Search

Background:: One of the major challenges in prostate cancer (PCa) treatment is distinguishing insignificant PCa from those forms that need active treatment. We evaluated the impact of PSA isoforms on risk stratification in patients with low-risk PCa as well as in active surveillance (AS) candidates who underwent radical prostatectomy. Methods:: A total of 112 patients with biopsy confirmed Gleason score (GS) 6 PCa of four different international institutions were prospectively enrolled in the study. Blood withdrawal was performed the day before radical prostatectomy. In addition, patients were classified according to the EAU and NCCN criteria for AS candidates. PSA, free PSA (fPSA) and proPSA were measured using dual monoclonal antibody sandwich immunoassays. In addition, the Prostate Health Index (PHI=proPSA/fPSA × √PSA) was calculated. Final histology of the radical prostatectomy specimens was correlated to PSA, its isoforms and PHI. Results:: Serum proPSA levels were significantly elevated in those patients with an upgrade in final histology (GS⩾7). In addition, higher proPSA levels were predictive for extraprostatic extension (⩾pT3a) as well as for positive surgical margins. Interestingly, PHI had an even higher predictive power when compared with proPSA alone concerning GS upgrading, extraprostatic extension and surgical margins in both the total and the AS patient group. Conclusion:: We showed in a multicenter study that proPSA is a valuable biomarker to detect patients with aggressive PCa in a cohort of GS 6 patients, who would benefit from active tumor therapy. Combining proPSA with the standard markers PSA and fPSA using PHI further increases the predictive accuracy significantly. Moreover, our data support the use of PHI for monitoring PCa patients under AS.

Novel drugs like Abiraterone or Enzalutamide, which target androgen receptor (AR) signaling to improve androgen deprivation therapy (ADT), have been developed during the past years. However, the application of these drugs is limited because of occurrence of inherent or acquired therapy resistances during the treatment. Thus, identification of new molecular targets is urgently required to improve current therapeutic prostate cancer (PCa) treatment strategies. PIAS1 (protein inhibitor of activated STAT1 (signal transducer and activator of transcription-1)) is known to be an important cell cycle regulator and PIAS1-mediated SUMOylation is essential for DNA repair. In this context, elevated PIAS1 expression has already been associated with cancer initiation. Thus, in the present study, we addressed the question of whether PIAS1 targeting can be used as a basis for an improved PCa therapy in combination with anti-androgens. We show that PIAS1 significantly correlates with AR expression in PCa tissue and in cell lines and demonstrate that high PIAS1 levels predict shorter relapse-free survival. Our patient data are complemented by mechanistic and functional in vitro experiments that identify PIAS1 as an androgen-responsive gene and a crucial factor for AR signaling via prevention of AR degradation. Furthermore, PIAS1 knockdown is sufficient to decrease cell proliferation as well as cell viability. Strikingly, Abiraterone or Enzalutamide treatment in combination with PIAS1 depletion is even more effective than single-drug treatment in multiple PCa cell models, rendering PIAS1 as a promising target protein for a combined treatment approach to improve future PCa therapies.

Vibrational spectroscopic imaging has become an essential tool for tissue analyses in life science and represents a modern analytical technique enabling the detection and characterization of molecular components of biological samples. It is based on the absorption of IR radiation by vibrational transitions in covalent bonds and enables global analysis of samples, with resolution close to the cellular level. Advantage of vibrational spectroscopic imaging is the acquisition of local molecular expression profiles, while maintaining the topographic integrity of the tissue by avoiding time-consuming extraction, purification and/or separation steps, respectively. With this nondestructive analytical method it is possible to get both qualitative and quantitative information of heterogeneous samples and unique chemimorphological information about the tissue status, which represents an important benefit for future analytical interpretation of pathological changes of a tissue.

Two recent methods for obtaining flow stress-strain relations up to large strains of order 1.5 by channel-die compression are presented: i) for sheet metal formability tests, composite samples have been made of glued sheet layers and deformed at room temperature in a channel-die with the compression axis directed along one of the sheet metal edge directions, i.e. RD or TD. The sheet plane is parallel to the lateral compression die face. It is shown that, using a suitable lubricant, the sample deformation is homogeneous up to strains of 1.5. Tests carried out on 5xxx and 6xxx alloys to evaluate the stress-strain relations show that a generalized Voce law gives a good quantitative fit for the data. ii) for high temperature plate processing, quantitative flow stress data can be obtained up to 500°C with a rapid quench using a hot channel-die set-up. Some new results are presented here for high strain hot PSC tests on Al-Mn and Al-Mg alloys together with microstructure analyses.

