Nuclear mTOR acts as a transcriptional integrator of the androgen signaling pathway in prostate cancer.

Androgen receptor (AR) signaling reprograms cellular metabolism to support prostate cancer (PCa) growth and survival. Another key regulator of cellular metabolism is mTOR, a kinase found in diverse protein complexes and cellular localizations, including the nucleus. However, whether nuclear mTOR plays a role in PCa progression and participates in direct transcriptional cross-talk with the AR is unknown. Here, via the intersection of gene expression, genomic, and metabolic studies, we reveal the existence of a nuclear mTOR-AR transcriptional axis integral to the metabolic rewiring of PCa cells. Androgens reprogram mTOR-chromatin associations in an AR-dependent manner in which activation of mTOR-dependent metabolic gene networks is essential for androgen-induced aerobic glycolysis and mitochondrial respiration. In models of castration-resistant PCa cells, mTOR was capable of transcriptionally regulating metabolic gene programs in the absence of androgens, highlighting a potential novel castration resistance mechanism to sustain cell metabolism even without a functional AR. Remarkably, we demonstrate that increased mTOR nuclear localization is indicative of poor prognosis in patients, with the highest levels detected in castration-resistant PCa tumors and metastases. Identification of a functional mTOR targeted multigene signature robustly discriminates between normal prostate tissues, primary tumors, and hormone refractory metastatic samples but is also predictive of cancer recurrence. This study thus underscores a paradigm shift from AR to nuclear mTOR as being the master transcriptional regulator of metabolism in PCa.

A DNA copy number alteration classifier as a prognostic tool for prostate cancer patients.

BACKGROUND: Distinguishing between true indolent and potentially life-threatening prostate cancer is challenging in tumours displaying clinicopathologic features associated with low or intermediate risk of relapse. Several somatic DNA copy number alterations (CNAs) have been identified as potential prognostic biomarkers, but the standard cytogenetic method to assess them has a limited multiplexing capability. METHODS: Multiplex ligation-dependent probe amplification (MLPA) targeting 14 genes was optimised to survey 448 tumours of patients with low or intermediate risk (Grade Group 1-3, Gleason score ≤7) who underwent radical prostatectomy. A 6-gene CNA classifier was developed using random survival forest and Cox proportional hazard modelling to predict biochemical recurrence. RESULTS: The classifier score was significantly associated with biochemical recurrence after adjusting for standard clinicopathologic variables and the known prognostic index CAPRA-S score with a hazard ratio of 2.17 and 1.80, respectively (n = 406, P < 0.01). The prognostic value of this classifier was externally validated in published CNA data from three radical prostatectomy cohorts and one radiation therapy pre-treatment biopsy cohort. CONCLUSION: The 6-gene CNA classifier generated by a single MLPA assay compatible with the small quantities of DNA extracted from formalin-fixed paraffin-embedded (FFPE) tissue specimens has the potential to improve the clinical management of patients with low or intermediate risk disease.

OXIDATIVE STRESS AND REPRODUCTIVE FUNCTION: The protection of mammalian spermatozoa against oxidative stress.

In brief: This review focuses on the enzymatic antioxidant mechanisms to fight oxidative stress by spermatozoa, highlighting the differences among mammalian species. We discuss recent evidence about players that promote and fight oxidative stress and the need for novel strategies to diagnose and treat cases of male infertility associated with oxidative damage of the spermatozoon. Abstract: The spermatozoon is very sensitive to high reactive oxygen species (ROS) levels due to its limited antioxidant system. A consortium of antioxidant enzymes, including superoxide dismutase (SOD), glutathione peroxidases (GPXs), peroxiredoxins (PRDXs), thioredoxins, and glutathione-S-transferases, is necessary to produce healthy spermatozoa and to maintain sperm quality to ensure motility, capacitation, and DNA integrity. A delicate balance between ROS production and antioxidant enzymes is needed to ensure ROS-dependent sperm capacitation. GPX4 is an essential component of the mitochondrial sheath in mammalian spermatozoa, and GPX5 is a crucial antioxidant defence in the mouse epididymis to protect the sperm genome during the maturation of the spermatozoon. The mitochondrial superoxide (O2·-) production is controlled by SOD2, and the hydrogen peroxide (H2O2) generated by SOD2 activity and peroxynitrite (ONOO-) are scavenged mainly by PRDXs in human spermatozoa. PRDXs regulate the redox signalling necessary for sperm motility and capacitation, particularly by PRDX6. This enzyme is the first line of defence against oxidative stress to prevent lipid peroxidation and DNA oxidation by scavenging H2O2 and ONOO- through its peroxidase activity and repairing oxidized membranes by its calcium-independent phospholipase A2 activity. The success of antioxidant therapy in treating infertility resides in the proper diagnosis of the presence of oxidative stress and which type of ROS are produced. Thus, more research on the molecular mechanisms affected by oxidative stress, the development of novel diagnostic tools to identify infertile patients with oxidative stress, and randomized controlled trials are of paramount importance to generate personalized antioxidant therapy to restore male fertility.

