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.

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.

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.

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.

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.

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.

Design and Development of a Fully Synthetic Multiplex Ligation-Dependent Probe Amplification-Based Probe Mix for Detection of Copy Number Alterations in Prostate Cancer Formalin-Fixed, Paraffin-Embedded Tissue Samples.

DNA copy number alterations (CNAs) are promising biomarkers to predict prostate cancer (PCa) outcome. However, fluorescence in situ hybridization (FISH) cannot assess complex CNA signatures because of low multiplexing capabilities. Multiplex ligation-dependent probe amplification (MLPA) can detect multiple CNAs in a single PCR assay, but PCa-specific probe mixes available commercially are lacking. Synthetic MLPA probes were designed to target 10 CNAs relevant to PCa: 5q15-21.1 (CHD1), 6q15 (MAP3K7), 8p21.2 (NKX3-1), 8q24.21 (MYC), 10q23.31 (PTEN), 12p13.1 (CDKN1B), 13q14.2 (RB1), 16p13.3 (PDPK1), 16q23.1 (GABARAPL2), and 17p13.1 (TP53), with 9 control probes. In cell lines, CNAs were detected when the cancer genome was as low as 30%. Compared with FISH in radical prostatectomy formalin-fixed, paraffin-embedded samples (n = 18: 15 cancers and 3 matched benign), the MLPA assay showed median sensitivity and specificity of 80% and 93%, respectively, across all CNAs assessed. In the validation set (n = 40: 20 tumors sampled in two areas), the respective sensitivity and specificity of MLPA compared advantageously with FISH and TaqMan droplet digital PCR (ddPCR) when assessing PTEN deletion (FISH: 85% and 100%; ddPCR: 100% and 83%) and PDPK1 gain (FISH: 100% and 92%; ddPCR: 93% and 100%). This new PCa probe mix accurately identifies CNAs by MLPA across multiple genes using low quality and quantities (50 ng) of DNA extracted from clinical formalin-fixed, paraffin-embedded samples.

A Novel Combination of γ-Tocopherol-Rich Mixture of Tocopherols and Ascorbic Acid Restores Fertility in Cases of Tyrosine Nitration-Associated Male Infertility in Mice.

Infertility is an important health problem that affects up to 16% of couples worldwide. Male infertility is responsible for 50% of the cases. Currently, a physical examination, hormone profiling and the evaluation of two consecutive semen samples (to determine the sperm concentration, motility, morphology and, in very few cases, sperm DNA integrity) are the sole tools that physicians have to evaluate infertility in men. Antioxidant therapy is often used to improve sperm quality and function in infertile men. However, there are controversial results regarding the efficacy of these treatments. Prdx6-/- male mice are subfertile, displaying significant oxidative damage in the lipids, proteins and DNA of their spermatozoa. Here, we used Prdx6-/- male mice to test whether a novel combination of tocopherols that contained 60% γ-tocopherol and ascorbic acid could restore their fertility. These mice were fed with the supplemented (Vit. Mix) or control diets. To assess sperm quality, we determined the motility, levels of lipid peroxidation, DNA oxidation and tyrosine nitration in the spermatozoa. The number of pups sired by the Prdx6-/- mice fed with the Vit. Mix diet was higher than that sired by the males fed with the control diet, and the pups' mortality was lower. The sperm quality was improved in the males fed with the supplemented diet. We concluded that treatment with a supplement composed of tocopherols and rich in γ-tocopherol and ascorbic acid is effective in restoring fertility in cases where oxidative stress and high levels of tyrosine nitration are associated with male infertility.

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.

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.

Snap29 mutant mice recapitulate neurological and ophthalmological abnormalities associated with 22q11 and CEDNIK syndrome.

