Malignant Prostate Tissue Research Articles

MP48-02 FLUORESCENCE SPECTROSCOPY CAN INCREASE DIAGNOSTIC YIELD OF PROSTATE BIOPSIES

You have accessJournal of UrologyProstate Cancer: Detection and Screening I1 Apr 2015MP48-02 FLUORESCENCE SPECTROSCOPY CAN INCREASE DIAGNOSTIC YIELD OF PROSTATE BIOPSIES E. David Crawford, Edward A. Jasion, Yongjun Liu, John Daily, Paul Arangua, Clifford Jones, S. Russell Nash, and Priya Werahera E. David CrawfordE. David Crawford More articles by this author , Edward A. JasionEdward A. Jasion More articles by this author , Yongjun LiuYongjun Liu More articles by this author , John DailyJohn Daily More articles by this author , Paul AranguaPaul Arangua More articles by this author , Clifford JonesClifford Jones More articles by this author , S. Russell NashS. Russell Nash More articles by this author , and Priya WeraheraPriya Werahera More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1676AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Transrectal ultrasound (TRUS) guided prostate biopsy cores have a very low diagnostic yield as 90% cores are histopathologically classified as benign. We investigated potential clinical application fluorescence spectroscopy (FS) to increase diagnostic yield of TRUS biopsies. The fluorescence emissions from natural fluorophores (e.g., collagen) in prostate tissue are altered by the presence of prostate cancer (PCa). Thus, FS can be used to distinct malignant locations from benign to aid TRUS biopsies. METHODS 14G optical biopsy needle was prototyped to capture FS of prostate tissue. Integrated optical sensor uses 8x100 μm fibers for excitation and 1x200 μm fiber to collect FS data. Custom made fluorometers with 2 light-emitting diodes at 290 and 340 nm and a spectrometer were used to measure FS of prostate tissue. User interface for fluorometer operation and data collection was developed using LabView software. Each spectral data acquisition takes ∼250 milliseconds. The in vivo biopsies were performed during radical prostatectomy surgery on the exposed prostate with blood flow to the gland intact. A tissue biopsy core was obtained from each biopsy site after acquisition of FS data. Above procedure was repeated ex vivo after surgical excision of the prostate. Biopsy cores were histopathologically classified as benign or malignant and correlated with corresponding FS data. Partial Least Square analysis of the FS data was performed to determine principal components (PCs) at each excitation wavelength. Using linear support vector machine and leave-one-out cross validation method, several combinations of PCs were tested for their ability to classify benign vs. malignant prostatic tissue. RESULTS Thirteen patients were consented. A total of 208 in vivo biopsies (29 malignant) and 224 ex vivo biopsies (51 malignant) were analyzed. Results for benign vs. malignant prostatic tissue classification based on number of PCs used are given in the table. CONCLUSIONS Our optical biopsy needle assisted with FS has a very high NPV to indicate benign tissue while sufficient SE and SP for real-time diagnosis of PCa by targeting areas positive for cancer within the prostate gland. Hence, systematic use of optical biopsies can potentially increase diagnostic yield of prostate biopsies. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e594 Peer Review Report Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information E. David Crawford More articles by this author Edward A. Jasion More articles by this author Yongjun Liu More articles by this author John Daily More articles by this author Paul Arangua More articles by this author Clifford Jones More articles by this author S. Russell Nash More articles by this author Priya Werahera More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

173 Reduced autophagy levels are associated with a higher Gleason score, tumour stage and an increased rate of prostate cancer specific death

INTRODUCTION AND OBJECTIVES: Autophagy is a catabolic cellular process used for degradation of cytoplasmic organelles and preservation of cell viability. Data regarding the role of autophagy in treatment naive prostate cancer (PCa) is sparse. Therefore we aimed to analyze the level of autophagy in benign and malignant prostate tissue and to evaluate the prognostic properties for patients with PCa. METHODS: A Tissue microarray containing 479 formalin-fixed, paraffin-embedded prostate tissue cores was stained immunohistochemically for major autophagy proteins ATG5, Beclin1 and LC3b: 41 normal prostate tissues, 382 primary adenocarcinomas (ADC) and 56 prostate cancer metastases or castration resistant prostate cancers. Immunoreactivity was semiquantitatively scored and correlated with pathologic and clinical parameters including survival. RESULTS: LC3b expression was significantly upregulated in PCa, especially in metastatic and castration-resistant prostate cancer samples compared to normal prostate tissue (p1⁄40.002). Evaluation of expression in ADCs revealed an inverse association with preoperative serum PSA level (p1⁄40.047), pT-stage (0.033) and Gleason Score (p1⁄40.026). Negative LC3b expression was identified as a novel predictor of prostate cancer specific death after radical prostatectomy (p1⁄40.02). A significant association of ATG-5 and Beclin1 with LC3b expression could be noticed, but no link with clincopathologic parameters. CONCLUSIONS: A lower LC3b expression in prostate cancer tissue is significantly associated with a higher rate of prostate cancer specific death. Furthermore, there is a significant association of a lower expression in tumors with extraprostatic extension and higher Gleason Scores. This is the first report evaluating autophagy expression levels and their association with the clinical course in prostate cancer patients.

