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Dive into the research topics where Masahiro Hirakawa is active.

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Featured researches published by Masahiro Hirakawa.


The New England Journal of Medicine | 2016

Ipilimumab for Patients with Relapse after Allogeneic Transplantation

Matthew S. Davids; Haesook T. Kim; Pavan Bachireddy; Caitlin Costello; Rebecca Liguori; Alexandra Savell; Alexander Lukez; David Avigan; Yi-Bin Chen; Peter A. McSweeney; Nicole R. LeBoeuf; Michael S. Rooney; Michaela Bowden; Chensheng W. Zhou; Scott R. Granter; Jason L. Hornick; Scott J. Rodig; Masahiro Hirakawa; Mariano Severgnini; F. Stephen Hodi; Catherine J. Wu; Vincent T. Ho; Corey Cutler; John Koreth; Edwin P. Alyea; Joseph H. Antin; Philippe Armand; Howard Streicher; Edward D. Ball; Jerome Ritz

BACKGROUND Loss of donor-mediated immune antitumor activity after allogeneic hematopoietic stem-cell transplantation (HSCT) permits relapse of hematologic cancers. We hypothesized that immune checkpoint blockade established by targeting cytotoxic T-lymphocyte-associated protein 4 with ipilimumab could restore antitumor reactivity through a graft-versus-tumor effect. METHODS We conducted a phase 1/1b multicenter, investigator-initiated study to determine the safety and efficacy of ipilimumab in patients with relapsed hematologic cancer after allogeneic HSCT. Patients received induction therapy with ipilimumab at a dose of 3 or 10 mg per kilogram of body weight every 3 weeks for a total of 4 doses, with additional doses every 12 weeks for up to 60 weeks in patients who had a clinical benefit. RESULTS A total of 28 patients were enrolled. Immune-related adverse events, including one death, were observed in 6 patients (21%), and graft-versus-host disease (GVHD) that precluded further administration of ipilimumab was observed in 4 patients (14%). No responses that met formal response criteria occurred in patients who received a dose of 3 mg per kilogram. Among 22 patients who received a dose of 10 mg per kilogram, 5 (23%) had a complete response, 2 (9%) had a partial response, and 6 (27%) had decreased tumor burden. Complete responses occurred in 4 patients with extramedullary acute myeloid leukemia and 1 patient with the myelodysplastic syndrome developing into acute myeloid leukemia. Four patients had a durable response for more than 1 year. Responses were associated with in situ infiltration of cytotoxic CD8+ T cells, decreased activation of regulatory T cells, and expansion of subpopulations of effector T cells in the blood. CONCLUSIONS Our early-phase data showed that administration of ipilimumab was feasible in patients with recurrent hematologic cancers after allogeneic HSCT, although immune-mediated toxic effects and GVHD occurred. Durable responses were observed in association with several histologic subtypes of these cancers, including extramedullary acute myeloid leukemia. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT01822509.).


PLOS ONE | 2012

Targeting anticancer drug delivery to pancreatic cancer cells using a fucose-bound nanoparticle approach.

Makoto Yoshida; Rishu Takimoto; Kazuyuki Murase; Yasushi Sato; Masahiro Hirakawa; Fumito Tamura; Tsutomu Sato; Satoshi Iyama; Takahiro Osuga; Koji Miyanishi; Kohichi Takada; Tsuyoshi Hayashi; Masayoshi Kobune; Junji Kato

Owing to its aggressiveness and the lack of effective therapies, pancreatic ductal adenocarcinoma has a dismal prognosis. New strategies to improve treatment and survival are therefore urgently required. Numerous fucosylated antigens in sera serve as tumor markers for cancer detection and evaluation of treatment efficacy. Increased expression of fucosyltransferases has also been reported for pancreatic cancer. These enzymes accelerate malignant transformation through fucosylation of sialylated precursors, suggesting a crucial requirement for fucose by pancreatic cancer cells. With this in mind, we developed fucose-bound nanoparticles as vehicles for delivery of anticancer drugs specifically to cancer cells. L-fucose-bound liposomes containing Cy5.5 or Cisplatin were effectively delivered into CA19-9 expressing pancreatic cancer cells. Excess L-fucose decreased the efficiency of Cy5.5 introduction by L-fucose-bound liposomes, suggesting L-fucose-receptor-mediated delivery. Intravenously injected L-fucose-bound liposomes carrying Cisplatin were successfully delivered to pancreatic cancer cells, mediating efficient tumor growth inhibition as well as prolonging survival in mouse xenograft models. This modality represents a new strategy for pancreatic cancer cell-targeting therapy.


