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Dive into the research topics where Sadahisa Ogasawara is active.

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Featured researches published by Sadahisa Ogasawara.


Liver cancer | 2014

JSH Consensus-Based Clinical Practice Guidelines for the Management of Hepatocellular Carcinoma: 2014 Update by the Liver Cancer Study Group of Japan

Masatoshi Kudo; Osamu Matsui; Namiki Izumi; Hiroko Iijima; Masumi Kadoya; Yasuharu Imai; Takuji Okusaka; Shiro Miyayama; Kaoru Tsuchiya; Kazuomi Ueshima; Atsushi Hiraoka; Masafumi Ikeda; Sadahisa Ogasawara; Tatsuya Yamashita; Tetsuya Minami; Koichiro Yamakado

The Clinical Practice Guidelines for the Management of Hepatocellular Carcinoma proposed by the Japan Society of Hepatology was updated in June 2014 at a consensus meeting of the Liver Cancer Study Group of Japan. Three important items have been updated: the surveillance and diagnostic algorithm, the treatment algorithm, and the definition of transarterial chemoembolization (TACE) failure/refractoriness. The most important update to the diagnostic algorithm is the inclusion of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging as a first line surveillance/diagnostic tool. Another significant update concerns removal of the term “lipiodol” from the definition of TACE failure/refractoriness.


Hepatology International | 2017

Asia–Pacific clinical practice guidelines on the management of hepatocellular carcinoma: a 2017 update

Masao Omata; Ann-Lii Cheng; Norihiro Kokudo; Masatoshi Kudo; Jeong Min Lee; Jidong Jia; Ryosuke Tateishi; Kwang Hyub Han; Yoghesh K. Chawla; Shuichiro Shiina; Wasim Jafri; Diana A. Payawal; Takamasa Ohki; Sadahisa Ogasawara; Pei-Jer Chen; Cosmas Rinaldi A. Lesmana; Laurentius A. Lesmana; Rino Alvani Gani; Shuntaro Obi; A. Kadir Dokmeci; Shiv Kumar Sarin

There is great geographical variation in the distribution of hepatocellular carcinoma (HCC), with the majority of all cases worldwide found in the Asia–Pacific region, where HCC is one of the leading public health problems. Since the “Toward Revision of the Asian Pacific Association for the Study of the Liver (APASL) HCC Guidelines” meeting held at the 25th annual conference of the APASL in Tokyo, the newest guidelines for the treatment of HCC published by the APASL has been discussed. This latest guidelines recommend evidence-based management of HCC and are considered suitable for universal use in the Asia–Pacific region, which has a diversity of medical environments.


PLOS ONE | 2013

Metformin, a Diabetes Drug, Eliminates Tumor-Initiating Hepatocellular Carcinoma Cells

Tomoko Saito; Tetsuhiro Chiba; Kaori Yuki; Yoh Zen; Motohiko Oshima; Shuhei Koide; Tenyu Motoyama; Sadahisa Ogasawara; Eiichiro Suzuki; Yoshihiko Ooka; Akinobu Tawada; Motohisa Tada; Fumihiko Kanai; Yuichi Takiguchi; Atsushi Iwama; Osamu Yokosuka

Metformin has been widely used as an oral drug for diabetes mellitus for approximately 60 years. Interestingly, recent reports showed that metformin exhibited an anti-tumor action in a wide range of malignancies including hepatocellular carcinoma (HCC). In the present study, we investigated its impact on tumor-initiating HCC cells. Metformin suppressed cell growth and induced apoptosis in a dose-dependent manner. Flow cytometric analysis showed that metformin treatment markedly reduced the number of tumor-initiating epithelial cell adhesion molecule (EpCAM)+ HCC cells. Non-adherent sphere formation assays of EpCAM+ cells showed that metformin impaired not only their sphere-forming ability, but also their self-renewal capability. Consistent with this, immunostaining of spheres revealed that metformin significantly decreased the number of component cells positive for hepatic stem cell markers such as EpCAM and α-fetoprotein. In a xenograft transplantation model using non-obese diabetic/severe combined immunodeficient mice, metformin and/or sorafenib treatment suppressed the growth of tumors derived from transplanted HCC cells. Notably, the administration of metformin but not sorafenib decreased the number of EpCAM+ cells and impaired their self-renewal capability. As reported, metformin activated AMP-activated protein kinase (AMPK) through phosphorylation; however its inhibitory effect on the mammalian target of rapamycin (mTOR) pathway did not necessarily correlate with its anti-tumor activity toward EpCAM+ tumor-initiating HCC cells. These results indicate that metformin is a promising therapeutic agent for the elimination of tumor-initiating HCC cells and suggest as-yet-unknown functions other than its inhibitory effect on the AMPK/mTOR pathway.


