Yoshiaki Wakumoto

Progress reports on immune gene therapy for stage IV renal cell cancer using lethally irradiated granulocyte-macrophage colony-stimulating factor-transduced autologous renal cancer cells

Abstract There is no effective treatment for patients with stage IV renal cell cancer (RCC), although the introduction of new therapy is imminent. Cancer gene therapy is currently considered to be one of the most promising therapeutic modalities in the field of cancer treatment. Based on the results of animal studies, vaccination using autologous granulocyte-macrophage colony-stimulating factor-transduced renal cancer cells appears promising. Before initiating a clinical study using an ex vivo gene-transduced autologous cell vaccine-based immunogene therapy for RCC in Japan, in 1992 we initially planned a Japanese version of a clinical protocol in collaboration with a US group. In 1993, the original protocol was refined. We performed five preclinical qualification studies using RCC nephrectomy specimens from patients in 1997, and the results showed that preparation of RCC cells for autologous vaccines at the Clinical Cell Technology Facility, Research Hospital of the Institute of Medical Science, University of Tokyo, was feasible. Subsequently in August 1998, the Ministry of Health and Welfare and the Ministry of Education, Science, Culture, and Sport approved our clinical protocol. We have recruited two patients with stage IV RCC to our study so far. Here we report the background to the initiation of cancer gene therapy in Japan.

Testosterone replacement alters the cell size in visceral fat but not in subcutaneous fat in hypogonadal aged male rats as a late-onset hypogonadism animal model

Background Patients with late-onset hypogonadism (LOH) benefit from testosterone replacement by improvement in the parameters of the metabolic syndrome, but fat cell morphology in these patients is still unclear. This study aims to determine the effect of testosterone replacement on the morphology of fat cells in subcutaneous and visceral adipose tissue and on erectile function in hypogonadal aged male rats as a model of LOH. Methods Ten male Sprague-Dawley rats aged 20–22 months were randomly allocated to two groups, ie, aged male controls (control group, n=5) and aged males treated with testosterone replacement therapy (TRT group, n=5). Testosterone enanthate 25 mg was injected subcutaneously every 2 weeks for 6 weeks. At 6 weeks, the intracavernous pressure (ICP) and mean arterial blood pressure (MAP) ratio was assessed. Visceral and subcutaneous adipose tissue specimens were collected and analyzed using Image-J software. Results Body weight at 2, 4, and 6 weeks after TRT was 800.0±35.4 g, 767.5±46.3 g, and 780±40.4 g, respectively (not statistically significant). The ICP/MAP ratio was 0.341±0.015 in the TRT group and 0.274±0.049 in the control group (not statistically significant). The median subcutaneous fat cell size was 4.85×103 (range 0.85–12.53×103) μm2 in the control group and 4.93×103 (range 6.42–19.7×103) μm2 in the TRT group (not statistically significant). In contrast, median visceral fat cell size was significantly smaller in the TRT group (4.93×103 μm2 [range 0.51–14.88×103]) than in the control group (6.08×103 μm2 [0.77–19.97×103]; P<0.001, Mann-Whitney U test). Conclusion This is the first study clearly indicating that TRT can decrease visceral fat cell size, which is a key modulator in the metabolic syndrome. However, a short course of TRT could not improve the ICP response in hypogonadal aged male rats. Further investigation is necessary to clarify the exact rationale of TRT on the visceral fat cell.

CA19-9 as a Serum Marker for Poor Prognosis in Urothelial Carcinoma

Introduction: To evaluate the role of serum carbohydrate antigen 19-9 (CA19-9) in the prognosis and follow-up evaluation of patients with urothelial carcinoma, the authors studied the association of the serum level and positive rate with clinical features such as infiltration and metastasis in 164 patients admitted to the authors’ department. Patients and Methods: This study included 164 cases of patients with urohelial carcinoma. The absolute value of the serum CA19-9 level and its positive rate were tested. Simple variant analysis and logistic regression analysis were used for estimation of statistical significance. Kaplan-Meier’s test and Cox’s proportional hazard model were used for analysis of survival. Results: Significant differences in the serum CA19-9 levels were found with regard to the following parameters: the presence or absence of metastasis, clinical stage, depth of invasion, and degree of differentiation. The positive rate displayed a significant difference only for the presence or absence of metastasis. With regard to the presence of metastasis, serum CA19-9 was a significant risk factor along with depth of invasion in logistic regression analysis. Comparison of the survival rate indicated the prognosis to be significantly poor in the positive group and serum CA19-9 was regarded to be a prognostic risk factor in analysis via the regression model. Conclusions: Serum CA19-9 is thought to serve as a significant marker for advanced cancer and tumors with highly malignant potential and is useful for predicting prognosis of the disease.

