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Mizuguchi D, Yamamoto T, Omiya Y, Endo K, Tano K, Oya M, Takano S. Novel Screening Tool Using Non-linguistic Voice Features Derived from Simple Phrases to Detect Mild Cognitive Impairment and Dementia. JAR Life 2023; 12:72-76. [PMID: 37637273 PMCID: PMC10450207 DOI: 10.14283/jarlife.2023.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 07/13/2023] [Indexed: 08/29/2023]
Abstract
Appropriate intervention and care in detecting cognitive impairment early are essential to effectively prevent the progression of cognitive deterioration. Diagnostic voice analysis is a noninvasive and inexpensive screening method that could be useful for detecting cognitive deterioration at earlier stages such as mild cognitive impairment. We aimed to distinguish between patients with dementia or mild cognitive impairment and healthy controls by using purely acoustic features (i.e., nonlinguistic features) extracted from two simple phrases. Voice was analyzed on 195 recordings from 150 patients (age, 45-95 years). We applied a machine learning algorithm (LightGBM; Microsoft, Redmond, WA, USA) to test whether the healthy control, mild cognitive impairment, and dementia groups could be accurately classified, based on acoustic features. Our algorithm performed well: area under the curve was 0.81 and accuracy, 66.7% for the 3-class classification. Thus, our vocal biomarker is useful for automated assistance in diagnosing early cognitive deterioration.
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Affiliation(s)
| | | | | | - K Endo
- PST Inc., Yokohama, Japan
| | - K Tano
- Takeyama Hospital, Yokohama, Japan
| | - M Oya
- Takeyama Hospital, Yokohama, Japan
| | - S Takano
- Honjo Kodama Hospital, Honjo, Japan
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Nakano T, Moriwaki T, Tsuda M, Miyakawa M, Hanaichi Y, Sasanuma H, Hirota K, Kawanishi M, Ide H, Tano K, Bessho T. SPRTN and TDP1/TDP2 Independently Suppress 5-Aza-2'-deoxycytidine-Induced Genomic Instability in Human TK6 Cell Line. Chem Res Toxicol 2022; 35:2059-2067. [PMID: 36282523 DOI: 10.1021/acs.chemrestox.2c00213] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
DNA-protein cross-links (DPCs) are generated by internal factors such as cellular aldehydes that are generated during normal metabolism and external factors such as environmental mutagens. A nucleoside analog, 5-aza-2'-deoxycytidine (5-azadC), is randomly incorporated into the genome during DNA replication and binds DNA methyltransferase 1 (DNMT1) covalently to form DNMT1-DPCs without inducing DNA strand breaks. Despite the recent progress in understanding the mechanisms of DPCs repair, how DNMT1-DPCs are repaired is unclear. The metalloprotease SPRTN has been considered as the primary enzyme to degrade protein components of DPCs to initiate the repair of DPCs. In this study, we showed that SPRTN-deficient (SPRTN-/-) human TK6 cells displayed high sensitivity to 5-azadC, and the removal of 5-azadC-induced DNMT1-DPCs was significantly slower in SPRTN-/- cells than that in wild-type cells. We also showed that the ubiquitination-dependent proteasomal degradation, which was independent of the SPRTN-mediated processing, was also involved in the repair of DNMT1-DPCs. Unexpectedly, we found that cells that are double deficient in tyrosyl DNA phosphodiesterase 1 and 2 (TDP1-/-TDP2-/-) were also sensitive to 5-azadC, although the removal of 5-azadC-induced DNMT1-DPCs was not compromised significantly. Furthermore, the 5-azadC treatment induced a marked accumulation of chromosomal breaks in SPRTN-/- as well as TDP1-/-TDP2-/- cells compared to wild-type cells, strongly suggesting that the 5-azadC-induced cell death was attributed to chromosomal DNMT1-DPCs. We conclude that SPRTN protects cells from 5-azadC-induced DNMT1-DPCs, and SPRTN may play a direct proteolytic role against DNMT1-DPCs and TDP1/TDP2 also contributes to suppress genome instability caused by 5-azadC in TK6 cells.
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Affiliation(s)
- Toshiaki Nakano
- DNA Damage Chemistry Research Group, Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Kizugawa, Kyoto 619-0215, Japan
| | - Takahito Moriwaki
- Department of Molecular and Genetic Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Masataka Tsuda
- Program of Mathematical and Life Sciences, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Misa Miyakawa
- Environmental Molecular Toxicology, Department of Biological Chemistry Graduate School of Science, Osaka Metropolitan University, Sakai, Osaka 599-8570, Japan
| | - Yuto Hanaichi
- Environmental Molecular Toxicology, Department of Biological Chemistry Graduate School of Science, Osaka Metropolitan University, Sakai, Osaka 599-8570, Japan
| | - Hiroyuki Sasanuma
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506 Japan
| | - Kouji Hirota
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Tokyo 192-0397 Japan
| | - Masanobu Kawanishi
- Environmental Molecular Toxicology, Department of Biological Chemistry Graduate School of Science, Osaka Metropolitan University, Sakai, Osaka 599-8570, Japan
| | - Hiroshi Ide
- Program of Mathematical and Life Sciences, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Keizo Tano
- Environmental Molecular Toxicology, Department of Biological Chemistry Graduate School of Science, Osaka Metropolitan University, Sakai, Osaka 599-8570, Japan
| | - Tadayoshi Bessho
- The Eppley Institute for Research in Cancer and Allied Diseases, Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, 986805 Nebraska Medical Center, Omaha, Nebraska 68198-6805, United States
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Masunaga SI, Sanada Y, Tano K, Sakurai Y, Tanaka H, Takata T, Suzuki M, Ono K. An attempt to improve the therapeutic effect of boron neutron capture therapy using commonly employed 10B-carriers based on analytical studies on the correlation among quiescent tumor cell characteristics, tumor heterogeneity and cancer stemness. J Radiat Res 2020; 61:876-885. [PMID: 32601693 PMCID: PMC7674684 DOI: 10.1093/jrr/rraa048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/04/2020] [Indexed: 05/03/2023]
Abstract
Based on our previously published reports concerning the response of quiescent (Q) tumor cell populations to boron neutron capture therapy (BNCT), the heterogeneous microdistribution of 10B in tumors, which is influenced by the tumor microenvironment and the characteristics of the 10B delivery carriers, has been shown to limit the therapeutic effect of BNCT on local tumors. It was also clarified that the characteristics of 10B-carriers for BNCT and the type of combined treatment in BNCT can also affect the potential for distant lung metastases from treated local tumors. We reviewed the findings concerning the response of Q tumor cell populations to BNCT, mainly focusing on reports we have published so far, and we identified the mode of BNCT that currently offers the best therapeutic gain from the viewpoint of both controlling local tumor and suppressing the potential for distant lung metastasis. In addition, based on the finding that oxygenated Q tumor cells showed a large capacity to recover from DNA damage after cancer therapy, the interrelationship among the characteristics in Q tumor cell populations, tumor heterogeneity and cancer stemness was also discussed.
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Affiliation(s)
- Shin-ichiro Masunaga
- Particle Radiation Biology, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Japan
- Corresponding author. Particle Radiation Biology, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan. Tel: +81 72 451 2406; Fax: 81 72 451 2393;
| | - Yu Sanada
- Particle Radiation Biology, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Japan
| | - Keizo Tano
- Particle Radiation Biology, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Japan
| | - Yoshinori Sakurai
- Particle Radiation Medical Physics, Particle Radiation Research Center, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Japan
| | - Hiroki Tanaka
- Particle Radiation Medical Physics, Particle Radiation Research Center, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Japan
| | - Takushi Takata
- Particle Radiation Medical Physics, Particle Radiation Research Center, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Japan
| | - Minoru Suzuki
- Particle Radiation Oncology, Particle Radiation Research Center, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Japan
| | - Koji Ono
- Kansai BNCT Medical Center, Osaka Medical College, Japan
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Masunaga SI, Sakurai Y, Tanaka H, Takata T, Suzuki M, Sanada Y, Tano K, Maruhashi A, Ono K. Usefulness of combination with both continuous administration of hypoxic cytotoxin and mild temperature hyperthermia in boron neutron capture therapy in terms of local tumor response and lung metastatic potential. Int J Radiat Biol 2019; 95:1708-1717. [PMID: 31545117 DOI: 10.1080/09553002.2019.1666214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Purpose: To evaluate the usefulness of combined treatment with both continuous administration of a hypoxic cytotoxin, tirapazamine (TPZ) and mild temperature hyperthermia (MTH) in boron neutron capture therapy (BNCT) in terms of local tumor response and lung metastatic potential, referring to the response of intratumor quiescent (Q) cells.Materials and methods: B16-BL6 melanoma tumor-bearing C57BL/6 mice were continuously given 5-bromo-2'-deoxyuridine (BrdU) to label all proliferating (P) cells. The tumors received reactor thermal neutron beam irradiation following the administration of a 10B-carrier (L-para-boronophenylalanine-10B (BPA) or sodium mercaptoundecahydrododecaborate-10B (BSH)) after single intraperitoneal injection of an acute hypoxia-releasing agent (nicotinamide), MTH (40 °C for 60 min), and 24-h continuous subcutaneous infusion of TPZ or combined treatment with both TPZ and MTH. Immediately after irradiation, cells from some tumors were isolated and incubated with a cytokinesis blocker. The responses of the Q and total (=P + Q) tumor cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In other tumor-bearing mice, 17 days after irradiation, macroscopic lung metastases were enumerated.Results: BPA-BNCT increased the sensitivity of the total tumor cell population more than BSH-BNCT. However, the sensitivity of Q cells treated with BPA was lower than that of BSH-treated Q cells. With or without a 10B-carrier, combination with continuously administered TPZ with or without MTH enhanced the sensitivity of the both total and Q cells, especially Q cells. Even without irradiation, nicotinamide treatment decreased the number of lung metastases. With irradiation, BPA-BNCT, especially in combination with combined treatment with both TPZ and MTH as well as nicotinamide treatment, showed the potential to reduce the number more than BSH-BNCT.Conclusion: BSH-BNCT combined with TPZ with or without MTH improved local tumor control, while BPA-BNCT in combination with both TPZ and MTH as well as nicotinamide is thought to reduce the number of lung metastases. It was elucidated that control of the chronic hypoxia-rich Q cell population in the primary solid tumor has the potential to impact the control of local tumors as a whole and that control of the acute hypoxia-rich total tumor cell population in the primary solid tumor has the potential to impact the control of lung metastases.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Particle Radiation Biology, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Yoshinori Sakurai
- Radiation Medical Physics, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Hiroki Tanaka
- Radiation Medical Physics, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Takushi Takata
- Radiation Medical Physics, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Minoru Suzuki
- Particle Radiation Oncology Center, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Yu Sanada
- Particle Radiation Biology, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Keizo Tano
- Particle Radiation Biology, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Akira Maruhashi
- Radiation Medical Physics, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Koji Ono
- Kansai BNCT Medical Center, Osaka Medical College, Osaka, Japan
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Masunaga SI, Tano K, Sanada Y, Suzuki M, Takahashi A, Ohnishi K, Ono K. Effects of p53 Status of Tumor Cells and Combined Treatment With Mild Hyperthermia, Wortmannin or Caffeine on Recovery From Radiation-Induced Damage. World J Oncol 2019; 10:132-141. [PMID: 31312280 PMCID: PMC6615912 DOI: 10.14740/wjon1203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 06/08/2019] [Indexed: 11/11/2022] Open
