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Ueno H, Hoshino T, Yano W, Tsukioka S, Suzuki T, Hara S, Ogino Y, Chong KT, Suzuki T, Tsuji S, Itadani H, Yamamiya I, Otsu Y, Ito S, Yonekura T, Terasaka M, Tanaka N, Miyahara S. TAS1553, a small molecule subunit interaction inhibitor of ribonucleotide reductase, exhibits antitumor activity by causing DNA replication stress. Commun Biol 2022; 5:571. [PMID: 35681099 PMCID: PMC9184620 DOI: 10.1038/s42003-022-03516-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 05/22/2022] [Indexed: 01/03/2023] Open
Abstract
Ribonucleotide reductase (RNR) is composed of two non-identical subunits, R1 and R2, and plays a crucial role in balancing the cellular dNTP pool, establishing it as an attractive cancer target. Herein, we report the discovery of a highly potent and selective small-molecule inhibitor, TAS1553, targeting protein-protein interaction between R1 and R2. TAS1553 is also expected to demonstrate superior selectivity because it does not directly target free radical or a substrate binding site. TAS1553 has shown antiproliferative activity in human cancer cell lines, dramatically reducing the intracellular dATP pool and causing DNA replication stress. Furthermore, we identified SLFN11 as a biomarker that predicts the cytotoxic effect of TAS1553. Oral administration of TAS1553 demonstrated robust antitumor efficacy against both hematological and solid cancer xenograft tumors and also provided a significant survival benefit in an acute myelogenous leukemia model. Our findings strongly support the evaluation of TAS1553 in clinical trials. A small-molecule protein-protein interaction inhibitor of ribonucleotide reductase subunit, TAS1553, is shown to inhibit growth of both hematological and solid cancer xenograft tumors following oral administration in mice.
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Menendez D, Anand JR, Murphy CC, Bell WJ, Fu J, Slepushkina N, Buehler E, Martin SE, Lal-Nag M, Nitiss JL, Resnick MA. Etoposide-induced DNA damage is increased in p53 mutants: identification of ATR and other genes that influence effects of p53 mutations on Top2-induced cytotoxicity. Oncotarget 2022; 13:332-346. [PMID: 35178190 PMCID: PMC8845119 DOI: 10.18632/oncotarget.28195] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 01/28/2022] [Indexed: 11/25/2022] Open
Abstract
The functional status of the tumor suppressor p53 is a critical component in determining the sensitivity of cancer cells to many chemotherapeutic agents. DNA topoisomerase II (Top2) plays essential roles in DNA metabolism and is the target of FDA approved chemotherapeutic agents. Topoisomerase targeting drugs convert the enzyme into a DNA damaging agent and p53 influences cellular responses to these agents. We assessed the impact of the loss of p53 function on the formation of DNA damage induced by the Top2 poison etoposide. Using human HCT116 cells, we found resistance to etoposide in cell growth assays upon the functional loss of p53. Nonetheless, cells lacking fully functional p53 were etoposide hypersensitive in clonogenic survival assays. This complex role of p53 led us to directly examine the effects of p53 status on topoisomerase-induced DNA damage. A deficiency in functional p53 resulted in elevated levels of the Top2 covalent complexes (Top2cc) in multiple cell lines. Employing genome-wide siRNA screens, we identified a set of genes for which reduced expression resulted in enhanced synthetic lethality upon etoposide treatment of p53 defective cells. We focused on one hit from this screen, ATR, and showed that decreased expression sensitized the p53-defective cells to etoposide in all assays and generated elevated levels of Top2cc in both p53 proficient and deficient cells. Our findings suggest that a combination of etoposide treatment with functional inactivation of DNA repair in p53 defective cells could be used to enhance the therapeutic efficacy of Top2 targeting agents.
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Affiliation(s)
- Daniel Menendez
- Chromosomal Stability Group, Genome Integrity and Structural Biology Laboratory, NIEHS, NIH, Durham, NC 27709, USA
- Environmental Cardiopulmonary Disease Group, Immunity, Inflammation and Disease Laboratory, NIEHS, NIH, Durham, NC 27709, USA
- These authors contributed equally to this work
| | - Jay R. Anand
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois, Rockford, IL 61107, USA
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- These authors contributed equally to this work
| | - Carri C. Murphy
- Chromosomal Stability Group, Genome Integrity and Structural Biology Laboratory, NIEHS, NIH, Durham, NC 27709, USA
| | - Whitney J. Bell
- Chromosomal Stability Group, Genome Integrity and Structural Biology Laboratory, NIEHS, NIH, Durham, NC 27709, USA
| | - Jiaqi Fu
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, NIH, Bethesda, MD 20850, USA
| | - Nadia Slepushkina
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, NIH, Bethesda, MD 20850, USA
| | - Eugen Buehler
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, NIH, Bethesda, MD 20850, USA
| | - Scott E. Martin
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, NIH, Bethesda, MD 20850, USA
| | - Madhu Lal-Nag
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, NIH, Bethesda, MD 20850, USA
| | - John L. Nitiss
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois, Rockford, IL 61107, USA
| | - Michael A. Resnick
- Chromosomal Stability Group, Genome Integrity and Structural Biology Laboratory, NIEHS, NIH, Durham, NC 27709, USA
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Yang M, Yao P, Lang X, Li X, Zhang D. Ribonucleotide reductase subunit M2 promotes proliferation and epithelial-mesenchymal transition via the JAK2/STAT3 signaling pathway in retinoblastoma. Bioengineered 2021; 12:12800-12811. [PMID: 34895038 PMCID: PMC8809947 DOI: 10.1080/21655979.2021.2001241] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 11/05/2022] Open
Abstract
Retinoblastoma (RB) is an intraocular malignant tumor that often occurs in children. Along with the improvement of treatment strategies, the cure rate of RB has increased significantly. However, the treatment of advanced and recurrent RB remains as a critical challenge. Therefore, studying the molecular mechanisms underlying the progression of RB is essential for the development of novel and effective therapeutic strategies. Through the analysis of a previously published microarray study, we found that ribonucleotide reductase subunit M2 (RRM2) was highly expressed in RB tissues as compared to normal tissues. The purpose of this study is to clarify the role and mechanism of RRM2 in regulating the progression of RB. We first demonstrated that RRM2 expression level in RB tissues and cell lines was significantly higher when compared to that in normal retinal tissue and cell lines, and high RRM2 expression level was associated with a poorer overall survival of patients. In RB cells, RRM2 overexpression promoted cell proliferation, migration, invasion and epithelial-mesenchymal transformation (EMT), while RRM2 silencing suppressed these biological features. Silencing RRM2 reduced the activation of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway, and the presence of JAK2/STAT3 signaling pathway inhibitor INCB attenuated the effect of RRM2 overexpression. Collectively, our data indicate that RRM2 promotes the progression of RB by activating JAK2/STAT3 signaling pathway. Targeting RRM2/JAK2/STAT3 axis lays a theoretical foundation for the formulation of novel RB therapy.
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Affiliation(s)
- Min Yang
- Department of Ophthalmology, Beijing Luhe Hospital, Capital Medical University, Beijing, China
| | - Panpan Yao
- Department of Ophthalmology Medicine, Wusong Branch, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xuqiang Lang
- Department of Ophthalmology, Beijing Luhe Hospital, Capital Medical University, Beijing, China
| | - Xue Li
- Department of Ophthalmology, Beijing Luhe Hospital, Capital Medical University, Beijing, China
| | - Dawei Zhang
- Department of Ophthalmology, Beijing Luhe Hospital, Capital Medical University, Beijing, China
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Liu Q, Guo L, Qi H, Lou M, Wang R, Hai B, Xu K, Zhu L, Ding Y, Li C, Xie L, Shen J, Xiang X, Shao J. A MYBL2 complex for RRM2 transactivation and the synthetic effect of MYBL2 knockdown with WEE1 inhibition against colorectal cancer. Cell Death Dis 2021; 12:683. [PMID: 34234118 PMCID: PMC8263627 DOI: 10.1038/s41419-021-03969-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 12/22/2022]
Abstract
Ribonucleotide reductase (RR) is a unique enzyme for the reduction of NDPs to dNDPs, the building blocks for DNA synthesis and thus essential for cell proliferation. Pan-cancer profiling studies showed that RRM2, the small subunit M2 of RR, is abnormally overexpressed in multiple types of cancers; however, the underlying regulatory mechanisms in cancers are still unclear. In this study, through searching in cancer-omics databases and immunohistochemistry validation with clinical samples, we showed that the expression of MYBL2, a key oncogenic transcriptional factor, was significantly upregulated correlatively with RRM2 in colorectal cancer (CRC). Ectopic expression and knockdown experiments indicated that MYBL2 was essential for CRC cell proliferation, DNA synthesis, and cell cycle progression in an RRM2-dependent manner. Mechanistically, MYBL2 directly bound to the promoter of RRM2 gene and promoted its transcription during S-phase together with TAF15 and MuvB components. Notably, knockdown of MYBL2 sensitized CRC cells to treatment with MK-1775, a clinical trial drug for inhibition of WEE1, which is involved in a degradation pathway of RRM2. Finally, mouse xenograft experiments showed that the combined suppression of MYBL2 and WEE1 synergistically inhibited CRC growth with a low systemic toxicity in vivo. Therefore, we propose a new regulatory mechanism for RRM2 transcription for CRC proliferation, in which MYBL2 functions by constituting a dynamic S-phase transcription complex following the G1/early S-phase E2Fs complex. Doubly targeting the transcription and degradation machines of RRM2 could produce a synthetic inhibitory effect on RRM2 level with a novel potential for CRC treatment.
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Affiliation(s)
- Qian Liu
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lijuan Guo
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Hongyan Qi
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang University Cancer Center, Key Laboratory of Disease Proteomics of Zhejiang Province, Key Laboratory of Cancer Prevention and Intervention of China National Ministry of Education, Zhejiang University School of Medicine, Hangzhou, China
| | - Meng Lou
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang University Cancer Center, Key Laboratory of Disease Proteomics of Zhejiang Province, Key Laboratory of Cancer Prevention and Intervention of China National Ministry of Education, Zhejiang University School of Medicine, Hangzhou, China
| | - Rui Wang
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Boning Hai
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Kailun Xu
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang University Cancer Center, Key Laboratory of Disease Proteomics of Zhejiang Province, Key Laboratory of Cancer Prevention and Intervention of China National Ministry of Education, Zhejiang University School of Medicine, Hangzhou, China
| | - Lijun Zhu
- Key Laboratory of Pancreatic Disease of Zhejiang Province, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yongfeng Ding
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Pancreatic Disease of Zhejiang Province, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Chen Li
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Lingdan Xie
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang University Cancer Center, Key Laboratory of Disease Proteomics of Zhejiang Province, Key Laboratory of Cancer Prevention and Intervention of China National Ministry of Education, Zhejiang University School of Medicine, Hangzhou, China
| | - Jing Shen
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang University Cancer Center, Key Laboratory of Disease Proteomics of Zhejiang Province, Key Laboratory of Cancer Prevention and Intervention of China National Ministry of Education, Zhejiang University School of Medicine, Hangzhou, China
| | - Xueping Xiang
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Zhejiang University Cancer Center, Key Laboratory of Disease Proteomics of Zhejiang Province, Key Laboratory of Cancer Prevention and Intervention of China National Ministry of Education, Zhejiang University School of Medicine, Hangzhou, China.
| | - Jimin Shao
- Department of Pathology & Pathophysiology, and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Zhejiang University Cancer Center, Key Laboratory of Disease Proteomics of Zhejiang Province, Key Laboratory of Cancer Prevention and Intervention of China National Ministry of Education, Zhejiang University School of Medicine, Hangzhou, China.
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Lin ZP, Al Zouabi NN, Xu ML, Bowen NE, Wu TL, Lavi ES, Huang PH, Zhu YL, Kim B, Ratner ES. In silico screening identifies a novel small molecule inhibitor that counteracts PARP inhibitor resistance in ovarian cancer. Sci Rep 2021; 11:8042. [PMID: 33850183 PMCID: PMC8044145 DOI: 10.1038/s41598-021-87325-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 03/22/2021] [Indexed: 12/20/2022] Open
Abstract
Poly ADP-ribose polymerase (PARP) inhibitors are promising targeted therapy for epithelial ovarian cancer (EOC) with BRCA mutations or defective homologous recombination (HR) repair. However, reversion of BRCA mutation and restoration of HR repair in EOC lead to PARP inhibitor resistance and reduced clinical efficacy of PARP inhibitors. We have previously shown that triapine, a small molecule inhibitor of ribonucleotide reductase (RNR), impaired HR repair and sensitized HR repair-proficient EOC to PARP inhibitors. In this study, we performed in silico screening of small molecule libraries to identify novel compounds that bind to the triapine-binding pocket on the R2 subunit of RNR and inhibit RNR in EOC cells. Following experimental validation of selected top-ranking in silico hits for inhibition of dNTP and DNA synthesis, we identified, DB4, a putative RNR pocket-binding inhibitor markedly abrogated HR repair and sensitized BRCA-wild-type EOC cells to the PARP inhibitor olaparib. Furthermore, we demonstrated that the combination of DB4 and olaparib deterred the progression of BRCA-wild type EOC xenografts and significantly prolonged the survival time of tumor-bearing mice. Herein we report the discovery of a putative small molecule inhibitor of RNR and HR repair for combination with PARP inhibitors to treat PARP inhibitor-resistant and HR repair-proficient EOC.
