Nivolumab + Ipilimumab as Immunotherapeutic Boost in Metastatic Urothelial Carcinoma: A Nonrandomized Clinical Trial

Importance

Studies with nivolumab, an approved therapy for metastatic urothelial carcinoma (mUC) after platinum-based chemotherapy, demonstrate improved outcomes with added high-dose ipilimumab.

Objective

To assess efficacy and safety of a tailored approach using nivolumab + ipilimumab as an immunotherapeutic boost for mUC.

Design, Setting, and Participants

In this phase 2 nonrandomized trial, patients with mUC composed 2 cohorts. Cohort 1 received first-line or second-/third-line nivolumab with escalating doses of ipilimumab, and cohort 2 received second-/third-line nivolumab with high-dose ipilimumab. Recruitment spanned 26 sites in Germany and Austria from August 8, 2017, to February 18, 2021. All patients had a 70% or higher Karnofsky Performance Score and measurable disease per Response Evaluation Criteria in Solid Tumours, version 1.1.

Interventions

All patients initiated 4 doses of 240-mg nivolumab (1× every 2 wk). Week 8 nonresponders received nivolumab + ipilimumab (1× every 3 wk). Cohort 1 received 2 doses of 3-mg/kg nivolumab + 1-mg/kg ipilimumab followed by 2 doses of 1-mg/kg nivolumab + 3-mg/kg ipilimumab if no response. Due to safety concerns, cohort 1 treatment was halted, and first-line cohort 2 treatment was not pursued. Cohort 2 received 2 to 4 doses of 1-mg/kg nivolumab + 3-mg/kg ipilimumab. Responders continued with nivolumab maintenance but could receive nivolumab + ipilimumab for later progression.

Main Outcomes and Measures

The primary end point was objective response rate.

Results

The study comprised 169 patients (118 [69.8%] men; median [range] age, 68 [37-84] years): 86 in cohort 1 (42 first-line; 44 second-/third-line) and 83 in cohort 2. The median (IQR) follow-up times were 10.4 (4.2-23.5) months (first-line cohort 1), 7.5 (3.1-23.8) months (second-/third-line cohort 1), and 6.2 (3.2-22.7) months (cohort 2). Response rates to nivolumab induction were 12/42 (29%, first-line cohort 1), 10/44 (23%, second-/third-line cohort 1), and 17/83 (20%, cohort 2). Response rates to a tailored approach were 20/42 (48% [90% CI, 34%-61%], first-line cohort 1), 12/44 (27% [90% CI, 17%-40%], second-/third-line cohort 1), and 27/83 (33% [90% CI, 23%-42%], cohort 2). Three-year overall survival rates for first-line cohort 1, second-/third-line cohort 1, and cohort 2 using the Kaplan-Meier method were 32% (95% CI, 17%-49%), 19% (95% CI, 8%-33%), and 34% (95% CI, 23%-44%), respectively.

Conclusions and Relevance

In this nonrandomized trial, although first-line cohort 1 treatment improved objective response rates, considerable progression events urge caution with this as a first-line therapy. Second-/third-line cohort 1 treatment did not improve response rates compared with nivolumab monotherapy. However, added high-dose ipilimumab may improve tumor response and survival in patients with mUC.

Trial Registration

ClinicalTrials.gov Identifier: NCT03219775.

Die EU-Verordnung für In-vitro-Diagnostika (IVDR) in der Praxis: Umsetzung und Anwendung - Ergebnisse einer öffentlichen Veranstaltung der Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF) im März 2023

In order to discuss first experiences with the implementation of the EU Regulation on In Vitro Diagnostic Medical Devices (IVDR) about one year after its entry into force, the German Association of the Scientific Medical Societies (AWMF e.V.) organized a full-day public webinar. Overall, it became clear that the implementation of the IVDR still poses significant challenges for laboratory medicine and pathology. Corrections at the political level and implementation with a sense of proportion are required. Before the long-term goal of the IVDR, i.e. the increase in patient safety, can be realized, the prevention of disadvantages for patients due to gaps in care must be strived for in the medium term by all parties involved.

Non-invasive medical gas plasma augments bladder cancer cell toxicity in preclinical models and patient-derived tumor tissues

INTRODUCTION

Medical gas plasma therapy has been successfully applied to several types of cancer in preclinical models. First palliative tumor patients suffering from advanced head and neck cancer benefited from this novel therapeutic modality. The gas plasma-induced biological effects of reactive oxygen and nitrogen species (ROS/RNS) generated in the plasma gas phase result in oxidation-induced lethal damage to tumor cells.

OBJECTIVES

This study aimed to verify these anti-tumor effects of gas plasma exposure on urinary bladder cancer.

METHODS

2D cell culture models, 3D tumor spheroids, 3D vascularized tumors grown on the chicken chorion-allantois-membrane (CAM) in ovo, and patient-derived primary cancer tissue gas plasma-treated ex vivo were used.

RESULTS

Gas plasma treatment led to oxidation, growth retardation, motility inhibition, and cell death in 2D and 3D tumor models. A marked decline in tumor growth was also observed in the tumors grown in ovo. In addition, results of gas plasma treatment on primary urothelial carcinoma tissues ex vivo highlighted the selective tumor-toxic effects as non-malignant tissue exposed to gas plasma was less affected. Whole-transcriptome gene expression analysis revealed downregulation of tumor-promoting fibroblast growth factor receptor 3 (FGFR3) accompanied by upregulation of apoptosis-inducing factor 2 (AIFm2), which plays a central role in caspase-independent cell death signaling.

CONCLUSION

Gas plasma treatment induced cytotoxicity in patient-derived cancer tissue and slowed tumor growth in an organoid model of urinary bladder carcinoma, along with less severe effects in non-malignant tissues. Studies on the potential clinical benefits of this local and safe ROS therapy are awaited.

Tailored Immunotherapy Approach With Nivolumab in Advanced Transitional Cell Carcinoma

PURPOSE

Several anti-programmed cell death (ligand)-1 (PD-[L]1) immune checkpoint inhibitors are approved in advanced/metastatic urothelial carcinoma (mUC). Recently, improved activity of an anti-PD-1/anticytotoxic T-cell lymphocyte-4 (CTLA-4) combination versus anti-PD-1 monotherapy has been reported. We report a response-based approach starting treatment with nivolumab monotherapy with nivolumab/ipilimumab as immunotherapeutic boost.

METHODS

After four doses of nivolumab induction, responders continued with nivolumab maintenance therapy. Patients with stable/progressive disease received nivolumab 3 mg/kg plus ipilimumab 1 mg/kg once every 3 weeks for 2 doses followed by nivolumab 1 mg/kg plus ipilimumab 3 mg/kg once every 3 weeks for 2 doses, if not responding to the initial boost. Responders to boosts continued with nivolumab maintenance. Between July 2017 and April 2019, 86 patients were enrolled. The median follow-up is 7.7 months. The primary end point is objective response rate (ORR) per RECIST1.1. Secondary end points include efficacy of nivolumab induction, remission rate with nivolumab/ipilimumab boosts, overall survival, and safety.

