[A Case of Metastatic Prostate Cancer with Neuroendocrine Differentiation with Long-Term Survival after Multidisciplinary Therapy].

A 74-year-old man visited the urology clinic with the chief complaint of urinary retention in December 2014. Serum level of initial prostate specific antigen (PSA) was 50 ng/ml and he was diagnosed with Gleason Score 4＋4 prostate adenocarcinoma with regional lymphadenopathy (cT3aN1M0). PSA level had declined after the treatment with combined androgen blockade. In November 2018, he was diagnosed with castration resistant prostate cancer (CRPC) as local progression was detected by computed tomography (CT) while PSA level did not increase. Since local symptoms worsened, resulting in repeated hematuria after the treatment with enzalutamide, palliative radiation therapy to the prostate (45 Gy) was performed. Five months later, follow-up CT showed multiple metastasis in bilateral lung and left testicle. Serum level of neuron-specific enolase (NSE) was 24.4 ng/ml without an elevated in serum PSA level. He received rebiopsy of the prostate, but no malignant findings were observed. Consequently, bilateral orchiectomy was performed for diagnosis of left testicular tumor. Pathological examination revealed metastasis of neuroendocrine prostate cancer (NEPC). Chemotherapy using cisplatin and irinotecan was administered after orchiectomy. Complete response of lung lesions was achieved and serum level of NSE decreased within normal range. No recurrence has been confirmed for 4 years after the completion of chemotherapy.

Comparison of Oncological Outcomes between Transperitoneal and Retroperitoneal Approaches in Laparoscopic Nephroureterectomies for Upper Tract Urothelial Carcinoma.

Background and Objectives: Our aim was to clarify the oncological outcomes of the two different approaches to laparoscopic nephroureterectomies (LNUs) in Japan, and to examine whether there were any significant differences between the transperitoneal approach and the retroperitoneal approach. Materials and Methods: We retrospectively evaluated patients who underwent an LNU for upper tract urothelial carcinoma (UTUC) from January 2013 to December 2022. We identified 52 patients who underwent a transperitoneal LNU (tLNU) and 93 who underwent a retroperitoneal LNU (rLNU). We adopted age, smoking, and pT-stage matching, and 43 patients were classified in each group. We investigated the time from surgery to recurrence (RFS: recurrence-free survival), the time to death (OS: overall survival), and the time to non-urothelial-tract recurrence-free survival (NUTRFS). A Cox regression analysis was performed to evaluate the risk factors that influenced recurrence. Results: There were no significant differences in the RFS, OS, and NUTRFS between the two matched groups. In the multivariate Cox regression analysis, the pT stage (pT3≥ vs. pT2≤) had an HR = 2.09 and a p = 0.01, and was an independent prognostic risk factor regarding cancer recurrence. Conclusions: There were no significant differences in the oncological outcomes between the tLNU and rLNU groups. It is suggested that the transperitoneal approach should be selected for LNUs.

Investigation of eligibility for adjuvant therapy from real-world data of patients with urothelial carcinoma undergoing radical cystectomy and radical nephroureterectomy.

OBJECTIVE: Adjuvant nivolumab prolonged disease-free survival compared with placebo in patients at high risk of recurrence following radical cystectomy or radical nephroureterectomy in the CheckMate 274 trial. However, the ideal eligibility criteria for adjuvant therapy in real-world clinical practice remain controversial. METHODS: We retrospectively analyzed clinical data of 409 patients who underwent radical cystectomy (n = 252) or radical nephroureterectomy (n = 157) and validated the risk of recurrence based on the classification used in the CheckMate 274 trial. We also investigated the impact of perioperative chemotherapy, lymph node dissection and pathological factors on prognosis. RESULTS: The median follow-up time was 37.5 and 32.1 months in bladder cancer and upper tract urothelial carcinoma, respectively. Among the high-risk patients based on CheckMate 274 trial, disease-free survival was considerably shorter for bladder cancer and upper tract urothelial carcinoma patients than for low-risk patients (hazard ratios: 4.132 and 7.101, respectively). The prevalence of adjuvant chemotherapy in high-risk patients was low (24 and 38% for bladder cancer and upper tract urothelial carcinoma, respectively). The extent of lymph node dissection in bladder cancer and presence of lymph node dissection in upper tract urothelial carcinoma did not affect prognosis. Cox proportional multivariate analysis revealed CheckMate 274-high-risk as a poor prognostic factor in bladder cancer and upper tract urothelial carcinoma. CONCLUSIONS: This study validated the risk classification for recurrence following radical cystectomy and radical nephroureterectomy using the CheckMate 274 criteria in real-world practice. Further research would help assess the degree of benefit obtained from adjuvant nivolumab.