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Affiliation(s)
- Z Ping Lin
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA.
| | - Nour N Al Zouabi
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Mark L Xu
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Nicole E Bowen
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Terence L Wu
- Yale West Campus Analytical Core, Yale University, West Haven, CT, 06516, USA
| | - Ethan S Lavi
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Pamela H Huang
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Yong-Lian Zhu
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Baek Kim
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
- Center for Drug Discovery, Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Elena S Ratner
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA.
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Kadioglu O, Saeed M, Mahmoud N, Azawi S, Mrasek K, Liehr T, Efferth T. Identification of potential novel drug resistance mechanisms by genomic and transcriptomic profiling of colon cancer cells with p53 deletion. Arch Toxicol 2021; 95:959-974. [PMID: 33515271 PMCID: PMC7904745 DOI: 10.1007/s00204-021-02979-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/04/2021] [Indexed: 12/25/2022]
Abstract
TP53 (p53) is a pivotal player in tumor suppression with fifty percent of all invasive tumors displaying mutations in the TP53 gene. In the present study, we characterized colon cancer cells (HCT116 p53 −/−) with TP53 deletion, a sub-line derived from HCT116-p53 +/+ cells. RNA sequencing and network analyses were performed to identify novel drug resistance mechanisms. Chromosomal aberrations were identified by multicolor fluorescence in situ hybridization (mFISH) and array comparative genomic hybridization (aCGH). Numerous genes were overexpressed in HCT116 p53 −/− cells: RND3/RhoE (235.6-fold up-regulated), DCLK1 (60.2-fold up-regulated), LBH (31.9-fold up-regulated), MYB (28.9-fold up-regulated), TACSTD2 (110.1-fold down-regulated), NRIP1 (81.5-fold down-regulated) and HLA-DMB (69.7-fold down-regulated) are among the identified genes with potential influence on multidrug resistance (MDR) and they are associated with cancer progression and tumorigenesis, according to previously published studies. Probably due to TP53 deletion, disturbances in DNA repair and apoptosis are leading to aberrancies in cellular and organismal organization, ultimately increasing tumorigenesis and cancer progression potential. With NFκB, PI3K and HSP70, being at the center of merged protein network, and TH1-2 pathways, being among the influenced pathways, it can be speculated that the inflammatory pathway contributes to a resistance phenotype together with cell cycle regulation and heat-shock response. HCT116-p53 −/− cells have more chromosomal aberrations, gains and losses in copy numbers than HCT116-p53 +/+ cells. In conclusion, numerous genomic aberrations, which might be associated with yet unknown drug resistance mechanisms, were identified. This may have important implications for future treatment strategies.
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Affiliation(s)
- Onat Kadioglu
- Department of Pharmaceutical Biology, Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg University, Mainz, Germany
| | - Mohamed Saeed
- Department of Pharmaceutical Biology, Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg University, Mainz, Germany
| | - Nuha Mahmoud
- Department of Pharmaceutical Biology, Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg University, Mainz, Germany
| | - Shaymaa Azawi
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Kristin Mrasek
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Thomas Liehr
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Thomas Efferth
- Department of Pharmaceutical Biology, Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg University, Mainz, Germany.
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Jin CY, Du L, Nuerlan AH, Wang XL, Yang YW, Guo R. High expression of RRM2 as an independent predictive factor of poor prognosis in patients with lung adenocarcinoma. Aging (Albany NY) 2020; 13:3518-3535. [PMID: 33411689 PMCID: PMC7906179 DOI: 10.18632/aging.202292] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 10/27/2020] [Indexed: 12/24/2022]
Abstract
Ribonucleotide reductase subunit M2 may play a role as a potential prognostic biomarker in several cancers. In this study, we evaluated whether RRM2 gene expression is associated with the prognosis of patients with lung adenocarcinoma (LUAD) using publicly available data from The Cancer Genome Atlas (TCGA). Wilcoxon signed-rank test and logistic regression were performed to evaluate the association between RRM2 expression and clinical features in patients with LUAD. Kaplan-Meier and Cox regression methods were used to examine the effect of RRM2 expression level in the overall survival, and a nomogram was performed to illustrate the correlation between the RRM2 gene expression and the risk of LUAD. TCGA data set was used for gene set enrichment analysis (GSEA). We also performed a further experiment in vitro to assess the effect of RRM2 expression on the proliferation and invasive abilities of LUAD cells and its key signaling pathway proteins. Our results revealed that the expression level of RRM2 in patients with LUAD was much higher than that in normal tissues (p = 3.99e-32). High expression of RRM2 was significantly associated with tumor stage (IV vs. I: OR = 3.02, p = 0.012) and TNM classification (T2 vs. T1: OR = 1.88, p = 0.001; N2 vs. N0: OR = 2.69, p < 0.001). Kaplan-Meier survival analysis showed that high expression of RRM2 was associated with a worse prognosis of LUAD compared low expression of RRM2 (p = 7.86e-04). Multivariate analysis showed that high RRM2 expression was an independent factor affecting overall survival (HR = 1.29, p < 0.001). The association between RRM2 gene expression and the risk of LUAD was presented in a nomogram. GSEA revealed that the cell cycle, p53 signaling pathway, DNA replication, small cell lung cancer, apoptosis, and pathways in cancer were differentially enriched in patients with high expression of RRM2. RRM2 over-expression promoted the proliferation and invasive abilities of LUAD cells. RRM2 over-expression increased the activation of Bcl-2 and E-cadherin signaling pathways, and reduced the activation of p53 signaling pathway. In summary, high RRM2 expression is an independent predictive factor of poor prognosis in patients with lung adenocarcinoma.
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Affiliation(s)
- Cheng-Yu Jin
- Department of Chest Surgery, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi 830001, Xinjiang, China
| | - Liang Du
- Department of Chest Surgery, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi 830001, Xinjiang, China
| | - A-Han Nuerlan
- Department of Chest Surgery, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi 830001, Xinjiang, China
| | - Xiao-Lei Wang
- Department of Chest Surgery, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi 830001, Xinjiang, China
| | - Yong-Wei Yang
- Department of Chest Surgery, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi 830001, Xinjiang, China
| | - Rui Guo
- Department of Chest Surgery, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi 830001, Xinjiang, China
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Yang Y, Lin J, Guo S, Xue X, Wang Y, Qiu S, Cui J, Ma L, Zhang X, Wang J. RRM2 protects against ferroptosis and is a tumor biomarker for liver cancer. Cancer Cell Int 2020; 20:587. [PMID: 33372599 PMCID: PMC7720568 DOI: 10.1186/s12935-020-01689-8] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 11/30/2020] [Indexed: 12/13/2022] Open
Abstract
Background Ferroptosis is the process of cell death triggered by lipid peroxides, and inhibition of glutathione (GSH) synthesis leads to ferroptosis. Liver cancer progression is closely linked to ferroptosis suppression. However, the mechanism by which inhibition of GSH synthesis suppresses potential ferroptosis of liver cancer cells and whether ferroptosis-related liver cancer biomarkers have a promising diagnostic value remain unknown. Methods Ribonucleotide reductase regulatory subunit M2 (RRM2) levels were measured using an enzyme linked immunosorbent assay (ELISA), quantitative RT-PCR (qPCR), immunoblotting (IB) and immunochemistry (IHC). Cell viability and cell death were measured by a CellTiter-Glo luminescent cell viability assay and staining with SYTOX Green followed by flow cytometry, respectively. Metabolites were measured using the indicated kits. The Interaction between glutathione synthetase (GSS) and RRM2 was measured using immunofluorescence (IF), co-immunoprecipitation (co-IP) and the proximal ligation assay (PLA). The diagnostic value was analyzed using the area under the receiver operating characteristic curve (AUC-ROC). Bioinformatics analysis was performed using the indicated database. Results RRM2 showed specifically elevated levels in liver cancer and inhibited ferroptosis by stimulating GSH synthesis via GSS. Mechanistically, phosphorylation of RRM2 at the Threonine 33 residue (T33) was maintained at normal levels to block the RRM2–GSS interaction and therefore protected RRM2 and GSS from further proteasome degradation. However, under ferroptotic stress, RRM2 was dephosphorylated at T33, thus the RRM2–GSS interaction was promoted. This resulted in the translocation of RRM2 and GSS to the proteasome for simultaneous degradation. Clinically, serum RRM2 was significantly associated with serum alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (γ-GT), albumin (ALB) and total bilirubin. The AUC-ROC for the combination of RRM2 with AFP was 0.947, with a sensitivity of 88.7% and a specificity of 97.0%, which indicates better diagnostic performance compared to either RRM2 or AFP alone. Conclusion RRM2 exerts an anti-ferroptotic role in liver cancer cells by sustaining GSH synthesis. Serum RRM2 will be useful as a biomarker to evaluate the degree to which ferroptosis is suppressed and improve diagnostic efficiency for liver cancer.
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Affiliation(s)
- Yueyue Yang
- Department of Clinical Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Jiafei Lin
- Department of Clinical Laboratory, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Susu Guo
- Department of Clinical Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Xiangfei Xue
- Department of Clinical Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Yikun Wang
- Shanghai Institute of Thoracic Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Shiyu Qiu
- Shanghai Institute of Thoracic Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Jiangtao Cui
- Shanghai Institute of Thoracic Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Lifang Ma
- Shanghai Institute of Thoracic Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Xiao Zhang
- Shanghai Institute of Thoracic Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, 200030, China. .,Department of Thoracic Surgery, Shanghai Institute of Thoracic Tumors, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 Huaihai West Road, Shanghai, 200030, China.
| | - Jiayi Wang
- Department of Clinical Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai, 200072, China. .,Shanghai Institute of Thoracic Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, 200030, China. .,Department of Thoracic Surgery, Shanghai Institute of Thoracic Tumors, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 Huaihai West Road, Shanghai, 200030, China.
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Inhibiting RRM2 to enhance the anticancer activity of chemotherapy. Biomed Pharmacother 2020; 133:110996. [PMID: 33227712 DOI: 10.1016/j.biopha.2020.110996] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 10/28/2020] [Accepted: 11/01/2020] [Indexed: 12/13/2022] Open
Abstract
RRM2, the small subunit of ribonucleotide reductase, is identified as a tumor promotor and therapeutic target. It is common to see the overexpression of RRM2 in chemo-resistant cancer cells and patients. RRM2 mediates the resistance of many chemotherapeutic drugs and could become the predictor for chemosensitivity and prognosis. Therefore, inhibition of RRM2 may be an effective means to enhance the anticancer activity of chemotherapy. This review tries to discuss the mechanisms of RRM2 overexpression and the role of RRM2 in resistance to chemotherapy. Additionally, we compile the studies on small interfering RNA targets RRM2, RRM2 inhibitors, kinase inhibitors, and other ways that could overcome the resistance of chemotherapy or exert synergistic anticancer activity with chemotherapy through the expression inhibition or the enzyme inactivation of RRM2.
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Silasi M, You Y, Simpson S, Kaislasuo J, Pal L, Guller S, Peng G, Ramhorst R, Grasso E, Etemad S, Durosier S, Aldo P, Mor G. Human Chorionic Gonadotropin modulates CXCL10 Expression through Histone Methylation in human decidua. Sci Rep 2020; 10:5785. [PMID: 32238853 PMCID: PMC7113245 DOI: 10.1038/s41598-020-62593-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/12/2020] [Indexed: 12/20/2022] Open
Abstract
The process of implantation, trophoblast invasion and placentation demand continuous adaptation and modifications between the trophoblast (embryonic) and the decidua (maternal). Within the decidua, the maternal immune system undergoes continued changes, as the pregnancy progress, in terms of the cell population, phenotype and production of immune factors, cytokines and chemokines. Human chorionic gonadotropin (hCG) is one of the earliest hormones produced by the blastocyst and has potent immune modulatory effects, especially in relation to T cells. We hypothesized that trophoblast-derived hCG modulates the immune population present at the maternal fetal interface by modifying the cytokine profile produced by the stromal/decidual cells. Using in vitro models from decidual samples we demonstrate that hCG inhibits CXCL10 expression by inducing H3K27me3 histone methylation, which binds to Region 4 of the CXCL10 promoter, thereby suppressing its expression. hCG-induced histone methylation is mediated through EZH2, a functional member of the PRC2 complex. Regulation of CXCL10 expression has a major impact on the capacity of endometrial stromal cells to recruit CD8 cells. We demonstrate the existence of a cross talk between the placenta (hCG) and the decidua (CXCL10) in the control of immune cell recruitment. Alterations in this immune regulatory function, such as during infection, will have detrimental effects on the success of the pregnancy.
