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Dive into the research topics where Ken Tanikawa is active.

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Featured researches published by Ken Tanikawa.


The American Journal of Surgical Pathology | 2013

Clinicopathologic analysis of combined hepatocellular-cholangiocarcinoma according to the latest WHO classification.

Jun Akiba; Osamu Nakashima; Satoshi Hattori; Ken Tanikawa; Miki Takenaka; Masamich Nakayama; Reiichiro Kondo; Yoriko Nomura; Keiko Koura; Kousuke Ueda; Sakiko Sanada; Yoshiki Naito; Rin Yamaguchi; Hirohisa Yano

Combined hepatocellular-cholangiocarcinoma comprises <1% of all liver carcinomas. The histogenesis of combined hepatocellular-cholangiocarcinoma has remained unclear for many years. However, recent advances in hepatic progenitor cell (HPC) investigations have provided new insights. The concept that combined hepatocellular-cholangiocarcinoma originates from HPCs is adopted in the chapter “combined hepatocellular-cholangiocarcinoma” of the latest World Health Organization (WHO) classification. In this study, we conducted clinicopathologic analysis of combined hepatocellular-cholangiocarcinoma according to the latest WHO classification. Fifty-four cases were included in this study. Pathologic diagnosis was made according to the WHO classification. When a tumor contained plural histologic patterns, predominant histologic pattern (≥50%) was defined. Minor histologic patterns were also appended. Immunohistochemical staining with biliary markers (CK7, CK19, and EMA), hepatocyte paraffin (HepPar)-1, HPC markers (CD56, c-kit, CD133, and EpCAM), and vimentin was performed. Forty-five and 50 patients were analyzed for progression-free survival and overall survival, respectively. Ten, 1, 32, and 11 cases were diagnosed as: combined hepatocellular-cholangiocarcinoma, classical type; combined hepatocellular-cholangiocarcinoma, stem cell features, typical subtype; combined hepatocellular-cholangiocarcinoma, stem cell features, intermediate cell subtype; and combined hepatocellular-cholangiocarcinoma, stem cell features, cholangiolocellular type, respectively. Combined hepatocellular-cholangiocarcinomas usually have high expression of biliary markers. CD56, c-kit, and EpCAM were expressed to various degrees in all combined hepatocellular-cholangiocarcinomas apart from the hepatocellular carcinoma component of combined hepatocellular-cholangiocarcinoma, classical type. The expression of CD133 and vimentin was observed only in combined hepatocellular-cholangiocarcinoma, stem cell features of intermediate cell subtype and cholangiolocellular subtype. The expression of CD133, EpCAM, and vimentin was significantly high in combined hepatocellular-cholangiocarcinoma, subtypes with stem cell features, especially cholangiolocellular subtype. Minor histologic patterns were significantly frequent in combined hepatocellular-cholangiocarcinoma, subtypes with stem cell features, compared with combined hepatocellular-cholangiocarcinoma, classical type. There was no significant difference in clinical outcome between each subtype. Combined hepatocellular-cholangiocarcinoma has wide histologic diversity and shows immunophenotypic expression of not only biliary markers but also HPC markers to various degrees, suggesting that the histogenesis of combined hepatocellular-cholangiocarcinoma could be strongly associated with HPCs. Our results pathologically validate the latest WHO classification of combined hepatocellular-cholangiocarcinoma. However, the complex mixture of histologic subtypes has presented a challenge to the classification of combined hepatocellular-cholangiocarcinoma. Further study should be conducted using a large cohort to support this classification.


The Journal of Pediatrics | 2014

Improved liver function and relieved pruritus after 4-phenylbutyrate therapy in a patient with progressive familial intrahepatic cholestasis type 2.

