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Featured researches published by Tsukasa Ishiwata.


International Journal of Oncology | 2016

Drug resistance originating from a TGF-β/FGF-2-driven epithelial-to-mesenchymal transition and its reversion in human lung adenocarcinoma cell lines harboring an EGFR mutation

Ryota Kurimoto; Shunichiro Iwasawa; Takahiro Ebata; Tsukasa Ishiwata; Ikuo Sekine; Yuji Tada; Koichiro Tatsumi; Shuhei Koide; Atsushi Iwama; Yuichi Takiguchi

Epithelial-to-mesenchymal transition (EMT) is a malignant cancer phenotype characterized by augmented invasion and metastasis, chemoresistance, and escape from host-immunity. This study sought to identify efficient methods for inducing EMT reversion, to evaluate alterations in chemosensitivity and immune-protectiveness, and to elucidate the underlying mechanisms. In this study, the human lung adenocarcinoma cell lines PC-9 and HCC-827, harboring an EGFR mutation, were treated with TGF-β and FGF-2 to induce EMT. The phenotypic alterations were evaluated by RT-PCR, fluorescent immunohistochemistry, cell-mobility, and flow cytometry. Chemosensitivity to gefitinib and cisplatin was evaluated using an MTT assay and apoptosis. Immune-protectiveness was evaluated by PD-L1 expression. A combination of TGF-β and FGF-2 efficiently induced EMT in both cell lines: through Smad3 pathway in PC-9, and through Smad3, MEK/Erk, and mTOR pathways in HCC-827. The mTOR inhibitor PP242, metformin, and DMSO reverted EMT to different extent and through different pathways, depending on the cell lines. EMT induction reduced the sensitivity to gefitinib in both cell lines and to cisplatin in HCC-827, and it increased PD-L1 expression in both cell lines. EMT reversion using each of the 3 agents partly restored chemosensitivity and suppressed PD-L1 expression. Thus, chemoresistance and increased PD-L1 expression caused by EMT can be successfully reverted by EMT-reverting agents.


Drug Design Development and Therapy | 2015

Efficacy of thrombomodulin for acute exacerbation of idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia: a nonrandomized prospective study

Mitsuhiro Abe; Kenji Tsushima; Takuma Matsumura; Tsukasa Ishiwata; Yasunori Ichimura; Jun Ikari; Jiro Terada; Yuji Tada; Seiichirou Sakao; Nobuhiro Tanabe; Koichiro Tatsumi

Purpose Acute exacerbation (AE) is an important outcome of idiopathic pulmonary fibrosis (IPF) and nonspecific interstitial pneumonia (NSIP). Recombinant human soluble thrombomodulin (rhTM) is a new drug for the treatment of disseminated intravascular coagulation in Japan. The objective of this study was to evaluate the efficacy of rhTM for AE of IPF/NSIP. Methods Twenty-two patients with AE-idiopathic interstitial pneumonia (16 patients with IPF and six patients with NSIP) were enrolled in our study. Among them, eleven patients were treated with rhTM (rhTM group), and eleven patients were treated without rhTM (non-rhTM group). Patients admitted to our hospital prior to December 2013 were treated with rhTM, while those admitted after January 2014 were treated without rhTM. The primary endpoint was mortality at 90 days after AE treatment. The secondary endpoint was the safety of rhTM for AE-IPF/AE-NSIP. In addition, we examined prognostic factors of AE-IPF/AE-NSIP. Results The mortality rate was significantly lower in the rhTM group than in the non-rhTM group (mortality rate at 90 days: 36% vs 90%, P=0.023; median survival time: not reached vs 15.0 days, P=0.019). A univariate analysis revealed the respiratory rate (hazard ratio [HR] 1.09, 95% confidence interval [CI] 1.00–1.18, P=0.039) and rhTM administration (HR 0.21, 95% CI 0.06–0.77, P=0.013) as predictors of mortality at 90 days, and a multivariate analysis identified rhTM administration (HR 0.025, 95% CI 0.0006–0.94, P=0.046) as an independent predictor of mortality at 90 days. No serious adverse events were observed. Conclusion The administration of rhTM is associated with reductions in mortality in patients with AE-IPF/NSIP, without causing adverse events.