JCI insight | 2016

Low-dose IL-2 selectively activates subsets of CD4+ Tregs and NK cells

Masahiro Hirakawa; Tiago R. Matos; Hongye Liu; John Koreth; Haesook T. Kim; Nicole E. Paul; Kazuyuki Murase; Jennifer Whangbo; Ana Cristina Alho; Sarah Nikiforow; Corey Cutler; Vincent T. Ho; Philippe Armand; Edwin P. Alyea; Joseph H. Antin; Bruce R. Blazar; João F. Lacerda; Robert J. Soiffer; Jerome Ritz

CD4+ regulatory T cells (CD4Tregs) play a critical role in the maintenance of immune tolerance and prevention of chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation. IL-2 supports the proliferation and survival of CD4Tregs and previous studies have demonstrated that IL-2 induces selective expansion of CD4Tregs and improves clinical manifestations of chronic GVHD. However, mechanisms for selective activation of CD4Tregs and the effects of low-dose IL-2 on other immune cells are not well understood. Using mass cytometry, we demonstrate that low concentrations of IL-2 selectively induce STAT5 phosphorylation in Helios+ CD4Tregs and CD56brightCD16- NK cells in vitro. Preferential activation and expansion of Helios+ CD4Tregs and CD56brightCD16- NK cells was also demonstrated in patients with chronic GVHD receiving low-dose IL-2. With prolonged IL-2 treatment for 48 weeks, phenotypic changes were also observed in Helios- CD4Tregs. The effects of low-dose IL-2 therapy on conventional CD4+ T cells and CD8+ T cells were limited to increased expression of PD-1 on effector memory T cells. These studies reveal the selective effects of low-dose IL-2 therapy on Helios+ CD4Tregs and CD56bright NK cells that constitutively express high-affinity IL-2 receptors as well as the indirect effects of prolonged exposure to low concentrations of IL-2 in vivo.


British Journal of Cancer | 2014

Fucosylated TGF-β receptors transduces a signal for epithelial-mesenchymal transition in colorectal cancer cells.

Masahiro Hirakawa; Rishu Takimoto; Fumito Tamura; Yoshida M; Michihiro Ono; Kazuyuki Murase; Yasushi Sato; Takahiro Osuga; Tsutomu Sato; Satoshi Iyama; Koji Miyanishi; Kohichi Takada; Tsuyoshi Hayashi; Masayoshi Kobune; Junji Kato

Background:Transforming growth factor-β (TGF-β) is a major inducer of epithelial–mesenchymal transition (EMT) in different cell types. TGF-β-mediated EMT is thought to contribute to tumour cell spread and metastasis. Sialyl Lewis antigens synthesised by fucosyltransferase (FUT) 3 and FUT6 are highly expressed in patients with metastatic colorectal cancer (CRC) and are utilised as tumour markers for cancer detection and evaluation of treatment efficacy. However, the role of FUT3 and FUT6 in augmenting the malignant potential of CRC induced by TGF-β is unclear.Methods:Colorectal cancer cell lines were transfected with siRNAs for FUT3/6 and were examined by cell proliferation, invasion and migration assays. The expression and phosphorylation status of TGF-β downstream molecules were analysed by western blot. Fucosylation of TGF-β receptor (TβR) was examined by lectin blot analysis.Results:Inhibition of FUT3/6 expression by siRNAs suppressed the fucosylation of type I TβR and phosphorylation of the downstream molecules, thereby inhibiting the invasion and migration of CRC cells by EMT.Conclusion:Fucosyltransferase 3/6 has an essential role in cancer cell adhesion to endothelial cells by upregulation of sialyl Lewis antigens and also by enhancement of cancer cell migration through TGF-β-mediated EMT.


