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Dive into the research topics where Akiyoshi Takami is active.

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Featured researches published by Akiyoshi Takami.


PLOS ONE | 2011

A genetic variant in the IL-17 promoter is functionally associated with acute graft-versus-host disease after unrelated bone marrow transplantation.

J. Luis Espinoza; Akiyoshi Takami; Katsuya Nakata; Makoto Onizuka; Takakazu Kawase; Hideki Akiyama; Koichi Miyamura; Yasuo Morishima; Yoshihisa Kodera; Shinji Nakao

Interleukin IL-17 is a proinflammatory cytokine that has been implicated in the pathogenesis of various autoimmune diseases. The single nucleotide polymorphism (SNP), rs2275913, in the promoter region of the IL-17 gene is associated with susceptibility to ulcerative colitis. When we examined the impact of rs2275913 in a cohort consisting of 438 pairs of patients and their unrelated donors transplanted through the Japan Marrow Donor Program, the donor IL-17 197A allele was found to be associated with a higher risk of acute graft-versus-host disease (GVHD; hazard ratio [HR], 1.46; 95% confidence interval [CI], 1.00 to 2.13; Pu200a=u200a0.05). Next, we investigated the functional relevance of the rs2275913 SNP. In vitro stimulated T cells from healthy individuals possessing the 197A allele produced significantly more IL-17 than those without the 197A allele. In a gene reporter assay, the 197A allele construct induced higher luciferase activity than the 197G allele, and the difference was higher in the presence of T cell receptor activation and was abrogated by cyclosporine treatment. Moreover, the 197A allele displayed a higher affinity for the nuclear factor activated T cells (NFAT), a critical transcription factor involved in IL-17 regulation. These findings substantiate the functional relevance of the rs2275913 polymorphism and indicate that the higher IL-17 secretion by individuals with the 197A allele likely accounts for their increased risk for acute GVHD and certain autoimmune diseases.


PLOS ONE | 2013

Resveratrol induces cell cycle arrest and apoptosis in malignant NK cells via JAK2/STAT3 pathway inhibition.

Ly Quoc Trung; J. Luis Espinoza; Akiyoshi Takami; Shinji Nakao

Natural killer (NK) cell malignancies, particularly aggressive NK cell leukaemias and lymphomas, have poor prognoses. Although recent regimens with L-asparaginase substantially improved outcomes, novel therapeutic approaches are still needed to enhance clinical response. Resveratrol, a naturally occurring polyphenol, has been extensively studied for its anti-inflammatory, cardioprotective and anti-cancer activities. In this study, we investigated the potential anti-tumour activities of resveratrol against the NK cell lines KHYG-1, NKL, NK-92 and NK-YS. Resveratrol induced robust G0/G1 cell cycle arrest, significantly suppressed cell proliferation and induced apoptosis in a dose- and time-dependent manner for all four cell lines. In addition, resveratrol suppressed constitutively active STAT3 in all the cell lines and inhibited JAK2 phosphorylation but had no effect on other upstream mediators of STAT3 activation, such as PTEN, TYK2, and JAK1. Resveratrol also induced downregulation of the anti-apoptotic proteins MCL1 and survivin, two downstream effectors of the STAT3 pathway. Finally, resveratrol induced synergistic effect on the apoptotic and antiproliferative activities of L-asparaginase against KHYG-1, NKL and NK-92 cells. These results suggest that resveratrol may have therapeutic potential against NK cell malignancies. Furthermore, our finding that resveratrol is a bonafide JAK2 inhibitor extends its potential benefits to other diseases with dysregulated JAK2 signaling.


British Journal of Haematology | 2009

Origin and fate of blood cells deficient in glycosylphosphatidylinositol‐anchored protein among patients with bone marrow failure

Chiharu Sugimori; Kanako Mochizuki; Zhirong Qi; Naomi Sugimori; Ken Ishiyama; Yukio Kondo; Hirohito Yamazaki; Akiyoshi Takami; Hirokazu Okumura; Shinji Nakao