Structural Heterogenity of Intraluminal Content of The Prostate: A Histochemical and Ultrastructural Study

Intraluminal contents of benign and malignant prostatic tissue are associated with varying forms of acellular structures. These include corpora amylacea, prostatic calculi, and prostatic crystalloids. There are relatively few microscopy studies about the characterization of intraluminal structures from benign and malignant prostatic glands and little is known about their chemical composition. In the present study, we used a combination of special histochemical methods, immunohistochemistry, and transmission electron microscopy to characterize intraluminal contents of benign and malignant prostate glands. The study was done on 33 radical prostatectomy and four transurethral resections of prostate specimens. Histochemical methods such as von Kossa, autometallography (AMG), as well as PSA immunohistochemistry and transmission electron microscopy were performed to characterize intraluminal contents of benign and malignant prostate glands. Von Kossa staining was observed in acellular structures, corpora amylacea, prostatic calculi, and calcified blood vessels. AMG staining was observed in the lumen of small glands, in the epithelium lining prostate glands, and corpora amylacea. PSA staining showed prostatic glands with both positive and negative corpora amylacea and epithelial cells. Ultrastructural observation revealed the presence of a variety of highly heterogeneous aggregates composed of fibrillar elements that were similar to those of amyloid.

Expression of adenosine receptor subclasses in malignant and adjacent normal human prostate tissues.

Adenosine, a purine nucleoside plays important roles in the pathogenesis of cancer initiation and promotion via interaction with four adenosine receptors. In the present study we examined the differential expression pattern of adenosine receptors in the malignant and adjacent normal human prostate tissues. Prostate cancer tissue samples and adjacent normal tissues were obtained from 20 patients undergoing radical prostatectomy and histopathological diagnosis was confirmed for each sample. Total RNA was extracted and reverse transcribed into cDNA and the mRNA expression levels of adenosine receptors were investigated by Taq-man real-time RT-PCR experiment. Quantitative protein analysis was done by Western blotting experiment. Moreover, the mRNA and protein expression levels of adenosine receptors were measured after androgen treatment. Taq-man real-time RT-PCR measurements show different expression levels of adenosine receptor transcripts. A2B adenosine receptor was predominantly expressed in tumor tissues (2.4-fold) followed by significantly expression of A3 (1.6-fold) and A2A adenosine receptors (1.5-fold) compared to adjacent normal tissues. The presence of adenosine receptors at protein levels in prostate cancer tissues compared with normal tissues was shown the following rank order: A2B > A3 > A2A > A1 . Androgen receptor regulates adenosine receptors mRNA and protein expression in AR-positive LNCaP cells, which was not seen in AR-negative PC-3 cells. These results indicated for the first time, the differential mRNA expression profile and protein levels of adenosine receptors in the human prostate cancer. Interestingly, the A2B adenosine receptor followed by A3 is highly expressed in prostate tumor samples in comparison with the adjacent normal tissues. The findings support the possible key role of A2B adenosine receptor in promoting cancer cell growth and suggest that A2B may be a novel target for prostate cancer treatment.

Dosimetry and first clinical evaluation of the new 18F-radiolabeled bombesin analogue BAY 864367 in patients with prostate cancer.

The aim of this first-in-man study was to demonstrate the feasibility, safety, and tolerability, as well as provide dosimetric data and evaluate the imaging properties, of the bombesin analogue BAY 864367 for PET/CT in a small group of patients with primary and recurrent prostate cancer (PCa). Ten patients with biopsy-proven PCa (5 with primary PCa and 5 with prostate-specific antigen recurrence after radical prostatectomy) were prospectively selected for this exploratory clinical trial with BAY 864367, a new (18)F-labeled bombesin analogue. PET scans were assessed at 6 time points, up to 110 min after intravenous administration of 302 ± 11 MBq of BAY 864367. Imaging results were compared with (18)F-fluorocholine PET/CT scans. Dosimetry was calculated using the OLINDA/EXM software. Three of 5 patients with primary disease showed positive tumor delineation in the prostate, and 2 of 5 patients with biochemical relapse showed a lesion suggestive of recurrence on the BAY 864367 scan. Tumor-to-background ratio averaged 12.9 ± 7.0. The ratio of malignant prostate tissue to normal prostate tissue was 4.4 ± 0.6 in 3 patients with tracer uptake in the primary PCa. Mean effective dose was 4.3 ± 0.3 mSv/patient (range, 3.7-4.9 mSv). BAY 864367, a novel (18)F-labeled bombesin tracer, was successfully investigated in a first-in-man clinical trial of PCa and showed favorable dosimetric values. Additionally, the application was safe and well tolerated. The tracer delineated tumors in a subset of patients, demonstrating the potential of gastrin-releasing-peptide receptor imaging.