Providing a rapid and sensitive protein profiling method for biomarker discovery from a variety of biological samples is crucial for the introduction of new markers that improve cancer patient diagnosis at early tumor stages, thus increasing the chances of curative treatment. We report here the development and application of derivatized cellulose particles for selective serum protein profiling. For immobilized metal ion affinity chromatography (IMAC), cellulose was derivatized with glycidyl methacrylate (GMA) and subsequently with iminodiacetic acid (IDA). To investigate the application of this material for generating protein profiles of human serum samples, the serum samples were agitated with the derivatized cellulose particles to a suspension and incubated for 2 h at 30 °C. After washing, 1 μL of the IDA-Cu²⁺-cellulose suspension was applied directly onto a MALDI-target, mixed with sinapinic acid (SA) and analyzed with MALDI-TOF MS. Consistent serum specific data were obtained from aliquoted samples analyzed several times, indicating the reliability of the method. However, the serum fingerprints obtained proved to be specific for any given serum. The technique presented allows a high enrichment of sample on the developed target leading to a high sensitivity and reproducibility without depletion of albumin and immunoglobulin, and sample elution prior to MS-analysis. The study demonstrates for the first time that derivatized cellulose particles combined with MALDI-TOF MS represent a simple, economical, and rapid approach to generate serum protein profiles for biomarker identification. Keywords: spherical cellulose • protein profiling • direct MALDI-TOF • prostate cancer

The androgen receptor (AR), a transcription factor that mediates the action of androgens in target tissues, is expressed in nearly all prostate cancers. Carcinoma of the prostate is the most frequently diagnosed neoplasm in men in industrialized countries. Palliative treatment for non-organ-confined prostate cancer aims to down-regulate the concentration of circulating androgen or to block the transcription activation function of the AR. AR function during endocrine therapy was studied in tumor cells LNCaP subjected to long-term steroid depletion; newly generated sublines could be stimulated by lower concentrations of androgen than parental cells and showed up-regulation of AR expression and activity as well as resistance to apoptosis. Androgenic hormones regulate the expression of key cell cycle regulators, cyclin-dependent kinase 2 and 4, and that of the cell cycle inhibitor p27. Inhibition of AR expression could be achieved by potential chemopreventive agents flufenamic acid, resveratrol, quercetin, polyunsaturated fatty acids and interleukin-1beta, and by the application of AR antisense oligonucleotides. In the clinical situation, AR gene amplification and point mutations were reported in patients with metastatic disease. These mutations generate receptors which could be activated by other steroid hormones and non-steroidal antiandrogens. In the absence of androgen, the AR could be activated by various growth-promoting (growth factors, epidermal growth factor receptor-related oncogene HER-2/neu) and pleiotropic (protein kinase A activators, interleukin-6) compounds as well as by inducers of differentiation (phenylbutyrate). AR function is modulated by a number of coactivators and corepressors. The three coactivators, TIF-2, SRC-1 and RAC3, are up-regulated in relapsed prostate cancer. New experimental therapies for prostate cancer are aimed to down-regulate AR expression and to overcome difficulties which occur because of the acquisition of agonistic properties of commonly used antiandrogens.

The classical homogenization methods cannot capture entirely the complexity of the microstructures encountered in material engineering and design. This paper presents three different types of approach, which all tend towards a refined description of the pertinent microstructural characteristics. The first one is a step‐wise homogenization based on a hierarchy of heterogeneity levels. It is applied to the prediction of elastic moduli of composites. The second one aims to better estimate the stress and strain distributions in and around inclusions with complex shapes. Semi‐analytical methods (for non‐ellipsoidal shapes) and numerical methods (for non‐convex ones) are developed. In the third case, the microstructure cannot be treated as an usual continuum. Discrete numerical methods are then derived for predicting the properties of fiber networks or cellular materials.