Peripheral blood from 489 recently diagnosed patients with aplastic anaemia (AA) and 316 with refractory anaemia (RA) of myelodysplastic syndrome was evaluated to characterize CD55−CD59− [paroxysmal nocturnal haemoglobinuria (PNH)]‐type blood cells associated with bone marrow (BM) failure. PNH‐type cells were detected in 57% and 20% of patients with AA and RA, respectively. The percentages of PNH‐type granulocytes ranged from 0·003% to 94·2% and the distribution was log‐normal with a median of 0·178%. Serial analyses of 75 patients with PNH‐type cells over 5u2003years revealed that the percentage of PNH‐type cells constantly increased in 13 (17%), persisted in 44 (59%), disappeared in the remaining 18 (24%) although even in the ‘Disappearance’ group, PNH‐type granulocytes persisted for at least 6u2003months. A scattergram profile of PNH‐type cells unique to each patient persisted regardless of the response to immunosuppressive therapy and only single PIGA mutations were detected in PNH‐type granulocytes sorted from four patients. These findings suggest that the PNH‐type cells in patients with BM failure are derived from single PIGA mutant haematopoietic stem cells even when their percentages are <1% and their fate depends on the proliferation and self‐maintenance properties of the individual PIGA mutants.


Haematologica | 2009

NKG2D gene polymorphism has a significant impact on transplant outcomes after HLA-fully-matched unrelated bone marrow transplantation for standard risk hematologic malignancies

J. Luis Espinoza; Akiyoshi Takami; Makoto Onizuka; Hiroshi Sao; Hideki Akiyama; Koichi Miyamura; Shinichiro Okamoto; Masami Inoue; Yoshinobu Kanda; Shigeki Ohtake; Yasuo Morishima; Yoshihisa Kodera; Shinji Nakao

NKG2D is an activating and co-stimulatory receptor expressed on natural killer cells and T cells that confers multiple effects in the immune control of microbial infections and malignant disease. As a result, donor and recipient polymorphisms in the NKG2D gene may have an effect on the outcome of allogeneic hematopoietic stem cell transplantations (HSCT). In this study, Dr. Espinoza and colleagues found that the donor NKG2D-HNK1 haplotype was linked to improved overall survival and impaired transplant-related mortality after unrelated, myeloablative conditioned HSCT of patients suffering from hematologic malignancies and reported to the Japan Marrow Donor Program. Background NKG2D, an activating and co-stimulatory receptor expressed on natural killer cells and T cells, plays pivotal roles in immunity to microbial infections as well as in cancer immunosurveillance. This study examined the impact of donor and recipient polymorphisms in the NKG2D gene on the clinical outcomes of patients undergoing allogeneic T-cell-replete myeloablative bone marrow transplantation using an HLA-matched unrelated donor. Design and Methods The NKG2D polymorphism was retrospectively analyzed in a total 145 recipients with hematologic malignancies and their unrelated donors. The patients underwent transplantation following myeloablative conditioning; the recipients and donors were matched through the Japan Marrow Donor Program. Results In patients with standard-risk disease, the donor NKG2D-HNK1 haplotype, a haplotype expected to induce greater natural killer cell activity, was associated with significantly improved overall survival (adjusted hazard ratio, 0.44; 95% confidence interval, 0.23 to 0.85; p=0.01) as well as transplant related mortality (adjusted hazard ratio, 0.42; 95% confidence interval, 0.21 to 0.86; p=0.02), but had no impact on disease relapse or the development of grade II–IV acute graft-versus-host disease or chronic graft-versus-host disease. The NKG2D polymorphism did not significantly influence the transplant outcomes in patients with high-risk disease. Conclusions These data suggest an association between the donor HNK1 haplotype and better clinical outcome among recipients, with standard-risk disease, of bone marrow transplants from HLA-matched unrelated donors.


Biology of Blood and Marrow Transplantation | 2014

Donor Lymphocyte Infusion for the Treatment of Relapsed Acute Myeloid Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation: A Retrospective Analysis by the Adult Acute Myeloid Leukemia Working Group of the Japan Society for Hematopoietic Cell Transplantation

Akiyoshi Takami; Shingo Yano; Hiroki Yokoyama; Yachiyo Kuwatsuka; Takuhiro Yamaguchi; Yoshinobu Kanda; Yasuo Morishima; Yasushi Miyazaki; Hirohisa Nakamae; Junji Tanaka; Yoshiko Atsuta; Heiwa Kanamori

Because the efficacy of donor lymphocyte infusion (DLI) for acute myeloid leukemia (AML) relapse after allogeneic hematopoietic stem cell transplantation (HSCT) remains uncertain, especially in the Asian population, a nationwide registry study was retrospectively performed by the Adult AML Working Group of the Japan Society for Hematopoietic Cell Transplantation to identify the factors affecting the patient survival after DLI. Among 143 adult AML patients who received DLI for the treatment of first hematological relapse after HSCT, the overall survival rates at 1 year, 2 years, and 5 years were 32% ± 4%, 17% ± 3%, and 7% ± 3%, respectively. Complete remission (CR) at the time of DLI, which was obtained in 8% of the patients, was the strongest predictive factor for survival after DLI. Therefore, long-term survival after DLI was achieved almost exclusively in patients who successfully achieved a CR before DLI, indicating the limited efficacy of DLI in a minority of patients.