Intratherapeutic biokinetic measurements, dosimetry parameter estimates, and monitoring of treatment efficacy using cerenkov luminescence imaging in preclinical radionuclide therapy.

In recent years, there has been increasing interest in noninvasive Cerenkov luminescence imaging (CLI) of in vivo radionuclide distribution in small animals, a method proven to be a high-throughput modality for confirmation of tracer uptake. 11B6 is an IgG1 monoclonal antibody that is specific to free human kallikrein-related peptidase 2, an antigen abundant in malignant prostatic tissue. Free human kallikrein-related peptidase 2 was targeted in prostate cancer xenografts using (177)Lu-labeled 11B6 in either murine or humanized forms for radionuclide therapy. In this setting, CLI was investigated as a tool for providing parameters of dosimetric importance during radionuclide therapy. First, longitudinal imaging of biokinetics using CLI and SPECT was compared. Second, the CLI signal was correlated to quantitative ex vivo tumor activity measurements. Finally, CLI was used to monitor the radionuclide treatment, and the integrated CLI radiance was found to correlate well with subject-specific tumor volume reduction. 11B6 was radiolabeled with (177)Lu through the CHX-A″-DTPA chelator. In vivo CLI and SPECT imaging of (177)Lu-DTPA-11B6 uptake was performed on NMRI and BALB/c nude mice with subcutaneous LNCaP xenografts up to 14 d after injection. Tumor size was measured to assess response to radionuclide therapy. CLI correlated well with SPECT imaging and could be applied up to 14 d after injection of 20 MBq with the specific tracer used. Through integration of the CLI radiance as a function of time, a dose metric for the tumors could be formed that correlated exponentially with tumor volume reduction. CLI provided valuable intratherapeutic biokinetic measurements for treatment monitoring and could be used as a tool for subject-specific absorbed dose estimation.

Identification and diagnostic performance of a small RNA within the PCA3 and BMCC1 gene locus that potentially targets mRNA.

PCA3 is a long noncoding RNA (lncRNA) with unknown function, upregulated in prostate cancer. LncRNAs may be processed into smaller active species. We hypothesized this for PCA3. We computed feasible RNA hairpins within the BMCC1 gene (encompassing PCA3) and searched a prostate transcriptome for these. We measured expression using qRT-PCR in three cohorts of prostate cancer tissues (n = 60), exfoliated urinary cells (n = 484 with cancer and n = 166 controls), and in cell lines (n = 22). We used in silico predictions and RNA knockup to identify potential mRNA targets of short transcribed RNAs. We predicted 13 hairpins, of which PCA3-shRNA2 was most abundant within the prostate transcriptome. PCA3-shRNA2 is located within intron 1 of PCA3 and appears regulated by androgens. Expression of PCA3-shRNA2 was upregulated in malignant prostatic tissues, exfoliated urinary cells from men with prostate cancer (13-273 fold change; t test P < 0.003), and closely correlated to PCA3 expression (r = 0.84-0.93; P < 0.001). Urinary PCA3-shRNA2 (C-index, 0.75-0.81) and PCA3 (C-index, 0.78) could predict the presence of cancer in most men. PCA3-shRNA2 knockup altered the expression of predicted target mRNAs, including COPS2, SOX11, WDR48, TEAD1, and Noggin. PCA3-shRNA2 expression was negatively correlated with COPS2 in patient samples (r = -0.32; P < 0.001). We identified a short RNA within PCA3, whose expression is correlated to PCA3, which may target mRNAs implicated in prostate biology. This short RNA is stable ex vivo, suggesting a role as a robust biomarker. We identify cytoplasmic enrichment of this RNA and potential targeting of mRNAs implicated in prostate carcinogenesis.

Expression of Peroxisome Proliferator Activated Receptor gamma in Prostatic Adenocarcinoma.

