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Dive into the research topics where Naoki Takezako is active.

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Featured researches published by Naoki Takezako.


Molecular and Cellular Biochemistry | 2010

ST2 gene expression is proliferation-dependent and its ligand, IL-33, induces inflammatory reaction in endothelial cells

Shinsuke Aoki; Morisada Hayakawa; Hiromi Ozaki; Naoki Takezako; Hiroto Obata; Nobuhiro Ibaraki; Tadahiko Tsuru; Shin-ichi Tominaga; Ken Yanagisawa

ST2 gene products that are members of IL-1 receptor family are expressed in various cells such as growth-stimulated fibroblasts and Th2 helper T-cells, and recently, IL-33, which belongs to IL-1 family, was identified as the ligand for ST2L, the receptor type product of the ST2 gene. Subsequently, IL-33 and ST2L have been reported to be involved in Th2 immunity and inflammation, however, their functions on non-immunological cells are still obscure. Among non-immunological adhesive cells, vascular endothelial cells were reported to express both ST2 gene products and IL-33, therefore, we investigated the expression manner of the ST2 gene in vascular endothelial cells and the effect of IL-33 on endothelial cells. ST2 gene was expressed in each of the vascular endothelial cell types tested, and the expression was growth-dependent and down-regulated when the cells were differentiated to form vascular structures on the extracellular membrane matrix. IL-33 scarcely affected the growth and tube formation of the endothelial cells, but induced IL-6 and IL-8 secretion from endothelial cells with the rapid activation of extracellular signal-regulated kinase (ERK) 1/2, so IL-33 is supposed to involve in inflammatory reaction of vascular endothelial cells through its receptor, ST2L.


American Journal of Hematology | 2015

Shorter halving time of BCR-ABL1 transcripts is a novel predictor for achievement of molecular responses in newly diagnosed chronic-phase chronic myeloid leukemia treated with dasatinib: Results of the D-first study of Kanto CML study group

Noriyoshi Iriyama; Shin Fujisawa; Chikashi Yoshida; Hisashi Wakita; Shigeru Chiba; Shinichiro Okamoto; Kimihiro Kawakami; Naoki Takezako; Takashi Kumagai; Koiti Inokuchi; Kazuma Ohyashiki; Jun Taguchi; Shingo Yano; Tadahiko Igarashi; Yasuji Kouzai; Satoshi Morita; Junichi Sakamoto; Hisashi Sakamaki

To investigate the factors that affect molecular responses on dasatinib treatment in patients with chronic‐phase chronic myeloid leukemia (CML‐CP), we performed a clinical trial named the “D‐First study.” Fifty‐two patients with newly diagnosed CML‐CP were enrolled in this study and received 100 mg dasatinib once daily. A deep molecular response (DMR) was defined as <50 copies/μg RNA of BCR‐ABL1 transcript value corrected by GAPDH, which ensures <0.01% of BCR‐ABL1 transcript value according to International Scale (BCR‐ABL1IS). The halving time for BCR‐ABL1 transcripts was calculated using transcript levels before dasatinib treatment, transcript levels after 3 months of treatment, and the treatment time between these two points. In terms of molecular response, 38 of 51 (75%) patients reached major molecular response (MMR) by 12 months, and the rate of DMR by 18 months was 59% (30/51). While both BCR‐ABL1 transcript levels before treatment and a shorter halving time of BCR‐ABL1 transcripts (≤14 days) were significant factors affecting achievement of MMR by 12 months, the Sokal score at diagnosis was not associated with MMR. Importantly, the halving time was the only factor that predicted achievement of DMR by 18 months. We showed that patients with CML‐CP treated with dasatinib can be stratified according to the early treatment response as determined by the halving time of BCR‐ABL1 transcripts. These data emphasize the significance of the early response from dasatinib treatment in achieving a DMR. (ClinicalTrials.gov; NCT01464411) Am. J. Hematol. 90:282–287, 2015.


Leukemia & Lymphoma | 2000

Pyogenic Granuloma of the Tongue Early after Allogeneic Bone Marrow Transplantation for Multiple Myeloma

Yoshinobu Kanda; Chiaki Arai; Aki Chizuka; Miyuki Suguro; Tamae Hamaki; Rie Yamamoto; Yayoi Yamauchi; Tomohiro Matsuyama; Naoki Takezako; Yuko Shira; Akiyoshi Miwa; Koji Iwasaki; Michiyo Nasu; Atsushi Togawa

Oral complications occur frequently after bone marrow transplantation (BMT). Some of them are caused by regimen-related toxicity of the preparative regimen, and others by infections. In addition, oral tissues are targets of graft-versus-host disease (GVHD). Oral granulomatous lesions are not a common complication after BMT, and are especially rare on the tongue. Such rare lesions reported in the literature, developed late after BMT with oral chronic GVHD. We present here a patient who developed pyogenic granuloma of the tongue early after allogeneic BMT done for multiple myeloma. Regimen-related mucositis, oral acute GVHD, the administration of cyclosporine A, and the preexisting macroglossia might be responsible for the formation of granuloma.


