Hiroaki Yasumoto

Prediction of survival benefit using an automated bone scan index in patients with castration-resistant prostate cancer.

Study Type – Prognosis (case series)

Identification of lymphatic pathway involved in the spreading of prostate cancer by fluorescence navigation approach with intraoperatively injected indocyanine green

OBJECTIVE : The objective of this study was to identify lymphatic vessels draining from the prostate by using a fluorescence navigation (FN) system. METHODS : Fourteen subjects were candidates for radical retropubic prostatectomy (RRP) and pelvic lymph node dissection (PLND). After an indocyanine green solution was injected into the prostate during RRP, lymphatic vessels draining from the prostate were analyzed using a FN system. After PLND based on lymphatic mapping by the FN system (in vivo probing) was performed in the external iliac, obturator and internal iliac regions; the fluorescence of the removed lymph nodes (LNs) was analyzed on the bench (ex vivo probing). RESULTS : Under in vivo and ex vivo probing, the fluorescence intensity of internal iliac nodes was greater than that of external iliac or obturator nodes. CONCLUSION : The current study suggests that using a FN system after injecting indocyanine green is a safe and rational approach for detecting the lymphatic channel draining from the prostate. The major lymphatic pathway involved in the spreading of prostate cancer appears to relate to internal iliac LNs, which would mean that the standard PLND covering external iliac and obturator regions would not keep the cancer from spreading.

Topographic anatomy of the male perineal structures with special reference to perineal approaches for radical prostatectomy

Aim: Although perineal approaches for radical prostatectomy have recently gained renewed attention as excellent methods for minimally invasive surgery, the most commonly used techniques, Belts and Youngs approaches, have inadequacies regarding the topographical relationship between the rectourethral and levator ani muscles.

Lower urinary tract symptoms and risk of prostate cancer in Japanese men

Aim: Our aim was to investigate whether or not men with lower urinary tract symptoms are at increased risk of prostate cancer.

Impact of radical perineal prostatectomy on urinary continence and quality of life: A longitudinal study of Japanese patients

Aim: We used self‐completed questionnaires to obtain a longitudinal assessment of urinary continence and urinary, bowel, and sexual domain‐related quality of life (QOL) in Japanese patients undergoing radical perineal prostatectomy (RPP).

Fate of residual fragments after successful extracorporeal shock wave lithotripsy

Purpose: The aim of the present study was to investigate the reason residual fragments from upper urinary tract calculi failed to clear after successful extracorporeal shock wave lithotripsy (ESWL).

Indocyanine green (ICG)-based fluorescence navigation system for discrimination of kidney cancer from normal parenchyma: application during partial nephrectomy

PurposeTo determine the definite border between normal and tumor kidney tissues during partial nephrectomy (PN) procedures using intraoperative indocyanine green (ICG)-based fluorescence imaging.MethodsSixteen potential candidates for PN with organ-confined, small renal masses treated between July 2008 and June 2011 at Shimane University Hospital were enrolled. An ICG-based fluorescence navigation (FN) system was used to evaluate the border between the tumor and normal kidney parenchyma (step 1), the cavity following tumor excision (step 2), and the negative surgical margin of resected tissues (step 3). The R.E.N.A.L nephrometry score (RNS) was applied to evaluate the correlation between tumor anatomy and ICG-based fluorescence imaging.ResultsIn step 1, in vivo probing revealed 14 tumors with a mean RNS of 7 points that showed quite low ICG fluorescence signals in the tumor mass as compared with normal kidney parenchyma. In step 2, in vivo probing around the bed revealed highly fluorescent signals with no remnant tumor residing in 10 cases with a mean RNS of 6 points. In step 3, ex vivo probing revealed cancer tissues involving normal parenchyma that were completely excised with minimum amounts of normal parenchyma in all 16 resected specimens.ConclusionsICG-based FN system was very helpful for confirming negative margin status in even the most complex cases. Further evaluations may open the door for widespread use of this ICG-based FN system as a feasible and attractive alternative during a PN procedure.

