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Featured researches published by Akihiro Murata.


BMC Cancer | 2013

IGF-1 receptor and IGF binding protein-3 might predict prognosis of patients with resectable pancreatic cancer

Toshiki Hirakawa; Masakazu Yashiro; Akihiro Murata; Keiichiro Hirata; Kenjiro Kimura; Ryosuke Amano; Nobuya Yamada; Bunzo Nakata; Kosei Hirakawa

BackgroundThe present study aimed to elucidate the clinicopathologic role of insulin-like growth factor-1 receptor (IGF1R) and IGF binding protein-3 (IGFBP3) in patients with pancreatic cancer. The function of IGFBP3 is controversial, because both inhibition and facilitation of the action of IGF as well as IGF-independent effects have been reported. In this study, IGF1R and IGFBP3 expression was examined, and their potential roles as prognostic markers in patients with pancreatic cancer were evaluated.MethodsClinicopathological features of 122 patients with curatively resected pancreatic cancer were retrospectively reviewed, and expression of IGF1R and IGFBP3 was immunohistochemically analyzed.ResultsExpression of IGF1R and IGFBP3 was observed in 50 (41.0%) and 37 (30.3%) patients, respectively. IGF1R expression was significantly associated with histological grade (p = 0.037). IGFBP3 expression had a significant association with tumor location (p = 0.023), and a significant inverse association with venous invasion (p = 0.037). Tumors with IGF1R-positive and IGFBP3-negative expression (n = 32) were significantly frequently Stage II and III (p = 0.011). The prognosis for IGF1R positive patients was significantly poorer than that for IGF1R negative patients (p = 0.0181). IGFBP3 protein expression did not correlate significantly with patient survival. The subset of patients with both positive IGF1R and negative IGFBP3 had worse overall survival (8.8 months versus 12.6 months, respectively, p < 0.001).ConclusionIGF1R signaling might be associated with tumor aggressiveness, and IGFBP3 might show antiproliferative effects in pancreatic cancer. Both high IGF1R expression and low IGFBP3 expression represent useful prognostic markers for patients with curatively resected pancreatic cancer.


World Journal of Surgical Oncology | 2014

Clinical and pathological features of five-year survivors after pancreatectomy for pancreatic adenocarcinoma

Kenjiro Kimura; Ryosuke Amano; Bunzo Nakata; Sadaaki Yamazoe; Keiichiro Hirata; Akihiro Murata; Kotaro Miura; Kohei Nishio; Toshiki Hirakawa; Masaichi Ohira; Kosei Hirakawa

BackgroundClinical factors determining short-term survival after pancreatectomy have been well studied, but factors predicting long-term survival with curative resection are poorly understood in pancreatic carcinoma. Our objective was to identify clinical and pathological features of five-year disease-free survivors after surgical resection of pancreatic adenocarcinoma.MethodsThe clinical and pathological data from 147 patients who underwent a potentially curative resection for pancreatic adenocarcinoma at our institution between 1988 and 2012 were retrospectively analyzed.ResultsOf 147 patients, 18 survived for more than five years after surgery without disease recurrence. A univariate analyses demonstrated that: two or fewer lymph node metastases (P = 0.014), a preoperative serum carbohydrate antigen 19-9 (CA19-9) level of 40 U/mL or less (P = 0.0018), an absence of intrapancreatic nerve invasion (P = 0.028), and undergoing an R0 resection (P = 0.011) were significantly associated with five-year survival. A logistic regression model identified the following independent cancer-related predictors of five-year survivors: having two or fewer lymph node metastases (odds ratio (OR): 6.02; 95% confidence interval (CI): 1.08 to 112.98; P = 0.0385), a preoperative serum CA19-9 level of 40 U/mL or less (OR: 5.02; 95% CI: 1.68 to 16.48; P = 0.0036), and undergoing an R0 resection (OR: 3.63; 95% CI: 1.12 to 14.28; P = 0.0316).ConclusionsWe conclude that number of lymph node metastases being two or less, a preoperative serum CA19-9 level of 40 U/mL or less, and undergoing an R0 resection may be independent predictive factors to identify actual five-year survivors after pancreatectomy for pancreatic adenocarcinoma.


