研究者業績

山本 千裕

ヤマモト チヒロ  (Yamamoto Chihiro)

基本情報

所属
自治医科大学 医学部内科学講座 血液学部門 講師

通称等の別名
Sakurai Chihiro
J-GLOBAL ID
201501017106920717
researchmap会員ID
B000248147

論文

 67
  • Shoko Ito, Shin-ichiro Fujiwara, Kiyomi Mashima, Kento Umino, Daisuke Minakata, Hirofumi Nakano, Ryoko Yamasaki, Yasufumi Kawasaki, Miyuki Sugimoto, Masahiro Ashizawa, Chihiro Yamamoto, Kaoru Hatano, Kiyoshi Okazuka, Kazuya Sato, Iekuni Oh, Ken Ohmine, Takahiro Suzuki, Kazuo Muroi, Yoshinobu Kanda
    ANNALS OF HEMATOLOGY 96(5) 719-724 2017年5月  査読有り
    The development of acute myeloid leukemia (AML) in patients with untreated chronic lymphocytic leukemia (CLL) is rare. We experienced a 65-year-old man who developed AML with aberrant CD7 expression and monoallelic CEBPA mutation during watchful waiting for CLL. He failed to achieve complete response (CR) by standard induction therapy for AML. We retrospectively reviewed 27 patients who developed AML with untreated CLL published between 1973 and 2016. The median age at diagnosis of AML was 68 years, and the median duration between the diagnoses of AML and CLL was 4.2 years. Diagnosis of AML and CLL was made simultaneously in 16 patients. The CR rate of AML was 42.9%, and the median survival was only 1.5 months after the diagnosis of AML. Patients who achieved CR tended to survive longer than those who did not. Our results demonstrated that the development of AML in patients with untreated CLL was associated with a poor response to chemotherapy and an extremely poor prognosis.
  • Kento Umino, Shin-ichiro Fujiwara, Takashi Ikeda, Yumiko Toda, Shoko Ito, Kiyomi Mashima, Daisuke Minakata, Hirofumi Nakano, Ryoko Yamasaki, Yasufumi Kawasaki, Miyuki Sugimoto, Chihiro Yamamoto, Masahiro Ashizawa, Kaoru Hatano, Kazuya Sato, Iekuni Oh, Ken Ohmine, Kazuo Muroi, Yoshinobu Kanda
    HEMATOLOGY 22(9) 521-526 2017年  査読有り
    Objectives: Follicular lymphoma (FL) is a clinically and biologically heterogeneous disease. Therefore, it is important to identify factors that can predict its clinical outcome. Methods: We retrospectively evaluated the usefulness of soluble interleukin-2 receptor (sIL-2R) levels after R-CHOP (posttreatment sIL-2R) in 72 patients with newly diagnosed FL who had either a complete response (CR) or partial response. With the use of a recursive partitioning analysis, we determined the cut-off values of post- and pretreatment sIL-2R levels that were associated with disease progression, which corresponded to 486.5 and 5405U/mL, respectively. Results: The high posttreatment sIL-2R group showed a significantly inferior progression-free survival (PFS) compared to the low posttreatment sIL-2R group in all patients (3-year PFS 52.6% vs. 77.4%, P=0.003), and in patients with CR (3-year PFS 57.1% vs. 82.1%, P=0.034). Although a multivariate analysis showed that pretreatment sIL-2R, but not posttreatment sIL-2R, was an independently significant predictive factor for disease progression, among patients with low pretreatment sIL-2R levels, those with high posttreatment sIL-2R levels tended to have inferior PFS. There was a significant trend in PFS among the high pretreatment sIL-2R group, the low pre- and high posttreatment sIL-2R group, and the low pre- and low posttreatment sIL-2R group (P<0.001). Conclusion: Among patients with a low pretreatment sIL-2R level who exhibited a positive response to R-CHOP, the posttreatment sIL-2R level may help to identify those with a poor prognosis.