A three-gene DNA methylation biomarker accurately classifies early stage prostate cancer.

BACKGROUND: We identify and validate accurate diagnostic biomarkers for prostate cancer through a systematic evaluation of DNA methylation alterations. MATERIALS AND METHODS: We assembled three early prostate cancer cohorts (total patients = 699) from which we collected and processed over 1300 prostatectomy tissue samples for DNA extraction. Using real-time methylation-specific PCR, we measured normalized methylation levels at 15 frequently methylated loci. After partitioning sample sets into independent training and validation cohorts, classifiers were developed using logistic regression, analyzed, and validated. RESULTS: In the training dataset, DNA methylation levels at 7 of 15 genomic loci (glutathione S-transferase Pi 1 [GSTP1], CCDC181, hyaluronan, and proteoglycan link protein 3 [HAPLN3], GSTM2, growth arrest-specific 6 [GAS6], RASSF1, and APC) showed large differences between cancer and benign samples. The best binary classifier was the GAS6/GSTP1/HAPLN3 logistic regression model, with an area under these curves of 0.97, which showed a sensitivity of 94%, and a specificity of 93% after external validation. CONCLUSION: We created and validated a multigene model for the classification of benign and malignant prostate tissue. With false positive and negative rates below 7%, this three-gene biomarker represents a promising basis for more accurate prostate cancer diagnosis.

The combination of PTEN deletion and 16p13.3 gain in prostate cancer provides additional prognostic information in patients treated with radical prostatectomy.

Prostate cancer is a clinically heterogeneous disease and accurately risk-stratifying patients is a key clinical challenge. We hypothesized that the concurrent identification of the DNA copy number alterations 10q23.3 (PTEN) deletion and 16p13.3 (PDPK1) gain, related to the PI3K/AKT survival pathway, would improve prognostication. We assessed PTEN deletion status using fluorescence in situ hybridization (FISH) and evaluated its clinical significance in combination with the 16p13.3 gain in a set of 332 primary radical prostatectomy cases on a tissue microarray with clinical follow-up. The PTEN deletion was detected in 34% (97/287) of the evaluable tumors and was significantly associated with high Gleason grade group (P < 0.0001) and advanced pathological tumor stage (pT-stage, P < 0.001). The PTEN deletion emerged as a significant predictor of biochemical recurrence independent of the standard clinicopathologic parameters (hazard ratio: 3.00, 95% confidence interval: 1.81-4.98; P < 0.0001) and further stratified patients with low and intermediate risk of biochemical recurrence [Gleason grade group 1-2 (≤3 + 4), Gleason grade group 2 (3 + 4), pT2, prostate-specific antigen ≤ 10, low and intermediate CAPRA-S score; log-rank P ≤ 0.007]. A PTEN deletion also increased the risk of distant metastasis (log-rank, P = 0.001), further supporting its role in prostate cancer progression. Combining both 16p13.3 gain and PTEN deletion improved biochemical recurrence risk stratification and provided prognostic information beyond the established CAPRA-S score (co-alteration: hazard ratio: 4.70, 95% confidence interval: 2.12-10.42; P < 0.0001). Our study demonstrates the potential clinical utility of PTEN genomic deletion in low-intermediate risk patients and highlights the enhanced prognostication achieved when assessed in combination with another genomic biomarker related to the PI3K/AKT pathway, thereby supporting their promising usefulness in clinical management of prostate cancer.

Optimization of the 2014 Gleason grade grouping in a Canadian cohort of patients with localized prostate cancer.