Current chemotherapeutic strategies against bladder cancer

Urothelial cancer is a chemotherapy-sensitive malignancy, with the regimen of methotrexate, vinblastine, doxorubicin, and cisplatin (M-VAC) until recently considered to be the first choice for chemotherapy. Poor survival and substantial toxicity associated with M-VAC have led to investigations into alternative chemotherapy strategies, and the combination of gemcitabine and cisplatin (GC) may be promising. In addition, combination chemotherapy of taxanes along with gemcitabine and/or platinum-based agents is also considered to provide clinical benefits as second-line chemotherapy following M-VAC or GC therapy. In the near future, results of trials using molecular target therapies may bring improved outcomes for patients with bladder cancer.

CYP1B1 promotes tumorigenesis via altered expression of CDC20 and DAPK1 genes in renal cell carcinoma

BackgroundCytochrome P450 1B1 (CYP1B1) has been shown to be up-regulated in many types of cancer including renal cell carcinoma (RCC). Several reports have shown that CYP1B1 can influence the regulation of tumor development; however, its role in RCC has not been well investigated. The aim of the present study was to determine the functional effects of CYP1B1 gene on tumorigenesis in RCC.MethodsExpression of CYP1B1 was determined in RCC cell lines, and tissue microarrays of 96 RCC and 25 normal tissues. To determine the biological significance of CYP1B1 in RCC progression, we silenced the gene in Caki-1 and 769-P cells by RNA interference and performed various functional analyses.ResultsFirst, we confirmed that CYP1B1 protein expression was significantly higher in RCC cell lines compared to normal kidney tissue. This trend was also observed in RCC samples (p < 0.01). Interestingly, CYP1B1 expression was associated with tumor grade and stage. Next, we silenced the gene in Caki-1 and 769-P cells by RNA interference and performed various functional analyses to determine the biological significance of CYP1B1 in RCC progression. Inhibition of CYP1B1 expression resulted in decreased cell proliferation, migration and invasion of RCC cells. In addition, reduction of CYP1B1 induced cellular apoptosis in Caki-1. We also found that these anti-tumor effects on RCC cells caused by CYP1B1 depletion may be due to alteration of CDC20 and DAPK1 expression based on gene microarray and confirmed by real-time PCR. Interestingly, CYP1B1 expression was associated with CDC20 and DAPK1 expression in clinical samples.ConclusionsCYP1B1 may promote RCC development by inducing CDC20 expression and inhibiting apoptosis through the down-regulation of DAPK1. Our results demonstrate that CYP1B1 can be a potential tumor biomarker and a target for anticancer therapy in RCC.

Tumor Suppressor Function of PGP9.5 Is Associated with Epigenetic Regulation in Prostate Cancer—Novel Predictor of Biochemical Recurrence after Radical Surgery

Background: The expression level of protein G product 9.5 (PGP9.5) is downregulated because of promoter CpG hypermethylation in several tumors. We speculated that impaired regulation of PGP9.5 through epigenetic pathways is associated with the pathogenesis of prostate cancer. Methods: CpG methylation of the PGP9.5 gene was analyzed in cultured prostate cancer cell lines, 226 localized prostate cancer samples from radical prostatectomy cases, and 80 benign prostate hyperplasia (BPH) tissues. Results: Following 5-aza-2′-deoxycytidune treatment, increased PGP9.5 mRNA transcript expression was found in the LNCaP and PC3 cell lines. With bisulfite DNA sequencing, partial methylation of the PGP9.5 promoter was shown in LNCaP whereas complete methylation was found in PC3 cells. After transfection of PGP9.5 siRNA, cell viability was significantly accelerated in LNCaP but not in PC3 cells as compared with control siRNA transfection. Promoter methylation of PGP9.5 was extremely low in only one of 80 BPH tissues, whereas it was found in 37 of 226 prostate cancer tissues. Expression of the mRNA transcript of PGP9.5 was significantly lower in methylation (+) than methylation (−) prostate cancer tissues. Multivariate analysis of biochemical recurrence (BCR) after an radical prostatectomy revealed pT category and PGP9.5 methylation as prognostically relevant. Further stratification with the pT category in addition to methylation status identified a stepwise reduction of BCR-free probability. Conclusion: This is the first clinical and comprehensive study of inactivation of the PGP9.5 gene via epigenetic pathways in primary prostate cancer. Impact: CpG methylation of PGP9.5 in primary prostate cancer might become useful as a molecular marker for early clinical prediction of BCR after radical prostatectomy. Cancer Epidemiol Biomarkers Prev; 21(3); 487–96. ©2012 AACR.