Objectives:Photodynamic diagnosis (PDD) is able to detect dysplasia and transitional cell cancer of the bladder. We report our first experiences using PDD in the urethra. Materials and Methods:Three patients with secondary transitional cell cancer of the urethra were treated by using PDD. 5–Aminolevulinic acid (ALA) was applied in a mixture with lubricant to achieve long enough contact with the urothelium. Negative effects were tested in vitro on three bladder cell lines. Results:In vitro assays showed no enhanced negative effects on the viability of bladder cells using the combination of ALA/lubricant and medium in comparison to lubricant/medium alone. All patients showed markedly fluorescent areas, which were resected. The treatment was well tolerated without side effects attributable to the photosensitizer containing lubricant. Conclusion:Lubricant with ALA forms a viscous solution, which can successfully be used for PDD in the urethra. Thus marking tumors by fluorescence may improve transurethral resection and thus preserve the urethra.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).

Objective:The development of the human benign prostatic hyperplasia clearly requires a combination of testicular androgens and aging. Although the role of androgens as the causative factor for human benign prostatic hyperplasia is debated, they undoubtedly have at least a permissive role. The principal prostatic androgen is dihydrotestosterone (DHT). Although not elevated in human benign prostatic hyperplasia, DHT levels in the prostate remain at a normal level with aging, despite a decrease in the plasma testosterone.Results:DHT is generated by reduction of testosterone. Two isoenzymes of 5α–reductase have been discovered. Type 1 is present in most tissues of the body where 5α–reductase is expressed and is the dominant form in sebaceous glands. Type2 5α–reductase is the dominant isoenzyme in genital tissues, including the prostate. Finasteride is a 5α–reductase inhibitor that has been used for the treatment of benign prostatic hyperplasia and male–pattern baldness. At doses used clinically, its major effect is through suppression of type 2 5α–reductase, because it has a much lower affinity for the type 1 isoenzyme. Finasteride suppresses DHT by about 70% in serum and by as much as 85–90% in the prostate. The remaining DHT in the prostate is likely to be the result of type 1 5α–reductase. Suppression of both 5α–reductase isoenzymes with GI198745 result in greater and more consistent suppression of serum dihydrotestosterone than that observed with a selective inhibitor of type 2 5α–reductase. Physiological and clinical studies comparing dual 5α–reductase inhibitors, such as GI198745, with selective type 2, such as finasteride, will be needed to determine the clinical relevance of type 1 5α–reductase within the prostate. Two large international multicenter, phase III trials have been published documenting the safety and efficacy of finasteride in the treatment of human benign prostatic hyperplasia. Combining these two studies, randomized, controlled data are available for 12 months. Noncontrolled extension of these data from a subset of patients, who elected to continue drug treatment for 3, 4 or 5 years, are also available. Long–term medical therapy with finasteride can reduce clinically significant endpoints such as acute urinary retention or surgery. According to the meta–analysis of six randomised clinical trial with finasteride, finasteride is most effective in men with large prostates. A more effective dual inhibitor of type 1 and 2 human 5α–reductase may lower circulating DHT to a greater extent than finasteride and show advantages in the treatment of human benign prostatic hyperplasia and other disease states that depend on DHT.Conclusion:Clinical evaluation of potent dual 5α–reductase inhibitors may help define the relative roles of human type 1 and 2 5α–reductase in the pathophysiology of benign prostatic hyperplasia and other androgen–dependent diseases.

