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Featured researches published by Yasutaka Hoshi.


Cancer | 1990

Treatment of advanced neuroblastoma with emphasis on intensive induction chemotherapy. A report from the study group of Japan

Shigenori Sawaguchi; Michio Kaneko; Junichi Uchino; Takeo Takeda; Makoto Iwafuchi; Shiro Matsuyama; Hideyo Takahashi; Toshio Nakajo; Yasutaka Hoshi; Ikuo Okabe; Jotaro Yokoyama; Hirokazu Nishihira; Shingi Sasaki; Minoru Sakurai; Tadashi Sawada; Noboru Nagahara; Yoshiaki Tsuchida

One hundred nine newly treated patients with advanced neuroblastoma were entered in this study between January 1985 and May 1989. The eligible patients included infants younger than 12 months of age with Stage IVA disease (bone cortex, distant lymph node, and/or remote organ metastases) and patients aged 12 months or older with Stage III or IV disease (IVA plus IVB with tumor crossing the mid‐line and with metastases confined to bone marrow, liver, and skin). The patients first received six cyclic course of intensive chemotherapy (regimen A1), consisting of cyclophosphamide (1200 mg/m2), vincristine (1.5 mg/m2), tetrahydropyranyl adriamycin (pyrarubicin; 40 mg/m2), and cisplatin (90 mg/m2). Original tumors and the regional lymph node metastases were removed some time during these first six cycles of chemotherapy. The patients were further divided into three groups. Patients in course 1 received alternating treatment by regimen B (cyclophosphamide and ACNU) and intensified regimen A1, and those in course 2 were treated with alternating administration of regimen C (cyclophosphamide and DTIC) and intensified A1. Patients in course 3 were treated with bone marrow transplantation (BMT) preceded by high‐dose preconditioning chemotherapy. Survival rates were 77% in Stage III and 54% in Stage IV at 2 years, and 70% in Stage III and 45% in Stage IV at 3 years. The major toxicities encountered were bone marrow suppression with leukocyte counts down to 100/mm3, mild cystitis, and hearing impairment. The 2‐year survival rate was 78% in 21 patients who underwent BMT when complete remission was achieved. We concluded that our intensive induction chemotherapy is of significant value in increasing the rate of complete response, and in widening the indications for and achieving improved results of treatment with BMT.


Journal of Clinical Oncology | 2000

Six Months of Maintenance Chemotherapy After Intensified Treatment for Acute Lymphoblastic Leukemia of Childhood

Yasunori Toyoda; Atsushi Manabe; Masahiro Tsuchida; Ryohji Hanada; Koichiro Ikuta; Yuri Okimoto; Akira Ohara; Yohji Ohkawa; Taijiroh Mori; Kohichi Ishimoto; Takeyuki Sato; Takashi Kaneko; Miho Maeda; Kenichi Koike; Toshiji Shitara; Yasutaka Hoshi; Ryohta Hosoya; Yukiko Tsunematsu; Fumio Bessho; Shinpei Nakazawa; Tomohiro Saito

