Receptor Activator of NF Kappa B (RANK) Expression Indicates Favorable Prognosis in Patients with Muscle-invasive Bladder Cancer.

BACKGROUND: Receptor activator of NF kappa B (RANK) and its ligand have an essential role in T-cell regulation and the development of bone metastases. The role of RANK expression in muscle-invasive bladder cancer (MIBC) is unknown. OBJECTIVE: To assess the relevance of RANK expression in patients with MIBC. DESIGN, SETTING, AND PARTICIPANTS: Expression of RANK was assessed via immunohistochemistry of benign urothelium, MIBC tissue, and lymph node metastases from 153 patients undergoing radical cystectomy. Expression data from The Cancer Genome Atlas (TCGA) cohort were analyzed for potential associations with molecular subtypes and outcome. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: RANK expression was correlated with clinical and pathological parameters and to individual data for the clinical course of MIBC. RESULTS AND LIMITATIONS: Expression of RANK was significantly higher in both primary tumors (p = 0.02) and lymph node metastases (p = 0.01) compared to normal urothelium. In tumor tissue, RANK expression was significantly lower in patients with locally advanced disease and lymph node involvement compared to those with organ-confined disease (p = 0.0009) and node-negative MIBC (p = 0.0002). In univariable and multivariable analyses, high expression of RANK was associated with a longer time to recurrence (p = 0.0005 and 0.01) and better cancer-specific (p = 0.0004 and 0.007) and overall survival (p = 0.002 and 0.04). High expression of RANK was associated with better outcome for patients with luminal infiltrated tumors in the TCGA cohort. CONCLUSIONS: RANK expression is increased in bladder cancer tissue compared to benign urothelium, with higher expression in organ-defined compared to locally advanced disease. High RANK expression indicates a favorable prognosis in MIBC. The prognostic role differs in tumors of different molecular subtypes. PATIENT SUMMARY: Expression of a protein involved in bone turnover regulation (RANK) is higher in bladder cancer tissue than in benign bladder tissue. However, high levels of RANK on tumor cells indicate favorable prognosis for patients with bladder cancer that invades the muscle layer of the bladder.

Prognostic impact of somatostatin receptor expression in advanced bladder cancer.

INTRODUCTION AND OBJECTIVES: Somatostatin receptors (SSTR) recently have been identified as potential targets for treatment of solid tumors. Furthermore, they have been shown to be of high relevance for tumor biology and prognosis in various types of cancer. However, there is a lack of clinical data for SSTR in bladder cancer (BC). Aim of this study was to determine the expression of all relevant somatostatin receptor subtypes in benign urothelium and tumor tissue of patients with muscle invasive BC. Furthermore, their potential role as prognostic factor for cancer-specific survival (CSS) and overall survival (OS) was evaluated. METHODS: The collective included BC and benign urothelium tissue of 103 patients (Median age 69; range 32-84, 79 male, 24 female) who underwent a radical cystectomy. A tissue microarray with subsequent immunohistochemical staining was used to assess membranous expression of SSTR1-5. Results were correlated to clinical and histopathological data as well as CSS and OS. RESULTS: Expressions of SSTR1-4 were significantly decreased in BC compared to benign urothelium (P < 0.002 each), whereas SSTR5 expression was increased (P = 0.0017). Expression of SSTR1 was associated with organ-confined disease (≤pT2) (P = 0.0477). No correlation between SSTR1-5 expression and N- and M-stage was observed. Univariate analyses showed a significantly longer CSS and OS in patients with high expression of SSTR3 (P = 0.0316 and 0.0044). Multivariate analyses confirmed SSTR3 expression as independent marker of improved CSS and OS (P = 0.0324 and 0.0076). CONCLUSIONS: The majority of somatostatin receptor subtypes exhibit decreased expression in BC compared to benign bladder tissue. Expression of SSTR3 is an indicator for favorable prognosis in patients with muscle-invasive BC. These results support preclinical investigations using somatostatin receptor analogues such as octreotide to influence BC growth.

