Stefan C. Müller

Positive Surgical Margin Appears to Have Negligible Impact on Survival of Renal Cell Carcinomas Treated by Nephron-Sparing Surgery

BACKGROUNDnThe occurrence of positive surgical margins (PSMs) after partial nephrectomy (PN) is rare, and little is known about their natural history.nnnOBJECTIVEnTo identify predictive factors of cancer recurrence and related death in patients having a PSM following PN.nnnDESIGN, SETTING, AND PARTICIPANTSnSome 111 patients with a PSM were identified from a multicentre retrospective survey and were compared with 664 negative surgical margin (NSM) patients. A second cohort of NSM patients was created by matching NSM to PSM for indication, tumour size, and tumour grade.nnnMEASUREMENTSnPSM and NSM patients were compared using student t tests and chi-square tests on independent samples. A Cox proportional hazards regression model was used to test the independent effects of clinical and pathologic variables on survival.nnnRESULTS AND LIMITATIONSnMean age at diagnosis was 61+/-12.5 yr. Mean tumour size was 3.5+/-2 cm. Imperative indications accounted for 39% (43 of 111) of the cases. Some 18 patients (16%) underwent a second surgery (partial or total nephrectomy). With a mean follow-up of 37 mo, 11 patients (10%) had recurrences and 12 patients (11%) died, including 6 patients (5.4%) who died of cancer progression. Some 91% (10 of 11) of the patients who had recurrences and 83% of the patients (10 of 12) who died belonged to the group with imperative surgical indications. Rates of recurrence-free survival, of cancer-specific survival, and of overall survival were the same among NSM patients and PSM patients. The multivariable Cox model showed that the two variables that could predict recurrence were the indication (p=0.017) and tumour location (p=0.02). No other variable, including PSM status, had any effect on recurrence. None of the studied parameters had any effect on the rate of cancer-specific survival.nnnCONCLUSIONSnPSM status occurs more frequently in cases in which surgery is imperative and is associated with an increased risk of recurrence, but PSM status does not appear to influence cancer-specific survival. Additional follow-up is needed.

Global histone acetylation levels: Prognostic relevance in patients with renal cell carcinoma

Epigenetic alterations play an important role in carcinogenesis. Recent studies have suggested that global histone modifications are predictors of cancer recurrence in various tumor entities. Global histone acetylation levels (histone H3 lysine 9 acetylation [H3K9Ac], histone H3 lysine 18 acetylation [H3K18Ac], total histone H3 acetylation [H3Ac] and total histone H4 acetylation [H4Ac]) were determined in patients with renal cell carcinoma (RCC) using immunohistochemistry in a tissue micro array with 193 RCC and 10 oncocytoma specimens. The histone acetylation pattern was not different among the diverse histological subtypes of RCC or oncocytoma samples. The H3Ac levels were inversely correlated with pT‐stage (Pu2003=u20030.005), distant metastasis (Pu2003=u20030.036), Fuhrman grading (Pu2003=u20030.001) and RCC progression (Pu2003=u20030.029, hazard ratio 0.87). H4Ac deacetylation was correlated with pT‐stage (Pu2003=u20030.011) and grading (Pu2003=u20030.029). H3K18Ac levels were an independent predictor of cancer‐progression following surgery for localized RCC in the univariate (Pu2003=u20030.001, hazard ratio 0.78) and multivariate (Pu2003=u20030.005, hazard ratio 0.82) analysis. In conclusion, our study supports the concept of global histone modification levels as a universal cancer prognosis marker, and provides evidence for the use of histone deacetylases inhibitors as future drugs in the therapy of RCC. (Cancer Sci 2010; 101: 2664–2669)

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

BACKGROUNDnCabazitaxel (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.nnnOBJECTIVEnTo report on the safety results of mCRPC patients treated within a compassionate-use programme in Germany.nnnDESIGN, SETTING, AND PARTICIPANTSnA 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.nnnINTERVENTIONnCbz at a dosage of 25mg/m(2) intravenously every 3 wk combined with 5mg of oral prednisone twice a day.nnnOUTCOME MEASUREMENTS AND STATISTICAL ANALYSISnTreatment-associated toxicity was the primary study end point; progression-free and overall survival were secondary end points. A descriptive statistical analysis was performed.nnnRESULTS AND LIMITATIONSnPatients 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.nnnCONCLUSIONSnTreatment 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 Immune Checkpoint Regulator PD-L1 Is Highly Expressed in Aggressive Primary Prostate Cancer