Transplant Infectious Disease | 2012

Safety of pre-engraftment prophylactic foscarnet administration after allogeneic stem cell transplantation

Ken Ishiyama; Takamasa Katagiri; Kinya Ohata; Kohei Hosokawa; Yukio Kondo; Hirohito Yamazaki; Akiyoshi Takami; Shinji Nakao

K. Ishiyama, T. Katagiri, K. Ohata, K. Hosokawa, Y. Kondo, H. Yamazaki, A. Takami, S. Nakao. Safety of pre‐engraftment prophylactic foscarnet administration after allogeneic stem cell transplantation. Transpl Infect Dis 2011. All rights reserved


Annals of Hematology | 2011

Efficacy and safety of micafungin as an empirical therapy for invasive fungal infections in patients with hematologic disorders: a multicenter, prospective study

Masaki Yamaguchi; Toshiro Kurokawa; Ken Ishiyama; Go Aoki; Mikio Ueda; Sadaya Matano; Akiyoshi Takami; Hirohito Yamazaki; Aiko Sawazaki; Hiromasa Yamauchi; Takashi Yoshida; Shinji Nakao

This study was conducted as a prospective, multicenter trial to evaluate the efficacy and safety of micafungin as an empirical therapy for suspected invasive fungal infections (IFIs), including febrile neutropenia (FN), and to evaluate the usefulness of β-d-glucan (BG) and Aspergillus galactomannan (GM) antigen in patients with hematologic diseases. A total of 121 patients were enrolled and assessed for safety, and 119 were examined for clinical efficacy. The main underlying diseases were acute myeloid leukemia (38.0%), acute lymphoblastic leukemia (18.2%), and malignant lymphoma (18.2%). The median initial daily dose and duration of micafungin treatment were 150xa0mg/day and 13xa0days, respectively. The overall response rate for suspected IFIs (nu2009=u2009119), based on four composite endpoints, including baseline IFI, breakthrough IFIs (proven and probable), survival, and premature discontinuation, was 79.0%. In addition, the response rate for FN (nu2009=u200981), based on these four endpoints as well as defervescence during neutropenia, was 39.5%. Breakthrough IFIs (proven, probable, and possible) occurred in five patients during micafungin treatment. All of these patients were positive for either BG or GM before the breakthrough IFIs. The incidence of adverse events (AEs) associated with micafungin was 10.7% and most were mild. The majority of AEs were liver dysfunction. These results indicate the effectiveness and safety of micafungin as an empirical therapy for suspected IFIs, including FN, and the usefulness of monitoring both BG and GM to detect breakthrough IFIs.


Bone Marrow Transplantation | 2011

A single nucleotide polymorphism of IL-17 gene in the recipient is associated with acute GVHD after HLA-matched unrelated BMT

J. L. Espinoza; Akiyoshi Takami; Makoto Onizuka; Takakazu Kawase; Hiroshi Sao; Hideki Akiyama; Koichi Miyamura; Shinichiro Okamoto; Masami Inoue; Shigeki Ohtake; Yasuo Morishima; Yoshihisa Kodera; Shinji Nakao

IL-17 has an important role in the host defense against extracellular pathogens and the pathophysiology of autoimmune diseases. This study retrospectively examined the impact of a single-nucleotide polymorphism (rs2275913, G197A) in the IL-17 gene of a total 510 recipients with hematologic malignancies and their unrelated donors on the clinical outcomes in HLA-matched myeloablative (discovery study) and nonmyeloablative (validation study) BMT through the Japan Marrow Donor Program (JMDP). In the discovery study, the presence of a 197A genotype in the recipient resulted in a higher incidence of grades II–IV acute GVHD (hazard ratio (HR), 1.87; 95% confidence interval (CI), 1.23–2.85; P=0.004). The donor IL-17A genotype did not significantly influence the transplant outcomes. The validation study showed a trend toward an association of the recipient 197A genotype with an increased risk of grades III–IV acute GVHD (HR, 5.84; 95% CI, 0.75–45.72; P=0.09), as well as a significantly increased risk for chronic GVHD (HR, 3.86; 95% CI, 1.29–11.59; P=0.02). These results suggest an association of the 197A genotype in the recipient side with the development of acute GVHD.