Abstract
Background The aim of the study was to examine the dependency of p53 status and the usefulness of mild hyperthermia (MHT) as an inhibitor of recovery from radiation-induced damage, referring to the response of quiescent (Q) tumor cell population. Methods Human head and neck squamous cell carcinoma cells transfected with mutant TP53 (SAS/mp53) or with neo vector (SAS/neo) were injected subcutaneously into left hind legs of nude mice. Tumor-bearing mice received 5-bromo-2’-deoxyuridine (BrdU) continuously to label all intratumor proliferating (P) cells. They received high dose-rate γ-ray irradiation (HDR) immediately followed by localized MHT (40 °C for 2 h), or caffeine or wortmannin administration, or low dose-rate γ-ray irradiation simultaneously with localized MHT or caffeine or wortmannin administration. Nine hours after the start of irradiation, the tumor cells were isolated and incubated with a cytokinesis blocker, and the micronucleus (MN) frequency in cells without BrdU labeling (= Q cells) was determined using immunofluorescence staining for BrdU. Results SAS/neo tumor cells, especially intratumor Q cell populations, showed a marked reduction in sensitivity due to the recovery from radiation-induced damage, compared with the total or Q tumor cells within SAS/mp53 tumors that showed little recovery capacity. The recovery from radiation-induced damage was thought to be a p53-dependent event. In both total and Q tumor cells within SAS/neo tumors, especially the latter, MHT efficiently suppressed the reduction in sensitivity caused by leaving an interval between HDR irradiation and the assay and decreasing the irradiation dose-rate, as well as the combination with wortmannin administration. Conclusions From the viewpoint of solid tumor control as a whole, including intratumor Q-cell control, non-toxic MHT is useful for suppressing the recovery from radiation-induced damage, as well as wortmannin treatment combined with γ-ray irradiation.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Particle Radiation Biology, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Keizo Tano
- Particle Radiation Biology, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Yu Sanada
- Particle Radiation Biology, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Minoru Suzuki
- Particle Radiation Oncology, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Akihisa Takahashi
- Gunma University Heavy Ion Medical Center, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Ken Ohnishi
- Department of Biology, Center for Humanity and Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami, Inashiki-gun, Ibaraki 300-0394, Japan
| | - Koji Ono
- Kansai BNCT Medical Center, Osaka Medical College, 2-7 Daigaku-machi Takatsuki, Osaka 569-8686, Japan
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Musk GC, Kershaw H, Tano K, Niklasson A, von Unge M, Dilley RJ. Reactions to Gudair® vaccination identified in sheep used for biomedical research. Aust Vet J 2019; 97:56-60. [DOI: 10.1111/avj.12788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 10/26/2018] [Accepted: 01/15/2019] [Indexed: 12/29/2022]
Affiliation(s)
- GC Musk
- Animal Care Services; The University of Western Australia; M720, 35 Stirling Hwy, Crawley 6009 Western Australia Australia
| | - H Kershaw
- Animal Care Services; The University of Western Australia; M720, 35 Stirling Hwy, Crawley 6009 Western Australia Australia
| | - K Tano
- Department of Clinical Science, Otorhinolaryngology; Umeå University; Umeå Sweden
| | - A Niklasson
- Department of Clinical Science, Otorhinolaryngology; Umeå University; Umeå Sweden
| | - M von Unge
- Department of Clinical Medicine; Division of Surgery, University of Oslo; Oslo Norway
- Akershus University Hospital; Lorenskog Norway
| | - RJ Dilley
- Ear Sciences Centre; School of Medicine, the University of Western Australia; Crawley WA Australia
- Ear Science Institute Australia; Subiaco WA Australia
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Masunaga SI, Sakurai Y, Tanaka H, Takata T, Suzuki M, Sanada Y, Tano K, Maruhashi A, Ono K. Effect of a change in reactor power on response of murine solid tumors in vivo, referring to impact on quiescent tumor cell population. Int J Radiat Biol 2018; 95:635-645. [PMID: 30557082 DOI: 10.1080/09553002.2019.1558300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
PURPOSE To examine the effect of a change in reactor power on the response of solid tumors, referring to impact on quiescent (Q) tumor cell population. MATERIALS AND METHODS Tumor-bearing mice received 5-bromo-2'-deoxyuridine (BrdU) to label all proliferating (P) tumor cells, and were treated with boronophenylalanine-10B (BPA) or sodium mercaptododecaborate-10B (BSH). After reactor neutron beam irradiation at a power of 1 or 5 MW with an identical beam spectrum, cells from tumors were isolated and incubated with a cytokinesis blocker. The responses of BrdU-unlabeled Q and total (P + Q) tumor cells were assessed based on the frequencies of micronucleation using immunofluorescence staining for BrdU. RESULTS After neutron irradiation with or without 10B-carrier, radio-sensitivity was reduced by decreasing reactor power in both cells, especially in Q cells and after irradiation with BPA. The values of relative and compound biological effectiveness were larger at a power of 5 MW and in Q cells than at a power of 1 MW and in total cells, respectively. The sensitivity difference between total and Q cells was widened when combined with 10B-carrier, especially with BPA, and through decreasing reactor power. CONCLUSION 5 MW is more advantageous than 1 MW for boron neutron capture therapy.
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Affiliation(s)
- Shin-Ichiro Masunaga
- a Particle Radiation Biology, Division of Radiation Life Science , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
| | - Yoshinori Sakurai
- b Radiation Medical Physics, Division of Radiation Life Science , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
| | - Hiroki Tanaka
- b Radiation Medical Physics, Division of Radiation Life Science , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
| | - Takushi Takata
- b Radiation Medical Physics, Division of Radiation Life Science , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
| | - Minoru Suzuki
- c Particle Radiation Oncology Center , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
| | - Yu Sanada
- a Particle Radiation Biology, Division of Radiation Life Science , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
| | - Keizo Tano
- a Particle Radiation Biology, Division of Radiation Life Science , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
| | - Akira Maruhashi
- b Radiation Medical Physics, Division of Radiation Life Science , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
| | - Koji Ono
- c Particle Radiation Oncology Center , Institute for Integrated Radiation and Nuclear Science, Kyoto University , Sennan-gun , Osaka , Japan
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Masunaga SI, Kobayashi J, Tano K, Sanada Y, Suzuki M, Ono K. The Effect of p53 Status on Radio-Sensitivity of Quiescent Tumor Cell Population Irradiated With γ-Rays at Various Dose Rates. J Clin Med Res 2018; 10:815-821. [PMID: 30344816 PMCID: PMC6188028 DOI: 10.14740/jocmr3610w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 09/10/2018] [Indexed: 11/11/2022] Open
Abstract
Background The aim of the study was to clarify the effect of p53 status of tumor cells on radio-sensitivity of solid tumors following γ-ray irradiation at various dose rates, referring to the response of intratumor quiescent (Q) cells. Methods Human head and neck squamous cell carcinoma cells transfected with mutant TP53 (SAS/mp53) or with neo vector (SAS/neo) were injected subcutaneously into hind legs of nude mice. Tumor bearing mice received 5-bromo-2’-deoxyuridine (BrdU) continuously to label all intratumor proliferating (P) cells. They received γ-rays at a high, middle or low dose rate. Immediately or 9 h after the high dose-rate irradiation (HDR, 2.5 Gy/min), or immediately after the middle (MDR, 0.039 Gy/min) or low (LDR, 0.00098 Gy/min) dose-rate irradiation, the tumor cells were isolated and incubated with a cytokinesis blocker, and the micronucleus (MN) frequency in cells without BrdU labeling (Q cells) was determined using immunofluorescence staining for BrdU. Results Following γ-ray irradiation, SAS/neo tumor cells, especially intratumor Q cells, showed a marked reduction in sensitivity due to the recovery from radiation-induced damage, compared with the total or Q cells within SAS/mp53 tumors that showed little repair capacity. The recovery capacities following γ-ray irradiation were greater in Q than total cell population and increased in the following order of 9 h after HDR < MDR < LDR. Thus, the difference in radio-sensitivity between the total (P + Q) and Q cells after γ-ray irradiation increased in the same order. Conclusion To secure controlling solid tumors as a whole, difference in sensitivity between total and Q tumor cells especially in solid tumors irrespective of p53 status has to be suppressed as irradiation dose rate decreases, for instance, through employing combined method for enhancing the response of Q tumor cells.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Particle Radiation Biology, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Junya Kobayashi
- Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Keizo Tano
- Particle Radiation Biology, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Yu Sanada
- Particle Radiation Biology, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Minoru Suzuki
- Particle Radiation Oncology, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Koji Ono
- Kansai BNCT Collaborative Research Center, Osaka Medical College, 2-7, Daigaku-cho, Takatsuki, Osaka 569-8686, Japan
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Sanada Y, Sasanuma H, Takeda S, Tano K, Masunaga SI. Disruption of Hif-1α enhances cytotoxic effects of metformin in murine squamous cell carcinoma. Int J Radiat Biol 2017; 94:88-96. [DOI: 10.1080/09553002.2018.1409443] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Yu Sanada
- Particle Radiation Biology, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Kumatori-cho, Osaka, Japan
| | - Hiroyuki Sasanuma
- Department of Radiation Genetics, Kyoto University, Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, Japan
| | - Shunichi Takeda
- Department of Radiation Genetics, Kyoto University, Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, Japan
| | - Keizo Tano
- Particle Radiation Biology, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Kumatori-cho, Osaka, Japan
| | - Shin-ichiro Masunaga
- Particle Radiation Biology, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Kumatori-cho, Osaka, Japan
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Çaglayan M, Prasad R, Krasich R, Longley MJ, Kadoda K, Tsuda M, Sasanuma H, Takeda S, Tano K, Copeland WC, Wilson SH. Complementation of aprataxin deficiency by base excision repair enzymes in mitochondrial extracts. Nucleic Acids Res 2017; 45:10079-10088. [PMID: 28973450 PMCID: PMC5622373 DOI: 10.1093/nar/gkx654] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 07/15/2017] [Indexed: 01/08/2023] Open
Abstract
Mitochondrial aprataxin (APTX) protects the mitochondrial genome from the consequence of ligase failure by removing the abortive ligation product, i.e. the 5′-adenylate (5′-AMP) group, during DNA replication and repair. In the absence of APTX activity, blocked base excision repair (BER) intermediates containing the 5′-AMP or 5′-adenylated-deoxyribose phosphate (5′-AMP-dRP) lesions may accumulate. In the current study, we examined DNA polymerase (pol) γ and pol β as possible complementing enzymes in the case of APTX deficiency. The activities of pol β lyase and FEN1 nucleotide excision were able to remove the 5′-AMP-dRP group in mitochondrial extracts from APTX−/− cells. However, the lyase activity of purified pol γ was weak against the 5′-AMP-dRP block in a model BER substrate, and this activity was not able to complement APTX deficiency in mitochondrial extracts from APTX−/−Pol β−/− cells. FEN1 also failed to provide excision of the 5′-adenylated BER intermediate in mitochondrial extracts. These results illustrate the potential role of pol β in complementing APTX deficiency in mitochondria.
