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Objective: To determine the effects if cycling and rowing on serum prostate-specific antigen (PSA) levels., Methods: Male volunteers (n = 101), aged 20-80 (mean, 49.9) years were randomized to exercise at the first or second study visit. They performed 1 h of either cycling or rowing on a stationary machine. To determine exercise-induced effects on the PSA level, serum total PSA (tPSA) and free PSA (fPSA) concentrations were evaluated before and after exercise and another sampling was performed at the second study visit. Pre-exercise and postexercise tPSA and fPSA concentrations were compared using the Wilcoxon matched-pairs test. The results were analyzed using the Mann-Whitney U-test., Results: A significant (p < 0.001) average increase in tPSA after exercise (1.14 ± 1.11 ng/ml to 1.24 ± 1.26 ng/ml [mean, +8.8%]) was observed after both cycling and rowing, without significant differences between the sports (p = 0.54). The exercise-induced increase in PSA concentration affected participants aged ≥50 years (difference, 0.16 ± 0.37; p < 0.001), but not those aged <50 years (difference, 0.01 ± 0.06; p = 0.23). The effect size was clinically irrelevant in all except two outliers, in whom a distinct increase of PSA level by averages of 1.80 ng/ml (+55%) for tPSA and 1.25 ng/ml (+227%) for fPSA following cycling was observed., Conclusion: Rowing and cycling generally do not have a clinically relevant effect on PSA levels. However, outliers exist. Our findings do not support abstaining from exercise during the days approaching PSA sampling., (© 2022 Wiley Periodicals LLC.)

Background: Epithelial-to-mesenchymal transition (EMT) is involved in pathogenesis of human benign prostatic hyperplasia (BPH). Estrogenic signaling pathways may stimulate the induction of EMT. However, the details of estradiol (E2) and estrogen receptors (ERs) effects on EMT, as well as E2-induced modulation of benign prostatic epithelial cell phenotype in vitro have not been completely clarified., Methods: The effects of E2 on EMT markers and cytokeratins (CKs) expression were evaluated in benign epithelial cell lines BPH-1 and RWPE-1, which were cultured both in two-dimensional (2D) culture and three-dimensional (3D) culture model using hanging drop technique or 3D Matrigel model. ER antagonist, ICI182,780, was used to confirm the regulatory effects of E2 on EMT and phenotypic modulation. In 3D culture, immunohistochemical stainings were performed to detect the specific phenotype of cells that underwent EMT in acinar-like spheroids formed by RWPE-1. To illustrate the exact function of ERs in E2-induced EMT and phenotypic modulation, specific short interfering RNAs (siRNAs), and agonists were used to knockdown or activate individual ERs, respectively., Results: E2-induced EMT was observed both in 2D and 3D culture, with related regulation of EMT markers expression at both mRNA and protein level. In addition, E2 down-regulated luminal cell type markers CK18 and CK8 and up-regulated basal cell type markers CK5 and CK14. E2 also increased intermediate type markers CK15 and CK17, while it attenuated CK19 in 3D culture. ICI182,780 blocked E2-induced EMT and cell phenotypic switching. In 3D Matrigel culture, Vimentin was co-expressed with ERα and CK17, as well as with SMemb, which is related to cell status switching and proliferation. Knockdown of ERα but not GPR30 inhibited EMT, while ERβ knockdown facilitated EMT process. Knockdown of ERα blocked E2-induced EMT both in RWPE-1 and BPH-1. MRNA expression of EMT markers was stimulated by ERα-specific agonist PPT and inhibited by ERβ-specific agonist DPN., Conclusions: Estrogenic effect mediated by ERα can promote EMT. E2 is also an inductive factor of cell phenotypic switching. Cell type modulation is associated with E2-induced EMT in benign prostatic epithelial cells. Taken together the results support a contribution of estrogens to the pathogenesis of BPH in elderly men., (© 2017 Wiley Periodicals, Inc.)

Introduction and Objectives: Eotaxin-1 (CCL11) is a protein expressed in various tissues influencing immunoregulatory processes by acting as selective eosinophil chemo-attractant. In prostate cancer (PCa), the expression and functional role of CCL11 have not been intensively investigated so far. Therefore, the aim of the present study was to investigate the diagnostic or prognostic potential of Eotaxin-1 in PCa patients., Materials and Methods: We analyzed serum from 140 patients who have undergone prostate biopsy due to elevated prostate-specific antigen (PSA) levels as well as serum of 20 individuals with PSA levels < 1ng/ml (healthy control group). Moreover, 40 urine samples were analyzed. A custom-made Q-Plex array ELISA (Quansys Biosciences) for the detection of Eotaxin-1 was performed and Q-View Software used for quantification. In addition, clinical courses of patients documented in our Prostate Biobank database were analyzed. ROC and survival analyses were used to determine the diagnostic and prognostic power of Eotaxin-1 levels., Results: Serum Eotaxin-1 levels were significantly decreased in PCa (P = 0.006) as well as in benign prostate hyperplasia (P = 0.0006) compared to the control group. ROC analysis revealed that Eotaxin-1 is a significant marker to distinguish PCa from disease-free prostate. Moreover, we found that Eotaxin-1 expression is significantly decreased in Gleason score (GS) 6 (P = 0.0135) and GS 8 (P = 0.0057) patients compared to samples of healthy men, respectively. However, PCa aggressiveness was not predictable by Eotaxin-1 levels. In line with serum analyses, urine Eotaxin-1 was significantly decreased in patients with PCa compared to cancer-free individuals (P = 0.0185) but was not different between cancers of different GS. Patientś follow-up analyses showed no significant correlation between serum Eotaxin-1 levels and time to biochemical recurrence. Survival analyses also revealed no significant changes in progression-free survival among low (≤ 112.2 pg/ml) and high (> 112.2 pg/ml) Eotaxin-1 serum levels., Conclusion: Although this study has not established a prognostic role of Eotaxin-1 in PCa patients, this chemokine may serve as a diagnostic marker to distinguish between disease-free prostate and cancer., (© 2015 Wiley Periodicals, Inc.)