American Journal of Hematology | 2015

Early cytotoxic lymphocyte expansion contributes to a deep molecular response to dasatinib in patients with newly diagnosed chronic myeloid leukemia in the chronic phase: results of the D-first study.

Noriyoshi Iriyama; Shin Fujisawa; Chikashi Yoshida; Hisashi Wakita; Shigeru Chiba; Shinichiro Okamoto; Kimihiro Kawakami; Naoki Takezako; Takashi Kumagai; Koiti Inokuchi; Kazuma Ohyashiki; Jun Taguchi; Shingo Yano; Tadahiko Igarashi; Yasuji Kouzai; Satoshi Morita; Junichi Sakamoto; Hisashi Sakamaki

Dasatinib is one of the key treatment options for chronic myeloid leukemia (CML) patients. Increase in lymphocyte counts has been known to be predictive of a good treatment response under dasatinib treatment as a second line therapy. However, clinical significance of lymphocyte dynamics in the upfront setting has yet to be clarified. To investigate the significance of lymphocyte dynamics in newly diagnosed chronic phase (CP)‐CML, patient data of D‐First study (ClinicalTrials.gov NCT01464411) were analyzed. Fifty‐two CML‐CP patients enrolled to this study were treated with dasatinib (100 mg day−1) and all were followed‐up for 18 months. The incidence of lymphocyosis was observed in 14 (27%), but it was not associated with deep molecular response achievement. However, natural killer (NK) cell or cytotoxic T lymphocyte (CTL) counts at 1 month were significantly higher in patients with deep molecular response (DMR) by 18 months compared to those without DMR. When the patients were divided into two groups according to those calculated thresholds by receiver operating characteristic curve (407/μL for NK cells and 347/μL for CTLs), the cumulative DMR rates by 18 months were significantly better in higher value group compared to lower value group. In contrast, regulatory T cell counts were significantly lower at 12 and 15 months in patients achieved DMR. These results suggest the presence of dual effects of dasatinib on immune system through the cytotoxic lymphocytes activation and Treg deregulation in different periods in newly diagnosed CML‐CP. Am. J. Hematol. 90:819–824, 2015.


Leukemia & Lymphoma | 2000

Prognostic Significance of Serum Soluble Interleukin-2 Receptor Level in Non-Hodgkin's Lymphoma: A Single Center Study in Japan

Natsu Kono; Yoshinobu Kanda; Rie Yamamoto; Aki Chizuka; Miyuki Suguro; Tamae Hamaki; Chiaki Arai; Tomohiro Matsuyama; Naoki Takezako; Akiyoshi Miwa; Atsushi Togawa

Interleukin 2 receptor is expressed not only on the surface of activated T or B lymphocytes, but also on certain lymphoid malignancies. The receptor is released from the cell membrane as soluble form (sIL-2R). Serum sIL-2R level is a sensitive and quantitative marker of circulating peripheral blood mononuclear cell activation or specific tumor cell growth including non-Hodgkins lymphoma (NHL). However, the relevance of serum sIL-2R levels relating to clinical outcome in adult patients with NHL remains uncertain. Therefore, we investigated the serial serum sIL-2R levels in 28 untreated patients with NHL to evaluate its correlation with clinical characteristics. High serum sIL-2R level (>1000 U/ml) at diagnosis was associated with a high incidence of treatment failure (p=0.03) and poor overall survival (p=0.057). The serum sIL-2R levels decreased significantly after achieving complete remission (p=0.003). Further larger studies are required to evaluate whether serum sIL-2R level is an independent prognostic factor or not. However, adding this parameter to those already employed in the International Prognostic Index would perhaps provide a better prognostic index for adult patients with NHL.


Blood Cancer Journal | 2015

Trends of survival in patients with multiple myeloma in Japan: a multicenter retrospective collaborative study of the Japanese Society of Myeloma.

Shuji Ozaki; Hiroshi Handa; Takayuki Saitoh; Hirokazu Murakami; Mitsuhiro Itagaki; Hideki Asaoku; Kenshi Suzuki; Atsushi Isoda; Morio Matsumoto; Morio Sawamura; J Konishi; Kazutaka Sunami; Naoki Takezako; S Hagiwara; Yuko Kuroda; Takaaki Chou; E Nagura; Kazuyuki Shimizu

Trends of survival in patients with multiple myeloma in Japan: a multicenter retrospective collaborative study of the Japanese Society of Myeloma


Cellular & Molecular Immunology | 2012

Soluble ST2 protein inhibits LPS stimulation on monocyte-derived dendritic cells

Akihisa Nagata; Naoki Takezako; Hiroyuki Tamemoto; Hiromi Ohto-Ozaki; Satoshi Ohta; Shin-ichi Tominaga; Ken Yanagisawa