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Affiliation(s)
- Melike Çaglayan
- Genome Integrity and Structural Biology Laboratory, DNA Repair and Nucleic Acid Enzymology Group, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Rajendra Prasad
- Genome Integrity and Structural Biology Laboratory, DNA Repair and Nucleic Acid Enzymology Group, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Rachel Krasich
- Genome Integrity and Structural Biology Laboratory, Mitochondrial DNA Replication Group, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Matthew J Longley
- Genome Integrity and Structural Biology Laboratory, Mitochondrial DNA Replication Group, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Kei Kadoda
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Asashiro-Nishi, Kumatori, Osaka 590-0494 Japan
| | - Masataka Tsuda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida-Konoe, Sakyo, Kyoto 606-8501, Japan
| | - Hiroyuki Sasanuma
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida-Konoe, Sakyo, Kyoto 606-8501, Japan
| | - Shunichi Takeda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida-Konoe, Sakyo, Kyoto 606-8501, Japan
| | - Keizo Tano
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Asashiro-Nishi, Kumatori, Osaka 590-0494 Japan
| | - William C Copeland
- Genome Integrity and Structural Biology Laboratory, Mitochondrial DNA Replication Group, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Samuel H Wilson
- Genome Integrity and Structural Biology Laboratory, DNA Repair and Nucleic Acid Enzymology Group, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
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Masunaga SI, Tano K, Sanada Y, Sakurai Y, Tanaka H, Suzuki M, Kondo N, Watanabe T, Takata T, Maruhashi A, Ono K. Effect of Tirapazamine, Metformin or Mild Hyperthermia on Recovery From Radiation-Induced Damage in Pimonidazole-Unlabeled Quiescent Tumor Cells. World J Oncol 2017; 8:137-146. [PMID: 29147450 PMCID: PMC5687893 DOI: 10.14740/wjon1058w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 09/18/2017] [Indexed: 11/11/2022] Open
Abstract
Background The aim of the study was to examine the effect of tirapazamine (TPZ) on recovery from radiation-induced damage in pimonidazole-unlabeled quiescent (Q) tumor cells compared with that of metformin (Met) or mild temperature hyperthermia (MTH). Methods Proliferating (P) cells in EL4 tumors were labeled by continuous 5-bromo-2'-deoxyuridine (BrdU) administration. Tumors received γ-rays at 1 h after pimonidazole administration followed by Met or TPZ treatment or MTH. Twenty-four hours later, the responses of Q and total (P + Q) cells and those of the pimonidazole-unlabeled cells were assessed with micronucleation and apoptosis frequencies using immunofluorescence staining for BrdU and apoptosis frequency using immunofluorescence staining for pimonidazole, respectively. Results With γ-rays only, the pimonidazole-unlabeled cell fraction showed significantly enhanced radio-sensitivity compared with the whole cell fraction more remarkably in Q than total cells. However, a significantly greater decrease in radio-sensitivity in the pimonidazole-unlabeled than the whole cell fraction, evaluated using a delayed assay, was more clearly observed in Q than total cells. Post-irradiation MTH or Met treatment more clearly repressed the decrease in radio-sensitivity in the Q than total cells. Post-irradiation TPZ administration produced a large radio-sensitizing effect on both total and Q cells, especially on Q cells. In pimonidazole-unlabeled cell fractions in both total and Q cells, TPZ suppressed the reduction in sensitivity much more efficiently than MTH or Met without any radio-sensitizing effect. Conclusion Post-irradiation TPZ administration has the potential to both suppress recovery from radiation-induced damage and enhance the radio-sensitivity both in total and Q tumor cells. Post-irradiation TPZ administration may be useful for controlling tumors.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Particle Radiation Biology, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Keizo Tano
- Particle Radiation Biology, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Yu Sanada
- Particle Radiation Biology, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Yoshinori Sakurai
- Radiation Medical Physics, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Hiroki Tanaka
- Radiation Medical Physics, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Minoru Suzuki
- Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Natsuko Kondo
- Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Tsubasa Watanabe
- Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Takushi Takata
- Radiation Medical Physics, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Akira Maruhashi
- Radiation Medical Physics, Division of Radiation Life Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Koji Ono
- Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
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Kadoda K, Moriwaki T, Tsuda M, Sasanuma H, Ishiai M, Takata M, Ide H, Masunaga SI, Takeda S, Tano K. Selective cytotoxicity of the anti-diabetic drug, metformin, in glucose-deprived chicken DT40 cells. PLoS One 2017; 12:e0185141. [PMID: 28926637 PMCID: PMC5605006 DOI: 10.1371/journal.pone.0185141] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 09/05/2017] [Indexed: 12/14/2022] Open
Abstract
Metformin is a biguanide drug that is widely used in the treatment of diabetes. Epidemiological studies have indicated that metformin exhibits anti-cancer activity. However, the molecular mechanisms underlying this activity currently remain unclear. We hypothesized that metformin is cytotoxic in a tumor-specific environment such as glucose deprivation and/or low oxygen (O2) tension. We herein demonstrated that metformin was highly cytotoxic under glucose-depleted, but not hypoxic (2% O2) conditions. In order to elucidate the underlying mechanisms of this selective cytotoxicity, we treated exposed DNA repair-deficient chicken DT40 cells with metformin under glucose-depleted conditions and measured cellular sensitivity. Under glucose-depleted conditions, metformin specifically killed fancc and fancl cells that were deficient in FANCC and FANCL proteins, respectively, which are involved in DNA interstrand cross-link repair. An analysis of chromosomal aberrations in mitotic chromosome spreads revealed that a clinically relevant concentration of metformin induced DNA double-strand breaks (DSBs) in fancc and fancl cells under glucose-depleted conditions. In summary, metformin induced DNA damage under glucose-depleted conditions and selectively killed cells. This metformin-mediated selective toxicity may suppress the growth of malignant tumors that are intrinsically deprived of glucose.
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Affiliation(s)
- Kei Kadoda
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Kumatori, Osaka, Japan
| | - Takahito Moriwaki
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Kumatori, Osaka, Japan
| | - Masataka Tsuda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Hiroyuki Sasanuma
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Masamichi Ishiai
- Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Minoru Takata
- Department of Late Effects Studies, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Hiroshi Ide
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan
| | - Shin-ichiro Masunaga
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Kumatori, Osaka, Japan
| | - Shunichi Takeda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Keizo Tano
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Kumatori, Osaka, Japan
- * E-mail:
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Moriwaki T, Okamoto S, Sasanuma H, Nagasawa H, Takeda S, Masunaga SI, Tano K. Cytotoxicity of Tirapazamine (3-Amino-1,2,4-benzotriazine-1,4-dioxide)-Induced DNA Damage in Chicken DT40 Cells. Chem Res Toxicol 2016; 30:699-704. [PMID: 27943678 DOI: 10.1021/acs.chemrestox.6b00417] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Tirapazamine (TPZ) is an anticancer drug with highly selective cytotoxicity toward hypoxic cells. TPZ is converted to a radical intermediate under hypoxic conditions, and this intermediate interacts with intracellular macromolecules, including DNA. TPZ has been reported to indirectly induce DNA double-strand breaks (DSBs) through the formation of various intermediate DNA lesions under hypoxic conditions. Although the topoisomerase II-DNA complex has been identified as one of these intermediates, other lesions have not yet been defined. In order to obtain a deeper understanding of the mechanisms responsible for the selective cytotoxicity of TPZ toward hypoxic cells, its cellular sensitivity was systematically examined with genetically isogenic DNA-repair-deficient mutant DT40 cell lines. Our results showed that tdp1-/-, tdp2-/-, parp1-/-, and aptx1-/- cells displayed hypersensitivity to TPZ only under hypoxic conditions. These results strongly suggest that the accumulation of the topoisomerase I-trapped DNA complex, topoisomerase II-trapped DNA complex, and abortive ligation products with 5'-AMP are the potential causes of TPZ-induced hypoxic cell death. Furthermore, our genetic analysis revealed that under normoxic conditions (as well as hypoxic conditions), TPZ exhibited significant cytotoxicity toward cell lines deficient in homologous recombination, nonhomologous end joining, base excision repair, and translesion synthesis. Ascorbic acid, a radical scavenger, suppressed TPZ-induced cytotoxicity toward normoxic cells. These results suggest the involvement of oxidative DNA damage and DSBs produced by reactive oxygen species generated from superoxide, a byproduct of the oxidation of TPZ radical intermediates in normoxic cells. Collectively, our results demonstrate that TPZ induces oxidative DNA damage under normoxic and hypoxic conditions and selectively introduces abortive topoisomerase-DNA complexes and unligatable DNA ends under hypoxic conditions.