RESULTS

Of all patients, 42, 39, and five were first- (1L), second- (2L), and third-line (3L), respectively. The median age was 68 years. The ORR with nivolumab monotherapy (assessed at week 8) was 29% in 1L and 23% in 2/3L, respectively. Forty-one patients received early (week 8) and 11 received later nivolumab/ipilimumab boosts. ORRs with nivolumab with or without nivolumab/ipilimumab (best overall response) were 45% and 27% in 1L and 2/3L, respectively. In 1L, 7 of 17 patients receiving boosts at week 8 improved, compared with 2 of 24 in 2/3L.

CONCLUSION

The tailored approach of TITAN-TCC shows meaningful clinical activity supporting dual checkpoint inhibition in 1L mUC. However, starting therapy with nivolumab exclusively appears inadequate given the aggressive nature of mUC. In 2/3L, nivolumab/ipilimumab boosts with escalating ipilimumab dose did not improve efficacy outcomes versus nivolumab monotherapy. An independent 2L cohort of TITAN-TCC receiving nivolumab 1 mg/kg plus ipilimumab 3 mg/kg once every 3 weeks for 4 doses is ongoing.

ScoMorphoFISH: A deep learning enabled toolbox for single-cell single-mRNA quantification and correlative (ultra-)morphometry

Increasing the information depth of single kidney biopsies can improve diagnostic precision, personalized medicine and accelerate basic kidney research. Until now, information on mRNA abundance and morphologic analysis has been obtained from different samples, missing out on the spatial context and single‐cell correlation of findings. Herein, we present scoMorphoFISH, a modular toolbox to obtain spatial single‐cell single‐mRNA expression data from routinely generated kidney biopsies. Deep learning was used to virtually dissect tissue sections in tissue compartments and cell types to which single‐cell expression data were assigned. Furthermore, we show correlative and spatial single‐cell expression quantification with super‐resolved podocyte foot process morphometry. In contrast to bulk analysis methods, this approach will help to identify local transcription changes even in less frequent kidney cell types on a spatial single‐cell level with single‐mRNA resolution. Using this method, we demonstrate that ACE2 can be locally upregulated in podocytes upon injury. In a patient suffering from COVID‐19‐associated collapsing FSGS, ACE2 expression levels were correlated with intracellular SARS‐CoV‐2 abundance. As this method performs well with standard formalin‐fixed paraffin‐embedded samples and we provide pretrained deep learning networks embedded in a comprehensive image analysis workflow, this method can be applied immediately in a variety of settings.

Efficacy and safety of erdafitinib in patients with locally advanced or metastatic urothelial carcinoma: long-term follow-up of a phase 2 study

BACKGROUND

Erdafitinib, a pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor, was shown to be clinically active and tolerable in patients with advanced urothelial carcinoma and prespecified FGFR alterations in the primary analysis of the BLC2001 study at median 11 months of follow-up. We aimed to assess the long-term efficacy and safety of the selected regimen of erdafitinib determined in the initial part of the study.

METHODS

The open-label, non-comparator, phase 2, BLC2001 study was done at 126 medical centres in 14 countries across Asia, Europe, and North America. Eligible patients were aged 18 years or older with locally advanced and unresectable or metastatic urothelial carcinoma, at least one prespecified FGFR alteration, an Eastern Cooperative Oncology Group performance status of 0-2, and progressive disease after receiving at least one systemic chemotherapy or within 12 months of neoadjuvant or adjuvant chemotherapy or were ineligible for cisplatin. The selected regimen determined in the initial part of the study was continuous once daily 8 mg/day oral erdafitinib in 28-day cycles, with provision for pharmacodynamically guided uptitration to 9 mg/day (8 mg/day UpT). The primary endpoint was investigator-assessed confirmed objective response rate according to Response Evaluation Criteria In Solid Tumors version 1.1. Efficacy and safety were analysed in all treated patients who received at least one dose of erdafitinib. This is the final analysis of this study. This study is registered with ClinicalTrials.gov, NCT02365597.

FINDINGS

Between May 25, 2015, and Aug 9, 2018, 2328 patients were screened, of whom 212 were enrolled and 101 were treated with the selected erdafitinib 8 mg/day UpT regimen. The data cutoff date for this analysis was Aug 9, 2019. Median efficacy follow-up was 24·0 months (IQR 22·7-26·6). The investigator-assessed objective response rate for patients treated with the selected erdafitinib regimen was 40 (40%; 95% CI 30-49) of 101 patients. The safety profile remained similar to that in the primary analysis, with no new safety signals reported with longer follow-up. Grade 3-4 treatment-emergent adverse events of any causality occurred in 72 (71%) of 101 patients. The most common grade 3-4 treatment-emergent adverse events of any cause were stomatitis (in 14 [14%] of 101 patients) and hyponatraemia (in 11 [11%]). There were no treatment-related deaths.

INTERPRETATION

With longer follow-up, treatment with the selected regimen of erdafitinib showed consistent activity and a manageable safety profile in patients with locally advanced or metastatic urothelial carcinoma and prespecified FGFR alterations.

FUNDING

Janssen Research & Development.

Gelsolin Governs the Neuroendocrine Transdifferentiation of Prostate Cancer Cells and Suppresses the Apoptotic Machinery

BACKGROUND/AIM

Interleukin 6 (IL6) is increased in patients with progressive prostate cancer and induces its transdifferentiation to neuroendocrine prostate cancer. Neuroendocrine prostate cancer has become one of the greatest challenges in treating castration-resistant disease and is linked to poor prognosis. It is necessary to understand better the cellular events associated with IL6-mediated neuroendocrine differentiation to prevent it and identify potential new therapeutic targets.

MATERIALS AND METHODS

In the present study, an IL6-inducible neuroendocrine differentiation model established specifically for this purpose was applied using LNCaP cells. Proteomics and western blot analyses were used to identify proteins involved in neuroendocrine differentiation. Subsequently, the role of gelsolin (GSN) in the neuroendocrine differentiation model was characterized (knock-down analyses, microscopic co-localization analyses, apoptosis assay) and GSN expression levels in patient material were investigated.

RESULTS

This study revealed that GSN is a crucial factor in the neuroendocrine differentiation process.

CONCLUSION

It was shown that siRNA-mediated knock-down of GSN can inhibit neuroendocrine differentiation, making it a valid target for preventing IL6-mediated neuroendocrine differentiation.

Super-resolved local recruitment of CLDN5 to filtration slits implicates a direct relationship with podocyte foot process effacement

Under healthy conditions, foot processes of neighbouring podocytes are interdigitating and connected by an electron‐dense slit diaphragm. Besides slit diaphragm proteins, typical adherens junction proteins are also found to be expressed at this cell‐cell junction. It is therefore considered as a highly specialized type of adherens junction. During podocyte injury, podocyte foot processes lose their characteristic 3D structure and the filtration slits typical meandering structure gets linearized. It is still under debate how this change of structure leads to the phenomenon of proteinuria. Using super‐resolution 3D‐structured illumination microscopy, we observed a spatially restricted up‐regulation of the tight junction protein claudin‐5 (CLDN5) in areas where podocyte processes of patients suffering from minimal change disease (MCD), focal and segmental glomerulosclerosis (FSGS) as well as in murine nephrotoxic serum (NTS) nephritis and uninephrectomy DOCA‐salt hypertension models, were locally injured. CLDN5/nephrin ratios in human glomerulopathies and NTS‐treated mice were significantly higher compared to controls. In patients, the CLDN5/nephrin ratio is significantly correlated with the filtration slit density as a foot process effacement marker, confirming a direct association of local CLDN5 up‐regulation in injured foot processes. Moreover, CLDN5 up‐regulation was observed in some areas of high filtration slit density, suggesting that CLND5 up‐regulation preceded the changes of foot processes. Therefore, CLDN5 could serve as a biomarker predicting early foot process effacement.

