Predicting clinically significant prostate cancer following suspicious mpMRI: analyses from a high-volume center.

PURPOSE: mpMRI is routinely used to stratify the risk of clinically significant prostate cancer (csPCa) in men with elevated PSA values before biopsy. This study aimed to calculate a multivariable risk model incorporating standard risk factors and mpMRI findings for predicting csPCa on subsequent prostate biopsy. METHODS: Data from 677 patients undergoing mpMRI ultrasound fusion biopsy of the prostate at the TUM University Hospital tertiary urological center between 2019 and 2023 were analyzed. Patient age at biopsy (67 (median); 33-88 (range) (years)), PSA (7.2; 0.3-439 (ng/ml)), prostate volume (45; 10-300 (ml)), PSA density (0.15; 0.01-8.4), PI-RADS (V.2.0 protocol) score of index lesion (92.2% ≥3), prior negative biopsy (12.9%), suspicious digital rectal examination (31.2%), biopsy cores taken (12; 2-22), and pathological biopsy outcome were analyzed with multivariable logistic regression for independent associations with the detection of csPCa defined as ISUP ≥ 3 (n = 212 (35.2%)) and ISUP ≥ 2 (n = 459 (67.8%) performed on 603 patients with complete information. RESULTS: Older age (OR: 1.64 for a 10-year increase; p < 0.001), higher PSA density (OR: 1.60 for a doubling; p < 0.001), higher PI-RADS score of the index lesion (OR: 2.35 for an increase of 1; p < 0.001), and a prior negative biopsy (OR: 0.43; p = 0.01) were associated with csPCa. CONCLUSION: mpMRI findings are the dominant predictor for csPCa on follow-up prostate biopsy. However, PSA density, age, and prior negative biopsy history are independent predictors. They must be considered when discussing the individual risk for csPCa following suspicious mpMRI and may help facilitate the further diagnostical approach.

The maximum standardized uptake value in patients with recurrent or persistent prostate cancer after radical prostatectomy and PSMA-PET-guided salvage radiotherapy-a multicenter retrospective analysis.

PURPOSE: This study aims to evaluate the association of the maximum standardized uptake value (SUVmax) in positron-emission tomography targeting prostate-specific membrane antigen (PSMA-PET) prior to salvage radiotherapy (sRT) on biochemical recurrence free survival (BRFS) in a large multicenter cohort. METHODS: Patients who underwent 68 Ga-PSMA11-PET prior to sRT were enrolled in four high-volume centers in this retrospective multicenter study. Only patients with PET-positive local recurrence (LR) and/or nodal recurrence (NR) within the pelvis were included. Patients were treated with intensity-modulated-sRT to the prostatic fossa and elective lymphatics in case of nodal disease. Dose escalation was delivered to PET-positive LR and NR. Androgen deprivation therapy was administered at the discretion of the treating physician. LR and NR were manually delineated and SUVmax was extracted for LR and NR. Cox-regression was performed to analyze the impact of clinical parameters and the SUVmax-derived values on BRFS. RESULTS: Two hundred thirty-five patients with a median follow-up (FU) of 24 months were included in the final cohort. Two-year and 4-year BRFS for all patients were 68% and 56%. The presence of LR was associated with favorable BRFS (p = 0.016). Presence of NR was associated with unfavorable BRFS (p = 0.007). While there was a trend for SUVmax values ≥ median (p = 0.071), SUVmax values ≥ 75% quartile in LR were significantly associated with unfavorable BRFS (p = 0.022, HR: 2.1, 95%CI 1.1-4.6). SUVmax value in NR was not significantly associated with BRFS. SUVmax in LR stayed significant in multivariate analysis (p = 0.030). Sensitivity analysis with patients for who had a FU of > 12 months (n = 197) confirmed these results. CONCLUSION: The non-invasive biomarker SUVmax can prognosticate outcome in patients undergoing sRT and recurrence confined to the prostatic fossa in PSMA-PET. Its addition might contribute to improve risk stratification of patients with recurrent PCa and to guide personalized treatment decisions in terms of treatment intensification or de-intensification. This article is part of the Topical Collection on Oncology-Genitourinary.

ENERGIZE: a Phase III study of neoadjuvant chemotherapy alone or with nivolumab with/without linrodostat mesylate for muscle-invasive bladder cancer.