Trend in overall survival from the start of first-line chemotherapy in patients with metastatic urothelial carcinoma.

New approaches involving immune checkpoint inhibitors and antibody-drug conjugates prolong overall survival in patients with metastatic urothelial carcinoma. However, the access to such systemic therapy in clinical practice is suboptimal, and whether these agents improve overall survival in patients with metastatic urothelial carcinoma over time remains unclear. Hence, we investigated the overall survival trend from the initiation of first-line therapy with these agents to identify changes due to the medication and time of treatment initiation. We retrospectively evaluated 195 patients from a single center. They were treated with chemotherapy, pembrolizumab, or avelumab or enfortumab vedotin. The treatment was categorized into chemotherapy, pembrolizumab or avelumab/enfortumab vedotin period. The new agents prolonged overall survival from the start of first-line therapy. Furthermore, sequential treatment with these agents in real-world clinical practice has been reported to prolong overall survival. These study results will have major implications when a new first-line therapy is approved in the future.

[A Case of Metastatic Urothelial Carcinoma with Pseudoprogression of Liver Metastasis during the Treatment with Pembrolizumab].

A 75-year-old woman with a complaint of gross hematuria was referred to our hospital. The patient was diagnosed as having bladder cancer (cT3bN1M0) and received two cycles of chemotherapy with gemcitabine and cisplatin. Radical cystectomy with pelvic lymph node dissection and bilateral ureterostomy was performed after achieving partial response in a lymph node metastasis following chemotherapy. Based on the pathological diagnosis of high-grade (G3) urothelial carcinoma (ypT3aN2), two more cycles of adjuvant chemotherapy with gemcitabine and cisplatin were administered. Four months after completing adjuvant chemotherapy, pulmonary and hepatic metastases appeared, and treatment with pembrolizumab was initiated. The size of the lung metastasis decreased, while that of the liver metastasis increased 2 months after administering pembrolizumab. However, considering treatment beyond progression using checkpoint inhibitors, pembrolizumab was continued, resulting in marked tumor shrinkage of the liver metastasis. After that, pembrolizumab treatment was temporarily discontinued, and radiation therapy was administered for a new lymph node metastasis at the tracheal bifurcation. Eventually, the lymph node metastasis shrank, and the treatment with pembrolizumab was recommenced for 1 year and the metastases remained shrumken.

A retrospective study on optimal number of cycles of the first-line platinum-based chemotherapy for metastatic urothelial carcinoma.

BACKGROUND: Recently, switch maintenance with avelumab has been approved for the treatment of advanced or metastatic urothelial carcinoma (UC), with no progression after four to six cycles of first-line platinum-based chemotherapy. However, the optimal number of cycles of platinum-based chemotherapy has not been determined. OBJECTIVE: To analyze the clinical characteristics of patients with advanced UC who were treated with platinum-based chemotherapy and investigate the association between the number of cycles of the treatment and the patients' overall survival. METHODS: A total of 124 patients with advanced UC who were treated with first-line platinum-based chemotherapy at Osaka City University Hospital between April 2009 and January 2020 were retrospectively reviewed. RESULTS: Of the 124 patients, clinical information regarding overall survival was available for 115 patients. The median age was 72 years (range, 43-95 years). Only 59 patients (51.3 %) were treated with gemcitabine and cisplatin, and 52 patients (45.2 %) were treated with gemcitabine and carboplatin. The median number of cycles was three (1-8), and the percentage of patients who discontinued chemotherapy due to progressive disease was 80.3%, 64.0%, and 86.4% in those receiving one to three, four, and five or more cycles, respectively. Moreover, no difference in overall survival was observed between patients who received four cycles and those who received five or more cycles at both univariate and multivariate levels. CONCLUSIONS: The present study shows that five or more cycles of first-line platinum-based chemotherapy did not prolong overall survival compared with four cycles, suggesting that four cycles of chemotherapy might be sufficient, considering the new treatment strategy involving switch maintenance with avelumab.