OBJECTIVES: To evaluate the five-tier Gleason grade group (GG) scoring of prostate cancers adopted by the International Society of Urology Pathology (ISUP) in 2014, and to propose modifications to optimize its performance. PATIENTS AND METHODS: Data were obtained from PROCURE, a prospective cohort of patients with localized prostate cancer undergoing radical prostatectomy in Québec, 2006-2013. Surgical specimens were evaluated by genitourinary pathologists using 2014 ISUP criteria. Treatment failure was defined as biochemical recurrence and/or initiation of secondary, non-adjuvant therapy. Analyses were conducted using Kaplan-Meier methods, log-rank tests, Cox proportional hazards models and Harrell's concordance indices. RESULTS: A total of 1 917 patients were included, with a median follow-up of 69 months. The 5-year treatment failure rates were 9.6%, 23.5%, 43.1%, 52.6% and 84.3% in GG1-5, respectively (P < 0.001 when comparing GG2 with GG3). Treatment failure rates for patients in GG2 and GG3 with tertiary Gleason 5 pattern were higher than patients in the same group without a tertiary pattern (P < 0.001), but were similar to rates for patients in GGs 3 or 4 without a tertiary pattern (P > 0.3). Primary Gleason pattern (4/5) predicted treatment failure in GG5 (5-year failure rates 82.3% vs 97.1%, respectively; P = 0.001). The five-tier GG system had greater accuracy as a prognostic indicator compared with the four-tier system (Harrell's concordance index 0.716 vs 0.676). When upgrading patients in GG2/3 with tertiary Gleason 5 pattern to patients in GG3/4, and separating patients in GG5 by primary Gleason pattern, the Harrell's concordance index increased to 0.730. CONCLUSION: The five-tier GG system increased accuracy for predicting treatment failure compared with the previous grading systems, but can be further improved.

The relationship between body-mass index, physical activity, and pathologic and clinical outcomes after radical prostatectomy for prostate cancer.

PURPOSE: We evaluated whether an increased body-mass index (BMI) and decreased physical activity increase the risk of locally advanced or high-risk prostate cancer (PCa) at radical prostatectomy (RP), and treatment failure after surgery. METHODS: Data were collected from the PROCURE Biobank, a prospective cohort of patients with localized PCa undergoing RP in four academic centers in Québec between 2006 and 2013. Treatment failure was defined as biochemical recurrence and/or initiation of secondary, non-adjuvant therapy, and analyzed using the Kaplan-Meier method, log-rank tests, and Cox proportional-hazards models. Uni- and multivariate (ordered) logistic regression was used for time-independent variables. RESULTS: 1813 patients were included. Median follow-up time was 69 months. Patients who reported a lower BMI were generally older, of Asian descent, and physically more active (p < 0.05). Younger, black, and overweight/obese patients reported less physical activity (p < 0.05). In multivariate analyses, a higher BMI increased the risk for locally advanced, high-risk PCa (defined as a pT3, N1 and/or Gleason 8-10 tumor; odds ratio 1.33, p < 0.001), but increased physical activity did not predict high-risk disease (odds ratio 0.84, p = 0.39). Patients with a higher BMI also had a larger prostate at surgery (odds ratio 1.13, p = 0.03). BMI and physical activity were not associated with positive surgical margins or time to treatment failure (p > 0.05). CONCLUSIONS: BMI was an independent predictor for locally advanced, high-risk disease in this cohort of PCa patients undergoing RP, but was unrelated to treatment failure. Physical activity was not related to locally advanced, high-risk PCa or treatment failure.

Improving ultrasound-based prostate volume estimation.

BACKGROUND: To define a new coefficient to be used in the formula (Volume = L x H x W x Coefficient) that better estimates prostate volume using dimensions of fresh prostates from patients who had transrectal ultrasound (TRUS) imaging prior to prostatectomy. METHODS: The prostate was obtained from 153 patients, weighed and measured to obtain length (L), height (H), and width (W). The density was determined by water displacement to calculate volume. TRUS data were retrieved from patient charts. Linear regression analyses were performed to compare various prostate volume formulas, including the commonly used ellipsoid formula and newly introduced bullet-shaped formula. RESULTS: By relating measured prostate volumes from fresh prostates to TRUS-estimated prostate volumes, 0.66 was the best fitting coefficient in the (L x H x W x Coefficient) equation. This newfound coefficient combined with outlier removal yielded a linear equation with an R2 of 0.64, compared to 0.55 and 0.60, for the ellipsoid and bullet, respectively. By comparing each of the measured vs. estimated dimensions, we observed that the mean prostate height and length were overestimated by 11.1 and 10.8% using ultrasound (p < 0.05), respectively, while the mean width was similar (p > 0.05). Overall, the ellipsoid formula underestimates prostate volumes by 18%, compared to an overestimation of 4.6 and 5.7% for the bullet formula and the formula using our coefficient, respectively. CONCLUSIONS: This study defines, for the first time, a coefficient based on freshly resected prostates as a reference to estimate volumes by imaging. Our findings support a bullet rather than an ellipsoid prostate shape. Moreover, substituting the coefficient commonly used in the ellipsoid formula by our calculated coefficient in the equation estimating prostate volume by TRUS, provides a more accurate value of the true prostate volume.