Immune checkpoint inhibitors have revolutionized the treatment of patients with metastatic urothelial carcinoma. In cisplatin-eligible muscle-invasive bladder cancer (MIBC), cisplatin-based neoadjuvant chemotherapy (NAC) before radical cystectomy improves overall survival. Tumor PD-L1 expression increases in MIBC after NAC, suggesting potential synergy in combining PD1/PD-L1 inhibitors with NAC. IDO1 is overexpressed in bladder cancer and is associated with poor outcomes. Linrodostat mesylate (BMS-986205) - a selective, potent, oral IDO1 inhibitor - combined with nivolumab has demonstrated safety and preliminary evidence of clinical activity in metastatic urothelial carcinoma. Here, we discuss the rationale and trial design of the ENERGIZE, a Phase III trial investigating the efficacy of NAC in combination with nivolumab with or without linrodostat followed by postsurgery nivolumab or nivolumab with linrodostat in cisplatin-eligible patients with MIBC. Clinical trial registration number: NCT03661320.

STAT3/5 Inhibitors Suppress Proliferation in Bladder Cancer and Enhance Oncolytic Adenovirus Therapy.

The JAK-STAT signalling pathway regulates cellular processes like cell division, cell death and immune regulation. Dysregulation has been identified in solid tumours and STAT3 activation is a marker for poor outcome. The aim of this study was to explore potential therapeutic strategies by targeting this pathway in bladder cancer (BC). High STAT3 expression was detected in 51.3% from 149 patient specimens with invasive bladder cancer by immunohistochemistry. Protein expression of JAK, STAT and downstream targets were confirmed in 10 cell lines. Effects of the JAK inhibitors Ruxolitinib and BSK-805, and STAT3/5 inhibitors Stattic, Nifuroxazide and SH-4-54 were analysed by cell viability assays, immunoblotting, apoptosis and cell cycle progression. Treatment with STAT3/5 but not JAK1/2 inhibitors reduced survival, levels of phosphorylated STAT3 and Cyclin-D1 and increased apoptosis. Tumour xenografts, using the chicken chorioallantoic membrane (CAM) model responded to Stattic monotherapy. Combination of Stattic with Cisplatin, Docetaxel, Gemcitabine, Paclitaxel and CDK4/6 inhibitors showed additive effects. The combination of Stattic with the oncolytic adenovirus XVir-N-31 increased viral replication and cell lysis. Our results provide evidence that inhibitors against STAT3/5 are promising as novel mono- and combination therapy in bladder cancer.

Men with family history of prostate cancer have a higher risk of disease recurrence after radical prostatectomy.

PURPOSE: We aimed to determine if family history (FH) of prostate cancer (PC) influenced cancer control after radical prostatectomy (RP). METHODS: Patients were evaluated in a prospectively-collected PC family database: The focus was on hereditary prostate cancer (HPC) defined by Johns Hopkins criteria and sporadic prostate cancer (SPC), rigorously defined by absence of prostate cancer in ≥ 2 brothers aged ≥ 60 years. Additionally, patients with first-degree (FPC) and non-first-degree PC (non-FPC) were assessed. Endpoints were biochemical recurrence-free survival (BRFS) and prostate cancer-specific survival (CSS). Finally, clinico-pathological characteristics were compared and multiple proportional hazards regression was used to identify prognostic factors. RESULTS: In total 11,654 patients were included (807 HPC, 2251 FPC, 8072 non-FPC and 524 SPC). Familial imposition (HPC/FPC) was associated with a younger age at diagnosis. Thus, HPC patients were diagnosed 2.9 years earlier than SPC patients with more locally advanced tumors (≥ pT3). With a median follow up of 6.2 years (range 0-31.5) BRFS was significantly different when stratified by FH. In pairwise analyses BRFS differed significantly for HPC compared to SPC (HR = 1.27). Consecutively FH was identified as prognostic factor for BRFS (p = 0.021) together with age, PSA, pathologic characteristics and adjuvant androgen deprivation. Analyses of CSS did not show a difference. CONCLUSION: Patients with FH of PC are likely to be diagnosed earlier and present a higher proportion of locally advanced disease. In addition, men with FH are at higher risk of biochemical recurrence after surgery but reveal similar outcomes regarding prostate cancer-specific survival.

Prognostic Factors for Biochemical Recurrence More than 10 Years after Radical Prostatectomy.