Oncology | 2014

Efficacy of Sorafenib in Intermediate-Stage Hepatocellular Carcinoma Patients Refractory to Transarterial Chemoembolization

Sadahisa Ogasawara; Tetsuhiro Chiba; Yoshihiko Ooka; Naoya Kanogawa; Tenyu Motoyama; Eiichiro Suzuki; Akinobu Tawada; Fumihiko Kanai; Masaharu Yoshikawa; Osamu Yokosuka

Objective: We compared the benefits of sorafenib therapy with continued transarterial chemoembolization (TACE) in TACE-refractory patients with intermediate-stage hepatocellular carcinoma (HCC). Methods: This retrospective study reviewed intermediate-stage HCC patients who underwent the first TACE. Patients were defined as TACE-refractory and divided into two cohorts: (1) patients who switched from TACE to sorafenib and (2) those who continued TACE. We evaluated the patient overall survival (OS) and time to disease progression (TTDP; the time patients reached Child-Pugh C or developed advanced-stage HCC). Results: A total of 509 patients with HCC underwent TACE. Of 249 intermediate-stage HCC patients undergoing the first TACE, 122 were deemed refractory. At the time they were identified as refractory, 20 patients converted to sorafenib, whereas 36 patients continued TACE. We excluded patients with Child-Pugh scores of ≥8, those with advanced-stage HCC, those who had undergone hepatic arterial infusion chemotherapy or other systemic therapy, and those treated with best supportive care alone. The median TTDP and OS were 22.3 and 25.4 months, respectively, in the conversion group, and 7.7 and 11.5 months, respectively, in the continued group (p = 0.001 and p = 0.003, respectively). Conclusions: It is possible that sorafenib conversion might prolong OS and TTDP in TACE-refractory patients with intermediate-stage HCC.


PLOS ONE | 2014

Disulfiram Eradicates Tumor-Initiating Hepatocellular Carcinoma Cells in ROS-p38 MAPK Pathway-Dependent and -Independent Manners

Tetsuhiro Chiba; Eiichiro Suzuki; Kaori Yuki; Yoh Zen; Motohiko Oshima; Satoru Miyagi; Atsunori Saraya; Shuhei Koide; Tenyu Motoyama; Sadahisa Ogasawara; Yoshihiko Ooka; Akinobu Tawada; Tetsuya Nakatsura; Takehiro Hayashi; Taro Yamashita; Syuichi Kaneko; Masaru Miyazaki; Atsushi Iwama; Osamu Yokosuka

Tumor-initiating cells (TICs) play a central role in tumor development, metastasis, and recurrence. In the present study, we investigated the effect of disulfiram (DSF), an inhibitor of aldehyde dehydrogenase, toward tumor-initiating hepatocellular carcinoma (HCC) cells. DSF treatment suppressed the anchorage-independent sphere formation of both HCC cells. Flow cytometric analyses showed that DSF but not 5-fluorouracil (5-FU) drastically reduces the number of tumor-initiating HCC cells. The sphere formation assays of epithelial cell adhesion molecule (EpCAM)+ HCC cells co-treated with p38-specific inhibitor revealed that DSF suppresses self-renewal capability mainly through the activation of reactive oxygen species (ROS)-p38 MAPK pathway. Microarray experiments also revealed the enrichment of the gene set involved in p38 MAPK signaling in EpCAM+ cells treated with DSF but not 5-FU. In addition, DSF appeared to downregulate Glypican 3 (GPC3) in a manner independent of ROS-p38 MAPK pathway. GPC3 was co-expressed with EpCAM in HCC cell lines and primary HCC cells and GPC3-knockdown reduced the number of EpCAM+ cells by compromising their self-renewal capability and inducing the apoptosis. These results indicate that DSF impaired the tumorigenicity of tumor-initiating HCC cells through activation of ROS-p38 pathway and in part through the downregulation of GPC3. DSF might be a promising therapeutic agent for the eradication of tumor-initiating HCC cells.


Magnetic Resonance Imaging | 2013

Gadoxetic acid-enhanced MRI compared with CT during angiography in the diagnosis of hepatocellular carcinoma

Yoshihiko Ooka; Fumihiko Kanai; Shinichiro Okabe; Takuya Ueda; Ryota Shimofusa; Sadahisa Ogasawara; Tetsuhiro Chiba; Yasunori Sato; Masaharu Yoshikawa; Osamu Yokosuka