Comparison of post-implant dosimetrics between intraoperatively built custom-linked seeds and loose seeds by sector analysis at 24 hours and 1 month for localized prostate cancer.

PURPOSE: To compare post-implant dosimetrics between intraoperatively built custom-linked (IBCL) seeds and loose seeds (LS) at 24 hours and 1 month by sector analysis, and to evaluate the effect of IBCL seeds with regard to change in dosimetric parameters, in patients with prostate cancer treated with brachytherapy. MATERIAL AND METHODS: Consecutive patients treated for localized prostate cancer who received definitive brachytherapy between March 2013 and October 2017 were retrospectively analyzed. Prostate V100 (PV100), prostate D90 (PD90), prostate V150 (PV150), urethral D30 (UD30), urethral V150 (UV150), and rectal V100 (RV100) were assessed. RESULTS: Thirty-two patients were treated with LS and 32 patients were treated with IBCL seeds. The median follow-up time was 49.9 months in the LS group and 27.1 months in the IBCL group. PV150, UV150, and UD30 at 24 hours and UD30 at 1 month showed significant difference (F-test), and standard deviation (SD) tended to be lower in the IBCL group. Analysis of change in the variables revealed significance for ΔPV100 and ΔPD90 (F-test, p = 0.014 and < 0.001, respectively), and ΔPV150 and ΔUD30 showed marginal significance (p = 0.084 and 0.097, respectively). PV150, UV150, and UD30 at 24 hours and 1 month were significantly lower in the IBCL group, and there was no significant difference in PV100, PD90, and RV100 compared with the LS group (t-test). The homogeneity index (HI) was significantly higher in the IBCL group (p < 0.001). CONCLUSIONS: In this retrospective single institutional study, there was a decrease in the SD of the dosimetric parameters in the IBCL group, and it was statistically significant in change in the variables between 24 hours and 1 month (F-test). The use of IBCL seeds significantly decreased PV150, UV150, and UD30, and significantly improved HI, without lowering PD90 or PD100.

Characteristics of urodynamic study parameters associated with intermediate-term continence after robot-assisted radical prostatectomy in elderly patients.

PURPOSE: To investigate the relationship between urodynamic study (UDS) data and recovery of urinary incontinence (UI) in elderly patients who underwent robot-assisted radical prostatectomy (RARP). MATERIALS AND METHODS: Seventy-five prostate cancer (PCa) patients received UDS before and at 3 months after RARP. They were divided into two groups; a younger group (<70 years old, n = 47) and older group (≥70 years, n = 28), and each was classified according to urinary continence (UC) or UI at 3 months post-RARP. Continence was defined as being pad-free or 1-safety pad usage per day. RESULTS: In the older group, preoperative maximum urethral closure pressure (MUCP) in the UI group was significantly lower than that in the UC group. Detrusor overactivity (DO) rate was significantly higher in the older UI group than in the older UC group at both pre- and 3 months post-RARP. Persistent DO rate pre- and post-RARP was significantly higher in the older group than in the younger group. Regardless of age, postoperative DO was an independent predictor of UI 6 months post-RARP. CONCLUSIONS: In elderly patients, low preoperative MUCP and both pre- and postoperative DO are associated with postoperative UI.

Hyperbaric oxygen significantly improves frequent urination, hyperalgesia, and tissue damage in a mouse long-lasting cystitis model induced by an intravesical instillation of hydrogen peroxide.