Intratumoral Heterogeneity Determines the Expression of mTOR-pathway Proteins in Prostate Cancer.

The aim of this study was to evaluate the expression of mammalian target of rapamycin (mTOR), phosphorylated-mTOR (p-mTOR), and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) in prostate cancer (PCa) in order to assess intratumoral heterogeneity and correlation with clinicopathological parameters. Tissue samples from 115 patients undergoing radical prostatectomy were included in a tissue microarray comprising (A) tissue from the tumor center, (B) malignant border of the tumor, (C) tumor-adjacent benign tissue, and (D) tumor-distant benign prostatic tissue. Immune reactive scores 0-12 were correlated with clinical data in reference to localization. A meta-analysis of studies investigating the association between biochemical recurrence (BCR) and parameters of the mTOR pathway was conducted. Regardless of the location within the tumor, cancer tissue showed higher expression of mTOR, p-mTOR, and 4EB-P1 compared to benign tissue (p < 0.01). Significant differences in expression between tissue samples from groups C and D were observed for mTOR and p-mTOR. When considering expression according to the pathological stage, we observed lower p-mTOR expression in pT3 vs. pT2 (7.9 and 6.3; p = 0.01). After a median follow-up of 74.5 months (IQR 65.0-84.0), 27 patients (23.47%) developed BCR. Weak staining of mTOR was associated with shorter time to BCR (HR: 2.0; p = 0.049) after correcting for PSA and T stage. However, a significant association of mTOR expression with BCR was found for specimens from the malignant border of the tumor (B) but not the tumor center (A) (p = 0.0034 log rank). In a meta-analysis, we found that the expressions of mTOR ((RR) = 0.70; 95% CI 0.43-1.12; p = 0.13) and 4E-BP1 ((RR) = 0.86; p = 0.53) were not statistically associated with BCR, while strong staining of p-mTOR was associated with a lower risk of BCR ((RR) = 0.57; p = 0.002). All 3 markers showed stronger expression in PCa and exhibited local gradients in relation to the border of tumor and healthy tissue. Our results suggest an important role of intratumor heterogeneity for the use of mTOR parameters as biomarkers in PCa.

Systemic Alterations of Wnt Inhibitors in Patients with Prostate Cancer and Bone Metastases.

PURPOSE: Dickkopf-1 (DKK-1) and sclerostin seem to inhibit osteoblast activity by blocking the Wnt pathway, which leads to progression of metastatic prostate cancer (PC). However, it is unknown whether serum levels of these proteins are altered in PC patients with or without metastasis. The aim of this study was to assess DKK-1 and sclerostin serum levels in PC patients, including patients with bone metastases. METHODS: The study cohort (N = 143) consisted of 53 controls with benign prostatic hyperplasia (BPH), 43 with localized PC (PC cM0), and 47 had PC with metastasis (PC cM1). Serum levels of DKK-1 and sclerostin were measured by enzyme-linked immunosorbent assay. Results were compared using the Kruskal-Wallis tests; post hoc analysis was performed using the Tukey-Kramer test. RESULTS: Mean DKK-1 levels in patients with BPH (2809.4 pg/ml) (p < 0.001) as well as PC cM1 (2575.5 pg/ml) (p = 0.001) were significantly higher than in patients with PC cN0 cM0 (1551.8 pg/ml). Among PC cM1 patients, median DKK-1 levels were significantly lower in patients with castration-resistant disease compared to those with hormone-sensitive PC (p = 0.02); in contrast, sclerostin concentrations were elevated (p = 0.04). DKK-1 correlated with PSA in the cM1 group (p = 0.03) and sclerostin correlated with PSA in the PC group (0.01). CONCLUSIONS: DKK-1 is involved in the progression of PC. DKK-1-mediated inhibition of osteoblasts, which contributes to tumor progression and osteolytic metastases, may also play a role in the development of metastases with osteoblastic features. The use of DKK-1 antibodies should be considered for studies including metastatic PC patients.

Transketolase like 1 (TKTL1) expression alterations in prostate cancer tumorigenesis.

