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Featured researches published by Katsunobu Sakurai.


International Journal of Clinical Oncology | 2008

Androgen receptor expression in breast cancer: relationship with clinicopathological factors and biomarkers

Yoshinari Ogawa; Eishu Hai; Kanako Matsumoto; Katsumi Ikeda; Shinya Tokunaga; Hisashi Nagahara; Katsunobu Sakurai; Takeshi Inoue; Yukio Nishiguchi

BackgroundBreast cancer is a hormone-dependent tumor. Most breast cancer cells have an androgen receptor (AR), but the clinical value of AR expression is unclear.MethodsAR expression was evaluated in 227 primary breast cancers using immunohistochemistry. The relation of AR expression to clinicopathological factors and biomarkers was analyzed. AR expression was assessed semiquantitatively, and tumors with more than 10% of stained cells were regarded as positive.ResultsThe AR-positive rate was higher in smaller tumors (P = 0.045), tumors with negative lymph node metastasis (P = 0.045), scirrhous-type tumors (P < 0.0001), tumors of low histological grade (P = 0.0001), and p53-negative tumors (P = 0.0097). Although AR had no relation to menopausal status, 79% of cases of high AR expression (>50% stained cells) were in postmenopausal women. AR was related to estrogen receptor (ER; P = 0.027) and progesterone receptor (PR; P = 0.016) expression, but showed no relation to human epidermal growth factor receptor type 2 (Her2) expression. Regarding the coexpression of these receptors, 18 of the 42 cases of triple-negative (ER/ PR/ Her2-negative) tumors (43%) were AR-positive.ConclusionAR expression is related to low malignancy in breast cancer. The assessment of AR expression may lead to new treatment strategies for breast cancer, especially in postmenopausal women and in women with tumors that show triple negativity for hormone receptors.


PLOS ONE | 2015

Impact of the Preoperative Controlling Nutritional Status (CONUT) Score on the Survival after Curative Surgery for Colorectal Cancer.

Yasuhito Iseki; Masatsune Shibutani; Kiyoshi Maeda; Hisashi Nagahara; Hiroshi Ohtani; Kenji Sugano; Tetsuro Ikeya; Kazuya Muguruma; Hiroaki Tanaka; Takahiro Toyokawa; Katsunobu Sakurai; Kosei Hirakawa

Background Recently, the preoperative immune-nutritional status has been reported to correlate with the survival rate in patients with colorectal cancer (CRC). However, there have been no reports on the relationship between the controlling nutritional status (CONUT) score and the clinical outcome after curative surgery for CRC. We herein evaluated the prognostic significance of the CONUT score in patients with CRC, and then compared the accuracy of the CONUT score and the prognostic nutritional index (PNI) as a predictor of survival. Methods We retrospectively reviewed a database of 204 patients who underwent curative surgery for Stage II/III CRC. Patients were divided into two groups according to the CONUT score and the PNI. Results The five-year cancer-specific survival (CSS) rate was significantly higher at 92.7% in the low CONUT group, compared to a rate of 81.0% in the high CONUT group (p=0.0016). The five-year CSS was 71.2% in the low PNI group and 92.3% in the high PNI group, which showed a significant difference (p=0.0155). A multivariate analysis showed that lymph node metastasis and the CONUT score were independent risk factors for CSS. Conclusion This study suggested that the CONUT score is a strong independent predictor of the survival among CRC patients.


British Journal of Cancer | 2012

Expression of Forkhead box P3 in tumour cells causes immunoregulatory function of signet ring cell carcinoma of the stomach

Mami Yoshii; Hiroaki Tanaka; Masaichi Ohira; Kazuya Muguruma; Takehiko Iwauchi; Tin-Lap Lee; Katsunobu Sakurai; Naoshi Kubo; Masakazu Yashiro; Tomo Sawada; Hirakawa K