PURPOSE To assess the value of gadoxetic acid-enhanced magnetic resonance imaging (MRI) for the pre-therapeutic detection of hepatocellular carcinoma (HCC) using receiver operating characteristic (ROC) analysis with the combination of computed tomography (CT) arterial portography and CT hepatic arteriography (CTAP/CTHA). MATERIALS AND METHODS A total of 54 consecutive patients with 87 nodular HCCs were retrospectively analyzed. All HCC nodules were confirmed pathologically. Three blinded readers independently reviewed 432 hepatic segments, including 78 segments with 87 HCCs. Each reader read two sets of images: Set 1, CTAP/CTHA; Set 2, gadoxetic acid-enhanced MRI including a gradient dual-echo sequence and diffusion-weighted imaging (DWI). The ROC method was used to analyze the results. The sensitivity, specificity, positive predictive value, negative predictive value and sensitivity according to tumor size were evaluated. RESULTS For each reader, the area under the curve was significantly higher for Set 2 than for Set 1. The mean area under the curve was also significantly greater for Set 2 than for Set 1 (area under the curve, 0.98 vs. 0.93; P=.0009). The sensitivity was significantly higher for Set 2 than for Set 1 for all three readers (P=.012, .013 and .039, respectively). The difference in the specificity, positive predictive values and negative predictive values of the two modalities for each reader was not significant (P>.05). CONCLUSION Gadoxetic acid-enhanced MRI including a gradient dual-echo sequence and DWI is recommended for the pre-therapeutic evaluation of patients with HCC.


Journal of Gastroenterology and Hepatology | 2015

Sustained virologic response achieved after curative treatment of hepatitis C virus-related hepatocellular carcinoma as an independent prognostic factor.

Naoya Kanogawa; Sadahisa Ogasawara; Tetsuhiro Chiba; Tomoko Saito; Tenyu Motoyama; Eiichiro Suzuki; Yoshihiko Ooka; Akinobu Tawada; Tatsuo Kanda; Shigeru Mikami; Ryosaku Azemoto; Takashi Kaiho; Masami Shinozaki; Masayuki Ohtsuka; Masaru Miyazaki; Osamu Yokosuka

Whether an antiviral interferon (IFN)‐based therapy (IBT) after curative treatment of hepatocellular carcinoma (HCC) improves the prognosis in patients with hepatitis C virus (HCV)‐related HCC remains to be elucidated.


International Journal of Medical Sciences | 2014

Effect of Previous Interferon-based Therapy on Recurrence after Curative Treatment of Hepatitis C Virus-related Hepatocellular Carcinoma

Tomoko Saito; Tetsuhiro Chiba; Eiichiro Suzuki; Masami Shinozaki; Nobuaki Goto; Naoya Kanogawa; Tenyu Motoyama; Sadahisa Ogasawara; Yoshihiko Ooka; Akinobu Tawada; Tatsuo Kanda; Masaru Miyazaki; Osamu Yokosuka

Previous reports have shown that interferon (IFN)-based therapy decreases the risk of development of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C virus (HCV) infection. However, it remains to be fully elucidated whether elimination of HCV by IFN-based therapy inhibits HCC recurrence after curative treatment, such as surgical resection and local ablation therapies. In this study, we aimed to clarify the influence of a sustained virological response (SVR) after IFN-based therapy on recurrence and survival after curative treatment of HCC. Fifty-one patients who underwent curative treatment of HCV-related HCC after receiving IFN-based therapy were analyzed retrospectively. They were classified into SVR (N = 14) and non-SVR groups (N = 37). In the SVR group, serum levels of aspartate aminotransferase and alanine aminotransferase, the indocyanine green retention rate at 15 min, and the percentages of patients with liver cirrhosis and HCV serotype 1 were significantly lower, whereas serum albumin level and platelet count were significantly higher upon HCC occurrence. Recurrence-free survival (RFS) for the first recurrence was significantly higher in the SVR group (P < 0.01). Multivariate analysis showed that SVR at initial HCC treatment (P < 0.01) and multiple tumors (P < 0.01) are prognostic factors for RFS. Moreover, RFS for the second recurrence showed a similar trend to that for the first recurrence. In conclusion, patients who underwent IFN-based therapy before initial curative treatment of HCC had a favorable clinical outcome compared with non-SVR patients.


PLOS ONE | 2015

A prognostic score for patients with intermediate-stage hepatocellular carcinoma treated with transarterial chemoembolization.

Sadahisa Ogasawara; Tetsuhiro Chiba; Yoshihiko Ooka; Naoya Kanogawa; Tenyu Motoyama; Eiichiro Suzuki; Akinobu Tawada; Ryosaku Azemoto; Masami Shinozaki; Masaharu Yoshikawa; Osamu Yokosuka

