16 results on '"Itashiki, Y."'
Search Results
2. In-vessel components for initial operation of JT-60SA
- Author
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Takechi, M., Tsuru, D., Fukumoto, M., Sasajima, T., Matsunaga, G., Nakamura, S., Yamamoto, S., Itashiki, Y., Hayashi, T., and Isayama, A.
- Published
- 2021
- Full Text
- View/download PDF
3. Distributions of neutron yields and doses around a water phantom bombarded with 290-MeV/nucleon and 430-MeV/nucleon carbon ions
- Author
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Satoh, D., Kajimoto, T., Shigyo, N., Itashiki, Y., Imabayashi, Y., Koba, Y., Matsufuji, N., Sanami, T., Nakao, N., and Uozumi, Y.
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- 2016
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4. Distributions of neutron yield and dose around a water phantom bombarded by 290-MeV/nucleon and 430-MeV/nucleon carbon ions
- Author
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Satoh, D., Kajimoto, T., Shigyo, N., Itashiki, Y., Imabayashi, Y., Matsufuji, Naruhiro, Sanami, T., Nakao, N., and Uozumi, Y.
- Subjects
Physics::Medical Physics ,Nuclear Theory ,Nuclear Experiment - Abstract
Double-differential neutron yields from a water phantom bombarded by 290-MeV/nucleon and 430-MeV/nucleon carbon ions were measured at production angles of 15°, 30°, 45°, 60°, 75°, and 90°, and angular distributions of neutron yield and dose around the phantom were obtained. The experimental data were compared with the results of the Monte-Carlo simulation code, PHITS. The PHITS results showed a good agreement with the measured data. In addition, we estimated the angular distributions of neutron yield and dose from 0° to 180° including thermal neutrons using PHITS.
- Published
- 2016
5. P7. Efficacy of metronomic chemotherapy with S-1 in human oral squamous cell carcinoma cells
- Author
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Harada, K., primary, Harada, T., additional, Itashiki, Y., additional, Takenawa, T., additional, and Ueyama, Y., additional
- Published
- 2011
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6. P3.47. Effect of S-1 component Gimeracil on DNA double-strand break repair system
- Author
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Harada, K., primary, Itashiki, Y., additional, Takii, M., additional, Suwa, Y., additional, Ueta, Y., additional, and Uchida, K., additional
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- 2009
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7. Effects of different remote ischemia perconditioning methods on cerebral infarct volume and neurological impairment in rats.
- Author
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Otsuka S, Itashiki Y, Tani A, Matsuoka T, Takada S, Matsuzaki R, Nakanishi K, Norimatsu K, Tachibe Y, Kitazato R, Nojima N, Kakimoto S, Kikuchi K, Maruyama I, and Sakakima H
- Subjects
- Rats, Animals, Rats, Sprague-Dawley, Brain-Derived Neurotrophic Factor, Caspase 3, bcl-2-Associated X Protein, Ischemia, Infarction, Cerebral Infarction, Apoptosis, Infarction, Middle Cerebral Artery, Brain Ischemia, Reperfusion Injury pathology
- Abstract
Remote ischemic perconditioning (RIPerC) is a novel neuroprotective method against cerebral infarction that has shown efficacy in animal studies but has not been consistently neuroprotective in clinical trials. We focused on the temporal regulation of ischemia-reperfusion by RIPerC to establish an optimal method for RIPerC. Rats were assigned to four groups: 10 min ischemia, 5 min reperfusion; 10 min ischemia, 10 min reperfusion; 5 min ischemia, 10 min reperfusion; and no RIPerC. RIPerC interventions were performed during ischemic stroke, which was induced by a 60-min left middle cerebral artery occlusion. Infarct volume, sensorimotor function, neurological deficits, and cellular expressions of brain-derived neurotrophic factor (BDNF), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and caspase 3 were evaluated 48 h after the induction of ischemia. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) was also performed. RIPerC of 10 min ischemia/10 min reperfusion, and 5 min ischemia/10 min reperfusion decreased infarct volume, improved sensorimotor function, decreased Bax, caspase 3, and TUNEL-positive cells, and increased BDNF and Bcl-2 expressions. Our findings suggest RIPerC with a reperfusion time of approximately 10 min exerts its neuroprotective effects via an anti-apoptotic mechanism. This study provides important preliminary data to establish more effective RIPerC interventions., (© 2023. The Author(s).)
