Koichiro Minami

Adipose-derived stromal cells inhibit prostate cancer cell proliferation inducing apoptosis.

Mesenchymal stem cells (MSCs) have generated a great deal of interest in the field of regenerative medicine. Adipose-derived stromal cells (AdSCs) are known to exhibit extensive proliferation potential and can undergo multilineage differentiation, sharing similar characteristics to bone marrow-derived MSCs. However, as the effect of AdSCs on tumor growth has not been studied sufficiently, we assessed the degree to which AdSCs affect the proliferation of prostate cancer (PCa) cell. Human AdSCs exerted an inhibitory effect on the proliferation of androgen-responsive (LNCaP) and androgen-nonresponsive (PC3) human PCa cells, while normal human dermal fibroblasts (NHDFs) did not, and in fact promoted PCa cell proliferation to a degree. Moreover, AdSCs induced apoptosis of LNCaP cells and PC3 cells, activating the caspase3/7 signaling pathway. cDNA microarray analysis suggested that AdSC-induced apoptosis in both LNCaP and PC3 cells was related to the TGF-β signaling pathway. Consistent with our in vitro observations, local transplantation of AdSCs delayed the growth of tumors derived from both LNCaP- and PC3-xenografts in immunodeficient mice. This is the first preclinical study to have directly demonstrated that AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway, irrespective of androgen-responsiveness. Since autologous AdSCs can be easily isolated from adipose tissue without any ethical concerns, we suggest that therapy with these cells could be a novel approach for patients with PCa.

Incidence of urethral stricture after bipolar transurethral resection of the prostate using TURis: results from a randomised trial

To assess whether bipolar transurethral resection of the prostate (B‐TURP) using the TURis® system has a similar level of efficacy and safety to that of the traditional monopolar transurethral resection of the prostate (M‐TURP), and to evaluate the impact of the TURis system on postoperative urethral stricture rates over a 36‐month follow‐up period.

MiR-145 negatively regulates Warburg effect by silencing KLF4 and PTBP1 in bladder cancer cells

The Warburg effect is a well-known feature in cancer-specific metabolism. We previously reported on the role of microRNA (miR)-145 as a tumor-suppressor in human bladder cancer (BC) cells. In this study, we reveal that miR-145 decreases the Warburg effect by silencing KLF4 in BC cells. The expression levels of miR-145 were significantly lower in clinical BC samples and BC cell lines compared to those in normal tissues and HUC cells. Luciferase assay results showed that miR-145 directly bound to 3′UTR of KLF4, which was shown to be overexpressed in the clinical BC samples using Western blot analysis and immunohistochemistry. Remarkable growth inhibition and apoptosis were induced by the ectopic expression of miR-145 or by the gene silencing of KLF4 (siR-KLF4). Also, Warburg effect-related genes such as PTBP1/PKMs were regulated by the transfection of BC cells with miR-145 or siR-KLF4. These results thus indicate that the miR-145/KLF4/PTBP1/PKMs axis is one of the critical pathways that maintain the Warburg effect in BC carcinogenesis. MiR-145 perturbed the Warburg effect by suppressing the KLF4/PTBP1/PKMs pathway in BC cells, resulting in significant cell growth inhibition.

A Novel Combination RNAi toward Warburg Effect by Replacement with miR-145 and Silencing of PTBP1 Induces Apoptotic Cell Death in Bladder Cancer Cells

