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Dive into the research topics where Suguru Shirotake is active.

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Featured researches published by Suguru Shirotake.


Clinical Cancer Research | 2010

Expression of Snail in Upper Urinary Tract Urothelial Carcinoma: Prognostic Significance and Implications for Tumor Invasion

Takeo Kosaka; Eiji Kikuchi; Shuji Mikami; Akira Miyajima; Suguru Shirotake; Masaru Ishida; Yasunori Okada; Mototsugu Oya

Purpose: There are few molecular markers known to predict upper urinary tract urothelial carcinomas (UTUC) prognosis. Snail, which contributes to epithelial–mesenchymal transition (EMT), has been documented in cancer progression, but not clear yet in UTUC. We therefore addressed the expression and biological significance of Snail in UTUC. Experimental Design: To elucidate the biological significance of Snail in UTUC, we examined the immunohistochemical expression of snail in UTUC and analyzed its clinical significance in 150 patients with UTUC. Biological effects of Snail in EMT and invasion were evaluated by using small interfering RNA (siRNA) specific for Snail in urothelial carcinoma cell lines and the Matrigel invasion assay. Results: Nuclear Snail staining was very weak in superficial UTUC. In contrast, strong Snail staining was observed in many of the nucleus of invasive UTUC. Snail expression was significantly higher in the high tumor stage, high grade, and in tumors showing lymphovascular invasion (LVI). Multivariate Cox regression analysis revealed that elevated Snail expression was a significant and an independent prognostic predictor of recurrence-free survival and cancer-specific survival. Patients with positive LVI and high Snail expression showed the worse outcome. Targeting of Snail mRNA expression in UMUC-3 cells with Snail-specific siRNA downregulated the mRNA expression of Snail, Vimentin, MMP2, and MMP9. Furthermore, the cells with siRNA for Snail showed decreased invasion activity in comparison with the cells transfected with a nontargeting siRNA. Conclusion: Snail-induced EMT represents a clinically relevant mechanism of UTUC progression and an attractive target for the treatment of patients with UTUC. Clin Cancer Res; 16(23); 5814–23. ©2010 AACR.


European Urology | 2014

The Predictive Value of C-reactive Protein for Prognosis in Patients with Upper Tract Urothelial Carcinoma Treated with Radical Nephroureterectomy: A Multi-institutional Study

Nobuyuki Tanaka; Eiji Kikuchi; Suguru Shirotake; Kent Kanao; Kazuhiro Matsumoto; Hiroaki Kobayashi; Yasumasa Miyazaki; Hiroki Ide; Jun Obata; Katsura Hoshino; Nozomi Hayakawa; Yujiro Ito; Takeo Kosaka; Kiichiro Kodaira; Masafumi Oyama; Akira Miyajima; Tetsuo Momma; Ken Nakagawa; Munehisa Ueno; Mototsugu Oya

BACKGROUND Few studies have discussed the prognostic impact of serum C-reactive protein (CRP) level in upper tract urothelial carcinoma (UTUC). OBJECTIVE To investigate whether the perioperative level of CRP provides additional prognostic information following radical nephroureterectomy (RNU). DESIGN, SETTING, AND PARTICIPANTS A total of 564 patients with UTUC from a retrospective multi-institutional cohort were included. The median follow-up was 32 mo. INTERVENTION All patients underwent RNU without neoadjuvant chemotherapy, while 106 patients (18.8%) received adjuvant chemotherapy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Associations between perioperative CRP level and outcome were assessed using multivariate analysis. A serum CRP level >0.50mg/dl was defined as elevated. RESULTS AND LIMITATIONS Preoperative CRP (pre-CRP) level was elevated in 136 patients (24.1%). Multivariate analysis showed that pre-CRP elevation was an independent predictor of subsequent disease recurrence (hazard ratio [HR]: 1.47 for CRP 0.51-2.00; HR: 1.89 for CRP >2.00). Five-year recurrence-free survival rates were 69.2% in patients with pre-CRP levels ≤ 0.50 mg/dl, 54.3% in patients with pre-CRP levels between 0.51 and 2.00 mg/dl, and 35.4% in patients with pre-CRP levels >2.00 mg/dl (p<0.001). Similar results were found in cancer-specific mortality, showing that pre-CRP elevation was an independent predictor of worse outcome (HR: 1.74 for CRP 0.51-2.00; HR: 2.31 for CRP >2.00). In a subgroup analysis of the elevated pre-CRP group, postoperative normalisation of CRP level was an independent predictor of better outcome. This study is limited by its retrospective nature as well as its heterogeneous group of patients and variable follow-up protocols resulting from the multi-institution design. CONCLUSIONS Serum CRP may become a possible biomarker in UTUC, suggesting that patients with an elevated pre-CRP level could be predicted to have subsequent disease recurrence and cancer-specific mortality, while postoperative normalisation of CRP level was an independent predictor for prognosis.