Background:This article summarizes the experience and results of different prostate carcinoma screening projects using total prostate-specific antigen (PSA) and percent free PSA as the initial test. Methods:The twelve projects studied included: (1) a mass screening study using PSA as the initial test in 21,079 volunteers; (2) an investigation of the usefulness of normal and age-referenced PSA cut-offs in 1,618 men; (3) a PSA-based screening study of 2,272 asymptomatic blood donors; (4) an investigation of the evidence and significance of transition zone carcinoma in 340 men with negative digital rectal examination findings; (5) determination of percent free PSA in one retrospective and two prospective studies to determine the appropriate cutpoints for percent free PSA; (6) evaluation of the diagnostic benefit of PSA transition zone density in 308 screening volunteers; (7) a study of the impact of PSA-based screening on the percentage of incidental prostate carcinoma in 1,543 men undergoing transurethral resection of the prostate; (8) an evaluation of the changes in total PSA and pathologic stages in radical prostatectomy over 5 years in a PSA-based mass screening program; (9) a study evaluating the probability of having prostate cancer given the patient’s age, total PSA and digital rectal examination findings; (10) an evaluation of the correlation between preoperative predictors and pathologic features in radical prostatectomy specimens; (11) an investigation of the correlation of total PSA with pathologic stage and tumor volume in patients undergoing radical prostatectomy with low PSA cut-off level, and (12) a study whether age has an impact on the extension of prostate cancer. Results:(1) of the 21,079 volunteers, 1,618 (8%) had elevated PSA levels. Of these men, 778 (48%) underwent biopsies; 197 biopsies were positive for prostate carcinoma and 135 underwent radical prostatectomy. Ninety-five were found to be organ-confined. (2) A PSA cut-off of 2.5 ng/ml in men aged 45–49 years and of 3.5 ng/ml in men aged 50–59 years resulted in an 8% increase in the detection rate of organ-confined disease. (3) Of the 2,272 men, 284 had elevated PSA levels and prostate carcinoma was detected in 62 men. All patients underwent radical prostatectomy and histologic examination revealed organ-confined tumor in all but 8 men. (4) Ninety-eight of 340 men had biopsies positive for carcinoma; 28 of these patients (28.5%) had carcinoma that originated in the transition zone only. (5) In the retrospective study, receiver-operating characteristic curve analysis showed that by using a percent free PSA of 18% as a biopsy criterion, 37% of the negative biopsies could be eliminated although 94% of all carcinomas would still be detected. In the first prospective study, 106 of 158 men with elevated PSA levels <10.0 ng/ml were further evaluated and 37 prostate carcinomas were detected. By using a % free PSA of <22% as a biopsy criterion, 30% of the negative biopsies could be eliminated although 98% of the carcinomas would still be detected. In the second prospective study, 120 of 465 men with total PSA levels between 1.25 and 6.49 ng/ml and a % free PSA <18% were further evaluated and 27 (22.5%) were found to have prostate carcinomas. (6) Receiver-operating characteristic curve analysis for PSA transition zone density showed that by using a PSA transition zone density of >22 ng/ml/cm3 as a biopsy criterion, 24.4% of negative biopsies could be avoided without missing a single carcinoma. (7) In the prescreening era the incidence of T1a grade 1 and 2 carcinomas was 3.1% and the incidence of T1a grade 3 and T1b carcinoma was 2.3% whereas in the years after the establishment of PSA-based screening the incidence was 4.6 and 1.03% respectively. (8) The rate of organ-confined tumors increased from 28.7% in 1993 to 65.7% in 1997. (9) In this evaluation a new approach to proceed with a prostate biopsy based upon the individual risk of having prostate cancer rather than a single PSA cutpoint was developed. (10) High total PSA levels, PSA density and PSA transition zone density correlated significantly with high Gleason scores, capsular penetration, a high percentage of cancer in the prostatectomy specimen and a high cancer volume. (11) In this evaluation all of the 95 patients with PSA levels <3.99 ng/ml who underwent radical prostatectomy showed clinically significant, organ-confined prostate cancer with negative surgical margins. (12) The results of this evaluation suggest that older men have larger tumor volumes compared to younger men with the same PSA levels. Conclusions:These data suggest that PSA-based screening with low PSA cut-off values increase the detection rate of clinically significant, organ-confined and potentially curable prostate cancer. Percent free PSA and PSA transition zone density provide an additional diagnostic benefit over total PSA.

In vitro cultivated fibroblasts derived either from patients with Fanconi's anemia (FA) or from healthy probands were analyzed for their DNA repair‐dependent NAD+ metabolism. No difference in NAD+ pools was found. NAD+ consumption after cell damage by u.v. irradiation was, however, significantly reduced in FA cells. Several FA cell lines had a lowered ability to transfer ADP‐ribose to acid‐precipitable material. Additionally, a decreased activity of NAD: protein ADP‐ribosyltransferase was found for three FA cell lines. Our data indicate, that FA is accompanied by a defective NAD+ metabolism during DNA repair.