PURPOSE We postulated that intensification of chemotherapy immediately after remission induction might reduce the leukemic cell burden sufficiently to allow an abbreviated period of antimetabolite therapy. PATIENTS AND METHODS Three hundred forty-seven children (ages 1 to 15 years) with previously untreated acute lymphoblastic leukemia (ALL) were enrolled onto the Tokyo L92-13 study, which excluded patients with mature B-cell ALL and patients less than 1 year old. One hundred twenty-four patients were classified as standard risk, 122 as high risk, and 101 as extremely high risk, according to age, peripheral-blood leukocyte count, selected genetic abnormalities, and immunophenotype. All subjects received four drugs for remission induction, followed by a risk-directed multidrug intensification phase and therapy for presymptomatic leukemia in the CNS. Maintenance chemotherapy with oral mercaptopurine and methotrexate was administered for 6 months, with all treatment stopped by 1 year after diagnosis. RESULTS The mean (+/- SD) event-free survival (EFS) and overall survival rates for all patients were 59.5% +/- 3.4% and 81.5% +/- 2.2%, respectively, at 5. 5 years after diagnosis. EFS rates by risk category were similar (60. 2% +/- 6.0% for standard risk, 57.7% +/- 5.6% for high risk, and 62. 5% +/- 5.7% for extremely high risk), whereas overall survival rates differed significantly (91.2% +/- 2.7%, 80.0% +/- 4.1%, and 72.1% +/- 4.5%, respectively, P <.0001 by the log-rank test). There were 107 relapses. Eighty-five (79.4%) of these 107 patients achieved second complete remissions, with subsequent EFS rates of 61.5% +/- 7. 9% (standard risk), 42.6% +/- 8.1% (high risk), and 9.6% +/- 6.4% (extremely high risk). Of the five risk factors analyzed, only the response to prednisolone monotherapy among extremely high-risk patients proved important. CONCLUSION Early treatment intensification did not compensate for a truncated phase of maintenance chemotherapy in children with standard- or high-risk ALL. However, 6 months of antimetabolite treatment seemed adequate for extremely high-risk patients who were good responders to prednisolone and received intensified chemotherapy that included high-dose cytarabine early in the clinical course.


Leukemia | 2000

Long-term follow-up of childhood acute lymphoblastic leukemia in Tokyo Children's Cancer Study Group 1981-1995.

Masahiro Tsuchida; Koichiro Ikuta; Ryouji Hanada; Saito T; Keiichi Isoyama; Kenichi Sugita; Toyoda Y; Atsushi Manabe; Kazutoshi Koike; Akitoshi Kinoshita; Miho Maeda; Ishimoto K; Sato T; Yuri Okimoto; Kaneko T; Michiko Kajiwara; Manabu Sotomatsu; Yasuhide Hayashi; Hiromasa Yabe; Ryota Hosoya; Yasutaka Hoshi; Ohira M; Fumio Bessho; Tsunematsu Y; Ichiro Tsukimoto; Shinpei Nakazawa

The objectives were as follows: Firstly, to estimate the overall probability of event-free survival (EFS) and isolated CNS relapse in the studies for children with acute lymphoblastic leukemia (ALL) during the 1980s and 1990s. Secondly, to report the EFS according to presenting features and lineage. Thirdly, to evaluate the treatment results re-classified by the risks of NCI criteria. Four consecutive protocol studies were performed in the Tokyo Childrens Cancer Study Group: L81–10 protocol (1981–1984, 189 patients), L84–11 (1984–1989, 484 patents), L89–12 (1989–1992, 418 patients) and L92–13 (1992–1995, 347 patients). Overall EFS at 5 years in each protocol was 56.5 ± 3.8(1 s.e.)%, 71.0 ± 2.1%, 67.8 ± 2.3%, and 63.4 ± 2.7%, respectively. The cumulative isolated CNS relapse rate at 5 years was 8.1 ± 2.1%, 3.5 ± 0.9%, 3.6 ± 1.0%, 1.0 ± 0.6. The EFS in SR/HR (standard risk/high risk) according to the NCI criteria in B-precursor ALL at 5 years was 61.9 ± 4.3%/41.4 ± 7.4% (lineage was not confirmed.), 72.5 ± 2.6%/63.4 ± 5.0%, 77.4 ± 2.7%/56.3 ± 4.7%, and 67.8 ± 3.4%/56.7 ± 5.4% in each protocol. Also EFSs according to NCI SR/HR at 5 years of T-ALL in protocols L84–11, L89–12 and L92–13 were 55.6 ± 16.6%/60.9 ± 10.1%, 72.7 ± 13.4%/51.6 ± 9.1%, and 77.1 ± 14.4%/53.6/10.1%, respectively. The truncation of maintenance therapy to 6 months resulted in a decreased EFS in L92–13, particularly due to an increase of bone marrow relapse after cessation of therapy in SR and HR. The NCI risk criteria work properly even in the patients treated by different intensities, so that it makes the comparison possible among the patients in various groups. The overall EFSs in childhood ALL improved in 1980s, but it seemed stable or decreased in 1990s. The short maintenance therapy resulted in poor outcome in SR on the L92–13 protocol. Many of these late relapsers were effectively rescued and overall survival remained at a high level. The proportion of patients who received cranial irradiation reduced without any increase of the CNS events.


