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Morita K, Nishimura Y, Nakamura S, Arai Y, Numako C, Sato K, Nakayama M, Akasaka H, Sasaki R, Ogino C, Kondo A. Titanium oxide nano-radiosensitizers for hydrogen peroxide delivery into cancer cells. Colloids Surf B Biointerfaces 2020; 198:111451. [PMID: 33223346 DOI: 10.1016/j.colsurfb.2020.111451] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 10/16/2020] [Accepted: 11/03/2020] [Indexed: 11/18/2022]
Abstract
Polyacrylic acid-modified titanium peroxide nanoparticles (PAA-TiOx NPs) are promising radiosensitizers that enhance the therapeutic effect of X-ray irradiation after local injection into tumors. However, the mechanism for this reaction has remained unclear with the exception of the involvement of hydrogen peroxide (H2O2), which is released by PAA-TiOx NPs to a liquid phase during dispersion. In the present study, a clonogenic assay was used to compare PAA-TiOx NPs with free H2O2 molecules to investigate the effect exerted on the radiosensitivity of cancer cells in vitro. A cell-free dialysis method revealed that a portion of the H2O2 adsorbed onto the PAA-TiOx NPs during synthesis could be released during a treatment regimen. The H2O2 release lasted for 7 h, which was sufficient for one radiation treatment procedure. For in vitro experiments, cultured human pancreatic cancer cells took up PAA-TiOx NPs in 10 min after administration. Interestingly, when the cells were washed with a buffer after treatment with either a PAA-TiOx NP or H2O2 solution, the intracellular H2O2 levels remained higher with PAA-TiOx NP treatment compared with the H2O2 solution treatment. Furthermore, the effects of subsequent X-ray irradiation corresponded to the intracellular H2O2 levels. These results indicate that PAA-TiOx NPs are efficient carriers of H2O2 into cancer cells and thus enhance the radiosensitivity.
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Affiliation(s)
- Kenta Morita
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Rokkodaicho 1-1, Nada-ku, Kobe 657-8501, Japan; Research Facility Center for Science and Technology, Kobe University, Rokkodaicho 1-1, Nada-ku, Kobe 657-8501, Japan
| | - Yuya Nishimura
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Rokkodaicho 1-1, Nada-ku, Kobe 657-8501, Japan
| | - Satoko Nakamura
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Rokkodaicho 1-1, Nada-ku, Kobe 657-8501, Japan
| | - Yuki Arai
- Graduate School of Science, Chiba University, 1-33, Yayoi, Inage, Chiba, 263-8522, Japan
| | - Chiya Numako
- Graduate School of Science, Chiba University, 1-33, Yayoi, Inage, Chiba, 263-8522, Japan
| | - Kazuyoshi Sato
- Division of Environmental Engineering Science, Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjincho, Kiryu, Gunma, 376-8515, Japan
| | - Masao Nakayama
- Division of Radiation Oncology, Kobe University Graduate School of Medicine, Kusunokicho 7-5-2, Chuou-ku, Kobe 650-0017, Japan
| | - Hiroaki Akasaka
- Division of Radiation Oncology, Kobe University Graduate School of Medicine, Kusunokicho 7-5-2, Chuou-ku, Kobe 650-0017, Japan
| | - Ryohei Sasaki
- Division of Radiation Oncology, Kobe University Graduate School of Medicine, Kusunokicho 7-5-2, Chuou-ku, Kobe 650-0017, Japan
| | - Chiaki Ogino
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Rokkodaicho 1-1, Nada-ku, Kobe 657-8501, Japan.