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Affiliation(s)
- Michelle Silasi
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
| | - Yuan You
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
- C.S. Mott Center for Human Growth and Development, Department of Obstetrics, Gynecology, Wayne State University, Detroit, MI, USA
| | - Samantha Simpson
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
| | - Janina Kaislasuo
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
- Department of Obstetrics and Gynecology, University of Helsinki and the Helsinki University Hospital, Helsinki, Finland
| | - Lubna Pal
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
| | - Seth Guller
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
| | - Gang Peng
- Department of Biostatistics, School of Public Health, Yale University, New Haven, CT, USA
| | - Rosanna Ramhorst
- Laboratory of Immunopharmacology, University of Buenos Aires School of Sciences, IQUIBICEN-CONICET (National Research Council), Buenos Aires, Argentina
| | - Esteban Grasso
- Laboratory of Immunopharmacology, University of Buenos Aires School of Sciences, IQUIBICEN-CONICET (National Research Council), Buenos Aires, Argentina
| | - Shervin Etemad
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
| | - Sandy Durosier
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
| | - Paulomi Aldo
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA
| | - Gil Mor
- Yale University School of Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, CT, USA.
- C.S. Mott Center for Human Growth and Development, Department of Obstetrics, Gynecology, Wayne State University, Detroit, MI, USA.
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Yang D, He Y, Wu B, Deng Y, Wang N, Li M, Liu Y. Integrated bioinformatics analysis for the screening of hub genes and therapeutic drugs in ovarian cancer. J Ovarian Res 2020; 13:10. [PMID: 31987036 PMCID: PMC6986075 DOI: 10.1186/s13048-020-0613-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 01/20/2020] [Indexed: 02/06/2023] Open
Abstract
Background Ovarian cancer (OC) ranks fifth as a cause of gynecological cancer-associated death globally. Until now, the molecular mechanisms underlying the tumorigenesis and prognosis of OC have not been fully understood. This study aims to identify hub genes and therapeutic drugs involved in OC. Methods Four gene expression profiles (GSE54388, GSE69428, GSE36668, and GSE40595) were downloaded from the Gene Expression Omnibus (GEO), and the differentially expressed genes (DEGs) in OC tissues and normal tissues with an adjusted P-value < 0.05 and a |log fold change (FC)| > 1.0 were first identified by GEO2R and FunRich software. Next, Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) analyses were performed for functional enrichment analysis of these DEGs. Then, the hub genes were identified by the cytoHubba plugin and the other bioinformatics approaches including protein-protein interaction (PPI) network analysis, module analysis, survival analysis, and miRNA-hub gene network construction was also performed. Finally, the GEPIA2 and DGIdb databases were utilized to verify the expression levels of hub genes and to select the candidate drugs for OC, respectively. Results A total of 171 DEGs were identified, including 114 upregulated and 57 downregulated DEGs. The results of the GO analysis indicated that the upregulated DEGs were mainly involved in cell division, nucleus, and protein binding, whereas the biological functions showing enrichment in the downregulated DEGs were mainly negative regulation of transcription from RNA polymerase II promoter, protein complex and apicolateral plasma membrane, and glycosaminoglycan binding. As for the KEGG-pathway, the upregulated DEGs were mainly associated with metabolic pathways, biosynthesis of antibiotics, biosynthesis of amino acids, cell cycle, and HTLV-I infection. Additionally, 10 hub genes (KIF4A, CDC20, CCNB2, TOP2A, RRM2, TYMS, KIF11, BIRC5, BUB1B, and FOXM1) were identified and survival analysis of these hub genes showed that OC patients with the high-expression of CCNB2, TYMS, KIF11, KIF4A, BIRC5, BUB1B, FOXM1, and CDC20 were statistically more likely to have poorer progression free survival. Meanwhile, the expression levels of the hub genes based on GEPIA2 were in accordance with those based on GEO. Finally, DGIdb database was used to identify 62 small molecules as the potentially targeted drugs for OC treatment. Conclusions In summary, the data may produce new insights regarding OC pathogenesis and treatment. Hub genes and candidate drugs may improve individualized diagnosis and therapy for OC in future.
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Affiliation(s)
- Dan Yang
- Department of Environmental Health, School of Public Health, China Medical University, 77th Puhe Road, Shenyang, 110122, Liaoning, China
| | - Yang He
- Department of Central Laboratory, The First Affiliated Hospital, China Medical University, 155th Nanjing North Street, Shenyang, 110001, Liaoning, China
| | - Bo Wu
- Department of Anus and Intestine Surgery, The First Affiliated Hospital, China Medical University, 155th Nanjing North Street, Shenyang, 110001, Liaoning, China
| | - Yan Deng
- Department of Environmental Health, School of Public Health, China Medical University, 77th Puhe Road, Shenyang, 110122, Liaoning, China
| | - Nan Wang
- Department of Environmental Health, School of Public Health, China Medical University, 77th Puhe Road, Shenyang, 110122, Liaoning, China
| | - Menglin Li
- Department of Environmental Health, School of Public Health, China Medical University, 77th Puhe Road, Shenyang, 110122, Liaoning, China
| | - Yang Liu
- Department of Environmental Health, School of Public Health, China Medical University, 77th Puhe Road, Shenyang, 110122, Liaoning, China.
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12
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Okonska A, Bühler S, Rao V, Ronner M, Blijlevens M, van der Meulen-Muileman IH, de Menezes RX, Wipplinger M, Oehl K, Smit EF, Weder W, Stahel RA, Penengo L, van Beusechem VW, Felley-Bosco E. Functional Genomic Screen in Mesothelioma Reveals that Loss of Function of BRCA1-Associated Protein 1 Induces Chemoresistance to Ribonucleotide Reductase Inhibition. Mol Cancer Ther 2019; 19:552-563. [PMID: 31619462 DOI: 10.1158/1535-7163.mct-19-0356] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 09/06/2019] [Accepted: 10/10/2019] [Indexed: 11/16/2022]
Abstract
Loss of function of BRCA1-associated protein 1 (BAP1) is observed in about 50% of malignant pleural mesothelioma (MPM) cases. The aim of this study was to investigate whether this aspect could be exploited for targeted therapy. A genetically engineered model was established expressing either functional or nonfunctional BAP1, and whole-genome siRNA synthetic lethality screens were performed assessing differentially impaired survival between the two cell lines. The whole-genome siRNA screen unexpectedly revealed 11 hits (FDR < 0.05) that were more cytotoxic to BAP1-proficient cells. Two actionable targets, ribonucleotide reductase (RNR) catalytic subunit M1 (RRM1) and RNR regulatory subunit M2 (RRM2), were validated. In line with the screen results, primary mesothelioma (BAP1 +/-) overexpressing BAP1 C91A (catalytically dead mutant) was more resistant to RNR inhibition, while BAP1 knockdown in the BAP1-proficient cell lines rescued the cells from their vulnerability to RNR depletion. Gemcitabine and hydroxyurea were more cytotoxic in BAP1-proficient cell line-derived spheroids compared with BAP1 deficient. Upregulation of RRM2 upon gemcitabine and hydroxyurea treatment was more profound in BAP1 mut/del cell lines. Increased lethality mediated by RNR inhibition was observed in NCI-H2452 cells reconstituted with BAP1-WT but not with BAP1 C91A. Upregulation of RRM2 in NCI-H2452-BAP1 WT spheroids was modest compared with control or C91A mutant. Together, we found that BAP1 is involved in the regulation of RNR levels during replication stress. Our observations reveal a potential clinical application where BAP1 status could serve as predictive or stratification biomarker for RNR inhibition-based therapy in MPM.
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Affiliation(s)
- Agata Okonska
- Laboratory of Molecular Oncology, Lungen- und Thoraxonkologie Zentrum, University Hospital Zürich, Zürich, Switzerland
| | - Saskja Bühler
- Laboratory of Molecular Oncology, Lungen- und Thoraxonkologie Zentrum, University Hospital Zürich, Zürich, Switzerland
| | - Vasundhara Rao
- Laboratory of Molecular Oncology, Lungen- und Thoraxonkologie Zentrum, University Hospital Zürich, Zürich, Switzerland
| | - Manuel Ronner
- Laboratory of Molecular Oncology, Lungen- und Thoraxonkologie Zentrum, University Hospital Zürich, Zürich, Switzerland
| | - Maxime Blijlevens
- Amsterdam UMC, Vrije Universiteit Amsterdam, Medical Oncology, Cancer Center Amsterdam, Amsterdam, the Netherlands
| | | | - Renee X de Menezes
- Amsterdam UMC, Vrije Universiteit Amsterdam, Epidemiology and Biostatistics, Cancer Center Amsterdam, Amsterdam, the Netherlands
| | - Martin Wipplinger
- Laboratory of Molecular Oncology, Lungen- und Thoraxonkologie Zentrum, University Hospital Zürich, Zürich, Switzerland
| | - Kathrin Oehl
- Institute of Pathology and Molecular Pathology, University Hospital Zürich, Zürich, Switzerland
| | - Egbert F Smit
- Department of Thoracic Surgery, NKI, Amsterdam, the Netherlands
| | - Walter Weder
- Department of Thoracic Surgery, University Hospital Zürich, Zürich, Switzerland
| | - Rolf A Stahel
- Lungen- und Thoraxonkologie Zentrum, University Hospital Zürich, 8091 Zürich, Switzerland
| | - Lorenza Penengo
- Institute of Molecular Cancer Research, University of Zürich, Zürich, Switzerland
| | - Victor W van Beusechem
- Amsterdam UMC, Vrije Universiteit Amsterdam, Medical Oncology, Cancer Center Amsterdam, Amsterdam, the Netherlands
| | - Emanuela Felley-Bosco
- Laboratory of Molecular Oncology, Lungen- und Thoraxonkologie Zentrum, University Hospital Zürich, Zürich, Switzerland.
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13
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Liu X, Peng J, Zhou Y, Xie B, Wang J. Silencing RRM2 inhibits multiple myeloma by targeting the Wnt/β‑catenin signaling pathway. Mol Med Rep 2019; 20:2159-2166. [PMID: 31322175 PMCID: PMC6691237 DOI: 10.3892/mmr.2019.10465] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 05/29/2019] [Indexed: 12/22/2022] Open
Abstract
Ribonucleotide reductase M2 (RRM2) is one of the two subunits that comprise ribonucleotide reductase (RR), the enzyme that catalyzes the conversion of ribonucleotide 5'‑diphosphates into 2'‑deoxyribonucleotides, which are required for DNA synthesis. RRM2 is a stress response factor important for the development of several tumors. However, its role in multiple myeloma (MM) remains to be fully elucidated. The present study aimed to investigate the role of RRM2 in MM. The expression of RRM2 in patients with MM was analyzed using the Oncomine database. The results demonstrated that RRM2 expression was higher in MM compared with healthy subjects. Reverse transcription‑quantitative polymerase chain reaction and western blot results revealed that RRM2 expression was decreased following transfection with a small interfering RNA targeting RRM2 into NCI‑H929 cells. RR activity and Cell Counting Kit‑8 assays demonstrated that RRM2 silencing reduced RR activity and inhibited cell proliferation. Annexin V‑propidium iodide staining indicated that the percentage of apoptotic NCI‑H929 cells was increased following RRM2 silencing compared with that in the control group. Increased phosphorylation of H2AX indicated that RRM2 silencing may activate the DNA‑damage response pathway in NCI‑H929 cells. Western blot analysis revealed that protein levels of the apoptosis‑associated factor Bcl‑2 were reduced, whereas Bax, cleaved caspase‑3 and cleaved poly(ADP‑ribose) polymerase 1 were upregulated following RRM2 silencing compared with the control group. In addition, the results demonstrated that RRM2 silencing may inhibit target gene expression in the Wnt/β‑catenin signaling pathway by increasing the phosphorylation of glucose synthase kinase 3β. These findings indicated that RRM2 may be involved in the proliferation and apoptosis of MM cells via the Wnt/β‑catenin signaling pathway, suggesting that RRM2 may represent a novel therapeutic target for MM.
