[en] Published in summary form only

[en] In normal prostate epithelium the TMPRSS2 gene encoding a type II serine protease is directly regulated by male hormones through the androgen receptor. In prostate cancer ERG protooncogene frequently gains hormonal control by seizing gene regulatory elements of TMPRSS2 through genomic fusion events. Although, the androgenic activation of TMPRSS2 gene has been established, little is known about other elements that may interact with TMPRSS2 promoter sequences to modulate ERG expression in TMPRSS2-ERG gene fusion context. Comparative genomic analyses of the TMPRSS2 promoter upstream sequences and pathway analyses were performed by the Genomatix Software. NKX3.1 and ERG genes expressions were evaluated by immunoblot or by quantitative Real-Time PCR (qRT-PCR) assays in response to siRNA knockdown or heterologous expression. QRT-PCR assay was used for monitoring the gene expression levels of NKX3.1-regulated genes. Transcriptional regulatory function of NKX3.1 was assessed by luciferase assay. Recruitment of NKX3.1 to its cognate elements was monitored by Chromatin Immunoprecipitation assay. Comparative analysis of the TMPRSS2 promoter upstream sequences among different species revealed the conservation of binding sites for the androgen inducible NKX3.1 tumor suppressor. Defects of NKX3.1, such as, allelic loss, haploinsufficiency, attenuated expression or decreased protein stability represent established pathways in prostate tumorigenesis. We found that NKX3.1 directly binds to TMPRSS2 upstream sequences and negatively regulates the expression of the ERG protooncogene through the TMPRSS2-ERG gene fusion. These observations imply that the frequently noted loss-of-function of NKX3.1 cooperates with the activation of TMPRSS2-ERG fusions in prostate tumorigenesis

[en] Highlights: • Ternary classification models based on known hormonal activities’ chemicals were developed. • Both of the optimum models for AR and TR was support vector machines (SVM). • A system for identifying different hormone activities was constituted. Endocrine disrupting chemicals (EDCs) can exhibit adverse effects by increasing or blocking hormonal activities as agonists or antagonists through nuclear receptors. Computational toxicology research provides a fast and automated screening tool for determining the potential effects of EDCs. Here, we collected a large dataset of known hormonal activities to develop ternary classification models of androgen receptor (AR) and thyroid hormone receptor (TR), in combination linear discriminant analysis (LDA), classification and regression trees (CART), and support vector machines (SVM). The optimum model for classifying AR and TR activities was SVM. These newly developed models constitute a rapidly systematic early-warning technical system for identifying different hormone activities.

[en] Background: We studied whether hormonal therapy, (neo)adjuvant to radiotherapy for localized prostate cancer, is related to an increase in depression and whether this is caused by the hormonal therapy itself or by the relatively poor prognosis of patients who get (neo)adjuvant hormonal therapy. Methods: Between 2002 and 2005, 288 patients, irradiated for prostate cancer (T1-3N0M0), were studied prospectively in two clinics. In one clinic almost all patients received (neo)adjuvant androgen deprivation (Bicalutamide + Gosereline). In a second clinic hormonal therapy was prescribed mainly for high risk patients. This allowed us to separate the effects of hormonal therapy and the patient's prognosis. Results: During the course of hormonal therapy, depression was significantly heightened by both hormone use (p < 0.001) and poor prognosis (p < 0.01). After completion of hormonal therapy, poor prognosis continued to affect the depression score (p < 0.01). The increase was, however, small. Conclusions: Depression was mildly increased in patients receiving hormonal therapy. The increase appeared to be related to both the hormone therapy itself and the high risk status of patients. High risk status, with the associated poor prognosis, had a more sustained effect on depression. The rise was statistically significant, but was too small, however, to bear clinical significance.