FC 017DEEP-LEARNING ENABLED QUANTIFICATION OF SINGLE-CELL SINGLE-MRNA TRANSCRIPTS AND CORRELATIVE SUPER-RESOLVED PODOCYTE FOOT PROCESS MORPHOMETRY IN ROUTINE KIDNEY BIOPSY SPECIMEN

Background and Aims

Although high-throughput single-cell transcriptomic analysis, super-resolution light microscopy and deep-learning methods are broadly used, the gold-standard to evaluate kidney biopsies is still the histologic assessment of formalin-fixed and paraffin embedded (FFPE) samples with parallel ultrastructural evaluation. Recently, we and others have shown that super-resolution fluorescence microscopy can be used to study glomerular ultrastructure in human biopsy samples. Additionally, in the last years mRNA in situ hybridization techniques have been improved to increase specificity and sensitivity to enable transcriptomic analysis with single-mRNA resolution (smFISH).

Method

For smFISH, we used the fluorescent multiplex RNAscope kit with probes targeting ACE2, WT1, PPIB, UBC and POLR2A. To find an on-slide reference gene, the normfinder algorithm was used. The smFISH protocol was combined with a single-step anti-podocin immunofluorescence enabled by VHH nanobodies. Podocytes were labeled by tyramide-signal amplified immunofluorescence using recombinant anti-WT1 antibodies. Slides were imaged using confocal laser scanning, as well as 3D structured illumination microscopy. Deep-learning networks to segment glomeruli and cell nuclei (UNet and StarDist) were trained using the ZeroCostDL4Mic approach. Scripts to automate analysis were developed in the ImageJ1 macro language.

Results

First, we show robust functionality of threeplex smFISH in archived routine FFPE kidney biopsy samples with single-mRNA resolution. As variations in sample preparation can negatively influence mRNA-abundance, we established PPIB as an ideal on-slide reference gene to account for different RNA-integrities present in biopsy samples. PPIB was chosen for its most stable expression in microarray dataset of various glomerular diseases determined by the Normfinder algorithm as well as its smFISH performance.

To segment glomeruli and to label glomerular and tubulointerstitial cell subsets, we established a combination of smFISH and immunofluorescence. As smFISH requires intense tissue digestion to liberate cross-linked RNAs, immunofluorescence protocols had to be adapted: For podocin, a small-sized single-step label approach enabled by small nanobodies and for WT1, tyramide signal amplification was used.

For enhanced segmentation performance, we used deep learning: First, a network was customized to recognize DAPI+ cell nuclei and WT1/DAPI+ podocyte nuclei. Second, a UNet was trained to segment glomeruli in podocin-stained tissue sections. Using these segmentation masks, we could annotate PPIB-normalized single mRNA transcripts to individual cells. We established an ImageJ script to automatize transcript quantification.

As a proof-of-principle, we demonstrate inverse expression of WT1 and ACE2 in glomerular vs. tubulointerstitial single cells. Furthermore, in the podocyte subset, WT1 highly clustered whereas no significant ACE2 expression was found under baseline conditions.

Additionally, when imaged with super-resolution microscopy, podocyte filtration slit morphology could be visualized The optical resolution was around 125 nm and therefore small enough to resolve individual foot processes. The filtration slit density as a podocyte-integrity marker did not differ significantly from undigested tissue sections proving the suitability for correlative podocyte foot process morphometry with single-podocyte transcript analysis.

Conclusion

Here we present a modular toolbox which combines algorithms for multiplexed, normalized single-cell gene expression with single mRNA resolution in cellular subsets (glomerular, tubulointerstitial and podocytes). Additionally, this approach enables correlation with podocyte filtration slit ultrastructure and gross glomerular morphometry.

Tailored immunotherapy approach with nivolumab in advanced transitional cell carcinoma (TITAN-TCC)

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Background: Several PD-1 immune-checkpoint inhibitors including Nivolumab (Nivo) are approved in urothelial cancer. Recently, in the front line setting, improved activity of combined PD-L1 and CTLA4 immune-checkpoint inhibition has been reported and a phase III trial with Nivolumab + Ipilimumab (Nivo+Ipi) is ongoing. Here we report a response-based tailored approach starting treatment with Nivo monotherapy using Nivo+Ipi as immunotherapeutic “boost”. Methods: Between July 2017 and April 2019 86 patients were enrolled and treated according to protocol version 3 (cohort 1). Patients started with Nivo 240 mg Q2W induction. After 4 dosings and tumor assessment at week 8 (i) responders (PR/CR) to Nivo monotherapy continued with maintenance while (ii) patients with stable (SD) or progressive disease (PD) received 2 cycles Nivo3+Ipi1 followed by another 2 cycles Nivo1+Ipi3 if not responding. Median follow-up is 8.7 months. The primary endpoint is confirmed investigator-assessed objective response rate (ORR) per RECIST1.1. Secondary endpoints include activity of Nivo monotherapy at week 8, remission rate with Nivo+Ipi “boosts”, safety, overall survival and quality of life. Results: Of the patients 42, 39 and 5 were first, second and third line, respectively. Median age was 67 years (range 45-84), 61 patients (71 %) were male and 25 female. ORR with Nivo monotherapy at first assessment (week 8) was 29 % and 23 % in first and second/third line, respectively. Of the patients 41 received Nivo+Ipi “boosts” after week 8 while 12 received later “boosts”. Best overall response (BOR) rate with Nivo induction ± Nivo+Ipi “boosts” was 48 % and 27 % in first and second/third line, respectively. In first line 7/17 (41 %) patients receiving Nivo+Ipi after week 8 had an improved response compared to 2/24 (8.3 %) in second/third line. Of the patients who continued with Nivo maintenance after week 8 and received later “boosts” 2/12 (17 %) had a PR and 2/12 (17 %) improved to SD. Treatment-related AEs will be presented. Conclusions: TITAN–TCC explores a response-driven use of Nivo+Ipi as an immunotherapeutic “boost”. In first line, this significantly improved ORR compared to the expected response rate of Nivo monotherapy, providing further evidence to the added value of Ipi in combination with Nivo. Further follow-up is ongoing to characterize duration and depth of response. Clinical trial information: NCT03219775 . Research Sponsor: Bristol-Myers Squibb[Table: see text]

BK virus-induced nephritis and cystitis after matched unrelated donor stem cell transplantation: A case report

Currently, there is no standard therapy for a BK virus infection of the urogenital tract in immunocompromised, stem cell transplanted patients, so that early diagnosis and introduction of supportive measures have the highest response rates to date.

Standardization in biobanking – between cooperation and competition

This article presents the current situation of German biobanks and shows future fields of action in the European and international context on the basis of upcoming legal and normative challenges. It gives an overview of the development of the international biobank standard ISO 20387 and the commitment of German biobank experts in the ISO committee TC276. Less attention than the biobank standard per se has so far been paid to the basic mechanisms by which standards are developed and the potential of their application and accreditation. In this sense, this article deals with the motivation for active participation in standardization projects. We discuss the status of ISO 20387 as a conformity assessment standard and the consequence of accreditation as a performance monitor.