Background: Epithelial-to-mesenchymal transition (EMT) has been reported involved in the pathogenesis of fibrotic disorders and associated with stemness characteristics. Recent studies demonstrated that human benign prostatic hyperplasia (BPH) development involves accumulation of mesenchymal-like cells derived from the prostatic epithelium. However, the inductive factors of EMT in the adult prostate and the cause-and-effect relationship between EMT and stemness characteristics are not yet resolved., Methods: EMT expression patterns were immunohistochemically identified in the human epithelia of normal/BPH prostate tissue and in a rat BPH model induced by estrogen/androgen (E2/T, ratio 1:100) alone or in the presence of the ER antagonist raloxifene. Gene expression profiles were analyzed in micro-dissected prostatic epithelia of rat stimulated by E2/T for 3 days., Results: Two main morphological features both accompanied with EMT were observed in the epithelia of human BPH. Luminal cells undergoing EMT dedifferentiated from a cytokeratin (CK) CK18(+) /CK8(+) /CK19(+) to a CK18(-) /CK8(+) /CK19(-) phenotype and CK14 expression increased in basal epithelial cells. ERα expression was closely related to these dedifferentiated cells and the expression of EMT markers. A similar pattern of EMT events was observed in the E2/T induced rat model of BPH in comparison to the prostates of untreated rats, which could be prevented by raloxifene., Conclusions: Epithelial and mesenchymal phenotype switching is an important mechanism in the etiology of BPH. ERα mediated enhanced estrogenic effect is a crucial inductive factor of epithelial dedifferentiation giving rise to activation of an EMT program in prostate epithelium., (© 2014 Wiley Periodicals, Inc.)

Background: Advanced prostate cancer is treated by hormone ablation therapy. However, despite an initial response, the majority of men relapse to develop castration-resistant disease for which there are no effective treatments. We have previously shown that manipulating individual proteins has only minor alterations on the resistant phenotype so we hypothesize that targeting the central transcription factors (TFs) would represent a better therapeutic approach., Methods: We have undertaken a transcriptomic analysis of gene expression differences between the androgen-dependent LNCaP parental cells and its castration-resistant Abl and Hof sublines, revealing 1,660 genes associated with castration-resistance. Using effective bioinformatic techniques, these transcriptomic data were integrated with TF binding sites resulting in a list of TFs associated with the differential gene expression observed., Results: Following validation of the gene-chip results, the serum response factor (SRF) was chosen for clinical validation and functional analysis due to its recent association with prostate cancer progression. SRF immunoreactivity in prostate tumor samples was shown for the first time to be associated with castration-resistance. SRF inhibition by siRNA and the small molecule inhibitor CCG-1423 resulted in decreased proliferation., Conclusion: SRF is a key TF by which resistant cells survive with depleted levels of androgens representing a target for therapeutic manipulation., (Copyright © 2013 Wiley Periodicals, Inc.)

Background: The currently used prostate cancer serum marker has a low cancer specificity and improved diagnostics are needed. Here we evaluated whether autoantibodies are present in sera of prostate cancer patients and whether they are useful diagnostic markers for prostate cancer., Methods: Sera from 20 prostate cancer patients and 20 healthy controls were incubated on expression clone arrays containing more than 37,000 recombinant human proteins. Functional annotation clustering of the identified autoantigens was performed using the DAVID database. Autoantigens identified in the prostate cancer group were validated on microarrays using sera of 40 prostate cancer patients, 40 patients with elevated PSA levels but prostate cancer negative biopsies (benign disease), and 40 healthy controls., Results: We detected autoantibodies against 408 different antigens in sera of prostate cancer patients. One hundred seventy-four of these were exclusively detected in the cancer group compared to the healthy control group. Functional annotation clustering revealed an enrichment of RNA-associated, cytoskeleton, and nuclear proteins. The autoantibody panel was validated in serum samples of independent prostate cancer patients. Autoantibody profiles discriminated between prostate cancer patients and benign disease patients with an ROC curve AUC of 0.71. TTLL12, a protein recently described to be over-expressed in prostate cancer, was the highest ranked discrimination autoantigen., Conclusion: A variety of autoantibodies were identified in sera of prostate cancer patients and provide a first step towards autoantibody diagnostics. Serum autoantibodies reflect the disease and represent valuable tools not only for prostate cancer, but also for other diseases affecting the immune response., (Copyright © 2011 Wiley Periodicals, Inc.)

Background: AGR2 is a member of the endoplasmatic reticulum protein disulphide isomerase gene family implicated in tumor metastasis. Its expression pattern, function, and utility as a marker remains to be further investigated., Methods: Using real-time RT-PCR and immunohistochemistry, changes of expression in different tumor stages were explored in microdissected tumor samples. AGR2 transcript level in urine sediments was scrutinized for suitability as a tumor marker. AGR2 androgen regulation and function were analyzed in cellular prostate cancer models., Results: AGR2 is highly expressed in prostate cancer compared to benign tissue in particular also in low-grade tumors and PIN lesions. AGR2 transcripts were detected in urine sediments of patients undergoing prostate biopsy with significantly higher levels in tumor patients. The urine AGR2/PSA transcript ratio allowed much better discrimination between cancer and benign patients than serum total PSA or %freePSA. Prostate tumor cells express and secrete variable amounts of AGR2 protein, the highest level was found in PC3 cells. In androgen receptor-positive cell lines AGR2 is upregulated by androgens. Increased expression enhanced the migratory and invasive potential but decreased growth and proliferation in vitro and in vivo., Conclusion: AGR2 enhances the invasion phenotype of prostate cancer cells while at the same time attenuating cell-cycle progression. This function, its expression pattern and the increased level of AGR transcripts in urine sediments of prostate cancer patients call for further exploration as a prostate cancer marker and a modulator of tumor growth and invasion., (Copyright © 2010 Wiley-Liss, Inc.)