Clinical efficacy and prognostic factors of tumor progression in Japanese patients with advanced renal cell carcinoma treated with sorafenib

OBJECTIVE Result of clinical trial for registration purpose is often difficult to generalize because of its limited population in number and inclusion criteria. METHODS To understand the efficacy of sorafenib under daily medical practice, we retrospectively investigated therapeutic outcomes of 175 Japanese patients with advanced renal cell carcinoma treated with sorafenib at 15 centers. RESULTS The objective response rate and disease control rate were 15.4 and 77.1%, respectively, being similar to those in the Phase II study in Japanese patients (19.4 and 73.6 months). Any tumor shrinkage was observed with 53% of patients, while tumor control without growth was in 61%. Lung lesions were more sensitive to sorafenib than other lesions, in terms of any tumor shrinkage (54%) and the extent of maximal shrinkage, while tumor control was better in lymph node metastases (77%) than in lung (69%). Liver was worse in any tumor shrinkage (35%), tumor control (55%) and the extent of tumor growth. Slightly, shorter median overall survival of 21.1 months compared with Phase II clinical trial (25.3 months) is likely to be attributable to different patient population, because median overall survival was improved to 26.4 months when the population was matched to that in Phase II trial. Univariate and multivariate analyses identified prognostic factors for worse overall survival, including intermediate and poor Memorial Sloan-Kettering Cancer Center risk, Eastern Cooperative Oncology Group performance status ≥1, the presence of non-clear cell component and the presence of liver metastasis. CONCLUSIONS In conclusion, the present study confirmed the efficacy of sorafenib in the real-world setting on advanced renal cell carcinoma.

Focal partial salvage low-dose-rate brachytherapy for local recurrent prostate cancer after permanent prostate brachytherapy with a review of the literature

Purpose To investigate the treatment results for focal partial salvage re-implantation against local recurrence after permanent prostate brachytherapy. Material and methods Between January 2010 and September 2015, 12 patients were treated with focal partial salvage re-implantation for local recurrence after low-dose-rate brachytherapy using 125I seeds. The focal clinical target volume (F-CTV) was delineated on positive biopsy areas in a mapping biopsy, combining the cold spots on the post-implant dosimetry for initial brachytherapy. The F-CTV was expanded by 3 mm to create the planning target volume (PTV) as a margin to compensate for uncertainties in image registration and treatment delivery. The prescribed dose to the PTV was 145 Gy. The characteristics and biochemical disease-free survival (BdFS) rates were analyzed. Genitourinary (GU) and gastrointestinal (GI) toxicities were evaluated using the Common Terminology Criteria for Adverse Events version 4. Results The median prostate-specific antigen (PSA) level at re-implantation was 4.09 ng/ml (range: 2.91-8.24 ng/ml). The median follow-up time was 56 months (range: 6-74 months). The median RD2cc and UD10 were 63 Gy and 159 Gy, respectively. The 4-year BdFS rate was 78%, which included non-responders. Biochemical recurrence occurred in two patients after 7 and 31 months, respectively. The former was treated with hormonal therapy after biochemical failure, and the latter underwent watchful waiting (PSA at the last follow-up of 53 months: 7.3 ng/ml) at the patients request. No patients had grade 3 GU/GI toxicities or died after salvage re-implantation. Conclusions The partial salvage low-dose-rate brachytherapy used to treat local recurrence after permanent prostate brachytherapy is well-tolerated, with high biochemical response rates. This treatment can be not only a method to delay chemical castration but also a curative treatment option in cases of local recurrence of prostate carcinoma after seed implantation.

Development and Validation of a Novel Recurrence Risk Stratification for Initial Non-muscle Invasive Bladder Cancer in Asia.

