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Dive into the research topics where Masaharu Kasai is active.

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Featured researches published by Masaharu Kasai.


Blood | 2009

Disease-specific analyses of unrelated cord blood transplantation compared with unrelated bone marrow transplantation in adult patients with acute leukemia

Yoshiko Atsuta; Ritsuro Suzuki; Tokiko Nagamura-Inoue; Shuichi Taniguchi; Satoshi Takahashi; Shunro Kai; Hisashi Sakamaki; Yasushi Kouzai; Masaharu Kasai; Hiroshi Azuma; Minoko Takanashi; Shinichiro Okamoto; Masahiro Tsuchida; Keisei Kawa; Yasuo Morishima; Yoshihisa Kodera; Shunichi Kato

We made a disease-specific comparison of unrelated cord blood (CB) recipients and human leukocyte antigen allele-matched unrelated bone marrow (BM) recipients among 484 patients with acute myeloid leukemia (AML; 173 CB and 311 BM) and 336 patients with acute lymphoblastic leukemia (ALL; 114 CB and 222 BM) who received myeloablative transplantations. In multivariate analyses, among AML cases, lower overall survival (hazard ratio [HR]=1.5; 95% confidence interval [CI], 1.0-2.0, P= .028) and leukemia-free survival (HR=1.5; 95% CI, 1.1-2.0, P= .012) were observed in CB recipients. The relapse rate did not differ between the 2 groups of AML (HR=1.2; 95% CI, 0.8-1.9, P= .38); however, the treatment-related mortality rate showed higher trend in CB recipients (HR=1.5; 95% CI, 1.0-2.3, P= .085). In ALL, there was no significant difference between the groups for relapse (HR=1.4, 95% CI, 0.8-2.4, P= .19) and treatment-related mortality (HR=1.0; 95% CI, 0.6-1.7, P= .98), which contributed to similar overall survival (HR=1.1; 95% CI, 0.7-1.6, P= .78) and leukemia-free survival (HR=1.2; 95% CI, 0.9-1.8, P= .28). Matched or mismatched single-unit CB is a favorable alternative stem cell source for patients without a human leukocyte antigen-matched related or unrelated donor. For patients with AML, decreasing mortality, especially in the early phase of transplantation, is required to improve the outcome for CB recipients.


Transfusion | 2009

Reduction in adverse reactions to platelets by the removal of plasma supernatant and resuspension in a new additive solution (M-sol).

Hiroshi Azuma; Junichi Hirayama; Mitsuaki Akino; Reiko Miura; Yoshio Kiyama; Kiyotoshi Imai; Masaharu Kasai; Kazuki Koizumi; Yasutaka Kakinoki; Yusuke Makiguchi; Koji Kubo; Yoshiko Atsuta; Mitsuhiro Fujihara; Chihiro Homma; Sadamitsu Yamamoto; Toshiaki Kato; Hisami Ikeda

BACKGROUND: Leukodepletion reduces but does not eliminate adverse reactions to platelet concentrate (PC). As an alternative strategy, plasma reduction or washing of platelets should be considered. However, the efficacy of this strategy is still unclear.


Leukemia | 2005

Value of chemotherapy before allogeneic hematopoietic stem cell transplantation from an HLA-identical sibling donor for myelodysplastic syndrome

K. Nakai; Yoshinobu Kanda; Shirou Fukuhara; Hisashi Sakamaki; Shinichiro Okamoto; Yasuhiro Kodera; Ryuji Tanosaki; Satoshi Takahashi; Takafumi Matsushima; Yoshiko Atsuta; Nobuyuki Hamajima; Masaharu Kasai; Shunichi Kato