FEBS Letters | 1999

Characterization of GFR, a novel guanine nucleotide exchange factor for Rap1

Tamotsu Ichiba; Yasutaka Hoshi; Yoshikatsu Eto; Naoko Tajima; Yasunobu Kuraishi

Three groups of Rap1‐specific guanine nucleotide exchange factors including C3G, CalDAG‐GEFI, and Epac/cAMP‐GEFI/II have been identified to date. In the present study, we report a new Rap1 guanine nucleotide exchange factor which we have named GFR ( uanine nucleotide exchange actor for ap1). GFR shows close sequence similarity to EPAC/cAMP‐GEFI/II although GFR lacks a cAMP binding domain and contains a nuclear localization signal. We demonstrated that GFR can activate Rap1 but not H‐Ras in 293T cells and that the cdc25 domain of GFR is required for the activation of Rap1. Northern blot analysis suggested that GFR mRNA is strongly expressed in the brain. In transfected HeLa cells, GFR has been found to be localized in the nuclei.


Cancer | 1991

Effectiveness of high-dose MCNU therapy and hematopoietic stem cell autografts treatment of childhood acute leukemia/lymphoma with high-risk features.

Yoichi Takaue; Tsutomu Watanabe; Yasutaka Hoshi; Takanori Abe; Keiko Matsunaga; Saito S; Atsushi Hirao; Yoshifumi Kawano; Tsuneo Ninomiya; Yasuhiro Kuroda; Tetsuya Koyama; Takeshi Suzue; Tatsuo Shimokawa; Hiroshi Uchiyama; Arata Watanabe; Takeji Matsushita; Atsushi Kikuta; Ayako Yokobayashi; Ryusuke Murakami; Atsushi Manabe; Ryota Hosoya; Mutsuro Ohira; Takeo Fujimoto

Clinical and pharmacokinetic studies were performed regarding the toxicity of methyl 6‐[3‐(2‐chloroethyl)‐3‐nitrosoureido]‐6‐deoxy‐α‐D‐glucopyranoside (MCNU) with other drugs, in conjunction with a peripheral blood stem cell autograft (PBSCT), for treating 26 children with acute leukemia or lymphoma associated with high‐risk features. In the early phase of the study, MCNU (300 to 500 mg/m2) was administered with cytosine arabinoside (Ara‐C) (1.6 to 16 g/m2),etoposide (VP‐16) (0.8 to 1.6 g/m2), cyclophosphamide (CY) (100 to 200 mg/kg), or busulfan (16 mg/kg). No acute toxicity was noticed after this high‐dose therapy. The dose‐limiting factor of the regimens was significant but reversible interstitial pneumonitis (IP). In a subsequent trial with an MCNU/VP‐16/Ara‐C/CY (MCVAC) regimen in which the dose of MCNU was reduced, the risk of IP diminished. This study is still in progress, but the clinical response has so far been encouraging. Fifteen of 26 children are alive and well in unmaintained complete remission (CR) with a median follow‐up period of 11 months (range, 3 to 34 months) after transplantation.


Journal of Clinical Oncology | 2001

Delay of the diagnostic lumbar puncture and intrathecal chemotherapy in children with acute lymphoblastic leukemia who undergo routine corticosteroid testing: Tokyo Children's Cancer Study Group study L89-12.