AIM: To investigate whether hyperbaric oxygen (HBO) is effective for the pathophysiological findings in an IC/PBS-like mouse model induced by intravesical hydrogen peroxide (H2 O2 ). METHODS: Six-week-old ICR female mice (N = 16) were divided into four experimental groups: (1) sham control with intravesical vehicle instillation twice, and without subsequent treatment (N = 4); (2) H2 O2 instillation twice, followed by HBO (100% O2 , 2 ATA, 30 min per session) (N = 4); (3) H2 O2 instillation twice, followed by dummy hyperbaric treatment (air, 2ATA, 30 min per session) (N = 4); and (4) H2 O2 instillation twice, followed by no treatment (N = 4). Body weight, voiding frequency, tidal voiding volume, and individual bladder pain threshold using the von-Frey test were measured. Whole body uptake of an inflammation-specific fluorescent pan-cathepsin was assessed by an in vivo imaging. Immunohistochemical staining and the mRNA expression of several biomarkers associated with chronic inflammation in resected bladders were evaluated. RESULTS: The HBO-treated group showed significant improvement in voiding frequency, tidal voiding volume, and the individual bladder pain threshold. Moreover, HBO markedly suppressed H2 O2 -induced inflammation, edema, and fibrosis in bladder wall, concomitant with a significant decrease in mRNA expressions of inflammation biomarkers and a significant increase in endothelial nitric oxide synthase expression. HBO also inhibited the expression of transient receptor potential channels induced by H2 O2 instillation. CONCLUSION: These results suggest that HBO contributes to elimination of H2 O2 -induced long-lasting cystitis through the repair of chronically inflamed bladder tissue and inhibition of the bladder sensory system.

Comparison of efficacy and toxicity of second-line combination chemotherapy regimens in patients with advanced urothelial carcinoma.

BACKGROUND: The aim of this study was to evaluate the efficacy and toxicities of second-line chemotherapy regimens with docetaxel and gemcitabine (GD), or paclitaxel and gemcitabine (GP) for advanced or metastatic urothelial carcinoma (UC) that did not respond to first-line platinum-based chemotherapy. METHODS: From 2002 to 2017, 78 patients with metastatic UCs that progressed after platinum-based chemotherapy were treated with either GD (n = 41) or GP (n = 37). We compared these two different regimens by analyzing their efficacy and toxicities in a retrospective manner. RESULTS: Of the 78 patients enrolled in this study, it was possible to determine treatment efficacy in 70; the proportion of patients with objective response and disease control were 8.6 (9/70) and 54.3% (38/70), respectively. The median progression-free survival and overall survival in the total population (GP and GD) were 3.5 (95% CI 0.6-53.3) and 9.6 months (95% CI 1.2-53.3), respectively. There was no significant difference between the two regimens (GD or GP) regarding survival outcomes. Treatment-related adverse events were mostly manageable, but one patient died as a result of febrile neutropenia. The presence of liver metastasis and anemia (Hb < 10.0 g/dl) was prognostic factors for worse survival. CONCLUSIONS: Combination chemotherapy with either GP or GD was a favorable and well-tolerated second-line treatment regimen for patients with advanced or metastatic UC following the failure of a platinum-based regimen. Further study using a large prospective cohort is needed to identify patients who will benefit from second-line combination therapy.

Correlations of post-implant regional dosimetric parameters at 24 hours and one month, with clinical results of low-dose-rate brachytherapy for localized prostate cancer.

PURPOSE: To evaluate the correlations of post-implant regional dosimetrics at 24 hours (24 h) and 1 month after implant procedures, with clinical outcomes of low-dose-rate (LDR) brachytherapy for localized prostate cancer. MATERIAL AND METHODS: Between January 2008 and December 2014, 130 consecutive patients treated for localized prostate cancer, receiving definitive iodine-125 (125I) brachytherapy treatment were retrospectively analyzed. All patients underwent post-implant CT imaging for dosimetric analysis at 24 h and 1 month after implantation procedure. Prostate contours were divided into quadrants: anterior-superior (ASQ), posterior-superior (PSQ), anterior-inferior (AIQ), and posterior-inferior (PIQ). Predictive factors and cut-off values of biochemical failure-free survival (BFFS) and toxicities of LDR brachytherapy were analyzed. RESULTS: The median follow-up time was 69.5 months. Seven patients (5.4%) had biochemical failure. The 3-year and 5-year BFFS rates were 96.7% and 93.1%, respectively. On multivariate analysis, prostate-specific antigen and Gleason score were significant prognostic factors for biochemical failure. D90 (the minimal dose received by 90% of the volume) of PSQ and PIQ at 24 h, and D90 of PSQ at 1 month were also significant factors. The cut-off values of PSQ D90 were 145 Gy at 24 h and 160 Gy at 1 month. D90 of the whole prostate was not significant at 24 h and at 1 month. D90 of PSQ at 1 month was a significant factor for rectal hemorrhage. CONCLUSIONS: Post-implant D90 of PSQ is significantly associated with BFFS for localized prostate cancer not only at 1 month, but also at 24 hours. D90 of PSQ at 1 month is also a significant factor for rectal hemorrhage.

