells in the setting of p53 loss or mutation, which can both trigger CA and promote cellular tolerance to its tendency to slow proliferation and induce aneuploidy. It is thus our perspective that CA is likely an early hit in multistep breast tumorigenesis that may sometimes be lost to preserve aggressive karyotypes acquired through centrosome clustering-mediated CIN, both numerical and structural. We also envision that the robust link between p53 and CA may underlie, to a considerable degree, racial health disparity in breast cancer outcomes. This question is clinically significant because, if it is true, then analysis of centrosomal profiles and administration of centrosome declustering drugs could prove highly efficacious in risk stratifying breast cancers and treating African American (AA) women with breast cancer.
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Affiliation(s)
- Angela Ogden
- Department of BiologyGeorgia State University, Atlanta, Georgia, USA
| | | | - Ritu Aneja
- Department of BiologyGeorgia State University, Atlanta, Georgia, USA
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238
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Mohanraj V, Ponnuswamy S. Design, synthesis, characterisation, conformation and biological investigation of N-acyl r-2,c-6-bis (4-methoxyphenyl)-c-3,t-3-dimethylpiperidin-4-ones. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2017.05.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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239
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Jin H, Xu G, Zhang Q, Pang Q, Fang M. Synaptotagmin-7 is overexpressed in hepatocellular carcinoma and regulates hepatocellular carcinoma cell proliferation via Chk1-p53 signaling. Onco Targets Ther 2017; 10:4283-4293. [PMID: 28919777 PMCID: PMC5587153 DOI: 10.2147/ott.s143619] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Background Synaptotagmin-7 (Syt-7) is a member of the synaptotagmin (Syt) family, which plays an important role in many physiological and pathological processes. However, to the best of our knowledge, there is no study describing its function in tumors, particularly in hepatocellular carcinoma (HCC). Therefore, in this study, we examined the role of Syt-7 in HCC and attempted to elucidate its underlying mechanism. Materials and methods We examined the expression levels of Syt-7 in HCC cell lines and normal hepatocytes by real-time quantitative polymerase chain reaction analysis. The effects of Syt-7 knockdown on in vitro cell growth were assessed by Celigo image cytometry, MTT assay, colony formation assay, and cell cycle analysis. In vivo tumorigenesis was evaluated using a nude mouse model. The underlying molecular mechanism was evaluated using a PathScan Stress Signaling Antibody Array. Results Syt-7 mRNA levels were highly expressed in Huh-7 and Hep3B cells; moderately expressed in SMMC-7721, HepG2, and BEL-7402 cells; and lowly expressed in normal hepatocytes L-O2. Functional experiments demonstrated that Syt-7 knockdown significantly suppressed cell proliferation and induced cell cycle arrest by increasing phosphorylation of Chk1 and p53. Furthermore, Syt-7 knockdown remarkably reduced the growth of xenograft tumors in mice. Conclusion The results of this study suggest that Syt-7 plays a vital role in tumorigenesis and in the development of HCC. Syt-7 can be used as a new diagnostic and therapeutic target in HCC.
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Affiliation(s)
- Hao Jin
- School of Medicine, Shandong University, Jinan.,Department of Hepatic Surgery, Anhui Provincial Hospital, Hefei.,Department of Hepatobiliary Surgery, The First Affiliated Hospital, Bengbu Medical College, Bengbu, Anhui, People's Republic of China
| | - Geliang Xu
- Department of Hepatic Surgery, Anhui Provincial Hospital, Hefei
| | - Qiang Zhang
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Bengbu Medical College, Bengbu, Anhui, People's Republic of China
| | - Qing Pang
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Bengbu Medical College, Bengbu, Anhui, People's Republic of China
| | - Meifang Fang
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Bengbu Medical College, Bengbu, Anhui, People's Republic of China
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240
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Zhao F, Gao Y, Chu X, Chen J, Huang L, Zhao J, Zhang J, Zhao S. ROS attenuates the antitumor effect of Raddeanin on ovarian cancer cells Skov3. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2017; 10:8292-8302. [PMID: 31966680 PMCID: PMC6965409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 06/20/2017] [Indexed: 06/10/2023]
Abstract
Epithelial ovarian cancer is the fourth commonest cause of female cancer death, but no proper evidence had proved that surgery could prolong the survival time. Hence, new effective chemotherapy is necessary to improve the survival. Raddeanin A (RA), anoleanane-type triterpenoid sponin, is isolated from Anemone raddeana. Previous study had proved that RA exerted antitumor activity through inhibiting proliferation and promoting apoptosis of some kinds of cancer cell. ROS is a double-edged sword for tumors and might contribute to therapy resistant. In this study, we discuss at the first time whether ROS was involved in the antitumor effect of RA on Skov3 cells, and analysis the mechanism. The results showed that after be treated by RA, the proliferation of Skov3 was inhibited, and this effect can be enhanced by ROS inhibitor NAC. Pretreated with NAC can enhance the cell cycle block but not apoptosis induced by RA. Moreover, as a by-production of RA, ROS induced autophagy can attenuate RA's antitumor activity, and autophagy inhibitor 3-MA could recover RA's antitumor effect. These results demonstrated that ROS and autophagy could be considered as two pro-tumor factors in some conditions. The combination of RA and ROS inhibitor or autophagy inhibitor or both of them may be the novel strategies at least in ovarian cancer therapy.