| | - Akihiko Kondo
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Rokkodaicho 1-1, Nada-ku, Kobe 657-8501, Japan; Organization of Advanced Science and Technology, Kobe University, Rokkodaicho 1-1, Nada-ku, Kobe 657-8501, Japan
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Mitsuhashi Y, Furusawa Y, Aradate T, Zhao QL, Moniruzzaman R, Kanamori M, Noguchi K, Kondo T. 3-O-trans-p-coumaroyl-alphitolic acid, a triterpenoid from Zizyphus jujuba, leads to apoptotic cell death in human leukemia cells through reactive oxygen species production and activation of the unfolded protein response. PLoS One 2017; 12:e0183712. [PMID: 28832644 PMCID: PMC5568338 DOI: 10.1371/journal.pone.0183712] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 08/09/2017] [Indexed: 11/23/2022] Open
Abstract
3-O-trans-p-coumaroyl-alphitolic acid (3OTPCA), a triterpenoid isolated from the plant Zizyphus jujuba (ZJ), is known to be cytotoxic to cancer cells; however, the molecular mechanism underlying 3OTPCA-induced cell death remains unknown. Here, we provide novel evidence that 3OTPCA induces apoptotic cell death in human leukemia cells. We found that 3OPTCA induces DNA fragmentation within 24 h after treatment in U937 cells, which was also observed in other leukemia cell lines, including Molt-4 and Jurkat cells. We then investigated other parameters involved in apoptosis, including phosphatidylserine externalization and caspase-3 cleavage in U937 cells treated with 3OTPCA. 3OTPCA caused significant DNA fragmentation, annexin-V binding, and caspase-3 cleavage, indicating that 3OTPCA exerts cytotoxicity through apoptosis induction. RNA-seq analysis revealed that the expression of transcripts associated with the unfolded protein response (UPR), such as spliced XBP-1 and CHOP, were up-regulated by 3OTPCA treatment. 3OTPCA-induced UPR activation may be due to endoplasmic reticulum (ER) stress because both 3OTPCA and thapsigargin, an endoplasmic Ca2+ transport ATPase inhibitor, increased intracellular calcium levels. 3OTPCA down-regulated the expression of Bcl-2, a target of CHOP, and led to the loss of the mitochondrial membrane, indicating that the intrinsic (mitochondrial) apoptotic pathway was triggered by 3OTPCA, likely through UPR activation. Furthermore, we found that 3OTPCA induced superoxide anion generation and, following p38 MAPK phosphorylation, caspase-8 cleavage without affecting Fas expression. It also induced subsequent Bid cleavage, which may enhance the apoptosis triggered by the intrinsic pathway. These findings reveal for the first time that 3OTPCA induces apoptotic cell death through the generation of reactive oxygen species and activation of UPR.
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Affiliation(s)
- Yohei Mitsuhashi
- Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
| | - Yukihiro Furusawa
- Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
- Department of Liberal Arts and Sciences, Toyama Prefectural University, Kurokawa, Toyama, Japan
- * E-mail:
| | - Tadashi Aradate
- Department of Medical Biology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
| | - Qing-Li Zhao
- Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
| | - Rohan Moniruzzaman
- Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
| | - Masahiko Kanamori
- Department of Human Science 1, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
| | - Kyo Noguchi
- Department of Radiology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
| | - Takashi Kondo
- Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
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Rehman MU, Jawaid P, Zhao QL, Li P, Narita K, Katoh T, Shimizu T, Kondo T. Low-dose spiruchostatin-B, a potent histone deacetylase inhibitor enhances radiation-induced apoptosis in human lymphoma U937 cells via modulation of redox signaling. Free Radic Res 2016; 50:596-610. [PMID: 27108737 DOI: 10.3109/10715762.2015.1115029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Spiruchostatin B (SP-B), is a potent histone deacetylase (HDAC) inhibitor, in addition to HDAC inhibition, the pharmacological effects of SP-B are also attributed to its ability to produce intracellular reactive oxygen species (ROS), particularly H2O2. In this study, we investigated the effects of low dose (non-toxic) SP-B on radiation-induced apoptosis in human lymphoma U937 cells in vitro. The treatment of cells with low-dose SP-B induced the acetylation of histones, however, does not induce apoptosis. Whereas, the combined treatment with SP-B and radiation significantly enhanced the radiation-induced apoptosis, suggesting the potential role of this combined treatment for future radiation therapy. Interestingly, the enhancement of apoptosis was accompanied by significant increased in the ROS generation. Pre-treatment with an antioxidant, N-acetyl-l-cysteine (NAC) significantly inhibited the enhancement of apoptosis induced by combined treatment, indicating that ROS play an essential role. It was also found that SP-B combined with radiation caused the activation of death receptor and intrinsic apoptotic pathways, via modulation of ROS-mediated signaling. Moreover, SP-B also significantly enhanced the radiation-induced apoptosis in other lymphoma cell lines such as Molt-4 and HL-60. Taken together, our findings suggest that the low-dose SP-B enhances radiation-induced apoptosis via modulation of redox signaling because of its ability to serve as an intracellular ROS generating agent, mainly (H2O2 or [Formula: see text]). This study provides further insights into the mechanism of action of SP-B with radiation and demonstrates that SP-B can be used as a future novel sensitizer for radiation therapy.
