Sven Wenske

NF-κB Regulates Androgen Receptor Expression and Prostate Cancer Growth

Prostate cancers that progress during androgen-deprivation therapy often overexpress the androgen receptor (AR) and depend on AR signaling for growth. In most cases, increased AR expression occurs without gene amplification and may be due to altered transcriptional regulation. The transcription factor nuclear factor (NF)-kappaB, which is implicated in tumorigenesis, functions as an important downstream substrate of mitogen-activated protein kinase, phosphatidylinositol 3-kinase, AKT, and protein kinase C and plays a role in other cancer-associated signaling pathways. NF-kappaB is an important determinant of prostate cancer clinical biology, and therefore we investigated its role in the regulation of AR expression. We found that NF-kappaB expression in prostate cancer cells significantly increased AR mRNA and protein levels, AR transactivation activity, serum prostate-specific antigen levels, and cell proliferation. NF-kappaB inhibitors decrease AR expression levels, prostate-specific antigen secretion, and proliferation of prostate cancer cells in vitro. Furthermore, inhibitors of NF-kappaB demonstrated anti-tumor activity in androgen deprivation-resistant prostate cancer xenografts. In addition, levels of both NF-kappaB and AR were strongly correlated in human prostate cancer. Our data suggest that NF-kappaB can regulate AR expression in prostate cancer and that NF-kappaB inhibitors may have therapeutic potential.

Circulating Prostate Tumor Cells Detected by Reverse Transcription-PCR in Men with Localized or Castration-Refractory Prostate Cancer: Concordance with CellSearch Assay and Association with Bone Metastases and with Survival

BACKGROUND Reverse transcription-PCR (RT-PCR) assays have been used for analysis of circulating tumor cells (CTCs), but their clinical value has yet to be established. We assessed men with localized prostate cancer or castration-refractory prostate cancer (CRPC) for CTCs via real-time RT-PCR assays for KLK3 [kallikrein-related peptidase 3; i.e., prostate-specific antigen (PSA)] and KLK2 mRNAs. We also assessed the association of CTCs with disease characteristics and survival. METHODS KLK3, KLK2, and PSCA (prostate stem cell antigen) mRNAs were measured by standardized, quantitative real-time RT-PCR assays in blood samples from 180 localized-disease patients, 76 metastatic CRPC patients, and 19 healthy volunteers. CRPC samples were also tested for CTCs by an immunomagnetic separation system (CellSearch; Veridex) approved for clinical use. RESULTS All healthy volunteers were negative for KLK mRNAs. Results of tests for KLK3 or KLK2 mRNAs were positive (> or =80 mRNAs/mL blood) in 37 patients (49%) with CRPC but in only 15 patients (8%) with localized cancer. RT-PCR and CellSearch CTC results were strongly concordant (80%-85%) and correlated (Kendall tau, 0.60-0.68). Among CRPC patients, KLK mRNAs and CellSearch CTCs were closely associated with clinical evidence of bone metastases and with survival but were only modestly correlated with serum PSA concentrations. PSCA mRNA was detected in only 7 CRPC patients (10%) and was associated with a positive KLK mRNA status. CONCLUSIONS Real-time RT-PCR assays of KLK mRNAs are highly concordant with CellSearch CTC results in patients with CRPC. KLK2/3-expressing CTCs are common in men with CRPC and bone metastases but are rare in patients with metastases diagnosed only in soft tissues and patients with localized cancer.