Nicotinamide N-Methyltransferase and Its Precursor Substrate Methionine Directly and Indirectly Control Malignant Metabolism During Progression of Renal Cell Carcinoma

BACKGROUND/AIM

Renal cell carcinoma (RCC) is one of the most common tumor diseases in adults, and new specific biomarkers are urgently needed to define diagnosis and prognosis of patients with RCC as well as monitor the outcome of therapeutic interventions. The enzyme nicotinamide N-methyltransferase (NNMT) is believed to represent such a marker molecule in RCC therapy.

MATERIALS AND METHODS

NNMT expression was examined by western blotting in samples from patients with RCC and in RCC cell lines. Effects of NNMT on cell growth and metabolism were assessed using the Hoechst 33342 reagent assay and Vita-Orange cell viability assay. Incubation experiments were performed to study the influence of methionine and interleukin-6 (IL6) on expression of NNMT.

RESULTS

In patient samples, NNMT was up-regulated depending on the stage of progression. Investigations in an RCC cell culture model showed that after modulation of NNMT expression, cellular metabolism, but not cell growth was affected. This regulatory function was also dependent on the presence of the NNMT precursor substrate methionine and IL6.

CONCLUSION

The metabolism-regulatory activity of NNMT depends on the precursor substrate methionine and the presence of IL6. The function of methionine appears to be dependent on the stage of progression, since in individual RCC cell lines, opposing effects on metabolism were demonstrated. This, in turn, reflects the thoroughly complex situation in the clinic.

The androgen receptor antagonist enzalutamide induces apoptosis, dysregulates the heat shock protein system, and diminishes the androgen receptor and estrogen receptor β1 expression in prostate cancer cells

Enzalutamide's accepted mode of action is by targeting the androgen receptor's (AR) activity. In clinical practice, enzalutamide demonstrates a good benefit-risk profile for the treatment of advanced prostate cancer (PC), even after poor response to standard antihormonal treatment. However, since both, well-established antiandrogens and enzalutamide, target AR functionality, we hypothesized that additional unknown mechanisms might be responsible for enzalutamide's superior anticancer activity. In the current study, PC cells were incubated with enzalutamide and enzalutamide-dependent modulation of apoptotic mechanisms were assessed via Western blot analysis, TDT-mediated dUTP-biotin nick end-labeling assay, and nuclear morphology assay. Alterations of heat shock protein (HSP), AR, and estrogen receptor (ER) expression were examined by Western blot analysis. Enzalutamide attenuated the proliferation of PC cells in a time- and dose-dependent manner. In the presence of enzalutamide, apoptosis occurred which was shown by increased BAX expression, decreased Bcl-2 expression, nuclear pyknosis, and genomic DNA fragmentation. Moreover, enzalutamide inhibited the expression of HSPs primarily involved in steroid receptor stabilization and suppressed AR and ERβ1 expression. This study demonstrates for the first time that enzalutamide treatment of PC cells triggers varying molecular mechanisms resulting in antiproliferative effects of the drug. In addition to the well-characterized antagonistic inhibition of AR functionality, we have shown that enzalutamide also affects the intracellular synthesis of steroid receptor-associated HSPs, thereby diminishing the expression of AR and ERβ1 proteins and inducing apoptotic pathways. According to an indirect attenuation of HSP-associated factors such as steroid receptors, endometrial carcinoma, uterine leiomyosarcoma, and mamma carcinoma cells also demonstrated inhibited cell growth in the presence of enzalutamide. Our data, therefore, suggest that enzalutamide's high efficacy is at least partially independent of AR and p53 protein expression, which are frequently lost in advanced PC.

Cabazitaxel inhibits prostate cancer cell growth by inhibition of androgen receptor and heat shock protein expression

PURPOSE

Cabazitaxel, a semi-synthetic taxane of the third generation, inhibits prostate cancer (PC) cell growth by affecting the microtubule architecture. Since cabazitaxel has also been demonstrated to inhibit androgen receptor (AR) functionality, AR and AR-associated heat shock protein (HSP) expressions in the presence of cabazitaxel were characterized.

METHODS

AR and HSP expressions were assessed via Western blotting utilizing a PC-cell-line in vitro system incubated with cabazitaxel.

RESULTS

Incubation experiments with 0.3 nM cabazitaxel exhibited significantly reduced levels of AR and the AR-associated factors HSP90α, HSP40, and HSP70/HSP90 organising protein. Furthermore, expression of the anti-apoptotic factor HSP60 was suppressed. In contrast to other anticancer compounds, cabazitaxel did not alter the cytoprotective chemoresistance factor HSP27.

CONCLUSIONS

Despite the deregulation of microtubule organisation, cabazitaxel has been shown to suppress the expression of HSP. Very notably, and may be as a result of down-regulated HSP, cabazitaxel additionally inhibits the expression of the AR in AR-positive PC cells. Thus, cabazitaxel bears an additional anti-proliferative activity which is at least in part specific for PC cells.

SWITCH II: Phase III randomized, sequential, open-label study to evaluate the efficacy and safety of sorafenib-pazopanib versus pazopanib-sorafenib in the treatment of advanced or metastatic renal cell carcinoma (AUO AN 33/11)

PURPOSE

This trial compared the sequential therapy with the multikinase inhibitor sorafenib (So) followed by pazopanib (Pa) or vice versa in advanced/metastatic renal cell carcinoma (mRCC) patients.

METHODS

This multicenter, randomized phase 3 study assessed the sequential use of So-Pa versus Pa-So in patients with mRCC without prior systemic therapy. Pts were randomized to So 2 × 400 mg/day followed by Pa 1 × 800 mg/day in case of progression or intolerable toxicity or vice versa. Primary endpoint was total PFS (tPFS), defined as time from randomization to progression, or death during second-line therapy. Key secondary endpoints included overall survival (OS), first-line PFS, disease control rate (DCR) and safety.

RESULTS

A total of 377 pts were randomized (So-Pa, n = 189; Pa-So, n = 188). Recruitment of a total 544 pts was calculated, but actual accrual rate turned out to be lower than expected. The primary endpoint median tPFS was 8.6 mo (95% CI 7.7-10.2) for So-Pa and 12.9 mo (95% CI 10.8-15.2) for Pa-So with a hazard ratio (HR) of 1.36 (upper limit of one-sided 95% CI 1.68), which exceeded a predefined HR <1.225 as a one-sided 95% confidence interval. Non-inferiority of So-Pa regarding tPFS was not met. Secondary endpoints displayed marked statistical differences in favor of Pa-So in first-line PFS and DCR but not for OS and 2nd-line PFS. Side effect profiles were consistent with known toxicities of the respective multikinase-inhibitor including diarrhea, fatigue, hand-foot skin reaction and hypertension.

CONCLUSIONS

Non-inferiority of the primary endpoint tPFS could not be demonstrated for So-Pa. The results for first-line PFS and DCR favored the Pa-So sequence.

TRIAL REGISTRATION

NCT01613846, www.clinicaltrials.gov.