Peroxisome proliferator-activated receptor gamma (PPAR-γ), a ligand-activated transcription factor has been investigated as the target for cancer treatment as well as metabolic disorders. Recent studies have demonstrated that PPAR-γ ligands are anti-tumorigenic in prostate cancer due to anti-proliferative and pro-differentiation effects. The aim of this study was to validate PPAR-γ expression in malignant and benign prostate tissues by immunohistochemistry and quantitative real-time polymerase chain reaction (PCR). A total of 730 prostatic adenocarcinomas (PCAs) including 63 whole sections from radical prostatectomy specimens and tissue microarrays containing 667 PCAs were subject to immunostaining for two PPAR-γ antibodies. Twenty-five benign prostate tissues and PCAs were selected for investigating mRNA expression by quantitative real-time PCR. 10.7% of PCAs (78/730) showed cytoplasmic immunoreactivity of PPAR-γ and no nuclear immunoreactivity was noted in PCAs. Most benign prostatic glands showed negative immunoreactivity of PPAR-γ except for variable weak cytoplasmic staining in some glands. Nuclear immunoreactivity of PPAR-γ was noted some central zone and verumontanum mucosal epithelium. The constitutive PPAR-γ mRNA showed significantly lower level in PCAs compared to that in the benign tissues. There was no difference of PPAR-γ mRNA expression between low (≤7) and high (>7) Gleason score groups. There was no association of PPAR-γ mRNA level or cytoplasmic immunostaining with Gleason grade or pathologic stage. Our study supported the evidence of extra-nuclear localization and nongenomic actions of PPAR-γ. Further studies are needed to assess the functional role of PPAR-γ and to validate its therapeutic implication in prostate cancer.

Contribution of Stem Cells to Benign and Malignant Canine Prostate Tissues

Contribution of Stem Cells to Benign and Malignant Canine Prostate Tissues

Androgen-targeted therapy-induced epithelial mesenchymal plasticity and neuroendocrine transdifferentiation in prostate cancer: an opportunity for intervention.

Androgens regulate biological pathways to promote proliferation, differentiation, and survival of benign and malignant prostate tissue. Androgen receptor (AR) targeted therapies exploit this dependence and are used in advanced prostate cancer to control disease progression. Contemporary treatment regimens involve sequential use of inhibitors of androgen synthesis or AR function. Although targeting the androgen axis has clear therapeutic benefit, its effectiveness is temporary, as prostate tumor cells adapt to survive and grow. The removal of androgens (androgen deprivation) has been shown to activate both epithelial-to-mesenchymal transition (EMT) and neuroendocrine transdifferentiation (NEtD) programs. EMT has established roles in promoting biological phenotypes associated with tumor progression (migration/invasion, tumor cell survival, cancer stem cell-like properties, resistance to radiation and chemotherapy) in multiple human cancer types. NEtD in prostate cancer is associated with resistance to therapy, visceral metastasis, and aggressive disease. Thus, activation of these programs via inhibition of the androgen axis provides a mechanism by which tumor cells can adapt to promote disease recurrence and progression. Brachyury, Axl, MEK, and Aurora kinase A are molecular drivers of these programs, and inhibitors are currently in clinical trials to determine therapeutic applications. Understanding tumor cell plasticity will be important in further defining the rational use of androgen-targeted therapies clinically and provides an opportunity for intervention to prolong survival of men with metastatic prostate cancer.

Abstract C70: ABCD3 expression in prostate and breast tumors

Abstract Background: In a previous study, we identified the ABCD3 gene as important in aggressive prostate tumors. The ABCD3 gene is a member of the ABC (ATP-Binding Cassette) family. The ABC gene family give instructions for making transporter proteins that carry many types of molecules, such as fats, sugars, protein building blocks (amino acids) and drugs, across cell membranes and is known to play a role in chemoresistance is some cancers. Purpose: Little is known about role of ABCD3 in prostate cancer, hence in the present study we assessed the expression of ABCD3 in normal and malignant prostate tissue (without regard to racial ethnicity) and determined correlations between ABCD3 expression and clinicopathologic characteristics. Methods: Clinically annotated duplicate core tissue high-density prostate adenocarcinoma tissue microarray of 92 cases of adenocarcinoma, 2 prostate transitional cell carcinoma, 12 prostate adjacent normal tissue and 8 normal prostate tissue were stained with a monoclonal antibody against ABCD3 and scored for percentage of visible staining. Results: Increased ABCD3 expression correlated with increasing Gleason score (p=0.0094), age (p=0.0014) and pathology grade (p=0.0007). Interestingly, we also observed that ABCD3 expression was elevated to varying degrees in other types of cancers, breast (stage II a), brain, cervical, head and neck, kidney and pancreatic. Conclusions: We postulate that ABCD3 may be a putative prognostic biomarker that discriminates between indolent and aggressive cancers, albeit ABCD3 function in cancer progression is still under investigation. Citation Format: R. Renee Reams, Jacqueline D. Jones, Daniel Osborne, Honghe Wang, Clayton C. Yates, III. ABCD3 expression in prostate and breast tumors. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr C70. doi:10.1158/1538-7755.DISP13-C70

Canonical androstenedione reduction is the predominant source of signaling androgens in hormone-refractory prostate cancer.