PURPOSE: Some patients with long postoperative intervals of undetectable prostate specific antigen are still at risk for biochemical recurrence. Our aims were to identify prognostic factors for late biochemical recurrence, including cancer family history, and evaluate cancer specific mortality. MATERIALS AND METHODS: We identified 10,310 patients after radical prostatectomy without neoadjuvant or adjuvant therapy between 1979 and 2015 in the prospective German Familial Prostate Cancer database. A subgroup of 2,480 patients with more than 10 years of followup (median 12.8) had undetectable prostate specific antigen. Biochemical recurrence, defined as prostate specific antigen 0.2 ng/ml or greater, developing at more than 10 years was defined as late biochemical recurrence. Multiple proportional hazards regression with forward selection was applied to determine prognostic factors for late biochemical recurrence. RESULTS: The Kaplan-Meier estimated biochemical recurrence rate at 10, 15 and 20 years was 34.3%, 44.0% and 52.7%, respectively. Of 2,480 patients with undetectable prostate specific antigen 10 years postoperatively 249 subsequently had biochemical recurrence, of whom 12 died of prostate cancer. The factors associated with late biochemical recurrence were age at surgery (HR 1.04 per year, p = 0.027), prostate specific antigen at diagnosis (HR 1.02 per ng/ml, p = 0.020), pathological Gleason score (categorical 2-6 vs 7 [3 + 4], 7, 7 [4 + 3] and 8-10, p = 0.002) and pathological tumor stage pT3a or greater (HR 1.50, p = 0.065). CONCLUSIONS: From years 10 to 15 and 10 to 20 postoperatively the biochemical recurrence rate increased by 9.7% and 18.4%, respectively. In contrast to a family history of prostate cancer, age at surgery, prostate specific antigen at diagnosis, pathological tumor stage and pathological Gleason score were prognostic factors for late biochemical recurrence. Patients with late biochemical recurrence are still at risk for death from prostate cancer.

No Detrimental Effect of a Positive Family History on Long-Term Outcomes Following Radical Prostatectomy.

PURPOSE: Overall 1 in 5 patients with prostate cancer has a positive family history. In this report we evaluated the association between family history and long-term outcomes following radical prostatectomy. MATERIALS AND METHODS: Patients treated with radical prostatectomy were identified from a German registry, and separated into positive first-degree family history vs negative family history (strictly negative, requiring at least 1 male first-degree relative older than 60 years and no prostate cancer in the family). Kaplan-Meier curves and Cox proportional hazards models were used for association analyses with biochemical recurrence-free and prostate cancer specific survival. RESULTS: Median followup for 7,690 men included in the study was 8.4 years. Of the 754 younger patients less than 55 years old 50.9% (384) had a family history compared to 40.4% of the older patients (2,803; p <0.001). The 10-year biochemical recurrence-free (62.5%) and prostate cancer specific survival (96.1%) rates did not differ between patients with vs without a family history, nor between the younger vs older patient groups (all p >0.05). Prostate specific antigen, pathological stage, node stage and Gleason score were the only significant predictors for biochemical recurrence-free survival, while pathological stage, node stage (all p <0.005) and Gleason score (Gleason 7 vs 6 or less-HR 1.711, 95% CI 1.056-2.774, p = 0.03; Gleason 8 or greater vs 6 or less-HR 4.516, 95% CI 2.776-7.347, p <0.0001) were the only predictors for prostate cancer specific survival. CONCLUSIONS: A family history of prostate cancer has no bearing on long-term outcomes after radical prostatectomy.

CDK4/6 Inhibition Controls Proliferation of Bladder Cancer and Transcription of RB1.

PURPOSE: The retinoblastoma signaling network is frequently altered in advanced bladder cancer. We investigated the potential of CDK4/6 as a therapeutic target and determined biomarkers for patient stratification. MATERIALS AND METHODS: Genetic alterations were analyzed using public databases, including TCGA (The Cancer Genome Atlas), COSMIC (Catalogue of Somatic Mutations in Cancer) and CCLE (Cancer Cell Line Encyclopedia). Effects of the CDK4/6-inhibitor PD-0332991 or LY2835219 were examined in 10 bladder cancer cell lines by immunoblot, cell viability, apoptosis and cell cycle progression. Efficacy of the PD-0332991 and cisplatin combination was analyzed using the combination index. Gene expression level was determined by quantitative polymerase chain reaction. Cytomegalovirus promoter regulated recombinant retinoblastoma was used for reconstitution. Three-dimensional xenografts were grown on chicken chorioallantoic membrane and analyzed by measuring tumor weight and immunohistochemical expression of total retinoblastoma and Ki-67. RESULTS: PD-0332991 treatment decreased the proliferation of retinoblastoma positive bladder cancer cell lines and was synergistic in combination with cisplatin. PD-0332991 or LY2835219 treatment decreased the phosphorylation, total protein and transcript level of retinoblastoma. Treatment resulted in a decrease in E2F target gene expression (CCNA2 and CCNE2) and cell cycle progression from G0/G1 to the S-phase but did not affect apoptosis. In retinoblastoma negative cells reconstituted with recombinant retinoblastoma PD-0332991 affected only phosphorylation and not the total retinoblastoma level. These cells remained resistant to treatment. In 3-dimensional retinoblastoma xenografts, treatment resulted in reduced tumor weight and decreased expression of total retinoblastoma and Ki-67. CONCLUSIONS: We provide preclinical evidence that CDK4/6 inhibition is a potential therapeutic strategy for retinoblastoma positive bladder cancer that probably acts by negatively regulating retinoblastoma transcription.