- Published
- 2023
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8. Antitumor effects of bevacizumab in combination with fluoropyrimidine drugs on human oral squamous cell carcinoma.
- Author
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Itashiki Y, Harada K, Takenawa T, Ferdous T, Ueyama Y, and Mishima K
- Abstract
Vascular endothelial growth factor (VEGF) serves an important role in new blood vessel formation or angiogenesis, which is a critical event in tumor growth and metastasis. Bevacizumab is a humanized monoclonal antibody against VEGF-A, whereas S-1 is a fluoropyrimidine antineoplastic agent that induces apoptosis in various types of cancer cells. The present study evaluated the antitumor effects of bevacizumab in combination with 5-fluorouracil (5-FU) or S-1 against oral squamous cell carcinoma (OSCC) in vitro and in vivo . Two human OSCC cell lines were used, namely the high VEGF-A-expressing HSC-2 cells and the low VEGF-A-expressing SAS cells. MTT assay was used to evaluate the effect of bevacizumab and/or 5-FU against HSC-2 and SAS cell proliferation. Additionally, the antitumor effect of bevacizumab was evaluated alone and in combination with S-1 against HSC-2 tumors in nude mice. S-1 (6.9 mg/kg/day) was administered orally every day for 3 weeks, and bevacizumab (5 ml/kg/day) was injected intraperitoneally twice per week for 3 weeks. Apoptotic cells in mouse tumors were detected using the TUNEL method, and cell proliferation and microvessel density (MVD) were determined by immunohistochemical staining of Ki-67 and CD31, respectively. Bevacizumab alone did not inhibit OSCC cell proliferation in vitro , and did not exhibit any synergistic inhibitory effect in combination with 5-FU in vitro . However, combined bevacizumab and S-1 therapy exerted synergistic and significant antitumor effects in vivo on HSC-2 tumor xenografts, and induced apoptosis in tumor cells. Furthermore, this combination therapy led to decreased MVD and cell proliferative abilities, as well as increased apoptosis in residual tumors. The present findings suggested that the bevacizumab plus S-1 combination therapy may exert antitumor effects in high VEGF-A-expressing OSCC cells., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Itashiki et al.)
- Published
- 2021
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9. Disruption of Midkine gene reduces traumatic brain injury through the modulation of neuroinflammation.
- Author
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Takada S, Sakakima H, Matsuyama T, Otsuka S, Nakanishi K, Norimatsu K, Itashiki Y, Tani A, and Kikuchi K
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- Animals, Apoptosis genetics, Astrocytes pathology, Brain pathology, Calcium-Binding Proteins metabolism, Cell Polarity genetics, Glial Fibrillary Acidic Protein metabolism, Mice, Mice, Inbred C57BL, Mice, Knockout, Microfilament Proteins metabolism, Microglia pathology, RNA, Messenger biosynthesis, RNA, Messenger genetics, Brain Injuries, Traumatic genetics, Brain Injuries, Traumatic pathology, Encephalitis genetics, Encephalitis pathology, Midkine genetics
- Abstract
Background: Midkine (MK) is a multifunctional cytokine found upregulated in the brain in the presence of different disorders characterized by neuroinflammation, including neurodegenerative disorders and ischemia. The neuroinflammatory response to traumatic brain injury (TBI) represents a key secondary injury factor that can result in further neuronal injury. In the present study, we investigated the role of endogenous MK in secondary injury, including neuroinflammation, immune response, and neuronal apoptosis activity, after TBI., Methods: Wild type (Mdk