Efficacy of naftopidil for nocturia in male patients with lower urinary tract symptoms: comparison of morning and evening dosing.

OBJECTIVES: To examine the difference in improvement of lower urinary tract symptoms between morning and evening dosing of α1 -blocker naftopidil. METHODS: A total of 177 male patients with nocturia were included in the present study and randomized to morning or evening dosing of naftopidil. The International Prostate Symptom Score, quality of life index and nocturia quality of life index were compared between the two study groups at 12 weeks. RESULTS: A total of 143 patients (morning group: n = 70, evening group: n = 73) were analyzed as a result of the dropout of 34 patients because of failure to give consent, adverse events and failure to attend. Nocturia, quality of life index and nocturia quality of life index at 12 weeks were significantly better in the evening group compared with the morning group. In a multivariate model, both the dosing time of naftopidil and the initial nocturia quality of life index were significantly associated with change in nocturia quality of life index. CONCLUSIONS: Evening dosing of naftopidil seems to be more effective in treating nocturia in male patients with lower urinary tract symptoms.

Galectin 9 and PINCH, novel immunotherapy targets of renal cell carcinoma: a rationale to find potential tumour antigens and the resulting cytotoxic T lymphocytes induced by the derived peptides.

OBJECTIVE: To analyse and then generalize the mechanism by which partial or complete response is achieved among a limited number of patients with metastatic renal cell carcinoma (RCC) treated with interferon or interleukin-2. MATERIALS AND METHODS: An expression library of RCC (clear-cell carcinoma) was screened using the sera of patients with metastatic RCC who benefited from partial or complete response to cytokine therapy, the postulation being that those remarkable responders obtained specific cellular immunity against RCC with the antibodies to react with the cancer antigen. Peripheral blood mononuclear-cells (PBMCs) from healthy volunteers were stimulated with the antigen-derived peptides to induce specific cytotoxic T lymphocytes (CTLs). Specific activities of CTLs were measured by 5¹Cr-releasing assay. RESULTS: Among 15 positive clones isolated, two novel genes, galectin 9 and PINCH, were expressed at much higher levels in cancerous lesions than in normal tissues in all the patients with clear-cell carcinoma who were examined. Both HLA-A*2402-restricted and HLA-A*0201-restricted CTLs were induced by each antigen-derived peptide to exhibit specific and highly cytotoxic activities towards RCC cells. Specific CTLs were induced abundantly, as shown by flow cytometry analysis of the CTLs labelled with fluorescein isothiocyanate anti-CD107a and APC anti-CD8. The clonal expansion of the CTLs was shown by the clonality of T-cell receptor Vß repertoires. CONCLUSION: A novel approach based on clinical observations yielded promising tumour antigens as immunotherapy targets of RCC.

A Case of Pulmonary Pleomorphic Carcinoma With Renal Metastasis.

A 62-year-old man was referred to our hospital for an axillary mass. Computed tomography (CT) revealed a right axillary tumor and a left renal tumor. Needle biopsies of lung tumor and renal tumor were performed, but a definite diagnosis was impossible. Because his performance status worsened and the lung tumor grew day by day, chemotherapy with gemcitabine and cisplatin was started without definite diagnosis. However, the chemotherapy could not be continued because of interstitial pneumonia and the patient died because of the progression of disease. The final histopathologic diagnosis was pulmonary pleomorphic carcinoma based on immunohistochemical staining.