Gastrointestinal Endoscopy | 2011

Argon plasma coagulation treatment of hemorrhagic radiation proctopathy: the optimal settings for application and long-term outcome

Yasushi Sato; Tetsuji Takayama; Tamotsu Sagawa; Masahiro Hirakawa; Hiroyuki Ohnuma; Koji Miyanishi; Tsutomu Sato; Rishu Takimoto; Masayoshi Kobune; Koichi Okamoto; Hisashi Takeuchi; Junji Kato

BACKGROUND No standard treatment exists for hemorrhagic radiation proctopathy (HRP). Recently it was reported that argon plasma coagulation (APC) is effective for HRP. However, previous studies documented complications such as ulcers, strictures, and perforations in as many as 20% of APC-treated patients. OBJECTIVE The aim of this study was to determine the optimal parameters for APC by using swine rectum and to assess the safety and effectiveness of APC in HRP patients. DESIGN Prospective case series. SETTING University teaching hospital. PATIENTS Sixty-five patients with HRP were prospectively enrolled between 2000 and 2010. INTERVENTIONS APC for HRP. MAIN OUTCOME MEASUREMENTS Optimal APC parameters, number of treatments, success rate, complications, clinical remissions. RESULTS APC in swine rectal wall ex vivo was optimal with a 40-W current, 1.2-L/min gas flow rate, and 2-second application, which was sufficient to treat the submucosal telangiectasia but did not adversely affect the muscle layer. Sixty-five patients (46 men, 19 women; median age 72 years) with HRP occurring at a mean of 20 months after radiotherapy were studied. Proctopathy was classified as grade A (mild) in 7 patients (10.8%), grade B (moderate) in 41 (63.1%), and grade C (severe) in 17 (26.2%). The treatment success rate was 98.5% after a median of 2 (range 1-5) APC sessions. The median clinical score for rectal bleeding was significantly decreased after APC (P < .0001), and the hemoglobin level was significantly increased (P < .0001). APC was well tolerated, and no significant side effects or complications occurred. During a mean follow-up of 34.6 months (range 3.6 -121.1 months), 4 patients (6.3%) had minor recurrent rectal bleeding and 60 (93.8%) remained in remission. LIMITATIONS Nonrandomized study. CONCLUSIONS HRP treatment with optimal APC settings yields a high success rate and long-lasting clinical remission with no significant complications.


Gastric Cancer | 2016

RNAi-mediated gene silencing of ST6GalNAc I suppresses the metastatic potential in gastric cancer cells

Fumito Tamura; Yasushi Sato; Masahiro Hirakawa; Makoto Yoshida; Michihiro Ono; Takahiro Osuga; Yutaka Okagawa; Naoki Uemura; Yohei Arihara; Kazuyuki Murase; Yutaka Kawano; Satoshi Iyama; Kohichi Takada; Tsuyoshi Hayashi; Tsutomu Sato; Koji Miyanishi; Masayoshi Kobune; Rishu Takimoto; Junji Kato

BackgroundST6GalNAc I is a sialyltransferase controlling the expression of sialyl-Tn antigen (STn), which is overexpressed in several epithelial cancers, including gastric cancer, and is highly correlated with cancer metastasis. However, the functional contribution of ST6GalNAc I to development or progression of gastric cancer remains unclear. In this study, we investigated the effects of suppression of ST6GalNAc I on gastric cancer in vitro and in vivo.MethodsGastric cancer cell lines were transfected with ST6GalNAc I siRNA and were examined by cell proliferation, migration, and invasion assays. We also evaluated the effect of ST6GalNAc I siRNA treatment in a peritoneal dissemination mouse model. The differences in mRNA levels of selected signaling molecules were analyzed by polymerase chain reaction (PCR) arrays associated with tumor metastasis in MKN45 cells. The signal transducer and activator of transcription 5b (STAT5b) signaling pathways that reportedly regulate the insulin-like growth factor-1 (IGF-1) were analyzed by Western blot.ResultsST6GalNAc I siRNA inhibited gastric cancer cell growth, migration, and invasion in vitro. Furthermore, intraperitoneal administration of ST6GalNAc I siRNA- liposome significantly inhibited peritoneal dissemination and prolonged the survival of xenograft model mice with peritoneal dissemination of gastric cancer. PCR array confirmed that suppression of ST6GalNAc I caused a significant reduction in expression of IGF-1 mRNA. Decreased IGF-1 expression in MKN45 cells treated with ST6GalNAc I siRNA was accompanied by reduced phosphorylation of STAT5b.ConclusionST6GalNAc I may regulate the gene expression of IGF-1 through STAT5b activation in gastric cancer cells and may be a potential target for treatment of metastasizing gastric cancer.