ADP-ribosyltransferases from several higher eukaryotes have been purified and characterized, but little is known about ADP-ribosyltransferases in lower eukaryotes. We have purified an ADP-ribosyltransferase (EC 2.4.2.30) from Helix pomatia. The enzyme has an apparent Km of 26.7 microM. Optimal conditions for the enzyme reaction are 17.5 degrees C and pH 8. The time course is linear during the first 10 min of the reaction. The enzyme is capable of poly-ADP-ribosylation. The most highly purified preparation shows one major band at an Mr of 75,000 on electrophoresis in an SDS/polyacrylamide gel, with minor bands at Mr 115,000 and 155,000. Re-activation of SDS/polyacrylamide gels in situ shows the 75,000-Mr band to be enzymically active and additional active bands with Mr values of 115,000, 90,000 and 87,000 respectively. The 115,000-Mr and 75,000-Mr bands cross-react with a polyclonal affinity-purified antiserum against human ADP-ribosyltransferase. Like enzymes from higher eukaryotes, the activity from Helix pomatia is inhibited by thymidine, theophylline, theobromine nicotinamide, 3-methoxybenzamide and 3-aminobenzamide, and is dependent on histone and DNA.

Adrenal androgens are discussed as a reason for tumor progression after androgen ablation therapy. Because of the difference in the secretion of androgens by the adrenals of humans and rats, there is no reliable tumor model to study the role of adrenal androgens in tumor progression. Therefore, the main adrenal androgens were administered to rats in order to mimic human endocrine conditions. Application of dehydroepiandrosteron-sulfate (DHEA-S) alone or a mixture of androstendione (A), 11ß-hydroxyandrostendione (OHA), dehydroepiandrosterone (DHEA), and its sulfate (DHEA-S) to castrated rats caused only a slight increase of prostate and seminal vesicle weights. Contrary to these findings, growth of the R3327 prostatic carcinoma in castrated rats was greatly stimulated by these adrenal androgens up to the level of the intact control. Thus, in spite of androgen ablation, tumor progression could be induced by exogenous adrenal androgens.

The polypeptide growth factors insulin-like growth factor I (IGF-I), epidermal growth factor (EGF), and transforming growth factor-a (TGF-a); second-messenger cyclic adenosine monophosphate (cAMP); protein kinase activators; and neurotransmitters were found to activate the estrogen (ER), progesterone (PR), and glucocorticoid receptor (GR) either in the absence of their natural ligands or synergistically with the respective hormone. There is now evidence of coupling of signaling pathways involving the androgen receptor (AR). Three polypeptide growth factors, IGF-I, keratinocyte growth factor (KGF), and EGF, stimulated AR-mediated reporter-gene transcription in the absence of androgen in DU-145 cells, which were cotransfected with the reporter gene and an AR expression vector. IGF-I effects were observed irrespective of the promoter driving the reporter gene. This growth factor increased the prostate-specific antigen (PSA) level in LNCaP cells, which contain endogenous AR. In CV-1 cells, which transiently express the AR, second-messenger cAMP potentiated effects of testosterone in stimulation of AR-mediated reporter-gene activity. Inhibition of androgen-stimulated chloramphenicol acetyltransferase (CAT) activity in the LNCaP cell line was achieved with retinoic acid. Stimulation and inhibition of prostatic carcinoma cell growth by polypeptide growth factors and cellular regulators may depend on the presence of the AR in an androgen-depleted environment.

Purpose: Transforming growth factors-beta (TGF-beta) are cellular regulators and potent angiogenic factors. We determined serum and urinary levels of TGF-beta 1 and beta 2 in patients with bladder carcinoma to study a correlation with tumor stage, grade and metastatic spread. Materials and Methods: Using commercial immunoassays TGF-beta 1 and beta 2 were determined in serum and urine samples from 57 bladder cancer patients and 18 healthy controls. Results: Serum TGF-beta 1 levels were significantly elevated in 21 patients with invasive bladder cancer (61.5 ng./ml.) compared to 18 healthy controls (36.3 ng./ml.), whereas serum TGF-beta 1 levels in 36 patients with superficial bladder tumors were within the normal range (33.4 ng./ml.). Serum TGF-beta 1 was increased in 27 patients with grade 3 tumors (55.7 ng./ml.), compared to 16 with grade 1 and 14 with grade 2 tumors (32.6 and 33.3 ng./ml., respectively). By contrast, serum TGF-beta 2 levels were not different from those of controls. No significant increase in serum TGF-beta 1 and beta 2 could be found in patients with lymph node metastases. In urine specimens there was no significant correlation of TGF-beta 1 and beta 2 with tumor stage. Conclusions: Our results suggest that elevated serum TGF-beta 1 may be relevant for diagnosis of bladder cancer and further studies are warranted.

