Bastian Keck

MicroRNA profiles of prostate carcinoma detected by multiplatform microRNA screening.

MicroRNAs (miRNAs) are small RNA molecules that regulate gene expression via posttranscriptional inhibition of protein synthesis. They play a vital role in tumorigenesis. To characterize the diagnostic potential of miRNAs in prostate cancer, a leading cause of cancer mortality, we performed screening of miRNA expression profiles. We used commercially available microarrays to establish miRNA expression profiles from a cohort of 20 cancer samples. The expression of selected miRNAs was analyzed by quantitative real‐time PCR and the identity of miRNA expressing cells was determined by miRNA in situ hybridization. We identified 25 miRNAs that showed a significant differential expression in cancer samples. The comparison with previously published data generated by deep sequencing of cDNA libraries of small RNA molecules revealed a concordance rate of 47% among miRNAs identified with both techniques. The differential expression of miRNAs miR‐375, miR‐143 and miR‐145 was validated by quantitative PCR. MiRNA in situ hybridization revealed that the differential expression is cancer‐cell associated. A combination of three miRNAs correctly classified tissue samples with an accuracy of 77.6% with an area under the receiver–operator characteristic curve of 0.810. Our data extend the knowledge about the deregulation of miRNAs in prostate cancer. The differential expression of several miRNAs is highly consistent using independent cohorts of tumor samples, different tissue preservation methods and different experimental methods. Our results indicate that combinations of miRNAs are promising biomarkers for the diagnosis of prostate cancer.

Comprehensive Transcriptional Analysis of Early-Stage Urothelial Carcinoma

Non-muscle-invasive bladder cancer (NMIBC) is a heterogeneous disease with widely different outcomes. We performed a comprehensive transcriptional analysis of 460 early-stage urothelial carcinomas and showed that NMIBC can be subgrouped into three major classes with basal- and luminal-like characteristics and different clinical outcomes. Large differences in biological processes such as the cell cycle, epithelial-mesenchymal transition, and differentiation were observed. Analysis of transcript variants revealed frequent mutations in genes encoding proteins involved in chromatin organization and cytoskeletal functions. Furthermore, mutations in well-known cancer driver genes (e.g., TP53 and ERBB2) were primarily found in high-risk tumors, together with APOBEC-related mutational signatures. The identification of subclasses in NMIBC may offer better prognostication and treatment selection based on subclass assignment.

Cabazitaxel Plus Prednisone for Metastatic Castration-resistant Prostate Cancer Progressing After Docetaxel: Results from the German Compassionate-use Programme

BACKGROUND Cabazitaxel (Cbz) is an approved second-line treatment in metastatic castration-resistant prostate cancer (mCRPC) following docetaxel therapy with a significant survival benefit compared with mitoxantrone. However, grade 3/4 toxicities were reported in 82% of patients. OBJECTIVE To report on the safety results of mCRPC patients treated within a compassionate-use programme in Germany. DESIGN, SETTING, AND PARTICIPANTS A total of 111 patients with a mean age of 67.9 yr (range: 49-81 yr) and progressive mCRPC were included. Patients had received a mean number of 12.7 ± 10.8 cycles (range: 6-69 cycles) of docetaxel with a mean cumulative dose of 970.9 mg/m(2); mean time from last docetaxel application to progression was 6.95 mo (range: 2-54 mo). Of the patients, 31.5% progressed by prostate-specific antigen (PSA) increase only; the remainder had a combination of PSA increase and clinical progression. INTERVENTION Cbz at a dosage of 25mg/m(2) intravenously every 3 wk combined with 5mg of oral prednisone twice a day. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Treatment-associated toxicity was the primary study end point; progression-free and overall survival were secondary end points. A descriptive statistical analysis was performed. RESULTS AND LIMITATIONS Patients received a mean number of 6.5 ± 2.2 cycles of Cbz and a mean cumulative dose of 160.3 ± 51.5mg/m(2). Grade 3 and 4 treatment-emergent adverse events were recorded in 34 patients (30.6%) and 18 patients (16.2%), respectively. Grade 3/4 anaemia, neutropenia, and thrombocytopenia were reported in 4.5%, 7.2%, and 0.9% of the patients, respectively. Neutropenic fever was reported in 1.8% of the patients. Grade 3/4 gastrointestinal toxicity was identified in 4.5% of the patients. Three patients died because of Cbz-related toxicity. Granulocyte colony-stimulating growth factors were used in 17.1% of patients. The limitations are due to the nonrandomised nature of the trial. CONCLUSIONS Treatment with Cbz is tolerable and is associated with a low incidence of serious adverse events in a real-world patient population with CRPC. The outcome of serious adverse events can be minimised with proactive treatment management and conscientious monitoring.