Background:It was recently reported that the transcription factor Forkhead box P3 (FoxP3) is expressed not only in regulatory T cells (Tregs) but also in cancer cells. The aim of this study was to clarify the clinical significance of FoxP3 expression in gastric carcinoma.Methods:We performed immunohistochemical staining of FoxP3 to examine the association of FoxP3 expression with clinicopathological features of 194 patients with gastric cancer who underwent surgical resection from 2000 to 2010. We also investigated the immunosuppressive function of FoxP3 using gastric cancer cell lines.Results:Immunohistochemical staining indicated FoxP3-positive cells within tumour tissue including both Tregs and tumour cells. Forkhead box P3-positive tumour cells were observed in 79.3% of signet ring cell carcinoma patients, and the expression of FoxP3 showed a significant correlation with lymph node metastasis. We showed that transforming growth factor-β augmented FoxP3 mRNA expression in cell lines derived from signet ring cell carcinoma. Indoleamine-2,3-dioxygenase and galectin-1, key effectors of Treg-mediated immunosuppression, were downregulated by FoxP3 knockdown.Conclusion:Our findings suggested that FoxP3 expression by tumour cells might have important roles in immune escape of gastric carcinoma, and be associated with the malignant potential of scirrhous gastric carcinoma.


Cancer Letters | 2014

Lysyl oxidase-like 2 (LOXL2) from stromal fibroblasts stimulates the progression of gastric cancer

Hiroaki Kasashima; Masakazu Yashiro; Haruhito Kinoshita; Tatsunari Fukuoka; Tamami Morisaki; Go Masuda; Katsunobu Sakurai; Naoshi Kubo; Masaichi Ohira; Kosei Hirakawa

The aim of this study was to clarify the role of fibroblast-derived Lysyl oxidase-like 2 (LOXL2) in the development of gastric cancer. The correlation between the clinicopathological features of 548 primary gastric carcinomas and LOXL2 expression in stromal cells was examined by immunohistochemistry. Two gastric cancer cell lines, OCUM-12 and NUGC-3, and cancer-associated fibroblasts (CAFs) were used in this in vitro study. The effect of fibroblast-derived LOXL2 on the motility of gastric cancer cells was analyzed by using a wound-healing assay, a double-chamber invasion assay, and western blot. LOXL2 expression in stromal cells was significantly associated with tumor invasion depth, lymph node metastasis, lymphatic invasion, venous invasion, and peritoneal dissemination. Multivariable logistic regression analysis revealed that LOXL2 expression in stromal cells could be an independent predictive parameter for the overall survival of patients. CAFs significantly stimulated the migration and invasion of OCUM-12 and NUGC-3 cells. This motility-stimulating ability of CAFs was inhibited by LOXL2 siRNA. Western blot analysis indicated that phosphorylation of focal adhesion kinase (FAK) in cancer cells was increased by the conditioned medium from CAFs, and was decreased by the conditioned medium from LOXL2 siRNA-treated CAFs. LOXL2 expression in stromal cells may be a useful prognostic factor for patients with gastric cancer. Fibroblast-derived LOXL2 may stimulate the motility of gastric cancer cells.


World Journal of Gastroenterology | 2015

Prognostic significance of the lymphocyte-to-monocyte ratio in patients with metastatic colorectal cancer

Masatsune Shibutani; Kiyoshi Maeda; Hisashi Nagahara; Hiroshi Ohtani; Katsunobu Sakurai; Sadaaki Yamazoe; Kenjiro Kimura; Takahiro Toyokawa; Ryosuke Amano; Hiroaki Tanaka; Kazuya Muguruma; Kosei Hirakawa

AIM To evaluate the prognostic significance of the lymphocyte to monocyte ratio (LMR) in patients with unresectable metastatic colorectal cancer who received palliative chemotherapy. METHODS A total of 104 patients with unresectable metastatic colorectal cancer who underwent palliative chemotherapy were enrolled. The LMR was calculated from blood samples by dividing the absolute lymphocyte count by the absolute monocyte count. Pre-treatment LMR values were measured within one week before the initiation of chemotherapy, while post-treatment LMR values were measured eight weeks after the initiation of chemotherapy. RESULTS The median pre-treatment LMR was 4.16 (range: 0.58-14.06). We set 3.38 as the cut-off level based on the receiver operating characteristic curve. Based on the cut-off level of 3.38, 66 patients were classified into the high pre-treatment LMR group and 38 patients were classified into the low pre-treatment LMR group. The low pre-treatment LMR group had a significantly worse overall survival rate (P = 0.0011). Moreover, patients who demonstrated low pre-treatment LMR and normalization after treatment exhibited a better overall survival rate than the patients with low pre-treatment and post-treatment LMR values. CONCLUSION The lymphocyte to monocyte ratio is a useful prognostic marker in patients with unresectable metastatic colorectal cancer who receive palliative chemotherapy.


