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Kidokoro H, Kubota T, Hayashi N, Hayakawa M, Takemoto K, Kato Y, Okumura A. Absent cyclicity on aEEG within the first 24 h is associated with brain damage in preterm infants. Neuropediatrics 2010; 41:241-5. [PMID: 21445813 DOI: 10.1055/s-0030-1270479] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE Our aim was to clarify the relationship between amplitude-integrated electroencephalographic (aEEG) findings before 24 h of age in preterm infants and neurodevelopmental outcome. DESIGN 12 infants born between 27 and 32 weeks of gestation were eligible. The recordings of aEEG and conventional EEG were started within 12 h after birth. The background aEEG findings were evaluated and classified. Additionally, we evaluated the absence or presence of changes on the lower border of the aEEG. RESULTS All infants had discontinuous normal voltage background on aEEG, corresponding to decreased or normal continuity on conventional EEG. Cyclicity on aEEG was seen in 8 of 12 infants within 24 h of age, and all of these infants had favourable outcomes. Cyclicity on aEEG was not recognized in 4 infants. 3 of the 4 infants with absent cyclicity had abnormal neurodevelopmental outcomes at 12 months. One of these infants had intraventricular haemorrhage (grade 2) with delayed development, and 2 had cystic periventricular leukomalacia followed by spastic diplegia. CONCLUSION Absent cyclicity on aEEG within 24 h of age was associated with poor outcome in preterm infants.
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Hayakawa M, Kasahara Y, Nakamura T, Muto F, Horie T, Maekawa S, Hobara Y, Rozhnoi AA, Solovieva M, Molchanov OA. A statistical study on the correlation between lower ionospheric perturbations as seen by subionospheric VLF/LF propagation and earthquakes. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009ja015143] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kotani T, Sumigama S, Hayakawa H, Mano Y, Tsuda H, Sugiyama C, Kawachi F, Hironaka M, Kato T, Kaneko K, Hayakawa M, Kikkawa F. Elevated levels of aldosterone in the amniotic fluid in two cases of congenital mesoblastic nephroma. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2010; 36:256-258. [PMID: 20455206 DOI: 10.1002/uog.7637] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Horiguchi A, Asano T, Kuroda K, Sato A, Asakuma J, Ito K, Hayakawa M, Sumitomo M, Asano T. STAT3 inhibitor WP1066 as a novel therapeutic agent for renal cell carcinoma. Br J Cancer 2010; 102:1592-9. [PMID: 20461084 PMCID: PMC2883159 DOI: 10.1038/sj.bjc.6605691] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Background: Signal transducer and activator of transcription 3 (STAT3) regulates the expression of genes that mediate cell survival, proliferation, and angiogenesis and is aberrantly activated in various types of malignancies, including renal cell carcinoma (RCC). We examined whether it could be a novel therapeutic target for RCC by using the STAT3 inhibitor WP1066. Methods: The antitumour activities and related mechanisms of WP1066 were investigated in vitro on renal cancer cell lines and in vivo on murine xenografts. Results: In Caki-1 and 786-O renal cancer cells, 5 μM WP1066 prevented the phosphorylation of STAT3, and 2.5 μM WP1066 significantly (P<0.01) inhibited cell survival and proliferation. WP1066 suppressed the expression of Bcl-2, induced apoptosis, and inhibited the basal and hypoxia-induced expression of HIF1α and HIF2α, as well as vascular endothelial growth factor secretion into cell culture medium. Human umbilical vascular endothelial cells cocultured with media from WP1066-treated cells showed significantly reduced tubulogenesis (P<0.05). Systemic oral administration of WP1066 to mice for 19 days significantly inhibited the growth of Caki-1 xenograft tumours (P<0.05), and pathological analysis of xenografts of WP1066-treated mice showed decreased immunostaining of phosphorylated STAT3 and reduced length of CD34-positive vessels (P<0.05). Conclusion: Our results suggest that using WP1066 to inhibit the STAT3 signalling pathway could be a novel therapeutic strategy against RCC.