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is a curative treatment for myelodysplastic syndrome (MDS). The object of this study was to evaluate the impact of chemotherapy before allo-SCT. We analyzed the data of 283 patients who underwent allo-SCT from an HLA-identical sibling donor for MDS that were reported to the Japan Society for Hematopoietic Cell Transplantation. The cumulative incidence of grade II–IV acute GVHD was 33%. Overall survival (OS) at 5 and 10 years was 48.8 and 42.5%, respectively. Multivariate analyses identified karyotype, FAB classification, and the history of chemotherapy before allo-SCT as significant predictors for OS. OS at 5 years was 57% for patients who underwent allo-SCT as a primary treatment for refractory anemia with excess blasts in transformation (RAEB-t) or secondary acute myeloid leukemia (AML) and 54% for those who underwent allo-SCT in remission after induction chemotherapy (P=0.81). The proportion of patients with a poor karyotype was equivalent between the two groups (P=0.44). Although only a randomized controlled trial will be able to establish a definite conclusion, these results do not support the administration of induction chemotherapy for patients with RAEB-t or secondary AML before allo-SCT.


Therapeutic Apheresis and Dialysis | 2005

Prevention of Limb Amputation in Patients with Limbs Ulcers by Autologous Peripheral Blood Mononuclear Cell Implantation

Akio Kawamura; Takashi Horie; Ichirou Tsuda; Atushi Ikeda; Hirotoshi Egawa; Emi Imamura; Junichi Iida; Hiromi Sakata; Tohru Tamaki; Kazutaka Kukita; Jun-ichi Meguro; Motoki Yonekawa; Masaharu Kasai

Abstract:  There are many cases of amputation of ischemic limbs of dialysis patients due to diabetes, despite the availability of medicine therapy and vascular by‐pass operations. As there is extensive ruin of the vascular bed due to diabetes, vascular regeneration therapy by stem cell implantation is effective. Thirty patients with ischemic limbs due to diabetes (not including type‐I) and on dialysis for chronic renal failure (19 cases), diabetes (5 cases), dialysis patients without diabetes (4 cases), and arteriosclerosis obliterans (ASO, 2 cases) were treated by autologous peripheral blood stem cell (PBSC) implantation where imminent amputation was under consideration. Granulocyte Colony Stimulate Factor (G‐CSF: 5 µg/kg/day) was administered subcutaneously for 4 days before PBSC collection, that was carried out using a centrifuge (Spectra and/or CS3000) via the vein. The collected PBSC, containing 4.2 × 107 of CD 34 positive cells, was divided into units of 0.5–1.0 mL and implanted, without any purification, to the ischemic area of the limbs in about 65 points. In 21 cases, normalization of limb temperature was observed by thermograph, and symptoms also improved. The result of this first attempt of PBSC implantation is that we were able to save 22 ischemic limbs. This is the first large report of the application of regenerative medicine to peripheral ischemic limbs.


British Journal of Haematology | 2003

Allogeneic haematopoietic stem cell transplantation for the treatment of adult T‐cell leukaemia/lymphoma

Masahiro Kami; Tamae Hamaki; Shigesaburo Miyakoshi; Naoko Murashige; Yoshinobu Kanda; Ryuji Tanosaki; Yoichi Takaue; Shuichi Taniguchi; Hisamaru Hirai; Keiya Ozawa; Masaharu Kasai

Summary. The feasibility of allogeneic haematopoietic stem‐cell transplantation (allo‐HSCT) in 11 patients with adult T‐cell leukaemia/lymphoma (ATL) (6 acute, 4 lymphoma, 1 chronic type) was evaluated. The preparative regimens (9 conventional, 2 reduced‐intensity) were tolerable. Five patients developed acute graft‐versus‐host disease (GVHD), and three, extensive chronic GVHD. All 10 patients who survived > 30 d achieved complete remission. Estimated 1‐year overall and disease‐free survival rates were 53 ± 30% and 45 ± 29% respectively. Four patients remain alive and disease‐free at a median follow‐up of 25 months. The others died of transplantation‐related complications. This pilot study suggests that allo‐HSCT in ATL should be evaluated further.