It has been recognized for almost a decade that concentrations of signaling androgens sufficient to activate the androgen receptor are present in castration-resistant prostate cancer tissue. The source of these androgens is highly controversial, with three competing models proposed. We, therefore, wished to determine the androgenic potential of human benign and malignant (hormone-naïve and treated) prostate tissue when incubated with various precursors and examine concomitant changes in enzyme expression. Freshly harvested prostate tissue [benign, hormone-naïve, and hormone-refractory prostate cancer (HRPC)] was incubated in excess concentrations of cholesterol, progesterone, DHEA, androstenedione, or testosterone for 96 hours, and steroid concentrations in the conditioned media measured by gas chromatography-mass spectroscopy. Changes in the expression of androgen synthetic and/or degradative enzymes were determined by expression microarray and qPCR. Significant changes were confirmed in an independent dataset. Of the precursor molecules tested, only incubation with androstenedione gave rise to significant concentrations of signaling androgens. Although this was observed in all tissue types, it occurred to a significantly greater degree in hormone-refractory compared with hormone-naïve cancer. Consistent with this, gene set enrichment analysis of the expression microarray data revealed significant upregulation of 17HSD17B activity, with overexpression of the canonical enzyme AKR1C3 confirmed by qPCR in the same samples and in a publicly available expression dataset. Importantly, we found no evidence to support a significant contribution from either the "backdoor" or "5-α dione" pathway. Reduction of androstenedione to testosterone by the canonical HSD17B AKR1C3 is the predominant source of signaling androgens in HRPC.

Abstract 2944: Decline in arylsulfatase B (N-acetylgalactosamine-4-sulfatase) leads to increased expression of the transmembrane glycoprotein GPNMB

Abstract The enzyme arylsulfatase B (ARSB; N-acetylgalactosamine-4-sulfatase), which removes 4-sulfate groups from chondroitin-4-sulfate (C4S) and dermatan sulfate, is reduced in malignant human epithelial breast, colonic, and prostate cells and tissues. Lower ARSB immunohistochemical scores have been associated with shorter intervals to recurrence in paired cases of prostate cancer and with propensity for metastasis in malignant colonic cells. The transmembrane glycoprotein GPNMB has been shown to be increased in malignant melanoma, glioblastoma multiforme, and mammary carcinoma, and is a target of antibody therapy in triple-negative breast cancers. In the ARSB-deficient mouse, cDNA microarray of prostate tissue demonstrated 9.53-fold increase in expression of GPNMB, compared to age- and gender- matched C57BL/6J wild-type controls. Measurements by ELISA of GPNMB protein in the ARSB-null mouse liver and prostate tissues showed significant increases, compared to C57BL/6J wild-type controls. In the liver of female ARSB-deficient mice, the gpnmb increased to 47.1 ± 5.7 ng/mg protein from 8.5 ± 1.2 ng/mg protein in the control mouse liver (n=5 in each group), and similar six-fold increases occurred in the male ARSB-null mouse liver. Prostate gpnmb increased more that three-fold, and serum levels in female and male null mice were significantly greater. When ARSB was silenced by siRNA in the normal human prostate stromal cell line (WPMY-1), GPNMB increased from 3.6 ± 0.3 ng/mg protein to 18.3 ± 1.1 ng/mg protein, and in the normal human prostate epithelial cell line (WPE1-NB14) from 4.8 ± 0.4 to 24.7 ± 1.6 ng/mg protein. Similarly in the human hepatic cell line, HepG2, GPNMB increased greater than five-fold. Decline in ARSB leads to increased chondroitin-4-sulfation and reduced galectin-3 binding to C4S, enabling increased nuclear translocation of galectin-3. We have shown that the increase in nuclear galectin-3 following decline in ARSB impacts on transcriptional events mediated by AP-1 in human epithelial cells, including increases in HIF-1α and versican. However, in the prostate stromal and epithelial cell lines, AP-1 inhibitors, including a c-Jun mimetic peptide and an oligonucleotide inhibitor of c-Fos DNA-binding, did not reduce the increase in GPNMB expression that followed ARSB silencing. Although the mechanism for the decline in GPNMB expression is unknown at this time, the findings support a critical role for ARSB in vital cell processes and suggest that ARSB may be useful as a therapeutic target in malignancy. Citation Format: Sumit Bhattacharyya, Leo Feferman, Joanne Kramer Tobacman. Decline in arylsulfatase B (N-acetylgalactosamine-4-sulfatase) leads to increased expression of the transmembrane glycoprotein GPNMB. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2944. doi:10.1158/1538-7445.AM2014-2944

Abstract 39: Expression of uPA-system members correlate with the clinico-pathological parameters of PCa patients