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Affiliation(s)
- Takahito Moriwaki
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University , 2 Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Saki Okamoto
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University , 2 Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Hiroyuki Sasanuma
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University , Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hideko Nagasawa
- Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University , 1-25-4 Daigaku-nishi, Gifu-shi, Gifu 501-1196, Japan
| | - Shunichi Takeda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University , Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Shin-Ichiro Masunaga
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University , 2 Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Keizo Tano
- Division of Radiation Life Science, Research Reactor Institute, Kyoto University , 2 Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
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Masunaga S, Tano K, Sanada Y, Sakurai Y, Tanaka H, Suzuki M, Maruhashi A, Ono K. Radiosensitivity and Capacity to Recover from Radiation-Induced Damage in Pimonidazole-Unlabeled Oxygenated Intratumor Quiescent Cells Depend on p53 Status of Tumor Cells. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2016.06.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Masunaga SI, Tatebe H, Nishimura Y, Tano K, Sanada Y, Moriwaki T, Sakurai Y, Tanaka H, Suzuki M, Kondo N, Maruhashi A, Ono K. Effect of oxygen pressure during incubation with a10B-carrier on10B uptake capacity of culturedp53 wild-type andmutatedtumor cells: dependency onp53status of tumor cells and types of10B-carriers. Int J Radiat Biol 2016; 92:187-94. [DOI: 10.3109/09553002.2016.1137104] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Masunaga S, Tano K, Sanada Y, Sakurai Y, Tanaka H, Suzuki M, Kondo N, Narabayashi M, Watanabe T, Nakagawa Y, Maruhashi A, Ono K. The effect of fractionated administration of thalidomide at γ-ray irradiation on tumor response and lung metastasis. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)30148-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Masunaga SI, Uzawa A, Hirayama R, Matsumoto Y, Sakurai Y, Tanaka H, Tano K, Sanada Y, Suzuki M, Maruhashi A, Ono K. The Effect of p53 Status of Tumor Cells on Radiosensitivity of Irradiated Tumors With Carbon-Ion Beams Compared With γ-Rays or Reactor Neutron Beams. World J Oncol 2015; 6:398-409. [PMID: 28983338 PMCID: PMC5624688 DOI: 10.14740/wjon941w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2015] [Indexed: 11/13/2022] Open
Abstract
Background The aim of the study was to clarify the effect of p53 status of tumor cells on radiosensitivity of solid tumors following accelerated carbon-ion beam irradiation compared with γ-rays or reactor neutron beams, referring to the response of intratumor quiescent (Q) cells. Methods Human head and neck squamous cell carcinoma cells transfected with mutant TP53 (SAS/mp53) or with neo vector (SAS/neo) were injected subcutaneously into hind legs of nude mice. Tumor-bearing mice received 5-bromo-2’-deoxyuridine (BrdU) continuously to label all intratumor proliferating (P) cells. They received γ-rays or accelerated carbon-ion beams at a high or reduced dose-rate. Other tumor-bearing mice received reactor thermal or epithermal neutrons at a reduced dose-rate. Immediately or 9 hours after the high dose-rate irradiation (HDRI), or immediately after the reduced dose-rate irradiation (RDRI), the tumor cells were isolated and incubated with a cytokinesis blocker, and the micronucleus (MN) frequency in cells without BrdU labeling (Q cells) was determined using immunofluorescence staining for BrdU. Results The difference in radiosensitivity between the total (P + Q) and Q cells after γ-ray irradiation was markedly reduced with reactor neutron beams or carbon-ion beams, especially with a higher linear energy transfer (LET) value. Following γ-ray irradiation, SAS/neo tumor cells, especially intratumor Q cells, showed a marked reduction in sensitivity due to the recovery from radiation-induced damage, compared with the total or Q cells within SAS/mp53 tumors that showed little repair capacity. In both total and Q cells within both SAS/neo and SAS/mp53 tumors, carbon-ion beam irradiation, especially with a higher LET, showed little recovery capacity through leaving an interval between HDRI and the assay or decreasing the dose-rate. The recovery from radiation-induced damage after γ-ray irradiation was a p53-dependent event, but little recovery was found after carbon-ion beam irradiation. With RDRI, the radiosensitivity to reactor thermal and epithermal neutron beams was slightly higher than that to carbon-ion beams. Conclusion For tumor control, including intratumor Q-cell control, accelerated carbon-ion beams, especially with a higher LET, and reactor thermal and epithermal neutron beams were very useful for suppressing the recovery from radiation-induced damage irrespective of p53 status of tumor cells.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Particle Radiation Biology, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Akiko Uzawa
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Ryoichi Hirayama
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Yoshitaka Matsumoto
- Proton Medical Research Center, Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Yoshinori Sakurai
- Radiation Medical Physics, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Hiroki Tanaka
- Radiation Medical Physics, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Keizo Tano
- Particle Radiation Biology, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Yu Sanada
- Particle Radiation Biology, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Minoru Suzuki
- Particle Radiation Oncology, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Akira Maruhashi
- Radiation Medical Physics, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Koji Ono
- Particle Radiation Oncology, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
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Sakai T, Koyanagi M, Nakae N, Notani M, Tano K, Kimura Y, Sanada Y, Kato S, Hirozane N. Muscle activity during knee extension training in the prone position putting the fulcrum in the distal leg in osteoarthritis patients. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.1243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Masunaga S, Sakurai Y, Tano K, Tanaka H, Suzuki M, Kondo N, Narabayashi M, Watanabe T, Nakagawa Y, Maruhashi A, Ono K. Significance of Administering Bevacizumab Combined With Boron Neutron Capture Therapy in Terms of Local Tumor Control and Lung Metastatic Potential. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.2301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Masunaga SI, Sanada Y, Moriwaki T, Tano K, Sakurai Y, Tanaka H, Suzuki M, Kondo N, Narabayashi M, Watanabe T, Nakagawa Y, Maruhashi A, Ono K. Significance of Fractionated Administration of Thalidomide Combined With γ-Ray Irradiation in Terms of Local Tumor Response and Lung Metastasis. World J Oncol 2014; 5:155-165. [PMID: 29147396 PMCID: PMC5649741 DOI: 10.14740/wjon855w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2014] [Indexed: 12/02/2022] Open
Abstract
Background The aim of this study was to evaluate the significance of fractionated administration of thalidomide combined with γ-ray irradiation in terms of local tumor response and lung metastatic potential, referring to the response of intratumor quiescent (Q) cells. Methods B16-BL6 melanoma tumor-bearing C57BL/6 mice were continuously given 5-bromo-2’-deoxyuridine (BrdU) to label all proliferating (P) cells. The tumor-bearing mice then received γ-ray irradiation after thalidomide treatment through a single or two consecutive daily intraperitoneal administrations up to a total dose of 400 mg/kg in combination with an acute hypoxia-releasing agent (nicotinamide) or mild temperature hyperthermia (MTH). Immediately after the irradiation, cells from some tumors were isolated and incubated with a cytokinesis blocker. The responses of the Q and total (= P + Q) cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In other tumor-bearing mice, 17 days after irradiation, macroscopic lung metastases were enumerated. Results Thalidomide raised the sensitivity of the total cell population more remarkably than Q cells in both single and daily administrations. Daily administration of thalidomide elevated the sensitivity of both the total and Q cell populations, but especially the total cell population, compared with single administration. Daily administration, especially combined with MTH, decreased the number of lung metastases. Conclusion Daily fractionated administration of thalidomide in combination with γ-ray irradiation was thought to be more promising than single administration because of its potential to enhance local tumor response and repress lung metastatic potential.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Yu Sanada
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Takahiro Moriwaki
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Keizo Tano
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Yoshinori Sakurai
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Hiroki Tanaka
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Minoru Suzuki
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Natsuko Kondo
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Masaru Narabayashi
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Tsubasa Watanabe
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Yosuke Nakagawa
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Akira Maruhashi
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Koji Ono
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
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Masunaga SI, Sakurai Y, Tano K, Tanaka H, Suzuki M, Kondo N, Narabayashi M, Watanabe T, Nakagawa Y, Maruhashi A, Ono K. Effect of bevacizumab combined with boron neutron capture therapy on local tumor response and lung metastasis. Exp Ther Med 2014; 8:291-301. [PMID: 24944637 PMCID: PMC4061189 DOI: 10.3892/etm.2014.1704] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 04/14/2014] [Indexed: 01/03/2023] Open
Abstract
The aim of the present study was to evaluate the effect of bevacizumab on local tumor response and lung metastatic potential during boron neutron capture therapy (BNCT) and in particular, the response of intratumor quiescent (Q) cells. B16-BL6 melanoma tumor-bearing C57BL/6 mice were continuously administered bromodeoxyuridine (BrdU) to label all proliferating (P) tumor cells. The tumors were irradiated with thermal neutron beams following the administration of a 10B-carrier [L-para-boronophenylalanine-10B (BPA) or sodium mercaptoundecahydrododecaborate-10B (BSH)], with or without the administration of bevacizumab. This was further combined with an acute hypoxia-releasing agent (nicotinamide) or mild temperature hyperthermia (MTH, 40°C for 60 min). Immediately following the irradiation, cells from certain tumors were isolated and incubated with a cytokinesis blocker. The responses of the Q cells and the total (P+Q) cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In other tumor-bearing mice, 17 days following irradiation, lung metastases were enumerated. Three days following bevacizumab administration, the sensitivity of the total tumor cell population following BPA-BNCT had increased more than that following BSH-BNCT. The combination with MTH, but not with nicotinamide, further enhanced total tumor cell population sensitivity. Regardless of the presence of a 10B-carrier, MTH enhanced the sensitivity of the Q cell population. Regardless of irradiation, the administration of bevacizumab, as well as nicotinamide treatment, demonstrated certain potential in reducing the number of lung metastases especially in BPA-BNCT compared with BSH-BNCT. Thus, the current study revealed that BNCT combined with bevacizumab has the potential to sensitize total tumor cells and cause a reduction in the number of lung metastases to a similar level as nicotinamide.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Yoshinori Sakurai
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Keizo Tano
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Hiroki Tanaka
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Minoru Suzuki
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Natsuko Kondo
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Masaru Narabayashi
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Tsubasa Watanabe
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Yosuke Nakagawa
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Akira Maruhashi
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
| | - Koji Ono
- Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan
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Tano K, Yasuda S, Umezawa A, Sato Y. A highly efficient culture method for growth and detection of undifferentiated human pluripotent stem cells present as impurities in cell-processed therapeutic products. Cytotherapy 2014. [DOI: 10.1016/j.jcyt.2014.01.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Masunaga SI, Sakurai Y, Tanaka H, Tano K, Suzuki M, Kondo N, Narabayashi M, Nakagawa Y, Watanabe T, Maruhashi A, Ono K. The dependency of compound biological effectiveness factors on the type and the concentration of administered neutron capture agents in boron neutron capture therapy. Springerplus 2014; 3:128. [PMID: 25674433 PMCID: PMC4320213 DOI: 10.1186/2193-1801-3-128] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 02/20/2014] [Indexed: 12/02/2022]
Abstract