Background Intermediate-stage hepatocellular carcinoma (HCC), defined according to the Barcelona Clinic Liver Cancer (BCLC) staging system, is a heterogeneous condition with variable clinical benefits from transarterial chemoembolization (TACE). This study aimed to develop a simple validated prognostic score based on the predictive factors for survival in patients with intermediate-stage HCC treated with TACE. Methods Three-hundred and fifty patients with intermediate-stage HCC undergoing initial TACE at Chiba University Hospital (training cohort; n = 187) and two affiliated hospitals (validation cohort; n = 163) were included. Following variables were entered into univariate and multivariate Cox regression models to develop a points-based clinical scoring system: gender, age, etiology, pretreatment, Child–Pugh score, aspartate aminotransferase, creatinine, C-reactive protein, alfa-fetoprotein, size of the largest lesion, and number and location of lesions. Results The number of lesions and the Child–Pugh score were identified as independent prognostic factors in the training cohort. The development of a 0–7-point prognostic score, named the Chiba HCC in intermediate-stage prognostic (CHIP) score, was based on the sum of three subscale scores (Child–Pugh score = 0, 1, 2, or 3, respectively, number of lesions = 0, 2, or 3, respectively, HCV-RNA positivity = 0 or 1, respectively). The generated scores were then differentiated into five groups (0–2 points, 3 points, 4 points, 5 points, and 6–7 points) by the median survival time (65.2, 29.2, 24.3, 13.1, and 8.4 months, respectively; p < 0.0001). These results were confirmed in the external validation cohort (p < 0.0001). Conclusions The CHIP score is easy-to-use and may assist in finding an appropriate treatment strategy for intermediate-stage HCC.


Lancet Oncology | 2018

Pembrolizumab in patients with advanced hepatocellular carcinoma previously treated with sorafenib (KEYNOTE-224): a non-randomised, open-label phase 2 trial

Andrew X. Zhu; Richard S. Finn; Julien Edeline; Stéphane Cattan; Sadahisa Ogasawara; Daniel H. Palmer; Chris Verslype; Vittorina Zagonel; Laetitia Fartoux; Arndt Vogel; Debashis Sarker; Gontran Verset; Stephen L. Chan; Jennifer J. Knox; Bruno Daniele; Andrea L. Webber; Scot Ebbinghaus; Junshui Ma; Abby B. Siegel; Ann-Lii Cheng; Masatoshi Kudo; Angela Tatiana Alistar; Jamil Asselah; Jean-Frédéric Blanc; Ivan Borbath; Timothy Cannon; Ki Chung; Allen Lee Cohn; David Cosgrove; Nevena Damjanov

BACKGROUND Immune checkpoint blockade therapy has shown promising results in patients with advanced hepatocellular carcinoma. We aimed to assess the efficacy and safety of pembrolizumab in this patient population. METHODS KEYNOTE-224 is a non-randomised, multicentre, open-label, phase 2 trial that is set in 47 medical centres and hospitals across ten countries. Eligible patients had pathologically confirmed hepatocellular carcinoma; had previously been treated with sorafenib and were either intolerant to this treatment or showed radiographic progression of their disease after treatment; an Eastern Cooperative Oncology Group performance status of 0-1; adequate organ function, and were Child-Pugh class A. Participants received 200 mg pembrolizumab intravenously every 3 weeks for about 2 years or until disease progression, unacceptable toxicity, patient withdrawal, or investigator decision. The primary endpoint was objective response, defined as the proportion of patients with complete or partial response in all patients who received at least one dose of pembrolizumab, which was radiologically confirmed by use of the Response Evaluation Criteria in Solid Tumors version 1.1 by central review. Safety was also assessed in all treated patients. This trial is ongoing but closed to enrolment and is registered with ClinicalTrials.gov number NCT02702414. FINDINGS Between June 7, 2016, and Feb 9, 2017, we screened 169 patients with advanced hepatocellular carcinoma, of whom 104 eligible patients were enrolled and treated. As of data cutoff on Feb 13, 2018, 17 (16%) patients were still receiving pembrolizumab. We recorded an objective response in 18 (17%; 95% CI 11-26) of 104 patients. The best overall responses were one (1%) complete and 17 (16%) partial responses; meanwhile, 46 (44%) patients had stable disease, 34 (33%) had progressive disease, and six (6%) patients who did not have a post-baseline assessment on the cutoff date were considered not to be assessable. Treatment-related adverse events occurred in 76 (73%) of 104 patients, which were serious in 16 (15%) patients. Grade 3 treatment-related events were reported in 25 (24%) of the 104 patients; the most common were increased aspartate aminotransferase concentration in seven (7%) patients, increased alanine aminotransferase concentration in four (4%) patients, and fatigue in four (4%) patients. One (1%) grade 4 treatment-related event of hyperbilirubinaemia occurred. One death associated with ulcerative oesophagitis was attributed to treatment. Immune-mediated hepatitis occurred in three (3%) patients, but there were no reported cases of viral flares. INTERPRETATION Pembrolizumab was effective and tolerable in patients with advanced hepatocellular carcinoma who had previously been treated with sorafenib. These results indicate that pembrolizumab might be a treatment option for these patients. This drug is undergoing further assessment in two phase 3, randomised trials as a second-line treatment in patients with hepatocellular carcinoma. FUNDING Merck & Co, Inc.

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