Abstract Background: Members of the urokinase-type plasminogen activator (uPA) system play an important role in tumor progression and angiogenesis in different human malignancies including breast, kidney, colon, stomach and prostate cancer (PCa). The objective of this study was to determine the mRNA expression and protein levels of uPA system components in tissue specimens and serum samples, respectively, from patients with PCa, and to assess their potential association with clinic-pathological parameters and overall survival (OS). Material and methods: mRNA levels of uPA, its receptor (uPAR) and its inhibitor type 1 (PAI-1) were analyzed in corresponding malignant and adjacent non-malignant prostate tissue specimens from 132 PCa patients. Relative mRNA expression levels were determined by quantitative PCR and normalized to the reference gene TATA-box-binding protein. Pre-operative serum samples from 81 of the 132 PCa patients and 36 patients with benign prostatic hyperplasia (BPH) were analyzed for antigen levels of uPA system members by ELISA. Results: mRNA levels of the uPA system components displayed significant correlations with each other in the tumor tissues (uPA vs. uPAR: rs = 0.550; uPA vs. PAI-1: rs = 0.552; uPAR vs. PAI-1: rs = 0.643; all P &amp;lt; 0.001). A significantly decreased uPA mRNA expression in PCa tissue compared to the corresponding non-malignant tissue specimens was detected (data not shown). High mRNA expression of uPA and PAI-1 was significantly associated with a high Gleason score (P = 0.001 and P = 0.007, respectively; Fig. 2). Antigen levels of uPA and soluble uPAR (suPAR) in serum correlated weakly, but significantly, with each other (rs = 0.382, P &amp;lt; 0.001). A significant association was found between elevated suPAR concentrations in serum and poor OS of PCa patients (P = 0.022, log rank test). In multivariate Cox's regression analysis (adj. for age, lymph node status, tumor stage and Gleason sum) a high suPAR level was associated with a 7.12-fold increased risk of death (P=0.027). Conclusion: The observed association of high suPAR levels with poor survival of PCa patients is consistent with published data on patients afflicted with other types of solid cancer and strongly suggests a general prognostic impact of uPAR antigen levels in serum of cancer patients. Citation Format: Omar Al-Janabi, Helge Taubert, Andrea Lohse-Fischer, Michael Fröhner, Sven Wach, Robert Stöhr, Bastian Keck, Max Burger, Wolf Wieland, Kati Erdmann, Manfred P. Wirth, Bernd Wullich, Gustavo Baretton, Viktor Magdolen, Matthias Kotzsch, Susanne Füssel. Expression of uPA-system members correlate with the clinico-pathological parameters of PCa patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 39. doi:10.1158/1538-7445.AM2014-39

Abstract 1124: ETS1 regulates epithelial-to-mesenchymal transition (EMT) in prostate cancer cells

Abstract Background: The transcription factor ETS1 is overexpressed in up to 70% of prostate tumors. Three ETS1 isoforms which arise due to alternative splicing have been reported, ETS1p51, ETS1p42 and ETS1p27, each with distinct transcriptional activator or repressor functions. Elevated ETS1 levels in prostate tumors are correlated with more rapid progression to castrate-resistant disease and a poor prognosis, while ETS1 overexpression in vitro is correlated with increased migration and invasion of prostate cancer cells. Aim: To characterise ETS1 isoform expression in prostate tumors and to determine the effects of ETS1 overexpression on the regulation of epithelial-to-mesenchymal transition (EMT). Methods: ETS1 isoform expression was characterised in 45 malignant prostate and adjacent non-malignant prostatic tissues using isoform-specific RT-qPCR and western blotting. Expression of genes encoding regulators of EMT was screened using a Human EMT PCR array (SABiosciences) in the human prostate cancer cell line, LNCaP that had been transiently transfected to overexpress ETS1p51. RT-qPCR and western blotting were used to confirm the ETS1-induced levels of differentially expressed genes/proteins and western blotting for phospho-SMAD2 (pSMAD2)/total SMAD2 (tSMAD2) was used to investigate activation of TGF-β signalling. Results: ETS1p51 was the predominant ETS1 isoform expressed in both the normal prostate and prostate tumors, with significantly decreased mRNA (p&amp;lt;0.001), but significantly elevated (p&amp;lt;0.05) protein levels in the majority of malignant tissues. ETS1p51 overexpression increased (&amp;gt;1.5 fold) levels of pro-EMT regulators including members of the WNT (WNT5B, β-catenin) and TGF-β (TGF-β1/2/3) signalling pathways. Phosphorylation of the TGF-β signalling intermediate, SMAD2 was increased and mRNA/protein levels of the EMT transcriptional regulators, TWIST1, SNAIL1, SLUG and ZEB1 were also elevated. In ETS1p51 overexpressing cells, expression of the mesenchymal marker vimentin was increased, while expression of the epithelial tight-junction molecule, Claudin-1 was decreased. Together with increased expression of effectors of migration and invasion (e.g. SPARC, MMP2/9), the findings indicate induction of an EMT programme. Conclusions: Levels of ETS1p51, the predominant ETS1 isoform expressed in the prostate are upregulated by post-transcriptional mechanisms in prostate tumors. Increased ETS1p51 expression promotes TGF-β signalling and EMT, processes that are likely to contribute to the accelerated disease progression and poorer outcomes associated with ETS1 overexpressing prostate tumors. Citation Format: Jamie J. Rodgers, Michael Epis, Ronald Cohen, Peter Leedman, Jennet Harvey, Marc Thomas, Jacqueline Bentel. ETS1 regulates epithelial-to-mesenchymal transition (EMT) in prostate cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1124. doi:10.1158/1538-7445.AM2014-1124