Docetaxel and prednisone with or without lenalidomide in chemotherapy-naive patients with metastatic castration-resistant prostate cancer (MAINSAIL): a randomised, double-blind, placebo-controlled phase 3 trial.

BACKGROUND: Patients with metastatic castration-resistant prostate cancer have few treatment options. We investigated the safety and efficacy of lenalidomide, an immunomodulatory agent with anti-angiogenic properties, in combination with docetaxel and prednisone in chemotherapy-naive patients with metastatic castration-resistant prostate cancer. METHODS: In this randomised, double-blind, placebo-controlled, phase 3 study, we randomly assigned chemotherapy-naive patients with progressive metastatic castration-resistant prostate cancer in a 1:1 ratio to receive docetaxel (75 mg/m(2)) on day 1 and prednisone (5 mg twice daily) on days 1-21 and either lenalidomide (25 mg) or placebo once daily on days 1-14 of each 21 day treatment cycle. Permuted block randomisation was done with an interactive voice response system and stratified by Eastern Cooperative Oncology Group performance status, geographic region, and type of disease progression. Clinicians, patients, and investigators were masked to treatment allocation. The primary endpoint was overall survival. Efficacy analysis was by intention to treat. Patients who received at least one dose of study drug were included in the safety analyses. This study is registered with ClinicalTrials.gov, number NCT00988208. FINDINGS: 1059 patients were enrolled and randomly assigned between Nov 11, 2009, and Nov 23, 2011 (533 to the lenalidomide group and 526 to the control group), and 1046 patients received study treatment (525 in the lenalidomide group and 521 in the placebo group). At data cutoff (Jan 13, 2012) after a median follow-up of 8 months (IQR 5-12), 221 patients had died: 129 in the lenalidomide group and 92 in the placebo group. Median overall survival was 17·7 months (95% CI 14·8-18·8) in the lenalidomide group and not reached in the placebo group (hazard ratio [HR] 1·53, 95% CI 1·17-2·00, p=0·0017). The trial was subsequently closed early due to futility. The number of deaths that occurred during treatment or less than 28 days since the last dose were similar in both groups (18 [3%] of 525 patients in the lenalidomide group vs 13 [2%] of 521 patients). 109 (21%) patients in the lenalidomide group and 78 (15%) in the placebo group died more than 28 days from last dose, mainly due to disease progression. At least one grade 3 or higher adverse event was reported in 381 (73%) of 525 patients receiving lenalidomide and 303 (58%) of 521 patients receiving placebo. Grade 3-4 neutropenia (114 [22%] for lenalidomide vs 85 [16%] for placebo), febrile neutropenia (62 [12%] vs 23 [4%]), diarrhoea (37 [7%] vs 12 [2%]), pneumonia (24 [5%] vs five [1%]), dyspnoea (22 [4%] vs nine [2%]), asthenia (27 [5%] vs 17 [3%]), and pulmonary embolism (32 [6%] vs seven [1%]) occurred more frequently in the lenalidomide group than in the placebo group. INTERPRETATION: Overall survival with the combination of lenalidomide, docetaxel, and prednisone was significantly worse than with docetaxel and prednisone for chemotherapy-naive men with metastatic, castration-resistant prostate cancer. Further research with this treatment combination is not warranted. FUNDING: Celgene Corporation.

11C-Choline PET/pathology image coregistration in primary localized prostate cancer.