Enemy recognition is linked to soldier size in a polymorphic stingless bee

Many ant and termite colonies are defended by soldiers with powerful mandibles or chemical weaponry. Recently, it was reported that several stingless bee species also have soldiers for colony defence. These soldiers are larger than foragers, but otherwise lack obvious morphological adaptations for defence. Thus, how these soldiers improve colony fitness is not well understood. Robbing is common in stingless bees and we hypothesized that increased body size improves the ability to recognize intruders based on chemosensory cues. We studied the Neotropical species Tetragonisca angustula and found that large soldiers were better than small soldiers at recognizing potential intruders. Larger soldiers also had more olfactory pore plates on their antennae, which is likely to increase their chemosensory sensitivity. Our results suggest that improved enemy recognition might select for increased guard size in stingless bees.

BDNF: mRNA expression in urine cells of patients with chronic kidney disease and its role in kidney function

Podocyte loss and changes to the complex morphology are major causes of chronic kidney disease (CKD). As the incidence is continuously increasing over the last decades without sufficient treatment, it is important to find predicting biomarkers. Therefore, we measured urinary mRNA levels of podocyte genes NPHS1, NPHS2, PODXL and BDNF, KIM‐1, CTSL by qRT‐PCR of 120 CKD patients. We showed a strong correlation between BDNF and the kidney injury marker KIM‐1, which were also correlated with NPHS1, suggesting podocytes as a contributing source. In human biopsies, BDNF was localized in the cell body and major processes of podocytes. In glomeruli of diabetic nephropathy patients, we found a strong BDNF signal in the remaining podocytes. An inhibition of the BDNF receptor TrkB resulted in enhanced podocyte dedifferentiation. The knockdown of the orthologue resulted in pericardial oedema formation and lowered viability of zebrafish larvae. We found an enlarged Bowman's space, dilated glomerular capillaries, podocyte loss and an impaired glomerular filtration. We demonstrated that BDNF is essential for glomerular development, morphology and function and the expression of BDNF and KIM‐1 is highly correlated in urine cells of CKD patients. Therefore, BDNF mRNA in urine cells could serve as a potential CKD biomarker.

MicroRNA-1 and MicroRNA-21 Individually Regulate Cellular Growth of Non-malignant and Malignant Renal Cells

BACKGROUND/AIM

Due to its poor prognosis, it is increasingly necessary to understand the biology of renal cell cancer (RCC). Therefore, we investigated the role of microRNAs miR-1 and miR-21 in the growth of RCC cells compared to that of non-malignant renal cells.

MATERIALS AND METHODS

Four malignant cell lines (Caki-1, 786-O, RCC4, A498) were examined regarding their cell growth, microRNA and telomerase expression, and were compared to non-malignant RC-124 renal cells.

RESULTS

Inconsistencies appeared in the panel of RCC cells regarding antiproliferative and proliferative properties of miR-1 and miR-21, respectively. Notably, and most likely due to immortaliziation, non-malignant RC-124 cells exhibited telomerase expression and activity.

CONCLUSION

miR-1 and miR-21 functionality in cancer progression, particularly in tumor growth, may be more dependent on the individual cellular context and may reflect RCC heterogeneity. Thus, both microRNAs, in combination with other stratifying biomarkers, may be useful in terms of RCC diagnosis, prognosis, or treatment response.

Transplantation of Free and Microencapsulated Islets in Rats: Evidence for the Requirement of An Increased Islet Mass for Transplantation into the Peritoneal Site

Microencapsulation of islets of Langerhans may avoid the necessity of a permanent immunosuppressive drug therapy and opens up new perspectives for xenotransplantation in the treatment of insulin dependent diabetes. In a mouse model we recently showed long-term normoglycemia after microencapsulated xenotransplantation. Since the acceptance of mice to any kind of foreign material is quite high we assume that the rat model better reflects the situation of higher mammalians or even humans. Due to the volume of the transplanted material (i.e. islets + alginate-capsule) only the peritoneal cavity can be used up to now. The quantity of islets necessary to normalize the non-fasting blood glucose level was much higher than expected and free transplants needed even a higher amount of islets than encapsulated ones (3000 encapsulated vs. 2 x 3000 non-encapsulated). Transplantation beneath the kidney capsule was successful with only 1200-1500 islets per rat proving the metabolic potency of the islets. Implantation of empty capsules did not alter the diabetic state. We conclude that the alginate matrix may act as a “spacer” creating a distance between the consuments of a lacking substrate esp. oxygen in an unfavourable environment and perhaps protect it from unspecific mediators released during the postoperative period. Our findings underline the necessity for smaller capsules that would enable us to use other transplantation sites.

Transplantation of parathyroid tissue in experimental hypoparathyroidism: in vitro and in vivo function of parathyroid tissue microencapsulated with a novel amitogenic alginate

Microencapsulation of tissues is an alternative to postoperative immunosuppression in transplantation. In 1994 iso-, allo- and xenotransplantation of microencapsulated parathyroid tissue was achieved in vivo. However, continued analysis of the coating substance (an alginate) determined mitogenic properties. Here, we report on the in vitro and in vivo function of parathyroid tissue microencapsulated with a novel amitogenic alginate suitable for use in humans. To assess in vitro function, parathyroid tissue encapsulated with mitogenic and amitogenic alginate was exposed to rising concentrations of calcium. For in vivo experiments, it was isotransplanted into parathyroidectomized rats. PTH release into medium and PTH serum levels as well as calcium levels of recipient rats were analyzed and compared to native (non-microencapsulated) tissue and empty capsules, respectively. In vivo, transplants were excised and subjected to histologic examination six months after trans-plantation. In vitro, parathyroid tissue encapsulated with amitogenic alginate releases approximately half of the PTH of native tissue, not different from tissue encapsulated with the mitogenic alginate. In vivo, the novel alginate preserved parathyroid function similar to that of native tissue over the six month period resulting in complete reversal of hypoparathyroidism. Correspondingly, histologic examination revealed vital parathyroid tissue in intact microcapsules. By establishing in vitro function and successful long-term transplantation, we have documented the principle of microencapsulation of parathyroid tissue to be effective also with the novel amitogenic alginate, which is suitable for clinical use.

PDZ domain containing protein 1 (PDZK1), a modulator of membrane proteins, is regulated by the nuclear receptor THRβ

Genome wide association studies revealed single nucleotide polymorphisms (SNP) located within the promoter of PDZ domain containing protein 1 (PDZK1) to be associated with serum uric acid levels. Since modulation of transporters and particularly of membrane proteins involved in uric acid handling by PDZK1 has previously been reported, the aim of this study was to analyze the impact of the polymorphisms rs1967017, rs1471633, and rs12129861 on promoter activity and thereby transcription of PDZK1. Cell-based reporter gene assays showed transactivation of the PDZK1-promoter by triiodothyronine mediated by thyroid hormone receptors (THR) α and β. In silico analysis verified localization of the polymorphism rs1967017 within the most likely THR binding site whose deletion reduced THR-mediated transactivation. Furthermore, our study shows regulation of PDZK1 by thyroid hormones, thereby providing a mechanistic basis for the previously reported associations between thyroid hormone status and uric acid homeostasis.