The Prostate | 2009

Ets‐1 and hypoxia inducible factor‐1α inhibition by angiotensin II type‐1 receptor blockade in hormone‐refractory prostate cancer

Takeo Kosaka; Akira Miyajima; Suguru Shirotake; Eiji Kikuchi; Masanori Hasegawa; Shuji Mikami; Mototsugu Oya

Accumulating evidences have suggested that the renin‐angiotensin system (RAS) participates in the regulation of tumor angiogenesis. We previously demonstrated that hormone‐refractory prostate cancer (HRPC) showed significantly higher angiotensin II (Ang II) type‐1 receptor (AT1R) expression, and that the AT1R blocker (ARB) exerted protective effects by inhibiting angiogenesis. However, the downstream transcriptional factors induced by Ang II in prostate cancer cells have not been fully elucidated yet.


The Journal of Urology | 2011

Long-Term Androgen Ablation and Docetaxel Up-Regulate Phosphorylated Akt in Castration Resistant Prostate Cancer

Takeo Kosaka; Akira Miyajima; Suguru Shirotake; Eriko Suzuki; Eiji Kikuchi; Mototsugu Oya

PURPOSE There are still few effective therapeutic options for advanced prostate cancer. One of the most troublesome aspects of prostate cancer is that androgen dependent prostate cancer inevitably progresses to highly aggressive, life threatening castration resistant prostate cancer after androgen ablation therapy. To our knowledge it remains unknown how sensitivity to docetaxel changes during progression to more aggressive castration resistant prostate cancer under androgen ablation. MATERIALS AND METHODS We investigated sensitivity to docetaxel and phosphorylated Akt status in C4-2 and C4-2AT6 cells established at our institution. RESULTS C4-2AT6 cells established under androgen ablation conditions for 6 months showed significantly higher resistance to docetaxel than C4-2 cells in vivo and in vitro. Resistance was accompanied by increased phosphorylated Akt. In C4-2AT6 cells phosphorylated Akt activity was significantly up-regulated by docetaxel in a dose dependent manner. After treatment with docetaxel and a phosphatidylinositol 3-kinase/Akt inhibitor the sensitivity of C4-2AT6 cells to docetaxel markedly increased through enhanced apoptotic death. CONCLUSIONS Findings indicated that up-regulation of phosphorylated Akt during androgen ablation and its further activation by docetaxel explains at least in part the resistance to docetaxel and progression to castration resistant prostate cancer under androgen ablation conditions.


Urology | 2011

Angiotensin II Type 1 Receptor Expression and Microvessel Density in Human Bladder Cancer

Suguru Shirotake; Akira Miyajima; Takeo Kosaka; Nobuyuki Tanaka; Takahiro Maeda; Eiji Kikuchi; Mototsugu Oya

OBJECTIVES To determine whether angiotensin II type 1 receptor (AT1R) expression and tumor angiogenesis in human bladder cancer (BCa) specimens acquired by transurethral resection (TUR). It has recently been reported that AT1R is expressed in several tumors and is involved in tumor angiogenesis. However, no study has investigated AT1R expression in association with angiogenesis in clinical specimens of bladder cancer. METHODS Surgical specimens were obtained from 108 patients who had undergone TUR for bladder cancer. All specimens were pathologically diagnosed as urothelial carcinoma. AT1R expression and microvessel density (MVD) were determined by immunostaining. The clinical and pathologic characteristics were retrospectively reviewed. RESULTS The MVD was greater in muscle-invasive BCa (MIBC; 29 cases, 34.4 ± 4.1/0.25 mm(2)) than in non-MIBC (NMIBC; 79 cases, 17.4 ± 1.1/0.25 mm(2), P < .0001). AT1R expression was greater in the MIBC (P = .0004) and high-grade (P = .0063) specimens than in the NMIBC and low-grade specimens. In addition, the greater expression of AT1R was significantly associated with MVD (P < .05). In NMIBC, the factors significantly affecting recurrence-free survival on univariate analysis were AT1R (P = .02), MVD (P < .0001), tumor multiplicity (P = .0007), and bacille Calmette-Guérin intravesical instillation after TUR (P = .0026). Multivariate analysis revealed that tumor multiplicity and no BCG intravesical instillation after TUR were independent predictors of 5-year recurrence-free survival, and AT1R and MVD were independent predictors of 1-year recurrence-free survival (P < .01). CONCLUSIONS AT1R expression and MVD were related to early intravesical recurrence in NMIBC. The results suggest that AT1R could become a new molecular target and a prognostic factor for NMIBC.