+/+ ) and MK gene deficient (Mdk-/- ) mice were subjected to fluid percussion injury for TBI models and compared at 3, 7, and 14 days after TBI, in terms of the following: brain tissue loss, neurological deficits, microglia response, astrocytosis, expression of proinflammatory M1 and anti-inflammatory M2 microglia/macrophage phenotype markers, and apoptotic activity., Results: As opposed to Mdk+/+ mice, Mdk-/- mice reported a significantly reduced area of brain tissue loss and an improvement in their neurological deficits. The ratios of the Iba1-immunoreactive microglia/macrophages in the perilesional site were significantly decreased in Mdk-/- than in the Mdk+/+ mice at 3 days after TBI. However, the ratios of the glial fibrillary acidic protein immunoreactive area were similar between the two groups. The M1 phenotype marker (CD16/32) immunoreactive areas were significantly reduced in Mdk-/- than in the Mdk+/+ mice. Likewise, the mRNA levels of the M1 phenotype markers (TNF-α, CD11b) were significantly decreased in Mdk-/- mice than in Mdk+/+ mice. Furthermore, flow cytometry analysis identified the M2 markers, i.e., CD163+ macrophages cells and arginase-1+ microglia cells, to be significantly higher in Mdk-/- than in Mdk+/+ mice. Finally, the ratios of apoptotic neurons were significantly decreased in the area surrounding the lesion in Mdk-/- than in Mdk+/+ mice following TBI., Conclusion: Our findings suggest that MK-deficiency reduced tissue infiltration of microglia/macrophages and altered their polarization status thereby reducing neuroinflammation, neuronal apoptosis, and tissue loss and improving neurological outcomes after TBI. Therefore, targeting MK to modulate neuroinflammation may represent a potential therapeutic strategy for TBI management.- Published
- 2020
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10. Acute changes in cortical activation during active ankle movement after whole-body vibration for spasticity in hemiplegic legs of stroke patients: a functional near-infrared spectroscopy study.
- Author
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Miyara K, Kawamura K, Matsumoto S, Ohwatashi A, Itashiki Y, Uema T, Noma T, Ikeda K, and Shimodozono M
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- Adult, Female, Humans, Male, Middle Aged, Sensorimotor Cortex diagnostic imaging, Ankle physiopathology, Functional Neuroimaging, Hemiplegia etiology, Hemiplegia physiopathology, Hemiplegia therapy, Muscle Spasticity etiology, Muscle Spasticity physiopathology, Muscle Spasticity therapy, Sensorimotor Cortex physiopathology, Spectroscopy, Near-Infrared, Stroke complications, Stroke physiopathology, Stroke therapy, Vibration therapeutic use
- Abstract
Background : A recent study revealed that whole-body vibration (WBV) tends to decrease spasticity in stroke-related hemiplegic legs. However, acute changes in cortical activation after WBV are unclear. Objective : To examine whether WBV induces acute changes in sensorimotor cortical activation in patients with stroke-related hemiplegic legs. Methods : Eleven stroke patients (mean age 52.6 [SD 15.4] years; median time after stroke 3 [25
th and 75th percentiles; 3 and 10.5, respectively] months) participated in a comparative before-and-after intervention trial. Six healthy adults were also studied. WBV at 30 Hz was applied for 5 min to the hamstrings, gastrocnemius, and soleus muscles. Spasticity was assessed according to the modified Ashworth scale (MAS). Active and passive range of motion (A-ROM and P -ROM, respectively) were also measured. Change in Oxy-Hb concentration in bilateral sensorimotor cortex associated with voluntary ankle dorsiflexion of the affected limb was assessed via functional near-infrared spectroscopy (fNIRS) before and immediately after WBV. Results : MAS score, A-ROM, and P -ROM improved immediately after WBV. In the patients, while there was no significant interaction between effects of region (ipsilesional and contralesional sensorimotor cortex) and the WBV intervention (before and immediately after WBV) ( F1,10 = 0.702, p = .422), there was a significant main effect of the WBV intervention ( F1,10 = 6.971, p = .025). In the healthy participants, there was no association with the WBV intervention or region. Conclusions : In patients with stroke-related spastic-hemiplegic legs, WBV might result not only in clinical improvement but also in acute increase in sensorimotor cortical activation.- Published
- 2020
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11. Effects of lentinan alone and in combination with fluoropyrimidine anticancer agent on growth of human oral squamous cell carcinoma in vitro and in vivo.