Structured illumination microscopy and automatized image processing as a rapid diagnostic tool for podocyte effacement

The morphology of podocyte foot processes is obligatory for renal function. Here we describe a method for the superresolution-visualization of podocyte foot processes using structured illumination microscopy of the slit diaphragm, which before has only been achieved by electron microscopy. As a proof of principle, we measured a mean foot process width of 0.249 ± 0.068 µm in healthy kidneys and a significant higher mean foot process width of 0.675 ± 0.256 µm in minimal change disease patients indicating effacement of foot processes. We then hypothesized that the slit length per glomerular capillary surface area (slit diaphragm density) could be used as an equivalent for the diagnosis of effacement. Using custom-made software we measured a mean value of 3.10 ± 0.27 µm⁻¹ in healthy subjects and 1.83 ± 0.49 µm⁻¹ in the minimal change disease patients. As foot process width was highly correlated with slit diaphragm density (R² = 0.91), we concluded that our approach is a valid method for the diagnosis of foot process effacement. In summary, we present a new technique to quantify podocyte damage, which combines superresolution microscopy with automatized image processing. Due to its diverse advantages, we propose this technique to be included into routine diagnostics of glomerular histopathology.

Microvascular and lymphovascular tumour invasion are associated with poor prognosis and metastatic spread in renal cell carcinoma: a validation study in clinical practice

OBJECTIVE

To validate microvascular (MVI) and lymphovascular (LVI) invasion as prognostic factors in patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

Data of patients with RCC who underwent radical or nephron-sparing surgery were prospectively collected from three academic centres. The occurrence of MVI and LVI was determined with standard staining protocols by experienced pathologists at the time of diagnosis. The association of MVI and LVI with clinicopathological data, metastatic spread, and cancer-specific survival (CSS) were evaluated with Fisher's exact tests, binary logistic regression analyses, and univariable and multivariable Cox proportional hazard regression models.

RESULTS

MVI was present in 201 of 747 patients (26.9%) and was associated with advanced Tumour-Node-Metastasis (TNM) stages, high Fuhrman grades, and sarcomatoid features (all P < 0.001). MVI was associated with a higher rate of metastatic spread. LVI was present in 32 of 573 patients (5.5%) and was associated with advanced TNM stages, high Fuhrman grade, and sarcomatoid features (all P < 0.001). Two-thirds of LVI-positive patients died (P < 0.001). Both LVI and MVI were significantly associated with CSS in all patients, clear cell RCC (ccRCC), and localised RCC in univariable analysis (all P < 0.001). On multivariable analysis, presence of MVI was identified as an independent prognostic factor (hazard ratio 2.09; P = 0.001). Moreover, MVI [odds ratio (OR) 2.7; P = 0.001] and not macrovascular invasion (P = 0.895) was an independent predictor of sychronuous metastatic spread. LVI was the strongest factor associated with sychronous metastatic spread (OR 4.73, 95% confidence interval 1.84-12.14; P = 0.001) in all patients and in the subgroup of patients with ccRCC (P = 0.001).

CONCLUSIONS

The present study validated LVI and MVI as prognostic factors for poor outcome in RCC. These findings endorse an evaluation of both variables in the clinical routine setting to facilitate survival prognostication in follow-up protocols and for assignment to adjuvant treatment trials.

Regulation of PDZ domain-containing 1 (PDZK1) expression by hepatocyte nuclear factor-1α (HNF1α) in human kidney

In the renal proximal tubule the secretion and reabsorption of glomerularly filtrated compounds is realized by a functional network of uptake and efflux transporters. The activity and localization of several transporters expressed at the apical tubular membrane are regulated by the membrane-associated protein PDZ domain-containing 1 (PDZK1). We aimed to characterize the transcriptional regulation of this modulator of renal transport. Coexpression analyses of PDZK1 and putative regulators were performed using human kidney samples. Protein and mRNA expression of PDZK1 in renal proximal tubule epithelial cells after adenoviral transfer and siRNA knockdown of transcription factor hepatocyte nuclear factor-1α (HNF1α) was assessed by quantitative real-time PCR and Western blot analysis. Transactivation of the PDZK1 promoter was quantified in cell-based reporter gene assays. Subsequently, the binding of HNF1α to the PDZK1 promoter was verified by in silico analyses and chromatin immunoprecipitation assay. HNF1α positively regulated the promoter activity of PDZK1. Adenoviral overexpression of HNF1α in renal proximal tubule epithelial cells (RPTEC) increased PDZK1 mRNA and protein expression, whereas siRNA knockdown of HNF1α resulted in decreased expression of PDZK1. Our results show that HNF1α, which has previously been described as a modulator of several transporters of the renal transportosome, is also a key determinant of PDZK1 transcription.

Fractions from Commercial Collagenase Preparations: Use in Enzymic Isolation of the Islets of Langerhans from Porcine Pancreas

Transplantation of isolated islets of Langerhans is an intriguing possibility for the treatment of diabetes mellitus. The isolation of islets from pancreata requires the specific dissociation of the tissue. Commercial collagenases from Clostridium histolyticum are widely used for this purpose. Unfortunately, the effectiveness of these commercial enzymes is not predictable and differs considerably between suppliers and even from lot to lot. This is due mainly to differences in their specific collagenase activity and to the presence of other lytic enzymes, as well as to other contaminants. Free flow zone electrophoresis (FFZE) was used to separate the effective protein components from undesired compounds and to prepare a digestive enzyme mixture with controlled composition of lytic activities. Fractionation of crude collagenases by FFZE resulted in partially purified protein fractions that were enriched for collagenase and tryptic activities, and contained only trace amounts of neutral protease. These preparations proved to be highly effective in an in vitro assay for the liberation of viable islets from porcine pancreas. To scale up the production of these collagenases with defined enzyme composition, we fractionated two different lots of a commercial collagenase from C. histolyticum (one lot effective in islet isolation, the other not) by using fast protein liquid chromatography (FPLC) on hydroxyapatite. Again, high efficacy of islet release from pancreatic tissue was correlated to high specific tryptic and collagenase activities and low levels of neutral protease. The chromatographic protocol developed in this study converted a non-effective collagenase lot into a preparation that allowed successful islet isolation.

A behavioural syndrome, but less evidence for a relationship with cognitive traits in a spatial orientation context

BACKGROUND

Animals show consistent individual behavioural differences in many species. Further, behavioural traits (personality traits) form behavioural syndromes, characterised by correlations between different behaviours. Mechanisms maintaining these correlations could be constrained due to underlying relationships with cognitive traits. There is growing evidence for the non-independence of animal personality and general cognitive abilities in animals, but so far, studies on the direction of the relationship between them revealed contradictory results. Still, it is hypothesised that individuals may exhibit consistent learning and decision styles. Fast behavioural types (consistently bolder and more active individuals) are expected to show faster learning styles. Slow behavioural types in contrast are assumed to learn slower but more accurately. This can be caused by a speed-accuracy trade-off that individuals face during decision making. We measured the repeatability of three personality and four spatial cognitive traits in adult Eurasian harvest mice (Micromys minutus). We analysed correlations among personality traits (behavioural syndrome). We further investigated the relationships between personality and spatial cognitive traits as a first step exploring the potential connection between personality and cognition in this species.

RESULTS

Our results showed that exploration, activity and boldness were repeatable in adult mice. Spatial recognition measured in a Y Maze was also significantly repeatable, as well as spatial learning performance and decision speed. We found no repeatability of decision accuracy. Harvest mice showed a behavioural syndrome as we observed strong positive correlations between personality traits. The speed-accuracy trade-off was not apparent within, nor between individuals. Nevertheless, we found weak evidence for a relationship between personality and spatial cognitive traits as fast behavioural types learned a spatial orientation task faster than slow types, and shyer harvest mice made decisions quicker than bolder mice.