BACKGROUND: Prostate cancer (CaP) is the most common nonepidermal cancer in elderly males. Due to its heterogeneity and high variability in regards to clinical outcome and therapeutic response, urologists' handling of this disease remains a challenge. The objective of this study was to assess Transketolase like 1 (TKTL1) expression in benign prostatic tissue, peritumoral tissue and in CaP (in different stages of disease), and its correlation with clinicopathological findings, in order to detect if TKTL1 expression is associated with CaP tumorigenesis. METHODS: In total, 100 tissue samples were included: (i) 22 benign specimens, (ii) 46 specimens with nonmetastatic CaP, and (iii) 32 specimens from patients with metastatic CaP. From the tissue microarray slides, we evaluated immunohistochemically the expression of the TKTL1 protein, using the H-score. RESULTS: The TKTL1 protein expression pattern ranges from a low level in benign prostatic tissue (100 [57.5-105]), moderately low in peritumoral tissue (135.42 [100-195.16]), moderate expression in nonmetastatic CaP (200 [172.19-254.38]) to high in metastatic CaP (300 [222.50-300]). A significant rise of TKTL1 mean expression was seen throughout disease progression. A significant difference was also found in TKTL1 expression between peritumoral tissue and benign tissue. CONCLUSION: The results obtained in this study suggest that pentose phosphate pathway and its key enzyme TKTL1 is altered throughout the CaP tumorigenesis, and this pathway merits further investigation.

Transcripts of circulating tumor cells detected by a breast cancer-specific platform correlate with clinical stage in bladder cancer patients.

PURPOSE: There is increasing interest in circulating tumor cells (CTCs) as a biomarker in bladder cancer (BC). In the present pilot study, we used a platform originally developed for detection of breast cancer CTCs to assess breast cancer-associated transcripts in CTCs of patients with different stages of BC. Moreover, transcripts specific for cancer stem cells and epithelial mesenchymal transition (EMT) were assessed. METHODS: We prospectively enrolled 83 BC patients and 29 controls. The AdnaTest® system was used to enrich epithelial cells in peripheral blood and to detect breast cancer-associated, stem cell-specific or EMT-specific transcripts. Test results were correlated with clinical and pathological stage. RESULTS: A positive AdnaTest® BreastCancerDetect was present in 6.9 % of controls (group A), 6.7, 15.0 and 18.7 % of patients with non-muscle-invasive BC (B), cM0 muscle-invasive BC (C) and metastatic BC (D) (p = 0.13). Stem cell-specific transcripts in group A, B, C and D were detected in 10.3, 10.0, 22.5 and 31.3 % (p = 0.03). EMT-associated transcripts were present in 3.5, 3.3, 15.0 and 18.7 % (p = 0.03). In group C, epithelial and stem-like transcripts correlated with tumor stage (p = 0.01 and 0.04). CONCLUSIONS: CTCs with expression of breast cancer-associated transcripts are present in a considerable proportion of patients with BC. EMT and stem cell-specific transcripts of CTCs correlate with clinical stage and can be detected in patients negative for epithelial transcripts. The prognostic relevance of AdnaTest® results in BC patients and potential implications for therapy decisions remain to be determined in prospective studies.

Prostate tumor overexpressed 1 expression in invasive urothelial carcinoma.

PURPOSE: To determine the expression patterns of the proliferation marker prostate tumor overexpressed 1 (PTOV1) in invasive urothelial cancer (UC). METHODS: Corresponding UC and benign samples from paraffin-embedded tissue of 102 patients treated with cystectomy for invasive UC were immunohistochemically (IHC) assessed for PTOV1. Expression was evaluated gradually separated for cytoplasmic and nuclear staining. Results were correlated to histological and clinical data. To correlate PTOV1 expression with molecular subtypes of UC, analysis of PTOV1 RNA expression data of the Cancer Genome Atlas UC cohort was performed. RESULTS: PTOV1 expression was present in UC and benign urothelium, whereby nuclear staining was significantly more frequent in UC tissue (p = 0.0004). Lower cytoplasmic expression was significantly associated with pathological stage >pT2 (p = 0.0014) and grade ≥G3 (p = 0.0041), respectively. IHC expression patterns did not show correlation to survival data. PTOV1 RNA expression correlated with features of the luminal UC subtype. CONCLUSIONS: Subcellular distribution seems to be the most important feature of PTOV1 expression in UC. Nuclear localization of PTOV1 along with cytoplasmic decrease in PTOV1 expression was identified as putative surrogate for PTOV1-associated cellular proliferation and dedifferentiation in UC. The functional relevance as well as the potential role of PTOV1 as a biomarker in UC remains to be specified in future studies.