The plasmacytoid carcinoma of the bladder--rare variant of aggressive urothelial carcinoma.

The WHO 2004 classification defines new histological and molecular variants of urothelial carcinoma. However, there are limited data available on the clinicopathological characteristics or prognosis of these variants. We present histopathological, molecular and clinical data of 32 plasmacytoid carcinomas of the bladder (PUC) showing that PUC is a high‐grade tumor with molecular features of aggressive urothelial carcinoma, usually diagnosed in advanced pathological stage (64% pT3, 23% pT4) showing metastases in 60% of the patients. Average survival of our cohort of PUC treated with radical cystectomy and adjuvant chemotherapy was lower than what is typically seen for comparable conventional urothelial carcinomas. Eighty‐seven percent of the PUCs showed a negative or strongly reduced membranous staining of E‐cadherin. β‐Catenin staining was negative in 22.5%, and 16.7% of the remaining tumors showed nuclear accumulation. Aberrant CK20 expression (negative or >10% of cells stained) and negative CK7 staining was found in 100% and 22.6%, respectively. Ninety‐seven percent revealed positive staining for PAN‐CK. CD138 was positive in 78%, whereas MUM‐1 expression was negative in all cases. Multitarget fluorescence in situ hybridization showed all PUCs to be highly aneuploid and polysomic. Deletions on chromosome 9p21 seem to play an important role in this variant. FGFR3 and PIK3CA mutation analyses yielded no mutations in any of the PUCs analyzed. TP53 mutation analysis showed mutations in 29%. In summary, PUC is an aggressive variant of bladder cancer with molecular features of advanced bladder cancer and evidence of WNT pathway activation in some of the cases.

Identification of ZNF217, hnRNP-K, VEGF-A and IPO7 as targets for microRNAs that are downregulated in prostate carcinoma.

In primary prostate cancer (PCa), a major cause of cancer‐related death in men, the expression of various microRNAs (miRNAs) is deregulated. We previously detected several miRNAs, for example, miR‐24 and miR‐22, as significantly downregulated in PCa (Szczyrba et al., Mol Cancer Res 2010;8:529‐38). An in silico search predicted that zinc finger protein 217 (ZNF217) and importin 7 (IPO7) were potential target genes of these miRNAs. Additionally, for two genes that are deregulated in PCa (heterogeneous nuclear ribonucleoprotein K, hnRNP‐K, and vascular endothelial growth factor A, VEGF‐A), we identified two regulatory miRNAs, miR‐205 and miR‐29b. The regulation of the 3′‐untranslated regions of the four genes by their respective miRNAs was confirmed by luciferase assays. As expected, the upregulation of ZNF217, hnRNP‐K, VEGF‐A and IPO7 could be verified at the protein level in the PCa cell lines LNCaP and DU145. ZNF217 and IPO7, which had not yet been studied in PCa, were analyzed in more detail. ZNF217 mRNA is overexpressed in primary PCa samples, and this overexpression translates to an elevated protein level. However, IPO7 was upregulated at the protein level alone. The inhibition of ZNF217 and IPO7 by siRNA resulted in reduced proliferation of the PCa cell lines. ZNF217 could thus be identified as an oncogene that is overexpressed in PCa and affects the growth of PCa cell lines, whereas the function of IPO7 remains to be elucidated in greater detail.

Plasmacytoid variant of bladder cancer defines patients with poor prognosis if treated with cystectomy and adjuvant cisplatin-based chemotherapy