CONCLUSIONS

Given these correlations, our data provided some first insights into the relationship between personality and spatial cognitive traits in harvest mice and will hopefully stimulate more studies in this field.

In Vitro Cultivation of Primary Prostate Cancer Cells Alters the Molecular Biomarker Pattern

BACKGROUND/AIM

The high variability of primary cells propagated in vitro led us to study the expression patterns of 11 most commonly accepted and widely used biomarkers specific for prostate cancer (PC) cells in primary cell models.

MATERIALS AND METHODS

Primary PC cells from five PC patients were partially subjected to RNA preparation immediately and remaining cells were propagated up to 84 days followed by RNA preparation. Subsequently, biomarker mRNA quantification was performed by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and biomarker transcript concentrations before and after cultivation of primary PC cells were compared.

RESULTS

Evaluation of androgen receptor, prostate-specific antigen, acid phosphatase, prostate-specific membrane antigen, fatty acid synthase, cytokeratin types 5/8/19, E-cadherin, epithelial cell adhesion molecule and fibroblast-specific protein 1 demonstrated temporal changes, as well as individual differences in expression, during primary PC cell propagation.

CONCLUSION

Experimental design, as well as data evaluation, may need to take under consideration the high variability of biomarker expression in primary PC cells.

Modulation of expression of the nuclear receptor NR0B2 (small heterodimer partner 1) and its impact on proliferation of renal carcinoma cells

Mammalian nuclear receptors (NRs) are transcription factors regulating the expression of target genes that play an important role in drug metabolism, transport, and cellular signaling pathways. The orphan and structurally unique receptor small heterodimer partner 1 (syn NR0B2) is not only known for its modulation of drug response, but has also been reported to be involved in hepatocellular carcinogenesis. Indeed, previous studies show that NR0B2 is downregulated in human hepatocellular carcinoma, suggesting that NR0B2 acts as a tumor suppressor via inhibition of cellular growth and activation of apoptosis in this tumor entity. The aim of our study was to elucidate whether NR0B2 may also play a role in other tumor entities. Comparing NR0B2 expression in renal cell carcinoma and adjacent nonmalignant transformed tissue revealed significant downregulation in vivo. Additionally, the impact of heterologous expression of NR0B2 on cell cycle progression and proliferation in cells of renal origin was characterized. Monitoring fluorescence intensity of resazurin turnover in RCC-EW cells revealed no significant differences in metabolic activity in the presence of NR0B2. However, there was a significant decrease of cellular proliferation in cells overexpressing this NR, and NR0B2 was more efficient than currently used antiproliferative agents. Furthermore, flow cytometry analysis showed that heterologous overexpression of NR0B2 significantly reduced the amount of cells passing the G1 phase, while on the other hand, more cells in S/G2 phase were detected. Taken together, our data suggest that downregulation of NR0B2 may also play a role in renal cell carcinoma development and progression.

Knockdown of ApoL1 in Zebrafish Larvae Affects the Glomerular Filtration Barrier and the Expression of Nephrin

APOL1, a secreted high-density lipoprotein, is expressed in different human tissues. Genetic variants of APOL1 are described to be associated with the development of end stage renal diseases in African Americans. In human kidney, APOL1 is mainly expressed in podocytes that are responsible for proper blood filtration. Since mice do not express ApoL1, the zebrafish is an ideal model to study the role of ApoL1. Injection of morpholinos against zApoL1 into zebrafish eggs and larvae, respectively, induces severe edema indicating a leakage of the filtration barrier. This was demonstrated in zApoL1 knockdown larvae by intravascular injection of fluorescently-labeled 10- and 500-kDa dextrans and by clearance of the vitamin D-binding protein from the circulation. Immunohistochemistry and RT-PCR revealed the reduction of nephrin, a podocyte-specific protein essential for blood filtration. Coinjection of human nephrin mRNA rescued the zApoL1 knockdown induced phenotype. Reduced APOL1 and nephrin levels were also found in biopsies of patients suffering from end stage renal diseases. Our results demonstrate that zApoL1 is essential for proper blood filtration in the zebrafish glomerulus and that zApoL1 affects the expression of nephrin.

Exosomal particles secreted by prostate cancer cells are potent mRNA and protein vehicles for the interference of tumor and tumor environment

BACKGROUND

Remodeling of the tumor environment and the modulation of tumor associated non-malignant cells are essential events in tumor progression. Exosomes are small membranous vesicles of 50-150 nm in diameter, which are secreted into the extracellular space and supposedly serve as vehicles for signal and effector molecules to modulate adjacent target cells. We characterized the mRNA and protein composition as well as cellular functions of prostate cancer cell-derived exosomes.

METHODS

Exosomes were prepared from prostate cancer cell culture supernatant by ultracentrifugation and subsequently characterized by dynamic light scattering and electron microscopy. Exosomal mRNA and protein composition were analyzed by DNA microarrays and gel electrophoresis coupled with mass spectrometry. Physiological effects of exosomes were studied by means of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase release cell assays. Using a SILAC approach, putative uptake of exosomal human proteins in canine cells and canine de novo synthesis of proteins specified by exosome-transferred human mRNA was analyzed in MDCK cells via mass spectrometry.

RESULTS

Preparations of exosomes revealed typical cup shaped particles of 150 nm in diameter. Analysis of mRNA and protein composition of exosomes exhibited a wide range of mRNA and protein species. Interestingly, the packaging of at least small proteins into exosomes was apparently unspecific, as shown with the example of two model proteins. In cell culture incubation experiments exosomal preparations of prostate cancer cells caused anti-proliferative effects. MS analysis revealed the uptake of exosomal human proteins into canine cells after 6 hr of incubation.

CONCLUSIONS

The results reveal a distinct exosomal functionality in the modulation of the prostatic tumor adjacent environment. The multitude of translocated factors implies the induction of numerous effects in tumor-associated target cells, including impact on cellular growth.

Isoform 1 of TPD52 (PC-1) promotes neuroendocrine transdifferentiation in prostate cancer cells

The tumour protein D52 isoform 1 (PC-1), a member of the tumour protein D52 (TPD52) protein family, is androgen-regulated and prostate-specific expressed. Previous studies confirmed that PC-1 contributes to malignant progression in prostate cancer with an important role in castration-resistant stage. In the present work, we identified its impact in mechanisms leading to neuroendocrine (NE) transdifferentiation. We established for long-term PC-1 overexpression an inducible expression system derived from the prostate carcinoma cell line LNCaP. We observed that PC-1 overexpression itself initiates characteristics of neuroendocrine cells, but the effect was much more pronounced in the presence of the cytokine interleukin-6 (IL-6). Moreover, to our knowledge, this is the first report that treatment with IL-6 leads to a significant upregulation of PC-1 in LNCaP cells. Other TPD52 isoforms were not affected. Proceeding from this result, we conclude that PC-1 overexpression enhances the IL-6-mediated differentiation of LNCaP cells into a NE-like phenotype, noticeable by morphological changes and increased expression of typical NE markers, like chromogranin A, synaptophysin or beta-3 tubulin. Immunofluorescent staining of IL-6-treated PC-1-overexpressing LNCaP cells indicates a considerable PC-1 accumulation at the end of the long-branched neuron-like cell processes, which are typically formed by NE cells. Additionally, the experimentally initiated NE transdifferentiation correlates with the androgen receptor status, which was upregulated additively. In summary, our data provide evidence for an involvement of PC-1 in NE transdifferentiation, frequently associated with castration resistance, which is a major therapeutic challenge in the treatment of advanced prostate cancer.