- Author
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Harada K, Itashiki Y, Takenawa T, and Ueyama Y
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- Animals, Carcinoma, Squamous Cell pathology, Cell Line, Tumor, Drug Combinations, Female, Fluorouracil administration & dosage, Humans, Lentinan administration & dosage, Mice, Mice, Nude, Mouth Neoplasms pathology, Oxonic Acid administration & dosage, Tegafur administration & dosage, Xenograft Model Antitumor Assays, Antineoplastic Combined Chemotherapy Protocols pharmacology, Carcinoma, Squamous Cell drug therapy, Lentinan pharmacology, Mouth Neoplasms drug therapy
- Abstract
Chemotherapy has shown little antitumor activity against advanced oral squamous cell carcinoma (OSCC) patients. Therefore, there is an urgent need to develop more effective therapeutic methods for patients with advanced OSCC. Lentinan, beta-(1-->3)-D-glucan, an extract from the edible mushroom, Lentinus edodes, has been reported to show direct antitumor effects and various immunomodulatory effects. S-1 is an oral antineoplastic agent that can induce apoptosis in various types of cancer cells, including OSCC. Hence, combined treatment of cancer cells with Lentinan and S-1 might exert dramatic antitumor effects on OSCC cells. In this study, the response of human OSCC cells to Lentinan alone and in combination with S-1 was examined using nude mouse xenograft models. S-1 (6.9 mg/kg/day, 7 times/week) was administered orally and Lentinan (0.1 mg/kg/day, 2 times/week) was injected into peritumoral tissue for three weeks. Apoptotic cells were detected by a TUNEL method. The gene expression level of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD) and orotate phosphoribosyl transferase (OPRT) was determined using microdissection and RT-PCR, and their protein levels were determined using ELISA. Combined therapy of Lentinan and S-1 markedly exerted antitumor effects on human OSCC xenografts and significantly induced apoptotic cells in tumors treated with Lentinan plus S-1. Microdissection and RT-PCR revealed that the expression of TS and DPD mRNA was down-regulated and that expression of OPRT mRNA was up-regulated in tumors administered the combined treatment. Moreover, ELISA indicated that the protein levels of TS and DPD were down-regulated, and that OPRT was up-regulated in tumors treated with the combined therapy. During the experimental period, no loss of body weight was observed in mice treated with the combined therapy. These findings demonstrate that the combination of Lentinan and S-1 is effective against OSCC and has the potential of being a new therapeutic tool for future treatment of these tumors.
- Published
- 2010
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12. Cepharanthine inhibits angiogenesis and tumorigenicity of human oral squamous cell carcinoma cells by suppressing expression of vascular endothelial growth factor and interleukin-8.
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Harada K, Ferdous T, Itashiki Y, Takii M, Mano T, Mori Y, and Ueyama Y
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- Animals, Blotting, Western, Carcinoma, Squamous Cell metabolism, Cell Movement drug effects, Cell Proliferation drug effects, Cells, Cultured, Enzyme-Linked Immunosorbent Assay, Female, Humans, Immunohistochemistry, Interleukin-8 biosynthesis, Mice, Mice, Nude, Mouth Neoplasms metabolism, NF-kappa B drug effects, NF-kappa B metabolism, Neovascularization, Pathologic drug therapy, Reverse Transcriptase Polymerase Chain Reaction, Vascular Endothelial Growth Factor A biosynthesis, Xenograft Model Antitumor Assays, Antineoplastic Agents, Phytogenic pharmacology, Benzylisoquinolines pharmacology, Carcinoma, Squamous Cell drug therapy, Interleukin-8 drug effects, Mouth Neoplasms drug therapy, Vascular Endothelial Growth Factor A drug effects
- Abstract
Cepharanthine is a biscoclaurine alkaloid extracted from Stephania cepharantha Hayata, which is widely used for the treatment of many acute and chronic diseases, and can exert antitumor effects on several human cancer cell lines. However, little is known about the detailed mechanisms of the antitumor activity of Cepharanthine. In the present study, we determined whether Cepharanthine could suppress angiogenesis and growth of human oral squamous cell carcinoma (OSCC) cells in vitro and in vivo. Cepharanthine significantly inhibited expression of two major pro-angiogenic molecules, vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8), in cultured cells and in cells implanted into the subcutaneous tissue of nude mice. Also, Cepharanthine inhibited the nuclear factor-kappaB (NF-kappaB) activity in human OSCC cells in vitro and in vivo. The decreased expression of VEGF and IL-8 correlated with decreased tumor cell growth and decreased vascularization in vitro and in vivo. These findings suggest that Cepharanthine can suppress angiogenesis and growth of OSCC cells by inhibiting expression of VEGF and IL-8 involved in the blockade of NF-kappaB activity.