A Molecular Signature Predictive of Indolent Prostate Cancer

A three-gene panel derived from mechanistic models of cell senescence predicts outcome of low Gleason score prostate tumors. To Treat or Not to Treat...* ...That is often the question for prostate cancer patients and their caretakers. Now, Irshad et al. describe a gene signature that may guide treatment choices when prognosis is unclear. Along with other clinical and molecular parameters, pathologists use the Gleason grading system to stage prostate cancers and predict patient prognosis. A Gleason score is assigned to a cancer on the basis of its microscopic features and is directly related to tumor aggressiveness and poor prognosis. Most newly diagnosed prostate cancers with low Gleason scores require no treatment intervention and are monitored with active surveillance (indolent tumors). However, the pinpointing of tumors that are aggressive and lethal despite having low Gleason scores is a clinical challenge. In these cases, new tools are needed to answer the title question. Irshad and colleagues show that low Gleason score prostate tumors can be separated into distinct indolent and aggressive subgroups on the basis of their expression of aging and senescence genes. Using patient tissue samples and gene expression data along with computational biology techniques, including a decision tree learning model, the authors identified three genes—FGFR1, PMP22, and CDKN1A—that predicted the clinical outcome of low Gleason score prostate tumors. The prognostic power of the three-gene signature was validated in independent patient cohorts, and expression of the FGFR1, PMP22, and CDKN1A proteins in biopsy samples identified Gleason 6 patients who had failed surveillance over a 10-year period. Just as Hamlet laments in his famous soliloquy, oncologists and patients need more information about the unknown before making a decision. The new signature might aid in the choice between “bear[ing] those ills [they] have” with active surveillance or actively treating—and hopefully thwarting—aggressive tumors. *Paraphrased from the “To be, or not to be” soliloquy in Hamlet by William Shakespeare. Many newly diagnosed prostate cancers present as low Gleason score tumors that require no treatment intervention. Distinguishing the many indolent tumors from the minority of lethal ones remains a major clinical challenge. We now show that low Gleason score prostate tumors can be distinguished as indolent and aggressive subgroups on the basis of their expression of genes associated with aging and senescence. Using gene set enrichment analysis, we identified a 19-gene signature enriched in indolent prostate tumors. We then further classified this signature with a decision tree learning model to identify three genes—FGFR1, PMP22, and CDKN1A—that together accurately predicted outcome of low Gleason score tumors. Validation of this three-gene panel on independent cohorts confirmed its independent prognostic value as well as its ability to improve prognosis with currently used clinical nomograms. Furthermore, protein expression of this three-gene panel in biopsy samples distinguished Gleason 6 patients who failed surveillance over a 10-year period. We propose that this signature may be incorporated into prognostic assays for monitoring patients on active surveillance to facilitate appropriate courses of treatment.

Salvage Cryosurgery of the Prostate for Failure After Primary Radiotherapy or Cryosurgery: Long-term Clinical, Functional, and Oncologic Outcomes in a Large Cohort at a Tertiary Referral Centre

BACKGROUND Salvage cryosurgery (SC) is a recognised option for patients who fail either primary radiation or cryosurgery. OBJECTIVE To report outcomes of patients undergoing SC. DESIGN, SETTING, AND PARTICIPANTS A consecutive series of 396 patients who had failed either primary radiotherapy or cryosurgery underwent SC between October 1994 and August 2011. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Demographic and clinical parameters before primary and salvage treatment were evaluated; disease-free-survival (DFS), overall-survival (OS), disease-specific-survival (DSS), and complications were assessed. RESULTS AND LIMITATIONS Sufficient follow-up data were available for 328 patients. Median age was 65.8 yr (range: 45-81 yr), median serum prostate-specific antigen (PSA) level was 8.0 ng/ml (range: 0.6-290.0 ng/ml). After primary treatment, median time to recurrence was 55 mo (range: 0.0-183.6 mo). SC was performed at a median of 67.5 mo (range: 7.0-212.7 mo) later; median pre-SC PSA level was 4.0 ng/ml (range: 0.1-112.4 ng/ml). Median PSA nadir was 0.2 ng/ml (range: 0.01-70.70 ng/ml), reached after a median of 2.6 mo (range: 2.0-67.3 mo) after SC. Median follow-up was 47.8 mo (range: 1.6-203.5 mo). Respective 5- and 10-yr DFS was 63% and 35%; OS: 74% and 45%; and DSS: 91% and 79%. In univariate analyses, time from primary treatment to SC or recurrence, PSA level before SC, and PSA nadir after SC were all significant predictors of recurrence (p ≤ 0.01). PSA before SC and time to recurrence were also predictive of DSS (p=0.003 and p=0.01, respectively). In multivariate analyses, only PSA nadir after SC was predictive of recurrence and DSS (p<0.001 and p=0.012, respectively). Complications were rare (range: 0.6-4.6%). Fifty-five patients (16.7%) underwent focal SC. Median PSA nadir after focal SC was 0.44 ng/ml (range: 0.04-20.1 ng/ml). Twenty-seven patients (49%) experienced recurrence. Respective 5- and 10-yr DFS was 47% and 42%; OS: 87% and 81%; and DSS: 100% and 83%. CONCLUSIONS Our analysis confirms SC as an effective treatment option for patients failing primary therapy. Patients experienced excellent survival outcome and minimal associated morbidity after SC. Focal SC is an efficacious treatment for properly selected patients.

Evaluation of molecular forms of prostate-specific antigen and human kallikrein 2 in predicting biochemical failure after radical prostatectomy.