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Affiliation(s)
- Xia Liu
- Central Laboratory, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310005, P.R. China
| | - Jiamin Peng
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310005, P.R. China
| | - Yayun Zhou
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310005, P.R. China
| | - Bei Xie
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310005, P.R. China
| | - Jianchao Wang
- Department of Clinical Laboratory, Zhejiang Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang 310012, P.R. China
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14
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Lin ZP, Zhu YL, Lo YC, Moscarelli J, Xiong A, Korayem Y, Huang PH, Giri S, LoRusso P, Ratner ES. Combination of triapine, olaparib, and cediranib suppresses progression of BRCA-wild type and PARP inhibitor-resistant epithelial ovarian cancer. PLoS One 2018; 13:e0207399. [PMID: 30444904 PMCID: PMC6239325 DOI: 10.1371/journal.pone.0207399] [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: 07/23/2018] [Accepted: 10/30/2018] [Indexed: 12/14/2022] Open
Abstract
PARP inhibitors target BRCA mutations and defective homologous recombination repair (HRR) for the treatment of epithelial ovarian cancer (EOC). However, the treatment of HRR-proficient EOC with PARP inhibitors remains challenging. The objective of this study was to determine whether the combination of triapine (ribonucleotide reductase inhibitor), cediranib (vascular endothelial growth factor receptor tyrosine kinase inhibitor), and the PARP inhibitor olaparib synergized against BRCA wild-type and HRR-proficient EOC in xenograft mouse models. In addition, the mechanisms by which cediranib augmented the efficacy of triapine and olaparib were investigated. BRCA-wild type and PARP inhibitor-resistant EOC cell lines were implanted subcutaneously (s.c.) into nude mice or injected intraperitoneally (i.p.) into SCID-Beige mice. Mice were then treated i.p. with olaparib, cediranib, triapine, various double and triple combinations. The volume of s.c tumor in nude mice and the abdominal circumference of SCID-Beige mice were measured to evaluate the effectiveness of the treatment to delay tumor growth and prolong the survival time of mice. In both xenograft mouse models, the combination of triapine, olaparib and cediranib resulted in marked suppression of BRCA-wild type EOC growth and significant prolongation of the survival time of mice, with efficacy greater than any double combinations and single drugs. Furthermore, we identified that cediranib abrogated pro-survival and anti-apoptotic AKT signaling, thereby enhancing the efficacy of triapine and olaparib against BRCA-wild type EOC cells. Taken together, our results demonstrate a proof-of-principle approach and the combination regiment holds promise in treating BRCA-wild type and PARP inhibitor-resistant EOC.
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Affiliation(s)
- Z. Ping Lin
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, United States of America
- * E-mail: (ESR); (ZPL)
| | - Yong-Lian Zhu
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Ying-Chun Lo
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Jake Moscarelli
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Amy Xiong
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Yasmin Korayem
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Pamela H. Huang
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Smith Giri
- Section of Medical Oncology, Yale Cancer Center, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Patricia LoRusso
- Section of Medical Oncology, Yale Cancer Center, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Elena S. Ratner
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, United States of America
- * E-mail: (ESR); (ZPL)
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15
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Lin ZP, Zhu YL, Ratner ES. Targeting Cyclin-Dependent Kinases for Treatment of Gynecologic Cancers. Front Oncol 2018; 8:303. [PMID: 30135856 PMCID: PMC6092490 DOI: 10.3389/fonc.2018.00303] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/19/2018] [Indexed: 02/01/2023] Open
Abstract
Ovarian, uterine/endometrial, and cervical cancers are major gynecologic malignancies estimated to cause nearly 30,000 deaths in 2018 in US. Defective cell cycle regulation is the hallmark of cancers underpinning the development and progression of the disease. Normal cell cycle is driven by the coordinated and sequential rise and fall of cyclin-dependent kinases (CDK) activity. The transition of cell cycle phases is governed by the respective checkpoints that prevent the entry into the next phase until cellular or genetic defects are repaired. Checkpoint activation is achieved by p53- and ATM/ATR-mediated inactivation of CDKs in response to DNA damage. Therefore, an aberrant increase in CDK activity and/or defects in checkpoint activation lead to unrestricted cell cycle phase transition and uncontrolled proliferation that give rise to cancers and perpetuate malignant progression. Given that CDK activity is also required for homologous recombination (HR) repair, pharmacological inhibition of CDKs can be exploited as a synthetic lethal approach to augment the therapeutic efficacy of PARP inhibitors and other DNA damaging modalities for the treatment of gynecologic cancers. Here, we overview the basic of cell cycle and discuss the mechanistic studies that establish the intimate link between CDKs and HR repair. In addition, we present the perspective of preclinical and clinical development in small molecule inhibitors of CDKs and CDK-associated protein targets, as well as their potential use in combination with hormonal therapy, PARP inhibitors, chemotherapy, and radiation to improve treatment outcomes.
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Affiliation(s)
- Z Ping Lin
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, United States
| | - Yong-Lian Zhu
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, United States
| | - Elena S Ratner
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, United States
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16
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Gemcitabine resistance mediated by ribonucleotide reductase M2 in lung squamous cell carcinoma is reversed by GW8510 through autophagy induction. Clin Sci (Lond) 2018; 132:1417-1433. [PMID: 29853661 DOI: 10.1042/cs20180010] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 05/13/2018] [Accepted: 05/25/2018] [Indexed: 12/28/2022]
Abstract
Although chemotherapeutic regimen containing gemcitabine is the first-line therapy for advanced lung squamous cell carcinoma (LSCC), gemcitabine resistance remains an important clinical problem. Some studies suggest that overexpressions of ribonucleotide reductase (RNR) subunit M2 (RRM2) may be involved in gemcitabine resistance. We used a novel RRM2 inhibitor, GW8510, as a gemcitabine sensitization agent to investigate the therapeutic utility in reversing gemcitabine resistance in LSCC. Results showed that the expressions of RRM2 were increased in gemcitabine intrinsic resistant LSCC cells upon gemcitabine treatment. GW8510 not only suppressed LSCC cell survival, but also sensitized gemcitabine-resistant cells to gemcitabine through autophagy induction mediated by RRM2 down-regulation along with decrease in dNTP levels. The combination of GW8510 and gemcitabine produced a synergistic effect on killing LSCC cells. The synergism of the two agents was impeded by addition of autophagy inhibitors chloroquine (CQ) or bafilomycin A1 (Baf A1), or knockdown of the autophagy gene, Bcl-2-interacting protein 1 (BECN1). Moreover, GW8510-caused LSCC cell sensitization to gemcitabine through autophagy induction was parallel with impairment of DNA double-strand break (DSB) repair and marked increase in cell apoptosis, revealing a cross-talk between autophagy and DNA damage repair, and an interplay between autophagy and apoptosis. Finally, gemcitabine sensitization mediated by autophagy induction through GW8510-caused RRM2 down-regulation was demonstrated in vivo in gemcitabine-resistant LSCC tumor xenograft, further indicating that the sensitization is dependent on autophagy activation. In conclusion, GW8510 can reverse gemcitabine resistance in LSCC cells through RRM2 downregulation-mediated autophagy induction, and GW850 may be a promising therapeutic agent against LSCC as it combined with gemcitabine.
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17
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Kunos CA, Coleman CN. Current and Future Initiatives for Radiation Oncology at the National Cancer Institute in the Era of Precision Medicine. Int J Radiat Oncol Biol Phys 2018; 102:18-25. [PMID: 29325810 DOI: 10.1016/j.ijrobp.2017.02.225] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Revised: 02/07/2017] [Accepted: 02/28/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Charles A Kunos
- Cancer Therapy Evaluation Program, National Cancer Institute, Bethesda, Maryland.
| | - C Norman Coleman
- Radiation Research Program, National Cancer Institute, Bethesda, Maryland
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18
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The impact of replication stress on replication dynamics and DNA damage in vertebrate cells. Nat Rev Genet 2017; 18:535-550. [DOI: 10.1038/nrg.2017.46] [Citation(s) in RCA: 170] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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19
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Qu J, Sun W, Zhong J, Lv H, Zhu M, Xu J, Jin N, Xie Z, Tan M, Lin SH, Geng M, Ding J, Huang M. Phosphoglycerate mutase 1 regulates dNTP pool and promotes homologous recombination repair in cancer cells. J Cell Biol 2017; 216:409-424. [PMID: 28122957 PMCID: PMC5294784 DOI: 10.1083/jcb.201607008] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 11/02/2016] [Accepted: 01/17/2017] [Indexed: 02/04/2023] Open
Abstract
Phosphoglycerate mutase 1 (PGAM1) regulates metabolism in cancer cells. Qu et al. show that PGAM1 maintains the intracellular dNTP pool, promotes the stability of CTBP-interacting protein, and is required for homologous recombination repair. PGAM1 inhibition sensitizes BRCA1/2-proficient breast cancer to PARP inhibitors. Glycolytic enzymes are known to play pivotal roles in cancer cell survival, yet their molecular mechanisms remain poorly understood. Phosphoglycerate mutase 1 (PGAM1) is an important glycolytic enzyme that coordinates glycolysis, pentose phosphate pathway, and serine biosynthesis in cancer cells. Herein, we report that PGAM1 is required for homologous recombination (HR) repair of DNA double-strand breaks (DSBs) caused by DNA-damaging agents. Mechanistically, PGAM1 facilitates DSB end resection by regulating the stability of CTBP-interacting protein (CtIP). Knockdown of PGAM1 in cancer cells accelerates CtIP degradation through deprivation of the intracellular deoxyribonucleotide triphosphate pool and associated activation of the p53/p73 pathway. Enzymatic inhibition of PGAM1 decreases CtIP protein levels, impairs HR repair, and hence sensitizes BRCA1/2-proficient breast cancer to poly(ADP-ribose) polymerase (PARP) inhibitors. Together, this study identifies a metabolically dependent function of PGAM1 in promoting HR repair and reveals a potential therapeutic opportunity for PGAM1 inhibitors in combination with PARP inhibitors.
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Affiliation(s)
- Jia Qu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, China.,State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Wenyi Sun
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jie Zhong
- Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hao Lv
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Mingrui Zhu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jun Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Nan Jin
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Zuoquan Xie
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Minjia Tan
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Shu-Hai Lin
- Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Meiyu Geng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jian Ding
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, China .,State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Min Huang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
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Abstract
OBJECTIVES There is a need for validated predictive markers of gemcitabine response to guide precision medicine treatment in pancreatic cancer. We previously validated human equilibrative nucleoside transporter 1 as a predictive marker of gemcitabine treatment response using Radiation Therapy Oncology Group 9704. Controversy exists about the predictive value of gemcitabine metabolism pathway biomarkers: deoxycytidine kinase (DCK), ribonucleotide reductase 1 (RRM1), RRM2, and p53R2. METHODS Radiation Therapy Oncology Group 9704 prospectively randomized 538 patients after pancreatic resection to receive either 5-fluorouracil or gemcitabine. Tumor DCK, RRM1, RRM2, and p53R protein expressions were analyzed using a tissue microarray and immunohistochemistry and correlated with treatment outcome (overall survival and disease-free survival) by unconditional logistic regression analysis. RESULTS There were 229 patients eligible for analysis from both the 5-fluorouracil and gemcitabine arms. Only RRM2 protein expression, and not DCK, RRM1, or p53R2 protein expression, was associated with survival in the gemcitabine treatment arm. CONCLUSIONS Despite limited data from other nonrandomized treatment data, our data do not support the predictive value of DCK, RRM1, or p53R2. Efforts should focus on human equilibrative nucleoside transporter 1 and possibly RRM2 as valid predictive markers of the treatment response of gemcitabine in pancreatic cancer.
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Whicker ME, Lin ZP, Hanna R, Sartorelli AC, Ratner ES. MK-2206 sensitizes BRCA-deficient epithelial ovarian adenocarcinoma to cisplatin and olaparib. BMC Cancer 2016; 16:550. [PMID: 27465688 PMCID: PMC4964088 DOI: 10.1186/s12885-016-2598-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 07/21/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Platinum resistance is a major obstacle in the treatment of epithelial ovarian cancer (EOC). Activation of the AKT pathway promotes platinum resistance while inhibition of AKT sensitizes chemoresistant cells. Patients with BRCA mutant EOC, and thus a defect in the homologous recombination (HR) repair pathway, demonstrate greater clinical response to platinum and olaparib therapy than patients with BRCA wild-type EOC. MK-2206, an allosteric inhibitor of AKT phosphorylation, sensitizes a variety of cell types to various anticancer agents and is currently undergoing phase II trials as monotherapy for platinum-resistant ovarian, fallopian tube, and peritoneal cancer. This study examines the differential effects of AKT inhibition with cisplatin and olaparib therapy in BRCA1/2-deficient versus wild-type EOC. METHODS PEO1, a chemosensitive BRCA2-mutant serous ovarian adenocarcinoma, and PEO4, a reverted BRCA2-proficient line from the same patient after the development of chemotherapeutic resistance, were primarily used for the study. In PEO1, MK-2206 demonstrated moderate to strong synergism with cisplatin and olaparib at all doses, while demonstrating antagonism at all doses in PEO4. RESULTS Baseline phospho-AKT activity in untreated cells was upregulated in both BRCA1- and 2-deficient cell lines. MK-2206 prevented cisplatin- and olaparib-induced AKT activation in the BRCA2-deficient PEO1 cells. We propose that BRCA-deficient EOC cells upregulate baseline AKT activity to enhance survival in the absence of HR. Higher AKT activity is also required to withstand cytotoxic agent-induced DNA damage, leading to strong synergism between MK-2206 and cisplatin or olaparib therapy in BRCA-deficient cells. CONCLUSIONS MK-2206 shows promise as a chemosensitization agent in BRCA-deficient EOC and merits clinical investigation in this patient population.