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Affiliation(s)
- Mati Ur Rehman
- a Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama , Toyama , Japan
| | - Paras Jawaid
- a Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama , Toyama , Japan
| | - Qing Li Zhao
- a Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama , Toyama , Japan
| | - Peng Li
- a Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama , Toyama , Japan
| | - Koichi Narita
- b Laboratory of Synthetic and Medicinal Chemistry, Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University , Aoba-ku, Sendai , Japan
| | - Tadashi Katoh
- b Laboratory of Synthetic and Medicinal Chemistry, Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University , Aoba-ku, Sendai , Japan
| | - Tadamichi Shimizu
- c Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama , Toyama , Japan
| | - Takashi Kondo
- a Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama , Toyama , Japan
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Radiation enhancing effects of sanazole and gemcitabine in hypoxic breast and cervical cancer cells in vitro. Contemp Oncol (Pozn) 2015; 19:236-40. [PMID: 26557765 PMCID: PMC4631282 DOI: 10.5114/wo.2015.51820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 04/15/2014] [Accepted: 05/29/2014] [Indexed: 11/17/2022] Open
Abstract
AIM OF THE STUDY Sanazole and gemcitabine have been proven clinically as hypoxic cell radiosensitisers. This study was conducted to determine the radiation enhancing effects of sanazole and gemcitabine when administered together at relevant concentrations into hypoxic human MCF-7 and HeLa cells. MATERIAL AND METHODS A 3-(4,5 dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay was used to evaluate the number of surviving cells. Cell cycle was determined by flow cytometry. Cell surviving fractions were determined by the standard in vitro colony formation assay. RESULTS The cell colony formation assay indicated that the radiosensitivity of hypoxic MCF-7 and HeLa cells was enhanced by sanazole or gemcitabine. The combination of the two drugs displayed significant radiation enhancing effects at the irradiation doses of 6, 8, and 10 Gy in both cell lines, which were arrested in the S phase. CONCLUSIONS This study indicated that the co-administration of the two drugs may result in a beneficial gain in radio-therapy for hypoxic breast cancer and cervical cancer.
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Jawaid P, Rehman MU, Yoshihisa Y, Li P, Zhao QL, Hassan MA, Miyamoto Y, Shimizu T, Kondo T. Effects of SOD/catalase mimetic platinum nanoparticles on radiation-induced apoptosis in human lymphoma U937 cells. Apoptosis 2014; 19:1006-16. [PMID: 24687228 DOI: 10.1007/s10495-014-0972-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Since polyacrylic acid capped platinum nano-particles (nano-Pts) are known to have a unique ability to quench superoxide (O2(-)) and hydrogen peroxide (H2O2), the anti-oxidant activity of nano-Pts against apoptosis induced by x-irradiation in human lymphoma U937 cells was investigated. DNA fragmentation assay, Annexin V-FITC/PI by flow cytometry and Giemsa staining revealed a significant decrease in apoptosis induced by 10 Gy, when cells were pre-treated with nano-Pts in a dose-dependent manner. Pre-treatment with nano-Pts significantly decreased radiation-induced reactive oxygen species (ROS) production, Fas expression and loss of mitochondrial membrane potential as determined by flow-cytometry. Furthermore, western blot analysis also showed that the expression of cleaved caspase-3, Bid and cytosolic cytochrome-c were significantly reduced in nano-Pts pretreated cells. Due to the catalase mimetic activity of nano-Pts, these results indicate that pre-treatment of U937 cells with nano-Pts significantly protect radiation-induced apoptosis by inhibiting intracellular ROS (mainly H2O2), which plays a key role in the induction of apoptosis, because of no practical observation of intracellular O2(-) formation.