Purpose To examine the effect of the type and the concentration of neutron capture agents on the values of compound biological effectiveness (CBE) in boron neutron capture therapy. Methods and materials After the subcutaneous administration of a 10B-carrier, boronophenylalanine-10B (BPA) or sodium mercaptododecaborate-10B (BSH), at 3 separate concentrations, the 10B concentrations in tumors were measured by γ-ray spectrometry. SCC VII tumor-bearing C3H/He mice received 5-bromo-2′-deoxyuridine (BrdU) continuously to label all intratumor proliferating (P) cells, then treated with BPA or BSH. Immediately after reactor neutron beam irradiation, during which intratumor 10B concentrations were kept at levels similar to each other, cells from some tumors were isolated and incubated with a cytokinesis blocker. The responses of BrdU-unlabeled quiescent (Q) and total (= P + Q) tumor cells were assessed based on the frequencies of micronucleation using immunofluorescence staining for BrdU. Results The CBE values were higher in Q cells and in the use of BPA than total cells and BSH, respectively. In addition, the higher the administered concentrations were, the smaller the CBE values became, with a clearer tendency in the use of BPA than BSH. The values for neutron capture agents that deliver into solid tumors more dependently on uptake capacity of tumor cells became more changeable. Conclusion Tumor characteristics, such as micro-environmental heterogeneity, stochastic genetic or epigenetic changes, or hierarchical organization of tumor cells, are thought to partially influence on the value of CBE, meaning that the CBE value itself may be one of the indices showing the degree of tumor heterogeneity.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Yoshinori Sakurai
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Hiroki Tanaka
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Keizo Tano
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Minoru Suzuki
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Natsuko Kondo
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Masaru Narabayashi
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Yosuke Nakagawa
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Tsubasa Watanabe
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Akira Maruhashi
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
| | - Koji Ono
- Particle Radiation Biology, Department of Radiation Life and Medical Science, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494 Japan
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Masaoka A, Gassman NR, Horton JK, Kedar PS, Witt KL, Hobbs CA, Kissling GE, Tano K, Asagoshi K, Wilson SH. Interaction between DNA Polymerase β and BRCA1. PLoS One 2013; 8:e66801. [PMID: 23826138 PMCID: PMC3694962 DOI: 10.1371/journal.pone.0066801] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 05/13/2013] [Indexed: 11/18/2022] Open
Abstract
The breast cancer 1 (BRCA1) protein is a tumor suppressor playing roles in DNA repair and cell cycle regulation. Studies of DNA repair functions of BRCA1 have focused on double-strand break (DSB) repair pathways and have recently included base excision repair (BER). However, the function of BRCA1 in BER is not well defined. Here, we examined a BRCA1 role in BER, first in relation to alkylating agent (MMS) treatment of cells and the BER enzyme DNA polymerase β (pol β). MMS treatment of BRCA1 negative human ovarian and chicken DT40 cells revealed hypersensitivity, and the combined gene deletion of BRCA1 and pol β in DT40 cells was consistent with these factors acting in the same repair pathway, possibly BER. Using cell extracts and purified proteins, BRCA1 and pol β were found to interact in immunoprecipitation assays, yet in vivo and in vitro assays for a BER role of BRCA1 were negative. An alternate approach with the human cells of immunofluorescence imaging and laser-induced DNA damage revealed negligible BRCA1 recruitment during the first 60 s after irradiation, the period typical of recruitment of pol β and other BER factors. Instead, 15 min after irradiation, BRCA1 recruitment was strong and there was γ-H2AX co-localization, consistent with DSBs and repair. The rapid recruitment of pol β was similar in BRCA1 positive and negative cells. However, a fraction of pol β initially recruited remained associated with damage sites much longer in BRCA1 positive than negative cells. Interestingly, pol β expression was required for BRCA1 recruitment, suggesting a partnership between these repair factors in DSB repair.
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Affiliation(s)
- Aya Masaoka
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, North Carolina, United States of America
| | - Natalie R. Gassman
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, North Carolina, United States of America
| | - Julie K. Horton
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, North Carolina, United States of America
| | - Padmini S. Kedar
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, North Carolina, United States of America
| | - Kristine L. Witt
- National Toxicology Program, NIEHS, National Institutes of Health, North Carolina, United States of America
| | - Cheryl A. Hobbs
- Integrated Laboratory Systems, Inc., North Carolina, United States of America
| | - Grace E. Kissling
- Biostatistics Branch, NIEHS, National Institutes of Health, North Carolina, United States of America
| | - Keizo Tano
- Department of Radiation Life Science and Radiation Medical Science, Kyoto University Research Reactor Institute, Kumatori, Japan
| | - Kenjiro Asagoshi
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, North Carolina, United States of America
| | - Samuel H. Wilson
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, North Carolina, United States of America
- * E-mail:
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Kashino G, Tamari Y, Kumagai J, Tano K, Watanabe M. Suppressive effect of ascorbic acid on the mutagenesis induced by the bystander effect through mitochondrial function. Free Radic Res 2013; 47:474-9. [DOI: 10.3109/10715762.2013.791025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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26
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Masunaga SI, Sakurai Y, Tanaka H, Suzuki M, Kondo N, Narabayashi M, Tano K, Maruhashi A, Ono K. Usefulness of Daily Fractionated Administration of Wortmannin Combined With γ-Ray Irradiation in Terms of Local Tumor Response and Lung Metastasis. World J Oncol 2013; 4:26-36. [PMID: 29147327 PMCID: PMC5649916 DOI: 10.4021/wjon640w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2013] [Indexed: 11/30/2022] Open
Abstract
Background To evaluate the usefulness of fractionated administration of wortmannin combined with γ-ray irradiation in terms of local tumor response and lung metastatic potential, referring to the response of intratumor quiescent (Q) cells. Methods B16-BL6 melanoma tumor-bearing C57BL/6 mice were continuously given 5-bromo-2’-deoxyuridine (BrdU) to label all proliferating (P) cells. The tumor-bearing mice then received γ-ray irradiation after wortmannin treatment through a single or 4 consecutive daily intraperitoneal administrations up to a total dose of 4 mg/kg in combination with an acute hypoxia-releasing agent (nicotinamide) or mild temperature hyperthermia (MTH). Immediately after the irradiation, cells from some tumors were isolated and incubated with a cytokinesis blocker. The responses of the Q and total (= P + Q) cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In other tumor-bearing mice, 17 days after irradiation, macroscopic lung metastases were enumerated. Results Wortmannin raised the sensitivity of Q cells more remarkably than the total cell population in both single and daily administrations. Daily administration of wortmannin elevated the sensitivity of both the total and Q cell populations, but especially the total cell population, compared with single administration. Daily administration, especially combined with MTH, decreased the number of lung metastases. Conclusion Daily fractionated administration of wortmannin in combination with γ-ray irradiation was thought to be more promising than single administration because of its potential to enhance local tumor response and repress lung metastatic potential.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Yoshinori Sakurai
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Hiroki Tanaka
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Minoru Suzuki
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Natsuko Kondo
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Masaru Narabayashi
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Keizo Tano
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Akira Maruhashi
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Koji Ono
- Radiation Life and Medical Science Research Division, Research Reactor Institute, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
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Tamari Y, Nawata H, Inoue E, Yoshimura A, Yoshii H, Kashino G, Seki M, Enomoto T, Watanabe M, Tano K. Protective roles of ascorbic acid in oxidative stress induced by depletion of superoxide dismutase in vertebrate cells. Free Radic Res 2012; 47:1-7. [DOI: 10.3109/10715762.2012.734916] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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28
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Okada T, Kashino G, Nishiura H, Tano K, Watanabe M. Micronuclei formation induced by X-ray irradiation does not always result from DNA double-strand breaks. J Radiat Res 2012; 53:93-100. [PMID: 22240940 DOI: 10.1269/jrr.11147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
X-ray induced formation of micronuclei is generally thought to result from DNA double-strand breaks (DSBs). However, DNA DSBs inhibit the cell cycle progression that is required for micronucleus formation. In order to reconcile this apparent discrepancy, we investigated whether DNA DSBs induced during the G1 phase could lead to micronucleus formation. We irradiated human embryonic (HE17) cells that had been treated with a radical scavenger, either DMSO or ascorbic acid (AsA), and determined the level of suppression of DNA DSBs or micronuclei. When DNA DSBs were evaluated using 53BP1 foci, treatment with 5 mM AsA did not inhibit the numbers of foci at various intervals after X-ray irradiation; however, treatment with 5 mM or 256 mM DMSO did have a significant inhibitory effect. By contrast, an assay of micronucleus numbers showed that treatment with 5 mM or 256 mM DMSO before X-ray irradiation resulted in almost no inhibition of micronucleus formation, but treatment with 5 mM AsA did have a significant inhibitory effect. These results clearly showed that AsA could suppress micronucleus formation, although it was not effective for suppression of DNA DSBs. Therefore, we conclude that DNA DSBs induced in the G1 phase do not directly lead to micronucleus formation.
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Affiliation(s)
- Takuya Okada
- Laboratory of Radiation Biology, Research Reactor Institute, Kyoto University, Japan
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29
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Abstract
We successfully identified the bystander effect in B16 murine melanoma cells exposed to UVA irradiation. The effect was identified based on melanogenesis following the medium transfer of the B16 cells, which had been cultured for 24 h after being exposed to UVA irradiation, to nonirradiated cells (bystander cells). Our confirmation study of the functional mechanism of bystander cells confirmed the reduced levels of mitochondrial membrane potential 1-4 h after the medium transfer. In addition, we observed increased levels of intracellular oxidation after 9-12 h, and the generation of melanin radicals, including long-lived radicals, 24 h after medium transfer. Further analysis of bystander factors revealed that the administration of EGTA treatment at the time of medium transfer led to an inhibition of melanogenesis and to neutralization of the mitochondrial membrane potential level, as well as to the restoration of intracellular oxidation levels to those of controls. The results demonstrated that the UVA irradiation bystander effect in B16 cells, as indicated by melanogenesis, was induced by the increase in intracellular oxidation due to the mitochondrial activity of calcium ions, which were among the bystander factors involved in the increase.
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Affiliation(s)
- Hideki Nishiura
- Division of Radiation Life Science, Department of Radiation Life Science and Radiation Medical Science, Kyoto University Research Reactor Institute, Sennan-gun, Osaka, Japan
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30
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Nawata H, Kashino G, Tano K, Daino K, Shimada Y, Kugoh H, Oshimura M, Watanabe M. Dysregulation of gene expression in the artificial human trisomy cells of chromosome 8 associated with transformed cell phenotypes. PLoS One 2011; 6:e25319. [PMID: 21980425 PMCID: PMC3183047 DOI: 10.1371/journal.pone.0025319] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 08/31/2011] [Indexed: 11/26/2022] Open
Abstract
A change in chromosome number, known as aneuploidy, is a common characteristic of cancer. Aneuploidy disrupts gene expression in human cancer cells and immortalized human epithelial cells, but not in normal human cells. However, the relationship between aneuploidy and cancer remains unclear. To study the effects of aneuploidy in normal human cells, we generated artificial cells of human primary fibroblast having three chromosome 8 (trisomy 8 cells) by using microcell-mediated chromosome transfer technique. In addition to decreased proliferation, the trisomy 8 cells lost contact inhibition and reproliferated after exhibiting senescence-like characteristics that are typical of transformed cells. Furthermore, the trisomy 8 cells exhibited chromosome instability, and the overall gene expression profile based on microarray analyses was significantly different from that of diploid human primary fibroblasts. Our data suggest that aneuploidy, even a single chromosome gain, can be introduced into normal human cells and causes, in some cases, a partial cancer phenotype due to a disruption in overall gene expression.