Expression patterns and prognostic role of transketolase-like 1 in muscle-invasive bladder cancer.

PURPOSE: The pentose phosphate pathway (PPP) has been shown to play an important role in the metabolism of cancer cells. The transketolase-like 1 gene (TKTL1) encodes an enzyme representing an essential component of this pathway. Its expression has been demonstrated to correlate with stage and outcome in various tumors. The aim of the present study was to assess expression patterns and the prognostic role of TKTL1 in muscle-invasive bladder cancer (MIBC). PATIENTS AND METHODS: The expression of TKTL1 was assessed in a tissue microarray consisting of histopathologically benign and malign tissue of 112 patients who underwent radical cystectomy due to MIBC. Cytoplasmatic and nuclear expression were assessed by immunohistochemistry and compared separately with clinicopathologic parameters and outcome. RESULTS: Cytoplasmatic expression of TKTL1 was exclusively present in tumor tissue. In contrast, the proportion of nuclei positive for TKTL1 was higher in histopathologically benign tissue compared with malign tissue. No correlation was observed between cytoplasmatic or nuclear TKTL1 expression and tumor stage, grade or the presence of metastases. Patients with lymph node involvement showed a decreased frequency of cytoplasmatic expression compared with node-negative patients (p = 0.01). However, no further correlation was observed between the expression of TKTL1 and clinical outcome of patients. CONCLUSIONS: The present study shows that the cytoplasmatic expression of TKTL1 is specific for MIBC tissue compared with histopathologically benign urothelium. This specific expression is present in a subgroup of MIBC potentially identifying patients with activated PPP suitable for a targeted inhibition of sugar metabolism. In contrast to other malignancies, TKTL1 shows no prognostic significance in MIBC.

Significance of apoptotic and non-apoptotic disseminated tumor cells in the bone marrow of patients with clinically localized prostate cancer.

BACKGROUND: Disseminated tumor cells (DTC) can be detected in a high proportion of patients with localized solid malignancies. In prostate cancer (PC), determination of DTCs is critically discussed as there are conflicting results on their prognostic value. The aim of the present study was to evaluate the presence and prognostic role of DTCs in PC patients with a high risk of disease recurrence. METHODS: 248 patients with clinically localized PC undergoing radical prostatectomy with features of increased risk of recurrence (PSA ≥10 ng/ml or Gleason score ≥ 4 + 3 = 7 or pT ≥3) were included. All patients underwent intraoperative bone marrow (BM) aspiration biopsy. BM cells were evaluated by immunocytochemistry for cytokeratines and the apoptosis marker caspase-cleaved cytokeratin 18 (M30). Results of immunocytochemistry were correlated with clinical and pathological parameters and clinical outcome of the patients. RESULTS: Of 248 patients, 47 (19.0%) had evidence of DTCs at time of radical prostatectomy. In 17 of these 47 patients (36.2%), DTCs expressed the apoptosis marker M30. We observed no correlation between the presence of DTCs and tumor stage, nodal stage, prostate-specific antigen, or Gleason score. After a median-follow-up of 58 months (23-76), no differences in rates of biochemical recurrence, development of metastases and cancer-specific death were observed between patients with and without DTCs while apoptosis markers had no role. CONCLUSIONS: In a single-centre cohort of patients with increased risk for disease recurrence, the presence of DTCs at the time of prostatectomy does not influence clinical outcome. For the first time in patients with PC, DTCs were evaluated for immunocytological features indicating apoptosis. Due to conflicting results of studies on DTCs, BM biopsies at time of radical prostatectomy cannot be recommended as a standard procedure in patients with clinically localized PC.