Synaptosomal-associated protein 29 (SNAP29) encodes a member of the SNARE family of proteins implicated in numerous intracellular protein trafficking pathways. SNAP29 maps to the 22q11.2 region and is deleted in 90% of patients with 22q11.2 deletion syndrome (22q11.2DS). Moreover, bi-allelic SNAP29 mutations in patients are responsible for CEDNIK (cerebral dysgenesis, neuropathy, ichthyosis, and keratoderma) syndrome. A mouse model that recapitulates abnormalities found in these syndromes is essential for uncovering the cellular basis of these disorders. In this study, we report that mice with a loss of function mutation of Snap29 on a mixed CD1;FvB genetic background recapitulate skin abnormalities associated with CEDNIK, and also phenocopy neurological and ophthalmological abnormalities found in CEDNIK and a subset of 22q11.2DS patients. Our work also reveals an unanticipated requirement for Snap29 in male fertility and supports contribution of hemizygosity for SNAP29 to the phenotypic spectrum of abnormalities found in 22q11.2DS patients.

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.

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.

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.

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.

Genomic Gain of 16p13.3 in Prostate Cancer Predicts Poor Clinical Outcome after Surgical Intervention.

Identifying tumors with high metastatic potential is key to improving the clinical management of prostate cancer. Recently, we characterized a chromosome 16p13.3 gain frequently observed in prostate cancer metastases and now demonstrate the prognostic value of this genomic alteration in surgically treated prostate cancer. Dual-color FISH was used to detect 16p13.3 gain on a human tissue microarray representing 304 primary radical prostatectomy (RP) cases with clinical follow-up data. The results were validated in an external dataset. The 16p13.3 gain was detected in 42% (113/267) of the specimens scorable by FISH and was significantly associated with clinicopathologic features of aggressive prostate cancer, including high preoperative PSA (P = 0.03) levels, high Gleason score (GS, P < 0.0001), advanced pathologic tumor stage (P < 0.0001), and positive surgical margins (P = 0.009). The 16p13.3 gain predicted biochemical recurrence (BCR) in the overall cohort (log-rank P = 0.0005), and in subsets of patients with PSA ≤10 or GS ≤7 (log-rank P = 0.02 and P = 0.006, respectively). Moreover, combining the 16p13.3 gain status with standard prognostic markers improved BCR risk stratification and identified a subgroup of patients with high probability of recurrence. The 16p13.3 gain status was also associated with an increased risk of developing distant metastases (log-rank P = 0.03) further substantiating its role in prostate cancer progression.Implications: This study demonstrates the prognostic significance of the 16p13.3 genomic gain in primary prostate tumors, suggesting potential utility in the clinical management of the disease by identifying patients at high risk of recurrence who may benefit from adjuvant therapies. Mol Cancer Res; 16(1); 115-23. ©2017 AACR.

Deficiency of peroxiredoxin 6 or inhibition of its phospholipase A2 activity impair the in vitro sperm fertilizing competence in mice.

Prdx6 -/- male mice are subfertile, and the deficiency or inactivation of Peroxiredoxins (PRDXs) is associated with human male infertility. We elucidate the impact of the lack of PRDX6 or inhibition of its calcium-independent phospholipase A2 (Ca2+-iPLA2) activity by MJ33 on fertilization competence of mouse spermatozoa. Sperm motility, viability, fertilization and blastocyst rates were lower in Prdx6 -/- spermatozoa than in C57BL/6J wild-type (WT) controls (p ≤ 0.05). MJ33 inhibited the PRDX6 Ca2+-iPLA2 activity and reduced these parameters in WT spermatozoa compared with controls (p ≤ 0.05). Levels of lipid peroxidation and of superoxide anion (O2•─) were higher in Prdx6 -/- than in WT spermatozoa (p ≤ 0.05). MJ33 increased the levels of lipid peroxidation and mitochondrial O2•─ production in treated versus non-treated WT spermatozoa. Acrosome reaction, binding to zona pellucida and fusion with the oolemma were lower in Prdx6 -/- capacitated spermatozoa than WT capacitated controls and lower in WT spermatozoa treated with the PRDX6 inhibitor. In conclusion, the inhibition of the PRDX6 Ca2+-iPLA2 activity promotes an oxidative stress affecting viability, motility, and the ability of mouse spermatozoa to fertilize oocytes. Thus, PRDX6 has a critical role in the protection of the mouse spermatozoon against oxidative stress to assure fertilizing competence.

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.

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.