American Journal of Hematology | 2016

Impact of age on outcomes of allogeneic hematopoietic stem cell transplantation with reduced intensity conditioning in elderly patients with acute myeloid leukemia.

Jun Aoki; Heiwa Kanamori; Masatsugu Tanaka; Satoshi Yamasaki; Hiroyasu Ogawa; Koji Iwato; Kazuteru Ohashi; Hirokazu Okumura; Makoto Onizuka; Yoshitomo Maesako; Takanori Teshima; Naoki Kobayashi; Yasuo Morishima; Makoto Hirokawa; Yoshiko Atsuta; Shingo Yano; Akiyoshi Takami

Previous studies have repeatedly reported that increasing age is a significant risk factor for worse outcomes after allogeneic hematopoietic stem cell transplantation (allo‐HSCT) among patients with acute myeloid leukemia (AML). However, more recent studies reported conflicting results regarding the association between age and outcomes in elderly patients. Therefore, we conducted a large‐scale, nationwide retrospective study to examine the impact of age on outcomes of allo‐HSCT with reduced intensity conditioning (RIC) for AML patients who were older than 50 years. Of the 757 patients, 89 patients (11.8%) were 50–54, 249 patients (32.9%) were 55–59, 301 patients (39.8%) were 60–64 and 118 patients (15.6%) were ≥65 years old. The 3‐year overall survival (OS) (47.8, 45.2, 37.9, and 36.6% for patients aged 50–54, 55–59, 60–64, and ≥65 years, respectively, Pu2009=u20090.24) and nonrelapse mortality (NRM) (24.0, 22.8, 29.2, and 27.6% for patients aged 50–54, 55–59, 60–64, and ≥65 years, respectively, Pu2009=u20090.49) were not significantly different among the four age groups. Multivariate analysis revealed that increased age had no significant effect on OS or NRM after adjusting for covariates. These results suggested that advanced patient age is not a contraindication for RIC allo‐HSCT in elderly AML patients. Am. J. Hematol. 91:302–307, 2016.


Biology of Blood and Marrow Transplantation | 2014

Outcome of Allogeneic Hematopoietic Stem Cell Transplantation for Acute Myeloid Leukemia Patients with Central Nervous System Involvement

Jun Aoki; Ken Ishiyama; Shuichi Taniguchi; Kazuteru Ohashi; Hiroyasu Ogawa; Heiwa Kanamori; Tetsuya Eto; Koji Iwato; Hisashi Sakamaki; Yasuo Morishima; Tokiko Nagamura; Yoshiko Atsuta; Akiyoshi Takami

Central nervous system (CNS) involvement in adult acute myeloid leukemia (AML) is rare and associated with poor outcomes. Therefore, CNS involvement in AML is an indicator for allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the impact of CNS involvement in AML on the outcome of allo-HSCT remains unclear. We performed a large-scale nationwide retrospective analysis to elucidate the outcomes of allo-HSCT on AML with CNS involvement (CNS+AML). Clinical data were collected from a registry database of the Japan Society for Hematopoietic Cell Transplantation. CNS involvement was defined as the infiltration of leukemia cells into the CNS or myeloid sarcoma in the CNS identified at any time from diagnosis to transplantation. One hundred fifty-seven patients with CNS+AML underwent allo-HSCT between 2006 and 2011. The estimated overall survival, cumulative incidence of relapse and nonrelapse mortality at 2 years for CNS+AML (51.2%, 30.2%, and 14.5%, respectively) were comparable with those for AML without CNS involvement (48.6%, 27.4%, and 22.0%, respectively). Univariate and multivariate analyses indicated that the development of chronic graft-versus-host disease, disease status, and cytogenetic risk category were independent prognostic factors for overall survival for CNS+AML. These results suggest that allo-HSCT may improve outcomes in patients with CNS+AML.

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Yasuo Morishima

Gulf Coast Regional Blood Center

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Heiwa Kanamori

Yokohama City University

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