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- 2009
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13. Effects of cepharanthine alone and in combination with fluoropyrimidine anticancer agent, S-1, on tumor growth of human oral squamous cell carcinoma xenografts in nude mice.
- Author
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Harada K, Ferdous T, Itashiki Y, Takii M, Mano T, Mori Y, and Ueyama Y
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- Animals, Apoptosis drug effects, Benzylisoquinolines administration & dosage, Blotting, Western, Carcinoma, Squamous Cell metabolism, Carcinoma, Squamous Cell secondary, Cell Proliferation drug effects, Dihydrouracil Dehydrogenase (NADP) metabolism, Drug Combinations, Enzyme-Linked Immunosorbent Assay, Female, Humans, Immunoenzyme Techniques, In Situ Nick-End Labeling, Male, Mice, Mice, Nude, Mouth Neoplasms metabolism, Mouth Neoplasms pathology, Orotate Phosphoribosyltransferase metabolism, Oxonic Acid administration & dosage, Tegafur administration & dosage, Thymidylate Synthase metabolism, Tumor Cells, Cultured, Xenograft Model Antitumor Assays, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Carcinoma, Squamous Cell drug therapy, Mouth Neoplasms drug therapy
- Abstract
Background: Chemotherapy has shown little antitumor activity against advanced oral squamous cell carcinoma (OSCC) patients. Therefore, there is an urgent need to develop more effective therapeutic methods for patients with advanced OSCC. Cepharanthine is a biscoclaurine alkaloid extracted from Stephania cepharantha Hayata, which is widely used for the treatment of many acute and chronic diseases, and can exert antitumor effects on several human cancer cells. S-1 is a new oral antineoplastic agent that can induce apoptosis in various types of cancer cells, including OSCC. Hence combined treatment of cancer cells with cepharanthine and S-1 might exert dramatic antitumor effects on OSCC cells., Materials and Methods: In this study, the response of human OSCC cells to cepharanthine alone and in combination with S-1 was examined using nude mouse xenograft models. S-1 (10 mg/kg/day, 5 times/week) was administered orally and cepharanthine (20 mg/kg, 5 times/week) was injected into peritumoral tissue for three weeks. Apoptotic cells were detected by a TUNEL method. The protein expression of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), and orotate phosphoribosyl transferase (OPRT) were assessed using immunohistochemistry; their gene expression was determined using microdissection and RT-PCR, and their protein levels using ELISA., Results: Combined therapy of cepharanthine and S-1 exerted antitumor effects on human OSCC xenografts markedly and significantly induced apoptotic cells in tumors treated with cepharanthine plus S-1. Immunohistochemistry showed that the expressions of TS and DPD were down-regulated, and that OPRT expression was up-regulated in tumors treated with cepharanthine plus S-1. In the same way, microdissection and RT-PCR revealed that the expression of TS and DPD mRNA was down-regulated and that expression of OPRT mRNA was up-regulated in tumors administered the combined treatment. Moreover, ELISA indicated that the protein levels of TS and DPD were down-regulated, and that OPRT was up-regulated in tumors treated with the combined therapy. During the experimental period, no loss of body weight was observed in mice treated with the combined therapy., Conclusion: These findings demonstrate that the combination of cepharanthine and S-1 is effective against OSCC and has the potential of being a new therapeutic tool for future treatment of these tumors.