Effects of E/Z isomers of lycopene on experimental prostatic hyperplasia in mice

AimLycopene is a member of the carotenoid family and has strong anti-oxidant properties. Lycopene occurs in tomato-based food products primarily as an all-E isomer (80–97%),but its Z-isomers accounts for 79 to 88% of total lycopene in benign or malignant prostate tissues, while the specific biological functions of Z-isomers are still not clarified at present. This study was to examine the bioactive potency of Z-isomers on benign prostatic hyperplasia (BPH) in mice and to make a comparison of effective inhibition between Z-isomers and all-E isomer. MethodMice were divided into the Saline group, Vehicle control group and testosterone propionate induced BPH mice group (BPH model group, vehicle BPH model group, lycopene treated (5mg/kg and 2.5mg/kg), Z-isomers (57%) treated, Z-isomers (86%) treated, finasteride treated). The drugs were orally administered once a day consecutively for 30days. The inhibitory effects on BPH of all-E lycopene and Z-isomers were evaluated by prostatic index, prostatic acid phosphatase (PAP), estradiol, testosterone and dihydrotestosterone (DHT) levels in serum and histopathology examination. ResultsCompared with the BPH model group, E/Z isomers exhibited significant differences in prostatic index, PAP, estradiol, testosterone and DHT levels in serum and similar histological aspects observed in the mice of the control group. The present research also shows that Z-isomers may be more potent inhibitors than all-E isomers in BPH treatment.

Investigation of miR-21, miR-141, and miR-221 expression levels in prostate adenocarcinoma for associated risk of recurrence after radical prostatectomy.

MicroRNAs (miRNAs) are small non-coding RNAs that regulate a broad array of cellular and disease processes. Several miRNAs are differentially expressed in cancer and many are being considered as biomarkers for predicting clinical outcomes. Here we quantified the expression of three miRNAs, miR-21, miR-141, and miR-221, from prostate cancer surgical specimens and evaluated their association with disease recurrence after primary therapy. A pilot nested case-control study was designed from a large cohort of men who underwent radical prostatectomy between 1993 and 2001. Total RNA was extracted from malignant prostate tissue of 59 cases (recurrence) and 59 controls. Cases and controls were matched on age, race, pathologic stage, and grade. The relative expression of each miRNA was then determined for each sample by quantitative real-time RT-PCR. Conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) of recurrence for tertiles of miRNA expression. We noted block storage time effects and thus, used separate tertile cutpoints based on the controls by calendar year of prostatectomy. Lower miR-221 expression was associated with a higher risk of recurrence; the ORs were 3.21 for the lowest tertile and 2.63 for the middle tertile compared with the highest tertile of expression (P-trend = 0.02). This pattern was unchanged after multivariable adjustment (P-trend = 0.05). No statistically significant trends were observed for miR-21 or miR-141 after multivariable adjustment. Based on this small pilot study, men with localized prostate cancers with lower miR-221 expression may have a greater risk for recurrence after surgery.

Preclinical imaging of kallikrein-related peptidase 2 (hK2) in prostate cancer with a (111)In-radiolabelled monoclonal antibody, 11B6.