Background: Insulin-like growth factor binding protein 3 (IGFBP-3) exerts inhibitory and proapoptotic effects on prostate cancer cells. Serum levels of IGFBP-3 were found to be associated with the risk of prostate cancer, but the data are still inconclusive. We present a detailed analysis of the expression and localization of IGFBP-3 in the prostate and a comparison with its expression pattern in tumors., Methods: Expression and localization of IGFBP-3 were analyzed in cellular models and tissue by real-time RT-PCR, ELISA, immunohistochemistry, and immunofluorescence., Results: All cell types of a panel of benign epithelial, stromal and tumor prostate cells expressed IGFBP-3. Significantly higher expression levels were registered in stromal cells. TGF-beta stimulation boosted IGFBP-3 levels 60-fold in stromal cells. The pattern of expression was confirmed in microdissected tissue samples. Protein levels measured by ELISA paralleled the mRNA levels and more than 80% of IGFBP-3 was secreted. On tissue immunostaining, IGFBP-3 was found to be mainly located in the epithelium. The pattern suggested secretion of IGFBP-3, which was confirmed in prostate tissue cultured ex vivo and the ejaculate of vasectomized men. IGFBP-3 levels were increased in primary tumors but did not differ from benign epithelium in metastases and local recurrent tumors., Conclusions: We registered a significant local production of IGFBP-3 in the prostate, which may well override the effect of protein entering from blood. The stroma--particularly reactivated stroma--is the main source of IGFBP-3 in the prostate, suggesting that this peptide acts as a mediator of stromal-epithelial interactions., (Copyright (c) 2008 Wiley-Liss, Inc.)

Background: RhoE/Rnd3, a recently described novel member of the Rho GTPases family, was discussed as a possible antagonist of the RhoA protein that stimulates cell cycle progression and is overexpressed and/or overactivated in prostate cancer. We investigated the expression of RhoE and its role in cell cycle regulation and apoptosis in the human prostate., Methods: RhoE expression in cell lines and tissue specimens was assessed by immunoblot analysis, real-time PCR (RT-PCR), and immunohistochemistry. To elucidate RhoE effects on the prostate, RhoE was cloned and overexpressed in DU-145 prostate cancer. Cell cycle modulation and apoptosis was investigated by immunoblot and FACS analysis., Results: Immunoblot analysis showed a strong RhoE signal in both, benign epithelial and stromal cells. In contrast, almost no protein was detected in various prostate cancer cells. On RT-PCR and microarray analysis, RhoE mRNA expression was significantly reduced in malignant tissue when compared to benign samples. RhoE immunostaining was strong in benign tissue, especially in prostate epithelial cells, whereas it was minimal or absent in malignant tissue. Forced RhoE overexpression in a prostate cancer cell line inhibits the expression of two proteins essential for G2/M transition, namely CDC2 and cyclin B1, and induces G2/M arrest. In addition, apoptotic cell death as measured by a cleavage product of caspase 3 is significantly increased in RhoE-overexpressing cells., Conclusion: In conclusion, our findings suggest RhoE as a tumor suppressor gene that is downregulated early in the development of prostate cancer., (Copyright 2005 Wiley-Liss, Inc.)

Background: To determine longitudinal PSA changes over a period of 10 years in patients with and without prostate cancer., Methods: Serial PSA measurements performed over 10 years were evaluated in 353 men who eventually developed prostate cancer and in 2.462 participants of a screening program without prostatic malignancy., Results: In men with cancer, mean tPSA increased from 2.28 ng/ml at 10 years before diagnosis to 6.37 ng/ml at the time of postive biopsy (PSA velocity: 0.409 ng/ml/year). PSA velocity was significantly associated with Gleason scores and pathologic stage. In the benign group (n=2.462), mean tPSA increased from 1.18 to 1.49 ng/ml over a period of 10 years (PSA velocity of 0.03 ng/ml/year). Of the subjects with tPSA levels of 2 ng/ml or less, 2 years prior to cancer diagnosis, 11.4% had tPSA values of more than 4 ng/ml at the time of biopsy. Of the 972 men with tPSA below 1 ng/ml 2 years before the most recent measurement was obtained, 966 (99.4%) had no evidence of prostate cancer 2 years later, while six were found to have malignancies (0.6%)., Conclusions: Longitudinal PSA changes in men with and without prostate cancer are significantly different. Annual testing may not be required in men with baseline tPSA levels of 1 ng/ml or below, whereas in patients with levels higher than 1 ng/ml, it seems to be indicated because of the significant percentage of men presenting with tPSA levels of more than 4 ng/ml two years later., ((c) 2005 Wiley-Liss, Inc.)

Background: Prostate-specific antigen (PSA) is a widely used serum marker for prostate cancer, but has a poor specificity for early detection at levels below 10 ng/ml, because it can also result from benign conditions. Our aim was to determine the frequencies of circulating PSA+ macrophages in a blinded study and to examine the suitability of this new method for differentiating between benign and malignant prostate disease., Methods: Between October 2002 and February 2003, 126 patients undergoing transrectal biopsy were enrolled in this study. Peripheral blood macrophages were stained for intracellular content of PSA in all patients. Ten patients' peripheral blood mononulear cells (PBMCs) were also supplementarily stained for cytokeratin (CK) and epithelial membrane antigen (EMA). Macrophages were analysed by flow cytometry. Patients were grouped according to their biopsy histology and bone scan results., Findings: Based on histological data, patients were classified as having no evidence of malignancy (NEM) (n = 59), prostatitis (n = 20), or localised prostate cancer (n = 37). Significantly higher levels of circulating PSA+ macrophages were found in prostate cancer compared to benign conditions. Calculating a 2% cut-off level enabled the detection of localised prostate cancer with 89% sensitivity and 80% specificity. In a subset of patients (65%) with a serum PSA below 4 ng/ml and confirmed prostate cancer, the percentage of PSA+ macrophages was significantly higher compared to NEM and prostatitis. Macrophages of ten patients tested with prostate cancer contained significantly higher amounts of PSA, EMA, and CK compared to ten with NEM., Interpretation: Intracellular PSA in combination with CK and EMA can be found in permeabilized blood macrophages, indicating phagocytosis of complete cancer cells. This study further suggests, that this new method might be suitable for differentiating between prostate cancer and benign conditions especially in patients with low serum PSA., (2004 Wiley-Liss, Inc.)