- Published
- 2009
14. Effects of tumor necrosis factor-related apoptosis-inducing ligand alone and in combination with fluoropyrimidine anticancer agent, S-1, on tumor growth of human oral squamous cell carcinoma xenografts in nude mice.
- Author
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Itashiki Y, Harada K, Ferdous T, and Yoshida H
- Subjects
- Animals, Apoptosis drug effects, Body Weight drug effects, Carcinoma, Squamous Cell enzymology, Carcinoma, Squamous Cell genetics, Carcinoma, Squamous Cell pathology, Cell Growth Processes drug effects, Cell Line, Tumor, Dihydrouracil Dehydrogenase (NADP) biosynthesis, Dihydrouracil Dehydrogenase (NADP) genetics, Drug Combinations, Drug Synergism, Female, Gene Expression, Humans, Mice, Mice, Nude, Orotate Phosphoribosyltransferase biosynthesis, Orotate Phosphoribosyltransferase genetics, Oxonic Acid administration & dosage, RNA, Messenger biosynthesis, RNA, Messenger genetics, TNF-Related Apoptosis-Inducing Ligand administration & dosage, Tegafur administration & dosage, Thymidylate Synthase biosynthesis, Thymidylate Synthase genetics, Xenograft Model Antitumor Assays, Antineoplastic Combined Chemotherapy Protocols pharmacology, Carcinoma, Squamous Cell drug therapy, TNF-Related Apoptosis-Inducing Ligand pharmacology
- Abstract
Background: Chemotherapy has shown little antitumor activity against advanced oral squamous cell carcinoma (OSCC) patients. Therefore, there is an urgent need to develop more effective therapeutic methods for patients with advanced OSCC. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor ligand family that selectively induces apoptosis of cancer cells. S-1 is a new oral antineoplastic agent that can induce apoptosis in various types of cancer cells, including OSCC. Hence, combined treatment of cancer cells with TRAIL and S-1 might exert dramatic antitumor effects on OSCC cells., Materials and Methods: In this study, the response of human OSCC cells to TRAIL alone and in combination with S-1 was examined using nude mouse xenograft models. S-1 (10 mg/kg/day, 5 times/week) was administered orally and TRAIL (1 mg/kg, 5 times/week) was injected into peritumoral tissue for three weeks. Apoptotic cells were detected by a TUNEL method. The protein expression of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), and orotate phosphoribosyl transferase (OPRT) were assessed using immunohistochemistry; their gene expression was determined using microdissection and RT-PCR, and their protein levels using ELISA., Results: Combined therapy of TRAIL and S-1 exerted antitumor effects on human OSCC xenografts markedly and significantly induced apoptotic cells in tumors treated with TRAIL plus S-1. Immunohistochemistry showed that the expressions of TS and DPD were down-regulated, and that OPRT expression was up-regulated in tumors treated with TRAIL plus S-1. In the same way, microdissection and RT-PCR revealed that the expression of TS and DPD mRNA was down-regulated and that expression of OPRT mRNA was up-regulated in tumors administered the combined treatment. Moreover, ELISA indicated that the protein levels of TS and DPD were down-regulated, and that OPRT was up-regulated in tumors treated with the combined therapy. During the experimental period, no loss of body weight was observed in mice treated with the combined therapy., Conclusion: These findings demonstrate that the combination of TRAIL and S-1 is effective against OSCC and has the potential of being a new therapeutic tool for future treatment of these tumors.