Endoscopy International Open | 2014

Clinical utility of capsule endoscopy with flexible spectral imaging color enhancement for diagnosis of small bowel lesions

Yasushi Sato; Tamotsu Sagawa; Masahiro Hirakawa; Hiroyuki Ohnuma; Takahiro Osuga; Yutaka Okagawa; Fumito Tamura; Hiroto Horiguchi; Kohichi Takada; Tsuyoshi Hayashi; Tsutomu Sato; Koji Miyanishi; Rishu Takimoto; Masayoshi Kobune; Junji Kato

Background and study aims: The clinical utility of computed virtual chromoendoscopy with flexible spectral imaging color enhancement (FICE) in capsule endoscopy (CE) remains controversial. To clarify the clinical utility of FICE-enhanced CE in evaluating small bowel lesions, we quantitatively assessed white light (WL), FICE, and blue mode (BM) images and examined the sensitivity of these 3 imaging modes of small-bowel lesions from patients who underwent CE. Methods: The CIELAB color difference (∆E) and visual analogue scales (VAS) were measured in 261 CE images (3 different lesion categories) using WL and FICE set 1, 2, and 3, and BM images, respectively. Three endoscopists reviewed CE videos with WL, 3 FICE mode settings, and BM, and compared the sensitivity and detectability for small intestinal diseases from 50 patients who underwent CE. Results: In the assessment of visibility in the 152 vascular lesion images, the ∆E and VAS of FICE set 1, 2, and BM images were significantly higher than that of WL images. In 88 erosion/ulceration images, the ∆E and VAS of FICE set 1 and 2 images were significantly higher than that of WL images. In 21 tumor images, there were no significant differences in ∆E among these modalities. When analyzed on a per-patient basis, FICE settings 1 and 2 had the highest sensitivity (100 %) and specificity (97.3 – 100 %) for vascular lesions. As for erosive/ulcerative lesions, FICE setting 2 had the highest sensitivity (100 %) and specificity (97.2 %). For tumors or polyps, WL had the highest sensitivity (90.9 %) and specificity (87.1 %). In per-lesion analysis, FICE settings 1 and 2 showed significantly superior detection ability over WL for vascular lesions. In the detection of erosive/ulcerative lesions, FICE setting 2 was significantly superior to WL. In tumor images, there was no significant improvement with any of the settings relative to WL images. Conclusions: FICE is most useful for improving CE image quality and detection in cases of angioectasia and erosion/ulceration of the small intestine.


Gastric Cancer | 2017

Erratum to: Conversion therapy for inoperable advanced gastric cancer patients by docetaxel, cisplatin, and S-1 (DCS) chemotherapy: a multi-institutional retrospective study

Yasushi Sato; Hiroyuki Ohnuma; Takayuki Nobuoka; Masahiro Hirakawa; Tamotsu Sagawa; Koshi Fujikawa; Yasuo Takahashi; Minami Shinya; Shinich Katsuki; Minoru Takahashi; Masahiro Maeda; Yutaka Okagawa; Uemura Naoki; Syouhei Kikuch; Koichi Okamoto; Hiroshi Miyamoto; Mitsuo Shimada; Ichiro Takemasa; Junji Kato; Tetsuji Takayama

Background Conversion therapy is an option for unresectable metastatic gastric cancer when distant metastases are controlled by chemotherapy; however, the feasibility and efficacy remain unclear. This study aimed to assess the feasibility and efficacy of conversion therapy in patients with initially unresectable gastric cancer treated with docetaxel, cisplatin, and S-1 (DCS) chemotherapy by evaluating clinical outcomes.