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Affiliation(s)
- Margaret E Whicker
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, USA.
| | - Z Ping Lin
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, USA
| | - Ruth Hanna
- Section of Gynecologic Oncology, Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, USA
| | - Alan C Sartorelli
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, USA
| | - Elena S Ratner
- Section of Gynecologic Oncology, Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, USA
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Takebe N, Ahmed MM, Vikram B, Bernhard EJ, Zwiebel J, Norman Coleman C, Kunos CA. Radiation-Therapeutic Agent Clinical Trials: Leveraging Advantages of a National Cancer Institute Programmatic Collaboration. Semin Radiat Oncol 2016; 26:271-80. [PMID: 27619249 DOI: 10.1016/j.semradonc.2016.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A number of oncology phase II radiochemotherapy trials with promising results have been conducted late in the overall experimental therapeutic agent development process. Accelerated development and approval of experimental therapeutic agents have stimulated further interest in much earlier radiation-agent studies to increase the likelihood of success in phase III trials. To sustain this interest, more forward-thinking preclinical radiobiology experimental designs are needed to improve discovery of promising radiochemotherapy plus agent combinations for clinical trial testing. These experimental designs should better inform next-step radiation-agent clinical trial dose, schedule, exposure, and therapeutic effect. Recognizing the need for a better strategy to develop preclinical data supporting radiation-agent phase I or II trials, the National Cancer Institute (NCI)-Cancer Therapy Evaluation Program (CTEP) and the NCI-Molecular Radiation Therapeutics Branch of the Radiation Research Program have partnered to promote earlier radiobiology studies of CTEP portfolio agents. In this Seminars in Radiation Oncology article, four key components of this effort are discussed. First, we outline steps for accessing CTEP agents for preclinical testing. Second, we propose radiobiology studies that facilitate transition from preclinical testing to early phase trial activation. Third, we navigate steps that walk through CTEP agent strategic development paths available for radiation-agent testing. Fourth, we highlight a new NCI-sponsored cooperative agreement grant supporting in vitro and in vivo radiation-CTEP agent testing that informs early phase trial designs. Throughout the article, we include contemporary examples of successful radiation-agent development initiatives.
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Affiliation(s)
- Naoko Takebe
- Cancer Therapy Evaluation Program, National Cancer Institute, National Institutes of Health, Bethesda, MD.
| | - Mansoor M Ahmed
- Radiation Research Program, National Cancer Institute, Bethesda, MD
| | | | - Eric J Bernhard
- Radiation Research Program, National Cancer Institute, Bethesda, MD
| | - James Zwiebel
- Cancer Therapy Evaluation Program, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - C Norman Coleman
- Radiation Research Program, National Cancer Institute, Bethesda, MD
| | - Charles A Kunos
- Cancer Therapy Evaluation Program, National Cancer Institute, National Institutes of Health, Bethesda, MD
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Ratner ES, Zhu YL, Penketh PG, Berenblum J, Whicker ME, Huang PH, Lee Y, Ishiguro K, Zhu R, Sartorelli AC, Lin ZP. Triapine potentiates platinum-based combination therapy by disruption of homologous recombination repair. Br J Cancer 2016; 114:777-86. [PMID: 26964031 PMCID: PMC4984868 DOI: 10.1038/bjc.2016.54] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 02/06/2016] [Accepted: 02/12/2016] [Indexed: 12/24/2022] Open
Abstract
Background: Platinum resistance may be attributable to inherent or acquired proficiency in homologous recombination repair (HRR) in epithelial ovarian cancer (EOC). The objective of this study was to evaluate the efficacy of the small molecule inhibitor triapine to disrupt HRR and sensitise BRCA wild-type EOC cells to platinum-based combination therapy in vitro and in vivo. Methods: The sensitivity of BRCA wild-type cancer cells to olaparib, cisplatin, carboplatin, doxorubicin, or etoposide in combination with triapine was evaluated by clonogenic survival assays. The effects of triapine on HRR activity in cells were measured with a DR-GFP reporter assay. The ability of triapine to enhance the effects of the carboplatin-doxil combination on EOC tumour growth delay was determined using a xenograft tumour mouse model. Results: Platinum resistance is associated with wild-type BRCA status. Triapine inhibits HRR activity and enhances the sensitivity of BRCA wild-type cancer cells to cisplatin, olaparib, and doxorubicin. However, sequential combination of triapine and cisplatin is necessary to achieve synergism. Moreover, triapine potentiates platinum-based combination therapy against BRCA wild-type EOC cells and produces significant delay of EOC tumour growth. Conclusions: Triapine promises to augment the clinical efficacy of platinum-based combination regimens for treatment of platinum-resistant EOC with wild-type BRCA and proficient HRR activity.
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Affiliation(s)
- Elena S Ratner
- Department of Obstetrics, Gynecology & Reproductive Sciences, 333 Cedar Street, PO Box 208063, New Haven, CT 06520-8063, USA
| | - Yong-Lian Zhu
- Department of Obstetrics, Gynecology & Reproductive Sciences, 333 Cedar Street, PO Box 208063, New Haven, CT 06520-8063, USA
| | - Philip G Penketh
- Department of Obstetrics, Gynecology & Reproductive Sciences, 333 Cedar Street, PO Box 208063, New Haven, CT 06520-8063, USA
| | - Julie Berenblum
- Department of Obstetrics, Gynecology & Reproductive Sciences, 333 Cedar Street, PO Box 208063, New Haven, CT 06520-8063, USA
| | - Margaret E Whicker
- Department of Obstetrics, Gynecology & Reproductive Sciences, 333 Cedar Street, PO Box 208063, New Haven, CT 06520-8063, USA
| | | | - Yashang Lee
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA
| | - Kimiko Ishiguro
- Department of Obstetrics, Gynecology & Reproductive Sciences, 333 Cedar Street, PO Box 208063, New Haven, CT 06520-8063, USA
| | - Rui Zhu
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Alan C Sartorelli
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Z Ping Lin
- Department of Obstetrics, Gynecology & Reproductive Sciences, 333 Cedar Street, PO Box 208063, New Haven, CT 06520-8063, USA
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Lee EK, Kim CW, Kawanami H, Kishimura A, Niidome T, Mori T, Katayama Y. Utilization of a PNA-peptide conjugate to induce a cancer protease-responsive RNAi effect. RSC Adv 2015. [DOI: 10.1039/c5ra17737e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We designed a new siRNA system which turns on RNAi responding to a cancer cell-specific protease by using a peptide nucleic acid (PNA)-peptide conjugate.
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Affiliation(s)
- Eun Kyung Lee
- Graduate School of Systems Life Sciences
- Kyushu University
- Fukuoka
- Japan
| | - Chan Woo Kim
- Department of Applied Chemistry
- Faculty of Engineering
- Kyushu University
- Fukuoka
- Japan
| | - Hiroyuki Kawanami
- Graduate School of Systems Life Sciences
- Kyushu University
- Fukuoka
- Japan
| | - Akihiro Kishimura
- Graduate School of Systems Life Sciences
- Kyushu University
- Fukuoka
- Japan
- Department of Applied Chemistry
| | - Takuro Niidome
- Department of Applied Chemistry
- Faculty of Engineering
- Kyushu University
- Fukuoka
- Japan
| | - Takeshi Mori
- Graduate School of Systems Life Sciences
- Kyushu University
- Fukuoka
- Japan
- Department of Applied Chemistry
| | - Yoshiki Katayama
- Graduate School of Systems Life Sciences
- Kyushu University
- Fukuoka
- Japan
- Department of Applied Chemistry
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25
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Aye Y, Li M, Long MJC, Weiss RS. Ribonucleotide reductase and cancer: biological mechanisms and targeted therapies. Oncogene 2014; 34:2011-21. [PMID: 24909171 DOI: 10.1038/onc.2014.155] [Citation(s) in RCA: 276] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 04/25/2014] [Accepted: 04/26/2014] [Indexed: 12/16/2022]
Abstract
Accurate DNA replication and repair is essential for proper development, growth and tumor-free survival in all multicellular organisms. A key requirement for the maintenance of genomic integrity is the availability of adequate and balanced pools of deoxyribonucleoside triphosphates (dNTPs), the building blocks of DNA. Notably, dNTP pool alterations lead to genomic instability and have been linked to multiple human diseases, including mitochondrial disorders, susceptibility to viral infection and cancer. In this review, we discuss how a key regulator of dNTP biosynthesis in mammals, the enzyme ribonucleotide reductase (RNR), impacts cancer susceptibility and serves as a target for anti-cancer therapies. Because RNR-regulated dNTP production can influence DNA replication fidelity while also supporting genome-protecting DNA repair, RNR has complex and stage-specific roles in carcinogenesis. Nevertheless, cancer cells are dependent on RNR for de novo dNTP biosynthesis. Therefore, elevated RNR expression is a characteristic of many cancers, and an array of mechanistically distinct RNR inhibitors serve as effective agents for cancer treatment. The dNTP metabolism machinery, including RNR, has been exploited for therapeutic benefit for decades and remains an important target for cancer drug development.
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Affiliation(s)
- Y Aye
- 1] Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA [2] Department of Biochemistry, Weill Cornell Medical College, New York, NY, USA
| | - M Li
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
| | - M J C Long
- Graduate Program in Biochemistry, Brandeis University, Waltham, MA, USA
| | - R S Weiss
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
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Nishimoto K, Harris RBS, Rainey WE, Seki T. Sodium deficiency regulates rat adrenal zona glomerulosa gene expression. Endocrinology 2014; 155:1363-72. [PMID: 24422541 PMCID: PMC3959598 DOI: 10.1210/en.2013-1999] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Aldosterone is the primary adrenocortical hormone regulating sodium retention, and its production is under the control of the renin-angiotensin-aldosterone system (RAAS). In vitro, angiotensin II can induce aldosterone production in adrenocortical cells without causing cell proliferation. In vivo, a low-sodium diet activates the RAAS and aldosterone production, at least in part, through an expansion of the adrenal zona glomerulosa (zG) layer. Although these mechanisms have been investigated, RAAS effects on zG gene expression have not been fully elucidated. In this study, we took an unbiased approach to define the complete list of zG transcripts involved in RAAS activation. Adrenal glands were collected from 11-week old Sprague-Dawley rats fed either sodium-deficient (SDef), normal sodium (NS), or high-sodium (HS) diet for 72 hours, and laser-captured zG RNA was analyzed on microarrays containing 27 342 probe sets. When the SDef transcriptome was compared with NS transcriptome (SDef/NS comparison), only 79 and 10 probe sets were found to be up- and down-regulated more than two-fold in SDef, respectively. In SDef/HS comparison, 201 and 68 probe sets were up- and down-regulated in SDef, respectively. Upon gene ontology (GO) analysis of these gene sets, we identified three groups of functionally related GO terms: cell proliferation-associated (group 1), response to stimulus-associated (group 2), and cholesterol/steroid metabolism-associated (group 3) GO terms. Although genes in group 1 may play a critical role in zG layer expansion, those in groups 2 and 3 may have important functions in aldosterone production, and further investigations on these genes are warranted.