BackgroundSince the definition of different histologic subtypes of urothelial carcinomas by the World Health Organization (WHO) 2004 classification, description of molecular features and clinical behavior of these variants has gained more attention.MethodsWe reviewed 205 tumor samples of patients with locally advanced bladder cancer mainly treated within the randomized AUO-AB05/95 trial with radical cystectomy and adjuvant cisplatin-based chemotherapy for histologic subtypes. 178 UC, 18 plasmacytoid (PUC) and 9 micropapillary (MPC) carcinomas of the bladder were identified. Kaplan Meier analysis and backward multivariate Cox’s proportional hazards regression analysis were performed to compare overall survival between the three histologic subtypes.ResultsPatients suffering from PUC have the worst clinical outcome regarding overall survival compared to conventional UC and MPC of the bladder that in turn seem have to best clinical outcome (27.4 months, 62.6 months, and 64.2 months, respectively; p=0.013 by Kaplan Meier analysis). Backward multivariate Cox´s proportional hazards regression analysis (adjusted to relevant clinicopathological parameters) showed a hazard ratio of 3.2 (p=0.045) for PUC in contrast to patients suffering from MPC.ConclusionsHistopathological diagnosis of rare variants of urothelial carcinoma can identify patients with poor prognosis.

Do urology journals enforce trial registration? A cross-sectional study of published trials.

Objectives (1) To assess endorsement of trial registration in author instructions of urology-related journals and (2) to assess whether randomised controlled trials (RCTs) in the field of urology were effectively registered. Design Cross-sectional study of author instructions and published trials. Setting Journals publishing in the field of urology. Participants First, the authors analysed author instructions of 55 urology-related journals indexed in ‘Journal Citation Reports 2009’ (12/2010). The authors divided these journals in two groups: those requiring and those not mentioning trial registration as a precondition for publication. Second, the authors chose the five journals with the highest impact factor (IF) from each group. Intervention MEDLINE search to identify RCTs published in these 10 journals in 2009 (01/2011); search of the clinical trials meta-search interface of WHO (International Clinical Trials Registry Platform) for RCTs that lacked information about registration (01–03/2011). Two authors independently assessed the information. Outcome measures Proportion of journals providing advice about trial registration and proportion of trials registered. Results Of 55 journals analysed, 26 (47.3%) provided some editorial advice about trial registration. Journals with higher IFs were more likely to mention trial registration explicitly (p=0.015). Of 106 RCTs published in 2009, 63 were registered (59.4%) with a tendency to an increase after 2005 (83.3%, p=0.035). 71.4% (30/42) of the RCTs that were published in journals mentioning and requiring registration, and 51.6% (33/64) of the RCTs that were published in journals that did not mention trial registration explicitly were registered. This difference was statistically significant (p=0.04). Conclusions The existence of a statement about trial registration in author instructions resulted in a higher proportion of registered RCTs in those journals. Journals with higher IFs were more likely to mention trial registration.

Tamoxifen for the management of breast events induced by non-steroidal antiandrogens in patients with prostate cancer: a systematic review

BackgroundTamoxifen has emerged as a potential management option for gynecomastia and breast pain due to non-steroidal antiandrogens, and it is considered an alternative to surgery or radiotherapy. The objective of this systematic review was to assess the benefits and harms of tamoxifen, in comparison to other treatment options, for either the prophylaxis or treatment of breast events induced by non-steroidal antiandrogens in prostate cancer patients.MethodsWe searched CENTRAL, MEDLINE, EMBASE, reference lists, the abstracts of three major conferences and three trial registers to identify ongoing randomized controlled trials (RCTs). Two authors independently screened the articles identified, assessed the trial quality and extracted data. The protocol was prospectively registered (CRD42011001320; http://www.crd.york.ac.uk/PROSPERO).ResultsFour studies were identified. Tamoxifen significantly reduced the risk of suffering from gynecomastia (risk ratio 9RR0 0.10, 95% CI 0.05 to 0.22) or breast pain (RR 0.06, 95% CI 0.02 to 0.17) at six months compared to untreated controls. Tamoxifen also showed a significant benefit for the prevention of gynecomastia (RR 0.22, 95% CI 0.08 to 0.58) and breast pain (RR 0.25, 95% CI 0.10 to 0.64) when compared to anastrozole after a median of 12 months. One study showed a significant benefit of tamoxifen for the prevention of gynecomastia (RR 0.24, 95% CI 0.09 to 0.65) and breast pain (RR 0.20, 95% CI 0.06 to 0.65) when compared with radiotherapy at six months. Radiotherapy increased the risk of suffering from nipple erythema and skin irritation, but there were no significant differences for any other adverse events (all P > 0.05).ConclusionsThe currently available evidence suggests good efficacy of tamoxifen for the prevention and treatment of breast events induced by non-steroidal antiandrogens. The impact of tamoxifen therapy on long-term adverse events, disease progression and survival remains unclear. Further large, well-designed RCTs, including long-term follow-ups, are warranted. Also, the optimal dose needs to be clarified.