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Affiliation(s)
- Hisakatsu Nawata
- Laboratory of Radiation Biology, Research Reactor Institute, Kyoto University, Osaka, Japan
| | - Genro Kashino
- Advanced Molecular Imaging Center, Medical School, Oita University, Oita, Japan
| | - Keizo Tano
- Laboratory of Radiation Biology, Research Reactor Institute, Kyoto University, Osaka, Japan
| | - Kazuhiro Daino
- Experimental Radiobiology for Children's Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Yoshiya Shimada
- Experimental Radiobiology for Children's Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Hiroyuki Kugoh
- Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Sciences, Tottori University, Tottori, Japan
| | - Mitsuo Oshimura
- Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Sciences, Tottori University, Tottori, Japan
| | - Masami Watanabe
- Laboratory of Radiation Biology, Research Reactor Institute, Kyoto University, Osaka, Japan
- * E-mail:
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31
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Tano K, Hamamoto H, Ito T, Sumiya E, Rakwal R, Shibato J, Masuo Y, Ijiri K, Sekimizu K, Akimitsu N. Reduced expression of Sytl 1 and Ccdc21 and impaired induction of Mt I by oxidative stress in SII-K1 knockout mice. Drug Discov Ther 2010; 4:368-372. [PMID: 22491241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
SII-K1 is a member of the transcription elongation factor S-II family. In the mouse, SII-K1 is expressed exclusively in the liver, kidney, heart, and skeletal muscle. Here, we report that deletion of the SII-K1 gene in mice resulted in the downregulation of the synaptotagmin-like 1 (Sytl 1) gene in liver and of the coiled-coil domain-containing 21 (Ccdc21) gene in liver and kidney. Moreover, the induction of the metallothionein I (Mt I) gene in SII-K1-deficient mice liver was impaired in diethyl maleate-induced oxidative stress conditions. Our results suggest that SII-K1 regulates these genes in vivo.
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Affiliation(s)
- K Tano
- Radioisotope Center, The University of Tokyo, Tokyo, Japan
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Inoue E, Tano K, Yoshii H, Nakamura J, Tada S, Watanabe M, Seki M, Enomoto T. SOD1 Is Essential for the Viability of DT40 Cells and Nuclear SOD1 Functions as a Guardian of Genomic DNA. J Nucleic Acids 2010; 2010. [PMID: 20811569 PMCID: PMC2929635 DOI: 10.4061/2010/795946] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Accepted: 06/04/2010] [Indexed: 11/20/2022] Open
Abstract
Reactive oxygen species (ROSs) are produced during normal cellular metabolism, particularly by respiration in mitochondria, and these ROSs are considered to cause oxidative damage to macromolecules, including DNA. In our previous paper, we found no indication that depletion of mitochondrial superoxide dismutase, SOD2, resulted in an increase in DNA damage. In this paper, we examined SOD1, which is distributed in the cytoplasm, nucleus, and mitochondrial intermembrane space. We generated conditional SOD1 knockout cells from chicken DT40 cells and analyzed their phenotypes. The results revealed that SOD1 was essential for viability and that depletion of SOD1, especially nuclear SOD1, increased sister chromatid exchange (SCE) frequency, suggesting that superoxide is generated in or near the nucleus and that nuclear SOD1 functions as a guardian of the genome. Furthermore, we found that ascorbic acid could offset the defects caused by SOD1 depletion, including cell lethality and increases in SCE frequency and apurinic/apyrimidinic sites.
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Affiliation(s)
- Eri Inoue
- Molecular Cell Biology Laboratory, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
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Asagoshi K, Tano K, Chastain PD, Adachi N, Sonoda E, Kikuchi K, Koyama H, Nagata K, Kaufman DG, Takeda S, Wilson SH, Watanabe M, Swenberg JA, Nakamura J. FEN1 functions in long patch base excision repair under conditions of oxidative stress in vertebrate cells. Mol Cancer Res 2010; 8:204-15. [PMID: 20145043 DOI: 10.1158/1541-7786.mcr-09-0253] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
From in vitro studies, flap endonuclease 1 (FEN1) has been proposed to play a role in the long patch (LP) base excision repair (BER) subpathway. Yet the role of FEN1 in BER in the context of the living vertebrate cell has not been thoroughly explored. In the present study, we cloned a DT40 chicken cell line with a deletion in the FEN1 gene and found that these FEN1-deficient cells exhibited hypersensitivity to H(2)O(2). This oxidant produces genotoxic lesions that are repaired by BER, suggesting that the cells have a deficiency in BER affecting survival. In experiments with extracts from the isogenic FEN1 null and wild-type cell lines, the LP-BER activity of FEN1 null cells was deficient, whereas repair by the single-nucleotide BER subpathway was normal. Other consequences of the FEN1 deficiency were also evaluated. These results illustrate that FEN1 plays a role in LP-BER in higher eukaryotes, presumably by processing the flap-containing intermediates of BER.
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Affiliation(s)
- Kenjiro Asagoshi
- Laboratory of Structural Biology, NIEHS, NIH, Research Triangle Park, North Carolina, USA
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Kashino G, Liu Y, Suzuki M, Masunaga SI, Kinashi Y, Ono K, Tano K, Watanabe M. An alternative mechanism for radioprotection by dimethyl sulfoxide; possible facilitation of DNA double-strand break repair. J Radiat Res 2010; 51:733-40. [PMID: 21116101 DOI: 10.1269/jrr.09106] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The radioprotective effects of dimethyl sulfoxide (DMSO) have been known for many years, and the suppression of hydroxyl (OH) radicals induced by ionizing radiation has been thought to be the main cause of this effect. However, the DMSO concentration used was very high, and might be toxic, in earlier studies. In the present study, we administered a lower, non-toxic concentration (0.5%, i.e., 64 mM) of DMSO before irradiation and examined its radioprotective effects. Colony formation assay and micronucleus assay showed significant radioprotective effects in CHO, but not in xrs5, which is defective in the repair function of DNA double-strand breaks. The levels of phosphorylated H2AX and the formation of 53BP1 foci 15 minutes after irradiation, which might reflect initial DNA double-strand breaks, in DMSO-treated CHO cells were similar to those in non-treated cells, suggesting that the radioprotective effects were not attributable to the suppression of general indirect action in the lower concentration of DMSO. On the other hand, 2 hours after irradiation, the average number of 53BP1 foci, which might reflect residual DNA double-strand breaks, was significantly decreased in DMSO-treated CHO cells compared to non-treated cells. The results indicated that low concentration of DMSO exerts radioprotective effects through the facilitation of DNA double-strand break repair rather than through the suppression of indirect action.
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Affiliation(s)
- Genro Kashino
- Laboratory of Radiation Biology, Research Reactor Institute, Kyoto University, Osaka, Japan.
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35
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Masunaga SI, Tano K, Nakamura J, Watanabe M, Kashino G, Suzuki M, Kinashi Y, Ono K. Adverse effect of mild temperature hyperthermia combined with hexamethylenetetramine compared to its effect combined with tirapazamine in the treatment of solid tumors. Exp Ther Med 2010; 1:169-174. [PMID: 23136610 DOI: 10.3892/etm_00000027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Accepted: 08/20/2009] [Indexed: 11/05/2022] Open
Abstract
This study aimed to assess the effect on solid tumors of mild temperature hyperthermia (MTH) combined with hexamethylenetetramine (HMTA) or tirapazamine (TPZ). Squamous cell carcinoma (SCC VII) tumor-bearing mice were continuously administered 5-bromo-2'-deoxyuridine (BrdU) to label intratumor proliferating (P) cells. Mice received HMTA or TPZ through intraperitoneal single or subcutaneous continuous administration, with or without MTH (40°C, 60 min), followed or not by γ-ray irradiation or cisplatin treatment. After HMTA or TPZ administration without γ-ray irradiation or cisplatin treatment, immediately after γ-ray irradiation, or 1 h after cisplatin treatment, the response of quiescent (Q) cells was assessed in terms of micronucleus frequency using immunofluorescence staining for BrdU. The response of the total (P + Q) tumor cells was determined based on a comparison with non-BrdU-treated tumors. Without MTH, HMTA and TPZ had a nearly equal radiosensitizing and cisplatin sensitivity-enhancing effect on both total and Q cells. With MTH, radio- and cisplatin-sensitizing effects by HMTA were reduced, particularly in the Q cells. In contrast, the enhancing effects of TPZ were increased, particularly in the Q cells. Continuous administration of HMTA and TPZ resulted in higher radio- and cisplatin-sensitizing effects than intraperitoneal single administration. In terms of tumor cytotoxicity as a whole, including Q cells, the administration of γ-ray irradiation or cisplatin treatment combined with continuous HMTA administration is promising, taking into account the clinical use of HMTA. However, MTH should not be combined with HMTA administration.
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Tano K, Ichikawa Y, Kinoshita H. [Thoracic aortic rupture resulting from methicillin-resistant Staphylococcus aureus infection: report of a case]. Kyobu Geka 2009; 62:1166-1169. [PMID: 19999096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report a successful surgical treatment of an aortic arch rupture caused by methicillin-resistant Staphylococcus aureus (MRSA) infection in a 72 years old man who had back pain and hemoptysis as symptoms. Computed tomography showed enlargement of the aortic arch within just 4 days. We diagnosed the state of impending rupture of inflammatory aneurysm and performed emergent operation. The upper lobe of the left lung adhered firmly to the site of rupture and sealed as the barrier to prevent bleeding. The aorta was replaced with a dacron graft in situ after entire resection of infected tissue and sufficient irrigation of the pleural cavity. The patient was treated with vancomycin and minocyclin for MRSA infection. The postoperative course of the patient was uneventful. This suggests that an early operation and a proper use of antibiotics lead to a successful clinical result in patient with infectious aortic rupture.