British Journal of Haematology | 2008

Cytokine gene expression in peripheral blood mononuclear cells during graft-versus-host disease after allogeneic bone marrow transplantation

Junji Tanaka; Masahiro Imamura; Masaharu Kasai; Nobuo Masauzi; Atsushi Matsuura; Hiroko Ohizumi; Ken Morii; Yoshio Kiyama; Tohru Naohara; Masao Saitho; Toshio Higa; Koichi Honke; Shinsei Gasa; Keisuke Sakurada; Tamotsu Miyazaki

Summary. Cytokine gene expression in peripheral blood mononuclear cells during the development of graft‐versus‐host disease (GVHD) in patients who underwent allogeneic bone marrow transplantation (allo BMT) was analysed using a semiquantitative reverse‐transcriptase polymerase chain reaction (RT‐PCR). The expression of interleukin (IL)‐lβ, IL‐6, and tumour necrosis factor (TNF)‐α mRNA was increased during the development of GVHD and the degree of this increment depended on the severity of the disease. IL‐2 expression was not detected at all and interferon‐γ expression was not much changed during GVHD. In patients with hepatic veno‐occlusive disease (VOD), another transplantation‐related complication, the expression of IL‐1β and TNF‐a mRNA was increased but IL‐6 mRNA expression showed little increase. These findings suggest that IL‐lβ, IL‐6 and TNF‐α produced by peripheral blood mononuclear cells play an important role in the development of GVHD. Furthermore, liver dysfunction due to GVHD or VOD may be distinguishable by this type of cytokine analysis. Analysis of cytokine mRNA expression in peripheral blood mononuclear cells after allogeneic bone marrow transplantation may provide important information concerning the immune response and the cytokine network system in marrow transplant patients.


International Journal of Hematology | 2003

Deoxycoformycin-containing combination chemotherapy for adult T-cell leukemia-lymphoma: Japan Clinical Oncology Group Study (JCOG9109).

Kunihiro Tsukasaki; Kensci Tobinai; Masanori Shimoyama; Mitsuo Kozuru; Naokuni Uikc; Yasuaki Yamada; Masao Tomonaga; Koichi Araki; Masaharu Kasai; Kiyoshi Takatsuki; Mitsutoshi Tara; Chikara Mikuni; Tomomitsu Hotta

Aggressive adult T-cell leukemia-lymphoma (ATL) generally has a very poor prognosis. Deoxycoformycin (DCF, pentostatin), an inhibitor of adenosine deaminase, has shown promising therapeutic efficacy for ATL. To develop a new effective therapy against aggressive ATI., we carried out a multicenter phase II study of DCF-containing combination chemotherapy. Sixty-two previously untreated patients with ATL (34, 21, and 7 patients with diseases of the acute, lymphoma, and unfavorable chronic types, respectively) were enrolled, but 2 were ineligible because they were judged to be favorable chronic types. A regimen of 1 mg/m2 vincristine intravenously on days 1 and 8, 40 mg/m2 doxorubicin intravenously on day 1,100 mg/m2 etoposide intravenously on days 1 through 3, 40 mg/m2 prednisolone orally on days 1 and 2, and 5 mg/m2 DCF intravenously on days 8,15, and 22 was administered every 28 days for 10 cycles unless disease progression or toxic complications occurred. Fifty-two percent of 60 eligible patients responded (95% confidence interval [CI], 38%-65%), with 17 patients (28%) achieving a complete response (CR) (95% CI, 17%-41%) and 14 achieving a partial response. The CR rate was inferior to those of both the previous Japan Clinical Oncology Group (JCOG) study (JCOG8701, 43%), a 9-drug combination chemotherapy of the second generation, and the subsequent JCOG9303 study (35%), a granulocyte colony-stimulating factor-supported, dose-intensified, 9-drug regimen. The median survival time of the 60 eligible patients in JCOG9109 was 7.4 months, and the estimated 2-year survival rate was 15.5%; these results were identical with those of JCOG8701 but inferior to those of JCOG9303. Grade 4 neutropenia and infection of grade 3 or greater were frequent (67% and 22%, respectively), and treatment-related death was observed in 4 patients (7%), scpticcmia in 2, and cytomcgalovirus pneumonia in 2. We conclude that DCF-containing combination chemotherapy is not a promising regimen against aggressive ATL.