Background: In spite of increasing knowledge about the tumor biology of prostate cancer (PC), molecular events involved in tumor progression are not well characterized. There is evidence that a number of genetic alterations play a role in tumor progression and in addition, angiogenesis also contributes. In this study, comparative genomic hybridization (CGH), a sensitive method for detecting regional DNA copy number abnormalities, and microsatellite analysis was used to identify frequent genome changes in PC. Correlation of these data with microvessel density (MVD) and clinical follow-up data was performed to determine genetic alterations that are associated with angiogenesis and subsequent tumor progression., Methods: Fifty-seven paraffin embedded radical prostatectomy (RP) specimens were microdissected. DNA from the microdissected PC tissue was amplified by degenerate oligonucleoitide primed (DOP)-polymerase chain reaction (PCR), and CGH was performed on the PCR product. Quantitative analyses of the CGH profiles were performed using a t-statistic. Additionally, a microsatellite analysis of chromosome 13q was performed on a subgroup of 31 of the tumors. Using a polyclonal antibody against factor VIII, MVD was determined for all RP specimens. The results of CGH and microsatellite analysis were correlated with the clinical data of the patients and with MVD., Results: Forty-two of the tumors (75%) showed one or more gains while 39 (70%) showed one or more losses per tumor. The most frequent DNA copy number gains were on chromosome 3, 4, 7, 8, 10, 11, 12, 13, and X. The most frequent losses were on chromosomes 2, 5, 6, 8, 10, 13, 15, and 16. Cancer recurrence occurred in 15 patients. The total number of DNA copy number losses was significantly higher in patients with this progression (86%) than without (52%) (P < 0.001). There was no significant difference in the number of gains in patients with or without progression. Contingency table analysis showed a significant correlation between progression and losses in regions of chromosomes 6q and 13q and a gain of chromosome 7q. In multivariate analysis, only loss of chromosome 6 was independently prognostic. The gains that correlated most closely with MVD > 35 were on chromosomes 2q, 7q, and Xq, while the losses most closely associated with MVD > 35 were on chromosomes 8q, 10q, and 13q. However, only the association between loss of chromosome 13q and MVD > 35 was statistically significant. Microsatellite analysis revealed a statistically significant correlation between MVD and instability of locus 171., Conclusions: This study indicates that the frequency of genetic alterations in PC as detected by CGH correlates with clinical outcome, and that losses of DNA from chromosomes 6q and 13q are important events that correlate with tumor progression, with loss of 13q, especially instability of locus 171, also associated with angiogenesis., (Copyright 2004 Wiley-Liss, Inc.)

Background: When age-referenced PSA levels as recommended by Oesterling et al.1 were used as a biopsy criterion, only 25% of the cancers detected in a population based PSA Screening Project were organ-confined. This observation led to the decision to use low PSA levels as the sole indication for biopsy. Since 1995 age-referenced PSA levels of 1.25-3.25 ng/ml have been used in combination with a percentage free PSA cutoff of 18%. This PSA cutoff reduction led to a statistically significant migration to lower pathological stages with a decreased prostate cancer mortality in the years 1996-2001. However, concerns have been raised that screening with low PSA levels may detect clinically insignificant cancers., Materials and Methods: We evaluated prostate cancer patients with low PSA levels in terms of heterogeneity, clinical significance, multifocality, and tumor biology including ploidy and proliferation index., Results: Concerning heterogeneity the Gleason score of the needle biopsy failed to predict the Gleason score of the radical prostatectomy specimen in nearly 40% of prostate cancer patients; regarding multifocality 65% of patients with low PSA levels showed multifocal lesions and 36% exhibited tetraploid DNA distribution; more than 50% of tetraploid tumors were found in patients with tumor volumes of less than 0.5 cm(3). Ploidy correlated with the Ki-67 proliferation index, but not with tumor volume., Conclusions: These results demonstrate that small prostate cancers with low PSA levels and low tumor volumes exhibit all features of prostate cancers with higher tumor volumes and show the characteristics of malignant cancers, i.e., multifocality, tetraploidy, and high proliferative activity., (Copyright 2003 Wiley-Liss, Inc.)

Background: In advanced stages of prostate cancer, the phosphatidylinositol-3' kinase (PI3K)/Akt signaling cascade, one of the major survival pathways in the cell, is frequently constitutively activated due to mutation or loss of the tumor suppressor protein phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Using cell culture models representing different tumor stages, we explored the effect of inhibition of this survival pathway on the induction of apoptosis., Methods: Inhibition of the survival kinase Akt and induction of apoptosis was analyzed in androgen-insensitive DU145 and PC-3 cells, in androgen-responsive LNCaP, and in androgen-independent long-term androgen-ablated LNCaP-abl cells representing therapy-resistant prostate cancer cells. Activated Akt was determined by immunoblotting using a phospho-Akt specific antibody. Induction of apoptosis was analyzed employing annexing V and propidium iodide staining and flow cytometry and measurement of cleavage of the caspases substrate poly-ADP-ribose polymerase (PARP)., Results: IGF-1, EGF, and heregulin but not PDGF or activators of protein kinase A induced phosphorylation of Akt in DU145 cells and activation was completely blocked by the PI3K inhibitor LY294002. In the hormone-responsive prostate cancer cell line LNCaP that has a constitutively switched-on Akt kinase, LY294002 caused a dose- and time-dependent Akt inhibition, which was absent in long-term androgen-ablated LNCaP sublines. In agreement with the resistance to inhibition of the PI3K/Akt pathway, long-term androgen-ablated LNCaP sublines remained relatively resistant to induction of cell death by LY294002 or the cytotoxic drug etoposide. Inhibition of the PI3K/Akt pathway restored the sensitivity of long-term androgen-ablated cells to induction of apoptosis by a cytotoxic drug almost completely., Conclusion: These results suggest that long-term androgen ablation therapy for prostate cancer reinforces the PI3K/Akt pathway and impedes its inhibition thus contributing to increased resistance of tumor cells to induction of apoptosis. With regard to treatment of therapy-refractory prostate cancer, these findings suggest effectiveness of a combination of cytotoxic treatment and inhibition of the PI3K-Akt survival pathway in tumor cells after failure of androgen-ablation therapy., (Copyright 2003 Wiley-Liss, Inc.)