Journal of Medical Case Reports | 2012

Gastric malignant schwannoma presenting with upper gastrointestinal bleeding: a case report

Masashi Takemura; Kayo Yoshida; Mamiko Takii; Katsunobu Sakurai; Akishige Kanazawa

IntroductionWe report a case of gastric malignant schwannoma presenting with gastrointestinal bleeding.Case presentationA 70-year-old Japanese man presented with gastrointestinal bleeding to our hospital. Gastrointestinal endoscopy revealed a protruding lesion in the gastric body. Hematoxylin and eosin staining of biopsy specimens from this lesion revealed sheets of spindle cells. Immunohistochemistry revealed that these cells were positive for S-100 protein and negative for c-Kit and smooth muscle actin. Because mitosis was diffusely visible, this tumor was diagnosed as a gastric malignant schwannoma. Distal gastrectomy with lymph node dissection was performed and the patients postoperative course was uneventful. However, five months after the surgery, he died from multiple liver metastases.ConclusionCases of gastric malignant schwannoma have rarely been reported. The efficacy of surgical resection and postoperative prognosis continues to remain unclear and should be investigated further.


Journal of Surgical Oncology | 2015

The outcome of surgical treatment for elderly patients with gastric carcinoma

Katsunobu Sakurai; Kazuya Muguruma; Hisashi Nagahara; Kenjiro Kimura; Takahiro Toyokawa; Ryosuke Amano; Naoshi Kubo; Hiroaki Tanaka; Hiroshi Ohtani; Masakazu Yashiro; Kiyoshi Maeda; Masaichi Ohira; Kosei Hirakawa

The aim of this study was to clarify the operative mortality and long‐term survival of gastrectomy for elderly patients with gastric cancer.


Gastric Cancer | 2016

Lysyl oxidase is associated with the epithelial-mesenchymal transition of gastric cancer cells in hypoxia.

Hiroaki Kasashima; Masakazu Yashiro; Haruhito Kinoshita; Tatsunari Fukuoka; Tamami Morisaki; Go Masuda; Katsunobu Sakurai; Naoshi Kubo; Masaichi Ohira; Kosei Hirakawa

PurposeIt has been reported that lysyl oxidase (LOX) is a hypoxia-responsive factor and is associated with the malignant progression of carcinoma. The aim of this study was to clarify the relationship between the epithelial–mesenchymal transition (EMT) and LOX in gastric cancer cells under hypoxia.MethodsTwo gastric cancer cell lines, OCUM-2MD3 and OCUM-12, were used in an in vitro study. The effect of LOX small interfering RNA (siRNA) on the EMT and motility of gastric cancer cells under hypoxic condition was analyzed by reverse transcription PCR, Western blot, a wound-healing assay, and an invasion assay. Correlations between LOX expression and the clinicopathological features of 544 patients with gastric carcinoma were examined immunohistochemically.ResultsHypoxic conditions increased the number of polygonal or spindle-shaped cells resulting from EMT in gastric cancer cells. The EMT of cancer cells induced by hypoxia was inhibited by treatment with LOX siRNA. The number of migrating and invading gastric cancer cells in hypoxia was significantly decreased by LOX knockdown. LOX siRNA significantly increased the E-cadherin level and decreased the vimentin level of gastric cancer cells. LOX expression was significantly associated with invasion depth, tumor differentiation, lymph node metastasis, lymphatic invasion, venous invasion, and peritoneal metastasis. Multivariable analysis revealed that LOX was an independent parameter for overall survival.ConclusionLOX affects the EMT of gastric cancer cells in hypoxic conditions. LOX expression is a useful prognostic factor for patients with gastric cancer.