[en] Purpose: Radiation Therapy Oncology Group 85-31 was a randomized trial comparing radiotherapy (RT) alone vs. RT plus adjuvant androgen suppression for life in unfavorable-prognosis carcinoma of the prostate. We examined the impact of early initiation of salvage hormonal therapy (HT) in relapsing patients randomized to RT alone arm. Methods and Materials: Patients were divided into two groups: early salvage HT and late salvage HT. The early salvage group was defined as receiving HT with a prostate-specific antigen (PSA) level of less than 10 ng/mL, and the late salvage HT group had a PSA level of 10 ng/mL or greater. The outcomes were overall survival (OS), cause-specific mortality (CSM), and local failure (LF). The Kaplan-Meier estimation and log-rank test were used for OS, and the cumulative incidence estimation and Gray's test were used for CSM and LF. Proportional hazards regression models were used to compare the outcomes adjusted for other covariates. Results: The median follow-up times of surviving patients in the early and late salvage HT groups were about 11 and 13 years, respectively. The late salvage HT group had significantly more post-prostatectomy patients and patients with high Gleason scores. After adjustment for all covariates, OS was significantly longer in the early salvage HT group (hazard ratio, 1.5; p = 0.01). However, there were no statistically significant differences in LF or CSM between the groups. Conclusions: The early introduction of salvage HT resulted in improved OS but not improved CSM and LF. A randomized trial to define the optimal salvage hormonal timing is warranted in this group of patients with PSA recurrence after RT.

[en] Highlights: • TSG101interacts with AR and recruits AR to its associated late endosome structure. • TSG101 overexpression reduces AR protein level and its transactivation activity. • The downregulation of AR is mediated by TSG101 through lysosomal degradation. The androgen receptor (AR) signaling pathway plays a vital role in the normal development and function of the male reproductive organs. Dysregulation of the androgen-AR signaling pathway has been linked to prostate cancer. Here, we demonstrate that tumor susceptibility gene 101 (TSG101) regulates AR expression level via the endosome/lysosome degradation pathway. In LNCaP cells, TSG101 overexpression recruits the AR to TSG101-containing cytoplasmic vesicles resulting in reduced AR protein level and AR transactivation activity downregulation. Immunofluorescence microscopy demonstrated that TSG101-decorated cytoplasmic vesicles are associated with late endosomes/lysosomes and the AR could be found within the Lamp2 positive TSG101 vesicles upon lysosomal protease inhibitor treatment. Furthermore, chloroquine or bafilomycin A1 treatment was able to restore TSG101-mediated AR expression reduction. Based on these data, we conclude that the interaction of the AR and TSG101 leads to AR recruitment to TSG101-containing cytoplasmic vesicles and induces AR-attenuated expression through the late endosome/lysosome degradation pathway.

[en] Purpose: Trial RTOG 9202 was a phase 3 randomized trial designed to determine the optimal duration of androgen deprivation therapy (ADT) when combined with definitive radiation therapy (RT) in the treatment of locally advanced nonmetastatic adenocarcinoma of the prostate. Long-term follow-up results of this study now available are relevant to the management of this disease. Methods and Materials: Men (N=1554) with adenocarcinoma of the prostate (cT2c-T4, N0-Nx) with a prostate-specific antigen (PSA) <150 ng/mL and no evidence of distant metastasis were randomized (June 1992 to April 1995) to short-term ADT (STAD: 4 months of flutamide 250 mg 3 times per day and goserelin 3.6 mg per month) and definitive RT versus long-term ADT (LTAD: STAD with definitive RT plus an additional 24 months of monthly goserelin). Results: Among 1520 protocol-eligible and evaluable patients, the median follow-up time for this analysis was 19.6 years. In analysis adjusted for prognostic covariates, LTAD improved disease-free survival (29% relative reduction in failure rate, P<.0001), local progression (46% relative reduction, P=.02), distant metastases (36% relative reduction, P<.0001), disease-specific survival (30% relative reduction, P=.003), and overall survival (12% relative reduction, P=.03). Other-cause mortality (non–prostate cancer) did not differ (5% relative reduction, P=.48). Conclusions: LTAD and RT is superior to STAD and RT for the treatment of locally advanced nonmetastatic adenocarcinoma of the prostate and should be considered the standard of care.