  • Kento Umino, Shin-ichiro Fujiwara, Kazuya Sato, Daisuke Minakata, Hirofumi Nakano, Ryoko Yamasaki, Yasufumi Kawasaki, Miyuki Sugimoto, Chihiro Yamamoto, Kaoru Hatano, Kiyoshi Okazuka, Lekuni Oh, Ken Ohmine, Takahiro Suzuki, Kazuo Muroi, Yoshinobu Kanda
    ACTA HAEMATOLOGICA 137(2) 93-99 2017年  査読有り
    The prognosis of patients with systemic lymphoma with central nervous system (CNS) involvement is very poor and there is no established standard therapy. We retrospectively analyzed 18 patients (4 untreated and 14 relapsed) with systemic lymphoma with CNS involvement who received methotrexate and cytarabine-based multiagent chemotherapy (modified Bonn protocol). Complete and partial responses were achieved in 56 and 22% of the patients, respectively. The 1-year overall survival (OS) and progression-free survival (PFS) was 81.0 and 39.2%, respectively. Patients with parenchymal involvement showed a better 1-year PFS than those with either leptomeningeal involvement or both. In a multivariate analysis, poor performance status (PS) was the only independent prognostic factor for the 1-year OS and PFS (HR 10.8, 95% CI 1.09-108, p = 0.042; HR 20.8, 95% CI 2.39-181, p = 0.006, respectively). Grade 4 neutropenia and thrombocytopenia occurred in 17 patients each (94%), but there were no grade 4 nonhematopoietic adverse events. The modified Bonn pro-tocol resulted in relatively favorable response and survival, and provided clinical benefits to patients with good PS, in particular. This study demonstrated that the modified Bonn protocol could be a feasible and encouraging treatment approach for lymphoma with CNS and systemic involvement. (C) 2017 S. Karger AG, Basel
  • Shin-ichiro Fujiwara, Kazuo Muroi, Chihiro Yamamoto, Kaoru Hatano, Kiyoshi Okazuka, Kazuya Sato, Iekuni Oh, Ken Ohmine, Takahiro Suzuki, Keiya Ozawa
    HEMATOLOGY 22(6) 347-353 2017年  査読有り
    Objectives: CD25 has been reported to be highly expressed in leukemia stem cells and correlated with adverse outcomes in young patients with acute myeloid leukemia (AML). However, the significance of CD25 expression in elderly patients with AML has not yet been investigated. Methods: We retrospectively analyzed 154 newly diagnosed AML patients aged 60 years or over by flow cytometry. Results: CD25-positive AML was characterized by high white blood cell counts, secondary AML, rare favorable karyotypes, and positivity for CD34 and CD7 antigens, compared with CD25-negative AML. CD25 positivity was significantly correlated with an inferior complete remission (CR), event-free survival (EFS), and overall survival. Multivariate analysis showed CD25 positivity to be a significant prognostic predictor of CR and EFS. A regimen of low-dose cytarabine and aclarubicin combined with granulocyte-colony-stimulating factor (CAG) led to higher CR rates in the CD25-positive AML patients than intensive chemotherapies. CD25 expression was increased at relapse and in the development of leukemic status from myelodysplastic syndrome or myeloproliferative neoplasm. Discussion: An effective treatment strategy for elderly patients with CD25-positive AML has not been established. Further studies are needed to evaluate the effect of a CAG regimen and allogenic stem cell transplantation in patients. Conclusion: CD25 is an independent prognostic factor in elderly AML patients. Alternative therapies for CD25-positive elderly AML patients are needed.
  • Chihiro Yamamoto, Shoko Ito, Kiyomi Mashima, Kento Umino, Daisuke Minakata, Ryoko Yamasaki, Yasufumi Kawasaki, Miyuki Sugimoto, Hirofumi Nakano, Masahiro Ashizawa, Kiyoshi Okazuka, Kaoru Hatano, Kazuya Sato, Lekuni Oh, Shin-Ichiro Fujiwara, Ken Ohmine, Takahiro Suzuki, Kazuo Muroi, Yoshinobu Kanda