Most pretreatment risk‐assessment models to predict biochemical recurrence (BCR) after radical prostatectomy (RP) for prostate cancer rely on total prostate‐specific antigen (PSA), clinical stage, and biopsy Gleason grade. We investigated whether free PSA (fPSA) and human glandular kallikrein‐2 (hK2) would enhance the predictive accuracy of this standard model. Preoperative serum samples and complete clinical data were available for 1,356 patients who underwent RP for localized prostate cancer from 1993 to 2005. A case‐control design was used, and conditional logistic regression models were used to evaluate the association between preoperative predictors and BCR after RP. We constructed multivariable models with fPSA and hK2 as additional preoperative predictors to the base model. Predictive accuracy was assessed with the area under the ROC curve (AUC). There were 146 BCR cases; the median follow up for patients without BCR was 3.2 years. Overall, 436 controls were matched to 146 BCR cases. The AUC of the base model was 0.786 in the entire cohort; adding fPSA and hK2 to this model enhanced the AUC to 0.798 (p = 0.053), an effect largely driven by fPSA. In the subgroup of men with total PSA ≤10 ng/ml (48% of cases), adding fPSA and hK2 enhanced the AUC of the base model to a similar degree (from 0.720 to 0.726, p = 0.2). fPSA is routinely measured during prostate cancer detection. We suggest that the role of fPSA in aiding preoperative prediction should be investigated in further cohorts.

Efficacy and Safety of Blue Light Flexible Cystoscopy with Hexaminolevulinate in the Surveillance of Bladder Cancer: A Phase III, Comparative, Multicenter Study

Purpose: We compared blue light flexible cystoscopy with white light flexible cystoscopy for the detection of bladder cancer during surveillance. Materials and Methods: Patients at high risk for recurrence received hexaminolevulinate intravesically before white light flexible cystoscopy and randomization to blue light flexible cystoscopy. All suspicious lesions were documented. Patients with suspicious lesions were referred to the operating room for repeat white and blue light cystoscopy. All suspected lesions were biopsied or resected and specimens were examined by an independent pathology consensus panel. The primary study end point was the proportion of patients with histologically confirmed malignancy detected only with blue light flexible cystoscopy. Additional end points were the false‐positive rate, carcinoma in situ detection and additional tumors detected only with blue light cystoscopy. Results: Following surveillance 103 of the 304 patients were referred, including 63 with confirmed malignancy, of whom 26 had carcinoma in situ. In 13 of the 63 patients (20.6%, 95% CI 11.5–32.7) recurrence was seen only with blue light flexible cystoscopy (p <0.0001). Five of these cases were confirmed as carcinoma in situ. Operating room examination confirmed carcinoma in situ in 26 of 63 patients (41%), which was detected only with blue light cystoscopy in 9 of the 26 (34.6%, 95% CI 17.2–55.7, p <0.0001). Blue light cystoscopy identified additional malignant lesions in 29 of the 63 patients (46%). The false‐positive rate was 9.1% for white and blue light cystoscopy. None of the 12 adverse events during surveillance were serious. Conclusions: Office based blue light flexible cystoscopy significantly improves the detection of patients with recurrent bladder cancer and it is safe when used for surveillance. Blue light cystoscopy in the operating room significantly improves the detection of carcinoma in situ and detects lesions that are missed with white light cystoscopy.

Predictors of biochemical recurrence after primary focal cryosurgery (hemiablation) for localized prostate cancer: A multi-institutional analytic comparison of Phoenix and Stuttgart criteria

BACKGROUND The Phoenix definition (PD) and Stuttgart definition (SD) designed to determine biochemical recurrence (BCR) in patients with postradiotherapy and high-intensity focused ultrasound organ-confined prostate cancer are being applied to follow patients after cryosurgery. We sought to identify predictors of BCR using the PD and SD criteria in patients who underwent primary focal cryosurgery (PFC). MATERIALS AND METHODS We performed a retrospective review of patients who underwent PFC (hemiablation) at 2 referral centers from 2000 to 2014. Patients were followed up with serial prostate-specific antigen (PSA). PSA levels, pre- and post-PFC biopsy, Gleason scores, number of positive cores, and BCR (PD = [PSA nadir+2ng/ml]; SD = [PSA nadir+1.2ng/ml]) were recorded. Patients who experienced BCR were biopsied, monitored carefully or treated at the discretion of the treating urologist. Cox regression and survival analyses were performed to assess time to BCR using PD and SD. RESULTS A total of 163 patients were included with a median follow-up of 36.6 (interquartile range: 18.9-56.4) months. In all, 64 (39.5%) and 98 (60.5%) experienced BCR based on PD and SD, respectively. On multivariable Cox regression, the number of positive pre-PFC biopsy cores was an independent predictor of both PD (hazard ratio [HR] = 1.4, P = 0.001) and SD (HR = 1.3, P = 0.006) BCRs. Post-PFC PSA nadir was an independent predictor of BCR using the PD (HR = 2.2, P = 0.024) but not SD (HR = 1.4, P = 0.181). Survival analysis demonstrated a 3-year BCR-free survival rate of 56% and 36% for PD and SD, respectively. Of those biopsied after BCR, 14/26 (53.8%) using the PD and 18/35 (51.4%) using the SD were found to have residual/recurrent cancer. Of those with prostate cancer on post-PFC biopsy, 57.1% of those with BCR by the PD and 66.7% of those with BCR by the SD were found to have a Gleason score ≥7. CONCLUSION Both the PD and the SD may be used to determine BCR in post-PFC patients. However, the ideal definition of BCR after PFC remains to be elucidated.