Effects of renal denervation on renal pelvic contractions and connexin expression in rats

AIMS

The renal pelvis shows spontaneous rhythmic contractile activity. We assessed to what extent this activity depends on renal innervation and studied the role of connexins in pelvic contractions.

METHODS

Rats underwent unilateral renal denervation or renal transplantation. Renal pelvic pressure and diuresis were measured in vivo. Spontaneous and agonist-induced contractions of isolated renal pelves were investigated by wire myography. Rat and human renal pelvic connexin mRNA abundances and connexin localization were studied by real-time PCR and immunofluorescence respectively.

RESULTS

Renal denervation or transplantation increased renal pelvic pressure in vivo by about 60 and 150%, respectively, but did not significantly affect pelvic contraction frequency. Under in vitro conditions, isolated pelvic preparations from innervated or denervated kidneys showed spontaneous contractions. Pelves from denervated kidneys showed about 50% higher contraction frequencies than pelves from innervated kidneys, whereas contraction force was similar in pelves from denervated and innervated kidneys. There was no denervation-induced supersensitivity to noradrenaline or endothelin-1. Renal denervation did not increase pelvic connexin37, 40, 43 or 45 mRNA abundances. Gap junction blockade had no effect on spontaneous pelvic contractile activity.

CONCLUSIONS

The denervation-induced effect on pelvic pressure may be the consequence of the enhanced diuresis. The mechanisms underlying the denervation-induced effects on pelvic contraction frequency remain unknown. Our data rule out a major role for two important candidates, by showing that renal denervation neither induced supersensitivity to contractile agonists nor increased connexin mRNA abundance in the pelvic wall.

Cytochrome P450 17A1 inhibitor abiraterone attenuates cellular growth of prostate cancer cells independently from androgen receptor signaling by modulation of oncogenic and apoptotic pathways

Abiraterone provides significant survival advantages in prostate cancer (PC), however, the current understanding of the molecular mechanisms of abiraterone is still limited. Therefore, the abiraterone impact on androgen receptor (AR)-positive LNCaP and AR-negative PC-3 cells was assessed by cellular and molecular analyses. The present study demonstrated, that abiraterone treatment significantly decreased cell growth, AR expression, and AR activity of AR-positive LNCaP cells. Notably, AR-negative PC-3 cells exhibited comparable reductions in cellular proliferation, associated with DNA fragmentation and pro-apoptotic modulation of p21, caspase-3, survivin, and transforming growth factor β (TGFβ). Our observations suggest that the attenuation of AR signaling is not the only rationale to explain the abiraterone anticancer activity. Abiraterone efficacy may play a more global role in PC progression control than originally hypothesized. In this regard, abiraterone is not only a promising drug for treatment of AR-negative PC stages, even more, abiraterone may represent an alternative for treatment of other malignancies besides prostate cancer.

Inhibition of Cell Growth of the Prostate Cancer Cell Model LNCaP by Cold Atmospheric Plasma

Backround/Aim: Physical plasmas are ionized gases containing several biologically-reactive factors that yet exert their anti-microbial and anti-proliferative effects in fields of surface sterilisation, de-contamination and wound healing.

MATERIALS AND METHODS

Cold atmospheric plasma (CAP) was generated via the atmospheric pressure plasma jet kINPen09. Apoptotic effects of CAP treatment on the human epithelial prostate cancer cell line LNCaP as a cell culture model for malignant tumor tissue was analyzed by cell counting, western blot and quantitative reverse transcription-polymerase chain reaction analysis.

RESULTS

LNCaP cells exhibited significantly reduced cell growth following CAP treatment. We show that most probably the induction of apoptosis is the terminus of CAP treatment illustrated by the pro-apoptotic modulation of p53, p21, caspase-3, Bax, and survivin, as well as morphological changes of cell architecture.

CONCLUSION

Our in vitro study offers first indicatory results for molecular response mechanisms after CAP treatment in a suitable LNCaP cell model.

Acceptance, Prevalence and Indications for Robot-Assisted Laparoscopy - Results of a Survey Among Urologists in Germany, Austria and Switzerland

Background: Robotic-assisted laparoscopy (RAL) is being widely accepted in the field of urology as a replacement for conventional laparoscopy (CL). Nevertheless, the process of its integration in clinical routines has been rather spontaneous. Objective: To determine the prevalence of robotic systems (RS) in urological clinics in Germany, Austria and Switzerland, the acceptance of RAL among urologists as a replacement for CL and its current use for 25 different urological indications. Materials and Methods: To elucidate the practice patterns of RAL, a survey at hospitals in Germany, Austria and Switzerland was conducted. All surgically active urology departments in Germany (303), Austria (37) and Switzerland (84) received a questionnaire with questions related to the one-year period prior to the survey. Results: The response rate was 63%. Among the participants, 43% were universities, 45% were tertiary care centres, and 8% were secondary care hospitals. A total of 60 RS (Germany 35, Austria 8, Switzerland 17) were available, and the majority (68%) were operated under public ownership. The perception of RAL and the anticipated superiority of RAL significantly differed between robotic and non-robotic surgeons. For only two urologic indications were more than 50% of the procedures performed using RAL: pyeloplasty (58%) and transperitoneal radical prostatectomy (75%). On average, 35% of robotic surgeons and only 14% of non-robotic surgeons anticipated RAL superiority in some of the 25 indications. Conclusions: This survey provides a detailed insight into RAL implementation in Germany, Austria and Switzerland. RAL is currently limited to a few urological indications with a small number of high-volume robotic centres. These results might suggest that a saturation of clinics using RS has been achieved but that the existing robotic capacities are being utilized ineffectively. The possible reasons for this finding are discussed, and certain strategies to solve these problems are offered.

Cold Atmospheric Plasma Treatment Induces Anti-Proliferative Effects in Prostate Cancer Cells by Redox and Apoptotic Signaling Pathways

One of the promising possibilities of the clinical application of cold plasma, so-called cold atmospheric plasma (CAP), is its application on malignant cells and cancer tissue using its anti-neoplastic effects, primarily through the delivery of reactive oxygen and nitrogen species (ROS, RNS). In this study, we investigated the impact of CAP on cellular proliferation and consecutive molecular response mechanisms in established prostate cancer (PC) cell lines. PC cells showed a significantly reduced cell growth following CAP treatment as a result of both an immediate increase of intracellular peroxide levels and through the induction of apoptosis indicated by annexin V assay, TUNEL assay, and the evaluation of changes in nuclear morphology. Notably, co-administration of N-acetylcysteine (NAC) completely neutralized CAP effects by NAC uptake and rapid conversion to glutathione (GSH). Vitamin C could not counteract the CAP induced effects on cell growth. In summary, relatively short treatments with CAP of 10 seconds were sufficient to induce a significant inhibition of cancer proliferation, as observed for the first time in urogenital cancer. Therefore, it is important to understand the mode of CAP related cell death and clarify and optimize CAP as cancer therapy. Increased levels of peroxides can alter redox-regulated signaling pathways and can lead to growth arrest and apoptosis. We assume that the general intracellular redox homeostasis, especially the levels of cellular GSH and peroxidases such as peroxiredoxins affect the outcome of the CAP treatment.