Suppressive Effects of Eviprostat, a Phytotherapeutic Agent, on Lower Urinary Tract Symptoms in Prostate Cancer Patients Treated with Brachytherapy.

OBJECTIVES: Eviprostat is an anti-oxidant, anti-inflammatory phytotherapeutic agent that is commonly used to treat lower urinary tract symptoms (LUTS) in benign prostatic hyperplasia in Japan and Germany. Prostate cancer patients treated with brachytherapy generally have complaints of LUTS for several months postoperatively. METHODS: We investigated the protective effects of Eviprostat against the development of LUTS in 37 patients, who had received (125) I prostate brachytherapy as monotherapy. These patients were divided into two groups, an Eviprostat-treated group (n = 18) and an untreated control (n = 19), whose background had no significant difference. The group treated with Eviprostat was prophylactically medicated from 3 weeks preoperatively until 3 months postoperatively. Symptom scores and quality of life for urination were evaluated according to the International Prostate Symptom Score (IPSS) and Expanded Prostate Cancer Index Composite (EPIC) on preoperative day 1, and postoperative months 1, 3 and 6. RESULTS: Both the scores of IPSS and the levels of quality of life in EPIC were significantly worse at 1 month postoperatively compared to the pretreatment baseline, and thereafter progressively improved in both groups. Eviprostat-treated patients showed significantly better recovery compared to Eviprostat-untreated control at 6 months postoperatively, with respect to urinary summary score, urinary function and urinary irritation/obstruction subscales in EPIC. Moreover, the feeling of incomplete emptying in IPSS and the urinary irritation/obstruction subscale in EPIC were significantly improved at 3 months postoperatively compared to the peak impairment at 1 month in the Eviprostat-treated group. CONCLUSIONS: It is possible that Eviprostat has the potential to ameliorate postoperative LUTS caused by brachytherapy.

[Successful combined treatment with maximal androgen blockade (MAB), intra arterial chemotherapy and radiation for advanced prostatic ductal adenocarcinoma : report of two cases].

The first case was in a 73-year-old man with macrohematuria. The second case was in a 59-year-old man with pollakiuria. Their serum prostate specific antigen levels were slightly elevated and urinary cytology was negative. Histological examination by prostatic needle biopsy and biopsy from bladder neck showed prostatic ductal adenocarcinoma. Clinical stage on computed tomography and magnetic resonance imaging was T4N0M0 in both cases. After 10-month maximal androgen blockade(MAB) and arterial chemotherapy using reservoir system, radiation therapy was performed. After that, low dose FP-chemotherapy(5-fluorouracil 600 mg/day, cisplatinum 10 mg/day) was performed for 28 days in the first case. At present, there are no signs of recurrence or metastasis in either case.

Expression of sphingosine-1 phosphate receptor in rat renal ischemia-reperfusion injury.

Sphingosine-1 phosphate receptor (S1PR) has come to the fore as a mediator of extracellular signaling through its interaction with G-protein-coupled receptors, which results in the induction of peripheral T-cell depletion. The mechanisms involved in renal ischemia-reperfusion (I/R) injury are complex, but appear to involve the early participation of bone marrow-derived cells, such as T lymphocytes. In this study, we investigated the expression of SIPR in a rat model of renal I/R injury. By means of a laparotomy, the right kidney was harvested and the left renal artery and vein were clamped. The kidney was reperfused after 90 min of ischemia, and rats were sacrificed at 0, 3, 6, 12 and 24 h after reperfusion. S1PR expression was analyzed by immunohistochemistry, and was observed only in endothelial cells of the normal kidneys. From 0 to 3 h after reperfusion, S1PR expression gradually became stronger in endothelial cells, reaching its peak intensity at 3 h after reperfusion. Twelve hours after reperfusion, necrosis had extended throughout the ischemic kidney, and nearly all the tubular epithelial cells had been destroyed. From 3 to 12 h after reperfusion, S1PR expression gradually weakened. At 24 h after reperfusion, levels of S1PR expression had almost reached those of the normal kidneys. In conclusion, S1PR was found to be expressed in a rat model of renal I/R injury. Several hours after achieving the maximum level of S1PR expression, the maximum level of renal I/R injury was observed. These results suggest a relationship between S1PR and renal I/R injury.