Asporin is a stromally expressed marker associated with prostate cancer progression.

BACKGROUND: Prostate cancer shows considerable heterogeneity in disease progression and we propose that markers expressed in tumour stroma may be reliable predictors of aggressive tumour subtypes. METHODS: We have used Kaplan-Meier, univariate and multivariate analysis to correlate the expression of Asporin (ASPN) mRNA and protein with prostate cancer progression in independent cohorts. We used immunohistochemistry and H scoring to document stromal localisation of ASPN in a tissue microarray and mouse prostate cancer model, and correlated expression with reactive stroma, defined using Masson Trichrome staining. We used cell cultures of primary prostate cancer fibroblasts treated with serum-free conditioned media from prostate cancer cell lines to examine regulation of ASPN mRNA in tumour stromal cells. RESULTS: We observed increased expression of ASPN mRNA in a data set derived from benign vs tumour microdissected tissue, and a correlation with biochemical recurrence using Kaplan-Meier and Cox proportional hazard analysis. ASPN protein localised to tumour stroma and elevated expression of ASPN was correlated with decreased time to biochemical recurrence, in a cohort of 326 patients with a median follow up of 9.6 years. Univariate and multivariate analysis demonstrated that ASPN was correlated with progression, as were Gleason score, and clinical stage. Additionally, ASPN expression correlated with the presence of reactive stroma, suggesting that it may be a stromal marker expressed in response to the presence of tumour cells and particularly with aggressive tumour subtypes. We observed expression of ASPN in the stroma of tumours induced by p53 inhibition in a mouse model of prostate cancer, and correlation with neuroendocrine marker expression. Finally, we demonstrated that ASPN transcript expression in normal and cancer fibroblasts was regulated by conditioned media derived from the PC3, but not LNCaP, prostate cancer cell lines. CONCLUSIONS: Our results suggest that ASPN is a stromally expressed biomarker that correlates with disease progression, and is observed in reactive stroma. ASPN expression in stroma may be part of a stromal response to aggressive tumour subtypes.

A combination of hemostatic agents may safely replace deep medullary suture during laparoscopic partial nephrectomy in a pig model.

PURPOSE: We assessed whether a combination of the fibrin tissue adhesive Tisseel® (human fibrinogen and thrombin) plus the hemostatic matrix FloSeal® (bovine derived gelatin matrix/human thrombin) could safely replace the conventional deep medullary suture without compromising outcomes. MATERIALS AND METHODS: Laparoscopic mid pole and one-third partial nephrectomy was performed on the right kidney of 12 female pigs. The only difference between the 2 groups of 6 pigs each was the use of a fibrin tissue adhesive plus hemostatic matrix combination in group 2 instead of the deep medullary running suture in control group 1. Renal scans and angiograms were performed at baseline and before sacrifice at 5-week followup. Retrograde in vivo pyelogram was also done. RESULTS: No significant difference was seen in operative parameters or postoperative course between the groups. Renal scans revealed a statistically insignificant trend toward greater uptake loss in group 1 and angiograms showed 3 major vessel occlusions in that group. No active bleeding was detected. Those 3 kidneys had significantly poorer postoperative uptake on renal scan than that of other kidneys (18.6% vs 39.4%, p = 0.013). Only 1 small asymptomatic pseudoaneurysm was noted in group 1. No urine leakage was found in either group. No major vessel occlusion, pseudoaneurysm or urinary complications developed in group 2. CONCLUSIONS: Even after deep one-third partial nephrectomy FloSeal with concurrent Tisseel appeared sufficient to control major medullary vascular injuries and replace the deep medullary conventional suture without compromising operative outcomes. The potential advantages seen during functional and vascular examinations by decreasing the risk of unnecessary segmental vessel occlusion need further clinical evaluation.

Long term evaluation of optimized Gleason grading in a large cohort of men with prostate cancer in Canada.