BackgroundProstate cancer is a leading cause of death in the male population of the western world. Human kallikrein-related peptidase 2 (hK2) is abundantly expressed in malignant prostatic tissue, and its gene, KLK2, is regulated by the androgen receptor. 11B6 is a murine IgG1 monoclonal antibody directed against free human hK2. In this study, we performed a preclinical evaluation of 111In-labelled 11B6 in mouse xenografts to investigate its potential in the clinical staging and assessment of metastatic prostate cancer.Methods11B6 was radiolabelled with 111In through CHX-A″-DTPA chelation. In vivo biodistribution and uptake of 111In-DTPA-11B6 were measured until 168 h post-injection in NMRI nude mice bearing subcutaneous LNCaP xenografts. The binding specificity to hK2 was evaluated by both in vivo competitive binding assays with excess non-labelled 11B6 and hK2-negative DU145 xenografts. SPECT/CT imaging of subcutaneous and intra-tibial LNCaP xenografts was used to visualize the tumours.ResultsTumour uptake of 111In-DTPA-11B6 in LNCaP xenografts was 19% ± 0.78%IA/g at 48 h, giving a tumour-to-blood ratio of 1.6, which increases to 2.4 at 1 week post-injection. Accumulation was low in other organs except for the salivary glands, which is probably the result of cross-reactivity with mouse kallikreins. Significantly lower tumour accumulation was observed in competitive assays and DU145 xenografts. SPECT/CT imaging could clearly visualize the subcutaneous and intra-tibial LNCaP xenografts.ConclusionsOur study demonstrates the potential of 111In-DTPA-11B6 for the detection of metastatic prostate cancer and monitoring anti-androgen therapy, as it exhibits an increased uptake and accumulation in viable tumour when compared to normal tissue. A humanised version of the 11B6 monoclonal antibody is currently under evaluation.Electronic supplementary materialThe online version of this article (doi:10.1186/s13550-014-0051-5) contains supplementary material, which is available to authorized users.

The Cistrome and Gene Signature of Androgen Receptor Splice Variants in Castration Resistant Prostate Cancer Cells

Spliced variant forms of androgen receptor were recently identified in castration resistant prostate cancer cell lines and clinical samples. We identified the cistrome and gene signature of androgen receptor splice variants in castration resistant prostate cancer cell lines and determined the clinical significance of androgen receptor splice variant regulated genes. The castration resistant prostate cancer cell line 22Rv1, which expresses full-length androgen receptor and androgen receptor splice variants endogenously, was used as the research model. We established 22Rv1-ARFL(-)/ARV(+) and 22Rv1-ARFL(-)/ARV(-) through RNA interference. Chromatin immunoprecipitation coupled with next generation sequencing and microarray techniques were used to identify the cistrome and gene expression profiles of androgen receptor splice variants in the absence of androgen. Androgen receptor splice variant binding sites were identified in 22Rv1-ARFL(-)/ARV(+). A gene set was regulated uniquely by androgen receptor splice variants but not by full-length androgen receptor in the absence of androgen. Integrated analysis revealed that some genes were directly modulated by androgen receptor splice variants. Unsupervised clustering analysis showed that the androgen receptor splice variant gene signature differentiated benign from malignant prostate tissue as well as localized prostate cancer from metastatic castration resistant prostate cancer specimens. Some genes that were modulated uniquely by androgen receptor splice variants also correlated with histological grade and biochemical failure. Androgen receptor splice variants can bind to DNA independent of full-length androgen receptor in the absence of androgen and modulate a unique set of genes that is not regulated by full-length androgen receptor. The androgen receptor splice variant gene signature correlates with disease progression. It distinguishes primary cancer from castration resistant prostate cancer specimens and benign from malignant prostate specimens.

Systematic diagnosis of prostate cancer using an optical biopsy needle adjunct with fluorescence spectroscopy.

Transrectal ultrasound guided prostate biopsies often fail to diagnose prostate cancer with 90% of cores reported as benign. Thus, it is desirable to target prostate cancer lesions while reducing the sampling of benign tissue. The concentrations of natural fluorophores in prostate tissue fluctuate with disease states. Hence, fluorescence spectroscopy could be used to quantify these fluctuations to identify prostate cancer. An optical biopsy needle with a light sensitive optical probe at the tip of the inner needle was developed to take prostate biopsies after measuring tissue fluorescence with a laboratory fluorometer. The optical probe consists of eight 100 μm fibers for tissue excitation and a single 200 μm fiber to capture fluorescence spectra. Random biopsy cores were taken from 20 surgically excised prostates after measuring fluorescence spectra of tissue between 295-550nm for several excitations between 280-350nm. Each biopsy core was histopathologically classified and correlated with corresponding spectra. Prostate biopsies were grouped into benign or malignant based on the histological findings. Out of 187 biopsy cores, 109 were benign and 78 were malignant. Partial least square analysis of tissue spectra was performed to identify diagnostically significant principal components as potential classifiers. A linear support vector machine and leave-one-out cross validation method was employed for tissue classification. Study results show 86% sensitivity, 87% specificity, 90% negative predictive value, and 83% positive predictive value for benign versus malignant prostate tissue classification. This study demonstrates potential clinical applications of fluorescence spectroscopy guided optical biopsy needle for prostate cancer diagnosis with the consequent improvement of patient care.