Timing and Predictors of Early Urologic and Infectious Complications After Renal Transplant: An Analysis of a New York Statewide Database

OBJECTIVES The most common complications after renal transplant are urologic and are a cause of significant morbidity in a vulnerable population. We sought to characterize the timing and predictors of urologic complications after renal transplant using a statewide database. MATERIALS AND METHODS We queried the New York Statewide Planning and Research Cooperative System database to identify patients who underwent renal transplant from 2005 to 2013. Postoperative complications included hydronephrosis, ureteral stricture, vesicoureteral reflux, nephrolithiasis, and urinary tract infections. Cox proportional hazards model was used to assess independent predictors of urologic complications. RESULTS In total, 9038 patients were included in the analyses. Urologic complications occurred in 11.3% of patients and included hydronephrosis (12.0%), nephrolithiasis (2.8%), ureteral stricture (2.4%), and vesicoureteral reflux (1.5%). We found that 23% experienced at least one urinary tract infection. On multivariate analysis, predictors of urologic complications included medicare insurance, hypertension, and prior urinary tract infection. Graft recipients from living donors were less likely to experience urologic complications than deceased-donor kidney recipients (P < .001). CONCLUSIONS Urologic complications occur in a significant proportion of renal transplants. Further study is needed to identify risk factors for complications after renal transplantation to decrease morbidity in this vulnerable population.

Outcomes and Prognostic Factors of Primary Urethral Cancer

OBJECTIVE To identify prognostic and treatment factors for primary urethral cancer using a nationwide database. MATERIALS AND METHODS The National Cancer Database was queried for all cases of primary urethral cancer from 2004 to 2013. Patients with other cancer diagnoses, metastasis, or diagnosis on autopsy were excluded. Proportional hazards regression was used to identify independent predictors of overall survival in patients with primary urethral cancer. Because we hypothesized that predictors may covary by sex, we also performed regression analysis stratified by sex. RESULTS We identified 1268 men and 869 women with primary urethral cancer. Women tended to have more advanced tumors and adenocarcinoma histology. Median survival for the entire cohort was 49 months (43-55), with 5- and 10-year survival rates of 46% and 31%, respectively. On multivariate analysis, age, race, stage, grade, and Charlson comorbidity index were independent predictors of overall survival. Histology was not a predictor of overall survival in the combined model; however, adenocarcinoma in women increased hazards of death, whereas it decreased hazards of death in men when compared with squamous cell carcinoma. CONCLUSION Men and women with primary urethral cancer had significant differences in histology, grade, and nodal status. In addition to several expected disease-related factors, black race was associated with increased mortality for patients with primary urethral cancer.

Collecting duct carcinoma of the kidney: Disease characteristics and treatment outcomes from the National Cancer Database

OBJECTIVE To use a large population-level database to assess survival outcomes for collecting duct renal cell carcinoma (CDRCC). MATERIALS AND METHODS The National Cancer Database was queried for all cases of CDRCC and clear cell renal cell carcinoma (CCRCC) from 2004 to 2013. After removing patients with other cancer diagnoses, the analytic cohort was composed of 201,686 CCRCC and 577 CDRCC cases. Kaplan-Meier and cox proportional hazards analysis were employed to model survival. RESULTS Compared to CCRCC, patients with CDRCC presented with higher grade and stage, node positive, and metastatic disease (70.7% vs. 30.0% with metastasis; P<0.001). Overall median survival for CDRCC was 13.2 months (95% CI: 11.0-15.5) compared to the 122.5 months (95% CI: 121.0-123.9) for CCRCC. On multivariate analysis of the CDRCC cohort, increasing T stage, high-grade disease, and metastasis were predictors of mortality. Of 184 patients with metastatic CDRCC, 113 underwent cytoreductive nephrectomy (CNx) whereas the rest were treated with chemo/radiation or observed. Survival outcomes were improved in patients who received both CNx with chemo/radiation compared to CNx alone (hazard ratio = 0.51, 95% CI: 0.32-0.79) or chemo/radiation alone (hazard ratio = 0.57, 95% CI: 0.37-0.89) on multivariate analysis. CONCLUSION CDRCC is an aggressive subtype of renal cell carcinoma. Median survival is 13 months after diagnosis, drastically lower than for CCRCC. More than 70% of patients have metastatic disease at diagnosis. Chemo/radiation in addition to CNx is associated with a survival benefit over single mode therapy.