OBJECTIVES: To evaluate the International Society of Urological Pathology (ISUP) 5-tier grade grouping (GG) system of prostate cancers as well as previously proposed optimizations. PATIENTS AND METHODS: The PROCURE biobank is a prospective cohort study of patients with localized prostate cancer who underwent radical prostatectomy in Quebec province between 2005 and 2013. Surgical specimens were graded by experienced genitourinary pathologists using 2019 ISUP criteria. Follow-up was conducted until November 2021. The current 5-tier and a proposed 6-tier GG system were evaluated, the latter having two changes: 1) Gleason 3 + 4 and 4 + 3 tumors with minor/tertiary Gleason 5 patterns were upgraded to GG 3 and 4, respectively; and 2) patients in GG5 were separated based on primary Gleason pattern (4 or 5). Cox proportional hazards models and Harrell's concordance (C) indices were used for statistical analyses. RESULTS: 2003 patients were included (median follow-up: 8.7 years). The current 5-tier GG system predicted time to recurrence (hazard ratio [HR] 2.12, 95% confidence interval [95%CI] 1.99-2.25, C 0.717), androgen-deprivation therapy (HR 2.58, 95%CI 2.38-2.80, C 0.790), metastasis (HR 2.48, 95%CI 2.17-2.83, C 0.806), castration-resistant prostate cancer (HR 2.67, 95%CI 2.28-3.13, C 0.829), and cancer-specific mortality (HR 2.80, 95%CI 2.27-3.44, C 0.835). Goodness-of-fit further improved with the proposed 6-tier GG system, with Harrell's C of 0.733, 0.807, 0.827, 0.853, and 0.853, respectively. CONCLUSIONS: The 5-tier GG system predicted short- and long-term outcomes for patients with localized prostate cancer, and the proposed 6-tier GG system further improved its accuracy.

Endoscopic vascular targeted photodynamic therapy with the photosensitizer WST11 for benign prostatic hyperplasia in the preclinical dog model.

PURPOSE: Vascular targeted photodynamic therapy with WST11 (TOOKAD® Soluble) is in phase III clinical trials of an interstitial transperineal approach for focal therapy of prostate cancer. We investigated the safety and efficacy of the endourethral route in the context of benign prostatic hyperplasia in the dog model. MATERIALS AND METHODS: An optical laser fiber was positioned in the prostatic urethra of 34 dogs, including 4 controls. It was connected to a 753 nm diode laser at 200 mW/cm fluence, delivering 200 to 300 J. WST11 (5 to 15 mg/kg) was infused intravenously in 2 modes, including continuous, starting 5 to 15 minutes before and during illumination, or a bolus 5 to 10 minutes before illumination. Prostate ultrasound, cystourethrogram, urodynamics and histopathology were performed. Followup was 1 week to 1 year. RESULTS: Endourethral WST11 vascular targeted photodynamic therapy was uneventful in all except 1 dog, which experienced urinary retention but reached the 1-week end point. All prostates except those in controls showed hemorrhagic lesions. They consisted of 2 levels of concentric alterations, including periurethral necrosis with endothelial layer destruction and adjacent inflammation/atrophy with normal blood vessels. Prostatic urethral width increased as early as 6 weeks after treatment, while prostatic volume decreased, reaching 25% by 18 to 26 weeks. A parallel decrease in urethral pressure at 6 weeks lasted up to 1 year. CONCLUSIONS: We confirmed the vascular effect of endourethral WST11 vascular targeted photodynamic therapy. To our knowledge we report for the first time that the resulting periurethral necrosis led to significant, sustained widening of the prostatic urethra, accompanied by long-term improvement in urodynamic parameters. These findings support future clinical applications of this minimally invasive approach to benign prostatic hyperplasia.

Cell-by-cell quantification of the androgen receptor in benign and malignant prostate leads to a better understanding of changes linked to cancer initiation and progression.