Background: The present study was designed to investigate whether the clinical or pathologic features of prostate cancer (PCa) are related to the number of repeat biopsies required to establish the diagnosis of PCa., Methods: Between February 1993 and August 2000, 653 patients were evaluated in this retrospective study. All patients underwent transrectal ultrasound-guided biopsy of the prostate prior to radical retropubic prostatectomy. The pathologic findings of specimens obtained at radical prostatectomy and pelvic lymph node dissection as well as PSA levels, findings on DRE, prostate volumes, transition zone volumes, and age were analyzed separately for all PCa patients diagnosed at the first set of biopsies (group A) and compared with the data of those diagnosed at the 2nd-5th set of biopsies (group B). In a second step, we compared the results obtained from patients diagnosed at the 2nd set of biopsies (group B1) with those of patients diagnosed at the 3rd to 5th set of biopsies (group B2)., Results: Gleason scores, pathologic tumor stages, and tumor volumes in group B were found to be significantly decreased compared to group A. But from the 2nd to 5th serial biopsy no further decrease in pathologic stage, Gleason score, or tumor volume was observed. On the contrary, there was a tendency towards higher tumor stages and Gleason scores. Of the tumors detected after the second false-negative set of biopsies almost 70% were lesions with Gleason scores of 6 or higher., Conclusions: False-negative results at the first needle biopsy are predictive of a lower pathologic stage and grade as well as smaller tumor volumes of PCa diagnosed at repeat sets of biopsies. False-negative results on repeat biopsy, however, have no prognostic significance for the tumor stage of PCas detected at subsequent sets of biopsies., (Copyright 2003 Wiley-Liss, Inc.)

Background: Local hypoxia may be one of the triggers of embryonic reawakening of the stroma and subsequent hyperplastic growth in the prostate. Using a cell culture model of human prostatic stromal cells, we investigated the effects of hypoxia on activation of hypoxia-inducible factor 1 (HIF 1) and on the production of growth factors., Methods: Primary prostatic stromal cells were grown in normal and hypoxic (1% O(2)) atmosphere. Activation of HIF 1 was evaluated after different time intervals by Western blot. Induced secretion of growth factors VEGF, FGF-7, TGF-beta, IL 8, and FGF-2 were analyzed by ELISA. To confirm the in vitro findings we also performed immunohistochemistry of HIF 1alpha as well as pro-collagen I, collagens I, III, and IV in the benign tissue of radical prostatectomy specimens., Results: HIF 1 is activated in a time-dependent manner, already starting 1 hr after exposure of stromal cells to hypoxic conditions. Secretion of VEGF, FGF-7, TGF-beta, FGF-2, and IL 8 is increased under hypoxic in vitro conditions in comparison to normoxia. Levels of TGF-beta, VEGF, and IL 8 were rapidly and statistically significantly increased in the supernatant of hypoxic cells. Consistent with the in vitro findings, immunohistochemistry of HIF 1alpha in (benign prostatic hyperplasia) BPH tissue revealed strong HIF 1alpha nuclear staining in hyperplastic areas. No difference was observed in the collagen pattern between hyperplastic and normal prostate tissue., Conclusions: Prostatic stromal cells respond to hypoxia by upregulation of secretion of several growth factors suggesting that hypoxia can trigger prostatic growth. Therefore, hypoxia might be a key factor contributing to the pathogenesis of BPH., (Copyright 2003 Wiley-Liss, Inc.)

Background: In the literature, positive margins in radical prostatectomy specimens, the rate of which ranges between 7% and 46%, are associated with adverse patient survival. The aim of the present study was to determine the predictive value of preoperative serum prostate specific antigen (PSA) values for the rate of positive margins in radical retropubic prostatectomy., Methods: The study included a cohort of 845 patients who underwent radical retropubic prostatectomy between October of 1993 and December of 1999. All patients were stratified in groups on the basis of their preoperative PSA values: PSA group I, 0-1.99 ng/ml; PSA group II, 2-3.99 ng/ml; PSA group III, 4-5.99 ng/ml; PSA group IV, 6-7.99 ng/ml; PSA group V, 8-9.99 ng/ml; and PSA group VI, >10 ng/ml. For each group, the pathologic stage, Gleason score, and the incidence of positive margins were analyzed. For statistical analysis, the Mann Whitney U-test was used., Results: Our data show a significantly higher rate of organ-confined prostate cancers and a significantly lower rate of positive surgical margins in patients with preoperative total PSA values of less than 4 ng/ml compared with patients with higher preoperative total PSA levels., Conclusion: As tumor stage and surgical margin status after radical prostatectomy are important predictors of the likelihood of PSA recurrence, which necessitates additional therapy, these findings support the concept of PSA screening by using low PSA cutoff levels., (Copyright 2002 Wiley-Liss, Inc.)

Background: The androgen receptor (AR) promotes growth and functionality of androgen sensitive benign and cancer tissues. The pineal hormone melatonin is an androgen protagonist in vivo and in vitro. The interference of melatonin in the AR cascade was explored., Methods: The effects of melatonin on AR expression, level, agonist and androgen-response element (ARE) binding, reporter gene activity and intracellular localization were explored in prostate cancer LNCaP cell line., Results: Melatonin increased immunoreactive AR cells in the absence and presence of dihydrotestosterone. Despite this increase and maintenance of AR agonist binding capacity, the androgen-induced reporter gene activity and suppression of AR-mRNA were attenuated. Immunocytochemical analysis and subcellular fractionation studies revealed nuclear exclusion of AR by melatonin., Conclusions: The melatonin-mediated nuclear exclusion of the AR may explain the attenuation of AR activity in the prostate cancer cells. This is the first demonstration of a hormone-induced mislocalization of the AR in prostate epithelial cells and may represent a novel route for regulating AR activity., (Copyright 2001 Wiley-Liss, Inc.)

Background: Physiology of the human rhabdosphincter and its innervation are still a subject to controversy. A better understanding of rhabdosphincter function and anatomy might help to solve important urological problems like urinary incontinence. It was the aim of the present study to develop a human sphincter cell culture model for investigation of contraction mechanisms in vitro. METHODS AND RESULTS Cells were isolated from human rhabdosphincter tissue obtained from prostatectomy and cystoprostatectomy specimens. Cultured cells expressed typical features of striated muscle cells. By means of videomicroscopy with a time lapse videosystem cell contractions could be documented. Under control conditions without any contractile stimulant 8% of the cells were seen to contract. Cholinergic stimulation with 10 mM of acetylcholine induced a significant increase in contraction rate to 49%., Conclusions: These results demonstrate that cholinergic stimulation triggers contraction of cultured human rhabdosphincter cells. This model might help to understand external urethral sphincter physiology and to establish new therapies for the treatment of sphincter dysfunctions. Prostate 47:189-193, 2001., (Copyright 2001 Wiley-Liss, Inc.)