This article summarizes the experience and results of different prostate carcinoma screening projects using total prostate specific antigen (PSA) as the initial test and different diagnostic tests to improve specificity. The seven projects studied included 1) a mass screening study using PSA as the initial test in 21,079 volunteers; 2) an investigation of the usefulness of normal and age-referenced PSA cutoffs in 1618 men; 3) a PSA-based screening study of 2272 asymptomatic blood donors; 4) an investigation of the incidence and clinical significance of transitional zone carcinoma in 340 men with negative rectal examination findings and clearly visible prostatic zones on three-dimensional transrectal ultrasound; 5) determination of percent free PSA in one retrospective and two prospective screening studies to define the optimal range of total PSA and determine the appropriate cutpoints for percent free PSA within this range; 6) evaluation of the diagnostic benefit of PSA transitional zone density in 308 screening volunteers; and 7) a study of the impact of PSA-based screening on the percentage of incidental prostate carcinoma diagnosed in 1543 men undergoing transurethal resection of the prostate. 1) Of the 21,078 volunteers, 1618 (8%) had elevated PSA levels. Of these men, 778 (48%) underwent biopsies; 197 biopsies (25%) were positive for prostate carcinoma and 135 patients underwent radical prostatectomy. Ninety-five of the 135 pathologically staged lesions (70%) were found to be organ-confined. 2) A PSA cutoff of 2.5 ng/mL in men age 45-49 years and of 3.5 ng/mL in men age 50-59 years with normal digital rectal examination findings resulted in an 8% increase in both the number of biopsies (66 of 778) and the detection rate of organ-confined disease. 3) Of the 2272 men, 284 had elevated PSA levels and prostate carcinoma was detected in 62 men. All patients underwent radical prostatectomy and histologic examination revealed organ-confined disease in all but eight men. 4) Ninety-eight of 340 men (28.8%) had biopsies positive for carcinoma; 28 of these patients (28.5%) had carcinoma that originated in the transitional zone only. 5) In the retrospective study, receiver operating characteristic curve analysis showed that by using a percent free PSA of 18% as a biopsy criterion in men with an elevated PSA serum level, 37% of the negative biopsies could be eliminated although 94% of all carcinomas would still be detected. In the first prospective study, 106 of 158 men with elevated total PSA values between 2.5 and 10.0 ng/mL were further evaluated and 37 prostate carcinomas were detected. By using a percent free PSA of ≤22% as a biopsy criterion, 30% of the negative biopsies could be eliminated although 98% of the carcinomas would still be detected. In the second prospective study, 120 of 465 men with total PSA levels between 1.25 and 6.49 ng/mL, a percent free PSA of &lt;18%, and normal digital rectal examination findings were further evaluated and 27 (22.5%) were found to have prostate carcinoma. 6) Receiver operating characteristic curve analysis for PSA transitional zone density showed that by using a PSA transitional zone density of >0.22 ng/mL/cc as a biopsy criterion, 24.4% of negative biopsies could be avoided without missing the detection of a single carcinoma. 7) In the prescreening era the incidence of T1a Grade 1 and 2 carcinomas was 3.1% and the incidence of T1a Grade 3 and T1b carcinoma was 2.3%, whereas in the years after the establishment of PSA-based screening the incidence was 4.6% and 1.03%, respectively. These data suggest that PSA-based screening increases the detection rate of clinically significant and organ-confined tumors. Percent free PSA and PSA transitional zone density provide an additional diagnostic benefit over total PSA. Cancer 1997; 80:1818-29. © 1997 American Cancer Society.