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Affiliation(s)
- Fan Zhao
- China Japan Union Hospital, Jilin UniversityChangchun 130041, China
| | - Yuxia Gao
- School of Nursing, Jilin UniversityChangchun 130021, China
| | - Xiuming Chu
- The Second Hospital, Jilin UniversityChangchun 130041, China
- The Fourth Hospital, Jilin UniversityChangchun 130041, China
| | - Junyu Chen
- The Second Hospital, Jilin UniversityChangchun 130041, China
| | - Liandi Huang
- The Second Hospital, Jilin UniversityChangchun 130041, China
| | - Jing Zhao
- Medical Department, Yanbian UniversityYanji 133000, China
| | - Jiayue Zhang
- Medical Department, Yanbian UniversityYanji 133000, China
| | - Shuhua Zhao
- The Second Hospital, Jilin UniversityChangchun 130041, China
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241
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Ning J, Wakimoto H, Peters C, Martuza RL, Rabkin SD. Rad51 Degradation: Role in Oncolytic Virus-Poly(ADP-Ribose) Polymerase Inhibitor Combination Therapy in Glioblastoma. J Natl Cancer Inst 2017; 109:1-13. [PMID: 28376211 DOI: 10.1093/jnci/djw229] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 09/02/2016] [Indexed: 02/06/2023] Open
Abstract
Background Clinical success of poly(ADP-ribose) polymerase inhibitors (PARP i ) has been limited to repair-deficient cancers and by resistance. Oncolytic herpes simplex viruses (oHSVs) selectively kill cancer cells, irrespective of mutation, and manipulate DNA damage responses (DDR). Here, we explore potential synthetic lethal-like interactions between oHSV and PARP i . Methods The efficacy of combining PARP i , oHSV MG18L, and G47Δ in killing patient-derived glioblastoma stem cells (GSCs) was assessed using cell viability assays and Chou-Talalay synergy analysis. Effects on DDR pathways, apoptosis, and cell cycle after manipulation with pharmacological inhibitors and lentivirus-mediated knockdown or overexpression were examined by immunoblotting and FACS. In vivo efficacy was evaluated in two GSC-derived orthotopic xenograft models (n = 7-8 per group). All statistical tests were two-sided. Results GSCs are differentially sensitive to PARP i despite uniform inhibition of PARP activity. oHSV sensitized GSCs to PARP i , irrespective of their PARP i sensitivity through selective proteasomal degradation of key DDR proteins; Rad51, mediating the combination effects; and Chk1. Rad51 degradation required HSV DNA replication. This synthetic lethal-like interaction increased DNA damage, apoptosis, and cell death in vitro and in vivo. Combined treatment of mice bearing PARP i -sensitive or -resistant GSC-derived brain tumors greatly extended median survival compared to either agent alone (vs olaparib: P ≤.001; vs MG18L: P = .005; median survival for sensitive of 83 [95% CI = 77 to 86], 94 [95% CI = 75 to 107], 102 [95% CI = 85 to 110], and 131 [95% CI = 108 to 170] days and for resistant of 54 [95% CI = 52 to 58], 56 [95% CI = 52 to 61], 62 [95% CI = 56 to 72], and 75 [95% CI = 64 to 90] days for mock, PARPi, oHSV, and combination, respectively). Conclusions The unique oHSV property to target multiple components of DDR generates cancer selective sensitivity to PARP i . This combination of oHSV with PARP i is a new anticancer strategy that overcomes the clinical barriers of PARP i resistance and DNA repair proficiency and is applicable not only to glioblastoma, an invariably lethal tumor, but also to other tumor types.