The androgen receptor (AR) plays a crucial role in the development and homeostasis of the prostate and is a key therapeutic target in prostate cancer (PCa). The gold standard therapy for advanced PCa is androgen deprivation therapy (ADT), which targets androgen production and AR signaling. However, resistance to ADT develops via AR-dependent and AR-independent mechanisms. As reports on AR expression patterns in PCa have been conflicting, we performed cell-by-cell AR quantification by immunohistochemistry in the benign and malignant prostate to monitor changes with disease development, progression, and hormonal treatment. Prostates from radical prostatectomy (RP) cases, both hormone-naïve and hormone-treated, prostate tissues from patients on palliative ADT, and bone metastases were included. In the normal prostate, AR is expressed in >99% of luminal cells, 51% of basal cells, and 61% of fibroblasts. An increase in the percentage of AR negative (%AR-) cancer cells along with a gradual loss of fibroblastic AR were observed with increasing Gleason grade and hormonal treatment. This was accompanied by a parallel increase in staining intensity of AR positive (AR+) cells under ADT. Staining AR with N- and C-terminal antibodies yielded similar results. The combination of %AR- cancer cells, %AR- fibroblasts, and AR intensity score led to the definition of an AR index, which was predictive of biochemical recurrence in the RP cohort and further stratified patients of intermediate risk. Lastly, androgen receptor variant 7 (ARV7)+ cells and AR- cells expressing neuroendocrine and stem markers were interspersed among a majority of AR+ cells in ADT cases. Altogether, the comprehensive quantification of AR expression in the prostate reveals concomitant changes in tumor cell subtypes and fibroblasts, emphasizing the significance of AR- cells with disease progression and palliative ADT.

Refining the orthotopic dog prostate cancer (DPC)-1 model to better bridge the gap between rodents and men.

BACKGROUND: Rodent models are often suboptimal for translational research on human prostate cancer (PCa). To better fill the gap with human, we refined the previously described orthotopic dog prostate cancer (DPC)-1 model. METHODS: Cyclosporine (Cy) A was used for immune suppression at varying doses and time-periods prior and after orthotopic DPC-1 cell implantation in the dog prostate (n = 12). Follow up included digital rectal examination, ultrasound prostate imaging and biopsies of hypoechoic areas. At necropsy, the prostate, iliosacral lymph nodes (LN), lung nodules, and suspicious bone segments were collected for histopathology. RESULTS: 15 mg CyA/kg daily for 10 days was optimal for tumor take. Maintaining these conditions post-implantation resulted in a rapid tumor development within and beyond the prostate and in iliosacral LNs. To minimize tumor burden, 10 times less DPC-1 cells were implanted. A series of dogs was next followed for 3-4 months, under continuous immune suppression (n = 3) or with CyA interruption at 8.5 weeks (n = 2). In all instances, multifocal tumors were found within the prostate. Predominant patterns were micropapillary and cribriform. Metastases were present in iliosacral LNs and lungs. Moreover, pelvic bone metastases producing a mixed osteoblastic/osteolytic reaction were confirmed in two dogs, one per group. Lastly, the release of CyA 1-2 weeks post-implantation (n = 3) did not prevent tumor growth and spreading to LNs. CONCLUSIONS: The continuing growth of DPC-1 tumors despite the release of CyA and, for the first time, spreading to bones renders this refined model closer to the spontaneous canine and hormone-refractory phase of human PCa.

Peroxiredoxin 6 Peroxidase and Ca2+-Independent Phospholipase A2 Activities Are Essential to Support Male-Mouse Fertility.

Human infertility is an important health problem that affects one in six couples worldwide. Half of these cases are due to male infertility. Oxidative stress is a common culprit of male infertility, promoting lipid peroxidation and the oxidation of proteins and DNA in spermatozoa, thereby impairing motility, capacitation and fertilization. Peroxiredoxin 6 (PRDX6) possesses peroxidase and Ca2+-independent-phospholipase-A2 (iPLA2) activities that scavenge ROS and repair oxidized sperm membranes, respectively. PRDX6 protects spermatozoa against oxidative stress. Infertile men's spermatozoa have impaired motility, elevated lipid peroxidation levels and DNA damage due to low PRDX6 levels. A lack of PRDX6 is associated with male-mouse infertility. Here, we determined the impact of the absence of PRDX6 peroxidase or iPLA2 activities on male-mouse fertility. Two-month-old male C57Bl6/J (wild-type), Prdx6-/-, C47S and D140A knock-in (peroxidase- and iPLA2-deficient, respectively) male mice were challenged with an in vivo oxidative stress triggered by tert-butyl hydroperoxide (t-BHP). C47S and D140A males produced smaller litters compared to wild-type controls. The t-BHP treatment promoted a lower number of pups, high levels of lipid peroxidation, tyrosine nitration, and DNA oxidation in all mutant spermatozoa compared to wild-type controls. All mutant spermatozoa had impaired capacitation and motility. In summary, both PRDX6 peroxidase and iPLA2 activities are essential to support male-mouse fertility.