    LEUKEMIA & LYMPHOMA 57(11) 2541-2547 2016年11月  査読有り
    The combination of mitoxantrone (MIT), etoposide (ETP), and cytarabine (Ara-C) (MEC) is a frequently used salvage therapy for acute leukemia, but has been associated with severe myelosuppression. Therefore, we investigated the miniMEC regimen with reduced doses of AraC and MIT. Thirteen ALL and 44 AML patients, all relapsed or refractory, received miniMEC, which consisted of MIT at 8 mg/m(2) for 3 d, ETP at 100 mg/m(2) for 5 d, and Ara-C at 100 mg/m(2) infused over 24 h for 7 d. CR + CRi was achieved in eight ALL patients (61.5%) and 16 AML patients (36.4%). Median duration of neutropenia was 30 d (range, 1-50). Thirty-one patients (54.4%) subsequently received allogeneic stem cell transplantation (SCT), and overall survival was significantly improved in this group (median OS 161 versus 481 d, p=0.006). We concluded that miniMEC is a safe and effective bridging therapy to SCT.
  • Miyuki Sugimoto, Shoko Ito, Kiyomi Mashima, Kento Umino, Daisuke Minakata, Hirofumi Nakano, Ryoko Yamasaki, Yasufumi Kawasaki, Masahiro Ashizawa, Chihiro Yamamoto, Shin-ichiro Fujiwara, Kiyoshi Okazuka, Kaoru Hatano, Kazuya Sato, Iekuni Oh, Ken Ohmine, Takahiro Suzuki, Kazuo Muroi, Shinichi Kako, Yoshinobu Kanda
    ANNALS OF HEMATOLOGY 95(9) 1513-1519 2016年9月  査読有り
    The BEAM regimen consisting of carmustine (BCNU), etoposide, cytarabine, and melphalan (MEL) is widely used before autologous hematopoietic stem cell transplantation (auto-HSCT) for lymphoma. However, intravenous BCNU is not available in Japan, and therefore, ranimustine (MCNU) has been used instead of BCNU (the MEAM regimen). We retrospectively analyzed the outcome of 79 adult patients who underwent auto-HSCT for lymphoma using this regimen in two centers, with 1- and 2-day dosing of MEL, respectively. Three-year overall survival (OS) and progression-free survival (PFS) probabilities were 77.3 and 56.5 % in the entire population and 71.7 and 58.0 % in patients with diffuse large B cell lymphoma. These outcomes were at least equivalent to those with the BEAM regimen. There was no regimen-related pulmonary toxicity. In a multivariate analysis, older age was the only factor that was significantly associated with for OS. In a comparison of the two MEL dosing schedules, while there was no significant differences in either OS or PFS, diarrhea was observed more frequently with 1-day dosing of MEL. In conclusion, the MEAM regimen appeared to be a promising conditioning regimen in auto-HSCT for lymphoma. A large prospective study is warranted to confirm the current findings.
  • Daisuke Minakata, Shin-ichiro Fujiwara, Shoko Ito, Kiyomi Mashima, Kento Umino, Hirofumi Nakano, Yasufumi Kawasaki, Miyuki Sugimoto, Ryoko Yamasaki, Chihiro Yamamoto, Masahiro Ashizawa, Kaoru Hatano, Kiyoshi Okazuka, Kazuya Sato, Iekuni Oh, Ken Ohmine, Takahiro Suzuki, Kazuo Muroi, Yoshinobu Kanda
    LEUKEMIA RESEARCH 42 82-87 2016年3月  査読有り