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Affiliation(s)
- Koshiro Nishimoto
- Department of Molecular and Integrative Physiology (K.N., W.E.R.), University of Michigan, Ann Arbor, Michigan 48109; Department of Physiology (R.B.S.H., T.S.), Georgia Regents University, Augusta, Georgia 30912; and Department of Urology (K.N.), Tachikawa Hospital, Tachikawa, 190-0022 Tokyo, Japan
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Lin ZP, Ratner ES, Whicker ME, Lee Y, Sartorelli AC. Triapine disrupts CtIP-mediated homologous recombination repair and sensitizes ovarian cancer cells to PARP and topoisomerase inhibitors. Mol Cancer Res 2014; 12:381-393. [PMID: 24413181 DOI: 10.1158/1541-7786.mcr-13-0480] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
UNLABELLED PARP inhibitors exploit synthetic lethality to target epithelial ovarian cancer (EOC) with hereditary BRCA mutations and defects in homologous recombination repair (HRR). However, such an approach is limited to a small subset of EOC patients and compromised by restored HRR due to secondary mutations in BRCA genes. Here, it was demonstrated that triapine, a small-molecule inhibitor of ribonucleotide reductase, enhances the sensitivity of BRCA wild-type EOC cells to the PARP inhibitor olaparib and the topoisomerase II inhibitor etoposide. Triapine abolishes olaparib-induced BRCA1 and Rad51 foci, and disrupts the BRCA1 interaction with the Mre11-Rad50-Nbs1 (MRN) complex in BRCA1 wild-type EOC cells. It has been shown that phosphorylation of CtIP (RBBP8) is required for the interaction with BRCA1 and with MRN to promote DNA double-strand break (DSB) resection during S and G(2) phases of the cell cycle. Mechanistic studies within reveal that triapine inhibits cyclin-dependent kinase (CDK) activity and blocks olaparib-induced CtIP phosphorylation through Chk1 activation. Furthermore, triapine abrogates etoposide-induced CtIP phosphorylation and DSB resection as evidenced by marked attenuation of RPA32 phosphorylation. Concurrently, triapine obliterates etoposide-induced BRCA1 foci and sensitizes BRCA1 wild-type EOC cells to etoposide. Using a GFP-based HRR assay, it was determined that triapine suppresses HRR activity induced by an I-SceI-generated DSB. These results suggest that triapine augments the sensitivity of BRCA wild-type EOC cells to drug-induced DSBs by disrupting CtIP-mediated HRR. IMPLICATIONS These findings provide a strong rationale for combining triapine with PARP or topoisomerase inhibitors to target HRR-proficient EOC cells.
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Affiliation(s)
- Z Ping Lin
- Department of Pharmacology, Yale Cancer Center,Yale University School of Medicine, New Haven, Connecticut
| | - Elena S Ratner
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, Yale Cancer Center,Yale University School of Medicine, New Haven, Connecticut
| | - Margaret E Whicker
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, Yale Cancer Center,Yale University School of Medicine, New Haven, Connecticut
| | - Yashang Lee
- Department of Internal Medicine, Section of Nephrology, Yale Cancer Center,Yale University School of Medicine, New Haven, Connecticut
| | - Alan C Sartorelli
- Department of Pharmacology, Yale Cancer Center,Yale University School of Medicine, New Haven, Connecticut
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Aird KM, Li H, Xin F, Konstantinopoulos PA, Zhang R. Identification of ribonucleotide reductase M2 as a potential target for pro-senescence therapy in epithelial ovarian cancer. Cell Cycle 2013; 13:199-207. [PMID: 24200970 DOI: 10.4161/cc.26953] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Epithelial ovarian cancer (EOC) is the leading cause of gynecological-related cancer deaths in the United States. There is, therefore, an urgent need to develop novel therapeutic strategies for this devastating disease. Cellular senescence is a state of stable cell growth arrest that acts as an important tumor suppression mechanism. Ribonucleotide reductase M2 (RRM2) plays a key role in regulating the senescence-associated cell growth arrest by controlling biogenesis of 2'-deoxyribonucleoside 5'-triphosphates (dNTPs). The role of RRM2 in EOC remains poorly understood. Here we show that RRM2 is expressed at higher levels in EOCs compared with either normal ovarian surface epithelium (P<0.001) or fallopian tube epithelium (P<0.001). RRM2 expression significantly correlates with the expression of Ki67, a marker of cell proliferation (P<0.001). Moreover, RRM2 expression positively correlates with tumor grade and stage, and high RRM2 expression independently predicts a shorter overall survival in EOC patients (P<0.001). To delineate the functional role of RRM2 in EOC, we knocked down RRM2 expression in a panel of EOC cell lines. Knockdown of RRM2 expression inhibits the growth of human EOC cells. Mechanistically, RRM2 knockdown triggers cellular senescence in these cells. Notably, this correlates with the induction of the DNA damage response, a known mediator of cellular senescence. These data suggest that targeting RRM2 in EOCs by suppressing its activity is a novel pro-senescence therapeutic strategy that has the potential to improve survival of EOC patients.
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Affiliation(s)
- Katherine M Aird
- Gene Expression and Regulation Program; The Wistar Institute Cancer Center; The Wistar Institute; Philadelphia, PA USA
| | - Hua Li
- Gene Expression and Regulation Program; The Wistar Institute Cancer Center; The Wistar Institute; Philadelphia, PA USA
| | - Frances Xin
- Cell and Molecular Biology Graduate Program; School of Medicine; The University of Pennsylvania; Philadelphia, PA USA
| | - Panagiotis A Konstantinopoulos
- Medical Gynecological Oncology Program; Dana Farber Cancer Institute; Harvard Medical School; Harvard University; Boston, MA USA
| | - Rugang Zhang
- Gene Expression and Regulation Program; The Wistar Institute Cancer Center; The Wistar Institute; Philadelphia, PA USA
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Shao J, Liu X, Zhu L, Yen Y. Targeting ribonucleotide reductase for cancer therapy. Expert Opin Ther Targets 2013; 17:1423-37. [PMID: 24083455 DOI: 10.1517/14728222.2013.840293] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Ribonucleotide reductase (RR) is a unique enzyme, because it is responsible for reducing ribonucleotides to their corresponding deoxyribonucleotides, which are the building blocks required for DNA replication and repair. Dysregulated RR activity is associated with genomic instability, malignant transformation and cancer development. The use of RR inhibitors, either as a single agent or combined with other therapies, has proven to be a promising approach for treating solid tumors and hematological malignancies. AREAS COVERED This review covers recent publications in the area of RR, which include: i) the structure, function and regulation of RR; ii) the roles of RR in cancer development; iii) the classification, mechanisms and clinical application of RR inhibitors for cancer therapy and iv) strategies for developing novel RR inhibitors in the future. EXPERT OPINION Exploring the possible nonenzymatic roles of RR subunit proteins in carcinogenesis may lead to new rationales for developing novel anticancer drugs. Updated information about the structure and holoenzyme models of RR will help in identifying potential sites in the protein that could be targets for novel RR inhibitors. Determining RR activity and subunit levels in clinical samples will provide a rational platform for developing personalized cancer therapies that use RR inhibitors.
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Affiliation(s)
- Jimin Shao
- Zhejiang University, School of Medicine, Department of Pathology and Pathophysiology , Hangzhou 310058 , China
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Rahman MA, Amin AR, Wang D, Koenig L, Nannapaneni S, Chen Z, Wang Z, Sica G, Deng X, Chen Z(G, Shin DM. RRM2 regulates Bcl-2 in head and neck and lung cancers: a potential target for cancer therapy. Clin Cancer Res 2013; 19:3416-28. [PMID: 23719266 PMCID: PMC3747783 DOI: 10.1158/1078-0432.ccr-13-0073] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Ribonucleotide reductase subunit M2 (RRM2) plays an active role in tumor progression. Recently, we reported that depletion of RRM2 by systemic delivery of a nanoparticle carrying RRM2-specific siRNA suppresses head and neck tumor growth. The aim of this study is to clarify the underlying mechanism by which RRM2 depletion inhibits tumor growth. EXPERIMENTAL DESIGN siRNA-mediated gene silencing was carried out to downregulate RRM2. Immunoblotting, reverse-transcriptase PCR, confocal microscopy, tissue fractionation, gene overexpression and knockdown were employed to analyze critical apoptosis signaling. Conventional immunohistochemistry and quantum dot-based immunofluorescence were applied to detect RRM2 and Bcl2 expression and localization in tissue samples from patients and mice. RESULTS Knockdown of RRM2 led to apoptosis through the intrinsic pathway in head and neck squamous cell carcinoma (HNSCC) and non-small cell lung cancer (NSCLC) cell lines. We showed that Bcl-2 is a key determinant controlling apoptosis, both in vitro and in vivo, and that RRM2 depletion significantly reduces Bcl-2 protein expression. We observed that RRM2 regulates Bcl-2 protein stability, with RRM2 suppression leading to increased Bcl-2 degradation, and identified their colocalization in HNSCC and NSCLC cells. In a total of 50 specimens each from patients with HNSCC and NSCLC, we identified the colocalization of Bcl-2 and RRM2 and found a significant positive correlation between their expression in HNSCC (R = 0.98; P < 0.0001) and NSCLC (R = 0.92; P < 0.0001) tumor tissues. CONCLUSIONS Our novel findings add to the knowledge of RRM2 in regulating expression of the antiapoptotic protein Bcl-2 and reveal a critical link between RRM2 and Bcl-2 in apoptosis signaling.
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Affiliation(s)
- Mohammad Aminur Rahman
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - A.R.M. Ruhul Amin
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Dongsheng Wang
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Lydia Koenig
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Sreenivas Nannapaneni
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Zhengjia Chen
- Department of Biostatistics and Bioinformatics, Emory University, Atlanta, GA, USA
| | - Zhibo Wang
- Department of Biostatistics and Bioinformatics, Emory University, Atlanta, GA, USA
| | - Gabriel Sica
- Department of Pathology, Emory University, Atlanta, GA, USA
| | - Xingming Deng
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - Zhuo (Georgia) Chen
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Dong M. Shin
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA, USA
- Corresponding Author: Dong M. Shin, Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, GA 30322. Phone: 1-404-778-2980, Fax: 1-404-778-5520.
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Wennier ST, Liu J, McFadden G. Bugs and drugs: oncolytic virotherapy in combination with chemotherapy. Curr Pharm Biotechnol 2013; 13:1817-33. [PMID: 21740354 DOI: 10.2174/138920112800958850] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 09/18/2010] [Indexed: 12/16/2022]
Abstract
Single agent therapies are rarely successful in treating cancer, particularly at metastatic or end stages, and survival rates with monotherapies alone are generally poor. The combination of multiple therapies to treat cancer has already driven significant improvements in the standard of care treatments for many types of cancers. The first combination treatments exploited for cancer therapy involved the use of several cytotoxic chemotherapy agents. Later, with the development of more targeted agents, the use of novel, less toxic drugs, in combination with the more classic cytotoxic drugs has proven advantageous for certain cancer types. Recently, the combination of oncolytic virotherapy with chemotherapy has shown that the use of these two therapies with very distinct anti-tumor mechanisms may also lead to synergistic interactions that ultimately result in increased therapeutic effects not achievable by either therapy alone. The mechanisms of synergy between oncolytic viruses (OVs) and chemotherapeutic agents are just starting to be elucidated. It is evident, however, that the success of these OV-drug combinations depends greatly on the particular OV, the drug(s) selected, and the cancer type targeted. This review summarizes the different OV-drug combinations investigated to date, including the use of second generation armed OVs, which have been studied with the specific purpose of generating synergistic interactions with particular chemotherapy agents. The known mechanisms of synergy between these OV-drug combinations are also summarized. The importance of further investigating these mechanisms of synergy will be critical in order to maximize the therapeutic efficacy of OV-drug combination therapies in the future.
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Affiliation(s)
- Sonia Tusell Wennier
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, P.O. Box 100266 Gainesville, FL 32610, USA
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D'Angiolella V, Esencay M, Pagano M. A cyclin without cyclin-dependent kinases: cyclin F controls genome stability through ubiquitin-mediated proteolysis. Trends Cell Biol 2012. [PMID: 23182110 DOI: 10.1016/j.tcb.2012.10.011] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cell cycle transitions are driven by the periodic oscillations of cyclins, which bind and activate cyclin-dependent kinases (CDKs) to phosphorylate target substrates. Cyclin F uses a substrate recruitment strategy similar to that of the other cyclins, but its associated catalytic activity is substantially different. Indeed, cyclin F is the founding member of the F-box family of proteins, which are the substrate recognition subunits of Skp1-Cul1-F-box protein (SCF) ubiquitin ligase complexes. Here, we discuss cyclin F function and recently identified substrates of SCF(cyclin)(F) involved in deoxyribonucleotide triphosphate (dNTP) production, centrosome duplication, and spindle formation. We highlight the relevance of cyclin F in controlling genome stability through ubiquitin-mediated proteolysis and the implications for cancer development.
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Affiliation(s)
- Vincenzo D'Angiolella
- Department of Pathology, NYU Cancer Institute, New York University School of Medicine, New York, NY 10016, USA. vincenzo.d'
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Kang MY, Kim HB, Piao C, Lee KH, Hyun JW, Chang IY, You HJ. The critical role of catalase in prooxidant and antioxidant function of p53. Cell Death Differ 2012; 20:117-29. [PMID: 22918438 DOI: 10.1038/cdd.2012.102] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The tumor suppressor p53 is an important regulator of intracellular reactive oxygen species (ROS) levels, although downstream mediators of p53 remain to be elucidated. Here, we show that p53 and its downstream targets, p53-inducible ribonucleotide reductase (p53R2) and p53-inducible gene 3 (PIG3), physically and functionally interact with catalase for efficient regulation of intracellular ROS, depending on stress intensity. Under physiological conditions, the antioxidant functions of p53 are mediated by p53R2, which maintains increased catalase activity and thereby protects against endogenous ROS. After genotoxic stress, high levels of p53 and PIG3 cooperate to inhibit catalase activity, leading to a shift in the oxidant/antioxidant balance toward an oxidative status, which could augment apoptotic cell death. These results highlight the essential role of catalase in p53-mediated ROS regulation and suggest that the p53/p53R2-catalase and p53/PIG3-catalase pathways are critically involved in intracellular ROS regulation under physiological conditions and during the response to DNA damage, respectively.