Bladder cancer is one of the most difficult malignancies to control. We explored the use of a novel RNA-interference method for a driver oncogene regulating cancer specific energy metabolism by the combination treatment with a small interfering RNA (siRNA) and a microRNA. After transfection of T24 and 253JB-V cells with miR-145 and/or siR-PTBP1, we examined the effects of cell growth and gene expression by performing the trypan blue dye exclusion test, Western blot, Hoechst 33342 staining, reverse transcription polymerase chain reaction (RT-PCR), and electron microscopy. The anti-cancer effects of xenograft model mice with miR-145 and/or siR-PTBP1 were then assessed. The combination treatment induced the deeper and longer growth inhibition and reduced the levels of both mRNA and protein expression of c-Myc and polypyrimidine tract-binding protein 1 (PTBP1) more than each single treatment. Notably, the combination treatment not only impaired the cancer specific energy metabolism by inhibiting c-Myc/PTBP1/PKMs axis but also inactivated MAPK/ERK and PI3K/AKT pathways examined in vitro and in vivo. Furthermore, the combination treatment induced apoptosis or autophagy; but, in some cells, apoptotic cell death was accompanied by autophagy, because the condensation of chromatin and many autophagosomes were coexistent. This combination treatment could be a novel RNA-interference strategy through the systemic silencing of the Warburg effect-promoting driver oncogene PTBP1 in bladder cancer cells.

Novel Bladder Preservation Therapy with Osaka Medical College Regimen

PURPOSE We investigated the effect of balloon occluded arterial infusion of an anticancer agent (cisplatin/gemcitabine), used concomitantly with hemodialysis, which delivers an extremely high concentration of anticancer agent to the tumor site without systemic adverse effects, along with concurrent radiation (referred to as the Osaka Medical College regimen) in patients with advanced bladder cancer. MATERIALS AND METHODS A total of 329 patients (TisN0 16, T2N0 174, T3N0 77, T4N0 22 and TxN+ 40) were assigned to receive the Osaka Medical College regimen. Patients who did not achieve complete response underwent total cystectomy or secondary balloon occluded arterial infusion with an increased amount of cisplatin and/or gemcitabine. RESULTS The Osaka Medical College regimen allowed 83.6% (276 of 329) of patients in total and 93.6% (250 of 267) of patients with organ confined disease (including T3b) to achieve complete response. Of the patients with a complete response 96% (240 of 250) survived with a functional bladder without evidence of recurrent disease within a mean followup of 159 weeks. Although lymph node involvement, especially N2 stage, was selected as a significant risk factor for treatment failure and survival, it was noteworthy that 61.9% of patients with N1 disease achieved complete response and that the 5-year overall survival rate was 72.2%. No patients had grade III or more severe toxicities. CONCLUSIONS The Osaka Medical College regimen, a new bladder preservation strategy, can be curative not only in patients for whom cystectomy is indicated, but also in patients whose condition is not amenable to curative treatment because of disease stage, age or other factors, and for whom merely palliative therapy would otherwise seem the only option.

Effect of a novel bladder preservation therapy, BOAI-CDDP-radiation (OMC-regimen)

We have developed a novel form of bladder preservation therapy [OMC (Osaka Medical College)-regimen] involving balloon-occluded-arterial-infusion (BOAI) of an anticancer agent (cisplatin/gemcitabine), used concomitantly with hemodialysis, which delivers an extremely high concentration of anticancer agent to the site of a tumor without systemic adverse effects, along with concurrent radiation. We previously reported that the OMC-regimen elicited a complete response (CR) in >90% of patients with organ confined tumors, while LN(+), T4 tumors and a non-UC histological type were statistically significant risk factors for treatment failure and patient survival. In this study, we investigated the effects of the OMC-regimen in patients with organ confined urothelial cancer tumors and the outcomes were compared to those with total cystectomy. Three hundred and one patients were assigned to receive either the OMC-regimen (n=162) or total cystectomy (n=139). Patients in the OMC-regimen group who failed to achieve CR underwent cystectomy, or secondary BOAI with an increased amount of CDDP or gemcitabine (1600 mg). The OMC-regimen yielded 98.1% of clinical response; CR in 93.8% (152/162) of patients; PR in 4.3% (7/162). More than 96% of the CR patients (146/152) were alive with no evidence of recurrence after a mean follow-up of 166 (range 23-960) weeks. No patients suffered grade III toxicity; all patients successfully completed this therapy. The patient survival was significantly better compared to the cystectomy group; the overall 5-, 10- and 15-year survival rates were 87.3, 79.6 and 59.7%, respectively. Moreover, the 5-, 10- and 15-year bladder intact survival rates, the most important issue for bladder preservation therapy, were 85.7, 78.4 and 58.8%, respectively. In conclusion, the OMC-regimen is a useful bladder-preservation strategy, not only in those for whom cystectomy is indicated, but also in patients whose condition is not amenable to curative treatment and for whom palliation would otherwise seem the only option.