Serum receptor activator of nuclear factor κB ligand (RANKL) levels predict biochemical recurrence in patients undergoing radical prostatectomy.

UNLABELLED: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: There is increasing evidence that the receptor activator of nuclear factor κB ligand (RANKL) pathway not only contributes to the development of bone metastases, but also influences tumour biology in earlier stages of cancer. The study shows that preoperative serum levels of RANKL and its inhibitor osteoprotegerin (OPG) have a prognostic impact in patients undergoing radical prostatectomy for clinically localized prostate cancer. Both high levels of RANKL and a higher RANKL/OPG ratio are independent predictors of early biochemical recurrence in these patients. OBJECTIVE: To assess the prognostic impact of proteins of the receptor activator of nuclear factor κB (RANKL) pathway in serum samples from patients undergoing radical prostatectomy. PATIENTS AND METHODS: We retrospectively determined soluble RANKL (sRANKL) and osteoprotegerin (OPG) by ELISA in serum samples of 178 patients undergoing radical prostatectomy between 2004 and 2006. Clinical and patient follow-up data were analysed using the Wilcoxon-Mann-Whitney test, the Kaplan-Maier method, and single variable or multifactorial Cox proportional hazards analysis. RESULTS: Higher serum sRANKL levels (P = 0.01), lower serum OPG levels (P = 0.01) and a higher sRANKL/OPG ratio (P = 0.004) were significant risk factors for biochemical recurrence (BCR). In multifactorial analysis, adjusted for the common risk factors for BCR, sRANKL and sRANKL/OPG ratio were confirmed as independent prognostic factors. Neither sRANKL nor OPG showed a clear association with histopathological factors such as pT stage, pN Gleason score or resection margin status, nor were they associated with prostate-specific antigen level. CONCLUSIONS: Greater activity of the RANKL pathway in the serum of patients with prostate cancer undergoing radical prostatectomy is a risk factor for BCR. The RANKL pathway seems to contribute to the biological behaviour of prostate cancer even at the organ-confined stage of the disease.

Evaluation of a new quantitative point-of-care test platform for urine-based detection of bladder cancer.

OBJECTIVE: Several commercial point-of-care (POC) tests are available for urine-based detection of bladder cancer (BC). However, these tests are restricted to dichotomized results (positive or negative), which limits their diagnostic value. Quantitative protein-based tests offer improved risk stratification but require complex methods restricted to specialized centers. Recently, the first quantitative POC system based on the detection of cytokeratin fragments became available. The aim of the study was to evaluate the diagnostic accuracy of this quantitative POC test. PATIENTS AND METHODS: A total of 198 patients having symptoms suspicious for BC were included. All patients received urethrocystoscopy and upper-tract imaging. Urine samples were analyzed by the urine BC antigen (UBC) rapid POC system and evaluated both visually and quantitatively using the concile Omega 100 POC reader. For visual evaluation, different thresholds of band intensity for considering a test positive were applied. Moreover, the UBC enzyme-linked immunosorbent assay (ELISA), urine cytology, and the nuclear matrix protein 22 BladderChek were performed. Sensitivities and specifities were calculated by contingency analyses. Optimal cutoffs of quantitative tests were determined by receiver operating characteristic curves. RESULTS: A total of 61 patients (30.8%) were diagnosed with BC. Visual evaluation of the UBC revealed sensitivities of 38.1% to 71.4% with corresponding specificities of 54.1% to 89.1%, dependent on the threshold of band intensity applied. The quantitative UBC rapid showed a sensitivity of 60.7% and a specificity of 70.1% at optimal cutoff (area under the curve = 0.68). A constant increase of both the probability of BC and high-risk BC with increasing UBC rapid values was observed. UBC concentrations determined by the reader significantly correlated with the UBC ELISA (P<0.001). The UBC ELISA, the nuclear matrix protein22 BladderChek and cytology showed sensitivities of 48.3%, 16.4%, and 51.7% with specificities of 71.3%, 95.3%, and 78.1%, respectively. CONCLUSION: The UBC rapid in combination with a quantitative POC-reader system for the first time enables quantitative determination of a BC marker under POC conditions. Diagnostic accuracy is at least equivalent to elaborate ELISA-based measurement. The quantitative use of the UBC rapid test facilitates risk prediction compared with conventional nonquantitative dichotomized POC testing.