PURPOSE: The aim of this study was to develop a methodology for the comparison of pathology specimens after prostatectomy (post-S) with PET images obtained before surgery (pre-S). This method was used to evaluate the merit of (11)C-choline PET/CT for delineation of gross tumour volume (GTV) in prostate cancer (PC). METHODS: In 28 PC patients, (11)C-choline PET/CT was performed before surgery. PET/CT data were coregistered with the pathology specimens. GTV on PET images (GTV-PET) was outlined automatically and corrected manually. Tumour volume in the prostate (TVP) was delineated manually on the pathology specimens. Based on the coregistered PET/pathology images, the following parameters were assessed: SUVmax and SUVmean in the tumoral and nontumoral prostate (NP), GTV-PET (millilitres) and TVP (millilitres). RESULTS: PET/pathology image coregistration was satisfactory. Mean SUVmax in the TVP was lower than in the NP: 5.0 and 5.5, respectively (p = 0.093). Considering the entire prostate, SUVmax was located in the TVP in two patients, in the TVP and NP in 12 patients and exclusively in NP in 14 patients. Partial overlap the TVP and GTV-PET was seen in 71% of patients, and complete overlap in 4%. CONCLUSION: PET/pathology image coregistration can be used for evaluation of different imaging modalities. (11)C-Choline PET failed to distinguish tumour from nontumour tissue.

Prevalence of bilateral loco-regional spread in unilateral pelvic PSMA PET positive recurrent prostate cancer.

BACKGROUND: Defining the best surgical template for salvage lymph node dissection (SLND) in patients exhibiting unilateral prostate cancer (PCa) recurrence in pelvic lymph nodes (LNs) is an unmet need. We assessed the risk of missing contralateral nodal recurrence in patients with unilateral positive PSMA-PET who were treated with bilateral PSMA-radioguided (RGS) SLND. METHODS: Patients who consecutively underwent bilateral PSMA-radioguided SLND for PCa recurrence between April 2014 and January 2023 were identified. We compared PSMA PET findings with the number and the location of PCa LN metastases of the final pathological report. Univariable logistic regression models to try to predict contralateral missed disease were performed. RESULTS: Sixty patients were identified. At PSMA-RGS, the median PSA level was 0.71 ng/mL (IQR: 0.38-2.28). At PSMA-PET pre-SLND, 49 (82%) patients had unilateral exclusively pelvic lesions, 2 (3%) had unilateral positive nodes at the level of the common iliac arteries, and 9 (15%) had unilateral positive nodes in both levels. Final pathology revealed unilateral LN involvement in 43 (72%), a negative report in 3 (5%), and bilateral positive lesions in 14 (23%) patients. In the univariable logistic regression models, none of the tested factors showed influence on missing contralateral lesions. Four patients out of 35 (11%) with one positive LN at PSMA-PET had bilateral PCa recurrence. CONCLUSIONS: Patients with one-sided positive LNs on PSMA PET can be considered for a unilateral PSMA-radioguided SLND template with the caveat that about a quarter of patients ultimately have bilateral positive LNs. Larger prospective randomized trials are needed to confirm our findings.

Gender and body mass index as risk factors for bladder perforation during primary transurethral resection of bladder tumors.

PURPOSE: Bladder cancer is the second most common tumor of the genitourinary system. Although transurethral resection is the standard diagnostic and therapeutic procedure, it is not morbidity free. Bladder perforation is the second most common complication and it can lead to severe further complications. We evaluated risk factors for bladder perforation in patients treated with transurethral resection of bladder tumors. MATERIALS AND METHODS: We retrospectively studied the records of 1,284 patients with bladder cancer who underwent transurethral resection of bladder tumors between 1986 and 2006. Data on risk factors for bladder perforation, including age, gender, body mass index, nicotine use, gross hematuria, transurethral catheterization, bladder stones, tumor stage and grade, number of tumors and resection weight, were analyzed with the chi-square or Fisher exact test. RESULTS: Of the 49 bladder perforations (3.8%) 89.8% were extraperitoneal and 10.2% were intraperitoneal. The risk of bladder perforation was associated with gender (female and male 7.2% and 2.6%, p <0.001), body mass index (less than 25, 25 to 30 and greater than 30 kg/m(2) 5.5%, 3.4% and 0.6%, p = 0.016), tumor stage (pTis, pTa, pT1 and pT2 or greater 3.7%, 2.6%, 4.5% and 6.7%, p = 0.049), infiltration depth (superficial and muscle invasive 3.2% and 6.6%, p = 0.023) and resection weight (less than 2.5 and 20 gm or greater 2.4% and 9.2%, respectively, p = 0.003). Patient age, nicotine use, gross hematuria at diagnosis, transurethral catheterization, bladder stones, number of tumors and tumor grade were not risk factors for bladder perforation. CONCLUSIONS: Aside from tumor characteristics female gender and low body mass index were risk factors for inadvertent bladder perforation during transurethral resection of bladder tumors. Each factor is readily apparent.