Digestive Endoscopy | 2010

ENDOSCOPIC FINDINGS OF ENTEROPATHY‐TYPE T‐CELL LYMPHOMA BY DOUBLE‐BALLOON ENTEROSCOPY AND CAPSULE ENDOSCOPY

Yasushi Sato; Michihiro Ono; Tamotsu Sagawa; Rishu Takimoto; Masahiro Hirakawa; Hiroyuki Ohnuma; Tsutomu Sato; Satoshi Iyama; Kazuyuki Murase; Koji Miyanishi; Masayoshi Kobune; Junji Kato

Enteropathy‐type T‐cell lymphoma (ETL) is a rare primary intestinal disorder, particularly in Japan, and there have been few reports on the endoscopic findings of the disease. Here we report detailed endoscopic findings of ETL based on double‐balloon enteroscopy and capsule endoscopy. Double‐balloon enteroscopy and capsule endoscopy may be useful tools for diagnosing and monitoring the effects of therapy in patients with ETL.


International Journal of Radiation Oncology Biology Physics | 2015

A Phase 1/2 Study of Definitive Chemoradiation Therapy Using Docetaxel, Nedaplatin, and 5-Fluorouracil (DNF-R) for Esophageal Cancer.

Hiroyuki Ohnuma; Yasushi Sato; Masahiro Hirakawa; Yutaka Okagawa; Takahiro Osuga; Tsuyoshi Hayashi; Tsutomu Sato; Koji Miyanishi; Masayoshi Kobune; Rishu Takimoto; Tamotsu Sagawa; Masakazu Hori; Masanori Someya; Kensei Nakata; Koh-ichi Sakata; Tetsuji Takayama; Junji Kato

PURPOSE Patient survival in esophageal cancer (EC) remains poor. The purpose of this study was to investigate a regimen of definitive chemoradiation therapy (CRT) that exerts good local control of EC. We performed a phase 1/2 study to assess the safety and efficacy of CRT with docetaxel, nedaplatin, and 5-fluorouracil (DNF-R). METHODS AND MATERIALS Eligible patients presented with stage IB to IV EC. Patients received 2 cycles of docetaxel (20, 30, or 40 mg/m(2)) and nedaplatin (50 mg/m(2)) on days 1 and 8 and a continuous infusion of 5-fluorouracil (400 mg/m(2)/day) on days 1 to 5 and 8 to 12, every 5 weeks, with concurrent radiation therapy (59.4 Gy/33 fractions). The recommended dose (RD) was determined using a 3 + 3 design. RESULTS In the phase 1 study, the dose-limiting toxicities were neutropenia and thrombocytopenia. The RD of docetaxel was determined to be 20 mg/m(2). In the phase 2 study, grade 3 to 4 acute toxicities included neutropenia (42.8%), febrile neutropenia (7.14%), thrombocytopenia (17.9%), and esophagitis (21.4%). Grade 3 to 4 late radiation toxicity included esophagostenosis (10.7%). The complete response rate was 82.1% (95% confidence interval: 67.9-96.3%). Both the median progression-free survival and overall survival were 41.2 months. CONCLUSIONS DNF-R showed good tolerability and strong antitumor activity, suggesting that it is a potentially effective therapeutic regimen for EC.

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Junji Kato

Sapporo Medical University

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Yasushi Sato

Sapporo Medical University

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Koji Miyanishi

Sapporo Medical University

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Masayoshi Kobune

Sapporo Medical University

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Rishu Takimoto

Sapporo Medical University

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Hiroyuki Ohnuma

Sapporo Medical University

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Tsutomu Sato

Sapporo Medical University

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Tamotsu Sagawa

Sapporo Medical University

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Kohichi Takada

Sapporo Medical University

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