    This retrospective analysis compared the efficacy of intensive induction therapy consisting of daunorubicin and cytarabine (DNR-AraC) to that of less-intensive therapy including low-dose cytarabine, aclarubicin and granulocyte colony-stimulating factor priming (CAG). Patients aged 60 years or older who were newly diagnosed as acute myeloid leukemia (AML) were analyzed. Sixty-four and 48 patients were treated with DNR-AraC and CAG, respectively. The complete remission rates, 3-year overall survival and event-free survival in the DNR-AraC group were significantly superior to those in the CAG group (65.6% vs. 29.2%, p < 0.001, 38.4% vs. 12.3%, p = 0.0033, and 20.3% vs. 7.8%, p = 0.0030, respectively), although these differences were not statistically significant in multivariate analyses. Next, we calculated a propensity score for selecting the CAG regimen from six factors. The DNR-AraC regimen was associated with better survival than the CAG regimen in a low propensity score group, but there was no difference in survival between regimens in a high propensity score group. Intensive therapy should be performed for patients with sufficient general and comorbid conditions, but less-intensive therapy may be sufficient for patients with higher age, myelodysplasia-related changes, and lower white blood cell counts, which were relevant factors in the propensity score calculation. (C) 2015 Elsevier Ltd. All rights reserved.
  • 皆方 大佑, 室井 一男, 山本 千裕, 藤原 慎一郎, 神田 善伸
    日本輸血細胞治療学会誌 61(4) 461-462 2015年  
  • Takahiro Suzuki, Iekuni Oh, Ken Ohmine, Akiko Meguro, Masaki Mori, Shin-ichiro Fujiwara, Chihiro Yamamoto, Tadashi Nagai, Keiya Ozawa
    INTERNATIONAL JOURNAL OF HEMATOLOGY 101(1) 32-36 2015年1月  査読有り
    Erythropoiesis-stimulating agents (ESAs) are used to ameliorate anemia in lower-risk myelodysplastic syndromes (MDS). Serum erythropoietin (EPO) level < 500 IU/L is widely accepted as a major predictive factor for response to ESAs. However, few data about EPO levels in the Japanese population are available. We therefore evaluated distribution of serum EPO levels in Japanese patients with MDS. Forty-three cases were analyzed; 30 were classified as lower-risk MDS (low or intermediate-1 by the international prognostic scoring system). Twenty-two cases were transfusion dependent. The overall median hemoglobin level was 7.7 g/dL. The median value of serum EPO was 254 IU/L (range: 16.4-23,000). Serum EPO levels had a strong inverse correlation with hemoglobin levels, and a significantly larger proportion of patients showed high EPO levels (> 500 IU/L) in the transfusion-dependent group. In the higher-risk group, no significant correlation between EPO and hemoglobin was observed. Regression analyses showed that serum EPO of 500 IU/L corresponds to 8.29 g/dL of hemoglobin in lower-risk MDS. The results indicate that patients with hemoglobin levels of 8.0 g/dL or more, who are still transfusion independent, may be good candidates for ESA treatment.
  • Tomonori Tsukahara, Ken Ohmine, Chihiro Yamamoto, Ryosuke Uchibori, Hiroyuki Ido, Takeshi Teruya, Masashi Urabe, Hiroaki Mizukami, Akihiro Kume, Masataka Nakamura, Junichi Mineno, Kazutoh Takesako, Isabelle Riviere, Michel Sadelain, Renier Brentjens, Keiya Ozawa
    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 438(1) 84-89 2013年8月  査読有り
    Adoptive T-cell therapy with CD19-specific chimeric antigen receptors (CARs) is promising for treatment of advanced B-cell malignancies. Tumor targeting of CAR-modified T-cells is likely to contribute therapeutic potency; therefore we examined the relationship between the ability of CD19-specific CAR (CD19-CAR)-transduced T-cells to accumulate at CD19(+) tumor lesions, and their ability to provide antitumor effects in xenograft mouse models. Normal human peripheral blood lymphocytes, activated with immobilized RetroNectin and anti-CD3 antibodies, were transduced with retroviral vectors that encode CD19-CAR. Expanded CD19-CAR T-cells with a high transgene expression level of about 75% produced IL-2 and IFN-gamma in response