The systemic inflammation-based Glasgow Prognostic Score as a powerful prognostic factor in patients with upper tract urothelial carcinoma

Introduction and Objective The combination of C-reactive protein and albumin, the Glasgow Prognostic Score (GPS), had independent prognostic value in patients with varying cancers, except for upper tract urothelial carcinoma (UTUC). The aim of this study was to describe the relationship between GPS and survival in patients with UTUC after adjustment for other prognostic factors. Materials and Methods We queried 2 UTUC databases. Retrospective clinical series on patients with localized UTUC managed by nephroureterectomy with bladder cuff, for whom data from the Yamaguchi Uro-Oncology Group and Osaka Medical College registry, including age, presence of bladder cancer, pT stage, lymphovascular invasion, C-reactive protein (CRP) and albumin, were analyzed. The GPS was constructed by combining CRP and albumin. Cancer specific survival (CSS) and overall survival (OS) and relative excess risk of death were estimated by GPS categories after adjusting for gender, age, ECOG performance status (PS), grade, and lymphovascular invasion (LVI). Results Seven hundred and twenty four UTUC patients were identified. Our final cohort included 574 patients; of these, 29.2% died during a maximum follow up of 16.7 years. The estimated mean 10-year CSS of patients with GPS of scre-0, -1, and -2 was 99.5, 95.1, and 75.9 months, respectively. Patients with GPS of score-2 had poorest 10-year estimated mean OS of 67.6 months (57.2–77.9). Raised GPS also had a significant association with excess risk of cancer death at 10 years (GPS 2: Relative Excess Risk = 1.74, 95% CI 1.20–2.54) after adjusting for gender, patients’ age, ECOG PS, and tumor focality. C-index of GPS both for CSS and OS were superior to patients’ age and tumor focality, and comparable to grade. Conclusions The GPS is an independent prognostic factor for CSS and OS after surgery with curative intent for localized UTUC. It significantly increases the accuracy of established prognostic factors. The GPS may provide a meaningful adjunct for patient counseling and clinical trial design.

The Anti-Proliferative Effect of Boron Neutron Capture Therapy in a Prostate Cancer Xenograft Model

Purpose Boron neutron capture therapy (BNCT) is a selective radiation treatment for tumors that preferentially accumulate drugs carrying the stable boron isotope, 10B. BNCT has been evaluated clinically as an alternative to conventional radiation therapy for the treatment of brain tumors, and more recently, recurrent advanced head and neck cancer. Here we investigated the effect of BNCT on prostate cancer (PCa) using an in vivo mouse xenograft model that we have developed. Materials and Methods Mice bearing the xenotransplanted androgen-independent human PCa cell line, PC3, were divided into four groups: Group 1: untreated controls; Group 2: Boronophenylalanine (BPA); Group 3: neutron; Group 4: BPA-mediated BNCT. We compared xenograft growth among these groups, and the body weight and any motility disturbance were recorded. Immunohistochemical (IHC) studies of the proliferation marker, Ki-67, and TUNEL staining were performed 9 weeks after treatment. Results The in vivo studies demonstrated that BPA-mediated BNCT significantly delayed tumor growth in comparison with the other groups, without any severe adverse events. There was a significant difference in the rate of freedom from gait abnormalities between the BPA-mediated BNCT group and the other groups. The IHC studies revealed that BNCT treatment significantly reduced the number of Ki-67-positive cells in comparison with the controls (mean±SD 6.9±1.5 vs 12.7±4.0, p<0.05), while there was no difference in the number of apoptotic cells, suggesting that BPA-mediated BNCT reduced PCa progression without affecting apoptosis at 9 weeks post-treatment. Conclusions This study has provided the first preclinical proof-of-principle data to indicate that BPA-mediated BNCT reduces the in vivo growth of PCa. Although further studies will be necessary, BNCT might be a novel potential treatment for PCa.