Oncology Letters | 2017

Pirfenidone may revert the epithelial-to-mesenchymal transition in human lung adenocarcinoma

Ryota Kurimoto; Takahiro Ebata; Shunichiro Iwasawa; Tsukasa Ishiwata; Yuji Tada; Koichiro Tatsumi; Yuichi Takiguchi

The epithelial-to-mesenchymal transition (EMT) in cancer is associated with invasion, metastasis and chemoresistance. Recent studies have revealed the increased expression of programmed death-ligand 1 (PD-L1) in cells undergoing EMT. The underlying mechanism of EMT involves transforming growth factor-β (TGF-β) and fibroblast growth factor-2 (FGF-2). Pirfenidone and the known EMT-suppressor nintedanib suppress pulmonary fibrosis partially through suppression of TGF-β. The present study aimed to determine whether pirfenidone has the potential to induce EMT-reversion, using nintedanib as a reference. The human lung adenocarcinoma cell lines A-549, HCC-827, and PC-9 were treated with TGF-β and FGF-2 to induce EMT. The EMT-induced cells were further treated with pirfenidone or nintedanib. Phenotypic alterations associated with EMT were assessed by examining the following: i) The expression levels of E-cadherin, vimentin, fibronectin and slug, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and fluorescent immunohistochemistry; ii) cell motility via wound-healing assays; and iii) the expression of PD-L1 using RT-qPCR. The combination of TGF-β and FGF-2 successfully induced EMT in all three cell lines, characterized by a significant reduction in E-cadherin expression in the A-549 and HCC-827 cells, increased expression levels of vimentin, fibronectin, slug and PD-L1, and increased cell motility in all three cell lines. Pirfenidone and nintedanib reverted all of these phenotypes, with the exception of unaltered E-cadherin expression in all three cell lines, and inconsistent expression of vimentin in the HCC-827 and PC-9 cells. Thus, pirfenidone and nintedanib have the ability to induce EMT-reversion in human lung adenocarcinoma.


Oncology | 2017

Amrubicin Monotherapy for Patients with Platinum-Pretreated Non-Gastrointestinal Non-Pancreatic Extrapulmonary Neuroendocrine Carcinoma

Takahiro Ebata; Tatsunori Shimoi; Tsukasa Ishiwata; Shunichiro Iwasawa; Seiko Bun; Mayu Yunokawa; Kan Yonemori; Yuichi Takiguchi; Kenji Tamura

Objective: The aim of this study was to investigate the clinical usefulness of amrubicin therapy for patients with non-gastrointestinal (GI) non-pancreatic extrapulmonary neuroendocrine carcinoma (EP-NEC). Methods: The medical records of patients from the 2 participating institutions were retrospectively reviewed. The eligibility criteria were: patients with non-GI non-pancreatic EP-NEC who received amrubicin monotherapy after platinum-based chemotherapy. Patients in whom the platinum-free interval (interval between the last day of platinum administration and the first subsequent documentation of disease progression) was 90 days or longer were classified into the platinum-sensitive group. Results: The study was conducted in a total of 13 patients identified as eligible. The response rate was 45.4% (5/11). The median progression-free survival and overall survival were 6.0 and 10.6 months, respectively. A platinum-free interval of ≥90 days was identified as a significant predictor of a longer progression-free survival time. Grade 3 or 4 neutropenia was observed in 61.5% (8/13) of the patients. One patient died of treatment-related febrile neutropenia. Conclusions: Amrubicin monotherapy as second-line chemotherapy after failure of first-line platinum-based chemotherapy showed good efficacy in patients with non-GI non-pancreatic EP-NEC. Neutropenia was encountered as the most serious adverse event.


Respiratory investigation | 2018

Safety of diagnostic flexible bronchoscopy in patients with echocardiographic evidence of pulmonary hypertension

Tsukasa Ishiwata; Mitsuhiro Abe; Hajime Kasai; Jun Ikari; Naoko Kawata; Jiro Terada; Seiichiro Sakao; Yuji Tada; Nobuhiro Tanabe; Koichiro Tatsumi