Background Some risk classifications to determine prognosis of patients with non-muscle invasive bladder cancer (NMIBC) have disadvantages in the clinical setting. We investigated whether the EORTC (European Organization for Research and Treatment of Cancer) risk stratification is useful to predict recurrence and progression in Japanese patients with NMIBC. In addition, we developed and validated a novel, and simple risk classification of recurrence. Methods The analysis was based on 1085 patients with NMIBC at six hospitals. Excluding recurrent cases, we included 856 patients with initial NMIBC for the analysis. The Kaplan–Meier method with the log-rank test were used to calculate recurrence-free survival (RFS) rate and progression-free survival (PFS) rate according to the EORTC risk classifications. We developed a novel risk classification system for recurrence in NMIBC patients using the independent recurrence prognostic factors based on Cox proportional hazards regression analysis. External validation was done on an external data set of 641 patients from Kyorin University Hospital. Findings There were no significant differences in RFS and PFS rates between the groups according to EORTC risk classification. We constructed a novel risk model predicting recurrence that classified patients into three groups using four independent prognostic factors to predict tumour recurrence based on Cox proportional hazards regression analysis. According to the novel recurrence risk classification, there was a significant difference in 5-year RFS rate between the low (68.4%), intermediate (45.8%) and high (33.7%) risk groups (P < 0.001). Interpretation As the EORTC risk group stratification may not be applicable to Asian patients with NMIBC, our novel classification model can be a simple and useful prognostic tool to stratify recurrence risk in patients with NMIBC. Funding None.

The Advantage of a Ureteroscopic Navigation System with Magnetic Tracking in Comparison with Simulated Fluoroscopy in a Phantom Study

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.

Hypoxia-Inducible Protein 2 (HIG2), a Novel Diagnostic Marker for Renal Cell Carcinoma and Potential Target for Molecular Therapy

To identify molecules to serve as diagnostic markers for renal cell carcinoma (RCC) and as targets for novel therapeutic drugs, we investigated genome-wide expression profiles of RCCs using a cDNA microarray. We subsequently confirmed that hypoxia-inducible protein-2 (HIG2) was expressed exclusively in RCCs and fetal kidney. Induction of HIG2 cDNA into COS7 cells led to secretion of the gene product into culture medium and resulted in enhancement of cell growth. Small interfering RNA effectively inhibited expression of HIG2 in human RCC cells that endogenously expressed high levels of the protein and significantly suppressed cell growth. Moreover, addition of polyclonal anti-HIG2 antibody into culture medium induced apoptosis in RCC-derived cell lines. By binding to an extracellular domain of frizzled homologue 10 (FZD10), HIG2 protein enhanced oncogenic Wnt signaling and its own transcription, suggesting that this product is likely to function as an autocrine growth factor. ELISA analysis of clinical samples identified secretion of HIG2 protein into the plasma of RCC patients even at an early stage of tumor development, whereas it was detected at significantly lower levels in healthy volunteers or patients with chronic glomerulonephritis. The combined evidence suggests that this molecule represents a promising candidate for development of molecular-targeting therapy and could serve as a prominent diagnostic tumor marker for patients with renal carcinomas.

Papillary Renal Cell Carcinoma

Papillary renal cell carcinoma is an uncommon variant of renal cell carcinoma which has unique features including hypovascularity or avascularity, extensive stromal macrophage infiltration and better prognosis than that for nonpapillary renal cell carcinoma. Two cases of papillary renal cell carcinoma presenting hypovascular or avascular angiology are presented. Histologically, the two tumors had a purely papillary structure. Papillae were lined by a layer of epithelial cells which lacked prominent cellular atypia, and there were numerous macrophages in the stroma. In addition, in one patient, extensive calcification of the tumor capsule was present. Furthermore, our experience in the present study with imprint cytology indicates that it offers corroborative information for the intraoperative diagnosis made on the basis of frozen section examination. Acta Pathol Jpn 42: 298 303, 1992.

Circulating tumor cell count during zoledronic acid treatment in men with metastatic prostate cancer: a pilot study

Purpose Recent clinical trials have demonstrated that zoledronic acid (ZOL) significantly prolongs survival in prostate cancer patients undergoing androgen deprivation therapy. This pilot study investigated the influence of ZOL on circulating tumor cell (CTC) counts in prostate cancer patients in association with prostate-specific antigen (PSA) used as a serum biomarker. Methods Patients with metastatic castration-resistant prostate cancer (CRPC) who were CTC-positive (n=4) were enrolled in treatment with ZOL between April 2012 and December 2013. CTCs were detected using the Cell Search System. The study evaluated CTC fluctuations at 1, 2, and 3 months versus baseline, as well as patient outcomes and adverse events. Results Two patients showed evidence of temporally decreased CTCs after ZOL treatment. Instead of decreasing the number of CTCs, the PSA level did not go down during the ZOL treatment. One patient could not undergo ZOL treatment due to rapid disease progression. Conclusions Although CTC count arguably provides useful information about patients undergoing ZOL treatment, the positive influence of ZOL may be limited to temporary effects for CRPC.