to CD19, and lysed both Raji and Daudi CD19(+) human B-cell lymphoma cell lines. Furthermore, these cells efficiently accumulated at Raji tumor lesions where they suppressed tumor progression and prolonged survival in tumor-bearing Rag2(-/-)gamma c(-/-) immunodeficient mice compared to control cohorts. These results show that the ability of CD19-CAR T-cells to home in on tumor lesions is pivotal for their anti-tumor effects in our xenograft models, and therefore may enhance the efficacy of adoptive T-cell therapy for refractory B-cell lymphoma. (C) 2013 Elsevier Inc. All rights reserved.
  • Muroi K, Fujiwara S, Tatara R, Sugimoto M, Yamamoto C, Uehara E, Meguro A, Hatano K, Okazuka K, Oh I, Ohmine K, Suzuki T, Mori M, Nagai T, Ozawa K
    Journal of clinical and experimental hematopathology : JCEH 53(3) 247-250 2013年  査読有り
    Bone marrow mononuclear cells from 93 patients with hematological malignancies after allogeneic hematopoietic stem cell transplantation (AHSCT) were analyzed using flow cytometry (FCM). The disease was acute myeloblastic leukemia (50 patients), acute lymphoblastic leukemia, and others. Conditioning was myeloablative (80 patients) or reduced intensity. The stem cell source was bone marrow (75 patients), peripheral blood stem cells, or cord blood. After AHSCT, granulocyte colony-stimulating factor was given to all patients. All patients showed engraftment of the donor cells. FCM was conducted on a median of 22 days after AHSCT. The gate was set around a granulocytic region consisting of immature granulocytes. The positivity rates of CD13, CD14, CD15, CD33, CD34, CD56, and HLA-DR in the cells were 59.9 ± 27.4%, 5.8 ± 8.8%, 98.3 ± 1.9%, 92.3 ± 12.4%, 2.6 ± 5.8%, 24.3 ± 16.7%, and 9.1 ± 6.6%, respectively. The greatest value of CD56 positivity was 73.1%. On the basis of CD56 expression, cases of more than 24% CD56 positivity were assigned to the CD56-high group (39 patients), while the rest were assigned to the CD56-low/negative group. There were no significant differences between the two groups in terms of disease status, sex, donor, hematopoietic stem cells, days of FCM analysis, or peripheral blood cell counts around the days of performing FCM. These results indicate that CD56 can be expressed in normal immature granulocytes at a variety of expression levels in regenerative bone marrow. Attention should be paid when evaluating aberrant antigen expression of CD56 in granulocytes. [J Clin Exp Hematop 53(3) : 247-250, 2013]
  • 杉本 美幸, 藤原 慎一郎, 細沼 里江, 西川 彰則, 山本 千裕, 上澤 光世, 小林 洋行, 松 春子, 岡部 寛, 上原 英輔, 多々良 礼音, 翁 家国, 松山 智洋, 大嶺 謙, 鈴木 隆浩, 尾崎 勝俊, 森 政樹, 永井 正, 小澤 敬也, 室井 一男
    日本輸血細胞治療学会誌 58(2) 267-267 2012年4月  査読有り
  • Akiko Meguro, Katsutoshi Ozaki, Kazuya Sato, Iekuni Oh, Shinichiro Fujiwara, Rie Hosonuma, Miyuki Sasazaki, Yuji Kikuchi, Yuji Hirata, Chihiro Yamamoto, Mitsuyo Uesawa, Hiroyuki Kobayashi, Haruko Matsu, Hiroshi Okabe, Eisuke Uehara, Akinori Nishikawa, Raine Tatara, Kaoru Hatano, Chizuru Yamamoto, Tomohiro Matsuyama, Masaki Toshima, Masuzu Ueda, Ken Ohmine, Takahiro Suzuki, Masaki Mori, Tadashi Nagai, Kazuo Muroi, Keiya Ozawa
    LEUKEMIA & LYMPHOMA 53(1) 43-49 2012年1月  査読有り