ST2 protein is a soluble splicing variant of ST2L protein, which is the receptor for interleukin-33 (IL-33). Previously, we reported that soluble ST2 suppressed the signal transduction of lipopolysaccharide (LPS) and cytokine production in monocytic cells. To investigate whether or not this inhibitory effect occurs in dendritic cells, which are the key players in innate and adaptive immunity, human monocyte-derived dendritic cells were pre-treated with soluble ST2 protein before LPS stimulation. Although soluble ST2 did not attenuate the LPS-induced maturation of dendritic cells, pre-treatment with soluble ST2 suppressed cytokine production and inhibited LPS signaling. Moreover, the proliferation of naive T cells was inhibited significantly by soluble ST2 pre-treatment. IL-33 had little effect on the cytokine production of immature monocyte-derived dendritic cells. Furthermore, soluble ST2 protein was internalized into dendritic cells, suggesting that soluble ST2 protein acts by a noncanonical mechanism other than the sequestration of IL-33.


American Journal of Hematology | 2000

High serum lactate dehydrogenase level predicts short survival after vincristine–doxorubicin–dexamethasone (VAD) salvage for refractory multiple myeloma

Miyuki Suguro; Yoshinobu Kanda; Rie Yamamoto; Aki Chizuka; Tamae Hamaki; Tomohiro Matsuyama; Naoki Takezako; Akiyoshi Miwa; Atsushi Togawa

We evaluated possible prognostic factors just before salvage therapy with vincristine, doxorubicin, and dexamethasone (VAD) for 36 patients with refractory multiple myeloma. The median duration from diagnosis to the first VAD salvage was 14 months (range 2–76 months). Among parameters that have been shown to be associated with poor survival, a high serum lactate dehydrogenase (LDH) level was the sole significant predictor of survival. The median survival of patients with high LDH levels was 4 months, whereas that of patients with low LDH levels was 20 months. A multivariate analysis identified high LDH and high age as independent prognostic factors. More aggressive therapies might be indicated for high‐LDH patients with refractory myeloma. Am. J. Hematol. 65:132–135, 2000.


Leukemia & Lymphoma | 2002

Prognostic Factors in Elderly Patients with Acute Myelogenous Leukemia: A Single Center Study in Japan

Yasuhito Nannya; Yoshinobu Kanda; Kumi Oshima; Makoto Kaneko; Rie Yamamoto; Aki Chizuka; Tamae Hamaki; Miyuki Suguro; Tomohiro Matsuyama; Naoki Takezako; Akiyoshi Miwa; Atsushi Togawa

We retrospectively analyzed data of 47 patients aged 60 years or older, hospitalized in our institution with the diagnosis of acute myelogenous leukemia (AML), and searched for prognostic factors. Induction with anthracyclines significantly correlated with better complete remission (CR) rate (P =0.0016) and overall survival (OS) (P <0.001). Another factor significantly affecting CR rate was higher age (>70 years) (P =0.042). Therapy-non-related factors predictive for shorter OS in univariate analyses were age older than 70 years (P =0.003), percentage of blasts in bone marrow more than 80% (P =0.048), serum lactate dehydrogenase level higher than 250   U   l m 1 (P =0.032). In stepwise cox proportional hazard regression model, all the four factors predictive for poor OS remained to be independently and significantly prognostic for shorter OS. Only two patients receiving anthracyclines died within 30 days and the frequency was not different from that in patients not receiving anthracyclines. The use of anthracyclines as induction therapy is recommended even in the elderly patients.


Leukemia & Lymphoma | 2001

Clinical Value of Serial Measurement of Serum C-Reactive Protein Level in Neutropenic Patients

Kan Yonemori; Yoshinobu Kanda; Rie Yamamoto; Tamae Hamaki; Miyuki Suguro; Aki Chizuka; Tomohiro Matsuyama; Naoki Takezako; Akiyoshi Miwa; Atsushi Togawa

C-reactive protein (CRP) is an acute phase reactant of inflammation. We evaluated the clinical value of serial measurement of CRP in neutropenic patients. CRP was shown to be useful to monitor the response to therapy for febrile episodes in neutropenia. However, we failed to show statistically significant differences in CRP levels between febrile episodes with or without clinically documented infection (p = 0.10) and with or without bacteremia (p = 0.55). Also, we could not predict febrile episodes within three days by the elevation of CRP value. The area under receiver-operating characteristic curve depicting the relationship between CRP levels and forthcoming febrile episodes was only 0.60. In conclusion, serial measurement of CRP was considered to be not useful to predict fever within three days, or to differentiate the types of infection.

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Akiyoshi Miwa

Jichi Medical University

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Naohiro Sekiguchi

Jikei University School of Medicine

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Kenshi Suzuki

Memorial Hospital of South Bend

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