Atsushi Manabe; Masahiro Tsuchida; Ryoji Hanada; Kouichiro Ikuta; Yasunori Toyoda; Yuri Okimoto; K. Ishimoto; H. Okawa; Akira Ohara; Takashi Kaneko; Kazutoshi Koike; Takeyuki Sato; Kenichi Sugita; Fumio Bessho; Yasutaka Hoshi; Miho Maeda; Akitoshi Kinoshita; Tomohiro Saito; Yukiko Tsunematsu; Shinpei Nakazawa

PURPOSE To determine the effects of eliminating initial lumbar punctures in 418 consecutively treated children with acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS Patients were enrolled onto a trial conducted in central Japan between 1989 and 1992. Treatment consisted of standard four-drug induction therapy followed by a risk-based intensification phase, reinduction therapy, late intensification, and remission maintenance therapy (total of 104 weeks). The initial lumbar puncture, with an intrathecal injection of chemotherapy, was performed after 1 week of prednisolone sensitivity testing (day 8). End points included response to prednisolone, CNS status at the time of the day 8 lumbar puncture, subsequent adverse events in CNS and bone marrow, and event-free survival (EFS). RESULTS The remission induction rate was 93.1% with a 6-year EFS rate (+/- SE) of 68.7% +/- 2.4%, which is similar to historical results for patients who received their diagnostic lumbar puncture and first instillation of intrathecal chemotherapy on day 0. Overall, 84.5% of the patients had good responses to prednisolone, whereas 15.5% had poor responses. Clinical outcome was strikingly better for the good responders (6-year EFS, 74.1% +/- 2.5% compared with 40.1% +/- 6.4% for patients with poor responses), suggesting that omission of intrathecal chemotherapy did not alter the predictive value of drug sensitivity testing. Eighteen patients experienced CNS relapse as their first adverse event (cumulative risk, 5.1%; 95% confidence interval, 2.7% to 7.4%), coincident with reports from groups using conventional strategies of CNS clinical management. Bleeding into the CSF at the time of the day 8 lumbar puncture was apparent in 29 cases (8.1%), but leukemic blasts were identified in only two. CONCLUSION Delay of the initial lumbar puncture and intrathecal injection of chemotherapy seems to be feasible in children with ALL. Further controlled evaluations are needed to establish the validity of this conclusion.


Pediatrics International | 2005

Allogenic bone marrow transplantation for late-infantile neuronal ceroid lipofuscinosis

Yuki Yuza; Kentaro Yokoi; Ken Sakurai; Masamichi Ariga; Takaaki Yanagisawa; Toya Ohashi; Yasutaka Hoshi; Yoshikatsu Eto

Late-infantile neuronal ceroid lipofuscinosis (NCL2; 204500) is a rare progressive neurodegenerative disorder with an autosomal recessive inheritance. NCL2 shows progressive myoclonic epilepsy and neurological deterioration with an onset usually between 2 and 4 years of age. The progressive loss of neurological function leads to premature death in the first or second decade of life. The gene responsible for classic NCL2, CLN2 , has been mapped to 11p15 1 and deficiency of CLN2 gene product, tripeptidyl peptidase-1 (TPP-1; E.C. 3.4.14.9), is considered to be the cause of this disease. 2–4 However, there are at least three other genetic variations within NCL2. Biochemically, NCL2 is divided into two categories based on the presence of TPP-1 activity. Currently there are no direct therapies other than supportive therapies reported. Bone marrow transplantation (BMT) as therapy has been previously reported. 5,6 Although there was engraftment failure, they reported retarded disease progression.