Sotaro Naoi; Hisamitsu Hayashi; Takeshi Inoue; Ken Tanikawa; Koji Igarashi; Hironori Nagasaka; Masayoshi Kage; Hajime Takikawa; Yuichi Sugiyama; Ayano Inui; Toshiro Nagai; Hiroyuki Kusuhara

To examine the effects of 4-phenylbutyrate (4PB) therapy in a patient with progressive familial intrahepatic cholestasis type 2. A homozygous c.3692G>A (p.R1231Q) mutation was identified in ABCB11. In vitro studies showed that this mutation decreased the cell-surface expression of bile salt export pump (BSEP), but not its transport activity, and that 4PB treatment partially restored the decreased expression of BSEP. Therapy with 4PB had no beneficial effect for 1 month at 200 mg/kg/day and the next month at 350 mg/kg/day but partially restored BSEP expression at the canalicular membrane and significantly improved liver tests and pruritus at a dosage of 500 mg/kg/day. We conclude that 4PB therapy would have a therapeutic effect in patients with progressive familial intrahepatic cholestasis type 2 who retain transport activity of BSEP per se.


Journal of Gastroenterology | 2013

Accumulation of platelets in the liver may be an important contributory factor to thrombocytopenia and liver fibrosis in chronic hepatitis C

Reiichiro Kondo; Hirohisa Yano; Osamu Nakashima; Ken Tanikawa; Yoriko Nomura; Masayoshi Kage

BackgroundThrombocytopenia is a marked feature of chronic liver disease and cirrhosis. We tried to clarify whether an accumulation of platelets in the liver contributes to thrombocytopenia and liver fibrosis in chronic liver disease.MethodsThirty-eight patients who underwent hepatectomy for hepatocellular carcinoma (HCC) with hepatitis C virus infection were included. The locations of platelets and Kupffer cells and the expression of platelet-derived growth factor (PDGF) receptor-β and smooth muscle actin (SMA) were identified by immunohistochemistry. Perisinusoidal mesenchymal cells that express PDGF receptor-β and SMA were interpreted as transformed hepatic stellate cells (HSCs).ResultsPatients with cirrhosis had a more extensive platelet area in the liver compared to controls (5601xa0±xa05611 vs. 564xa0±xa0361xa0μm2, pxa0=xa00.02), although the blood platelet count significantly decreased along with the progression of liver fibrosis. In cirrhotic liver, most platelets were present in the sinusoidal space of the periportal area with inflammation, where HSCs expressing PDGF receptor-β were frequently observed. In addition, the platelet and Kupffer cell areas were significantly smaller in cancerous tissue than those in noncancerous tissues (platelet area: 492xa0±xa0823 vs. 3643xa0±xa04055xa0μm2, pxa0=xa00.001; Kupffer cell area: 450xa0±xa0841 vs. 3012xa0±xa03051xa0μm2, pxa0=xa00.001).ConclusionsThe accumulation of platelets in the liver with chronic hepatitis may be involved in thrombocytopenia and liver fibrosis through the activation of HSCs. In addition, our findings also indicate that both platelets and Kupffer cells decrease in HCC tissues.


Phytomedicine | 2010

The antioxidant effect of green tea catechin ameliorates experimental liver injury

Hidefumi Kobayashi; Yoshiaki Tanaka; Kimio Asagiri; Takahiro Asakawa; Ken Tanikawa; Masayoshi Kage; Minoru Yagi