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Affiliation(s)
- Jianfang Ning
- Molecular Neurosurgery Laboratory, Brain Tumor Research Center, Massachusetts General Hospital, Boston, MA, USA.,Department of Neurosurgery, Harvard Medical School, Boston, MA, USA
| | - Hiroaki Wakimoto
- Molecular Neurosurgery Laboratory, Brain Tumor Research Center, Massachusetts General Hospital, Boston, MA, USA.,Department of Neurosurgery, Harvard Medical School, Boston, MA, USA
| | - Cole Peters
- Molecular Neurosurgery Laboratory, Brain Tumor Research Center, Massachusetts General Hospital, Boston, MA, USA.,Program in Virology, Harvard Medical School, Boston, MA, USA
| | - Robert L Martuza
- Molecular Neurosurgery Laboratory, Brain Tumor Research Center, Massachusetts General Hospital, Boston, MA, USA.,Department of Neurosurgery, Harvard Medical School, Boston, MA, USA
| | - Samuel D Rabkin
- Molecular Neurosurgery Laboratory, Brain Tumor Research Center, Massachusetts General Hospital, Boston, MA, USA.,Department of Neurosurgery, Harvard Medical School, Boston, MA, USA.,Program in Virology, Harvard Medical School, Boston, MA, USA
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242
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Deneke VE, Melbinger A, Vergassola M, Di Talia S. Waves of Cdk1 Activity in S Phase Synchronize the Cell Cycle in Drosophila Embryos. Dev Cell 2017; 38:399-412. [PMID: 27554859 DOI: 10.1016/j.devcel.2016.07.023] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 06/13/2016] [Accepted: 07/26/2016] [Indexed: 01/16/2023]
Abstract
Embryos of most metazoans undergo rapid and synchronous cell cycles following fertilization. While diffusion is too slow for synchronization of mitosis across large spatial scales, waves of Cdk1 activity represent a possible process of synchronization. However, the mechanisms regulating Cdk1 waves during embryonic development remain poorly understood. Using biosensors of Cdk1 and Chk1 activities, we dissect the regulation of Cdk1 waves in the Drosophila syncytial blastoderm. We show that Cdk1 waves are not controlled by the mitotic switch but by a double-negative feedback between Cdk1 and Chk1. Using mathematical modeling and surgical ligations, we demonstrate a fundamental distinction between S phase Cdk1 waves, which propagate as active trigger waves in an excitable medium, and mitotic Cdk1 waves, which propagate as passive phase waves. Our findings show that in Drosophila embryos, Cdk1 positive feedback serves primarily to ensure the rapid onset of mitosis, while wave propagation is regulated by S phase events.
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Affiliation(s)
- Victoria E Deneke
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Anna Melbinger
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Massimo Vergassola
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Stefano Di Talia
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.
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243
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Molecular signaling cascades involved in nonmelanoma skin carcinogenesis. Biochem J 2017; 473:2973-94. [PMID: 27679857 DOI: 10.1042/bcj20160471] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 06/10/2016] [Indexed: 12/17/2022]
Abstract
Nonmelanoma skin cancer (NMSC) is the most common cancer worldwide and the incidence continues to rise, in part due to increasing numbers in high-risk groups such as organ transplant recipients and those taking photosensitizing medications. The most significant risk factor for NMSC is ultraviolet radiation (UVR) from sunlight, specifically UVB, which is the leading cause of DNA damage, photoaging, and malignant transformation in the skin. Activation of apoptosis following UVR exposure allows the elimination of irreversibly damaged cells that may harbor oncogenic mutations. However, UVR also activates signaling cascades that promote the survival of these potentially cancerous cells, resulting in tumor initiation. Thus, the UVR-induced stress response in the skin is multifaceted and requires coordinated activation of numerous pathways controlling DNA damage repair, inflammation, and kinase-mediated signal transduction that lead to either cell survival or cell death. This review focuses on the central signaling mechanisms that respond to UVR and the subsequent cellular changes. Given the prevalence of NMSC and the resulting health care burden, many of these pathways provide promising targets for continued study aimed at both chemoprevention and chemotherapy.