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Affiliation(s)
- K Tano
- Department of Cardiovascular Surgery, Japanese Red Cross Society Kochi Hospital, Kochi, Japan
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Masunaga SI, Tano K, Nakamura J, Watanabe M, Kashino G, Takahashi A, Tanaka H, Suzuki M, Ohnishi K, Kinashi Y, Liu Y, Ohnishi T, Ono K. Usefulness of hexamethylenetetramine as an adjuvant to radiation and cisplatin in the treatment of solid tumors: its independency of p53 status. J Radiat Res 2009; 51:27-35. [PMID: 19801892 DOI: 10.1269/jrr.09072] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The usefulness of hexamethylenetetramine as an adjuvant to radiation and cisplatin in the treatment of solid tumors and its dependency on the p53 status of tumor cells were examined. Human head and neck squamous cell carcinoma cells transfected with mutant TP53 (SAS/mp53), or with neo vector as a control (SAS/neo), were inoculated subcutaneously into both the hind legs of Balb/cA nude mice. The tumor-bearing mice received 5-bromo-2'-deoxyuridine (BrdU) continuously to label all proliferating (P) cells in the tumors. Then, they received hexamethylenetetramine (HMTA), intraperitoneally or continuously, combined with or without gamma-ray irradiation or cisplatin treatment. Immediately after treatment following HMTA, the response of quiescent (Q) cells was assessed in terms of the micronucleus frequency using immunofluorescence staining for BrdU. The response of the total (= P + Q) tumor cells was determined from the BrdU non-treated tumors. A higher toxicity of HMTA to Q cells than total cells, especially in SAS/neo, was made less clear by continuous administration. There was no apparent difference in the radio- and cisplatin-sensitivity enhancing effects by HMTA combination between SAS/neo and SAS/mp53 tumors, with a slightly greater effect in SAS/mp53. In both SAS/neo and SAS/mp53 tumors, continuous HMTA administration produced higher radio- and cisplatin-sensitivity enhancing effects than intraperitoneal single administration. Therefore, the use of HMTA as an adjuvant to radiation or cisplatin might be promising in curing solid tumors with large fraction of hypoxic cells and also with frequent loss-of-function in p53.
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Affiliation(s)
- Shin-ichiro Masunaga
- Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, Kumatori, Osaka, Japan.
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Pachkowski BF, Tano K, Afonin V, Elder RH, Takeda S, Watanabe M, Swenberg JA, Nakamura J. Cells deficient in PARP-1 show an accelerated accumulation of DNA single strand breaks, but not AP sites, over the PARP-1-proficient cells exposed to MMS. Mutat Res 2009; 671:93-9. [PMID: 19778542 DOI: 10.1016/j.mrfmmm.2009.09.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Revised: 08/31/2009] [Accepted: 09/16/2009] [Indexed: 10/20/2022]
Abstract
Poly(ADP-ribose) polymerase-1 (PARP-1) is a base excision repair (BER) protein that binds to DNA single strand breaks (SSBs) and subsequently synthesizes and transfers poly(ADP-ribose) polymers to various nuclear proteins. Numerous biochemical studies have implicated PARP-1 as a modulator of BER; however, the role of PARP-1 in BER in living cells remains unclear partly due to lack of accurate quantitation of BER intermediates existing in cells. Since DT40 cells, chicken B lymphocytes, naturally lack PARP-2, DT40 cells allow for the investigation of the PARP-1 null phenotype without confounding by PARP-2. To test the hypothesis that PARP-1 is necessary for efficient BER during methylmethane sulfonate (MMS) exposure in vertebrate cells, intact DT40 cells and their isogenic PARP-1 null counterparts were challenged with different exposure scenarios for phenotypic characterization. With chronic exposure, PARP-1 null cells exhibited sensitivity to MMS but with an acute exposure did not accumulate base lesions or AP sites to a greater extent than wild-type cells. However, an increase in SSB content in PARP-1 null cell DNA, as indicated by glyoxal gel electrophoresis under neutral conditions, suggested the presence of BER intermediates. These data suggest that during exposure, PARP-1 impacts the stage of BER after excision of the deoxyribosephosphate moiety from the 5' end of DNA strand breaks by polymerase beta.
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Affiliation(s)
- Brian F Pachkowski
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC, USA
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Tano K, Ichikawa Y, Kinoshita H. [Use of multidetector-row computed tomography in a patient with completely obstructed left anterior descending artery]. Kyobu Geka 2009; 62:802-806. [PMID: 19670783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Multidetector-row computed tomography (MDCT) is a useful diagnostic procedure prior to coronary artery bypass grafting (CABG) as it visualizes the coronary artery less invasively, with higher negative predictive value and lower cost compared with standard coronary angiography (CAG). We recently experienced a case in which the left anterior descending artery (LAD) occlusion prevented CAG evaluation of peripheral vascular status and percutaneous coronary intervention (PCI) or CABG could not be indicated by CAG, whereas MDCT demonstrated a patency of the peripheral LAD. An off-pump coronary artery bypass surgery was performed based on the MDCT findings, and the intraoperative findings were essentially consistent with the MDCT findings. Our experience in this case suggests that the indication for CABG may be accurately judged by using high-resolution MDCT in cases in which CABG graftability may not be judged by CAG.
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Affiliation(s)
- K Tano
- Department of Cardiovascular Surgery, Japanese Red Cross Kochi Hospital, Kochi, Japan
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Masunaga SI, Kono K, Nakamura J, Tano K, Yoshida H, Watanabe M, Kashino G, Suzuki M, Kinashi Y, Liu Y, Ono K. Usefulness of hexamethylenetetramine in combination with chemotherapy using free and pegylated liposomal doxorubicin in vivo, referring to the effect on quiescent cells. Oncol Rep 2009; 21:1307-12. [PMID: 19360308 DOI: 10.3892/or_00000355] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
SCC VII tumor-bearing mice were continuously given 5-bromo-2'-deoxyuridine (BrdU) to label all intratumor proliferating (P) cells. They received hexamethylenetetramine (HMTA) either once intraperitoneally or continuously subcutaneously together with chemotherapy using intraperitoneally administered free doxorubicin (DXR) or intravenously injected pegylated liposomal doxorubicin (PLD). One hour after the free DXR loading or 24 h after the PLD loading, the response of intratumor quiescent (Q) cells was assessed in terms of the micronucleus frequency using immunofluorescence staining for BrdU. The response of the total (P + Q) tumor cell population was determined from the tumors not treated with BrdU. Encapsulation of DXR into pegylated liposomes significantly enhanced cytotoxicity, especially in Q cells. HMTA, especially when administered continuously, efficiently increased the sensitivity to DXR, particularly in Q cells. The increase in sensitivity on the continuous rather than single administration of HMTA was a little clearer in the total cell population than in Q cells. DXR's encapsulation into pegylated liposomes and combination with HMTA, particularly when administered continuously, apparently reduced the difference in sensitivity to free DXR between the total and Q cell populations. In terms of the tumor cell-killing effect as a whole, including Q cells, the encapsulation of DXR into pegylated liposomes and combination with HMTA, particularly through continuous administration, are very promising, taking into account that HMTA has been used clinically.
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Affiliation(s)
- Shin-Ichiro Masunaga
- Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, Osaka 590-0494, Japan.
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Takada S, Inoue E, Tano K, Yoshii H, Abe T, Yoshimura A, Akita M, Tada S, Watanabe M, Seki M, Enomoto T. Generation and characterization of cells that can be conditionally depleted of mitochondrial SOD2. Biochem Biophys Res Commun 2008; 379:233-8. [PMID: 19100713 DOI: 10.1016/j.bbrc.2008.12.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Accepted: 12/09/2008] [Indexed: 01/01/2023]
Abstract
Manganese-dependent superoxide dismutase (SOD2) serves as the primary defense against mitochondrial superoxide, and decreased SOD2 activity results in a range of pathologies. To investigate the events occurring soon after depletion of SOD2, we generated SOD2 gene knockout chicken DT40 cells complemented with a human SOD2 (hSOD2) cDNA, whose expression can be switched off by doxycycline (Dox). When SOD2 was depleted by the addition of Dox, the cells grew slightly slower and formed fewer colonies than cells expressing hSOD2. In addition, these cells showed a high sensitivity to paraquat, which produces superoxide, and died through apoptosis. In contrast to results obtained with mouse and DrosophilaSod2 mutants, we found no indication of an increase in DNA lesions due to depletion of SOD2.
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Affiliation(s)
- Shunya Takada
- Molecular Cell Biology Laboratory, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
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Tano K, Nagata M, Akimitsu N. S-II mediated gene regulation. Drug Discov Ther 2008; 2:136-139. [PMID: 22504566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
S-II, also designated as TFIIS, was the first identified transcription elongation factor and is widely found in eukaryotes. Among known elongation factors, S-II has a characteristic biochemical activity: it facilitates the elongation process by allowing RNA polymerase II (RNAPII) to read through transcriptional blocks in vitro. While the biochemical and molecular mechanism of stimulating elongation in vitro has been shown in detail, the in vivo role of S-II long remained unclear. Recent research has revealed that S-II has a crucial role in the activation of expression of a set of genes in vivo. In this review, we summarize recent studies focusing on the regulation of gene expression by S-II and discuss the biological functions of S-II.
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Affiliation(s)
- K Tano
- Radioisotope Center, the University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
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Ridpath JR, Nakamura A, Tano K, Luke AM, Sonoda E, Arakawa H, Buerstedde JM, Gillespie DA, Sale JE, Yamazoe M, Bishop DK, Takata M, Takeda S, Watanabe M, Swenberg JA, Nakamura J. Cells Deficient in the FANC/BRCA Pathway Are Hypersensitive to Plasma Levels of Formaldehyde. Cancer Res 2007; 67:11117-22. [DOI: 10.1158/0008-5472.can-07-3028] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Yoshimura M, Kohzaki M, Nakamura J, Asagoshi K, Sonoda E, Hou E, Prasad R, Wilson SH, Tano K, Yasui A, Lan L, Seki M, Wood RD, Arakawa H, Buerstedde JM, Hochegger H, Okada T, Hiraoka M, Takeda S. Vertebrate POLQ and POLbeta cooperate in base excision repair of oxidative DNA damage. Mol Cell 2006; 24:115-25. [PMID: 17018297 PMCID: PMC1868411 DOI: 10.1016/j.molcel.2006.07.032] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2006] [Revised: 07/02/2006] [Accepted: 07/28/2006] [Indexed: 01/01/2023]
Abstract
Base excision repair (BER) plays an essential role in protecting cells from mutagenic base damage caused by oxidative stress, hydrolysis, and environmental factors. POLQ is a DNA polymerase, which appears to be involved in translesion DNA synthesis (TLS) past base damage. We disrupted POLQ, and its homologs HEL308 and POLN in chicken DT40 cells, and also created polq/hel308 and polq/poln double mutants. We found that POLQ-deficient mutants exhibit hypersensitivity to oxidative base damage induced by H(2)O(2), but not to UV or cisplatin. Surprisingly, this phenotype was synergistically increased by concomitant deletion of the major BER polymerase, POLbeta. Moreover, extracts from a polq null mutant cell line show reduced BER activity, and POLQ, like POLbeta, accumulated rapidly at sites of base damage. Accordingly, POLQ and POLbeta share an overlapping function in the repair of oxidative base damage. Taken together, these results suggest a role for vertebrate POLQ in BER.