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Affiliation(s)
- M Y Kang
- DNA Damage Response Network Center, Chosun University School of Medicine, Gwangju, South Korea
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Cyclin F-mediated degradation of ribonucleotide reductase M2 controls genome integrity and DNA repair. Cell 2012; 149:1023-34. [PMID: 22632967 DOI: 10.1016/j.cell.2012.03.043] [Citation(s) in RCA: 280] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 02/01/2012] [Accepted: 03/24/2012] [Indexed: 11/20/2022]
Abstract
F-box proteins are the substrate binding subunits of SCF (Skp1-Cul1-F-box protein) ubiquitin ligase complexes. Using affinity purifications and mass spectrometry, we identified RRM2 (the ribonucleotide reductase family member 2) as an interactor of the F-box protein cyclin F. Ribonucleotide reductase (RNR) catalyzes the conversion of ribonucleotides to deoxyribonucleotides (dNTPs), which are necessary for both replicative and repair DNA synthesis. We found that, during G2, following CDK-mediated phosphorylation of Thr33, RRM2 is degraded via SCF(cyclin F) to maintain balanced dNTP pools and genome stability. After DNA damage, cyclin F is downregulated in an ATR-dependent manner to allow accumulation of RRM2. Defective elimination of cyclin F delays DNA repair and sensitizes cells to DNA damage, a phenotype that is reverted by expressing a nondegradable RRM2 mutant. In summary, we have identified a biochemical pathway that controls the abundance of dNTPs and ensures efficient DNA repair in response to genotoxic stress.
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Endogenous DNA replication stress results in expansion of dNTP pools and a mutator phenotype. EMBO J 2012; 31:895-907. [PMID: 22234187 DOI: 10.1038/emboj.2011.485] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Accepted: 12/09/2011] [Indexed: 11/09/2022] Open
Abstract
The integrity of the genome depends on diverse pathways that regulate DNA metabolism. Defects in these pathways result in genome instability, a hallmark of cancer. Deletion of ELG1 in budding yeast, when combined with hypomorphic alleles of PCNA results in spontaneous DNA damage during S phase that elicits upregulation of ribonucleotide reductase (RNR) activity. Increased RNR activity leads to a dramatic expansion of deoxyribonucleotide (dNTP) pools in G1 that allows cells to synthesize significant fractions of the genome in the presence of hydroxyurea in the subsequent S phase. Consistent with the recognized correlation between dNTP levels and spontaneous mutation, compromising ELG1 and PCNA results in a significant increase in mutation rates. Deletion of distinct genome stability genes RAD54, RAD55, and TSA1 also results in increased dNTP levels and mutagenesis, suggesting that this is a general phenomenon. Together, our data point to a vicious circle in which mutations in gatekeeper genes give rise to genomic instability during S phase, inducing expansion of the dNTP pool, which in turn results in high levels of spontaneous mutagenesis.
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36
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Lin ZP, Lee Y, Lin F, Belcourt MF, Li P, Cory JG, Glazer PM, Sartorelli AC. Reduced level of ribonucleotide reductase R2 subunits increases dependence on homologous recombination repair of cisplatin-induced DNA damage. Mol Pharmacol 2011; 80:1000-12. [PMID: 21875941 DOI: 10.1124/mol.111.074708] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ribonucleotide reductase (RNR) catalyzes the rate-limiting step in the production of deoxyribonucleoside triphosphates (dNTPs) required for replicative and repair DNA synthesis. Mammalian RNR is a heteromeric enzyme consisting primarily of R1 and R2 subunits during the S phase of the cell cycle. We have shown previously that the presence of excess R2 subunits protects p53-deficient human colon cancer cells from cisplatin-induced DNA damage and replication stress. However, the mode of DNA repair influenced by changes in the level of the R2 subunit remained to be defined. In the present study, we demonstrated that depletion of BRCA1, an important factor of homologous recombination repair (HRR), preferentially sensitized stable R2-knockdown p53(-/-) HCT116 cells to the cytotoxicity of cisplatin and γ-H2AX induction. In accord with this finding, these R2-knockdown cells exhibited increased dependence on HRR, as evidenced by elevated levels of cisplatin-induced Rad51 foci and sister chromatid exchange frequency. Furthermore, stable knockdown of the R2 subunit also led to decreased cisplatin-induced gap-filling synthesis in nucleotide excision repair (NER) and a reduced dATP level in the G(2)/M phase of the cell cycle. These results suggest that an increased level of the R2 subunit extends the availability of dATP in the G(2)/M phase to promote the repair of NER-mediated single-strand gaps that are otherwise converted into double-strand breaks in the subsequent S phase. We propose that HRR becomes important for recovery from cisplatin-DNA lesions when the postexcision process of NER is restrained by reduced levels of the R2 subunit and dATP in p53-deficient cancer cells.
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Affiliation(s)
- Z Ping Lin
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520-8066, USA.
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Shang H, Li Q, Feng G, Cui Z. Identification and characterization of alternative promoters, transcripts and protein isoforms of zebrafish R2 gene. PLoS One 2011; 6:e24089. [PMID: 21887375 PMCID: PMC3161108 DOI: 10.1371/journal.pone.0024089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 08/04/2011] [Indexed: 12/17/2022] Open
Abstract
Ribonucleotide reductase (RNR) is the rate-limiting enzyme in the de novo synthesis of deoxyribonucleoside triphosphates. Expression of RNR subunits is closely associated with DNA replication and repair. Mammalian RNR M2 subunit (R2) functions exclusively in DNA replication of normal cells due to its S phase-specific expression and late mitotic degradation. Herein, we demonstrate the control of R2 expression through alternative promoters, splicing and polyadenylation sites in zebrafish. Three functional R2 promoters were identified to generate six transcript variants with distinct 5′ termini. The proximal promoter contains a conserved E2F binding site and two CCAAT boxes, which are crucial for the transcription of R2 gene during cell cycle. Activity of the distal promoter can be induced by DNA damage to generate four transcript variants through alternative splicing. In addition, two novel splice variants were found to encode distinct N-truncated R2 isoforms containing residues for enzymatic activity but no KEN box essential for its proteolysis. These two N-truncated R2 isoforms remained in the cytoplasm and were able to interact with RNR M1 subunit (R1). Thus, our results suggest that multilayered mechanisms control the differential expression and function of zebrafish R2 gene during cell cycle and under genotoxic stress.
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Affiliation(s)
- Hanqiao Shang
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, People's Republic of China
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Abstract
The anticancer effects of thiosemicarbazones were once solely attributed to the inhibition of ribonucleotide reductase, an enzyme involved in the rate-limiting step of DNA synthesis. However, the mechanism behind this inhibition was initially not described. The ability of thiosemicarbazones to chelate metal ions has now been recognized as a major factor in their antiproliferative effects. This mini-review discusses current advances of an emerging 'new wave' of thiosemicarbazones as potent anticancer agents, describing recent insights into their mechanism of action. The redox activity of Fe-thiosemicarbazone complexes is critical in their anticancer activity, resulting in oxidative damage and the inhibition of ribonucleotide reductase. In vivo analysis indicates that some thiosemicarbazones show potential as chemotherapeutic agents.
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Pontarin G, Ferraro P, Rampazzo C, Kollberg G, Holme E, Reichard P, Bianchi V. Deoxyribonucleotide metabolism in cycling and resting human fibroblasts with a missense mutation in p53R2, a subunit of ribonucleotide reductase. J Biol Chem 2011; 286:11132-40. [PMID: 21297166 PMCID: PMC3064167 DOI: 10.1074/jbc.m110.202283] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Ribonucleotide reduction provides deoxynucleotides for nuclear and mitochondrial (mt) DNA replication and DNA repair. In cycling mammalian cells the reaction is catalyzed by two proteins, R1 and R2. A third protein, p53R2, with the same function as R2, occurs in minute amounts. In quiescent cells, p53R2 replaces the absent R2. In humans, genetic inactivation of p53R2 causes early death with mtDNA depletion, especially in muscle. We found that cycling fibroblasts from a patient with a lethal mutation in p53R2 contained a normal amount of mtDNA and showed normal growth, ribonucleotide reduction, and deoxynucleoside triphosphate (dNTP) pools. However, when made quiescent by prolonged serum starvation the mutant cells strongly down-regulated ribonucleotide reduction, decreased their dCTP and dGTP pools, and virtually abolished the catabolism of dCTP in substrate cycles. mtDNA was not affected. Also, nuclear DNA synthesis and the cell cycle-regulated enzymes R2 and thymidine kinase 1 decreased strongly, but the mutant cell populations retained unexpectedly larger amounts of the two enzymes than the controls. This difference was probably due to their slightly larger fraction of S phase cells and therefore not induced by the absence of p53R2 activity. We conclude that loss of p53R2 affects ribonucleotide reduction only in resting cells and leads to a decrease of dNTP catabolism by substrate cycles that counterweigh the loss of anabolic activity. We speculate that this compensatory mechanism suffices to maintain mtDNA in fibroblasts but not in muscle cells with a larger content of mtDNA necessary for their high energy requirements.
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siRNA knockdown of ribonucleotide reductase inhibits melanoma cell line proliferation alone or synergistically with temozolomide. J Invest Dermatol 2010; 131:453-60. [PMID: 20944646 DOI: 10.1038/jid.2010.310] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Systemically delivered small interfering RNA (siRNA) therapies for cancer have begun clinical development. The effects of siRNA-mediated knockdown of ribonucleotide reductase subunit-2 (RRM2), a rate-limiting enzyme in cell replication, were investigated in malignant melanoma, a cancer with a paucity of effective treatment options. A panel of human melanoma cell lines was transfected with siRNA to induce the knockdown of RRM2. Sequence-specific, siRNA-mediated inhibition of RRM2 effectively blocked cell proliferation and induced G1/S-phase cell cycle arrest. This effect was independent of the activating oncogenic mutations in the tested cell lines. Synergistic inhibition of melanoma cell proliferation was achieved using the combination of siRNA targeting RRM2 and temozolomide, an analog of the current standard of care for melanoma chemotherapy. In conclusion, siRNA-mediated RRM2 knockdown significantly inhibits proliferation of melanoma cell lines with different oncogenic mutations with synergistic enhancement in combination with temozolomide.
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41
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Morikawa T, Hino R, Uozaki H, Maeda D, Ushiku T, Shinozaki A, Sakatani T, Fukayama M. Expression of ribonucleotide reductase M2 subunit in gastric cancer and effects of RRM2 inhibition in vitro. Hum Pathol 2010; 41:1742-8. [PMID: 20825972 DOI: 10.1016/j.humpath.2010.06.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 05/31/2010] [Accepted: 06/03/2010] [Indexed: 12/12/2022]
Abstract
Ribonucleotide reductase M2 subunit is one of two subunits that constitute ribonucleotide reductase, the enzyme that catalyzes the conversion of ribonucleotide 5'-diphosphates into 2'-deoxyribonucleotides, which are required for DNA synthesis. This study was conducted to investigate the roles of ribonucleotide reductase M2 subunit in gastric cancer. The expression of ribonucleotide reductase M2 subunit protein was examined by immunohistochemistry. In normal gastric mucosa, ribonucleotide reductase M2 subunit expression was restricted to the neck regions of gastric pits and no expression was observed in the surface epithelium. Among 112 gastric cancer tissues, ribonucleotide reductase M2 subunit overexpression (≥10% cancer cells stained) was observed in 72 cases (64.3%). Ribonucleotide reductase M2 subunit overexpression was significantly associated with male sex (P = .015), presence of muscularis propria invasion (P = .020), presence of Epstein-Barr virus (P = .045), expression of survivin (P = .0014), and DNA methyltransferase 1 (P = .043), but not with age, histology, tumor size, lymph node metastasis or expression of phosphatase and tensin homolog, phosphorylated signal transducer, and activator of transcription 3 or p53. Suppression of ribonucleotide reductase M2 subunit synthesis, using small interfering RNA, inhibited the growth of 3 gastric cancer cell lines, MKN-1, MKN-7, and SNU-719. Our data suggest that ribonucleotide reductase M2 subunit overexpression could be associated with the gastric cancer progression and that suppression of its function is a potential therapeutic strategy in gastric cancer.