Feasibility of Photodynamic Diagnosis for Challenging TUR- Bt Cases Including Muscle Invasive Bladder Cancer, BCG Failure or 2 nd -TUR

BACKGROUND Despite widely adopted standard methods for follow-up including cystoscopy plus cytology, recurrence rates of non muscle-invasive bladder cancer (NMIBC) have not improved over the past decades, still ranging from 60% through 70%. Hence, widely acceptable surveillance strategies with excellent sensitivity are needed. Early recurrence has led to the development of a novel cystoscopy technique utilizing photodynamic diagnosis (PDD). Although, no studies have evaluated the efficacy of PDD for patients of MIBC, BCG failure or 2nd-transurethelial resection (TUR). MATERIALS AND METHODS The present study was performed from October 2012 through May 2013. IRB approved 25 patients initially underwent a cystoscopy examination of white light and blue light followed by the resection of tumors identified. Resections were performed from bladder mucosa areas considered suspicious at PDD, along with PDD negative normal bladder mucosa area resected by random biopsy. Specimens were divided into two groups, PDD positive and negative. Primary endpoints were sensitivity and specificity. RESULTS A total of 147 specimens extracted from 25 patients were included in the analysis. Some 45 out of 92 PDD-positive specimens were confirmed to have bladder cancer, and 51 out of PDD-negative 55 specimens were confirmed to be cancer negative. The sensitivity of PDD was 91.8% (45/49) and specificity was 52.0% (51/98). The sensitivity:specificity was 89.5% (17/19) : 47.6% (30/63) in 12 2nd-TUR patients, 90.5% (19/21) : 61.1% (11/18) in seven MIBC patients, and 95.0% (19/20) : 48.5% (16/33) in eight failed BCG cases. CONCLUSIONS PDD-TURBT has high sensitivity to diagnose BC even for 2nd-TUR, MIBC or BCG failure cases.

E74-like factor inhibition induces reacquisition of hormone sensitiveness decreasing period circadian protein homolog 1 expression in prostate cancer cells ☆

Purpose Initiating as an androgen-dependent adenocarcinoma, prostate cancer (PCa) gradually progresses to a castrate-resistant disease following androgen deprivation therapy with a propensity to metastasize. Methods In order to resolve the mechanism of castrate-resistant PCa, we performed a cDNA-microarray assay of two PCa cell lines, LNCaP (androgen dependent) and C4-2 (androgen independent). Among them, we focused on a novel Ets transcription factor, E74-like factor 5 (ELF5), the expression level of which was extremely high in C4-2 in comparison with LNCaP both in the microarray analysis and real-time polymerase chain reaction analysis, and investigated the biological role in acquisition of androgen-refractory PCa growth. Results Western blot analysis and morphological analysis using confocal immunofluorescence microscopy demonstrated that ELF5 was expressed mainly in cytosol both in LNCaP and C4-2. Inhibition of ELF5 expression using ELF5-small interfering RNA in C4-2 induced decreased expression of androgen receptor corepressor, period circadian protein homolog 1, and MTT assay of C4-2 after ELF5 small interfering RNA transfection showed the same cell growth pattern of LNCaP. Conclusions Our in vitro experiments of cell growth and microarray analysis have demonstrated for the first time that decreased expression of period circadian protein homolog 1 due to ELF5 inhibition may induce the possibility of reacquisition of hormone sensitiveness of PCa cells. We suggest that ELF5 could be a novel potential target for the treatment of hormone-refractory PCa patients.