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Maruyama T, Onda K, Hayakawa M, Suzuki T, Kimizuka T, Matsui T, Takasu T, Nagase I, Hamada N, Ohta M. Synthesis and Evaluation of Novel Phenylethanolamine Derivatives containing Acetanilides as Potent and Selective .BETA.3-Adrenergic Receptor Agonists. Chem Pharm Bull (Tokyo) 2010; 58:533-45. [DOI: 10.1248/cpb.58.533] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Taylor RA, Callison RC, Martin CO, Hayakawa M, Chaloupka JC. Acutely ruptured intracranial saccular aneurysms treated with stent assisted coiling: complications and outcomes in 42 consecutive patients. J Neurointerv Surg 2009; 2:23-30. [PMID: 21990554 DOI: 10.1136/jnis.2009.001693] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Antiplatelet agents are required to prevent thromboembolic complications from recently deployed intracranial stents, yet they carry a risk of bleeding complications that may be serious in patients with recent subarachnoid hemorrhage. METHOD Consecutive patients at a single institution who had ruptured intracranial saccular aneurysms treated with stent assisted coiling were retrospectively reviewed. Our primary outcomes were ischemic stroke related to the stent and bleeding complications possibly related to antithrombotic therapy. Secondary outcomes included 3 month follow-up National Institute of Health Stroke Scale (NIHSS) scores and modified Rankin Scale (mRS) scores. RESULTS 44 aneurysms in 42 patients were treated. Seven patients experienced ischemic strokes during their hospitalization. Five ischemic strokes were secondary to vasospasm; one was definitely related to thrombus formation within the stent and one was possibly related to the stent. Two patients had asymptomatic intracranial hemorrhages and one patient had a symptomatic intracranial hemorrhage. Patients with Hunt and Hess grades I-II (n=25) experienced no stent associated ischemic strokes or symptomatic intracranial hemorrhages. The two stent associated ischemic strokes and one symptomatic intracranial hemorrhage occurred in patients with Hunt and Hess grades III-V (n=17) and patients with external ventricular drains (EVDs) (n=17). Only one patient had disability at the 3 month follow-up that was possibly related to the stent (mRS score of 3 and NIHSS score of 2). CONCLUSION These data suggest that higher grade hemorrhage patients, especially those with EVDs, are at greater risk for ischemic stroke and/or bleeding complications than lower grade patients. However, the complications had a small impact on mid-term disability outcomes in this cohort.
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Hayakawa M, Oomura M, Sadato A, Tanaka T, Irie K, Negoro M, Kato Y, Sano H. FP18-TU-01 Additional endovascular treatment for acute ischemic stroke patients unresponsive to intravenous recombinant tissue plasminogen activator. J Neurol Sci 2009. [DOI: 10.1016/s0022-510x(09)70356-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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58
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Tahara A, Matsuyama-Yokono A, Nakano R, Someya Y, Hayakawa M, Shibasaki M. Antihyperglycemic effects of ASP8497 in streptozotocin-nicotinamide induced diabetic rats: comparison with other dipeptidyl peptidase-IV inhibitors. Pharmacol Rep 2009; 61:899-908. [DOI: 10.1016/s1734-1140(09)70147-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 09/25/2009] [Indexed: 10/25/2022]
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Maruyama T, Seki N, Onda K, Suzuki T, Kawazoe S, Hayakawa M, Matsui T, Takasu T, Ohta M. Discovery of novel thiourea derivatives as potent and selective β3-adrenergic receptor agonists. Bioorg Med Chem 2009; 17:5510-9. [DOI: 10.1016/j.bmc.2009.06.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Revised: 06/15/2009] [Accepted: 06/16/2009] [Indexed: 10/20/2022]
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Taylor R, Callison R, Martin C, Hayakawa M, Chaloupka J. 022 Ischemic stroke versus bleeding risk in patients with acutely ruptured saccular aneurysms treated with stent assisted coiling. J Neurointerv Surg 2009. [DOI: 10.1136/jnis.2009.000851v] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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61