World Journal of Surgical Oncology | 2013

Prognostic predictive values of gemcitabine sensitivity-related gene products for unresectable or recurrent biliary tract cancer treated with gemcitabine alone

Akihiro Murata; Ryosuke Amano; Nobuya Yamada; Kenjiro Kimura; Masakazu Yashiro; Bunzo Nakata; Kosei Hirakawa

BackgroundGemcitabine is a pyrimidine nucleoside analog that is a commonly used chemotherapeutic agent for unresectable or recurrent biliary tract cancer (BTC). Several molecules involved in gemcitabine metabolism, including human equilibrative nucleoside transporter (hENT1), deoxycytidine kinase (dCK), and ribonucleotide reductase subunit M1 (RRM1), have been investigated as predictive biomarkers of gemcitabine efficacy, mostly in pancreatic cancer. The aim of this study is to clarify which biomarker is the most reliable among hENT1, dCK, and RRM1 to predict survival in patients with advanced BTC treated with gemcitabine alone.MethodsThe analysis was performed on samples from 28 patients with unresectable or recurrent BTC who were treated with gemcitabine alone as first-line therapy. The starting date of overall survival (OS) and progression-free survival (PFS) was defined as the date of first treatment with gemcitabine. Intratumoral hENT1, dCK, and RRM1 expressions were examined by immunohistochemistry.ResultsThe expressions of hENT1, dCK, and RRM1 had no significant relationships with age, gender, primary tumor site, recurrence/unresectable, or histological type. Among the three molecules, only hENT1 expression was a significant factor affecting OS and PFS in univariate analysis; OS was 11.4 months for high hENT1 expression versus 5.7 months for low, P = 0.0057; PFS was 7.7 months for high versus 2.5 months for low, P = 0.0065. Multivariate analyses also identified hENT1 expression as an independent predictive factor for OS.ConclusionshENT1 is the most reliable predictive marker of survival in patients with advanced BTC treated with gemcitabine.


Hepato-gastroenterology | 2013

MUC1 and HER2 might be associated with invasive phenotype of intraductal papillary mucinous neoplasm.

Ohira G; Kenjiro Kimura; Nobuya Yamada; Ryosuke Amano; Bunzo Nakata; Yosuke Doi; Akihiro Murata; Masakazu Yashiro; Tanaka S; Masahiko Ohsawa; Kenichi Wakasa; Kosei Hirakawa

BACKGROUND/AIMS The purpose of this study was to clarify the biomarkers which distinguish invasive Intraductal papillary mucinous neoplasms (IPMNs) from noninvasive IPMNs. METHODOLOGY In tumor specimens from sixty patients with IPMNs (42 noninvasive IPMNs and 18 invasive IPMNs) who underwent surgical resection at our institute, we analyzed the correlation between the immunohistochemical expression level of MUC1, MUC2, MUC4, MUC5AC, p53, VEGFR2, HER2, and HER3. RESULTS The 5-year survival rate was 100% in noninvasive IPMNs, while that of invasive IPMNs was only 36.5%. MUC1, MUC4, HER2 and HER3 were significantly associated with invasive IPMNs in univariate analysis. Multivariate analysis revealed that MUC1 and HER2 were significantly associated with invasive IPMNs. The 5-year survival of IPMN patients with either MUC1-positive and/or HER2-positive (54.5%) is significantly poorer than that of IPMN patients with MUC1 negative and HER2 negative (100%). CONCLUSIONS MUC1 and HER2 might be closely associated with invasive phenotype of IPMNs.


Hepato-gastroenterology | 2013

In vitro effects of lapatinib with gemcitabine for pancreatic cancer cells.

Akihiro Murata; Bunzo Nakata; Komoto M; Koichi Hirata; Kenjiro Kimura; Ryosuke Amano; Kosei Hirakawa

BACKGROUND/AIMS We investigated whether lapatinib plus gemcitabine has synergistic or antagonistic effects on the pancreatic cancer cell lines MiaPaca-2 and PANC-1. Furthermore, the changes of gemcitabine sensitivity-related genes by lapatinib treatment were examined. METHODOLOGY The effects of lapatinib, gemcitabine, and combined treatment with both agents on cell viability were examined by methyl thiazolyl tetrazolium analysis. Synergy between lapatinib and gemcitabine was assessed by median effect analysis. The mRNA amounts of human equilibrative nucleoside transporter (hENT1), deoxycytidine kinase (dCK) and ribonucleotide reductase subunit M1 (RRM1) genes were measured by quantitative real-time polymerase chain reaction in cells exposed to lapatinib for 48 h, as compared with untreated cells. RESULTS No synergistic effects were observed with combined treatment in either cell line. In contrast, antagonistic effects occurred on MiaPaca-2 cells with the two agents. Specific changes in gemcitabine sensitivity-related genes induced by lapatinib were not detected in either MiaPaca-2 or PANC-1. CONCLUSIONS Lapatinib may not enhance the anti-tumor effects of gemcitabine for pancreatic cancer.