- Published
- 2007
15. Down-regulation of S-phase kinase associated protein 2 (Skp2) induces apoptosis in oral cancer cells.
- Author
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Harada K, Supriatno, Kawashima Y, Itashiki Y, Yoshida H, and Sato M
- Subjects
- Animals, Caspases metabolism, Cell Division, DNA Fragmentation, DNA, Neoplasm genetics, Humans, Mice, Mice, Inbred BALB C, Mice, Nude, Mouth Neoplasms genetics, Mouth Neoplasms pathology, Neoplasm Transplantation, Oligonucleotides, Antisense, Transplantation, Heterologous, Tumor Cells, Cultured, Apoptosis, Down-Regulation, Mouth Neoplasms metabolism, Neoplasm Proteins metabolism, S-Phase Kinase-Associated Proteins metabolism
- Abstract
S-phase kinase associated protein 2 (Skp2) is a member of an F-box family of substrate-recognition subunits of SCF ubiquitin-protein ligase complexes that has been implicated in the ubiquitin-mediated degradation of several key regulators of mammalian G1 progression, including the cyclin-dependent kinase inhibitor p27Kip1, a dosage-dependent tumor suppressor protein. The anti-sense effect was confirmed in two cell lines of oral cancer cells that also exhibited over-expression of the Skp2 protein. In this study, we examined the mechanism responsible for anti-sense-mediated growth inhibition of oral cancer cells in vitro and in vivo. Skp2-anti-sense treatment induced apoptosis characterized by an increase in the early apoptosis, fragmentation of nuclei and activation of caspase-3, -8 and -9. Moreover, the growth of xenograft tumors was markedly suppressed by Skp2-anti-sense treatment. Furthermore, histological specimen revealed apoptotic cell death was increased in Skp2-anti-sense treated tumors. Our results suggest that down-regulation of Skp2 appears to induce apoptosis in oral cancer cells, targeting this molecule could represent a promising new therapeutic approach for this type of cancer.
- Published
- 2005
- Full Text
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16. High expression of S-phase kinase-associated protein 2 (Skp2) is a strong prognostic marker in oral squamous cell carcinoma patients treated by UFT in combination with radiation.
- Author
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Harada K, Supriatno, Kawaguchi S, Kawashima Y, Itashiki Y, Yoshida H, and Sato M
- Subjects
- Adult, Aged, Aged, 80 and over, Antineoplastic Combined Chemotherapy Protocols administration & dosage, Carcinoma, Squamous Cell drug therapy, Carcinoma, Squamous Cell radiotherapy, Combined Modality Therapy, Female, Humans, Immunohistochemistry, Male, Middle Aged, Mouth Neoplasms drug therapy, Mouth Neoplasms radiotherapy, Prognosis, Survival Rate, Tegafur administration & dosage, Uracil administration & dosage, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Carcinoma, Squamous Cell metabolism, Carcinoma, Squamous Cell therapy, Mouth Neoplasms metabolism, Mouth Neoplasms therapy, S-Phase Kinase-Associated Proteins biosynthesis
- Abstract
Low expression of p27(Kip1) is associated with disease progression and an unfavorable outcome in several malignancies including oral squamous cell carcinoma (SCC). In addition, p27(Kip1) protein is thought to be degraded by Skp2 (S-phase kinase-associated protein 2). The purpose of this study was to examine whether Skp2 expression can be a useful prognostic factor in oral SCC patients treated by UFT in combination with radiation. The Skp2 expression was investigated by immunohistochemistry in biopsy samples from 102 oral SCC patients, who were treated by UFT in combination with radiation. Associations of each expression with the clinicopathological characteristics and patient survival were also analyzed. A significant association was found between Skp2 expression and tumor size (p = 0.0462), cervical lymph node metastasis (p = 0.0209), therapeutic effect (p = 0.0490) and patient outcome (p = 0.0002). The 5-year survival rates of Skp2 high and low expression tumors were 40.5% and 78.5%, respectively, and this difference was significant (p = 0.0001) by log-rank test. Multivariate analysis revealed that reduced term of survival was related to high levels of Skp2 expression (p = 0.0001). These results suggest that Skp2 may be a useful prognostic factor in oral SCC patients treated by UFT in combination with radiation.
- Published
- 2005
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