Background: Androgen receptor (AR) transcriptional activity is modulated by cofactor proteins. They act as costimulators, corepressors, or bridging proteins, and a disbalanced expression may contribute to the altered activity of the AR in advanced prostate cancer. We investigated the expression of a series of steroid receptor cofactors in prostate cancer cell lines, including several LNCaP sublines, and in prostate stromal cells., Methods: Expression of cofactors was analyzed by means of RT-PCR in PC-3, Du-145, LNCaP, three sublines of LNCaP established after long-term androgen deprivation, and two strains of primary prostate stroma cells. Expression in LNCaP and LNCaP-abl cells (which represented an advanced tumor cell) was analyzed employing semiquantitative RT-PCR., Results: Ten of the 12 cofactors tested were expressed in all cells analyzed (AIB1, ARA54, ARA70, CBP, cyclin D1, Her2/neu/erbB2, BAG-1/M/L, SRC-1, SMRT, and TIF2). Only ARA55 and FHL2 mRNAs were not detected in all cells. ARA55 mRNA was absent in LNCaP cells, LNCaP sublines, and DU-145 cells; FHL2 was not expressed in LNCaP cells and its derivatives. The expression pattern was identical in LNCaP cells, and the long-term androgen ablated LNCaP sublines. Moreover, comparison of expression levels in LNCaP and LNCaP-abl cells revealed a slight reduction in LNCaP-abl cells but no gross differences., Conclusions: Prostatic cells express a great number of steroid receptor cofactors. AR activity thus seems to be modulated in a very complex way in prostate cells., (Copyright 2000 Wiley-Liss, Inc.)

Background: Prostatic stromal cells are believed to be a key factor in the pathogenesis of benign prostatic hyperplasia (BPH). The effect of phenylephrine, an alpha1-adrenergic receptor agonist, and doxazosin, an alpha1-adrenergic receptor-specific antagonist, on the expression of smooth muscle myosin-heavy-chain isotypes SM-1 and SM-2 was tested in an in vitro model of prostatic smooth muscle cells (SMC)., Methods: Primary prostatic stromal cells, grown in SMC-specific medium, were treated with 10 microM of phenylephrine or 1 microM of doxazosin or a combination of both. SM-2 to SM-1 mRNA ratios and expression of alpha1-adrenergic receptor subtypes were determined by means of reverse transcriptase polymerase chain reaction (RT-PCR) techniques. Cell growth was measured by a cell viability assay., Results: SM-1 mRNA and only very low levels of SM-2 mRNA were detected in prostatic SMC cultures grown for 4 days in a serum-free base medium. After 6 days of treatment, SM-2 expression increased, highest in the doxazosin-treated cultures. In comparison to unstimulated cells, a statistically significant 10-fold increase of the SM-2:SM-1 ratio was measured in doxazosin-treated cultures. Analysis of alpha1-adrenergic receptor subtype expression revealed the presence of mRNAs of subtypes 1d and 1b mRNAs. Subtype 1a was not expressed. Phenylephrine and doxazosin showed no significant effect on cell proliferation and on alpha1d-adrenergic receptor expression., Conclusions: SMC can differentiate from a proliferative to a contractile phenotype, which is accompanied by increased expression of isotope 2 of smooth muscle myosin heavy chain. Our results suggest that doxazosin seems to have a long-term effect on the differentiation of prostatic stromal cells, indicating that alpha1-adrenergic receptor antagonists do not act solely on SMC contractility.

Background: Stromal-cell contractility is known to play an important role in the development of bladder outlet obstruction secondary to benign prostatic hyperplasia (BPH). An in vitro model of single-cell contraction was developed to investigate the effect of alpha1-adrenoceptor agonists and antagonists., Methods: Human prostatic stromal cells were isolated from prostatectomy and cystoprostatectomy specimens. The cells were cultured in a selective medium supplemented with growth factors and steroid hormones. The culture flasks were coated with a viscous agent to allow cell contraction. Contractions were visualized by means of a cell-culture microscope fitted with a time-lapse video system. For quantitative analysis, the percentage of contracting cells was evaluated., Results: Nineteen percent of the cells were found to contract without stimulation. Following incubation with doxazosin (10 nM, 100 nM, and 1 mM), there was a slight dose-dependent decrease in the number of spontaneously contracting cells, whereas adrenergic stimulation using 10 microM of phenylephrine led to a significant increase in the percentage of contracting cells (55%). Following incubation with 100 nM of doxazosin, the phenylephrine-induced effect was significantly reduced., Conclusions: This simple in vitro model of cell contraction in the prostate provides a useful means of investigating drug effects on prostatic stromal cells.

Background: Monoclonal antibodies B1 and B3 react with Lewis(y) and related carbohydrate antigens, which are abundant in many solid tumors. These antibodies, when conjugated to a toxin, have been used to target a variety of cancers. Treatment options for advanced prostate cancer are very limited, and there is a need to develop new therapies. In this study, we have asked whether antibodies B1 and B3 react with metastatic lesions from human prostatic carcinoma., Methods: Indirect streptavidin-biotin peroxidase immunohistochemistry was performed on formalin-fixed specimens from prostate cancer metastases. A total of 6 lymph node metastatic samples from patients who did not receive endocrine treatment and specimens of 14 distant metastases from patients who failed hormonal therapy were obtained., Results: Of the samples, 6 lymph node and 11 distant metastases stained for B1. In the case of B3 staining, 6 lymph node and 10 distant metastatic lesions were positive. In about half of these metastatic samples, more than 40% of cells were immunoreactive with either antibody. Two metastatic samples stained neither for B1 nor for B3 antibody. In general, B1 staining intensity was stronger in samples in which more than 40% of cells were positive., Conclusions: Our results suggest that B1 and B3 immunoconjugates could be applied to target a substantial percentage of prostate cancer metastases.

Background: Endocrine therapy for prostate cancer aims to reduce the levels of circulating androgen or to inhibit androgen action by blocking the androgen receptor in the prostate, or both. Studies in various animal and human prostate cancer models suggested that there may be a downregulation of androgen receptor during prostate cancer progression. Recent work, however, showed androgen receptor expression in all stages of prostate cancer. The presence of mutant androgen receptors in a portion of prostate cancers and receptor activation in the absence of androgen or in the presence of low androgen concentrations is discussed within this context., Methods: This review attempts to summarize the literature on androgen receptor expression in vitro and in vivo, as well as structural and functional alterations and communication between androgen signal transduction cascade and other signaling pathways., Conclusions: Prostate tumors adapt to an environment with low androgen supply by using a hyperactive androgen receptor. The mechanisms involved are mutations of the androgen receptor generating receptors with broadened activation spectrum, increased receptor expression, and activation by interaction with other signaling pathways.