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244
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Oliveira ML, Akkapeddi P, Alcobia I, Almeida AR, Cardoso BA, Fragoso R, Serafim TL, Barata JT. From the outside, from within: Biological and therapeutic relevance of signal transduction in T-cell acute lymphoblastic leukemia. Cell Signal 2017. [PMID: 28645565 DOI: 10.1016/j.cellsig.2017.06.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological cancer that arises from clonal expansion of transformed T-cell precursors. In this review we summarize the current knowledge on the external stimuli and cell-intrinsic lesions that drive aberrant activation of pivotal, pro-tumoral intracellular signaling pathways in T-cell precursors, driving transformation, leukemia expansion, spread or resistance to therapy. In addition to their pathophysiological relevance, receptors and kinases involved in signal transduction are often attractive candidates for targeted drug development. As such, we discuss also the potential of T-ALL signaling players as targets for therapeutic intervention.
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Affiliation(s)
- Mariana L Oliveira
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Padma Akkapeddi
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Isabel Alcobia
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Histologia e Biologia do Desenvolvimento, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Afonso R Almeida
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Bruno A Cardoso
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Rita Fragoso
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Teresa L Serafim
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - João T Barata
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal.
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245
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A novel function of hepatocyte growth factor in the activation of checkpoint kinase 1 phosphorylation in colon cancer cells. Mol Cell Biochem 2017; 436:29-38. [PMID: 28573382 PMCID: PMC5674134 DOI: 10.1007/s11010-017-3075-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 05/25/2017] [Indexed: 01/02/2023]
Abstract
The ATR/checkpoint kinase 1 (Chk1) pathway plays an essential role in modulating the DNA damage response and homologous recombination. Particularly, Chk1 phosphorylation is related to cancer prognosis and therapeutic resistance. Some receptor tyrosine kinases participate in the regulation of Chk1 phosphorylation; however, the effect of hepatocyte growth factor (HGF) on Chk1 phosphorylation is unknown. In the present study, we demonstrated that HGF moderately activated Chk1 phosphorylation in colon cancer cells by upregulating TopBP1 and RAD51, and promoting TopBP1–ATR complex formation. Furthermore, AKT activity, which was promoted by HGF, served as an important mediator linking HGF/MET signaling and Chk1 phosphorylation. Depleting AKT activity attenuated basal expression of p-Chk1 and HGF-induced Chk1 activation. Moreover, AKT activity directly regulated TopBP1 and RAD51 expression. AKT inhibition suppressed HGF-induced upregulation of TopBP1 and RAD51, and enhanced TopBP1/ATR complex formation. Our results show that HGF was involved in regulating Chk1 phosphorylation, and further demonstrate that AKT activity was responsible for this HGF-induced Chk1 phosphorylation. These findings might potentially result in management of prognosis and therapeutic sensitivity in cancer therapy.
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246
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Jadali A, Ying YLM, Kwan KY. Activation of CHK1 in Supporting Cells Indirectly Promotes Hair Cell Survival. Front Cell Neurosci 2017; 11:137. [PMID: 28572758 PMCID: PMC5435747 DOI: 10.3389/fncel.2017.00137] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 04/21/2017] [Indexed: 12/15/2022] Open
Abstract
The sensory hair cells of the inner ear are exquisitely sensitive to ototoxic insults. Loss of hair cells after exposure to ototoxic agents causes hearing loss. Chemotherapeutic agents such as cisplatin causes hair cell loss. Cisplatin forms DNA mono-adducts as well as intra- and inter-strand DNA crosslinks. DNA cisplatin adducts are repaired through the DNA damage response. The decision between cell survival and cell death following DNA damage rests on factors that are involved in determining damage tolerance, cell survival and apoptosis. Cisplatin damage on hair cells has been the main focus of many ototoxic studies, yet the effect of cisplatin on supporting cells has been largely ignored. In this study, the effects of DNA damage response in cochlear supporting cells were interrogated. Supporting cells play a major role in the development, maintenance and oto-protection of hair cells. Loss of supporting cells may indirectly affect hair cell survival or maintenance. Activation of the Phosphoinositide 3-Kinase (PI3K) signaling was previously shown to promote hair cell survival. To test whether activating PI3K signaling promotes supporting cell survival after cisplatin damage, cochlear explants from the neural subset (NS) Cre Pten conditional knockout mice were employed. Deletion of Phosphatase and Tensin Homolog (PTEN) activates PI3K signaling in multiple cell types within the cochlea. Supporting cells lacking PTEN showed increased cell survival after cisplatin damage. Supporting cells lacking PTEN also showed increased phosphorylation of Checkpoint Kinase 1 (CHK1) levels after cisplatin damage. Nearest neighbor analysis showed increased numbers of supporting cells with activated PI3K signaling in close proximity to surviving hair cells in cisplatin damaged cochleae. We propose that increased PI3K signaling promotes supporting cell survival through phosphorylation of CHK1 and increased survival of supporting cells indirectly increases hair cell survival after cisplatin damage.