BACKGROUND The presence of pulmonary hypertension (PH) and treatment with anticoagulant agents could potentially increase the risk for bleeding/hemodynamic complications associated with bronchoscopic procedures. The aim of this study was to assess the safety of diagnostic flexible bronchoscopy (FB) in patients with PH. METHODS A retrospective review of clinical records of patients with echocardiographic evidence of PH (right ventricular systolic pressure [RVSP] > 40 mm Hg) who underwent diagnostic FB between 2004 and 2016 at a single facility in Japan was conducted. Patients with no clinical evidence suggestive of PH who underwent FB during the same period were enrolled as a pairwise-matched control group; factors used in matching included age, sex, and performed procedures. RESULTS Overall, there were 45 patients in the PH group and 90 patients in the control group. Six (13%) patients in the PH group had severe PH (RVSP > 61 mm Hg). Forceps biopsies and transbronchial needle aspirations were performed in 62% and 13% of patients, respectively, in the PH group, and 58% and 13% of patients, respectively, in the control group. The total incidence of bleeding during FB was not significantly different between the two groups (18% versus 16%; p = 0.742). Vital signs recorded 2 h after FB were also not significantly different between the two groups. There were no episodes of cardiac arrhythmias or deaths associated with the FB procedures. CONCLUSIONS The data suggest that diagnostic FB procedures can be performed safely in patients with echocardiographic evidence of PH.


Respiration | 2018

Efficacy of End-Tidal Capnography Monitoring during Flexible Bronchoscopy in Nonintubated Patients under Sedation: A Randomized Controlled Study

Tsukasa Ishiwata; Kenji Tsushima; Jiro Terada; Mai Fujie; Mitsuhiro Abe; Jun Ikari; Naoko Kawata; Yuji Tada; Koichiro Tatsumi

Background: Although appropriate sedation is recommended during flexible bronchoscopy (FB), patients are at risk for hypoventilation due to inadvertent oversedation. End-tidal capnography is expected as an additional useful monitor for these patients during FB. Objectives: The aim of this study was to evaluate the benefit of additional end-tidal capnography monitoring in reducing the incidence of hypoxemia during FB in patients under sedation. Methods: Patients undergoing FB under moderate sedation without tracheal intubation were randomly assigned to receive standard monitoring including pulse oximetry or additional capnography monitoring. Bronchoscopy examiners for the only capnography group were informed of apnea events by alarms and display of the capnography monitor. Results: A total of 185 patients were enrolled. Patient characteristics were well balanced between the two groups. Hypoxemia (at least one episode of pulse oximeter oxygen saturation [SpO2] < 90%) was observed in 27 out of 94 patients in the capnography group (29%) and in 42 out of 91 patients in the control group (46%; p = 0.014), resulting in an absolute risk difference of −17.4% (95% confidence interval, −31.1 to −3.7). In the capnography group, hypoxemia duration was shorter (20.4 vs. 41.7 s, p = 0.029), severe hypoxemic events (SpO2 < 85%) were observed less frequently (16 [17%] vs. 29 [32%], p = 0.019), and the mean lowest SpO2 value was higher (90.5 vs. 87.6%, p = 0.002). Conclusion: End-tidal capnography monitoring can reduce the incidence and duration of hypoxemia during FB in nonintubated patients under sedation.


Internal Medicine | 2017

Nivolumab-induced Acute Fibrinous and Organizing Pneumonia (AFOP)

Tsukasa Ishiwata; Takahiro Ebata; Shunichiro Iwasawa; Jun Matsushima; Satoshi Ota; Yukio Nakatani; Kenji Tsushima; Yuji Tada; Koichiro Tatsumi; Yuichi Takiguchi

Although nivolumab is known to cause immune-related interstitial lung diseases (ILD), the detailed characteristics of ILD are still not fully understood. A 68-year-old man was treated with nivolumab because of unresectable sinonasal melanoma, he achieved a complete response soon after the initiation of the therapy and a complete response was thereafter maintained for 30 weeks until the patient experienced dyspnea of subacute onset. CT images revealed patchy infiltrates and ground-glass opacifications. The bronchoalveolar lavage fluid (BALF) contained elevated percentages of lymphocytes (53%) and neutrophils (30%). A transbronchial lung biopsy revealed intraalveolar fibrin balls without hyaline membranes, which was considered to be consistent with the pattern of acute fibrinous and organizing pneumonia (AFOP). This is the first report of AFOP induced by nivolumab.