Fatty acid oxidation enzyme Δ3, Δ2-enoyl-CoA isomerase 1 (ECI1) drives aggressive tumor phenotype and predicts poor clinical outcome in prostate cancer patients.

Prostate cancer (PCa) metastases are highly enriched with genomic alterations including a gain at the 16p13.3 locus, recently shown to be associated with disease progression and poor clinical outcome. ECI1, residing at the 16p13.3 gain region, encodes Δ3, Δ2-Enoyl-CoA Delta Isomerase 1 (ECI1), a key mitochondrial fatty acid ß-oxidation enzyme. Although deregulated mitochondrial fatty acid ß-oxidation is known to drive PCa pathogenesis, the role of ECI1 in PCa is still unknown. We investigated the impacts of ECI1 on PCa phenotype in vitro and in vivo by modulating its expression in cell lines and assessed the clinical implications of its expression in human prostate tissue samples. In vitro, ECI1 overexpression increased PCa cell growth while ECI1 deficiency reduced its growth. ECI1 also enhanced colony formation, cell motility, and maximal mitochondrial respiratory capacity. In vivo, PCa cells stably overexpressing ECI1 injected orthotopically in nude mice formed larger prostate tumors with higher number of metastases. Immunohistochemistry analysis of the human tissue microarray representing 332 radical prostatectomy cases revealed a stronger ECI1 staining in prostate tumors compared to corresponding benign tissues. ECI1 expression varied amongst tumors and was higher in cases with 16p13.3 gain, high Gleason grade, and advanced tumor stage. ECI1 overexpression was a strong independent predictor of biochemical recurrence after adjusting for known clinicopathologic parameters (hazard ratio: 3.65, P < 0.001) or the established CAPRA-S score (hazard ratio: 3.95, P < 0.001). ECI1 overexpression was also associated with significant increased risk of distant metastasis and reduced overall survival. Overall, this study demonstrates the functional capacity of ECI1 in PCa progression and highlights the clinical implication of ECI1 as a potential target for the management of PCa.

Preclinical study of the novel vascular occluding agent, WST11, for photodynamic therapy of the canine prostate.

PURPOSE: Vascular targeted photodynamic therapy with WST09 shows promise for recurrent prostate cancer after radiation but hydrophobicity in aqueous solutions limited application. We tested the safety and efficacy of WST11, a novel water soluble vascular occluding agent, for vascular targeted photodynamic therapy of the dog prostate and compared it to WST09 vascular targeted photodynamic therapy. MATERIALS AND METHODS: Optical fibers were inserted in the prostate and connected to diode lasers. WST11 (Steba Biotech, Cedex, France) at varying doses, including a drug control with no light in 34 dogs, and WST09 (Steba Biotech) (2 mg/kg) in 3 dogs were infused during 10 minutes. Illumination was initiated at 5 or 10 minutes, and lasted up to 33.2 minutes based on laser fluence and delivered energy. Blood was collected for analysis and pharmacokinetics. The end point was at 1 week. RESULTS: No vascular targeted photodynamic therapy associated change was observed in blood pressure or blood test values. Circulating WST11 increased with drug infusion and decreased rapidly during 1 hour to reach undetectable levels by 24 hours. All except 1 dog with bowel intussusception did well after vascular targeted photodynamic therapy with only mild urinary symptoms that resolved within 24 to 48 hours. Lung and liver were normal. Hemorrhage was present in all prostates except controls. This translated into necrosis at a WST11 threshold and within a window of doses at fixed illumination. Necrosis was associated with loss of the vessel endothelial layer. Fluence highly impacted necrosis. WST11 vascular targeted photodynamic therapy was advantageously comparable to WST09 vascular targeted photodynamic therapy, and optimally ablated about 5.0 cm(3) of tissue per lobe and about 10 cm(3) of the whole prostate. CONCLUSIONS: The safety and efficacy of WST11 vascular targeted photodynamic therapy in the dog prostate support clinical applications for prostate cancer and benign prostatic hyperplasia.

The Fer tyrosine kinase cooperates with interleukin-6 to activate signal transducer and activator of transcription 3 and promote human prostate cancer cell growth.

