Tsutomu Hamasaki
Nippon Medical School
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Featured researches published by Tsutomu Hamasaki.
Urological Research | 1998
Tsutomu Hamasaki; Tomotaka Hattori; Go Kimura; Nando Nakazawa
Abstract Tumor cells at the stage of tumor progression build up a high tolerance to intrinsic and extrinsic defence systems and/or therapeutic procedures, and the cells deeply infiltrate the adjacent tissue, which is followed by tumor metastasis to remote organs and tissues. This study was designed to investigate the relationship between expression of matrix metalloproteinase-2 (MMP-2) and invasiveness of human bladder cancer cells, using cell lines derived from a parental human urinary bladder tumor cell line, T24. Two subpopulations of the human bladder cancer cell line T24, Hi-T24 and Lo-T24, were selected using an invasion assay and then expression of MMP-2 mRNA and protein was analyzed by reverse-transcription polymerase chain reaction (RT-PCR) and enzyme immunoassay (EIA). The gross morphology, cell growth rate, and adhesion activity to a basement membrane extract (matrigel) of the high-invasive Hi-T24 cells were similar to those of the low-invasive Lo-T24 cells, but the Hi-T24 cells were 3.8-fold more haptotactic through matrigel than the Lo-T24 cells. The haptotactic activity of the Hi-T24 cells was suppressed by the addition of an anti-MMP-2 antibody, and the amounts of MMP-2 protein secreted into the spent medium by the Hi-T24 and Lo-T24 cells were 7.8 ± 0.2 and 3.8 ± 0.3 ng/ml (P < 0.05), respectively. The quantities of tissue inhibitor of metalloproteinase-2 (TIMP-2) protein secreted by Hi-T24 and Lo-T24 cells were 133.2 ± 4.3 and 168.7 ± 5.6 ng/ml, respectively (P < 0.05). The levels of transcription of the genes encoding MMP-2 and the transmembrane MMP, MT-MMP, evaluated by RT-PCR, were higher in the Hi-T24 cells than in the Lo-T24 cells. Expression of the TIMP-2 gene was slightly lower in the Hi-T24 cells than in the Lo-T24 cells. These results indicate that expression of the metalloproteinases are imbalanced at the gene level in human urinary bladder cancer cells at the stage of tumor progression.
BMC Urology | 2013
Shunichiro Nomura; Yasutomo Suzuki; Ryo Takahashi; Mika Terasaki; Ryoji Kimata; Tsutomu Hamasaki; Go Kimura; Akira Shimizu; Yukihiro Kondo
BackgroundNeoadjuvant chemotherapy has been shown to have benefit in T1 high-grade or T2 bladder cancer. However, neoadjuvant chemotherapy fails in some patients. Careful patient selection for neoadjuvant chemotherapy is therefore needed. Several reports show that Snail is associated with resistance to chemotherapy. We hypothesized that Snail expression could predict survival in T1 high-grade and T2 bladder cancer patients treated with neoadjuvant chemotherapy.MethodsThe participants were 44 patients with T1 high-grade and T2 bladder cancer receiving neoadjuvant chemotherapy. Immunohistochemical analysis was used to determine Snail expression in specimens of bladder cancer obtained by transurethral resection before neoadjuvant chemotherapy. The relationships between Snail expression and patients’ outcomes were analyzed.ResultsSnail expression was positive in 15 of the 44 patients (34.1%) and negative in 29 (65.9%). Disease-free survival was significantly shorter for the Snail-positive group than for the Snail-negative group (p = 0.014). In addition, disease-specific survival was also significantly shorter for the Snail-positive group than for the Snail-negative group (p = 0.039). In multivariate analysis, Snail expression level was identified as an independent prognostic factor for disease-specific survival (p = 0.020).ConclusionsThe results indicate that Snail expression may predict poor outcome in T1 high-grade and T2 bladder cancer patients treated with neoadjuvant chemotherapy.
Geriatrics & Gerontology International | 2015
Ryoji Kimata; Kaoru Nemoto; Yuji Tomita; Ryo Takahashi; Tsutomu Hamasaki; Yukihiro Kondo
To investigate whether the insertion of a thermoexpandable metallic prostate stent (Memokath) facilitates the removal of Foley catheters in elderly patients ineligible for urethral obstruction surgery because of the potential complications involved in long‐term catheter management.
International Journal of Urology | 2005
Yukihiro Kondo; Ichiro Matsuzawa; Jun Watanabe; Tsutomu Hamasaki; Kazuhiro Yoshida; Taiji Nishimura
Purpose: Vesicourethral anastomosis in laparoscopic prostatectomy is a very difficult procedure. Our purpose in this study was to evaluate a new method using extracorporeal bladder neck traction with nylon thread for vesicourethral anastomosis during laparoscopic radical prostatectomy.