Altered expression of farnesyl pyrophosphate synthase in prostate cancer: evidence for a role of the mevalonate pathway in disease progression?

BACKGROUND: Preclinical studies demonstrated effects of drugs inhibiting the mevalonate pathway including nitrogen-containing bisphosphonates (N-BPs) and statins on tumor growth and progression. The exact role of this pathway in prostate cancer (PC) has not been identified yet. Herein, we evaluate the expression of farnesyl pyrophosphate synthase (FPPS), the key enzyme of the mevalonate pathway, in PC. PATIENTS AND METHODS: Prostate cancer (PC) and benign prostate tissue of 114 men who underwent radical prostatectomy were constructed to a tissue microarray. Immunohistochemical staining of FPPS was quantified by the Remmele/Stegner immunoreactivity-score. Patients' clinical follow-up was assessed. IRS was correlated to pathological and clinical data. The impact of FPPS expression on clinical course was assessed univariate and multivariate. RESULTS: Mean IRS in PC and benign tissue was 5.7 (95% CI 5.0-6.5) and 2.6 (2.1-3.0, p < 0.0001). Mean IRS in PC tissue of patients with organ-confined and locally advanced disease (pT ≥ 3) was 5.09 (4.22-5.96) and 6.87 (5.57-8.17, p = 0.035). IRS of PC tissue significantly correlated with Gleason score (p = 0.03). Patients with PC tissue IRS >3 showed shorter recurrence-free survival compared to the remaining (p = 0.01). Increased FPPS expression is an independent risk factor for early biochemical recurrence (p = 0.032). CONCLUSIONS: This is the first study on FPPS in PC specimens. The association of FPPS with established histopathological risk parameters and biochemical recurrence implicates a contribution of the mevalonate pathway to PC progression. Further functional analysis is required to explore the role of this pathway in PC and to investigate whether FPPS expression affects the response of PC cells to N-BPs.

Individual risk assessment in bladder cancer patients based on a multi-marker panel.

PURPOSE: To investigate whether a combined application of urine cytology (CYT) and molecular markers for bladder cancer (BC) can predict tumor aggressiveness. METHODS: The study comprised 2,113 patients who underwent urethrocystoscopy and transurethral resection of the bladder. CYT, fluorescence in situ hybridization (FISH), immunocytology (uCyt+) and nuclear matrix protein 22 test (NMP22-ELISA) were performed. Results of the individual tests and of a multi-marker panel were correlated with pT-stages and tumor grades. RESULTS: Five hundred and two of 2,113 (23.8 %) patients had BC. False-negative test rates of CYT (p < 0.001), FISH (p = 0.01) and NMP22-ELISA (p = 0.05) were lower in patients with muscle-invasive BC compared with patients with non-muscle-invasive BC. Furthermore, false-negative rates of CYT (p < 0.001), FISH (p = 0.0002) and NMP22-ELISA (p < 0.001) were lower in patients with G3/CIS compared with patients with G1-G2 BC. In patients with evidence of tumor in urethrocystoscopy, the presence of simultaneously positive CYT and NMP22 was associated with a 20-fold risk for G3/CIS (p < 0.0001). CONCLUSIONS: This is the first study investigating the combined use of four urine markers in addition to cystoscopy to predict tumor aggressiveness. Our results indicate that combined application of urine markers as an adjunct to cystoscopy may facilitate identification of patients harboring high-grade tumors.

Alterations of the RANKL pathway in blood and bone marrow samples of prostate cancer patients without bone metastases.