Androgen withdrawal is the most effective form of systemic therapy for men with advanced prostate cancer. Unfortunately, androgen-independent progression is inevitable, and the development of hormone-refractory disease and death occurs within 2 to 3 years in most men. The understanding of molecular mechanisms promoting the growth of androgen-independent prostate cancer cells is essential for the rational design of agents to treat advanced disease. We previously reported that Fer tyrosine kinase level correlates with the development of prostate cancer and aggressiveness of prostate cancer cell lines. Moreover, knocking down Fer expression interferes with prostate cancer cell growth in vitro. However, the mechanism by which Fer mediates prostate cancer progression remains elusive. We present here that Fer and phospho-Y705 signal transducer and activator of transcription 3 (STAT3) are barely detectable in human benign prostate tissues but constitutively expressed in the cytoplasm and nucleus of the same subsets of tumor cells in human prostate cancer. The interaction between STAT3 and Fer was observed in all prostate cancer cell lines tested, and this interaction is mediated via the Fer Src homology 2 domain and modulated by interleukin-6 (IL-6). Moreover, IL-6 triggered a rapid formation of Fer/gp130 and Fer/STAT3 complexes in a time-dependent manner and consistent with changes in Fer and STAT3 phosphorylation and cytoplasmic/nuclear distribution. The modulation of Fer expression/activation resulted in inhibitory or stimulatory effects on STAT3 phosphorylation, nuclear translocation, and transcriptional activation. These effects translated in IL-6-mediated PC-3 cell growth. Taken together, these results support an important function of Fer in prostate cancer.

Antioxidant Enzymes and Male Fertility: Lessons from Knockout Models.

Significance: Spermatozoa are very sensitive to high levels of reactive oxygen species (ROS) due to the limited antioxidant systems present in these terminal cells. However, tight regulation of ROS levels must be ensured to accomplish the unique goal of the spermatozoon, that is, the transfer of the paternal genome into the mature oocyte during the fertilization process. Thus, it is essential that the restricted antioxidant enzymatic systems are active for sperm function. Recent Advances: Oxidative stress is associated with low sperm quality. High levels of ROS in spermatozoa produce oxidation of lipids, proteins, and DNA that lead to lipid peroxidation, oxidation of essential structural proteins and enzymes, and mutations due to oxidation of DNA. Critical Issues: In this study, we described the available knockout mouse models that helped to better understand the role of different antioxidant enzymes in male fertility. We focused mainly on those studies that directly explore the effects of the lack of these enzymes in male fertility and included information when existing knockout mouse models produced for other purposes were used. Special attention was given in this review to the consequences of the absence of antioxidant enzymes on sperm quality and fertility of aging males from the knockout models. Future Directions: Further studies using novel mouse models lacking different antioxidants and their combinations are essential to understand the consequences of high levels of ROS in aging testes, epididymes, spermatozoa, and embryo development to produce a healthy baby.

Long-Term Adverse Effects of Oxidative Stress on Rat Epididymis and Spermatozoa.

Oxidative stress is a common culprit of several conditions associated with male fertility. High levels of reactive oxygen species (ROS) promote impairment of sperm quality mainly by decreasing motility and increasing the levels of DNA oxidation. Oxidative stress is a common feature of environmental pollutants, chemotherapy and other chemicals, smoke, toxins, radiation, and diseases that can have negative effects on fertility. Peroxiredoxins (PRDXs) are antioxidant enzymes associated with the protection of mammalian spermatozoa against oxidative stress and the regulation of sperm viability and capacitation. In the present study, we aimed to determine the long-term effects of oxidative stress in the testis, epididymis and spermatozoa using the rat model. Adult male rats were treated with tert-butyl hydroperoxide (t-BHP) or saline (control group), and reproductive organs and spermatozoa were collected at 3, 6, and 9 weeks after the end of treatment. We determined sperm DNA oxidation and motility, and levels of lipid peroxidation and protein expression of antioxidant enzymes in epididymis and testis. We observed that cauda epididymal spermatozoa displayed low motility and high DNA oxidation levels at all times. Lipid peroxidation was higher in caput and cauda epididymis of treated rats at 3 and 6 weeks but was similar to control levels at 9 weeks. PRDX6 was upregulated in the epididymis due to t-BHP; PRDX1 and catalase, although not significant, followed similar trend of increase. Testis of treated rats did not show signs of oxidative stress nor upregulation of antioxidant enzymes. We concluded that t-BHP-dependent oxidative stress promoted long-term changes in the epididymis and maturing spermatozoa that result in the impairment of sperm quality.