American Journal of Pathology | 2012

Regulation of Monocyte Chemoattractant Protein-1 Through Angiotensin II Type 1 Receptor in Prostate Cancer

Suguru Shirotake; Akira Miyajima; Takeo Kosaka; Nobuyuki Tanaka; Eiji Kikuchi; Shuji Mikami; Yasunori Okada; Mototsugu Oya

Monocyte chemoattractant protein-1 (MCP-1/CCL2) is reported to contribute to tumor progression and is regulated by the renin-angiotensin system in hypertensive disease. In this study, we investigated the clinical outcome of MCP-1 expression in patients with prostate cancer (CaP) and the regulation of MCP-1 through angiotensin II (AngII) type 1 receptor (AT1R) in CaP. Specimens were obtained from 138 CaP patients and analyzed by immunostaining for both MCP-1 and macrophages. We investigated the regulation of MCP-1 expression through AT1R both in vivo and in vitro using three human prostate cancer cell lines: LNCaP, C4-2, and C4-2AT6. Specimens with a high Gleason score (≥7) and a high pathological classification (≤pT3), and those with castration-resistant prostate cancer showed significantly higher MCP-1 expression and higher macrophage infiltration than low malignant potential CaP. High MCP-1 expression in CaP correlated significantly with high prostate-specific antigen (PSA) recurrence rates. AngII induced significantly higher MCP-1 levels in C4-2AT6 than in LNCaP, whereas AT1R blockade (ARB) inhibited MCP-1 production via the inhibition of the PI3K/Akt pathway in C4-2AT6. ARB also significantly suppressed MCP-1 expression in C4-2AT6 tumors. Our study is the first to demonstrate that both high MCP-1 expression and high macrophage infiltration in CaP specimens correlate with a high PSA recurrence rate and that ARB inhibits MCP-1 expression through the PI3K/Akt pathway and blocks macrophage infiltration in castration-resistant prostate cancer.


BJUI | 2013

Patient characteristics and outcomes in metastatic upper tract urothelial carcinoma after radical nephroureterectomy: the experience of Japanese multi‐institutions

Nobuyuki Tanaka; Eiji Kikuchi; Kent Kanao; Kazuhiro Matsumoto; Hiroaki Kobayashi; Yasumasa Miyazaki; Hiroki Ide; Jun Obata; Katsura Hoshino; Suguru Shirotake; Nozomi Hayakawa; Takeo Kosaka; Akira Miyajima; Tetsuo Momma; Ken Nakagawa; Shintaro Hasegawa; Yosuke Nakajima; Mototsugu Oya

To investigate oncological outcomes and prognostic factors in patients with upper tract urothelial carcinoma (UTUC) who experienced disease recurrence after radical nephroureterectomy (RNU). Few studies have focused on the clinical courses of patients who experienced disease recurrence after RNU.


British Journal of Cancer | 2011

Acquired platinum resistance enhances tumour angiogenesis through angiotensin II type 1 receptor in bladder cancer

Nobuyuki Tanaka; Akira Miyajima; Takeo Kosaka; Yasumasa Miyazaki; Suguru Shirotake; H Shirakawa; Eiji Kikuchi; Mototsugu Oya

Background:We investigated the changes in reactive oxygen species (ROS) and angiogenesis through angiotensin II (Ang II) type 1 receptor (AT1R) after the development of acquired platinum resistance in bladder cancer.Methods:Four invasive human bladder cancer cell lines, T24, 5637, T24PR, and 5637PR, were used in vitro, whereas in vivo, T24 and T24PR cells were used. T24PR and 5637PR cells were newly established at our institution as acquired platinum-resistant sublines by culturing in cisplatin (CDDP)-containing conditioned medium for 6 months.Results:Ang II induced significantly higher vascular endothelial growth factor (VEGF) production in T24PR and 5637PR cells than in their corresponding parent cells in vitro, whereas Ang II induced a further increase in VEGF production. These platinum-resistant cells also showed significantly higher AT1R expression than their corresponding parent cells. ROS was also significantly upregulated in T24PR and 5637PR cells, whereas increased AT1R expression was significantly downregulated by scavenging free radicals. We also demonstrated the efficacy of AT1R blockade at suppressing the growth of platinum-resistant xenograft model.Conclusion:Our findings indicate a new molecular mechanism for upregulated AT1R signalling through increased ROS when tumours progressed after the CDDP-based regimens, and shed light on the importance of AT1R blockade for platinum-resistant bladder cancers.