Reifenstein syndrome is an eponymic term that describes partial androgen-insensitive disorders. Androgen receptor isolated from five patients with this syndrome contains a specific mutation in the DNA binding domain of the receptor. This mutation converts an alanine to a threonine at position 596 next to the zinc catenation site at the second finger. The threonine 596 mutant receptor mediated normal androgen response at promoters with closely positioned multiple regulatory elements for the androgen receptor and other transcription factors. Promoters with single isolated androgen response elements were not transactivated by the mutant receptor. In in vitro receptor-DNA binding studies, interaction with DNA by the mutant receptor was achieved only in the presence of an anti-androgen receptor antibody. Exchanging alanine 596 in the wild-type androgen receptor with serine or valine produced mutants with properties indistinguishable from those of the naturally occurring threonine 596 mutant receptor. These results indicate that an alanine residue at position 596 contributes important structural and functional activities to the androgen receptor. In the androgen receptor from the patients with Reifenstein syndrome, in which this alanine is converted to a threonine, wild-type receptor properties can be restored by exchanging an additional threonine at position 602 to an alanine. An alanine residue at position 596 or 602 in the DNA binding domain of the androgen receptor is therefore important for the full function of this receptor. In all steroid receptors that bind the core sequence AGAACANNNTGTTCT, an alanine residue is also present at a position equivalent to alanine 596 in the androgen receptor.

In the prostate, androgen action affects the growth of the gland, its morphology, and regulation of protein expression. Endocrine therapy of non-organ-confined tumors is based on the androgen dependence of the vast majority of prostatic carcinomas. Although initial response rates are high, this therapy is only temporarily effective. Critical molecular changes ultimately resulting in androgen independence of tumor cells are unknown at this time. The androgen signal-transduction cascade and its central element, the androgen receptor (AR), are possible targets for such changes. Immunohistological analysis using anti-AR antibodies has revealed the presence of AR in a vast majority of therapy-responsive as well as therapy-unresponsive prostatic carcinomas, indicating that loss of AR expression is not the reason for androgen independence. On the other hand, molecular-biology studies have revealed qualitative and quantitative impairment of AR expression in prostatic tumor cell lines that represent very late stages of prostatic carcinoma development. Mutant ARs were detected in the prostatic tumor cell line LNCaP and in two specimens from primary prostatic tumors. The LNCaP mutant AR as well as mutant AR715met, one of the mutant receptors detected in tumor tissue, show a gain of function as compared with the wild-type receptor. In addition to androgens, the natural activators of the AR, the LNCaP receptor is activated also by progestagenic and estrogenic steroids and by the nonsteroidal antiandrogen flutamide. AR715met is activated by adrenal androgens and progesterone in addition to androgens. Although determination of the frequency of point mutations in late prostatic carcinoma requires further investigation, these data imply that tumor progression in an androgen-ablated environment may be accompanied by aberrant AR activation.

In vitro cultivated fibroblasts derived either from patients with Fanconi's anemia (FA) or from healthy probands were analyzed for their DNA repair‐dependent NAD+ metabolism. No difference in NAD+ pools was found. NAD+ consumption after cell damage by u.v. irradiation was, however, significantly reduced in FA cells. Several FA cell lines had a lowered ability to transfer ADP‐ribose to acid‐precipitable material. Additionally, a decreased activity of NAD: protein ADP‐ribosyltransferase was found for three FA cell lines. Our data indicate, that FA is accompanied by a defective NAD+ metabolism during DNA repair.

We previously detected elevated transforming growth factor beta-1 (TGF-beta1) serum levels in patients with invasive bladder carcinomas. In this study, we therefore investigated whether elevated serum levels correlate with enhanced TGF-beta expression in human bladder tumours. mRNA levels of TGF-beta1, -beta2 and -beta3 were reduced in bladder tumour tissue to 86%, 68% and 56%, respectively, of the levels in normal urothelium. On the other hand, TGF-beta1 protein levels were found to be higher in superficial tumours (Ta-T1) (mean level of 0.153 ng mg(-1)) and in invasive T2/T3 tumours (mean level of 0.104 ng mg(-1)) compared with normal urothelium (mean level of 0.065 ng mg(-1)). Invasive T4 tumours, however, contained only low amounts of TGF-beta1 (mean level of 0.02 ng mg(-1)). Neither in mean nor in individual patients were serum and tissue TGF-beta levels correlated with each other. Cell culture experiments on primary bladder cells revealed a 57% decrease in TGF-beta1 mRNA levels in tumour compared with normal epithelial cells. Tumour epithelial cells contained about two times higher levels of TGF-beta2 and TGF-beta3 mRNA than normal epithelial cells. Fibroblasts expressed about the same amount of TGF-beta1 or TGF-beta2 as epithelial cells. Yet, fibroblasts released only 19% and 13% of the amount secreted by tumour epithelial cells into the supernatant. TGF-beta3, on the other hand, was expressed by fibroblasts with higher levels than by epithelial cells. TGF-beta1 was the predominent isoform in bladder tissue and cells at protein as well as on mRNA levels indicating that TGFs-beta2 and -beta3 are of minor importance in bladder cancer. In summary, there is a lack of correlation between TGF-beta serum levels and TGF-beta expression in tumour tissue in bladder cancer.