OBJECTIVES: The receptor activator of the NF-kB ligand (RANKL) pathway is a key mediator of prostate cancer (PC)-induced bone disease. However, little is known about this pathway in patients with non-metastatic PC. We aimed to investigate whether changes of RANKL, its inhibitor osteoprotegerin (OPG) and bone marrow-mesenchymal stromal cells (BM-MSCs) occur in PC patients without manifest bone metastases. PATIENTS AND METHODS: We determined OPG and soluble RANKL (sRANKL) in serum and corresponding bone marrow (BM) samples of 140 patients before radical prostatectomy by enzyme-linked immunosorbent assay (ELISA). As control serum samples of 50 patients with benign prostate hyperplasia were analyzed. BM mononuclear cells (BMNCs) of 16 PC patients were analyzed for expression of RANKL and CD271 (as marker for MSCs) by flow cytometry. RESULTS: PC patients had significantly lower serum levels of OPG compared to BPH patients (P = 0.007), whereas no differences were observed for serum sRANKL (P = 0.74). Both OPG and sRANKL concentrations of serum and corresponding BM samples correlated significantly (P < 0.0001 each). Interestingly, in PC patients, lower serum and BM OPG levels were associated with a higher proportion of BM-MSCs (P = 0.04 and 0.0016, respectively). No correlations were observed for sRANKL, OPG, BM-MSCs, and established risk parameters of PC. DISCUSSION: The results of the study indicate that localized PC is associated with early specific changes of the RANKL pathway in serum and bone marrow (BM). These changes might be part of the pre-metastatic niche of PC and implicate a potential benefit of RANKL inhibition in patients with localized PC.

Insulin receptor isoforms A and B as well as insulin receptor substrates-1 and -2 are differentially expressed in prostate cancer.

AIMS/HYPOTHESIS: In different cancers types, insulin receptor isoform composition or insulin receptor substrate (IRS) isoforms are different to healthy tissue. This may be a molecular link to increased cancer risk in diabetes and obesity. Since this is yet unclear for prostate cancer, we investigated IR isoform composition and IRS balance in prostate cancer compared to benign and tumor adjacent benign prostate tissue and brought this into relation to cell proliferation. METHODS: We studied 23 benign prostate samples from radical cystectomy or benign prostatic hyperplasia surgery, 30 samples from benign tissue directly adjacent to prostate cancer foci and 35 cancer samples from different patients. RNA expression levels for insulin receptor isoforms A and B, IRS-1, IRS-2, and IGF-1 receptor were assessed by quantitative real-time RT-PCR. In addition, RNA- and protein expression of the cell cycle regulator p27(Kip1) was quantified by real-time RT-PCR and immunohistochemistry. RESULTS: Insulin receptor isoform A to B ratio was significantly higher in cancer as well as in tumor adjacent benign prostate tissue compared to purely benign prostates (p<0.05). IRS-1 to IRS-2 ratios were lower in malignant than in benign prostatic tissue (p<0.05). These altered ratios both in cancer and adjacent tissue were significantly associated with reduced p27(Kip1) content (p<0.02). Interestingly, IGF-1 receptor levels were significantly lower in patients with type 2 diabetes (p = 0.0019). CONCLUSIONS/INTERPRETATION: We found significant differences in the insulin signaling cascade between benign prostate tissue and prostate cancer. Histological benign tissue adjacent to cancer showed expression patterns similar to the malignancies. Our findings suggest a role of the insulin signaling pathway in prostate cancer and surrounding tissue and can hence be relevant for both novel diagnostic and therapeutic approaches in this malignancy.

Preliminary experience on the use of the Adnatest® system for detection of circulating tumor cells in prostate cancer patients.