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Otoguro M, Tamura T, Suzuki KI, Hayakawa M. Saccharothrix violaceirubra sp. nov., isolated from soil and plant litter. Int J Syst Evol Microbiol 2009; 59:1504-7. [DOI: 10.1099/ijs.0.003723-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Mato N, Fujii M, Hakamata Y, Kobayashi E, Sato A, Hayakawa M, Ohto-Ozaki H, Bando M, Ohno S, Tominaga S, Sugiyama Y. Interleukin-1 receptor-related protein ST2 suppresses the initial stage of bleomycin-induced lung injury. Eur Respir J 2009; 33:1415-28. [PMID: 19196821 DOI: 10.1183/09031936.00084307] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Acute lung injury has a range of causes, and occasionally leads to lethal respiratory failure. Despite advances in treatment, acute lung injury continues to have a high mortality rate, and thus a new therapeutic approach is needed. ST2 is an interleukin (IL)-1 receptor-related protein, and its expression is induced by various inflammatory responses. Recently, ST2 has been speculated to exert anti-inflammatory effects; therefore, we investigated the role of the ST2 in the murine model of acute lung injury. To elucidate the function of ST2 in vivo, mice that transiently overexpressed ST2 protein were prepared using the hydrodynamic gene transfer method, and lung injury was induced by intratracheal administration of bleomycin. In bleomycin-treated ST2-overexpressing mice, the increase of neutrophils in the bronchoalveolar lavage fluid (BALF) was markedly suppressed. Additionally, the levels of tumour necrosis factor-alpha and IL-6, as well as the concentration of albumin, in BALF were reduced compared with those of controls. Furthermore, the pulmonary architecture in ST2-overexpressing mice remained almost normal, and the survival rate was significantly improved. From these results, we concluded that ST2 has the potential to suppress the initial stage of acute lung injury, and therefore it may be a useful reagent for the treatment of acute lung injury.
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Maruyama T, Onda K, Hayakawa M, Seki N, Takahashi T, Moritomo H, Suzuki T, Matsui T, Takasu T, Nagase I, Ohta M. Synthesis and evaluation of novel phenoxypropanolamine derivatives containing acetanilides as potent and selective β3-adrenergic receptor agonists. Bioorg Med Chem 2009; 17:3283-94. [DOI: 10.1016/j.bmc.2009.03.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 03/23/2009] [Accepted: 03/24/2009] [Indexed: 11/17/2022]
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Matsuyama-Yokono A, Tahara A, Nakano R, Someya Y, Shiraki K, Hayakawa M, Shibasaki M. Antidiabetic effects of dipeptidyl peptidase-IV inhibitors and sulfonylureas in streptozotocin-nicotinamide-induced mildly diabetic mice. Metabolism 2009; 58:379-86. [PMID: 19217455 DOI: 10.1016/j.metabol.2008.10.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Accepted: 10/06/2008] [Indexed: 11/29/2022]
Abstract
The present study investigated the antidiabetic effects of the dipeptidyl peptidase (DPP)-IV inhibitors ASP8497 and vildagliptin, and the sulfonylureas glibenclamide and gliclazide in streptozotocin-nicotinamide-induced mildly diabetic mice. A single administration of ASP8497 and vildagliptin significantly improved glucose tolerance by increasing plasma insulin and glucagon-like peptide-1 levels. In addition, a single administration of glibenclamide and gliclazide also caused significant improvement in glucose tolerance with an accompanying increase in the plasma insulin level. Subsequently, the effects of a 1-week chronic daily dosing of DPP-IV inhibitors and sulfonylureas were investigated. All drugs significantly improved glucose tolerance on day 1 of chronic daily dosing. After 1 week of chronic daily dosing, the DPP-IV inhibitors caused a significant improvement in glucose tolerance similar to those observed on day 1 by increasing the plasma insulin and glucagon-like peptide-1 levels. In contrast, the sulfonylureas had no significant improving or insulinotropic effect. Furthermore, ASP8497 also had an antihyperglycemic effect and improved pancreatic histopathologic lesions in a 4-week chronic daily dosing study. These results suggest that chronic daily dosing of sulfonylureas had virtually no antidiabetic effects because of marked attenuation of the insulinotropic action in streptozotocin-nicotinamide-induced mildly diabetic mice. In contrast, the antidiabetic efficacy of DPP-IV inhibitors, including ASP8497, did not change even after chronic daily dosing; therefore, DPP-IV inhibitors are useful as a therapeutic agent for impaired glucose tolerance and type 2 diabetes mellitus.