Cancer Research | 2016

Abstract 239: Alteration of drug sensitivity according to the induction and reversion of epithelial-to-mesenchymal transition (EMT) in human lung adenocarcinoma cell lines harboring an EGFR mutation

Ryota Kurimoto; Shunichiro Iwasawa; Takahiro Ebata; Tsukasa Ishiwata; Ikuo Sekine; Yuji Tada; Koichiro Tatsumi; Shuhei Koide; Atsushi Iwama; Yuichi Takiguchi

Proceedings: AACR 107th Annual Meeting 2016; April 16-20, 2016; New Orleans, LA Introduction: EMT phenotype is known to relate to drug resistance and immune tolerance of cancer. However, mechanism underling these phenomena, including the mechanism of the induction and reversion of EMT, are not fully understood. Methods: EGFR mutated human lung adenocarcinoma cell lines, HCC-827 and PC-9, were treated with TGF-s and/or FGF-2 to induce EMT. EMT was reversed by treating the induced EMT cells with either of PP242 (mTOR inhibitor), metformin and DMSO. The phenotypic alterations according to the induction and reversion of EMT were accessed by a wound healing assay for mobility, flow cytometry for cell cycle, MTT and apoptosis assays for drug sensitivity to cisplatin and gefitinib, and RT-PCR and fluorescence IHC for PD-L1 expression. Results: The treatment with combination of TGF-s/FGF-2 showed an efficient increase in expressions of mesenchymal markers and slug in both cell lines, and a decrease in E-cadherin expression in HCC827. In immunoblotting analyses, the Smad3 pathway in PC-9, and the Smad3, MEK/Erk and mTOR pathways in HCC-827 were involved in the induction of the EMT. The induced EMT was accompanied by enhanced cell motility and accumulation in the G0/G1 phases in both cell lines. The induced EMT also made the cells less sensitive to gefitinib in both cell lines, and to cisplatin in HCC-827. Increased PD-L1 expression was observed in both cell lines. Treatment of the induced EMT cells with PP242, metformin and DMSO reverted the altered expressions of epithelial and mesenchymal markers, cell motility and cell cycle. These agents reverted the EMT to different extents and through different pathways, depending on the cell lines. Reversion of the EMT using each of the 3 agents partly restored drug sensitivity, and suppressed PD-L1 expression. Conclusion: Inducing EMT by treatment with TGF-s/FGF-2 is an effective way to acquire drug resistance and up-regulation of PD-L1. Reversion of the EMT, therefore, has a potential to overcome drug resistance and immune tolerance of cancer. Citation Format: Ryota Kurimoto, Shunichiro Iwasawa, Takahiro Ebata, Tsukasa Ishiwata, Ikuo Sekine, Yuji Tada, Koichiro Tatsumi, Shuhei Koide, Atsushi Iwama, Yuichi Takiguchi. Alteration of drug sensitivity according to the induction and reversion of epithelial-to-mesenchymal transition (EMT) in human lung adenocarcinoma cell lines harboring an EGFR mutation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 239.


American Journal of Medical Genetics Part A | 2016

Moyamoya disease and artery tortuosity as rare phenotypes in a patient with an elastin mutation

Tsukasa Ishiwata; Nobuhiro Tanabe; Ayako Shigeta; Hajime Yokota; Kenji Tsushima; Jiro Terada; Seiichiro Sakao; Hiroko Morisaki; Takayuki Morisaki; Koichiro Tatsumi

Sporadic and familial elastin mutations can occur in large vessel stenosis such as supravalvular aortic stenosis and narrowing of the descending aorta. However, there are very few reports regarding the arteriopathy of cerebral, pulmonary or abdominal arteries in elastin mutations. We herein report the case of a Japanese female patient presenting with multiple arteriopathy including moyamoya disease, a tortuosity of abdominal arteries and pulmonary hypertension due to peripheral pulmonary artery stenosis. This case suggests the possible progression of cerebral arteriopathy including moyamoya disease in patients with elastin mutations.


Internal Medicine | 2014

Pulmonary Arterial Hypertension as the First Manifestation in a Patient with Hereditary Hemorrhagic Telangiectasia

Tsukasa Ishiwata; Jiro Terada; Nobuhiro Tanabe; Mitsuhiro Abe; Toshihiko Sugiura; Kenji Tsushima; Yuji Tada; Seiichiro Sakao; Yasunori Kasahara; Norifumi Nakanishi; Hiroko Morisaki; Koichiro Tatsumi

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