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Affiliation(s)
- Paras Jawaid
- Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences University of Toyama, Toyama, Japan
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Chandna S, Suman S, Chandna M, Pandey A, Singh V, Kumar A, Dwarakanath BS, Seth RK. Radioresistant Sf9 insect cells undergo an atypical form of Bax-dependent apoptosis at very high doses of γ-radiation. Int J Radiat Biol 2013; 89:1017-27. [PMID: 23859363 DOI: 10.3109/09553002.2013.825059] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
PURPOSE To investigate the underlying mechanisms of cell-death at extremely high doses of radiation in radioresistant Spodoptera frugiperda-9 (Sf9) insect cells. MATERIALS AND METHODS Morphology, cell proliferation and DNA-fragmentation analysis was performed at 500-2000 Gy. Changes in intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP), cardiolipin oxidation and Annexin-V externalization were studied using flow-cytometry. Cytochrome-c release was measured using immunofluorescence microscopy. Inhibitors of apoptosis, i.e., Bongkrekic acid (BKA), Caspase-9 inhibitor (C9i), 5-(4-fluorosulfonylbenzoyl) adenosine hydrochloride (FSBA) and Cyclosporin-A (CsA) were used to dissect apoptotic mechanism at many classical steps. Caspase-3 activity was measured using a caspase-activity assay kit. RESULTS A dose-dependent induction of typical apoptosis was observed at extremely high doses, marked by extensive apoptotic body formation. However, certain atypical responses such as cellular hypertrophy and the lack of phosphatidylserine-externalization were observed during the initial hours after radiation. Loss of mitochondrial membrane potential observed at 48 h following a 2000 Gy dose was accompanied by an increase in ROS that caused significant cardiolipin oxidation leading to cytochrome-c release, caspase activation and internucleosomal DNA fragmentation. Inhibitors of B-cell lymphoma-2 (Bcl-2)-associated X protein (Bax)-mediated cytochrome-c release, apoptosome formation and caspase-9 effectively prevented radiation-induced apoptosis, strongly suggesting the role of Bax-dependent cell death mechanism. CONCLUSIONS Our study demonstrates that the Sf9 insect cells display good homology with human cells in the mitochondria-dependent events during radiation-induced apoptosis, although doses eliciting similar responses were 50-200 times higher than human cells. Factors upstream to mitochondrial damage remain pertinent for a thorough understanding of this extreme radioresistance displayed by lepidopteran cells.
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Affiliation(s)
- Sudhir Chandna
- Natural Radiation Response Mechanisms Group, Division of Radiation Biosciences, Institute of Nuclear Medicine and Allied Sciences , Delhi
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Evaluation of alkylmaltosides as intestinal permeation enhancers: Comparison between rat intestinal mucosal sheets and Caco-2 monolayers. Eur J Pharm Sci 2012; 47:701-12. [DOI: 10.1016/j.ejps.2012.08.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2012] [Revised: 08/08/2012] [Accepted: 08/08/2012] [Indexed: 01/10/2023]
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Molecular mechanisms of apoptosis induction by 2-dodecylcyclobutanone, a radiolytic product of palmitic acid, in human lymphoma U937 cells. Apoptosis 2012; 17:636-45. [PMID: 22311471 DOI: 10.1007/s10495-012-0698-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The irradiation of fat-containing food forms 2-dodecylcyclobutanone (2-DCB) from palmitic acid (PA). In this study, we investigated whether 2-DCB and PA induce apoptosis in human lymphoma U937 cells. We found that cell viability decreased by 2-DCB and apoptosis was induced by 2-DCB and PA. 2-DCB and PA significantly enhanced the formation of intracellular reactive oxygen species (ROS). Apoptosis induced by 2-DCB and PA was strongly prevented by an antioxidant, N-acetyl-L: -cysteine. The treatment with 2-DCB and PA resulted in the loss of mitochondrial membrane potential, and Fas, caspase-8 and caspase-3 activation. Pretreatment with a pan-caspase inhibitor (z-VAD) significantly inhibited apoptosis induced by 2-DCB and PA. Moreover, 2-DCB and PA also induced Bax up-regulation, the reduction in Bcl-2 expression level, Bid cleavage and the release of cytochrome c from the mitochondria to the cytosol. In addition, an increase in intracellular Ca(2+) concentration ([Ca(2+)](i)) was observed after the treatment with 2-DCB and PA. Our results indicated that intracellular ROS generation, the modulation of the Fas-mitochondrion-caspase-dependent pathway and the increase in [Ca(2+)](i) involved in apoptosis are induced by 2-DCB and PA in U937 cells.