Purpose: Therapies targeting the programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) pathway promote anti-tumor immunity and have shown promising results in various tumors. Preliminary data further indicate that immunohistochemically detected PD-L1 may be predictive for anti-PD-1 therapy. So far, no data are available on PD-L1 expression in primary prostate cancer. Experimental Design: Following validation of a monoclonal antibody, immunohistochemical analysis of PD-L1 expression was performed in two independent, well-characterized cohorts of primary prostate cancer patients following radical prostatectomy (RP), and resulting data were correlated to clinicopathological parameters and outcome. Results: In the training cohort (n = 209), 52.2% of cases expressed moderate to high PD-L1 levels, which positively correlated with proliferation (Ki-67, P < 0.001), Gleason score (P = 0.004), and androgen receptor (AR) expression (P < 0.001). Furthermore, PD-L1 positivity was prognostic for biochemical recurrence [BCR; P = 0.004; HR, 2.37; 95% confidence interval (CI), 1.32–4.25]. In the test cohort (n = 611), moderate to high PD-L1 expression was detected in 61.7% and remained prognostic for BCR in univariate Cox analysis (P = 0.011; HR, 1.49; 95% CI, 1.10–2.02). The correlation of Ki-67 and AR with PD-L1 expression was confirmed in the test cohort (P < 0.001). In multivariate Cox analysis of all patients, PD-L1 was corroborated as independently prognostic for BCR (P = 0.007; HR, 1.46; 95% CI, 1.11–1.92). Conclusions: We provide first evidence that expression of the therapy target PD-L1 is not only highly prevalent in primary prostate cancer cells but is also an independent indicator of BCR, suggesting a biologic relevance in primary tumors. Further studies need to ascertain if PD-1/PD-L1–targeted therapy might be a treatment option for hormone-naïve prostate cancers. Clin Cancer Res; 22(8); 1969–77. ©2015 AACR.

Identification of novel long non-coding RNAs in clear cell renal cell carcinoma

BackgroundLong non-coding RNAs (lncRNA) play an important role in carcinogenesis; knowledge on lncRNA expression in renal cell carcinoma is rudimental. As a basis for biomarker development, we aimed to explore the lncRNA expression profile in clear cell renal cell carcinoma (ccRCC) tissue.ResultsMicroarray experiments were performed to determine the expression of 32,183 lncRNA transcripts belonging to 17,512 lncRNAs in 15 corresponding normal and malignant renal tissues. Validation was performed using quantitative real-time PCR in 55 ccRCC and 52 normal renal specimens. Computational analysis was performed to determine lncRNA-microRNA (MiRTarget2) and lncRNA-protein (catRAPID omics) interactions. We identified 1,308 dysregulated transcripts (expression change >2-fold; upregulated: 568, downregulated: 740) in ccRCC tissue. Among these, aberrant expression was validated using PCR: lnc-BMP2-2 (mean expression change: 37-fold), lnc-CPN2-1 (13-fold), lnc-FZD1-2 (9-fold), lnc-ITPR2-3 (15-fold), lnc-SLC30A4-1 (15-fold), and lnc-SPAM1-6 (10-fold) were highly overexpressed in ccRCC, whereas lnc-ACACA-1 (135-fold), lnc-FOXG1-2 (19-fold), lnc-LCP2-2 (2-fold), lnc-RP3-368B9 (19-fold), and lnc-TTC34-3 (314-fold) were downregulated. There was no correlation between lncRNA expression with clinical-pathological parameters. Computational analyses revealed that these lncRNAs are involved in RNA-protein networks related to splicing, binding, transport, localization, and processing of RNA. Small interfering RNA (siRNA)-mediated knockdown of lnc-BMP2-2 and lnc-CPN2-1 did not influence cell proliferation.ConclusionsWe identified many novel lncRNA transcripts dysregulated in ccRCC which may be useful for novel diagnostic biomarkers.

Epigenetic biomarkers in the blood of patients with urological malignancies

In the era of personalized medicine, there is an urgent need for non-invasive biomarkers to optimize the individual treatment of cancer patients. Epigenetic alterations, including DNA methylation and non-coding RNAs, are a hallmark of malignant tumors. The detection of many of these epigenetic conditions is feasible in bodily fluids, that is, blood plasma and serum, and may therefore be used for liquid biopsy. In this review, we summarize and discuss the current state of research on circulating epigenetic alterations (DNA methylation, miRNA and long non-coding RNA) in serum and plasma of patients with bladder cancer, prostate cancer, renal cell carcinoma and testicular germ cell cancer.

Prostate Cancer Unit Initiative in Europe: A position paper by the European School of Oncology.