Cancer Research | 2012

Abstract 711: The expression of human equilibrative nucleoside transporter 1 (hENT1) is associated with overall survival in advanced biliary tract carcinoma (BTC) treated with gemcitabine

Akihiro Murata; Ryousuke Amano; Kenjiro Kimura; Nobuya Yamada; Bunzo Nakata; Hisashi Nagahara; Eiji Noda; Naoshi Kubo; Hiroaki Tanaka; Kazuya Muguruma; Masakazu Yashiro; Kiyoshi Maeda; Masaichi Ohira; Tetsurou Ishikawa; Kosei Hirakawa

[Introduction] The outcome of patients with unresectable and postoperative recurrent biliary tract carcinoma (BTC) is mostly miserable and most patients are possible candidates for palliative chemotherapy. Gemcitabine is a pyrimidine nucleoside analogue that is commonly used chemotherapeutic agent for advanced BTC. Gemcitabine is transported into the cell mostly by human equilibrative nucleoside transporter 1(hENT1). The hENT1 expression has been demonstrated to play an important role in predicting clinical outcome after gemcitabine chemotherapy for several types of cancer. The aim of the present study was to investigate a predictive marker for good prognosis of gemcitabine chemotherapy for unresectable and postoperative recurrent BTC. [Materials and methods] The analysis was performed on samples from 25 patients with unresectable (6 patients) and postoperative recurrent (19 patients) BTC treated with gemcitabine at the host institute between January 1997 and January 2011. The hENT1 expression levels in tumors were evaluated by immunohistochemistry. The clinical and histopathological variables were analyzed to evaluate predictive values for survival. [Results] Of the 25 tumor specimens, 18 (72%) specimens had positive hNET1 immunostaing, while 7 (28%) specimens were classified as negative. No statistical significant differences were found between the expression of hENT1 and patient characteristics (gender, age, tumor stage, lymph node stage, lymph duct invasion, vascular invasion, perineural invasion). In the univariate analysis, hENT1 expression was significantly correlated with overall survival (OS). The median OS was 15.3 versus 4.2 months, respectively in patients with positive versus negative hENT1 staining (p=0.006). As a result of multivariate analysis, hENT1 expression was useful as a predictive marker for good prognosis with significant difference (p Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 711. doi:1538-7445.AM2012-711


BMC Research Notes | 2014

Early gastric cancer with suspected brain metastasis arising eight years after curative resection: a case report

Katsunobu Sakurai; Kazuya Muguruma; Akihiro Murata; Takahiro Toyokawa; Ryosuke Amano; Naoshi Kubo; Hiroaki Tanaka; Masakazu Yashiro; Kiyoshi Maeda; Masaichi Ohira; Kosei Hirakawa


BMC Cancer | 2016

Establishment and characterization of new cell lines of anaplastic pancreatic cancer, which is a rare malignancy: OCUP-A1 and OCUP-A2

Kotaro Miura; Kenjiro Kimura; Ryosuke Amano; Sadaaki Yamazoe; Go Ohira; Akihiro Murata; Kohei Nishio; Tsuyoshi Hasegawa; Masakazu Yashiro; Bunzo Nakata; Masaichi Ohira; Kosei Hirakawa


Surgery: Current Research | 2015

Evaluation of the Prognostic Significance of 'High-risk Stigmata' in the International Consensus Guidelines 2012 for Intraductal Papillary Mucinous Neoplasm

Kenjiro Kimura; Ryosuke Amano; Sadaaki Yamazoe; Go Ohira; Kotaro Miura; Kohei Nishio; Katsunobu Sakurai; Takahiro Toyokawa; Bunzo Nakata; Akihiro Murata; Sadatoshi Shimizu; Sayaka Tanaka; Masahiko Ohsawa; Masaichi Ohira; Kosei Hirakawa


Hepato-gastroenterology | 2015

Two-surgeon technique for liver transection using precoagulation by a soft-coagulation system and ultrasonic dissection.

Nobuya Yamada; Ryosuke Amano; Kenjiro Kimura; Akihiro Murata; Masakazu Yashiro; Tanaka S; Kenichi Wakasa; Kosei Hirakawa

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