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Hayakawa M, Niijima S. [Topics on neonatal neurology. Introduction]. NO TO HATTATSU = BRAIN AND DEVELOPMENT 2009; 41:100-102. [PMID: 19517773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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66
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Tahara A, Matsuyama-Yokono A, Nakano R, Someya Y, Hayakawa M, Shibasaki M. Evaluation of the Antidiabetic Effects of Dipeptidyl Peptidase-IV Inhibitor ASP8497 in Streptozotocin-Nicotinamide-Induced Mildly Diabetic Mice. Pharmacology 2009; 83:177-87. [DOI: 10.1159/000196813] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Accepted: 11/03/2008] [Indexed: 11/19/2022]
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Tahara A, Matsuyama-Yokono A, Nakano R, Someya Y, Hayakawa M, Shibasaki M. Effects of the combination of dipeptidyl peptidase-IV inhibitor ASP8497 and antidiabetic drugs in streptozotocin-nicotinamide-induced mildly diabetic mice. Eur J Pharmacol 2009; 605:170-6. [PMID: 19171131 DOI: 10.1016/j.ejphar.2008.12.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2008] [Revised: 12/08/2008] [Accepted: 12/23/2008] [Indexed: 11/26/2022]
Abstract
Several combination therapies have been investigated in an effort to achieve and maintain glycemic control in patients with type 2 diabetes. In this study, we combined the novel dipeptidyl peptidase (DPP)-IV inhibitor ASP8497 with the antidiabetic drugs metformin, glibenclamide, voglibose, rosiglitazone, and insulin to examine the effects of each combination on glucose tolerance in streptozotocin-nicotinamide-induced mildly diabetic mice. Single treatments with ASP8497 (1 mg/kg), metformin (300 mg/kg), glibenclamide (3 mg/kg), voglibose (0.3 mg/kg), rosiglitazone (10 mg/kg), or insulin (0.2 IU/kg) significantly improved glucose tolerance during the liquid meal tolerance test. In addition, combination treatment with ASP8497 and each antidiabetic drug additively improved glucose tolerance. Among these, the combination of ASP8497 and glibenclamide or insulin additively ameliorated glucose tolerance with an additive increase in the plasma insulin level; however, it did not affect the fasting blood glucose lowering effects of glibenclamide or insulin. These profiles indicate that the combination of ASP8497 with existing antidiabetic drugs could be useful for correcting the postprandial hyperglycemia seen with type 2 diabetes.
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Uno S, Hayakawa M. QED in Finite Volume and Finite Size Scaling Effect on Electromagnetic Properties of Hadrons. ACTA ACUST UNITED AC 2008. [DOI: 10.1143/ptp.120.413] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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69
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Matsuyama-Yokono A, Tahara A, Nakano R, Someya Y, Nagase I, Hayakawa M, Shibasaki M. ASP8497 is a novel selective and competitive dipeptidyl peptidase-IV inhibitor with antihyperglycemic activity. Biochem Pharmacol 2008; 76:98-107. [DOI: 10.1016/j.bcp.2008.03.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2008] [Revised: 03/31/2008] [Accepted: 03/31/2008] [Indexed: 01/30/2023]
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Hobara Y, Walker SN, Balikhin M, Pokhotelov OA, Gedalin M, Krasnoselskikh V, Hayakawa M, André M, Dunlop M, Rème H, Fazakerley A. Cluster observations of electrostatic solitary waves near the Earth's bow shock. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007ja012789] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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71
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Hayakawa M, Momose Y, Yamazaki T, Nonomura H. A method for the selective isolation ofMicrotetraspora glaucaand related four-spored actinomycetes from soil. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1996.tb03232.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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72