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Affiliation(s)
- Teppei Morikawa
- Department of Pathology, Graduate School of Medicine, the University of Tokyo, Tokyo, Japan
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42
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Chen YL, Eriksson S, Chang ZF. Regulation and functional contribution of thymidine kinase 1 in repair of DNA damage. J Biol Chem 2010; 285:27327-27335. [PMID: 20554529 DOI: 10.1074/jbc.m110.137042] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cellular supply of dNTPs is essential in the DNA replication and repair processes. Here we investigated the regulation of thymidine kinase 1 (TK1) in response to DNA damage and found that genotoxic insults in tumor cells cause up-regulation and nuclear localization of TK1. During recovery from DNA damage, TK1 accumulates in p53-null cells due to a lack of mitotic proteolysis as these cells are arrested in the G(2) phase by checkpoint activation. We show that in p53-proficient cells, p21 expression in response to DNA damage prohibits G(1)/S progression, resulting in a smaller G(2) fraction and less TK1 accumulation. Thus, the p53 status of tumor cells affects the level of TK1 after DNA damage through differential cell cycle control. Furthermore, it was shown that in HCT-116 p53(-/-) cells, TK1 is dispensable for cell proliferation but crucial for dTTP supply during recovery from DNA damage, leading to better survival. Depletion of TK1 decreases the efficiency of DNA repair during recovery from DNA damage and generates more cell death. Altogether, our data suggest that more dTTP synthesis via TK1 take place after genotoxic insults in tumor cells, improving DNA repair during G(2) arrest.
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Affiliation(s)
- Yen-Ling Chen
- Graduate Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei 100, Taiwan
| | - Staffan Eriksson
- Department of Anatomy, Physiology and Biochemistry, The Swedish University of Agricultural Sciences, Biomedical Center, S-751 23 Uppsala, Sweden
| | - Zee-Fen Chang
- Graduate Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei 100, Taiwan; Institute of Biochemistry and Molecular Biology, National Yang-Ming University, No. 155, Section 2, Linong Street, Taipei 112, Taiwan.
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Kunos CA, Chiu SM, Pink J, Kinsella TJ. Modulating radiation resistance by inhibiting ribonucleotide reductase in cancers with virally or mutationally silenced p53 protein. Radiat Res 2009; 172:666-76. [PMID: 19929413 DOI: 10.1667/rr1858.1] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Therapeutic ionizing radiation damages DNA, increasing p53-regulated ribonucleotide reductase (RNR) activity required for de novo synthesis of the deoxyribonucleotide triphosphates used during DNA repair. This study investigated the pharmacological inhibition of RNR in cells of virally or mutationally silenced p53 cancer cell lines using 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, Triapine(R), NSC #663249), a chemotherapeutic radiosensitizer that equally inhibits RNR M2 and p53R2 small subunits. The effects of 3-AP on RNR inhibition and resulting radiosensitization were evaluated in cervical (CaSki, HeLa and C33-a) and colon (RKO, RKO-E6) cancer cells. 3-AP treatment significantly enhanced radiation-related cytotoxicity in cervical and colon cancer cells. 3-AP treatment significantly decreased RNR activity, caused prolonged radiation-induced DNA damage, and resulted in an extended G(1)/S-phase cell cycle arrest in all cell lines. Similar effects were observed in both RKO and RKO-E6 cells, suggesting a p53-independent mechanism of radiosensitization. We conclude that inhibition of ribonucleotide reductase by 3-AP enhances radiation-mediated cytotoxicity independent of p53 regulation by impairing repair processes that rely on deoxyribonucleotide production, thereby substantially increasing the radiation sensitivity of human cancers.
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Affiliation(s)
- Charles A Kunos
- Departments of Radiation Oncology, Case Comprehensive Cancer Center, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, 11100 Euclid Avenue, Cleveland, Ohio 44106, USA.
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44
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Chimploy K, Díaz GD, Li Q, Carter O, Dashwood WM, Mathews CK, Williams DE, Bailey GS, Dashwood RH. E2F4 and ribonucleotide reductase mediate S-phase arrest in colon cancer cells treated with chlorophyllin. Int J Cancer 2009; 125:2086-94. [PMID: 19585502 DOI: 10.1002/ijc.24559] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Chlorophyllin (CHL) is a water-soluble derivative of chlorophyll that exhibits cancer chemopreventive properties, but which also has been studied for its possible cancer therapeutic effects. We report here that human colon cancer cells treated with CHL accumulate in S-phase of the cell cycle, and this is associated with reduced expression levels of p53, p21, and other G(1)/S checkpoint controls. At the same time, E2F1 and E2F4 transcription factors become elevated and exhibit increased DNA binding activity. In CHL-treated colon cancer cells, bromodeoxyuridine pulse-chase experiments provided evidence for the inhibition of DNA synthesis. Ribonucleotide reductase (RR), a pivotal enzyme for DNA synthesis and repair, was reduced at the mRNA and protein level after CHL treatment, and the enzymatic activity was inhibited in a concentration-dependent manner both in vitro and in vivo. Immunoblotting revealed that expression levels of RR subunits R1, R2, and p53R2 were reduced by CHL treatment in HCT116 (p53(+/+)) and HCT116 (p53(-/-)) cells, supporting a p53-independent mechanism. Prior studies have shown that reduced levels of RR small subunits can increase the sensitivity of colon cancer cells to clinically used DNA-damaging agents and RR inhibitors. We conclude that by inhibiting R1, R2, and p53R2, CHL has the potential to be effective in the clinical setting, when used alone or in combination with currently available cancer therapeutic agents.
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Affiliation(s)
- Korakod Chimploy
- Linus Pauling Institute, Oregon State University, Corvallis, OR 97331-6512, USA
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45
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Ferrandina G, Mey V, Nannizzi S, Ricciardi S, Petrillo M, Ferlini C, Danesi R, Scambia G, Del Tacca M. Expression of nucleoside transporters, deoxycitidine kinase, ribonucleotide reductase regulatory subunits, and gemcitabine catabolic enzymes in primary ovarian cancer. Cancer Chemother Pharmacol 2009; 65:679-86. [DOI: 10.1007/s00280-009-1073-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 07/07/2009] [Indexed: 12/12/2022]
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Inhibitory mechanisms of heterocyclic carboxaldehyde thiosemicabazones for two forms of human ribonucleotide reductase. Biochem Pharmacol 2009; 78:1178-85. [PMID: 19576866 DOI: 10.1016/j.bcp.2009.06.103] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 06/23/2009] [Accepted: 06/24/2009] [Indexed: 11/20/2022]
Abstract
Two forms of ribonucleotide reductase (RR), consisting of M1 with M2 subunits and M1 with p53R2 subunits, are involved in DNA replication and damage repair, respectively. 3-Aminopyridine-2-carboxaldehyde thiosemicarbazone (3AP), one of the heterocyclic carboxaldehyde thiosemicabazones (HCTs), is a potent RR inhibitor in clinical trial for cancer treatment. In this study, 3AP and its 7 derivatives showed 100-1000-fold higher inhibitory potency on KB nasopharyngeal carcinoma cells than hydroxyurea and were fully active against hydroxyurea- and gemcitabine-resistant KB cells. In vitro RR assays using two recombinant RRs showed that all 8 HCTs decreased the activity of both RRs in a dose-dependent manner and the efficiency was compatible with that on cell proliferation inhibition. Iron has different impact on the behavior of the compounds toward RRs. In the absence of iron, the HCTs showed more selective inhibition for p53R2-M1 than M2-M1, while addition of iron increased their activity but reduced their selectivity for two RRs. Radioligand binding assays showed that [(3)H]3AP directly bounded to the small subunits. Electron paramagnetic resonance measurements demonstrated that these HCTs generated reactive oxygen species with ferrous iron, which quenched the diiron-tyrosyl radical co-factor of the small subunits and hence the enzyme activity. While the ROS may be a common mediator responsible for the potent activity of the HCTs, the different characteristics of the small subunit proteins are probably associated with the subunit-selectivity of inhibition. Better understanding of the mechanism of action of RR inhibition may improve design of new potent and subunit-selective RR inhibitors for cancer therapy.
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Zhang YW, Jones TL, Martin SE, Caplen NJ, Pommier Y. Implication of checkpoint kinase-dependent up-regulation of ribonucleotide reductase R2 in DNA damage response. J Biol Chem 2009; 284:18085-95. [PMID: 19416980 DOI: 10.1074/jbc.m109.003020] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
To investigate drug mechanisms of action and identify molecular targets for the development of rational drug combinations, we conducted synthetic small interfering RNA (siRNA)-based RNAi screens to identify genes whose silencing affects anti-cancer drug responses. Silencing of RRM1 and RRM2, which encode the large and small subunits of the human ribonucleotide reductase complex, respectively, markedly enhanced the cytotoxicity of the topoisomerase I inhibitor camptothecin (CPT). Silencing of RRM2 was also found to enhance DNA damage as measured by histone gamma-H2AX. Further studies showed that CPT up-regulates both RRM1 and RRM2 mRNA and protein levels and induces the nuclear translocation of RRM2. The checkpoint kinase 1 (Chk1) was up-regulated and activated in response to CPT, and CHEK1 down-regulation by siRNA and small molecule inhibitors of Chk1 blocked RRM2 induction by CPT. CHEK1 siRNA also suppressed E2F1 up-regulation by CPT, and silencing of E2F1 suppressed the up-regulation of RRM2. Silencing of ATR or ATM and inhibition of ATM activity by KU-55933 blocked Chk1 activation and RRM2 up-regulation. This study links the known components of CPT-induced DNA damage response with proteins required for the synthesis of dNTPs and DNA repair. Specifically, we propose that upon DNA damage, Chk1 activation, mediated by ATM and ATR, up-regulates RRM2 expression through the E2F1 transcription factor. Up-regulation in RRM2 expression levels coupled with its nuclear recruitment suggests an active role for ribonucleotide reductase in the cellular response to CPT-mediated DNA damage that could potentially be exploited as a strategy for enhancing the efficacy of topoisomerase I inhibitors.
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Affiliation(s)
- Yong-Wei Zhang
- Laboratory of Molecular Pharmacology, Genetics Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
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48
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Regulation of p53R2 and its role as potential target for cancer therapy. Cancer Lett 2009; 276:1-7. [DOI: 10.1016/j.canlet.2008.07.019] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Revised: 07/14/2008] [Accepted: 07/14/2008] [Indexed: 12/16/2022]
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49
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Lin SF, Gao SP, Price DL, Li S, Chou TC, Singh P, Huang YY, Fong Y, Wong RJ. Synergy of a herpes oncolytic virus and paclitaxel for anaplastic thyroid cancer. Clin Cancer Res 2008; 14:1519-28. [PMID: 18316577 DOI: 10.1158/1078-0432.ccr-07-4628] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Novel therapeutic regimens are needed to improve the dismal outcomes of patients with anaplastic thyroid cancer (ATC). Oncolytic herpes simplex virus have shown promising activity against human ATC. We studied the application of oncolytic herpes simplex virus (G207 and NV1023) in combination with currently used chemotherapeutic drugs (paclitaxel and doxorubicin) for the treatment of ATC. EXPERIMENTAL DESIGN AND RESULTS All four agents showed dose-response cytotoxicity in vitro for the human ATC cell lines KAT4 and DRO90-1. G207, combined with paclitaxel, showed synergistic cytotoxicity. Chou-Talalay combination indices ranged from 0.56 to 0.66 for KAT4, and 0.68 to 0.74 for DRO90-1 at higher affected fractions. Paclitaxel did not enhance G207 viral entry and early gene expression or G207 viral replication. Paclitaxel combined with G207 compared with single-agent treatment or controls showed significantly increased microtubule acetylation, mitotic arrest, aberrant chromatid separation, inhibition of metaphase to anaphase progression, and apoptosis. A single i.t. injection of G207 combined with biweekly i.p. paclitaxel injections in athymic nude mice bearing KAT4 flank tumors showed significantly reduced mean tumor volume (74 +/- 38 mm(3)) compared with G207 alone (388 +/- 109 mm(3)), paclitaxel alone (439 +/- 137 mm(3)), and control (520 +/- 160 mm(3)) groups at 16 days. There was no morbidity in vivo attributable to therapy. CONCLUSIONS Mechanisms of paclitaxel antitumoral activity, including microtubule acetylation, mitotic block, and apoptosis, were enhanced by G207, which also has direct oncolytic effects. Combination of G207 and paclitaxel therapy is synergistic in treating ATC and holds promise for patients with this fatal disease.
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Affiliation(s)
- Shu-Fu Lin
- Department of Surgery and Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
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50
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Liguori L, Marques B, Villegas-Mendez A, Rothe R, Lenormand JL. Liposomes-mediated delivery of pro-apoptotic therapeutic membrane proteins. J Control Release 2008; 126:217-27. [DOI: 10.1016/j.jconrel.2007.12.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Revised: 11/29/2007] [Accepted: 12/03/2007] [Indexed: 10/22/2022]
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