Ileal neobladder in women with bladder cancer: cancer control and functional aspects.

PURPOSE OF REVIEW: Radical cystectomy and urinary diversion is the accepted standard of care for invasive bladder cancer. Although orthotopic neobladder is the preferred method of urinary diversion in men, less experience is available for women. Recent studies and reports on this subject are summarized and reviewed. RECENT FINDINGS: Urethra-sparing cystectomy in women and orthotopic urinary diversion can be performed safely in appropriately selected women with invasive bladder cancer. Excellent oncological outcomes can be expected with a minimal risk of urethral recurrence in case of negative frozen section of the proximal urethra. Orthotopic neobladder diversion offers excellent clinical and functional results, and should be the diversion of choice in most women following cystectomy. Female sexual dysfunction can be avoided in patients who received neurovascular preservation, although quality of life declined in women who had undergone non-nerve-sparing radical cystectomy. SUMMARY: Urethra-sparing cystectomy does not compromise the oncologic outcome in women with bladder cancer. The excellent functional outcome and voiding pattern with orthotopic urinary diversion argues in favor of this technique as the preferred method for lower urinary tract reconstruction after radical cystectomy. Nerve-sparing radical cystectomy preserves female sexual function and improves quality of life.

Functional genomics identifies predictive markers and clinically actionable resistance mechanisms to CDK4/6 inhibition in bladder cancer.

BACKGROUND: CDK4/6 inhibitors are a promising treatment strategy in tumor therapy but are hampered by resistance mechanisms. This study was performed to reveal predictive markers, mechanisms of resistance and to develop rational combination therapies for a personalized therapy approach in bladder cancer. METHODS: A genome-scale CRISPR-dCas9 activation screen for resistance to the CDK4/6 inhibitor Palbociclib was performed in the bladder cancer derived cell line T24. sgRNA counts were analyzed using next generation sequencing and MAGeCK-VISPR. Significantly enriched sgRNAs were cloned and validated on a molecular and functional level for mediating resistance to Palbociclib treatment. Analysis was done in vitro and in vivo in the chorioallantois membrane model of the chicken embryo. Comparison of screen hits to signaling pathways and clinically relevant molecular alterations was performed using DAVID, Reactome, DGIdb and cBioPortal. RESULTS: In the screen, 1024 sgRNAs encoding for 995 genes were significantly enriched indicative of mediators of resistance. 8 random sgRNAs were validated, revealing partial rescue to Palbociclib treatment. Within this gene panel, members of Receptor-Tyrosine Kinases, PI3K-Akt, Ras/MAPK, JAK/STAT or Wnt signaling pathways were identified. Combination of Palbociclib with inhibitors against these signaling pathways revealed beneficial effects in vitro and in in vivo xenografts. CONCLUSIONS: Identification of potential predictive markers, resistance mechanisms and rational combination therapies could be achieved by applying a CRISPR-dCas9 screening approach in bladder cancer.

5-aza-2'-deoxycytidine delays androgen-independent disease and improves survival in the transgenic adenocarcinoma of the mouse prostate mouse model of prostate cancer.

PURPOSE: We have previously shown that 5-aza-2'-deoxycytidine (5-aza) is an effective chemopreventive agent capable of preventing early disease progression in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model. The purpose of this study was to determine the effect of 5-aza on preexisting TRAMP prostate cancers and prevention of androgen-independent prostate cancer. EXPERIMENTAL DESIGN: TRAMP mice with established prostate cancers were treated with 5-aza, castration, castration + 5-aza, or vehicle control (PBS). One cohort of 22 mice per treatment was euthanized after 10 weeks of treatment, whereas a second cohort of 14 mice per group was followed until death to determine survival. Histologic sections of prostate, pelvic lymph nodes, lung, and liver were blinded and analyzed by a certified genitourinary pathologist (K.J.W.). RESULTS: Combined treatment (castration + 5-aza) provided significant survival benefits over either single treatment (combined versus castration P = 0.029, combined versus 5-aza P = 0.036). At 24 weeks of age, 86% of mice within the PBS cohort exhibited histologic evidence of prostate cancer, whereas only 47% of the combined cohort exhibited malignant disease (P < 0.0001). Additionally, whereas 43% of the PBS treatment group exhibited lymph node metastases, these were only observed in 21% of the combined treatment mice. CONCLUSIONS: This is the first study to examine the effect of 5-aza and combined castration + 5-aza on preexisting prostate cancer in an animal model. Based on these preclinical findings, we suggest that 5-aza treatment may prolong the time to an androgen-independent status and thus survival in a hormone-deprived setting in prostate cancer.