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Affiliation(s)
- Azadeh Jadali
- Department of Cell Biology and Neuroscience, Rutgers UniversityPiscataway, NJ, USA.,Stem Cell Research Center and Keck Center for Collaborative Neuroscience, Rutgers UniversityPiscataway, NJ, USA.,3D BiotekBridgewater, NJ, USA
| | - Yu-Lan M Ying
- Department of Otolaryngology-Head and Neck Surgery, Rutgers New Jersey Medical SchoolNewark, NJ, USA
| | - Kelvin Y Kwan
- Department of Cell Biology and Neuroscience, Rutgers UniversityPiscataway, NJ, USA.,Stem Cell Research Center and Keck Center for Collaborative Neuroscience, Rutgers UniversityPiscataway, NJ, USA
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247
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Sen T, Tong P, Stewart CA, Cristea S, Valliani A, Shames DS, Redwood AB, Fan YH, Li L, Glisson BS, Minna JD, Sage J, Gibbons DL, Piwnica-Worms H, Heymach JV, Wang J, Byers LA. CHK1 Inhibition in Small-Cell Lung Cancer Produces Single-Agent Activity in Biomarker-Defined Disease Subsets and Combination Activity with Cisplatin or Olaparib. Cancer Res 2017; 77:3870-3884. [PMID: 28490518 DOI: 10.1158/0008-5472.can-16-3409] [Citation(s) in RCA: 138] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/15/2017] [Accepted: 05/03/2017] [Indexed: 12/18/2022]
Abstract
Effective targeted therapies for small-cell lung cancer (SCLC), the most aggressive form of lung cancer, remain urgently needed. Here we report evidence of preclinical efficacy evoked by targeting the overexpressed cell-cycle checkpoint kinase CHK1 in SCLC. Our studies employed RNAi-mediated attenuation or pharmacologic blockade with the novel second-generation CHK1 inhibitor prexasertib (LY2606368), currently in clinical trials. In SCLC models in vitro and in vivo, LY2606368 exhibited strong single-agent efficacy, augmented the effects of cisplatin or the PARP inhibitor olaparib, and improved the response of platinum-resistant models. Proteomic analysis identified CHK1 and MYC as top predictive biomarkers of LY2606368 sensitivity, suggesting that CHK1 inhibition may be especially effective in SCLC with MYC amplification or MYC protein overexpression. Our findings provide a preclinical proof of concept supporting the initiation of a clinical efficacy trial in patients with platinum-sensitive or platinum-resistant relapsed SCLC. Cancer Res; 77(14); 3870-84. ©2017 AACR.