PURPOSEnSeveral studies have reported green tea catechin to have both antifibrotic and anti-oxidative effects. The goal of this study was to evaluate the effect of green tea cathechin therapy in hepatic tissue injury using cholestatic rats with bile duct ligation.nnnMATERIALS AND METHODSnWe performed bile duct ligation on cholestatic seven-week-old male Wistar rats and classified them into three groups according to the method of treatment. The groups comprised the SHAM group, the NT-group (no-treatment-group), and the T-group (treatment-group). The rats were orally administered green tea catechin at a dose of 50mg/kg/day and were sacrificed on the 17th postoperative day. We subsequently investigated the levels of fibrosis and antioxidant activity associated with various clinical markers. We evaluated the serum AST and ALT levels and performed immunohistochemical analyses for 4-hydroxynonenal (4-HNE), 8-oxo-2deoxyguanosine (8-OHdG) and transforming growth factor-beta1 (TGF-beta1). We also evaluated the levels of activator protein-1 m-RNA (AP-1 m-RNA) and tissue inhibitor metalloproteinase-1 m-RNA (TIMP-1 m-RNA) by Real Time PCR. Finally, we performed Azan staining and immunohistochemical staining of alpha-smooth muscle actin (alpha-SMA) to evaluate the degree of fibrosis.nnnRESULTSnThe values of serum AST, serum ALT, AP-1 m-RNA, alpha-SMA, TGF-beta1, 4-HNE, and 8-OHdG in the T-Group were significantly lower than those in NT-Group. Therefore, the administration of green tea catechin might have suppressed the oxidative stress, controlled the stellate cell activation and consequently reduced the fibrosis.nnnCONCLUSIONnGreen tea catechin may reduce hepatic fibrosis by suppressing oxidative stress and controlling the transcription factor expression involved in stellate cell activation.


Hepatology Research | 2010

Histological findings in the livers of patients with neonatal intrahepatic cholestasis caused by citrin deficiency

Akihiko Kimura; Masayoshi Kage; Ikuo Nagata; Sotaro Mushiake; Toshihiro Ohura; Yusaku Tazawa; Shunichi Maisawa; Takeshi Tomomasa; Daiki Abukawa; Yoshiyuki Okano; Ryo Sumazaki; Masaki Takayanagi; Akiko Tamamori; Tohru Yorifuji; Yasuhiko Yamato; Kohji Maeda; Masami Matsushita; Toyojiro Matsuishi; Ken Tanikawa; Keiko Kobayashi; Takeyori Saheki

Aim:u2002 To characterize the histological features of the livers of patients with neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD), we studied specimens from 30 patients diagnosed with NICCD by genetically analyzing the SLC25A13 gene.


Hepatology Research | 2016

Successful treatment with 4‐phenylbutyrate in a patient with benign recurrent intrahepatic cholestasis type 2 refractory to biliary drainage and bilirubin absorption

Hisamitsu Hayashi; Sotaro Naoi; Yu Hirose; Yusuke Matsuzaka; Ken Tanikawa; Koji Igarashi; Hironori Nagasaka; Masayoshi Kage; Ayano Inui; Hiroyuki Kusuhara

Benign recurrent intrahepatic cholestasis type 2 (BRIC2) is caused by mutations in ABCB11, a gene encoding the bile salt export pump (BSEP) that mediates biliary bile salt secretion, and presents with repeated intermittent cholestasis with refractory itching. Currently, no effective medical therapy has been established. We previously provided experimental and clinical evidence suggesting the therapeutic potential of 4‐phenylbutyrate (4PB) for the cholestatic attacks of BRIC2.


Hepatology Research | 2014

Pathological characteristics of patients who develop hepatocellular carcinoma with negative results of both serous hepatitis B surface antigen and hepatitis C virus antibody

Reiichiro Kondo; Osamu Nakashima; Michio Sata; Fumio Imazeki; Osamu Yokosuka; Ken Tanikawa; Masayoshi Kage; Hirohisa Yano

We tried to characterize the pathological features of patients who developed hepatocellular carcinoma (HCC) with the negative results of both serous hepatitis B surface antigen and hepatitis C virus antibody (non‐B, non‐C).