Parallel PI3K, AKT and mTOR inhibition is required to control feedback loops that limit tumor therapy.

Targeting the PI3K pathway has achieved limited success in cancer therapy. One reason for the disappointing activity of drugs that interfere with molecules that are important player in this pathway is the induction of multiple feedback loops that have been only partially understood. To understand these limitations and develop improved treatment strategies, we comprehensively characterized molecular mechanisms of PI3K pathway signaling in bladder cancer cell lines upon using small molecule inhibitors and RNAi technologies against all key molecules and protein complexes within the pathway and analyzed functional and molecular consequences. When targeting either mTORC1, mTOR, AKT or PI3K, only S6K1 phosphorylation was affected in most cell lines examined. Dephosphorylation of 4E-BP1 required combined inhibition of PI3K and mTORC1, independent from AKT, and resulted in a robust reduction in cell viability. Long-term inhibition of PI3K however resulted in a PDK1-dependent, PIP3 and mTORC2 independent rephosphorylation of AKT. AKT rephosphorylation could also be induced by mTOR or PDK1 inhibition. Combining PI3K/mTOR inhibitors with AKT or PDK1 inhibitors suppressed this rephosphorylation, induced apoptosis, decreased colony formation, cell viability and growth of tumor xenografts. Our findings reveal novel molecular mechanisms that explain the requirement for simultaneous targeting of PI3K, AKT and mTORC1 to achieve effective tumor growth inhibition.

Prostate-specific membrane antigen expression as a predictor of prostate cancer progression.

Distinguishing aggressive prostate cancer from indolent disease represents an important clinical challenge, because current therapy may lead to overtreatment of men with limited disease. The prostate-specific membrane antigen (PSMA) is a membrane-bound glycoprotein that is highly restricted to the prostate. Previously, studies analyzing the expression of PSMA have found an up-regulation in correlation with prostate cancer, particularly in advanced cancer. This association is ideal for an application as a prognostic marker. In the current study, we characterized PSMA expression in a high-risk cohort and evaluated its potential use as predictive marker of prostate-specific antigen (PSA) recurrence. PSMA expression was analyzed by immunohistochemistry using tissue microarrays composed of tumor samples from 450 patients. Protein intensity was recorded using a semiautomated quantitative microscope system (ACIS II; Clarient Chromavision Medical Systems, San Juan Capistrano, CA). PSMA expression levels differed significantly (P < .001) between benign prostatic tissue, localized prostate cancer, and lymph node metastases. Dividing the cohort into high- and low-PSMA expressing cancers based on the median area of positive staining, we found that high PSMA levels were associated with significant increase of PSA recurrence (P = .004). This was independent of clinical parameters such as lymph node tumor burden (lymph node density, >20%; P < .001), extraprostatic extension (P = .017), seminal vesicle invasion (P < .001), and high Gleason score (8-10, P = .006). In a multivariate model, PSMA expression and metastases to pelvic lymph nodes were significantly associated with time to PSA recurrence (HR, 1.4; 95% confidence interval, 1.1-2.8, P = .017; and hazard ratio, 5; 95% confidence interval, 2.6-9.7, P < .001, respectively). In summary, PSMA is independently associated with PSA recurrence in a high-risk cohort and thus might provide insight into the additional use of adjuvant therapy. Validation on other cohorts is required.

Tissue engineered venous matrices for potential applications in the urogenital tract.

Tissue engineering is lacking inexpensive, easily applicable techniques for tissue replacement. We investigated the potential use of native veins for tissue-engineering applications in the urological field. Forty-eight porcine veins, half seeded with urothelial cells and half unseeded, were kept in vitro for 7 days. Four seeded and four unseeded scaffolds were analyzed after 3 and 7 days. The remaining 32 veins were implanted subcutaneously into 16 athymic mice. Four athymic mice were sacrificed after 2, 4, 8, and 12 weeks. Histochemistry, immunohistochemistry (anti-pancytokeratin AE1/AE3, anti-desmin), western blot analyses (CD31), and scanning electron microscopy were performed in the retrieved specimens. The histochemistry of the seeded matrices showed the presence of urothelial cells in vitro and in vivo. After 12 weeks, a multilayer of urothelial cells was present in the hemotoxylin and eosin staining, positive for anti-pancytokeratin AE1/AE3. The western blot analyses showed vascularization of the veins in vivo. The results of scanning electron microscopy revealed a cellular layer on the veins. Native venous matrices may be used as tissue-engineered constructs for reconstructing the urinary tract. The clinical relevance of this approach must be proven in a large-animal model.