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Affiliation(s)
- Triparna Sen
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Pan Tong
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - C Allison Stewart
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Sandra Cristea
- Department of Pediatrics, Stanford University, Stanford, California
- Department of Genetics, Stanford University, Stanford, California
| | - Aly Valliani
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - David S Shames
- Department of Oncology Biomarker Development, Genentech Inc., South San Francisco, California
| | - Abena B Redwood
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - You Hong Fan
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Lerong Li
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Bonnie S Glisson
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - John D Minna
- Hamon Center for Therapeutic Oncology Research, The University of Texas Southwestern, Dallas, Texas
| | - Julien Sage
- Department of Pediatrics, Stanford University, Stanford, California
- Department of Genetics, Stanford University, Stanford, California
| | - Don L Gibbons
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Helen Piwnica-Worms
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - John V Heymach
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jing Wang
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Lauren Averett Byers
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
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248
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Regulation of CHK1 by mTOR contributes to the evasion of DNA damage barrier of cancer cells. Sci Rep 2017; 7:1535. [PMID: 28484242 PMCID: PMC5431544 DOI: 10.1038/s41598-017-01729-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 04/03/2017] [Indexed: 02/05/2023] Open
Abstract
Oncogenic transformation leads to dysregulated cell proliferation, nutrient deficiency, and hypoxia resulting in metabolic stress and increased DNA damage. In normal cells, such metabolic stress leads to inhibition of signaling through the mammalian Target of Rapamycin Complex 1 (mTORC1), reduction of protein translation, cell cycle arrest, and conservation of energy. In contrast, negative regulation of mTORC1 signaling by DNA damage is abrogated in many cancer cells, thus mTORC1 signaling remains active under microenvironmental conditions that potentially promote endogenous DNA damage. Here we report that mTORC1 signaling suppresses endogenous DNA damage and replication stress. Pharmacological inhibition of mTOR signaling resulted in phosphorylation of H2AX concomitant with the decrease of CHK1 levels both in cell culture and mouse rhadomyosarcoma xenografts. Further results demonstrated that mTORC1-S6K1 signaling controls transcription of CHK1 via Rb-E2F by upregulating cyclin D and E. Consistent with these results, downregulation of CHK1 by inhibition of mTOR kinase resulted in defects in the slow S phase progression following DNA damage. These results indicate that, under stressful conditions, maintained mTORC1 signaling in cancer cells promotes survival by suppressing endogenous DNA damage, and may control cell fate through the regulation of CHK1.
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249
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He Y, Liu J, Zhao Z, Zhao H. Bioinformatics analysis of gene expression profiles of esophageal squamous cell carcinoma. Dis Esophagus 2017; 30:1-8. [PMID: 28375447 DOI: 10.1093/dote/dow018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Indexed: 12/11/2022]
Abstract
The objective of this study is to explore the potential target genes in the pathogenesis of esophageal squamous cell carcinoma (ESCC). The mRNA expression profile data of GSE17351 were downloaded from the Gene Expression Omnibus database, including five paired ESCC and normal tissue samples from five ESCC patients. The differentially expressed genes (DEGs) between ESCC and normal samples were identified using the limma package. The identified DEGs were then performed clustering analysis and functional enrichment analysis. Additionally, gene-miRNA network, gene-transcription factor network, and protein-protein interaction (PPI) network for the DEGs were constructed, and then significant modules were selected from the constructed PPI network. Furthermore, esophageal carcinoma RNAseq data including 185 esophageal carcinoma and 13 normal samples were downloaded from The Cancer Genome Atlas database to confirm our results. A total of 409 up- and 341 downregulated DEGs were identified. The DEGs were separated into two clusters and were mainly enriched in cell cycle function. CHEK1, CCNA2, COL11A1, and MME were hub nodes in the PPI network. Besides, total seven modules were selected in the PPI network. Genes in the most significant module were upregulated and were enriched in cell cycle. The Cancer Genome Atlas data validation identified 370 DEGs, all of which were differentially expressed in the GSE17351 dataset. Besides, the expression change direction was consistent with the DEGs in GSE17351. Cell cycle may play a role in ESCC development. The genes such as CHEK1, CCNA2, COL11A1, and MME may be served as target genes in ESCC treatment.
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250
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The Intra-S Checkpoint Responses to DNA Damage. Genes (Basel) 2017; 8:genes8020074. [PMID: 28218681 PMCID: PMC5333063 DOI: 10.3390/genes8020074] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Revised: 02/08/2017] [Accepted: 02/08/2017] [Indexed: 02/03/2023] Open
Abstract
Faithful duplication of the genome is a challenge because DNA is susceptible to damage by a number of intrinsic and extrinsic genotoxins, such as free radicals and UV light. Cells activate the intra-S checkpoint in response to damage during S phase to protect genomic integrity and ensure replication fidelity. The checkpoint prevents genomic instability mainly by regulating origin firing, fork progression, and transcription of G1/S genes in response to DNA damage. Several studies hint that regulation of forks is perhaps the most critical function of the intra-S checkpoint. However, the exact role of the checkpoint at replication forks has remained elusive and controversial. Is the checkpoint required for fork stability, or fork restart, or to prevent fork reversal or fork collapse, or activate repair at replication forks? What are the factors that the checkpoint targets at stalled replication forks? In this review, we will discuss the various pathways activated by the intra-S checkpoint in response to damage to prevent genomic instability.
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