Proliferative and secretory responses in androgen-sensitive prostate cancer LNCaP cells are regulated by steroid and peptide hormones and by differentiation-promoting substances. In the present study, we evaluated whether peripheral blood monocytes that exhibit anti-tumour activity in haematopoietic and solid tumours influence growth and secretion in the LNCaP cell line. For this purpose, LNCaP cells were incubated with monocyte-conditioned medium (MCM), and proliferation as well as expression of androgen receptor (AR) and secretion of prostate-specific antigen (PSA) were assessed. Conditioned medium from monocytes reduced proliferation in a dose-dependent manner. Incubation with 40% MCM caused a 50% reduction in cell proliferation. AR protein decreased by 70% and PSA levels in supernatants from LNCaP cells were reduced by approximately 80% following treatment with MCM. We focused on the contribution of two major products of activated monocytes, prostaglandin E2 and interleukin 1beta (IL-1beta), to the MCM modulatory action. LNCaP cells treated with prostaglandin E2 showed neither a reduction in proliferation nor a down-regulation of AR and PSA levels. The effects of MCM on cellular proliferation, AR protein and PSA secretion were abolished by pretreatment of MCM with a neutralizing anti-IL-1beta antibody. In addition, recombinant IL-1beta was able to replace MCM for the inhibition of proliferation and down-regulation of AR and PSA proteins. LNCaP cells were shown to express the IL-1beta receptor type 1, which transduces IL-1beta signal. Our findings reveal that monocyte-derived IL-1beta inhibits the proliferation of androgen-responsive prostate tumour cells and reduces AR and PSA levels.

Purpose: We evaluate the predictive values of total and percent free prostate specific antigen (PSA) in regard to high grade intraepithelial lesions in volunteers who participated in the Tyrol PSA Screening Project. Materials and Methods: Between June 1995 and December 1998, 1,474 patients undergoing transrectal biopsy of the prostate were evaluated. The primary detection rates of prostate cancer and high grade intraepithelial lesions were evaluated. In addition, the rate of prostate cancer detected on biopsy in patients diagnosed with high grade prostatic intraepithelial neoplasia on the previous biopsy was assessed. Mean total PSA values and mean percent free PSA levels were determined for each study group and compared using the Mann-Whitney U test. Results: A total of 1,077 (73.1%) volunteers had benign prostatic hyperplasia or prostatitis, and 327 (22.2%) had prostate cancer. The primary detection rate for high grade intraepithelial lesions was 4.7% (70 patients) and on repeat biopsy was 38.6% (27). Mean total PSA for the benign prostatic hyperplasia, prostate cancer, high grade and intraepithelial cancer groups were 6.0, 8.7, 5.9 and 5.2 ng./ml., respectively. Mean percent free PSA values for the various groups were 21.9, 12.1, 15.0 and 12.0, respectively. In regard to total PSA there was a statistically significant difference between the prostate cancer and high grade prostatic intraepithelial neoplasia groups (p = 0.016), as well as the prostate cancer and intraepithelial cancer groups (p = 0.028). However, the high grade and intraepithelial cancer groups did not differ significantly. In regard to percent free PSA there were statistically significant differences between the prostate cancer and high grade prostatic intraepithelial neoplasia groups (p = 0.0001), and the high grade and intraepithelial cancer groups (p = 0.013). Conclusions: In regard to percent free PSA our data indicate a significant difference between high grade intraepithelial lesion and intraepithelial cancer. Due to a substantial overlap in percent free prostate specific antigen between the 2 groups, a clinically useful cutoff point could not be established. Therefore, we recommend repeat biopsy in all patients with high grade intraepithelial lesions regardless of the percent free PSA.