Transfusion and Apheresis Science | 2013

Online reporting system for transfusion-related adverse events to enhance recipient haemovigilance in Japan: A pilot study

Chikako Odaka; Hidefumi Kato; Hiroko Otsubo; Shigeru Takamoto; Yoshiaki Okada; Maiko Taneichi; Kazu Okuma; Kimitaka Sagawa; Yasutaka Hoshi; Tetsunori Tasaki; Yasuhiko Fujii; Yuji Yonemura; Noriaki Iwao; Asashi Tanaka; Hitoshi Okazaki; Shun Ya Momose; Junichi Kitazawa; Hiroshi Mori; Akio Matsushita; Hisako Nomura; Hitoshi Yasoshima; Yasushi Ohkusa; Kazunari Yamaguchi; Isao Hamaguchi

BACKGROUND A surveillance system for transfusion-related adverse reactions and infectious diseases in Japan was started at a national level in 1993, but current reporting of events in recipients is performed on a voluntary basis. A reporting system which can collect information on all transfusion-related events in recipients is required in Japan. METHODS We have developed an online reporting system for transfusion-related events and performed a pilot study in 12 hospitals from 2007 to 2010. RESULTS The overall incidence of adverse events per transfusion bag was 1.47%. Platelet concentrates gave rise to statistically more adverse events (4.16%) than red blood cells (0.66%) and fresh-frozen plasma (0.93%). In addition, we found that the incidence of adverse events varied between hospitals according to their size and patient characteristics. CONCLUSION This online reporting system is useful for collection and analysis of actual adverse events in recipients of blood transfusions and may contribute to enhancement of the existing surveillance system for recipients in Japan.


Vox Sanguinis | 2009

Consecutive national surveys of ABO-incompatible blood transfusion in Japan.

Yasuhiko Fujii; Y. Shibata; S. Miyata; S. Inaba; T. Asai; Yasutaka Hoshi; Junki Takamatsu; Koki Takahashi; Hitoshi Ohto; Takeo Juji; Kimitaka Sagawa

Background and Objectives  Morbidity and mortality from ABO‐incompatible transfusion persist as consequences of human error. Even so, insufficient attention has been given to improving transfusion safety within the hospital.


Leukemia | 1997

Role of CDK4 and p16INK4A in interleukin-6-mediated growth of multiple myeloma.

Mitsuyoshi Urashima; Gerrard Teoh; Atsushi Ogata; Dharminder Chauhan; Steven P. Treon; Yasutaka Hoshi; James A. DeCaprio; Kenneth C. Anderson

Interleukin-6 (IL-6) promotes growth of human multiple myeloma (MM) cells via phosphorylation of retinoblastoma protein (pRB). We therefore examined the kinetics of cyclin-dependent kinase 4 (CDK4), p16INK4A, and pRB activation during IL-6-mediated patient MM cell growth compared with growth of IL-6 unresponsive patient plasma cell leukemia (PCL) cells. CDK4 protein was more strongly expressed in PCL cells than in MM cells. On the other hand, p16 protein was present in MM cells but undetectable in PCL cells. Interestingly, IL-6 induced peak proliferation of MM cells at days 1–3, with a return to baseline levels of DNA synthesis by days 6–9 in spite of replenishing IL-6. In these cells, IL-6 triggered a sustained increase in CDK4 by day 1 and a gradual increase in p16 to day 9. The progressive increase in p16 without further increments in CDK4 resulted in a shift from cyclin D2–CDK4/CDK6 binding at days 1–3 to p16–CDK4/CDK6 complex formation at days 6–9. Both phosphorylated pRB and dephosphorylated pRB were present initially in patient MM cells; IL-6 triggered a shift to phosphorylated pRB and G1 to S transition at days 1–3, with return to baseline levels of dephosphorylated pRB and related G1 growth arrest by day 9. No similar changes in CDK4, p16, or cell cycle profile were observed in IL-6 nonresponsive PCL cells. Our data therefore suggest a feedback mechanism in IL-6-mediated MM cell growth which is absent in IL-6 nonresponsive PCL cells.

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Mitsuyoshi Urashima

Jikei University School of Medicine

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Akatsuka J

Jikei University School of Medicine

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Kihei Maekawa

Jikei University School of Medicine

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Kenneth C. Anderson

Memorial Sloan Kettering Cancer Center

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Hiroko Otsubo

Jikei University School of Medicine

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Hiroshi Uchiyama

Jikei University School of Medicine

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Yoko Kato

Jikei University School of Medicine

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