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Affiliation(s)
- Michio Yoshimura
- Department of Radiation Genetics, CREST, Japan Science and Technology Laboratory, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawaharacho, Sakyo-ku, Kyoto 606-8507
| | - Masaoki Kohzaki
- Department of Radiation Genetics, CREST, Japan Science and Technology Laboratory, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501
- Research Reactor Institute, Kyoto University, 2 Asashironishi, Kumatoricho, Sennan-gun, Osaka 590-0494, Japan
| | - Jun Nakamura
- Department of Environmental Sciences and Engineering, The University of North Carolina, Chapel Hill, North Carolina 27599
| | - Kenjiro Asagoshi
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709
| | - Eiichiro Sonoda
- Department of Radiation Genetics, CREST, Japan Science and Technology Laboratory, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501
| | - Esther Hou
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709
| | - Rajendra Prasad
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709
| | - Samuel H. Wilson
- Laboratory of Structural Biology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709
| | - Keizo Tano
- Research Reactor Institute, Kyoto University, 2 Asashironishi, Kumatoricho, Sennan-gun, Osaka 590-0494, Japan
| | - Akira Yasui
- Department of Molecular Genetics, Institute of Development, Aging, and Cancer, Tohoku University, Seiryomachi 4-1, Sendai 980-8575, Japan
| | - Li Lan
- Department of Molecular Genetics, Institute of Development, Aging, and Cancer, Tohoku University, Seiryomachi 4-1, Sendai 980-8575, Japan
| | - Mineaki Seki
- University of Pittsburgh, Hillman Cancer Center, 5117 Centre Avenue, Research Pavilion Suite 2.6, Pittsburgh, Pennsylvania 15213
| | - Richard D. Wood
- University of Pittsburgh, Hillman Cancer Center, 5117 Centre Avenue, Research Pavilion Suite 2.6, Pittsburgh, Pennsylvania 15213
| | - Hiroshi Arakawa
- Institute of Molecular Radiobiology, GSF, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Munich, Germany
| | - Jean-Marie Buerstedde
- Institute of Molecular Radiobiology, GSF, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Munich, Germany
| | - Helfrid Hochegger
- Department of Radiation Genetics, CREST, Japan Science and Technology Laboratory, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501
| | - Takashi Okada
- Department of Radiation Genetics, CREST, Japan Science and Technology Laboratory, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501
- Department of Urology, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawaharacho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Masahiro Hiraoka
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawaharacho, Sakyo-ku, Kyoto 606-8507
| | - Shunichi Takeda
- Department of Radiation Genetics, CREST, Japan Science and Technology Laboratory, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501
- *Correspondence:
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Doi T, Yonekura SI, Tano K, Yasuhira S, Yonei S, Zhang QM. The Shizosaccharomyces pombe homolog (SpMYH) of the Escherichia coli MutY is required for removal of guanine from 8-oxoguanine/guanine mispairs to prevent G:C to C:G transversions. J Radiat Res 2005; 46:205-14. [PMID: 15988139 DOI: 10.1269/jrr.46.205] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The frequency of G:C-->C:G transversions significantly increases upon exposure of cells to ionizing radiation or reactive oxygen species. Transversions can be prevented by base excision repair, which removes the causative modified bases from DNA. Our previous studies revealed that MutY is responsible for removing guanine from 7,8-dihydro-8-oxoguanine/guanine mispairs (8-oxoG/G) and prevents the generation of G:C-->C:G transversions in E. coli. SpMYH, a homolog of E. coli MutY, had been identified and characterized in the fission yeast S. pombe. Purified SpMYH has adenine DNA glycosylase activity on A/8-oxoG and A/G mismatch-containing oligonucleotides. In this study, we examined whether SpMYH has a similar activity allowing it to remove G from 8-oxoG/G in DNA. The purified SpMYH tightly bound to duplex oligonucleotides containing 8-oxoG/G and removed the unmodified G from 8-oxoG/G as efficiently as A from 8-oxoG/A. The activity was absent in the cell extract prepared from an SpMYH-knockout strain of S. pombe. The expression of SpMYH markedly reduced the frequency of spontaneous G:C-->C:G transversions in the E. coli mutY mutant. These results demonstrate that SpMYH is involved in the repair of 8-oxoG/G, by which it prevents mutations induced by oxidative stress in S. pombe.
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Affiliation(s)
- Takashi Doi
- Laboratory of Radiation Biology, Graduate School of Science, Kyoto University, Japan
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Horike K, Tano K, Kitaichi T, Ogawa Y, Yoshizumi M, Kato I, Hori T, Kitagawa T. [Infant case and adult case of scimitar syndrome with lung sequestration]. Kyobu Geka 2003; 56:851-5. [PMID: 13677921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/23/2023]
Abstract
We present 2 cases of Scimitar syndrome with lung sequestration, 1 of which is infant case and the other is adult. A 3-month-old baby was transferred to our hospital because of severe heart failure. Cardiac ultrasonography and angiography revealed atrial septal defect and lung sequestration. Because of critical condition, she underwent emergency operation. After the operation of abnormal lung resection, her general condition improved. We emphasize that the prognosis is influenced by operation timing. A 20-year-old female was admitted for atrial septal defect. We diagnosed Scimitar syndrome and lung sequestration as the result of close examinations. We carried out definitive operations of the closure of atrial septal defect, the correction of partially anomalous pulmonary venous return and the resection of malformed lung. This adult case is popular one of Scimitar syndrome.
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Affiliation(s)
- K Horike
- Department of Cardiovascular Surgery, Tokushima University School of Medicine, Tokushima, Japan
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Shimada Y, Nishimura M, Kakinuma S, Ogiu T, Fujimoto H, Kubo A, Nagai J, Kobayash K, Tano K, Yoshinaga S, Bhakat KK. Genetic susceptibility to thymic lymphomas and K-ras gene mutation in mice after exposure to X-rays and N-ethyl-N-nitrosourea. Int J Radiat Biol 2003; 79:423-30. [PMID: 12963544 DOI: 10.1080/0955300031000139371] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE Ras activation is one of the major mechanisms for the development of murine thymic lymphomas by radiation and chemical carcinogens. To gain insight into the relationship between genetic susceptibility and ras gene mutation, the frequency and spectrum of ras gene mutation was examined in thymic lymphomas from susceptible and resistant mice. MATERIALS AND METHODS K- and N-ras mutations in thymic lymphomas that arose in X-ray-irradiated and N-ethyl-N-nitrosourea (ENU)-treated mice of susceptible C57BL/6, rather resistant C3H and their hybrid B6C3F1 were analysed by polymerase chain reaction-single-strand conformation polymorphism and subsequent DNA sequencing. RESULTS C57BL/6 exhibited a higher incidence of thymic lymphomas after exposure to X-rays and ENU than C3H, with B6C3F1 being intermediate. K-ras gene mutations occurred frequently in the pathogenesis of ENU-induced thymic lymphomas in susceptible C57BL/6 as opposed to resistant C3H. The ras mutations were more frequent in ENU-induced thymic lymphomas than X-ray-induced thymic lymphomas, and with the latter, there was no clear evidence for strain differences, suggesting that the genetic susceptibility to X-rays was independent of ras activation. The mutations of K-ras in thymic lymphomas from C57BL/6 were predominantly GGT to GAT in codon 12, whereas this mutation type was never found in those from C3H. No strain difference was observed in the nucleotide sequence or expression levels of O(6)-alkylguanine alkyltransferase, indicating that this enzyme did not account for the genetic susceptibility to ras activation. CONCLUSIONS The results indicate that there is a clear strain and carcinogen dependency of K-ras mutation and that the frequency of ras mutation might determine the genetic susceptibility to ENU-induced lymphomagenesis, whereas pathways independent of ras activation might determine the susceptibility to X-ray-induced lymphomagenesis.
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Affiliation(s)
- Y Shimada
- Low Dose Radiation Effect Project, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan.
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Tano K, Iwamatsu Y, Yasuhira S, Utsumi H, Takimoto K. Increased base change mutations at G:C pairs in Escherichia coli deficient in endonuclease III and VIII. J Radiat Res 2001; 42:409-413. [PMID: 11951664 DOI: 10.1269/jrr.42.409] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Various types of mutation induced by oxidative DNA damage, induced by hydrogen peroxide and riboflavin photosensitization, were determined in Escherichia coli (E. coli) mutants deficient in endonuclease III (endo III) and endonuclease VIII (endo VIII). The majority of hydrogen peroxide-induced and spontaneous mutations consisted of G:C to A:T and to T:A base changes, shown on the mutation assay system by a reversion at a specific site of the lacZ gene. Base changes were also localized at G:C pairs in the mutation of the supF gene, induced by riboflavin photosensitization, which specifically yields 7,8-dihydro-8-oxoguanine (8-oxoG). G:C to T:A and to C:G transversions dominated in both mutants. These results suggest that endo III and endo VIII are involved in the repair of oxidative lesions of guanine.
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Affiliation(s)
- K Tano
- Research Reactor Institute, Kyoto University, Noda, Kumatori, Sennan-gun, Osaka 590-0454, Japan.
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50
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Tano L, Tano K, Hellström S. [Check ups after acute otitis media should be revised. What are we looking for and why?]. Lakartidningen 2001; 98:4997-9. [PMID: 11816903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The latest Swedish consensus conference (May 2000) on treatment of acute otitis media (AOM) states that a check-up should be made three months after an episode of AOM. In order to find out how these recommendations are implemented 36 general practitioners were asked about their management of AOM check-ups. Almost all GPs checked children below 5 years of age by otoscopy but only 66 percent checked the mobility of the tympanic membrane. The follow-up procedure varied considerably. In a study of 129 ears (99 children) three months after an episode of AOM the diagnostic accuracy of pneumatic otoscopy, tympanometry and audiometry performed at a health care center was studied. The tympanometry performed by a nursing assistant had a very high sensitivity (93 percent) regarding secretory otitis media and could be used as a check-up after AOM. Thus there seems to be no need for the GP to examine ears where tympanometry is normal, but concentrate on the cases with pathologic tympanometry.
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