[en] Androgen ablation has been the cornerstone of treating prostate cancers that have spread beyond the confines of the gland for over 50 years. It is achieved surgically by removal of the testes, or medically with gonadotropin releasing hormone (GnRH) analogues, exogenous estrogens, anti-androgens or adrenal enzyme synthesis inhibitors. Despite this long clinical experience, controversies remain as to when androgen ablation should be initiated - early vs. late; whether the simultaneous ablation of testicular and adrenal androgens should be considered 'standard' therapy; how long to continue treating patients who are responding - until progression or in an 'off and on' or 'intermittent' fashion; and, the value of changing in hormone treatments in patients who have failed primary therapy. In general, the duration of response to first line therapy ranges from 12-18 months although upwards of 20% of patients show no biochemical or clinical evidence of relapse within 5 year follow-up. The toxicities include hot flashes, a loss of libido, impotence, fatigue, gynecomastia, softening of the skin and beard, loss of muscle tone and personality changes. Treatment with anti-androgens such as flutamide, casodex or nilutamide alone, which do not lower serum testosterone levels, are similar in toxicities except for a lower frequency of impotence. However, in several studies, anti-androgen monotherapy has been shown to be inferior to those that lower serum testosterone levels. Our general approach is to offer combined androgen blockade as initial treatment and to monitor the patient serially. Those who show a normalization of PSA have a good prognosis, while those who do not are considered for alternative therapies

[en] Purpose: To assess whether the PSA response to neoadjuvant androgen deprivation therapy (ADT) is associated with biochemical control in men treated with radiation therapy (RT) for prostate cancer. Methods and Materials: In a cohort of men treated with curative-intent RT for localized prostate cancer between 1988 and 2005, 117 men had PSA values after the first and second months of neoadjuvant ADT. Most men had intermediate-risk (45%) or high-risk (44%) disease. PSA halving time (PSAHT) was calculated by first order kinetics. Median RT dose was 76 Gy and median total duration of ADT was 4 months. Freedom from biochemical failure (FFBF, nadir + 2 definition) was analyzed by PSAHT and absolute PSA nadir before the start of RT. Results: Median follow-up was 45 months. Four-year FFBF was 89%. Median PSAHT was 2 weeks. A faster PSA decline (PSAHT ≤2 weeks) was associated with greater FFBF (96% vs. 81% for a PSAHT >2 weeks, p = 0.0110). Those within the fastest quartile of PSAHTs (≤ 10 days) achieved a FFBF of 100%. Among high-risk patients, a PSAHT ≤2 weeks achieved a 4-yr FFBF of 93% vs. 70% for those with PSAHT >2 weeks (p = 0.0508). Absolute PSA nadir was not associated with FFBF. On multivariable analysis, PSAHT (p = 0.0093) and Gleason score (p = 0.0320) were associated with FFBF, whereas T-stage (p = 0.7363) and initial PSA level (p = 0.9614) were not. Conclusions: For men treated with combined ADT and RT, PSA response to the first month of ADT may be a useful criterion for prognosis and treatment modification.

[en] Background and Aim: Androgen plays a fundamental role in the growth and differentiation of prostate. Androgen receptor (AR) expression may represent a potential marker of prognosis in prostate cancer. However, there have been variable results regarding its ability to predict clinical progression. Despite the oncogenic properties of DJ-1, its significance in prostate cancer development and progression is not well understood. This research shed some light on the possible role of immunohistochemical expression of DJ-1 in clinically localized prostatic carcinoma in relation to the established role of AR and other clinico pathologic parameters. Materials and Methods: The immunohistochemical expression of AR and DJ-1 was evaluated in 129 samples including benign hyperplasia (n = 60) and prostatic carcinoma (n = 69). Results: The mean value of AR immunostaining was significantly higher in prostatic carcinomas than in benign hyperplasia (P = 0.001). A significant inverse correlation was found between AR immunostaining and the grade of prostatic carcinomas. A significantly higher median DJ-1 score was found in prostatic carcinoma than in benign hyperplasia (P = 0.0001). There was a significant direct correlation between AR and DJ-1 score (P = 0.0001). AR is more sensitive in predicting prostatic carcinoma than DJ-1 but DJ-1 is more specific than AR. Conclusion: AR nuclear expression was consistently present in benign and adenocarcinoma epithelium. But, there may be limited clinical use for AR expression in localized carcinoma due to its constant heterogeneity. DJ-1 with its oncogenic properties, specificity for prostatic carcinoma and homogenous expression gives an ideal complementary role to AR in the detection and treatment of prostatic carcinomas.