Molecular Cancer Therapeutics | 2010

Cis-dichlorodiammineplatinum Upregulates Angiotensin II Type 1 Receptors through Reactive Oxygen Species Generation and Enhances VEGF Production in Bladder Cancer

Nobuyuki Tanaka; Akira Miyajima; Takeo Kosaka; Suguru Shirotake; Masanori Hasegawa; Eiji Kikuchi; Mototsugu Oya

We previously reported that angiotensin II type 1 receptor (AT1R) antagonists enhanced the cytotoxity of cis-dichlorodiammineplatinum (CDDP) in a bladder cancer xenograft model. To elucidate the synergistic mechanism, we investigated whether reactive oxygen species (ROS) generation induced by CDDP may affect the regulation of AT1R expression. Five invasive human bladder cancer cell lines, T24, UMUC-3, 5637, KU-1, and KU-19-19, were used in the in vitro study. For the in vivo study, T24 cells were used. We also examined AT1R and vascular endothelial growth factor (VEGF) expression in human bladder cancer specimens that had been treated with CDDP-based chemotherapy. The in vitro study showed that AT1R expression was significantly upregulated by CDDP in T24, KU-1, and KU-19-19 cells. On the other hand, AT1R expression was not changed in UMUC-3 and 5637 cells. ROS generation was also significantly upregulated by CDDP in T24, KU-1, and KU-19-19 cells. The upregulation of AT1R expression induced by CDDP was significantly suppressed by scavenging free radicals. Angiotensin II induced VEGF production in CDDP-treated cells; however, the AT1R antagonist significantly inhibited the increase in VEGF. The in vivo study results also showed that CDDP treatment upregulated AT1R expression, resulting in increased VEGF. Clinical specimens from patients who underwent cystectomy after neoadjuvant CDDP-based chemotherapy showed significantly higher AT1R and VEGF expression than corresponding transurethral resection specimens. Our findings indicate that CDDP upregulates AT1R expression though ROS generation and enhances VEGF production. Therefore, AT1R blockade may be an effective strategy for bladder cancer in combination with CDDP-based chemotherapy. Mol Cancer Ther; 9(11); 2982–92. ©2010 AACR.


The Journal of Urology | 2015

Impact of an Adjuvant Chemotherapeutic Regimen on the Clinical Outcome in High Risk Patients with Upper Tract Urothelial Carcinoma: A Japanese Multi-Institution Experience

Suguru Shirotake; Eiji Kikuchi; Nobuyuki Tanaka; Kazuhiro Matsumoto; Yasumasa Miyazaki; Hiroaki Kobayashi; Hiroki Ide; Jun Obata; Katsura Hoshino; Gou Kaneko; Masayuki Hagiwara; Takeo Kosaka; Kent Kanao; Kiichiro Kodaira; Satoshi Hara; Masafumi Oyama; Tetsuo Momma; Akira Miyajima; Ken Nakagawa; Shintaro Hasegawa; Yosuke Nakajima; Mototsugu Oya

PURPOSE Current guidelines do not yet provide any recommendations for adjuvant chemotherapy in patients with upper tract urothelial carcinoma managed with radical nephroureterectomy. We evaluated whether an adjuvant chemotherapeutic regimen would affect the clinical outcome in patients with high risk upper tract urothelial carcinoma. MATERIALS AND METHODS We identified 873 patients who had undergone radical nephrouretectomy for localized upper tract urothelial carcinoma at 14 Japanese institutions between 1993 and 2011. We assessed whether the type of regimen, such as methotrexate, vinblastine, doxorubicin and cisplatin, and gemcitabine and cisplatin, in an adjuvant setting, could affect the subsequent clinical outcome of patients with upper tract urothelial carcinoma. RESULTS On multivariate analysis pathological T stage, tumor grade, lymphovascular invasion and lymph node involvement were prognostic factors for recurrence-free survival and cancer specific survival. We defined 229 patients with 3 or more of these factors as the high risk group. In an analysis according to adjuvant regimen, Kaplan-Meier curves showed that the 1 and 2-year recurrence-free survival rates in the methotrexate, vinblastine, doxorubicin and cisplatin treated group were 71.4% and 47.9%, which were significantly higher than in the gemcitabine and cisplatin treated group (48.2% and not reached, p=0.022) or those not treated with adjuvant chemotherapy (53.4% and 39.6%, p=0.039). Similar results were observed in terms of cancer specific survival. CONCLUSIONS Our study showed that pT3-4, tumor grade 3, positive lymphovascular invasion and lymph node involvement were independent risk factors for disease mortality in patients with upper tract urothelial carcinoma treated with radical nephroureterectomy. In the high risk group methotrexate, vinblastine, doxorubicin and cisplatin adjuvant chemotherapy contributed to improve subsequent mortality compared to gemcitabine and cisplatin or no adjuvant chemotherapy.

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Masafumi Oyama

Saitama Medical University

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Kent Kanao

Aichi Medical University

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