Background: We investigated modulation of androgen receptor (AR) activity in prostatic tumor cells by luteinizing hormone-releasing hormone (LHRH)-induced increase of the intracellular cyclic adenosine monophosphate (cAMP) level., Methods: AR transactivation activity was assessed in transiently transfected DU-145 and in LNCaP cells., Results: LHRH and cAMP derivative, respectively, induced reporter gene activity to about 15% of the maximal level in DU-145 cells transfected with an AR expression vector and an androgen-inducible reporter gene. LHRH or the cAMP analogue acted synergistically in combination with low concentrations of androgen thus lowering the androgen concentration required for maximal AR activation by a factor of 100. A similar activation of the AR by cAMP analogue was observed in LNCaP cells when enhancement of androgen-induced secretion of prostate-specific antigen was determined. The two nonsteroidal antiandrogens hydroxyflutamide and Casodex(R) inhibited reporter gene activity., Conclusions: The AR is synergistically activated by low doses of androgen and LHRH or the second messenger cAMP. This may have implications for the treatment of advanced prostate cancer.

Background: Both benign and malignant growth of the prostate depend on the induction of a microvasculature. Basic fibroblast growth factor (bFGF), a potent angiogenic factor, is thought to play an important role in this process., Methods: bFGF expression in prostatic carcinoma was assessed by ELISA, reverse transcription polymerase chain reaction, and immunohistochemistry., Results: DU-145 and PC-3 tumor cells produced bFGF. Almost 80-90% of it was localized in the cytoplasm, and 10-20% was associated with extracellular matrix components. Immunohistochemical analysis of prostatic tissue sections showed that cancer cells stained more intensively as compared to putatively healthy epithelium. In prostate cancer patients, mean bFGF serum levels were significantly elevated when compared to a healthy control group (6.64 pg/ml vs. 1.28 pg/ml). Serum bFGF levels did not correlate with any other clinical marker such as PSA, tumor stage, or grade. Four out of five patients who progressed to a more advanced stage showed an increase in serum bFGF levels., Conclusions: These results suggest that increased bFGF release may be associated with a more aggressive tumor phenotype.

Approximately 20% of prostate cancers originate in the transition zone (TZ). Although transrectal ultrasound (TRUS) and systematic biopsies have improved peripheral zone (PZ) cancer diagnosis, additional biopsies directed into the TZ may further improve cancer detection. To evaluate the frequency and clinical significance of TZ cancers, we added two TZ biopsies to the routinely performed sextant biopsies. Three hundred forty patients (aged 45-75) from our prostate-specific antigen (PSA) screening study (21,078 volunteers) with negative rectal examination findings underwent systematic and TZ biopsies with three-dimensional ultrasound equipment. All patients had elevated PSA levels according to age-specific reference ranges. Ninety-eight of 340 men (28.5%) had biopsies positive for cancer. Of these 98 cancers, 28 (28%) originated in the TZ only and 5 (5%) were located in the TZ as well as the PZ. Eight men showed TZ abnormalities on ultrasound images, of whom four had biopsies positive for TZ cancer. The TZ cancers detected were pathologically significant in 96% (27 of 28). Seventy-one percent (20 of 28) of pathologically staged cancers were found to be organ confined and all combined TZ and PZ cancers were advanced tumors. We conclude that TZ biopsies enhance the cancer detection rate in prostate cancer screening and should therefore be added to the routinely done sextant biopsies in men with PSA elevation and normal digital rectal examination findings.

Smooth muscle cells (SMCs) constitute a major cellular component of prostatic stroma. SMC tension plays an important role in urethral obstruction secondary to benign prostatic hyperplasia (BPH). We have developed an in vitro procedure for the propagation of human prostatic SMCs. Tissue specimens from patients undergoing radical prostatectomy or cystectomy were enzymatically disaggregated and cultured in MCDB-131 medium supplemented with horse serum, insulin, conditioned medium from the tumor cell line CRL-5813, and steroid hormones. The medium was assembled on the basis of the effects these supplements have on the growth of SMC cultures and on the expression of the two markers desmin and smooth muscle myosin. Addition of 0.1 microM of estradiol to the growth medium dramatically increased expression of these SMC-specific markers. Dihydrotestosterone (DHT) and hydrocortisone had a similar, albeit less pronounced effect. At three to five passages, about two thirds of the cells were immunohistologically positive for smooth muscle myosin or desmin. Almost all cells were positive for the myofibroblast marker smooth muscle alpha-actin throughout 10 passages and more. In SMC cultures, cells staining for smooth muscle myosin and desmin were found to seek direct contact to myofibroblasts. They grew in aggregates on a layer of myofibroblasts which adhered to the surface of the culture vessel. As revealed by transmission electron microscopy the cultured cells exhibited morphological features of myofibroblasts. Characteristics of smooth muscle cells, such as prominent bundles of microfilaments associated with dense bodies, basal laminae investing the cells, and numerous caveolae at the cell surfaces were regularly observed in cultures of low passages. After several passages, these features were markedly decreased and organelles of the biosynthetic system became more prominent. In summary, we present an in vitro model of prostatic SMCs and demonstrate that steroid hormones have characteristic effects on these cells. SMC cultures are expected to facilitate investigation of the functions and properties of human prostatic SMCs.

Polypeptide growth factors are positive and negative regulators of prostatic growth and function. Expression and biological effects of epidermal growth factor (EGF), transforming growth factors (TGFs) alpha and beta, fibroblast growth factors (FGFs), and insulin-like growth factors (IGFs) in the prostate have been extensively studied. EGF and TGF alpha, which share the same receptor, are strong mitogens for prostatic epithelial and stromal cells. Their paracrine mode of action in normal tissue and early-stage tumors is apparently altered towards an autocrine stimulation in hormone-independent tumors, which gain the ability to produce TGF alpha by themselves. TGF beta has a dual role in the regulation of prostatic growth. It inhibits growth of prostatic epithelial cells in culture and mediates programmed cell death after androgen withdrawal. However, advanced prostatic carcinomas become insensitive to the inhibitory effect of TGF beta. Several members of the FGF family have been identified in the prostate. They are mainly or exclusively expressed in the stromal cells, and stimulate the epithelial cells. In the rat Dunning tumor model, progression is accompanied by distinct changes in the expression of FGFs and their receptors. In the hyperplastic tissue, basic FGF (bFGF) is accumulated. This growth factor is also a potent angiogenic inducer, expression of which may determine the metastatic capability of a tumor. IGFs are paracrine growth stimulators in the normal and hyperplastic prostate. It is still under consideration whether prostatic cancer cells gain the ability to produce IGF-I by themselves and thus shift to an autocrine mode of IGF-I stimulation. Growth factors also interact with the androgen-signaling pathway. IGF-I in particular, other growth factors as well, can activate the androgen receptor.