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Osborne SL, Wen PJ, Boucheron C, Nguyen HN, Hayakawa M, Kaizawa H, Parker PJ, Vitale N, Meunier FA. PIKfyve Negatively Regulates Exocytosis in Neurosecretory Cells. J Biol Chem 2008; 283:2804-13. [DOI: 10.1074/jbc.m704856200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Jefferies HBJ, Cooke FT, Jat P, Boucheron C, Koizumi T, Hayakawa M, Kaizawa H, Ohishi T, Workman P, Waterfield MD, Parker PJ. A selective PIKfyve inhibitor blocks PtdIns(3,5)P(2) production and disrupts endomembrane transport and retroviral budding. EMBO Rep 2008; 9:164-70. [PMID: 18188180 PMCID: PMC2246419 DOI: 10.1038/sj.embor.7401155] [Citation(s) in RCA: 230] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Revised: 11/22/2007] [Accepted: 11/23/2007] [Indexed: 11/23/2022] Open
Abstract
Phosphoinositides have crucial roles in cellular controls, many of which have been established through the use of small-molecule inhibitors. Here, we describe YM201636, a potent inhibitor of the mammalian class III phosphatidylinositol phosphate kinase PIKfyve, which synthesizes phosphatidylinositol 3,5-bisphosphate. Acute treatment of cells with YM201636 shows that the PIKfyve pathway is involved in the sorting of endosomal transport, with inhibition leading to the accumulation of a late endosomal compartment and blockade of retroviral exit. Inhibitor specificity is shown by the use of short interfering RNA against the target, as well as by rescue with the drug-resistant yeast orthologue Fab1. We concluded that the phosphatidylinositol 3,5-bisphosphate pathway is integral to endosome formation, determining morphology and cargo flux.
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Sorokin VM, Yashchenko AK, Hayakawa M. Electric field perturbation caused by an increase in conductivity related to seismicity-induced atmospheric radioactivity growth. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2007. [DOI: 10.1134/s1990793107060206] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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75
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Raynaud FI, Eccles S, Clarke PA, Hayes A, Nutley B, Alix S, Henley A, Di-Stefano F, Ahmad Z, Guillard S, Bjerke LM, Kelland L, Valenti M, Patterson L, Gowan S, de Haven Brandon A, Hayakawa M, Kaizawa H, Koizumi T, Ohishi T, Patel S, Saghir N, Parker P, Waterfield M, Workman P. Pharmacologic characterization of a potent inhibitor of class I phosphatidylinositide 3-kinases. Cancer Res 2007; 67:5840-50. [PMID: 17575152 DOI: 10.1158/0008-5472.can-06-4615] [Citation(s) in RCA: 295] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Extensive evidence implicates activation of the lipid phosphatidylinositide 3-kinase (PI3K) pathway in the genesis and progression of various human cancers. PI3K inhibitors thus have considerable potential as molecular cancer therapeutics. Here, we detail the pharmacologic properties of a prototype of a new series of inhibitors of class I PI3K. PI103 is a potent inhibitor with low IC50 values against recombinant PI3K isoforms p110alpha (2 nmol/L), p110beta (3 nmol/L), p110delta (3 nmol/L), and p110gamma (15 nmol/L). PI103 also inhibited TORC1 by 83.9% at 0.5 micromol/L and exhibited an IC50 of 14 nmol/L against DNA-PK. A high degree of selectivity for the PI3K family was shown by the lack of activity of PI103 in a panel of 70 protein kinases. PI103 potently inhibited proliferation and invasion of a wide variety of human cancer cells in vitro and showed biomarker modulation consistent with inhibition of PI3K signaling. PI103 was extensively metabolized, but distributed rapidly to tissues and tumors. This resulted in tumor growth delay in eight different human cancer xenograft models with various PI3K pathway abnormalities. Decreased phosphorylation of AKT was observed in U87MG gliomas, consistent with drug levels achieved. We also showed inhibition of invasion in orthotopic breast and ovarian cancer xenograft models and obtained evidence that PI103 has antiangiogenic potential. Despite its rapid in vivo metabolism, PI103 is a valuable tool compound for exploring the biological function of class I PI3K and importantly represents a lead for further optimization of this novel class of targeted molecular cancer therapeutic.
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