    In the rituximab era, several large studies have suggested that full-dose rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) might be the best treatment for patients with diffuse large B-cell lymphoma (DLBCL) aged 60 years and older. However, it remains unclear whether this is also the case for those aged 70 years and older. Previously untreated patients with DLBCL aged 70 years and older (elderly) were treated with R-70%CHOP, and patients younger than 70 years (younger) were treated with full-dose R-CHOP every 3 weeks, for a total of 6-8 cycles. Complete remission (CR) rates in elderly versus younger patients were 75 vs. 78% (p = 0.7), respectively. The 3-year overall survival, event-free survival and progression-free survival of elderly versus younger patients were 58 vs. 78% (p < 0.05), 45 vs. 70% (p < 0.05) and 64 vs. 72% (p = 0.43), respectively. Severe adverse events were more frequent in the elderly, even with the dose reduction in that age group. Three-year PFS with R-70% CHOP for patients aged 70 years and older was not significantly worse than that with full-dose R-CHOP for younger patients, suggesting that R-70% CHOP might be a reasonable choice for patients with DLBCL aged 70 years and older, especially for those with comorbidities.
  • 藤原 慎一郎, 永井 正, 菊池 悟, 上澤 光世, 山本 千裕, 大嶺 謙, 上原 英輔, 菊池 次郎, 古川 雄祐, 小澤 敬也
    日本癌学会総会記事 69回 161-162 2010年8月  
  • Tadashi Nagai, Ken Ohmine, Shin-ichiro Fujiwara, Mitsuyo Uesawa, Chihiro Sakurai, Keiya Ozawa
    LEUKEMIA RESEARCH 34(8) 1057-1063 2010年8月  査読有り
    Small molecules are attractive agents for the treatment of leukemia. We found that a combination of a farnesyltransferase inhibitor, tipifarnib, and an mTOR inhibitor, rapamycin, synergistically inhibited the growth of myeloid leukemia cell lines and primary leukemia cells by inducing apoptosis and cell-cycle blockage. The combined agents reduced the level of phospho-ERK1/2, suggesting that they altered the network of signaling pathways. They also showed synergistic effects in tipifarnib-resistant K562/RR cells. The results support the utility of this combination as a potential therapy for leukemia. The combination might also be effective in overcoming resistance to tipifarnib. (C) 2010 Elsevier Ltd. All rights reserved.
  • Chihiro Sakurai, Kazuteru Ohashi, Kyogo Sakaguchi, Tsunekazu Hishima, Noriko Kamata, Hideki Akiyama, Hisashi Sakamaki
    INTERNATIONAL JOURNAL OF HEMATOLOGY 90(4) 532-536 2009年11月  査読有り
    We report the first case of Mikulicz's disease (MD) occurring 2 years after autologous peripheral blood stem cell transplantation (PBSCT) for multiple myeloma (MM). A 70-year-old man developed bilateral enlargement of parotid and submandibular glands. The patient had previously received 2 courses of autologous PBSCT for IgG-kappa type MM, and had been stable for 2 years. This salivary gland enlargement was initially felt to represent a recurrence of MM, since along with gland swelling, IgG was also elevated. However, repeated biopsy of the left submandibular gland revealed chronic sclerosing sialadenitis rather than plasmacytoma. Results of salivary gland scintigraphy, serological testing, and absence of sicca symptoms also supported the diagnosis of MD. Concurrently, the patient developed severe thrombocytopenia (0.8 x 10(4)/mu l). Bone marrow biopsy showed abundant megakaryocytes, suggesting enhanced platelet destruction. After high-dose steroid and immunoglobulin therapy, the platelet count gradually returned to normal with complete resolution of the salivary gland enlargement. No apparent signs of MM recurrence were documented during these clinical events.
  • Mori M, Muroi K, Matsuyama T, Oka S, Ono Y, Yamamoto C, Uesawa M, Okabe H, Matsu H, Tatara R, Kikuchi Y, Fujiwara S, Kikuchi S, Sato K, Ueda M, Toshima M, Ozaki K, Takatoku M, Nagai T, Ozawa K
    [Rinsho ketsueki] The Japanese journal of clinical hematology 48(8) 624-631 2007年8月  査読有り

MISC

 14

共同研究・競争的資金等の研究課題

 1