Gemcitabine (2',2'difluoro-2'deoxycytidine, dFdC) is a synthetic antimetabolite of the cellular pyrimidine nucleotide metabolism. In a first series of in vitro experiments, the drug showed a strong effect on the proliferation and colony formation of the human androgen-sensitive tumor cell line LNCaP and the androgen-insensitive cell lines PC-3 and DU-145. Maximal inhibition occurred at a dFdC concentration as low as 30 nM. In contrast to the cell lines which were derived from metastatic lesions of prostate cancer patients, no inhibitory effects were found in normal primary prostatic epithelial cells at concentrations up to 100 nM. The effect of gemcitabine was reversed by co-administration of 10-100 microM of its natural analogue deoxycytidine. In view of a future clinical application of this anti-tumor drug in advanced prostatic carcinoma, we have compared the effect of gemcitabine on prostatic tumor cells with that on bone marrow granulopoietic-macrophage progenitor cells, because neutropenia is a common side effect of gemcitabine treatment. The time course of action on the two kinds of cells was markedly different. Colony formation of tumor cells was inhibited by two thirds at a gemcitabine concentration of about 3.5 nM. The same effect on granulopoietic-macrophagic progenitor cells required a concentration of 9 nM. Co-administration of deoxycytidine to gemcitabine-treated tumor cell cultures completely antagonized the effect of gemcitabine whereas addition of deoxycytidine after 48 hr of gemcitabine treatment could not prevent gemcitabine action on the tumor cells. In contrast, more than half of the granulopoietic-macrophagic progenitor cells could still be rescued by deoxycytidine administration after 48 hr. These findings and the marked difference in the susceptibility of neoplastic and normal prostatic cells suggest that gemcitabine is a promising substance which should be further evaluated as to its efficacy in the treatment of advanced prostatic carcinoma.

To date androgen receptor (AR) expression and structure in human prostatic cancer have been studied in primary tumor specimens and in cell lines. Investigation of alterations in the androgen-signalling transduction cascade in prostatic carcinoma metastases is important to improve our understanding of tumor progression towards androgen insensitivity. In the present study we have collected data comparing AR expression in both the primary tumors and the respective pelvic lymph node metastases. Formalin-fixed and paraffin-embedded tissues derived from the primary tumors and positive lymph nodes of 12 patients undergoing radical prostatectomy were immunostained for the AR and prostate-specific antigen (PSA). AR expression was evaluated with the polyclonal antibody PG-21, which is directed against amino acid 1-21 in the N-terminal region of the AR. All primary tumors stained for the AR. In 8 of the 12 lymph nodes examined more than 50% of the tumor cells were AR positive and displayed a uniform staining pattern; in one lymph node metastasis remarkable heterogeneity in AR expression was observed. In two cases less than 10% of the tumor cells stained for the AR. In one case the lymph node metastasis was immunohistochemically negative for the AR, whereas the primary tumor obtained from the same patient displayed intense staining for the AR. PSA was expressed in all metastases and primary tumors. Our data demonstrate that loss of the AR in lymph node metastases from prostatic carcinoma is a rare event.

Intracellular action of androgens is mediated by the androgen receptor (AR), which is a key element of the androgen signal transduction cascade and a target of endocrine therapy for prostatic carcinoma. Therefore, the qualitative and quantitative alterations of AR expression in prostatic carcinomas and their possible implications for tumor progression and treatment are of great interest. Findings in prostatic tumor cell lines of rat and human origin suggest a reduction of AR protein expression accompanied by an increase in tumor malignancy. However, immunohistochemical studies and binding assays demonstrated presence of ARs in all histological types of prostatic tumors, in therapy-responsive as well as in therapy-unresponsive ones. AR content of prostatic tumor specimens did not correlate with outcome of endocrine therapy of advanced prostatic carcinoma in these studies. Solely the degree of heterogeneity of AR expression may be useful as an indicator of responsiveness to therapy. AR mutations have been detected in the LNCaP cell line and in three primary prostatic tumor specimens. Three of them are point mutations in the hormone-binding domain of the AR, the fourth mutation is a CAG-microsatellite depression in the N-terminus. Evidence coming from studies on AR in prostatic cancer highlights the possibility that AR structural alterations may have significance in tumor progression.

Essentially all prostatic carcinomas relapse to an androgen-independent stage during androgen ablation therapy. The underlying genetic changes are still unclear. Such changes are suspected to affect the androgen-signalling pathway as well as growth promoting and inhibiting factors. This study was undertaken to test for structural changes of the androgen receptor in prostatic tumor cell lines and primary tumors. Complementary DNA (cDNA) fragments of the androgen receptor (AR) were isolated from the cell lines LNCaP, PC-3, and DU 145, ten tissue specimens obtained by radical prostatectomy, and five fine-needle biopsies by means of the polymerase chain reaction (PCR) technique. Fragments encoding the hormone- and DNA-binding domains were analyzed by DNA sequencing. The PCR technique is highly sensitive and especially recommended for the analysis of small tissue samples, such as those obtained by fine-needle aspiration. No alterations were detected in the tissue specimens and the five fine-needle aspirates. In the three tumor cell lines that represent late stages of prostatic tumor, different findings were obtained. The androgen-independent DU 145 cells did not express androgen receptors, whereas the PC-3 cells, which are also androgen-independent, expressed very low levels of normal AR. In contrast to this, the androgen-dependent LNCaP cells expressed high levels of structurally abnormal androgen receptors. These results suggest that androgen receptor mutations are probably uncommon molecular events in the early stages of prostatic cancer. Qualitative and quantitative changes, however, seem to occur in advanced prostatic cancer.