Journal of Cardiothoracic Surgery | 2012

Metachronous pulmonary metastasis after radical esophagectomy for esophageal cancer: prognosis and outcome

Masashi Takemura; Katsunobu Sakurai; Mamiko Takii; Kayo Yoshida

BackgroundFew reports discuss the outcome of pulmonary metastasis after radical esophagectomy for esophageal cancer. To clarify the data from such cases, we conducted a retrospective study on the clinical outcome of patients who developed pulmonary metastasis after undergoing radical esophagectomy.MethodsWe retrospectively reviewed the prognosis and clinical outcome of 25 patients who developed metachronous pulmonary metastasis after esophagectomy for esophageal cancer.ResultsThe site of recurrence was pulmonary without extrapulmonary metastasis in 14 patients and extrapulmonary metastasis was observed in 11. Nineteen patients had multiple pulmonary metastasis and 6 had solitary pulmonary metastasis. Twenty-four of patients underwent systemic chemotherapy during initial treatment for metastatic lesions. Pulmonary metastasectomy was indicated in 5 patients with solitary metastasis. The actual 1-, 2- and 4-year survival rates were 60%, 36% and 27%, respectively. Gender, operative procedure, and postoperative morbidity were not significant prognostic factors. However, pathological staging of primary esophageal cancer was a significant prognostic factor. Survival was significantly worse in patients who did not undergo resection than in those who did. The number of pulmonary metastasis, complicated extrapulmonary metastasis and the time of recurrence were also significant prognostic factors.ConclusionsMultiple pulmonary metastases or complicated extrapulmonary metastasis were unfavorable prognostic factors for patients with pulmonary metastasis arising from esophageal cancer. Although, surgical intervention is not recommended in such cases, metastasectomy is an acceptable choice of treatment for solitary pulmonary metastasis.


PLOS ONE | 2014

Comparative Proteomics Analysis of Gastric Cancer Stem Cells

Tamami Morisaki; Masakazu Yashiro; Anna Kakehashi; Azusa Inagaki; Haruhito Kinoshita; Tatsunari Fukuoka; Hiroaki Kasashima; Go Masuda; Katsunobu Sakurai; Naoshi Kubo; Kazuya Muguruma; Masaichi Ohira; Hideki Wanibuchi; Kosei Hirakawa

Cancer stem cells (CSCs) are responsible for cancer progression, metastasis, and recurrence. To date, the specific markers of CSCs remain undiscovered. The aim of this study was to identify novel biomarkers of gastric CSCs for clinical diagnosis using proteomics technology. CSC-like SP cells, OCUM-12/SP cells, OCUM-2MD3/SP cells, and their parent OCUM-12 cells and OCUM-2MD3 cells were used in this study. Protein lysates from each cell line were analyzed using QSTAR Elite Liquid Chromatography with Tandem Mass Spectrometry, coupled with isobaric tags for relative and absolute quantitation technology. Candidate proteins detected by proteomics technology were validated by immunohistochemical analysis of 300 gastric cancers. Based on the results of LC-MS/MS, eight proteins, including RBBP6, GLG1, VPS13A, DCTPP1, HSPA9, HSPA4, ALDOA, and KRT18, were up-regulated in both OCUM-12/SP cells and OCUM-2MD3/SP cells when compared to their corresponding parent cells. RT-PCR analysis indicated that the expression level of RBBP6, HSPA4, DCTPP1, HSPA9, VPS13A, ALDOA, GLG1, and CK18 was high in OCUM-12/SP and OCUM-2MD3/SP, in compared with the control of parent OCUM-12 and OCUM-2MD3. These proteins were significantly associated with advanced invasion depth, lymph node metastasis, distant metastasis, or advanced clinical stage. RBBP6, DCTPP1, HSPA4, and ALDOA expression in particular were significantly associated with a poor prognosis in the 300 gastric cancer patients. RBBP6 was determined to be an independent prognostic factor. The motility-stimulating ability of OCUM-12/SP cells and OCUM-2MD3/SP cells was inhibited by RBBP6 siRNA. These findings might suggest that the eight proteins, RBBP6, GLG1, VPS13A, DCTPP1, HSPA9, HSPA4, ALDOA, and KRT18, utilizing comparative proteomics analysis, were perceived to be potential CSC markers of gastric cancer. Of the eight candidate proteins, RBBP6 was suggested to be a promising prognostic biomarker and a therapeutic target for gastric cancer.

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