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Furusawa Y, Iizumi T, Fujiwara Y, Zhao QL, Tabuchi Y, Nomura T, Kondo T. Inhibition of checkpoint kinase 1 abrogates G2/M checkpoint activation and promotes apoptosis under heat stress. Apoptosis 2012; 17:102-12. [PMID: 22080164 DOI: 10.1007/s10495-011-0660-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Hyperthermia induced by heat stress (HS) inhibits the proliferation of cancer cells and induces their apoptosis. However, the mechanism underlying HS-induced apoptosis remains elusive. Here, we demonstrated a novel evidence that checkpoint kinase 1 (Chk1) plays crucial roles in the apoptosis and regulation of cell cycle progression in cells under HS. In human leukemia Jurkat cells, interestingly, the ataxia telangiectasia and Rad-3 related (ATR)-Chk1 pathway was preferentially activated rather than the ataxia telangiectasia mutated (ATM)-checkpoint kinase 2 (Chk2) pathway under HS. The selective inhibitors of ATR or Chk1 abrogated HS-induced apoptosis in human leukemia Jurkat cells whereas the inhibition of ATM or Chk2 caused only marginal effects. Inhibition of ATR and Chk1 also abrogated G2/M checkpoint activation by HS in Jurkat cells. The effects of small interfering RNA targeting Chk1 were similar to those of the selective inhibitor of Chk1. In addition, the efficiencies of Chk1 inhibition on G2/M checkpoint abrogation and apoptosis induction were confirmed in the adherent cancer cell lines HeLa, HSC3, and PC3, suggesting that the targeting of Chk1 can be effective in solid tumors cells. In conclusion, these findings indicate a novel molecular basis of G2/M checkpoint activation and apoptosis in cells exposed to HS.
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Affiliation(s)
- Yukihiro Furusawa
- Department of Radiological Sciences, Life Science Research Center, Graduate School of Medicine Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan
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Differential cytotoxicity and sonosensitization by sanazole: effect of cell type and acoustic parameters. J Med Ultrason (2001) 2011; 38:65-72. [DOI: 10.1007/s10396-010-0295-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Accepted: 11/05/2010] [Indexed: 01/23/2023]
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High Efficacy of Preoperative Low-Dose Radiotherapy with Sanazole (AK-2123) for Extraskeletal Ewing's Sarcoma: A Case Report. Sarcoma 2010; 2011. [PMID: 20871855 PMCID: PMC2943094 DOI: 10.1155/2011/185465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Accepted: 08/20/2010] [Indexed: 11/17/2022] Open
Abstract
Extraskeletal Ewing's sarcoma is a rare soft tissue tumor that is morphologically indistinguishable from Ewing's sarcoma of bone. We report a case of extraskeletal Ewing's sarcoma with several systemic problems. A 69-year-old man presented with a 5-month history of a rapidly enlarging mass in the right thigh. Because preoperative radiotherapy with sanazole (AK-2123) contributed the tumor mass reduction down to 40% in size, the tumor was successfully resected with clear surgical margins and repaired with a musculocutaneous flap. The high efficacy of pre-operative low-dose radiotherapy with sanazole was histologically confirmed that the resected tumor specimen involved no viable tumor cells and showed 100% necrosis. Based on clinical outcomes in this case, the combined modality of pre-operative low-dose radiotherapy with hypoxic cell radiosensitizer and adequate surgical resection might provide for the useful clinical application of extraskeletal Ewing's sarcoma treatment.
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