Telmisartan inhibits human urological cancer cell growth through early apoptosis.

Angiotensin II receptor blockers (ARBs) are widely used as hypertensive therapeutic agents. In addition, studies have provided evidence that ARBs have the potential to inhibit the growth of several types of cancer cells. It was reported that telmisartan (a type of ARB) has peroxisome proliferator-activated receptor (PPAR)-γ activation activity. We previously reported that the PPAR-γ ligand induces growth arrest in human urological cancer cells through apoptosis. In this study, we evaluated the effects of telmisartan and other ARBs on cell proliferation in renal cell carcinoma (RCC), bladder cancer (BC), prostate cancer (PC) and testicular cancer (TC) cell lines. The inhibitory effects of telmisartan and other ARBs (candesartan, valsartan, irbesartan and losartan) on the growth of the RCC, BC, PC and TC cell lines was investigated using an MTT assay. Flow cytometry and Hoechst staining were used to determine whether the ARBs induced apoptosis. Telmisartan caused marked growth inhibition in the urological cancer cells in a dose- and time-dependent manner. Urological cancer cells treated with 100 µM telmisartan underwent early apoptosis and DNA fragmentation. However, the other ARBs had no effect on cell proliferation in any of the urological cancer cell lines. Telmisartan may mediate potent anti-proliferative effects in urological cancer cells through PPAR-γ. Thus, telmisartan is a potent target for the prevention and treatment of human urological cancer.

Indirect antitumor effects of bisphosphonates on prostatic LNCaP cells co-cultured with bone cells.

Bisphosphonates are strong inhibitors of osteoclastic bone resorption in both benign and malignant bone diseases. The nitrogen-containing bisphosphonates (N-BPs) have strong cytotoxicity via inhibition of protein prenylation in the mevalonate pathway, and also demonstrate direct cytostatic and proapoptotic effects on prostate cancer cells. We confirmed the usefulness of a co-culture system comprised of prostatic LNCaP cells, ST2 cells (mouse-derived osteoblasts) and MLC-6 cells (mouse-derived osteoclasts) in vitro. N-BPs (pamidronate and zoledronic acid) inhibited both androgen receptor transactivation and tumor cell proliferation by suppressing the activities of both osteoclasts and osteoblasts with low-dose exposure. This indirect inhibition of prostate cancer cells via bone cells could be beneficial in treating prostate cancer patients with bone metastases.

Overexpression of orotate phosphoribosyl transferase in hormone-refractory prostate cancer.

Orotate phosphoribosyl transferase (OPRT) is the initial enzyme of 5-fluorouracil (5-FU) activation, in which 5-FU is converted to 5-fluorouridinemonophosphate. Dihydropyrimidine dehydrogenase (DPD) is a degrading enzyme that catabolizes 5-FU. In this study, we investigated the expression of these enzymes in normal prostate gland (NP), hormone-sensitive prostate cancer (HSPC) and hormone-refractory prostate cancer (HRPC). Forty-two prostatic tissue specimens were obtained from patients who had undergone prostate needle biopsies without any treatments or with PSA failure after initial androgen deprivation. The tissue samples derived from formalin-fixed, paraffin-embedded sections were made by laser-captured microdissection and from those RNA was extracted. The levels of OPRT and DPD mRNA expression were examined by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). The level of OPRT mRNA expression in the HSPC or the HRPC specimens was significantly higher than that in the NP specimens. Immunohistochemical staining for OPRT revealed strong expression of OPRT in prostate cancer cells. There was a significant correlation between OPRT mRNA expression levels and the tumor pathological grade. Furthermore, the OPRT/DPD expression ratio, a powerful predictive factor to evaluate 5-FU sensitivity, in the HRPC group was significantly higher than that in the low grade HSPC group. Thus, 5-FU may be an effective option for some HRPC patients.