BACKGROUND: The Adnatest® system combines immunomagnetic enrichment of epithelial cells with polymerase chain reaction for prostate cancer (PC)-specific transcripts for the detection circulating tumor cells (CTCs). We evaluated the Adnatest® in patients with castration-resistant PC receiving docetaxel chemotherapy. PATIENTS AND METHODS: CTCs were assessed in 16 patients with castration-resistant PC before cycles one and three of chemotherapy. Furthermore, markers of stem cells and epithelial-mesenchymal transition were assessed. Treatment response was assessed by imaging and prostate-specific antigen measurements. RESULTS: Before chemotherapy, 11 patients were Adnatest®-positive whereas five patients were Adnatest®-positive before cycle three. A positive Adnatest® correlated with radiological progression (p=0.02). Rates of disease progression in epidermal growth factor receptor (EGFR)-positive and -negative patients were 100% and 7.7% (p=0.03). CONCLUSION: In this preliminary study, the Adnatest® detected CTCs in a considerable proportion of patients with castration-resistant PC. First data on certain markers (EGFR and aldehyd dehydrogenase 1) encourage future studies investigating transcripts predicting treatment response.

Influence of urinary tract instrumentation and inflammation on the performance of urine markers for the detection of bladder cancer.

OBJECTIVE: To evaluate the impact of inflammation and sampling on cytology, immunocytology, and fluorescence in situ hybridization (FISH) in comparison with NMP22 in hematuria patients. The specificity of urine markers for urothelial cancer is subject to exogenous factors. There is evidence that nuclear matrix protein 22 (NMP22) is influenced by urinary tract infection and instrumented urinary sampling (IUS). METHODS: Samples from 1386 patients with histologic work-up were included. Cytology, immunocytology, FISH, and NMP22-enzyme-linked immunosorbent assay were performed. The presence of inflammation was evaluated by microscopy. The method of urine sampling was recorded in all cases. Any type of urinary tract manipulation was considered as IUS. False-positive results were compared with regard to the presence or absence of inflammation and mechanical manipulation. RESULTS: In all, 1050 (75.7%) patients had no evidence of urothelial cancer. NMP22 results were false positive in 74.3% and 38.4% of patients with and without IUS (P < .0001). False-positive test rates of cytology, immunocytology, and FISH were not increased after manipulation. Inflammation led to a rise in false-positive NMP22 test results (85.3% vs 61.4%, P < .0001). The presence of inflammation did not change the rate of false-positive cytology, immunocytology, and FISH results. CONCLUSION: This is the first study to investigate the impact of inflammation and IUS on cell-based urine markers. In contrast to the protein test NMP22, these factors did not impair the performance of cell-based tests. Hence, patients with positive cytology, immunocytology, and FISH results should undergo diagnostic work-up, even in the case of concomitant inflammation or IUS.

Activation of the PKB/Akt pathway in histological benign prostatic tissue adjacent to the primary malignant lesions.

In order to evaluate the molecular heterogeneity of prostate cancer, this study examined the expression of Akt-pathway related parameters within the cancerous prostate gland. PTEN, p-Akt and p27kip1 are known to be altered in prostate cancer. Tissue samples from malignant, tumor adjacent benign and benign areas of 25 whole mounted prostate cancer specimens were processed to 583 tissue microarray cores. Immunohistochemically determined biomarker expression was correlated to the different localizations. p-Akt and p27kip1 showed increased staining in malignant tissue compared to the respective benign tissue (p < 0.01 and p < 0.05). The adjacent but histologically benign tissue had increased levels (p < 0.05 and p < 0.01), whereas no significant difference was found between the adjacent and malignant regions. A highly significant correlation of p-Akt and p27kip1 in benign tissue (p < 0.001) was lost in the adjacent areas and in the malignant tissue (p = 0.054 and p = 0.12). In tendency, PTEN expression was decreased in the malignant regions and revealed the highest staining in the adjacent zone. According to the results obtained, the expression of p-Akt and p27kip1 was increased in both the adjacent microscopically benign tissue as well as the primary tumors when compared with the histologically benign tissue specimens that served as biological control. The increased expression of PTEN indicates its regulatory function in the initial steps of a deteriorated cell cycle control as well as uncontrolled cellular proliferation, for example, which seem to be present in the normal prostatic tissue surrounding the primary malignant lesion. The addition of molecular markers to a 'classical' histopathological approach might contribute to an enhanced sensitivity of analytical approaches aimed at the detection of malignant or premalignant lesions within prostatic biopsies.