Pediatric Surgery International | 2012

The herbal medicine Inchinko-to reduces hepatic fibrosis in cholestatic rats

Takahiro Asakawa; Minoru Yagi; Yoshiaki Tanaka; Kimio Asagiri; Hidefumi Kobayashi; Hideaki Egami; Ken Tanikawa; Masayoshi Kage

PurposeSeveral studies have reported the herbal medicine Inchinko-to (ICKT) to have an antifibrotic effect which thus leads to an improvement of hepatic injury. However, there are still few reports of its use in the treatment of cholestatic liver disorder. The aim of this study was to clarify whether the administration of ICKT will ameliorate hepatic fibrosis and injury in cholestatic rats.Materials and methodsWe performed bile duct ligation on 7-week-old male cholestatic Wistar rats and assigned them to one of three groups according to the method of treatment : (1) the SHAM group, (2) the NT-group (non-treatment group), and (3) the T-group (treatment-group). Rats in the T-group were orally administered ICKT (TJ-135) at a dose of 1xa0g/kg/day and were killed on the 17th postoperative day. We subsequently investigated the levels of fibrosis and various clinical markers through measurement of the following: serum levels of AST and ALT; tissue transforming growth factor-beta 1 (TGF-beta1); tissue inhibitor metalloprotease-1 mRNA (TIMP-1 mRNA) through real-time PCR analysis; and Azan staining and immunohistochemical staining of alfa-smooth muscle actin (alfa-SMA) to evaluate the degree of fibrosis.ResultsThe levels of serum AST, serum ALT, and TGF-bata1 in the T-Group were significantly lower than those in the NT-Group. In addition, staining of Azan and alfa-SMA in the T-Group was significantly lower than those in the NT-Group.ConclusionICKT may help reduce hepatic fibrosis and injury by controlling stellate cell activation.


Pediatric Surgery International | 2009

Oxidative stress profile in the post-operative patients with biliary atresia

Takahiro Asakawa; Yoshiaki Tanaka; Kimio Asagiri; Hidefumi Kobayashi; Ken Tanikawa; Minoru Yagi

Background and purposeMany post-operative patients with biliary atresia (BA) suffer from liver dysfunction, such as chronic inflammation even without jaundice after a Kasai’s hepatic portoenterostomy.MethodsThe presence and degree of oxidative stress were evaluated in the post-operative patients with BA. Twelve outpatients who underwent a Kasai’s hepatic portoenterostomy were evaluated. The active oxygen products, the rate of bioantioxidant, the markers of oxidative stress, and the degree of hepatic oxidative stress were examined by immunohistochemical staining of biopsied specimens.ResultsAll of the oxidative stress markers in the post-operative patients with BA increased in comparison to those in the controls. Moreover, 8-OHdG immunohistochemical staining was positive in 84xa0±xa04.8% in hepatic cells in the portal area in the post-operative patients with BA.ConclusionThe post-operative patients with BA were under increased oxidative stress, even if their liver dysfunction was mild without jaundice. Antioxidant therapy might be necessary to decrease of oxidative stress in the post-operative patients with BA.


Surgery Today | 2007

Mesenchymal Hamartoma of the Liver Accompanied by a Daughter Nodule: Report of a Case

Suguru Fukahori; Tomomitsu Tsuru; Ken Tanikawa; Kenjiro Akiyoshi; Kimio Asagiri; Yoshiaki Tanaka; Masayoshi Kage; Masamichi Kojiro; Hiroyoshi Mizote; Minoru Yagi

Mesenchymal hamartoma of the liver (MHL) is an uncommon benign tumor found primarily in children younger than 2 years of age. We report a rare case of MHL with a daughter nodule and atypical histological findings in a 14-month-old girl. On admission, computed tomography, magnetic resonance imaging, and angiography showed a solid hypovascular mass with a central cystic area in the liver. Laparotomy revealed a tumor, 8u2009cm in size, occupying segment 5 and parts of segments 4 and 6 of the liver, and a small nodule, 10u2009mm in size, in segment 7. Thus, we performed a partial hepatic resection (S4–6) and tumor extirpation (S7). The histological findings of both tumors were the same, but atypical of MHL. Recent studies on the pathogenesis of this tumor have found neoplastic features such as genetic anomalies and malignant transformation. These findings suggest that the conventional approach of completely resecting the tumor whenever possible is the best treatment.

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