Journal of Endourology | 2015
Kenji Yoshida; Akira Yokomizo; Tadashi Matsuda; Tsutomu Hamasaki; Yukihiro Kondo; Kunihisa Yamaguchi; Hiro-omi Kanayama; Yoshiaki Wakumoto; Shigeo Horie; Seiji Naito
PURPOSE To assess whether our ureteroscopic real-time navigation system has the possibility to reduce radiation exposure and improve performance of ureteroscopic maneuvers in surgeons of various ages and experience levels. MATERIALS AND METHODS Our novel ureteroscopic navigation system used a magnetic tracking device to detect the position of the ureteroscope and display it on a three-dimensional image. We recruited 31 urologists from five institutions to perform two tasks. Task 1 consisted of finding three internal markings on the phantom calices. Task 2 consisted of identifying all calices by ureteroscopy. In both tasks, participants performed with simulated fluoroscopy first, followed by our navigation system. Accuracy rates (AR) for identification, required time (T) for completing the task, migration length (ML), and time exposed to simulated fluoroscopy were recorded. RESULTS The AR, T, and ML for both tasks were significantly better with the navigation system than without it (Task 1 with simulated fluoroscopy vs with navigation: AR 87.1 % vs 98.9%, P=0.003; T 355 s vs 191 s, P<0.0001; ML 4627 mm vs 2701 mm, P<0.0001. Task 2: AR 88.2% vs 96.7%, P=0.011; T 394 s vs 333 s, P=0.027; ML 5966 mm vs 5299 mm, P=0.0006). In both tasks, the participants used the simulated fluoroscopy about 20% of the total task time. CONCLUSIONS Our navigation system, while still under development, could help surgeons of all levels to achieve better performances for ureteroscopic maneuvers compared with using fluoroscopic guidance. It also has the potential to reduce radiation exposure during fluoroscopy.
International Journal of Urology | 2001
Shuichi Osawa; Taiji Nishimura; Masataka Akimoto; Hiroyuki Abe; Tsutomu Hamasaki; Shuichi Kuroda
Abstract The successful repair of a fistula between the bladder and the perineal skin using a femoral gracilis flap is reported. A 70‐year‐old woman, who 10 years previously had undergone a total hysterectomy for uterine cancer, developed a fistula between the bladder and the perineal skin after she underwent Miles operation for rectal cancer. Initially, an attempt was made to repair the fistula by the transabdominal approach. This failed, probably because of the lack of supporting tissue between the bladder and the perineal skin. The second repair was performed with plastic surgeons. A secure three‐layer bladder closure was accomplished. A right femoral gracilis flap was developed and rotated 180° to fill the defect in the skin and subcutaneous tissue. Four weeks after surgery, cystography revealed no fistula or urinary leakage and the drainage catheter was removed. Femoral gracilis flap interposition was successful for repair of a fistula between the bladder and the perineal skin when there was no supporting tissue due to extensive exenteration in the surgical removal of rectal cancer and after other repair procedures had been unsuccessful.
Urologia Internationalis | 1999
Hiroyuki Abe; Taiji Nishimura; Shuichi Osawa; Tsutomu Hamasaki; Takafumi Miura; Kazunori Ikeda; Fumiatu Oka; Yoshiharu Ohaki
A method of multiple random biopsy combined with bladder wall aspiration and snare in bladder cancer is presented. Our method was used on 23 patients with clinically superficial bladder cancer and was found to have advantages in obtaining an adequate amount of tissue with minimal thermal degeneration.
International Braz J Urol | 2014
Jun Akatsuka; Yasutomo Suzuki; Tsutomu Hamasaki; Go Kimura; Yukihiro Kondo
Neither computed tomography (CT) nor intravenous pyelography (IVP) alone can diagnose tumors of renal pelvic diverticula, but magnetic resonance urography (MRU) can obtain accurate preoperative information.
The Japanese Journal of Urology | 2017
Ryo Amakawa; Jun Akatsuka; Yasutomo Suzuki; Tsutomu Hamasaki; Go Kimura; Hideaki Ishii; Yukihiro Kondo
IgG4-related kidney disease (IgG4-RKD) is a comprehensive term for renal lesions associated with IgG4-related disease (IgG4-RD), which is a recently recognized clinical entity characterized by a dense lymphoplasmacytic infiltrate rich in IgG4+ plasma cells with fibrosis affecting several organs. A 70-year-old woman was referred to our hospital for an abnormality at the left renal hilum detected by CT scan. Urinalysis was negative, urine cytology was rated as Class IIIa, and contrast-enhanced CT revealed left renal pelvic wall thickening without an irregular lumen and swelling of bilateral obturator lymph nodes. Ureterorenoscopy and biopsy were performed, and results showed no evidence of malignancy. Then, laparoscopic pelvic lymphadenectomy was performed. Plasma cells were the predominant infiltrating inflammatory cells; immunostaining showed marked infiltration of IgG4+ plasma cells with >10 IgG4+ plasma cells per high-power field, and the IgG4+/IgG+ cell ratio was over 40%. Serum IgG4 was extremely high. We made a final diagnosis of possible IgG4-related disease according to Comprehensive diagnostic Criteria for IgG4-related disease 2011. We report a long-term (40-month) follow-up case of IgG4-related kidney disease without therapy because there are no symptoms.
The Journal of Urology | 2014
Shunichiro Nomura; Yasutomo Suzuki; Jun Akatsuka; Ryo Takahashi; Mika Terasaki; Ryoji Kimata; Ichiro Matsuzawa; Tsutomu Hamasaki; Go Kimura; Akira Shimizu; Yukihiro Kondo
(Pinteraction 1⁄4 0.609). Among individuals with GSTM1 null and present genotypes, the corresponding ORs were 2.91 (95% CI, 0.44-19.09) and 4.21 (95% CI, 1.26-14.14), respectively (Pinteraction 1⁄4 0.712). CONCLUSIONS: Our findings support the hypothesis that genetic factors play a role in bladder cancer etiology. Whether these correspond to low-penetrance cancer-predisposing polymorphisms acting together and/or interacting with environmental factors warrants further research.