Association of Survival Benefit With Docetaxel in Prostate Cancer and Total Number of Cycles Administered: A Post Hoc Analysis of the Mainsail Study.

IMPORTANCE: The optimal total number of docetaxel cycles in patients with metastatic castration resistant prostate cancer (mCPRC) has not been investigated yet. It is unknown whether it is beneficial for patients to continue treatment upon 6 cycles. OBJECTIVE: To investigate whether the number of docetaxel cycles administered to patients deriving clinical benefit was an independent prognostic factor for overall survival (OS) in a post hoc analysis of the Mainsail trial. DESIGN, SETTING, AND PARTICIPANTS: The Mainsail trial was a multinational randomized phase 3 study of 1059 patients with mCRPC receiving docetaxel, prednisone, and lenalidomide (DPL) or docetaxel, prednisone, and a placebo (DP). Study patients were treated until progressive disease or unacceptable adverse effects occurred. Median OS was found to be inferior in the DPL arm compared with the DP arm. As a result of increased toxic effects with the DPL combination, patients on DPL received fewer docetaxel cycles (median, 6) vs 8 cycles in the control group. As the dose intensity was comparable in both treatment arms, we investigated whether the number of docetaxel cycles administered to patients deriving clinical benefit on Mainsail was an independent prognostic factor for OS. We conducted primary univariate and multivariate analyses for the intention-to-treat population. Additional sensitivity analyses were done, excluding patients who stopped treatment for reasons of disease progression and those who received 4 or fewer cycles of docetaxel for other reasons, minimizing the effect of confounding factors. MAIN OUTCOMES AND MEASURES: Total number of docetaxel cycles delivered as an independent factor for OS. RESULTS: Overall, all 1059 patients from the Mainsail trial were included (mean [SD] age, 68.7 [7.89] years). Treatment with 8 or more cycles of docetaxel was associated with superior OS (hazard ratio [HR], 1.909; 95% CI, 1.660-2.194; P < .001), irrespective of lenalidomide treatment (HR, 1.060; 95% CI, 0.924-1.215; P = .41). Likewise, in the sensitivity analysis, patients who received a greater number of docetaxel cycles had superior OS; patients who received more than 10 cycles had a median OS of 33.0 months compared with 26.9 months in patients treated with 8 to 10 cycles; and patients who received 5 to 7 cycles had a median OS of 22.8 months (P < .001). CONCLUSIONS AND RELEVANCE: These findings suggest that continuation of docetaxel chemotherapy contributes to the survival benefit. Prospective validation is warranted.

Inhibition of clonogenic tumor growth: a novel function of Smac contributing to its antitumor activity.

While second mitochondria derived activator of caspase (Smac) has been described to sensitize for apoptosis, its effect on cell viability in the absence of apoptotic stimuli has remained unclear. Here, we report that Smac inhibits clonogenic tumor growth by blocking random migration and proliferation and by enhancing apoptosis in a cell density and cell type dependent manner in SH-EP neuroblastoma cells. Inhibition of clonogenic survival by overexpression of full-length or processed Smac strictly depended on low cell density, and was reversible by replatement at high density. We discovered that Smac inhibits cell motility and random migration at low cell density. In addition, Smac enhanced apoptosis and inhibited protein, but not mRNA expression of XIAP, survivin and other short-lived proteins (FLIP, p21), indicating that Smac may globally inhibit protein expression. Also, Smac inhibited proliferation and increased polynucleation with no evidence for polyploidy, cell cycle arrest or senescence indicating that Smac impaired cell division. Interestingly, inhibition of clonogenic capacity by Smac occurred independent of its apoptosis promoting activity. By demonstrating that Smac restrains clonogenic tumor growth, our findings may have important implications for control of tumor growth and/or its metastatic spread. Thus, Smac agonists may be useful in cancer therapy, for example, for tumor control in minimal residual disease. Oncogene (2005) 24, 7190-7202. doi:10.1038/sj.onc.1208876; published online 8 August 2005.