Neuropilin‐2 and its ligand VEGF‐C predict treatment response after transurethral resection and radiochemotherapy in bladder cancer patients

The standard treatment for invasive bladder cancer is radical cystectomy. In selected patients, bladder‐sparing therapy can be performed by transurethral resection (TURBT) and radio‐chemotherapy (RCT) or radiotherapy (RT). Our published in vitro data suggest that the Neuropilin‐2 (NRP2)/VEGF‐C axis plays a role in therapy resistance. Therefore, we studied the prognostic impact of NRP2 and VEGF‐C in 247 bladder cancer patients (cN0M0) treated with TURBT and RCT (n = 198) or RT (n = 49) and a follow‐up time up to 15 years. A tissue microarray was analyzed by immunohistochemistry. NRP2 expression emerged as a prognostic factor in overall survival (OS; HR: 3.42; 95% CI: 1.48 – 7.86; p = 0.004) and was associated with a 3.85‐fold increased risk of an early cancer specific death (95% CI: 0.91 – 16.24; p = 0.066) in multivariate analyses. Cancer specific survival (CSS) dropped from 166 months to 85 months when NRP2 was highly expressed (p = 0.037). Patients with high VEGF‐C expression have a 2.29‐fold increased risk of shorter CSS (95% CI: 1.03–5.35; p = 0.043) in univariate analysis. CSS dropped from 170 months to 88 months in the case of high VEGF‐C expression (p = 0.041). Additionally, NRP2 and VEGF‐C coexpression is a prognostic marker for OS in multivariate models (HR: 7.54; 95% CI: 1.57–36.23; p = 0.012). Stratification for muscle invasiveness (T1 vs. T2‐T4) confirmed the prognostic role of NRP2 and NRP2/VEGF‐C co‐expression in patients with T2‐T4 but also with high risk T1 disease. In conclusion, immunohistochemistry for NRP2 and VEGF‐C has been determined to predict therapy outcome in bladder cancer patients prior to TURBT and RCT.

Rhabdoid and Undifferentiated Phenotype in Renal Cell Carcinoma: Analysis of 32 Cases Indicating a Distinctive Common Pathway of Dedifferentiation Frequently Associated With SWI/SNF Complex Deficiency.

Undifferentiated (anaplastic) and rhabdoid cell features are increasingly recognized as adverse prognostic findings in renal cell carcinoma (RCC), but their molecular pathogenesis has not been studied sufficiently. Recent studies identified alterations in the Switch Sucrose nonfermentable (SWI/SNF) chromatin remodeling complex as molecular mechanisms underlying dedifferentiation and rhabdoid features in carcinomas of different organs. We herein have analyzed 32 undifferentiated RCCs having in common an undifferentiated (anaplastic) phenotype, prominent rhabdoid features, or both, irrespective of the presence or absence of conventional RCC component. Cases were stained with 6 SWI/SNF pathway members (SMARCB1, SMARCA2, SMARCA4, ARID1A, SMARCC1, and SMARCC2) in addition to conventional RCC markers. Patients were 20 males and 12 females aged 32 to 85 years (mean, 59). A total of 22/27 patients with known stage presented with ≥pT3. A differentiated component varying from microscopic to major component was detected in 20/32 cases (16 clear cell and 2 cases each chromophobe and papillary RCC). The undifferentiated component varied from rhabdoid dyscohesive cells to large epithelioid to small monotonous anaplastic cells. Variable loss of at least 1 SWI/SNF complex subunit was noted in the undifferentiated/rhabdoid component of 21/32 cases (65%) compared with intact or reduced expression in the differentiated component. A total of 15/17 patients (88%) with follow-up died of metastatic disease (mostly within 1 y). Only 2 patients were disease free at last follow-up (1 and 6 y). No difference in survival, age distribution, or sex was observed between the SWI/SNF-deficient and the SWI/SNF-intact group. This is the first study exploring the role of SWI/SNF deficiency as a potential mechanism underlying undifferentiated and rhabdoid phenotype in RCC. Our results highlight the association between the aggressive rhabdoid phenotype and the SWI/SNF complex deficiency, consistent with studies on similar neoplasms in other organs. Thorough sampling of such tumors that are usually huge and locally advanced is necessary for recognizing the clone of origin and hence for proper subtyping and also for differentiating them from undifferentiated urothelial carcinoma.