The Prostate Cancer Programme of the European School of Oncology developed the concept of specialised interdisciplinary and multiprofessional prostate cancer care to be formalized in Prostate Cancer Units (PCU). After the publication in 2011 of the collaborative article The Requirements of a Specialist Prostate Cancer Unit: A Discussion Paper from the European School of Oncology, in 2012 the PCU Initiative in Europe was launched. A multiprofessional Task Force of internationally recognized opinion leaders, among whom representatives of scientific societies, and patient advocates gathered to set standards for quality comprehensive prostate cancer care and designate care pathways in PCUs. The result was a consensus on 40 mandatory and recommended standards and items, covering several macro-areas, from general requirements to personnel to organization and case management. This position paper describes the relevant, feasible and applicable core criteria for defining PCUs in most European countries delivered by PCU Initiative in Europe Task Force.

Identification of novel differentially expressed lncRNA and mRNA transcripts in clear cell renal cell carcinoma by expression profiling.

Clear cell renal cell carcinoma (ccRCC) is a common human malignancy. Despite numerous efforts, there is still no reliable biomarker or combination of biomarkers available for daily practice. Our study was designed to explore the expression profile of messenger RNA (mRNA) and long non-coding RNA (lncRNA) transcripts in ccRCC in order to identify potential diagnostic biomarkers for patients with ccRCC. Total RNA from corresponding normal and malignant tissue of 15 patients with ccRCC was isolated. Expression profiling was performed using a custom Agilent gene expression microarray which allowed the analysis of 34,144 mRNA and 32,183 lncRNA transcripts. We observed that a subset of mRNA (n = 1064; 3.1%) and lncRNA (n = 1308; 4.1%) transcripts are dysregulated (fold change > 2) in ccRCC tissue. The relative higher number of differentially expressed lncRNAs indicates that lncRNA profiling may be better suited for diagnostic purposes; a number of so far unknown RNAs with potential diagnostic interest in ccRCC are identified by our gene expression profiling study. The data are deposited in the Gene Expression Omnibus (GSE61763).

Glutathione-S-transferase pi 1(GSTP1) gene silencing in prostate cancer cells is reversed by the histone deacetylase inhibitor depsipeptide

Gene silencing by epigenetic mechanisms is frequent in prostate cancer (PCA). The link between DNA hypermethylation and histone modifications is not completely understood. We chose the GSTP1 gene which is silenced by hypermethylation to analyze the effect of the histone deacetylase inhibitor depsipeptide on DNA methylation and histone modifications at the GSTP1 promoter site. Prostate cell lines (PC-3, LNCaP, and BPH-1) were treated with depsipeptide; apoptosis (FACS analysis), GSTP1 mRNA levels (quantitative real-time PCR), DNA hypermethylation (methylation-specific PCR), and histone modifications (chromatin immunoprecipitation) were studied. Depsipeptide induced apoptosis in PCA cells, but not a cell cycle arrest. Depispeptide reversed DNA hypermethylation and repressive histone modifications (reduction of H3K9me2/3 and H3K27me2/3; increase of H3K18Ac), thereby inducing GSTP1 mRNA re-expression. Successful therapy requires both, DNA demethylation and activating histone modifications, to induce complete gene expression of epigenetically silenced genes and depsipeptide fulfils both criteria.

Identification of the dopamine transporter SLC6A3 as a biomarker for patients with renal cell carcinoma

BackgroundClear cell renal cell carcinoma (ccRCC) is among the most common human malignancies.MethodsIn order to provide better understanding of the molecular biology of ccRCC and to identify potential diagnostic/prognostic biomarker and therapeutic targets, we utilized a microarray to profile mRNA expression of corresponding normal and malignant renal tissues. Real-time PCR, Western Blot and immunohistochemistry were applied to study the expression of candidate biomarkers. ccRCC cell lines were treated with sertraline to inhibit the dopamine transporter SLC6A3.ResultsDifferential expression of fourteen mRNAs, yet not studied in ccRCC in depth, was confirmed using qPCR (upregulation: SLC6A3, NPTX2, TNFAIP6, NDUFA4L2, ENPP3, FABP6, SPINK13; downregulation: FXYD4, SLC12A1, KNG1, NPHS2, SLC13A3, GCGR, PLG). Up-/downregulation was also confirmed for FXYD4, KNG1, NPTX2 and SLC12A1 by Western Blot on the protein level. In contrast to the mRNA expression, protein expression of the dopamine transporter SLC6A3 was lower in ccRCC compared to normal renal tissue. Immunohistochemistry indicated that this decrease was due to higher concentrations of SLC6A3 in the proximal tubules. Immunohistochemical analyses further demonstrated that high SLC6A3 expression in ccRCC tissue was correlated with a shorter period of recurrence-free survival following surgery. Treatment of ccRCC cells with the SLC6A3 inhibitor sertraline induced dose-dependent cell-death.ConclusionOur study identified several novel biomarkers with diagnostic potential and further investigations on sertraline as therapeutic agent in ccRCC patients are warranted.