Transfusion | 2003

Biologic activity of RANTES in apheresis PLT concentrates and its involvement in nonhemolytic transfusion reactions

Shinobu Wakamoto; Mitsuhiro Fujihara; Kazuhiro Kuzuma; Shinichiro Sato; Toshiaki Kato; Tohru Naohara; Masaharu Kasai; Ken-ichi Sawada; Ryoji Kobayashi; Tooru Kudoh; Kenji Ikebuchi; Hiroshi Azuma; Hisami Ikeda

BACKGROUND: RANTES, one of the PLT‐derived biologic response modifiers, accumulates in PLT concentrates (PCs) during storage and may play a causative role in nonhemolytic transfusion reactions (NHTRs) after PC transfusion.


Current Stem Cell Research & Therapy | 2009

Mesenchymal stem cells for treatment and prevention of graft-versus-host disease after allogeneic hematopoietic cell transplantation

Tomomi Toubai; Sophie Paczesny; Yusuke Shono; Junji Tanaka; Kathleen P. Lowler; Chelsea Malter; Masaharu Kasai; Masahiro Imamura

Allogeneic hematopoietic cell transplantation (allo-HCT) is an effective therapy for hematological malignancies and inherited diseases. However, acute graft-versus-host-disease (aGVHD) is a major life-threatening complication after allo-HCT and there are few therapeutic options for severe steroid-refractory aGVHD. Preliminary studies on co-transplantation of mesenchymal stem cells (MSCs) have shown an improvement in or resolution of severe aGVHD. However, the mechanism underlying this immunosuppressive effect has not been elucidated. Most of the data suggest that the immunosuppressive effect involves soluble factors such as IL-6 or TGF-beta as well as cell-cell contact dependence. MSCs interact either directly with T cells or indirectly via other immune cells such as dendritic cells and NK cells. Here we review the immunomodulatory function of MSCs in allo-HCT and their potential usefulness in the treatment or prevention of severe acute GVHD.


Biology of Blood and Marrow Transplantation | 2008

A Retrospective Analysis of Allogeneic Hematopoietic Stem Cell Transplantation for Adult T Cell Leukemia/Lymphoma (ATL): Clinical Impact of Graft-versus-Leukemia/Lymphoma Effect

Souichi Shiratori; Atsushi Yasumoto; Junji Tanaka; Akio Shigematsu; Satoshi Yamamoto; Mitsufumi Nishio; Satoshi Hashino; Rena Morita; Mutsumi Takahata; Masahiro Onozawa; Kaoru Kahata; Takeshi Kondo; Shuichi Ota; Kentaro Wakasa; Junichi Sugita; Takao Koike; Masahiro Asaka; Masaharu Kasai; Masahiro Imamura

Adult T cell leukemia/lymphoma (ATL) is a highly aggressive T cell malignancy, and has a poor prognosis. Recently, allogeneic-hematopoietic stem cell transplantation (allo-HSCT) has been suggested to improve the outcome. We retrospectively analyzed 15 patients with ATL who had received allo-HSCT in 2 institutions in Hokkaido, Japan. The median age of the patients was 57 years. The estimated 3-year overall survival (OS) and progression-free survival (PFS) rates were 73.3% and 66.7%, respectively. Calcineurin inhibitor dosage was reduced and administration was discontinued abruptly in 6 of the 15 patients for disease control; as a result, 4 (66.7%) of the 6 patients achieved complete response (CR) or partial response. Therefore, a graft-versus-leukemia/lymphoma (GVL) effect might be induced by discontinuation of immunosuppression. Thirteen of the 15 patients were followed up by monitoring HTLV-1 proviral DNA levels. In 10 of the 11 patients with positive HTLV-1 proviral DNA before allo-HSCT, HTLV-1 proviral DNA became undetectable at least once after allo-HSCT, and only 1 of the 5 patients in whom HTLV-1 proviral DNA became detectable after allo-HSCT relapsed. Compared to the results of past studies, these results show that allo-HSCT greatly improved the prognosis of ATL and suggest a contribution of the induction of a GVL effect.

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